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941.
ObjectiveTo examine the association between concentrations of serum vitamin C, a contributive factor to prevention of cardiovascular disease and levels of hs-CRP, a risk factor for cardiovascular disease, in population-based samples of middle-aged men and women.DesignA cross-sectional study.Methods and resultsThe subjects were 778 men and 1404 women, aged 40–69 years, who participated in a cardiovascular risk survey in Kyowa, Ibaraki prefecture in 2002 as part of the Circulatory Risk in Communities Study (CIRCS). Inverse associations between serum vitamin C concentrations and hs-CRP levels were established for both men and women. Multivariable-adjusted mean values of hs-CRP for the lowest to highest quintiles of vitamin C levels were 0.75, 0.65, 0.61, 0.61 and 0.47 mg/L (P for trend <0.001) for men, and 0.56, 0.51, 0.49, 0.41 and 0.41 mg/L (P for trend <0.001) for women. The inverse association between vitamin C and hs-CRP was stronger for non-smoking men and women, non-overweight women and postmenopausal women.ConclusionsSerum vitamin C concentrations were found to be inversely associated with hs-CRP levels in both men and women, primarily among non-smokers, non-overweight women and postmenopausal women. The respective roles of serum vitamin C and hs-CRP levels in the development of cardiovascular disease thus warrant further investigation.  相似文献   
942.
We reported previously that the autologous administration of bone marrow-derived mesenchymal stem cells (BM-MSC) significantly attenuated myocardial dysfunction and injury in a rat model of acute myocarditis by stimulating angiogenesis and reducing inflammation. Because BM aspiration procedures are invasive and can yield low numbers of MSC after processing, we focused on fetal membranes (FMs) as an alternative source of MSC to provide a large number of cells. We investigated whether the allogeneic administration of FM-derived MSC (FM-MSC) attenuates myocardial injury and dysfunction in a rat myocarditis model. Experimental autoimmune myocarditis (EAM) was induced in male Lewis rats by injecting porcine cardiac myosin. Allogeneic FM-MSC obtained from major histocompatibility complex-mismatched ACI rats (5 × 105 cells/animal) were injected intravenously into Lewis rats one week after myosin administration. At day 21, severe cardiac inflammation and deterioration of cardiac function were observed. The allogeneic administration of FM-MSC significantly attenuated inflammatory cell infiltration and monocyte chemoattractant protein 1 expression in the myocardium and improved cardiac function. In a T-lymphocyte proliferation assay, the proliferative response of splenic T lymphocytes was significantly lower in cells obtained from FM-MSC-treated EAM rats that reacted to myosin than in cells obtained from vehicle-treated rats with EAM. T-lymphocyte activation was significantly reduced by coculture with FM-MSC. The allogeneic administration of FM-MSC attenuated myocardial dysfunction and inflammation, and the host cell-mediated immune response was attenuated in a rat model of acute myocarditis. These results suggest that allogeneic administration of FM-MSC might provide a new therapeutic strategy for the treatment of acute myocarditis.  相似文献   
943.
The rabbit corneal epithelium model (RCE model) was developed as a three-dimensional in vitro model to replace animal testing for the assessment of eye tolerance. In the model, a stratified culture of rabbit corneal epithelial cells is grown at the air–liquid interface on an amniotic membrane acting as a parabasal membrane. The alkaline exposure was restored each day in the presence of no irritants, although with the addition of SLS, which is a major irritant, the restoration of deficit was inhibited on the RCE model in a dose-dependent manner. The results of this test were comparable with those of the Draize test, and thus, this method using the RCE model may prove to be a useful and sensitive in vitro eye irritation test. The lauryl fatty chain derivatives, such as polyoxyethylene (9) lauryl ether (PLE), sodium polyoxyethylene (2) lauryl ether sulfate (SPLE), mono glyceryl laurate (MGL), and sodium N-lauroyl-l-glutaminate (SLG), which are widely used as surfactants for toiletry products and cosmetics, were evaluated for in vitro eye irritation potential using the RCE model. SLS, PLE, SPLE, MGL, and SLG inhibited 88.7%, 59.2%, 69.0%, 47.5%, and 15.7% of the restoration of deletion 24 h after treatment at a concentration of 0.05%. The IC50 (50% inhibitory concentration) values of SLS, PLE, SPLE, MGL, and SLG were 0.002%, 0.021%, 0.005%, 0.056%, and 0.448%, respectively. These results indicated that a functional group at the end of lauryl chain is an important factor for inhibiting the restoration of deletion using the RCE model.  相似文献   
944.
Objective  Exposure to polychlorinated biphenyls (PCBs) is considered to have culminated between 1950 and 1970 in Japan, and exposure through diet, the major exposure route, has decreased significantly over the last 10 years. The primary goal of the present study was to investigate the long-term trends and congener profiles of serum and dietary levels of PCBs using historical samples. Methods  Using banked samples collected in 1980, 1995, and 2003 surveys, we determined the daily intakes and serum concentrations of 13 PCB congeners (#74, #99, #118, #138, #146, #153, #156, #163, #164, #170, #180, #182, and #187) in women. Results  The total daily PCB intake [ng/day, geometric mean (geometric standard deviation)] decreased significantly from 523 (2.5) in 1980 to 63 (3.2) in 2003. The serum total PCB level (ng/g lipid) in women <40 years of age decreased significantly from 185 (1.8) in 1980 to 68 (1.8) in 2003. In contrast, the level in women >50 years of age increased significantly from 125 (1.7) in 1980 to 242 (1.7) in 2003. Specifically, the serum concentrations of hexa (#138, #146, #153, #156, #163, and #164) and hepta (#170, #180, #182, and #187) congeners increased significantly. A comparison of the serum PCB levels of women born from 1940 to 1953 revealed that their serum total PCB level was significantly higher in the 2003 survey [242 (1.7), n = 9] than in the 1995 [128 (2.0), n = 17] surveys. This increase in the total PCB level was attributable to increases in the hepta congener groups. Conclusion  Present results suggest a decreased rate of elimination of hepta congeners with aging in females, rather than a birth-generation phenomenon.  相似文献   
945.
946.
Translocation of inhaled ultrafine particles from the lungs into the blood may impair cardiovascular function. We administered ultrafine (20-nm) and fine (200-nm) gold colloid or fluorescein-labeled polystyrene particles to mice intratracheally and examined their localization in the lung and extrapulmonary organs. Fifteen minutes after instillation, dispersed and agglomerated 20-nm gold colloid particles were observed on the surface of endothelial cells, on the alveolar surface, in endocytotic vesicles of alveolar epithelial cells, and in the basement membrane of the lung. A small but noteworthy amount of gold was detected in the liver, kidney, spleen, and heart by inductively coupled plasma-mass spectrometry. After administration of 20- or 200-nm fluorescent particles, free particles were detected infrequently in blood vessels, on the endocardial surface, and in the kidney and liver only in the mice that received 20-nm particles, whereas phagocytes containing 20- or 200-nm particles were found in the extrapulmonary tissues. Fluorescent particle-laden alveolar macrophages administered intratracheally translocated from alveoli to extrapulmonary organs via the blood circulation. Thus, small amounts of ultrafine particles are transported across the alveolar wall into the blood circulation via endocytotic pathways, but particle-laden alveolar macrophages translocate both ultrafine and fine particles from the lungs to the extrapulmonary organs.  相似文献   
947.
948.
We herein present a case of unresectable giant hepatic hemangiomas with Kasabach-Merritt syndrome which was successfully treated by living donor liver transplantation using a left lobe graft. The patient was a 45-year-old woman who complained of abdominal distension. Two sessions of transarterial embolization were performed, but failed to reduce the size of the tumor. The hepatic tumors were thus judged untreatable and the only option for a cure was to offer living donor liver transplantation, because of the tumor size, its location, and the association with Kasabach-Merritt syndrome. A left lobe graft with the middle hepatic vein donated by her 47-year-old brother was transplanted under venovenous bypass. The postoperative course of the recipient was complicated by small-for-size graft syndrome, which developed after episodes of acute cellular rejection on postoperative day 8 and sepsis on day 31. The patient successfully recovered from the complications and was discharged on day 72, and she remains well at 10 months after transplantation. In conclusion, living donor liver transplantation was found to be an effective option for the treatment of a patient with unresectable giant hepatic hemangiomas complicated by Kasabach-Merritt syndrome.  相似文献   
949.
We experienced the case of a left ventricular-free wall rupture (LVFWR) following successful coronary intervention for acute myocardial infarction (AMI). A 73-year-old woman was hospitalized because of chest oppression that had been continuing for 8 days. She was diagnosed to have AMI, and percutaneous coronary intervention (PCI) was performed. PCI was successful. However, immediately following PCI, she developed electromechanical dissociation secondary to tamponade because of blow-out-type LVFWR. The perforation tear was initially closed by a direct suture, followed by reinforcement using bovine pericardium patches sealed with GRF glue. The patient died of irreversible brain damage on postoperative day 3, but no re-bleeding or aneurysmal dilatation was detected at autopsy.  相似文献   
950.
We performed successful surgery for lung cancer after confirming the anatomical abnormality of a tracheal bronchus by three-dimensional multidetector-row computed tomography (3D-MDCT) bronchography and angiography. Tracheal bronchus is unusual, and right upper lobectomy for lung cancer would rarely be performed in a patient with a tracheal bronchus. Most clinicians are unfamiliar with the anatomy of a right upper lobe that includes a tracheal bronchus. Preoperative 3D imaging of the tracheal bronchus and its related vessels familiarized us with the anatomy of this patient before the operation. Thus, we recommend preoperative 3DMDCT bronchography and angiography, especially for patients with a possible bronchial anomaly.  相似文献   
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