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J Hynes

Publications and source records attributed to J Hynes.

4 recordsLinked to original sources
PubMed1990

Multiple-sited (heterotopic) pregnancy after in vitro fertilization and gamete intrafallopian transfer.

Pregnancies occurring simultaneously in different body sites (heterotopic pregnancies) are a rare condition thought to occur in 1 of 30,000 spontaneous pregnancies. Individual cases may occur after in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT). In the past 4 1/2 years, our unit has performed 6,204 IVF/GIFT or pronuclear stage transfer cycles of treatment. Ten such pregnancies proven by surgical, ultrasound, and histological diagnosis have occurred. In the same period 640 IVF, 355 GIFT, and 6 pronuclear stage transfer clinical pregnancies were achieved. This suggests that the incidence of heterotopic pregnancy after assisted reproduction is closer to 1 of 100 pregnancies. Clinicians managing early complications of IVF, GIFT, and/or pronuclear stage transfer pregnancies should be aware of this relatively high incidence of concomitant intrauterine and extrauterine pregnancy.

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PubMed1989

Synergy between 5,10-dideaza-5,6,7,8-tetrahydrofolic acid and methotrexate in mice bearing L1210 tumors.

In vivo studies with 5,10-dideaza-5,6,7,8-tetrahydrofolic acid (DDATHF), an inhibitor of glycinamide ribonucleotide transformylase, indicate that at doses ranging from 2.5 to 10 mg/kg, it prolongs the survival of mice implanted with L1210 tumors. Lower doses of this agent have no effect. Parallel studies with methotrexate indicate that DDATHF is not as potent or as efficacious as methotrexate in this animal model. Low doses of DDATHF combined with low doses of methotrexate can cause a significant increase in the survival of L1210 tumor-bearing mice, suggesting synergism between these two antifolates.

Animals↗
PubMed1979

Purification of mammalian tumor (L1210) thymidylate synthetase by affinity chromatography on stable biospecific adsorbent. Stabilization of the enzyme with neutral detergents.

Thymidylate synthetase from mouse leukemic L1210 cells was purified to electrophoretic homogeneity with 70% yield as a result of an affinity chromatography procedure based on reversible deoxyuridylate-dependent binding of the enzyme to a stable biospecific adsorbent, 10-formyl-5,8-dideazafolate, immobilized on aminoethyl-Sepharose. The presence of neutral detergents, Triton X-100, or Nonidet P40 stabilized thymidylate synthetase during purification. Analytical electrophoresis of the enzyme treated with an excess of 5-fluorodeoxyuridylate and 5,10-methylenetetrahydrofolate showed the presence of two forms of thymidylate synthetase--5-fluorodeoxyuridylate.5,10-methylenetetrahydrofolate complex, indicating that there are two binding sites for 5-fluorodeoxyuridylate present on the enzyme molecule. Molecular weight of native thymidylate synthetase was found to be 75,000, whereas that for the monomer was 38,500.

Animals↗