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1.
Persoonia ; 50: 48-122, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38567262

RESUMO

Type material and additional collections of 11 taxa of Gautieria described in Europe and North Africa have been studied, namely G. dubia, G. graveolens, G. morchelliformis var. globispora, G. morchelliformis var. magnicellaris, G. morchelliformis var. morchelliformis, G. morchelliformis var. stenospora, G. otthii, G. pseudovestita, G. retirugosa, G. trabutii and G. villosa. At the same time, morphological and genetic studies on recent and herbarium collections from several European countries have been carried out. This enabled clarification of sections within Gautieria and differentiation of 28 taxa, of which 21 are new to science. However, the deeper relationships and nomenclature changes related to the phylogenetic position of the genus Gautieria within Gomphaceae will not be addressed in this study because they would require a more complete molecular analysis together with that of related genera, e.g., Gomphus, Turbinellus, and the four subgenera of Ramaria. In addition, a lectotype for G. villosa var. villosa and reference specimens for G. graveolens and G. morchelliformis var. morchelliformis are selected, and the new combination G. morchelliformis var. dubia is proposed. Detailed descriptions, macro- and microphotographs and distribution maps of all taxa are provided, as well as extensive information on their ecology, chorology and phylogeny. A key is included to facilitate identification of taxa. Citation: Vidal JM, Cseh P, Merényi Z, et al. 2023. The genus Gautieria (Gomphales) in Europe and the Mediterranean Basin: a morphological and phylogenetic taxonomic revision. Persoonia 50: 48 -122. https://doi.org/10.3767/persoonia.2023.50.03.

2.
Persoonia ; 48: 261-371, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38234686

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Australia, Agaricus albofoetidus, Agaricus aureoelephanti and Agaricus parviumbrus on soil, Fusarium ramsdenii from stem cankers of Araucaria cunninghamii, Keissleriella sporoboli from stem of Sporobolus natalensis, Leptosphaerulina queenslandica and Pestalotiopsis chiaroscuro from leaves of Sporobolus natalensis, Serendipita petricolae as endophyte from roots of Eriochilus petricola, Stagonospora tauntonensis from stem of Sporobolus natalensis, Teratosphaeria carnegiei from leaves of Eucalyptus grandis × E. camaldulensis and Wongia ficherai from roots of Eragrostis curvula. Canada, Lulworthia fundyensis from intertidal wood and Newbrunswickomyces abietophilus (incl. Newbrunswickomyces gen. nov.) on buds of Abies balsamea. Czech Republic, Geosmithia funiculosa from a bark beetle gallery on Ulmus minor and Neoherpotrichiella juglandicola (incl. Neoherpotrichiella gen. nov.) from wood of Juglans regia. France, Aspergillus rouenensis and Neoacrodontium gallica (incl. Neoacrodontium gen. nov.) from bore dust of Xestobium rufovillosum feeding on Quercus wood, Endoradiciella communis (incl. Endoradiciella gen. nov.) endophytic in roots of Microthlaspi perfoliatum and Entoloma simulans on soil. India, Amanita konajensis on soil and Keithomyces indicus from soil. Israel, Microascus rothbergiorum from Stylophora pistillata. Italy, Calonarius ligusticus on soil. Netherlands, Appendopyricularia juncicola (incl. Appendopyricularia gen. nov.), Eriospora juncicola and Tetraploa juncicola on dead culms of Juncus effusus, Gonatophragmium physciae on Physcia caesia and Paracosmospora physciae (incl. Paracosmospora gen. nov.) on Physcia tenella, Myrmecridium phragmitigenum on dead culm of Phragmites australis, Neochalara lolae on stems of Pteridium aquilinum, Niesslia nieuwwulvenica on dead culm of undetermined Poaceae, Nothodevriesia narthecii (incl. Nothodevriesia gen. nov.) on dead leaves of Narthecium ossifragum and Parastenospora pini (incl. Parastenospora gen. nov.) on dead twigs of Pinus sylvestris. Norway, Verticillium bjoernoeyanum from sand grains attached to a piece of driftwood on a sandy beach. Portugal, Collybiopsis cimrmanii on the base of living Quercus ilex and amongst dead leaves of Laurus and herbs. South Africa, Paraproliferophorum hyphaenes (incl. Paraproliferophorum gen. nov.) on living leaves of Hyphaene sp. and Saccothecium widdringtoniae on twigs of Widdringtonia wallichii. Spain, Cortinarius dryosalor on soil, Cyphellophora endoradicis endophytic in roots of Microthlaspi perfoliatum, Geoglossum lauri-silvae on soil, Leptographium gemmatum from fluvial sediments, Physalacria auricularioides from a dead twig of Castanea sativa, Terfezia bertae and Tuber davidlopezii in soil. Sweden, Alpova larskersii, Inocybe alpestris and Inocybe boreogodeyi on soil. Thailand, Russula banwatchanensis, Russula purpureoviridis and Russula lilacina on soil. Ukraine, Nectriella adonidis on overwintered stems of Adonis vernalis. USA, Microcyclus jacquiniae from living leaves of Jacquinia keyensis and Penicillium neoherquei from a minute mushroom sporocarp. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Boers J, Holdom D, et al. 2022. Fungal Planet description sheets: 1383-1435. Persoonia 48: 261-371. https://doi.org/10.3767/persoonia.2022.48.08.

3.
Mycologia ; 113(4): 828-841, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34110972

RESUMO

A phylogenetic analysis of nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS), nuc rDNA 28S domains D1-D2 (28S), and the region between conserved domains 6 and 7 of RNA polymerase II second largest subunit (RPB2) from multiple species of Alpova and Melanogaster revealed four major clades, proposed here as distinct genera: Melanogaster, Alpova s. str. containing the type species A. cinnamomeus, Neoalpova for the species around N. rubescens, and the new genus Paralpova, proposed here for P. artikutzensis, sp. nov. Alpova, Neoalpova, and Paralpova form a monophyletic lineage of hypogeous fungi with a pseudoparenchymatic structure in their peridium (at least in the inner layer) that could be interpreted as a single genus, but they are separated due to distinct morphological and ecological traits. Alpova s. str. is employed for species strictly associated with Alnus, lacking a conspicuous odor, and producing relatively small basidiomata and basidiospores <10 µm long. Neoalpova and Paralpova occur under other hosts, present a conspicuous odor, have larger basidiomata and basidiospores than Alpova, and have a prosenchymatic peridiopellis. Finally, Paralpova is characterized by the yellowish gleba, monosporic or bisporic basidia, and basidiospores >15 µm long with a mean length/width ratio (Qm) of <2.0. In addition, two new species of Neoalpova are proposed: N. arenicola, associated with Mediterranean forests in sandy soils and with spores slightly smaller and wider than those of N. rubescens, and N. montecchii, a cryptic species very similar to N. rubescens but for its putatively smaller peridiopellis elements and its genetic profile.


Assuntos
Basidiomycota , Basidiomycota/genética , DNA Fúngico/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Filogenia , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Esporos Fúngicos
4.
Persoonia ; 47: 178-374, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37693795

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii from a grassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis on calcareous soil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica), Inocybe corsica on wet ground. France (French Guiana), Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany, Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India, Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran, Pythium serotinoosporum from soil under Prunus dulcis. Italy, Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan, Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan, Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia, Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Euphorbia sp. Netherlands, Alfaria junci, Myrmecridium junci, Myrmecridium juncicola, Myrmecridium juncigenum, Ophioceras junci, Paradinemasporium junci (incl. Paradinemasporium gen. nov.), Phialoseptomonium junci, Sporidesmiella juncicola, Xenopyricularia junci and Zaanenomyces quadripartis (incl. Zaanenomyces gen. nov.), from dead culms of Juncus effusus, Cylindromonium everniae and Rhodoveronaea everniae from Evernia prunastri, Cyphellophora sambuci and Myrmecridium sambuci from Sambucus nigra, Kiflimonium junci, Sarocladium junci, Zaanenomyces moderatricis-academiae and Zaanenomyces versatilis from dead culms of Juncus inflexus, Microcera physciae from Physcia tenella, Myrmecridium dactylidis from dead culms of Dactylis glomerata, Neochalara spiraeae and Sporidesmium spiraeae from leaves of Spiraea japonica, Neofabraea salicina from Salix sp., Paradissoconium narthecii (incl. Paradissoconium gen. nov.) from dead leaves of Narthecium ossifragum, Polyscytalum vaccinii from Vaccinium myrtillus, Pseudosoloacrosporiella cryptomeriae (incl. Pseudosoloacrosporiella gen. nov.) from leaves of Cryptomeria japonica, Ramularia pararhabdospora from Plantago lanceolata, Sporidesmiella pini from needles of Pinus sylvestris and Xenoacrodontium juglandis (incl. Xenoacrodontium gen. nov. and Xenoacrodontiaceae fam. nov.) from Juglans regia. New Zealand, Cryptometrion metrosideri from twigs of Metrosideros sp., Coccomyces pycnophyllocladi from dead leaves of Phyllocladus alpinus, Hypoderma aliforme from fallen leaves Fuscopora solandri and Hypoderma subiculatum from dead leaves Phormium tenax. Norway, Neodevriesia kalakoutskii from permafrost and Variabilispora viridis from driftwood of Picea abies. Portugal, Entomortierella hereditatis from a biofilm covering a deteriorated limestone wall. Russia, Colpoma junipericola from needles of Juniperus sabina, Entoloma cinnamomeum on soil in grasslands, Entoloma verae on soil in grasslands, Hyphodermella pallidostraminea on a dry dead branch of Actinidia sp., Lepiota sayanensis on litter in a mixed forest, Papiliotrema horticola from Malus communis, Paramacroventuria ribis (incl. Paramacroventuria gen. nov.) from leaves of Ribes aureum and Paramyrothecium lathyri from leaves of Lathyrus tuberosus. South Africa, Harzia combreti from leaf litter of Combretum collinum ssp. sulvense, Penicillium xyleborini from Xyleborinus saxesenii, Phaeoisaria dalbergiae from bark of Dalbergia armata, Protocreopsis euphorbiae from leaf litter of Euphorbia ingens and Roigiella syzygii from twigs of Syzygium chordatum. Spain, Genea zamorana on sandy soil, Gymnopus nigrescens on Scleropodium touretii, Hesperomyces parexochomi on Parexochomus quadriplagiatus, Paraphoma variabilis from dung, Phaeococcomyces kinklidomatophilus from a blackened metal railing of an industrial warehouse and Tuber suaveolens in soil under Quercus faginea. Svalbard and Jan Mayen, Inocybe nivea associated with Salix polaris. Thailand, Biscogniauxia whalleyi on corticated wood. UK, Parasitella quercicola from Quercus robur. USA, Aspergillus arizonicus from indoor air in a hospital, Caeliomyces tampanus (incl. Caeliomyces gen. nov.) from office dust, Cippumomyces mortalis (incl. Cippumomyces gen. nov.) from a tombstone, Cylindrium desperesense from air in a store, Tetracoccosporium pseudoaerium from air sample in house, Toxicocladosporium glendoranum from air in a brick room, Toxicocladosporium losalamitosense from air in a classroom, Valsonectria portsmouthensis from air in men's locker room and Varicosporellopsis americana from sludge in a water reservoir. Vietnam, Entoloma kovalenkoi on rotten wood, Fusarium chuoi inside seed of Musa itinerans, Micropsalliota albofelina on soil in tropical evergreen mixed forests and Phytophthora docyniae from soil and roots of Docynia indica. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Jurjevic Z, et al. 2021. Fungal Planet description sheets: 1284-1382. Persoonia 47: 178-374. https://doi.org/10.3767/persoonia.2021.47.06.

5.
Persoonia ; 47: 178-374, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38352974

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii from a grassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis on calcareous soil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica), Inocybe corsica on wet ground. France (French Guiana), Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany, Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India, Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran, Pythium serotinoosporum from soil under Prunus dulcis. Italy, Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan, Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan, Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia, Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Euphorbia sp. Netherlands, Alfaria junci, Myrmecridium junci, Myrmecridium juncicola, Myrmecridium juncigenum, Ophioceras junci, Paradinemasporium junci (incl. Paradinemasporium gen. nov.), Phialoseptomonium junci, Sporidesmiella juncicola, Xenopyricularia junci and Zaanenomyces quadripartis (incl. Zaanenomyces gen. nov.), from dead culms of Juncus effusus, Cylindromonium everniae and Rhodoveronaea everniae from Evernia prunastri, Cyphellophora sambuci and Myrmecridium sambuci from Sambucus nigra, Kiflimonium junci, Sarocladium junci, Zaanenomyces moderatricis-academiae and Zaanenomyces versatilis from dead culms of Juncus inflexus, Microcera physciae from Physcia tenella, Myrmecridium dactylidis from dead culms of Dactylis glomerata, Neochalara spiraeae and Sporidesmium spiraeae from leaves of Spiraea japonica, Neofabraea salicina from Salix sp., Paradissoconium narthecii (incl. Paradissoconium gen. nov.) from dead leaves of Narthecium ossifragum, Polyscytalum vaccinii from Vaccinium myrtillus, Pseudosoloacrosporiella cryptomeriae (incl. Pseudosoloacrosporiella gen. nov.) from leaves of Cryptomeria japonica, Ramularia pararhabdospora from Plantago lanceolata, Sporidesmiella pini from needles of Pinus sylvestris and Xenoacrodontium juglandis (incl. Xenoacrodontium gen. nov. and Xenoacrodontiaceae fam. nov.) from Juglans regia. New Zealand, Cryptometrion metrosideri from twigs of Metrosideros sp., Coccomyces pycnophyllocladi from dead leaves of Phyllocladus alpinus, Hypoderma aliforme from fallen leaves Fuscopora solandri and Hypoderma subiculatum from dead leaves Phormium tenax. Norway, Neodevriesia kalakoutskii from permafrost and Variabilispora viridis from driftwood of Picea abies. Portugal, Entomortierella hereditatis from a biofilm covering a deteriorated limestone wall. Russia, Colpoma junipericola from needles of Juniperus sabina, Entoloma cinnamomeum on soil in grasslands, Entoloma verae on soil in grasslands, Hyphodermella pallidostraminea on a dry dead branch of Actinidia sp., Lepiota sayanensis on litter in a mixed forest, Papiliotrema horticola from Malus communis, Paramacroventuria ribis (incl. Paramacroventuria gen. nov.) from leaves of Ribes aureum and Paramyrothecium lathyri from leaves of Lathyrus tuberosus. South Africa, Harzia combreti from leaf litter of Combretum collinum ssp. sulvense, Penicillium xyleborini from Xyleborinus saxesenii, Phaeoisaria dalbergiae from bark of Dalbergia armata, Protocreopsis euphorbiae from leaf litter of Euphorbia ingens and Roigiella syzygii from twigs of Syzygium chordatum. Spain, Genea zamorana on sandy soil, Gymnopus nigrescens on Scleropodium touretii, Hesperomyces parexochomi on Parexochomus quadriplagiatus, Paraphoma variabilis from dung, Phaeococcomyces kinklidomatophilus from a blackened metal railing of an industrial warehouse and Tuber suaveolens in soil under Quercus faginea. Svalbard and Jan Mayen, Inocybe nivea associated with Salix polaris. Thailand, Biscogniauxia whalleyi on corticated wood. UK, Parasitella quercicola from Quercus robur. USA, Aspergillus arizonicus from indoor air in a hospital, Caeliomyces tampanus (incl. Caeliomyces gen. nov.) from office dust, Cippumomyces mortalis (incl. Cippumomyces gen. nov.) from a tombstone, Cylindrium desperesense from air in a store, Tetracoccosporium pseudoaerium from air sample in house, Toxicocladosporium glendoranum from air in a brick room, Toxicocladosporium losalamitosense from air in a classroom, Valsonectria portsmouthensis from air in men's locker room and Varicosporellopsis americana from sludge in a water reservoir. Vietnam, Entoloma kovalenkoi on rotten wood, Fusarium chuoi inside seed of Musa itinerans, Micropsalliota albofelina on soil in tropical evergreen mixed forests and Phytophthora docyniae from soil and roots of Docynia indica. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Jurjevic Z, et al. 2021. Fungal Planet description sheets: 1284-1382. Persoonia 47: 178-374. https://doi.org/10.3767/persoonia.2021.47.06.

6.
Persoonia ; 42: 127-185, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31551617

RESUMO

A comprehensive morphological and genetic study of type material and new collections of sequestrate Russulales species formerly belonging to the genera Arcangeliella, Elasmomyces, Gymnomyces, Hydnangium, Hymenogaster, Macowanites, Martellia, Secotium and Zelleromyces is here undertaken, for the purpose of providing a complete taxonomical revision of sequestrate Russulaceae species in the Mediterranean and temperate regions of Europe. As a result, seven distinct taxa in the genus Lactarius and 18 in the genus Russula are identified. Six of them are new species: L. populicola, L. subgiennensis, R. bavarica, R. candidissima, R. hobartiae and R. mediterraneensis, and seven represent new combinations: L. josserandii (≡ Zelleromyces josserandii), L. soehneri (≡ Hydnangium soehneri), R. candida (≡ Hydnangium candidum), R. cerea (≡ Hydnangium cereum), R. messapica var. messapicoides (≡ Macowanites messapicoides), R. meridionalis (≡ Zelleromyces meridionalis) and R. neuhoffii (≡ Hydnangium neuhoffii). Twenty-two of the 25 taxa are illustrated, while descriptions, microscopy images, as well as extensive information on the ecology, chorology and phylogeny for all taxa are provided. A key is further included to facilitate their identification.

7.
Persoonia ; 43: 223-425, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32214501

RESUMO

Novel species of fungi described in this study include those from various countries as follows: Antarctica, Apenidiella antarctica from permafrost, Cladosporium fildesense from an unidentified marine sponge. Argentina, Geastrum wrightii on humus in mixed forest. Australia, Golovinomyces glandulariae on Glandularia aristigera, Neoanungitea eucalyptorum on leaves of Eucalyptus grandis, Teratosphaeria corymbiicola on leaves of Corymbia ficifolia, Xylaria eucalypti on leaves of Eucalyptus radiata. Brazil, Bovista psammophila on soil, Fusarium awaxy on rotten stalks of Zea mays, Geastrum lanuginosum on leaf litter covered soil, Hermetothecium mikaniae-micranthae (incl. Hermetothecium gen. nov.) on Mikania micrantha, Penicillium reconvexovelosoi in soil, Stagonosporopsis vannaccii from pod of Glycine max. British Virgin Isles, Lactifluus guanensis on soil. Canada, Sorocybe oblongispora on resin of Picea rubens. Chile, Colletotrichum roseum on leaves of Lapageria rosea. China, Setophoma caverna from carbonatite in Karst cave. Colombia, Lareunionomyces eucalypticola on leaves of Eucalyptus grandis. Costa Rica, Psathyrella pivae on wood. Cyprus, Clavulina iris on calcareous substrate. France, Chromosera ambigua and Clavulina iris var. occidentalis on soil. French West Indies, Helminthosphaeria hispidissima on dead wood. Guatemala, Talaromyces guatemalensis in soil. Malaysia, Neotracylla pini (incl. Tracyllales ord. nov. and Neotracylla gen. nov.) and Vermiculariopsiella pini on needles of Pinus tecunumanii. New Zealand, Neoconiothyrium viticola on stems of Vitis vinifera, Parafenestella pittospori on Pittosporum tenuifolium, Pilidium novae-zelandiae on Phoenix sp. Pakistan, Russula quercus-floribundae on forest floor. Portugal, Trichoderma aestuarinum from saline water. Russia, Pluteus liliputianus on fallen branch of deciduous tree, Pluteus spurius on decaying deciduous wood or soil. South Africa, Alloconiothyrium encephalarti, Phyllosticta encephalarticola and Neothyrostroma encephalarti (incl. Neothyrostroma gen. nov.) on leaves of Encephalartos sp., Chalara eucalypticola on leaf spots of Eucalyptus grandis × urophylla, Clypeosphaeria oleae on leaves of Olea capensis, Cylindrocladiella postalofficium on leaf litter of Sideroxylon inerme, Cylindromonium eugeniicola (incl. Cylindromonium gen. nov.) on leaf litter of Eugenia capensis, Cyphellophora goniomatis on leaves of Gonioma kamassi, Nothodactylaria nephrolepidis (incl. Nothodactylaria gen. nov. and Nothodactylariaceae fam. nov.) on leaves of Nephrolepis exaltata, Falcocladium eucalypti and Gyrothrix eucalypti on leaves of Eucalyptus sp., Gyrothrix oleae on leaves of Olea capensis subsp. macrocarpa, Harzia metrosideri on leaf litter of Metrosideros sp., Hippopotamyces phragmitis (incl. Hippopotamyces gen. nov.) on leaves of Phragmites australis, Lectera philenopterae on Philenoptera violacea, Leptosillia mayteni on leaves of Maytenus heterophylla, Lithohypha aloicola and Neoplatysporoides aloes on leaves of Aloe sp., Millesimomyces rhoicissi (incl. Millesimomyces gen. nov.) on leaves of Rhoicissus digitata, Neodevriesia strelitziicola on leaf litter of Strelitzia nicolai, Neokirramyces syzygii (incl. Neokirramyces gen. nov.) on leaf spots of Syzygium sp., Nothoramichloridium perseae (incl. Nothoramichloridium gen. nov. and Anungitiomycetaceae fam. nov.) on leaves of Persea americana, Paramycosphaerella watsoniae on leaf spots of Watsonia sp., Penicillium cuddlyae from dog food, Podocarpomyces knysnanus (incl. Podocarpomyces gen. nov.) on leaves of Podocarpus falcatus, Pseudocercospora heteropyxidicola on leaf spots of Heteropyxis natalensis, Pseudopenidiella podocarpi, Scolecobasidium podocarpi and Ceramothyrium podocarpicola on leaves of Podocarpus latifolius, Scolecobasidium blechni on leaves of Blechnum capense, Stomiopeltis syzygii on leaves of Syzygium chordatum, Strelitziomyces knysnanus (incl. Strelitziomyces gen. nov.) on leaves of Strelitzia alba, Talaromyces clemensii from rotting wood in goldmine, Verrucocladosporium visseri on Carpobrotus edulis. Spain, Boletopsis mediterraneensis on soil, Calycina cortegadensisi on a living twig of Castanea sativa, Emmonsiellopsis tuberculata in fluvial sediments, Mollisia cortegadensis on dead attached twig of Quercus robur, Psathyrella ovispora on soil, Pseudobeltrania lauri on leaf litter of Laurus azorica, Terfezia dunensis in soil, Tuber lucentum in soil, Venturia submersa on submerged plant debris. Thailand, Cordyceps jakajanicola on cicada nymph, Cordyceps kuiburiensis on spider, Distoseptispora caricis on leaves of Carex sp., Ophiocordyceps khonkaenensis on cicada nymph. USA, Cytosporella juncicola and Davidiellomyces juncicola on culms of Juncus effusus, Monochaetia massachusettsianum from air sample, Neohelicomyces melaleucae and Periconia neobrittanica on leaves of Melaleuca styphelioides × lanceolata, Pseudocamarosporium eucalypti on leaves of Eucalyptus sp., Pseudogymnoascus lindneri from sediment in a mine, Pseudogymnoascus turneri from sediment in a railroad tunnel, Pulchroboletus sclerotiorum on soil, Zygosporium pseudomasonii on leaf of Serenoa repens. Vietnam, Boletus candidissimus and Veloporphyrellus vulpinus on soil. Morphological and culture characteristics are supported by DNA barcodes.

8.
An. med. interna (Madr., 1983) ; 23(12): 585-587, dic. 2006. ilus
Artigo em Es | IBECS | ID: ibc-051773

RESUMO

El cáncer de páncreas es una neoplasia agresiva, con mal pronóstico y poca supervivencia. La mayoría de los pacientes se diagnostican en fases avanzadas, por lo que sólo se puede realizar tratamiento paliativo. La pancreatitis crónica predispone al desarrollo de cáncer de páncreas, considerándose que la inflamación juega un papel importante en el desarrollo temprano de la malignidad, estableciéndose un nexo de unión entre ambas patologías. El diagnóstico diferencial entre la pancreatitis crónica y el cáncer de páncreas en las fases iniciales es difícil de realizar por la escasa sensibilidad y especificidad de las pruebas diagnósticas de imagen y de los marcadores tumorales. Presentamos un caso clínico sugestivo de cáncer de páncreas, cuyo diagnóstico se realizó dos años después del tratamiento paliativo


Pancreatic cancer is an aggressive neoplasm, with poor prognosis and survival. As most patients with pancreatic cancer are diagnosed at an advanced stage, the objetive of mostly treatment is palliative. Predisposing medical conditions for the development of pancreatic cancer include chronic pancreatitis. The link between the two pathologies is supported in that pancreatic inflammation may play a role in the early development of pancreatic malignancy. The difficulties in discriminating between chronic pancreatitis and adenocarcinoma in the early state, using currently employed diagnosis imaging and tumour marker analysis, result in poor sensitivity and specificity in the diagnosis. We report one case suggestive of pancreatic cancer that was diagnosed two years after palliative treatment


Assuntos
Masculino , Pessoa de Meia-Idade , Humanos , Cuidados Paliativos/métodos , Cuidados Paliativos/tendências , Sensibilidade e Especificidade , Colestase/complicações , Colonoscopia/métodos , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Neoplasias Pancreáticas/diagnóstico , Diagnóstico Diferencial , Pancreatite/complicações , Pancreatite/diagnóstico , Pâncreas/patologia , Pâncreas/cirurgia
9.
An Med Interna ; 23(12): 585-7, 2006 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-17371147

RESUMO

Pancreatic cancer is an aggressive neoplasm, with poor prognosis and survival. As most patients with pancreatic cancer are diagnosed at an advanced stage, the objective of mostly treatment is palliative. Predisposing medical conditions for the development of pancreatic cancer include chronic pancreatitis. The link between the two pathologies is supported in that pancreatic inflammation may play a role in the early development of pancreatic malignancy. The difficulties in discriminating between chronic pancreatitis and adenocarcinoma in the early state, using currently employed diagnosis imaging and tumour marker analysis, result in poor sensitivity and specificity in the diagnosis. We report one case suggestive of pancreatic cancer that was diagnosed two years after palliative treatment.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Cuidados Paliativos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/terapia , Idoso , Evolução Fatal , Humanos , Masculino , Pancreatite Crônica/diagnóstico , Fatores de Tempo
10.
Scand J Gastroenterol ; 37(9): 1017-24, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12374225

RESUMO

BACKGROUND: Gastrin exerts trophic effects on the gastric mucosa by mechanisms not yet completely elucidated. Our aim was to localize the cholecystokinin-2 (CCK2) receptor in epithelial cells of foetal and adult rat stomachs in order to determine the cell types that are directly affected by gastrin. METHODS: Gastric tissue was subjected to indirect double immunofluorescence staining with antiserum against the C-terminal decapeptide of the CCK2 receptor and antibodies against 5' bromo-2-deoxyuridine, which had been injected into the rats I h before they were killed, the acid pump H,K-ATPase, the membrane-cytoskeletal linker ezrin, pepsin/pepsinogen or histidine decarboxylase. RESULTS: Undifferentiated foetal gastric epithelial cells expressed CCK2 receptors, whereas stem cells of adult gastric glands did not exhibit immunoreactivity. However, other epithelial cells in the progenitor zone of adult gastric glands did express CCK2 receptors. Some of these cells were faintly stained for H,K-ATPase; pepsin/pepsinogen was also detected in this region. Parietal cells in the isthmus/pit region of the glands contained ezrin, and some showed weak immunoreactivity for the CCK2 receptor. As expected, enterochromaffin-like cells also expressed CCK2 receptors. CONCLUSION: Our findings are consistent with the hypothesis that a CCK2 receptor mediates direct effects of gastrin on gastric epithelial cells during both stomach organogenesis and adult life.


Assuntos
Mucosa Gástrica/metabolismo , Receptores da Colecistocinina/metabolismo , Animais , Feminino , Imunofluorescência , Mucosa Gástrica/embriologia , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Receptor de Colecistocinina B
11.
Scand J Gastroenterol ; 36(9): 904-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11521978

RESUMO

BACKGROUND: Our understanding of the pathophysiology of gastro-oesophageal reflux disease (GERD) in man is limited. The aim of the present study was to establish a long-term (>1 year) animal model for reflux oesophagitis which would allow us to study various aspects of the development of chronic reflux oesophagitis. METHODS: Myotomy was carried out in the gastro-oesophageal junction in eight cats; seven other cats were sham-operated. Before the operation, and every 2 months thereafter, oesophagoscopy was carried out, biopsies were taken for histology, and manometry was performed to determine the lower oesophageal sphincter pressure (LESP). The cats were killed 1 year after the operation. RESULTS: The myotomy operation resulted in a significantly decreased LESP. In oesophageal biopsies from these cats, there was a varying degree of oesophagitis starting already 2 months after surgery. In six of the eight myotomized cats there was hyperplasia of the stratum basale, and cardiac type metaplasia was observed in two cats. The control cats showed no significant changes in LESP or in the histology of the oesophagus. CONCLUSIONS: In cats followed for more than a year, myotomy in the gastro-oesophageal junction results in reflux oesophagitis similar to that seen in patients with chronic gastro-oesophageal reflux.


Assuntos
Esofagite Péptica , Esôfago/patologia , Animais , Gatos , Modelos Animais de Doenças , Esofagite Péptica/etiologia , Esofagite Péptica/patologia , Esofagite Péptica/fisiopatologia , Junção Esofagogástrica/fisiologia , Esôfago/cirurgia , Mucosa/patologia , Pressão , Fatores de Tempo
12.
Anat Embryol (Berl) ; 201(3): 149-56, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10664176

RESUMO

At gestational day 16 the epithelium of the rat stomach consists of a stratified layer of undifferentiated cells, and two days later glandular structures appear. The present study was carried out to identify extracellular matrix proteins that could be involved in the epithelial cell proliferation and differentiation processes that occur in the fetal rat stomach during this period. For comparative purposes the expression of the same components in the adult gastric mucosa was examined. Pregnant Sprague-Dawley rats received an intraperitoneal injection of 5-bromo-2'-deoxyuridine to label proliferating cells. One, 3.5, or 6 h post-injection the stomachs were excised and immediately frozen. The specimens were sectioned and stained with hematoxylin and eosin or for 5-bromo-2'-deoxyuridine, cytokeratin no. 8, H,K-ATPase, and the extracellular matrix proteins fibronectin, laminin, and collagens type I and IV. A stratified layer of proliferating cells was observed in the epithelium of the fetal stomachs, while in adult stomachs proliferating cells were detected in the isthmus/neck region of the glands. Cytokeratin, an epithelial cell marker, was sparse at gestational day 16 but abundant both at gestational day 18 and in the isthmus/neck region of gastric glands of the adult stomach. The parietal cell marker H,K-ATPase could not be detected in the fetal stomachs during this period. Fibronectin was observed in the stroma of both fetal and adult stomachs. Collagen type I could only be detected in the stroma close to the oesophagus at gestational day 16. Two days later, collagen type I was abundant in the lamina propria, the submucosa and in the serosa of the fetal stomachs. In adult tissue collagen type I was detected in the surface epithelium, the submucosa and in the serosa of the stomach. Collagen type IV and laminin were expressed in the lamina propria, the basement membranes around blood vessels, muscle cells, and nerve bundles, as well as in the serosa of both 16- and 18-day-old fetal and adult rat stomachs. In conclusion, a high cell proliferation rate was observed in the epithelium at both gestational days 16 and 18. The increased expression of cytokeratin observed during this period indicates that the epithelial character of the embryonic cells becomes more distinct, while the remarkable change in the expression of collagen type I might reflect an important role of collagen type I in the development of the gastric epithelium.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Mucosa Gástrica/embriologia , Animais , Diferenciação Celular , Colágeno/metabolismo , Desenvolvimento Embrionário e Fetal , Células Epiteliais/citologia , Fibronectinas/metabolismo , Mucosa Gástrica/citologia , Mucosa Gástrica/metabolismo , Imuno-Histoquímica , Queratinas/metabolismo , Laminina/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
Biochim Biophys Acta ; 1451(2-3): 297-304, 1999 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-10556584

RESUMO

The enterochromaffin-like (ECL) cells play an important role in the regulation of gastric acid secretion. They respond to gastrin by a prompt increase in histamine secretion, an effect which is mediated by the CCK-(B)/gastrin receptor acting through the IP(3)/DAG pathway. In the rat, long-term treatment with acid secretion inhibitors induces hypergastrinaemia which, in turn, results in ECL cell hypertrophy and hyperplasia. The aim of the present study was to evaluate various functional parameters in acutely isolated rat ECL cells, following long-term hypergastrinaemia in vivo. Rats were treated with vehicle or a supramaximal daily dose of omeprazole for more than 10 weeks to ensure ECL cell hyperplasia. ECL cells were isolated from vehicle-treated animals and 24, 72 and 120 h after the last dose of omeprazole. The functional activity of the acutely isolated ECL cells was determined by measuring gastrin-and forskolin-induced histamine secretion. Changes in cytosolic free calcium upon gastrin stimulation were monitored by digital video imaging. ECL cells successively regained their ability to respond to gastrin following long-term hypergastrinaemia, reaching close to vehicle-treated levels 120 h after the last dose of omeprazole. In the rat, the response pattern of the ECL cells appears to normalise in parallel with the normalisation of plasma gastrin levels.


Assuntos
Celulas Tipo Enterocromafim/efeitos dos fármacos , Gastrinas/farmacologia , Animais , Antiulcerosos/farmacologia , Cálcio/análise , Cálcio/metabolismo , Contagem de Células , Citosol/efeitos dos fármacos , Citosol/metabolismo , Feminino , Gastrinas/sangue , Histamina/análise , Liberação de Histamina/efeitos dos fármacos , Omeprazol/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
14.
Acta Physiol Scand ; 159(2): 155-61, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9055943

RESUMO

The current understanding of the mechanisms controlling the proliferation and differentiation of the stem cells of the gastric oxyntic glands is limited. The aim of the present study was to develop a method for investigating proliferation and differentiation of undifferentiated cells from fetal rat stomach. Outgrowth of cells was initiated from explants of 16-day-old fetal rat stomachs. At this stage of the fetal development the gastric epithelial cells are undifferentiated. The explants were cultured in DMEM/F-12 medium supplemented with fetal calf serum only, or fetal calf serum combined with either hydrocortisone or pentagastrin. Morphological characterization by means of light microscopy, dye staining and immunostaining was used to identify the growing cells. Both hydrocortisone and pentagastrin accelerated the differentiation towards H,K-ATPase-positive cells, mucus-producing cells and other epithelial cells. H,K-ATPase-positive cells, which were identified by immunostaining with a monoclonal antibody reacting with the alpha-subunit of the H,K-ATPase, grew on top of the confluent layer of epithelioid and fibroblastoid cells. With this method in vitro investigations of the mechanisms of proliferation and differentiation of gastric mucosal cells are possible. Although by different mechanisms, both hydrocortisone and pentagastrin appear to play a regulatory role in these processes.


Assuntos
Feto/citologia , Mucosa Gástrica/embriologia , Animais , Anticorpos Monoclonais , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Técnicas de Cultura , Ensaio de Imunoadsorção Enzimática , Feto/metabolismo , Mucosa Gástrica/citologia , Mucosa Gástrica/efeitos dos fármacos , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Hidrocortisona/farmacologia , Células Parietais Gástricas/citologia , Pentagastrina/farmacologia , Ratos , Ratos Sprague-Dawley , Suínos
15.
Scand J Gastroenterol ; 31(1): 24-30, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8927936

RESUMO

BACKGROUND: Histamine is thought to play a central role in the regulation of gastric acid secretion. In the rat oxyntic mucosa most of the histamine is synthesized and stored in enterochromaffin-like (ECL) cells, and the rest resides in mast cells. The present study examines the role of ECL-cell histamine in the control of acid secretion in the intact, conscious rat. METHODS: Rats were treated with alpha-fluoromethylhistidine (alpha-FMH) to inhibit histamine synthesis. alpha-FMH was given by continuous subcutaneous infusion (3 mg/kg/h) for up to 9 days. An additional oral dose of alpha-FMH (50 mg/kg) was given 2 h before each acid secretion test. Acid secretion was studied in pylorus-ligated rats and in chronic gastric fistula rats stimulated with histamine, gastrin-17, or insulin after 2-6 days of alpha-FMH infusion. RESULTS: Treatment with alpha-FMH lowered oxyntic mucosal histamine synthesis by 80%. From previous observations this is thought to reflect depletion of histamine from the ECL cells. The remaining 20% resides in mucosal and submucosal mast cells, which seem to be resistant to alpha-FMH. Basal acid secretion was inhibited by more than 60% after alpha-FMH treatment and by more than 80% by ranitidine. Histamine-stimulated secretion was unaffected by alpha-FMH and abolished by the histamine H2-receptor antagonist ranitidine. The acid response to gastrin-17 was almost abolished in histamine-depleted rats and abolished by ranitidine. Vagally induced acid secretion (provoked by the injection of insulin or by pylorus ligation) was unaffected by alpha-FMH treatment but abolished by ranitidine and by the muscarinic M1-receptor antagonist pirenzepine. CONCLUSION: The results suggest that gastrin stimulates acid secretion by releasing histamine from ECL cells. Vagally induced acid secretion is also dependent on a histaminergic pathway but not on ECL-cell histamine.


Assuntos
Células Enterocromafins/metabolismo , Ácido Gástrico/metabolismo , Histamina/fisiologia , Células Parietais Gástricas/efeitos dos fármacos , Células Parietais Gástricas/fisiologia , Animais , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Feminino , Fístula Gástrica/fisiopatologia , Gastrinas/fisiologia , Metilistidinas/farmacologia , Ratos , Ratos Sprague-Dawley
16.
Am J Physiol ; 268(1 Pt 1): G82-9, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7840210

RESUMO

The role of endogenous adenosine 3',5'-cyclic monophosphate (cAMP) in the mechanisms of action of gastrin and carbachol on aminopyrine accumulation in isolated pig and rat parietal cells was investigated. In pig cells, pentagastrin (100 nM) alone stimulated aminopyrine accumulation, an action significantly reduced by the protein kinase A inhibitor Rp-adenosine 3',5'-cyclic monophosphothioate (Rp-cAMP[S]; 100 microM). In rat cells, gastrin-17 (100 nM) was incapable of stimulating aminopyrine accumulation, but it potentiated the action of histamine (100 microM). Carbachol (10 microM) stimulated aminopyrine accumulation and potentiated the action of histamine, and its action was potentiated in a dose-dependent manner by Sp-adenosine 3',5'-cyclic monophosphothioate (Sp-cAMP[S]; a cAMP analogue) in both species. The effect of carbachol was dose dependently reduced by Rp-cAMP[S]. The basal cAMP in pig parietal cells was 3.5-fold higher than that in rat parietal cells. Histamine (100 microM) and 3-isobutyl-1-methylxanthine (IBMX; 100 microM) only slightly elevated the cAMP content (1.2- to 2.9-fold the basal level) in both pig and rat parietal cells. Their combination, however, increased the cAMP level by 8- to 38-fold, but it did not increase aminopyrine accumulation above that elicited by histamine alone. Gastrin did not alter the cAMP levels in parietal cells of either of the two species. Both gastrin and carbachol increased cytosolic free Ca2+ in enriched pig and rat parietal cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aminopirina/metabolismo , Carbacol/farmacologia , AMP Cíclico/fisiologia , Gastrinas/farmacologia , Células Parietais Gástricas/metabolismo , Animais , Separação Celular , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Histamina/farmacologia , Técnicas In Vitro , Inibidores de Proteínas Quinases , Ratos , Suínos , Tionucleotídeos/farmacologia
17.
Biochim Biophys Acta ; 1177(3): 245-52, 1993 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-7686773

RESUMO

The mechanism of action of gastrin on pig parietal cells was investigated. The aminopyrine accumulation technique was used to estimate acid production in gastric mucosal cells, containing 10-20% parietal cells, and in enriched parietal cells, containing 65-95% parietal cells. The gastrin analogue pentagastrin stimulated aminopyrine accumulation in a dose-dependent fashion irrespective of the proportion of non-parietal cells present. The apparent EC50 for pentagastrin was 5 nM and the maximally effective concentration was 100 nM. The histamine H2-receptor antagonist ranitidine did not affect the action of pentagastrin. The stimulatory effects of various doses of histamine on aminopyrine accumulation in highly enriched parietal cells were potentiated by the inclusion of 100 nM pentagastrin in the incubation medium. In another series of experiments using mucosal cells, the action of effective doses of pentagastrin were potentiated by the phosphodiesterase inhibitor isobutylmethyl xanthine (IBMX), which alone elicited an aminopyrine accumulation equal to 50% of that obtained by 100 microM histamine. When ranitidine (100 microM) was included, the action of IBMX was almost completely abolished. However, the dose-response curve for pentagastrin in the presence of ranitidine plus IBMX was similar to that obtained in the absence of IBMX. Dibutyryl-cAMP (DBcAMP, 1 mM) in the presence of ranitidine (100 microM) also potentiated the action of all effective doses of pentagastrin on mucosal cells. The protein kinase A inhibitor Rp-cAMPS, present at 500 microM in the incubation medium, significantly reduced the action of each effective concentration of pentagastrin on aminopyrine accumulation in enriched parietal cells. These results in pig parietal cells were interpreted as indicative of: (i) an action of gastrin exerted directly on the parietal cells; (ii) elevation of intracellular cAMP having a permissive role in the action of gastrin on aminopyrine accumulation.


Assuntos
Aminopirina/metabolismo , Gastrinas/metabolismo , Células Parietais Gástricas/metabolismo , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Bucladesina/farmacologia , Relação Dose-Resposta a Droga , Histamina/farmacologia , Técnicas In Vitro , Pentagastrina/farmacologia , Inibidores de Proteínas Quinases , Suínos
18.
Biochim Biophys Acta ; 1175(3): 250-6, 1993 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-8435440

RESUMO

In isolated rat parietal cells, a potentiating effect by gastrin of the stimulatory action of histamine and dibutyryl-cAMP (DBcAMP) on aminopyrine accumulation, an index of the acid formed and trapped by the cells, was recently reported by us (1991, Am. J. Physiol. 261, G621-G627). In the present study, this mechanism of action of gastrin was further investigated. Enriched parietal cells (approximately 65% parietal cells) were incubated under different conditions and processed for electron microscopy. Morphometric analysis of the micrographs revealed that pentagastrin (100 nM) was as efficient as histamine (100 microM) in inducing the formation of vacuolar/canalicular spaces in the parietal cells. In the presence of the histamine H2-receptor antagonist ranitidine, histamine was ineffective but pentagastrin and gastrin-17 (G17) maintained their capacity to induce the morphological transformations. By stimulation with pentagastrin plus histamine, the vacuolar/canalicular volume was 2-fold higher than by stimulation separately with each one of the secretagogues. G-17 (100 nM) alone was ineffective but potentiated the maximal [14C]aminopyrine accumulation obtained with 100 microM histamine in mucosal cells (approximately 25-35% parietal cells). Ranitidine blocked both histamine-and histamine plus G-17-stimulated aminopyrine accumulation. G-17 potentiated also the stimulation by 1 mM dibutyryl-cyclic AMP but this was not inhibited by ranitidine. Pentagastrin (100 nM) increased the basal [14C]glucose oxidation in mucosal cells by 30%. This increase was not blocked by ranitidine which, however, abolished the histamine-stimulated glucose oxidation. Incubation of the cells with pentagastrin plus histamine resulted in a glucose oxidation which equaled the sum of the values obtained by each one of the agents. These results indicate that gastrin, acting directly on the parietal cells, potentiates the action of histamine on aminopyrine accumulation by increasing the vacuolar/canalicular spaces, a process that is reflected in the metabolic activity of the cells. Thus a major effect of gastrin at the parietal cell level appears to be the induction of a morphology which is characteristic of stimulated cells rather than a direct activation of ion-transport mechanisms.


Assuntos
Gastrinas/farmacologia , Células Parietais Gástricas/efeitos dos fármacos , Aminopirina/metabolismo , Animais , Glucose/metabolismo , Histamina/farmacologia , Masculino , Células Parietais Gástricas/ultraestrutura , Ranitidina/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
19.
Biochem Biophys Res Commun ; 183(3): 1097-102, 1992 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-1567389

RESUMO

The effects of gastrin on cytosolic free Ca2+ ([Ca2+]i) in single, isolated rat gastric parietal cells were investigated using the fluorescent probe Fura-2 and digital image analysis. [Ca2+]i was increased by gastrin (100 nM) in approximately 30% of the parietal cells, which were identified by using either the fluorescent probe acridine orange or a parietal cell-specific monoclonal antibody. In the dominant pattern observed, [Ca2+]i was elevated 50-150% and returned within 1-2 min to a value 30-60% over the basal, which was sustained until withdrawal of the stimulant or addition of the gastrin inhibitor L-365,260 (1 microM). The second, but not the first phase, was abolished in the absence of extracellular Ca2+. The results indicate the existence of functional gastrin receptors in a subpopulation of rat parietal cells.


Assuntos
Cálcio/metabolismo , Citosol/metabolismo , Gastrinas/farmacologia , Células Parietais Gástricas/metabolismo , Compostos de Fenilureia , Ácidos/metabolismo , Laranja de Acridina , Animais , Anticorpos Monoclonais , Benzodiazepinonas/farmacologia , Carbacol/farmacologia , Citosol/efeitos dos fármacos , Fura-2 , Gastrinas/antagonistas & inibidores , Histamina/farmacologia , Processamento de Imagem Assistida por Computador , Células Parietais Gástricas/efeitos dos fármacos , Ratos
20.
Acta Physiol Scand ; 144(3): 369-78, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1316714

RESUMO

Two mice DBA/1 were each immunized with a single injection of one million enriched parietal cells in the hind foot pads. Monoclonal antibodies to be used as research tools in studies on regulatory mechanisms in gastric parietal cells were obtained after fusion of mouse myeloma cells (SP2) with cells from the popliteal lymph nodes of the mice. Twelve hybridomas produced antibodies reactive with structures only present in parietal cells as assessed by immunohistochemistry of oxyntic mucosa sections. Three hybridomas were subcloned and the antibodies produced by them, designated as PC4, PC8, and PC117, were characterized. In an enzyme-linked immunosorbent assay, all antibodies reacted with H,K-ATPase-containing vesicles. The antibody PC8 recognized a 94 kDa protein after immunoblotting of H,K-ATPase-containing vesicles and all antibodies precipitated a 94 kDa protein from [125I]H,K-ATPase-containing vesicles. The antibodies PC4 and PC117 recognized extracellular structures with a polarized distribution in viable, purified parietal cells. The results suggest that the structure recognized by all three antibodies is the alpha-subunit of the H,K-ATPase. The antibodies produced by another hybridoma, PC43, recognized a structure present in parietal and surface epithelial cells of the oxyntic mucosa. In an enzyme-linked immunosorbent assay, they reacted with a high-activity carbonic anhydrase which had been affinity-purified from pig oxyntic mucosa and they recognized a 30 kDa protein after immunoblotting. Thus, monoclonal antibodies against both intracellular and extracellular parietal cell structures were obtained after immunization with a small number of parietal cells.


Assuntos
Anticorpos Monoclonais/biossíntese , Células Parietais Gástricas/imunologia , Adenosina Trifosfatases/química , Adenosina Trifosfatases/imunologia , Animais , Antígenos , Anidrases Carbônicas/imunologia , ATPase Trocadora de Hidrogênio-Potássio , Hibridomas/imunologia , Imunização , Imunoquímica , Camundongos , Camundongos Endogâmicos DBA , Células Parietais Gástricas/enzimologia
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