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151.
Ovulation is caused by a sequence of neuroendocrine events: GnRH and LH surges that are induced by positive feedback action of estrogen secreted by the mature ovarian follicles. The central mechanism of positive feedback action of estrogen on GnRH/LH secretion, however, is not fully understood yet. The present study examined whether metastin, the product of metastasis suppressor gene KiSS-1, is a central neuropeptide regulating GnRH/LH surge and then estrous cyclicity in the female rat. Metastin had a profound stimulation on LH secretion by acting on the preoptic area (POA), where most GnRH neurons projecting to the median eminence are located, because injection of metastin into the third ventricle or POA increased plasma LH concentrations in estrogen-primed ovariectomized rats. Metastin neurons were immunohistochemically found in the arcuate nucleus (ARC) to be colocalized with estrogen receptors with some fibers in the preoptic area (POA) in close apposition with GnRH neuronal cell bodies or fibers. Quantitative RT-PCR has revealed that KiSS-1 and GPR54 mRNAs were expressed in the ARC and POA, respectively. The blockade of local metastin action in the POA with a specific monoclonal antibody to rat metastin completely abolished proestrous LH surge and inhibited estrous cyclicity. Metastin-immunoreactive cell bodies in the ARC showed a marked increase and c-Fos expression in the early proestrus afternoon compared with the day of diestrus. Thus, metastin released in the POA is involved in inducing the preovulatory LH surge and regulating estrous cyclicity.  相似文献   
152.
Endothelin-1 (ET-1), a 21-amino acid vasoconstrictive peptide, increases intracellular Ca2+ level and has hypertrophic action on ventricular myocytes. To elucidate a possible role of Ca2+ entry through sarcolemmal Ca2+ channels on this ET-1 action, we examined effects of ET-1 on L-type (ICa,L) and T-type (ICa,T) Ca2+ currents in cultured neonatal rat ventricular myocytes using the patch-clamp technique. ET-1 at a concentration of 10 nM increased the maximum current density of ICa,T from -3.0 +/- 1.4 microA/cm2 in the control condition to -4.4 +/- 1.6 microA/cm2 (p < 0.01). Although the peak amplitude of ICa,L was decreased during ET-1 application (from -9.7 +/- 1.9 microA/cm2 in the control condition to -5.0 +/- 1.4 microA/cm2 [p < 0.01]), this magnitude of decrease in ICa,T (52 +/- 19%) was comparable to that of spontaneous "run-down" of ICa,L (47 +/- 26%). The enhancement of ICa,T by ET-1 was dose dependent; it was initiated as low as 0.32 nM, and the maximal response was attained at approximately 10 nM, with a half-maximal dose of 1.26 nM. The enhancement of ICa,T by ET-1 was antagonized by protein kinase C inhibitors staurosporine (0.2 microM) and 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, 20 microM) applied to the pipette solution. Extracellular application of tumor-promoting phorbol esters, phorbol 12,13-dibutyrate (PDBu) and 4 beta-phorbol 12-myristate 13-acetate, augmented ICa,T. PDBu (0.2 microM) increased the maximal current density of ICa,T from -4.2 +/- 0.5 microA/cm2 in the control condition to -5.5 +/- 1.0 microA/cm2 (p < 0.01). In the presence of H-7 (20 microM) in the pipette solution, PDBu failed to enhance ICa,T, and an inactive isomer of PDBu (4 alpha-phorbol 12,13-dibutyrate, 0.2 microM) did not augment ICa,T. Thus, ET-1 enhances Ca2+ entry through the sarcolemmal T-type Ca2+ channel, possibly through a pathway involving activation of protein kinase C. This ET-1 action may be involved in the rise of the intracellular Ca2+ level and may contribute to the induction of cardiac hypertrophy by ET-1.  相似文献   
153.
B-cell lymphoma associated with haemophagocytic syndrome (HPS) is extremely rare in Western countries but has recently been increasingly reported in Asian countries. We describe seven patients with B-cell lymphoma associated with HPS, six males and one female, age range 41-82 years (median 63 years). All patients had fever and splenomegaly, and six of the seven patients had hepatomegaly with no associated lymphadenopathy. The bone marrow showed haemophagocytosis and an infiltration of lymphoma cells. All patients showed increased levels of lactate dehydrogenase, C-reactive protein, ferritin and soluble interleukin-2 receptor. Lymphoma cells were positive for CD19. CD20 and surface immunoglobulin in all patients examined, and positive for CD5 in four of seven patients. Cytogenetic analyses of bone marrow cells showed a complex structural abnormality including chromosome 14q32 in two patients, 19q13 in three patients and deletion of the terminal part of 8p21 in six patients. The prognosis was poor; only two of the seven patients have survived in complete remission with a median survival of 11 months. These data suggested that B-cell lymphoma associated with HPS might constitute a distinct biological and clinical disease entity. Abnormality of chromosome 19q13 and loss of 8p21 might be involved in the pathogenesis of this disease.  相似文献   
154.
Lymph node metastasis determined by histologic examination is an important prognostic indicator in gastric carcinoma. However, prognostic value of lymph node metastasis detected by computed tomography (CT) is unknown. The aim of this study was to evaluate clinical results and prognostic factors of patients with radiologically node-positive gastric carcinoma. The study included 78 patients with primary gastric carcinoma and lymph node metastasis confirmed by CT. The level of lymph node metastasis was simply graded as follows: level I included perigastric nodes; level II included intermediate nodes along the left gastric, common hepatic, and celiac arteries; and level III included distant nodes along the hepatoduodenal ligament, pancreas, spleen, and abdominal aorta. Sixty patients (79%) had stage IV tumors showing one or more of the following: level III lymph node metastasis in 37, pancreatic invasion in 27, peritoneal dissemination in 23, and liver metastasis in 19. Overall 1- and 5-year survival rates were 29% and 6%, respectively, and the 1-year survival rate was significantly influenced by the level of lymph node metastasis on CT (55% for level I, 27% for level II, 7% for level III, P < 0.01). In patients with gastrectomy, prognostic factors were tumor size (<10 cm versus >10 cm, P < 0.01), gross type (localized versus infiltrative, P < 0.01), histologic type (well differentiated versus poorly differentiated, P < 0.01), and curability of the disease (curative versus noncurative, P < 0.01). Our study indicates that prognosis of patients with radiologically node-positive gastric carcinoma is poor because of high frequency of extensive tumor spreads. Patients having only positive level I nodes on CT are candidates for curative gastrectomy, which may offer long-term survival.  相似文献   
155.
156.
We have recently found that soluble form of receptor for advanced glycation end products (sRAGE) levels are positively associated with inflammatory biomarkers and the presence of coronary artery disease (CAD) in type 2 diabetic patients. Since advanced glycation end products (AGEs) up-regulate RAGE expression and endogenous sRAGE could be generated from the cleavage of cell surface RAGE, it is conceivable that sRAGE is positively associated with circulating AGEs levels in diabetes. In this study, we examined whether sRAGE were correlated to circulating levels of AGEs and soluble forms of vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) in patients with type 2 diabetes. Eighty-two Japanese type 2 diabetic patients underwent a complete history and physical examination, determination of blood chemistries, sRAGE, AGEs, sVCAM-1 and sICAM-1. Multiple regression analysis revealed that serum levels of AGEs and sVCAM-1 were independently correlated with sRAGE. This study demonstrated that serum levels of sRAGE were positively associated with circulating AGEs and sVCAM-1 levels in type 2 diabetic patients. Our present observations suggest sRAGE level may be elevated in response to circulating AGEs, thus being a novel marker of vascular injury in patients with type 2 diabetes.  相似文献   
157.
158.
BackgroundThe current understanding of ventilator efficiency variables during ramp exercise testing in the normal Japanese population is insufficient, and the responses of tidal volume (VT) and minute ventilation (V?E) to the ramp exercise test in the normal Japanese population are not known.MethodsA total of 529 healthy Japanese subjects aged 20–78 years underwent cardiopulmonary exercise testing using a cycle ergometer with ramp protocols. VT and V?E at rest, at anaerobic threshold, and at peak exercise were determined. The slope of V?E versus carbon dioxide (V?CO2) (V?E vs. V?CO2 slope), minimum V?E/V?CO2, and oxygen uptake efficiency slope (OUES) were determined.ResultsFor males and females in their 20 s, peak VT (VTpeak) was 2192 ± 376 and 1509 ± 260 mL (p < 0.001), peak V?E (V?Epeak) was 80.6 ± 18.7 and 57.7 ± 13.9 L/min (sex differences p < 0.001), the V?E vs. V?CO2 slope was 24.4 ± 3.2 and 25.7 ± 3.2 (p = 0.035), the minimum V?E/V?CO2 was 24.2 ± 2.3 and 27.0 ± 2.8 (p < 0.001), and the OUES was 2452 ± 519 and 1991 ± 315 (p < 0.001), respectively. VTpeak and V?Epeak decreased with age and increased with weight and height. The V?E vs. V?CO2 slope and minimum V?E/V?CO2 increased with age, while conversely, the OUES decreased with age.ConclusionsWe have established the normal range of VT and V?E responses, the V?E vs. V?CO2 slope, the minimum V?E/V?CO2, and the OUES for a healthy Japanese population. Some of these parameters were influenced by weight, height, sex, and age. These results provide useful reference values for interpreting the results of cardiopulmonary exercise testing in cardiac patients.  相似文献   
159.
TAFRO syndrome is a systemic inflammatory, lymphoproliferative disorder, but the pathophysiology of the disease is unknown. It is typically characterized by thrombocytopenia, anasarca, a fever, reticulin fibrosis, renal dysfunction, and organomegaly. However, other manifestations have been also reported. We encountered a 43-year-old man with TAFRO syndrome who showed mediastinal panniculitis, liver damage, and adrenal lesions in addition to the core signs. He achieved complete remission with combination therapy of corticosteroids, tocilizumab, and cyclosporin, and remission was maintained even after drug discontinuation at 15 months. Atypical manifestations and complete remission of TAFRO syndrome were remarkable features of our case.  相似文献   
160.
Though adult-onset primary autoimmune pancytopenia (AIP) rarely follows a self-limited course, a standard treatment strategy has not yet been established. We herein report two cases, each involving primary autoimmune neutropenia complicated with autoimmune thrombocytopenia or Evans syndrome. They were refractory to granulocyte-colony stimulating factor, but all lineages of cytopenia promptly recovered with prednisolone (PSL). In case 1, PSL was tapered and discontinued six months after its initiation without AIP relapse. In case 2, PSL has been tapered for five months without relapse. To establish an optimal treatment strategy for AIP, it is necessary to accumulate more cases.  相似文献   
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