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41.

Objectives  

Overweight and poor psychological well-being are becoming serious health issues in the Japanese workplace. Concurrence of those physical and mental conditions has been pointed out, especially in middle-aged workers. Therefore, we tried to determine common risk factors for body weight gain and the deterioration of psychological well-being in male middle-aged office workers using a five-year follow-up study.  相似文献   
42.
The effect of a dietary supplement with L-carnitine (600 mg/day) and Garcinia cambogia extract (500 mg/day as hydroxycitric acid) as main ingredients was studied in 35 healthy volunteers {48.3 +/- 6.9 years, body mass index (BMI): 26.3 +/- 1.7} in a double-blind test (18 subjects in the Test Group and 17 in the Control Group). The yearly examination includes the standard yearly medical tests done in Japan, tests for assessing hormonal age, and a survey for assessing physical and mental fitness of the subjects, called the Anti-Aging QOL Common Questionnaire (AAQol). Use of this supplement significantly improved the level of lipid peroxides (-12.8%) in the blood as well as physical symptoms such as "tired eyes," "blurry eyes," "muscle pain/stiffness," "early satiety," "epigastralgia," "dizziness," "arthralgia" and "easily breaking into a sweat." The Control Group showed a significantly favorable improvement rate, especially for "dizziness." On the other hand, groups of subjects using the test compounds saw a significant rise in total cholesterol (4.5%), fasting blood sugar (4.1%) and HbA1c (3.4%). Our findings suggest that the consumption of the supplement can reduce the oxidative damage; however, the effect on QOL was equivocal. Garcinia cambogia extract did not show dietary efficacy.  相似文献   
43.
Bicuspid aortic valve (BAV) is a common congenital heart disease, and it is well known to be a risk factor for ascending aortic dilatation and dissection. We here report a case of 34-year-old woman who underwent Ross procedure with ascending aortic replacement under the diagnosis of subaortic stenosis and ascending aortic aneurysm. She was pointed out to have heart murmur soon after the birth diagnosed as patent ductus arteriosus. The ductus was ligated when she was 3-years-old, however, heart murmur remained. Further examinations revealed that she also had aortic stenosis with BAV. During her 20-year-follow-up, subaortic stenosis and ascending aorta ectasia were also progressed. Pathological examinations of resected ascending aortic wall showed mucoid degeneration and laceration of collagen fibers, suggesting the fragility of dilated aortic wall with BAV.  相似文献   
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The mechanism responsible for cardiac depression in septic shock remains unknown. The present study examined whether nitric oxide (NO) overproduced by inducible NO synthase (iNOS) can inhibit aerobic energy metabolism and impair the myocardial function in endotoxin-treated rat hearts. Lipopolysaccharide (LPS) significantly decreased systolic blood pressure (BP) to 44% of control during the 48 h treatment. Hearts from control and LPS-treated rats were perfused in a Langendorff apparatus. After LPS injection, left ventricular (LV) developed pressure (LVDP) was significantly depressed, plasma NO2-/NO3- (NO(x)) concentration was markedly increased, and myocardial adenosine 5'-triphosphate (ATP), creatine phosphate (CrP), and the ratio of ATP/adenosine 5'-diphosphate were progressively decreased with time. Immunological examination showed a significant expression of iNOS protein in the LPS-treated myocytes. Aminoguanidine, an inhibitor of iNOS, significantly attenuated these LPS-induced functional and metabolic changes. Myocardial cyclic guanosine 3',5'-monophosphate (cGMP) content was significantly increased after LPS injection. Methylene blue, an inhibitor of soluble guanylate cyclase, blunted this increase in cGMP and significantly restored the LPS-induced contractile dysfunction 6 h after LPS injection. In addition, there was a significant negative correlation between LVDP and myocardial cGMP levels as well as a significant negative correlation between LVDP and plasma NO(x) levels. In contrast, 48 h after LPS injection, methylene blue no longer affected cardiac performance, and there was a significant positive correlation between LVDP and myocardial ATP content. Furthermore, the normalized activities (as a ratio of the citrate synthase activity) of mitochondrial NADH-CoQ reductase, succinate-CoQ reductase, and ATPase, were significantly inhibited, and the swelling or disruption of mitochondria cristae was seen in the 48 h LPS treatment. These LPS-induced functional and morphological disorders in the mitochondria were significantly improved by aminoguanidine. The findings suggest that sustained production of NO by iNOS leads to contractile dysfunction via cGMP in the early stage, but that it can directly impair the mitochondrial function, lower myocardial energy production, and contribute significantly to the myocardial dysfunction in the later stage of septic shock.  相似文献   
49.
Aims This study compares serum markers of myocardial damage incurred during radiofrequency catheter ablation (RFCA). Methods and results Blood was sampled from 34 patients with atrial flutter (n = 16), atrioventricular nodal reentrant tachycardia (AVNRT; n = 13), and Wolff–Parkinson–White syndrome (WPW; n = 5) to measure creatine kinase MB subfraction (CK-MB), human heart-type fatty acid protein (h-FABP), and cardiac troponin T (cTnT) values at baseline and after RFCA. The controls comprised 12 patients without significant elevation of all myocardial markers during electrophysiological study (EPS) without RFCA. h-FABP values did not elevate significantly, whereas CK-MB and cTnT demonstrated significant change after RFCA (P < 0.001). Neither peak h-FABP nor CK-MB correlated with following RFCA parameters: delivery duration, number of RFCA discharges, and cumulative RFCA energy. In contrast, correlations were significant between mean peak values of cTnT and these RFCA parameters (all P < 0.05). The sensitivity (71.6%) and specificity (35.6%) of h-FABP were inferior to those of cTnT (93.3% and 89.8%, respectively). Conclusion h-FABP is an insensitive and less specific marker of myocardial damage in RFCA much along the lines of CK-MB and when compared with the proven accuracy of cTnT.  相似文献   
50.
An endocochlear potential (EP) of +80 mV is essential for audition. Although the regulation of K(+) concentration ([K(+)]) in various compartments of the cochlear stria vascularis seems crucial for the formation of the EP, the mechanism remains uncertain. We have used multibarreled electrodes to measure the potential, [K(+)], and input resistance in each compartment of the stria vascularis. The stria faces two fluids, perilymph and endolymph, and contains an extracelluar compartment, the intrastrial space (IS), surrounded by two epithelial layers, the marginal cell (MC) layer and that composed of intermediate and basal cells. Fluid in the IS exhibits a low [K(+)] and a positive potential, called the intrastrial potential (ISP). We found that the input resistance of the IS was high, indicating this space is electrically isolated from the neighboring extracellular fluids. This arrangement is indispensable for maintaining positive ISP. Inhibiting the K(+) transporters of the stria by anoxia, ouabain, or bumetanide caused the [K(+)] of the IS to increase and the intracellular [K(+)] of MCs to decrease, reducing both the ISP and the EP. Calculations indicate that the ISP represents the K(+) diffusion potential across the apical membranes of intermediate cells through Ba(2+)-sensitive K(+) channels. The K(+) diffusion potential across the apical membranes of MCs also contributes to the EP. Because the EP depends on two K(+) diffusion potentials and an electrical barrier in the stria vascularis, interference with any of these elements can interrupt hearing.  相似文献   
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