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At least 973 records · Page 54Linked to original sources
PubMed1997

Thymostimulin increases natural cytotoxic activity in patients with breast cancer.

The effect of thymostimulin on the Natural Killer (NK) cytotoxic activity of peripheral blood mononuclear cells (PBMC) was investigated in 15 patients with breast cancer after finishing or during chemotherapy (CAF) and in 10 healthy controls. PBMC from these subjects were incubated in the presence of thymostimulin for varying periods of time (18 h or 5 days), and then used as effector cells against 51Cr-radiolabeled NK-sensitive (K-562) and NK-resistant (JY) target cells in cytotoxicity assays. No significant differences were observed between the NK-activity from breast cancer patients and healthy controls. Thymostimulin induced a dose- and time-dependent cytotoxic enhancing effect on the cytotoxic activity of PBMC from these patients against NK-sensitive K562 target cells. The thymostimulin (1000 ng/ml) significantly enhanced cytotoxic activity in PBMC from breast cancer patients who had previously received chemotherapy (p = 0.0277) against NK-sensitive cells. This increase was not statistically significant neither in PBMC from patients receiving chemotherapy nor in healthy controls (p > 0.05 in both cases). The incubation of PBMC from patients with breast cancer was not associated to a significant enhancement of the cytotoxic activity against NK-resistant target cells (p > 0.05). We also found that thymostimulin could synergize with interleukin-2 in inducing NK cytotoxic activity in PBMC after 18 h of culture (p = 0.0277). In conclusion, we have demonstrated that thymostimulin enhances the natural killer cytotoxic activity of PBMC from patients with breast cancer who have previously received chemotherapy.

Adjuvants, Immunologic↗
PubMed1990

Insulin requirements and residual beta-cell function 12 months after concluding immunotherapy in type I diabetic patients treated with combined azathioprine and thymostimulin administration for one year.

An increase in clinical and functional remissions with immunosuppression, as well as abnormal T-cell function, in Type I diabetic patients has been reported in the early stages of diabetes. A controlled trial with azathioprine and thymostimulin in separate and combined administration was performed in 45 recently diagnosed Type I diabetic patients. Phenotyping of the T-lymphocyte subsets, levels of CD25 positive cells and interleukin-2 production by patients' lymphocytes, as well as remission rate and stimulated C-peptide levels, were serially assessed. Remission was defined as mean weekly glycemic profiles less than or equal to 7 mmole/l, serial HbA1 values in the normal range and no insulin requirements for at least 2 consecutive months. At 3,6,9 and 12 months of immunotherapy, remission occurred respectively in 0%, 8.3%, 16.6% and 0% of the conventionally treated diabetic controls and in 42.8%, 50%, 42.8% and 36.2% of the subjects submitted to combined azathioprine and thymostimulin administration. Patients receiving azathioprine or thymostimulin alone did not achieve better remission rates than controls. C-peptide levels were significantly higher (above 0.6 pmol/ml) in patients with remission than in those not in remission (P less than 0.02) throughout the trial. Excessive interleukin-2 production in recently diagnosed diabetics returned to normal levels in patients in remission. In the group receiving combined therapy, 38.5%, 25% and 23% were still in clinical remission at 6, 9 and 12 months after drug withdrawal. Twelve months after stopping treatment, patients who had remitted exhibited significantly lower insulin requirements and greater endogenous insulin secretion than those who had not remitted; the former also maintained near normal glycemic control. No side effects were detected except mild and transient leucopenia in a reduced number of patients receiving azathioprine. Remission was related to the time of beginning immunotherapy after the onset of diabetes (17.1 +/- 7 vs 42.5 +/- 15 days; P less than 0.01) and to age (17.7 +/- 5.6 vs 13 +/- 7 years; P less than 0.05). Interleukin-2 production seems to be negatively associated with clinical remission in the early stages of diabetes. Results suggest a complementary effect of the drugs used in this study that may enhance long-term remission in recently diagnosed Type I diabetic patients.

Adolescent↗
PubMed2002

Understanding the congener-specific toxicity in polychlorinated dibenzo-p-dioxins: chlorination pattern and molecular quadrupole moment.

It is well known that the biological activities and toxicities of planar polychlorinated aromatic compounds are extremely sensitive to chlorination pattern. Although their toxic responses have been correlated with the relative affinity for the receptor, the origin of this congener specificity is not well understood. We present a general interpretation of the congener-specific activity in polychlorinated dibenzo-p-dioxins, which concludes that molecular electrostatics is the principal factor determining the structure-activity relationship in this highly controversial environmental pollutant even though this electrostatic interaction represents only a part of the total interaction energy. Through calculations of the molecular charge distribution in the complete set of 76 dioxin congeners, we show that all active congeners share a unique charge distribution pattern, which is quantitatively described in terms of the molecular quadrupole moment (QM). The QM of dioxins changes sensitively and systematically with chlorination pattern. The three-dimensional electrostatic interactions at the receptor-binding site, which are optimized at a specific QM pattern represented by that of 2,3,7,8-tetrachlorodibenzo-p-dioxin, could explain the congener specificity in the binding affinity and toxicity. Although the polarizability also changes systematically with chlorination, it can only account for the effect of the degree of chlorination, not the congener specificity.

Environmental Pollutants↗
PubMed2005

Modulating effects of thyme and its major ingredients on oxidative DNA damage in human lymphocytes.

The present study was carried out to investigate the modulating effects of thyme and its major components against the oxidative DNA damage induced by H(2)O(2). The human lymphocytes with thymol, carvacrol, and gamma-terpinene incubated with or without 0.1 mM H(2)O(2) for 30 min at 37 degrees C and the DNA damage were evaluated by singe cell gel electropheresis (comet assay). Concentrations above 0.1 mM thymol and gamma-terpinene and 0.05 mM carvacrol significantly induced DNA damage in human lymphocytes, but at the smaller concentrations no additional DNA strand breakage has been observed. At the all concentrations studied, gamma-terpinene did not show any protective effect against H(2)O(2) induced oxidative DNA damage, but the phenolic compounds thymol and carvacrol at concentrations below 0.2 and 0.1 mM, respectively, significantly reduced the oxidative DNA damage (p < 0.001). The n-hexane and ethyl acetate fractions prepared from the methanolic extracts of Thymus spicata also were found to inhibit DNA damage.

Cyclohexane Monoterpenes↗
PubMed2003

Suppression of natural killer cells after acute intoxication with alcohols and cholinotropic preparations and their reactivation with T-activin.

Acute poisoning with alcohols and cholinotropic preparations carboxyphosphamide and atropine (0.8 LD(50)) was modeled on male outbred mice weighing 18-24 g. The decrease in activity of natural killer cells was most pronounced after injection of atropine, but insignificant after treatment with ethanol. The inhibitory effect of ethylene glycol, methanol, and methanol on functional activity of natural killer cells in vitro directly depended on their concentration. The effects of alcohols in equimolar concentrations of 10, 100, and 500 mM were similar. Therefore, immunotoxicity of alcohols was associated with the action of their metabolites. The ability of products formed after biotransformation of ethylene glycol, methanol, and ethanol in equimolar concentrations to cause damage to natural killer cells decreased in the following order: glyoxylic acid>formic acid>acetaldehyde>glycolaldehyde>glycolic acid. T-Activin injected subcutaneously in doses of 2.5 and 5.0 microg/kg for 3 days normalized activity of natural killer cells suppressed after acute poisoning with alcohols and cholinotropic preparations.

Acute Disease↗
PubMed2003

An oligosaccharide fraction from Korean mugwort herb suppresses death of the mouse thymocytes in culture by down-regulating the Fas death receptor gene.

Korean mugwort herb is a preparation of dried leaves from Artemisia species and has been used as a traditional medicine in Asia. An oligosaccharide fraction, AVF3, purified from the preparation promoted survival of the mouse thymocytes in culture. A mouse gene array study suggests that the AVF3 may modulate Fas/FasL dependent apoptotic cell death and thus has influence on the survival of the thymocytes in culture. RT-PCR analysis confirmed the down-regulation of the Fas gene by the AVF3 treatment, supporting that the AVF3 modulated thymocyte death by suppressing the Fas gene expression.

Animals↗
PubMed2004

Effects of T-activin and vitamin E on toxicity and antitumor activity of cyclophosphamide.

We studied the effect of combination treatment with T-activin and vitamin E on acute toxicity and antitumor activity of cyclophosphamide in mice. Combined administration of these preparations 1.37-fold increased the maximum permissible dose of cyclophosphamide without affecting its LD(50)and delayed mouse death from cyclophosphamide toxicity. Most mice died only 3 days after combination treatment with the test preparations and cyclophosphamide in doses of LD(16)-LD(84). The second peak of death from hematologic toxicity of cyclophosphamide was absent under these conditions. T-activin and vitamin E did not abolish the antitumor effect of cyclophosphamide on mice with subcutaneously implanted P-388 lympholeukemia. Tumor growth was suppressed by 100%.

Animals↗
PubMed1996

The effects of thymostimulin on immunological function in patients with head and neck cancer.

Patients with head and neck carcinoma show deficits of cellular immunity, probably due to low molecular mass factors (LMMFs) released by the tumour. Thymostimulin (TP1) restores the defective monocyte chemotaxis and dendritic cell clustering capability in the presence of the tumour when administered pre-operatively. In the present study we investigated these immune parameters in 39 patients treated with TP1 for 10 days pre- and 6 months post-operatively and in 22 patients who were not treated with TP1 for 6 months after operation. Removal of the tumour in non-TP1-treated patients also resulted in a restoration of monocyte and dendritic cell functions, while TP1 treatment gave no additional effect. LMMF levels in the blood of both TP1-treated and non-TP1-treated patients remained elevated even after removal of the tumour, and it is therefore concluded that it is unlikely that depression of cellular immunity is a direct effect of these LMMFS.

Adjuvants, Immunologic↗
PubMed1979

Cholesterol and triglycerides of the liver after administration of a chromatographic fraction of thymus: variations in tissue and blood.

In rats fed on a fat diet and injected with a chromatographic thymus fraction, intrahepatic distribution of cholesterol and triglycerides have been studied. The results show that the hematic decrease of these compounds, always observed in previous works, is accompanied by a smaller infiltration in hepatocytes and the lipidic drops are more finely dispersed. These results lead us to suppose that liver is a target organ of the thymus fraction.

Animals↗
PubMed2003

[Systemic treatment for hepatocellular carcinoma].

Hepatocellular carcinoma (HCC) is one of the most frequent malignancies worldwide. A variety of pharmacological strategies has been evaluated in the treatment of HCC: classical chemotherapy, tamoxifen, octreotide, thymostimulin, pravastatin, (131)I-lipiodol as well as transarterial chemoperfusion (TAC) and chemoembolisation (TACE). TACE monotherapy or TACE combined with pravastatin resulted in a survival benefit of selected HCC patients. New strategies such as immunotherapy, antiangiogenic agents or cyclooxygenase inhibitors are under clinical investigation and might play a role in future therapies for HCC. Efficient strategies for the primary prevention of HCC are available and promising concepts in the secondary prevention have been reported.

Adjuvants, Immunologic↗
PubMed1987

The serum apo B and apo E in rats following cholesterol diet and thymus treatment.

The serum levels of apo B and apo E in rats fed on a diet rich in cholesterol before and after thymus treatment were determined by the authors. The diet enriched with cholesterol increases the serum levels of apo E and of the large and small species of apo B. After treatment the large apo B and the small one strongly decrease, while apo E increases further. These data support the hypothesis that the dropping of total cholesterol, after thymus treatment, cannot be ascribed to apo E decrease but possibly to B-apoproteins.

Animals↗