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1.
Oxidative stress is implicated in the pathogenesis of various cardiovascular diseases. We have shown that in Wistar rats with a suprarenal aortic constriction (AC), pressure overload-induced transient perivascular inflammation (monocyte chemoattractant protein-1 [MCP-1] induction and macrophage accumulation) in the early phase is the determinant of reactive myocardial fibrosis and resultant diastolic dysfunction in the late phase. Thus, we investigated the role of reactive oxygen species production in cardiac remodeling in AC rats. Superoxide production and the footprint of lipid peroxidation were assessed using dihydroethidium staining and immunohistostaining against 4-hydroxy-2-nonenal (4-HNE), respectively. In sham rats, dihydroethidium and 4-HNE signals were scarcely found in the heart. At day 3, AC rats showed dihydroethidium signals mainly in the intramyocardial arterial wall, whereas modest 4-HNE staining was observed diffusely in the myocardium. These signals declined to lower levels by day 14 despite sustained hypertension. Chronic administration of a subdepressor dose of an angiotensin II type 1 receptor blocker candesartan reduced the pressure overload-induced dihydroethidium and 4-HNE signals at day 3. Moreover, candesartan decreased MCP-1 induction and macrophage infiltration at day 3 and prevented myocardial fibrosis at day 14, without affecting left ventricle and myocyte hypertrophy. In conclusion, acute pressure overload induced self-limited superoxide production mainly in the vascular wall. The reactive oxygen species production would contribute to the perivascular inflammation and subsequent myocardial fibrosis. Angiotensin II was suggested to have a pressure-independent effect on the reactive oxygen species production.  相似文献   
2.
A 75-year-old man was admitted to our hospital with the chief complaint of a choking feeling around the esophagus. Laboratory examinations revealed eosinophilia, and high levels of serum immunoglobulin (Ig) E. A computed tomography scan (CT) showed wall thickening of the esophagus and terminal ileum, and ascites around the liver. An endoscopic examination revealed mild mucosal edema in the esophagus, stomach, and small intestine. Biopsy specimens showed diffuse eosinophilic infiltration in the mucosa. We therefore diagnosed eosinophilic gastroenteritis. Oral prednisolone relieved clinical conditions and the CT image improved. This case was considered valuable, because there have been few reports of eosinophilic esophagitis in Japan.  相似文献   
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4.
We report herein the case of a 70-year-old man in whom a chest wall implantation of adenocarcinoma of the lung at the drainage tube site was found 4 months after a right lower lobectomy with mediastinal lymph node dissection had been performed for adenocarcinoma of the right lower lobe. The lesion was successfully treated by tumor extirpation. We believe that tumor seeding to the chest wall occurred at the time of thoracotomy. To prevent such tumor seeding, the pleural cavity should be washed out routinely with a massive volume of physiological saline solution prior to closure of the chest wall.  相似文献   
5.
The aim of this study is to develop a technical quality evaluation system of electroencephalogram (EEG) recording in order to acquire technically satisfactory EEG records, which may contribute to the accuracy improvement of EEG interpretation. In our developed system, the evaluation of EEG recording comprises the detection of technical artifacts and physiological status, which indicates the recording status objectively. In addition, the caution signals to users are generated in the system according to the undesired status detected. The information displayed to users includes the updated EEG records and instant evaluation results. Two examples of evaluation results are introduced in this paper, illustrating unsatisfactory records and artifact free records, respectively. The experimental results are proposed to verify the effectiveness of the technical quality evaluation of EEG recording. The implementation of the technical quality evaluation of EEG recording is helpful to acquire technically satisfactory EEG records, which may improve the accuracy of results in both the visual and the automatic EEG interpretation, and ease the laborious work of EEG technicians in the recording progress.  相似文献   
6.
We undertook an investigation in which flow cytometry was used to characterize immune cell populations in the decidua of first-trimester normal pregnancies, spontaneous abortions, and ectopic pregnancies in comparison to the nonpregnant endometrium to demonstrate how the proportions of immunocompetent cell populations at the fetomaternal interface are influenced by the presence and state of a fetoplacental allograft. No significant differences were found in the decidua of the different types of first-trimester pregnancy in the proportions of the CD45+, CD14+, CD3+, CD4+, CD8+, CD19+, CD3-/CD16+ and/or CD56+, CD3+/CD16+ and/or CD56+, CD4+/Leu-8+, CD4+/Leu-8-, CD8+/CD11b+, CD8+/CD11b-, and CD3+/HLA-DR- decidual leukocyte subsets. However, the percentage of decidual CD3+/HLA-DR+ cells, which are characteristic of activated T cells, was significantly higher in spontaneous abortions than in normal pregnancies (p less than 0.05). This suggests that the accumulation of decidual leukocytes may be regulated mainly by hormones and/or cytokines rather than by the presence and state of an intrauterine conceptus and that on/off-switching of activation of decidual T cells may be associated with successful maintenance of the implanted embryo.  相似文献   
7.
1. Single fast muscle fibres isolated from the semitendinosus muscles of the frog were locally activated by applying linearly rising current pulses to a pipette whose tip (diameter, 10-40 mu) was in contact with the fibre surface.2. In normal or choline-Ringer solution with 1.8 mM-Ca, the threshold depolarization for producing a just perceptible local contraction was nearly constant over a wide range of the duration of linearly rising currents (0.5-20 sec or more).3. If [Ca](o) was reduced to 0.25-0.1 mM, the threshold depolarization increased steeply with the increase in the duration of linearly rising currents, indicating a marked increase in the rate of an accommodation process in excitation-contraction coupling mechanism.4. In the low-Ca media, the threshold depolarization was observed to rise exponentially during the application of a linearly rising current of 3-10 sec duration, and to return exponentially to its initial value within 3-10 sec after the removal of the current.5. The marked accommodation in the low-Ca media was partially inhibited by the addition of Mg (5-10 mM), and completely eliminated in the presence of caffeine (1 mM), suggesting that the accommodation process may occur in the link between membrane depolarization and release of Ca from sarcoplasmic reticulum.6. Microscopic observation of local contractions in the low-Ca media indicated that the accommodative rise of threshold depolarization was most marked at the superficial layer of the fibre.7. From these results, it is suggested that the removal of bound Ca or some other kind of charged particle from the transverse tubular system or from its vicinity might be the cause of accommodation in excitation-contraction coupling.  相似文献   
8.
Sugi T  McIntyre JA 《Human reproduction (Oxford, England)》2003,18(7):1553-4; author reply 1554
Dear Sir, We read the recent article by Franklin and Kutteh (2002), concerningthe pregnancy outcomes of recurrent pregnancy loss (RPL) patientswho had normal obstetrical evaluations with the exception ofpositive antiphospholipid antibodies (aPL) findings. In theirreport distinctions were made between two groups of aPL positiveRPL patients with reference to their aPL specificities. Group1 patients had ‘the common’ aPL, anticardiolipin(aCL), or antiphosphatidylserine antibodies (aPS) and/or a lupusanticoagulant (LAC). For comparisons,  相似文献   
9.
The formation of endocardial endothelium in quail embryos was investigated using in vivo and in vitro systems. At stage 7+ (2 somite), the initial emergence of endothelial cells within the bilateral heart forming region (HFR) was detected in quail embryos by immunohistochemistry with QH-1 (an anti-quail endothelial cell marker) and confocal microscopy. We consistently observed more QH-1 positive cells in the right HFR than the left. At stage 8 (4 somite), the HFR, including QH-1 positive cells, were located in the splanchnic mesoderm after formation of the coelom. During stage 8, the HFR migrated along the margin of anterior intestinal portal in association with the endoderm. By stage 8+ (5 somite), the two HFR had fused at the midline and formed a plexus of QH-1 positive endothelial precursor cells. The definitive endocardium developed as a single, hollow, tube within this plexus. Posteriorly, QH-1 positive cells of the HFR established vascular-like connections with QH-1 positive cells that had formed outside (peripheral to) the HFR. During migration and subsequent determination, the precardiac mesoderm is continuously associated with the basement membrane of the anterior endoderm. To determine the role of endoderm on endocardial endothelial cell formation and development, precardiac mesoderm from stage 5 embryos, which does not express QH-1 antigen, was explanted onto the surface of collagen gels. When co-cultured with endoderm, the outgrowth of free cells from the mesoderm was much more extensive, many of which invaded the gel and expressed the QH-1 antigen; mesoderm cultured without endoderm did not seed nor express QH-1 antigen. These findings suggest that the segregation of endothelial and myocardial lineages may occur by an endoderm-mediated, mesenchymal formation.  相似文献   
10.
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