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TONGUE, MORPHOLOGY, COMPARATIVE anatomy, MUSCLES, and MOUTH

The muscle fibre composition of three human intrinsic tongue muscles, the longitudinalis, verticalis and transversus, was investigated in four anterior to posterior regions of the tongue using morphological and enzyme- and immunohistochemical techniques. All three muscles typically contained type I, IIA and IM/IIC fibres. Type I fibres expressed slow myosin heavy chain (MyHC), type II fibres fast MyHC, mainly fast A MyHC, whereas type IM/IIC coexpressed slow and fast MyHCs. Type II fibres were in the majority (60%), but regional differences in proportion and diameter of fibre types were obvious. The anterior region of the tongue contained a predominance of relatively small type II fibres (71%), in contrast to the posterior region which instead showed a majority of larger type I and type IM/IIC fibres (66%). In general, the fibre diameter was larger in the posterior region. This muscle fibre composition of the tongue differs from those of limb, orofacial and masticatory muscles, probably reflecting genotypic as well as phenotypic functional specialization in oral function. The predominance of type II fibres and the regional differences in fibre composition, together with intricate muscle structure, suggest generally fast and flexible actions in positioning and shaping the tongue, during vital tasks such as mastication, swallowing, respiration and speech.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

PLANT chemical defenses, VIGNA, and COREIDAE

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. [ABSTRACT FROM AUTHOR]

ELECTRICAL steel, ELECTRICAL engineering materials, SILICON steel, STEEL, IRON, and STEEL alloys

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. [ABSTRACT FROM AUTHOR]

BREAST cancer, CANCER in women, CANCER treatment, THERAPEUTICS, TAMOXIFEN, TUMOR growth, and ESTROGEN

Background: Subgroups of breast cancer that have an impaired response to endocrine treatment, despite hormone receptor positivily, 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. [ABSTRACT FROM AUTHOR]

AGRICULTURAL pests, INSECT anatomy, INSECT physiology, INSECT metamorphosis, INSECT development, and DEVELOPMENTAL biology

The five immature stages of Agonoscelis puberula Stål are described and illustrated; biological notes and a new host plant, Leonotis nepefifolia (L.) are also recorded. [ABSTRACT FROM AUTHOR]

HEMIPTERA, COTTON diseases & pests, and STEREOCHEMISTRY

Research was conducted to evaluate the possibility that a plant bug damaging cotton, Gossypium hirsutum L., in south Texas is actually green mind, Creontiades dillutus Stål, which is the primary plant bug pest of cotton in Australia. Molecular comparisons targeting a fragment of the COl region of mitochondrial DNA were made on Creontiades specimens collected from the Lower Rio Grande Valley of Texas and specimens of green mind and brown mind, C. pacificus Stål, collected from Queensland, Australia. The emerging south Texas cotton pest is neither of the species tested from Australia; rather it is a closely related, possibly indigenous species. Further morphological systematics work is needed to identify the Creontiades species from Texas, and collection of additional specimens from several locations where it is known to occur is ongoing. [ABSTRACT FROM AUTHOR]

ETHYLENE glycol, THERMODYNAMICS, HYDROGEN bonding, SUPRAMOLECULAR chemistry, SOLVENTS, and CHEMICAL reduction

Substitution of hydrogen bond directed supramolecular assemblies with ethylene glycol chains leads to a reduction in the association constant in apolar solvents, where the reduction of the association constant is dependent on the length of the aliphatic spacer connecting the hydrogen bonds and the ethylene glycol chain. [ABSTRACT FROM AUTHOR]

BIOLOGICAL pest control, LANTANA camara, PREDICTION theory, BIOCLIMATOLOGY, SPATIAL variation, BIOLOGICAL mathematical modeling, and CHRYSOMELIDAE

Abstract: Understanding the effects of different types and quality of data on bioclimatic modeling predictions is vital to ascertaining the value of existing models, and to improving future models. Bioclimatic models were constructed using the CLIMEX program, using different data types – seasonal dynamics, geographic (overseas) distribution, and a combination of the two – for two biological control agents for the major weed Lantana camara L. in Australia. The models for one agent, Teleonemia scrupulosa Stål (Hemiptera: Tingidae) were based on a higher quality and quantity of data than the models for the other agent, Octotoma scabripennis Guérin-Méneville (Coleoptera: Chrysomelidae). Predictions of the geographic distribution for Australia showed that T. scrupulosa models exhibited greater accuracy with a progressive improvement from seasonal dynamics data, to the model based on overseas distribution, and finally the model combining the two data types. In contrast, O. scabripennis models were of low accuracy, and showed no clear trends across the various model types. These case studies demonstrate the importance of high quality data for developing models, and of supplementing distributional data with species seasonal dynamics data wherever possible. Seasonal dynamics data allows the modeller to focus on the species response to climatic trends, while distributional data enables easier fitting of stress parameters by restricting the species envelope to the described distribution. It is apparent that CLIMEX models based on low quality seasonal dynamics data, together with a small quantity of distributional data, are of minimal value in predicting the spatial extent of species distribution. [Copyright &y& Elsevier]

COMPARTMENT syndrome, THERAPEUTICS, ANALYSIS of variance, CAPILLARIES, CHI-squared test, COMPUTER software, EXERCISE, IMMUNOHISTOCHEMISTRY, LEG, LONGITUDINAL method, MICROCIRCULATION, MUSCLES, RESEARCH funding, STRIATED muscle, T-test (Statistics), DATA analysis, CASE-control method, ANALYTICAL chemistry, PATHOLOGY, DONOR blood supply, and FASCIAE surgery

There is a paucity of data regarding the pathogenesis of chronic exertional compartment syndrome (CECS), its consequences for the muscles and the effects of treatment with fasciotomy. We analyzed biopsies from the tibialis anterior muscle, from nine patients, obtained during a decompressing fasciotomy and during follow-up 1 year later. Control biopsies were obtained from nine normal subjects. Muscle capillarity, fiber-type composition and fiber area were analyzed with enzyme- and immunohistochemistry and morphometry. At baseline, CECS patients had lower capillary density (273 vs 378 capillaries/mm, P=0.008), lower number of capillaries around muscle fibers (4.5 vs 5.7, P=0.004) and lower number of capillaries in relation to the muscle fiber area (1.1 vs 1.5, P=0.01) compared with normal controls. The fiber-type composition and fiber area did not differ, but focal signs of neuromuscular damage were observed in the CECS samples. At 1-year follow-up after fasciotomy, the fiber area and the number of fibers containing developmental myosin heavy chains were increased, but no enhancement of the capillary network was detected. Thus, morphologically, patients with CECS seemed to have reduced microcirculation capacity. Fasciotomy appeared to trigger a regenerative response in the muscle, however, without any increase in the capillary bed. [ABSTRACT FROM AUTHOR]

RHODNIUS, CONENOSES, CLASSIFICATION of insects, and SPECIES diversity

Tribe Rhodniini includes Rhodnius Stål and Psammolestes Bergroth. Enzymatic and molecular evidence suggest the tribe is monophyletic. Most species are wild, living in palms and bird nests. Traditionally both genera were considered related; nevertheless, molecular studies don't support the Rhodnius monophyly. The goal was to phylogenetically analyze morphometric variation in wing architecture in support of Rhodniini taxonomy and systematics. We photographed 524 wings of five representatives of Rhodniini: Psammolestes arthuri (Pinto) (n = 89), Rhodnius pictipes Stål (n = 21), R. robustus Larrousse (n = 24), R. prolixus Stål (n = 16), and R. neivai Lent (n = 22). As outgroups we studied four representatives of Triatomini: Eratyrus mucronatus Stål (n = 15), Panstrongylus rufotuberculatus (Champion) (n = 45), P. geniculatus (Latreille) (n = 183), and Triatoma maculata (Erichson) (n = 109). Landmark coordinate (x, y) configurations were registered and aligned by Generalized Procrustes Analysis. Covariance Analyses were implemented with proportions of re-classified groups and MANOVA. Then, wing shape variables (confidence intervals from relative warps) and centroid size were cladistically analysed. Statistical analyses of variance found not significant differences in wing isometric size (Kruskal-Wallis) among P. arthuri-R. neivai-R. pictipes; R. robustus-R. prolixus-T. maculata and between P. rufotuberculatus-P. geniculatus. The a posteriori re-classification was perfect in E. mucrunatus 100% and R. pictipes, followed by T. maculata 96%, R. neivai 95%, P arthuri 93.2%; R. prolixus 87.5%, P. geniculatus 87.4%, P. rufotuberculatus 84.4%, and R. robustus 76%. Cladistic analyses under parsimony selected two most parsimonious trees (L=4.461 IC=0.973 and IR=0.979), where the strict consensus showed a monophyletic group with Panstrongylus (rufotuberculatus + geniculatus) and Triatoma + Rhodniini (Rhodinus + Psammolestes), but internally it shows the paraphyly of Rhodnius regarding Psammolestes. The congruence between these results and previous molecular analyses in Rhodniini, reveal the phylogenetic information of our morphometric characters as support to systematic studies, allowing the combination of geometric morphometrics and phylogenetic methods for the first time in this group. [ABSTRACT FROM AUTHOR]