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11.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop.  相似文献   
12.
Recently, a self‐expandable metallic stent has been recognized for treatment of malignant duodenal stenosis. But the complications by stenting are important problems even now. In the present study, we report our new method of duodenal stenting by using of double‐balloon enteroscopy considered safe and effective.  相似文献   
13.
Abstract Uro-neurological assessment was performed in four patients with small-fiber neuropathy due to amyloidosis (2 transthyretin-type/2 immunoglobulin light-chain-type). Voiding difficulties were due to detrusor weakness and impaired bladder sensation. In two patients cholinesterase inhibition treatment caused urge incontinence, indicating detrusor denervation supersensitivity. The underlying mechanisms of urinary dysfunction seem to involve postganglionic cholinergic and afferent somatic nerves.  相似文献   
14.
Abstract A study was conducted to elucidate the mechanism of donor-pecific Mixed Lymphocyte Reaction (MLR and Cell Mediated Lymphotoxicity (CML) unresponsiveness in a renal transplant recipient with a long-term well-functioning kidney. The peripheral blood lymphocytes (PBL) of the recipient, who had not shown rejection since his transplantation 5 years previously, and those of his mother (donor), his father and two healthy third parties were examined. MLR, CML, semimicro MLR in a double chamber, interleukin-2 (IL-2) synthesis assay and limiting dilution assay were performed. This recipient showed donor-pecific MLR and CML unresponsiveness. IL-2 assay showed that the PBL of the recipient produced less IL-2 against the donor than against the father and the third parties. The addition of exogenous recombinant IL-2 (rIL-2; Takeda Co.) to the priming MLR caused a recovery of CML against the donor. A limiting dilution assay indicated that cytotoxic T cell precursor (CTLp) frequencies against the donor and father did not differ. The suppressor assay in a double chamber indicated that the PBL of the recipient stimulated by the donor PBL had a non-pecific suppressive effect on MLR, CML and IL-2 synthesis of the PBL across the Major Histocompatibility Complex (MHC) barrier. This suppressive effect was abolished by OKT3 or OKT8 monoclonal antibody and complement. Thus, the recipient had donor-pecific suppressor T cells that produced a humoral non-pecific suppressive factor only when stimulated by the donor PBL, and this factor suppressed PLR and CML by inhibiting IL-2 synthesis of the PBL.  相似文献   
15.
A statistical 30-year study of dermatomycosis in Sendai National Hospital (1968-1997) revealed many changes in the prevalent diseases: Tinea pedis and tinea unguium constantly increased during this period, and the ratio of the former associated with nail infection finally reached 30% of all tinea pedis patients. On the contrary, tinea corporis and cruris showed a remarkable decreasing tendency. Patient age distribution of each disease also showed distinctive changes, generally increasing in the older generation and decreasing in the younger. The number of patients with tinea pedis and unguium gradually increased among the middle and older generations, with the peak of the age-distribution curve shifting upward year after year. On the other hand, cases of tinea cruris among the younger generation were few in the latest years, and middle-age patients remained at a low number. In the first stage of this study the kinds of atiologic dermatophytes consisted of multiple species, but after middle period the isolation of Epidermaphyton floccosum decreased. Microsporum canis appeared first in 1976 but in the recent several years has completely disappeared. In the last few years of the period studied Trichophyton rubrum and Trichophyton mentagrophytes were the only isolates found from among all types of dermatophytoses. Infantile candidiasis remarkably increased in 1970-1975 but thereafter decreased rapidlly. Candidial intertrigo also increased in the same period but did not decrease as much thereafter and continued at the same intermediate level. The number of other types of candidiases were not greatly changed throughout the 30-year period. Malassezia infection also showed no remarkable changes, and only 20 cases of sporothrichosis were found. One case of the deep seated form of cutaneous aspergillosis was found, and this was also true of chromomycosis caused by Fonceaea pedrosoi.  相似文献   
16.
OBJECTIVE: We present a case of spontaneous ovarian hyperstimulation caused by pituitary gonadotroph macroadenoma, and include a review of the literature. CASE REPORT: A 27-year-old woman presented with irregular menstruation and bilateral multicystic enlargement of the ovaries. Serum estradiol (E(2)) levels were marginally elevated for the follicular phase but within the physiological range. Serum luteinizing hormone (LH) was extremely low, follicle-stimulating hormone (FSH) was normal, and prolactin (PRL) was high. Magnetic resonance imaging disclosed a pituitary macroadenoma. Immunohistochemical examination of the surgically removed adenoma showed intense reactivity for FSH and LH. After the operation, E(2), LH and PRL levels were normalized, the ovaries returned to a normal morphology, and regular menstrual cycles were resumed. CONCLUSION: A review of the literature showed that ovarian hyperstimulation caused by pituitary gonadotroph adenoma is not always accompanied by elevated FSH levels. High PRL and E(2) and low LH were reported in the majority of the cases, but E(2) may stay within the range observed in normal menstrual cycles.  相似文献   
17.
OBJECTIVE: The risk of stroke caused by dislodgment of loose atheromatous plaque or mural emboli is increased by cross-clamping of the aorta. Some patients undergo descending thoracic aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. The objective of this study was to determine the influence of proximal aortic cross-clamping in arteriosclerotic aneurysm or dissecting aneurysm repair. METHODS: Between May 1984 and May 2003, 81 patients underwent elective surgery for distal arch or descending aortic aneurysm repair with proximal aortic cross-clamping between the left common carotid artery and the left subclavian artery. To evaluate the influence of the proximal aortic cross-clamping, patients were divided into two groups: patients who had undergone arteriosclerotic aneurysm repair (group I, n=25) and patients who had undergone dissecting aneurysm repair (group II, n=56). RESULTS: Eight (9.9%) of the 81 patients had a stroke. Six strokes occurred in operations for arteriosclerotic aneurysm repair group I and two strokes occurred in operations for dissecting aneurysm repair group II (24 vs 3.6%; p=0.009). In-hospital mortality rates were 12% in group I and 8.9% in group II (p=0.70). Major postoperative complications included renal failure requiring hemodialysis (in 4.2% of the patients in group I and in 8.3% of the patients in group II, p=0.99) and pulmonary complication (in 20% of the patients in group I and in 16% of the patients in group II, p=0.67). CONCLUSION: Cross-clamping between head vessels should be avoided if at all possible when operating on patients who have arteriosclerotic descending thoracic aneurysms.  相似文献   
18.
Although the glucocorticoid receptor (GR) facilitates the xenobiotic-induced expression of CYP2B in rodents, its role in the regulation of human CYP2B6 is unclear. In this report, the role of human GR in the regulation of CYP2B6 was evaluated using primary human hepatocytes and transfection assays with Huh7 cells. CYP2B6 expression was not induced in primary hepatocytes treated with dexamethasone (DEX) concentrations (0.01-1 microM) known to activate GR. In contrast, treatment with 0.1 microM DEX enhanced CYP2B6 induction by different pregnane X receptor (PXR) activators, including rifampin, phenytoin, clotrimazole, and phenobarbital. In Huh7 cells, cotransfection of human (h)GR and hPXR with CYP2B6-phenobarbital-responsive enhancer module (PBREM) reporter constructs revealed that all hPXR ligands induce CYP2B6 reporter gene activity, and this ligand-dependent activation is greatly enhanced by activated hGR. CYP2B6 reporter gene expression was not induced in the presence of hPXR ligands when hGR alone was cotransfected with CYP2B6 reporter construct. In hGR and human constitutive androstane receptor (hCAR) cotransfection assays, activated hGR increased the constitutive activation of PBREM reporter constructs by hCAR in the absence of inducers. In the presence of activated hGR and known inducers of CYP2B6, only PB treatment caused a further 2-fold activation of hCAR compared with control. These studies show that hGR is involved synergistically in the xenobiotic-responsive regulation of human CYP2B6 by hPXR and hCAR. Moreover, the results suggest that the GR-enhanced expression of CYP2B6 is mediated through an indirect mechanism that does not require increased expression of nuclear receptor.  相似文献   
19.
Early gastric cancer manifested as brain metastasis: Report of a case   总被引:1,自引:0,他引:1  
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis.  相似文献   
20.
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