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991.
Shimizu K Hirose N Ebihara Y Arai Y Hamamatsu M Nakazawa S Masui Y Inagaki H Gondo Y Fujimori J Kanno Y Konishi K Kitagawa K 《Experimental gerontology》2004,39(10):1563-1565
The aim of the present study was to investigate the association between blood groups and life expectancy. We compared frequencies of ABO blood group in 269 centenarians (persons over 100 years) living in Tokyo and those in regionally matched controls (n=7153). Frequencies of blood types A, O, B, and AB in centenarians were 34.2, 28.3, 29.4, and 8.2%, respectively, while those in controls were 38.6, 30.1, 21.9, and 9.4%, respectively. Blood type B was observed more frequently in centenarians than in controls (chi(2)=8.41, P=0.04). This tendency also was true in comparison between centenarians and 118 elderly old individuals of the 7153. Approximate one-third of the centenarians were free from serious diseases such as malignancy. However, blood types were not associated with such medical records. Our findings suggest that blood type B might be associated with exceptional longevity. Responsible mechanisms need to be investigated. 相似文献
992.
In this paper, we assess the complexity (fractal measure) of body motion during walking in patients with Parkinson's disease. The body motion of 11 patients with Parkinson's disease and 10 healthy elderly subjects was recorded using a triaxial accelerometry technique. A triaxial accelerometer was attached to the lumbar region. An assessment of the complexity of body motion was made using a maximum-likelihood-estimator-based fractal analysis method. Our data suggest that the fractal measures of the body motion of patients with Parkinson's disease are higher than those of healthy elderly subjects. These results were statistically different in the X (anteroposterior), Y (lateral) and Z (vertical) directions of body motion between patients with Parkinson's disease and the healthy elderly subjects (p < 0.01 in X and Z directions and p < 0.05 in Y direction). The complexity (fractal measure) of body motion can be useful to assess and monitor the output from the motor system during walking in clinical practice. 相似文献
993.
Pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients 总被引:2,自引:0,他引:2
Nagahama H Soejima M Uenomachi H Higashi Y Yotsumoto K Samukawa T Arima T 《Internal medicine (Tokyo, Japan)》2004,43(3):184-188
OBJECTIVE: Obstructive sleep apnea syndrome (OSAS) is associated with increased cardiovascular morbidity and mortality. We investigated the values of brachial-ankle pulse wave velocity as an indicator of atherosclerosis in obstructive sleep apnea syndrome patients. MATERIALS AND METHODS: Brachial-ankle pulse wave velocity (baPWV) was measured in 104 OSAS patients and 104 healthy control subjects matched for age, sex, and body mass index (BMI). BaPWV values were compared in both groups and investigated with respect to the number of risk factors for atherosclerosis, including hypertension, hypercholesterolemia, impaired glucose tolerance, smoking, and obesity. Comparisons were also made between 48 OSAS group cases and 90 control group cases free from hypertension, which has a major impact on baPWV. RESULTS: As compared to the control group, the OSAS group had significantly higher baPWV (1,645+/-349 cm/s vs 1,436+/-278 cm/s, p<0.0001), and values obtained for baPWV were significantly higher in the OSAS group than in the control group even in groups free from hypertension (1,453+/-216 cm/s vs 1,374+/-213 cm/s, p<0.05). In both groups, baPWV rose as the number of risk factors for atherosclerosis increased, but baPWV was higher in the OSAS group than in the control group even in a comparison of individuals entirely free from risk factors (1,400+/-200 cm/s vs 1,198+/-79 cm/s, p<0.05). CONCLUSION: The condition of OSAS itself is considered a possible risk factor for atherosclerosis. We believe that the usefulness of baPWV as an index of atherosclerosis merits further study in the frequently observed cases of OSAS complicated by cardiovascular disease. 相似文献
994.
PKC-independent inhibition of neuronal nicotinic acetylcholine receptors by diacylglycerol 总被引:1,自引:0,他引:1
Diacylglycerol modulates cell functions primarily through activation of protein kinase C (PKC). In a previous study, however, we found that a diacylglycerol analogue, 1-oleoyl-2-acetylglycerol (OAG), accelerated desensitization of neuronal nicotinic acetylcholine receptors (nAchRs) independently of PKC activation in PC12 cells. In the present study, we investigated whether other analogues and endogenous diacylglycerol exert similar effects on neuronal nAchRs and characterized the modulation by diacylglycerol. We measured the nicotine-induced whole-cell current in the absence and presence of diacylglycerol analogues in PC12 cells. We also investigated the effects of a blockade of metabolic pathways of diacylglycerol by inhibiting diacylglycerol lipase and kinase. We found that all four diacylglycerol analogues studied promoted desensitization and depressed the nondesensitized component of the nicotine-induced current. These effects seemed independent of PKC activation because they were not antagonized by the PKC inhibitors staurosporine or bisindolylmaleimide I; one analogue that lacks the PKC-stimulating action was also effective. The effects of diacylglycerol analogues were not antagonized by high doses of nicotine and were independent of the membrane potential. Similar modulatory effects were observed by treatment with RHC80267, a blocker of diacylglycerol lipase, and R59949, an inhibitor of diacylglycerol kinase, in the presence of staurosporine. These results suggest that diacylglycerol, both exogenously applied and endogenously produced, modulates neuronal nAchRs independently of PKC activation in PC12 cells; further, these effects seemed consistent with a noncompetitive and voltage-independent block. They raised the possibility that PKC-independent inhibition of neuronal nAchRs by diacylglycerol may be a novel modulatory process. 相似文献
995.
Neurotransmitters appear to be involved in chemotransmission of the carotid body, a major arterial chemoreceptor. Substantial data indicate that acetylcholine (ACh) is an excitatory neurotransmitter in the carotid body, regulating the excitability of afferent nerve endings and glomus cells (putative chemoreceptor cells). In this study we characterized properties of nicotinic ACh receptors (nAChRs) in cultured cat glomus cells using immunocytochemistry and whole cell patch clamp techniques. Cultured glomus cells expressed immunoreactivity for alpha3, alpha4, and beta2 subunits of nAChRs. An application of ACh elicited inward current. Nicotinic AChRs of glomus cells showed high affinity for ACh. The current-voltage relationship showed strong inward rectification at positive membrane potential. alpha-Conotoxin MII (20 nM), dihydro-beta-erythroidine (DHbetaE; 1 nM), and hexamethonium (300 microM) significantly inhibited ACh-induced current. These results indicate that cultured cat glomus cells possess functional nAChRs, and that their characteristics are consistent with those of alpha3, alpha4 and beta2 containing nAChRs. 相似文献
996.
Hippocampal injury and neurobehavioral deficits are improved by PD 81,723 following hyperglycemic cerebral ischemia 总被引:4,自引:0,他引:4
Meno JR Higashi H Cambray AJ Zhou J D'Ambrosio R Winn HR 《Experimental neurology》2003,183(1):188-196
We investigated the effects of PD 81,723, an allosteric enhancer for the adenosine A(1) receptor subtype, on hippocampal injury and Morris water maze (MWM) performance following hyperglycemic cerebral ischemia and reperfusion (4-VO, 10 min) in the rat. PD 81,723 (3 or 10 mg/kg) or the equivalent volume of saline was administered intraperitoneally 30 min prior to ischemia. Moderate hyperglycemia was achieved by administration of D-glucose (3g/kg, i.p.) 15 min prior to induction of ischemia. Morris water maze trials were performed on the 6th, 7th, and 8th days after the ischemic insult. The rat brains were sectioned (8 microm), stained with cresyl violet/acid fuchsin, and evaluated for hippocampal ischemic injury by an experimenter blinded to the treatment conditions. At the higher dose, PD 81,723 (10 mg/kg) had no effect on hippocampal injury or MWM performance following hyperglycemic ischemia compared to corresponding saline-treated animals. In contrast, a lower dose of PD 81,723 (3 mg/kg) resulted in significant (P < 0.05, n = 8) reduction of hippocampal injury following hyperglycemic ischemia. Furthermore, corresponding Morris water maze performance (latency, learning index, and cumulative distance swum) was significantly improved by PD 81,723 (P < 0.05, n = 8). The results of the present study suggest that, in the presence of PD 81,723, an A(1) allosteric enhancer, endogenously produced adenosine is sufficient to exert significant neuroprotection during hyperglycemic ischemia. Moreover, the present study provides further evidence for a neuromodulatory role of adenosine during hyperglycemic ischemia. 相似文献
997.
The authors describe a family in which two individuals have clinical distal myopathy with rimmed vacuoles (DMRV). While the clinical and most of the pathologic features in these patients were compatible with a diagnosis of DMRV, the presence of inflammatory changes in the connective tissue between muscle fibers was not. Gene analysis revealed a compound heterozygous mutation in these individuals, characterized by V572L and I472T. 相似文献
998.
Shimizu K Takeda S Noji H Hirose N Ebihara Y Arai Y Hamamatsu M Nakazawa S Gondo Y Konishi K 《Journal of nutritional science and vitaminology》2003,49(2):133-138
We have previously reported that centenarians (persons > or = 100 y old) in Tokyo prefer dairy products. Dietary preferences may be associated with longevity. The aim of the present study was to investigate the relationship between dietary patterns and further survival in centenarians. During 1992-1999, we examined the dietary practices of 104 centenarians (29 men and 75 women; mean age, 100.3 +/- 0.9 y) who lived in the Tokyo metropolitan area. Dietary patterns were classified by kappa-means cluster analysis. As clinical co-variables, we considered activities of daily living, cognitive function, nutritional status, presence of important disease, gender, and age at the time of the initial survey. Survival data were recorded yearly until 2001, and then tested with Kaplan-Meier analysis and the log rank statistic. Four dietary patterns were identified: a pattern preferring vegetables (n = 33), a pattern preferring dairy products (n = 26), a pattern preferring beverages (n = 10), and a pattern preferring cereals (n = 35). No clinical variables differed between the four dietary patterns. In 2001, 28 centenarians were still alive. The survival rate for those preferring dairy products was the highest of the four dietary patterns; in particular, being significantly higher than the pattern preferring beverages (p = 0.048). A dietary pattern preferring dairy products was associated with increased survival in Tokyo-area centenarians. 相似文献
999.
We analysed the laminar distribution of transmembrane currents from embryonic (E) day 17 until adulthood after selective thalamic stimulation in slices of rat forebrain to study the development of functional thalamocortical and cortico-cortical connections. At E18 to birth a short-latency current sink was observed in the subplate and layer 6, which was decreased, but not fully abolished in a cobalt containing solution or after the application of glutamate receptor blockers (APV and DNQX). This indicated that embryonic thalamic axons were capable of conducting action potentials to the cortex and some of them had already formed functional synapses there. Between birth and P3, when thalamic axons were completing their upward growth, a sink gradually appeared more superficially in the dense cortical plate and synchronously, a current source aroused in layer 5. Both sinks and sources completely disappeared after blocking synaptic transmission. The adult-like distribution of CSDs became apparent after P7. The component in layer 6 cannot be blocked completely after this age suggesting antidromic activation. This study demonstrated that cells of the lowest layers of the cortex received functional thalamic input before birth and that thalamocortical axons formed synapses with more superficial cells as they grew into the cortical plate. 相似文献
1000.
Clinical value of FDG-PET in the follow up of post-operative patients with endometrial cancer 总被引:5,自引:0,他引:5
Saga T Higashi T Ishimori T Mamede M Nakamoto Y Mukai T Fujita T Togashi K Yura S Higuchi T Kita M Fujii S Konishi J 《Annals of nuclear medicine》2003,17(3):197-203
OBJECTIVE: The clinical usefulness of FDG-PET in the follow up of post-operative patients with endometrial cancer was retrospectively evaluated. METHODS: Twenty-one post-operative patients with endometrial cancer received 30 FDG-PET examinations to evaluate recurrence or response to treatment. The findings of FDG-PET were compared with their serum levels of tumor markers, CT and/or MRI findings, and the final outcome. Results of FDG-PET were also correlated with the clinical course of each patient. RESULTS: In detecting recurrent lesions and evaluating treatment responses, FDG-PET, with the help in anatomic information by CT/MRI, showed better diagnostic ability (sensitivity 100.0%, specificity 88.2%, accuracy 93.3%) compared with combined conventional imaging (sensitivity 84.6%, specificity 85.7%, accuracy 85.0%) and tumor markers (sensitivity 100.0%, specificity 70.6%, accuracy 83.3%). FDG-PET had no false-negative results, suggesting the possibility of its use as the first-line examination in a patient's follow-up. FDG-PET could detect unknown lesions in 4 cases, and, as reported for other malignancies, FDG-PET affected the patient management in one-third of the cases. Furthermore, the results of FDG-PET correlated well with the clinical outcome of the patients, with patients with negative PET results tending to show disease-free courses. CONCLUSIONS: These results suggest that, despite the limited number of patients studied, FDG-PET was accurate in detecting recurrence and evaluating therapeutic response, and could afford important information in the management of post-operative patients with endometrial cancer. FDG-PET also appeared to have a possibility to predict the outcome of each patient. 相似文献