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1.
E. Töpfer-Petersen A. E. Friess M. Stoffel W.-B. Schill 《Histochemistry and cell biology》1990,93(5):485-490
Summary A monoclonal antibody, designated mAb P86/5, was generated by immunization of female Balb/c mice with a membrane vesicle fraction composed of the outer acrosomal membrane and plasma membrane (PM-OAM). As determined by fluorescence microscopy and electron microscopy P86/5 recognizes a sperm plasma membrane antigen that is restricted to the sperm head. In intact spermatozoa the P86/5-antigen is distributed over the surface of the sperm head with the exception of the rostral region. By comparing the antibody binding pattern generated at 4° C and 25° C, it could be shown that the P86/5-antigen is capable to diffuse freely within the cell membrane overlying the acrosome whereas its lateral mobility is restricted to the post-acrosomal region. The P86/5-antigen had a molecular weight of about 78 kDa as revealed by SDS-PAGE and western blotting. The glycoprotein nature of the P86/5-antigen was established by lectin affinity chromatography. 相似文献
2.
Tara?C.?Mueller Rebekka?Schirren Victoria?Kehl Helmut?Friess Daniel?ReimEmail author Marc?E.?Martignoni 《Trials》2017,18(1):621
Background
The majority of patients with gastric or esophago-gastric cancer are at risk for malnutrition. Preoperative malnutrition was shown to increase the incidence of postoperative complications following abdominal surgery. However, it remains unclear if preoperative parenteral nutritional support during neoadjuvant chemotherapy (NACT) may be effective to reduce the rate of postoperative complications in these patients.Methods/Design
The PERCOG trial is a randomized controlled multicenter observer-blinded trial, investigating if the improvement of the general condition of patients with non-metastasized gastric cancer or cancer of the esophago-gastric junction during NACT by supplemental parenteral nutrition can decrease the postoperative Comprehensive Complication Index (CCI). Statistical analysis of the primary endpoint measure (CCI on postoperative day 30) will be based on the intention-to-treat population. The global level of significance is set at 5% and the sample size (n?=?150) is determined to assure a power of 80%.Discussion
The results of the PERCOG trial will provide high-level evidence for clinical recommendations regarding the administration of preoperative supportive parenteral nutrition and provide all participating patients the opportunity of an improved treatment.Trial registration
German Clinical Trials Register, DRKS00009451. Registered on 3 July 2017.3.
In this study we have examined the behaviour and the localization of the fucose-binding protein (FBP) in boar spermatozoa during ionophore induced acrosome reaction (AR) by means of normal TEM and specimen preparation in toto. During early stages of AR the FBP is first localized at the border between equatorial segment and anterior acrosome. With the propagation of the AR the FBP is dramatically expressed and visible over the entire surface of the acrosome and equatorial segment. TEM pictures of this stages show that the FBP is associated with the OAM. At later stages of AR, when acrosomal ghost formation occur, the FBP is associated with the acrosomal ghost, and equatorial segment and to a very low degree also with the IAM. It is concluded from this data that the FBP is responsible for the specific binding of the ghost-sperm unit to the zona pellucida. 相似文献
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5.
Li J Kleeff J Kayed H Felix K Penzel R Büchler MW Korc M Friess H 《Biochemical and biophysical research communications》2004,320(4):1148-1155
The heparan sulfate proteoglycan glypican-1 is essential as a co-receptor for heparin binding growth factors, such as HB-EGF and FGF-2, in pancreatic cancer cells. In the present study, the role of glypican-1 in the regulation of TGF-beta signaling was investigated. Colo-357 pancreatic cancer cells were stably transfected with a full-length glypican-1 antisense construct. Cell growth was determined by MTT and soft agar assays. TGF-beta1 induced p21 expression and Smad2 phosphorylation were analyzed by immunoblotting. PAI-1 promoter activity was determined by luciferase assays. Down-regulation of glypican-1 expression by stable transfection of a full-length glypican-1 antisense construct resulted in decreased anchorage-dependent and -independent cell growth in Colo-357 pancreatic cancer cells and attenuated TGF-beta1 induced cell growth inhibition, Smad2 phosphorylation, and PAI-1 promoter activity. There was, however, no significant difference in TGF-beta1 induced p21 expression and Smad2 nuclear translocation. In conclusion, glypican-1 is required for efficient TGF-beta1 signaling in pancreatic cancer cells. 相似文献
6.
Christoph W Michalski Fabio Francesco Di Mola Klaus Kümmel Michael Wendt J?rg S K?ninger Thomas Giese Nathalia A Giese Helmut Friess 《BMC microbiology》2006,6(1):81
Background
There is increasing evidence that bacterial infection of the intestinal mucosa may contribute to the pathogenesis of inflammatory bowel diseases (IBD). In pigs, an obligate intracellular bacterium, Lawsonia intracellularis (LI), was shown to cause proliferative enteropathy (PE) of which some forms display histological and clinical similarities to human IBD. Since LI-similar Desulfovibrio spp. may infect human cells, we hypothesized that LI might be associated with the development of human IBD. 相似文献7.
Arno Kornberg Ulrike Witt Jennifer Kornberg Katharina Müller Helmut Friess Katharina Thrum 《Biomarkers》2016,21(2):152-159
Context: C-reactive protein (CRP), a biomarker of inflammation, may correlate with prognosis in several malignancies.Objective: To investigate the prognostic impact of early postoperative peak serum levels of CRP on tumor-specific outcome in 106 liver transplant patients with hepatocellular carcinoma (HCC).Methods and results: In multivariate Cox regression analysis, a posttransplant elevated peak CRP level (>versus?≤?3.5?mg/dl) was identified as an independent predictor of poor recurrence-free survival (p?=?0.01; HR?=?4.04; CI?=?1.399–11.640).Conclusion: Early postoperative serum CRP may serve as a useful inflammation-based biomarker of outcome in liver transplant patients with HCC. 相似文献
8.
F. Töpfer-Petersen A. E. Friess H. Nguyen W. -B. Schill 《Histochemistry and cell biology》1985,83(2):139-145
Summary A fucose binding, protein was detected in boar spermatozoa by means of a specifically developed modified enzyme-linked-lectin-assay using glycosylated peroxidase derivatives. The distribution of the fucose binding protein was assessed by means of fluorescence microscopy with fluoresceinyl-glycosylated peroxidase. Fucose binding was particularly prominent at the apical region of the sperm head. In order to gain more insight into the precise localization of the carbohydrate binding, protein electron microscopical studies were performed using fucosyl peroxidase coupled to colloidal gold. In ultrathin sections as well as in specimens, prepared in toto for TEM an intensive binding of fucosylperoxidase-colloidal gold was predominantly found at the apical part of the acrosome appearing as a crescent-like area. In some cases this binding pattern was replaced by a triangle-like intensive labelling at the equatorial segment as revealed clearly by specimens prepared in toto. By SDS-PAGE of the SDS-extractable sperm-proteins, followed by transblotting to nitrocellulose and visualization with the fucosylperoxidase by enzymatic amplification with 4-chloro-1-naphthol mainly one protein with the reduced molecular weight of approximately 53 kdal and some small proteins with apparent molecular weights less than 20 kdal was found to be responsible for the fucose-binding ability of porcine spermatozoa. 相似文献
9.
10.
Hernández-Cruz AE E Sánchez P Preciado-Rangel M L García-Bañuelos A Palomo-Gil A Espinoza-Banda 《Phyton》2015,84(2):454-460
In the production of cotton (Gossypium hirsutum L.), nitrogen fertilization is one of the most costly crop practices, but important to reach high yields. However, high nitrogen (N) content in plants does not always translate into a high fibre production. One way of assessing the efficiency of the N fertilizer is through the enzymatic activity of the nitrate reductase (NR). This is a key enzyme in N assimilation, whose activity is regulated by a number of endogenous and exogenous factors that determine yield. The aim of this study was to assess the effect of N fertilization on yield, fibre quality, biomass, and NR enzymatic activity in vivo in the cotton variety Fiber Max 989. The evaluated application rates were 0, 50, 100, and 150 kg/ha of N, using urea as a source (46% N) in a randomizedblock design with three replicates. At harvest, the maximum yield of seed cotton and the greatest accumulation of total foliar biomass through time was reached after applying 150 kg N/ha. The different N-application rates did not affect the components of cotton-fibre quality. The activity of endogenous NR was greater on plants where 150 kg N/ha were applied. The highest cotton yield and N contents were obtained on these plants. Therefore, the NR activity in vivo could be used as a bioindicator of the N nutritional level in cotton. 相似文献