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121.

Background

Endothelin-1 (ET-1) and Nitric Oxide (NO) are crucial mediators for establishing pulmonary artery hypertension (PAH). We tested the hypothesis that their imbalance might also occur in COPD patients with PAH.

Methods

The aims of the study were to measure exhaled breath condensate (EBC) and circulating levels of ET-1, as well as exhaled NO (FENO) levels by, respectively, a specific enzyme immunoassay kit, and by chemiluminescence analysis in 3 groups of subjects: COPD with PAH (12), COPD only (36), and healthy individuals (15). In order to evaluate pulmonary-artery systolic pressure (PaPs), all COPD patients underwent Echo-Doppler assessment.

Results

Significantly increased exhaled and circulating levels of ET-1 were found in COPD with PAH compared to both COPD (p < 0.0001) only, and healthy controls (p < 0.0001). In COPD with PAH, linear regression analysis showed good correlation between ET-1 in EBC and PaPs (r = 0.621; p = 0.031), and between arterial levels of ET-1 and PaPs (r = 0.648; p = 0.022), while arterial levels of ET-1 inversely correlated with FEV1%, (r = -0.59, p = 0.043), and PaPs negatively correlated to PaO2 (r = -0.618; p = 0.032). Significantly reduced levels of FENO were found in COPD associated with PAH, compared to COPD only (22.92 ± 11.38 vs.35.07 ± 17.53 ppb; p = 0.03). Thus, we observed an imbalanced output in the breath between ET-1 and NO, as expression of pulmonary endothelium and epithelium impairment, in COPD with PAH compared to COPD only. Whether this imbalance is an early cause or result of PAH due to COPD is still unknown and deserves further investigations.  相似文献   
122.

Surface plasmon resonance (SPR), a highly sensitive and label-free optical biosensing technique, is a powerful tool for studying biomolecular interactions. An immunosensor for rapid, sensitive, and selective detection of Vibrio cholerae on the basis of SPR is reported. Recombinant OmpW antigen (a bacterial outer-membrane protein) of V. cholerae was expressed and purified and raising of polyclonal rabbit anti-OmpW was done. Antibodies were immobilized on a sensor surface and interactions between OmpW protein and the whole cell of V. cholerae with immobilized antibodies were studied in different experiments. The aim of this study was to evaluate the potential of anti-OmpW in detection of V. cholerae by developing an immunosensor based on SPR. The results showed high affinity interaction between OmpW and anti-OmpW (K D = 2.4 ± 0.07 × 10−9 M) and SPR signals had a linear relationship with the number of V. cholerae ranging from 1 × 102 to 1 × 107 cells/mL with limit of detection of 50 cells/mL. The specificity of the developed immunoassay was examined using some non-V. cholerae bacteria which did not produce any significant responses. This method is rapid, sensitive, and specific to target V. cholerae with a total analysis time of less than 60 min.

  相似文献   
123.
Helicobacter pylori infection could induce oxidative stress. Oxidative stress is involved in the pathogenesis of gastric diseases. Glutathione peroxidase 1 (GPX1), is part of the enzymatic antioxidant defense, preventing oxidative damage. The aim of the present study was to assess the association of GPX1 Pro198Leu genotypes with gastric cancer in patients with and without H. pylori infection in a population of Northern Iran. The present case-control study consisted of 50 patients with gastric cancer and 78 cancer-free subjects as controls. Extraction of DNA was performed on bioptic samples and the GPX1 genotypes were identified using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The frequencies of GPX1 Pro/Pro, Pro/Leu and Leu/Leu genotypes in controls were 21.8, 71.8 and 6.4%, respectively. However, in gastric cancer patients, the frequencies of 34, 56 and 10% were observed for Pro/Pro, Pro/Leu and Leu/Leu genotypes, respectively (p?=?0.185). In 38 (76%) patients infected with H. pylori, the frequencies of Pro and Leu alleles were 94.7 and 3.3%, respectively. There was a higher frequency of combined genotype of Pro/Leu?+?Leu/Leu (94.7%) in H. pylori positive patients than that in patients without H. pylori infection (75%, p?=?0.047). The presence of this genotype tended to increase the risk of H. pylori related gastric cancer by 5.88–fold (p?=?0.069) in our population. Our findings indicated the absence of association between the GPX1 Pro198Leu polymorphism and the risk of gastric cancer in an Iranian population. However, we detected an association between H. pylori related gastric cancer with GPX1 Pro/Leu?+?Leu/Leu genotype.  相似文献   
124.
Sex determining region Y gene (SRY) is located on Y chromosome and encodes a protein with 229 amino acids. In this study, ORF region of SRY with a length of 690 bp was synthesized using PCR and ligated to pET28a (+), then transformed in E.coli DH5α. E.coli BL21 (DE3) strain was chosen to express recombinant bovine SRY protein. A set of optimization steps was taken including different concentrations of IPTG, glucose, and temperatures at differed incubation times after the induction. Results showed that temperature points and different concentrations of IPTG and glucose had a significant effect (p < 0.01) on total protein and recombinant bovine SRY. After purification, various temperatures and concentrations of IPTG showed meaningful effects (p < 0.01) on the solubility of expressed recombinant SRY. Highest soluble rSRY protein amount was achieved where 0.5 mM IPTG and 0.5% glucose was used at 20°C during induction. In the absence of glucose, the highest amount of soluble recombinant SRY levels were achieved at the concentrations of 0.8 mM of IPTG at 28°C, 20°C, and 1.5 mM IPTG at 37°C during induction for 16, 24, and 8 hours, respectively. Regarding the results obtained in this study, it could be stated that by decreasing temperature and inducer concentration, soluble bovine SRY protein expression increases.  相似文献   
125.
FLK-1/vascular endothelial growth factor receptor 2 (VEGFR-2) is one of the receptors for VEGF. In this study we examined the effect of cell density on activation of VEGFR-2. VEGF induces only very slight tyrosine phosphorylation of VEGFR-2 in confluent (95-100% confluent) pig aortic endothelial (PAE) cells. In contrast, robust VEGF-dependent tyrosine phosphorylation of VEGFR-2 was observed in cells plated in sparse culture conditions (60-65% confluent). A similar cell density-dependent phenomenon was observed in different endothelial cells but not in NIH-3T3 fibroblast cells expressing VEGFR-2. Stimulating cells with high concentrations of VEGF or replacing the extracellular domain of VEGFR-2 with that of the colony-stimulating factor 1 receptor did not alleviate the sensitivity of VEGFR-2 to cell density, indicating that the confluent cells were probably not secreting an antagonist to VEGF. Furthermore, in PAE cells, ectopically introduced platelet-derived growth factor alpha receptor could be activated at both high and low cell density conditions, indicating that the density effect was not universal for all receptor tyrosine kinases expressed in endothelial cells. In addition to lowering the density of cells, removing divalent cations from the medium of confluent cells potentiated VEGFR-2 phosphorylation in response to VEGF. These findings suggested that cell-cell contact may be playing a role in regulating the activation of VEGFR-2. To this end, pretreatment of confluent PAE cells with a neutralizing anti-cadherin-5 antibody potentiated the response of VEGFR-2 to VEGF. Our data demonstrate that endothelial cell density plays a critical role in regulating VEGFR-2 activity, and that the underlying mechanism appears to involve cadherin-5.  相似文献   
126.
Cardiotypic development in embryonic stem cell-derived embryoid bodies may be regulated by reactive oxygen species (ROS). ROS were generated by a NADPH oxidase-like enzyme which was transiently expressed during the time course of embryoid body development. Incubation with either H(2)O(2) or menadione enhanced cardiomyogenesis, whereas the radical scavengers trolox, pyrrolidinedithiocarbamate and N-acetylcysteine exerted inhibitory effects. The phosphatidylinositol 3-kinase (PI-3-kinase) inhibitors LY294002 and wortmannin abolished cardiac commitment and downregulated ROS in embryoid bodies. Coadministration of LY294002 with prooxidants resumed cardiomyocyte differentiation, indicating a role for PI-3-kinase in the regulation of the intracellular redox state.  相似文献   
127.
Beta Thalassemia has been reported to be a common genetic disorder in Iran. To establish the molecular spectrum of the beta thalassemias in the Kermanshah Province of Iran, 185 unrelated beta thalassemia patients with Kurdish ethnic background were studied (181 β-thalassemia major and 4 β-thalassemia intermedia). Using polymerase chain reaction-amplification refractory mutation system (PCR-ARMS), restriction fragment length polymorphism (RFLP) and direct genomic sequencing twenty different mutations were identified accounting for 98.1% of the alleles. Approximately 80.8% of β-thalassemia chromosomes had β0 mutation. The most prevalent mutation was the IVSII-1 (G→A) (32.97%), followed by CD8/9 +G (13.51%), IVSI-110 (C→T) (8.38%), CD 36/37 −T (7.84%), CD8 −AA (5.94%), CD15 (G→A) (4.86%) and IVSI-1 (G→A) (4.59%). All of these mutations accounted for 78.1% of the alleles. The results described here will be of valuable help in the development of successful prevention programs for the population of Kermanshah.  相似文献   
128.
Pharmaceutical molecules such as peptides and proteins are usually injected into the body. Numerous efforts have been made to find new noninvasive ways to administer these peptides. In this study, highly flexible vesicles (transfersomes [TFs]) were designed as a new modern transdermal drug delivery system for systemic drug administration through the skin, which had also been evaluated in vitro. In this study, two growth hormone-loaded TF formulations were prepared, using soybean lecithin and two different surfactants; F1_sodium deoxycholate and F 2_sodium lauryl sulfate. Thereafter, the amount of skin penetration by the two formulas was assessed using the Franz diffusion cell system. TF formulations were evaluated for size, zeta potential and in vitro skin penetration across the rat skin. Results indicated that vesicle formulations were stable for 4 weeks and their mean sizes were 241.33 ± 17 and 171 ± 12.12 nm in the F 1 and F 2 formulation, respectively. After application to rat skin, transport of the human growth hormone (hGH) released from the TF formulations was found to be higher than that of the hGH alone. Maximum amounts of transdermal hormone delivery were estimated to be 489.54 ± 8.301 and 248.46 ± 4.019 ng·cm−2 , for F 1 and F 2, respectively. The results demonstrate the capability of the TF-containing growth hormone in transdermal delivery and superiority of the F 1 to F 2 TFs.  相似文献   
129.
Summary The C3 phenotype distribution was studied in 4 different populations from Afghanistan. The gene frequencies of C3s allele were: Tajiks (0.8547), Pushtoons (0.8812), Hazaras (0.9036) and Osbeks (0.8530). These values were significantly higher than in European populations studied previously. No significant differences were found between the mean serum levels of C3, C4 and C3-proactivator among 4 population groups. A higher concentration of IgG, IgA and IgM was observed in Afghanistan sera than reported for Europeans.Supported by the Stiftung Volkswagenwerk.Dedicated to Prof. J. Kühnau on his 75th birthday.  相似文献   
130.
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