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51.
Maurizio Rossetto Kingsley W. Dixon Eric Bunn 《In vitro cellular & developmental biology. Plant》1992,28(4):192-196
Summary Aeration of tissue cultured rare Australian plantsConostylis wonganensis S.D. Hopper (Haemodoraceae);Diplolaena andrewsii Ostenf.;Drummondita ericoides Harvey (Rutaceae);Eremophila resinosa F. Muell. (Myoporaceae);Eucalyptus ‘graniticola’ (Myrtaceae);Lechenaultia pulvinaris C. Gardner (goodeniaceae); andSowerbaea multicaulis E. Pritzel (Liliaceae) has been found to reduce vitrification in sensitive species as well as significantly improving shoot
quality and transfer to soil in most study species. A simple 7-mm hole with a double-layer insert of filter paper in the polypropylene
screw lids of the culture vessel decreased shoot vitrification over a 4-wk culture period. The method has implications for
facilitating the tissue culture of other rare Australian plants and reducing the occurrence of this developmental abnormality. 相似文献
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53.
The value of Y-body study for assessment of stromal cell engraftment was analyzed in 25 patients submitted to allogeneic bone marrow transplantation (BMT) (sex-matched in 12 cases and sex-mismatched in 13). The study was performed weekly on bone marrow smears until day +35, and the results were compared with those obtained in a control group of 20 patients submitted to autologous BMT (12 males and 8 females). Engraftment of haemopoietic cells was documented in all cases. The results of Y-body study on the recipients' fibroblast cells showed a pattern identical to that observed prior to BMT, independent of donor's sex. On the other hand, there were no differences between allogeneic and autologous BMT recipients in regard to percentage of Y-body positive cells. These results indicate that in allogeneic BMT there is no engraftment of the fibroblastic component of bone marrow stroma. 相似文献
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55.
Giuseppe Fossati Andrea Balsari Donatella Taramelli Maria Luisa Sensi Giuseppe Pellegris Maurizio Nava Giorgio Parmiani 《Cancer immunology, immunotherapy : CII》1982,14(2):99-104
Summary Peripheral blood lymphocytes (PBL) of melanoma patients were sensitized in vitro with lymphocytes of a single donor or with a pool of lymphocytes of 5–20 different donors. After 6–7 days, the cytotoxic activity of the sensitized PBL was tested against cultured autologous tumor cells and lymphocytes in a 51Cr-release assay. Tumor lysis was observed in 13 of 16 cases in which patients' PBL (Pt-PBL) were stimulated by a pool of allogeneic lymphocytes and in five out of seven cases when single sensitization was performed. In no case was lysis of autologous normal lymphocytes or blasts seen. Cultivation of Pt-PBL with irradiated autologous tumor cells never led to the induction of lymphocytes cytotoxic to melanoma cells. Lysability by pool-activated autologous Pt-PBL of fresh cryopreserved tumor cells was compared to that of short-term cultured tumor cells, and no significant differences were observed. Cold-target inhibition experiments indicated that the cytotoxicity of Pt-PBL was tumor-restricted since only autologous melanoma cells but not lymphocytes were able to inhibit the reaction. These results indicate that activation of Pt-PBL is necessary in order to elicit or amplify their antitumor activity. 相似文献
56.
George W. Arana Ross J. Baldessarini Michael Herschel Maurizio Fava 《Life sciences》1981,29(2):121-133
The binding of low concentrations of [3H](?)apomorphine to preparations of calf and rat forebrain tissue was evaluated. Fractionation of crude homogenates to prepare a membrane fraction (P4) of striatal or caudate homogenates increased the proportion of saturable to total binding from 33% to over 80%, and increased the apparent density of binding sites from 94 to 681 fmol/mg protein. Binding in calf caudate P4 tissue was protein-dependent and optimal at pH = 7.0 to 7.5, and T = 20 to 25°C; at higher temperatures tissue binding sites appeared to degrade. The half-time of association and dissociation at 22°C were, respectively, 14.0 and 18.5 min; equilibration was complete in 60 min. Kinetic characteristics of high-affinity binding obtained from association and dissociation constants and from saturation isotherms were similar (Kd = 2.1 to 3.4 nM). The pharmacology of competition for 3H-APO suggests selectivity for dopamine-agonist interactions. These results indicate that the P4 membrane preparation may be useful for the evaluation of dopamine-agonist binding sites or “receptors.” 相似文献
57.
Andreas Gescher Maurizio DIncalci Roberto Fanelli Pierluigi Farina 《Life sciences》1980,26(2):147-154
N-Hydroxymethylpentamethylmelamine (HMPMM) was identified by HPLC and by GLC-MS after derivatization, as a metabolite of the anticancer drug hexamethylmelamine (HMM) in incubation mixtures with fortified mouse liver 9000 × g and microsomal preparations. HMPMM formation was dependent on the presence of NADPH and oxygen. N-demethylated metabolites were also found. HMPMM displays appreciable chemical stability and 29% was recovered after 60 min incubation in buffer. HMPMM constituted more than 50% of total HMM metabolites in 30 min incubations. The known chemical reactivity of carbinolamines means that HMPMM could be involved in the pharmacological or toxic effects of HMM. 相似文献
58.
The carrier-mediated transport of GABA in rat brain synaptosomes was strongly and permanently inhibited byl-2,4-diaminobutyric acid (DAB). In order to discriminate between carrier-mediated and non-carrier-mediated release of [3H]GABA, synaptosomes prelabeled with 0.5 M [3H]GABA in the presence of 100 M DAB, or with 0.2 M [3H]GABA without DAB, were superfused in conditions stimulating the release of [3H]GABA. Only the release elicited by unlabeled GABA or DAB (by homo- and heteroexchange, respectively) was strongly inhibited in DAB-pretreated synaptosomes. The spontaneous release and the release induced by 56 mM KCl in the presence of CaCl2, by the ionophore A23187, by ouabain, by lack of K+, or by purified black widow spider toxin were unaffected or only barely decreased in DAB-treated synaptosomes, and therefore do not seem to be mediated by the DAB-blocked GABA carrier. 相似文献
59.
The effects of the ionophore A23187 and of ouabain on the release of [3H]GABA and [3H]norepinephrine were studied in superfused rat brain synaptosomes. Each of the two drugs moderately stimulated the spontaneous release of [3H]GABA, but greatly potentiated the release of [3H]GABA induced by unlabeled GABA. In contrast, the ionophore and norepinephrine showed an additive, but not a supraadditive, releasing effect on synaptosomal [3H]norepinephrine. Ouabain modestly and transiently potentiated the norepinephrine-induced [3H]norepinephrine release, which, however, was inhibited by the drug after a few minutes. It is suggested that in the new intrasynaptosomal ionic conditions determined by the two drugs, the stoichiometry of the basal homoexchange of GABA is changed in a direction favoring net outward transport. 相似文献
60.