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The Protein Journal - Prion diseases are a group of neurodegenerative diseases, which can progress rapidly. Previous data have demonstrated that prion protein (PrP) stimulates activation of...  相似文献   
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Aquatic Ecology - More has yet to be indicated on the ability of microphyte plants for the removal of heavy metals from contaminated environments. In the present research, the ability of the...  相似文献   
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Gastric cancer is a life-threatening disease; resulting from interaction among genetic, epigenetic, and environmental factors. Aberrant dysregulation and methylation changes in Wnt/β-catenin signaling downstream elements are a prevalent phenomenon encountered in gastric tumorigenesis. Also, viral infections play a role in gastric cancer development. CTNNBIP1 (β-catenin interacting protein 1) gene is an antagonist of Wnt signaling which binds to the β-catenin molecules. The CTNNBIP1 function as tumor suppressor gene or oncogene in different types of cancer is controversial. Moreover, its function and regulatory mechanisms in gastric cancer progression is unknown. In the present study, we examined CTNNBIP1 gene expression, the methylation status of the regulatory region of the gene, and their association with Epstein–Barr virus (EBV), and cytomegalovirus (CMV) and Helicobacter pylori infections in human gastric adenocarcinoma tissues in comparison with their adjacent nontumoral tissues. Our data revealed a significant downregulation of CTNNBIP1 in gastric tumors. Female patients showed lower level of CTNNBIP1 than males (p < 0.05). Also, decreased expression of CTNNBIP1 was markedly associated with well-differentiated tumor grades (p < 0.05). No methylation change was observed between tumoral and nontumoral tissues. Additionally, CTNNBIP1 down regulation was significantly associated with CMV infection (p < 0.05). In the absence of EBV infection, lower expression of CTNNBIP1 was observed. There was no association between H. pylori infection and CTNNBIP1 expression. Our findings revealed the tumor suppressor role for CTNNBIP1 in gastric adenocarcinoma. Interestingly, EBV and CMV infections modulate CTNNBIP1 expression.  相似文献   
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Prostate cancer (PCa) is considered the most prevalent malignancy and the second major cause of cancer-related death in males from Western countries. PCa exhibits variable clinical pictures, ranging from dormant to highly metastatic cancer. PCa suffers from poor prognosis and diagnosis markers, and novel biomarkers are required to define disease stages and to design appropriate therapeutic approach by considering the possible genomic and epigenomic differences. MicroRNAs (miRNAs) comprise a class of small noncoding RNAs, which have remarkable functions in cell formation, differentiation, and cancer development and contribute in these processes through controlling the expressions of protein-coding genes by repressing translation or breaking down the messenger RNA in a sequence-specific method. miRNAs in cancer are able to reflect informative data about the current status of disease and this might benefit PCa prognosis and diagnosis since that is concerned to PCa patients and we intend to highlight it in this paper.  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - Artemisinin is an efficient anti-malarial drug and it possesses biological activity against a wide range of cancers. The combined application of two...  相似文献   
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ObjectivesPeri-implantitis is a destructive inflammatory process that affects the soft and hard tissues around dental implants. porphyromonas gingivalis, an anaerobic gram-negative bacterium, appears to be the main culprit. Since there is no efficient and specific vaccine to treat peri-implantitis, the goal of our research has been to develop a multi-epitope vaccination utilizing an immunoinformatics approach that targeted P. gingivalis type I fim A.Materials and methodsP. gingivalis peptides 6JKZ and 6KMF are suitable for vaccine development. B- and T-cell epitopes from 6KMF and 6JKZ were detected and evaluated based on critical factors to produce a multi-epitope vaccine construct. It was assessed based on allergenicity, antigenicity, stability. The vaccine's dual major histocompatibility complex (MHC-I and MHC-II) binding epitopes allowed it to reach a larger population. P. gingivalis fimbriae induce immune subversion through TLR -CXCR4 receptor complex pathway. The ClusPro 2.0 server was used to do the molecular docking using TLR2 - CXCR4 and vaccine epitopes as receptor and ligand respectively.ResultsThe designed vaccine was non-allergenic and had a high antigenicity, solubility, and stability. The 3D structure of the vaccine revealed strong interaction with CXCR4(TLR2) using molecular docking. The vaccine-CXCR4 interface was more consistent, possibly because the vaccination has a higher affinity for the CXCR4-TLR2 complex.ConclusionThis study details the vaccine's distinct and sustained interaction with the CXCR4(TLR2) immunological receptor and its consistent and effective utterance in the bacterial system. As a result, our vaccine formulation will evoke a significant memory response and induce an adaptive immune response against P. gingivalis.  相似文献   
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Geometries and energies of formation of bilirubin formed by reduction of biliverdin via three meso carbon sites, the , and positions, have been calculated using semiempirical methods. It has been shown that -bilirubin with a ridge-tile conformation forms six intramolecular hydrogen bonds and is the most stable of the three above mentioned positions by at least 22 kcal mol–1. Reduction pathways for -, - and -bilirubin formations from biliverdin are studied in detail. The roles of loss of conjugation and hydrogen bond formations in stability of different conformers have been discussed. -Bilirubin was fully optimized by using ab initio methods. Fine refinements of calculated results show excellent agreement with experimental results. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00894-002-0078-9.Electronic Supplementary Material available.  相似文献   
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The focus of both clinical and basic studies on stem cells is increasing due to their potentials in regenerative medicine and cell-based therapies. Recently stem cells have been genetically modified to enhance an existing character in or to bring a new property to them. However, accomplishment of declared goals requires detailed knowledge about their molecular characteristics which could be achieved by genetic modifications mostly through nonviral transfection strategies. Capable of differentiating into multiple cells, human unrestricted somatic stem cells (hUSSCs) and human mesenchymal stem cells (hMSCs) seem to be suitable candidates for transfection approaches. Involvement of microRNAs (miRNAs) in many biological processes makes their transfection evaluation valuable. Herein we investigated the efficacy and toxicity of four typically used transfection reagents (Arrest-In, Lipofectamine 2000, Oligofectamine and HiPerfect) systematically to deliver fluorescent labeled-miRNA and Green Fluorescent Protein (GFP) expressing plasmid into hUSSCs and hMSCs. The authenticity of stem cells was verified by differentiation experiments along with flow cytometry of surface markers. Our study revealed that stemness properties of these stem cells were not affected by transient transfection. Moreover the ratios of cell viability and transfection efficiency in both analyzed stem cells were reversed. Considering cell viability, the highest fraction of GFP-expressing cells was obtained using Oligofectamine (~50%) while the highest transfection rate of miRNA was achieved by Lipofectamine 2000 (~90%). Moreover dependency of hMSCs to size of transfected nucleic acid and time-dependency of Oligofectamine and their affection on the yield of transfection were observed. Cytotoxicity assessments also showed that hUSSCs are sensitive to HiPerFect. In addition cells treated by Lipofectamine showed morphological changes. Representing the efficient nucleic acid transfection, our research facilitates comprehensive genetic modification of stem cells and demonstrates powerful approaches to understand stem cell molecular regulation mechanisms, which eventually improves nonviral cell-mediated gene therapy.

Electronic supplementary material

The online version of this article (doi:10.1007/s10616-012-9430-9) contains supplementary material, which is available to authorized users.  相似文献   
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