Bacterial filtration efficiency of green soy protein based nanofiber air filter

High bacterial filtration efficiency (BFE) filters, based on nanofibers derived from blends of grain proteins and poly-ethylene-oxide (PEO), were produced by an electrospinning process. Specifically, polymer blends consisting of purified soy flour/PEO with a ratio of 7/3 were spun into nanofibers and characterized. A new laboratory based experimental apparatus for testing BFE was designed and used to test BFE of bacterial aerosols consisting of Escherichia coli (E. coli). Performances of soy protein based nanofiber filters with nanofiber mass varying from 1 to 5 g/m2 as well as a nanofiber filters prepared from pure PEO were compared. The results showed that BFE values for filters containing 5 g/m2 protein based nanofibers and PEO nanofiber filter were 100 and 81.5%, respectively. The results also indicated that the BFE increased as the protein content in the nanofiber filter increased. These novel protein based nanofiber filters have demonstrated a clear potential for effective removal and retention of E. coli bacteria during air-filtration. These filters can be effectively deployed in environments such as hospitals and senior residential areas to reduce bacterial infections.

Systematic review and meta-analysis of enhanced recovery programmes in surgical patients

BACKGROUND

Enhanced recovery programmes (ERPs) have been developed over the past 10 years to improve patient outcomes and to accelerate recovery after surgery. The existing literature focuses on specific specialties, mainly colorectal surgery. The aim of this review was to investigate whether the effect of ERPs on patient outcomes varies across surgical specialties or with the design of individual programmes.

METHODS

MEDLINE, Embase, CINAHL and the Cochrane Central Register of Controlled Trials were searched from inception to January 2013 for randomized or quasi-randomized trials comparing ERPs with standard care in adult elective surgical patients.

RESULTS

Thirty-eight trials were included in the review, with a total of 5099 participants. Study design and quality was poor. Meta-analyses showed that ERPs reduced the primary length of stay (standardized mean difference -1·14 (95 per cent confidence interval -1·45 to -0·85)) and reduced the risk of all complications within 30 days (risk ratio (RR) 0·71, 95 per cent c.i. 0·60 to 0·86). There was no evidence of a reduction in mortality (RR 0·69, 95 per cent c.i. 0·34 to 1·39), major complications (RR 0·95, 0·69 to 1·31) or readmission rates (RR 0·96, 0·59 to 1·58). The impact of ERPs was similar across specialties and there was no consistent evidence that elements included within ERPs affected patient outcomes.

CONCLUSION

ERPs are effective in reducing length of hospital stay and overall complication rates across surgical specialties. It was not possible to identify individual components that improved outcome. Qualitative synthesis may be more appropriate to investigate the determinants of success.

Behavioural response of wheat bulb fly (Delia coarctata, Diptera: Anthomyiidae) larvae to the primary plant metabolite carbon dioxide

Wheat bulb fly (WBF) larvae use chemotaxis to orientate towards host-plant root exudates. This study aimed to investigate the role of the primary plant metabolite carbon dioxide (CO2) in host-plant location by WBF. Arena based behavioural experiments were used to identify whether CO2 induced chemotaxis (directional movement in response to a chemical stimulus) or kinesis (non-directional movement in response to a stimulus) from WBF larvae. No chemotactic response was observed when larvae were presented to a point source of CO2. However, elevated levels of CO2 induced kinesis, with both track length and tortuosity (number of twists and turns in the movement path) increasing at elevated CO2 levels of 1000-2000 ppm, demonstrating increased searching behaviour. Soil emission of CO2 was quantified to compare soil levels with those identified as eliciting behavioural effects on the larvae. Samples removed from soil gave a mean CO2 concentration of 557 (±46) ppm, which is lower than the lowest concentration of CO2 found to induce a behavioural response and higher than the lowest CO2 concentration tested, which was found not to alter behaviour. It is proposed that increased CO2 concentrations in the soil act as a behavioural trigger, inducing intensive searching of an area by WBF larvae. This increases the likelihood of finding more host-specific identifiers, such as secondary metabolites when near a potential host-plant.

Diagnostic exercise: poor performance in a racehorse

A 9-year-old Thoroughbred gelding presented with a 97-day history of poor performance and intermittent fever. Clinicopathologic changes included increased serum activity of γ-glutamyltransferase and alkaline phosphatase, mild hyperbilirubinemia, and leukocytosis with neutrophilia and lymphopenia. Abdominal ultrasound revealed hepatomegaly with hyperechoic hepatic parenchyma and biliary distention. Pathologic findings included marked hepatomegaly (liver 3.6% of body weight), firm hepatic consistency with a diffuse enhanced reticular pattern, severe portal bridging and sinusoidal fibrosis, oval cell/bile duct hyperplasia, and bile stasis. The differential diagnoses and diagnostic workup to achieve the diagnosis are briefly discussed.