The metric matters when assessing diversity: Assessing lepidopteran species richness and diversity in two habitats under different disturbance regimes

How we measure diversity can have important implications for understanding the impacts of anthropogenic pressure on ecosystem processes and functioning. Functional diversity quantifies the range and relative abundance of functional traits within a given community and, as such, may provide a more mechanistic understanding of ecosystems. Here, we use a novel approach to examine how lepidopteran richness and diversity, weighted by species abundance, differ between habitats under different disturbance regimes (highly disturbed non‐native plantations and less disturbed broadleaf woodlands), both with and without constraining by similarity due to shared taxonomy or functional traits. Comparisons of diversity between the two habitats differed according to which metric was being used; while species richness was 58% greater in broadleaf woodlands, after accounting for species similarity due to shared functional traits, there was little difference between woodland types under two different disturbance regimes. Functional diversity varied within the landscape but was similar in paired broadleaf and plantation sites, suggesting that landscape rather than local factors drive biotic homogenization in plantation dominated landscapes. The higher richness in broadleaf sites appears to be driven by rare species, which share functional traits with more common species. Moth populations in disturbed, plantation sites represent a reduced subset of moth species compared to broadleaf sites, and may be more vulnerable to disturbance pressures such as clear‐felling operations due to low community resilience

First-time- and repeat testers for HIV : a demographic and HIV prevalence comparison amongst clients at mobile HIV Counselling and Testing sites in Tshwane, South Africa

There has been significant debate, specifically within the African context, regarding the validity of using HCT data as part of routine surveillance data for the HIV epidemic. The use of HCT data in tracking the prevalence of HIV, as well as in estimating incidence rates for HIV, has been applied in some African countries, and may offer opportunities to strengthen surveillance in the Gauteng Province, South Africa. Literature suggests HCT data are biased as a result of the high proportion of repeat testers, where repeat testing may be related to high risk sexual behaviour. (1–8) It has been suggested that HCT data be separated into first-time- and repeat tester data in prevalence or incidence estimations. (9) The aim of this research was to determine if there are demographic and HIV prevalence differences between first-time- and repeat testers, as suggested in the literature. (9) Existing mobile HCT unit data was used from the Foundation for Professional Development (FPD). The data was collected in the Tshwane Metropolitan Municipality, Gauteng Province, South Africa. An observational, cross-sectional study design was applied. A systematic random sample of 400 first-time testers and 400 repeat-testers was drawn and analyzed. The findings of this study indicated an overall 10.0% (n=80) HIV prevalence rate. When compared to the Gauteng adult prevalence (15+) of 14.4%, the study prevalence is lower. (10) When looking at the characteristics of the first-time tester and repeat tester groups, there was an HIV prevalence rate of 12.5% (n=51/407, p=0.0152) in the first-time tester group, and 7.4% (n=29/393, p=0.0152) HIV prevalence rate in the repeat tester group. Although literature suggests that repeat testers are the more at risk population, the finding in this study clearly demonstrates that there is a difference in HIV prevalence between first-time- and repeat testers. When first-time/repeat tester was used as the dependent variable, it was found that females are 0.6 less times likely to be a first-time tester compared to males (OR=0.6, p=0.001). The finding of a difference in HIV prevalence between first-time- and repeat tester groups was consistent with three other studies in Ethiopia, Uganda and Kenya. In these studies, HIV prevalence in first-time testers was slightly higher than in that of repeat-testers. (3,11,12) It was found that there is a difference in the HIV and demographic profile between those who test for HIV for the first time and those who are repeat testers. The perceived risk and vulnerability to HIV plays a heavy role in motivating individuals to test once, or repeatedly. In regards to disease surveillance, this study did not prove that the population that utilises mobile HCT are representative of the Tshwane population. This study highlighted the need to better understand the sub-groups and characteristics of those who test for the first-time and those who test repeatedly for HIV. In conclusion, this study has provided evidence that there is a difference between the HIV prevalence of first-time- and repeat testers. However, there is good reason to doubt that the prevalence rate of first-time testers is genuine. CopyrightDissertation (MSc)--University of Pretoria, 2013.School of Health Systems and Public Health (SHSPH)Unrestricte

Antibiotics and oral contraceptive failure - a case-crossover study

Background: Evidence on the association between antibiotic use and combined oral contraceptive (COC) failure is controversial. We examined the effect of concomitant antibiotic treatment on the risk of breakthrough pregnancy among COC users. Study Designs: We performed a case-crossover study of 1330 COC failure cases among 17,721 women from the Slone Epidemiology Center Birth Defects Study (1997-2008) and among 25,941 women from the National Birth Defects Prevention Study (NBDPS, 1997-2005). Self-matched odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by comparing antibiotic use between the 4 weeks before conception ("case period") and the 4-8 weeks before conception ("control period") using conditional logistic regression. A case time-control analysis was conducted using nonusers of COCs with unplanned pregnancies as controls. Results: For the combined data, the self-matched OR was 1.08 (95% CI: 0.63-1.84) and the case time-control OR was 1.12 (0.63-1.98) for antibiotics overall. The results did not appreciably differ when adjusted for characteristics that might vary between the case and control period. However, among COC failure cases from the NBDPS, allowing a 1-month gap between the case and control period resulted in a self-matched OR of 1.45 (0.85-2.50) and a case time-control OR of 1.55 (0.86-2.79) for antibiotics overall. Conclusions: We did not find an association between concomitant antibiotic use and the risk of breakthrough pregnancy among COC users. However, due to limited power and potential carryover effects, findings from this study cannot rule out an elevated risk of COC failure among antibiotic users. (C) 2011 Elsevier Inc. All rights reserved

1980s–2010s: the world’s largest mangrove ecosystem is becoming homogenous

Knowledge gaps in spatiotemporal changes in mangrove diversity and composition have obstructed mangrove conservation programs across the tropics, but particularly in the Sundarbans (10,017 km2), the world's largest remaining natural mangrove ecosystem. Using mangrove tree data collected from Earth's largest permanent sample plot network at four historical time points (1986, 1994, 1999 and 2014), this study establishes spatially explicit baseline biodiversity information for the Sundarbans. We determined the spatial and temporal differences in alpha, beta, and gamma diversity in three ecological zones (hypo-, meso-, and hypersaline) and also uncovered changes in the mangroves' overall geographic range and abundances therein. Spatially, the hyposaline mangrove communities were the most diverse and heterogeneous in species composition while the hypersaline communities were the least diverse and most homogeneous at all historical time points. Since 1986, we detect an increasing trend of compositional homogeneity (between-site similarity in species composition) and a significant spatial contraction of distinct and diverse areas over the entire ecosystem. Temporally, the western and southern hypersaline communities have undergone radical shifts in species composition due to population increase and range expansion of the native invasive species Ceriops decandra and local extinction or range contraction of specialists including the globally endangered Heritiera fomes. The surviving biodiversity hotspots are distributed outside the legislated protected area network. In addition to suggesting the immediate coverage of these hotspots under protected area management, our novel biodiversity insights and spatial maps can form the basis for spatial conservation planning, biodiversity monitoring and protection initiatives for the Sundarbans

Development of high-resolution 3D printable polymerizable ionic liquids for antimicrobial applications

In recent years, 3D printing has undergone a significant transformation, expanding beyond its initial niche applications, such as rapid prototyping and hobbyist projects. This evolution has been characterized by advancements in equipment, software, and, most notably, materials. However, the development of materials that present high-resolution and advanced tunable functionalities is still a challenge. Herein, we report the development of modular 3D-printable antimicrobial polymeric ionic liquid (PIL) scaffolds with in situ formation of copper-based nanoparticles within the polymeric matrix (Cu@PILs). A variety of formulations were specially designed and optimized to be printed by digital light processing and masked stereolithography techniques at high resolution. The antimicrobial activity as well as the biocompatibility of the different formulations was tested, changing the monomeric ionic liquid and the photoinitiator. Tailor-made objects were successfully manufactured, and as a demonstrator, a geometry compatible with a medical stent was printed

Identification of Phthalates in Medications and Dietary Supplement Formulations in the United States and Canada

Background: In animal studies, some ortho-phthalates, including di(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP), have been shown to be reproductive and developmental toxicants. Human studies show widespread population exposure to background levels of phthalates. Limited evidence suggests that particularly high exposure levels may result from orally ingested medicinal products containing phthalates as excipients (inactive ingredients)

Polarized Cytokine Release Triggered by P2X7 Receptor from Retinal Pigmented Epithelial Cells Dependent on Calcium Influx

Cytokine release from non-inflammatory cells is a key step in innate immunity, and agonists triggering cytokine release are central in coordinating responses. P2X7 receptor (P2X7R) stimulation by extracellular ATP is best known to active the NLRP3 inflammasome and release IL-1β, but stimulation also leads to release of other cytokines. As cytokine signaling by retinal pigmented epithelial (RPE) cells is implicated in retinal neurodegeneration, the role of P2X7R in release of cytokine IL-6 from RPE cells was investigated. P2X7R stimulation triggered IL-6 release from primary mouse RPE, human iPS-RPE and human ARPE-19 cells. IL-6 release was polarized, with predominant rise across apical membranes. IL-6 release was inhibited by P2X7R antagonists A438079, A839977, and AZ10606120, but not the NRTI lamivudine (3TC), P2X1R antagonist NF279, or P2Y1R antagonist MRS2179. P2X7R-mediated IL-6 release required extracellular Ca2+ and was blocked by Ca2+ chelator BAPTA. IL-6 release and Ca2+ elevation occurred rapidly, consistent with vesicular IL-6 staining in unstimulated cells. P2X7R stimulation did not trigger IL-1β release in these unprimed cells. P2X7R-mediated IL-6 release was enhanced in RPE cells from the ABCA4-/- mouse model of retinal degeneration. In summary, P2X7R stimulation triggers rapid Ca2+-dependent IL-6 release across the apical membrane of RPE cells

Approaches for Detecting Lysosomal Alkalinization and Impaired Degradation in Fresh and Cultured RPE Cells: Evidence for a Role in Retinal Degenerations

Lysosomes contribute to a multitude of cellular processes, and the pH of the lysosomal lumen plays a central mechanistic role in many of these functions. In addition to controlling the rate of enzymatic degradation for material delivered through autophagic or phagocytotic pathways, lysosomal pH regulates events such as lysosomal fusion with autophagosomes and the release of lysosomal calcium into the cytoplasm. Disruption of either the steady state lysosomal pH or of the regulated manipulations to lysosomal pH may be pathological. For example, chloroquine elevates the lysosomal pH of retinal pigmented epithelial (RPE) cells and triggers a retinopathy characterized by the accumulation of lipofuscin-like material in both humans and animals. Compensatory responses to restore lysosomal pH are observed; new data illustrate that chronic chloroquine treatment increases mRNA expression of the lysosomal/autophagy master transcription factor TcFEB and of the vesicular proton pump vHATPase in the RPE/choroid of mice. An elevated lysosomal pH with upregulation of TcFEB and vHATPase resembles the pathology in fibroblasts of patients with mutant presenilin 1 (PS1), suggesting a common link between age-related macular degeneration (AMD) and Alzheimer\u27s disease. While the absolute rise in pH is often small in these disorders, elevations of only a few tenths of a pH unit can have a major impact on both lysosomal function and the accumulation of waste over decades. Accurate measurement of lysosomal pH can be complex, and imprecise measurements have clouded the field. Protocols to optimize pH measurement from fresh and cultured cells are discussed, and indirect measurements to confirm changes in lysosomal pH and degradative capacity are addressed. The ability of reacidifying treatments to restore degradative function confirms the central role of lysosomal pH in these disorders and identifies potential approaches to treat diseases of lysosomal accumulation like AMD and Alzheimer\u27s disease. In summary, various approaches to determine lysosomal pH in fresh and cultured cells, as well as the potential to restore pH levels to an optimal range, can help identify and repair pathologies associated with lysosomal defects in RPE cells and perhaps also suggest new approaches to treat lysosomal storage diseases throughout the body. © 2014 Elsevier Ltd