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1.
Transient receptor potential canonical (TRPC) Ca2+-permeant channels, especially TRPC3, are increasingly implicated in cardiorenal diseases. We studied the possible role of fibroblast TRPC3 in the development of renal fibrosis. In vitro, a macromolecular complex formed by TRPC1/TRPC3/TRPC6 existed in isolated cultured rat renal fibroblasts. However, specific blockade of TRPC3 with the pharmacologic inhibitor pyr3 was sufficient to inhibit both angiotensin II- and 1-oleoyl-2-acetyl-sn-glycerol–induced Ca2+ entry in these cells, which was detected by fura-2 Ca2+ imaging. TRPC3 blockade or Ca2+ removal inhibited fibroblast proliferation and myofibroblast differentiation by suppressing the phosphorylation of extracellular signal-regulated kinase (ERK1/2). In addition, pyr3 inhibited fibrosis and inflammation-associated markers in a noncytotoxic manner. Furthermore, TRPC3 knockdown by siRNA confirmed these pharmacologic findings. In adult male Wistar rats or wild-type mice subjected to unilateral ureteral obstruction, TRPC3 expression increased in the fibroblasts of obstructed kidneys and was associated with increased Ca2+ entry, ERK1/2 phosphorylation, and fibroblast proliferation. Both TRPC3 blockade in rats and TRPC3 knockout in mice inhibited ERK1/2 phosphorylation and fibroblast activation as well as myofibroblast differentiation and extracellular matrix remodeling in obstructed kidneys, thus ameliorating tubulointerstitial damage and renal fibrosis. In conclusion, TRPC3 channels are present in renal fibroblasts and control fibroblast proliferation, differentiation, and activation through Ca2+-mediated ERK signaling. TRPC3 channels might constitute important therapeutic targets for improving renal remodeling in kidney disease.  相似文献   
2.
In bone tissue regeneration, certain polymer and calcium-phosphate-based composites have been reported to enhance some biological surface phenomena, facilitating osteoinduction. Although the crucial role of inorganic fillers in heterotopic bone formation by such materials has been shown, no reports have been published on the potential effects the polymer phase may have. The present work starts from the assumption that the polymer molecular weight regulates the fluid uptake, which determines the hydrolysis rate and the occurrence of biological surface processes. Here, two composites were prepared by extruding two different molecular weight l/d,l-lactide copolymers with calcium phosphate apatite. The lower molecular weight copolymer allowed larger fluid uptake in the composite thereof, which was correlated with a higher capacity to adsorb proteins in vitro. Further, the large fluid absorption led to a quicker composite degradation that generated rougher surfaces and enhanced ion release. Following intramuscular implantation in sheep, only the composite with the lower molecular weight polymer could induce heterotopic bone formation. Besides influencing the biological potential of composites, the molecular weight also regulated their viscoelastic behaviour under cyclic stresses. The results lead to the conclusion that designing biomaterials with appropriate physico-chemical characteristics is crucial for bone tissue regeneration in mechanical load-bearing sites.  相似文献   
3.
The aim of this pilot study was to exploit the graft-versus-tumor potential of allogeneic transplants while improving safety of the procedure. Twelve patients with advanced hematological malignancies and solid tumors underwent a low intensity conditioning regimen (fludarabine and cyclophosphamide) followed by an allogeneic peripheral blood stem cell transplantation. The median time to achieve an absolute neutrophil count of more than 0.5 x 10(9)/l and an untransfused platelet count of more than 20 x 10(9)/l was 15 and 14 days, respectively. The main extra-hematological toxicities were mucositis and infections. Acute graft-versus-host (GVHD) disease was experienced by 62% of evaluable patients (grade II/B or III/C 80%) responsive to steroids. Extensive chronic GVHD was observed in 62% of patients. Non-relapse transplant-related mortality by day +30 was observed in three patients (25%). Eight out of 12 patients were full donor chimeric by day +100. One patient showed a mixed chimerism at day +37 when he died from progressive disease. One patient was in complete remission (CR) before allogeneic transplantation, and after transplantation four patients achieved CR and four experienced progressive disease. Our study confirms that a low intensity conditioning regimen for allogeneic stem cell transplantation is feasible and effective in heavily pretreated patients.  相似文献   
4.
目的 研究抗高血压药物相关基因在中国汉族人群的分布.方法 采用基因芯片法对β1受体阻断剂、血管紧张素Ⅱ受体抑制剂、血管紧张素转换酶抑制剂相关的5个基因多态位点(CYP2C9*3、ADRB1、AGTR1、CYP2D6*10和ACE)进行检测分型,研究分析我国高血压患者和健康受试者基因型频率分布及高血压男性患者与女性患者的...  相似文献   
5.

Purpose

Ultrasound imaging is an effective approach for diagnosing breast cancer, but it is highly operator-dependent. Recent advances in computer-aided diagnosis have suggested that it can assist physicians in diagnosis. Definition of the region of interest before computer analysis is still needed. Since manual outlining of the tumor contour is tedious and time-consuming for a physician, developing an automatic segmentation method is important for clinical application.

Methods

The present paper represents a novel method to segment breast ultrasound images. It utilizes a combination of region-based active contour and neutrosophic theory to overcome the natural properties of ultrasound images including speckle noise and tissue-related textures. First, due to inherent speckle noise and low contrast of these images, we have utilized a non-local means filter and fuzzy logic method for denoising and image enhancement, respectively. This paper presents an improved weighted region-scalable active contour to segment breast ultrasound images using a new feature derived from neutrosophic theory.

Results

This method has been applied to 36 breast ultrasound images. It generates true-positive and false-positive results, and similarity of 95%, 6%, and 90%, respectively.

Conclusion

The purposed method indicates clear advantages over other conventional methods of active contour segmentation, i.e., region-scalable fitting energy and weighted region-scalable fitting energy.
  相似文献   
6.
INTRODUCTION AND OBJECTIVES: To evaluate the clinical characteristics and prognosis of heart failure (HF) development in patients hospitalized for acute myocardial infarction (AMI). PATIENTS AND METHOD: Between May 1990 and March 2000, 836 consecutive patients were admitted with a diagnosis of AMI within 24 h of symptom onset. HF was defined as the presence of rales and a third heart sound with gallop, and evidence of pulmonary congestion on chest x-ray. It was diagnosed in 263 subjects (31.5%). RESULTS: The mean age of patients with HF (group 1) was 63.4 (11.4) years compared with 59.9 (11.6) years in those without HF (group 2) (P<.01). There were differences between groups 1 and 2 in history of diabetes (36% vs 20%; P<.001) or previous HF (9.2% vs 1.1%; P<.001). The reperfusion strategy used in patients with Q-wave infarction, with or without HF, was primary angioplasty in 15% and 14%, respectively (P=.81), and thrombolytic agents in 28% and 37%, respectively (P=.013). Patients with HF were more likely to develop recurrent angina (26.8% vs 19.6%; P=.02), pericarditis (17.5% vs 6.3%; P<.001), and atrial fibrillation (12.3% vs 5.1%; P<.01). In-hospital mortality in groups 1 and 2 was 15.6% and 2.3% (P<.001), respectively, and 10-year survival was 10% and 30%, respectively (P<.001). The variables associated with mortality were: age (HR=1.022; P<.001), hyperglycemia (HR=1.748 per 1.0-g/L increase; P<.001), leukocytosis (HR=1.035 per 1000-cell/.L increase; P<.001), and HF (HR=1.308; P=.028). CONCLUSIONS: AMI is still frequently complicated by HF, which increases short- and long-term morbidity and mortality. Heart failure, age, hyperglycemia, and leukocytosis at admission were independent predictors of mortality during follow-up.  相似文献   
7.
Between November 2001 and September 2004, 80 patients aged 11 to 56 years (mean, 27.6 years) underwent the Ross operation. The mean preoperative New York Heart Association functional class was 2.37 +/- 0.72, and the mean ejection fraction was 52.8% +/- 16%. Aortic involvement included stenosis in 19 (24%) patients, regurgitation in 22 (28%), and both in 39 (49%). Root replacement was the technique used in all cases. The mean hospital stay was 5 days, and 74 patients (93%) were followed up for 4-48 months. Four-year actuarial survival rate was 96.25%. Postoperative echocardiography revealed no pulmonary autograft insufficiency in 50 patients (63%), trivial to mild insufficiency in 22 (28%), moderate insufficiency in 2 (3%), and severe insufficiency in one (1%). Two patients required autograft re-intervention. Postoperative echocardiography of the pulmonary homograft valve showed severe stenosis (peak gradient > 50 mm Hg) in 2 patients, and moderate stenosis (peak gradient 25-50 mm Hg) in one. The mean postoperative left ventricular ejection fraction was 51.4%. The Ross operation can be considered an elegant alternative to prosthetic valves in the treatment of aortic valve diseases in developing countries.  相似文献   
8.
Tuberculosis is a public health problem. The most common presentation is pulmonary disease. The diagnosis of any extrapulmonary forms are quite difficult. Clinical manifestations of gastrointestinal tuberculosis are non-specific and compatible with pathologies such as inflammatory bowel disease, advanced ovarian cancer, deep mycosis, yersinia infection and amebomas. Abdominal form is located at 6th place of the extrapulmonary forms, after lymphatic, genitourinary, osteoarticular, miliary and meningeal infections. Eventually, 25 to 75% of patients with abdominal tuberculosis will require surgery. These procedures should be limitated with the purpose to preserve small bowel. Resection should be limitated for complicated cases. The surgical indications include: Intestinal occlusion (15-60%), perforation (1-15%), abscesses and fistulas (2-30%) and hemorrhage (2%). CONCLUSIONS: In most of the cases, the diagnosis of peritoneal or intestinal tuberculosis is made during a laparoscopy or laparotomy even during surgery performed by different purposes. Excessive manipulation of the intraabdominal organs may produced unexpected bowel lesions, increasing morbidity and mortality. Medical treatment is highly effective in the resolution of moderate complications such as bowel obstruction. Resectional procedures should be reserved for complications like perforation, bleeding or stenosis non-suitable for stricturoplasty.  相似文献   
9.
Background The clinical determinants of increased cardiac troponin T (cTnT) in patients with acute cardiogenic pulmonary edema are not well defined, and the ability of this marker to predict long-term mortality has not yet been documented. Methods Eighty-four patients with acute cardiogenic pulmonary edema without acute myocardial infarction were prospectively enrolled. cTnT was measured in samples obtained 6 and 12 hours after admission. Results cTnT levels of 0.1 ng/mL or greater were found in 46 patients (55%). Thirty-two patients (38%) died during follow-up. The area under the receiver operating characteristic curve for cTnT was 0.70 and 0.69 at 6 and 12 hours (P = .47), and the cTnT cutoff value of 0.1 ng/mL was 66% and 69% sensitive and 63% and 71% specific, respectively, in predicting subsequent mortality. Patients were assigned to group 1 if they had cTnT lower than 0.1 ng/mL and to group 2 if they had cTnT levels of 0.1 ng/mL or greater. A history of coronary artery disease was present in 72% of group 2 versus 50% of group 1 patients (P = .04). Patients in group 2 were also older than those in group 1 (mean age, 68 years vs 61 years; P = .021). The 3-year survival in group 1 was 76% compared with 29% in group 2 (log-rank test, P < .001). In a Cox proportional hazards model, elevated cTnT emerged as the only prognostic marker of long-term mortality (risk ratio [RR] = 2.31; 95% CI, 1.011-5.280; P = .047). Conclusions A cTnT level of 0.1 ng/mL or greater was associated with poor long-term survival and emerged as a powerful independent predictor of mortality in patients with acute cardiogenic pulmonary edema. (Am Heart J 2002;143:814-20.)  相似文献   
10.
Immunoglobulin G fractions from patients with Lambert-Eaton myasthenic syndrome (LEMS), an autoimmune disease of neuromuscular transmission, immunoprecipitate 125I-labeled omega-conotoxin GVIA-labeled calcium channels solubilized from rat brain. A 58-kDa antigen was detected by probing Western blots of partially purified calcium channels with LEMS plasma and IgG and was shown to be the relevant antigen in omega-conotoxin receptor immunoprecipitation. Monoclonal antibody 1D12, produced by immunizing mice with synaptic membranes, has properties similar to these autoimmune IgGs in both immunoprecipitation and Western blotting assays. 1D12 antigen was purified by immunoaffinity chromatography and shown to bind LEMS IgG. The antigen was identified by screening a rat brain cDNA library with 1D12 and was found to have strong homology to the synaptic vesicle membrane protein synaptotagmin. Our results indicate therefore that these antibodies immunoprecipitate omega-conotoxin receptors by binding to synaptotagmin that is associated with calcium channels. We suggest that the interaction between synaptotagmin and the voltage-gated calcium channel plays a role in docking synaptic vesicles at the plasma membrane prior to rapid neurotransmitter release and that autoantibody binding to a synaptotagmin-calcium-channel complex may be involved in the etiology of LEMS.  相似文献   
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