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41.
In developing muscle cells environmental stimuli transmitted by purines binding to the specific receptors are crucial proliferation regulators. C2C12 myoblasts express numerous purinergic receptors representing both main classes: P2X and P2Y. Among P2Y receptors we have found the expression of P2Y(1), P2Y(2), P2Y(4), P2Y(6) and P2Y(12) family members while among P2X receptors P2X(4), P2X(5) and P2X(7) were discovered. We have been able to show that activation of those receptors is responsible for ERK class kinase activity, responsible for regulation of cell proliferation pathway. We have also demonstrated that this activity is calcium dependent suggesting Ca(2+) ions as secondary messenger between receptor and kinase regulatory system. More specifically, we do suspect that in C2C12 myoblasts calcium channels of P2X receptors, particularly P2X(5) play the main role in proliferation regulation. In further development of myoblasts into myotubes, when proliferation is gradually inhibited, the pattern of P2 receptors is changed. This phenomenon is followed by diminishing of the P2Y(2)-dependent Ca(2+) signaling, while the mRNA expression of P2Y(2) receptor reminds still on the high level. Moreover, P2X(2) receptor mRNA, absent in myoblasts appears in myotubes. These data show that differentiation of C2C12 cell line satellite myoblasts is accompanied by changes in P2 receptors expression pattern.  相似文献   
42.

Introduction

Amplification of the ESR1 gene, coding for estrogen receptor alpha, was shown to predict responsiveness to tamoxifen, however its prognostic impact in breast cancer patients has not been thoroughly investigated. Other factors that could contribute to responsiveness to tamoxifen treatment are polymorphisms in ESR1 gene and genes involved in tamoxifen metabolism.The aim of this study was to assess the prognostic role of ESR1 gene dosage in a consecutive group of breast cancer patients and to correlate this feature with clinico-pathological factors. Additionally, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphisms were analyzed in the tamoxifen-treated subgroup of patients.

Materials and Methods

Primary tumor samples from 281 stage I-III consecutive breast cancer patients were analyzed for ESR1 gene dosage using real-time PCR with locked nucleic acids hydrolysis probes. In the tamoxifen-treated subgroup of patients, ESR1 PvuII, CYP2C19*2 and UGT2B15*2 polymorphism in leukocytes genomic DNA were analyzed. Results were correlated with clinico-pathological factors and with disease-free survival (DFS) and overall survival (OS).

Results

ESR1 amplification (with a cut-off level of 2.0) was found in 12% of the entire group of breast cancer patients, and in 18% of the ER-negative subgroup. This feature was associated with decreased DFS both in the entire group (P=0.007) and in the ER-negative subgroup (P=0.03), but not in the tamoxifen-treated patients.Patients with ESR1 PvuII wt/wt genotype and at least one UGT2B15 wt allele had a worse DFS (P=0.03) and showed a trend towards decreased Os (P=0.08) in comparison to patients with ESR1 PvuII wt/vt or vt/vt genotype and UGT2B15 *2/*2 genotype.

Conclusions

ESR1 amplification can occur in ER-negative tumors and may carry poor prognosis. In the tamoxifen-treated subgroup, poor prognosis was related to the combined presence of ESR1 PvuII wt/wt and UGT2B15wt/wt or wt/*2 genotype.  相似文献   
43.
Bacterial chromosome segregation usually involves cytoskeletal ParA proteins, ATPases which can form dynamic filaments. In aerial hyphae of the mycelial bacterium Streptomyces coelicolor, ParA filaments extend over tens of microns and are responsible for segregation of dozens of chromosomes. We have identified a novel interaction partner of S. coelicolor ParA, ParJ. ParJ negatively regulates ParA polymerization in vitro and is important for efficient chromosome segregation in sporulating aerial hyphae. ParJ-EGFP formed foci along aerial hyphae even in the absence of ParA. ParJ, which is encoded by sco1662, turned out to be one of the five actinobacterial signature proteins, and another of the five is a ParJ paralogue. We hypothesize that polar growth, which is characteristic not only of streptomycetes, but even of simple Actinobacteria, may be interlinked with ParA polymer assembly and its specific regulation by ParJ.  相似文献   
44.
Daughter yield deviations (DYDs) of bulls and yield deviations (YDs) of cows, besides estimated breeding values (EBVs), are standard measures of animals' genetic merits in routine genetic evaluations worldwide. In this contribution, we first point out differences and similarities between DYDs and EBVs calculated for milk, fat and protein yields. While the latter measure represents the additive polygenic value of an animal, the former consists of both the additive polygenic and residual components. Then, a summary of DYDs and YDs calculated for the Polish population of dairy cattle is presented. The estimated correlations between DYDs and EBVs are generally high, but vary considerably depending on the minimum number of daughters used for calculation of DYDs and on the accuracy of calculated DYDs. Using DYDs estimated for each production year for 16 452 bulls, we demonstrate how to use DYDs for the validation of genetic trend estimated in the model used for genetic evaluation. Based on genotypic data of 252 bulls, we show that DYDs can be used for the estimation of candidate gene effects. For each of the yield traits, the within-bull genetic trend was relatively high, ranging between 1.39% of genetic standard deviation per production year for milk and 7.67% of genetic standard deviation per production year for fat, both in the 2nd lactation. Out of 8 polymorphisms tested, 5 showed a significant correlation with DYD, with the highest effect attributed to the polymorphism within the leptin receptor gene, whose additive effect was estimated as 247.33 kg of milk at 2nd parity.  相似文献   
45.
The covalent conjugate of oligosaccharide core of Escherichia coli type R4 with tetanus toxoid was prepared using reaction of reductive amination. The neoglycoconjugate was a good immunogen in rabbits yielding a high level of anti-lipopolysaccharide (LPS) antibodies of the IgG class. It was found that antiserum was able to react with the smooth LPS molecules of identical (R4) or related (R1) core type. The reactions were shown in the enzyme-linked immunosorbent assay and the immunoblotting test. Flow cytometry showed that anti-core antibodies reacted with LPS present on intact, live, smooth bacteria labelling more than 90% of cells. The anti-OS R4-TT serum used for in vitro studies showed high endotoxin neutralization activity. The serum inhibited endotoxin-induced tumor necrosis factor alpha and nitric oxide synthesis by the J-774A.1 cell line and attenuated pulmonary retention of YAC-1 cells.  相似文献   
46.
Obesity and endocrine disorders have become prevalent issues in the field of both human and veterinary medicine. Equine metabolic syndrome is a complex disorder involving alternation in metabolism and chronic systemic inflammation. It has been shown that unfavourable microenvironment of inflamed adipose tissue negatively affects adipose stem cell population (ASC) residing within, markedly limiting their therapeutic potential. ASCsEMS are characterized by increased senescence apoptosis, excessive accumulation of reactive oxygen species (ROS), mitochondria deterioration and “autophagic flux.” The aim of the present study was to evaluate whether treatment of ASCsEMS with a combination of 5‐azacytydine (AZA) and resveratrol (RES) would reverse aged phenotype of these cells. For this reason, we performed the following analyzes: molecular biology (RT‐PCR), microscopic (immunofluorescence, TEM) and flow cytometry (JC‐1, ROS, Ki67). We evaluated the mitochondrial status, dynamics and clearance as well as autophagic pathways. Furthermore, we investigated epigenetic alternations in treated cells by measuring the expression of TET genes and analysis of DNA methylation status. We have demonstrated that AZA/RES treatment of ASCsEMS is able to rejuvenate these cells by modulating mitochondrial dynamics, in particular by promoting mitochondrial fusion over fission. After AZA/RES treatment, ASCsEMS were characterized by increased proliferation rate, decreased apoptosis and senescence and lower ROS accumulation. Our findings offer a novel approach and potential targets for the beneficial effects of AZA/RES in ameliorating stem cell dysfunctions.  相似文献   
47.
48.
Marine cyanobacteria are noted for their ability to excrete metabolites with biotic properties. This paper focuses on such exometabolites obtained from the culture of the marine filamentous cyanobacterium Geitlerinema sp. strain, their purification and subsequent analyses. By this means the recoveries of the active compounds, a prerequisite for properly determining their concentration, are quantified here for the first time. We demonstrate a new procedure using Amberlite XAD-1180 resin in combination with the eluent isopropanol for extraction of the culture media and gas chromatography as simplified chemical analysis. This procedure reduced necessary bacteria cultivation time (from 150 to 21?days) at low volumes of culture media (300?mL) required for identification of two selected bioactive compounds: 4,4'-dihydroxybiphenyl and harmane.  相似文献   
49.
Antiproliferative and antifungal activities of essential oils from Erigeron acris root and herb and from Erigeron annuus herb were investigated. The cell viability assay was performed in cultured fibroblasts, cancer cell lines (MCF-7 and MDA-MBA-231), and endometrial adenocarcinoma (Ishikawa) cells as well as colon adenocarcinoma (DLD-1) cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The essential oil from E. acris root showed the highest antiproliferative activity in the MCF-7 cell line with an IC50 value of 14.5 microg/mL. No effect of the essential oil on normal cells at that concentration was found. Antifungal activity against various strains of five Candida species, i.e. C. albicans, C. glabrata, C. tropicalis, C. krusei, and C. parapsilosis, was tested by the microdilution method. It was found that all examined oils can be useful as antifungal agents against the above-mentioned species, but the essential oil of E. acris herb was the most active. Their minimum inhibitory concentrations (MIC) ranged from 30 to 0.4 microL/mL. The data presented suggest that essential oils from E. acris and E. annuus possess antifungal activity against Candida spp. and antiproliferative activity against breast cancer MCF-7 cells.  相似文献   
50.
The purpose of this study was to analyze and compare genes encoding superantigens (SAgs) in Staphylococcus xylosus and Staphylococcus aureus isolates collected simultaneously from milk of the same cows with clinical mastitis. Genes encoding staphylococcal enterotoxins and enterotoxin-like proteins (sea-selu), toxic shock syndrome toxin 1 (tst-1) and exfoliative toxins (eta and etd) were investigated. It was found that among 30 isolates of S. xylosus, 16 (53.3%) harbored from 1 to 10 SAg genes. In total, in 16 SAg positive S. xylosus, 11 different enterotoxin genes were detected: sec, sed, seg, seh, sei, selm, seln, selo, selp, ser, selu and one etd gene encoding exfoliative toxin D. The most prevalent genes were ser, selu, and selo. Among all the positive isolates of S. xylosus, a total of 14 different SAg gene combinations were detected. One combination was repeated in 3 isolates, whereas the rest were detected only once. However, in the case of S. aureus all the 30 isolates harbored the same combination of SAg genes: seg, sei, selm, seln, selo and on the basis of PFGE analysis all belonged to the same clonal type. Also noteworthy was the observation that SAg genes detected in S. aureus have also been found in S. xylosus. The findings of this study further extend previous observations that SAg genes are present not only in S. aureus but also in coagulase-negative staphylococci, including S. xylosus. Therefore, taking into account that the SAg genes are encoded on mobile genetic elements it is possible that these genes can be transferred between different species of coexisting staphylococci.  相似文献   
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