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A simple, clean and environmentally benign route to the synthesis of 2-amino-4H-chromenes is described using Preyssler type heteropolyacid, H(14)[NaP(5)W(30)O(110)], as a green and reusable catalyst in water. The products were obtained in very good yields.  相似文献   
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Epiblast stem cells (EpiSCs), which are pluripotent cells isolated from early post-implantation mouse embryos (E5.5), show both similarities and differences compared to mouse embryonic stem cells (mESCs), isolated earlier from the inner cell mass (ICM) of the E3.5 embryo. Previously, we have observed that while chromatin is very dispersed in E3.5 ICM, compact chromatin domains and chromocentres appear in E5.5 epiblasts after embryo implantation. Given that the observed chromatin re-organization in E5.5 epiblasts coincides with an increase in DNA methylation, in this study, we aimed to examine the role of DNA methylation in chromatin re-organization during the in vitro conversion of ESCs to EpiSCs. The requirement for DNA methylation was determined by converting both wild-type and DNA methylation-deficient ESCs to EpiSCs, followed by structural analysis with electron spectroscopic imaging (ESI). We show that the chromatin re-organization which occurs in vivo can be re-capitulated in vitro during the ESC to EpiSC conversion. Indeed, after 7 days in EpiSC media, compact chromatin domains begin to appear throughout the nuclear volume, creating a chromatin organization similar to E5 epiblasts and embryo-derived EpiSCs. Our data demonstrate that DNA methylation is dispensable for this global chromatin re-organization but required for the compaction of pericentromeric chromatin into chromocentres.  相似文献   
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Melanoma is the most serious type of skin cancer which develops from the occurrence of genetic mutations in the melanocytes. Based on the features of melanoma tumors such as location, genetic profile and stage, there are several therapeutic strategies including surgery, chemotherapy, and radiotherapy. However, because of the appearance resistance mechanisms, the efficiency of these treatments strategies may be reduced. It has been demonstrated that therapeutic monoclonal antibodies can improve the efficiency of melanoma therapies. Recently, several mAbs, such as nivolumab, pembrolizumab, and ipilimumab, were approved for the immunotherapy of melanoma. The antibodies inhibit immune checkpoint receptors such as CTL4 and pd-1. Another therapeutic strategy for the treatment of melanoma is cancer vaccines, which improve clinical outcomes in patients. The combination therapy using antibodies and gene vaccine give us a new perspective in the treatment of melanoma patients. Herein, we present the recent progressions in the melanoma immunotherapy, especially dendritic cells mRNA vaccines by reviewing recent literature.  相似文献   
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The preventive effect of vitamin D against breast cancer can be influenced by gene polymorphisms. This study aimed to investigate the association between serum level of 25(OH) vitamin D and FTO genotype in breast cancer patients. A cross-sectional study was carried out on 180 newly diagnosed patients with breast cancer in Tehran, Iran. The blood samples were collected from the participants in order to assess the FTO gene rs9939609 polymorphism by the tetra-primer amplification refractory mutation system (Tetra-ARMS) PCR method. The serum level of 25(OH) vitamin D was measured using the direct competitive enzyme-linked immunosorbent assay (ELISA) method. The association between vitamin D and the FTO genotype in patients with breast cancer was assessed after adjustment for cofounders. The frequency of TT, AT and AA genotypes in the breast cancer patients were 43% (n = 77), 49% (n = 89) and 8% (n = 14), respectively. All patients with higher than 40 ng/dl of serum 25(OH) vitamin D had one or two copies of FTO rs9939609 risk allele (p = 0.019). No linear association was found between the number of FTO risk allele and the level of serum vitamin D. All patients with high serum level of 25(OH) vitamin D had one or two copies of FTO rs9939609 risk allele. FTO gene polymorphisms may counteract the beneficial effects of vitamin D in breast cancer prevention. Further studies can help to better understand the genetic factors predisposing to breast cancer and their effect on the association between vitamin D and breast cancer.  相似文献   
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Background:Memory-dependent psychological behaviors have an important role in life. Memory strengthening in adulthood to prevent its defects in aging is a significant issue. The ghrelin endogenous hormone improves memory by targeting glutamatergic and serotonergic circuits. Also, citicoline, a memory strengthening drug in aging, is not recommended to adults due to its side effects. The current study aims to test that ghrelin treatment, like citicoline, would improve passive avoidance memory via expression of the genes encoding the N-methyl-D-aspartate receptor (NMDAR1) and the serotonin receptor 1A (HTR1α) involved in this process.Methods:Five groups of adult male rats received (1) saline (as control), (2) 0.5 mg/kg citicoline, or (3-5) 0.3, 1.5, and 3 nmol/μl ghrelin). The rats received the drugs via intra-hippocampal injection. Passive avoidance memory was determined using a shuttle box device. The latency to enter the dark chamber before (IL) and after (RL) injection and the total duration of the animal''s presence in the light compartment (TLC) were evaluated. Then, the gene expression rates of NMDAR1 and HTR1α were measured by the Real-Time PCR. Results:Ghrelin and citicoline had some similar and significant effects on passive avoidance memory, and both increased NMDAR1 and decreased HTR1α expression.Conclusion:Ghrelin, like citicoline, improves passive avoidance learning by altering the NMDAR1 and HTR1α expression in the hippocampusKey Words: Citicoline, Ghrelin, HTR1α, Intrahippocampal injection, NMDAR1, Passive Avoidance Memory  相似文献   
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Ovarian cancer (OC) is the fifth leading cause of cancer-related death among women. The high mortality rate is due to lack of early symptoms, late diagnosis, limited treatment options, and also emerging of drug resistance. Todays, molecular markers have become promising in tumor-targeted therapy. Several molecular markers have been known in OC immunotherapy. Identification of the specific molecular markers with prognostic significance is interested. CD24 is a small sialoglycoprotein which is localized in lipid rafts through its glycosylphosphatidylinositol (GPI) anchor. It has been reported that CD24 is overexpressed in many cancers including OC. Also, CD24 is identified as a cancer stem cell marker in OC. The CD24 expression is associated with the development, invasion, and metastasis of cancer cells. The exact role of CD24 in cancer cells is not clearly understood. Recently, CD24 has been identified as an independent prognostic marker of survival in patients with OC. In this study, we reviewed the molecular targets in OC immune-targeted therapy and also presented an overview of the new molecular marker CD24 and its association with the OC by reviewing the recent literature.  相似文献   
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