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Biomedical subjects

S A Houff

Publications and source records attributed to S A Houff.

At least 37 records · Page 2Linked to original sources
PubMed1983

Glial and divergent cells in primate central nervous system tumors induced by JC virus isolated from human progressive multifocal leukoencephalopathy (PML).

Immunofluorescent stains for fibronectin (FN) and glial fibrillary acidic protein (GFAP) were used in conjunction with routine histologic stains to study tumors induced in squirrel and owl monkeys by JC virus from progressive multifocal leukoencephalopathy (PML). Three varieties of glioma were identified. The first and most common variety was a neoplasm similar to grade 4 astrocytoma in humans. The second had thin, normal-appearing FN-positive vessel walls and a vastly expanded neuroectodermal parenchyma which could not be characterized by routine histologic stains. Anti-GFAP revealed the glial nature of the parenchyma. Isolating glial parenchymal cells from divergent FN-positive cells has become important to neurooncology. This type of tumor may be of particular interest for such isolations due to its high ratio of glial cells to divergent cells. The third variety was not a homogeneous neoplasm. It occurred as focal regions within tumors of the first type, and consisted of giant cells with huge nuclei. These cells resemble the cells of a human giant cell glioblastoma and bear a slight similarity to the bizarre glial cells seen in PML. The rare human giant cell glioblastoma might have an association with JC virus or with PML.

Animals↗
PubMed1983

Neuroradiological studies of JCV-induced astrocytomas in nonhuman primates.

Astrocytomas in nonhuman primates following JC virus inoculation provides a model which can be used to evaluate diagnostic and therapeutic techniques used in humans. The CT scan appearance of astrocytomas in nonhuman primates closely resembles that seen in humans. Our studies have shown that tumors may be detected in asymptomatic monkeys. Serial scans have shown astrocytomas to grow rapidly with breakdown of the blood-brain barrier. CT scanning has demonstrated the presence of tumor which was undetectable by gross examination at necropsy but confirmed by light microscopy. Studies are in progress to further define the radiological appearance of gliomas, to evaluate contrast-tagged anti-tumor antibodies as a diagnostic tool in evaluating gliomas by computerized tomography, and to evaluate metabolic parameters of actrocytomas by positron emission tomography.

Animals↗
PubMed1982

Teratological effects of western equine encephalitis virus on the fetal nervous system of Macaca mulatta.

Fetal rhesus monkeys were inoculated intracerebrally with an attenuated strain of western equine encephalitis virus. All animals developed microcephaly. Twelve of sixteen monkeys developed ex vacuo hydrocephalus. All virus inoculated fetuses developed WEE virus antibody. Virus could not be recovered at the time of delivery. Monkeys with the highest WEE antibody titers showed the greatest degree of hydrocephalus.

Animals↗
PubMed1981

Measles and canine distemper antibody. Presence in sera from patients with multiple sclerosis and matched control subjects.

Antibody to measles virus and canine distemper virus (CDV) was demonstrated in sera from patients with multiple sclerosis (MS) and from carefully matched control subjects. Elevated measles and CDV antibody titers were found in patients with MS when compared with the matched control subjects. The correlation between the measles and CDV antibody titers was quite high, suggesting that the antibody levels between the two viruses are very closely related. Based on the results of our study and a review of the literature, our conclusion is that the CDV antibody levels in patients with MS and matched control subjects are associated with occurrence of measles virus antibodies.

Antibodies, Viral↗
PubMed1981

Coronavirus antibodies in sera from patients with multiple sclerosis and matched controls.

Sera from patients with multiple sclerosis and carefully matched controls were tested for antibodies to three strains of coronavirus. There was no significant difference in the levels of antibody in the patients vs the controls. We conclude that unless the strains of coronaviruses recently reported to have been isolated from patients with multiple sclerosis express important serological differences from those used in these studies, coronaviruses are not associated with the cause of multiple sclerosis.

Animals↗
PubMed1981

Suppressor cell activity in multiple sclerosis.

Patients with multiple sclerosis and matched controls were tested for lymphocyte stimulation response and induction of suppressor cell activity in response to concanavalin A (Con A) and antigens from axolemma or myelin. Of 17 stable patients, 6 failed to have a suppressor cell response activated by one of these brain cell antigens. Among the patients who lacked these suppressor responses, five had lymphocyte stimulation responses to the same antigens. All matched controls except for one had suppressor cell responses to these antigens and none responded with a positive cellular immune reaction. We found no difference in lymphoproliferative responses to Con A in patients and controls. The level of suppressor cell activity induced by Con A in the stable MS patients varied but did not differ significantly from that of controls.

Antigens↗
PubMed1980

Experimental glioma in primates: a computed tomography model.

Owl and squirrel monkeys inoculated intracerebrally with human polyomavirus obtained from the brain of patient with progressive multifocal leukoencephalopathy developed cerebral gliomas. Among these tumors, three out of five were detected and accurately localized by contrast enhanced computed tomography (CT) when the animals were still clinically normal. Various CT features of these tumors corresponded to specific pathologic changes, such as histologic type and presence of hemorrhage and necrosis. Also, tumor progression was clearly demonstrated in repeat scans of one animal. The CT sensitivity and the capability of distinguishing various pathologic features are encouraging. It appears that a much needed, suitable model of experimental cerebral tumors in primates is now available for CT studies.

Animals↗
PubMed1980

CSF "monoclonal" bands in chronic relapsing polyneuropathy.

The characteristics and temporal profiles of cerebrospinal fluid (CSF) and serum immunoglobulin patterns on agarose gel electrophoresis were studied in 47 patients with acute idiopathic polyneuropathy (AIP) and 15 patients with chronic relapsing polyneuropathy (CRP). Nineteen of 47 patients with AIP had transient oligoclonal IgG bands, which disappeared when the neurologic signs subsided. By contrast, 14 of 15 patients with CRP had a "monoclonal" (single) IgG band, which (1) was unchanged on repeated CSF examinations over 18 months, (2) was unaffected by corticosteroid therapy, and (3) did not correlate with the severity or chronicity of the disease. Serum protein patterns and in situ central nervous system IGG synthesis and IgG:albumin index were normal in the CRP patients. The origin of the band and the nature of the putative antigen(s) that the band may be directed against were not identified. Our findings suggest that different immunopathogenic mechanisms may be operating in CRP, compared with AIP. The stable IgG band in CRP may reflect response to a persisting antigenic stimulation and, with further experience, may prove to be of prognostic significance by furnishing early in the illness: (1) a clue to the subsequent course of the disease, and (2) possible guidance on therapeutic decisions.

Chronic Disease↗
PubMed1979

Subacute sclerosing panencephalitis in only one of identical twins. A seven-year follow-up.

We report a seven-year follow-up of identical twins, in one of whom subacute sclerosing panencephalitis (SSPE) developed. Primary measles infection occurred simultaneous in both twins at age 4. The affected twin sustained a grade 1 closed head injury within six months of her primary measles infection. At age 13, SSPE was diagnosed following the onset of personality change and myoclonic seizures. Measles antibody level was elevated in the serum and CSF. After remaining in stage 2 for five years, rapid mental and neurological deterioration occurred. Measles antibody level remained elevated, and oligoclonal IgG was present in both serum and CSF. Results of neurological examination as well as virological and immunological tests were normal in the unaffected twin. Besides the occurrence of head injury, factors known to be associated with SSPE were not obviously different in the twins. We have been unable to determine a difference that would easily explain the occurrence of SSPE in only one of two identical twins.

Adolescent↗
PubMed1979

Induction of congenital hydrocephalus with mumps virus in rhesus monkeys.

Rhesus monkey fetuses were inoculated intracerebrally with wild-type mumps virus near the beginning of the last third of the gestation period. Within three days after inoculation, mumps virus was isolated from many fetal tissues. Thirteen animals receiving virus were delivered at term. Five of these showed slight to severe hydrocephalus. Hydrocephalus was most prominent in the posterior horns of the lateral ventricles, but other lesions occurred at various levels of the ventricular system. Virus was isolated from three animals at one day of age (two months after inoculation). However, mumps virus was not recovered from one-month-old monkeys. The recovery of mumps virus from newborn rhesus monkeys two months after inoculation suggests that attempts should be made to document similar persistence of the virus in humans. Furthermore, this model indicates that mumps virus infection in humans may result in hydrocephalus.

Amniotic Fluid↗
PubMed1978

Brain tumors in owl monkeys inoculated with a human polyomavirus (JC virus).

Owl monkeys were inoculated intracerebrally, subcutaneously, and intravenously with JC, BK, or SV40 virus. Two of four adult owl monkeys inoculated with JC virus, a human polyomavirus, developed brain tumors at 16 and 25 months after inoculation, respectively. A grade 3 to grade 4 astrocytoma (resembling a human glioblastoma multiforme) was found in the left cerebral hemisphere and brainstem of one monkey. The second monkey developed a malignant tumor in the left cerebral hemisphere containing both glial and neuronal cell types. Impression smears prepared from unfixed tissue of this tumor showed cells that contained polyomavirus T antigen. Virion antigens were not detected. Tumor cells cultured in vitro also contained T antigen but were negative for virion antigen. Infectious virus was not isolated from extracts of this tumor.

Antibodies, Viral↗
PubMed1978

Chlordecone intoxication in man. I. Clinical observations.

Industrial overexposure to chlordecone, an organochlorine insecticide, caused tremor in 76 of 148 exposed workers. Chlordecone was absorbed through oral, respiratory, and dermal routes, the last possibly the most significant. Epidemiology of this incident disclosed low-level, widespread environmental exposure of man to chlordecone. In 23 workers with chronic chlordecone intoxication, tremor was associated with opsoclonus, pleuritic pain and arthralgia. No seizures were reported. The site of action of chlordecone on the central nervous system is unknown. It concentrates in human adipose and hepatic tissue but is not biodegradable, either in humans or elsewhere in nature.

Chemical Phenomena↗
PubMed1978

Chlordecone intoxication in man. II. Ultrastructure of peripheral nerves and skeletal muscle.

Tremors, mental changes, opsoclonus, muscle weakness, gait ataxia, incoordination, and slurred speech developed in several employees in a Virginia chemical plant during the summer of 1974. Epidemiologic and clinical studies suggested that the chlorinated insecticide chlordecone (Kepone) was responsible. Severity of symptoms seemed directly related to dose and duration of exposure. Five sural nerve and six muscle biopsy specimens were examined by light microscopy and electronmicroscopy. The sural nerves were also evaluated by computerized morphometry, which showed considerable decrease in the number of unmyelinated fibers and lesser abnormalities of myelinated fibers. Compared with the nerves of the control subjects, those of patients may have had an increase in Reich and Elzholz bodies, and a modest increase in endoneurial collagen. There were occasional "collagen pockets," stacks of Schwann cell cytoplasmic membranes, redundant Schwann cell cytoplasmic folds, and fewer unmyelinated axons. The skeletal muscles contained increased amounts of lipofuscin and lipidlike droplets in subsarcolemmal areas and within intermyofibrillary spaces; the significance of this is unknown. Fiber size variability, type I predominance, and type grouping were present in three cases. All results strongly suggest that chlordecone is a neurotoxic agent predominantly affecting Schwann cells and unmyelinated fibers of peripheral nerves.

Adult↗