Objective:To investigate the selenium levels in hair, grain, and soil samples collected from residents in typical Keshan disease (KD) endemic and non-endemic areas of Yunnan Province and Inner Mongolia Autonomous Region (referred to as Inner Mongolia), and to provide basic data for evaluating the effectiveness of KD prevention and control strategies.Methods:In 2018, one county with a history of severe KD and one non-endemic county with a similar environment were selected from each of Yunnan Province and Inner Mongolia. Within each county, one natural village was selected as the survey site. Ten soil samples were collected from each village. Ten households were stratified based on their annual per capita income levels of low, medium, and high (3, 4, 3 households, respectively). Three samples of hair and three samples of grain were collected from each household, and selenium level was measured using hydride atomic fluorescence spectrometry.Results:A total of 118 hair samples, 125 grain samples, and 39 soil samples were collected. The selenium levels in the hair of residents from KD endemic areas were significantly lower than those from non-endemic areas within the same province ( P < 0.05), and there was no statistically significant difference in selenium levels in grain and soil ( P > 0.05). The selenium level in the hair of residents in Yunnan Province [0.36 (0.31, 0.41) mg/kg] was higher than that in Inner Mongolia [0.31 (0.25, 0.35) mg/kg, Z = - 3.87, P < 0.001]. The proportion of sufficient hair selenium levels (≥0.30 mg/kg) was 86.7% (52/60) in Yunnan Province and 55.2% (32/58) in Inner Mongolia, with a statistically significant difference (χ 2 = 14.26, P < 0.001). Selenium levels in grain and soil in Yunnan Province were lower than those in Inner Mongolia ( P < 0.001). The proportion of sufficient grain selenium levels (> 0.02 mg/kg) was 5.7% (4/70) in Yunnan Province and 12.7% (7/55) in Inner Mongolia, with a significant difference (χ 2 = 11.88, P = 0.003). The selenium levels in soil in both provinces reached the sufficient level (≥0.20 mg/kg). Conclusions:The selenium levels in the population of KD endemic areas are lower than those in non-endemic regions, and the selenium deficiency among residents in Inner Mongolia is more prominent than in Yunnan Province. The selenium levels in Inner Mongolia's grain and soil are higher than those in Yunnan Province. In the future prevention and control of KD attention should be paid to monitoring the selenium nutrition level of the population in KD areas, especially in Inner Mongolia areas located in the north.

Objective:To investigate the selenium levels in hair, grain, and soil samples collected from residents in typical Keshan disease (KD) endemic and non-endemic areas of Yunnan Province and Inner Mongolia Autonomous Region (referred to as Inner Mongolia), and to provide basic data for evaluating the effectiveness of KD prevention and control strategies.Methods:In 2018, one county with a history of severe KD and one non-endemic county with a similar environment were selected from each of Yunnan Province and Inner Mongolia. Within each county, one natural village was selected as the survey site. Ten soil samples were collected from each village. Ten households were stratified based on their annual per capita income levels of low, medium, and high (3, 4, 3 households, respectively). Three samples of hair and three samples of grain were collected from each household, and selenium level was measured using hydride atomic fluorescence spectrometry.Results:A total of 118 hair samples, 125 grain samples, and 39 soil samples were collected. The selenium levels in the hair of residents from KD endemic areas were significantly lower than those from non-endemic areas within the same province ( P < 0.05), and there was no statistically significant difference in selenium levels in grain and soil ( P > 0.05). The selenium level in the hair of residents in Yunnan Province [0.36 (0.31, 0.41) mg/kg] was higher than that in Inner Mongolia [0.31 (0.25, 0.35) mg/kg, Z = - 3.87, P < 0.001]. The proportion of sufficient hair selenium levels (≥0.30 mg/kg) was 86.7% (52/60) in Yunnan Province and 55.2% (32/58) in Inner Mongolia, with a statistically significant difference (χ 2 = 14.26, P < 0.001). Selenium levels in grain and soil in Yunnan Province were lower than those in Inner Mongolia ( P < 0.001). The proportion of sufficient grain selenium levels (> 0.02 mg/kg) was 5.7% (4/70) in Yunnan Province and 12.7% (7/55) in Inner Mongolia, with a significant difference (χ 2 = 11.88, P = 0.003). The selenium levels in soil in both provinces reached the sufficient level (≥0.20 mg/kg). Conclusions:The selenium levels in the population of KD endemic areas are lower than those in non-endemic regions, and the selenium deficiency among residents in Inner Mongolia is more prominent than in Yunnan Province. The selenium levels in Inner Mongolia's grain and soil are higher than those in Yunnan Province. In the future prevention and control of KD attention should be paid to monitoring the selenium nutrition level of the population in KD areas, especially in Inner Mongolia areas located in the north.

According to the general goal of long term development of basic science from 2021 to 2035 and the "14th Five-Year Plan" in China, starting from the reasearch characteristics and the basic situation of endemiology, this study discusses the strategic position, development law, development trend, development status and layout, development goals and realization ways of endemiology, combined with the strategic needs of the discipline, the important interdisciplinary research areas of endemiology are put forward. The purpose of this study is to promote the rapid development of basic research on endemic diseases, to provide reference for the scientific and technological layout and policy formulation of the endemiology, to provide reference for the "14th Five-Year Plan" in China, and to provide guarantee for the people in the sick area to seek health.

Based on the general goal of the medium and long term development of basic science from 2021 to 2035 and the "14th Five-Year Plan" in China, combined with the national strategic needs, this paper discusses the five priority development areas of endemiology according to the development trends and characteristics of endemiology in the next 5 - 15 years. The five areas are study on the pathogenesis and prevention measures of endemic fluorosis; study on risk assessment, pathogenic mechanism and control strategy of environmental arsenic exposure; research on the basis and application transformation of the pathogenesis of iodine nutrition-related diseases; molecular mechanism and targeted intervention of cartilage injury in Kashin-Beck disease; precise prevention and treatment, preservation of biological samples and etiology study of Keshan disease. Combined with the scientific significance and national strategic needs of various field, the authors analyze its main study directions and core scientific issues.

Heart activity is highly dependent on adenosine triphosphate (ATP) produced via mitochondrial oxidative phosphorylation. Traditional therapeutics has developed drugs by repairing damaged mitochondrial DNA, reducing mitochondrial reactive oxygen species (ROS) production, and accelerating the degradation of damaged mitochondria and recycle. In recent years, however, mitochondrial replacement therapy has taken a different strategy, and has entered the clinical trial stage. This review will summarize the research progress of cardiovascular drugs targeting mitochondria and mitochondrial replacement therapy to provide a new perspective for addressing some relevant endemic diseases in China.

With the huge advances in rural China since 1980s,rampant Keshan disease (KD)has been fading away,and therefore we set an ultimate goal at overall elimination.In recent years,the evaluation results showed that there were still some obstacles in achieving this goal.By explaining the pathogenesis and epidemic mechanism of KD and the factors regulating the fluctuation of the disease,as a kind of local lifestyle disease induced by poverty,the author think,it will be of very low possibility in breaking out again thanks to the long-term exchange of cereal commodities and current poverty relief program.And the next move is to revise the existing criteria for KD elimination and to maintain the state of elimination primarily through health education and social economic improvement in all affected areas.

Objective To observe the intervention effect of vitamin C (Vit C) and adenosine triphosphate (ATP) on myocardial fibrosis in rats.Methods Forty male SD rats were selected,body weight were 125-140 g,and they were divided into 8 groups according to body weight using a random number table method.Four rats for control group,3 rats for model group,6 rats for Vit C early group,6 rats for ATP early group,6 rats for Vit C + ATP early group,5 rats for Vit C late group,5 rats for ATP late group,and 5 rats for Vit C + ATP late group.Rats in model group and these intervention groups were induced with doxorubicin (2 mg/kg each week) for 6 weeks,and control group was given the same amount of normal saline.All early groups were intragastrically administered with Vit C (200 mg·kg-1·d-1),ATP (45 mg·kg-1·d-1) and Vit C + ATP (200 mg·kg-1·d-1 + 45 mg·kg-1 ·d-1) in the fourth week;these late groups were intragastrically administered with the same dose in the sixth week;each group was continuously administered for 21 days.Three days after the last intervention,cardiac ultrasonography was performed in all surviving rats,and left ventricular end diastolic diameter (LVEDD),left ventricular end systolic diameter (LVESD),left ventricular ejection fraction (LVEF),and left ventricular fractional shortening (LVFS) were recorded.The rats were sacrificed and the hearts were taken.HE staining and Masson staining were used to observe the pathological changes of myocardial tissue and the collagen volume fraction (CVF) was calculate.Serum cardiac troponin Ⅰ (CTn-Ⅰ) and type Ⅰ procollagen amino terminal peptide (PINP) levels were determined by enzyme-linked immunosorbent assay (ELISA).Results Compared with control group [(3.65 ± 0.25) mm,(80.63 ± 3.03)％,(43.57 ± 2.54)％],LVESD [(5.07 ± 0.58),(4.06 ± 0.68),(4.71 ± 0.43),(4.87 ± 0.44),(4.79 ± 0.59),(5.07 ± 0.62),(4.97 ± 0.29) mm] of model group and each intervention groups were increased,LVEF [(62.17 ± 4.92)％,(71.28 ± 3.54)％,(65.03 ± 3.35)％,(59.81 ± 2.45)％,(60.42 ± 9.22)％,(60.15 ± 3.06)％,(60.65 ± 2.05)％],and LVFS [(30.05 ± 2.95)％,(36.44 ± 2.90)％,(31.63 ± 2.15)％,(26.95 ± 1.05)％,(28.35 ± 6.84)％,(27.79 ± 2.41)％,(28.38 ± 1.42)％] were decreased (P ＜ 0.05);compared with model group,LVESD was decreased,LVEF and LVFS were increased in Vit C early group (P ＜ 0.05).HE staining showed that the myocardial pathology of each early group improved to different degrees,such as cardiomyocyte degeneration,necrosis and fibrosis,inflammatory cell infiltration,moderate degree of interstitial edema,Vit C early group and Vit C + ATP early group were more pronounced.Masson staining showed significant improvement in fibrosis in the Vit C early group and Vit C + ATP early group,and collagen fibers were significantly reduced.Compared with the control group [(0.52 ± 0.14)％],the CVF [(27.11 ± 5.05)％,(9.80 ± 1.84)％,(16.55 ± 2.21)％,(5.06 ± 1.45)％,(12.11 ± 2.12)％,(15.71 ± 1.56)％,(16.93 ± 2.76)％] of myocardial tissue in model group and each intervention groups were significantly increased (P ＜ 0.05).There were no significant differences in CTn-Ⅰ and PINP levels between the eight groups (P ＞ 0.05).Conclusions Vit C can reduce myocardial fibrosis and improve cardiac function in the early stage.The effect of ATP alone to improve fibrosis is not obvious.

Heart failure is the leading cause of death in cardiovascular diseases.Despite effectiveness of current clinical treatment,it is not satisfactory in general,so more effective and optimal therapies are under seeking.All available evidences show that cardiac muscles have limited regenerative capacity in adult mammals,while some vertebrates,such as zebrafish and salamander,can completely recover through perfect regeneration following myocardial injury.In-depth investigation into underlying mechanism may facilitate the development of human heart's potential of scarless healing.In this review paper,we summarized recent progresses in distinct cardiac regenerative capacity and their main influencing factors of several model animals through comparative analysis.

Recent studies have overturned the previous belief that adult cardiocyte had been thought to permanently withdraw from cell-cycle activity.At present,targeting cardiocyte proliferation is one of current major therapeutic strategies for myocardial injury and repair following injury.Therefore,the author review the research progress in cell-cycle regulation of cardiocyte proliferation by systematically searched the relevant studies.