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D Yonkosky

Publications and source records attributed to D Yonkosky.

8 recordsLinked to original sources

Scabies in nursing homes: an eradication program with permethrin 5% cream.

Permethrin 5% cream was used to treat scabies in three large nursing homes under a compassionate-plea protocol for chronic, therapy-resistant infestations. All residents, staff, and frequent visitors were treated whether or not symptomatic. Family members of these groups were treated either when symptomatic or directly exposed to scabies. Nine hundred ninety-five persons were treated, 202 of whom were diagnosed with scabies. Approximately 35% (111 of 313) of nursing home residents were diagnosed with scabies. These were patients in whom multiple treatments with other scabicides were unsuccessful. At the completion of the study, 195 patients were examined for efficacy of treatment. Of these, 91 (46.7%) had clearing of lesions with one medication application, 77 (39.5%) with two treatments, and 23 (11.8%) with three or more treatments. The overall cure rate was 98%. Adverse experiences occurred in 2.4% of cases and were mild (i.e., pruritus and rash).

Adolescent↗

Casein-induced experimental amyloidosis. IX. Alterations in marrow dependent function.

CBA/J mice receiving multiple injections of sodium caseinate (CAS) or bovine serum albumin (BSA) were assayed for marrow dependent functions by measuring their ability (i) to reject bone marrow allografts and (ii) to resist Friend virus (FV)-induced suppression of lymphocyte mitogenesis. Mice that developed amyloidosis following 25-30 injections completely lost the ability to reject allogeneic marrow cells, whereas nonamyloid BSA-treated mice had enhanced rejection of marrow allografts. There was increased resistance to the suppressive effects of FV in spleen cells from 'preamyloid' mice receiving CAS injections and nonamyloid mice receiving 10-40 BSA injections. Amyloid mice appeared to be as susceptible to the effects of FV-induced suppression as control (untreated) animals. These data indicate that alterations in marrow dependent function may be related to the pathogenesis of amyloid disease.

Amyloidosis↗

Enrichment of the murine natural killer (NK) and mitogen induced cellular cytotoxicity (MICC) cells using preparative free-flow high voltage electrophoresis.

A procedure using preparative free-flow high voltage electrophoresis is described for the fractionation of murine spleen and bone marrow cells so as to obtain cell subpopulations that are either enriched in or depleted of "natural killer" (NK) cells and "mitogen-induced cellular cytotoxicity" (MICC) effector cells. A nearly three fold enrichment in the NK and MICC activities of spleen cells was achieved. The enrichment in these cells could be further increased if the phagocytic cells were removed prior to electrophoresis. When bone marrow cells were fractionated a two and a half fold increase of NK activity, and a one and a half fold enrichment of MICC activity was achieved. In both cases, other fractions were nearly devoid of NK and MICC activity. The cell recovery after electrophoresis averages 70% of the cells applied, and at least 90% of these cells were viable. MICC and NK effector cells could not be separated to a useful extent electrophoretically but were found to be separable using Sephadex C-10 gel filtration columns. The MICC but not the NK cells were retained on these columns.

Animals↗

Suppression of antibody responses in allogeneic mice by products of lymphoid tissue. I. Allogeneic suppressive factor (ASF) from spleens repopulated with thymus cells.

A cellfree extract prepared from the spleen cells of C3H mice is capable of suppressing antibody responses to SRBC when extract material is exposed to alloantigens. The observed immunosuppression was attributed to a soluble factor in the extract. This allogeneic suppressive factor (ASF) was detected in extracts prepared from the spleen cells of unirradiated mice as well as those of irradiated mice repopulated with thymocytes, provided that mice were previously immunized with SRBC. Donors of actively suppressive ASF preparations did not need to be previously exposed to alloantigens. Extracts from thymus and marrow cells of unirradiated mice and the spleen cells of irradiated mice repopulated with marrow cells (or no cells) did not contain ASF. C3H thymocytes stimulated with SRBC generated more ASF activity in spleens of C3BF1 hosts than in those of C3H hosts, indicating that alloantigenic stimulation enhances the production or activity of ASF. Once produced, C3H ASF was able to suppress antibody responses in cell transfer experiments only if exposed to C3BF alloantigens of either donor lymphoid cells or irradiated hosts. Once exposed to alloantigens, ASF appears to be capable of suppressing antibody responses of syngeneic C3H or semi-allogeneic C3BF cells. When both donor lymphoid cells and hosts were syngeneic with the donor of the ASF, there was enhancement of antibody formation in cell transfer experiments. C3H ASF did not interfere with education of C3BF thymocytes to SRBC or with the generation of precursors of anti-SRBC antibody-forming cells by C3BF1 marrow cells. ASF may interfere with cellular cooperative events necessary for humoral immune responses or with terminal differentiation of B cells. Production of ASF could partially account for the suppression of antibody responses observed during graft-vs-host reactions.

Animals↗

Suppression of antibody responses in allogeneic mice by products of lymphoid tissue. II. Lack of antigenic specificity and immunogenetic requirements of allogeneic suppressive factor (ASF).

Mice were irradiated, infused with thymocytes and immunized with a variety of antigens, i.e., sheep or horse red blood cells (SRBC or HRBC), diphtheria toxoid (DT) or bovine gamma-globulin (BGG). The spleen cells (T.Spleen cells) were harvested 5 days later and cellfree extracts were prepared. The extracts contained an allogeneic suppressive factor (ASF) that was capable of inhibiting IgM antibody responses of allogeneic or semi-allogeneic unirradiated mice. ASF had to be injected within 24 hr of immunization to be effective and a single injection delayed, rather than abolished, the antibody response at the cellular level. However, daily injections of ASF resulted in persistent suppression of antibody response. ASF activity was antigen nonspecific, i.e., the antigen used to stimulate ASF production did not have to be the same as the antigen used to test for ASF activity. C3H T.Spleen extracts were even immunosuppressive when prepared by exposure to C3BF1 alloantigens only; such extracts suppressed antibody responses of C3BF1 and DBA/2 mice. C3H ASF was removed from extracts after incubation with C3BF1 spleen cells but not after incubation with C3H spleen cells. C3BF1 spleen cells which had been preincubated with C3H ASF were unable to generate antibody-forming cells upon transfer to irradiated C3BF1 host mice. This suggests that the ASF molecule may be or include receptors for alloantigens. The immunogenetic requirements for ASF activity were evaluated by injecting extracts from C3H, C57BL, C3BF and BALB/c T.Spleen cells into C3H, CBA, C57BL, BALB/c, DBA/2, A or C3H.A recipient mice. All extracts tested had ASF activity. However, all allogeneic recipients were not suppressed by the extract material. The suppressive activity of ASF seemed to require two (or more) antigenic differences between donors and recipients of extract material, an H-2K or I antigen difference and a second antigen difference, possibility Ig-1. In the limited numbers of strain combinations tested, T.Spleen extracts suppressed IgM antibody response only if exposed to H-2 and Ig-1 antigens, e.g., BALB/c (H-2d, Ig-1a) ASF suppressed A (H-2a, Ig-1e) but not C3H.A (H-2a, Ig-1a) or DBA/2 (H-2d, Ig-1c). Separate ASF molecules may react with separate antigens on the cell surface, i.e., with H-2 and gammaG2a. Alternatively, one ASF molecule may react with two structurally associated antigens. If the latter is correct, it is conceivable that the beta2-microglobulin which is non-covalently linked to the major component of H-2 molecules expresses allotypic antigens coded for by Ig-1 and beta2-microglobulin is one of the antigens recognized by ASF.

Animals↗