Search PubMed⌕ Search

Biomedical subjects

S H Stone

Publications and source records attributed to S H Stone.

At least 37 records · Page 2Linked to original sources
PubMed1976

Early and late contact sensitivity reactions in guinea pigs senstitzed to oxazolone.

Inbred strain 2 and random-bred guinea pigs injected oxazolone in incomplete or complete Freund's adjuvant showed contact reactions within an hour after topical application when tested 3 weeks post-sensititization. The application when tested 3 weeks post-sensitization. The time for appearance of skin reactions at 5 days post-sensitization was 8 to 24 hr, more along classic delayed-type hypersensitivity lines. Immune serum harvested several weeks after sensititazation was effective for passive transfer of early skin reactivity, while serum at 5 to 10 days was not. Lymph node cells taken 5 days after sensitization of donors could transfer only the late skin reactivity to histocompatible recipients; lymph nodes taken at 15 days did not contain cells capable of such transfers. The heterogeneity of mechanisms involved in the production of contact dermatitis suggested by these results provides new approaches to studies in this area of allergy research.

Animals↗
PubMed1975

Progressive demyelination and reparative phenomena in chronic experimental allergic encephalomyelitis.

Chronic experimental allergic encephalomyelitis (EAE), produced in inbred guinea pigs given a single inoculation during the juvenile period with isologous spinal cord in complete Freund's adjuvant, has been studied by light and electron microscopy. Most animals showed a delayed onset of nurologic signs from 12 to 68 weeks post-inoculation (PI), while several were asymptomatic up to 74 weeks PI. Two animals showed a relapsing clinical course. Examination of the spinal cords of all animals revealed chronic demyelination, remyelination, and recent demyelination. Marked perivascular inflammation, including plasma cells, was seen within demyelinated plaques. The usual type of central nervous system (CNS) remyelination was documented but in addition, remyelination of CNS axons by invading Schwann cells was noted. This Schwann cell invasion, not previously seen in EAE, was predominantly in the area of the root entry zone, and occasionally involved extensive areas of the dorsal or ventral horns. The extent of Schwann cell invasion, as well as the usual CNS-type remyelination, demonstrates the reparative capacity of the CNS. The recurrent clinical and morphologic changes in these long-term animals provides further evidence that this model of chronic EAE has many features reminiscent of multiple sclerosis. The underlying immunologic mechanisms responsible for the recurrent disease in these animals are unknown. The presence of plasma cells in the inflammatory exudates might suggest a role for B cells in these chronic animals. The possibility of an intermittent release of loculated adjuvant/antigen accounting for the recurrent disease was considered.

Animals↗
PubMed1974

The unwanted pregnancy.

A questionnaire was submitted to the mothers of 200 consecutively delivered infants; 15% of mothers were unmarried. The results showed a high prevalence of unwanted pregnancy, most accounted for by well educated, married women having their first or second baby, and despite access to contraceptive agents. Most of the married women and over 50% of the unmarried who had not wanted to become pregnant wanted the baby after its birth.

Abortion, Induced↗
PubMed1974

Cellular immune activity of a galactomannan-protein complex from mycelia of Histoplasma capsulatum.

A galactomannan-protein complex was extracted from defatted mycelium of Histoplasma capsulatum with 0.25 N alkali at 25 C. It accounted for 7.5% of the cell dry weight in nondialyzable form and had a galactose-mannose ratio of 2:5. The complex containing 68% protein was separated into polysaccharide and glycoprotein components by ion-exchange chromatography. The galactomannan formed a single precipitate in immunodiffusion, sharing a common antigen with the glycoprotein which contained two precipitating antigens. The glycoprotein elicited delayed-type hypersensitivity in guinea pigs as measured by skin-test and macrophage migration inhibitory factor assay, with 5 mug resulting in 86% specific inhibition. The galactomannan was skin-test negative, but 10 mug resulted in 80% specific inhibition of migration.

Amino Acids↗
PubMed1974

Serological and cellular immune activity of peptidoglucomannan fractions of Candida albicans cell walls.

A two-stage extraction of isolated cell walls of C. albicans resulted in 45% solubilization into antigens of high molecular weight leaving a wall residue which also had antigenic properties. Ice-cold dilute alkali removed 25% of the defatted cell walls. The extract was nondialyzable, had a glucose-to-mannose ratio of 2:3 and an amino acid content of 7.32%, and was designated peptidoglucomannan (PGM). An additional 26% of the walls resistant to stage I were solubilized by sonic treatment yielding a fraction having a glucose-to-mannose ratio of 6:1, termed soluble mannoglucan (sMG). The residue after extraction and sonic treatment contained 10.9% mannose, which was the insoluble mannoglucan. The gel permeation behavior of PGM and sMG on BioGel A5M was similar; each contained two components, one estimated to exceed 5 x 10(6) molecular weight and a second smaller species. The soluble cell wall fractions were active in immunodiffusion and carried antigenic group specificity. Immunoelectrophoresis of PGM, sMG, and mannan revealed some heterogeneity. The insoluble mannoglucan had agglutinating activity. A distinctive immunodiffusion pattern of cell wall antigens was formed with the serum of a leukemic patient with candidiasis. All three cell wall antigens and mannan elicited delayed-type hypersensitivity as measured by skin-test and specific inhibition of macrophage migration. A dose of 25 mug of PGM was sufficient to inhibit 89.9% migration in the peritoneal exudates of guinea pigs immunized with cell walls, and 10 mug of PGM inhibited 91.7% migration in guinea pigs immunized with insoluble mannoglucan.

Amino Acids↗
PubMed1968

Autoimmune chorioretinitis in rhesus monkeys.

Monkeys injected with monkey retinal tissue incorporated in Freunld's complete adjuvant developed ocular lesions characterized by choroiditic patches in the fundus periphery and sheathing of retinal vessels. Bovine retina, monkey choroid plexus, and guinea pig kidney were ineffective in this respect.

Animals↗
PubMed1968

Adoptive autoimmune encephalomyelitis in inbred guinea pigs: immunological and histological aspects.

Major variables which determine the induction and severity of adoptive autoimmune encephalomyelitis are the age and strain of the animal, and the amount of killed mycobacteria in the adjuvant. Control of these factors results in consistent production of this disease in high incidence and in severe form. The pathologic changes in the central nervous system can be correlated with the clinical disease. Maturity of the target tissues in the central nervous system of the newborn appears to be an important factor which distinguishes the response of the guinea pig from that of other species.

Animals↗
PubMed1966

Autoimmune encephalomyelitis and ocular lesions in monkeys sensitized during the neonatal period.

The neonatal rhesus monkey is susceptible to the induction of autoimmune encephalomyelitis. The disease has been produced regularly by injection of neonatal animals with guinea pig spinal cord antigen in complete Freund's adjuvant. The onset of the disease, as compared with onset in adults, is delayed and is most often heralded by intrinsic eye lesions, notably widespread retinal hemorrhages.

Animals↗