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排序方式: 共有601条查询结果,搜索用时 15 毫秒
41.
Yanying Huo Akshada Sawant Yongmei Tan Amar H Mahdi Tao Li Hui Ma Vrushank Bhatt Run Yan Jake Coleman Cheryl F Dreyfus Jessie Yanxiang Guo M. Maral Mouradian Eileen White Bing Xia 《PLoS genetics》2022,18(4)
The PALB2 tumor suppressor plays key roles in DNA repair and has been implicated in redox homeostasis. Autophagy maintains mitochondrial quality, mitigates oxidative stress and suppresses neurodegeneration. Here we show that Palb2 deletion in the mouse brain leads to mild motor deficits and that co-deletion of Palb2 with the essential autophagy gene Atg7 accelerates and exacerbates neurodegeneration induced by ATG7 loss. Palb2 deletion leads to elevated DNA damage, oxidative stress and mitochondrial markers, especially in Purkinje cells, and co-deletion of Palb2 and Atg7 results in accelerated Purkinje cell loss. Further analyses suggest that the accelerated Purkinje cell loss and severe neurodegeneration in the double deletion mice are due to excessive oxidative stress and mitochondrial dysfunction, rather than DNA damage, and partially dependent on p53 activity. Our studies uncover a role of PALB2 in mitochondrial homeostasis and a cooperation between PALB2 and ATG7/autophagy in maintaining redox and mitochondrial homeostasis essential for neuronal survival. 相似文献
42.
Saurabh Kumar Agnihotri Balawant Kumar Ankita Jain Anjali Anjali Mahendra Pal Singh Negi Rekha Sachan Madan Lal Brahma Bhatt Raj Kamal Tripathi Monika Sachdev 《Reports of Biochemistry & Molecular Biology》2022,10(4):711
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms 相似文献
43.
44.
AbstractDesert plant species commonly use seed dormancy to prevent germination during unfavorable environmental conditions and thus increase the probability of seedling survival. Seed dormancy presents a challenge for restoration ecology, particularly in desert species for which our knowledge of dormancy regulation is limited. In the present study the effect of gibberellic acid (GA3) and potassium nitrate (KNO3) on seed dormancy release was investigated on eight Arabian desert species. Both treatments significantly enhanced the germination of most species tested. GA3 was more effective than KNO3 in enhancing germination percentage, reducing mean germination time and synchronizing the germination in most of the studied species. Light requirement during germination was species-specific, but in general the presence of light promoted germination more effectively when combined with KNO3 and GA3. The wide variation in dormancy and germination requirements among the tested species is indicative of distinct germination niches, which might assist their co-existence in similar habitat/environmental conditions. Seed pre-treatments that optimize germination in this habitat must therefore be assessed for individual species to improve the outcomes of ecological restoration. 相似文献
45.
Loss of A-type lamin expression compromises nuclear envelope integrity leading to muscular dystrophy 总被引:28,自引:0,他引:28
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Sullivan T Escalante-Alcalde D Bhatt H Anver M Bhat N Nagashima K Stewart CL Burke B 《The Journal of cell biology》1999,147(5):913-920
The nuclear lamina is a protein meshwork lining the nucleoplasmic face of the inner nuclear membrane and represents an important determinant of interphase nuclear architecture. Its major components are the A- and B-type lamins. Whereas B-type lamins are found in all mammalian cells, A-type lamin expression is developmentally regulated. In the mouse, A-type lamins do not appear until midway through embryonic development, suggesting that these proteins may be involved in the regulation of terminal differentiation. Here we show that mice lacking A-type lamins develop to term with no overt abnormalities. However, their postnatal growth is severely retarded and is characterized by the appearance of muscular dystrophy. This phenotype is associated with ultrastructural perturbations to the nuclear envelope. These include the mislocalization of emerin, an inner nuclear membrane protein, defects in which are implicated in Emery-Dreifuss muscular dystrophy (EDMD), one of the three major X-linked dystrophies. Mice lacking the A-type lamins exhibit tissue-specific alterations to their nuclear envelope integrity and emerin distribution. In skeletal and cardiac muscles, this is manifest as a dystrophic condition related to EDMD. 相似文献
46.
We consider the efficient initialization of structure and parameters of generalized Gaussian radial basis function (RBF) networks using fuzzy decision trees generated by fuzzy ID3 like induction algorithms. The initialization scheme is based on the proposed functional equivalence property of fuzzy decision trees and generalized Gaussian RBF networks. The resulting RBF network is compact, easy to induce, comprehensible, and has acceptable classification accuracy with stochastic gradient descent learning algorithm. 相似文献
47.
Bhatt AN Khan MY Bhakuni V 《Protein science : a publication of the Protein Society》2004,13(8):2184-2195
The serine hydroxymethyltransferase from Bacillus subtilis (bsSHMT) and B. stearothermophilus (bstSHMT) are both homodimers and share approximately 77% sequence identity; however, they show very different thermal stabilities and unfolding pathways. For investigating the role of N- and C-terminal domains in stability and unfolding of dimeric SHMTs, we have swapped the structural domains between bs- and bstSHMT and generated the two novel chimeric proteins bsbstc and bstbsc, respectively. The chimeras had secondary structure, tyrosine, and pyridoxal-5'-phosphate microenvironment similar to that of the wild-type proteins. The chimeras showed enzymatic activity slightly higher than that of the wild-type proteins. Interestingly, the guanidium chloride (GdmCl)-induced unfolding showed that unlike the wild-type bsSHMT, which undergoes dissociation of native dimer into monomers at low guanidium chloride (GdmCl) concentration, resulting in a non-cooperative unfolding of enzyme, its chimera bsbstc, having the C-terminal domain of bstSHMT was resistant to low GdmCl concentration and showed a GdmCl-induced cooperative unfolding from native dimer to unfolded monomer. In contrast, the wild-type dimeric bstSHMT was resistant to low GdmCl concentration and showed a GdmCl-induced cooperative unfolding, whereas its chimera bstbsc, having the C- terminal domain of bsSHMT, showed dissociation of native dimer into monomer at low GdmCl concentration and a GdmCl-induced non-cooperative unfolding. These results clearly demonstrate that the C-terminal domain of dimeric SHMT plays a vital role in stabilization of the oligomeric structure of the native enzyme hence modulating its unfolding pathway. 相似文献
48.
Composting technique was used for bioremediation of industrial soil originating from a former tar-contaminated site. The composting
process was regulated by aeration to keep optimal temperature gradient and concentrations of O2 and CO2 inside the composting pile. The efficiency of bioremediation was evaluated by performing analysis of 11 individual three-
to six-ring unsubstituted aromatic hydrocarbons (PAH) and estimating of changes in ecotoxicity of the contaminated soil. After
42 d of composting, PAH with 3–4 rings were removed from 42 to 68%, other higher-molar mass PAH from 35 to 57%. Additional
100 d of compost maturation in open-air field did not result in a further decrease of PAH. Ecotoxicity tests performed with
bioluminescent bacteriaVibrio fischerii showed a decrease in toxicity both after composting and maturation phases. However, toxicity tests on mustard-seed germination
did not reveal any significant changes during composting and maturation phases. 相似文献
49.
Water temperature and pH influence olfactory sensitivity to pre-ovulatory and post-ovulatory ovarian pheromones in male Barilius bendelisis 总被引:1,自引:0,他引:1
The attractive response and sexual activity elicited by pre-ovulatory steroid sulphate and post-ovulatory 15K-PGF pheromones
are greater in wild caught tubercular males and immature males which express breeding tubercles on the snout (at 12–13 days
post androgen implant) than in non-tubercular and non-androgen implanted males of freshwater fishBarilius bendelisis. This shows that circulatory androgens exert an activational effect on olfactory receptors of male fish. Wild caught tubercular
males and androgen implanted juvenile males exhibit a high responsiveness to steroid sulphate at the water temperature and
pH which fish experience during the pre-spawning phase. The male’s sensitivity to 15K-PGF is almost equally high at the water
temperature and pH which they experience in wild during the both pre-spawning and spawning periods. This suggests that the
differential olfactory sensitivity to the two classes of pheromones in androgen implanted males is due to the varied temperature
and pH of water, and that during the breeding season the male’s olfactory sensitivity to PGF pheromone is more widespread
than to the steroidal pheromone. An increased and decreased olfactory sensitivity in mature males to sex pheromones and L-alanine
respectively during the breeding phase is in agreement with the hypothesis that pheromonal stimuli dominate over feeding stimuli
to promote spawning success. 相似文献
50.
Bhatt T Jain V Jayathirtha MG Banerjee G Mishra SH 《Indian journal of experimental biology》2002,40(12):1382-1386
Adventitious roots, generated using leaf explants of P. nodiflora, and meristem explants of L. reticulata, were cultured on Murashige and Skoog (MS) medium supplemented with napthylacetic acid (2 microM) and indole butyric acid (3 microM) respectively. After 30 days, subculturing of roots in liquid MS medium with napthylacetic acid (1.5 microM) for P. nodiflora and indole butyric acid (3 microM) for L. reticulata afforded considerable increase in root mass. HPTLC profiles and microscopic examination of transverse sections of in vitro and naturally grown roots provided information on secondary metabolite accumulation vis-à-vis developmental stages of the root. 相似文献