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211.
人心肌肌球蛋白轻链1的克隆,表达纯化和单抗制备   总被引:2,自引:2,他引:2  
报道了中国人心肌肌球蛋白轻链1cDNA的核苷酸序列,并由此推算的氨基酸序列。与国外发表的人心肌肌球蛋白轻链的氨基酸序列比较,发现有两处差异,即在24位,由谷氨酸变为丙氨酸,则从98位起至101位有4个氨基酸序列的连续差异,即由天冬酰胺-精氨酸-丝氨酸-赖氨酸变为赖氨酸-脯氨酸-精氨酸-谷氨酰妥,推测可能是由于人种差异而引起的。利用该cDNA在大肠杆菌内的表达产物,已获得一株高效的抗中国人心肌肌球蛋  相似文献   
212.
Aging process in mammals is associated with a decline in amplitude and a long period of circadian behaviors which are regulated by a central circadian regulator in the suprachiasmatic nucleus (SCN) and local oscillators in peripheral tissues. It is unclear whether enhancing clock function can retard aging. Using fibroblasts expressing per2::lucSV and senescent cells, we revealed cycloastragenol (CAG), a natural aglycone derivative from astragaloside IV, as a clock amplitude enhancing small molecule. CAG could activate telomerase to antiaging, but no reports focused on its effects on circadian rhythm disorders in aging mice. Here we analyze the potential effects of CAG on d -galactose-induced aging mice on the circadian behavior and expression of clock genes. For this purpose, CAG (20 mg/kg orally), was administered daily to d -galactose (150 mg/kg, subcutaneous) mice model of aging for 6 weeks. An actogram analysis of free-running activity of these mice showed that CAG significantly enhances the locomotor activity. We further found that CAG increase expressions of per2 and bmal1 genes in liver and kidney of aging mouse. Furthermore, CAG enhanced clock protein BMAL1 and PER2 levels in aging mouse liver and SCN. Our results indicated that the CAG could restore the behavior of circadian rhythm in aging mice induced by d -galactose. These data of present study suggested that CAG could be used as a novel therapeutic strategy for the treatment of age-related circadian rhythm disruption.  相似文献   
213.
214.
Heat shock protein A12B (HSPA12B) is the newest member of a recently defined subfamily of proteins distantly related to the 70-kDa family of heat shock proteins (HSP70) family. HSP70s play a crucial role in protecting cells, tissues, organs and animals from various noxious conditions. Here we studied the dynamic expression changes and localization of HSPA12B after middle cerebral artery occlusion (MCAO) with reperfusion induced ischemic insult processes in adult rats. Apoptosis, as indicated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, was also increased in the peri-ischemic cortex compared to non-ischemic hemisphere. The expression of HSPA12B was strongly induced in the ischemic hemisphere of MCAO reperfusion rats in vivo. In vitro studies indicated that the up-regulation of HSPA12B may be involved in oxygen-glucose deprivation-induced PC12 cell death. And knockdown of HSPA12B in cultured differentiated PC12 cells by siRNA showed that HSPA12B inhibited the expression of active caspase-3. Collectively, these results suggested that HSPA12B may be required for protecting neurons from ischemic insults.  相似文献   
215.
Liu  Xi  Ding  Li  Yuan  Jing  Liao  Jian  Duan  Lian  Wang  Wenfei  Tan  Weiguo  Yu  Weiye  Zhou  Boping  Chen  Xinchun  Yang  Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to  相似文献   
216.

Background

The HIV-epidemic among MSM in China has worsened. In this key population, prevalence of HSV-2 and syphilis infection and co-infection with HIV is high.

Methods

A longitudinal study was conducted (n = 962) in Beijing, China, with three overlapping cohorts (n = 857, 757 and 760) consisting of MSM that were free from pairs of infections of concern (i.e. HIV-HSV-2, HIV-syphilis, HSV-2-syphilis) at baseline to estimate incidence of HIV, HSV-2, syphilis, and those of co-infection.

Results

The incidence of HIV, HSV-2 and syphilis in the overall cohort was 3.90 (95% CI = 2.37, 5.43), 7.87 (95% CI = 5.74, 10.00) and 6.06 (95% CI = 4.18, 7.94) cases per 100 person-years (PYs), respectively. The incidence of HIV-HSV-2, HIV-Syphilis and HSV-2-Syphilis co-infections was 0.30 (95% CI = 0.29, 0.88), 1.02 (95% CI = 0.13, 2.17) and 1.41 (95% CI: 0.04, 2.78) cases per 100 PYs, respectively, in the three sub-cohorts constructed for this study.

Conclusions

The incidence of HIV, HSV-2 and syphilis was very high and those of their co-infections were relatively high. Such co-infections have negative impacts on the HIV/STI epidemics. Prevention practices need to take such co-infections into account.  相似文献   
217.
218.

Aim

The aim of this study was to investigate the prevalence of interankle systolic blood pressure difference (sIAND) and its influencing factors in community population.

Methods

This study included 2849 (65.1±9.4 y) subjects. Blood pressure (BPs) of four limbs was simultaneously measured with 4 electronic sphygmomanometers after 10 min rest in supine position. The difference of systolic BP (SBP) between two ankles was calculated as DETASBP. The criterion for abnormal sIAND was ≥10 mmHg of absolute DeltaSBP, in which the criterion for 1o sIAND was 10–19 mmHg and for 2o sIAND was ≥20 mmHg. Age, gender, smoking, hypertension, family histories of hypertension and diabetes were recorded. Fasting blood glucose and lipids, circumference of hip and waist, and body mass index (BMI) were measured.

Results

The SBP was higher in the right ankle than in the left ankle (158.9±21.8 vs 157.3±21.6 mmHg, P<0.05) and mean DeltaSBP was 6.08±6.26 mmHg. Similar difference was found in both genders. The prevalence of abnormal was 18.5%, in which, the prevalence 1o sIAND was 15.3% and that of 2o sIAND was 3.1%. Multivariate regression analysis showed that age, waist circumference and blood glucose level were the positive factors for DeltaSBP. The normal upper limit for DeltaSBP was 16.7 mmHg in this population, the prevalence of sIAND by≥16 mmHg was 5.8%.

Conclusion

Aging, hypertension, obesity and abnormal glucose metabolism are positive factors for inter-ankle SBP difference.  相似文献   
219.
In this study, we aimed to study the role of growth factor receptor-bound protein 2 (Grb2) in palmitic acid-induced steatosis and other “fatty liver” symptoms in vitro. HepG2 cells, with or without stably suppressed Grb2 expression, were incubated with palmitic acid for 24 h to induce typical clinical “fatty liver” features, including steatosis, impaired glucose metabolism, oxidative stress, and apoptosis. MTT and Oil Red O assays were applied to test cell viability and fat deposition, respectively. Glucose uptake assay was used to evaluate the glucose utilization of cells. Quantitative polymerase chain reaction and Western blot were used to measure expressional changes of key markers of insulin signaling, lipid/glucose metabolism, oxidative stress, and apoptosis. After 24-h palmitic acid induction, increased fat accumulation, reduced glucose uptake, impaired insulin signaling, enhanced oxidative stress, and increased apoptosis were observed in HepG2 cells. Suppression of Grb2 in HepG2 significantly reduced fat accumulation, improved glucose metabolism, ameliorated oxidative stress, and restored the activity of insulin receptor substrate-1/Akt and MEK/ERK pathways. In addition, Grb2 deficiency attenuated hepatic apoptosis shown by reduced activation of caspase-3 and fluorescent staining. Modulation of Bcl-2 and Bak1 also contributed to reduced apoptosis. In conclusion, suppression of Grb2 expression in HepG2 cells improved hepatic steatosis, glucose metabolism, oxidative stress, and apoptosis induced by palmitic acid incubation partly though modulating the insulin signaling pathway.  相似文献   
220.
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