marrow material taken during therapy, it will be possible to explore if these second cancers emerge before the initiation of thiopurine therapy.4 Second, if de Boer et al are correct in their hypothesis, we would expect a reduced level of DNA-6TGN incorporation in the HGPRT-deficient t-AML/MDS clones compared with the normal bone marrow cells when such cases occur during thiopurine therapy. Usi...

Alternative names: Historically, Lesch-Nyhan syndrome is the designated term for this disease. Lesch-Nyhan Disease (LND) and hypoxanthine-guanine phosphoribosyl transferase (HPRT, HGprt) deficiency are also used to describe this disease. In addition to the classic form of LND, Jinnah and others have characterized two variant forms of the disorder -these individuals have higher levels of enzyme ...

Xanthine phosphoribosyltransferase (XPRT) and hypoxanthine-guanine (HGPRT) are purine salvaging enzymes of Leishmania donovani with distinct 6-oxopurine specificities. LdXPRT phosphoribosylates xanthine, hypoxanthine, guanine, preference toward whereas LdHGPRT only hypoxanthine guanine. In our study, was used as a model to understand these base Mutating I209 V, the conserved residue found in HG...

Hybridomas are the specific cells that have specific character to produce desire antibody. To produce monoclonal antibodies, β cells are removed from the spleen of an animal that has been immunized with the releant antigen. These β cells are then fused with myeloma tumor cells in the presence of PEG. The use of HGPRT cells assured that only hybridomas are selected. The fused hybrid cells (hybri...

Inhibition of poly (ADP-ribose) synthesis by agents such as 3-aminobenzamide (3-AB) potentiates the cytotoxic, carcinogenic, and clastogenic effects of certain DNA-damaging agents. Experiments were carried out in Chinese hamster ovary cells to compare chromosome aberration production and cytotoxicity with the induction of somatic mutations at the hypoxanthine-guanine phosphoribosyltransferase (...

Aquatic and semiaquatic mammals have the capacity of breath hold (apnea) diving. Northern elephant seals (Mirounga angustirostris) have the ability to perform deep and long duration dives; during a routine dive, adults can hold their breath for 25 min. Neotropical river otters (Lontra longicaudis annectens) can hold their breath for about 30 s. Such periods of apnea may result in reduced oxygen...

Inhibition of poly (ADP-ribose) synthesis by agents such as 3aminobenzamide (3-AB) potentiates the cytotoxic, carcinogenic, and clastogenic effects of certain DNA-damaging agents. Exper iments were carried out in Chinese hamster ovary cells to com pare chromosome aberration production and cytotoxicity with the induction of somatic mutations at the hypoxanthine-guanine phosphoribosyltransferase ...

OBJECTIVE Purine enzyme activities may predict the effectiveness of azathioprine treatment and be associated with increased deaths from infectious diseases. In rheumatoid arthritis, patients show variable responses to azathioprine and a higher percentage of death is caused by infections. The aim of the study was to investigate possible rheumatoid arthritis associated abnormalities of purine enz...

BACKGROUND AND AIMS A drug interaction between infliximab and azathioprine has previously been reported in Crohn's disease patients: the concentration of the main active thiopurine metabolites, the 6-thioguanine nucleotides (6-TGN), increased 1-3 weeks after the first infliximab infusion by 50% compared to baseline. The aim of this prospective study was to determine the effect of adalimumab on ...