ABSTRACT
BACKGROUND: Tandem mass spectrometry (MS MS) and simple fluorometric assays are currently used in newborn screening programs to detect inborn errors of metabolism (IEM). The aim of the study was to evaluate the clinical utility of exome sequencing as a second tier screening method to assist clinical diagnosis of the newborn. METHODS: A novel PCR-exome amplification and re-sequencing (PEARS) assay was designed and used to detect mutations in 122 genes associated with 101 IEM. Newborn bloodspots positive by biochemical testing were analysed by PEARS assay to detect pathogenic mutations relevant to the IEM. RESULTS: In initial validation studies of genomic DNA samples, PEARS assay correctly detected 25 known mutations associated with 17 different IEM. Retrospective gene analysis of newborns with clinical phenylketonuria (PKU), identified compound heterozygote phenylalanine hydroxylase (PAH) gene mutations in eight of nine samples (89%). Prospective analysis of 211 bloodspots correctly identified the two true PKU samples, yielding positive and negative predictive values of 100%. Testing of 8 true positive MS MS samples correctly identified potentially pathogenic compound heterozygote genotypes in 2 cases of citrullinemia type 1 and one case each of methylmalonic acidemia, isobutyryl-CoA dehydrogenase deficiency, short chain acyl-CoA dehydrogenase deficiency and glutaric acid type II and heterozygous genotypes in 2 cases of autosomal dominant methioninemia. Analysis of 11 of 12 false positive MS MS samples for other IEM identified heterozygous carriers in 8 cases for the relevant genes associated with the suspected IEM. In the remaining 3 cases, the test revealed compound heterozygote mutations in other metabolic genes not associated with the suspected IEM, indicating a misinterpretation of the original MS MS data. CONCLUSIONS: The PEARS assay has clinical utility as a rapid and cost effective second-tier test to assist the clinician to accurately diagnose newborns with a suspected IEM.
Subject(s)
Exome Sequencing/methods , Exome/genetics , Metabolism, Inborn Errors/diagnosis , Metabolism, Inborn Errors/genetics , Multiplex Polymerase Chain Reaction/methods , Neonatal Screening/methods , Acyl-CoA Dehydrogenase/deficiency , Acyl-CoA Dehydrogenase/genetics , Amino Acid Metabolism, Inborn Errors/genetics , Citrullinemia/genetics , Genetic Counseling , Genotype , Glutarates , Glycine N-Methyltransferase/deficiency , Glycine N-Methyltransferase/genetics , Heterozygote , Humans , Infant, Newborn , Lipid Metabolism, Inborn Errors/genetics , Male , Molecular Diagnostic Techniques/methods , Mutation , Phenylalanine Hydroxylase/genetics , Phenylketonurias/diagnosis , Phenylketonurias/genetics , Prospective Studies , Retrospective Studies , Tandem Mass Spectrometry/methodsABSTRACT
OBJECTIVE: To investigate the function and underlying mechanism of transforming growth factorbeta (TGF-ß)/bone morphogenetic protein (BMP) signaling pathway in early unexplained miscarriage. STUDY DESIGN: Expression profiles of genes involved in TGF-ß/BMP signaling pathway were compared between placental villous tissue samples from 2 women with missed abortion and those from 2 women with induced abortion by microarray assay. The protein expression level of the most downregulated geneLEFTY1was further measured using western blotting in another 8 women with missed abortion and 7 women with induced abortion. RESULTS: A total of 24 genes showed differential expression level between the 2 groups. Their functions were further investigated, of which 6 of 13 upregulated genes were TGF-ß responsive genes. The most reduced gene is LEFTY1, an antagonist of TGF-ß ligand. The protein expression level of LEFTY1 was confirmed to show the same trend as microarray using western blotting. CONCLUSION: A reduced expression of LEFTY1 in women with missed abortion was identified as com-pared with women with induced abortion, which may result in a dysregulation of TGF-ß signaling and may be the underlying mechanism of missed abortion.
Subject(s)
Abortion, Missed/metabolism , Chorionic Villi , Left-Right Determination Factors , Adult , Chorionic Villi/chemistry , Chorionic Villi/metabolism , Female , Gene Expression Regulation, Developmental , Humans , Left-Right Determination Factors/analysis , Left-Right Determination Factors/genetics , Left-Right Determination Factors/metabolism , PregnancyABSTRACT
Misuse of antibiotics by the medical profession is a global concern. Examining doctors' knowledge about antimicrobials will be important in developing strategies to improve antibiotic use. The aim of the study was to survey Chinese doctors' knowledge on antibiotics and reveal the factors associated with their level of knowledge. A cross-sectional survey was conducted in Shanxi in central China. A total of 761 physicians were surveyed using a structured self-administered questionnaire. A generalized linear regression model was used to identify the factors associated with doctors' knowledge on antibiotic. Based on a full score of 10, the average score for doctors' knowledge on antibiotics was 6.29 (SD = 1.79). Generalized linear regression analysis indicated that doctors who either worked in the internal medicine department, who were chief doctors or who received continuing education on antibiotic, had better knowledge of antibiotics. Compared with doctors working in tertiary hospitals, doctors working in secondary hospitals or primary healthcare facilities had poorer knowledge about antibiotics. Chinese doctors have suboptimal knowledge about antimicrobials. Ongoing education is effective to enhance doctors' knowledge, but the effect remains to be further improved. More targeted interventions and education programs should improve knowledge about antimicrobials, especially for doctors working in primary healthcare institutions.
Subject(s)
Anti-Bacterial Agents/administration & dosage , Drug Utilization Review , Physicians/psychology , Adult , China , Female , Humans , MaleABSTRACT
Flow cytometry was used to analyze the changes in lymphocyte subsets in the youngest child with avian influenza in China. During the early stage, the absolute CD3 count was 62.9% (lower limit of normal), the CD8 count was 32.5% (slightly higher than normal), and the CD4 count was 28.6% (lower than normal). The CD4/CD8 ratio was also decreased (0.88). The natural killer (CD3CD1656) cell count was 4.9% (lower than normal). During the convalescent stage, the CD4 count and the CD4/CD8 ratio returned to normal. The CD3CD1656 count increased from its value at the early stage of the disease.
