PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Thymus Extracts”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 343 records · Page 19Linked to original sources

Thymic hormone modulation of leukemogenic virus replication.

The effect of purified calf thymus extract, thymosin, on infection with murine leukemia virus (MuLV) (Rauscher) was studied in adult thymectomized BALB/c mice. The course of infection was determined by virus titer in the blood plasma, by enumeration of spleen cells replicating MuLV (i.e., infectious centers), and by the examination of cells for expression of virus-induced cell membrane antigen. Thymectomy (performed 1 week prior to the virus injection) decreased MuLV infection by all three parameters. However, administration of thymosin (500 mug, given in equal doses 2 days before and at the time of injection of virus) caused a marked increase of plasma titer of virus, as well as an increased number of spleen cells generating MuLV as compared to controls treated either with purified spleen fraction or with diluent (buffered salt solution). More than two doses of thymic extract (up to nine, given every 2 days after infection) had no further effect on plasma virus titer or number of splenic infectious centers. Furthermore, treatment of mice with either thymic or splenic extracts increased the incidence of virus related membrane antigen appearing on the surface of spleen cells, as compared to diluent-treated control animals. These results indicate that thymosin may enhance infection by or replication of murine oncornaviruses.

Animals↗

Partial response of metastatic hepatocellular carcinoma after treatment with thymostimulin.

We describe a case of partial regression of metastatic hepatocellular carcinoma after treatment with thymostimulin. The patient, a 58-year-old man, received no specific therapy for his tumor, but only a thymus extract ("thymostimulin"). At follow-up 6 months later the patient showed clinical improvement, reduction of alpha-fetoprotein level an liver lesions, and a complete regression of lung metastases. The patient died of progression of the disease with 2-year overall survival.

Adjuvants, Immunologic↗

Antihypertensive effect of an immunosuppressive agent, cyclophosphamide, in genetically hypertensive rats of the Lyon strain.

The effect of a pharmacological immunosuppression on the development of hypertension and the part played by hormonal secretions of the thymus in this disease were investigated in genetically hypertensive rats (LH) of the Lyon strain. For this purpose, systolic blood pressure (SBP) was measured in cyclophosphamide-treated LH rats and in neonatally thymectomized LH rats receiving thymostimulin, a thymus extract. Cyclophosphamide treatment delayed the onset and attenuated the full development of hypertension in LH rats whereas it had no effect on SBP in normotensive rats (LN). Thymectomized LH rats also exhibited a significantly decreased SBP as compared to sham-operated controls. Thymostimulin treatment slightly increased the SBP of thymectomized LH rats but did not restore it to the level seen in sham-operated animals. These results showed that thymic hormonal secretions did not seem to be involved in the initiation of hypertension. By contrast, the fact that a reduction of hypertension could be obtained either by thymectomy or cyclophosphamide treatment suggested that immune disorders, mediated by thymus-dependent cellular reactions, could be of pathogenic importance in the development of hypertension in LH rats.

Aging↗

Immunobiological and pharmacological properties of thymus factor X (TFX). II. Immunotropic activity.

Immunobiological effect of the active thymus extract (preparation TFX) was evaluated in vitro. It was shown that the preparation exerts a protective effect, in relation to the cytotoxic action of hydrocortisone, and restores lymphocyte sensitivity to imuran in thymectomized mice. The findings show that preparation TFX has an activity corresponding to that of Goldstein's thymosin. The unit of immunotropic activity of TFX was introduced. Besides, cell-mediated reactions (skin test, MIF) displayed immunogenic properties of TFX.

Animals↗

Immunological activity of fractions of thymus factor X (TFX).

Immunotropic activity of 5 fractions of thymus extract (TFX) was evaluated in vitro. It was shown that, except fraction IV, they exerted protective effect in relation to the cytotoxicity activity of hydrocortisone. Beside, all but fraction IV restored the ability of lymphocytes for rosette formation, suppressed previously by the introduction of imuran. In both experimental systems fraction V exhibited the strongest effect. The division of fraction V into subfractions--A and B showed that practically all thymosin activity is concentrated in subfraction B.

Animals↗

Increase of OKT4+ cells during treatment with thymostimulin in parenteral drug addicts with persistent generalized lymphadenopathy.

Thymostimulin (TP-1), a parenterally administered calf thymus extract, has induced a significant increase of OKT4+ peripheral cells in 9 drug addicts with persistent generalized lymphadenopathy; OKT4+ lymphocytes decreased gradually after withdrawal of treatment. In a control group, a spontaneous decrease occurred in the same period of observation. A more prolonged treatment should be undertaken to assess the effectiveness of the drug on the evolution of the disease.

Adult↗

Stabilization of double-stranded DNA molecule by non-histone peptidic effector from calf thymus.

A peptidic effector from calf thymus causes a strong stabilization of DNA double-stranded molecule in vitro. The active factor was isolated from aqueous ultrafiltered thymus extracts and purified by means of chromatography on DEAE-cellulose and then on Dowex 50 WX2. The purified thymic factor was characterized as a peptide of low molecular weight (less than 5000). The biological activity of the thymic factor cannot be attributed to a histone fragment. Melting data of the control DNA and of the DNA-active factor complex in various conditions of ionic strength and dielectric constant of the solution medium are recorded.

Animals↗

[Comparison of the results of the treatment of patients with SSPE using various immunomodulating preparations].

The authors analysed the results of controlled treatment by three methods of patients in the 1st or 2nd phase of SSPE in a randomized group. The groups received: I. Propionibacterium granulosum KP-45 (interferon inducer) + isoprinosine, II--TFX (thymus extract) + isoprinosine, III--only isoprinosine. In all groups the treatment was continued during 6 months. The analysis of the clinical results of these methods failed to demonstrate a statistically significant superiority of any of these methods (among others, due to small number of cases) but an evident statistical tendency was revealed suggesting a better effectiveness of combined treatment (immunostimulator + isoprinosine) in relation to treatment with isoprinosine only. The final evaluation of the results requires further observations of these patients.

Adjuvants, Immunologic↗

[Changes of cognitive and emotional processes during immunostimulatory treatment in subacute sclerosing panencephalitis].

In 35 cases of SSPE sensibilized neuropsychological testing was done before and after 6 months of immunostimulatory and virostatic treatment. Three groups of patients were studied. All groups received isoprinosine, one group was given additionally TFX-thymus extract Polfa, and another group received additionally Propionibacterium granulosum KP-45. A tendency for improvement of verbal function and emotional status was observed only in the group receiving isoprinosine with propionibacterium. In both remaining groups, receiving only isoprinosine or isoprinosine with TFX worsening was noted, particularly in the isoprinosine-only group. This was particularly evident in the visuospatial orientation. Prolongation of survival time in SSPE owing to specific treatment increases the need for psychoreactive and therapeutic influences for stimulation of cognitive processes.

Adolescent↗

Impaired T-cell functions in aged guinea-pigs restored by thymostimulin (TS).

The age-related changes of different T-cell activities in guinea pigs and the effect of Thymostimulin (TS), a thymus extract, on the immunocompetence of these cells was studied. Mitogen-induced proliferation of peripheral blood lymphocytes was increased by TS in vitro. The intraperitoneal administration of TS (5 mg/kg) to aged animals restored the helper function of T lymphocytes and enhanced the reactivity to mitogens of both peripheral blood lymphocytes and spleen lymphocytes. The data obtained suggest that as in other species, there is an age-associated decline of immunological response, in guinea pigs too, probably due to a deficiency of thymic hormone(s) and that TS could correct this deficiency.

Aging↗

Immunobiological and pharmacological properties of thymus factor X (TFX). I. Biological and pharmacological activity.

Detailed investigations on pharmacological properties of biologically active thymus extract were performed. Its acute and chronic toxicity was determined. Influence on the circulatory and the respiratory systems as well as on the parenchymatous and the smooth muscle organs, development of fetuses and reproductive functions were evaluated. Preparation TFX proved to be well tolerated and its acute action was manifested only at high doses injected intravenously. Its effect on the smooth muscle organs and its teratogenic activity were determined in the long-term experiments. It was assumed that it can be introduced in clinical use excluding women in the reproductive period.

Abnormalities, Drug-Induced↗

[Recurrent herpes labialis infections: cellular immunity and immunomodulation].

The therapy with thymus extracts, oral and parenteral, reduced the frequency and the intensity of recurrences of herpes labialis infections. The duration of the effect was at least 6 month after interruption of the therapy. Indomethacin was effective and developed and intensive effect only during the therapy. The skin test with recall-antigens and the neopterin-elimination were altered at the first day of the menstruation during the recurrence. The normalisation succeeded during therapy. In patients with recurrences in the perimenstrual time we observed a reduced T-helper/T-suppressor index during the first day of menstruation. Normal data were registered out of the recurrence time and/or under therapy. Inhibitors of the lymphokine: leucocyte/migration inhibitory factor (LIF) with a molecular weight of 6-12 KD were obtained with the specific stimulation of mononuclear cells of patients with recurrent infections with herpes labialis using the herpes-virus-1 antigen. The inhibition of fibrinolysis/proteolysis with aprotinin, tranexamic acid, phenyl-methyl-sulphonyl-fluoride and di-isopropyl-fluorophosphate could prevent the appearance of inhibitors. Inhibitors could be produced by splitting the LIF-molecule with urokinase and plasminogen but not with trypsin. The production, but not the activity, of present LIF-inhibitors are blocked in vivo and in vitro by indomethacin and thymus peptides.

Adjuvants, Immunologic↗

Effect of treatment with thymustimulin (Tp-1) on T and B cells in lymphoproliferative disorders.

The effect of the calf thymus extract thymustimulin (Tp-1) on lymphocyte subpopulations of 12 patients affected by lymphoproliferative disorders with low T-cell level was studied. T and B cells of four patients with non-Hodgkin lymphoma, three with Hodgkin's disease, one with myeloma and four with chronic lymphatic leukemia were evaluated before and after treatment for 3 months with Tp-1. The total number and the percentage of T-cells increased significantly (p less than 0.05) in patients with non Hodgkin lymphoma, Hodgkin's disease and myeloma and only numerically in patients with chronic lymphatic leukemia, while no significant change of the total WBC count and of the total number and percentage of B-cells occurred in any patients. These results suggest that Tp-1 treatment might be effective in restoring immunocompetence in patients with T-cell deficiency secondary to lymphoproliferative disorders.

Adult↗

A placebo-controlled trial of thymic hormone treatment of recurrent herpes simplex labialis infection in immunodeficient hosts.

Twenty-one immunodeficient patients with recurrent herpes simplex labialis (HSL) were randomly allocated to either saline or the bovine thymus extract thymostimulin (TS) and treated for a period of 6 months. An impressive reduction in both number and severity of the recurrences of the infection was observed in TS-treated patients during the trial and for up to 3 months afterward. A significant increase in total WBC, lymphocyte count, and T cells was detected in the TS group after 6 months. In vitro lymphoproliferative responses to herpes simplex virus antigen and natural killer cell activity were also significantly higher in the TS group, whereas no significant difference in antibody titers to herpes simplex could be detected between the two groups. TS can therefore help prevent viral reactivation in immunocompromised hosts by potentiating cell-mediated immune responses and should be considered for use in prophylaxis of infection in patients at risk and also in apparently normal subjects with recurrent HSL.

Adolescent↗

A double-blind placebo-controlled study of thymostimulin (TP-1) for the treatment of atopic eczema.

Twenty-nine patients with severe atopic eczema were entered into a randomized double-blind, placebo-controlled trial of the polypeptide thymus extract, thymostimulin (TP-1). The treatment period was 10 weeks with a subsequent follow-up period of up to 1 year. Of the 18 patients receiving TP-1 and the 11 patients on the placebo, 15 and 11 patients, respectively, were fully evaluable. There was no significant difference in either clinical or immunological status between the two treatment groups at baseline. At the 3-month follow-up clinic visit there was a statistically significant difference in the total clinical score, calculated as a percentage of baseline, in favour of the TP-1-treated patients. This difference was not maintained in the subsequent follow-up period and was not accompanied by an improvement in the patient's subjective well-being. There was no significant difference between the treatment groups with respect to the immunological parameters as measured at the 3-month clinic visit.

Adjuvants, Immunologic↗

A thymic factor increasing the blood sugar level.

The thymus extract prepared by using isotonic NaC1 solution causes hyperglycaemy and the thymectomy, too, produces the same effect. Consequently, the active substance of the thymus is produced elsewhere in the organism and being stored within the thymus, gets into the extract by homogenizing its cells. Both the thymectomy and the thymic factor increase the effect of alloxan and this sensitizing effect can be prevented by pretreatment with prednisolone.

Alloxan↗

The in vivo effect of thymic factor (thymostimulin) administration on circulating immune complexes and serum lysozyme levels in untreated Hodgkin's disease patients.

The in vivo effect of a calf thymus extract, thymostimulin, on the levels of circulating immune complexes (CIC) and serum lysozyme was evaluated in 32 patients with untreated Hodgkin's disease. Using the platelet aggregation test for detecting CICs, 12 patients (37%) had positive titers before thymostimulin treatment; 3 patients (10%) remained positive following therapy. Serum levels of Clq-binding immune complexes were evaluated (greater than 24.5 micrograms/ml) in 8 patients prior to thymostimulin therapy (mean value: 42.3 micrograms/ml); 3 patients continued to have elevated levels after treatment. Serum lysozyme levels for Hodgkin's patients was similar to control values (10.6 vs. 8.3 micrograms/ml); however, the Hodgkin's patients with initially elevated CICs had a lower serum lysozyme level than patients with initially normal CICs (12.9 vs. 7.3, p less than 0.02). Thymostimulin increased serum lysozyme levels in the Hodgkin's patients in whom the CICs were initially elevated (7.3 vs. 10.4 micrograms/ml, p less than 0.05). These data suggest that thymostimulin exerts an effect on the nonspecific immune system of Hodgkin's disease patients.

Animals↗

A placebo-controlled trial of thymic hormone treatment of recurrent herpes simplex labialis infection in immunodeficient host: results after a 1-year follow-up.

Twenty-one immunodeficient patients with recurrent herpes simplex labialis (HSL) were randomly allocated to either the saline or the bovine thymus extract Thymostimulin (TS) group and treated for a period of 6 months. A total of 17 recurrences with a mean severity index of 266.2 +/- 192 in the TS-treated group versus a total of 62 recurrences in the placebo group (score 458.8 +/- 299.6) were observed after 12 months of follow-up. A significant increase of total WBC (P less than 0.05 versus control group), lymphocyte count, and T-cell number (P less than 0.001) were detected in the TS group after 6 months as well as after 12 months. In vitro lymphoproliferative responses to herpes simplex virus antigen and natural killer cell activity were also significantly higher (P less than 0.05) in the TS group, whereas no significant difference in antibody titers to herpes simplex could be detected between the two groups. TS may be potentially useful in preventing viral reactivation in immunocompromised hosts by potentiating cell-mediated immune responses. Further studies evaluating TS for prophylaxis of infection in patients at risk should be considered.

Adolescent↗