6 research outputs found
Comparative Analysis of the Global Transcriptome of Anopheles funestus from Mali, West Africa
Background: Anopheles funestus is a principal vector of malaria across much of tropical Africa and is considered one of the most efficient of its kind, yet studies of this species have lagged behind those of its broadly sympatric congener, An. gambiae. In aid of future genomic sequencing of An. funestus, we explored the whole body transcriptome, derived from mixed stage progeny of wild-caught females from Mali, West Africa. Principal Findings: Here we report the functional annotation and comparative genomics of 2,005 expressed sequence tags (ESTs) from An. funestus, which were assembled with a previous EST set from adult female salivary glands from the same mosquito. The assembled ESTs provided for a nonredundant catalog of 1,035 transcripts excluding mitochondrial sequences. Conclusions/Significance: Comparison of the An. funestus and An. gambiae transcriptomes using computational and macroarray approaches revealed a high degree of sequence identity despite an estimated 20–80 MY divergence time between lineages. A phylogenetically broader comparative genomic analysis indicated that the most rapidly evolving proteins – those involved in immunity, hematophagy, formation of extracellular structures, and hypothetical conserved proteins – are those that probably play important roles in how mosquitoes adapt to their nutritional and externa
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Probiotics, prebiotics, and the host microbiome: the science of translation
Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions
Antigenic Variation in Plasmodium falciparum Malaria Involves a Highly Structured Switching Pattern
Many pathogenic bacteria, fungi, and protozoa achieve chronic infection through
an immune evasion strategy known as antigenic variation. In the human malaria
parasite Plasmodium falciparum, this involves transcriptional
switching among members of the var gene family, causing
parasites with different antigenic and phenotypic characteristics to appear at
different times within a population. Here we use a genome-wide approach to
explore this process in vitro within a set of cloned parasite
populations. Our analyses reveal a non-random, highly structured switch pathway
where an initially dominant transcript switches via a set of
switch-intermediates either to a new dominant transcript, or back to the
original. We show that this specific pathway can arise through an evolutionary
conflict in which the pathogen has to optimise between safeguarding its limited
antigenic repertoire and remaining capable of establishing infections in
non-naïve individuals. Our results thus demonstrate a crucial role for
structured switching during the early phases of infections and provide a
unifying theory of antigenic variation in P. falciparum malaria
as a balanced process of parasite-intrinsic switching and immune-mediated
selection
Preventing preterm births: analysis of trends and potential reductions with interventions in 39 countries with very high human development index.
BACKGROUND: Every year, 1·1 million babies die from prematurity, and many survivors are disabled. Worldwide, 15 million babies are born preterm (<37 weeks' gestation), with two decades of increasing rates in almost all countries with reliable data. The understanding of drivers and potential benefit of preventive interventions for preterm births is poor. We examined trends and estimate the potential reduction in preterm births for countries with very high human development index (VHHDI) if present evidence-based interventions were widely implemented. This analysis is to inform a rate reduction target for Born Too Soon. METHODS: Countries were assessed for inclusion based on availability and quality of preterm prevalence data (2000-10), and trend analyses with projections undertaken. We analysed drivers of rate increases in the USA, 1989-2004. For 39 countries with VHHDI with more than 10,000 births, we did country-by-country analyses based on target population, incremental coverage increase, and intervention efficacy. We estimated cost savings on the basis of reported costs for preterm care in the USA adjusted using World Bank purchasing power parity. FINDINGS: From 2010, even if all countries with VHHDI achieved annual preterm birth rate reductions of the best performers for 1990-2010 (Estonia and Croatia), 2000-10 (Sweden and Netherlands), or 2005-10 (Lithuania, Estonia), rates would experience a relative reduction of less than 5% by 2015 on average across the 39 countries. Our analysis of preterm birth rise 1989-2004 in USA suggests half the change is unexplained, but important drivers include non-medically indicated labour induction and caesarean delivery and assisted reproductive technologies. For all 39 countries with VHHDI, five interventions modelling at high coverage predicted a 5% relative reduction of preterm birth rate from 9·59% to 9·07% of livebirths: smoking cessation (0·01 rate reduction), decreasing multiple embryo transfers during assisted reproductive technologies (0·06), cervical cerclage (0·15), progesterone supplementation (0·01), and reduction of non-medically indicated labour induction or caesarean delivery (0·29). These findings translate to roughly 58,000 preterm births averted and total annual economic cost savings of about US$3 billion. INTERPRETATION: We recommend a conservative target of a relative reduction in preterm birth rates of 5% by 2015. Our findings highlight the urgent need for research into underlying mechanisms of preterm births, and development of innovative interventions. Furthermore, the highest preterm birth rates occur in low-income settings where the causes of prematurity might differ and have simpler solutions such as birth spacing and treatment of infections in pregnancy than in high-income countries. Urgent focus on these settings is also crucial to reduce preterm births worldwide. FUNDING: March of Dimes, USA, Eunice Kennedy Shriver National Institute of Child Health and Human Development, and National Institutes of Health, USA
Adsorption of ciprofloxacin to urinary catheters and effect on subsequent bacterial adhesion and survival
Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions. © 2013 The Authors. Annals of the New York Academy ofx Sciences published by Wiley Periodicals, Inc. on behalf of New York Academy of Sciences