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111.
Background:Systemic lupus erythematosus (SLE) is an autoimmune disease with inflammatory nature. One of the leading causes of death in SLE patients is cardiovascular (CVS) morbidity. MiRNA-24 is highly expressed in vascular endothelial cells (VECs). This dysregulated expression pattern is associated with dysfunction or even damage of VECs and leads to the occurrence of cardiovascular diseases. YKL- 40 is an inflammatory glycoprotein involved in the pathogenesis of endothelial dysfunction and thereby atherosclerosis. In this work, we aimed at illustrating the possible role of miR-24 and its target YKL-40 in the pathogenesis of the CVS morbidity associated with SLE.Methods:This work was conducted on 40 SLE patients and 40 healthy controls. Quantitative real-time PCR (qPCR) was done to estimate the expression level of miRNA-24 in serum. In addition, we measured the serum level of YKL-40 using ELISA.Results:miR-24-fold change was found to be down-regulated, whereas serum YKL- 40 was up-regulated among SLE patients with observed significant and negative correlation between the two parameters.Conclusion:Our study provided an insight about the role of miR-24 and its target serum YKL-40 protein in the development of SLE-related inflammation and atherosclerosis.Key Words: miRNA-24, SDC-1, SLE, VCAM, YKL-40  相似文献   
112.
Uncontrolled inflammation in systemic lupus erythematosus (SLE) could cause dysfunction in multiple organs. T helper 17 (Th17) cells are a main branch of inflammatory responses in the pathogenesis of SLE, and by producing interleukin 17 (IL-17), represent a major functional tool in the progression of inflammation. Animal models provide a special field for better studies of the pathogenesis of diseases. Tolergenic probiotics could decrease inflammation in autoimmune diseases by modulating the immune system and maintaining homeostasis. The aim of this project was to evaluate the effects of Lactobacillus rhamnosus and Lactobacillus delbrueckii on Th17 cells and their related mediators in a pristane-induced BALB/c mice model of SLE. The mice were divided into pretreatment groups, which received probiotics or prednisolone at Day 0, and treatment groups, which received probiotics and prednisolone 2 months after injection. The presence of antinuclear antibody (ANA), anti-double-stranded DNA (anti-dsDNA), and anti-ribonucleoprotein (anti-RNP) and lipogranuloma was evaluated; also, the population of Th1–Th17 cells as well as interferon γ (IFN-γ), IL-17, and IL-10 levels, and the expression of RAR-related orphan related receptor gamma (RORγt) and IL-17 were determined. We observed that probiotics and prednisolone could delay SLE in pretreatment and treatment mice groups, with a reduction in ANA, anti-dsDNA, anti-RNP, and mass of lipogranuloma. Probiotics and prednisolone decreased the population of Th1–Th17 cells and reduced IFN-γ and IL-17 as inflammatory cytokines in the pretreatment and treatment groups in comparison with SLE-induced mice. Our results indicated that, due to their anti-inflammatory properties and reduction of Th17, Th1, and cytotoxic T lymphocyte (CTL) cells, the use of these probiotics could probably represent a new tool for the better management of SLE.  相似文献   
113.
The new natural caffeoyl esters, 3,6-di-O-caffeoyl-(alpha/beta)-glucose and 1-O-caffeoyl-beta-xylose, together with the hitherto unknown natural tannin, 2,3-O-hexahydroxydiphenoyl-4,6-O-sanguisorboyl-(alpha/beta)-glucose, have been isolated from the aqueous alcohol aerial part extract of Rubus sanctus. Establishment of all structures was based on the chemical and spectral evidence, including ESI-MS and 2D NMR.  相似文献   
114.
The development of high-throughput sequencing technologies has transformed our capacity to investigate the composition and dynamics of the microbial communities that populate diverse habitats. Over the past decade, these advances have yielded an avalanche of metagenomic data. The current stage of “van Leeuwenhoek”–like cataloguing, as well as functional analyses, will likely accelerate as DNA and RNA sequencing, plus protein and metabolic profiling capacities and computational tools, continue to improve. However, it is time to consider: what’s next for microbiome research? The short pieces included here briefly consider the challenges and opportunities awaiting microbiome research.
This Perspective is part of the “Where next?” Series.
Soon, we will enter an era when “the number of population genomes deposited in public databases will dwarf those from isolates and single cells” (Gene Tyson). Clearly, as all authors noted in the following, our focus will move from describing the composition of microbial communities to elucidating the principles that govern their assembly, dynamics, and functions. How will such principles be discovered? Elhanan Borenstein proposes that a systems biology–based approach, particularly the development of mathematical and computational models of the interactions between the specific community components, will be critical for understanding the function and dynamics of microbiomes. Evolutionary biologists Howard Ochman and Andrew Moeller want to decipher how microbial assemblies evolve but challenge us to also consider the role of microbial communities in organismal evolution, and they make the exciting prediction that microbes will be implicated in the evolution of eusociality and cooperation. Brett Finlay underscores the need for deciphering the mechanistic bases—particularly the chemical/metabolite signals—for interactions between members of microbial communities and their hosts. He emphasizes how this knowledge will enable creation of new tools to manipulate the microbiota, a key challenge for future investigation. Heidi Kong also encourages deciphering the mechanisms that underlie associations between particular skin surfaces and disorders and their respective microbiota. Jeffrey Gordon considers several intriguing opportunities as well as challenges that manipulation of the gut microbiota presents for improved human nutrition and health. Finally, Karen Nelson, Karim Dabbagh and Hamilton Smith suggest that using synthetic genomes to create novel microbes or even synthetic microbiomes offers a new way to engineer the microbiota. Overall, future microbiome research regarding the molecules and mechanisms mediating interactions between members of microbial communities and their hosts should lead to discovery of exciting new biology and transformative therapeutics.  相似文献   
115.
116.
The target of our current work was designed to prepare titanium oxide doped silver nanoparticles (Ag/TiO2NPs) and their impact on the functionalization of cotton fabrics. Additionally, the effect of Ag/TiO2NPs was compared with the individually prepared silver nanoparticles (AgNPs) and titanium oxide nanoparticles (TiO2NPs). In this work, AgNPs were prepared in the solid state using arabic gum as efficient stabilizing and reducing agent. Then, two concentrations of the as-synthesized nanoparticles were used to functionalize the cotton fabrics by pad-dry-cure treatment in the presence of fixing agent to increase the durability of treated cotton fabrics against vigorous washing cycles. The findings implied that the as-prepared nanoparticles were successfully synthesized in nano-size with spherical shape and homogeneity. The efficacy of the functionalized cotton fabrics with those nanoparticles were evaluated in terms of multifunctional properties including antimicrobial and ultraviolet protection factor (UPF) and the mechanical features before and after many washing cycles; 10, 15 and 20 times. The resultant also proved that Ag/TiO2NPs-treated cotton fabrics exhibited the greater values of both antimicrobial and UPF properties with enhancement in the tensile strength and elongation features. Thus, the combination between these two nanoparticles through doping reaction is suitable for imparting superior antimicrobial properties against the four tested microbial species (Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger) and good UPF properties. Depending on the promising obtained results of the multi-finishing fabrics, these nanoparticles of Ag/TiO2NPs can be applied for the production of an efficient medical clothes for doctors, nurses and bed sheets for patients in order to kill and prevent the spread of bacteria and then, reduce the transmission of infection to others.  相似文献   
117.
Lactobacillus acidophilus DSM 20079 is the producer of a novel bacteriocin termed acidocin D20079. In this paper, mode of action using three various concentrations of acidocin D20079 (2,048, 128 and 11.3 AU/ml) was determined against an indicator strain L. delbrueckii subsp. lactis DSM 20076. These concentrations all led to marked decreases in both the number of viable cells and in optical density, indicating that the activity of the acidocin D20079 was bactericidal with concomitant cell lysis. Moreover, the probiotic potential of L. acidophilus DSM 20079 was analyzed for its ability to survive and retain viability at conditions (acid and bile concentrations) mimicking the gastrointestinal (GI) tract, under which it survived exposure to pH 2.0 with a 1.2 log cycle reduction in viability and where 45% of the original population survived in a medium containing 0.3% bile for 3 h.  相似文献   
118.
This paper describes the construction, operation and predictive modeling of a molecular machine, functioning as a high sensitivity biosensor. Embedded gramicidin A (gA) ionchannels in a self-assembled tethered lipid bilayer act as biological switches in response to target molecules and provide a signal amplification mechanism that results in high sensitivity molecular detection. The biosensor can be used as a rapid and sensitive point of care diagnostic device in different media such as human serum, plasma and whole blood without the need for pre and post processing steps required in an enzyme-linked immunosorbent assay. The electrical reader of the device provides the added advantage of objective measurement. Novel ideas in the construction of the molecular machine, including fabrication of biochip arrays, and experimental studies of its ability to detect analyte molecules over a wide range of concentrations are presented. Remarkably, despite the complexity of the device, it is shown that the response can be predicted by modeling the analyte fluid flow and surface chemical reactions. The derived predictive models for the sensing dynamics also facilitate determining important variables in the design of a molecular machine such as the ion channel lifetime and diffusion dynamics within the bilayer lipid membrane as well as the bio-molecular interaction rate constants.  相似文献   
119.
Functional genomics requires structural and functional studies of a large number of proteins. While the production of proteins through over-expression in cultured cells is a relatively routine procedure, the subsequent protein purification from the cell lysate often represents a significant challenge. The most direct way of protein purification from a cell lysate is affinity purification using an affinity probe to the target protein. It is extremely difficult to develop antibodies, classical affinity probes, for a protein in the cell lysate; their development requires a pure protein. Thus, isolating the protein from the cell lysate requires antibodies, while developing antibodies requires a pure protein. Here we resolve this loop problem. We introduce AptaPIC, Aptamer-facilitated Protein Isolation from Cells, a technology that integrates (i) the development of aptamers for a protein in cell lysate and (ii) the utilization of the developed aptamers for protein isolation from the cell lysate. Using MutS protein as a target, we demonstrate that this technology is applicable to the target protein being at an expression level as low as 0.8% of the total protein in the lysate. AptaPIC has the potential to considerably speed up the purification of proteins and, thus, accelerate their structural and functional studies.  相似文献   
120.
Herein we report a successful application of a computer-aided design approach to identify a novel HCV helicase inhibitor. A de novo drug design methodology was used to generate an initial set of structures that could potentially bind to a putative binding site. Further structure refinement was carried out through docking a series of focused virtual libraries. The most promising compound was synthesised and it exhibited a submicromolar inhibition of the HCV helicase.  相似文献   
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