Mucinous cystadenoma in the lung of a captive-born moustached tamarin (Saguinus mystax).

A 2-year-old, captive-born, male moustached tamarin was subjected to necropsy examination after a fatal head trauma. A solitary, circumscribed, subpleural mass (0.6 cm diameter) was found in the right caudal lung lobe. The mass was diagnosed as a mucinous cystadenoma. Histochemical and immunohistochemical tests were performed to further characterize the tumour. Surfactant proteins A, B, C and D were not found in the neoplastic cells, suggesting that the tumour arose from a non-surfactant-producing alveolar lining cell. Pulmonary mucinous cystadenomas are uncommon benign tumours in man and have not been reported previously in animals.

Spontaneous pulmonary alveolar proteinosis in captive "moustached tamarins" (Saguinus mystax).

Pulmonary alveolar proteinosis is a rare human disease characterized by accumulation of surfactant in alveoli without generating an inflammatory response. Lung lesions resembling pulmonary alveolar proteinosis were observed in 7 adult tamarins (5 males and 2 females). Gross lesions were characterized by areas of discoloration, slight bulging over the lung parenchyma, and occasional consolidation. Histologic examination of tamarin lung samples revealed intra-alveolar accumulation of amorphous, amphophilic, periodic acid-Schiff-positive, finely granular to dense material. In some cases, type II pneumocyte hypertrophy and hyperplasia were observed with pleural and septal thickening and fibrosis. Large numbers of intra-alveolar foamy macrophages were noted surrounding and/or in the vicinity of the lesions. Immunohistochemical analysis of the lung lesions using polyclonal (surfactant proteins A, B, and C) and monoclonal (surfactant protein D) antibodies revealed the granular material to be composed largely of surfactant protein B, followed by surfactant protein A. Surfactant proteins C and D were present in lesser quantities, with the latter observed surrounding the lipoproteinaceous deposits. Transmission electron microscopy of the affected lungs showed numerous, irregularly shaped osmiophilic lamellar bodies in type II pneumocytes. The cytoplasm in alveolar macrophages was expanded, containing ingested surfactant with swollen mitochondria and rough endoplasmic reticulum. Thoracic radiographs, available in 1 animal, depicted the lesions as small multifocal opacities randomly distributed in cranial and diaphragmatic lung lobes. This is, to the authors' knowledge, the first report of spontaneous pulmonary alveolar proteinosis in nonhuman primates.

Chronic stavudine exposure induces hepatic mitochondrial toxicity in adult Erythrocebus patas monkeys.

OBJECTIVES: To understand the mitochondrial mechanisms underlying the lactic acidosis and hepatic steatosis seen in some HIV-1-infected individuals after long-term stavudine (d4T) exposure, we have explored mitochondrial integrity in adult monkeys (Erythrocebus patas) given a daily human equivalent dose of d4T for 78 days. STUDY DESIGN/METHODS: Three Erythrocebus patas (patas) monkeys were given 3 mg d4T orally twice daily (total 6 mg d4T), or approximately 1.2 mg d4T/kg body weight per day, for 78 days and compared with 3 unexposed animals. Blood taken from controls and from treated monkeys before and after drug exposure was subjected to a complete clinical chemistry profile. Liver and skeletal muscles were examined for oxidative phosphorylation enzyme specific activities, mitochondrial deoxyribonucleic acid (mtDNA) quantity by slot blot, and mtDNA integrity by Southern blot. RESULTS: Clinical chemistry assays demonstrated few significant differences; however, one d4T-exposed monkey had a serum lactate of 8.1 mmol/L after 78 days of oral d4T ingestion. Specific activities of oxidative phosphorylation Complexes I, II, and IV were significantly altered in both livers and skeletal muscles from the d4T-exposed animals, compared with the controls (p < or = 0.05). Significant depletion of mitochondrial DNA was observed in livers of drug-exposed monkeys, but not in skeletal muscle (p < or = 0.05). Further examination of liver DNA by Southern blot confirmed hepatic mtDNA depletion in drug exposed animals. CONCLUSIONS: The data suggest that direct examination of the liver may be required to elucidate clinical d4T-induced hepatotoxicity related to mitochondrial damage.

Genotoxic and functional consequences of transplacental zidovudine exposure in fetal monkey brain mitochondria.

Mitochondrial toxicity was assessed in the brains of developing Erythrocebus patas monkey fetuses exposed in utero to the nucleoside analogue drug zidovudine (3'-azido-3'deoxythymidine or AZT). Pregnant E. patas monkeys were given 0 (n = 5), 10 (n = 3), and 40 (n = 3) mg of AZT/day, equivalent to 21 and 86% of the human daily dose, for the last half (about 10 weeks) of gestation. Mitochondria were isolated from fetal cerebrum and cerebellum at birth and mitochondrial morphology was examined in these tissues by transmission electron microscopy (TEM). Oxidative phosphorylation (OXPHOS) enzyme specific activities were measured spectrophotometrically. Mitochondrial DNA (mtDNA) integrity and quantity were determined by Southern blot and slot blot analysis. In the cerebral mitochondria, reduced nicotinamide adenine dinucleotide (NADH) dehydrogenase (complex I) specific activity decreased by 25% in monkeys treated with 40 mg of AZT/day compared with unexposed monkeys (p > or = .05). At the same AZT dose in the cerebral mitochondria, succinate dehydrogenase (complex II) and cytochrome c reductase (complex IV)-specific activities showed dose-dependent increases (p > or = .05), compared with those in controls. In the cerebellum, no difference was seen in mitochondrial OXPHOS enzyme activities between unexposed and exposed fetuses. Furthermore, TEM demonstrated no difference in mitochondrial morphology in frontal cerebrum or cerebellum from unexposed and exposed fetuses, and all fetuses had similar amounts of mtDNA in both tissues. Cerebral mtDNA degradation was noted in the highest AZT dosage group, whereas mtDNA from cerebellum was uneffected. Thus, in fetal patas monkeys given a human equivalent daily dose of AZT during the last half of pregnancy, mitochondria in the fetal cerebrum appear to sustain moderate damage, while the fetal cerebellum mitochondria were not effected.

Fetal mitochondrial heart and skeletal muscle damage in Erythrocebus patas monkeys exposed in utero to 3'-azido-3'-deoxythymidine.

3'-azido-3'-deoxythymidine (AZT) is given to pregnant women positive for the human immunodeficiency virus type 1 (HIV-1) to reduce maternal-fetal viral transmission. To explore fetal mitochondrial consequences of this exposure, pregnant Erythrocebus patas monkeys were given daily doses of 1.5 mg (21% of the human daily dose) and 6.0 mg (86% of the human daily dose) of AZT/kg body weight (bw), for the second half of gestation. At term, electron microscopy of fetal cardiac and skeletal muscle showed abnormal and disrupted sarcomeres with myofibrillar loss. Some abnormally shaped mitochondria with disrupted cristae were observed in skeletal muscle myocytes. Oxidative phosphorylation (OXPHOS) enzyme assays showed dose-dependent alterations. At the human-equivalent dose of AZT (6 mg of AZT/kg bw), there was an approximately 85% decrease in the specific activity of NADH dehydrogenase (complex I) and three- to sixfold increases in specific activities of succinate dehydrogenase (complex II) and cytochrome-c oxidase (complex IV). Furthermore, a dose-dependent depletion of mitochondrial DNA levels was observed in both tissues. The data demonstrate that transplacental AZT exposure causes cardiac and skeletal muscle mitochondrial myopathy in the patas monkey fetus.

Lesions of experimental genital Tritrichomonas foetus infections in estrogenized BALB/c mice.

Ninety-seven BALB/c mice were inoculated intravaginally with 8.0 x 10(5) Tritrichomonas foetus organisms, using either isolate ATCC 30003 or field isolate MU Y22 2 days after estrogenization with 15 micrograms 17 beta-estradiol. Reproductive tracts were examined at several time points post-inoculation to determine gross and histologic responses to trichomonad infection as compared to estrogenized, uninfected control animals. The two isolates varied greatly in ability to maintain chronic infection; no ATCC 30003-inoculated animals remained culture-positive beyond 7 weeks post-inoculation, whereas MU Y22-inoculated animals were infected for greater than 26 weeks. Lesions were seen in 40-60% of animals prior to 10 weeks post-inoculation and included moderate uterine dilation and glandular atrophy, uterine gland abscesses, pyometra, intramural perivascular lymphoid infiltrates, and ovarian bursitis. The severity of lesions was independent of the T. foetus isolate. Lesions became more severe at 10 weeks post-inoculation, and at 10 and 26 weeks post-inoculation, lesions were seen in 60% and 75% of animals, respectively. In addition to lesions described above, epithelial changes were marked at these late necropsies, including ulceration, flattening, hypertrophy, and squamous metaplasia. The lesions seen in these mice closely resemble those described in natural bovine infection, suggesting that the estrogenized BALB/c mouse is an excellent model for study of bovine trichomoniasis.

Tritrichomonas foetus: comparison of isolate virulence in an estrogenized mouse model.

Previous studies indicated that Tritrichomonas foetus isolate ATCC 30003 was capable of maintaining only short-term genital infection in estrogenized BALB/c mice. In the present study, the ability of eight T. foetus isolates to establish and maintain infections in intravaginally inoculated estrogenized BALB/c mice was examined. All isolates were found to be equally capable of establishing genital infections but varied greatly in ability to maintain infections. One isolate maintained infection for less than 7 weeks, four isolates maintained intermediate infections lasting less than 13 weeks, and three isolates maintained chronic infections of greater than 26 weeks. Varying the number of trophozoites inoculated intravaginally decreased the ability of isolates to establish infection but did not affect maintenance of infection. Prolonged passage of T. foetus isolates either in vivo in an estrogenized nu/nu BALB/c mouse or by in vitro culture failed to affect their ability to maintain infection, suggesting that virulence was parasite-dependent and not related to environment-induced changes. Co-infection of estrogenized mice with isolates ATCC 30003 and MU Y32 failed to increase the length of ATCC 30003 infections or decrease the length of isolate MU Y32 infections. Taken together these results indicate that T. foetus isolates vary greatly in virulence in estrogenized BALB/c mice and provide evidence suggesting that maintenance of infection is a parasite-controlled factor.

Experimentally induced intravaginal Tritrichomonas foetus infection in the estrogenized mouse.

Studies were initiated to establish and maintain intravaginal Tritrichomonas foetus infections in female BALB/c mice as a model for elucidation of parasite and host factors that affect the course of vaginal protozoan infections. Results of these studies indicated that T. foetus infections could only be established in mice in which estrus was induced and maintained. Over a period of several weeks, mice induced to estrus by weekly administration of estradiol cypionate exhibited purulent vaginal discharge and perivulvar abscesses. Implantation of silastic tubing containing 15 micrograms of estradiol-17 beta proved effective in induction and maintenance of estrus and avoided the animal health problems associated with estradiol cypionate treatment. Results of quantitative experiments indicated that the duration of trichomonad infection was influenced by initial colonization of the vagina, i.e., mice with high numbers of vaginal trichomonads at 7 days after infection maintained infections longer than did mice with lower numbers of vaginal parasites. Weekly administration of either 2 or 4 mg of methylprednisolone acetate to estrogenized mice did not extend the duration of T. foetus infections, thereby suggesting that the immune response did not limit the establishment and maintenance of primary vaginal trichomonad infections. Study of estrogenized BALB/c nu/nu mice supported these observations in that establishment of T. foetus infections was difficult in nu/nu mice and that, in most nu/nu mice (76%), the course of infection was not lengthened (mean, 1.9 weeks). When examined by electron microscopy, the earliest lesions were characterized by degeneration and necrosis of chondrocytes, along with degradation of cartilage matrix. These findings confirm that quinolone arthropathy develops in juvenile rabbits and is similar to quinolone arthropathy in other laboratory animals.(ABSTRACT TRUNCATED AT 250 WORDS)