Suppression of the immune response by Shigella in experimental influenza infection in mice

Experiments in mice have demonstrated that in the presence of influenza infection the suppressing effect of virulent shigellae on the secondary humoral and cell-mediated immune response is enhanced. Under such conditions avirulent shigellae can also show suppressing effect which is usually absent in these organisms.     

Screening method for microorganisms producing L-aminoacids from D,L-5-monosubstituted hydantoins

Summary The ability of microorganisms to produce hydantoinase and L-N-carbamoylase could be established by an overlay assay. Enzyme producing strains form clear areas around their colonies caused by the cleavage of D,L-indolylmethylhydantoin. A second overlayer with a tryptophan-auxotroph yeast enables us to detect microorganisms which are able to produce L-tryptophan from D,L-indolylmethylhydantoin.     

Rural health care looks to the future. Issues in the institutionalization and management of rural health care: making technology appropriate

Experimental projects have demonstrated the technical feasibility of systems of accessible, affordable health care. These projects have relied extensively on non-professional community health workers. However, large-scale implementation of these schemes will require new management procedures that are both responsive to rural health needs and congruent with national institutions. This paper identifies the need to establish institutional mechanisms to mobilize essential inputs, promote acceptance by beneficiaries, maintain quality standards, recruit and retain field staff, and achieve accountability for resources. It then outlines methods for developing these institutions. It stresses the need for both formal, bureaucratic organizations and informal organizations of clients. It also identifies the need to consider administrative and institutional resources in determining the appropriateness of a health care technology.     

A Toxoplasma type 2C serine-threonine phosphatase is involved in parasite growth in the mammalian host cell

Toxoplasma gondii is a human protozoan parasite that belongs to the phylum of Apicomplexa and causes toxoplasmosis. As the other members of this phylum, T. gondii obligatory multiplies within a host cell by a peculiar type of mitosis that leads to daughter cell assembly within a mother cell. Although parasite growth and virulence have been linked for years, few molecules controlling mitosis have been yet identified and they include a couple of kinases but not the counteracting phosphatases. Here, we report that in contrast to other animal cells, type 2C is by far the major type of serine threonine phosphatase activity both in extracellular and in intracellular dividing parasites. Using wild type and transgenic parasites, we characterized the 37 kDa TgPP2C molecule as an abundant cytoplasmic and nuclear enzyme with activity being under tight regulation. In addition, we showed that the increase in TgPP2C activity significantly affected parasite growth by impairing cytokinesis while nuclear division still occurred. This study supports for the first time that type 2C protein phosphatase is an important regulator of cell growth in T. gondii.