Nonsusceptibility of Primate Cells to Taura Syndrome Virus

Primate cells commonly used to test for viruses of the Picornaviridae family are not susceptible to infection by Taura syndrome virus of penaeid shrimp

The responses of an anaerobic microorganism, Yersinia intermedia MASE-LG-1 to individual and combined simulated Martian stresses

The limits of life of aerobic microorganisms are well understood, but the responses of anaerobic microorganisms to individual and combined extreme stressors are less well known. Motivated by an interest in understanding the survivability of anaerobic microorganisms under Martian conditions, we investigated the responses of a new isolate, Yersinia intermedia MASE-LG-1 to individual and combined stresses associated with the Martian surface. This organism belongs to an adaptable and persistent genus of anaerobic microorganisms found in many environments worldwide. The effects of desiccation, low pressure, ionizing radiation, varying temperature, osmotic pressure, and oxidizing chemical compounds were investigated. The strain showed a high tolerance to desiccation, with a decline of survivability by four orders of magnitude during a storage time of 85 days. Exposure to X-rays resulted in dose-dependent inactivation for exposure up to 600 Gy while applied doses above 750 Gy led to complete inactivation. The effects of the combination of desiccation and irradiation were additive and the survivability was influenced by the order in which they were imposed. Ionizing irradiation and subsequent desiccation was more deleterious than vice versa. By contrast, the presence of perchlorates was not found to significantly affect the survival of the Yersinia strain after ionizing radiation. These data show that the organism has the capacity to survive and grow in physical and chemical stresses, imposed individually or in combination that are associated with Martian environment. Eventually it lost its viability showing that many of the most adaptable anaerobic organisms on Earth would be killed on Mars today

Contrôle de l'eau dans les petites agglomérations : des modalités à réviser ?

L'eau de 30 communes rurales ne disposant pas de traitement de désinfection a été analysée pendant 18 semaines. Il est montré une très grande variabilité de la qualité de l'eau d'une semaine à l'autre. Une filtration de 300 ml a été menée en parallèle à celle de 100 ml. Les résultats des deux analyses sont proches lorsque l'eau est habituellement conforme sur 100 ml. Ils sont très différents lorsque l'eau est de qualité variable sur 100 ml. Les indicateurs bactériens (numération totale, coliformes totaux et fécaux, streptocoques et spores de bactéries anaérobies) présentent des résultats concordants et donc redondants. Lorsque l'eau est de qualité variable, la fréquence analyses bactériologiques par an n'est pas suffisante pour garantir la qualité Dans ce cas recommencer l'analyse après un résultat contaminé n'apporte pas d'information supplémentaire. L'amélioration de la ressource est alors prioritaire

Atypical presentation of adult T-cell leukaemia/lymphoma due to HTLV-1: prurigo nodularis lasting twelve years followed by an acute micropapular eruption.

International audiencePrurigo nodularis is a pruritic dermatosis of unknown origin. Human T-cell lymphotropic virus type 1 (HTLV-1) causes adult T-cell leukaemia/lymphoma. HTLV-1 is not considered to be a cause of prurigo nodularis. A 52-year-old black man, from the French West Indies, who had had prurigo nodularis for 12 years, presented with a distinct micropapular eruption with the typical pathological picture of epidermotropic T-cell lymphoma. Based on HTLV-1-positive serology and monoclonal integration of HTLV-1 we diagnosed smouldering adult T-cell leukaemia/lymphoma. Re-examination of previous skin biopsies revealed that the disease had been evolving for 12 years. Treatment with alpha-interferon, 3 x 106 units three times a week, associated with zidovudine, 1 g daily, resulted in complete remission within 4 months. When investigating a prurigo nodularis, we therefore recommend: (i) performing HTLV-1 serology if the patient comes from an endemic area; (ii) if positive, performing CD25 staining and looking for a HTLV-1 clonal integration; and (iii) if positive, using a treatment targeting HTLV-1