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21.
Chemoattractant receptor‐homologous molecule expressed on Th2 cells (CRTH2) has been involved in several inflammation dependent diseases by mediating the chemotaxis of pro‐inflammatory cells in response to allergy and other responses through PGD2 ligation. This CRTH2‐PGD2 signaling pathway has become a target for treating allergic and type 2 inflammation dependent diseases, with many inhibitors developed to target the PGD2 binding pocket. One of such inhibitors is the ramatroban analog, CT‐133, which exhibited therapeutic potency cigarette smoke‐induced acute lung injury in patients. Nonetheless, the molecular mechanism and structural dynamics that accounts for its therapeutic prowess remain unclear. Employing computational tools, this study revealed that although the carboxylate moiety in CT‐133 and the native agonist PGD2 aided in their stability within the CRTH2 binding pocket, the tetrahydrocarbazole group of CT‐133 engaged in strong interactions with binding pocket residues which could have formed as the basis of the antagonistic advantage of CT‐133. Tetrahydrocarbazole group interactions also enhanced the relative stability CT‐133 within the binding pocket which consequently favored CT‐133 binding affinity. CT‐133 binding also induced an inactive or ‘desensitized’ state in the helix 8 of CRTH2 which could conversely favor the recruitment of arrestin. These revelations would aid in the speedy development of small molecule inhibitors of CRTH2 in the treatment of type 2 inflammation dependent diseases.  相似文献   
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Cadmium (Cd) is highly toxic metal for plant metabolic processes even in low concentration due to its longer half-life and non-biodegradable nature. The current study was designed to assess the bioremediation potential of a Cd-tolerant phytobeneficial bacterial strain Bacillus sp. SDA-4, isolated, characterized and identified from Chakera wastewater reservoir, Faisalabad, Pakistan, together with spinach (as a test plant) under different Cd regimes. Spinach plants were grown with and without Bacillus sp. SDA-4 inoculation in pots filled with 0, 5 or 10 mg kg−1 CdCl2-spiked soil. Without Bacillus sp. SDA-4 inoculation, spinach plants exhibited reduction in biomass accumulation, antioxidative enzymes and nutrient retention. However, plants inoculated with Bacillus sp. SDA-4 revealed significantly augmented growth, biomass accumulation and efficiency of antioxidative machinery with concomitant reduction in proline and MDA contents under Cd stress. Furthermore, application of Bacillus sp. SDA-4 assisted the Cd-stressed plants to sustain optimal levels of essential nutrients (N, P, K, Ca and Mg). It was inferred that the characterized Cd-tolerant PGPR strain, Bacillus sp. SDA-4 has a potential to reduce Cd uptake and lipid peroxidation which in turn maintained the optimum balance of nutrients and augmented the growth of Cd-stressed spinach. Analysis of bioconcentration factor (BCF) and translocation factor (TF) revealed that Bacillus sp. SDA-4 inoculation with spinach sequestered Cd in rhizospheric zone. Research outcomes are important for understanding morpho-physio-biochemical attributes of spinach-Bacillus sp. SDA-4 synergy which might provide efficient strategies to decrease Cd retention in edible plants and/or bioremediation of Cd polluted soil colloids.  相似文献   
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Journal of Plant Growth Regulation - Nickel (Ni) element is strongly phytotoxic at high concentrations for several plants, but due to its dual behavior and complicated chemistry, it has received...  相似文献   
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BReast CAncer gene 1 (BRCA1)—a tumor suppressor gene plays an important role in the DNA repair mechanism. Several BRCA1 variants perturb its structure and function, including synonymous and nonsynonymous single nucleotide polymorphisms (SNPs). In the present study, we performed in-silico analyses of nonsynonymous SNPs (nsSNPs) of the BRCA1 gene. In total, 122 nsSNPs were retrieved from the NCBI SNP database and in-silico analyses were performed using computational prediction tools: SIFT, PROVEAN, Mutation Taster, PolyPhen-2, MutPred, and ConSurf. Of these tools, SIFT, PROVEAN, and Mutation Taster predicted 61 out of 122 nsSNPs as “damaging”, based on structural homology analysis. PolyPhen-2 classified 22 nsSNPs as “probably damaging”. These nsSNPs were further analyzed by MutPred to predict basic molecular mechanisms of amino acid alteration. ConSurf analysis predicted eleven conserved amino acid residues with structural and functional consequences. We identified five amino acid residues in the RING finger domain (L22, C39, H41, C44, and C47) and two in the BRCT domain (P1771 and I1707) with the potential to deter the BRCA1 protein function. This study provides insights into the effect of nsSNPs and amino acid substitutions in BRCA1.

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International Journal of Peptide Research and Therapeutics - Pseudomonas aeruginosa (P. aeruginosa) is a critical healthcare challenge due to its ability to cause persistent infections and the...  相似文献   
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This paper represents an attempt to investigate the mating behaviour of Symmorphus allobrogus, explaining the willingness of male to mount and copulate. The male displays including mode and frequency of antennation and position while copulating, the displays further comprises of intensity and frequency of rejecting behaviour. The presence of the male’s copulatory and postcopulatory courtship studies, understands the maintenance of monandry. The wasp has numerous secondary sexual characters, and the mating behaviour follows a phyletic and the specific sexual mating characters in context of sexual selection. The duration of mating phases and the number of male antennation series during precopulatory, copulatory and postcopulatory phases of mounting, differs significantly. Mating success depends mostly on the activities of male in the premounting phase and the behaviour of both sexes has a roughly equal importance for it in precopulatory phase. While during copulation, activity of male has little influence on its duration; however, behaviour of female has crucial effect, inducing its earlier termination.  相似文献   
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Vegetation analysis provides the prerequisites to understand the overall community structure and function of any ecosystem and is a fundamental requirement for the precise evaluation of biodiversity. Although many studies have assessed floristic attributes of specific areas, there are still unexplored regions, as is the case of the mountain region in the Kashmir Himalayas. Current research highlighted the recent findings of the scientific characterization of floristic and ecological aspects on the forest flora found in the Bhimber hills, Pakistan. Floristically, a total of 93 species belonging to 80 genera in 41 families were recorded. The species distribution patterns across the families were disproportionate with half of the species contributed by 8 families and 25 families were monotypic. Based on the floristic analysis, Asteraceae was the largest family with 12% of species followed by Poaceae with (11%) species. PAST software, a multivariate ecological community analysis was used to classify the species similarities and differences among the different habitat types. According to the habitat wise distribution, 21% of species were growing in the natural forest habitat, while 15% of species were dispersed in highly distributed habitats along roadsides and 8% on pedestrians. In terms of functional diversity, the herbaceous growth form was dominant (58%). The biological spectrum revealed therophytes as the dominant life form as it indicates the disturbed habitat vegetation. The phytogeographical analysis revealed that the maximum (69%) species were native, while the minimum (31%) species were exotic. Thus, the study of these functional and habitat diversity patterns can significantly improve our understanding of the ecological aspects of the flora in the geographical location. This information may additionally be useful in devising management plans to ensure sustainable utilization and better management of forest landscapes in this Himalayan region.  相似文献   
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