Effect of subarachnoid hemorrhage on serotonin uptake and metabolism in rabbit basilar artery.

The effects of subarachnoid hemorrhage (SAH) on neuronal uptake and metabolism of serotonin (5-HT) in the rabbit basilar artery were examined. Extracted 3H-amines from the isolated arteries after incubation with [3H]5-HT were separated by column chromatography. Radioactivity of 5-HT and 5-hydroxyindoleacetic acid was, respectively, 52.

Experimental basis for increasing the therapeutic index of carboplatin in brain tumor therapy by pretreatment with WR compounds.

We tested an experimental strategy to decrease the dose-limiting hematotoxicity of carboplatin without compromising its activity against brain tumors. The effect of pretreatment with WR-1065, a chemomodifier that penetrates brain poorly, on carboplatin's cytotoxicity was evaluated in human hematopoietic granulocyte-monocyte progenitor cells and in three human glioblastoma cell lines. WR-1065 reduced bone marrow toxicity without decreasing carboplatin's activity against glioblastoma cells.

Molecules of the early equine trophoblast.

Three monoclonal antibodies raised against equine trophoblast cells were tested to determine the characteristics of the identified molecules. First, the antibodies were used to precipitate molecules from radiolabelled equine trophoblast cells of the chorionic girdle. Antibody F71.

Acetylcholine binding by a synthetic receptor: implications for biological recognition.

The neurotransmitter acetylcholine (ACh) is bound with 50-micromolar affinity by a completely synthetic receptor (host) comprising primarily aromatic rings. The host provided an overall hydrophobic binding site, but one that could recognize the positive charge of the quaternary ammonium group of ACh through a stabilizing interaction with the electron-rich pi systems of the aromatic rings (cation-pi interaction). Similar interactions may be involved in biological recognition of ACh and other choline derivatives.

Laboratory studies of berberine used alone and in combination with 1,3-bis(2-chloroethyl)-1-nitrosourea to treat malignant brain tumors.

Berberine was evaluated for antitumor activity against malignant brain tumors. In addition, studies on combination of berberine with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) were done. Several experimental approaches were used.

Assessing information for consumers on the quality of medical care.

In recent years support for better public information on the quality of medical care has intensified, while the validity of the information available has been questioned. To address these concerns, we evaluated the reliability and validity of using each of 10 possible indicators to measure hospital and physician quality and the feasibility of providing the results to the public. We found that several of these indicators can provide useful, though not definitive, information on quality.

Isolation and partial purification of growth factors with TGF-like activity from human malignant gliomas.

The effect of concentrated conditioned medium from each of eight human malignant glioma cell lines on the growth of indicator cells (normal rat kidney fibroblasts (NRK), clone 14) was determined in monolayer and in soft agar assay systems. The conditioned medium from all cell lines was mitogenic in the monolayer assay, but only SF-210, U-343 MG-A, and U-251 MG produced soluble factors that caused NRK cells to grow in soft agar. The soluble growth-promoting factors from these three cell lines were acid- and heat-stable (60 degrees C for 30 minutes) but were inactivated by trypsin (100 microns/ml) and dithiothreitol (50 microM).

Measuring the shape and volume of an above-knee stump.

A set of design criteria for sensing the shape of an above-knee (AK) stump is presented and used as the basis for evaluating various shape sensing technologies. A mechanical probe type shape sensing system is described and its use in quantifying the external shape of the AK stump is discussed as it relates to generating a grid for finite element analysis in CAD/CAM studies and comparing the segmental volumes of the loaded and unloaded stump. This study also discusses a method that uses circumferential measurements to compute total and incremental volumes of the stump.

Trichinella spiralis infections of inbred mice: genetics of the host response following infection with different Trichinella isolates.

The immune response of inbred strains of mice was studied following infection with isolates of Trichinella from a pig (P1), an arctic fox (AF1), and T. spiralis var. pseudospiralis (TP).

Trichinella spiralis infections of inbred mice: immunologically specific responses induced by different Trichinella isolates.

The immune response of inbred mice was studied following infection with Trichinella spiralis var. pseudospiralis (TP) or with isolates of T. spiralis derived from a pig or from an arctic fox.

Partial characterization of a soluble mitogenic factor from medulloblastoma.

To determine how medulloblastoma cells might influence the proliferation and phenotype of normal stromal cells, normal human leptomeningeal cells were treated in culture with medulloblastoma-conditioned medium; their ability to incorporate tritiated thymidine and synthesize collagen was measured. The treated leptomeningeal cells had a significantly greater uptake of tritiated thymidine and grew faster than control leptomeningeal cells. Immunofluorescence studies demonstrated a greater intensity of staining for procollagen type III in the cell layer of the treated cultures than in control cultures; diethylaminoethyl (DEAE)-cellulose chromatography of the medium showed that the treated cells synthesized predominantly type III collagen, whereas control cells synthesized type I collagen.

Comparison of in vitro cloning assays for drug sensitivity testing of human brain tumours.

Three in vitro clonogenic assays were used to determine the sensitivity of an established human glioblastoma cell line (U251-MG) to five chemotherapeutic agents. The colony-forming efficiency of untreated culture was 0.695 +/- 0.

Growth of a medulloblastoma on normal leptomeningeal cells in culture: interaction of tumor cells and normal cells.

Well-characterized medulloblastoma cells growing in suspension were placed on top of a confluent monolayer of leptomeningeal cells. In contrast to cells placed on plastic alone, which did not grow or attach, the medulloblastoma cells attached readily to the leptomeningeal cells and grew to form enlarging spheroids. The growth of these spheroids was supported with minimal essential medium containing 10% fetal calf serum or with human cerebrospinal fluid.

Application of in vivo and in vitro pharmacokinetics for physiologically relevant drug exposure in a human tumor clonogenic cell assay.

The biological half-lives and decay rate constants under the conditions of a human brain tumor clonogenic cell assay were determined for six clinically used anticancer agents. The agents studied were: 1,3-bis(2-chloroethyl)-1-nitrosourea; 3-(2-chloroethyl-3-nitrosoureido-2-deoxy-D-glucopyranose; cis-diaminedichloroplatinum(II); 2,5-diaziridinyl-3,6-bis-(carboethoxyamino)-1,4-benzoquinone; 4-demethylepipodophylotoxin-D-thylidene glucoside; and 9-hydroxy-2-N-methylellipticine. In vitro decay of all six drugs was found to be according to first order kinetics.

A pulsed Doppler ultrasonic system for making noninvasive measurements of the mechanical properties of soft tissue.

In response to the need for a more precise means of predicting the interaction of a prosthetic socket with an amputee's residual limb, a gated Doppler ultrasonic motion sensing system was devised for making noninvasive measurements of the elastic modulus of soft tissue in vivo. Ultrasound was chosen for its ability to indicate the viscoelastic behavior of biological materials without damaging tissue. The system consists of a holding jig to support the limb being tested, a tissue vibrator, and an ultrasonic transducer to monitor the motion of the tissue.

Establishment and characterization of five cell lines derived from human malignant gliomas.

We established and characterized five cell lines derived from human malignant gliomas (four glioblastomas multiforme and one highly anaplastic astrocytoma). All cell lines exhibited tumor cell morphology and growth kinetics, and anchorage-independent growth in soft agar. Cytogenetic analysis revealed significant aneuploidy in all five cases as well as clonal chromosomal alterations unique to each cell line.

Establishment and characterization of a cell line from a human gliosarcoma.

A human gliosarcoma culture was characterized from the time of inception to the time of establishment of the cell line (SF-539 BT). Immunohistochemical analysis of the original tumor showed 2 distinct regions of cells. The gliomatous regions were identified by immunostains for glial fibrillary acidic protein and the sarcomatous regions by immunostains for laminin, collagen type IV, procollagen type III, and fibronectin.

Characterization of normal human brain cultures. Evidence for the outgrowth of leptomeningeal cells.

To establish the histogenetic identity of the predominant cell type in monolayer cultures of normal human adult brain, eight brain specimens were placed into culture and characterized according to cell kinetics, karyotype, antigenic expression, and ultrastructural features. The protein profiles of both the cell layer and the medium were analyzed in selected cultures using sodium dodecyl sulfate polyacrylamide gel electrophoresis and diethylaminoethyl cellulose chromatography. All cultures displayed a limited life span in vitro; marked contact inhibition at confluence; a normal karyotype; an intracytoplasmic and extracellular glycoprotein profile consisting of fibronectin, procollagen type III, laminin, and collagen type IV; specialized intercellular junctions; and interstitial collagen chain synthesis.