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Biomedical subjects

M Kastner

Publications and source records attributed to M Kastner.

At least 37 records · Page 2Linked to original sources
PubMed1990

The effect of diagnosis and educational level on therapists' treatment decisions in a regional psychiatric outpatient clinic.

The aim of this study was to investigate a random sample of psychiatric patients referred for treatment at a psychiatric out-patient unit with the purpose of evaluating their demographic structure, epidemiological data, therapist's decision-making process and the interaction between these factors. Positive correlations were found between diagnosis and variables connected to therapeutic decisions. Variables associated with therapeutic decision were found to be influenced by diagnosis at intake as well as by educational status of the patient. Other findings and possible explanations for correlations observed are presented.

Adult↗
PubMed1989

Purification and properties of cytochrome P-450 from liver microsomes of phenobarbital-treated marmoset monkeys (Callithrix jacchus).

One form of cytochrome P-450 from phenobarbital-induced marmoset liver was purified to apparent electrophoretic homogeneity and compared with the major inducible form isolated from rat liver. Whereas spectral properties and molecular weights, as well as catalytic activities towards aminopyrine and ethylmorphine N-demethylation are quite similar, rates of O-dealkylation with enzymes from the two species are considerably different. While ethoxycoumarin deethylation for the marmoset cytochrome is about one-fortieth of that for the rat, ethoxyresorufin and even pentoxyresorufin dealkylations for the marmoset form are not detectable. By contrast, aldrin epoxidation as catalyzed by this cytochrome is about three times as high as that obtained from the rat.

Aldrin↗
PubMed1988

Activation of cyclophosphamide in mouse limb bud cultures using a reconstituted cytochrome P-450 system.

Purified phenobarbital-induced rat liver cytochrome P-450 was incorporated in a reconstituted system containing NADPH-cytochrome P-450 reductase, dilauroyl phosphatidyl choline and sodium cholate. This system was added to organ cultures of limb buds from mouse embryos on day 11 of gestation. Cyclophosphamide (100 micrograms per ml) was used as a "pre-teratogen" and activation was initiated by adding an NADPH-regenerating system. Due to extensive purification, toxicity of the enzyme preparations and residual solubilisation detergents could be greatly reduced. A reconstituted system containing 10-100 pmol cytochrome P-450 per ml without cyclophosphamide caused no noticeable interference with limb development. The same assay containing cyclophosphamide, however, resulted in a pronounced impairment of cartilage differentiation and in the formation of clearly abnormal structures, especially at the paw skeleton. The activity of the reconstituted system declined under the experimental conditions used, but some activating capacity towards cyclophosphamide was still demonstrable after about 2 h of incubation.

Animals↗
PubMed1988

The value of immunocytochemical staining of lymph node aspirates in diagnostic cytology.

This study investigates the applicability of immunocytochemical techniques towards improving the cytological diagnosis of lymph node disorders. Cytocentrifuge preparations of fine needle aspirates were examined using an indirect immunoperoxidase method and the alkaline phosphatase-antialkaline phosphatase method. 36 reactive lymph nodes were evaluated. 23 patients showed T cell predominance as assessed by the presence of CD3+ cells. 13 patients showed an excess of CD24+ cells over CD3+ cells. In all patients the B cell population showed no light chain class restriction. 48 aspirates from patients with B-non-Hodgkin's lymphoma of low malignancy were investigated. The majority of the cells in each of these cases expressed CD24 and 47 cases were monoclonal with respect to their light chain determinants. In 37/48 cases the antibody OKT9 reacted with less than 15% of cells. 18 aspirates were obtained from patients with B-non-Hodgkin's lymphoma of high malignancy. 17 patients showed light chain class restriction and a high percentage of CD24+ (greater than 80%) and OKT9+ (greater than 40%) cells. 8 malignancies were considered to be of T-cell origin. A low percentage (less than 15%) of Ig+CD24+ cells with a high number of CD3+ and/or CD4+ cells suggests a T-cell lymphoma. The majority of neoplastic cells in peripheral T-cell lymphomas (excluding mycosis fungoides) expressed OKT9 and CD3 expression was found to be variable. In 15 cases of Hodgkin's disease, there were 11 correct cytologic diagnoses. A significant number of BerH2 (CD30)+ cells having the morphology of Sternberg-Reed cells supports this diagnosis. 25 aspirates were obtained from patients with metastatic malignant tumours. Marker studies in eight cases helped in distinguishing metastatic malignant tumours from malignant lymphomas. Our findings indicate that the immunocytochemical technique is applicable to cytological material and that the simplicity of the procedure merits application to routine diagnostic cytology.

Antibodies, Monoclonal↗
PubMed1987

Ion-exchange fast protein liquid chromatography; optimization of the purification of cytochrome P-450 from marmoset monkeys.

Fast protein liquid chromatography (FPLC) on Mono Q and Mono S ion-exchange columns was employed to purify marmoset monkey hepatic cytochrome P-450. Cholate-solubilized liver microsomes from untreated animals as well as from animals induced with phenobarbital, beta-naphthoflavone, 3-methylcholanthrene, and ethanol were used as starting materials. Since established purification schemes for extensively studied species, such as the rat, were found to be not directly applicable, a purification method was developed and optimized by studying the effects of varying detergent types, detergent concentrations, elution buffers, pH values, elution salts, and flow-rates on the resolution and recovery obtained in analytical chromatograms.

Animals↗
PubMed1986

Results of in vivo and in vitro studies for assessing prenatal toxicity.

Examples of a combined approach using in vivo as well as in vitro methods for the assessment of prenatal toxicity are presented. The topics discussed include the analysis of the possible embryotoxic potential of valproic acid (VPA), female sex hormones, bis(tri-n-butyltin) oxide (TBTO), and acyclovir and the problem of supplementing in vitro systems with drug-metabolizing activity.

Abnormalities, Drug-Induced↗
PubMed1985

The relevance of alpha-naphthyl acetate esterases to various monocyte functions.

Human monocytes contain a series of alpha-naphthyl acetate (alpha NA) esterases which are not present in other blood cells and which can be specifically inhibited by bis(4-nitrophenyl)-phosphate (BNPP). This inhibitor is non-toxic at the concentration used and thus enabled studies on the possible significance of this enzyme towards various monocyte functions. BNPP has no noticeable influence on adhesion and spreading of monocytes on glass surfaces, nor does it inhibit the phagocytosis of IgG-coated latex particles. BNPP does, however, diminish the spontaneous cytotoxicity of freshly isolated monocytes towards the erythroleukaemic cell line K562. In the single cell assay in agarose, BNPP treatment of monocytes leads to a decrease in the number of lytic and non-lytic effector-target cell conjugates. In contrast, the antibody-dependent cell-mediated cytotoxicity (ADCC) of monocytes as well as the natural cytotoxicity of lymphocytes towards K562 cells are not influenced by BNPP. The present investigations show that monocyte specific alpha NA esterases are involved in the spontaneous cytotoxicity of monocytes toward tumour cells.

Cell Adhesion↗
PubMed1984

A method of test substance removal in agar colony assays using glass capillaries.

A technique has been developed to remove test substances, after defined incubation periods, from clonogenic in vitro assays using agar-containing glass capillaries. Following removal from the capillaries, the entire agar gels were washed in petri dishes and redrawn into new capillaries. Using 8 radioactive biochemicals of molecular masses ranging from 150 to 1300 dalton the kinetics of diffusion between 1 and 20 min were determined. Using a wash solution-to-assay volume ratio of 20:1, a single washing for 10 min yielded between 90% and 99% removal by diffusion of test substances. By incorporating myelopoietic stem cells it was demonstrated that the cells to be assayed can be quantitatively transferred, without loss or stress, out of and back into capillaries. Thus the reversibility of test substance action can examined under defined conditions avoiding technical problems of previous methods.

Colony-Forming Units Assay↗
PubMed1984

Two-dimensional separation of alpha-naphthyl acetate esterases in human leucocytes and platelets.

Normal human leucocytes and platelets contain esterases which hydrolyse alpha-naphthyl acetate (alpha NA). Purified preparations from these cells were investigated by isoelectric focusing and subsequent polyacrylamide gradient gel electrophoresis at pH 9.0. Extractable alpha NA esterases were separated according to isoelectric point (pI) and molecular weight (MW). Monocytes, lymphocytes, granulocytes and platelets contain a unique pattern of alpha NA esterases, most of which can be inhibited by diisopropyl fluorophosphate (DFP; 0.1 mM). Their activity, however, is not affected by eserine (0.1 mM) or p-hydroxymercuribenzoate (1 mM). No protease activity of these enzymes was detected; it is likely that the majority constitute carboxylesterases (EC 3.1.1.1). Monocytes contain five alpha NA esterases which are additionally inhibited by bis(4-nitrophenyl)-phosphate (0.1 mM) and sodium fluoride (40 mM). PIs are in the range 5.7-6.2 and MWs are 145 000, 155 000, 250 000, 290 000 and 340 000. These enzymes are specific for monocytes. Platelets are characterized by a group of alpha NA esterases having pIs between 6.5 and 8.0, these corresponding to MWs ranging from 15 000 to 400 000.

Blood Platelets↗
PubMed1984

Partial purification and characterization of an endogenous granulomonopoiesis inhibitor from calf spleen.

A factor which specifically inhibits the proliferation of murine bone-marrow-cell colonies in vitro was extracted from calf spleen and partially purified. No comparable inhibition in T-lymphocyte or erythrocyte assays was observed, suggesting a possible chalone nature of the factor. The formation of granulocyte and macrophage colonies is inhibited to equal degrees. The factor was found to be non-toxic: Bone-marrow cells exposed to the factor for 5 h proliferated at a normal rate thereafter. Solubility, molecular mass and ionic exchange data of the factor are similar to those found for chalone-like inhibitors derived from other sources. The present inhibitor however does not contain a thiol group, and has no stimulatory effect after oxidation as described previously for similar factors.

Animals↗
PubMed1984

A granulopoiesis inhibitor partially purified from large-scale serum-free cultures of porcine leukocytes.

A method is described for the partial purification of a granulomonopoiesis inhibitor derived from 200 l-batches equivalent to 1 kg or 2 X 10(12) leukocytes of porcine blood. Serum-free conditioned media were concentrated and separated via ammonium sulfate precipitation, acetone partitioning, ultrafiltration and gel chromatography. The active substance revealed a molecular mass of 500-700 Da and was not thiol-dependent, thus contrasting it with previously-reported granulopoiesis inhibitors. Inhibition of colony formation in an in vitro myeloid stem cell assay using various colony-stimulating factors showed that mature granulocytes and monocytes were equally affected. Apparent lack of cytotoxicity was suggested using a new reversibility test.

Animals↗
PubMed1984

Assessment of daily iron doses administered to patients with chronic blood loss.

In chronically bleeding patients the hemoglobin concentration in blood (Hb) increases after iron therapy. The iron dose necessary for the maintenance of Hb is proportional to blood loss. A simple method for determining blood loss in chronically bleeding patients is introduced. The amount of iron necessary for an increase of Hb is needed for determination of the daily blood loss. A good correlation between calculated and required iron dosage was found for 14 out of 16 chronically bleeding patients. The calculated dose determined for one patient was below the required value; for the other patient only a slight difference was noted.

Anemia, Hypochromic↗
PubMed1983

Alpha naphthyl acetate esterase in human blood cells with different molecular weights.

Normal human blood cells contain esterases which hydrolyze alpha-naphthyl acetate (alpha NA). Purified preparations of these cells were investigated by polyacrylamide gradient gel electrophoresis at pH 9.0 and subsequent staining of gels for esterase activity. Extractable alpha NA esterase was separated according to molecular weight. alpha NA esterase with molecular weight of 55 000 was observed only in lymphocytes and red cells. Lymphocytes from patients with B-cell chronic lymphocytic leukemia (B-CLL) showed alpha NA esterase with molecular weight of 45 000 instead of 55 000. Esterases with molecular weights of 60 000 and 70 000 were detected in granulocytes monocytes and red cells. Only platelets and red cells exhibited alpha NA esterase with molecular weight of 80 000. alpha NA esterases with molecular weight of 290 000 could be demonstrated in granulocytes and red cells. All blood cells contained esterase with molecular weight of 360 000. alpha NA esterase with molecular weight of 390 000 was detected only in red cells. In all blood cells (without lymphocytes) esterase with molecular weight of 500 000 was demonstrated. Only the enzyme in monocytes, granulocytes and red cells was sensitive to fluoride inhibition.

Blood Cells↗
PubMed1982

Localization and characteristics of ferritin in human bone marrow.

It has been found possible to test ferritin concentrations in the reticulum and hemopoietic cells from human bone marrow by an immunoradiometric assay. Ferritin concentration in healthy test persons amounts to 0.92 +/- 0.38 ng/microgram protein in the reticulum and 0.084 +/- 0.031 ng/microgram protein in hemopoietic cells. In healthy test persons about 90% of the ferritin is localized in the reticulum and about 10% in the hemopoietic cells. The ferritin concentration in the reticulum is decreased in patients having iron deficiency anemia. In these patients only 50-70% of the bone marrow ferritin is localized in the reticulum. Bone marrow ferritin was characterized by a combination of anion-exchange chromatography using Sephadex A-50 and an immunoradiometric assay. Marrow ferritin from healthy persons is eluted at chloride concentrations between 200 and 300 mM. The anion-exchange chromatographic properties of ferritin in the reticulum and hemopoietic cells are identical.

Anemia, Hypochromic↗
PubMed1980

Pure bovine granulocytes as a source of granulopoiesis inhibitor (chalone).

In order to isolate an endogenous inhibitor (chalone) of granulopoiesis, a source of chalone has been employed which consists of pure granulocytes. Optimal conditions for the isolation of these cells from bovine blood using EDTA are described. After incubation of the cells, the conditioned medium was lyophilised and extracted in two separate procedures with water or acetone. Sephadex G-10 chromatography yielded a fraction having a molecular weight under 700 which was capable of inhibiting the colony formation of myelopoietic stem cells in a nontoxic, cell-specific and reversible manner. THE INHIBITORy activity of the fraction was found to be dependent on the addition of 2-mercaptoethanol. Even then, aqueous solutions of the inhibitor are at present not indefinitely stable.

Animals↗