51 research outputs found
Attenuation of serum laminin concentrations upon treatment of chronic hepatitis
Objectives: The aim of this work was to determine the serum laminin level cutoff point for predicting liver fibrosis highlighting its diagnostic value and determining the effect of treatment on serum laminin concentrations. Methods: Serum laminin concentrations in chronic hepatitis patients (n=62) and controls (n=20) were compared by ELISA and stages of fibrosis were assessed according to the modified Knodell score system. Results: Mean serum laminin concentration in patients (91.9 ± 20.9 ng/ml) was greater than controls (46.2 ± 10.2 ng/ml; p <0.001). Serum concentrations of laminin in all stages of hepatic fibrosis were significantly higher than those of healthy controls (p <0.05). A cutoff point of 52ng laminin/ml of serum was obtained for the discrimination of various stages of liver fibrosis showing a good sensitivity (96.8%) and specificity (80%). After 6 months of treatment, a gradual decrease in serum laminin concentrations were observed, however the level was still higher than that of the healthy group (p<0.05). Conclusions: Our findings suggest that the serum laminin concentration is a useful noninvasive marker of liver fibrosis and shows a strong positive correlation with different stages of the disease
Influence of zinc incorporation on microstructure of hydroxyapatite to characterize the effect of pH and calcination temperatures
AbstractThis work was focused to study the existence of Zn2+ in structure, chemical composition as well as particle and crystallite size of hydroxyapatite (HAp) to characterize the effect of pH of the solution and calcination temperature. Non-stoichiometric HAp (nHAp) powders containing 4at.% zinc fraction were synthesized via solution–precipitation method. In order to characterize the effect of pH (values: 9 and 10.5) and two calcination temperatures (550 and 1000°C) on chemical composition, molecule internal bonds, particle and crystallite size of the synthesized powders, XRD, EDS, FTIR and SEM techniques were utilized. The results showed that zinc cations could be incorporated in the HAp atomic structure to form low crystalline single phase of nHAP. The pH adjustment to 10.5 caused the formation of powders with smaller particle and crystallite sizes. The results also indicated that calcination temperature up to 1000°C caused decomposition of zinc doped nHAp to β-tri calcium phosphate and tri zinc calcium phosphate phases which are used to control the speed of biodegradation
Tubular cell phenotype in HIV-associated nephropathy: Role of phospholipid lysophosphatidic acid
Collapsing glomerulopathy and microcysts are characteristic histological features of HIV-associated nephropathy (HIVAN). We have previously reported the role of epithelial mesenchymal transition (EMT) in the development of glomerular and tubular cell phenotypes in HIVAN. Since persistent tubular cell activation of NF kappa B has been reported in HIVAN, we now hypothesize that HIV may be contributing to tubular cell phenotype via lysophosphatidic acid (LPA) mediated downstream signaling. Interestingly, LPA and its receptors have also been implicated in the tubular interstitial cell fibrosis (TIF) and cyst formation in autosomal dominant polycystic kidney disease (PKD). Primary human proximal tubular cells (HRPTCs) were transduced with either empty vector (EV/HRPTCs), HIV (HIV/HRPTCs) or treated with LPA (LPA/HRPTC). Immunoelectrophoresis of HIV/HRPTCs and LPA/HRPTCs displayed enhanced expression of pro-fibrotic markers: a) fibronectin (2.25 fold), b) connective tissue growth factor (CTGF; 4.8 fold), c) alpha-smooth muscle actin (alpha-SMA; 12 fold), and d) collagen 1(5.7 fold). HIV enhanced tubular cell phosphorylation of ILK-1, FAK, PI3K, Akt, ERKs and P38 MAPK HIV increased tubular cell transcriptional binding activity of NF-kappa B; whereas, a LPA biosynthesis inhibitor (AACOCF3), a DAG kinase inhibitor, a LPA receptor blocker (Ki16425), a NF-kappa B inhibitor (PDTC) and NF kappa B-siRNA not only displayed downregulation of a NF kappa B activity but also showed attenuated expression of profibrotic/EMT genes in HIV milieu. These findings suggest that LPA could be contributing to HIV-induced tubular cell phenotype via NF kappa B activation in HIVAN. (C) 2015 Elsevier Inc. All rights reserved
Docosahexaenoic acid sensitizes Ramos cells to Gamma-irradiation-induced apoptosis through involvement of PPAR-γ activation and NF-κB suppression
Gamma-irradiation (Gamma-IR) resistance is a character of many malignant cells that decreases the efficacy of radiotherapy. Although ionizing radiation activates multiple cellular factors that vary depending on dose and tissue specificity, the activation of nuclear factor-κB appears to be a well-conserved response in tumor cells exposed to Gamma-IR which can lead to the inhibition of radiation-induced apoptosis. Thus, inhibition of NF-kappa;B activation is an important strategy to abolish radioresistance. Recently, we have demonstrated that docosahexaenoic acid (DHA; 22:6 n-3 polyunsaturated fatty acids)-induced apoptosis may occur via ligand-dependent transcription factor, peroxisome proliferator-activated receptors-gamma. Moreover, many reports described that activation of PPAR-γ can lead to the induction of apoptosis through NF-κB inhibition. Therefore, we addressed the mechanism that NF-κB is a downstream target of DHA and may be involved in the process of radiosensitization. Ramos cells are a highly radiation-resistant and p53-deficient Burkitt's lymphoma cell line. The results of present study showed that cotreatment of Ramos cells with low doses of DHA and Gamma-IR leads to marked phosphorylation of κB and translocation of p65/NF-κB to nucleus in parallel with increase in apoptosis. Preincubation of the cells with GW9662, a selective antagonist for PPAR-γ, significantly prevented NF-κB activation profile. Taken together, these results suggest that low concentration of DHA inhibited Gamma-IR-induced activation of NF-κB and sensitized Ramos cells to IR-induced cytotoxicity. Pretreatment of Ramos cells with GW9662 abrogated the ability of DHA to inhibit Gamma-IR-induced activation of NF-κB and diminished the DHA radiosensitizing effect indicating that PPAR-γ may act as a mediator of DHA in inhibition of NF-κB. Taken together, these results suggest that low concentration of DHA inhibited Gamma-IR-induced activation of NF-κB and sensitized Ramos cells to IR-induced cytotoxicity. Pretreatment of Ramos cells with GW9662 abrogated the ability of DHA to inhibit Gamma-IR-induced activation of NF-κB and diminished the DHA radiosensitizing effect indicating that PPAR-γ may act as a mediator of DHA in inhibition of NF-κB. © Springer Science+Business Media, LLC. 2008
Large scale and low cost synthesis of multiwalled carbon nanotubes by mechanothermal absence catalysts
Multiwalled carbon nanotubes (MWCNTs) were obtained by mechanothermal activation under argon atmosphere and subsequent annealing. The chemical activity and crystallinity grade of carbon atoms were studied at different milling times and annealing temperatures. The synthesised MWCNTs were characterised by X-ray diffraction, and their morphologies were observed by means of scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). Efficiency examination was measured using thermogravimetric analysis (TGA) after heat treatment. In addition, the crystal structures were analysed in terms of their bright field images and selected area electron diffraction (SAED) pattern of high resolution transmission electron microscopy (HRTEM). The mechanothermal method is of interest for fundamental understanding and for improvement of commercial synthesis of carbon nanotubes (CNTs). In fact, the mechanothermal method guarantees the production of CNTs for different applications especially reinforcement materials in ceramic matrix composites (CMCs)
Effect of deflocculant on microsilica containing ultra low cement Al2O3-SiC refractory castable
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Exploring the binding mechanism of saccharin and sodium saccharin to promoter of human p53 gene by theoretical and experimental methods
Serum hyaluronic acid and laminin as biomarkers in liver fibrosis
Background and Aim: Non-invasive methods have been proposed as surrogate markers for liver biopsy. It was shown that serum hyaluronic acid (HA) and laminin (LN) levels increase with the development of liver fibrosis. The aim of this study was to determine serum HA and LN levels cut-off points for predicting liver fibrosis, highlighting their diagnostic value and their changes during treatment. Methods: Serum HA and LN levels in chronic hepatitis patients (n=62) and controls (n=20) were assessed by ELISA and liver histopathological parameters were evaluated by the modified Knodell score. Results: Mean serum HA (113.4±59.2 ng/ml) and LN (91.9±20.9 ng/ml) concentrations in patients were greater than in controls (46.6±10.5 and 46.1±10.1 ng/ml, p<0.001). A strong correlation between serum HA and LN concentrations with hepatic necroinflammatory lesions was found (p<0.001). A cut-off point of 59.5 ng/ml HA and 52.0 ng/ml LN for the discrimination of patients with liver fibrosis from healthy controls and 102.0 ng/ml HA and 92.5 ng/ml LN for the discrimination of patients with mild from severe fibrosis showed acceptable AUC, sensitivity and specificity. After six months of treatment, a gradual decrease in serum HA and LN levels was observed, however the levels were still higher than those of the controls (p<0.05). Conclusions: Serum hyaluronic acid and laminin concentrations increase in liver fibrosis and could be used as a noninvasive biomarker to discriminate between patients with liver fibrosis and healthy individuals
Clinical significance of long noncoding RNA VIM-AS1 and CTBP1-AS2 expression in type 2 diabetes
Background/Aims: The risk of type 2 diabetes (T2D) is determined by a combination of genetic and environmental factors. Multiple studies have proposed that long noncoding RNAs (lncRNAs) are crucial molecules in regulating several biological processes and complex diseases. The study was aimed at investigating the association between the expression levels of lncRNA VIM-AS1, lncRNA CTBP1-AS2, and T2D susceptibility. Methods: lncRNA VIM-AS1 and lncRNA CTBP1-AS2 in the peripheral blood mononuclear cell (PBMC) of 100 healthy individuals and 100 T2D patients were collected for Quantitative Real-Time RT-PCR analysis. A logistic regression was performed to understand whether the likelihood of T2D can be predicted based on the expression levels of lncRNA VIM-AS1 and lncRNA CTBP1-AS2. Receiver operating characteristic (ROC) analysis was also performed to determine the statistical analysis of VIM-AS1 and CTBP1-AS2 levels in 200 samples. Results: Our results display that decreased levels of VIM-AS1 and CTBP1-AS2 in PBMC were associated with diabetes in Iranian population. The logistic regression revealed that Systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), Fasting blood glucose (FBG) and CTBP1-AS2 are substantial predictors of T2D. The ROC analysis of CTBP1-AS2 revealed the area under the ROC curve (AUC) of 0.68 with a sensitivity of 58.7 and specificity of 75.3 in distinguishing nondiabetic from diabetic subjects. The ROC analysis of VIM-AS1 determined AUC of 0.63 with a sensitivity of 56.1 and specificity of 68.37 in distinguishing the two diagnostic groups. Conclusion: lncRNA VIM-AS1 and lncRNA CTBP1-AS2 expression levels are associated with T2D susceptibility. © 2018 Wiley Periodicals, Inc
Protein adsorption on electrospun zinc doped hydroxyapatite containing nylon 6 membrane: Kinetics and isotherm
10.1016/j.jcis.2014.12.014Journal of Colloid and Interface Science443143-15
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