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71.
Because death with a functioning graft remains one of the most important causes of long-term renal transplant failure, cardiac risk stratification and screening for coronary artery disease are essential components of pretransplant assessment. Pretransplant screening for occult coronary artery disease in a subset of these patients may improve outcome. The UK follows the European Best practice guideline 1.5.5 E. Although echocardiography, thallium myocardial perfusion scanning (MPS), dobutamine stress echocardiography, and coronary angiography have been suggested as means of cardiovascular assessment, the best means of assessment remains undetermined. Therefore, we investigated the role of 99m technetium sestamibi myocardial perfusion scanning as an assessment tool for identifying those patients with end-stage renal failure at high risk of cardiovascular death after renal transplantation. Retrospectively, we studied 126 patients that had a MPS as part of their pretransplant assessment. Overall unadjusted survival was 65% at 3 years. Twelve deaths resulted from cardiovascular causes. A reversible defect on MPS was associated with a fatal cardiac event and all-cause mortality. The unadjusted hazard ratio of cardiac event with reversible defect on MPS was 3.1 (95% confidence interval, 1.1 to 18.2) and hazard ratio of death with reversible defect on MPS was 1.92 (95% confidence interval, 1.1 to 4.4). Thus, MPS may be a useful tool in cardiac risk stratification and in selecting patients with a favorable outcome after renal transplantation. Our patients with a reversible defect in particular have increased cardiac mortality. This group may benefit from coronary angiography. 相似文献
72.
Harper SJ Hosgood SA Waller HL Yang B Kay MD Goncalves I Nicholson ML 《Transplantation》2008,86(3):445-451
BACKGROUND: The precise effect of warm ischemia on renal allograft function remains unclear and leads to variable warm ischemic time (WIT) limits advocated by transplant programs. This study aims to investigate the relationship between WIT, renal ischemia reperfusion injury, and graft function using a hemoperfused kidney model. METHODS: Porcine kidneys were perfused with normothermic blood on an isolated organ perfusion system. Kidneys were divided into four groups (n=6) and subjected to 7, 15, 25, and 40 min WIT. Physiological parameters were measured throughout the 6 hr perfusion period. Serum, tissue, and urine samples were analyzed for histological and biochemical markers of ischemia reperfusion injury. RESULTS: Creatinine clearance, urine output, renal hemodynamics, and oxygen consumption deteriorated proportionally with increasing WIT. A significant increase in plasma carbonyl levels during perfusion was seen after 25 and 40 min WIT only. Plasma 8-isoprostane levels were higher after 40 min WIT (2.5+/-1.6) vs. 7, 15, and 25 min WIT (0.65+/-0.43, 0.25+/-0.12, and 0.62+/-0.21, respectively; P<0.05). A negative correlation was shown between urine output and plasma carbonyls (r=-0.415, P<0.05) and between 8-isoprostane levels and creatinine clearance (r=-0.649, P<0.005). Caspase-3 activity was significantly higher after 7 min WIT compared with the other groups, correlating positively with creatinine clearance, urine output, and renal blood flow. CONCLUSION: The isolated organ perfusion system successfully delineated a clear WIT-dependent variation in renal function which correlated accurately with oxidative injury markers. This model may represent a clinically applicable tool for assessing graft viability. 相似文献
73.
Carol DeMatteo James R Bain Deborah Gjertsen Jessica A Harper 《CANADIAN JOURNAL OF PLASTIC SURGERY》2014,22(3):183-187
BACKGROUND:
Obstetrical brachial plexus injury (OBPI) in children can cause great distress to a family due to uncertain recovery, variability in spontaneous recovery and unclear indicators for surgery.OBJECTIVE:
To investigate the impact of having a child with OBPI on the family and whether the Impact on Family Scale (IoFS) can assist in addressing family concerns.METHODS:
A mixed-method (cross-sectional survey and semistructured interviews) study design was used.RESULTS:
Thirty-eight families of children with OBPI completed the IoFS. Surgery significantly predicted a higher IoFS total impact score (P=0.02). No statistically significant association between the total impact score and severity or age was found, suggesting that impact on family was not dependent on these factors. Themes that emerged from the interviews included traumatic birthing experience, wondering and waiting, and experiencing surgery.CONCLUSION:
All families should receive support and acknowledgement of the widespread impact of OBPI. 相似文献74.
Sperm preparation techniques in assisted reproduction technologies (ART) are potential generators of exogenous stresses that cause additional DNA damage. DNA fragmentation tests, such as the sperm chromatin structure assay, involve freezing sperm samples in the absence of cryoprotectant. Thermal, oxidative stress (OS) and freezing are detrimental to sperm DNA fragmentation and phosphatidylserine (PS) translocation. The primary aim of this study was to subject mature sperm to environmental insults that normally occur during ART. We tested the hypotheses that OS, thermal stress and freeze‐thawing caused sperm nuclear and membrane damage and that a positive correlation exists between PS translocation and DNA fragmentation. Sperm DNA integrity deteriorates in semen samples from men with advancing age and a sperm concentration of <15 m ml?1. The significant increase in sperm DNA fragmentation at 37 °C after merely 1 h is important clinically as semen liquefaction and short‐term sperm storage in an ART cycle involve incubating samples at this temperature. Freezing without a cryoprotectant significantly increases the level of sperm nuclear damage, so it is important not to freeze neat semen prior to DNA fragmentation testing. This study highlights the importance of minimising the production of exogenous stresses during sperm preparation in ART. 相似文献
75.
Chris J. Callaghan Simon J.F. Harper Kourosh Saeb‐Parsy Alex Hudson Paul Gibbs Christopher J.E. Watson Raaj K. Praseedom Andrew J. Butler Gavin J. Pettigrew J. Andrew Bradley 《Clinical transplantation》2014,28(3):345-353
It is essential to minimize the unnecessary discard of procured deceased donor kidneys, but information on discard rates and the extent to which discard can be avoided are limited. Analysis of the UK Transplant Registry revealed that the discard rate of procured deceased donor kidneys has increased from 5% in 2002‐3 to 12% in 2011‐12. A national offering system for hard‐to‐place kidneys was introduced in the UK in 2006 (the Declined Kidney Scheme), but just 13% of kidneys that were subsequently discarded until 2012 were offered through the scheme. In order to examine the appropriateness of discard, 20 consecutive discarded kidneys from 13 deceased donors were assessed to determine if surgeons agreed with the decision that they were not implantable. Donors had a median (range) age of 67 (31–80) yr. Kidneys had been offered to a median of 3 (1–12) centers before discard. Four (20%) of the discarded kidneys were thought to be usable, and nine (45%) were possibly usable. As a result of these findings, major changes to the UK deceased donor kidney offering system have been implemented, including simultaneous offering and broader entry criteria for hard‐to‐place kidneys. Organizational changes are necessary to improve utilization of deceased donor kidneys. 相似文献
76.
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78.
Immediate and short-term benefit of multilesion coronary angioplasty: influence of degree of revascularization 总被引:8,自引:0,他引:8
M G Vandormael B R Chaitman T Ischinger U T Aker M Harper J Hernandez U Deligonul H L Kennedy 《Journal of the American College of Cardiology》1985,6(5):983-991
The safety and short-term therapeutic benefit of multilesion percutaneous transluminal coronary angioplasty was assessed in 135 patients, 66 of whom had a minimum of 6 months of follow-up study. Primary success, defined as successful dilation of the most critical lesion or all lesions attempted without major in-hospital complications was obtained in 117 (87%) of the 135 patients. Cardiac complications associated with the procedure were uncommon; prolonged angina occurred in 5% and myocardial infarction in 3%; emergency coronary bypass surgery was performed in 4% of the patients. There were no deaths. Complete revascularization was achieved in 46% of the 117 patients with a primary success. Of the 66 patients eligible for 6 month follow-up, 80% had an uncomplicated course and required no further procedures. Clinical improvement by at least one angina functional class was observed in 90% of the patients. Cardiac events such as the need for a second revascularization procedure were significantly more common in patients who had incomplete versus complete revascularization (35 versus 9%; p = 0.018). Repeat coronary angiography performed an average of 5 months after angioplasty revealed restenosis in 18 of 22 symptomatic patients and 3 of 9 asymptomatic patients. Restenosis occurred at the site of a single dilation in 12 patients, at two sites in 8 patients and at three sites in 1 patient. Thus, multilesion coronary angioplasty is an important therapeutic option for selected patients with multivessel disease and can be performed with relatively low risk. Improvement in angina status can be expected even in patients who have incomplete revascularization.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
79.
Identification and functional characterization of leukotriene B4 20-hydroxylase of human polymorphonuclear leukocytes. 总被引:4,自引:0,他引:4
R J Soberman T W Harper R C Murphy K F Austen 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(8):2292-2295
A single reaction product was formed during the incubation of 1.5 microM (5S,12R)-dihydroxy-6,14-cis-8,10-trans-[3H]icosatetraenoic acid (leukotriene B4, LTB4) for 30 min at 37 degrees C in 10 mM potassium phosphate buffer (pH 7.5) with 100 microM NADPH and the 150,000 X g supernatant of sonicated human polymorphonuclear leukocytes (PMN). The reaction product exhibited the same mobility on reversed-phase HPLC (RP-HPLC) and TLC as standard 20-hydroxy-LTB4 (20-OH-LTB4). When the omega-oxidation product of [3H]LTB4 was eluted from a Sep-Pak, resolved by RP-HPLC, and analyzed by GC/MS, its structure was determined to be solely 20-OH-LTB4. The Km of the 20-hydroxylase for [3H]LTB4 at its optimal pH of 7.5 was 0.22 +/- 0.08 microM (mean +/- SD, n = 4) and the Vmax was 48 +/- 11 pmol/min X mg of protein (mean +/- SD, n = 4). When the concentration of [3H]LTB4 was fixed at 1.5 microM, the Km for NADPH was 1.01 +/- 0.59 microM (mean +/- SD, n = 3). The location in the 150,000 X g supernatant of the LTB4 20-hydroxylase distinguishes it from the cytochrome P-450 system of liver, lung, and kidney microsomes and from the NADPH oxidase-cytochrome b-245 system of the human PMN. The LTB4 20-hydroxylase is either a unique cytochrome P-450 or other monooxygenase. 相似文献
80.
Placebo‐controlled pilot trial testing dose titration and intravenous,intramuscular and subcutaneous routes for ketamine in depression 下载免费PDF全文