Histopathological evaluations

Koppel RA, Coleman KM, Coleman WP (2000) The efficacy of EMLA versus ELA-Max for pain relief in medium-depth chemical peeling a clinical and histopathologic evaluation. Dermatol Surg 26 61-64 Brody HJ (2001) Complications of chemical resurfacing. Dermatol Clin 3 427-437... 

Russell, L. D., Ettlin, R. A., Sinha Hikim, A. P., and Clegg, E. D. (1990). Histological and Histopathological Evaluation of the Testis. Cache River Press, Clearwater, FL. 

Liver toxicity, as evidenced by alterations in the incorporation of lysine into liver proteins, was observed in rats administered 192 mg lead/kg/day by gavage as lead acetate for 9 weeks (Barratt et al. 1989). No effects were observed at 21 mg lead/kg/day. However, the toxicological significance of this finding is not known because neither serum enzymes nor histopathological evaluations were performed. 

There has been no comprehensive evaluation of neurological function in animals after oral exposure to hexachloroethane. The data are limited primarily to clinical signs immediately after exposure and to histopathological evaluations of the brain tissues, which showed no effects. The highest NOAEL values and all LOAEL values from each reliable study for neurological effects in each species and duration category are recorded in Table 2-2 and Figure 2-2. 

Careful organ weight and histopathological evaluation of testes in general toxicity studies will detect most testicular toxins. 

Numerous physiological and environmental factors such as age, stress, nutritional deficiency, and infections may affect the immune system (Sullivan, 1989). Thus, adverse findings in animal studies may reflect these indirect immunotoxic effects rather than the direct immunotoxic potential of a chemical or drug. Indirect immunotoxic effects may be assessed through histopathologic evaluations of endocrine organs such as the adrenals and pituitary. 

The traditional approach for assessing hepatotoxicity integrates clinical chemistry markers, histopathology evaluation, cytochrome P450 enzyme induction, in-life... 

Russel LD, Ettiin R, Sinha Hikim AP, Clegg ED (1990) Histological and histopathological evaluation of the testis. Clearwater, Florida, Cache River Press. 

Dayal et al. (1989) treated BALB/c mice intraperitoneally with a single dose of 9 mmol/kg bw 2-nitropropane. In male mice, plasma activities of the hepatic enzymes sorbitol dehydrogenase, alanine aminotransferase and aspartate aminotransferase were significantly elevated, while doses of 6.7 mmol/kg bw were ineffective. In female mice, a dose of 6.7 mmol/kg bw was sufficient to cause hepatotoxicity. Histopathological evaluation revealed hepatic damage, particularly in the periportal region. 

Immunological Effects. Histopathologic evaluations in animals suggest that chlorobenzene may be immunotoxic however, direct tests of immune function have not been performed. In the absence of functional assessment, the potential for chlorobenzene to affect the immune system in humans can not be determined. 

Inflammatory changes consisting of hyperemia and bronchitis were observed in the respiratory system of rabbits exposed to 4-6 mg/m (0.30-0.45 ppm) tributyltin chloride for 95 days (Gohlke et al. 1969). Histopathology, consisting of severe bronchitis and vascular and alveolar edema, was seen in rats exposed to 2 mg tin/m (0.41 ppm) as a mixture of tributyltin dibromide (0.39 ppm), dibutyltin bromide (0.02 ppm) and hydrocarbon impurities for 80 days (Iwamoto 1960). Since these were terminal histopathological evaluations only, it is not known whether the changes were reversible or would have produced functional impairment in the animals if exposure had continued. 

Rats were exposed to a nominal concentration of 2 mg tin/m (0.41 ppm) as a mixture of tributyltin bromide (81.2%) with other compounds such as dibutyltin dibromide in acute- and intermediate-duration exposures to assess reproductive effects (Iwamoto 1960). This tin exposure was equivalent to 0.39 ppm tributyltin bromide and 0.02 ppm dibutyltin bromide. Pregnancy rates were markedly reduced after 4 weeks to 3 months of exposure however, at least partial reversibility of the effects was seen when exposure was discontinued. Histopathological evaluations were made... 

The high mortality rates in pregnant rats may indicate a parturition-related sensitivity to the toxic effects of white phosphorus. Upon histopathological evaluation of selected tissues (heart, liver, kidneys, uterus, ovaries, and testes/epididymides), the only finding considered treatment related was an increased incidence of centrilobular liver necrosis in 8/30 treated females (Bio/dynamics 1991). 

At three-months, the stenosis was reduced by 20 and 34% in the treatment groups. Histopathology evaluation showed that there were no adverse effects of the drug-loaded stent compared to the controls, and no deleterious phenomenon could be attributed to the drug tested. The intensity of fibrosis, hemorrhages, and inflammatory cell infiltration was not significantly different from the control group at three months,... 

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