Deactivation of the ruthenium excited state by enhanced homogeneous charge transport: Implications for electrochemiluminescent thin film sensors

peer-reviewedThe electrochemiluminescent (ECL) performance of three ruthenium-based metallopolymer platforms with different homogeneous charge transfer diffusion coefficients (DCT) is reported. Significantly, simultaneous detection of light and current in tandem with steady-state photoluminescence studies demonstrate that increasing the rate of Ru3 + production via enhanced charge transport results in a decrease in ECL intensity of up to 82% when the concentration of the co-reactant, sodium oxalate, is low, i.e., sub-mM. Spectroelectrochemical studies demonstrate that for maximum sensitivity to be obtained, the electroactive properties of the polymeric support matrix need to be considered in tandem with luminophore, analyte and co-reactant concentrations

Melioidosis, Northeastern Brazil

Melioidosis was first recognized in northeastern Brazil in 2003. Confirmation of additional cases from the 2003 cluster in Ceará, more recent cases in other districts, environmental isolation of Burkholderia pseudomallei, molecular confirmation and typing results, and positive serosurveillance specimens indicate that melioidosis is more widespread in northeastern Brazil than previously thought

Comparison of Rapid, Automated Ribotyping and DNA Macrorestriction Analysis of Burkholderia pseudomallei

An automated ribotyping device (RiboPrinter) was used to determine the ribotypes of a collection of Burkholderia pseudomallei isolates. In a preliminary evaluation with the restriction enzymes BamHI and EcoRI, the protocol with EcoRI was more discriminating. The reproducibilities of the ribotypes obtained with EcoRI (EcoRI ribotypes) were determined by testing three levels of bacterial loads. The performance of the manufacturer's software was assessed by comparing the machine-optimized ribotypes with the type determined from the original gel image analyzed with Bionumerics software. The library of B. pseudomallei EcoRI ribotypes was then compared with the ribotypes obtained by DNA macrorestriction analysis of XbaI digests by pulsed-field gel electrophoresis. The typeability of B. pseudomallei by EcoRI ribotyping was 100%, and the discrimination index was 0.94. The slightly greater discrimination provided by DNA macrorestriction analysis (0.96) was achieved at the expense of a significantly longer processing time of 6 days, although the method was only half the cost of automated ribotyping. Typeability by macrorestriction analysis was lower (97%) unless a thiourea step was added to neutralize the action of Tris-dependent endonucleases. The digital record of B. pseudomallei isolates analyzed thus far provides a useful resource for future epidemiological studies and will help shorten the response time in the event of a further melioidosis outbreak or the deliberate release of B. pseudomallei as a biohazard

Multiplex Amplified Nominal Tandem-Repeat Analysis (MANTRA), a Rapid Method for Genotyping Mycobacterium tuberculosis by Use of Multiplex PCR and a Microfluidic Laboratory Chip ▿

A variable-number tandem-repeat genotyping method for Mycobacterium tuberculosis was converted to run in a multiplex PCR format on a 12-well microfluidic laboratory chip. Epidemiologically and genotypically distinct isolate clusters of M. tuberculosis were identified. This rapid genotyping method has potential application in smaller clinical laboratories and public health field investigations

Emergence of multi-resistant Pseudomonas aeruginosa in a Western Australian hospital

Multi-resistant Pseudomonas aeruginosa (MRPa) has been isolated from patients in a Western Australian teaching hospital with increasing frequency since first encountered in 2006. Between 2006 and 2008 the number of patients with MRPa increased from three to nine per annum, and their location shifted from intensive care to a high dependency unit. A novel water-saving device (aerator) in a staff hand basin was identified as a likely disseminator, with MRPa being isolated from biofilm in the basin's plumbing. The disposal of patient waste, surplus intravenous antibiotic infusions and solid items via hand basins were possible contributory factors. Genotyping of MRPa from patients in other hospitals showed distinct genotypic lineages. The third seasonal cluster persisted for longer, indicating adaption to environment. More effective environmental control of P. aeruginosa is urgently needed

Substitution of sugar-sweetened beverages for other beverages and the risk of developing coronary heart disease:Results from the Harvard Pooling Project of Diet and Coronary Disease

Epub 2019 Dec 26

Association between the intake of α-linolenic acid and the risk of CHD

Intake of the mainly plant derived n-3 polyunsaturated fatty acid (PUFA) α-linolenic acid (ALA) has been associated with lower risk of coronary heart disease (CHD). However, the results have been inconsistent. Therefore, the objective of this study was to examine the association between ALA consumption and risk of CHD. Potential effect modification by long-chain n-3 PUFA (n-3 LCPUFA) was also investigated. Data from eight American and European prospective cohort studies including 148,675 women and 80,368 men were used. The outcome measure was incident CHD (CHD event and death). During follow-up of 4-10 years, 4,493 CHD events and 1,751 CHD deaths occurred. Among men we found an inverse association (not significant) between intake of ALA and CHD event and death. For each additional gram of ALA, there was a 15% lower risk of CHD events (HR: 0.85; 95% CI: 0.72, 1.01) and a 23% lower risk of CHD deaths (HR: 0.77; 95% CI 0.58, 1.01). We found no consistent associations among women. No effect modification by intake of n-3 LCPUFA was found

Multilocus sequence typing of Campylobacter jejuni isolates from New South Wales, Australia

Aims: Multilocus sequence typing (MLST) was used to examine the diversity and population structure of Campylobacter jejuni isolates associated with sporadic cases of gastroenteritis in Australia, and to compare these isolates with those from elsewhere. Methods and Results: A total of 153 Camp. jejuni isolates were genotyped. Forty sequence types (STs) were found, 19 of which were previously undescribed and 21 identified in other countries. The 19 newly described STs accounted for 43% of isolates, 16 of which were assigned to known clonal complexes. Eighty-eight percent of isolates were assigned to a total of 15 clonal complexes. Of these, four clonal complexes accounted for 60% of isolates. Three STs accounted for nearly 40% of all isolates and appeared to be endemic, while 21 STs were represented by more than one isolate. Seven infections were acquired during international travel, and the associated isolates all had different STs, three of which were exclusive to the travel-acquired cases. Comparison of serotypes among isolates from clonal complexes revealed further diversity. Eight serotypes were identified among isolates from more than one clonal complex, while isolates from six clonal complexes displayed serotypes not previously associated with those clonal complexes. Conclusions: Multilocus sequence typing is a useful tool for the discrimination of subtypes and examination of the population structure of Camp. jejuni associated with sporadic infections. Significance and Impact of the Study: This study highlights the genotypic diversity of Camp. jejuni in Australia, demonstrating that STs causing disease have both a global and a local distribution evident from the typing of domestically and internationally acquired Camp. jejuni isolates