954 resultados para Creatinine Clearance
Resumo:
Some species of the genera Anabaena can produce various kinds of cyanotoxins, which may pose risks to environment and human health. Anabaena has frequently been observed in eutrophic freshwater of China in recent years, but its toxicity has been reported only in a few studies. In the present study, the toxicity of an Anabaena flos-aquae strain isolated from Lake Dianchi was investigated. Acute toxicity testing was performed by mouse bioassay using crude extracts from the lyophilized cultures. The mice exposed to crude extracts showed visible symptoms of toxicity and died within 10-24 h of the injection. Serum biochemical parameters were evaluated by the use of commercial diagnostic kits. Significant alterations were found in the serum biochemical parameters: alkaline phosphatase (AKP), gamma-glutamyl transpepticlase (gamma-GT), aspartate amino transferase (AST), alanine amino transferase (ALT), AST/ALT ratio, total protein content, albumin content, albumin/globulin (A/G) ratio, blood urea nitrogen (BUN), serum creatinine (Ssr), and total antioxidative capacity (T-AOC). Histopathological observations were carried out with hematoxylin and eosin (HE) stain under light microscope. Severe lesions were seen in the livers, kidneys, and lungs of the mice injected with crude extracts. The alterations of biochemical parameters were in a dose-dependent manner, and the severities of histological lesions were in the same manner. Based on biochemical and histological studies, this research firstly shows the presence of toxin-producing Anabaena species in Lake Dianchi and the toxic effects of its crude extracts on mammals. (C) 2008 Wiley Periodicals, Inc. Environ Toxicol 24: 10-18, 2009.
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To investigate the occupational exposure levels to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), indoor dust (n = 3) in workshops and hair samples from male workers (n = 64) were collected at two electrical and electronic equipment waste (E-waste) dismantling factories located in the LQ area in east China in July 11-13, 2006. Pre- and postworkshift urines (64 of each) were also collected from the workers to study oxidative damage to DNA using 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker. The concentrations of PCDD/Fs, PCDD/F-WHO-TEQs, PBDEs, PCBs and PCB-WHO-TEQs were (50.0 +/- 8.1) x 10(3), 724.1 +/- 249.6, (27.5 +/- 5.8) x 10(6), (1.6 +/- 0.4) x 10(9), (26.2 +/- 3.0) x 10(3) pg/g dry weight (dw) in dust, and (2.6 +/- 0.6) x 10(3), 42.4 +/- 9.3, (870.8 +/- 205.4) x 10(3), (1.6 +/- 0.2) x 10(6), 41.5 +/- 5.5 pg/g dw in hair, respectively. The homologue and congener profiles in the samples demonstrated that high concentrations of PCDD/Fs, PBDEs, and PCBs were originated from open burning of E-waste. The 8-OHdG levels were detected at 6.40 +/- 1.64 mu mol/mol creatinine in preworkshift urines. However, the levels significantly increased to 24.55 +/- 5.96 mu mol/mol creatinine in postworkshift urines (p < 0.05). Then, it is concluded that there is a high cancer risk originated from oxidative stress indicated by the elevated 8-OHdG levels in the E-waste dismantling workers exposed to high concentrations of PCDD/Fs, PBDEs, and PCBs.
Resumo:
An acute toxicity experiment was conducted to examine the distribution and depuration of microcystins (MCS) in crucian carp (Carassius aurutus) tissues. Fish were injected intraperitoneally with extracted MCs at a dose of 200 mu g MC-LR (where L = leucine and R = arginine) equivalent/kg body weight. Microcystin concentrations in various tissues and aquaria water were analyzed at 1, 3, 12, 24, and 48 h postinjection using liquid chromatography coupled with mass spectrometry. Microcystins were detected mainly in blood (3.99% of injected dose at 1 h), liver (1.60% at I h), gonad (1.49% at 3 h), and kidney (0.14% at 48 h). Other tissues, such as the heart, gill, gallbladder, intestine, spleen, brain, and muscle, contained less than 0.1% of the injected MCs. The highest concentration of MCs was found in blood (526-3,753 ng/g dry wt), followed by liver (103-1,656 ng/g dry wt) and kidney (279-1,592 ng/g dry wt). No MC-LR was detectable in intestine, spleen, kidney, brain, and muscle, whereas MC-RR was found in all examined fish tissues, which might result from organ specificity of different MCs. Clearance of MC-RR in brain tissue was slow. In kidney, the MC-RR content was negatively correlated with that in blood, suggesting that blood was important in the transportation of MC-RR to kidney for excretion.
Resumo:
Alterations in hematological indices such as decreases in blood cell counts (RBC), hematocrit (Ht) and hemoglobin (Hb) concentrations are key symptoms of anemia. However, few experiments were conducted to examine changes in hematological indices of fish exposed to microcystins that are believed to be fatal to circulatory systems of vertebrates. An acute toxicological experiment was designed to study hematological changes of crucian carp injected intraperitoneally (i.p.) with extracted microcystins at two doses, 50 and 200 mu g MC-LReqkg(-1) body weight. After being i.p. injected with microcystins, the fish exhibited behavioral abnormity. There were significant decreases in RBC in the high-dose group, and in Ht and Hb concentrations in both dose groups, while erythrocte sedimentation rate (ESR) significantly increased, indicating the appearance of normocytic anemia. There were no prominent changes in the three red cell indices, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH,), and mean corpuscular hemoglobin concentration (MCHC). Increases in blood urea nitrogen (BUN) and creatinine (CR) in both dose groups suggest the occurrence of kidney impairment. Alteration in blood indices was reversible at the low dose group. Conclusively, anemia induced by kidney impairment was a key factor to cause abnormity of swimming behaviors and high mortality of crucian carp. (c) 2007 Elsevier Ltd. All rights reserved.
Resumo:
A 1/20-scale, low speed model rig representing the fan and nacelle of a high bypass ratio jet engine has been tested under crosswind conditions. The flow conditions under which the intake flow separates and reattaches have been found to exhibit considerable hysteresis. This phenomenon has been examined by a careful test procedure in which the crosswind angle has been slowly increased and then decreased. Measurements of the hysteresis associated with separation and reattachment are presented for independent variations in stream-tube contraction ratio, ground clearance, fan operating point and Reynolds number. The results reveal that particular care must be taken to allow for any hysteresis when testing intakes under crosswind conditions. They also indicate that separation hysteresis is particularly sensitive to fan operating point and the position of the ground plane. These findings suggest that it is important for high Reynolds number intake tests and calculations to include a ground plane and a model of the downstream turbomachinery. © 2002 by the author(s).
Resumo:
A preliminary survey was carried out in April 2003 to estimate the levels of nonylphenol (NP), bisphenol-A (BPA) and residual DDTs in Lake Donghu. After then, the sediments of some areas of the lake were moved out for clearing the lake by the local government. Therefore, the variance of NP and BPA after the clearance of sediment in the surface water was determined from December 2003 to May 2004. Sediments, surface water and fish were collected from four sub-lake areas and the analytes were qualified by GC/MS in SIM mode after concentration onto an Oasis solid phase extraction cartridge. NP and BPA values ranged between 5.46-119.10 and 0.9913.42 mg/kg dw, respectively, in sediments, 75.2-179.6 and 15.1-62.5 mu g/L in surface water. Meanwhile, the bioaccumulation factors (BCFs) of NP and BPA were calculated in fish livers. Plasma vitellogenin (VTG), a sensitive biomarker showing oestrogenicity was detected in the captured male Wuchang bream (Megalobrama amblycephala Yih) and common carp (Cyprinus carpio). After sediment clearance, the concentrations of NP and BPA decreased to 0.65-25.04 and 0.04-21.32 mu g/L. The results indicate the presence of high-dose xenoestrogenic NP and BPA, probably major contributors which associate with VTG induction in Lake Donghu male fish.
Resumo:
川牛膝多糖(CP)是从传统中药川牛膝(Cyathula officinalis Kuan)中提取的一种活性多糖,现代药理研究表明川牛膝多糖是川牛膝许多生物活性的物质基础。本实验室前期进行了川牛膝多糖的提取、分离、结构鉴定及其部分活性研究,发现川牛膝中多糖含量非常高,在对川牛膝多糖活性的初步研究中也证实了其具有免疫调节作用。我们为了进一步了解其免疫调节活性,并为构效关系的研究奠定基础,对其进行了如下研究: 1. 通过体外毒性检测、淋巴细胞增殖实验、NK细胞杀伤活性和腹腔巨噬细胞吞噬中性红活性测定,发现川牛膝多糖在10~300μg/mL浓度范围内,对细胞无毒性作用;能够促进LPS诱导的B淋巴细胞增殖(P<0.01)、增强NK细胞杀伤活性(P<0.05)和PMΦ吞噬中性红活性(P<0.01),且随多糖浓度增高而增强;但其对ConA诱导的T淋巴细胞的增殖无促进作用(P>0.05)。 2. 通过正常小鼠体内淋巴细胞转化实验、迟发型变态反应分析、抗体生成细胞检测、碳粒廓清检测、腹腔巨噬细胞吞噬鸡红细胞活性和NK细胞活性测定,发现川牛膝多糖在适应性免疫方面能够促进SRBC免疫小鼠体内的抗体生成细胞的生成(P<0.01)和增强DNFB诱导的DTH(P<0.05),但对ConA诱导的脾淋巴细胞增殖无促进作用(P>0.05);在固有免疫方面能够提高小鼠碳粒廓清速率(P<0.05),PMΦ吞噬 CRBC 活性(P<0.01)和NK细胞杀伤活性(P<0.05)。同时还发现其对由环磷酰胺(Cy)引起的白细胞数下降具有很好的抑制作用(P<0.01)。 3. 为了获得结构明确、均一的保留活性的川牛膝多糖片段,为其作用机制、构效关系研究提供关键研究材料,我们开展了“保留免疫活性的最小片段”的分离制备的初步研究。建立并优化了川牛膝多糖的酸水解条件,发现在6%的样品浓度,0.025mol/L的硫酸浓度,65℃的水解温度,水解时间为8min的条件下可以得到一系列连续的多糖片段;采用Bio-Gel P2 分子筛柱层析分离得到5个级分,通过体外淋巴细胞增殖实验、NK细胞活性测定、腹腔巨噬细胞吞噬中性红实验发现其中的一个片段仍保留较强的免疫活性,并测得其分子量约为2057Da,为保留免疫活性的最小片段的进一步分离奠定了基础。 Cyathula officinalis Kuan is a commonly-used Traditional Chinese Medicine (TCM) with a wide range of pharmacological activities. Modern pharmacological researches showed the polysaccharide extracted from it (CP) is an important component for many bioactivities of this TCM. In the previous studies, we found CP showed significant immuno-regulative activities. In order to evaluate this activity systematically and lay foundations for revealling its immuno-regulative machanisms and the Structure -Function relationship, we carried out the following research works: 1. The in vitro immunoactivities of CP were evaluated by using normal mice immunocytes with respects to cytotoxicity, lymphocytes proliferation, NK activity and the ability of peritoneal macrophage phagocytizing neutral red. The polysaccharide showed no cytotoxicity below the concentration of 300 μg/mL, and could promote B lymphocytes proliferation (P<0.01), enhance NK activity (P<0.05) and the ability of peritoneal macrophage phagocytizing neutral red (P<0.01) at the concentration of 10-300 μg/mL. The above effects were positively correlated with the concentration of the polysaccharides. But it could not promote T lymphocytes proliferation (P>0.05). 2. The in vivo immunoactivities of CP were observed on normal mice through the following indices: splenic lymphocyte transformation efficiency, delayed-type allergy, antibody-forming cells activity (AFC), rate of carbon clearance, rate of peritoneal macrophage phagocytizing chicken red blood cell (CRBC) and NK activity, and its influence on the decline of the mouse leucocyte count induced by Cy. The polysaccharide at medium-dose enhanced delayed-type allergy (P<0.05)and NK activity(P<0.05) and increased the rate of carbon clearance(P<0.05), AFC activity(P<0.01) and the rate of peritoneal macrophage phagocytizing CRBC(P<0.01). The polysaccharides also effectively resisted the decline of the mouse leucocyte count induced by Cy(P<0.01). However, it couldn’t increase the splenic lymphocyte transformation efficiency(P>0.05). 3. Attempting to isolate and prepare the minimal fragments retaining activity with identical structure for further studying on immuno-regulative mechanism and Structure-Function relationship, we carried out the study on hydrolysis of CP, isolation of hydrolysed fragments, and the activity evaluation of the isolated fragments. CP with concentration of 6% was hydrolysed at 65℃ for 8 min with sulfuric acid of 0.025 mol/L,then the hydrolysate was separated using Bio-Gel P2 chromatography, 5 portions of fragments were obtained. The immunoactivities of these fragments were evaluated by using normal mice immunocytes with respect to lymphocytes proliferation, NK activity and ability of peritoneal macrophage phagocytizing neutral red. One fragment with relative molecular mass of 2057Da was found retaining immunoactivity.
Resumo:
8-hydroxy-2'-deoxyguanosine (8OHdG) has been widely used as a biomarker of oxidative DNA damage in both animal models and human studies. To evaluate the effect of cigarette smoking on oxidative stress, we studied the levels of urinary 8OHdG from smokers and non-smokers and investigated the association with cigarette smoking. The urinary 8OHdG concentrations were determinated by capillary electrophoresis with end-column amprometric detection (CE-AD) after a single-step solid phase extraction (SPE), and then quantitatively expressed as a function of creatinine excretion. To increase the concentration sensitivity, a dynamic pH junction was used and the focusing effect was obvious when using 30 mM phosphate (pH 6.50) as sample matrix. The limit of detection is 4.3 nM (signal-to-noise ratio S/N = 3). The relative standard deviation (R.S.D.) was 1.1% for peak current, and 2.3% for migration time. Based on the selected CE-AD method, it was found that the mean value of urinary 8OHdG levels in the smokers significantly higher than that in non-smokers (31.4 +/- 18.9 nM versus 14.4 +/- 7.6 nM, P = 0.0004; 23.5 +/- 21.3 mug g(-1) creatinine versus 12.6 +/- 13.2 mug g(-1) creatinine, P = 0.028). (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
Increased oxidative stress induced by hyperglycemia may contribute to the pathogenesis of diabetic complications. Urinary 8-hydroxydeoxyguanosine (8-OHdG) has been reported to serve as a sensitive biomarker of oxidative DNA damage and also of oxidative stress. This article studied oxidative DNA damage in patients with diabetic nephropathy and in healthy control subjects by urinary 8-OHdG evaluations. Contents of 8-OHdG in urine were analyzed by capillary electrophoresis with end-column amperometric detection (CE-AD) after a single-step solid-phase extraction (SPE). Levels of urinary 8-OHdG in diabetic nephropathy patients with macroalbuminuria was significant higher than in control subjects (5.72 +/- 6.89 mumol/mol creatinine versus 2.33 +/- 2.83 mumol/mol creatinine, P = 0.018). A significant difference of 24 h urinary 8-OHdG excretions exists between the patients with macroalbuminuria and the patients with nonnoalbuminuria (19.2 +/- 16.8 mug/24 h versus 8.1 +/- 1.7 mug/24 h, P = 0.015). There was a positive correlation between urinary excretion of 8-OHdG and glycosylated hemoglobin (HbA(1)c) (r = 0.287, P = 0.022). A weak correlation exists between the levels of 8-OHdG and triglyceride (r = 0.230, P = 0.074). However, the urinary 8-OHdG contents are not correlated with blood pressure and total cholesterol. The increased excretion of urinary 8-OHdG is seen as indicating an increased systemic level of oxidative DNA damage in diabetic nephropathy patients. (C) 2004 Elsevier B.V. All rights reserved.
Resumo:
This paper gives a capillary electrophoretic method for the separation of 15 urinary normal and modified nucleosides from cancer patients in less than 40 min. A 500 mmx50 mu m uncoated capillary column (437.5 mm to window) was used. The effects of the voltage and the sodium dodecyl sulfate (SDS) concentration in the buffer on the separation were studied. With reproducibilities of migration times better than 1.2% (R.S.D.) and determined concentrations better than 5-25%, depending on the concentrations of nucleosides in the urine, the analytical characteristics of the method were food. Using this developed method, the concentrations of 13 normal and modified nucleosides, extracted on a phenyl boronic acid affinity chromatography column, in 25 urines from patients of 14 kinds of cancer were determined. The levels (nmol/mol creatinine) of modified nucleosides in urines from cancer patients were increased as compared with those in normal urines. (C) 1998 Elsevier Science B.V.
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High resolution H-1 nuclear magnetic resonance ( NMR) spectroscopy has been employed to assess long-term toxicological effects of ChangLe (a kind of rare earth complex applied in agriculture). Male Wistar rats were administrated orally with ChangLe at doses of 0, 0.1, 0.2, 2.0, 10 and 20 mg/kg body weight daily, respectively, for 6 months. Urine was collected at-day 30, 60, go and serum samples were taken after 6 months. Many low-molecular weight metabolites were identified by H-1 NMR spectra of rat urine. A decrease in citrate and an increase in ketone bodies, creatinine, DMA, DMG, TMAO, and taurine in the urine of the rats. receiving high doses were found by H-1 NMR spectra. These may mean that high-dosage of ChangLe impairs the specific region of liver and kidney, such as renal tubule and mitochondria. The decrease in citrate and the increase in succinate and alpha-ketoglutarate were attributed to a combination of the inhibition of certain citric acid enzymes, renal tubular acidosis and the abnormal fatty acid catabolism. The information of the renal capillary necrosis could be derived from the increase in DMIA, DMG and TMAO. The increase in taurine was due to hepatic mitochondria dysfunction. The conclusions were supported by the results of biochemical measure. merits and enzymatic assay.
Resumo:
H-1 NMR spectroscopy has been used to assess long-term toxicological effects of a rare earth. Male Wistar rats were administrated orally with La(NO3)(3) at doses of 0.1, 0.2, 2.0, 10, and 20 mg/kg body wt, resp., for 3-6 months. Urine was collected at 1, 2, and 3 months and serum samples were taken after 6 months. Numerous low-M-r metabolites in rats serum and rats urine, including creatinine, citrate, glucose, ketone bodies, trimethylamine N-oxide (TMAO), and various amino acids, were identified on 400- and 500-MHz H-1 NMR spectra. La3+-induced renal and liver damage is characterized by an increase in the amounts of the excreted ketone bodies, amino acids, lactate, ethanol, succinate, TMAO, dimethylamine, and taurine and a decrease in citrate, glucose, urea, and allantoin. Information on the molecular basis of the long-term toxicity of La(NO3)(3) was derived from the abnormal patterns of metabolite excretions. An assay of some biochemical indexes and analysis of some enzymes in plasma supported NMR results.
Resumo:
C-type lectins are a superfamily of carbohydrate-recognition proteins which play crucial roles in the innate immunity. In this study, the gene of a C-type lectin with multiple carbohydrate-recognition domains (CRDs) from scallop Chlamys farreri (designated as Cflec-3) was cloned by rapid amplification of cDNA ends (RACE) approach based on expression sequence tag (EST) analysis. The full-length cDNA of Cflec-3 was of 2256 bp. The open reading frame encoded a polypeptide of 516 amino acids, including a signal sequence and three CRDs. The deduced amino acid sequence of Cflec-3 showed high similarity to members of C-type lectin superfamily. By fluorescent quantitative real-time PCR, the Cflec-3 mRNA was mainly detected in hepatopancreas, adductor, mantle, and marginally in gill, gonad and hemocytes of healthy scallops. After scallops were challenged by Listonella anguillarum, the mRNA level of Cflec-3 in hemocytes was up-regulated and was significantly higher than that of blank at 8 h and 12 h post-challenge. The function of Cflec-3 was investigated by recombination and expression of the cDNA fragment encoding its mature peptide in Escherichia coli BL21 (DE3)-pLysS. The recombined Cflec-3 (rCflec-3) agglutinated Gram-negative bacteria Pseudomonas stutzeri. The agglutinating activity was calcium-dependent and could be inhibited by D-mannose. These results collectively suggested that Cflec-3 was involved in the immune response against microbe infection and contributed to nonself-recognition and clearance of bacterial pathogens in scallop. (C) 2009 Elsevier Ltd. All rights reserved.