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971.
972.
Steig?E.?JohnsonEmail author Adam?D.?Gordon Rebecca?M.?Stumpf Deborah?J.?Overdorff Patricia?C.?Wright 《International journal of primatology》2005,26(6):1399-1416
Sexual dimorphism in body size and canine weaponry is commonly associated with high levels of male-male competition. When
group living species do not rely heavily on male-male competition for access to females, sperm competition may represent a
viable alternative strategy. Unlike most haplorhine primates, lemurs are typically monomorphic in body weight and canine height.
We assessed variability of body mass dimorphism and canine size dimorphism in brown lemurs using morphometric data from 3
populations in southeastern Madagascar: Eulemur fulvus rufus, E. albocollaris, and hybrids of the species. We found significant male-biased canine dimorphism in E. albocollaris in conjunction with body-size monomorphism. We observed similar patterns in the hybrids, but E. fulvus rufus exhibited significant female-biased size dimorphism and canine monomorphism. Testes volume was relatively high across study
populations. Thus, sperm competition appears to be strong in brown lemurs. E. albocollaris males combine sperm competition with large canines, but not higher body mass, indicating a difference in sexual strategy
from most lemurs. Patterns of body mass and canine size dimorphism are not uniform across brown lemur populations, indicating
that future work on these populations can explicitly test models that predict relationships between size dimorphism and various
types of competition. 相似文献
973.
The quest to order and classify protein structures has lead to various classification schemes, focusing mostly on hierarchical relationships between structural domains. At the coarsest classification level, such schemes typically identify hundreds of types of fundamental units called folds. As a result, we picture protein structure space as a collection of isolated fold islands. It is obvious, however, that many protein folds share structural and functional commonalities. Locating those commonalities is important for our understanding of protein structure, function, and evolution. Here, we present an alternative view of the protein fold space, based on an interfold similarity measure that is related to the frequency of fragments shared between folds. In this view, protein structures form a complicated, crossconnected network with very interesting topology. We show that interfold similarity based on sequence/structure fragments correlates well with similarities of functions between protein populations in different folds. 相似文献
974.
Green DE Ferreira CL Stick RV Patrick BO Adam MJ Orvig C 《Bioconjugate chemistry》2005,16(6):1597-1609
Gallium and indium complexes with pendant carbohydrates have been prepared and examined for their potential as radiopharmaceuticals. Carbohydrate-bearing 3-hydroxy-4-pyridinone ligand precursors and their tris(ligand)gallium(III) and -indium(III) complexes were synthesized and characterized by mass spectrometry, elemental analysis, and (1)H and (13)C NMR spectroscopy, and in the case of one intermediate, by X-ray crystallography. With three equivalents of ligand, neutral complexes formed with the bidentate hydroxypyridinone moiety complexing the gallium(III) and indium(III) metal centers. 相似文献
975.
The type Ialpha inositol polyphosphate 4-phosphatase generates and terminates phosphoinositide 3-kinase signals on endosomes and the plasma membrane 总被引:1,自引:0,他引:1
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Ivetac I Munday AD Kisseleva MV Zhang XM Luff S Tiganis T Whisstock JC Rowe T Majerus PW Mitchell CA 《Molecular biology of the cell》2005,16(5):2218-2233
Endosomal trafficking is regulated by the recruitment of effector proteins to phosphatidylinositol 3-phosphate [PtdIns(3)P] on early endosomes. At the plasma membrane, phosphatidylinositol-(3,4)-bisphosphate [PtdIns(3,4)P2] binds the pleckstrin homology (PH) domain-containing proteins Akt and TAPP1. Type Ialpha inositol polyphosphate 4-phosphatase (4-phosphatase) dephosphorylates PtdIns(3,4)P2, forming PtdIns(3)P, but its subcellular localization is unknown. We report here in quiescent cells, the 4-phosphatase colocalized with early and recycling endosomes. On growth factor stimulation, 4-phosphatase endosomal localization persisted, but in addition the 4-phosphatase localized at the plasma membrane. Overexpression of the 4-phosphatase in serum-stimulated cells increased cellular PtdIns(3)P levels and prevented wortmannin-induced endosomal dilatation. Furthermore, mouse embryonic fibroblasts from homozygous Weeble mice, which have a mutation in the type I 4-phosphatase, exhibited dilated early endosomes. 4-Phosphatase translocation to the plasma membrane upon growth factor stimulation inhibited the recruitment of the TAPP1 PH domain. The 4-phosphatase contains C2 domains, which bound PtdIns(3,4)P2, and C2-domain-deletion mutants lost PtdIns(3,4)P2 4-phosphatase activity, did not localize to endosomes or inhibit TAPP1 PH domain membrane recruitment. The 4-phosphatase therefore both generates and terminates phosphoinositide 3-kinase signals at distinct subcellular locations. 相似文献
976.
Homogeneous amplification nucleobase quenching assay to detect the E474Q LCHAD deficiency mutation 总被引:2,自引:0,他引:2
Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency is a rare and potentially fatal autosomal recessive disorder of fatty acid metabolism. Early institution of dietary therapy is essential and places a premium on rapid diagnosis. Pregnancy with an LCHAD-deficient fetus is often complicated in the third trimester by liver disease, particularly acute fatty liver of pregnancy. All cases of isolated LCHAD deficiency have at least one copy of the E474Q mutation in the gene encoding the alpha-subunit of the mitochondrial trifunctional protein. Previously published methods for detecting this mutation are based upon allele-specific restriction enzyme digestion of a DNA fragment generated by PCR, followed by gel electrophoresis to resolve the products. We have developed a faster and less expensive assay for the E474Q mutation using PCR followed directly by differential melting of a fluorescently labeled oligodeoxyribonucleotide probe, using nucleobase quenching to detect probe hybridization. 相似文献
977.
Petrlová J Blastík O Průsa R Kukacka J Potĕsil D Mikelová R Adam V Zehnálek J Kizek R 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2005,149(2):485-488
Metallothioneins belong to the group of intracellular, high molecular and cysteine-rich proteins whose content increase with increasing concentration of a heavy metal. Here we applied the adsorptive transfer stripping differential pulse voltammetry Brdicka reaction for the determination of metallothionein in human blood serum of patient poisoned by lead and/or treated by platinum. The increased metallothionein concentrations in both cases were observed. 相似文献
978.
Genotoxicity of the volatile anaesthetic desflurane in human lymphocytes in vitro, established by comet assay 总被引:2,自引:0,他引:2
Karpiński TM Kostrzewska-Poczekaj M Stachecki I Mikstacki A Szyfter K 《Journal of applied genetics》2005,46(3):319-324
The aim of the present study was to estimate the genotoxicity of desflurane, applied as a volatile anaesthetic. The potential genotoxicity was determined by the comet assay as the extent of DNA fragmentation in human peripheral blood lymphocytes in vitro. The comet assay detects DNA strand breaks induced directly by genotoxic agents as well as DNA fragmentation due to cell death. Another anaesthetic, halothane, already proved to be a genotoxic agent, was used as a positive control. Both analysed drugs were capable of increasing DNA migration in a dose-dependent manner under experimental conditions applied. The results of the study demonstrated that the genotoxicity of desflurane was comparable with that of halothane. However, considering the pharmacodynamics of both drugs, the genotoxic activity of desflurane may be connected with a less harmful effect on the exposed patients or medical staff. 相似文献
979.
Flaherty P Giaever G Kumm J Jordan MI Arkin AP 《Bioinformatics (Oxford, England)》2005,21(15):3286-3293
MOTIVATION: In haploinsufficiency profiling data, pleiotropic genes are often misclassified by clustering algorithms that impose the constraint that a gene or experiment belong to only one cluster. We have developed a general probabilistic model that clusters genes and experiments without requiring that a given gene or drug only appear in one cluster. The model also incorporates the functional annotation of known genes to guide the clustering procedure. RESULTS: We applied our model to the clustering of 79 chemogenomic experiments in yeast. Known pleiotropic genes PDR5 and MAL11 are more accurately represented by the model than by a clustering procedure that requires genes to belong to a single cluster. Drugs such as miconazole and fenpropimorph that have different targets but similar off-target genes are clustered more accurately by the model-based framework. We show that this model is useful for summarizing the relationship among treatments and genes affected by those treatments in a compendium of microarray profiles. AVAILABILITY: Supplementary information and computer code at http://genomics.lbl.gov/llda. 相似文献
980.
Margolin AA Greshock J Naylor TL Mosse Y Maris JM Bignell G Saeed AI Quackenbush J Weber BL 《Bioinformatics (Oxford, England)》2005,21(15):3308-3311
SUMMARY: This synopsis provides an overview of array-based comparative genomic hybridization data display, abstraction and analysis using CGHAnalyzer, a software suite, designed specifically for this purpose. CGHAnalyzer can be used to simultaneously load copy number data from multiple platforms, query and describe large, heterogeneous datasets and export results. Additionally, CGHAnalyzer employs a host of algorithms for microarray analysis that include hierarchical clustering and class differentiation. AVAILABILITY: CGHAnalyzer, the accompanying manual, documentation and sample data are available for download at http://acgh.afcri.upenn.edu. This is a Java-based application built in the framework of the TIGR MeV that can run on Microsoft Windows, Macintosh OSX and a variety of Unix-based platforms. It requires the installation of the free Java Runtime Environment 1.4.1 (or more recent) (http://www.java.sun.com). 相似文献