Interactions between Schistosoma haematobium group species and their Bulinus spp. intermediate hosts along the Niger River Valley

Background Urogenital schistosomiasis, caused by infection with Schistosoma haematobium, is endemic in Niger but complicated by the presence of Schistosoma bovis, Schistosoma curassoni and S. haematobium group hybrids along with various Bulinus snail intermediate host species. Establishing the schistosomes and snails involved in transmission aids disease surveillance whilst providing insights into snail-schistosome interactions/compatibilities and biology. Methods Infected Bulinus spp. were collected from 16 villages north and south of the Niamey region, Niger, between 2011 and 2015. From each Bulinus spp., 20–52 cercariae shed were analysed using microsatellite markers and a subset identified using the mitochondrial (mt) cox1 and nuclear ITS1 + 2 and 18S DNA regions. Infected Bulinus spp. were identified using both morphological and molecular analysis (partial mt cox1 region). Results A total of 87 infected Bulinus from 24 sites were found, 29 were molecularly confirmed as B. truncatus, three as B. forskalii and four as B. globosus. The remaining samples were morphologically identified as B. truncatus (n = 49) and B. forskalii (n = 2). The microsatellite analysis of 1124 cercariae revealed 186 cercarial multilocus genotypes (MLGs). Identical cercarial genotypes were frequently (60%) identified from the same snail (clonal populations from a single miracidia); however, several (40%) of the snails had cercariae of different genotypes (2–10 MLG’s) indicating multiple miracidial infections. Fifty-seven of the B. truncatus and all of the B. forskalii and B. globosus were shedding the Bovid schistosome S. bovis. The other B. truncatus were shedding the human schistosomes, S. haematobium (n = 6) and the S. haematobium group hybrids (n = 13). Two B. truncatus had co-infections with S. haematobium and S. haematobium group hybrids whilst no co-infections with S. bovis were observed. Conclusions This study has advanced our understanding of human and bovid schistosomiasis transmission in the Niger River Valley region. Human Schistosoma species/forms (S. haematobium and S. haematobium hybrids) were found transmitted only in five villages whereas those causing veterinary schistosomiasis (S. bovis), were found in most villages. Bulinus truncatus was most abundant, transmitting all Schistosoma species, while the less abundant B. forskalii and B. globosus, only transmitted S. bovis. Our data suggest that species-specific biological traits may exist in relation to co-infections, snail-schistosome compatibility and intramolluscan schistosome development

Synthesis and characterization of Zn-doped enstatite

Single crystals of Zn-doped enstatite (Mg1-xZnx)SiO3 have been synthesized by slow-cooling flux method using two different fluxes. The starting mixtures were first held at a temperature between 1350 and 950 C, and then slowly cooled to the final temperature (600–750 C) at four different rates. The grown crystals were characterized by binocular microscope, X-ray powder diffraction, scanning electron microscopy with energy dispersive spectrometry. When LiCO3, MoO3 and V2O5 were used as flux, Zn-doped enstatite crystals up to 3.5 mm in length grew successfully. They were transparent in color and showed the typical prismatic form. Chemical analyses on several Zn-doped enstatite crystals showed that the amount of Zn2+ indicated as ZnO wt% ranges from 3.37 to 10.49 wt%. Further characterization by cathodoluminescence and by micro-Raman spectroscopy allowed us to study the effect of zinc dopant on the chemical/physical characteristics of the doped enstatite

Prevalence and community variation in harmful levels of family conflict witnessed by children: implications for prevention

 AbstractChildren’s reports of high family conflict consistently predict poor outcomes. The study identified criteria for high family conflict based on prospective prediction of increased risk for childhood depression. These criteria were subsequently used to establish the prevalence of high family conflict in Australian communities and to identify community correlates suitable for targeting prevention programs. Study 1 utilised a longitudinal design. Grade 6 and 8 students completed a family conflict scale (from the widely used Communities That Care survey) in 2003 and depression symptomotology were evaluated at a 1-year follow-up (International Youth Development Study, N = 1,798). Receiver-operating characteristic analysis yielded a cut-off point on a family conflict score with depression symptomatology as a criterion variable. A cut-off score of 2.5 or more (on a scale of 1 to 4) correctly identified 69 % with depression symptomology, with a specificity of 77.2 % and sensitivity at 44.3 %. Study 2 used data from an Australian national survey of Grade 6 and 8 children (Healthy Neighbourhoods Study, N = 8,256). Prevalence estimates were calculated, and multivariate logistic regression with multi-level modelling was used to establish factors associated with community variation in family conflict levels. Thirty-three percent of Australian children in 2006 were exposed to levels of family conflict that are likely to increase their future risk for depression. Significant community correlates for elevated family conflict included Indigenous Australian identification, socioeconomic disadvantage, urban and state location, maternal absence and paternal unemployment. The analysis provides indicators for targeting family-level mental health promotion programs

Structural basis for the isotype-specific interactions of ferredoxin and ferredoxin: NADP+ oxidoreductase: an evolutionary switch between photosynthetic and heterotrophic assimilation

This work was supported in part by grants-in-aids from the Ministry of Culture, Education, Science and Sports and Technology of Japan and from Japan Science and Technology Agency (JST)