DNA sensors to assess the effect of VKORC1 and CYP2C9 gene polymorphisms on warfarin dose requirement in Chinese patients with atrial fibrillation.

The optimal dose of warfarin depends on polymorphisms in the VKORC1 (the vitamin K epoxide reductase complex subunit (1) and CYP2C9 (cytochrome P450 2C9) genes. To minimize the risk of adverse reactions, warfarin dosages should be adjusted according to results from rapid and simple monitoring methods. However, there are few pharmacogenetic-guided warfarin dosing algorithms that are based on large cohorts from the Chinese population, especially patients with atrial fibrillation.

Non-invasive prenatal diagnosis of trisomy 21 by reverse transcriptase multiplex ligation-dependent probe amplification.

Background: Obtaining fetal DNA or RNA by either chorionic villus sampling (CVS) or amniocentesis is currently, the gold standard prenatal diagnosis. However, these invasive procedures carry risk of miscarriage. A reliable method for non-invasive prenatal diagnosis (NIPD) has long been sought to reduce the risk of miscarriage.

Development of a multiplex MethyLight assay for the detection of multigene methylation in human colorectal cancer.

In peripheral blood, cell-free methylated DNA has been reported to be a useful biomarker of noninvasive blood screening for the detection of colorectal cancer (CRC), including the genes ALX homeobox 4 (ALX4), septin 9 (SEPT9), or transmembrane protein with EGF-like, and two follistatin-like domains 2 (TMEFF2). Here we report a multiplex MethyLight polymerase chain reaction (PCR) assay that simultaneously detected the methylation status of ALX4, SEPT9, and TMEFF2, as well as quantifying methylation level of these genes in a total of 127 fresh tissue samples and 182 peripheral blood samples from CRC patients. Using the multiplex MethyLight assay, methylated ALX4, SEPT9, and TMEFF2 occurred in 56, 78, and 75% of CRC tissue samples and in 48, 75, and 71% of peripheral blood samples from CRC patients.

The manual Polybrene test has limited sensitivities for detecting the Kidd blood group system.

Background And Objectives: The Kidd system antibodies, if undetected, can cause immediate or delayed hemolytic transfusion reactions as well as hemolytic disease of the newborn. There have been anecdotal reports about the inefficiency of the manual Polybrene test in detecting these antibodies. Here, we sought to determine the sensitivity of the manual Polybrene test in detecting anti-Jk(a) and anti-Jk(b) antibodies and Jk(a) and Jk(b) antigens.

Simultaneous detection of different respiratory virus by a multiplex reverse transcription polymerase chain reaction combined with flow-through reverse dot blotting assay.

Cell culture and immunofluorescence (IF) assays have been traditionally used for the laboratory diagnosis of respiratory viral infections, but these assays have a low sensitivity and are time consuming. We developed a multiplex reverse transcription polymerase chain reaction combined with flow-through reverse dot blotting (mRT-PCR-FT-RDB) assay for the simultaneous detection of influenza virus type A including H5 subtype and H9 subtype, influenza virus type B, parainfluenza virus types 1 and 3, respiratory syncytial virus, human rhinovirus, and human coxsackievirus. In comparison with viral culture and IF assay as the gold standard method, the mRT-PCR-FT-RDB assay gave a sensitivity and a specificity of 100% and 98%.

Development of a multiplex quantitative fluorescent PCR assay for identification of rearrangements in the AZFb and AZFc regions.

The azoospermia factor b (AZFb) and azoospermia factor c (AZFc) regions in the human Y chromosome consist of five palindromes constructed from six distinct families of amplicons and are prone to rearrangement. Partial deletion and duplication in the region can cause azoospermia or oligozoospermia and male infertility. The aim of the study was to establish a quantitative fluorescent PCR (QF-PCR) assay to classify AZFb and AZFc rearrangements.

Development of a multiplex real-time polymerase chain reaction for the detection of influenza virus type A including H5 and H9 subtypes.

Avian influenza viruses (AIVs) are endemic in wild birds and, if transmitted to poultry, can cause serious economic losses. The aim of this study was to develop a multiplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) for rapid detection of influenza virus type A, including H5 and H9 subtypes. The selected primers and various labeled TaqMan reporter probes corresponding to matrix, H5, and H9 genes were used in a multiplex real-time RT-PCR to simultaneously detect triple fluorescent signals.

Determination of hepatitis B virus genotype by flow-through reverse dot blot.

Background: The clinical outcome and response to therapy of hepatitis B virus infection differ depending upon viral genotype. Most methods of determining the viral genotype are relatively time-consuming and costly. Moreover, the results of some methods are influenced by single nucleotide mutations.

Relationship between apolipoprotein E, D10S1225 polymorphisms and late-onset Alzheimer's disease.

Background: There were some papers published in the Jonrnal of Science, December 2000 suggesting that one or more important susceptibility genes for late onset Alzheimer's disease (LOAD) were located on the long arm of chromosome 10. Linkage analysis showed maximum lod score close to D10S1225 loci, which indicated the loci might contribute to the etiology of Alzheimer's disease (AD).

Methods: Fifty-nine LOAD patients and 107 controls were recruited.

Rapid and accurate genotyping of YMDD motif variants in the hepatitis B virus genome by an improved reverse dot blot method.

By using the "flow-through hybridization" principle, we developed a new, rapid and accurate reverse dot blot (RDB) method to detect lamivudine resistance-associated YMDD motif variants in hepatitis B virus (HBV) genome. The improved RDB method was very fast at simultaneously detecting HBV YMDD wild-type and mutant motifs. In a blind analysis, 100 samples previously genotyped by DNA clonal sequencing analysis were used to evaluate the sensitivity and specificity of this assay.

[Advances in the studies of molecular heredity of phenylketonuria].

Phenylketonuria (PKU) is one kinds of autosomal recessive disease caused by phenylalanine hydroxylase (PAH) gene mutation. This article reviews the recent molecular heredity progress on the phenylalanine hydroxylase gene's orientation, structure, and gene mutation and gene regulation. At same time, mutation gene in vitro expression and the character of 3D structure of PAH in PKU are involved.

[Six novel mutations in PAH gene detected by sequencing].

Objective: To explore new mutation in phenylalanine hydroxylase (PAH) gene.

Methods: The PAH genes from 40 phenylketonuria (PKU) patients and 30 normal controls were screened by PCR-single strand conformation polymorphism (SSCP) and further sequencing.

Results: Eleven mutations and 3 polymorphisms in PAH gene were found.

[Molecular characterization of a new mutation E122G of human ornithine transcarbamylase gene].

Objective: To determine the molecular basis of late onset ornithine transcarbamylase (OTC) deficiency in a Chinese family of Han nationality and the exon sequences of OTC gene of this patient.

Methods: Polymerase chain reaction-single strand conformation polymorphism and direct sequencing were used to identify the mutation type.

Results: A missense mutation E122G in the conserved residue of exon 4 was identified which is unreported before.

[Study of immunological indicators in peripheral blood for nasopharyngeal carcinoma].

Objective: To find reliable diagnostic immunological indicators in peripheral blood for nasopharyngeal carcinoma, and to evaluate the possibility of cancer screening and early diagnosis of the malignancies in the future.

Methods: Plasma samples were obtained from 83 patients with nasopharyngeal carcinoma and from 105 patients with benign diseases. Nine cytokines were selected as the candidates for the indicators and their quantity in the plasma samples determined by enzyme-linked immunosorbent assay, the result of which was analyzed statistically.

[Detection of telomerase hTERT gene expression of exfoliated cell in broncho-alveolar lavage fluid].

Background & Objectives: The patients with lung carcinoma usually have high telomerase activity, the pseudopositive result is happen frequently when the test is done with traditional method. Telomerase activity is more strongly correlated with hTERT mRNA. This study was designed to detect the expression of telomerase hTERT gene in broncho-alveolar lavage fluid of the patients with lung carcinomas by relative quantitative RT-PCR method, to afford a useful tool for early and differentiate diagnosis of lung cancer.

Development and clinical trial of fluorescence PCR diagnostic kit to detect Mycobacterium tuberculosis.

Objective: To develop a new diagnostic kit for Mycobacterium tuberculosis (TB) detection on the basis of fluorescence PCR (F-PCR) and conduct clinical trial of this kit for assessing its performance in comparison with other diagnostic methods.

Methods: We collected 546 clinical sputum samples from patients with phthisis and normal subjects to examine TB by way of F-PCR in parallel with examination with modified R.culture, auramine smear with fluorescence staining and LCx DNA diagnostic kit from Abbott for comparison.