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101.
The role of CD28- T cell subpopulations in primary Sj?gren's syndrome (pSS) has become controversial. Changes in the number of CD28- T cells have been demonstrated in autoimmune diseases in co-existence with Sj?gren's syndrome. The study aimed to indicate differences in the number of CD4+CD28- and CD8+CD28- T cells in patients with sicca syndrome and suspected pSS. Thirty patients with sicca syndrome at baseline were studied and followed up for 5months. After final diagnosis, comparison was made of the previously recorded lymphocyte subpopulations in patients with pSS and those in other defined subgroups. Notably high percentages of CD8+CD28- T cells were indicated in pSS patients, which correlated with the severity of the sicca symptoms and cutaneous and muscular systemic disease activity. Changes in CD8+CD28- T cell percentages may thus assist in the early differential diagnosis of pSS patients from those with similar clinical symptoms. 相似文献
102.
Dolińska B Zieliński M Dobrzański Z Chojnacka K Opaliński S Ryszka F 《Biological trace element research》2012,147(1-3):354-358
The influence of incubation conditions, enzyme type, hydrolysis time, and potassium iodide concentration on hydrolysis and iodine enrichment were studied in supernatant and pellets of Saccharomyces cervisiae hydrolysates. The type of enzyme used and incubation time significantly influence hydrolysis efficiency and protein concentration in supernatant and pellet. The highest protein hydrolysis efficiency was obtained by 24-h incubation with papain. Significantly lower values were observed for pepsin and autolysis. The potassium iodide concentration influences the iodine content of supernatant and pellet, but not hydrolysis. Iodide enrichment of supernatant and pellet depends on the concentration of iodide using during incubation. High concentration of iodide and long incubation times were the conditions for optimal iodide enrichment and high-protein hydrolysates. The optimal hydrolysis efficiency and iodine enrichment were obtained during 24-h incubation with papain in a 4.5-mM potassium iodide medium. The efficiency reached 98.22% with iodine concentrations of 2,664.91 and 9,200.67 μg/g iodine in pellet and supernatant, respectively. 相似文献
103.
Stelmanska E Kmiec Z Swierczynski J 《The Journal of steroid biochemistry and molecular biology》2012,132(1-2):160-167
Progesterone affects lipid metabolism in adipose tissue and influences fat distribution in human. The aim of the study was to analyze the effect of progesterone on rat body and fat mass and on expression of genes encoding adipokines involved in the regulation of energy homeostasis. The results presented here indicate that progesterone administration to females caused increase in body and inguinal white adipose tissue mass. The increase of inguinal white adipose tissue mass is associated with the hypertrophy of adipocyte. The same dose of progesterone caused increase of its circulating concentration in males, however it barely reached the value observed in non-treated control females and did not have any effect on body and fat mass. The elevated circulating progesterone concentration was associated with an approximately 6- and 2-fold increase of leptin and resistin mRNA level respectively, and 2-fold decrease of adiponectin mRNA level only in inguinal white adipose tissue of females. RU 486, specific antagonist of progesterone receptor, abolished the effect of progesterone on the adipokine mRNA level in inguinal adipose tissue. In males, the elevated circulating progesterone concentration showed no effects on leptin, resistin or adiponectin mRNA level in inguinal, retroperitoneal or epididymal adipose tissue. Moreover, the results presented in this paper demonstrate a relatively high level of progesterone receptor mRNA in inguinal white adipose tissue of females, which was down-regulated in response to progesterone administration. In retroperitoneal adipose tissue of control females progesterone receptor mRNA level was approximately 3-fold lower as compared to inguinal adipose tissue. In inguinal, epididymal and retroperitoneal white adipose tissue of males progesterone receptor mRNA was hardly detected. Our results suggest that depot- and sex-dependent responsiveness of adipose tissue to the pharmacological dose of progesterone is controlled by both circulating concentration of progesterone and the white adipose tissue progesterone receptor level. 相似文献
104.
Zbigniew Starosolski Marek Szczepanski Manuel Wahle Mirabela Rusu Willy Wriggers 《Biophysical reviews》2012,4(3):223-229
The low radiation conditions and the predominantly phase-object image formation of cryo-electron microscopy (cryo-EM) result in extremely high noise levels and low contrast in the recorded micrographs. The process of single particle or tomographic 3D reconstruction does not completely eliminate this noise and is even capable of introducing new sources of noise during alignment or when correcting for instrument parameters. The recently developed Digital Paths Supervised Variance (DPSV) denoising filter uses local variance information to control regional noise in a robust and adaptive manner. The performance of the DPSV filter was evaluated in this review qualitatively and quantitatively using simulated and experimental data from cryo-EM and tomography in two and three dimensions. We also assessed the benefit of filtering experimental reconstructions for visualization purposes and for enhancing the accuracy of feature detection. The DPSV filter eliminates high-frequency noise artifacts (density gaps), which would normally preclude the accurate segmentation of tomography reconstructions or the detection of alpha-helices in single-particle reconstructions. This collaborative software development project was carried out entirely by virtual interactions among the authors using publicly available development and file sharing tools. 相似文献
105.
Mazurek M Kowalczyk J Lenarczyk R Zielinska T Sedkowska A Pruszkowska-Skrzep P Swiatkowski A Sredniawa B Kowalski O Polonski L Strojek K Kalarus Z 《Cardiovascular diabetology》2012,11(1):78
ABSTRACT: BACKGROUND: Diabetes (DM) deteriorates the prognosis in patients with coronary heart disease. However, the prognostic value of different glucose abnormalities (GA) other than DM in subjects with acute myocardial infarction (AMI) treated invasively remains unclear. AIMS: To assess the incidence and impact of GA on clinical outcomes in AMI patients treated with percutaneous coronary intervention (PCI). METHODS: A single-center, prospective registry encompassed 2733 consecutive AMI subjects treated with PCI. In all in-hospital survivors (n = 2527, 92.5 %) without the history of DM diagnosed before or during index hospitalization standard oral glucose tolerance test (OGTT) was performed during stable condition before hospital discharge and interpreted according to WHO criteria. The mean follow-up period was 37.5 months. RESULTS: The incidence of GA was as follows: impaired fasting glycaemia - IFG (n = 376, 15 %); impaired glucose tolerance - IGT (n = 560, 22 %); DM (n = 425, 17 %); new onset DM (n = 384, 15 %); and normal glucose tolerance NGT (n = 782, 31 %). During the long-term follow-up, death rate events for previously known DM, new onset DM and IGT were significantly more frequent than those for IFG and NGT (12.3; 9.6 and 9.4 vs. 5.6 and 6.4 %, respectively, P < 0.05). The strongest and common independent predictors of death in GA patients were glomerular filtration rate < 60 ml/min/1,73 m^2 (HR 2.0 and 2.8) and left ventricle ejection fraction < 35 % (HR 2.5 and 1.8, all P < 0.05) respectively. CONCLUSIONS: Glucose abnormalities are very common in AMI patients. DM, new onset DM and IGT increase remote mortality. Impaired glucose tolerance bears similar long-term prognosis as diabetes. 相似文献
106.
Anna Krupa Renata Jachowicz Zbigniew P?dzich Krystyna Wodnicka 《AAPS PharmSciTech》2012,13(4):1120-1129
Directly compressible co-processed excipient systems facilitate orodispersible tablets (ODTs) manufacturing. Despite several excipient systems available, it is reported that the incorporation of high drug dose into the tablet mass may negatively affect both disintegration and mechanical properties. Therefore the influence of drug properties on the quality of orodispersible tablets was investigated. Fast dissolving tablet matrix was made of a co-processed excipient system F-Melt. Two grades of F-Melt that differed in composition, particle shape, and specific surface area were used to form tablet matrix. Ibuprofen, diclofenac sodium, and diltiazem hydrochloride were chosen as model drugs of different physicochemical properties such as solubility, particle size, and shape. Ninety formulations containing 12.5, 25, or 50 wt% of the model drug and F-Melt type C or M were prepared by direct compression. The quality of tablets was examined on the base of disintegration time, wetting time, mechanical resistance and texture analysis. The results showed that F-Melt grade, drug solubility, and its dose had an influence on the quality of tablets. From ninety formulations prepared, only four batches containing F-Melt type C and 12.5 wt% of ibuprofen, diclofenac sodium, or diltiazem hydrochloride could be classified as ODTs. Their disintegration time ranged from 41 to 144 s. In the case of F-Melt type M, tablets disintegrating within 101 s of friability below 1% could be prepared only if 12.5 wt% of diclofenac sodium was incorporated into the tablet mass.Key words: diclofenac sodium, diltiazem hydrochloride, direct compression, F-Melt, ibuprofen, ODTs 相似文献
107.
A relationship between people's mobility and their social networks is presented based on an analysis of calling and mobility traces for one year of anonymized call detail records of over one million mobile phone users in Portugal. We find that about 80% of places visited are within just 20 km of their nearest (geographical) social ties' locations. This figure rises to 90% at a 'geo-social radius' of 45 km. In terms of their travel scope, people are geographically closer to their weak ties than strong ties. Specifically, they are 15% more likely to be at some distance away from their weak ties than strong ties. The likelihood of being at some distance from social ties increases with the population density, and the rates of increase are higher for shorter geo-social radii. In addition, we find that area population density is indicative of geo-social radius where denser areas imply shorter radii. For example, in urban areas such as Lisbon and Porto, the geo-social radius is approximately 7 km and this increases to approximately 15 km for less densely populated areas such as Parades and Santa Maria da Feira. 相似文献
108.
109.
The molecular graphics program Sculptor and the command-line suite Situs are software packages for the integration of biophysical data across spatial resolution scales. Herein, we provide an overview of recently developed tools relevant to cryo-electron tomography (cryo-ET), with an emphasis on functionality supported by Situs 2.7.1 and Sculptor 2.1.1. We describe a work flow for automatically segmenting filaments in cryo-ET maps including denoising, local normalization, feature detection, and tracing. Tomograms of cellular actin networks exhibit both cross-linked and bundled filament densities. Such filamentous regions in cryo-ET data sets can then be segmented using a stochastic template-based search, VolTrac. The approach combines a genetic algorithm and a bidirectional expansion with a tabu search strategy to localize and characterize filamentous regions. The automated filament segmentation by VolTrac compares well to a manual one performed by expert users, and it allows an efficient and reproducible analysis of large data sets. The software is free, open source, and can be used on Linux, Macintosh or Windows computers. 相似文献
110.
The morphological and functional heterogeneity of solid tumour cells can be observed in cancer cell lines cultured in vitro. We have combined analyses of microclones developed from single cells with micropore transmigration assays to demonstrate the co-existence of cellular subsets differing in morphology and motile activity, as well as Cx43 (connexin 43) and N-cadherin expression within lung carcinoma A549 populations. 'Fibroblastoid' cells, characterized by high motility, polarized morphology and plasmalemmal localization of Cx43, displayed the strongest aptitude for transmigration through narrow obstacles. Due to high mitotic activity, they maintain the whole population but can also give rise to a sub-population of quiescent and immobile 'epithelioid' cells. Our observations indicate that phenotypic transitions between the fibroblastoid and epithelioid phenotype account for the heterogeneity of metastable A549 cell populations. 相似文献