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In the present study T lymphocytes isolated from a metastatic lymph node (T-LNL) of a melanoma patient have been cloned. In the attempt to verify whether T-LNL may acquire in vitro functional activities in the absence of tumour-associated antigens, they were cloned utilizing allogeneic lymphocytes as feeder cells. Nineteen clones generated from T-LNL proved to be CD4+ and, among these, five were able to kill autologous and allogeneic human melanoma cells in HLA-class-II-restricted way. On the basis of their cytokine production, these CD4+ cytolytic T-LNL clones were shown to belong to the Th0 subset and three of them expersseed the V17 chain of the T cell receptor. These results suggest the presence of melanomaspecific but functionally inactive lymphocytes with T cell receptor oligoclonality in the lymph node environment. These specific T cells may acquire in vitro the capacity to kill autologous and allogeneic tumours without any induction by autologous melanoma cells.  相似文献   
136.
Results of conventional treatment of female non-bacterial recurrent cystitis (NBRC) are discouraging. Most patients show an unexpected high incidence of vaginal candidiasis, while their cell mediated immunity to Herpes simplex viruses (HSV) and Candida antigens seems impaired, and it is known that the persistence of mucocutaneous chronic candidiasis is mainly due to a selective defect of CMI to Canadida antigens. Twenty nine women suffering of NBRC, and in whom previous treatment with antibiotics and non-steroid anti-inflammatory drugs was unsuccessful, underwent oral transfer factor (TF) therapy. TF specific to Canadida and/or to HSV was administered bi-weekly for the first 2 weeks, and then once a week for the following 6 months. No side effects were observed during treatment. The total observation period of our cohort was 24379 days with 353 episodes of cystitis recorded and a cumulative relapse index (RI) of 43. The observation period during and after treatment was 13920 days with 108 relapses and a cumulative RI of 23 (P < 0.0001). It, thus, seems that specific TF may be capable of controlling NBRC and alleviate the symptoms.  相似文献   
137.
Ryanodine receptor (RyR2) is the major Ca2+ channel of the cardiac sarcoplasmic reticulum (SR) and plays a crucial role in the generation of myocardial force. Changes in RyR2 gating properties and resulting increases in its open probability (Po) are associated with Ca2+ leakage from the SR and arrhythmias; however, the effects of RyR2 dysfunction on myocardial contractility are unknown. Here, we investigated the possibility that a RyR2 mutation associated with catecholaminergic polymorphic ventricular tachycardia, R4496C, affects the contractile function of atrial and ventricular myocardium. We measured isometric twitch tension in left ventricular and atrial trabeculae from wild-type mice and heterozygous transgenic mice carrying the R4496C RyR2 mutation and found that twitch force was comparable under baseline conditions (30°C, 2 mM [Ca2+]o, 1 Hz). However, the positive inotropic responses to high stimulation frequency, 0.1 µM isoproterenol, and 5 mM [Ca2+]o were decreased in R4496C trabeculae, as was post-rest potentiation. We investigated the mechanisms underlying inotropic insufficiency in R4496C muscles in single ventricular myocytes. Under baseline conditions, the amplitude of the Ca2+ transient was normal, despite the reduced SR Ca2+ content. Under inotropic challenge, however, R4496C myocytes were unable to boost the amplitude of Ca2+ transients because they are incapable of properly increasing the amount of Ca2+ stored in the SR because of a larger SR Ca2+ leakage. Recovery of force in response to premature stimuli was faster in R4496C myocardium, despite the unchanged rates of recovery of L-type Ca2+ channel current (ICa-L) and SR Ca2+ content in single myocytes. A faster recovery from inactivation of the mutant R4496C channels could explain this behavior. In conclusion, changes in RyR2 channel gating associated with the R4496C mutation could be directly responsible for the alterations in both ventricular and atrial contractility. The increased RyR2 Po and fractional Ca2+ release from the SR induced by the R4496C mutation preserves baseline contractility despite a slight decrease in SR Ca2+ content, but cannot compensate for the inability to increase SR Ca2+ content during inotropic challenge.  相似文献   
138.
Verbascum sinuatum contains, in addition to aucubin and harpagide, four new highly polar iridoid glycosides one of which has been identified as 6-O-β-d-xylopyranosylaucubin on the basis of spectral data and chemical modifications.  相似文献   
139.
From Verbascum sinuatum, besides aucubin, harpagide, 6-O-β-d-xylopyranosylaucubin and sinuatol (6-O- α-l-rhamnopyranosylaucubin), a new iridoid glycoside, sinuatoside, has been isolated and its structure elucidated as 6-O-(3-O-β-d-xylopyranosyl)α-d-galactopyranosyl aucubin on the basis of spectral data and chemical modifications. For the new disaccharide unit of the latter compound the name sinuatose is proposed.  相似文献   
140.
Summary A good correlation was found between in vivo and in vitro responses of peripheral MNC from breast cancer patients and the NK boosting effect of human IFN. In vitro immunochemotherapy studies showed that marked antitumor effects were obtained against cultured cancer cells when a widely used chemotherapeutic agent such as 5-FU was combined with nonsensitized spontaneously cytolytic MNC, preactivated in vitro with IFN. These results suggest that the in vitro susceptibility assay of MNC to IFNs could be used for predicting favorable responses to immunochemotherapy regimens employing IFNs as immunomodulating agents. Abbreviations used: IFN, beta-interferon; CM, complete medium; CTX, cyclophosphamide; E:T ratio, effector target ratio; EDTA, ethylenediaminetetraacetic acid; FCS, fetal calf serum; 5-FU, 5-fluorouracil; IFN, gamma-interferon; Hepes, N-2-hydroxyethylpiperazine-N-2-ethanesulphonic acid IFNs, interferons; KC, killed cells; LDIF, low doses beta-interferon; LU, lytic unit; MAT macrotest; MIT, microtest; MNC, mononuclear cells; MNC/IFN, IFN-pretreated MNC; MTX, methotrexate; NB, no boosting; NK, natural killer; NKA, NK activity; NR, natural resistance; PM, positive modulation; SE, standard error; WM, washing medium  相似文献   
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