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101.
Cystic echinococcosis (CE) caused by Echinococcus granulosus is a major public health problem worldwide, including Turkey. The aim of the current study was to identify the strains and to estimate the potential risk factors of E. granulosus in operated pediatric cases in eastern Turkey. Ten pediatric patients (7 boys and 3 girls) living in rural areas, with ages ranging from 3 to 15 years old and various clinical histories, were included in this study. Eight patients had only liver hydatid cyst, while 1 patient had liver and lung hydatid cyst and the other liver, lung, and spleen, together. There were 2 ruptured liver cysts. After surgery, during follow-up, no increase was observed in hemagglutination levels, there were no mortalities, and there was no evidence of recurrence at 2 years post operation in all patients. Molecular analysis was performed on hydatid cyst samples obtained from the 10 pediatric cases. According to mt-12S rRNA PCR results, all cases were found to be G1/G3 cluster of E. granulosus sensu stricto.  相似文献   
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103.
Abstract Burkholderia cepacia has emerged as an important multiresistant pathogen in cystic fibrosis (CF), associated in 20% of colonised patients with a rapid and fatal decline in lung function. Although knowledge of B. cepacia epidemiology has improved, the mechanisms involved in pathogenesis remain obscure. In this study, B. cepacia lipopolysaccharide (LPS) was assessed for endotoxic potential and the capacity to induce tumour necrosis factor (TNF). LPS preparations from clinical and environmental isolates of B. cepacia and from the closely related species Burkholderia gladioli exhibited a higher endotoxic activity and more pronounced cytokine response in vitro compared to preparations from the major CF pathogen Pseudomonas aeruginosa . This study may help to explain the vicious host immune response observed during pulmonary exacerbations in CF patients colonised by B. cepacia and lead to therapeutic advances in clinical management.  相似文献   
104.
The ovine map is not yet well-developed, which represents a problem when looking for markers of a region of interest in sheep. A means of circumventing this is to use comparative mapping. In this study primers were determined using consensus sequences for the epidermal growth factor gene of humans, rats and mice, and an ovine epidermal growth factor gene fragment was amplified by polymerase chain reaction (PCR). A new set of specific ovine primers was chosen to study the polymorphism of this DNA fragment by denaturing gradient gel electrophoresis. Eighty-four individuals belonging to seven sheep breeds were studied with this technique and four alleles were detected. The heterozygosity rate was 0.57. Family analysis showed mendelian inheritance of the alleles. Usually, genetic analysis of type-I loci used in the comparative mapping is based on the detection of restriction fragment length polymorphisms in sheep DNA using cDNA probes from other species. Our work shows that another method, based on PCR and denaturing gradient gel electrophoresis techniques, can be efficiently used.  相似文献   
105.
Fluoride compounds are known as hazardous environmental pollutants that can enter the body with drinking water. Chronic exposure to fluoride leads to development of oxidative stress and can lead to activation of nuclear factor κB (NF-κB). The aim of this work is to clarify the role of NF-kB activation in production of reactive nitrogen and oxygen species, activity of antioxidant enzymes and intensity of lipid peroxidation (LPO) in gastric mucosa of rats during chronic fluoride intoxication.Materials and methodsWe carried out the study on 18 mature male rats of the Wistar line. The animals were divided into 3 groups: control animals (6), group of chronic fluoride intoxication (6), and animals (6), which received the NF-κB inhibitor, namely ammonium pyrrolidine dithiocarbamate (PDTC) in a dose of 76 mg / kg (iNF-κB group) during modeling of chronic fluoride intoxication. To assess the development of oxidative stress we studied superoxide production (O2-), activity of superoxide dismutase (SOD), catalase (CAT) and concentration of free malondialdehyde (MDA). We also assessed NO production and concentration of its metabolites (peroxynitrite, nitrosilated thiol groups, nitrites).ResultsChronic fluoride intoxication leads to NO hyperproduction with subsequent increase in concentration of its later metabolites (peroxynitrite, nitrosilated thiol groups, nitrites). Production of O2- increases, SOD activity decreases, CAT activity increases and MDA concentration also increases. Inhibition of NF-kB activation by PDTC normalizes the parameters studied.ConclusionsActivation of NF-κB during chronic fluoride intoxication leads to the development of hyperproduction of NO and development of oxidative-nitrosative stress.  相似文献   
106.
《Chirality》2017,29(5):159-166
Here we review our three recently developed analytical models describing the intraband optical activity of semiconductor nanocrystals, which is induced by screw dislocations, ionic impurities, or irregularities of the nanocrystal surface. The models predict that semiconductor nanocrystals can exhibit strong optical activity upon intraband transitions and have large dissymmetry of magnetic‐dipole absorption. The developed models can be used to interpret experimental circular dichroism spectra of nanocrystals and to advance the existing techniques of enantioseparation, biosensing, and chiral chemistry.  相似文献   
107.
Karachi is one of the most populated urban agglomerations in the world. No categorical study has yet discussed the geochemical baseline concentrations of metals in the urban soil of Karachi. The main objectives of this study were to establish geochemical baseline values and to assess the pollution status of different heavy metals. Geochemical baseline concentrations of heavy metals were estimated using the cumulative frequency distribution (CDF) curves. The estimated baseline concentrations of Pb, Cr, Cu, Zn and Fe were 56.23, 12.9, 36.31, 123.03 and 11,776 mg kg−1, respectively. The pollution status of heavy metals in urban soils was evaluated using different quantitative indices (enrichment factor–EF, Geo-accumulation Index–Igeo, and pollution index–PI). Enrichments factors of the selected heavy metals determined by using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. The urban soils of Karachi were found to have a moderate to moderately severe enrichment with Pb, whereas Cr and Cu has moderate and Zn has minor enrichment. Igeo results indicated moderate soil contamination by Pb at some of the sampling locations. PI for Pb, Cr, Cu and Zn was found in the range of 0.04–3.42, 0.19–1.55, 0.27–2.45 and 0.32–1.57, respectively. Large variations in PI values of Pb revealed that soil in those areas of the city which are influenced by intensive anthropogenic activities have exceptionally high concentrations of Pb. The findings of this study would contribute to the environmental database of the soil of the region and would also facilitate both at the local and the international scales, in a more accurate global environmental monitoring, which will eventually facilitate the development of management and remediation strategies for heavy metal contaminated urban soil.  相似文献   
108.
There are conflicting data about the effect of the epidermal growth factor (EGF) on protein kinase C (PKC) enzyme activity. The aim of our study was to find out which type of phospholipids [phosphatidylinositol 4,5-bisphosphate P14,5P2 or the other phospholipids-phosphatidylcholine (PC) or phosphatidic acid (PA)] could be the source of 1,2-diacylglycerol (1,2-DAG) in PKC activation. In colon carcinoma cells (HT29) we observed a more than 2-fold increase in the PC pool and at the same time decreased tyrosine kinase activity (50%). With increasing incubation time EGF affects the pools of both phosphatidylinositols and other phospholipids parallel with the activation of the tyrosine kinase activity. EGF increases the activity of PKC in the HT29 cell line and PC could be the source of 1,2-DAG which may stimulate PKC activity.  相似文献   
109.
Salt-sensitive hypertension is a major risk factor for renal impairment leading to chronic kidney disease. High-salt diet leads to hypertonic skin interstitial volume retention enhancing the activation of the tonicity-responsive enhancer-binding protein (TonEBP) within macrophages leading to vascular endothelial growth factor C (VEGF-C) secretion and NOS3 modulation. This promotes skin lymphangiogenesis and blood pressure regulation. Whether VEGF-C administration enhances renal and skin lymphangiogenesis and attenuates renal damage in salt-sensitive hypertension remains to be elucidated. Hypertension was induced in BALB/c mice by a high-salt diet. VEGF-C was administered subcutaneously to high-salt-treated mice as well as control animals. Analyses of kidney injury, inflammation, fibrosis, and biochemical markers were performed in vivo. VEGF-C reduced plasma inflammatory markers in salt-treated mice. In addition, VEGF-C exhibited a renal anti-inflammatory effect with the induction of macrophage M2 phenotype, followed by reductions in interstitial fibrosis. Antioxidant enzymes within the kidney as well as urinary RNA/DNA damage markers were all revelatory of abolished oxidative stress under VEGF-C. Furthermore, VEGF-C decreased the urinary albumin/creatinine ratio and blood pressure as well as glomerular and tubular damages. These improvements were associated with enhanced TonEBP, NOS3, and lymphangiogenesis within the kidney and skin. Our data show that VEGF-C administration plays a major role in preserving renal histology and reducing blood pressure. VEGF-C might constitute an interesting potential therapeutic target for improving renal remodeling in salt-sensitive hypertension.  相似文献   
110.
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