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41.
Badreldin H. Ali Sirin A. Adham Mohammed Al Za’abi Mostafa I. Waly Javed Yasin Abderrahim Nemmar Nicole Schupp 《PloS one》2015,10(4)
Chrysin (5, 7- dihydroxyflavone) is a flavonoid with several pharmacological properties that include antioxidant, anti-inflammatory and antiapoptotic activities. in this work, we investigated some effects of three graded oral doses of chrysin (10, 50 and 250 mg/kg) on kidney structure and function in rats with experimental chronic renal disease (CKD) induced by adenine (0.25% w/w in feed for 35 days), which is known to involve inflammation and oxidative stress. Using several indices in plasma, urine and kidney homogenates, adenine was found to impair kidney function as it lowered creatinine clearance and increased plasma concentrations of creatinine, urea, neutrophil gelatinase-associated lipocalin and N-Acetyl-beta-D-glucosaminidase activity. Furthermore, it raised plasma concentrations of the uremic toxin indoxyl sulfate, some inflammatory cytokines and urinary albumin concentration. Renal morphology was severely damaged and histopathological markers of inflammation and fibrosis were especially increased. In renal homogenates, antioxidant indices, including superoxide dismutase and catalase activities, total antioxidant capacity and reduced glutathione were all adversely affected. Most of these adenine – induced actions were moderately and dose -dependently mitigated by chrysin, especially at the highest dose. Chrysin did not cause any overt adverse effect on the treated rats. The results suggest that different doses of chrysin produce variable salutary effects against adenine-induced CKD in rats, and that, pending further pharmacological and toxicological studies, its usability as a possible ameliorative agent in human CKD should be considered. 相似文献
42.
Ricardo Godoy Victoria Reyes-García Vincent Vadez Oyunbileg Magvanjav William R. Leonard Thomas McDade Sanjay Kumar Javed Iqbal David Wilkie Susan Tanner Tomás Huanca 《Human ecology: an interdisciplinary journal》2009,37(5):613-628
Unlike neighboring disciplines, anthropology rarely studies how actual future events affect current behavior. Such studies could lay the groundwork for studies of ethno-forecasting. Psychologists argue that people forecast poorly, but some empirical work in cultural anthropology suggests that at least with weather, rural people might make reasonably accurate forecasts. Using data from a small-scale, pre-industrial rural society in the Bolivian Amazon, this study estimates the effects of future weather on the current collection of planted crops and wildlife. If actual future events affect current behavior, then this would suggest that people must forecast accurately. Longitudinal data covering 11 consecutive months (10/2002–8/2003, inclusive) from 311 women and 326 men ≥age 14 in 13 villages of a contemporary society of forager-farmers in Bolivia’s Amazon (Tsimane’) are used. Individual fixed-effect panel linear regressions are used to estimate the effect of future weather (mean hourly temperature and total daily rain) over the next 1–7 days from today on the probability of collecting wildlife (game, fish, and feral plants excluding firewood) and planted farm crops (annuals and perennials) today. Daily weather records come from a town next to the Tsimane’ territory and data on foraging and farming come from scans (behavioral spot observations) and surveys of study participants done during scans. Short-term future weather (≤3 days) affected the probability of collecting planted crops and wildlife today, although the effect was greater on the amount of planted crops harvested today than on the amount of wildlife collected today. Future weather beyond 3 days bore no significant association with the amount of planted crops harvested today nor with the amount of wildlife collected today. After controlling for future and past weather, today’s weather (mean hourly temperature, but not rain) affected the probability of collecting wildlife today, but today’s weather (temperature or rain) did not affect the probability of collecting planted crops today. The study supports prior work by anthropologists suggesting that rural people forecast accurately. If future weather affects the probability of harvesting planted crops and collecting wildlife today, then this suggests that Tsimane’ must forecast accurately. We discuss possible reasons for the finding. The study also supports growing evidence from rural areas of low-income nations that rural people tend to protect their food production and food consumption well against small idiosyncratic shocks or, in our case, against ordinary daily weather that is not extreme. However, the greater responsiveness of daily foraging output compared with daily farming output to today’s weather suggests that foraging might not protect food consumption as well as farming against adverse climate perturbations. 相似文献
43.
44.
Samuel Q. Li Adam T. Cheuk Jack F. Shern Young K. Song Laura Hurd Hongling Liao Jun S. Wei Javed Khan 《PloS one》2013,8(10)
Rhabdomyosarcoma (RMS) is the most common childhood soft tissue sarcoma. Despite advances in modern therapy, patients with relapsed or metastatic disease have a very poor clinical prognosis. Fibroblast Growth Factor Receptor 4 (FGFR4) is a cell surface tyrosine kinase receptor that is involved in normal myogenesis and muscle regeneration, but not commonly expressed in differentiated muscle tissues. Amplification and mutational activation of FGFR4 has been reported in RMS and promotes tumor progression. Therefore, FGFR4 is a tractable therapeutic target for patients with RMS. In this study, we used a chimeric Ba/F3 TEL-FGFR4 construct to test five tyrosine kinase inhibitors reported to specifically inhibit FGFRs in the nanomolar range. We found ponatinib (AP24534) to be the most potent FGFR4 inhibitor with an IC50 in the nanomolar range. Ponatinib inhibited the growth of RMS cells expressing wild-type or mutated FGFR4 through increased apoptosis. Phosphorylation of wild-type and mutated FGFR4 as well as its downstream target STAT3 was also suppressed by ponatinib. Finally, ponatinib treatment inhibited tumor growth in a RMS mouse model expressing mutated FGFR4. Therefore, our data suggests that ponatinib is a potentially effective therapeutic agent for RMS tumors that are driven by a dysregulated FGFR4 signaling pathway. 相似文献
45.
Mohammad Javed Ansari Ahmad Al-Ghamdi Salma Usmani Rahul Kumar Adgaba Nuru Kuldeep Singh Harcharan Singh Dhaliwal 《Acta Physiologiae Plantarum》2013,35(8):2407-2419
Diploid wheat, Triticum monococcum L. (einkorn) is an ideal plant material for wheat functional genomics. Brittle culm mutant was identified by screening of the ethyl methane sulphonate-treated M 2 progenies of a T. monococcum accession pau14087 by banding the plant parts manually. The brittle culm mutant with drooping leaves, early flowering, reduced tiller numbers and susceptible to lodging had also exhibited brittleness in all plant parts than the wild-type parents. Comprehensive mechanical strength, histological, biochemical, scanning electron microscopy, and Fourier transform infrared spectroscopy analyses of brittle culm mutant supplemented and complemented the findings that the mutant had defective cellulose biosynthesis pathway and deposition of cell wall materials on secondary cell wall of mechanical tissues. Microscopic studies demonstrated that the decrease in cellulose contents resulted in the irregular cell wall organization in xylem vessels of leaf vascular bundles. To map the brc5 mutant, mapping populations were developed by crossing the brittle culm mutant with wild Triticum boeoticum acc. pau5088, having non-brittle characters. The brittle culm mutation was mapped between SSR markers, Xcfd39 and Xgwm126 on 5AmL chromosome of T. monococcum, with genetic distances of 2.6 and 4.8 cM, respectively. The brc5 mutant mapped on 5AmL, being distinct from a previously mapped brittle culm mutant in wheat, has been designated as brc5. The work on fine mapping and map-based cloning of brc5 gene regulating synthesis and deposition of cellulose on the secondary cell wall is in progress. 相似文献
46.
Isha Shamshad Muhammad Waqas Maliha Asma Javed Nawab Nayab Gul 《International journal of phytoremediation》2016,18(4):393-398
The green macroalgae present in freshwater ecosystems have attracted a great attention of the world scientists for removal of heavy metals from wastewater. In this mesocosm study, the uptake rates of heavy metals such as cadmium (Cd), nickel (Ni), chromium (Cr), and lead (Pb) by Oedogonium westi (O. westti) were measured. The equilibrium adsorption capabilities of O. westti were different for Cd, Ni, Cr, and Pb (0.974, 0.418, 0.620, and 0.261 mgg–1, respectively) at 18°C and pH 5.0. Furthermore, the removal efficiencies for Cd, Cr, Ni and Pb were observed from 55–95%, 61–93%, 59–89%, and 61–96%, respectively. The highest removal efficiency was observed for Cd and Cr from aqueous solution at acidic pH and low initial metal concentrations. However, the removal efficiencies of Ni and Pb were higher at high pH and high concentrations of metals in aqueous solution. The results summarized that O. westti is a suitable candidate for removal of selected toxic heavy metals from the aqueous solutions. 相似文献
47.
The emergence of numerous genome projects has made the experimental classification of the protein localization almost impossible due to the exponential increase in the number of protein samples. However, most of the applications are merely developed for single-plex and completely ignored the presence of one protein at two or more locations in a cell. In this regard, few attempts were carried out to target Multi-label protein localizations; consequently, undesirable accuracies are achieved. This paper presents a novel approach, in which a discrete feature extraction method is fused with physicochemical properties of amino acids by using Chou's general form of Pseudo Amino Acid Composition. The technique is tested on two benchmark datasets namely: Gpos-mploc and Virus-mPLoc. The empirical results demonstrated that the proposed method yields better results via two examined classifiers i.e. ML-KNN and Rank-SVM. It is established that the proposed model has improved values in all performance measures considered for the comparison. 相似文献
48.
Srivastava AK Srivastava PK Al-Khedhairy AA Musarrat J Shukla Y 《Mutation research》2012,747(1):22-28
Allethrin (C(19)H(26)O(3)) is non-cyano-containing pyrethroid insecticide that is used extensively for controlling flies and mosquitoes. Apart from its neurotoxic effects in non-target species, allethrin is reported to be mutagenic in bacterial systems. In this study, we observed oxidative damage-mediated genotoxicity caused by allethrin in Swiss albino mice. The genotoxic potential of allethrin was evaluated using chromosome aberrations (CAs) and a micronuclei (MN) induction assay as genetic end-points. The oral intubation of allethrin (25 and 50mg/kg b.wt.) significantly induces CAs and MN in mouse bone marrow cells. The DNA-damaging potential of allethrin was estimated in mouse liver using the DNA alkaline unwinding assay (DAUA) and by measuring the levels of 8-hydroxy-2'-deoxy-guanosine (8-OH-dG). Furthermore, a dose-dependent increase in reactive oxygen species (ROS) generation and lipid peroxidation (LPO), with a concurrent decrease in superoxide dismutase (SOD) and catalase, confirm its pro-oxidant potential. The DNA-damaging potential of allethrin was found to be mediated through the modulation of p53, p21, GADD45α and MDM-2. These results confirm the genotoxic and the pro-oxidant potential of allethrin in Swiss albino mice. 相似文献
49.
Skidmore J Atcha Z Boucherat E Castelletti L Chen DW Coppo FT Cutler L Dunsdon RM Heath BM Hutchings R Hurst DN Javed S Martin S Maskell ES Norton D Pemberton DJ Redshaw S Rutter R Sehmi SS Scoccitti T Temple HE Theobald P Ward RW Wilson DM 《Bioorganic & medicinal chemistry letters》2012,22(10):3560-3563
A series of α7 nicotinic acetylcholine receptor full-agonists with a 1,3,4-oxadiazol-2-amine core has been discovered. Systematic exploration of the structure-activity relationships for both α7 potency and selectivity with respect to interaction with the hERG channel are described. Further profiling led to the identification of compound 22, a potent full agonist showing efficacy in the novel object recognition model of cognition enhancement. 相似文献
50.
Jianfan Sun Qaiser Javed Ahmad Azeem Ikram Ullah Muhammad Saifullah Rakhwe Kama Daolin Du 《Ecology and evolution》2020,10(2):832-842
The distribution of invasive and native species in wetlands is determined by hydrological conditions; whereas conditions such as water depth fluctuations, variations in the nutrient concentrations are expected to affect the growth and physiological traits of plants. For the assessment of such effects, we conduct greenhouse experiment with three factors; 1) water depth of 5 cm and 15 cm (static and fluctuated); 2) three levels of nutrient concentrations (i) full‐strength Hoagland solution (N1), (ii) ¼‐strength Hoagland solution (N2), and (iii) 1/8‐strength Hoagland solution (N3); and 3) species, invasive Wedelia trilobata (L.) and its congener, native Wedelia chinensis (Osbeck.) under mono and mixed culture. Water depth of 5 cm combined with any of the nutrient treatments significantly restrained the photosynthesis, intracellular CO2 concentration and leaf chlorophyll of both W. trilobata and W. chinensis. Increase in the water depth to 15 cm with low‐nutrient treatment N3 did not sustain the physiological traits of W. chinensis under mono and mixed planting. A great loss was noted in the growth of W. chinensis at 15 cm static and fluctuated water depth with low‐nutrient treatment (N3) and under mixed culture. In addition, water depth fluctuations with both low‐ and high‐nutrient treatments significantly affected the root‐shoot ratio, relative growth rate, and interspecific interaction among these two species. W. trilobata benefited more from competitive interaction index (CII) under fluctuated water depth at 15 cm with high nutrients, and the value of CII was clearly positive. Therefore, higher competitive ability may contribute to the invasiveness of W. trilobata in wetlands. 相似文献