Low Phytoestrogen Levels in Feed Increase Fetal Serum Estradiol Resulting in the “Fetal Estrogenization Syndrome” and Obesity in CD-1 Mice

doi:10.1289/ehp.10448Although estrogenic chemicals can disrupt development of the reproductive system, there is debate about whether phytoestrogens in soy are beneficial, benign, or harmful. We compared reproductive and metabolic characteristics in male and female mice reared and maintained on non-soy low-phytoestrogen feed or soy-based high-phytoestrogen feed. Removing phytoestrogens from mouse feed produces an obese phenotype consistent with metabolic syndrome, and the associated reproductive system abnormalities are consistent with FES due to elevated endogenous fetal estradiol. Laboratory rodents may have become adapted to high-phytoestrogen intake over many generations of being fed soy-based commercial feed; removing all phytoestrogens from feed leads to alterations that could disrupt many types of biomedical research

Meningococcal carriage within households in the African meningitis belt: A longitudinal pilot study.

OBJECTIVES: Carriers of Neisseria meningitidis are a key source of transmission. In the African meningitis belt, where risk of meningococcal disease is highest, a greater understanding of meningococcal carriage dynamics is needed. METHODS: We randomly selected an age-stratified sample of 400 residents from 116 households in Bamako, Mali, and collected pharyngeal swabs in May 2010. A month later, we enrolled all 202 residents of 20 of these households (6 with known carriers) and collected swabs monthly for 6 months prior to MenAfriVac vaccine introduction and returned 10 months later to collect swabs monthly for 3 months. We used standard bacteriological methods to identify N. meningitidis carriers and fit hidden Markov models to assess acquisition and clearance overall and by sex and age. RESULTS: During the cross-sectional study 5.0% of individuals (20/400) were carriers. During the longitudinal study, 73 carriage events were identified from 1422 swabs analyzed, and 16.3% of individuals (33/202) were identified as carriers at least once. The majority of isolates were non-groupable; no serogroup A carriers were identified. CONCLUSIONS: Our results suggest that the duration of carriage with any N. meningitidis averages 2.9 months and that males and children acquire and lose carriage more frequently in an urban setting in Mali. Our study informed the design of a larger study implemented in seven countries of the African meningitis belt

The PREDICTS database: a global database of how local terrestrial biodiversity responds to human impacts

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species’ threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project – and avert – future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups – including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems – www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015

Conservation of the <i>fHbpRd2R</i> primer binding site.

<p>Single dots denote bases matching that of the PCR primer (Top sequence, 3′–5′ direction). Sequence A is representative of 438/443 (98.8%) meningococcal isolates aligned (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0089921#pone.0089921.s003" target="_blank">Table S2</a>). Sequence B features the <i>fHbpRd2R</i> primer site mismatch. This was found in two isolates within the MGL (0.22%) and 25% of <i>N. lactamica</i> sequences aligned.</p

Genotypic Analysis of Meningococcal Factor H-Binding Protein from Non-Culture Clinical Specimens

<div><p>Factor H-Binding Protein (fHbp) is an outer membrane protein antigen included in two novel meningococcal group B vaccines and, as such, is an important typing target. Approximately 50% of meningococcal disease cases in England and Wales are confirmed using real-time PCR on non-culture clinical specimens only. Protocols for typing fHbp from this subset of cases have not yet been established. Here we present a nested PCR-based assay designed to amplify and sequence <i>fHbp</i> from non-culture clinical specimens. From analytical sensitivity experiments carried out using diluted DNA extracts, an estimated analytical sensitivity limit of 6 fg/µL of DNA (<3 genome copies/µL) was calculated. The sensitivity of the assay was shown to be comparable to the <i>ctrA</i>-directed real-time PCR assay currently used to confirm invasive disease diagnoses from submitted clinical specimens. A panel of 96 diverse, patient-matched clinical specimen/isolate pairs from invasive disease cases was used to illustrate the breadth of strain coverage for the assay. All <i>fHbp</i> alleles sequenced from the isolates matched those derived from previous whole genome analyses. The first-round PCR primer binding sites are highly conserved, however an exceptional second-round PCR primer site mismatch in one validation isolate prevented amplification. In this case, amplification from the corresponding clinical specimen was achieved, suggesting that the use of a nested PCR procedure may compensate for any minor mismatches in round-two primer sites. The assay was successful at typing 91/96 (94.8%) of the non-culture clinical specimens in this study and exhibits sufficient sensitivity to type <i>fHbp</i> from the vast majority of non-culture clinical specimens received by the Meningococcal Reference Unit, Public Health England.</p></div

Ct values generated using real-time TaqMan PCR assay.

<p>Ct values generated using real-time TaqMan PCR assay.</p

PCR and sequencing primers.

<p>PCR and sequencing primers.</p

Serial dilutions of meningococcal extracts, corresponding estimated DNA concentration and calculated genome copy number (estimate based upon a 2.2 Mbp genome).

<p>Serial dilutions of meningococcal extracts, corresponding estimated DNA concentration and calculated genome copy number (estimate based upon a 2.2 Mbp genome).</p

Standard nested-PCR mastermix reagent volumes.

<p>Standard nested-PCR mastermix reagent volumes.</p

Gel image of amplicons produced using varying extract volumes.

<p>Annotated gel image of round two PCR products from nested PCR using varying volumes of diluted DNA extracts in the preceding round one reaction. The products for all seven isolate extracts at the highest two dilutions are shown. Wells to the left of the image contain 10⁻⁷ dilution extracts (600 ag/µL) and wells adjacent to the molecular weight ladder contain 10⁻⁸ dilution extracts (60 ag/µL). The extract/reaction volumes (µL) are indicated on the right of the image. Extract numbers refer to the order in which the isolates are listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0089921#pone.0089921.s002" target="_blank">Table S1</a>. ML = Molecular ladder.</p