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41.
To investigate the role of the vagus nerve in acute inflammatory and cardiorespiratory responses to diesel particulate (DP) in the rat airway, we measured changes in respiration, blood pressure and neutrophils in lungs of urethane anesthetized Wistar rats 6-h post-instillation of DP (500 microg) and studied the effect of mid-cervical vagotomy or atropine (1 mg kg(-1)) pre-treatment. In conscious rats, we investigated DP, with and without atropine pre-treatment. DP increased neutrophil level in BAL (bronchoalveolar lavage) fluid from intact anesthetized rats to 2.5+/-0.7x10(6) cells (n=8), compared with saline instillation (0.3+/-0.1x10(6), n=7; P<0.05). Vagotomy reduced DP neutrophilia to 0.8+/-0.2x10(6) cells (n=8; P<0.05 vs. intact); atropine reduced DP-induced neutrophilia to 0.3+/-0.2x10(6) (n=4; P<0.05). In conscious rats, DP neutrophilia of 8.5+/-1.8x10(6), n=4, was reduced by pre-treatment with atropine to 2.2+/-1.2x10(6) cells, n=3. Hyperventilation occurred 6 h after DP in anesthetized rats with intact vagi, but not in bilaterally vagotomized or atropine pre-treated animals and was abolished by vagotomy (P<0.05, paired test). There were no significant differences in the other variables (mean blood pressure, heart rate and heart rate variability) measured before and 360 min after DP. In conclusion, DP activates a pro-inflammatory vago-vagal reflex which is reduced by atropine. Muscarinic ACh receptors in the rat lung are involved in DP-induced neutrophilia, and hence muscarinic antagonists may reduce airway and/or cardiovascular inflammation evoked by inhaled atmospheric DP in susceptible individuals.  相似文献   
42.
Jiang J  Ma L  Yuan L  Wang X  Zhang W 《Toxicology》2007,232(3):286-293
The objective of this study was to establish a hypospadiac rat model by maternal exposure to di-n-butyl phthalate (DBP) and to evaluate the developmental abnormalities of hypospadiac male rats. Timed-pregnant rats were given DBP by gastric intubation at doses of 0, 250, 500, 750 or 1000 mg/kg body weight (bw)/day from gestation day (GD) 14 to 18 to establish a hypospadiac rat model. The hypospadias was observed in the 500 and 750 mg/kg bw/day groups, the incidence of which was 6.8 and 41.3%, respectively. Transverse serial histological analysis of genitalia of hypospadiac male rats confirmed the malformation. With exposed dose increasing, the serum testosterone (T) levels of male rats inversely decreased, and in the same dosage group the serum T levels of hypospadiac rats were significantly lower than the levels of nonhypospadiac counterparts. The other reproductive lesions such as cryptorchidism and decreased ratio of anogenital distance/body weight (AGD/bw) were also observed. Autopsy analysis revealed the development of reproductive organs (prostate, testes, epididymis, pituitary gland) and nonreproductive organs (adrenal gland, liver, kidney, heart, spleen) of hypospadiac rats and nonhypospadiac counterparts. The results indicated that the reproductive system and developmental condition of hypospadiac male offspring were damaged severely by DBP.  相似文献   
43.
目的 探讨养血清脑颗粒联合缬沙坦氢氯噻嗪片治疗老年原发性高血压的临床疗效。方法 选取2020年6月—2021年11月在保定市第一医院收治的82例老年原发性高血压患者为观察对象,根据随机数字表法将所有患者分为对照组和治疗组,每组各41例。对照组口服缬沙坦氢氯噻嗪片,1片/次,1次/d;治疗组在对照组治疗的基础上温水冲服养血清脑颗粒,1袋/次,3次/d。两组患者连续治疗3个月。观察两组的临床疗效,比较两组的血压指标、血流动力学指标、血清指标。结果 治疗后,治疗组患者的总有效率为95.12%,对照组的总有效率为80.49%,组间比较差异有统计学意义(P<0.05)。治疗后,两组的24 h收缩压(24 h SBP)、24 h舒张压(24 h DBP)、24 h收缩压标准差(24 h SSD)、24 h舒张压标准差(24 h DSD)明显低于治疗前(P<0.05),且治疗组24 h SBP、24 h DBP、24 h SSD、24 h DSD低于对照组(P<0.05)。治疗后,两组的体循环阻力(SVR)低于治疗前,心排血量(CO)、心脏指数(CI)高于治疗前(P<0.05);并且治疗组的SVR低于对照组,CO、CI高于对照组,差异有统计学意义(P<0.05)。治疗后,两组的血清同型半胱氨酸(Hcy)、内皮素-1(ET-1)水平低于治疗前,一氧化氮(NO)水平高于治疗前(P<0.05);治疗组的Hcy、ET-1水平低于对照组,NO水平高于对照组(P<0.05)。结论 养血清脑颗粒联合缬沙坦氢氯噻嗪片治疗老年原发性高血压的疗效确切,能有效控制血压,改善血流动力学指标和血管内皮功能,安全性良好。  相似文献   
44.

Background

Recent studies have shown that Vitamin D deficiency is very common globally. Vitamin D deficiency is associated with lipid metabolism. A relationship between vitamin D levels and waist circumference (WC) has been observed. The purpose of this study is to evaluate the relationship between vitamin D status and metabolic dyslipidemia and the hypertriglyceridemic waist phenotype.

Methods

This cross-sectional study was conducted on 265 healthy Tehran adults. Hypertriglyceridemic waist phenotype (HTGWP) was described as serum triacylglycerol concentrations >150?mg/dL and concurrent WC?>?88?cm (women) and >102?cm (men). Dyslipidemia was defined as: 1) TG level of >150?mg/dL 2) HDL?>?40?mg/dL for men or >50?mg/dL for women, as has been previously described.

Results

Current study’s results demonstrated that HTGWP was significantly associated with weight, age, WC, hip, fat percent, TG, lipid profile, ALT and BMI. We found 77% reduction in the chances of developing metabolic dyslipidemia in suficient satus of vitamin D in compare to deficiency, although the significancy was mariginal, OR: 0.33, 95% CI of 0.09 to 1.21, P?=?0.09. However, our results revealed that vitamin D deficiency, compared with normal status, can increase the risk of phenotype 1 (high TG/high WC); OR: 3.86 and 95% CI from 0.86 to 0.99, p for trend?=?0.05.

Conclusions

Significant associations were found between vitamin D status and HTGWP. In addition, there was a relationship between vitamin D and lipid profiles. There is a direct correlation between TG and waist circumference in insulin resistance in healthy Tehran adults.  相似文献   
45.
Green tea (GT) consumption is known to be associated with enhanced cardiovascular and metabolic health. The purpose of this study is to examine the hypothesis that supplementation with GT alters insulin resistance and associated cardiovascular risk factors in obese, hypertensive patients. In a double-blind, placebo-controlled trial, 56 obese, hypertensive subjects were randomized to receive a daily supplement of 1 capsule that contained either 379 mg of GT extract (GTE) or a matching placebo, for 3 months. At baseline and after 3 months of treatment, the anthropometric parameters, blood pressure, plasma lipid levels, glucose levels, creatinine levels, tumor necrosis factor α levels, C-reactive protein levels, total antioxidant status, and insulin levels were assessed. Insulin resistance was evaluated according to the homeostasis model assessment–insulin resistance protocol. After 3 months of supplementation, both systolic and diastolic blood pressures had significantly decreased in the GTE group as compared with the placebo group (P < .01). Considerable (P < .01) reductions in fasting serum glucose and insulin levels and insulin resistance were observed in the GTE group when compared with the placebo group. Serum tumor necrosis factor α and C-reactive protein were significantly lower, whereas total antioxidant status increased in the GTE group compared with the placebo (P < .05). Supplementation also contributed to significant (P < .05) decreases in the total and low-density lipoprotein cholesterol and triglycerides, but an increase in high-density lipoprotein cholesterol. In conclusion, daily supplementation with 379 mg of GTE favorably influences blood pressure, insulin resistance, inflammation and oxidative stress, and lipid profile in patients with obesity-related hypertension.  相似文献   
46.

Objectives

The aim was to evaluate the relationships of the T-1131C (rs662799) polymorphism variants of apolipoprotein A5 (Apo A5) gene and variants of apolipoprotein E (Apo E) gene common polymorphism (rs429358, rs7412) to signs of metabolic syndrome (MetS).

Design and methods

We examined 590 asymptomatic dyslipidemic patients divided into MetS + (n = 146) and MetS − (n = 444) groups according to criteria of NCEP ATPIII Panel. We evaluated genotype frequencies and differences in MetS features between individual groups. Logistic regression analysis was used for the evaluation of Apo A5/Apo E variants as possible risk factors for MetS.

Results

We found no statistical differences between genotype and allele frequencies for both Apo A5 and Apo E polymorphisms between MetS + and MetS − groups. In all subjects and MetS − group, we confirmed well-known association of the − 1131C Apo A5 minor allele with elevated triglycerides (TG, p < 0.001). The Apo E gene E2 and E4 variants were associated with higher levels of TG (p < 0.01) in comparison to E33 common variant. However, no statistical differences were observed in MetS + subjects, regardless of significantly higher TG levels in this group. Apo A5/Apo E variant analysis in all dyslipidemic patients revealed significant increase of TG levels in all subgroups in comparison to common − 1131T/E3 variant carriers, the most in − 1131C/E4 variant subgroup. Logistic regression analysis models showed no association of Apo A5, Apo E and all Apo A5/Apo E variants with metabolic syndrome, even after adjustment for age and sex.

Conclusion

Our study refined the role of Apo A5 and Apo E genetic variants in the group of adult dyslipidemic patients. We demonstrate that except of TG, Apo A5 T-1131C (rs662799) and Apo E (rs429358, rs7412) polymorphisms have no remarkable effect on MetS characteristics.  相似文献   
47.
ObjectiveTo determine whether relationships exist between accelerometer-measured moderate-to-vigorous physical activity (MVPA) and other cardiovascular (CV) health metrics in a large sample.Patients and MethodsData from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) collected from January 1, 2003, through December 31, 2006, were used. Overall, 3454 nonpregnant adults 20 years or older who fasted for 6 hours or longer, with valid accelerometer data and with CV health metrics, were included in the study. Blood pressure (BP), body mass index (BMI), smoking status, diet, fasting plasma glucose level, and total cholesterol level were defined as ideal, intermediate, and poor on the basis of American Heart Association criteria. Results were weighted to account for sampling design, oversampling, and nonresponse.ResultsSignificant increasing linear trends in mean daily MVPA were observed across CV health levels for BMI, BP, and fasting plasma glucose (P<.001). Those with a poor BMI and BP had significantly lower mean daily MVPA than those with intermediate and ideal BMIs and BPs (all P<.001). In addition, individuals with an intermediate fasting plasma glucose level had significantly lower mean daily MVPA than individuals at the ideal levels (P<.001). No significant linear trends were observed for cholesterol, smoking, and diet. A significant linear trend was observed for mean daily MVPA and the overall number of other CV health metrics (P<.001).ConclusionObjectively measured MVPA was related to other CV health metrics in this large sample. These results support the inclusion of physical activity in the overall definition of ideal CV health.  相似文献   
48.
BackgroundNighttime environmental noise affects sleep quality. However, the effects of daytime occupational noise remain unclear.MethodsA quasi-experiment of 48 participants who had been employed for at least six months in two hospital cafeterias. The participants were randomly designated to be assessed on high- and low-noise workdays for 8 h or low- and high-noise workdays, separated by a washout period of 14 days. Subsequently, pure tone audiometry, autonomic nervous system (ANS) function tests, serum cortisol tests, and polysomnography were conducted.ResultsFor the 40 participants in the study, the 8-h time-weighted average of personal noise exposed on high- and low-noise workdays was 76.8 dBA (standard deviation, SD: 6.2) and 61.0 dBA (SD: 7.1), respectively. Participants with higher personal noise exposure during the day were found to have a lower percentage of slow wave sleep (percent change of mean value: −1.287%; 95% CI: −2.602%, −0.037%) and lower sleep efficiency (−0.267%; 95% CI: −0.525%, −0.008%). In addition, after work, personal noise exposure was revealed to be related to increased serum cortisol levels (1.698%; 95% CI: 0.887%, 2.528%), and sympathetic activity as measured by low frequency/high frequency (3.000%; 95% CI: 1.294%, 4.706%) and blood pressures by cold pressor test (systolic: 5.163%; 95% CI: 2.780%, 7.537%) (diastolic: 3.109%; 95% CI: 1.604%, 4.614%).ConclusionsDaytime occupational noise exposure had sustained effects on nighttime sleep quality, specifically on slow wave sleep and sleep efficiency. These disturbances could be partially explained by post-shift elevated cortisol and ANS activity. The psychosocial and metabolic consequences of poorer sleep quality induced by occupational noise exposure warrant further investigation.  相似文献   
49.

Objective

An interaction between the endothelin-1 gene (EDN1), blood pressure (BP) and social determinants has been previously found. Using a well-characterized cohort of participants, the impact of associations between genetic factors and job strain on BP was evaluated.

Methods

A cross-sectional analysis of five polymorphisms covering the EDN1, of which 2 were previously reported to be associated with BP, was performed. Study subjects had previously completed a baseline evaluation including 24-h ambulatory BP monitoring and an assessment of job strain. This report presents the findings for 184 subjects who gave DNA samples for genetic analysis. One-way analysis of variance (ANOVA) was performed between each genetic marker and 24-h systolic blood pressure (SBP) and diastolic blood pressure (DBP), as well as two-way ANOVAs to test the interaction effect with job strain.

Results

Trends for relationships were observed between SBP and two polymorphisms: rs10478694 and rs5369. An interaction between job strain and those heterozygous for two polymorphisms showed higher SBP (P=.029 and .008) and a tendency for higher DBP. All findings were more significant when analyses were confined to the 139 Caucasian subjects.

Conclusion

This is the first study to report an interaction between the EDN1 gene, job strain and BP, supporting previous evidence of a role of this gene in the interaction between environmental stress and ambulatory BP. Given the limited sample size, the results should be considered preliminary, and further studies are required.  相似文献   
50.
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