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11.
The glyoxalase system and its main enzyme, glyoxalase 1 (GLO1), protect cells from advanced glycation end products (AGEs), such as methylglyoxal (MG) and other reactive dicarbonyls, the formation of which is increased in diabetes patients as a result of excessive glycolysis. MG is partly responsible for harmful protein alterations in living cells, notably in neurons, leading to their dysfunction, and recent studies have shown a negative correlation between GLO1 expression and tissue damage. Neuronal dysfunction is a common diabetes complication due to elevated blood sugar levels, leading to high levels of AGEs. The aim of our study was to determine whether single nucleotide polymorphisms (SNPs) in the GLO1 gene influence activity of the enzyme. In total, 125 healthy controls, 101 type 1 diabetes, and 100 type 2 diabetes patients were genotyped for three common SNPs, rs2736654 (A111E), rs1130534 (G124G), and rs1049346 (5′-UTR), in GLO1. GLO1 activity was determined in whole blood lysates for all participants of the study.  相似文献   
12.
Until recently Dickeya was regarded as a pathogen not established in Finland. As a result the blackleg symptom observed on potato was often associated with Pectobacterium atrosepticum. The occurrence of Dickeya spp. on potato in Finland was first reported in 2004. Since then the prevalence of Dickeya has been monitored through surveys and routine test of seed lots produced in the country. The results of monitoring of Dickeya spp. in seed lots produced in Finland between the years 2004 and 2008 indicated a steady increase in the incidence of Dickeya spp. The highest incidence was observed in samples from the 2006 growing season where about 37% were positive for Dickeya spp. The summer in 2006 was one of the warmest summers recorded in 100 years in Finland. The majority of infected lots were imported varieties. Since recently heavy blackleg outbreaks have occurred in production fields in the High Grade (HG) zone. A detailed study of these incidents of blackleg outbreaks in North Finland during the years 2008 and 2010 indicated that Dickeya spp. was the major component in the observed blackleg complex. It was detected and isolated from almost all symptomatic plants investigated. Repetitive sequences PCR (REP‐PCR) and Pulsed Field Gel Electrophoresis (PFGE) analysis of strains isolated in Finland showed identical pattern with those isolated recently in other European countries with a proposed name ‘Dickeya solani’. Moreover, the dnaX gene sequence of the representative strains isolated in Finland indicated 100% similarity to the dnaX sequences of ‘D. solani’. The study presents the first report of a detailed analysis of bacteria involved in potato blackleg complex from natural field outbreaks in North Finland HG zone and characterisation of the ‘D. solani’ strains playing the major role in the disease complex.  相似文献   
13.
14.

Background  

The aim of the study was to investigate urine matrix metalloproteinase (MMP-2 and -9) activity, alkaline phosphatase/creatinine (U-AP/Cr) and gamma-glutamyl-transpeptidase/creatinine (U-GGT/Cr) ratios, glucose concentration, and urine protein/creatinine (U-Prot/Cr) ratio and to compare data with plasma MMP-2 and -9 activity, cystatin-C and creatinine concentrations in colic horses and healthy controls. Horses with surgical colic (n = 5) were compared to healthy stallions (n = 7) that came for castration. Blood and urine samples were collected. MMP gelatinolytic activity was measured by zymography.  相似文献   
15.
Biological Invasions - Native to the Ponto-Caspian region, the benthic round goby (Neogobius melanostomus) has invaded several European inland waterbodies as well as the North American Great Lakes...  相似文献   
16.
In vivo effects of the antidepressant fluoxetine on spleen antioxidant status of C57BL/6 mice were studied using a melanoma experimental model. After a 14‐day treatment with fluoxetine (10 mg kg?1 day?1, i.p.), the endogenous antioxidant non‐enzyme (glutathione) and enzyme (superoxide dismutase (SOD) and glutathione peroxidase (GPx)) defense systems in spleen of healthy animals were not changed; the lipid peroxidation (LP) was also unchanged. When B16F10 melanoma cells were introduced in C57BL/6 mice 2 h before fluoxetine treatment, a drug‐protective effect against the melanoma‐induced oxidative changes (increased LP and decreased total glutathione (GSH)‐level, as well as antioxidant enzyme activities) in spleen was observed. Fluoxetine dose‐dependently reduced the amounts of free oxygen radicals (hydroxyl and superoxide anion radicals), generated in chemical systems. Taken together, the present results suggest that fluoxetine, acting as antioxidant, prevents from melanoma‐induced oxidative changes in mice spleen. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
17.
Influence of elevated CO2 and O3 on Betula pendula Roth crown structure   总被引:4,自引:0,他引:4  
Elevated CO(2) and ozone effects were studied singly and in combination on the crown structure of two Betula pendula clones. Measurements were made at the end of the second fumigation period in an open-top-chamber experiment with 9-year-old trees. Shoot ramification (number of long and short daughter shoots), shoot length, and number of metamers, leaves and buds were measured at four positions in every tree. As a result of increased temperature, trees in chambers had longer shoots and more frequent shoot ramification than control trees not enclosed in chambers. Ozone treatment decreased shoot ramification significantly. Additionally, ozone treatment resulted in an increased number of metamers in one clone. There was no statistically significant interaction between ozone effect and crown position; however, there was a slight tendency for the lower crown to be more affected by ozone. Elevated CO(2) caused a significant increase in the number of long-shoot metamers. Therefore, 2x ambient CO(2) concentration partly ameliorated the negative effect of ozone because the increased number of leaves per shoot counteracted the decreased branching. Although the main effects of elevated ozone and CO(2) were similar in the two clones, slight, statistically insignificant, differences appeared in their responses when interactions with crown position were considered.  相似文献   
18.
The wavelike pattern of fetal T cell neogenesis is largely determined by the intermittent generation and exportation of waves of prothymocytes by the hemopoietic tissues in coordination with their gated importation by the thymus. Having previously shown that the importation of prothymocytes by the adult mouse thymus is also gated and that thymocytopoiesis proceeds in discrete (albeit overlapping) waves, we now demonstrate that prothymocytes are periodically exported in saturating numbers from the adult mouse bone marrow. Experiments in normal, radioablated, and parabiotic mice document the cyclical accumulation (3-5 wk) of prothymocytes in both the steady state and regenerating bone marrow, followed by their release into the blood approximately 1 wk before intrathymic gate opening. The results also show that circulating donor-origin thymocyte precursors can transiently ( approximately 1 wk) establish high level chimerism in the bone marrow after the mobilization of endogenous prothymocytes, presumably by occupying vacated microenvironmental niches. Hence, by analogy with the fetal state, we posit the existence of a feedback loop whereby diffusible chemokines of thymic origin regulate the production and/or release of bone marrow prothymocytes during each period of thymic receptivity. Because each resulting wave of thymocytopoiesis is accompanied by a wave of intrathymic dendritic cell formation, these coordinated events may help to optimize thymocyte selection as well as production.  相似文献   
19.
Glucose and mannitol diffusion in human dura mater   总被引:2,自引:0,他引:2       下载免费PDF全文
An in vitro experimental study of the control of the human dura mater optical properties at administration of aqueous solutions of glucose and mannitol has been presented. The significant increase of the dura mater optical transmittance under action of immersion liquids has been demonstrated. Diffusion coefficients of glucose and mannitol in the human dura mater tissue at 20 degrees C have been estimated as (1.63 +/- 0.29) x 10(-6)cm(2)/s and as (1.31 +/- 0.41) x 10(-6) cm(2)/s, respectively. Experiments show that administration of immersion liquids allows for the effective control of tissue optical characteristics that make dura mater more transparent, thereby increasing the ability of light penetration through the tissue.  相似文献   
20.
Previous work demonstrates that the biosynthetic precursor of cholesterol, desmosterol, is released from cells and that its efflux to high density lipoprotein or phosphatidylcholine vesicles is greater than that of newly synthesized cholesterol (Johnson, W. J., Fischer, R. T., Phillips, M. C., and Rothblat, G. H. (1995) J. Biol. Chem. 270, 25037-25046). Here we report that the release of individual precursor sterols varies with the efflux of newly synthesized zymosterol being greater than that of lathosterol and both exceeding that of newly synthesized cholesterol when using either methyl-beta-cyclodextrin or complete serum as acceptors. The transfer of newly synthesized lathosterol to methyl-beta-cyclodextrin was inhibited by actin polymerization but not by Golgi disassembly whereas that of newly synthesized cholesterol was inhibited by both conditions. Newly synthesized lathosterol associated with cellular detergent-resistant membranes more rapidly than newly synthesized cholesterol. Upon efflux to serum, newly synthesized cholesterol precursors associated with both high and low density lipoproteins. Stimulation of the formation of direct endoplasmic reticulum-plasma membrane contacts was accompanied by enhanced efflux of newly synthesized lathosterol but not of newly synthesized cholesterol to serum acceptors. The data indicate that the efflux of cholesterol precursors differs not only from that of cholesterol but also from each other, with the more polar zymosterol being more avidly effluxed. Moreover, the results suggest that the intracellular routing of cholesterol precursors differs from that of newly synthesized cholesterol and implicates a potential role for the actin cytoskeleton and endoplasmic reticulum-plasma membrane contacts in the efflux of lathosterol.  相似文献   
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