A Protein Critical for a Theiler’s Virus-Induced Immune System-Mediated Demyelinating Disease Has a Cell Type-Specific Antiapoptotic Effect and a Key Role in Virus Persistence

TO subgroup strains of Theiler’s murine encephalomyelitis virus (TMEV) induce a persistent central nervous system infection and demyelinating disease in mice. This disease serves as an experimental model of multiple sclerosis (MS) because the two diseases have similar inflammatory white matter pathologies and because the immune system appears to mediate demyelination in both processes. We previously reported (H. H. Chen, W. P. Wong, L. Zhang, P. L. Ward, and R. P. Roos, Nat. Med. 1:927–931, 1995) that TO subgroup strains use an alternative initiation codon (in addition to the AUG used to synthesize the picornavirus polyprotein from one long open reading frame) to translate L*, a novel protein that is out of frame with the polyprotein and which plays a key role in the demyelinating disease. We now demonstrate that L* has antiapoptotic activity in macrophage cells and is critical for virus persistence. The antiapoptotic action of L* as well as the differential translation of L* and virion capsid proteins may foster virus persistence in macrophages and interfere with virus clearance. The regulation of apoptotic activity in inflammatory cells may be important in the pathogenesis of TMEV-induced demyelinating disease as well as MS.     

Biochemical properties of lipoxygenase from opium poppy chloroplasts

Lipoxygenase (LOX) from opium poppy (Papaver somniferum L.) chloroplasts was isolated and 126.1-fold purified to electrophoretic homogeneity by combination of ion-exchange chromatography on HA-Ultragel column and affinity chromatography on a linoleyl-aminopropyl agarose column. The relative molecular mass of the LOX determined by SDS-PAGE was 92 kDa. Kinetic properties of purified LOX were determined in spectrophotometric assay by using of linoleic acid (K_M = 1.78 mM and V_max = 11.4 μmol mg⁻¹ min⁻¹) and linolenic acid (K_M = 1.27 mM and V_max = 10.2 μmol mg⁻¹ min⁻¹). The optimum pH was 6.0 for both linoleic and linolenic acid dioxygenation catalyzed by LOX. HPLC analysis of the products revealed a dual positional specificity of linoleic acid dioxygenation at pH 6.0 with ratio of 9- and 13-hydroperoxide products being about 1:1. The activity of purified LOX was stimulated by Mg²⁺ and Ca²⁺.     

Waste treatment in product specific life cycle inventories

The final disposal of waste in sanitary landfills generates environmental impacts in the form of gaseous emissions and effluents in the seepage water. In product specific Life Cycle Assessments, these environmental impacts resulting from the disposal of the product under study frequently have a strong influence on the overall results. The Sanitary Landfill (SL), like the Municipal Solid Waste Incineration (MSWI), is a complex system with a large variety of different types of waste with varying input composition. A direct determination of the environmental impacts resulting from the landfilling of a single input component, e.g. by measurements, is not possible. The model approach described in this paper shows an operationalized concept for the allocation of the environmental effects caused by the landfill process to special input components. The calculation of the landfill emissions in the model is based on the emission spectrum (landfill gas and seepage water) of an average-sized landfill in Germany and the elementary composition of the single waste fraction under consideration. The resulting reactor landfill module comprises an average split for diffuse and captured landfill emissions, the use of captured landfill gases in a gas engine and a cleaning of captured seepage water in a waste water treatment plant. A short case study demonstrates the calculation of the effects of landfilling of a defined waste fraction (bottle fraction in post-consumer plastic waste).     

The rice foot rot pathogen Dickeya zeae alters the in-field plant microbiome

Studies on bacterial plant diseases have thus far been focused on the single bacterial species causing the disease, with very little attention given to the many other microorganisms present in the microbiome. This study intends to use pathobiome analysis of the rice foot rot disease, caused by Dickeya zeae, as a case study to investigate the effects of this bacterial pathogen to the total resident microbiome and to highlight possible interactions between the pathogen and the members of the community involved in the disease process. The microbiome of asymptomatic and the pathobiome of foot-rot symptomatic field-grown rice plants over two growing periods and belonging to two rice cultivars were determined via 16S rRNA gene amplicon sequencing. Results showed that the presence of D. zeae is associated with an alteration of the resident bacterial community in terms of species composition, abundance and richness, leading to the formation of microbial consortia linked to the disease state. Several bacterial species were significantly co-presented with the pathogen in the two growing periods suggesting that they could be involved in the disease process. Besides, culture-dependent isolation and in planta inoculation studies of a bacterial member of the pathobiome, identified as positive correlated with the pathogen in our in silico analysis, indicated that it benefits from the presence of D. zeae. A similar microbiome/pathobiome experiment was also performed in a symptomatically different rice disease evidencing that not all plant diseases have the same consequence/relationship with the plant microbiome. This study moves away from a pathogen-focused stance and goes towards a more ecological perception considering the effect of the entire microbial community which could be involved in the pathogenesis, persistence, transmission and evolution of plant pathogens.     

La radioprotection des patients en médecine nucléaire : état des lieux en Tunisie

Recent health indicators for Tunisia are encouraging: there is one doctor for every 1000 inhabitants, in contrast to 1471 in 1996; life expectancy at birth is 73.8 years compared with 71.6 years in 1996; and the infant mortality rate is down from 29.7 per thousand in 1996 to 19.5 per thousand. The health infrastructure in Tunisia is partly private and partly public, supported by a well-organized network of university hospitals and clinics and a central pharmaceutical service that imports and distributes drugs. In 1990, there was only one nuclear medicine centre in Tunisia at the Salah Azaiez Institute. In 2013, there are 12 centres, between public and private, with around forty doctors and 50 technicians using 15 gamma cameras, seven single-head, four dual-head and three SPECT/CT. Positron emission tomography (PET) will be acquired in short delay. Training for doctors and technicians in quality control for this new equipment and quality assurance in multimodal molecular imaging will soon become a priority. The protection of patients against radiation remains a major concern for these Departments. The regulatory and institutional framework has been established since 1980. Because of their oldness, they may not be suitable for radiation protection of persons exposed for medical purposes. An assessment of the practice of nuclear medicine can be helpful to standardize used protocols and to optimize the dose delivered to the patients during different nuclear medicine procedures in vivo.