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121.

Objective

To determine whether IL-4, IL-4Rα and STAT6 polymorphisms are associated with susceptibility to dermatitis in Egyptian children.

Methods

We genotyped three groups of children, consisting of 106 atopic dermatitis (AD) children, 95 non-AD children, and 100 of healthy controls, for IL-4 (− 590 C/T), (− 33 C/T), IL-4Rα (I50V), (Q576R) and STAT6 (2964 G/A), (2892 C/T) gene polymorphisms using PCR-RFLP assay. Total serum IgE and serum IL-4 levels were detected by ELISA.

Results

There was a non-significant association of IL-4 − 590 C/T, − 33 C/T polymorphisms in the children with non-AD or those with AD when compared with the controls. We identified a significant association between IL-4Rα I50V, Q576R polymorphisms and dermatitis susceptibility in AD (p = 0.002, < 0.001 respectively), whereas no such association was observed in non-AD group (p = 0.52, 0.99 respectively). A significant association between STAT6 polymorphisms and both types of dermatitis was found. Patients who were carriers of IL4 − 590C, IL-4Rα I50V G, STAT6 2964 A and STAT6 2892 T had an increased risk of AD [OR and 95% CI: 3.2 (2.5–4.2), p = 0.005]. Furthermore, there was no relation between each polymorphism and serum IL-4 level (p > 0.05 for each) while homozygosity for the risk alleles of IL-4, IL-4Rα and STAT6 SNPs were significantly associated with increased total IgE levels in all subjects.

Conclusion

In Egyptian children, the IL-4Rα and the STAT6 polymorphism may play a role in susceptibility to AD. In addition, gene–gene interaction between the IL-4, the IL-4Rα and the STAT6 significantly increases an individual's susceptibility to AD.  相似文献   
122.
Thin filament-associated proteins such as calponin, caldesmon, and smoothelin are believed to regulate acto-myosin interaction and thus, muscle contraction. Oxidative stress has been found to affect the normal contractile behavior of smooth muscle and is involved in the pathogenesis of a number of human diseases such as diabetes mellitus, hypertension, and atherosclerosis. However, very little is known about the effect of oxidative stress on the expression of smooth muscle contractile proteins. The aim of the current study is to investigate the effect of oxidative stress on the expression of thin filament-associated proteins in rat gastric smooth muscle. Single smooth muscle cells of the stomach obtained from Sprague–Dawley rats were used. Muscle cells were treated with hydrogen peroxide (H2O2) (500 μM) for 30 min or the peroxynitrite donor 3-morpholinosydnonimine (SIN-1) (1 mM) for 90 min to induce oxidative stress. Calponin, caldesmon, and smoothelin expressions were measured via specifically designed enzyme-linked immunosorbent assay. We found that exposure to exogenous H2O2 or incubation of dispersed gastric muscle cells with SIN-1 significantly increased the expression of calponin, caldesmon, and smoothelin proteins. In conclusion: oxidative stress increases the expression of thin filament-associated proteins in gastric smooth muscle, suggesting an important role in gastrointestinal motility disorders associated with oxidative stress.  相似文献   
123.
Nimesulide is a COX-2 inhibitor used for symptomatic relief of rheumatoid arthritis. Leflunomide is an anti-pyrimidine used to manage the progression of rheumatoid arthritis. Herein we studied the influence of nimesulide and leflunomide combination in terms of disease symptoms and progression using collagen-induced arthritis model in mice, as a model for rheumatoid arthritis. Collagen induced arthritis was induced by immunization with type II collagen. Assessment of joint stiffness and articular hyperalgesia were evaluated using a locomotor activity cage and the Hargreaves method, respectively. Disease progression was assessed via arthritic index scoring, X-ray imaging, myeloperoxidase enzyme activity and histopathologic examination. Nimesulide induced only transient symptomatic alleviation on the top of decreased leucocytic infiltration compared to arthritis group. However, nimesulide alone failed to induce any significant improvement in the radiological or pathological disease progression. Leflunomide alone moderately alleviates the symptoms of arthritis and moderately retarded the radiological and pathological disease progression. Combination of nimesulide and leflunomide significantly improved symptomatic (analgesia and joint stiffness) and arthritic disease progression (radiological, pathological and Myeloperoxidase enzyme activity) in collagen induced arthritis animal model.  相似文献   
124.
Reduced circulating natriuretic peptide concentrations are independently associated with insulin resistance and type 2 diabetes, while increased natriuretic peptide levels appear to be protective. Observations in vitro and in heart failure patients suggest that atrial natriuretic peptide (ANP) promotes adiponectin release, an adipokine with insulin sensitizing properties. We tested the hypothesis that ANP acutely raises adiponectin levels in 12 healthy men. We infused ANP intravenously over 135 minutes while collecting venous blood and adipose tissue microdialysates at baseline and at the end of ANP-infusion. We obtained blood samples at identical time-points without ANP infusion in 7 age and BMI matched men. With infusion, venous ANP concentrations increased ~10 fold. Systemic and adipose tissue glycerol concentrations increased 70% and 80%, respectively (P<0.01). ANP infusion increased total adiponectin 14±5% and high molecular-weight (HMW)-adiponectin 13±5% (P<0.05). Adiponectin did not change in the control group (P<0.05 vs. infusion). ANP-induced changes in HMW adiponectin and adipose tissue lipolysis were directly correlated with each other, possibly suggesting a common mechanism. Our data show that ANP acutely increases systemic total and HMW-adiponectin concentrations in healthy subjects. Our study could have implications for the physiological regulation of adiponectin and for disease states associated with altered natriuretic peptide availability.  相似文献   
125.

Background

Traditional agro-systems in arid areas are a bulwark for preserving soil stability and fertility, in the sight of “reverse desertification”. Nevertheless, the impact of desert farming practices on the diversity and abundance of the plant associated microbiome is poorly characterized, including its functional role in supporting plant development under drought stress.

Methodology/Principal Findings

We assessed the structure of the microbiome associated to the drought-sensitive pepper plant (Capsicum annuum L.) cultivated in a traditional Egyptian farm, focusing on microbe contribution to a crucial ecosystem service, i.e. plant growth under water deficit. The root system was dissected by sampling root/soil with a different degree of association to the plant: the endosphere, the rhizosphere and the root surrounding soil that were compared to the uncultivated soil. Bacterial community structure and diversity, determined by using Denaturing Gradient Gel Electrophoresis, differed according to the microhabitat, indicating a selective pressure determined by the plant activity. Similarly, culturable bacteria genera showed different distribution in the three root system fractions. Bacillus spp. (68% of the isolates) were mainly recovered from the endosphere, while rhizosphere and the root surrounding soil fractions were dominated by Klebsiella spp. (61% and 44% respectively). Most of the isolates (95%) presented in vitro multiple plant growth promoting (PGP) activities and stress resistance capabilities, but their distribution was different among the root system fractions analyzed, with enhanced abilities for Bacillus and the rhizobacteria strains. We show that the C. annuum rhizosphere under desert farming enriched populations of PGP bacteria capable of enhancing plant photosynthetic activity and biomass synthesis (up to 40%) under drought stress.

Conclusions/Significance

Crop cultivation provides critical ecosystem services in arid lands with the plant root system acting as a “resource island” able to attract and select microbial communities endowed with multiple PGP traits that sustain plant development under water limiting conditions.  相似文献   
126.

Objective

Assessing the feasibility and efficiency of interventions using ultrasound (US) volume navigation (V Nav) with real time needle tracking and image fusion with contrast enhanced (ce) CT, MRI or US.

Methods

First an in vitro study on a liver phantom with CT data image fusion was performed, involving the puncture of a 10 mm lesion in a depth of 5 cm performed by 15 examiners with US guided freehand technique vs. V Nav for the purpose of time optimization. Then 23 patients underwent ultrasound-navigated biopsies or interventions using V Nav image fusion of live ultrasound with ceCT, ceMRI or CEUS, which were acquired before the intervention. A CEUS data set was acquired in all patients. Image fusion was established for CEUS and CT or CEUS and MRI using anatomical landmarks in the area of the targeted lesion. The definition of a virtual biopsy line with navigational axes targeting the lesion was achieved by the usage of sterile trocar with a magnetic sensor embedded in its distal tip employing a dedicated navigation software for real time needle tracking.

Results

The in vitro study showed significantly less time needed for the simulated interventions in all examiners when V Nav was used (p<0.05). In the study involving patients, in all 10 biopsies of suspect lesions of the liver a histological confirmation was achieved. We also used V Nav for a breast biopsy (intraductal carcinoma), for a biopsy of the abdominal wall (metastasis of ovarial carcinoma) and for radiofrequency ablations (4 ablations). In 8 cases of inflammatory abdominal lesions 9 percutaneous drainages were successfully inserted.

Conclusion

Percutaneous biopsies and drainages, even of small lesions involving complex access pathways, can be accomplished with a high success rate by using 3D real time image fusion together with real time needle tracking.  相似文献   
127.
Recent studies suggest that bone marrow stem cells (BMSCs) are promising grafts to treat a variety of diseases, including reproductive dysfunction. Primary ovarian failure is characterized by amenorrhea and infertility in a normal karyotype female, with an elevated serum level of follicle-stimulating hormone (FSH) and a decrease level of estrogen caused by a mutation in FSH receptor (FSHR) gene. Currently, there is no effective treatment for this condition. The phenotype of FSHR (-/-) mouse, FORKO (follitropin receptor knockout), is a suitable model to study ovarian failure in humans. Female FORKO mice have elevated FSH, decreased estrogen levels, are sterile because of the absence of folliculogenesis, and display thin uteri and small nonfunctional ovaries. In this study, we determined the effects of BMSC transplantation on reproductive physiology in this animal model. Twenty four hours post BMSC transplantation, treated animals showed detectable estroidogeneic changes in daily vaginal smear. Significant increase in total body weight and reproductive organs was observed in treated animals. Hemotoxylin and eosin (H&E) evaluation of the ovaries demonstrated significant increase in both the maturation and the total number of the follicles in treated animals. The FSH dropped to 40-50% and estrogen increased 4-5.5 times in the serum of treated animals compared to controls. The FSHR mRNA was detected in the ovaries of treated animals. Our results show that intravenously injected BMSCs were able to reach the ovaries of FORKO mice, differentiate and express FHSR gene, make FSHR responsive to FSH, resume estrogen hormone production, and restore folliculogenesis.  相似文献   
128.
129.

Background/Aim

Kinesin family member 1B (KIF1B) gene resides in the chromosomal region 1p36.22 and has been reported to have frequent deletions in a variety of human cancers. A recent genome wide association study (GWAS) study conducted on a Chinese population has reported the involvement of a KIF1B genetic variant in Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). This study aims to investigate the significance of KIF1B genetic variations in HBV-associated hepatitis in patients of Saudi Arabian ethnicity.

Methods

TaqMan genotyping assay was used to investigate the association of three SNPs (rs17401966, rs12734551, and rs3748578) in 584 normal healthy controls and 660 HBV-infected patients. The patients were categorized into inactive carriers (Case I), active carriers (Case II), Cirrhosis (Case III) and Cirrhosis-HCC (Case IV) sub-groups.

Results

Since SNPs rs12734551 and rs3748578 are in strong linkage disequilibrium (LD) with rs17401966, only results for the latter SNP are reported. Therefore, the allele frequency of rs17401966 among HBV-infected patients and healthy controls were comparable and therefore, no significant association was observed (P = 0.2811, Odds Ratio (OR) 0.897). A similar analysis was performed among the different sub-groups in order to determine whether KIF1B SNPs were associated with the advancement of the disease. No significant differences were observed in any of the comparisons performed.

Conclusion

Polymorphisms at KIF1B gene locus investigated in this study showed no significant association with HBV infection or with HBV-associated diseases such as liver cirrhosis or HCC.  相似文献   
130.
Background aimsDelayed neutrophil recovery following autologous hematopoietic stem cell transplantation (aHSCT) increases transplant-related morbidity. Apoptosis induced by cryopreservation and thawing of hematopoietic progenitor cells collected by apheresis (HPC-A) was investigated in this nested case-control study as a factor associated with delayed neutrophil recovery following aHSCT.MethodsAmong patients with lymphoma who underwent aHSCT between 2000 and 2007 (n = 326), 13 cases of primary delayed neutrophil recovery and 22 age- and sex-matched controls were identified. Apoptosis and viability were measured using multiparameter flow cytometry, and colony-forming capacity was determined using semi-solid methylcellulose assays.ResultsHPC-A grafts from cases and controls had similar percentages of viable mononuclear cells (MNC) and CD34+progenitor cells, as determined by standard 7AAD dye exclusion methods measured before and after cryopreservation. Patients with delayed neutrophil recovery received increased numbers of apoptotic MNC (P = 0.02) but similar numbers of apoptotic CD34+ cells per kilogram measured after thawing. Apoptosis was more pronounced in MNC compared with CD34+ cells after thawing, and apoptosis was negligible in freshly collected HPC-A products. Patients with delayed neutrophil recovery had fewer total colony-forming unites (CFU) and CFU-granulocyte–macrophages (GM) per 105 viable post-thaw MNC compared with controls (P < 0.05).ConclusionsIncreased numbers of apoptotic MNC in thawed HPC-A products are associated with delayed neutrophil recovery after aHSCT. Studies that address factors contributing to increased apoptosis are needed, and measuring apoptosis in thawed HPC-A may have a role in the assessment of graft adequacy.  相似文献   
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