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Lambert‐Eaton myasthenic syndrome (LEMS) is characterized by muscle weakness, amyotrophy, easy fatigability, and depressed tendon reflexes. 3,4‐Diaminopyridine (3,4‐DAP) is the recommended therapy for the treatment of LEMS. However, estimations of 3,4‐DAP pharmacokinetics in human and animals, such as rats, are rarely reported because 3,4‐DAP is an orphan drug for the treatment of a very rare disease (LEMS). In particular, little is known about its tissue distribution. Therefore, the pharmacokinetics of 3,4‐DAP were studied, with particular focus on tissue distribution, in rats. After intravenous administration of 3,4‐DAP to rats, the half‐life of 3,4‐DAP was 15.9 ± 3.9 min and the volume of distribution at steady‐state was 2.8 ± 0.7 L/kg. The tissue‐to‐plasma partition coefficient (Kp) was high in the kidney, heart, and muscle. In addition, with increased steady state plasma concentration (Css), a tendency toward increased Kp was found in most tissues. In the muscle, a likely target region of 3,4‐DAP in LEMS patients, the Kp was higher than in the plasma. Furthermore, more than 68% of 3,4‐DAP was distributed to the muscle as determined by the ratio of 3,4‐DAP distribution calculated from the apparent volumes of distribution. Hence, 3,4‐DAP may provide for more effective and long‐lasting effects.  相似文献   
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Serum interleukin-15 concentration in patients with essential hypertension   总被引:3,自引:0,他引:3  
BACKGROUND: Interleukin (IL)-15 is one of the cytokines produced by neutrophils and monocytes/macrophages, and its expression is found immunohistochemically in inflammatory cells adjacent to vulnerable atherosclerotic plaques. However, the influence of systemic IL-15 on cardiovascular disease is still unclear. Therefore, we designed clinical investigations to clarify the relationship between cardiovascular complications and serum IL-15 levels. METHODS AND RESULTS: Three hundred ninety-nine patients with essential hypertension were analyzed. We divided the study subjects into the following three groups according to the modified World Health Organization-International Society of Hypertension classification of 1999: patients with no organ damage (n = 213), patients with mild organ damage (n = 128), and patients with severe organ damage (n = 58). We measured serum IL-15, highly sensitive C reactive protein, IL-6, soluble intercellular adhesion molecule, and soluble vascular cell adhesion molecule levels. Serum IL-15 concentration in patients with severe organ damage was significantly higher than that in those with no organ damage (P < .01) and those with mild organ damage (P < .01). Serum IL-15 concentration in patients with coronary artery disease or peripheral artery disease was significantly higher than that in those without coronary artery disease or peripheral artery disease. Moreover, serum IL-15 concentration in patients with lacunar infarction was significantly higher than that in those without lacunar infarction (P < .005). By multiple linear logistic regression analysis, serum IL-15 concentration was independently correlated with cardiovascular disease. CONCLUSIONS: These data suggest that a systemic inflammatory response involving IL-15 might be involved in the occurrence of cardiovascular disease in patients with essential hypertension.  相似文献   
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This paper examines a case of pleomorphic primitive neuroectodermal tumor (PNET) with glial and neuronal differentiation in a 7-year-old girl who was clinicopathologically reported with immunohistochemical and chromosomal analysis. Clinically, a highly aggressive behavior leading to early recurrence with cerebrospinal fluid seedings was characteristic despite total removal and chemoradiation therapy. Pathologically, severe pleomorphism was noted and large ganglioid cells were predominant.Immunohistochemically, the expression of low-molecular neurofilament was recognized in the surgical specimens and increased in the recurrence. Coexpression of vimentin and neurofilament/GFAP was recognized in the culture. Chromosomal analysis showed near-diploidy, but different karyotype from that PNETs previously reported. These findings suggested that PNETs with pleomorphism and differentiation into both glial and neuronal lineages may show aggressiveness and require more aggressive therapy.  相似文献   
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The intermediate state of HTLV-1 infection, often found in individuals dually infected with Strongyloides stercoralis (S. stercoralis) and HTLV-1, is assumed to be a preleukemic state of adult T-cell leukemia (ATL). To investigate the effects of S. stercoralis superinfection on the natural history of HTLV-1 infection, we characterized peripheral blood samples of these individuals in Okinawa, Japan, an endemic area for both HTLV-1 and S. stercoralis and we studied effects of the parasite antigen on T-cells. The dually infected individuals showed a significantly higher provirus load and an increase in CD4(+)25(+) T cell population, with a significant, positive correlation. This increase was attributable to polyclonal expansion of HTLV-1-infected cells, as demonstrated by inverse-long PCR analysis of the integration sites. S. stercoralis antigen activated the IL-2 promoter in reporter gene assays, induced production of IL-2 by PBMC in vitro, and supported growth of IL-2 dependent cell lines immortalized by HTLV-1 infection or the transduction of Tax. Taken collectively, these results indicate that S. stercoralis infection induces polyclonal expansion of HTLV-1-infected cells by activating the IL-2/IL-2R system in dually infected carriers, an event which may be a precipitating factor for ATL and inflammatory diseases.  相似文献   
38.
Both cell proliferation and cell death occur simultaneously in tumor tissue, and extent of tumor growth reflects the net balance of these events. We correlated cell proliferation, spontaneous cell death, and alterations in tumor suppressor proteins with one another and with survival of patients with primary astrocytic tumors. In 39 astrocytic tumor specimens (6 pilocytic astrocytomas, 14 fibrillary astrocytomas, 9 anaplastic astrocytomas, and 10 glioblastomas), we determined the MIB-1 labeling index, the apoptotic ratio according to nick end labeling with morphologic confirmation, the p53 labeling index, and the presence of p53 or PTEN mutations.MIB-1 labeling indices of pilocytic astrocytomas, fibrillary astrocytomas, anaplastic astrocytomas, and glioblastomas were 0.30±0.32; 1.84±1.87; 19.3±6.42; and 28.0±14.5 (mean±SD), respectively. Corresponding apoptotic ratios were 17.9±5.16; 3.96±3.57; 1.18±0.93; and 2.11± 1.60 (mean±SD). The apoptotic ratio in pilocytic astrocytomas was significantly higher than in other astrocytic tumors (fibrillary astrocytomas, p<0.05; anaplastic astrocytomas and glioblastomas, p<0.01). MIB-1 showed a significant negative correlation with apoptosis (p<0.01). MIB-1 and apoptosis showed significant negative and positive correlations with patient survival (p<0.01). Mutations of p53 and PTEN show no correlation with survival and apoptotic ratio.The apoptotic ratio can clearly distinguish pilocytic astrocytomas from other tumors, and this biological feature may reflect less aggressive growth of pilocytic astrocytomas.  相似文献   
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A 77-year-old man with a history of cerebral infarction was admitted to our hospital with chest oppression. Coronary angiography revealed 2-vessel disease involving left main trunk. Coronary artery bypass grafting to left anterior descending artery and obtuse marginal branch was scheduled, but the patient developed hemiparesis and the scheduled coronary artery bypass grafting was postponed by at least one month. Unfortunately, the patient complained of severe chest pain at midnight of the second day from the onset of the neurological deficits and went into cardiogenic shock. We performed off-pump coronary artery bypass grafting to left anterior descending artery on the 5th day from the onset of the neurological deficits. His postoperative course was uneventful. Off-pump coronary artery bypass grafting is appropriate as an alternative procedure for high-risk patients with recent neurological deficits.  相似文献   
40.
The effect of Daikenchuto (DKT), a traditional Japanese herbal medicine (Kampo medicine), and its constituents (ginger rhizome, ginseng root, rice gluten and Zanthoxylum fruit) on the memory formation process was examined in mice by means of a Morris water maze test. The administration of DKT [300–4000 mg/kg, administered orally (p.o.)] for 3 consecutive days dose-dependently shortened the time required by the mice to find the platform in the water maze test relative to the control. Among the four constituents of DKT, the extract of Zanthoxylum fruit (70 mg/kg, the dose equivalent to 4000 mg/kg DKT) administered p.o. for 3 consecutive days significantly promoted the memory and learning rate. The memory- and learning-enhancing effect was potently elicited by 5 mg/kg (p.o., 2 days) hydroxy-sanshool, the active component of the ethyl acetate fraction of Zanthoxylum fruit. In another series of experiments with the water maze test, the administration of scopolamine [1 mg/kg, intraperitoneally (i.p.)] for 3 consecutive days significantly prolonged the time needed by the mice to find the platform. The subsequent administration of DKT (4000 mg/kg, p.o.) for 3 consecutive days possessed an abatement effect on the scopolamine-induced dementia. The present results indicate that DKT and, more specifically, its constituent Zanthoxylum fruit and the active component of Zanthoxylum fruit, hydroxy-sanshool, all have a memory- and learning-enhancing effect and are probably associated with the release of acetylcholine from neuronal terminals in the brain.  相似文献   
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