Omega-3 long chain polyunsaturated fatty acid (n-3 LCPUFA) blood levels are a potential risk factor for coronary heart disease, particularly sudden cardiac death. Venipuncture sampling for fatty acid profiling is invasive, requires highly qualified personnel and requires a multi-step protocol to isolate blood fractions. Alternately, the use of whole blood for fatty acid profiling improves analytical throughput and allows sample collection in field research locations by enabling dried blood spotting (DBS). Dried blood spots are advantageous in comparison to venous blood sampling as they require small blood volumes and is relatively inexpensive to collect. However, FA profiles in DBS are commonly expressed qualitatively (% of total fatty acids) and not quantitatively ([mu]g/mL) as finger-tip prick (FTP) sampling usually results in the collection of an unknown volume of blood. Quantitation can be effected by preexisting fatty acid contaminants on DBS collection materials and oxidative losses of sensitive fatty acids such as n-3 LCPUFA due to the increased surface area of DBS samples. Fatty acid quantitation could detect hypo- and hyper-lipidemia in samples that a qualitative only assessments would miss. To address these issues, the relationship between blood volume and blood spot area on 903 Protein Saver Cards (903 PSC) was examined to determine the blood volume associated with a 6mm hole punch and the Mitra Microsampling Device, a product designed to collect 10 [mu]L of blood regardless of hematocrit, was assessed for FA and lipidomic analyses. To determine if fatty acid contaminants were present, the 903 PSC, the Mitra tips and Whatman chromatography paper (also commonly used to collect blood spots) were examined using gas chromatography and ultra high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). Finally, the stability of the fatty acids in a DBS sample on Mitra and 903 PSC stored at ambient, 4C, -20C and -80C temperatures with and without antioxidant for 3 months was examined. It was determined that the 6mm punch of 903 PSC contained 9.6 [mu]L of blood and that FA profiles determined from the Mitra samples were comparable to FA profiles from wet blood controls. The Mitra tips could also be used to provide similar lipidomic profiles. The 903 PSC, the Mitra tips and the Whatman paper all contained palmitic and stearic acid as free fatty acids (FFA) while the Mitra tips also had palmitoyl and stearoyl lysophosphatidylcholines (LysoPC) present. With DBS storage, the n-3 LCPUFA biomarkers were the most stable with -80C storage followed by 4C or ambient room temperatures while samples stored at -20C storage had the lowest stability in both antioxidant and no antioxidant conditions, which mirrored previous research examining whole blood storage. In conclusion, quantitative fatty acid determinations of DBS samples are possible. Blood volumes can be estimated using a defined hole punch on the commonly used 903 PSC, or defined by using a Mitra sampling device. Analysis of blank sampling devices is recommended to assess the potential impact of fatty acid and fatty acyl contaminants in any DBS collection materials to be used. Finally, storage conditions need to be a consideration with DBS sample collection as preventative steps such as storage temperature and the use of antioxidants can improve sample stability and ensure data integrity.

Increased consumption of n-3 long chain polyunsaturated fatty acids (LCPUFA) is associated with higher n-3 LCPUFA status in the circulation, which has in turn been associated with a number of health benefits in humans (Calder et al. 2006; Makrides et al. 2009; Einvik et al. 2010). The conventional approach to assay n-3 fatty acid status in humans involves invasive venous blood collection and expensive, time consuming multi-step processes as that limit its application in large-scare clinical trials and routine population screening (Riséet al. 2007). Recently, efforts have been made to adopt the dried blood spot (DBS) as a quick, inexpensive and minimally invasive alternative for the measurement of fatty acid status in humans (Marangoni et al. 2004). However, the existing DBS approaches have had only limited success in providing an accurate tool for the measurement of n-3 LCPUFA status in humans. This has been due to the presence of fatty acid contaminants in blood collection papers which are released during sample processing (Nishio et al. 1986; Ichihara et al. 2002),and the failure to prevent significant oxidative loss of the n-3 LCUFA in DBS sample during transportation and storage (Min et al. 2011; Bell et al. 2011). This thesis aimed to develop a novel DBS technique which would overcome these limitations and enable the technology to be used for the accurate evaluation of n-3 LCPUFA status in human subjects. Firstly, a wide range of potential collection matrices and lab consumables were tested to determine which contained the lowest contaminant levels. A range of antioxidants and chelating agents were then tested with DBS in order to identity the optimal combination of these factors for protecting the LCPUFA in DBS from oxidation. The protection system which provided optimal protection consisted of a combination of an antioxidant and a chelating agent applied to silica gel coated blood collection paper, and this resulted in more than 90% of the original n-3 LCPUFA content (expressed as a weight percentage in blood total lipids) in the DBS being retained following 2 months of storage at room temperature (20-25°C). This system (termed "PUFAcoat") represents a significant improvement in LCPUFA stability in DBS compared with previously reported standard DBS protection systems. For example, the standard Fluka system (Fluka blood collection kit) uses a single antioxidant (butylated hydroxytoluene, BHT) as protectant, and normal chromatography paper as a collection paper which retains only ~60% of the n-3 LCPUFA content in the applied DBS over the same time period (Min et al. 2011). To explore the mechanisms underlying the protective effect of the "PUFAcoat" and to improve my understanding of the processes causing the rapid breakdown of LCPUFA in DBS, a novel in vitro system (comprising an oil blend on collection paper) was developed. Using this model I established that iron-induced oxidation was the principle driver of the rapid loss of then-3 LCPUFA absorbed on the blood collection paper, and that iron chelating agent in the "PUFAcoat" system eliminated this process by binding the irons in the DBS samples. The clinical validity of the "PUFAcoat" system was established in a human study that compared the fatty acid spectrum obtained from my DBS method (using capillary blood) with those obtained by traditional analytical techniques (using venous blood fractions). This study demonstrated strong correlations in fatty acid status between my DBS method and conventional measurements, which indicate the potential of use of my DBS method as an appropriate alternative to conventional assessments. Morever, this clinical study showed that the n-3 LCPUFA status obtained using my DBS method reflected the habitual dietary n-3 fatty acid intakes of the study population. This thesis is the first report of a protection system that is capable of stabilising the n-3 LCPUFAs in human DBS samples over 2 months storage at room temperature. Thus, my newly developed DBS method offers a significant improvement in the useability and reliability of the DBS technique for assessing n-3 LCPUFA status in humans. My DBS method has significant potential for use in large-scale clinical testing and population based screening diagnostics which focused on the role of n-3 fatty acid status in human health.

An informative and comprehensive book on the applications and techniques of dried blood spot sampling Dried blood spot (DBS) sampling involves the collection of a small volume of blood, via a simple prick or other means, from a study subject onto a cellulose or polymer paper card, which is followed by drying and transfer to the laboratory for analysis. For many years, this method of blood sample collection has been extensively utilized in some important areas of human healthcare (for example, newborn screening for inherited metabolic disorders and HIV-related epidemiological studies). Because of its advantages over conventional blood, plasma, or serum sample collection, DBS sampling has been valued by the pharmaceutical industry in drug research and development. Dried Blood Spots: Applications and Techniques features contributions from an international team of leading scientists in the field. Their contributions present a unique resource on the history, principles, procedures, methodologies, applications, and emerging technologies related to DBS. Presented in three parts, the book thoroughly examines: Applications of DBS sampling and associated procedures and methodologies in various human healthcare studies Applications and perspectives of DBS sampling in drug research and development, and therapeutic drug monitoring New technologies and emerging applications related to DBS sampling and analysis Dried Blood Spots: Applications and Techniques is a valuable working guide for researchers, professionals, and students in healthcare, medical science, diagnostics, clinical chemistry, and pharmaceuticals, etc.

As clinical management of inherited metabolic diseases (IMDs) has improved, more patients affected by these conditions are surviving into adulthood. This trend, coupled with the widespread recognition that IMDs can present differently and for the first time during adulthood, makes the need for a working knowledge of these diseases more important than ever. Inherited Metabolic Disease in Adults offers an authoritative clinical guide to the adult manifestations of these challenging and myriad conditions. These include both the classic pediatric-onset conditions and a number of new diseases that can manifest at any age. It is the first book to give a clear and concise overview of how this group of conditions affects adult patients, a that topic will become a growing imperative for physicians across primary and specialized care.

Selected as a Doody's Core Title for 2022! Publisher's Note: Confidently interpret test results throughout your nursing curriculum, in clinicals, and in practice. Designed to accompany Brunner & Suddarth's Textbook for Medical-Surgical Nursing, 14th Edition, this concise, portable, full-color handbook gives you quick access to hundreds of test results and their implications for nursing. Easily review specimen collection procedures and access a concise, alphabetical list of nearly 300 tests and their implications. Find the information you need fast for each test: Reference values, critical values, and/or normal findings Abnormal findings with associated nursing implications Purpose and description Interfering factors Nursing considerations for patient care before, during, and/or after the tes Confidently address priority care issues and potentially hazardous or life-threatening situations with clearly identified best practices and warnings. Locate presentations of diseases, disorders, measurements, testing equipment, and examples of results at a glance in figures, tables, and boxes.