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991.
Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is a membrane protein that can support the binding, internalization, and proteolytic degradation of oxidized low-density lipoprotein. The LOX-1 expression increases in the neointima after balloon injury. To develop an efficient compound to inhibit LOX-1, we designed and synthesized a novel gene silencer pyrrole-imidazole (PI) polyamide targeting the rat LOX-1 gene promoter (PI polyamide to LOX-1) to the activator protein-1 binding site. We examined the effects of PI polyamide to LOX-1 on the LOX-1 promoter activity, the expression of LOX-1 mRNA and protein, and neointimal hyperplasia of the rat carotid artery after balloon injury. PI polyamide to LOX-1 significantly inhibited the rat LOX-1 promoter activity and decreased the expression of LOX-1 mRNA and protein. After balloon injury of the arteries, PI polyamide to LOX-1 was incubated for 10 minutes. Fluorescein isothiocyanate-labeled PI polyamide was distributed to almost all of the nuclei in the injured artery. PI polyamide to LOX-1 (100 microg) significantly inhibited the neointimal thickening by 58%. PI polyamide preserved the re-endothelialization in the injured artery. PI polyamide significantly inhibited the expression of LOX-1, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, and matrix metalloproteinase-9 mRNAs in the injured artery. The synthetic PI polyamide to LOX-1 decreased the expression of LOX-1 and inhibited neointimal hyperplasia after arterial injury. This novel gene silencer PI polyamide to LOX-1 is, therefore, considered to be a feasible agent for the treatment of in-stent restenosis.  相似文献   
992.
Cardiovascular accidents related to atherosclerosis are the leading cause of death among hemodialysis patients, which makes continuous monitoring of their cardiovascular status crucial. Recently, a handy device for monitoring the augmentation index (AIx) in the radial artery was introduced in Japan, enabling the use of the AIx in addition to pulse wave velocity (PWV) in the management of hemodialysis patients. In this study the AIx, PWV, abdominal aortic calcification index (ACI), and left ventricular mass index (LVMI) were serially assessed in 108 hemodialysis patients. The radial AIx was monitored using a newly introduced tonometer (HEM-9010AI), and the interrelationships among the measured parameters and their contributions to the risk of cardiovascular accidents were evaluated. The radial AIx was significantly higher in hemodialysis patients than in healthy subjects (N = 50) and was well correlated with risk markers such as LVMI (r = 0.30, P = 0.019) and ACI (r = 0.38, P < 0.001), but not with PWV. Multiregression analysis showed that radial AIx was also significantly associated with LVMI, ACI and blood pressure; PWV was associated with other parameters such as age, blood pressure, and ACI. The AIx and ACI were both significantly increased in patients with cardiovascular complications. Although PWV was strongly increased in the hemodialysis patients, it failed to discriminate between these subgroups of high-risk patients. The radial AIx is closely associated with aortic calcification, cardiac hypertrophy, and a history of cardiovascular accidents in hemodialysis patients, and could be a useful marker for management of these patients.  相似文献   
993.
Angiotensin II (Ang II) plays a pivotal role in cardiovascular remodeling leading to hypertension, myocardial infarction, and stroke. Pitavastatin, an HMG-CoA reductase inihibitor, is known to have pleiotropic actions against the development of cardiovascular remodeling. The objectives of this study were to clarify the beneficial effects as well as the mechanism of action of pitavastatin against Ang II-induced organ damage. C57BL6/J mice at 10 weeks of age were infused with Ang II for 2 weeks and were simultaneously administered pitavastatin or a vehicle. Pitavastatin treatment improved Ang II-induced left ventricular hypertrophy and diastolic dysfunction and attenuated enhancement of cardiac fibrosis, cardiomyocyte hypertrophy, coronary perivascular fibrosis, and medial thickening. Ang II-induced oxidative stress, cardiac TGFbeta-1 expression, and Smad 2/3 phosphorylation were all attenuated by pitavastatin treatment. Pitavastatin also reduced Ang II-induced cardiac remodeling and diastolic dysfunction in eNOS-/- mice as in wild-type mice. In eNOS-/- mice, the Ang II-induced cardiac oxidative stress and TGF-beta-Smad 2/3 signaling pathway were enhanced, and pitavastatin treatment attenuated the enhanced oxidative stress and the signaling pathway. Moreover, pitavastatin treatment reduced the high mortality rate and improved renal insufficiency in Ang II-treated eNOS-/- mice, with suppression of glomerular oxidative stress and TGF-beta-Smad 2/3 signaling pathway. In conclusion, pitavastatin exerts eNOS-independent protective actions against Ang II-induced cardiovascular remodeling and renal insufficiency through inhibition of the TGF-beta-Smad 2/3 signaling pathway by suppression of oxidative stress.  相似文献   
994.
BACKGROUND: Cyclosporine (CsA), Mycophenolate mofetil (MMF) and prednisolone (PSL) are widely used for the prevention of acute rejection after heart transplantation. Recently, the serum concentration - time curves (AUC) of CsA and MMF have been demonstrated to be precise predictors of acute rejection. METHODS AND RESULTS: Fourteen heart transplant patients were treated concomitantly with CsA, MMF, and PSL between May 1999 and November 2005 at the National Cardiovascular Center and of them 3 had acute rejection episodes [International Society for Heart & Lung Transplantation grade 3a]. Two patients (man in his 30 s; woman in her 40 s) had acute rejection with a mycophenolic acid (MPA) AUC(0-12 h) <30 microg x h x ml(-1) and low CsA AUC (AUC(0-4 h); 2,408 ng x h x ml-1, 1,735 ng x h x ml-1). However, 1 patient (man in his 30 s) with a high CsA AUC(0-4 h) (4,019 ng x h x ml-1) did not develop cardiac allograft rejection even if the MMF was temporarily stopped. These 3 patients were investigated to evaluate the relationship between acute rejection and pharmacokinetic parameters, including the CsA C0, C2, AUC(0-4 h) and MPA AUC(0-12 h). CONCLUSIONS: The findings suggest that a high CsA AUC(0-4 h) may prevent rejection of a cardiac allograft, even if MMF is stopped or drastically reduced.  相似文献   
995.
We reported the case of pulmonary alveolar hemorrhage caused by propylthiouracil (PTU) with severe respiratory failure and anemia, who improved with PTU discontinuance and steroid therapy. A 35-year-old woman presented with pyrexia, shortness of breath, and arthralgia. Her chest radiograph and CT showed diffuse ground-glass opacities, and her arterial blood gas analysis revealed severe respiratory failure. Laboratory results included a hemoglobin level of 5.2 g/dl, and a myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) level of 203 EU (normal range <9.0 EU). As bronchoalveolar lavage (BAL) fluid showed fresh blood-like fluid containing hemosiderin-laden macrophages, pulmonary alveolar hemorrhage was diagnosed. Since she had been taking PTU for 4 years, PTU was immediately discontinued. Steroid pulse therapy was performed, followed by oral prednisolone 30 mg per day, and her symptoms and chest radiograph findings rapidly improved. Based on the time-course changes, MPO-ANCA may have been involved in the development of pulmonary alveolar hemorrhage.  相似文献   
996.
Hypertension contributes to the occurrence and progression of cardiovascular diseases. The angiotensin II type 1 receptor blocker telmisartan is reported to activate the peroxisome proliferator-activated receptor gamma and improve insulin sensitivity. We investigated the effects of telmisartan treatment on visceral fat, serum adiponectin and vascular inflammation markers in Japanese hypertensive patients. This was an open-label, non-controlled study. Twenty-eight essential hypertensive patients (22 men and 6 women; age 60.6+/-1.9 years; body mass index [BMI] 25.5+/-0.6 kg/m(2)) participated. Fat area was assessed with computerized tomography. All the subjects were started on telmisartan 40 mg/day, which was increased to 80 mg/day to achieve the blood pressure target of less than 130/80 mmHg. We assessed the visceral and subcutaneous fat areas, serum adiponectin levels, and vascular inflammation markers at baseline and 24 weeks of telmisartan treatment. There were significant reductions in visceral fat area (from 103.1+/-7.9 to 93.3+/-8.4 cm(2), p<0.01) and pulse wave velocity (from 1,706+/-52 to 1,587+/-51 cm/s, p<0.01) at 24 weeks. In contrast, significant increases in serum high-density lipoprotein cholesterol (from 5.06+/-0.15 to 5.32+/-0.13 mmol/L, p<0.05) and adiponectin levels (from 8.27+/-0.76 to 9.13+/-0.81 microg/mL, p<0.05) were observed. Also, there were reductions in the interleukin-6 level (from 2.26+/-0.27 to 1.60+/-0.14 pg/mL, p<0.01). We also conducted these investigations in male subjects alone and similar findings were obtained for all of these parameters. In conclusion, telmisartan treatment was associated with an improvement of vascular inflammation, reductions in visceral fat and increases in serum adiponectin.  相似文献   
997.
BACKGROUND AND AIM: The health-related quality of life (HRQOL) of patients with ulcerative colitis (UC) can be impaired because of the chronic symptoms. Although UC patients suffer from such symptoms over the long term, there have been few reports on the changes of HRQOL with disease duration. The aim of this study was to clarify these changes. METHODS: The HRQOL of 331 Japanese UC patients was examined using the validated Japanese version of the Inflammatory Bowel Disease Questionnaire (J-IBDQ). HRQOL and factors affecting HRQOL identified using multiple linear regression analysis were stratified by disease duration. RESULTS: Of the 15 clinical factors examined, the clinical activity index score was the strongest determinant (P<0.0001) of all the scores of IBDQ regardless of disease duration. HRQOL did not differ significantly among patients with different disease durations. The factors, however, that affected HRQOL varied according to disease duration. In patients with disease duration of less than 5 years, the clinical activity index score was the predominant factor affecting HRQOL. Being 'on sick leave or hospitalized' was a significant factor impairing HRQOL in patients with disease duration of 5-9 years. Moreover, complications due to corticosteroids significantly impaired all of the IBDQ scores in patients with disease duration of 10 years or more. CONCLUSION: Factors that affected the HRQOL of UC patients varied according to the patients' disease duration. Our findings should assist in the development of a long-term strategy for the treatment of UC patients.  相似文献   
998.
BACKGROUND: Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE: Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN: Case series. SETTING AND PATIENTS: A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION: ESD. MAIN OUTCOME MEASUREMENTS: En bloc resection rate, complete resection rate, operation time, and complications. RESULTS: En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION: Short duration of follow-up. CONCLUSIONS: ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists.  相似文献   
999.
1000.
Background: The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments.

Methods: This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension.

Results: Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = ?0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p < 0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022).

Conclusion: Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.  相似文献   

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