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Research regarding the phototoxicity of fenofibric acid on polymorphonuclear cells is given. By using a sensitive in vitro test, the researchers were able to detect phototoxic effects at minor concentrations previously undetectable.

Research regarding the effects of Hepatoprotective effects of cyproterone acetate in mice is given. By using cyproterone acetate pretreatments the researchers found that the effects of cadmium on mice was modified.

Research into detection processes of the autooxidation of adrenolutin as a step in catecholamine metabolism is given.

Research into the toxic mechanisms of cadmium exposure on cardiac tissue is given. The research shows that some exposure to cadmium may cause metabolic pathway alterations.

Research into the effects of repeated exposure to 5-vinyl-2 norbourne are given. The nine day study showed increased liver weights.

The effect of Vitamin E on sodium arsenate-induced ovarian steroidogenic function and gonadotrophin plasma levels in mature Wistar-strain albino rats is discussed. The results are intended to evaluate the physiological aspects of the arsenic levels in drinking water in parts of West Bengal in India.

A study of the toxicity of nickel on heart tissue is provided.

The genotoxic potential of 2,4-penatanedione in vivo and in vitro on mice and rats is discussed.

This study of 5-Aza-2'-deoxycytidine (d-AZA) on mice shows temporally-related defects including hindlimb phocomelia.

This study looks at the survival of diazotrophic bacteria in crude oil contamination.

This study looks at the cellular mechanisms disturbed during liver diseases such as cholestasis and mitochondrial dysfunction.

This study looks at the effects of dimethoate, an organophosphorus pesticide, on hematological and immunological parameters in mice.

A variety of environmental substances have been linked to estrogenic activity; e.g., poylychlorobiphenyls, pesticides, and pharmaceutical agents. The U.S. Environmental Protection Agency has formed an advisory committee to screen and tests some of the 87,000 chemicals which may act as hormonally active environmental substances and present a danger for endocrine disruptions in humans and animals.

Chromium (Cr) is highly carcinogenic and has been spread throughout the environment by a variety of industries. Iron and quinones have been shown to accelerate Cr(VI) reduction and may, therefore, have a role in influencing cytotoxic damage.

Laboratory tests have demonstrated the weak estrogenic effects of butyl benzyl phthalate (BBP), a chemical in wide use as a plasticizer in resins. Both BBP and its primary monoester metabolites have been been shown to activate the uterine growth of immature female rats.

Herbicides Paraquat, Dinoseb, and 2,4-D are studied for effects on liver mitochondrial bioenergetics and hepatic cells.

Verapamil, diltiazem, and nifedipine interactions involved in the effects of lead acetate on mice were studied.

The reaction of the nitrogen-fixing bacterium Azotobacter vinelandii to the metals silver, crude oil, mercury, and fenton reagent, which were introduced to its environment, was observed.

Research was conducted to investigate the effects of testosterone on cadmium-induced c-myc and c-jun expression, cytotoxicity and metallothionein (MT) synthesis in rat myoblasts (L6) cells. Testosterone was found to greatly enhance cadmium-induced accumulation of c-myc and c-jun transcripts in L6 cells, indicating enhanced oncogene expression. The effects were independent of changes in cadmium-induced cytotoxicity or MT expression. These results suggest implications for cadmium carcinogenesis.

Rats were treated with tap water containing various doses of lead acetate for 24 days to investigate the the long-term lead-induced toxic effects on the structure of rat submandibular glands. Results indicated that lead treatment can reduce exocytosis processes through the reduction in cell energy level and destruction of rough endoplasmic reticulum or mitochondria. However, there were no indications of any change in nuclear morphology.

The effects of lead acetate exposure on the morphine withdrawal syndrome in mice were investigated. The lead acetate levels in the drinking water of the experimental group were 0.05% and 0.1% and the control groups were administered with sodium acetate solution for seven, 14, 21 or 28 days. Jumping behavior on morphine-dependent and nondependent mice were observed. It was discovered that lead exposure interfered with the dopaminergic and adrenergic functions involved in the withdrawal syndrome. The jumping behavior was reduced by sodium acetate.

A study was conducted on the effects of toluene and trichloroethylene on the liver and kidney functions observed in rats after microsomal induction with phenobarbital. The two substances are used as industrial solvents and occupational exposure to them produce various health problems. Results revealed that phenobarbital contributed to the necrotizing effects of toluene and exerted a partial modulating effect against trichloroethylene. Toluene and trichloroethylene both induced the activities of serum transaminases and phenobarbital increased the excretion of creatinine.

Investigations into the thallium toxicity mitigating effects of cholinergic enzymes in the autonomic nervous system showed that such a mitigating effect is evident only in acute thallium exposure and in repeated minor thallium exposure. Repeated major exposure to thallium induces death in subjects. Repeated minor thallium exposure showed an increase in acetyl cholinesterase activity the midbrain regions and the striatum, which is also the case in single acute exposure.

Investigations into the physiological effects of inhaled red phosphorus smoke among four small mammal groups showed that phosphorus smoke inhalation poses a wide range of toxicity for the mammals. Immediately affected were guinea pigs, which reacted at a 1h-LC50 of 61mg per cu. m., with rabbits showing the highest tolerance at 1689 mg per cu. m. Histopathological studies showed that phosphorus smoke inhalation induces respiratory tract injury consistent with the inhalation of corrosive substances, as evident in the laryngotracheal epithelial or mucosal necrosis.

A critical review of literature on the cadmium toxicity-mitigating effects of steroids in rodents show that the induction of metallothionein is responsible for the cadmium toxicity-mitigation. Metallothionein is a cadmium-binding protein that is surmised to be one of the pathways for cadmium tolerance in rodents. Cadmium toxicity expresses itself greatly in the liver, both in chronic and acute exposure incidents.

Acute and chronic exposure to nickel monosulfide can lead to the growth of tumor in skeletal muscles. Nickel has been known to have carcinogenic effects on the human body particularly on the muscles. Furthermore, nickel deposition also has adverse effects on the liver, pancreas and bone-forming tissues. Nickel markedly increased the serum enzyme levels such as alanine transaminase (ALT), amylase and alkaline phosphatase (ALP). Increased ALT level indicate liver disease while ALP levels are useful for the clinical diagnosis of both liver and osteogenic disorders. Increased serum amylase levels reflect pancreatic damage.

Cattles grazing on endophyte-infected fescue grass have been found to have reduced milk production.Toxic fescue affect serum prolactin (PRL) which is involved in mammary development, lactation, body temperature, steroid hormone production and feed and water intake. Fescue particularly changes the functions of the hypophyseal and hypothalamic tissues involved in the production and regulation of PRL. Serotonin and thyrotropin releasing hormones elevates PRL levels while prolactin is suppressed by dopamine. Other manifestations of fescue toxicity include reduced feed intake, rough hair coat, weight loss, hyperthermia, excessive thirsting and urination.

Rubidium affects the secretory function of rat's submandibular gland. Mice treated with rubidium were found to have increased level of saliva protein and calcium concentrations. Secretion of N-acetyl-beta-D-glucosaminidase (NAG), a hydrolytic lysosomal enzyme produced after sabmandibular gland damage, was also enhanced among rubidium-treated mice. On the other hand, salivary flow rate was markedly decreased after introduction of rubidium.

Trichloroethylene (TRI) is an industrial chemical suspected of causing cancer among humans. Some studies associate the occurrence of urinary-tract tumors and lymphomas among laborers to TRI exposure. Exposure to such chemical has also been linked with childhood leukemia, renal injury and renal tumors. In 1995, the International Agency for Research on Cancer has reclassified TRI from 'not suspected as a human carcinogen' chemical to 'probably carcinogenic to humans' chemical.

An industrial chemical called 5-ethylidene-2-norbornene (ENB) was found to be incapable of inducing a mutagenic or clastogenic activity. ENB failed to produce mutagenic activity with or without metabolic activation from a Salmonella typhirium reverse assay with TA98, TA100, TA1535, TA1537 and TA1538 strains. Such result also holds for a Chinese hamster ovary (CHO) cell forward gene mutation assay (HGPRT locus), a sister chromatid exchange test and a cytogenic study.

Antiandrogen cyproterone acetate (CA) affects the toxicokinetics and toxicity of cadmium and the induction of metallothionein (MT) in C57 and C3H mice. Mice that are sensitive (C3H) and resistant (C57) to toxic effects of cadmium were found to have reduced level of cadmium in the liver 24 hours after receiving CA pretreatment. Such reduction in the level of cadmium results to an associated reduction in the level of cadmium-induced metallothionein in the liver of C57 and C3H mice.

Tissue distribution, absorption and elimination of bis[2-(dimethylamino)ethyl] ether or C-DMAEE,in four male groups of Fischer 344 rats during and for 48 hours, a 4-hour head-only exposure to DMAEE vapor are studied. The DMAEE vapor was readily absorbed at a constant rate, slowly discharged primarily by urinary excretion, and without preferential specific tissue or organ accumulation. Comparative findings of the study recommends that, qualitatively, DMAEE is pharmacokinetically handled in a related manner by percutaneous and inhalation routes.

The limited expression and lack of activation of the metallothionein (MT) gene in the major lobes of Wistar rat prostate and testes under normal circumstances and after exposure to hepatic boosters is revealed to be related to the lobe-specific carcinogenic effects of cadmium in the rat prostate. The experiment showed that the MT gene has higher expression under normal circumstances in the dorsolateral lobe of the prostate, while expression in the ventral lobe is much lower. The basal expression in the testes of MT was relatively lower than in the dorsolateral prostate but is substantially higher than in the liver.

An analysis of the quantitative structure-activity relationships (QSAR) between acute toxicity of 88 general pollutants revealed that the correct classification rate reaches 95% in a training set and a prediction rate of about 90%. Using an expert system approach, the QSAR for general pollutants in organic industrial waste to Daphnia magna and eight molecular descriptors are analyzed.

Tyrosine hydroxylase (TH) activity substantially increased at Pb concentrations ranging from 0.5 nM to 5 microM on three enzymes involved in catecholamine biosynthesis. The study, using pheochromocytoma cells (PC12), aimed to determine the effects of lead (Pb) on the activity of three enzymes namely aromatic L-amino acid decarboxylase (AAAD), tyrosine hydroxylase (TH) and dopamine beta-hydroxylase. The study also showed a differential effect on TH mRNA levels in confluent versus nonconfluent PC12 cells.

Lead levels in saliva and blood in acute administration of lead in rats exhibit a linear correlation. The study, which aims to determine the effects of lead acetate (100 mg/kg) after repeated intraperitoneal injection in parotid and submandibular saliva and blood in rats, also showed that pure saliva can be utilized to indicate lead exposure. Lead concentrations were determined by flame atomic absorption spectroscopy.

Laser cytometric methods were used to evaluate the effects of the pyrethroid insecticide permethrin on the epithelial cell lines of two insect species and on the clonal rat liver cell, to evaluate its other cellular injury effects. Inhibition of cell proliferation was achieved in the two insect epithelial cells at 15nM and 300nM concentrations, while the clonal rat liver cells were shown to be affected in their GSH, GJIC, MMP and ROS generation activities.

The physiological toxicity of nickel pollutants was evaluated. Intratracheal administration of nickel chloride in three rat test groups found nickel concentrating in the lung, heart and liver. Several of the effects of nickel were found to be in altering the lactate dehydrogenase and alanine transaminase activity. Much of the damage caused by the nickel in the heart and liver, where decreased activity of the abovementioned enzymes was observed.

A survey was conducted on the mental and neurological effects of low lead levels in 395 children in the industrial city of Bratislava, Republic of Slovakia. Results showed a nonsignificant positive correlation between low lead levels in the blood and the child's mental and neurological health. The results however are still inconclusive due to the number of confounders in the study that were not filtered out by the multivariate statistical treatment of the data.

Cimetidine has been shown to have a significant effect on the pharmokinetics of paracetamol. Studies show that cimetidine slows down the absorption of paracetamol, the lag time being increased by more than 200% and was shown to be independent of pH. The action of cimetidine is believed to be direct on the gut smooth muscle and indirect on gastric emptying. This finding is supported by tests on guinea pigs wherein high concentrations of cimetidine induced the relaxation of the ileum.

Study results suggest that glycerol formal, one of the constituent solvents found in Merck's Ivomec, is responsible for the drug's dysmorphogenic effects on mouse embryos. Glycerol formal, administered at 21 or fewer micrograms/mililiter, resulted in dose-dependent malformations. The mechanisms responsible for the substance's negative effects are not yet clear.

A study on the acute toxicity and primary irritancy of 43 amines produced variable results but revealed some general trends. The higher and lower aliphatic amines, applied perorally and percutaneously, produced moderately to highly toxic effects. Dosing with aromatic amines and cycloamines also had a moderately to highly toxic impact. Among the materials tested, sulfatoamines and amine salts were the least toxic.

Study results indicate that Cardioxane (ICRF-187, dexrazoxane) is an ineffective protection against peroxidative heart damage in rats. The results show that Cardioxane administered in clinically meaningful doses does not significantly impact serum enzyme level changes observed after either of two cardiotoxic agents and has no protective impact against oxidative reactions.

A toxicokinetic study of the behavior of parathion, a widely-used organophosphorus pesticide, and its primary metabolite, paraoxon, demonstrated that the two substances accumulate in rat tissues. Study results show that the main difference in the toxicokinetic behavior of parathion and paraoxon is seen in muscles, while the former behaves similarly in blood and adipose tissue. The study also showed that the two compounds accumulate principally in the liver.

Study results indicate that exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental contaminant, can cause changes in hematopoietic cell populations in the bone marrow, spleen and thymus of geriatric mice. Exposure to 10.0 microgram/kilogram of TCDD, when unchanged percentages of cells expressing Mac-1, CD45 and CD45R antigens were present, resulted in a significant, though limited, decline in bone marrow cellularity.

Study results fail to clearly demonstrate chelation therapy's effectiveness and safety in removing lead from cattle. An experiment using five lactating Holstein cows that were administered meso-2,3-dimercaptosuccinic acid and monoisoamyl meso-2,3-dimercaptosuccinate demonstrated that 0.3 mg/kg doses of those chelators were inadequate to cause large amounts of lead excretion through urine.