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排序方式: 共有405条查询结果,搜索用时 15 毫秒
1.
Excessive intake of essential elements agitates elemental homeostasis resulting in their heterogeneous distribution. Distraction
of these elements in central nervous system (CNS) have been demonstrated in many neurological disorders, which are vital in
generating free radicals, causing oxidative stress, and contributing to neuronal maladies. The developing CNS is highly vulnerable
to environmental agents, including fluoride. Fluorosis is one such disorder ensued from excessive consumption of fluoride
containing water and/or foods that poses a greater threat to the life. Present study offers perturbations caused by fluoride
toxicity on the level of biometal and antioxidant homeostasis and their interactions. Pregnant Wistar rats were exposed to
100- and 200-ppm fluoride (F−) in drinking water and controls with tap water. The pups born to them were used for the study. On 21st postnatal day, the
concentration of fluoride, biometals, and oxidative stress markers were determined in discrete regions of CNS. The levels
of fluoride, copper, and iron increased whereas manganese and zinc were decreased considerably. Among antioxidant enzymes,
catalase, superoxide dismutase, and glutathione peroxidase were decreased and lipid peroxidation was increased with regional
alterations. The correlation coefficient values among oxidative stress markers and biometals were either positive or negative
and showed less significance during correlation. The results confirm that the fluoride provoked oxidative stress and biometal
deformations are synergistic that successively governs the neuronal damage and developing CNS no longer prevents exacerbations
of fluoride. 相似文献
2.
Research on the Bagatha tribe and the Malas and Madigas in India has been done for economic and social planning purposes in regard to family planning. Bagatha are mostly agricultural people where the nuclear family is prevalent and polygamy is popular as well as cousin marriage. The Madigas and Males (Harijans) are lower caste with the 1st being leather workers and the latter being agricultural helpers. The data was collected by direct interview of 202 tribesmen and 202 caste households with women from 15-49 years of age. The data collected on fertility include live births, child survival rate, fetal wastage, husband and wives education, income, and occupations. On mortality, the number of deaths, age at marriage, number of and intervals of pregnancies. As expected, educated and employed families show healthier and higher levels of fertility especially if the wife is educated. The wife shows more of the responsibility for family planning. The age at marriage and the number of pregnancies appears to have little effect on mortality. In the caste group the education level of the husband has little effect on fertility and again the wife has the primary responsibility in using family planning techniques. 相似文献
3.
R Narayanaswamy 《Biosensors & bioelectronics》1991,6(6):467-475
By combining modern fibre optics and opto-electronic instrumentation with chemical and biochemical reagent systems, it has become possible to fabricate optical biosensors. The current state of the art in this development is reviewed in this paper. Many developments describe selective and sensitive methods for sensing bioanalytes and it is likely that such a development will continue to be a very active area of analytical research. However, these biosensing devices can be regarded as successful only if their practicality and reliability can be demonstrated. 相似文献
4.
A chemically defined medium was established for the growth of tissue cultures of Holarrhena antidysenterica. Administration of cholesterol-[4-14C] to 10-day-old callus yielded radioactive 24-methylenecholesterol, 28-isofucosterol, sitosterol, stigmasterol, and conessine, thereby indicating that the conversion of cholesterol into sitosterol is mediated through 24-methylenecholesterol and 28-isofucosterol in this system. 相似文献
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7.
Nanobiotechnology provides novel set of tools to manipulate and enhance crop production using nanoparticles, nanofibres, nanoemulsions, and nanocapsules. Nanomaterials provide a platform to deliver agrochemicals and various macromolecules needed for plant growth enhancement and resistance to stresses. Smart delivery of agrochemicals increases the yield by optimizing water and nutrient conditions. Another added advantage is controlled release and site-directed delivery of agrochemicals. Further enhancement in quality and quantity in agriculture can be achieved by nanoparticle-mediated gene transformation and delivery of macromolecules that induces gene expression in plants. Various types of nanomaterials have been tested so far and the results have been promising in terms of productivity and quality enhancement. 相似文献
8.
Pradeep Kumar Papolu Nagavara Prasad Gantasala Divya Kamaraju Prakash Banakar Rohini Sreevathsa Uma Rao 《PloS one》2013,8(11)
Root knot nematode, Meloidogyne incognita, is an obligate sedentary endoparasite that infects a large number of crop species and causes substantial yield losses. Non-chemical based control strategies for these nematodes are gaining importance. In the present study, we have demonstrated the significance of two FMRFamide like peptide genes (flp-14 and flp-18) for infection and development of resistance to M. incognita through host-derived RNAi. The study demonstrated both in vitro and in planta validation of RNAi-induced silencing of the two genes cloned from J2 stage of M. incognita. In vitro silencing of both the genes interfered with nematode migration towards the host roots and subsequent invasion into the roots. Transgenic tobacco lines were developed with RNAi constructs of flp-14 and flp-18 and evaluated against M. incognita. The transformed plants did not show any visible phenotypic variations suggesting the absence of any off-target effects. Bioefficacy studies with deliberate challenging of M. incognita resulted in 50-80% reduction in infection and multiplication confirming the silencing effect. We have provided evidence for in vitro and in planta silencing of the genes by expression analysis using qRT-PCR. Thus the identified genes and the strategy can be used as a potential tool for the control of M. incognita. This is the first ever report that has revealed the utility of host delivered RNAi of flps to control M. incognita. The strategy can also be extended to other crops and nematodes. 相似文献
9.
Sohela Shah Yonghwan Kim Irina Ostrovnaya Rajmohan Murali Kasmintan A. Schrader Francis P. Lach Kara Sarrel Rohini Rau-Murthy Nichole Hansen Liyng Zhang Tomas Kirchhoff Zsofia Stadler Mark Robson Joseph Vijai Kenneth Offit Agata Smogorzewska 《PloS one》2013,8(6)
Background
SLX4 encodes a DNA repair protein that regulates three structure-specific endonucleases and is necessary for resistance to DNA crosslinking agents, topoisomerase I and poly (ADP-ribose) polymerase (PARP) inhibitors. Recent studies have reported mutations in SLX4 in a new subtype of Fanconi anemia (FA), FA-P. Monoallelic defects in several FA genes are known to confer susceptibility to breast and ovarian cancers.Methods and Results
To determine if SLX4 is involved in breast cancer susceptibility, we sequenced the entire SLX4 coding region in 738 (270 Jewish and 468 non-Jewish) breast cancer patients with 2 or more family members affected by breast cancer and no known BRCA1 or BRCA2 mutations. We found a novel nonsense (c.2469G>A, p.W823*) mutation in one patient. In addition, we also found 51 missense variants [13 novel, 23 rare (MAF<0.1%), and 15 common (MAF>1%)], of which 22 (5 novel and 17 rare) were predicted to be damaging by Polyphen2 (score = 0.65–1). We performed functional complementation studies using p.W823* and 5 SLX4 variants (4 novel and 1 rare) cDNAs in a human SLX4-null fibroblast cell line, RA3331. While wild type SLX4 and all the other variants fully rescued the sensitivity to mitomycin C (MMC), campthothecin (CPT), and PARP inhibitor (Olaparib) the p.W823* SLX4 mutant failed to do so.Conclusion
Loss-of-function mutations in SLX4 may contribute to the development of breast cancer in very rare cases. 相似文献10.
Swati Kaushik Eshita Mutt Ajithavalli Chellappan Sandhya Sankaran Narayanaswamy Srinivasan Ramanathan Sowdhamini 《PloS one》2013,8(2)