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81.
International Journal of Peptide Research and Therapeutics - LL-37 is a 37 amino acid long cationic peptide belonging to the cathelicidin family of antimicrobial peptides. Limited investigations...  相似文献   
82.
International Journal of Peptide Research and Therapeutics - Acinetobacter baumannii is an important pathogen responsible for nosocomial infections worldwide. Trimeric autotransporters, the...  相似文献   
83.
The relationship between the severity of dengue infection and allergy is still obscure. We conducted an electronic search across 12 databases for relevant articles reporting allergic symptoms, dengue infection, and dengue classification. These studies were categorized according to dengue severity and allergy symptoms, and a meta-analysis was performed by pooling the studies in each category. Among the included 57 articles, pruritus was the most common allergic sign followed by non-specified allergy and asthma(28.6%, 13%, and 6.5%, respectively). Despite the reported significant association of dengue with pruritus and total Ig E level(P \ 0.05), in comparison with non-dengue cases and healthy controls, there was no association between the different severe dengue group with pruritus, skin allergy, food allergy or asthma. However,removing the largest study revealed a significant association between asthma with dengue hemorrhagic fever(DHF) rather than dengue fever(DF). In comparison with DF, DHF was associated with Ig E positivity. Furthermore, specific-Ig E level was higher in secondary DF rather than primary DF. There was a possible association between allergy symptoms and dengue severity progression. Further studies are needed to clarify this association.  相似文献   
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The population abundance, infestation, and harmful effects of the aphid Aphis craccivora Koch (Hemiptera: Aphididae) were studied on four bean plant species, namely the country bean (Lablab purpureus var. BARI Seem 1), the yard‐long bean (Vigna sesquipedalis var. BARI Borboti 1), the hyacinth bean (Dolichos lablab var. BARI Seem 6), and the bush bean (Phaseolus vulgaris var. BARI Jar Seem 3). Aphid abundance and infestation on the leaves, inflorescences, flowers, and pods differed significantly among the bean plant species, with P. vulgaris and V. sesquipedalis having the lowest and highest results, respectively. Aphid severity grade and the number of trichomes of the bean plant species were negatively correlated. The duration of the growth stages among the bean plant species were significantly different, with V. sesquipedalis having the shortest durations. Aphid abundance and infestation significantly affected the physical and phytochemical characteristics of the bean plant species. The highest reduction of number of leaves, flower inflorescences, and pod inflorescences per plant, and moisture and chlorophyll content in the leaves was found in L. purpureus. The results for V. sesquipedalis revealed the highest reduction in plant height, seed weight, and pH, while those of D. lablab showed the highest reduction in leaf area.  相似文献   
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Failed oocyte activation has been observed in unexplained infertile (UI) and asthenoteratozoospermic (AT) men. The deficiency of phospholipase C‐zeta (PLCζ) could be a possible reason for such failures and has not been studied yet. We investigated the expression and localization of PLCζ protein in the sperms of patients with UI and AT conditions. The relationships between PLCζ‐related parameters with male age, sperm characteristics, DNA integrity, and cellular maturity were assessed. Semen samples were collected from fertile (n = 40), UI (n = 40), and AT (n = 40) men. Subsequently, semen analysis, DNA fragmentation, hyaluronic acid‐binding ability, and PLCζ level along with its distribution were evaluated using computer‐assisted sperm analyzer, sperm chromatin structure assay (SCSA), hyaluronic acid‐binding assay (HBA), western blot analysis and immunofluorescence microscopy, respectively. Unlike SCSA, the values of HBA, and PLCζ expression were significantly reduced in UI and AT patients compared to fertile men, whereas no significant differences were observed among the experimental groups in terms of PLCζ localization patterns. The regression analysis also showed that HBA is the only variable associated with PLCζ levels. Furthermore, the correlation of male age with PLCζ localization in postacrosomal, equatorial, and acrosomal+postacrosomal+equatorial (A+PA+E) patterns, as well as the relation of normal morphology, with the (A+PA+E) pattern, remained in the regression model. Our findings indicated that reduced PLCζ level along with the increased DNA fragmentation and impaired maturation may be possible etiologies of decreased fertilization in the studied subjects.  相似文献   
89.
Russian Journal of Bioorganic Chemistry - Pyridazines hold considerable interest relative to pharmacologically active molecules. The pyridazine compounds are exhibited different types of...  相似文献   
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Abstract

Several factors may affect erythropoietin (EPO) sugar structures including designing cell culture procedure, pH, concentration of additives, dissolved oxygen, and other physicochemical parameters. In this study, we investigated the influence of changes in effective parameters and compounds on the growth rate of Chinese hamster ovary cell (CHO) cells producing recombinant EPO. Cell culture was performed at different temperature, buffering conditions, and varied concentrations of additives such as pyruvic acid, insulin, GlutaMAX, and sodium butyrate. Results indicated that the optimal temperature and pH were 37?°C and 7.2, respectively. Also, optimal concentrations for pyruvic acid, butyrate, glutamate, and insulin were obtained to be 20?mM, 1?mM, 2?mM, and 40?μg/mL, respectively. Then, cell culture was performed in microcarrier-coated spinner flasks under the optimized condition. The results showed recombinant human EPO (rhEPO) production with adequate purity. Optimization of physicochemical conditions and culture media are important factors to improve the quantity and quality of protein products. This study showed that cell growth and recombinant EPO protein production significantly increased under the optimized conditions. The results of this research can also be used in scale-up to increase the efficiency of EPO production.

Abbreviations: EPO: erythropoietin; CHO cell: Chinese hamster ovary cell; rhEPO: recombinant human EPO; DMEM: modified eagle’s medium; FBS: fetal bovine serum; SDS-PAGE: sodium dodecyl sulfate–polyacrylamide gel electrophoresis; IGF-1: insulin-like growth factor 1  相似文献   
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