bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term carcinogenicity and toxicity study of zearalenone in the rat
Authors: Becci Peter J. , Voss Kenneth A. , Hess Frederick G. , Gallo Michael A. , Parent Richard A. , Stevens Kent R. , Taylor Jean M. 
Published: October 2006

AbstractThe effects of lifetime dietary administration of zearalenone, a fungal estrogen produced by Fusarium spp., were studied in FDRL Wistar rats. Animals were fed a control diet or a diet supplemented with zearalenone at levels of 0.1, 1.0 or 3.0 mg per kg body weight per day. The animals used were derived from F0 parents fed equivalent levels of zearalenone for 5 weeks before mating, and throughout mating and gestation, but not during lactation. Feeding of zearalenone at 1.0 and 3.0 mg kg−1 to male rats caused a significant decrease in body weight gain compared with controls. During the study, sporadic depressions in body weights occurred in females fed 1.0 and 3.0 mg per kg. However, no differences were noted at the end of the study. No significant differences among groups were found in the hematology, clinical chemistry or urine analysis data measured during or at the termination of the study. At the end of the study, significantly increased liver weights at the 3.0 mg kg−1 dose level and uterine weights at 1.0 and 3.0 mg kg−1 were noted in female rats. These weight differences did not correlate with any clinical or morphological finding. In rats receiving the high dose level of zearalenone, a greater incidence of increased medullary trabeculation of the femur was noted. The degree of medullary trabeculation was scored on a scale from 0 to 4; statistically significant increased scores were found in male and female rats at the high dose level compared to control rats. Other microscopic findings were unremarkable; no tumorigenic effect of zearalenone was noted.
Teratogenicity following inhalation exposure of rats to a high‐boiling coal liquid
Authors: Springer D. L. , Poston K. A. , Mahlum D. D. , Sikov M. R. 
Published: October 2006

AbstractOn days 12–16 of gestation pregnant rats were exposed to heavy distillate (HD), the highest‐boiling material derived from the solvent refined coal‐II (SRC‐II) process, and the litters were examined at day 21. Adverse biological effects were observed in the group of animals exposed to an aerosol concentration of 0.66 mg l−1 [1.8 μm, mass medium aerodynamic diameter (MMAD)]; groups of animals exposed to lower aerosol concentrations (0.084 and 0.017 mg l−1) were largely unaffected. Embryolethality during mid‐ and late gestation appeared attributable to the coal liquid exposure. Fetuses from pregnant rats in the high exposure group were smaller in weight and length than fetuses from control animals, and skeletal ossification was reduced. Increased incidences of small lungs and cleft palate were observed in fetuses from the high exposure group. Pregnant rats in the high‐exposure group gained less weight than controls during gestation; the reduced weight gain was accounted for by the reduced size of the fetuses and placentas. Even though maternal body weight (exclusive of the products of conception) was unaffected by the exposure, the weights of the maternal thymus, lung and spleen were altered in the high exposure group.
Short‐term toxicological studies with impromidine (SK&F 92676): A specific histamine H2‐receptor agonist
Authors: Leslie G. B. , Owen D. A. A. , Pollitt Frances D. , Sutton T. J. , Walker T. F. 
Published: October 2006

AbstractImpromidine is a specific, potent histamine H2‐receptor agonist. The present paper describes the results of acute and short‐term repeated‐dose toxicity studies with impromidine in rodents and dogs. The intravenous LD50 was 9.6 mg kg−1 in male mice, 12.7 mg kg−1 in female mice and 25.5 mg kg−1 in rats. The minimum lethal dose in dogs after 30 min intravenous infusion was 27.7 mg kg−1 during the infusion and 4 mg kg−1 within 14 days. In 12‐ or 14‐day tests in rats by the intravenous (maximum dose 3.24 mg per kg per day) and subcutaneous (maximum dose 20 mg per kg per day) routes, impromidine had no serious toxicological effects. In 12‐ or 14‐day studies in dogs by the i.v. (maximum dose 0.259 mg per kg per day) and intramuscular (maximum dose 0.5 mg per kg per day) routes, impromidine caused vasodilation, tachycardia and vomiting. In a few dogs, at the highest dose levels, there was erosion and irritation of the gastrointestinal tract and myocardial damage. Other minor pathological changes were seen in the liver, kidneys and pancreas. No changes were seen other than those to be expected from the pharmacological actions of impromidine as an H2‐receptor agonist. Studies in anaesthetized rats, either spontaneously respiring or sustained by artificial respiration, indicate that, at acute doses, impromidine causes death by respiratory failure.
Co‐enzyme effects of inorganic mercury in the liver of a freshwater fish Channa punctatus
Authors: Rana S. V. S. , Sharma Rekha 
Published: October 2006

AbstractMercury is known to modify enzyme activity through oxidation of thiol groups and respective reverse reactions in vitro and in vivo. However, variations in the activity of carbohydrases, and the significance of this variation after mercury poisoning in different species, has not been established. In the present report, the effects of inorganic mercury on selected hepatic enzymes was studied in the freshwater fish Channa punctatus. Quantitative data clearly showed a dose–response relationship between the amount of mercury retained in the liver and inhibition of enzymes (i.e. alkaline phosphatase, glucose‐6‐phosphatase, amylase, maltase, lactase, lipase and dehydrogenases). Mechanisms and significance of their modification have also been discussed.
Comparative effects of structurally related cyclodiene pesticides on ATPases
Authors: Mehrotra B. D. , Bansal S. K. , Desaiah D. 
Published: October 2006

AbstractComparative effects of aldrin, dieldrin, endrin, isodrin and telodrin, on different ATPase activities in beef heart mitochondrial and rat brain synaptosomal fractions were determined in vitro. Beef heart mitochondrial fractions were prepared by the conventional centrifugation method and the rat brain synaptosomes were prepared by Ficoll‐sucrose gradient centrifugation method. Na+–K+‐ATPase, oligomycin‐sensitive and ‐insensitive Mg2+‐ATPases, and K+‐paranitrophenylphosphatase were determined in rat brain synaptosomes. In beef heart mitochondria, only the Mg2+‐ATPase activities were determined. Concentration response curves were determined by assaying the enzyme activities in the absence and presence of 10–120 μM concentrations of each test chemical. Beef heart mitochondrial (oligomycin‐sensitive) Mg2+‐ATPase activity was inhibited by all five chemicals at all the concentrations tested. Aldrin and telodrin were the most potent inhibitors with an IC50 of 40 and 80 μM, respectively. About 30% was observed with dieldrin, endrin and isodrin, and the inhibition was not concentration‐dependent. Oligomycin‐insensitive Mg2+‐ATPase was not significantly inhibited by any chemical except aldrin. Rat brain synaptosomal ATPases were also sensitive to these compounds. Aldrin and telodrin were more effective than other compounds. A 50% inhibition of oligomycin‐sensitive Mg2+‐ATPase activity was obtained at 80 μM of aldrin and telodrin, Na+–K+‐ATPase and oligomycin‐insensitive Mg2+‐ATPase activities showed a maximum inhibition of 40% at the highest concentration tested for aldrin and telodrin. K+‐paranitrophenylphosphatase was not inhibited significantly by any compound tested. These results suggest that ATPase system in rat heart and CNS may be selectively inhibited by aldrin and telodrin, but not by their structural analogs.
Fluoride absorption through the hamster cheek pouch: A pH‐dependent event
Authors: Whitford G. M. , Callan R. S. , Wang H. S. 
Published: October 2006

AbstractThe fractional absorptions of fluoride, 3H2O, 125I and 14C‐DMO from the hamster cheek pouch were determined as functions of solution pH. When the pH was ≥5, fluoride absorption rate was inversely related to pH. The absorption rates of the other substances were not influenced by pH. The fractional absorptions of fluoride and 3H2O were independent of fluoride concentrations over the range 1–53 mM. The data indicate that the absorption of fluoride through this keratinized epithelium occurs mainly by the diffusion of non‐ionic HF.
Hydropic change in rat liver induced by hexachloro‐1 : 3–butadiene
Authors: Lock Edward A. , Ishmael John , Pratt Iona 
Published: October 2006

AbstractThe effect of a single i.p. dose of 200 or 300 mg kg−1 hexachloro‐1:3‐butadiene (HCBD) on liver morphology, water, sodium and potassium ion content, cation movement and non‐protein sulphydryl (NP‐SH) content has been studied in rats. There was a rapid, dose‐related increase in liver water which reached a maximum between 16 and 24 h after HCBD administration and then returned to control values by day 4. Associated with the increased water, there was an increase in the Na+ and K+ ions when related to the dry weight of the liver. However, the actual concentration of both cations in total liver water did not alter. The total liver DNA, protein or cytochrome P‐450 concentration did not change, at a time when there was a maximal increase in liver water. There was a rapid decrease in liver NP‐SH, which reached a nadir (50% of control) 8 h after HCBD administration, then increased to 150% of normal on day 5 and returned to normal by day 10. On histopathological examination, the liver appeared essentially normal, apart from a slight fatty change. Ultrastructural changes were, however, observed 8 h after dosing, when periportal hepatocytes contained occasional swollen mitochondria, whereas centrilobular hepatocytes appeared normal. By 16–24 h, mitochondrial swelling was marked in most periportal hepatocytes and some alteration in smooth endoplasmic reticulum was seen. It is suggested that HCBD or a metabolite causes disruption of mitochondria and this results in an influx of water into the cells. Normal concentrations of Na+ and K+ are, however, maintained by an intact Na+ pump.
Effect of chlorine dioxide and its metabolites in drinking water on fetal development in rats
Authors: Suh Duck H. , Abdel‐Rahman Mohamed S. , Bull Richard J. 
Published: October 2006

AbstractThe chlorination of surface waters is known to form trihalomethanes. Therefore, chlorine dioxide (ClO2) is being considered as an alternative disinfectant. This study was designed to determine the effect of chlorine dioxide and its metabolites, chlorite (ClO) and chlorate (ClO), on rat fetuses exposed in utero. Female rats were administered ClO2 at 0, 1, 10 and 100 mg 1−1 and ClO or ClO at 1 and 10 mg 1−1 daily in the drinking water for 2 1/2 months prior to and throughout gestation. Rats were killed on day 20 and fetuses examined for external, skeletal and visceral malformations. Slight decreases in weight gain during pregnancy were seen in the ClO2 administered groups. A significant dose‐response relationship in the decreases of the numbers of implants and live fetuses were observed in the ClO2 groups. Although there were increased incidences of resorptions in the ClO and ClO groups, no statistically significant increase was found in the groups. Fetal weight was significantly increased in the 100 mg 1−1 ClO2 group. Also, fetal length was increased in the 10 mg 1−1 ClO and ClO treatment groups. Skeletal defects, such as incompletely ossified or missing sternebrae, rudimentary ribs and incompletely ossified skull bones were increased in all treatment groups, but none were significantly different from the control group. A few cases of hypoplastic kidney, hydronephrosis and dextrocardia were observed in the treatment groups.
Subchronic feeding study in beagle dogs of N‐methylpyrrolidone
Authors: Becci Peter J. , Gephart Larry A. , Koschier Francis J. , Johnson William D. , Burnette Llewellyn W. 
Published: October 2006

AbstractThe potential toxicity of N‐methylpyrrolidone was evaluated following dietary administration for 13 weeks to male and female beagle dogs at dosage levels of 25, 79 and 250 mg per kg body weight per day. Body weight gain and food consumption, hematological and clinical chemical data, and ophthalmic, gross and histopathological examinations were used to study possible toxicological or pathological effects. No statistically significant treatment‐related effects that were judged to be biologically meaningful were seen in any parameters of either male or female animals exposed to N‐methylpyrrolidone at any dose level. However, a dose‐dependent decrease in body weight and increase in platelet count that correlated with increased megakaryocytes was observed. Serum cholesterol in males decreased with increasing doses.
The health hazards of formaldehyde
Authors: Wartew G. A. 
Published: October 2006

AbstractFormaldehyde is ubiquitous in the environment. As an aqueous solution, it causes burns on contact with the skin and eyes, and the vapour is irritating to the eyes and respiratory system. It is a sensitizing agent and may affect susceptible individuals at levels below the current British TLV of 2 ppm. It has been tested for teratogenicity in several animal species by a variety of routes, but was not positive in any of the studies. Inhalation of the vapour has been shown to cause nasal cancer in rats and mice. However, epidemiological studies have failed to confirm whether or not the compound is carcinogenic in humans.
The possibility of food contamination with cadmium by means of coloured plastics
Authors: Preda N. , Popa Letitia , Ariesan Maria 
Published: October 2006

AbstractBy using spectrophotometric atomic absorption, the release of cadmium from some plastic materials (polyethylenes, PVC, polystyrene) used for manufacturing containers, wraps and household objects (which are coloured with pigments derived from cadmium compounds) was studied. Subchronic experiments (45 days) were carried out in white Wistar rats with extracts from cadmium—containing plastic in comparison with the pigment alone. The excreted cadmium in urine and the activity of some serum enzymes were determined. Histopathological changes of the main internal organs were observed. It was found that some pigments of the Papion type have the property of releasing cadmium in amounts exceeding the admitted sanitary levels, amounts which proved to be toxic, producing enzymic and histopathological changes in kidneys and testes.
Percutaneous absorption of an antimicrobial organosilicon quarternary ammonium chloride in rabbits
Authors: Siddiqui Waheed H. , Malek James R. , Stanton E. , Hobbs E. J. 
Published: October 2006

AbstractThe percutaneous absorption of an organosilicon quaternary ammonium chloride (14C)‐3‐(trimethoxysilyl)‐propyldimethyloctadecyl ammonium chloride (14C‐Si‐QAC) was studied in rabbits. Aqueous solution of 14C‐Si‐QAC was either applied to the intact, clipped back of animals for 10 days or administered by a single intravenous dose. Urine and feces were collected at 24‐h intervals and tissue concentration of radioactivity was determined at the end of the 10‐day study period. Elimination of 14C‐Si‐QAC after parenteral administration was slow and occurred by both urine and feces (13.5% in urine and 20% in feces). No radioactivity was found in the urine of dermally treated animals. Tissue concentrations of 14C were highest in the liver, lung and kidneys after i.v. administration. None was detected in tissues of dermally treated animals. The results showed that the absorption of 14C‐Si‐QAC through the skin of the rabbit was essentially zero. The potential absorption hazard of the use of this antimicrobial agent in contact with the skin is therefore considered to be insignificant.
Pharmacokinetics of Alcide®, a germicidal compound in rat
Authors: Scatina Joann , Abdel‐Rahman Mohamed S. , Gerges Samy E. , Alliger Howard 
Published: October 2006

AbstractAlcide® is a germicidal compound which is currently being used as a liquid sterilizer. This agent has the ability to kill a wide range of bacteria, viruses and fungi in vitro within 1 min. The active ingredients in this sterilizer are sodium chlorite and lactic acid. The kinetics of 36Cl‐labelled liquid Alcide® were studied in rats. After oral administration, the peak plasma level was obtained in 8 h. The half life for 36Cl absorption from plasma was 8.03 h, corresponding to a rate constant of 0.086 h−1, while the half life for 36Cl elimination from plasma was 48.02 h, corresponding to a rate constant of 0.014 h−1. At 144 h, radioactivity was highest in plasma followed by lung, kidney, skin, bone marrow, stomach, ovary, duodenum, ileum, spleen, fat, brain, liver and carcass. The greatest amount of activity in whole blood was present in plasma. Subcellular distribution revealed that 85% of the activity in the liver homogenate resided in the cytosol. Seventy per cent of total activity in plasma was located in the trichloroacetic acid (TCA) supernant, with 30% bound to the precipitated protein fraction. Urinary excretion accounted for most of the 36CI eliminated. Radioactivity was excreted as chloride and chlorite in urine.
Carbon monoxide‐induced brain injury: Neurochemical studies after single and repeated exposures
Authors: Elovaara E. , Rantanen J. 
Published: October 2006

AbstractBiochemical effects of a single and once‐repeated exposure to carbon monoxide (0.2% CO, 30 min) were studied in mouse brain. The effect of the severity of the first exposure on the brain reaction to the second exposure (0.2% CO, 30 min) was also studied after exposure to four different CO doses (0.2% CO for 0, 2 or 5 h, and 0.3% CO for 2 h). 1. The DNA content of brain decreased after single and once‐repeated CO exposures. The effect of the second exposure was greater than that of the first. 2. The changes in the glycosphingolipid synthesis of brain were measured as the specific rate of precursor incorporation into the two isolated galactolipid fractions, i.e., cerebrosides and gangliosides following a 2‐h pulse‐labelling with 3H‐galactose in vivo. The synthesis of cerebrosides was substantially inhibited for a short period after the first and the second exposures. A late compensatory over‐ecovery of synthesis was found only after the second exposure. The rate of galactose incorporation into gangliosides was not immediately depressed after CO exposure, but otherwise the changes were similar to those of cerebrosides. 3. The protein, phospholipid and cerebroside contents of brain were also affected in parallel fashion with the changes of DNA content. The content of gangliosides was increased after the first, but not after the second exposure. The enhanced reaction of brain to the second CO poisoning suggests the existence of sublethal brain cell injury which is produced by the first CO exposure and manifested by altered reactions to the second exposure.
Toxicology studies with a stable intravenous formulation of nitroglycerin
Authors: Anderson J. A. , McGuire E. J. , Watkins J. R. , Fitzgerald J. E. , de la Iglesia F. A. 
Published: October 2006

AbstractThe preclinical toxicologic profile of Nitrostat, a stable parenteral formulation of nitroglycerin, was determined in mice, rats, rabbits and dogs. Single‐dose i.v. studies in rodents yielded LD50 values of 17.3 and 18.2 mg kg−1 in male and female mice, and 24.4 and 23.2 mg kg−1 in male and female rats, respectively. Subacute i.v. studies in rats at doses of 2.5, 5.0 and 10.0 mg per kg per day, and in dogs at doses 1.0 and 3.0 mg per kg per day for two weeks, elicited minimal reactions. In rats, suppression of body‐weight gain and food consumption occurred among treated and vehicle‐control animals. Mild tissue irritation at injection sites was noted in treated and vehicle‐control groups. There were no clearly drug‐related clinical or pathological findings in dogs. In rabbits, repeated intravenous administration of Nitrostat did not induce significant local venous irritation. The results of these studies indicated that the stabilized parenteral formulation of nitroglycerin did not elicit unusual toxic properties in intravenous infusion studies.
Genetic toxicology association—Fall Meeting 1982
Authors: Skinner Michael J. , Sega Gary A. , Butterworth Byron E. 
Published: October 2006

AbstractThe Fall Meeting of GTA was held on 4 November 1982 at Cherry Hill, New Jersey. The theme of the program was in vivo/in vitro assays for unscheduled DNA synthesis (UDS) detection. The meeting was attended by about 100 members who heard three invited speakers, Gary Sega, Byron Butterworth and Michael Skinner, give talks on various aspects of UDS. These were complimented in the afternoon by a series of four contributed papers. The following are abstracts of the talks given by the main speakers.
Rapid high‐performance liquid chromatographic method for the estimation of toxicological levels of 25‐hydroxycholecalciferol (25‐OH D3) in human serum
Authors: Łukaszkiewicz Jacek , Kozłowski Kazimierz , Lorenc Roman 
Published: October 2006

AbstractA reversed‐phase HPLC method for determination of 25‐hydroxycholecalciferol (25‐OH D3) in serum samples is described. The method involves extraction of 25‐OH D3 with hexane, followed by differential resolubilization in acetonitrile. The sample is then applied directly on the C18 bonded phase column of the liquid chromatograph, and developed in a acetonitrile‐water solvent system. In the range 12.5–400 ng, a linear relationship was observed between detector response and the amount of 25‐OH D3 placed on the column. Also, a very good correlation was observed between the amounts of 25‐OH D3 added to serum samples, and the calculated amounts. The method can be used for screening for toxicological levels of 25‐OH D3 in patients treated with high doses of vitamin D3.
The effect of chronic exposure to 100 ppm carbon monoxide on brain biomines, serum corticosterone and organ weights in rats
Authors: Vyskočil Adolf , Tušl Miloslav , Zaydlar Karel 
Published: October 2006

AbstractThe effect of chronic exposure to 100 ppm (0.01%) CO on pituitary‐adrenal activity was evaluated by measuring serum corticosterone and brain bioamine levels in the rat. Exposure to CO for 1 month induced a decrease in the brain serotonin levels. Serum corticosterone, brain dopamine and noradrenaline as well as the weight of the adrenal glands, lungs, spleen and liver were unchanged. After two months of exposure, serum corticosterone and brain serotonin levels were elevated and the liver weight was significantly lower. This suggests that at this chronic low concentration CO acts as a stressor, and the organism initiates a general defensive reaction. The effect of CO on the pituitary‐adrenal axis could be mediated by a central neuronal pathway.
Urinary excretion products after the administration of 14C‐acetaldehyde to rats
Authors: Kallama Seija , Hemminki Kari 
Published: October 2006

AbstractRats were injected with 120 μCi of 14C‐acetaldehyde containing carrier acetaldehyde, and the urinary excretion products were assayed by cation exchange chromatography, resolving five main peaks of radioactivity. Urine contained 6% of the dose of 14C‐acetaldehyde administered. The main urinary product of acetaldehyde, fraction 5, was produced via acetate. Acetate was also identified in the urine. Two cysteine adducts, probably isomeric metabolites of 2‐methylthiazolidine‐4‐carboxylic acid, were detected. They constituted about 2% of the radioactivity in the urine collected 48 h after the administration of 14C‐acetaldehyde. They appeared to retain a carboxylic group. When the reaction mixture of 14C‐cysteine and acetaldehyde was injected into a rat, the half‐lives of the two tiazolidine derivatives was 10 h. Only 13.6% of the radioactivity was detected in the urine suggesting ready metabolism of 2‐methylthiazolidine‐4‐carboxylic acid.