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131.
Adel Shalata Maria C. Ramirez Robert J. Desnick Nolan Priedigkeit Christoph Buettner Claudia Lindtner Mohammed Mahroum Muhammad Abdul-Ghani Feng Dong Nazik Arar Olga Camacho-Vanegas Rui Zhang Sandra C. Camacho Ying Chen Mwafaq Ibdah Ralph DeFronzo Virginia Gillespie Kevin Kelley Brian D. Dynlacht Sehyun Kim Marc J. Glucksman Zvi U. Borochowitz John A. Martignetti 《American journal of human genetics》2013
132.
Masato Ohtani Toshiaki Kondo Naoki Tani Saneyoshi Ueno Leong S. Lee Kevin K. S. Ng Norwati Muhammad Reiner Finkeldey Mohamad Na'iem Sapto Indrioko Koichi Kamiya Ko Harada Bibian Diway Eyen Khoo Kensuke Kawamura Yoshihiko Tsumura 《Molecular ecology》2013,22(8):2264-2279
Tropical rainforests in South‐East Asia have been affected by climatic fluctuations during past glacial eras. To examine how the accompanying changes in land areas and temperature have affected the genetic properties of rainforest trees in the region, we investigated the phylogeographic patterns of a widespread dipterocarp species, Shorea leprosula. Two types of DNA markers were used: expressed sequence tag‐based simple sequence repeats and chloroplast DNA (cpDNA) sequence variations. Both sets of markers revealed clear genetic differentiation between populations in Borneo and those in the Malay Peninsula and Sumatra (Malay/Sumatra). However, in the south‐western part of Borneo, genetic admixture of the lineages was observed in the two marker types. Coalescent simulation based on cpDNA sequence variation suggested that the two lineages arose 0.28–0.09 million years before present and that following their divergence migration from Malay/Sumatra to Borneo strongly exceeded migration in the opposite direction. We conclude that the genetic structure of S. leprosula was largely formed during the middle Pleistocene and was subsequently modified by eastward migration across the subaerially exposed Sunda Shelf. 相似文献
133.
Mahim Khan Muhammad Qasim Usman Ali Ashfaq Sobia Idrees Masoud Shah 《Bioinformation》2013,9(14):710-714
Background:
HCV has become a leading cause of liver cirrhosis and hepatocellular carcinoma and is a major health concern worldwide. To date,
there is no vaccine available in the market to tackle this disease, therefore there is a strong need to develop antiviral compounds
that can target all genotypes of HCV with the same efficiency. Medicinal plants have low cost and are less toxic therefore, extracts
of medicinal plants can serve as important antiviral agents against HCV. This study was designed to screen phytochemicals of
Accacia nilotica to find a potent drug candidate that can inhibit HCV infection effectively.Results:
Docking of NS3/4A protease and Flavonoids of Accacia nilotica revealed that most of the flavonoids bound deeply with the active
site of NS3/4A protease. Compound 01 showed a high ranking on docking score. All other compounds also showed reliable
docking scores and had interactions with the binding cavity of NS3/4A protease, suggesting them as a potent drug candidate to
block HCV replication.Conclusion:
To recognize binding interactions of Accacia nilotica phytochemicals with NS3/4A protease, molecular docking was performed to
find potential inhibitor against NS3/4A protease of HCV. After post docking analysis, important interactions were found between
active compounds and active site of NS3/4A protease. It can be concluded from the study that phytochemicals of Accacia nilotica
may serve as a potential drug candidate with relatively simple structural changes against HCV NS3/4A protease. 相似文献
134.
Yong Seong Lee Yun Serk Park Muhammad Anees Young Cheol Kim Yong Hwan Kim 《Biocontrol Science and Technology》2013,23(12):1427-1441
Lysobacter capsici YS1215 is a soil-borne strain that could inhibit the growth of phytopathogenic fungi, including Phytophthora capsici, Rhizoctonia solani and Fusarium oxysporum, as well as root-knot nematodes. The effect of different concentrations of bacterial culture filtrate (BCF) of L. capsici YS1215 on the mortality of second-stage juveniles (J2) of Meloidogyne incognita was studied using 24-well plates. The J2 mortality increased with increasing concentrations of BCF. YS1215 also produces gelatinases in the culture filtrate. To study its role in nematicidal activities, the partial purification and the characterisation of gelatinolytic proteins were done from the culture medium of the YS1215. The partially purified proteins showed three clear bands with molecular weights estimated using zymography to be 255.7, 232.1 and 146.4 kDa. The optimal pH and temperature for the proteins were 8.0 and 40°C, respectively. The activity of the proteins was inhibited by ethylenediaminetetraacetic acid, FeCl3 and 1,10-phenanthroline, whereas it was activated by MnCl2. The proteins may belong to the group of metalloproteases. Moreover, the proteins could hydrolyse skimmed milk, collagen, gelatin and bovine serum albumin (BSA) as substrates, but not casein. The proteins could induce 75% J2 mortality in five days and degrade the J2 bodies. The present study demonstrates the role of the gelatinolytic proteins in the nematicidal potential of L. capsici YS1215. 相似文献
135.
Wiesław Włoch Anna Wilczek Joanna Jura-Morawiec Paweł Kojs Muhammad Iqbal 《Trees - Structure and Function》2013,27(4):879-893
In contrast to common belief, recent studies have confirmed that intrusive growth of fusiform cambial initials has a significant role in the rearrangement of the initials, but does not contribute to the cambial circumference increment. We observed a rapid rearrangement of cambial initials on a long series of transverse sections of the vascular cambium and the wood of a 50-year-old pine (Pinus sylvestris L.) tree. A comparison of cell arrangement in consecutive sections, as well as a critical analysis of tangential reconstructions, has confirmed that changes in cell locations in a group of cells on the tangential surface caused no change in the total tangential width of the whole group. Models illustrating changes in locations of the initials have been proposed, assuming that intrusive growth, which makes the growing initials intrude between the neighbouring initials and their immediate derivatives, is localized on the longitudinal edges of cells. We infer that intrusive growth of the cambial initials in P. sylvestris is not involved in the cambial circumference increment, but plays a significant role in the rearrangement of the initials, probably allowing for a relaxation of shearing strains generated during radial growth. The relationship of intrusive growth with the elimination of initials has been discussed with reference to the frequency of anticlinal divisions. It has been proposed that the occurrence of anticlinal divisions in excess over the actual requirement for increase in the cambial circumference could be due to internal shearing strains. 相似文献
136.
Predation influences prey diversity and productivity while it effectuates the flux and reallocation of organic nutrients into biomass at higher trophic levels. However, it is unknown how bacterivorous protists are influenced by the diversity of their bacterial prey. Using 456 microcosms, in which different bacterial mixtures with equal initial cell numbers were exposed to single or multiple predators (Tetrahymena sp., Poterioochromonas sp. and Acanthamoeba sp.), we showed that increasing prey richness enhanced production of single predators. The extent of the response depended, however, on predator identity. Bacterial prey richness had a stabilizing effect on predator performance in that it reduced variability in predator production. Further, prey richness tended to enhance predator evenness in the predation experiment including all three protists predators (multiple predation experiment). However, we also observed a negative relationship between prey richness and predator production in multiple predation experiments. Mathematical analysis of potential ecological mechanisms of positive predator diversity—functioning relationships revealed predator complementarity as a factor responsible for both enhanced predator production and prey reduction. We suggest that the diversity at both trophic levels interactively determines protistan performance and might have implications in microbial ecosystem processes and services. 相似文献
137.
Ibrar Ahmed Peter J. Matthews Patrick J. Biggs Muhammad Naeem Patricia A. McLenachan Peter J. Lockhart 《Molecular ecology resources》2013,13(5):929-937
Recently, we reported the chloroplast genome‐wide association of oligonucleotide repeats, indels and nucleotide substitutions in aroid chloroplast genomes. We hypothesized that the distribution of oligonucleotide repeat sequences in a single representative genome can be used to identify mutational hotspots and loci suitable for population genetic, phylogenetic and phylogeographic studies. Using information on the location of oligonucleotide repeats in the chloroplast genome of taro (Colocasia esculenta), we designed 30 primer pairs to amplify and sequence polymorphic loci. The primers have been tested in a range of intra‐specific to intergeneric comparisons, including ten taro samples (Colocasia esculenta) from diverse geographical locations, four other Colocasia species (C. affinis, C. fallax, C. formosana, C. gigantea) and three other aroid genera (represented by Remusatia vivipara, Alocasia brisbanensis and Amorphophallus konjac). Multiple sequence alignments for the intra‐specific comparison revealed nucleotide substitutions (point mutations) at all 30 loci and microsatellite polymorphisms at 14 loci. The primer pairs reported here reveal levels of genetic variation suitable for high‐resolution phylogeographic and evolutionary studies of taro and other closely related aroids. Our results confirm that information on repeat distribution can be used to identify loci suitable for such studies, and we expect that this approach can be used in other plant groups. 相似文献
138.
Objectives
Circulating Fibroblast Growth Factor 21 (FGF21) levels are increased in insulin resistant states such as obesity, type 2 diabetes mellitus and gestational diabetes mellitus (GDM). In addition, GDM is associated with serious maternal and fetal complications. We sought to study human cerebrospinal fluid (CSF) and corresponding circulating FGF21 levels in women with gestational diabetes mellitus (GDM) and in age and BMI matched control subjects. We also assessed FGF21 secretion from GDM and control human placental explants.Design
CSF and corresponding plasma FGF21 levels of 24 women were measured by ELISA [12 GDM (age: 26–47 years, BMI: 24.3–36.3 kg/m2) and 12 controls (age: 22–40 years, BMI: 30.1–37.0 kg/m2)]. FGF21 levels in conditioned media were secretion from GDM and control human placental explants were also measured by ELISA.Results
Glucose, HOMA-IR and circulating NEFA levels were significantly higher in women with GDM compared to control subjects. Plasma FGF21 levels were significantly higher in women with GDM compared to control subjects [234.3 (150.2–352.7) vs. 115.5 (60.5–188.7) pg/ml; P<0.05]. However, there was no significant difference in CSF FGF21 levels in women with GDM compared to control subjects. Interestingly, CSF/Plasma FGF21 ratio was significantly lower in women with GDM compared to control subjects [0.4 (0.3–0.6) vs. 0.8 (0.5–1.6); P<0.05]. FGF21 secretion into conditioned media was significantly lower in human placental explants from women with GDM compared to control subjects (P<0.05).Conclusions
The central actions of FGF21 in GDM subjects maybe pivotal in the pathogenesis of insulin resistance in GDM subjects. The significance of FGF21 produced by the placenta remains uncharted and maybe crucial in our understanding of the patho-physiology of GDM and its associated maternal and fetal complications. Future research should seek to elucidate these points. 相似文献139.
140.
This article looks at the steady flow of Micropolar fluid over a stretching surface with heat transfer in the presence of Newtonian heating. The relevant partial differential equations have been reduced to ordinary differential equations. The reduced ordinary differential equation system has been numerically solved by Runge-Kutta-Fehlberg fourth-fifth order method. Influence of different involved parameters on dimensionless velocity, microrotation and temperature is examined. An excellent agreement is found between the present and previous limiting results. 相似文献