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1.
The nature of the anion–π interaction has been investigated by carrying out ab initio calculations of the complexes of coinage metal anions (Au?, Ag?, and Cu?) with different kinds of π-systems. The binding energies indicate that gold anion has the highest and copper anion has the lowest affinity for interactions with π-systems. Different aspects of the anion–π interaction in these systems have been investigated, including charge-transfer effects (using the Merz–Kollman method), “atoms-in-molecules” (AIM) topological parameters, and interaction energies (using energy decomposition analysis, EDA). Our results indicated that, for most M?···π interactions, the electrostatic term provides the dominant contribution, whereas polarization, charge transfer, and dispersion effects contribute less than 25 % of the interaction. We believe that the present results should lead to a greater understanding of the basis for anion–π interactions of coinage metal anions.  相似文献   
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Multidrug-resistant tuberculosis (MDR-TB) is caused by bacteria that are resistant to the most effective anti TB drugs (Isoniazid and Rifampicin) with or without resistance to other drugs. Novel intervention strategies to eliminate this disease based on finding proteins can be used for designing new drugs or new and reliable kits for diagnosis. The aim of this study was to compare the protein profile of MDR-TB with sensitive isolates. Two-dimensional gel electrophoresis (2DE) along with mass spectrometry is a powerful and effective tool to identification and characterization of Mycobacterium tuberculosis. Two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was used for diagnosis and comparison of proteins. We identified 14 protein spots in MDR-TB isolates that 2DE analysis showed these spots absent in M. tuberculosis sensitive isolates (Rv1876, Rv0379, Rv0147, Rv2031c, Rv3597c, Rv1886c, MT0493, Rv0440, Rv3614c, Rv1626, Rv0443, Rv0475, Rv3057 and unknown protein. The results showed 22 protein spots which were up regulated (or expressed) by the MDR-TB isolates, (Rv1240, Rv3028c, Rv2971, Rv2114c, Rv3311, Rv3699, Rv1023, Rv1308, Rv3774, Rv0831c, Rv2890c, Rv1392, Rv0719, Rv0054, Rv3418c, Rv0462, Rv2215, Rv2986c, Rv3248c and Rv1908c)). Two up regulated protein spots were identified in sensitive isolate (Rv1133c and Rv0685). These data will provide valuable clues in further investigation for suitable TB rapid tests or drug targets against drug resistant and sensitive of M. tuberculosis.  相似文献   
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Elicitation effect of silver nano particles (AgNPs) and triggering of defence system by production of hydrogen peroxide (H2O2) as a signaling molecule in the regulation of the activity of stress-related enzymes and production of Taxol was evaluated in suspension- cultured hazel cells (Corylus avellana L.). The cells were treated with different concentrations of AgNPs (0, 2.5, 5, and 10 ppm), in their logarithmic growth phase (d7) and were harvested after 1 week. Treatment of hazel cells with AgNPs decreased the viability of the cells. Also the results showed that while the activity of certain radical scavenging enzymes in particular of catalase and peroxidase increased by 2.5 and 5 ppm AgNPs, the activity of superoxide dismutase decreased in these treatments. The highest activity of ascorbate peroxidase was observed in 10 ppm AgNPs treatments. This treatment also showed the highest contents of H2O2 and phenolic compounds, as well as the highest activity of phenylalanine ammonialyase. According to the results, 5 ppm AgNPs was the best concentration for elicitation of hazel cells to produce efficient amounts of H2O2 in order for stimulation of antioxidant defence system, production of Taxol at the highest capacity of the cells, meanwhile reserving their viability.  相似文献   
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We used fluorescently labeled phalloidin to examine the subumbrellar musculature of the scyphozoan jellyfish Aurelia aurita in a developmental series from ephyra to adult medusa. In the ephyra, the swim musculature includes a disc‐like sheet of circular muscle, in addition to two radial bands of muscle in each of the eight ephyral arms. The radial muscle bands join with the circular muscle, and both circular and radial muscle act together during each swim contraction. As the ephyra grows into a juvenile medusa, arms tissue is resorbed as the bell tissue grows outward, so eventually, the ephyral arms disappear. During this process, the circular muscle disc also grows outward and the radial muscle bands of the arms also disappear. At this time, a marginal gap appears at the bell margin, which is devoid of circular muscle cells, but has a loose arrangement of radial muscle fibers. This marginal gap is preserved as the medusa grows, and contributes to the floppy nature of the bell margin. Radial distortions in the circular muscle layer involve muscle fibers that run in random directions, with a primarily radial orientation. These are believed to be remnants of the radial muscle of the ephyral arms, and the distortions decrease in number and extent as the medusa grows. Since the mechanics of swimming changes from drag‐based paddling in the ephyra to marginal rowing in the adult medusa, the development of the marginal gap and the presence of radial distortions should be considered in terms of this mechanical transition.  相似文献   
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In animal models, STAT3 action in the hypothalamus and liver appears essential for normal body weight and glucose homeostasis in response to insulin. We hypothesized that variation in the STAT3 gene may be associated with body fat and/or insulin resistance in the general population. Five tagging SNPs spanning the STAT3 gene, rs8074524, rs2293152, rs2306580, rs6503695, and rs7211777 were genotyped in 2776 white female twins (mean age, 47.4+/-12.5 yrs) from the St Thomas' United Kingdom Adult Twin Registry (Twins UK). Minor allele frequencies were as follows: rs8074524 (0.19), rs2293152 (0.37), rs2306580 (0.06), rs6503695 (0.35), and rs7211777 (0.34). The minor allele of rs2293152 was associated with higher homeostasis model assessment index of insulin resistance (p=0.013) in the full cohort and confirmed in sib-transmission/disequilibrium test (TDT): (p=0.015; n=60). However, there were no associations with fasting serum insulin or glucose or with obesity variables. Although defective STAT3 action results in obesity and insulin resistance in animal models, we failed to establish any indicative associations with common SNPs in this human study.  相似文献   
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Osteoarthritis (OA) is the most common type of arthritis and no longer is considered as an absolute consequence of joint mechanical use (wear and tear); rather recent data demonstrate the pivotal role of inflammatory mediators in the development and progression of this disease. This multifactorial disease results from several environmental and inherited factors. Genetic cannot solely explain all the contribution share of inheritance and, this way, it is speculated that epigenetics can play a role, too. Moreover, environmental factors can induce local epigenetic changes. The epigenetic contribution to OA pathogenesis occurs at all of its levels, DNA methylation, histone modification, microRNA, and long noncoding RNA. In fact, during early phases of OA pathogenesis, environmental factors employ epigenetic mechanisms to provide a positive feedback for the OA-related pathogenic mechanisms and pathways with an ultimate outcome of a well-established clinical OA. These epigenetic changes stay during clinical disease and prevent the body natural healing and regenerative processes to work properly, resulting in an incurable disease condition. In this review article, we aimed to have an overview on the studies performed with regard to understanding the role of epigenetics in the etiopathogenesis of OA and highlighted the importance of such kind of regulatory mechanisms within this context.  相似文献   
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Human influenza A viruses (IAVs) cause global pandemics and epidemics, which remains a nonignorable serious concern for public health worldwide. To combat the surge of viral outbreaks, new treatments are urgently needed. Here, we design a new vaccine based on virus-like particles (VLPs) and show how intranasal administration of this vaccine triggers protective immunity, which can be exploited for the development of new therapies. H1N1 VLPs were produced in baculovirus vectors and were injected into BALB/c mice by the intramuscular (IM) or intranasal (IN) route. We found that there were significantly higher inflammatory cell and lymphocyte concentrations in bronchoalveolar lavage samples and the lungs of IN immunized mice; however, the IM group had little signs of inflammatory responses. On the basis of our results, immunization with H1N1 influenza VLP elicited a strong T cell immunity in BALB/c mice. Despite T cell immunity amplification after both IN and IM vaccination methods in mice, IN-induced T cell responses were significantly more intense than IM-induced responses, and this was likely related to an increased number of both CD11bhigh and CD103+ dendritic cells in mice lungs after IN administration of VLP. Furthermore, evaluation of interleukin-4 and interferon gamma cytokines along with several chemokine receptors showed that VLP vaccination via IN and IM routes leads to a greater CD4+ Th1 and Th2 response, respectively. Our findings indicated that VLPs represent a potential strategy for the development of an effective influenza vaccine; however, employing relevant routes for vaccination can be another important part of the universal influenza vaccine puzzle.  相似文献   
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We have developed a Mathematica application package to perform dynamic simulations of the red blood cell (RBC) metabolic network. The package relies on, and integrates, many years of mathematical modeling and biochemical work on red blood cell metabolism. The extensive data regarding the red blood cell metabolic network and the previous kinetic analysis of all the individual components makes the human RBC an ideal 'model' system for mathematical metabolic models. The Mathematica package can be used to understand the dynamics and regulatory characteristics of the red blood cell.  相似文献   
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