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51.
Cardiac hypertrophy and left ventricular hypertrophy are known to be substantially controlled by genetic factors. As an experimental model, we undertook genome-wide screens for cardiac mass in F2 populations bred from the stroke-prone spontaneously hypertensive rats (SHRSP) and normal spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) of a Japanese colony. Two F2 cohorts were independently produced: F2(SHRSP x WKY) (110 male and 110 female rats) and F2(SHR x WKY) (151 male rats). The ratio of heart weight to body weight (Hw/Bw) was evaluated at 12 months of age in F2(SHRSP x WKY) after salt-loading for 7 months, and at around 15 weeks of age in F2(SHR x WKY) who had been fed a normal rat chow diet. Subsequent to an initial screen with 251 markers in F2(SHRSP x WKY) male progeny, 170 and 161 markers were selected and characterized in F2(SHRSP x WKY) female progeny and F2(SHR x WKY) male progeny, respectively. Markers from four chromosomal regions showed suggestive or significant linkage to Hw/Bw. The strongest and the most consistent linkage was found in the vicinity of D3Mgh16 on rat chromosome (RNO) 3 (a maximal log of the odds score reached 4.0 to 6.6 across the F2 populations studied). In the other three regions on RNO6, RNO10 and RNO13, the degree of linkage was more prominent in either males or females. These data provide solid evidence for a "principal" RNO3 quantitative trait loci regulating Hw/Bw in SHRSP and SHR, and also suggest the possible presence of sexual dimorphism in regard to genetic susceptibility for cardiac hypertrophy.  相似文献   
52.
Previous studies have found markedly elevated serum concentrations of proinflammatory cytokines in patients with Graves’ disease (GD). We investigated the role of macrophage colony-stimulating factor (M-CSF) in GD. We assayed concentrations of M-CSF in sera from 32 patients with GD (25 untreated; 7 receiving thiamazole therapy). We also studied 32 age-matched healthy subjects as controls. Relationships between serum M-CSF and both thyroid state and serum lipids were examined. Moreover, to examine the effect of thyroid hormone alone on serum M-CSF, T3 was administered orally to normal subjects. Serum concentrations of M-CSF in GD patients who were hyperthyroid were significantly increased compared with GD patients who were euthyroid (P < 0.05) and control subjects (P < 0.0001). Serum M-CSF concentrations correlated closely with T3 levels in patients (= 0.51, < 0.005). Serial measurement of five individual patients revealed that serum concentrations of M-CSF were significantly decreased (P < 0.05), reaching normal control values upon attainment of euthyroidism. Furthermore, oral T3 administered to 15 volunteers for 7 days produced significant increases in serum levels of M-CSF (< 0.05). The close correlation between serum M-CSF and serum thyroid hormone levels suggests that high circulating levels of thyroid hormones may directly or indirectly potentiate the production of M-CSF in patients with GD.  相似文献   
53.
A case of familial spinocerebellar ataxia 6 with typical symptoms is presented. A 60-year-old Japanese female suffered from gait disturbance, ataxia and dizziness. Head magnetic resonance imaging revealed a typical atrophic image in cerebellum. Genetic tests revealed an expanded allele of 22 CAG repeats at the spinocerebellar ataxia type 6 locus. She was diagnosed with spinocerebellar ataxia 6. Her mother was also diagnosed with the same disease. A mixture of 18 medicinal herbs (modified Zhengan Xifeng Tang) was given according to the differential diagnosis based on the guidelines of traditional Chinese medicine. All of the symptoms were remarkably improved after 60 days of the herbal treatment. One year after discontinuation of the treatment, she complained of gait ataxia. She was treated with the modified Zhengan Xifeng Tang for 60 days. Gait ataxia was markedly improved by the second treatment. Fifteen months after discontinuation of the second treatment, she complained of gait ataxia again. The same remedy was given for 60 days. Gait ataxia was remarkably reduced again. The results may imply therapeutic potential of the medicinal herbs for spinocerebellar ataxia 6.  相似文献   
54.
Granulomatous hypophysitis with meningitis and hypopituitarism.   总被引:2,自引:0,他引:2  
We report an unusual case of granulomatous hypophysitis in which visual impairment, meningitis and hypopituitarism in a 76-year-old female were associated with radiological evidence of a pituitary mass. The sellar lesion was indistinguishable from pituitary tumor on neuroimaging studies, but the recovery of visual acuity and visual field abnormalities together with the improvement of pituitary function after steroid administration indicated that the mass lesion was due to an inflammatory disease of the pituitary gland. The pituitary tissue obtained by transsphenoidal hypophysectomy revealed granulomatous inflammatory cell infiltration with epithelioid cells and scattered multinucleated giant cells. Although a causal relationship with meningitis was not ascertained, possible exposure of the CSF space to the autoimmune inflammatory process of the pituitary gland was likely in view of the positive pituitary antibody reaction and radiological evidence of suprasellar extension. This entity should be considered when evaluating patients with a pituitary mass, hypopituitarism and meningitis.  相似文献   
55.
A 9‐year‐old girl developed influenza A H1N1 pdm09‐associated myocarditis and pericarditis 2 days after starting zanamivir therapy. The virus was detected in the respiratory tract but not in the serum or pericardial effusion. The virus sampled from the respiratory tract had normal susceptibility to neuraminidase inhibitors. Although no differences in interferon‐γ, interleukin (IL)‐1β, and tumor necrosis factor‐α were observed between the plasma and pericardial effusion, some inflammatory cytokines or chemokines (IL‐6 and IL‐8) and vascular endothelial growth factor were remarkably elevated in the pericardial effusion compared with the plasma. This suggested that the influenza virus, after infecting the respiratory tract, affected the myocardium, causing myocarditis to gradually develop, which might have been followed by an autoreactive pericarditis causing increased pericardial effusion. Therefore, influenza‐associated myocarditis should be considered when influenza patients have respiratory and cardiac involvement, even during treatment with a neuraminidase inhibitor.  相似文献   
56.
Ionizing radiation (IR) induces cellular stress responses, such as signal transduction, gene expression, protein modification, and metabolite change that affect cellular behavior. We analyzed X-irradiated human Epstein-Barr virus-transformed B lymphoblastoid cells and normal fibroblasts to search for metabolites that would be suitable IR-responsive markers by Liquid Chromotography–Mass spectrometry (LC–MS). Mass spectra, as analyzed with principal component analysis, showed that the proportion of peaks with IR-induced change was relatively small compared with the influence of culture time. Dozens of peaks that had either been upregulated or downregulated by IR were extracted as candidate IR markers. The IR-changed peaks were identified by comparing mock-treated groups to 100 mGy-irradiated groups that had recovered after 10 h, and the results indicated that the metabolites involved in nucleoside synthesis increased and that some acylcarnitine levels decreased in B lymphoblastoids. Some peaks changed by as much as 20 mGy, indicating the presence of an IR-sensitive signal transduction/metabolism control mechanism in these cells. On the other hand, we could not find common IR-changed peaks in fibroblasts of different origin. These data suggest that cell phenotype-specific pathways exist, even in low-dose responses, and could determine cell behavior.  相似文献   
57.
BackgroundAlthough high-dose glucocorticoids are effective in suppressing active inflammation of Takayasu arteritis (TAK), many patients experience relapse during tapering of glucocorticoids. Recently, the interleukin-6 receptor antibody, tocilizumab (TCZ), was reported to be effective for steroid-resistant TAK. However, there are no objective ways of diagnosing TAK recurrence because TCZ suppresses inflammatory biomarkers.ObjectivesTo investigate the efficacy of TCZ at 1-year follow-up and of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography for detection of recurrence of inflammation during TCZ treatment.Methods and ResultsWe treated 19 patients with refractory TAK with TCZ. TCZ was discontinued in 2 cases because of side effects. Abatement of arteritis symptoms along with reduction of glucocorticoid dosage was achieved in 12 patients, resulting in a remission induction rate of 70.6%. The dosage of glucocorticoid was reduced from 16.1 ± 10.2 mg to 3.8 ± 1.7 mg at 1 year (p<0.001) in these patients. In the remaining 5 patients, glucocorticoid tapering led to exacerbation of symptoms and glucocorticoid dose had to be increased. FDG-PET scan results closely matched clinical course in all 5 patients with recurrence even during TCZ treatment, while the scan was negative for the remaining 12 patients.ConclusionsTCZ injection provides robust steroid-sparing effect and improvement of inflammation without significant adverse effects. Recurrence of inflammation can be detected by FDG-PET even during TCZ treatment.  相似文献   
58.
Shoulder injuries in the athlete   总被引:1,自引:0,他引:1  
Shoulder injuries are common in the athletic population. Injuries can be a result of repetitive overhead use or from direct trauma. Common injury sites include the rotator cuff, glenohumeral joint, acromioclavicular joint, biceps tendon, scapulothoracic articulation, and sternoclavicular joint. The identification, physical exam, and treatment options of these conditions will be discussed.  相似文献   
59.
BACKGROUND: A prospective study examined whether a combination of an exercise program and heparin administration improves the clinical symptoms of patients with arteriosclerosis obliterans (ASO) without an indication for surgical revascularization because of the lack of distal target vessels or other reasons such as high surgical risk or lack of a vein conduit from previous coronary artery bypass surgery. METHODS AND RESULTS: A total of 19 consecutive patients with symptomatic non-option ASO diagnosed by angiography were randomly assigned to 3 groups: heparin + exercise (walking for 60 min after heparin injection [3,000 units/day IV for 14 days], n = 6), heparin administration only (n = 6), and exercise only (n = 7). Plasma levels of hepatocyte growth factor (HGF) were serially measured before and after intravenous administration of heparin. Ankle brachial pressure index was measured and treadmill exercise test (2.5 km/h, 12% slope) was performed before the 2-week treatment, just after finishing treatment, and 12 weeks after beginning the treatment. Ophthalmic examinations, including visual acuity test, ocular fundoscopy and fluorescein angiographic fundus photography, were performed before and 12 weeks after the treatment program. In all patients, HGF levels increased more than 4-fold of the basal level at 30 min after heparin injection. Maximum walking time was significantly higher in the heparin + exercise group than in the other 2 groups (p < 0.05). There were no patients who showed pathological retinal angiogenesis. CONCLUSION: The combination of an exercise program and heparin administration improves the clinical symptoms of patients with non-option ASO.  相似文献   
60.
假设:随着时间的流逝,结核感染者记忆性T细胞对特异性抗原的应答减弱。背景:很多证据表明特异性全血γ-干扰素(IFN-γ)检测试验Quanti—FERON~TB Gold(QFT—G)能够检测出近期结核感染者,并具有较高的灵敏度和特异性。目的:我们应用此项技术检测日本一个社区的成人群体以确定其流行病学应用价值。方法:1559例参加定期体检的健康志愿者入选本研究。结果:40~49岁人群QFT—G的阳性率为3.1%,50~59岁人群的阳性率为5.9%,60~69岁人群的阳性率为9.8%。作者根据一系列研究估计40~49岁、50~59岁、60~69岁的预期结核感染率分别为11.1%、29.6%、53.1%。预期阳性率与实际阳性率之间存在的巨大差异提示结核感染后随着时间的延长IFN-γ应答减弱。那些经胸部X线证实存在陈旧性结核病灶者阳性率大大低于100%。结论:特异性IFN—γ应答可能在结核感染后随着时间的推移大大地减弱。需要在感染者中长期地纵向研究细胞介导的免疫动力学。  相似文献   
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