bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design and evaluation of an exhaled breath sampler for biological monitoring of organic solvents
Authors: Periago J. Francisco , Luna Aurelio , Morente Antonio , Zambudio Alfonso 
Published: October 2006

AbstractWe designed a breath sampler based on a tube which collects the final portion of exhaled air. The passage of successive fractions through a layer of activated charcoal is controlled by a three‐way valve. This system was validated in a controlled atmosphere of n‐hexane and toluene at four concentrations between 12 and 110 mg m−3 and 12 and 115 mg m−3, respectively. Uptake volumes of 0.1, 0.2 and 0.3 I were tested at relative humidities of 46% and 98%. There were no significant differences in the recoveries obtained under any of the conditions tested. We confirmed the reproducibility between successive samples in volunteers and exposed workers, and found no significant differences between the different sampling conditions studied. Our system enriches the sample in an adsorbent cartridge by collecting successive fractions of end‐exhaled breath from one or more exhalations until the amount required by the analytical method has been accumulated. It is portable, economical and highly operative in the field.
Subacute oral toxicity of 2‐butyne‐1,4‐diol in rats
Authors: Jedrychowski Ryszard A. , Czajkowska Teresa , Gorny Roman , Stetkiewicz Jan , Stetkiewicz Irena 
Published: October 2006

Abstract2‐Butyne‐1,4‐diol was given to male and female Wistar Imp:DAK rats by oral gavage for 28 consecutive days in daily doses of 1, 10 or 50 mg kg−1 day−1. After 28 days all animals were necropsied. Blood samples were obtained and selected organs were weighed and prepared for histological examination. Treatment‐related effects in the high‐dose group consisted of: fatal cases in both sexes; depressed body weight gain in males; increase of absolute and/or relative weights of liver and kidneys in both sexes; decreased red blood cell count, haematocrit value and haemoglobin concentration in female rats and elevated reticulocyte count and leukocyte count in both sexes; increased total serum protein content in females, elevated glucose concentration in males and higher activity of sorbitol dehydrogenase in both sexes; and hisiopathological evidence of hepatotoxicky and nephrotnxicity in decedents, and hepatic and splenic changes in survivors. Minor hepatic, splenic and erythrocytic changes were also found in some females given the middle dose. The dose of 1 mg kg−1 day−1 was considered to be the no‐observed‐effect level (NOEL), and 10 mg kg−1 day−1 the lowest‐observed‐eflfect level (LOEL).
Mechanism of citrinin‐induced dysfunction of mitochondria. I. Effects on respiration, enzyme activities and membrane potential of renal cortical mitochondria
Authors: Chagas Generoso M. , Campello Annibal P. , Klüppel Ma. Lúcia W. 
Published: October 2006

AbstractCitrinin depresses the phosphorylation efficiency of rat renal cortical mitochondria, as inferred from the decrease of the respiratory control coefficient (RC) and ADP/O ratios. The transmembrane potential (Δψ) developed by energized mitochondria and the depolarization upon ADP addition are also decreased. Citrinin (1.0 mM) inhibits almost all enzymes linked to the respiratory chain and increases the activity of succinate cytochrome c reductase and succinate oxidase (coupled). Malate and glutamate dehydrogenases are also inhibited. The inhibitory action of citrinin on phosphoryiation efficiency could be related to the following findings: the effect on complex I; the action on the ATP synthetase complex; the partial inhibition of the transmembrane potential.
Experimental design‐based quantitative structure—toxicity relationship of some local anaesthetics using the PLS method
Authors: Norinder Ulf 
Published: October 2006

AbstractA quantitative structure‐toxicology (LD50) relationship for some N‐alkylsuccinimides is presented. The relationship is based on a small and carefully selected training set using experimental design methodology. The good predictability, an overall r2 value of 0.75, with such an approach is demonstrated. Factors such as large N‐alkyl groups, substitution in the aromatic ring and a long side chain between the two nitrogens are favourable for low toxicity.
Embryolethality and teratogenicity of butyl benzyl phthalate in rats
Authors: Ema Makoto , Itami Takafumi , Kawasaki Hironoshin 
Published: October 2006

AbstractPregnant Wistar rats were given butyl benzyl phthalate (BBP) at a dose of 2.0% in the diet on days 0–20, days 0–11 or days 11–20 of pregnancy. Food consumption and body weight gain were decreased in pregnant rats given BBP. Pre‐implantation loss in the BBP‐treated groups was comparable to that in the control and pair‐fed groups. All dams given BBP on days 0–20 or days 0–11 exhibited complete resorption of all the implanted embryos. No increase in post‐implantation loss was found in pregnant rats given BBP on days 11–20. Marked teratogenicity was detected in fetuses of the dams given BBP on days 11–20. Cleft palate and fusion of the sternebrae were predominantly observed. Seventy‐two of the 134 fetuses had a cleft palate. The incidence of malformations in this group was significantly and markedly higher than that in the control and pair‐fed groups. In conclusion, the administration of BBP during the first and second half of pregnancy produced embryolethality and teratogenicity, respectively.
Indirect and lactation‐associated changes in renal alkaline phosphatase of newborn rats prenatally exposed to cadmium chloride
Authors: Saillenfait A. M. , Payan J. P. , Ban M. , de Ceaurriz J. 
Published: October 2006

AbstractPregnant Sprague‐Dawley rats were intraperitoneally injected with physiological saline solution (vehicle) or cadmium chloride (CdCl2) at 2.5 mg kg−1 body wt. on days 8, 10, 12 and 14 of gestation. Offspring were examined for renal alkaline phosphatase activity (ALP) on postnatal days (PND) 3 and 12, and for kidney metallothionein (MTh) and for liver, kidney and entire gastrointestinal tract 109Cd content at birth and on PND 3 and 12. No effects were observed on neonatal survival or on body, liver and kidney weights of pups up to PND 12. Newborns born and fed by mothers exposed to CdCl2 during pregnancy exhibited a significant decrease in ALP activity on PND 3. Conversely, no significant changes were observed in newborns lactatcd by surrogate non‐treated mothers. Renal MTh increased with age but was not influenced by maternal treatment. Traces of 109Cd were present in the liver at birth (5–7 ng). Thereafter, 109Cd was mainly found in the gastrointestinal tract of newborns lactated by their biological mothers (610–690 ng on PND 12), with a marginal uptake in the liver (10–12 ng on PND 12). 109Cd was not detectable in the kidneys at any age (< 4 ng).These results show that prenatal exposure to Cd cannot be the sole aetiological agent in the induction of the subtle and transitory changes in renal biochemistry observed in offspring born and fed by female rats intraperitoneally injected with 2.5 mg CdCl2 kg−1 body wt. on days 8, 10, 12 and 14 of gestation. The resofts also contradict the role of a direct effect on the kidney.
The local lymph node assay: Results of a final inter‐laboratory validation under field conditions
Authors: Scholes E. W. , Basketter D. A. , Sarll A. E. , Kimber I. , Evans C. D. , Miller K. , Robbins M. C. , Harrison P. T. C. , Waite S. J. 
Published: October 2006

AbstractThe local lymph node assay (LLNA) assesses the sensitizing activity of chemicals by measurement of primary lymphocyte proliferation in lymph nodes draining the site of application. In this final inter‐laboratory stady the consistency of LLNA results between laboratories and with guinea pig maximization test (GPMT) data was examined under ‘field’ conditions. Nine chemicals were evaluated independently by each laboratory according to guidelines for test concentration and vehicle selection developed during previous validation studks to ensure assay optimization. Equivalent predictions of sensitization potential were obtained by all laboratories for eight chemicals. Five of seven chemicals identified as sensitizers in the GPMT were correctly identified in the LLNA—four by all laboratories and 1 (4‐chloroaniline) by one laboratory only—although in this latter case, two other laboratories obtained clear dose responses, suggestive of sensitization. The LLNA identified correctly those chemicals predicted to be extreme or strong sensitizers in the GPMT. The remaining two chemicals were non‐sensitizers in the guinea pig and failed to elicit positive proliferative responses in the LLNA. These data demonstrate that sensitivity and reliability of the LLNA is retained when chemicals are evaluated independently, and that it provides a reliable pre‐screen for the identification of chemicals with significant sensitization potential.
The effect of a commercial 2,4‐d formulation on chemical‐ and viral‐induced tumor production in mice
Authors: Blakley B. R. , Gagnon J. M. , Rousseaux C. G. 
Published: October 2006

AbstractMale CD‐1 mice were exposed to a commercial formulation of 2,4‐dichlorophenoxyacetic acid (2,4‐D), the amine derivative, in the drinking water at concentrations ranging from 0 to 0.163% of the formulated product, equivalent to approximately 0–50 mg kg−1 day−1 2,4‐D content. The effect of 2,4‐D on urethan‐induced pulmonary adenoma formation was evaluated following a 105‐day exposure. Urethan‐induced sleeping times observed following an i.p. injection of urethan (1.5 mg g−1) after 3 weeks of 2,4‐D exposure were not altered by 2,4‐D, indicating that 2,4‐D did not influence urethan elimination. Pulmonary adenoma production, which was evaluated 84 days after urethan injection, was enhanced by 2,4‐D exposure but had no effect on tumor size. The effect of 2,4‐D on the incidence of spontaneous murine lymphocytic leukemia was evaluated during the 365‐day treatment period. Mortality associated with the leukemia virus was not altered by 2,4‐D treatment. Exposure to this commercial 2,4‐D product at moderately high levels of exposure may modify the development or expression of certain tumors in CD‐1 mice. The mechanism of the co‐carcinogenic or tumor‐promoting activity associated with 2,4‐D exposure remains to be determined.
Development and validation of a highperformance liquid chromatographic method for the determination of benzophenone‐3 in rats
Authors: Abdel‐Nabi Ismail M. , Kadry Abdelrazak M. , Davis Richard A. , Abdel‐Rahman Mohamed S. 
Published: October 2006

AbstractA precise, accurate, selective and sensitive liquid chromatographic method for the determination of benzophenone‐3 in rat biological fluids and different tissues has been developed. The minimum detection limit for benzophenone‐3 was 2.0 ng ml−1 and the retention time was 6.01 min. Standard curves for benzophenone‐3 were linear in a wide range of concentrations in methanol and different body fluids, ranging from 6.25 ng ml−1 to 100 μg ml−1. To detect benzophenone‐3 in rat whole blood after oral administration, HCl hydrolysis was required. Benzophenone‐3 was found to produce a peak blood concentration 1 h after administration. Free benzophenone‐3 in urine represented a very small percentage during the first 12 h after administration, while a higher concentration of the glucuronide conjugate was detected in the same time period.
Acute and subacute toxicity of 7.5% hypertonic saline/6% dextran‐70 (hsd) in dogs 1. serum immunoglobulin and complement responses
Authors: Summary James J. , Dubick Michael A. , Zaucha Gary M. , Kilani Ahmed F. , Korte Don W. , Wade Charles E. 
Published: October 2006

AbstractClinical use of modern dextran solutions has been limited by concerns of anaphylactoid reactions. To assess the short‐term antigenic response to 7.5% hypertonic saline in 6% Dextran‐70 (HSD), sera were obtained from dogs involved in the acute and subacute toxicology testing of HSD and its individual components, and analyzed for IgG, IgM and C3 complement. In separate studies, beagles were infused i.v. with a single dose of HSD or its components at 20 ml kg−1 (the maximum tolerated dose; MTD), or the MTD daily for 14 days, and serum was obtained prior to and at various times after infusion up to 14 days. In both studies, despite serum dextran concentrations exceeding 2000 mg dl−1, no induction of IgG, IgM or C3 complement concentrations were observed. In addition, serum IgG immunoelectrophoretic patterns were of normal curvature, position and intensity; the immunoprecipitin bands were not displaced, bowed, inhibited or thicker than the normal preinfusion immunoelectrophoretograms.The data suggest that single or multiple HSD i.v. injections, as much as five times the proposed therapeutic level for the treatment of hypovolemia, evoked no increase in antibody titers in dogs. Therefore, therapeutic use of HSD in the treatment of hemorrhagic shock should not be associated with widespread concomitant allergic complications.
Mutagenicity studies on two triphenylmethane dyes, bromophenol blue and tetrabromophenol blue
Authors: Lin George H. Y. , Brusick David J. 
Published: October 2006

AbstractBromophenol blue and tetrabromophenol blue are two triphenylmethane dyes. Triphenylmethane derivatives and their structurally related compounds, such as fluoresceins and xathenes, are widely used as industrial dyes for foods, drugs, cosmetics, textiles, printing inks or laboratory indicators. Since a number of these types of dyes have been reported to be genotoxic, safety concerns on these two dyes of interest have been raised. Consequently, a battery of genetic toxicology assays, including the Ames Salmonella/microsome assay, L5178Y TK+/− mouse lymphoma assay, mouse micronucleus test and mitotic recombination assay with yeast Saccharomyces cerevisiae strain D5, has been performed on each of the two dyes. The results of the evaluations indicate that both bromophenol blue and tetrabromophenol blue were not active and can be considered non‐genotoxic for the three genetic endpoints assessed (gene mutation, chromosome aberrations and primary DNA damage). Genetic activities in some structurally related compounds of these dyes have been reported but may be attributed to the presence of mutagenic impurities rather than the compound itself.
The influence of fenarimol on dna synthesis and mitotic activity in rat liver
Authors: Palut Danuta , Ludwicki Jan , SzlȩLzak‐Kopeć Joanna 
Published: October 2006

AbstractFenarimol administered in one single oral dose of 125 or 62.5 mg kg−1 body wt. day−1, respectively, stimulated rat liver enlargement at a dose‐independent rate. Three single doses of fenarimol produced dose‐dependent liver growth, whereas five single doses caused no further increase in liver weight. This increase was accompanied by an increase in hepatic DNA synthesis and mitotic activity, with a peak on the first day after the beginning of the experiments. The increase in binuclear hepatocytes and signs of necrosis suggested that the hepatomitogenic effect reflected a compensatory hyperplasia. After both three and five single doses the hepatomitogenic effect was supressed, as a result of tolerance development.
Effects of nickel hydroxycarbonate on alveolar macrophage functions
Authors: Arsalane K. , Aerts C. , Wallaert B. , Voisin C. , Hildebrand H. F. 
Published: October 2006

AbstractThe metabolic effects of different concentrations of nickel hydroxycarbonate (NiHC) on guinea pig alveolar macrophages (GPAMs) were investigated. Exposure to high concentrations of NiHC (6.25 and 12.5 μg 10−6 cells) led to cell vacuolization. Morphological changes were associated with a dramatic reduction in the steady‐state level of cellular adenosine triphosphate (ATP), i.e. ATP levels were reduced by 35% (P < 0.001) and 53% (P < 0.01), respectively. Low concentrations of NiHC (0.0625 and 0.125 μg 10−6 cells) did not induce morphological changes but increased cellular ATP content by 19% (P < 0.01) and 12% (P < 0.05), respectively. Effects of NiHC (0.125 and 6.25 μg 10−6 cells) on cell oxidative metabolism were studied. The chemiluminescence was significantly increased (P < 0.001) by the lower but not the higher concentration. A slight inhibition of total superoxide dismutase (P < 0.05) and a decrease of catalase activity were demonstrated (P < 0.05) for the high dose, while the low dose decreased the levels of reduced and total glutathione. In conclusion, the effects of NiHC on alveolar macrophages are characterized by an overproduction of free radicals for low concentrations and the depletion of cellular reserve energy, particularly ATP, for high concentrations.
Preliminary report on the use of zinc in vivo to protect against nitrogen mustard toxicity in female Balb/cJ mice
Authors: Shackelford Mary E. , Tobey Robert A. 
Published: October 2006

AbstractPrevious studies with cultured normal human fibroblasts indicated that treatment of cells with zinc before exposure to an alkylating agent enhanced cell survival by seven‐ to ninefold. To establish whether a similar zinc‐induced protective response could be elicited in vivo, we conducted a preliminary experiment in which Balb/cJ female mice were treated with zinc (2 mg kg−1 body weight) or saline by intraperitoneal (i.p.) injection at 48, 36, 24 and 12 h before i.p. administration of the alkylating agent nitrogen mustard (4 mg kg−1 body weight). Of the animals that received saline before nitrogen mustard, 57% died as compared with only 20% in the group treated with zinc before administration of the alkylating agent. As was observed in the studies of cells in culture, the results described in this report may suggest the existence in Balb/cJ female mice of a zinc‐mediated protective response against nitrogen mustard toxicity.
Evaluation of the dermal carcinogenicity of lubricant base oils by the mouse skin painting bioassay and other proposed methods
Authors: Chasey K. L. , McKee R. H. 
Published: October 2006

AbstractLubricant base oils are petroleum products that are predominantly derived from the vacuum distillation of crude oil. Various types of refinement can be employed during the manufacturing process, and evidence suggests that certain of the associated process streams produce skin cancer. Polycyclic aromatic compounds (PACs), some of which are considered as the causative agents, are removed, concentrated or chemically converted during the refinement process. In order to understand the effects of various types of refinement processes on carcinogenic potential, 94 oils were evaluated in the mouse epidermal cancer bioassay. This Exxon database is unique, because of the wide range of crude oils and processing histories represented. Seven processing history classifications are described, and conclusions concerning the impacts of each refinement process on dermal carcinogenicity are discussed.This research also included an evaluation of selected biological and chemical test methods for predicting carcinogenic potential. These included a modified version of the Ames test for mutagenicity, as well as analytical characterizations of the polycyclic aromatic structures in the oils. For classification purposes, a sample was considered to be carcinogenic if it resulted in the production of two or more tumor‐bearing animals (in test groups of either 40 or 50 animals). The modified Ames test was considered to be positive if the mutagenicity index was ≥ 2.0, and PAC analyses were similarly designated as positive or negative according to proposed guidelines. All of the alternative test methods showed similar agreement with dermal carcinogenicity bioassay data; concordance values were ≥ 80%. However, each test was incorrect in ca. 10%–20% of the cases evaluated. Thus, while these methods may have great value as screening tests, the results should not be used in preference to dermal carcinogenicity data for hazard identification or labeling purposes.
Early cytotoxic effects induced by bis‐chloroethyl sulphide (sulphur mustard): [Ca2+]i rise and time‐dependent inhibition of B77 fibroblast serum response
Authors: Hua A. , Daniel R. , Jasseron M. P. , Thiriot C. 
Published: October 2006

AbstractEarly cytotoxic events were studied on B77 fibroblasts. Cells were treated with sulphur mustard (SM) in short‐term experiments in which cell viability was unchanged, as evaluated by the neutral red cytotoxicity test. This treatment was correlated to two early signs of cytotoxicity. The intracellular Ca2+ concentration [Ca2+ ]i level in SM‐treated Fura‐2‐loaded fibroblasts showed a significant dose‐dependent increase. This observed rise was sustained, in contrast to the Ca2+ signal induced by serum, and was already visible 5–10 min after the addition of SM to cell suspensions in vitro. Modification of the extracellular Ca2+ concentration in the medium had no effect on the cytosolic calcium rise caused by SM, suggesting release from intracellular Ca2+ pools. Furthermore, a time‐dependent inhibition of the [Ca2+ ]i transient increase induced by growthfactors (as evaluated by the fetal calf serum (FCS) response) was observed within the first hour of exposure. These latter results suggest that early alterations of calcium distribution induced by SM could be one of the earliest markers of SM intoxication.
S‐adenosyl‐L‐methionine prevents and reverses erythrocyte membrane alterations in cirrhosis
Authors: Muriel Pablo 
Published: October 2006

AbstractTransmethylation is an important means of altering the biological activity of a wide variety of compounds. In human and experimental CCI4‐liver cirrhosis the intrahepatic content of S‐adenosyl‐L‐methionine (SAM), an active methyl donor, and the SAM‐transmethylase activity are markedly reduced. Previously, it has been reported that SAM administration preserves hepatocyte plasma membrane Na+/K+‐ATPase and Ca2+‐ATPase activities in cirrhotic rats. Therefore, the aim of this work was to study the effect of SAM administration on the membrane lipid composition and the ATPase activity on erythrocytes derived from CCI4‐cirrhotic rats. Male Wistar rats were used in these experiments. In group 1, cirrhosis was induced by i.p. administration of CCI4. Animals of group 2 received, in addition to CCI4, three daily doses of SAM (20 mg kg−1, i.m.). Group 3 consisted of cirrhotic animals that, after 8 weeks of CCI4 treatment, received SAM (20 mg kg−1, i.m., three times daily) for 4 weeks without discontinuation of CCI4. Group 4 included animals treated with SAM alone. Seventy‐two hours after the end of treatment the rats were anaesthetized, blood was collected by heart puncture and the erythrocyte plasma membranes were isolated. The Na+/K+ ‐and (Ca2+ + Mg2+)‐ATPase activities and the cholesterol (CH) and phospholipid (PL) contents were determined in the plasma membranes. The Na+/K+ ‐ and Ca2+ ‐ATPase activities were both significantly decreased (twofold) in the CCI4‐treated group as compared to controls. Administration of SAM completely prevented this fall in both ATPases. In group 4, the Na+/K+ ‐ATPase activity was partially restored but the Ca2+‐ATPase activity was completely restored. CCI4 increased the CH/PL ratio; however, this alteration was not observed in the group treated with CCI4+ SAM simultaneously and was completely reversed in group 4. Since the increase in the membrane CH/PL ratio decreases the membrane fluidity and thus changes the enzyme activity, two mechanisms by which SAM preserves the ATPase activity in cirrhotic rats could be by preventing the increase in the CH/PL ratio and by methylation of phospholipids.