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1.
Mnemiopsin 1 (Mn1) and Mnemiopsin 2 (Mn2) are photoproteins found in Mnemiopsis leidyi. We have tried to answer the question of whether the structural features of photoproteins can explain the observed activity data. According to the activity measurements data, they have the same characteristic wavelength. However, the initial intensity of Mn2 is significantly higher than that of Mn1, and decay time of Mn1 (0.92 s−1) is lower than that of Mn2 (1.46 s−1). The phylogenetic analysis demonstrates that, compared with Obelin and Aequorin from Obelia longissima and Aequorea victoria, respectively, a gene modification event may have caused the expansion of the N-terminal side of all photoproteins from M. leidyi. An in silico study has shown that the stability of the photoprotein–substrate complex of Mn2 is higher than that of Mn1, indicating a higher affinity of the substrate for Mn2 compared with Mn1. It was revealed that the active EF-hand loops 1 and III in Mn2 is locally more rigid compared with those in Mn1. We concluded that different stability of the photoprotein complexes leads to different initial intensity. While different patterns of the local dynamics of loops I and III may influence the decay rate.  相似文献   
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Accumulating evidence has indicated that deregulation of lncRNAs plays essential roles in colorectal cancer (CRC) carcinogenesis. The goal of this study was to analyze the expression of lncRNAs in colorectal cancer and their association with clinicopathological variables. Bioinformatics analysis of published CRC microarray data was performed to identify the important lncRNAs. The expression levels of candidate genes were assessed in the human colon cancer/normal cell lines, CRC, adenomatous colorectal polyps, and their marginal tissues by qRT-PCR. Moreover, the methylation status of the TRPM2-AS1 promoter was studied using qMSP assay. Furthermore, we investigated the molecular mechanisms of these lncRNAs in CRC progression using in silico analysis. Microarray analysis revealed that lncRNAs SNHG6, MIR4435-2HG, and TRPM2-AS1 were upregulated in CRC. These results were validated in colon cell lines. Moreover, qRT-PCR showed that the expression levels of SNHG6 and TRPM2-AS1 were upregulated in the colorectal tumor tissues compared with their paired tissues. Nonetheless, there was no significant increase in MIR4435-2HG expression in CRC samples. Furthermore, we observed a significant hypomethylation of TRPM2-AS1 promoter and its activation in CRC tissues. By in silico analysis, we found that the lncRNAs upregulation could promote proliferation and drug resistance of colorectal cancer cells via miRNAs sponging and modulation of their targets expression. In conclusion, based on our results upregulation of SNHG6 and TRPM2-AS1, and hypomethylation of TRPM2-AS1 promoter might be considered as potential diagnostic biomarkers for CRC initiation and development.  相似文献   
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Antimicrobial peptide Temporin-Ra was isolated from the skin secretions of marsh frog Rana ridibunda. Temporin-Ra was chemically synthesized and purified using RP-HPLC technique. The cytotoxicity of peptide on lung airway epithelial cell line (A549) and peripheral blood mononuclear cells (PBMC) was studied by MTT assay. Furthermore, the effect of Temporin-Ra on the expression of pro-inflammatory factors such as IL-1β and IL-8 in A549 cell line was evaluated at peptide concentrations of 15, 30 and 50 μg/mL for 6, 12 and 24 h using semi-quantitative RT-PCR and real-time PCR methods. The result of our experiments revealed that Temporin-Ra decreased cell viability about 3–13 % in A549 cells and 4–6 % in PBMC cells. Moreover, Temporin-Ra induced the mRNA expression of IL-1β and IL-8 genes in a dose- and time-dependent manner. According to our results, maximum IL-8 mRNA expression was observed after a 24-h treatment of cancer cells with 50 μg/mL peptide with approximately 18-fold increase in expression. The least expression level of IL-1β was observed after 6-h of incubation in the presence of 15 μg/mL peptide with 2.5-fold increase in expression whereas the most expression level was obtained following 24 h-treatment with 50 μg/mL peptide with 26-fold increase in mRNA expression. Eventually, the present study highlights the role of Temporin-Ra as a potent antimicrobial peptide in the activation and maintenance of inflammatory processes.  相似文献   
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Rapid growth in nanotechnology toward the development of nanomedicine agents holds massive promise to improve therapeutic approaches against cancer. Nanomedicine products represent an opportunity to achieve sophisticated targeting strategies and multifunctionality. Nowadays, nanoparticles (NPs) have multiple applications in different branches of science. In recent years, NPs have repetitively been reported to play a significant role in modern medicine. They have been analyzed for different clinical applications, such as drug carriers, gene delivery to tumors, and contrast agents in imaging. A wide range of nanomaterials based on organic, inorganic, lipid, or glycan compounds, as well as on synthetic polymers has been utilized for the development and improvement of new cancer therapeutics. In this study, we discuss the role of NPs in treating cancer among different drug delivery methods for cancer therapy.  相似文献   
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Retinopathy of prematurity (ROP) is a multifactorial disease, that cause visual impairment in premature children. The exact pathogenesis and etiology of ROP is unknown and genetic susceptibility is considered as risk factor. Vascular endothelial growth factor (VEGF) plays a major role in retinal neovascularization and subsequently retinal detachment. VEGF polymorphism is associated with proliferative ROP in some studies. We examined the possible association of the VEGF gene polymorphisms with ROP in preterm infants in south of Iran. A total of 111 preterm infants were examined by ophthalmologist and after that were genotyped. Genotyping of the VEGF +405 (rs2010963) and VEGF +936 (rs3025039) was done by the polymerase chain reaction and restriction fragment length polymorphism methods. The frequency of VEGF alleles, genotypes and haplotype distribution were compared between groups. The patients were divided in three groups: 66 to the normal group (normal fundoscopy), and 45 to the ROP group; 30 infants were not treated with Lasertherapy (Regressive group) and 15 treated with Lasertherapy. The frequency of VEGF +405 and VEGF +936 G/C genotypes as well as allele frequencies was not different between groups. No significant difference was found between ROP with treatment and ROP without lasertherapy. Our report indicate that there is no association between the carrier states of gene polymorphisms VEGF +405, VEGF +936 and progression or spontaneous regression of ROP in preterm infants in Iranian population. However, it should be considered that angiogenesis is a complex process and genetic factors in addition to environmental factors are contributed in this pathway.  相似文献   
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IntroductionImmune checkpoint inhibition has shifted treatment paradigms in non-small cell lung cancer (NSCLC). Conflicting results have been reported regarding the immune infiltrate and programmed death-ligand 1 (PD-L1) as a prognostic marker. We correlated the immune infiltrate and PD-L1 expression with clinicopathologic characteristics in a cohort of resected NSCLC.MethodsA tissue microarray was constructed using triplicate cores from consecutive resected NSCLC. Immunohistochemistry was performed for CD8, FOXP3 and PD-L1. Strong PD-L1 expression was predefined as greater than 50% tumor cell positivity. Matched nodal samples were assessed for concordance of PD-L1 expression.ResultsOf 522 patients, 346 were node-negative (N0), 72 N1 and 109 N2; 265 were adenocarcinomas (AC), 182 squamous cell cancers (SCC) and 75 other. Strong PD-L1 expression was found in 24% cases. In the overall cohort, PD-L1 expression was not associated with survival. In patients with N2 disease, strong PD-L1 expression was associated with significantly improved disease-free (DFS) and overall survival (OS) in multivariate analysis (HR 0.49, 95%CI 0.36–0.94, p = 0.031; HR 0.46, 95%CI 0.26–0.80, p = 0.006). In this resected cohort only 5% harboured EGFR mutations, whereas 19% harboured KRAS and 23% other. KRAS mutated tumors were more likely to highly express PD-L1 compared to EGFR (22% vs 3%). A stromal CD8 infiltrate was associated with significantly improved DFS in SCC (HR 0.70, 95%CI 0.50–0.97, p = 0.034), but not AC, whereas FOXP3 was not prognostic. Matched nodal specimens (N = 53) were highly concordant for PD-L1 expression (89%).ConclusionPD-L1 expression was not prognostic in the overall cohort. PD-L1 expression in primary tumor and matched nodal specimens were highly concordant. The observed survival benefit in N2 disease requires confirmation.  相似文献   
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A new series of coumarin‐3‐carboxamide‐N‐morpholine hybrids 5a – 5l was designed and synthesized as cholinesterases inhibitors. The synthetic approach for title compounds was started from the reaction between 2‐hydroxybenzaldehyde derivatives and Meldrum's acid to afford corresponding coumarin‐3‐carboxylic acids. Then, amidation of the latter compounds with 2‐morpholinoethylamine or N‐(3‐aminopropyl)morpholine led to the formation of the compounds 5a – 5l . The in vitro inhibition screen against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) revealed that most of the synthesized compounds had potent AChE inhibitory while their BuChE inhibitions are moderate to weak. Among them, propylmorpholine derivative 5g (N‐[3‐(morpholin‐4‐yl)propyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing an unsubstituted coumarin moiety and ethylmorpholine derivative 5d (6‐bromo‐N‐[2‐(morpholin‐4‐yl)ethyl]‐2‐oxo‐2H‐chromene‐3‐carboxamide) bearing a 6‐bromocoumarin moiety showed the most activity against AChE and BuChE, respectively. The inhibitory activity of compound 5g against AChE was 1.78 times more than that of rivastigmine and anti‐BuChE activity of compound 5d is approximately same as rivastigmine. Kinetic and docking studies confirmed the dual binding site ability of compound 5g to inhibit AChE.  相似文献   
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Conversion of CO2 to energy‐rich chemicals using renewable energy is of much interest to close the anthropogenic carbon cycle. However, the current photoelectrochemical systems are still far from being practically feasible. Here the successful demonstration of a continuous, energy efficient, and scalable solar‐driven CO2 reduction process based on earth‐abundant molybdenum disulfide (MoS2) catalyst, which works in synergy with an inexpensive hybrid electrolyte of choline chloride (a common food additive for livestock) and potassium hydroxide (KOH) is reported. The CO2 saturated hybrid electrolyte utilized in this study also acts as a buffer solution (pH ≈ 7.6) to adjust pH during the reactions. This study reveals that this system can efficiently convert CO2 to CO with solar‐to‐fuel and catalytic conversion efficiencies of 23% and 83%, respectively. Using density functional theory calculations, a new reaction mechanism in which the water molecules near the MoS2 cathode act as proton donors to facilitate the CO2 reduction process by MoS2 catalyst is proposed. This demonstration of a continuous, cost‐effective, and energy efficient solar driven CO2 conversion process is a key step toward the industrialization of this technology.  相似文献   
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