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Urate crystal size change and the modification of coated proteins by oxygen radicals released by stimulated polymorphonuclear cells (PMN) could represent a likely "switch-off" mechanism of the spontaneous resolution of acute gout attack. The absorption spectra and the uric acid, allantoin and urea concentrations were determined before and after in vitro exposition of monosodium urate (MSU) crystals to superoxide anion (O2) photochemically generated. The results showed a complete dissolution of MSU crystals after incubation under O2-, with decrease of uric acid and increase of allantoin and urea concentrations. Our results were confirmed by polarizing, electron microscopy and calorimetric techniques. The results obtained seem to confirm that the spontaneous resolution of acute gout attack could be attributed to the dissolving effect on urate crystals and the modification of coated proteins by O2- released by phagocytizing PMN.

Urate crystal size change and the modification of coated proteins by oxygen radicals released by stimulated polymorphonuclear cells (PMN) could represent a likely "switch-off" mechanism of the spontaneous resolution of acute gout attack. The absorption spectra and the uric acid, allantoin and urea concentrations were determined before and after in vitro exposition of monosodium urate (MSU) crystals to superoxide anion (O2) photochemically generated. The results showed a complete dissolution of MSU crystals after incubation under O2-, with decrease of uric acid and increase of allantoin and urea concentrations. Our results were confirmed by polarizing, electron microscopy and calorimetric techniques. The results obtained seem to confirm that the spontaneous resolution of acute gout attack could be attributed to the dissolving effect on urate crystals and the modification of coated proteins by O2- released by phagocytizing PMN.

Although the literature recognises the involvement of neuropeptide structures in the genesis of epilepsy, only tentative preliminary data are available at present. Experiments indicate that neuropeptides primarily involved in the genesis of epilepsy are leuencephalin, metencephalin and beta-endorphin. Their convulsion properties are apparently related to the specific levels, locations and convulsive potential of the individual substances. A qualitative and/or quantitative change to the GABA-neuropeptide balance may also be involved in convulsive disorders; decreased GABA fluid levels have been identified in both severely epileptic patients and infants with febrile convulsions. Neuropeptide modulation and GABAergic neurotransmission clearly therefore play a major role in the regulation of cortical bioelectrical activity. It is therefore likely that their interaction is involved in the genesis of epilepsy.

A descriptive epidemiological survey conducted in Turin on a population of 1,065,304 in Jan. 1-June 30 1984, produced preliminary data on the incidence of MS. Given the restricted area and brief duration of the survey, such data are however purely indicative. Primarily clinical criteria supported by instrumental and laboratory tests (P., Ev., liquor) were uniformly adopted.

The biological role of the murine IFN-gamma endogenously secreted during cell activation has been probed by the use of a rat mAb (AN18) that specifically neutralizes its activity. When An18 mAb is added to the cultures of BALB/c and C57BL/6 nylon nonadherent spleen cells (naSpc) stimulated for 18 h with 1000 U of IL-2, the normally released IFN-gamma can no longer be detected in the supernatants and the IL-2-induced proliferative response is markedly reduced as compared with control cultures set up in the presence of an unrelated rat mAb. By contrast, the increased natural cytotoxicity is not affected. The 96-h culture of both BALB/c and C57BL/6 naSpc in the presence of 1000 U of IL-2 resulted in marked lymphocyte proliferation and generation of lymphokine-activated killer activity. The presence of An18 mAb strongly inhibited both functions. Similarly, when naSpc were stimulated with mitomycin C-inactivated allogeneic leukocytes in the presence of An18 mAb, the normal proliferative response and specific cytotoxicity were almost abolished, whereas the secretion of IL-2 was in no way affected. Lymphocytes recovered from 3-day cultures stimulated by IL-2 or allogeneic cells in the presence of An18 mAb displayed a decrease of the expression of the p55 chain of IL-2R, as shown by flow cytofluorimetry. Moreover, binding experiments with 125I-labeled IL-2 showed that lymphocytes from allostimulated cultures set up in the presence of An18 mAb display a decreased number of low affinity and almost no high affinity IL-2R as compared with control cultures. These data show that endogenous IFN-gamma plays an obligatory role for the de novo induction of cytolytic activity in lymphokine-activated killer cells and CTL, most probably by affecting the membrane expression of high affinity IL-2R.

The effects of interferon (IFN gamma) and of IFN alpha/beta on normal T and B lymphocytes and various T and non-T human and murine cell lines have been investigated. IFN gamma, unlike IFN alpha/beta, did not promote the antiviral state in T cells. The lack of antiviral activity was confirmed at the biochemical level by the finding that 2',5' oligoadenylate synthetase activity is not induced in T cells by IFN gamma only.

Results are reported concerning the extraction and purification of gangliosides present in CER cells, a cell line which is highly suitable for the cultivation in vitro of rabies virus. By means of thin layer chromatography it has been possible to demonstrate that the CER cell ganglioside pattern is composed mainly of monosialo and disialogangliosides.

Post-transplant lymphoproliferative disorders (PTLD), ranging from lymphoid hyperplasia to clonal malignancy, are a severe complication arising in solid organ transplant patients. Their reported incidence ranges from 1 to 20%, according to factors such as type of transplanted organ and the age of recipients. A strong correlation between Epstein Barr virus (EBV) infection, the grade and type of immunosuppression and the development of PTLD has been recognized. The detection and quantification of EBV-DNA load in peripheral blood have been utilized as prognostic markers for the development of PTLD, showing a correlation between high levels of EBV-DNA in the blood and the development of PTLD. In this study, we monitored EBV viral load monthly in 15 renal transplant recipients for six months. The number of EBV-DNA copies was measured in peripheral blood mononuclear cells (PBMC) and serum samples by a quantitative PCR protocol developed in our laboratory that employes a previous screening of samples containing a significant number of viral DNA copies (or =1000 copies/10(5) PBMC or 100 microl serum) by semi-quantitative PCR followed by a precise quantification of the only significant samples by quantitative-competitive (QC)-PCR. Our 15 renal transplant patients neither developed PTLD nor had recurrent acute illnesses or acute graft rejections during the study. The results obtained in the monthly follow up of EB viral load in PBMC samples confirmed its fluctuation in asymptomatic patients reported in literature. In particular, 5/14 (35.7%) of EBV seropositive patients had an EBV-DNA load equal to 1000 EBV copies /10(5) PBMC (roughly corresponding to 10.000 copies/microg PBMC DNA), and 1/14 (7.1%) reached 5000 EBV copies /10(5) PBMC (roughly corresponding to 50.000 copies/microg PBMC DNA), at least once in our study. In the EBV seronegative patient, EBV-DNA in PBMC samples was always undetectable (less than 100 DNA copies/10(5) PBMC). EBV-DNA load in all serum samples was less than threshold value of our quantification protocol (100 DNA copies/100 microl serum), supporting the literature data. With regard to immunosuppressive treatment, 66.7% of the six patients in whom EBV load reached values equal to or higher than 1000 DNA copies/10(5) PBMC, were on FK506 whereas only 33.3% of them were on CyA. In conclusion, further investigations are needed to better understand the role of EBV infection in the pathogenesis of PTLD in immunosuppressed patients. Given the high positive predictive value of EB viral load in peripheral blood for diagnosis of PTLD reported by several authors, and the described absence of correlation between the serological evidence of EBV reactivation and EB viral load, EBV viral load measurement in PBMC and serum samples using quantitative PCR techniques is a powerful diagnostic tool to monitor transplanted patients at risk to develop PTLD.