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51.
E Kita  M Emoto  F Nishikawa  Y Yoshikai    S Kashiba 《Immunology》1995,86(2):206-211
Conversion of Salmonella typhimurium to L-forms, both in vitro and in vivo, resulted in the expression of proteins cross-reacting to the mycobacterial 65,000 MW heat-shock protein (hsp). Immunization of C3H/HeJ mice with a protective dose of stable L-form S. typhimurium induced gamma delta T cells in the liver, in accordance with the multiplication of L-form Salmonella in Kupffer cells. The number of gamma delta T cells decreased after the intracellular growth of L-form Salmonella plateaued. Persistance of the L-forms in Kupffer cells, however, allowed hepatic gamma delta T cells to increase within 48 hr of infection with virulent S. typhimurium. Thus, the intrahepatic colonization of L-form Salmonella seems to keep gamma delta T cells on standby, but the emergence of these T cells does not correlate with the expression of L-form hsp. In addition, Kupffer cells colonized by L-forms constitutively synthesized mRNA for interleukin-6 (IL-6) and tumour necrosis factor-alpha (TNF-alpha). These results suggest that conversion of S. typhimurium to L-forms in phagocytic cells builds up and maintains acquired resistance, conferred by live-cell vaccines of S. typhimurium, against murine typhoid.  相似文献   
52.
To evaluate the function of the central nervous system of patients with occupational vibration disease, electroencephalograms and auditory brainstem responses (ABR) were recorded in 20 male subjects with occupational vibration disease whose age ranged from 46 to 67 years (mean 57.4 yr). All the subjects had operated chain saws from 10 to 25 yr (mean 15.2 yr) and had frequently complained of many subjective symptoms induced by central nervous system disturbances such as headache, head heaviness, tinnitus, vertigo, and insomnia, which corresponded to stage 3 in the diagnostic criteria of Andreeva-Galanina. Twenty-six healthy men whose age ranged from 40 to 67 yr (mean 53.0 yr) were selected as controls. Electroencephalograms were recorded with a 12-channel electroencephalograph, using unipolar and bipolar leads. Auditory brainstem responses were recorded by signal averaging technique using 100 microseconds alternating clicks. The stimuli were presented at 70 dB above threshold (SL) with a rate of 10 per second. The following results were obtained. 1. By electroencephalography, the incidence of diffuse alpha pattern, slow alpha wave and drowsy pattern was 32%, 32%, and 42%, respectively. 2. Click thresholds in the patients were obviously higher than those in the healthy controls. 3. The occurrence rate of wave II of ABR in the patients (61.8%) was significantly lower than that in the healthy controls (85.0%) (p less than 0.05). 4. The interpeak latencies I-V and III-V of ABR in the patients were significantly longer than those in the healthy controls.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
53.
The nature of epidermal growth factor (EGF) receptors in normal and pathological thyroid membranes was studied on a crude membrane fraction (10,000 X g pellet) of tissue homogenate. Optimal binding of 125I-EGF to human thyroid membranes was obtained at 25 degrees C with 1-h incubation at pH 7.4. The study revealed the presence of both high and low affinity receptors in normal and pathological thyroid membranes. The association constants of high affinity receptor (3.2 X 10(-9) mol/l) and of low affinity receptor (1.8 X 10(-8) mol/l) observed in normal thyroid membranes were similar to those of thyroid membranes from neoplastic as well as thyrotoxic thyroid tissues. [3H]thymidine incorporation into DNA of cultured human thyroid cells was stimulated by EGF in a dose-dependent manner. A half-maximal stimulation was found around 1 X 10(-10) mol/l. These results suggest that EGF may have a possible role in the regulation of thyroid growth and function in physiological and pathological situations.  相似文献   
54.
We studied the copper concentrations in the non-cancerous and cancerous liver tissues of LEC rats with hereditary hepatitis and spontaneous hepatoma by atomic absorption spectrophotometry. Copper concentration in the non-cancerous livers of 29-month-old male LEC rats was comparable to that in the livers of LEC rats aged 2, 3 and 8 months whose hepatic copper concentrations were more than 40 times those of normal LEA rats. Copper concentration in spontaneously developed hepatocellular carcinomas of the 29-month-old male LEC rats was lower than that in the surrounding non-cancerous liver tissues, but was still more than 39 times that of 8-month-old male LEA rats. These findings suggest that in LEC rats an abnormal copper metabolism may be maintained during the process of hepatic carcinogenesis.  相似文献   
55.
BACKGROUND: Prediction of the extent of calcium supplement will facilitate safe and efficient management of hypocalcemia in the early postoperative stage of total parathyroidectomy with autotransplantation (PTXa) in patients with renal osteodystrophy. METHODS: The correlation between the extent of calcium deficiency, estimated by the amount of calcium supplement over 48 h after PTXa and using various parameters such as carboxy terminal parathyroid hormone (c-PTH), intact PTH (i-PTH), alkaline phosphatase (ALP), serum calcium, serum phosphorus, duration of hemodialysis, total weight of resected parathyroid glands and degree of subperiosteal resorption of the middle phalanx was examined in 49 patients who underwent PTX with subcutaneous autotransplantation. Bone mineral density (BMD) was also determined before, 3 months and 1 year after PTXa with dual energy X-ray absorptiometry (DEXA) in 13 patients. RESULTS: There was a positive correlation between pre-operative i-PTH level (r=0.56, P<0.0005) or ALP level (r=0.50, P<0.0005) and the amount of calcium supplement over 48 h after PTXa in these patients. Furthermore, the degree of subperiosteal resorption, determined by Jensen's classification, was significantly correlated with the amount of calcium supplement after PTX (P<0.05). Bone mineral density 3 months after (P<0.0005) and 1 year after PTXa (P<0.001) significantly increased compared with BMD before PTXa in all patients examined. CONCLUSION: These findings suggest that the pre-operative determination of i-PTH, ALP levels and degree of subperiosteal resorption allow the management of hypocalcemia safely and efficiently in renal osteodystrophy patients after PTXa.  相似文献   
56.
To diagnose latent dilated cardiomyopathy (latent DCM), we performed loading echocardiography with Angiotensin II and ergometer exercise in 41 patients. Twenty-one patients were suspected of having latent DCM because of histories, of heart failure of myocarditis; 10 patients had DCM; and 10 normal persons served as controls. On angiotensin II loading, cardiac function deteriorated in the DCM group, but it was maintained in the normal controls. Nine patients in the latent DCM group showed the same pattern as normals (L1-group), and 12 did as the DCM group (L2-group). Although % fractional shortening, end-diastolic and end-systolic dimensions of the left ventricle did not differ between the L1 and L2-groups, the A/R, the ratio of the pulsed Doppler echocardiogram at the left ventricular inflow tract, was larger and the exercise change of the % fractional shortening and exercise tolerance were less in the L2-group than in the L1-group. Furthermore, the biopsy findings of the L2-group were similar to those of the DCM group in terms of myocardial degeneration, myocardial hypertrophy and interstitial fibrosis. Thus, patients in the L2-group were thought to have a risk for DCM, and were cases of latent DCM. Angiotensin II loading is thought to be useful for diagnosing such cases.  相似文献   
57.
58.
OBJECTIVE: To assess the impacts of insulin resistance and renal function on plasma total homocysteine (tHcy) levels in patients with type 2 diabetes with a wide range of nephropathy. RESEARCH DESIGN AND METHODS: Plasma tHcy levels were measured using the enzyme immunoassay method in 75 patients with type 2 diabetes and compared with those in 54 healthy control subjects. Insulin sensitivity indexes were assessed in patients with type 2 diabetes by hyperinsulinemic-euglycemic clamp using artificial pancreas. RESULTS: Plasma tHcy levels and their log-translormed values (log tHcy) were significantly higher in all patients with diabetes than in control subjects (tHcy, 12.0 +/- 0.7 [SE] vs. 8.7 +/- 0.3 micromol/l, P < 0.0001; log tHcy, 1.040 +/- 0.021 vs. 0.920 +/- 0.016 micromol/l, P < 0.0001). Plasma tHcy levels in patients with diabetes were significantly increased according to degree of nephropathy (P < 0.0001). On simple regression analyses, log tHcy correlated with insulin sensitivity indexes (r = -0.319, P = 0.005) as well as creatinine clearance (r = 0.634, P < 0.0001) in all patients with diabetes. Multiple regression analyses showed that insulin sensitivity indexes (beta = -0.245) as well as creatinine clearance were independent contributors to log tHcy in all patients with diabetes (R2 = 0.750, P < 0.0001). For the 59 patients with diabetes with creatinine clearance >60 ml/min, insulin sensitivity indexes were also shown to be a significant contributor to log tHcy (beta = -0.438, R2 = 0.561, P < 0.001). CONCLUSION: Insulin resistance and renal function are independent determinants of tHcy levels in patients with type 2 diabetes.  相似文献   
59.
OBJECTIVE: ACE and endothelial cell nitric oxide synthase (ecNOS) genotypes have been reported to be related to the incidence of renal diseases and coronary artery diseases. In order to assess the effect of the gene polymorphism of both ACE and ecNOS on renal hemodynamic abnormality, we examined 155 Japanese patients with type 2 diabetes with various stages of nephropathy. RESEARCH DESIGN AND METHODS: The patients ranged in age from 40 to 72 years (92 men and 63 women). They were divided into four groups: group 1 consisted of patients with urinary albumin excretion (UAE) <30 mg/day (n = 69), group 2 had 30 < or = UAE < 300 mg/day (n = 44), group 3 had UAE > or =300 mg/day and serum creatinine <1.5 mg/dl (n = 22), and group 4 had serum creatinine >1.5 mg/dl (n = 20). Intrarenal hemodynamics were studied by duplex Doppler sonography in patients with type 2 diabetes. The ACE and ecNOS gene polymorphisms were examined by polymerase chain reaction. RESULTS: There were no significant differences in sex, BMI, and blood glucose level, but there were differences in HbA(1c) and lipoprotein profiles among the four groups. There were no significant differences in the distribution of ACE genotype or in the frequency of the ecNOS 4a allele among the four groups. Resistive index (RI) values of the interlobar arteries of group 4 were significantly higher than those of groups 1, 2, and 3, whereas the RI values were not significantly different among groups 1, 2, and 3. Multiple regression analysis showed that age, duration of diabetes, systolic and diastolic blood pressure, and creatinine clearance were significantly associated with the increased RI values, but that there was no significant association between RI values and the ecNOS genotype (R(2) = 0.613, P < 0.0001). CONCLUSIONS: These results suggest that intrarenal hemodynamic abnormalities are present as a feature of the progression of nephropathy in type 2 diabetes, and that they are associated with age, duration of diabetes, decreased creatinine clearance, and blood pressure, but not with the genetic factors of the ACE and ecNOS gene polymorphism in nephropathy of type 2 diabetes.  相似文献   
60.
The present study was undertaken to assess the effect of hyperthyroidism on stiffness in the common carotid artery (CCA) in patients with Graves' disease (GD) and elucidate the mechanism by which arterial stiffness is increased in hyperthyroidism. The arterial stiffness index beta (stiffness beta) was evaluated in the CCA using an ultrasonic phase-locked echo-tracking system. Stiffness beta was defined as the logarithm of the ratio of systolic to diastolic blood pressure divided by the fractional diameter increase during the cardiac cycle and thus established as a measure of arterial stiffness uninfluenced by the change in blood pressure. Seventy euthyroid GD patients were measured for CCA stiffness beta to determine its relationship to retinal blood flow and plasma levels of vascular injury markers. To investigate the effect of hyperthyroidism, 27 GD patients were measured for changes during antithyroid drug (ATD) therapy in stiffness beta and in hemodynamic parameters, retinal blood flow and plasma vascular injury markers. In euthyroid GD patients, stiffness beta in the CCA showed a significant and positive correlation with systolic blood pressure and pulse pressure, but not with peripheral blood flow in the central retinal artery. ATD therapy significantly reduced stiffness beta from 5.23 +/- 2.10 to 4.36 +/- 1.48. The fractional reduction of stiffness beta during ATD therapy correlated significantly with reductions in pulse pressure and retinal blood flow, but not with the reductions in systolic and mean blood pressure, or any of the plasma injury markers. In summary, the significant increase in stiffness beta in the hyperthyroid state may reflect the harmful effect of hyperthyroidism on the arterial wall, which may in turn result from increased stroke volume.  相似文献   
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