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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 EX )+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 L* + P EX The derived R term (R c ), calculated as: R c = C - FU - (P = P L* + P EX ) = 34.84 (6) Daily budgets of an average adult, where ΔP AD reflects the change in body weight and P R =reproductive production, were: C =(ΔP 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 is zero and includes a corrected R term whereby R C =1.43 R M . ΔP AD 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 L* + P EX and A = assimilation + C - FU ) were: net ecological efficiency (P.A. -1 )=56.8%, gross ecological efficiency (P.C -1 )=15.2%, assimilation efficiency (A.C. -1 )=26.8%, P.R. -1 =121.5%. Adult efficiencies were: P. A. -1 =28.6%, 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.

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.

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.

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.

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.)