Effect of immunomodulation on experimental hymenolepiasis nana in mice

Oral infection of cortisone treated and diabetes induced groups of mice [immunosuppressed] with H. nana eggs, whether before or after infection, showed persistent hyperinfection of the gut with H. nana worms and cysticercoids, dissemination of cysticercoids to the liver and marked degenerative changes in the intestinal mucosa and liver. BCG treated groups [immunostimulated] whether before or after infection, showed no significant changes compared to the control group. Subcutaneous infection of mice resulted in severe localized cellular reaction around and infiltrating the injected H. nana eggs in BCG treated and control groups. BCG did not inhibit larval development, as cysticercoids were found in the injected sites. In cortisone treated and diabetic groups, mild cellular reaction was observed

Effect of immunomodulation on the course of experimental toxocara canis in mice

Immunosuppressed groups treated with cortisone showed fulmination of Toxocara canis infection in terms of significant increase in brain parasitism, total larval count and significant decrease in the percentage reduction of the total count. Suppression of the host inflammatory responses was detected in the liver, lungs, brain and muscles. Accelerated transit of larvae through the liver was observed when cortisone was given before infection. Whether BCG was given before or after infection, it showed no significant changes regarding all criteria compared with the control group. Induction of diabetes, whether before of after infection, led to persistence of larvae in the liver, insignificant increase in brain and total larval parasitism and insignificant decrease in the percentage reduction of the total count

Natural and induced blood dissemination of Toxoplasma gondii: experimental model in white mice and hamsters

Blood inoculation in mice showed that Toxoplasma organisms circulate in blood after 1 h of oocyst infection. Parasites were detected up to 15 days later and then disappeared from the bloodstream concomitantly with cyst formation in the brain, probably due to antibody presence. Immunosuppression caused by cortisone acetate treatment induced Toxoplasma bloodstream invasion in chronically infected mice and hamsters, causing death in some. Natural dissemination is discussed in relation with congenital toxoplasmosis. Induced immunosuppressive effect is compared with that produced by natural diseases such as Hodgkin, lymphoma, AIDS and others

Effect of immunomodulation on experimental trichinosis in mice

Three experimental designs were employed in the present study for evaluation of the immune mechanisms involved in different phases of Trichinella infection in mice, through alteration of the immune status of the host. Immunosuppression by cortisone and chemically induced diabetes led to fulmination of infection manifested as chronicity of intestinal phase and increased muscle parasitism. This suggests that diabetes greatly suppresses cell-mediated immune mechanisms in trichinosis. It also indicates the importance of cell mediated immune responses in control of Trichinella infection. BCG administration before infection led to suppression of the intestinal immune mechanisms, although it led to stimulation of intestinal and systemic defense mechanisms and increased muscle inflammatory response when given 2 and 3 weeks after infection, resulting in reduction of muscle parasitism

Efecto de los corticosteroides en la trasmisión congénita de toxoplamosis experimental / Effect of corticosteroids in the congenital transmission of experimental toxoplasmosis

Female white mice with chronic toxoplamosis were treated with cortisone acetate (3mg for each 25 g of body weight) 12, 8, 4 and 0 days before mating. Cortisone induces congenital transmission of T. gondii

Kinetic properties of gamma-glutamyltranspeptidase and leucine-amino-peptidase in developing rat intestine: effect of hormones.

Administration of cortisone and thyroxine produced adult-type increase in the activities of soluble and membrane-bound gamma-glutamyltranspeptidase (gamma-GTP) in suckling rat intestine. Membrane-bound enzyme activity remained unaltered while the soluble enzyme activity was reduced (27%) in insulin-injected pups. Kinetic analysis revealed that the observed changes in the enzyme levels were a consequence of altered Vmax with no change in apparent Km. A 2-fold increase in the Km value was observed in adult gamma-GTP activity compared to that of suckling animals. Membrane-bound and soluble gamma-GTP yielded similar values of the Ea (9.7-13.1 kcal/mole) but exhibited apparent differences in heat stability in the control and hormone-injected groups. Leucine-amino peptidase(LAP) activity was reduced to adult levels in insulin-treated suckling animals. Thyroxine- and cortisone-treatment did not affect soluble activity but significantly (P less than 0.001) augmented the membrane-bound LAP levels. This increase was due to enhanced (54-82%) Vmax with no change in Km. The observed decrease in LAP activity in response to insulin was due to reduced Vmax. There was no change in Ea (8-11.6 kcal/mole) except the value was raised to 19.1 kcal/mole in cortisone-injected pups. Both the soluble and membrane-bound LAP activities were quite resistant to heat inactivation upto 30 min at 60 degrees C except in weanling rats. Thus, the kinetic behaviour of normally developed and precociously induced gamma-GTP and LAP is essentially similar but there are apparent differences in the mode of action of insulin, cortisone and thyroxine in affecting the development of these enzymes.

Estudio comparativo de la utilidad del ungüento de vitaminas A y D contra su excipiente en el tratamiento de diversas dermatosis / Comparative study of the usefulness ointment of vitamins A and D versus its excipient different dermatosis treatment

Se practica un estudio clínico doble ciego entre el ungüento de vitaminas A y D contra su excipiente en 62 pacientes con diferentes dermatosis de caracter eczematoso. Se evaluaron diferentes parámetros subjetivo y objetivos. Aunque no se pudo lograr una completa efectividad del excipiente más vitaminas A y D sobre el grupo control, los resultados sugieren una mayor efectividad de este medicamento

Acción inmunosupresora de los corticosteroides durante la infección primaria y después del desarrollo de la inmunidad contra Toxoplasma y Virus Herpes / Immunosuppressive action of corticosteroids during primary infection and after immunity development against Toxoplasma and Herpesvirus

Se comparó la sensibilidad al acetato de cortisona de la inmunidad en desarrollo y la inmunidad adquirida. La toxoplasmosis fue estudiada en ratones y hamsters, usando una cepa virulenta y otra avirulenta. La infección primaria y la reinfección con virus herpes del tipo 2 fueron estudiadas en ratones. Al comparar ratones y hamsters con 4 grupos de animales tratados con el corticosteroide, se observó una relación de tipo linear en la respuesta. Cuanto más alta fue la dosis de cortisona, más corta fue la sobrevivencia de los animales con cada infección, independientemente de que se tratara de infección primaria o después de establecida la inmunidad. En los hamsters la inmunidad en desarrollo fue más sensible al corticosteroide que la inmunidad adquirida. Hamsters inmunes infectados con una cepa virulenta de Toxoplasma tuvieron recidivas antes que aquellos infectados con una cepa avirulenta. Se discute la sensibilidad a la cortisona de los mecanismos inmunes en hamsters, ratones y el hombre, concluyéndose que el hombre podría ser catalogado tan sensible a este inmunosupresor como lo es el hamster

Attempts to infect experimentally immunosuppressed iris monkeys (Macaca iris) with Brugia malayi.

Iris monkeys resistant to repeated infections with B. malayi were subjected to immunosuppression by treatment with cortisone. Degree of immunosuppression was measured by: (a) blood counts, (b) lymphocyte transformation to mitogens and (c) immunofluorescent antibody to microfilarial antigens. Attempts were made to infect such immunosuppressed animals with B. malayi. No microfilariae were detected in the blood of any of the Iris monkeys during the 6 months of study. There was a sharp drop in the percentages of lymphocytes, but a rise in neutrophil counts during the first week of cortisone administration. Treatment with cortisone did not alter the antibody titres. The significance of this line of approach in the understanding of filarial resistance is discussed.