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Environmental DNA (eDNA) is a potentially powerful tool for detection and monitoring of rare species, including threatened native species and recently arrived invasive species. Here, we develop DNA primers for a suite of nine sympatric freshwater turtles, and use it to test whether turtle eDNA can be successfully detected in samples from aquaria and an outdoor pond. We also conduct a cost comparison between eDNA detection and detection through traditional survey methods, using data from field surveys at two sites in our target area. We find that eDNA from turtles can be detected using both conventional polymerase chain reaction (PCR) and quantitative PCR (qPCR), and that the cost of detection through traditional survey methods is 2-10X higher than eDNA detection for the species in our study range. We summarize necessary future steps for application of eDNA surveys to turtle monitoring and conservation and propose specific cases in which the application of eDNA could further the conservation of threatened turtle species.

Aleutian mink disease virus (AMDV) occurs in the American mink (Neovison vison) in wild populations and on mink farms and can cause illness and death. The North American river otter (Lontra canadensis) may be exposed to AMDV because of shared space and habitat with mink. Using serology and real-time PCR, we tested river otters across Ontario for AMDV infection. We found no evidence of infection in otters, a surprising finding given the sympatric distribution, niche overlap, and close phylogenetic relationship of the river otter and the American mink. Our results are consistent with the hypothesis that the major point of spillover of AMDV between mink farms and wildlife is manure and composting carcasses on mink farms. Mink farms in Ontario are generally in agricultural landscapes; it is unlikely that river otter use these habitats and thus are likely not exposed to AMDV. We found no evidence that AMD is an important disease for the river otters in Ontario.

Blood transfusions are frequently required following total knee arthroplasty. Tranexamic acid (TXA) inhibits fibrinolysis and has been shown to reduce blood loss and transfusion requirements when delivered intravenously. Topical and intra-articular applications directly target bleeding sites whilst limiting systemic uptake and theoretically reduce the risk of thromboembolic complications. However, in the absence of surgical drains, which increase post-operative blood loss, the efficacy of these techniques for reducing transfusion requirements is unclear. Our aim was to determine if locally administered tranexamic acid during total knee arthroplasty could reduce both blood loss and transfusion requirements in the absence of surgical drains. A retrospective review of 248 patients treated with primary unilateral cemented total knee arthroplasty was performed. Patients treated after January 2011 received topical and intra-articular tranexamic acid at the end of the procedure (n = 136). A second group of consecutive patients treated before this period acted as historical controls (n = 112). Patient groups were equivalent in terms of age, gender and ASA grade. There was a significant reduction in mean blood loss of 246 ml between the groups (p < 0.01). In addition, the requirement for post-operative allogenic blood transfusion was significantly reduced from 15.5 to 5.4 % after introduction of the tranexamic acid regimen (p = 0.02). This is the largest patient cohort reviewed to measure the efficacy of locally administered tranexamic acid during total knee arthroplasty and demonstrates that this is an effective technique for reducing both blood loss and transfusion requirements in the absence of surgical drains.

Sentinel species are important tools for studies of biodiversity and environmental health. The American mink (Neovison vison) has long been considered a sentinel of environmental contamination, since the species is known to be sensitive to a number of common contaminants, including polychlorinated biphenyls (PCB) and mercury. Mink may not always satisfy an important criterion of sentinels however--that they are continuous residents of the environment being sampled. This is because domestic mink commonly escape from farms, and can be confused with wild mink in areas where mink ranching is prevalent, biasing estimates of environmental contamination taken from free-ranging mink samples. We tested for bias in a sample of free-ranging mink from Ontario, Canada, where both genetic ancestry (domestic, wild, and domestic-wild hybrid) and contaminant burdens (PCBs and mercury) were known. Of 133 mink sampled for both contaminants and genetic ancestry, 9% were determined to be domestic and 10.5% hybrid animals. We found that including domestic and hybrid mink in our analysis resulted in overestimating mean PCB burdens in wild mink by 27%, and underestimating mercury by 13%. We also investigated morphological methods to aid in excluding domestic mink from free-ranging mink samples and found that we had the highest classification success using skull size (condylobasal length), which was 15% and 12% greater in male and female domestic than wild mink, respectively. Given the potential use of mink as sentinels, and also the potential for bias, we recommend that researchers take steps to exclude domestic mink from free-ranging mink samples in studies of environmental health., (Copyright © 2011 Elsevier Inc. All rights reserved.)

The release of domesticated organisms into natural populations may adversely affect these populations through predation, resource competition, and the introduction of disease. Additionally, the potential for hybridization between wild and domestic conspecifics is of great concern because it can alter the evolutionary integrity of the affected populations. Wild American mink (Neovison vison) populations may be threatened not only by competition for resources with domestic mink originating from farms, but by breeding with such escapees. Using 10 microsatellite loci, we genotyped mink from Ontario, Canada, sampled from two farms, two putatively mixed populations in regions surrounding the mink farms, and two wild populations with no recent history of mink farming. Using individual-based Bayesian population assignment, we identified four population clusters, including one wild, and three domestic populations. The latter were not clustered by farm but rather by distinct line-bred colour phases. Population clustering also identified domestic and hybrid mink in the free-ranging populations. Nearly two-thirds of the mink sampled in the two putatively mixed populations (78% and 43%) were either farm escapees or descendants of escapees. Principal components analysis of allele frequencies supported our Bayesian assignment results. The power of our assignment test was assessed using simulated hybrid genotypes which suggested that our overall correct classification rate was 96.2%. The overwhelming presence of domestic animals and their hybridization with mink in natural populations is of great concern for the future sustainability of wild mink populations.

We describe the isolation and characterization of 12 highly polymorphic microsatellite loci for the muskrat, Ondatra zibethicus. Microsatellite markers from three other rodent species were cross-amplified in muskrat and one of them was polymorphic. We observed moderate to high levels of genetic variability in these 13 polymorphic loci (five to 22 alleles per locus) with observed heterozygosity ranging from 0.48 to 0.96. These markers will be useful for further studies on population genetic structure in muskrat and potentially in other rodent species., (© 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.)

Fibronectins are widely expressed extracellular matrix ligands that are essential for many biological processes. Fibronectin-induced signaling pathways are elicited in diverse cell types when specific integrin receptors bind to the ninth and tenth FIII domains, FIII9-10. Integrin-mediated signal transduction involves activation of signaling pathways of the growth factor-dependent Ras-related small GTP-binding proteins Rho and Rac, and phosphorylation of focal adhesion kinase. We have dissected the requirement of FIII9 and FIII10 for Rho and Rac activity and phosphorylation of focal adhesion kinase in BHK fibroblasts and Swiss 3T3 cells. We demonstrate that FIII10 supports cell attachment but does not induce phosphorylation of focal adhesion kinase. In Swiss 3T3 cells, growth factor-independent phosphorylation of focal adhesion kinase and downstream adhesion events are dependent upon the presence of FIII9 in the intact FIII9-10 pair, whereas FIII10-mediated focal adhesion kinase phosphorylation requires a synergistic signal from growth factors. Furthermore, FIII10 is able to elicit cellular responses mediated by Rho, but not Rac, whereas FIII9-10 can elicit both Rho- and Rac-mediated responses. We propose that activation of specific integrin subunits by the FIII10 and FIII9-10 ligands elicits distinct signaling events. This may represent a general molecular mechanism for activation of receptor-specific signaling pathways by a multi-domain ligand.

As tetanus, a totally preventable disease, is still encountered in the older age group in England and Wales, a study was carried out to assess the state of immunity to the disease in the elderly population. These levels were compared to those in recruits and service personnel in the Army. Elderly patients with underlying disease had lower levels than the elderly who were healthy. When compared with recruit population the elderly group had significantly lower levels of antibody. If tetanus is to be eliminated, an effective programme of immunisation extending throughout life must be ensured.

Ketamine and midazolam were used for induction of anaesthesia and by continuous intravenous infusion for maintenance to assess their suitability for use in a total intravenous anaesthetic technique in the management of battle casualties. Muscular relaxation was provided by vecuronium and the patients' lungs ventilated with air. Ketamine was infused at a rate of 2 mg/kg/hour. This was achieved by mixing ketamine 200 mg, midazolam 5 mg and vecuronium 12 mg in 50 ml normal saline. The rate of infusion of the mixture (ml/hour) was then equal to 50% of the body weight in kg. The technique proved to be simple, effective and versatile and should be adaptable for use in the management of battle casualties.