Publications by authors named "Chaw K"

Transfusion-transmitted bacterial infection (TTBI) is the leading cause of transfusion-transmitted infections. Platelet components are more likely to be associated with bacterial contamination due to their storage requirements. Australian Red Cross Lifeblood introduced the bacterial contamination screening (BCS) of all platelet components in 2008.

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Malaria, which infected more than 240 million people and killed around six hundred thousand only in 2021, has reclaimed territory after the SARS-CoV-2 pandemic. Together with parasite resistance and a not-yet-optimal vaccine, the need for new approaches has become critical. While earlier, limited, studies have suggested that malaria parasites are affected by electromagnetic energy, the outcomes of this affectation vary and there has not been a study that looks into the mechanism of action behind these responses.

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Objective: To identify characteristics associated with the hospitalisation and death of people with COVID-19 living in residential aged care facilities (RACFs).

Design: Retrospective cohort study.

Setting, Participants: All confirmed (polymerase chain reaction testing) or probable SARS-CoV-2 infections (rapid antigen tests) in residents of the 86 RACFs in the Metro South Hospital and Health Service area (southeast Queensland), 13 December 2021 - 24 January 2022.

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Purpose Of Review: This review summarises the epidemiology of infection and describes contemporary and emerging diagnostic methods for detection and identification of .

Recent Findings: A fifth clade has been described. Diagnostic accuracy has improved with development of selective/differential media for .

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Introduction: This study aims to assess the association of piperacillin/tazobactam and meropenem minimum inhibitory concentration (MIC) and beta-lactam resistance genes with mortality in the MERINO trial.

Methods: Blood culture isolates from enrolled patients were tested by broth microdilution and whole genome sequencing at a central laboratory. Multivariate logistic regression was performed to account for confounders.

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Silver gulls carry phylogenetically diverse , including globally dominant extraintestinal pathogenic (ExPEC) sequence types and pandemic ExPEC-ST131 clades; however, our large-scale study (504 samples) on silver gulls nesting off the coast of New South Wales identified ST457 as the most prevalent. A phylogenetic analysis of whole-genome sequences (WGS) of 138 ST457 samples comprising 42 from gulls, 2 from humans (Australia), and 14 from poultry farmed in Paraguay were compared with 80 WGS deposited in public databases from diverse sources and countries. ST457 strains are phylogenetic group F, carry 145, and partition into five main clades in accordance to predominant flagella H-antigen carriage.

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Object: Value of care is emerging as a promising framework to restructure health care, emphasizing the importance of reporting multiple outcomes that encompass the entire care episode instead of isolated outcomes specific to care points during a patient's care. The authors assessed the impact of coordinated implementation of processes across the episode of surgical care on value of neurosurgical care, using microvascular decompression (MVD) as an example.

Methods: This study is a retrospective review of consecutive cases involving patients with either trigeminal neuralgia or hemifacial spasm undergoing first-time MVD.

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Microtopography is one of several strategies used by marine organisms to inhibit colonization by fouling organisms. While replicates of natural microtextures discourage settlement, details of larval interactions with the structured surfaces remain scarce. Close-range microscopy was used to quantify the exploration of cyprids of Amphibalanus amphitrite on cylindrical micropillars with heights of 5 and 30 μm and diameters ranging from 5 to 100 μm.

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Settlement inhibition of barnacle (Amphibalanus amphitrite) cypris larvae resulting from exposure to ultrasound was measured at three frequencies (23, 63, and 102 kHz), applied at three acoustic pressure levels (9, 15, and 22 kPa) for exposure times of 30, 150, and 300 s. The lowest settlement was observed for 23 kHz, which also induced the highest cyprid mortality. Cyprid settlement following exposure to 23 kHz at 22 kPa for 30 s was reduced by a factor of two.

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The behavioural response of cypris larvae from A. amphitrite (=Balanus amphitrite) exploring three model glass surfaces is quantified by close-range microscopy. Step length and step duration measurements reveal a response to both surface properties and flow.

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Atomic force microscopy (AFM), laboratory settlement assays and field tests were used to correlate cyprid footprint (FP) morphology with the behaviour of cyprids on different substrata. AFM imaging under laboratory conditions revealed more porous and larger FPs on glass exposing a CH3-surface than on aminosilane functionalised (NH2-) surfaces. The secreted FP volume was found to be similar on both substrata (2.

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This paper describes a multi-step microfluidic device for studying the deformation and extravasation of primary tumor cells. Prior to extravasation, primary tumor cells undergo sequential steps of deformation through the capillaries, before adhering and transmigrating through the endothelial lining and basement membrane. To study this cascade of events, we fabricated a multi-step microfluidic device whose microgaps were coated with Matrigel to mimic the basement membrane.

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Three-dimensional (3-D) extracellular matrices (ECM) allow complex biochemical and biophysical interactions between cells and matrices. Unlike 2-D systems, 3-D models provide a better representation of the micro and local environments in living tissues for facilitating the physiological study of cell migration. Here, we report a microfluidic device based on polydimethylsiloxane (PDMS) for monitoring 3-D cell migration across ECM-coated microgaps with real-time light microscopy.

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A microfluidic device was developed for quantifying the migratory and deformability capabilities of a single tumor cell using direct imaging. It was fabricated using photolithography and is made of polydimethysiloxane. Chemotaxis approach was used for directing cell movement, using 10 microm microgaps to restrict the migration to a single cell.

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In this paper, we report on the potential use of atomic force microscopy (AFM) as a tool to measure the intermolecular forces in biofilm structures and to study the effect of silver ions on sessile Staphylococcus epidermidis cell viability and stability. We propose a strategy of destabilizing the biofilm matrix by reducing the intermolecular forces within the extracellular polymeric substances (EPSs) using a low concentration (50 ppb) of silver ions. Our AFM studies on the intermolecular forces within the EPSs of S.

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