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1.
The toxicity profile of the aqueous methanolic extract of Berlina grandiflora (BG) stem bark was studied in rats. The rats were administered graded doses (125-500 mg/kg p.o) of the extract daily for 21 days and the effects on body weight, organ weight, clinical signs, gross pathology, hematology, histology and serum biochemical parameters were measured. The relative weights of the heart, liver, kidneys and lungs of treated rats were unaffected but there were significant changes in the relative weights of the spleen and testes. The packed cell volume and hemoglobin concentrations were slightly reduced whereas total leucocytes counts were increased remarkably. Alkaline phosphatase and Creatine Kinase levels were reduced in all the groups but Glutamate oxaloacetate was significantly elevated. Total proteins and albumin levels remained normal. BG elicited a significant increase in gamma glutamyl transferase concentrations at 250 mg/kg. No significant changes occurred in urea, uric acid and BUN concentrations but calcium levels shot up remarkably. Histological findings did not reveal any treatment-related effects. The acute toxicity LD50 was estimated to be >2000 mg/kg but dose-related mortality rates of 16.7, 33.4 and 50% were observed during the sub-acute toxicity studies. These findings have once more highlighted the limitations of acute toxicity LD50 testing and suggest that BG may exert varied toxicological effects when administered orally in rats.  相似文献   

2.
Oral and intra-peritoneal acute toxicity and the sub-chronic intra-peritoneal toxicity of the essential oil of Ocimum gratissimum Linn, Lamiaceae (Ocimum oil), was investigated. The acute toxicity test involved the oral and intra-peritoneal administration of graded doses of Ocimum oil prepared as a 4% v/v emulsion to 2 groups each of 30 rats and mice. LD50 and LD100 were determined for both routes and species. In the sub-chronic toxicity study, 25 male Sprague-Dawley rats were randomized into 4 test groups (treated with three graded sub-lethal doses of Ocimum oil prepared as a 4% v/v emulsion) and a control. Organs and blood samples were taken for analyses after a 30 day treatment period. A dose-dependent sedative effect of Ocimum oil was observed during the acute toxicity study in mice and rats and in the sub-chronic test in rats. Evidence of treatment, route, and dose-dependent toxicity were detected in both studies. Changes in weight of the testes, hearts, kidneys, intestines and lungs of the rats were statistically insignificant (ANOVA P < 0.05). Data analyses of blood biochemical, haematological and histopathological findings showed significant differences between control and treated groups and revealed that Ocimum oil is capable of invoking an inflammatory response that transits from acute to chronic on persistent administration. While the study revealed that Ocimum oil might be better tolerated when administered orally for systemic delivery, the oil has toxic potentialities that should not be overlooked.  相似文献   

3.
Citrullus lanatus (Cucurbitaceae) is conventionally used for the treatment of urinary tract infection, renal stones, hypertension, diabetes and diarrhoea. Current study evaluates acute and 28 days repeated toxicity ethanolic extract of C. lanatus seed (EECLS) in Wistar rats to measure its safety profile. The single dose (2000 mg/kg BW) of EECLS was administered while in 28 days repeated study 250, 500 and 1000 mg/kg BW were administered orally in rats. Parameters such as biochemical, haematological and histopathological were analysed in subacute toxicity study. During study, no apparent sign of toxicity, behavioural changes and mortality were detected in acutely exposed animals. In 28 days repeated toxicity study, rats did not show significant changes in behaviour, gross pathology, body weight, biochemical and haematological parameters. Abridged serum glucose and cholesterol levels during the study designate their roles in treatment of hyperglycaemic and hyperlipidaemic conditions. No significant difference was observed in histopathology of liver and kidneys of treated rats. The current investigation demonstrated that EECLS is non-toxic below 1000 mg/kg BW and provides protection to some body organs. The data propose that LD50 of EECLS was greater than 2000 mg/kg BW and the no observed adverse effect level (NOAEL) of EECLS was at the dose of 1000 mg/kg in rats. Taken together, our finding suggests that, EECLS is safe and provides some protection to body organs; also, its extract can be used for further preclinical and clinical evaluation for its therapeutic activity.  相似文献   

4.
The acute toxicity of standardized extract of Orthosiphon stamineus was studied in Sprague Dawley rats. The rats were administered a single dose of 5000 mg/kg body weight (BW) orally on Day 0 and observed for 14 days. There were no deaths recorded and the animals did not show signs of toxicity during the experimental period. The effect of the extract on general behavior, BW, food and water intake, relative organ weight per 100 g BW, hematology and clinical biochemistry were measured. All the parameters measured were unaffected as compared to the control. The acute toxicity LD50 was estimated to be >5000 mg/kg BW.  相似文献   

5.
The pesticide malathion (MT), an organophosphate, is highly neurotoxic and causes cholinergic disorders as well as cytotoxicity, genotoxicity, mutagenicity, carcinogenicity and reproductive toxicity. Our purpose was to study the effect of ellagic acid (EA) and Vitamin C on the testis against MT-induced toxicity in the rats. Thirty-six adult Wistar rats were employed, separated into six groups and were given treatment for 14 days. The toxicity of MT on the testis was evaluated using a variety of physical parameters, such as mortality rate and body weight, as well as biochemical parameters, such as total protein, total cholesterol, serum glutamic-oxaloacetic transaminase and serum glutamic-pyruvic transaminase, and haematological parameters, such as counts of red blood cells, haemoglobin (Hb) and white blood cells, as well as mean corpuscular volume, mean corpuscular Hb, and mean corpuscular Hb concentration. At the end of the experiment, rats were killed and a histological examination of the testis was performed. A sperm count technique and an analysis of sperm motility were used to determine the sperm quality. Biochemical indicators, sperm count, motility, viability and morphology were significantly decreased with MT. When compared with MT and the control group, EA and Vitamin C administration significantly increased sperm motility and count (p < 0.05). After receiving EA and Vitamin C, biochemical indicators and histological characteristics are also intensified. The results of the current investigation show that EA and Vitamin C can both reduce increased levels of biochemical markers and improve pathological alterations in the testis brought on by MT treatment.  相似文献   

6.
ObjectiveTo evaluate the effects of yttrium nitrate on the development of the parent, offspring and third generation of Sprague-Dawley (SD) rats by using a two-generation reproductive toxicity test.MethodsThe SD rats were randomly divided into 0 mg/kg group, 10.0 mg/kg group, 30.0 mg/kg group and 90.0 mg/kg group according to the different doses of yttrium nitrate administration. The reproductive toxicity of parent, offspring and third generation SD rats were compared.ResultsThe weight gains of F1a female rats and F2a female rats in the low-dose groups were significantly lower than those of the control groups (p < 0.05), the weight gains of F1a male rats in the medium-dose and high-dose groups were significantly lower than those of the control groups (p < 0.05), and the weight gains of F2a male rats in the low-dose, medium-dose and high-dose groups were significantly lower than those of the control groups (p < 0.05). In F0 male rats, the absolute weight and relative weight of the liver in the low-dose, middle-dose, and high-dose groups were significantly lower than those of the control group (p < 0.05). In F1b male rats, the absolute and relative weights of the liver in the medium-dose and high-dose groups were significantly lower than those of the control group (p < 0.05). In F2b male rats, the absolute and relative weights of the liver and spleen of the medium-dose and high-dose groups were significantly lower than those of the control group (p < 0.05). In F2a female rats, the absolute weight and relative weight of oviduct in the high-dose group were significantly lower than those in the control group (p < 0.05). The absolute and relative weights of lung, spleen, brain and uterus of F2b female rats in the high-dose group were higher than those of the control group (p < 0.05). But the pathological test results showed no hepatotoxicity. There was no statistically significant difference in sperm count and sperm motility between male rats in the yttrium nitrate administration groups and the control group (p > 0.05). There was no significant correlation between F0, F1a, F1b, F2a, F2b SD rats' reproductive organ lesions and the dose of yttrium nitrate.ConclusionYttrium nitrate at a dose of 90 mg/kg has no reproductive toxicity to two generations of SD rats, but 30.0 mg/kg dose of yttrium nitrate is toxic to the liver weight of male two generations of SD rats, but no hepatotoxicity.  相似文献   

7.
Acute and 90‐day subchronic oral toxicity studies were conducted to establish the safety evaluation of xylanases preparations. A potential oxidative stress evaluation was also performed through testing the generation of oxidative radicals, depletion of antioxidants via oxidative modification of lipids, proteins and DNA of organ cells. During the subchronic oral toxicity study, no mortality was observed, obvious treatment‐related clinical signs and urinalysis parameters were in normal range. Differences in some hematological parameters, biochemistry, relative organ weight, and histopathology examinations between the treated group and the control group were not judged to be adverse. Our results indicated that the no‐observed‐adverse‐effect level for xylanases was 1,500 TXU/kg/day and the plasma antioxidant assays showed that these xylanases did not produce free‐radicals nor oxidative injuries. On the basis of the bacterial reverse mutation assay data, it is concluded that the expressed xylanase in Pichia pastoris do not present any mutagenic potential when tested in relevant genotoxicological assays.  相似文献   

8.
Cadmium (Cd) is a toxic environmental and occupational pollutant with reported toxic effects on the kidneys, liver, lungs, bones, and the immunity system. Based on its physicochemical similarity to cadmium, zinc (Zn) shows protective effects against cadmium toxicity and cadmium accumulation in the body. Nano-zinc and nano-zinc oxide (ZnO), recently used in foods and pharmaceutical products, can release a great amount of Zn2+ in their environment. This research was carried out to investigate the more potent properties of the metal zinc among sub-acute cadmium intoxicated rats. Seventy-five male Wistar rats were caged in 15 groups. Cadmium chloride (CdCl2) was used in drinking water to induce cadmium toxicity. Different sizes (15, 20, and 30 nm) and doses of nano-zinc particles (3, 10, 100 mg/kg body weight [bw]) were administered solely and simultaneously with CdCl2 (2–5 mg/kg bw) for 28 days. The experimental animals were decapitated, and the biochemical biomarkers (enzymatic and non-enzymatic) were determined in their serum after oral exposure to nano-zinc and cadmium. Statistical analysis was carried out with a one-way ANOVA and t test. P < 0.05 was considered as statistically significant. The haematocrit (HCT) significantly increased and blood coagulation time significantly reduced in the nano-zinc-treated rats. AST, ALT, triglyceride, total cholesterol, LDL, and free fatty acids increased significantly in the cadmium- and nano-zinc-treated rats compared with the controls. However, albumin, total protein, and HDLc significantly decreased in the cadmium- and nano-zinc-treated rats compared with the controls (P < 0.05). It seems that in the oral administration of nano-zinc, the smaller sizes with low doses and the larger sizes with high doses are more toxic than metallic zinc. In a few cases, an inverse dose-dependent relationship was seen as well. This research showed that in spite of larger sizes of zinc, smaller sizes of nano-zinc particles are not suitable for protection against cadmium intoxication.  相似文献   

9.
精制木醋液的安全性评价   总被引:4,自引:0,他引:4  
目的:通过观察实验动物使用木醋液后的急、慢性毒性反应,评估精制木醋液的安全性.方法:①昆明种小鼠,雌雄各10只,木醋液经口灌胃1次,观察1周,并记录动物急性中毒症状及死亡情况.②Wistar大鼠80只,分为受试物高、中、低剂量组和空白对照组,经口灌胃30 d后,观察大鼠血液学、血液生化学及心、肝、脾、肺、肾、胃等主要脏器病理变化.结果:①1周内小鼠未见明显中毒症状及死亡发生,最大耐受剂量为20 g/kg.②30 d后大剂量组血清ALT明显升高,包括对照组偶见肝细胞脂肪变性或糖源变性,但各组间没有显著性差异,其他血液学、生化学、脏器重量和病理检查等无明显变化.结论:本品除了大剂量组出现轻微的生化毒性外,没有发现与受试物有关的其他毒性变化.  相似文献   

10.
The mycotoxin cyclopiazonic acid (CPA) is a potential contaminant of processed foods, grain and poultry. Twelve male Sprague-Dawley rats were given oral doses of 0, 0.2, 0.6, 2.0 or 4.0 mg CPA/kg body weight/day for 13 consecutive weeks to study its potential subchronic toxicity. No dose-related mortality or morbidity occurred. General appearance, behavior, body weight gain and food consumption of all groups were similar. CPA had no definite adverse hematologic or serum chemistry effects, although serum creatinine concentrations of rats given 2.0 and 4.0 mg CPA/kg BW were increased after seven and 13 weeks. Mild to focally moderate acute inflammation of the lamina propria and submucosa of the gastric epithelium was found in animals given 0.6 mg CPA/kg BW. No other dose-related microscopic lesions were found. Ultrastructural examination of the livers revealed subtle disruption of the cisternal pattern of the endoplasmic reticulum with ribosomal detachment in animals receiving 4.0, but not 2.0, mg CPA/kg BW. These data suggest that the toxic effects in rats of repeated, daily oral exposure to CPA may be less than previously reported. The possible relationship between toxicity and CPA epimerization is considered.  相似文献   

11.
Nanometer zinc oxide (nano-ZnO) is widely used in diverse industrial and agricultural fields. Due to the extensive contact humans have with these particles, it is crucial to understand the potential effects that nano-ZnO have on human health. Currently, information related to the toxicity and mechanisms of nano-ZnO is limited. The aim of the present study was to investigate acute and cumulative toxic effects of 50-nm unmodified ZnO in mice. This investigation will seek to establish median lethal dose (LD50), a cumulative coefficient, and target organs. The acute and cumulative toxicity was investigated by Karber’s method and via a dose-increasing method, respectively. During the experiment, clinical signs, mortality, body weights, hematology, serum biochemistry, gross pathology, organ weight, and histopathology were examined. The LD50 was 5177-mg/kg·bw; the 95% confidence limits for the LD50 were 5116–5238-mg/kg·bw. It could be concluded that the liver, kidney, lung, and gastrointestinal tract were target organs for the 50-nm nano-ZnO acute oral treatment. The cumulative coefficient (K) was 1.9 which indicated that the cumulative toxicity was apparent. The results also indicated that the liver, kidney, lung, and pancrea were target organs for 50-nm nano-ZnO cumulative oral exposure and might be target organs for subchronic and chronic toxicity of oral administered 50-nm ZnO.  相似文献   

12.
BackgroundIn this study, chromium (III) complex was synthesized from genistein (GEN) which had good hypoglycemic activity and inorganic chromium (III) element, and its hypoglycemic activity and sub-acute toxicity were studied.MethodsThe genistein-chromium (III) complex was synthesized by chelating chromium with genistein in ethanol and its structure was determined by LC–MS, atomic absorption spectroscopy, UV–vis spectroscopy, infrared spectroscopy, elemental and thermodynamic analysis. The anti-diabetic activity of the complex was assessed in db/db mice and C57 mice by daily oral gavage for 4 weeks. The sub-acute toxicity test was carried out on KM mice with this complex.ResultsThe molecular structure of this complex was inferred as a complex [CrGEN3] formed by three ligands and one chromium element. The complex could significantly improve the body weight of db/db mice, fasting blood glucose, random blood glucose, organ index, glycogen levels and the performance of OGTT (Oral Glucose Tolerance Test) and ITT (Insulin Tolerance Test) in db/db mice (p < 0.05). The morphology of liver, kidney, pancreas and skeletal muscle also had obviously improvement and repairment. Effects on serum indices and antioxidant enzymes activities of db/db mice showed that the serum profiles and antioxidant ability of complex group had significant improvement compared with the diabetic control group (p < 0.05 or p < 0.01), and some indices even returned to normal levels. In addition, this complex did not produce any hazardous symptoms or deaths in sub-acute toxicity test. High dose of [CrGEN3] had no significant influence on serum indices and antioxidant capacity in normal mice, and the organ tissues maintained organized and integrity in the sub-acute toxicity study.ConclusionThe study of the genistein-chromium (III) complex showed that the complex had good hypoglycemic activity in vivo, and did not have the potential toxicity. These results would provide an important reference for the development of functional hypoglycemic foods or pharmaceuticals.  相似文献   

13.
为了探讨无瓣海桑的生物毒性作用,采用哺乳类动物大鼠,国际规定的标准毒性实验用鱼斑马鱼以及红树林内主要鱼种弹涂鱼为受体,进行了大鼠急性经口毒性固定剂量毒性反应观察,斑马鱼和弹涂鱼的改进寇氏法毒性实验以及半致死量浓度(LC50)和95%可信限计算,结果表明:在5000 mg/kg体重下,无瓣海桑的果实和叶子浸提液都未对大鼠产生任何毒性表现,14 d的死亡率为0,半致死量(LD50)大于5000 mg/kg体重,属于无毒物质;对鱼类毒性,相同鱼种下,果实水浸提液毒性强于叶子水浸提液,相同水浸提液下,弹涂鱼对毒性敏感度超过斑马鱼,半致死浓度24 hLC50>4 8 hLC50>72 hLC50>96 hLC50>1000 mg·L-1,属于低毒物质.根据以上初步得出无瓣海桑不会对周围生物造成毒性危害.  相似文献   

14.
Tungstate is an oxyanion that has biological similarities to vanadate. In recent years, a number of studies have shown the antidiabetic effects of oral tungstate in animal models of diabetes. However, because of the tissue accumulation and potential toxicity derived from chronic administration of vanadium and tungsten compounds, the pharmacological use of vanadate or tungstate in the treatment of diabetes is not necessarily exempt from concern. In the context of a potential use in the treatment of human diabetes mellitus, the most relevant toxic effects of vanadium derivatives are reviewed and compared with those reported for tungsten. Hematological and biochemical alterations, loss of body weight, nephrotoxicity, immunotoxicity, reproductive and developmental toxicity, and behavioral toxicity have been reported to occur following exposure to vanadium compounds. Moreover, vanadium also has a mitogenic activity affecting the distribution of chromosomes during mitosis and inducing aneuploidyrelated end points. In contrast to vanadate, studies about the toxic effects of tungstate are very scant. Early investigations in cats, rabbits, dogs, mice, and rats showed that tungstate was less toxic than vanadate when given intravenously. Although in vitro investigations showed a direct effect of tungstate on the embryo and fetus of mice at concentrations similar to those causing effects in vivo, information on the potential cellular toxicity of tungstate is particularly scarce. Taking into account the recent interest of tungstate as a new potential oral antidiabetic agent, an exhaustive evaluation of its toxicity in mammals is clearly necessary.  相似文献   

15.
Globally, human exposure to heavy metals has risen dramatically. Lead (Pb) is one of the most toxic heavy metals to human and other living organisms. Pb affects certain biochemical and physiological activities of the body. Many scientific investigations have documented the therapeutic and antioxidant properties of natural products which isolated from plant sources. The present study was therefore undertaken to evaluate the therapeutic influence of almond oil against Pb toxicity in male rats. The experimental rats were distributed into four groups. The first group was served as control. The second group was treated with 100 mg/kg body weight of Pb. The third group was subjected to almond oil (800 mg/kg body weight) and Pb. The fourth group was supplemented with almond oil. After six weeks, blood serum specimens were analyzed. In the second group, Pb produced a marked increase of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), total bilirubin, glucose, triglycerides, low density lipoprotein cholesterol (LDL-C), very low density lipoprotein cholesterol (VLDL-C), creatine kinase (CK), lactate dehydrogenase (LDH), creatinine, blood urea nitrogen (BUN), uric acid and malondialdehyde (MDA) levels, while the levels of total protein, albumin, high density lipoprotein cholesterol (HDL-C), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were significantly decreased. In contrast, the treatment with almond oil notably improved the biochemical changes and showed antioxidative effect. The present study disclosed the therapeutic influence of almond oil on the basis of its antioxidant effect against Pb toxicity. Moreover, these new findings indicated that the constituents of almond oil have a promising significant potential in biomedical and pharmacological studies.  相似文献   

16.
Dianex, a polyherbal formulation intended to use for diabetic patients, has been screened for toxic effects. For acute toxicity studies, Dianex was administered orally in graded doses of 0.75-10 g/kg to the mice. For subacute toxicity studies, different doses of Dianex (1.0, 1.5 and 2.5 g/kg) were administered orally to the rats once daily for 30 days. Animals were observed for physiological and behavioural responses, mortality, food and water intake and body weight changes. Hematological evaluation was performed weekly. All the animals were sacrificed on 31st day and changes in organ weights and histology were examined. Biochemical studies were done in liver and serum. No mortality was observed up to 10 g/kg of Dianex in acute toxicity study. Daily administration of as high as 2.5 g/kg dose of Dianex did not result in any mortality or changes in gross behaviour, body weight, weight and histology of different organs or serum and liver biochemistry. However, significant increase in RBC count and hemoglobin level was observed in the treated animals at all doses. Other peripheral blood constituents were in the normal range. The dose of Dianex to produce significant antidiabetic activity in mouse, 0.25-0.5 g/kg, is much lower than the doses used in the present study. Therefore such doses may be safe for daily administration without causing any serious side effects.  相似文献   

17.
A high oral concentration of 10g Al kg−1 dry weight promoted toxicant accumulation in the muscle, gill, liver, kidney and mucus of trout. One mortality occurred and only a small proportion of the exposure dose was retained by the fish. The limited acute oral toxicity of Al implies that contamination levels found in food species are unlikely to be acutely toxic to wild trout.  相似文献   

18.
The acute toxicity of potassium bromate (KBrO3) on rat small intestine was studied in this work. Animals were given a single oral dose of KBrO3 (100 mg/kg body weight) and sacrificed 12, 24, 48, 96 and 168 h after the treatment; control animals were not given KBrO3. The administration of KBrO3 resulted in a reversible decline in the specific activities of several BBM enzymes. Lipid peroxidation, protein oxidation and hydrogen peroxide levels increased while total sulfhydryl groups and reduced glutathione decreased in KBrO3-treated rats indicating induction of oxidative stress in the intestinal mucosa. The activities of anti-oxidant and carbohydrate metabolic enzymes were also altered upon KBrO3 treatment. The maximum changes in all the parameters were 48 h after administration of KBrO3 after which recovery took place, in many cases almost to control values after 168 h. Histopathological studies supported the biochemical findings showing extensive damage to the intestine at 48 h and recovery at 168 h. These results show that a single oral dose of KBrO3 causes reversible oxidative damage to the intestine.  相似文献   

19.
The safety of chemicals, drugs, novel foods and genetically modified crops is often tested using repeat-dose sub-acute toxicity tests in rats or mice. It is important to avoid misinterpretations of the results as these tests are used to help determine safe exposure levels in humans. Treated and control groups are compared for a range of haematological, biochemical and other biomarkers which may indicate tissue damage or other adverse effects. However, the statistical analysis and presentation of such data poses problems due to the large number of statistical tests which are involved. Often, it is not clear whether a “statistically significant” effect is real or a false positive (type I error) due to sampling variation. The author''s conclusions appear to be reached somewhat subjectively by the pattern of statistical significances, discounting those which they judge to be type I errors and ignoring any biomarker where the p-value is greater than p = 0.05. However, by using standardised effect sizes (SESs) a range of graphical methods and an over-all assessment of the mean absolute response can be made. The approach is an extension, not a replacement of existing methods. It is intended to assist toxicologists and regulators in the interpretation of the results. Here, the SES analysis has been applied to data from nine published sub-acute toxicity tests in order to compare the findings with those of the author''s. Line plots, box plots and bar plots show the pattern of response. Dose-response relationships are easily seen. A “bootstrap” test compares the mean absolute differences across dose groups. In four out of seven papers where the no observed adverse effect level (NOAEL) was estimated by the authors, it was set too high according to the bootstrap test, suggesting that possible toxicity is under-estimated.  相似文献   

20.
Multivitamin corn is a novel genetically engineered variety that simultaneously produces high levels of β‐carotene, ascorbate and folate, and therefore has the potential to address simultaneously multiple micronutrient deficiencies caused by the lack of vitamins A, B9 and C in developing country populations. As part of the development process for genetically engineered crops and following European Food Safety Authority (EFSA) recommendations, multivitamin corn must be tested in whole food/feed sub‐chronic animal feeding studies to ensure there are no adverse effects, and potential allergens must be identified. We carried out a 28‐day toxicity assessment in mice, which showed no short‐term sub‐acute evidence of diet‐related adverse health effects and no difference in clinical markers (food consumption, body weight, organ/tissue weight, haematological and biochemical blood parameters and histopathology) compared to mice fed on a control diet. A subsequent 90‐day sub‐chronic feeding study again showed no indications of toxicity compared to mice fed on control diets. Our data confirm that diets enriched with multivitamin corn have no adverse effects on mice, do not induce any clinical signs of toxicity and do not contain known allergens.  相似文献   

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