Tracers In Metabolic Research

In the past few years, the number of applications of tracers for in vivo biomedical studies has greatly increased. New analytical tools at the genetic and protein levels have spurred this growth, opening the door for a deeper understanding of metabolic events. This in turn promises to yield significant advances in the understanding and treatment of human disease. Now fully revised and expanded, Isotope Tracers in Metabolic Research, Second Edition is the established definitive text on stable and radioactive isotope tracers. In unique, multidisciplinary fashion, it presents comprehensive coverage of new methodological, mathematical, and theoretical approaches. This new Second Edition includes: All-new chapters on nuclear magnetic resonance, mass isotopomer analysis, and methods of protein metabolism analysis A completely updated categorized list of over 750 references Major advances in the development of mass isotopomer and positional isotopomer techniques, noninvasive isotope techniques for studying metabolic pathways, hyphenated techniques, and new tracer techniques The latest developments in quantification of DNA synthesis and mass spectrometry spurred by genome sequencing and proteomics New coverage of mathematical modeling Expanded coverage of microdialysis probes, laboratory procedures, and regulatory issues related to human studies In this complete guide to performing tracer studies, the authors systematically cover tracer selection, modeling considerations, sample derivitization, mass spectrometry analysis, and data interpretation. Problems and discussion questions highlight key points in each chapter. Isotope Tracers in Metabolic Research, Second Edition offers students and researchers a comprehensive, practical resource for utilizing the latest tracer methodologies.

Methods for studying metabolism. Determination of substrate kinetics. Constant isotope infusion technique. Determination of substrate kinetics. Bolus-injection technique. Determination of substrate oxidation. Bicarbonate kinetics and natural enrichment. Priming the pool. Nonsteady state kinetics. Selection of sites for infusing isotope andj drawing samples. Specific application. Glucose metabolism. Specific application. Urea. Specific application. Fat meltabolism. Amino acids. Whole-body protein turnover. Total body water. Clinical application of stable isotopes. Analytical methods. Instrumentation. Mass spectrometry. Selected ion monitoring. Preparation of samples. Chromatography. Determination of specific radioactivity. Collection of CO2. Isotope ratio mass spectrometry techniques. Gas chromatography-mass spectrometry methods. In vivo approaches. Isotopic tracers. Advantages of stable isotopes. Biological effects. Enzymatic effects. Definition of terms. Influence of uptake on calculation of rate of appearance. Influence of pool size and complexity. Net movement of tracer and tracee. Clearance. Stable versus radioisotopes. Single-pool analysis. Bicarbonate recovery. Natural abundance of 13C. Practical consideration of performing recovery studies. Determining NaH13 CO3 infusion rate. Determining VCO2. Theory of priming dose. Priming secondary pools. Steele equation. In vivo assessment of steele equation. Glucose. Effective volume of distribution. Urea. Arterial versus central venous infusion.

The latest of a series of publications based on workshops sponsored by the Committee on Military Nutrition Research, this book's focus on emerging technologies for nutrition research arose from a concern among scientists at the U.S. Army Research Institute of Environmental Medicine that traditional nutrition research, using standard techniques, centered more on complex issues of the maintenance or enhancement of performance, and might not be sufficiently substantive either to measure changes in performance or to predict the effects on performance of stresses soldiers commonly experience in operational environments. The committee's task was to identify and evaluate new technologies to determine whether they could help resolve important issues in military nutrition research. The book contains the committee's summary and recommendations as well as individually authored chapters based on presentations at a 1995 workshop. Other chapters cover techniques of body composition assessment, tracer techniques for the study of metabolism, ambulatory techniques for the determination of energy expenditure, molecular and cellular approaches to nutrition, the assessment of immune function, and functional and behavioral measures of nutritional status.

The purpose of this monograph is to describe theoretical aspects of the interpretation of data obtained from experiments performed with labeled hormones. Quantitative endocrinologic studies involving the use of tracers include the determination of rates at which hormones are secreted by endocrine glands and are produced outside these glands by conversion of other secreted hor mones. Tracer experiments are also performed with the purpose of measuring rates of metabolic reactions. These measurements reveal the contribution of secreted hormones to the formation of circulating compounds and urinary metabolites. The estimation of rates of fetal and placental production and exchange of hormones characterizes a class of in vivo quantitative studies performed with isotopically labeled hormones (radioactive or not). In addi tion, tracers are used to measure permeability and rates of reaction in in vitro systems, and to study the uptake of hormones by tissues, both in vivo and in vitro. The stability of the steroid nucleus carrying the isotopic label and the large number of reversible metabolic reactions in which steroids are involved, both facilitated and motivated the development of a sophisticated theoretical treat ment of tracer experiments in the field of endocrinology. Although the prac tical examples used to illustrate the concepts and calculations presented in this monograph involve labeled hormones, the theory is presented in a general symbolic manner and is applicable to other fields of investigation.

An up-to-date, detailed, authoritative overview regarding all aspects of the theory and practice involved in utilizing isotopic tracers for the in vivo study of human metabolic function. Presents specific technical information on performing tracer studies including isotope infusion, analysis and interpretation of data.

1. Introduction. 2. Fundamentals of Tracer Kinetics. 3. The Noncompartmental Model of Multipool Systems. 4. The Compartmental Model. 5. Identifiability of the Tracer Model. 6. Using the Tracer Model to Estimate Kinetic Parameters. 7. Compartmental Versus Noncompartmental Kinetic Parameters. 8. Parameter Estimation: Some Fundamentals of Regression Analysis. 9. Parameter Estimation in Noncompartmental Models. 10. Parameter Estimation in Compartmental Models. 11. Precursor-Product Models. Appendices. Index.

This detailed volume focuses on recent technological, computational, and biostatistical advances in the field of high-throughput metabolomics. Chapters encompass methods, platforms, and analytical strategies for steady state measurements and metabolic flux analysis with stable isotope-labeled tracers, in biological matrices of clinical relevance and model organisms. Mass spectrometry-based or orthogonal methods are discussed, along with computational and statistical methods to address data sparsity in high-throughput metabolomics approaches. As a part of the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and practical, High-Throughput Metabolomics: Methods and Protocols provides tools that can bring about the next generation of clinical biochemistry in a cost-effective, rigorous fashion, exponentially advancing our capacity to investigate nature while hastening the advent of personalized medicine.