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431.
Bhawana Mishra Rajender S. Sangwan Smrati Mishra Jyoti S. Jadaun Farzana Sabir Neelam S. Sangwan 《Protoplasma》2014,251(5):1031-1045
Withania somnifera is one of the most important medicinal plant and is credited with various pharmacological activities. In this study, in vitro multiple shoot cultures were exposed to different concentrations (5–300 μM) of cadmium (Cd) as cadmium sulphate to explore its ability to accumulate the heavy metal ion and its impact on the metabolic status and adaptive responses. The results showed that supplemental exposure to Cd interfered with N, P, and K uptake creating N, P, and K deficiency at higher doses of Cd that also caused stunting of growth, chlorosis, and necrosis. The study showed that in vitro shoots could markedly accumulate Cd in a concentration-dependent manner. Enzymatic activities and isozymic pattern of catalase, ascorbate peroxidase, guaiacol peroxidase, peroxidase, glutathione-S-transferase, glutathione peroxidase, monodehydroascorbate reductase, and dehydroascorbate reductase were altered substantially under Cd exposure. Sugar metabolism was also markedly modulated under Cd stress. Various other parameters including contents of photosynthetic pigments, phenolics, tocopherol, flavonoids, reduced glutathione, nonprotein thiol, ascorbate, and proline displayed major inductive responses reflecting their protective role. The results showed that interplay of enzymatic as well as nonenzymatic responses constituted a system endeavor of tolerance of Cd accumulation and an efficient scavenging strategy of its stress implications. 相似文献
432.
Saurabh Prabhu Zaheer Akbar Frederick Harris Katherine Karakoula Robert Lea Farzana Rowther Tracy Warr Timothy Snape 《Bioorganic & medicinal chemistry》2013,21(7):1918-1924
A series of related 2-arylindoles have been evaluated for their anticancer activity against a range of glioblastoma cell lines using a number of different cell-based assays to determine cell viability after treatment with the compounds. The best indoles, which showed comparable activity to cisplatin against a U87MG cell line in the MTS assay, were taken forward and initial studies suggest that their mechanism of action is consistent with the generation of reactive oxygen species followed by autophagic cell death. Furthermore, activity was also observed in glioblastoma short-term cell cultures for the best lead compound and in some cases gave low micromolar IC50s. 相似文献
433.
Sitara S. R. Ajjampur Saravanakumar Puthupalayam Kaliappan Katherine E. Halliday Gokila Palanisamy Jasmine Farzana Malathi Manuel Dilip Abraham Selvi Laxmanan Kumudha Aruldas Anuradha Rose David S. Kennedy William E. Oswald Rachel L. Pullan Sean R. Galagan Kristjana sbjrnsdttir Roy M. Anderson Jayaprakash Muliyil Rajiv Sarkar Gagandeep Kang Judd L. Walson 《PLoS neglected tropical diseases》2021,15(4)
Since 2015, India has coordinated the largest school-based deworming program globally, targeting soil-transmitted helminths (STH) in ~250 million children aged 1 to 19 years twice yearly. Despite substantial progress in reduction of morbidity associated with STH, reinfection rates in endemic communities remain high. We conducted a community based parasitological survey in Tamil Nadu as part of the DeWorm3 Project—a cluster-randomised trial evaluating the feasibility of interrupting STH transmission at three geographically distinct sites in Africa and Asia—allowing the estimation of STH prevalence and analysis of associated factors. In India, following a comprehensive census, enumerating 140,932 individuals in 36,536 households along with geospatial mapping of households, an age-stratified sample of individuals was recruited into a longitudinal monitoring cohort (December 2017-February 2018) to be followed for five years. At enrolment, a total of 6089 consenting individuals across 40 study clusters provided a single adequate stool sample for analysis using the Kato-Katz method, as well as answering a questionnaire covering individual and household level factors. The unweighted STH prevalence was 17.0% (95% confidence interval [95%CI]: 16.0–17.9%), increasing to 21.4% when weighted by age and cluster size. Hookworm was the predominant species, with a weighted infection prevalence of 21.0%, the majority of which (92.9%) were light intensity infections. Factors associated with hookworm infection were modelled using mixed-effects multilevel logistic regression for presence of infection and mixed-effects negative binomial regression for intensity. The prevalence of both Ascaris lumbricoides and Trichuris trichiura infections were rare (<1%) and risk factors were therefore not assessed. Increasing age (multivariable odds ratio [mOR] 21.4, 95%CI: 12.3–37.2, p<0.001 for adult age-groups versus pre-school children) and higher vegetation were associated with an increased odds of hookworm infection, whereas recent deworming (mOR 0.3, 95%CI: 0.2–0.5, p<0.001) and belonging to households with higher socioeconomic status (mOR 0.3, 95%CI: 0.2–0.5, p<0.001) and higher education level of the household head (mOR 0.4, 95%CI: 0.3–0.6, p<0.001) were associated with lower odds of hookworm infection in the multilevel model. The same factors were associated with intensity of infection, with the use of improved sanitation facilities also correlated to lower infection intensities (multivariable infection intensity ratio [mIIR] 0.6, 95%CI: 0.4–0.9, p<0.016). Our findings suggest that a community-based approach is required to address the high hookworm burden in adults in this setting. Socioeconomic, education and sanitation improvements alongside mass drug administration would likely accelerate the drive to elimination in these communities.Trial Registration: . NCT03014167相似文献
434.
Five species of Mononchida and Mononchulus nodicaudatus (v. Daday, 1899) Cobb, 1918 are reported from freshwater sediments at or near Boba Island, Okavango Swamps, Botswana. Illustrations are given for Mylonchulus lacustris (Cobb N.A. in Cobb MX, 1915) Andrássy, 1958, Iotonchus risoceiae (Carvalho, 1955) Andrássy, 1958 and Cobbonchus spec. Two species of Mononchus Bastian, 1865, M. aquaticus Coetzee, 1968 and M. truncatus Bastian, 1865 were also found. The usually rare species M. nodicaudatus was well represented and its juvenile stages are described for the first time. 相似文献
435.
Previous work from this laboratory has shown that isolated chick renal proximal tubule cells possess an Na+-dependent Pi transport system and that Pi uptake is stimulated under gluconeogenic conditions. It is shown in the present paper that gluconeogenesis is associated with a rapid incorporation of Pi into membrane phospholipids, particularly phosphatidylinositol, and some evidence has been obtained for a change in the relative amounts of phosphatidylinositol polyphosphates under gluconeogenic conditions. There is no increase in the total phospholipid phosphate content however, suggesting that pyruvate-induced incorporation of Pi into phospholipids represents accelerated turnover rather than a net increase in synthesis. It is suggested that the stimulation of Na+-dependent Pi uptake by pyruvate is related to the increased rate of phospholipid turnover. Thus Pi transport may be a further example of a physiological system that is influenced by phosphatidylinositol metabolism. The role of phosphatidylinositol phosphates could be to stimulate transfer of transporter molecules from internal stores to the brush-border membrane of the cell. 相似文献
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