Red wine polyphenols cause growth inhibition and apoptosis in acute lymphoblastic leukaemia cells by inducing a redox-sensitive up-regulation of p73 and down-regulation of UHRF1

Several epidemiological studies suggest that a diet rich in fruits and vegetables, which contain high levels of polyphenols, is associated with a reduced risk of cancer. The aim of the present study was to determine whether a red wine polyphenolic extract (RWPs, a rich source of polyphenols; 2.9 g/L) affects the proliferation of human lymphoblastic leukaemia cells (Jurkat cells) and, if so, to determine the underlying mechanism. Cell proliferation and viability were determined by the MTS and trypan blue exclusion assays, respectively. Cell cycle analysis, apoptosis activity and oxidative stress levels were assessed by flow cytometry, and the expression of p73, UHRF1 and active caspase-3 by Western blot analysis. RWPs inhibited the proliferation of Jurkat cells and induced G0/G1 cell cycle arrest in a concentration-dependent manner. Moreover, RWPs triggered apoptosis, which is associated with an increased expression level of the pro-apoptotic protein p73 and the active caspase-3. RWPs induced apoptosis confirmed by DNA fragmentation analysis, and this effect was associated with down-regulation of the antiapoptotic protein UHRF1. Furthermore RWPs significantly increased the formation of reactive oxygen species (ROS). Intracellular scavengers of superoxide anions (MnTMPyP, MnTBAP, PEG-SOD) prevented the RWPs-induced formation of ROS and apoptosis, while native extracellular superoxide dismutase (SOD) was without effect. In addition, the effect of RWPs on the expression levels of p73, active caspase-3 and UHRF1 was also prevented by MnTMPyP. Thus, these findings indicate that RWPs induce apoptosis in Jurkat cells by a redox-sensitive mechanism involving the intracellular formation of superoxide anions and consequently the up-regulation of p73 and down-regulation of UHRF1.     

Intracavernous injections in the treatment of erectile dysfunction in spinal cord injured patients: experience with 36 patients]

OBJECTIVES: To confirm the efficiency of intracavernous injections in the treatment of erectile dysfunction in spinal cord injured (SCI) patients and to determine the mean necessary dose to obtain functional erection. MATERIALS: This prospective study concerns 36 spinal cord injured men. None of them had erectile dysfunction before the neurologic impairement. Sixty four intracavernous injections were performed.Method: The first injection was done with the usually recommended starting dose. The injections were then repeated with increasing dosage to archive a rigid erection. The erection was evaluated with Schramek grading. A grade 4 or 5 erection was considered as functional. RESULTS: Nine tetraplegics and 27 paraplegics were included. Twenty two were grade A in ASIA classification. The mean age was 31 years. Twenty for patients had a level above T10, 11 between T11 and L2, one below L2. Twenty seven patients obtained an erection of grade 4 or 5. Alprostadil was used 51 times, moxisylite nine times and papaverine four times. The average dose necessary to obtain a grade 4 or 5 functional erection adequate for coitus was 12.3 +/- 4.8 microgram with alprostadil and 14 +/- 5.4 mg with moxisylite. No side effects were noted. The nine left patients did not archive satisfying erection during this study. No clinical differences were noted in this population, compared with the 27 other patients. CONCLUSION: The findings confirm the efficiency of intracavernous injections in the management of erectile dysfunction in SCI. The average doses required to obtain a functional erection was 12.3 (+/- 4.8) microgram with alprostadil and 14 (+/- 5.4) mg with moxisylyte.     

Intraspecific 16S rRNA gene diversity among clinical isolates of Neisseria species

In the present work, nearly the entire 16S rRNA gene sequences of 46 clinical samples of Neisseria spp. were determined, and the aligned sequences were analyzed to investigate the diversity of 16S rRNA genes in each commensal Neisseria species. Two 16S rRNA types were identified in two Neisseria sicca strains, three 16S rRNA types in five Neisseria macacae strains, fourteen 16S rRNA types in twenty Neisseria flavescens isolates, and fourteen 16S rRNA types in nineteen Neisseria mucosa isolates. The number of nucleotides that were different between 16S rRNA sequences within specie ranged from 1 to 15. We found high intraspecific sequence variation in 16S rRNA genes of Neisseria spp. strains.     

A three-dimensional model of the Fas/APO-1 molecule: cross-reactivity of anti-Fas antibodies explained by structural mimicry of antigenic sites

Fas/APO-1 is a member of the tumor necrosis factor (TNF)/nerve growth factor receptor family. This cell surface protein, when associated with the Fas/APO-1 ligand or specific mAb, elicits an apoptotic response in susceptible cells via an oligomerization of its intracellular domains, termed the'death domains'. We have previously mapped the epitopes of a panel of Fas/APO-1-reactive mAb to a series of linear portions of the Fas/APO-1 molecule. In order to gain a greater understanding of the mode of interaction of these antibodies with the Fas/APO-1 antigen, we constructed a homology-based model of the extracellular portion of the molecule, based on the crystallographic coordinates of the TNF type I receptor. The model clearly demonstrates that the antibodies do not identically mimic the endogenous ligand to achieve their effect, but probably act in an analogous manner by recruiting Fas/APO-1 molecules into clusters which may lead to oligomerization of 'death domains'. Moreover, the apparent cross-reactivity observed for the monoclonal anti-Fas antibodies between different linear regions of the Fas/APO-1 molecule was found to be due, most likely, to the structural mimicry of these epitopes. Reduction of the Fas/APO-1-derived cross-reactive peptides by dithiothreitol completely abrogated their antigenic reactivity with the anti-Fas mAb CH-11, thus indicating that the establishment of intrapeptide disulfide bonds is critical for antigenic reactivity.