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81.
Studies about the role of cytokines on the immunopathogenesis of atopic dermatitis (AD) are generally based on in vitro observations and this role has not been completely clarified yet. Serum levels of total IgE, IL-18, IL-12, IFN-gamma and the relationship between these parameters and disease severity, determined using the SCORAD index, in a group of atopic patients were investigated in this study. Serum levels of total IgE were measured by the nephelometric method and serum levels of IL-18, IL-12/p40 and IFN-gamma were measured by ELISA method. Serum levels of total IgE and IL-18 were found significantly higher in study group than in controls (P<.001). There was no statistically significant difference between patients and controls in respect of serum levels of IL-12/p40 (P = .227). A statistically significant relationship between SCORAD values and serum levels of total IgE (P < .001), IL-18 (P < .001), and IL-12/p40 (P < .001) was determined. These results show that serum levels of IL-18 can be a sensitive parameter that importantly correlates with clinical severity of AD, can play a role in the immunopathogenesis of AD, and furthermore may be used in the diagnosis and follow-up of the disease in addition to other parameters.  相似文献   
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Stereotaxic surgery has been an invaluable tool in systems neuroscience, applied in many experiments for the creation of site-targeted lesions, injection of anatomical tracers or implantation of electrodes or microdialysis probes. In this protocol, we describe stereotaxic surgery optimized for gene delivery by recombinant adeno-associated viruses and lentiviruses in mice and rats. This method allows the manipulation of gene expression in the rodent brain with excellent spatiotemporal control; essentially any brain region of choice can be targeted and cells (or a subpopulation of cells) in that region can be stably genetically altered at any postnatal developmental stage up to adulthood. Many aspects of the method, its versatility, ease of application and high reproducibility, make it an attractive approach for studying genetic, cellular and circuit functions in the brain. The entire protocol can be completed in 1-2 hours.  相似文献   
84.
The phylum Placozoa is represented by a single known species, Trichoplax adhaerens, a tiny marine organism that represents the most simple metazoan bauplan. Because of the latter, placozoans were originally considered the most basal metazoan phylum. A misinterpretation of the life cycle at the turn of the century and some more recent molecular phylogenetic analyses have placed Trichoplax as a derived species within the Cnidaria. The latter hypothesis assumes that the primitive organization of the Placozoa is the result of secondary reduction. Here we compare the molecular morphology of the predicted 16S rDNA structure and the mitochondrial genome between Trichoplax and representatives of all four cnidarian classes. Trichoplax shares a circular mtDNA molecule as a plesiomorphy with all other metazoans except for the derived cnidarian classes Hydrozoa, Scyphozoa, and Cubozoa. The predicted secondary structure of the 16S rRNA molecule differs substantially between Trichoplax and cnidarians, particularly with respect to the number and length of stem and loop regions. The new molecular morphological characters provide compelling evidence that Trichoplax is not a derived (medusozoan) cnidarian. Furthermore, it was found that the mitochondrial genome in Cubozoa consists of four linear molecules instead of a single circular molecule or two linear molecules, suggesting that the cubozoans may represent the most derived cnidarian group.  相似文献   
85.
7,12-Dimethylbenz[a]anthracene (7,12-DMBA) is a member of the polycyclic aromatic hydrocarbons with a severe carcinogenic effect. In this study, nitrate levels and ADA (Adenosine deaminase) activity in the liver homogenates of mice were measured and the effect of free radicals induced by 7,12-DMBA on inducible nitric oxide synthase (iNOS) and ADA activity were investigated. Antioxidant effects of melatonin were also compared. Three groups of mice were included in the study. The first served as control, the second was treated only with 7,12-DMBA and the third was treated with 7,12-DMBA + melatonin. Spectrophotometric methods were used at all measurements. Data were analyzed using Kruskal-Wallis Variance Analysis Test and Mann-Whitney U Test that were applied to the groups. The nitrate concentrations of mouse liver were as follows: 4.98 +/- 0.63 micro mol/L in the control group (n = 10), 8.23 +/- 1.58 micro mol/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group (n = 10), and 6.43 +/- 0.57 micro mol/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA + melatonin-treated group (n = 10). Liver ADA activities were measured to be 4.14 +/- 0.674 U/L in the control group, 6.25 +/- 1.261 U/L (higher than control group, p < 0.05) in the 7,12-DMBA-treated group, and 4.93 +/- 0.916 U/L (lower than 7,12-DMBA-treated group, p < 0.05) in the 7,12-DMBA+melatonin-treated group. Differences between free nitrite levels were no significantly. Results demonstrated that nitrate levels and ADA activities were increased by means of free radicals induced by 7,12-DMBA. Melatonin inhibited the 7,12-DMBA induced increase that was observed in the activities of ADA enzyme and nitrate levels. It is concluded that determination of ADA activity and nitrate levels can be useful in the assessment of liver damage caused by toxic chemicals.  相似文献   
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BACKGROUND/AIMS: Insulin resistance is associated with serum C-reactive protein (CRP) levels. We aimed to evaluate the effect of bicalutamide on insulin resistance and serum CRP levels in non-obese polycystic ovarian syndrome (PCOS) patients. METHODS: 40 non-obese patients (BMI < or =25 kg/m2) with PCOS and, 40 age- and BMI-matched healthy women were studied. Patients received bicalutamide orally at the dose of 25 mg/day. Serum CRP levels were measured with immunometric assay. Homeostasis model assessment (HOMA-IR) index was used for insulin resistance. RESULTS: Mean Ferriman-Gallwey score (FGS) (p = 0.001), insulin (p = 0.001), serum glucose (p = 0.001), prolactin (p < 0.003), total (p < 0.04) and free testosterone (p = 0.001) and free androgen index (FAI) levels (p = 0.001) of PCOS subjects were higher than in the control group. Mean HOMA-IR of PCOS patients was higher than in control subjects (2.43 +/- 1.2 and 0.94 +/- 0.37, p = 0.001). CRP levels in subjects with PCOS was also higher than in control subjects (4.27 +/- 1.33 and 0.98 +/- 0.19, p = 0.001). After bicalutamide treatment, FGS, free and total testosterone and FAI decreased (p = 0.001). HOMA-IR, prolactin and CRP levels did not show any statistical difference with bicalutamide treatment. CONCLUSIONS: PCOS patients had insulin resistance and a high CRP level. Bicalutamide treatment did not influence insulin resistance and CRP level in PCOS, and this ineffectiveness of bicalutamide on CRP levels may be the result of insulin resistance and/or high prolactin levels at this time.  相似文献   
88.
Insulin resistance (IR) and obesity may be risk factors for breast cancer. The mechanism of IR in patients with cancer has not been fully clarified yet. This study was conducted to evaluate the possible role of circulating cytokines; tumor necrosis factor-alpha (TNF-alpha) and interleukin 6 (IL-6) in inducing IR in 20 overweight or obese patients with early stage breast cancer and to compare their levels with that of body mass index matched 20 healthy controls. IR was calculated by homeostasis model assessment (HOMA) method. Four groups were formed according to a 2.7 HOMA-IR cut-off value as breast cancer with or without IR and controls with or without IR. IL-6 and HOMA-IR values were found to be higher in breast cancer patients with IR compared to other groups. There was no significant difference in TNF-alpha levels between groups. HOMA-IR values correlated with estradiol and IL-6 levels in all breast cancer patients but not TNF-alpha. HOMA-IR values, serum insulin, estradiol and IL-6 levels in the receptor positive group were significantly higher than those of the receptor negative group. These results suggested a possible contribution of endogenous IL-6 production and hyperinsulinemia to the development of breast cancer in overweight or obese patients with prominent IR.  相似文献   
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90.

Background  

Abdominal aortic aneurysm (AAA) is a prevalent disease which is of significant concern because of the morbidity associated with the continuing expansion of the abdominal aorta and its ultimate rupture. The transient interaction between blood flow and the wall contributes to wall stress which, if it exceeds the failure strength of the dilated arterial wall, will lead to aneurysm rupture. Utilizing a computational approach, the biomechanical environment of virtual AAAs can be evaluated to study the affects of asymmetry and wall thickness on this stress, two parameters that contribute to increased risk of aneurysm rupture.  相似文献   
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