Predictive value of cerebrospinal fluid polyamines in medulloblastoma.

Seventy-five cerebrospinal fluid polyamine determinations were evaluated in 16 patients with medulloblastoma. Parameters utilized in evaluating patient status for correlation with the polyamine concentrations were neurological examination, computerized tomography, radionuclide scan, myelography, and cerebrospinal fluid cytology. Fifteen of the 16 patients showed absolute correlation with the eventual clinical picture.

The effect of phenobarbital pretreatment on the antitumor activity of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) and 1-(2-chloroethyl)-3-(2,6-dioxo-3-piperidyl-1-nitrosourea (PCNU), and on the plasma pharmacokinetics and biotransformation of BCNU.

Many patients being treated for primary and secondary brain tumors receive phenobarbital as an anticonvulsant. The effects of chronic oral administration of phenobarbital on the antitumor activity of BCNU, CCNU and PCNU against the intracerebral 9L tumor in rats were determined. Phenobarbital pretreatment eliminated the antitumor activity of BCNU and reduced the activity of PCNU and CCNU.

Quantitative aspects of contrast enhancement in cranial computed tomography.

The temporal relationship of blood iodine levels to tumor enhancement in cranial computed tomography was studied in a series of patients. Both the bolus and biphasic techniques were evaluated. Peak tumor intensity may not develop immediately, but may be more pronounced on a 20-minute scan.

BCNU-5-fluorouracil combination therapy for recurrent malignant brain tumors.

Twenty-nine patients with recurrent malignant brain tumors were evaluated. BCNU (180 mg/m2) was administered iv on Day 1 and 5-fluorouracil (1 g/m2/day) was given by continuous infusion on Days 15--17. Courses were repeated every 6 weeks until tumor progression occurred.

[Structural organization of the intraorganic circulatory bed of the human gingiva].

By means of injected and noninjected methods, structural organization and morphological structure of some parts of the gum microcirculatory bed have been studied in 46 persons at the age of 22--76 years. It has been stated that a fixed gum is characterized by uneven vascular distribution and zonal modulation of the microcirculatory bed. Diffuse capillary surface per 1 mm2 of the fixed gum in persons at the age of 22--50 years is 0.

Chemotherapy of recurrent medulloblastoma with combined procarbazine, CCNU, and vincristine.

Seventeen patients with recurrent medulloblastoma were treated with a combination of three drugs: procarbazine, CCNU, and vincristine (PCV). Tumor recurrence was documented at varying periods following surgery and radiotherapy. Among 16 evaluable patients, ten showed a response to PCV on the basis of subjective neurological improvement and a decrease in tumor size by radiological criteria.

Pharmacokinetics of BCNU in man: a preliminary study of 20 patients.

Using the technique of direct sample insertion selected ion monitoring chemical ionization mass spectroscopy, BCNU levels were measured in vivo in patients and in vitro in serum, sera ultrafiltrates, and buffered Ringer's solution. The disappearance of BCNU in vitro was found to be first-order with a half-time of 11.6 minutes (+/- 0.

Quantitative high-pressure liquid chromatographic procedure for the determination of plasma and tissue levels of 2,4-diamino-5-(3,4-dichlorophenyl)-6-methylpyrimidine (metoprine) and its application to the measurement of brain capillary permeability coefficients.

A high-pressure liquid chromatographic assay for metoprine levels in aqueous media, serum, and tissue extracts has been developed that can measure concentrations of the drug in the 25-100 ng range with accuracy, reproducibility, and ease. The half-time for metoprine disappearance from rat plasma and capillary permeability coefficients for metroprine in rate brain tissue determined with this method are in excellent agreement with values determined for related drugs using labeled compounds.

[Nuclease activity in leukemia altered lymphoid tissue].

Activities of DNAase I, DNAase II, RNAase I and RNAase II were altered in lymphoid tissue during development of lymphoid leukosis in mice of AKR strain, during survival of the leukemic cells as well as in leukemic spleen tissue of mice C57BI with transplantable leukosis La. The enzymatic activity correlated with the step of the process, the rate of leukemic cells proliferation, with dimensions of organs. Variations in the enzymatic activity, as compared with normal state were dissimilar in development of leukosis; activity of the enzymes was either increased or decreased apparently due to their multiple functions in metabolism of nucleic acids.

Computed tomography in the follow-up of medulloblastomas and ependymomas.

The course of 36 patients with medulloblastoma and ependymoma was evaluated prospectively by clinical examination, radionuclide (RN) studies and computed tomography (CT). Seventeen of the 36 patients (47%) had tumor recurrence. Twelve (41%) of the 29 patients with medulloblastoma had recurrent tumors of which 7 of 12 (58%) were at the primary site and 2 of 12 (17%) were within the ventricles while 10 of 12 (83%) were in the subarachnoid space.

Pharmacokinetics of intracarotid artery 14C-BCNU in the squirrel monkey.

A comparison of intravenous to intracarotid artery (ICA) administration of 14C-BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) was made in squirrel monkeys. Radioactivity was measured as soluble drug products and as RNA-, DNA-, and protein-bound radioactivity. The ICA administration of BCNU achieved 190% to 280% higher brain nucleic acid-bound drug levels than use of the intravenous route in the infused hemisphere and 130% to 280% higher levels than in the noninfused hemisphere.

Heritability of UV-sensitivity and photo-reactivation ability in Drosophila embryos.

In Drosophila the UV sensitivity at the zygote stage and PR ability of damage induced by UV irradiation at 290-380 nm are heritable characters. The heritability of those characters is matroclinal. Resistance to UV irradiation dominates over sensitivity, and high PR ability is dominant over low.

Relationship of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) pharmacokinetics of uptake, distribution, and tissue/plasma partitioning in rat organs and intracerebral tumors.

To obtain a clearer definition of the relationship between the structure of BCNU and CCNU and their antitumor activity, we determined the uptake, distribution, and tissue/plasma partition ratios of both compounds in normal organs and intracerebral (ic) 9L tumors in rats. Greater uptake, distribution, and tissue/plasma partition ratios were obtained for parent CCNU in fat, liver, and brain, and for parent BCNU in kidney. CCNU distributes more rapidly and extensively than BCNU only in fatty tissues.

Correlations between experimental chemotherapy in the murine glioma and effectiveness of clinical therapy regimens.

Intracerebral murine glioma 26 was used as a model system for evaluating two-drug combinations of antitumor agents, BCNU was combined with either procarbazine, dianhydrogalactitol, or ellipticine. CCNU was combined with procarbazine. All combinations were more active than the individual drugs alone.

[State of the vascular bed of the lungs and pleura in congenital heart defects with hypovolemia of the lesser circulation].

The status of the vessel bed of the lungs and pleura in congenital heart diseases with hypovolemia of the pulmonary circulation was studied. Morphological manifestations of adaptative changes in the vessels of microcirculation of these organs were found. The importance of the discovered changes in the maintenance of hemodynamic homeostasis under conditions of deficiency of blood inflow into the pulmonary artery is demonstrated.

Analysis for 1,3-bis(2-chloroethyl)-1-nitrosourea by chemical ionization mass spectrometry.

We used chemical ionization mass spectrometry to quantify the cancer chemotherapeutic agent 1,3-bis(2-chloroethyl)-1-nitrosourea in biological fluids. A stable isotope-labeled internal standard was added to the fluid being analyzed. Protonated molecular ion intensity ratios were determined by selected ion monitoring of sample extracts inserted directly into the chemical ionization source.

Brain tumors: criteria of response and definition of recurrence.

The criteria for determining response to therapy and establishing brain tumor recurrence are presented. Basing their conclusions on a series of more than 500 patients, the authors contend that serial scintiscans and computerized axial tomograms can be used to determine accurately the response to therapy and recurrence or tumor regrowth. The problems in evaluating response and tumor recurrence are discussed, with emphasis on those relating to concurrent glucocorticoid therapy and medical conditions such as infection, hematomas, and drug side-effects.

Comparison of 1- and 2-hr delayed brain scans in patients undergoing chemotherapy for primary brain tumors.

Fifty-five patients receiving various forms of chemotherapy for primary brain tumors had brain scans performed at 1 hr and again at 2 hr following injection of the radionuclide. The images were compared for changes in lesion size, lesion intensity, and surgical flap intensity. Sixteen percent (9) of the patients showed a definite increase in size of the lesions and 29% (16) a definite increase in intensity from 1-hr to the 2-hr scan.