Objective To investigate the subchronic oral toxicity of silica nanoparticles（NPs） and silica microparticles（MPs） in rats and to compare the difference in toxicity between two particle sizes.Methods Sprague-Dawley...Objective To investigate the subchronic oral toxicity of silica nanoparticles（NPs） and silica microparticles（MPs） in rats and to compare the difference in toxicity between two particle sizes.Methods Sprague-Dawley rats were randomly divided into seven groups： the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups [166.7,500, and 1,500 mg/（kg·bw·day）]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver,kidneys, and testis were determined.Results There were no toxicologically significant changes in mortality, clinical signs, body weight,food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups.Conclusion Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats.展开更多
This study was conducted to assess the effects of caffeine on the dam and the physical development of rat offspring.Pregnant Sprague-Dawley rats(20 per dose group)were administered caffeine by gavage at 0(control),5,2...This study was conducted to assess the effects of caffeine on the dam and the physical development of rat offspring.Pregnant Sprague-Dawley rats(20 per dose group)were administered caffeine by gavage at 0(control),5,20,and 80 mg/kg body weight(bw)daily from gestational day 6 through lactation using caffeine dissolved in water.The developmental toxicity of caffeine was evaluated.Dams in the 80 mg/kg bw group exhibited splenic atrophy.The litter weights were significantly lower in the 20 and 80 mg/kg bw groups than the untreated control(P<0.05),with a greater reduction in the higher dose group.The number of female offspring was reduced in the 20 and 80 mg/kg bw groups(P<0.05).Some of the offspring were eaten by the dam following birth,which accounted for half of the litters in the 80 mg/kg bw group(P<0.05).Offspring body weight in the 80 mg/kg bw group was lower than that in the control during the lactation period(P<0.05).Exposure to caffeine during pregnancy can cause maternal immune dysfunction and intrauterine growth restriction retardation(IUGR);the developmental toxicity of caffeine varied with gender,as females were more sensitive than males.The no observed adverse effect level was 5 mg/kg bw based on the IUGR.展开更多
To evaluate hormesis induced by Yttrium（Y） nitrate in male rats, Y was offered to F0 mother rats and F1 offspring at concentrations of 0, 20, 80, and320 ppm daily from gestational day （GD） 0 through postnatal day...To evaluate hormesis induced by Yttrium（Y） nitrate in male rats, Y was offered to F0 mother rats and F1 offspring at concentrations of 0, 20, 80, and320 ppm daily from gestational day （GD） 0 through postnatal day 70（PND70）.The F1 offspring were evaluated with respect to motor function,learning and memory, and histopathology.展开更多
基金supported by China Food Safety Talent Competency Development Initiative:CFSA 523 Program
文摘Objective To investigate the subchronic oral toxicity of silica nanoparticles（NPs） and silica microparticles（MPs） in rats and to compare the difference in toxicity between two particle sizes.Methods Sprague-Dawley rats were randomly divided into seven groups： the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups [166.7,500, and 1,500 mg/（kg·bw·day）]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver,kidneys, and testis were determined.Results There were no toxicologically significant changes in mortality, clinical signs, body weight,food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups.Conclusion Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats.
基金supported by the National Key Research and Development Program of China[2017YFC1601702]Funding for Basic Scientific Research Operation of Central Universities[3142019002].
文摘This study was conducted to assess the effects of caffeine on the dam and the physical development of rat offspring.Pregnant Sprague-Dawley rats(20 per dose group)were administered caffeine by gavage at 0(control),5,20,and 80 mg/kg body weight(bw)daily from gestational day 6 through lactation using caffeine dissolved in water.The developmental toxicity of caffeine was evaluated.Dams in the 80 mg/kg bw group exhibited splenic atrophy.The litter weights were significantly lower in the 20 and 80 mg/kg bw groups than the untreated control(P<0.05),with a greater reduction in the higher dose group.The number of female offspring was reduced in the 20 and 80 mg/kg bw groups(P<0.05).Some of the offspring were eaten by the dam following birth,which accounted for half of the litters in the 80 mg/kg bw group(P<0.05).Offspring body weight in the 80 mg/kg bw group was lower than that in the control during the lactation period(P<0.05).Exposure to caffeine during pregnancy can cause maternal immune dysfunction and intrauterine growth restriction retardation(IUGR);the developmental toxicity of caffeine varied with gender,as females were more sensitive than males.The no observed adverse effect level was 5 mg/kg bw based on the IUGR.
基金supported by the National Key Research and Development Program of China [2017YFC1601701]Fundamental Research Funds for the Central Universities [3142018038]
文摘To evaluate hormesis induced by Yttrium（Y） nitrate in male rats, Y was offered to F0 mother rats and F1 offspring at concentrations of 0, 20, 80, and320 ppm daily from gestational day （GD） 0 through postnatal day 70（PND70）.The F1 offspring were evaluated with respect to motor function,learning and memory, and histopathology.
