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PubMed2005

Hystological and pharmacological study of Thymus piperella (L.).

Histological and pharmacological assays have been carried out with methanol, hexane, dichloromethane and butanol extracts of Thymus piperella (L.) leaves. All the extracts were considered innocuo in the toxicity test. Methanol and also hexane, dichlorometane and butanol fractions, inhibited significantly the contractions induced by acetylcholine in isolated rat ileum in a concentration-dependent manner and the hexane extract was the most potent. However, the methanol extract did not modify the contractile effect of noradrenaline and histamine on isolated rat aorta and guinea-pig trachea respectively at the assayed dose (10, 100, 200 microg/mL). These results contribute to explain in part the use of this plant in folk medicine. In addition, morphological and histological structures characteristic of this species have been described for the first time.

Animals↗
PubMed1986

Thymic hormone dependent immunodeficiency in an infant with partial trisomy of chromosome 22.

An infant with partial trisomy 22 syndrome and recurrent infections showed severe cellular immunodeficiency and serum IgG reduction. A marked increase of E-RFCs was observed after in vitro incubation of peripheral blood lymphocytes with thymostimulin (TS), a calf thymic extract. The treatment with TS resulted in reduction of infections, correction of cellular immunodeficiency and increase of IgG levels. Such a primary thymic hormone dependent immunodeficiency may be due to an altered development of branchial arches, commonly present in trisomy 22 syndrome. The same pathogenetic mechanism may account for thymus dysplasia observed in other chromosomal syndromes.

Cells, Cultured↗
PubMed1976

Gallium-67 distribution in pregnant mammals.

Studies on the distribution of 67Ga in pregnant rabbits showed a marked concentration of the isotope in uterine tissue and flushings of 5-day pregnant rabbits 24 hours after isotope injection. The isotope no longer localized throughout the uterine tissues and flushings on injection of 7- to 8-day pregnant rabbits but was specifically associated with the blastocysts and sites of implantation. As the gestation time progressed 67Ga increasingly concentrated in placental and mammary tissue while the concentration in serum and thymus tissue decreased. The marked concentration in placental tissue was readily discernible on total-body scans of pregnant rabbits. Column chromatography of uterine washings and placental extracts from pregnant rabbits and thymus extracts from estrous rabbits showed most of the isotope associated with moieties greater than or equal to 200,000 MW whereas the isotope in "milk" and extracts of mammary tissue was bound to components of 25,000-35,000 MW. Extracts of thymus from pregnant rats showed a marked, selective loss of 67Ga binding in two peaks of approximately 50,000 and 120,000 MW compared to the chromatographic profile of extracts from normal rat thymus.

Animals↗
PubMedDate not supplied

Natrium, potassium, cholesterol and total free 11-hydroxycorticosteroids variations in thymectomized and thymic extract treated rats.

The authors investigated the effect of thymectomy and TP2 thymic polypeptide extract administration on total, esterified and free cholesterol in the plasma and the adrenals, as well as on plasma Na and K and plasma free total 11-hydroxycorticosteroids. The results showed that total, esterified and free cholesterol decrease in the adrenals by 23.20%, 28.57% and 17.70% maximum respectively, in the thymectomized rat and that under the influence of the TP2 extract the values increase by 14.81%, 15.38% and 12.67%, respectively. Plasma cholesterol did not change. Thymectomy caused an increase in the plasma 11-hydroxycorticosteroids value by 13.4% and administration of the TP2 extract lowered their value by 58.11%. The plasma Na and K values did not change.

11-Hydroxycorticosteroids↗
PubMed1986

Immunochemical analysis of mammalian RNA polymerase II subspecies. Stability and relative in vivo concentration.

Three subspecies of RNA polymerase II, designated IIO, IIA, and IIB, have been described in a variety of eukaryotic cells and shown to differ in the molecular weight of their largest subunit, designated IIo, IIa, and IIb, respectively. The objectives of this study were to establish the in vivo molecular structure of RNA polymerase II in mammalian cells and to examine conditions that influence the stability of RNA polymerase II subspecies. Subunit affinity-purified antibodies were used to determine the relative concentration of subunits IIo, IIa, and IIb in crude extracts of calf thymus tissue, cultured bovine kidney cells, and HeLa cells. HeLa cells contain exclusively RNA polymerase IIO whereas both cultured bovine kidney cells and calf thymus tissue contain RNA polymerases IIO and IIA. RNA polymerase IIB was not detected at significant levels in any of the cell extracts examined. Cell extracts were aged at either 4 degrees or 37 degrees C and the stability of RNA polymerases IIO and IIA determined by protein blotting. In the presence of buffer normally used for RNA polymerase purification, subunit IIo disappears from calf thymus extracts within 24 h at 4 degrees C or within 5 min at 37 degrees C. RNA polymerase IIO is partially stabilized by the inclusion of protease inhibitors and further stabilized by the presence of relatively high concentration of EDTA and EGTA. The prior fractionation of nuclei does not have an appreciable effect on RNA polymerase II stability. An increase in the amount of reducing agent causes a dramatic reduction in the stability of subunit IIo. The following manuscript (Bartholomew, B., Dahmus, M. E., and Meares, C. F. (1986) J. Biol. Chem. 14226-14231) examines the transcriptional activity of RNA polymerases IIO and IIA in reactions dependent on the major late promoter of adenovirus-2. Photoaffinity labeling of subunits IIo and IIa, relative to their concentration in the transcription extract, indicates that the transcriptional activity of RNA polymerase IIO is greater than 10 times that of IIA.

Animals↗
PubMedDate not supplied

Influence of the thymic extract (TP2) on some humoral and cell mediated immunity reactions in normal or irradiated animals.

The authors have studied the action of a thymic extract (TP2) containing thymic polypeptides with a molecular weight under 10,000 daltons, on humoral and cell-mediated immunity reactions in normal animals or in animals immunologically depressed by X-ray irradiation. The following were investigated: serum antibodies, such as antiflagelar agglutinins of TH Salmonella and anti-influenza antibodies in the rat, the plaque-forming hemolytic cells in the mouse spleen, delayed hypersensitivity reaction in guinea-pigs innoculated with BCG, the lymphocyte rosetting reaction in the mouse spleen, and the inhibition of macrophages migration in the rats innoculated with TH Salmonella typhi vaccine. The results showed that TP2 stimulates both the humoral and the cell-mediated immunity reactions and has a radioprotecting effect.

Animals↗
PubMed1982

Immunochemical studies on thymosin: radioimmunoassay of thymosin alpha 1.

A sensitive and specific radioimmunoassay (RIA) has been developed to measure thymosin alpha 1 in human blood and tissue extracts. Thymosin alpha 1, originally isolated from bovine thymosin fraction 5, has an identical primary structure in bovine and human species. Antiserum to synthetic thymosin alpha 1 was prepared in rabbits. A synthetic analogue, N-Ac-(Tyr1)thymosin alpha 1 was radioiodinated by utilizing Na125I and soluble lactoperoxidase. The RIA is capable of detecting as small an amount as 40 pg thymosin alpha 1 in serum/plasma and does not significantly cross-react with other putative thymic hormones or other purified blood proteins that have been assayed. Proteolytic degradation of thymosin alpha 1 does not occur during the collection, storage, or assay of serum or plasma. The concentration of thymosin alpha 1 in the blood is highest in utero, decreases sharply after birth, and appears to remain fairly constant during the first 15 yr of life. Maternal blood levels of thymosin alpha 1 appear to be above normal during pregnancy.

Absorption↗
PubMed1983

Thymic hormonal activity on human peripheral blood lymphocytes, in vitro. IV. Proliferative response to allogeneic tumor cells in healthy adults and cancer patients.

A mixed lymphocyte tumor culture (MLTC) assay was used in order to assess thymic hormonal activity on human T-lymphocyte function. Peripheral blood mononuclear cells (PBMC) from 55 healthy subjects and 54 immunodeficient cancer patients were incubated with the thymic extract TP-1, cultured with allogeneic tumor cells (Raji lymphoma or IgR3 melanoma cells) under limiting stimulation conditions and their proliferative response measured by 3H-thymidine incorporation. Mean proliferative response in the cancer group was lower than in the healthy group. TP-1 caused a significant enhancement of mean proliferative response, comparable in the healthy and cancer groups, under all the conditions tested. Analysis of response in the individual cases disclosed a wide scatter of TP-1 effects, including some cases of TP-1 induced suppression. A significant negative correlation between TP-1 effect and level of proliferative response in control was found: enhancement of proliferative response by TP-1 became progressively greater as control proliferative response became progressively lower. A similar pattern was noticed in the cases of TP-1 induced suppression. The negative correlation was similar for the healthy and cancer groups. These results cannot be interpreted in terms of restoration of deficient immune functions, but are compatible with an indirect, regulatory effect of TP-1 on proliferative response, exerted to a comparable degree in the healthy and immunodeficient situations. The possibility that thymic factors regulate normal immune functions, not merely restore deficient functions to normal, may have interesting clinical implications.

Cell Division↗
PubMed1983

Thymic hormonal activity on human peripheral blood lymphocytes, in vitro. V. Effect on induction of lymphocytotoxicity.

Thymic hormonal effect on lymphocytotoxicity induced in vitro and its target specificity were tested using peripheral blood mononuclear cells (PBMC) of healthy subjects. PBMC were treated by the thymic extract TP-1, a similarly prepared spleen extract (SE) or medium only (1 h, 37 degrees C) and then induced to express cytotoxic activity by exposure to allogeneic tumor cells in mixed cultures or by Con A stimulation. The cytotoxicity developed after several days in culture was assayed on 51Cr labelled tumor cells. TP-1 caused a significant mean enhancement of cytotoxicity induced and assayed on Raji lymphoma cells (mean % specific lysis, 31.5 +/- 2.9 without TP-1 and 53.7 +/- 3.6 with TP-1; n = 42; p less than 0.01). The scatter of individual responses to TP-1 was wide, however, and included also some cases of TP-1 induced suppression. Similar wide scatter of TP-1 effects with emphasis on TP-1 induced enhancement was observed with other tumor cell lines or with Con A as inducers. Usually, SE had no effect on induced cytotoxicity. Target selectivity (specificity) of induced cytotoxicity was tested by induction and assay on several tumor cell lines with crossing over, as well as by cold competition assay. When target selectivity was present, it was not masked by TP-1 induced enhancement. Moreover, in some cases, target selectivity became more pronounced after TP-1 treatment. However, TP-1 enhanced also Con A induced non-specific cytotoxicity. No effect of TP-1 on natural killer cell activity of fresh PBMC could be demonstrated. It is suggested that both selective cytotoxicity (T-cell dependent) and non-selective one maybe modulated directly by TP-1 and indirectly by TP-1 modified secondary interactions in culture. This profound regulatory effects could be demonstrated in the PBMC of immune-intact healthy adults.

Cell Line↗
PubMed1989

[Immune reactivity of patients with pulmonary tuberculosis suffering from chronic alcoholism].

The immunological reactivity was studied in 152 patients with pulmonary tuberculosis of whom 112 suffered also of alcoholism. All patients with association of the two diseases showed inhibition of the functional activity and reduction of the number of T-lymphocytes while those without alcoholism showed these changes in 80%. Use of T-activin and electrophoresis of chlorophyllypt allowed to restore the moderately reduced reactivity in most patients. In markedly reduced inhibition of cellular immunity T-activin proved more effective.

Adjuvants, Immunologic↗
PubMed1998

[The use of enzymes in treating patients with malignant lymphoma with a large tumor mass].

Systemic enzymes (wobenzime and wobe-mugos) were approved, that had been prescribed as part of polychemotherapy to 24 patients with malignant lymphomas, who presented with large masses of lymphatic nodes poorly resorbable against the background of polychemotherapy and who were assigned for a high-total dose irradiation, which fact would undoubtedly entail sclerosing of adjacent intact tissues. The use of the enzymes made for the optimum realization of the polychemotherapy effect and permitted avoiding a good many of undesirable side events and complication thereof. The above systemic enzymes are well tolerated by patients; they induce no significant changes in the cellular composition or in blood biochemical indices.

Adjuvants, Immunologic↗
PubMed1996

Study of the post-natal effects of chemopreventive agents on ethylnitrosourea-induced transplacental carcinogenesis in rats. II. Influence of low-molecular-weight polypeptide factors from the thymus, pineal gland, bone marrow, anterior hypothalamus, brain cortex and brain white substance.

The influence of the polypeptide factors extracted from thymus, pineal gland, bone marrow, anterior hypothalamus, brain cortex or brain white substance on N-ethyl-N-nitrosourea (ENU)-induced transplacental carcinogenesis was studied in rats. ENU was given to pregnant rats as a single i.v. exposure at a dose of 75 mg/kg body weight on the 21st day of gestation. The polypeptide factors were given to the offspring as a series of s.c. injections, at a dose of 0.5 mg/rat/day, starting at one or 2.5 months of age and continuing throughout the whole of post-natal life. ENU induced tumors of the brain, spinal cord, peripheral nerves and kidneys in 94-98% of the offspring exposed to the carcinogen, with an average number of 2.3-2.6 tumors per rat, and an average survival time of 294 days. Post-natal thymus factor or pineal gland factor administration was followed by an increase in mean lifespan of approximately 2 months and a significant decrease (P < 0.05) in the total tumor number per tumor-bearing rat, as well as the incidence and multiplicity of spinal cord tumors. Pineal gland factor also decreased the incidence of peripheral nerve and kidney tumors and their number per tumor-bearing rat. Brain cortex factor and brain white substance factor treatment was followed by a decrease in total tumor multiplicity of 1.2- to 3.3-fold, and a decrease in incidence of brain tumors of 10 to 33% per rat in comparison to the controls. Brain cortex factor also decreased the total tumor incidence. At the same time, brain white substance factor administration increased the incidence of peripheral nerve tumors and decreased the mean lifespan. Both bone marrow factor and anterior hypothalamus factor did not have any modifying effects on any of the ENU-induced tumors and mean lifespan. Thus, our results show the possibility of attenuation of transplacental ENU-induced carcinogenesis with post-natal administration of some polypeptide substances.

Animals↗