Abstract：
BACKGROUND:Dopa-responsive dystonia (DRD) and tetrahydrobiopterin (BH4) defects are inherited disorders characterized by monoamine neurotransmitter deficiency with decreased activity of one of the BH4-metabolizing enzymes. The aim of the study was to determine the utility of cultured skin fibroblasts for the diagnosis of these diseases. METHODS:Neopterin and biopterin production and GTP cyclohydrolase I (GTPCH) activity were measured in cytokine-stimulated fibroblasts; 6-pyruvoyltetrahydropterin synthase (PTPS), sepiapterin reductase (SR), and dihydropteridine reductase (DHPR) activities were measured in unstimulated fibroblasts. We examined 8 patients with DRD, 3 with autosomal recessive GTPCH deficiency, 7 with PTPS deficiency, 3 with DHPR deficiency, and 49 controls (35 fibroblast and 14 amniocyte samples). RESULTS:Fibroblasts from patients with DRD and autosomal recessive GTPCH deficiency showed reduced GTPCH activity (15.4% and 30.7% of normal activity, respectively) compared with controls (P < 0.001). Neopterin production was very low and biopterin production was reduced in both disorders. PTPS- and DHPR-deficient cells showed no enzyme activities; in PTPS deficiency the pattern of pterin production was typical (neopterin, 334-734 pmol/mg; controls, 18-98 pmol/mg; biopterin, 0 pmol/mg; controls, 154-303 pmol/mg). Reference values of all enzyme activities and pterin production were measured in fibroblasts and also in amniocytes for prenatal diagnosis. CONCLUSIONS:Cultured skin fibroblasts are a useful tool in the diagnosis of BH4 deficiencies. Intracellular neopterin and biopterin concentrations and GTPCH activity in cytokine-stimulated fibroblasts are particularly helpful in diagnosing patients with DRD.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Bonafé L,Thöny B,Leimbacher W,Kierat L,Blau Nsubject
Has Abstractpub_date
2001-03-01 00:00:00pages
477-85issue
3eissn
0009-9147issn
1530-8561journal_volume
47pub_type
杂志文章abstract：BACKGROUND:Detection of melanoma cells in circulation may be important in assessing tumor progression. The objective of this study was to develop a specific, reliable multimarker quantitative real-time reverse transcription-PCR (qRT) assay for detecting melanoma cells in patients' blood. METHODS:We developed qRT assay...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.045096
更新日期：2005-06-01 00:00:00
abstract：:Measurement of the mass concentration of serum enzymes by radioimmunoassay provides direct quantitation of specific isoenzymes and may be less subject to some of the limitations of traditional assay procedures for enzymes. We describe the development of a sensitive and specific radioimmunoassay for the muscle isoenzym...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-03-01 00:00:00
abstract：:We determined the LD-1/LD-2 isoenzyme ratio in hemolysates of erythrocytes by electrophoresis on cellulose acetate and on agarose. A ratio exceeding 1.0 was found with the former but not the latter. Results were similar for in vitro models of hemolytic disorders. Using cellulose acetate electrophoresis, we determined ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-08-01 00:00:00
abstract：:Concentrations of free thyroxin (T4) and free triiodothyronine (T3) were measured in sera from pregnant women, in subjects with congenitally increased or decreased thyroxin-binding globulin (TBG), and in euthyroid controls. Measured free hormone concentrations were compared with calculated values for free hormone deri...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-08-01 00:00:00
abstract：:Gene probes can now be used to detect a variety of mutations that produce single-gene disorders. In present clinical practice, restriction endonuclease analysis is used for the prenatal diagnosis of sickle cell anemia, alpha-thalassemia, and beta-thalassemia. Direct detection of the mutation is possible in alpha-thala...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1985-09-01 00:00:00
abstract：:We describe a multiprobe colorimeter that permits the reading of enzyme-linked immunosorbent assays (ELISA) in situ, by use of microhemagglutination plates. The use of dipping probes eliminates interference from meniscus effects and air-bubble entrapment. Detailed validation tests have been done and potential sources ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-04-01 00:00:00
abstract：BACKGROUND:Until recently, clinical laboratories have monitored hemophilia treatment by measuring coagulation factors before/after infusion of human-derived or recombinant factors. Substantial changes are expected in the near future based on new therapeutic approaches that have been or are being developed. CONTENT:Hem...
journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：10.1373/clinchem.2017.284356
更新日期：2019-02-01 00:00:00
abstract：BACKGROUND:The liver is frequently subject to insult because of viral infection, alcohol abuse, or toxic chemical exposure. Extensive research has been conducted to identify blood markers that can better discern liver damage, but little progress has been achieved in clinical practice. Recently, circulating microRNAs (m...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2010.147850
更新日期：2010-12-01 00:00:00
abstract：:Values of low-density lipoprotein (LDL) cholesterol (C) according to the Friedewald formula (Clin Chem 1972;18:499-502) were compared with those obtained by lipoprotein fractionation in 98 healthy subjects (control group), 135 specimens from patients with peripheral vascular and cerebrovascular disease (atheroscleroti...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1991-08-01 00:00:00
abstract：:We have studied factors affecting biological variation in total plasma alkaline phosphatase in a population of 32 329 apparently healthy subjects four years old or older. Quantification of the bone and liver isoenzymes after thermal denaturation made it possible to specify the contributions of each isoenzyme to variat...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-04-01 00:00:00
abstract：:In this method for separating glycosylated from nonglycosylated hemoglobin in blood by electrophoresis on cellulose acetate membranes, we exploit the affinity of low-molecular-mass dextran sulfate for the nonglycosylated fraction, which increases the mobility of the latter relative to that of glycosylated hemoglobin. ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-02-01 00:00:00
abstract：BACKGROUND:The current diagnosis and monitoring of bladder cancer are heavily reliant on cystoscopy, an invasive and costly procedure. Previous efforts in urine-based detection of bladder cancer focused on targeted approaches that are predicated on the tumor expressing specific aberrations. We aimed to noninvasively de...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2018.301341
更新日期：2019-07-01 00:00:00
abstract：BACKGROUND:The discovery of cell-free fetal DNA in maternal plasma has opened up new possibilities for noninvasive prenatal diagnosis and monitoring. Among the fetal markers that have been described, methylation markers are sex and polymorphism independent. Methylation-sensitive restriction endonucleases are commonly u...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2007.092619
更新日期：2007-11-01 00:00:00
abstract：:Risk can lead to catastrophe. Risk-management systems are highly effective in preventing the catastrophes of fire, earthquakes, and work-site injuries. No such effective systems are present to prevent health and social problems. A practical, cost-effective system to manage risk in children is being developed by the no...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：:Consecutive values for serum osmolality measured in a patient exceeded (548 mOsm) the previously reported pathological range and, indeed, exceeded that generally considered compatible with life. The patient was receiving large amounts of intravenous dimethyl sulfoxide as part of an experimental protocol to control int...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-11-01 00:00:00
abstract：BACKGROUND:The determination of cellular beta-galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell-based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for beta-ga...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2008.115873
更新日期：2009-03-01 00:00:00
abstract：:A competitive solid-phase fluoroenzymeimmunoassay has been developed for rapidly measuring 5 beta-pregnane-3 alpha, 20 alpha-diol-3 alpha-glucuronide (Pd-3G) directly in diluted specimens of pre-breakfast urine. The assay involves use of an antiserum to Pd-3G and enzyme-labeled antigen prepared by chemically linking g...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-02-01 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：BACKGROUND:Although numerous lateral flow immunoassays (LFIAs) have been developed and widely used, inadequate analytical sensitivity and the lack of multiple protein detection applications have limited their clinical utility. We developed a new LFIA device for the simultaneous detection of high-sensitivity cardiac tro...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2011.171694
更新日期：2011-12-01 00:00:00
abstract：BACKGROUND:Methylmalonic acid (MMA) in plasma or serum is widely used for assessment of vitamin B(12) status. However, data are sparse regarding factors, besides renal function, that may influence MMA concentrations. We searched for important determinants of plasma MMA in the general population. METHODS:In 6946 middle...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2009.128678
更新日期：2009-12-01 00:00:00
abstract：:We describe a new multilayer immunoassay element for the determination of haptens in undiluted serum and plasma. Polysaccharide layers are coated onto a plastic base. The signal layer contains an immobilized antibody and a fluorescent-labeled hapten. A second layer, containing a pigment, acts as an optical screen. Sam...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
abstract：:Autocorrelation of clinical chemistry quality-control (Q/C) measurements causes one of the basic assumptions underlying the use of Levey-Jennings control charts to be violated and performance to be degraded. This is the requirement that the observations be statistically independent. We present a proposal for a new app...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：BACKGROUND:It has been postulated that changes in S-adenosylhomocysteine (AdoHcy), a potent inhibitor of transmethylation, provide a mechanism by which increased homocysteine causes its detrimental effects. We aimed to develop a rapid and sensitive method to measure AdoHcy and its precursor S-adenosylmethionine (AdoMet...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.046995
更新日期：2005-08-01 00:00:00
abstract：:In this method, leukocytes were isolated from 6 mL of EDTA-blood by density-gradient centrifugation and subsequently incubated with rhodamine isothiocyanate (RITC)-conjugated high-density lipoproteins (HDL). The receptor-bound conjugate particles were determined by fluorescent flow cytometry and compared with 125I-lab...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-12-01 00:00:00
abstract：BACKGROUND:In malignancy, gene mutations frequently occur in tumor suppressor genes such as p53 and are sporadically located. We describe a homogeneous method for amplification and mutation scanning, and apply the method to the p53 gene. METHODS:Using a series of overlapping fluorescein-labeled oligonucleotides comple...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2002-08-01 00:00:00
abstract：BACKGROUND:Increasing numbers of patients are presenting worldwide to emergency departments with suspected myocardial infarction. The use of point-of-care troponin assays might enable faster decision-making in this high-risk population and reduce the burden on emergency facilities. Here, we evaluate the diagnostic perf...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2019.307405
更新日期：2019-12-01 00:00:00
abstract：:Kappa Bence Jones proteinuria was found by immunoelectrophoretic techniques in a patient with plasma cell leukemia, who presented with no M-proteins either in serum or urine. However, a significant decrease in normal immunoglobulins was observed. On microscopic examination of kidney sections obtained a autopsy, protei...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-10-01 00:00:00
abstract：:Genetic engineering of beta-galactosidase (EC 3.2.1.23) has led to the development of a new homogeneous assay system, CEDIA. The Z gene of the lac operon of Escherichia coli encodes a large enzymatically inactive polypeptide that spontaneously aggregates and folds to form active beta-galactosidase. Using recombinant D...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-09-01 00:00:00
abstract：BACKGROUND:Several plasma proteins have been suggested as markers for a variety of cardiovascular conditions but fail to qualify in independent patient cohorts. This may relate to interference of medication on plasma protein concentrations. We used proteomics to identify plasma proteins that changed in concentration wi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2017.282665
更新日期：2018-10-01 00:00:00
abstract：BACKGROUND:Late enhancement MRI (LE-MRI) and cardiac troponin I (cTnI) are sensitive methods to detect subclinical myocardial injury. We sought to investigate the relation between plasma concentrations of cTnI measured with a high-sensitivity assay (hs-cTnI) and the development of unrecognized myocardial infarctions (U...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
doi：10.1373/clinchem.2014.222430
更新日期：2014-10-01 00:00:00
