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1.
Diiodomethyl-p-tolylsulfone (DIMPTS) was tested in developmental toxicity (DT) and reproductive toxicity studies. In the rat DT study, DIMPTS was administered at 0, 100, 300 or 1000 mg/kg/day. Maternal toxicity as evidenced by reductions in body weight gain or feed consumption at 1000 and, to a lesser extent, 300 mg/kg/day. The only developmental effect was umbilical hernia at 1000 mg/kg/day; therefore, NOELs for maternal and developmental toxicity were 100 and 300 mg/kg/day, respectively. In the rabbit DT study, NZW rabbits were gavaged with 0, 0.05, 0.5 and 2mg/kg/day DIMPTS. The NOEL for maternal toxicity was 0.5mg/kg/day, based on thyroid weight increase with histopathology. There were no observed developmental effects. In the two-generation study, CD rats were fed 0, 2.5, 10 or 40 mg/kg/day DIMPTS. Increased thyroid weight and histopathology were observed at all doses with associated pituitary findings in males. Reproductive toxicity at 40 mg/kg/day consisted of increased postimplantation loss, decreased gestation survival and two cases of dystocia, while litter size, pup survival/weight were affected at 10 and 40 mg/kg/day. The NOEL for parental toxicity could not be determined, while the NOEL for reproductive toxicity was 2.5mg/kg/day. The maternal thyroid and reproductive effects in this study were consistent with iodine toxicity.  相似文献   

2.
The mode of action (MOA) underpinning the reproductive toxicity of diiodomethyl-p-tolylsulfone (DIMPTS) is excess systemic iodine levels, resulting in hypothyroidism. This MOA evaluation also addresses the potential for toxicity and adverse health outcomes during critical windows of development for different tissues. The data indicate that testicular development in the neonate represents the tissue and life-stage that are most sensitive to iodine toxicity. Life-stage specific dosimetry appears to be a major determinant of this sensitivity, with the neonate being exposed to higher levels of iodine than the fetus during the period of testicular development, in particular Sertoli cell maturation and differentiation. While no reports could be found in the literature linking excess iodine exposure in humans to testicular toxicity, there is evidence that neonates born to mothers with excessive iodine intake do exhibit signs of transient hypothyroidism. Although there are major physiological and temporal differences in testicular development and Sertoli cell replication between the rat and human, it is not inconceivable that continuous long term exposures to excess iodine first from maternal milk and then in the diet through to the onset of puberty could affect testicular development. However, exposures to iodinated substances - such as DIMPTS - contribute less than 1% of the required daily iodine intake for normal fetal and neonatal development and, consequently, continuous exposure to excess iodine during the pre-pubertal period is unlikely. As exposures to DIMPTS are both very low and sporadic in nature it is not likely that they represent any risk to health at any life-stage.  相似文献   

3.
Metabolism of diiodomethyl-p-tolylsulfone (DIMPTS) was investigated in rats to determine the role of iodide in its toxicity. Fischer 344 (F-344) (5 or 50 mg/kg) or Sprague Dawley (SD) (5 mg/kg) rats were gavaged with 14C-DIMPTS or dermally applied with 5 mg/kg (F-344 only) and absorption, distribution, metabolism and excretion (ADME) determined. Additional experiments were conducted with its deiodinated analog (methyl-p-tolylsulfone, MPTS) in female F-344 rats (20 mg/kg) for comparison. Orally administered 14C-DIMPTS was rapidly absorbed and eliminated in urine (92%). The elimination t½ was 1–4 h. Dermally applied 14C-DIMPTS remained undetectable in plasma with bioavailability ∼7%, only 5–7% of the dose was recovered in urine. DIMPTS liberated one or both of its iodine atoms upon absorption. The rate of elimination of the liberated iodide from the systemic circulation was 2- to 3-fold slower in SD than F-344 rats, which resulted in higher bioavailability of iodide to SD rats. DIMPTS was primarily oxidized at the benzylic methyl moiety forming the corresponding benzoic acid. Glutathione conjugation on the sulfonyl methyl group, via displacement of I was also observed. Overall 67–80% of the total iodine atoms were metabolically released from DIMPTS. The MPTS was rapidly absorbed from the GI tract, metabolized and eliminated in urine similar to that of DIMPTS. These data were compared to iodide toxicokinetic results of a reproductive toxicity study for DIMPTS (80 mg/kg/day) and MPTS (32 mg/kg/day), where DIMPTS was toxic to dams and pups, while MPTS caused no toxicity. These data show that the liberated iodide is the ultimate toxicant of DIMPTS, which is readily transported to pups through milk, while the methyltolylsulfone backbone structure (MPTS) of DIMPTS is relatively nontoxic.  相似文献   

4.
Extracts of Citrus aurantium L. (Rutaceae) unripe fruits have gained popularity for the treatment of obesity. Due to the wide use of C. aurantium/p-synephrine-containing products, this research was undertaken to evaluate its subchronic toxicity in mice and their actions in oxidative stress biomarkers. Groups of 9–10 mice received for 28 consecutive days a commercial C. aurantium dried extract (containing 7.5% p-synephrine) 400, 2000 or 4000 mg/kg and p-synephrine 30 or 300 mg/kg by oral gavage. There was a reduction in body weight gain of animals treated with both doses of p-synephrine. Organs relative weight, biochemical and hematological parameters were not altered in all treated mice. There was an increase in reduced glutathione (GSH) concentration in groups treated with C. aurantium 4000 mg/kg and p-synephrine 30 and 300 mg/kg. In glutathione peroxidase (GPx), there were an inhibition of the activity in C. aurantium 400 and 2000 mg/kg and p-synephrine 30 and 300 mg/kg treated animals, respectively, and was no alteration in malondialdehyde (MDA) levels. Thus, the results indicate a low subchronic toxicity of the tested materials in mice and a possible alteration in the oxidative metabolism. However, further tests are required to better elucidate the effects of these compounds in the antioxidant system.  相似文献   

5.
Sipjeondaebo-tang (SDT, Juzen-taiho-to in Japanese), a traditional Korean herbal medicine, is used as a supplemental treatment for the adverse effects of chemotherapy, radiation therapy, and surgical treatment. However, limited information is available about the long-term safety of SDT. Therefore, we evaluated the potential adverse effects of SDT in Sprague-Dawley rats over a period of 13-weeks. The SDT was administered once daily by gavage to male and female rats at dose levels of 0, 250, 500, 1000 and 2000 mg/kg/day for 13 weeks. The SDT treatment did not result in any toxicologically significant changes in mortality, clinical signs, body weights, food and water consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights, histopathology, estrus cycle, serum testosterone levels and sperm analysis. We concluded that the 13-week repeated oral administration of SDT did not cause any adverse effects in rats at dose levels of ≤ 2000 mg/kg/day. Under these experimental conditions, the no-observed-adverse-effect level (NOAEL) was more than 2000 mg/kg/day for both genders. Here, we demonstrated the safety of a 13-week repeated oral dose and considered that it is a safe herbal medicine for human consumption.  相似文献   

6.
Azinphos-methyl was evaluated for its subchronic inhalation toxicity. The exposure of rats to concentrations of 0.195, 1.24, and 4.72 mg/m3, respectively, for 12 weeks, 6 hrs daily, 5 times weekly, resulted in effects only in those animals which inhaled aerosols of the highest concentration. This group showed a significant depression of the cholinesterase activity in plasma and erythrocytes. The males of this group had a lower body weight gain. The results are in agreement with the established maximum allowable concentration of 0.2 mg/m3.  相似文献   

7.
The biocide diiodomethyl-p-tolylsulfone (DIMPTS) caused dystocia, decreased neonatal survival and hypothyroidism in rat reproduction studies resembling the effects caused by iodine. One molecule of DIMPTS contains two iodine moieties that are hydrolyzed upon ingestion and systemically absorbed, suggesting iodine toxicity as a probable mode of action for the effects observed in rats. This study compared the effects induced by DIMPTS and an equimolar concentration of its de-iodinated analogue, methyl-p-tolylsulfone (MPTS). Groups of 20 female Sprague Dawley rats were fed diets supplying 80 mg DIMPTS/kg/day, 32 mg MPTS/kg/day or control feed from prior to breeding through lactation and gonadal function, mating performance, conception, gestation, parturition, lactation, survival, growth and development of pups evaluated through postnatal day 7. Serum thyroid hormones and iodine levels in milk and sera were also determined. Females given DIMPTS had increased incidence of vulvar discharge and dystocia, decreased litter size, decreased body weights and feed consumption, increased thyroid weights, thyroid follicular cell hypertrophy with decreased colloid, decreased triidothyronine, and increased thyroid stimulating hormone levels. DIMPTS pups had decreased neonatal survival and body weights. These effects were associated with elevated levels of iodine in milk and sera. In contrast, MPTS did not produce similar effects in adult females or their offspring. These data support the hypothesis that the dystocia, altered neonatal survival and hypothyroidism following repeated dietary administration of DIMPTS were due to excessive iodine released from DIMPTS during absorption and metabolism.  相似文献   

8.
Tertiary-butyl acetate (TBAC) was tested for subchronic toxicity in rats and mice and reproductive toxicity in rats at inhalation concentrations of 0, 100, 400 or 1600 ppm. An oral maternal toxicity study was conducted in rats at dose levels of 0, 400, 800, 1000 and 1600 mg kg−1 d−1. In the inhalation studies, hematology, clinical chemistry, urinalysis, gross pathology and the majority of body weight and feed consumption values were unaffected. Exposure to TBAC at concentrations of 400 ppm and higher caused transient hyperactivity in mice and some evidence of increased motor activity counts in male rats at the 1600 ppm exposure level. TBAC caused α2u-globulin accumulation in male rat kidneys from all exposure groups and increased liver weights in 1600 ppm rats and mice. Levels of thyroxin were decreased in male mice exposed to 1600 ppm TBAC for 4 weeks but otherwise thyroid endpoints were unaffected in rats and mice at either the 4 or 13 weeks time points. There was no evidence or immunotoxicity or reproductive toxicity in rats. Pregnant rats receiving 1000 mg kg−1 d−1 TBAC exhibited severe signs of acute neurotoxicity and decreased feed consumption and body weight gain. Fetal viability and growth were unaffected.  相似文献   

9.
Conjugated linoleic acid (CLA) is the term given to a group of positional and geometric isomers of the essential fatty acid linoleic acid. CLA is found naturally in foods such as dairy and meat products. CLA is reported to have a number of beneficial effects including anticarcinogenic activity. However, safety data are limited. Clarinol™ G80 is a commercial preparation containing equal amounts of the 9cis,11trans and 10trans,12cis CLA isomers in the form of glycerides. In order to support the safety-in-use of Clarinol™ G80 as an ingredient in food, the preparation was tested in two in vitro mutagenicity assays, an Ames test and an in vitro cytogenetics assay, and a 90-day repeat-dose oral toxicity rat study. Clarinol™ G80 was non-mutagenic in both in vitro assays. In the 90-day study, Clarinol™ G80 produced hepatocellular hypertrophy in female rats at the highest dose level (15% w/w). This effect was an adaptive effect in response to feeding high levels of Clarinol™ G80 in the diet and was reversible upon withdrawal of test material. An increase in plasma insulin levels was also observed female rats fed 15% w/w Clarinol™ G80 but there was no effect on plasma glucose levels. A No Observed Adverse Effect Level of 2433 mg/kg bw/day for male and 2728 mg/kg bw/day female rats was identified in the study.  相似文献   

10.
Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days.  相似文献   

11.
Agaricus blazei Murrill, an edible mushroom, is used as a functional food due to medicinal effects of (1→6)-β-D-glucan protein complex which has been shown to have anti tumour activity in mice. A 13 week oral subchronic study in rats performed at 500, 1000 or 2000 mg/kg/day caused, at the highest dose, reduced erythrocyte numbers and high mean cell volume in males, high creatinine and urea concentrations in both sexes and low spleen weights in females, but no histopathological change. The findings suggested low level chronic toxicity at 2000 mg/kg/day and a no observed adverse effect level (NOAEL) of 1000 mg/kg/day. Genotoxicity tests on the aqueous extract were negative in the bacterial reverse mutation test, either with or without S9 mix, up to 5000 μg/plate and in a rat bone marrow micronucleus test up to 2 g/kg bodyweight. The extract was positive at acceptable levels of toxicity in an L5178Y mouse lymphoma assay following 24 h exposure in the absence of S9 and this was associated with an increase in the number of small colonies, suggesting possible clastogenic activity or aneuploidy, rather than point mutation. The aqueous extract of A. blazei is therefore of low subchronic toxicity and did not cause any direct effect upon the DNA molecule and the weak positive in the L5178 mouse lymphoma test was likely due to large deletions or the loss of the whole chromosomes rather than to direct damage to the DNA.  相似文献   

12.
研究黄蜀葵花提取物金丝桃苷的急性毒性和遗传毒性,对其安全性进行评价。急性毒性试验中,选用健康BALB/c小鼠40只,雌雄各半,灌胃给药(5000mg/kg),连续观察14天,记录中毒和死亡情况,测定小鼠的半数致死量(LD50)。用目前新药遗传毒性评价中推荐使用的3种试验方法,营养缺陷型鼠伤寒沙门氏菌回复突变试验(Ames试验),中国仓鼠肺成纤维细胞(CHL)染色体畸变试验和小鼠骨髓微核试验研究金丝桃苷的遗传毒性。在急性毒性试验中,所有实验动物都存活,且行为活泼,未见明显异常。Ames试验中,金丝桃苷在加或不加肝微粒体酶(S9)时均未见引起TA97、TA98、TAl00和TAl02试验菌株基因突变(P>0.05)。体外CHL细胞染色体畸变试验中,金丝桃苷在加或不加S9时均未引起CHL细胞的染色体畸变(P>0.05)。小鼠微核试验中,金丝桃苷各剂量组小鼠骨髓多染红细胞微核率与阴性对照组相比,差异无统计学意义(P>0.05)。在本实验条件下,金丝桃苷对于BALB/c小鼠的LD50大于5000mg/kg,金丝桃苷没有遗传毒性。  相似文献   

13.
The subchronic oral toxicity of microcystin in common carp (Cyprinus carpio L.) was investigated in this study. The fish (mean body weight of 322±36 g, n=10) were orally exposed to Microcystis by feeding with bloom scum at a dose of 50 μg microcystins/kg body weight under laboratory conditions for 28 days. Growth assay results showed that microcystin could completely inhibit the growth of carp, but failed to change the fish hepatosomatic index. Ultrastructural examination by electron microscope revealed severe damage in hepatocytes derived from the treated fish. Serum biochemical assays with commercial kits indicated that alanine aminotransferase and aspartate aminotransferase activities were significantly increased as compared to control levels, but γ-glutamyl transferase, alkaline phosphatase and lactate dehydrogenase activities remained unchanged. Protein phosphatase inhibition assay revealed that the microcystin concentrations were 261.0±108.3 ng microcystin-LR equivalent/g fresh weight in hepatopancreas and 38.3±12.3 ng microcystin-LR equivalent/g fresh weight in muscle. The latter is above the limit recommended by the World Health Organization for human consumption. Therefore, we recommend that a warning system be instituted for announcing the occurrence of microcystin-producing water bloom and the possible risk of human intoxication.  相似文献   

14.
The subchronic toxicity and toxicokinetics of Bencycloquidium bromide (BCQB) were evaluated after 91-day intranasal administration in dogs at daily dose levels of 2.5, 5.0, and 10.0 mg/kg. Following repeated exposure to medium- or high-dose of BCQB, apparent changes were observed in the levels of blood glucose, creatinine or blood urea nitrogen in both male and female dogs. The no-observed-adverse-effect level (NOAEL) of BCQB was considered to be 2.5 mg/kg/day under the present study conditions. There were no significant gender differences in most indexes of subchronic toxicity throughout the experimental period with the exception of food consumption and body weight, or in the parameters of plasma toxicokinetics after either single-dose or repeated administrations of BCQB at each dosage. In dog, BCQB did not accumulate in blood plasma, while much higher concentrations of BCQB residues were found in most tissues examined (especially the kidney) following 91-day repeated exposure relative to a single dose. In all tissues except the reproductive organs, BCQB concentrations reverted to low levels by 2 weeks post-dosing. The results indicate that blood glucose levels and renal function should be closely monitored when BCQB is used in long-term therapy.  相似文献   

15.
This study examined in rats the subchronic toxicity and anti- HSV-1activity after oral administration of dolabelladienetriol (D1), a diterpene isolated from the seaweed Dictyota pfaffii. In subchronic toxicity (SCT) tests, female rats received D1 by gavage 15 mg/kg/day (n = 5) for 50 days, and general behavior, death, hematological, biochemical and histological changes in the liver, kidney, stomach, and duodenum were determined. For the anti-HSV-1 activity, female mice were infected and treated orally with a dose of 20 mg/kg (n = 5) twice a day with D1 and any lesions in the skin were then recorded for 18 days. Dolabelladienetriol in SCT did not significantly change behavior, body weight, hematological or biochemical profiles. The liver and kidneys, however, showed some alterations in rats treated with D1, similar to those in rats treated with ACV, while the other tissues had no significant changes. The anti-HSV-1 activity of D1 had a similar efficacy to the ACV drug control in mice. Our results showed that D1 has potential commercial development as a new HSV-1drug.  相似文献   

16.
含氟吸入麻醉剂的生殖毒性研究进展   总被引:1,自引:0,他引:1  
含氟吸入麻醉剂的毒性研究主要集中在肝脏损害、肾脏损害和心血管抑制方面,其在生殖毒性方面的研究相对较少.近几年的研究表明,含氟吸入麻醉剂不但在细胞水平上能够影响细胞的分化,还能在分子水平上破坏染色体DNA的结构,但其具体作用机制现在还不十分清楚,本文就吸入麻醉剂的生殖毒性研究进展作一综述.  相似文献   

17.
Concerns regarding the adverse effects of long-term exposure to low levels of rare earth elements (REEs) from foods on human health have arisen in recent years. Nevertheless, no official acceptable daily intake (ADI) has yet been proposed for either total REEs or individual REE. In accordance with the Organization for Economic Co-operation and Development (OECD) testing guideline, the present study was undertaken to evaluate the subchronic toxicity of yttrium, a representative heavy REE with higher contaminated level in foods in China, to achieve a no observed adverse effect level (NOAEL) which is a critical basis for the establishment of an ADI. Yttrium nitrate was orally administered to rats at doses of 0, 10, 30 and 90 mg/kg/day for 90 days followed by a recovery period of 4 weeks. The following toxicity indices were measured: mortality, clinical signs, daily food consumption and weekly body weight; urinalysis, hematology, blood coagulation, clinical biochemistry and histopathology at the end of administration and recovery periods. No toxicologically significant changes were found in any yttrium-treated group as compared to the concurrent control group. Under the present experimental condition, the NOAEL in rats was thus set at 90 mg/kg for yttrium nitrate, i.e. 29.1 mg/kg for yttrium.  相似文献   

18.
In this study, Beagle dogs were administered xylooligosaccharide (XOS, CAS # 87099-0) at doses of 0, 1250, 2500, and 5000 mg/kg/day by oral gavage for 26 weeks. A 4-week recovery period was added to observe delayed or reversible toxicity. Measurements included body weight, food consumption, clinical observations, temperature, electrocardiogram (ECG), urinalysis, blood chemistry, hematology, organ weight, gross necropsy, and histopathological examination. Except for transient diarrhea or vomiting, no treatment-related adverse effects were noted. In the mid-dose groups, transitional diarrhea was observed in the initial 1–2 weeks. In the high-dose groups, diarrhea and/or vomiting were observed episodically over the duration of treatment. However, they disappeared after XOS was withdrawn in the recovery period. Although there was a tendency toward less weight gain in the high-dose group animal group, this is typical in animals and humans fed non-digestible carbohydrates. This chronic toxicity study demonstrated that the no observed adverse effect level (NOAEL) of XOS is 2500 mg/kg body weight (BW)/day. Based on body surface area (conversion factor of 0.54 for dogs to human), this corresponds to daily doses of 1350 mg/kg BW or 81–108 g XOS in human adults weighing 60–80 kg.  相似文献   

19.
The safety of an açai (Euterpe oleracea Mart.) pulp enriched fruit and berry juice, MonaVie Active®, fortified with the functional ingredient, glucosamine, was studied. The beverage was found not to be mutagenic, clastogenic, cytotoxic, or genotoxic, as determined by the bacterial reverse mutation assay, chromosomal aberration assay, mouse micronucleus assay, and mammalian cell gene mutation (L5178Y) assay. The single dose LD50 based on a 14-day acute oral toxicity study is greater than 20,000 mg/kg bw, the highest dose tested. In a repeat dose 90-day oral subchronic toxicity study by gavage, 220 animals were randomly assigned to a control group, an untreated group, or one of three experimental groups (10, 20 and 40 g/kg bw). No treatment-related significant changes in body weight, food and water consumption, ophthalmology, organ weights, urinanalysis, hematological and clinical chemistry, or gross pathology, were observed in surviving animals compared to the control groups. Three animals died midway through the observation period (male, 20 g/kg bw/day; male 40 g/kg bw/day; and, female, 10 g/kg bw/day). These animals died without preceding clinical symptoms, histopathological lesions, or evidence of injury to tissue or organs except for signs of suffocation/aspiration congestion, which was concluded to be due to problems with the gavage administration of the fluid test article, and not due to the test article itself. The NOEAL was determined to be 40 g/kg bw/day for male and female rats, which was the highest dose tested. Phylloquinone (vitamin K1) content averaged 21.7 μg/100 g, comparable to amounts found in iceberg lettuce. In conclusion, the results provide additional experimental evidence that MonaVie Active® juice is non-toxic.  相似文献   

20.
A new trend has been developed using vanadium and organic ligands to form novel compounds in order to improve the beneficial actions and reduce the toxicity of vanadium compounds. In present study, vanadyl trehalose was explored the oral acute toxicity, 28 days repeated dose toxicity and genotoxicity in Kunming mice. The Median Lethal Dose (LD50) of vanadyl trehalose was revealed to be 1000 mg/kg body weight in fasted Kunming mice. Stomach and intestine were demonstrated to be the main target organs of vanadyl trehalose through 28 days repeated dose toxicity study. And vanadyl trehalose also showed particular genotoxicity through mouse bone marrow micronucleus and mouse sperm malformation assay. In brief, vanadyl trehalose presented certain, but finite toxicity, which may provide experimental basis for the clinical application.  相似文献   

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