Clinical Chemistry back issues from December 2006:
Serum Prealbumin: Is It a Marker of Nutritional Status or of Risk of Malnutrition?
Dec 01, 2006; ... Hospitalized patients who are undernourished are more likely to develop clinical complications and have relatively poor outcomes, with increased length of stay (LOS)1 and higher mortality compared with well-nourished patients. Provision of adequate nutritional support reduces the complication ...
Automatic Reporting of Estimated Glomerular Filtration Rate-Jumping the Gun?
Dec 01, 2006; ... In 2002, the Kidney Disease Outcomes Quality Initiative recommended the use of an estimated glomerular filtration rate (eGFR) to detect early kidney disease (1). Subsequently, the National Kidney Disease Education Program (NKDEP) has taken the lead in promoting the use of eGFR. In their ...
Will Epigenetic Allelic Ratio Analysis Turn Prenatal Diagnosis of Trisomy 18 on Its EAR?
Dec 01, 2006; ... In a proof of principle report elsewhere in this issue of Clinical Chemistry, Tong et al. (1) describe a novel approach to the noninvasive prenatal diagnosis of a human chromosomal abnormality by analyzing the allelic ratio of a polymorphism present within the methylated promoter of a DNA ...
Automatic Reporting of Estimated Glomerular Filtration Rate-Just What the Doctor Ordered
Dec 01, 2006; ... Chronic kidney disease (CKD) is a recently recognized public health problem. CKD is defined .is the presence of markers of kidney damage or of glomerular filtration rate (GFR) <60 mL-min^sup -1^ .(1.73 m^sup 2^)^sup -1^ [<1 mL . s^sup -1^ . (1.73 m^sup 2^)^sup -1^] for 3 months or more ...
Noninvasive Prenatal Detection of Fetal Trisomy 18 by Epigenetic Allelic Ratio Analysis in Maternal Plasma: Theoretical and Empirical Considerations
Dec 01, 2006; ... Background: The discovery of cell-free fetal DNA in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis. However, the use of maternal plasma fetal DNA for the direct detection of fetal chromosomal aneuploidies has not been reported. We postulate that the aneuploidy ...
Quantitative Assay of Deletion or Duplication Genotype by Capillary Electrophoresis System: Application in Prader-Willi Syndrome and Duchenne Muscular Dystrophy
Dec 01, 2006; ... Background: Deletions and duplications involving large DNA segments result in underexpression or overexpression, depending on the changes in allele dose, and are known to cause many common disorders. Detection of allele dose variations in the human genome is increasingly important in medical ...
Hypermethylated RASSF1A in Maternal Plasma: A Universal Fetal DNA Marker that Improves the Reliability of Noninvasive Prenatal Diagnosis
Dec 01, 2006; ... Background: We recently demonstrated that the promoter of the KASSF1A gene is hypermethylated in the placenta and hypomethylated in maternal blood cells. This methylation pattern allows the use of methylation-sensitive restriction enzyme digestion for detecting the placental-derived ...
Effect of Provider Continuity on Test Repetition
Dec 01, 2006; ... Background: Provider continuity (PC) occurs when a patient is treated by the same physician over time. A perceived benefit of PC is decreased test repetition. Repeat tests make up a significant proportion of overall laboratory utilization. This study determined whether test repetition increases ...
A Gray Zone Assigned to Inconclusive Results of Quantitative Diagnostic Tests: Application to the Use of Brain Natriuretic Peptide for Diagnosis of Heart Failure in Acute Dyspneic Patients
Dec 01, 2006; ... Background: Most quantitative diagnostic tests do not perfectly differentiate between persons with and without a given disease. We present a simple method to construct a 3-zone partition for quantitative tests results, including positive and negative zones and a gray zone between, and we ...
Sensitive Detection of KIT D816V in Patients with Mastocytosis
Dec 01, 2006; ... Background: The 2447 A>T pathogenic variation at codon 816 of exon 17 (D816V) in the KIT gene, occurring in systemic mastocytosis (SM), leads to constitutive activation of tyrosine kinase activity and confers resistance to the tyrosine kinase inhibitor imatinib mesylate. Thus detection of ...
Measurement of Fibrosis Marker Xylosyltransferase I Activity by HPLC Electrospray Ionization Tandem Mass Spectrometry
Dec 01, 2006; ... Background: Xylosyltransferase I (XT-I), the key enzyme in the biosynthesis of glycosaminoglycan chains in proteoglycans, has increased activity in the blood serum of patients with connective tissue diseases. Therefore, the measurement of serum XT-I activity is useful to monitor disease activity ...
Bound Homocysteine, Cysteine, and Cysteinylglycine Distribution between Albumin and Globulins
Dec 01, 2006; ... Background: Major portions of homocysteine (Hcy), cysteine (Cys), cysteinylglycine (CysGly), and glutathione in serum are covalently bound to proteins via disulfides. Albumin has been considered the dominant binding protein. Methods: Pooled serum and plasma from healthy adults were ...
Incorporation and Clearance of Omega-3 Fatty Acids in Erythrocyte Membranes and Plasma Phospholipids
Dec 01, 2006; ... Background: The sum of eicosapentaenoic acid (EPA, 20:5 ω3) and docosahexaenoic acid (DHA, 22:6 ω3) in erythrocyte membranes, termed the mnega-3 index, can indicate suboptimal intake of omega-3 fatty acids, a risk factor for cardiovascular disease (CVD). To study the effects of fatty ...
Rapid and Simultaneous Quantification of 4 Urinary Proteins by Piezoelectric Quartz Crystal Microbalance Immunosensor Array
Dec 01, 2006; ... Background: Urinary proteins are predictive and prognostic markers for diabetes nephropathy. Conventional methods for the quantification of urinary proteins, however, are time-consuming, and most require radioactive labeling. We designed a label-free piezoelectric quartz crystal microbalance ...
Prealbumin Serum Concentrations as a Useful Tool in the Assessment of Malnutrition in Hospitalized Patients
Dec 01, 2006; ... Background: Protein-energy malnutrition (PEM) is a common condition among patients admitted to hospitals, and it is associated with a worse prognosis and increased mortality. Although several screening systems have been developed, PEM is still poorly recognized, and there is no consensus on ...
Persistent Hypercalcemia After Parathyroidectomy in an Adolescent and Effect of Treatment With Cinacalcet HCl
Dec 01, 2006; ... Background: Hyperparathyroidism is uncommon in adolescence and is more likely to persist after parathyroidectomy than in adults. Cinacalcet HCl is a new calcimimetic that has been used successfully for the treatment of primary and secondary hyperparathyroidism in adults, but its use in ...
A Novel Real-Time Duplex PCR Assay for Detecting penA and ponA Genotypes in Neisseria gonorrhoeae: Comparison with Phenotypes Determined by the E-Test
Dec 01, 2006; ... Background: For many years, the pathogenic bacterium Neisseria gonorrhoeae, the etiologic agent of gonorrhea, was generally susceptible to penicillin, until the emergence of resistant strains. Well-characterized genetic variations in the penicillin resistance-determining region correlate with ...
Quantification of Urinary Oxalate by Liquid Chromatography-Tandem Mass Spectrometry with Online Weak Anion Exchange Chromatography
Dec 01, 2006; ... Background: Urinary oxalate is commonly measured with an enzymatic assay that is specific but requires a manual clean-up step to reduce ascorbic acid interference. We developed a urinary oxalate assay that uses liquid chromatography-tandem mass spectrometry (LC-MS/MS) with anion exchange ...
Improved Marker Combination for Detection of De Novo Genetic Variation and Aberrant DNA in Colorectal Neoplasia
Dec 01, 2006; ... Background: The genetic heterogeneity of sporadic colorectal cancer (CRC) makes the choice of genetic markers and sequence variation-detection technologies critical to the performance of screening assays. We have previously described the effectiveness of a CRC assay composed of 22 known variants ...
RNAprotect Saliva: An Optimal Room-Temperature Stabilization Reagent for the Salivary Transcriptome
Dec 01, 2006; ... To the Editor: Quantitative analysis can now be performed on a panel of human salivary mRNAs identified as potential markers for oral cancer (1, 2). Translational and clinical applications of salivary transcriptome diagnostics require RNA degradation in saliva to be stopped at the time ...
Measurement of 25-Hydroxyvitamin D Revisited/The authors of the article cited above respond
Dec 01, 2006; ... To the Editor: A notable shortcoming of the HPLC method for measuring 25-hydroxy-vitamin D described by Lensmeyer et al. (1) is its failure to adequately remove interference by the C3-epimer. Although the authors dismiss this because the interference was less than the lowest limit of ...
A Case of Pseudoparaproteinemia on Capillary Zone Electrophoresis Caused by Geloplasma
Dec 01, 2006; ... To the Editor: Capillary zone electrophoresis (CZR) df serum proteins is a well-accepted method used in clinical chemistry laboratories to separate serum proteins and detect monoclonal (M) protL'ins. The detection is based on ultraviolet absorbance measurements at 200 nm (Capillarys, ...
Size-Exclusion Chromatography of Circulating Cardiac Troponin T/The authors of the article cited above respond
Dec 01, 2006; ... To the Editor: In a recent issue of Clinical Chemistry, Fahie-Witson et al. (1) reported their use of gel-filtration chromatography and size-exclusion chromatography (SEC), combined with off-line measurement, to investigate circulating forms of cardiac troponin T (cTnT). We believe that ...
MALDI-TOF Mass Spectrometry Compared With Real-Time PCR for Detection of Fetal Cell-Free DNA in Maternal Plasma
Dec 01, 2006; ... To the Editor: Matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDl-TOF MS) has recently emerged as a new platform for highly sensitive and accurate analysis of DNA, especially cell-free DNA (cf-DN A) (1-3 ). In this context MALDI-TOF MS has been shown to ...
Further Evidence That the UGT1A1*28 Allele Is Not Associated with Coronary Heart Disease: The ECTIM Study
Dec 01, 2006; ... In their recent paper in Clinical Chemistry, Bosma et al. (1) were unable to demonstrate a protective effect of the UGT1A1*28 allele against coronary heart disease (CHD). This was surprising because individuals homozygous for the UGT1A1*28 altele have higher serum bilirubin than do heterozygous ...
Obituary: Alex Kaplan PhD (1910 - 2006)
Dec 01, 2006; ... Dr. Alex Kaplan, a past president of AACC and noted clinical chemist and educator, died in Seattle on July 2, 2000, at the age of 96. Besides his devotion to AACC, Dr. Kaplan, known affectionately to his friends, colleagues, and students as "Kap", is best noted for instituting the first Clinical ...
The Clinical Chemist
Dec 01, 2006; ... Position Statement The following was communicated to the editor from the Presidents of the American Association for Clinical Chemistry (AACC), American Diabetes Association (ADA), and European Association tor the Study of Diabetes (EASD): The boards of directors of the AACC, ADA, ...
Diagnosis of [alpha]-1-Antitrypsin Deficiency: An Algorithm of Quantification, Genotyping, and Phenotyping
Dec 01, 2006; ... Background: Laboratory testing in suspected α-1-antitrypsin (A1AT) deficiency involves analysis of A1AT concentrations and identification of specific alleles by genotyping or phenotyping. The purpose of this study was to define and evaluate a strategy that provides reliable laboratory ...
Efficient and Accurate Approaches to the Laboratory Diagnosis of [alpha]1-Antitrypsin Deficiency: The Promise of Early Diagnosis and Intervention
Dec 01, 2006; ... Abnormal human genes are rarely absolute predictors of the development of disease. With a few notable exceptions, abnormal genes predict risk of disease, and this risk is modified by environmental factors. When these environmental risk factors are known and minimised, early identification may ...
Pseudoparaproteinemia Related to Iomeprol Administration after Angiocardiography: Detection in the [beta] Fraction by Capillary Zone Electrophoresis
Dec 01, 2006; ... To the Editor: Analysis of serum proteins by capillary zone electrophoresis (CZE) has become a routine method for the detection of dysproteinemias and monoclonal proteins. Defection is based on ultraviolet absorbance at 200 nm (Capillarys, Sebia) or 214 nm (Paragon 2000, Beckman ...