Search results for "Southern blot"

Molecular hybridization techniques in current diagnosis of chronic hepatitis B in childhood.

1992

Following the cloning and sequencing of the hepatitis B virus genome, molecular hybridization techniques have been established to detect hepatitis B virus (HBV) DNA in serum and liver tissue. Analyses can be performed by dot blot, Southern blot and in situ hybridization. HBV DNA is regarded to be the most sensitive marker of viral replication and infectivity which was previously related to the presence of hepatitis B e antigen in serum and hepatitis B core antigen in liver cells. In liver tissue different molecular patterns can be recognized as free viral DNA and integrated sequences. Furthermore, introduction of the polymerase chain reaction allows the detection of very small amounts of vi…

Gypsy homologous sequences in Drosophila subobscura (gypsyDS).

1993

Characterization of sequences homologous to the Drosophila melanogaster gypsy transposable element was carried out in Drosophila subobscura (gypsyDS). They were found to be widely distributed among natural populations of this species. From Southern blot and in situ analyses, these sequences appear to be mobile in this species. GypsyDS sequences are located in both euchromatic and heterochromatic regions. A complete gypsyDS sequence was isolated from a D. subobscura genomic library, and a 1.3-kb fragment which aligns with the ORF2 of the D. melanogaster gypsy element was sequenced. Comparisons of this sequence in three species (D. subobscura, D. melanogaster, and D. virilis) indicate that th…

Genetic rearrangement of the atzAB atrazine-degrading gene cassette from pADP1::Tn5 to the chromosome of Variovorax sp. MD1 and MD2

2007

International audience; We report the characterization of the rearrangement phenomena responsible for the movement of the atrazine-degrading atzA and B genes from pADP1::Tn5 to the chromosome of Variovorax sp. MD1 and MD2. Long PCRs and Southern blot analyses revealed that the two genes forming a gene cassette moved in a unique rearrangement event. It also revealed that the boundaries of the plasmid sequence inserted in the chromosome correspond to IS1071or to sequences close to IS1071. It suggests that this genetic rearrangement could result from the transposition of the composite transposon delimited by IS1071 insertion sequences and containing atzA and atzB genes. In addition, for MD1 an…

Bgl II restriction fragment length polymorphism of human complement C4A gene coincides with BF*F allele of factor B.

1988

RT-PCR and in situ hybridization analysis of apolipoprotein H expression in rat normal tissues

2006

In this study, by using different techniques (i.e. Northern blot hybridization, RT-PCR and Southern blot hybridization) on various normal rat tissues, we were able to identify liver, kidney, heart, small intestine, brain, spleen, stomach and prostate as tissues in which the ApoH gene is transcribed. Moreover, for some of these tissues, by in situ hybridization, we found a specific localization of apoH transcripts. For instance epithelial cells of the bile ducts in liver and of the proximal tubules in kidney are the major sites of apoH synthesis. Our data suggest that some of the different physiological roles proposed for apoH could correlate with its direct expression, while others could co…

IN SITU HYBRIDIZATION FOR DETECTION OF HEPATITIS B VIRUS GENOMES IN LIVER TISSUE OF CHRONIC INFECTED CHILDREN

1990

Detection of hepatitis B virus (HBV)-DNA in the liver of chronic infected patients is presently the most sensitive marker of viral replication and infectivity. In situ hybridization (ISH) allows the direct visualization of HBV infected liver cells and distribution of the viral sequences. This study was done to establish ISH and correlate the findings with conventional markers for HBV infection. Methods. Liver biopsies of 50 patients (28 ♂, 22 ♀) aged 0.5-20 years (mean 10.3) with various histological diagnoses were tested by 1SH. The HBV-DNA probe was labeled by nick translation with 35S-CTP to a specific activity of 3-5×108 cpm/μg DNA. Results. HBV-DNA/mRNA could be demonstrated in 38 pati…

CHARACTERIZATION OF CHRONIC HEPATITIS B IN CHILDHOOD USING MOLECULAR BIOLOGY TECHNIQUES

1992

The introduction of molecular biology techniques in the diagnostics of chronic hepatitis B virus infection proved HBV DNA to be the most sensitive marker of viral replication and infectivity. The aim of our study was to characterize the HBV DNA status in children with chronic hepatitis B with various molecular biology techniques in relation to conventional HBV markers. Methods: 206 sera of 172 and liver tissue of 108 children with chronic hepatitis B infection were investigated by dot blot-, Southern blot-, and in situ hybridization. In dot blot and Southern blot negative specimens polymerase chain reaction (PCR) was performed. Results: 111 of the 206 sera were positive for HBV DNA by dot b…

Amplification of ETS2 oncogene in acute nonlymphoblastic leukemia with t(6;21;18).

1992

Cytogenetic and molecular studies in a case of acute nonlymphoblastic leukemia (ANLL) are reported in this paper. Bone marrow blasts carried a hypodiploid karyotype with a complex t(6;18;21)(6qter----6p21::21q22----21qter;18qter ----18p11::6p22----6pter; 21pter----21q22::6p21----6p22::18p11----18pte r) and other numerical and structural changes. We studied the organization and the expression of the ETS2 gene which is located on chromosome 21 in order to investigate its possible involvement in the disease. DNA analysis showed a 20-fold amplification of ETS2 sequences; an increase of 3- to 4-fold in the mRNAs level compared to normal was shown by Northern hybridization.

Transmission pattern of hobo transposable element in transgenic lines of Drosophila melanogaster

1998

This study is an attempt to trace the fate of hobo elements in the genomes of E strains of Drosophila melanogaster that have been transfected with pHFL1, a plasmid containing an autonomous hobo. Such long-term population studies (over 105 generations) could be very useful for better understanding the population and genomic dynamics of transposable elements and their pattern of insertions. Molecular analyses of hobo elements in the transfected lines were performed using Southern blots of XhoI-digested genomic DNAs. The complete element was observed in all six injected lines. In two lines we observed, at generation 100, two deleted elements, which did not correspond to Th1 and Th2. The result…

Hepatitis B Virus DNA in Liver Tissue of Chronic HBsAg Carriers in Childhood and Its Relationship to Other Viral Markers

1992

The aim of the study was to examine the state of hepatitis B virus (HBV) DNA in liver tissue of 103 children with chronic hepatitis B aged 0.5-18 years to detect free and integrated viral sequences by Southern blot hybridization. HBV DNA was found in 74 patients. Seventy-two were seropositive for hepatitis B e antigen (HBeAg) and two had anti-HBe antibodies. Integrated sequences could be demonstrated in two children. One of them had only integrated HBV DNA and was anti-HBe seropositive. The other one presented both free and integrated viral sequences and developed seroconversion from HBeAg to anti-HBe 5 months after biopsy. In 29 hepatitis B surface antigen (HBsAg) carriers, no HBV DNA coul…