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21.
Gregor Warnecke Murat Avsar Thomas Steinkamp Renate Reinhard Jost Niedermeyer André R Simon Axel Haverich Martin Strüber 《European journal of cardio-thoracic surgery》2005,28(3):454-460
OBJECTIVE: Tacrolimus has been shown to provide superior immunosuppression in various solid organ transplant settings. The purpose of our study was to compare the survival of porcine lung allografts after induction with either cyclosporine A (CsA) or tacrolimus. METHODS: Single lung transplantation from MHC mismatched donors was performed in 10 minipigs. Immunosuppression included 1.5 mg/kg per day methylprednisolone and 1.0 mg/kg per day azathioprine. CsA (n=5) was adjusted to trough levels of 300-500 ng/ml, tacrolimus (n=5) was adjusted to 16-26 ng/ml. All immunosuppressive drugs were discontinued on postoperative day (POD) 28. Allograft survival was monitored by sequential chest radiographs, bronchoscopy and transbronchial biopsy histology. Peripheral blood leukocytes were scanned for donor chimerism and CD3, CD4, CD8 and CD25 expression. RESULTS: The animals survived a 4-week course of immunosuppression without radiological or histological signs of rejection on POD 28. Median allograft survival in CsA-treated animals was 55+/-15 days and all animals rejected their grafts within 42 days after withdrawal of immunosuppression. In tacrolimus-treated animals, median survival was 152+/-65 days with the longest survivor being electively sacrificed on POD 390 (P=0.0064). The degree of donor leukocyte chimerism and the frequency of CD4+CD25+ T-cells were higher in the tacrolimus group, however, these differences were not statistically significant. CONCLUSION: The results of our study show that primary immunosuppression with tacrolimus is superior to cyclosporine after pulmonary allotransplantation in a large animal model. 相似文献
22.
Evaluation of 188 consecutive homografts implanted in pulmonary position after 20 years. 总被引:1,自引:0,他引:1
Dietmar Boethig Heidi Goerler Mechthild Westhoff-Bleck Masamichi Ono Anna Daiber Axel Haverich Thomas Breymann 《European journal of cardio-thoracic surgery》2007,32(1):133-142
OBJECTIVE: Homografts are considered the gold standard for right ventricular outflow tract reconstruction. Their long-term durability is limited, and alternatives became available. We evaluate their long-term hemodynamic performance to permit comparisons with alternative devices. METHODS: Between 1985 and 2004, 188 homografts were implanted in pulmonary position at our institution. Mean patient age was 24.8 years (range 2 days-75 years); 56 were female and 132 male. Total follow-up time was 1073 years. Fifty-eight percent were Ross procedures (mean age 31.5 years) and 42% were different procedures (mean age 15.6 years); main diagnoses were tetralogy of Fallot (48%), truncus arteriosus (14%), transposition of the great arteries (11%). Twenty-six percent were redo implantations. We evaluated freedom from death, explantation, insufficiency, relevant gradient, degeneration, and the interval between diagnosis of degeneration and therapeutic procedure (therapeutic gap). Results were stratified by indication, age, history, homograft size, and origin. RESULTS: Ten-year-freedom-from explantation was 82% in homografts >19 mm and 45% in smaller ones. Ten-year freedom from degeneration was 68% after Ross procedure and 25% after other operations; it was 83% in patients older than 10 years at implantation and 51% in younger ones. 'Non-Ross-procedure' and 'implantation age below 10 years' were the only independent risk factors for degeneration. The observed trend towards therapeutical gap reduction was not statistically significant. CONCLUSIONS: Homograft implantation in the pulmonary position can be performed with good long-term freedom from explantation. However, freedom from degeneration is a matter of concern. Therefore, alternative valved conduits are required especially for pediatric patients. 相似文献
23.
Carpal tunnel syndrome and gynaecomastia during growth hormone treatment of elderly men with low circulating IGF-I concentrations 总被引:1,自引:0,他引:1
Lester Cohn Axel G. Feller Michael W. Draper Inge W. Rudman Daniel Rudman 《Clinical endocrinology》1993,39(4):417-425
OBJECTIVE We studied the relationship between plasma level of insulin-like growth hormone I (IGF-I), changes in lean body mass and in adipose mass, and adverse side-effects during human growth hormone (hGH) treatment of elderly men who had low IGF-I levels. DESIGN The first six months was a period of baseline observation. The subjects were then randomized into two groups so that during months 7–18, men in group I received hGH, and men in group II served as untreated controls. SUBJECTS Eighty-three overtly healthy elderly men, who were selected because their plasma IGF-I level was less than 0.35 units/ml. The men were randomly assigned in a ratio of three to one into group I (n= 62) or into group II (n= 21). MEASUREMENTS Plasma IGF-I level was measured monthly. Lean body mass and adipose mass were measured every six months. RESULTS Fifteen men left the study during the baseline period because of personal reasons or intercurrent medical events. In those who received drug (group I), there were a number of adverse reactions which could have been related to the hGH therapy: carpal tunnel syndrome 10, gynaecomastia 4, and hyperglycaemia 3. In total there were 27 dropouts from group I and two dropouts from group II after the six-month point, for a variety of medical and non-medical reasons, the majority probably not related to hGH therapy. During the hGH treatment of group I, plasma IGF-I increased from the range 0.10–0.35 units/ml into the range 0.5–2.2 units/ml. Among the 18 men who completed 12 months of hGH treatment without experiencing one of the three above-noted presumed hGH side-effects, mean and peak plasma IGF-I during treatment were significantly lower than among the 13 men who experienced carpal tunnel syndrome or gynaecomastia (one subject had both) while on hGH. With one exception, neither carpal tunnel syndrome nor gynaecomastia occurred in any individual with a mean IGF-I level less than 10 units/ml during hGH treatment. Twelve months of hGH treatment (group I) caused an increase in lean body mass to 106% of the initial baseline (month one of the protocol), and a reduction in adipose mass to 84% of the baseline. Meanwhile, the lean body mass of the untreated men in group II declined to 97% of the initial baseline. The body composition responses after 12 months of treatment in group I were larger in the men whose mean intra-treatment IGF-I level was 0.5–1.0 units/ ml, than in the men whose mean intra-treatment IGF-I level was 1.0–1.5 units/ml. CONCLUSIONS These observations show that when elderly men with low circulating IGF-I concentrations are treated continuously with hGH, elevation of plasma IGF-I above 10 units/ml is associated with a substantial frequency of carpal tunnel syndrome or gynaecomastia. It may be that the effects of the hormone in expanding lean body mass and reducing adipose mass can be achieved, and the side-effects avoided, by maintaining the mean IGF-I level in the range 0.5–1.0 units/ml. 相似文献
24.
Priv.-Doz. Dr. Andreas Dávid Axel Ekkernkamp Gert Muhr 《Operative Orthopadie und Traumatologie》1994,6(3):196-207
Operationsprinzip Korrektur eines Pes equinus adductus durch keilf?rmige Resektion des Chopart-Gelenkes mit Keilbasis dorsolateral. Bei gleichzeitigem
Pes varus keilf?rmige Resektion des subtalaren Gelenkes mit Keilbasis lateral (Lange 1962 [7], Myerson et al. 1986 [8], Witt
et al. 1985 [13]) (Abbildungen 1a bis 1f).
Bei gleichzeitigem Tarsaltunnelsyndrom Dekompression des Nervus tibialis durch Spaltung des Retinaculum musculi flexorum.
Zur Korrektur von Krallenzehen Resektion der jeweiligen distalen Grundphalangen nach Hohmann; bei flektierten Endgelenken
Resektion der distalen Mittelphalangen. (Auf diese Techniken wird hier nicht eingegangen).
相似文献
25.
Dara L. Kraitchman Norbert Wilke Erik Hexeberg Michael Jerosch-Herold Ying Wang Todd B. Parrish Cheng-Ning Chang Yi Zhang Robert J. Bache Leon Axel 《Magnetic resonance in medicine》1996,35(5):771-780
MRI studies of first-pass contrast enhancement with polylysine-Gd-DTPA and myocardial tagging using spatial modulation of magnetization (SPAMM) were performed to assess the feasibility of a combined regional myocardial blood flow and 2D deformation exam. Instrumented closed-chest dogs were imaged at a baseline control state (Cntl) followed by two interventions: moderate coronary stenosis (St) achieved by partial occlusion of the left anterior descending (LAD) and moderate coronary stenosis with dobutamine loading (StD). Hypoperfusion of the anterior region (ANT) of the myocardium (LAD distribution) relative to the posterior wall (POS) based on the upslope of the signal intensity time curve from the contrast-enhanced MR images was demonstrated only with dobutamine loading (ANT:POS Cntl=1.077 ± 0.15 versus ANT:POS StD=0.477 ± 0.11, P<0.03) and was confirmed with radio-labeled microspheres measurements (ANT:POS Cntl=1.18 ± 0.2 ml/min/g versus ANT:POS StD=0.44 ± 0.1 ml/min/g; P<0.002). Significant changes in regional myocardial shortening were only seen in the StD state (P<0.02); the anterior region showed impaired myocardial shortening with dobutamine loading (P=NS), whereas the nonaffected POS region showed a marked increase in shortening when compared with Cntl (Cntl=0.964 ± 0.02 versus StD=0.884 ± 0.03; P<0.001). These results demonstrate that an integrated quantitative assessment of regional myocardial function and semiquantitative assessment of myocardial blood flow can be performed noninvasively with ultrafast MRI. 相似文献
26.
Biskup C Kelbauskas L Zimmer T Benndorf K Bergmann A Becker W Ruppersberg JP Stockklausner C Klöcker N 《Journal of biomedical optics》2004,9(4):753-759
Resonance energy transfer (RET) has been extensively used to estimate the distance between two different fluorophores. This study demonstrates how protein-protein interactions can be visualized and quantified in living cells by time-correlated single-photon counting (TCSPC) imaging techniques that exploit the RET between appropriate fluorescent labels. We used this method to investigate the association of the potassium inward rectifier channel Kir2.1 and the neuronal PDZ protein PSD-95, which has been implicated in subcellular targeting and clustering of ion channels. Our data show that the two proteins not only colocalize within clusters but also interact with each other. Moreover, the data allow a spatially resolved quantification of this protein-protein interaction with respect to the relative number and the proximity between interacting molecules. Depending on the subcellular localization, a fraction of 20 to 60% of PSD-95 molecules interacted with Kir2.1 channels, approximating their fluorescent labels by less than 5 nm. 相似文献
27.
Analysis of microdissected prostate tissue with ProteinChip arrays--a way to new insights into carcinogenesis and to diagnostic tools 总被引:9,自引:0,他引:9
Wellmann A Wollscheid V Lu H Ma ZL Albers P Schütze K Rohde V Behrens P Dreschers S Ko Y Wernert N 《International journal of molecular medicine》2002,9(4):341-347
Prostate carcinomas are one of the most common malignancies in western societies. The pathogenesis of this tumor is still poorly understood. These tumors present with two characteristic features: epithelial-mesenchymal interactions, which play a pivotal role for tumor development and most of clinically manifest cancers arise in prostate proper compared to a minority of tumors which develop in the transitional zone. Deciphering the epithelial-mesenchymal cross talk and identification of molecular pecularities of the sub-populations of cells in different zones can therefore help understanding carcinogenesis and development of new, non-invasive tools for the diagnosis and prognosis of prostate carcinomas which has remained a challenge until today. A ProteinChip array technology (SELDI = surface enhanced laser desorption ionization) has been developed recently by Ciphergen Biosystems enabling analysis and profiling of complex protein mixtures from a few cells. This study describes the analysis of approximately 500-1000 freshly obtained prostate cells by SELDI-TOF-MS (surface enhanced laser desorption ionization time-of-flight mass spectrometry). Pure cell populations of stroma, epithelium and tumor cells were selected by laser assisted microdissection. Multiple specific protein patterns were reproducibly detected in the range from 1.5 to 30 kDa in 28 sub-populations of 4 tumorous prostates and 1 control. A specific 4.3 kDa peak was increased in the prostate tumor stroma compared to normal prostate proper and transitional zone stroma and increased in prostate tumor glands compared to normal prostate proper and transitional zone glands. Coupling laser assisted microdissection with SELDI provides tremendous opportunities to identify cell and tumor specific proteins to understand molecular events underlying prostate carcinoma development. It underlines the vast potential of this technology to better understand pathogenesis and identify potential candidates for new specific biomarkers in general which could help to screen for and distinguish disease entities, i.e. between clinically significant and insignificant carcinomas of the prostate. 相似文献
28.
29.
Mulders AG Laven JS Eijkemans MJ de Jong FH Themmen AP Fauser BC 《Human reproduction (Oxford, England)》2004,19(9):2036-2042
BACKGROUND: Anti-Müllerian hormone (AMH), produced by growing pre-antral and early antral ovarian follicles, has been shown to be a useful marker for ovarian ageing. Serum AMH concentrations are elevated during reproductive life in anovulatory women, especially in those patients exhibiting polycystic ovaries (PCO). The current study was designed to investigate whether the decrease in AMH serum concentrations over time is different comparing women with normogonadotrophic anovulation [World Health Organization (WHO) group 2 (including polycystic ovary syndrome (PCOS)] and normo-ovulatory controls. METHODS AND RESULTS: AMH serum levels were assessed on two occasions in 98 patients suffering from WHO 2 anovulatory infertility as well as in 41 normo-ovulatory premenopausal women. Median time interval between both visits was 2.6 years (range 0.3-9.0) for WHO 2 patients compared with 1.6 years (range 1.0-7.3) in controls. Serum AMH concentrations were significantly (P < 0.0001) elevated on both occasions in WHO 2 patients (AMH1, median = 7.5 microg/l, range 0.1-35.8; and AMH2, median = 6.7 microg/l, range 0.0-30.6) compared with controls (AMH1, median = 2.1 microg/l, range 0.1-7.4; and AMH2, median = 1.3 microg/l, range 0.0-5.0). Regression analysis, corrected for age, indicated a significant relative decrease in serum AMH concentrations over time for both groups (P < 0.001). However, the decline in serum AMH in WHO 2 patients was significantly less compared with controls (P = 0.03). CONCLUSION: The present longitudinal study shows that serum AMH concentrations decrease over time both in women presenting with WHO 2 anovulatory infertility and in normo-ovulatory controls. The decrease in WHO 2 patients is less pronounced despite distinctly elevated concentrations. This observation may suggest retarded ovarian ageing and hence a sustained reproductive life span in these patients. 相似文献
30.
Paulo R. Dellani Martin Glaser Paulo R. Wille Goran Vucurevic Axel Stadie Thomas Bauermann Andrei Tropine Axel Perneczky Aldo von Wangenheim Peter Stoeter 《Journal of digital imaging》2007,20(1):88-97
Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiological institutions. Images combining anatomical information and the localization of different fiber tract trajectories can be encoded and exported in DICOM and Analyze formats, which are valuable resources in the clinical applications of this method. Fiber tracking was implemented based on existing line propagation algorithms, but it includes a heuristic for fiber crossings in the case of disk-shaped diffusion tensors. We successfully performed fiber tracking on MR-DTI data sets from 26 patients with different types of brain lesions affecting the corticospinal tracts. In all cases, the trajectories of the central spinal tract (pyramidal tract) were reconstructed and could be applied at the planning phase of the surgery as well as in intraoperative neuronavigation. 相似文献