Effect of Flavonoids in Hawthorn and Vitamin C Prevents Hypertension in Rats Induced by Heat Exposure.

BACKGROUND: Excessive oxidative stress is associated with hypertension in professional high-temperature working conditions. Polyphenols exhibit a cardioprotective effect. Hawthorn contains high amounts of flavonoids, though its effect on hypertension protection has yet to be studied. This study aims to investigate this effect of extract of hawthorn (EH) or its combination with vitamin C (Vit. C) in rats induced by working under a hot environment. METHODS: Forty-two male rats were randomly divided into a control group under normal temperature and six treatment groups exposed at 33 ± 1 °C along with 1 h of daily treadmill running. They were orally provided with water, Vit. C (14mg/kg), EH (125, 250, and 500 mg/kg), and EH500 + Vit. C, once a day for four weeks. RESULTS: Both EH and Vit. C alone reduced the systolic and diastolic blood pressure of rats exposed to the heat environment; however, their joint supplementation completely maintained their blood pressure to the normal level throughout the experimental period. No morphological changes were found on the intima of aorta. Moreover, the co-supplementation of EH and Vit. C prevented the changes of heat exposure in inducing oxidative stress markers, such as glutathione peroxidase, catalase, total antioxidant capacity, and nitric oxide; the synergistic action was more effective than either individual treatment of EH and Vit. C. Furthermore, the administration of EH had more potent effects on increasing superoxide dismutase, IL-2, the 70 kilodalton heat shock proteins and high sensitivity C reactive protein, and decreasing serum malondialdehyde and lipofuscin in vascular tissue than those in Vit. C group. CONCLUSIONS: A strong synergistic effect of EH and Vit. C on the prevention of hypertension under heat exposure was established, as they inhibited the oxidative stress state. This study also sets up a novel intervention strategy in animal models for investigation on the early phases of hypertension induced by heat exposure.

High Physical Activity is Associated with an Improved Lipid Profile and Resting Heart Rate among Healthy Middle-aged Chinese People.

OBJECTIVE: To investigate the effects of physical activity (PA) on dyslipidemia and elevated resting heart rate (RHR) in a large-scale cross-sectional study in China. METHODS: We recruited community-based individuals who were 40-60 years old using a cluster sampling method. The PA levels of the participants were classified as low, moderate, or high, using the International Physical Activity Questionnaire. Dyslipidemia was defined as the detection of abnormalities in lipid indicators, and 4 lipid parameters were evaluated using fasting blood samples. Multivariate logistic regression analyses were used to evaluate the associations of PA with dyslipidemia and RHR. RESULTS: A total of 10,321 participants (38.88% men) were included in this study. The percentages of individuals with high, moderate, and low PA levels were 46.5%, 43.9%, and 9.6%, respectively. In both men and women, high PA provided odds ratios of 0.88 [95% confidence interval (CI): 0.83, 0.94] for dyslipidemia and 0.82 (95% CI: 0.73, 0.92) for elevated RHR, compared to participants with low PA. CONCLUSION: Our data suggested that substantial health benefits (related to dyslipidemia and elevated RHR) occurred at higher intensity PA, with greater energy consumption, in middle-aged Chinese people, and particularly in men.

Association of TNF-alpha-238G/A and 308 G/A gene polymorphisms with pulmonary tuberculosis among patients with coal worker's pneumoconiosis.

OBJECTIVES: Tumor necrosis factor-alpha (TNF-alpha) may play an important role in host's immune response to mycobacterium tuberculosis (M. tuberculosis) infection. This study was to investigate the association of TNF-alpha gene polymorphism with pulmonary tuberculosis (TB) among patients with coal worker's pneumoconiosis (CWP). METHODS: A case-control study was conducted in 113 patients with confirmed CWP complicated with pulmonary TB and 113 non-TB controls with CWP. They were matched in gender, age, job, and stage of pneumoconiosis. All participants were interviewed with questionnaires and their blood specimens were collected for genetic determination with informed consent. The TNF-alpha gene polymorphism was determined with polymerase chain reaction of restriction fragment length polymorphism (PCR-RFLP). Frequency of genotypes was assessed for Hardy-Weinberg equilibrium by chi-square test or Fisher's exact probability. Factors influencing the association of individual susceptibility with pulmonary TB were evaluated with logistic regression analysis. Gene-environment interaction was evaluated by a multiplicative model with combined OR. All data were analyzed using SAS version 8.2 software. RESULTS: No significant difference in frequency of the TNF-alpha-308 genotype was found between CWP complicated with pulmonary TB and non-TB controls (chi2 = 5.44, P = 0.07). But difference in frequency of the TNF-alpha-308 A allele was identified between them (chi2 = 5.14, P = 0.02). No significant difference in frequencies of the TNF-alpha-238 genotype and allele (P = 0.23 and P = 0.09, respectively) was found between cases and controls either, with combined (GG and AA) OR of 3.96 (95% confidence interval of 1.30-12.09) at the -308 locus of the TNF-alpha gene, as compared to combination of the TNF-alpha-238 GG and TNF-alpha-308 GG genotypes. Multivariate-adjusted odds ratio of the TNF-alpha-238 GG and TNF-alpha-308 GA genotypes was 1.98 (95% CI of 1.06-3.71) for risk for pulmonary TB in patients with CWP. There was a synergic interaction between the TNF-alpha-308 GG genotype and body mass index (OR = 4.92), as well as an interaction between the TNF-alpha-308 GG genotype and history of BCG immunization or history of TB exposure. And, the interaction of the TNF-alpha-238 GG genotype and history of BCG immunization or TB exposure with risk for pulmonary TB in them was also indicated. CONCLUSIONS: TNF-alpha-308 A allele is associated with an elevated risk for pulmonary TB, whereas TNF-alpha-238 A allele was otherwise.

[Study on the determinants of Helicobacter pylori infection among coal miners].

OBJECTIVE: To study the prevalence and determinants of Helicobacter pylori (H. pylori) infection among coal miners and to seek for competent preventive measures. METHODS: 425 coal miners from three coal mines, Tangshan, Daxing, and baodian were chosen under stratified random cluster sampling. Face to face interview was conducted to fill the unified questionnaires by trained interviewers. 306 subjects underwent gastroenduoscopy to detect the situation of the gastroenduodenal diseases, according to the Sydney System of diagnosis. Mucosa biopsies were also undertaken according to the regulated location for culture of H. pylori and for pathological examination. Blood samples were obtained to detect the anti-HpU-IgG by enzyme-linked immunosorbent assay (ELISA). H. pylori infection was determined through culture and ELISA but confirmed under the standards set at the National Congress on Gastroduodenal Diseases in 1999. RESULTS: Among 425 eligible coal miners being tested, 297 (69.9%) were H. pylori positive and the rate for those working underground (74.0%) was higher than that of those working on ground (P=0.004). No difference was found among coal miners between the three mines (P >0.05). Age, living conditions in childhood, number of current family members, the amount of alcohol intake and ways of eating at home were strongly associated with the status of H. pylori infection. CONCLUSIONS: Difference of H. pylori infection prevalences between the underground and the aboveground coal miners was noticed. Determinants that influencing the H. pylori infection would include socioeconomic factors, individual habits and ways of eating at home.