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61.
D. A. Pavlov N. G. Emel’yanova Vo Thi Ha Luong Thi Bich Thuan 《Journal of Ichthyology》2013,53(7):478-485
The growth of individuals is analyzed in the mass tropical species manybar goatfish Parupeneus multifasciatus from the Nha Trang Bay of the South China Sea. The relationship between the body weight and body length is determined for the females and males. Among the fishes larger 180 mm fork length (FL), the males prevail. Linear growth of the sagitta is characterized by negative allometry in relation to body length, and sagitta growth in length is faster than in width. Age of fish assessed based on the analysis of daily increments on the sagitta does not exceed three years, and the majority of individuals reach the first sexual maturity by the age of one year. The growth rate of the fish is characterized by a large individual variation. 相似文献
62.
Capsule Populations of most forest bird species increased between 1982 and 2003, probably due to increased forest cover and changes in forest age-class composition. Aims To determine population changes of forest birds in the Czech Republic and to determine their possible causes. Methods Population data were collected via the Breeding Bird Monitoring Programme, which is based on skilled volunteers counting birds at point transects using a standardized technique. Population trends and indices for the period 1982–2003 were calculated for 47 species using log-linear models. Published data on development of forest cover and forest age composition in the Czech Republic were used to indicate environmental change over the same period. Results Populations of most forest species increased between 1982 and 2003. There was also an increase in forest cover and an increase in the proportion of older forest age-classes. The increase in forest specialist birds was positively correlated with the average increase in forest coverage. Conclusions The populations of Czech forest birds have increased in the last two decades. This contrasts with widely reported declines of farmland bird populations throughout Europe. The correlation between populations of specialized forest species and extent of forest habitat suggests that changes in land-use are an important factor. However, increasing cover of mature forests could have a similar effect on the populations of specialist species. 相似文献
63.
Nguyen Phuong Thao Le Duc Dat Ninh Thi Ngoc Vu Anh Tu Tran Thi Hong Hanh Phan Thi Thanh Huong Nguyen Xuan Nhiem Bui Huu Tai Nguyen Xuan Cuong Nguyen Hoai Nam Pham Van Cuong Seo Young Yang Sohyun Kim Doobyeong Chae Young-Sang Koh Phan Van Kiem Chau Van Minh Young Ho Kim 《Bioorganic & medicinal chemistry letters》2013,23(6):1823-1827
Three new pyrrole oligoglycosides, astebatheriosides A–C (1–3), and a new furan oligoglycoside, astebatherioside D (4), were isolated from the starfish Asterina batheri by various chromatographic methods. Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, and 4 moderately inhibited IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC50 values of 36.4, 31.6, and 22.8 μM, respectively. 相似文献
64.
Anh Thu Nguyen-Trung Denis Tritsch Catherine Grosdemange-Billiard Michel Rohmer 《Bioorganic & medicinal chemistry letters》2013,23(6):1643-1647
This work is focused on the design of new antimicrobial drugs and on the development of lipophilic inhibitors of the DXR, the second enzyme of the MEP pathway for the biosynthesis of isoprene units in most bacteria, by replacing the phosphonate group of fosmidomycin derivatives by a tetrazoyl moiety capable of multiple hydrogen bonding. The N- and C-substituted tetrazole analogues of phosphonohydroxamate inhibitors were synthesized and tested on the DXR of Escherichia coli. This work points out the hypothesis that the phosphonate/phosphate recognition site might be too rigid to accommodate other functional groups. 相似文献
65.
66.
The Gram‐negative periodontal pathogen Porphyromonas gingivalis produces a family of outer membrane‐anchored proteases, the gingipains, shown to play an essential role in virulence of the organism. The C‐terminal domain (CTD) of gingipains and other secreted proteins is known to be the targeting signal for maturation and translocation of the protein through the outer membrane. The CTD is subsequently cleaved during the secretion process. Multiple alignment of various CTDs failed to define a consensus sequence at the putative CTD processing site. Using mutagenesis, we were able to show that cleavage at the site is not dependent on a specific residue and that recognition of the site is independent of local sequence. Interestingly, length of the junction between the CTD and adjacent Ig‐like subdomain has a critical influence on post‐translational glycan modification of the protein, whereby insertion of additional residues immediately N‐terminal to the cleavage site results in failure of glycan modification and release of soluble protease into the culture medium. Various hypotheses are presented to explain these phenomena. Knowledge of the role CTDs play in maturation of gingipains has broader application for understanding maturation of CTD homologues expressed by bacteria of the Bacteriodetes phylum. 相似文献
67.
Background
Predicting protein subnuclear localization is a challenging problem. Some previous works based on non-sequence information including Gene Ontology annotations and kernel fusion have respective limitations. The aim of this work is twofold: one is to propose a novel individual feature extraction method; another is to develop an ensemble method to improve prediction performance using comprehensive information represented in the form of high dimensional feature vector obtained by 11 feature extraction methods.Methodology/Principal Findings
A novel two-stage multiclass support vector machine is proposed to predict protein subnuclear localizations. It only considers those feature extraction methods based on amino acid classifications and physicochemical properties. In order to speed up our system, an automatic search method for the kernel parameter is used. The prediction performance of our method is evaluated on four datasets: Lei dataset, multi-localization dataset, SNL9 dataset and a new independent dataset. The overall accuracy of prediction for 6 localizations on Lei dataset is 75.2% and that for 9 localizations on SNL9 dataset is 72.1% in the leave-one-out cross validation, 71.7% for the multi-localization dataset and 69.8% for the new independent dataset, respectively. Comparisons with those existing methods show that our method performs better for both single-localization and multi-localization proteins and achieves more balanced sensitivities and specificities on large-size and small-size subcellular localizations. The overall accuracy improvements are 4.0% and 4.7% for single-localization proteins and 6.5% for multi-localization proteins. The reliability and stability of our classification model are further confirmed by permutation analysis.Conclusions
It can be concluded that our method is effective and valuable for predicting protein subnuclear localizations. A web server has been designed to implement the proposed method. It is freely available at http://bioinformatics.awowshop.com/snlpred_page.php. 相似文献68.
Thi My Lien Do Anh Vu Truong Thi Nga Vo Travis G. Pinnock Lawrence M. Pratt Dominique Guillaume Kim Phi Phung Nguyen 《Phytochemistry letters》2013,6(4):544-551
Boerhaavia diffusa L. is used in the traditional medicine of several Asian countries. The isolation and identification of five new compounds, together with 11 known compounds, from the ethyl acetate extract of the aerial part of B. diffusa grown Vietnam is reported. The structure of the new compounds was established by 1D and 2D NMR spectroscopy, and high resolution ESI-MS analysis. New compounds are two rotenoids: 9,11-dihydroxy-6,10-dimethoxy[1]benzopyrano[3,4-b][1]benzopyran-12(6H)-one (boeravinone P, 3) and 3-[2-(β-d-glucopyranosyloxy)-3-hydroxyphenyl]-5-hydroxy-2-hydroxymethyl-7-methoxy-6-methyl-4H-1-benzopyran-4-one (boeravinone Q, 9), an atropisomeric mixture of two rotenoid glycosides (3′,5-dihydroxy-2-hydroxymethyl-7-methoxy-6-methylisoflavone 2′-O-β-d-glucopyranoside, 11), a sesquiterpene lactone (4,10-dihydroxy-8-methoxyguai-7(11)-en-8,12-olide, 5) and a new phenylpropanoid glycoside (boerhaavic acid, 15). 相似文献
69.
Functional analysis of a cold-responsive rice WRKY gene, <Emphasis Type="Italic">OsWRKY71</Emphasis>
70.
Mithun Das Jin Sha Bertha Hidalgo Stella Aslibekyan Anh N. Do Degui Zhi Dianjianyi Sun Tao Zhang Shengxu Li Wei Chen Sathanur R. Srinivasan Hemant K. Tiwari Devin Absher Jose M. Ordovas Gerald S. Berenson Donna K. Arnett Marguerite R. Irvin 《PloS one》2016,11(1)
In this study, we conducted an epigenome-wide association study of metabolic syndrome (MetS) among 846 participants of European descent in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN). DNA was isolated from CD4+ T cells and methylation at ~470,000 cytosine-phosphate-guanine dinucleotide (CpG) pairs was assayed using the Illumina Infinium HumanMethylation450 BeadChip. We modeled the percentage methylation at individual CpGs as a function of MetS using linear mixed models. A Bonferroni-corrected P-value of 1.1 x 10−7 was considered significant. Methylation at two CpG sites in CPT1A on chromosome 11 was significantly associated with MetS (P for cg00574958 = 2.6x10-14 and P for cg17058475 = 1.2x10-9). Significant associations were replicated in both European and African ancestry participants of the Bogalusa Heart Study. Our findings suggest that methylation in CPT1A is a promising epigenetic marker for MetS risk which could become useful as a treatment target in the future. 相似文献