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41.
Multiple myeloma (MM) cells cause devastating bone destruction by activating osteoclasts in the bone marrow milieu. However, the mechanism of enhanced bone resorption in patients with myeloma is poorly understood. In the present study, we investigated a role of C-C chemokines, macrophage inflammatory protein (MIP)-1alpha and MIP-1beta, in MM cell-induced osteolysis. These chemokines were produced and secreted by a majority of MM cell lines as well as primary MM cells from patients. Secretion of MIP-1alpha and MIP-1beta correlated well with the ability of myeloma cells to enhance osteoclastic bone resorption both in vitro and in vivo as well as in MM patients. In osteoclastogenic cultures of rabbit bone cells, cocultures with myeloma cells as well as addition of myeloma cell-conditioned media enhanced both formation of osteoclastlike cells and resorption pits to an extent comparable to the effect of recombinant MIP-1alpha and MIP-1beta. Importantly, these effects were mostly reversed by neutralizing antibodies against MIP-1alpha and MIP-1beta, or their cognate receptor, CCR5, suggesting critical roles of these chemokines. We also demonstrated that stromal cells express CCR5 and that recombinant MIP-1alpha and MIP-1beta induce expression of receptor activator of nuclear factor-kappaB (RANK) ligand by stromal cells, thereby stimulating osteoclast differentiation of preosteoclastic cells. These results suggest that MIP-1alpha and MIP-1beta may be major osteoclast-activating factors produced by MM cells.  相似文献   
42.
Metastatic malignant melanoma (MM) of the liver evolving into acute hepatic failure is a rare occurrence. We describe the case of an 82-year-old man with a history of MM on the left thumb treated with amputation and chemotherapy 40 months previously. On admission, he had abdominal pain, weight loss, lethargy and jaundice. Radiologic investigations such as enhanced computed tomography and abdominal ultrasound failed to establish an etiologic diagnosis. A liver biopsy revealed amelanotic melanoma cells diffusely infiltrating the hepatic parenchyma. His liver injury progressed and the patient died of hepatic failure on the 13th hospital day. Autopsy revealed >70% infiltration by metastatic amelanotic melanoma in the liver.  相似文献   
43.
Abstract We investigated the effects of nifedipine on splanchnic haemodynamics in 13 patients with cirrhosis and portal hypertension, and in 10 control subjects using hepatic venous catheterization and pulsed Doppler ultrasound. There were no significant changes in systemic or splanchnic haemodynamics in control patients. In contrast, systemic vascodilatation, evidenced by significant decreases in mean arterial pressure and systemic vascular resistance, was observed in patients 20 min after sublingual application of 10 mg nifedipine. Moreover, hepatic venous pressure gradient and portal vein blood flow significantly increased after nifedipine administration. There was a significant correlation between the percentage increases in portal vein blood flow and in hepatic venous pressure gradient. However, no correlation was found between the percentage change in cardiac output and that in portal vein blood flow. Thus the increase in portal vein blood flow appears to be related to splanchnic arterial vasodilatation by nifedipine. Consequently, nifedipine has deleterious effects on portal haemodynamics in patients with cirrhosis. As nifedipine may potentially increase the risk of variceal haemorrhage in patients with less advanced varices, this drug should be used with caution in patients with chronic liver disease.  相似文献   
44.
The therapeutic effect of a new synthetic protease inhibitor on hemodynamic changes was studied in experimental acute pancreatitis. Pancreatitis was induced by the injection of autologous bile mixed with trypsin into the main pancreatic duct after ligating the accessory duct. Plasma beta-endorphin concentrations and cardiovascular function were measured. Seventeen dogs (control group) were given 10 ml/kg/hr of lactate Ringer’s solution intravenously 1 hr before the induction of pancreatitis and throughout the experiment. Seven dogs (the low protease inhibitor group) were given an intravenous bolus injection of 0.4mg/kg of a new synthetic protease inhibitor, E-3123 (4-(2-succiminido-ethylthio)4-geranidinobenzoate methanesulfate) 30 min after the induction of pancreatitis and then a continuous intravenous infusion at 3 Μg/kg/min throughout the experiment. Seven dogs (the high protease inhibitor group) received an intravenous bolus injection of 3 mg/kg and a continuous intravenous infusion at 50 Μg/kg/min of E-3123 according to the same method as in the low protease inhibitor group. The mortality rate during the experiment was 41% (7/17) in the control group, 28.5% (2/7) in the high protease inhibitor group and 0% in the low protease inhibitor group. The increase in the plasma beta-endorphin levels in the control group was statistically significant. When E-3123 was given 30 min after the induction of pancreatitis, the increase in the plasma beta-endorphin levels in the high protease inhibitor group was also found to be increased statistically significant, compared with preinduction levels, but the increase was statistically significantly lower than that in the control group. Plasma beta-endorphin levels in the low protease inhibitor group, however, did not increase. The protease inhibitor infusion as used in this experiment can bring about improvement in hypotension and myocardial depression to an extent by inhibiting the release of betaendorphin, suggesting that the inhibitory effect of the protease inhibitor on beta-endorphin release contributes to the improvement in hemodynamic changes during pancreatitis. There may also be an optimal therapeutic dose of this drug for the treatment of hypotension and myocardial depression secondary to betaendorphin release. This work was supported in part by a grant-in-aid from the Japanese Ministry of Health and Welfare (Pancreatic Disease) and Grant 03670638 from the Japanese Ministry of Education, Science and Culture.  相似文献   
45.
The Dahl salt-sensitive (DS) rat is the most prevalently used animal model of salt-sensitive hypertension. The purpose of the present study was to test the hypothesis that mitochondrial DNA (mtDNA) polymorphisms influence blood pressure in DS rats. We produced two strains of female F1 rats, one from female DS and male Lewis rats (DL) and the other from Lewis female and DS male rats (LD). These two strains had the same autosomal genetic background, but their mitochondria had different origins. The DL and LD rats had DS and Lewis mitochondria, respectively. A high-salt diet was started at 4 weeks of age. Radiotelemetry devices were implanted into the lower abdominal aorta of these F1 rats at 9 weeks of age. Blood pressure was monitored for 24 h at 11, 12, 13, 14, and 19 weeks of age. No significant differences were observed in blood pressure levels between the strains. Although more than 100 polymorphisms were detected between DS and Lewis rats, it is unlikely that polymorphisms in mtDNA contribute to hypertension in DS rats. Moreover, we found no difference between DS and Lewis rats in the mtDNA copy number in the kidneys, the liver, and the ventricles of the heart before and after salt loading. Thus, it is unlikely that mitochondrial dysfunction due to high blood pressure exacerbated target organ damage. Intriguingly, the time course of body weight gain differed significantly between DL and LD F1 rats, suggesting the influence of mitochondrial polymorphisms on body composition.  相似文献   
46.
Abstract  Four all-night polysomnograms of a 39-year-old male patient with non-24 h sleep-wake syndrome were recorded. We analysed electroencephalograms (EEG) with the power spectrum method and the wave pattern recognition analysis of Fujimori. The EEC of the rest waking condition showed normal patterns. High-voltage diffuse alpha band waves were observed in sleep stages 2, 3 and 4. The integrated area of the alpha band waves in the analysis epochs showed a strong positive correlation to the delta hand components in the power spectrum of the same epoch during sleep (correlation coefficients r = 0.762–0.815). Alpha hand waves during sleep were clearly different from the alpha waves in the rest waking condition, with respect to slower peak frequency and the frontal dominant voltage distribution.  相似文献   
47.
A case of mosaic 9p tetrasomy (46,XX/47,XX, + dic[9] [q21]) is reported. Clinical manifestations of the patient were generalized hypotonia, severe mental retardation and characteristic dysmorphic features of 9p tetrasomy. A brief review of the literature is also included.  相似文献   
48.
We report a case of a non-Hodgkin's lymphoma (NHL) patient treated successfully with combination chemotherapy during pregnancy who delivered a full-term baby. A 29 year-old patient with cervical and inguinal lymphadenopathy in the 27th week of gestation was referred to our hospital. The diagnosis of lymph node biopsy was NHL (diffuse, large cell type with B-cell phenotype). Three courses of CHOP regimen (adriamycin, cyclophosphamide, vincristine and prednisolone) were given before delivery. The patient has been in complete remission for three years and her baby has been in normal development. Our case supports previous reports that chemotherapy in the third trimester may be given safely on NHL patients.  相似文献   
49.
The purpose of this study was to clarify the relationship between lower birth weight and current overweight status and to examine the involvement of these factors in the development of the metabolic syndrome (MS) in obese Japanese children. We examined 97 obese boys (mean age 11.3 years; mean percentage overweight [POW] 52.4%) and 29 obese girls (mean age 11.1 years; mean POW 58.3%). The anthropometric measurements, blood pressure, fasting serum insulin and blood glucose, liver enzymes, lipids and lipoproteins were measured. Birth weight and gestational weeks were also recorded. The subjects were divided into either an MS group or a Non-MS group using criteria proposed for Japanese children. We compared the weight parameters (birth weight, current weight and current weight-to-birth weight ratio [WBWR]) between the two groups and analyzed the relationships between the weight parameters and metabolic derangements. There were no significant differences in age or anthropometric measurements between the two groups. However, birth weight in the MS group was lower than that in the Non-MS group, while WBWR of the MS group was higher than that in the Non-MS group. Blood pressure and serum insulin correlated positively with WBWR. These findings suggested that lower birth weight with current overweight status was associated with the MS in obese Japanese children. We were unable to clarify whether subjects with lower birth weight who achieved proper weight gains had the same risk as subjects with appropriate birth weight. However, they should be assisted to grow adequately to prevent future metabolic derangements.  相似文献   
50.
The coagulation disturbance observed during severe acute pancreatitis before and after the infusion of a new synthetic low molecular weight protease inhibitor (Fut-175) was compared. The coagulofibrinolytic changes after acute pancreatitis was induced by the intraductal injection of an autologous bile and trypsin mixture showed decreased platelet counts, decreased plasma fibrinogen levels, prolonged partial prothrombin time and increased fibrinogen degradation products. In addition, markers of hypercoagulation showed increased fibrin-opeptide A and decreased antithrombin III. The two markers of fibrinolysis showed increased Bβ15–42 immunoreactive peptide and decreased α2 antiplasmin. After the infusisn of Fut-175, the coagulo-fibrinolytic abnormalities, which were bserved during severe acute pancreatitis without infusion of Fut-175, were improved. Furthermore, Fut-175 could suppress the rise in fibrino-peptide A and Bβ15–42 immunoreactive peptide and decrease in antithrombin III and α2 antiplasmin. Thus, Fut-175 seems to be an effective inhitor of protease-mediated hypercoagulation and fibrinolysis in severe acute pancreatitis. This work is supported by a part of grant-in aid of pancreatic disease of Japanese Ministry of Health and Welfare.  相似文献   
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