Search PubMed⌕ Search

Biomedical subjects

G P Henry

Publications and source records attributed to G P Henry.

11 recordsLinked to original sources
PubMed1999

International, collaborative assessment of 146,000 prenatal karyotypes: expected limitations if only chromosome-specific probes and fluorescent in-situ hybridization are used.

The development of chromosome-specific probes (CSP) and fluorescent in-situ hybridization (FISH) has allowed for very rapid identification of selected numerical abnormalities. We attempt here to determine, in principle, what percentage of abnormalities would be detectable if only CSP-FISH were performed without karyotype for prenatal diagnosis. A total of 146 128 consecutive karyotypes for prenatal diagnosis from eight centres in four countries for 5 years were compared with predicted detection if probes for chromosomes 13, 18, 21, X and Y were used, and assuming 100% detection efficiency. A total of 4163 abnormalities (2.85%) were found including 2889 (69. 4%) (trisomy 21, trisomy 18, trisomy 13, numerical sex chromosome abnormalities, and triploidies) which were considered detectable by FISH. Of these, 1274 were mosaics, translocations, deletions, inversions, rings, and markers which would not be considered detectable. CSP-FISH is a useful adjunct to karyotype for high risk situations, and may be appropriate in low risk screening, but should not be seen as a replacement for karyotype as too many structural chromosome abnormalities will be missed.

Chromosome Aberrations↗
PubMed1992

Early amniocentesis.

Early amniocentesis (EA) refers to any genetic amniocentesis performed prior to 15 weeks, 0 days' gestation. Because of technical problems, most practitioners stopped doing amniocenteses prior to 15 weeks' gestation in the late 1970s. The development of ultrasound-monitored needle insertion has allowed improved success and safety of sampling at earlier gestations, and improvements in laboratory techniques have allowed a high degree of success in culturing and processing low-volume samples. We present information on 1,805 early amniocenteses, of which 35% were performed prior to 14 weeks, 0 days' gestation. Our data indicate that with operator experience the success rate of the procedure can be similar to that seen with routine amniocentesis and that laboratory experience is not different from that with routine amniocentesis (RA) as measured by culture success, time to completion and accuracy. Pregnancy outcome, as measured by the gestational age at delivery, mode of delivery, birth weight and Apgar score, is indistinguishable between RA and EA patients. Although a randomized study is needed to accurately evaluate the fetal loss rate, the rate of birth defects and incidence of neonatal complications associated with EA procedures and examination of the crude rates for the above three parameters show that they compare favorably to the rates reported for patients who have undergone chorionic villus sampling or RA.

Abortion, Spontaneous↗
PubMed1985

Prenatal diagnosis by amniocentesis.

One of the major applications of somatic cell genetics to clinical medicine is in the area of prenatal diagnosis by genetic amniocentesis, which permits the accurate prediction of fetal disease and allows pregnant women to selectively maintain unaffected fetuses. The more recent developments in recombinant DNA research promise to expand tremendously the potential of this technique.

Amniocentesis↗
PubMed1984

Human in vitro fertilization in a private program: Reproductive Genetics in Vitro, P.C.

Reproductive Genetics in Vitro, P.C., began a program of human in vitro fertilization in a private practice setting in September of 1982, after nearly 1 year of preparation prior to the cycling of the first patient. Ovarian stimulation is most often by Clomid, 50 mg tid, on days 3 through 9 of the cycle. Follicle development is monitored by daily ultrasound, estradiol, follicle-stimulating hormone (FSH), and luteinizing hormone (LH) measurements. Serum progesterone measurements are made the last few days prior to anticipated ovulation to detect early signs of luteinization. In the first phase of our program 12 patients with pure tubal obstruction have had one or more oocytes retrieved by laparoscopy. All oocytes fertilized such that every patient who had oocytes retrieved had embryos placed in the uterus. Of the first 12 patients who had embryo placement, 2 are ongoing and normal in the second trimester of pregnancy, with delivery expected shortly after the first issue of this journal. Five others showed early signs of clinical pregnancy as indicated by acentrically located gestational sacs (as opposed to the typical centrally located pseudogestational sac) or transiently elevated human chorionic gonadotropin (HCG).

Adult↗
PubMed1982

A surgical approach to the treatment of fetal hydrocephalus.

Untreated fetal hydrocephalus results in gross cranial and facial abnormalities and profound brain damage. In an attempt to prevent both, a ventriculoamniotic shunt was implanted in a fetus with probable X-linked aqueductal stenosis and hydrocephalus. Performed at 24 weeks' gestation, the procedure used techniques similar to those used for intrauterine transfusion. After shunt placement, the fetal head size grew normally until after the 32d week, when the shunt failed. A cesarean delivery was performed at 34 weeks' gestation. The infant received a standard ventriculoperitoneal shunt after delivery, and his neonatal course has been evaluated through the first three months of life. In selected cases, the ventriculoamniotic shunt may be an acceptable treatment for fetal hydrocephalus.

Adult↗
PubMed1982

A comparison of two schedules of cytosine arabinoside used in combination with adriamycin and 6-thioguanine in the treatment of acute myelogenous leukemia.

The most effective schedule of cytosine arabinoside (Ara-C) administration remains controversial and is further confused by the use of combination chemotherapy. Two remission induction regimens comprising adriamycin, Ara-C, and 6-thioguanine have been compared in patients with acute myelogenous leukemia. Administration of Ara-C by continuous intravenous infusion resulted in faster clearing of leukemic blasts from the peripheral blood and bone marrow than after administration of the same dose by twice daily intravenous injection. Myelosuppression and gastrointestinal toxicity were, however, more pronounced when Ara-C was given by infusion. The complete remission rate was higher in the patients treated with intravenous infusions. It is too early to assess the duration of remission in the infusion study; however, despite the relatively low remission rate, 80% of patients under the age of 60 in the intravenous bolus study remain in remission with a minimum follow-up of two years.

Adult↗
PubMed1978

Prenatal genetic diagnosis: nine years experience.

The advent of techniques for the prenatal diagnosis of disease represents one of the most important advances in clinical genetics of the past decade. It has made it increasingly possible for parents to make informed decisions about reproduction. Physicians should think of genetic amniocentesis as one more method of assessing the status of a fetus at risk. It should be undertaken for a medical indication only, but the safety and accuracy are sufficiently established for it to be considered an integral part of providing high risk obstetrical care.

Adult↗
PubMedDate not supplied

The relationship between the pharmacokinetics of amrinone in the marmoset and platelet effects.

The pharmacokinetic characteristics of amrinone have been studied in six female marmosets following oral administration of 1, 12.5, 25, 50 and 75 mg.kg-1 and an intravenous dose of 1mg.kg-1. The mean plasma AUC0 infinity was determined at each dose level; the values obtained were 2.5, 18.7, 33.9, 103 and 312 micrograms.h.ml-1 for the oral doses of 1, 12.5, 25, 50 and 75 mg.kg-1 respectively and 1.9 micrograms.h.ml-1 for the intravenous dose of 1mg.kg-1. Mean maximum observed plasma concentrations were 0.6, 7.1, 11.7, 23.7 and 40.0 micrograms.ml-1 respectively following oral doses. Over the range 1 to 50 mg.kg-1 the AUC0 infinity was linear; at 75 mg.kg-1 the AUC0 infinity was disproportionately greater. Elimination appeared to be first order over the dose range 1 to 50 mg.kg-1 and the t1/2 in the marmoset was approximately 1 to 3 hours over this dose range. The plasma levels achieved are discussed in relation to the observed effects on the platelet population in this species following chronic administration at high dose levels.

Administration, Oral↗