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At least 19 recordsLinked to original sources
PubMed2026

Next-generation newborn screening: feasibility of combined genetic and biochemical testing for 95 treatable inherited metabolic disorders.

INTRODUCTION: Next-generation sequencing (NGS) is gaining attention in newborn screening (NBS) for its ability to detect treatable genetic disorders, especially those without a biochemical footprint. However, NGS-NBS requires interpreting variants without phenotype information or family trio analysis. Biochemical tests, preferably in dried blood spots (DBS), are therefore useful to confirm the pathogenicity of variants identified by NGS-NBS and increase its specificity and sensitivity. OBJECTIVES: We aimed to explore the potential of combined genetic-biochemical testing for 95 treatable Inherited Metabolic Disorders (IMD) considered eligible for NGS-NBS (100 genes) previously identified by our research group. METHODS: We reviewed the Collaborative Laboratory Integrated Reports (CLIR) and carried out systematic literature reviews in PubMed and Embase to identify biochemical tests for 95 IMD. Biochemical tests conducted on DBS were differentiated from tests that require referral. RESULTS: We identified DBS-biochemical tests for 72 of the 95 IMD (77/100 genes). DBS-based biochemical tests for 55 IMD (60 genes) are already implemented in NBS. For the other 23 IMD, biochemical tests in non-DBS specimens are reported, although some are less sensitive when measured at neonatal age in presymptomatic infants. CONCLUSION: We present a comprehensive overview of current biochemical tests for 95 IMD. These tests can be used to confirm inconclusive NGS-NBS results, and combined genetic-biochemical testing is expected to improve both the negative and positive predictive values of NBS programs.

Humans↗
PubMed2025

Biochemical testing for congenital disorders of glycosylation: A technical standard of the American College of Medical Genetics and Genomics (ACMG).

Congenital disorders of glycosylation (CDG) are a large and continually expanding group of disorders that present with a variety of clinical findings and have been linked to over 170 genes. Individually, CDGs are rare; however, the true incidence may be underestimated because of the variability of the clinical findings, and the multiple testing strategies needed to diagnosis them across multiple pathways. Testing for CDGs has evolved over recent years with the availability of high-throughput molecular testing and improved gene discovery techniques. Biochemical testing to detect defects in glycosylated proteins or enzymatic deficiency still plays a critical role in the diagnosis of affected individuals, and both testing modalities are often required to finalize a diagnosis. Emerging therapeutic approaches targeting improvements in glycosylation require reliable and reproducible biochemical testing for therapeutic monitoring, dose adjustment, and avoidance of dose-related side effects. To maintain clinical sensitivity and specificity and to ensure reproducibility across laboratories performing complex biochemical testing, the American College of Medical Genetics and Genomics has developed the following technical standard.

Humans↗
PubMed1978

Variation in metabolism of biochemical test substrates by Klebsiella species: an epidemiological tool.

The variation in metabolism of biochemical test substrates by klebsiella isolates has been demonstrated. It is suggested that this variation is likely to result in false-negative reactions in biochemical tests incubated for short periods. The observations made may explain the reported difficulties in obtaining reproducible results in biotyping Klebsiella strains. Preliminary work suggests that differences in substrate metabolism will provide a means of increasing the sensitivity of methods for the biochemical typing of Klebsiella spp.

Bacteriological Techniques↗
PubMedDate not supplied

Comparative studies of the strains PA and PN of Mycobacterium phlei leading to their reclassification: examination of lipids and DNA, biochemical tests and phage typing.

Study of lipid and DNA, biochemical tests and phage typing performed on the strain PA previously labelled Mycobacterium phlei, lead to the conclusion that this strain belongs to the species M. smegmatis. Parallel studies performed on strain PN, isolated from a culture of strain PA, as well as DNA homology percentage of the two strains, do not support the assumption that strain PN could have resulted from a mutation of strain PA Strain PN produces mycolic acids similar to those found in Rhodococcus bronchialis; the few biological tests applied quite agree with such a classification.

Bacteriophage Typing↗
PubMed1978

Comparison of a commercial identification kit and conventional biochemical tests used for the identification of enteric gram-negative rods.

A comparison between 11 Minitek biochemical tests and corresponding conventional tubed media was undertaken with 1,089 isolates of enteric gram-negative rods. Overall correlation between Minitek and conventional biochemicals was 97.4%. Minitek proved to be a time- and space-saving miniaturized biochemical system that can be used effectively for the identification of enteric gram-negative rods.

Bacteriological Techniques↗
PubMed1979

Biochemical testing for acute medical emergencies in four district general hospitals.

Comparable samples of 200 medical emergency admissions in four district general hospitals showed a threefold difference in the mean number of biochemical test values provided per patient, nearly all of which were obtained from blood specimens. Hospitals had consistently high or low mean numbers of values per patient for specific tests and clinical presentations and whether first or repeat tests were considered. Only 30 out of 188 different test types were reported at all four hospitals. Clinicians and chemical pathologists might benefit from regular expert advice on the most discriminating use of test information in cases with various clinical presentations.

Clinical Laboratory Techniques↗
PubMed1975

[The significance of lipoprotein X in the diagnosis of obstructive jaundice: comparison with other biochemical tests (author's transl)].

The reliability of lipoprotein-X demonstration in the diagnosis of obstructive jaundice was tested in 660 patients (1105 samples) and compared with other biochemical studies. Groups of 100 patients each with morphologically proven liver or biliary-tract disease were analyzed in order to determine the frequency with which the demonstration of lipoprotein X and biliary stasis coincided. There was no direct connection between hepatitis B antigen and lipoprotein X. Total cholesterol concentration provided no help in the differential diagnosis of jaundice, although in a series of cases with and without obstruction the mean concentrations differed significantly. Intra- and extrahepatic causes of jaundice and their aetiology could not be clarified merely by demonstrating the presence or absence of lipoprotein X. Nonetheless, it is a simple and safe method for proving biliary stasis.

Alanine Transaminase↗
PubMed1978

[Biochemical tests during measles].

In order to evaluate the role of measles in the development of vitamin A deficiency, biochemical parameters were compared in four groups of patients: a) 31 children in the first week of measles, b) 10 of these children who returned two weeks later, c) 9 patients hospitalized with other infections and d) 6 healthy controls. The average levels of serum iron, carotene, total proteins, albumin and beta-globulins did not differ significantly between these groups. However, during the first week of measles the following significant differences were found: a) an increase in alpha-2 and alpha-1-globulin levels (p less than 0,01), b) a decrease in gamma-globulin level (p less than 0,001), c) a decrease in vitamin A concentration (p less than 0,05) without clinical signs of deficiency. In the 10 patients who came again 2 weeks after the rash these parameters had returned toward control levels.

Female↗
PubMed1977

[Set of biochemical tests for studying the metabolic pathways of arginine and other basic amino acids in bacteria].

The author suggests a set of biochemical methods permitting to identify the enzymes participating in the utilization of arginine and some other amino acids. Use of the whole complex of the suggested tests permits to determine reliably the presence of one or another enzymatic activity. The described methods permitted quantitative recording and could be used both to ascertain the peculiarities of the amino acid metabolism in various bacterial species and possibly for the purpose of differential diagnosis and identification of bacteria.

Amino Acids↗
PubMed1977

[Checking the reliability of the PathoTec biochemical test system for bacterial identification].

Tests of the PathoTec system intended for express bacteriological diagnosis were checked in comparative experiments with the common biochemical methods. Cultures of the following microbes were used: Schigella, Salmonella, Escherichia, Citrobacter, Klebsiella, Enterobacter, Proteus, Providencia, Pseudomonas, Bordetella, Staphylococcus, Streptococcus. In a number of tests, such as determination of cytochromoxidase, nitrate reduciase, phenylalaninedeaminase, indol, acetoin (for the differentiation of enterobacteria), detection of plasmocoagulation and mannite fermentation (for staphylococci) there was revealed a complete coincidence of the results. However, discrepancies were revealed with three of the reagents tested (for lysine decarboxylase, urease, citrate utilization) with regard to some groups of enterobacteria. The advantages of the PathoTec system consisted in more rapid results, simplicity of procedures, economy of media and ware.

Bacteria↗
PubMed1978

The anomalous behaviour of dimethyl phosphates in the biochemical test for delayed neurotoxicity.

Several dimethyl phosphate behave anomalously in tests for delayed neurotoxicity. Doses given to hens caused high inhibition of brain neurotoxic esterase (NTE) but no ataxia. Less inhibition of NTE was seen in spinal cord than in brain. Di-isopropyl phosphorofluoridate caused equal inhibition of NTE in brain and cord. When dosing with dimethyl phosphates was repeated NTE inhibition in cord increased and pair-dosed birds became ataxic. In vitro brain and cord NTE were indistinguishable but the in vivo discrepancy between inhibition of brain and cord NTE was matched by a similar discrepancy in inhibition of AChE. It appears that ataxia arises from inhibition of spinal cord NTE and that only in the present cases (among about 200) was the effect in brain not a perfect biochemical monitor.

Animals↗
PubMed1978

Young Scientists Award Lecture 1977: An investigation into the value of some clinical biochemical tests in the detection of minimal changes in liver morphology and function in the rat.

Minimal liver damage was induced in groups of rats by the administration of three toxicants, viz. carbon tetrachloride, sodium phenobarbitone and orotic acid. Serial blood samples were taken from the animals during the course of the experiment and the plasma levels of a number of enzymes, substrates and metabolites were measured. Liver and kidney samples were also taken at appropriate times after dosing and examined histologically for evidence of drug induced damage. The results of the experiment show that (I) no single test gave unequivocal evidence of liver damage for all three compounds, (II) the conventional liver function tests, alanine transaminase, aspartate transaminase, and alkaline phosphatase, whose plasma activities are usually reported in toxicity studies, were not the most sensitive indicators of the minimal liver cell damage caused by the drugs used in this experiment, (III) knowledge of the intracellular location of the diagnostic enzyme makes it possible to describe, at least in part, the nature of the changes within the liver, (IV) measurement of plasma cholesterol and triglyceride levels can provide information about disruption in lipid metabolism, (V) the times at which blood samples are taken are most important if transient drug effects on the liver are to be detected.

Animals↗
PubMed1977

Rapid biochemical tests for characterization of the Mycoplasmatales.

Methods are described for the rapid detection of beta-D-glucosidase and phosphatase in mycoplasma cultures using fluorogenic 4-methylumbelliferone substrates. These methods were applied to a selection of mycoplasma cultures and were compared with the conventionally used tests for these enzymes. Results were similar by both methods, but the fluorogenic tests could be read after 1 h, whereas the conventional tests took several days.

Acholeplasma↗