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1.
The present study was conducted to investigate the effectiveness of propolis in alleviating the toxicity of propetamphos on haematological and biochemical parameters in rats. Twenty-four female Wistar–Albino rats (200–250 g) were randomly divided into four equal groups of six rats each. As normal drinking water was given to the control group, propolis (100 mg/kg bw/day), propetamphos (15 mg/kg bw/day), and propolis (100 mg/kg bw/day) with propetamphos (15 mg/kg bw/day) combinations were given to the other three groups by adding to drinking water for 28 days, respectively.  相似文献   

2.
The endemic of chronic renal failure (CRF) emerged in 2002 in the farming provinces of Sri Lanka. An estimate of dietary cadmium intake was between 15 and 28 μg/kg body weight per week. The mean urinary cadmium in patients diagnosed with stage 5 kidney failure was 7.6 μg/g creatinine and 11.6 μg/g for asymptomatic persons. The agrochemical triple superphosphate (TSP) fertilizer containing 23.5–71.7 mg Cd/kg was the source of cadmium added to soils. Mean Cd content in cultivated vs. uncultivated soils in Anuradhapura district was 0.02 ± 0.01 vs. 0.11 ± 0.19 mg/kg while in Polonnaruwa district, it was 0.005 ± 0.004 vs. 0.016 ± 0.005 mg/kg. Prior to the Green Revolution, the amount of fertilizer used in rice cultivation in 1970 was 32,000 metric tons (Mts) rising to 74,000 Mts in 1975. Up to 68.9 Mts of Cd could have entered into the rice-cascade reservoir environment from TSP use since 1973. Diversion of the Mahaweli River in 1970–1980 further increased cadmium input. Cadmium transfer from Upper Mahaweli water to Polgolla was 72.13 kg/day. Cadmium content of the sediments from reservoirs collecting cadmium from irrigated TSP fertilized crop fields (rice and vegetables) was 1.8–2.4 mg/kg.  相似文献   

3.
Analysis of phenolic compounds in sixteen Portuguese wild mushrooms species has been carried out by high-performance liquid chromatography coupled to photodiode array detector and mass spectrometer (HPLC–DAD–ESI/MS). No flavonoids were detected in the analysed samples, but diverse phenolic acids namely protocatechuic, p-hydroxybenzoic and p-coumaric acids, and two vanillic acid isomers were found and quantified. A related non-phenolic compound, cinnamic acid, was also detected in some samples, being the only compound found in Cantharellus cibarius (14.97 mg/kg, dry matter), Lycoperdon perlatum (14.36 mg/kg) and Macrolepiota procera (21.53 mg/kg). p-Hydroxybenzoic acid was found in the majority of the samples, being the most abundant compound in Agaricus silvicola (238.7 mg/kg). Ramaria botrytis showed the highest phenolic acids concentration (356.7 mg/kg) due to the significant contribution of protocatechuic acid (342.7 mg/kg).  相似文献   

4.

Objective

To analyse the distribution of caffeine doses obtainable from espresso coffee sold by a sample of commercial coffee vendors located on the Gold Coast, Qld, Australia.

Design

A cross section of “Espresso/short black” coffee samples were purchased and analysed for their caffeine content using micellar electrokinetic capillary chromatography (MEKC). Coffees were collected using systematic cluster sampling across five major retail centres.

Results

Ninety-seven espresso samples were analysed. The mean (±SD) quantity of caffeine was 106 ± 38 mg/serve with a concentration of 2473 ± 1092 mg/l. There was considerable variation in caffeine content. The range per serve was 25–214 mg whilst the concentration range was 580–7000 mg/l. Twenty-four samples (24.7%) contained 120 mg of caffeine or higher and 12 samples (12.3%) exceeded 167 mg per serve.

Conclusions and implications

The number of heavily caffeinated samples differentiates these findings from frequently cited caffeine values and supports similar data recently collected throughout the United Kingdom. As a result, the accuracy of any previous intake modelling regarding caffeine use in the Australian population is in doubt. The present data suggests that the probability of consumer exposure to high caffeine doses is greater than previously anticipated. Greater sample numbers from a broader selection of venues is required to confirm the extent of caffeine content variance within retail ground coffees.  相似文献   

5.
In this work, 64 samples of cereals purchased from local markets in the Valencian community (Spain) were investigated for the presence of six emerging mycotoxins: enniatins ENs (ENA, ENA1, ENB and ENB1), beauvericin (BEA) and fusaproliferin (FUS). Samples were extracted with a mixture of water/acetonitrile (85/15, v/v) by using an Ultra-turrax homogenizer. Mycotoxins were then identified and quantified with a liquid chromatography (LC) with diode array detector (DAD). Positive samples were confirmed with an LC–MS/MS. Analytical Results showed that the frequencies of contamination of samples with ENs, BEA and FUS were 73.4%, 32.8% and 7.8%, respectively. ENA1 was the most mycotoxin found and levels ranged from 33.38 to 814.42 mg/kg. ENB levels ranged between 2.23 and 21.37 mg/kg. ENB1 levels varied from 4.34 to 45.94 mg/kg. All samples were free of ENA. BEA levels ranged from 0.51 to 11.78 mg/kg and FUS levels varied between 1.01 and 6.63 mg/kg. It could be concluded from this study that the high contamination levels found especially for ENs could be of a negative impact on the population. This is the first paper on the presence of emerging mycotoxins in cereals available in Spain.  相似文献   

6.
In this study, the contents of total mercury (Hg) present in poultry feed, tissues of broiler chicken and manure were assessed. For this purpose, chicken feeds (five brands), different tissues of broiler chicken of two age groups (1–3 and 4–6 week) and manure samples were collected from five commercial poultry farms of Hyderabad, Pakistan. The Hg concentrations in feeds, chicken tissues (leg, muscle, liver and heart) and manure samples were determined by CVAAS, prior to microwave assisted acid digestion in closed vessels. For validation, a certified reference material, DORM-2 was used. The limit of detection and quantitation were 0.117 and 0.382 μg/kg, respectively The Hg concentration in different chicken feed were found in the range of 8.57–16.5 μg/kg. The concentration of Hg in chicken tissues were found in the range of 2.54–5.54 μg/kg (liver), 1.27–3.86 μg/kg (muscles) and 2.13–3.27 μg/kg (heart). The bioaccumulation factors (BAF) for Hg in different tissues were found in the range of 0.092–0.269. The obtained data shows the high correlation coefficient between feed and manure, while low r-values were obtained between Hg levels in feed and tissues of broiler chicken of two age groups.  相似文献   

7.
The aim of this study was to evaluate the uptake of arsenic (As) by grain crops (wheat, maize and sorghum) grown on agricultural soil irrigated with tube well water (SIT) as test samples and for comparative purposes, same grain crop samples grown on agricultural soil irrigated with fresh canal water (SIC) were marked as control samples, collected simultaneously from three sub-districts of Khairpur, Pakistan. Moreover, this paper demonstrated the total and EDTA (0.05 M) extractable As in both understudied soils that correlate with the respective total As in the edible parts of the studied grain crops. A significantly high accumulation of As was found in grains grown on SIT as compared to those grown on SIC. This study highlights the increased danger of growing food crops in the agricultural land continuously irrigated by As contaminated ground water.  相似文献   

8.
The essential elements and contaminants (Pb and Cd) were determined seasonally in the muscle and liver of six demersal fish species Sparus aurata, Chelidonichthys lucernus, Upeneus molluccensis, Solea solea, Merluccius merluccius and Saurida undosquamis from the ?skenderun Bay, Eastern Mediterranean Sea. The concentrations in muscles of fish species were 474–1534 mg/kg for Na, 574–3374 mg/kg for K, 72.7–496 m/kg Ca, 94.1–210 mg/kg for Mg. Muscle accumulated the lowest levels of elements. Trace element and contaminant levels in muscle were highest in the spring and winter. The Cu and Ni concentrations were highest in the winter. The Zn, Cr and Fe concentrations were highest in the spring. The maximum Pb concentrations in the muscle and liver of fish species was 0.58 and 0.89 mg/kg (wet wt) in the autumn. The maximum Cd concentration in the muscle and liver tissues of fish was 0.20 mg/kg and 0.63 mg/kg (wet wt) in the winter. The Cr, Pb, Cd, Cu and Zn levels in muscle were found to be lower than permissible limits. Estimated weekly and daily intake for Pb and Cd was far below the PTWI and PTDI values. The consumption of these species from this region is not problem on human health.  相似文献   

9.
Evidence suggests that the health benefits associated with green tea consumption are related to tea catechins. The objective of this study was to evaluate potential maternal and fetal effects of standardized heat-sterilized green tea catechins (GTC-H). GTC-H was gavage administered to mated female rats from gestation day 6 through 17, at doses of 0, 200, 600, and 2000 mg/kg/day. There were no GTC-H-related deaths or macroscopic findings. During the entire gestation period in the high-dose (2000 mg/kg/day)-treated group and during days 6–9 and 6–18 in the 600 mg/kg/day group, mean body weight gain was lower. Mean feed consumption was lower during gestation days 6–9 in the 600 mg/kg/day group and during gestation days 6–9 and 9–12 in the 2000 mg/kg/day group. Compared to the control group, mean body weights in the 600 and 2000 mg/kg/day groups were up to 5.1% and 7.7% lower during gestation days 9–20. GTC-H administration did not affect mean gravid uterine weights or intrauterine growth and survival. There were no GTC-H-related fetal malformations or developmental variations. Based on the results of this study, the no-observed-adverse-effect level (NOAEL) for GTC-H was 200 mg/kg/day for maternal toxicity, and 2000 mg/kg/day for embryo/fetal development.  相似文献   

10.
Elephantorrhiza elephantina root extract has been used as a traditional remedy for a wide range of ailments both in humans and livestock. As part of the safety assessment of the extract, acute, sub-acute and chronic toxicity tests were conducted by the oral route in rats. Male and female rats were divided into four groups consisting of five rats each and given doses of 200–1600 mg/kg bwt, 200–800 mg/kg bwt and 50–400 mg/kg bwt in acute (1 day), sub-acute (14 days) and chronic toxicity (35 days), respectively. During the experiment, no deaths were observed in any groups and there were no remarkable changes in general appearance, as well as in food and water consumption. Significant (P < 0.05) changes were however noted in body weights, haematological and serum biochemical parameters between the control and treated groups. Histopathological changes were also noted in kidneys, lungs, liver and spleen of rats receiving high doses. Based on these findings, it can be inferred that the plant has some potential toxicity at certain dose levels; therefore caution has to be taken when using E. elephantina for medicinal purposes.  相似文献   

11.
Forty eight male Balb/c mice, each weighing 30–35 g, were used in the present study. The animals were divided into four equal groups. The first group served as the control group, and the second group was administered royal jelly at a dose of 50 mg/kg bw by gavage for a period of 7 days. The third group received 200 ppm fluoride, as sodium fluoride, for a period of 7 days, in drinking water. Lastly, the fourth group was given 200 ppm fluoride in drinking water, in association with royal jelly at a dose of 50 mg/kg bw by gavage, for a period of 7 days. At the end of the seventh day, blood samples were collected from all groups into heparinised and dry tubes, and liver samples were taken concurrently. Erythrocyte and liver tissue malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were evaluated in the blood and tissue samples obtained. Furthermore, serum cholesterol, triglyceride, glucose, total protein and albumin levels, and aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alcaline phosphatase (ALP) activities were evaluated. In conclusion, fluoride was determined to cause adverse effects in mice, and the administration of royal jelly to these animals alleviated the adverse effects of fluoride.  相似文献   

12.
Potatoes are a source of glycoalkaloids (GAs) represented primarily by α-solanine and α-chaconine (about 95%). Content of GAs in tubers is usually 10–100 mg/kg and maximum levels do not exceed 200 mg/kg. GAs can be hazardous for human health. Poisoning involve gastrointestinal ailments and neurological symptoms. A single intake of >1–3 mg/kg b.w. is considered a critical effect dose (CED). Probabilistic modelling of acute and chronic (usual) exposure to GAs was performed in the Czech Republic, Sweden and The Netherlands. National databases on individual consumption of foods, data on concentration of GAs in tubers (439 Czech and Swedish results) and processing factors were used for modelling. Results concluded that potatoes currently available at the European market may lead to acute intakes >1 mg GAs/kg b.w./day for upper tail of the intake distribution (0.01% of population) in all three countries. 50 mg GAs/kg raw unpeeled tubers ensures that at least 99.99% of the population does not exceed the CED. Estimated chronic (usual) intake in participating countries was 0.25, 0.29 and 0.56 mg/kg b.w./day (97.5% upper confidence limit). It remains unclear if the incidence of GAs poisoning is underreported or if assumptions are the worst case for extremely sensitive persons.  相似文献   

13.
Evidence suggests that the purported health benefits associated with green tea consumption are related to tea catechins. In the present study, potential adverse effects of a standardized heat-sterilized green tea catechin (GTC-H) preparation was investigated following gavage administration to rats at doses of 0, 120, 400, 1200 mg/kg/day for 6 months. A decaffeinated high-dose group (1200 mg/kg/day) (GTC–HDC), was included for comparison. A possibly test article-related clinical finding of intermittent increased activity was noted in the 400 and 1200 mg/kg/day GTC-H groups, but was not considered to be adverse. Lower body weight gains without any decrease in food consumption were noted in the high-dose (1200 mg/kg/day)-treated GTC-H and GTC–HDC females. In the high-dose male GTC-H group, a lower total motor activity count for the 60-min session was noted prior to dosing at the study week 25 evaluations compared to the control group. Similar changes were not observed in the GTC–HDC group. Based on the results of this study, the no-observed-adverse-effect level (NOAEL) for GTC-H was 1200 mg/kg/day for males, the highest dose tested, and 400 mg/kg/day for females based on reduced body weight gains. The NOAEL for GTC–HDC was 1200 mg/kg/day for males and could not be determined in females.  相似文献   

14.
The aim of the study was the use of a fast and simple method using ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC–MS/MS) for the simultaneous determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2), deoxynivalenol (DON), T2 and HT2 toxins in 58 samples of raw wheat (n = 34), barley (n = 5), sorghum (n = 3), processed wheat (n = 13) and breakfast cereals (n = 3) from Tunisian markets. The frequency of contamination of total samples with the analyzed mycotoxins was 50%. AFG2 was the most frequently detected in 11 samples (4 wheat, 4 barley and 3 sorghum) and it was detected at 5.2–52.4 μg/kg. HT2 toxin contaminated seven samples (4 wheat and 3 barley) and it was detected at 5.0–11.1 μg/kg. FB2 was detected in one wheat, sorghum, semolina and breakfast cereal samples at 5.0–61.5 μg/kg. FB1 was detected in three samples (2 sorghum and one barley) at 6.4–120 μg/kg. AFB1 was only found in two sorghum samples at 14 and 79.9 μg/kg. OTA was detected in one sorghum sample at concentrations below limit of quantification (5 μg/kg). The analytical results also showed that all the analyzed samples were not contaminated with DON, AFG1, AFB2 and T2 toxin.  相似文献   

15.
The aim of the present study was to characterize the preclinical pharmacokinetics, tissue distribution and excretion profiles of porcine fibrinogen in rats after intraperitoneal injection of a porcine-derived fibrin glue. A sensitive and rapid isotope-labeled assay method was developed and validated for quantitative analysis in biological analysis. Porcine fibrinogen, the major composition of the fibrin glue, was radioiodinated with Na125I using the Iodo-Gen method. Following the purification and identification of 125I-porcine fibrinogen, the fibrin glue containing 125I-porcine fibrinogen was intraperitoneally administered to rats at three single dosages (100, 200, 400 mg/kg of porcine fibrinogen). The results showed that the 125I-labeled assay method was suitable for the quantification of porcine fibrinogen in plasma samples, tissue samples and excreta samples with satisfactory linear (r2 > 0.998), precision (<13%), accuracy (95.9–104.2%) and recovery (>85%). After three single administrations, plasma concentration profiles showed a slow absorption phase with the mean tmax of 1.83–5.67 h and a slow elimination proceeding with the terminal elimination half-life (T1/2) of 84.5–96.3 h. Porcine fibrinogen was widely distributed to most of the tissues examined after a single intraperitoneal administration at 200 mg/kg to rats. The radioactive porcine fibrinogen showed substantial disposition in liver, kidneys, stomach and intestine. Approximately 79.3% and 17.2% of administered radioactivity were recovered in urine and feces within 528 h post-dosing, which indicated the major elimination route was urinary excretion.  相似文献   

16.
A rapid and simple method of high performance liquid chromatography with UV detection for the quantification of bis(12)-hupyridone in rat blood has been developed and validated. Chromatographic separation was carried out in an Agilent Extend C18 5 μm column (length, 250 mm; inner diameter, 4.6 mm) using a mixture of water–acetonitrile–trifluoroacetic acid (81:19:0.04, v/v/v) as the mobile phase at a flow rate of 1 mL/min, with detection at 229 nm. The method used for the bis(12)-hupyridone quantification showed linearity for concentration range of 0.1–7.5 μg/mL with r2 = 0.9991. The limit of detection and quantification of this method were 0.05 μg/mL and 0.1 μg/mL, respectively. The intra- and inter-day variations of the analysis were less than 4.22% with standard errors less than 13.3%. The developed method was successfully applied to the pharmacokinetic study of bis(12)-hupyridone after intravenous administration of 5 mg/kg and intraperitoneal administration of 10 and 20 mg/kg in rats.  相似文献   

17.
A sensitive method for the quantification of oxaceprol in rat plasma using high-performance liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed. Sample pretreatment involved a simple protein precipitation by the addition of 60 μL of acetonitrile–methanol (1:2, v/v) to 20 μL plasma sample volume. Separation was achieved on a Dikma ODS-C18 (5 μm, 150 mm × 4.6 mm) reversed-phase column at 40 °C with acetonitrile/0.1% formic acid–4 mM ammonium acetate in water (35:65,v/v) at a flow rate of 0.6 mL/min. Detection was performed using an electrospray ionization (ESI) operating in negative ion multiple reaction monitoring (MRM) mode by monitoring the ion transitions from m/z 172 → 130 (oxaceprol) and m/z 153 → 109 (protocatechuic acid, internal standard). The calibration curve of oxaceprol in plasma showed good linearity over the concentration range of 1.25–800 ng/mL. The limit of detection and limit of quantification were 0.400 ng/mL and 1.25 ng/mL, respectively. Intra- and inter-day precisions in all samples were within 15%. There was no matrix effect. The validated method was successfully applied to a preclinical pharmacokinetic study of oxaceprol in rats. After oral administration of 20 mg/kg oxaceprol to rats, the main pharmacokinetic parameters Tmax, Cmax, T1/2, Vz/F and AUC0–t were 1.4 h, 1.2 μg/mL, 2.3 h, 19.7 L/kg and 3.4 mg h/L, respectively.  相似文献   

18.
In order to assess the risk of patients being exposed to an anti-AIDS medication contaminated with EMS we have performed in depth genotoxicity, general toxicity and DMPK investigations. The results of these studies are reported in the accompanying papers of this issue. Prior to starting our investigations we searched the literature for toxicity data on this well established mutagen with specific attention to dose–response relations in in vivo genotoxicity studies, since, obviously, in vivo data are pivotal for risk assessment. There are numerous published in vivo genotoxicity studies on EMS, with generally 50 mg/kg – or higher – being the minimal dose used. The dose of 50 mg/kg induced effects in some, but not all studies, while the dose of 100 mg/kg was clearly positive in most studies, except for heritable mutations where a single dose of 100 mg/kg was not observed to induce measurable effects in post-meiotic stages and even the maximal dose of 250 mg/kg was negative in pre-meiotic stages of male germ cell development. For somatic cells, NOEL values could not be derived for any of the endpoints studied. Although a large number of genotoxicity studies are available, none of the studies was sufficiently detailed to allow unambiguous conclusions about the presence of a (practical) threshold. But in most cases the dose–responses show a sublinear relationship (i.e. the slope increases with dose) which indicates that the data would not be incompatible with a threshold dose–response relationship. This stands in contrast to data on ethylnitrosourea (ENU) which has been studied concommittantly with EMS in several in vitro and in vivo genotoxicity investigations. ENU generally appeared to induce genotoxic effects with linear dose relationships.  相似文献   

19.
Chickens were used to investigate plasma disposition of chlortetracycline after single IV (15 mg/kg) and multiple oral administration (60 mg/kg, 5 days) and residue depletion of chlortetracycline after multiple oral doses (60 mg/kg, 5 days). Plasma and tissue samples were analyzed by HPLC. Mean elimination half-lives in plasma were 7.96 and 13.15 h after IV and multiple oral administration. Maximum plasma concentration was 4.33 μg/ml and the interval from oral administration until maximal concentration was 1.79 h. Oral bioavailability was 17.76%. After multiple oral dose, mean kidney, liver and muscle tissue concentrations of chlortetracycline + 4-epi-chlortetracycline of 835.3, 192.7, and 126.3 μg/kg, respectively, were measured 1 day after administration of the final dose of chlortetracycline. Chlortetracycline residues were detected in kidney and liver (205.4 and 81.7 μg/kg, respectively), but not in muscle, 3 days after the end of chlortetracycline treatment. The mean chlortetracycline + 4-epi-chlortetracycline concentrations were below LOQ at 3 and 5 days after cessation of medication in muscle and liver, respectively. A withdrawal time of 3 days was necessary to ensure that the chlortetracycline residues were less than the maximal residue limits (MRLs) established by the European Union (100, 300, and 600 μg/kg in muscle, liver, and kidney, respectively).  相似文献   

20.
The tolerable level of dietary quercetin for exerting its antioxidative effect was evaluated in high cholesterol-fed rats, using quercetin-containing diets (31–1260 mg quercetin/kg body weight/day) and onion diets (19–94 mg quercetin aglycone equivalent/kg body weight/day), from the viewpoint of a safety assessment. After feeding for 4 weeks, the urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) levels of the quercetin-containing diet groups fed more than 157 mg quercetin/kg body weight/day were higher than the group fed a quercetin-free diet, although the plasma quercetin metabolite levels and plasma antioxidative activity were elevated depending on the amounts of quercetin or onion diet intake. No significant effect on body weight gain by quercetin-containing diets or onion diets was observed. However, ratios of the liver and kidney weights to the body weight were significantly increased in the quercetin-containing diet groups fed more than 314 mg and 157 mg quercetin/kg body weight/day, respectively, and in the onion diet groups fed more than 47 mg quercetin aglycone equivalent/kg body weight/day. These results indicated that the tolerable level for dietary quercetin for exerting its antioxidative effect was between 126 and 157 mg/kg/day for the quercetin diet and between 19 and 34 mg/kg/day for the onion diet.  相似文献   

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