Rodents as vehicle for delivery of transgenic bacteria to make paratransgenic sand fly vectors of cutaneous leishmaniasis in field condition.

Vector-borne diseases, among them leishmaniasis, cause more than 700,000 deaths annually. The lack of an effective vaccination and the increasing resistance of sand flies to insecticides require the urgent development of innovative approaches to contain the disease. The use of engineered bacteria that express anti-parasite molecules (paratransgenesis) shows much promise. However, a challenge for implementation of this strategy is to devise means to introduce modified bacteria into sand flies in the field. In this study, we use rodent food bait as a delivery strategy to introduce two mCherry-fluorescent bacteria, Serratia AS1 and Enterobacter cloacae, into adult sand flies in field settings. Bacteria-infected food was provided to Rhombomys opimus rodents. These bacteria transiently pass through the rodent alimentary tract and are delivered to larval habitats with the rodent feces. The feces are ingested by sand fly larvae and, in the case of Serratia AS1, are trans-stadially transmitted to adults. This is the first report of targeting delivery of Serratia AS1 in a paratransgenic system to control transmission of leishmaniasis under field condition. This novel strategy shows promise for delivering transgenic bacteria to Leishmania vectors in the field.

Misfit-induced changes of lattice parameters in two-phase systems: coherent/incoherent precipitates in a matrix.

Elastic accommodation of precipitation-induced or thermally induced misfit leads to lattice-parameter changes in crystalline multi-phase systems. Formulae for calculation of such misfit-induced lattice-parameter changes are presented for the aggregate (matrix + second-phase particles) and for the individual matrix and second phase, recognizing the occurrence of either coherent or incoherent diffraction by the matrix and second-phase particles. An overview and an (re)interpretation on the above basis is presented of published lattice-parameter data, obtained by X-ray diffraction analyses of aggregates of matrix plus second-phase particles. Examples for three types of systems consisting of a matrix with misfitting second-phase particles are dealt with, which differ in the origin of the misfit (precipitation or thermally induced) and in the type of diffraction (coherent or incoherent diffraction of matrix plus second-phase particles). The experimental data are shown to be in good to very good agreement with predictions according to the current treatment.

Endothelin-1 in systemic sclerosis.

INTRODUCTION: Scleroderma is a systemic disorder with unknown etiology most notably characterized by skin thickening and organ damage. Endothelin-1 (ET-1) plays a role in skin fibrosis. The aim of this study was survey and comparison of ET-1 level in Systemic Sclerosis (SSc) patients with and without digital ulcer. MATERIAL AND METHODS: A cross-sectional analytical study conducted among the 95 patients with scleroderma in 2006 who were referred to the Rheumatology clinic in Shariati hospital of Tehran. The questionnaire was completed for every patient. Plasma level of endothelin-1 was also measured in all of them. The data was analyzed using SPSS software and statistical tests. RESULTS: The result indicated, relationship among digital ulcers and digital pitting scars with plasma level of ET-1 were significant (P value < 0.05). We could not find any significant relationship between age and plasma level of ET-1. CONCLUSION: These data indicate plasma level of ET-1 in scleroderma patients with digital ulcer was higher than patients without digital ulcer. Thus, increase in plasma level of ET-1 could be effective in vascular damage, fibrosis, and skin thickness.