The Effects of Long-term Storage on Commonly Measured Serum Analyte Levels.

Background: Cohort studies typically bank biospecimens for many years before assay and investigators do not know whether levels of analytes have degraded.

Methods: We collected control samples from 22 nonstudy participants using the same enrollment criteria and specimen collection, processing, and storage protocols as The Sister Study. Serum samples were assayed for 21 analytes at collection and 6 years later.

A Biospecimen Proficiency Testing Program for Biobank Accreditation: Four Years of Experience.

Biobanks produce and distribute biospecimens, ensuring their fitness for purpose and accurately qualifying them before distribution. In their efforts toward professionalization, biobanks can nowadays seek certification or accreditation. One of the requirements of these standards is regular participation in Proficiency Testing (PT) programs.

Assays for Qualification and Quality Stratification of Clinical Biospecimens Used in Research: A Technical Report from the ISBER Biospecimen Science Working Group.

This technical report presents quality control (QC) assays that can be performed in order to qualify clinical biospecimens that have been biobanked for use in research. Some QC assays are specific to a disease area. Some QC assays are specific to a particular downstream analytical platform.

Repository Planning, Design, and Engineering: Part II-Equipment and Costing.

Part II of this article discusses and provides guidance on the equipment and systems necessary to operate a repository. The various types of storage equipment and monitoring and support systems are presented in detail. While the material focuses on the large repository, the requirements for a small-scale startup are also presented.

Repository Planning, Design, and Engineering: Part I--Infrastructure.

This is a two-part review describing the planning, engineering, and design considerations for building a new repository for biological and environmental samples. Part I addresses the physical infrastructure requirements for a repository; Part II will cover equipment and costing. Planning for construction of a new repository is a complex process requiring comprehensive preplanning and adherence to many regulatory and safety requirements.

Quality management of biorepositories.

Biomedical investigators require high quality human tissue to support their research; thus, an important aspect of the provision of tissues by biorepositories is the assurance of high quality and consistency of processing specimens. This is best accomplished by a quality management system (QMS). This article describes the basis of a QMS program designed to aid biorepositories that want to improve their operations.

Identification of evidence-based biospecimen quality-control tools: a report of the International Society for Biological and Environmental Repositories (ISBER) Biospecimen Science Working Group.

Control of biospecimen quality that is linked to processing is one of the goals of biospecimen science. Consensus is lacking, however, regarding optimal sample quality-control (QC) tools (ie, markers and assays). The aim of this review was to identify QC tools, both for fluid and solid-tissue samples, based on a comprehensive and critical literature review.

Standard preanalytical coding for biospecimens: review and implementation of the Sample PREanalytical Code (SPREC).

The first version of the Standard PREanalytical Code (SPREC) was developed in 2009 by the International Society for Biological and Environmental Repositories (ISBER) Biospecimen Science Working Group to facilitate documentation and communication of the most important preanalytical quality parameters of different types of biospecimens used for research. This same Working Group has now updated the SPREC to version 2.0, presented here, so that it contains more options to allow for recent technological developments.

Standard preanalytical coding for biospecimens: defining the sample PREanalytical code.

Background: Management and traceability of biospecimen preanalytical variations are necessary to provide effective and efficient interconnectivity and interoperability between Biobanks.

Methods: Therefore, the International Society for Biological and Environmental Repositories Biospecimen Science Working Group developed a "Standard PREanalytical Code" (SPREC) that identifies the main preanalytical factors of clinical fluid and solid biospecimens and their simple derivatives.

Results: The SPREC is easy to implement and can be integrated into Biobank quality management systems and databases.

Unexplained decline in the prevalence of anemia among US children and women between 1988-1994 and 1999-2002.

Background: The current anemia burden among US preschool children and women of childbearing age has not been documented.

Objective: We used data from National Health and Nutrition Examination Surveys 1988-1994 and 1999-2002 to examine recent anemia changes.

Design: We calculated the prevalence of anemia (hemoglobin < 11.

Homocysteine and vitamin B(12) concentrations and mortality rates in type 2 diabetes.

Objective: To assess the role of homocysteine as a risk factor for mortality in diabetic subjects.

Methods: Homocysteine, vitamin B(12), and folate concentrations were measured in stored sera of 396 diabetic Pima Indians aged > or = 40 years when examined between 1982 and 1985. Vital status was assessed through 2001.

Biochemical indicators of B vitamin status in the US population after folic acid fortification: results from the National Health and Nutrition Examination Survey 1999-2000.

Background: Mandatory folic acid fortification of cereal-grain products was introduced in the United States in 1998 to decrease the risk that women will have children with neural tube defects.

Objective: The objective was to determine the effect of folic acid fortification on concentrations of serum and red blood cell (RBC) folate, serum vitamin B-12, and plasma total homocysteine (tHcy) and methylmalonic acid (MMA) in the US population.

Design: Blood was collected from a nationally representative sample of approximately 7300 participants aged > or = 3 y in the National Health and Nutrition Examination Survey (NHANES) during 1999-2000 and was analyzed for these B vitamin-status indicators.

Hematological and iron-related analytes--reference data for persons aged 1 year and over: United States, 1988-94.

Objectives: This report presents national estimates of hematologic and iron-related analytes for persons 1 year of age and over, by age, sex, and race/ethnicity.

Methods: The analysis is based on data from the third National Health and Nutrition Examination Survey (NHANES III) (1988-94), which was designed to provide information on the health and nutritional status of the civilian noninstitutionalized U.S.

Selenium and colorectal adenoma: results of a pooled analysis.

Background: Secondary analyses of data from a large randomized clinical trial have suggested that intake of the trace element selenium reduces risk of colorectal neoplasia, but epidemiologic studies have not shown a consistent protective association.

Methods: We conducted a combined analysis of data from three randomized trials--the Wheat Bran Fiber Trial, the Polyp Prevention Trial, and the Polyp Prevention Study--which tested the effects of various nutritional interventions for colorectal adenoma prevention among participants who recently had an adenoma removed during colonoscopy. Selenium concentrations were measured from blood specimens from a total of 1763 trial participants, and quartiles of baseline selenium were established from the pooled data.

Prospective study of serum selenium concentrations and esophageal and gastric cardia cancer, heart disease, stroke, and total death.

Background: We previously reported an inverse association between prediagnostic serum selenium concentrations and the risk of esophageal squamous cell carcinoma (ESCC) and gastric cardia cancer (GCC) but not gastric noncardia cancer (GNCC) in a nested study from the Nutrition Intervention Trial in Linxian, China.

Objective: We examined the relation between baseline serum selenium and the subsequent risk of death from ESCC, GCC, GNCC, heart disease (HD), stroke, and total death over 15 y of follow-up (1986-2001).

Design: We measured baseline serum selenium concentrations in 1103 subjects randomly selected from a larger trial cohort.

Determination of folate vitamers in human serum by stable-isotope-dilution tandem mass spectrometry and comparison with radioassay and microbiologic assay.

Background: Current clinical methods for folate give different results and cannot measure the various forms of folate. We developed an isotope-dilution tandem mass spectrometric method coupled to liquid chromatography (LC/MS/MS) as a candidate reference method for 5-methyltetrahydrofolic acid (5MeTHF), 5-formyltetrahydrofolic acid (5FoTHF), and folic acid (FA) in human serum.

Methods: We quantitatively isolated folates from 275 microL of serum with a phenyl solid-phase extraction cartridge, then detected and quantified them in stabilized serum extracts by positive-ion electrospray ionization LC/MS/MS.

Prospective study of serum vitamin E levels and esophageal and gastric cancers.

Participants in the General Population Trial, a randomized nutrition intervention trial in Linxian, China, who received a combination of selenium, beta-carotene, and vitamin E supplements, had statistically significantly lower cancer mortality rates than those who did not receive the supplements. In the current study, we used a case-cohort design to examine the association between pre-trial serum vitamin E levels and the risks of developing esophageal and gastric cancers during the trial. We measured serum alpha- and gamma-tocopherol and cholesterol levels in 1072 case patients with incident esophageal squamous cell carcinoma (ESCC), gastric cardia cancer (GCC), or gastric noncardia cancer (GNCC) and in 1053 control subjects.

HFE genotype and transferrin saturation in the United States.

Purpose: Examine the penetrance (defined by high transferrin saturation [TS]) of C282Y and H63D in the U.S. population.

Erythrocyte protoporphyrin or hemoglobin: which is a better screening test for iron deficiency in children and women?

Background: Hemoglobin and erythrocyte protoporphyrin (EP) tests are commonly used to screen for iron deficiency. However, little research has been done to systematically evaluate the sensitivity and specificity of these 2 tests.

Objective: The objective of this study was to evaluate the sensitivity and specificity of hemoglobin and EP measurements in predicting iron deficiency in preschool children and in women of childbearing age.

Serum selenium levels in the US population: Third National Health and Nutrition Examination Survey, 1988-1994.

The published literature on serum selenium levels in the US population describes studies on small samples that may not be representative of the US population. This analysis provides the first nationally representative serum selenium levels in the US population by age group, sex, race-ethnicity, poverty income ratio (PIR), geographic region, and urban status. The Third National Health and Nutrition Examination Survey (NHANES III) is a national population-based cross-sectional survey with an in-person interview and serum selenium measurements.

Maternal serum B12 levels and risk for neural tube defects in a Texas-Mexico border population.

Purpose: Neural tube defects (NTDs) are common birth defects that can be prevented with folate fortification and supplementation. Studies suggest that other nutrients may also be essential to neural tube closure and have a potential role in risk reduction, with vitamin B(12) mentioned most often. We determined the effect of maternal serum B(12) levels, measured postpartum, on the risk of NTDs among a high risk Mexican American population.