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Vezatin, a ubiquitous protein of adherens cell-cell junctions, is exclusively expressed in germ cells in mouse testis 总被引:1,自引:0,他引:1
Hyenne V Harf JC Latz M Maro B Wolfrum U Simmler MC 《Reproduction (Cambridge, England)》2007,133(3):563-574
In the male reproductive organs of mammals, the formation of spermatozoa takes place during two successive phases: differentiation (in the testis) and maturation (in the epididymis). The first phase, spermiogenesis, relies on a unique adherens junction, the apical ectoplasmic specialization linking the epithelial Sertoli cells to immature differentiating spermatids. Vezatin is a transmembrane protein associated with adherens junctions and the actin cytoskeleton in most epithelial cells. We report here the expression profile of vezatin during spermatogenesis. Vezatin is exclusively expressed in haploid germ cells. Immunocytochemical and ultrastructural analyses showed that vezatin intimately coincides, temporally and spatially, with acrosome formation. While vezatin is a transmembrane protein associated with adherens junctions in many epithelial cells, it is not seen at the ectoplasmic specializations, neither at the basal nor at the apical sites, in the seminiferous epithelium. In particular, vezatin does not colocalize with espin and myosin VIIa, two molecular markers of the ectoplasmic specialization. In differentiating spermatids, ultrastructural data indicate that vezatin localizes in the acrosome. In epididymal sperm, vezatin localizes also to the outer acrosomal membrane. Considering its developmental and molecular characteristics, vezatin may be involved in the assembly/stability of this spermatic membrane. 相似文献
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M.Sc. Branca Delmonte Dr.-Ing. Sebastian Latz M.Sc. Jules Youmbi Prof. Dr.-Ing. Stefan Maas 《Bauphysik》2024,46(1):1-10
For decades efforts have been made to reduce the greenhouse gases emissions of buildings by reducing their energy demand with governmental regulations in Europe, pushing towards very low thermal transmittances (U-values) with ever thicker insulation layers for new buildings. However, there is no linear relationship between the insulation thickness and the heat losses. Therefore, above a certain thickness the consumption of buildings does not decrease significantly. Hereafter a life cycle analysis, including emissions before the building becomes operational is applied to evaluate the impact of the increasing thickness of components on the overall emissions. Publicly available product data sheets are used to compare four insulation materials under three scenarios. These analyses yield interesting results showing that energy-intensive insulation materials lead to a negative impact in the overall energy balance after a certain thickness. Even though there is not always a pronounced optimum insulation thickness, it is logical that further reductions in U-value for new buildings should hence be carefully evaluated. The results show that the optimal thickness is around 20 cm for most materials, while the important major savings come from the first 10 cm. 相似文献
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In a retrospective study of 1126 children with fractures of the proximal third of the femur, three children were found to have isolated fractures of the lesser trochanter. This fracture occurred from a fall in one child and following sporting activities, without a history of injury, in the others. In the latter children, the clinical presentations were similar to those of children with transient synovitis of the hip or Perthes disease. In each child, plain radiographs showed an avulsion fracture of the bony portion of the lesser trochanter. Early and complete recovery followed symptomatic treatment even when there was marked proximal displacement of the avulsed segment of the lesser trochanter. 相似文献
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In recent reports of the so-called "floral variant" of follicular lymphoma, an unusual variant of follicular lymphoma mimicking progressive transformation of germinal centers, questions have been raised regarding whether this process represents a malignant lymphoma. We studied 19 examples of the floral variant of follicular lymphoma and report our light microscopic, immunohistochemical, and molecular diagnostic findings. Morphologic changes consisted of effacement of normal lymph node architecture by follicles composed of atypical lymphocytes. The follicles were surrounded by prominent mantle zones that invaginated irregularly into the follicle centers, often imparting a "floral" appearance. Sufficient material was available for immunophenotypic or genotypic studies in 15 biopsies. Twelve of 15 cases studied by immunohistochemistry demonstrated phenotypes supporting a diagnosis of lymphoma. Five demonstrated light-chain restriction; one was an immunoglobulin-negative B-cell neoplasm; and six, in which only formalin-fixed, paraffin-embedded tissue was available, demonstrated overexpression of the bcl-2 protein. Southern blot analysis revealed evidence of clonal immunoglobulin heavy-chain gene rearrangement in all five cases tested. Overall, 12 of the 15 biopsies studied with these techniques showed immunologic or genotypic support for malignant lymphoma. The results of this study demonstrate that the floral variant of follicular lymphoma does indeed represent a malignant lymphoma. 相似文献
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Shruthi Thada Gabor L. Horvath Mario M. Müller Nickel Dittrich Melanie L. Conrad Saubashya Sur Abid Hussain Karin Pelka Suman Latha Gaddam Eicke Latz Hortense Slevogt Ralf R. Schumann Sanne Burkert 《International journal of molecular sciences》2021,22(4)
The interaction and crosstalk of Toll-like receptors (TLRs) is an established pathway in which the innate immune system recognises and fights pathogens. In a single nucleotide polymorphisms (SNP) analysis of an Indian cohort, we found evidence for both TLR4-399T and TRL8-1A conveying increased susceptibility towards tuberculosis (TB) in an interdependent manner, even though there is no established TLR4 ligand present in Mycobacterium tuberculosis (Mtb), which is the causative pathogen of TB. Docking studies revealed that TLR4 and TLR8 can build a heterodimer, allowing interaction with TLR8 ligands. The conformational change of TLR4-399T might impair this interaction. With immunoprecipitation and mass spectrometry, we precipitated TLR4 with TLR8-targeted antibodies, indicating heterodimerisation. Confocal microscopy confirmed a high co-localisation frequency of TLR4 and TLR8 that further increased upon TLR8 stimulation. The heterodimerisation of TLR4 and TLR8 led to an induction of IL12p40, NF-κB, and IRF3. TLR4-399T in interaction with TLR8 induced an increased NF-κB response as compared to TLR4-399C, which was potentially caused by an alteration of subsequent immunological pathways involving type I IFNs. In summary, we present evidence that the heterodimerisation of TLR4 and TLR8 at the endosome is involved in Mtb recognition via TLR8 ligands, such as microbial RNA, which induces a Th1 response. These findings may lead to novel targets for therapeutic interventions and vaccine development regarding TB. 相似文献
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Lukas Polte Lukas Raßpe-Lange Filip Latz Prof. Dr.-Ing. Andreas Jupke Prof. Dr. rer. nat. Kai Leonhard 《化学,工程师,技术》2023,95(3):416-426
For an extraction process to be economically feasible, selecting a suitable solvent is imperative. This work extends the computer-aided molecular and process design (CAMPD) framework COSMO-CAMPD for solvent design in an extraction-distillation process by replacing a pinch-based process model with a hybrid, rate-based extraction-distillation process model. The resulting CAMPD framework is able to evaluate solvent candidates by investment costs in addition to operating costs in a fully predictive manner. In a case study for purifying acetone, we show that our framework's guided exploration of a vast design space yields solvents with superior performance compared to a benchmark solvent from the literature. 相似文献
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C Wilimzig R Latz W Vierling E Mutschler T Trnovec S Nyulassy 《Canadian Metallurgical Quarterly》1996,49(4):317-323
The distal metatarsal osteotomy according to Magerl allows correction of a hallux valgus deformity by lateral and plantar displacement as well as by pronation and variasation. The length of the first metatarsal can be adjusted by the depth of the cut at the resection or by a slightly oblique osteotomy. If necessary, soft tissue release and/or a osteotomy of the first proximal phalanx can be done to relocate the sesamoids under the head of the first metatarsal. A review of 118 foot operations in 75 patients demonstrated a very good or good result in about 75%. Radiological examination showed sufficient lateralisation of the metatarsal head. Evaluating the length of the first metatarsal and the amount of variation, the results were less satisfying. The metatarsophalangeal angles could be corrected by 14 degrees and the intermetatarsal angles by 7 degrees on average. The sophisticated operative procedure limits the use of this technique as a standard procedure. 相似文献