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1.
The gobioid fish Apocryptes bato (Hamilton, 1822) is a species of mudskipper found in Bangladesh, India, and Myanmar. The reproductive biology of A. bato including sex ratio, size at sexual maturity, breeding season, fecundity, and condition factor was studied in the Payra River, southern Bangladesh during May 2016 to April 2017. A total of 1,028 specimens (303 males and 725 females) were collected. The overall sex ratio was significantly different from the expected value of 1:1 (male: female = 1:2.39, χ2 = 173.23, p < 0.05). Size at sexual maturity was estimated as 4.9 cm standard length. Monthly variations in gonadosomatic index indicate that the main breeding season is from May to December. There was a significant positive correlation of body length and body weight with fecundity. Fulton's condition factor varied in both sexes and was attributed to variations in GSI with maturity. Breeding season was significantly associated with rainfall, but not air temperature. Our findings should improve management and conservation of this fish in the Payra River and surrounding ecosystems.  相似文献   
2.
Abstract

Triplex-stabilizing effect of a graft copolymer under physiologically relevant conditions has been evaluated and compared with other polyamines. Here we show that the graft copolymer significantly stabilizes triplex DNAs with amazingly higher efficicacy than that of physiological concentrations of spermine and spermidine.  相似文献   
3.
Nuclear pore complex (NPC) is the only corridor for macromolecules exchange between nucleus and cytoplasm. NPC and its components, nucleoporins, play important role in the diverse physiological processes including macromolecule exchange, chromosome segregation, apoptosis and gene expression. Recent reports also suggest involvement of nucleoporins in carcinogenesis. Applying proteomics, we analyzed expression pattern of the NPC components in a newly established esophageal cancer cell line from Persia (Iran), the high-risk region for esophageal cancer. Our results indicate overexpression of Hsc70 and downregulation of subunit alpha type-3 of proteasome, calpain small subunit 1, and eIF5A-1. Among these proteins, Hsc70 and eIF5A-1 are in direct interaction with NPC and involved in the nucleocytoplasmic exchange. Hsc70 plays a critical role as a chaperone in the formation of a cargo–receptor complex in nucleocytoplasmic transport. On the other hand, it is an NPC-associated protein that binds to nucleoporins and contributes in recycling of the nucleocytoplasmic transport receptors in mammals and affects transport of proteins between nucleus and cytoplasm. The other nuclear pore interacting protein: eIF5A-1 binds to the several nucleoporins and participates in nucleocytoplasmic transport. Altered expression of Hsc70 and eIF5A-1 may cause defects in nucleocytoplasmic transport and play a role in esophageal carcinogenesis.  相似文献   
4.
Tumor necrosis factor a (TNFa) is an inflammatory cytokine that plays a crucial role in the immune response and the progression of cervical lesions. There is a growing body of data evaluating the value of a genetic variant in the TNFa gene with the risk of developing cervical cancer. The aim of this study was to explore the association of a variant, TNF-308 G>A, residing in the TNFa gene with cervical cancer. A total of 91 women with cervical cancer and 161 women as the control group were recruited. DNA was extracted, and Taqman®-probes-based assay was used for genotyping. Our results showed that the minor allele frequency was 0.3 in total population, and the frequency of minor allele A was more in the case group compared with the control. The regression models in different genetic models also revealed that the allele A is a potential risk factor for the development of cervical cancer. In particular, in the dominant model, patients with AG and AA genotypes had a higher risk of developing cervical cancer with odds ratio (OR) of 2.75 (95% confidence interval [CI]: 1.57-4.83, <0.001) and OR of 7.27 (95%CI: 2.5-20.8, <0.001), compared with the GG genotype. Moreover, a similar outcome was obtained for smear test results. Our study demonstrated that TNF-308 G>A located on TNF-a was associated with the risk of cervical cancer, supporting further studies in a larger population and multicenter setting to show the value of emerging markers as risk stratification biomarkers in cervical cancer.  相似文献   
5.
A sensitive and specific assay was developed to detect and biological control of bacterial leaf spot of pumpkin, Xanthomonas cucurbitae was identified on the basis of the morphological, biochemical and molecular assay. The antibiotic sensitivity of the isolate showed that, Carbenicillin revealed highest antibacterial activity with 29 ± 0.00 mm zone of inhibition against isolated bacterial strain. Isolated bacterial strains from soil were also identified by biochemical and molecular characterisation. By analysing morphological and biochemical characteristics and 16S rDNA of three bacterial strains isolated from soil was matched 96% with Bacillus subtilis, 98% with Bacillus brevis and 97% with Pseudomonas fluorescens strain. They were subjected to the antagonistic activity against Xanthomonas cucurbitae by disc diffusion method. Among them, B. subtilis showed significant positive antagonistic activity with 17.0 ± 0.28 mm zone of inhibition against Xanthomonas cucurbitae. The presence of DNA sequence related to the hrpD gene successfully amplified in some isolates of Xanthomonas cucurbitae.  相似文献   
6.
Zou J  Young S  Zhu F  Gheyas F  Skeans S  Wan Y  Wang L  Ding W  Billah M  McClanahan T  Coffman RL  Egan R  Umland S 《Genome biology》2002,3(5):research0020.1-research002013

Background

Inhalation of Ascaris suum antigen by allergic monkeys causes an immediate bronchoconstriction and delayed allergic reaction, including a pulmonary inflammatory infiltrate. To identify genes involved in this process, the gene-expression pattern of allergic monkey lungs was profiled by microarrays. Monkeys were challenged by inhalation of A. suum antigen or given interleukin-4 (IL-4) treatment; lung tissue was collected at 4, 18 or 24 h after antigen challenge or 24 h after IL-4. Each challenged monkey lung was compared to a pool of normal, unchallenged monkey lungs.

Results

Of the approximately 40,000 cDNAs represented on the microarray, expression levels of 169 changed by more than 2.5-fold in at least one of the pairwise probe comparisons; these cDNAs encoded 149 genes, of which two thirds are known genes. The largest number of regulated genes was observed 4 h after challenge. Confirmation of differential expression in the original tissue was obtained for 95% of a set of these genes using real-time PCR. Cluster analysis revealed at least five groups of genes with unique expression patterns. One cluster contained genes for several chemokine mediators including eotaxin, PARC, MCP-1 and MCP-3. Genes involved in tissue remodeling and antioxidant responses were also identified as regulated by antigen and IL-4 or by antigen only.

Conclusion

This study provides a large-scale profile of gene expression in the primate lung following allergen or IL-4 challenge. It shows that microarrays, with real-time PCR, are a powerful tool for identifying and validating differentially expressed genes in a disease model.  相似文献   
7.
Khan F 《Biomacromolecules》2004,5(3):1078-1088
UV radiation induced graft copolymerization of methacrylic acid onto natural lignocellulose (jute) fiber was carried out both by "simultaneous irradiation and grafting" and by preirradiation methods using 1-hydroxycyclohexyl-phenyl ketone as a photoinitiator. In the "simultaneous irradiation and grafting" method, the variation of graft weight with UV-radiation time, monomer concentration, and the concentration of photoinitiator was investigated. In the case of the preirradiation method, the incorporation of 2-methyl-2-propene 1-sulfonic acid, sodium salt, into the grafting reaction solution played a most important role in suppressing the homopolymer/gel formation and facilitating graft copolymerization. The optimum value of the reaction parameters on the percentage of grafting was evaluated. In comparison, results showed that the method of graft-copolymer synthesis has significant influence on graft weight. The study on the mechanical and thermal properties of grafted samples was conducted. The results showed that the percentage of grafting has a significant effect on the mechanical and thermal properties in the case of grafted samples. Considering the water absorption property, the jute-poly(methacrylic acid)-grafted sample showed a maximum up to 42% increase in hydrophilicity with respect to that of the "as received" sample. Attenuated total reflection infrared studies indicate that the estimation of the degree of grafting could be achieved by correlating band intensities with the percent graft weight.  相似文献   
8.
The molecular mechanisms of peroxisome biogenesis have begun to emerge; in contrast, relatively little is known about how the organelle functions as cells age. In this report, we characterize age-related changes in peroxisomes of human cells. We show that aging compromises peroxisomal targeting signal 1 (PTS1) protein import, affecting in particular the critical antioxidant enzyme catalase. The number and appearance of peroxisomes are altered in these cells, and the organelles accumulate the PTS1-import receptor, Pex5p, on their membranes. Concomitantly, cells produce increasing amounts of the toxic metabolite hydrogen peroxide, and we present evidence that this increased load of reactive oxygen species may further reduce peroxisomal protein import and exacerbate the effects of aging.  相似文献   
9.
10.
Spinal cord injury (SCI) can induce prolonged spinal cord compression that may result in a reduction of local tissue perfusion, progressive ischemia, and potentially irreversible tissue necrosis. Due to the combination of risk factors and the varied presentation of symptoms, the appropriate method and time course for clinical intervention following SCI are not always evident. In this study, a three-dimensional finite element fluid-structure interaction model of the cervical spinal cord was developed to examine how traditionally sub-clinical compressive mechanical loads impact spinal arterial blood flow. The spinal cord and surrounding dura mater were modeled as linear elastic, isotropic, and incompressible solids, while blood was modeled as a single-phased, incompressible Newtonian fluid. Simulation results indicate that anterior, posterior, and anteroposterior compressions of the cervical spinal cord have significantly different ischemic potentials, with prediction that the posterior component of loading elevates patient risk due to the concomitant reduction of blood flow in the arterial branches. Conversely, anterior loading compromises flow through the anterior spinal artery but minimally impacts branch flow rates. The findings of this study provide novel insight into how sub-clinical spinal cord compression could give rise to certain disease states, and suggest a need to monitor spinal artery perfusion following even mild compressive loading.  相似文献   
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