Acute toxicity and histopathology study of a galactose-specific lectin from the seeds of Tetracarpidium conophorum (African walnut) (Hutch and Dalz)

A lactose-binding lectin (TCL) was purified from the seeds of African walnut, Tetracarpidium conophorum, and acute toxicity studies of the lectin were carried out with Swiss albino male mice. Animals were administered doses of TCL from 500 to 2500?mg?kg^?1 body weight (b.wt.) orally while intraperitoneally the dose ranged from 10 to 600?mg?kg^?1 b.wt. Animals were then assessed for organ and body weight changes, mortality, and histopathology. TCL did not cause any observable toxicity via the oral route; however, when administered intraperitoneally, TCL elicited toxicity with an LD₅₀ of 50?mg?kg^?1 b.wt. Death from intoxication was preceded by convulsion, hypoactivity, salivation, ataxia, and weakness. The animals given lethal doses of the lectin showed profound respiratory depression which was judged to be the primary cause of death. Histopathological analysis indicated that the lungs, liver, and spleen were adversely affected while the kidney and other organs were essentially normal. In all the affected organs, the severity of toxicity was dose-dependent as the effect of the lectin became more pronounced with increase of the dose administered.     

The effects of bisphenol A on sex hormone levels of F0 female rats and F1 male rats during weaning period

The effects of bisphenol A (BPA) were examined on sex hormones of F1 generation male rats during weaning period. Female rats were exposed to BPA from day 0 after pregnancy to the weaning period at doses of 50, 100, or 200 mg kg^?1. The sex hormone levels of F1 generation male rats were determined. This study shows that F0 generation female rats fed with 200 mg kg^?1 BPA had a significantly higher serum prolactin (PRL) levels at the end of weaning. Significantly higher levels of serum estradiol (E₂) were also found in female rats fed 100 or 200 mg kg^?1 BPA. Serum levels of E₂ in F1 male generation rats were higher in treatment groups compared to control groups while serum testosterone (T) levels were lower. Follicle stimulating hormone (FSH) in F1 generation rats fed 200 mg kg^?1 was markedly decreased. The relative testicular weights were significantly less in 100 and 200 mg kg^?1 BPA groups. BPA was found to alter the sex hormone levels in F1 male rats during weaning period and thus disrupted endocrine functions.     

Chlorpyrifos induces oxidative stress in rats

This study was carried out in male Wistar rats to determine the potential effects of chlorpyrifos (CHP) on oxidative stress, as was reported for organophosphorus (OP) pesticides. Following an acute, daily 3- or 14-day exposure with CHP at doses of 2.5, 5, or 25 mg kg^?1 data showed significant increases in malondialdehyde levels at both exposure durations and at all doses, except for 2.5 mg kg^?1, in hepatic and aorta, kidney, and plasma samples. The nitrites (NO) showed elevation at 25 mg kg^?1 in aorta, at 3- and 14-day exposure, in hepatic tissue with all doses at 3-day exposure, but not at 14-day with a 5 mg kg^?1 dose. In plasma, increases occurred only at 25 mg kg^?1 at both exposure times, and in kidney at all doses and both exposure durations. Superoxide dismutase (SOD) enzyme activity in the aorta sample was statistically significant at all doses at 3 days and at 14 days, except at 2.5 mg kg^?1; and in hepatic tissue only at 25 mg kg^?1 dose at both durations. In plasma SOD activity was elevated at all doses at 3 days, but at 14 days only at 25 mg kg^?1. Data suggests that oxidative stress may be involved in the effects of CHP on rats.     

Protective effects of α-lipoic acid and chondroitin-4-sulfate against benomyl-induced toxicity in rats

In this study, the effects of fungicide benomyl and the protective effects of α-lipoic acid (LA) and chondroitin-4-sulfate (C4S) used as antioxidants on liver and kidney of rats were investigated. Benomyl (200 mg kg^?1), LA (200 mg kg^?1), and C4S (25 mg kg^?1) were administered intraperitoneally by injection once a week for a period of five weeks. The results of this study are as follows: benomyl given subchronically showed toxic effects in the form of lipid peroxidation (LPO) on liver and kidney, and LA and C4S had antioxidant effects on liver and kidney. When LA and C4S were applied together, they were more effective than individually. Furthermore, it was observed that LA and C4S had partial protective effects against the histopathological effects caused by benomyl.     

Essential and nonessential elements in the red-crowned crane Grus japonensis of Zhalong Wetland,northeastern China

The concentrations of four essential (Ca, Mg, Zn, and Cu) and two nonessential elements (Pb and Cd) in feathers and kidneys, livers, gut walls, and muscles of eight carcasses of migratory red-crowned cranes (Grus japonensis) from Zhalong Wetland, northeastern China, were examined. The concentrations of Cd in the feathers were between 0.4 mg kg^?1 dry weight (dw) and 3.1 mg kg^?1 dw, in the livers between 0.4 and 4.4 mg kg^?1 dw, the maximum of which exceeded a level considered to be environmental exposure risk (i.e., 3 mg kg^?1 dw in the liver or kidney). High Pb levels (0.4–3.2 mg kg^?1 dw, with an average of 1.8 mg kg^?1) were also detected in livers, which exceeded a level considered toxicosis in birds (1.7 mg kg^?1 dw). Pb and Cd had the highest scores in principal component analysis. Relatively high Pb and Cd concentrations in the migratory cranes were thought to be associated with their habitat and prey.     

Sensorimotor performance deficits induced by chronic chlorpyrifos exposure in Wistar rats: mitigative effect of vitamin C

This study was aimed at evaluating the ameliorative effect of vitamin C on chlorpyrifos-induced sensorimotor changes involving postural reflex, limb placing, and vibrissae touch in Wistar rats. Forty adult Wistar rats of either sex were divided into 4 groups of 10 animals in each group. Group I was administered soya oil (2?mL?kg^?1) while group II was given vitamin C (100?mg?kg^?1); group III was dosed with chlorpyrifos (10.6?mg?kg^?1, i.e. ～1/8th of the LD₅₀); group IV was administered vitamin C (100?mg?kg^?1) and then exposed to chlorpyrifos (10.6?mg?kg^?1), 30?min later. The regimens were administered by gavage once daily for a period of 17 weeks. Neurobehavioral parameters involving postural reflex, limb placing, and vibrissae touch responses measured at various intervals revealed a deficit in postural reflex, limb placing, and vibrissae touch responses in the CPF group, which was mitigated by vitamin C pretreatment. The neuronal and glial cell degeneration, increased brain malonaldehyde concentration, and decrease in superoxide dismutase, catalase, and acetylcholinesterase activities recorded in the group given chlorpyrifos were ameliorated by vitamin C. Therefore, vitamin C was shown to mitigate chlorpyrifos-induced sensorimotor deficits partly due to its antioxidant and acetylcholinesterase restoration properties.     

Toxicological studies of zinc oxide nanomaterials in rats

In this study, we have evaluated the ability of zinc oxide (ZnO) nanoparticles to induce pulmonary and extrapulmonary toxicities was examined in rats following intratracheal (IT) instillation. Lungs of rats were instilled IT with either phosphate-buffered saline (PBS)?+?1% Tween 80, ZnO nanoparticles, carbonyl iron or quartz particles at a dose of 1 or 5?mg?kg^?1 body weight. Following exposure, bronchoalveolar lavage (BAL) fluid, blood samples and organs including lung, liver, kidneys, heart, pancreas, and brain were collected at 24?h, 1 week, or 1 month of post instillation of nanoparticles and different parameters estimated to assess toxicity. BAL fluid was analyzed for lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) to assess pulmonary toxicity. Exposures to ZnO or quartz particles produced transient dose-dependant increase in BAL fluid LDH and ALP activities at all post exposure periods. Blood samples were analyzed for the tissue damage biomarkers to assess extrapulmonary toxicity. Histopathological examination of lung, liver and kidneys revealed dose-dependent degeneration and necrosis which worsened at 1 week post-instillation periods but recovered at 1 month post instillation. Histopathological examination of rat pancreas, heart, and brain exposed to quartz or ZnO particles showed no marked changes. Data suggest the instillation of ZnO nanoparticles produced a greater pulmonary toxicity in rats comparable with quartz; and extrapulmonary toxicities of these ZnO nanoparticles might be due to translocation into liver and kidney.     

Effects of Matricaria chamomilla L. on lipid peroxidation,antioxidant enzyme systems,and key liver enzymes in CCl4-treated rats

In this study, we investigated the effects of Matricaria chamomilla L. extract (MCE) on lipid peroxidation, antioxidant enzyme systems, and several liver enzymes in carbon tetrachloride (CCl₄)-treated rats. Rats were divided into five groups. The first group (control group) was fed on standard feed. The rats in the other groups (CCl₄, MCE50, MCE100, and MCE200) were injected intraperitoneally with 0.8?mL?kg^?1 CCl₄. Moreover, rats in the MCE50, MCE100, and MCE200 groups were gavaged with 50?mg?kg^?1, 100?mg?kg^?1, and 200?mg?kg^?1 MCE, respectively. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, whole blood malondialdehyde (MDA) and glutathione (GSH) levels, and erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activity levels were measured after 14 days of exposure. ALT and AST in the CCl₄ group increased significantly in comparison to the control group (p?4, MCE50, MCE100, and MCE200 groups at different significance levels. In conclusion, the findings suggest that, depending on the dose administered, MCE decreases CCl₄-induced damage and consequent oxidative stress in rats; it affects the antioxidant system positively.     

Bromobenzene-induced hepatotoxicity in male rats: the protective effect of flaxseed

The metabolites of bromobenzene (BB) are hepatotoxic. The aim of this study was to determine the efficacy of different doses of flaxseed extract in alleviating BB-hepatotoxicity in male albino rats. Oxidative stress parameters, drug metabolizing enzymes, a pro-inflammatory marker, an apoptotic marker, and DNA fragmentation pattern were also assessed. Animals were divided into five groups treated by intragastric intubation as follows: control, BB-treated 460?mg?kg^?1?BW alone; three animal groups (III, IV, V) were treated concurrently with 460?mg?kg^?1 BB daily for 3 weeks and different doses of flaxseeds extract: 100, 200, or 300?mg?kg^?1?BW. Oral treatment of BB produced a significant decrease in activities of antioxidant enzymes superoxide dismutase and glutathione peroxidase and glutathione levels, while activities of glutathione reductase and drug-metabolizing enzymes; glutathione-S-transferases and cytochrome P450 were enhanced. BB-treatment resulted in enhanced production of nitric oxide and activation of COX-2 and caspase-3. Pre-treatment with different doses of flaxseeds extract prior and during BB-treatment protected liver against BB-induced hepatotoxicity. The lower dose of flaxseed extract (100?mg?kg^?1) was most effective one.     

Toxicokinetics,metabolism, and microsomal studies of chlorpropham in rats

A study on the toxicokinetic behavior, metabolism of chlorpropham, and its effect on cytochrome P₄₅₀ from liver microsomes was carried out in albino rats after a single and consecutive oral administration at 500?mg?kg^?1 body weight for 10 and 20 days. Chlorpropham was detected in the blood at 0.08?h (11.43?±?1.72?µg?mL^?1) reaching a maximum concentration at 2?h (30.90?±?2.55?µg?mL^?1) and a minimum at 48?h (1.95?±?0.20?µg?mL^?1) after a single oral administration of 500?mg?kg^?1. The absorption rate constant (K _a) was 0.66?±?0.48?h^?1. The Vd _area (18.01?±?2.78?L?kg^?1) and t _1/2 β (12.23?±?1.96?h) values suggested a wide distribution and long persistence of the compound in the body, respectively. The higher Cl_R (0.82?±?0.00?L?kg^?1?h^?1) compared to Cl_H (0.18?±?0.02?L?kg^?1?h^?1) value indicated that a major portion of chlorpropham was excreted through the urine (30%) compared to the faeces (2.81%). Chlorpropham residue was detected in all tissues of rat at 0.25?h while its metabolite, meta-chloroaniline was detected in liver, kidney, heart, lung, and spleen tissue at 0.25?h. Meta-chloroaniline was not detected in skeletal muscle, brain, fat, and stomach tissue at any time of the observation period. Maximum concentrations of chlorpropham and meta-chloroaniline were detected at 2?h (except in the spleen), and minimum concentrations of chlorpropham at 24 (heart, lung, spleen, skeletal muscle, and stomach) and 48?h (liver, kidney, brain, and fat tissue) respectively; and meta-chloroaniline at 24?h (except heart and spleen). The tissue half-life of chlorpropham in rat varied from 3.80 to 11.60?h. Repeated oral administration of chlorpropham at 500?mg?kg^?1 for 10 and 20 days caused an induction of the liver microsomal pellet of rat.     

Potential hepatoprotective effects of vitamin E and Nigella sativa oil on hepatotoxicity induced by chronic exposure to malathion in human and male albino rats

Malathion is an organophosphorus (OP) insecticide and has a wide range of use in agriculture, veterinary medicine, and public health. Malathion and other OP insecticides produce hepatotoxic effects. The objective of the present study was to investigate the protective effects of Nigella sativa oil and α-tocopherol (vitamin E) on the hepatotoxicity induced by malathion on workers involved in the formulation of pesticides, chronically exposed to malathion, and in male albino rats orally administrated malathion. This study was conducted on both human and experimental animals, the human study was conducted on 30 control subjects working as administrators and 45 subjects working in formulation of pesticides and exposed to malathion (≥3 years), all were males with age ranges from 30 to 60 years. The 45 males working in pesticides formulation were classified into three groups; (1) 15 workers exposed to pesticides (2) 15 workers exposed to pesticides and received vitamin (E), in a dose of 10 mg kg?1 day^?1 orally for 60 days, and (3) 15 workers exposed to pesticides and received 100 mg kg^?1 day^?1 of N. sativa oil for 60 days. The animal experiment was conducted on 40 adult male albino rats weighing 150–200 g. They were divided into four groups (10 rats in each group). First group served as the control group, the second group received malathion in a dose of 50 mg kg^?1 orally per day for 60 days, the third group received malathion (in the same dose and route of administration) and vitamin E in a dose of 10 mg kg^?1 day^?1 orally for 60 days, and the fourth group received malathion (in the same dose and route of administration) and N. sativa oil in a dose of 100 mg kg^?1 day^?1 orally for 60 days. Liver function tests (alanine aminotransferase [ALT], aspartate aminotransferase [AST], serum alkaline phosphatase [ALP], albumin, globulin, albumin/globulin ratio, and total proteins), antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD), and total glutathione peroxidase (GPx)), and lipid peroxidation [MDA] were analyzed in both human and animal experiments. The results of both human and animal study revealed that, exposure to malathion produced significant increases in AST, ALT, and lipid peroxidation. There were significant decrease in albumin, albumin/globulin ratio, total protein, and antioxidant enzymes. There was no significant change in ALP. In addition exposed workers showed significant decreases in serum globulin. Nigella sativa oil or vitamin E administration showed significant improvement of liver function tests, lipid peroxidation, and antioxidant enzymes impairment induced by malathion. Thus, dietary supplement, N. sativa oil, or vitamin E may represent a potential therapeutic agent in reducing malathion-induced hepatotoxicity.     

内质网应激在PFOS致大鼠肝损伤中的作用

通过全氟辛烷磺酸(PFOS)28 d大鼠经口染毒评价PFOS肝损伤效应,探讨内质网应激在PFOS毒效应中的作用。Wistar大鼠随机分组,分别以0 mg·kg~(-1)、5 mg·kg~(-1)和10 mg·kg~(-1)PFOS灌胃染毒28 d。HE染色观察大鼠肝脏形态改变。ELISA法测定各组丙氨酸转氨酶(ALT)、天门冬氨酸转氨酶(AST)、碱性磷酸酶(ALP)和淀粉酶(AMY)含量变化。紫外分光光度法测定肝组织匀浆中丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性变化。RT-PCR检测肝脏内质网应激标志蛋白表达水平。结果表明,PFOS造成大鼠体重降低、肝重增高(P0.05),组织切片显示肝细胞出现脂质沉积。PFOS不同剂量组大鼠ALT随暴露浓度增加,分别为(50.96±10.02)U·L~(-1)、(71.73±11.55)U·L~(-1),显著高于对照组(P0.05),AST、ALP含量与对照组相比显著上升(P0.05),高剂量组AMY水平为(833.46±63.05)U·L~(-1),与对照组相比显著降低(P0.05)。GSH-Px和SOD水平随PFOS浓度增加出现了显著降低(P0.05),而MDA水平显著升高(P0.05)。内质网应激标志蛋白表达均较对照组显著上升(P0.05)。以上结果说明PFOS可导致大鼠肝细胞损伤,其机制可能与内质网应激调控有关。     

Protective efficacy of Mucuna pruriens extract on Epichlorohydrin induced toxicity in epididymis of albino rats

The protective effects of seeds of Mucuna pruriens on epichlorohydrin (ECH)-induced toxicity in epididymis and epididymal sperms of rats were studied. Different doses of ECH and M. pruriens (75 and 100 mg kg^?1, respectively) were administered daily, orally for 70 days. Group I animals served as control. Group II and III rats received ECH (75 or 100 mg kg^?1 body weight, respectively) alone. The group IV and V rats received a combination of both ECH and the seed extract of M. pruriens at 75 or 100 mg kg^?1 body weight. Group VI rats was administered only the extract of M. pruriens 100 mg kg^?1 body weight. At the end of the experiment (71st day), rats were sacrificed and sperm collected from epididymis were used for the assessment of sperm count, sperm viability, and sperm motility. Administration of ECH produced a reduction in epididymal sperm count, sperm viability, and sperm motility. The activities of catalase, superoxide dismutase, and glutathione peroxidase were decreased, while lipid peroxidation was increased. ECH produced a decrease in the levels of protein, acid phosphatase, sialic acids, and increased the level of alkaline phosphatase, and cholesterol. The administration of M. pruriens to ECH-treated rats resulted in a protective effect.     

Protective effects of Flacourtia indica on doxorubicin-induced cardiotoxicity in rats

This study examined the cardioprotective activity of an ethanolic extract of Flacourtia indica (FI) against doxorubicin (DOX)-induced myocardial infarction (MI) in rats. Different phytoconstituents were identified by gas chromatography-mass spectroscopy. DOX is a chemotherapeutic agent which produces free oxygen radicals that result in serious dose-limiting cardiotoxicity. A DOX dose of 20?mg?kg^?1 body weight is used to bring significant changes in biochemical parameters, endogenous antioxidants, and moderate necrosis in the heart. The pretreatment with FI at two doses (250 and 500?mg?kg^?1) to DOX-treated rats significantly prevented the altered biochemical parameters such as serum marker enzymes serum glutamate-pyruvate transaminase, serum glutamate oxaloacetate transaminase, creatine phosphokinase, and lactate dehydrogenase, lipid profile such as low-density lipoprotein, very low-density lipoprotein, triglycerides, high-density lipoprotein, total cholesterol, and antioxidant parameters such as superoxide dismutase, glutathione, catalase, glutathione peroxidase, and malondialdehyde to near normal level. Serum urea, uric acid, and alkaline phosphate which are increased on DOX administration registered near normal values on pretreatment with FI. In conclusion, these data suggest that the ethanol extract of FI can prevent heart damage by DOX-induced MI in rats and this is likely mediated through its antioxidant activities.     

Arsenic content and distribution pattern in Chinese coals

About 500 samples of coal, pyritic coal balls, pyritic gangue and coal seam gangue were collected from different coal basins and geologic periods of coal formation to determine the arsenic (As) content and distribution pattern in China. The Permian-Carboniferous and Jurassic coals in the North China Plate and Northwest China account for nearly 85% of total Chinese coal reserves and data showed that As content ranged from 0.1 to 94?mg?kg^?1, with the majority between 1 and 14.9?mg?kg^?1. The As content of some Late Permian coals in Southwest Guizhou Province and stone coal in the South Qinling Mountain area were exceedingly high (30–534?mg?kg^?1), but the majority of coal in the Southwest Guizhou Province contained low to medium amounts. Only the coals, which are situated in or near igneous rocks and are not considered a part of Chinese coal reserves, possessed unusually high As content (>30?mg?kg^?1). Arsenic was also concentrated in pyritic coal balls and the pyritic gangue of the coal seam with values ranging from 21.5 to 142.46?mg?kg^?1 and an average of 69?mg?kg^?1 in Shaanxi and 78?mg?kg^?1 in Shandong. Arsenic contents in coal gangue in the Northwest and North China Plate is about 0.2–15?mg?kg^?1, a little lower than coals in the same seam. Washing gangue (waste from coal washing) generally contained more As than coal, because the washed gangue has more pyrite than the natural gangue (black shale). Washing coal reduced the content of the pyritic sulfur, heavy metals and As. Based on amounts of coal used with different As content in Chinese coal reserves, the average As content of Chinese coals is about 4.5?mg?kg^?1.     

Determination of metals in printed wiring boards of waste mobile phones

Metal contents of waste mobile phones represent a major environmental risk, especially considering the adoption of inappropriate management options in developing countries including open burning and disposal into surface water bodies. In this study the metal contents of mobile phone printed wiring board (PWB) samples were assessed. Sixty-two waste mobile phones of 15 brands were collected, dismantled, and their PWB samples were analyzed for Cu, Pb, Ag and Cd. The metal concentrations in the samples varied widely between and within brands. Among these metals, Cu and Pb were found to be at very high concentrations. The range (mean?±?SD) of Cu and Pb concentrations were 94.1–532?g?kg^?1 (250?±?92.3?g?kg^?1) and 7.0–46.2?g?kg^?1 (20.1?±?8.4?g?kg^?1), respectively. All Cu and Pb concentrations exceeded toxicity threshold limit concentration (TTLC) regulatory limits used in characterizing wastes as hazardous in the state of California, USA. The mean Cu and Pb concentrations exceeded the corresponding TTLC limits by factors of 100 and 20, respectively. The Ag and Cd concentrations were in the range 59.4–759?mg?kg^?1 (mean 227?±?104?mg?kg^?1) and ND – 15.6?mg?kg^?1 (2.1?±?3.3?mg?kg^?1), respectively.     

Persistence of chlorpyriphos in okra (Abelmoschus Esculentus) fruits and soil

Persistence of cypermethrin and chlorpyriphos in okra and soil were studied following the application of pre-mix formulation of insecticides Action 505EC (chlorpyriphos 50%?+?cypermethrin 5%) at single (275?g a.i.?ha^?1) and double dose (550?g a.i.?ha^?1). The average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg^?1 in single and double dose, respectively, which dissipated to 92% after 10 days for both the dosages. Residues of soil under okra crop were found to be 0.15?mg?kg^?1 at the single and 0.36?mg?kg^?1 at the double doses. These residues persisted up to 3 days at single and 5 days at double dose. The half-life (t _1/2) periods of chlorpyriphos on okra and soil were observed to be 0.6 days and 1.9 days for single and double dose, respectively. Residues of chlorpyriphos reached below detectable level (BDL) of 0.01?mg?kg^?1 in okra fruits after 7 days at single dose and in 15 days in double dose. In soil, residues of chlopyriphos persisted up to 5 and 7 days in single and double dose, respectively. Following foliar applications of a insecticide formulation (Action 505EC, (chlorpyriphos 50%?+?cypermethrin 5%) on okra at @ 275 and 550?g active ingredient (a.i.)?ha^?1 resulting in active applications of chlorpyriphos at the rate of 250 and 500?g a.i.?ha^?1 the average initial deposits of chlorpyriphos in okra were observed to be 0.07 and 0.15?mg?kg^?1, respectively. These residue levels dissipated to 92% after 10 days at both the dosages. Residues of soil under the okra crop were found to be 15?mg?kg^?1 at the single and 36?mg?kg^?1 at the double dose. The residues persisted up to 3 days at the single and 5 days at the double dose. The half-life (t _1/2) periods of chlorpyriphos on okra were observed to be 0.6 days for application rates, and 1.9 days for soil. Okra fruits and soil samples collected on the 7th and 15th day after application did not show any chlorpyriphos residues above their determination limits of 0.01 and 0.005?mg?kg^?1, respectively.     

口服纳米银对大鼠的生物有效性及其体内分布的研究

由于独特的抗菌特性，纳米银(AgNP)在诸多领域得到广泛应用，但是其生物有效性、动物组织分布及排出尚不清楚。将聚乙烯吡咯烷酮包被的AgNP溶液按照10 mg kg^-1给雌性SD大鼠灌胃，采用ICP-MS检测SD大鼠组织、粪便及尿液中总银浓度。实验结果表明，AgNP通过小肠吸收后，可以通过血液循环快速分布在肝、肾、脾、肺、脑等靶器官。灌胃后1 h，大鼠各组织中总银浓度达到最大值(肝、肾、脾、肺、脑中银浓度分别为0.29 ± 0.13 mg kg^-1、0.23 ± 0.04 mg kg^-1、0.17 ± 0.05 mg kg^-1、0.11 ± 0.01 mg kg^-1、0.06 ±0.02 mg kg^-1)，之后银浓度随时间降低直至和对照组无显著性差异。在灌胃途径下，AgNP对SD大鼠的有效性为8.5%，且73%的AgNP是通过粪便的途径排出体外。     

Nitrate levels in fresh vegetables and berries from central Japan

Nitrate concentrations in 326 recent vegetables and berries sold in Niigata, located in central Japan, were investigated. Maximum nitrate concentrations of 6600 mg kg^?1 were detected in samples of komatsuna (Brassica campestris var. perviridis) and mizuna (B. campestris L.). Mean concentrations ranged from 4 mg kg^?1(blueberry) to 3500 mg kg^?1 (mizuna). Concentrations in spinach ranged from 10 to 6000 mg kg^?1 (mean 1500 mg kg^?1). Nitrate intake from spinach and Japanese radish (Raphanus sativus) were estimated to be 0.7 and 0.8 mg kg^?1 day^?1, respectively. These values are equivalent to 19% and 23% of the acceptable daily intake (ADI). Nitrate intake at the 90th percentile was estimated to be 1.3 mg kg^?1 day^?1 (35% of the ADI) from spinach and 1.6 mg kg^?1 day^?1 (43% of the ADI) from Japanese radish.     

Effect of calcium and magnesium on copper,cadmium, and some essential elements of Indian major carps Labeo rohita (Hamilton) and Catla catla (Hamilton) treated with copper and cadmium

The effect of calcium and magnesium either singly or in combination on accumulation of cadmium and copper in Labeo rohita (rohu) and Catla catla (catla) was investigated in this study under laboratory conditions. The investigation showed that copper accumulation in rohu exposed to 0.25 mg L^?1 of copper for 14 days reduced from 31.0 ± 0.4 mg kg^?1 at no calcium/magnesium treatment to 3.5 ± 0.2 and 2.2 ± 0.1 mg kg^?1, respectively, at 75 mg L^?1 calcium or magnesium treatment. The copper level in catla exposed to 0.20 mg L^?1 of copper for 14 days reduced from 5.7 ± 0.1 mg kg^?1 at no calcium/magnesium treatment to 3.4 ± 0.2 and 3.3 ± 0.1 mg kg^?1, respectively, at 300 mg L^?1 calcium or magnesium treatment. The cadmium accumulation in rohu exposed to 0.20 mg L^?1 of cadmium for 14 days reduced from 1.7 ± 0.1 mg kg^?1 at no magnesium treatment to 1.4 ± 0.1 mg kg^?1 at 120 mg L^?1 magnesium treatment. The cadmium accumulation in catla exposed to 0.20 mg L^?1 of cadmium for 14 days reduced from 0.8 ± 0.2 mg kg^?1 at no magnesium treatment to 0.6 ± 0.2 mg kg^?1 at 80 mg L^?1 magnesium treatment. Copper and cadmium treatments also reduced some essential microelements of rohu and catla. Both the fishes restored these elements at different levels of calcium and magnesium.