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Daneshmandi S Pourfathollah AA Pourpak Z Heidarnazhad H Kalvanagh PA 《Molecular biology reports》2012,39(2):1845-1853
Asthma is a multifactor inflammatory disorder, and its management requires understanding of its various pathogenesis and control
mechanisms. Cytokines and other inflammatory mediators are important factors in asthma pathophysiology. In this study, we
evaluated the role of cytokine polymorphisms in the asthma susceptibility, progress, control, and lung functions. IL-4-C590T
polymorphism by PCR-RFLP method, IFN-γ T+874A, TNF-α-A308G, IL-6 G−174C and TGF-β T+869C variants by ARMS-PCR method and IgE
serum level by ELISA technique were determined in 81 asthmatic patients and 124 normal subjects. Asthma diagnosis, treatment
and control levels were considered using standard schemes and criteria. TNF-α−308GA genotype was more frequent in asthmatics
(P = 0.025, OR 3.352), and polymorphisms between different asthma control levels (P > 0.05) were not different. IFN-γ+874AT genotype had a positive correlation with the familial history of asthma (P = 0.034, OR 2.688). IL-6−174C allele (P = 0.045), TNF-α−308GG genotype (P = 0.002) and TNF-α−308G allele (P = 0.004) showed reduced values, and TNF-α−308GA genotype (P = 0.002) increased FEF25-75 value in asthmatics. IFN-γ+874AA genotype caused a decrease in FVC factor (P = 0.045). This study showed that TNF-α−308GA is a risk factor for asthma, but cytokine gene variants do not affect asthma
control and IgE serum levels. Variants producing lower levels of IL-6, TNF-α and IFN-γ are associated with reduced pulmonary
capacities. To achieve an appropriate schema for asthma management, further studies with consideration of different aspects
in a larger group of patients would be more elucidative. 相似文献
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The couplons of the cardiomyocyte form nanospaces within the cell that place the L-type calcium channel (Cav1.2), situated on the plasmalemma, in opposition to the type 2 ryanodine receptor (RyR2), situated on the sarcoplasmic reticulum. These two molecules, which form the basis of excitation–contraction coupling, are separated by a very limited space, which allows a few Ca2+ ions passing through Cav1.2 to activate the RyR2 at concentration levels that would be deleterious to the whole cell. The limited space also allows Ca2+ inactivation of Cav1.2. We have found that not all couplons are the same and that their properties are likely determined by their molecular partners which, in turn, determine their excitability. In particular, there are a class of couplons that lie outside the RyR2-Cav1.2 dyad; in this case, the RyR2 is close to caveolin-3 rather than Cav1.2. These extra-dyadic couplons are probably controlled by the multitude of molecules associated with caveolin-3 and may modulate contractile force under situations such as stress. It has long been assumed that like the skeletal muscle, the RyR2 in the couplon are arranged in a structured array with the RyR2 interacting with each other via domain 6 of the RyR2 molecule. This arrangement was thought to provide local control of RyR2 excitability. Using 3D electron tomography of the couplon, we show that the RyR2 in the couplon do not form an ordered pattern, but are scattered throughout it. Relatively few are in a checkerboard pattern—many RyR2 sit edge-to-edge, a configuration which might preclude their controlling each other's excitability. The discovery of this structure makes many models of cardiac couplon function moot and is a current avenue of further research 相似文献
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The interaction between the synaptic adhesion molecules neuroligins and neurexins is essential for connecting the pre- and post-synaptic neurons, modulating neuronal signal transmission, and facilitating neuronal axogenesis. Here, we describe the simultaneous expression of the extracellular domain of rat neuroligin-1 (NL1) proteins along with the enhanced green fluorescent protein (EGFP) using the bi-cistronic baculovirus expression vector system (bi-BEVS). Recombinant rat NL1 protein, fused with signal sequence derived from human Azurocidin gene (AzSP), was secreted into the culture medium and the optimum harvest time for NL1 protein before the lysis of infected cells was determined through the release of cytosolic EGFP. The NL1 protein (0.129±0.013 mg/8×10(7) High Five cells; ~96% purity by metal affinity chromatography) was obtained from the supernatant of the recombinant virus-infected insect cells. A novel chip was employed to address whether the recombinant NL1 is functional in axogenesis. The purified rat NL1 promoted and enhanced the growth rate (137.07±9.74 μm/day) of the axon on NL1/PLL (poly-L-lysine)-coated fine lines on the chip compared to those lines that were coated with PLL alone (105.53±4.53 μm/day). These results were confirmed by fluorescence immunocytochemistry and demonstrated that the recombinant protein can be purified by a one-step process using IMAC combined with monitoring of cell lysis by bi-BEVS. This technique along with our novel chip offers a simple, cost-effective and useful platform for understanding the roles of NL1 protein in neuronal regeneration and synaptic formation studies. 相似文献
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Zahra Yazdani Alireza Rafiei Monireh Golpour Parisa Zafari Mohammadreza Moonesi Sasan Ghaffari 《Journal of cellular biochemistry》2020,121(3):2064-2076
Interleukin 35 (IL-35), a cytokine mainly produced by regulatory T cells (Treg cells), is composed of an Epstein-Barr virus–induced gene 3 β-chain and an IL-12 p35 α-chain. IL-35 causes tumorigenicity in cancer, protects cancer cells against apoptosis, and facilitates cancer progression. However, a few reports have referred to its contradictory roles in cancer prevention. Therefore, the exact purpose of this cytokine in cancer development has become a fundamental question that needs to be answered. In this review, we explain the structure of IL-35 and its receptors and their different signaling pathways. Finally, the function of IL-35 in some cancers and the possible application of this cytokine in approaches for cancer therapy have been discussed. 相似文献
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Effect of circular permutation on the structure and function of type 1 blue copper center in azurin 下载免费PDF全文
Yang Yu Igor D. Petrik Kelly N. Chacón Parisa Hosseinzadeh Honghui Chen Ninian J. Blackburn Yi Lu 《Protein science : a publication of the Protein Society》2017,26(2):218-226
Type 1 copper (T1Cu) proteins are electron transfer (ET) proteins involved in many important biological processes. While the effects of changing primary and secondary coordination spheres in the T1Cu ET function have been extensively studied, few report has explored the effect of the overall protein structural perturbation on active site configuration or reduction potential of the protein, even though the protein scaffold has been proposed to play a critical role in enforcing the entatic or “rack‐induced” state for ET functions. We herein report circular permutation of azurin by linking the N‐ and C‐termini and creating new termini in the loops between 1st and 2nd β strands or between 3rd and 4th β strands. Characterization by electronic absorption, electron paramagnetic spectroscopies, as well as crystallography and cyclic voltammetry revealed that, while the overall structure and the primary coordination sphere of the circular permutated azurins remain the same as those of native azurin, their reduction potentials increased by 18 and 124 mV over that of WTAz. Such increases in reduction potentials can be attributed to subtle differences in the hydrogen‐bonding network in secondary coordination sphere around the T1Cu center. 相似文献
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The problem of deterioration of art works is particularly relevant in countries like Iran that are rich in cultural heritage.
According to UNESCO data, Iran holds the tenth rank in a list of countries possessing the highest number of monuments belonging
to the world cultural heritage. Archaeological areas, buildings, mosques, statues, museums and objects are all exposed to
different biogenic and abiogenic stresses under generally aggressive climatic conditions. Lichens and fungi are known to actively
decompose stone surfaces. This process is both physical and chemical in nature and often reaches deep below the stone surfaces.
This is caused by chemical and physical interactions of the microbiota with the fluctuating and often drastically changing
environmental conditions. Here, we describe and analyze the mainly physical degradation by invading fungal hyphae between
stone crystals and a generally destabilizing stone texture. In addition to physical deterioration, organic acids produced
by lichens enhance the chemical decomposing processes. In this work, penetration of hyphal bundles as well as individual fungi
was studied, and the biodeteriorating patterns were documented and compared to general physical–chemical weathering phenomena.
Several strains of aggressive black yeast-like fungi and bacteria were isolated and cultivated and will be described in a
taxonomical context with many other isolates from different localities using physiological, morphological and molecular data. 相似文献