Biomedical subjects

J Sam

Publications and source records attributed to J Sam.

At least 19 recordsLinked to original sources

PubMed1993

Use of a heat exchanger to prevent hypothermia during thoracic and thoracoabdominal aneurysm repairs.

Hypothermia is a common unplanned occurrence in many patients undergoing repair of thoracic and thoracoabdominal aneurysms. Many undesirable side effects of hypothermia have been documented, including decreased cardiac output, conduction abnormalities, and blood coagulopathies. We have developed a simple system that incorporates a Sci-Med Biotherm heat exchanger into our left heart bypass circuit. This provides us with the ability to actively rewarm the patient safely and efficiently. This study looks at 16 consecutive patients undergoing repair of thoracic or thoracoabdominal aneurysms. In the 9 patients in whom the heat exchanger was used, there were no adverse effects related to the heat exchanger. All patients had significantly higher temperatures at the conclusion of the procedure than the 7 patients in whom the heat exchanger was not used.

Aortic Aneurysm↗

PubMed1989

Phase I and pharmacokinetic evaluation of thiotepa in the cerebrospinal fluid and plasma of pediatric patients: evidence for dose-dependent plasma clearance of thiotepa.

A Phase I trial of thiotepa (TT) administered as an i.v. bolus was performed in 19 children with refractory malignancies. The starting dose was 25 mg/m2 with escalations to 50, 65, and 75 mg/m2. Seven additional patients were treated with 8-h infusions at 50 or 65 mg/m2. The maximum tolerated bolus dose was 65 mg/m2. Reversible myelosuppression was the dose-limiting toxicity. The plasma and cerebrospinal fluid (CSF) pharmacokinetic parameters of TT and its major active metabolite tepa (TP) were also evaluated. When the bolus or infusion methods of TT administration were compared, there was little difference observed in any pharmacokinetic parameter for either TT or TP. The plasma disappearance of TT was rapid and biphasic with half-lives of 0.14 to 0.32 and 1.34 to 2.0 h. Dose-dependent pharmacokinetics was demonstrated by steadily declining plasma clearance with increasing TT dose. Clearance values declined from 28.6 liters/m2/h at the 25-mg/m2 dose to 11.9 liters/m2/h at the 75-mg/m2 dose. The half-life of TP was longer than that of TT and ranged between 4.3 and 5.6 h. There was evidence of the saturation of TP production. TT and TP both exhibited excellent penetration into the CSF, producing lumbar and ventricular concentrations which were nearly identical to simultaneous plasma concentrations. In one patient with a Rickham reservoir, the CSF:plasma area under the (concentration x time) curve ratios for TT and TP were 1.01 and 0.95, respectively. The above data indicate that TT can be safely administered to pediatric patients at doses higher than conventionally used. The favorable CSF penetration of TT and TP suggests that Phase II studies of TT be considered in patients with central nervous system tumors.

Adolescent↗

PubMed1976

Epimeric 5-hydroxy-5-phenyl-1-azabicyclo [5.4.0] undecanes.

The development of order during the aging of aluminum hydroxide gel prepared by the reaction of aluminum chloride and ammonium hydroxide to a final pH of 7.0 can be monitored by differential thermal analysis. The loss fo acid reactivity upon aging is accompanied by an increase in the temperature and intensity of the dehydroxylation endotherm and an accompanying decrease in the intensity of the water of hydration endotherm. With continued aging, the thermogram develops the characteristics of a crystalline aluminum hydroxide.

Analgesics↗

PubMed1975

3-Arylquinolizidines, potential antidepressant agents.

The synthesis, structure elucidation, and pharmacological evaluation of some 3-arylquinolizidines as semirigid phenethylamines are described. Many of the derivatives posses antidepressant activity. Some anticonvulsant effects are noted.

Acoustic Stimulation↗

PubMed1974