Rapid duplex immunoassay for wound biomarkers at the point-of-care

In this study we describe a novel method of sampling and quantifying wound biomarkers for clinical settings. We believe the chosen format will allow rapid assessments of wound healing and provide biomarker evidence-based decision points for treatment of the wound at the time of presentation. The wound monitoring principle uses a proprietary sample collection tool (a thermally reversible hydrogel) to sample and isolate biomarkers within a wound environment without further sample extraction/preparation steps. We show how gel samples can be analysed in a lateral flow assay format utilising fluorescent microspheres with optically discrete emission characteristics and demonstrate quantitative detection of two analytes (duplexing) achieved in a single test line. As a model assay, the chronic wound biomarkers interleukin 6 (IL6) and tumour necrosis factor alpha (TNFα) are used. Limits of detection of 48.5 pg/mL and 55.5 pg/mL respectively in hydrogel samples and 7.15 pg/mL and 10.7 pg/mL respectively in plasma are reported. We believe this is the first literature example of quantitative detection of multiple analytes within a single test line using spectral separation to distinguish the analytes.     

Effect of a conjugated linoleic acid and omega-3 fatty acid mixture on body composition and adiponectin

This study aimed to determine the effect of supplementation with conjugated linoleic acids (CLAs) plus n-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFAs) on body composition, adiposity, and hormone levels in young and older, lean and obese men. Young (31.4+/-3.9 years) lean (BMI, 23.6+/-1.5 kg/m2; n=13) and obese (BMI, 32.4+/-1.9 kg/m2; n=12) and older (56.5+/-4.6 years) lean (BMI, 23.6+/-1.5 kg/m2; n=20) and obese (BMI, 32.0+/-1.6 kg/m2; n=14) men participated in a double-blind placebo-controlled, randomized crossover study. Subjects received either 6 g/day control fat or 3 g/day CLA (50:50 cis-9, trans-11:trans-10, cis-12) and 3 g/day n-3 LC-PUFA for 12 weeks with a 12-week wash-out period between crossovers. Body composition was assessed by dual-energy X-ray absorptiometry. Fasting adiponectin, leptin, glucose, and insulin concentrations were measured and insulin resistance estimated by homeostasis model assessment for insulin resistance (HOMA-IR). In the younger obese subjects, CLA plus n-3 LC-PUFA supplementation compared with control fat did not result in increased abdominal fat and raised both fat-free mass (2.4%) and adiponectin levels (12%). CLA plus n-3 LC-PUFA showed no significant effects on HOMA-IR in any group but did increase fasting glucose in older obese subjects. In summary, supplementation with CLA plus n-3 LC-PUFA prevents increased abdominal fat mass and raises fat-free mass and adiponectin levels in younger obese individuals without deleteriously affecting insulin sensitivity, whereas these parameters in young and older lean and older obese individuals were unaffected, apart from increased fasting glucose in older obese men.     

Variable responses of tuber moth to the leaf trichomes of wild potatoes

This study examines the response of tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae), during the initial stages of attack, to variability in trichome density and composition on foliage of Solanum berthaultii (Hawkes) and Solanum tarijense (Hawkes) (Solanaceae). Solanum berthaultii bears two types of glandular trichome (type A and type B) that together reduced oviposition by the moth. Females were often completely deterred from ovipositing on foliage with >300 trichomes per cm². In contrast, neonate establishment on S. berthaultii was generally positively related to trichome densities, indicating that trichomes may be a poor defense against P. operculella when the moth oviposits in soil and neonate larvae select the host plant. Solanum tarijense has only one type of glandular trichome (type A) and eglandular hairs. Most eggs were deposited on the adaxial leaf surfaces that had lower trichome densities. Although the density of type A trichomes was negatively related to oviposition, high densities of hairs on the abaxial and adaxial leaf surfaces appeared to stimulate oviposition, leading to stronger positive relations between hair densities and oviposition. Larvae generally established on the abaxial surface where hair densities were greatest. Relationships between the abaxial densities of leaf hairs and neonate establishment on S. tarijense were positive. The results indicate that the responses by P. operculella to the types and density of trichomes are complex. Whereas type A and type B trichomes may act synergistically to reduce oviposition by the moth, leaf hairs do not defend against oviposition and neither leaf hairs nor type A and B trichomes reduce neonate establishment by this herbivore species.     

Isolation of identical nitrilase genes from multiple bacterial strains and real-time PCR detection of the genes from soils provides evidence of horizontal gene transfer

Bacterial enzymes capable of nitrile hydrolysis have significant industrial potential. Microbacterium sp. AJ115, Rhodococcus erythropolis AJ270 and AJ300 were isolated from the same location in England and harbour identical nitrile hydratase/amidase gene clusters. Strain AJ270 has been well studied due to its nitrile hydratase and amidase activity. R. erythropolis ITCBP was isolated from Denmark and carries a very similar nitrile hydratase/amidase gene cluster. In this study, an identical nitrilase gene (nit1) was isolated from the four strains, and the nitrilase from strain AJ270 cloned and expressed in Escherichia coli. Analysis of the recombinant nitrilase has shown it to be functional with activity demonstrated towards phenylacetonitrile. A real-time PCR TaqMan^® assay was developed that allowed nit1 detection directly from soil enrichment cultures without DNA extraction, with nit1 detected in all samples tested. Real-time PCR screening of isolates from these soils resulted in the isolation of nit1 and also very similar nitrilase gene nit2 from a number of Burkholderia sp. The genes nit1 and nit2 have also been detected in many bacteria of different genera but are unstable in these isolates. It is likely that the genes were acquired by horizontal gene transfer and may be widespread in the environment.     

Ecology and conservation of insectivorous bats in fragmented areas of macadamia production in eastern Australia

Microbats perform important ecological services in agro‐ecosystems, but several species are globally threatened by loss of roosting and breeding habitats. The successful conservation of bats in agricultural land requires adequate knowledge of their ecology. Using ultrasonic recorders, we studied the activity of insectivorous bats in areas of macadamia production in eastern Australia at two spatial scales: across woodland‐orchard transects at the local scale and across three levels of fragmentation at the landscape scale. At the local scale, activity patterns of ‘clutter’ and ‘edge’ specialists were consistently higher in woodland patches, gradually decreasing towards isolated orchards, where only a few ‘open’ specialists were active. At the landscape scale, bat community activity was affected by the level of fragmentation, partly because three of the most recorded taxa (Austronomus australis, Saccolaimus flaviventris and Miniopterus australis) had their highest activity in less‐fragmented areas. A distance‐based model explained 24% of the bat community activity based on a combination of six environmental variables. Canonical correspondence analysis showed that a number of bat taxa were associated with open areas of macadamia, whereas other taxa were associated with increasing values of landscape composition, and arthropod and water availability. In addition, total bat activity was highly correlated with foraging rate. These results suggest that most bat taxa were influenced by proximity to woodland and the degree of fragmentation, and only few taxa were able to exploit isolated orchards. Environmental factors that promote bat activity could be exploited to strengthen conservation efforts. Preserving remnant woodland and promoting habitat heterogeneity will benefit several bat species. In particular, the foraging activity of ‘edge’ specialists could be fostered by increasing landscape connectivity and maintaining unobstructed water bodies near macadamia orchards. Considering that bats forage as they navigate these areas, conservation efforts could also bring benefits to farmers through pest‐reduction services.     

Effect of dietary supplementation with a Saccharomyces cerevisiae mannan oligosaccharide on the bacterial community structure of broiler cecal contents

This study investigated the effects of dietary supplementation with a prebiotic mannan oligosaccharide (MOS) on broiler performance, bacterial community structure, and phylogenetic populations of cecal contents. Bird performance data were collected, and cecal samples were extracted from randomly caught poults from each treatment group every 7 days from hatching to the age of 42 days. Weight gain, feed consumption, and feed efficiency ratios did not differ significantly between groups. Automated ribosomal intergenic spacer analysis (ARISA) of the bacterial communities in birds receiving MOS-supplemented diets indicated that dietary supplementation with MOS at either of 2 levels significantly altered the bacterial community structure from that of the control group on all sample days. The phylogenetic identities of bacteria contained within the cecum were determined by constructing a 16S rRNA gene clone library. A total of 594 partial 16S rRNA gene sequences from the cecal contents were analyzed and compared for the three dietary treatments. The dominant bacteria of the cecum belonged to three phyla, Firmicutes, Bacteroidetes, and Proteobacteria; of these, Firmicutes were the most dominant in all treatment groups. Statistical analysis of the bacterial 16S rRNA gene clone libraries showed that the compositions of the clone libraries from broilers receiving MOS-supplemented diets were, in most cases, significantly different from that of the control group. It can be concluded that in this trial MOS supplementation significantly altered the cecal bacterial community structure.