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Antiphospholipid syndrome is a hypercoagulable disease that can present foot and ankle surgeons with a unique challenge in treating patients who present with thrombosis and ischemia despite having normal pedal pulses. Appropriate perioperative management is imperative in these patients, because limb- and life-threatening complications can occur postoperatively, despite aggressive anticoagulation. We present the case of a 46-year-old male who underwent a transmetatarsal amputation and, despite aggressive therapy, developed a myriad of complications postoperatively. At 10 months postoperatively, the patient was doing well in an accommodative orthotic with minimal pain while receiving continued aggressive therapy and follow-up examinations by a number of specialists to treat his antiphospholipid syndrome.  相似文献   
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Propofol, which is widely used as an intravenous anesthetic, has a phenolic structure similar to that of α‐tocopherol with antioxidant properties that could prevent genotoxicity and cytotoxicity in lymphocytes of anesthetized patients. The aims of this study were to evaluate oxidative DNA damage and apoptosis in lymphocytes and the expression of DNA repair genes in blood cells from patients undergoing elective surgery under anesthesia with propofol. Twenty healthy adults of both genders (18–50 years old) who were scheduled for otorhinological surgery were enrolled in this study. Blood samples were collected before anesthesia induction (T1‐baseline), 120 min after anesthesia induction (T2), and on the first postoperative day (T3). Oxidative DNA damage in peripheral lymphocytes was assessed using the comet assay. Lymphocytes were phenotyped as T helper or cytotoxic T cells, and apoptosis was evaluated using flow cytometry. The expression of DNA repair genes (hOGG1 and XRCC1) was assessed by quantitative polymerase chain reaction. A reduction in the level of oxidized purines in DNA (P < 0.01) was observed 120 min after anesthesia induction, and reduced apoptosis of T helper cells was observed 120 min after anesthesia induction and on the first postoperative day. Down‐regulation of hOGG1 and XRCC1 gene expression was observed on the first postoperative day. In conclusion, patients undergoing non‐invasive surgery under propofol anesthesia presented lower levels of oxidized purines and apoptosis of T helper lymphocytes. Furthermore, anesthesia with propofol did not directly influence the expression of the DNA repair genes hOGG1 and XRCC1 in blood cells. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc.  相似文献   
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Objectives

In patients with hypertrophic cardiomyopathy, obstruction of the left ventricular outflow tract can be relieved by surgical septal myectomy or alcohol septal ablation, but uncertainty remains regarding long-term results and comparative effectiveness of alcohol septal ablation. This study aims to compare short- and long-term outcomes of the 2 procedures.

Methods

Between December 1998 and September 2016, 2407 patients underwent septal myectomy and 211 patients underwent alcohol septal ablation at our institution. After 2:1 propensity score matching, the study cohort included 334 patients who underwent myectomy and 167 patients who underwent alcohol septal ablation.

Results

Median (interquartile range) ages of patients in the myectomy and alcohol septal ablation groups were 65 (58-71) years and 64 (56-73) years (P = .9), respectively. After intervention, median resting left ventricular outflow tract gradient at predischarge transthoracic echocardiography was 0 (0-10) mm Hg in the myectomy group (n = 288) and 21 (10-60) mm Hg in the alcohol septal ablation group (n = 63) (P < .001, tested at baseline gradients of 30 and 50 mm Hg). There were no differences in survival between the 2 groups (risk of death for alcohol septal ablation vs myectomy, hazard ratio, 1.5; 95% confidence interval, 0.9-2.6; P = .1). Survival of patients undergoing septal myectomy was better than that of an age-, sex-, and race-matched US population (82% vs 75% at 12 years, P = .01). Reintervention for left ventricular outflow tract obstruction was more likely to occur in patients who received alcohol septal ablation (hazard ratio, 33.3; 95% confidence interval, 4.4-250.6; P < .001).

Conclusions

There were no differences in survival of patients undergoing myectomy or alcohol septal ablation, but freedom from reintervention and early and late reduction of left ventricular outflow tract gradient are superior in patients undergoing septal myectomy.  相似文献   
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Measurement of the acoustic stapedial reflex parameters has proved to be a useful tool for evaluating the function of the acoustic-facial reflex. However, there is no agreement about the definitions of the parameters; moreover, most of the data have been obtained by manual measurement methods. The authors describe a computerized analytical method which permits the parameters to be measured according to the definitions and methods suggested by others and according to the new analytical method described, which is performed on the basis of the derivative of the stapedial reflex curve. The two methods are compared in 40 normal subjects.

La mesure des paramètres de la courbe de réponse du réflexe stapédien donne des renseignements pour l'évaluation de la fonction du réflexe acoustico-facial. II n'existe pourtant pas d'accord sur la définition des paramètres et la plupart des données ont été relevées manuellement. Dans ce travail les auteurs présentent un systeme d'analyse à l'aide d'un ordinateur qui permet de mesurer les paramètres du réflexe stapédien avec les méthodes généralement employées, d'après les définitions données par d'autres auteurs, et par une nouvelle méthode d'analyse, fondée sur l'étude de la dérivée de la courbe de réponse du réflexe. On décrit la nouvelle méthode d'analyse et on compare les résultats obtenus à l'aide des deux méthodes chez 40 sujets normaux.  相似文献   
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Infectious mononucleosis and B-cell transformation in response to infection with Epstein–Barr virus (EBV) is dependent upon binding of the EBV envelope glycoprotein gp350 to CD21 on B-cells. Gp350-specific antibody comprises most of the EBV neutralizing activity in the serum of infected patients, making this protein a promising target antigen for a prophylactic EBV vaccine. We describe a novel, tetrameric gp350-based vaccine that exhibits markedly enhanced immunogenicity relative to its monomeric counterpart. Plasmid DNA was constructed for synthesis, within transfected CHO cells, of a tetrameric, truncated (a.a. 1–470) gp350 protein (gp3501–470). Tetrameric gp3501–470 induced ∼20-fold higher serum titers of gp3501–470-specific IgG and >19-fold enhancements in neutralizing titers at the highest dose, and was >25-fold more immunogenic on a per-weight basis than monomeric gp3501–470. Further, epidermal immunization with plasmid DNA encoding gp3501–470 tetramer induced 8-fold higher serum titers of gp3501–470-specific IgG relative to monomer. Tetrameric gp3501–470 binding to human CD21 was >24-fold more efficient on a per-weight basis than monomer, but neither tetramer nor monomer mediated polyclonal human B-cell activation. Finally, the introduction of strong, universal tetanus toxoid (TT)-specific CD4+ T-cell epitopes into the tetrameric gp3501–470 had no effect on the gp3501–470-specific IgG response in naïve mice, and resulted in suppressed gp3501–470-specific IgG responses in TT-primed mice. Collectively, these data suggest that tetrameric gp3501–470 is a potentially promising candidate for testing as a prophylactic EBV vaccine, and that protein multimerization, using the approach described herein, is likely to be clinically relevant for enhancing the immunogenicity of other proteins of vaccine interest.  相似文献   
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