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921.
922.
Stobadine inhibits doxorubicin-induced apoptosis through a caspase-9 dependent pathway in P815 mastocytoma cells 总被引:3,自引:0,他引:3
Doxorubicin (DOXO), a widely used chemotherapeutic agent, induces apoptosis in transformed and non-transformed cells. The apoptotic effect of DOXO has been linked to the generation of reactive oxygen species (ROS). Antioxidants may be effective in the prevention of DOX-induced apoptosis. In the present study we investigated the effects of stobadine, a pyridoindole antioxidant in a DOXO-induced apoptosis model of P815 cells by flow cytometric analyses and by measuring caspase-3 and caspase-9 activities. Pretreating cells with stobadine significantly increased cell viability and decreased apoptosis rate. Inhibition in apoptosis was observed at maximum levels following treatment of cells with 10(-7)M stobadine as evident from flow cytometric analyses. The antiapoptotic effect of stobadine was further confirmed by inhibition of caspase-3 and caspase-9 activities. We found that the antioxidative effects of stobadine were comparable to the effects of a well known antioxidant, N-acetyl l-cysteine (NAC). 相似文献
923.
Riviere T Diedhiou AG Diabate M Senthilarasu G Natarajan K Verbeken A Buyck B Dreyfus B Bena G Ba AM 《Mycorrhiza》2007,17(5):415-428
Ectomycorrhizal (ECM) fungi have a worldwide distribution. However, the ecology of tropical ECM fungi is poorly documented,
limiting our understanding of the symbiotic associations between tropical plants and fungi. ECM Basidiomycete diversity was
investigated for the first time in two tropical rain forests in Africa (Western Upper Guinea) and in Asia (Western Ghats,
India), using a fragment of the mitochondrial large subunit rRNA gene to type 140 sporocarps and 54 ectomycorrhizas. To evaluate
taxonomic diversity, phylogenetic analyses were performed, and 40 sequences included from identified European specimens were
used as taxonomic benchmarks. Five clades were recovered corresponding to six taxonomic groups: boletoids, sclerodermatoids,
russuloids, thelephoroids, and a clade grouping the Amanitaceae and Tricholomataceae families. Our results revealed that the
Russulaceae species display a great diversity with several putative new species, especially in Guinea. Other taxonomic issues
at family/section levels are also briefly discussed. This study provides preliminary insights into taxonomic diversity, ECM
status, and biogeographic patterns of ECM fungi in tropical two rain forest ecosystems, which appear to be as diverse as in
temperate and boreal forests. 相似文献
924.
Lecain E Omri B Behar-Cohen F Tran Ba Huy P Crisanti P 《Apoptosis : an international journal on programmed cell death》2007,12(2):333-342
Aminoglycoside antibiotics are ototoxic, inducing irreversible sensorineural hearing loss mediated by oxidative and excitotoxic
stresses. The NF-κB pathway is involved in the response to aminoglycoside damage in the cochlea. However, the molecular mechanisms
of this ototoxicity remain unclear. We investigated the expression of PKCζ, a key regulator of NF-κB activation, in response
to aminoglycoside treatment. Amikacin induced PKCζ cleavage and nuclear translocation. These events were concomitant with
chromatin condensation and paralleled the decrease in NF-κB (p65) levels in the nucleus. Amikacin also induced the nuclear
translocation of apoptotic inducing factor (AIF). Prior treatment with aspirin prevented PKCζ cleavage and nuclear translocation.
Thus, aspirin counteracts the early effects of amikacin, thereby protecting hair cells and spiral ganglion neurons. These
results demonstrate that PKCζ acts as sentinel connecting specific survival pathways to mediate cellular responses to amikacin
ototoxicity.
E. Lecain and B. Omri both authors contributed equally. 相似文献
925.
926.
Pérez-Torres I El Hafidi M Infante O Baños G 《Canadian journal of physiology and pharmacology》2008,86(1-2):25-35
We studied the effect of varying levels of sex hormones, induced by ovariectomy and administration of testosterone or estradiol, on aortic reactivity in female rats with metabolic syndrome (MS) induced by a sucrose diet. Vasoreactivity of aortic rings, blood pressure, intra-abdominal fat, serum triglycerides, nitrates and nitrites, and TBARS were evaluated. Intact MS and ovariectomized MS had higher BP than intact control (C) and ovariectomized C, respectively; estradiol administration decreased BP in ovariectomized MS but not in ovariectomized C. Triglycerides and fat were both higher in MS. Triglycerides were not modified by surgery or hormone treatment, but ovariectomy increased fat. When ovariectomy was combined with hormones, however, fat was reduced to the level of intact rats. Ovariectomy decreased, but hormones increased, serum nitrates and nitrites. Vasoconstriction was larger in intact MS and ovariectomized MS + testosterone aortas than in intact C and ovariectomized C + testosterone, respectively. Vasodilation was reduced in intact MS and ovariectomized MS + testosterone compared with intact C, ovariectomized C + testosterone, ovariectomized MS, and ovariectomized MS + estradiol. The results suggest endothelial dysfunction in intact MS and ovariectomized MS + testosterone, but protection by ovariectomy + estradiol in MS due to hormones. Indomethacin reduced all contractions, but the effect was greater in estradiol-treated rats. L-NAME increased contractility, more in the ovariectomized C and MS groups and less in the estradiol-treated groups. 相似文献
927.
Tung Hoang Thanh Thuong Tran Thi Cuong Do Manh Luan Vu Quoc Hien Vu Thi Hieu Tran Nam Nguyen Ba Phuong Hoang Thi Nhu Van The Vinh Bui Khai Hoang Dac Nhut Duong Tan 《Plant Cell, Tissue and Organ Culture》2021,145(2):393-403
Plant Cell, Tissue and Organ Culture (PCTOC) - One of the common problems in strawberry (Fragaria?×?ananassa) micropropagation is the vitrification phenomenon (succulent plantlets,... 相似文献
928.
929.
Cluster Computing - Most traditional Public-Key Encryption with keyword Search (PEKS) schemes are suffering a tremendous threat occasioned by the burgeoning of quantum computing since these schemes... 相似文献
930.
Intra‐articular injection of autologous adipose‐derived mesenchymal stem cells in the treatment of knee osteoarthritis 下载免费PDF全文
Duško Spasovski Vesna Spasovski Zoran Baščarević Maja Stojiljković Miša Vreća Marina Anđelković Sonja Pavlović 《The journal of gene medicine》2018,20(1)