摘要:

AbstractA single i.p. injection of cisplal-in (10 mg/kg body weight) into mice results in a significant increase in chemiluminescence and ATP contents of the peritoneal exudate cells (PEC) than that of PEC from untreated mice. It is also observed that in vitro treatment of macrophages with cisplatin, rIFN-γand LPS show increased activity of the protein kinase-C.(PK-C). the activation of PK-C could result in stimulation of NADPH-oxidase resulting in increased levels of chemi luminescence. Increased contents of ATP in PEC after cisplatin treatment also suggests that this activation is energy dependent.

ISSN:0892-3973    

DOI:10.3109/08923979109019687

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractBecause of the national epidemic of cocaine abuse and the increasing prevalence of infectious diseases among drug abusers, we investigated the effects of cocaine and cocaine metabolites on human cellular immune functions. Mononuclear cells (MNC) were isolated from blood of healthy adult volunteers. MNC were stimulated in vitro with mitogens with and without various concentrations of cocaine. Because of cocaine's poor stability in vitro, we found it necessary to replenish cocaine daily to MNC cultures. Under these conditions, cocaine, in a dose response fashion, significantly inhibited MNC proliferation: Metabolites of cocaine did not alter MNC proliferative responses significantly from control cultures. Polymorphonuclear leukocyte chemotaxis was also significantly impaired by cocaine. Our data demonstrate that cocaine is immunosuppressive and that it acts on human MNC during early stages of cellular activation. These data further suggest that illicit cocaine use may compromise the integrity of the immune system.

ISSN:0892-3973    

DOI:10.3109/08923979109019688

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

Abstract1, l-Dimethylhydrazine or unsymmetrical dimethylhydrazine (UDMH) is a highly volatile and reactive compound used primarily as a liquid rocket propellant. Previous studies found UDMH to possess immunomodulatory activity similar to other hydrazine derivatives. Modulation of T lymphocyte subpopulations and Major Histocompatibility Complex Class II or la antigen were evaluated as possible mechanisms for this UDMH-induced immunomodulation. Murine lymphoid cell populations were examined by flow cytometry for changes in their cell surface marker percentages or relative number upon exposure to UDMH eitherin vitroorin vivo. the results show UDMH caused significant suppression of the T helper cell population derived from the thymus at the 75 mg/kg dosein vivo, but did not affect other lymphocyte subpopulations isolated from mesenteric lymph node, spleen or thymus at this or any other dose.In vivoexposure of mice at all doses of UDMH did not significantly alter expression of la antigens on adherent cell populations and expression of the la antigen followingin vitroUDMH exposure was not affected as well. Results indicate that the immunomodulatory effects of UDMH are not mediated by phenotypic alteration of T lymphocyte subpopulations or la antigen.

ISSN:0892-3973    

DOI:10.3109/08923979109019689

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractSeven-week-old male Sprague-Dawley rats were given a single injection of 1.5 mg of 3–methylcholanthrene (3MC) to inducein situfibrosarcomas. the rats were also treated with the dopamine agonist bromocriptine (BCR) from two days prior to 14 days after 3MC treatment and again for 14 consecutive days beginning at week 5. Tumor incidence was markedly increased and latency decreased in BCR-3MC rats compared to 3MC controls. Natural killer (NK) cell cytotoxicity responses and production of interleukin 2 (IL2) was enhanced at two weeks in rats treated with only BCR. Natural killer cell activity was suppressed at two weeks in rats treated with only 3MC. This effect was reversed by BCR treatment. Rats treated with 3MC and BCR had suppressed NK cell responses and production of IL2 and interferon-γ(IFN) at 12 weeks.In another study, rats injected with 1, 3 or 5 mg/kg BCR for 14 consecutive days had increased NK cell activity and IL2 production at all doses and increased IFN production at the two high doses. Antibody (IgG) responses to an injected antigen and delayed-type hypersensitivity reactions were not affected by BCR treatment. Animals treated with the two high doses of BCR had decreased serum prolactin (PRL) levels. Serum growth hormone (GH) concentrations were markedly increased in the group treated with 3 mg/kg BCR.These data suggest that BCR enhances 3MC-induced tumorigenesis. the mechanism of this effect is apparently not mediated by suppression of the immune system since BCR-treated rats had selectively enhanced immune function. Enhancement of immune responses by BCR has not been previously reported.

ISSN:0892-3973    

DOI:10.3109/08923979109019690

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThe effect of tranilast, an inhibitor for IgE-mediated mediator release from mast cells, on plasma extravasation induced by the intradermal injection of substance P in rats was examined. Tranilast (100 mg/kg, intraperitoneally) decreased plasma extravasation induced by substance P (10−-7-−10−-5M). Tranilast decreased plasma extravasation induced by the amino-terminal peptide substance P1–9(10−-6-−10−-4m), which is active for rat mast cells, but not by the carboxy-terminal peptide substance P6–11 (10−-6-−10−-4M), which is inactive for the mast cells. Therefore, tranilast prevents substance P-induced plasma extravasation most likely by inhibiting mast cell degranulation.

ISSN:0892-3973    

DOI:10.3109/08923979109019691

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractWe have studied the effect of pertussis toxin (PT) onin vivopriming of T lymphocytes to insulin. Mice were immunized with bovine insulin in complete Freund's adjuvant and antigen-specific DNA synthesis was measured in lymphoid cell suspensions from lymph nodes and spleens. Insulin-specific response was greatly enhanced both in spleen and lymph nodes if mice were given PT at the time of immunization. Mice given PT presented 3 times more cells in spleen and 4 times less in lymph nodes. However, the major antigen-specific response was still observed in lymph nodes. PT had a strong mitogenic effectin vitroon lymph node cells but a weak effect on spleen cells indicating that the adjuvant activity of PT involves other effects besides the mitogenic activity.

ISSN:0892-3973    

DOI:10.3109/08923979109019692

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractDuring the last few years, several observations outline that the impaired T lymphocyte proliferative capacity in the elderly is due to a reduced interleukin 2 (IL-2) release. to further investigate the activation process during lectin stimulation, aged peripheral blood mononuclear cells (PBMC) were stimulated with phytohemagglutinin (PHA) and assessed for CD25 (IL-2 receptor) and CD71 (transferrin receptor) expression at different intervals of time. Our results provided evidence for a significant decline of both structure induction, above all in the later phase of culture. Indomethacin (INDO) treatment gave rise to an enhancement of CD71 antigen expression only, while prostaglandin E2 (PGE2) supplementation to culture media further decreased either CD25 or CD71 receptor induction. Interferon (IFN)-αand IFN-γtreatment failed to modulate the frequency of CD25+and/or CD71+cells. Finally, the expression of CD71 receptor was increased by deferoxamine supplementation, this suggesting a partial involvement of iron overload in the depressed function.Although further studies are required to evaluate at a molecular level the decreased antigen expression, these findings indicate that several mechanisms are involved in the elderly-related decline of T lymphocyte activation structures during lectin stimulation.

ISSN:0892-3973    

DOI:10.3109/08923979109019693

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractA pharmacokinetic profile of14C-AdDP with uniformly labelled alanine was investigated. It was shown that the distribution phase after an i.v. administration is very short with a half-life of 2.1 min. the half-life of elimination phase after the i.v. administration is about 2.85 hours, that is longer than those of MDP and its derivatives. the total body clearance (30 ml/min/kg) is caused predominantly by metabolism of the compound. All the radioactivity found in urine in a 48 hours interval after a s.c. administration represents only 3.1% of the administered dose. Only a smaller part of the excreted radioactivity is formed by unmetabolised AdDP. the concentration curve after a S.C. administration is characterized by a very fast absorption with a half-life shorter than 1 minute. the distribution and elimination phases are prolonged (20 min, 11 hours respectively) in comparison with an i.v. injection. the decreased absolute bioavailability after a s.c. administration (65%) is probably not biologically significant because of a slower release of the compound from the site of the S.C. administration. A relatively very high radioactivity was found in liver, kidney, thymus, spleen and brain very soon which suggest a very good penetration into tissues. It is an agreement with the high apparent distribution volume of peripheral compartment and higher lipophilicity of AdDP as compared to MDP.

ISSN:0892-3973    

DOI:10.3109/08923979109019694

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

Abstract(4R)-Hexahydro-7, 7–dimethyl-6–oxo-1, 2, 5–dithiazocine-4–carboxylic acid (SA3443) is a newly synthesized cyclic disulfide compound which offers potential hepatoprotective properties.The effect of SA3443 on the induction of natural killer (NK) and cytotoxic T lymphocyte (CTL) activities was investigated. NK activity in BALB/c mice splenic cells was investigated using YAC-1 cells as target cells. SA3443, at a dose range of 30–300 mg/kg/day, augmented NK activity significantly when administered orally once daily for 4 days before the assay. Alloantigen-specific CTL activity in splenic cells from BALB/c mice was detected 9 days after sensitization with C57BL/6 mice splenic cells. SA3443, at a dose of 100 mg/kg/day, augmented CTL activity significantly when administered orally, once daily for 4 days beginning after the sensitization and for 2 days before the assay, while a high dose of SA3443, at 300mg/kg, suppressed CTL activity.From these results, it is thought that SA3443 may assist in the elimination of hepatitis viruses from the liver in patients with chronic active hepatitis, by the activation of NK and/or CTL activities.

ISSN:0892-3973    

DOI:10.3109/08923979109019695

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractAcetyl-L-carnitine (ALC), a drug for the treatment of ageing-related neuroendocrine dysfunctions, was orally administered -2 gm/day for 30 days -to 10 patients with active pulmonary tuberculosis (TBC). Lymphocyte-mediated antibacterial activity and serum levels of tumor necrosis factor (TNF)-U were evaluated before and after treatment, comparing the values with those of 10 TBC patients receiving placebo.Results show that by day 30, antibacterial activity remained unmodified or increased in ALC-treated subjects, while decreased in the placebo group. No influence of ALC on TNF-U levels was detectable.These data suggest that the host's immune responses toM. tuberculosisinfection can be selectively modulated by drugs acting on the neuroendocrine axis.

ISSN:0892-3973    

DOI:10.3109/08923979109019696

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor