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91.
Huang  Jiao  Li  Minhua  Li  Jinhong  Liang  Baoyun  Chen  Zhaoxia  Yang  Jialei  Guo  Xiaojing  Huang  Siyun  Gu  Lian  Su  Li 《Biochemical genetics》2021,59(6):1359-1380
Biochemical Genetics - Long non-coding RNAs (lncRNAs) have been reported to play an important role in cardiovascular diseases. The present study aimed to investigate the levels of lncRNA H19 in...  相似文献   
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93.
Growth rate and energy reserves are important determinants of fitness and are governed by endogenous and exogenous factors. Thus, examining the influence of individual and multiple stressors on growth and energy reserves can help estimate population health under current and future conditions. In young anadromous fishes, freshwater habitat quality determines physiological state and fitness of juveniles emigrating to marine habitats. In this study, the authors tested how temperature and food availability affect survival, growth and energy reserves in juvenile anadromous alewives (Alosa pseudoharengus), a forage fish distributed along the eastern North American continent. Field-collected juvenile anadromous A. pseudoharengus were exposed for 21 days to one of two temperatures (21°C and 25°C) and one of two levels of food rations (1% or 2% tank biomass daily) and compared for differences in final size, fat mass-at-length, lean mass-at-length and energy density. Increased temperature and reduced ration both led to lower growth rates, and the effect of reduced ration was greater at higher temperature. Fat mass-at-length decreased with dry mass, and energy density increased with total length, suggesting size-based endogenous influences on energy reserves. Lower ration also directly decreased fat mass-at-length, lean mass-at-length and energy density. Given the fitness implications of size and energy reserves, temperature and food availability should be considered important indicators of nursery habitat quality and incorporated in A. pseudoharengus life-history models to improve forecasting of population health under climate change.  相似文献   
94.
Chen  Jiakui  Li  Gaofei  Lian  Junwei  Ma  Ning  Huang  Zhibin  Li  Jianchao  Wen  Zilong  Zhang  Wenqing  Zhang  Yiyue 《中国科学:生命科学英文版》2021,64(12):2186-2201
Science China Life Sciences - Hematopoietic stem and progenitor cells (HSPCs) are able to self-renew and can give rise to all blood lineages throughout their lifetime, yet the mechanisms regulating...  相似文献   
95.

Background

A recessive mutation “c” in the Mexican axolotl, Ambystoma mexicanum, results in the failure of normal heart development. In homozygous recessive embryos, the hearts do not have organized myofibrils and fail to beat. In our previous studies, we identified a noncoding Myofibril-Inducing RNA (MIR) from axolotls which promotes myofibril formation and rescues heart development.

Results

We randomly cloned RNAs from fetal human heart. RNA from clone #291 promoted myofibril formation and induced heart development of mutant axolotls in organ culture. This RNA induced expression of cardiac markers in mutant hearts: tropomyosin, troponin and α-syntrophin. This cloned RNA matches in partial sequence alignment to human microRNA-499a and b, although it differs in length. We have concluded that this cloned RNA is unique in its length, but is still related to the microRNA-499 family. We have named this unique RNA, microRNA-499c. Thus, we will refer to this RNA derived from clone #291 as microRNA-499c throughout the rest of the paper.

Conclusions

This new form, microRNA-499c, plays an important role in cardiac development.  相似文献   
96.
Phytolacca americana L. can accumulate large amounts of heavy metals in its aerial tissues, especially cadmium (Cd) and manganese (Mn). It has great potential for use in phytoextraction of metals from multi-metal-contaminated soils. This study was conducted to further investigate the Cd- and Mn-tolerance strategies of this plant. Concentrations of non-protein thiols (NPTs) and phytochelatins (PCs) in leaves and roots increased significantly as the concentration of Cd in solution increased. The molar ratios of PCs:soluble Cd ranged from 1.8 to 3.6 in roots and 8.1 to 31.6 in leaves, suggesting that the cellular response involving PC synthesis was sufficient to complex Cd ions in the cytosol, especially that of leaves. In contrast, excess Mn treatments did not result in a significant increase in NPT or PC concentrations in leaves or roots. Oxalic acid concentrations in leaves of plants exposed to 2 or 20 mM Mn reached 69.4 to 89.3 mg (0.771 to 0.992 mmol) g–1 dry weight, respectively, which was approximately 3.7- to 8.6-fold higher than the Mn level in the 0.6 M HCl extract. Thus, oxalic acid may play an important role in the detoxification of Mn.  相似文献   
97.
The discovery of threosyl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) as a potent anti-HIV agent has led to the synthesis and biological evaluation of 5 ′-deoxyversions of threosyl phosphonate nucleosides from 1,4-dihydroxy-2-butene. The synthesized nucleoside phosphonic acid analogues 14 and 19 were tested for anti-HIV activity as well as cytotoxicity. The adenine analogue 14 exhibits moderate in vitro anti-HIV-1 activity (EC50 = 12.6 μM).  相似文献   
98.
Novel syntheses of 4′-modified cyclopentenyl pyrimidine C-nucleosides were performed via C-C bond formation using SN2 alkylation via the key intermediate mesylates 6 and 16, which were prepared from acyclic ketone derivatives. When antiviral evaluation of synthesized compound was performed against various viruses such as HIV-1, HSV-1 and HSV-2, isocytidine analogue 20 showed moderate anti-HIV activity in CEM cell line (EC50 = 13.1 μmol).7  相似文献   
99.
100.
Cardiomyocyte apoptosis is a common pathological alteration in heart disease which results in systolic dysfunction or sudden death. Klotho is a novel anti-aging hormone. We tested the effects of klotho on cell apoptosis in isoproterenol-treated cardiomyocytes. In BALB/c mice, cardiac injury was induced by subcutaneous injection of isoproterenol (5mg/kg, for 9days, sc). Klotho (0.01 mg/kg, every other day for 4days, ip) was administered to determine the changes in isoproterenol-induced apoptosis. Mouse heart was harvested at day 2, day 5, and day 9 after isoproterenol injection. Isoproterenol induced cardiac apoptosis and endoplasmic reticulum (ER) stress in a time-dependent manner. However, klotho partly reversed isoproterenol-induced cardiac apoptosis and ER stress. These same effects were observed in cultured cardiomyocytes. Furthermore, the results also showed that SB203580, a p38 inhibitor, and SP600125, a c-Jun NH2-terminal kinase (JNK) inhibitor, reduced cardiomyocyte apoptosis and ER stress, however, klotho suppressed isoproterenol-induced activation of p38 and JNK. Taken together, these results indicated that cardioprotection by klotho was related to the attenuation of ER stress and ER stress-induced apoptosis, at least partly, through suppressing activation of the p38 and JNK pathway.  相似文献   
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