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161.
Two single nucleotide polymorphisms (SNP, rs8099917, rs12979860) near the IL28B gene have been illustrated as outcome predictors of hepatitis C virus (HCV) treatment with pegylated interferon/ribavirin. The aim of the present study was to design a simple tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS-PCR) for the evaluation of the rs8099917 IL28B gene polymorphism. We efficiently designed a T-ARMS-PCR for detection of rs8099917 IL28B. Using this method, we genotyped 83 subjects with NAFLD (nonalcoholic fatty liver disease) and 93 healthy subjects. No significant differences were found in allelic and genotypic frequencies of rs8099917 IL28B gene polymorphism between NAFLD subjects and controls. The frequency of minor allele (G allele) was 0.13 in healthy and 0.19 in NAFLD subjects. In conclusion, we designed a simple, inexpensive, and reproducible T-ARMS-PCR for detection of rs8099917 IL28B polymorphism which can be used for routine assay. In addition, we found that rs8099917 polymorphism is not a risk factor for predisposition to NAFLD in a sample of Iranian population. Larger studies with different ethnics are required to validate our findings.  相似文献   
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Previously, we discovered linomide analogues as novel HIV-1 integrase (IN) inhibitors. Here, to make possible structure–activity relationships, we report on the design and synthesis of a series of substituted dihydroquinoline-3-carboxylic acids. The crystal structure of the representative compound 2c has also been solved. Among the eight new analogues, 2e showed a potency in inhibiting IN strand transfer catalytic activity similar to the reference diketo acid inhibitor L-731,988 (IC50 = 0.9 μM vs. 0.54 μM, for 2e and L-731,988, respectively). Furthermore, none of the compounds showed significant cytotoxicity in two tested cancer cell lines. These compounds represent an interesting prototype of IN inhibitors, potentially involved in a metal chelating mechanism, and further optimization is warranted.  相似文献   
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The endoplasmic reticulum (ER) is the major site for folding and sorting of newly synthesized secretory cargo proteins. One central regulator of this process is the quality control machinery, which retains and ultimately disposes of misfolded secretory proteins before they can exit the ER. The ER quality control process is highly effective and mutations in cargo molecules are linked to a variety of diseases. In mammalian cells, a large number of secretory proteins, whether membrane bound or soluble, are asparagine (N)-glycosylated. Recent attention has focused on a sugar transferase, UDP-Glucose: glycoprotein glucosyl transferase (UGGT), which is now recognized as a constituent of the ER quality control machinery. UGGT is capable of sensing the folding state of glycoproteins and attaches a single glucose residue to the Man9GlcNAc2 glycan of incompletely folded or misfolded glycoproteins. This enables misfolded glycoproteins to rebind calnexin and reenter productive folding cycles. Prolonging the time of glucose addition on misfolded glycoproteins ultimately results in either the proper folding of the glycoprotein or its presentation to an ER associated degradation machinery.  相似文献   
166.
A primary concern of modern plant breeding is that genetic diversity has decreased during the past century. This study set out to explore changes in genetic variation during 84 years of breeding by investigating the germination-related traits, inter-simple sequence repeat (ISSR) fingerprinting and osmotic stress tolerance of 30 Iranian wheat (Triticum aestivum L.) cultivars. Seeds were planted under control and osmotic stress (?2, ?4 and ?6 bar) in three replications. The ISSR experiment was carried out using 32 different primers. Genotypes were divided into two groups (old and new) each containing 15 members. The results of ANOVA showed that highly significant differences existed among genotypes and among growth conditions. The results showed that during breeding in some traits such as coleoptile length and seedling vigor index, a significant decrease has been occurred. New cultivars had a mean coleoptile length of 33 mm, shorter than that of old cultivars (42 mm) under osmotic stress of ?6 bar. Genetic variance of root length, shoot length and seedling vigor index for old cultivars were 1.59, 1.93 and 45,763, respectively, significantly higher than those for new cultivars (0.55, 1.08 and 27,996, respectively). This difference was also verified by ISSR results as the polymorphism information content was 0.28 in old cultivars, higher than that of new cultivars (0.26). These results prove this claim that during breeding, genetic diversity has decreased for many germination-related traits and breeders are better to pay more attention to genetic diversity.  相似文献   
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Intrauterine infection is a major cause of immune imbalance at the maternal-fetal interface, which leads to spontaneous abortion, premature rupture of the fetal membranes, and preterm birth. Human amniotic epithelial cells (hAECs) play a fundamental role in the maintenance of pregnancy. We hypothesize that bacteria influence the immunomodulatory effects of hAECs through stimulation of Toll-like receptors (TLRs). Here, we investigated how lipopolysaccharide (LPS) as a bacterial component affects anti-inflammatory and pro-inflammatory cytokines production of hAECs. Human placentas were obtained from six healthy pregnant women and hAECs were isolated. The phenotypic characteristics of hAECs were determined by flow cytometry. The hAECs (4?×?105 cells/ml) were cultured in the presence or absence of LPS (5?μg/ml). The viability of the cells was assessed and culture supernatants of hAECs were collected after 24, 48 and 72?h of incubation. The levels of transforming growth factor-beta1 (TGF-β1), interleukin-4 (IL-4), tumor necrosis factor-alpha (TNF-α), interleukin-17?A (IL-17A), and interferon-gamma (IFN-γ) were measured by ELISA. Our data showed that LPS treatment did not affect the viability of hAECs, while had a stimulatory effect on TGF-β1 production of hAECs (p?<?0.001). A significant reduction in IL-4 production of LPS-stimulated hAECs was observed (p?<?0.05). LPS enhanced the production of TNF-α and IL-17?A of hAECs (p?<?0.05–0.0001). The IFN-γ level was only detectable in two culture supernatants of hAECs, and the level was unchanged after stimulation with LPS. Based on these findings, LPS may play a pivotal role in immune imbalance at the feto-maternal interface through affecting anti-inflammatory and pro-inflammatory cytokines production of hAECs.  相似文献   
169.
Magnetic iron oxide nanoparticles are a well-explored class of nanomaterials known for their high magnetization and biocompatibility. They have been used in various biomedical applications such as drug delivery, biosensors, hyperthermia, and magnetic resonance imaging (MRI) contrast agent. It is necessary to surface modify the nanoparticles with a biocompatible moiety to prevent their agglomeration and enable them to target to the defined area. Dendrimers have attracted considerable attention due to their small size, monodispersed, well-defined globular shape, and a relative ease incorporation of targeting ligands. In this study, superparamagnetic iron oxide nanoparticles were synthesized via a coprecipitation method. The magnetic nanoparticles (MNPs) had been modified with (3-aminopropyl) triethoxysilane, and then polyamidoamine functionalized MNPs had been synthesized cycling. Various characterization techniques had been used to reveal the morphology, size, and structure of the nanoparticles such as scanning electron microscopy, transmission electron microscope, X-ray diffraction analysis, and vibrating sample magnetometer, Fourier-transform infrared spectroscopy and zeta potential measurements. In addition, the cytotoxicity property of G3–dendrimer functionalized MNPs were evaluated using 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide assay which confirmed the biocompatibility of the nanocomposites. Dendrimer functionalized MNPs are able to act as contrast agents for MRI and magnetic fluid hyperthermia mediators. A superior heat generation was achieved for the given concentration according to the hyperthermia results. MRI results show that the synthesized nanocomposites are a favorable option for MRI contrast agent. We believe that these dendrimer functionalized MNPs have the potential of integrating therapeutic and diagnostic functions in a single carrier.  相似文献   
170.
Multiple sclerosis (MS) is a devastating autoimmune disease of the central nervous system associated with demyelination and axonal injury. This study was designed to find potential lncRNAs and their targets that are associated with the molecular basis of MS pathogenesis. In this study, peripheral blood samples were obtained from 50 relapsing-remitting MS (RR-MS) patients and 50 healthy controls. lncRNAs and their target were selected for validation using TaqMan Real-Time PCR. Interactions were studied based on approaches that used to investigation biological functions and signaling pathways affected by differentially expressed messenger RNAs (mRNAs). The results of this study indicate an increase in the expression of HUR1 (p = 0.0001), CPSF7 (p = 0.02), and reduction of CSTF2 expression (p = 0.04). Also, an increase in the expression of OIP5-AS1 (p = 0.01) was observed in men less than 30 years old. We performed a comparative analysis of the long noncoding RNAs (lncRNAs), and then we ranked them as candidate biomarkers according to a decreasing area under the receiver operating characteristic (ROC) curve (AUC) and plotted the results. Dysregulation of lncRNA expression has been linked to diseases. Further studies on the HUR1 gene can be used as diagnostic tools for the identification of high-risk individuals in families with a history of disease before, during, and even after treatment. Our data uncovered the expression profiles of lncRNAs and mRNAs in MS patients, which will help delineate the molecular mechanisms in MS pathogenesis. However, further studies need to determine the precise role of these genes in the pathological process in MS.  相似文献   
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