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Biomedical subjects

H Planel

Publications and source records attributed to H Planel.

At least 37 records · Page 2Linked to original sources
PubMed1984

Changes in developmental capacity of artemia cyst and chromosomal aberrations in lettuce seeds flown aboard Salyut-7 (Biobloc III experiment).

This paper gives the results of investigations performed on the first container (A) of the Biobloc III experiment, flown aboard the orbital station Salyut 7 for 40 days. The space flight resulted in a decreased developmental capacity of Arterlia cysts, hit or not hit by the HZE particles. No effect was observed in cysts in bulk. A synergetic effect of microgravity and gamma pre irradiation is described. The germination of in-flight lettuce seeds was decreased. The space flight resulted also in a higher percentage of cells with chromosomal aberrations. Relations between biological response, TEL and location of HZE particles are discussed.

Animals↗
PubMed1984

Effects of gravity and cosmic rays on cell proliferation kinetics in Paramecium tetraurelia.

Space flights resulted in a stimulating effect on kinetics of proliferation in Paramecium tetraurelia. Additional experiments were performed in order to determine the origin of this phenomena. Paramecia were cultivated in balloon flights or in a slow clinostat, or were exposed to different levels of hypergravity. The results suggest that changes in cell proliferation rate are related to cosmic rays and to a direct effect of microgravity.

Animals↗
PubMed1984

Ultrastructural investigations on two lymphoid cell lines from Niemann-Pick disease type B.

Lymphoid cell lines (LCL) were established by Epstein-Barr Virus (EBV) transformation of blood B-lymphocytes from two different patients affected with Niemann-Pick disease (NPD) type B. Those lines were severely deficient in sphingomyelinase activity (8% and 10% residual activity). Ultrastructural investigations showed in both these lines the presence of numerous osmiophilic, dense and pleiomorphic inclusions characteristic of lysosomal storage (due to the accumulation of amphiphilic lipids) similar to those observed in tissues from NPD.

Cell Line↗
PubMed1984

Morphologic, quantitative and cytoenzymologic studies of synoviocytic and monocytic cells in synovial fluid.

The findings are presented of a morphologic, quantitative, cytochemical and cytoenzymologic study of the mononucleated nonlymphoid cells in knee synovial fluids from osteoarthritis and various inflammatory diseases. The morphologic criteria allowed the identification of subtypes, including phagocytic subtypes, among synoviocytic and monocytic cells in the fluids. The quantitative study showed an important afflux of monocytes and a hyperexfoliation of synoviocytes in the inflammatory diseases. In fluids with intermediate cellularity, the ratio of monocytes to synoviocytes allowed the differential cytodiagnosis between osteoarthrosis and arthritis. All monocytic subtypes, especially the phagocytic one, were highly significantly increased in the inflammatory diseases. A lower increase was shown by the synoviocytic subtypes, except the phagocytic one, which was not changed. Giant multinucleated synoviocytes were found in every type of disease and thus do not constitute a cytodiagnostic marker. Alcian blue staining without hyaluronidase treatment showed hyaluronate in only a small percentage of the synoviocytes. Cytoenzymologic study showed that synoviocytes and monocytes were positive for all tested hydrolases (beta glucuronidase, acid phosphatase and alpha naphthyl acetate esterase), with the reactivities always higher in the synoviocytes. The synoviocytes were always negative with peroxidase, so this reaction, although it marks only a minority of the monocytic population, can be used as an extra cytologic criterion for the discrimination of mononucleated cells in synovial fluid. There was no significant quantitative difference at the cellular level between osteoarthrosis and arthritides in the reaction to these four enzymes. The lysosomal enzymatic activity in both monocytic and synoviocytic cells confirmed their heterophagic properties. However, synoviocytic heterophagy seems to be a physiologic process, either little or not affected by inflammatory events. On the other hand, monocytic heterophagy and then the macrophagic transformation of monocytes appears to be a major aspect of intrasynovial inflammatory reactions. The question remains as to why, if a large majority of exfoliated synoviocytes comes from type A synovial-lining cells and if they belong to mononuclear phagocytic system, do they so weakly, or not at all, participate as phagocytes in the inflammatory reaction.

Acid Phosphatase↗
PubMed1984

[Biological effects of weightlessness at the cellular level. Comparative study of cultures of Paramecia aboard the orbital station Salyut-6 and a stratospheric balloon].

In order to distinguish the effects of cosmic rays from those of weightlessness at the cellular level, we performed experiments aboard stratospheric balloon, where gravity is equal to 1 g and cosmic radiation roughly equal to that aboard Salyut-6. The results suggest that the stimulation of cell proliferation is probably due to cosmic rays, metabolic changes being related to microgravity.

Calcium↗
PubMed1984

[Non-lymphoid mononucleated cells in the synovial fluid in arthrosis and various inflammatory arthropathies. Morphologic, quantitative and cytoenzymologic study].

This paper describes a morphologic, quantitative, cytochemical study of mononuclear non lymphoid cells in knee synovial fluid in osteoarthritis and various arthritides. Morphologic criteria allow to identify among these cells various synoviocytic and monocytic subtypes with in both types, phagocytic subtypes. Quantitative study shows in arthritides an important afflux of monocytes and a hyperexfoliation of synoviocytes. In fluids with intermediate cellularity, Monocytes/Synoviocytes ratio allows the differential cytodiagnosis between osteoarthrosis and arthritis. All monocytic subtypes and especially the phagocytic one are highly significantly increased in arthritides. Synoviocytic subtypes show a lower increase, except the phagocytic one, which is not changed. Giant multinuclear synoviocytes are found in every type of disease and cannot constitute a cytodiagnosis marker. Alcian Blue and hyaluronidase treatment show hyaluronate in a few percentage of Synoviocytes. Cytoenzymologic study shows that synoviocytes and monocytes are positive in all tested hydrolases: beta Glucuronidase, Acid Phosphatase, alpha Naphthyl Acetate Esterase, these activities being always higher in synoviocytes. With peroxidase, synoviocytes are always negative, so this reaction although it marks only a minority of monocytic population can be used as an extra cytologic criterion for discrimination of mononuclear cells in synovial fluid. In these four enzymes there is no significant quantitative difference at cellular level between osteoarthrosis and arthritides. Lysosomal enzymatic activity in both monocytic and synoviocytic cells confirms their heterophagic properties. However synoviocytic heterophagy seems to be a physiological process not or few affected by inflammatory events. On the opposite, monocytic heterophagy and then macrophagic transformation of monocytes appears as a major aspect of intrasynovial inflammatory reaction. If a large majority of exfoliated synoviocytes comes from A type synovial lining cells and if they belong to Mononuclear Phagocyte System, why do they so weakly, or not, participate as phagocytes to inflammatory reaction.

Acid Phosphatase↗
PubMed1983

Results on Artemia cysts, lettuce and tobacco seeds in the Biobloc 4 experiment flown aboard the Soviet Biosatellite Cosmos 1129.

Artemia cysts, lettuce and tobacco seeds were flown aboard the Cosmos 1129 for 19 days. A correlative method was used in order to determine the passage of cosmic heavy ions (HZE particles) through the biological test objects. This space flight resulted in a decrease on hatchability, nucleic acid and protein synthesis in hydrated Artemia cysts. HZE particle effects on plant cellular chromosomes are confirmed. In tobacco seeds, a stimulating effect on germination rate and a higher frequency of abnormalities were observed. Dormant biological objects are a very suitable material to study cosmic ray effects: these objects can be arranged in monolayers and sandwiched between visual track detectors in order to determine the passage of the cosmic heavy ions (HZE particles). On the other hand this method allows us to study effects of microgravity and those of the protonic component of cosmic rays in the objects not hit by the HZE articles.

Animals↗
PubMed1983

Demonstration of a biological effect of natural ionizing radiations.

The blue-green alga, Synechococcus lividus, was grown under various levels of radiations. Shielding of cultures with lead resulted in a lower cell growth rate: the reduction disappeared when a normal radiation level was restored in the lead chamber. Irradiations from a thorium source at a dose-rate 14 times higher than that of natural irradiation stimulated the growth of the algae. These results are a new demonstration of a biological effect of background radiations.

Background Radiation↗
PubMed1983

[Ultrastructural study of the photoreceptors of the human retina during aging].

The ultra-structural study of the photoreceptors in the human retina during the aging process was carried out by comparing two groups of patient: 6 young subjects under 25 years of age, and 6 older subjects over 70. Retinal samples were taken from the posterior pole and treated with the classical techniques of electron microscopy. Our works show that during the aging process, nuclear and cytoplasmic morphological modifications are observed. The observation about nuclear modifications is in full agreement with aging process theories according to which the genome plays an essential part. On the other hand, no modification of the external article could be so far observed. Further works will perhaps allow to discover a decrease of the renewal process of the photoreceptor discs.

Adolescent↗
PubMed1983

[Ultrastructural aspects of the dormant Artemia embryo].

The ultrastructure of the Artemia cyst and larval organism was investigated. The morphology of the blastomere and of the cell organelles was described. Investigations showed the presence of two mitochondria populations: one located in the cytoplasm, the other one embedded inside the yolk platelets. Relations between yolk and mitochondria are more obvious when considering the first steps of embryonic development.

Animals↗
PubMed1982

[Comparative study of the proliferation of Paramecium tetraurelia aboard a satellite and aboard a stratospheric balloon].

A possible effect of cosmic rays on cell proliferation was investigated in cultures of Paramecium tetraurelia during a stratospheric balloon flight, with the techniques already used for the CYTOS experiments, performed aboard the orbital station Salyut 6. The results show that the stimulating effect of space on cell proliferation, reported in the CYTOS experiments, also occurs in the balloon flight. The respective roles of cosmic rays and weightlessness in the biological response are discussed.

Animals↗
PubMed1982

[Mononucleated phagocytes and mesothelial cells in serous peritoneal effusion fluid].

Twenty one peritoneal effusions from patients with cirrhosis were studied in order to characterize mesothelial cells, monocytes and their vacuolated forms. Morphological investigations were performed after Papanicolaou, M.G.G. and Giemsa stains; cytochemical studies by P.A.S., Alcian Blue pH 2,5 and Sudan Black B techniques. Seven enzymatic activities were appreciated: Naphtyl Acetate Esterase, Acid Phosphatase pH 5, beta Glucuronidase, Lactico-dehydrogénase, Malico D, NADH.D and Peroxidase pH 7,6. The free mesothelial cells show a metabolic and functional active phase in which their hydrolasic equipment suggests an intense lysosomal activity only correlated to pinocytosis. Monocytes in transudates show a morphologically micro-vacuolated macrophagic transformation of pinocytic type (elicited macrophages ?); they only become cytophagic when an acute inflammation occurs (activated macrophages ?). This paper emphasizes analogy of behaviour of mesothelial cells and monocytes in transudates, but demonstrates differences in their energetic metabolisms and endocytic characteristics.

Ascitic Fluid↗
PubMed1982

Effects of space flight factors at the cellular level: results of the Cytos experiment.

Paramecium tetraurelia was cultivated aboard the Soviet orbital station Salyut 6. Each culture included one cell, bacterized culture medium, and two small glass tubes filled with a fixative. Cultures were kept at a low temperature before Soyouz-Salyut docking. Cultures were maintained at 25 degrees +/- 0.1 degree C in orbit and were fixed every 12 h. The space flight resulted in an increase in cell growth rate and in cell volume. Measurements of cell dry weight and total protein content favour a higher cell water content. Respective roles of cosmic rays and microgravity are discussed. Cytos results are compared to those of previous space experiments.

Animals↗
PubMed1982

Proliferation kinetics of paramecium tetraurelia in balloon-borne experiments.

Experiments were carried out to demonstrate the effect of cosmic radiation, at a balloon-flight ceiling of about 36,500 m (120,000 ft) on single-cell organism proliferation. Paramecium tetraurelia were placed in air-tight containers and maintained at 25 degrees +/- 0.1 degrees C. Cellular growth was determined by cell count, either after recovery or during the flight, by means of an automatic fixation device. Dosimetry was performed by a tissue equivalent proportional counter and was of about 0.5 mrad/h. Flight ceiling duration ranged from 48 min - 22 h. A secondary stimulating effect of growth rate, preceded by a temporary decrease, was observed after recovery. Because of the high bacterial concentration in the trans-Mediterranean flight culture medium, the temporary drop of the growth rate, due to the radiolysis products, disappears. We consider that the stimulating effect can be the result of enzymatic intracellular scavenging of radiolysis products generated in the cell.

Altitude↗
PubMed1981

[Study of the intra- and extracellular electrolyte content in Paramecia cultures carried out during a space flight (author's transl)].

In the results of previous investigations we have already reported that cultures of Paramecium tetraurelia submitted to a space flight present a stimulation of their proliferative ability, an increase in cell volume and a decrease in dry weight and in total protein content. These results suggest changes of cell metabolism induced by the space environment. In order to confirm this hypothesis we have studied the concentration of extracellular electrolytes in the control and the in-flight culture media with respect to the intracellular content of the same electrolytes. These measures concern Na, Cl, K, P, Mg, Ca. In this paper we report the results of these analyses and note that if no differences are noted for Na and Cl between control and in-flight cultures, modifications in P, K, Ca and Mg levels are observed. Generally there is a higher concentration of these elements in the in-flight medium but, in contrast, a lower intracellular content is noted for in-flight Paramecia. We have established a double comparison: on the one hand between control and in-flight media and between control and in flight cells, on the other hand between media and cells. All these data suggest possible changes in the membrane permeability, or of the binding proteins in Paramecia cultivated in hypogravity.

Animals↗
PubMed1981

Effects of very low doses of ionizing radiation on the clonal life-span in Paramecium tetraurelia.

Effects of very low doses of ionizing radiation were investigated on life-span in Paramecium tetraurelia. After autogamy single cell cultures were place (1) in a control chamber with radiopermeable walls; (2) in a shielded device with 10 cm thick lead walls; (3) in a similar shielding device including a 60Co source giving a dose of 760 mrad per year at the culture level. Life-spans, expressed in days and in mean total number of fissions measured from autogamy to the death of all sublines, were about 200 fissions and 55 days in controls. Life-spans of shielded sublines were increased and lower life-spans were observed in both shielded and irradiated sublines. These findings provide new evidence for a biological effect of very low doses of ionizing radiations and show that fission potential of Paramecium tetraurelia can be affected by variations in the background radiation level.

Animals↗
PubMed1981

[Effects of small doses of ionizing radiation on embryonic development of the mouse].

Mice with vaginal plugs were irradiated, seven hours after mating, i.e near fecundation, by 5, 10 and 25 rads of gamma rays from a 60Co source. Females were sacrificed on the 18th day of gestation. The total number of implantations was unchanged after exposure to 5 and 10 rads but the frequency of resorptions was increased for all doses. No abnormalities were observed in testicles, kidneys and skeleton.

Abnormalities, Radiation-Induced↗