| tazonomy of toxoplasma. | after reviewing reports of the hosts, structure and life cycle of toxoplasma, the genus is placed in the apicomplexan family eimeriidae and the folllowing 7 species are recognized: toxoplasma gondii (nicolle & manceaux) (type species) from about 200 species of mammals and birds, with oocysts in felids; toxoplasma alencari (da costa & pereira) from the frog leptodactylus ocellatus; toxoplasma brumpti coutelen from the iguana iguana tuberculata; toxoplasma colubri tibaldi from the snakes coluber m ... | 1977 | 325203 |
| ion and water balance in isolated epithelial cells of the abdominal skin of the frog leptodactylus ocellatus. | | 1973 | 4127542 |
| ion and water balance in the epithelium of the abdominal skin of the frog leptodactylus ocellatus. | | 1973 | 4752453 |
| cell mediated immune response of bufo arenarum and leptodactylus ocellatus (amphibia, anura) to mycobacterial antigens. | the lymphocyte transformation test was applied to the study of cell mediated immune (cmi) response in vitro to mycobacterial antigens in bufo arenarum and leptodactylus ocellatus previously inoculated with a suspension of mycobacterium tuberculosis. the stimulated samples of blood both in b. arenarum and l. ocellatus showed a significant increase in the percent of blastic dedifferentiation (almost 100% with respect to controls) suggesting the presence of a positive cmi response to ppd. the diffe ... | 1984 | 6141025 |
| some corrections of coccidian (apicomplexa: protozoa) nomenclature. | the following nomenclatural corrections and changes are introduced for the coccidia. new species: cryptosporidium rhesi from the rhesus monkey macaca mulatta; cryptosporidium serpentis from the snakes elaphe guttata, elapha subocularis, crotalus horridus, and sanzinia madagascarensis; eimeria perazae from the lizard cnemidophorus l. lemniscatus; and eimeria tarichae from the salamander taricha toirosa. new combinations: orcheobius carinii for cariniella carinii from the frog leptodactylus ocella ... | 1980 | 7463253 |
| [serum and hypophyseal profiles of alpha-melanotropin and prolactin during the reproductive cycle of leptodactylus ocellatus]. | in this work, the seric and hypophysial concentrations of the hormones alpha-melantopin and prolactin of male specimens of leptodactylus ocellatus from the province of cordoba are studied during a complete annual period. this amphibian presents a continuous reproductive cycle with a wave of greater spermatogenic activity in early summer months (december-january). the results corresponding to hormones show a very similar pattern: both present their maximal seric value in the december-january peri ... | 1995 | 8580514 |
| ocellatins: new antimicrobial peptides from the skin secretion of the south american frog leptodactylus ocellatus (anura: leptodactylidae). | the emergence, in recent years, of microbial resistance to commonly used antibiotics has aroused a search for new naturally occurring bactericidal and fungicidal agents that may have clinical utility. in the present study, three new antimicrobial peptides were purified from the electrical-stimulated skin secretion of the south american frog leptodactylus ocellatus by reversed-phase chromatographic procedures. ocellatin 1 (1gvvdilkgagkdllahlvgkisekv25-conh2), ocellatin 2 (1gvldifkdaakqilahaaekqi2 ... | 2004 | 15648972 |
| chytrid fungus parasitizing the wild amphibian leptodactylus ocellatus (anura: leptodactylidae) in argentina. | the present contribution is the first report of parasitosis by a chytrid fungus in wild anuran amphibians in argentina, as well as the first case of amphibian mortality documented to date in argentina. we report the presence of the chytrid fungus in dead adult leptodactylus ocellatus. it has been suggested that chytridiomycosis is the main cause of death in several amphibian populations worldwide. our study demonstrates that chytridiomycosis afflicts l. ocellatus, a common widespread amphibian s ... | 2005 | 15997823 |
| purification, characterization and homology analysis of ocellatin 4, a cytolytic peptide from the skin secretion of the frog leptodactylus ocellatus. | neobatrachia is the amphibian suborder with the largest number of species and a most important source of bioactive peptides from frog skin secretions. however, 90% of the studies on this subject have been focused on the frog families hylidae and ranidae, while very little is known about peptides of other families, like leptodactylidae. our work reports for the first time the isolation and characterization of ocellatin 4 (glldfvtgvgkdifaqlikqi-nh(2)), a cytolytic peptide from the skin secretion o ... | 2007 | 17884127 |
| leptodactylus ocellatus (amphibia): mechanism of defense in the skin and molecular phylogenetic relationships. | amphibian antimicrobial peptides have been known for many decades and several of them have already been isolated. however, the number of species investigated is still small. herein, we report on the skin secretions of leptodactylus ocellatus, which were extracted by mild electrical stimulation and its semi-preparative reverse-phase chromatography was resolved in more than 30 fractions. among these fractions, two novel antimicrobial peptides were isolated and their amino acid sequences determined ... | 2010 | 19739090 |
| the in vivo effect of low body temperatures on the degree of polymerization of tubulin in brain and testes: a comparison among some species of vertebrates. | the tubulin of both brain and testes of the amphibian bufo spinulosus, leptodactylus ocellatus and odontophrynus occidentalis and of the fish salvelinus fontinalis were partially depolymerized when the animals were maintained on ice for 90 min. recovery of the animals at room temperature restored the normal degree of polymerization in both organs. the cerebral tubulin of the saurian phymatura palluma and of the mammalian myotis chiloensis instead, were not depolymerized in these conditions. the ... | 2002 | 2869871 |
| positive darwinian selection results in resistance to cardioactive toxins in true toads (anura: bufonidae). | members of the family bufonidae, true toads, are famous for their endogenously synthesized cardioactive steroids that serve as defensive toxins. evolution of resistance to these toxins is not understood. we sequenced a key region of the toxin's binding site in the na(+)/k(+) atpase for relevant taxa representing hyloidea (including bufonids), ranoidea and archaeobatrachia and tested for positive selection in a phylogenetic context. bufonidae were distinct from other hyloidea at 4-6 of 12 sites a ... | 2009 | 19465576 |
| isolation and in vitro culture of trypanosomes from leptodactylus ocellatus from the atlantic forest in a new experimental culture medium. | the purpose of this study was to verify the in vitro development of trypanosoma sp. isolated from leptodactylus ocellatus frogs under a new protocol using a biphasic medium composed of novy, mcneal, and nicolle (nnn) blood agar medium as a solid phase and liver infusion, brain heart infusion, and tryptose (libhit) medium as a liquid phase. blood forms, collected by cardiac puncture or after the maceration of different organs, were inoculated in culture tubes containing the biphasic medium compos ... | 2013 | 22694360 |
| [catadiscus eldoradiensis n. sp., trematoda, paramphistomata of leptodactylus ocellatus]. | | 1964 | 14328832 |
| evaluation of the use of leptodactylus ocellatus (anura: leptodactylidae) frog tissues as bioindicator of metal contamination in contas river, northeastern brazil. | this paper presents a study on the viability of the use of tissues of the leptodactylus ocellatus species (anura leptodactylidae) as a bioindicator of metal pollution. the study is based on the determination and correlation of the concentrations of manganese, chromium, zinc, nickel, copper and iron in sediments and tissues (skin, muscles and viscera) of the frog leptodactylus ocellatus collected in the middle region of the contas river in bahia, brazil. the highest levels of the metals studied w ... | 2014 | 25590699 |
| evaluation of the use of leptodactylus ocellatus (anura: leptodactylidae) frog tissues as bioindicator of metal contamination in contas river, northeastern brazil. | this paper presents a study on the viability of the use of tissues of the leptodactylus ocellatus species (anura leptodactylidae) as a bioindicator of metal pollution. the study is based on the determination and correlation of the concentrations of manganese, chromium, zinc, nickel, copper and iron in sediments and tissues (skin, muscles and viscera) of the frog leptodactylus ocellatus collected in the middle region of the contas river in bahia, brazil. the highest levels of the metals studied w ... | 2014 | 25352369 |
| reduced body condition and enzymatic alterations in frogs inhabiting intensive crop production areas. | parameters indicative of general condition and health were compared amongst adult frogs inhabiting uncultivated lands and fields subjected to agricultural practices typical of the humid pampas of argentina. whereas no significant differences existed in the parasite load and external malformations prevalence rate of adult frogs from either environments, a reduced condition factor was clearly demonstrated in frogs from agricultural lands. this conclusion was reached for four frog species of differ ... | 2011 | 21550114 |
| a proposed nomenclature for antimicrobial peptides from frogs of the genus leptodactylus. | it is proposed that the current nomenclature by which individual antimicrobial peptides from the skins of frogs belonging to the genus leptodactylus are named from the species of frog from which they were isolated should be replaced by one that emphasizes the fact that these peptides are evolutionarily related. as the ocellatins from leptodactylus ocellatus were the first such peptides to be characterized, it is suggested that all orthologous peptides should be described as "ocellatins". consist ... | 2008 | 18539359 |
| experimental test of intraspecific competition mechanisms among tadpoles of leptodactylus ocellatus (anura: leptodactylidae). | intraspecific competition is predicted to strongly influence species abundance and dynamics through two main mechanisms: consumption and interference of resources. tadpoles were used in experiments in which we tried to elucidate the relative importance of each mechanism. our goal was to apply this experimental procedure to leptodactylus ocellatus, a common south american anuran, a species whose larvae exhibit aggregative behavior and receive parental care. previous work suggests that tadpole sch ... | 2008 | 18393565 |
| relationship between steroidogenesis and spermiation in rana catesbeiana and leptodactylus ocellatus. | the present study employs an in vitro system to analyse the role of steroid hormones in hcg-induced spermiation in two species of anuran amphibian: rana catesbeiana and leptodactylus ocellatus. in vitro spermiation was induced with 10 iu hcg and the effect of different steroid-biosynthesis inhibitors was analysed. cyanoketone (10(-5)m), an inhibitor of 3-oxo-4-ene steroid biosynthesis, did not block hcg-inducing activity even when biosynthesis of androgen was significantly reduced. these results ... | 2006 | 16552601 |
| caffeine-induced depolarization in amphibian skeletal muscle fibres: role of na+/ca2+ exchange and k+ release. | caffeine (4 mm) produces a depolarization of about 10 mv in frog muscle fibres (leptodactylus ocellatus). the aim of this work was to study the mechanisms of this effect. an approximately threefold rise in membrane resistance [cl--free (so(4)2-) medium] substantially increased, and both na+-free medium and ni2+ (5 mm) reduced, the caffeine-induced depolarization. in voltage-clamped (-60 mv) short fibres from lumbricalis muscle of the toad (buffo arenarum), caffeine generated an inward current of ... | 2001 | 11421861 |
| characteristics of na(+)-ca2+ exchange in frog skeletal muscle. | 1. fluxes studies were carried out to investigate the na(+)-dependent outward movement of ca2+ in intact frog sartorius muscle from leptodactylus ocellatus, a preparation for which published data on the subject are sparse. 2. under normal resting conditions the na(+)-ca2+ exchange was not readily detectable. 3. when muscles were exposed to 4 mm caffeine, the rate of fractional loss of ca2+ (kca,o) increased by about 50%. most of this increase exhibits characteristics typical of the na(+)-ca2+ an ... | 1995 | 7473224 |
| histological, histochemical and ultrastructural study of the hepatic pigment of the frog, leptodactylus ocellatus, l. | | 1987 | 3630338 |
| [localization of chlorine barrier by transepithelial transient electric potentials in rana skin]. | the localization of the outermost barrier to chloride influx in the abdominal skin of leptodactylus ocellatus was investigated by a technique developed by kidder et al. the method analyses the transient changes in transepithelial electrical potential differences produced when an impermeable anion (so4(2) or gluconate) is rapidly replaced by cl in the external bathing solution. the experimental results indicate that the cl barrier is at the same level as the external na barrier, that is, at the o ... | 1983 | 6678103 |
| studies on chloride permeability of the skin of leptodactylus ocellatus: iii. na+ and cl- effect on electrical phenomena. | during their flux through the skin of the frog leptodactylus ocellatus, na+ and cl- interact with each other. this interaction gives rise to electrical phenomena which are studied in the present paper. the skin is mounted in na2so4 ringer's with 115 mm na+ on the inside, and a variety of outer solutions. the osmolarity of all solutions is kept constant at 237.8 mosmol by adding sucrose. when the main anion used on the outside is so=4 the electrical potential difference (deltapsi) rises steadily ... | 1978 | 702521 |
| studies on chloride permeability of the skin of leptodactylus ocellatus: ii. na+ and cl- effect of inward movements of cl-. | at low concentration (1 mm) of cl- in the outer solution, the influx of chloride through the isolated skin (jcl13) of the south american frog leptodactylus ocellatus (l.) seems to be carried by two mechanisms: (i) a passive one that exhibits the characteristics of an exchange diffusion process, and (ii) an active penetration. studies of the influx and efflux of chloride (jcl13 and jcl31) indicate that the presence of a high (107 mm) concentration of cl- in the outer solution activates the transl ... | 1978 | 702520 |
| studies on chloride permeability of the skin of leptodactylus ocellatus: i. na+ and cl- effect on passive movements of cl-. | the outflux of chloride through the isolated skin (jcl31) of the south american frog leptodactylus ocellatus (l.) is carried by a mechanism that saturates at high concentration of chloride on the inside, and is stimulated by the presence of cl- in the outer solution (trans side). the presence of na+ on the outside, by itself, does not increase jcl31. however, when jcl31 is already increased by chloride on the trans side, the addition of na+ produces a significant further increase. at low concent ... | 1978 | 702519 |
| reversible inhibition of potassium contractures by optical isomers of verapamil and d 600 on slow muscle fibres of the frog. | potassium-induced contractures were measured isometrically in slow fibres of gastrocnemius muscle from the frog leptodactylus ocellatus. optical isomers of verapamil and of d 600 decreased the tension of k-contractures with the following characteristics: 1. 90 min exposures of the muscles to the (-)isomers of the drugs were more effective in decreasing tension of 40 mm kcl-contractures when successive challenges to 40 mm kcl were made each 10-15 min than without challenges during the incubation ... | 1976 | 819850 |
| effect of furosemide on the permeability to cl of the isolated skin of leptodactylus ocellatus. | furosemide added to the ringer solution bathing the external side of the isolated skin of leptodactylus ocellatus increased the pd and scc and inhibited both active chloride influx and passive chloride efflux. the action on chloride permeability is thought to contribute to the diuretic effect of the drug. | 1975 | 1204783 |
| ionic fluxes in isolated epithelial cells of the abdominal skin of the frog leptodactylus ocellatus. | unidirectional ion fluxes are measured in cells isolated by a trypsination-dissection method from the epithelium of the frog leptodactylus ocellatus. potassium seems to be contained in a single cellular compartment. the influx of potassium is 0.0068 mumole min-1 mg-1 of dry weight and is carried by a ouabain-sensitive pump. sodium seems to be contained in two cellular compartments, one of which does not exchange its na within the experimental period. the possibility that these compartments refle ... | 1975 | 1159779 |
| net clminus flux in short-circuited skin of rana pipiens: ouabain sensitivity and na+ +k+ dependence. | skin of rama pipiens, like many other species, is considered to actively transport only na+ when bathed in ringer's solution on both sides. however, net clminus influx was previously described by us in short-circuited skin of rana pipiens, in the summer season. the skins were of low pd (5-30 mv) and high clminus conductance. comparison of these findings with other series indicated inverse seasonal variation between pd and clminus conductance. it was postulated that active clminus transport exist ... | 1975 | 1078979 |
| the effect of antidiuretic hormone on na movement across frog skin. | 1. the effect of antidiuretic hormone (adh) on the movement and distribution of na was studied. this was done using three different approaches: (a) the measurement of na and (22)na in slices of epithelium of skins which were exposed to ringer of varied composition containing (22)na, (b) the measurement of the influx of na from the outer to the inner bathing solution with (22)na added to the outside, and (c) the use of a recently introduced technique which permits the direct evaluation of the flu ... | 1971 | 5575333 |
| electrical membrane constants of sartorius muscle fibers from the south american frog, leptodactylus ocellatus. | | 1970 | 5478633 |
| the effect of sodium concentration on the content and distribution of sodium in the frog skin. | 1. the content and distribution of sodium in the epithelium of the frog skin (leptodactylus ocellatus l.) have been studied.2. the inulin space, the (22)na exchange, and the amounts of water and sodium were measured in samples of connective tissue. the results indicate that the necessary assumptions generally made to calculate the sodium and water contents of the epithelial cells as the difference between the total content in the tissue and the amounts contained in the inulin space are not valid ... | 1968 | 5653885 |
| sodium uptake and ammonia excretion through the in vivo skin of the south american frog leptodactylus ocellatus (l., 1758). | | 1968 | 5650603 |
| in vivo ionic exchange through the skin of the south american frog, leptodactylus ocellatus. | | 1968 | 5657206 |
| dna replication patterns in somatic chromosomes of leptodactylus ocellatus (amphibia, anura). | | 1967 | 6077849 |
| [contributions to the histochemical characteristics of the enterochromaffin cell system. iv. the cutaneous venom granules of leptodactylus ocellatus]. | | 1966 | 4968871 |
| the origin of the short-circuit current in the isolated skin of the south american frog leptodactylus ocellatus. | in isolated skins of leptodactylus ocellatus the short-circuit current is smaller than the sodium net flux and this difference disappears when the skins are bathed in solutions in which the chloride ions have been replaced by sulfate or methylsulfate ions. there is a net movement of chloride ions from outside to inside of the skins in the short-circuit condition with chloride ringer's solutions bathing the skins. the addition of ouabain to the inside solution markedly reduced not only sodium net ... | 1963 | 14080822 |
| [pharmacology of arterial pressure in the frog "leptodactylus ocellatus". inconsistent effect of adrenaline]. | | 1961 | 13758154 |
| effects of calcium-free solutions on membrane-potential of myelinated nerve fibers of the brazilian frog leptodactylus ocellatus. | | 1956 | 13331330 |
| [spermiation by phenolic amines in leptodactylus ocellatus (l.) gir]. | | 1955 | 13277292 |
| [phenolic amine-induced spermiation in the frog leptodactylus ocellatus]. | | 2013 | 13273812 |