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P Martin

Publications and source records attributed to P Martin.

At least 901 records · Page 50Linked to original sources
PubMed1983

The surface antigen profile of HEL cells.

The surface antigen profile of HEL cells was probed with a panel of monoclonal antibodies that have been associated with various hemopoietic lineages. Although the list of antibodies tested is by no means complete, the following characteristic picture emerges. a. Affiliation of HEL cells with erythroid lineage has been secured by other than the globin criteria. In this respect differences with K562 cells have been mostly of a quantitative nature, with only a few exceptions. One notable exception is the presence of group H determinant in HEL cells. b. There is a strong expression in HEL cells of determinants present in the platelet/megakaryocytic series. K562 cells express only selective determinants for this lineage. c. In contrast to K562 cells, there is a strong expression in HEL cells of monocyte-associated determinants. Corroborating this are the cytochemical properties of the HEL cells [11] and their induction by TPA (12-0-tetradecanoyl-phorbol-13-acetate) to a macrophage-like phenotype [41]. d. Granulocyte-specific antigens have not been found in HEL cells, although shared antigenic determinants of granulocytes with other cells can be expressed. In contrast, K562 cells display several granulocyte-specific antigens. e. No T-cell-associated antigens are found in HEL cells, although some B-cell-associated determinants can be detected. The interpretation of the composite phenotype in HEL cells is, as yet, unclear. One fact stands out, however; the only two erythroid-associated lines available today also display a multilineage-affiliated phenotype that seems to have no parallel with the other cell lines thus far described.

Antigens, Surface↗
PubMed1982

[Osteogenic sarcomas of the limbs. Radical treatment of the primary tumor: choosing between irradiation and amputation ].

In osteogenic sarcomas of the extremities, radical therapy of the primary tumor now seems more precisely delineated. In most cases, especially in large tumors with lytic lesions or fractures, and in children. Irradiation is indicated only in small tumors with condensation, and in tumors of the proximal metaphysis of the humerus. Conservative surgical treatment with carcinologically satisfactory resection of involved bone followed by reconstruction, is currently under evaluation. Such treatment is indicated in specific cases: children in the final stage of growth, and small tumors without major involvement of soft tissues that respond to preoperative chemotherapy.

Adolescent↗
PubMed1982

Human large-bowel cancer: correlation of clinical and histopathological features with banded chromosomes.

Clinical and histopathological features were correlated with cytogenetic banding studies on direct preparations from 31 large-bowel tumors. An interesting relationship between the site and the karyotypes of the tumors was observed. There appears to be a progressive increase in chromosomal number and/or structural rearrangement as one progresses from proximal to distal large bowel. We suggest that these observations may be related to differences in function and micro-environment within different areas of the colon. Although it is not known what factors favor cytogenetic variability and instability on the left side or the presence of fewer abnormalities on the right side of the colon, it is evident that clonal karyotypic evolution may be important in the progression of large-bowel cancer. The brevity of follow-up precludes conclusions regarding the influence of karyotype on survival.

Cecal Neoplasms↗
PubMed1982

HEL cells: a new human erythroleukemia cell line with spontaneous and induced globin expression.

A new human erythroleukemia cell line has been established. This line, designated HEL, is capable of spontaneous and induced globin synthesis, producing mainly G gamma and A gamma chains. Embryonic chains (epsilon, zeta) and alpha chains are detectable in very small amounts; beta chains are undetectable. This line provides a new model system for studying aspects of erythroid cell differentiation and differential globin gene expression.

Cell Line↗
PubMed1982

[Costal stapling in severe thoracic traumas (author's transl)].

Thirty-two of 320 patients with severe thoracic trauma were treated with costal stapling. The technique, described by R. Judet in 1973, is basically simple but sometimes difficult to perform. In the most favourable cases (here 23/32 patients), it avoids tracheostomy and its complications and reduces the restrictive sequelae associated with pleural adhesion or thoracic wall deformities. In addition, active respiratory physiotherapy can be undertaken at an earlier stage. The authors describe the indications and limitations of this treatment on the basis of the results obtained in this series.

Adolescent↗
PubMed1982

[Cerebral ischemia after ligature of both carotid arteries in rats: effect of ginkgo biloba extracts (author's transl)].

Simultaneous ligature of both carotid arteries in Long Evans rats results in death for all animals. 50% of the animals survive if the ligatures are separated by a four-day interval. Studies of variations in cerebral blood flow according to the time interval between the two ligatures show that alternative vascularization develops and that the balance between both hemibrains is restored. After giving L-dopa3H to animals with ligature of both carotids, increased synthesis of cerebral dopamine 3H and norepinephrine 3H can be demonstrated. When animals are given extracts of Ginkgo biloba leaves prior to carotid ligatures, survival rate is improved and dopamine synthesis increased, without marked changes in cerebral blood flow. This is related to increased brain cell activity in spite of hypoxia due to carotid ligature.

Animals↗
PubMed1982

The lactation-blocking drug bromocriptine and its application to studies of weaning and behavioral development.

An experimental method for blocking maternal lactation is reviewed and the possible application of this technique for experimentally manipulating weaning is considered. Maternal milk production can be inhibited using the prolactin-suppressing drug bromocriptine. The suitability of bromocriptine for use in behavioural experiments is considered. The pharmacology of bromocriptine (CB 154) is briefly outlined and a compilation of the reported lactation-inhibiting doses for various species is presented. The possible endocrine and behavioral side-effects and the toxicity of the drug are discussed. It is concluded that, in most species studied so far, the drug is relatively free from significant side-effects at the low doses needed to suppress lactation. Guidelines for the practical use of bromocriptine are suggested. Finally, some ideas about the possible application of the drug to the study of behavioral development and parent-offspring relationships are discussed.

Animals↗
PubMed1982

Huntington's disease - imbalance of free amino acids in the cerebrospinal fluid of patients and offspring at-risk.

A total of 27 different amino acids were determined in the fasting, morning lumbar CSF of 12 patients with Huntington's Disease (HD), 8 at-risk offspring and 16 non-choreic control patients. A significant (P less than 0.001) decrease was observed for asparagine, isoleucine, leucine, phenylalanine, histidine, arginine, alpha-aminoadipic acid and homocarnosine in patients with HD compared to the non-choreic controls. Only tyrosine was increased in HD. These alterations were to an extent more pronounced in 5 neurophysiologically conspicuous offspring. The alterations suggest that amino acid imbalance is an early metabolic disturbance in HD.

Amino Acids↗
PubMed1982

Karyotypic findings in a colonic villous adenoma.

Chromosomes from a patient with a villous adenoma of the colon were examined in detail with fluorescent banding. Of the cells analyzed, 73% had a modal chromosomal number of 48-52. The karyotypic findings show clonal evolution, an additional chromosome #8 being the most frequent abnormality, suggesting that this may be the primary chromosomal change, but other changes such as loss of a Y chromosome and the presence of marker chromosome #1 with duplication of the long arm also were observed. Previous cytogenetic data on large-bowel tumors is summarized. We hypothesize that this chromosomal evidence suggests that tubular adenoma, villous adenoma, and adenocarcinoma may be interrelated steps of a growth disorder.

Adenoma↗
PubMed1982

Study of the heterogeneity of bovine pepsin A by pseudo isoelectric focusing.

Pseudo isoelectric focusing (PIEF), i.e. focusing stopped before the equilibrium is reached, has been successfully applied to analyse bovine pepsins A obtained from abomasum mucosa extracts and from 3 individual abomasal juices. Whole bovine pepsin A from mucosa extracts, was resolved in PIEF, using an acidic pH gradient(2-4), into five major and active components. Its fractionation on hydroxyapatite only gave four components which were not homogeneous in PIEF, suggesting that interactions between the different components occur during the chromatographic procedure. After treatment with potato acid phosphatase, whole bovine pepsin A showed only one band in PIEF, displaying enzymic activity and with a mobility identical to that of the less anodic band in untreated pepsin. These results, together with organic phosphate determinations, obviously confirm that the heterogeneity of bovine pepsin A is due to the phosphate content which appears to range between 0 and 3 mol./mol. for the 5 components. Two of them, the phosphate content of which appears to be 1 mol./mol., seem to differ in the location of this phosphate group in the molecule. Whole bovine pepsin A preparations from abomasal juices shared the same pattern in PIEF, identical to that observed with bovine pepsin A from mucosa extracts, thus excluding that dephosphorylation might be involved in the secretory process, as well as disproving the theory that dephosphopepsinogen might be an intermediate in the synthesis of pepsinogen, as it was previously suggested.

Abomasum↗
PubMed1982

Fade of cardiac responses during tonic vagal stimulation.

We applied trains of stimuli to the vagosympathetic trunks of anesthetized dogs and studied the time courses of the resultant chronotropic and inotropic responses. These responses were maximum soon after the onset of the test stimulus train but then declined over the next 1-5 min despite continued stimulation. The fade ratio was defined as the magnitude of this decline divided by the magnitude of the maximum response. For both inotropic and chronotropic responses, maximum increased with stimulation frequency, but the fade ratio did not change. In some experiments, conditioning stimulus trains of variable duration were applied before a standard rest period, after which the test stimulus train was applied. The longer the conditioning period, the lower was the subsequent fade ratio of the inotropic responses to the test stimulation train. In other experiments, a conditioning train of 2 min was applied, and then variable rest periods were interposed before the test train was applied. The longer the rest period, the greater were the subsequent maximum and fade ratios of the inotropic responses to the test stimulus train. These results indicate that some factor persists well after the cardiac responses to a given stimulus, and this factor affects the next response to an identical vagal stimulation. The chronotropic responses faded about three times faster than the inotropic responses. Thus different mechanisms may account for the fade of the inotropic and chronotropic responses.

Animals↗