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91.
92.
Even in the current era of growing technology, the concentration of heavy metals present in drinking water is still not within the recommended limits as set by the regulatory authorities in different countries of the world. Drinking water contaminated with heavy metals namely; arsenic, cadmium, nickel, mercury, chromium, zinc, and lead is becoming a major health concern for public and health care professionals. Occupational exposure to heavy metals is known to occur by the utilization of these metals in various industrial processes and/or contents including color pigments and alloys. However, the predominant source resulting in measurable human exposure to heavy metals is the consumption of contaminated drinking water and the resulting health issues may include cardiovascular disorders, neuronal damage, renal injuries, and risk of cancer and diabetes. The general mechanism involved in heavy metal‐induced toxicity is recognized to be the production of reactive oxygen species resulting oxidative damage and health related adverse effects. Thus utilization of heavy metal‐contaminated water is resulting in high morbidity and mortality rates all over the world. Thereby, feeling the need to raise the concerns about contribution of different heavy metals in various health related issues, this article has discussed the global contamination of drinking water with heavy metals to assess the health hazards associated with consumption of heavy metal‐contaminated water. A relationship between exposure limits and ultimate responses produced as well as the major organs affected have been reviewed. Acute and chronic poisoning symptoms and mechanisms responsible for such toxicities have also been discussed.  相似文献   
93.
The present study was conducted to elaborate vegetation composition structure to analyze role of edaphic and topographic factors on plant species distribution and community formation during 2013–14. A mixture of quadrat and transect methods were used. The size of quadrat for trees shrubs and herbs were 10 × 5, 5 × 2, 1 × 1 meter square respectively. Different phytosociological attribute were measured at each station. Primary results reported 123 plant species belong to 46 families. Asteraceae and Lamiaceae were dominant families with 8 species each. PCORD version 5 were used for Cluster and Two Way Cluster Analyses that initiated 4 plant communities within elevation range of 529–700 m from sea level. Indicator species analyses (ISA) were used to identify indicator species of each community. CANOCO Software (version 4.5) was used to measure the influence of edaphic and topographic variables on species composition, diversity and community formation. Whereas Canonical Correspondence Analysis (CCA) was used to measure the effect of environmental variables which showed elevation and aspect were the stronger environmental variable among topographic and CaCO3 contents, electric conductivity, soil pH were the stronger edaphic factors in determination of vegetation and communities of the Bheer Hills. Grazing pressure was one of the main anthropogenic factors in this regard.  相似文献   
94.
Nano-sized copper particles are widely used in various chemical, physical, and biological fields. However, earlier studies have shown that nano copper particles (40–100 μg/mL) can induce cell toxicity and apoptosis. Therefore, this study was conducted to investigate the role of nano copper in mitochondrion-mediated apoptosis in PK-15 cells. The cells were treated with different doses of nano copper (20, 40, 60, and 80 μg/mL) to determine the effects of apoptosis using acridine orange/ethidium bromide (AO/EB) fluorescence staining and a flow cytometry assay. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in the PK-15 cells were examined using commercially available kits. Moreover, the mRNA levels of the Bax, Bid, Caspase-3, and CYCS genes were assessed by real-time PCR. The results revealed that nano copper exposure induced apoptosis and changed the mitochondrial membrane potential. In addition, nano copper significantly altered the levels of the Bax, Bid, Caspase-3, and CYCS genes at a concentration of 40 μg/mL. To summarize, nano copper significantly (P < 0.05) decreased the level of SOD and increased the level of MDA in PK-15 cells. Altogether, these results suggest that nano copper can play an important role in inducing the apoptotic pathway in PK-15 cells, which may be the mechanism by which nano copper induces nephrotoxicity.  相似文献   
95.
In budding yeast, the monopolin complex mediates sister kinetochore cross‐linking and co‐orientation in meiosis I. The CK1δ kinase Hrr25 is critical for sister kinetochore co‐orientation, but its roles are not well understood. Here, we present the structures of Hrr25 and its complex with the monopolin subunit Mam1. Hrr25 possesses a “central domain” that packs tightly against the kinase C‐lobe, adjacent to the binding site for Mam1. Together, the Hrr25 central domain and Mam1 form a novel, contiguous embellishment to the Hrr25 kinase domain that affects Hrr25 conformational dynamics and enzyme kinetics. Mam1 binds a hydrophobic surface on the Hrr25 N‐lobe that is conserved in CK1δ‐family kinases, suggesting a role for this surface in recruitment and/or regulation of these enzymes throughout eukaryotes. Finally, using purified proteins, we find that Hrr25 phosphorylates the kinetochore receptor for monopolin, Dsn1. Together with our new structural insights into the fully assembled monopolin complex, this finding suggests that tightly localized Hrr25 activity modulates monopolin complex–kinetochore interactions through phosphorylation of both kinetochore and monopolin complex components.  相似文献   
96.
An association between a five-base-pair deletion/insertion DNA polymorphism at the alpha(2) macroglobulin gene (A2M) and late-onset Alzheimer's disease (LOAD) has been recently described. We developed a PCR assay to analyze this polymorphism in 190 LOAD patients (older than 65 years) and 400 controls from Spain. Controls were stratified into three groups: <65 years (n = 200), 65 to 80 years (n = 100), and 81 years or older (n = 100). We found a significantly higher frequency of carriers of the D allele in patients older than 81 years compared to controls older than 81 years (p = 0.0012). In addition, the frequency of the D allele was significantly lower in controls older than 81 years compared to controls younger than 65 (p = 0.048). Our work suggests that the D allele confers an age-dependent increased risk to develop late-onset Alzheimer's disease.  相似文献   
97.
98.
Melanin is the major factor that determines skin color and protects from ultraviolet radiation. In present study we evaluated the anti‐melanogenesis effect of acetazolamide (ACZ) using four different approaches: enzyme kinetic, in vitro, in vivo and in silico. ACZ demonstrated significant inhibitory activity (IC50 7.895 ± 0.24 μm ) against tyrosinase as compared to the standard drug kojic acid (IC50 16.84 ± 0.64 μm ) and kinetic analyses showed that ACZ is a non‐competitive inhibitor without cytotoxic effect. In in vitro experiments, A375 human melanoma cells were treated with 20 or 40 μm of ACZ with or without 50 μm of l ‐DOPA. Western blot results showed that ACZ significantly (< 0.05) decreased the expression level of tyrosinase at 40 μm . Zebrafish embryos were treated with 10, 20 or 40 μm of ACZ and of positive control kojic acid. At 72 h of treatment with ACZ and kojic acid, ACZ significantly (< 0.001) decreased the embryos pigmentation to 40.8% of untreated embryos at the dose of 40 μm of ACZ while kojic acid decreased only 25.0% of pigmentation at the same dose of kojic acid. In silico docking were performed against tyrosinase using PyRx tool. Docking studies suggested that His244, Asn260 and His85 are the major interacting residues in the binding site of the protein. In conclusion, our results suggest that ACZ is a good candidate for the inhibition of melanin and it could be used as a lead for developing the drugs for hyperpigmentary disorders and skin whitening.  相似文献   
99.
The development of soybean meal (SBM) induced enteritis in the hindgut of the omnivorous common carp (Cyprinus carpio L.). The developed condition was assessed when carp, continuously fed on animal protein, were transferred to a diet in which 20% of the protein was replaced by SBM. After week 1, most of the inflammation parameters were already present, but at week 3, a strong aggravation of the condition was observed which included a shortening of the mucosal folds, the disappearance of the supranuclear vacuoles, an increased number of goblet cells, a thickened lamina propria and sub-epithelial mucosa with increased numbers of basophilic granulocytes as well as a decreased uptake capacity of enterocytes (impaired endocytosis and microvilli). Contrary to previous observations made with respect to Atlantic salmon, common carp start to recover from the fourth to the fifth week after switching to SBM feeding. At this stage, the supranuclear vacuoles refill and most of the parameters revert to basal levels. During the enteritis process, a real-time quantitative PCR analysis was conducted to measure the expression of inflammatory and anti-inflammatory cytokine genes in the isolated intraepithelial lymphocytes (IEL). The pro-inflammatory interleukin 1 beta (IL-1 beta) and tumour necrosis factor alpha1 (TNF-alpha1) genes were up-regulated during the inflammation process while the anti-inflammatory interleukin 10 (IL-10) was down-regulated after an initial up-regulation at week 1. Transforming growth factor beta (TGF-beta) expression showed an up-regulation from week 3 onwards despite the high Ct value and the low primer efficiency shown. This study confirms the contribution of IEL (mainly T-like cells) and basophils in the enteritis process. In addition, the results show a clear involvement of up- and down-regulated cytokine genes in both the onset and recovery of the SBM-induced enteritis in the hindgut of carp.  相似文献   
100.
The medicinal plant, Nothapodytes foetida contains a number of important alkaloids like camptothecin (an anticancer drug molecule) but its concentration is less to meet the existing demand of this important molecule, so in an effort for accessible availability of camptothecin. An endophyte (designated ZP5SE) was isolated from the seed of Nothapodytes foetida and was examined as potential source of anticancer drug lead compound i.e. camptothecin, when grown in Sabouraud liquid culture media under shake flask conditions. The presence of anticancer compound (camptothecin) in this fungus was confirmed by chromatographic and spectroscopic methods in comparison with authentic camptothecin. Isolated endophyte (Neurospora crassa) producing camptothecin may become an easily accessible source for the production of precursor anticancer drug molecule in future at large scale.  相似文献   
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