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A recent study confirmed significant contamination of syringe tips following routine anaesthesia practice of at least 6 h in duration. We assessed the relative efficacy of clinically relevant syringe tip disinfection techniques following contamination with the hyper transmissible and more pathogenic Staphylococcus aureus sequence type 5 (S. aureus ST5) strain characteristic associated with increased strength of biofilm formation and greater desiccation tolerance. Syringe tips (N= 40) contaminated with S. aureus ST5 were randomized to 70% isopropyl pads with 10 or 60 s of drying time, scrubbing alcohol disinfection caps with 10 or 60 s of dwell time, or to non-scrubbing alcohol disinfection caps with 60 s of dwell time. The primary outcome was residual 24-h colony forming units (cfu) >10. Scrubbing disinfection caps were more effective than alcohol pads (25% (12/48) <10 cfu for scrubbing caps (10- or 60-s dwell times) vs 0% (0/48) <10 cfu for alcohol pads (10 or 60 s of drying time), Holm–Sidak adjusted P =0.0016). Scrubbing disinfection caps were more effective than non-scrubbing alcohol disinfection caps (25% (12/48) <10 cfu for scrubbing alcohol caps (10- or 60-s dwell times) vs 2% (1/48) for non-scrubbing alcohol caps (60-s dwell time), adjusted P =0.0087). Scrubbing alcohol caps are more effective than alcohol pads or non-scrubbing disinfecting caps for microbial reduction of syringe tips contaminated with the more pathogenic S. aureus ST5. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus sequence type 5 (ST5) is an emerging global threat. To characterize the epidemiology of ST5 transmission in the anaesthesia work area. The retrospective cohort study analysed transmitted, prophylactic antibiotic-resistant Staphylococcus aureus isolates involving anaesthesia work area reservoirs. Using whole-genome analysis, the epidemiology of ST5 transmission was characterized by reservoir(s) of origin, transmission location(s), portal of entry, and mode(s) of transmission. All patients were followed for at least 30 days for surgical site infection (SSI) development. Forty-one percent (18/44; 95% confidence interval: 28–56%) of isolates were ST5. Provider hands were the reservoir of origin for 28% (5/18) of transmitted ST5 vs 4% (1/26) for other STs. Provider hands were the transmission location for 28% (5/18) of ST5 vs 7% (2/26) of other STs. Stopcock contamination occurred for 8% (1/13) of ST5 isolates vs 12% (3/25) of other STs. Sixty-three percent of transmission events occurring between cases on separate operative dates involved ST5. ST5 was more likely to harbour resistance traits (ST5 median (interquartile range) 3 (2–3) vs 2 (1–2) other STs; P < 0.001) and had greater resistance to cefazolin, piperacillin–tazobactam, and/or ciprofloxacin (ST5: 3 (2–3) vs 2 (1–3) other STs; P = 0.02). ST5 was associated with three of six SSIs. ST5 is prevalent among transmitted, prophylactic antibiotic-resistant isolates in the anaesthesia work area. Transmission involves provider hands and one patient to another on future date(s). ST5 is associated with a greater number of resistance traits and reduced in-vitro susceptibility vs other intraoperative meticillin-resistant S. aureus. [ABSTRACT FROM AUTHOR]

The extent to which the transmission of prophylactic-antibiotic-resistant bacteria from the anaesthesia work area increases the risk of surgical site infection (SSI) is unknown. It was hypothesized that the risk of SSI would increase progressively from no transmission to transmission of prophylactic-antibiotic-resistant isolates. This was a retrospective analysis of archival samples collected in two previously published studies with similar inclusion criteria and sample collection methodology (observational study 2009–2010 and randomized trial 2018–2019). Archival isolates were linked by barcode to all patient demographic and procedural information, including the prophylactic antibiotic administered, transmission and development of SSI. For this study, all archival isolates underwent prophylactic antibiotic susceptibility testing, and the ordered association of transmission of Staphylococcus aureus (no transmission, transmission of prophylactic-antibiotic-susceptible isolates and transmission of prophylactic-antibiotic-resistant isolates) with SSI was assessed. The risk of development of SSI was 2% (8/406) without S. aureus transmission, 11% (9/84) with transmission of S. aureus isolates that were susceptible to the prophylactic antibiotic used, and 18% (4/22) with transmission of prophylactic-antibiotic-resistant S. aureus isolates. The Cochrane–Armitage two-sided test for ordered association was P <0.0001. Treating these three groups as 0, 1 and 2, by exact logistic regression, the odds of SSI increased by 3.59 with each unit increase (95% confidence interval 1.92–6.64; P <0.0001). Transmission of S. aureus in the anaesthesia work area reliably increases the risk of SSI, especially when the isolates are resistant to the prophylactic antibiotic administered. [ABSTRACT FROM AUTHOR]

Using a Collison nebulizer, aerosols of influenza (A/Udorn/307/72 H3N2) were generated within a controlled experimental chamber, from known starting virus concentrations. Air samples collected after variable suspension times were tested quantitatively using both plaque and polymerase chain reaction assays, to compare the proportion of viable virus against the amount of detectable viral RNA. These experiments showed that whereas influenza RNA copies were well preserved, the number of viable viruses decreased by a factor of 10(4)-10(5). This suggests that air-sampling studies for assessing infection control risks that detect only influenza RNA may greatly overestimate the amount of viable virus available to cause infection. [ABSTRACT FROM AUTHOR]

Abstract: The Beauty Leaf tree (Calophyllum inophyllum) is a potential source of non-edible vegetable oil for producing future generation biodiesel because of its ability to grow in a wide range of climate conditions, easy cultivation, high fruit production rate, and the high oil content in the seed. This plant naturally occurs in the coastal areas of Queensland and the Northern Territory in Australia, and is also widespread in south-east Asia, India and Sri Lanka. Although Beauty Leaf is traditionally used as a source of timber and orientation plant, its potential as a source of second generation biodiesel is yet to be exploited. In this study, the extraction process from the Beauty Leaf oil seed has been optimised in terms of seed preparation, moisture content and oil extraction methods. The two methods that have been considered to extract oil from the seed kernel are mechanical oil extraction using an electric powered screw press, and chemical oil extraction using n- hexane as an oil solvent. The study found that seed preparation has a significant impact on oil yields, especially in the screw press extraction method. Kernels prepared to 15% moisture content provided the highest oil yields for both extraction methods. Mechanical extraction using the screw press can produce oil from correctly prepared product at a low cost, however overall this method is ineffective with relatively low oil yields. Chemical extraction was found to be a very effective method for oil extraction for its consistence performance and high oil yield, but cost of production was relatively higher due to the high cost of solvent. However, a solvent recycle system can be implemented to reduce the production cost of Beauty Leaf biodiesel. The findings of this study are expected to serve as the basis from which industrial scale biodiesel production from Beauty Leaf can be made. [Copyright &y& Elsevier]

This study explores the potential of the monoglyceride monocaprin as an enhancer of the epithelial permeability of the beta3-adrenoceptor agonist BTA-243, as an approach to improving the bioavailability of this drug. The permeabilities of BTA-243 and mannitol (paracellular marker) in Caco-2 cell monolayer and everted gut sac models in aqueous buffer (pH 6.8) in the presence of 1.3 and 2.0 mM monocaprin were compared with control (monocaprin-free) solutions over a period of 1 h. The transepithelial electrical resistance (TEER) of the Caco-2 cell monolayers was measured at regular time intervals throughout the experiment and after a recovery period of 30 h. Toxicological damage to the biological models associated with exposure to monocaprin was assessed by scanning electron microscopy and by the measurement of lactate dehydrogenase (LDH) release from everted gut sacs. The permeability of BTA-243 in epithelial monolayers was enhanced in the presence of 1.3 and 2.0 mM monocaprin. Measurements of TEER and mannitol permeability showed partial recovery of barrier properties after a 30 h period following exposure to 1.3 mM monocaprin. No structural damage was evident in these monolayers. Enhancement of Caco-2 permeability to BTA-243 by 2.0 mM monocaprin was significantly greater than by 1.3 mM but was irreversible; monolayers failed to recover their barrier properties after 30 h and changes in their gross morphology were observed. The mucosal to serosal transfer of BTA-243 in everted gut sac was enhanced but to a lesser extent than in the Caco-2 model. LDH release from everted gut sacs exposed to monocaprin was significantly less than that after exposure to Triton X-100, a nonionic surfactant known to cause membrane disruption. [Copyright &y& Elsevier]