Vancomycin-resistant enterococci with reduced daptomycin susceptibility in Singapore: prevalence and associated factors.

Prevalence of vancomycin-resistant enterococci (VRE) and use of daptomycin are increasing in Asia. To determine the prevalence of daptomycin non-susceptible enterococci (DNSE) and understand factors associated with reduced daptomycin susceptibility in VRE, we conducted a case-control study in a 1600-bed adult tertiary hospital in Singapore. All VRE isolates from inpatients in 2012 were tested for daptomycin susceptibility. Patients with VRE isolates of daptomycin minimum inhibitory concentration (MIC) ⩾3 µg/ml were classified as daptomycin-reduced susceptible VRE (DRS-VRE) and those with daptomycin MIC 4 µg/ml (DNSE). About half (135, 55%) had reduced susceptibility to daptomycin (MIC 3-4 µg/ml). None in the DS-VRE group had prior exposure to daptomycin. After adjusting for age, gender, comorbidity, hospitalization duration, surgical history, indwelling device use, and duration of antibiotic exposure in the prior 3 months, >1 movement between wards [odds ratio (OR) 0·35, 95% confidence interval (CI) 0·16-0·74, P = 0·006] and minocycline resistance (OR 0·45, 95% CI 0·25-0·84, P = 0·011) were independently associated with DRS-VRE. Our study suggests that daptomycin exposure, >1 movement between wards, and resistance to minocycline, were associated with reduced daptomycin susceptibility in VRE.

Trends in the expression of breastmilk 1993-2003.

The expression of breastmilk is an important strategy to enable mothers to continue exclusive breastfeeding. In some situations, for health or convenience, expressed breastmilk is required and infants fed this way still fall within the definition of exclusive breastfeeding. The aim of this study was to document the changes in rates of breastmilk expression between the first Perth Infant Feeding Study (PIFS I) in 1992-03 and PIFS II in 2002-03. The proportion of mothers expressing breastmilk peaked in the first six weeks, at 38% for PIFS I and 69% for PIFS II. The proportion of mothers who had expressed breastmilk had almost doubled in the decade between studies. The proportion of mothers expressing declined to about 28% of mothers at 22 weeks for PIFS II and slightly less in PIFS I. Breastmilk expression is a very useful skill to allow mothers to exclusively breastfeed until six months and should be taught to all mothers.

Decreased bispectral index as an indicator of syncope before hypotension and bradycardia in two patients with needle phobia.

We report two cases who exhibited a decrease in their bispectral index (BIS) score, associated with syncope during venipuncture in patients with suspected needle phobia. In case 1, the reduction in BIS score occurred during the development of hypotension and bradycardia and may well have been caused by cerebral hypoperfusion. In case 2, the patient lost consciousness with decreasing BIS score before hypotension and bradycardia; this patient's condition could not be completely explained by cerebral hypoperfusion as a result of a vasovagal reflex because the patient's blood pressure and heart rate remained normal during the syncopal episode.

Shrimp chitin as substrate for fungal chitin deacetylase.

The fungal chitin deacetylases (CDA) studied so far are able to perform heterogeneous enzymatic deacetylation on their solid substrate, but only to a limited extent. Kinetic data show that about 5-10% of the N-acetyl glucosamine residues are deacetylated rapidly. Thereafter enzymatic deacetylation is slow. In this study, chitin was exposed to various physical and chemical conditions such as heating, sonicating, grinding, derivatization and interaction with saccharides and presented as a substrate to the CDA of the fungus Absidia coerulea. None of these treatments of the substrate resulted in a more efficient enzymatic deacetylation. Dissolution of chitin in specific solvents followed by fast precipitation by changing the composition of the solvent was not successful either in making microparticles that would be more accessible to the enzyme. However, by treating chitin in this way, a decrystallized chitin with a very small particle size called superfine (SF) chitin could be obtained. This SF chitin, pretreated with 18% formic acid, appeared to be a good substrate for fungal deacetylase. This was confirmed both by enzyme-dependent deacetylation measured by acetate production as well as by isolation and assay for the degree of deacetylation (DD). In this way chitin (10% DD) was deacetylated by the enzyme into chitosan with DD of 90%. The formic acid treatment reduced the molecular weight of the polymeric chain from 2x10(5) in chitin to 1.2 x 10(4) in the chitosan product. It is concluded that nearly complete enzymatic deacetylation has been demonstrated for low-molecular chitin.