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Biomedical subjects

J P Berry

Publications and source records attributed to J P Berry.

At least 19 recordsLinked to original sources
PubMed2002

Are Pfiesteria species toxicogenic? Evidence against production of ichthyotoxins by Pfiesteria shumwayae.

The estuarine genus Pfiesteria has received considerable attention since it was first identified and proposed to be the causative agent of fish kills along the mid-Atlantic coast in 1992. The presumption has been that the mechanism of fish death is by release of one or more toxins by the dinoflagellate. In this report, we challenge the notion that Pfiesteria species produce ichthyotoxins. Specifically, we show that (i) simple centrifugation, with and without ultrasonication, is sufficient to "detoxify" water of actively fish-killing cultures of Pfiesteria shumwayae, (ii) organic extracts of lyophilized cultures are not toxic to fish, (iii) degenerate primers that amplify PKS genes from several polyketide-producing dinoflagellates failed to yield a product with P. shumwayae DNA or cDNA, and (iv) degenerate primers for NRPS genes failed to amplify any NRPS genes but (unexpectedly) yielded a band (among several) that corresponded to known or putative PKSs and fatty acid synthases. We conclude that P. shumwayae is able to kill fish by means other than releasing a toxin into bulk water. Alternative explanations of the effects attributed to Pfiesteria are suggested.

Animals↗
PubMed1997

Role of alveolar macrophage lysosomes in metal detoxification.

The intracellular behaviour of different toxic mineral elements inhaled as soluble aerosols or as insoluble particles was studied in the rat by electron microscopy, electron probe microanalysis, and electron microdiffraction. This study showed that, after inhalation, aerosols of soluble elements like cerous chloride, chromic chloride, uranyl nitrate, and aluminium chloride, are concentrated in the lysosomes of alveolar macrophages and are precipitated in the lysosomes in the form of insoluble phosphate, probably due to the activity of acid phosphatase (intralysosomial enzyme). Also, after inhalation of crystalline particles that are insoluble or poorly soluble in water such as the illites (phyllosilicates), ceric oxides (opaline), and industrial uranium oxides (U3O8), the small crystals are captured by the alveolar macrophage lysosomes and transformed over time into an amorphous form. This structural transformation is associated with changes in the chemical nature of particles inhaled in the oxide form. Microanalysis of amorphous deposits observed after inhalation of uranium or ceric oxides has shown that they contain high concentrations of phosphorus associated with the initial elements cerium and uranium. These different processes tend to limit the diffusion of these toxic elements within the organism, whether they are inhaled in soluble form or not.

Aerosols↗
PubMed1997

Early ultrastructural lesions of apoptosis induced in vivo in two varieties of tissues (thymus and kidneys) after a single whole-body-gamma irradiation of adult mice.

Three groups of adult Swiss albino female mice with an average body weight of 20 grams were exposed to a whole-body irradiation by 137-cesium gamma rays at 2, 4 and 6 Gy (1.4 Gy/min.). For all groups, samples of thymus and kidney were taken 15 min., 2, 6 and 24 hrs. after irradiation and immediately prepared for observation by electron microscopy. In the thymus the earliest significant ultrastructural lesions are observed in the nuclei from the fifteenth minute. These lesions are characterized by condensation of chromatin, convolution and fragmentation of nuclei. Alteration of mitochondria and clarification of cytoplasm in a number of thymocytes are also observed depending on the dose of radiation. These lesions increased according to the length of the post-irradiation period and after six hrs. a great number of macrophages are observed in the thymus. Most often a single macrophage, contain several apoptotic thymocytes, with a maximum number up to eight. In the kidney, serious lesions were observed, affecting both, the nucleus and the cytoplasm of the proximal convoluted tubule cells (PCT). However in these cells, the most significant and earliest lesions consist of wide cytoplasmic clarifications, severe mitochondrial damages, associated with architectural modifications of the brush border and the beta-cytomembranes. These damaged cells have been observed to occur close to normal ultrastructural cells. Less significant ultrastructural alterations are also noticed in different varieties of glomerular cells. In contrast to the serious lesions of the PCT and glomerular cells, no ultrastructural alteration were observed in the distal tubule.

Animals↗
PubMed1996

[Early ultrastructural lesions of kidney cells after intravenous administration of 239 plutonium citrate in rats].

After intravenous administration of (5 x 2.3 kBq and 5 x 9.25 kBq) plutonium citrate in adult male Sprague Dawley rats, their kidneys are withdrawn and prepared for observation under a transmission electron microscope. Seven days after the first injections, deep cellular alterations are observed in the proximal convoluted tubules. These alterations are mainly mitochondrial. The affected mitochondria are of swollen aspect and have their cristae partially or completely destroyed. Nevertheless within the same tubule we observe non altered cells directly in contact with deeply altered cells. In all the cases the lysosomes of the altered cells appear to be perfectly normal. The cell nuclei are mostly unaltered but a few cases of nuclear fragmentation exist. We also notice some architectural modifications in the brush border and in the betacytomembranes of the proximal convoluted tubule. Equally important mitochondrial alterations are also noticed in the different varieties of glomerular cells. We observe no other glomerular alterations. The major subcellular alterations in the proximal convoluted tubules and in the different varieties of glomerular cells deeply contrast with the distal convoluted tubules which are found to be totally unaltered. These mitochondrial alterations may be due to the alpha particle disintegration of plutonium which may either directly react with the mitochondria or, through the products of radiolysis of water react with the mitochondria respiration process. However the direct chemotoxicity of plutonium cannot be neglected.

Animals↗
PubMed1996

The role of lysosomes in the selective concentration of mineral elements. A microanalytical study.

The role of the lysosome during the intracellular concentration of diverse mineral elements has been evidenced by the electron probe X-ray microanalysis (EPMA). This highly sensitive technique allows an in situ chemical analysis of any chemical element with an atomic number greater than 11, present in ultra-thin tissue sections. Therefore, it has been demonstrated by using this EPMA that 21 out of the 92 elements of the periodic table, once injected in a soluble form, were selectively concentrated within lysosomes of several types of mammalian cells. Amongst these 21 elements, 15 are concentrated and precipitated in an insoluble from in association with phosphorus whereas the other 6 are precipitated in association with sulphur. Amongst the 15 elements which precipitate with phosphorus in lysosomes, there are: 3 group IIIB elements of the periodic system, (aluminium, gallium and indium); the rare-earth elements (cerium, gadolinium, lanthanum, thulium and samarium); 2 group IVA elements (hafnium and zirconium), two actinides (uranium and thorium) and elements such as chromium and niobium. The 6 elements which precipitate with sulphur comprise the 3 group VIII elements of the classification (nickel, palladium, platinum) and the 3 group IB elements (copper, silver and gold). The mechanisms responsible for this selective concentration involve enzymatic processes and predominantly acid phosphatases for elements precipitating as phosphates and arylsulfatases for elements precipitating with sulphur.

Cell Compartmentation↗
PubMed1996

Role of alveolar macrophages in the dissolution of two different industrial uranium oxides.

This study was aimed at assessing and understanding some mechanisms involved in the intracellular particle transformation of two uranium oxides (U3O8 and UO2 + Umetal) produced by a new isotopic enrichment plant using laser technology. Instillations were conducted on rats with both uranium compounds and alveolar macrophages were harvested at different dates and prepared in order to be studied using transmission electron microscopy and electron energy loss spectrometry (EELS). The presence of particles in the cells was observed from the first day after instillation, and crystalline needles of uranyl phosphate appeared in the cytoplasm of the cells. These needles were more numerous after instillation with the mixture UO2 + Umetal than after administration of U3O8 and may be correlated with the higher solubility of UO2 + Umetal observed in vitro. The formation of insoluble needles in lysosomes is consistent with the insolubilisation of uranium observed after phagocytosis by alveolar macrophages.

Air Pollutants, Occupational↗
PubMed1996

Intranuclear dense bodies after metal intoxication: a review of ultrastructural and microanalytical findings.

Abnormal intranuclear dense bodies are observed in several varieties of cells after intoxication by four varieties of metals: lead, bismuth, beryllium and neptumium. These inclusions have been studied by two microanalytical methods: Electron probe X-ray microanalysis (EPMA) and ion microscopy. A strong similarity has been observed in the ultrastructure of the dense bodies produced several weeks after beryllium and neptunium intoxication although there exists an important discrepancy between both elements concerning their physical, chemical and physico-chemical characteristics. Furthermore, these dense bodies are observed in the same varieties of cells (tubular proximal cells of kidneys, hepatocytes, pneumocytes). Intranuclear dense bodies produced by lead are also observed in the same types of cells, where they showed similar ultrastructure patterns as beryllium and neptunium inclusions but only after a long period, several years, after a chronic intoxication. The ultrastructure of the dense bodies produced by bismuth are clearly distinct from beryllium, neptunium or lead inclusions. Beryllium, neptunium and lead have been detected by EPMA or ion microscopy in the corresponding dense bodies although the real presence of bismuth remains to be confirmed in the nuclear dense bodies produced by this element.

Animals↗
PubMed1996

Subcellular localization of neptunium-237 in lung and kidney after intratracheal administration in the rat: an ultrastructural and microanalytical study.

Chronic intratracheal administration of 237Np to rate was performed during 6 weeks. The total dose administered was 45.8 kBq. Two methods, electron microscopy and electron probe X-ray microanalysis, were used to determine the intracellular sites of localization of 237Np. Clusters of dense granules were observed in nuclei of pneumocytes and proximal tubular cells of the kidneys. These clusters have been shown to contain neptunium associated with phosphorus, sulfur and calcium. Alterations of nuclei and ultrastructural cytoplasmic lesions were observed. The absorbed doses in lungs and kidneys were very low. These results suggest that the chemical toxicity of 237Np is more important than its radiological toxicity.

Animals↗
PubMed1995

Intranuclear sites of Np 237 in mammalian cells: a study using electron microscopy and electron probe microanalysis.

Two methods, electron microscopy and wavelength dispersive electron probe microanalysis, were used to determine the intracellular sites and chemical form of concentrations of neptunium nitrate 237 after chronic intoxication by the intraperitoneal route in two organs in the rat known to concentrate this element (kidney, liver). Abnormal intranuclear formations in the form of clusters of dense granules containing neptunium, phosphorus, sulphur, and calcium were found in the nuclei of kidney proximal tubule cells and hepatocytes. These formations had a maximum diameter of the order of 2 microns and were located in the central part of the nucleus, away from the nucleolus and peripheral chromatin. Serious nuclear and cytoplasmic ultrastructural lesions are often associated in cells containing neptunium inclusions. The absorbed doses in the kidney and the liver were very low. A relationship between these abnormal intranuclear structures and the carcinogenic effect of neptunium remains to be clarified. This effect is related more probably to the chemical toxicity of Np 237.

Animals↗
PubMed1995

Interaction of selenium with copper, silver, and gold salts. Electron microprobe study.

The interaction of selenium with elements of group 1b of the periodic system, i.e. copper, silver, and gold was studied. Electron probe microanalysis was used to detect elements in intracellular organelles. Administration of copper, silver, or gold salts (the latter being used in chrysotherapy) showed that these elements were concentrated in the lysosomes of the liver or kidney in the presence of sulfur. Silver salts were also precipitated in glomerular basement membranes. The action of selenium enhances this intralysosomal process of concentration and precipitation. Sulfur and selenium are detected in the lysosome and this makes identification of the precipitate difficult. The action of selenium, which consists in removing toxic elements from the systemic circulation and concentrating them in the lysosomes, is in most cases beneficial for the organism. This mechanism, which has already been studied for arsenic, is extended in this study to other elements.

Animals↗
PubMed1995

Scanning ion microscopy mapping of basement membrane elements and arterioles in the kidney after selenium-silver interaction.

The effects of selenium and silver salts was studied by scanning ionic microscopy during experimental argyria mapping of the different basement membrane elements. The ionic microscope (IMS 4F) was equipped with a high resolution spectrometer giving high spatial resolution on the image obtained. After long-term treatment with silver salt alone, silver and sulphur deposits were observed in the membranes. After administration of selenium and silver salt, it was possible to map nitrogen, sulphur, selenium and silver to the glomerular basement membrane as well as to the wall of the kidney arterioles. In the latter, sulphur, selenium and silver were localized only in the elastic laminae of the walls. This process of precipitation of silver deposits in the membrane can be interpreted as process of selenium "detoxification" of the organism.

Animals↗
PubMed1995

Subcellular localization of gadolinium injected as soluble salt in rats: a microanalytical study.

The rare earth gadolinium (Gd) is used in modern industry. Solubilized DTPA Gd and DOTA Gd complexes are used as contrast media in nuclear magnetic resonance imaging. In order to determine the subcellular localization of Gd, rats were injected intraperitoneally with Gd nitrate. Two microanalytic methods, ion microanalysis and electron microprobe, enabled the distribution and the intracellular localization of Gd to be determined in the liver, spleen, bone marrow, kidneys and lung. The results showed: a) a punctual distribution of Gd in the tissues (liver, spleen, bone marrow and lung) as observed by ion microscopy; b) a selective concentration of Gd in the lysosomes of macrophages of the liver (hepatocytes), spleen (macrophages), bone marrow (macrophages) and lung (phagocyte cells), as determined by electron probe X-ray microanalysis. In all these sites the Gd is associated to phosphorus. Results are compared to those found for other rare earths and metal elements.

Animals↗
PubMed1994

Advantages of the scanning ion microscopy for mapping halogen corticoids in normal and transformed cells in culture.

The intra-cellular distribution of eight halogen glucocorticoids was investigated by ion microscopy in two cellular varieties of cultured non-cancer cells (fibroblast 3T3) and cancer cells (human breast tumor cells MCF-7). Two types of ion microscopy helped to determine this distribution, a direct imaging ion microscope (SMI 300) with low spatial resolution, and a scanning ion microscope (IMS4F), featuring high resolution, serving to obtain maps representing the intra-cellular distribution of the fluorine elements and drugs present in these monolayer cultured cells. The fluorine images representative of the drugs containing fluorine showed that these drugs are essentially concentrated in the cell nuclei. In these nuclei, the distribution of these drugs is different from that of heterochromatin and of the nucleolus.

3T3 Cells↗
PubMed1994

Detection and cartography of the fluorinated antimalarial drug mefloquine in normal and Plasmodium falciparum infected red blood cells by scanning ion microscopy and mass spectrometry.

Due to the presence of fluorine atoms in its molecule, the antimalarial drug mefloquine (MQ) can be easily detected in normal and Plasmodium falciparum infected red blood cells (RBC) by scanning ion microscopy and mass spectrometry. The P falciparum infected RBC exhibited intense distribution of MQ inside the parasite. The main compartments of the parasite which accumulate the drug were the food vacuole and the cytoplasm. The correlation between fluorine (19F-) and phosphorus (31P-) as well as probes for the DNA synthesis (BrdU and IdU) emissions shows that the parasite nucleus is also accessible to the drug. This study demonstrates that SIMS technique on smear preparations is an efficient approach for the direct detection and cartography of fluorinated antimalarial drugs in normal and P falciparum infected RBC, without radioactive labelling.

Animals↗
PubMed1994

Subcellular localization of gold in suprarenal testicle and thyroid glands after injection of allochrysine in rats.

Gold injected under the form of anti-rheumatoid polyarthritis soluble solutions provokes, as observed by electron microscope, a deposit of crystalline micro-needles in different tissues, like in cells of adrenal and suprarenal glands, in Leydig cells of the testicles, in isolated thyrocytes and in thyroid endothelial cells. They are present as bundles, often of incurvated type, of high electron-density, present in lysosomes, which contain moreover a hyaline, emptied vesicle. These structures are named "aurosomes". The microanalysis, using the MS 46 (Cameca) and the Camebax (MBX) demonstrates that these crystalline structures are composed by gold associated with sulphur, and not with phosphate.

Animals↗
PubMed1994

Selenium-arsenic interaction in renal cells: role of lysosomes. Electron microprobe study.

Selenium can modify the toxicity of different elements. Selenium and the element form a complex that is precipitated in the tissues and inhibits the toxicity of the element. We studied the interaction of arsenic and selenium at the subcellular level in rat kidney cells using electronic probe microanalysis that permits detection of elements in the intracellular organelles. This showed that arsenic and selenium are concentrated and precipitated in the lysosomes of the renal cells in the form of insoluble selenide (As2Se). In the long term, the lysosomes and their precipitate are eliminated in the urine. These processes enable the lethal toxicity of arsenic to be inhibited. This intralysosomal concentration and precipitation can serve as a model for the mechanism of interaction of selenium with other elements and can be compared with other mechanisms of concentration and precipitation of elements in the lysosomes.

Animals↗