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排序方式: 共有1470条查询结果,搜索用时 15 毫秒
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Hirotsugu Yamada MD PhD Zoran B. Popovic MD PhD David O. Martin MD MPH Kenneth C. Civello MD MPH Don W. Wallick PhD 《Heart rhythm》2006,3(6):722-727
BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied. 相似文献
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Hirotsugu Ueshima 《Hypertension research》2006,29(11):835-836
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Masahiko Yanagita Bradley J Willcox Kamal H Masaki Randi Chen Qimei He Beatriz L Rodriguez Hirotsugu Ueshima J David Curb 《The American journal of geriatric psychiatry》2006,14(12):1060-1068
OBJECTIVE: The objective of this study was to examine the relation of physical performance measures with depressive symptoms in older men. METHOD: A cross-sectional, multivariate comparison of several measures of upper- and lower-extremity performance and their relation with depressive symptoms was performed in 2,856 older Japanese American men, aged 71-93 years, who participated in the fourth examination of the Honolulu Heart Program. Depressive symptoms were measured using an 11-item version of Center for Epidemiologic Studies Depression (CES-D) Scale. A score of at least 9 (from a maximum score of 33) is considered clinically significant. Timed functional performance tests, including walking and repeated chair stands, were used to assess lower-extremity performance; handgrip strength was used as an indicator of upper-extremity performance. RESULTS: Two hundred eighty-three participants (9.9%) had a score of 9 or greater on the 11-question CES-D Scale and were considered to be at high risk for depression. Time to walk 10 feet and time to complete five chair stands were significantly longer in those with depressive symptoms, whereas handgrip strength was significantly lower. Only the association of gait speed (time to walk 10 feet) and depressive symptoms remained significant when all physical performance measures were simultaneously included in a multivariate analysis. CONCLUSION: These results demonstrate physical performance measures, particularly gait speed, may be important potential correlates of depression in community-dwelling older men. 相似文献
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Hirotsugu Kojima Syunji Sasaki Tetsuya Tamaki Hiroshi Kameda Satoru Yamasaki Michio Kimura 《Medical Electron Microscopy》1994,27(2):149-158
An ultrastructural study was undertaken concerning morphological changes within the autografted patellar tendon (PT) after
being transplanted to the anterior cruciate ligament (ACL) in mongrel dogs. After 4 weeks, the arrangements of both large
and small collagen fibrils in the PT graft became disordered, and the number of inflammatory cells increased. However, the
same PT grafts revealed postsurgical signs of newly-produced collagen fibrils around activated fibroblasts at 12 to 24 weeks.
At 52 weeks after the transplantation, small collagen fibrils increased in both number and density, showing a remarkable morphological
similarity to the collagen fibrils of normal ACL. These data indicate that the characteristics of the PT graft eventually
resemble those of a normal ACL.
This paper was presented in part at the Combined Meeting of the Orthopedic Research Societies of the USA, Japan and Canada
in Banff, Alberta, Canada, October, 1991. 相似文献
8.
P. H. Langsjoen K. Folkers K. Lyson K. Muratsu T. Lyson P. Langsjoen 《Journal of molecular medicine (Berlin, Germany)》1988,66(13):583-590
Summary Coenzyme Q10 (CoQ10) is indispensable in mitochondrial bioenergetics and for human life to exist. 88/115 patients completed a trial of therapy with CoQ10 for cardiomyopathy. Patients were selected on the basis of clinical criteria,X-rays, electrocardiograms, echocardiography, and coronary angiography. Responses were monitored by ejection fractions, cardiac output, and improvements in functional classifications (NYHA). Of the 88 patients 75%–85% showed statistically significant increases in two monitored cardiac parameters. Patients with the lowest ejection fractions (approx. 10%–30%) showed the highest increases (115%–210%) and those with higher ejection fractions (50%–80%) showed increases of approx. 10%–25% on therapy. By functional classification, 17/21 in class IV, 52/62 in class III, and 4/5 in class II improved to lower classes. Clinical responses appeared over variable times, and are presumably based on mechanisms of DNA-RNA-protein synthesis of apoenzymes which restore levels of CoQ10 enzymes in a deficiency state. 10/21 (48%) of patients in class IV, 26/62 (42%) in class III, and 2/5 (40%) in class II had exceptionally low control blood levels of CoQ10. Clinical responses on therapy with CoQ10 appear maximal with blood levels of approx. 2.5 µg CoQ10/ml and higher during therapy.Abbreviations CHF
Congestive heart failure
- CO
Cardiac output
- CoQ10
Coenzyme Q10
- EF
Ejection fraction
- IC
Impedance cardiography
- NYHA
New York Heart Association
- STI
Systolic time interval 相似文献
9.
In an attempt to clarify the mechanism(s) of increased susceptibility to oral infection in diabetics, we examined the levels of salivary antibacterial factors, including lysozyme, lactoperoxidase, and lactoferrin, in diabetic hamsters whose condition was induced with streptozotocin. Saliva was collected from these hamsters periodically for 19 weeks after the administration of streptozotocin. Diabetes persisted with significant hyperglycemia throughout the experiment after a single injection of streptozotocin. There was no significant difference between groups in the amount of saliva secreted. In diabetic hamsters, lysozyme activity decreased by 56% and lactoperoxidase activity decreased by 53% compared with the control hamsters 19 weeks after the administration of streptozotocin. There was no significant difference between groups in the amount of salivary lactoferrin. However, the ratio of lactoferrin to total protein increased to approximately double the amount of that of the control hamsters. Insulin treatment had a significant effect on lysozyme and lactoperoxidase activity, recovering 73 and 74% those of the controls, respectively, and the ratio of lactoferrin to total salivary protein reverted to normal values. Growth inhibition of Lactobacillus plantarum ATCC 8014 with whole saliva and amylase activity significantly decreased in diabetic hamsters. The position of each protein band of whole saliva on sodium dodecyl sulfate-polyacrylamide gel electrophoresis was almost the same for control and diabetic hamsters; however, there was some variability in band intensity. 相似文献
10.
Kenya Kusunose Yuichiro Okushi Yoshihiro Okayama Robert Zheng Miho Abe Michikazu Nakai Yoko Sumita Takayuki Ise Takeshi Tobiume Koji Yamaguchi Shusuke Yagi Daiju Fukuda Hirotsugu Yamada Takeshi Soeki Tetsuzo Wakatsuki Masataka Sata 《Nutrients》2021,13(2)
A broad range of chronic conditions, including heart failure (HF), have been associated with vitamin D deficiency. Existing clinical trials involving vitamin D supplementation in chronic HF patients have been inconclusive. We sought to evaluate the outcomes of patients with vitamin D supplementation, compared with a matched cohort using real-world big data of HF hospitalization. This study was based on the Diagnosis Procedure Combination database in the Japanese Registry of All Cardiac and Vascular Datasets (JROAD-DPC). After exclusion criteria, we identified 93,692 patients who were first hospitalized with HF between April 2012 and March 2017 (mean age was 79 ± 12 years, and 52.2% were male). Propensity score (PS) was estimated with logistic regression model, with vitamin D supplementation as the dependent variable and clinically relevant covariates. On PS-matched analysis with 10,974 patients, patients with vitamin D supplementation had lower total in-hospital mortality (6.5 vs. 9.4%, odds ratio: 0.67, p < 0.001) and in-hospital mortality within 7 days and 30 days (0.9 vs. 2.5%, OR, 0.34, and 3.8 vs. 6.5%, OR: 0.56, both p < 0.001). In the sub-group analysis, mortalities in patients with age < 75, diabetes, dyslipidemia, atrial arrhythmia, cancer, renin-angiotensin system blocker, and β-blocker were not affected by vitamin D supplementation. Patients with vitamin D supplementation had a lower in-hospital mortality for HF than patients without vitamin D supplementation in the propensity matched cohort. The identification of specific clinical characteristics in patients benefitting from vitamin D may be useful for determining targets of future randomized control trials. 相似文献