An early pregnancy test

A rapid agglutination – inhibition test was realized with hCG-coated sheep erythrocytes and rabbit antibodies to hCG. Determined amount of hCG on the red blood cells and titrated concentration of antibodies allowed the test to be sensitive at 200 UI/l for confirmation of pregnancy at 2-3 weeks (0-5 days following the first missed period). 3.000 tests were implemented in Nha Trang Pasteur Institute and Hanoi Newborn & Mother Protection Hospital showed that confident rate was 99%. The test was then used for diagnosing the urines of women just before their abortion. The results indicated that more than 11% of these women, at less than 15 days following the first their abortion, were not pregnant and should avoid abortion.

A high activity restriction enzyme recognizing GCGC

A study was performed to identify a high activity restriction enzyme recognizing 5’-GCGC-3’. Isoschizomer Hhal is a endonucleaza, which has been found in a bacteria isolated from a soil sample picked up in Nghean province. This enzyme has a similar activity with Hha l but it is a other protein of other host bacteria, therefore, it is temporary called a isoschizomer of Hhal. About the enzyme’s specific, Hhal cleaves 5 standard DNA molecules at 384 sites, in which 215 sites at DNA , 103 sites at DNA T7, 18 sites at x174, 31 sites at pBR 322 and 17 sites at pUC 19. Isoschizomer Hhal with high activity, stable met the need of users and laboratory of Vietnam.

Nucleotide analysis of restricted fragment DNA extremities for characterizing the restriction enzyme cutting activity

Nucleotide analysis of restricted fragment DNA extremities at definite cut sizes identified: there were 3 extremities: flat; cross with DNA 5’; cross with DNA 5’. This study presented a method which able to characterize unknown restriction enzymes by analyzing the cutting extremities of restricted fragments. The method is based on Sanger sequencing of DNA around the cut site and non-radioactive chemical. Klenow reaction had two active characters: analyzing DNA 5’3’ and exonucleasa 3’5’, allowing to determine the type of cutting of restrictive enzymes. This results allowed to identify the cut sizes of two new enzymes: for Sml1, the cut sites occurs within the recognition nucleotide sequence; BciVI recognizing a non-palindrome sequence and cuts outside this sequence.