55 research outputs found
Suitability of Dried Blood Spots for Accelerating Veterinary Biobank Collections and Identifying Metabolomics Biomarkers With Minimal Resources
Biomarker discovery using biobank samples collected from veterinary clinics would deliver insights into the diverse population of pets and accelerate diagnostic development. The acquisition, preparation, processing, and storage of biofluid samples in sufficient volumes and at a quality suitable for later analysis with most suitable discovery methods remain challenging. Metabolomics analysis is a valuable approach to detect health/disease phenotypes. Pre-processing changes during preparation of plasma/serum samples may induce variability that may be overcome using dried blood spots (DBSs). We report a proof of principle study by metabolite fingerprinting applying UHPLC-MS of plasma and DBSs acquired from healthy adult dogs and cats (age range 1-9 years), representing each of 4 dog breeds (Labrador retriever, Beagle, Petit Basset Griffon Vendeen, and Norfolk terrier) and the British domestic shorthair cat (n = 10 per group). Blood samples (20 and 40 μL) for DBSs were loaded onto filter paper, air-dried at room temperature (3 h), and sealed and stored (4°C for ~72 h) prior to storage at -80°C. Plasma from the same blood draw (250 μL) was prepared and stored at -80°C within 1 h of sampling. Metabolite fingerprinting of the DBSs and plasma produced similar numbers of metabolite features that had similar abilities to discriminate between biological classes and correctly assign blinded samples. These provide evidence that DBSs, sampled in a manner amenable to application in in-clinic/in-field processing, are a suitable sample for biomarker discovery using UHPLC-MS metabolomics. Further, given appropriate owner consent, the volumes tested (20-40 μL) make the acquisition of remnant blood from blood samples drawn for other reasons available for biobanking and other research activities. Together, this makes possible large-scale biobanking of veterinary samples, gaining sufficient material sooner and enabling quicker identification of biomarkers of interest
Effects of Mindfulness-Based Cognitive Therapy on Specificity of Life Goals
This study explored the immediate effects of a course of Mindfulness-Based Cognitive Therapy (MBCT) for chronically depressed participants with a history of suicidality on the specificity of important goals for the future. Participants were randomly allocated to immediate treatment with MBCT or to a waitlist condition and life goals were assessed both before and after the treatment or waiting period. Results showed that participants receiving MBCT reported significantly more specific goals post-treatment whereas those allocated to the waitlist condition showed no significant change. Similarly, participants allocated to MBCT regarded themselves as significantly more likely to achieve their important goals post-treatment, whilst again there was no significant change in the waitlist group. Increases in goal specificity were associated with parallel increases in autobiographical memory specificity whereas increases in goal likelihood were associated with reductions in depressed mood. These results suggest that MBCT may enable participants to clarify their important goals and in doing so increase their confidence in their capacity to move in valued life directions
AKT1 Loss Correlates with Episomal HPV16 in Vulval Intraepithelial Neoplasia
Anogenital malignancy has a significant association with high-risk mucosal alpha-human papillomaviruses (alpha-PV), particularly HPV 16 and 18 whereas extragenital SCC has been linked to the presence of cutaneous beta and gamma–HPV types. Vulval skin may be colonised by both mucosal and cutaneous (beta-, mu-, nu- and gamma-) PV types, but there are few systematic studies investigating their presence and their relative contributions to vulval malignancy. Dysregulation of AKT, a serine/threonine kinase, plays a significant role in several cancers. Mucosal HPV types can increase AKT phosphorylation and activity whereas cutaneous HPV types down-regulate AKT1 expression, probably to weaken the cornified envelope to promote viral release. We assessed the presence of mucosal and cutaneous HPV in vulval malignancy and its relationship to AKT1 expression in order to establish the corresponding HPV and AKT1 profile of normal vulval skin, vulval intraepithelial neoplasia (VIN) and vulval squamous cell carcinoma (vSCC). We show that HPV16 is the principle HPV type present in VIN, there were few detectable beta types present and AKT1 loss was not associated with the presence of these cutaneous HPV. We show that HPV16 early gene expression reduced AKT1 expression in transgenic mouse epidermis. AKT1 loss in our VIN cohort correlated with presence of high copy number, episomal HPV16. Maintained AKT1 expression correlated with low copy number, an increased frequency of integration and increased HPV16E7 expression, a finding we replicated in another untyped cohort of vSCC. Since expression of E7 reflects tumour progression, these findings suggest that AKT1 loss associated with episomal HPV16 may have positive prognostic implications in vulval malignancy
Comparison of diffuse-reflectance absorbance and attenuated total reflectance FT-IR for the discrimination of bacteria
A collection of bacteria belonging to the genus Bacillus were analysed by diffuse reflectance absorbance and attenuated total reflectance Fourier transform infrared (FT-IR) spectroscopy in the mid-infrared. The diffuse reflectance absorbance method is a rapid whole organism fingerprinting method, which generates a biochemical profile of the bacteria, where samples are presented to the FT-IR spectrometer dried on a metal carrier. The attenuated total reflectance FT-IR used in conjunction with a diamond attenuated total reflectance (ATR) accessory produces a biochemical profile of the surface chemistry of bacteria directly without the need for drying, and has not previously been used in the discrimination of bacteria. Principal component, discriminant function and hierarchical cluster analysis were performed on the data to discriminate the bacteria. The differentiation of the bacteria to species level was observed in both analyses however, it was concluded that the ATR FT-IR illustrated better sub-species differentiation of the microorganisms. This may imply that the total biochemical profiling infers discrimination to species level whereas strain specific markers are present on the cell surface chemistry. DOI: 10.1039/b408169
Raman spectroscopy: Lighting up the future of microbial identification
Over the last decade Raman spectroscopy has become established as a physicochemical technique for the rapid identification of microbes. This powerful analytical method generates a spectroscopic fingerprint from the microbial sample, which provides quantitative and qualitative information that can be used to characterize, discriminate and identify microorganisms, in both bacteria slurry and at the single-cell level. Recent developments in Raman spectroscopy have dramatically increased in recent years due to the enhancement of the signal by techniques including tip-enhanced Raman spectroscopy and coherent anti-Stokes Raman spectroscopy and due to the availability of user-friendly instrumentation and software. The result of this has been reduced cost and rapid collection time, and it has allowed the nonspecialist access to this physical sciences approach for biological applications. In this article, we will briefly explain the technique of Raman spectroscopy and discuss enhancement techniques, including the recent application of tip-enhanced Raman spectroscopy to microbiology, as well as the move towards rapid microbial identification with Raman spectroscopy. Furthermore, recent studies have combined Raman spectroscopy with microfluidic devices, giving greater control of sample conditions, which will no doubt have an important impact in the future development of Raman spectroscopy for microbial identification
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