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991.
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The Randomized Endo‐vein Graft Prospective (REGROUP) trial ( ClinicalTrials.gov  NCT01850082) is a randomized, intent‐to‐treat, 2‐arm, parallel‐design, multicenter study funded by the Cooperative Studies Program (CSP No. 588) of the US Department of Veterans Affairs. Cardiac surgeons at 16 Veterans Affairs (VA) medical centers with technical expertise in performing both endoscopic vein harvesting (EVH) and open vein harvesting (OVH) were recruited as the REGROUP surgeon participants. Subjects requiring elective or urgent coronary artery bypass grafting using cardiopulmonary bypass with use of ≥1 saphenous vein graft will be screened for enrollment using pre‐established inclusion/exclusion criteria. Enrolled subjects (planned N = 1150) will be randomized to 1 of the 2 arms (EVH or OVH) after an experienced vein harvester has been assigned. The primary outcomes measure is the rate of major adverse cardiac events (MACE), including death, myocardial infarction, or revascularization. Subject assessments will be performed at multiple times, including at baseline, intraoperatively, postoperatively, and at discharge (or 30 days after surgery, if still hospitalized). Assessment of leg‐wound complications will be completed at 6 weeks after surgery. Telephone follow‐ups will occur at 3‐month intervals after surgery until the participating sites are decommissioned after the trial's completion (approximately 4.5 years after the full study startup). To assess long‐term outcomes, centralized follow‐up of MACE for 2 additional years will be centrally performed using VA and non‐VA clinical and administrative databases. The primary MACE outcome will be compared between the 2 arms, EVH and OVH, at the end of the trial duration.  相似文献   
993.
Oxidative stress, apoptosis, and fibrosis may play a major role in the development of radiation‐induced liver damage. Betaine, a native compound widely present in beetroot, was reported to possess hepato‐protective properties. The objective of this study was to investigate the influence of betaine on radiation‐induced liver damage. Animals were exposed to 9 Gy applied in 3 doses of 3 Gy/wk. Betaine (400 mg/kg/d), was orally supplemented to rats after the first radiation dose, and daily during the irradiation period. Animals were sacrificed 1 day after the last dose of radiation. The results showed that irradiation has induced oxidative stress in the liver denoted by a significant elevation in malondialdehyde, protein carbonyl, and 8‐hydroxy‐2‐deoxyguanosine with a significant reduction in catalase activity and glutathione (GSH) content. The activity of the detoxification enzyme cytochrome P450 (CYP450) increased while GSH transferase (GSH‐T) decreased. The activity of the apoptotic marker caspase‐3 increased concomitant with increased hyaluronic acid, hydroxyproline, laminin (LN), and collagen IV. These alterations were associated with a significant increase of gamma‐glutamyl transferase, alkaline phosphatase and alanine and aspartate aminotransferase markers of liver dysfunction. Betaine treatment has significantly attenuated oxidative stress, decreased the activity of CYP450, enhanced GSH‐T, reduced the activity of caspase‐3, and the level of fibrotic markers concomitant with a significant improvement of liver function. In conclusion, betaine through its antioxidant activity and by enhancing liver detoxification and reducing apoptosis may alleviate the progression of liver fibrosis and exert a beneficial impact on radiation‐induced liver damage.  相似文献   
994.
Long-term granulocyte-colony stimulating factor treatment has been shown to be safe and effective in severe chronic neutropenia patients. However, data on its use during pregnancy are limited. To address this issue, we analyzed all pregnancies reported to the European branch of the Severe Chronic Neutropenia International Registry since 1994. A total of 38 pregnancies in 21 women with chronic neutropenia (16 pregnancies in 10 women with congenital, 10 in 6 women with cyclic, 12 in 5 women with idiopathic neutropenia) were reported. Granulocyte-colony stimulating factor was administered throughout pregnancy in 16 women and for at least one trimester in a further 5 women. No major differences were seen between treated and untreated women with respect to pregnancy outcome, newborn complications and infections. In addition, we evaluated the genetic transmission of known or suspected genetic defects in 16 mothers having 22 newborns as well as in 8 men fathering 15 children. As a proof of inheritance, neutropenia was passed on to the newborn in 58% from female and in 62% from male patients with ELANE mutations, but also to some newborns from parents with unknown gene mutation. Based on our results, granulocyte-colony stimulating factor therapy has been shown to be safe for mothers throughout pregnancies and for newborns without any signs of teratogenicity. With an increasing number of adult patients, genetic counseling prior to conception and supportive care of mothers during pregnancy are crucial. The acceptance of having affected children may reflect the high quality of life obtained due to this treatment.  相似文献   
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Venous thromboembolism (VTE) is prevalent and impactful, with a risk of death, morbidity and recurrence. Post-thrombotic syndrome (PTS) is a common consequence and associated with impaired quality of life (QoL). The ExACT study was a non-blinded, prospective, multicentred randomised controlled trial comparing extended versus limited duration anticoagulation following a first unprovoked VTE (proximal deep vein thrombosis or pulmonary embolism). Adults were eligible if they had completed ≥3 months anticoagulation (remaining anticoagulated). The primary outcome was time to first recurrent VTE from randomisation. The secondary outcomes included PTS severity, bleeding, QoL and D-dimers. Two-hundred and eighty-one patients were recruited, randomised and followed up for 24 months (mean age 63, male:female 2:1). There was a significant reduction in recurrent VTE for patients receiving extended anticoagulation [2·75 vs. 13·54 events/100 patient years, adjusted hazard ratio (aHR) 0·20 (95% confidence interval (CI): 0·09 to 0·46, P < 0·001)] with a non-significant increase in major bleeding [3·54 vs. 1·18 events/100 patient years, aHR 2·99 (95% CI: 0·81–11·05, P = 0·10)]. Outcomes of PTS and QoL were no different between groups. D-dimer results (on anticoagulation) did not predict VTE recurrence. In conclusion, extended anticoagulation reduced VTE recurrence but did not reduce PTS or improve QoL and was associated with a non-significant increase in bleeding. Results also suggest very limited clinical utility of D-dimer testing on anticoagulated patients.  相似文献   
998.
Washing of red cells is sometimes performed to reduce allergic reactions due to contaminating plasma proteins or to reduce the concentration of potassium accumulating in the supernatant of red cells during storage as an alternative to transfusion of fresher red cells in patients at risk of hyperkalaemia. There are a variety of methods for washing red cells, and the laboratory data suggest that variables such as age of red cell before washing, washing method and solution, storage medium and length of storage time after washing can all effect the final red cell quality. Studies suggest that washing removes 90–95% plasma, but the proportion of units below 0·05 mg/dl IgA (equivalent to IgA deficient) is variable dependent upon methods used. Although potassium levels are reduced immediately following washing, the rate of leakage following subsequent storage is method-dependent, requiring careful consideration of shelf life if potassium reduction is the goal. Other markers of red cell quality such as haemolysis are negatively impacted by washing so a reduced shelf life compared to standard red cells is appropriate, especially following irradiation. Data from animal models and clinical studies on possible additional benefits of washing, such as reduced lung or kidney injury, are mixed, ranging from some benefit to some harm, and further studies are warranted.  相似文献   
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