26 research outputs found
Application of targeted molecular and material property optimization to bacterial attachment-resistant (meth)acrylate polymers
Developing medical devices that resist bacterial attachment and subsequent biofilm formation is highly desirable. In this paper, we report the optimization of the molecular structure and thus material properties of a range of (meth)acrylate copolymers which contain monomers reported to deliver bacterial resistance to surfaces. This optimization allows such monomers to be employed within novel coatings to reduce bacterial attachment to silicone urinary catheters. We show that the flexibility of copolymers can be tuned to match that of the silicone catheter substrate, by copolymerizing these polymers with a lower Tg monomer such that it passes the flexing fatigue tests as coatings upon catheters, that the homopolymers failed. Furthermore, the Tg values of the copolymers are shown to be readily estimated by the Fox equation. The bacterial resistance performance of these copolymers were typically found to be better than the neat silicone or a commercial silver containing hydrogel surface, when the monomer feed contained only 25 v% of the “hit” monomer. The method of initiation (either photo or thermal) was shown not to affect the bacterial resistance of the copolymers. Optimized synthesis conditions to ensure that the correct copolymer composition and to prevent the onset of gelation are detailed
Phylogeographical analysis of the dominant multidrug-resistant H58 clade of Salmonella Typhi identifies inter- and intracontinental transmission events.
The emergence of multidrug-resistant (MDR) typhoid is a major global health threat affecting many countries where the disease is endemic. Here whole-genome sequence analysis of 1,832 Salmonella enterica serovar Typhi (S. Typhi) identifies a single dominant MDR lineage, H58, that has emerged and spread throughout Asia and Africa over the last 30 years. Our analysis identifies numerous transmissions of H58, including multiple transfers from Asia to Africa and an ongoing, unrecognized MDR epidemic within Africa itself. Notably, our analysis indicates that H58 lineages are displacing antibiotic-sensitive isolates, transforming the global population structure of this pathogen. H58 isolates can harbor a complex MDR element residing either on transmissible IncHI1 plasmids or within multiple chromosomal integration sites. We also identify new mutations that define the H58 lineage. This phylogeographical analysis provides a framework to facilitate global management of MDR typhoid and is applicable to similar MDR lineages emerging in other bacterial species
The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2
Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age 6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score 652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701
A model for the provision of jail mental health services: an integrative, community-based approach
Although a considerable amount of attention has been paid to the development and implementation of mental health services in prisons, relatively little work has focused on the provision of such services to jails. Jails generally serve two purposes: (1) they hold inmates awaiting arraignment or trial and (2) they serve as short-term correctional facilities for individuals who have been assigned relatively short sentences (no longer than one or two years). Because inmnates in the first category usually remain in jail for a short period of time, it is particularly challenging to provide them mental health services. This article describes an innovative program that has recently been developed for assessing the mental health needs of inmates awaiting arraignment or trial, and providing them with mental health services
Intrinsic bistability in the electroluminescence spectrum and current-voltage characteristics of triple-barrier p-i-n resonant tunneling devices
The electroluminescence spectrum and current-voltage characteristics of a forward biased triple-barrier p-i-n diode are investigated. The thin AlAs central barrier provides strong coupling between the two GaAs quantum wells. EL arises from the GaAs contact layers and both spatially direct and indirect recombination in the quantum wells. The latter line is much the stronger and shows a marked red shift with increasing bias. Two electron and two hole resonant peaks are observed in I(V) and in the intensity-bias plots of the EL emission lines. A pronounced intrinsic bistability is observed in both I(V) and the EL spectra. The effect of magnetic field on the EL spectra is investigated
Book review: 'Children and Migration in Europe', edited by Ní Laoire, C., Carpena-Méndez, F., Tyrrell, N. & White, A.
A new modified Goldstein-Levitin-Polyakprojection method for variational inequality problems
Age-correlated protein and transcript expression in breast cancer and normal breast tissues is dominated by host endocrine effects
The magnitude and scope of intrinsic age-correlated and host endocrine age-correlated gene
expression in breast cancer is not well understood. From age-correlated gene expression in 3071
breast cancer transcriptomes and epithelial protein expression of 42 markers in 5001 breast cancers and 537 normal breast tissues, we identified a majority of age-correlated genes as putatively
regulated by age-dependent estrogen signaling. Surprisingly these include the chromatin modifier EZH2 with negative age correlation and associated H3K27me3, with an inverse positive age
correlation. Among TCGA-lung, thyroid, kidney and prostate transcriptomes, the largest overlap
with breast cancer in age-correlated transcripts was in lung cancer, where about 1/3 of overlapping
age-correlated transcripts appeared estrogen regulated. Age-quartile stratified outcomes analysis
of 3,500 breast cancers using EZH2, H3K27me3, FOXA1 and BCL2 proteins revealed distinct
age-related prognostic significance. Age correlation in gene expression may thus be an important
factor in ER, EZH2, H3K27me3 and other biomarker assessment and treatment strategies.Medicine, Faculty ofNon UBCCellular and Physiological Sciences, Department ofMedical Genetics, Department ofPathology and Laboratory Medicine, Department ofReviewedFacultyResearcherGraduat
Luminescence studies of resonant tunneling in a triple barrier structure with strongly coupled quantum wells
The electrical and optical properties of an n-oped triple barrier resonant tunneling diode are investigated. A thin central AlAs barrier provides strong coupling between the two GaAs quantum wells which have equal widths. Photoluminescence (PL) arises from both spatially direct and spatially indirect transitions in the quantum wells. The intense spatially indirect transition shows a pronounced red shift with increasing bias. A strong intrinsic bistability effect is observed in one of the three resonant peaks in the current-voltage curve. This effect is also seen in the photon energy and intensity of the PL from the wells. Photoluminescence excitation spectroscopy is used to identify the optical transitions and the strength of the tunneling interaction