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971.
Journal of Evolutionary Biochemistry and Physiology - Among the available nanoparticles, those based on iron oxide are of particular interest due to their biological safety, magnetic properties,...  相似文献   
972.
Ptk2b has been found playing critical roles in oocyte maturation and subsequent fertilization in vitro. But what is the exact in vivo function in reproduction still elusive. Here, by constructing Ptk2b mutant mice, we found Ptk2b was not essential for mice fertility, unexpectedly, contrary to previously reported in vitro findings, we found Ptk2b ablation significantly improved female fecundity. Follicle counting indicated that the number of primordial follicles and growing follicles in matured mice was significantly increased in the absence of Ptk2b, whereas the primordial follicle formation showed no defects. We also found this regulation was in an autophosphorylation independent pathway, as autophosphorylation site mutant mice (PTK2BY402F) show no phenotype in female fertility. Further biochemistry studies revealed that Ptk2b ablation promotes folliculogenesis via Erk pathway mediate follicle survival. Together, we found a novel biological function of Ptk2b in folliculogenesis, which could be potentially used as a therapeutic target for corresponding infertility.  相似文献   
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Microbiology - Comparative study of methanogen diversity and potential activity of different methanogenic pathways in the sediments of young thermokarst and mature polygenetic Yamal lakes was...  相似文献   
976.
Microbiology - An Erratum to this paper has been published: https://doi.org/10.1134/S0026261721110011  相似文献   
977.
Microbiology - The taxonomic diversity and metabolic activity of microbial communities in the Laptev Sea water column above and outside the methane seep field were studied. The concentrations of...  相似文献   
978.
Microbiology - The technology of single-cell protein production from natural gas is based on using thermotolerant methanotrophic bacteria with high growth rates on methane. So far, the spectrum of...  相似文献   
979.
Molecular Biology - Molecular profiling of tumors may provide promising options for personalized treatment. We have examined the spectrum of germline and somatic mutations in 23 breast cancers (BC)...  相似文献   
980.
Tang  Ying  Li  Yingqin  Yu  Guangyin  Ling  Zemin  Zhong  Ke  Zilundu  Prince L. M.  Li  Wenfu  Fu  Rao  Zhou  Li-Hua 《Cellular and molecular neurobiology》2021,41(6):1373-1387

The imbalance between excess reactive oxygen species (ROS) generation and insufficient antioxidant defenses contribute to a range of neurodegenerative diseases. High ROS levels damage cellular macromolecules such as DNA, proteins and lipids, leading to neuron vulnerability and eventual death. However, the underlying molecular mechanism of the ROS regulation is not fully elucidated. Recently, an increasing number of studies suggest that microRNAs (miRNAs) emerge as the targets in regulating oxidative stress. We recently reported the neuroprotective effect of miR-137-3p for brachial plexus avulsion-induced motoneuron death. The present study is sought to investigate whether miR-137-3p also could protect PC12 cells against hydrogen peroxide (H2O2) induced neurotoxicity. By using cell viability assay, ROS assay, gene and protein expression assay, we found that PC-12 cells exposed to H2O2 exhibited decreased cell viability, increased expression levels of calpain-2 and neuronal nitric oxide synthase (nNOS), whereas a decreased miR-137-3p expression. Importantly, restoring the miR-137-3p levels in H2O2 exposure robustly inhibited the elevated nNOS, calpain-2 and ROS expression levels, which subsequently improved the cell viability. Furthermore, the suppressive effect of miR-137-3p on the elevated ROS level under oxidative stress was considerably blunted when we mutated the binding site of calpain-2 targted by miR-137-3p, suggesting the critical role of calpain-2 involving the neuroprotective effect of miR-137-3p. Collectively, these findings highlight the neuroprotective role of miR-137-3p through down-regulating calpain and NOS activity, suggesting its potential role for combating oxidative stress insults in the neurodegenerative diseases.

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