Detection of autoimmunity in early primary Epstein-Barr virus infection by Western blot analysis.

OBJECTIVES: The Epstein-Barr virus (EBV) represents a potentially important factor in the pathogenesis of certain autoimmune disorders such as systemic lupus erythematosus (SLE), and Sjögren's syndrome, probably through a molecular mimicry mechanism. Several studies have focused on the relationship between previous EBV infection and clinically overt connective tissue diseases (CTDs), while the aim of this study was to investigate the immunological alterations during the early phase of primary acute EBV infection by means of ENA Western blotting (WB) analysis. This technique is able to detect a wide spectrum of anti-ENA autoantibodies, potentially directed against diverse epitopes of the same antigen. METHODS: Sera from 54 subjects (F/M=24/30, mean age 17+/-6 SD years) with primary acute EBV infection were analysed using indirect immunofluorescence (IF) on Hep-2 cells for ANA, and both ELISA and WB for ENA. RESULTS: Only 8 ANA+ and no ENA+ were found by means of IF and ELISA techniques, respectively; however, one or more ENA autoantibodies were detected in 24/54 (44%) sera using WB. The autoantibodies were no longer present at the second evaluation. Subjects with immunological alterations had not developed any significant clinical manifestations at a 5-year follow-up. CONCLUSIONS: This study demonstrated the appearance of autoantibody production in a high proportion of individuals with primary acute EBV infection; interestingly, the observed serological subsets are quite similar to clinical SLE clusters. Moreover, the absence of immunological disorders during the follow-up reinforces the role of multiple genetic and/or environmental co-factors in the pathogenesis of CTDs.

Classical nonlinearity and quantum decay: the effect of classical phase-space structures.

We investigate the decay process from a time dependent potential well in the semiclassical regime. The classical dynamics is chaotic and the decay rate shows an irregular behavior as a function of the system parameters. By studying the weak-chaos regime we are able to connect the decay irregularities to the presence of nonlinear resonances in the classical phase space. A quantitative analytical prediction that accounts for the numerical results is obtained.

Immunological changes and stress are associated with different implantation rates in patients undergoing in vitro fertilization-embryo transfer.

OBJECTIVE: To evaluate the possible correlation between immunological changes and implantation rates in patients who undergo in vitro fertilization-embryo transfer (IVF-ET). DESIGN: Controlled clinical study. SETTING: University hospital. PATIENT(S): Forty infertile women undergoing IVF-ET. INTERVENTION(S): Stroop Color Word (CW) test, State-Trait Anxiety Inventory (STAI) test, blood sampling. MAIN OUTCOME MEASURE(S): Heart rate and systolic and diastolic blood pressure responses to Stroop CW; circulating T, B, T-helper (CD4), and T-suppressor (CD8) lymphocytes. RESULT(S): The total number of T lymphocytes increased significantly during superovulation, resulting in significantly higher levels in subjects achieving embryo implantation than in those showing a failure of implantation. An opposite trend was observed for the activated T cells. The number of T-helper lymphocytes and the T-helper/T-suppressor ratio showed a significant increase from baseline to the time of pick-up only in patients with implantation. CONCLUSION(S): A prolonged condition of stress, which causes a decreased ability to adapt and a transitory anxious state, is associated with high amounts of activated T cells in the peripheral blood. Such a condition, in turn, is associated with a reduced implantation rate in women undergoing IVF-ET.

Effects of chronic exposure to anaesthetic gases on some immune parameters.

A cross-sectional survey was carried out to evaluate the relation between occupational exposure to low levels of anaesthetic gases (nitrous oxide and isoflurane) and immune parameters. Fifty-one anaesthetists were recruited among different Services of Anaesthesiology and Reanimation. The control group consisted of non-exposed physicians, similar for gender, age, and job grade. Total number of lymphocytes, lymphocyte subpopulations and the natural killer (NK) cytotoxic activity were measured. Information on personal and professional characteristics and on short- and long-term exposure was collected. Percentages of T cells (CD3) decreased significantly in anaesthetists compared to controls, whereas numbers of NK cells (CD16+ CD3-) increased. After correction for confounders, short-term (last 2 weeks) exposure was associated with a decrease in percentages of total T and T helper (CD4) cells. Furthermore, T helper percentages were significantly reduced with increasing individual exposure score evaluated on the basis of working days and levels of anaesthetic gases in operating rooms. A significant X-ray-associated increase of numbers and percentages of NK cells was lastly observed. Despite limited present exposure to anaesthetic gases, a specific derangement in lymphocyte subpopulations, with T lymphocytes more affected than B, has been observed.

Towards the thermodynamics of localization processes

We study the entropy time evolution of a quantum mechanical model, which is frequently used as a prototype for Anderson's localization. Recently Latora and Baranger [Phys. Rev. Lett. 82, 520 (1999)] found that there exist three entropy regimes, a transient regime of passage from dynamics to thermodynamics, a linear-in-time regime of entropy increase, that is, a thermodynamic regime of Kolmogorov kind, and a saturation regime. We use the nonextensive entropic indicator advocated by Tsallis [J. Stat. Phys. 52, 479 (1988)] with a mobile entropic index q, and we find that the adoption of the "magic" value q=Q=1/2, compared to the traditional entropic index q=1, reduces the length of the transient regime and makes earlier the emergence of the Kolmogorov regime. We adopt a two-site model to explain these properties by means of an analytical treatment and we argue that Q=1/2 might be a typical signature of the occurrence of Anderson localization.

Relation between immune variables and burnout in a sample of physicians.

OBJECTIVES: To evaluate in a group of physicians the relation between burnout, demographic or job characteristics, anxiety, and immune variables. METHODS: Seventy one physicians of all grades were recruited among different departments to a cross sectional survey. The Maslach burnout inventory, scales of emotional exhaustion, depersonalisation, and personal accomplishment, the trait scale of anxiety inventory (STAI-Y2), and a questionnaire on personal and professional characteristics were administered. The immune profile included quantitative (number (%) of lymphocytes and subsets) and functional (natural killer cytotoxicity) measures. RESULTS: With a model of stepwise multiple regression analysis, emotional exhaustion was significantly affected by both personal (marital, sex) and job characteristics (qualification, working activity), whereas only patient contact explained a portion of variation in depersonalisation. Furthermore, trait anxiety was found to predict the Maslach burnout inventory scores. After correction for potential confounders, physicians who scored high levels of personal accomplishment showed significantly higher numbers of total lymphocytes, T cells (CD3), T helper cells (CD4), and T suppressor cells (CD8) than those who scored low levels. No other correlation was found between burnout and immune variables. CONCLUSIONS: In our group of relatively young physicians a high degree of personal accomplishment was associated with an increase in the number of peripheral lymphocytes, particularly T subsets. The meaning of this is not clear, although it could be speculated that to evaluate oneself positively, particularly with regard to work with patients in the health services, might help to stimulate the immune system. By contrast, there is no evidence that to work hard, to feel tired from work, and to have a cynical reaction towards patient care is related to immunosuppression.

Coordinate changes of polyamine metabolism regulatory proteins during the cell cycle of normal human dermal fibroblasts.

In human dermal fibroblasts, brought to quiescence (G0) by serum starvation, the S phase peaked 24 h and G2/M phases 36 h after serum re-addition. Under the same conditions, ornithine decarboxylase mRNA peaked at 12 h, decreased markedly in S phase and remained low until 48 h. Conversely, ornithine decarboxylase antizyme transcript dropped to its lowest level at 12 h, while reaching its highest values between 24 and 48 h. Ornithine decarboxylase activity followed essentially the pattern of its mRNA, but relative changes were much greater. S-Adenosylmethionine decarboxylase transcript and enzyme activity also peaked at around 12 h, decreasing thereafter. Spermidine/spermine N1-acetyltransferase mRNA and activity reached the highest values at 36-48 h. Putrescine concentration increased up to 18 h and fell dramatically in the S phase, remaining low thereafter. Both spermidine and spermine reached peaks at 18 h and decreased in the S phase, but not nearly as much as putrescine. We discuss how this comprehensive study may help to understand the involvement of polyamines in the control of cell proliferation.

Phenotypic characteristics and tendency to apoptosis of peripheral blood mononuclear cells from HIV+ long term non progressors.

The aim of this study was to analyze (i) phenotype, (ii) in vitro spontaneous and induced apoptosis, (iii) glutathione (GSH) intracellular content and (iv) inhibitors of apoptosis of potential therapeutical use in peripheral blood mononuclear cells (PBMC) from HIV+ long term non progressors (LTNP), in comparison with progressors (HIV+P) and seronegative controls (HIV-). Three groups of subjects were studied: 15 HIV+P (patients losing >150 CD4+/year), 9 LTNP (subjects infected by HIV for at least 7 years without clinical and immunological signs of progression, with a mean of 898 CD4+/microL) and 18 HIV-. All subjects were living in a large community for former drug addicts, and were matched for age and sex. We used flow cytometry for analyzing PBMC phenotype and apoptosis; high performance liquid chromatography for measuring intracellular GSH content. PBMC phenotype of LTNP shared characteristics with those of both HIV- and HIV+P. Indeed, LTNP showed a normal number CD4+ cells (an inclusion criteria), but significantly increased numbers of CD8+ lymphocytes, activated T cells, CD19+, CD5+ B lymphocytes and CD57+ cells, as well as a decrease in CD19+, CD5- B lymphocytes and CD16+ cells. In LTNP, spontaneous apoptosis was similar to that of HIV- and significantly lower than that of HIV+P. Adding interleukin-2 (IL-2) or nicotinamide (NAM) significantly decreased spontaneous apoptosis in LTNP and HIV+P. Pokeweed mitogen-induced apoptosis was also similar in LTNP and HIV-, but significantly lower than that of HIV+P. In HIV+P, but also in LTNP, spontaneous apoptosis was inversely correlated to the absolute number and percentage of CD4+ cells and directly correlated to the number and percentage of activated T cells present in peripheral blood. GSH intracellular content was greatly decreased in PBMC from HIV+P and slightly, but significantly, reduced in LTNP. Adding 2-deoxy-D-ribose, an agent provoking apoptosis through GSH depletion, to quiescent PBMC resulted in similar levels of massive cell death in the three groups. This phenomenon was equally prevented in the three groups by N-acetyl-cysteine but not by IL-2. A complex immunological situation seems to occur in LTNP. Indeed, PBMC from LTNP are characterized by a normal in vitro tendency to undergo apoptosis despite the presence of a strong activation of their immune system, unexpectedly similar to that of HIV+P. Our data suggest that NAM and IL-2 are possible candidates for reducing spontaneous apoptosis in HIV infection.

Fractal properties of ion channels and diffusion.

We focus our attention on a fractal model recently proposed by Liebovitch to account for the lack of a time scale in ion channel kinetics. We establish a connection between the dwell-time distributions and the correlation time of the ion channel signal, thereby making it possible to derive analytical predictions on the diffusion properties of a random walk constructed from the sum of the current fluctuations of ion channels. With the help of a numerical simulation of the Liebovitch model, it is shown that the Hurst analysis can provide a reliable determination of the standard (or anomalous) diffusion properties. On the basis of results of computer simulation we argue that by applying the Hurst analysis to the experimental distribution of closed times it is possible, in principle, to establish whether the Liebovitch model is valid.