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101.
A role for neuropeptide W in the regulation of feeding behavior   总被引:1,自引:0,他引:1  
Neuropeptide W (NPW) is a novel hypothalamic peptide that activates the previously described orphan G protein-coupled receptors, GPR7 and GPR8. Two endogenous molecular forms of NPW that consist of 23- and 30-amino acid residues were identified. The localization of GPR7 and GPR8 in some hypothalamic regions of primary importance in the regulation of feeding behavior has provided a springboard for investigation of the role of NPW in the central nervous system. In this study we examined the effects of NPW on feeding and energy expenditure in rats. Single intracerebroventricular (i.c.v.) administration of NPW23 and NPW30 to free-feeding rats suppressed dark phase and fasting-induced food intake at similar effective doses. Continuous i.c.v. infusion of NPW using an osmotic minipump suppressed feeding and body weight gain over the infusion period. Conversely, i.c.v. administration of anti-NPW IgG stimulated feeding. Furthermore, i.c.v. administration of NPW increased body temperature and heat production. These data raise the possibility that NPW functions as an endogenous catabolic signaling molecule in the brain. Further investigation of the biochemical and physiological functions of NPW will help us to better understand the hypothalamic regulation of energy homeostasis.  相似文献   
102.
Thermogenesis in the brown adipose tissue (BAT) is activated by the stimulation of the ventromedial hypothalamic nucleus (VMH). Local warming of the preoptic area (PO) suppresses this response. Injection of the GABA(A) receptor antagonist bicuculline into the caudal periaqueductal gray (cPAG), where excitatory neurons for BAT thermogenesis are located, did not influence the suppressive effect of PO warming. On the other hand, after bicuculline injection into the raphé pallidus, where excitatory neurons for BAT thermogenesis are also located, VMH stimulation produced BAT thermogenesis even during PO warming. The present results suggest that the inhibitory signal from the PO reaches the raphé pallidus and not the cPAG for the control of BAT thermogenesis.  相似文献   
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BACKGROUND: Although epidemiologic studies of the general population have demonstrated a deficit of blood group O among patients with deep venous thrombosis (DVT), few studies have evaluated the importance of blood group in high-risk patients. The purpose of this study was to evaluate the importance of ABO blood group as a thrombotic risk factor in injured patients. METHODS: Injured patients with a discharge diagnosis of DVT were identified from an institutional trauma registry and compared with control patients matched for age and Injury Severity Score. ABO blood types of patients and controls were obtained from the regional blood center database. RESULTS: Three hundred forty-three case-control pairs were identified from a total of 401 consecutive cases of DVT. Blunt injury was the predominant mechanism of injury, accounting for 90.4% of cases. Chest (p = 0.01) and extremity (p < 0.001) Abbreviated Injury Scale scores were independent predictors of DVT. However, there was no significant difference in blood group distribution or the A to O ratio between patients with and without DVT. For non-type O patients, the odds ratio for developing DVT was 1.1 (95% confidence interval, 0.8-1.5; p = 0.5) in comparison with type O patients. CONCLUSION: These data do not support a clinically relevant association between blood type and DVT in trauma patients. Injury-associated derangements of coagulation may be more important than any hypercoagulability related to blood type in this population.  相似文献   
106.
A 65-year-old woman was referred to our clinic with gross hematuria. Cystoscopy revealed a non-papillary and non-pedunculated tumor on the left lateral wall of the bladder. A piece of necrotic tissue obtained from the bladder irrigation was histologically squamous cell carcinoma. A perforation at the left lateral wall of the bladder was found on the cystogram. Bone scintigraphy showed multiple metastases and computed tomography scans showed multiple lymph node metastases in the pelvic cavity. The clinical diagnosis was bladder carcinoma of T4N2M1 stage with an abscess due to a spontaneous perforation. Total cystectomy with bilateral ureterocutaneostomy was performed. She died due to sepsis 13 days after the operation. Histologically, the tumor was composed of carcinomatous and sarcomatous elements. The carcinomatous element was compatible with squamous cell carcinoma and the sarcomatous element was composed of undifferentiated malignant spindle cells. Immunohistochemical examination showed that the carcinomatous component was positive for keratin and human chorionic gonadotropin (HCG) and the spindle cell component positive for vimentin, desmin and HCG. Therefore, we diagnosed the tumor as sarcomatoid carcinoma. We reviewed 56 cases of carcinosarcoma of the bladder in Japan and discussed the clinicopathology of the disease.  相似文献   
107.
Mild hyperhomocysteinemia is one of the known strong risk factors for atherosclerotic diseases, and therefore it is important to clarify factors that could determine plasma total homocysteine (tHcy) level. A cross-sectional study with a random sample of 455 Japanese rural residents aged 40-69 years was conducted in 2000 to investigate the associations of plasma tHcy concentration with 5,10-methylenetetrahydrofolate reductase (MTHFR) gene and selected life-style related factors. The frequency of the mutant allele, Valine (V) allele, was 0.40 and the prevalence of VV genotype was 14.3%. Plasma tHcy concentration in VV was significantly higher than those in two other genotypes. There were significant inverse associations of plasma tHcy with serum folate and serum vitamin B12 (P<0.001 for trend, respectively); both being stronger in VV than in other genotypes. The number of cigarettes smoked per day was positively associated with plasma tHcy concentration. A multivariate regression analysis revealed that serum folate, serum vitamin B12, and MTHFR genotype were independently associated with plasma tHcy. The inter-individual variance of plasma tHcy was more explained by serum folate and vitamin B12 than by MTHFR genotype. Higher intakes of folate, vitamin B12, and non-smoking may be important to prevent mild hyperhomocysteinemia and the eventual atherosclerotic diseases in this Japanese rural population.  相似文献   
108.
BACKGROUND: Patients with recurrent soft tissue sarcoma (STS) are seldom curable, with 5-year survival rates of less than 10% in all large series. The role of high-dose chemotherapy (HDC) with hematopoietic stem cell support in this disease has not been established. CASE REPORT: We report on two patients with recurrent STS who were treated with tandem HDC supported by autologous peripheral blood stem cell transplantation (PBSCT). One patient with malignant fibrous histiocytoma recurred with multiple lung metastases. This patient achieved a partial response after two cycles of induction chemotherapy consisting of ifosfamide and epirubicin. During four cycles of induction chemotherapy, peripheral blood stem cells (PBSCs) were harvested. Tandem high-dose ICE regimen (ifosfamide 3 g/m2 on days-7 to -3, carboplatin 400 mg/m2 on days-7, -5 and 3, etoposide 500 mg/m2 on days-7, -5 and 3) supported by autologous PBSCT gave rise to further regression of the tumors. Another patient with malignant hemangiopericytoma was treated by tandem high-dose ICE regimen supported by autologous PBSCT after the 3rd removal of abdominal tumors. Relapse-free intervals until the 1st, 2nd and 3rd relapses were 40, 19 and 22 months, respectively. Tandem high-dose ICE regimen might delay the relapse. CONCLUSION: These observations suggest that a tandem high-dose ICE regimen with autologous PBSCT is feasible with some clinical efficacy in the control of refractory STS.  相似文献   
109.
We report herein a case of spindle cell type hepatocellular carcinoma responding to hepatic intra-arterial infusion chemotherapy. A 50-year-old woman was hospitalized for right epigastralgia. A computed tomography scan demonstrated cloudy liver tumor with a diameter of 12 cm in S5 and S8. Surgery was performed based on the diagnosis of liver tumor. However, because the tumor was also present in the left lobe, we did only a biopsy for a part of tumor. From the pathological findings, this was diagnosed as a spindle cell type hepatocellular carcinoma. After the operation, hepatic intra-arterial injection therapy of continuous infusion with 5-FU was conducted for two weeks. A small reduction in the tumor was seen with computed tomography after the completion of two courses.  相似文献   
110.
BACKGROUND: Cardioversion of chronic atrial fibrillation or atrial flutter to sinus rhythm is often associated with transient atrial mechanical dysfunction, i.e. 'atrial stunning', which may increase the risk of subsequent thromboembolic events. We hypothesized that, because of its positive inotropic action, a low-dose isoproterenol infusion might improve postcardioversion atrial mechanical function. METHOD: Eighteen patients (15 male, three female; 12 atrial fibrillation, six atrial flutter; mean age 65+/-10 years) exhibiting atrial postcardioversion stunning were included in the study. Isoproterenol was infused for 10 min at a dose sufficient to increase the heart rate by about 10%. Using transesophageal echocardiography, both the left atrial appendage emptying/filling flow velocity and function (fractional area change) were examined at baseline, before isoproterenol (immediately after cardioversion) and after isoproterenol. RESULTS: With infusion of 0.005-0.008 microg/kg/min isoproterenol, heart rate increased by 11.1+/-2.9%, and left atrial appendage emptying velocity, which was diminished following cardioversion, increased significantly (P<0.001) (baseline, before and after isoproterenol: 41.1+/-18.0, 20.3+/-8.5 and 27.3+/-9.6 cm/s, respectively). No major complications were associated with isoproterenol infusion. CONCLUSIONS: Short-term infusion of low-dose isoproterenol improved atrial function after cardioversion of chronic atrial fibrillation and atrial flutter.  相似文献   
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