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1.
The Latin American population has a double way of immigration, one toward the United States by proximity and another toward Spain by sociocultural affinity. This population increase is affecting organ donation and transplantation in receiving countries.

Objective

To analyze the brain death (BD) concept knowledge in the Dominican Republic immigrant population in Florida (United States) and Spain.

Method

Population under study: Population born in the Dominican Republic, resident in Florida (United States) and in Spain. Inclusion criteria: Population older than 15 years stratified by age and sex. Assessment instrument: Donation attitude questionnaire PCID-DTO-Ríos. Fieldwork: Random selection based on stratification. Immigration support association collaboration in Florida and Spain was needed to locate potential respondents. Completion was anonymous and self-administered, with verbal consent.

Results

A total of 123 respondents, 57 residents in Spain and 66 in Florida, have been included in the study. The 27% (n = 33) of the respondents knowledgeable of the BD concept consider it the death of an individual. Of the remainder, 52% (n = 64) do not know about it, and the remaining 21% (n = 26) believe it does not mean the death of a patient. No differences were observed regarding migration countries (P > .05). There was no association of the BD concept with other psychosocial factors analyzed or with the attitude toward organ donation.

Conclusions

Knowledge of the BD concept among the Dominican immigrant population is similar in Spain and Florida, and, unlike most studies, there is no objective association with the attitude toward organ donation.  相似文献   
2.
We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range.  相似文献   
3.
Three-dimensional (3D) PET acquisition has the potential to reduce image noise but the advantage of 3D PET for studies outside the brain has not been well established. To compare the performance of 2-dimensional (2D) and 3D acquisition for whole-body (18)F-FDG applications, a series of patient studies were performed using a lutetium oxyorthosilicate (LSO)-based tomograph. METHODS: Comparative 2D and 3D images were acquired for 27 oncology patients using an LSO-based tomograph. Data acquisition (350-650 keV, 6 ns) started 99 +/- 12 min (mean +/- SD) after injection of 624 +/- 76 MBq (18)F-FDG. Bias caused by tracer redistribution and decay was eliminated by acquiring dynamic data over a single-bed position using a protocol that alternated between septa-in and septa-out modes (2D, 3D, 2D, 3D, 2D, 3D). Frames were combined to form 8 statistically independent sinograms: four 2D replicates (105 s) and four 3D replicates (90 s). The different frame durations in 2D and 3D compensated for the different number of overlapping bed positions required for an 85-cm whole-body study. Images were reconstructed with either 2D or fully 3D ordered-subsets expectation maximization (2 iterations and 8 subsets; 2D 6-mm gaussian, 3D 5- and 6-mm gaussian). Image target-to-background ratio was assessed by dividing the lesion maximum by the mean within a neighboring background region. Image noise was assessed by applying background regions of interest to the replicate images and calculating the within-patient coefficient of variation. RESULTS: The difference in target-to-background ratio between the 2D and 3D images, when they were filtered with 6-mm and 5-mm gaussian filters, respectively, was not highly statistically significant (P = 0.16). The mean ratio of 3D to 2D image values was 0.94 with 95% limits of agreement of 0.63-1.41. The within-patient coefficients of variation for the 2D and 3D images were 13% +/- 15% and 9% +/- 10%, respectively (P = 0.0005). CONCLUSION: Under conditions of matched target to-to-background ratios, the 3D mode was found to produce images with significantly less variability than the 2D mode. These data provide support for the use of 3D acquisition with LSO detectors to reduce scan times in whole-body (18)F-FDG applications.  相似文献   
4.
The purpose of this study is to determine the importance of two-dimensional echocardiography performed soon after admission to the coronary care unit to provide useful information concerning wall-motion abnormalities, and to detect and characterize left ventricular thrombi. A major goal is to identify a subgroup of patients with acute myocardial infarction who are at risk for systemic embolization; in this subgroup the benefits of anticoagulation treatment would theoretically outweigh the associated risks. We studied 7 consecutive male patients, age range from 32 to 60 years, with acute myocardial infarction. Five patients had antero-septal infarction, 1 anterolateral and another had anterior wall infarction. We performed two-dimensional echocardiography within the first week after admission. All patients had severe apical-wall-motion abnormalities (akinesis or dyskinesis) and left ventricular thrombi. All patients received anticoagulation therapy. Two-dimensional echocardiography, performed one month after the first study, showed that the thrombi had decreased in size in 6 patients and could not be visualized in 1 patient. The noninvasive nature of echocardiography allows serial evaluations of patients with known left ventricular thrombi and permits assessment of the effect of therapy.  相似文献   
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6.
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
7.
The study was undertaken to analyze the basal and metoclopramide-stimulated serum PRL levels in healthy parous women users (group 1, n = 12) and non-users (group 2, n = 12) of a TCu-380 IUD. All women had regular menses and were studied between days 18 to 22 of their cycle; none had lactated nor regularly ingested any type of medication during the last six months. After a 10-12 hour overnight fast, peripheral venous blood samples were obtained through an indwelling catheter at -30, -15 and 0 minutes and at 60, 90 and 120 minutes after oral metoclopramide (10 mg). There were no significant differences in serum PRL between both groups, in basal levels nor throughout the test, whether analyzing the mean values at each sampling time, the sum of PRL levels from 60-120 minutes, or the peak levels. No correlation was observed between PRL levels and any of the clinical or obstetric characteristics of the women in both groups. Serum progesterone was greater than or equal to 4.0 ng/ml in all women. Thus, the use of alpha TCu-380 IUD did not induce any significant changes in basal nor in stimulated serum PRL levels.  相似文献   
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10.
Cationic Lipid-Based Gene Delivery Systems: Pharmaceutical Perspectives   总被引:4,自引:0,他引:4  
Gene delivery systems are designed to control the location of administered therapeutic genes within a patient's body. Successful in vivo gene transfer may require (i) the condensation of plasmid and its protection from nuclease degradation, (ii) cellular interaction and internalization of condensed plasmid, (iii) escape of plasmid from endosomes (if endocytosis is involved), and (iv) plasmid entry into cell nuclei. Expression plasmids encoding a therapeutic protein can be, for instance, complexed with cationic liposomes or micelles in order to achieve effective in vivo gene transfer. A thorough knowledge of pharmaceutics and drug delivery, bio-engineering, as well as cell and molecular biology is required to design optimal systems for gene therapy. This mini-review provides a critical discussion on cationic lipid-based gene delivery systems and their possible uses as pharmaceuticals.  相似文献   
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