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N H Altman

Publications and source records attributed to N H Altman.

At least 37 records · Page 2Linked to original sources
PubMed1991

Salivary gland oncocytes in African hedgehogs (Atelerix albiventris) mimicking cytomegalic inclusion disease.

The salivary glands from three African hedgehogs contained multiple foci of cytomegalic cells, which occasionally had a mild to moderate infiltrate of lymphocytes at the periphery. The cytomegalic cells were 35 to 40 microns in diameter with abundant acidophilic granular to hyalin cytoplasm. The nuclei were enlarged with clumped marginalized chromatin and a large, (6 to 8 microns in diameter) central, brightly eosinophilic nucleolus that had the appearance of an inclusion body by light microscopy. Histochemically most of the cytomegalic cells contained cytoplasmic metachromatic granules with Feyrter's thionine inclusion stain. Scattered cells at the periphery of the cytomegalic foci contained periodic acid-Schiff-positive cytoplasmic granules. Ultrastructurally the cytomegalic cells contained numerous tightly-packed, often bizarre, enlarged mitochondria that completely filled the cytoplasm. The nucleus consisted of a dense central core of chromatin associated with the nucleolus and the remaining chromatin was clumped and marginalized. Nuclear and cytoplasmic virions consistent with cytomegalovirus were not present. Histochemical stains of the nucleus for heavy metals were negative. The ultrastructural and histochemical findings of the cytomegalic cells were consistent with oncocytes. Previous reports in the literature of similar cells in the salivary glands of insectivores appear to have been erroneously described as cytomegalovirus infections.

Animals↗
PubMed1991

Identification of immunoglobulin light chains in canine extramedullary plasmacytomas by thioflavine T and immunohistochemistry.

Extramedullary plasmacytomas were studied in 29 dogs. The site at which tumors occurred and the age and sex of the dogs were similar to those in previous reports. The skin of the digits, chin, ear, and lip represented the most common (17/29) tumor sites. Males and females were equally represented, and tumors occurred in middle-aged to old dogs (mean age, 9.0 years). A breed predilection was seen in the Cocker Spaniel (n = 7; 24%); Cocker Spaniels represented only 4% (210/4,725) of the submissions during the same period. Tumors were stained with immunohistochemical markers (lambda light chain, K light chain) and thioflavine T. Immunoreactivity was limited to either lambda or K light chains, consistent with a monoclonal plasma cell population. The majority of tumors expressed lambda light chains, consistent with previously reported canine plasma cell dyscrasias. Thioflavine T cytoplasmic fluorescence was seen in the majority (18/29) of plasmacytomas and with inflammatory plasma cells present in control specimens. Other round cell neoplasms (lymphosarcoma, histiocytoma, and mastocytoma) were negative with thioflavine T, indicating that positive staining with thioflavine T was specific for plasma cells (neoplastic and inflammatory). This study confirms by immunohistochemistry that canine extramedullary plasmacytomas disproportionately express lambda light chains and establishes thioflavine T staining as a rapid histochemical method for diagnosis of these tumors.

Animals↗
PubMed1991

Laboratory assessment of chronic hepatitis in Syrian hamsters.

Clinical chemistry studies in the diagnosis of hamster diseases have received little attention. Although normal values exist for serum constituents, the effects of disease on these values are not well documented. Chronic hepatitis is endemic in several Syrian hamster (Mesocricetus auratus) colonies and is reported mainly through routine histologic examination. We investigated whether any differences in serum clinical chemistries were present in animals with hepatobiliary disease versus unaffected hamsters. Only serum alanine aminotransferase (ALT) and bile acids were significantly elevated in hamsters with chronic hepatitis only. In hamsters that had both chronic hepatitis and biliary disease, the serum ALT, alkaline phosphatase, cholesterol, and bile acids were significantly elevated. The results of this study indicated that serum clinical chemistries may be a useful antemortem diagnostic test for chronic hepatobiliary disease in hamsters.

Alanine Transaminase↗
PubMed1990

Dystrophic cardiac calcinosis in mice: abnormal myocardial response to freeze-thaw injury.

Dystrophic cardiac calcinosis (DCC) is a frequent finding in DBA/2, C3H and BALB/c mice and its etiology is not known. Previous studies have speculated that myocardial necrosis is involved in the pathogenesis of DCC. In this study, cardiac necrosis was induced in DBA/2, C3H and C57BL/6 mice by freeze-thaw injury through the abdominal diaphragm. Four weeks after freeze-thawing, the mice were sacrificed and the hearts and diaphragms were examined. In response to injury, cardiac mineralization was present only in DBA/2 and C3H mice. The myocardium of C57BL/6 mice (control strain) healed by fibrosis without mineralization, the normal response of the myocardium to injury. Calcified diaphragms also were present at the site of freeze-thaw injury in DBA/2 and C3H mice, which is supportive evidence that a systemic abnormality is involved in the pathogenesis of DCC. The conclusion from this study is that the pathogenesis of DCC in DBA/2 and C3H mice is multifactorial and involves both myocardial necrosis and an abnormal response to injury.

Animals↗
PubMed1989

Schisis contributes to necrosis in experimental HSV-1 retinitis.

Injection of the KOS strain of herpes simplex virus type 1 into the anterior chamber of one eye of a BALB/c mouse produces bilateral retinal inflammation which progresses in the contralateral eye to total retinal necrosis by day 10 post-inoculation. Although both immune and direct viral cytopathic effects have been proposed as causes of the initial infiltration, the precise mechanism(s) of the contralateral retinal necrosis remains uncertain. In this study, histopathological examination of the uninoculated eyes of HSV-1 injected BALB/c mice revealed the presence of vitreous traction against the internal limiting membrane of the retina which was associated with separation of the nerve fiber layer from the underlying ganglion cell layer. This separation resulted in avulsion of Mueller cell footplates and retinal vessels, hemorrhage into the schisis cavity and disruption of the underlying retinal architecture. The schisis began focally on day 8 or 9 post-inoculation, and the entire retina of most animals was involved by day 10 or 11. These results suggest that retinal schisis involving separation of the nerve fiber layer from the ganglion cell layer contributes to necrosis of the retina in the uninoculated contralateral eye.

Animals↗
PubMed1989

Neoplasia in ferrets: eleven cases with a review.

Records from a veterinary diagnostic laboratory in south Florida, U.S.A. were reviewed for cases of neoplasia in pet ferrets. Twelve ferret tumours were received over a four-year period; one case, a ferret with lymphocytic leukaemia and multi-organ involvement, had been reported previously. The other eleven tumours were: two chordomas of the tail, two sebaceous adenomas of the skin, a sebaceous epithelioma of the skin, a cutaneous mastocytoma, a malignant fibrous histiocytoma from the eyelid, a malignant mesenchymoma and an undifferentiated sarcoma from the dorsal abdominal cavity, a leiomyosarcoma found unattached in the abdominal cavity and an interstitial cell tumour of the testicle. A review of the literature yielded reports of 83 other tumours in domestic ferrets, black-footed ferrets and European polecats. Of the 95 ferret tumours, 46 were considered malignant. Tumours occurred in all organ systems except the respiratory tract and central nervous system. Affected ferrets ranged in age from 209 days to 12 years. The most frequently occurring tumours were ovarian stromal tumours (24 of 95), haemangiomas/haemangio-sarcomas (15 of 95). This information indicates that, contrary to previous opinion, ferrets appear to be subject to a similar incidence and variety of tumours as other animals.

Animals↗
PubMed1989

Feline immunodeficiency virus infection in a population of pet cats from southeastern Florida.

Blood samples from 95 randomly selected pet cats that were brought to veterinarians in southeastern Florida were tested for antibodies to feline immunodeficiency virus (FIV). Virus-specific antibodies (indicative of virus infection) were found in 8 of the 95 (8.4%) cats tested. All of the virus-infected cats were males (statistically significant, P less than or equal to 0.016) and were at least 1 year of age. The 3 most severely ill cats infected with FIV were also infected with feline leukemia virus.

Animals↗
PubMed1989

Histopathologic study of herpes virus-induced retinitis in athymic BALB/c mice: evidence for an immunopathogenic process.

In order to determine whether antiviral immunity is pathogenic in mouse eyes, HSV-1 was injected into the anterior chamber of one eye of adult athymic BALB/c mice. The eyes of these T cell deficient mice were examined clinically and histopathologically for ocular disease. The anterior segment of injected eyes developed progressive inflammatory reactions that eventually destroyed the ciliary body and then progressed to the posterior compartment where partial necrosis occurred, but only in the inner layers of the retina. A milder form of the same process developed between 7 and 10 days in the contralateral eye. Uninoculated eyes displayed little evidence of choroiditis, hemorrhage, massive necrosis, or disintegration of the architecture of the retina. Since these are features that are found in contralateral retinas of euthymic BALB/c mice infected in one eye via the anterior chamber route, it is concluded that acute retinitis found in contralateral eyes of immunocompetent mice has an immunopathogenic basis. However since euthymic mice develop anterior chamber associated immune deviation (ACAID) (and therefore do not display virus-specific delayed hypersensitivity), the identity of the relevant immune effector remains unknown. Based on these observations and our previous ocular findings following intracameral inoculation of HSV-2, we suggest that in susceptible mice, herpes simplex viruses can induce several pathogenetically distinct forms of retinitis, some of which are mediated by virus-specific immune effector cells.

Animals↗
PubMed1988

Protothecosis in two cats.

Protothecosis was diagnosed in 2 cats from Florida with nodular skin lesions. Microscopically, lesions were composed of macrophages and multinucleated giant cells arranged in solid sheets in the dermis and subcutis. In both cats, characteristic algal endospores identified as Prototheca wickerhamii were observed within the cytoplasm of infiltrating cells.

Animals↗
PubMed1988

Hepatic protection from chemical injury by isoflurane.

Isoflurane inhibits oxidative metabolism of halothane. Because hepatotoxicity of chemicals may be associated with their metabolism, whether isoflurane can protect the liver against chemical injury was investigated. Hepatic injury was produced in female F344 rats by a 30-minute exposure to 250 ppm of carbon tetrachloride. In this and all other parts of the study, the inspired oxygen concentration was maintained at 21%. The injury was accompanied by elevated activity of liver enzymes in serum (SGOT, SGPT, and SDH), enlarged liver, fatty infiltration of the liver, and vacuolar degeneration of hepatocytes. These signs of toxicity were partly or completely suppressed by concurrent exposure to subanesthetic concentrations of isoflurane (0.2 or 0.038%, respectively). The protective effect was concentration-dependent. Enflurane was protective, but less so than isoflurane. Nitrous oxide and fentanyl had no protective effect.

Alanine Transaminase↗