Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019163 (hepatitis B)
38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vitro enzymatic amplification was applied to detect hepatitis B virus (HBV) DNA sequences in serum. This technique, known as the polymerase chain reaction (PCR) was used to amplify a 128 bp DNA fragment including a 112 nucleotide long sequence complementary to a region in the S gene of the HBV genome. Amplified samples were subjected to spot-test hybridization and scintillation counting using a 32P-labeled oligonucleotide probe. A kinetic study, performed for 4 to 32 PCR cycles with a viral particle preparation, showed a time-limited exponential accumulation of the specific amplified DNA fragment. Amplification yield after 32 cycles was at least 4 X 10(6) with a detection limit equal to 3 X 10(2) viral particles per ml of serum. As the reliability of the PCR technique was greatest for 24 PCR cycles, these conditions were used to develop a quantitative test with a detection limit of 4 X 10(4) viral particles per ml of serum. Results of this test were perfectly correlated with those obtained from the classical spot test without amplification. Ethidium bromide stained agarose gel and Southern blot analysis confirmed the specific amplification of the 128 bp HBV DNA fragment.
...
PMID:Detection of hepatitis B virus sequences in serum by using in vitro enzymatic amplification. 341 Sep 30

Intercalating agents, some of them in clinical use, were tested for their ability to inhibit the hepatitis B virus specific DNA polymerase reaction. Ethidium bromide was shown to be the strongest inhibitor among the compounds tested. Compounds in clinical use inhibited the DNA polymerase test only at high concentrations. The inhibitory activity of all compounds tested was increased when the MgCl2 content in the reaction mixture was lowered. UV absorption studies presented no evidence that this effect was due to complex formation of magnesium and the individual compounds. The therapeutic significance of these findings is not certain and needs further work.
...
PMID:Inhibition of hepatitis B virus specific DNA polymerase by intercalating agents. 738 12