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Mononuclear phagocytes (bone marrow monocyte-derived macrophages, alveolar macrophages, perivascular macrophages, and microglia) are reservoirs and vehicles of dissemination for the human immunodeficiency virus type-1 (HIV-1). How virus alters mononuclear phagocyte immunoregulatory activities to complete its life cycle and influence disease is incompletely understood. In attempts to better understanding the influence of virus on macrophage functions, we used one-dimensional electrophoresis, and liquid chromatography tandem mass spectrometry to analyze the secretome of HIV-1-infected human monocyte-derived macrophages. We identified 110 proteins in culture supernatants of control (uninfected) and virus-infected cells. Differentially expressed cytoskeletal, enzymes, redox, and immunoregulatory protein classes were discovered and validated by Western blot tests. These included, but were not limited to, cystatin C, cystatin B, chitinase 3-like 1 protein, cofilin-1, l-plastin, superoxide dismutase, leukotriene A(4) hydrolase, and alpha-enolase. This study, using a unique proteomics platform, provides novel insights into virus-host cell interactions that likely affect the functional role of macrophages in HIV disease.  相似文献   
84.
Introduction: The aim of the study was to evaluate some selected parameters of the antioxidative system in patients with type 2 diabetes. Materials and Methods: Eighty-one type 2 diabetes patients took part in the study (39 patients with metabolically balanced and 42 with metabolically unbalanced diabetes). The control group consisted of 30 healthy people. The total antioxidant capacity of plasma was measured fluorometrically using phycoerythrin. To calculate the low-molecular-weight antioxidant concentration in the plasma samples, the duration of Trolox activity as a function of its concentration in the sample was measured. The activity of antioxidative enzymes in red blood cells was determined using the Misra and Fridovich method and Beers and Sizer method. Results: The total plasma antioxidant capacity and the low-molecular-weight antioxidant concentration in the group of patients with metabolically compensated type 2 diabetes were statistically significantly higher than in the group of patients with metabolically uncontrolled diabetes. The activity of antioxidative enzymes was found to be higher in the group of type 2 diabetes patients at the stage of metabolic balance. Conclusions: The obtained results confirm the thesis of glucose toxicity and intensification of oxidative stress in patients with diabetes.  相似文献   
85.

Background

Catalytic subunit delta of phosphoinositide 3-kinase, p110δ, encoded by the PIK3CD gene, was recently proposed as a target for pharmacological treatment of schizophrenia. Current antipsychotic drugs were found to decrease the mRNA expression of PIK3CD, but the mechanism of this process is not known. The aim of the study was to elucidate the mechanism by which antipsychotic drugs affect the mRNA expression of PIK3CD.

Methods

The direct effect of haloperidol, clozapine, olanzapine, quetiapine and amisulpride on p110δ enzymatic activity was tested with a kinase assay, and the results were referenced against data on the mRNA expression of PIK3CD.

Results

Haloperidol, clozapine, olanzapine and quetiapine, but not amisulpride, at the concentration of 20–80?μM, were found to significantly increase enzymatic activity of p110δ by up to two times in a dose-dependent manner. Linear regression analysis revealed that more than 40% of the variance in antipsychotic drugs-induced changes in the expression of PIK3CD mRNA was explained only by changes in antipsychotic drug-regulated p110δ enzymatic activity (p?=?0.011).

Conclusions

Antipsychotic drugs differentially increase the enzymatic activity of p110δ. This effect is associated with that of mRNA expression of the PIK3CD gene. Drug-enzyme interaction may explain the effect of antipsychotic drugs on the expression of PIK3CD mRNA, however, further studies are needed to investigate this hypothesis.  相似文献   
86.
BACKGROUND: Flexible fitting of quality control procedures to method performance is an inseparable element of a cost-effective quality management strategy. However, opinions on method performance, based on a restricted number of quality control results used to calculate bias and imprecision, can vary due to the random nature of the data-gathering process. METHODS: We present an example of the bootstrap technique application in evaluating method performance estimates. RESULTS: Our analysis reveals substantial variability in method performance assessment results that should not be omitted. We suggest that the best way of using information concerning method performance is to consider the information in a probabilistic manner. Method performance is a feature presented with an element of probability. The effectiveness of a quality control procedure should be assessed with regard to this probability. CONCLUSIONS: Presented example of a bootstrap technique application increases our awareness of the uncertainty that accompanies method performance judgment and quality control planning.  相似文献   
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The gene encoding dual‐specificity tyrosine phosphorylation‐regulated kinase 1A (DYRK1A) is located within the Down syndrome (DS) critical region of chromosome 21. DYRK1A interacts with a plethora of substrates in the cytosol, cytoskeleton, and nucleus. Its overexpression is a contributing factor to the developmental alterations and age‐associated pathology observed in DS. We hypothesized that the intracellular distribution of DYRK1A and cell‐compartment‐specific functions are associated with DYRK1A posttranslational modifications. Fractionation showed that, in both human and mouse brain, almost 80% of DYRK1A was associated with the cytoskeleton, and the remaining DYRK1A was present in the cytosolic and nuclear fractions. Coimmunoprecipitation revealed that DYRK1A in the brain cytoskeleton fraction forms complexes with filamentous actin, neurofilaments, and tubulin. Two‐dimensional gel analysis of the fractions revealed DYRK1A with distinct isoelectric points: 5.5–6.5 in the nucleus, 7.2–8.2 in the cytoskeleton, and 8.7 in the cytosol. Phosphate‐affinity gel electrophoresis demonstrated several bands of DYRK1A with different mobility shifts for nuclear, cytoskeletal, and cytosolic DYRK1A, indicating modification by phosphorylation. Mass spectrometry analysis disclosed one phosphorylated site in the cytosolic DYRK1A and multiple phosphorylated residues in the cytoskeletal DYRK1A, including two not previously described. This study supports the hypothesis that intracellular distribution and compartment‐specific functions of DYRK1A may depend on its phosphorylation pattern. © 2013 Wiley Periodicals, Inc.  相似文献   
89.
The article presents the results of the analysis of the interactions between the single point incremental forming (SPIF) process parameters and the main roughness parameters of stiffened ribs fabricated in Alclad aluminium alloy panels. EN AW-7075-T6 and EN AW-2024-T3 Alclad aluminium alloy sheets were used as the research material. Panels with longitudinal ribs were produced with different values of incremental vertical step size and tool rotational speed. Alclad is formed of high-purity aluminium surface layers metallurgically bonded to aluminium alloy core material. The quality of the surface roughness and unbroken Alclad are key problems in SPIF of Alclad sheets destined for aerospace applications. The interactions between the SPIF process parameters and the main roughness parameters of the stiffened ribs were determined. The influence of forming parameters on average roughness Sa and the 10-point peak–valley surface roughness Sz was determined using artificial neural networks. The greater the value of the incremental vertical step size, the more prominent the ridges found in the inner surface of stiffened ribs, especially in the case of both Alclad aluminium alloy sheets. The predictive models of ANNs for the Sa and the Sz were characterised by performance measures with R2 values lying between 0.657 and 0.979. A different character of change in surface roughness was found for sheets covered with and not covered with a soft layer of technically pure aluminium. In the case of Alclad sheets, increasing the value of the incremental vertical step size increases the value of the surface roughness parameters Sa and Sz. In the case of the sheets not covered by Alclad, reduction of the tool rotational speed increases the Sz parameter and decreases the Sa parameter. An obvious increase in the Sz parameter was observed with an increase in the incremental vertical step size.  相似文献   
90.
As part of the experiments herein, the mechanical properties of specimens made of poly-ether-ether-ketone (PEEK) material using 3D printing technology were determined. Two populations of specimens were investigated, the first of which contained an amorphous structure, while the other held a crystal structure. The studies also investigated the influence of the print directionality on the mechanical properties obtained. Static tensile, three-point bending, and impact tests were carried out. The results for the effect of the structure type on the tensile properties showed that the modulus of elasticity was approximately 20% higher for the crystal than for the amorphous PEEK form. The Poisson’s ratios were similar, but the ratio was slightly higher for the amorphous samples than the crystalline ones. Furthermore, the studies included a chemical PEEK modification to increase the hydrophilicity. For this purpose, nitrite and hydroxyl groups were introduced into the chain by chemical reactions. The results demonstrate that the modified PEEK specimens had worse thermoplastic properties than the unmodified specimens.  相似文献   
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