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11.
An extrachromosomal nucleic acid element was detected in high-molecular-weight DNA preparations formBabesia equi merozoites. This extrachromosomal element was shown to be DNA rather than RNA and had an apparent fragment size of about 9 kilobasepairs (kb). Hybridization experiments using purified 9-kb DNA as a probe revealed sequence homologies with extrachromosomal DNA from two otherBabesia species. 相似文献
12.
13.
Erkki Lotspeich Markus Schoene Heinz Gerngroß Roland Schmidt Reinhard Steinmann Marco Ramadani Susanne Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):559-566
Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer
(UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many
as 20–30% of these patients, however, will develop recurrence.
Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time
polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared
to histopathological findings.
Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal
cancer.
Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR.
Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity)
of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were
positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive
lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA
signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged
on the basis of the molecular findings, no patient would be downstaged.
Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional
lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging. 相似文献
14.
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
15.
Dorota Gabry's Annegret Dörfler Ala Yaromina Franziska Hessel Mechthild Krause Reinhard Oertel Prof. Dr. Michael Baumann 《Strahlentherapie und Onkologie》2008,184(1):48-53
PURPOSE: To evaluate the effect of lovastatin alone or combined with radiation on U87MG and FaDu cells in vitro and U87MG tumors in vivo. MATERIAL AND METHODS: Cell number, p21(WAF1) expression, apoptosis, reproductive cell death, and cell-cycle distribution were investigated after incubation of U87MG and FaDu cells in vitro. The effect of lovastatin (50 mg/kg/day) on tumor growth and on tumor growth delay after single-dose irradiation with 20 Gy was investigated using U87MG tumors in nude mice. RESULTS: Lovastatin dose dependently decreased cell number and proliferation of U87MG and FaDu cells. The proportion of cells in G0/G1 phase, apoptosis and p21 protein expression increased after lovastatin alone or combined with 4-Gy irradiation in both cell lines. Effects of lovastatin on cell cycle and cell number were more pronounced in U87MG compared to FaDu. No radiosensitization of clonogenic cells by lovastatin could be demonstrated in both cells lines, but the colony-forming ability after lovastatin alone was decreased in FaDu cells. In vivo, lovastatin decreased tumor volume over time but did not increase growth delay after irradiation of U87MG tumors with 20 Gy. CONCLUSION: The data support effects of lovastatin on proliferation, apoptosis and colony-forming ability in vitro and tumor volume in vivo. At the drug concentration achievable, lovastatin did not improve the effects of radiation on U87MG tumors in vivo. 相似文献
16.
Norbert Rilinger Johannes Görich Reinhard Scharrer-Pamler Jochen Vogel Reinhard Tomczak Elmar Merkle Roman Sokiranski Hans-Jürgen Brambs 《Cardiovascular and interventional radiology》1997,20(4):263-267
Purpose To evaluate the clinical results of percutaneous transluminal rotational atherectomy in the treatment of peripheral vascular
disease.
Methods Rotational atherectomy was performed in 39 patients aged 39–87 years (mean 66.6 years). A total of 71 lesions (43 stenoses
and 28 occlusions) were treated in 40 limbs. Additional balloon angioplasty was required in 54% of lesions. Fifteen patients
(37.5%) presented in Fontaine stage II, 10 patients (25%) in Fontaine stage III and 15 patients (37.5%) in Fontaine stage
IV. Rotational atherectomy at 750 rpm was carried out over a 0.014-inch guidewire with continuous aspiration into a vacuum,
bottle. Follow-up angiography and color flow Doppler examinations were performed in 22 patients (23 limbs) after a mean period
of 6 months (range 2–14 months)
Results There was one primary technical failure. In 36 of 40 lesions there was a good angiographic result with residual stenoses in
less than 30%. In 70 lesions treated by rotational atherectomy, however, 54% showed residual stenoses of 30%–50% and these
cases required additional balloon angioplasty. The mean ankle-brachial index improved significantly (p<0.001), from 0.49 before the procedure to 1.01 after the procedure. A single distal embolus, related to primary recanalization,
occurred and there were two large inguinal hematomas. Cumulative clinical patency after 6 months was 83.8% and cumulative
angiographic patency after 6 months was 79.1%.
Conclusion Percutaneous rotational atherectomy is a promising approach for the treatment of chronic peripheral vascular disease. Further
prospective, randomized studies are necessary to compare percutaneous transluminal angioplasty with this new technical approach. 相似文献
17.
Margrit Klingner Jenny Apelt Ashok Kumar Dietlind Sorger Osama Sabri J?rg Steinbach Matthias Scheunemann Reinhard Schliebs 《International journal of developmental neuroscience》2003,21(7):357-369
Cholinergic deficits in Alzheimer's disease are accompanied by a number of alterations in other transmitter systems including glutamate, noradrenaline and serotonin, suggesting the involvement also of other neurotransmitter systems in the pathogenesis of the disease. To address the question whether beta-amyloid may contribute to these deficits, brain tissue from transgenic Tg2576 mice with Alzheimer plaque pathology at ages of 5 (still no significant plaque load) and 17 months (moderate to high cortical beta-amyloid plaque load) were examined for a number of cholinergic and non-cholinergic markers. Transgenic mice with no significant plaque load demonstrated reduced hemicholinium-3 (HCh-3) binding to choline uptake sites in anterior brain regions as compared to non-transgenic littermates, while in aged transgenic mice with high number of plaque deposits decreased HCh-3 binding levels were accompanied by increased vesicular acetylcholine transporter binding in selected cortical brain regions. In aged transgenic mice GABA(A), NMDA, AMPA, kainate, and beta-adrenergic as well 5-HT(1A)- and 5-HT(2A)-receptor binding levels were hardly affected, whereas alpha(1)- and alpha(2)-adrenoceptor binding was increased in selected cerebral cortical regions as compared to non-transgenic littermates. The development of changes in both cholinergic and non-cholinergic markers in transgenic Tg2576 mouse brain already before the onset of progressive plaque deposition provides in vivo evidence of a modulatory role of soluble beta-amyloid on cortical neurotransmission and may be referred to the deficits in learning and memory observed in these mice also before significant plaque load. 相似文献
18.
Andon R Kossev Sabine Siggelkow Reinhard Dengler Jens D Rollnik 《Journal of clinical neurophysiology》2003,20(1):54-58
The influence of the intensity of the conditioning stimulus on intracortical inhibition (ICI) and intracortical facilitation (ICF) was assessed in a study using paired-pulse transcranial magnetic stimulation. Interstimulus intervals (ISIs) between conditioning and test stimuli were 3 msec and 13 msec. Latencies and areas of motor evoked potentials in response to the test stimulus were measured in the right extensor carpi radialis muscle. Motor evoked potential areas with ISIs of 3 msec and 13 msec showed a different dependence on the intensity of the conditioning stimulus. In contrast, the changes of motor evoked potential latencies were fairly similar with both ISIs. The findings point to a parallel action of ICI and ICF. Furthermore, the latencies seem to be a more sensitive indicator for ICF action than the size parameters of motor evoked potentials. 相似文献
19.
Azulenes as Dienophiles in the [4+2]-Cycloaddition with Inverse Electron Demand, a Supplement [4+2] Cycloadditions of azulene ( 2 ) und 1-Nitroazulene ( 14 ) with the extremely electron-deficient, s-cis-fixed diazadiene system of 3,6-bis(trifluoromethyl)-1,2,4,5-tetrazine ( 1 ) are described. In addition to earlier findings 1 reacts with 2 probably in a two step [4+2] cycloaddition via 8 and 10 to yield the benzo[f]phthalazine 5a , via 8 and 9 to furnish the azuleno[d]pyridazine 3 and the azine 4 . The reaction of 1 with 1-Nitroazulene ( 14 ) leads to the azuleno[d]pyridazines 3 and 19 in low yield. 相似文献
20.