Prevalence of hypertension in endemic and non-endemic areas of Keshan disease: A cross-sectional study in rural areas of China.

Background: Hypertension is a major public health concern that strongly influences the quality of life of people worldwide. Keshan disease (KD) is an endemic cardiomyopathy related to low selenium, threatening residents in rural areas of 16 provinces in China. Furthermore, the prevalence of hypertension in the KD-endemic areas has been increasing annually. However, hypertension research associated with KD has only focused on endemic regions, and no studies have compared hypertension prevalence between endemic and non-endemic areas. Therefore, this study investigated the prevalence of hypertension to provide a basis for preventing and controlling hypertension in the KD-endemic areas, even in rural areas. Methods: We extracted blood pressure information from cardiomyopathy investigation data from a cross-sectional study of the KD-endemic and non-endemic areas. The hypertension prevalence between the two groups was compared using the Chi-square test or Fisher s exact test. Additionally, Pearson's correlation coefficient was employed to evaluate the relationship between the per capita gross domestic product (GDP) and hypertension prevalence. Results: There was a statistically significant increase of hypertension prevalence in the KD-endemic areas (22.79%, 95% confidence interval [CI]: 22.30-23.27%) over the non-endemic areas (21.55%, 95% CI: 21.09-22.02%). In the KD-endemic areas, more men had hypertension than women (23.90% vs. 21.65%, P < 0.001). Furthermore, the hypertension prevalence was higher in the north than in the south in the KD-endemic areas (27.52% vs. 18.76%, P < 0.001), non-endemic areas (24.86% vs. 18.66%, P < 0.001), and overall (26.17% vs. 18.68%, P < 0.001). Finally, the prevalence of hypertension positively correlated with per capita GDP at province level. Conclusions: The increasing hypertension prevalence is a public health problem in the KD-endemic areas. Healthy diets, such as high consumption of vegetables and seafoods, and foods that are rich in selenium, might help prevent and control hypertension in the KD-endemic areas and other rural areas in China.

Mortality in Four Waves of COVID-19 Is Differently Associated with Healthcare Capacities Affected by Economic Disparities.

BACKGROUND: The greatest challenges are imposed on the overall capacity of disease management when the cases reach the maximum in each wave of the pandemic. METHODS: The cases and deaths for the four waves of COVID-19 in 119 countries and regions (CRs) were collected. We compared the mortality across CRs where populations experience different economic and healthcare disparities. FINDINGS: Among 119 CRs, 117, 112, 111, and 55 have experienced 1, 2, 3, and 4 waves of COVID-19 disease, respectively. The average mortality rates at the disease turning point were 0.036, 0.019. 0.017, and 0.015 for the waves 1, 2, 3, and 4, respectively. Among 49 potential factors, income level, gross national income (GNI) per capita, and school enrollment are positively correlated with the mortality rates in the first wave, but negatively correlated with the rates of the rest of the waves. Their values for the first wave are 0.253, 0.346 and 0.385, respectively. The r value for waves 2, 3, and 4 are -0.310, -0.293, -0.234; -0.263, -0.284, -0.282; and -0.330, -0.394, -0.048, respectively. In high-income CRs, the mortality rates in waves 2 and 3 were 29% and 28% of that in wave 1; while in upper-middle-income CRs, the rates for waves 2 and 3 were 76% and 79% of that in wave 1. The rates in waves 2 and 3 for lower-middle-income countries were 88% and 89% of that in wave 1, and for low-income countries were 135% and 135%. Furthermore, comparison among the largest case numbers through all waves indicated that the mortalities in upper- and lower-middle-income countries is 65% more than that of the high-income countries. INTERPRETATION: Conclusions from the first wave of the COVID-19 pandemic do not apply to the following waves. The clinical outcomes in developing countries become worse along with the expansion of the pandemic.

Association of selenium levels with the prevention and control of Keshan disease: A cross-sectional study.

PURPOSE: The prevalence of Keshan disease (KD) is low and has reached controlled or eliminated levels even in counties that had a high KD prevalence in the past. Few nationwide surveys on selenium levels in KD areas have been conducted in the past 2 decades. We conducted a cross-sectional study to investigate the selenium levels and their association with KD control and prevention in areas where KD is prevalent. METHODS: We collected 2143 human-hair, 698 soil, 701 rice, 607 flour, 521 corn, and 330 other-food samples from 49 counties with KD and 19 non-KD counties of nine KD provinces of China. The selenium content of samples was examined with hydride generation atomic fluorescence spectrometry. The difference in selenium levels between the KD and non-KD areas was analyzed. Cochran-Armitage trend tests were used to evaluate the association between selenium levels and KD control. RESULTS: The selenium levels in human hair, soil, staple foods, and other foods in the KD areas (0.2996 mg/kg, 0.1380 mg/kg, 0.0190 mg/kg and 0.0076 mg/kg, respectively) were lower than those in the non-KD areas (0.3700 mg/kg, 0.1930 mg/kg, 0.0240 mg/kg and 0.0165 mg/kg, respectively). The Cochran-Armitage tests showed that there was a trend for the selenium standard ratio in the counties to increase in the order of KD uncontrolled, to controlled, to eliminated (Z = 2.229, P < 0.05). CONCLUSION: The residents in the KD areas were found to be selenium-deficient. Improving the supply of staple foods containing selenium levels exceeding 0.025 mg/kg and abundant foodstuffs might contribute to KD control and prevention.

Gene network of a phosphoglycerate mutase in muscle wasting in mice.

We previously identified the insertion of an intracisternal A-particle retrotransposons (IAPs) sequence in a gene, 9630033F20Rik, that contains domains involved in glycolysis from a mouse model called lethal wasting (lew). However, because both IAP insertion and the muation of vesicle-associated membrane protein 1 (VAMP1) were discovered from lew, the impact of the IAP insertion and Vamp1 on the lew mouse phenotype needs further investigation. In this study, the effect of the 9630033F20Rik and Vamp1 on glycolysis and muscle-wasting genes in heart, muscle, and brain tissues was further investigated using data of gene expression profiles in these tissues. Our data indicated that the expression levels of 9630033F20Rik and Vamp1 are not associated with each other. While 9630033F20Rik affects the expression of several key genes in pathways of glycolysis and muscle wasting, Vamp1 affects a different set of genes, with fewer numbers. In situ hybridization indicated that the expression of 9630033F20Rik is different in musculoskeletal tissues between the muscle-wasting mouse model and the wild-type model. Our data indicated that 9630033F20Rik may play an important role in muscle wasting and that it has a distinguished characterization of gene network. Our data also suggest that both 9630033F20Rik and Vamp1 play functional roles in muscle development and lead to the muscle-wasting phenotype when they are mutated.

Comparison of LAIR-1 genetic pathways in murine vs human internal organs.

Growing evidence suggests that defective expression or dysfunction of LAIR-1, a novel immunoinhibitory receptor for collagen, is closely associated with some autoimmune diseases, cancers, as well as viral infections. We analyzed the variation of LAIR-1 genetic pathways in murine versus human internal organs, including the lung and brain. The results showed that, under physiological conditions, LAIR-1 links more closely to the common genes in mouse than in human, which poses tissue specificity. It means that mice experimental data in relation to the role of LAIR-1 immune regulation may be overestimated when applied to assess human conditions. Moreover, we found that the in vivo interaction of LAIR-1 with LAIR-2 rarely occurs, implying that the species difference in LAIR-1 genetic pathways could not be primarily attributed to the existence of human LAIR-2. In summary, this study opens the door for insight into LAIR-1 functions inside the human body, and raises concern as to extrapolative credibility of the murine model in biomedical research.

Suboptimal selenium supply--a continuing problem in Keshan disease areas in Heilongjiang province.

This study explores whether the declining prevalence of Keshan disease is associated with increasing selenium levels in Keshan disease areas in Heilongjiang province. Six counties endemic with Keshan disease and three non-endemic counties were selected as study areas. In each county, two townships and in each township one village were chosen in which to survey ten families about head hair, grain, and soil samples and to obtain demographic information. Selenium was measured with hydride generation-atomic fluorescence spectrometry. In each county endemic with Keshan disease, one of the villages was chosen to investigate the prevalence of the disease. We collected 534 head hair samples, 446 staple food samples, and 180 soil samples. The selenium levels of head hair and corn in the endemic counties were significantly lower than those in non-endemic counties. Family demographic information was homologous except for the composition of staple food. More residents in Keshan disease areas preferred flour and corn. The detection rate for latent Keshan disease had a significantly negative correlation with the corn selenium level in six counties endemic with Keshan disease. As the population in this region is still at risk for Keshan disease, selenium surveillance measures should be intensified.

Chronic exposure to cereal mycotoxin likely citreoviridin may be a trigger for Keshan disease mainly through oxidative stress mechanism.

The origin of Keshan disease (KD), an endemic cardiomyopathy particularly affected children and young women in China, has been a controversial and difficult problem in academics over the past decades. We hypothesize that mycotoxins likely citreoviridin may initiate KD mainly through oxidative stress mechanism by long-term consumption of mouldy cereals due to food shortage lifestyle. Dietary deficiency of selenium, proteins, Vitamin C, E, etc., may act as enhancing factors to exacerbate the pathological damage. This speculation can perfectly explain the features of KD and has received strong supporting evidences. If the hypothesis were to be confirmed, it is of very important value in monitoring and blocking the incidence of KD. Thus, future efforts are needed to investigate specific biomarkers of exposure to citreoviridin in KD cases.

[A study on the variation of goiter rates, urinary iodine and household salt iodine intake among children in West China].

OBJECTIVE: To study the factors leading to the variation of children's total goiter rates, urine iodine and salt iodine in West China. METHODS: Design effect (DEFF) was used to evaluate the variation of indicators. RESULTS: DEFF of children's total goiter rate was about 3.0 in 9 provinces, and the proportion was 75.0%. The DEFF of urine iodine was 1.0 - 3.5 in 6 provinces, and the proportion was 50.0%. The DEFF of intake rate of qualified iodized salt was over 3.0 in 11 provinces. The DEFF of covering rate of iodized salt was about 3.0 in 4 provinces. CONCLUSION: In order to provide scientific basis for IDD surveillance in China, other than bias due to methods of no-sampling, sample size should be further calculated in West China. Thus the main influencing factors of indicator variation could be measured with scientific and reasonable basis.