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Objective To investigate and analyze the level of homocysteine (Hcy) in Tibet and to analyze the differences of Hcy level in different altitude regions, genders and ages, and thus to provide the prevalence profile of hyperhomocysteine and the differences in relevant tests between HHcy(hyperhomocysteinemia) and non-HHcy populations. Methods Totally 1 615(male n=585) subjects were selected from Ngari, Lhasa, Shigatse and Nyingchi plateau areas of Tibet by stratified cluster sampling. Serum Hcy level was analyzed and the difference of Hcy level in populations located at different altitude plateau areas, gender groups were found. The prevalence of hyperhomocysteine and related test were analyzed. Kruskal Wallis test was used to compare Hcy levels in different altitudes, genders and age groups, and Pearson Chi-square test was used to compare HHcy prevalence. Variance analysis was used for the differences of different test indicators between non-HHcy and HHcy populations. Results The level of Hcy in different regions and different genders were statistically significant, which was higher in males than that in females, and higher in Lhasa and Shigatse than in Nyingchi and Ngari. There was difference in serum HHcy prevalence among different genders, regions and age groups. Males showed a higher level than females, people from Lhasa and Shigatse showed a higher level than those from Nyingchi and Ngari. Conclusions The incidence of hyperhomocysteinemia in Tibet is statistically significant in different areas, different genders and different age groups. So this study provides a scientific basis for the rational use of Hcy as an indicator in clinical practice of prevention and treatment of related diseases in plateau areas.

SignificanceDynamically understanding the microscopic processes governing ordering transformations has rarely been attained. The situation becomes even more challenging for nanoscale alloys, where the significantly increased surface-area-to-volume ratio not only opens up a variety of additional freedoms to initiate an ordering transformation but also allows for kinetic interplay between the surface and bulk due to their close proximity. We provide direct evidence of the microscopic processes controlling the ordering transformation through the surface-bulk interplay in Pt-Fe nanoalloys and new features rendered by variations in alloy composition and chemical stimuli. These results provide a mechanistic detail of ordering transformation phenomena which are widely relevant to nanoalloys as chemical ordering occurs in most multicomponent materials under suitable environmental bias.

This study explores the potential mechanisms of obstructive sleep apnoea (OSA) complicates type 2 diabetes mellitus (T2DM) by which chronic intermittent hypoxia (CIH) induces insulin resistance and cell apoptosis in the pancreas through oxidative stress. Four‐ and eight‐week CIH rat models were established, and Tempol (100 mg/kg/d), was used as an oxidative stress inhibitor. This study included five groups: 4‐week CIH, 4‐week CIH‐Tempol, 8‐week CIH, 8‐week CIH‐Tempol and normal control (NC) groups. Fasting blood glucose and insulin levels were measured in the serum. The expression levels of 8‐hidroxy‐2‐deoxyguanosine (8‐OHdG), tribbles homologue 3 (TRB3), c‐Jun N‐terminal kinase (JNK), phosphorylated JNK (p‐JNK), insulin receptor substrate‐1 (IRS‐1), phosphorylated IRS‐1 (Ser307) (p‐IRS‐1ser307), protein kinase B (AKT), phosphorylated AKT (Ser473) (p‐AKTser473), B cell lymphoma protein‐2 (Bcl‐2), cleaved‐caspase‐3 (Cl‐caspase‐3), and the islet cell apoptosis were detected in the pancreas. CIH induced oxidative stress in the pancreas. Compared with that in the NC group and CIH‐Tempol groups individually, the homeostasis model assessment of insulin resistance (HOMA‐IR) and apoptosis of islet cells was increased in the CIH groups. CIH‐induced oxidative stress increased the expression of p‐IRS‐1Ser307 and decreased the expression of p‐AKTSer473. The expression levels of TRB3 and p‐JNK were higher in the CIH groups than in both the CIH‐Tempol and NC groups. Meanwhile, the expressions of Cl‐caspase‐3 and Bcl‐2 were upregulated and downregulated, respectively, in the CIH groups. Hence, the present study demonstrated that CIH‐induced oxidative stress might not only induce insulin resistance but also islet cell apoptosis in the pancreas through TRB3 and p‐JNK. [ABSTRACT FROM AUTHOR]

As a life‐threatening disease, acute lung injury (ALI) may progress to chronic pulmonary fibrosis. For the treatment of lung injury, Tempol is a superoxide dismutase mimetic and intracellular redox agent that can be a potential drug. This study investigated the regulatory mechanism of Tempol in the treatment of ALI. A mouse model of ALI was established, and HE staining was used to examine histomorphology. The CCK‐8 assay was used to measure cell viability, and oxidative stress was assessed by corresponding kits. Flow cytometry and dichlorodihydrofluorescein diacetate staining assays were used to detect reactive oxygen species (ROS) levels. Protein expression levels were measured by Western blot analysis and ELISA. Pulmonary vascular permeability was used to measure the lung wet/dry weight ratio. The level of oxidative stress was increased in ALI mice, and the level of ferroptosis was upregulated. Tempol inhibited this effect and alleviated ALI. The administration of Tempol alleviated the pathological changes in ALI, inhibited pulmonary vascular permeability, and improved lung injury in ALI mice. The upregulation of genes essential for glutathione (GSH) metabolism induced by lipopolysaccharide (LPS) was inhibited by Tempol. In addition, nuclear factor‐related factor 2 (Nrf2) is activated by Tempol therapy to regulate the de novo synthesis pathway of GSH, thereby alleviating LPS‐induced lung epithelial cell damage. The results showed that Tempol alleviated ALI by activating the Nrf2 pathway to inhibit oxidative stress and ferroptosis in lung epithelial cells. In conclusion, this study demonstrates that Tempol alleviates ALI by inhibiting ferroptosis in lung epithelial cells through the effect of Nrf2 on GSH synthesis. [ABSTRACT FROM AUTHOR]

BACKGROUND: Against the background of global warming, heat stress has become more frequent, which adversely affects the growth and development of spring maize plants in Northeast China. To adapt the regional maize production to climate change, it is imperative to understand the spatio‐temporal characteristics of heat stress. In the present study, we analyzed three of the indices for heat stress, including the number of heat stress days, heating degree days (HDD, the total heat degree‐days during critical stages), and the percentage of stations with heat stress. RESULTS: From 1981 to 2019, the number of heat stress days varied greatly among the study years, ranging from 0 to 14 and 27 days, respectively. The average HDD was 7.8 and 5.0 °C day from 1981 to 2000, respectively, and the main hot‐spots of heat stress occurred in the southwest regions. Moreover, compared with 1981–2000, the region of HDD during anthesis higher than 10 °C day in 2041–2060 under the SSP1‐2.6 and SSP5‐8.5 climate scenarios increased by 9.1–50.1% and 0.1–28.6%. The average HDD during the critical stages from 2041 to 2060 increased under the SSP5‐8.5 climate scenario, being 1.5 times higher than that during 1981‐2000. HDD during maize anthesis and the grain‐filling period showed an overall increasing trend with years. About 19% and 58% of the study locations showed heat stress during the past 39 years, respectively. CONCLUSION: Heat stress during anthesis and the grain‐filling period for spring maize in Northeast China is projected to increase toward the mid‐21st century. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]