PubMed Health⌕ Search

Biomedical subjects

J Plum

Publications and source records attributed to J Plum.

At least 127 records · Page 7Linked to original sources
PubMed1988

Analysis of activation markers on tonsillar T lymphocytes.

Tonsillar T lymphocytes have several characteristics of activated lymphocytes, but the activation antigens are not detected on their surface, except for the Tac antigens by means of a sensitive protein A rosette assay. In this study the increased ability of tonsillar T lymphocyte to form autologous rosettes is presented. These data are in agreement with the hypothesis that tonsillar T lymphocytes contain activated T lymphocytes.

Adolescent↗
PubMed1988

Enzyme analysis of thymic nurse cells.

Thymic nurse cells (TNC) were characterized according to their enzyme content. The following enzymes: Lactate dehydrogenase (LDH) isoenzymes, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) were evaluated. When the enzyme profile of the TNC were compared with the one found in the different thymocyte subpopulations, the ADA/PNP ratio was very low and similar to the early thymocytes, whereas the LDH isoenzymes approached the pattern of the cortical thymocytes. This enzyme profile suggests that the enzyme content of the TNC is dependent on the presence of at least two different thymocyte subpopulations, the early thymocytes and the cortical thymocytes.

Adenosine Deaminase↗
PubMed1987

Analysis of human prenatal and postnatal thymocytes with the anti-Tac monoclonal antibody and recombinant interleukin-2.

The expression of the interleukin-2 (Il-2) receptor on the cell surface membrane of human prenatal and postnatal thymocytes has been studied by flow cytometry. The in vitro responsiveness of these thymocytes to human recombinant Il-2 (rIl-2) was also studied. Prenatal and postnatal thymocytes contained very few Tac positive cells. The different T cell antigens T6, T3, T4, T8, T9, T10, 3A1 and T11 were expressed by the first trimester of fetal development. Recombinant Il-2 alone was able to induce proliferation of human prenatal and postnatal thymocytes. From this study and data in the literature we conclude that hither-to a thymic precursor cell carrying the interleukin-2 receptor as is the case for the murine thymus has not been found in man.

Antibodies, Monoclonal↗
PubMed1986

Detection of digoxin, digitoxin, their cardioactive metabolites and derivatives by high-performance liquid chromatography and high-performance liquid chromatography-radioimmunoassay.

High-performance liquid chromatographic (HPLC) systems are described for the separation of the cardioactive metabolites of the digoxin and digitoxin series that are formed by the splitting of digitoxose sugar residues from the aglycone steroid: isocratic separation of digoxin and its cardioactive metabolites; isocratic separation of digitoxin and its cardioactive metabolites; and gradient elution separation of the digoxin and digitoxin series including beta-acetyl- and beta-methyldigoxin. Separations were performed on a 10-microns bonded octadecyl phase column using various mixtures of acetonitrile--water and acetonitrile--methanol--water as the mobile phase. These methods provide high peak resolution and are well suited for collecting elution fractions, e.g. to link up with sensitive immunological measurements. An HPLC-radioimmunoassay method is described for the quantitation of digoxin, digitoxin and their metabolites in human tissues.

Chromatography, High Pressure Liquid↗
PubMed1986

Human tonsillar T lymphocytes: an immature or activated T-lymphocyte population.

In this study we compare the phenotype and the enzyme content of T lymphocytes purified from tonsils and from circulating blood before and different times after in vitro activation with PHA. The phenotype was studied with the following panel of monoclonal antibodies for the presence of activation antigens: OKT9, OKT10, anti-Dr, and Tac antigen. The enzyme content was studied by estimation of the LDH isoenzyme distribution and the enzymes of the purine metabolism ADA and PNP. In addition, the in vitro responsiveness of the T lymphocytes from tonsils and blood to human recombinant interleukin 2, to the lectins PHA, Con A and PWM was also studied. The LDH isoenzyme pattern expressed as B:A ratio decreases progressively after in vitro activation of T lymphocytes. The B:A ratio is already significantly different as early as 12 hr after activation, at a time that OKT9 and Tac are already expressed, but before the expression of OKT10, HLA-Dr, and the onset of the DNA synthesis. Tonsillar T lymphocytes exhibit also a significantly lower B:A ratio, but the activation antigens are not detected on their surface, except for the Tac antigens by means of a sensitive protein A rosette assay. Tonsillar T lymphocytes have a better responsiveness to lectins and recombinant II-2 than the corresponding circulating T lymphocytes. Therefore we are in favor of the hypothesis that tonsillar T lymphocytes contain activated T lymphocytes.

Adult↗
PubMed1985

[Distribution of digoxin, digitoxin and their cardioactive metabolites in human heart and kidney tissue. A postmortem study].

A method was developed for the specific determination of digoxin and digitoxin, as well as their semisynthetic derivatives and dependent cardioactive metabolites, in autopsy samples of heart and kidney. A collective of six patients on long-term treatment with therapeutic doses of beta-acetyldigoxin had a mean myocardial digoxin content of 46.1 +/- 25.0 ng/g (SD); kidney: 50.3 +/- 30.3 ng/g. Digoxigenin bisdigitoxoside represented the second most important metabolite in heart and kidney; digoxigenin monodigitoxoside and digoxigenin follow, respectively. In a collective of seven patients on maintenance treatment with digitoxin, the mean tissue levels were higher but the metabolic pattern was similar (myocardial digitoxin content: 78.9 +/- 38.4 ng/g, renal content: 104.1 +/- 44.1 ng/g). The amount of digoxin formed by hydroxylation under long-term treatment with digitoxin in heart and kidney were approximately 10 ng/g. A case of digoxin intoxication differed both in the tissue content and in the metabolic distribution.

Adult↗
PubMed1984

Beta-glucuronidase activity in human T and B lymphocytes and the Tmu and T gamma subpopulations.

The beta-glucuronidase staining characteristics of isolated T cell populations and the Tmu and T gamma enriched fractions derived of them were studied. T gamma lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The rosette-forming cells in the pellet were referred to as T gamma lymphocytes, whereas the lymphocytes in the interface were referred to as T gamma depleted or Tmu lymphocytes. B cells were studied on rosetted mononuclear cells with either mouse erythrocytes or with Staphylococcus Aureus (Cowan I) bacteria, after a preceeding polyvalent anti-human Ig treatment of the cells. While B cells showed mostly no reactivity, Tmu and T gamma cells were respectively characterised by a "dot-like" and "granular" pattern of reactivity. These findings are in agreement with those observed by others after alpha-naphthyl-acetate esterase or acid phosphatase staining. Within the T lymphocyte fraction, the T non-mu, non-gamma lymphocytes seemed to have a granular pattern of reactivity. The same staining pattern was found in non-B, non-T lymphocytes.

B-Lymphocytes↗
PubMed1984

LDH isoenzyme distribution in human T gamma lymphocytes.

The lactate dehydrogenase (LDH) isoenzyme distribution was measured in T gamma+ lymphocytes from normal individuals. T gamma+ lymphocytes were obtained from purified T lymphocytes by ox-IgG rosette sedimentation. The B:A subunit ratio was clearly lower in the T gamma+ lymphocytes. Phenotyping of the T gamma+ lymphocytes showed a vast majority of OKT11+, OKM1+, OKT3- lymphocytes. In one experiment, T gamma+ lymphocytes were enriched by OKT3 depletion of T lymphocytes. The low B:A ratio was also found in these cells indicating that the LDH pattern is not the consequence of an in vitro activation by immune complexes. As the T gamma+ lymphocytes were considerably enriched in cells having the characteristics of NK cells according to their phenotyping, morphology and NK cell activity, we may assume that NK cells have a low B:A ratio.

Antibodies, Monoclonal↗
PubMed1984

Enzyme analysis of autologous rosette-forming cells.

Autologous rosette-forming cells (ARFC) have been considered to be post-thymic precursor cells. Since thymocytes and peripheral T lymphocytes differ considerably in lactate dehydrogenase isoenzyme pattern and in activity of the enzymes of the purine metabolism, we investigated the enzyme profile in the ARFC. The L-lactate: NAD+ oxi-reductase analysis showed an isoenzyme pattern that closely resembled the pattern found in peripheral T lymphocytes and was totally different from the thymocytes. The levels of adenosine deaminase and purine nucleoside phosphorylase were identical to those found in the peripheral T lymphocytes and different from thymocytes. In our hands, the ARFC-enriched suspension contained predominantly OKT4+ and T mu+ lymphocytes. We propose that ARFC are a heterogeneous population encompassing all known subsets and cannot be considered a separate homogeneous entity.

Adenosine Deaminase↗
PubMed1984

Analysis of lymphocytes in tonsils and blood from patients with chronic tonsillitis.

A series of B, T and natural killer cell (NK) monoclonal antibodies was used to determine the distribution of lymphocyte subpopulations in cell suspensions obtained from tonsils of seventeen patients with chronic tonsillitis. The percentage of lymphocytes reacting with the monoclonal antibodies was determined by means of cytofluorometry. The majority of the tonsillar lymphocytes stained with the B-cell specific monoclonal antibody OKB-7. The T lymphocytes were composed of a majority of OKT4+ lymphocytes. Only a minority of the lymphocytes stained with the NK cell specific antibody Leu-7, whereas Leu-11b+ lymphocytes were virtually absent. In ten out of the seventeen patients T lymphocytes were purified from the tonsils and the blood and studied for the presence of the following activation antigens: OKT9, OKT10 and anti-HLA-Dr. These antigens were not detected on the membrane of these lymphocytes. This indicates that T lymphocytes activated in vivo express these antigens in a low amount.

Adolescent↗
PubMed1984

Association of anti-heart antibodies and circulating immune complexes in the post-pericardiotomy syndrome.

The post-pericardiotomy syndrome (PPS) is a common complication of cardiac surgery. In order to better understand the pathogenesis of this complication we undertook a prospective, triple blind study of consecutive long term survivors of cardiac surgery. We followed 82 patients and determined anti-heart antibodies (AHA), circulating immune complexes (CIC) and anti-viral antibodies (AVA) on sera pre-operatively and serially post-operatively. According to the clinical features of pericarditis, fever and leucocytosis, patients were divided into three groups: (1) complete PPS with all three symptoms, (2) incomplete PPS with two symptoms and (3) no PPS with one or no symptoms. Clinical PPS was found in 16 patients (19.6%). All of these patients had positive AHA, 12 patients (75%) had increased CIC and five patients (31%) had a four-fold or greater rise in titre to viruses studied. Twenty-four patients (29.2%) had an incomplete PPS. It was accompanied by positive AHA in 17 patients (70.8%), increased CIC in 14 patients (58.3%) and a four-fold rise or greater in virus titre in seven patients (29.2%). No PPS was found in forty-two patients (51.2%). It was accompanied by positive AHA in eight patients (19%), increased CIC in 10 patients (24%) and a four-fold or greater rise in virus titre in 12 patients (28.6%). There was a good correlation between the presence of PPS, AHA, CIC and the type of operation. Heart valve replacement surgery was more frequently complicated by PPS. Development of post-operative AHA and increased CIC were also more frequently found. We found a good correlation between PPS, positive AHA and increased CIC. No correlation was found between PPS and virus serology.

Adult↗
PubMed1983

Cell-marker studies in CLL with monoclonal OKT antisera and lactic dehydrogenase isoenzyme analysis.

In 16 patients with B-type CLL, the T and B cell compartment was analysed using the monoclonal anti-T-cell antisera OKT1, 3, 4 and 8 and the lactic dehydrogenase enzyme marker. Pertinent findings were: the presence on the CLL cells in 15 out of 16 patients of the antigen determined by the OKT1 antiserum, and, in all patients, a lower total LDH content on a per cell basis combined with a higher percentage-activity in the LDH-3 band as compared to the normal B-cell. Furthermore, the T-cell compartment was also disturbed in these patients, as the ratio of OKT4+ to OKT8+ cells was significantly depressed accompanied by a significant decrease of the LDH-1 percentage-activity in favour of LDH-3 and 4. These findings argue for the B-cell being immature and confirm the recent evidence that the T-cell compartment is changed in B-CLL.

Antibodies, Monoclonal↗
PubMed1982

Influence of nandrolone decanoate on the repopulation of the thymus after total body irradiation of mice.

It has been reported that nandrolone decanoate is helpful in overcoming the neutropenic phase following irradiation. In the present study the influence of nandrolone decanoate on the thymus' cellularity after total body irradiation was investigated. In comparison with a placebo-treated group, mice receiving nandrolone decanoate showed a similar pattern of thymus repopulation, but a significantly lower number of thymocytes over the whole period of treatment was found. Nonirradiated mice also had a significantly lower number of thymocytes when treated with nandrolone decanoate. In addition, the number of circulating leukocytes was also evaluated over a period of 1 month after total body irradiation. On 11 of the 21 days investigated, a significantly higher number of leukocytes was found in the nandrolone decanoate-treated group. We conclude that the action of nandrolone decanoate was not clearly distinct from that of testosterone regarding either granulopoiesis or thymic involution.

Animals↗
PubMed1980

Immunohistochemical evidence for a plasma membrane localization of dopamine-beta-hydroxylase in the mouse neuroblastoma.

Dopamine-beta-hydroxylase (D beta H), a glycoprotein enzyme which converts dopamine into noradrenaline, was purified from C1300 mouse neuroblastoma and used to raise antibodies in rabbits. Using an indirect immunofluorescence technique the cellular localization of D beta H in C1300 mouse neuroblastoma was compared with that of the superior cervical ganglion. C1300 neuroblastoma D beta H was found to be predominantly localized in the plasma membrane, in contrast to its intracellular localization in the superior cervical ganglion of A/J mice. At least part of the enzyme was found to be associated with the external side of the plasma membrane.

Animals↗
PubMed1979

Lactate dehydrogenase isoenzyme pattern of the pre-thymic precursor cell.

The thymic cell precursor was obtained from thymic rudiments of 14 day old mouse embryos of strain NMRI. The LDH isoenzyme pattern of this cell population showed a higher LDH-5 activity than the cortical and medullary thymocytes. These results indicate that during the T-cell development, a shift in the pattern occurs towards the LDH-1 end of the spectrum, as described for other murine tissues and cells. As cortical thymocytes contain less LDH-5 activity than the medullary thymocytes, however, the outcome of the latter cells from the former is in conflict with the shift toward the LDH-1 end of the spectrum. On the contrary a relationship whereby cortical and medullary thymocytes are independently derived from the thymic cell percursor, is consistent with the shift toward LDH-1.

Animals↗
PubMed1978

Lactate dehydrogenase isoenzyme pattern: marker for differentiation of lymphocytes.

The lactate dehydrogenase isoenzyme pattern has been determined in different murine thymocyte cell populations. Enrichment of thymocytes with more mature cells through total irradiation results in a smaller percentage of LDH-1, LDH-2, LDH-3 and a greater percentage of LDH-4 and LDH-5. Fractionation of normal thymocytes by velocity sedimentation at unit gravity yields a fraction of cells with a high sedimentation rate. LDH-1 and LDH-2 formed a smaller percentage of the total enzyme activity in these cells. These findings indicate that the LDH isoenzyme distribution is a marker for differentiation of thymocytes.

Animals↗