The effect of antituberculosis treatment on interferon-gamma release assay results.

BACKGROUND AND AIM: Monitoring the efficacy of antituberculosis therapy is crucial. The aim of this work is to investigate the effect of tuberculosis treatment on interferon-gamma response using Quanti-FERON-TB Gold in tube (QFT-GIT). METHODS: A total of 216 new pulmonary tuberculosis (TB) cases were tested with QFT-GIT at the start of the treatment and, randomly, once or twice between 90 and 180 days afterwards. Data was analysed using the random effect regression model analysis. RESULTS: 63.4% of patients were positive at the QFT-GIT (> .35 UI cut-off). TB cases showed a significant log-linear increase in interferon-gamma (IFN-gamma) concentration, over time of treatment: IFN-gamma concentration increased by 78% after 6 months of treatment in acid-fast bacilli positive (A) and culture negative cases in culture confirmed cases the increase was 43% if A+ and 20% in A-. CONCLUSIONS: Effective therapy seems to restore cellular responses to Mycobacterium tuberculosis antigens. The potential use of interferon gamma release assay (IGRA) in monitoring response to TB treatment is hampered by the presence of active mycobacterial replication at baseline and needs further evaluation.

Evaluation of oxidative stress in rheumatoid and psoriatic arthritis and psoriasis.

INTRODUCTION: The aim of the present study is to discuss the importance of the processes of oxidative stress in the pathogenesis of certain autoimmune diseases, to search for an appropriate assessment marker, and to debate current approaches which have been proposed for the treatment of Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA), and Psoriasis (Ps). MATERIALS AND METHODS: The total antioxidant capacity (TAC), the thiolic capacity (TC), and the serum hydroperoxide concentration (SHC) were measured in 37 subjects: 13 with RA, 8 with PsA, 8 with Ps, and 8 healthy controls. RESULTS: SHC levels were significantly higher in patients with RA (p = 0.01), as well as in those with PsA (p = 0.005) and Ps (p = 0.002) in comparison with the control group. However, a significant reduction in the TAC values in the serum of all three groups (RA, p = 0.03; PsA, p = 0.005; Ps, p = 0.001) were observed in comparison with the healthy controls. The thiolic concentration were found to have significantly diminished in patients with RA (p =0.0005) and Ps (p = 0.0005) in comparison with the control group. Our findings have brought out the fact that the therapeutic treatment of RA using biological drugs is more than satisfactory in accord with the considerable increase in the TAC values, although not significantly, compared to those patients treated with DMARDs. CONCLUSIONS: The determination of the parameters of oxidative stress utilising these methods may be useful as a quick test, and as routine in monitoring the state of oxidative stress in patients suffering from RA, PsA, and Ps, so that a more effective treatment for ROS can be undertaken accordingly. The administration of biological drugs seems to have a role in increasing the mechanism of the barrier which the body possesses against oxidative stress.

Moxifloxacin for the treatment of HIV-associated tuberculosis in patients with contraindications or intolerance to rifamycins.

Administration of rifampicin or rifabutin in the treatment of HIV-associated tuberculosis (TB) is made rather complex by the risk of drug-drug interactions with most antiretrovirals and/or for reasons of toxicity. While in selecting the appropriate concomitant regimens the priority usually goes to rifamycins with exclusion of interacting antiretrovirals, in some circumstances the former cannot be used and anti-TB rifamycin-free regimens must be administered. We describe here the clinical course of two patients with HIV-associated TB in whom the last generation fluorquinolone moxifloxacin (found to exert significant activity against Mycobacterium tuberculosis) successfully replaced rifamycins.

Expression of an altered ribonucleotide reductase activity associated with the replication of murine cytomegalovirus in quiescent fibroblasts.

Ribonucleotide reductase (RNR) is an essential enzyme for the de novo synthesis of both cellular and viral DNA and catalyzes the conversion of ribonucleoside diphosphates into the corresponding deoxyribonucleoside diphosphates. The enzyme consists of two nonidentical subunits, termed R1 and R2, whose expression is very low in resting cells and maximal in S-phase cells. Here we show that murine cytomegalovirus (MCMV) replication depends on ribonucleotide reduction since it is prevented by the RNR inhibitor hydroxyurea. MCMV infection of quiescent fibroblasts markedly induces both mRNA and protein corresponding to the cellular R2 subunit, whereas expression of the cellular R1 subunit does not appear to be up-regulated. The increase in R2 gene expression is due to an increase in gene transcription, since the activity of a reporter gene driven by the mouse R2 promoter is induced following virus infection. Cotransfection experiments revealed that expression of the viral immediate-early 1 protein was sufficient to mediate the increase in R2 promoter activity. It was found that the viral gene M45, encoding a putative homologue of the R1 subunit, is expressed 24 and 48 h after infection. Meanwhile, we observed an expansion of the deoxyribonucleoside triphosphate pool between 24 and 48 h after infection; however, neither CDP reduction nor viral replication was inhibited by treatment with 10 mM thymidine. These findings indicate the induction of an RNR activity with an altered allosteric regulation compared to the mouse RNR following MCMV infection and suggest that the virus R1 homologue may complex with the induced cellular R2 protein to reconstitute a new RNR activity.

The thymidylate synthase inhibitor ZD1694 potently inhibits murine and human cytomegalovirus replication in quiescent fibroblasts.

Tomudex (ZD1694) is a quinazoline-based folate analog and a powerful inhibitor of cellular thymidylate synthase and is approved in Europe for use in oncology. Here the first evidence of its activity against murine and human cytomegalovirus (MCMV and HCMV) is reported. ZD1694 irreversibly inhibited the replication and DNA synthesis of both viruses in quiescent fibroblasts. The corresponding 50% effective concentrations were 0.006 and 0.002 microM respectively, whereas the 50% cytotoxic concentration was >10 microM for both murine and human quiescent fibroblasts. A similar antiviral effect was observed against two ganciclovir-resistant HCMV strains isolated from AIDS patients. Taken as a whole these results demonstrate that cellular thymidylate synthase plays an essential role in viral replication and that ZD1694 merits further investigation as anticytomegaloviral agent.

Overexpression of cellular dihydrofolate reductase abolishes the anticytomegaloviral activity of methotrexate.

Cytomegalovirus (CMV) stimulates numerous cellular pathways upon infection. One of these pathways involves activation of dihydrofolate reductase (DHFR), an essential enzyme in the biosynthesis of purines and thymidylate. Here we report that methotrexate (MTX), an inhibitor of DHFR, suppresses murine CMV replication at the level of DNA synthesis in quiescent NIH 3T3 cells. However, MTX has no antiviral activity in NIH 3T3 sublines resistant to MTX due to DHFR overexpression. These results directly link MTX antiviral activity to DHFR and demonstrate that DHFR plays an essential role for CMV replication in quiescent cells.

[Recurrent post-traumatic osteitis of the leg: Patent Blue V® dye, Gentamicin-PMMA-Beads and double muscular flap]. / Ostéite de jambe post-traumatique récidivante : coloration au Bleu Patenté V®, billes de ciment à la gentamicine et double lambeau musculaire.

The authors describe the case of a 31-year old man who had a recurrent post-traumatic osteitis of the left leg with two fistulae for more than one year. Many unsuccessful proceedures were tried: removal of the tibial nail with reaming and filling with Gentamicin-PMMA-beads, fascio-cutaneous flap and open cancellous bone graft. They emphasize the bacteriological and imaging examinations particularly MRI. They recommend high-pressure oxygen therapy for a few days before operation in the case of chronic infected tissues, the use of Patent Blue V® dye to display bone sequestra prominently, filling with Gentamicin-PMMA-beads, an effective cover, in this case, with an original double muscular flap and long-term antibiotics. The rapid normalization of the CRP (C Reactive Protein) is a good sign of healing and the authors think that MRI allows early detection of recurrence of infection and shows the good perfusion of the muscular flap.