Abstract：
BACKGROUND:Plasma concentrations of small dense (sd)-LDL are associated with the prevalence of cardiovascular events. However, the special equipment and long assay times required for sd-LDL measurement have hindered its clinical application. Herein, we report development of a simple homogeneous assay for sd-LDL-cholesterol (C) adaptable to autoanalyzers. MATERIALS AND METHODS:We identified suitable surfactants and phospholipases by screening for those selective for the sd-LDL fraction (d 1.044-1.063 kg/L) and for the dissociation of other lipoproteins, including large buoyant LDL (lb-LDL). Principal characteristics of this assay were compared with ultracentrifugal isolation of LDL subfractions and with our previous heparin-magnesium precipitation assay for sd-LDL. We measured sd-LDL-C concentrations in 460 healthy, normolipidemic individuals. RESULTS:We used a polyoxyethylene benzylphenyl ether derivative to dissociate triglyceride-rich lipoproteins and HDLs, whereas sphingomyelinase proved most effective for dissociation of lb-LDL from LDL owing to the higher sphingomyelin content in the lb-LDL subfractions. A polyoxyethylene styrenephenyl ether derivative protected sd-LDL against the dissociative actions of sphingomyelinase and cholesterol oxidase/esterase during an initial incubation step. Next, polyoxyethylene alkyl ether dissociated sd-LDL-C and the cholesterol released from sd-LDL were subsequently measured by using cholesterol oxidase/esterase. The homogeneous method correlated excellently with ultracentrifugation for sd-LDL-C (y = 0.99x-0.09, R(2) = 0.91, n = 60) and exhibited within-run precision CVs <1.1%. The distribution of sd-LDL-C was skewed, and the central 95% of sd-LDL-C concentrations ranged from 0.24 to 0.88 mmol/L (9.4-34.0 mg/dL). CONCLUSIONS:The homogeneous assay allows reproducible measurement of sd-LDL-C within 10 min and appears promising in further investigations of the clinical significance of sd-LDL-C.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Ito Y,Fujimura M,Ohta M,Hirano Tdoi
10.1373/clinchem.2010.149559subject
Has Abstractpub_date
2011-01-01 00:00:00pages
57-65issue
1eissn
0009-9147issn
1530-8561pii
clinchem.2010.149559journal_volume
57pub_type
杂志文章abstract：:Patients' sera were analyzed for carbamazepine and ethosuximide by enzyme immunoassay (x) and gas chromatography (y), and the results were compared. The correlation coefficients were: for carbamazepine, x vs. y 0.94 (n = 93); for ethosuximide, x vs. y 0.99 (n = 30). These results suggest that the two methods could be ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-09-01 00:00:00
abstract：BACKGROUND:Quantitative PCR of viral nucleic acids can be useful clinically in diagnosis, risk assessment, and monitoring of antiviral therapy. We wished to develop a chemiluminescence competitive PCR (cPCR) for parvovirus B19. METHODS:Parvovirus DNA target sequences and competitor sequences were coamplified and direc...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
abstract：BACKGROUND:Unpredictable efficacy and toxicity are hallmarks of most anticancer therapies. Predictive markers are factors that are associated with response or resistance to a particular therapy. METHODS:The English literature relating to predictive markers in oncology was reviewed. Particular attention was paid to met...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2004.046227
更新日期：2005-03-01 00:00:00
abstract：:We evaluated a new EMIT II monoclonal amphetamine/methamphetamine assay for screening human urine by comparing it with the EMIT d.a.u. monoclonal amphetamine/methamphetamine assay and a fluorescence polarization assay. The EMIT II assay has a cutoff of 1 mg/L d-methamphetamine. The EMIT II and EMIT d.a.u. assays were ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-01-01 00:00:00
abstract：:We evaluated the Kallestad "Quanticoat" cortisol RIA for direct (no extraction) measurement of urinary free cortisol, which requires no solvent extraction. An analytical-recovery study showed a linear regression of y (measured) = 0.65x (added) + 37.5 micrograms/L (Sy.x = 21.4 micrograms/L, r = 0.978, n = 48). Recovery...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：:Analytical, intra-individual, and interindividual components of variation have been determined for pH, pCO2, bicarbonate, base excess, and total CO2 in capillary specimens of whole blood from a cohort of 14 healthy subjects. Calculated analytical goals (SD) are pH less than or equal to 0.008, pCO2 less than or equal t...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
abstract：:Direct-injection analysis for phenylalanine in plasma by isocratic "high-performance" liquid chromatography (HPLC) is described. For chromatographic separation I use an internal-surface reversed-phase silica support. The method involves ultraviolet detection, requires as little as 10 microL of plasma (routinely 20 mic...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-06-01 00:00:00
abstract：:Antiserum performance in a nephelometric system can be characterized by parameters derived from measuring reaction rates. The characterization process is derived from a series of dose-response curves (elicited nephelometric response vs antigen concentration) generated from various dilutions of the antiserum being test...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-11-01 00:00:00
abstract：:The clinical utilities of the emerging biochemical markers for mammary adenocarcinoma CA 15-3, CA 549, CA M26, CA M29, and MCA (mucin-like carcinoma-associated antigen) were assessed by a formal rating according to six desirable marker characteristics. All five indicators similarly have good specificities but limited ...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1993-11-01 00:00:00
abstract：:We describe a method for radioimmunoassay of conjugated cholic acid, chenodeoxycholic acid, and deoxycholic acid in serum. In the method, 125I-labeled bile acid conjugates are used as the tracers along with antibodies raised against individual bile acid-bovine serum albumin conjugates. Antibody-bound and free bile aci...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-02-01 00:00:00
abstract：:We present a simple method for subclass typing of IgG paraproteins, with which we have demonstrated a large number of paraproteins that were undetected by conventional immunofixation techniques. The types and distribution of IgG subclass paraproteins were analyzed in 92 human sera in which IgG paraproteins had been de...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-10-01 00:00:00
abstract：BACKGROUND:We sought to develop a tandem mass spectrometry assay in which the enzymatic activities of 3 lysosomal enzymes (α-glucosidase, α-galactosidase A, and α-l-iduronidase) could be quantified in dried blood spots by using a single assay buffer. METHODS:A 3-mm dried blood spot punch was incubated in a single assa...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.152009
更新日期：2010-12-01 00:00:00
abstract：:For 51 liver allograft recipients, we evaluated whether serum profiles of delta (Bd) and conjugated bilirubins (Bc) could be used to diagnose rejection during the first 30-50 postoperative days, in comparison with histology as the "gold standard." Daily measurements of aspartate aminotransferase, alkaline phosphatase,...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：:The Axial Separation Module (ASM), which separates whole-blood specimens serially in Axial Process Containers (APC), was evaluated for clinical performance at the University of Virginia Health Sciences Center (UVA HSC) in a community-based outpatient laboratory (North Ridge Clinic). We hypothesized that moving the tas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-02-01 00:00:00
abstract：BACKGROUND:The applicability of microarray-based transcriptome massive analysis is often limited by the need for large amounts of high-quality RNA. RNA arbitrarily primed PCR (RAP-PCR) is an unbiased fingerprinting PCR technique that reduces both the amount of initial material needed and the complexity of the transcrip...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.036236
更新日期：2005-01-01 00:00:00
abstract：:Zinc protoporphyrin is the predominent fluorescent porphyrin accumulating in erythrocytes as a result of chronic lead absorption or iron-deficiency anemia. Although diagnostic concentrations or thresholds for it in erythrocytes have been inferred, normal adult averages have not been established. We quantitatively asse...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-09-01 00:00:00
abstract：BACKGROUND:Adequate detection of designer steroids in the urine of athletes is still a challenge in doping control analysis and requires knowledge of steroid metabolism. In this study we investigated whether uPA(+/+)-SCID mice carrying functional primary human hepatocytes in their liver would provide a suitable alterna...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.119396
更新日期：2009-10-01 00:00:00
abstract：:Development of a new, sensitive immunoassay for measuring transforming growth factor beta 1 (TGF-beta1) is described and compared with four commercially available TGF-beta1 immunoassays. Preanalytical conditions were evaluated. The nonlinearity found in serum or plasma is due to masking of TGF-beta1 by binding protein...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1997-10-01 00:00:00
abstract：:The optimal measurement method and clinical application of the therapeutic drug monitoring of cyclosporine remain uncertain. At a workshop held at Hawk's Cay, FL, from January 14 to January 17, 1990, 57 scientists presented their latest research findings, either in formal papers or as discussants. Lively debate and di...
journal_title：Clinical chemistry
pub_type： 共识发展会议,杂志文章,评审
doi：
更新日期：1990-08-01 00:00:00
abstract：BACKGROUND:Genomic instability resulting in copy number variation is a hallmark of malignant transformation and may be identified through massive parallel sequencing. Tumor-specific cell free DNA (cfDNA) present in serum and plasma provides a real-time, easily accessible surrogate. METHODS:DNA was extracted from serum...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2014.226571
更新日期：2015-01-01 00:00:00
abstract：:We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-05-01 00:00:00
abstract：:In galactosemia, prevention of mental retardation depends on early recognition of the disorder and institution of dietary restriction of galactose. We describe an automated fluorometric micromethod for galactose in whole blood spotted on filter paper. Galactose is oxidized by galactose oxidase to D-galacto-hexadialdos...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-06-01 00:00:00
abstract：:Four assay procedures for tobramycin in serum--enzyme immunoassay (I), substrate-labeled fluorescent immunoassay (II), radioimmunoassay (III), and bioassay (IV)--were compared and evaluated by replicate and analytical recovery studies. I and II were about 50% more precise than III and IV. II was substantially more nea...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-01-01 00:00:00
abstract：BACKGROUND:Extracellular matrix alterations are important elements in the arterial changes seen in diabetes, being associated with increased vascular stiffness and the development of cardiovascular diseases. However, no biomarkers for diabetes-related arterial changes have been defined. METHODS:Mammary artery specimen...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.162966
更新日期：2011-11-01 00:00:00
abstract：BACKGROUND:Noninvasive prenatal diagnosis of monogenic disorders using maternal plasma and targeted massively parallel sequencing is being investigated actively. We previously demonstrated that comprehensive genetic diagnosis of a Duchenne muscular dystrophy (DMD) patient is feasible using a single targeted sequencing ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2014.236380
更新日期：2015-06-01 00:00:00
abstract：:Circadian variations of alanine aminopeptidase (EC 3.4.11.2), gamma-glutamyltransferase (EC 2.3.2.2), and N-acetyl-beta-glucosaminidase (EC 3.2.1.30) in urine were studied in 10 healthy children, ages six to 15 years. Urine specimens were collected during 24 h, grouped into four time intervals. Enzymes were measured s...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-05-01 00:00:00
abstract：BACKGROUND:Mucopolysaccharidosis type II (MPS II) is a lysosomal storage disorder related to a deficiency in the enzyme iduronate-2-sulfatase (IDS). Clinical trials of enzyme replacement therapy are in progress, but effective treatment will require screening assays to enable early detection and diagnosis of MPS II. Our...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2005.061838
更新日期：2006-04-01 00:00:00
abstract：:To evaluate their potential usefulness in the differential diagnosis of Cushing's syndrome, we estimated the urinary excretion rates of the following non-metabolized, unbound steroid hormones: pregnenolone, progesterone, 17-OH-pregnenolone, 17-OH-progesterone, dehydroepiandrosterone (DHEA), androstenedione, testostero...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
abstract：BACKGROUND:Vascular age is an emerging health indicator and predictor of end-organ damage to the heart, brain, and kidney. Although there have been many review publications concerning risk factors for vascular aging, most include cross-sectional epidemiological studies, limiting inferences about temporality. There is a...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2018.287623
更新日期：2019-01-01 00:00:00
abstract：:The manual Reference Method of the Centers for Disease Control for serum iron (CDC/RM/Fe) and a semiautomated adaptation of it were used to evaluate two working methods: one, a detergent solubilization procedure for the Roche Cobas-Bio analyzer, the other, the Kodak Ektachem 700 procedure, based on dry-film technology...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-10-01 00:00:00
