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PubMed1989

Stage-specific expression of nucleoprotein mRNAs during rat and mouse spermiogenesis.

The expression of mRNAs for a transition protein (TP1) and two variants of protamines (P1 and P2) during rat and mouse spermiogenesis was investigated using cDNA hybridization techniques. Slot-blot analyses from 1-mm segments of seminiferous tubules and in situ hybridization from testis sections showed that the levels of mRNA for TP1 increased in step-7 round spermatids at substage VIIb of the seminiferous epithelial cycle, earlier than that of P1 and P2 at substage VIIc. The mRNA levels of all transcripts remained high during steps 8-13 in both species. In the rat, the mRNA of TP1 disappeared during step 14 between substages XIVa and XIVb. The P1 mRNA levels decreased during steps 15-16 (stages I-III) and the P2 mRNA during step 15 (stage I). In the mouse, TP1 mRNA disappeared during step 13 (stage I). The P1 mRNA level decreased before P2 in step 14 (stage II), whereas P2 was detected up to step 15 (stage V). Northern-blot analyses with all three cDNA probes revealed two sizes of mRNA and their stage-specific expression. The shorter transcripts appeared later than the longer ones, at the steps of spermiogenesis where translation is known to begin. The results suggest that transcription of TP1, P1, and P2 mRNAs starts at specifically defined times during spermiogenesis and that the temporal translational regulation of these mRNAs is different.

Animals↗
PubMed1974

Thymosin corrects the abnormal DNA synthetic response of NZB mouse thymocytes.

New Zealand Black (NZB) mice develop after 16 weeks of age an autoimmune and lymphoproliferative disease which is a model for systemic lupus erythematosus and lymphoid malignancy in humans. At this age, the mice manifest a progressive decline in T lymphocyte (thymus-derived lymphocyte) functions and serum thymosin levels. Thymocytes from 8-week old NZB mice exhibit an abnormal DNA synthetic response when transplanted into lethally irradiated C57B1/6 recipients. DNA synthesis (measured as the incorporation of radioactively labeled 5-iodo-2'-deoxyuridine) is delayed in onset and still increasing 6 days after cell transfer. By contrast, 2-week old NZB thymocytes show a normal response which is rapid in onset and completed by day 6.NZB mice were injected with thymosin fraction 5 or with bovine serum albumin starting at 2 weeks of age. Thymocytes from 8-week old thymosin-treated mice showed a normal DNA synthetic response, whereas the albumin-treated controls showed the abnormal response expected at this age. The ability of thymosin to correct the DNA synthetic response was related to dose and duration of treatment. These results suggest that thymosin can induce a more normal state of thymocyte differentiation in NZB mice. If abnormal thymocyte differentiation is related to the subsequent emergence of autoimmunity and lymphoid malignancy, then continuous treatment with thymosin may have therapeutic potential. These experiments suggest that an endocrine disturbance may contribute to autoimmune and lymphoproliferative disease in NZB mice and possibly in humans.

Age Factors↗
PubMed1991

Effects of capsaicin on rat liver S9-mediated metabolism and DNA binding of aflatoxin.

At concentrations of 25, 50, and 100 microM, capsaicin, which is the major component in various aspects of Capsicum hot peppers, decreased the binding of aflatoxin (AFB1) to calf thymus DNA by 19%, 44%, and 71%, respectively, in incubations with rat liver S9. At concentrations of 50 and 100 microM, capsaicin decreased the formation of AFB-DNA adducts (AFB1-N7-Gua) by 53% and 75% as determined by high-pressure liquid chromatography (HPLC). HPLC analysis of organo-soluble fractions showed that these effects correlated with a concentration-dependent decrease in S9-mediated metabolism of AFB1 by capsaicin. Capsaicin also altered the formation of water-soluble conjugates of AFB1. This was indicated by a decrease in radioactivity in water-soluble fractions and in glutathione conjugates of AFB1 analyzed by HPLC. These results suggest that capsaicin inhibited the biotransformation of AFB1 by modifying Phase I hepatic enzyme activity.

Aflatoxin B1↗
PubMed1993

Antimicrobial chemoimmunoprophylaxis in colorectal surgery with cefotetan and thymostimulin: prospective, controlled multicenter study. Italian Study Group on Antimicrobial Prophylaxis in Abdominal Surgery.

Surgical antimicrobial prophylaxis was performed with a controlled study on 859 evaluable patients randomized into two groups treated with chemoprophylaxis only or chemo- and immunoprophylaxis in colorectal surgery. Immuno and chemoprophylactic treatment (425 patients) consisted of 70 mg i.m. thymostimulin per day for 7 days beginning 48 h before surgery plus 2 g cefotetan at the moment of induction of anesthesia; the other group (434 patients) received only the single dose of antibiotic. Results in the two different groups were significantly different regarding abdominal abscess and the total infectious episodes in the surgical site with lower frequency in patients receiving both thymostimulin and the antibiotic (cefotetan). Moreover the respiratory tract infections were more than double in those patients not treated with perioperative immunotherapy. Stratifying patients on the basis of grade of skin test reaction, we observed a significantly lower percentage of surgical site infection in hypoergic patients receiving chemo- and immunoprophylaxis.

Adjuvants, Immunologic↗
PubMed1993

Thymomodulin stimulates phagocytosis in vitro by rat macrophages and human polymorphonuclear cells.

Activation of non-specific host defenses can increase resistance to infection in patients and especially those with reduced immune response. Thymomodulin is a calf thymic derivative containing low molecular weight peptides, which exerts immunomodulating activity probably through an enhancement of lymphocyte functions. To explore this possibility, rat macrophages (MP) and human polymorphonuclear (HPMN) cells were incubated in vitro with 100, 200, 400 micrograms/ml of thymomodulin at 37 degrees C for 60 min and their phagocytic activity was investigated. The number of phagocytosing cells was significantly increased following increasing concentrations of thymomodulin and the percentage of phagocytosis was increased more for human PMNs in comparison with rat MP, while the values of the phagocytic index were not modified after challenge with thymomodulin both for MPs and HPMNs.

Animals↗
PubMed1994

Restoration of polymorphonuclear leukocyte function in elderly subjects by thymomodulin.

Senescence is a specific physiological evolution of human beings associated with a reduction in the functionality of several apparatuses, including the immune system. Thymomodulin (TMD) contains thymus polypeptides (< 10,000 D) and it has been used in a variety of disorders associated with defective immunological functions. The aim of this study was to investigate the effect on polymorphonuclear leukocyte (PMNs) phagocytosis and oxidative burst of a 6-week treatment with 160 mg/day TMD orally in elderly subjects (85.5 +/- 9.7 years). Elderly subjects have impaired PMN phagocytosis and the following release of oxidant radicals. Treatment with TMD for 6 weeks had a restoring effect; phagocytosis and the phagocytic index were significantly improved, with increases of 132.6% and 112.5%. These findings indicate that TMD might be given to enhance the immunodefenses of immunocompromised elderly subjects. Luminol-dependent chemiluminescence was increased by 15.6%, which was not significant, indicating a different response between phagocytosis and release of oxidant radicals.

Aged↗
PubMed1967

Antigen-induced changes in lymphoid cell histones. 3. In vitro and in extract.

Previous papers in this series have reported an acute, transitory effect of antigens on lymphoid cell nuclei. In the previous reports the effect was related to a change in ammoniacal silver (A-S) stainability of smears and cryostat sections. The variable substrate was identified as histone. This paper reports the results of an extended series of studies of histone and chromatin extracts from thymus glands exposed to antigen in vivo and in vitro. The antigen effect on A-S stainability is demonstrable not only in vitro but also in chromatin fibers representing a DNA-histone complex. However, it is not demonstrable in isolated histone fractions. The inference is drawn that the antigen-induced alteration in A-S stainability is brought about not by any quantitative change in histone, but by a biologically significant shift in histone binding, perhaps to DNA. It is suggested that alteration in DNA-histone binding during gene activation may alter A-S stainability of histones.

Animals↗
PubMed1978

Microhemagglutination test for detection of antibodies to nuclear Sm and ribonucleoprotein antigens in systemic lupus erythematosus and related diseases.

A reproducible hemagglutination procedure to detect antibodies to Sm and ribonucleoprotein nuclear antigens is described. The application and interpretation is discussed. The hemagglutination test was found to be more sensitive than the immunodiffusion test; however, the hemagglutination test may not detect the presence of low titers of anti-ribonucleoprotein in the presence of a high level of anti-Sm antibody. Anti-ribonucleoprotein antibodies in the presence of high titers of anti-Sm antibodies are best identified by gel precipitation methods where precipitin lines can be characterized by their interaction with precipitin lines produced by known prototype antisera.

Animals↗
PubMed1995

Interferon and thymic hormones in the therapy of human myocarditis and idiopathic dilated cardiomyopathy.

It is becoming increasingly apparent that idiopathic dilated cardiomyopathy (IDC) probably results from an acute viral myocarditis. One reasonable hypothesis is that persistent viral infection causes myocardial destruction leading to left ventricular dilatation and heart failure. The aim of this study was to evaluate the efficacy of interferon-alpha (IFN) and thymomodulin in the treatment of idiopathic myocarditis and IDC. Clinical, immunological, haemodynamic and histological evaluation was performed in 40 patients before inclusion in the study. Patients were randomized into three treatment groups: (a) conventional therapy plus IFN, (b) conventional therapy plus thymomodulin and (c) conventional therapy alone. Two-year follow-up included repeated endomyocardial biopsy, echocardiographic evaluation, treadmill exercise test, Holter monitoring study and radionuclide assessment of left ventricular function during exercise. Left ventricular ejection fraction increased during follow-up in most of the IFN-and thymomodulin-treated patients, and only in a few of conventionally treated patients. Left ventricular reserve was significantly higher at 2-year follow-up in patients treated with immunomodulators. No serious adverse effects were noticed during treatment. Our results suggest that treatment of myocarditis and/or IDC with IFN or thymomodulin induces an earlier and significantly superior clinical improvement than conventional therapy alone.

Adolescent↗
PubMed1995

Effects of thymostimulin with combination chemotherapy in patients with aggressive non-Hodgkin's lymphoma. A report from the Italian Lymphoma Study Group (GISL).

The purpose of this study was to test the efficacy and safety of thymostimulin (TS) administered in addition to conventional chemotherapy in patients with intermediate- and high-grade non-Hodgkin's lymphoma (IG, HG-NHL). A total of 150 patients with newly diagnosed IG- or HG-NHL were entered in a multicenter trial to compare the effectiveness of two different third-generation regimens (MACOP-B versus ProMACE-CytaBOM) and were randomized to receive chemotherapy (CT) alone or CT + TS. In both regimens doxorubicin was replaced by a 20% higher dose of epidoxorubicin. TS was administered i.m. at a dose of 1 mg/kg daily on days 22-28 of each drug course to patients treated with ProMACE-CytaBOM, and on days 22-29, 50-57, and 77-85 to patients treated with MACOP-B. There were 134 fully evaluable patients: 68 treated with CT alone and 66 treated with CT + TS. Patients treated with CT + TS had a higher complete remission (CR) rate compared to patients given CT alone (59.1% vs 42.4%; P = .05). CR were significantly higher for patients treated with CT + TS in the groups with IG-NHL (P = .01), in those aged less than 60 years (P = .05), with good performance status (P = .05), and normal hemoglobin levels (P = .05). Four-year survival rates are 64.5% for patients treated with CT + TS and 43.0% for those treated with CT alone (P = .30). No difference between the two treatment arms have been observed as regards drug-related toxicity and the number and severity of infectious episodes. The use of TS during the 7 days before chemotherapy has been associated with a significantly superior CR rate. The advantage of CT + TS was mostly obtained in patients with IG-NHL, and those with good performance status or normal hemoglobin levels. In these patients TS may have potentiated the host reactions against the tumor, leading to an increase in NK activity and the production of cytokines. This postulated increase in the effectiveness of chemotherapy after TS might also explain the absence of the expected myeloprotective action.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

A double-blind, placebo-controlled trial of thymostimulin in symptomatic HIV-infected patients.

The potential therapeutic efficacy of the thymic hormone preparation, thymostimulin (TP1), in HIV infection has been studied in a multi-institutional, randomized, double-blind, placebo-controlled trial. Fifty evaluable patients with advanced AIDS-related complex (ARC) were injected with TP1 or placebo twice weekly for 6 months after 2 weeks of daily injections. The primary endpoint, progression to AIDS, was reached in nine TP1- and 11 placebo-treated subjects after 1 year. CD4 cell numbers were not affected by administration of the study drug. No toxicity was associated with TP1 treatment. We conclude that TP1 is ineffective in altering the progress of HIV disease in patients with advanced ARC.

AIDS-Related Complex↗
PubMed1979

Thymus derived inhibitor of lymphocyte proliferation. I. Isolation and assessment of tissue specificity.

Preparations from bovine thymus tissue were analyzed for their inhibitory effects during in vitro lymphocyte proliferation. The results indicate that these preparations strongly inhibit DNA synthesis in stimulated human peripheral lymphocytes, bone marrow cells, thymocytes and lymphoblastoid cells. This inhibition was dose-dependent and not due to cytotoxicity of the preparations. No inhibition was found of the spontaneous proliferation of HeLa cells and human fibroblasts indicating that the inhibitory effect was specific for proliferating lymphocytes. Control preparations from bovine liver or kidney did not show any suppression in the test systems used.

Bone Marrow Cells↗
PubMed1990

Beneficial effects of the thymic hormone preparation thymostimulin in patients with defects in cell-mediated immunity and chronic purulent rhinosinusitis. A double-blind cross-over trial on improvements in monocyte polarization and clinical effects.

Twenty patients with chronic purulent rhinosinusitis were treated with TP-1 (Serono; 1 mg/kg body weight), in a double-blind cross-over trial. TP-1 was administered by daily i.m. injections for the first 14 days followed by two injections/week for 6 further weeks. The patients were immunologically special in that they had defects in their cell-mediated immune system. Fourteen showed a decreased chemotactic responsiveness of their peripheral blood monocytes as measured in the polarization assay. This defective function can probably be ascribed to the presence in serum of low molecular weight factors (LMWFs; less than 25 kD). As reported earlier, this factor shows a structural homology to the envelope protein of murine and feline leukaemia virus (P15E). Thirteen patients showed a defective delayed-type hypersensitivity (DTH) skin test reactivity towards candidin and/or streptokinase-streptodornase (Sk/Sd) antigen, 14 had a defective MIF production from their peripheral blood lymphocytes towards candidin, Sk/Sd and/or Haemophilus influenzae antigen. Eighteen patients completed the TP-1 trial and showed clinical improvements: 12 out of 15 were feeling better during TP-1 therapy and the nasal mucosa showed on inspection absent mucopurulent secretion in 13 patients. Positive bacterial culture rates for the nose decreased from 14 out of 16 to five out of 15. Placebo treatment had no significant effects. The clinical improvements were accompanied by a better performance of the cell-mediated immune system; the most significant effects were recorded in the monocyte polarization assay. The suppressive P15E-like LMWFs in serum clearly decreased during TP-1 treatment. In vitro TP-1 neutralized the immunosuppressive effect of the LMWFs. The restoring effects of TP-1 on monocyte polarization and its neutralizing activity of P15E-like LMWFs could explain the beneficial effects of thymic hormone treatment reported in adults with clinical signs of immunodeficiency in the presence of a full T cell repertoire.

Adult↗