DNA repair systems and the pathogenesis of Mycobacterium tuberculosis: varying activities at different stages of infection

Mycobacteria, including most of all MTB (Mycobacterium tuberculosis), cause pathogenic infections in humans and, during the infectious process, are exposed to a range of environmental insults, including the host's immune response. From the moment MTB is exhaled by infected individuals, through an active and latent phase in the body of the new host, until the time they reach the reactivation stage, MTB is exposed to many types of DNA-damaging agents. Like all cellular organisms, MTB has efficient DNA repair systems, and these are believed to play essential roles in mycobacterial pathogenesis. As different stages of infection have great variation in the conditions in which mycobacteria reside, it is possible that different repair systems are essential for progression to specific phases of infection. MTB possesses homologues of DNA repair systems that are found widely in other species of bacteria, such as nucleotide excision repair, base excision repair and repair by homologous recombination. MTB also possesses a system for non-homologous end-joining of DNA breaks, which appears to be widespread in prokaryotes, although its presence is sporadic within different species within a genus. However, MTB does not possess homologues of the typical mismatch repair system that is found in most bacteria. Recent studies have demonstrated that DNA repair genes are expressed differentially at each stage of infection. In the present review, we focus on different DNA repair systems from mycobacteria and identify questions that remain in our understanding of how these systems have an impact upon the infection processes of these important pathogens

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Not AvailableThe Western Ghats region of Indian subcontinent is one of the main biodiversity hot spots in the world. This region is very rich in diverse edible fruit yielding plant species. The latitudinal position, topography, wide rainfall variation and varied temperature conditions enable inhabitancy of several plant species. The plant diversity of the region may be groups in two categories, the native species and the exotic species naturalized in the region. There are more than 50 native edible fruit species are available in the region. The important species are Garcinia gummigutta, Garcinia morela, Garcinia xanthochymus, Artocarpus heterophyllus Artocarpus hirsutus, Artocarpus laccocha, Carissa carandas, Emblica officinalis, Phyllanthus acidus, Syzygium cuminii , Chrysophyllum roxburghii, Canthium parviflora, Elaeagnus conferta , Elaeagnus latifolia , Securina leucopyrus , Elaeocarpus tuberculatus, Nephelium stipulacum syn.Doratoxylon stipulatum, Flacourtia indica, Flacourtia Montana, Baccouria courtalensis and minor Citrus spp . The majority of these fruits belong to families Apocynaceae, Anacardiaceae. Euphorbiaceae, Moraceae, Sapotaceae,Legominosae and Sapindaceae. The noteworthy exotic naturalized species are Nephelium lappaceum var.lappaceum, Persia americana , Dimocarpus longan , Annona muricata, Citrus reticulata, Litchi chinensis, Garcinia mangotana, Artocarpus altilis , Syzygium sumarangense, Syzygium roseum, Syzygium aqueum , Averhoa carambola, Averhoa bilimbi etc. There is lot of variability in the growth habit, fruiting pattern, yield fruit shape, colour and quality among different collections of these fruits. Some of these fruits were collected and characterized and planted for conservation and utilization in futureNot Availabl

Bruk av kvetiapin mot insomni i primærhelsetjenesten. Kvalitetsforbedringsprosjekt

Denne oppgaven er et forslag til et kvalitetsforbedringsprosjekt hvor målet er redusert forskrivning av kvetiapin, utenfor indikasjon, mot insomni i primærhelsetjenesten. Årsaken til at allmennlegetjenesten er valgt som det primære målet for dette kvalitetsforbedringsprosjektet, er fordi pasienter med insomni henvender seg først og fremst til allmennleger. For allmennleger kan i de fleste tilfeller selv starte opp en behandling i henhold til godkjente og anbefalte indikasjoner og retningslinjer. Undersøkelse av dagens praksis viser at det er nettopp i dette leddet at behandlingen av insomni svikter med tanke på forskrivning av kvetiapin mot insomni. Dette samsvarer med gruppedeltakernes erfaringer fra praksistiden og jobb. Derfor vil det i denne oppgaven redegjøres for hvilke tiltak som kan settes i verk i primærhelsetjenesten for å redusere forskrivningen av kvetiapin mot insomni, og dermed bedre kvaliteten av tilbudet for insomni med størst mulig gevinst for pasientene som insentiv

Pathogenicity of Moraxella osloensis, a Bacterium Associated with the Nematode Phasmarhabditis hermaphrodita, to the Slug Deroceras reticulatum

Moraxella osloensis, a gram-negative bacterium, is associated with Phasmarhabditis hermaphrodita, a nematode parasite of slugs. This bacterium-feeding nematode has potential for the biological control of slugs, especially the grey garden slug, Deroceras reticulatum. Infective juveniles of P. hermaphrodita invade the shell cavity of the slug, develop into self-fertilizing hermaphrodites, and produce progeny, resulting in host death. However, the role of the associated bacterium in the pathogenicity of the nematode to the slug is unknown. We discovered that M. osloensis alone is pathogenic to D. reticulatum after injection into the shell cavity or hemocoel of the slug. The bacteria from 60-h cultures were more pathogenic than the bacteria from 40-h cultures, as indicated by the higher and more rapid mortality of the slugs injected with the former. Coinjection of penicillin and streptomycin with the 60-h bacterial culture reduced its pathogenicity to the slug. Further work suggested that the reduction and loss of pathogenicity of the aged infective juveniles of P. hermaphrodita to D. reticulatum result from the loss of M. osloensis from the aged nematodes. Also, axenic J1/J2 nematodes were nonpathogenic after injection into the shell cavity. Therefore, we conclude that the bacterium is the sole killing agent of D. reticulatum in the nematode-bacterium complex and that P. hermaphrodita acts only as a vector to transport the bacterium into the shell cavity of the slug. The identification of the toxic metabolites produced by M. osloensis is being pursued