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71.

Background

Transcatheter mitral valve replacement (TMVR) is a potential therapy for patients with symptomatic, severe mitral regurgitation (MR). The feasibility of this therapy remains to be defined.

Objectives

The authors report their early experience with TMVR using a new valve system.

Methods

The valve is a self-expanding, nitinol valve with bovine pericardial leaflets that is placed using a transapical delivery system. Patients with symptomatic MR who were deemed high or extreme risk by the local heart teams were enrolled in a global pilot study at 14 sites (United States, Australia, and Europe).

Results

Fifty consecutively enrolled patients (mean age: 73 ± 9 years; 58.0% men; 84% secondary MR) underwent TMVR with the valve. The mean Society for Thoracic Surgery score was 6.4 ± 5.5%; 86% of patients were New York Heart Association functional class III or IV, and the mean left ventricular ejection fraction was 43 ± 12%. Device implant was successful in 48 patients with a median deployment time of 14 min (interquartile range: 12 to 17 min). The 30-day mortality was 14%, with no disabling strokes, or repeat interventions. Median follow-up was 173 days (interquartile range: 54 to 342 days). At latest follow-up, echocardiography confirmed mild or no residual MR in all patients who received implants. Improvements in symptom class (79% in New York Heart Association functional class I or II at follow-up; p < 0.0001 vs. baseline) and Minnesota Heart Failure Questionnaire scores (56.2 ± 26.8 vs. 31.7 ± 22.1; p = 0.011) were observed.

Conclusions

TMVR with the valve was feasible in a study group at high or extreme risk for conventional mitral valve replacement. These results inform trial design of TMVR in lower-risk patients with severe mitral valve regurgitation (Evaluation of the Safety and Performance of the Twelve Intrepid Transcatheter Mitral Valve Replacement System in High Risk Patients with Severe, Symptomatic Mitral Regurgitation – The Twelve Intrepid TMVR Pilot Study; NCT02322840)  相似文献   
72.
Pericardial patch has been used to repair cardiac defects; however, its strength as an aortoplasty patch to tolerate systemic pressure is a matter of debate. We report an aneurysmal dilatation of pericardial patch in aortoplasty. Our patient was a 56-year-old female known case of rheumatic heart disease that underwent redoes mitral and aortic valve replacements along with Manouguian aortoplasty at the age of 44?years old. After 2?months, she was readmitted with a diagnosis of endocarditis. Echocardiography revealed a small cavity in the posterior wall of the aorta. She responded to medical therapy and discharged in a good condition. Twelve years later, she was scheduled to undergo reoperation due to a severe paraprosthetic aortic valve leakage and a pericardial patch aneurysm. The leaking prosthetic aortic valve was explanted and the aneurysmal tissue was replaced with a polyethylene terephthalate patch.  相似文献   
73.
BACKGROUND/AIMS: Few reports have analyzed short- and long-term outcomes in the subset of patients with hepatocellular carcinoma (HCC) on non-cirrhotic liver. METHODOLOGY: From January 1985 to December 2002, 277 patients underwent liver resection for HCC; in only 47 the liver was normal or showed mild chronic hepatitis at histology. RESULTS: A major hepatectomy (MHR) was accomplished in 37 cases (78.7%) including an extended hepatic resection in 18 (38.3%). In-hospital mortality was nil. The rate of complications was 40.4%. Overall and disease-free survival rates at 5 years were 30.9% and 33.9%. Fifteen patients are actually alive with a median survival of 33.3 months. By multivariate analysis, tumor size > 10cm and presence of satellite nodules were independent predictive factors of 5-year survival; median survival of thirteen patients with HCCs < or = 10cm and without daughter nodules was 60 months. Twenty-six patients had a margin less than 1cm and without cancer involvement; overall and recurrence-free survival rates were comparable to those of the patients with a > 1cm margin. CONCLUSIONS: In the treatment of HCC without cirrhosis, major hepatic resections are often needed. Tumors less than 10cm in size and without satellite nodes are the best candidates for operation. The width of the resection margin is unimportant provided that there is no microscopic infiltration.  相似文献   
74.
A 49-year-old man presented with a 3-week history of vomiting and diarrhea. He reported foamy stools but no blood or melena and had crampy epigastric pain. He denied usage of antibiotics. He had been taking ranitidine for intermittent epigastric pain for the last few months and noted an 11-pound weight loss during the 3 weeks before admission. Stool was positive for Clostridium difficile toxin and Giardia lamblia antigen. Cultures and occult blood tests were negative. Oral metronidazole, 500 mg 3 times a day, was administered, and the patient was hydrated. The diarrhea resolved, and patient was discharged on the fourth hospital day. Prior antibiotic therapy is the most common risk factor for C difficile colitis. This patient developed concomitant infection with C difficile and G lamblia while he used ranitidine. He had no other risk factors for these infections. Hence, we propose that ranitidine-induced hypochlorhydria predisposed this patient to the enteric infections.  相似文献   
75.
Background: SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is recognized for the first time in Wuhan, China. The cytokine storm is a known factor causing major clinical symptoms leading to death in COVID-19 patients. Objective: To investigate and compare the serum levels of different cytokines in COVID-19 patients with different clinical severity. Methods: Concentrations of serum cytokines, including IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, TNF-α, IFN-γ, and GM-CSF, were measured in 61 COVID-19 patients and 31 normal controls with ELISA. We investigated the correlation between the levels of these cytokines and clinical severity, CRP level, neutrophil and lymphocyte count in patients with COVID-19. Results: Our data indicated that the levels of IL-1β, IL-2, IL-4, IL-6, IL-8, TNF-α, IFN-γ, and GM-CSF, but not IL-10 were significantly increased in COVID-19 patients compared to normal controls. Statistical analysis showed that the level of IL-1β, IL-2, IL-4, IL-6, IL-8, TNF-α, IFN-γ, and GM-CSF were higher in severe COVID-19 than those of mild cases. The concentrations of all mentioned cytokines were negatively associated with the absolute count of lymphocytes, and positively correlated with the CRP level and the absolute count of neutrophils. Conclusion: The current study suggests that high levels of various cytokines correlate with the disease severity and immunopathogenesis of COVID-19.  相似文献   
76.
77.

Background

The remineralization of early caries lesion has an effective role on decreasing caries. For initial remineralization of caries lesion, using Compounds of Casein phosphopeptides (CPP) in different studies has been proposed. REMINPRO including Fluoride, Xylitol and Calcium phosphate has just been offered in the market. This study aims to investigate the efficacy of Reminpro and MI paste plus in terms of remineralization of early enamel lesions.

Materials and methods

In 15 samples of healthy enamels of the maxillary first premolar teeth and 15 samples of Primary Mandibular First Molar under the effect of demineralized gel, artificial caries has been created. The samples have been divided in 3 groups of 20. After performing the cycles of demineralization and remineralization during 5 weeks, the samples were investigated by DIAGNOdent and two samples from each group were compared with SEM. To investigate the remineralization of enamel, two-way ANOVA and to compare the groups in pair, the post hoc tests were used.

Results

The mean of mineralization of teeth in the group using reminpro was 25.2 ± 6.16 and in the group using MI paste plus was 23 ± 5.60, which was significantly high.

Conclusions

MI paste plus in mineralization of initial enamel caries were more efficient that reminpro pate.  相似文献   
78.
Tissue‐engineered dermal substitutes represent a promising approach to improve wound healing and provide more sufficient regeneration, compared with current clinical standards on care of large wounds, early excision, and grafting of autografts. However, inadequate regenerative capacity, impaired regeneration/degradation profile, and high cost of current commercial tissue‐engineered dermal regeneration templates hinder their utilization, and the development of an efficient and cost‐effective tissue‐engineered dermal substitute remains a challenge. Inspired from our previously reported data on a pullulan/gelatin scaffold, here we present a new generation of a porous pullulan/gelatin scaffold (PG2) served as a dermal substitute with enhanced chemical and structural characteristics. PG2 shows excellent biocompatibility (viability, migration, and proliferation), assessed by in vitro incorporation of human dermal fibroblasts in comparison with the Integra® dermal regeneration template (Control). When applied on a mouse full‐thickness excisional wound, PG2 shows rapid scaffold degradation, more granulation tissue, more collagen deposition, and more cellularity in comparison with Control at 20 days post surgery. The faster degradation is likely due to the enhanced recruitment of inflammatory macrophages to the scaffold from the wound bed, and that leads to earlier maturation of granulation tissue with less myofibroblastic cells. Collectively, our data reveal PG2's characteristics as an applicable dermal substitute with excellent dermal regeneration, which may attenuate scar formation.  相似文献   
79.

Purpose

The objective is to study mammography practice from an optimisation point of view by assessing the impact of simple and immediately implementable corrective actions on image quality.

Materials and methods

This prospective multinational study included 54 mammography units in 17 countries. More than 21,000 mammography images were evaluated using a three-level image quality scoring system. Following initial assessment, appropriate corrective actions were implemented and image quality was re-assessed in 24 units.

Results

The fraction of images that were considered acceptable without any remark in the first phase (before the implementation of corrective actions) was 70% and 75% for cranio-caudal and medio-lateral oblique projections, respectively. The main causes for poor image quality before corrective actions were related to film processing, damaged or scratched image receptors, or film-screen combinations that are not spectrally matched, inappropriate radiographic techniques and lack of training. Average glandular dose to a standard breast was 1.5 mGy (mean and range 0.59–3.2 mGy). After optimisation the frequency of poor quality images decreased, but the relative contributions of the various causes remained similar. Image quality improvements following appropriate corrective actions were up to 50 percentage points in some facilities.

Conclusions

Poor image quality is a major source of unnecessary radiation dose to the breast. An increased awareness of good quality mammograms is of particular importance for countries that are moving towards introduction of population-based screening programmes. The study demonstrated how simple and low-cost measures can be a valuable tool in improving of image quality in mammography.  相似文献   
80.
AIM: To investigate the associations of hepatitis B virus (HBV) genotype with HBeAg and anti-HBe status, alanine aminotransferase (ALT) levels and HBV-DNA detection in different groups of HBV-infected patients in southwest Iran. METHODS: A total of 89 HBsAg-positive serum samples were collected from the same number of patients. All sera were then investigated to determine HBV DNA and serological markers. For all the polymerase chain reaction (PCR)-positive samples, biochemical, histopathological assays and genotyping were also performed. RESULTS: Genotype D was the only type of HBV foundin different clinical forms of acute and chronic infections. There was a high prevalence of HBeAg-negative HBV- infected patients with chronic hepatitis (52.7%). Out of 55 patients with chronic hepatitis, seven (12.7%) were diagnosed with cirrhosis. A significant association between the presence of anti-HBe antibody and an increase in ALT level, among either HBeAg-negative (P = 0.01) or HBeAg-positive (P = 0.026) patients, was demonstrated. No significant differences were observed between the clinical outcomes of HBeAg-positive and -negative individuals (P = 0.24). CONCLUSION: Genotype D has been recognized as the only type of HBV found in different clinical forms of HBV infections, including cirrhosis, among the residents of southwest Iran. Anti-HBe possibly plays a role in disease progression in some patients with chronic hepatitis, at least for a period of disease.  相似文献   
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