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911.

Objective

The risk of rupture and dissection in ascending thoracic aortic aneurysms increases as the aortic diameter exceeds 5 cm. This study evaluates the clinical effectiveness of a specific algorithm based on size and symptoms for preemptive surgery to prevent complications.

Methods

A total of 781 patients with nondissecting ascending thoracic aortic aneurysms who presented electively for evaluation to our institution from 2011 to 2017 were triaged to surgery (n = 607, 77%) or medical observation (n = 181, 24%) based on a specific algorithm: surgery for large (>5 cm) or symptomatic aneurysms. A total of 309 of 781 patients did not undergo surgery. Of these, 128 (16%) had been triaged to prompt repair but did not undergo surgery for a variety of reasons (“surgery noncompliant and overwhelming comorbidities” group). Another 181 patients (24%) were triaged to medical management (“medical” group).

Results

In the “surgery noncompliant and overwhelming comorbidities” versus the “medical” group, mean aortic diameters were 5 ± 0.5 cm versus 4.45 ± 0.4 cm and aortic events (rupture/dissection) occurred in 17 patients (13.3%) versus 3 patients (1.7%), respectively (P < .001). Later elective surgeries (representing late compliance in the “surgery noncompliant and overwhelming comorbidities group” or onset of growth or symptoms in the “medical” group) were conducted in 21 patients (16.4%) versus 15 patients (8.3%) (P = .04), respectively. Death ensued in 20 patients (15.6%) versus 6 patients (3.3%) (P < .001), respectively. In the “surgery noncompliant and overwhelming comorbidities” group, 7 of 20 patients died of definite aortic causes compared with none in the “medical” group.

Conclusions

Patients with ascending thoracic aortic aneurysms who did not follow surgical recommendations experienced substantially worse outcomes compared with medically triaged candidates. The specific algorithm based on size and symptoms functioned effectively in the clinical setting, correctly identifying both at-risk and safe patients.  相似文献   
912.
913.
PurposeObesity is associated with peripheral neuropathy, which bariatric surgery may ameliorate. The aim of this study was to assess whether corneal confocal microscopy can show a change in corneal nerve morphology and keratocyte density in subjects with severe obesity after bariatric surgery.MethodsTwenty obese patients with diabetes (n = 13) and without diabetes (n = 7) underwent assessment of hemoglobin A1c (HbA1c), lipids, IL-6, highly sensitive C-reactive protein (hsCRP), and corneal confocal microscopy before and 12 months after bariatric surgery. Corneal nerve fiber density (CNFD), corneal nerve branch density (CNBD), corneal nerve fiber length (CNFL), and keratocyte density (KD) from the anterior, middle, and posterior stroma were quantified. Twenty-two controls underwent assessment at baseline only.ResultsCNFL (P < 0.001), CNBD (P < 0.05), and anterior (P < 0.001), middle (P < 0.001), and posterior (P < 0.001) keratocyte densities were significantly lower in obese patients compared to controls, and anterior keratocyte density (AKD) correlated with CNFL. Twelve months after bariatric surgery, there were significant improvements in body mass index (BMI; P < 0.001), HDL cholesterol (P < 0.05), hsCRP (P < 0.001), and IL-6 (P < 0.01). There were significant increases in CNFD (P < 0.05), CNBD (P < 0.05), CNFL (P < 0.05), and anterior (P < 0.05) and middle (P < 0.001) keratocyte densities. The increase in AKD correlated with a decrease in BMI (r = –0.55, P < 0.05) and triglycerides (r = –0.85, P < 0.001). There were no significant correlations between the change in keratocyte densities and corneal nerve fiber or other neuropathy measures.ConclusionsCorneal confocal microscopy demonstrates early small fiber damage and reduced keratocyte density in obese patients. Bariatric surgery leads to weight reduction and improvement in lipids and inflammation and an improvement in keratocyte density and corneal nerve regeneration.  相似文献   
914.
IntroductionNephrotoxicity remains a major long-standing concern for colistin, and it is critical to find agents that can prevent it. The present study aims to investigate the effect of vitamin E on the prevention of colistin-induced nephrotoxicity based on its antioxidant and free radical scavenging properties.MethodsA randomized clinical trial was designed for 52 patients taking colistin. These patients were categorized into two groups of equal size, receiving colistin or colistin plus vitamin E (α-Tocopherol). Vitamin E with doses of 400 units was administrated daily either orally or by a nasogastric tube if needed. The incidence of Acute Kidney Injury (AKI) and its duration was recorded based on RIFLE criteria.ResultsThe Incidence of AKI based on RIFLE criteria was 42.3% and 46.2% in intervention and control groups, respectively. The analysis showed no significant difference in the prevalence of AKI for the two groups (P = 0.78). There was no significant difference in the duration of AKI neither (P = 0.83).ConclusionAlthough vitamin E is a powerful biological antioxidant, the effects of Vitamin E prophylaxis on colistin-induced nephrotoxicity was not taken into consideration in this study.  相似文献   
915.
The discovery of stem cells and their potential abilities in self-renewal and differentiation has opened a new horizon in medicine. Scientists have found a small population of stem cells in some types of cancers with the same functions as normal stem cells. There are two models for tumor progression: clonal (stochastic) and cancer stem cell (CSCs) models. According to the first model, all transformed cells in the tumor have carcinogenic potential and are able to proliferate and produce the same cells. The latter model, which has received more attention recently, considers the role of CSCs in drug resistance and tumor metastasis. Following the model, researchers have found that targeting CSCs may be a promising way in cancer therapy. This review describes CSC characteristics in general, while also focusing on CSC properties in the context of pancreatic cancer.  相似文献   
916.
Ataxia telangiectasia (AT) is a rare autosomal recessive neurodegenerative disorder caused by a mutation in the ATM gene. An impaired immune response due to the gene mutation leads to an increased risk of infection and malignancy. We present a rare case of dermatofibrosarcoma protuberans arising in a patient with AT.  相似文献   
917.
918.
Recently, human platelet antigens (HPAs) polymorphisms are found to play a role in susceptibility to hepatitis C virus (HCV) infection and fibrosis progression. The aim of the current study was to evaluate the possible association between the HPAs polymorphisms with liver fibrosis progression in HCV patients. HPAs polymorphisms genotyping was performed in HCV patients (n = 71) by Sequence-specific primers-polymerase chain reaction. Fibrosis progression was evaluated using the Metavir scoring system and liver biopsy, and the patients were assigned to two groups, namely, G1 (n = 35) that included patients with F1 (portal fibrosis without septa) or F2 (few septa) and G2 (n = 36) that comprised patients with F3 (numerous septa) or F4 (cirrhosis). The data analyses were performed using Pearson's χ2 test. The genotype frequency of HPA-3ab was significantly higher in G1 patients than in G2 patients (P = 0.015). No statistically significant differences were found between the patient groups (G1 and G2) regarding the distributions of the allelic and genotypic frequencies of the HPA-1, -2, -4, -5, and -15 systems. Multivariate logistic regression showed an independent association between the genotype HPA-3aa/BB and severe fibrosis (F3-F4), when compared with genotype HPA-3ab, independent of the viral genotype, high alanine transaminase, sex, age, time of infection, diabetes, and high cholesterol as risk factors. The present study suggested that the HPA-3ab genotype could be noticed as a potential protecting factor against hepatic fibrosis. Therefore, the antigenic variation of integrins might be considered as a part of the coordinated inflammatory process involved in the progression of liver fibrosis.  相似文献   
919.
Metabolic Brain Disease - Stroke is devastating and a leading cause of morbidity and mortality worldwide. Cerebral ischemia-reperfusion and its subsequent reactive hyperemia lead to neuronal damage...  相似文献   
920.
Non-compaction of the left-ventricular myocardium is an extremely rare cardiomyopathy. The most common clinical manifestations are heart failure, ventricular arrhythmia, thromboembolism, and sudden cardiac death. The condition is diagnosed by two-dimensional echocardiography or magnetic resonance imaging. We report a rare case of a 55-year-old man with coexistence of left ventricular non compaction cardiomyopathy, significant coronary artery disease and massive thrombus formation within recesses in left ventricular cavity.  相似文献   
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