Showing papers by "Libera! published in 2000"
TL;DR: Postoperative administration of low-dose cyclic oral contraceptives does not significantly affect the long-term recurrence rate of endometriosis after surgical treatment, and a delay in recurrence is evident at life-table analysis.
124 citations
TL;DR: Ascorbate content and the activities of some key enzymes involved in the detoxification from reactive oxygen species were investigated in germinated embryos of two Zea mays L. inbred lines and of their heterotic F1 hybrid, which showed a higher ascorbate biosynthetic capability.
Abstract: Ascorbate content and the activities of some key enzymes involved in the detoxification from reactive oxygen species were investigated in germinated embryos of two Zea mays L. inbred lines (B73 and Mo17) and of their heterotic F1 hybrid (B73×Mo17). The F1 hybrid showed a higher ascorbate biosynthetic capability owing to a higher activity of l-galactono-Γ-lactone dehydrogenase (EC 1.6.5.4), the last enzyme in ascorbate biosynthesis. Ascorbate peroxidase (EC 1.11.1.11), ascorbate free radical reductase (EC 1.6.5.4) and dehydroascorbate reductase (EC 1.8.5.1) activities were much higher in the F1 hybrid than in either inbred line, whereas catalase (EC 1.11.1.6) activity was similar in the three genotypes. Native polyacrylamide gel electrophoresis (PAGE) analysis showed three forms of cytosolic ascorbate peroxidase, both in parental lines and in the F1 hybrid. On the other hand, a complex pattern of proteins with dehydroascorbate reductase activity was observed, with the hybrid combining the different dehydroascorbate-reducing proteins expressed by the inbred lines. The possible involvement of the enzymes of the ascorbate system in the phenomenon of hybrid vigour is discussed.
99 citations
TL;DR: The behaviour of the ASC and GSH recycling enzymes allowed TBY-2 cells to maintain both dehydroascorbic acid and glutathione disulphide at low levels, even under conditions of high ASC andGSH utilisation.
97 citations
TL;DR: Results challenge the current view that induction of oral tolerance can be established when the immune process is already active and show that oral insulin administration at the dose of 5 mg daily for one year starting at the time of disease onset had no effect on residual beta‐cell function as assessed by C‐peptide secretion.
Abstract: Induction of tolerance to insulin, the only beta-cell-specific antigen in Type 1 diabetes, is under testing for prevention of Type 1 diabetes in the US multicentre trial DPT1. Recently a multicentre double-blind trial with oral insulin in patients with recent onset Type 1 diabetes, conducted by our group, has been completed and showed that oral insulin administration at the dose of 5 mg daily for one year starting at the time of disease onset had no effect on residual beta-cell function as assessed by C-peptide secretion. A similar trial using different doses was carried out at the same time and similarly showed no beneficial effect on the decline of beta-cell function during the first year after diagnosis. In this study oral insulin was administered at the daily doses of 2.5 and 7.5 mg over a one-year period. Such results challenge the current view that induction of oral tolerance can be established when the immune process is already active. Copyright © 2000 John Wiley & Sons, Ltd.
22 citations
TL;DR: It is suggested that antiviral activity of PI could be modified by the expression of a protein P-gp that has been demonstrated to be able to bind PI and is involved in extrusion of anticancer agents.
17 citations
TL;DR: It is suggested that uninfected PBMC can undergo activation of signal transduction and apoptosis after exposure to bystander HIV‐infected cells, subsequent to the induction of cytokines such as IFNs and TNF‐α.
Abstract: SUMMARY Persistent activation of the immune system is one of the hallmarks of HIV-1 infection. In this study we analysed the induction of factors involved in cytokine signal transduction, such as STAT 1 proteins and IRF-1 mRNA, in normal peripheral blood mononuclear cells (PBMC) exposed to HIV-infected cells, and the induction of apoptosis. Western blot analyses and reverse transcriptase-polymerase chain reaction results indicate that both cells infected with a X4 strain and cells infected with a R5 strain are able to increase intracellular levels of STAT 1a and b proteins as well as IRF-1 mRNA. This effect was prevented by neutralizing antibodies against interferon-alpha (IFN-a ). HIV-1-infected cells dosedependently induced apoptotic commitment in normal PBMC, as revealed by DNA fragmentation analysis, but this was not accompanied by an increase of caspase-3 activity, even if a slight up-regulation of IL-1b -converting enzyme mRNA was detected. Apoptosis induction could be abrogated mainly by antibodies against tumour necrosis factor-alpha (TNF-a ) and, to a lesser extent, by antibodies against IFN-g. All these findings suggest that uninfected PBMC can undergo activation of signal transduction and apoptosis after exposure to bystander HIV-infected cells, subsequent to the induction of cytokines such as IFNs and TNF-a .
14 citations