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BACKGROUND: Many cardiac transplant programs have liberalized donor eligibility criteria in an attempt to maximize donor supply and to accommodate increasing demand. Although many studies have evaluated the potential adverse effects of prolonged donor ischemic time (DIT) in adults undergoing cardiac transplantation, relatively few have focused specifically on pediatric recipients that include a substantial number of patients and long-term follow-up. The focus of this study was to examine the effect of extended DIT on mortality after pediatric heart transplantation. METHODS: We conducted a retrospective review of our pediatric cardiac transplant experience in the past 11 years, comparing patients who received allografts and had ischemic times >240 minutes with those who had ischemic times <240 minutes. RESULTS: A total of 129 pediatric patients (<19 years) underwent orthotopic heart transplantation, of whom 78 (60.5%) had DIT <240 minutes and 51 (39.5%) had DIT >240 minutes. We found no statistically significant difference in age, sex, race, height, weight, or donor age between the groups (p = not significant). Post-transplant survival at 1, 5, and 10 years was similar for both groups: 91.2%, 88.0%, and 85.2%, respectively, for patients with DIT <240 minutes vs 89.6%, 87.2%, and 79.8%, respectively, for patients with DIT >240 minutes (p = 0.433). Additionally, using Cox proportional hazard models, extended DIT >240 minutes was not a statistically significant independent predictor of post-transplant mortality (odds ratio, 0.655; 95% confidence interval, 0.518-0.972; p = 0.684; standard error = 0.468). CONCLUSION: Procurement of hearts from distant locations with associated extended DIT is justified in the setting of increased demand and a fixed donor population.  相似文献   
13.
There is a growing body of literature supporting the contribution of genetic variability to the mechanisms responsible for the adverse effects of antipsychotic medications particularly movement disorders and weight gain. Despite the current gap between research studies and the practical tools available to the clinician to identify such risks, it is hoped that in the foreseeable future, pharmacogenetics will become a critical aid to guide the development of personalized therapeutic regimes with fewer adverse effects. We provide a summary of two cases that are examples of using cytochrome P450 pharmacogenetics in an attempt to guide treatment in the context of recent literature concerning the role of pharmacogenetics in the manifestation of adverse effects of antipsychotic therapies. These examples and the review of recent literature on pharmacogenetics of antipsychotic adverse effects illustrate the potential for applying the principles of predictive, preventive, and personalized medicine to the therapy of psychotic disorders.  相似文献   
14.
The usual methods for prenatal diagnosis of beta-thalassemia and other hemoglobinopathies by assay of fetal blood erythrocytes are either complex (analysis of globin chains synthesis by carboxymethylcellulose chromatography) or only semiquantitative [isoelectric focusing of hemoglobin (Hb)]. To further simplify the diagnostic procedure and to obtain quantitative data, we measured the small concentrations of Hb A in fetal erythrocytes by using a high-pressure liquid chromatography (HPLC) instrument (DIAMAT-TM; Bio-Rad) equipped with the new column proposed for measuring Hb A2. We analyzed 212 uncontaminated fetal blood samples obtained by cordocentesis between the 18th and 22nd weeks of pregnancy, using the HPLC procedure, and compared the results with those obtained by the above-named methods. The Hb A values obtained ranged between 0% and 8.5%; they were less than or equal to 1.8% in 44 fetuses affected by homozygous beta-thalassemia and greater than 2.5% in 168 unaffected fetuses. The method was simple, rapid, and reproducible (CV 3.2%) and there was good correlation between Hb A concentrations determined by HPLC and the beta/gamma ratio determined by carboxymethylcellulose chromatography (r = 0.7687; P less than 0.0001). No false-negative or false-positive results were observed, and there was no overlap of values between affected and unaffected fetuses.  相似文献   
15.
OBJECTIVE: We tested a hypothesis on two patterns of anticipatory postural adjustments (APAs) in neck muscles, reciprocal and co-activation, that may be used in a task-specific way. We also explored possible relation of APAs in leg and trunk muscles to head stabilization. METHODS: Load perturbations (loading and unloading) were applied to the head, trunk, and head and trunk simultaneously using similar hand actions by standing persons. Electromyographic signals (EMGs) from 10 muscles were recorded. Shifts of the center of pressure and EMG indices were computed over typical time intervals for APA. RESULTS: Time-shifted (reciprocal) activation of neck flexor and extensor muscles during APAs was seen when perturbations were applied directly to the head. Simultaneous activation dominated when the perturbations were applied to the trunk. Minimal APAs were seen in the leg/trunk muscles during head perturbation tests. APAs during trunk perturbation were not different from those during trunk and head perturbation. CONCLUSIONS: The results confirm the existence of two different patterns of APAs in neck muscles. A time-shifted (reciprocal) pattern is more likely to be used in anticipation of a perturbation acting directly on the head. A simultaneous activation (co-activation) pattern is used when direction of head perturbation cannot be predicted with certainty. Leg/trunk APAs are unlikely to help stabilize head posture. SIGNIFICANCE: These results are important for better understanding of feed-forward mechanisms of the control of head posture with possible implications for neurological patients who suffer from impaired feed-forward postural control.  相似文献   
16.
Different polymeric nanoparticles were freeze-dried and the powders compared to determine the influence of the lipophilic core (Miglyol 810) or benzyl benzoate) and polymeric material (poly(epsilon-caprolactone) or Eudragit S90) on their drug content and morphology. Diclofenac, a non-steroidal anti-inflammatory drug, was used as a model. To characterize the products, a biological experiment based on the evaluation of the mucosal toxicity of diclofenac was conducted. Nanocapsule and nanosphere suspensions were prepared by nanoprecipitation and freeze-dried after the addition of colloidal silicon dioxide. The powders were examined under scanning electron microscopy (SEM) and gastrointestinal tolerance of products was evaluated in rats. Powders presented drug contents between 90.2+/-5.5 and 101.1+/-1.9% (HPLC). SEM analyzes showed non-spherical microparticles and, at higher magnifications, the micro-powder surface presented a homogeneous nanocovering. Regarding the gastrointestinal tolerance, with the exception of benzyl benzoate-loaded formulations, powders presented lesional indexes lower than the diclofenac salt solution. In contrast to the literature, nanocapsules can be dried by freeze-drying without leakage of drug or breaking the capsule wall.  相似文献   
17.
At first, the authors mention indications and way of placement of the Angelchik prosthesis. Then after a wide review of the literature, they describe the complications and results. Finally a case of penetration into the stomach of an Angelchik prosthesis is reported. It was favourably resolved by an operation.  相似文献   
18.
From a review of 131 children with arthrogryposis, we studied 18 patients with hip dislocations. Fourteen patients (10 unilateral, four bilateral) were treated by open reduction. Mean age at surgery was 9.7 months, and follow-up ranged from 9 to 245 months. Range of motion of patients treated by open reduction following the medial approach was greater than in those treated by anterolateral incision and greater than in bilateral cases treated by closed reduction. Acetabular development was satisfactory following the medial approach and there were no re-dislocations, but one hip developed avascular necrosis.  相似文献   
19.
C6, a Borrelia burgdorferi-derived peptide, is used as the antigen in the C6-Lyme disease diagnostic test. We assessed retrospectively whether a fourfold decrease or a decrease to a negative value in anti-C6 antibody titer is positively correlated with a positive response to treatment in a sample of culture-confirmed patients with either early localized (single erythema migrans [EM]; n = 93) or early disseminated (multiple EM; n = 27) disease. All of these patients had been treated with antibiotics and were free of disease within 6 to 12 months of follow-up. Results show that a serum specimen taken at this time was either C6 negative or had a ≥4-fold decrease in C6 antibody titer with respect to a specimen taken at baseline (or during the early convalescent period if the baseline specimen was C6 negative) for all of the multiple-EM patients (P < 0.0001) and in 89% of the single-EM patients (P < 0.0001). These results indicate that a decline in anti-C6 antibody titer coincides with effective antimicrobial therapy in patients with early localized or early disseminated Lyme borreliosis.  相似文献   
20.
We validated a commercial enzyme-linked immunosorbent assay for the detection of anti-CagA antibodies in Brazilian patients with Helicobacter pylori infection. The test presented high sensitivity (97.4%) and specificity (88.9%) when employed in patients without gastric carcinoma. However, in gastric carcinoma patients, the test was neither sensitive nor specific enough to detect cagA-positive H. pylori infection.  相似文献   
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