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After orthotopic heart transplantation (OHT), the allograft undergoes characteristic alterations in myocardial structure, including hypertrophy, increased ventricular stiffness, ischemia, and inflammation, all of which may decrease overall graft survival. Methods to quantify these phenotypes may clarify the pathophysiology of progressive graft dysfunction post-OHT. We performed cardiac magnetic resonance (CMR) with T1 mapping in 26 OHT recipients (mean age 47?±?7 years, 30?% female, median follow-up post-OHT 6 months) and 30 age-matched healthy volunteers (mean age 50.5?±?15 years; LVEF 63.5?±?7?%). OHT recipients had a normal left ventricular ejection fraction (LVEF 65.3?±?11?%) with higher LV mass relative to age-matched healthy volunteers (114?±?27 vs. 85.8?±?18 g; p?<?0.001). There was no late gadolinium enhancement in either group. Both myocardial extracellular volume fraction (ECV) and intracellular lifetime of water (τic), a measure of cardiomyocyte hypertrophy, were higher in patients post-OHT (ECV: 0.39?±?0.06 vs. 0.28?±?0.03, p?<?0.0001; τic: 0.12?±?0.08 vs. 0.08?±?0.03, p?<?0.001). ECV was associated with LV mass (r?=?0.74, p?<?0.001). In follow-up, OHT recipients with normal biopsies by pathology (ISHLT grade 0R) in the first year post-OHT exhibited a lower ECV relative to patients with any rejection ≥2R (0.35?±?0.02 for 0R vs. 0.45?±?0, p?<?0.001). Higher ECV but not LVEF was significantly associated with a reduced rejection-free survival. After OHT, markers of tissue remodeling by CMR (ECV and τic) are elevated and associated with myocardial hypertrophy. Interstitial myocardial remodeling (by ECV) is associated with cellular rejection. Further research on the impact of graft preservation and early immunosuppression on tissue-level remodeling of the allograft is necessary to delineate the clinical implications of these findings.  相似文献   
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Height has been associated with increased risk of fracture of the neck of femur. However, information on the association of height with fractures at other sites is limited and conflicting. A total of 796,081 postmenopausal women, who reported on health and lifestyle factors including a history of previous fractures and osteoporosis, were followed for 8 years for incident fracture at various sites by record linkage to National Health Service hospital admission data. Adjusted relative risks of fracture at different sites per 10‐cm increase in height were estimated using Cox regression. Numbers with site‐specific fractures were: humerus (3036 cases), radius and/or ulna (1775), wrist (9684), neck of femur (5734), femur (not neck) (713), patella (649), tibia and/or fibula (1811), ankle (5523), and clavicle/spine/rib (2174). The risk of fracture of the neck of femur increased with increasing height (relative risk [RR] = 1.48 per 10‐cm increase, 99% confidence interval [CI] 1.39–1.57) and the proportional increase in risk was significantly greater than for all other fracture sites (pheterogeneity < 0.001). For the other sites, fracture risk also increased with height (RR = 1.15 per 10 cm, CI 1.12–1.18), but there was only very weak evidence of a possible difference in risk between the sites (pheterogeneity = 0.03). In conclusion, taller women are at increased risk of fracture, especially of the neck of femur. © 2015 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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Relapse after autologous bone marrow transplantation for chronic myelogenous leukemia (CML) can be due either to the persistence of leukemia cells in systemic tissues following preparative therapy, or due to the persistence of leukemia cells in the autologous marrow used to restore marrow function after intensive therapy. To help distinguish between these two possible causes of relapse, we used safety-modified retroviruses, which contain the bacterial resistance gene NEO, to mark autologous marrow cells that had been collected from patients early in the phase of hematopoietic recovery after in vivo chemotherapy. The cells were then subjected to ex vivo CD34 selection following collection and 30% of the bone marrow were exposed to a safety-modified virus. This marrow was infused after delivery of systemic therapy, which consisted of total body irradiation (1,020 cGy), cyclophosphamide (120 mg/kg), and VP-16 (750 mg/m2). RT PCR assays specific for the bacterial NEO mRNA, which was coded for by the virus, and the bcr-abl mRNA showed that in two evaluable CML patients transplanted with marked cells, sufficient numbers of leukemia cells remained in the infused marrow to contribute to systemic relapse. In addition, both normal and leukemic cells positive for the retroviral transgenome persisted in the systemic circulation of the patients for at least 280 days posttransplant showing that the infused marrow was responsible for the return of hematopoiesis following the preparative therapy. This observation shows that it is possible to use a replication-incompetent safety-modified retrovirus in order to introduce DNA sequences into the hematopoietic cells of patients undergoing autologous bone marrow transplantation. Moreover, this data suggested that additional fractionation procedures will be necessary to reduce the probability of relapse after bone marrow transplantation in at least the advanced stages of the disease in CML patients undergoing autologous bone marrow transplantation procedures.  相似文献   
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IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.  相似文献   
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AIMS: Transient systolic and diastolic abnormalities in ventricular function have previously been documented during endurance sports. However, these described alterations may be limited by the techniques applied. We sought, using less load-dependent methods, to characterize both the extent and the chronology of the cardiac changes associated with endurance events. METHODS AND RESULTS: Transthoracic echocardiography (TTE) was performed prior to, immediately after, and approximately 1 month after completion of the 2003 Boston Marathon in 20 amateur athletes. TTE included two-dimensional, spectral and tissue Doppler (TD) and flow propagation velocity (V(p)). After completion of the marathon, global measures of left ventricular (LV) systolic function were unchanged (EF 59 +/- 6 vs. 61 +/- 4% post, P = 0.14), whereas TD-derived measures of LV systolic function [septal strain -23 +/- 5 vs. -17 +/- 4%, P = 0.007; septal strain rate (SR) -1.5 +/- 0.3 vs. -1.1+/- 0.2 s(-1), P = 0.007] and right ventricular (RV) systolic function (RV apical strain -33 +/- 4 vs. -27 +/- 5%, P = 0.001; RV apical SR -2.4 +/- 0.7 vs. -1.8 +/- 0.5, P = 0.002) were reduced. Significant changes in transmitral velocity (E/A ratio 2.0 +/- 0.5 vs.1.3 +/- 0.3, P = 0.005) and TD indices of LV and RV diastolic function (E(a) septal 9.5 +/- 1.8 vs. 8.1 +/- 1.2 cm/s post-marathon, P = 0.01) were also observed, indicating an inherent alteration in LV relaxation. Although all indices of LV and RV systolic function had returned to normal on follow-up, there were persistent diastolic abnormalities (RV E(a), 11.5 +/- 1.5 cm/s pre-marathon vs. 10.0 +/- 1.6 cm/s follow-up, P = 0.01). CONCLUSION: Marathon running leads to transient systolic and more persistent diastolic dysfunction of both the LV and the RV.  相似文献   
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Immune checkpoint inhibitors (ICIs) have been associated with neurological immune related adverse events (irAE-N) and patients with ICI toxicity may present with neurological or ocular symptoms. Furthermore, patients on ICI may initially present to oncology or neurology. We report a case series of 3 patients treated with ICIs presenting with diplopia or ptosis, found to have concurrent myocarditis in addition to immune-related myopathy (irMyopathy) or myasthenia gravis (irMG). None of the patients described cardiac symptoms, underscoring the importance of screening for myocarditis in patients presenting with diplopia and/or other neuromuscular symptoms which may suggest either irMyopathy or irMG.  相似文献   
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[Dmt(1)]DALDA (H-Dmt-D-Arg-Phe-Lys-NH(2)), is a highly potent and selective mu-opioid agonist. Nevertheless, systemic [Dmt(1)]DALDA retained its analgesic actions in MOR-1 knockout animals and CXBK mice despite the inactivity of morphine in these mice. [Dmt(1)]DALDA was 6-fold less potent in C57BL/6J mice than in CD-1 mice, whereas morphine potency did not differ between the two strains. Thus, [Dmt(1)]DALDA is a highly selective mu-opioid analgesic with significant pharmacological differences with the prototypic mu-opioid morphine.  相似文献   
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