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51.
BACKGROUND: Cytomegalovirus (CMV) infection in recipients of cardiac transplants is associated with higher rates of morbidity. A recent phase III trial showed highly significantly (P<0.001) lower CMV rates with the proliferation signal inhibitor everolimus compared to azathioprine (AZA). To better define this association, data on CMV risk factors were collected retrospectively and analyzed. METHODS: Data on CMV risk factors from a multicenter phase III trial on de novo heart transplant recipients (n=634) receiving a triple immunosuppressive regimen randomized to everolimus 1.5 mg/day (group 1), everolimus 3 mg/day (group 2), or AZA (group 3) were merged with prospectively collected CMV-related outcome data and analyzed. RESULTS: CMV-positive donors (D+) and CMV-negative recipients (R-) were evenly distributed across groups 1-3 at 36/209 (17.2%), 48/211 (22.7%), and 38/214 (17.8%), respectively. CMV prophylaxis had been given for a mean (SD) of 175 (127.8), 183 (137.1), and 177 (132.9) days, respectively. In the high-risk D+/R- subgroup with prophylaxis, the proportions of patients with CMV infection compared with group 3 (12/29 [41.4%]) were 3/25 (12.0%) in group 1 (P=0.031) and 6/36 (16.7%) in group 2 (P=0.049). In D+/R+ subgroups either with or without prophylaxis, the everolimus groups had less CMV disease (P<0.001). The incidence of CMV syndrome, organ involvement, and laboratory evidence was lower with everolimus use compared to AZA. CONCLUSIONS: Everolimus is associated with lower rates of CMV infection, syndrome, or organ involvement, suggesting an additional advantage from the use of everolimus in cardiac transplant recipients.  相似文献   
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Intracranial vascular stenosis of haemodynamic significance is underappreciated both clinically and diagnostically. It is thought to be the cause of cerebral ischaemia in 8% of patients. Now it is possible to perform dilatation of the intracranial arterial stenosis by modern intraarterial angioplasty. Two cases are presented of successful dilatation of middle cerebral artery trunk stenosis. Diagnostic problems, follow up and pharmacological treatment as well as technique of intravascular treatment is described.  相似文献   
55.
BackgroundMixed adenoneuroendocrine carcinoma (MANEC) is currently included in the category of neuroendocrine carcinomas but the therapeutically management is not yet defined.AimsTo present the immunohistochemical (IHC) features of the epithelial mesenchymal transition (EMT) of MANEC.Materials and methodsThe clinicopathological features of 13 consecutive cases of MANEC (6 gastric and 7 colorectal) were correlated with the IHC expression of the biomarkers E-cadherin, β-catenin, N-cadherin, vimentin, maspin, CD44 and S100. In all of the cases open surgery was performed.ResultsAll of the cases showed microsatellite stable status, expressed E-cadherin and membrane β-catenin in both components (neuroendocrine and adenocarcinoma) and were negative for N-cadherin, vimentin and S-100. The colorectal MANECs were negative for maspin. In gastric MANECs, maspin showed cytoplasm positivity in the neuroendocrine component and nuclear translocation in the adenocarcinoma cells. CD44 was positive in all of the cases, in both components. No tumor buddings were identified. Three of the 13 patients survived for at least 32 months, all of them showing lymphatic emboli but not lymph node metastases. Pure neuroendocrine lymph node metastases were seen in only four of the cases: one from stomach, two of the ascending colon and two cases of the upper rectum.ConclusionsGastrointestinal MANEC is a microsatellite stable tumor with nodular growth, which components might originate from a CD44-positive stem-like precursor cell. Lymph node status remains the most reliable prognostic parameter and agressivity seems to not be influenced by tumor budding degree or EMT-related features. The histologic aspect of metastatic component (neuroendocrine versus adenocarcinoma) should be included in the histopathological reports and might be used for establishing the proper-targeted therapy of MANEC.  相似文献   
56.

Introduction  

Patients in the intensive care unit (ICU) may be in an inadequate condition to give their informed consent for research. The aim of this study was to analyse the ability to recall participation in a clinical trial for which ICU patients had given their consent.  相似文献   
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The safety and efficacy of ivabradine applied in heart transplant (HTx) recipients with permanent sinus tachycardia (PST) has been depicted in previous short-term follow-up studies. We sought to investigate the long-term impact of ivabradine in this patient population. From May to November 2006, 29 HTx recipients with PST, who exhibited either contraindications or intolerance of beta-blocker medication or insufficient heart rate (HR) reduction on beta-blocker treatment, first received oral ivabradine treatment (5 mg bid). Ivabradine treatment was discontinued in three patients due to adverse events within the first week. In the remaining 26 patients, resting HR was significantly lowered from 106.8 ± 9.2 at baseline to 83.2 ± 5.1 bpm after 3 months (p < 0.001). This effect remained stable in the long-term follow-up (82.1 ± 11.8 bpm after 4 years), whilst blood pressure was not affected. Apart from the corrected QT interval (QTc), there were no significant changes in ECG. The elongated QTc at baseline (469.4 ± 29.5 ms) decreased to 444.3 ± 33.1 ms after 3 months ivabradine treatment (p < 0.001). A decrease in QTc until month 9 was observed, followed by a partial increase to the upper limit of the normal value. Neither allograft rejection nor changes in left ventricular ejection fraction were observed over the follow-up period. In conclusion, ivabradine appears to be a safe and feasible long-term therapeutic option for HTx recipients with PST. It reduced the resting HR without impairment of blood pressure, myocardial contractility and cardiac conduction. The prognostic value of normalised QTc following ivabradine administration requires further observation.  相似文献   
58.
Chronic hepatitis B progresses to cirrhosis in the majority of immunosuppressed patients. The outcome of long-term antiviral therapy in HBV-infected organ transplant recipients is unknown. In 1996, we included 20 heart transplant (HT) recipients in a pilot trial to treat chronic hepatitis B with famciclovir. At that time, bridging fibrosis or cirrhosis was evident in 15 individuals (75%). From 1998 onwards, patients were switched to lamivudine in case of primary or secondary virological nonresponse to famciclovir. Adefovir or tenofovir became available at our centre for HT recipients in 2002. After 103 months, one patient was still on famciclovir showing a complete virological response. Sixteen patients were switched to lamivudine after 0.5-4 years of famciclovir therapy. Six of those showed a long-term response to lamivudine therapy lasting for up to 7 years. Lamivudine resistance developed in the remaining 10 patients (63%), in 4 of them successful rescue therapy (adefovir n = 3, tenofovir n = 1) could be initiated. Only one hepatocellular carcinoma developed, which was successfully treated by locoregional ablative therapy. Nine patients died (45%), with lamivudine-resistance-related liver failure as the cause of death in five cases. Significant improvement of Ishak fibrosis scores could be demonstrated in six of the seven patients with more than two sequential liver biopsies available. Long-term antiviral therapy of chronic hepatitis B can lead to regression of liver cirrhosis in patients after organ transplantation, unless viral resistance occurs. This study demonstrates the urgent need for further antivirals to overcome antiviral resistance.  相似文献   
59.
Multiferroic solid solutions of Ba1−xLaxTi1−x/4O3 and iron (BLFT) were synthesized using the conventional mixed oxide method. The dependence of the piezoelectric coefficients on Fe content in BLFT ceramics was determined by the quasi-static and resonance method. The results indicate that 0.3 mol% addition of Fe3+ ions to the ceramic structure increased the value of the piezoelectric parameter d33 to the maximum of 159 pC/N. This puts BLFT ceramics among other good-quality and lead-free piezoelectric ceramics. A major enhancement of dielectric properties related to the manipulation of Fe content in the barium lanthanum titanate (BLT) ceramics system is reported as well.  相似文献   
60.
INTRODUCTION: Coronary angiography is regarded as the gold standard in evaluating graft patency, Multi-slice CT (MSCT) which enable rapid imaging of cardiac structures, including coronary arteries may be a less invasive technique. Therefore in our institution a prospective pilot study was performed combining these procedures. PATIENTS AND METHODS: Starting from July 2004 a study was done with 13 patients. They received TAR using composite left internal thoracic artery (LITA) and left radial artery (RA) as T-graft. Intra-operative angiography was performed in these patients to confirm graft patency. Follow-up control (9-21 months) was performed with exercise Ergometry and 64 slides MSCT. RESULT: Mean procedure time for intra-operative angiography was 13.7 +/- 7.3 min and mean fluoroscopy time was 6.2 +/- 4.6 min. In one patient, RA-marginal artery side to side anastomoses was stenosed and had to be revised. And in another, there was a kinking of the LITA and was corrected. At follow-up, exercise ergometry showed no signs of angina or ECG-changes in all patients. MSCT showed occluded radial artery grafts in two patients. In two other patients interpretation was difficult due to resolution reasons. In all patients the LITA graft was patent. CONCLUSION: The intra-operative graft angiography can be performed in patients undergoing TAR easily. MSCT can be used for post-operative less-invasive angiography with limitations in patients with small graft/coronary diameters and arrhythmias. However, this study shows that an interdisciplinary cooperation is a new possibility toward quality control during and after TAR.  相似文献   
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