Clinical Chemistry back issues from August 2007:
Medical and Economic Long-term Effects of B-Type Natriuretic Peptide Testing in Patients with Acute Dyspnea
Aug 01, 2007; ... Background: The objective of this prospective study was to assess the medical and economic long-term effects of using B-type natriuretic peptide (BNP) concentrations in the management of patients with acute dyspnea. Methods: We performed follow-up analysis of the B-Type Natriuretic ...
Vitamin C Deficiency and Scurvy Are Not Only a Dietary Problem but Are Codetermined by the Haptoglobin Polymorphism
Aug 01, 2007; ... Ascorbic acid (vitamin C) is prone to oxidation in vivo. The human plasma protein haptoglobin (Hp) shows a genetic polymorphism with 3 major phenotypes (Hp 1-1, Hp 2-1, and Hp 2-2) that show important functional differences. Despite an adequate nutritional supply, in Hp 2-2 individuals (most ...
Development of a Sensitive Real-Time Reverse Transcriptase PCR Assay with an Internal Control to Detect and Quantify Chikungunya Virus
Aug 01, 2007; ... Background: The Chikungunya virus (CHIKV; Alphavirus, Togaviridae) has emerged in the south Western Indian Ocean since early 2005. A major outbreak of CHIKV infection occurred in Réunion Island, where the virus is transmitted by Aedes albopictus mosquitoes. Facing an outbreak of unprecedented ...
Assessing Quality and Functionality of DNA from Fresh and Archival Dried Blood Spots and Recommendations for Quality Control Guidelines
Aug 01, 2007; ... Background: Dried blood spots (DBS) are a convenient and inexpensive method for biobanking. Although many countries have established population-based DBS biobanks from neonatal screening programs, the quality and usefulness of DNA from DBS have not been extensively assessed. Methods: We ...
Lipoprotein-Associated Phospholipase A^sub 2^ Predicts 5-Year Cardiac Mortality Independently of Established Risk Factors and Adds Prognostic Information in Patients with Low and Medium High-Sensitivity C-Reactive Protein (The Ludwigshafen Risk and Cardiovascular Health Study)
Aug 01, 2007; ... Background: Lipoprotein-associated phospholipase A^sub 2^ (LpPLA^sub 2^), also denoted as platelet-activating factor acetylhydrolase, is a lipoprotein-bound enzyme involved in inflammation and atherosclerosis. In this cohort study we investigated LpPLA^sub 2^ activity to predict cardiac ...
Quantitative Real-Time Reverse Transcription-PCR Study of the Expression of Vascular Endothelial Growth Factor (VEGF) Splice Variants and VEGF Receptors (VEGFR-1 and VEGFR-2) in Non-Small Cell Lung Cancer
Aug 01, 2007; ... Background: Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis and its expression is increased in non-small cell lung cancer (NSCLC). We aimed to determine the expression pattern of VEGF splice variants in NSCLC and its correlation with the clinico-pathological ...
Experimental Hyperhomocysteinemia Reduces Bone Quality in Rats
Aug 01, 2007; ... Background: Recently, hyperhomocysteinemia (HHCY) has been suggested as a new risk factor for osteoporosis. This study investigated if HHCY is a causal osteoporotic factor in vivo. Methods: We used 3 groups of rats: a control group (n = 20), a moderate HHCY group (induced by a 2.4% ...
Quantification of Hemoglobin A^sub 2^ by Tandem Mass Spectrometry
Aug 01, 2007; ... Background: Peptide-based analysis of whole blood using electrospray tandem mass spectrometry (MSMS) in multiple reaction monitoring (MRM) mode enables rapid detection and sequence confirmation of clinically significant hemoglobin (Hb) variants. We applied a similar, quantitative approach to the ...
Distribution of 15 Human Kallikreins in Tissues and Biological Fluids
Aug 01, 2007; ... Background: Kallikreins (KLKs) are a group of 15 secreted serine proteases. Some KLKs are established or candidate cancer biomarkers, but for most the physiological function is unknown. We characterized the protein and mRNA abundance patterns of all 15 KLKs in multiple panels of human tissues ...
An N-Terminal Molecular Form of Parathyroid Hormone (PTH) Distinct from hPTH(1-84) Is Overproduced in Parathyroid Carcinoma
Aug 01, 2007; ... Background: A new parathyroid hormone (PTH) species, the N-terminal PTH form (N-PTH), is distinct from intact human PTH of 84 amino acid residues [hPTH(184)] and is recognized in a 3rd-generation assay of "whole" PTH (wPTH; the 1-2 epitope) but not in a 2nd-generation assay of "total" PTH (tPTH; ...
Pilot Study for the Standardization of Insulin Immunoassays with Isotope Dilution-Liquid Chromatography/Tandem Mass Spectrometry
Aug 01, 2007; ... Background: An international working group convened by the American Diabetes Association (ADA) called for a reference measurement procedure for use in a trueness-based standardization project of insulin immunoassays. In view of this demand, we conducted a pilot study to investigate the ...
The Role of Adipocytokines in Insulin Resistance in Normal Pregnancy: Visfatin Concentrations in Early Pregnancy Predict Insulin Sensitivity
Aug 01, 2007; ... Background: Throughout pregnancy maternal adipose tissue is metabolically active, producing adipocytokines involved in the process of insulin resistance. We explored the role of serum adipocytokines, including the newly identified adipocytokine visfatin, in the process of insulin resistance in ...
Growth Hormone (GH) Receptor Isoform in Acromegaly: Lower Concentrations of GH but Not Insulin-Like Growth Factor-1 in Patients with a Genomic Deletion of Exon 3 in the GH Receptor Gene
Aug 01, 2007; ... Background: A genomic deletion of exon 3 (d3-GHR) of the growth hormone (GH) receptor (GHR) has been linked to the effectiveness of GH therapy in children with GH deficiency. Carriers of the d3-GHR genotype had higher GH-induced growth rates than children homozygous for the full-length (fl)-GHR ....
Simultaneous Analysis of D- and L-Serine in Cerebrospinal Fluid by Use of HPLC
Aug 01, 2007; ... Background: D-Serine is a coagonist for the glycine-binding site of the N-methyl-D-aspartate receptors and has been implicated in various neuropsychiatric functions such as learning, memory, and nociception, as well as schizophrenia and Alzheimer disease. We developed an HPLC method for D- and ...
A Disposable Multianalyte Electrochemical Immunosensor Array for Automated Simultaneous Determination of Tumor Markers
Aug 01, 2007; ... Background: Automated and convenient multianalyte detection with high throughput is increasingly needed in clinical diagnosis. We developed a disposable 4-by-2 array for programmed simultaneous amperometric immunoassay of 4 tumor markers. Methods: We used a screen-printed technique, ...
Multiple Fluorescent Labeling of Silica Nanoparticles with Lanthanide Chelates for Highly Sensitive Time-Resolved Immunofluorometric Assays
Aug 01, 2007; ... Background: Time-resolved immunofluorometric assays (TrIFA) using lanthanide-labeled nanoparticles have greatly increased the sensitivity of immunoassays. Current labeling strategies, however, use either physical doping of lanthanide chelates into preformed nanoparticles or covalent linking of ...
Impact of Renal Disease on Natriuretic Peptide Testing for Diagnosing Decompensated Heart Failure and Predicting Mortality
Aug 01, 2007; ... Background: Concomitant occurrence of kidney disease (KD) and heart failure (HF) is common and associated with poor outcomes. Natriuretic peptide studies have typically excluded many individuals with KD. We compared the accuracy of B-type natriuretic peptide (BNP) and N-terminal proBNP ...
Analytical and Diagnostic Characteristics of 11 2nd- and 3rd-Generation Immunoenzymatic Methods for the Detection of Antibodies to Citrullinated Proteins
Aug 01, 2007; ... Background: Measurement of antibodies to citrullinated peptides or proteins (CP) is a new test for the diagnosis of rheumatoid arthritis (RA). We analyzed the analytical characteristics and diagnostic accuracy of commercially available methods. Methods: We studied 11 commercially ...
Diagnostic Accuracy of Cervicovaginal Interleukin-6 and Interleukin-6:Albumin Ratio as Markers of Preterm Delivery
Aug 01, 2007; ... Background: Absence of fetal fibronectin (fFN) in the cervicovaginal fluid (CVF) of women with symptoms of preterm labor is an excellent predictor of women who will not deliver within 2 weeks of testing. Preliminary studies suggest interleukin (IL)-6 performs similarly to fFN. The positive ...
Apparent Loss of Urinary Albumin during Long-term Frozen Storage: HPLC vs Immunonephelometry
Aug 01, 2007; ... Background: Urinary albumin detection by immunonephelometry is decreased by ~30% in samples that have been frozen at -20 °C. An HPLC method for assessment of urinary albumin that detects immunoreactive and immunochemically nonreactive albumin has been introduced as an alternative to ...
Improved ELISA for Selective Measurement of Adiponectin Multimers and Identification of Adiponectin in Human Cerebrospinal Fluid
Aug 01, 2007; ... Background: Human serum adiponectin exists in 3 multimer forms: high molecular weight (HMW), middle molecular weight, and low molecular weight (LMW), with some of the latter bound to albumin (Alb)-LMW. Some studies have suggested that adiponectin crosses the blood-brain barrier and plays a ...
Expanded Instrument Comparison of Amplicon DNA Melting Analysis for Mutation Scanning and Genotyping
Aug 01, 2007; ... Background: Additional instruments have become available since instruments for DNA melting analysis of PCR products for genotyping and mutation scanning were compared. We assessed the performance of these new instruments for genotyping and scanning for mutations. Methods: A 110-bp ...
The Paradox in Translational Medicine
Aug 01, 2007; ... To the Editor: Advances in laboratory sciences have raised expectations of discovery of clinically useful biomarkers, but few such new tests have appeared to date. Hortin et al. (1) highlighted several challenges in the translation of promising markers into clinical laboratory tests ....
Analbuminemia Produced by a Novel Splicing Mutation
Aug 01, 2007; ... Analbuminemia is a rare autosomal recessive disorder manifested by the absence or severe reduction of circulating human serum albumin in homozygous or compound heterozygous individuals. It is an allelic heterogeneous defect, caused by a variety of mutations within the albumin gene. The ...
Primary Hyperoxaluria Remains Undiagnosed in Patients with Hyperoxaluria and Recurrent Urolithiasis
Aug 01, 2007; ... To the Editor: Primary hyperoxaluria (PH) is a metabolic disorder caused by deficiency of either the liver-specific enzyme alanine:gIyoxylate aminotransferase (AGT) for PH type 1 (PHl) or glyoxylate reductase/hydroxypyruvate dehydrogenase (GR/ HPR) for PH type 2 (PH2). PH increases ...
Quality Assessment of CoaguChek Point-of-Care International Normalized Ratio Monitors: A Note of Caution
Aug 01, 2007; ... To the Editor: In a recent publication Poller et al. (1) described quality assessment (QA) of CoaguChek (CUC) point-of-care (POC) international normalized ratio (INR) monitors and compared 2 procedures. The study compared the proportion of 523 CUC monitors having unsatisfactory ...
Serum and Plasma Cardiac Troponin I 99th Percentile Reference Values for 3 2nd-Generation Assays
Aug 01, 2007; ... To the Editor: Clinical and laboratory medicine associations have endorsed the implementation of the 99th percentile ref- erence value for cardiac troponin I (cTnl) and T (cTnT) for the detection of myocardial injury (1,2). In the presence of ischemia, cTn above the 99th percentile has ...
Interlaboratory Reproducibility of Isoelectric Focusing in Oligoclonal Band Detection
Aug 01, 2007; ... To the Editor: Current criteria for the diagnosis of multiple sclerosis (MS), an inflammatory neurological disease commonly affecting young adults, include cerebrospinal fluid (CSF) analysis to detect oligoclonal IgG bands (OCB) (1). CSF analysis methods vary substantially, however, and ...
Increased Human Chorionic Gonadotropin Due to Hypogonadism after Treatment of a Testicular Seminoma
Aug 01, 2007; ... To the Editor: Alfa-fetoprotein (AFP) and serum human chorionic gonadotropin (hCG) are reliable markers of testicular cancer, and treatment of a relapse is often initiated on the basis of marker increase alone. Slightly increased hCG concentrations have occasionally been misinterpreted ...
The Clinical Chemist
Aug 01, 2007; ... Clinical Chemistry Cited in Nearly 20 000 Articles during 2006 The newly released Journal Citation Reports (JCR) shows that Clinical Chemistry was cited 19 949 times during 2006 in articles published in the journals covered by JCR. This number of citations is an all-time high for the ...