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Traumatic brain injury (TBI) was shown to lead to the development of cerebral microbleeds (CMBs), which are associated with long term cognitive decline and gait disturbances in patients. The elderly is one of the most vulnerable parts of the population to suffer TBI. Importantly, ageing is known to exacerbate microvascular fragility and to promote the formation of CMBs. In this overview, the effect of ageing is discussed on the development and characteristics of TBI-related CMBs, with special emphasis on CMBs associated with mild TBI. Four cases of TBI-related CMBs are described to illustrate the concept that ageing exacerbates the deleterious microvascular effects of TBI and that similar brain trauma may induce more CMBs in old patients than in young ones. Recommendations are made for future prospective studies to establish the mechanistic effects of ageing on the formation of CMBs after TBI, and to determine long-term consequences of CMBs on clinically relevant outcome measures including cognitive performance, gait and balance function.

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BACKGROUND: The small dense low-density lipoprotein (LDL) phenotype (pattern B), high concentrations of remnant-like particles (RLPs), and postprandial lipemia are newly recognized risk factors for coronary heart disease (CHD). However, the associations of these lipoprotein abnormalities remain unclear. The aim of this study was to investigate the relationships among LDL phenotype, very-low-density lipoprotein (VLDL) subclasses, and postprandial lipoprotein metabolism in CHD patients. METHOD: We performed an oral fat tolerance test in 32 patients with acute myocardial infarction and compared the following parameters between patients characterized by either large buoyant LDL (pattern A) versus pattern B: lipids and apolipoproteins (apo) in the plasma and Svedberg flotation rates (Sf) >400 (chylomicron), Sf 60-400 (large VLDL), and Sf 20-60 (small VLDL) fractions. RESULT: Fasting levels of triglyceride, RLP-cholesterol and RLP-triglyceride were slightly higher in the pattern B patients. Postprandial increases of RLP-cholesterol and the cholesterol and triglyceride of large VLDL fractions were significantly greater in the pattern B patients. The areas under the curves of cholesterol, triglyceride, and apo-B in large VLDL fractions were significantly higher in pattern B, while those in small VLDL were not. RLP-cholesterol and RLP-triglyceride in fasting and fed states correlated very highly with the corresponding cholesterol and triglyceride concentrations in large VLDL fractions. CONCLUSION: These results suggest that postprandial increase of large VLDL fractions and RLPs contribute to the formation of small dense LDL in CHD patients.  相似文献   
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Secretion of aldosterone from aldosterone-producing adenoma (APA) is to some degree under the control of ACTH and the suppressible effect of glucocorticoid on plasma aldosterone concentration (PAC) and blood pressure has been reported to be transient. We report a rare case of aldosteronism due to APA in which PAC and blood pressure were well controlled with small dose dexamethasone for over one year. No chimeric gene of glucocorticoid-remediable aldosteronism (GRA) was found in DNA of APA and leukocytes from peripheral blood and 17alpha-hydroxylase deficiency (17-OH-D) was ruled out by endocrinological examinations, this case indicates the possibility of an unknown mechanism of ACTH-dependent APA.  相似文献   
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To assess the clinical value of transesophageal Doppler echography in the diagnosis of dissecting aortic aneurysm, both transesophageal and conventional echograms were performed in 22 cases of dissecting aortic aneurysm. Of the 22 patients, 17 underwent angiography; 8, X-ray computed tomography; 4, both; and 12, surgery. The performance of each method was assessed in the following four segments: A, ascending aorta; B, aortic arch; C, thoracic descending aorta; and D, upper abdominal aorta. The results by angiography were presumed to be correct. In the group of 17 patients who underwent angiography, the rate of correct detection of an intimal flap using the transesophageal approach was 100% in all four segments, significantly better than detection by the conventional approach (segment A, 65%; segment B, 47%; segment C, 35%; segment D, 53%) (p less than 0.01), and the rate of correct detection of the entry sites using the transesophageal approach was 100%, significantly better than that by conventional approach (42%) (p less than 0.05). X-ray computed tomography was not capable of detecting the site of entry in all cases. The presence of thrombus, aortic regurgitation and pericardial hemorrhage were all revealed clearly by the transesophageal approach, and the results were partly proved by other methods. In conclusion, transesophageal Doppler echography provides a rapid and accurate method of diagnosing and evaluating dissecting aortic aneurysm and permits prompt initiation of appropriate treatment.  相似文献   
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Multifocal cerebral microhemorrhages (CMHs, also known as “cerebral microbleeds”), which are associated with rupture of small intracerebral vessels, have been recognized as an important cause for cognitive decline in older adults. Although recent studies demonstrate that CMHs are highly prevalent in patients 65 and older, many aspects of the pathogenesis and clinical significance of CMHs remain obscure. In this longitudinal observational study, a case of a 77-year-old man with multifocal CMHs is described, in whom the rupture of intracerebral vessels could be linked to repeatedly performing extended Valsalva maneuvers. This patient was initially seen with acute aphasia after performing a prolonged Valsalva maneuver during underwater swimming. T2-weighted magnetic resonance imaging revealed a left acute frontal intracerebral hemorrhage (ICH) with multiple CMHs. The aphasia was resolved and no cognitive impairment was present. Two years later, he developed unsteadiness and confusion after performing two prolonged Valsalva maneuvers during underwater swimming separated by about 12 days. Repeat brain imaging revealed an acute right and a subacute left ICH, with a marked interval increase in the number of CMHs. The patient also exhibited manifest memory loss after the second admission and was diagnosed with dementia. These observations suggest that prolonged Valsalva maneuver is potentially a common precipitating cause of both CMHs and symptomatic ICHs. The Valsalva maneuver both increases the systolic arterial pressure and gives rise to a venous pressure wave transmitted to the brain in the absence of the competent antireflux jugular vein valves. This pressure increase is superimposed on existing hypertension and/or increases in blood pressure due to exercise and increased venous return due to immersion of the body in water. We advocate that further studies are needed to distinguish between CMHs with arterial and venous origins and their potential to lead to ICH induced by Valsalva maneuver as well as to determine whether these lesions have a predilection for a particular location.  相似文献   
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Objective: In 2020, coronavirus disease-2019 (COVID-19) became the cause of a pandemic. In response, the Japan Sports Agency issued warnings about secondary damage to health, such as the threat to physical and mental well-being due to the lack of exercise in this situation. In this study, we report on cross-sectional and longitudinal examinations of standing trunk flexion to evaluate how temporary long-term school closures affected musculoskeletal function in elementary school students.Patients and Methods: All children in one public elementary school in T-city during the school years 2019 and 2020 were included in this study. A digital forward flexion meter was used to measure standing trunk flexion.Results: In this study, 284 (284/289: 98.3%) and 266 (266/274: 97.1%) children in school years 2020 and 2019, respectively, were found to have valid data for cross-sectional analysis. The standing trunk flexion did not show significant differences between grades or sexes. In the longitudinal analysis, the results of the comparison of standing trunk flexion in children for two consecutive years revealed significant differences only between grades 3 and 4 (P<0.05) and between girls in grades 3 and 4 (P<0.01), but no significant differences in other grades or among boys or girls were observed.Conclusion: Initially, we expected that there would be a difference in the results of functional assessment using standing trunk flexion depending on the period of absence from school. However, the results of this study showed no significant changes in standing trunk flexion. Moreover, since children’s musculoskeletal functions may be affected by various factors during the COVID-19 pandemic, they should be carefully monitored in the future.  相似文献   
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