Showing papers in "Toxicological Sciences in 2000"

TL;DR: It is hypothesized that the phthalate esters that altered testis function in the pubertal male rat would also alter testisfunction in the fetal male and produce malformations of androgen-dependent tissues and, in summary, DEHP, BBP, and DINP all altered sexual differentiation, whereas DOTP, DEP, or DMP were ineffective at this dose.

TL;DR: Brominated flame retardants, especially the brominated phenols and tetrabromobisphenol A, are very potent competitors for T(4) binding to human transthyretin in vitro and may have effects on thyroid hormone homeostasis in vivo comparable to the thyroid-disrupting effects of PCBs.

TL;DR: The current study provides the most structurally diverse ER RBA data set with the widest range of RBA values published to date.

TL;DR: Data indicate that DEHP disrupts male rat sexual differentiation by reducing T to female levels in the fetal male rat during a critical stage of reproductive tract differentiation.

TL;DR: In vivo studies indicated that the 3-day uterotrophic assay in prepubertal rats was the best method for detecting estrogenic activity when compared with all other end points, based upon the dose-response data for ethynyl estradiol and 4-tert-octylphenol.

TL;DR: Intratracheal instillation can be a useful and cost-effective procedure for addressing specific questions regarding the respiratory toxicity of chemicals, as long as certain caveats are clearly understood and certain guidelines are carefully followed.

TL;DR: The purpose of this review is to assess the literature currently available on the molecular effects of acrolein, to discuss the relationship between effects on glutathione with those on various genes, and to present some new data showing that ac rolein actively stimulates genes associated with the electrophile response element.

TL;DR: For this 10-day prenatal (embryonic and fetal) exposure to DBP, the NOAEL and LOAEL (lowest-observed-adverse-effect level) were 50 and 100 mg/kg/day, respectively, this is currently the lowest NoAEL described for the toxicity of DBP.

TL;DR: A route dependency of BPA bioavailability in rats is demonstrated, with oral administration resulting in the lowest bioavailability, and explanation for the apparent route differences in estrogenic potency observed for BPA is offered.

TL;DR: The observed induction of aromatase, the rate-limiting enzyme in the conversion of androgens to estrogens, may be an underlying explanation for some of the reported hormonal disrupting and tumor promoting properties of these herbicides in vivo.

TL;DR: It is demonstrated that atrazine alters LH and prolactin serum levels in the LE and SD female rats by altering the hypothalamic control of these hormones.

TL;DR: The present studies demonstrate a general application of toxicogenomics that distinguishes two mechanistically unrelated classes of toxicants (cytotoxic anti-inflammatory drugs and DNA-damaging agents) based solely upon a cluster-type analysis of genes differentially induced or repressed in cultured cells during exposure to these compounds.

TL;DR: The results indicate that ATR delays puberty in the male rat and its mode of action appears to be altering the secretion of steroids and having subsequent effects on the development of the reproductive tract, which appear to be due to ATR's effect on the central nervous system.

TL;DR: The results demonstrated that the metabonomic approach could readily distinguish the onset and reversal of toxicity with good agreement between clinical chemistry and PCA data, and support the contention that the metabolism approach represents a promising new technology for the development of a rapid throughput in vivo toxicity screen.

TL;DR: The inflammation observed after acetaminophen overdose may be characteristic for a response sufficient to recruit neutrophils for the purpose of removing necrotic cells but is not severe enough to cause additional damage.

TL;DR: This work considers the potential contribution that individual epitopes may make to the allergenicity of a protein, and considers the effects that resistance to proteolysis, post-translational glycosylation, and enzymatic activity may have.

TL;DR: The hypothesis that linuron is an AR antagonist both in vivo and in vitro is supported, but it remains to be determined if linuron alters sexual differentiation by additional mechanisms of action.

TL;DR: The utility of modeling approaches as one component for better integration of physicochemical and biological properties into risk assessment is considered, and the potential for both environmental and human health effects of chemicals and their interactions is considered.

TL;DR: The results suggest that the AhR may play a role in the formation of primordial follicles and the regulation of antral follicle numbers.

TL;DR: The inhibition of the roten one- and atractyloside-induced apoptosis and mitochondrial dysfunction by cyclosporin A suggests the MPT may be involved in the induction of apoptosis by rotenone.

TL;DR: The observation that genotoxic effects in alveolar epithelial cells occurred only after crystalline but not amorphous silica exposure, despite a high degree of inflammatory-cell response after subchronic exposure to both types of silica, suggests that in addition to an inflammatory response, particle biopersistence, solubility, and direct or indirect epithelial cell cytotoxicity may be key factors for the induction of either mutagenic events or target cell death.

TL;DR: A human breast cancer cell line, MCF-7, transiently transfected with a chimeric estrogen receptor and a luciferase reporter plasmid, was used to investigate the estrogenic activity of benzo[a]pyrene, a prototypical polyaromatic hydrocarbon (PAH), suggesting that 7,8-OH B,[a]P was being further metabolized to one or more cytotoxic metabolites.

TL;DR: DEHP exposure exacerbated age-, species- or strain-related lesions such as mineralization of the renal papilla and chronic progressive nephropathy in male rats, and may respond differently depending on the potency of the peroxisome proliferator.

TL;DR: The data indicate that the reproductive system of the fetal male rat is most sensitive to antiandrogenic effects of vinclozolin, although effects are more severe and 100 % of male offspring are affected with administration of v inclozol from GD 14 through GD 19.

TL;DR: The data show that ATR can delay the onset of puberty and alter estrous cyclicity in the female Wistar rat ( NOAEL of 25 mg/kg).

TL;DR: It is suggested that JP-8 penetration will not cause systemic toxicity because of low fluxes of all the components; and the absorption of aliphatic components into the skin may be a cause of skin irritation.

TL;DR: Accumulation of MC and subsequent changes in cellular morphology, PP inhibition, and hepatocyte necrosis represent the primary events in microcystin induced hepatotoxicity and appear to be associated with the reversible interaction of MC with the PP.

TL;DR: It is demonstrated that at toxicologically relevant concentrations, most but not all bile acids alter mitochondrial bioenergetics, so impairment of mitochondrial function can be clinically relevant for patients with cholestasis.

TL;DR: Chronic inorganic As exposure produced injuries to multiple organs, and MT-null mice are generally more susceptible than WT mice to As-induced toxicity regardless of route of exposure, suggesting that MT could be a cellular factor in protecting against chronic As toxicity.

TL;DR: The finding of the TCDD-hyperinsulinemia relationship is consistent with studies of Vietnam veterans and suggests that high blood T CDD levels may cause insulin resistance.