PubMed Health⌕ Search

Biomedical subjects

L M Kleinman

Publications and source records attributed to L M Kleinman.

16 recordsLinked to original sources
PubMed1987

Merbarone: an antitumor agent entering clinical trials.

Merbarone was developed to clinical trial stage on the basis of its 'curative' activity against P388 and L1210 leukemias and moderate activity against B16 melanoma and M5076 sarcoma. Its activity appears to be schedule-dependent favoring a longer duration of administration. The mechanism of action of merbarone is not yet established but it does induce single strand breaks in DNA apparently without binding to DNA. The pharmacokinetic data in the dog indicate that clearance mechanisms may be saturable. Merbarone is hydroxylated at the 4' position in the rat, mouse and dog, and glucuronidated in the dog. Parent drug and the hydroxy metabolite are excreted in the urine. If saturable clearance mechanisms also pertain to man, this will mean that infusion rate (and therefore steady state concentrations reached) may be a significant factor in determining acute toxicity. Preclinical toxicology studies revealed that major target tissues are in the lymphoid organs, bone marrow, gastrointestinal tract and kidney. Some behavioral signs of reversible central nervous system toxicity were observed. Phase I trials have commenced using only a 5-day continuous intravenous infusion schedule based on the preclinical data. The pharmacokinetic information from these trials will be crucial for further clinical development of the compound, including selection of the optimal schedule(s) for phase II/III evaluation.

Animals↗
PubMed1978

Evaluation of some pharmaceutical aspects of intrathecal methotrexate sodium, cytarabine and hydrocortisone sodium succinate.

Methotrexate sodium, cytarabine and hydrocortisone sodium succinate were evaluated in three vehicles, Sodium Chloride Injection, USP, Lactated Ringer's Injection, USP, and Elliott's B solution, an artificial cerebrospinal fluid (CSF). Osmolarity values of all drug solutions studied were within 10% of normal human. No vehicle-related alterations in the stability of methotrexate or cytarabine were detected under simulated use conditions. However, the degradation of hydrocortisone sodium succinate was faster in Elliott's B solution than in the other vehicles. Principal differences among the vehicles involved electrolyte content, pH and buffer capacity. Elliott's B solution is similar to CSF in electrolyte composition and buffer capacity, and was the only vehicle to maintain the pH of dilute methotrexate and cytarabine solutions between 7.2 and 7.8. The significance of these in vitro data await a careful clinical study.

Chemistry, Pharmaceutical↗
PubMed1978

Pharmaceutical assessment of amygdalin (Laetrile) products.

The National Cancer Institute (NCI) recently acquired a large supply of formulated products of amygdalin manufactured by Cyto Pharma of Mexico, for possible use in a clinical trial in the US. Tablets for oral administration and ampules of the injectable produce were obtained. Both forms were extensively analyzed and evaluated by several analytic and pharmaceutical laboratories under contract with the NCI. Analytic test procedures were developed to determine the chemical integrity and quantitative composition of the formulated products. Routine physical and biologic tests were also performed to evaluate the manufacturing quality of both dosage forms. The results indicate that both the oral and injectable forms of amygdalin were substandard by US criteria for manufactured pharmaceutical products. All samples were determined to be chemically subpotent, mislabeled, and of poor manufacturing quality. More than 20 samples of the ampules were found by visual inspection to contain microbial contamination. Other samples were found to be pyrogenic. Based on the results of the testing performed, both tablet and ampule forms of amygdalin manufactured by Cyto Pharma of Mexico are considered unfit for use in man.

Administration, Oral↗
PubMed1977

Serum hepatic enzyme and bilirubin elevations during parenteral nutrition.

Serial liver enzyme and bilirubin concentrations were measured in 100 patients undergoing total parenteral nutrition. Between the eighth and tenth days, serum glutamic-pyruvic transaminase levels rose to 5.4 times pretotal parenteral nutrition levels; serum glutamic-oxalacetic transaminase, 2.8 times; bilirubin, 2.3 times, and lactic dehydrogenase, 1.5 times. These elevations were transient, lasting four to ten days. Biopsies of the liver taken during maximal elevations demonstrated marked periportal fatty change. A second elevation of serum glutamic-pyruvic transaminase, serum glutamic-oxalacetic transaminase, alkaline phosphatase and lactic dehydrogenase occurred in one-third to one-half of those patients receiving total parenteral nutrition for longer than a 20 day period. These elevations were more prolonged, and no biopsies were taken. Amino acid solutions contain conversion products of tryptophan, an amino acid that is unstable in the presence of the preservative sodium bisulfite which is added to all commercially available protein solutions. Infusion of these products into rats, either alone or as part of total parenteral nutrition solutions, resulted in periportal fatty change of the livers identical to that seen in our patients receiving total parenteral nutrition. A toxic effect of tryptophan conversion products in total parenteral nutrition solutions is proposed.

Alanine Transaminase↗
PubMed1975

Chemical structure and purity of dyes used in lymphograms.

Because of confusion in the literature, studies were performed on several samples of patent blue violet and Alphazurine 2G to determine their chemical structure and purity. Nuclear magnetic resonance studies revealed that three distinct compounds and one mixture had all been labeled as the same compound. The purity of the dyes varied from batch to batch, as shown by thin-layer chromatography. Caution should be exercised in the use of these dyes for lymphograms.

Chemical Phenomena↗