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1.
Prostate cancer (PCa) is one of the most epidemic types of cancer in men. The tumor microenvironment (TME) of PCa is involved in the emergence of immunosuppressive factors such as myeloid-derived suppressor cells (MDSC), which regulate the immune system by several mechanisms, including interleukin (IL)-10 production. On the other hand, IL-17+ helper T cells (Th17) induce MDSCs and chronic inflammation in TME by producing IL-17. This study demonstrated that the frequency of CD33+ pSTAT3+ MDSC and IL-17+ lymphocyte as well as IL-10 messenger RNA (mRNA) expression were significantly higher in the PCa patients than in the benign prostatic hyperplasia (BPH) group. Moreover, there was no significant relationship between the frequency of CD33+ pSTAT3+ MDSC, and IL-17+ lymphocyte with Gleason scores in the PCa group. We suggested that the higher frequency of CD33+ pSTAT3+ MDSC and IL-17+ lymphocyte and the more frequent expression of IL-10 mRNA in PCa patients may play roles in tumor progression from BPH to PCa.  相似文献   
2.
This paper describes the interaction between 2,4-dinitrophenol (DNP) with the two drug carrier proteins – human serum albumin (HSA) and human holo transferrin (HTF). Hence, binding characteristics of DNP to HSA and HTF were analyzed by spectroscopic and molecular modeling techniques. Based on results obtained from fluorescence spectroscopy, DNP had a strong ability to quench the intrinsic fluorescence of HSA and HTF through a static quenching procedure. The binding constant and the number of binding sites were calculated as 2.3?×?1011?M?1 and .98 for HSA, and 1.7?×?1011?M?1 and 1.06 for HTF, respectively. In addition, synchronous fluorescence results showed that the microenvironment of Trp had a slight tendency of increasing its hydrophobicity, whereas the microenvironment of the Tyr residues of HSA did not change and that of HTF showed a significant trend (red shift of about 4?nm) of an increase in polarity. The distance between donor and acceptor was obtained by the Förster energy according to fluorescence resonance energy transfer, and was found to be 3.99 and 3.72?nm for HSA and HTF, respectively. The critical induced aggregation concentration (CCIAC) of the drug on both proteins was determined and confirmed by an inflection point of the zeta potential behavior. Circular dichroism data revealed that the presence of DNP caused a decrease of the α-helical content of HSA and HTF, and induced a remarkable mild denaturation of both proteins. The molecular modeling data confirmed our experimental results. This study is deemed useful for determining drug dosage.  相似文献   
3.
"Candidatus Phytoplasma aurantifolia" is the causative agent of witches' broom disease in the Mexican lime tree (Citrus aurantifolia L.), and is responsible for major tree losses in Southern Iran and Oman. The pathogen is strictly biotrophic, and, therefore, completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We applied a proteomics approach to analyse gene expression in Mexican limes infected with "Ca. Phytoplasma aurantifolia". Leaf samples were collected from healthy and infected plants and were analysed using 2-DE coupled with MS. Among 800 leaf proteins that were detected reproducibly in eight biological replicates of healthy and eight biological replicates of infected plants, 55 showed a significant response to the disease. MS resulted in identification of 39 regulated proteins, which included proteins that were involved in oxidative stress defence, photosynthesis, metabolism, and the stress response. Our results provide the first proteomic view of the molecular basis of the infection process and identify genes that could help inhibit the effects of the pathogen.  相似文献   
4.
Adipose-derived stem cells (ASCs) are regarded as a major player of breast cancer microenvironment. By production of various growth factors and expression of regulatory molecules, it is postulated that ASCs protect breast cancer cells from the host immune responses. In this study, the expressions of insulin-like growth factor-1 (IGF-1), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), CXCL8 (IL-8) in breast cancer cells and adipose-derived stem cells isolated from breast tissue of women with breast cancer were investigated. The results were analyzed comparatively in normal ASCs isolated from healthy normal women. In case of breast cancer tissues, results were analyzed between high stage and low stage patients. The expressions of extracted mRNAs were determined using real-time quantitative RT-PCR. As a result, in breast cancer tissues, IGF-1 and IL-8 mRNAs had 28.6 and 56-fold more expressions in high stage compared to low stage patients. In ASCs, relative quantifications (RQ) of VEGF, IL-8, HGF and IGF-1 was about 2-fold higher in patients than controls. Data of this study conclude that presence of resident ASCs within the scaffold of breast tissue may support breast tumor growth and progression through the expressions of tumor promoting factors.  相似文献   
5.
Iranian borage (Echium amoenum) from Boraginaceae is a valuable medicinal plant native to Iran and Syria. We determined fatty acid profile and individual fatty acid contents in E. amoenum seed oil using gas chromatography. Nevertheless, the cumulative amount of ω-6 and ω-3 fatty acids in E. amoenum (78.5 %) was in great accordance with those of other species of Echium, Stearidonic acid (SDA, C18:4ω3) and gamma-linolenic acid (GLA, C18:3ω6) constituted only 9.7 % of seed oil in this plant. This observation elucidated the weak activity of delta-6 desaturase (D6DES) in E. amoenum compared with D6DESs of other species. As D6DES enzyme is responsible for converting linoleic acid (LA, C18:2ω6) and alpha-linolenic acid (ALA, C18:3ω3) to GLA and SDA, we isolated coding sequence of D6DES gene and characterized primary structure of the translated protein to probably find some evidences explaining the weak activity of D6DES enzyme in E. amoenum. Gene sequence from E. amoenum showed a high identity of 94–96 % with the other Echium species and the amino acid homology increased by 98 %. All the expected signatures including cytochrome b5 domain and three conserved histidine-rich motifs were found in the translated amino acid sequence. Protein alignment revealed that all the conserved motifs in D6DES sequence from E. amoenum are coincident with its counterparts from other Echium species. However, secondary structure of the enzyme deduced from its primary structure using computational simulation represented obvious differences with D6DES proteins of the other species.  相似文献   
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7.
Correction to A. Louren?o, M. Conover, A. Wong, A. Nematzadeh, F. Pan, H. Shatkay, and L.M. Rocha."A Linear Classifier Based on Entity Recognition Tools and a Statistical Approach to Method Extraction in the Protein-Protein Interaction Literature". BMC Bioinformatics 2011, 12(Suppl 8):S12. doi:http://10.1186/1471-2105-12-S8-S12.  相似文献   
8.
CRC-associated P53 mutations have not been studied extensively in non-Western countries at relatively low CRC risk. We examined, for the first time, 196 paraffin-embedded CRC cases from Northern Iran for mutations in P53 exons 5-8 using PCR-direct sequencing. P53 status and mutation site/type were correlated with nuclear protein accumulation, clinicopathologic variables and data on K-ras mutations and high-level microsatellite instability (MSI-H). We detected 96 P53 mutations in 87 (44.4%) cases and protein accumulation in 84 cases (42.8%). P53 mutations correlated directly with stage and inversely with MSI-H. Distal CRCs were more frequently mutated at major CpG hotspot codons [248 (8/66, 12.1%), 175 (7/66, 10.6%), and 245 (7/66, 10.6%)], while in proximal tumors codon 213, emerged as most frequently mutated (5/28, 17.9% vs. 3/66, 4.5%, P = 0.048). Transitions at CpGs, the most common mutation type, were more frequent in non-mucinous (25% vs. 10.4% in mucinous, P = 0.032), and distal CRC (27% vs. 12.5% in proximal, P = 0.02), and correlated with K-ras transversions. Transitions at non-CpGs, second most common P53 mutation, were more frequent in proximal tumors (15.6% vs. 4.7% in distal, P = 0.01), and correlated with K-ras transitions and MSI-H. Overall frequency and types of mutations and correlations with P53 accumulation, stage and MSI-H were as reported for non-Iranian patients. However P53 mutation site/type and correlations between P53 and K-ras mutation types differed between proximal and distal CRC. The codon 213 P53 mutation that recurred in proximal CRC was previously reported as frequent in esophageal cancer from Northern Iran.  相似文献   
9.
The role of the antioxidant defense system in salt tolerance of Aeluropus littoralis has not been yet reported; therefore in the present study, the changes of catalase (CAT) activity in this halophyte plant was investigated and CAT gene was isolated. The leaves of treated and control plants were harvested at various times, starting 1 day prior to initiating treatment, then periodically at 72-h intervals for 21 days. The data collected showed that CAT activity increased significantly with time in plants treated with 200, 400, and 600 mM NaCl when compared with the control plants. Maximum enzyme activity was observed between the 6th and 12th day at all NaCl concentrations. CAT gene was isolated and cloned via pTZ57R/T cloning vector in Escherichia coli. CAT gene encoded 494 amino acids and had also high homology of 90, 87, 86, and 86% with CAT genes from Zea mays, Oryza sativa, Triticum aestivum, and Hordeum vulgare, respectively.  相似文献   
10.
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