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41.
According to our analysis of literature sources on the family Hydraenidae (Coleoptera: Staphylinoidea) of Iran, it is represented by 67 species and three genera: Hydraena Kugelann, 1794 (21 species), Limnebius Leach, 1815 (six species) and Ochthebius Leach, 1815 (40 species). Twenty-two species are supposed to be endemic to Iran. Here, for the first time, we summarize species distribution data in Iranian provinces and present them in a checklist of Iranian Hydraenidae. We also present two additional species lists: one with incorrect records (one species and one subspecies) and the other with unidentified species.  相似文献   
42.
The current study was conducted to assess the relationship between testicular cells in spermatogenesis, through which the production of healthy and mature sperm is essential. However, it seems necessary to obtain more information about the three-dimensional pattern of the testis cells arrangement, which is directly related to the function of the testis after induction of diabetes. Twelve adult mice (28-30 g) were assigned into two experimental groups: (1) control and (2) diabetic (40 mg/kg STZ). The epididymal sperm collected from the tail of the epididymis and testes samples were taken for stereology, immunocytochemistry and RNA extraction. Our data showed that diabetes could notably decrease the number of testicular cells, together with a reduction of total sperm count. In addition, the results from the second-order stereology indicated the significant changes in the spatial arrangement of Sertoli cells and spermatogonial cells in the diabetic groups, in comparison with the control (P < .05). Moreover, the immunohistochemistry results showed a significant reduction in Sex-determining Region Y (SRY) box 9 gene (SOX9), vimentin, occludin, and connexin-43 positive cells in the diabetic groups compared with the control (P < .05). Furthermore, our data showed that the expression of steroidogenic acute regulatory protein steroidogenic acute regulatory protein (StAR) and peripheral benzodiazepine receptor peripheral benzodiazepine receptor (PBR) was significantly reduced in the diabetic groups, in comparison with the control (P < .05). These findings suggest that structural and functional changes of testis cells after induction of diabetes cause the alterations in the spatial arrangement of Sertoli and spermatogonial cells, ultimately influencing the normal spermatogenesis in mice.  相似文献   
43.
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   
44.
Transforming growth factor-beta 1 (TGF-beta 1) possesses highly potent, diverse and often opposing cell-specific activities, and has been implicated in the regulation of a variety of physiologic and developmental processes. To determine the effects of in vivo overexpression of TGF-beta 1 on mammary gland function, transgenic mice were generated harboring a fusion gene consisting of the porcine TGF-beta 1 cDNA placed under the control of regulatory elements of the pregnancy-responsive mouse whey-acidic protein (WAP) gene. Females from two of four transgenic lines were unable to lactate due to inhibition of the formation of lobuloalveolar structures and suppression of production of endogenous milk protein. In contrast, ductal development of the mammary glands was not overtly impaired. There was a complete concordance in transgenic mice between manifestation of the lactation-deficient phenotype and expression of RNA from the WAP/TGF-beta 1 transgene, which was present at low levels in the virgin gland, but was greatly induced at mid-pregnancy. TGF-beta 1 was localized to numerous alveoli and to the periductal extracellular matrix in the mammary gland of transgenic females late in pregnancy by immunohistochemical analysis. Glands reconstituted from cultured transgenic mammary epithelial cells duplicated the inhibition of lobuloalveolar development observed in situ in the mammary glands of pregnant transgenic mice. Results from this transgenic model strongly support the hypothesis that TGF-beta 1 plays an important in vivo role in regulating the development and function of the mammary gland.  相似文献   
45.
Cross seeding between amyloidogenic proteins in the gut is receiving increasing attention as a possible mechanism for initiation or acceleration of amyloid formation by aggregation‐prone proteins such as αSN, which is central in the development of Parkinson''s disease (PD). This is particularly pertinent in view of the growing number of functional (i.e., benign and useful) amyloid proteins discovered in bacteria. Here we identify two amyloidogenic proteins, Pr12 and Pr17, in fecal matter from PD transgenic rats and their wild type counterparts, based on their stability against dissolution by formic acid (FA). Both proteins show robust aggregation into ThT‐positive aggregates that contain higher‐order β‐sheets and have a fibrillar morphology, indicative of amyloid proteins. In addition, Pr17 aggregates formed in vitro showed significant resistance against FA, suggesting an ability to form highly stable amyloid. Treatment with proteinase K revealed a protected core of approx. 9 kDa. Neither Pr12 nor Pr17, however, affected αSN aggregation in vitro. Thus, amyloidogenicity does not per se lead to an ability to cross‐seed fibrillation of αSN. Our results support the use of proteomics and FA to identify amyloidogenic protein in complex mixtures and suggests that there may be numerous functional amyloid proteins in microbiomes.  相似文献   
46.
Ionic liquid pretreatment of biomass has been shown to greatly reduce the recalcitrance of lignocellulosic biomass, resulting in improved sugar yields after enzymatic saccharification. However, even under these improved saccharification conditions the cost of enzymes still represents a significant proportion of the total cost of producing sugars and ultimately fuels from lignocellulosic biomass. Much of the high cost of enzymes is due to the low catalytic efficiency and stability of lignocellulolytic enzymes, especially cellulases, under conditions that include high temperatures and the presence of residual pretreatment chemicals, such as acids, organic solvents, bases, or ionic liquids. Improving the efficiency of the saccharification process on ionic liquid pretreated biomass will facilitate reduced enzyme loading and cost. Thermophilic cellulases have been shown to be stable and active in ionic liquids but their activity is typically at lower levels. Cel5A_Tma, a thermophilic endoglucanase from Thermotoga maritima, is highly active on cellulosic substrates and is stable in ionic liquid environments. Here, our motivation was to engineer mutants of Cel5A_Tma with higher activity on 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) pretreated biomass. We developed a robotic platform to screen a random mutagenesis library of Cel5A_Tma. Twelve mutants with 25–42% improvement in specific activity on carboxymethyl cellulose and up to 30% improvement on ionic-liquid pretreated switchgrass were successfully isolated and characterized from a library of twenty thousand variants. Interestingly, most of the mutations in the improved variants are located distally to the active site on the protein surface and are not directly involved with substrate binding.  相似文献   
47.
Prediction of chiral separation for a compound using a chiral selector is an interesting and debatable work. For this purpose, in this study 23 chiral basic drugs with different chemical structures were selected as model solutes and the influence of their chemical structures on the enantioseparation in the presence of maltodextrin (MD) as chiral selector was investigated. For chiral separation, a 100‐mM phosphate buffer solution (pH 3.0) containing 10% (w/v) MD with dextrose equivalent (DE) of 4‐7 as chiral selector at the temperature of 25°C and voltage of 20 kV was used. Under this condition, baseline separation was achieved for nine chiral compounds and partial separation was obtained for another six chiral compounds while no enantioseparation was obtained for the remaining eight compounds. The results showed that the existence of at least two aromatic rings or cycloalkanes and an oxygen or nitrogen atom or –CN group directly bonded to the chiral center are necessary for baseline separation. With the obtained results in this study, chiral separation of a chiral compound can be estimated with MD‐modified capillary electrophoresis before analysis. This prediction will minimize the number of preliminary experiments required to resolve enantiomers and will save time and cost. Chirality 26:620–628, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
48.
Here, we have synthesized Ag2O3-ZnO nanocones (NCs) by a wet-chemical route using reducing agents at low temperature. The structural, optical and morphological properties of Ag2O3-ZnO NCs were investigated by several conventional techniques such as powder XRD, XPS, FESEM, XEDS, FTIR and UV/vis. spectroscopy. The analytical parameters of prepared NCs were also calculated for a selective detection of divalent cobalt [Co(II)] prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES). The selectivity of NCs toward various metal ions, including Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Ni(II), and Zn(II) was studied. Results of the selectivity study demonstrated that Ag2O3-ZnO NC phase was the most selective towards Co(II) ion. The uptake capacity for Co(II) ion was experimentally calculated to be ∼76.69 mgg−1. Moreover, adsorption isotherm data provided that the adsorption process was mainly monolayer on homogeneous adsorbent surfaces of Ag2O3-ZnO NCs. Kinetic study revealed that the adsorption of Co(II) on Ag2O3-ZnO NCs phase followed the pseudo-second-order kinetic model. In addition, thermodynamic results provided that the adsorption mechanism of Co(II) ions on Ag2O3-ZnO NCs was a spontaneous process and thermodynamically favorable. Finally, the proposed method was validated by applying it to real environmental water samples with reasonable results.  相似文献   
49.

Background

Nucleic acids based therapeutic approaches have gained significant interest in recent years towards the development of therapeutics against many diseases. Recently, research on aptamers led to the marketing of Macugen®, an inhibitor of vascular endothelial growth factor (VEGF) for the treatment of age related macular degeneration (AMD). Aptamer technology may prove useful as a therapeutic alternative against an array of human maladies. Considering the increased interest in aptamer technology globally that rival antibody mediated therapeutic approaches, a simplified selection, possibly in one-step, technique is required for developing aptamers in limited time period.

Principal Findings

Herein, we present a simple one-step selection of DNA aptamers against α-bungarotoxin. A toxin immobilized glass coverslip was subjected to nucleic acid pool binding and extensive washing followed by PCR enrichment of the selected aptamers. One round of selection successfully identified a DNA aptamer sequence with a binding affinity of 7.58 µM.

Conclusion

We have demonstrated a one-step method for rapid production of nucleic acid aptamers. Although the reported binding affinity is in the low micromolar range, we believe that this could be further improved by using larger targets, increasing the stringency of selection and also by combining a capillary electrophoresis separation prior to the one-step selection. Furthermore, the method presented here is a user-friendly, cheap and an easy way of deriving an aptamer unlike the time consuming conventional SELEX-based approach. The most important application of this method is that chemically-modified nucleic acid libraries can also be used for aptamer selection as it requires only one enzymatic step. This method could equally be suitable for developing RNA aptamers.  相似文献   
50.
During development, cortical plasticity is associated with the rearrangement of excitatory connections. While these connections become more stable with age, plasticity can still be induced in the adult cortex. Here we provide evidence that structural plasticity of?inhibitory synapses onto pyramidal neurons is?a major component of plasticity in the adult neocortex. In?vivo two-photon imaging was used to monitor the formation and elimination of fluorescently labeled inhibitory structures on pyramidal neurons. We find that ocular dominance plasticity in the adult visual cortex is associated with rapid inhibitory synapse loss, especially of those present on dendritic spines. This occurs not only with monocular deprivation but also with subsequent restoration of binocular vision. We propose that in the adult visual cortex the experience-induced loss of inhibition may effectively strengthen specific visual inputs with limited need for rearranging the excitatory circuitry.  相似文献   
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