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Biomedical subjects

J L Sever

Publications and source records attributed to J L Sever.

At least 145 records · Page 8Linked to original sources

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↗

Multiple sclerosis in the Orkney and Shetland Islands. IV: Viral antibody titres and viral infections.

A controlled serologic survey of antibody titres to 17 viruses was undertaken in multiple sclerosis patients in the Orkney and Shetland Islands. No consistent pattern of elevated antibody titre levels or the presence of antibody was noted in patients compared with two control groups. Because of the isolation of these islands, the mean age at acquisition of common childhood infections, including measles, was considerably older than that of inhabitants of Europe and the United States of America. The age of occurrence of varicella was consistently younger in patients than in controls. Of note is the fact that six patients had measles after the onset of MS. This study failed to incriminate any of the viruses tested in the aetiology of MS.

Age Factors↗

Multiple sclerosis in the Orkney and Shetland Islands. V: The effect on viral titres of histocompatibility determinants.

HLA phenotypes were correlated with serum antibody titres to eight viruses in patients with multiple sclerosis and two matched control groups in the Orkney Islands. In patients, no specific HLA antigen was associated wtih increased or decreased viral titres. However, HLA-B7 was significantly correlated with higher measles titres in healthy controls. Furthermore, controls who had the HLA haplotypes, B7, DW2 ad B-cell 4, demonstrated significantly higher antibody titres to measles and rubella than controls without these determinants (P less than 0.005). To determine the effect of age, sex, and other variables upon viral titres, regression analysis was undertaken. A significant proportion of measles titre variance in patients was explained by sex and clinical factors. Among normal controls, HLA determinants explained a significant amount of measles and rubella titre variance. These data suggest that viral titres in normal individuals are influenced by certain HLA antigens and give indirect evidence that another, as yet undefined, determinant in the histocompatibility complex governs the immune response.

Antibodies, Viral↗

Experimental lead paint poisoning in nonhuman primates. II. Clinical pathologic findings and behavioral effects.

Oral administration of lead-containing paint to rhesus monkeys induced anemia, more profound in older primates. Erythrocytes were microcytic and hypochromic, but tended to become macrocytic terminally. Stippled erythrocytes were increased in all poisoned monkeys, especially in those with high blood lead levels and anemia. Proteinuria, glycosuria, casts and sloughed tubular cells containing acid-fast inclusion bodies were found on urinalysis. Terminal elevations of blood urea nitrogen were associated with profound anemia and renal tubular damage. Repeated blood lead values over 200 microgram/dl were associated with a moribund termination while monkeys which had levels under 100 microgram/dl remained apparently healthy. Behavioral studies in a small number of subclinically poisoned juveniles and neonates failed to reveal deficiencies of visual acuity or cognitive ability, nor was there evidence of alterations in levels of activity.

Anemia↗

Experimental lead paint poisoning in nonhuman primates. III. Pathologic findings.

Necropsies were performed on 25 rhesus monkeys, three cebus monkeys and three baboons which had been fed leaded paint or lead acetate at various doses up to 666 days. The 31 test primates and six controls ranged in age from five days to about eight years. In addition, the brains of 13 subadult squirrel monkeys fed lead oxide and two controls were studied grossly and microscopically. Lead content of liver, kidney and brain correlated with clinical outcome and typical histologic changes. Neuropathologic lesions, most severe in the young, occurred in 28 of 43 test primates despite a paucity of neurological signs. Brain lesions were similar to those occurring in human lead encephalopathy and included degenerative and proliferative changes of small vessels, ring hemorrhages, edema, perivascular hyalin droplets, rosette-like deposits of proteinaceous exudates, focal loss of myelin, astrogliosis and necrosis of hippocampal neurons.

Animals↗

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↗

Rubella serology: a need for improvement.

Rubella serology as performed by certain clinical laboratories is not always satisfactory. Until all the laboratory methods are improved, physicians should save all rubella sera for 1 year so that repeat testing may be conducted. The answer to the problem must come from improvements in rubella serologic tests being offered, plus improved laboratory performance and monitoring to ensure valid serologic data.

False Positive Reactions↗

CSF viral antibodies. Evaluation in amyotrophic lateral sclerosis and late-onset postpoliomyelitis progressive muscular atrophy.

Serum and CSF from 48 patients with amyotrophic lateral sclerosis and six patients with late-onset postpoliomyelitis progressive muscular atrophy were investigated for the presence of antibody to poliovirus types 1, 2, and 3, coxsackie viruses B3 and B4, influenza A, measles, rubella, mumps, herpes simplex types 1 and 2, cytomegalovirus, varicella-zoster, and Toxoplasma gondii. These results were compared with those from 53 control patients with neuromuscular disease matched for age, sex, race, and poliovirus vaccine exposure. There was no difference either in distribution of serum or CSF antibody titers or the geometric-mean antibody titers. There was no evidence suggesting the presence of locally produced specific viral antibody within the CNS to any of the agents studied. In particular, there was no serological evidence to suggest an association between persistent infection with any poliovirus type and amyotrophic lateral sclerosis or late-onset postpoliomyelitis progressive muscular atrophy.

Adult↗

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↗

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↗

HLA types and immunity in multiple sclerosis.

HLA types and levels of humoral and cell-mediated immune responses to several antigens were studied in a large group of patients with multiple sclerosis, and in controls. Patients were more likely than controls to have the DRw2 antigen. They had higher mean antibody titers to measles but not to cytomegalovirus, herpes 1, or herpes 2, and had less competent cell-mediated responses. Antibody titers to measles were lower and cell-mediated immune responses were more effective in patients with the DRw2 antigen in patients than in patients without it. This apparent specificity for measles suggests that the etiology of multiple sclerosis is related to the immune response to measles or related viruses.

Antibodies, Viral↗

Congenital rubella.

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Antibodies, Viral↗