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31.
Bugdaci MS Zuhur SS Sokmen M Toksoy B Bayraktar B Albayrak B Altuntas Y 《Helicobacter》2011,16(2):124-130
Background: Helicobacter pylori infection is a most frequent cause of chronic gastritis. H. pylori may decrease absorption of oral thyroxine by decreasing gastric acid secretion in the stomach. In this study, we aimed to investigate the change in thyroid function tests of the cases after H. pylori eradication who were not responding to high doses of thyroxine treatment before H. pylori eradication. Methods: Hypothyroid cases who were not responding to high doses of thyroxine among the ones presented to Endocrinology and Gastroenterohepatology Clinics of Sisli Etfal Training and Research Hospital between 2009 and 2010 were included in the study. Thyroid function tests were performed two times in all cases before and after H. pylori eradication. Duodenal, antral and corporal biopsies, and jejunal aspirates and biopsies were taken during upper gastrointestinal system endoscopies performed in all patients. Cases without intestinal pathology were included in the study. Results: Serum thyrotropin (TSH), free T3, and free T4 values before H. pylori eradication were 30.5 ± 28.8 IU/mL, 2.64 ± 0.56 pg/mL, and 0.92 ± 0.32 ng/mL, respectively, and after eradication were found to be 4.2 ± 10.6 IU/mL, 3.02 ± 0.61 pg/mL, and 1.3 ± 0.34 ng/mL, respectively (p values <.001, .002, and <.001, respectively). After H. pylori eradication treatment, TSH decreased in all of the cases, factitious thyrotoxicosis developed in % 21 of these cases. Conclusion: In hypothyroid cases, H. pylori gastritis may be responsible for an inadequate response to the treatment. H. pylori eradication in the cases receiving high doses of thyroxine has a risk for thyrotoxicosis. 相似文献
32.
The bovine filarial worm Setaria cervi was found to have abundance of glutathione synthetase (GS; EC 6.3.2.3) activity, the enzyme being involved in catalysing the final step of glutathione (GSH) biosynthesis. A RP-HPLC method involving precolumn derivatization with o-phthalaldehyde has been followed for the estimation of GS activity in crude filarial preparations. Subcellular fractionation of the enzyme was undertaken and it was confirmed to be a soluble protein residing mainly in cytosolic fraction. Attempts to determine the Km value for L-gamma-glutamyl-L-cysteine gave a distinctly nonlinear double-reciprocal plot in which data obtained at relatively high dipeptide concentrations (>1 mM) extrapolate to a Km value of about 400 microM whereas data obtained at lower concentrations (<0.1 mM) extrapolate to a value of about 33 microM. Km was determined to be around 950 and 410 microM for ATP and glycine, respectively. The effect of various amino acids was studied on enzyme activity at 1mM concentration. L-cystine caused a significant enzyme inhibition of 11%. Preincubation with N-ethylmaleimide also resulted in significant inhibition of GS activity. 相似文献
33.
Mass media content likely influences the decision of women to breastfeed their newborn children. Relatively few studies have empirically assessed such a hypothesis to date, however. Most work has tended to focus either on specific interventions or on broad general commentary about the role of media. In this study, we examined infant feeding advertisements in 87 issues of Parents' Magazine, a popular parenting magazine, from the years 1971 through 1999. We then used content analysis results to predict subsequent changes in levels of breastfeeding among U.S. women. When the frequency of hand feeding advertisements increased, the percentage change in breastfeeding rates reported the next year generally tended to decrease. These results underscore the need to acknowledge the potential role of popular media content in understanding breastfeeding patterns and public health trends. 相似文献
34.
Shuxian Jiang Radoslaw Zagozdzon Meritxell Alberich Jorda Kalindi Parmar Yigong Fu John S. Williams Jodi Anne T. Wood Alexandros Makriyannis Naheed Banu Shalom Avraham Jerome E. Groopman Hava Karsenty Avraham 《The Journal of biological chemistry》2010,285(46):35471-35478
Endocannabinoids are lipid signaling molecules that act via G-coupled receptors, CB1 and CB2. The endocannabinoid system is capable of activation of distinct signaling pathways on demand in response to pathogenic events or stimuli, hereby enhancing cell survival and promoting tissue repair. However, the role of endocannabinoids in hematopoietic stem and progenitor cells (HSPCs) and their interaction with hematopoietic stem cells (HSC) niches is not known. HSPCs are maintained in the quiescent state in bone marrow (BM) niches by intrinsic and extrinsic signaling. We report that HSPCs express the CB1 receptors and that BM stromal cells secrete endocannabinoids, anandamide (AEA) (35 pg/107 cells), and 2-AG (75.2 ng/107 cells). In response to the endotoxin lipopolysaccharide (LPS), elevated levels of AEA (75.6 pg/107 cells) and 2-AG (98.8 ng/107 cells) were secreted from BM stromal cells, resulting in migration and trafficking of HSPCs from the BM niches to the peripheral blood. Furthermore, administration of exogenous cannabinoid CB1 agonists in vivo induced chemotaxis, migration, and mobilization of human and murine HSPCs. Cannabinoid receptor knock-out mice Cnr1−/− showed a decrease in side population (SP) cells, whereas fatty acid amide hydrolase (FAAH)−/− mice, which have elevated levels of AEA, yielded increased colony formation as compared with WT mice. In addition, G-CSF-induced mobilization in vivo was modulated by endocannabinoids and was inhibited by specific cannabinoid antagonists as well as impaired in cannabinoid receptor knock-out mice Cnr1−/−, as compared with WT mice. Thus, we propose a novel function of the endocannabinoid system, as a regulator of HSPC interactions with their BM niches, where endocannabinoids are expressed in HSC niches and under stress conditions, endocannabinoid expression levels are enhanced to induce HSPC migration for proper hematopoiesis. 相似文献
35.
The aim of this study was to evaluate the correlation between frequency and phospholipase activity of Candida species and denture stomatitis according to Newton’s classification. Seventy-five complete denture wearers were evaluated
for the presence of yeasts on the palatal mucosa by culture method. In addition, the number of yeast isolates producing phospholipase
and amount of this enzyme were determined using egg yolk agar plate method. According to Newton’s classification, 25 denture
wearers were with healthy palatal mucosa while 50 were with any types of denture stomatitis. The frequency of yeasts was linked
to whether subjects had Type II or Type III, but not Type I denture stomatitis. Candida albicans was the most frequently isolated species in denture wearers with and without clinical signs of denture stomatitis and it
was the only species produced phospholipase. Although the amount of phospholipase produced by the C. albicans isolates from denture wearers in control and Type II and III DS groups was not significantly different, there was statistically
significant difference in the number of C. albicans isolates producing phospholipase between patients with and without clinical signs of DS. 相似文献
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39.
Bhattacharya A Chandrasekar B Rahman MM Banu J Kang JX Fernandes G 《Biochemical and biophysical research communications》2006,349(3):925-930
Both n-3 fatty acids (n-3 FA) and calorie-restriction (CR) exert anti-inflammatory effects in animal models of autoimmunity and inflammation. In the present study we investigated the synergistic anti-inflammatory effects of n-3 FA and CR on LPS-mediated inflammatory responses using fat-1 transgenic mice that generate n-3 FA endogenously. Wild-type (WT) and fat-1 mice were maintained on ad libitum (AL) or CR (40% less than AL) diet for 5 mo; splenocytes were cultured in vitro with/without LPS. Our results show: (i) no difference in body weights between WT and fat-1 mice on AL or CR diets, (ii) lower n-6/n-3 FA ratio in splenocytes from fat-1 mice on both AL and CR diets, (iii) significant reduction in NF-kappaB (p65/p50) and AP-1 (c-Fos/c-Jun) DNA-binding activities in splenocytes from fat-1/CR mice following LPS treatment, and (iv) significant reduction in kappaB- and AP-1-responsive IL-6 and TNF-alpha secretion following LPS treatment in splenocytes from fat-1/CR mice. The inhibition of LPS-mediated effects was more pronounced in fat-1/CR mice when compared to fat-1/AL or WT/CR mice. These data show that transgenic expression of fat-1 results in decreased pro-inflammatory n-6 FA, and demonstrate for the first time that splenocytes from fat-1 mice on CR diet exhibit reduced pro-inflammatory response when challenged with LPS. These results suggest that n-3 lipids with moderate CR may confer protection in autoimmune and inflammatory diseases. 相似文献
40.
Hnilova M Karaca BT Park J Jia C Wilson BR Sarikaya M Tamerler C 《Biotechnology and bioengineering》2012,109(5):1120-1130
Development of versatile and flexible assembly systems for fabrication of functional hybrid nanomaterials with well-defined hierarchical and spatial organization is of a significant importance in practical nanobiotechnology applications. Here we demonstrate a bio-enabled self-assembly technique for fabrication of multi-layered protein and nanometallic assemblies utilizing a modular gold-binding (AuBP1) fusion tag. To accomplish the bottom-up assembly we first genetically fused the AuBP1 peptide sequence to the C'-terminus of maltose-binding protein (MBP) using two different linkers to produce MBP-AuBP1 hetero-functional constructs. Using various spectroscopic techniques, surface plasmon resonance (SPR) and localized surface plasmon resonance (LSPR), we verified the exceptional binding and self-assembly characteristics of AuBP1 peptide. The AuBP1 peptide tag can direct the organization of recombinant MBP protein on various gold surfaces through an efficient control of the organic-inorganic interface at the molecular level. Furthermore using a combination of soft-lithography, self-assembly techniques and advanced AuBP1 peptide tag technology, we produced spatially and hierarchically controlled protein multi-layered assemblies on gold nanoparticle arrays with high molecular packing density and pattering efficiency in simple, reproducible steps. This model system offers layer-by-layer assembly capability based on specific AuBP1 peptide tag and constitutes novel biological routes for biofabrication of various protein arrays, plasmon-active nanometallic assemblies and devices with controlled organization, packing density and architecture. 相似文献