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| (1) Paropsis charybdis, the Eucalyptus tortoise beetle, is a serious defoliator of several Eucalyptus species in New Zealand. A series of laboratory experiments demonstrated the growth characteristics of larvae and adults when feeding on E. viminalis at 20°C. These were used as the data bases for quantifying its trophic relationships in terms of dry matter, energy and nitrogen. (2) The four larval stages lasted 4.0, 2.5, 3.0 and 9.5 days. Growth was exponential until the second day of the fourth instar, when the superficially inactive prepupal stage began. The pupal stage lasted 9.5 days. Female beetles started to lay eggs 15 days (av.) after eclosion. (3) Larvae attained a mean maximum dry weight (dwt) of 53.29 mg. Reproductive females weighed 63.40 mg, and males 46.71 mg. (4) The guts and their contents contributed up to 50% of total larval dry weight and 15% of adult dry weight. (5) Studies of the trophic relationships of P. charybdis larvae were based upon budgets whereby consumption (C) equals the sum of production (P), respiretion (R) and egesta (FU). Production was divided into gut-free larval production (P L ) and exuvia (P * )+R+FUin J: 3,561.5 = (491.3+43.4) + 284.5 +2,574.9 in mgN: 4.001 = (2.078 + 0.200) +1.657 (no R term) . P = P EX + P L * + P EX = C - FU - (P = P c + P c = C - FU - (P = P L reflects the change in body weight and P * + P EX + P AD reflects the change in body weight and P R + 0.252) + 0.285. The budget assumes that male P AD + P R ) + R +FU in mg dwt: 27.36 = (ΔP +2.25) +R + 14.53 in J: 591.1 = ΔP + 65.4) + 82.0 +362.6 in mgN: 0368 = (ΔP AD + 0.252) + 0.285. The budget assumes that male P R can be assumed to equal zero over a long term, although fluctuations were apparent during the experimental period. (7) The amount of leaf material removed but not eaten by larvae (NU) was 22.6 mg, 462.4 J or 0.526 mgN. Thus, the total material removed (MR = C +NU) was 194.3 mg, 3978.9 J or 4.527 mgN. NU per day for an average adult was 4.86 mg, 99.5 J or 0.113 mgN. Therefore adults removed 32.33 mg, 659.9 J or 0.751 mgN per day. (8) Ecological efficiencies (energy) of P. charybdis larvae (using P = P C + P M and A = assimilation + C - FU ) were: net ecological efficiency (P.A. AD )=56.8%, gross ecological efficiency (P.C L * )=26.8%, P.R. EX =121.5%. Adult efficiencies were: P. A. -1 =28.6%, P.C. -1 )=15.2%, assimilation efficiency (A.C. -1 =38.7% and P.R. -1 =55.7%. Efficiencies in terms of nitrogen were (larval data followed by adult data in parentheses): P.A. -1 =97.2 (71.4)%, P.C. -1 =11.1%, A.C. -1 =38.7% and P.R. -1 =55.7%. Efficiencies in terms of nitrogen were (larval data followed by adult data in parentheses): P.A. -1 =97.2 (71.4)%, P.C. -1 =56.9 (39.5)% and A.C. -1 =58.6 (55.3)%. (9) Regressions were calculated to link larval length (1) or larval live weight (lwt) and the dry weight of leaf material removed from a tree by that individual so that these results can be readily applied to field studies: logMR = -2.042 + 3.418 log1 logMR = -0.728 + 1.023 log 1wt.

Energy, Énergie, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Installations de production et de conversion d'énergie: énergie électrique, énergie thermique., Installations for energy generation and conversion: thermal and electrical energy., Centrales nucléaires à fission, Fission nuclear power plants, America, South America, Amérique du Sud, Amérique, America del sur, Analyse, Analysis, Arbre événement, Brésil, Brazil, Brasil, Centrale nucléaire, Nuclear power plant, Planta nuclear, Evaluation probabiliste, Programme ordinateur, Computer program, Risque, Risk, Riesgo, Sécurité, Safety, and Securidad

Description de la méthodologie utilisée dans le programme d'ordinateur d'analyse d'arbres d'événements pour des évaluations probabilistes de risques. Description détaillée de la structure du programme et de ses entrées et sorties. Discussion de quelques limitations de la version actuelle du programme.

Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Coreidae, Déprédateur, Pest, Plaga, Plante légumière, Vegetable crop, Planta leguminosa, Relation animal végétal, Animal plant relation, Relación animal vegetal, Rendement, Yield, Rendimiento, Seuil dégât économique, Economic injury level, Umbral daño económico, Seuil intervention, Treatment threshold, Umbral tratamiento, Surveillance population, Population survey, Vigilancia población, Vigna unguiculata, and Clavigralla tomenta sicollis

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte intégrée, Integrated pest control, Angiospermae, Arthropoda, Coreidae, Culture tropicale, Tropical crop, Cultivo tropical, Dicotyledones, Déprédateur, Pest, Plaga, Heteroptera, Insecta, Insecticide, Insecticida, Invertebrata, Leguminosae, Lepidoptera, Légumineuse grain, Grain legume, Leguminosa grano, Meliaceae, Plante pesticide, Pesticide crop, Planta plaguicida, Pyralidae, Spermatophyta, Azadirachta indica, Efficacité traitement, Treatment efficiency, Eficacia tratamiento, Extrait tissulaire, Tissue extract, Extracto tisular, Lutte antidéprédateur, Pest management, Manejo de plagas, Maruca testulalis, Origine végétale, Plant origin, Origen vegetal, Produit naturel, Natural product, Producto natural, Vigna unguiculata, Clavigralla tomentosicollis, Insecticide végétal, and Botanical insecticide

The insecticidal activity of neem, Azadirachta indica A. Juss., was tested on two major cowpea pests using different concentrations of aqueous extracts, and powders of both neem seed and kernel. The pests were larvae of Maruca testulalis Geyer (Lepidoptera: Pyralidae), the legume pod borer and Clavigralla tomentosicollis Stäl (Hemiptera: Coreidae), the cowpea coreid bug. Ife Brown, an improved local cowpea variety, and IT84S-2246, a breeding line from IITA grain legume programme, were used in the study. Neem proved effective in acting as an insecticide and affected the rates of development of both pests at concentration as low as ca. 9% solution (wt/vol.).

Medical oncology, Cancérologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Anticancéreux, Antineoplastic agents, Chimiothérapie, Chemotherapy, Anticancéreux, Antineoplastic agent, Anticanceroso, Chimiothérapie, Chemotherapy, Quimioterapia, Cycle cellulaire, Cell cycle, Ciclo celular, Cytométrie flux, Flow cytometry, Citometría flujo, Etude cas, Case study, Estudio caso, Exploration, Exploración, Glande mammaire, Mammary gland, Glándula mamaria, Homme, Human, Hombre, Phase S, S Phase, Fase S, Pronostic, Prognosis, Pronóstico, Préménopause, Premenopause, Premenopausia, Radiothérapie, Radiotherapy, Radioterapia, Traitement adjuvant, Adjuvant treatment, Tratamiento adyuvante, Traitement, Treatment, Tratamiento, Tumeur maligne, Malignant tumor, and Tumor maligno

Cancer chemotherapy interacts with cell proliferation, but data on the relationship between cancer cell replication and the effect of adjuvant chemotherapy are scarce. We have investigated the S-phase fractions of the primary tumour from premenopausal breast cancer patients who participated in a randomised trial comparing 12 cycles of polychemotherapy (CMF) with post-operative radiotherapy. DNA flow cytometry was performed on frozen tissues from 208 primary breast carcinomas, of which the S-phase fraction was estimated in 176 cases. There was a significantly higher benefit from CMF among patients with a high S-phase fraction (P=0.0033).

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Virology, Virologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pathologie infectieuse, Infectious diseases, Viroses, Viral diseases, Viroses expérimentales et modèles, Experimental viral diseases and models, Betaherpesvirinae, Cytokine, Citoquina, Herpesviridae, Infection, Infección, Mammalia, Rodentia, Vertebrata, Virus, Cytomegalovirus, Facteur nécrose tumorale α, Tumor necrosis factor α, Factor necrosis tumoral α, Histopathologie, Histopathology, Histopatología, Immunodépression, Immunosuppression, Inmunodepresión, Modèle animal, Animal model, Modelo animal, Multiplication virus, Virus multiplication, Multiplicación virus, Pathogénie, Pathogenesis, Patogenia, Pathologie expérimentale, Experimental disease, Patología experimental, Rat, Rata, Relation hôte virus, Host virus relation, Relación huesped virus, Spécificité tissu, Tissue specificity, Especificidad tejido, Symptomatologie, Symptomatology, Sintomatología, Virose, Viral disease, and Virosis

We investigated the role of tumor necrosis factor alpha (TNF-α) in the pathogenesis of rat cytomegalovirus (RCMV) infection. TNF-α levels found in the sera of radiation-immunosuppressed rats in the course of infection (>350 pg/ml) correlated with the development of RCMV disease. Administration of anti-TNF-α antibodies strongly reduced the severity of pneumonia and led to a reduction in virus titers. In immunocompetent rats, anti-TNF-α antibodies also significantly suppressed viral replication. Conversely, administration of TNF-α augmented RCMV replication and aggravated the disease signs. In vitro, TNF-α enhanced RCMV replication in the macrophage, whereas a reduction of viral replication was observed in fibroblasts, indicating that the effect on viral replication is cell type specific.

Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Microbiology, infectious diseases, Microbiologie, maladies infectieuses, Virology, Virologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Virologie, Virology, Cycle de développement, interférence, relations hôte-virus, pouvoir pathogène, souches diverses, Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains, Betaherpesvirinae, Cytokine, Citoquina, Herpesviridae, Infection, Infección, Mammalia, Rodentia, Vertebrata, Virus, Activité biologique, Biological activity, Actividad biológica, Cytomegalovirus, In vitro, In vivo, Interféron gamma, Gamma interferon, Interferón gamma, Modèle animal, Animal model, Modelo animal, Multiplication virus, Virus multiplication, Multiplicación virus, Pathologie expérimentale, Experimental disease, Patología experimental, Rat, Rata, Relation hôte virus, Host virus relation, Relación huesped virus, Virose, Viral disease, and Virosis

The role of gamma interferon (IFN-γ) in the resolution of rat cytomegalovirus (RCMV) infection was investigated. In the spleen, IFN-γ-producing cells reached maximum numbers on day 7 after infection. Prophylactic treatment with high doses of recombinant rat IFN-γ exerted antiviral activity in fibroblasts and protected immunosuppressed rats against a lethal RCMV challenge. Remarkably, in immunocompetent rats, neutralization of endogenous IFN-γ activity significantly reduced the numbers of RCMV antigen-expressing cells in the spleen, the predominant site of viral replication. Moreover, protection of radiation-immunosuppressed infected rats by transferred immune T cells was enhanced by coinjection of IFN-γ neutralizing antibodies.

Genetics, Génétique, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Otorhinolaryngologie. Stomatologie, Otorhinolaryngology. Stomatology, Face, maxillaires, dents, parodonte: maladies, sémiologie, Facial bones, jaws, teeth, parodontium: diseases, semeiology, Maladies non tumorales, Non tumoral diseases, Biologie moléculaire, Molecular biology, Biología molecular, Cavité buccale pathologie, Oral cavity disease, Cavidad bucal patología, Génétique, Genetics, Genética, Maladie congénitale, Congenital disease, Enfermedad congénita, Malformation, Malformación, Stomatologie, Stomatology, Estomatología, Déterminisme génétique, Genetic inheritance, Determinismo genético, Etude familiale, Family study, Estudio familiar, Fissure congénitale, Cleft, Fisura congenital, Homme, Human, Hombre, Linkage, Ligamiento, Lèvre, Lip, Labio, Palais, Palate, and Paladar

Nonsyndromic cleft lip with or without cleft palate (CL/P) is a common craniofacial developmental defect. Recent segregation analyses have suggested that major genes play a role in the etiology of CL/P. Linkage to 22 candidate genes was tested in 11 multigenerational families with CL/P, and 21 of these candidates were excluded. APOC2, 19q13.1, which is linked to the proto-oncogene BCL3, gave suggestive evidence for linkage to CL/P. The study was expanded to include a total of 39 multigenerational CLIP families. Linkage was tested in all families, using an anonymous marker, D19S178, and intragenic markers in BCL3 and APOC2. Linkage was tested under two models, autosomal dominant with reduced penetrance and affecteds only. Homogeneity testing on the two-point data gave evidence of heterogeneity at APOC2 under the affecteds-only model. Both models showed evidence of heterogeneity, with 43% of families linked at zero recombination to BCL3 when marker data from BCL3 and APOC2 were included. A maximum multipoint LOD score of 7.00 at BCL3 was found among the 17 families that had posterior probabilities ≥50% in favor of linkage. The transmission disequilibrium test provided additional evidence for linkage with the 3 allele of BCL3 more often transmitted to affected children. These results suggest that BCL3, or a nearby gene, plays a role in the etiology of CLIP in some families.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Plantes parasites. Mauvaises herbes, Parasitic plants. Weeds, Malherbologie, Weeds, Lutte biologique et autres méthodes de lutte, Biological control and other methods, Angiospermae, Arthropoda, Dicotyledones, Invertebrata, Spermatophyta, Verbenaceae, Animal auxiliaire, Beneficial animal, Animal benéfico, Efficacité, Efficiency, Eficacia, Insecta, Lutte biologique, Biological control, Lucha biológica, Mauvaise herbe, Weed, Malezas, Modèle, Models, Modelo, Phytophage, Phytophagous, Fitófago, Relation animal végétal, Animal plant relation, Relación animal vegetal, and Lantana camara

Dans un effort continu pour éradiquer ou au moins, réduire, la présence de Lantana camara L., adventice bien répandue à Guam, un suivi bi-mensuel a été effectué, sur une période de 4 ans et demi, pour étudier l'efficacité des ennemis naturels à affaiblir la plante et à diminuer le nombre de graines viables. Au total, huit agents de lutte biologique ont été recensés. Les insectes s'attaquant aux feuilles sont: Uroplata girardi Pic. (Col. : Chrysomelidae), Teleonemia scrupulosa Stäl (Hem. : Tingidae), Calycomyza lantanae Frick (Dip. : Agromyzidae) et Hypena strigata (F.) (Lep. : Noctuidae). Les papillons de nuit Lantanophaga pusillidactyla (Walker, (Lep. : Pterophoridae), Epinotia lantana (Busck) (Lep. : Tortricidae) et Adoxopheyes melia Clarke (Lep. : Tortricidae) s'attaquent aux fleurs ainsi que T. scrupulosa. E. lantana et Ophomyia lantanae (Froggatt) (Dip. : Agromyzidae) font des dégâts aux fruits. Un modèle empirique de lutte biologique a été établi à partir des données observées. Le modèle a mis en évidence que les 8 auxiliaires empêchent la production ou détruisent 225,9 baies par mètre carré sur une période d'observation de deux semaines. Sur cette même période, la production de fruits non abîmés observée au mètre carré n'est que de 96,1. Ainsi, les auxiliaires réduisent la production potentielle de fruits de 70,1 %. Le modèle a aussi permis d'estimer le rôle tenu par chaque auxiliaire dans la lutte biologique globale contre L. camara à Guam.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte intégrée, Integrated pest control, Angiospermae, Arthropoda, Bruchidae, Coleoptera, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Reduviidae, Spermatophyta, Callosobruchus maculatus, Canavalia ensiformis, Croissance, Growth, Crecimiento, Déprédateur, Pest, Plaga, Emergence, Emergencia, Insecticide, Insecticida, Larve, Larva, Légumineuse grain, Grain legume, Leguminosa grano, Mortalité, Mortality, Mortalidad, Mue, Molt, Muda, Origine végétale, Plant origin, Origen vegetal, Rhodnius prolixus, Toxicité, Toxicity, Toxicidad, Toxine, Toxin, and Toxina

Canatoxin is a toxic protein isolated from the jackbean, Cananvalia ensiformis. The toxin injected intraperitoneally is lethal for mice and rats; however, it is inactive if given orally. In this study, Manduca sexta (L.) (Lepidoptera), Schistocerca americana (Drury) (Orthoptera), Drosophila melanogaster (L.) (Diptera), Aedes aegypti (L.) (Diptera), Rhodnius prolixus (Stal) (Hemiptera), and Callosobruchus maculatus (F.) (Coleoptera) were fed on can-atoxin-containing diets. No effects were seen in M. sexta, S. americana, D. melanogaster, or A. aegypti. No traces of canatoxin were found in their feces, suggesting that the protein was digested completely by these insects, which characteristically have a trypsin-based digestion. In contrast, canatoxin was lethal for insects displaying cathepsin-based digestion. Thus, for C. maculatus, a diet containing 0.25% wt:wt canatoxin caused complete inhibition of larval growth. When R. prolixus were fed on canatoxin, 2 effects were seen: impairment of water excretion and increased lethality 48-96 h after feeding. The lethal effect of canatoxin in R. prolixus was blocked partially or completely when the digestion of the toxin by R. prolixus midgut enzymes was impaired. The data showed that canatoxin is highly toxic when ingested by some species of insects but not affecting others, probably in correlation with the characteristics of the digestive process of the insect.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Plant biology and physiology, Biologie et physiologie végétales, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie microbienne, Microbial ecology, Milieux divers (espace extraatmosphérique, air, eau), Various environments (extraatmospheric space, air, water), Bactérie, Bacteria, Cyanobacteria, Aphanizomenon flosaquae, Croissance, Growth, Crecimiento, Flottabilité, Buoyancy, Flotabilidad, Milieu marin, Marine environment, Medio marino, Photosynthèse, Photosynthesis, Fotosíntesis, Phytoplancton, Phytoplankton, Fitoplancton, Répartition verticale, Vertical distribution, Distribución vertical, and Vésicule gaz

Observations were made on the vertical distribution of colonies of Aphanizomenon flos-aquae for 9 d at a driftstation east of Bornholm Island in the Baltic Sea. The buoyant colonies were dispersed in the upper layers of the water column during periods of wind-induced mixing but floated up during calm periods. From measurements of the vertical light extinction, surface irradiance and the photosynthesis versus irradiance curve, calculations were made of the changes in the daily integral of photosynthesis with respect to time and depth throughout the water column. From these calculations it is demonstrated that net photosynthesis by the population of Aphanizomenon flos-aquae increased nearly threefold by floating up after a deep mixing event. It is estimated that, averaged over alternating periods of calm and mixing, the buoyancy provided by gas vesicles in this organism will result in a nearly twofold increase in photosynthesis. A quantitative analysis has been made of the relationship of the daily integral of photosynthesis by the Aphanizomenon population with the mean depth of the population in the water column and the daily insolation. The analysis shows that the integral decreases linearly with respect to mean depth.

Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Propriétés mécaniques. Rhéologie. Mécanique de la rupture. Tribologie, Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology, Frottement. Usure, Contact of materials. Friction. Wear, Choix matériau, Material selection, Selección material, Werkstoffwahl, Essai usure, Wear test, Prueba al desgaste, Verschleissversuch, Modélisation, Modeling, Modelización, Méthode étude, Investigation method, Método estudio, Untersuchungsmethode, Propriété mécanique, Mechanical properties, Propiedad mecánica, Revêtement dur, Hard coating, Revestimiento duro, Rugosité, Roughness, Rugosidad, Rauhigkeit, Traitement surface, Surface treatment, Tratamiento superficie, Oberflaechenbehandlung, Tribologie, Tribology, Tribología, Usure, Wear, Desgaste, Verschleiss, Vitesse usure, Wear rate, and Velocidad desgaste

The present paper describes how in depth analysis and modelling of wear data obtained from uni- and bidirectional wear tests were used to determine criteria for the selection of materials for tribological applications. Different wear modes in unidirectional ball on disc tests were linked to a load to roughness dependence between body and counterbody. The displacement of the ball is described using a particle flux model and the wear rate in bidirectional fretting tests is discussed, including a new concept based on dissipated frictional energy. The merits of the various approaches used to measure wear in tribological systems are also discussed.

Electronics, Electronique, Condensed state physics, Physique de l'état condensé, Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Electronique, Electronics, Electronique des semiconducteurs. Microélectronique. Optoélectronique. Dispositifs à l'état solide, Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices, Dispositifs optoélectroniques, Optoelectronic devices, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Domaines d'application, Application fields, Caractéristique temporelle, Time curve, Característica temporal, Caractéristique électrique, Electrical characteristic, Característica eléctrica, Diode électroluminescente, Light emitting diode, Diodo electroluminescente, Effet champ électrique, Electric field effect, Efecto campo eléctrico, Electroluminescence, Electroluminiscencia, Etude expérimentale, Experimental study, Estudio experimental, Mécanisme, Mechanism, Mecanismo, Phénylènevinylène polymère, Phenylenevinylene polymer, Fenilenovinileno polímero, Polymère conjugué, Conjugated polymer, Polímero conjugado, Vieillissement, Ageing, and Envejecimiento

Polymer light-emitting diodes (PLEDs) made with poly(p-phenylene vinylene) (PPV) using a non-ionic precursor route with indium-tin oxide (ITO) as anode and Al as cathode have been examined during continuous electrical stress in an oxygen-rich atmosphere. Three distinct regions in the time evolution of the equivalent electrical resistance and the light output of PLEDs are identified. Various electrical and analytical measurement results are presented to explain the main failure mechanisms. The most severe degradation mode can be identified as dielectric breakdown, resulting in 'hot spots' and ohmic leakage paths. The inhibition of the ohmic path formation by oxidation under ambient conditions results in a local delamination of the electrode, shrinking the active area of the device. This loss of active area caused by these oxidative burn-outs can clearly be observed by scanning electron microscopy ( SEM) and is consistent with secondary ion mass spectroscopy (SIMS) results. Emission microscopy (EMMI) inspection provides evidence for electric field induced ageing at defects present in the device. These defects are already present in the as-produced samples, e.g. particle impurities, interface roughness and structural weakness (edges of the Al electrodes).

Ecology, Ecologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Animaux, Animals, Protozoa. Invertebrata, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte biologique, Biological control, Arthropoda, Coleoptera, Heteroptera, Insecta, Invertebrata, Pentatomidae, Prédateur, Predator, Depredador, Tenebrionidae, Zone tropicale, Tropical zone, Zona tropical, Fréquence temporelle, Temporal frequency, Frecuencia temporal, Longévité, Longevity, Longevidad, Lutte biologique, Biological control, Lucha biológica, Nutrition, Nutrición, Relation prédateur proie, Predator prey relation, Relación depredador presa, Reproduction, Reproducción, Survie, Survival, Sobrevivencia, Tenebrio molitor, Oviposition, and Podisus rostratis

Reproduction and longevity of Podisus rostralis (Stål) (Heteroptera: Pentatomidae) females, fed at different intervals were studied in the Núcleo de Biotecnologia Aplicada à Agropecuária' (BIOAGRO), of the Universidade Federal de Viçosa (UFV), in Viçosa, Minas Gerais, Brazil, at 25 ± 2°C, 70 ± 10% R.H. and photophase of 12 hours. Females of P. rostralis were fed with Tenebrio molitor L. (Coleoptera: Tenebrionidae) larva, during 24 hours, every one, two, four, eight and 16 days. An inverse linear effect was found between oviposition period, egg batches/female, total number and number of eggs per day with feeding interval. Daily fed females laid more eggs (199.6) while those fed every 16 days showed lowest number of eggs (45.3). Longevity of P. rostralis was similar in all feeding intervals. Egg oviposition rate was reduced but females of this predator maintained its longevity which give then higher chances to maintain themselves in the ecosystem until occurs better conditions of preys.

Ecology, Ecologie, Oceanography, Océanographie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Microbiologie, Microbiology, Bactériologie, Bacteriology, Action d'agents physiques et chimiques sur les bactéries, Action of physical and chemical agents on bacteria, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie microbienne, Microbial ecology, Milieux divers (espace extraatmosphérique, air, eau), Various environments (extraatmospheric space, air, water), Bactérie, Bacteria, Milieu marin, Marine environment, Medio marino, Adaptation, Adaptación, Analyse quantitative, Quantitative analysis, Análisis cuantitativo, Bloom, Caroténoïde, Carotenoid, Carotenoide, Chlorophylle a, Chlorophyll a, Clorofila a, Cyanobacteria, Dynamique population, Population dynamics, Dinámica población, Emission oxygène, Oxygen emission, Emisión oxígeno, Facteur milieu, Environmental factor, Factor medio, Intensité lumineuse, Luminous intensity, Intensidad luminosa, Lumière, Light, Luz, Photosynthèse, Photosynthesis, Fotosíntesis, Pigment photosynthétique, Photosynthetic pigment, Pigmento fotosintético, Variation saisonnière, Seasonal variation, and Variación estacional

Animals, Antioxidants metabolism, Apoptosis drug effects, Body Weight drug effects, Carbon Tetrachloride antagonists inhibitors, Carcinogens toxicity, Cell Division drug effects, Diet, Diethylnitrosamine toxicity, Iron administration dosage, Iron metabolism, Kupffer Cells drug effects, Kupffer Cells pathology, Liver metabolism, Liver pathology, Liver Neoplasms, Experimental chemically induced, Liver Neoplasms, Experimental pathology, Male, Necrosis, Organ Size drug effects, Rats, Rats, Wistar, Ubiquinone metabolism, Vitamin E metabolism, Carbon Tetrachloride toxicity, Iron pharmacology, Liver drug effects, and Liver Neoplasms, Experimental prevention control

Background/aims: The aim of this study was to investigate if feeding with carbonyl iron would facilitate the development of preneoplastic lesions initiated by diethylnitrosamine (DEN) and promoted by CCl4-induced liver cirrhosis.
Methods: Male Wistar rats were fed a diet with 1.25%-2.5% carbonyl iron for 23 weeks and received intragastric injections of CCl4 (1.0 or 2.0 ml/kg per week) for 13 weeks, followed by one i.p. injection of DEN (200 mg/kg), after which CCl4 was administered for 8 additional weeks. Animals were killed 48 h after the first CCl4 injection to evaluate liver necrosis, 8 weeks later to evaluate fibrosis, and 9 weeks after DEN to determine formation of glutathione S-transferase 7,7 (GST-7,7) positive foci.
Results: Treatment with iron counteracted the increased serum alanine aminotransferase levels and liver necrosis following CCl4 administration. Hepatic levels of reduced Q9 and alpha-tocopherol were elevated in rats treated with CCl4 and decreased in rats treated with iron compared to the controls. Fibrogenesis was not altered by iron treatment. Nine weeks after DEN initiation, the number and volume density of GST-7,7-positive foci in rats treated with CCl4 were significantly increased as compared with controls, but co-treatment with iron inhibited this increase. Apoptotic index was increased in iron-loaded livers, and labelling index (the fraction of S-phase hepatocytes) was decreased by co-treatment with iron in livers exposed to CCl4.
Conclusion: Carbonyl iron depleted hepatic levels of antioxidants, it decreased CCl4-induced necrosis and cell proliferation, it enhanced apoptosis and did not facilitate fibrogenesis. These effects together may explain the suppression of CCl4-induced promotion after DEN initiation exerted by carbonyl iron in the present study.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Heteroptera, Insecta, Invertebrata, Leguminosae, Relation animal végétal, Animal plant relation, Relación animal vegetal, Spermatophyta, Age, Edad, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Coreidae, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Gousse, Pod, Vaina, Légumineuse grain, Grain legume, Leguminosa grano, Pentatomidae, Position, Posición, and Vigna unguiculata

Laboratory and screenhouse studies were carried out to assess the relationship between pod age and pod position of cowpea and damage by different pod bug species. The coreids Clavigralla tomentosicollis Stäl and Riptortus dentipes Fabricius caused significant damage to young pods of cultivated genotypes, in contrast to the coreid Anoplocnemis curvipes Fabricius and the pentatomid Aspavia armigera Fabricius which exhibited minor feeding activity. Percent seed damage declined with pod age, the critical stage for pod bug infestation being when pods were about eight days old. Clavigralla tomentosicollis and R. dentipes caused significantly higher damage to pods located within the leaf canopy, thus behaving differently from Anoplocnemis curvipes which showed a distinct preference for pods growing above the leaf canopy. The feeding activity of Aspavia armigera was not affected by the position of pods on the plant. Overall, the study suggests that cowpea genotypes with a short flowering period and pods held above the leaf canopy offer the most promise in the management of pod-sucking pests.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Sélection variétale. Amélioration spéciale, objectifs d'amélioration, Varietal selection. Specialized plant breeding, plant breeding aims, Résistance aux organismes nuisibles, Pest resistance, Déprédateurs, Pest animals, Amélioration génétique, Genetic improvement, Enriquecimiento genético, Angiospermae, Arthropoda, Coreidae, Culture tropicale, Tropical crop, Cultivo tropical, Dicotyledones, Déprédateur, Pest, Plaga, Fruit, Fruto, Heteroptera, Insecta, Invertebrata, Leguminosae, Légumineuse grain, Grain legume, Leguminosa grano, Plante sauvage, Wild plant, Planta salvaje, Spermatophyta, Comparaison interspécifique, Interspecific comparison, Comparación interespecífica, Cultivar, Dégât, Damage, Estrago, Effet dimensionnel, Size effect, Efecto dimensional, Etude en laboratoire, Laboratory study, Estudio en laboratorio, Gousse, Pod, Vaina, Graine, Seeds, Semillas, Infestation, Infestación, Lignée sélection, Breeding line, Línea selección, Mécanisme défense, Defense mechanism, Mecanismo defensa, Ressource génétique, Genetic resource, Recurso genético, Résistance insecte, Insect resistance, Resistencia insecto, Trichome, Tricoma, Vigna unguiculata, Clavigralla tomentosicollis, Péricarpe, Pericarp, and Vigna vexillata

Studies were conducted in the laboratory to investigate the different components of the resistance of Vigna vexillata A. Richards, TVnu 72, and several cultivars of cultivated Vigna spp. to infestation and damage by the brown cowpea coreid, Clavigralla tomentosicollis Stäl. The main objective was to determine the different roles of the pod wall and seeds, and the relationship between seed size, number, and damage by this insect. Results showed that both the pod wall and seed clearly contribute different components to the resistance of TVnu 72 to C. tomentosicollis. Analysis of the results suggests that the seed defences and the pod wall pericarp may be more important than are trichomes in this resistance. Seed number was found to influence the extent of damage in a more predictable manner than seed size. However, because both of these traits are generally inversely related and mutually exclusive, their individual effects cannot be completely separated. The implications of these traits in a breeding programme targeted at a specific consumer group are discussed.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Propriétés physiques non électroniques de couches minces, Physical properties of thin films, nonelectronic, Propriétés mécaniques et acoustiques, Mechanical and acoustical properties, Coefficient frottement, Friction factor, Dépôt physique phase vapeur, Physical vapor deposition, Essai usure, Wear testing, Etude expérimentale, Experimental study, Magnétron, Magnetrons, Microstructure, Molybdène sulfure, Molybdenum sulfides, Propriété mécanique, Mechanical properties, Propriété surface, Surface properties, Revêtement, Coatings, SEM, Tribologie, Tribology, Usure petit débattement, Fretting wear, Desgate pequinio desplazamiento, Usure, and Wear

MoSx coatings were prepared by bipolar pulse DC (balanced and unbalanced) magnetron-sputtering systems. Deposition parameters, cathode current density, argon pressure, bias voltage and magnetron sputtering conditions, were varied in order to obtain low friction and wear-resistant coatings. Composition and surface morphology were determined by energy dispersive X-rays and scanning electron microscopy, while the structure was investigated by X-ray diffraction. The friction and wear properties were investigated by fretting tests in ambient air of < 10% and 50% relative humidity. On proper selection of the argon pressure and the cathode current density, MoSx coatings characterised by a strong (002) basal plane orientation parallel to the substrate were obtained in a reproducible way. Such coatings deposited under optimised conditions exhibit very good lubricity and high wear-resistance, even in ambient air with a relative humidity of 50%. Conversely, when deposition parameters such as higher argon pressure and larger cathode current density result in the deposition of a MoSx coatings with a needle-like structure and preferential (100) and (110) plane orientations, a lower wear resistance is achieved especially in air of 50% relative humidity. Ion bombardment, achieved by applying a negative voltage bias or unbalanced sputtering conditions, improves the friction and wear performance. Conversely, a positive bias voltage deteriorates the tribological performance of the coatings. Experimental data on the friction and sliding wear resistance for MoSx coatings indicate that the best tribological properties are obtained with low sulfur and featureless MoSx coatings.

Marine biology, limnology, Biologie marine, limnologie, Ecology, Ecologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Autoécologie, Autoecology, Végétaux et champignons, Plants and fungi, Synécologie, Synecology, Ecosystèmes marins, Sea water ecosystems, Algae, Bacillariophyta, Facteur photique, Light effect, Factor fótico, Heterokontophyta, Milieu marin, Marine environment, Medio marino, Thallophyta, Eclairement énergétique, Irradiance, Aclaramiento energético, Extracellulaire, Extracellular, Extracelular, Photosynthèse, Photosynthesis, Fotosíntesis, Phytobenthos, Fitobentos, Polymère, Polymer, Polímero, Productivité biologique, Biological productivity, Productividad biológica, Cylindrotheca closterium, Extracellular polymeric substances, Microphytobenthos, and P/E curves

The partitioning of photosynthetically fixed carbon (C) into different fractions of intracellular and extracellular C pools by an axenic culture of Cylindrotheca closterium (Ehrenberg) and a field sample of natural benthic diatoms was studied using short-term incubation with 14C at different irradiances. Hence, excretion was directly dependent on the level of irradiance. During the incubations, a comparable amount of about 70 and 75% of the fixed C, respectively, was excreted by the culture and the field sample. This excreted C was distinguished in 2 operational fractions of attached (closely bound to the cells) and colloidal (soluble) material. In the field sample, the percentage of excreted C decreased at irradiances higher than 300 pmol photons m-2 s-1, but it was constant for the culture over the whole range of different irradiances applied. The percentage of extracellular polymeric substances (EPS) in the attached and colloidal material, as obtained by ethanol precipitation, was constant over the range of the provided irradiances for both samples. Subsamples of natural benthic diatoms were treated with an antibiotic cocktail in order to exclude bacterial activity which resulted in unexpected higher values of incorporated C in the fractions of total C, intracellular C, colloidal C and EPS.

General chemistry, physical chemistry, Chimie générale, chimie physique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Etat condense: structure, proprietes mecaniques et thermiques, Condensed matter: structure, mechanical and thermal properties, Surfaces et interfaces; couches minces et trichites (structure et propriétés non électroniques), Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties), Structure et morphologie de couches minces, Thin film structure and morphology, Structure et morphologie; épaisseur, Structure and morphology; thickness, Diffraction RX, XRD, Dépôt physique phase vapeur, Physical vapor deposition, Etude expérimentale, Experimental study, Frottement, Friction, Magnétron, Magnetrons, Microscopie électronique balayage, Scanning electron microscopy, Microstructure, Molybdène sulfure, Molybdenum sulfides, Propriété mécanique, Mechanical properties, Pulvérisation irradiation, Sputtering, Revêtement, Coatings, Tribologie, Tribology, Usure, and Wear

MoSx coatings were prepared with an unbalanced DC magnetron-sputtering system by varying the DC power mode, target type and liquid nitrogen trap. The composition and surface morphology were examined by energy dispersive X-ray and scanning electron microscopy; structural characterization was determined by X-ray diffraction. The friction and wear properties were evaluated with a fretting tester in dry (< 10% relative humidity) and humid (50% and 90% relative humidity) air. MoSx coatings deposited by simple DC power tended to form rougher surfaces, and had a higher edge orientation of crystallites with worse tribological performance than those by bipolar pulsed DC power. MoSx coatings made by a cold pressed target had a lower deposition rate, and were inclined to form (002) basal orientations parallel to the surface especially at higher argon pressures. The contents of oxygen and carbon in the MoSx coating with the use of liquid nitrogen trap were greatly reduced, but MoSx coatings had lower coefficients of friction and shorter wear life at higher relative humidity. The role of these deposition variables in the formation process is discussed.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Biochemistry, molecular biology, biophysics, Biochimie, biologie moléculaire, biophysique, Ecology, Ecologie, Geology, Géologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie microbienne, Microbial ecology, Milieux divers (espace extraatmosphérique, air, eau), Various environments (extraatmospheric space, air, water), Bactérie, Bacteria, Article synthèse, Review, Artículo síntesis, Cyanobacteria, Cycle biogéochimique, Biogeochemical cycle, Ciclo biogeoquímico, Diazotrophie, Diazotrophy, Diazotrofía, Fixation azote, Nitrogen fixation, Fijación nitrogeno, Milieu marin, Marine environment, Medio marino, Océan, Ocean, Océano, and Trichodesmium

The surface water of the marine environment has traditionally been viewed as a nitrogen (N) limited habitat, and this has guided the development of conceptual biogeochemical models focusing largely on the reservoir of nitrate as the critical source of N to sustain primary productivity. However, selected groups of Bacteria, including cyanobacteria, and Archaea can utilize dinitrogen (N2) as an alternative N source. In the marine environment, these microorganisms can have profound effects on net community production processes and can impact the coupling of C-N-P cycles as well as the net oceanic sequestration of atmospheric carbon dioxide. As one component of an integrated 'Nitrogen Transport and Transformations' project, we have begun to re-assess our understanding of (I) the biotic sources and rates of N2 fixation in the world's oceans, (2) the major controls on rates of oceanic N2 fixation, (3) the significance of this N2 fixation for the global carbon cycle and (4) the role of human activities in the alteration of oceanic N2 fixation. Preliminary results indicate that rates of N2 fixation, especially in subtropical and tropical open ocean habitats, have a major role in the global marine N budget. Iron (Fe) bioavailability appears to be an important control and is, therefore, critical in extrapolation to global rates of N2 fixation. Anthropogenic perturbations may alter N2 fixation in coastal environments through habitat destruction and eutrophication, and open ocean N2 fixation may be enhanced by warming and increased stratification of the upper water column. Global anthropogenic and climatic changes may also affect N2 fixation rates, for example by altering dust inputs (i.e. Fe) or by expansion of subtropical boundaries. Some recent estimates of global ocean N2 fixation are in the range of 100-200 Tg N (1-2 x 1014 g N) yr-1, but have large uncertainties. These estimates are nearly an order of magnitude greater than historical, pre-1980 estimates, but approach modern estimates of oceanic denitrification.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, and Fundamental and applied biological sciences. Psychology

The effects of secondary metabolites in different Vigna species on the development of Clavigralla tomentosicollis were investigated in an artificial seed system using different fractions of crude pod extracts, while the orientation response of this pod-bug to volatile extracts was studied using a dual-choice olfactometer. Feeding on the neutral fraction extracts, in contrast to the basic and acidic fractions, resulted in significantly higher mortalities, longer total developmental time, and lower growth index of the insects in comparison with controls. All volatile extracts elicited an avoidance reaction by C. tomentosicollis, except the volatile from the susceptible genotype IT84S-2246 which generally attracted as many insects as controls. Extracts from wild Vigna species showed higher activity than those from their cultivated relatives. The present study which has established that most secondary metabolites in cowpea pods were localized in the neutral fraction of the crude extract, could facilitate experiments on the separation and characterization of the toxic factors involved.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Condensed state physics, Physique de l'état condensé, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines interdisciplinaires: science des materiaux; rheologie, Cross-disciplinary physics: materials science; rheology, Science des matériaux, Materials science, Essais sur les matériaux, Materials testing, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Métrologie industrielle. Contrôle, Industrial metrology. Testing, Contrôle non destructif: méthodes et appareillages, Non-destructive testing: methods and equipments, Acier électrique, Electric furnace steel, Acero horno eléctrico, Conversion onde, Wave conversion, Conversión onda, Dispositif électromagnétique, Electromagnetic devices, Effet Barkhausen, Barkhausen effect, Effet champ magnétique, Magnetic field effects, En ligne, On line, En línea, Essai courant Foucault, Eddy current testing, Essai non destructif, Nondestructive testing, Essai perte magnétique, Magnetic leakage field testing, Control pérdida magnética, Fer, Iron, Grosseur grain, Grain size, Joint grain, Grain boundaries, Mesure électrique, Electrical measurement, Medida eléctrica, Métrologie, Metrology, Processus fabrication, Production process, Proceso fabricación, Procédé fabrication, Manufacturing processes, Visualisation, and Visualization

The results of investigation of the relation between the grain size in the intermediate stages of manufacturing electrical steel and various physical characteristics are given. The investigations are carried out for the purpose of clarifying the possibility of using these characteristics for arranging nondestructive testing of the grain size in the process of steel manufacturing. The paper contains the results of tests performed with the use of the methods of measuring the leakage magnetic fields on the grain boundaries by means of yttrium iron garnet films employed for visualization of the magnetic fields, the Barkhausen effect, the ultrasonic and eddy-current methods, the electromagnetic-acoustic conversion (EMAC) method, and the use of the relation between the grain size and the value of the coercive force.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Ecology, Ecologie, Entomology, Entomologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Signalements, symptômes, dégâts, importance économique, surveillance des populations, Records, symptoms, damages, economic importance, population surveys, Angiospermae, Arthropoda, Dicotyledones, Facteur milieu, Environmental factor, Factor medio, Heteroptera, Insecta, Invertebrata, Leguminosae, Spermatophyta, Coreidae, Défoliation, Defoliation, Defoliación, Dégât, Damage, Estrago, Déprédateur, Pest, Plaga, Feuille végétal, Plant leaf, Hoja vegetal, Gousse, Pod, Vaina, Infestation, Infestación, Structure, Estructura, Température, Temperature, Temperatura, Vigna unguiculata, Anoplocnemis curvipes, Clavigralla tomentosicollis, canopy temperature, defoliation, and pod position

Potted cowpea, Vigna unguiculata (L.) Walp., plants were used to determine the effects of defoliation and pod position relative to the leaf canopy on infestation and damage by the coreid pod-bugs Clavigralla tomentosicollis Stål and Anoplocnemis curvipes (F.). Temperature measurements were taken within and outside the canopy to determine whether there was a correlation to seed damage. Seed damage decreased significantly with increasing defoliation in plants infested with C. tomentosicollis; an inverse trend was observed with A. curvipes. Temperatures within the canopy increased as the number of leaves decreased. As observed in the defoliation experiment, C. tomentosicollis and A. curvipes reacted differently in a free-choice situation between pods located outside or within the canopy. Significantly higher numbers of C. tomentosicollis concealed themselves within the canopy, where they caused more severe damage to seeds, in comparison with numbers and damage outside the canopy. These trends were reversed for A. curvipes. There was a significant negative correlation between percentage of seed damage and temperature with C. tomentosicollis, and a significant positive correlation with A. curvipes, both in defoliated plants and those with pods distributed outside and within the canopy. Overall, plants with less dense canopy, and long peduncles holding pods outside the canopy showed some resistance to C. tomentosicollis, which is the most damaging pod bug on cowpea. Because such cowpea plants harbor fewer C. tomentosicollis, they are likely to suffer less overall damage from infestation by the complex of pod bugs that occur concurrently in cowpea fields.

Antibodies, Monoclonal immunology, Antibody Affinity immunology, Carrier Proteins genetics, Gene Expression, Humans, Immunoglobulin Variable Region immunology, Immunoglobulin Variable Region isolation purification, Immunoglobulin kappa-Chains genetics, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins immunology, Recombinant Fusion Proteins isolation purification, Substrate Specificity genetics, Substrate Specificity immunology, Antibodies, Monoclonal genetics, Antibody Affinity genetics, Gene Library, Immunoglobulin Variable Region genetics, Peptides immunology, and Plant Proteins immunology

The application of recombinant antibodies in plant biology research is limited because plant researchers have minimal access to high-quality phage display libraries. Therefore, we constructed a library of 1.3 x 10(10) clones displaying human single-chain variable fragments (scFvs) that is available to the academic community. The scFvs selected from the library against a diverse set of plant proteins showed moderate to high antigen-binding affinity together with high specificity. Moreover, to optimize an scFv as immunodetection agent, two expression systems that allow efficient production and purification of bivalent scFv-Fc and scFv-CkappaZIP fusion proteins were integrated. We are convinced that this antibody platform will further stimulate applications of recombinant antibodies such as the diagnostic detection or immunomodulation of specific antigens in plants.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Lutte chimique, Chemical control, Angiospermae, Arthropoda, Gramineae, Invertebrata, Monocotyledones, Pesticide, Pesticides, Plaguicida, Plante céréalière, Cereal crop, Planta cerealista, Spermatophyta, Zone tropicale, Tropical zone, Zona tropical, Date de plantation, Planting date, Fecha de plantación, Déprédateur, Pest, Plaga, Fertilisation azotée, Nitrogen fertilization, Fertilización nitrogenada, Infestation, Infestación, Insecta, Insecticide, Insecticida, Irrigation, Irrigación, Lutte antidéprédateur, Pest management, Manejo de plagas, Lutte chimique, Chemical control, Lucha química, Oryza sativa, Prise décision, Decision making, Toma decision, Rendement, Yield, Rendimiento, Résistance insecte, Insect resistance, Resistencia insecto, Seuil intervention, Action threshold, Umbral tratamiento, Pest control, colonisation pattern, decision making, insecticides, irrigated rice, nitrogen fertilisation, plant tolerance, planting date, and yield loss

Action thresholds as decision tools for insecticide application were developed and tested against the major insect pests of rice at four sites in the Philippines over a 13-year period. Action threshold treatments were compared to the farmers' practice, prophylactic insecticide usage, and an untreated check. Yield loss data using the insecticide check method partitioned yield losses over three crop growth stages in the same test fields. Chronic pests that exceeded action thresholds in 79% of fields were whorl maggot Hydrellia philippina Ferino (Diptera: Ephydridae), defoliators Naranga senescens Moore and Rivula atimeta (Swinhoe) (Lepidoptera: Noctuidae), leaffolders Cnaphalocrocis medinalis (Guenée) and Marasmia patnalis Bradley (Lepidoptera: Pyralidae), and stemborers Scirpophaga incertulas (Walker) and S. innotata (Walker) (Lepidoptera: Pyralidae). Minor chronic pests reached threshold levels in only one site each: rice bug Leptocorisa oratorius (F.) (Koronadal), whitebacked planthopper Sogatella furcifera (Horvath) (Zaragoza) and green leafhopper Nephotettix virescens (Distant) (Guimba); brown planthopper Nilaparvata lugens (Stål) did not exceed a threshold in any field. Stemborers were the most important pest group in terms of yield loss. Despite the insecticide check method underestimating losses, a mean crop loss of 0.62 t/ha was measured which showed ample scope for corrective action. But loss was evenly distributed across crop growth stages (0.15 0.24 t/ha) reducing the impact of insecticides. Action threshold treatments overall outyielded the untreated check, more so in the two sites with highest pest density. The benefit of thresholds was to reduce insecticide usage, as a cost saving. However all the practices showed poor economic returns including the farmers' practice. Farmers' practice employed low insecticide dosages and timing was not consistent with pest damage, but yields were often similar to threshold treatments. Farmers appear to use insecticide more for risk aversion than for profit. The best threshold characters when evaluated against resulting pest density and yield loss criteria showed accuracies > 90% correct decisions. Future work is needed to improve the insecticide response rather than monitoring tools. Thresholds need to be incorporated into improved crop management, which was often found suboptimal by farmers, to take advantage of the high levels of tolerance in modern high tillering cultivars. Crop husbandry practices which improve yield potential such as selection of longer maturing varieties and nitrogen fertilizer may be a more effective pest management strategy than insecticides.

Medical oncology, Cancérologie, Medical laboratory techniques, Techniques de laboratoire médical, General medicine general surgery, Médecine et chirurgie générales, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Gynecologie. Andrologie. Obstetrique, Gynecology. Andrology. Obstetrics, Pathologie de la glande mammaire, Mammary gland diseases, Tumeurs, Tumors, Techniques d'exploration et de diagnostic (generalites), Investigative techniques, diagnostic techniques (general aspects), Anatomopathologie. Exploration cytologique. Biochimie. Spectrométries. Méthodes cliniques et paracliniques diverses, Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques, Glande mammaire pathologie, Mammary gland diseases, Glándula mamaria patología, Tumeur maligne, Malignant tumor, Tumor maligno, Adjuvant, Coadyuvante, Anatomopathologie, Anatomic pathology, Anatomía patológica, Essai clinique, Clinical trial, Ensayo clínico, Paramètre, Parameter, Parámetro, Préménopause, Premenopause, Premenopausia, Tamoxifène, Tamoxifene, Tamoxifeno, Cancer sein, Breast cancer, and Cáncer pecho

Background: Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivity, are still poorly defined. Breast cancer can be subdivided according to standard pathological parameters including histological type, grade, and assessment of proliferation. These parameters are the net result of combinations of genetic alterations effecting tumour behaviour and could potentially reflect subtypes that respond differently to endocrine treatment. Aims: To investigate the usefulness of these parameters as predictors of the response to tamoxifen in premenopausal women with breast cancer. Materials/methods: Clinically established pathological parameters were assessed and related to the tamoxifen response in 500 available tumour specimens from 564 premenopausal patients with breast cancer randomised to either two years of tamoxifen or no treatment with 14 years of follow up. Proliferation was further evaluated by immunohistochemical Ki-67 expression. Results: Oestrogen receptor positive ductal carcinomas responded as expected to tamoxifen, whereas the difference in recurrence free survival between control and tamoxifen treated patients was less apparent in the relatively few lobular carcinomas. For histological grade, there was no obvious difference in treatment response between the groups. The relation between proliferation and tamoxifen response seemed to be more complex, with a clear response in tumours with high and low proliferation, whereas tumours with intermediate proliferation defined by Ki-67 responded more poorly. Conclusions: Clinically established pathology parameters seem to mirror the endocrine treatment response and could potentially be valuable in future treatment decisions for patients with breast cancer.

Animals, Brazil, Hemiptera metabolism, Pheromones biosynthesis, and Pheromones chemistry

In recent years the growing concern about environmental changes and how we are using the natural resources have triggered a search for natural products as alternatives to synthetic pesticides. The stink bugs produce a wide variety of chemical compounds (semiochemicals) that show potential to manage these insects. The stink bugs Chinavia impicticornis (Stål), C. ubica (Rolston), Dichelops melacanthus (Dallas), Euschistus heros (F.), Piezodorus guildinii (Westwood), Thyanta perditor (Westwood) and Tibraca limbativentris (Stål) had their blends of defensive compounds evaluated both qualitative and quantitatively. The main compounds identified on the glands of Brazilian stink bugs are: 2-alkenals, mainly the E isomer; saturated aliphatic hydrocarbons; and 4 oxo-(E)-2-alkenals. The first sex attractant determined from a stink bug was obtained from Nezara viridula L., and consists on a mix of two isomers cis - and trans bisabolene-epoxides. Later the soybean stink bug E. heros was also studied and its sex attractant was identified as three esters methyl: 2,6,10-trimethyldecanoate, methyl 2,6,10-trimethyldodecanoate, and methyl E2, Z4-decadienoate. Recently, three new Brazilian sting bugs were studied and had their sex attractant elucidated. Males of T. perditor produce the ester, methyl 2E,4Z,6Z-decatrienoate. Whereas, the stink bug, P. guildinii has as sexual pheromone, the sesquiterpene beta-sesquiphellandrene, and the stink bug T. limbativentris produces as sex attractant the zingiberenol. In this review we discuss the advances obtained on the behaviour and identification of sex and defensive compound of stink bugs from Brazilian crops and the application of this knowledge to manage the stink bugs.

Breast Neoplasms pathology, Breast Neoplasms radiotherapy, Chemotherapy, Adjuvant, Combined Modality Therapy, Female, Follow-Up Studies, Gene Frequency, Humans, Immunohistochemistry, Neoplasm Recurrence, Local epidemiology, Prognosis, Randomized Controlled Trials as Topic, Retinoblastoma Protein genetics, Time Factors, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Breast Neoplasms drug therapy, Breast Neoplasms genetics, Cyclin E genetics, and Gene Expression Regulation, Neoplastic

Cyclin E and the retinoblastoma protein (Rb) are both important regulators of the G1 phase in the cell cycle. Overexpression of cyclin E and lost expression of Rb has previously been observed in breast tumours at frequencies of 10-50% and 20-30%, respectively. We explored the prognostic role of cyclin E and Rb in breast cancer patients randomised for tamoxifen (TAM), CMF (cyclophosphamide, metotrexate, 5-fluorouracil) chemotherapy and radiotherapy (RT) and how their expression affects the patients' response to treatment. Protein expression was assessed with immunohistochemistry. We found overexpression of cyclin E in 32.1% (71/221) of the tumours and loss of Rb expression in 25.0% (59/236). Increased expression of cyclin E correlated to dysfunctional p53 (P=0.003) while loss of Rb correlated to normal p53 status (P=0.001). Our results suggest that patients with high cyclin E tumours have less benefit from tamoxifen (ER+, TAM vs. no TAM; RR=0.97; 95% CI, 0.36-2.60) than patients whose tumours show low expression (ER+, TAM vs. no TAM; RR =0.41; 95% CI, 0.24-0.72). Cyclin E also tended to predict the benefit from radiotherapy with a local recurrence rate of 0.31 (RT vs. CMF; 95% CI, 0.12-0.83) for patients with low expression and 0.68 (RT vs. CMF; 95% CI, 0.2-2.32) for patients with high expression of cyclin E. When the p53 status was taken in consideration the results showed that patients with both normal p53 and normal Rb expression had considerably lower locoregional recurrence rate when treated with radiotherapy instead of CMF (RR=0.17; 95% CI, 0.052-0.58) as compared to patients with either altered Rb or p53 or both (RR=0.70; 95% CI, 0.28-1.73).

The marine filamentous nonheterocystous nitrogen-fixing cyanobacterium Lyngbya aestuarii (F. K. Mert.) Liebman ex Gomont CCY 9616 was grown under diazotrophic and nondiazotrophic conditions and under an alternating 16:8 light:dark (L:D) regime. Nitrogenase activity appeared just before the onset of the dark period, reaching its maximum 1-2 h in the dark, subsequently decreasing to zero at the beginning of the following light period. Nitrogenase activity was only detected at low levels of O2 (5%) and when the culture was grown in the absence of combined nitrogen. Quantitative reverse transcriptase-PCR (RT-PCR) analysis of one of the structural genes encoding nitrogenase, nifK, showed that the highest levels of transcription preceded the maximum activity of nitrogenase by 2-4 h. nifK transcription was not completely abolished during the remaining time of the 24 h cycle. Even in the presence of nitrate, when nitrogenase activity was undetectable, nifK was still transcribed. The H2 -uptake activity seemed to follow the nitrogenase, but the transcription of hupL (gene encoding the large subunit of uptake hydrogenase) preceded the nifK transcription. However, H2 -uptake and hupL transcription occurred throughout the 24 h cycle as well as under nondiazotrophic conditions, albeit at much lower levels. The hoxH transcript levels (a structural gene coding for the bidirectional hydrogenase) were similar under diazotrophic or nondiazotrophic conditions but slightly higher during the dark period. All three enzymes investigated are involved in H2 metabolism. It is concluded that the uptake hydrogenase is mainly responsible for H2 uptake. Nevertheless, uptake hydrogenase and nitrogenase do not seem to be coregulated.
(© 2009 Phycological Society of America.)

Adult, Alternative Splicing genetics, Amino Acid Sequence, Animals, Cell Line, Cyclic AMP metabolism, Cyclic AMP-Dependent Protein Kinases metabolism, Family, Female, Gene Expression Regulation, Neoplastic, Humans, Intracellular Signaling Peptides and Proteins chemistry, Intracellular Signaling Peptides and Proteins metabolism, Male, Middle Aged, Molecular Sequence Data, Mutant Proteins genetics, Mutant Proteins metabolism, Mutation, Missense genetics, Pedigree, Pituitary Neoplasms enzymology, Promoter Regions, Genetic genetics, RNA Splice Sites genetics, RNA, Messenger genetics, RNA, Messenger metabolism, Rats, Signal Transduction, Intracellular Signaling Peptides and Proteins genetics, Mutation genetics, and Pituitary Neoplasms genetics

Familial isolated pituitary adenoma (FIPA) is an autosomal dominant condition with variable genetic background and incomplete penetrance. Germline mutations of the aryl hydrocarbon receptor interacting protein (AIP) gene have been reported in 15-40% of FIPA patients. Limited data are available on the functional consequences of the mutations or regarding the regulation of the AIP gene. We describe a large cohort of FIPA families and characterize missense and silent mutations using minigene constructs, luciferase and beta-galactosidase assays, as well as in silico predictions. Patients with AIP mutations had a lower mean age at diagnosis (23.6+/-11.2 years) than AIP mutation-negative patients (40.4+/-14.5 years). A promoter mutation showed reduced in vitro activity corresponding to lower mRNA expression in patient samples. Stimulation of the protein kinase A-pathway positively regulates the AIP promoter. Silent mutations led to abnormal splicing resulting in truncated protein or reduced AIP expression. A two-hybrid assay of protein-protein interaction of all missense variants showed variable disruption of AIP-phosphodiesterase-4A5 binding. In summary, exonic, promoter, splice-site, and large deletion mutations in AIP are implicated in 31% of families in our FIPA cohort. Functional characterization of AIP changes is important to identify the functional impact of gene sequence variants.

Computational Biology, Cyclin-Dependent Kinases metabolism, Cyclins metabolism, DNA Replication, Luciferases metabolism, Mitosis, Models, Biological, Multiprotein Complexes metabolism, Protein Binding, Protein Interaction Mapping, Reproducibility of Results, Arabidopsis cytology, Arabidopsis metabolism, Arabidopsis Proteins metabolism, Cell Cycle, and Cell Cycle Proteins metabolism

Cell proliferation is the main driving force for plant growth. Although genome sequence analysis revealed a high number of cell cycle genes in plants, little is known about the molecular complexes steering cell division. In a targeted proteomics approach, we mapped the core complex machinery at the heart of the Arabidopsis thaliana cell cycle control. Besides a central regulatory network of core complexes, we distinguished a peripheral network that links the core machinery to up- and downstream pathways. Over 100 new candidate cell cycle proteins were predicted and an in-depth biological interpretation demonstrated the hypothesis-generating power of the interaction data. The data set provided a comprehensive view on heterodimeric cyclin-dependent kinase (CDK)-cyclin complexes in plants. For the first time, inhibitory proteins of plant-specific B-type CDKs were discovered and the anaphase-promoting complex was characterized and extended. Important conclusions were that mitotic A- and B-type cyclins form complexes with the plant-specific B-type CDKs and not with CDKA;1, and that D-type cyclins and S-phase-specific A-type cyclins seem to be associated exclusively with CDKA;1. Furthermore, we could show that plants have evolved a combinatorial toolkit consisting of at least 92 different CDK-cyclin complex variants, which strongly underscores the functional diversification among the large family of cyclins and reflects the pivotal role of cell cycle regulation in the developmental plasticity of plants.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Généralités, Generalities, Vecteurs d'importance medicale, nuisances, depredateurs des denrees et materiaux: surveillance des populations et lutte, Medically important nuisances and vectors, pests of stored products and materials: population survey and control, Vecteurs. Hôtes intermédaires, Vectors. Intermediate hosts, Arthropoda, Bactérie, Bacteria, Cicadomorpha, Homoptera, Insecta, Invertebrata, Mollicutes, Mycoplasmatales, Spiroplasmataceae, Cicadellidae, Dalbulus maidis, Etude expérimentale, Experimental study, Estudio experimental, Maïs, Corn, Maiz, Spiroplasma kunkelii, Vecteur, Vector, corn leafhopper, corn stunt, and spiroplasmas

Corn stunt caused by the mollicute Spiroplasma kunkelii (Whitcomb) is potentially one of the most severe diseases affecting the corn (Zea mays L.) crop in the Americas, and the leafhopper Dalbulus maidis (DeLong & Wolcott) is considered its most important vector. However, other insects seen quite frequently in corn crops might well be its vectors in Argentina. To identify any leafhoppers species other than D. maidis that can transmit S. kunkelii, transmission assays were conducted, using individuals of Exitianus obscurinervis (Stål) collected in field and reared under controlled conditions. S. kunkelii was transmitted to corn plants by E. obscurinervis. The pathogen was transmitted to seven of the 11 plants, which showed characteristic corn stunt symptoms, and the presence of the pathogen was confirmed by DAS-ELISA. The presence of S. kunkelii in the E. obscurinervis individuals used in transmission experiments was confirmed by polymerase chain reaction and electron microscopy. The current study shows the existence of a new experimental vector of S. kunkelii, the leafhopper E. obscurineruis, which acquired spiroplasmas from infected plants and inoculated it to healthy plants.

Animals, Bacterial Typing Techniques, Carrier State microbiology, Cluster Analysis, Escherichia coli isolation purification, Genotype, Humans, Molecular Epidemiology, Molecular Typing, Multilocus Sequence Typing, Netherlands, Plasmids analysis, Polymerase Chain Reaction, Zoonoses microbiology, Carrier State veterinary, Escherichia coli enzymology, Escherichia coli genetics, Escherichia coli Infections microbiology, Meat microbiology, Poultry microbiology, and beta-Lactamases genetics

Intestinal carriage of extended-spectrum beta-lactamase (ESBL) -producing bacteria in food-producing animals and contamination of retail meat may contribute to increased incidences of infections with ESBL-producing bacteria in humans. Therefore, distribution of ESBL genes, plasmids and strain genotypes in Escherichia coli obtained from poultry and retail chicken meat in the Netherlands was determined and defined as 'poultry-associated' (PA). Subsequently, the proportion of E. coli isolates with PA ESBL genes, plasmids and strains was quantified in a representative sample of clinical isolates. The E. coli were derived from 98 retail chicken meat samples, a prevalence survey among poultry, and 516 human clinical samples from 31 laboratories collected during a 3-month period in 2009. Isolates were analysed using an ESBL-specific microarray, sequencing of ESBL genes, PCR-based replicon typing of plasmids, plasmid multi-locus sequence typing (pMLST) and strain genotyping (MLST). Six ESBL genes were defined as PA (bla(CTX-M-1) , bla(CTX-M-2) , bla(SHV-2) , bla(SHV-12) , bla(TEM-20) , bla(TEM-52) ): 35% of the human isolates contained PA ESBL genes and 19% contained PA ESBL genes located on IncI1 plasmids that were genetically indistinguishable from those obtained from poultry (meat). Of these ESBL genes, 86% were bla(CTX-M-1) and bla(TEM-52) genes, which were also the predominant genes in poultry (78%) and retail chicken meat (75%). Of the retail meat samples, 94% contained ESBL-producing isolates of which 39% belonged to E. coli genotypes also present in human samples. These findings are suggestive for transmission of ESBL genes, plasmids and E. coli isolates from poultry to humans, most likely through the food chain.
(2011 The Authors. Clinical Microbiology and Infection; 2011 European Society of Clinical Microbiology and Infectious Diseases.)

Animals, Brazil, Circadian Rhythm, Climate, Demography, Ecosystem, Genetic Variation, Species Specificity, Temperature, Arecaceae genetics, Arecaceae parasitology, and Rhodnius genetics

This work evaluated the occurrence and genetic structure of Rhodnius nasutus sampled in two sites using morphometry and microsatellites. These sites, presented distinct abiotic features and palm trees: (i) nine Attalea speciosa palm trees, so called babaçu, were sampled from the Meruoca Mountain Ridge, a sloping region of reminiscent forest in the state of Ceará, Brazil, and (ii) 17 Copernicia prunifera palm trees, so called carnaúba, were sampled in the scrub savanna region (Sobral district) that surrounds the mountain ridge. Of the twenty-six palm trees dissected, 70.6% of carnauba and 88.9% of babaçu were infested by R. nasutus. The micro-climatic data where R. nasutus were sheltered demonstrated that the babaçu and carnaúba palm trees presented significant differences (p < 0.05) in relation to the external environment, except for temperature and relative humidity regulation, suggesting that the architecture of the babaçu crown keeps a more stable micro-environment. The morphometric studies of the F1 generation demonstrated that insects from the babaçu (A. speciosa) were significantly larger (p = 0.000) than those collected in carnaúba (C. prunifera) palm trees. Also, microsatellite analysis demonstrated a high genetic differentiation between the two groups of R. nasutus (R(st) = -0.77). Our results suggest that the difference in size between the populations is probably related to an incipient process of genetic drift in populations associated to each palm tree, probably also driven by the different climatic features observed in these micro-environments.
(Copyright © 2011 Elsevier B.V. All rights reserved.)

Adolescent, Adult, Aged, Bacterial Proteins genetics, Bacterial Typing Techniques, Child, Child, Preschool, Enterobacteriaceae classification, Humans, Infant, Infant, Newborn, Microbial Sensitivity Tests, Middle Aged, Netherlands, Young Adult, Anti-Bacterial Agents pharmacology, Cephalosporin Resistance genetics, Cephalosporins pharmacology, Enterobacteriaceae drug effects, Enterobacteriaceae genetics, and beta-Lactamases genetics

There is a global increase in infections caused by Enterobacteriaceae with plasmid-borne β-lactamases that confer resistance to third-generation cephalosporins. The epidemiology of these bacteria is not well understood, and was, therefore, investigated in a selection of 636 clinical Enterobacteriaceae with a minimal inhibitory concentration >1 mg/L for ceftazidime/ceftriaxone from a national survey (75% E. coli, 11% E. cloacae, 11% K. pneumoniae, 2% K. oxytoca, 2% P. mirabilis). Isolates were investigated for extended-spectrum β-lactamases (ESBLs) and ampC genes using microarray, PCR, gene sequencing and molecular straintyping (Diversilab and multi-locus sequence typing (MLST)). ESBL genes were demonstrated in 512 isolates (81%); of which 446 (87%) belonged to the CTX-M family. Among 314 randomly selected and sequenced isolates, bla(CTX-M-15) was most prevalent (n = 124, 39%), followed by bla(CTX-M-1) (n = 47, 15%), bla(CTX-M-14) (n = 15, 5%), bla(SHV-12) (n = 24, 8%) and bla(TEM-52) (n = 13, 4%). Among 181 isolates with MIC ≥16 mg/L for cefoxitin plasmid encoded AmpCs were detected in 32 and 27 were of the CMY-2 group. Among 102 E. coli isolates with MIC ≥16 mg/L for cefoxitin ampC promoter mutations were identified in 29 (28%). Based on Diversilab genotyping of 608 isolates (similarity cut-off >98%) discriminatory indices of bacteria with ESBL and/or ampC genes were 0.994, 0.985 and 0.994 for E. coli, K. pneumoniae and E. cloacae, respectively. Based on similarity cut-off >95% two large clusters of E. coli were apparent (of 43 and 30 isolates) and 21 of 21 that were typed by belonged to ST131 of which 13 contained bla(CTX-M-15). Our findings demonstrate that bla(CTX-M-15) is the most prevalent ESBL and we report a larger than previously reported prevalence of ampC genes among Enterobacteriaceae responsible for resistance to third-generation cephalosporins.

Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Entomology, Entomologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Invertebres, Invertebrates, Insecta, Phytopathologie. Zoologie agricole. Protection des cultures et des forets, Phytopathology. Animal pests. Plant and forest protection, Protozoaires. Invertébrés, Protozoa. Invertebrates, Lutte, Control, Généralités, Generalities, Agrume, Citrus fruit, Agrios, Angiospermae, Arthropoda, Bactérie, Bacteria, Cicadomorpha, Dicotyledones, Homoptera, Insecta, Invertebrata, Mollicutes, Rutaceae, Spermatophyta, Bocage, Grove, Boscaje, Cicadellidae, Citrus, Hôte, Host, Huesped, Maladie, Disease, Enfermedad, Mauvaise herbe, Weed, Malezas, Phloème, Phloem, Liber, Phytoplasme, Phytoplasma, Fitoplasma, Prévalence, Prevalence, Prevalencia, Sève, Sap, Savia, Vecteur, Vector, phloem-limited bacteria, plant disease, sap-sucking insect, and weed

Huanglongbing (HLB) is a severe citrus (Citrus spp.) disease associated with the bacteria genus Candidatus Liberibacter, detected in Brazil in 2004. Another bacterium was found in association with HLB symptoms and characterized as a phytoplasma belonging to the 16SrIX group. The objectives of this study were to identify potential leafhopper vectors of the HLB-associated phytoplasma and their host plants. Leafhoppers were sampled every other week for 12 mo with sticky yellow cards placed at two heights (0.3 and 1.5 m) in the citrus tree canopy and by using a sweep net in the ground vegetation of two sweet orange, Citrus sinensis (L.) Osbeck, groves infected by the HLB-phytoplasma in Sao Paulo state. Faunistic analyses indicated one Agalliinae (Agallia albidula Uhler) and three Deltocephalinae [Balclutha hebe (Kirkaldy), Planicephalus flavicosta (Stål), and Scaphytopius (Convelinus) marginelineatus (Stål)] species, as the most abundant and frequent leafhoppers (Hemiptera: Cicadellidae). Visual observations indicated an association of leafhopper species with some weeds and the influence of weed species composition on leafhopper abundance in low-lying vegetation. S. marginelineatus and P. flavicosta were more frequent on Sida rhombifolia L. and Althernantera tenella Colla, respectively, whereas A. albidula was observed more often on Conyza bonariensis (L.) Cronq. and B. hebe only occurred on grasses. DNA samples of field-collected S. marginelineatus were positive by polymerase chain reaction and sequencing tests for the presence of the HLB-phytoplasma group, indicating it as a potential vector. The association of leafhoppers with their hosts may be used in deciding which management strategies to adopt against weeds and diseases in citrus orchards.

Biota, DNA Primers genetics, Databases, Genetic, Ecology methods, Microsatellite Repeats, and Polymorphism, Single Nucleotide

This article documents the addition of 473 microsatellite marker loci and 71 pairs of single-nucleotide polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Barteria fistulosa, Bombus morio, Galaxias platei, Hematodinium perezi, Macrocentrus cingulum Brischke (a.k.a. M. abdominalis Fab., M. grandii Goidanich or M. gifuensis Ashmead), Micropogonias furnieri, Nerita melanotragus, Nilaparvata lugens Stål, Sciaenops ocellatus, Scomber scombrus, Spodoptera frugiperda and Turdus lherminieri. These loci were cross-tested on the following species: Barteria dewevrei, Barteria nigritana, Barteria solida, Cynoscion acoupa, Cynoscion jamaicensis, Cynoscion leiarchus, Cynoscion nebulosus, Cynoscion striatus, Cynoscion virescens, Macrodon ancylodon, Menticirrhus americanus, Nilaparvata muiri and Umbrina canosai. This article also documents the addition of 116 sequencing primer pairs for Dicentrarchus labrax.
(© 2012 Blackwell Publishing Ltd.)

Biomarkers, Tumor metabolism, Female, Humans, Middle Aged, Phosphorylation, Postmenopause, Predictive Value of Tests, Receptors, Estrogen metabolism, Retrospective Studies, Serine metabolism, Treatment Outcome, Antineoplastic Agents, Hormonal pharmacology, Breast Neoplasms drug therapy, Breast Neoplasms metabolism, Proto-Oncogene Proteins c-akt metabolism, TOR Serine-Threonine Kinases metabolism, and Tamoxifen pharmacology

The frequent alterations of the PI3K/Akt/mTOR-growth signaling pathway are proposed mechanisms for resistance to endocrine therapy in breast cancer, partly through regulation of estrogen receptor α (ER) activity. Reliable biomarkers for treatment prediction are required for improved individualized treatment. We performed a retrospective immunohistochemical analysis of primary tumors from 912 postmenopausal patients with node-negative breast cancer, randomized to either tamoxifen or no adjuvant treatment. Phosphorylated (p) Akt-serine (s) 473, p-mTOR-s2448, and ER phosphorylations-s167 and -s305 were evaluated as potential biomarkers of prognosis and tamoxifen treatment efficacy. High expression of p-mTOR indicated a reduced response to tamoxifen, most pronounced in the ER+/progesterone receptor (PgR) + subgroup (tamoxifen vs. no tamoxifen: hazard ratio (HR), 0.86; 95 % confidence interval (CI), 0.31-2.38; P = 0.78), whereas low p-mTOR expression predicted tamoxifen benefit (HR, 0.29; 95 % CI, 0.18-0.49; P = 0.000002). In addition, nuclear p-Akt-s473 as well as p-ER at -s167 and/or -s305 showed interaction with tamoxifen efficacy with borderline statistical significance. A combination score of positive pathway markers including p-Akt, p-mTOR, and p-ER showed significant association with tamoxifen benefit (test for interaction; P = 0.029). Cross-talk between growth signaling pathways and ER-signaling has been proposed to affect tamoxifen response in hormone receptor-positive breast cancer. The results support this hypothesis, as an overactive pathway was significantly associated with reduced response to tamoxifen. A clinical pre-treatment test for cross-talk markers would be a step toward individualized adjuvant endocrine treatment with or without the addition of PI3K/Akt/mTOR pathway inhibitors.

Animals, Bacterial Proteins genetics, Chi-Square Distribution, DNA, Bacterial analysis, DNA, Bacterial genetics, Drug Resistance, Bacterial, Escherichia coli genetics, Escherichia coli isolation purification, Escherichia coli Infections microbiology, Humans, Microbial Sensitivity Tests, beta-Lactamases metabolism, Anti-Bacterial Agents pharmacology, Escherichia coli drug effects, Escherichia coli enzymology, Meat microbiology, Poultry microbiology, and beta-Lactamases genetics

The concurrent presence of bla CTX-M-1 and bla TEM-52 genes on similar plasmids of Escherichia coli isolated from poultry, chicken meat and humans supports the occurrence of food-borne transmission of extended-spectrum beta-lactamase (ESBL) genes. ESBL-producing E. coli (ESBL-E. coli) are most frequently detected in hospitalised patients and are known to spread in healthcare settings. We hypothesised that poultry-associated (PA) ESBL genes are predominant in the community, where acquisition is fuelled by food contamination, whereas non-PA ESBL genes are predominant in hospitals, with acquisition fuelled by cross-transmission. Then, differences in antimicrobial selective pressure in hospitals and poultry would create differences in co-resistance between PA and non-PA ESBL-E. coli. We, therefore, determined the prevalence and co-resistance of PA and non-PA ESBL-E. coli in community-acquired and nosocomial urinary tract infections in humans and bla CTX-M-1 and bla TEM-52 isolates from poultry. A total of 134 human ESBL-E. coli urine isolates were included in this study. Isolates containing bla CTX-M-1 or bla TEM-52 were considered to be PA, with the remainder being non-PA. Also, 72 poultry ESBL-E. coli were included. Minimum inhibitory concentration (MIC) values were determined by broth microdilution. The prevalence of PA ESBL genes in isolates obtained in general practice and hospitals was 28 % versus 30 % (n.s.). Human PA ESBL-E. coli were more frequently susceptible to ciprofloxacin (51 % vs. 25 %; p = 0.0056), gentamicin (86 % vs. 63 %; p = .0.0082), tobramycin (91 % vs. 34 %; p = 0.0001) and amikacin (98 % vs. 67 %; p = 0.0001) compared to human non-PA ESBL-E. coli. PA ESBL-E. coli are not more prevalent in community acquired than nosocomial urine samples, but are more often susceptible to ciprofloxacin and aminoglycosides than non-PA ESBL-E. coli. This does not support the existence of different reservoirs of ESBL genes.

Escherichia coli isolation purification, Escherichia coli Infections microbiology, Humans, Microbial Sensitivity Tests methods, Microbial Sensitivity Tests standards, Sepsis microbiology, beta-Lactam Resistance, Amoxicillin pharmacology, Anti-Bacterial Agents pharmacology, Clavulanic Acid pharmacology, and Escherichia coli drug effects

Objectives: The CLSI recommends a fixed 2 : 1 ratio of co-amoxiclav for broth microdilution susceptibility testing of Enterobacteriaceae, while EUCAST recommends a fixed 2 mg/L clavulanate concentration. The aims of this study were: (i) to determine the influence of a switch from CLSI to EUCAST methodology on Escherichia coli susceptibility rates; (ii) to compare susceptibility results obtained using EUCAST-compliant microdilution with those from disc diffusion and the Etest; and (iii) to evaluate the clinical outcome of patients with E. coli sepsis treated with co-amoxiclav in relation to the susceptibility results obtained using either method.
Methods: Resistance rates were determined in three laboratories that switched from CLSI to EUCAST cards with the Phoenix system (Becton Dickinson) as well as in 17 laboratories that continued to use CLSI cards with the VITEK 2 system (bioMérieux). In one laboratory, isolates were simultaneously tested by both the Phoenix system and either disc diffusion (n = 471) or the Etest (n = 113). Medical and laboratory records were reviewed for E. coli sepsis patients treated with co-amoxiclav monotherapy.
Results: Only laboratories that switched methodology showed an increase in resistance rates - from 19% in 2010 to 31% in 2011 (P < 0.0001). All isolates that tested susceptible by microdilution were also susceptible by disc diffusion or the Etest, but of 326 isolates that tested resistant by microdilution, 43% and 59% tested susceptible by disc diffusion and the Etest, respectively. Among the 89 patients included there was a better correlation between clinical response and measured MICs using the Phoenix system than the Etest.
Conclusions: EUCAST methodology resulted in higher co-amoxiclav E. coli resistance rates than CLSI methodology, but correlated better with clinical outcome. EUCAST-compliant microdilution and disc diffusion provided discrepant results.

Animals, Bacillus thuringiensis Toxins, Binding Sites, Insect Control, Insect Proteins metabolism, Microvilli metabolism, Peptide Hydrolases metabolism, Proteolysis, Bacterial Proteins metabolism, Endotoxins metabolism, Hemiptera metabolism, and Hemolysin Proteins metabolism

To understand the low toxicity of Cry toxins in planthoppers, proteolytic activation of Cry1Ab in Nilaparvata lugens was studied. The proteolytic processing of Cry1Ab protoxin by N. lugens midgut proteases was similar to that by trypsin activated Cry1Ab. The Cry1Ab processed with N. lugens midgut proteases was highly insecticidal against Plutella xylostella. However, Cry1Ab activated either by trypsin or the gut proteases of the brown planthopper showed low toxicity in N. lugens. Binding analysis showed that activated Cry1Ab bound to brush border membrane vesicles (BBMV) from N. lugens at a significantly lower level than to BBMV from P. xylostella.
(Copyright © 2013 Elsevier Inc. All rights reserved.)

Biomarkers, Tumor metabolism, Breast Neoplasms genetics, Breast Neoplasms metabolism, Cadherins metabolism, Colorectal Neoplasms genetics, Colorectal Neoplasms metabolism, Epithelial-Mesenchymal Transition genetics, Gene Expression Regulation, Neoplastic genetics, Homeodomain Proteins metabolism, Humans, Immunohistochemistry, In Situ Hybridization, Laser Capture Microdissection, Liver Neoplasms secondary, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, Survival Analysis, Transcription Factors metabolism, Zinc Finger E-box-Binding Homeobox 1, Breast Neoplasms physiopathology, Colorectal Neoplasms physiopathology, Epithelial-Mesenchymal Transition physiology, Gene Expression Regulation, Neoplastic physiology, Liver Neoplasms metabolism, MicroRNAs metabolism, and Signal Transduction physiology

The role of the epithelial-mesenchymal transition (EMT) in cancer has been studied extensively in vitro, but involvement of the EMT in tumorigenesis in vivo is largely unknown. We investigated the potential of microRNAs as clinical markers and analyzed participation of the EMT-associated microRNA-200-ZEB-E-cadherin pathway in cancer progression. Expression of the microRNA-200 family was quantified by real-time RT-PCR analysis of fresh-frozen and microdissected formalin-fixed paraffin-embedded primary colorectal tumors, normal colon mucosa, and matched liver metastases. MicroRNA expression was validated by in situ hybridization and after in vitro culture of the malignant cells. To assess EMT as a predictive marker, factors considered relevant in colorectal cancer were investigated in 98 primary breast tumors from a treatment-randomized study. Associations between the studied EMT-markers were found in primary breast tumors and in colorectal liver metastases. MicroRNA-200 expression in epithelial cells was lower in malignant mucosa than in normal mucosa, and was also decreased in metastatic compared to non-metastatic colorectal cancer. Low microRNA-200 expression in colorectal liver metastases was associated with bad prognosis. In breast cancer, low levels of microRNA-200 were related to reduced survival and high expression of microRNA-200 was predictive of benefit from radiotheraphy. MicroRNA-200 was associated with ER positive status, and inversely correlated to HER2 and overactivation of the PI3K/AKT pathway, that was associated with high ZEB1 mRNA expression. Our findings suggest that the stability of microRNAs makes them suitable as clinical markers and that the EMT-related microRNA-200-ZEB-E-cadherin signaling pathway is connected to established clinical characteristics and can give useful prognostic and treatment-predictive information in progressive breast and colorectal cancers.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Chimie, Chemistry, Chimie generale et chimie physique, General and physical chemistry, Théorie des réactions, cinétique générale. Catalyse. Nomenclature, documentation chimique, informatique chimique, Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry, Catalyse, Catalysis, Réactions catalytiques, Catalytic reactions, Sciences appliquees, Applied sciences, Physicochimie des polymeres, Physicochemistry of polymers, Polymères organiques, Organic polymers, Propriétés et caractérisation, Properties and characterization, Propriétés des solutions et des gels, Solution and gel properties, Activité catalytique, Catalyst activity, Actividad catalítica, Agrégation moléculaire, Molecular aggregation, Agregación molecular, Aldolisation, Aldol condensation, Aldolización, Aminoacide, Aminoacid, Aminoácido, Catalyse asymétrique, Asymmetric catalysis, Catálisis asimétrica, Composé chiral, Chiral compound, Compuesto quiral, Composé marqué, Labelled compound, Compuesto marcado, Copolymère greffé, Graft copolymer, Copolímero injertado, Cyclanone, Cycloalkanone, Ciclanona, Dérivé du benzaldéhyde, Benzaldehyde derivatives, Benzaldehído derivado, Enantiosélectivité, Enantioselectivity, Enantioselectividad, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Etude expérimentale, Experimental study, Estudio experimental, Marqueur fluorescent, Fluorescent tracer, Marcador fluorescente, Méthacrylate copolymère, Methacrylate copolymer, Metacrilato copolímero, Nanoencapsulation, Nanoencapsulación, Nanoparticule, Nanoparticle, Nanopartícula, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Reconnaissance moléculaire, Molecular recognition, Reconocimiento molecular, Solution aqueuse, Aqueous solution, Solución acuosa, Spectre dichroïsme circulaire, Circular dichroism spectrum, Espectro dicroismo circular, Dérivé de la proline, Particule monomoléculaire, aldol reaction, benzene-1,3,5-tricaboxamide, molecular recognition, organocatalysis, and single-chain polymeric nanoparticles

Here, a modular approach is reported to introduce a specific function into single-chain polymeric nanoparticles (SCPNs). Hereto, an amphiphilic polymer with pendant benzene-1,3,5-tri-carboxamide (BTA) units is mixed with a free BTA that contains a functional group, either a fluorescent naphthalimide or a catalytically active L-proline. Taking advantage of hydrophobic interactions and self-recognition properties of the BTA units, the free BTAs are captured into the interior of the SCPN in water as evidenced by fluorescence studies. To illustrate that function can be readily introduced using a modular approach, L-proline-based BTAs are incorporated to procure a catalytically active SCPN in water. The aldol reaction between p-nitrobenzaldehyde and cyclohexanone shows good conversions at low catalyst loadings and substrate concentrations, and high stereoselectivities are obtained (de = 91% and ee = 98%).

Androstadienes therapeutic use, Antineoplastic Agents, Hormonal pharmacology, Aromatase Inhibitors therapeutic use, Biomarkers, Tumor genetics, Breast pathology, Breast Neoplasms genetics, Breast Neoplasms pathology, Cell Line, Tumor, Cell Proliferation drug effects, Cell Survival drug effects, Enzyme Activators pharmacology, ErbB Receptors antagonists inhibitors, Erlotinib Hydrochloride, Estrogen Receptor alpha antagonists inhibitors, Estrogen Receptor alpha genetics, Female, Gene Expression Regulation, Neoplastic, Genetic Association Studies, Genetic Variation, Humans, Letrozole, MCF-7 Cells, Nitriles therapeutic use, Protein Kinase Inhibitors pharmacology, Quinazolines pharmacology, RNA Interference, RNA, Small Interfering, Tamoxifen pharmacology, Tamoxifen therapeutic use, Toremifene pharmacology, Toremifene therapeutic use, Triazoles therapeutic use, Breast Neoplasms drug therapy, Drug Resistance, Neoplasm genetics, Estrogen Receptor alpha metabolism, Indazoles pharmacology, and Proto-Oncogene Proteins c-vav genetics

Introduction: Endocrine therapies targeting cell proliferation and survival mediated by estrogen receptor α (ERα) are among the most effective systemic treatments for ERα-positive breast cancer. However, most tumors initially responsive to these therapies acquire resistance through mechanisms that involve ERα transcriptional regulatory plasticity. Herein we identify VAV3 as a critical component in this process.
Methods: A cell-based chemical compound screen was carried out to identify therapeutic strategies against resistance to endocrine therapy. Binding to ERα was evaluated by molecular docking analyses, an agonist fluoligand assay and short hairpin (sh)RNA-mediated protein depletion. Microarray analyses were performed to identify altered gene expression. Western blot analysis of signaling and proliferation markers, and shRNA-mediated protein depletion in viability and clonogenic assays, were performed to delineate the role of VAV3. Genetic variation in VAV3 was assessed for association with the response to tamoxifen. Immunohistochemical analyses of VAV3 were carried out to determine its association with therapeutic response and different tumor markers. An analysis of gene expression association with drug sensitivity was carried out to identify a potential therapeutic approach based on differential VAV3 expression.
Results: The compound YC-1 was found to comparatively reduce the viability of cell models of acquired resistance. This effect was probably not due to activation of its canonical target (soluble guanylyl cyclase), but instead was likely a result of binding to ERα. VAV3 was selectively reduced upon exposure to YC-1 or ERα depletion, and, accordingly, VAV3 depletion comparatively reduced the viability of cell models of acquired resistance. In the clinical scenario, germline variation in VAV3 was associated with the response to tamoxifen in Japanese breast cancer patients (rs10494071 combined P value = 8.4 × 10-4). The allele association combined with gene expression analyses indicated that low VAV3 expression predicts better clinical outcome. Conversely, high nuclear VAV3 expression in tumor cells was associated with poorer endocrine therapy response. Based on VAV3 expression levels and the response to erlotinib in cancer cell lines, targeting EGFR signaling may be a promising therapeutic strategy.
Conclusions: This study proposes VAV3 as a biomarker and a rationale for its use as a signaling target to prevent and/or overcome resistance to endocrine therapy in breast cancer.

In Arabidopsis thaliana, seven cyclin-dependent kinase (CDK) inhibitors have been identified, designated interactors of CDKs or Kip-related proteins (KRPs). Here, the function of KRP6 was investigated during cell cycle progression in roots infected by plant-parasitic root-knot nematodes. Contrary to expectations, analysis of Meloidogyne incognita-induced galls of KRP6-overexpressing lines revealed a role for this particular KRP as an activator of the mitotic cell cycle. In accordance, KRP6-overexpressing suspension cultures displayed accelerated entry into mitosis, but delayed mitotic progression. Likewise, phenotypic analysis of cultured cells and nematode-induced giant cells revealed a failure in mitotic exit, with the appearance of multinucleated cells as a consequence. Strong KRP6 expression upon nematode infection and the phenotypic resemblance between KRP6 overexpression cell cultures and root-knot morphology point toward the involvement of KRP6 in the multinucleate and acytokinetic state of giant cells. Along these lines, the parasite might have evolved to manipulate plant KRP6 transcription to the benefit of gall establishment.
(© 2014 American Society of Plant Biologists. All rights reserved.)

Aged, Female, Genome, Human, Genome-Wide Association Study, Hemochromatosis complications, Hemochromatosis pathology, Hemochromatosis Protein, Homozygote, Humans, Iron metabolism, Male, Middle Aged, Polymorphism, Single Nucleotide, Risk Factors, Hemochromatosis genetics, Histocompatibility Antigens Class I genetics, Liver Cirrhosis genetics, Membrane Proteins genetics, and Subtilisins genetics

Genome-wide association studies (GWAS) have revealed genetic determinants of iron metabolism, but correlation of these with clinical phenotypes is pending. Homozygosity for HFE C282Y is the predominant genetic risk factor for hereditary hemochromatosis (HH) and may cause liver cirrhosis. However, this genotype has a low penetrance. Thus, detection of yet unknown genetic markers that identify patients at risk of developing severe liver disease is necessary for better prevention. Genetic loci associated with iron metabolism (TF, TMPRSS6, PCSK7, TFR2 and Chr2p14) in recent GWAS and liver fibrosis (PNPLA3) in recent meta-analysis were analyzed for association with either liver cirrhosis or advanced fibrosis in 148 German HFE C282Y homozygotes. Replication of associations was sought in additional 499 Austrian/Swiss and 112 HFE C282Y homozygotes from Sweden. Only variant rs236918 in the PCSK7 gene (proprotein convertase subtilisin/kexin type 7) was associated with cirrhosis or advanced fibrosis (P = 1.02 × 10(-5)) in the German cohort with genotypic odds ratios of 3.56 (95% CI 1.29-9.77) for CG heterozygotes and 5.38 (95% CI 2.39-12.10) for C allele carriers. Association between rs236918 and cirrhosis was confirmed in Austrian/Swiss HFE C282Y homozygotes (P = 0.014; ORallelic = 1.82 (95% CI 1.12-2.95) but not in Swedish patients. Post hoc combined analyses of German/Swiss/Austrian patients with available liver histology (N = 244, P = 0.00014, ORallelic = 2.84) and of males only (N = 431, P = 2.17 × 10(-5), ORallelic = 2.54) were consistent with the premier finding. Association between rs236918 and cirrhosis was not confirmed in alcoholic cirrhotics, suggesting specificity of this genetic risk factor for HH. PCSK7 variant rs236918 is a risk factor for cirrhosis in HH patients homozygous for the HFE C282Y mutation.
(© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)