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Biomedical subjects

J T Sobota

Publications and source records attributed to J T Sobota.

17 recordsLinked to original sources
PubMed1991

Comparative pharmacokinetics and pharmacodynamics of epoetin alfa and epoetin beta.

Different recombinant human erythropoietin products have been developed. Although they appear to have similar pharmacokinetics and function, these have not been directly compared. This randomized, double-blind, four-period crossover study compared the pharmacokinetics and pharmacodynamics of intravenous and subcutaneous epoetin alfa and epoetin beta in 18 normal male volunteers. As a control, three subjects received placebo treatment. After intravenous administration, the steady-state volume of distribution and beta-phase volume of distribution of epoetin beta were 7.7% and 16.9% larger than for epoetin alfa (p less than 0.05). The terminal elimination half-life after intravenous administration of epoetin beta was 20% longer than the terminal elimination half-life of epoetin alfa. After subcutaneous administration there was a delayed drug absorption with epoetin beta compared with epoetin alfa (p less than 0.05). There was a small but significantly greater absolute reticulocyte response after subcutaneous epoetin beta compared with subcutaneous epoetin alfa. The findings support differences in the pharmacokinetics and function of epoetin alfa and beta that are possibly caused by differences in their glycosylation.

Adolescent↗
PubMed1989

Review of cardiovascular findings in humans treated with minoxidil.

Minoxidil is an antihypertensive vasodilator with no known capability of inducing human cardiovascular pathology; however, the compound does cause a late, canine-specific lesion of the right atrium and acute right atrial and ventricular papillary muscle changes. In all the autopsy cases of minoxidil-treated humans to date, 9 cases were reported with significant right atrial or other cardiac pathology and were carefully reviewed for similarity to either the early or late canine lesion. Three new cases (G, H, and I) were added in this update to 6 cases already described. None of the 3 cases newly analyzed in this paper, as well as the previously reported 6 cases, had gross or histologic constellations which could be diagnosed as associated with minoxidil treatment. Further, the examination of autopsy cases of minoxidil-treated hypertensive right atrial histology findings appear no different than those found in the baseline non-minoxidil treated hypertensive and non-hypertensive cases.

Animals↗
PubMed1977

Prostaglandin E2-hemoglobin AA and SS erythrocyte interaction (prostaglandin-erythrocyte interaction).

Prostaglandin E2 (PGE2), at concentration larger than or equal to 5 x 10(4) ng/ml, induced discocyte leads to echinocyte transformation of saline-suspended hemoglobin (Hb) AA and SS erythrocytes. This erythrocyte transformation is concentration-dependent and is reversible at room temperature after 90-120 min. The Hb SS erythrocytes treated with PGE2 did not exhibit accelerated sickling or increased formation of sickled echinocytes. Erythrocytes suspended in autologous plasma treated with PGE2, 2 X 10(6) ng/ml, did not exhibit echinocytic transformation probably because of drug binding to the plasma proteins. Other in vitro studies showed that PGE2 of concentrations of 10-500 ng/ml had no adverse effects on intact, plasma-suspended Hb SS erythrocytes. These Hb SS erythrocytes were examined for changes in morphology, potassium and calcium flux, and blood viscosity under oxygenated and hypoxic conditions.

Anemia, Sickle Cell↗
PubMed1975

Hormone changes occurring during second trimester abortion induced with 15 (S)-15-methyl prostaglandin F2alpha.

Changes in progesterone, human placental lactogen (HPL), cortisol and estradiol-17B were measured during second trimester abortion induced by I.M. 15-methyl PGF2alpha. A rapid decline in progesterone and HPL was found, indicating perhaps an initial effect on the placenta. A rapid rise in cortisol was found, but it is not clear if this is due to stress or part of the termination mechanism. The changes of estradiol were not as distinct and may reflect opposite effects of the prostaglandin on the placenta and adrenals. Similar hormonal changes were observed regardless of the duration of gestation.

Abortion, Induced↗
PubMed1974

Absence of drug abuse in prisoners in a major correctional institution.

Laboratory evaluation of illicit drug abuse was conducted in a major correctional institution. Fifty-eight prison inmates were screened for common drugs of abuse in conjunction with a triazolo-benzodiazipine compound tolerance protocol. Urine specimens were collected on days -1, 1, 15, 29, and 49 and assayed for amphetamines, opiates, barbiturates, and alcohol. Quinine was detected in two individuals and was probably derived from cold remedy preparations rather than the illegal use of heroin. While occasional illicit drugs may find their way into a prison population, this study showed no evidences of drug abuse in one correctional institution whose prisoners participated in Phase I drug evaluations.

Adult↗