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21.
BACKGROUND AND AIM OF THE STUDY: Aortic valve replacement using homografts is an accepted alternative to the use of other replacement devices, and has been established at the authors' institution for more than 10 years. METHODS: Since 1992, a total of 389 homografts was implanted, and 332 patients (mean age 54 years, 72% males) were followed up. The initial patients (n = 75) had subcoronary implantation, all subsequent patients had root replacement. Both aortic grafts (AG) and pulmonary grafts (PG) were used. Follow up was conducted with regard to the factors 'graft origin', 'implantation technique' and 'gender', and included clinical examination, ECG and transthoracic echocardiography on an annual basis. RESULTS: Overall 30-day mortality was 5.4% (AG patients 3.9%, PG patients 13.5%; p = 0.09). Among late deaths (n = 22), six were valve-related (all prosthetic infection). Four minor thrombembolic events were recorded due to amaurosis fugax and transient ischemic attacks (TIA). Freedom from reoperation was 86.5%. Indication for graft replacement was greater after subcoronary implantation than after root implantation (p = 0.04). Reoperation was necessary in 24 patients due to restenosis (n = 4), regurgitation grade >II (n = 5), paravalvular leak (n = 2) and prosthetic infection (n = 13). At the latest echocardiographic follow up, mean peak pressure gradient was 15.60 +/- 11.76 mmHg, homograft regurgitation grade was 0.82 +/- 0.66, left ventricular end-diastolic diameter (EDD) was 49.1 +/- 7.54 mm, and mean aortic root diameter was 30.54 +/- 5.48 mm. When comparing parameters at a mean of five years postoperatively, the pressure gradient increased from 10.26 to 15.02 mmHg, regurgitation grade increased from 0.53 to 0.81, and EDD decreased from 52.3 to 50.4 mm. Other variables showed no significant differences. CONCLUSION: The present results confirmed good midterm-results for aortic valve replacement with homografts. These prostheses are vulnerable to infection, and root replacement was superior to the subcoronary implantation technique.  相似文献   
22.
OBJECTIVES: The purpose of this study was to assess the follow-up of patients with vaccinia-associated myocarditis. BACKGROUND: With the threat of biological warfare, the U.S. Department of Defense resumed a program for widespread smallpox vaccinations on December 13, 2002. One-year afterwards, there has been a significant increase in the occurrence of myocarditis and pericarditis among those vaccinated. METHODS: Cases were identified through sentinel reporting to military headquarters, systematic surveillance, and spontaneous reports. RESULTS: A total of 540,824 military personnel were vaccinated with a New York City Board of Health strain of vaccinia from December 2002 through December 2003. Of these, 67 developed myopericarditis at 10.4 +/- 3.6 days after vaccination. The ST-segment elevation was noted in 57%, mean troponin on admission was 11.3+/- 22.7 ng/dl, and peak cardiac enzymes were noted within 8 h of presentation. On follow-up of 64 patients (96%) at a mean of 32 +/- 16 weeks, all patients had objective normalization of echocardiography, electrocardiography, laboratory testing, graded exercise testing, and functional status; 8 (13%) reported atypical, non-limiting persistent chest discomfort. CONCLUSIONS: Post-vaccinial myopericarditis should be considered in patients with chest pain within 30 days after smallpox vaccination. Normalization of echocardiography, electrocardiography, and treadmill testing is expected, and nearly all patients have resolution of chest pain on follow-up.  相似文献   
23.
OBJECTIVES: We investigated the acute and long-term hemodynamic and neurohumoral effects of the vasopeptidase inhibitor omapatrilat in human heart failure. BACKGROUND: Angiotensin-converting enzyme (ACE) inhibition constitutes a major advance in the treatment of chronic heart failure (CHF). Simultaneous inhibition of both neutral endopeptidase and ACE with omapatrilat may represent a new treatment strategy in CHF. METHODS: Three hundred and sixty-nine patients with symptomatic heart failure were randomized to double-blind treatment with omapatrilat (first 190 patients: 2.5 mg, 5 mg or 10 mg; last 179 patients: 2.5 mg, 20 mg or 40 mg once daily) for 12 weeks. RESULTS: Acutely, the 10 mg, 20 mg and 40 mg doses of omapatrilat produced greater reductions in pulmonary capillary wedge pressure (PCWP), systolic blood pressure (SBP) and systemic vascular resistance compared with 2.5 mg. Higher doses were associated with greater increases in vasodilator and natriuretic peptides, in addition to ACE inhibition. After 12 weeks, omapatrilat 20 mg and 40 mg showed greater falls from baseline in PCWP (40 mg: 0 h to 12 h average change -7.3 +/- 0.8 mm Hg) and SBP (40 mg: -11.7 +/- 1.7 mm Hg) than 2.5 mg (both p < 0.01 vs. 2.5 mg). The incidence of adverse experiences and patient withdrawal were similar in all groups. CONCLUSIONS: In CHF, the acute hemodynamic benefit seen with higher doses of omapatrilat was associated with increases in plasma vasodilator and natriuretic peptide levels in addition to ACE inhibition. After 12 weeks, the hemodynamic benefit was maintained. Omapatrilat may be a promising new agent in CHF.  相似文献   
24.
MircoRNAs as a new class of regulatory molecules have been investigated in many specific cells and organs in healthy and diseased conditions. Although miRNA signatures can be directly assessed in patients' affected tissues such as tumor sections, recent studies revealed that miRNA profiles can also be obtained indirectly, that is, from the patients' peripheral blood. For better understanding of miRNA's contribution to gastric carcinoma (one of the leading causes of cancer‐related mortality worldwide), we screened for deregulated miRNAs in blood collected from human cancer patients and compared the expression patterns with a gastric carcinoma mouse model (Tff1 knock‐out). The profiles were assessed using species‐specific miRNA microarrays. Among many dozens of deregulated miRNAs (219 in H. sapiens; 75 in M. musculus), a subset of eight miRNAs comparable in sequence from both species was noted. By in silico analysis, their involvement in targeting neoplastic and MAPkinase pathways was demonstrated. We found a high probability of linkage of all noted miRNAs to pathways in cancer with P‐values of 0.013 and 0.018 in mice and humans, respectively. Linkage to the MAPK‐signaling pathway in mice was observed with a P‐value of 0.01. Moreover, when comparing the 219 deregulated miRNAs obtained from blood with deregulated miRNAs derived from gastric cancer (GC) tissues, as published previously, 24 miRNAs were identical. If confirmed in a larger patient pool, these miRNAs could constitute appropriate blood‐born biomarkers for GC. © 2012 Wiley Periodicals, Inc.  相似文献   
25.
Strahlentherapie und Onkologie - The purpose of the present study was to evaluate the clinical outcome of CT-guided high-dose-rate brachytherapy (CT-HDRBT) in patients with unresectable...  相似文献   
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BACKGROUND: The rate constant for global fatty acid influx (k(1)) was studied in 12 male patients with dilated cardiomyopathy (DCM). METHOD: 10 normal subjects served as controls. 201-Thallium (201TI) and [123I]-phenyl-pentadecanoic acid (IPPA) were administered during bicycle exercise under fasting conditions. RESULTS: All patients showed non-homogeneous tracer uptake defects for 201TI and IPPA. k(1) was significantly higher in DCM patients than controls. k(1) showed significant inverse correlation between cardiac index, left-ventricular ejection fraction, left-ventricular enddiastolic pressure and echocardiographic left-ventricular ejection fraction. CONCLUSION: We presume that an increased regional rate constant of IPPA influx into the myocardial tissue in patients with DCM reflects a compensatory mechanism of altered myocardium.  相似文献   
29.
Loosening of orthodontic and orthopedic implants is a critical and common clinical problem. To minimize the numbers of revision surgeries due to peri-implant inflammation or insufficient osseointegration, developments of new implant manufacturing strategies are indicated. Ultrafast laser surface texturing is a promising contact-free technology to modify the physicochemical properties of surfaces toward an anti-infectious functionalization. This work aims to texture Ti6Al4V surfaces with ultraviolet (UV) and green (GR) radiation for the manufacturing of laser-induced periodic surface structures (LIPSS). The assessment of these surface modifications addresses key aspects of topography, morphology and chemical composition. Human primary mesenchymal stromal cells (hMSCs) were cultured on laser-textured and polished Ti6Al4V to characterize the surfaces in terms of their in vitro biocompatibility, cytotoxicity, and metal release. The outcomes of the in vitro experiment show the successful culture of hMSCs on textured Ti6Al4V surfaces developed within this work. Cells cultured on LIPSS surfaces were not compromised in terms of their viability if compared to polished surfaces. Yet, the hMSC culture on UV-LIPSS show significantly lower lactate dehydrogenase and titanium release into the supernatant compared to polished. Thus, the presented surface modification can be a promising approach for future applications in orthodontics and orthopedics.  相似文献   
30.

Background

Elevated IgG4 levels have been reported among patients with primary sclerosing cholangitis. Epidemiological data has only been provided from tertiary centres.

Aims

To investigate the prevalence of elevated IgG4 levels and to compare prognosis between patients with and without elevated IgG4 levels in serum in two European cohorts of patients with primary sclerosing cholangitis.

Methods

Serum IgG4-levels were measured in a consecutive series of patients from Berlin, and retrospectively collected in a population-based cohort from Sweden (total N = 345). Cox's proportional hazard analysis was used to calculate relative risks for liver-related death or liver transplantation and cholangiocarcinoma.

Results

Elevated IgG4 values were demonstrated in 10% of patients. A previous history of pancreatitis, combined intra- and extrahepatic biliary involvement and jaundice were independently associated with elevated IgG4 in multivariate analysis. IgG4 status was not associated with an increased risk for the combined endpoint liver-related death or liver transplantation or cholangiocarcinoma.

Conclusion

The prevalence of elevated IgG4 values among European patients with primary sclerosing cholangitis is similar to what previously has been reported from the United States. Elevated IgG4 was not associated with an increased risk of liver transplantation or liver-related death or cholangiocarcinoma.  相似文献   
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