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Dr. Peter Lanzer Dr. Ralf Weser Dr. Christiane Prettin 《Clinical research in cardiology》2006,95(11):584-590
AIMS: The aim of this study was to document the early outcome of coronary-like revascularization for atherosclerotic renal artery stenosis (ARAS). METHODS AND RESULTS: A total of 181 consecutive patient, 102 men, mean age 66.1 (+/- 9.2) years and 79 females, mean age 68.4 (+/- 9.2) years and 198 lesions were treated between February 1999 and May 2004 for ARAS and retrospectively analyzed. At least one major cardiovascular risk factor was present in 179 (98.9%) patients. Pre-dilatation ARAS was 81.3+/-9.6%, 27 ARAS were 50-70% and no ARAS was <50%. 135 (68.2%) of the ARAS lesions were ostial and 63 (31.8%) were non-ostial. In 17 (9.4%) patients bilateral ARAS were present. Technical success defined as residual stenosis < or =30% was achieved in 178 (98.3%) of patients and 195 (98.5%) of lesions. In one patient (0.5%) the target ARAS could not be crossed, in two (1.1%) patients residual stenosis was >30%. No major adverse cardiac or cerebral effects were observed. In 3.9% of patients minor local complications of the access site occurred; 4 (2.2%) inguinal hematoma, 3 (1.7%) pseudoaneurysm were documented. Serum creatinine concentrations and systolic and diastolic blood pressure before and after the intervention were not statistically different. CONCLUSIONS: Coronary-like approach to ARAS revascularization is technically feasible and associated with a very low complication rate. 相似文献
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Hans-Holger Capelle Johannes C W?hrle Ralf Weigel Hansj?rg B?zner Eva Grips Joachim K Krauss 《Movement disorders》2004,19(10):1202-1208
It is well known that brain injury or central traumatic lesions may result in the subsequent appearance of movement disorders such as dystonia or tremor. The concept that peripheral lesions to neural structures may be involved in the pathogenesis of movement disorders has been discussed controversely but has gained more widespread acceptance only recently. Here, we report on 6 patients who developed movement disorders after spinal disc surgery. The movement disorders became manifest with a delay of 1 day to 12 months after surgery. Of the six patients, 4 underwent cervical disc surgery, and 2 patients were operated on for lumbar disc herniation; 2 patients presented with paroxysmal kinesigenic segmental dystonia, 1 patient with focal dystonia, 2 with unilateral tremor, and 1 with bilateral tremor. The appearance of the movement disorder was associated with persistent dermatomal or segmental pain. In all patients, the anatomic distribution of the movement disorder was related to the nerve root or spinal segment of the corresponding disc level and the manifestation was in close temporal relation to the surgery. We conclude that spinal disc surgery may be another, thus far neglected, cause for movement disorders. The postoperative pain syndrome in all patients should be considered as an important factor of pathogenesis. Overall, movement disorders associated with disc surgery appear to be rare, yet they may cause significant discomfort to the affected individual. 相似文献
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Genetically modified fibroblasts induce angiogenesis in the rat epigastric island flap 总被引:2,自引:0,他引:2
H.-G. Machens Jeffrey R. Morgan Francois Berthiaume Peter Stefanovich Ralf Reimer Alfred C. Berger 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1998,383(5):345-350
Methods: Gene therapy was tested for inducing functional angiogenesis in the superficial rat epigastric island flap to allow earlier
pedicle division. Autologous rat fibroblasts were grown, harvested, cultured and retrovirally transfected to produce platelet-derived
growth factor AA (PDGF-AA), an angiogenetically active protein. Stable gene expression was monitored by PDGF-AA enzyme-linked
immunosorbent assay (ELISA). One hundred and eighty animals were divided into three groups (I–III) and a bilateral flap created
in each animal. In all experiments, the right-sided flap was subjected to experimental treatment and the left-sided flap served
as control (1 ml saline 0.9%). During flap elevation, group I received 5×106 GMFB (genetically modified fibroblasts) plus 1 ml Dul-becco's modified Eagle's medium. Group II was treated with 5×106 NMFB (non-modified fibroblasts) plus 1 ml medium and group III received 1 ml medium only. The flaps were sutured back and
the vascular pedicle was bilaterally ligated and divided in each of ten animals during the following 6 days. After 7 days,
the flaps were harvested, the amount of necrosis measured and histologically examined. Results: The GMFB produced up to 560 times more PDGF-AA than the NMFB, measured by ELISA. The GMFB-treated flaps tolerated surgical
division of the vascular pedicle significantly earlier than groups II and III. Histologically, fibroblasts persisted in all
flaps of groups I and II, without major inflammatory reaction. In all GMFB-treated flaps, massive angiogenesis could be demonstrated.
Conclusion: By means of retroviral gene transfer, autologous rat fibroblasts can be genetically modified for stable expression of the
PDGF-A gene to produce high amounts of PDGF-AA, which is angiogenetically active. After injection into the panniculus carnosus,
these cells induce functional angiogenesis to permit earlier division of the vascular pedicle in this flap model.
Received: 5 January 1998 / Accepted: 17 June 1998 相似文献
18.
Benjamin Sadlack Ralf Kühn Hubert Schorle Klaus Rajewsky Werner Müller Ivan Horak 《European journal of immunology》1994,24(1):281-284
Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice. 相似文献
19.
Ralf Henkel Susan Cooper Khalied Kaskar Wolf-Bernhard Schill Ursula-F. Habenicht Daniel R. Franken 《Journal of assisted reproduction and genetics》1995,12(9):644-649
Purpose
A total of 86 fresh and salt-stored immature human oocytes derived from postmortem ovarian tissue were used for this study.Methods
Oocytes were randomly incubated either in synthetic human tubal fluid medium (untreated zonae) or in a chemically defined medium (treated zonae).Results
Sperm binding experiments using hemizona assay conditions exhibited a 10-fold increased binding of sperm to treated compared to untreated oocytes (272.7±43 versus 24.3±15 sperm bound, respectively; P<0.0001). pH recordings during incubation showed elevated pH levels of 8.1 compared to pH 7.2 among treated and untreated zonae, respectively. Ultrastructural examination showed a spongy appearance of the surface of treated zonae, whereas untreated zonae appeared compact with smooth surface.Conclusions
The marked increase in sperm binding among treated zonae, together with the ultrastructural findings, suggest that the altered zona surface enhances sperm binding. The physiological maturational process of the zona pellucida might be manipulated in vitro, thus increasing sperm binding to the zona.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995. Vienna, Austria. 相似文献
20.
Abstract: Elevated lipoprotein concentrations seem to be linked strongly in a dose dependent manner to an increased incidence of atherosclerosis. A total of 47 patients suffering from severe hyperlipidemia were matched to treatment with LDL apheresis (Baxter, Kaneka, Li–popak; 24 patients, aged 50.2 ±11.5 years), diet, and/or lipid–lowering drugs or with diet and lipid–lowering drugs only (23 patients, aged 48.8 ±11.8 years). After treatment periods of 49.8 ±13.4 months (apheresis group, 2,396 treatment sessions) and 38.6 ± 15.1 months (drug group), the ensuing results revealed significant differences (p <0.0001): –47.3% versus –12.1% for total cholesterol, –46.9% versus –21.8% for LDL, +8.4% versus +0.9% for HDL, –52.0% versus – 13.1% for the LDL/HDL ratio, –36.4% versus –16.2% for triglycerides, and –25.9% versus + 1.5% for lipoprotein (a). In the apheresis group, one patient died of myocardial infarction; in the drug group, there was one nonfatal myocardial infarction and the manifestation of coronary heart disease in 3 cases. There were no severe side effects in either group. All patients in the apheresis group responded to therapy. The present trial suggests that a continuing reduction in serum lipid concentrations may lower, in a dose dependent manner, the risk for development and progression of coronary heart disease. Regarding clinical and laboratory results, LDL apheresis seems to be safe, effective therapy for treatment of severe hyperlipidemia. 相似文献