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891.
Sindhu Radhakrishna Arup Ballav Goswami Anindya Sinha 《International journal of primatology》2006,27(4):971-982
We assessed the distribution and conservation status of Bengal slow lorises in Assam and Meghalaya in northeastern India. We surveyed forest reserves, plantations, tea estates, and areas bordering forests in 10 districts of the 2 states and sighted slow lorises in only 4 districts in Assam. Disturbances caused by tree felling, road kills by speeding vehicles, and trapping and hunting are the chief survival threats to the species. We emphasize immediate implementation of conservation measures to ensure the future of the species and recommend additional population surveys to define the distributional extent of Bengal slow lorises. 相似文献
892.
The avian clade Passerida was first identified based on DNA-DNA hybridization data [C.G. Sibley, J.E. Ahlquist, Phylogeny and Classification of Birds, 1990, Yale University Press, New Haven, CT]. Monophyly of the Passerida, with the exception of a few taxa, has later been corroborated in several studies; however, the basal phylogenetic relationships have remained poorly understood. In this paper, we review the current knowledge of the phylogenetic relationships within Passerida and present a new phylogeny based on three nuclear introns (myoglobin intron 2, ornithine decarboxylase introns 6 and 7, as well as beta-fibrinogen intron 5). Our findings corroborate recent molecular hypotheses, but also identify several hitherto unrecognized relationships. 相似文献
893.
A secondary metabolite is a chemical compound produced by a limited number of fungal species in a genus, an order, or even phylum. A profile of secondary metabolites consists of all the different compounds a fungus can produce on a given substratum and includes toxins, antibiotics and other outward-directed compounds. Chemotaxonomy is traditionally restricted to comprise fatty acids, proteins, carbohydrates, or secondary metabolites, but has sometimes been defined so broadly that it also includes DNA sequences. It is not yet possible to use secondary metabolites in phylogeny, because of the inconsistent distribution throughout the fungal kingdom. However, this is the very quality that makes secondary metabolites so useful in classification and identification. Four groups of organisms are particularly good producers of secondary metabolites: plants, fungi, lichen fungi, and actinomycetes, whereas yeasts, protozoa, and animals are less efficient producers. Therefore, secondary metabolites have mostly been used in plant and fungal taxonomy, whereas chemotaxonomy has been neglected in bacteriology. Lichen chemotaxonomy has been based on few biosynthetic families (chemosyndromes), whereas filamentous fungi have been analysed for a wide array of terpenes, polyketides, non-ribosomal peptides, and combinations of these. Fungal chemotaxonomy based on secondary metabolites has been used successfully in large ascomycete genera such as Alternaria, Aspergillus, Fusarium, Hypoxylon, Penicillium, Stachybotrys, Xylaria and in few basidiomycete genera, but not in Zygomycota and Chytridiomycota. 相似文献
894.
895.
A dual-tag microarray platform for high-performance nucleic acid and protein analyses 总被引:1,自引:0,他引:1
Ericsson O Jarvius J Schallmeiner E Howell M Nong RY Reuter H Hahn M Stenberg J Nilsson M Landegren U 《Nucleic acids research》2008,36(8):e45
DNA microarrays serve to monitor a wide range of molecular events, but emerging applications like measurements of weakly expressed genes or of proteins and their interaction patterns will require enhanced performance to improve specificity of detection and dynamic range. To further extend the utility of DNA microarray-based approaches we present a high-performance tag microarray procedure that enables probe-based analysis of as little as 100 target cDNA molecules, and with a linear dynamic range close to 105. Furthermore, the protocol radically decreases the risk of cross-hybridization on microarrays compared to current approaches, and it also allows for quantification by single-molecule analysis and real-time on-chip monitoring of rolling-circle amplification. We provide proof of concept for microarray-based measurement of both mRNA molecules and of proteins, converted to tag DNA sequences by padlock and proximity probe ligation, respectively. 相似文献
896.
Engelmark MT Ivansson EL Magnusson JJ Gustavsson IM Wyöni PI Ingman M Magnusson PK Gyllensten UB 《Human genetics》2008,123(5):437-443
Cervical cancer is a multifactorial disease influenced by both environmental and genetic factors. We have previously found
linkage to 9q32 in a genomewide scan of affected sib-pairs (ASPs) with cervical cancer and to the thymic stromal co-transporter
(TSCOT), a candidate gene in this region. Here we examined the contribution of 9q32 and TSCOT to cervical cancer susceptibility using at larger material of 641 ASPs, 278 of which were included in the earlier genome-scan.
Since heritable forms of cancer frequently show stronger genetic effects in families with early onset of disease, we stratified
the ASPs into two groups based on mean age at diagnosis (MAAD) within sib-pairs. Surprisingly, ASPs with high MAAD (30.5–47.5 years)
showed increased sharing at all microsatellite markers at 9q31.1–33.1 and linkage signals of up to MLS = 2.74 for TSCOT SNPs, while ASPs with low MAAD (19–30 years) showed no deviation from random genetic sharing (MLS = 0.00). The difference
in allelic sharing between the two MAAD strata was significant (P < 0.005) and is not likely to be explained by the HLA haplotype, a previously known genetic susceptibility factor for cervical
cancer. Our results indicate locus heterogeneity in the susceptibility to cervical cancer between the two strata, with polymorphisms
in the 9q32 region mainly showing an effect in women with high MAAD. 相似文献
897.
The PPARGC1A Gly482Ser polymorphism is associated with left ventricular diastolic dysfunction in men
Erik Ingelsson Louise Bennet Martin Ridderstråle Marianne Söderström Lennart Råstam Ulf Lindblad 《BMC cardiovascular disorders》2008,8(1):1-9
Background
The objective was to explore the relationship between left ventricular ejection fraction (LVEF) assessed during hospitalization for acute myocardial infarction (MI) and later health-related quality of life (HRQoL).Methods
We used multivariable linear regression to assess the relationship between LVEF and HRQoL in 256 MI patients who responded to the Kansas City Cardiomyopathy Questionnaire (KCCQ), the EQ-5D Index, and the EuroQol Visual Analogue Scale (EQ-VAS) 2.5 years after the index MI.Results
167 patients had normal LVEF (>50%), 56 intermediate (40%–50%), and 33 reduced (<40%). The mean (SD) KCCQ clinical summary scores were 85 (18), 75 (22), and 68 (21) (p <0.001) in the three groups, respectively. The corresponding EQ-5D Index scores were 0.83 (0.18), 0.72 (0.27), and 0.76 (0.14) (p = 0.005) and EQ-VAS scores were 72 (18), 65 (21), and 57 (20) (p = 0.001). In multivariable linear regression analysis age ≥ 70 years, known chronic obstructive pulmonary disease (COPD), subsequent MI, intermediate LVEF, and reduced LVEF were independent determinants for reduced KCCQ clinical summary score. Female sex, medication for angina pectoris at discharge, and intermediate LVEF were independent determinants for reduced EQ-5D Index score. Age ≥ 70 years, COPD, and reduced LVEF were associated with reduced EQ-VAS score.Conclusion
LVEF measured during hospitalization for MI was a determinant for HRQoL 2.5 years later. 相似文献898.
Bergström Lind S Molin M Savitski MM Emilsson L Aström J Hedberg L Adams C Nielsen ML Engström A Elfineh L Andersson E Zubarev RA Pettersson U 《Journal of proteome research》2008,7(7):2897-2910
Phosphorylation of protein tyrosine residues regulates important cell functions and is, when dysregulated, often crucially involved in oncogenesis. It is therefore important to develop and evaluate methods for identifying and studying tyrosine phosphorylated (P-Tyr) proteins. P-Tyr proteins are present at very low concentrations within cells, requiring highly selective enrichment methods to be detected. In this study, we applied immunoaffinity as enrichment step for P-Tyr proteins. Five selected anti-phosphotyrosine antibodies (monoclonal antibodies 4G10, PY100, PYKD1, 13F9 and one polyclonal antiserum) were evaluated with respect to their capability to enrich P-Tyr proteins from cell extracts of the K562 leukemia cell line. The enrichment resulted in the detection of a group of proteins that potentially were tyrosine-phosphorylated (putative P-Tyr proteins). High accuracy identification of actual P-Tyr sites were performed using a highly selective and sensitive liquid chromatography Fourier transform mass spectrometer (LC-FTMS) setup with complementary collision activated dissociation (CAD) and electron capture dissociation (ECD) fragmentations. 4G10 and PY100 antibodies recognized the greatest number of putative P-Tyr proteins in initial screening experiments and were therefore further evaluated and compared in immunoaffinity enrichment of both P-Tyr proteins and peptides. Using the 4G10 antibody for enrichment of proteins, we identified 459 putative P-Tyr proteins by MS. Out of these proteins, 12 were directly verified as P-Tyr proteins by MS analysis of the actual site. Using the PY100 antibody for enrichment of peptides, we detected 67 P-Tyr peptides (sites) and 89 putative P-Tyr proteins. Generally, enrichment at the peptide level made it difficult to reliably determine the identity of the proteins. In contrast, protein identification following immunoaffinity enrichment at the protein level gave greater sequence coverage and thus a higher confidence in the protein identification. By combining all available information, 40 proteins were identified as true P-Tyr proteins from the K562 cell line. In conclusion, this study showed that a combination of immunoaffinity enrichment using multiple antibodies of both intact and digested proteins in parallel experiments is required for best possible coverage of all possible P-Tyr proteins in a sample. 相似文献
899.
Chrtien Simons Jan G.E. van Leeuwen Robert Stemmer Isabel W.C.E. Arends Thomas Maschmeyer Roger A. Sheldon Ulf Hanefeld 《Journal of Molecular Catalysis .B, Enzymatic》2008,54(3-4):67-71
To investigate the full potential of hydrolases for the removal of two amine-protecting groups, 15 different, commercially available lipases, acylases, proteases and esterases were studied for the hydrolyses of N-acetyl and N-formyl protecting groups. In addition to the well-known acylases from porcine kidney and Aspergillus melleus, this screening revealed that porcine liver esterase and the lipases from Rhizomucor miehei and Pseudomonas stutzeri are also catalysts for the hydrolysis of N-acetylalanine. The activity of lipases in this reaction was unexpected, since lipases are commonly believed not to hydrolyse amides. In addition, from these 15 enzymes, three were found to be active in the hydrolysis of N-formylalanine, i.e. porcine liver esterase and the two acylases. This is the first example where esterase is employed to deprotect N-formyl amides. 相似文献
900.
Rosaura Rodicio Ulf Buchwald Hans-Peter Schmitz Jürgen J Heinisch 《Fungal genetics and biology : FG & B》2008,45(4):422-435
KlWSC1, KlWSC2/3 and KlMID2, which encode putative plasma membrane sensors for cell wall integrity signaling in Kluyveromyces lactis, were cloned and characterized. Double and triple deletion mutants show severe cell integrity defects, indicating overlapping functions. The Klwsc1 Klmid2 double deletion phenotype can be suppressed by overexpression of the downstream components KlROM2, KlPKC1 and KlBCK1. KlWsc1 sensor domain analyses showed that an amino-terminal elongation as well as an extension within the cytoplasmic domain are dispensable for function. Heterologous complementation by KlMID2 and KlWSC1 in Saccharomyces cerevisiae is only achieved upon overexpression. In contrast to ScMID2, ScWSC1 complements in K. lactis. Functional studies with chimeric Mid2 constructs indicate that species specificity is mainly conferred by the extracellular domain. Sensor-GFP fusions localize to the plasma membrane, with a cell cycle dependent distribution of KlWsc1-GFP. Both Wsc-type sensors concentrate in discrete spots within the plasma membrane. 相似文献