High Hepatitis E Seroprevalence Among Displaced Persons in South Sudan.

AbstractLarge protracted outbreaks of hepatitis E virus (HEV) have been documented in displaced populations in Africa over the past decade though data are limited outside these exceptional settings. Serological studies can provide insights useful for improving surveillance and disease control. We conducted an age-stratified serological survey using samples previously collected for another research study from 206 residents of an internally displaced person camp in Juba, South Sudan. We tested serum for anti-HEV antibodies (IgM and IgG) and estimated the prevalence of recent and historical exposure to the virus. Using data on individuals' serostatus, camp arrival date, and state of origin, we used catalytic transmission models to estimate the relative risk of HEV infection in the camp compared with that in the participants' home states. The age-adjusted seroprevalence of anti-HEV IgG was 71% (95% confidence interval = 63-78), and 4% had evidence of recent exposure (IgM). We estimated HEV exposure rates to be more than 2-fold (hazard ratio = 2.3, 95% credible interval = 0.3-5.8) higher in the camp than in the participants' home states, although this difference was not statistically significant. HEV transmission may be higher than previously appreciated, even in the absence of reported cases. Improved surveillance in similar settings is needed to understand the burden of disease and minimize epidemic impact through early detection and response

Characterisation and In Vitro Antimicrobial Activity of Biosynthetic Silver-loaded Bacterial Cellulose Hydrogels

Wounds that remain in the inflammatory phase for a prolonged period of time are likely to be colonised and infected by a range of commensal and pathogenic microorganisms. Treatment associated with these types of wounds mainly focuses on controlling infection and providing an optimum environment capable of facilitating re-epithelialisation, thus promoting wound healing. Hydrogels have attracted vast interest as moist wound-responsive dressing materials. In the current study, biosynthetic bacterial cellulose hydrogels synthesised by Gluconacetobacter xylinus and subsequently loaded with silver were characterised and investigated for their antimicrobial activity against two representative wound infecting pathogens, namely S. aureus and P. aeruginosa. Silver nitrate and silver zeolite provided the source of silver and loading parameters were optimised based on experimental findings. The results indicate that both AgNO3 and AgZ loaded biosynthetic hydrogels possess antimicrobial activity (p < .05) against both S. aureus and P. aeruginosa and may therefore be suitable for wound management applications

Use of a Cholera Rapid Diagnostic Test during a Mass Vaccination Campaign in Response to an Epidemic in Guinea, 2012

During the 2012 cholera outbreak in the Republic of Guinea, the Ministry of Health, supported by Médecins Sans Frontières - Operational Center Geneva, used the oral cholera vaccine Shanchol as a part of the emergency response. The rapid diagnostic test (RDT) Crystal VC, widely used during outbreaks, detects lipopolysaccharide antigens of Vibrio cholerae O1 and O139, both included in Shanchol. In the context of reactive use of a whole-cell cholera vaccine in a region where cholera cases have been reported, it is essential to know what proportion of vaccinated individuals would be reactive to the RDT and for how long after vaccination

The effect of applied electric field on pulsed radio frequency and pulsed direct current plasma jet array

© 2012 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Physics of Plasmas, 19 (6), 063505 and may be found at http://dx.doi.org/10.1063/1.4729730Here we compare the plasma plume propagation characteristics of a 3-channel pulsed RF plasma jet array and those of the same device operated by a pulsed dc source. For the pulsed-RF jet array, numerous long life time ions and metastables accumulated in the plasma channel make the plasma plume respond quickly to applied electric field. Its structure similar as “plasma bullet” is an anode glow indeed. For the pulsed dcplasma jet array, the strong electric field in the vicinity of the tube is the reason for the growing plasma bullet in the launching period. The repulsive forces between the growing plasma bullets result in the divergence of the pulsed dcplasma jet array. Finally, the comparison of 309 nm and 777 nm emissions between these two jet arrays suggests the high chemical activity of pulsed RF plasma jet array

Transesterification of PHA to Oligomers Covalently Bonded with (Bio)Active Compounds Containing Either Carboxyl or Hydroxyl Functionalities

© 2015 The Authors. Published by Public Library of Science. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1371/journal.pone.0120149This manuscript presents the synthesis and structural characterisation of novel biodegradable polymeric controlled-release systems of pesticides with potentially higher resistance to weather conditions in comparison to conventional forms of pesticides. Two methods for the preparation of pesticide-oligomer conjugates using the transesterification reaction were developed. The first method of obtaining conjugates, which consist of bioactive compounds with the carboxyl group and polyhydroxyalkanoates (PHAs) oligomers, is "one-pot" transesterification. In the second method, conjugates of bioactive compounds with hydroxyl group and polyhydroxyalkanoates oligomers were obtained in two-step method, through cyclic poly(3-hydroxybutyrate) oligomers. The obtained pesticide-PHA conjugates were comprehensively characterised using GPC, 1H NMR and mass spectrometry techniques. The structural characterisation of the obtained products at the molecular level with the aid of mass spectrometry confirmed that both of the synthetic strategies employed led to the formation of conjugates in which selected pesticides were covalently bonded to PHA oligomers via a hydrolysable ester bond

Plasma–liquid interactions: a review and roadmap

Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on non-equilibrium plasmas

The Production and Application of Hydrogels for Wound Management: A Review

Wound treatment has increased in importance in the wound care sector due to the pervasiveness of chronic wounds in the high-risk population including, but not limited to, geriatric population, immunocompromised and obese patients. Furthermore, the number of people diagnosed with diabetes is rapidly growing. According to the World Health Organization (WHO), the global diabetic occurrence has increased from 4.7 in 1980 to 8.5 in 2014. As diabetes becomes a common medical condition, it has also become one of the major causes of chronic wounds which require specialised care to address patients’ unique needs. Wound dressings play a vital role in the wound healing process as they protect the wound site from the external environment. They are also capable of interacting with the wound bed in order to facilitate and accelerate the healing process. Advanced dressings such as hydrogels are designed to maintain a moist environment at the site of application and due to high water content are ideal candidates for wound management. Hydrogels can be used for both exudating or dry necrotic wounds. Additionally, hydrogels also demonstrate other unique features such as softness, malleability and biocompatibility. Nowadays, advanced wound care products make up around 7.1 billion of the global market and their production is growing at an annual rate of 8.3 with the market projected to be worth 12.5 billion by 2022. The presented review focuses on novel hydrogel wound dressings, their main characteristics and their wound management applications. It also describes recent methodologies used for their production and the future potential developments

Wall fluxes of reactive oxygen species of an rf atmospheric-pressure plasma and their dependence on sheath dynamics

This article was published in the serial, Journal of Physics D: Applied Physics [© IOP Publishing Ltd]. The definitive version is available at: http://dx.doi.org/10.1088/0022-3727/45/30/305205A radio-frequency (rf) atmospheric-pressure discharge in He–O2 mixture is studied using a fluid model for its wall fluxes and their dependence on electron and chemical kinetics in the sheath region. It is shown that ground-state O, O+2 and O− are the dominant wall fluxes of neutral species, cations and anions, respectively. Detailed analysis of particle transport shows that wall fluxes are supplied from a boundary layer of 3–300μm immediately next to an electrode, a fraction of the thickness of the sheath region. The width of the boundary layer mirrors the effective excursion distance during lifetime of plasma species, and is a result of much reduced length scale of particle transport at elevated gas pressures. As a result, plasma species supplying their wall fluxes are produced locally within the boundary layer and the chemical composition of the overall wall flux depends critically on spatio-temporal characteristics of electron temperature and density within the sheath. Wall fluxes of cations and ions are found to consist of a train of nanosecond pulses, whereas wall fluxes of neutral species are largely time-invariant