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41.
Rohollah Nikooie Sohil Jafari-Sardoie Vahid Sheibani Amir Nejadvaziri Chatroudi 《Journal of cellular physiology》2020,235(7-8):5649-5665
The TGF-β1-Smad pathway is a well-known negative regulator of muscle growth; however, its potential role in resistance training-induced muscle hypertrophy is not clear. The present study proposed to determine whether and how this pathway may be involved in resistance training-induced muscle hypertrophy. Skeletal muscle samples were collected from the control, trained (RT), control + SB431542 (CITGF), and trained + SB431542 (RTITGF) animals following 3, 5, and 8 weeks of resistance training. Inhibition of the TGF-β1-Smad pathway by SB431542 augmented muscle satellite cells activation, upregulated Akt/mTOR/S6K1 pathway, and attenuated FOXO1 and FOXO3a expression in the CITGF group (all p < .01), thereby causing significant muscle hypertrophy in animals from the CITGF. Resistance training significantly decreased muscle TGF-β1 expression and Smad3 (P-Smad3S423/425) phosphorylation at COOH-terminal residues, augmented Smad2 (P-Smad2-LS245/250/255) and Smad3 (P-Smad3-LSer208) phosphorylation levels at linker sites (all p < .01), and led to a muscle hypertrophy which was unaffected by SB431542, suggesting that the TGF-β1-Smad signaling pathway is involved in resistance training-induced muscle hypertrophy. The effects of inhibiting the TGF-β1-Smad signaling pathway were not additive to the resistance training effects on FOXO1 and FOXO3a expression, muscle satellite cells activation, and the Akt/mTOR/S6K1 pathway. Resistance training effect of satellite cell differentiation was independent of the TGF-β1-Smad signaling pathway. These results suggested that the effect of the TGF-β1-Smad signaling pathway on resistance training-induced muscle hypertrophy can be attributed mainly to its diminished inhibitory effects on satellite cell activation and protein synthesis. Suppressed P-Smad3S423/425 and enhanced P-Smad2-LS245/250/255 and P-Smad3-LSer208 are the molecular mechanisms that link the TGF-β1-Smad signaling pathway to resistance training-induced muscle hypertrophy. 相似文献
42.
Somayeh Najafi Dorcheh Soheila Rahgozar Daryush Talei 《Journal of cellular and molecular medicine》2021,25(13):6148-6160
Combination therapies, using medicinal herbs, are broadly recommended to attenuate the chemotherapy adverse effects. Based on our previous findings considering the anti-leukaemic effects of ginger extract on acute lymphoblastic leukaemia (ALL) cells, the present study was aimed to investigate the anti-cancer role of this pharmaceutical plant on ALL mice models. Moreover, we worked towards identifying the most anti-leukaemic derivative of ginger and the mechanism through which it may exert its cytotoxic impact. In vivo experiments were performed using five groups of six C57BL/6 nude mice, and the anti-leukaemic activity of ginger extract alone or in combination with methotrexate (MTX) was examined. Results showed increased survival rate and reduced damages in mice brain and liver tissues. Subsequently, MTT assay demonstrated synergistic growth inhibitory effect of 6-shogaol (6Sh) and MTX on ALL cell lines and patients primary cells. Eventually, the molecular anti-neoplastic mechanism of 6Sh was evaluated using Bioinformatics. Flow cytometry illustrated 6Sh-mediated apoptosis in Nalm-6 cells confirmed by Western blotting and RT-PCR assays. Further analyses exhibited the generation of reactive oxygen species (ROS) through 6Sh. The current study revealed the in vivo novel anti-leukaemic role of ginger extract, promoted by MTX. Moreover, 6-shogaol was introduced as the major player of ginger cytotoxicity through inducing p53 activity and ROS generation. 相似文献
43.
Bacillus sp. YX-1 glucose dehydrogenase (BsGDH) with good solvent resistance catalyzes the oxidation of β-d-glucose to d-glucono-1,5-lactone. Xylose is a recyclable resource from hemicellulase hydrolysis. In this work, to improve the preference of BsGDH for xylose, we designed seven mutants inside or adjacent to the substrate binding pocket using site-directed mutagenesis. Among all mutants, Ala258Phe mutant displayed the highest activity of 7.59 U mg−1 and nearly 8-folds higher kcat/Km value towards xylose than wild-type BsGDH. The kinetic constants indicated that the A258F mutation effectively altered the transition state. By analysis of modeled protein structure, Ala258Phe created a space to facilitate the reactivity towards xylose. A258F mutant retained good solvent resistance in glycol, ethyl caprylate, octane, decane, cyclohexane, nonane, etc. as with BsGDH. This work provides a protein engineering approach to modify the substrate stereo-preference of alcohol dehydrogenase and a promising enzyme for cofactor regeneration in chiral catalysis. 相似文献
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Genetic studies were carried out on seedling and agronomic characters amongst 50 sesame genotypes to estimate the genetic variation, determine the relationships amongst the characters and identify rapidly growing genotypes with vigorous seedling growth. The contribution of genetic variance was highest for the two mature characters, days to first flower (95.6%) and number of nodes to first flower (95.2%), and was medium/high (50–75%) for most of the seedling characters. Strong positive genetic correlations were obtained between various cotyledon and early leaf characteristics measured at 20 days after sowing. Based on these results several genotypes were identified as having rapid seedling growth and these could form an initial gene pool to provide material for screening for tolerance to sesame flea beetle. 相似文献
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Raphael Chijioke Njoku 《Dialectical Anthropology》2007,31(1-3):45-64
It is difficult to completely understand the life history of an intellectual excluding an understanding of his family upbringing
and formative years. Family upbringing and childhood environment, often the less known part of a life history, play crucial
roles in shaping the ideas and values individuals espouse in their adult life. Notwithstanding, this paper is not concerned
with Don C. Ohadike’s childhood. It rather focuses on the professional career of our able historian – that is the part of
his life as revealed by his most outstanding published writings. Ohadike’s published works contain a wellspring of idioms
that tell much about his values, quality of mind, and his mission as an African historian. Ohadike was a humanist, an African
patriot, and a nationalist crusader. His entire philosophy centered on safeguarding his African identity in an emergent world
of cultural imperialism.
The funds for this research were provided by a NEH-funded fellowship at the Schomburg Center, New York in the Spring of 2007.
I owe a lot of gratitude to Professor John McLeod and Dean Blaine Hudson for granting me the extra incentives to pursue my
research in New York. While all errors and misinterpretations are mine, I wish to thank the editors and anonymous reviewers
for Journal of Dialectical Anthropology for their perspective comments and suggestions on earlier drafts of this paper. 相似文献