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1.
To assess the relative importance of long‐ and short‐term cellular defense mechanisms in seasonally UV‐R‐acclimated Actinia tenebrosa (Anthozoa, Actiniidae), individuals were exposed to summer doses of PAR, UV‐A, UV‐B and enhanced UV‐B (20%) for a period of 4 days. Mycosporine‐like amino acids (MAAs) and cyclobutane pyrimidine dimer (CPD) concentrations were quantified, while oxidative damage to lipids and proteins, and the activities or levels of the antioxidant enzymes SOD, CAT, GR, GPOX and total glutathione were determined. Our results show that summer UV‐R‐acclimated individuals had a higher UV‐R tolerance, with no significant increases in CPDs levels, than winter‐acclimated sea anemones possibly due to higher MAA concentrations. Summer‐acclimated individuals showed increased lipid and protein oxidation and GPOX activity only when they were exposed to UV‐B at 20% above ambient UV‐R levels. In contrast, winter‐acclimated sea anemones showed elevated levels of oxidative damage, GPOX and SOD activities after exposure to UV‐A or UV‐B at ambient and elevated levels. Thus, this study indicates that long‐term UV‐R acclimation mechanisms such as the accumulation of MAAs could be more important than short‐term increases in antioxidant defenses with respect to reducing indirect UV‐R damage in intertidal sea anemones.  相似文献   

2.
An investigation was carried out to find whether enhanced levels of UV-B radiation induce increased concentrations of flavonoids in the leaves of the grass species Deschampsia antarctica, Deschampsia borealis and Calamagrostis epigeios and the sedge Carex arenaria. Whether the enhanced levels of UV-B influenced the proportions of the various flavonoids in the leaves was also studied. Increased flavonoid concentrations would improve the UV-B shielding of UV-B susceptible tissues. Using HPLC analysis the flavonoids orientin and luteolin were identified in D. antarctica, orientin in D. borealis and tricin in C. arenaria. Neither flavonoid concentrations nor the proportion of the various flavonoids in climate room grown D. antarctica and D. borealis plants differed between individuals grown under 0, ambient or elevated UV-B levels. After 12 weeks of growth biomass production and shoot-to-root ratios of D. antarctica were not affected by elevated UV-B radiation. Greenhouse grown C. epigeios plants contained higher concentrations and different proportions of flavonoids grown under elevated levels of UV-B than when grown under ambient or 0 UV-B. In C. epigeios plants grown in their natural habitat in the field under ambient or elevated levels of UV-B, flavonoid concentrations and proportions were the same in plants from both treatments. In the leaves of the sedge C. arenaria grown in a greenhouse flavonoid concentrations and proportions were not affected by UV-B radiation. Leaves were harvested four times during the growing season from C. arenaria plants grown in their natural habitat in the field under ambient or elevated levels of UV-B. Leaves harvested in January contained higher concentrations of flavonoids when grown under elevated UV-B than when grown under ambient UV-B radiation. In leaves harvested in May, September and December flavonoid concentrations were the same in plants grown under ambient or elevated UV-B. The proportion of the different flavonoids was the same for both treatments in all months. These results indicate that constitutive levels of flavonoids in these grass and sedge species are adequately high to protect them against ambient and elevated levels of solar UV-B radiation.  相似文献   

3.
BackgroundThe association between inflammatory cysteinyl aspartate protease-5 (CASP5) and the susceptibility to rheumatoid arthritis (RA) remains unclear. This study examined whether the CASP5 rs7939842 polymorphism affects RA risk in Chinese Han individuals.MethodsThis study recruited 805 RA patients and 1095 healthy controls to investigate the association between the CASP5 rs7939842 polymorphism and RA risk. Genotype was examined using the 48-Plex SNPscan? Kit. Plasma CASP5 levels were determined using enzyme-linked immunosorbent assays, and CASP5 gene expression was detected by quantitative polymerase chain reaction in 40 RA patients and 40 healthy controls.ResultThe CASP5 rs7939842 polymorphism G allele is a putative risk factor for RA. After stratified analyses, this polymorphism increased the risk of RA among CRP-, ACPA-, RF-, and ESR-positive individuals, as well as individuals with DAS28 ≥ 3.20 and functional class III + IV. Furthermore, the plasma CASP5 levels and CASP5 mRNA expression were higher in RA patients than in healthy controls.ConclusionThe CASP5 rs7939842 polymorphism appears to be associated with an elevated risk of RA in Chinese Han individuals. Blood CASP5 protein and mRNA levels were significantly higher in RA patients than in healthy controls.  相似文献   

4.
Summary Experiments, with animals and with cultured vascular wall cells as well as clinical observations on patients suffering from pheochromocytoma, favour the hypothesis that catecholamines could play an important role in the pathogenesis of arteriosclerosis. As the catecholamines, adrenaline and/or noradrenaline, promote metabolic dysfunctions in vascular wall cells, which are important in the pathogenesis of arteriosclerosis, these compounds may well be acting as chemical mediators during atherogenesis. Therefore investigations on plasma catecholamine levels in patients, exposed to atherogenic risk factors, with different stages of arteriosclerosis, and in patients suffering from thrombotic complications of an arteriosclerotic vascular disease, may lead to an answer for the question of whether or not plasma catecholamine levels are of clinical importance in the pathogenesis of arteriosclerosis in man.In individuals subjected to the atherogenic risk factors, smoking, essential hypertension, and mental stress, plasma catecholamine levels were statistically significantly elevated. In patients suffering from diabetes mellitus plasma adrenaline and noradrenaline concentrations however were similar to those of healthy controls. In dialysis patients, who often develop arteriosclerosis which progresses with great rapidity, plasma adrenaline and noradrenaline concentration showed a positive correlation with different stages of arteriosclerosis; i.e. plasma catecholamine concentration increases with the severity of this disease. Arteriosclerotic vascular diseases sometimes give rise to thrombotic complications, the most prominent ones being myocardial infarction and stroke. Compared with healthy controls, even one year after infarction, 70% of the patients who had had a myocardial infarction and 50% of the stroke patients had significantly elevated plasma adrenaline and/or noradrenaline levels. Further investigations on patients suffering from coronary heart disease showed that elevated plasma catecholamine concentration is more probably related to the pathogenesis of the vascular disease than to the incurrence of myocardial infarction.From these data we conclude that catecholamines are substances that can act as chemical mediators during the pathogenesis of arteriosclerosis in man and thus may contribute to the development and subsequent complications of this important vascular disease.  相似文献   

5.
Abstract

High Performance Gel Permeation Chromatography (GPC) was evaluated as an alternative to the more expensive Nuclear Magnetic Resonance (NMR) spectros-copy technique presented by Fossel and co-workers (1) for cancer detection using human plasma. These two techniques show a biphasic relationship which can be explained on the basis of the relative amounts of the lipoprotein levels present in the plasma and a good correlation (Table 1) with total triglyceride concentrations obtained from standard blood tests. The major difference in the GPC elution-profiles (254 nm) of plasma from normal individuals and that from cancer patients occurred in the peak eluting at the void volume. This peak has a retention time consistent with very low density lipoprotein (VLDL) and is elevated in most cancer patients and in normal patients with triglyceride levels greater than 200 mg/ml. The use of these techniques as a screening test for cancer in an asymptomatic population needs further evaluation.  相似文献   

6.
In this paper, we first presented a novel method for quantification of circulating DNA in human serum based on capillary zone electrophoresis with laser-induced fluorescence detection (CZE-LIF). The serum was digested by proteinase to release free DNA, and then CZE-LIF system was used for the quantification of total circulating DNA. This method was successfully used to quantify the circulating DNA levels in sera from healthy individuals and certain cancer patients.We found the significantly elevated circulating DNA levels in certain prostate cancer patients. Our results demonstrated that CZE-LIF system has good linearity, excellent sensitivity (0.5 ng/mL DNA),satisfactory reproducibility (RSDs in one day and between days were both less than 5%) and reliability, and is well suitable to the quantification of the circulating DNA in human serum or plasma.  相似文献   

7.
Bikunin is a plasma proteinase inhibitor often associated with inflammatory conditions. It has a half‐life of few minutes and it is rapidly excreted into urine as urinary trypsin inhibitor (UTI). UTI levels are usually low in healthy individuals but they can increase up to tenfold in both acute and chronic inflammatory diseases. This article describes a sensitive method for both direct UTI quantitation and structural characterization. UTI purification was performed by anion exchange micro‐chromatography followed by SDS‐PAGE. A calibration curve for protein quantitation was set up by using a purified UTI fraction. UTI identification and structural characterization was performed by Nano‐LC‐MS/MS analysis. The method was applied on urine samples from 9 patients with type 1 diabetes, 11 patients with type 2 diabetes, and 28 healthy controls, matched for age and sex with patients, evidencing higher UTI levels in both groups of patients with respect to controls (p < 0.001 and p = 0.001, respectively). Spearman's correlation tests highlighted no association between UTI levels and age in each group tested. Owing to the elevated sensitivity and specificity, the described method allows UTI quantitation from very low quantities of specimen. Furthermore, as UTI concentration is normalized for creatinine level, the analysis could be also performed on randomly collected urine samples. Finally, MS/MS analysis prospects the possibility of characterizing PTM sites potentially able to affect UTI localization, function, and pathophysiological activity. Preliminary results suggest that UTI levels could represent a useful marker of chronic inflammatory condition in type 1 and 2 diabetes.  相似文献   

8.
Trace element levels in hair of individuals living in urban areas were determined by energy dispersive XRF. Two groups of subjects were investigated, the first group was assumed to be from a healthy environment, the other one was exposed to a high level of contamination due to working conditions. The results were compared to data reported in the literature. The concentrations of Ca, Fe, Cu, Zn and Pb in the scalp hair were determined and the correlation between hair trace element levels and environmental effects was discussed. The results given by the second group show that environmental exposure effects hair trace element levels which are related to body trace element concentrations.  相似文献   

9.
肝硬化患者血清微量元素与免疫功能的相关性研究   总被引:1,自引:0,他引:1  
为探讨肝硬化患者血清中微量元素含量与细胞免疫功能的相关性,将70例肝硬化患者根据代偿期及失代偿期分为两组,30例健康体检者为对照组,用日立7170A型全自动生化分析仪检测了血清中的镁、铁、铜、锌含量,流式细胞技术检查了外周血CD3+、CD4+、CD8+、NK细胞。结果表明,肝硬化患者血清镁、铁、锌水平显著低于对照组;血清铜水平显著高于对照组;CD3+、CD4+、NK细胞低于正常对照组,以失代偿期改变明显。肝硬化患者血清铜水平与CD3+、CD4+、NK细胞呈负相关,血清锌水平与CD3+、CD4+、NK细胞呈正相关。提示肝硬化患者微量元素代谢异常与细胞免疫功能下降有一定的联系。  相似文献   

10.
In vitro incubations were performed to show that homocysteine thiolactone could generate covalent adducts with model peptides and proteins. MS and MS/MS data suggest that the thiolactone reacts with the side-chain amino group of lysine residues as well as with the N-terminal amino group or C-terminal carboxy group. For larger peptides and proteins, the contribution from the in-amino groups of lysine residues should be predominant. These data could help explain the detrimental effects of elevated levels of homocysteine and homocysteine thiolactone.  相似文献   

11.
Instrumental neutron activation analysis has been performed on human head hair of newborns and mothers sampled in two areas with a different level of environmental exposure. The group of neonates from the exposed area (polluted by thermal power plants burning brown coal and by chemical industry) has exhibited higher levels of several trace elements in hair, e.g. Se, Zn, Hg and Sb in comparison with the control group. Moreover, the mean concentrations of Se, Hg, Zn and Br in neonate hair have been found to be higher than in mothers hair. Although the study revealed statistically significant differences in the composition of neonate hair sampled in areas with different levels of environmental exposure, the differences are relatively small. Only a thorough long-term study both with environmental and medical observations can prove a direct connection of the elevated levels of some trace elements in neonate hair with the higher frequency of mental diseases of children living in the exposed area.  相似文献   

12.
Deoxyribonucleic acid (DNA) methylation patterns can be used to identify the type of tissue or body fluid found at a crime scene. However, tissue-related methylation levels have not been analyzed in individuals with different illnesses and medical conditions in forensic-specific studies. The primary goal of this study was to investigate if certain clinical phenotypes can alter the methylation levels of CpG sites in genes involved in tissue typing. Four studies with focus on DNA methylation analysis on individuals with different clinical conditions were selected from the Gene Expression Omnibus database. Then, a list of 137 CpG sites was compiled for further investigation. Statistical tests were performed to compare the beta-values results obtained for the control groups and the individuals affected by medical conditions. For each study, CpG sites that presented significant statistical differences between patients and control group were identified and it was possible to notice that DNA methylation levels can be affected in sites with potential forensic use. Although the observed DNA methylation variation (less than 10% difference) in this study would likely not cause any issues in body fluid identification, the results are important to show that this type of analysis should be taken into consideration when investigating and further validating body fluid markers. The CpG sites identified in this study should be further investigated by future studies on body fluids identification, and due to the significant difference in methylation levels in samples from affected individuals, caution must be taken before including these sites in tissue identification investigations.  相似文献   

13.
Macroalgae distributed in intertidal zones experience a series of environmental changes, such as periodical desiccation associated with tidal cycles, increasing CO2 concentration and solar UVB (280–315 nm) irradiance in the context of climate change. We investigated how the economic red macroalga, Pyropia haitanensis, perform its photosynthesis under elevated atmospheric CO2 concentration and in the presence of solar UV radiation (280–400 nm) during emersion. Our results showed that the elevated CO2 (800 ppmv) significantly increased the photosynthetic carbon fixation rate of P. haitanensis by about 100% when the alga was dehydrated. Solar UV radiation had insignificant effects on the net photosynthesis without desiccation stress and under low levels of sunlight, but significantly inhibited it with increased levels of desiccation and sunlight intensity, to the highest extent at the highest levels of water loss and solar radiation. Presence of UV radiation and the elevated CO2 acted synergistically to cause higher inhibition of the photosynthetic carbon fixation, which exacerbated at higher levels of desiccation and sunlight. While P. haitanensis can benefit from increasing atmospheric CO2 concentration during emersion under low and moderate levels of solar radiation, combined effects of elevated CO2 and UV radiation acted synergistically to reduce its photosynthesis under high solar radiation levels during noon periods.  相似文献   

14.
Nitrate is regarded as a substance whose presence in drinking water is not considered as desirable. If reduced to nitrite it may cause methomoglobinemia in infants. Onward reaction with amines capable of coupling will result in the formatin of nitrosamins. Excessive use of fertilizers in agriculture is the most frequent cause of elevated nitrate contents of drinking water. To quantify this problem, drinking water was sampled at taps at 200 sites arranged on a grid covering the wine-growing areas of Baden and Württember. These samples were examined for their content of nitrate, chloride, and sulphate by means of ion chromatography. Clearly elevated nitrate contents were revealed by the resuls of measurements: 13% of samples showed values above the maximal concentration admissible under the EC Drinking Water Directive of 50 mg NO-3/l and 42% above the EC guide level. The excessive levels were mostly found in the regions of Kaiserstuhl-Tuniberg-Markgr?flerland and Württembergisch Unterland. Many samples with an elevated nitrateacontent exhibited also elevated sulphate contents. The high nitrate levels are attributed to the use of nitrogen fertilizers in the vineyards.  相似文献   

15.
研究了雄黄对大鼠脑组织氨基酸类神经递质含量的影响.将32只Wistar大鼠随机分为对照组(0.5%CMC-Na)以及低剂量(0.3g/kg)、中剂量(0.9g/kg)、高剂量(2.7g/kg)雄黄染毒组,通过连续灌胃给予雄黄混悬液两周.采用高效液相色谱-柱前衍生化法测定了大鼠脑组织中氨基酸类神经递质含量的变化.结果表明,与对照组比较,低剂量组大鼠脑组织中丝氨酸、甘氨酸和γ-氨基丁酸含量明显增加.中、高剂量组大鼠脑组织中同型半胱氨酸、谷氨酰胺、丝氨酸和天冬氨酸含量明显比对照组的低.总体而言,雄黄可对大鼠脑组织氨基酸类神经递质产生影响,氨基酸类神经递质可能是雄黄毒性作用的靶点之一.  相似文献   

16.
Three genotypes of rapid-cycling Brassica rapa that differ in anthocyanin content were grown in the presence and absence of elevated levels of shortwave ultraviolet (UVB, 280–325 nm) radiation. After 41 days, UVB exposure reduced leaf length and plant height of all genotypes. Plants with low levels of anthocyanin experienced a reduction in flower number twice as great as in genotypes with normal or elevated levels of anthocyanins; however, the absence of differences in flower production by genotypes with normal and elevated levels of anthocyanins suggests that factors other than anthocyanin pigmentation contribute to UVB responses in this species.  相似文献   

17.
18.
In the search for new potential antihyperlipidemic agents, the present study focuses on the synthesis of novel N-(benzoylphenyl)-5-substituted-1H-indole-2-carboxamides (compounds 8-12, 15, 16, 18) and investigating their antihyperlipidemic activity using Triton WR-1339-induced hyperlipidemic rats as an experimental model. Hyperlipidemia was developed by intraperitoneal injection of Triton WR-1339 (250 mg/kg body weight). The tested animals were divided into normal control (NCG), hyperlipidemic (HG), compound 8, 9, 15, 16, 18- and bezafibrate treated groups. At a dose of 15 mg/kg body weight, compounds 9, 16, 18 and bezafibrate (100 mg/kg) significantly (p < 0.0001) reduced elevated plasma triglycerides levels after 12 h compared to the hyperlipidemic control group. However, only the group treated with compounds 9, 16 and 18 showed an obviously significant (p < 0.001) reduction in plasma total cholesterol levels after 12 h compared to the hyperlipidemic control group. Moreover, high density lipoprotein-cholesterol levels were significantly (p < 0.0001) increased in all treated groups after 12 h compared to the hyperlipidemic control group, except for compounds 8 and 15 which revealed inactive. It is therefore reasonable to assume that compounds 9, 16 and 18 may have potential in the treatment of hyperlipidemia.  相似文献   

19.
20.
The activity levels of serum monoamine oxidase in nutritional (alcoholic) liver disease patients were elevated beyond the upper normal limit, while those of other subjects without pathologically accelerated fibrosis ranged within normal values. Capillaroscopic and plethysmographic studies on finger reactive hyperemia revealed that two characteristic changes in the blood microcirculation, which indicated an occurrence of increased fibritic process in the capillary wall and skin tissues, were observed only in the nutritional (alcoholic) liver disease patients with the elevated serum monoamine oxidase levels. These results suggested that nutritional (alcoholic) liver disease is not a disease restricted to liver tissues, but to a disorder creating pathological fibrosis in the whole-body.  相似文献   

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