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101.
BACKGROUND: Critical organ shortage in lung transplantation could be attenuated by the use of non-heart-beating donor (NHBD) lungs. In addition, prolonged ischemic tolerance of the organs would contribute to the alleviation of organ shortage. The aim of this study was to investigate pulmonary graft function of NHBD lungs after long-term hypothermic storage. METHODS: Twelve native-bred pigs (bodyweight 20 to 30 kg) underwent left lung allotransplantation. In the heart-beating donor (HBD) group, lungs were harvested immediately after cardiac arrest. In the NHBD group, lungs were subjected to a warm ischemic period of 90 minutes before harvesting. After a total ischemic time of 19 hours, pulmonary grafts in both groups were reperfused and pulmonary graft function was assessed. All values were compared with a sham-operated control group. RESULTS: Pulmonary graft function in the HBD group was excellent. In the NHBD group, pulmonary gas exchange was impaired, but still provided good graft function compared with the excellent graft function in the HBD group. Pulmonary vascular resistance was even lower in the NHBD group. In the NHBD group, calculated intrapulmonary shunt fraction (Qs/Qt) was significantly increased compared with the sham-group. Histologic alteration and wet-to-dry ratio did not differ significantly between the HBD and NHBD group. CONCLUSIONS: We conclude that NHBD lungs (90 minutes of warm ischemic time) have the potential to alleviate organ shortage in lung transplantation even after an extended total ischemic time.  相似文献   
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The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian-German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.  相似文献   
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OBJECTIVES: We sought to analyze the experience with bronchoplastic procedures over a 7-year period and to determine putative prognostic factors for survival. METHODS: From 1991 to 1997, 144 bronchoplastic procedures were performed for non-small cell lung cancer (n = 123), small cell lung cancer (n = 5), carcinoid tumor (n = 10), and metastases of extrathoracic malignant tumors (n = 6). There were 111 sleeve lobectomies, 17 bilobectomies, 4 lobectomies with carinal resection, 8 sleeve pneumonectomies, and 4 bronchotomies without parenchymal resection. Multivariable analysis included risk factors, such as age, sex, type of bronchoplastic procedure (bronchotomy, lobectomy, bilobectomy, or pneumonectomy), additional angioplasty, TNM staging, histology, radicality of resection, respiratory risk (forced expiratory volume in 1 second, percent predicted < 60), cardiovascular risk, and adjuvant therapy. RESULTS: Overall 1- and 3-year survival was 72% and 52%, respectively. The overall 30-day mortality was 8.3% (5.4% for single sleeve lobectomies). Multivariable analysis demonstrated 4 risk factors for survival. High tumor stage, type of bronchoplastic procedure, impaired lung function, and presence of cardiovascular risk were associated with a poor outcome. Univariate analysis showed reduced survival in patients with sleeve pneumonectomies (1-year survival, 25%). CONCLUSIONS: Bronchoplastic procedures for central tumors and sleeve pneumonectomies are associated with poor survival. Careful selection of these patients, as well as of patients with impaired lung function and cardiovascular risk factors, is mandatory.  相似文献   
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Interest in plant-based nutrition has steadily increased in the western world in the recent years. The number of people following a meat-reduced, flexitarian diet is growing continuously. However, little is known about the diet quality of flexitarians compared to vegans or omnivores. Therefore, in this cross-sectional study, the food intake of 94 participants aged between 25–45 years was recorded via a validated food frequency questionnaire and 28 self-designed questions about the consumption of plant-based alternatives. An adapted Healthy Eating Index, HEI-flex, was developed to evaluate the diet quality of flexitarians, vegans and omnivores. Higher score points (SP) of the HEI-flex are associated with higher compliance with the official diet recommendations (Vmax = 100 SP). Finally, flexitarians scored significantly more highly when compared to omnivores (54 ± 8 vs. 47 ± 9 SP; p = 0.008) but lower than vegans (54 ± 8 vs. 61 ± 10 SP; p = 0.010). The results showed that the HEI-flex is a useful tool for assessing and comparing the diet quality of flexitarians, vegans and omnivores. Despite the consumption of highly processed plant-based alternatives, reduction in meat and meat products seems to be accompanied by increased overall diet quality.  相似文献   
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In IgE-mediated food allergies, exposure to the allergen activates systemic allergic responses. Oral immunotherapy (OIT) treats food allergies through incremental increases in oral allergen exposure. However, OIT only induces sustained clinical tolerance and decreased basophil sensitivity in a subset of individuals despite increases in circulating allergen-specific IgG in all treated individuals. Therefore, we examined the allergen-specific antibodies from 2 OIT cohorts of patients with sustained and transient responses. Here, we compared antibodies from individuals with sustained or transient responses and discovered specific tolerance-associated conformational epitopes of the immunodominant allergen Ara h 2 recognized by neutralizing antibodies. First, we identified what we believe to be previously unknown conformational, intrahelical epitopes using x-ray crystallography with recombinant antibodies. We then identified epitopes only recognized in sustained tolerance. Finally, antibodies recognizing tolerance-associated epitopes effectively neutralized allergen to suppress IgE-mediated effector cell activation. Our results demonstrate the molecular basis of antibody-mediated protection in IgE-mediated food allergy, by defining how these antibodies disrupt IgE-allergen interactions to prevent allergic reactions. Our approach to studying the structural and functional basis for neutralizing antibodies demonstrates the clinical relevance of specific antibody clones in antibody-mediated tolerance. We anticipate that our findings will form the foundation for treatments of peanut allergy using neutralizing antibodies and hypoallergens.  相似文献   
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