This study investigated the possible relationship between the invasiveness of group A
Streptococcus (GAS) strains and their abilities to adhere to
laminin and assessed the effects of subinhibitory concentrations of penicillin and
erythromycin on the ability of GAS to adhere to laminin. The adherence of noninvasive
and highly invasive isolates of GAS to laminin was significantly higher than the
adherence displayed by isolates of low invasiveness. Antibiotic treatment caused
significant reductions in adherence to laminin in all three groups of strains.
Penicillin was more successful in reducing the adherence abilities of the tested GAS
strains than erythromycin. 相似文献
Because of their photo-optical distinctiveness and biocompatibility, gold nanoparticles have proven to be powerful tools in various nanomedical applications. In this article, we discuss the advantage of gold nanoparticles in image diagnostic application of melanoma. It has demonstrated the potential role of gold nanoparticles in the study of tumour tissue architecture and the utility of gold nanoparticles in the hystopathological exam of B16 melanoma with the benefit of fluorescence emission of gold nanoparticles in UV spectrum. The optical properties of colloidal gold nanoparticles allow spectroscopic detection and identification of melanoma cells. The method proposed is easy, inexpensive and reliable for hystopathological analysis of melanoma. The fluorescence images in the cryosections of tissues depicted a strong luminescence property of gold nanoparticles uptaken in melanoma, results that confirm the role of the gold nanoparticles in biological labelling and imaging applications. To emphasize the AuNPs influence over the biological tissues, a study of the chemical bonds configuration was performed using Raman spectrometry. 相似文献
Chromosome segregation depends on sister chromatid cohesion which is established by cohesin during DNA replication. Cohesive cohesin complexes become acetylated to prevent their precocious release by WAPL before cells have reached mitosis. To obtain insight into how DNA replication, cohesion establishment and cohesin acetylation are coordinated, we analysed the interaction partners of 55 human proteins implicated in these processes by mass spectrometry. This proteomic screen revealed that on chromatin the cohesin acetyltransferase ESCO2 associates with the MCM2‐7 subcomplex of the replicative Cdc45‐MCM‐GINS helicase. The analysis of ESCO2 mutants defective in MCM binding indicates that these interactions are required for proper recruitment of ESCO2 to chromatin, cohesin acetylation during DNA replication, and centromeric cohesion. We propose that MCM binding enables ESCO2 to travel with replisomes to acetylate cohesive cohesin complexes in the vicinity of replication forks so that these complexes can be protected from precocious release by WAPL. Our results also indicate that ESCO1 and ESCO2 have distinct functions in maintaining cohesion between chromosome arms and centromeres, respectively. 相似文献
Due to the increasing economic and social relevance of biotherapeutics, their production processes are continually being reconsidered and reoptimized in an effort to secure higher product concentrations and qualities. Monitoring the productivity of cultured cells is therefore a critically important part of the cultivation process. Traditionally, this is achieved by determining the overall product titer by high performance liquid chromatography (HPLC), and then calculating the specific cell productivity based on this titer and an associated viable cell density. Unfortunately, this process is typically time‐consuming and laborious. In this study, the productivity of Chinese Hamster Ovary (CHO) cells expressing a monoclonal antibody was analyzed over the course of the cultivation process. In addition to calculating the specific cell productivity based on the traditional product titer determined by HPLC analysis, culture productivity of single cells was also analyzed via flow cytometry using a cold capture assay. The cold capture assay is a cell surface labelling technique described by Brezinsky et al., which allows for the visualization of a product on the surface of the producing cell. The cell productivity results obtained via HPLC and the results of cold capture assay remained in great accordance over the whole cultivation process. Accordingly, our study demonstrates that the cold capture assay offers an interesting, comparatively time‐effective, and potentially cheaper alternative for monitoring the productivity of a cell culture. 相似文献
Sustained pain relief following radon spa therapy in patients suffering from chronic painful diseases has been well described. But still, the underlying mechanisms are not fully understood. We conducted the prospective and explorative RAD-ON01 study which included 103 patients who suffered from chronic painful musculoskeletal disorders of the spine and/or joints and present here the data of the examination of pro- and anti-inflammatory cytokines in the serum of the patients before and at weeks 6, 12 and 30 after therapy. While TNFα, IL-1β, IFNγ, IL-1Ra and IL-10 were not altered, TGFβ was temporarily significantly (p = 0.013) elevated 6 weeks after therapy. Importantly, this elevation positively correlated with lowered pain sensitivity (r = 0.41). Further, the amount of IL-18 in the serum positively correlated with lowered pain sensitivity. Therefore, IL-18 can be considered as predictive marker for pain sensitivity of radon spa patients. We conclude that alterations in TGFβ and general IL-18 levels in serum have prognostic and predictive value in situations of lowered pain by exposure of patients to very low-doses of radiation as it is the case in radon spa.