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Sample records for bufo arenarum skin

  1. Determinants of Instrumental Extinction in Terrestrial Toads ("Bufo arenarum")

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    Muzio, Ruben N.; Ruetti, Eliana; Papini, Mauricio R.

    2006-01-01

    Previous research in a water-reinforced instrumental training situation with toads ("Bufo arenarum") has shown that performance in both acquisition and extinction is poorer after partial, rather than continuous reinforcement training. In Experiment 1, the performance of a group receiving 24 trials on a 50% partial reinforcement schedule was poorer…

  2. [Studies of oogenesis in Bufo arenarum (author's transl)].

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    Valdez Toledo, C L; Pisanó, A

    1980-01-01

    Based on a series of macroscopic and histological observations, during an annual cycle, the main stages of oogenesis in Bufo arenarum (Hensel) have been recognized, pointing out the most significant features. The analysis has established five characteristic stages which permit the individualization of the maturation stage of the oocyte in the ovary. All the information obtained has provided the possibility of drawing up a synthetic table so that the oogenetic stages of this amphibian species, very much used in Argentine experimentation, could be easily recognized.

  3. Polyspermy in Bufo arenarum oocytes matured in vitro.

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    Oterino, J; Sánchez Toranzo, G; Zelarayán, L; Bühler, M I

    1997-08-01

    Full-grown ovarian oocytes of the amphibian Bufo arenarum were induced to mature in vitro by removing the follicular layers (spontaneous maturation) or by treatment with progesterone (hormone-induced maturation). These oocytes were then treated with trypsin and inseminated with homologous spermatozoa. Oocytes matured in vivo that had not undergone any influence of the oviducts (coelomic oocytes), inseminated under the same experimental conditions, were used as controls. The results show that oocytes induced to mature in vitro and exhibiting apparently normal signs of activation were polyspermic. In fact, 2 h after insemination numerous functioning pronuclei could be observed in the animal hemisphere. These results suggest that even though the oocytes which matured in vitro were able to undergo activation after insemination, they were unable to establish an effective block to polyspermy.

  4. The envelopes of amphibian oocytes: physiological modifications in Bufo arenarum

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    Sánchez Mercedes

    2003-02-01

    Full Text Available Abstract A characterization of the Amphibian Bufo arenarum oocyte envelope is presented. It was made in different functional conditions of the oocyte: 1 when it has been released into the coelomic cavity during ovulation (surrounded by the coelomic envelope, (CE, 2 after it has passed through the oviduct and is deposed (surrounded by the viteline envelope, (VE, and 3 after oocyte activation (surrounded by the fertilization envelope, (FE. The characterization was made by SDS-PAGE followed by staining for protein and glycoproteins. Labeled lectins were used to identify glycosidic residues both in separated components on nitrocellulose membranes or in intact oocytes and embryos. Proteolytic properties of the content of the cortical granules were also analyzed. After SDS-PAGE of CE and VE, a different protein pattern was observed. This is probably due to the activity of a protease present in the pars recta of the oviduct. Comparison of the SDS-PAGE pattern of VE and FE showed a different mobility for one of the glycoproteins, gp75. VE and FE proved to have different sugar residues in their oligosaccharide chains. Mannose residues are only present in gp120 of the three envelopes. N-acetyl-galactosamine residues are present in all of the components, except for gp69 in the FE. Galactose residues are present mainly in gp120 of FE. Lectin-binding assays indicate the presence of glucosamine, galactose and N-acetyl galactosamine residues and the absence (or non-availability of N-acetyl-glucosamine or fucose residues on the envelopes surface. The cortical granule product (CGP shows proteolytic activity on gp75 of the VE.

  5. Cell mediated immune response of Bufo arenarum and Leptodactylus ocellatus (Amphibia, Anura) to mycobacterial antigens.

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    Fliess, E L; Salibian, A

    1984-01-01

    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 differences were observed on the fifth day of incubation and lasted until the seventh day.

  6. Estereoultraestructura del pulmón de anuros bufónidos. Bufo arenarum

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    Hermida, Gladys N.

    1994-01-01

    Full Text Available Scanning electron microscopy was used to determined the inner morphology of the Bufo arenarum lung. The observations let conclude that the lung presents three types of folds which divide the organ into alveolar spaces. The inner surface of the lung, as well as the lateral wall of the folds are lined with respiratory epithelium, except in the apex of the primary folds (ciliated surface with goblet cells and in the secondary folds (ciliated surface.

  7. Anomalías oculares en híbridos Bufo paranecmis ♂ x Bufo arenarum ♀ (Anura: Bufonidae

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    Rengel, Dora

    1994-01-01

    Full Text Available Los híbridos entre Bufo paracnemis x Bufo arenarum se encuadran en los llamados "híbridos vitales". Los resultados han evidenciado relevantes anomalías oculares que se manifiestan en un 90% de los casos. En algunas larvas falta el cristalino tanto en uno como en ambos ojos (20%; en otras larvas el cristalino se encuentra ubicado en posición opuesta al normal (25% o bien puede ocurrir que se forme un ojo normal y el otro de forma distinta (20%. El análisis histológico mostró anomalías en la zona retiniana, evidenciándose a partir de los estratos pigmentarios, repliegues y movimientos flexuosos (5%. También existen ojos replegados sobre sí mismos (5%. Las alteraciones más severas llevaron a procesos de anoftalmia (10%. En ocasiones (5% en lugar del ojo se evidencian grumos de pigmento. Se obtuvo un 10% con ojos normales. Los otros órganos presentan analogía con los de las larvas de Bufo paracnemis, inclusive la librea dorsal. The hybrids between Bufo paracnemis x Bufo arenarum are counted among tbe so called "vital hybrids". Our results have revealed relevant ocular anomalies in 90% of cases. In some larvae the lens is lacking in either one or both eyes (20%; in others the lens it is found in an opposite position to normal (25% or else one normal and one different eye is formed (20%. Histological analysis reveals anomalies in the retinal area, observing flexuous movements in the pigmentary strata (5%. Eyes folded over themselves were also observed (5%. The most severe alterations produced cases of anophtalmia (10%. On occasions (5%, groupings of pigments were found instead of the eyes. l0% of the larvae were normal. The other organs show analogies to those of the larvae of Bufo paracnemis, including the dorsal pattem.

  8. The arsenic action during the Bufo arenarum gonad development (Anura: Bufonidae

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    Rengel, Dora

    1991-01-01

    Full Text Available Bufo arenarum ovulations have been kept in potassium bibasic arsenate from the fertilization until 26mm larva. The gonad in development, in the presence of the toxic, suffers significant alterations in its volume, shape and structure. It does not have the typical naillike morphology; on the other hand, it is presented as a spherical mass of reduced volume, that has, as demostrated by the histological analysis, very few oocytes or gonia submerged in a very scarce quantity of stroma. The hypothesis of this study was that it would be due to a succession of events whose cause would lie on the damage that the arsenic determine at the somatic layers level.

  9. Vitellogenesis in Bufo arenarum: Identification, characterization and immunolocalization of high molecular mass lipovitellin during oogenesis

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    O’Brien, Emma D.; Salicioni, Ana M.; Cabada, Marcelo O.; Arranz, Silvia E.

    2009-01-01

    Vitellogenin (Vtg), a large lipoglycophosphoprotein, is the most important precursor of the yolk proteins, and the major source of nutrients for the developing embryo in oviparous species. After its uptake by the oocytes, Vtg is converted into lipovitellins (high and light) and phosvitin, which are deposited into crystalline yolk platelets. We describe here the presence of two high molecular mass lipovitellins isoforms in Bufo arenarum mature oocytes with masses of 113 and 100 kDa, respectively. The amino acid sequence analysis of p113 and p100 peptides showed a high sequence homology between both polypeptides and the complete reported sequences of Xenopus laevis vitellogenin. Using specific antibodies, we determined that the Vtg uptake begins early during oogenesis, at the previtellogenic stage, and continues until oocytes have reached their mature status. In addition, we found that large endocytic vesicles mediate Vtg uptake in stage I oocytes, and that the size of the endocytic vesicles declines with oogenesis progression. In terms of the Vtg protein trafficking, we detected the Vtg precursor (190 kDa) in the liver of estradiol-injected females. Finally, we propose a subclassification of B. arenarum stage-II oocytes into three physiologically and morphologically distinct periods (early, mid and late). PMID:19932187

  10. Expression of phosphatidylcholine biosynthetic enzymes during early embryogenesis in the amphibian Bufo arenarum.

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    Fernández-Bussy, Rodrigo; Mouguelar, Valeria; Banchio, Claudia; Coux, Gabriela

    2015-04-01

    In the principal route of phosphatidylcholine (PC) synthesis the regulatory steps are catalysed by CTP:phosphocholine cytidylyltransferase (CCT) and choline kinase (CK). Knock-out mice in Pcyt1a (CCT gene) and Chka1 (CK gene) resulted in preimplantation embryonic lethality, demonstrating the essential role of this pathway. However, there is still a lack of detailed CCT and CK expression analysis during development. The aim of the current work was to study the expression during early development of both enzymes in the external-fertilization vertebrate Bufo arenarum. Reverse transcription polymerase chain reaction (RT-PCR) and western blot confirmed their presence in unfertilized eggs. Analysis performed in total extracts from staged embryos showed constant protein levels of both enzymes until the 32-cell stage: then they decreased, reaching a minimum in the gastrula before starting to recover. CTP:phosphocholine cytidylyltransferase is an amphitropic enzyme that inter-converts between cytosolic inactive and membrane-bound active forms. Immunoblot analysis demonstrated that the cytosolic:total CCT protein ratio does not change throughout embryogenesis, suggesting a progressive decline of CCT activity in early development. However, PC (and phosphatidylethanolamine) content per egg/embryo remained constant throughout the stages analysed. In conclusion, the current data for B. arenarum suggest that net synthesis of PC mediated by CCT and CK is not required in early development and that supplies for membrane biosynthesis are fulfilled by lipids already present in the egg/embryo reservoirs.

  11. Role of phospholipase A2 pathway in regulating activation of Bufo arenarum oocytes.

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    Ajmat, M T; Bonilla, F; Hermosilla, P C; Zelarayán, L; Bühler, M I

    2013-08-01

    Transient increases in the concentration of cytosolic Ca(2+) are essential for triggering egg activation events. Increased Ca(2+) results from its rapid release from intracellular stores, mainly mediated by one or both intracellular calcium channels: the inositol trisphosphate receptor (IP3R) and the ryanodine receptor (RyR). Several regulatory pathways that tailor the response of these channels to the specific cell type have been proposed. Among its many modulatory actions, calcium can serve as an activator of a cytosolic phospholipase A(2) (cPLA2), which releases arachidonic acid from phospholipids of the endoplasmic reticulum as well as from the nuclear envelope. Previous studies have suggested that arachidonic acid and/or its metabolites were able to modulate the activity of several ion channels. Based on these findings, we have studied the participation of the phospholipase A(2) (PLA(2)) pathway in the process of Bufo arenarum oocyte activation and the interrelation between any of its metabolites and the ion channels involved in the calcium release from the intracellular reservoirs at fertilization. We found that addition of both melittin, a potent PLA(2) activator, and arachidonic acid, the main PLA(2) reaction metabolite, was able to induce activation events in a bell-shaped manner. Differential regulation of IP3Rs and RyRs by arachidonic acid and its products could explain melittin and arachidonic acid behaviour in Bufo arenarum egg activation. The concerted action of arachidonic acid and/or its metabolites could provide controlled mobilization of calcium from intracellular reservoirs and useful tools for understanding calcium homeostasis in eggs that express both types of receptors.

  12. Behaviour of the vitelline envelope in Bufo arenarum oocytes matured in vitro in blockade to polyspermy.

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    Oterino, J; Sánchez Toranzo, G; Zelarayán, L; Ajmat, M T; Bonilla, F; Bühler, M I

    2006-05-01

    During activation of amphibian eggs, cortical granule exocytosis causes elaborate ultrastructural changes in the vitelline envelope. These changes involve modifications in the structure of the vitelline envelope and formation of a fertilization envelope (FE) that can no longer be penetrated by sperm. In Bufo arenarum, as the egg traverses the oviduct, the vitelline envelope is altered by a trypsin-like protease secreted by the oviduct, which induces an increased susceptibility of the vitelline envelope to sperm lysins. Full-grown oocytes of B. arenarum, matured in vitro by progesterone, are polyspermic, although cortical granule exocytosis seems to occur within a normal chronological sequence. These oocytes can be fertilized with or without trypsin treatment, suggesting that the vitelline envelope is totally sperm-permeable. Vitelline envelopes without trypsin treatment cannot retain either gp90 or gp96. This suggests that these glycoproteins are involved in the block to polyspermy and that trypsin treatment of matured in vitro oocytes before insemination is necessary to enable vitelline envelopes to block polyspermy. The loss of the binding capacity in vitelline envelopes isolated from B. arenarum oocytes matured in vitro with trypsin treatment and activated by electric shock suggests that previous trypsin treatment is a necessary step for sperm block to occur. When in vitro matured oocytes were incubated with the product of cortical granules obtained from in vitro matured oocytes (vCGP), vitelline envelopes with trypsin treatment were able to block sperm entry. These oocytes exhibited the characteristic signs of activation. These results support the idea that B. arenarum oocytes can be activated by external stimuli and suggest the presence of unknown oocyte surface receptors linked to the activation machinery in response to fertilization. Electrophoretic profiles obtained by SDS-PAGE of solubilized vitelline envelopes from oocytes matured in vitro revealed the

  13. Calcineurin regulates progressive motility activation of Rhinella (Bufo) arenarum sperm through dephosphorylation of PKC substrates.

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    Krapf, Dario; O'Brien, Emma; Maidagán, Paula M; Morales, Enrique S; Visconti, Pablo E; Arranz, Silvia E

    2014-10-01

    Animals with external fertilization, as amphibians, store their sperm in a quiescent state in the testis. When spermatozoa are released into natural fertilization media, the hypotonic shock triggers activation of sperm motility. Rhinella (Bufo) arenarum sperm are immotile in artificial seminal plasma (ASP, resembling testicular plasma tonicity) but acquire in situ flagellar beating upon dilution. However, if components from the egg shelly coat are added to this medium, motility shifts to a progressive pattern. Recently, we have shown that the signal transduction pathway required for in situ motility activation involves a rise in intracellular cAMP through a transmembrane adenylyl cyclase and activation of PKA, mostly in the midpiece and in the sperm head. In this report, we demonstrate that activation of calcineurin (aka PP2B and PPP3) is required for the shift from in situ to progressive sperm motility. The effect of calcineurin is manifested by dephosphorylation of PKC substrates, and can be promoted by intracellular calcium rise by Ca(2+) ionophore. Both phosphorylated PKC substrates and calcineurin localized to the flagella, indicating a clear differentiation between compartmentalization of PKA and calcineurin pathways. Moreover, no crosstalk is observed between these signaling events, even though both pathways are required for progressive motility acquisition as discussed. © 2014 Wiley Periodicals, Inc.

  14. The Effect of UV-B Radiation on Bufo arenarum Embryos Survival and Superoxide Dismutase Activity

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    Herkovits, J.; D’Eramo, J. L.; Fridman, O.

    2006-01-01

    The exposure of Bufo arenarum embryos to 300–310 nm UV-B at a dose of 4,104 Joule/m2 resulted in 100% lethality within 24 hr while 820 Joule/m2 was the NOEC value for short-term chronic (10 days) exposure. The dose response curves show that lethal effects are proportional with the dose and achieve its highest value within 48 hr post exposure. The superoxide dismutase (SOD) activity in amphibian embryos for sublethal UV-B exposures was evaluated by means of UV-B treatments with 273 (A), 820(B), 1368(C) and 1915(D) Joule/m2 at 2 and 5 hours post irradiation. The SOD activity in units/mg protein in A, B, C and D at 2 hr after treatments were 80.72 ± 14.29, 74.5 ± 13.19, 39.5 ± 6.99 and 10.7 ± 1.89 respectively while for control embryos it was 10.88 ± 1.31. At 5 hr after treatments the SOD values were similar to those found in control embryos. The results confirm the high susceptibility of amphibian embryos to UV-B and point out that the SOD activity is enhanced by low doses of UV-B irradiation achieving significantly higher values than in control embryos at 2 hr post exposure. PMID:16823076

  15. The Effect of UV-B Radiation on Bufo arenarum Embryos Survival and Superoxide Dismutase Activity

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    O. Fridman

    2006-03-01

    Full Text Available The exposure of Bufo arenarum embryos to 300-310 nm UV-B at a dose of 4,104 Joule/m2 resulted in 100% lethality within 24 hr while 820 Joule/m2 was the NOEC value for short-term chronic (10 days exposure. The dose response curves show that lethal effects are proportional with the dose and achieve its highest value within 48 hr post exposure. The superoxide dismutase (SOD activity in amphibian embryos for sublethal UV-B exposures was evaluated by means of UV-B treatments with 273 (A, 820(B, 1368(C and 1915(D Joule/m2 at 2 and 5 hours post irradiation. The SOD activity in units/mg protein in A, B, C and D at 2 hr after treatments were 80.72 ± 14.29, 74.5 ± 13.19, 39.5 ± 6.99 and 10.7 ± 1.89 respectively while for control embryos it was 10.88 ± 1.31. At 5 hr after treatments the SOD values were similar to those found in control embryos. The results confirm the high susceptibility of amphibian embryos to UV-B and point out that the SOD activity is enhanced by low doses of UV-B irradiation achieving significantly higher values than in control embryos at 2 hr post exposure.

  16. El ciclo evolutivo experimental de Diphyllobothrium erinaceieuropei en Paracyclops fimbriatus, larvas de Bufo arenarum y caninos Experimental life cycle of Diphyllobothrium erinaceieuropei in Paracyclops fimbriatus, tadpoles of Bufo arenarum and dogs

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    Lucila Venturini

    1989-10-01

    Full Text Available El objetivo del trabajo fue lograr la reproducción experimental del ciclo evolutivo de Diphyllobothrium erinaceieuropei Rudolphi 1819 (Cestoda, Pseudophyllidea con la intervención de Paracyclops fimbriatus y larvas de Bufo arenarum como hospedadores intermediarios y caninos como hospedadores definitivos. Los huevos del parásito se obtuvieron de heces de caninos infectados naturalmente y se conservaron refrigerados en agua. Se incubaron 7 días a 25°C para que desarrollaran los coracidios y se pusieron en recipientes que contenían a los copépodos mencionados. Al cabo de 12 días a 22,6°C (promedio se hallaron procercoides maduros en ellos y se agregaron 10 renacuajos de Bufo arenarum. Estos se examinaron por disección 22, 23, 61 y 107 días después, hallándose en todos 1 o más plerocercoides (Temperatura promedio: 24,9°C. El día 23, de 6 renacuajos se obtuvieron 49 plerocercoides, de los cuales se administraron 28, por vía oral, a una perra. El día 107, 3 de 11 plerocercoides obtenidos de un renacuajo se le dieron a otra perra por la misma vía. Se hallaron huevos del cestode en las heces del primer canino a partir del día 22 posterior a la infección (p.i. y a los 30 días p.i., segmentos de estróbila. En el segundo canino se hallaron huevos a los 30 días p.i..Experiments were performed in order to develop the life cycle of Diphyllobothrium erinaceieuropei Rudolphi 1819 (Cestoda, Pseudophyllidea in Paracyclops fimbriatus and Bufo arenarum as intermediate hosts and dogs as definitive hosts. The eggs of Diphyllobothrium erinaceieuropei from faeces of naturally infected dogs were kept refrigered, in water. In order to obtain coracidiums they were incubated at 25°C, and then were placed in a flask which contained Paracyclops fimbriatus. The copepods were observed to be infected with procercoids 12 days after, (mean temperature 22.6°C and then, ten tadpoles of Bufo arenarum were put into the same flask. The tadpoles were examined

  17. [Isolation and structure identification of chemical constituents from the skin of Bufo bufo gargarizans].

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    Dai, Li-Ping; Gao, Hui-Min; Wang, Zhi-Min; Wang, Wei-Hao

    2007-08-01

    The skin of Bufo bufo gargarizans, originated from Bufo bufo gargarizans Cantor (Bufonidae), is widely used in traditional Chinese medicine for the treatment of hepatoma, lung cancer and etc. The preparation of the aqueous components has significant therapeutic effect against the digestive tract cancer. The water-soluble chemical constituents in the skin of Bufo bufo gargarizans were then investigated to make clear the active compounds. Six compounds were isolated and purified by recrystallization and column chromatography on silica gel and ODS, their structures were elucidated as 4-amido-3-hydroxymethyl-cyclooctylamidezotetra-alpha-furanone (I), bufogargarizanine C (II), bufothionine (III), dehydrobufotenine hydrobromide (IV), suberic acid (V) and succinic acid (VI) on the basis of physicochemical properties and spectral data (UV, IR, 1H NMR, 13C NMR and MS). Of the above compounds, compounds I and II are new compounds and named bufogargarizanine B and C, respectively.

  18. Chromatographic Fingerprint-Bioactivity Relationships of the Antitumor Properties of Bufo bufo gargarizans Skin Extracts.

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    Sun, Lulu; Zhang, Jing; Zhao, Surong; Pan, Qiong; Zhang, Hongmin; Liu, Hao; Zhang, Zhitao

    2016-01-01

    Statistical analyses of high-performance liquid chromatography (HPLC)-based chemical fingerprints of Bufo bufo gargarizans toad skin extracts were integrated with antitumor evaluations as a means to more effectively identify bioactive constituents. Specifically, chemical fingerprints of Bufo bufo gargarizans skin extract samples obtained from ten different regions in China were generated by HPLC, and then subjected to similarity analysis and principal component analysis (PCA). Concurrently, a MCF-7 breast cancer cell model was adopted to obtain the antitumor activity of different toad skin extracts. The chromatographic fingerprint-bioactivity relationships of the Bufo bufo gargarizans extracts were then evaluated by Pearson correlation analysis. The results demonstrated that all skin extract samples inhibited the proliferation of MCF-7 cells to some extent, and that there was a correlation between the chemical fingerprints and the anti-proliferative activity. Bufotalin, bufalin, and cinobufagin, three known components of Bufo bufo gargarizans that were identified in the chemical fingerprints, were highlighted as constituents responsible for the observed bioactivity. The activity of cinobufagin was confirmed by cell viability and colony formation assays using MCF-7 cells. The approach documented here provides a more effective means to associate chemical information on medicinal extracts with the principle components responsible for their bioactivity, and to therefore expedite drug discovery.

  19. Involvement of the dehydroleucodine alpha-methylene-gamma-lactone function in GVBD inhibition in Bufo arenarum oocytes.

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    Sánchez Toranzo, G; López, L A; Martínez, J Zapata; Bühler, M C Gramajo; Bühler, M I

    2010-02-01

    Dehydroleucodine (DhL), a sesquiterpenic lactone, was isolated and purified from aerial parts of Artemisia douglasiana Besser, a medicinal herb used in Argentina. DhL is an alpha-methylene butyro-gamma-lactone ring connected to a seven-membered ring fused to an exocyclic alpha,beta-unsaturated cyclopentenone ring. It has been previously shown that DhL selectively induces a dose-dependent transient arrest in G2 of both meristematic cells and vascular smooth muscle cells. Treatment with DhL induces an inhibition of spontaneous and progesterone-induced maturation in a dose-dependent manner in Bufo arenarum fully grown oocytes arrested at G2, at the beginning of meiosis I. However, the nature of the mechanisms involved in the process is still unknown. The aim of this work was to analyse whether DhL's alpha-methylene-gamma-lactone function is responsible for the inhibition effect on meiosis reinitiation of Bufo arenarum oocytes as well as some of the transduction pathways that could be involved in this effect using a derivative of DhL inactivated for alpha-methylenelactone, the 11,13-dihydro-dehydroleucodine (2H-DhL). The use of 2H-DhL in the maturation promoting factor (MPF) amplification experiments by injection of both cytoplasm with active MPF and of germinal vesicle content showed results similar to the ones obtained with DhL, suggesting that the hydrogenated derivative would act in a similar way to DhL. Pretreatment with DhL or 2H-DhL did not affect the percentage of germinal vesicle breakdown (GVBD) induced by H89, a protein kinase A (PKA) inhibitor, which suggests that these lactones would act on another step of the signalling pathway that induces MPF activation. The fact that both DhL and 2H-Dhl inhibit GVBD induced by okadaic acid microinjection suggests that they could act on the activity of the Myt1 kinase. This idea is supported by the experiments of injection of GV contents in which an inhibitory effect of these lactones on GVBD was also observed. Our

  20. Biological activities of skin and parotoid gland secretions of bufonid toads (Bufo bufo, Bufo verrucosissimus and Bufotes variabilis) from Turkey.

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    Nalbantsoy, Ayse; Karış, Mert; Yalcin, Husniye Tansel; Göçmen, Bayram

    2016-05-01

    Toad glandular secretions and skin extractions contain numerous natural agents which may provide unique resources for novel drug development. Especially the skin-parotoid gland secretions of toads from genus Bufo contain as many as 86 different types of active compounds, each with the potential of becoming a potent drug. In the present study, crude skin-parotoid gland secretions from Bufo bufo, Bufo verrucosissimus and Bufotes variabilis from Turkey were screened against various cancer cells together with normal cells using MTT assay. Furthermore, the antimicrobial properties of skin secretions were tested on selected bacterial and fungal species for assessing the possible medical applications. Antimicrobial activity of skin secretions was studied by determining minimal inhibitory concentration (MIC) in broth dilution method. Hemolytic activity of each skin-secretion was also estimated for evaluating pharmaceutical potential. Both skin-parotoid gland secretions showed high cytotoxic effect on all cancerous and non-cancerous cell lines with IC50 values varying between <0.1μg/ml and 6.02μg/ml. MIC results of antimicrobial activity tests were found to be between 3.9μg/ml and 250μg/ml. No hemolytic activities on rabbit red blood cells at concentrations between 0.5μg/ml and 50μg/ml were observed. In conclusion, skin-parotoid secretions of bufonid toads might be remarkable candidates for anti-cancer and antimicrobial agents without hemolytic activities. Copyright © 2016. Published by Elsevier Masson SAS.

  1. Variación estacional en la proporción relativa de los estadios de la oogénesis en Bufo arenarum (Anura: Bufonidae

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    Echeverría, Dinorah D.

    1994-01-01

    Full Text Available The Anova repeated measure design was used to compare the percentage of oocytes in female toads (Bufo arenarum at stages 1 to 5 and at different physiological ovary periods (or phases: production, before ovulation, after ovulation. Individual comparisons among stages and between phases have been made with the minimum significant difference method at 0.05 probability level. The statistical analysis at percentage of oocytes showed that: a Stages 1 and 2 have few variation. They are the permanent oocytes group. b Stage 3 (late vitelogenesis oocytes are absent previous to the breeding season. Their rate increases in summer and decreases in autumn. The development of oocytes 3 take place afterwards the ovulation. c Stage 4 increases in autumn and disappears in late winter. d Stage 5 sets up as the 18% of the ovulated oocytes. e. Stages 3, 4 and 5 are renewed every year; they are temporary ovarian oocytes.

  2. Antitumor activity of extracts and compounds from the skin of the toad Bufo bufo gargarizans Cantor.

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    Qi, Fanghua; Li, Anyuan; Inagaki, Yoshinori; Kokudo, Norihiro; Tamura, Sumihito; Nakata, Munehiro; Tang, Wei

    2011-03-01

    The skin of the toad Bufo bufo gargarizans Cantor is known to be rich in bufadienolides, peptides and alkaloids. It has been found to be a source of some extracts and biologically active compounds with antitumor activity. Cinobufacini (Huachansu), a Chinese medicine prepared from the dried toad skin, has been widely used in clinical therapy for various cancers in China. Bufadienolides, such as bufalin, cinobufagin, resibufogenin, and telocinobufagin, are the major active compounds derived from the toad skin. They are the maker biologically active compounds of cinobufagin while the antitumor activity of cinobufagin may be due to this kind of components. Experimental research has suggested that cinobufacini and its active compounds (e.g. bufalin and cinobufagin) exhibit significant antitumor activity, including inhibition of cell proliferation, induction of cell differentiation, induction of apoptosis, disruption of the cell cycle, inhibition of cancer angiogenesis, reversal of multi-drug resistance, and regulation of the immune response. Clinical data have indicated that cinobufacini may have effective anticancer activity with low toxicity and few side effects. Data to date suggest it may also enhance quality of life for patients with cancer. Thus, this review briefly summarizes recent studies on the anticancer activity of cinobufacini and some of its active compounds from the skin of the toad Bufo bufo gargarizans Cantor. This might provide additional evidence for further study of the extracts and active compounds from the toad skin in cancer treatment. Copyright © 2010 Elsevier B.V. All rights reserved.

  3. Estudio morfométrico sobre el desarrollo y evolución de las glándulas tiroides durante la metamorfosis de Bufo arenarum

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    Miranda, Leandro Andrés

    1996-01-01

    Full Text Available Se ha estudiado el desarrollo y la evolución de las glándulas tiroideas durante la morfogénesis de Bufo arenarum. Usando diferentes parámetros morfométricos, hemos relacionado el crecimiento y desarrollo larval con el desarrollo de las glándulas tiroideas. Se observó que la longitud total, el peso de las larvas, el volumen glandular tiroideo y el diámetro folicular, aumentan hasta el estadio XV (fin de la prometamorfosis, mientras que el número de folículos y la altura de las células foliculares tiroideas se incrementan hasta el estadio XVII (mitad del clímax metamórfico. Todos estos parámetros disminuyeron considerablemente durante el clímax metamórfico mientras que en animales postmetamórficos se observó un incremento en los valores registrados. En base a los resultados obtenidos concluimos que hay un período de síntesis y almacenamiento de hormonas tiroideas durante el crecimiento larval y un segundo período caracterizado por la liberación de hormonas tiroideas hacia el final de la prometamorfosis y durante el clímax metamórfico. We studied the development and evolution of thyroid glands during Bufo arenarum morphogenesis. Using different morphometric parameters we related larval growth and metamorphosis with thyroid glands development We observed that total length, larval weight, thyroid gland volume and follicle diameter increased until stage XV (end of prometamorphosis, meanwhile the number of follicles and follicle cell height increased until stage XVII (midclimax. All these parameters decreased during metamorphic climax and an increase was observed in postmetamorphic animals. Our results lead us to conclude that during larval growth there is a period of synthesis and store of thyroid hormones. There is a second period characterized by thyroid hormones release during the end of prometamorphosis and metamorphic climax.

  4. The influence of ambient salinity and temperature on lipid metabolism in toad (Bufo bufo) skin. Is phosphatidylethanolamine an endogenous regulator of ion channels?

    DEFF Research Database (Denmark)

    Hansen, H.J.M.; Olsen, Allan Gylling; Willumsen, Niels J.

    1994-01-01

    Incorporation of (32P) phosphate and (14C) acetate into frog (Rana temporaria) skin phospholipids in vitro was positively correlated to skin MR cell density. Transport across toad (Bufo bufo) skin and incorporation into skin phospholipids of the radioactive tracers were independent...

  5. Expression of N-CAM-180 and N-Cadherin during development in two southamerican anuran species (Bufo arenarum and Hyla nana

    Directory of Open Access Journals (Sweden)

    VH Casco

    2009-12-01

    Full Text Available Cadherins and N-CAM are Ca++-dependent and Ca++-independent cell adhesion molecules respectively. These molecules play a key role in morphogenesis and histogenesis. We determined the spatiotemporal pattern of N-cadherin and N-CAM-180 kDa expression by immunohistochemistry during development in two South-American anuran species (Bufo arenarum, toad and Hyla nana, frog. Both N-cadherin and N-CAM were not detectable during early developmental stages. Expression of Ncadherin appeared between the inner and the outer ectoderm layers at stages 19-20. At stages 24 -25, Ncadherin was expressed in the neural tube and the heart. In early tadpoles, N-cadherin expression increased along with the central nervous system (CNS morphogenesis, and reached its maximum level at metamorphic climax stage. N-Cadherin expression was not uniformly distributed. At stage 42, olfactory placodes and retina expressed N-cadherin. Contrary to N-CAM, the strongly myelinated cranial nerves were not labeled. N-Cadherin was present in several mesoderm derivatives such as the notochord, heart and skeletal muscle. The non-neural ectoderm and the endoderm were always negative. Expression of N-CAM appeared first in the neural tube at stages 24-25 and the level of expression became uniform from pre-metamorphic to metamorphic climax tadpoles. At this latter stage, a clear N-CAM immunolabeling appeared in the nerve terminals of pharynx and heart. N-Cadherin and N-CAM were found mainly co-expressed in the CNS from early tadpole to metamorphic climax tadpole. Our results show that the expression of N-CAM and N-cadherin is evolutionary conserved. Their increased expression during late developmental stages suggests that N-CAM and N-cadherin are involved in cell contact stabilization during tissue formation.

  6. Bufadienolides with cytotoxic activity from the skins of Bufo bufo gargarizans.

    Science.gov (United States)

    Li, Bao-Jing; Tian, Hai-Yan; Zhang, Dong-Mei; Lei, Yu-He; Wang, Lei; Jiang, Ren-Wang; Ye, Wen-Cai

    2015-09-01

    Twelve new bufadienolides (1-12), along with fourteen known analogues (13-26) were isolated from the skins of Bufo bufo gargarizans Cantor. Their chemical structures were elucidated on the basis of NMR, HRESIMS and X-ray diffraction analysis. Compound 1 was an unusual bufadienolide with 3,19-epoxy moiety and A/B trans ring junction. Compounds 2-4 were rare bufadienolides possessing 10-H or 10-carboxyl units. All the isolated compounds were tested for their cytotoxic effects on HepG2, A549 and HeLa cells. Six new compounds (2, 3, 5, 6, 10 and 12) displayed significant anti-proliferative activities with IC50 values ranging from 0.049 to 1.856 μM. Arenobufagin (24) exhibited the most potent cytotoxic activity with IC50 value 0.011 μM. In addition, the present data provided more insight into the structure-activity relationships of bufadienolides. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Active urea transport by the skin of Bufo viridis: Amiloride- and phloretin-sensitive transport sites

    Energy Technology Data Exchange (ETDEWEB)

    Rapoport, J.; Abuful, A.; Chaimovitz, C.; Noeh, Z.; Hays, R.M. (Soroka Medical Center, Beersheva (Israel) Albert Einstein College of Medicine, New York, NY (USA))

    1988-09-01

    Urea is actively transported inwardly (J{sub i}) across the skin of the green toad Bufo viridis. J{sub i} is markedly enhanced in toads adapted to hypertonic saline. The authors studied urea transport across the skin of Bufo viridis under a variety of experimental conditions, including treatment with amiloride and phloretin, agents that inhibit urea permeability in the bladder of Bufo marinus. Amiloride (10{sup {minus}4} M) significantly inhibited J{sub i} in both adapted and unadapted animals and was unaffected by removal of sodium from the external medium. Phloretin (10{sup {minus}4} M) significantly inhibited J{sub i} in adapted animals by 23-46%; there was also a reduction in J{sub i} in unadapted toads at 10{sup {minus}4} and 5 {times} 10{sup {minus}4} M phloretin. A dose-response study revealed that the concentration of phloretin causing half-maximal inhibition (K{sub {1/2}}) was 5 {times} 10{sup {minus}4} M for adapted animals. J{sub i} was unaffected by the substitution of sucrose for Ringer solution or by ouabain. They conclude (1) the process of adaptation appears to involve an increase in the number of amiloride- and phloretin-inhibitable urea transport sites in the skin, with a possible increase in the affinity of the sites for phloretin; (2) the adapted skin resembles the Bufo marinus urinary bladder with respect to amiloride and phloretin-inhibitable sites; (3) they confirm earlier observations that J{sub i} is independent of sodium transport.

  8. Properties of a conductive cellular chloride pathway in the skin of the toad (Bufo bufo)

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Kristensen, P

    1978-01-01

    Two types of chloride current response to a step-wise hyperpolarization of the toad skin is demonstrated: (1) An "instantaneous" response observed immediately upon voltage change, and (2) a subsequent slow response, the time course of which is sigmoidal. The slow response is due to an increase......-state phenomenon: In skins hyperpolarized for a few minutes, the "instantaneous" I-V curves show that the chloride pathway in the conducting state allows a large inward chloride current (outward chloride flux) to pass in the voltage range 40 mV greater than V greater than 0 mV. Calculations based on a three...

  9. Chloride transport in toad skin (Bufo viridis). The effect of salt adaptation

    DEFF Research Database (Denmark)

    Katz, U; Larsen, Erik Hviid

    1984-01-01

    The steady-state Cl- current across the skin of Bufo viridis adapted to tap water was found to be rectified. In skins bathed with NaCl Ringer on both sides, a large outward current, carried by influx of Cl-, was observed at a clamping voltage (V) of less than -50 mV (outside of the skin negative......, and apparent leakage conductance was reduced. Application of the phosphodiesterase inhibitor 3-isobutyl-1-methyl-xanthine to skin of fully salt-adapted toads increased the transepithelial Cl- conductance, and the time courses of voltage clamp currents became more like those of water-adapted toads. Apparent...... leakage conductance was increased.(ABSTRACT TRUNCATED AT 400 WORDS)...

  10. The supercritical CO₂ extract from the skin of Bufo bufo gargarizans Cantor blocks hepatitis B virus antigen secretion in HepG2.2.15 cells.

    Science.gov (United States)

    Cui, Xiaoyan; Inagaki, Yoshinori; Wang, Dongliang; Gao, Jianjun; Qi, Fanghua; Gao, Bo; Kokudo, Norihiro; Fang, Dingzhi; Tang, Wei

    2014-02-01

    The skin of Bufo bufo gargarizans Cantor has long been used for the treatment of hepatitis B in China and supercritical carbon dioxide extraction (SC-CO₂) is widely used in extracting active ingredients from natural products. The aim of present study was to assess the anti-hepatitis B virus (HBV) effect of the supercritical CO₂ extract from the skin of Bufo bufo gargarizans Cantor (SCE-BC). Cytotoxicity of SCE-BC was analyzed using an MTT [3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide] assay in HepG2.2.15 cells. The hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), and hepatitis B core-related antigen (HBcrAg) concentrations in cell culture medium were determined by chemiluminescent enzyme immunoassay. HBV mRNA in cells was determined using real-time polymerase chain reaction. SCE-BC concentrations below 10(-2) μg/mL had no significant toxicity to HepG2.2.15 cells. SCE-BC at 10(-4) μg/mL effectively inhibited the secretion of HBeAg by 23.36% on day 6. It was more potent than the positive control lamivudine (100 μg/mL) in terms of the inhibition of HBeAg and HBcrAg secretion on day 6. Consistent with the HBV antigen reduction, HBV mRNA expression was markedly inhibited in comparison to the control when HepG2.2.15 cells were treated with SCE-BC. Moreover, SCE-BC had greater inhibitory activity with respect to HBeAg than to HBsAg. Since HBeAg promotes immune tolerance and persistent infection during HBV infection, the present results suggest that immune tolerance induced by HBeAg might be overcome by SCE-BC. Therefore, SCE-BC warrants further investigation.

  11. Identification and characterization of gastrointestinal hormone immunoreactive cells in the skin and parotoids of Chinese toad Bufo gargarizans.

    Science.gov (United States)

    Wang, Huan; Wu, Yuan-Yuan; Zhang, Rui; Zhu, Xue; Zhang, Sheng-Zhou

    2014-01-01

    The skin and skin secretion of Chinese toad Bufo gargarizans have long been used in traditional Chinese medicine. However, the exact types and location of bioactive substances in Bufo gargarizans skin still have not been fully elucidated. The aim of the study was to investigate the distribution and density of six types of gastrointestinal (GI) hormone immunoreactive (IR) cells in the skin and parotoids of Bufo gargarizans. Immunohistochemistry was used for qualitative and semiquantitative analysis of GI hormone presence in the dorsal and ventral skin, and parotoids of eight adult Chinese toads. Six types of IR cells were found: serotonin (5-HT), glucagon (GLU), gastrin (GAS), somatostatin (SS), pancreatic polypeptide (PP) and neuropeptide Y(NPY) IR cells. They were mainly present in the epidermis and skin glands. 5-HT-IR cells were distributed in all layers of epidermis and glands, with higher density in the glands. Glucagon was prominently expressed in the epidermis and the bottle-shaped glands of parotoids; however, it was not present in the granular glands of skin and parotoids. The distributions of GAS and SS-IR cells were similar since they were present mainly in mucous, granular and bottle-shaped glands, while these cell types were absent in the differentiated glands of parotoids. PP-IR cells were predominant in the granular glands and the bottle-shaped glands. The expression of NPY was high in epidermal stratum granulosum and mucous glands of the dorsal skin, the bottle-shaped glands and differentiated glands of parotoids, while NPY-IR was rarely seen in the granular glands of ventral skin, and not present in the granular glands of dorsal skin and parotoids. The expression of several types of GI hormones in the skin and parotoids of Bufo gargarizans varies depending on tissue and type of glands.

  12. Comparison of toad skins Bufo bufo gargarizans Cantor from different regions for their active constituents content and cytotoxic activity on lung carcinoma cell lines.

    Science.gov (United States)

    Liu, Congyan; Cao, Wei; Chen, Yan; Qu, Ding; Zhou, Jing

    2014-07-01

    The skin of Bufo bufo gargarizans Cantor, rich in bufadienolides, peptides, and alkaloids, has approved pharmacological activity for preliminary anti-liver and lung tumor treatment. However, few studies have systematically focused on the influence of the producing regions on the content and antitumor activity of the active constituents in toad skins. This study aims to compare toad skins obtained from six different regions in China (Jiangsu, Anhui, Henan, Hebei, Jiangxi, and Shandong province) for their bufadienolide and alkaloid content, and their cytotoxic activity on two lung carcinoma cell lines (SPC-A-1 cells and A549 cells). High performance liquid chromatography (HPLC) was used to quantificationally determine four bufadienolides, which included bufotalin, bufalin, cinobufagin, and resibufogenin in toad skins, from six different regions, respectively. In addition, an ultraviolet (UV) spectrophotometer was also employed to identify the content of the total alkaloids using 5-hydroxytryptamine (5-HT) as the reference substance. An MTT assay was performed to compare the antiproliferative effects of the toad skins' ethanolic extracts from the different regions against SPC-A-1 and A549 cells. In this study, the toad skins from Jiangsu province had the highest amount of bufadienolides (472.6 μg/g crude drug) and alkaloids (1.51 mg/g crude drug). Meanwhile, according to the extract, it exhibited the strongest cytotoxic effect against the lung carcinoma cell line (SPC-A-1 cells and A549 cells) with IC50 values of 24.82 ± 0.76 and 23.77 ± 0.63 μg crude drug/mL, respectively. The toad skins that originated from the Jiangsu province, have comparatively greater advantages over samples from other regions as far as active constituent content and potential anti-lung cancer activity is concerned, suggesting that it can be a promising chemotherapeutic agent in lung cancer therapy, in further studies.

  13. [Identification and bactericidal activity of a novel Cathelicidin family member from skin of Bufu bufo gargarizans].

    Science.gov (United States)

    Zhan, Bo; Gao, Yuan-Yuan; Lin, Wei-Ping; Jia, Guang-Tao; Sun, Tong-Yi; Lee, Wen-Hui

    2016-02-01

    The skin transcriptome of Bufu bufo gargarizans was determined by conventional methods. A novel full length cDNA coding for a Cathelicidin precursor was identified by transcriptomic data assembling, annotation and blast search of corresponding data banks. According to the known processing methods of Cathelicidin family members, present reported novel Cathelicidin precursor of B. bufo gargarizans might be cleaved at 2 possible sites of the same precursor and generate both BG-CATH25 and BG-CATH29 as mature molecules. The deduced BG-CATH25 and BG-CATH29 were synthesized with purity>95% to evaluate the properties and bactericidal activities. The secondary structural characteristics of both BG-CATH25 and BG-CATH29 in different solutions were determined by Circular Dichroism (CD) Analysis. CD results indicated that random coil conformation were the main structural elements for both BG-CATH25 and BG-CATH29 in different buffer systems. Antimicrobial activities against tested bacterial strains were carried out by plating method. Both BG-CATH25 and BG-CATH29 showed strong antibacterial activities against Aeromonas hydrophila, with MIC values of 1.25, 10 mg•L⁻¹, respectively. However, both of them showed weak bactericidal activities against human pathogenic bacteria, like Escherichia coli (ATCC25922),Staphylococcus aureus (ATCC25923)and Pseudomonas aeruginosa (ATCC 27853). Copyright© by the Chinese Pharmaceutical Association.

  14. Purification of bufadienolides from the skin of Bufo bufo gargarizans Cantor with positively charged C18 column.

    Science.gov (United States)

    Li, Xiaolong; Guo, Zhimou; Wang, Chaoran; Shen, Aijin; Liu, Yanfang; Zhang, Xiuli; Zhao, Weijie; Liang, Xinmiao

    2014-04-01

    As a kind of promising anticancer compounds, the preparation of bufadienolides is a hot study spot. However, due to the complexity of biological sample, the purification of bufadienolides from a crude sample (toad skin) is a tough work. In this paper, we reported a new way based on positively charged C18 material (XCharge C18) to quickly separate and purify bufadienolides from toad skin. By this method, the different ionic feature of the amino acid conjugated bufadienolides (AACBs) and the free form bufadienolides (AAUBs) was firstly utilized to obtain distinct separation selectivity on the XCharge C18 column. Additionally, the peak tailing problem of AACBs on conventional C18 was resolved and better resolutions were achieved on the XCharge C18, thus, two kinds of bufadienolides on one column were successfully purified respectively. Taking F13 as an example, the method was validated by liquid chromatography-mass spectrometry (LC-MS), and then 4 AACBs as well as 4 AAUBs were simultaneously purified by preparative XCharge C18. In addition, the application of this method in other fractions was also validated. The results suggested that the developed method is a practical and promising tool for efficient separation and purification of bufadienolides from toad skin. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Relation between chloride exchange diffusion and a conductive chloride pathway across the isolated skin of the toad (Bufo bufo)

    DEFF Research Database (Denmark)

    Kristensen, P; Larsen, Erik Hviid

    1978-01-01

    Substitution of chloride in the outside bathing medium of the toad skin with bromide, iodide, nitrate and sulphate leads to a reduction in the apparent exchange diffusion of chloride across this tissue, and also to a reduction of the chloride current recorded during hyperpolarization. A series...... of inhibitors (thiocyanate, furosemide, phloretin, and acetazolamide) also affects chloride exchange diffusion, hyperpolarization current as well as chloride influx during hyperpolarization. Although in some cases, effects on the short circuit current were also observed none of the effects on chloride transport....... On the basis of these findings, and the results reported in the previous paper (Hviid Larsen and Kristensen 1977) it is considered probable that the membrane molecules responsible to chloride exchange diffusion under short circuit conditions, are rearranged under the influence of a hyperpolarizing clamping...

  16. Lack of bufadienolides in the skin secretion of red bellied toads, Melanophryniscus spp. (Anura, Bufonidae), from Uruguay.

    Science.gov (United States)

    Mebs, Dietrich; Wagner, Moritz G; Pogoda, Werner; Maneyro, Raul; Kwet, Axel; Kauert, Gerold

    2007-01-01

    The South-American red bellied toads (Melanophryniscus spp.) belonging to the Bufonidae family contain toxic alkaloids in their skin, predominantly of the pumiliotoxin group. Whole animal methanolic extracts of individual specimens of three species (Melanophryniscus atroluteus, M. devincenzii, and M. montevidensis) were analyzed for the presence of toad specific bufadienolides and indolalkylamines (serotonin derivatives) by HPLC-electrospray (ESI)-MS-TOF. No bufadienolides, but few bufotenines, mainly dehydrobufotenine, were detected in the extracts in variable amounts. The concentration of the dehydrobufotenine in the extracts seems to be species specific. Whereas M. atroluteus and M. montevidensis contain very low or trace amounts, M. devincenzii specimens exhibit high concentrations of this indolalkylamine. In comparison, analysis of extracts from Bufo arenarum (Uruguay) and from B. bufo (Germany) confirmed the presence of bufadienolides as well as of bufotenine derivatives. Tadpoles of both species exhibited a different pattern: extracts from B. arenarum tadpoles contained only dehydrobufotenine, but those from B. bufo tadpoles bufotoxin and two alkylamines. Melanophryniscus toads appear not to be able to compensate the high variability of toxic skin alkaloids by producing defensive bufadienolides.

  17. Control of spatial orientation in terrestrial toads (Rhinella arenarum).

    Science.gov (United States)

    Daneri, M Florencia; Casanave, Emma; Muzio, Rubén N

    2011-08-01

    Three experiments were conducted to determine problem-solving strategies used by toads, Rhinella arenarum (= Bufo arenarum), in spatial learning situations, using water as reward. Experiment 1 showed that toads can acquire a spatial orientation based on a body-centered turn -an internal self-reference cue. Experiment 2 showed that toads can use a fixed landmark (visual cue) as guidance to solve a spatial problem. Experiment 3 determined whether maze learning was based on "body-centered turn" or "guidance". In this case, animals were trained with a fixed visual cue in relation to a body-centered turn (i.e., simultaneously with the internal self-reference cue) and then tested with the visual cue dissociated from positional cues. Toads trained with the combination of a visual cue and a body-centered turn preferred the latter (turn response) when the two sources of information were set in conflict on probe trials. Toads showed behavioral patterns similar to those described in rodents trained under similar condition, thus, suggesting an early evolutionary origin for these problem-solving strategies. PsycINFO Database Record (c) 2011 APA, all rights reserved.

  18. Bufadienolides and polyhydroxycholestane derivatives from Bufo bufo gargarizans.

    Science.gov (United States)

    Wang, Yan-Min; Li, Zong-Yun; Wang, Jing-Jing; Wu, Xi-Yan; Gao, Hui-Min; Wang, Zhi-Min

    2015-01-01

    A new polyhydroxycholestane sulfate ester, 3α,12β,25,26-tetrahydroxy-7-oxo-5β-cholestane 26-O-sulfate (1), was isolated from dried skin of Bufo bufo gargarizans Cantor and its structure was elucidated on the basis of extensive 1D and 2D NMR as well as HR-ESI-MS analysis. A comparison of steroidal metabolite profiles, based on HPLC and LC-MS analyses, indicates that the chemical compositions of the various parts of toads, such as venom, skin and stratum corneum, are significantly different.

  19. A contribution to the intraspecific systematics of Bufo bufo (Linnaeus, 1758) (Amphibia)

    NARCIS (Netherlands)

    Lange, de L.

    1973-01-01

    A biometrical analysis of preserved specimens of Bufo bufo, supplemented by a detailed examination of the shape of the skin warts, was performed in order to ascertain the taxonomic status of the form described as B.b.spinosus. Indications of a N.-S. clinal variation in the formation of wart thorns

  20. Inhibition of Batrachochytrium dendrobatidis Caused by Bacteria Isolated from the Skin of Boreal Toads, Anaxyrus (Bufo) boreas boreas, from Grand Teton National Park, Wyoming, USA.

    Science.gov (United States)

    Park, Shawna T; Collingwood, Amanda M; St-Hilaire, Sophie; Sheridan, Peter P

    2014-01-01

    The chytrid fungus Batrachochytrium dendrobatidis is a significant cause of the worldwide decline in amphibian populations; however, various amphibian species are capable of coexisting with B. dendrobatidis. Among them are boreal toads (Anaxyrus (Bufo) boreas boreas) located in Grand Teton National Park (GTNP) in Wyoming, USA. The purpose of this study was to identify cultivable bacterial isolates from the skin microbiota of boreal toads from GTNP and determine if they were capable of inhibiting B. dendrobatidis in vitro, and therefore might be a factor in the toad's coexistence with this pathogen. Isolates from 6 of 21 genera tested were found to inhibit the growth of B. dendrobatidis. These bacteria represent diverse lineages such as the Gammaproteobacteria, the Betaproteobacteria, and the Bacteroidetes/Chlorobium groups. We propose that these bacteria compete via microbial antagonism with B. dendrobatidis.

  1. Tissue kinetics, ion transport, and recruitment of mitochondria-rich cells in the skin of the toad (Bufo bufo) in response to exposure to distilled water

    DEFF Research Database (Denmark)

    Budtz, Poul Egede; Christoffersen, Betina C.; Johansen, Jesper S.

    1995-01-01

    studied in toads (Bufo bufo) immediately before, and after 2,7, and 14 days exposure to distilled water. General epidermal structure was not affected. However, the numbers of MRCs per mm2 (DMRC) increased throughout the experiment as revealed by staining of epidermal sheets with AgNO3 (Ag) or methylene...... blue (MB). Part of the increased DMRC was accounted for by an increase in MRC subpopulation(s) that stained neither with Ag nor MB. The cell birth rate (Kb) decreased and cell loss by moulting (Kd) increased without any significant change in epidermal cell pool size, indicating a reduced apoptotic rate...

  2. [Bufadienolides from venom of Bufo bufo gargarizans].

    Science.gov (United States)

    Zhang, Peng-Wei; Jiang, Ren-Wang; Ye, Wen-Cai; Tian, Hai-Yan

    2014-03-01

    Twelve compounds were isolated from the venom of Bufo bufo gargarizans. On the basis of their physical and chemical properties and spectral data, their structures were identified as resibufagenin (1), bufotalin (2), desacetylcinobufagin (3), 19-oxodesacetylcinobufotalin (4), cinobufotalin (5), 1beta-hydroxylbufalin (6), 12alpha-hydroxybufalin (7), bufotalinin (8), Hellebrigenin (9), telocinobufagin (10), hellebrigenol (11) and cinobufagin-3-hemisuberate methyl ester (12), respectively. Compounds 7 and 12 are new natural products.

  3. A novel cathelicidin from Bufo bufo gargarizans Cantor showed specific activity to its habitat bacteria.

    Science.gov (United States)

    Sun, Tongyi; Zhan, Bo; Gao, Yuanyuan

    2015-10-25

    Toad Bufo bufo gargarizans Cantor is still used in China as traditional Chinese medicine. However, present investigations on its skin secretions were mainly focused on the bufadienolides, the proteins/peptides contained in the secretions are largely unknown. A cDNA encoding a novel cathelicidin termed BG-CATH was identified by analysis of the toad skin transcriptome. The BG-CATH precursor was predicted to have 2 possible cleavage sites following dibasic cleavage signals at its C-terminal, which will generate two mature peptides, BG-CATH37 and BG-CATH(5-37). Phylogenetic analysis suggests that amphibian cathelicidins might evolve from common ancestors. The two predicted mature cathelicidins from B. bufo gargarizans were synthesized and both of them showed weak antimicrobial activities against human pathogenic bacteria Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus (MIC ≥ 200 μg/mL). However, BG-CATH37 and BG-CATH(5-37) had strong antimicrobial activities against aquatic bacteria of Vibrio splendidus, Streptococcus iniae and Aeromorus hydrophila, which were common microorganisms in the habitat of B. bufo gargarizans (MIC 3.125-40 μg/mL). BG-CATH37 and BG-CATH(5-37) showed no hemolytic activity even at high concentrations (400 μg/mL). CD spectra analysis suggested that structure rigidity of BG-CATH37 and BG-CATH(5-37) might play an important role to regulate their biological activities. Selective antimicrobial activity against habitat microorganisms might reflect the adaptation of amphibians to their living environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. How complex is the Bufo bufo species group?

    Science.gov (United States)

    Arntzen, Jan W; Recuero, Ernesto; Canestrelli, Daniele; Martínez-Solano, Iñigo

    2013-12-01

    Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like ecology and conservation biology. We here review molecular genetic evidence relevant to the systematics of toads in the Bufo bufo species group (Anura, Bufonidae). Two studies recently published in this journal (Recuero et al., MPE 62: 71-86 and García-Porta et al., MPE 63: 113-130) addressed this issue but reached opposing conclusions on the taxonomy of the group (four versus two species). In particular, allozyme data in the latter paper were interpreted as evidence for hybridization across species (between B. bufo-B. spinosus and B. bufo-B. verrucosissimus). We tested claims for hybridization through re-analysis of allozyme data for individuals instead of populations, to be able to distinguish between sympatry with and without admixture, and found no evidence of hybridization across taxa. We propose alternative explanations for the observed patterns that García-Porta et al. (2012) failed to consider. In the absence of unequivocal evidence for hybridization and introgression, we reject the proposal to downgrade Bufo spinosus and Bufo verrucosissimus to the subspecies level. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  5. [Specific features of the melanophore system in different color morphs of larvae of the common toad (Bufo bufo L.)].

    Science.gov (United States)

    Zakharova, L A; Surova, G S; Timofeev, K N

    2012-01-01

    In a natural pond among usual black larvae of the common toad (Bufo bufo L.), a few unusual individuals of red-olive coloring were found out. In both morphs we investigated the melanophores of skin using different methods. The ESR-spectrometric analysis has shown the absence of distinctions between morphs by the amount of melanin. Analysis of total preparations of skin has shown the presence of various kinds of melanophore cells both in the derma and in the epidermis. Among typical melanophores, essentially differing cells appeared (atypical cells). In black morph tadpoles, the number of all kinds of melanophores is significantly greater than in red-olive morphs. It is shown that dark coloring is connected with a considerable number of atypical cells in the epidermis imposed on a dense layer of typical dermal melanophores with dispersed melanin.

  6. Mechanisms of ion transport in the mesonephric collecting duct system of Bufo bufo as revealed by microelectrode recordings in isolated perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2002-01-01

    amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad......amphibian, Ba2+, Bufo bufo, collecting duct, collecting tubule, K+ conductance, K+ secretion, kidney, mesonephros, ouabain, toad...

  7. Retinol-induced apoptosis in larval pancreas of Bufo bufo

    Science.gov (United States)

    Accordi, F; Chimenti, C

    2003-01-01

    Tadpoles of Bufo bufo at the end of premetamorphosis were exposed to the action of retinol diluted in the rearing water at two concentrations: 20 and 40 µm, for 48 h. Assuming that retinol causes growth suppression by cell death induction, the TUNEL reaction for the detection of apoptotic cells was performed on paraffin sections of pancreas. The results showed that retinol induced a significant dose-dependent increase of number of apoptotic cells with respect to controls, in which apoptosis was scarce. Electron microscopic observations of treated specimens showed that the effects of retinol mostly occurred on exocrine cells: condensed crescent-shaped nuclear chromatin, dark cytoplasm with long projections; conversely, mitochondria and endoplasmic reticulum appeared unaffected. PMID:12713271

  8. Assessing atrazine-induced toxicities in Bufo bufo gargarizans Cantor.

    Science.gov (United States)

    Sai, Linlin; Wu, Qingbo; Qu, Binpeng; Bo, Cunxiang; Yu, Gongchang; Jia, Qiang; Xie, Lin; Li, Yuezhong; Guo, Qiming; Ng, Jack C; Peng, Cheng

    2015-02-01

    Atrazine (AZ), a widely used herbicide has drawn attentions for its potential impacts on amphibians. This study aims to investigate the toxicity of AZ in Bufo bufo gargarizans Cantor (B. bufo gargarizans), a species of toad commonly found in China and countries in East Asia. We treated tadpoles with 0.1, 1, 10 and 100 μg/L AZ for 85 days and examined related parameters. The results showed that the mortality of the toads in the treatment group increased dramatically in a U-shaped dose-response relationship. The hindlimb extension and metamorphosis rate of the toads were significantly inhibited by AZ at 10 and 100 μg/L. Under the same condition, there were significant progressive changes in the testicular structures. Moreover, we found that AZ has no significant effects on growth, sex ratios, gonadal morphology, forelimb emergence and histology in the ovaries. Our results support the idea that environmental contaminants including AZ may be relevant to global amphibian decline.

  9. Cromoblastomicosis Experimental en Bufo marinus

    OpenAIRE

    Trejos, A.

    2016-01-01

    Reviewing the observations of CARINI and the experimental work of ALMEIDA and AREA LEAO, MELLO & CURY on the pathogenicity of the etiologic agents of Chromoblastomycosis inyected intraperitonealy in Salientia species Leptodactylus ocellatus and L. pentadactylus, we decided to determine the pathogenicity of Fonsecaeae pedrosoi on Bufo marinus. Six specimens were innoculated with suspensions of cultures of this fungs obtained from six human cases, using one strain per animal.At autopsy, one obs...

  10. C23 steroids from the venom of Bufo bufo gargarizans.

    Science.gov (United States)

    Tian, Hai-Yan; Luo, Shi-Lin; Liu, Jun-Shan; Wang, Lei; Wang, Ying; Zhang, Dong-Mei; Zhang, Xiao-Qi; Jiang, Ren-Wang; Ye, Wen-Cai

    2013-10-25

    Five new C23 steroids (1-5) together with five known bufadienolides (6-10) were isolated from the venom of Bufo bufo gargarizans (ChanSu in Chinese). The structures of the new steroids were elucidated by extensive spectroscopic methods in combination with X-ray diffraction analysis. Among these C23 steroids, only compound 3 showed cytotoxicities against HepG2 and A549 cancer cells, with respective IC50 values of 26.8 ± 8.3 and 45.6 ± 2.5 μM. In contrast, the bufadienolides (7-10) displayed potent inhibitory activities against these cancer cells, with respective IC50 values in the ranges 0.5-5.5 and 0.6-6.5 μM, but relatively less cytotoxicity on normal mouse spleen cells. In addition, the Na(+)/K(+)-ATPase inhibitory activities of 2, 5, and 7 revealed that the lactone moiety of a bufadienolide was important for the inhibitory activity.

  11. Assessment of age and intersexual size differences in Bufo bufo

    Directory of Open Access Journals (Sweden)

    Cvetković Dragana D.

    2005-01-01

    Full Text Available Numerous studies have underlined the complex nature of relationship between age, size, and reproductive traits in anurans. One of the most intriguing problems for evolutionary biologists is intersexual difference in body size (SSD. For testing various hypotheses about SSD, we need reliable estimates of its extent (the important issue being the choice of trait for analysis as well as the accurate determination of individual age. The measures of SSD may be subject to error if estimated from populations with unknown age distribution; amphibians continue to grow throughout their life and SSD is linked to sex differences in traits such as age at maturity and lifespan. In the present paper, we analyze problems involved in accurate determination of age structure and factors that may lead to under- or overestimation of individual age, as well as the problem of appropriate choice of traits, in the light of our experience and results of investigating populations of common toad (Bufo bufo in the vicinity of Belgrade.

  12. Cloning the sterol carrier protein 2 genes of Japanese toad (Bufo japonicus formosus) and Chinese toad (Bufo gargarizans) and its tissue expression analysis.

    Science.gov (United States)

    Ji, Yu-Cheng; Zhuge, Hui; Zhang, Shan-Shan; Zhang, Shu-Fang; Yang, Xian-Yu

    2014-09-01

    In this study, to clarify the bioactive polypeptides included in the skins and secretions of Bufo, we screened the Japanese toad (Bufo japonicus formosus) skin cDNA liary by colony polymerase chain reaction (PCR), and obtained a transcript of 1 075 bp consisting of 1 37 bp 5' untranslated region (UTR), 515 bp 3' UTR and a 423 bp open reading frame (ORF) encoding a polypeptide of 140 amino acid residues (GenBank accession number: KF359945). Homolog analysis showed a 70%-96% homology with sterol carrier protein-2 (SCP-2) present in other animals, which is implicated in lipid metabolism of other organisms. The gene SCP-2 of Chinese toad (B. gargarizans) was cloned from a first strand cDNA of Bufo skin (GenBank accession number: KF381341) via PCR, whose encoding polypeptide has only one amino acid difference from that of Japanese toad. Tissue distribution analysis showed that SCP-2 expressed in all organs tested, though in the liver and spleen it manifested lower expression than in other organs. These findings might indicate SCP-2 being one of the active ingredients in toad skin. These findings may in turn have implications for further drug development from traditional Chinese medicine sources.

  13. Bufospirostenin A and Bufogargarizin C, Steroids with Rearranged Skeletons from the Toad Bufo bufo gargarizans.

    Science.gov (United States)

    Tian, Hai-Yan; Ruan, Li-Jun; Yu, Tong; Zheng, Qing-Fei; Chen, Nan-Hao; Wu, Rui-Bo; Zhang, Xiao-Qi; Wang, Lei; Jiang, Ren-Wang; Ye, Wen-Cai

    2017-04-28

    Bufospirostenin A (1) and bufogargarizin C (2), two novel steroids with rearranged A/B rings, were isolated from the toad Bufo bufo gargarizans. Compound 1 represents the first spirostanol found in animals. Compound 2 is an unusual bufadienolide with a cycloheptatriene B ring. Their structures were elucidated by spectroscopic analysis, single crystal X-ray diffraction analysis, and computational calculations.

  14. Physiological and molecular mechanisms of inorganic phosphate handling in the toad Bufo bufo

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Werner, Andreas; Hansen, Sofie M

    2006-01-01

    The aim of this study was to elucidate mechanisms of P(i) handling in toads (Bufo bufo). We introduced toads to experimental solutions of various [P(i)] and high P(i) diets and measured urine and lymph [P(i)]. Both lymph and urine [P(i)] increased with increasing P(i) loads, indicating P...

  15. Chloride channels in toad skin

    DEFF Research Database (Denmark)

    Larsen, Erik Hviid; Rasmussen, B E

    1982-01-01

    A study of the voltage and time dependence of a transepithelial Cl- current in toad skin (Bufo bufo) by the voltage-clamp method leads to the conclusion that potential has a dual role for Cl- transport. One is to control the permeability of an apical membrane Cl-pathway, the other is to drive Cl-......- transport through open channels does not obey the constant-field equation....

  16. Concentration dependence of halide fluxes and selectivity of the anion pathway in toad skin

    DEFF Research Database (Denmark)

    Harck, A F; Larsen, Erik Hviid

    1986-01-01

    The isolated toad (Bufo bufo) skin was mounted under voltage-clamp conditions in a chamber shown to cause no significant edge damage. The serosal side of the skin was bathed with NaCl-Ringer's, and the passive voltage-sensitive anion conductance studied in its fully voltage activated state, V = -...

  17. Agregace jako antipredační strategie u pulců ropuchy obecné (\\kur{Bufo bufo}).

    OpenAIRE

    Bodnár, Tomáš

    2007-01-01

    Tadpoles of many anuran species use a huge number of behavioral modifications to avoid predators. Reduced activity in presence of predators is favorite strategy for common toad tadpoles (Bufo bufo). Responses against predator cues by tadpoles of Bufo bufo in the presence of another cue of larger tadpole aggregation were tested in this study. We observed that these tadpoles responded differently to predator chemical cues than tadpoles in a small group.

  18. New bufadienolides and C(23) steroids from the venom of Bufo bufo gargarizans.

    Science.gov (United States)

    Tian, Hai-Yan; Wang, Lei; Zhang, Xiao-Qi; Zhang, Dong-Mei; Wang, Ying; Liu, Jun-Shan; Jiang, Ren-Wang; Ye, Wen-Cai

    2010-12-01

    Six new bufadienolides (1-6) and two new C(23) steroids (7 and 8), together with three known compounds (9-11) were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated by spectroscopic analysis and single-crystal X-ray diffraction. In vitro cytotoxicities of all compounds were evaluated in A549 cancer cell line. Compounds 2, 3 and 10 showed significant cytotoxic activities. Copyright 2010 Elsevier Inc. All rights reserved.

  19. A curious case of herbivory in the common toad Rhinella arenarum during hibernation in captivity conditions

    Directory of Open Access Journals (Sweden)

    Pozzi, Andrea Gabriela

    2012-12-01

    Full Text Available El objetivo de la presente nota es documentar un comportamiento curioso ocurrido con un grupo de animales adultos de Rhinella arenarum que fueron mantenidos en condiciones de hibernación artificial en el laboratorio durante abril-julio del 2012.

  20. Cd, Cu, Zn, Se, and metallothioneins in two amphibians, Necturus maculosus (Amphibia, Caudata) and Bufo bufo (Amphibia, Anura).

    Science.gov (United States)

    Dobrovoljc, Katarina; Falnoga, Ingrid; Žnidarič, Magda Tušek; Mazej, Darja; Ščančar, Janez; Bulog, Boris

    2012-12-01

    The accumulation of cadmium, its affinity for metallothioneins (MTs), and its relation to copper, zinc, and selenium were investigated in the experimental mudpuppy Necturus maculosus and the common toad Bufo bufo captured in nature. Specimens of N. maculosus were exposed to waterborne Cd (85 μg/L) for up to 40 days. Exposure resulted in tissue-dependent accumulation of Cd in the order kidney, gills > intestine, liver, brain > pancreas, skin, spleen, and gonads. During the 40-day exposure, concentrations increased close to 1 μg/g in kidneys and gills (0.64-0.95 and 0.52-0.76; n = 4), whereas the levels stayed below 0.5 in liver (0.14-0.29; n = 4) and other organs. Cd exposure was accompanied by an increase of Zn and Cu in kidneys and Zn in skin, while a decrease of Cu was observed in muscles and skin. Cytosol metallothioneins (MTs) were detected as Cu,Zn-thioneins in liver and Zn,Cu-thioneins in gills and kidney, with the presence of Se in all cases. After exposure, Cd binding to MTs was clearly observed in cytosol of gills as Zn,Cu,Cd-thionein and in pellet extract of kidneys as Zn,Cu,Cd-thioneins. The results indicate low Cd storage in liver with almost undetectable Cd in liver MT fractions. In field trapped Bufo bufo (spring and autumn animals), Cd levels were followed in four organs and found to be in the order kidney > liver (0.56-5.0 μg/g >0.03-0.72 μg/g; n = 11, spring and autumn animals), with no detectable Cd in muscle and skin. At the tissue level, high positive correlations between Cd, Cu, and Se were found in liver (all r > 0.80; α = 0.05, n = 5), and between Cd and Se in kidney (r = 0.76; n = 5) of autumn animals, possibly connected with the storage of excess elements in biologically inert forms. In the liver of spring animals, having higher tissue level of Cd than autumn ones, part of the Cd was identified as Cu,Zn,Cd-thioneins with traces of Se. As both species are special in having liver Cu levels higher than

  1. blood glucose level in Bufo gutturalis (power)

    African Journals Online (AJOL)

    a larger study dealing with glucose homeostasis in the toad Bufo gutturalis. Seven groups of seven toads each were acclimatized to laboratory conditions for one month. During this period the toads were fed daily on live insects and were housed in a large laboratory terrarium in which the natural habitat was simulated as ...

  2. Multilocus species tree analyses resolve the radiation of the widespread Bufo bufo species group (Anura, Bufonidae).

    Science.gov (United States)

    Recuero, E; Canestrelli, D; Vörös, J; Szabó, K; Poyarkov, N A; Arntzen, J W; Crnobrnja-Isailovic, J; Kidov, A A; Cogălniceanu, D; Caputo, F P; Nascetti, G; Martínez-Solano, I

    2012-01-01

    New analytical methods are improving our ability to reconstruct robust species trees from multilocus datasets, despite difficulties in phylogenetic reconstruction associated with recent, rapid divergence, incomplete lineage sorting and/or introgression. In this study, we applied these methods to resolve the radiation of toads in the Bufo bufo (Anura, Bufonidae) species group, ranging from the Iberian Peninsula and North Africa to Siberia, based on sequences from two mitochondrial and four nuclear DNA regions (3490 base pairs). We obtained a fully-resolved topology, with the recently described Bufo eichwaldi from the Talysh Mountains in south Azerbaijan and Iran as the sister taxon to a clade including: (1) north African, Iberian, and most French populations, referred herein to Bufo spinosus based on the implied inclusion of populations from its type locality and (2) a second clade, sister to B. spinosus, including two sister subclades: one with all samples of Bufo verrucosissimus from the Caucasus and another one with samples of B. bufo from northern France to Russia, including the Apennine and Balkan peninsulas and most of Anatolia. Coalescent-based estimations of time to most recent common ancestors for each species and selected subclades allowed historical reconstruction of the diversification of the species group in the context of Mediterranean paleogeography and indicated a long evolutionary history in this region. Finally, we used our data to delimit the ranges of the four species, particularly the more widespread and historically confused B. spinosus and B. bufo, and identify potential contact zones, some of which show striking parallels with other co-distributed species. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. The complete mitochondrial genome of Bufo raddei.

    Science.gov (United States)

    Zhang, Wenya; Zhang, Xingjie; Guo, Rui; Tang, Yue; Zhang, Yingmei

    2016-09-01

    The complete mitochondrial genome of Bufo raddei is carried out in the present research using Illumina Hiseq 2500. The mitogenome is 17 602 bp in length and contains 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a D-loop region. The overall base composition of the H-strand is 29.15% for A, 26.09% for C, 15.16% for G, and 29.60% for T. The G + C content is 41.25%. Phylogenetic analyses of B. raddei and other 12 amphibian were carried out using Bayesian phylogenetic methods. The sequences of B. raddei were clustered in genus Bufo.

  4. A New C23 Steroid from the Venom of Bufo bufo gargarizans.

    Science.gov (United States)

    Luo, Shi-Lin; Tian, Hai-Yan; Liu, Jun-Shan; Wang, Ying; Ye, Wen-Cai

    2015-08-01

    A new C23 steroid, (3β,5β,14β)-methyl (3-hydroxy-14,15-epoxy-20-oxo-21-norcholan-24-oate) (1), together with four known ones (2-5), were isolated from the venom of Bufo bufo gargarizans. Their structures were elucidated on the basis of extensive spectroscopic analysis. The cytotoxicity of these compounds was also evaluated against human hepatocarcinoma HepG2 cells. Compound 3 showed significant cytotoxicity with an IC50 value of 16.8 +/- 0.7 μM.

  5. Migrating common toads (Bufo bufo) in rural temperate regions: reservoirs of Salmonella?

    Science.gov (United States)

    Sharifian-Fard, Mojdeh; Pasmans, Frank; Martel, An

    2014-04-01

    Salmonella infections in amphibians are supposedly highly prevalent. Migrating common amphibian species in cultivated areas such as common toads (Bufo bufo) may thus promote spread and zoonotic transfer of Salmonella to humans, both indirectly by crop and livestock contamination and by direct contact. Between February and April 2011, the intestinal content of 1,740 samples of road-killed migrating common toads in five Flemish provinces of Belgium was examined for the presence of Salmonella using bacterial culture and PCR. All the samples were negative. These results suggest that the role of migrating common toads in maintaining the infection cycle of Salmonella in northern European temperate regions is negligible.

  6. Report of Bufo tihamicus karyotype from Saudi Arabia

    African Journals Online (AJOL)

    Abdulaziz

    2013-04-17

    Apr 17, 2013 ... This study gives a description of the Karyotype of the Tihama toad Bufo tihamicus from Saudi Arabia. Samples of males and females of Bufo tihamicus Parker were collected from Gazan Province of. Kingdom of Saudi Arabia. The karyotype consists of a diploid number 2n = 22 and the fundamental number ...

  7. Water-balance response of Rhinella arenarum (Hensel, 1867) tadpoles to graduated increase in environmental osmolarity

    OpenAIRE

    Ferrari,L.; de la Torre,FR.; Salibián,A.

    2010-01-01

    The water balance and the upper limit of osmotic tolerance of premetamorphic Rhinella arenarum larvae (Gosner's stage 26) was evaluated after semistatic incubation in electrolyte (NaCl) and non-electrolyte (mannitol) media following a protocol of progressively increased osmotic pressure. Wet and dry weights were measured to calculate the water content as a derived variable indicative of the hydric balance. Statistical analysis was performed using univariate and integrated multivariate analysi...

  8. Proton pump activity is required for active uptake of chloride in isolated amphibian skin exposed to freshwater

    DEFF Research Database (Denmark)

    Jensen, Lars Jørn; Willumsen, Niels J.; Larsen, Erik Hviid

    2002-01-01

    Net proton secretion and unidirectional chloride fluxes were measured in isolated skin of toads (Bufo bufo) and frogs (Rana esculenta) mounted in an Ussing chamber and exposed to a Ringer's solution on the serosal side and a freshwater-like solution (1-3 mM Cl-) on the external side. Active proto...

  9. Gill alterations as biomarkers of chronic exposure to endosulfan in Bufo bufo tadpoles.

    Science.gov (United States)

    Brunelli, Elvira; Bernabò, Ilaria; Sperone, Emilio; Tripepi, Sandro

    2010-12-01

    Endosulfan sprayed on agricultural fields accumulates in temporary pools due to surface runoff or sediment transport and may result in high water concentrations in spring and summer, coinciding with breeding and crucial stages of amphibian larval development. In the present study, Bufo bufo tadpoles were exposed to three different concentrations of endosulfan (0.01, 0.05 and 0.1 mg/L) until they reached complete metamorphosis. The aim of the study was to investigate the effects of endosulfan, at environmentally relevant concentrations on gill morphology and ultrastructure. Modifications in ultrastructure and cell composition were observed at all concentrations after 96 h. The main gill effects recorded in treated animals were: mucous secretion, the appearance of tubular vesicles cells (TVC) and a degeneration phenomenon. Comparing these results with our previous findings in which we used growth, developmental rate and behaviour as endpoints, we also demonstrated that the first effect of endosulfan on Bufo bufo was gill alteration, thus supporting the role of a morphological approach in toxicological studies. This study provides additional information on the role of morphological studies in demonstrating the effects of exposure to environmental pollutants. In this context, the use of amphibian gills, as effective biomarkers, is a valuable approach in evaluating exposure to agrochemicals.

  10. Final Critical Habitat for the Houston toad (Bufo houstonensis)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Houston toad (Bufo houstonensis) based on the description provided in the Federal...

  11. Environmentally relevant concentrations of endosulfan impair development, metamorphosis and behaviour in Bufo bufo tadpoles.

    Science.gov (United States)

    Brunelli, Elvira; Bernabò, Ilaria; Berg, Cecilia; Lundstedt-Enkel, Katrin; Bonacci, Antonella; Tripepi, Sandro

    2009-01-31

    Endosulfan is a widely used organochlorine pesticide with well-documented neurotoxic effects in both humans and laboratory animals (mammals and fish). Neurotoxicity has been implied also in amphibians after short-term exposure to endosulfan. Little is known about effects of chronic exposure of endosulfan in amphibians. Previously, we examined the short-term toxicity of endosulfan in common toad (Bufo bufo) tadpoles and determined the LC50 value to 0.43 mg/L. In the present study, we investigated the effects of endosulfan on B. bufo tadpoles after chronic exposure to ecologically relevant concentrations. Tadpoles were exposed in a static renewal test, from shortly after hatching (Gosner stage 25) to completed metamorphosis, to 0.01, 0.05 and 0.1mg endosulfan/L (nominal). The exposure period lasted 43-52 days. Mortality, larval growth (mass), development (reached Gosner stage at various times and deformities presence), metamorphosis and behaviour (swimming activity) were monitored regularly over the entire course of larval development. Our results show that 0.05 and 0.1mg endosulfan/L caused impaired behaviour, prolonged time to metamorphosis, increased incidences of mouth and skeletal malformations as well as mortality, and reduced body weight (observed also at 0.01 mg/L) in B. bufo tadpoles. Behavioural effects occurred at exposure day 4, before any other effects occurred, indicating a neurotoxic effect. Endosulfan levels found in groundwater and surface water range from 0.1 to 100 microg/L and after extraordinary runoff events, concentrations exceed 0.5 mg/L in surface water. Our results indicate that endosulfan may negatively affect wild frog populations in agricultural areas.

  12. Molecular phylogenetics and historical biogeography of the west-palearctic common toads (Bufo bufo species complex).

    Science.gov (United States)

    Garcia-Porta, J; Litvinchuk, S N; Crochet, P A; Romano, A; Geniez, P H; Lo-Valvo, M; Lymberakis, P; Carranza, S

    2012-04-01

    In most pan-Eurasiatic species complexes, two phenomena have been traditionally considered key processes of their cladogenesis and biogeography. First, it is hypothesized that the origin and development of the Central Asian Deserts generated a biogeographic barrier that fragmented past continuous distributions in Eastern and Western domains. Second, Pleistocene glaciations have been proposed as the main process driving the regional diversification within each of these domains. The European common toad and its closest relatives provide an interesting opportunity to examine the relative contributions of these paleogeographic and paleoclimatic events to the phylogeny and biogeography of a widespread Eurasiatic group. We investigate this issue by applying a multiproxy approach combining information from molecular phylogenies, a multiple correspondence analysis of allozyme data and species distribution models. Our study includes 304 specimens from 164 populations, covering most of the distributional range of the Bufo bufo species complex in the Western Palearctic. The phylogenies (ML and Bayesian analyses) were based on a total of 1988 bp of mitochondrial DNA encompassing three genes (tRNAval, 16S and ND1). A dataset with 173 species of the family Bufonidae was assembled to estimate the separation of the two pan-Eurasiatic species complexes of Bufo and to date the main biogeographic events within the Bufo bufo species complex. The allozyme study included sixteen protein systems, corresponding to 21 presumptive loci. Finally, the distribution models were based on maximum entropy. Our distribution models show that Eastern and Western species complexes are greatly isolated by the Central Asian Deserts, and our dating estimates place this divergence during the Middle Miocene, a moment in which different sources of evidence document a major upturn of the aridification rate of Central Asia. This climate-driven process likely separated the Eastern and Western species. At the

  13. Bufo canorus Camp 1916, Yosemite Toad.

    Science.gov (United States)

    Davidson, Carlos; Fellers, Gary M.; Lannoo, Michael

    2005-01-01

    Yosemite toads (Bufo canorus) are endemic to the Sierra Nevada, California, from Ebbetts Pass, Alpine County to the Spanish Mountain area, Fresno County (Karlstrom 1962, 1973; Stebbins 1966; unpublished Sierra National Forest survey data, 1995, 2002). Sites occur from 1,950–3,444 m elevation, with the majority of sites between 2,590–3,048 m (Karlstrom, 1962). Jennings and Hayes (1994a) estimate that populations have disappeared from 50% of historically reported sites, although the overall range of the species may have only contracted in the far north and in western Fresno County. Disappearances have been concentrated at lower elevation sites on the western edge of the range, with greater persistence at higher elevation sites (Davidson et al., 2002).

  14. Sublethal effects of atrazine on embryo-larval development of Rhinella arenarum (Anura: Bufonidae).

    Science.gov (United States)

    Svartz, Gabriela V; Herkovits, Jorge; Pérez-Coll, Cristina S

    2012-05-01

    Atrazine (ATR), one of the most widely used herbicides in the world, affects not only target organisms but also the biota in general. Here, the teratogenic and neurotoxic effects of ATR on Rhinella arenarum (South American toad) embryos, and larvae were evaluated by means of standardized bioassays during acute and chronic exposures. The herbicide had a significant incidence of malformations, with a Teratogenic Index (TI) of 3.28. The main effects were delayed development, reduced body size, microcephaly, axial flexures, wavy tail and edema. In addition, delayed development, reduced development of forelimbs, and edema were recorded at metamorphosis stages. Scanning electron microscopy allowed observing different degrees of cellular dissociation and persistent cilliar cells in specific regions like the adhesive structure and tail fin. Results obtained by ATR 24 h pulse exposures at six developmental stages pointed out blastula as the most susceptible developmental stage both for immediate and delayed adverse effects. A noteworthy recovery capacity from acute toxic effects was recorded from the neural plate stage onwards. Regarding neurotoxic effects, abnormal, and erratic swimming and spasmodic contractions were recorded. Both the teratogenic and neurotoxic effects reported in this study demonstrate the importance of evaluating sublethal effects in non-target organisms as they could imply reduced fitness of individuals and eventually a population decline. The Hazard Quotients (HQ) for ATR ranged from 0.14 to 10.80, and the fact that some of these values are above USEPA's level of concern indicate that ATR is likely a risk to R. arenarum.

  15. Stage-dependent toxicity of bisphenol a on Rhinella arenarum (anura, bufonidae) embryos and larvae.

    Science.gov (United States)

    Wolkowicz, Ianina R Hutler; Herkovits, Jorge; Pérez Coll, Cristina S

    2014-02-01

    The acute and chronic toxicity of bisphenol A (BPA) was evaluated on the common South American toad Rhinella arenarum embryos and larvae by means of continuous and pulse exposure treatments. Embryos were treated continuously from early blastula (S.4) up to complete operculum (S.25), during early larval stages and by means of 24 h pulse exposures of BPA in concentrations ranging between 1.25 and 40 mg L(-1) , in order to evaluate the susceptibility to this compound in different developmental stages. For lethal effects, S.25 was the most sensitive and gastrula was the most resistant to BPA. The Teratogenic Index for neurula, the most sensitive embryonic stage for sublethal effects was 4.7. The main morphological alterations during early stages were: delayed or arrested development, reduced body size, persistent yolk plug, microcephaly, axial/tail flexures, edemas, blisters, waving fin, underdeveloped gills, mouth malformations, and cellular dissociation. BPA caused a remarkable narcotic effect from gill circulation stage (S.20) onwards in all the organisms exposed after 3 h of treatment with 10 mg L(-1) BPA. After recovering, the embryos exhibited scarce response to stimuli, erratic or circular swimming, and spasmodic contractions from 5 mg L(-1) onwards. Our results highlight the lethal and sublethal effectsof BPA on R. arenarum embryos and larvae, in the last case both at structural and functional levels. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

  16. Endosulfan acute toxicity in Bufo bufo gills: ultrastructural changes and nitric oxide synthase localization.

    Science.gov (United States)

    Bernabò, Ilaria; Brunelli, Elvira; Berg, Cecilia; Bonacci, Antonella; Tripepi, Sandro

    2008-02-18

    Endosulfan is an organochlorine pesticide used in agriculture for a wide range of crops. Endosulfan concentrations of up to 0.7 mg/L can be found in ponds and streams near sprayed agricultural fields. We investigated the short-term toxicity of endosulfan in common toad (Bufo bufo) tadpoles after 24, 48, and 96 h of exposure. Acute toxicity was evaluated at nominal concentrations ranging from 0.01 to 0.6 mg/L: concentrations that could be found after the application of pesticide. Our results show that 0.43 mg/L of endosulfan caused 50% mortality (LC(50)). The effects of a sublethal endosulfan concentration (0.2mg/L) on gill apparatus morphology were evaluated by scanning and transmission electron microscopy. Immunohistochemical methods were also applied to detect the expression pattern of the inducible isoform of nitric oxide synthase (iNOS) in the gills using the confocal laser scanner microscope. Exposure to 0.2mg/L of endosulfan caused an apparent increase in mucus production, the occurrence of secretory vesicles and lamellar bodies, a widening of intercellular spaces and additionally there was evidence of an inflammatory response in the gill apparatus. The morphological alterations occurred after 24h and were more pronounced after 48 and 96 h of exposure. Altered morphology and increased mucus secretion indicate impaired gas exchange and osmoregulation in the gills. In addition, there was an increase of iNOS expression after 24 and 48 h which may reflect hypoxia and inflammation in the gill epithelium. Our results clearly indicate that short-term exposure to a sublethal concentration of endosulfan, near the high end of the environmental range, disrupts gill morphology and function in B. bufo tadpoles.

  17. Hormonal induction of spermatozoa from amphibians with Rana temporaria and Bufo bufo as anuran models.

    Science.gov (United States)

    Uteshev, V K; Shishova, N V; Kaurova, S A; Browne, R K; Gakhova, E N

    2012-01-01

    The use of hormonally induced spermatozoa expressed in urine (HISu) is a valuable component of reproduction technologies for amphibians. Five protocols for sampling HISu from the European common frog (Rana temporaria) were compared: (1) pituitary extracts, (2) 0.12 µg g⁻¹ luteinising hormone-releasing hormone analogue (LHRHa), (3) 1.20 µg g⁻¹ LHRHa, (4) 11.7 IU g⁻¹ human chorionic gonadotrophin (hCG) and (5) 23.4 IU g⁻¹ hCG (g⁻¹ = per gram bodyweight). From 1 to 24h after administration we assessed the number and concentration of spermatozoa in spermic urine and in holding water, and in urine the percentage of motile spermatozoa and their progressive motility. The protocol using 1.20 µg g⁻¹ LHRHa gave the highest total sperm numbers (650 × 10⁶) and the highest percentage (40%) of samples with sperm concentrations above 200 × 10⁶ mL⁻¹. The percentage motility and progressive motility was similar from all protocols. Considerable amounts of spermatozoa were expressed by R. temporaria into their holding water. We tested hormonal priming and spermiation in the common toad (Bufo bufo) using 0.13 µg g⁻¹ LHRHa administered 24h before a final spermiating dose of 12.8 IU g⁻¹ hCG. No spermatozoa were expressed in holding water. Priming resulted in 35% more spermatozoa than without; however, there were no differences in sperm concentrations. Primed B. bufo produced spermatozoa with significantly higher percentage motility, but not progressive motility, membrane integrity, or abnormal spermatozoa than unprimed males.

  18. Endosulfan acute toxicity in Bufo bufo gills: Ultrastructural changes and nitric oxide synthase localization

    Energy Technology Data Exchange (ETDEWEB)

    Bernabo, Ilaria [Department of Ecology, University of Calabria, Via P. Bucci, 87036 Rende (Cosenza) (Italy); Brunelli, Elvira [Department of Ecology, University of Calabria, Via P. Bucci, 87036 Rende (Cosenza) (Italy)], E-mail: brunelli@unical.it; Berg, Cecilia [Department of Environmental Toxicology, Uppsala University, Norbyvagen 18A, 752 36 Uppsala (Sweden); Bonacci, Antonella; Tripepi, Sandro [Department of Ecology, University of Calabria, Via P. Bucci, 87036 Rende (Cosenza) (Italy)

    2008-02-18

    Endosulfan is an organochlorine pesticide used in agriculture for a wide range of crops. Endosulfan concentrations of up to 0.7 mg/L can be found in ponds and streams near sprayed agricultural fields. We investigated the short-term toxicity of endosulfan in common toad (Bufo bufo) tadpoles after 24, 48, and 96 h of exposure. Acute toxicity was evaluated at nominal concentrations ranging from 0.01 to 0.6 mg/L: concentrations that could be found after the application of pesticide. Our results show that 0.43 mg/L of endosulfan caused 50% mortality (LC{sub 50}). The effects of a sublethal endosulfan concentration (0.2 mg/L) on gill apparatus morphology were evaluated by scanning and transmission electron microscopy. Immunohistochemical methods were also applied to detect the expression pattern of the inducible isoform of nitric oxide synthase (iNOS) in the gills using the confocal laser scanner microscope. Exposure to 0.2 mg/L of endosulfan caused an apparent increase in mucus production, the occurrence of secretory vesicles and lamellar bodies, a widening of intercellular spaces and additionally there was evidence of an inflammatory response in the gill apparatus. The morphological alterations occurred after 24 h and were more pronounced after 48 and 96 h of exposure. Altered morphology and increased mucus secretion indicate impaired gas exchange and osmoregulation in the gills. In addition, there was an increase of iNOS expression after 24 and 48 h which may reflect hypoxia and inflammation in the gill epithelium. Our results clearly indicate that short-term exposure to a sublethal concentration of endosulfan, near the high end of the environmental range, disrupts gill morphology and function in B. bufo tadpoles.

  19. Serum and hepatic vitamin A levels in captive and wild marine toads (Bufo marinus).

    Science.gov (United States)

    Berkvens, Charlene N; Lentini, Andrew; Dutton, Christopher J; Pearl, David L; Barker, Ian K; Crawshaw, Graham J

    2014-01-01

    The captive breeding program for the endangered Puerto Rican crested toad (Peltophryne [Bufo] lemur) has been hampered by an undiagnosed condition called "Brown Skin Disease" (BSD). Toads develop widespread skin darkening, skin thickening and abnormal shedding and eventually succumb to a chronic loss of viability. This project evaluated the marine toad (Bufo marinus) as a model for the PRCT, examining vitamin A deficiency as a potential cause of BSD. Wild caught marine toads had significantly higher liver vitamin A concentrations (61.89 ± 63.49 µg/g) than captive born marine toads (0.58 ± 0.59 µg/g); P<0.001). A significant difference in serum vitamin A concentration was found between the captive and wild caught toads (P=0.013) and between the low vitamin A-fed and wild caught toads (P=0.004), when controlling for liver vitamin A concentrations. After captive toads were treated with topical and/or oral vitamin A, their hepatic vitamin A concentrations were similar to those of the wild toads, averaging 48.41 ± 37.03 µg/g. However, plasma vitamin A concentrations pre- and post-vitamin A supplementation did not differ statistically. We concluded that plasma vitamin A concentrations do not provide a linear indication of liver/body vitamin A status, and that both topical and oral supplementation with an oil-based vitamin A formulation can increase liver stores in amphibians. No evidence of BSD or other signs of deficiency were noted in the marine toads, although this feeding trial was relatively short (127 days). To date, clinical, pathological and research findings do not support vitamin A deficiency as a primary factor underlying BSD. © 2014 Wiley Periodicals, Inc.

  20. Thermal parameters changes in males of Rhinella arenarum (Anura:Bufonidae related to reproductive periods

    Directory of Open Access Journals (Sweden)

    Eduardo Alfredo Sanabria

    2011-03-01

    Full Text Available The regulation of body temperature in ectotherms has a major impact in their physiological and behavioral processes. Observing changes in thermal parameters related with reproduction allows us to better understand how Rhinella arenarum optimizes a thermal resource. The aim of this study was to compare the thermal parameters of this species between breeding and non-breeding periods. In the field, we recorded the body temperature from captured animals, the air temperature, and the temperature of the substrate. In the laboratory, we measured the temperature R. arenarum selected on a thermal gradient and the critical extreme temperatures. The results of our study show variations in thermal parameters between the two situations studied. This species makes efficient use of thermal resources during the breeding period by basking to significantly increase body temperature. Because calling is energetically costly for males, this behavior results in increased efficiency to callers during the breeding period. Rev. Biol. Trop. 59 (1: 347-353. Epub 2011 March 01.La regulación de la temperatura en ectotérmos tiene gran importancia en los procesos fisiológicos y comportamentales. Los cambios en los parámetros térmicos relacionados con la reproducción nos permiten entender de qué manera Rhinella arenarum optimiza el recurso térmico. El objetivo del presente trabajo fue comparar los parámetros térmicos de la especie entre el periodo reproductivo y no reproductivo. En el campo se registraron la temperatura corporal de los animales capturados, la temperatura del aire y del sustrato. Además, en laboratorio se registro la temperatura selecta en un gradiente térmico. Como así también las temperaturas criticas máxima y mínima. Los resultados de nuestro estudio muestran variaciones de los parámetros térmicos entre ambas situaciones estudiadas. Aparentemente esta especie hace un uso eficiente del recurso térmico durante el periodo reproductivo ya que

  1. Proliferative events and apoptotic remodelling in retinal development of common toad (Bufo bufo).

    Science.gov (United States)

    Pinelli, Claudia; Sansone, Alfredo; De Maio, Anna; Morgillo, Antonietta; Scandurra, Anna; D'Aniello, Biagio

    2016-01-01

    Proliferation and apoptosis are fundamental processes in the development of the retina, and a proper balance of the two phenomena is crucial to correct development of the organ. Despite intense investigation in different vertebrates, only a few studies have analyzed the cell death and the cell division quantitatively in the same species during development. Here we studied the time course of apoptosis and proliferation in the retina of common toad, Bufo bufo, and discuss the findings in an evolutionary perspective. We found cells that were dividing first scattered throughout the retina, then, in later stages, proliferation was confined to the ciliary marginal zone. This pattern was confirmed by the expression of the proliferative marker PCNA. Both proliferation and apoptosis occurred in successive waves, and two apoptotic peaks were detected: one at premetamorphosis 1 and the second at prometamorphosis. PARP-1, a known molecular marker of apoptosis, was used to confirm the data obtained by counting pyknotic nuclei. In summary, proliferative and apoptotic waves display an inverse time-relationship through development, with apoptotic peaks coinciding with low proliferation phases. In a comparative perspective, amphibians follow a developmental pattern similar to other vertebrates, although with different timing. © 2015 Wiley Periodicals, Inc.

  2. [Influence of the Concentration of Dissolved Oxygen on Embryonic Development of the Common Toad (Bufo bufo)].

    Science.gov (United States)

    Dmitrieva, E V

    2015-01-01

    Several series of experiments investigating the influence of dissolved oxygen concentrations on the growth rates and mortality in the embryogenesis of the common toad Bufo bufo were carried out. The experiments showed that, when the eggs develop singly, the lack of oxygen does not lead to an increase in mortality by the time of hatching and results only in a change in the dynamics of mortality: mortality occurs at an earlier stage of development than in the conditions of normal access to oxygen. Taking into account the combined effect of the density of eggs and the dissolved oxygen concentration, we increase the accuracy of analysis of the experimental results and improve the interpretation of the results. In the conditions of different initial density of eggs, the impact of the concentration of dissolved oxygen on mortality and rates of development of the common toad embryos is manifested in different ways. At high density, only a small percentage of embryos survives by the time of hatching, and the embryos are significantly behind in their development compared with the individuals that developed in normal oxygen conditions. The lack of oxygen dissolved in the water slows down the development of embryos of the common toad.

  3. Morphology of Bufo ictericus integument (Amphibia, Bufonidae).

    Science.gov (United States)

    de Brito-Gitirana, L; Azevedo, R A

    2005-01-01

    Bufo ictericus integument was investigated by stereoscopic, low vacuum scanning electron microscopy, transmission electron microscopy and light microscopy. The studies revealed, that the dorsal integument surface is rougher than ventral. Three types of projections are visualized: larger rounded verrucae, smaller conical cornified tubercles, and conical short spines. Prominent verrucae are observed on the dorsal surface, being flatter on the ventral surface. The tubercles are visualized only on the dorsal surface. The verrucae are separated by grooves that may contribute spreading and retention of the glandular secretion upon the integument. The pattern of the epidermal grooves is also important for water distribution, protecting the animal against desiccation. The epidermis is composed of a stratified epithelium with intraepithelial blood vessels, where keratinocytes predominate, but flask cells, and Merkel cells also occur. In the spongious dermis, cutaneous glands are visualized. The compact dermis is a series of alternating layers of bundles of collagenous fibers, and between spongious and compact dermis there are basophilic areas that correspond to Eberth-Katschenko layer. The dorsal and the ventral surfaces of B. ictericus are morphologically distinct. The integument structure is related to the physiology of each surface and represents an adaptation to habitat, reflecting a lifestyle of the animal.

  4. The complete mitochondrial genome of the Bufo stejnegeri (Anura: Bufonidae).

    Science.gov (United States)

    Dong, Bingjun; Yang, Baotian

    2016-07-01

    The complete mitochondrial genome of Bufo stejnegeri was determined, which was 17 939 bp in length. It consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and one displacement loop (D-loop). The total length of D-loop region is 2533 bp, some tandem repeat units were found in this region. The phylogenetic trees of the 20 species from anura were reconstructed based on complete mtDNA sequences by Bayesian inference and maximum likelihood analyses. The result demonstrated that B. stejnegeri is the most closely related species with other Bufo species.

  5. Cinobufacini, an aqueous extract from Bufo bufo gargarizans Cantor, induces apoptosis through a mitochondria-mediated pathway in human hepatocellular carcinoma cells.

    Science.gov (United States)

    Qi, Fanghua; Li, Anyuan; Zhao, Lin; Xu, Huanli; Inagaki, Yoshinori; Wang, Dongliang; Cui, Xiaoyan; Gao, Bo; Kokudo, Norihiro; Nakata, Munehiro; Tang, Wei

    2010-04-21

    Cinobufacini (Huachansu), an aqueous extract from the skin and parotid venom glands of Bufo bufo gargarizans Cantor, is a traditional Chinese medicine widely used in clinical cancer therapy in China. The present study sought to investigate the possible signaling pathway implicated in cinobufacini-induced apoptosis in the hepatocellular carcinoma cell lines HepG(2) and Bel-7402. The effects of cinobufacini on cell proliferation of HepG(2) and Bel-7402 cells were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assays. Cell apoptosis was detected by Hoechst 33258 staining and flow cytometry analysis. The mitochondrial membrane potential (Deltapsim) and caspase-9 and -3 activity were detected using MitoCapture reagent staining and colorimetric assays, respectively. The expression of apoptosis-related proteins and release of cytochrome c were assessed by Western blot analysis. Cinobufacini significantly inhibited cell proliferation of both cell lines in a dose- and time-dependent manner. Marked changes in apoptotic morphology and apoptosis rates were clearly observed after cinobufacini treatment. The protein expression of Bax increased whereas that of Bcl-2 decreased, leading to an increase in the Bax/Bcl-2 ratio. Subsequently, cinobufacini disrupted the mitochondrial membrane potential (Deltapsim) and resulted in the release of cytochrome c, activation of both caspase-9 and -3, and cleavage of poly (ADP-ribose) polymerase (PARP). The present study indicated that cinobufacini can induce apoptosis of HepG(2) and Bel-7402 cells through a mitochondria-mediated apoptosis pathway. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  6. Morphological differentiation of the common toad Bufo bufo (Linnaeus, 1758 in the central part of the Balkan Peninsula

    Directory of Open Access Journals (Sweden)

    Čađenović Natalija

    2013-01-01

    Full Text Available This study analyzes the degree of morphological differentiation among populations of the common toad Bufo bufo in the central part of the Balkan Peninsula. Variations in a number of morphometric and qualitative characters in 14 population samples were analyzed using univariate and multivariate statistics. We found a high degree of female-biased sexual size dimorphism. Morphological variation among the samples was more expressed in morphometric than in qualitative characters. The significant size differences that exist between northern and southern population groups could be the result of phenotypic plasticity. Our results do not support a clear split between northern and southern populations, contrary to the current taxonomic treatment of these groups as B. b. bufo and B. b. spinosus, respectively. [Projekat Ministarstva nauke Republike Srbije, br. 173043

  7. Slope-Based and Geometric Encoding of a Goal Location by the Terrestrial Toad (Rhinella arenarum).

    Science.gov (United States)

    Sotelo, María Inés; Bingman, Verner P; Muzio, Rubén N

    2017-08-28

    The current study was designed to test for the ability of terrestrial toads, Rhinella arenarum, to use slope as source of spatial information to locate a goal, and investigate the relative importance of slope and geometric information for goal localization. Toads were trained to locate a single, water-reward goal location in a corner of a rectangular arena placed on an incline. Once the toads learned the task, 3 types of probe trials were carried out to determine the relative use of slope and geometric information for goal localization. The probe trials revealed that the toads were able to independently use slope, and as previously reported, geometry to locate the goal. However, the boundary geometry of the experimental arena was found to be preferentially used by the toads when geometric and slope information were set in conflict. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  8. N-methyl serotonin analogues from the Bufo bufo toad venom interact efficiently with the α7 nicotinic acetylcholine receptors.

    Science.gov (United States)

    Kryukova, E V; Lebedev, D S; Ivanov, I A; Ivanov, D A; Starkov, V G; Tsetlin, V I; Utkin, Yu N

    2017-01-01

    Two low-molecular-weight compounds were isolated from the parotid gland secret of the toad Bufo bufo, which by absorption spectra and HPLC-MS/MS chromatography data correspond to di- and trimethyl derivatives of serotonin (5-hydorxytryptamine): bufotenine (confirmed by counter synthesis) and bufotenidine (5-HTQ). In experiments on competitive radioligand binding, these compounds showed a higher affinity and selectivity for neuronal α7 nicotinic acetylcholine receptors compared with the muscular cholinergic receptors. The most efficient compound in terms of binding value was bufotenine, the efficiency of 5-HTQ was an order of magnitude lower, and the minimal activity was exhibited by serotonin.

  9. Effects of salinity stress on Bufo balearicus and Bufo bufo tadpoles: Tolerance, morphological gill alterations and Na(+)/K(+)-ATPase localization.

    Science.gov (United States)

    Bernabò, Ilaria; Bonacci, Antonella; Coscarelli, Francesca; Tripepi, Manuela; Brunelli, Elvira

    2013-05-15

    Freshwater habitats are globally threatened by human-induced secondary salinization. Amphibians are generally poorly adapted to survive in saline environments. We experimentally investigated the effects of chronic exposure to various salinities (5%, 10%, 15%, 20%, 25%, 30% and 35% seawater, SW) on survival, larval growth and metamorphosis of tadpoles from two amphibian populations belonging to two species: the green toad Bufo balearicus and the common toad Bufo bufo. In addition, gill morphology of tadpoles of both species after acute exposure to hypertonic conditions (20%, 25%, and 30% SW) was examined by light and electron microscopy. Tadpoles experienced 100% mortality above 20% SW in B. balearicus while above 15% SW in B. bufo. We detected also sublethal effects of salinity stress on growth and metamorphosis. B. bufo cannot withstand chronic exposure to salinity above 5% SW, tadpoles grew slower and were significantly smaller than those in control at metamorphosis. B. balearicus tolerated salinity up to 20% SW without apparent effects during larval development, but starting from 15% SW tadpoles metamorphosed later and at a smaller size compared with control. We also revealed a negative relation between increasing salt concentration and gill integrity. The main modifications were increased mucous secretion, detachment of external layer, alteration of epithelial surface, degeneration phenomena, appearance of residual bodies, and macrophage immigration. These morphological alterations of gill epithelium can interfere with respiratory function and both osmotic and acid-base regulation. Significant variations in branchial Na(+)/K(+)-ATPase activity were also observed between two species; moreover an increase in enzyme activity was evident in response to SW exposure. Epithelial responses to increasing salt concentration were different in the populations belonging to two species: the intensity of histological and ultrastructural pathology in B. bufo was greater and we

  10. Effects of salinity stress on Bufo balearicus and Bufo bufo tadpoles: Tolerance, morphological gill alterations and Na{sup +}/K{sup +}-ATPase localization

    Energy Technology Data Exchange (ETDEWEB)

    Bernabò, Ilaria; Bonacci, Antonella; Coscarelli, Francesca [Department of Ecology, University of Calabria, Via P. Bucci, 87036 Rende (Cosenza) (Italy); Tripepi, Manuela [University of Pennsylvania, Department of Biology, 201 Leidy Laboratories, Philadelphia, PA 19104 (United States); Brunelli, Elvira, E-mail: brunelli@unical.it [Department of Ecology, University of Calabria, Via P. Bucci, 87036 Rende (Cosenza) (Italy)

    2013-05-15

    Freshwater habitats are globally threatened by human-induced secondary salinization. Amphibians are generally poorly adapted to survive in saline environments. We experimentally investigated the effects of chronic exposure to various salinities (5%, 10%, 15%, 20%, 25%, 30% and 35% seawater, SW) on survival, larval growth and metamorphosis of tadpoles from two amphibian populations belonging to two species: the green toad Bufo balearicus and the common toad Bufo bufo. In addition, gill morphology of tadpoles of both species after acute exposure to hypertonic conditions (20%, 25%, and 30% SW) was examined by light and electron microscopy. Tadpoles experienced 100% mortality above 20% SW in B. balearicus while above 15% SW in B. bufo. We detected also sublethal effects of salinity stress on growth and metamorphosis. B. bufo cannot withstand chronic exposure to salinity above 5% SW, tadpoles grew slower and were significantly smaller than those in control at metamorphosis. B. balearicus tolerated salinity up to 20% SW without apparent effects during larval development, but starting from 15% SW tadpoles metamorphosed later and at a smaller size compared with control. We also revealed a negative relation between increasing salt concentration and gill integrity. The main modifications were increased mucous secretion, detachment of external layer, alteration of epithelial surface, degeneration phenomena, appearance of residual bodies, and macrophage immigration. These morphological alterations of gill epithelium can interfere with respiratory function and both osmotic and acid-base regulation. Significant variations in branchial Na{sup +}/K{sup +}-ATPase activity were also observed between two species; moreover an increase in enzyme activity was evident in response to SW exposure. Epithelial responses to increasing salt concentration were different in the populations belonging to two species: the intensity of histological and ultrastructural pathology in B. bufo was

  11. Breeding frequency of western toads (Bufo boreas) in northeastern Oregeon

    Science.gov (United States)

    Evelyn L. Bull; Cynthia Carey

    2008-01-01

    Many species of toads (family Bufonidae), including the western toad (Bufo boreas), are declining in-the western United States. The ability of this species to recover from declines depends, in part, on its reproductive success. This study examined the breeding frequency in both sexes of B. borelis in northeastern Oregon compared to...

  12. Evolution of Acoustic Behaviour in African Bufo (Anura: Bufonidae ...

    African Journals Online (AJOL)

    Mating calls are known for 29 species of African Bufo belonging to 11 species groups. Twenty-five African species, representing eight species groups (including four groups or complexes having 2N=22) have calls which Martin (1972) termed Type I. This call type is also found in Schismaderma carens, Nectophrynoides ...

  13. (Ciliophora: Peritrichia) from the urinary bladder of Bufo gutturalis ...

    African Journals Online (AJOL)

    1988-09-07

    Sep 7, 1988 ... described trichodinids from amphibians in southern. Africa, i.e. Trichodina xenopodos Fantham, 1924 from the urinary bladder of the African clawed toad, Xenopus laevis and T. bufonis Fantham, 1924 from Bufo regularis. Although both these descriptions did not make use of silver-impregnation and the ...

  14. Arginine derivatives of dicarboxylic acids from the parotid gland secretions of common toad Bufo bufo-New agonists of ionotropic γ-aminobutyric acid receptors.

    Science.gov (United States)

    Lebedev, D S; Ivanov, I A; Kryukova, E V; Starkov, V G; Tsetlin, V I; Utkin, Yu N

    2017-05-01

    Compounds activating γ-aminobutyric acid type A receptor were isolated from the toad Bufo bufo venom as a result of chromatographic separation. Analysis of the structure of these compounds by mass spectrometry and nuclear magnetic resonance showed that they are arginine derivatives of dicarboxylic acids and represent suberylarginine, pimeloylarginine, and adipoylarginine.

  15. Phenotypic divergence of the common toad (Bufo bufo) along an altitudinal gradient: evidence for local adaptation.

    Science.gov (United States)

    Luquet, E; Léna, J-P; Miaud, C; Plénet, S

    2015-01-01

    Variation in the environment can induce different patterns of genetic and phenotypic differentiation among populations. Both neutral processes and selection can influence phenotypic differentiation. Altitudinal phenotypic variation is of particular interest in disentangling the interplay between neutral processes and selection in the dynamics of local adaptation processes but remains little explored. We conducted a common garden experiment to study the phenotypic divergence in larval life-history traits among nine populations of the common toad (Bufo bufo) along an altitudinal gradient in France. We further used correlation among population pairwise estimates of quantitative trait (QST) and neutral genetic divergence (FST from neutral microsatellite markers), as well as altitudinal difference, to estimate the relative role of divergent selection and neutral genetic processes in phenotypic divergence. We provided evidence for a neutral genetic differentiation resulting from both isolation by distance and difference in altitude. We found evidence for phenotypic divergence along the altitudinal gradient (faster development, lower growth rate and smaller metamorphic size). The correlation between pairwise QSTs-FSTs and altitude differences suggested that this phenotypic differentiation was most likely driven by altitude-mediated selection rather than by neutral genetic processes. Moreover, we found different divergence patterns for larval traits, suggesting that different selective agents may act on these traits and/or selection on one trait may constrain the evolution on another through genetic correlation. Our study highlighted the need to design more integrative studies on the common toad to unravel the underlying processes of phenotypic divergence and its selective agents in the context of environmental clines.

  16. DC electrical stimulation of the pretectal thalamus and its effects on the feeding behavior of the toad (Bufo bufo).

    Science.gov (United States)

    McConville, James; Laming, Peter R

    2007-06-01

    The feeding motivation of the common European common toad (Bufo bufo) can be quantified by the feeding sequence of arousal-orientation-approach-fixate-snap. Previous work has found that the optic tectum is an important structure responsible for the mediation of feeding behaviors, and combined electrical and visual stimulation of the optic tectum was found to increase the animals feeding behaviors. However, the pretectal thalamus has an inhibitory influence upon the optic tectum and its lesion results in disinhibited feeding behaviors. This suggests that feeding behavior of anurans is also subject to influence from the pretectal thalamus. Previous studies involving the application of DC stimulation to brain tissue has generated slow potential shifts and these shifts have been implicated in the modulation of the neural mechanisms associated with behavior. The current study investigated the application of DC stimulation to the diencephalon surface dorsal to the lateral posterodorsal pretectal thalamic nucleus in Bufo bufo, in order to assess effects on feeding motivation. The application of DC stimulation increased the incidence of avoidance behaviors to a visual prey stimulus while reducing the prey catching behavior component of approach, suggesting that the DC current applied to the pretectum increased the inhibition upon the feeding elements of the optic tectum. This can be explained by the generation of slow potential shifts.

  17. Immunolocation of mitochondria-rich cells in epidermis of the common toad, Bufo bufo L

    DEFF Research Database (Denmark)

    Spies, Ingrid B.M.

    1997-01-01

    Adult toads, skin, flask-shaped cells, cytoskeleton, keratin expression, immunohistochemistry, differentiation.......Adult toads, skin, flask-shaped cells, cytoskeleton, keratin expression, immunohistochemistry, differentiation....

  18. Bufo alvarius: a potent hallucinogen of animal origin.

    Science.gov (United States)

    Weil, A T; Davis, W

    1994-01-01

    Anthropologists have long speculated that ancient peoples of Mesoameria used a toad, Bufo marinus, as a ritual intoxicant. This hypothesis rests on many iconographic and mythological representations of toads and on a number of speculative ethnographic reports. The authors reject B. marinus as a candidate for such use because of the toxicity of its venom. A more likely candidate is the Sonoran desert toad, Bufo alvarius, which secretes large amounts of the potent known hallucinogen, 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT). The authors demonstrate that the venom of B. alvarius, although known to be toxic when consumed orally, may be safely smoked and is powerfully psychoactive by that route of administration. These experiments are the first documentation of an hallucinogenic agent from the animal kingdom, and they provide clear evidence of a psychoactive toad that could have been employed by Precolumbian peoples of the New World.

  19. Article Syndactyly in Bufo maculatus Hallowell (Amphibia: Anura ...

    African Journals Online (AJOL)

    Syndactyly in five specimens of Bufo maculatus, all from a small area 25 km west of Harare, Zimbabwe, is described. In three cases only one pair of digits was involved (two of the hand, one of the foot); in a fourth, two pairs of digits on one foot were involved; and in the fifth case, all digits of one hand were involved together ...

  20. Flurochloridone-based herbicides induced genotoxicity effects on Rhinella arenarum tadpoles (Anura: Bufonidae).

    Science.gov (United States)

    Nikoloff, Noelia; Natale, Guillermo S; Marino, Damián; Soloneski, Sonia; Larramendy, Marcelo L

    2014-02-01

    Acute toxicity and genotoxicity of the flurochloridone (FLC)-containing commercial formulation herbicides Twin Pack Gold(®) (25 percent a.i.) and Rainbow(®) (25 percent a.i.) were evaluated on Rhinella arenarum (Anura: Bufonidae) tadpoles exposed under laboratory conditions. Lethal effect was evaluated as end point for lethality, whereas frequency of micronuclei (MN) and single cell gel electrophoresis (SCGE) were employed as end points for genotoxicity. Lethality studies revealed equivalent LC-5096 h values of 2.96 and 2.85 mg/L for Twin Pack Gold(®) and Rainbow(®), respectively. Twin Pack Gold(®) did not induce DNA damage at the chromosomal level, whereas Rainbow(®) increased the frequency of MN only when the lowest concentration (0.71 mg/L) was used. However, all concentrations of Twin Pack Gold(®) and Rainbow(®) increased the frequencies of primary DNA lesions estimated by alkaline SCGE. This study represents the first evidence of the acute toxic and genotoxic effects exerted by two FLC-based commercial formulations, Twin Pack Gold(®) and Rainbow(®), on tadpoles of an amphibian species native to Argentina under laboratory conditions. Finally, our findings highlight the importance of minimizing the impacts on nontarget living species exposed to agrochemicals. © 2013 Elsevier Inc. All rights reserved.

  1. Water-balance response of Rhinella arenarum (Hensel, 1867 tadpoles to graduated increase in environmental osmolarity

    Directory of Open Access Journals (Sweden)

    L. Ferrari

    Full Text Available The water balance and the upper limit of osmotic tolerance of premetamorphic Rhinella arenarum larvae (Gosner's stage 26 was evaluated after semistatic incubation in electrolyte (NaCl and non-electrolyte (mannitol media following a protocol of progressively increased osmotic pressure. Wet and dry weights were measured to calculate the water content as a derived variable indicative of the hydric balance. Statistical analysis was performed using univariate and integrated multivariate analysis. Tadpoles survived in electrolyte and non-electrolyte solutions up to 200 mOsm. The discriminant function was the best tool to describe the responses of the animals to external environmental stress under experimental conditions. The results were compared with those obtained in previous studies using a protocol of acute exposure to the same media used in this study. It was concluded that a multivariate analysis is an appropriate approach to describe the responses of tadpoles to changes in the environmental physicochemical parameters, and b progressive and acute acclimation to the experimental solutions induced similar responses.

  2. Goal orientation by geometric and feature cues: spatial learning in the terrestrial toad Rhinella arenarum.

    Science.gov (United States)

    Sotelo, María Inés; Bingman, Verner Peter; Muzio, Rubén N

    2015-01-01

    Although of crucial importance in vertebrate evolution, amphibians are rarely considered in studies of comparative cognition. Using water as reward, we studied whether the terrestrial toad, Rhinella arenarum, is also capable of encoding geometric and feature information to navigate to a goal location. Experimental toads, partially dehydrated, were trained in either a white rectangular box (Geometry-only, Experiment 1) or in the same box with a removable colored panel (Geometry-Feature, Experiment 2) covering one wall. Four water containers were used, but only one (Geometry-Feature), or two in geometrically equivalent corners (Geometry-only), had water accessible to the trained animals. After learning to successfully locate the water reward, probe trials were carried out by changing the shape of the arena or the location of the feature cue. Probe tests revealed that, under the experimental conditions used, toads can use both geometry and feature to locate a goal location, but geometry is more potent as a navigational cue. The results generally agree with findings from other vertebrates and support the idea that at the behavioral-level geometric orientation is a conserved feature shared by all vertebrates.

  3. Apoptosis, proliferation and presence of estradiol receptors in the testes and Bidder's organ of the toad Rhinella arenarum (Amphibia, Anura).

    Science.gov (United States)

    Scaia, María Florencia; Czuchlej, Silvia Cristina; Cervino, Nadia; Ceballos, Nora Raquel

    2016-04-01

    The dynamic equilibrium between spermatogonial proliferation and testicular apoptosis determines the progression of spermatogenesis in amphibians. Estrogens and their receptors play a central role in regulating spermatogenesis in vertebrates, and in some species of anurans, estradiol (E2 ) is involved in the regulation of spermatogonial proliferation and apoptosis of germ cells. Bidder's organ (BO) is a structure characteristic of Bufonidae that has historically been compared to an undeveloped ovary. In adult Rhinella arenarum males, BO is one of the main sources of plasma E2 . The aim of this study was 1) to describe the seasonal variations in testicular apoptosis, spermatogonial proliferation, and cellular proliferation in BO; and 2) to analyze the presence and localization of estrogen receptor β (ERβ) in the testes and BO of R. arenarum. Testicular fragments and BOs from animals collected during the year were labeled with 5-bromo-2'-deoxyuridine (BrdU) and BrdU incorporation was determined using immunohistochemistry. Apoptosis in testicular sections was detected using the TUNEL method, and ERβ localization was assessed using immunohistochemistry in testes and BOs. The results indicate that spermatogonial proliferation is highest during the reproductive season and that cysts of spermatocytes and spermatids undergo apoptosis during the postreproductive season. Furthermore, the proliferation of follicular cells is highest during the reproductive and postreproductive seasons. ERβ was primarily detected by immunolocalization in Sertoli cells, follicular cells, and oocytes. Taken together, these results suggest that cysts that do not form spermatozoa are removed from testes by apoptosis and that estrogens regulate both spermatogenesis and oogenesis in adult males of R. arenarum. © 2015 Wiley Periodicals, Inc.

  4. Report of Bufo tihamicus karyotype from Saudi Arabia | Al-Shehri ...

    African Journals Online (AJOL)

    This study gives a description of the Karyotype of the Tihama toad Bufo tihamicus from Saudi Arabia. Samples of males and females of Bufo tihamicus Parker were collected from Gazan Province of Kingdom of Saudi Arabia. The karyotype consists of a diploid number 2n = 22 and the fundamental number NF = 44 in both of ...

  5. Morphological and genetic differentiation of Bufo toads: two cryptic species in Western Europe (Anura, Bufonidae)

    NARCIS (Netherlands)

    Arntzen, J.W.; McAtear, J.; Recuero, E.; Ziermann, J.M.; Ohler, A.; Alphen, van J.; Martínez-Solano, I.

    2013-01-01

    The Common toad Bufo bufo sensu lato is a widespread, morphologically conserved taxon. Recent studies have uncovered deep genetic differentiation between population groups, highlighting the need to revise the current taxonomy of the group and recognize additional species. Here we investigate

  6. Comparative cytogenetic studies of Bufo ictericus, B. paracnemis (Amphibia, Anura and an intermediate form in sympatry

    Directory of Open Access Journals (Sweden)

    Azevedo MFC

    2003-01-01

    Full Text Available Specimens of Bufo ictericus, Bufo paracnemis and a third type, considered an intermediate subgroup between these species, were cytogenetically studied by conventional Giemsa staining, C-banding and staining of the nucleolus organizer region (NOR. The nuclear DNA content and seroproteins were also analyzed to characterize these species, and verify the possibility of hybridization between them. Karyotypes and cytogenetic markers were essentially equal on the basis of the methods used. The DNA nuclear content found was 6.25 ± 0.30 pg/DNA in Bufo ictericus; 7.57 ± 0.40 pg/DNA in Bufo paracnemis and 7.04 ± 0.29 pg/DNA in the intermediate subgroup. Eletrophoresis of total blood serum in Bufo ictericus, Bufo paracnemis and the intermediate specimens revealed a remarkable difference in the patterns of the protein bands whose molecular weight corresponded to that of albumin. While the parental species presented two different bands, the intermediate form presented 4. However, only three of these bands were seen in each specimen. The results obtained pointed to a high probability for natural hybridization between Bufo ictericus and Bufo paracnemis in the site and specimens studied.

  7. A contribution to the knowledge of the trophic spectrum of the Common toad (Bufo bufo L., 1758 (Amphibia: Anura from Bulgaria

    Directory of Open Access Journals (Sweden)

    Petar Boyadzhiev

    2009-07-01

    Full Text Available During our study we identified 500 prey items in 20 prey categories in the trophic spectrum of Bufo bufo with average number of prey items per stomach 25.00. The most important prey taxon is Formicidae (70.20%, followed by Coleoptera (especially Carabidae – 11.40%, as well as non-insect invertebrates (Isopoda, Gastropoda, Arachnida which also play significant role. The estimated trophic niche breadth is low – 1.96.

  8. Vasculature of the parotoid glands of four species of toads (bufonidae: bufo).

    Science.gov (United States)

    Hutchinson, Deborah A; Savitzky, Alan H

    2004-05-01

    The parotoid glands of toads (Bufonidae) consist of large aggregations of granular glands located between the otic region of the skull and the scapular region. To determine the circulatory pattern of these glands, we perfused the vascular systems of Bufo alvarius, B. marinus, B. terrestris, and B. valliceps with either India ink or Microfil, a fine latex. The perfused glands were studied by gross dissection, microscopic examination, and histology. The vascular patterns of the parotoid glands were compared to the arrangement of vessels in the dorsal skin of Rana sphenocephala (Ranidae), a frog that lacks parotoid glands. The parotoid glands of the four species of toads are supplied with blood by the lateral and dorsal cutaneous arteries and are drained by one or more branches of the internal jugular vein. The dorsal cutaneous artery supplies most of the blood to the parotoid glands in B. terrestris and B. valliceps. In B. alvarius and B. marinus, both the lateral and dorsal cutaneous arteries serve major roles in the blood supply of the glands. These patterns of blood flow have not been described previously for parotoid glands and conflict with earlier accounts for B. alvarius and B. marinus. The arteries and veins associated with the parotoid glands of toads are present in R. sphenocephala, but are arranged differently. In R. sphenocephala, the lateral cutaneous artery supplies the dorsal and lateral skin posterior to the shoulder region, whereas the dorsal cutaneous artery supplies the skin of the shoulder region. In toads, both the lateral and dorsal cutaneous arteries supply the skin of the shoulder region and ramify into subcutaneous capillaries that surround the secretory units of the parotoid glands. Extensive vasculature presumably is important for delivering cholesterol and other precursor molecules to the parotoid glands, where those compounds are converted into toxins. Copyright 2004 Wiley-Liss, Inc.

  9. Factors limiting the recovery of boreal toads (Bufo b. boreas)

    Science.gov (United States)

    Carey, C.; Corn, P.S.; Jones, M.S.; Livo, L.J.; Muths, E.; Loeffler, C.W.; Lannoo, M.

    2005-01-01

    Boreal toads (Bufo b. boreas) are widely distributed over much of the mountainous western United States. Populations in the Southern Rocky Mountains suffered extensive declines in the late 1970s through early 1980s (Carey, 1993). At the time, these mass mortalities were thought to be associated with a bacterial infection (Carey, 1993). Although the few populations that survived the mass die-offs were not systematically monitored until at least 1993, no mass mortalities had been observed until 1996 when die-offs were observed. A mycotic skin infection associated with a chytrid fungus is now causing mortality of toads in at least two of the populations (M.S. Jones and D.E. Green, unpublished data; Muths et al., 2003). Boreal toads are now absent throughout large areas of their former distribution in Colorado and southern Wyoming and may be extinct in New Mexico (Corn et al., 1989; Carey, 1993; Stuart and Painter, 1994). These toads are classified as “endangered” by Colorado and New Mexico and are designated as a protected non-game species in Wyoming. The U.S. Fish and Wildlife Service has categorized the Southern Rocky Mountain populations for federal listing and is currently reviewing their designation as a “warranted but precluded” species for possible listing in the next few years. For the management of boreal toads and their habitats, a Boreal Toad Recovery Team was formed by the Colorado Division of Wildlife in 1995 as part of a collaborative effort with federal agencies within the United States’ departments of the Interior and Agriculture and with agencies in two adjoining states. To date, conservation agreements have been signed by eight state and federal agencies and by the Colorado Natural Heritage Program. Although boreal toads were considered common throughout their range in Colorado, no comprehensive surveys of the numbers and sizes of their populations were conducted prior to mass die-offs in the 1970s. Surveys completed in the late 1980s to

  10. Effect of different types of sesquiterpene lactones on the maturation of Rhinella arenarum oocytes.

    Science.gov (United States)

    Sánchez-Toranzo, G; Zapata-Martínez, J; Catalán, C; Bühler, M I

    2015-06-01

    The sesquiterpene lactones (STLs) are a large class of plant secondary metabolites that are generally found in the Asteraceae family and that have high diversity with respect to chemical structure as well as biological activity. STLs have been classified into different groups, such as guaianolides, germacranolides, and melampolides etc., based on their carboxylic skeleton. In amphibians, fully grown ovarian oocytes are arrested at the beginning of meiosis I. Under the stimulus of progesterone, this meiotic arrest is released and meiosis progresses to metaphase II, a process known as oocyte maturation. The purpose of this work was to determine whether sesquiterpene lactones from the germacranolide and melampolide groups act as inhibitor agents on the meiosis of amphibian oocytes in vitro. Results for germacranolides indicated that the addition of deoxyelephantopins caused a high degree of inhibition and that minimolide showed a moderate inhibitory effect, whereas glaucolide A was inactive. Furthermore, the addition of melampolides (uvedalin, enhydrin, polymatin A and polymatin B) showed inhibitory effects. For enhydrin and uvedalin, inhibitory effects were observed at the higher concentrations assayed. The results of this study suggest that the inhibitory activity of the tested sesquiterpene lactones on the meiosis of Rhinella arenarum oocytes is not dependent on the group to which they belong, i.e. not on the carboxylic skeleton, but probably due to the arrangement and type of function groups present in the molecules. All assayed lactones in the germacranolide group showed low toxicity. In contrast, important differences in toxicity were observed for lactones from the melampolide group: enhydrin and uvedalin showed low toxicity, but polymatin A and B were highly toxic.

  11. Characterization and seasonal changes in LHβ and FSHβ mRNA of Rhinella arenarum (Amphibia, Anura).

    Science.gov (United States)

    Volonteri, M Clara; Regueira, Eleonora; Scaia, M Florencia; Ceballos, Nora R

    2013-06-15

    In anurans, two types of gonadotropins were described in several species of Ranidae and Pipidae families but only in one of the Bufonidae family. Rhinella arenarum is a bufonid that have the lowest concentration of plasma androgens during the breeding. The objective of this paper was to characterize the cDNA sequence of β subunit of LH and FSH from toad pituitary and study seasonal variation in gonadotropins mRNA using quantitative real-time RT-PCR. The LHβ cDNA is a 636 bp sequence containing an open reading frame (ORF), 45 bp of 5'-untranslated region (UTR) and 174 bp of 3'-UTR. The ORF encodes for a signal peptide of 26 amino acids and a mature protein of 113 amino acids with one N-glycosylation site at the 34th position. The FSHβ cDNA sequence is a 535 bp fragment containing an ORF, 8 bp of 5'-UTR and 152 bp of 3'-UTR. The ORF encodes for a signal peptide of 20 amino acids and a mature protein of 104 amino acids with two N-glycosylation sites at 25th and 42nd positions. Multiple alignments of aminoacid deduced sequences of LHβ and FSHβ (teleosts, amphibians, birds, mammals) showed that all the tetrapods studied conserve 12 cysteins and one (LH) or two (FSH) N-Glycosylation sites. LHβ is closer to teleosts than to mammals and birds while FSHβ is closer to mammals. The analysis of seasonal changes in LHβ and FSHβ mRNA indicates that transcript levels have seasonal variations and that the profile of androgens is opposite to that of the gonadotropins mRNA. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Interaction between Pax6 and its novel mutant in Bufo raddei Strauch.

    Science.gov (United States)

    Ju, Furong; Zhao, Yongqing; Zhao, Yuanlin; Wang, Ying; Wen, Fan; Ye, Lin; Gao, Lan

    2011-01-01

    Exploration of the relationship between a novel paired box 6 (Pax6) mutant and Pax6 in Bufo raddei Strauch. RT-PCR, yeast 2-hybrid system, and co-immunoprecipitation were used to analyze the Pax6 protein and its mutant during embryonic eye development in Bufo raddei Strauch. We have cloned the Pax6 ORF sequence from Bufo raddei Strauch. Here we report the cloning of a novel Pax6 homolog of Bufo raddei Strauch named Pax6 variant. Comparing the 2 genes, the homolog of ORF nucleotide sequence is more than 99% in Bufo raddei Strauch; only the proline-serine-threonine(PST)-rich transaction domain differs. The deduced amino acid sequences of PST region are 53.1% identical. An interaction was found between Pax6 and Pax6 variant via yeast 2-hybrid system; with further study, we found that they interacted in vivo via co-immunopricipitation. A Pax6 mutant was first found in Bufo raddei Strauch. Interaction between Pax6 and Pax6 variant may play a critical role during eye development in Bufo raddei Strauch. This suggests that expression of Pax6 variant may play a role and appears to be a necessity in eye development, but that Pax6 itself is still pivotal in eye development.

  13. The complete mitochondrial genome of the Bufo tibetanus (Anura: Bufonidae).

    Science.gov (United States)

    Wang, Xinbo; Wang, Yan; Yue, Bisong; Zhang, Xiuyue; Liu, Shaolong

    2013-06-01

    The total length of the Bufo tibetanus mitochondrial genome sequence is 17,405 bp. It consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and 1 displacement loop (D-loop). Except for eight tRNAs and nd6 genes, all other mitochondrial genes are encoded on the heavy strand (H strand). Most of the 22 tRNA genes can fold into a typical cloverleaf secondary structure by tRNAscan-SE, except for tRNA(Ser). Molecular data presented here provide a useful toll for helping set the stage for further studies and the molecular evolution of the mitochondrial genome.

  14. Agricultural intensity in ovo affects growth, metamorphic development and sexual differentiation in the common toad (Bufo bufo).

    Science.gov (United States)

    Orton, Frances; Routledge, Edwin

    2011-06-01

    Pollution was cited by the Global Amphibian Assessment to be the second most important cause of amphibian decline worldwide, however, the effects of the agricultural environment on amphibians are not well understood. In this study, spawn from Bufo bufo was taken from four sites in England and Wales with varying intensities of arable agriculture. Spawn was either placed in tanks containing aged tap water (ex-situ, five replicates) or in cages at the native site (caged, five replicates). Hatching success, abnormal tadpoles, and forelimb emergence were recorded during the larval stage. Individuals were also sampled at five time points (TP) during development (5-, 7-, 9-, 12-, 15-weeks post-hatch) and analysed for morphological parameters. The thyroids (TP2) and the gonads (TP3,4,5) were also analysed histologically. With the exception of the thyroid histopathology, all analysed endpoints were significantly different between ex-situ individuals reared under identical conditions from the different sites. In addition, intensity of arable agriculture had a negative effect on growth and development. At one site, despite distinct rearing conditions, a high level of intersex (up to 42%) and similar sex ratios were observed in both ex-situ and caged individuals. Taken together, these data suggest that maternal exposure and/or events in ovo had a much larger effect on growth, metamorphic development, and sexual differentiation in B. bufo than the ambient environment. This could have important implications for traditional exposure scenarios that typically begin at the larval stage. Intersex is reported for the first time in European amphibians in situ, highlighting the potential use of distinct populations of amphibians in fundamental research into the aetiology of specific developmental effects in wild amphibians.

  15. Behavioral response and kinetics of terrestrial atrazine exposure in American toads (bufo americanus)

    Science.gov (United States)

    Storrs, Mendez S.I.; Tillitt, D.E.; Rittenhouse, T.A.G.; Semlitsch, R.D.

    2009-01-01

    Amphibians in terrestrial environments obtain water through a highly vascularized pelvic patch of skin. Chemicals can also be exchanged across this patch. Atrazine (ATZ), a widespread herbicide, continues to be a concern among amphibian ecologists based on potential exposure and toxicity. Few studies have examined its impact on the terrestrial juvenile or adult stages of toads. In the current study, we asked the following questions: (1) Will juvenile American toads (Bufo americanus) avoid soils contaminated with ATZ? (2) Can they absorb ATZ across the pelvic patch? (3) If so, how is it distributed among the organs and eventually eliminated? We conducted a behavioral choice test between control soil and soil dosed with ecologically relevant concentrations of ATZ. In addition, we examined the uptake, distribution, and elimination of water dosed with 14C-labeled ATZ. Our data demonstrate that toads do not avoid ATZ-laden soils. ATZ crossed the pelvic patch rapidly and reached an apparent equilibrium within 5 h. The majority of the radiolabeled ATZ ended up in the intestines, whereas the greatest concentrations were observed in the gall bladder. Thus, exposure of adult life stages of amphibians through direct uptake of ATZ from soils and runoff water should be considered in risk evaluations. ?? 2009 Springer Science+Business Media, LLC.

  16. Molecular effectors in the chronic exposure to arsenic as early and sensitive biomarkers in developing Rhinella arenarum toads

    Energy Technology Data Exchange (ETDEWEB)

    Mardirosian, Mariana Noelia; Ceschin, Danilo Guillermo; Lascano, Cecilia Inés; Venturino, Andrés, E-mail: a.venturino@conicet.gov.ar

    2017-05-15

    Highlights: • Arsenic early induces MAPK pathway in R. arenarum embryos and larvae. • The MAPKs MEK-ERK in turn upregulate the transcription factors c-FOS and c-JUN. • SOD, CAT and GST would be affected by ROS at synthesis and degradation level. • Low As levels inducing molecular biomarkers have high probabilities of exceedence. • Molecular biomarkers are most adequate to ascertain As impact in R. arenarum. - Abstract: Arsenic, a natural element of ecological relevance, is one of the most toxic elements present in various regions of the world. It can be found in natural water sources throughout Argentina in concentrations between 0.01 and 15 mg L{sup –1}. The Argentinean autochthonous toad Rhinella arenarum was selected to study the molecular mechanisms involved in the effects and response to the chronic As exposure along its embryonic and larval development. We evaluated the effects on MAPK signal transduction pathway and transcription factors c-FOS and c-JUN, and the regulation of the expression at protein levels of different antioxidant enzymes. Our results indicated that As is modulating the MAPK pathway, increasing MEK and ERK levels both in the nuclear and post-nuclear fraction along the embryonic development and mainly at the beginning of the larval stage. Through this pathway, As can upregulate transcription factors like c-FOS and c-JUN, impacting the antioxidant response of the exposed embryos and larvae through antioxidant enzymes and recycling of GSH. Arsenic triggered specifically the synthesis of antioxidant enzymes in exposed R. arenarum embryo and larvae. In particular, the expression levels of SOD, CAT and GST enzymes analyzed by Western blot showed a similar behavior to their enzymatic activities in our previous work. This fact suggests that not only the synthesis of these antioxidant enzymes but also their rapid degradation after inactivation would be regulated in response to ROS levels. Antioxidant enzymes may show dual responses of

  17. Differing long term trends for two common amphibian species (Bufo bufo and Rana temporaria) in alpine landscapes of Salzburg, Austria.

    Science.gov (United States)

    Kyek, Martin; Kaufmann, Peter H; Lindner, Robert

    2017-01-01

    This study focuses on the population trends of two widespread European anuran species: the common toad (Bufo bufo) and the common frog (Rana temporaria). The basis of this study is data gathered over two decades of amphibian fencing alongside roads in the Austrian state of Salzburg. Different statistical approaches were used to analyse the data. Overall average increase or decrease of each species was estimated by calculating a simple average locality index. In addition the statistical software TRIM was used to verify these trends as well as to categorize the data based on the geographic location of each migration site. The results show differing overall trends for the two species: the common toad being stable and the common frog showing a substantial decline over the last two decades. Further analyses based on geographic categorization reveal the strongest decrease in the alpine range of the species. Drainage and agricultural intensification are still ongoing problems within alpine areas, not only in Salzburg. Particularly in respect to micro-climate and the availability of spawning places these changes appear to have a greater impact on the habitats of the common frog than the common toad. Therefore we consider habitat destruction to be the main potential reason behind this dramatic decline. We also conclude that the substantial loss of biomass of a widespread species such as the common frog must have a severe, and often overlooked, ecological impact.

  18. Variation in Chemical Defense Among Natural Populations of Common Toad, Bufo bufo, Tadpoles: the Role of Environmental Factors.

    Science.gov (United States)

    Bókony, Veronika; Móricz, Ágnes M; Tóth, Zsófia; Gál, Zoltán; Kurali, Anikó; Mikó, Zsanett; Pásztor, Katalin; Szederkényi, Márk; Tóth, Zoltán; Ujszegi, János; Üveges, Bálint; Krüzselyi, Dániel; Capon, Robert J; Hoi, Herbert; Hettyey, Attila

    2016-04-01

    Defensive toxins are widespread in nature, yet we know little about how various environmental factors shape the evolution of chemical defense, especially in vertebrates. In this study we investigated the natural variation in the amount and composition of bufadienolide toxins, and the relative importance of ecological factors in predicting that variation, in larvae of the common toad, Bufo bufo, an amphibian that produces toxins de novo. We found that tadpoles' toxin content varied markedly among populations, and the number of compounds per tadpole also differed between two geographical regions. The most consistent predictor of toxicity was the strength of competition, indicating that tadpoles produced more compounds and larger amounts of toxins when coexisting with more competitors. Additionally, tadpoles tended to contain larger concentrations of bufadienolides in ponds that were less prone to desiccation, suggesting that the costs of toxin production can only be afforded by tadpoles that do not need to drastically speed up their development. Interestingly, this trade-off was not alleviated by higher food abundance, as periphyton biomass had negligible effect on chemical defense. Even more surprisingly, we found no evidence that higher predation risk enhances chemical defenses, suggesting that low predictability of predation risk and high mortality cost of low toxicity might select for constitutive expression of chemical defense irrespective of the actual level of predation risk. Our findings highlight that the variation in chemical defense may be influenced by environmental heterogeneity in both the need for, and constraints on, toxicity as predicted by optimal defense theory.

  19. High genetic diversity of common toad (Bufo bufo) populations under strong natural fragmentation on a Northern archipelago.

    Science.gov (United States)

    Roth, Steffen; Jehle, Robert

    2016-03-01

    The last decades have shown a surge in studies focusing on the interplay between fragmented habitats, genetic variation, and conservation. In the present study, we consider the case of a temperate pond-breeding anuran (the common toad Bufo bufo) inhabiting a naturally strongly fragmented habitat at the Northern fringe of the species' range: islands offshore the Norwegian coast. A total of 475 individuals from 19 populations (three mainland populations and 16 populations on seven adjacent islands) were genetically characterized using nine microsatellite markers. As expected for a highly fragmented habitat, genetic distances between populations were high (pairwise F st values ranging between 0.06 and 0.33), with however little differences between populations separated by ocean and populations separated by terrestrial habitat (mainland and on islands). Despite a distinct cline in genetic variation from mainland populations to peripheral islands, the study populations were characterized by overall high genetic variation, in line with effective population sizes derived from single-sample estimators which were on average about 20 individuals. Taken together, our results reinforce the notion that spatial and temporal scales of fragmentation need to be considered when studying the interplay between landscape fragmentation and genetic erosion.

  20. Evaluating factors affecting amphibian mortality on roads: the case of the Common Toad Bufo bufo, near a breeding place

    Directory of Open Access Journals (Sweden)

    Santos, X.

    2007-06-01

    Full Text Available The Common Toad Bufo bufo is the amphibian with the highest rates of road mortality in many European countries. This elevated incidence of road kills has frequently been associated with migration to breeding sites. In this study, we analysed the mortality of the Common Toad in the road network in Catalonia (NE Spain, and investigated the related causative factors on four roads near a breeding site in the Pyrenees. Results suggest that the high mortality rate is due to a combination of factors: toad abundance, traffic density and quality of water bodies for breeding. On the road with the highest incidence of road kills we investigated whether deaths occurred at specific spots or in a random manner. The road was divided into 500 m sections and each section was classified according to biotic (type of vegetation and abiotic (presence of streams, roadside topography variables. Multiple correspondence analysis showed that sections with streams crossing under the road had the highest mortality rate, suggesting that such water bodies flowing into the breeding pond are the toads’ main migratory pathways for hibernation and breeding. As toads use the same migratory routes each year, it is critical to identify areas with a high potential mortality so that efficient measures can be designed to increase wildlife permeability, and thereby reduce habitat fragmentation. This methodology could be applied in other areas with high amphibian mortality.

  1. Comparison of toad venoms from different Bufo species by HPLC and LC-DAD-MS/MS.

    Science.gov (United States)

    Gao, Huimin; Zehl, Martin; Leitner, Alexander; Wu, Xiyan; Wang, Zhimin; Kopp, Brigitte

    2010-09-15

    Toad venom, called Chansu in China, has been widely used for the treatment of heart failure, sores, pains, and various cancers for a long time in clinic. The aim of the study is to investigate the chemical differences among a variety of toad venoms from different geographic locations and related Bufo species. Ten batches of commercial toad venom collected from different regions in China, one batch of fresh toad venom obtained from Bufo bufo gargarizans, and six batches of related Bufo species were analyzed by HPLC and LC-DAD-MS/MS. Individual components were identified by comparison of retention times, UV spectra, and mass spectra with authentic compounds, standard addition, as well as summarized MS fragmentation rules. Based on the profile of identified constituents and the content of cinobufagin and resibufogenin, the chemical differences observed among different samples are discussed. Overall, 43 compounds were identified in the methanolic extracts of the different samples of toad venom. Besides of suberoyl arginine, several free bufadienolides, bufadienolide sulfates, and suberoyl esters of bufadienolides were found. The total amounts of cinobufagin and resibufogenin, which are the only two control markers according to the current Chinese Pharmacopoeia, varied widely from 0.7% to 10.9% in the commercial Chansu samples collected in the different locations in China. Low levels of resibufogenin, but no cinobufagin was observed in the samples from Bufo melanosticus and Bufo marinus, and even neither of both compounds was found in the sample from Bufo viridis. The chemical profiles of the different commercial and collected toad venoms from related Bufo species differed significantly, not only in the absolute and relative contents, but also in the number and type of the constituents. The main reason for this variation are species-specific differences, but additional factors, such as the harvest and post-harvest processing, and adaption to environmental factors in

  2. Lethal and sublethal toxicity of the industrial chemical epichlorohydrin on Rhinella arenarum (Anura, Bufonidae) embryos and larvae.

    Science.gov (United States)

    Hutler Wolkowicz, Ianina R; Aronzon, Carolina M; Pérez Coll, Cristina S

    2013-12-15

    Lethal and sublethal toxicity of the major chemical used in epoxide compounds, epichlorohydrin (ECH) was evaluated on the early life cycle of the common South American toad, Rhinella arenarum (Anura, Bufonidae). The stages evaluated were (according to Del Conte and Sirlin): early blastula (S.3-S.4), gastrula (S.10-S.12), rotation (S.15), tail bud (S.17), muscular response (S.18), gill circulation (S.20), open mouth (S.21), opercular folds (S.23) and complete operculum (S.25). The LC50 and EC50 values for lethal and sublethal effects were calculated. The early blastula was the most sensitive stage to ECH both for continuously and pulse-exposures (LC50-24h=50.9 mg L(-1)), while S.20 was the most resistant (LC50-24h=104.9 mg L(-1)). Among sublethal effects, early blastula was also the most sensitive stage (LOEC-48 h=20 mg L(-1)) and it has a Teratogenic Index of 2.5, which indicates the teratogenic potential of the substance. The main abnormalities were persistent yolk plugs, cell dissociation, tumors, hydropsy, oral malformations, axial/tail flexures, delayed development and reduced body size. ECH also caused neurotoxicity including scarce response to stimuli, reduction in the food intake, general weakness, spasms and shortening, erratic or circular swimming. Industrial contamination is considered an important factor on the decline of amphibian populations. Considering the available information about ECH's toxicity and its potential hazard to the environment, this work shows the first results of its developmental toxicity on a native amphibian species, Rhinella arenarum. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Health status of tadpoles and metamorphs of Rhinella arenarum (Anura, Bufonidae) that inhabit agroecosystems and its implications for land use.

    Science.gov (United States)

    Babini, María Selene; Bionda, Clarisa de Lourdes; Salas, Nancy Edith; Martino, Adolfo Ludovico

    2015-08-01

    Perturbations of water bodies near agricultural and livestock systems can affect embryonic and larval stages of anurans and negatively impact adult populations and structure of amphibian communities. This study is focused on early development of Rhinella arenarum, for which body growth, abnormalities in the oral disc and genetic damage on erythrocytes were analyzed to establish the impact of agroecosystems on local populations of amphibians. Tadpoles and metamorphs of R. arenarum were collected in three agroecosystems (namely, C1, C2, and C3) and in a site without agricultural and livestock activities (SM) from central Argentina. Egg masses of C1 were extracted for breeding tadpoles under laboratory conditions (Lab). Tadpoles were in small size and lighter in weight in C1 and C2. Metamorphs were shorter and lighter in weight in C1 and C3. In SM and Lab samples, no tadpoles with abnormal LTRF (labial tooth row formula) or without labial teeth were observed. In C1, the highest frequency of abnormal LTRF was recorded and was the only site in which tadpoles without labial teeth were found. In C1 and C2 the tadpoles had highest micronucleus frequencies and nuclear abnormalities. C1 can be considered as the site with the highest anthropogenic perturbation and with less healthy tadpoles. Livestock practices such as alternating cattle between parcel and keeping a buffer between crops and water bodies, would allow a better development of the first aquatic stages that are essential for the conservation of the anuran populations. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. [Trophic ecology in tadpoles of Rhinella arenarum (Anura: Bufonidae) in agroecosystems and their possible implications for conservation].

    Science.gov (United States)

    Bionda, Clarisa; Gari, Noemi; Luque, Elisa; Salas, Nancy; Lajmanovich, Rafael; Martino, Adolfo

    2012-06-01

    The progress of the agriculture border has led an important loss of natural habitats, with significant consequences for biodiversity. In this sense, the studies in anuran amphibian tadpoles inhabiting these environments are relevant, because the larval stage is a phase of population regulation. The aim of this study was to analyze the body condition and diet in Rhinella arenarum, tadpoles, an anuran species widely distributed in South America and that inhabit agroecosystems. Three sites were sampled, two agroecosystems with different alteration degrees (C1 and C2) and an uncultured (SM) third place. The captured tadpoles were anesthetized, fixed and preserved in formaldehyde (10%). Subsequently, body measurements were made and the complete intestine was removed and analyzed for food items under a binocular microscope. The diet in R. arenarum tadpoles has a dominance of algae Bacillariophyceae, followed by Cyanophyceae. In particular, the class Bacillariophyceae, due to the presence of the genus Navicula, Nitzschia, Gomphonema and Hantzschia, was important in the diet of the anurans in those agroecosystems. Class Cyanophyceae, mainly represented by genus Oscillatoria and Euglenophyceae represented by Euglena and Strombomonas, were predominant in the diet of the anurans in SM. Some differences in the total items consumed by tadpole were observed between the studied sites. Tadpoles that inhabit the modified sites (C1 and C2) recorded a significantly smaller amount of food. Moreover, the tadpoles that inhabit these sites showed a lower body condition. The presence of certain algae associated with eutrophic environments, could indicate some pollution in agroecosystems (C1 and C2). Food resources would be lesser in places with strong agricultural activity, possibly with a greater degree of eutrophication. A smaller food amount could have consequences at population level for the short and long time terms, because of its impact on individual growth. Larval diet is

  5. Ecología trófica en larvas de Rhinella arenarum (Anura: Bufonidae) en agroecosistemas y sus posibles implicaciones para la conservación

    OpenAIRE

    Clarisa Bionda; Noemi Gari; Elisa Luque; Nancy Salas; Rafael Lajmanovich; Adolfo Martino

    2012-01-01

    El crecimiento de la agricultura produce perdida del habitat natural, con consecuencias para la biodiversidad de los anfibios. Se analizo la dieta y condición corporal de larvas de anuros de Rhinella arenarum que habitan agroecosistemas. Los muestreos fueron realizados en dos agroecosistemas y en un tercer sitio, no afectado por cultivos. Las larvas capturadas fueron anestesiadas, fijadas y preservadas en formaldehido, se realizaron medidas corporales y se analizo la dieta de las larvas. Se r...

  6. Ion transport mechanisms in the mesonephric collecting duct system of the toad Bufo bufo: microelectrode recordings from isolated and perfused tubules

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana

    2004-01-01

    It is not clear how and whether terrestrial amphibians handle NaCl transport in the distal nephron. Therefore, we studied ion transport in isolated perfused collecting tubules and ducts from toad, Bufo bufo, by means of microelectrodes. No qualitative difference in basolateral cell membrane...... and amiloride application showed a small apical Na+ conductance. Arginine vasotocin depolarized Vbl. The small apical Na+ conductance indicates that the collecting duct system contributes little to NaCl reabsorption when compared to aquatic amphibians. In contrast, Vbl rapidly depolarized upon lowering of [Na...

  7. Thallium in spawn, juveniles, and adult common toads (Bufo bufo) living in the vicinity of a zinc-mining complex, Poland

    OpenAIRE

    Dmowski, Krzysztof; Rossa, Monika; Kowalska, Joanna; Krasnodębska-Ostręga, Beata

    2014-01-01

    A breeding population of the common toad Bufo bufo living in the vicinity of a Zn-Pb smelting works in Bukowno, Poland was studied for the presence of thallium. Tl concentration was measured in the bottom sediments of the spawning pond, in the laid eggs, in juveniles after metamorphosis, and in the selected tissues of the adult individuals. A very high concentration of Tl was detected in the spawn (13.97 ± 8.90 mg/kg d.w.). In 50 % of the spawn samples, levels exceeded 20 mgTl/kg d.w. The iss...

  8. Breeding phenology of Bufo viridis Laurenti, 1768 in Sicily

    Directory of Open Access Journals (Sweden)

    Alessandra Sicilia

    2006-11-01

    Full Text Available Bufo viridis Laurenti, 1768 is a common species that inhabits a wide variety of habitats. The different climates characterising its broad range lead to a high degree of variability in its seasonal activity and reproductive cycle. This paper reports some observations carried out on the breeding phenology of this species over a two year period in Mediterranean temporary ponds in Sicily. The reproductive period of Sicilian green toads extends into the autumn months, making it longer than that of other Italian populations. This behaviour seems due to the impact of xeric environmental conditions on the seasonal activity of the studied populations. The present study confirms that B. viridis is an opportunistic breeder with a wide margin of variability in annual reproductive cycle patterns, as would be expected of an ecologically variable species. The duration of the reproductive season varied between populations in the same year and between different years for the same population.

  9. Age-dependent changes in sensitivity to a pesticide in tadpoles of the common toad (Bufo bufo).

    Science.gov (United States)

    Mikó, Zsanett; Ujszegi, János; Hettyey, Attila

    2017-06-01

    The worldwide en masse application of pesticides and the frequently reported malign effects on several non-target organisms underpin the importance of ecotoxicological research on these anthropogenic pollutants. Previous studies showed that sensitivity to herbicides can vary widely depending on additional stress factors, on the species and even on the population investigated. However, there is little information about how sensitivity changes during ontogeny, and how the duration of exposure is linked to the magnitude of malign effects, even though this knowledge would be important for the interpretation of toxicity test results and for formulating recommendations regarding the timing of pesticide application. We exposed tadpoles of the common toad (Bufo bufo) to three concentrations (0, 2 and 4mg a.e./L) of a glyphosate-based herbicide during the 1st, 2nd, 3rd, 4th, or 5th period of larval development or during the entire experiment, and measured survival, time until metamorphosis and body mass at metamorphosis to estimate fitness-consequences. Younger tadpoles were more sensitive to the herbicide in all measured traits than older ones, and this age-dependence was especially pronounced at the high herbicide concentration. Furthermore, tadpoles exposed to the herbicide during the entire experiment developed slower than tadpoles exposed only early on, but we did not observe a similar effect either on body mass or survival. The observed age-dependence of sensitivity to herbicides draws attention to the fact that results of toxicity tests obtained for one age-class are not necessarily generalizable across ontogeny. Also, the age of test animals has to be considered when planning ecotoxicological studies and interpreting their results. Finally, taking into account the temporal breeding habits of local amphibians when planning pesticide application would be highly favourable: if tadpoles would not get exposed to the herbicide during their most sensitive early development

  10. Effects of spirotetramat on the acute toxicity, oxidative stress, and lipid peroxidation in Chinese toad (Bufo bufo gargarizans) tadpoles.

    Science.gov (United States)

    Yin, XiaoHui; Jiang, ShengJu; Yu, Jun; Zhu, GuoNian; Wu, HuiMing; Mao, ChenLei

    2014-05-01

    The aim of this work was to evaluate the potential effects of antioxidant and lipid peroxidation parameters as indicators of exposure to spirotetramat and effects of acute toxicity in the Chinese toad Bufo bufo gargarizans. The results of an acute toxicity test showed that the 72 and 96 h median lethal concentrations (LC(50)) of spirotetramat for tadpoles were 6.98 and 6.45 mg/L, respectively. It indicated that the spirotetramat was moderate toxicity to Chinese toad tadpoles. In a sub-lethal toxicity test, the superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) contents were determined after exposure to 0.03, 0.06, 0.13, 0.65, and 3.23 mg/L for 4, 15, and 30 days. SOD activity significantly in all experimental groups except the highest concentration group increased on day 4 but decreased on days 15 compared with that of the acetone control (P < 0.05). The most sensitive parameters was GSH-Px activity, which significantly increased on day 4, but was inhibited and decreased after prolonged exposure for 15 and 30 days except the lowest concentration treatment group (P < 0.05). The MDA content significantly decreased on day 30 (P < 0.05). During the entire experimental period, sub-lethal doses spirotetramat caused oxidative stress and lipid peroxidation in B. gargarizans tadpoles. These results indicate that sub-lethal even non-lethal spirotetramat are potentially toxic to amphibians. The information presented in this study will be helpful for understanding oxidative stress induced by spirotetramat in aquatic organisms. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Screening breeding sites of the common toad (Bufo bufo) in England and Wales for evidence of endocrine disrupting activity.

    Science.gov (United States)

    Pickford, Daniel B; Jones, Alexandra; Velez-Pelez, Alejandra; Orton, Frances; Iguchi, Taisen; Mitsui, Naoko; Tooi, Osamu

    2015-07-01

    Anuran amphibians are often present in agricultural landscapes and may therefore be exposed to chemicals in surface waters used for breeding. We used passive accumulation devices (SPMD and POCIS) to sample contaminants from nine breeding sites of the Common toad (Bufo bufo) across England and Wales, measuring endocrine activity of the extracts in a recombinant yeast androgen screen (YAS) and yeast estrogen screen (YES) and an in vitro vitellogenin induction screen in primary culture of Xenopus laevis hepatocytes. We also assessed hatching, growth, survival, and development in caged larvae in situ, and sampled metamorphs for gonadal histopathology. None of the SPMD extracts exhibited estrogen receptor or androgen receptor agonist activity, while POCIS extracts from two sites in west-central England exhibited concentration-dependent androgenic activity in the YAS. Three sites exhibited significant estrogenic activity in both the YES and the Xenopus hepatocyte. Hatching rates varied widely among sites, but there was no consistent correlation between hatching rate and intensity of agricultural activity, predicted concentrations of agrochemicals, or endocrine activity measured in YES/YAS assays. While a small number of intersex individuals were observed, their incidence could not be associated with predicted pesticide exposure or endocrine activitity measured in the in vitro screens. There were no significant differences in sex ratio, as determined by gonadal histomorphology among the study sites, and no significant correlation was observed between proportion of males and predicted exposure to agrochemicals. However, a negative correlation did become apparent in later sampling periods between proportion of males and estrogenic activity of the POCIS sample, as measured in the YES. Our results suggest that larval and adult amphibians may be exposed to endocrine disrupting chemicals in breeding ponds, albeit at low concentrations, and that chemical contaminants other than

  12. Effects of a glyphosate-based herbicide on the development of Common toads (Bufo bufo L.; Amphibia) at different temperatures

    Science.gov (United States)

    Baier, Fabian; Gruber, Edith; Spangl, Bernhard; Zaller, Johann G.

    2016-04-01

    Herbicides based on the active ingredient glyphosate are frequently applied in agriculture, horticulture and private gardens all over the world. Recently, leaching of glyphosate or its metabolite (AMPA) into water bodies inhabited by amphibians has been reported. However, very little is known about non-target effects of these herbicides on amphibians and even less is known to what extent different temperatures might alter these effects. Using climate chambers, we investigated the effects of the glyphosate-based herbicide Roundup PowerFlex® (480 g L-1 glyphosate, formulated as 588 g L-1 potassium salt) on the larval development of Common toads (Bufo bufo L.; Amphibia: Anura) under different temperature regimes (15°C vs. 20°C). We established five herbicide concentrations: 0, 1.5, 3, 4 mg acid equivalent L-1 and a 4 mg a.e. L-1 pulse treatment (totally three applications of 1.5, 1.5 and another 1 mg a.e. L-1) at each temperature in a full-factorial design. Each treatment combination was replicated five times, the experiment ran for 24 days. Results showed a highly significant effect of temperature on body length and body width but no effect of herbicide concentration on these growth parameters. Moreover, highly significant interactions between herbicide and temperature on body length and body width were observed suggesting that herbicides had different effects on different temperatures. In conclusion, although Roundup PowerFlex® at the tested concentrations appeared to have no acute toxicity to larvae of Common toads, the observed effects on tadpole morphology will potentially affect competitive interactions in spawning ponds of amphibia. Our findings of herbicide x temperature interactions might become more prevalent when human-induced climate change will lead to more extreme temperatures.

  13. Evaluation of DNA damage in Chinese toad (Bufo bufo gargarizans) after in vivo exposure to sublethal concentrations of four herbicides using the comet assay.

    Science.gov (United States)

    Yin, Xiao Hui; Li, Shao Nan; Zhang, Le; Zhu, Guo Nian; Zhuang, Hui Sheng

    2008-05-01

    Chinese toad, Bufo bufo gargarizans, is frequently found in rice fields, muddy ponds, wetlands and other aquatic ecosystems in China. Because of its habitat, it has many chances of being exposed to pesticides, such as acetochlor, butachlor, chlorimuron-ethyl, and paraquat, which are extensively used in rice or cereal fields. Amphibians may serve as model organisms for determining the genotoxic effects of pollutants contaminating these areas. In the present study DNA damage was evaluated in the Chinese toad using the comet assay, as a potential tool for the assessment of ecogenotoxicity. The first step was to determine the acute toxicity of the above-mentioned herbicides. In acute tests, tadpoles were exposed to a series of relatively high concentrations of acetochlor, butachlor, chlorimuron-ethyl, and paraquat for 96 h. The LC(50 )(96 h) of acetochlor, butachlor, chlorimuron-ethyl and paraquat were measured as 0.76, 1.32, 20.1 and 164 mg l(-1), respectively. Also, negative effects on the behavior of tadpoles were observed with acetochlor, butachlor, and paraquat. Secondly, the comet assay was used for detecting DNA damage in Chinese toad tadpoles exposed to sublethal concentrations of four herbicides. Significant (P Bufo bufo gargarizans for genotoxicity assessment of herbicides.

  14. Stereological analysis of mitochondria in embryos of Rana temporaria and Bufo bufo during cleavage

    Directory of Open Access Journals (Sweden)

    Ewa Krzysztofowicz

    2011-08-01

    Full Text Available Total numbers of mitochondria and their morphology have been quantitatively determined in mature oocytes and in cleaving embryos of two anuran species Rana temporaria and Bufo bufo using stereological methods. Surface densities of inner mitochondrial membranes for both studied species during cleavage ranged from 5.43 m2/cm3 to 7.53 m2/cm3, whereas volume densities of mitochondria did not exceed 1.65%. Since values of these parameters were low, thus embryos during cleavage may be considered as metabolically "silent". Transition of ultrastructural morphology of mitochondria towards that characterising actively respiring organelles occurs at stage 9 for R. temporaria and at stage 8 for B. bufo, correlated with blastula-gastrula and mid-blastula transition, respectively. The total numbers of mitochondria N(c in mature oocytes are as high as 114.8 and 107.2 millions for R. temporaria and B. bufo, respectively, and during cleavage at late blastula stages they increase to 300 millions for both species under study. We suggest that an undefined mechanism might eliminate during cleavage those amphibian embryos which contain small number of mitochondria and low levels of nutrient substances.

  15. Histochemical and structural characterization of egg extra-cellular matrix in bufonid toads, Bufo bufo and Bufotes balearicus: molecular diversity versus morphological uniformity.

    Science.gov (United States)

    Mentino, Donatella; Mastrodonato, Maria; Rossi, Roberta; Scillitani, Giovanni

    2014-11-01

    The extra-cellular matrix of fertilized eggs in the bufonid toads Bufo bufo and Bufotes balearicus was studied to clear the relationships between structural and molecular diversity. Histochemical (PAS, AB pH 2.5 and pH 1.0, Beta-elimination PAS) and lectin-histochemical (Con A, WGA, Succinyl-WGA, PNA, RCA-1, DBA, SBA, AAA, UEA-I, LTA) techniques were used and the observations were made under light and electron microscopy. Both species present a fertilization envelope (FE) and two jelly layers (J1 and J2). The fibers of J2 are shared among the eggs of a clutch in a jelly ribbon. The FE of both species presents neutral glycoproteins, mostly N-linked. In B. bufo there are also residuals of mannose and/or glucose and N-acetylglucosamine. In the FE fibers run parallel to egg's surface or are in bundles or looser hanks with no clear orientation. The J1 layer of both species presents sialosulfoglycoproteins, mostly O-linked, with lactosaminylated, galactosaminylated, glycosaminylated, and fucosylated residuals. A lower amount of galactosaminylated residuals is observed in B. balearicus in respect to B. bufo, whereas the opposite is seen in the amount of fucosylated residuals. The J2 layer is similar in composition to J1 but in B. balearicus there are no glucosaminylated residuals. J layers present fibers and granules that reduce towards J2 . Several microorganisms, in particular blue algae, are observed in the J2 layer of both species. In respect to other species, B. bufo and B. balearicus have a lower number of jelly layers, but a comparable number of glycan types. © 2014 Wiley Periodicals, Inc.

  16. Use of local visual cues for spatial orientation in terrestrial toads (Rhinella arenarum): The role of distance to a goal.

    Science.gov (United States)

    Daneri, M Florencia; Casanave, Emma B; Muzio, Rubén N

    2015-08-01

    The use of environmental visual cues for navigation is an ability present in many groups of animals. The effect of spatial proximity between a visual cue and a goal on reorientation in an environment has been studied in several vertebrate groups, but never previously in amphibians. In this study, we tested the use of local visual cues (beacons) to orient in an open field in the terrestrial toad (Rhinella arenarum). Experiment 1 showed that toads could orient in space using 2 cues located near the rewarded container. Experiment 2 used only 1 cue placed at different distances to the goal and revealed that learning speed was affected by the proximity to the goal (the closer the cue was to the goal, the faster toads learned its location). Experiment 3 showed that the position of a cue results in a different predictive value. Toads preferred cues located closer to the goal more than those located farther away as a reference for orientation. Present results revealed, for the first time, that (a) toads can learn to orient in an open space using visual cues, and that (b) the effect of spatial proximity between a cue and a goal, a learning phenomenon previously observed in other groups of animals such as mammals, birds, fish, and invertebrates, also affects orientation in amphibians. Thus, our results suggest that toads are able to employ spatial strategies that closely parallel those described in other vertebrate groups, supporting an early evolutionary origin for these spatial orientation skills. (c) 2015 APA, all rights reserved).

  17. Evaluation in situ of genotoxicity and stress in South American common toad Rhinella arenarum in environments related to fluorite mine.

    Science.gov (United States)

    Pollo, Favio E; Grenat, Pablo R; Salinas, Zulma A; Otero, Manuel A; Salas, Nancy E; Martino, Adolfo L

    2017-08-01

    Little attention has been paid to the impact of wastewater generated by mining activities on fluoride. In this study, we evaluated the hematology responses of common South American toad Rhinella arenarum inhabiting natural and artificial environments associated with a fluorite mine from central Argentina. We analyzed three sampling stations associated with the fluorite mine: (I) Los Cerros Negros stream (CN), which runs on granitic rock with a high fluorite content; (II) Los Vallecitos stream (LV), which runs on metamorphic rock with low fluorite content; and (III) artificial decantation ponds (DP) containing sediments produced by fluorite flotation process. We calculated frequencies of micronuclei, erythrocyte nuclear abnormalities, mitosis, and immature erythrocytes. In addition, we performed a differential leukocyte count and determined neutrophils/lymphocyte ratio as a stress response estimator. We found high micronucleus (MN) and erythrocyte nuclear abnormality (ENA) frequencies in DP and CN but low frequencies in LV. The neutrophil/lymphocyte ratio was different among sites, with a significant increase in individuals from DP. Values registered in DP could be caused by exposure to mixture of compounds registered in dams that hold wastewater, while high values registered in CN stream might be due to natural concentrations of fluoride. Our results suggest that blood is an effective and non-destructive sensitive indicator for monitoring genotoxic agents in freshwater ecosystems.

  18. Diazinon mediated biochemical changes in the African toad (Bufo regularis

    Directory of Open Access Journals (Sweden)

    Isioma Tongo

    2012-07-01

    Full Text Available The sublethal toxicity of diazinon to the adult African toad, Bufo regularis was assessed using an integration of biomarkers. Changes in acetylcholinesterase (AChE, corticosterone and total protein levels were assessed in the serum, brain, liver, lungs and gastrointestinal tract (GIT and the results supported by bioaccumulation data. The biomarkers were chosen as indicators of key physiological functions: AChE for neurotoxicity, corticosterone and total protein levels as indicators of oxidative stress. Toads were exposed to 0.01, 0.02, 0.03 and 0.04 g/L for 28 days. Brain AChE activity reduced by 96% in the highest concentration (0.04 g/L compared to the control brain. Similarly, AChE activities in serum, liver, lungs and GIT tissues (88%, 88%, 87, 87% umg-1 protein respectively were also inhibited in the toads. Corticosterone and total protein levels in the tissues decreased compared to the control. The accumulation results obtained showed accumulation in the tissues (liver>serum>brain> lung>GIT, with a direct relationship between tissue concentration and changes in the biochemical indices. The alterations in all the indices were significantly concentration dependent. The biomarkers described in this study could be useful complementary indices in the risk assessment of diazinon pesticide.

  19. Ecología trófica en larvas de Rhinella arenarum (Anura: Bufonidae) en agroecosistemas y sus posibles implicaciones para la conservación

    OpenAIRE

    Bionda, Clarisa; Gari, Noemi; Luque, Elisa; Salas, Nancy; Lajmanovich, Rafael; Martino, Adolfo

    2012-01-01

    El crecimiento de la agricultura produce pérdida del hábitat natural, con consecuencias para la biodiversidad de los anfibios. Se analizó la dieta y condición corporal de larvas de anuros de Rhinella arenarum que habitan agroecosistemas. Los muestreos fueron realizados en dos agroecosistemas y en un tercer sitio, no afectado por cultivos. Las larvas capturadas fueron anestesiadas, fijadas y preservadas en formaldehído, se realizaron medidas corporales y se analizó la dieta de las larvas. Se r...

  20. Common toad Rhinella arenarum (Hensel, 1867) and its importance in assessing environmental health: test of micronuclei and nuclear abnormalities in erythrocytes.

    Science.gov (United States)

    Pollo, Favio E; Bionda, Clarisa L; Salinas, Zulma A; Salas, Nancy E; Martino, Adolfo L

    2015-09-01

    Anthropogenic activities may generate significant changes in the integrity of aquatic ecosystems, so long-term monitoring of populations that inhabit them is crucial. Counting micronucleated erythrocytes (MN) and erythrocytic nuclear abnormalities (ENA) in peripheral blood is a widely used method for detecting chromosomal damage due to chemical agents in the water. We analyzed MN and ENA frequency in blood obtained from the common toad Rhinella arenarum populations in sites with different degrees of environmental degradation. The results of this study indicate that there is an association between the frequency of micronuclei and nuclear abnormalities and the degree of environmental alteration recorded for the sites studied.

  1. Selection of diet by metamorphic and juvenile western toads (Bufo boreas) in northeastern Oregon

    Science.gov (United States)

    Evelyn L Bull; Jane L. Hayes

    2009-01-01

    The decline of Bufo boreas, the Western Toad, in portions of its range has accentuated the need for more complete information on all life stages of this species. Our objectives were to describe the diet of recently metamorphosed and juvenile (one-year old) B. boreas and then compare it to the available arthropods. Metamorphs (n...

  2. Habitat modeling and movements of the Yosemite toad (Anaxyrus (=Bufo) canorus) in the Sierra Nevada, California

    Science.gov (United States)

    C.T. Liang

    2010-01-01

    The Yosemite toad (Anaxyrus (=Bufo) canorus) is a high-elevation species endemic to the Sierra Nevada mountain range in California and is part of the world-wide amphibian declines phenomenon. The toad is thought to have disappeared from over 50% of its historic range even in seemingly undisturbed areas, and...

  3. Summer movements of boreal toads (Bufo boreas boreas) in two western Montana basins

    Science.gov (United States)

    David A. Schmetterling; Michael K. Young

    2008-01-01

    The Boreal Toad (Bufo boreas boreas) is widely distributed in the western United States but has declined in portions of its range. Research directed at conserving Boreal Toads has indicated that their movements are largely terrestrial and often limited after the breeding season. We used a combination of stream-based netting, PIT tagging, and radio...

  4. POPULATION STRUCTURE OF THE RED-SPOTTED TOAD, BUFO PUNCTATUS, IN A NATURALLY FRAGMENTED DESERT LANDSCAPE

    Science.gov (United States)

    We investigated the spatial scale at which genetic structure of Bufo punctatus within the MojaveDesert is organized by sequencing a portion of mitochondrial DNA control region for 831 toadscollected from 43 sites around Las Vegas, Nevada. We grouped these collecti...

  5. DIET OF THE SOUTHERN TOAD (BUFO TERRESTRIS) FROM THE SOUTHERN EVERGLADES

    Science.gov (United States)

    We examined the diet of a February-May sample of the southern toad (Bufo terrestris) from the Everglades National Park. Above the familial level, 13 taxa were consumed, but ants (Hymenoptera) and beetles (Coleoptera) were consumed most by, and in the greatest number of sto...

  6. Sexual differences in the ecology and habitat selection of western toads (Bufo boreas) in northeastern Oregon.

    Science.gov (United States)

    Evelyn L. Bull

    2006-01-01

    Several species of toads (family Bufonidae), including the Western Toad (bufo boreas) have declined in the Western United States. Information on toad ecology and habitat use is essential to determine potential causes for population declines, as is the potential relationship between this information and disturbance events. Aspects of western toad...

  7. Short notes and reviews Bidder’s organ in the female of Bufo ictericus: morphological characterization

    NARCIS (Netherlands)

    Farias, C.F.; Brito-Gitirana, de L.; Carvalho-e-Silva, S.P.

    2004-01-01

    Bidder’s organ has been cited as a structure present only in males of the toad family Bufonidae, and is used as a systematic characteristic. In this study, we examined females of Bufo ictericus in order to ascertain whether this structure also occurs in females. Macroscopic observations and light

  8. HABITAT PATCH OCCUPANCY BY THE TOADS (BUFO PUNCTATUS) IN A NATURALLY FRAGMENTED, DESERT LANDSCAPE

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late...

  9. Electrical responses of rods in the retina of Bufo marinus

    Science.gov (United States)

    Cervetto, L.; Pasino, E.; Torre, V.

    1977-01-01

    1. Intracellular responses to flashes and steps of light have been recorded from the outer segment and the cell body of rods in the retina of the Bufo marinus. The identification of the origin of recorded responses has been confirmed by intracellular marking. 2. Responses to flashes delivered in darkness or superimposed on a background were analysed. Responses recorded from outer segments conform to the principle of `spectral univariance'. The shape of the response is not affected by enlarging the spot diameter from 150 to 1000 μm. 3. The membrane potential measured in darkness at the outer segments varied from -15 to -25 mV. Injection of steady hyperpolarizing currents increases the size of the response to light; depolarizing currents reduce the response. The mean value of the input resistance is 97 ± 30 MΩ in darkness and increases by 20-30% during illumination. 4. The responses obtained from the cell body of rods have the same shape, time course and spectral sensitivity of those recorded at the outer segment. Injection of steady current at the cell body produces different effects than at the outer segment: hyperpolarizing currents reduce the amplitude of the response to light; depolarizing currents increase the response. 5. The experimental data are fitted according to a model similar to that used to describe the responses of turtle cones (Baylor & Hodgkin, 1974; Baylor, Hodgkin & Lamb, 1974a, b). 6. The model reproduces the electrical responses of the rod outer segment to a variety of stimuli: (a) brief flashes and steps of light in dark adapted conditions; (b) bright flashes superimposed on background illuminations; (c) pairs of flashes delivered at different time intervals. Responses to hyperpolarizing steps of current are also reproduced by the model. ImagesABCD PMID:406383

  10. Determination of impacts on the endangered Wyoming toad (Bufo baxteri) at Mortenson National Wildlife Refuge from ammonium nitrate concentrations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The endangered Wyoming toad (Bufo baxteri) is found only as a reintroduced population at Mortenson NWR in the Laramie Plains of southeast Wyoming. Reasons for the...

  11. Avoidance responses to scents of snakes that pose different risks of predation by adult natterjack toads, Bufo calamita

    National Research Council Canada - National Science Library

    Gonzalo, Adega; López, Pilar; Martín, José

    2008-01-01

    ... ( Bufo calamita Laurenti, 1768) was influenced by the presence in the refuge of chemical cues from conspecifics or from two different snake predators ( Natrix maura (L., 1758) and Natrix natrix (L., 1758...

  12. Toxicity of four herbicide formulations with glyphosate on Rhinella arenarum (anura: bufonidae) tadpoles: B-esterases and glutathione S-transferase inhibitors.

    Science.gov (United States)

    Lajmanovich, Rafael C; Attademo, Andrés M; Peltzer, Paola M; Junges, Celina M; Cabagna, Mariana C

    2011-05-01

    In this study, amphibian tadpoles Rhinella arenarum were exposed to different concentrations of Roundup Ultra-Max (ULT), Infosato (INF), Glifoglex, and C-K YUYOS FAV. Tadpoles were exposed to these commercial formulations with glyphosate (CF-GLY) at the following concentrations (acid equivalent [ae]): 0 (control), 1.85, 3.75, 7.5, 15, 30, 60, 120, and 240 mg ae/L for 6-48 h (short-term). Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carboxylesterase (CbE), and glutathione S-transferase (GST) activities were measured among tadpoles sampled from those treatments that displayed survival rates >85%. Forty-eight-hour LC(50) for R. arenarum tadpoles exposed to CF-GLY in the static tests ranged from ULT = 2.42 to FAV = 77.52 mg ae/L. For all CF-GLY, the LC(50) values stabilized at 24 h of exposure. Tadpoles exposed to all CF-GLY concentrations at 48 h showed decreases in the activities of AChE (control = 17.50 ± 2.23 nmol/min/mg/protein; maximum inhibition INF 30 mg ae/L, 71.52%), BChE (control = 6.31 ± 0.86 nmol/min/mg/protein; maximum inhibition INF 15 mg ae/L, 78.84%), CbE (control = 4.39 ± 0.46 nmol/min/mg/protein; maximum inhibition INF 15 mg ae/L, 81.18%), and GST (control = 4.86 ± 0.49 nmol/min/mg/protein; maximum inhibition INF 1.87 mg ae/L, 86.12%). These results indicate that CF-GLY produce a wide range of toxicities and that all enzymatic parameters tested may be good early indicators of herbicide contamination in R. arenarum tadpoles.

  13. A microchannel confocal examination of arsenic speciation and distribution in Bufo americanus

    Science.gov (United States)

    Nearing, Michelle M.; Koch, Iris; Gordon, Robert A.; Reimer, Kenneth J.

    2016-05-01

    We have used confocal methods to examine the distribution and speciation of arsenic within amphibian tissue (Bufo americanus) from a contaminated mine site. The use of new microchannel technology permits a confocal, and energy-independent, examination of a given voxel within the amphibian tissue without the need for sectioning. We observe differences in arsenic concentration and speciation depending on tissue type, with the Eberth- Katschenko layer in particular containing Mn, Fe, Cu and Zn in addition to Ca and pentavalent arsenic.

  14. Genotoxic effect of a binary mixture of dicamba- and glyphosate-based commercial herbicide formulations on Rhinella arenarum (Hensel, 1867) (Anura, Bufonidae) late-stage larvae.

    Science.gov (United States)

    Soloneski, Sonia; Ruiz de Arcaute, Celeste; Larramendy, Marcelo L

    2016-09-01

    The acute toxicity of two herbicide formulations, namely, the 57.71 % dicamba (DIC)-based Banvel(®) and the 48 % glyphosate (GLY)-based Credit(®), alone as well as the binary mixture of these herbicides was evaluated on late-stage Rhinella arenarum larvae (stage 36) exposed under laboratory conditions. Mortality was used as an endpoint for determining acute lethal effects, whereas the single-cell gel electrophoresis (SCGE) assay was employed as genotoxic endpoint to study sublethal effects. Lethality studies revealed LC5096 h values of 358.44 and 78.18 mg L(-1) DIC and GLY for Banvel(®) and Credit(®), respectively. SCGE assay revealed, after exposure for 96 h to either 5 and 10 % of the Banvel(®) LC5096 h concentration or 5 and 10 % of the Credit(®) LC5096 h concentration, an equal significant increase of the genetic damage index (GDI) regardless of the concentration of the herbicide assayed. The binary mixtures of 5 % Banvel(®) plus 5 % Credit(®) LC5096 h concentrations and 10 % Banvel(®) plus 10 % Credit(®) LC5096 h concentrations induced equivalent significant increases in the GDI in regard to GDI values from late-stage larvae exposed only to Banvel(®) or Credit(®). This study represents the first experimental evidence of acute lethal and sublethal effects exerted by DIC on the species, as well as the induction of primary DNA breaks by this herbicide in amphibians. Finally, a synergistic effect of the mixture of GLY and DIC on the induction of primary DNA breaks on circulating blood cells of R. arenarum late-stage larvae could be demonstrated.

  15. Primer reporte de parasitismo de una garrapata blanda del género Ornithodoros (Ixodida: Argasidae sobre Rhinella arenarum (Anura: Bufonidae en el departamento de Valle Fértil, San Juan, Argentina

    Directory of Open Access Journals (Sweden)

    Acosta, Juan Carlos

    2012-08-01

    Full Text Available El objetivo de la presente comunicación es reportar por primera vez un caso de parasitismo en Rhinella arenarum y a la vez mencionar el primer registro del género Ornithodoros en el departamento de Valle Fértil, San Juan, Argentina. Siendo el primer registro de parasitismo de anfibios por Ornithodoros en la Argentina y el segundo para el neotrópico.

  16. Concordant morphological and molecular clines in a contact zone of the Common and Spined toad (Bufo bufo and B. spinosus) in the northwest of France.

    Science.gov (United States)

    Arntzen, Jan W; Trujillo, Tania; Butôt, Roland; Vrieling, Klaas; Schaap, Onno; Gutiérrez-Rodríguez, Jorge; Martínez-Solano, Iñigo

    2016-01-01

    Hybrid zones are regions where individuals of two species meet and produce hybrid progeny, and are often regarded as natural laboratories to understand the process of species formation. Two microevolutionary processes can take place in hybrid zones, with opposing effects on population differentiation. Hybridization tends to produce genetic homogenization, reducing species differences, whereas the presence of mechanisms of reproductive isolation result in barriers to gene flow, maintaining or increasing differences between taxa. Here we study a contact zone between two hybridizing toad species, Bufo bufo and B. spinosus, through a combination of molecular (12 polymorphic microsatellites, four nuclear and two mitochondrial SNP markers) and morphological data in a transect in the northwest of France. The results show largely concordant clines across markers, defining a narrow hybrid zone of ca. 30 km wide. Most hybrids in the centre of the contact zone are classified as F2 or backcrossed individuals, with no individuals assigned to the F1 hybrid class. We discuss the implications of these results for our understanding of the evolutionary history of these species. We anticipate that the toad contact zone here described will become an important asset in the study of hybrid zone dynamics and evolutionary biology because of its easy access and the abundance of the species involved.

  17. Thallium in spawn, juveniles, and adult common toads (Bufo bufo) living in the vicinity of a zinc-mining complex, Poland.

    Science.gov (United States)

    Dmowski, Krzysztof; Rossa, Monika; Kowalska, Joanna; Krasnodębska-Ostręga, Beata

    2015-01-01

    A breeding population of the common toad Bufo bufo living in the vicinity of a Zn-Pb smelting works in Bukowno, Poland was studied for the presence of thallium. Tl concentration was measured in the bottom sediments of the spawning pond, in the laid eggs, in juveniles after metamorphosis, and in the selected tissues of the adult individuals. A very high concentration of Tl was detected in the spawn (13.97 ± 8.90 mg/kg d.w.). In 50% of the spawn samples, levels exceeded 20 mgTl/kg d.w. The issue of maternal transfer of thallium from females to oocytes is discussed. Due to a significant accumulation of thallium, spawn analysis can be used as a sensitive indicator of the presence of this element in the environment and may replace more invasive methods that involve the killing of adult animals. In those regions that are abundant in Zn-Pb ores, the spawn of amphibians may be a very important source of thallium contamination for predators. From among all tissues of the Bukowno adult toads, the livers have shown the highest accumulation of thallium (mean 3.98 mg/kg d.w. and maximum value--18.63). For as many as 96.5% of livers, concentrations exceeded 1.0 mgTl/kg d.w. which is treated as indicative of poisoning.

  18. How fast do amphibians disperse? Introductions, distribution and dispersal of the common frog Rana temporaria and the common toad Bufo bufo on a coastal island in Central Norway

    Directory of Open Access Journals (Sweden)

    Dag Dolmen

    2016-04-01

    Full Text Available The common frog (Rana temporaria and the common toad (Bufo bufo were introduced successfully to the coastal island of Frøya in Central Norway several times during 1960–2012. There is still a very high degree of conformity between sites where they were introduced and the present distribution of the two species. However, in western Frøya, a release of frogs about 1996 was followed by a quick expansion of their distribution area; in 2012 and 2013, breeding was registered close to 7 km westwards and eastwards, respectively, i.e. a population dispersal speed of approximately 0.4 km/yr. On eastern Frøya and some small islands in the archipelago, area expansions at another four frog localities have been prevented by ecological barriers like unfavourable limnetic or terrestrial habitats or salty water. Two local common toad populations on eastern Frøya do not show any expansion either. However, an apparently isolated record of the species on western Frøya in 2011 can possibly be explained by the expansion westwards of a population in northern central Frøya, where toads were introduced around 1995. This stretch is about 9.9 km, i.e. an average population dispersal speed of 0.6 km/yr.

  19. Different morphologic formation patterns of dark patches in the black-spotted frog (Pelophylax nigromaculata) and the Asiatic toad (Bufo gargarizans).

    Science.gov (United States)

    Guangming, Gan; Tao, Zhao; Chao, Li; Moyan, Zhao

    2017-01-01

    The black-spotted frog (Pelophylax nigromaculata) and Asiatic toad (Bufo gargarizans), two relatively distantly related species, live in different habitats with different adaptive dark patches. To explain the formation of dark patches, the distribution patterns of melanin granules were examined with light microscopy and transmission electron microscopy. Melanin granules were produced and gathered into the "cap" structures on top of the nuclei in most epidermal cells. The "cap" structures may play a role in forming the dorsal dark patches coupled with three-layer melanophores, which can give rise to three layers of interconnected melanin networks in the dorsal dermis in P. nigromaculata. Epidermal melanocytes are rare and do not have a definitive role in forming dorsal dark patches in either P. nigromaculata or B. gargarizans. In B. gargarizans, the dermal melanophores only give rise to a single-layered melanin network, which hardly results in dark patches in the dorsal skin. However, the dermal melanophores migrate twice and form into pseudostratified networks, leading to dark patch formation in the ventral skin in B. gargarizans. The melanin granules precisely coregulate dark patches in the dermis and/or epidermis in P. nigromaculata and B. gargarizans. The dark patch formation depends on melanin granules in the epidermis or/and dermis in P. nigromaculata and B. gargarizans.

  20. Volunteer Conservation Action Data Reveals Large-Scale and Long-Term Negative Population Trends of a Widespread Amphibian, the Common Toad (Bufo bufo).

    Science.gov (United States)

    Petrovan, Silviu O; Schmidt, Benedikt R

    2016-01-01

    Rare and threatened species are the most frequent focus of conservation science and action. With the ongoing shift from single-species conservation towards the preservation of ecosystem services, there is a greater need to understand abundance trends of common species because declines in common species can disproportionately impact ecosystems function. We used volunteer-collected data in two European countries, the United Kingdom (UK) and Switzerland, since the 1970s to assess national and regional trends for one of Europe's most abundant amphibian species, the common toad (Bufo bufo). Millions of toads were moved by volunteers across roads during this period in an effort to protect them from road traffic. For Switzerland, we additionally estimated trends for the common frog (Rana temporaria), a similarly widespread and common amphibian species. We used state-space models to account for variability in detection and effort and included only populations with at least 5 years of data; 153 populations for the UK and 141 for Switzerland. Common toads declined continuously in each decade in both countries since the 1980s. Given the declines, this common species almost qualifies for International Union for the Conservation of Nature (IUCN) red-listing over this period despite volunteer conservation efforts. Reasons for the declines and wider impacts remain unknown. By contrast, common frog populations were stable or increasing in Switzerland, although there was evidence of declines after 2003. "Toads on Roads" schemes are vital citizen conservation action projects, and the data from such projects can be used for large scale trend estimations of widespread amphibians. We highlight the need for increased research into the status of common amphibian species in addition to conservation efforts focusing on rare and threatened species.

  1. Body size, nuptial pad size and hormone levels: potential non-destructive biomarkers of reproductive health in wild toads (Bufo bufo).

    Science.gov (United States)

    Orton, Frances; Baynes, Alice; Clare, Frances; Duffus, Amanda L J; Larroze, Severine; Scholze, Martin; Garner, Trenton W J

    2014-09-01

    Amphibians are declining and fertility/fecundity are major drivers of population stability. The development of non-destructive methods to assess reproductive health are needed as destructive measures are fundamentally at odds with conservation goals for declining species. We investigated the utility of body size, nuptial pad size and forelimb width as non-destructive biomarkers of internal reproductive physiology, by analysing correlations with commonly used destructive methods in adult male toads (Bufo bufo) from a low human impact and a high human impact site. Principal component analyses revealed that size was the most important variable for explaining inter-individual differences in other measured endpoints, both non-destructive and destructive, except for hormone levels and nuptial pad, which were independent of size. Toads from the LI and the HI site differed in almost all of the measured endpoints; this was largely driven by the significantly smaller size of toads from the HI site. Correlational analyses within sites revealed that size was correlated with several reproductive endpoints in toads from the HI site but not the LI site, indicating a possible limiting effect of size on reproductive physiology. Intersex was observed in 33% of toads from the HI site and incidence was not related to any other measured endpoint. In conclusion, we provide evidence that size is associated with reproductive physiology and that nuptial pad/hormone levels have potential as additional markers due to their independence from size. We also show that human activities can have a negative effect on reproductive physiology of the common toad.

  2. Exposure and post-exposure effects of endosulfan on Bufo bufo tadpoles: morpho-histological and ultrastructural study on epidermis and iNOS localization.

    Science.gov (United States)

    Bernabò, Ilaria; Guardia, Antonello; La Russa, Daniele; Madeo, Giuseppe; Tripepi, Sandro; Brunelli, Elvira

    2013-10-15

    Endosulfan is a persistent organic pollutant (POP) that has lethal and sublethal effects on non-target organisms, including amphibians. In a laboratory study, we investigated direct and post-exposure effects of endosulfan on Bufo bufo tadpoles. For this purpose we exposed the tadpoles to a single short-term contamination event (96 h) at an environmentally-realistic concentration (200 μg endosulfan/L). This was followed by a recovery period of 10 days when the experimental animals were kept in pesticide-free water. The endpoints were assessed in terms of mortality, incidence of deformity, effects on behavior, and the morpho-functional features of the epidermis. We found that a short-term exposure to the tested concentration of endosulfan did not cause mortality but induced severe sublethal effects, such as hyperactivity, convulsions, and axis malformations. Following relocation to a pesticide-free environment, we noted two types of response within the experimental sample, in terms of morphological and behavioral traits. Moreover, by using both ultrastructural and a morpho-functional approach, we found that a short-term exposure to endosulfan negatively affected the amphibian epidermis. We also observed several histo-pathological alterations: increased mucous secretion, an increase in intercellular spaces and extensive cell degeneration, together with the induction of an inducible isoform of nitric oxide synthase (iNOS). Following the post-exposure period, we found large areas of epidermis in which degeneration phenomena were moderate or absent, as well as a further increase in iNOS immunoreactivity. Thus, after 10 days in a free-pesticide environment, the larval epidermis was able to partially replace elements that had been compromised due to a physiological and/or a pathological response to the pesticide. These results highlight the need for both exposure and post-exposure experiments, when attempting to assess pollutant effects. Copyright © 2013 Elsevier B

  3. The Effects of the Toxic Cyanobacterium Limnothrix (Strain AC0243) on Bufo marinus Larvae

    Science.gov (United States)

    Daniels, Olivia; Fabbro, Larelle; Makiela, Sandrine

    2014-01-01

    Limnothrix (strain AC0243) is a cyanobacterium, which has only recently been identified as toxin producing. Under laboratory conditions, Bufo marinus larvae were exposed to 100,000 cells mL−1 of Limnothrix (strain AC0243) live cultures for seven days. Histological examinations were conducted post mortem and revealed damage to the notochord, eyes, brain, liver, kidney, pancreas, gastrointestinal tract, and heart. The histopathological results highlight the toxicological impact of this strain, particularly during developmental stages. Toxicological similarities to β-N-Methylamino-l-alanine are discussed. PMID:24662524

  4. Toxicity of mine drainage to embryonic and larval boreal toads (Bufonidae: Bufo boreas)

    Energy Technology Data Exchange (ETDEWEB)

    Porter, K.R.; Hakanson, D.E.

    1976-05-17

    Chemical analyses and bioassays of mine drainage were made to determine if it could be a factor accounting for the absence of amphibians from Clear Creek County, Colorado. The concentrations of hydrogen ion, iron, copper and zinc in the drainage were all individually much greater than the tolerance levels of premetamorphic toads. The lethality of the drainage was found to be of such a magnitude that it required diluting approximately one thousand times before larvae could survive in it. Boreal toad (Bufo boreas) larvae are more resistant to acidity than most fish but are very similar to other anuran larvae and salmonids in their sensitivity to copper and zinc. (auth)

  5. Karyological and flow cytometric evidence of triploid specimens in Bufo viridis (Amphibia Anura

    Directory of Open Access Journals (Sweden)

    D Cavallo

    2010-01-01

    Full Text Available Karyological and flow cytometric (FCM analyses were performed on a group of 14 green toads of the Bufo viridis species from seven Eurasian populations. Both approaches gave concordant results concerning the DNA ploidy level. All the populations examined were represented exclusively by diploid or tetraploid specimens, except one, where triploids were found. Results evidenced an interpopulation variability in DNA content against the same ploidy level, as well as an unusually high number of triploids in a particular reproductive place. The origin of polyploidy and the presence and persistence of a high number of triploids in a particular population are discussed.

  6. Ecología trófica en larvas de Rhinella arenarum (Anura: Bufonidae en agroecosistemas y sus posibles implicaciones para la conservación Trophic ecology in tadpoles of Rhinella arenarum (Anura: Bufonidae in agroecosystems and their possible implications for conservation

    Directory of Open Access Journals (Sweden)

    Clarisa Bionda

    2012-06-01

    Full Text Available El crecimiento de la agricultura produce perdida del habitat natural, con consecuencias para la biodiversidad de los anfibios. Se analizo la dieta y condición corporal de larvas de anuros de Rhinella arenarum que habitan agroecosistemas. Los muestreos fueron realizados en dos agroecosistemas y en un tercer sitio, no afectado por cultivos. Las larvas capturadas fueron anestesiadas, fijadas y preservadas en formaldehido, se realizaron medidas corporales y se analizo la dieta de las larvas. Se registro diversidad en la oferta alimenticia proporcionada por los distintos ambientes. La dieta tuvo una predominancia de algas Bacillarophyceae, seguidas por Cyanophyceae. Particularmente, los géneros Navicula, Nitzschia, Hantzschia y Gomphonema (clase Bacillarophyceae, fueron importantes en los agroecosistemas. Los géneros Osillatoria, Euglena y Strombomonas (clases Cyanophyceae y Euglenophyceae, predominaron en la dieta de las larvas de anuros en el sitio menos alterado. Las larvas de los sitios más alterados consumen menor cantidad de alimento y registran una menor condición corporal. La presencia de determinadas algas, indicarían un mayor grado de contaminación en los agroecosistemas. La eutrofización de lagunas podría alterar la disponibilidad de alimento para larvas de anuros que podría tener consecuencias poblacionales negativas. Se sugiere el análisis de dietas larvarias como un potencial bioindicador de salubridad ambiental.Trophic ecology in tadpoles of Rhinella arenarum (Anura: Bufonidae in agroecosystems and their possible implications for conservation. The progress of the agriculture border has led an important loss of natural habitats, with significant consequences for biodiversity. In this sense, the studies in anuran amphibian tadpoles inhabiting these environments are relevant, because the larval stage is a phase of population regulation. The aim of this study was to analyze the body condition and diet in Rhinella arenarum

  7. PHYLOGEOGRAPHY OF BUFO PUNCTATUS: LONG TERM EVOLUTION WITHIN THE WARM DESERTS OF NORTH AMERICA AND LATE QUATERNARY RANGE SHIFTING

    Science.gov (United States)

    Bufo punctatus, the red-spotted toad, is a widespread anuran of the warm-desert regions of western North America. This distribution makes this species ideal for evaluating biotic response to geotectonically and climatically mediated episodes of landscape transformation (e.g., ear...

  8. WHEN A PHYLOGENETIC TRICHOTOMY MAKES SENSES: PHYLOGEOGRAPHY OF BUFO PUNCTATUS AND THE EVOLUTION OF THE WARM DESERTS

    Science.gov (United States)

    Bufo punctatus, the red-spotted toad, is a common, desert-adapted anuran with a widespread distribution throughout warm, and regions of North America. This distribution makes this species ideal for evaluating alternative scenarios of biotic response to geotectonically and climat...

  9. HABITAT PATCH OCCUPANCY BY THE RED-SPOTTED TOAD (BUFO PUNCTATUS) IN A NATURALLY FRAGMENTED, DESERT LANDSCAPE

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo panctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the la...

  10. Post-breeding habitat use by adult boreal toads (Bufo boreas boreas) after wildfire in Glacier National Park, USA

    Science.gov (United States)

    C. Gregory Guscio; Blake R. Hossack; Lisa A. Eby; Paul Stephen Corn

    2008-01-01

    Effects of wildfire on amphibians are complex, and some species may benefit from the severe disturbance of stand-replacing fire. Boreal Toads (Bufo boreas boreas) in Glacier National Park, Montana, USA increased in occurrence after fires in 2001 and 2003. We used radio telemetry to track adult B. boreas in a mosaic of terrestrial...

  11. METAPOPULATION PROCESSES OR INFINITE DISPERSAL?: HABITAT PATCH OCCUPANCY BY TOADS (BUFO PUNCTATUS) IN A NATURALLY FRAGMENTED DESERT LANDSCAPE

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late P...

  12. METAPOPULATION PROCESSES OF INFINITE DISPERSAL?: HABITAT PATCH OCCUPANCY BY TOADS (BUFO PUNCTATUS) IN A NATURALLY FRAGMENTED DESERT

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late P...

  13. METAPOPULATION PROCESSES OF INFINITE DISPERSAL: HABITAT PATCH OCCUPANCY BY TOADS (BUFO PUNCTATUS) IN A NATURALLY FRAGMENTED DESERT LANDSCAPE

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late P...

  14. Age-related seasonal variation in captures of stream-borne Boreal Toads (Bufo boreas boreas, Bufonidae) in western Montana

    Science.gov (United States)

    Michael K. Young; David A. Schmetterling

    2009-01-01

    Like many species of amphibians, Boreal Toads (Bufo boreas boreas, Bufonidae) are declining throughout portions of their range. Recent efforts have focused on describing the ecology of this species, yet few studies have evaluated demographic characteristics that may influence the persistence of Boreal Toad populations. Because Boreal Toads often...

  15. METAPOPULATION PROCESSES OR INFINITE DISPERSAL?: HABITAT PATCH OCCUPANCY BY TOADS (BUFO PUNCTATUS) IN A NAUTRALLY FRAGMENTED DESERT LANDSCAPE

    Science.gov (United States)

    Amphibians are often thought to have a metapopulation structure, which may render them vulnerable to habitat fragmentation. The red-spotted toad (Bufo punctatus) in the southwestern USA and Mexico commonly inhabits wetlands that have become much smaller and fewer since the late P...

  16. Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations

    Science.gov (United States)

    Kurtis R. Moseley; Steven B. Castleberry; James L. Hanula; W. Mark Ford

    2004-01-01

    In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo tmrestns) in upland loblolly pine (Pinus taeda) stands...

  17. Movements and habitat use of Yosemite toads (Anaxyrus (formerly Bufo) canorus) in the Sierra National Forest, California

    Science.gov (United States)

    Christina T. Liang

    2013-01-01

    The Yosemite Toad (Anaxyrus (Bufo) canorus) is a high-elevation species endemic to the central Sierra Nevada mountain range in California whose populations are in decline. There is limited information on their terrestrial movement and habitat use, which impairs our understanding of the ecology and habitat...

  18. Wildfire effects on water temperature and selection of breeding sites by the boreal toad (Bufo boreas) in seasonal wetlands

    Science.gov (United States)

    Blake R. Hossack; Paul Stephen Corn

    2008-01-01

    Disturbances can significantly affect the thermal regime and community structure of wetlands. We investigated the effect of a wildfire on water temperature of seasonal, montane wetlands after documenting the colonization of recently burned wetlands by the Boreal Toad (Bufo boreas boreas). We compared the daily mean temperature, daily maximum...

  19. Population Genetic Structure and Species Status of Asiatic Toads (Bufo gargarizans) in Western China.

    Science.gov (United States)

    Wen, Guannan; Yang, Weizhao; Fu, Jinzhong

    2015-10-01

    We investigated the population genetic structure of Asiatic toads (Bufo gargarizans) from the mountains of western China to determine their species status, using genotypic data of ten microsatellite DNA loci and DNA sequences from one mitochondrial gene. A total of 197 samples from eight sites were examined, which cover a large range of elevations (559-3457 m), as well as all three traditionally defined species (or subspecies). AMOVA did not reveal any particularly large among-groups structure, whether the sites were grouped by drainage, elevation, region, or species (subspecies). Individual assignment tests placed all samples into two genetic clusters, which largely corresponded to their geographic locations. An isolation-by-distance pattern was also detected when an outlier population (site 3) was excluded. Furthermore, a mitochondrial gene tree revealed deep divergence among haplotypes, sometimes within the same site. The clade patterns were partially associated with geographic distribution but had no resemblance to the traditional 2- or 3-species classification. Overall, these toad populations harbor a large amount of genetic diversity and have very high population differentiation, but taken together the evidence suggests that all populations belong to a single species. Our results are consistent with most previous molecular studies, and we recommend using Bufo gargarizans to represent all Asiatic toad populations from western China without subspecies division.

  20. Haematological changes in Bufo maculatus treated with sublethal concentrations of Cadmium

    Directory of Open Access Journals (Sweden)

    Lawrence Ikechukwu Ezemonye

    2011-12-01

    Full Text Available Adult Bufo maculatus was exposed to sublethal cadmium concentrations of 0.25, 0.50, 1.00 and 2.00 mg/L. The toxicant from which the cadmium concentrations were prepared was cadmium chloride (CdCl2.H2O. There were three replicate tanks per treatment and three individuals per tank including control groups. The hematologic alterations based on the examination of blood indices during the 28 days of exposure showed that total erythrocyte count (TEC, hematocrit (Hct and hemoglobin (Hb concentration decreased (P<0.05 relative to controls. The decline was concentration- dependent as concentration of cadmium increased. The decline in hemoglobin and hematocrit in the experimental organism could be due to a decrease in the synthesis or release of erythrocytes into the circulation or an increase in the rate of erythrocyte destruction inflicted by cadmium toxicity. There was significant (P<0.05 elevation in total leuko- leukocyte count (TLC with increase in the concen- cyte concentration of cadmium. The increase in total leukocyte count observed in this study could be attributed to a stimulation of the immune system in response to tissue damage caused by cadmium toxicity. The study has shown that the exposure of the Bufo maculatus toad to cadmium can inflict alterations in the hematologic indices, which could induce unfavorable physiological changes in the amphibian, which may lead to death. There is, therefore, the need to protect amphibians in order to sustain the biodiversity in the Nigerian Niger Delta ecological zone.

  1. Lankesterella poeppigii n. sp. (Apicomplexa, Lankesterellidae from Bufo poeppigii (Tschudi, 1845 from Peru

    Directory of Open Access Journals (Sweden)

    Ilan Paperna

    2011-07-01

    Full Text Available Lankesterella poeppigii n. sp. is described from Bufo poeppigii (Tschudi, 1845 from Peru. Merogony and oogony occur in the capillary endothelium and the macrophages in the liver, spleen and kidneys. Meronts are oval, 25,2–29,4 x 15,7–16,8 μm in size and yield 35–46 merozoites. Oocysts are 26,3–29,4 x 15,1–17,6 μm in size; sporozoites 9,2-9,8 x 4,2–5,0 μm in size, assemble in macrophages. Released 8,7–9,8 x 2,8–3,1 μm sporozoites enter erythrocytes. L. poeppigii is compared with Lankesterella petiti Lainson & Paperna, 1995 infecting Bufo marinus (Linnaeus, 1758 in Brazil. The above mentioned specific characters, added to differences in hosts and geographical location warrant the description of Lankesterella poeppigii from B. poeppigii as a new species.

  2. Demografía poblacional de Rhinella arenarum (Anura: Bufonidae y Physalaemus biligonigerus (Anura: Leiuperidae en agroecosistemas de la provincia de Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    Clarisa Bionda

    2013-09-01

    Full Text Available El crecimiento de la agricultura produce pérdida del hábitat natural, con consecuencias para la biodiversidad de los anfibios. Se analizó la demografía poblacional de dos especies de anfibios en agroecosistemas de la provincia de Córdoba, Rhinella arenarum y Physalaemus biligonigerus. Los muestreos se realizaron en tres agroecosistemas y en un cuarto sitio, no afectado por cultivos. Los individuos se capturaron utilizando trampas de caída viva y relevamientos visuales. Con los datos de abundancia se estimó la supervivencia para cada clase de edad y con las tasas de supervivencia y fertilidad poblacional, se construyeron matrices de Leslie para obtener una proyección cuantitativa del tamaño poblacional. Las proyecciones poblacionales fueron favorables para el sitio SM2 y desfavorables para los sitios cultivados. Los agroecosistemas son ambientes posiblemente inhóspitos para la reproducción y supervivencia de las especies estudiadas. Particularmente se ven afectados aquellos estadios acuáticos del ciclo de vida de estas especies, debido al deterioro de los cuerpos de agua en estas áreas. Se reconocieron efectos especie-específicos de los ecosistemas agrícolas, ya que P. biligonigerus resultó la especie más afectada. Se sugiere un deterioro ambiental producido por cultivos extensivos de soja, lo que impactaría la demografía de las poblaciones de anuros.

  3. Ecología trófica en larvas de Rhinella arenarum (Anura: Bufonidae en agroecosistemas y sus posibles implicaciones para la conservación

    Directory of Open Access Journals (Sweden)

    Clarisa Bionda

    2012-06-01

    Full Text Available El crecimiento de la agricultura produce perdida del habitat natural, con consecuencias para la biodiversidad de los anfibios. Se analizo la dieta y condición corporal de larvas de anuros de Rhinella arenarum que habitan agroecosistemas. Los muestreos fueron realizados en dos agroecosistemas y en un tercer sitio, no afectado por cultivos. Las larvas capturadas fueron anestesiadas, fijadas y preservadas en formaldehido, se realizaron medidas corporales y se analizo la dieta de las larvas. Se registro diversidad en la oferta alimenticia proporcionada por los distintos ambientes. La dieta tuvo una predominancia de algas Bacillarophyceae, seguidas por Cyanophyceae. Particularmente, los géneros Navicula, Nitzschia, Hantzschia y Gomphonema (clase Bacillarophyceae, fueron importantes en los agroecosistemas. Los géneros Osillatoria, Euglena y Strombomonas (clases Cyanophyceae y Euglenophyceae, predominaron en la dieta de las larvas de anuros en el sitio menos alterado. Las larvas de los sitios más alterados consumen menor cantidad de alimento y registran una menor condición corporal. La presencia de determinadas algas, indicarían un mayor grado de contaminación en los agroecosistemas. La eutrofización de lagunas podría alterar la disponibilidad de alimento para larvas de anuros que podría tener consecuencias poblacionales negativas. Se sugiere el análisis de dietas larvarias como un potencial bioindicador de salubridad ambiental.

  4. Variación ontogenética en la palatibilidad de los renacuajos de Bufo spinulosus papillosus Philippi, 1902 (Anura: Bufonidae

    Directory of Open Access Journals (Sweden)

    Jara, Fabián Gastón

    2006-03-01

    Full Text Available Se evaluó la variación ontogenética de la palatabilidad en Bufo spinulosus papillosus expuestos a larvas del odonato Rhionaeshna variegata (Odonata, Aeshnidae. Los renacuajos fueron agrupados en cuatro categorías de desarrollo y fueron expuestos a la depredación directa determinándose el número de renacuajos consumidos al finalizar los experimentos. Bufo spinulosus papillosus no fue palatable en los primeros estadios del desarrollo (categorías I, estadios 24-26 y categoría II, estadios 32-34, mientras que los estadios de las categoría III (estadios 38-40 y categoría IV (estadios 42-45 fueron progresivamente palatables. Se observó un comportamiento de rechazo por parte de los depredadores luego de la captura de renacuajos de las categorías I y II. El patrón de palatabilidad encontrado en Bufo spinulosus papillosus difiere del observado en otras especies relacionadas del género Bufo (Brodie y Formanowicz, 1987; Kehr y Schnack, 1991; Lawler y Hero, 1997. We evaluated the ontogenetic variation in the palatability of Bufo spinulosus papillosus tadpoles exposed to odonate larvae of Rhionaeshna variegata (Odonata, Aeshnidae. We exposed tadpoles to direct predation and determined the number of consumed tadpoles in four developmental categories. Bufo spinulosus papillosus tadpoles of categories I (stages 24-26 and II (stages 32-34 were unpalatable, while categories III (stages 38-40 and IV (stages 42-45 were progressively palatable. We observed a post-capture rejection behavior when they caught unpalatable tadpoles in categories I and II. The palatability pattern observed in Bufo spinulosus papillosus was different from related Bufo species (Brodie and Formanowicz, 1987; Kehr and Schnack, 1991; Lawler and Hero, 1997.

  5. Non-target effects of a glyphosate-based herbicide on Common toad larvae (Bufo bufo, Amphibia) and associated algae are altered by temperature

    Science.gov (United States)

    Baier, Fabian; Gruber, Edith; Bondar-Kunze, Elisabeth; Ivanković, Marina; Mentler, Axel; Brühl, Carsten A.; Spangl, Bernhard

    2016-01-01

    Background Glyphosate-based herbicides are the most widely used pesticides in agriculture, horticulture, municipalities and private gardens that can potentially contaminate nearby water bodies inhabited by amphibians and algae. Moreover, the development and diversity of these aquatic organisms could also be affected by human-induced climate change that might lead to more periods with extreme temperatures. However, to what extent non-target effects of these herbicides on amphibians or algae are altered by varying temperature is not well known. Methods We studied effects of five concentrations of the glyphosate-based herbicide formulation Roundup PowerFlex (0, 1.5, 3, 4 mg acid equivalent glyphosate L−1 as a one time addition and a pulse treatment of totally 4 mg a.e. glyphosate L−1) on larval development of Common toads (Bufo bufo, L.; Amphibia: Anura) and associated algae communities under two temperature regimes (15 vs. 20 °C). Results Herbicide contamination reduced tail growth (−8%), induced the occurrence of tail deformations (i.e. lacerated or crooked tails) and reduced algae diversity (−6%). Higher water temperature increased tadpole growth (tail and body length (tl/bl) +66%, length-to-width ratio +4%) and decreased algae diversity (−21%). No clear relation between herbicide concentrations and tadpole growth or algae density or diversity was observed. Interactive effects of herbicides and temperature affected growth parameters, tail deformation and tadpole mortality indicating that the herbicide effects are temperature-dependent. Remarkably, herbicide-temperature interactions resulted in deformed tails in 34% of all herbicide treated tadpoles at 15 °C whereas no tail deformations were observed for the herbicide-free control at 15 °C or any tadpole at 20 °C; herbicide-induced mortality was higher at 15 °C but lower at 20 °C. Discussion These herbicide- and temperature-induced changes may have decided effects on ecological interactions in

  6. Non-target effects of a glyphosate-based herbicide on Common toad larvae (Bufo bufo, Amphibia and associated algae are altered by temperature

    Directory of Open Access Journals (Sweden)

    Fabian Baier

    2016-11-01

    Full Text Available Background Glyphosate-based herbicides are the most widely used pesticides in agriculture, horticulture, municipalities and private gardens that can potentially contaminate nearby water bodies inhabited by amphibians and algae. Moreover, the development and diversity of these aquatic organisms could also be affected by human-induced climate change that might lead to more periods with extreme temperatures. However, to what extent non-target effects of these herbicides on amphibians or algae are altered by varying temperature is not well known. Methods We studied effects of five concentrations of the glyphosate-based herbicide formulation Roundup PowerFlex (0, 1.5, 3, 4 mg acid equivalent glyphosate L−1 as a one time addition and a pulse treatment of totally 4 mg a.e. glyphosate L−1 on larval development of Common toads (Bufo bufo, L.; Amphibia: Anura and associated algae communities under two temperature regimes (15 vs. 20 °C. Results Herbicide contamination reduced tail growth (−8%, induced the occurrence of tail deformations (i.e. lacerated or crooked tails and reduced algae diversity (−6%. Higher water temperature increased tadpole growth (tail and body length (tl/bl +66%, length-to-width ratio +4% and decreased algae diversity (−21%. No clear relation between herbicide concentrations and tadpole growth or algae density or diversity was observed. Interactive effects of herbicides and temperature affected growth parameters, tail deformation and tadpole mortality indicating that the herbicide effects are temperature-dependent. Remarkably, herbicide-temperature interactions resulted in deformed tails in 34% of all herbicide treated tadpoles at 15 °C whereas no tail deformations were observed for the herbicide-free control at 15 °C or any tadpole at 20 °C; herbicide-induced mortality was higher at 15 °C but lower at 20 °C. Discussion These herbicide- and temperature-induced changes may have decided effects on ecological

  7. Non-target effects of a glyphosate-based herbicide on Common toad larvae (Bufo bufo, Amphibia) and associated algae are altered by temperature.

    Science.gov (United States)

    Baier, Fabian; Gruber, Edith; Hein, Thomas; Bondar-Kunze, Elisabeth; Ivanković, Marina; Mentler, Axel; Brühl, Carsten A; Spangl, Bernhard; Zaller, Johann G

    2016-01-01

    Glyphosate-based herbicides are the most widely used pesticides in agriculture, horticulture, municipalities and private gardens that can potentially contaminate nearby water bodies inhabited by amphibians and algae. Moreover, the development and diversity of these aquatic organisms could also be affected by human-induced climate change that might lead to more periods with extreme temperatures. However, to what extent non-target effects of these herbicides on amphibians or algae are altered by varying temperature is not well known. We studied effects of five concentrations of the glyphosate-based herbicide formulation Roundup PowerFlex (0, 1.5, 3, 4 mg acid equivalent glyphosate L -1 as a one time addition and a pulse treatment of totally 4 mg a.e. glyphosate L -1 ) on larval development of Common toads ( Bufo bufo , L.; Amphibia: Anura) and associated algae communities under two temperature regimes (15 vs. 20 °C). Herbicide contamination reduced tail growth (-8%), induced the occurrence of tail deformations (i.e. lacerated or crooked tails) and reduced algae diversity (-6%). Higher water temperature increased tadpole growth (tail and body length (tl/bl) +66%, length-to-width ratio +4%) and decreased algae diversity (-21%). No clear relation between herbicide concentrations and tadpole growth or algae density or diversity was observed. Interactive effects of herbicides and temperature affected growth parameters, tail deformation and tadpole mortality indicating that the herbicide effects are temperature-dependent. Remarkably, herbicide-temperature interactions resulted in deformed tails in 34% of all herbicide treated tadpoles at 15 °C whereas no tail deformations were observed for the herbicide-free control at 15 °C or any tadpole at 20 °C; herbicide-induced mortality was higher at 15 °C but lower at 20 °C. These herbicide- and temperature-induced changes may have decided effects on ecological interactions in freshwater ecosystems. Although no clear dose

  8. Skin Biopsy

    Science.gov (United States)

    ... The Procedure Safety Results en español Biopsia de piel What Is a Skin Biopsy and Who Would ... skin infections, such as staph diseases, such as cancer other medical problems that may affect the skin, ...

  9. Characterization of the mitochondrial genome of Bufo gargarizans minshanicus (Anura: Bufonidae).

    Science.gov (United States)

    Yang, Jiandong; Liu, Jiabin; Xue, Rui; Chen, Limin

    2016-09-01

    The complete mitogenome of Bufo gargarizans minshanicus is 17,719 bp in size, and shares a conserved gene arrangement, gene content and base composition with other Bufonidae species. The base composition of the H-strand is biased toward A + T content at 56.97% (T 28.14%, C 27.67%, A 28.83% and G 15.36%). Most protein-coding genes (PCGs) begin with ATG, while COX1 and ND2 initiate with ATA and ND1 starts at ATT. Seven PCGs have the complete stop codons AGA and TAA, whereas the remaining four PCGs end with TA or T. The putative control region possesses two repeat motifs, and four termination-associated sequences and six conserved sequence blocks at the 5' and 3' ends.

  10. Rhabdias pseudosphaerocephala infection in Bufo marinus: lung nematodes reduce viability of metamorph cane toads.

    Science.gov (United States)

    Kelehear, C; Webb, J K; Shine, R

    2009-07-01

    Cane toads (Bufo marinus) were introduced to Australia in 1935 and have since spread widely over the continent, generating concern regarding ecological impacts on native predators. Most Australian cane toad populations are infected with lung nematodes Rhabdias pseudosphaerocephala, a parasite endemic to New World (native-range) cane toad populations; presumably introduced to Australia with its toad host. Considering the high intensities and prevalence reached by this parasite in Australian toad populations, and public ardour for developing a control plan for the invasive host species, the lack of experimental studies on this host-parasite system is surprising. To investigate the extent to which this lungworm influences cane toad viability, we experimentally infected metamorph toads (the smallest and presumably most vulnerable terrestrial phase of the anuran life cycle) with the helminth. Infected toads exhibited reduced survival and growth rates, impaired locomotor performance (both speed and endurance), and reduced prey intake. In summary, R. pseudosphaerocephala can substantially reduce the viability of metamorph cane toads.

  11. Accumulation and depuration of trace metals in Southern Toads, Bufo Terrestris, exposed to coal combustion waste

    Energy Technology Data Exchange (ETDEWEB)

    Ward, C.; Hassan, S.; Mendonca, M. [Auburn University, Auburn, AL (United States). Dept. of Biological Science

    2009-02-15

    Accumulation and depuration of metals by an organism are underrepresented in the literature. We collected southern toads (Bufo terrestris) from coal by-product (ash)-contaminated and uncontaminated sites to examine metal concentrations over time. Toads were placed in four exposure regimes, then sacrificed periodically over a 5-month period, and whole-body metal levels were measured. Toads exposed to ash accumulated significant concentrations of metals. Metal concentrations changed throughout the experiment, and profiles of accumulation and depuration differed depending on the metal and exposure regime. Ash-exposed toads exhibited elevated levels of 11 of 18 metals measured. Increases ranged from 47.5% for Pb to more than 5000% for As. Eight of 18 metals did not change in control toads, while 10 of 18 metals decreased in toads removed from ash, ranging from -25% for Co to -96% for Tl. Seven metals that decreased in toads removed from ash did not change in control toads.

  12. Metabolic measures of male southern toads (Bufo terrestris) exposed to coal combustion waste

    Energy Technology Data Exchange (ETDEWEB)

    Ward, C.K.; Appel, A.G.; Mendonca, M.T. [Auburn University, Montgomery, AL (United States). Dept. of Biology

    2006-03-15

    Southern toads (Bufo terrestris) are found in coal fly ash collection basins associated with coal-burning electrical power plants. These basins contain large amounts of trace metals and organisms found in these basins are known to accumulate large quantities of metals. Studies on a variety of organisms exposed to trace metals found that they experience a significant increase in standard metabolic rate. We experimentally exposed southern toads to metal-contaminated sediment and food and measured changes in standard and exercise metabolic rates as well as changes in body, liver and muscle mass, blood glucose, and corticosterone. We found that toads exposed to trace metal contamination gained significantly less mass (18.3%) than control toads (31.3%) when food was limited and experienced significantly decreased RQ after exercise. However, contaminated toads did not experience changes in standard or exercise metabolic rates, plasma glucose levels, and hepatic or muscle percentage indices whether food was limited or not.

  13. Testes asymmetry of Bufo gargarizans in relation to body condition and age

    Directory of Open Access Journals (Sweden)

    Tong Lei Yu

    2015-12-01

    Full Text Available Testes asymmetry theory predicts that males in good condition or mature age may be able to develop larger degrees of directional asymmetry than males in poor condition or younger age. In this study, we tested the testes asymmetry theory in the Bufo gargarizans. We found that B. gargarizans has a significant directional asymmetry in testes mass, with left testis being significantly larger than right testis. Male body condition was correlated with relative testes mass and absolute testes asymmetry, but not correlated with relative testes asymmetry. Therefore, we suggested that males in good body condition have the higher ability of sperm competition than males in poor body condition. Additionally, male age was correlated with absolute testes asymmetry, but not correlated with relative testes mass and testes asymmetry, thus not supporting the hypothesis that males with a higher degree of directional asymmetry survive better.

  14. Bufo & Spallanzani e a paródia pós-modernista

    Directory of Open Access Journals (Sweden)

    Saulo Brandão

    2016-02-01

    Full Text Available O presente trabalho tem por objetivo investigar as considerações acerca da paródia e sua implicação na linha teórica pós-modernista, partindo das análises de Fredric Jameson e Linda Hutcheon, quando conceituando pastiche. Desse modo, nos propomos a fazer uma análise das paródias no romance Bufo & Spallanzani, de Rubem Fonseca, a partir da leitura de Ana Cristina T. de B. Carvalho (2013 que corrobora para sonegar a proposta de Jameson. Desse modo, procuraremos, no emaranhado de citações do romance, que remetem aos mais diversos campos da cultura, elementos que qualifiquem a característica paródica do romance, tendo por embasamento a contraproposta feita por Linda Hutcheon.

  15. The dynamics of venous return and response to hypervolemia in the toad, Bufo marinus (L.)

    Science.gov (United States)

    Killorn, Erin E; Toews, Daniel P

    2001-01-01

    Background Venous return from the posterior region of amphibians travels by either two renal portal veins to the kidney or a central abdominal vein that drains into the hepatic portal system. The relative proportions of blood flow in these vessels has never been measured nor has a modification of flow been determined when venous return increases by changes in blood volume during hypervolemia or during increased volume input from the posterior lymph hearts. Results Venous return from the posterior region of Bufo marinus was measured under resting conditions and in response to a systemic hypervolemia. Doppler flow probes were positioned on the renal portal and ventral abdominal veins, and flow was recorded as injections of artificial plasma equaling 100% of the animal's plasma volume were administered through the sciatic artery. Resting flow was found to be 5.54 ± 2.03 ml min-1 kg-1 in the paired renal portal veins, and 7.31 ± 0.89 ml min-1 kg-1 in the ventral abdominal vein. While renal portal flow was found to increase by a factor of 2.4 times during the first 10 min of hypervolemia, ventral abdominal flow only increased by a factor of 1.3. Conclusions Our results quantify the contribution to circulation from posterior venous return in the toad Bufo marinus. A preferential movement of excess fluid through the renal portal pathway was also demonstrated, supporting the possibility of water elimination via the renal portal circulation, especially during periods of high water influx into the animals. PMID:11696249

  16. Alimentación y fecundidad de Bufo variegatus (Anura: Bufonidae en Santa Cruz, Argentina

    Directory of Open Access Journals (Sweden)

    Rappi, Guillermina E.

    2000-04-01

    Full Text Available Se describe la alimentación de una población de Bufo variegatus procedente de la región de Lago del Desierto, provincia de Santa Cruz, Argentina. De los 11 ítems presa identificados, los más consumidos por los adultos (tanto machos como hembras fueron los coleópteros. En los machos la segunda categoría presa mas importante en la contribución a la dieta fueron los ácaros, mientras que en las hembras las hormigas y las larvas de insectos siguieron en importancia al consumo de coleópteros. En los especímenes juveniles, los ácaros fueron las presas más consumidas, quedando los coleópteros en segundo lugar en importancia relativa. Se demuestra la existencia de una correlación positiva significativa entre el volumen de las presas y el tamaño del depredador. Se aportan datos referentes a la fecundidad de B. variegatus y se comprueba la ausencia de correlación entre el tamaño de las hembras grávidas y el número de óvulos maduros. The diet of a population of Bufo variegatus from the region of Lago del Desierto, Santa Cruz province, Argentina, is described. Of the 11 prey items identified, Coleoptera was the most consumed prey both for males and females. In males, the second most important prey was Acarii, while in females they were the ants and insect larvae. Acarii was the most consumed prey for juveniles, followed by Coleoptera. A significant positive correlation was found between prey volume and predator body size. Fecundity information for B. variegwus is given, and a lack of correlation between snout-vent length of mature females and ovarian egg complement is demonstrated.

  17. Morphological and genetic differentiation among Chilean populations of Bufo spinulosus (Anura: Bufonidae) Diferenciación morfológica y genética entre poblaciones chilenas de Bufo spinulosus (Anura: Bufonidae)

    OpenAIRE

    Marco A. Méndez; Eduardo R. Soto; Claudio Correa; Alberto Veloso; Eliseo Vergara; Michel Sallaberry; Patricia Iturra

    2004-01-01

    Bufo spinulosus has a wide and fragmented range distribution in Chile (18° to 33° S) along altitudinal and latitudinal gradients. Genetic variation was estimated using RAPD (Random Amplified Polymorphic DNA) markers in 10 populations from northern and central Chile. Morphometric and genetic information was analyzed as a function of geographical origin. The correlation between genetic and morphometric differentiation was analyzed by the Mantel test. An increase in body size as a functi...

  18. Infestação de Amblyomma rotundatum (Koch (Acari, Ixodidae em sapos Bufo ictericus (Spix (Amphibia, Bufonidae: novo registro de hospedeiro Infestation of Amblyomma rotundatum (Koch (Acari, Ixodidae ticks on Bufo ictericus (Spix (Amphibia, Bufonidae: new host record

    Directory of Open Access Journals (Sweden)

    Germano Woehl Jr.

    2002-06-01

    Full Text Available Bufo ictericus Spix, 1824 toad population (N = 125 foraging in lighted areas in the Corupá Municipality, Santa Catarina State, was surveyed to evaluate the prevalence (percentage of infestation and the mean infestation intensity of Amblyomma rotundatum Koch, 1844 (Acari, Ixodidae ticks. The prevalence was of 19.2% and the mean infestation intensity was 7.4 ticks per infested toad. For the first time B. ictericus as host of A. rotundatum is reported.

  19. Synergy between glyphosate- and cypermethrin-based pesticides during acute exposures in tadpoles of the common South American toad Rhinella arenarum.

    Science.gov (United States)

    Brodeur, Julie Céline; Poliserpi, María Belén; D'Andrea, María Florencia; Sánchez, Marisol

    2014-10-01

    The herbicide glyphosate and the insecticide cypermethrin are key pesticides of modern management in soy and corn cultures. Although these pesticides are likely to co-occur in ephemeral ponds or aquatic systems supporting amphibian wildlife, the toxicological interactions prevailing in mixtures of these two pesticides have been little studied. The current study evaluated the toxicity of equitoxic and non-equitoxic binary mixtures of glyphosate- and cypermethrin-based pesticides to tadpoles of the common South American toad, Rhinella arenarum. Two different combinations of commercial products were tested: glyphosate Glifosato Atanor®+cypermethrin Xiper® and glyphosate Glifoglex®+cypermethrin Glextrin®. When tested individually, the formulations presented the following 96 h-LC50s: Glifosato Atanor® 19.4 mg ae L(-1) and Glifoglex 72.8 mg ae L(-1), Xiper® 6.8 mg L(-1) and Glextrin® 30.2 mg L(-1). Equitoxic and non-equitoxic mixtures were significantly synergic in both combinations of commercial products tested. The magnitude of the synergy (factor by which toxicity differed from concentration addition) was constant at around twofold for all tested proportions of the glyphosate Glifoglex®+cypermethrin Glextrin® mixture; whereas the magnitude of the synergy varied between 4 and 9 times in the glyphosate Glifosato Atanor®+cypermethrin Xiper® mixture. These results call for more research to be promptly undertaken in order to understand the mechanisms behind the synergy observed and to identify and quantify the extent of its environmental impacts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. EFFECTS OF CHRONIC CADMIUM EXPOSURE ON METAMORPHOSIS, SKELETAL DEVELOPMENT AND THYROID ENDOCRINE DISRUPTION IN CHINESE TOAD BUFO GARGARIZANS TADPOLES.

    Science.gov (United States)

    Sun, Nailiang; Wang, Hongyuan; Ju, Zongqi; Zhao, Hongfeng

    2017-08-11

    The study examined the effects of chronic cadmium exposure on metamorphosis, body size, thyroid gland, and skeletal development of Chinese toad (Bufo gargarizans) tadpoles. Tadpoles were exposed to cadmium concentrations at 0, 5, 10, 50,100 and 500 μg/L from Gonser stage 26 to Gosner stage 46 of completion of metamorphosis. Our results showed 100 and 500 μg/L cadmium concentrations increased mortality and decelerated metamorphosis rate. In addition, significant body size reduction at Gosner stage 42 was observed at 100 and 500 μg/L cadmium treatments (p Bufo gargarizans larvae. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Microsatellite analysis of the natterjack toad ( Bufo calamita ) in Denmark: populations are islands in a fragmented landscape

    DEFF Research Database (Denmark)

    Allentoft, Morten E.; Siegismund, Hans Redlef; Briggs, Lars

    2009-01-01

    The European natterjack toad (Bufo calamita) has declined rapidly in recent years, primarily due to loss of habitat, and in Denmark it is estimated that 50% of the isolated populations are lost each decade. To efficiently manage and conserve this species and its genetic diversity, knowledge...... in a highly fragmented gene pool. Future conservation management of this species is discussed in light of these results....

  2. [Aged skin and skin care].

    Science.gov (United States)

    Proksch, E

    2015-06-01

    Aged skin is the sum of chronological und UV-induced aging. Light-exposed skin is unattractive, with irregular pigmentation, roughness und scaliness. The skin is often dry and itches. The present paper provides an overview of diseases of aging skin and describes how to prevent or reduce disease by prophylactic and therapeutic skin care. Aged skin can develop into several skin diseases, e.g., different types of eczema and skin cancer. In the body folds we often find an irritant contact eczema caused by friction from skin to skin, sweating, and urinary and fecal incontinence. In the bedridden, bed sores can also develop. Furthermore, there is a delay in wound healing owing to old age. Use of adequate creams and ointments is very helpful in preventing and improving most skin diseases of mature skin. However, the knowledge of aged people and healthcare professionals about the importance of skin care is low. Older people are often unable to care for their skin because they are lacking the physical and mental ability. Healthcare professionals are not sufficiently trained about the value of proper skin care. Adequate studies on the role of skin care and selection of the correct preparation in various aged-related diseases are lacking.

  3. Skin Infections

    Science.gov (United States)

    ... Abscess Cellulitis Taking Care of Your Skin Abscess Impetigo Ringworm Cellulitis Should I Pop My Pimple? Tips for Taking Care of Your Skin Impetigo Paronychia Pityriasis Rosea Abscess Contact Us Print Resources ...

  4. Skin Aging

    Science.gov (United States)

    ... too. Sunlight is a major cause of skin aging. You can protect yourself by staying out of ... person has smoked. Many products claim to revitalize aging skin or reduce wrinkles, but the Food and ...

  5. Skin Dictionary

    Science.gov (United States)

    ... benefits Become a member DermCare Team Professionalism and ethics My account Member directory Publications JAAD JAAD Case ... SkinPAC State societies Scope of practice Truth in advertising Public and patients SPOT Skin Cancer™ Community programs & ...

  6. Sagging Skin

    Science.gov (United States)

    ... Hands Age Spots Aging Skin Birthmarks Burn Scars Cellulite Crow's Feet Droopy Eyelids Excess Fat Excessive Sweating ... Hands Age Spots Aging Skin Birthmarks Burn Scars Cellulite Crow's Feet Droopy Eyelids Excess Fat Excessive Sweating ...

  7. Skin Pigment

    Science.gov (United States)

    ... Summer Camp Tips for Kids With Asthma, Allergies Antioxidants: The Good Health Helpers As Stroke 'Liquefies' Brain ... Skin Cancer Additional Content Medical News Overview of Skin Pigment By Shinjita Das, MD, Instructor in Dermatology; ...

  8. Skin Cancer

    Science.gov (United States)

    Skin cancer is the most common form of cancer in the United States. The two most common types ... face, neck, hands, and arms. Another type of skin cancer, melanoma, is more dangerous but less common. Anyone ...

  9. Your Skin

    Science.gov (United States)

    ... and a little waterproofing. previous continue Skin Can Warm and Cool You Your skin can help if you're feeling too hot or too cold. Your blood ... you're ice-skating or sledding? When you're cold, your blood vessels keep your ... and keeping the warm blood away from the skin's surface. You might ...

  10. Genetic variability in geographic populations of the natterjack toad (Bufo calamita)

    Science.gov (United States)

    Oromi, N; Richter-Boix, A; Sanuy, D; Fibla, J

    2012-01-01

    Across altitudinal and latitudinal gradients, the proportion of suitable habitats varies, influencing the individual dispersal that ultimately can produce differentiation among populations. The natterjack toad (Bufo calamita) is distributed across a wide geographic range that qualifies the species as interesting for a geographic analysis of its genetic variability. Five populations of B. calamita in the Sierra de Gredos (Spain) were studied in an altitudinal gradient ranging from 750 to 2270 m using microsatellite markers. In addition, we analyzed the latitudinal genetic variation in B. calamita within a global European distribution using genetic diversity parameters (mean number of alleles per locus [Ma] and expected heterozygosity [HE]) obtained from our results and those published in the literature. The low level of genetic differentiation found between populations of B. calamita (Fst ranging from 0.0115 to 0.1018) and the decreases in genetic diversity with altitude (Ma from 13.6 to 8.3, HE from 0.82 to 0.74) can be interpreted by the combined effects of discontinuous habitat, produced mainly by the high slopes barriers and geographic distance. In the latitudinal gradient, genetic diversity decreases from south to north as a consequence of the colonization of the species from the Pleistocene refugium. We conclude that the genetic variability in B. calamita along its wide altitudinal and latitudinal geographic distribution mainly reflects the colonization history of the species after the last glacial period. PMID:22957202

  11. Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis

    Science.gov (United States)

    Sakr, S. A.; Badawy, G. M.; El-Borm, H. T.

    2014-01-01

    The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55) and postmetamorphic (66) stages. The metamorphic stages (60 and 63) displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled. PMID:24715821

  12. Measuring Energetics and Behaviour Using Accelerometry in Cane Toads Bufo marinus

    Science.gov (United States)

    Halsey, Lewis G.; White, Craig R.

    2010-01-01

    Cane toads Bufo marinus were introduced to Australia as a control agent but now have a rapidly progressing invasion front and damage new habitats they enter. Predictive models that can give expansion rates as functions of energy supply and feeding ground distribution could help to maximise control efficiency but to date no study has measured rates of field energy expenditure in an amphibian. In the present study we used the accelerometry technique to generate behavioural time budgets and, through the derivation of ODBA (overall dynamic body acceleration), to obtain estimates of energetics in free ranging cane toads. This represents the first time that accelerometers have been used to not only quantify the behaviour of animals but also assign to those behaviours rates of energy expenditure. Firstly, laboratory calibrations between ODBA and metabolic rate were obtained and used to generate a common prediction equation for the subject toads (R2 = 0.74). Furthermore, acceleration data recorded during different behaviours was studied to ascertain threshold values for objectively defining behaviour categories. Importantly, while subsequent accelerometer field deployments were relatively short they agreed with previous studies on the proportion of time that cane toads locomote yet suggest that the metabolic rate of cane toads in the wild may sometimes be considerably higher than might be assumed based on data for other species. PMID:20422048

  13. [Effects of different stocking density and diet on development of Bufo gargarizans tadpoles].

    Science.gov (United States)

    Li, Jun-de; Zhao, Qun; Kang, Yan; Gao, Bo; Li, Deng-Lin; Yang, Yan; Huang, Lu-Qi

    2016-03-01

    The effects of four different stocking densities and five different diets on the growth of Bufo gargarizans tadpoles were studied to determine the optimum stocking density and diet. For stocking density experiment, the tadpoles were fed respectively at different density of 200, 500, 1 000 and 2 000 tadpoles per square meter. For diet experiment, the tadpoles were divided into five groups fed respectively with five different diets. The body weight, snout-vent length and tail length were measured every seven days, and mortality was recorded. The results showed that: the survival rates of tadpole before metamorphosis and after metamorphosis were from 68.7% to 96.3% and from 5.7% to 36.0%, respectively; the optimum stocking density is 1 000 tadpoles per square meter for the stocking density had no effect on the survival rate of tadpole before metamorphosis, and the tadpoles had the relative large body weight and survival numbers in 1000 tadpoles per square meter; the diet Ⅱ(37.9% crude protein and 5.7% crude fat), Ⅳ (25.1% crude protein and 4.0% crude fat), and Ⅴ (egg yolk) were all the optimum diets for the diet had no effect on the survival rate of tadpole before metamorphosis and the tadpoles fed with three kinds of diet above had relatively large body weight, and one of these three diets based on their availability and cost should be adopted during breeding period. Copyright© by the Chinese Pharmaceutical Association.

  14. Effect of Cortisol on Plasma Lactate Levels following Cortisolinduced Hyperglycaemia in Common African Toad, Bufo regularis.

    Science.gov (United States)

    Isehunwa, G O; Oladun, O T; Akpan, J E; Alada, A R A

    2017-06-30

    Previous studies in man have shown that cortisol induces hyperglycemia through gluconeogenesis. However,the metabolic substrates involved in cortisol-induced hyperglycemia and the role of adrenergic receptors in lactate productionin toads have not been well studied. This study investigated the effects of adrenergic receptor blockers in cortisol-inducedhyperglycemia and blood lactate levels in the common African toad (Bufo regularis). Each toad was fasted and anaesthetizedwith sodium thiopentone given intraperitoneally (50mg/kg/i.p). The animals (control) received 0.7% amphibian saline whileanimals (untreated) received cortisol intravenously (50µg/kg/i.v). In pre-treatment groups, animals received propanolol (0.5mg/kg/i.v), prazosin (0.2 mg/kg/i.v) and combination of propanolol (0.5mg/kg/i.v) and prazosin (0.2 mg/kg/i.v) respectivelyfollowed by administration of cortisol 50µg/kg/i.v. Thereafter, blood samples were collected for estimation of glucose andlactate using the modified glucose oxidase method and colorimetric method respectively. Cortisol caused significant increase in blood glucose level ((pbufo regularis. The betaadrenergic receptors are involved in the use of lactate to induce cortisol hyperglycemia in the Common African toad Buforegularis.

  15. Hematotoxic and biochemical effects of UVA on the Egyptian toad (Bufo regularis).

    Science.gov (United States)

    Sayed, Alaa El-Din H

    2016-01-01

    To study the adverse impacts of ultraviolet radiation-A (UVA 320-400 nm) on some hematological and biochemical parameters of Bufo regularis was considered. Samples were classified into four groups: (i) Control; (ii) ultraviolet radiation (UVR)-treated group (for 3 days/for 15 min/day); (iii) UVR-treated group (for 3 days/for 30 min/day); and (iv) (for 3 days/for 60 min/day). The destructive effects of UVA radiation was evaluated by red blood cells (RBC) count, hemoglobin content (Hb), hematocrite (Ht), erythrocytic indices, white blood cells (WBC) count, total protein, glucose, aspartic amino transferase (AST), alanine amino transferase (ALT), alkaline phosphatase (ALP), lactate dehyderogenase (LDH), glucose-6-phosphate dehyderogenase (G6PDH) and total bilribuin. No mortality was observed. However, some physiological effects after the exposure to UVA were reported. The UVA-induced malformations recorded in the red blood cells included crenated cells (Cr), Acanthocytes (Ac), tear drop-like cells (Tr) and sickle cells (Sk). The present study revealed the exposure to UVA from 15-60 min/day for three days could promote several biochemical and physiological disturbances as well as some changes in RBC.

  16. Chronic Effects of Fluoride Exposure on Growth, Metamorphosis, and Skeleton Development in Bufo gargarizans Larvae.

    Science.gov (United States)

    Chai, Lihong; Wang, Hongyuan; Zhao, Hongfeng; Dong, Suiming

    2017-04-01

    Bufo gargarizans tadpoles were chronically exposed to waterborne fluoride at measured concentrations ranging from 0.4 to 61.2 mg F-/L for 70 days from Gosner stage 26 to completion of metamorphosis. The chronic exposure caused a concentration-dependent mortality in all tested fluoride concentrations. Total length, snout-to-vent length (SVL), body mass, and developmental stage of tadpoles were significantly inhibited at 42.6 mg F-/L. In addition, significant metamorphic delay and increase in size at completion of metamorphosis occurred after exposure to 19.8 mg F-/L. Moreover, 19.8 mg F-/L suppressed the bone mineralization of larvae at completion of metamorphosis. However, the bone mineralization could be enhanced by 4.1 mg F-/L. In conclusion, our results suggested that the presence of high concentrations of fluoride could increase mortality risk, delay metamorphosis, and suppress skeletal ossification in B. gargarizans larvae.

  17. Genetic comparison of water molds from embryos of amphibians Rana cascadae, Bufo boreas and Pseudacris regilla.

    Science.gov (United States)

    Ault, Kori K; Johnson, James E; Pinkart, Holly C; Wagner, R Steven

    2012-06-13

    Water molds that cause the disease saprolegniasis have been implicated in widespread mortality of amphibian embryos. However, because of the limitations of traditional identification methods, water mold species involved in die-offs or utilized in ecological studies often remain unidentified or identified only as Saprolegnia ferax. Furthermore, water mold taxonomy requires revision, so very distinct organisms may all be called S. ferax. Recent DNA-based studies indicate that the diversity of water molds infecting amphibian embryos is significantly higher than what was previously known, but these studies rely on culture methods, which may be biased towards taxa that grow best under laboratory conditions. In this study, total embryo-associated DNA was extracted from 3 amphibian species in a pond in central Washington, USA. The internal transcribed spacer (ITS) region of DNA was amplified with primers capable of amplifying a broad array of eukaryotic microorgansisms, and was used to construct clone libraries. Individual clones were sequenced and relationships among newly recovered sequences and previously studied taxa were analyzed using phylogenetics. These methods recovered several new taxa in association with amphibian embryos. Samples grouped into 11 distinct phylotypes with ITS sequence differences ranging from 4 to 28%. The water mold communities recovered differed among Rana cascadae, Bufo boreas, and Pseudacris regilla egg masses. Furthermore, the diversity of water molds increased as egg masses aged, and members comprising this diversity changed over time.

  18. Quantifying Bufo boreas connectivity in Yellowstone National Park with landscape genetics.

    Science.gov (United States)

    Murphy, Melanie A; Evans, Jeffrey S; Storfer, Andrew

    2010-01-01

    A major objective of ecology is to understand how ecological processes limit population connectivity and species' distributions. By spatially quantifying ecological components driving functional connectivity, we can understand why some locally suitable habitats are unoccupied, resulting in observed discontinuities in distribution. However, estimating connectivity may be difficult due to population stochasticity and violations of assumptions of parametric statistics. To address these issues, we present a novel application of Random Forests to landscape genetic data. We address the effects of three key ecological components on Bufo boreas connectivity in Yellowstone National Park: ecological process, scale, and hierarchical organization. Habitat permeability, topographic morphology, and temperature-moisture regime are all significant ecological processes associated with B. boreas connectivity. Connectivity was influenced by growing-season precipitation, 1988 Yellowstone fires, cover, temperature, impervious surfaces (roads and development), and topographic complexity (56% variation explained). We found that habitat permeability generally operates on fine scales, while topographic morphology and temperature-moisture regime operate across multiple scales, thus demonstrating the importance of cross-scale analysis for ecological interpretation. In a hierarchical analysis, we were able to explain more variation within genetic clusters as identified using Structure (a Bayesian algorithm) (74%; dispersal cover, growing-season precipitation, impervious surfaces) as opposed to between genetic clusters (45%; ridgelines, hot, dry slopes, length of hot season, and annual precipitation). Finally, the analytical methods we developed are powerful and can be applied to any species or system with appropriate landscape and genetic data.

  19. Membranes during yolk-platelet development in oocytes of the toad Bufo marinus.

    Science.gov (United States)

    Richter, H -P

    1987-09-01

    Oocytes of the toad Bufo marinus have been studied by means of thin section and particularly freeze-fracture electron microscopy to characterize the cytoplasmic membranes around the yolk organelle, and the storage of yolk material in precursors and platelets. This appears to be a previously unknown type of yolk-platelet formation. During yolk-organelle development from the primordial precursor to the bi-partite fully grown yolk platelet, numerous lipoid droplets are attached to the periphery of the platelet, indicating an intense uptake of lipids. As is typical for amphibians, the fully grown yolk platelet has a crystalline internum covered by a dense osmiophilic externum, and the whole organelle is enveloped by a plasma membrane that shows no direct connection or fusion with endocytotic vesicles. The yolk membrane exhibits few intramembraneous particles (IMPs) at the core areas and some more where it borders fields of lipoid droplets. Here the IMPs show a net-like arrangement in the furrows between adjacent droplets.

  20. Assessment of pollution in road runoff using a Bufo viridis biological assay

    Energy Technology Data Exchange (ETDEWEB)

    Dorchin, A., E-mail: adorchin@campus.haifa.ac.i [Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905 (Israel); Shanas, U., E-mail: shanas@research.haifa.ac.i [Department of Evolutionary and Environmental Biology, Faculty of Natural Sciences, University of Haifa, Mount Carmel, Haifa 31905 (Israel); Department of Biology, Faculty of Natural sciences, University of Haifa - Oranim, Tiv' on 36006 (Israel)

    2010-12-15

    Road runoff is a major source of environmental pollution, significantly threatening nearby aquatic habitats. Chemical analyses indicate high pollutant concentrations in the road's 'first flush', but bioassays are more advantageous for addressing the cumulative effects of the numerous pollutants within the runoff. We used Bufo viridis embryos and larvae to assess the toxicity of road runoff from two major highways in Israel. We show, for the first time, that exposure to midseason runoff not only has an adverse effect on growth and development rates of B. viridis larvae but can also lead to increased rates of morphological deformations. Seasonal first flushes, despite having higher metal concentrations, did not adversely affect the toad larvae, apparently due to a counter effect of organic matter that potentially served as a supplementary energy resource. Road runoff can be a major cause for a qualitative decrease in the quality of aquatic habitats threatening amphibians in Israel. - Highway runoff has detrimental effects on the development of B. viridis larvae.

  1. Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis

    Directory of Open Access Journals (Sweden)

    S. A. Sakr

    2014-01-01

    Full Text Available The ontogenetic development of the small intestine of the toad Bufo regularis was investigated using twofold approaches, namely, ultrastructural and molecular. The former has been done using transmission electron microscope and utilizing the developmental stages 42, 50, 55, 60, 63, and 66. The most prominent ultrastructural changes were recorded at stage 60 and were more evident at stage 63. These included the appearance of apoptotic bodies/nuclei within the larval epithelium, the presence of macrophages, swollen mitochondria, distorted rough endoplasmic reticulum, chromatin condensation, and irregular nuclear envelop, and the presence of large vacuoles and lysosomes. The molecular investigation involved examining DNA content and fragmentation. The results showed that the DNA content decreased significantly during the metamorphic stages 60 and 63 compared with both larval (50 and 55 and postmetamorphic (66 stages. The metamorphic stages (60 and 63 displayed extensive DNA laddering compared with stages 50, 55, and 66. The percentage of DNA damage was 0.00%, 12.91%, 57.26%, 45.48%, and 4.43% for the developmental stages 50, 55, 60, 63, and 66, respectively. In conclusion, the recorded remodeling of the small intestine represents a model for clarifying the mechanism whereby cell death and proliferation are controlled.

  2. Measuring energetics and behaviour using accelerometry in cane toads Bufo marinus.

    Directory of Open Access Journals (Sweden)

    Lewis G Halsey

    Full Text Available Cane toads Bufo marinus were introduced to Australia as a control agent but now have a rapidly progressing invasion front and damage new habitats they enter. Predictive models that can give expansion rates as functions of energy supply and feeding ground distribution could help to maximise control efficiency but to date no study has measured rates of field energy expenditure in an amphibian. In the present study we used the accelerometry technique to generate behavioural time budgets and, through the derivation of ODBA (overall dynamic body acceleration, to obtain estimates of energetics in free ranging cane toads. This represents the first time that accelerometers have been used to not only quantify the behaviour of animals but also assign to those behaviours rates of energy expenditure. Firstly, laboratory calibrations between ODBA and metabolic rate were obtained and used to generate a common prediction equation for the subject toads (R(2 = 0.74. Furthermore, acceleration data recorded during different behaviours was studied to ascertain threshold values for objectively defining behaviour categories. Importantly, while subsequent accelerometer field deployments were relatively short they agreed with previous studies on the proportion of time that cane toads locomote yet suggest that the metabolic rate of cane toads in the wild may sometimes be considerably higher than might be assumed based on data for other species.

  3. Effect of gibberellin-A3 on metamorphosis in the Egyptian toad Bufo regularis

    Directory of Open Access Journals (Sweden)

    Saber A. Sakr

    2012-05-01

    Full Text Available The present study was carried out to study the effect of gibberellin-A3 on the metamorphosis of the Egyptian toad Bufo regularis. Samples of B. regularis were collected from Shebin El-Kom, Menoufia Governorate during the breeding season and kept in aquaria with little water till spawning, fertilized eggs are divided into 2 groups of 200 eggs each. The 1st group was treated with 5 ppm of gibberellin-A3 (Berelex 3 days/week for the period of metamorphosis. The second group was left untreated under the same environmental conditions and considered as a control. Hatchability of the eggs in each group was recorded. External lengths of the total body, hind limbs and the tail were measured. As a measure of apoptotic DNA fragmentation, the presence of DNA ladder was determined. The results showed that out of 200 eggs 47.5% were hatched in the control group and 76.5% were hatched in gibberellin-A3 treated group. The average duration of metamorphosis was 60 days and 52 days in the control and treated groups, respectively. There was an increase in the total length of the hind limbs of the treated tadpole as compared with the control throughout the experimental periods. DNA isolated from control and tadpoles treated with gibberellin-A3 showed degradation into oligonucleotide fragments forming a clear laddering pattern of apoptosis, but the treated tadpoles showed an increase of DNA fragmentation.

  4. Comparative study on the tongue of Bufo regularis and Chalcides ocellatus in relation to their habitats

    Directory of Open Access Journals (Sweden)

    E.H. Elsheikh

    2013-05-01

    Full Text Available The present study investigated the structure of the tongue of the toad, Bufo regularis and the lizard, Chalcides ocellatus. They have different feeding habits and live in different habitats. The tongue of the toad contains two types of lingual papillae; fungiform papillae and filiform papillae. The fungiform papillae are usually scattered among the filiform papillae and are believed to function in gustation and in the secretion of salivary fluid. Scanning electron microscopical studies revealed that no ciliated cells were observed on the surface of the filiform papillae or in the surrounding area of the sensory disc. In C. ocellatus the tip of the tongue is bifurcated and keratinized. The dorsal surface of the tongue is covered with several types of papillae; irregular, scale and ridge-shaped. Taste buds were present in the epithelium of the tongue. The lingual glands consist of mucous cells that form crypt-like invaginations between papillae. The present study revealed that there is a marked correlation between the structure of the tongue of both B. regularis and C. ocellatus and habitats and feeding mechanism of the two species.

  5. Skin Diseases: Skin Health and Skin Diseases

    Science.gov (United States)

    ... a serious case, you might need medical help. Impetigo —A skin infection caused by bacteria. Usually the ... and form a thick crust. You can treat impetigo with antibiotics. Melanoma © 2008 Logical Images, Inc. Melanoma — ...

  6. New species of Rhabdias (Nematoda: Rhabdiasidae) from Bufo occidentalis (Anura: Bufonidae) from Sierra Madre del Sur, Mexico.

    Science.gov (United States)

    Martínez-Salazar, Elizabeth A; León-Règagnon, Virginia

    2007-10-01

    Rhabdias kuzmini n. sp., a parasite of the lungs of Bufo occidentalis, is described and illustrated. This Mexican taxon differs from the related species in the genus by the possession of 4 lips (2 subdorsal and 2 subventral) and 2 lateral pseudolabia, corpus not inflated, a larger barrel-shaped buccal capsule, equatorial vulva, and the presence of a slightly swollen cuticle in the anterior and posterior ends of the body. This is the 16th species described in the Neotropical Realm and the first species of Rhabdias described from endemic anurans in México.

  7. Skin abscess

    Science.gov (United States)

    ... can help identify the cause of the infection. Treatment You can apply moist heat (such as warm compresses) to help the abscess ... if you develop new symptoms during or after treatment of a skin abscess. Prevention ... the skin around minor wounds clean and dry to prevent infection. Call your provider if you ...

  8. CRYPTIC NEOGENE VICARIANCE AND QUATERNARY DISPERSAL OF THE RED-SPOTTED TOAD (BUFO PUNCTATUS) INSIGHTS ON THE EVOLUTION OF NORTH AMERICAN WARM DESERT BIOTAS

    Science.gov (United States)

    We define the geographic distributions of embedded evolutionary mitochondrial DNA (mtDNA) lineages (clades) within a broadly distributed, arid- dwelling toad, Bufo punctatus, and evaluate these patterns as they relate to hypothesized vicariant events leading to the formation of b...

  9. On the presence of Bufo nasicus Werner in Guiana, with a redescription of the species on the basis of recently collected material

    NARCIS (Netherlands)

    Hoogmoed, M.S.

    1977-01-01

    During research on material recently collected in Guyana and in Venezuelan Guiana, several specimens of the rare toad Bufo nasicus Werner, thus far only known from the holotype without known origin, were discovered. On the basis of this material the species is redescribed and some notes on its

  10. Helmintos parásitos de anfibios: Dos Especies de Nemátodos parásitos de Bufo spinulosus trifolium (Tschudi

    Directory of Open Access Journals (Sweden)

    Asucena Naupay

    2014-06-01

    Full Text Available En el presente trabajo sobre los helmintos que parasitan a Bufo spinulosus trifolium (Tschudi de la localidad de Huánuco, se presentan dos especies conocidas para la ciencia pero una de ellas nueva para el Perú.

  11. Effects of copper on growth, metamorphosis and endocrine disruption of Bufo gargarizans larvae.

    Science.gov (United States)

    Wang, Chao; Liang, Gang; Chai, Lihong; Wang, Hongyuan

    2016-01-01

    Chinese toad (Bufo gargarizans) tadpoles were exposed to copper (1, 6.4, 32 and 64μgL(-1) copper) from the beginning of larval period through completion of metamorphosis. We examined the effects of chronic copper exposure on mortality, growth, time to metamorphosis, tail resorption time, body size at the metamorphic climax (Gs 42) and completion of metamorphosis (Gs 46) and thyroid gland histology. In addition, type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. Our result showed that 6.4-64μgL(-1) copper concentration increased the mortality and inhibited the growth of B. gargarizans tadpoles. In addition, significant reduction in size at Gs 42 and a time delay to Gs 42 were observed at 6.4-64μgL(-1) copper treatments. Moreover, histological examinations have clearly revealed that 64μgL(-1) copper caused follicular cell hyperplasia in thyroid gland. According to real-time PCR results, exposure to 32 and 64μgL(-1) copper significantly up-regulated mRNA expression of Dio3, but down-regulated mRNA expression of TRα and TRβ mRNA level. We concluded that copper delayed amphibian metamorphosis through changing mRNA expression of Dio3, TRα and TRβ, which suggests that copper might have the endocrine-disrupting effect. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Ranking Landscape Development Scenarios Affecting Natterjack Toad (Bufo calamita) Population Dynamics in Central Poland

    Science.gov (United States)

    Franz, Kamila W.; Romanowski, Jerzy; Johst, Karin; Grimm, Volker

    2013-01-01

    When data are limited it is difficult for conservation managers to assess alternative management scenarios and make decisions. The natterjack toad (Bufo calamita) is declining at the edges of its distribution range in Europe and little is known about its current distribution and abundance in Poland. Although different landscape management plans for central Poland exist, it is unclear to what extent they impact this species. Based on these plans, we investigated how four alternative landscape development scenarios would affect the total carrying capacity and population dynamics of the natterjack toad. To facilitate decision-making, we first ranked the scenarios according to their total carrying capacity. We used the software RAMAS GIS to determine the size and location of habitat patches in the landscape. The estimated carrying capacities were very similar for each scenario, and clear ranking was not possible. Only the reforestation scenario showed a marked loss in carrying capacity. We therefore simulated metapopulation dynamics with RAMAS taking into account dynamical processes such as reproduction and dispersal and ranked the scenarios according to the resulting species abundance. In this case, we could clearly rank the development scenarios. We identified road mortality of adults as a key process governing the dynamics and separating the different scenarios. The renaturalisation scenario clearly ranked highest due to its decreased road mortality. Taken together our results suggest that road infrastructure development might be much more important for natterjack toad conservation than changes in the amount of habitat in the semi-natural river valley. We gained these insights by considering both the resulting metapopulation structure and dynamics in the form of a PVA. We conclude that the consideration of dynamic processes in amphibian conservation management may be indispensable for ranking management scenarios. PMID:23734223

  13. Multi-Level Effects of Low Dose Rate Ionizing Radiation on Southern Toad, Anaxyrus [Bufo] terrestris

    Science.gov (United States)

    Stark, Karolina; Scott, David E.; Tsyusko, Olga; Coughlin, Daniel P.; Hinton, Thomas G.

    2015-01-01

    Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development –embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of 137Cs at 0.13, 2.4, 21, and 222 mGy d-1, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay) in red blood cells at a dose rate of 21 mGy d-1 and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae. PMID:25927361

  14. Effects of fluoride on morphology, growth, development, and thyroid hormone of Chinese toad (Bufo gargarizans) embryos.

    Science.gov (United States)

    Zhang, Yuhui; Xie, Lei; Li, Xinyi; Chai, Lihong; Chen, Mengxing; Kong, Xiaojing; Wang, Qingqing; Liu, Jingfei; Zhi, Lijuan; Yang, Chang; Wang, Hongyuan

    2017-10-12

    Excessive fluoride in natural water ecosystem has the potential to detrimentally affect amphibians, but little is known of such effects or underlying mechanisms in Bufo gargarizans embryos. In the present study, the effects of fluoride exposure on B. gargarizans embryos were investigated. First, fluoride teratogenic experiment showed that the 9 days EC50 of fluoride on B. gargarizans embryos was 177.62 mg/L. Then, we studied the sublethal effects of fluoride on B. gargarizans embryos at control, 0.7, 4.1, 19.6, 41.9, and 62.7 mg/L fluoride concentration. Malformation, growth, and development of embryos were monitored, and type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were measured. Our results showed the morphological malformations, such as tail curvature (lordosis), edema, cuticularized ciliated cells, and hyperplasia were occurred during fluoride exposure. Growth and development were all inhibited at 19.5, 41.9, and 62.7 mg/L fluoride-treated groups after 9 days' exposure. According to real-time PCR results, exposure to fluoride upregulated Dio3 and TRβ mRNA expression and downregulated Dio2 and TRα mRNA level. All above indicated that excessive fluoride could induce morphology malformations, inhibit embryonic growth and development, and disrupt the normal function of maternal thyroid hormone in B. gargarizans embryos. Environ. Mol. Mutagen., 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Chronic effects of triclosan on embryonic development of Chinese toad, Bufo gargarizans.

    Science.gov (United States)

    Chai, Lihong; Wang, Hongyuan; Zhao, Hongfeng; Deng, Hongzhang

    2016-10-01

    Triclosan (TCS) is commonly used worldwide in a range of personal care and sanitizing products. The aim of this study was to evaluate potential effects of TCS exposure on embryonic development of Bufo gargarizans, an endemic frog species in China. Standard Gosner stage 3 B. gargarizans embryos were exposed to 10 ~ 150 μg/L TCS during embryogenesis. Survival, total length, weight, developmental stage, duration of different embryo stages, malformation, and type II and III deiodinase (D2 and D3) expression were measured. Inhibitory effects on embryo developmental stage, total length and weight were found at 30 ~ 150 μg/L TCS. Moreover, the duration of embryonic development was increased at gastrula, neural, circulation, and operculum development stage in TCS-treated groups. In addition, TCS exposure induced morphological malformations in B. gargarizans embryos, which are characterized by hyperplasia, abdominal edema, and axial flexures. Furthermore, our results showed that the expression of D2 in embryos was probably down-regulated at 60 and 150 μg/L TCS, but its spatial expression patterns was not affected by TCS. In summary, our study suggested that TCS exposure not only resulted in delayed growth and development but also caused teratogenic effects in B. gargarizans embryos, and the developmental effects of TCS at high concentrations may be associated with disruption of THs homeostasis. Although further studies are necessary, the present findings could provide a basis for understanding on harmful effects and the potential mechanisms of TCS in amphibian embryos.

  16. Molecular cloning and analysis of Myc modulator 1 (Mm-1 from Bufo gargarizans (Amphibia: Anura

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    Ning Wang

    2010-02-01

    Full Text Available The protein of Myc modulator 1 (Mm-1 has been reported to repress the transcriptional activity of the proto-oncogene c-Myc in humans. Moreover, it was shown to be the subunit 5 of human prefoldin (PFD. So far, this gene and its homologs have been isolated and sequenced in many organisms, such as mammals and fish, but has not been sequenced for any amphibian or reptile. In order to better understand the function and evolution of Mm-1, we isolated a full-length Mm-1 cDNA (BgMm-1, GenBank accession no. EF211947 from Bufo gargarizans (Cantor, 1842 using RACE (rapid amplification of cDNA ends methods. Mm-1 in B. gargarizans is 755 bp long, comprising an open reading frame (ORF of 459 bp encoding 152 amino acids. The amino acid sequence had a prefoldin α-like domain, partially including a typical putative leucine zipper motif. BgMm-1 showed high similarity to its homolog of Mus musculus Linnaeus, 1758 (82% and Homo sapiens Linnaeus, 1758 MM-1 isoform a (81% at the amino acid level. The protein secondary structure modeled with the SWISS MODEL server revealed that there were two α-helices and four b-strands in BgMm-1 as its human orthologue, and both proteins belonged to the a class of PFD family. The phylogenetic relationships of Mm-1s from lower archaea to high mammals was consistent with the evolution of species, meanwhile the cluster result was consistent with the multiple alignment and the sequence identity analysis. RT-PCR (reverse transcriptase-polymerase chain reaction analysis demonstrated that BgMm-1 expressed widely in ten tissues of adult toad. These results can be helpful for the further investigation on the evolution of Mm-1.

  17. Multi-Level Effects of Low Dose Rate Ionizing Radiation on Southern Toad, Anaxyrus [Bufo] terrestris.

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    Karolina Stark

    Full Text Available Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later, to four low dose rates of 137Cs at 0.13, 2.4, 21, and 222 mGy d-1, resulting in total doses up to 15.8 Gy. Radiation treatments did not affect hatching success of embryos, larval survival, or the length of the larval period. The individual family variation in hatching success of embryos was larger than the radiation response. In contrast, newly metamorphosed individuals from the higher dose-rate treatments had higher mass and mass/length body indices, a measure which may relate to higher post-metamorphic survival. The increased mass and index at higher dose rates may indicate that the chronic, low dose rate radiation exposures triggered secondary responses. Additionally, the increases in growth were linked to a decrease in DNA damage (as measured by the Comet Assay in red blood cells at a dose rate of 21 mGy d-1 and a total dose of 1.1 Gy. In conclusion, the complex effects of low dose rates of ionizing radiation may trigger growth and cellular repair mechanisms in amphibian larvae.

  18. Modelling the extinction risk of isolated populations of natterjack toad Bufo calamita

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    F. Meyer

    2001-09-01

    Full Text Available Many local populations of the natterjack toad Bufo calamita in Germany are endangered. Due to the fragmentation and destruction of natural habitats by man, toads have often been forced to switch to secondary habitats. The permanent existence of these habitats is uncertain. Habitat and area requirements have been investigated in various parts of Germany in recent years. Our study uses field observations from sites in Halle (Saxony-Anhalt and List (Schleswig-Holstein as a basis for analyses of the population dynamics under different environmental conditions. Deterministic trends of these populations are calculated with the help of a Leslie matrix consisting of average parameters for mortality and reproduction. For a more thorough analysis we use a stochastic simulation model in order to assess survival probabilities of local toad populations. This model also takes into account environmental fluctuations affecting mortality and reproduction. Using scenarios from different locations, a sensitivity analysis of the parameters indicates which management options are the most promising to preserve a population. Our results indicate that the mortality rates of juveniles and the availability of spawning ground have the greatest influence on a population’s survival. Consequently, habitat management should focus on these aspects. In addition, we investigate the risk of extinction for different reproductive strategies. Natterjack toad populations observed in the field actually follow a strategy with three breeding periods. We find that this strategy supports the survival of the population better than strategies with less periods, which are more likely to result in a complete breeding failure during one season.

  19. Ranking landscape development scenarios affecting natterjack toad (Bufo calamita population dynamics in Central Poland.

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    Kamila W Franz

    Full Text Available When data are limited it is difficult for conservation managers to assess alternative management scenarios and make decisions. The natterjack toad (Bufo calamita is declining at the edges of its distribution range in Europe and little is known about its current distribution and abundance in Poland. Although different landscape management plans for central Poland exist, it is unclear to what extent they impact this species. Based on these plans, we investigated how four alternative landscape development scenarios would affect the total carrying capacity and population dynamics of the natterjack toad. To facilitate decision-making, we first ranked the scenarios according to their total carrying capacity. We used the software RAMAS GIS to determine the size and location of habitat patches in the landscape. The estimated carrying capacities were very similar for each scenario, and clear ranking was not possible. Only the reforestation scenario showed a marked loss in carrying capacity. We therefore simulated metapopulation dynamics with RAMAS taking into account dynamical processes such as reproduction and dispersal and ranked the scenarios according to the resulting species abundance. In this case, we could clearly rank the development scenarios. We identified road mortality of adults as a key process governing the dynamics and separating the different scenarios. The renaturalisation scenario clearly ranked highest due to its decreased road mortality. Taken together our results suggest that road infrastructure development might be much more important for natterjack toad conservation than changes in the amount of habitat in the semi-natural river valley. We gained these insights by considering both the resulting metapopulation structure and dynamics in the form of a PVA. We conclude that the consideration of dynamic processes in amphibian conservation management may be indispensable for ranking management scenarios.

  20. The ecological impact of invasive cane toads (Bufo marinus) in Australia.

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    Shine, Richard

    2010-09-01

    Although invasive species are viewed as major threats to ecosystems worldwide, few such species have been studied in enough detail to identify the pathways, magnitudes, and timescales of their impact on native fauna. One of the most intensively studied invasive taxa in this respect is the cane toad (Bufo marinus), which was introduced to Australia in 1935. A review of these studies suggests that a single pathway-lethal toxic ingestion of toads by frog-eating predators-is the major mechanism of impact, but that the magnitude of impact varies dramatically among predator taxa, as well as through space and time. Populations of large predators (e.g., varanid and scincid lizards, elapid snakes, freshwater crocodiles, and dasyurid marsupials) may be imperilled by toad invasion, but impacts vary spatially even within the same predator species. Some of the taxa severely impacted by toad invasion recover within a few decades, via aversion learning and longer-term adaptive changes. No native species have gone extinct as a result of toad invasion, and many native taxa widely imagined to be at risk are not affected, largely as a result of their physiological ability to tolerate toad toxins (e.g., as found in many birds and rodents), as well as the reluctance of many native anuran-eating predators to consume toads, either innately or as a learned response. Indirect effects of cane toads as mediated through trophic webs are likely as important as direct effects, but they are more difficult to study. Overall, some Australian native species (mostly large predators) have declined due to cane toads; others, especially species formerly consumed by those predators, have benefited. For yet others, effects have been minor or have been mediated indirectly rather than through direct interactions with the invasive toads. Factors that increase a predator's vulnerability to toad invasion include habitat overlap with toads, anurophagy, large body size, inability to develop rapid behavioral

  1. Hormonal priming, induction of ovulation and in-vitro fertilization of the endangered Wyoming toad (Bufo baxteri)

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    Browne, Robert K; Seratt, Jessica; Vance, Carrie; Kouba, Andrew

    2006-01-01

    The endangered Wyoming toad (Bufo baxteri) is the subject of an extensive captive breeding and reintroduction program. Wyoming toads in captivity rarely ovulate spontaneously and hormonal induction is used to ovulate females or to stimulate spermiation in males. With hormonal induction, ovulation is unreliable and egg numbers are low. The sequential administration of anovulatory doses of hormones (priming) has increased egg numbers and quality in both anurans and fish. Consequently, we tested the efficacy of a combination of human Chorionic Gonadotrophin (hCG) and Luteinizing Hormone Releasing Hormone analogue (LHRHa) administered as one dose, or two or three sequential doses to Bufo baxteri on egg numbers, fertilization and early embryo development. Spawning toads deposited eggs into Simplified Amphibian Ringers (SAR) solution to enable controlled in-vitro fertilization (IVF) with sperm from hormonally induced male toads. Unprimed females receiving a single mixed normally ovulatory dose of 500 IU hCG plus 4 micrograms of LHRHa produced no eggs. Whereas females primed with this dose and an anovulatory dose (100 IU hCG and 0.8 micrograms of LHRHa) of the same hormones, or primed only with an anovulatory dose, spawned after then receiving an ovulatory dose. Higher total egg numbers were produced with two primings than with one priming. Moreover, two primings produced significantly more eggs from each individual female than one priming. The cleavage rate of eggs was not found to differ between one or two primings. Nevertheless, embryo development with eggs from two primings gave a significantly greater percentage neurulation and swim-up than those from one priming. Of the male toads receiving a single dose of 300 IU hCG, 80% produced spermic urine with the greatest sperm concentration 7 hours post-administration (PA). However, peak sperm motility (95%) was achieved at 5 hours PA and remained relatively constant until declining 20 hours PA. In conclusion, Bufo baxteri

  2. Retina damage after exposure to UVA radiation on the early developmental stages of the Egyptian toad Bufo regularis Reuss

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    Alaa El-Din H. Sayed

    2016-10-01

    Full Text Available The present study was carried out to investigate the histological and histochemical changes in the retina on different developmental stages of Egyptian toad Bufo regularis. Our experiment started when tadpoles begin to feed. The adapted embryos are divided into 3 large tanks of 200 embryos each, collections of samples started from feeding age every three days. Both histological and histochemical results showed that the general architecture of the retina organ is correlated with the state of development. Therefore, it displayed different characteristic features depending on the investigated developmental stage starting from the larval stage (feeding began, stage 44 and ending with the post-metamorphic stage 66. Also, the present work aimed to study the chronic effects of UVA on the retina structure of B. regularis during development and metamorphosis for the first time.

  3. Oxidative stress, endocrine disruption, and malformation of Bufo gargarizans embryo exposed to sub-lethal cadmium concentrations.

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    Wu, Chao; Zhang, Yuhui; Chai, Lihong; Wang, Hongyuan

    2017-01-01

    Thyroid hormone (TH) is critical for vertebrate postembryonic development as well as embryonic development. Chinese toad (Bufo gargarizans) embryos were exposed to different concentrations of cadmium (5, 50, 100, 200 and 500μg Cd L-1) for 7days. Malformations were monitored daily, and growth and development of embryos were measured at day 4 and 7, and type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. In addition, superoxide dismutase (SOD), glutathione peroxidase (GPx) and heat shock proteins (HSPs) mRNA expression were examined to evaluate the ability of scavenging ROS. Our results demonstrated a bimodal inhibitory effect of Cd on the embryo growth and development of Bufo gargarizans. Reduced mean stage, total length and weight were observed at 5, 50, 200 and 500, but not at 100μg Cd L-1. Embryos malformation occurred in all cadmium treatments. Morphological abnormalities of embryos are characterized by axial flexures, abdominal edema, stunted growth and fin flexure. Real-time PCR results show that exposure to cadmium down-regulated TRα and Dio3 mRNA expression and up-regulated Dio2 mRNA level. SOD and GPx mRNA expression was significantly up-regulated after cadmium exposure. We concluded that cadmium could change mRNA expression of TRα, Dio2 and Dio3 leading the inhibition of growth and development of B. gargarizans embryo, which suggests that cadmium might have the endocrine-disrupting effect in embryos. Moreover, the reduced ability of scavenging ROS induced by cadmium might be responsible for the teratogenic effects of cadmium. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Dry Skin (Xerosis)

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    ... Dry skin: Symptoms Dry skin: Causes Dry skin: Treatment Dry skin: Tips Tips Dry skin: Tips for managing Here are tips that can prevent dry skin or keep it from getting worse. Do not use hot water . Hot water removes your natural skin oils more ...

  5. Skin - clammy

    Science.gov (United States)

    ... the clammy skin may be due to heat exhaustion and the person is awake and can swallow: Have the person drink plenty of (non-alcoholic) fluids Move the person to a cool, shaded place When to Contact a Medical Professional Seek immediate medical help if the person has ...

  6. Skin Cancer Foundation

    Science.gov (United States)

    ... Host a Fundraising Event | About Us | Store The Skin Cancer Foundation The Skin Cancer Foundation is the only ... Handbook A "Sunscreen Gene"? Skin Cancer Facts & Statistics Skin Cancer Treatment Glossary Information on medications and procedures The ...

  7. Skin Cancer Treatment

    Science.gov (United States)

    ... Skin Cancer Skin Cancer Screening Research Skin Cancer Treatment (PDQ®)–Patient Version General Information About Skin Cancer ... Certain factors affect prognosis (chance of recovery) and treatment options. The prognosis (chance of recovery ) depends mostly ...

  8. Skin lesion removal

    Science.gov (United States)

    Shave excision - skin; Excision of skin lesions - benign; Skin lesion removal - benign; Cryosurgery - skin, benign; BCC - removal; Basal cell cancer - removal; Actinic keratosis - removal; Wart - removal; Squamous cell - removal; ...

  9. Skin lymphoma.

    Science.gov (United States)

    Morris, S L

    2012-06-01

    Lymphoma arising from the skin is the second most common site of extra-nodal non-Hodgkin's lymphoma. Over the last 25 years, the incidence has been rising. There is now a new World Health Organization/European Organization for Research and Treatment of Cancer joint classification for cutaneous lymphomas and new proposed International Society for Cutaneous Lymphomas/European Organization for Research and Treatment of Cancer staging systems. This overview examines the role of radiotherapy in the current management of cutaneous T- and B-cell lymphomas encompassing technological advances, new systemic therapies and novel radio-enhancing therapies now available. Modern total skin electron beam radiotherapy and the current low-dose and combination approaches are reviewed. Radiotherapy has remained the most successful treatment for cutaneous lymphoma over the last 50 years and with the technological advances and combination approaches available now and in the future will remain so for the next 50 years. Copyright © 2012. Published by Elsevier Ltd.

  10. Skin Keratins.

    Science.gov (United States)

    Wang, Fengrong; Zieman, Abigail; Coulombe, Pierre A

    2016-01-01

    Keratins comprise the type I and type II intermediate filament-forming proteins and occur primarily in epithelial cells. They are encoded by 54 evolutionarily conserved genes (28 type I, 26 type II) and regulated in a pairwise and tissue type-, differentiation-, and context-dependent manner. Keratins serve multiple homeostatic and stress-enhanced mechanical and nonmechanical functions in epithelia, including the maintenance of cellular integrity, regulation of cell growth and migration, and protection from apoptosis. These functions are tightly regulated by posttranslational modifications as well as keratin-associated proteins. Genetically determined alterations in keratin-coding sequences underlie highly penetrant and rare disorders whose pathophysiology reflects cell fragility and/or altered tissue homeostasis. Moreover, keratin mutation or misregulation represents risk factors or genetic modifiers for several acute and chronic diseases. This chapter focuses on keratins that are expressed in skin epithelia, and details a number of basic protocols and assays that have proven useful for analyses being carried out in skin. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Comparative transcriptome analyses reveal the genetic basis underlying the immune function of three amphibians' skin.

    Science.gov (United States)

    Fan, Wenqiao; Jiang, Yusong; Zhang, Meixia; Yang, Donglin; Chen, Zhongzhu; Sun, Hanchang; Lan, Xuelian; Yan, Fan; Xu, Jingming; Yuan, Wanan

    2017-01-01

    Skin as the first barrier against external invasions plays an essential role for the survival of amphibians on land. Understanding the genetic basis of skin function is significant in revealing the mechanisms underlying immunity of amphibians. In this study, we de novo sequenced and comparatively analyzed skin transcriptomes from three different amphibian species, Andrias davidianus, Bufo gargarizans, and Rana nigromaculata Hallowell. Functional classification of unigenes in each amphibian showed high accordance, with the most represented GO terms and KEGG pathways related to basic biological processes, such as binding and metabolism and immune system. As for the unigenes, GO and KEGG distributions of conserved orthologs in each species were similar, with the predominantly enriched pathways including RNA polymerase, nucleotide metabolism, and defense. The positively selected orthologs in each amphibian were also similar, which were primarily involved in stimulus response, cell metabolic, membrane, and catalytic activity. Furthermore, a total of 50 antimicrobial peptides from 26 different categories were identified in the three amphibians, and one of these showed high efficiency in inhibiting the growth of different bacteria. Our understanding of innate immune function of amphibian skin has increased basis on the immune-related unigenes, pathways, and antimicrobial peptides in amphibians.

  12. Comparative transcriptome analyses reveal the genetic basis underlying the immune function of three amphibians’ skin

    Science.gov (United States)

    Zhang, Meixia; Yang, Donglin; Chen, Zhongzhu; Lan, Xuelian; Yan, Fan; Xu, Jingming; Yuan, Wanan

    2017-01-01

    Skin as the first barrier against external invasions plays an essential role for the survival of amphibians on land. Understanding the genetic basis of skin function is significant in revealing the mechanisms underlying immunity of amphibians. In this study, we de novo sequenced and comparatively analyzed skin transcriptomes from three different amphibian species, Andrias davidianus, Bufo gargarizans, and Rana nigromaculata Hallowell. Functional classification of unigenes in each amphibian showed high accordance, with the most represented GO terms and KEGG pathways related to basic biological processes, such as binding and metabolism and immune system. As for the unigenes, GO and KEGG distributions of conserved orthologs in each species were similar, with the predominantly enriched pathways including RNA polymerase, nucleotide metabolism, and defense. The positively selected orthologs in each amphibian were also similar, which were primarily involved in stimulus response, cell metabolic, membrane, and catalytic activity. Furthermore, a total of 50 antimicrobial peptides from 26 different categories were identified in the three amphibians, and one of these showed high efficiency in inhibiting the growth of different bacteria. Our understanding of innate immune function of amphibian skin has increased basis on the immune-related unigenes, pathways, and antimicrobial peptides in amphibians. PMID:29267366

  13. Ocorrência de Amblyomma fuscum Neumann, 1899 e Amblyomma humerale Koch, 1844 (Acari: Ixodidae em Bufo arenalis no estado de São Paulo, Brasil Occurence of Amblyomma fuscum Neumann, 1899 and Amblyomma humerale Koch, 1844 (Acari: Ixodidae in Bufo arenalis in the state of São Paulo, Brazil

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    Afonso Lodovico Sinkoc

    1997-06-01

    Full Text Available O objetivo deste trabalho é relatar a ocorrência do parasitismo monoespecífico de A. fuscum NEUMANN, 1899 e A. humerale KOCH, 1844 em sapos (Bufo arenalis no Município de Rosana, Estado de São Paulo, Brasil. Este relato caracteriza um novo hospedeiro e uma nova localização geográfica para estas duas espécies de carrapatos.The objective of this work is to describe the occurence of the monoespecific parasitism of A. fuscum NEUMANN, 1899 and A. humerale KOCH, 1844 in toads (Bufo arenalis from the County of Rosana, State of São Paulo, Brazil. This is the description of a new host and new geographic site for those two species.

  14. One year in the life of Bufo punctatus: annual patterns of body temperature in a free-ranging desert anuran

    Science.gov (United States)

    Rausch, Candice M.; Starkweather, Peter L.; van Breukelen, Frank

    2008-06-01

    The Mojave Desert is characterized by hot dry summers and cold winters. The red-spotted toad ( Bufo ( Anaxyrus) punctatus) is the predominant anuran species; yet little is known of their thermal histories and strategies to avoid temperature extremes. We measured body temperature ( T b) in free-ranging adult toads across all four seasons of a year using implanted data loggers. There is marked individual variation in the temperatures experienced by these toads. As expected, toads generally escape extreme seasonal and diel temperature fluctuations. However, our data demonstrate a much wider estimated T b range than was previously assumed. Though often for short periods, red-spotted toads do experience T b as low as 3.1°C and as high as 39.1°C. All animals showed periods of prolonged thermal stability in cooler months and wider diel oscillations in warmer months. Red-spotted toad thermal history is likely a function of site choice; the exploitation of different refuges results in diverse thermal experiences. These data represent the most complete record of thermal experiences for a desert anuran and reveal greater extremes in body temperature than previously suggested.

  15. Wildfire effects on water temperature and selection of breeding sites by the Boreal Toad (Bufo boreas) in seasonal wetlands

    Science.gov (United States)

    Hossack, B.R.; Corn, P.S.

    2008-01-01

    Disturbances can significantly affect the thermal regime and community structure of wetlands. We investigated the effect of a wildfire on water temperature of seasonal, montane wetlands after documenting the colonization of recently burned wetlands by the Boreal Toad (Bufo boreas boreas). We compared the daily mean temperature, daily maximum temperature, and accumulated growing degree days measured on the north shore of three classes of wetlands: unburned wetlands, burned wetlands that were colonized by breeding toads, and burned wetlands that were not colonized. We hypothesized that toads colonized burned wetlands because they were warmer than unburned wetlands and selected specific burned wetlands because they were warmer than neighboring burned sites. There was weak evidence that toads selected burned wetlands with higher temperature maxima; however, the differences were small (???1??C) and were not supported when accounting for geography and wetland features. We also found no evidence that burning the forest around wetlands increased water temperatures two and three years after the fire. Unburned wetlands had higher daily mean and maximum temperatures and accrued more growing degree days than either class of burned wetlands. Temperature differences among groups of wetlands seemed to be driven by subtle differences in geography. We suspect we did not find warmer temperatures in burned wetlands because all of the wetlands we monitored already had open canopies and the fire likely resulted in only small increases in incident radiation. Copyright ?? 2008. Blake R. Hossack. All rights reserved.

  16. Expression pattern of glycoconjugates in the integument of Bufo ictericus (Anuran, Bufonidae): biochemical and histochemical (lectin) profiles.

    Science.gov (United States)

    de Brito Gitirana, Lycia; Azevedo, Rodrigo Alves; Pelli, Adriana Alves

    2007-12-01

    Mucous consists of glycoproteins and proteoglycans produced by specific secretory cells (mucocytes). In anurans the cutaneous mucous is produced by intradermal glands and displays both mechanical and chemical protection functions. Indeed, mucous maintains the integument moist and facilitates gas exchange (cutaneous respiration). In this work, the carbohydrate moiety distribution was investigated in the integument of Bufo ictericus using conventional and lectin histochemistry to describe the pattern of cutaneous glycoconjugate expression, including both secretory and structural proteoglycans. As a preliminary step, the descendent chromatography in Whatmann 1MM paper was undertaken to prepare the histochemical trials involving the lectins. In B. ictericus, the integument exhibits the basic morphological structure found in lower terrestrial vertebrates: the epidermis is a keratinized squamous stratified epithelium supported by spongious and compact layers. The spongy dermis contain secretory portion of both mucous and serous (or poison) glands. The paper chromatography identified galactose, fucose and mannose as characteristic sugar residues. The secretory cells of the mucous gland in the dermis, as well as the interstice between the stratum corneum and the subjacent stratum spinosum in the epidermis exhibit alpha-l-fucose and alpha-galactose residues. The serous glands give no reaction. The alpha-mannose residue was detected in the extracellular matrix of spongious dermis, but not in the dermal glands. The different glycoconjugate location reflects in two glycoconjugates categories: the secretory which participate in the water flow regulation, and the structural which is involved in the dermal maintenance.

  17. Chronic exposure to coal fly ash causes minimal changes in corticosterone and testosterone concentrations in male southern toads Bufo terrestris.

    Science.gov (United States)

    Ward, C K; Mendonça, M T

    2006-08-01

    More than 50% of the electricity in the United States is produced by coal-burning power plants. The byproduct of coal-burning plants is coal fly ash, which contains increased concentrations of trace metals and is disposed of in collection basins. Southern toads (Bufo terrestris) frequently use these basins for reproduction. Male toads were collected in spring 2001 and 2002 from an ash basin and a reference site and divided into four groups: toads collected at the control site and maintained on (1) control substrate and food or (2) ash and contaminated food and toads collected at the ash site and maintained in (3) control or (4) ash conditions. Blood was collected periodically during 5 months to determine testosterone and corticosterone concentrations. Reference to ash toads exhibited a significant, transient increase in corticosterone at 4 weeks, but neither corticosterone nor testosterone continued to increase beyond this time. In contrast, toads caught and maintained on ash did not exhibit increased corticosterone. Testosterone in these toads appeared to be unrelated to ash exposure. This unexpected lack of a corticosterone response and no effect on testosterone suggests that toads chronically exposed to trace metals can acclimate to a polluted environment, but they may still experience subtle long-term consequences.

  18. Sexual differences in the post-breeding movements and habitats selected by Western toads (Bufo boreas) in southeastern Idaho

    Science.gov (United States)

    Bartelt, Paul E.; Peterson, Charles R.; Klaver, Robert W.

    2004-01-01

    We used radio-telemetry to study the movements and habitat use of Western toads (Bufo boreas) in the Targhee National Forest in southeastern Idaho. Eighteen toads (10 male and 8 female) that bred in a seasonally flooded pond, were fitted with radio-transmitters, tracked, and their movements mapped and analyzed with global positioning and geographic information systems. We also analyzed their patterns of habitat selection at micro- and macro-scales by comparing sites used by toads with randomly selected sites. After breeding, two male and six female toads left the breeding pond and used terrestrial habitats extensively. Male and female toads showed different patterns of movement and habitat use, although all toads seemed to behave in ways that reduced loss of body water (e.g., such as traveling on nights of high humidity). Male toads traveled shorter distances from the pond than females (581 ± 98 m and 1105 ± 272 m, respectively). Female toads used terrestrial habitats extensively and were selective of cover types (e.g., shrub) that provided greater protection from dehydration. Female toads also preferred certain habitat edges and open forests over forests with closed canopies or clearcuts. Information from this study can assist land managers in establishing protective buffers and managing forests for the protection of toad populations.

  19. Characterization and quantification of corticosteroid-binding globulin in a southern toad, Bufo terrestris, exposed to coal-combustion-waste

    Energy Technology Data Exchange (ETDEWEB)

    Ward, C.K.; Fontes, C.; Breuner, C.W.; Mendonca, M.T. [Auburn University, Auburn, AL (USA). Dept. of Biological Science

    2007-05-15

    Corticosteroid-binding globulin (CBG) is a plasma protein that binds corticosterone and may regulate access of hormone to tissues. The role of CBG during a stress response is not clear. In this study, southern toads, Bufo terrestris, were exposed to a chronic pollutant (coal-combustion-waste), to determine changes in CBG and free corticosterone levels. Since toads exposed to chronic pollutants in previous studies did not exhibit the predicted changes in metabolic rate and mass, but did experience a significant elevation in total corticosterone, we hypothesized that CBG would likewise increase and thus, mitigate the effects of a chronic (i.e. 2 months) pollutant stressor. To conduct this study, we first characterized the properties of CBG in southern toads. After characterization, we monitored the changes in CBG, total corticosterone, and free corticosterone in male toads that were exposed to either coal-combustion-waste or control conditions. CBG increased in all groups throughout the experiment. Total corticosterone, on the other hand, was only significantly elevated at four weeks of exposure to coal-combustion-waste. The increase in CBG did not parallel the increase in total corticosterone; as a result, free corticosterone levels were not buffered by CBG, but showed a peak at four weeks similar to total corticosterone. This finding indicates that, in this species, CBG may not provide a protective mechanism during long-term pollution exposure.

  20. Mortality and toxin bioaccumulation in Bufo marinus following exposure to Cylindrospermopsis raciborskii cell extracts and live cultures

    Energy Technology Data Exchange (ETDEWEB)

    White, S.H. [Freshwater Ecology Group, Centre for Environmental Management, Central Queensland University, Building 6, Bruce Highway, Rockhampton, QLD 4702 (Australia)]. E-mail: s.white@cqu.edu.au; Duivenvoorden, L.J. [Freshwater Ecology Group, Centre for Environmental Management, Central Queensland University, Building 6, Bruce Highway, Rockhampton, QLD 4702 (Australia)]. E-mail: l.duivenvoorden@cqu.edu.au; Fabbro, L.D. [Freshwater Ecology Group, Centre for Environmental Management, Central Queensland University, Building 6, Bruce Highway, Rockhampton, QLD 4702 (Australia)]. E-mail: l.fabbro@cqu.edu.au; Eaglesham, G.K. [Queensland Health Scientific Services, Kessels Road, Coopers Plains, QLD 4109 (Australia)]. E-mail: geoff_eaglesham@health.qld.gov.au

    2007-05-15

    Cylindrospermopsis raciborskii is a cyanobacterium responsible for the production of the toxin, cylindrospermopsin (CYN). Tadpoles of the cane toad Bufo marinus were exposed to freeze-thawed whole cell extracts or live cultures of C. raciborskii containing maximum CYN concentrations of 400 {mu}g L{sup -1} or 232 {mu}g L{sup -1}, respectively. Exposure to live culture treatment solutions resulted in up to 66% mortality of B. marinus, whereas tadpoles exposed to whole cell extracts containing similar toxin concentrations survived. Decreases in relative growth rates and time spent for swimming were recorded from tadpoles during both types of exposure regimes. Bioconcentration of CYN was not evident following exposure to whole cell extracts containing extracellular toxin. In contrast exposure to live cultures, which contained cell-bound toxin, resulted in maximum average tissue concentrations of 895 {mu}g free-CYN kg{sup -1} fresh weight. This is the first investigation of C. raciborskii exposure effects and toxin bioaccumulation in the developmental stages of an amphibian. - Cane toad tadpoles experienced adverse effects and bioaccumulation of toxin following exposure to the cyanobacterium Cylindrospermopsis raciborskii.

  1. Chronic exposure to coal fly ash causes minimal changes in corticosterone and testosterone concentrations in male southern toads Bufo terrestris

    Energy Technology Data Exchange (ETDEWEB)

    Ward, C.K.; Mendonca, M.T. [Auburn University, Montgomery, AL (United States). Dept. of Biology

    2006-08-15

    More than 50% of the electricity in the United States is produced by coal-burning power plants. The byproduct of coal-burning plants is coal fly ash, which contains increased concentrations of trace metals and is disposed of in collection basins. Southern toads (Bufo terrestris) frequently use these basins for reproduction. Male toads were collected in spring 2001 and 2002 from an ash basin and a reference site and divided into four groups: toads collected at the control site and maintained on (1) control substrate and food or (2) ash and contaminated food and toads collected at the ash site and maintained in (3) control or (4) ash conditions. Blood was collected periodically during 5 months to determine testosterone and corticosterone concentrations. Reference to ash toads exhibited a significant, transient increase in corticosterone at 4 weeks, but neither corticosterone nor testosterone continued to increase beyond this time. In contrast, toads caught and maintained on ash did not exhibit increased corticosterone. Testosterone in these toads appeared to be unrelated to ash exposure. This unexpected lack of a corticosterone response and no effect on testosterone suggests that toads chronically exposed to trace metals can acclimate to a polluted environment, but they may still experience subtle long-term consequences.

  2. Diet of southern toads (Bufo terrestris) in loblolly pine (Pinus taeda) stands subject to coarse woody debris manipulations.

    Energy Technology Data Exchange (ETDEWEB)

    Moseley, Kurtis R.; Steven B. Castleberry; James L. Hanula; Mark Ford.

    2005-04-01

    ABSTRACT In the southeastern United States, coarse woody debris (CWD) typically harbors high densities of invertebrates. However, its importance as a foraging substrate for southeastern amphibians is relatively unknown. We examined effects of CWD manipulations on diet composition of southern toads (Bufo terrestris) in upland loblolly pine (Pinus taeda) stands in the Coastal Plain of South Carolina. Twelve 9.3-ha plots were assigned one of the following treatments: removal- all CWD _10 cm in diameter and _60 cm long removed; downed- five-fold increase in volume of down CWD; and unmanipulated control stands. We collected southern toads _4 cm snout-vent length (SVL) during 14 d sampling periods in June and October 2002, June 2003 and during a 28 d sampling period in April 2003. We collected 80, 36 and 35 southern toads in control, downed and removal treatments, respectively. We found no difference in relative abundance or frequency of invertebrate groups consumed among treatments (P.0.05). Average body weight (g), SVL (cm) and stomach content weight (g wet) of individuals also were similar among treatments (P . 0.05). The role of CWD as a foraging substrate for southern toads in loblolly pine stands of the southeastern Coastal Plain may be negligible, at least in the early stages of decay.

  3. Long-term effect of heavy-metal pollution on diversity of gastrointestinal microbial community of Bufo raddei.

    Science.gov (United States)

    Zhang, Wenya; Guo, Rui; Yang, Ying; Ding, Jian; Zhang, Yingmei

    2016-09-06

    Gastrointestinal (GI) microbiota plays a very important role in maintaining its host's health. However, the effects of environmental contamination on the GI microbiota homeostasis of amphibians have not yet been reported. The present study reveals the long-term effect of natural heavy-metal pollution on the GI microbial community diversity and structural changes of Bufo raddei (B. raddei). Basing on the 16S rRNA sequencing method, the GI microbiota of B. raddei from a heavily heavy-metal-polluted area (Baiyin, (BY)) and a relatively unpolluted area (Liujiaxia, (LJX)) were profiled. The results showed that heavy-metal pollution had caused significant shifts in the composition of the GI microbiota both at the phylum and genus levels. Specifically, Bacteroidetes dominated in the GI tract of B. raddei from BY, while Tenericutes was much more common in those from LJX. The ratio of Firmicutes/Bacteroidetes and the proportion of probiotics in the GI microbiota of B. raddei from BY were reduced compared to those from LJX, as well. Heavy-metal pollution also induced in a reduction of species diversity and decreased proportion of unique operational taxonomic units in the GI tract. In short, our results demonstrate that long-term heavy-metal exposure re-shaped the composition and decreased the species diversity of GI microbiota of B. raddei; our results also represent a novel approach to uncover the toxic effects of pollution on amphibians. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Anyone Can Get Skin Cancer

    Science.gov (United States)

    ... of Skin Cancer Skin Cancer Screening Research Anyone Can Get Skin Cancer Order the free Anyone Can ... rarely, younger children can develop skin cancer. How can people with dark skin get skin cancer? Although ...

  5. Risks of Skin Cancer Screening

    Science.gov (United States)

    ... of Skin Cancer Skin Cancer Screening Research Skin Cancer Screening (PDQ®)–Patient Version What is screening? Go to ... all skin colors can get skin cancer. Skin Cancer Screening Key Points Tests are used to screen for ...

  6. Skin Allergy Quiz

    Science.gov (United States)

    ... time. Some common medications that can cause skin allergy include penicillin, sulfa drugs, barbiturates and anticonvulsants just to mention a few. Some of the symptoms from drug allergies might be hives, skin rash, itchy skin or ...

  7. Allergy testing - skin

    Science.gov (United States)

    ... allergy skin tests if you have: Hay fever ( allergic rhinitis ) and asthma symptoms that are not well controlled with medicine Hives and angioedema Food allergies Skin rashes ( dermatitis ), in which the skin ...

  8. Morphological and genetic differentiation among Chilean populations of Bufo spinulosus (Anura: Bufonidae Diferenciación morfológica y genética entre poblaciones chilenas de Bufo spinulosus (Anura: Bufonidae

    Directory of Open Access Journals (Sweden)

    Marco A. Méndez

    2004-09-01

    Full Text Available Bufo spinulosus has a wide and fragmented range distribution in Chile (18° to 33° S along altitudinal and latitudinal gradients. Genetic variation was estimated using RAPD (Random Amplified Polymorphic DNA markers in 10 populations from northern and central Chile. Morphometric and genetic information was analyzed as a function of geographical origin. The correlation between genetic and morphometric differentiation was analyzed by the Mantel test. An increase in body size as a function of latitude was observed. Specimens from El Tatio had the smallest body size and the greatest morphometric divergence. The AMOVA applied to genetic data indicated that 57.85 % of the variance is explained by interregional differences and that 30.12 % of the variance is found within populations. Low levels of within-regions genetic differentiation was observed in northern populations while higher levels of genetic differentiation was found in populations from central Chile. Mantel tests revealed a significant, positive correlation between genetic variation and geographic distance. When we excluded El Tatio population, Mantel test analyses showed significant correlations between morphological distance and genetic and geographic distances. We discuss whether water temperature could explain the morphological divergence observed in individuals from El TatioBufo spinulosus presenta una amplia y fragmentada distribución en Chile (18º a 33º S a lo largo de gradientes altitudinales y latitudinales. La variación genética fue estimada utilizando marcadores RAPD ("Random Amplified Polymorphic DNA" en diez poblaciones del norte y centro de Chile. La información morfométrica y genética fue analizada en función de la procedencia geográfica. La correlación entre diferenciación genética y morfométrica fue analizada utilizando la prueba de Mantel. Se observó un incremento en el tamaño corporal en función de la latitud. Los individuos de El Tatio mostraron el tama

  9. Expression pattern of glycoconjugates in the Bidderian and ovarian follicles of the Brazilian toad Bufo ictericus analyzed by lectin histochemistry

    Directory of Open Access Journals (Sweden)

    C. F. Farias

    Full Text Available The Bidder's organ and ovary of the Brazilian toad Bufo ictericus were studied by light microscopy, using hematoxylin-eosin (HE and periodic acid Schiff (PAS staining. The expression and distribution of carbohydrate moieties was analyzed by lectin histochemistry, using 8 lectins with different carbohydrate specificities: Ulex europaeus (UEA I, Lens culinaris (LCA, Erythrina cristagalli (ECA, Arachis hypogaea (PNA, Ricinus communis (RCA I, Aleuria aurantia (AAA, Triticum vulgaris (WGA, and Glycine maximum (SBA. The results showed that the Bidderian zona pellucida presented alpha-mannose, alpha-L-fucose, beta-D-galactose, N-acetyl-D-glucosamine, and alpha/beta-N-acetyl-galactosamine residues. The Bidderian follicular cells showed the presence of beta-D-galactose and N-acetyl-D-glucosamine. In the extracellular matrix, alpha-mannose and alpha/beta-N-acetyl-galactosamine residues were detected. The ovarian zona pellucida showed alpha-L-fucose, N-acetyl-D-glucosamine, alpha/beta-N-acetyl-galactosamine residues, and alpha-mannose and N-acetyl-D-glucosamine residues were detected in the follicular cells. Thus, the zona pellucida in both organs contains N-acetyl-D-glucosamine, and alpha/beta-N-acetyl-galactosamine residues. alpha-L-fucose residues were detected in the zona pellucida of both organs, using different lectins. Considering that beta-D-galactose residue was absent from ovary but present in the Bidder's organ, this sugar residue may play an important role in follicle development, blocking the Bidderian follicles and preventing further development of the Bidder's organ into a functional ovary.

  10. Mitochondrial Ca2+ homeostasis during Ca2+ influx and Ca2+ release in gastric myocytes from Bufo marinus

    Science.gov (United States)

    Drummond, Robert M; Mix, T Christian H; Tuft, Richard A; Walsh, John V; Fay, Fredric S

    2000-01-01

    The Ca2+-sensitive fluorescent indicator rhod-2 was used to monitor mitochondrial Ca2+ concentration ([Ca2+]m) in gastric smooth muscle cells from Bufo marinus. In some studies, fura-2 was used in combination with rhod-2, allowing simultaneous measurement of cytoplasmic Ca2+ concentration ([Ca2+]i) and [Ca2+]m, respectively. During a short train of depolarizations, which causes Ca2+ influx from the extracellular medium, there was an increase in both [Ca2+]i and [Ca2+]m. The half-time (t½) to peak for the increase in [Ca2+]m was considerably longer than the t½ to peak for the increase in [Ca2+]i. [Ca2+]m remained elevated for tens of seconds after [Ca2+]i had returned to its resting value. Stimulation with caffeine, which causes release of Ca2+ from the sarcoplasmic reticulum (SR), also produced increases in both [Ca2+]i and [Ca2+]m. The values of t½ to peak for the increase in [Ca2+] in both cytoplasm and mitochondria were similar; however, [Ca2+]i returned to baseline values much faster than [Ca2+]m. Using a wide-field digital imaging microscope, changes in [Ca2+]m were monitored within individual mitochondria in situ, during stimulation of Ca2+ influx or Ca2+ release from the SR. Mitochondrial Ca2+ uptake during depolarizing stimulation caused depolarization of the mitochondrial membrane potential. The mitochondrial membrane potential recovered considerably faster than the recovery of [Ca2+]m. This study shows that Ca2+ influx from the extracellular medium and Ca2+ release from the SR are capable of increasing [Ca2+]m in smooth muscle cells. The efflux of Ca2+ from the mitochondria is a slow process and appears to be dependent upon the amount of Ca2+ in the SR. PMID:10713963

  11. A New Phylogeographic Pattern of Endemic Bufo bankorensis in Taiwan Island Is Attributed to the Genetic Variation of Populations

    Science.gov (United States)

    Yu, Teng-Lang; Lin, Hung-Du; Weng, Ching-Feng

    2014-01-01

    Aim To comprehend the phylogeographic patterns of genetic variation in anurans at Taiwan Island, this study attempted to examine (1) the existence of various geological barriers (Central Mountain Ranges, CMRs); and (2) the genetic variation of Bufo bankorensis using mtDNA sequences among populations located in different regions of Taiwan, characterized by different climates and existing under extreme conditions when compared available sequences of related species B. gargarizans of mainland China. Methodology/Principal Findings Phylogenetic analyses of the dataset with mitochondrial DNA (mtDNA) D-loop gene (348 bp) recovered a close relationship between B. bankorensis and B. gargarizans, identified three distinct lineages. Furthermore, the network of mtDNA D-loop gene (564 bp) amplified (279 individuals, 27 localities) from Taiwan Island indicated three divergent clades within B. bankorensis (Clade W, E and S), corresponding to the geography, thereby verifying the importance of the CMRs and Kaoping River drainage as major biogeographic barriers. Mismatch distribution analysis, neutrality tests and Bayesian skyline plots revealed that a significant population expansion occurred for the total population and Clade W, with horizons dated to approximately 0.08 and 0.07 Mya, respectively. These results suggest that the population expansion of Taiwan Island species B. bankorensis might have resulted from the release of available habitat in post-glacial periods, the genetic variation on mtDNA showing habitat selection, subsequent population dispersal, and co-distribution among clades. Conclusions The multiple origins (different clades) of B. bankorensis mtDNA sequences were first evident in this study. The divergent genetic clades found within B. bankorensis could be independent colonization by previously diverged lineages; inferring B. bankorensis originated from B. gargarizans of mainland China, then dispersal followed by isolation within Taiwan Island. Highly divergent

  12. Gene expression variations in high-altitude adaptation: a case study of the Asiatic toad (Bufo gargarizans).

    Science.gov (United States)

    Yang, Weizhao; Qi, Yin; Lu, Bin; Qiao, Liang; Wu, Yayong; Fu, Jinzhong

    2017-07-03

    Genome-wide investigation of molecular mechanisms for high-altitude adaptation has attracted great attention in the last few years. In order to understand the contribution of gene expression level variations to high-altitude adaptation in Asiatic toads (Bufo gargarizans), we implemented a reciprocal transplant experiment between low- and high-altitude sites and sequenced 12 transcriptomes from brain, heart, and liver tissues. A large number of genes with expression differences (DEGs) between high- and low-altitude individuals (193 fixed and 844 plastic) were identified, and the majority of them were tissue specific. Heart displayed the largest number of DEGs, both plastic and fixed. Fixed DEGs were particularly concentrated in functions associated with muscle contraction, and the majority of them were down-regulated in high-altitude individuals. Plastic DEGs were highly concentrated in several energy metabolism related functional categories, and the majority of them were also down-regulated at high-altitude environments. In liver samples, genes associated with nutrient metabolism experienced a broad-scale expression down-regulation in high-altitude toads. These broadly suppressed expression patterns at high altitudes are in strong contrast to those of endothermic homeotherms, suggesting poikilothermic vertebrates may have adopted different strategies at high altitudes. Our results strongly support that both genotypic specialization and phenotypic plasticity play crucial role in adaptation to high altitude for Asiatic toads. Poikilothermic vertebrates are among the most hypoxia-tolerant animals known, and many molecular mechanisms remain elusive. We hope that our results will provide useful directions for future research.

  13. Effects of Multiple Routes of Cadmium Exposure on the Hibernation Success of the American Toad (Bufo americanus)

    Science.gov (United States)

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2004-01-01

    The effects of multiple routes of cadmium exposure on juvenile American toads (Bufo americanus) were evaluated using environmentally relevant concentrations. During or after exposure, toads were individually hibernated for 172 days at approximately 4??C. The following experiments were conducted: (1) dermal exposure (hibernation in soil contaminated with up to 120 ??g Cd/ g (dry weight)); (2) injection exposure (single injection with cadmium to achieve a maximum whole-body nominal concentration of 3 ??g Cd/g (wet weight) 12 days before hibernation in uncontaminated soil); and, (3) oral exposure (feeding with mealworms containing ???16 ??g Cd/g (dry weight) for 50 days before hibernation in uncontaminated soil)., We hypothesized that sublethal levels of cadmium would become lethal during hibernation because of combined chemical and cold stress. No prehibernation mortality occurred in the injection and oral exposure studies. There was a significant treatment effect on whole-body cadmium concentration in toads orally or dermally exposed and on percent of cadmium retention in toads orally exposed. There was also a trend of increased time-to-burrowing and more toads partially buried with greater cadmium concentration in the dermal study, which indicated avoidance. In all 3 experiments, no significant differences were found among cadmium treatments in hibernation survival, percent of mass loss, or locomotor performance. However, toads fed mealworms averaging 4.7 ??g Cd/g (dry weight) had only 56% survival compared with 100% survival for controls. Although our results suggest that environmentally relevant levels of cadmium do not pose a great risk to American toads, factors such as soil type or prey species may increase cadmium bioavailability, and other amphibian species may be more sensitive to cadmium than B. americanus.

  14. Prevalence of Salmonella spp. in cane toads (Bufo marinus) from Grenada, West Indies, and their antimicrobial susceptibility.

    Science.gov (United States)

    Drake, M; Amadi, V; Zieger, U; Johnson, R; Hariharan, H

    2013-09-01

    Cloacal swabs and caecal contents sampled from 58 cane toads (Bufo marinus) in St George's parish, Grenada, during a 7-month period in 2011 were examined by an enrichment and selective culture method for presence of Salmonella spp. Twenty-four (41%) toads were positive for Salmonella spp. of which eight were Salmonella enterica serovar Javiana, and eight were S. enterica serovar Rubislaw. The other serovars were as follows: Montevideo, 6; Arechavaleta, 1; and serovar: IV:43:-:-, 1. The high frequency of isolation of serovar Javiana, an emerging human pathogen associated with several outbreaks in the recent years in the eastern United States, suggests a possible role for cane toads in transmission of this serovar. Although S. Rubislaw has been isolated from lizards, bats and cases of some human infections, there is no report of its carriage by cane toads, and in such high frequency. The rate of carriage of S. Montevideo, a cause for human foodborne outbreaks around the world was also over 10% in the 58 toads sampled in this study. The antimicrobial drug susceptibility tests against amoxicillin-clavulanic acid, ampicillin, cefotaxime, ceftazidime, ciprofloxacin, enrofloxacin, gentamicin, imipenem, nalidixic acid, streptomycin, tetracycline and trimethoprim-sulfamethoxazole showed that drug resistance is minimal and is of little concern. Antimicrobial resistance was limited to ampicillin and amoxicillin-clavulanic acid in one isolate of S. Javiana and one isolate of S. Rubislaw. This is the first report of isolation and antimicrobial susceptibilities of various Salmonella serovars not identified previously in cane toads in Grenada, West Indies. © 2012 Blackwell Verlag GmbH.

  15. Modeling amphibian energetics, habitat suitability, and movements of western toads, Anaxyrus (=Bufo) boreas, across present and future landscapes

    Science.gov (United States)

    Bartelt, Paul E.; Klaver, Robert W.; Porter, Warren P.

    2010-01-01

    Effective conservation of amphibian populations requires the prediction of how amphibians use and move through a landscape. Amphibians are closely coupled to their physical environment. Thus an approach that uses the physiological attributes of amphibians, together with knowledge of their natural history, should be helpful. We used Niche Mapper™ to model the known movements and habitat use patterns of a population of Western toads (Anaxyrus (=Bufo) boreas) occupying forested habitats in southeastern Idaho. Niche Mapper uses first principles of environmental biophysics to combine features of topography, climate, land cover, and animal features to model microclimates and animal physiology and behavior across landscapes. Niche Mapper reproduced core body temperatures (Tc) and evaporation rates of live toads with average errors of 1.6 ± 0.4 °C and 0.8 ± 0.2 g/h, respectively. For four different habitat types, it reproduced similar mid-summer daily temperature patterns as those measured in the field and calculated evaporation rates (g/h) with an average error rate of 7.2 ± 5.5%. Sensitivity analyses indicate these errors do not significantly affect estimates of food consumption or activity. Using Niche Mapper we predicted the daily habitats used by free-ranging toads; our accuracy for female toads was greater than for male toads (74.2 ± 6.8% and 53.6 ± 15.8%, respectively), reflecting the stronger patterns of habitat selection among females. Using these changing to construct a cost surface, we also reconstructed movement paths that were consistent with field observations. The effect of climate warming on toads depends on the interaction of temperature and atmospheric moisture. If climate change occurs as predicted, results from Niche Mapper suggests that climate warming will increase the physiological cost of landscapes thereby limiting the activity for toads in different habitats.

  16. Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern China

    Directory of Open Access Journals (Sweden)

    Tonglei Yu

    2012-02-01

    Full Text Available We studied the trophic ecology and microhabitat use of the Asiatic toad, Bufo gargarizans Cantor, 1842; Guentheri frog, Rana guentheri (Boulenger, 1882; and the Ricefield frog, Rana limnocharis (Boie, 1834. These three species are common around Nanchong City, in southwestern China, where they live in the same habitat before hibernation. The main objective of this study was to analyze the diets and patterns of coexistence relative to the microhabitat of each species. In the Asiatic toad, based on index of relative importance, the diet was dominated by adult Coleoptera, Isopoda, and Hymenoptera (29.53%, 22.07%, and 15.20%, respectively, while the Guenther's frog and Ricefield frog ingested predominantly Orthoptera (67.44% and 40.94%, respectively. The standardized feeding niche breadth of the Asiatic toad (0.277 was wider than that of the Guentheri frog (0.177 and Ricefield frog (0.269. The overlap in the trophic niche (prey proportion between the toad and two species of frog was low (toad vs. Guentheri frog, C H = 0.526; toad vs. Ricefield frog, C H = 0.521, while this was high for the two species of frogs (C H = 0.942. The three species also differed in microhabitat use. Asiatic toads showed strong preference for small roads close to shrubs or pre-harvest corn, while Guenther's frogs preferred bare surfaces on habitat edges, and Ricefield frogs showed a preference for bare surfaces as feeding sites in the middle of habitat. The difference in diet observed during three species seems to be explained by the difference in microhabitat use and body size of three species.

  17. Estrogens and aging skin

    OpenAIRE

    Thornton, M. Julie

    2013-01-01

    Estrogen deficiency following menopause results in atrophic skin changes and acceleration of skin aging. Estrogens significantly modulate skin physiology, targeting keratinocytes, fibroblasts, melanocytes, hair follicles and sebaceous glands, and improve angiogenesis, wound healing and immune responses. Estrogen insufficiency decreases defense against oxidative stress; skin becomes thinner with less collagen, decreased elasticity, increased wrinkling, increased dryness and reduced vascularity...

  18. Phylogeography of a widespread terrestrial vertebrate in a barely-studied Palearctic region: green toads (Bufo viridis subgroup) indicate glacial refugia in Eastern Central Asia.

    Science.gov (United States)

    Zhang, Yi-Jun; Stöck, Matthias; Zhang, Peng; Wang, Xiu-Ling; Zhou, Hui; Qu, Liang-Hu

    2008-11-01

    The phylogeography of western Palearctic species is relatively well studied, but data on Eastern Central Asia are scarce. We present one of the first data sets from a widespread terrestrial vertebrate (Bufo pewzowi) inhabiting Eastern Central Asian mountains and deserts to gain knowledge on its phylogeography in this region. We applied combined phylogenetic and demographic analyses to understand the evolutionary history using mitochondrial DNA D-loop variation of toads from 37 locations. Genetic structure of Bufo pewzowi is strongly affected by landscape: we found three haplotype groups in eastern Kazakhstan, Dzungaria and Tarim Basin, divided by the Tian Shan and Dzungarian Alatau ranges. A vicariant hypothesis may explain divergence among groups. The divergence time of the three major clades was estimated about 0.9 million years ago (confidence interval 0.5-1.4), and is discussed with respect to Quaternary uplifting and glaciation in the Tian Shan. Demographic analyses provided evidence for both historical bottlenecks and population expansions and suggested Pleistocene signatures. Glacial refugia were inferred in the Tarim Basin (around the Turpan depression), in southern Dzungaria (Urumqui region), at the northern foot of the Tian Shan (Gongnaisi) and perhaps at the Altai range (Terekti). Regional Post-Last Glacial Maximum dispersal patterns are proposed. A taxonomic hypothesis is presented. This study provides a detailed history of how a widespread terrestrial vertebrate responded to geological change and Quaternary glacial events in Eastern Central Asia and may have significance for future phylogeographic research in this understudied region.

  19. Skin Cancer Can Strike Anyone

    Science.gov (United States)

    ... this page please turn Javascript on. Feature: Skin Cancer Skin Cancer Can Strike Anyone Past Issues / Summer 2013 Table ... 76,690; deaths: 9,480. Read More "Skin Cancer" Articles Skin Cancer Can Strike Anyone / Skin Cancer: Biology, Risk ...

  20. Skin cancer in skin of color.

    Science.gov (United States)

    Bradford, Porcia T

    2009-01-01

    In general, skin cancer is uncommon in people of color when compared to Caucasians. When it does occur, it is often associated with increased morbidity and mortality. Differences in survival rates may be attributed to skin cancers being diagnosed at a more advanced stage, and socioeconomic factors such as lack of adequate insurance coverage and lack of transportation can function as barriers to timely diagnosis and early treatment. In addition to advanced stage at presentation, malignant skin lesions in skin of color often present in an atypical fashion. Because skin cancer prevention and screening practices historically have been lower among Hispanics, Blacks, and Asians, and given the changing demographics in the United States, interventions that are tailored to each of these groups will be needed. Public educational campaigns should be expanded to educate people of all skin types with emphasis on skin cancers occurring in areas not exposed to the sun (Byrd-Miles et al., 2007), since sunlight is not as important an etiologic factor in the pathogenesis of skin cancer in people of color. Dermatologists and primary care physicians should instruct their darker-skinned patients on how to perform routine skin self-examinations. Physicians should also encourage patients to ask their specialists such as their gynecologist, dentist, and ophthalmologist to look for abnormal pigmentation during routine exams. To reduce the burden of skin cancer, several prevention methods for all people have been strongly encouraged, including monthly self-examinations, daily use of SPF 30 or greater sunscreen, sunglasses with UV-absorbing lenses, and avoiding tanning booths (American Cancer Society, 2008) (see Table 7). In addition, recommendations for clinicians to promote the prevention of skin cancer in skin of color have also been made, including closely monitoring changing pigmented lesions on the palms and soles and hyperkeratotic or poorly healing ulcers in immunosuppressed patients

  1. Oily skin: an overview.

    Science.gov (United States)

    Sakuma, Thais H; Maibach, Howard I

    2012-01-01

    Oily skin (seborrhea) is a common cosmetic problem that occurs when oversized sebaceous glands produce excessive amounts of sebum giving the appearance of shiny and greasy skin. This paper overviews the main concepts of sebaceous gland anatomy and physiology, including the biosynthesis, storage and release of sebum, as well as its relationship to skin hydration and water barrier function. We also address how skin oiliness may vary according to diet, age, gender, ethnicity and hot humid climates. The deeper understanding of this skin type provides the opportunity to better guide patients regarding skin care and also assist in the development of sebosuppressive agents. Copyright © 2012 S. Karger AG, Basel.

  2. Viral Skin Diseases.

    Science.gov (United States)

    Ramdass, Priya; Mullick, Sahil; Farber, Harold F

    2015-12-01

    In the vast world of skin diseases, viral skin disorders account for a significant percentage. Most viral skin diseases present with an exanthem (skin rash) and, oftentimes, an accompanying enanthem (lesions involving the mucosal membrane). In this article, the various viral skin diseases are explored, including viral childhood exanthems (measles, rubella, erythema infectiosum, and roseola), herpes viruses (herpes simplex virus, varicella zoster virus, Kaposi sarcoma herpes virus, viral zoonotic infections [orf, monkeypox, ebola, smallpox]), and several other viral skin diseases, such as human papilloma virus, hand, foot, and mouth disease, molluscum contagiosum, and Gianotti-Crosti syndrome. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Effects of Petrol Exposure on Glucose, Liver and Muscle glycogen levels in the Common African toad Bufo regularis.

    Science.gov (United States)

    Isehunwa, G O; Yusuf, I O; Alada, A Ar

    2017-03-06

    This study investigated the effects of exposure to petrol on blood glucose, liver and muscle glycogen levels in the common African toad Bufo regularis. A total of 126 adult toads of either sex weighing between 70-100g were used for this study. The experiment was divided into three phases. The phase 1 experiment the acute toxicity test consisted of animals divided into six groups of 10 toads per group and were exposed to water (H2O), H2O + Tween 80, 2ml/l, 3ml/l, 5ml/l, and 10ml/l of petrol respectively for 96 hours using the static renewal bioassay system. In the Phase 2 experiment, the animals were exposed to H2O, H2O + Tween 80, 0.14ml/l, 0.3ml/l, 0.6ml/l, and 1.13ml/l of petrol respectively for 3 days; while in phase 3 experiment they were exposed to petrol solutions for 14 days. After the various exposures, the blood glucose, liver and muscle glycogen contents were determined using standard methods. The results of the study showed that the median lethal concentration of petrol (96 hours LC50) was 4.5ml/l and sub-lethal concentration of petrol caused mortality of animals. Exposure to petrol solutions for 3 days had no significant effect on blood glucose level of the animals but caused significant decrease in the liver and muscle glycogen levels at high concentrations. In the animals exposed to petrol solutions for 14 days, there was a significant increase in glucose levels and significant reduction in liver and muscle glycogen levels at high concentrations when compared with the control. The results show that sub-lethal concentrations of petrol can cause mortality of animals, hyperglycemia and reduction in liver and muscle glycogen levels. The effects of petrol exposure on carbohydrate metabolism depend on the concentration and duration of exposure.

  4. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  5. Neuromodulators for Aging Skin

    Science.gov (United States)

    ... Hands Age Spots Aging Skin Birthmarks Burn Scars Cellulite Crow's Feet Droopy Eyelids Excess Fat Excessive Sweating ... Hands Age Spots Aging Skin Birthmarks Burn Scars Cellulite Crow's Feet Droopy Eyelids Excess Fat Excessive Sweating ...

  6. Examine Your Skin

    Medline Plus

    Full Text Available ... Store In Memory Melanoma Info Melanoma Facts Melanoma Prevention Sunscreen Suggestions Examine Your Skin Newly Diagnosed? Understanding ... video. UPDATED: November 23, 2016 Melanoma Facts Melanoma Prevention Sunscreen Suggestions Examine Your Skin Newly Diagnosed? Understanding ...

  7. Necrotizing Skin Infections

    Science.gov (United States)

    ... Summer Camp Tips for Kids With Asthma, Allergies Antioxidants: The Good Health Helpers As Stroke 'Liquefies' Brain ... Video) Skin Cancer Additional Content Medical News Necrotizing Skin Infections By A. Damian Dhar, MD, JD, Private ...

  8. Basal cell skin cancer

    Science.gov (United States)

    Basal cell skin cancer almost never spreads. If it is left untreated, it may spread into surrounding areas and nearby tissues and bone. In these cases, treatment can injure the appearance of the skin.

  9. Skin care and incontinence

    Science.gov (United States)

    ... Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Skin care and incontinence URL of this page: //medlineplus.gov/ency/article/003976.htm Skin care and incontinence To use ...

  10. Skin lesion of blastomycosis

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/000865.htm Skin lesion of blastomycosis To use the sharing features on this page, please enable JavaScript. A skin lesion of blastomycosis is a symptom of an infection ...

  11. Skin lesion aspiration

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003451.htm Skin lesion aspiration To use the sharing features on this page, please enable JavaScript. Skin lesion aspiration is the withdrawal of fluid from a ...

  12. Examine Your Skin

    Medline Plus

    Full Text Available ... Suggestions Examine Your Skin Newly Diagnosed? Understanding Your Pathology Biopsy: The First Step Sentinel Node Biopsy Melanoma ... Suggestions Examine Your Skin Newly Diagnosed? Understanding Your Pathology Biopsy: The First Step Sentinel Node Biopsy Melanoma ...

  13. Psychoneuroimmunology and the Skin.

    Science.gov (United States)

    Honeyman, Juan F

    2016-08-23

    The nervous, immune, endocrine and integumentary systems are closely related and interact in a number of normal and pathological conditions. Nervous system mediators may bring about direct changes to the skin or may induce the release of immunological or hormonal mediators that cause pathological changes to the skin. This article reviews the psychological mechanisms involved in the development of skin diseases.

  14. Microbiome and skin diseases

    NARCIS (Netherlands)

    Zeeuwen, P.L.; Kleerebezem, M.; Timmerman, H.M.; Schalkwijk, J.

    2013-01-01

    Purpose of review: This article reviews recent findings on the skin microbiome. It provides an update on the current understanding of the role of microbiota in healthy skin and in inflammatory and allergic skin diseases. Recent findings: Advances in computing and high-throughput sequencing

  15. Microbiome and skin diseases

    NARCIS (Netherlands)

    Zeeuwen, P.L.J.M.; Kleerebezem, M.; Timmerman, H.M.; Schalkwijk, J.

    2013-01-01

    PURPOSE OF REVIEW: This article reviews recent findings on the skin microbiome. It provides an update on the current understanding of the role of microbiota in healthy skin and in inflammatory and allergic skin diseases. RECENT FINDINGS: Advances in computing and high-throughput sequencing

  16. On skin expansion.

    Science.gov (United States)

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Skin lesion removal-aftercare

    Science.gov (United States)

    Shave excision - skin aftercare; Excision of skin lesions - benign aftercare; Skin lesion removal - benign aftercare; Cryosurgery - skin aftercare; BCC - removal aftercare; Basal cell cancer - removal aftercare; Actinic keratosis - removal aftercare; Wart - ...

  18. Gram stain of skin lesion

    Science.gov (United States)

    Skin lesion gram stain ... skin sore. This procedure is called a skin lesion biopsy . Before the biopsy, your provider will numb ... means bacteria have been found in the skin lesion. Further tests are needed to confirm the results. ...

  19. Skin barrier function

    DEFF Research Database (Denmark)

    2016-01-01

    on the subject. It covers new basic research on skin markers, including results on filaggrin and on methods for the assessment of the barrier function. Biological variation and aspects of skin barrier function restoration are discussed as well. Further sections are dedicated to clinical implications of skin...... barrier integrity, factors influencing the penetration of the skin, influence of wet work, and guidance for prevention and saving the barrier. Distinguished researchers have contributed to this book, providing a comprehensive and thorough overview of the skin barrier function. Researchers in the field...

  20. Skin disease in dermatomyositis.

    Science.gov (United States)

    Zaba, Lisa C; Fiorentino, David F

    2012-11-01

    This review will provide the clinician with an update on the pathogenesis, clinical manifestations, and therapy for skin disease in dermatomyositis. Recent insights into the role for interferon in skin disease as well as the development and validation of quantitative tools to measure skin disease activity allow the possibility that, for the first time, dermatomyositis skin disease can serve as a valid outcome for clinical trials of targeted therapies. Also, the increasing appreciation of the heterogeneity of skin disease in dermatomyositis has already provided evidence that clinical subtypes of disease can provide important prognostic and diagnostic information to the clinician. It is becoming apparent that the skin inflammation alone has implications for systemic and malignancy risk in dermatomyositis patients, and that there may be several pathogenic similarities between muscle and skin inflammation in dermatomyositis. Recent data on therapy for calcinosis cutis highlights that more prospective studies are needed to evaluate how best to manage all manifestations of skin inflammation in dermatomyositis. A more careful description and classification of skin disease in dermatomyositis may allow the clinician to predict more accurately which patients will be at higher risk for cancer, lung disease, or muscle inflammation. In addition, given the similarities in perturbed gene expression between skin and muscle tissue, it is likely that analysis of a more readily evaluable target organ such as skin might shed light on mechanisms of disease propagation throughout the body.

  1. Sensitive skin: An overview

    Directory of Open Access Journals (Sweden)

    Arun C Inamadar

    2013-01-01

    Full Text Available Sensitive skin is less tolerant to frequent and prolonged use of cosmetics and toiletries. It is self-diagnosed and typically unaccompanied by any obvious physical signs of irritation. With the change in lifestyle and also with increased opportunity to use many new brands of cosmetics and toiletries, there has been an increase in females complaining of unique sensation in their facial skin. Sensitive skin presents as smarting, burning, stinging, itching, and/or tight sensation in their facial skin. The condition is found in more than 50% of women and 40% of men, creating a sizable demand for products designed to minimize skin sensitivity. Good numbers of invasive and non-invasive tests are designed to evaluate and predict the sensitive skin. Management includes guidelines for selecting suitable cosmetics and toiletries in sensitive skin individuals.

  2. Sensitive skin: an overview.

    Science.gov (United States)

    Inamadar, Arun C; Palit, Aparna

    2013-01-01

    Sensitive skin is less tolerant to frequent and prolonged use of cosmetics and toiletries. It is self-diagnosed and typically unaccompanied by any obvious physical signs of irritation. With the change in lifestyle and also with increased opportunity to use many new brands of cosmetics and toiletries, there has been an increase in females complaining of unique sensation in their facial skin. Sensitive skin presents as smarting, burning, stinging, itching, and/or tight sensation in their facial skin. The condition is found in more than 50% of women and 40% of men, creating a sizable demand for products designed to minimize skin sensitivity. Good numbers of invasive and non-invasive tests are designed to evaluate and predict the sensitive skin. Management includes guidelines for selecting suitable cosmetics and toiletries in sensitive skin individuals.

  3. Skin absorption through atopic dermatitis skin

    DEFF Research Database (Denmark)

    Halling-Overgaard, A-S; Kezic, S; Jakasa, I

    2017-01-01

    Patients with atopic dermatitis have skin barrier impairment in both lesional and non-lesional skin. They are typically exposed to emollients daily and topical anti-inflammatory medicaments intermittently, hereby increasing the risk of developing contact allergy and systemic exposed to chemicals...... ingredients found in these topical preparations. We systematically searched for studies that investigated skin absorption of various penetrants, including medicaments, in atopic dermatitis patients, but also animals with experimentally induced dermatitis. We identified 40 articles, i.e. 11 human studies...... examining model penetrants, 26 human studies examining atopic dermatitis drugs and 3 animal studies. We conclude that atopic dermatitis patients have nearly two-fold increased skin absorption when compared to healthy controls. There is a need for well-designed epidemiological and dermato...

  4. Ultrasound skin imaging.

    Science.gov (United States)

    Alfageme Roldán, F

    2014-12-01

    The interaction of high-frequency ultrasound waves with the skin provides the basis for noninvasive, fast, and accessible diagnostic imaging. This tool is increasingly used in skin cancer and inflammatory conditions as well as in cosmetic dermatology. This article reviews the basic principles of skin ultrasound and its applications in the different areas of dermatology. Copyright © 2013 Elsevier España, S.L.U. y AEDV. All rights reserved.

  5. The skin microbiome

    OpenAIRE

    Grice, Elizabeth A.; Segre, Julia A.

    2011-01-01

    The skin is the human body’s largest organ, colonized by a diverse milieu of microorganisms, most of which are harmless or even beneficial to their host. Colonization is driven by the ecology of the skin surface, which is highly variable depending on topographical location, endogenous host factors and exogenous environmental factors. The cutaneous innate and adaptive immune responses can modulate the skin microbiota, but the microbiota also functions in educating the immune system. The develo...

  6. Allergy Skin Tests

    Science.gov (United States)

    ... Histamine. In most people, this substance causes a skin response. If you don't react to histamine, your ... days or more to produce results. A positive skin test means that you may be allergic to a particular substance. Bigger wheals usually indicate a greater degree of sensitivity. A ...

  7. Deformable skinning on bones

    DEFF Research Database (Denmark)

    Larsen, Bent Dalgaard; Petersen, Kim Steen; Jakobsen, Bjarke

    2001-01-01

    Applying skin to a model is a relatively simple task to implement. Nonetheless it seems that no good resource exists that describes both the concepts and math necessary to understand and implement skinning. The intention of this article is an attempt to give a thoroughly description of the theore...

  8. Skin tribology: Science friction?

    NARCIS (Netherlands)

    van der Heide, Emile; Zeng, Xiangqiong; Masen, Marc Arthur

    2013-01-01

    The application of tribological knowledge is not just restricted to optimizing mechanical and chemical engineering problems. In fact, effective solutions to friction and wear related questions can be found in our everyday life. An important part is related to skin tribology, as the human skin is

  9. Dark Skin No Shield from Deadly Skin Cancer

    Science.gov (United States)

    ... 166194.html Dark Skin No Shield From Deadly Skin Cancer Death rates from melanoma are higher for people ... deadly melanomas, an expert warns. This type of skin cancer can be affected by genetics and is far ...

  10. Skin Diseases: Skin and Sun—Not a good mix

    Science.gov (United States)

    ... Issues Skin Diseases Skin and Sun —Not a good mix Past Issues / Fall 2008 Table of Contents ... version of this page please turn Javascript on. Good skin care begins with sun safety. Whether it ...

  11. Bionanomaterials for skin regeneration

    CERN Document Server

    Leonida, Mihaela D

    2016-01-01

    This book gives a concise overview of bionanomaterials with applications for skin regeneration. The advantages and challenges of nanoscale materials are covered in detail, giving a basic view of the skin structure and conditions that require transdermal or topical applications. Medical applications, such as wound healing, care for burns, skin disease, and cosmetic care, such as aging of the skin and photodamage, and how they benefit from bionanomaterials, are described in detail. A final chapter is devoted to the ethical and social issues related to the use of bionanomaterials for skin regeneration. This is an ideal book for researchers in materials science, medical scientists specialized in dermatology, and cosmetic chemists working in formulations. It can also serve as a reference for nanotechnologists, dermatologists, microbiologists, engineers, and polymer chemists, as well as students studying in these fields.

  12. ENVENENAMENTO DE CÃES POR BUFADIENOLÍDEOS (Substâncias encontradas na secreção das glândulas paratóides dos sapos do gênero Bufo POISONING OF DOGS BY BUFADIENOLIDES (SUBSTANCES FOUND IN THE PARATOID GLAND SECRETION OF FROGS OF THE GENUS Bufo

    Directory of Open Access Journals (Sweden)

    Lourival Pereira Nunes

    2007-09-01

    Full Text Available

    Os autores estudaram o efeito da aplicação na mucosa bucal de cães, do produto secretado pelas glândulas paratóides de sapos do gênero Bufo. Os cães apresentaram sinais de graves intoxicações, imediatamente após a aplicação do referido produto.

    In the present paper, the authors report the effects of toad’s poison in dogs. This is the first case describe in Goiás.

  13. Skin Picking Disorder

    Directory of Open Access Journals (Sweden)

    Pinar Cetinay Aydin

    2014-08-01

    Full Text Available Skin picking disorder is not a dermatological disorder and it is a table characterized with picking skin excessively and repetitively, leading to damage in skin tissue. Unlike normal picking behaviour, psychogenic skin picking is repetitive and it can lead to severe damage in the skin and even complications which constitute vital danger. While some patients define frequent but short lasting picking attacks, others define rarer attacks which last a few hours. Skin picking disorder, which is not included in the classification systems up to DSM-5 as a separate diagnosis category, is included as an independent diagnosis in Obsessive Compulsive Disorder and Associated Disorders category in DSM-5. In case reports, open label studies and double blind studies selective serotonin reuptake inhibitors are shown to be effective in the treatment of skin picking disorder. Mostly, cognitive-behaviourial techniques are used and have been proven to be useful in psychotherapy. Habit reversal is one of the behaviourial techniques which are frequently applied, give positive results in which well-being state can be maintained. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2014; 6(4.000: 401-428

  14. Skin and antioxidants.

    Science.gov (United States)

    Poljsak, Borut; Dahmane, Raja; Godic, Aleksandar

    2013-04-01

    It is estimated that total sun exposure occurs non-intentionally in three quarters of our lifetimes. Our skin is exposed to majority of UV radiation during outdoor activities, e.g. walking, practicing sports, running, hiking, etc. and not when we are intentionally exposed to the sun on the beach. We rarely use sunscreens during those activities, or at least not as much and as regular as we should and are commonly prone to acute and chronic sun damage of the skin. The only protection of our skin is endogenous (synthesis of melanin and enzymatic antioxidants) and exogenous (antioxidants, which we consume from the food, like vitamins A, C, E, etc.). UV-induced photoaging of the skin becomes clinically evident with age, when endogenous antioxidative mechanisms and repair processes are not effective any more and actinic damage to the skin prevails. At this point it would be reasonable to ingest additional antioxidants and/or to apply them on the skin in topical preparations. We review endogenous and exogenous skin protection with antioxidants.

  15. Occupational skin cancers

    Energy Technology Data Exchange (ETDEWEB)

    Gawkrodger, D.J. [Royal Hallamshire Hospital, Sheffield (United Kingdom). Dept. of Dermatology

    2004-10-01

    Skin cancer due to occupation is more common than is generally recognized, although it is difficult to obtain an accurate estimate of its prevalence. Over the past two centuries, occupational skin cancers have particularly been due to industrial exposure of men (it seems more so than women) to chemical carcinogens such as polycyclic hydrocarbons (e.g. from coal tar products) or to arsenic. Industrial processes have improved in most Western countries to limit this type of exposure, but those with outdoor occupations are still exposed to solar ultraviolet irradiation without this being widely recognized as an industrial hazard. Ionizing radiation such as X-rays can also cause skin cancer. Occupational skin cancers often resemble skin tumours found in non-occupational subjects, e.g. basal cell carcinoma, squamous cell carcinoma and malignant melanoma, but some pre-malignant lesions can be more specific and point to an occupational origin, e.g. tar keratoses or arsenical keratoses. An uncommon but well-recognized cause of occupational skin cancer is that which results from scar formation following an industrial burn. In the future it will be necessary to focus on preventative measures, e.g. for outdoor workers, the need to cover up in the sun and use sun protective creams and a campaign for earlier recognition of skin cancers, which are usually curable if treated in their early stages.

  16. The effect of soil composition and hydration on the bioavailability and toxicity of cadmium to hibernating juvenile American toads (Bufo americanus)

    Science.gov (United States)

    James, Stacy M.; Little, Edward E.; Semlitsch, Raymond D.

    2004-01-01

    The soil ecotoxicology literature has focused primarily on a few major taxa, to the neglect of other fossorial organisms such as amphibians. We selected cadmium (Cd) and the American toad (Bufo americanus) as a model contaminant and biological species to assess the impact of soil contamination on amphibian hibernation survival and post-hibernation condition. Soil sand composition (50, 70, 90%) and hydration (100, 150% water holding capacity (WHC)) were manipulated in addition to Cd concentration (0, 56, 165, 483 μg/g) to determine whether these soil properties affect toxicity. Soil Cd concentration significantly reduced survival and locomotor performance, and was correlated negatively with percent mass loss and positively with whole body Cd concentration. Higher sand content resulted in less mass loss and greater Cd uptake. Toads that were hibernated in 50% sand hydrated to 100% WHC had higher survival, less mass loss, and better sprint performance than those hibernated in 50% sand, 150% WHC. This study demonstrates that concentrations of Cd found in soil at highly contaminated sites can be bioaccumulated by hibernating amphibians and may reduce fitness. Differences in microhabitat use may cause species to vary in their exposure and susceptibility to soil contamination. The toxicity of Cd to amphibians could be greater in natural systems where there are multiple stressors and fluctuations in environmental variables.

  17. Geographic variation in life-history traits: growth season affects age structure, egg size and clutch size in Andrew's toad (Bufo andrewsi).

    Science.gov (United States)

    Liao, Wen Bo; Luo, Yi; Lou, Shang Ling; Lu, Di; Jehle, Robert

    2016-01-01

    Environmental variation associated with season length is likely to promote differentiation in life-history traits, but has been little studied in natural populations of ectotherms. We investigated patterns of variation in egg size, clutch size, age at sexual maturity, maximum age, mean age, growth rate and adult body size in relation to growth season length among 17 populations of Andrew's toad (Bufo andrewsi) at different latitudes and altitudes in the Hengduan Mountains, western China. We found that egg size, age at sexual maturity, and mean age increased with decreasing length of the growth season, whereas clutch size showed a converse cline. Body size did not increase with decreasing length of the growth season, but was tightly linked to lifetime activity (i.e. the estimated number of active days during lifetime). Males and females differed in their patterns of geographic variation in growth rates, which may be the result of forces shaping the trade-off between growth and reproduction in different environments. Our findings suggest that growth season plays an important role in shaping variation in life-history traits in B. andrewsi across geographical gradients.

  18. Drift Rather than Selection Dominates MHC Class II Allelic Diversity Patterns at the Biogeographical Range Scale in Natterjack Toads Bufo calamita

    Science.gov (United States)

    Zeisset, Inga; Beebee, Trevor J. C.

    2014-01-01

    Study of major histocompatibility complex (MHC) loci has gained great popularity in recent years, partly due to their function in protecting vertebrates from infections. This is of particular interest in amphibians on account of major threats many species face from emergent diseases such as chytridiomycosis. In this study we compare levels of diversity in an expressed MHC class II locus with neutral genetic diversity at microsatellite loci in natterjack toad (Bufo (Epidalea) calamita) populations across the whole of the species’ biogeographical range. Variation at both classes of loci was high in the glacial refugium areas (REF) and much lower in postglacial expansion areas (PGE), especially in range edge populations. Although there was clear evidence that the MHC locus was influenced by positive selection in the past, congruence with the neutral markers suggested that historical demographic events were the main force shaping MHC variation in the PGE area. Both neutral and adaptive genetic variation declined with distance from glacial refugia. Nevertheless, there were also some indications from differential isolation by distance and allele abundance patterns that weak effects of selection have been superimposed on the main drift effect in the PGE zone. PMID:24937211

  19. When new human-modified habitats favour the expansion of an amphibian pioneer species: Evolutionary history of the natterjack toad (Bufo calamita) in a coal basin.

    Science.gov (United States)

    Faucher, Leslie; Hénocq, Laura; Vanappelghem, Cédric; Rondel, Stéphanie; Quevillart, Robin; Gallina, Sophie; Godé, Cécile; Jaquiéry, Julie; Arnaud, Jean-François

    2017-09-01

    Human activities affect microevolutionary dynamics by inducing environmental changes. In particular, land cover conversion and loss of native habitats decrease genetic diversity and jeopardize the adaptive ability of populations. Nonetheless, new anthropogenic habitats can also promote the successful establishment of emblematic pioneer species. We investigated this issue by examining the population genetic features and evolutionary history of the natterjack toad (Bufo [Epidalea] calamita) in northern France, where populations can be found in native coastal habitats and coalfield habitats shaped by European industrial history, along with an additional set of European populations located outside this focal area. We predicted contrasting patterns of genetic structure, with newly settled coalfield populations departing from migration-drift equilibrium. As expected, coalfield populations showed a mosaic of genetically divergent populations with short-range patterns of gene flow, and native coastal populations indicated an equilibrium state with an isolation-by-distance pattern suggestive of postglacial range expansion. However, coalfield populations exhibited (i) high levels of genetic diversity, (ii) no evidence of local inbreeding or reduced effective population size and (iii) multiple maternal mitochondrial lineages, a genetic footprint depicting independent colonization events. Furthermore, approximate Bayesian computations suggested several evolutionary trajectories from ancient isolation in glacial refugia during the Pleistocene, with biogeographical signatures of recent expansion probably confounded by human-mediated mixing of different lineages. From an evolutionary and conservation perspective, this study highlights the ecological value of industrial areas, provided that ongoing regional gene flow is ensured within the existing lineage boundaries. © 2017 John Wiley & Sons Ltd.

  20. Structural aspects of the Eberth-Katschenko layer of Bufo ictericus integument: histochemical characterization and biochemical analysis of the cutaneous calcium (Amphibian, Bufonidae).

    Science.gov (United States)

    Azevedo, Rodrigo Alves; Pelli, Adriana Alves; Ferreira-Pereira, Antonio; de Jesus Santana, Andréa Souza; Felsemburgh, Flávia; de Brito-Gitirana, Lycia

    2005-01-01

    Anuran, such as Brazilian toad Bufo ictericus Spix, 1824, possess a calcified dermal layer called the Eberth-Katschenko (EK) layer located between the stratum spongiosum and the stratum compactum. It has been regarded as a protective barrier against desiccation or involved in storage and mobilization of calcium, or a barrier for the interchange of substances between the animal's internal and external environment. The B. ictericus integument was removed from the ventral and dorsal regions and examined by light microscopy, using histochemical techniques, and also submitted to biochemical calcium analysis. The intermediate layer is strongly basophilic and metachromatic. In the EK layer Alcian blue at different critical electrolytic concentration revealed hyaluronic acid, which coexists with the dermal calcium. We conclude that the EK layer of B. ictericus is a discontinuous layer and is formed of hyaluronic acid and a sulfated GAG different from chondroitin sulfate, heparin and heparan sulfate or keratan sulfate. The amount of cutaneous calcium is independent of region and sex. GAGs may play an important role in dermal hydric balance, protecting the animal against desiccation, and hyaluronic acid is probably able to anchor dermal calcium. Thus, all compounds of the EK layer are essential for integument integrity and functionality.

  1. Chloromyxum aegypticus n. sp. (Myxozoa: Chloromyxidae) infecting the testicular tissue of the Egyptian toad, Bufo regularis (Amphibia: Bufonidae), and its pathogenicity.

    Science.gov (United States)

    Reda, Enayat Salem Ahmed

    2010-11-01

    A new myxosporean, Chloromyxum aegypticus n. sp., is described from the testes of the Egyptian toad Bufo regularis, captured from El Mansoura locality. C. aegypticus is identified on the basis of cytology, electron microscopy and histopathology. It is distinguished from all previously reported Chloromyxum spp. by its shape, dimensions of the mature spore (9.1 ± 0.1 (9.0-9.2) μm in length  × 7.9 ± 0.1 (7.8-8.0) μm in width), polar capsules, external ridge, sporoplasm nuclei, undulating suture, locality and host. Accumulation of several hundreds of plasmodia (0.8 ± 0.3 (0.5-1.1) mm in length × 0.5 ± 0.3 (0.2-0.7) mm in width) in the testes causes their enlargement. Parasites cause destruction of the seminiferous tubule cells and complete loss of spermatozoa. Since spermatogenesis stops, this seems to be a form of "parasitic castration". This is the first known record of the genus Chloromyxum in amphibian testes.

  2. Effects of temperature on embryonic and larval development and growth in the natterjack toad (Bufo calamita in a semi-arid zone

    Directory of Open Access Journals (Sweden)

    Sanuy, D.

    2008-06-01

    Full Text Available Temperature affects the duration of embryonic and larval periods in amphibians. Plasticity in time to metamorphosis is especially important in amphibian populations of Mediterranean semi-arid zones where temperatures are high and precipitation is low, increasing the rate of pond desiccation. In order to test the influence of water temperature on the larval development and growth of the natterjack toad (Bufo calamita, we collected two spawns in a semi¿arid zone at Balaguer (Lleida, NE Iberian peninsula. Approximately 50 (+/-10 eggs (stage 14-16 were raised in the lab at different temperature conditions: 10, 15, 20, 22.5 and 25ºC with 12:12 photoperiod. The results show a lengthening of development time with decreasing temperatures and a better survival performance of B. calamita to high temperatures. However, mean size at metamorphosis was not different across treatments, thus, suggesting that this population of B. calamita requires a minimum size to complete the metamorphosis. This study is the first approach to examine the effects that climatic factors have on the growth and development of B. calamita in semi-arid zones.

  3. Quality Assessment of Serially Ultradiluted and Agitated Drug Digitalis purpurea by Emission Spectroscopy and Clinical Analysis of Its Effect on the Heart Rate of Indian Bufo melanostictus

    Directory of Open Access Journals (Sweden)

    Anup Sharma

    2013-01-01

    Full Text Available The investigation of ultradiluted (homeopathic drugs is extremely interesting and challenging, and from that point of view this study shows novelty. A study of in vivo changes in heart rate of the Indian Bufo melanostictus caused by commercially available serially ultra-diluted and agitated extract of Digitalis purpurea has been tried in order to understand their pharmacological role. RR interval (of ECG was compared after intraperitoneal administration of serially diluted and agitated Digitalis purpurea extract, diluent rectified spirit, and Digoxin in anesthetized animals. The study revealed statistically significant changes in the heart rate after application of these drugs except in case of Digoxin and the 200th serial dilution of Digitalis purpurea. The duration of RR intervals after application of the drugs was corroborative of the effect of Digoxin and Digitalis purpurea extract up to 30th dilution. Emission spectra were obtained for the experimental ultra-diluted Digitalis purpurea extract and Digoxin to identify and characterize them. The observed RR pattern and emission spectra show an association. The quality assessment of the commercial ultra-diluted organic drugs obtained from natural products may be initiated by monitoring in vivo studies on animal models.

  4. Drift rather than selection dominates MHC class II allelic diversity patterns at the biogeographical range scale in natterjack toads Bufo calamita.

    Directory of Open Access Journals (Sweden)

    Inga Zeisset

    Full Text Available Study of major histocompatibility complex (MHC loci has gained great popularity in recent years, partly due to their function in protecting vertebrates from infections. This is of particular interest in amphibians on account of major threats many species face from emergent diseases such as chytridiomycosis. In this study we compare levels of diversity in an expressed MHC class II locus with neutral genetic diversity at microsatellite loci in natterjack toad (Bufo (Epidalea calamita populations across the whole of the species' biogeographical range. Variation at both classes of loci was high in the glacial refugium areas (REF and much lower in postglacial expansion areas (PGE, especially in range edge populations. Although there was clear evidence that the MHC locus was influenced by positive selection in the past, congruence with the neutral markers suggested that historical demographic events were the main force shaping MHC variation in the PGE area. Both neutral and adaptive genetic variation declined with distance from glacial refugia. Nevertheless, there were also some indications from differential isolation by distance and allele abundance patterns that weak effects of selection have been superimposed on the main drift effect in the PGE zone.

  5. Aging changes in skin

    Science.gov (United States)

    ... It is more noticeable in sun-exposed areas (solar elastosis). Elastosis produces the leathery, weather-beaten appearance ... Good nutrition and adequate fluids are also helpful. Dehydration increases the risk of skin injury. Sometimes minor ...

  6. Designing pliable structural Skins

    DEFF Research Database (Denmark)

    Tamke, Martin; Peters, Brady; Nielsen, Stig Anton

    2013-01-01

    Structural stability can be formed through structured or seemingly unstructured approaches to fold, plead or crumble paper. This paper reports on two projects that showcase how computational design approaches can help to widen the understanding and use of structural skins....

  7. Examine Your Skin

    Medline Plus

    Full Text Available ... Doctor Glossary of Terms Resources Resources Global Resources Cancer Centers Online Resources The Melanoma Book Clinical Trials Download a Skin Self-Exam Card Download a Patient Navigation Card Events, Webinars & Videos Events, Webinars & Videos ...

  8. Examine Your Skin

    Medline Plus

    Full Text Available ... Doctor Glossary of Terms Resources Resources Global Resources Cancer Centers Online Resources The Melanoma Book Clinical Trials Download a Skin Self-Exam Card Download a Patient Navigation Card ...

  9. Allergy Skin Tests

    Science.gov (United States)

    ... medications: Know your options Allergy skin tests About Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  10. Bacterial Skin Infections

    Science.gov (United States)

    ... Summer Camp Tips for Kids With Asthma, Allergies Antioxidants: The Good Health Helpers As Stroke 'Liquefies' Brain ... Cancer Additional Content Medical News Overview of Bacterial Skin Infections By A. Damian Dhar, MD, JD, Private ...

  11. Fungal Skin Infections

    Science.gov (United States)

    ... Summer Camp Tips for Kids With Asthma, Allergies Antioxidants: The Good Health Helpers As Stroke 'Liquefies' Brain ... and itching. Some Antifungal Drugs Applied to the Skin (Topical Drugs) Amorolfine Butoconazole Butenafine Ciclopirox Clotrimazole Econazole ...

  12. Smoking and skin disease

    DEFF Research Database (Denmark)

    Thomsen, S F; Sørensen, L T

    2010-01-01

    suggest that tobacco smoking is a contributing factor in systemic lupus erythematosus, psoriasis, palmoplantar pustulosis, cutaneous squamous cell carcinoma, hidradenitis suppurativa, and genital warts. In contrast, smoking may confer some protective effects and mitigate other skin diseases, notably...

  13. Examine Your Skin

    Medline Plus

    Full Text Available ... us for One-on-One Support Donate Share Facebook Twitter Newsletter Examine Your Skin Watch the video ... develop personalized strategies with patients so they may live longer, better lives. Our Vision: A future where ...

  14. Examine Your Skin

    Medline Plus

    Full Text Available ... Download a Skin Self-Exam Card Download a Patient Navigation Card Events, Webinars & Videos Events, Webinars & Videos Melanoma Patient Video Events Host an Event Past Webinars Upcoming ...

  15. Skin, Hair, and Nails

    Science.gov (United States)

    ... they're cut off from their supply of nourishment and start to form a hard protein called ... yeast Candida . Yeast infections of the skin in older children, teens, and adults are less common. Tinea ...

  16. Skin Cancer Prevention

    Science.gov (United States)

    ... Having a weakened immune system . Being exposed to arsenic . Risk factors for melanoma skin cancer: Having a ... such as “NCI’s PDQ cancer information summary about breast cancer prevention states the risks in the following way: [ ...

  17. Skin self-exam

    Science.gov (United States)

    ... Names Skin cancer - self-exam; Melanoma - self-exam; Basal cell cancer - self-exam; Squamous cell - self-exam; ... 2015 Updated by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. ...

  18. Stages of Skin Cancer

    Science.gov (United States)

    ... with a nozzle is used to spray liquid nitrogen or liquid carbon dioxide to freeze and destroy ... or small particles to rub away skin cells. Radiation therapy Radiation therapy is a cancer treatment that ...

  19. Radiation therapy -- skin care

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000735.htm Radiation therapy - skin care To use the sharing features ... this page, please enable JavaScript. When you have radiation treatment for cancer, you may have some changes ...

  20. Spiritual and religious aspects of skin and skin disorders

    Directory of Open Access Journals (Sweden)

    Shenefelt PD

    2014-08-01

    Full Text Available Philip D Shenefelt,1 Debrah A Shenefelt2 1Dermatology and Cutaneous Surgery, University of South Florida, Tampa, 2Congregation Or Ahavah, Lutz, FL, USA Abstract: Skin and skin disorders have had spiritual aspects since ancient times. Skin, hair, and nails are visible to self and others, and touchable by self and others. The skin is a major sensory organ. Skin also expresses emotions detectable by others through pallor, coldness, "goose bumps", redness, warmth, or sweating. Spiritual and religious significances of skin are revealed through how much of the skin has been and continues to be covered with what types of coverings, scalp and beard hair cutting, shaving and styling, skin, nail, and hair coloring and decorating, tattooing, and intentional scarring of skin. Persons with visible skin disorders have often been stigmatized or even treated as outcasts. Shamans and other spiritual and religious healers have brought about healing of skin disorders through spiritual means. Spiritual and religious interactions with various skin disorders such as psoriasis, leprosy, and vitiligo are discussed. Religious aspects of skin and skin diseases are evaluated for several major religions, with a special focus on Judaism, both conventional and kabbalistic. Keywords: skin, skin disorders, spiritual, religious

  1. Skin Cancer - Multiple Languages

    Science.gov (United States)

    ... Expand Section Skin Cancer: MedlinePlus Health Topic - English Cáncer de piel: Tema de salud de MedlinePlus - español (Spanish) National Library of Medicine Ukrainian (українська ) Expand Section Skin Cancer - українська (Ukrainian) Bilingual PDF Health Information Translations Characters ...

  2. Mantoux Tuberculin Skin Test

    Centers for Disease Control (CDC) Podcasts

    2006-11-22

    Learn how to evaluate people for latent TB infection with the Mantoux tuberculin skin test. This podcast includes sections on administering and reading the Mantoux tuberculin skin test, the standard method for detecting latent TB infection since the 1930s.  Created: 11/22/2006 by National Center for HIV, STD and TB Prevention (NCHHSTP).   Date Released: 12/12/2006.

  3. ReciPlySkin

    DEFF Research Database (Denmark)

    Popovic Larsen, Olga; Andersen, Mikkel; Munk-Andersen, Niklas

    2017-01-01

    The report presents process that enbabled the production of the ReciPlySkin structure exhibited at the Circular Economy Exhibition at KADK during the Autumn 2017. The concept, design, detailed design and production are presented in this report.......The report presents process that enbabled the production of the ReciPlySkin structure exhibited at the Circular Economy Exhibition at KADK during the Autumn 2017. The concept, design, detailed design and production are presented in this report....

  4. Smoking and skin disease

    DEFF Research Database (Denmark)

    Thomsen, S F; Sørensen, L T

    2010-01-01

    Tobacco smoking is a serious and preventable health hazard that can cause or exacerbate a number of diseases and shorten life expectancy, but the role of smoking as an etiologic factor in the development of skin disease is largely unknown. Although epidemiological evidence is sparse, findings...... suggest that tobacco smoking is a contributing factor in systemic lupus erythematosus, psoriasis, palmoplantar pustulosis, cutaneous squamous cell carcinoma, hidradenitis suppurativa, and genital warts. In contrast, smoking may confer some protective effects and mitigate other skin diseases, notably...... pemphigus vulgaris, pyoderma gangrenosum, aphthous ulcers, and Behçet's disease. Various degenerative dermatologic conditions are also impacted by smoking, such as skin wrinkling and dysregulated wound healing, which can result in post-surgical complications and delayed or even arrested healing of chronic...

  5. Skin in pregnancy

    Directory of Open Access Journals (Sweden)

    Raj Sujata

    1992-01-01

    Full Text Available Screening for cutaneous disorders was undertaken in 1,175 pregnant women attending ante-natal clinic. Skin disease or STD being encountered in 114 (9.7%. Pruritus was present in 7.1 percent and was mostly due to candidiadis. The physiological skin changes were frequently observed. Candidiasis was by far the commonest infection with a 2.9 percent incidence. Syphilis was the commonest STD followed by Donovanosis and condyloma acuminata. Specific pregnancy dermatoses were seen in 1.5 percent and included prurigo gestationis, pruritic urticarial papules and plaques (PUPPP and pruritus gravidarum.

  6. Nicotinamide and the skin.

    Science.gov (United States)

    Chen, Andrew C; Damian, Diona L

    2014-08-01

    Nicotinamide, an amide form of vitamin B3, boosts cellular energy and regulates poly-ADP-ribose-polymerase 1, an enzyme with important roles in DNA repair and the expression of inflammatory cytokines. Nicotinamide shows promise for the treatment of a wide range of dermatological conditions, including autoimmune blistering disorders, acne, rosacea, ageing skin and atopic dermatitis. In particular, recent studies have also shown it to be a potential agent for reducing actinic keratoses and preventing skin cancers. © 2014 The Australasian College of Dermatologists.

  7. Responses of growth, malformation, and thyroid hormone-dependent genes expression in Bufo gargarizans embryos following chronic exposure to Pb2.

    Science.gov (United States)

    Chai, Lihong; Li, Yanbin; Chen, Zhihong; Chen, Aixia; Deng, Hongzhang

    2017-10-08

    The aim of this study was to examine the adverse effects of lead (Pb) exposure on Bufo gargarizans embryos. The 96 h-LC50 of Pb2+ for B. gargarizans embryos was determined to be 26.6 mg L-1 after an acute test. In the chronic test, B. gargarizans embryos at Gosner stage 3 were exposed to 10~2000 μg Pb2+ L-1 during embryogenesis. Total length, weight, developmental stage, and malformation were monitored. In addition, the transcript levels of type II and type III iodothyronine deiodinase (Dio2 and Dio3) and thyroid hormone receptors (TRα and TRβ) were determined to assess the thyroid-disrupting effects of Pb2+. Slightly increased growth and development of B. gargarizans embryos were observed at low concentrations of Pb2+ (10, 50, and 100 μg L-1), while retarded growth and development were found at high concentrations of Pb2+ (1000 and 2000 μg L-1). In addition, Pb2+ exposure induced morphological abnormalities, which were characterized by edema at tail, wavy fin, abdominal edema, stunted growth, hyperplasia, and axial flexures in B. gargarizans embryos. Furthermore, our results showed that exposure to 2000 μg Pb2+ L-1 decreased the transcript levels of Dio2, TRα, and TRβ, but it increased Dio3 mRNA level. In contrast, exposure to 50 μg Pb2+ L-1 increased TRα mRNA level and decreased Dio3 mRNA level. These results suggested that Pb2+ might have thyroid-disrupting effects, leading to the disruption of growth and development in B. gargarizans embryos.

  8. Fluctuating asymmetry rather than oxidative stress in Bufo raddei can be an accurate indicator of environmental pollution induced by heavy metals.

    Science.gov (United States)

    Guo, Rui; Zhang, Wenya; Ai, Shiwei; Ren, Liang; Zhang, Yingmei

    2017-06-01

    Oxidative stress (OS) and fluctuating asymmetry (FA) as risk markers for environmental stress are widely used to predict changes in the health and fitness of many animals exposed to pollutants. However, from the perspective of protecting declining amphibians, it remains to be verified which one would be a reliable indicator for amphibians exposed to long-term heavy metal pollution under natural conditions. In this study, the OS and FA of Bufo raddei exposed to natural heavy metal pollution were analyzed to determine which marker is more accurate for indicating heavy metal-induced stress. Three years of data were collected during the breeding season of B. raddei from Baiyin (BY), which has been mainly contaminated with Cu, Zn, Pb, and Cd compounds for a long period, and from Liujiaxia (LJX), which is a relatively unpolluted area. Unexpectedly, although significant accumulation of the four heavy metals was found in the kidney and liver of B. raddei from BY, the levels of superoxide dismutase, glutathione peroxidase, and malondialdehyde in these two organs were found to be irregular, with low repeatability in both BY and LJX. However, significant differences in the levels of FA were observed in B. raddei populations from these two areas over the past 3 years (P < 0.01). The degrees of FA in B. raddei populations from BY and LJX were assessed as degree 4 and 1, respectively. In short, this study suggested that FA was a more reliable and effective indicator than OS to monitor and predict long-term environmental stress on anuran amphibians.

  9. Testicular myxosporidiasis and ultrastructural characteristics of Myxobolus bufonis (Myxobolidae) infecting the Egyptian toad Bufo regularis (Bufonidae). A light and electron microscopic study.

    Science.gov (United States)

    Morsy, Kareem; Semmler, Margit; Al-Olayan, Ebtsam; Mehlhorn, Heinz

    2015-11-01

    The phylum Myxozoa comprises more than 2180 species, almost all of which are considered to be obligate parasites of aquatic fishes and amphibians. They are dangerous pathogens responsible for severe economic losses. From March to September 2014, 40 adult male Bufo regularis (Bufonidae) captured from different areas at Giza province, Egypt, were surveyed for myxosporean parasitic infection. Of these, 22 (55%) were infected by histozoic plasmodia, which produced spores after rupture belonging to Myxosporidia. The present investigation introduced a new data for the recorded parasite observed by light and transmission electron microscopy. The infection was diagnosed as large clusters of macroscopic plasmodia embedded in the testicular tissue causing distortion at the site of infection. The host reaction was manifested by the encapsulation of the plasmodia with a thick layer of connective tissue. Plasmodia were whitish in color, elliptical to ovoid in shape measuring 0.54 ± 0.2 (0.34-0.63) mm in diameter. The spores were subspherical, reaching 7.1 ± 0.2 (6.2-8.4) μm in length and 6.3 ± 0.2 (5.8-7.0) μm in width with two equal-sized polar capsules regularly arranged at the anterior pole of each spore. They were 3.4 ± 0.2 (3.0-4.2) μm in length and 1.9 ± 0.2 (1.6-2.4) in width with 6-8 turns of polar filaments. Ultrastructural analysis showed that the plasmodia were surrounded by a plasma membrane with numerous projections and pinocytotic channels extended toward the host cell. The generative cells and the different developmental stages were arranged at the periphery of the plasmodia while immature and mature spores were centrally arranged. Sporogenesis, capsulogenesis, valvogenesis, and spore maturation of the present parasite were also described.

  10. Development of Nuclear Microsatellite Loci and Mitochondrial Single Nucleotide Polymorphisms for the Natterjack Toad, Bufo (Epidalea) calamita (Bufonidae), Using Next Generation Sequencing and Competitive Allele Specific PCR (KASPar).

    Science.gov (United States)

    Faucher, Leslie; Godé, Cécile; Arnaud, Jean-François

    2016-01-01

    Amphibians are undergoing a major decline worldwide and the steady increase in the number of threatened species in this particular taxa highlights the need for conservation genetics studies using high-quality molecular markers. The natterjack toad, Bufo (Epidalea) calamita, is a vulnerable pioneering species confined to specialized habitats in Western Europe. To provide efficient and cost-effective genetic resources for conservation biologists, we developed and characterized 22 new nuclear microsatellite markers using next-generation sequencing. We also used sequence data acquired from Sanger sequencing to develop the first mitochondrial markers for KASPar assay genotyping. Genetic polymorphism was then analyzed for 95 toads sampled from 5 populations in France. For polymorphic microsatellite loci, number of alleles and expected heterozygosity ranged from 2 to 14 and from 0.035 to 0.720, respectively. No significant departures from panmixia were observed (mean multilocus F IS = -0.015) and population differentiation was substantial (mean multilocus F ST = 0.222, P < 0.001). From a set of 18 mitochondrial SNPs located in the 16S and D-loop region, we further developed a fast and cost-effective SNP genotyping method based on competitive allele-specific PCR amplification (KASPar). The combination of allelic states for these mitochondrial DNA SNP markers yielded 10 different haplotypes, ranging from 2 to 5 within populations. Populations were highly differentiated (G ST = 0.407, P < 0.001). These new genetic resources will facilitate future parentage, population genetics and phylogeographical studies and will be useful for both evolutionary and conservation concerns, especially for the set-up of management strategies and the definition of distinct evolutionary significant units. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Strong reproductive barriers in a narrow hybrid zone of West-Mediterranean green toads (Bufo viridis subgroup) with Plio-Pleistocene divergence

    Science.gov (United States)

    2010-01-01

    Background One key question in evolutionary biology deals with the mode and rate at which reproductive isolation accumulates during allopatric speciation. Little is known about secondary contacts of recently diverged anuran species. Here we conduct a multi-locus field study to investigate a contact zone between two lineages of green toads with an estimated divergence time of 2.7 My, and report results from preliminary experimental crosses. Results The Sicilian endemic Bufo siculus and the Italian mainland-origin B. balearicus form a narrow hybrid zone east of Mt. Etna. Despite bidirectional mtDNA introgression over a ca. 40 km North-South cline, no F1 hybrids could be found, and nuclear genomes display almost no admixture. Populations from each side of the contact zone showed depressed genetic diversity and very strong differentiation (FST = 0.52). Preliminary experimental crosses point to a slightly reduced fitness in F1 hybrids, a strong hybrid breakdown in backcrossed offspring (F1 x parental, with very few reaching metamorphosis) and a complete and early mortality in F2 (F1 x F1). Conclusion Genetic patterns at the contact zone are molded by drift and selection. Local effective sizes are reduced by the geography and history of the contact zone, B. balearicus populations being at the front wave of a recent expansion (late Pleistocene). Selection against hybrids likely results from intrinsic genomic causes (disruption of coadapted sets of genes in backcrosses and F2-hybrids), possibly reinforced by local adaptation (the ranges of the two taxa roughly coincide with the borders of semiarid and arid climates). The absence of F1 in the field might be due to premating isolation mechanisms. Our results, show that these lineages have evolved almost complete reproductive isolation after some 2.7 My of divergence, contrasting sharply with evidence from laboratory experiments that some anuran species may still produce viable F1 offspring after > 20 My of divergence. PMID

  12. A Single Transcriptome of a Green Toad (Bufo viridis) Yields Candidate Genes for Sex Determination and -Differentiation and Non-Anonymous Population Genetic Markers

    Science.gov (United States)

    Gerchen, Jörn F.; Reichert, Samuel J.; Röhr, Johannes T.; Dieterich, Christoph; Kloas, Werner

    2016-01-01

    Large genome size, including immense repetitive and non-coding fractions, still present challenges for capacity, bioinformatics and thus affordability of whole genome sequencing in most amphibians. Here, we test the performance of a single transcriptome to understand whether it can provide a cost-efficient resource for species with large unknown genomes. Using RNA from six different tissues from a single Palearctic green toad (Bufo viridis) specimen and Hiseq2000, we obtained 22,5 Mio reads and publish >100,000 unigene sequences. To evaluate efficacy and quality, we first use this data to identify green toad specific candidate genes, known from other vertebrates for their role in sex determination and differentiation. Of a list of 37 genes, the transcriptome yielded 32 (87%), many of which providing the first such data for this non-model anuran species. However, for many of these genes, only fragments could be retrieved. In order to allow also applications to population genetics, we further used the transcriptome for the targeted development of 21 non-anonymous microsatellites and tested them in genetic families and backcrosses. Eleven markers were specifically developed to be located on the B. viridis sex chromosomes; for eight markers we can indeed demonstrate sex-specific transmission in genetic families. Depending on phylogenetic distance, several markers, which are sex-linked in green toads, show high cross-amplification success across the anuran phylogeny, involving nine systematic anuran families. Our data support the view that single transcriptome sequencing (based on multiple tissues) provides a reliable genomic resource and cost-efficient method for non-model amphibian species with large genome size and, despite limitations, should be considered as long as genome sequencing remains unaffordable for most species. PMID:27232626

  13. Inferring the degree of incipient speciation in secondary contact zones of closely related lineages of Palearctic green toads (Bufo viridis subgroup)

    Science.gov (United States)

    Dufresnes, C; Bonato, L; Novarini, N; Betto-Colliard, C; Perrin, N; Stöck, M

    2014-01-01

    Reproductive isolation between lineages is expected to accumulate with divergence time, but the time taken to speciate may strongly vary between different groups of organisms. In anuran amphibians, laboratory crosses can still produce viable hybrid offspring >20 My after separation, but the speed of speciation in closely related anuran lineages under natural conditions is poorly studied. Palearctic green toads (Bufo viridis subgroup) offer an excellent system to address this question, comprising several lineages that arose at different times and form secondary contact zones. Using mitochondrial and nuclear markers, we previously demonstrated that in Sicily, B. siculus and B. balearicus developed advanced reproductive isolation after Plio-Pleistocene divergence (2.6 My, 3.3–1.9), with limited historic mtDNA introgression, scarce nuclear admixture, but low, if any, current gene flow. Here, we study genetic interactions between younger lineages of early Pleistocene divergence (1.9 My, 2.5–1.3) in northeastern Italy (B. balearicus, B. viridis). We find significantly more, asymmetric nuclear and wider, differential mtDNA introgression. The population structure seems to be molded by geographic distance and barriers (rivers), much more than by intrinsic genomic incompatibilities. These differences of hybridization between zones may be partly explained by differences in the duration of previous isolation. Scattered research on other anurans suggests that wide hybrid zones with strong introgression may develop when secondary contacts occur <2 My after divergence, whereas narrower zones with restricted gene flow form when divergence exceeds 3 My. Our study strengthens support for this rule of thumb by comparing lineages with different divergence times within the same radiation. PMID:24713825

  14. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans in Korea and China: population isolation and expansions as response to the ice ages

    Directory of Open Access Journals (Sweden)

    Amaël Borzée

    2017-11-01

    Full Text Available The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad (Bufo gargarizans from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.. Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a

  15. Phylogeographic and population insights of the Asian common toad (Bufo gargarizans) in Korea and China: population isolation and expansions as response to the ice ages.

    Science.gov (United States)

    Borzée, Amaël; Santos, Joana L; Sánchez-RamÍrez, Santiago; Bae, Yoonhyuk; Heo, Kyongman; Jang, Yikweon; Jowers, Michael Joseph

    2017-01-01

    The effects of ice ages on speciation have been well documented for many European and North American taxa. In contrast, very few studies have addressed the consequences of such environmental and topographical changes in North East Asian species. More precisely, the Korean Peninsula offers a unique model to assess patterns and processes of speciation as it hosts the northern- and eastern-most distribution limit of some widespread Asian taxa. Despite this, studies addressing phylogeographic patterns and population genetics in the peninsula and surrounding countries are few and studies for most families are lacking. Here we inferred the phylogenetic relationships of the common toad ( Bufo gargarizans ) from South Korea and their North East Asian counterpart populations, based on mitochondrial data. Korean B. gargarizans GenBank BLASTs matched few individuals from nearby China, but the presence of a Korean clade suggests isolation on the Korean Peninsula, previous to the last glacial maximum, linked to sea level resurgence. Molecular clock calibrations within this group were used to date the divergence between clades and their relationship to paleo-climatic events in the area. Lack of genetic structure among South Korean populations and strong homogeneity between the Korean and some Chinese localities suggest weak isolation and recent expansion. Geographical projection of continuous coalescent maximum-clade-credibility trees shows an original Chinese expansion towards the Korean Peninsula through the Yellow Sea circa two million years ago with colonisation events dating circa 800 thousand years ago (K. y. a.). Following this colonisation, the data point to outgoing Korean Peninsula dispersal events throughout different periods, towards the North through land, and West through land bridge formations over the Yellow Sea during sea level falls. In accordance, demographic analyses revealed a population expansion in the Koran Peninsula circa 300 K. y. a., likely attributed

  16. Measuring skin conductance over clothes.

    Science.gov (United States)

    Hong, Ki Hwan; Lee, Seung Min; Lim, Yong Gyu; Park, Kwang Suk

    2012-11-01

    We propose a new method that measures skin conductance over clothes to nonintrusively monitor the changes in physiological conditions affecting skin conductance during daily activities. We selected the thigh-to-thigh current path and used an indirectly coupled 5-kHz AC current for the measurement. While varying the skin conductance by the Valsalva maneuver method, the results were compared with the traditional galvanic skin response (GSR) measured directly from the fingers. Skin conductance measured using a 5-kHz current displayed a highly negative correlation with the traditional GSR and the current measured over clothes reflected the rate of change of the conductance of the skin beneath.

  17. Preventing Skin Cancer

    Centers for Disease Control (CDC) Podcasts

    2016-05-18

    A man and a woman talk about how they’ve learned to protect their skin from the sun over the years. .  Created: 5/18/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 5/18/2016.

  18. Monitoring pigmented skin lesions

    Science.gov (United States)

    Wallace, Vincent P.; Bamber, Jeffery C.; Ott, Robert J.; Crawford, Diane C.; Mortimer, Peter S.

    2002-06-01

    The rising incidence of skin cancer has led to an increase in the number of patients with skin lesions that require diagnosis, mostly using subjective visual examination. Successful treatment depends on early diagnosis. Unfortunately diagnostic accuracy, even by experts, can be as low as 56%; therefore, an accurate, objective diagnostic aid is greatly needed. Reflectance characteristics of pigmented skin lesions were documented to evaluate their diagnostic potential. Reflectance spectra in the wavelength range 320-1100nm were obtained from 260 lesions. Differences between spectra from benign and malignant lesions were utilized by extracting features with the best discriminating power. Discrimination was evaluated using two techniques: multivariate statistical analysis and artificial neural networks, using histology as the standard. Each technique was tested in a blind study and assessed in terms of its ability to diagnose new cases and compared to the clinical diagnosis. The artificial neural network achieved the best diagnostic performance for discriminating between malignant melanoma and benign nevi, having a sensitivity of 100% and a specificity of 65%. Utilization of visible and infrared techniques for monitoring skin lesions has lead to improvements in diagnostic accuracy. We conclude that these techniques are worthy of further development and evaluation in clinical practice as a screening tool.

  19. Stress and the skin.

    Science.gov (United States)

    Reich, A; Wójcik-Maciejewicz, A; Slominski, A T

    2010-04-01

    Emotional stress can affect, reveal or even exacerbate a number of skin disorders including psoriasis, atopic dermatitis, pruritus, alopecia areata, lichen planus, seborrheic dermatitis, rosacea or urticaria, although the direct pathophysiologic link between stress factors and cutaneous disease manifestation remains unclear. However, there is an increasing evidence that stress influences disease processes and contributes to the inflammation through modulating hypothalamic-pituitary-adrenal axis and releasing neuropeptides, neurotrophins, lymphokines and other chemical mediators from nerve endings and dermal cells. The central role in cellular skin reactivity to various stressors might be attributed to dermal mast cells, as they show close connections with sensory nerve endings and may release a huge number of proinflammatory mediators. However, many other cells also actively take part in skin response to stress. Although our knowledge is still not complete, one of the most distinct aspect is that the skin, endocrine, nervous and immune systems cannot longer be treated autonomously, but have to be considered as a large multidirectional complex of which interacting nature is still poorly understood.

  20. Examine Your Skin

    Medline Plus

    Full Text Available ... Melanoma Book Clinical Trials Download a Skin Self-Exam Card Download a Patient Navigation Card Events, Webinars & Videos Events, Webinars & Videos Melanoma Patient Video Events Host an Event Past Webinars Upcoming Webinars Volunteer Blog Blog Melanoma? The ...

  1. Parasites and the skin

    African Journals Online (AJOL)

    2009-06-11

    Jun 11, 2009 ... basin, the Caribbean and Latin America. It is transmitted by the bite of the phlebotomus sandfly. Dogs and rodents are the intermediate hosts. There are three forms of leishmaniasis: • cutaneous leishmaniasis, which is restricted to the skin and is seen more often in the old world, as seen in our patient.

  2. Skin Conditions during Pregnancy

    Science.gov (United States)

    ... the navel to pubic hair that darkens during pregnancy. Melasma: A common skin problem that causes brown to gray-brown patches on the face. Also known as “chloasma” or “mask of pregnancy.” Rectum: The last part of the digestive tract. ...

  3. Squamous cell skin cancer

    Science.gov (United States)

    ... squamous cell cancer include: Having light-colored skin, blue or green eyes, or blond or red hair Long-term, daily sun exposure (such as in people who work outside) Many severe sunburns early in life Older age Having had many x-rays Chemical exposure A weakened immune system, especially in ...

  4. Nomenclatural availability of the names applied to “varieties” of the green toad (Bufo viridis subgroup in the Italian territory, with emphasis on the variety lineata of Ninni (Anura: Bufonidae

    Directory of Open Access Journals (Sweden)

    Nicola Novarini

    2010-07-01

    Full Text Available Recent molecular investigations on Eurasian green toads led to the recognition of distinct lineages and to the establishment of new taxa within the former Bufo viridis; as a consequence, significant range-wide nomenclatural changes have been proposed, although some uncertainties remained on the available names applicable within the Italian territory. In order to contribute to clarify the matter, we evaluated, under the provisions of the International Code of Zoological Nomenclature, the nomenclatural availability of all the names that have been applied to infrasubspecific entities of the Bufo viridis subgroup within the Italian territory. We also provided a historical overview of the usage of all these names, as well as detailed information on the original material upon which the variety lineata of A.P. Ninni was established. Our analysis supports the view that only the names crucigera Eichwald, 1831 and balearica Boettger, 1880 are available, the former being however junior synonym of B. viridis Laurenti, 1768, whereas the names acutirostris and obtusirostris of Lessona, lineata of Ninni, concolor and maculata of Camerano, and nardoi of Paolucci, Fuhn and Bruno are all not available.

  5. Skin color independent assessment of aging using skin autofluorescence

    NARCIS (Netherlands)

    Koetsier, Marten; Nur, Erfan; Han Chunmao, [No Value; Lutgers, Helen L.; Links, Thera P.; Smit, Andries J.; Rakhorst, Gerhard; Graaff, Reindert

    2010-01-01

    Skin autofluorescence (AF) for the non-invasive assessment of the amount of accumulated tissue Advanced Glycation Endproducts (AGEs) increases with aging. In subjects with darker skin colors, measurements typically result in lower AF values than in subjects with fair skin colors, e. g. due to

  6. Tips for Relieving Dry Skin

    Science.gov (United States)

    ... skin include lactic acid, urea, hyaluronic acid, dimethicone, glycerin, lanolin, mineral oil, and petrolatum. Tip: Carry a ... using: Deodorant soaps Skin care products that contain alcohol, fragrance, retinoids, or alpha-hydroxy acid (AHA) Avoiding ...

  7. Candida infection of the skin

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000880.htm Candida infection of the skin To use the sharing features on this page, please enable JavaScript. Candida infection of the skin is a yeast infection ...

  8. 6 Common Cancers - Skin Cancer

    Science.gov (United States)

    ... involves the cells that produce the skin pigment melanin, which is responsible for skin and hair color. ... acted like a carrier pigeon to deliver a gene encoding a specific protein, called a T cell ...

  9. Skin aging and oxidative stress

    National Research Council Canada - National Science Library

    Ahsanuddin, Sayeeda; Lam, Minh; D. Baron, Elma

    2016-01-01

    .... Here, we review the critical role that oxidative stress plays in skin aging, including its effects on signaling pathways involved in skin matrix formation and degradation, proteasome activity, as well as DNA structure...

  10. Skin Detection of Animation Characters

    OpenAIRE

    Kazi Tanvir Ahmed Siddiqui; Abu Wasif

    2015-01-01

    The increasing popularity of animes makes it vulnerable to unwanted usages like copyright violations and pornography. That’s why, we need to develop a method to detect and recognize animation characters. Skin detection is one of the most important steps in this way. Though there are some methods to detect human skin color, but those methods do not work properly for anime characters. Anime skin varies greatly from human skin in color, texture, tone and in different kinds of lightin...

  11. Skin simulators for dermatological procedures

    OpenAIRE

    Wang, Xiaojie; Albahrani, Yasser; Pan, Michael; Levitt, Jacob

    2015-01-01

    Background: A variety of skin simulators are available on which to practice procedures; however, choice of a suboptimal substitute compromises realism and productive practice. Objective: Skin simulators for basic dermatological procedures are reviewed. Methods: The authors’ anecdotal experience with various skin simulators for different procedures is shared. Results: The following simulators are suggested:  an unripe banana ...

  12. Skin disorders affecting the feet

    African Journals Online (AJOL)

    Skin disorders on the feet can affect the glabrous skin on the dorsal aspects, or the thick skin on the plantar aspects, thereof, or both. Some can affect one foot, and others both of them. These diseases can be inflammatory, genetically inherited, infectious and neoplastic in origin. It is important to identify them and to.

  13. Maintaining Healthy Skin -- Part 1

    Science.gov (United States)

    ... problems. Tips for maintaining good skin care: Avoid soaps labeled "antibacterial" or "antimicrobial." These tend to reduce the skin's acidity, which acts as a protection from infection. Keep the skin clean and dry. Wash with soap and water daily, then rinse and dry thoroughly. ...

  14. Skin Pedagogies and Abject Bodies

    Science.gov (United States)

    Kenway, Jane; Bullen, Elizabeth

    2011-01-01

    How does the beauty industry "narrate the skin"? What does it teach women from different cultural groups about the female body? How does skin function as a site where female subjection and abjection are produced and reproduced? In this paper we examine the skin industry pointing to its extreme commodification of the female body and to the…

  15. Skin colorimetric parameters involved in skin age perception.

    Science.gov (United States)

    Puccetti, Germain; Nguyen, Tung; Stroever, Cristina

    2011-05-01

    Age perception is based on a number of facial attributes such as wrinkles, skin gravity effects, feature lines, and skin optical appearance. The colorimetric and optical diffusion properties of skin have been compared with the consumer interpretation of 'skin age' of cheek area pictures without wrinkles or feature lines. Controlled lighting images of skin were taken with the Visia CR. Skin sections from the cheek area were selected without eye region wrinkles or naso-labial lines for consumer interpretation. These same skin sections were analyzed for optical roughness and colorimetric parameters in the LCH color space, by distinguishing several roughness parameters according to their physical scale. Three main optical parameters of skin were found to influence the consumer's interpretation of skin 'visual age': the chroma (color saturation), lightness, and the local light-diffusing ability of skin. For the chroma and lightness, mainly large-scale inhomogeneities in the 0.8-2 cm(-1) range are taken into account by the consumer. Surprisingly, variations in the skin hue show a total absence of correlation with the consumer grading. © 2011 John Wiley & Sons A/S.

  16. Is skin penetration a determining factor in skin sensitization ...

    Science.gov (United States)

    Summary:Background. It is widely accepted that substances that cannot penetrate through the skin will not be sensitisers. Thresholds based on relevant physicochemical parameters such as a LogKow > 1 and a MW 1 is a true requirement for sensitisation.Methods. A large dataset of substances that had been evaluated for their skin sensitisation potential, together with measured LogKow values was compiled from the REACH database. The incidence of skin sensitisers relative to non-skin sensitisers below and above the LogKow = 1 threshold was evaluated. Results. 1482 substances with associated skin sensitisation outcomes and measured LogKow values were identified. 305 substances had a measured LogKow penetrate the stratum corneum is a key determinant of skin sensitisation potential and potency. Using the REACH data extracted to test out the validity of common assumptions in the skin sensitization AOP. Builds on trying to develop a proof of concept IATA

  17. Skin barrier in rosacea*

    Science.gov (United States)

    Addor, Flavia Alvim Sant'Anna

    2016-01-01

    Recent studies about the cutaneous barrier demonstrated consistent evidence that the stratum corneum is a metabolically active structure and also has adaptive functions, may play a regulatory role in the inflammatory response with activation of keratinocytes, angiogenesis and fibroplasia, whose intensity depends primarily on the intensity the stimulus. There are few studies investigating the abnormalities of the skin barrier in rosacea, but the existing data already show that there are changes resulting from inflammation, which can generate a vicious circle caused a prolongation of flare-ups and worsening of symptoms. This article aims to gather the most relevant literature data about the characteristics and effects of the state of the skin barrier in rosacea. PMID:26982780

  18. Skin contamination dosimeter

    Science.gov (United States)

    Hamby, David M [Corvallis, OR; Farsoni, Abdollah T [Corvallis, OR; Cazalas, Edward [Corvallis, OR

    2011-06-21

    A technique and device provides absolute skin dosimetry in real time at multiple tissue depths simultaneously. The device uses a phoswich detector which has multiple scintillators embedded at different depths within a non-scintillating material. A digital pulse processor connected to the phoswich detector measures a differential distribution (dN/dH) of count rate N as function of pulse height H for signals from each of the multiple scintillators. A digital processor computes in real time from the differential count-rate distribution for each of multiple scintillators an estimate of an ionizing radiation dose delivered to each of multiple depths of skin tissue corresponding to the multiple scintillators embedded at multiple corresponding depths within the non-scintillating material.

  19. CASE WITH SKIN ERUPTIONS

    Directory of Open Access Journals (Sweden)

    Shanthi Kumari

    2014-07-01

    Full Text Available A 50 years old male patient presented with fever, cough and dyspnea of 45 days duration and skin lesions of 20 days duration which he related to the local application of dettol after shaving. Examination revealed anemia, left basal pneumonitis and non pruritic, non tender, reddish purple nodular lesions over the face, behind the ear, chest and lower back (picture. There was no involvement of oral cavity or mucocutaneous junction. Peripheral nerves not thickened and there were no hypo-pigmented patches in the skin or organomegaly. Investigation revealed microcytic anemia, no abnormal cells in the peripheral smear. X ray showed left basal pneumonitis. Patient was treated with antibiotics and blood transfusion.

  20. Vibroacoustic Skin Diagnostics Modeling

    Directory of Open Access Journals (Sweden)

    Svetlana М. Yatsun

    2013-01-01

    Full Text Available The article deals with the mathematical modeling of biological diagnosis of complex heterogeneous structure (skin, using non-destructive control method. The mathematical model, describing interaction of the material with electrodynamic vibration generator and sensor system, controlling the propagation of small disturbances was developed. The influence of material model parameters on the spectrum in the course of the propagation of the surface disturbance

  1. Skin lesions in sadomasochism.

    Science.gov (United States)

    Sønderbo, K; Nyfors, A

    1986-01-01

    This paper presents the case of a 35-year-old man who consulted the department of venereology because of healing problems with some wounds caused by burning his skin perianally with cigarettes as part of a sexual satisfaction ritual. Knowledge of such lesions may be useful to physicians and social workers. Sadomasochism and 'offers' in the intimate-massage clinics in Copenhagen are surveyed.

  2. [Skin and menopause].

    Science.gov (United States)

    Bensaleh, H; Belgnaoui, F Z; Douira, L; Berbiche, L; Senouci, K; Hassam, B

    2006-12-01

    Important changes related to declining level of several hormones occur during menopause: vasomotor instability, bone loss, anxiety, sexual dysfunction, skin aging... Our objective was a review of the literature concerning the histological and clinical changes seen in post menopausal skin, and also an analysis of the effect of hormonal replacement therapy in slowing down the aging process. Decline in progesterone increases the impact of androgen on the sebaceous glands and hair. Decreased estrogen slows down mitotic activity in the epidermal basal layer, reduces the synthesis of collagen and contributes to thickening of the dermo-epidermal junction. This hypoestrogenemia may be spontaneously attenuated by local synthesis of oestradiol in peripheral target tissues according to the intracrine process. This new hormonal pattern is associated with skin atrophy, hyperseborrhea, increased pilosity on the cheeks and upper lip, loss of scalp hair, increase in degeneration of elastic tissue, atrophy and dryness of the vaginal mucosa. Estrogen treatment in post menopausal women has been shown to increase collagen content, dermal thickness and elasticity. Biophysical properties are also significantly improved for the parameters reflecting hydration and sebum secretion. However, numerous side effects such as increased incidence of cancer and cardiovascular morbidity limit the use of this treatment. So non hormonal alternatives are proposed. Laser and lifting remain the most important options.

  3. Lead and the skin

    Energy Technology Data Exchange (ETDEWEB)

    Allen, B.R.; Moore, M.R.; Hunter, J.A.A.

    1975-01-01

    The increasing use of lead will continue to give rise to problems of toxicity. Protective measures have resulted in florid lead poisoning becoming rare. Attention has recently turned to the possibility of prolonged exposure to low doses of lead causing morbidity in the absence of the classical clinical features of poisoning. Lead is absorbed mostly through the lungs and gastrointestinal tract. Some is also absorbed through the skin but with inorganic compounds the amount is small. Shortly after the most widely used compound, tetraethyl lead, was first manufactured, cases of toxicity began to occur. Manufacture was forbidden until plant design produced greater safety. Significant absorption can occur through the skin. The hazard to those handling leaded gasoline in a normal manner is probably small, mainly because 95 percent of a dose applied to the open skin surface evaporates. Hair has been used as a biopsy material to assess lead exposure. The biological effects of lead poisoning are discussed, including the synergistic effects of lead and agents provoking porphyria.

  4. SKIN RADIATION IN PANORAMIC

    Directory of Open Access Journals (Sweden)

    Herry Irawan

    2015-06-01

    Full Text Available Dental panoramic radiograph in Indonesia has been widely used. Modern diagnostic imaging equipment with minimum radiation is still very limited. One of the conditions in nuclear safety law, UU 10/1997, is an optimization of all radiation sources with DRL through skin dose measurements. In Indonesia, the national DRL has not been established yet, and there were no reports on the study of panoramic skin dose in Indonesia. The aim of this preliminary study was to obtain a panoramic skin dose radiation as reference to establish DRL in Indonesia. Panoramic radiographs of sixteen female and fifteen male patients, aged 4 – 48 years, were taken using the standard conventional method, with TLD chips attached in location groups. The chips were then read with the detector and integrator of BATAN, in high and low temperature condition at the same time. It was revealed that behind the right and left ear were the regions with the highest radiation dose received, followed by the back of the neck, left jaw, right jaw, and chin. The result of this study has shown the importance of DRL in Indonesia since the use of modern diagnostic imaging equipement that limits radiation dose to the minimum level is still very limited.

  5. Skin Cancer: NIH Research to Results

    Science.gov (United States)

    ... of this page please turn Javascript on. Feature: Skin Cancer NIH Research to Results Past Issues / Summer 2013 ... successful regression of advanced melanoma. Read More "Skin Cancer" Articles Skin Cancer Can Strike Anyone / Skin Cancer: Biology, Risk ...

  6. Treatment Options for Nonmelanoma Skin Cancer

    Science.gov (United States)

    ... Skin Cancer Skin Cancer Screening Research Skin Cancer Treatment (PDQ®)–Patient Version General Information About Skin Cancer ... Certain factors affect prognosis (chance of recovery) and treatment options. The prognosis (chance of recovery ) depends mostly ...

  7. Skin Cancer: Biology, Risk Factors & Treatment

    Science.gov (United States)

    ... turn Javascript on. Feature: Skin Cancer Skin Cancer: Biology, Risk Factors & Treatment Past Issues / Summer 2013 Table ... Articles Skin Cancer Can Strike Anyone / Skin Cancer: Biology, Risk Factors & Treatment / Timely Healthcare Checkup Catches Melanoma ...

  8. Characteristics of the Aging Skin.

    Science.gov (United States)

    Farage, Miranda A; Miller, Kenneth W; Elsner, Peter; Maibach, Howard I

    2013-02-01

    Although most researches into the changes in skin with age focus on the unwelcome aesthetic aspects of the aging skin, skin deterioration with age is more than a merely cosmetic problem. Although mortality from skin disease is primarily restricted to melanoma, dermatological disorders are ubiquitous in older people with a significant impact on quality of life. The structural and functional deterioration of the skin that occurs with age has numerous clinical presentations, ranging from benign but potentially excruciating disorders like pruritus to the more threatening carcinomas and melanomas. The degenerative changes that occur in the aging skin are increasingly understood at both the molecular and cellular level, facilitating a deeper understanding of the structural and functional deterioration that these changes produce. A loss of both function and structural stability in skin proceeds unavoidably as individuals age, which is the result of both intrinsic and extrinsic processes, which contribute simultaneously to a progressive loss of skin integrity. Intrinsic aging proceeds at a genetically determined pace, primarily caused by the buildup of damaging products of cellular metabolism as well as an increasing biological aging of the cells. Estrogen levels strongly influence skin integrity in women as well; falling levels in midlife, therefore, produce premature aging as compared with similarly aged men. Extrinsic insults from the environment add to the dermatological signs of aging. A deeper understanding of the physiological basis of skin aging will facilitate progress in the treatment of the unwelcome sequelae of aging skin, both cosmetic and pathogenic.

  9. Photothermal Radiometry for Skin Research

    Directory of Open Access Journals (Sweden)

    Perry Xiao

    2016-02-01

    Full Text Available Photothermal radiometry is an infrared remote sensing technique that has been used for skin and skin appendages research, in the areas of skin hydration, hydration gradient, skin hydration depth profiling, skin thickness measurements, skin pigmentation measurements, effect of topically applied substances, transdermal drug delivery, moisture content of bio-materials, membrane permeation, and nail and hair measurements. Compared with other technologies, photothermal radiometry has the advantages of non-contact, non-destructive, quick to make a measurement (a few seconds, and being spectroscopic in nature. It is also colour blind, and can work on any arbitrary sample surfaces. It has a unique depth profiling capability on a sample surface (typically the top 20 µm, which makes it particularly suitable for skin measurements. In this paper, we present a review of the photothermal radiometry work carried out in our research group. We will first introduce the theoretical background, then illustrate its applications with experimental results.

  10. Effects of seasonal variation on oxidative stress physiology in natural population of toad Bufo melanostictus; clues for analysis of environmental pollution.

    Science.gov (United States)

    Samanta, Luna; Paital, Biswaranjan

    2016-11-01

    Natural population of Bufo melanostictus in response to environmental cues shows several physiologic changes such as reproductive activity, hibernation, aestivation and metabolic depression in different seasons. We investigated the effects of seasonal fluctuations on oxidative stress (OS) physiology biomarkers, such as endogenous (ELPx) and induced (ILPx) lipid peroxidation, front-line redox regulatory enzymes (superoxide dismutase: SOD and catalase) and two non-enzyme antioxidant metabolites (ascorbic acid and reduced glutathione) in liver, gonad and cerebral hemisphere of toads collected from the Bhubaneswar area of India, where temperature fluctuates considerably rising to the highest in summer (∼46 °C) and being lowest in winter (<10 °C). Soil and air of the sampling site, although varying seasonally, were mostly found to be unpolluted, except for suspended particulate matter and respiratory particulate matter that were above recommended value. The magnitude of both ELPx and ILPx levels in most of the tissues, for example, ELPx in liver, cerebral hemisphere and ovary, and ILPx in liver of males and ovary, were found to be higher in rainy season in comparison to the other seasons. Nevertheless, levels of both ELPx and ILPx were low in testes in rainy season in comparison to the other two seasons. No correlation was observed between temperature and the studied OS parameters except a positive correlation with SOD and negative correlations with non-enzymatic small redox regulatory molecules in some selected tissues. Conversely, discriminant function analysis reveals a clear impact of the changing season on OS physiology of the toad. It implies that season considerably modulates OS physiology which be a reflection of the toads to abiotic pollutants alone and/or as results of metabolic changes under hibernation, aestivation and due to reproductive activities. Therefore, seasonal changes in OS physiological responses in poikilothermic models especially in toads

  11. PIGMENTOS EN LOS TESTÍCULOS DE CINCO ANFIBIOS ENDÉMICOS DE CUBA (Eleutherodactylus turquinensis, E. cuneatus, E. glamyrus, Bufo longinasus longinasus y B. longinasus cajalbanensis

    Directory of Open Access Journals (Sweden)

    Ana Sanz-Ochotorena

    2011-01-01

    Full Text Available Los vertebrados ectotérmicos pueden presentar un sistema pigmentario de función desconocida, aunque en algunos casos se han descrito los centros de melanomacrófagos con evidente función fagocítica; sin embargo, no es frecuente encontrar las gónadas pigmentadas en los anfibios anuros. El objetivo fundamental del presente trabajo es informar y analizar la presencia de pigmentos en los testículos de tres especies de ranas endémicas cubanas y en un sapo cubano, también endémico. Se estudiaron las especies Eleutherodactylus turquinensis, E. cuneatus, E. glamyrus y Bufo longinasus (subespecies B. l. longinasus y B. l. cajalbanensis, las cuales fueron colectadas en las zonas occidental y oriental de la Isla de Cuba. Los ejemplares se anestesiaron con éter una vez que se trasladaron al laboratorio. Se extrajeron las gónadas y se procesaron para microscopía óptica y en el caso de B. longinasus también para microscopía electrónica de transmisión. Los resultados indican una morfología de los testículos similar a otro anuros, se observó una organización cística de las células sexuales en los túbulos seminíferos y todos los ejemplares estaban en espermatogénesis total. Los testículos de todas las especies estudiadas mostraron una pigmentación oscura y abundante en la túnica albugínea y en el tejido intersticial. Se observaron muchos melanosomas. Se analiza en el trabajo que la causa de la fuerte pigmentación testicular pueda ser una respuesta a la contaminación, asimismo, se propone que los pigmentos son producidos por otro tipo celular quizás similar a los melanomacrófagos y no por melanocitos.

  12. Langerhans cells in porcine skin.

    Science.gov (United States)

    Nfon, Charles K; Dawson, Harry; Toka, Felix N; Golde, William T

    2008-12-15

    Langerhans cells (LCs) are resident dendritic cells (DCs) of skin and mucosal epithelium. The standard for identifying skin DCs as LCs is expression of langerin (CD207), a surface protein that mediates Birbeck granule (BG) formation upon internalization. Reports of BGs in porcine skin DC are contradictory, due to lack of langerin detection. Here, we present the sequence of porcine langerin/CD207, showing that the predicted porcine protein shares 75%/86% amino acid identity/similarity with human. Langerin mRNA was detected in porcine skin DCs by PCR and langerin protein was detected in both isolated skin DCs and skin sections by immunostaining. Approximately, 50-70% of skin DCs expressed langerin, demonstrating that the majority of porcine skin DCs are LCs. The full length sequence combined with the identification of antibodies reactive with porcine langerin, facilitates the study of LCs in swine, and advances the use of swine for studying skin diseases and infectious disease processes involving skin.

  13. Epidemiology of skin cancer.

    Science.gov (United States)

    Leiter, Ulrike; Eigentler, Thomas; Garbe, Claus

    2014-01-01

    Melanoma and nonmelanoma skin cancer (NMSC) are now the most common types of cancer in white populations. Both tumor entities show an increasing incidence rate worldwide but a stable or decreasing mortality rate. NMSC is the most common cancer in white-skinned individuals with a worldwide increasing incidence. NMSC is an increasing problem for health care services worldwide which causes significant morbidity. The rising incidence rates of NMSC are probably caused by a combination of increased exposure to ultraviolet (UV) or sun light, increased outdoor activities, changes in clothing style, increased longevity, ozone depletion, genetics and in some cases, immune suppression. An intensive UV exposure in childhood and adolescence was causative for the development of basal cell carcinoma (BCC) whereas for the etiology of SCC a chronic UV exposure in the earlier decades was accused. Cutaneous melanoma is the most rapidly increasing cancer in white populations, in the last 3 decades incidence rates have risen up to 5-fold. In 2008 melanoma was on place 5 in women and on place 8 in men of the most common solid tumor entities in Germany. The frequency of its occurrence is closely associated with the constitutive color of the skin, and the geographical zone. Changes in outdoor activities and exposure to sunlight during the past 50 years are an important factor for the increasing incidence of melanoma. Mortality rates of melanoma show a stabilization in the USA, Australia and also in European countries. In contrast to SCC, melanoma risk seems to be associated with an intermittent exposure to sunlight. Prevention campaigns aim on reducing incidence and achieving earlier diagnosis, which resulted in an ongoing trend toward thin melanoma since the last two decades. However, the impact of primary prevention measures on incidence rates of melanoma is unlikely to be seen in the near future, rather increasing incidence rates to 40-50/100,000 inhabitants/year should be expected in

  14. Climate change and skin.

    Science.gov (United States)

    Balato, N; Ayala, F; Megna, M; Balato, A; Patruno, C

    2013-02-01

    Global climate appears to be changing at an unprecedented rate. Climate change can be caused by several factors that include variations in solar radiation received by earth, oceanic processes (such as oceanic circulation), plate tectonics, and volcanic eruptions, as well as human-induced alterations of the natural world. Many human activities, such as the use of fossil fuel and the consequent accumulation of greenhouse gases in the atmosphere, land consumption, deforestation, industrial processes, as well as some agriculture practices are contributing to global climate change. Indeed, many authors have reported on the current trend towards global warming (average surface temperature has augmented by 0.6 °C over the past 100 years), decreased precipitation, atmospheric humidity changes, and global rise in extreme climatic events. The magnitude and cause of these changes and their impact on human activity have become important matters of debate worldwide, representing climate change as one of the greatest challenges of the modern age. Although many articles have been written based on observations and various predictive models of how climate change could affect social, economic and health systems, only few studies exist about the effects of this change on skin physiology and diseases. However, the skin is the most exposed organ to environment; therefore, cutaneous diseases are inclined to have a high sensitivity to climate. For example, global warming, deforestation and changes in precipitation have been linked to variations in the geographical distribution of vectors of some infectious diseases (leishmaniasis, lyme disease, etc) by changing their spread, whereas warm and humid environment can also encourage the colonization of the skin by bacteria and fungi. The present review focuses on the wide and complex relationship between climate change and dermatology, showing the numerous factors that are contributing to modify the incidence and the clinical pattern of many

  15. Skin biopsy in the diagnosis of neoplastic skin disease.

    Science.gov (United States)

    Harvey, Nathan Tobias; Chan, Jonathan; Wood, Benjamin Andrew

    2017-01-01

    Biopsy for diagnostic and therapeutic purposes is a central component in the management of neoplastic skin conditions. While the technical aspects of performing biopsies are familiar to most clinicians, a number of other aspects of the skin biopsy pathway are equally important. The objectives of this article are to provide general principles related to the biopsy of neoplastic skin conditions and offer practical advice on the approach to some common skin neoplasms. Careful attention to the selection of biopsy site and type, and communication of appropriate clinical details will ensure optimal patient care, minimising the chance of diagnostic errors with potentially serious medical and medico-legal consequences.

  16. Genetic structure and origin of a tetraploid toad species Bufo danatensis Pisanetz, 1978 (Amphibia, Bufonidae) from central Asia: Description of biochemical polymorphism and comparison of heterozygosity levels in diploid and tetraploid species

    Energy Technology Data Exchange (ETDEWEB)

    Mezhzherin, S.V.; Pisanets, E.M. [Schmalhausen Institute of Zoology, Kiev (Ukraine)

    1995-01-01

    Comparison of individual variation at 24 biochemical loci in members of the species complex of Palearctic green toads showed that the heterozygosity of the tetraploid species Bufo danatensis (H{sub obs} = 0.45) was significantly higher than that of the diploid species B. viridis, B. sp., and B. raddei (H{sub obs} = 0.009 - 0.103). Such difference can be explained only by a hybrid origin of the tetraploid species. Individual electrophoretic variability of the polyploid toad species is associated with an allelic variation that is manifested in constantly heterozygous spectra as the gene dosage effect. At the population level, this phenomenon found in Pamir toads is caused by irregular meiosis in founders of the population or by directional changes in gene regulation. Genotypic distributions in zones of contact of the diploid and tetraploid taxons demonstrate the possibility of restricted introgressive hybridization.

  17. Conservative procedures in skin reconstitution

    OpenAIRE

    Wollina, Uwe

    2005-01-01

    Skin exerts a number of essential protective functions ensuring homeostasis of the whole body. In the present review barrier function of skin and its expression of antimicrobial peptides are discussed. Barrier function is provided by the dynamic stratum corneum structure composed of lipids and corneocytes. Stratum corneum is a conditio sine qua non for terrestrial life. Impairment of barrier function can be due to injury and inflammatory skin diseases. Therapeutic options are discussed with s...

  18. Itchy lesions in pigmented skin.

    Science.gov (United States)

    Hung, Rachel; Ahmeen, Mahreen; Fleming, Ann; Hoque, Shamali

    2013-10-10

    A 37-year-old woman with type VI skin presented with 1-year history of pruritic lesions affecting her arms, chest and legs. The lesions were approximately 5 mm in diameter, annular and with a raised border. A skin biopsy was performed which showed a diagnosis of disseminated superficial actinic porokeratosis. Porokeratosis is an unusual presentation in pigmented skin and there are very limited reports of this occurrence in the literature.

  19. The future of skin metagenomics.

    Science.gov (United States)

    Mathieu, Alban; Vogel, Timothy M; Simonet, Pascal

    2014-01-01

    Metagenomics, the direct exploitation of environmental microbial DNA, is complementary to traditional culture-based approaches for deciphering taxonomic and functional microbial diversity in a plethora of ecosystems, including those related to the human body such as the mouth, saliva, teeth, gut or skin. DNA extracted from human skin analyzed by sequencing the PCR-amplified rrs gene has already revealed the taxonomic diversity of microbial communities colonizing the human skin ("skin microbiome"). Each individual possesses his/her own skin microbial community structure, with marked taxonomic differences between different parts of the body and temporal evolution depending on physical and chemical conditions (sweat, washing etc.). However, technical limitations due to the low bacterial density at the surface of the human skin or contamination by human DNA still has inhibited extended use of the metagenomic approach for investigating the skin microbiome at a functional level. These difficulties have been overcome in part by the new generation of sequencing platforms that now provide sequences describing the genes and functions carried out by skin bacteria. These methodological advances should help us understand the mechanisms by which these microorganisms adapt to the specific chemical composition of each skin and thereby lead to a better understanding of bacteria/human host interdependence. This knowledge will pave the way for more systemic and individualized pharmaceutical and cosmetic applications. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  20. Nicotinamide for skin cancer chemoprevention.

    Science.gov (United States)

    Damian, Diona L

    2017-08-01

    Nicotinamide (vitamin B 3 ) has a range of photoprotective effects in vitro and in vivo; it enhances DNA repair, reduces UV radiation-induced suppression of skin immune responses, modulates inflammatory cytokine production and skin barrier function and restores cellular energy levels after UV exposure. Pharmacological doses of nicotinamide have been shown to reduce actinic keratoses and nonmelanoma skin cancer incidence in high-risk individuals, making this a nontoxic and accessible option for skin cancer chemoprevention in this population. © 2017 The Australasian College of Dermatologists.

  1. Pathophysiological Study of Sensitive Skin

    National Research Council Canada - National Science Library

    Buhé, Virginie; Vié, Katell; Guéré, Christelle; Natalizio, Audrey; Lhéritier, Céline; Le Gall-Ianotto, Christelle; Huet, Flavien; Talagas, Matthieu; Lebonvallet, Nicolas; Marcorelles, Pascale; Carré, Jean-Luc; Misery, Laurent

    2016-01-01

    Sensitive skin is a clinical syndrome characterized by the occurrence of unpleasant sensations, such as pruritus, burning or pain, in response to various factors, including skincare products, water...

  2. Genetic differentiation between the black skinned and white skinned ...

    African Journals Online (AJOL)

    user

    2013-08-07

    Aug 7, 2013 ... The study investigates the genetic differentiation between the black skinned and white skinned ectotypes of the giant African land snails (Archachatina marginata) from Cross River State in Niger. Delta region of Nigeria. The random amplified polymorphic DNA (RAPD) technique was employed in this study.

  3. Genetic differentiation between the black skinned and white skinned ...

    African Journals Online (AJOL)

    The study investigates the genetic differentiation between the black skinned and white skinned ectotypes of the giant African land snails (Archachatina marginata) from Cross River State in Niger Delta region of Nigeria. The random amplified polymorphic DNA (RAPD) technique was employed in this study. Five (5) ...

  4. Double-Skin Facade

    DEFF Research Database (Denmark)

    Kalyanova, Olena

    Double-Skin Facades (DSF) are gaining popularity that, in fact, appears to be independent from sturdy critics of the concept in the past years. DSF buildings are being built in Europe and worldwide, DSF concept is being taught at schools of architecture and fully glazed office buildings are being...... favored by companies and their employees. To bring the reduction of energy use in these buildings application of suitable tools and methods is necessary to achieve successful design solutions. Earlier work on the topic of DSF modelling was examined from various publications. As a result, the main...... difficulties experienced by scientists when attempting to model DSF thermal and energy performance were examined. In addition, the lack of experimental studies and empirical validation of models was realized, many numerical models have not been empirically validated and most of them require an expert knowledge...

  5. Ablative skin resurfacing.

    Science.gov (United States)

    Chwalek, Jennifer; Goldberg, David J

    2011-01-01

    Ablative skin resurfacing has remained the gold standard for treating photodamage and acne scars since the development of the first CO(2) lasers. CO(2) and Er:YAG lasers emit infrared light, which targets water resulting in tissue contraction and collagen formation. The first ablative laser systems created significant thermal damage resulting in unacceptably high rates of scarring and prolonged healing. Newer devices, such as high-energy pulsed lasers and fractional ablative lasers, are capable of achieving significant improvements with fewer side effects and shorter recovery times. While ablative resurfacing has become safer, careful patient selection is still important to avoid post-treatment scarring, dyspigmentation, and infections. Clinicians utilizing ablative devices need to be aware of possible side effects in order to maximize results and patient satisfaction. This chapter reviews the background of ablative lasers including the types of ablative lasers, mechanism of action, indications for ablative resurfacing, and possible side effects. Copyright © 2011 S. Karger AG, Basel.

  6. [Radiotherapy of skin cancers].

    Science.gov (United States)

    Hennequin, C; Rio, E; Mahé, M-A

    2016-09-01

    The indications of radiotherapy for skin cancers are not clearly defined because of the lack of randomised trials or prospective studies. For basal cell carcinomas, radiotherapy frequently offers a good local control, but a randomized trial showed that surgery is more efficient and less toxic. Indications of radiotherapy are contra-indications of surgery for patients older than 60, non-sclerodermiform histology and occurring in non-sensitive areas. Adjuvant radiotherapy could be proposed to squamous cell carcinomas, in case of poor prognostic factors. Dose of 60 to 70Gy are usually required, and must be modulated to the size of the lesions. Adjuvant radiotherapy seems beneficial for desmoplastic melanomas but not for the other histological types. Prophylactic nodal irradiation (45 to 50Gy), for locally advanced tumours (massive nodal involvement), decreases the locoregional failure rate but do not increase survival. Adjuvant radiotherapy (50 to 56Gy) for Merckel cell carcinomas increases also the local control rate, as demonstrated by meta-analysis and a large epidemiological study. Nodal areas must be included, if there is no surgical exploration (sentinel lymph node dissection). Kaposi sarcomas are radiosensitive and could be treated with relatively low doses (24 to 30Gy). Also, cutaneous lymphomas are good indications for radiotherapy: B lymphomas are electively treated with limited fields. The role of total skin electron therapy for T-lymphomas is still discussed; but palliative radiotherapy is very efficient in case of cutaneous nodules. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  7. Oxidation events and skin aging

    NARCIS (Netherlands)

    Kammeyer, A.; Luiten, R. M.

    2015-01-01

    The rate of skin aging, or that of tissue in general, is determined by a variable predominance of tissue degeneration over tissue regeneration. This review discusses the role of oxidative events of tissue degeneration and aging in general, and for the skin in particular. The mechanisms involved in

  8. Mechanical behaviour of shark skin

    Indian Academy of Sciences (India)

    tribpo

    Materials and methods. Skins from adult Carcharias laticaudus were used for this study. The landed fish were transported in ice and the skins flayed using a dorsal longitudinal cut. Two locations. (figure 1) were sampled for histological and mechanical studies. Samples were cut in four directions—(i) parallel (to the long axis ...

  9. Menstrual cycle and skin reactivity

    DEFF Research Database (Denmark)

    Agner, T; Damm, P; Skouby, S O

    1991-01-01

    The hypothesis was tested that a cyclic variation exists in skin reactivity to irritant stimuli. Twenty-nine healthy women with regular menstrual cycles were challenged with sodium lauryl sulfate as an irritant patch test at day 1 and at days 9 through 11 of the menstrual cycle. The skin response...

  10. Introduction to skin cancer nursing.

    Science.gov (United States)

    Godsell, Gillian

    The incidence of skin cancer continues to increase annually and it is the most common cancer in the UK with over 100,000 cases each year. The treatment of skin cancer can involve many different disciplines including dermatology, plastic surgery, oncology, radiotherapy, ENT and maxillofacial and involves both adult and paediatric services in primary and secondary care. This article considers the many duties of a skin cancer clinical nurse specialist, and the increasing pressure such nurses are under. The skin cancer nurse specialist must liaise and work with the many different departments, and will be involved in the care of the patient with skin cancer from diagnosis throughout the pathway to discharge or death.

  11. [Early diagnosis of skin cancer].

    Science.gov (United States)

    Kolm, Isabell; Hofbauer, Günther; Braun, Ralph P

    2010-09-01

    The skin is the most affected organ by cancer. The incidence rates of skin cancer are steadily increasing, both for melanoma and non-melanoma skin cancers (squamous cell carcinoma, basal cell carcinoma). Over 90 % of the death cases from skin cancers attribute to melanoma. Survival from melanoma is strongly related to tumour thickness. Therefore early detection is the most important step to improve prognosis. In the last years a number of new non invasive techniques for the early diagnosis of melanoma have been developed which are superior to the naked eye examination. In this overview article we present some non-invasive diagnostic techniques like total body photography, digital dermoscopy and confocal microscopy which in addition to dermoscopy assist the dermatologist in differentiating nevi from early melanomas.Non-melanoma skin cancer can be prevented by accurate sun protection. Early squamous cell carcinomas and basal cell carcinomas can be treated either invasively or non-invasively with excellent prognosis.

  12. Common skin conditions during pregnancy.

    Science.gov (United States)

    Tunzi, Marc; Gray, Gary R

    2007-01-15

    Common skin conditions during pregnancy generally can be separated into three categories: hormone-related, preexisting, and pregnancy-specific. Normal hormone changes during pregnancy may cause benign skin conditions including striae gravidarum (stretch marks); hyperpigmentation (e.g., melasma); and hair, nail, and vascular changes. Preexisting skin conditions (e.g., atopic dermatitis, psoriasis, fungal infections, cutaneous tumors) may change during pregnancy. Pregnancy-specific skin conditions include pruritic urticarial papules and plaques of pregnancy, prurigo of pregnancy, intrahepatic cholestasis of pregnancy, pemphigoid gestationis, impetigo herpetiformis, and pruritic folliculitis of pregnancy. Pruritic urticarial papules and plaques of pregnancy are the most common of these disorders. Most skin conditions resolve postpartum and only require symptomatic treatment. However, there are specific treatments for some conditions (e.g., melasma, intrahepatic cholestasis of pregnancy, impetigo herpetiformis, pruritic folliculitis of pregnancy). Antepartum surveillance is recommended for patients with intrahepatic cholestasis of pregnancy, impetigo herpetiformis, and pemphigoid gestationis.

  13. Periostin in Skin Tissue Skin-Related Diseases

    Directory of Open Access Journals (Sweden)

    Yukie Yamaguchi

    2014-01-01

    Recently, periostin—a matricellular protein—has been highlighted for its pivotal functions in the skin. Analysis of periostin null mice has revealed that periostin contributes to collagen fibrillogenesis, collagen cross-linking, and the formation of ECM meshwork via interactions with other ECM components. Periostin expression is enhanced by mechanical stress or skin injury; this is indicative of the physiologically protective functions of periostin, which promotes wound repair by acting on keratinocytes and fibroblasts. Along with its physiological functions, periostin plays pathogenic roles in skin fibrosis and chronic allergic inflammation. In systemic sclerosis (SSc patients, periostin levels reflect the severity of skin fibrosis. Periostin null mice have shown reduced skin fibrosis in a bleomycin-induced SSc mouse model, indicating a key role of periostin in fibrosis. Moreover, in atopic dermatitis (AD, attenuated AD phenotype has been observed in periostin null mice in a house dust mite extract-induced AD mouse model. Th2 cytokine-induced periostin acts on keratinocytes to produce inflammatory cytokines that further enhance the Th2 response, thereby sustaining and amplifying chronic allergic inflammation. Thus, periostin is deeply involved in the pathogenesis of AD and other inflammation-related disorders affecting the skin. Understanding the dynamic actions of periostin would be key to dissecting pathogenesis of skin-related diseases and to developing novel therapeutic strategies.

  14. Laser speckle and skin cancer: skin roughness assessment

    Science.gov (United States)

    Lee, Tim K.; Tchvialeva, Lioudmila; Zeng, Haishan; McLean, David I.; Lui, Harvey

    2009-10-01

    Incidence of skin cancer has been increasing rapidly since the last few decades. Non-invasive optical diagnostic tools may improve the diagnostic accuracy. In this paper, skin structure, skin cancer statistics and subtypes of skin cancer are briefly reviewed. Among the subtypes, malignant melanoma is the most aggressive and dangerous; early detection dramatically improves the prognosis. Therefore, a non-invasive diagnostic tool for malignant melanoma is especially needed. In addition, in order for the diagnostic tool to be useful, it must be able to differentiate melanoma from common skin conditions such as seborrheic keratosis, a benign skin disease that resembles melanoma according to the well known clinical-assessment ABCD rule. The key diagnostic feature between these two diseases is surface roughness. Based on laser speckle contrast, our research team has recently developed a portable, optical, non-invasive, in-vivo diagnostic device for quantifying skin surface roughness. The methodology of our technique is described in details. Examining the preliminary data collected in a pilot clinical study for the prototype, we found that there was a difference in roughness between melanoma and seborrheic keratosis. In fact, there was a perfect cutoff value for the two diseases based on our initial data.

  15. Survey of skin pigmentation of yellow-skinned broiler chickens.

    Science.gov (United States)

    Sirri, F; Petracci, M; Bianchi, M; Meluzzi, A

    2010-07-01

    The appearance of whole carcass and skin-on cut-up products is an important attribute that deeply affects the consumer's choice. Skin pigmentation is affected mainly by genetics, concentration and dietary source of pigments, health status of the birds, and scalding-plucking conditions during slaughtering, although other factors might play an important role. Retailers request batches of broiler chicken carcasses characterized by uniform skin pigmentation to be sold as whole carcass or parts. The aim of this study was to evaluate the variability of skin color of yellow-skinned broilers reared under intensive conditions. For the study, a total of 2,300 medium size broiler chickens (2,300 to 2,500 g of live weight) from 23 flocks (100 birds/flock; n = 12 flocks of males and n = 11 flocks of females; n = 12 flocks of Ross 508 and n = 11 flocks of Ross 308) were randomly selected in a single slaughterhouse. The color measurements were carried out on both breast and thigh pterylae as well as on shank skin adopting the L* a* b* system and using a Minolta colorimeter CR 300. The overall range in measured yellowness (b*) was fairly large for all skin color measurement positions. For breast, a mean value of 22.77 (SD = 5.12) was observed, with values ranging from 7.45 to 39.12. Average values of thigh and shank were 20.23 (SD = 5.02; range 1.99 to 37.82) and 53.99 (SD = 8.13; range 24.22 to 78.65), respectively. A higher skin yellowness was observed in females in all body parts as well as in Ross 308. Yellowness values of breast and thigh were significantly correlated (r = 0.85; P < 0.01), suggesting that the color evaluation may be carried out only on one measurement position of the skin.

  16. How complex is the Bufo bufo species group?

    NARCIS (Netherlands)

    Arntzen, J.W.; Recuero, E.; Canestrelli, D.; Martínez-Solano, I.

    2013-01-01

    Species delineation remains one of the most challenging tasks in the study of biodiversity, mostly owing to the application of different species concepts, which results in contrasting taxonomic arrangements. This has important practical consequences, since species are basic units in fields like

  17. Optical coherence tomography for imaging of skin and skin diseases

    DEFF Research Database (Denmark)

    Mogensen, Mette; Thrane, Lars; Jørgensen, Thomas Martini

    2009-01-01

    , as have many diseases. The method can provide accurate measures of epidermal and nail changes in normal tissue. Skin cancer and other tumors, as well as inflammatory diseases, have been studied and good agreement found between OCT images and histopathological architecture. OCT also allows noninvasive...... monitoring of morphologic changes in skin diseases and may have a particular role in the monitoring of medical treatment of nonmelanoma skin cancer. The technology is however still evolving and continued technological development will necessitate an ongoing evaluation of its diagnostic accuracy. Several...

  18. How to Prevent Skin Conditions in Athletes

    Science.gov (United States)

    ... care / hair loss Injured skin Nail care Anti-aging skin care Kids’ zone Video ... are at an increased risk of skin infections, which can have serious consequences. To help prevent infections, athletes, coaches and athletic ...

  19. Integral skin electrode for electrocardiography is expendable

    Science.gov (United States)

    1966-01-01

    Inexpensive, expendable skin electrode for use in electrocardiography combines an electrical contact, conductive paste, and a skin-attachment adhesive. Application of the electrode requires only degreasing of the skin area.

  20. Sun’s effect on skin

    Science.gov (United States)

    The skin uses sunlight to help manufacture vitamin D, which is important for normal bone formation. But sometimes its ultraviolet light can be ... the pigment melanin. Melanin protects skin from the sun's ultraviolet rays, which can burn the skin, and ...

  1. Normal and abnormal skin color.

    Science.gov (United States)

    Ortonne, J P

    2012-12-01

    The varieties of normal skin color in humans range from people of "no color" (pale white) to "people of color" (light brown, dark brown, and black). Skin color is a blend resulting from the skin chromophores red (oxyhaemoglobin), blue (deoxygenated haemoglobin), yellow-orange (carotene, an exogenous pigment), and brown (melanin). Melanin, however, is the major component of skin color ; it is the presence or absence of melanin in the melanosomes in melanocytes and melanin in keratinocytes that is responsible for epidermal pigmentation, and the presence of melanin in macrophages or melanocytes in the dermis that is responsible for dermal pigmentation. Two groups of pigmentary disorders are commonly distinguished: the disorders of the quantitative and qualitative distribution of normal pigment and the abnormal presence of exogenous or endogenous pigments in the skin. The first group includes hyperpigmentations, which clinically manifest by darkening of the skin color, and leukodermia, which is characterized by lightening of the skin. Hypermelanosis corresponds to an overload of melanin or an abnormal distribution of melanin in the skin. Depending on the color, melanodermia (brown/black) and ceruloderma (blue/grey) are distinguished. Melanodermia correspond to epidermal hypermelanocytosis (an increased number of melanocytes) or epidermal hypermelanosis (an increase in the quantity of melanin in the epidermis with no modification of the number of melanocytes). Ceruloderma corresponds to dermal hypermelanocytosis (abnormal presence in the dermis of cells synthesizing melanins) ; leakage in the dermis of epidermal melanin also exists, a form of dermal hypermelanosis called pigmentary incontinence. Finally, dyschromia can be related to the abnormal presence in the skin of a pigment of exogenous or endogenous origin. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  2. [Normal and abnormal skin color].

    Science.gov (United States)

    Ortonne, J-P

    2012-11-01

    The varieties of normal skin color in humans range from people of "no color" (pale white) to "people of color" (light brown, dark brown, and black). Skin color is a blend resulting from the skin chromophores red (oxyhaemoglobin), blue (deoxygenated haemoglobin), yellow-orange (carotene, an exogenous pigment), and brown (melanin). Melanin, however, is the major component of skin color ; it is the presence or absence of melanin in the melanosomes in melanocytes and melanin in keratinocytes that is responsible for epidermal pigmentation, and the presence of melanin in macrophages or melanocytes in the dermis that is responsible for dermal pigmentation. Two groups of pigmentary disorders are commonly distinguished: the disorders of the quantitative and qualitative distribution of normal pigment and the abnormal presence of exogenous or endogenous pigments in the skin. The first group includes hyperpigmentations, which clinically manifest by darkening of the skin color, and leukodermia, which is characterized by lightening of the skin. Hypermelanosis corresponds to an overload of melanin or an abnormal distribution of melanin in the skin. Depending on the color, melanodermia (brown/black) and ceruloderma (blue/grey) are distinguished. Melanodermia correspond to epidermal hypermelanocytosis (an increased number of melanocytes) or epidermal hypermelanosis (an increase in the quantity of melanin in the epidermis with no modification of the number of melanocytes). Ceruloderma correspond to dermal hypermelanocytosis (abnormal presence in the dermis of cells synthesizing melanins) ; leakage in the dermis of epidermal melanin also exists, a form of dermal hypermelanosis called pigmentary incontinence. Finally, dyschromia can be related to the abnormal presence in the skin of a pigment of exogenous or endogenous origin. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  3. Skin biopsy in the diagnosis of inflammatory skin disease.

    Science.gov (United States)

    Harvey, Nathan Tobias; Chan, Jonathan; Wood, Benjamin Andrew

    2017-01-01

    Most non-neoplastic skin conditions are readily diagnosed by a combination of clinical history and examination, but in a small number of cases, biopsy for histopathology and other laboratory investigations can be invaluable tools. Close attention to communication of appropriate clinical details, selection of biopsy site and biopsy technique have a marked impact on the diagnostic yield of this procedure. The objectives of this article are to provide general principles related to the biopsy of non-neoplastic skin conditions and offer practical advice on the approach to some common skin conditions. In this article, we discuss a number of general principles that will ensure maximum benefits can be achieved when a biopsy is per-formed for the diagnosis of non-neoplastic skin disease.

  4. About Skin-to-Skin Care (Kangaroo Care)

    Science.gov (United States)

    ... skin care, also called kangaroo care. What is Kangaroo Care? Kangaroo care was developed in South America ... between their warm breasts. The surprising benefits of kangaroo care for the infant include: Warmth Stability of ...

  5. Skin temperature during sunbathing--relevance for skin cancer

    DEFF Research Database (Denmark)

    Petersen, Bibi; Philipsen, Peter Alshede; Wulf, Hans Christian

    2014-01-01

    It has been found that exposure to heat and infrared radiation (IR) can be carcinogenic, and that a combination of ultraviolet radiation (UVR) and IR possibly amplifies carcinogenesis. To investigate how the skin temperature is affected by sunbathing, we measured the skin temperature on 20 healthy...... volunteers over 6 days' sun holiday in Egypt. Temperatures were measured with an infrared thermometer gun at 8 skin sites on the volunteers while they were indoors in the morning and when sunbathing during the day. Skin temperatures were higher during sunbathing (33.5 °C ± 2.1 °C) (mean ± SD) than when...... by activation of the heat shock response, is likely to contribute to the immediate and delayed effects of UV in a way that has to be found out in future studies....

  6. On the novel action of melanolysis by a leaf extract of Aloe vera and its active ingredient aloin, potent skin depigmenting agents.

    Science.gov (United States)

    Ali, Sharique A; Galgut, Jyoti M; Choudhary, Ram K

    2012-05-01

    The present study was carried out to investigate the effects of an Aloe vera leaf extract, along with its standard active ingredient aloin, on the isolated tail melanophores of Bufo melanostictus tadpoles, which are a type of disguised smooth muscle cells offering excellent in vitro opportunities for studying the effects of pharmacological and pharmaceutical agents. It was found that the leaf extract of A. vera and its active ingredient aloin induced powerful, dose-dependent, physiologically significant melanin aggregating effects in the isolated tail melanophores of B. melanostictus similar to those of adrenaline per se. These preliminary findings clearly demonstrate that the extract of A. vera and its active ingredient aloin cause melanin aggregation leading to skin lightening via alpha adrenergic receptor stimulation. The present study opens new vistas for the use of A. vera regarding its clinical application as a new nontoxic melanolytic agent for the treatment of hyperpigmentation. Georg Thieme Verlag KG Stuttgart · New York.

  7. Skin Barrier Function and Allergens

    DEFF Research Database (Denmark)

    Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

    2016-01-01

    The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...... and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due...

  8. Human reconstructed skin xenografts on mice to model skin physiology.

    Science.gov (United States)

    Salgado, Giorgiana; Ng, Yi Zhen; Koh, Li Fang; Goh, Christabelle S M; Common, John E

    Xenograft models to study skin physiology have been popular for scientific use since the 1970s, with various developments and improvements to the techniques over the decades. Xenograft models are particularly useful and sought after due to the lack of clinically relevant animal models in predicting drug effectiveness in humans. Such predictions could in turn boost the process of drug discovery, since novel drug compounds have an estimated 8% chance of FDA approval despite years of rigorous preclinical testing and evaluation, albeit mostly in non-human models. In the case of skin research, the mouse persists as the most popular animal model of choice, despite its well-known anatomical differences with human skin. Differences in skin biology are especially evident when trying to dissect more complex skin conditions, such as psoriasis and eczema, where interactions between the immune system, epidermis and the environment likely occur. While the use of animal models are still considered the gold standard for systemic toxicity studies under controlled environments, there are now alternative models that have been approved for certain applications. To overcome the biological limitations of the mouse model, research efforts have also focused on "humanizing" the mice model to better recapitulate human skin physiology. In this review, we outline the different approaches undertaken thus far to study skin biology using human tissue xenografts in mice and the technical challenges involved. We also describe more recent developments to generate humanized multi-tissue compartment mice that carry both a functioning human immune system and skin xenografts. Such composite animal models provide promising opportunities to study drugs, disease and differentiation with greater clinical relevance. Copyright © 2017 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  9. (Bufo regularis) ES AJIBOLA*, A

    African Journals Online (AJOL)

    Daniel Owu

    percentage twitch height depression a finding which suggested that both effects could be mediated through the same receptor. Tetanic fade or Wendesky inhibition is the failure of a muscle to sustain tension during high frequency motor nerve stimulation in the presence of a non depolarizing neuromuscular blocking drug.

  10. Interaction of dermatologically relevant nanoparticles with skin cells and skin

    Directory of Open Access Journals (Sweden)

    Annika Vogt

    2014-12-01

    Full Text Available The investigation of nanoparticle interactions with tissues is complex. High levels of standardization, ideally testing of different material types in the same biological model, and combinations of sensitive imaging and detection methods are required. Here, we present our studies on nanoparticle interactions with skin, skin cells, and biological media. Silica, titanium dioxide and silver particles were chosen as representative examples for different types of skin exposure to nanomaterials, e.g., unintended environmental exposure (silica versus intended exposure through application of sunscreen (titanium dioxide or antiseptics (silver. Because each particle type exhibits specific physicochemical properties, we were able to apply different combinations of methods to examine skin penetration and cellular uptake, including optical microscopy, electron microscopy, X-ray microscopy on cells and tissue sections, flow cytometry of isolated skin cells as well as Raman microscopy on whole tissue blocks. In order to assess the biological relevance of such findings, cell viability and free radical production were monitored on cells and in whole tissue samples. The combination of technologies and the joint discussion of results enabled us to look at nanoparticle–skin interactions and the biological relevance of our findings from different angles.

  11. Discovery – Preventing Skin Cancer

    Science.gov (United States)

    Cancer research includes stopping cancer before it spreads. NCI funded the development of the Melanoma Risk Assessment Tool and the ABC method. Both help to diagnose high-risk patients and prevent melanoma earlier in the fight against skin cancer.

  12. Drugs Approved for Skin Cancer

    Science.gov (United States)

    This page lists cancer drugs approved by the Food and Drug Administration (FDA) for skin cancer. The list includes generic names and brand names. The drug names link to NCI's Cancer Drug Information summaries.

  13. Abnormally dark or light skin

    Science.gov (United States)

    Over-the-counter and prescription creams are available for lightening the skin. Hydroquinone combined with tretinoin is an effective combination. If you use these creams, follow instructions carefully, and don't use one ...

  14. Moisturizers: Options for Softer Skin

    Science.gov (United States)

    ... producing glands become less active. To keep your skin soft and well-hydrated, choose an oil-based moisturizer that contains petrolatum as the base, along with antioxidants or alpha hydroxy acids to combat wrinkles. These ...

  15. Insulin Resistance and Skin Diseases

    Directory of Open Access Journals (Sweden)

    Maddalena Napolitano

    2015-01-01

    Full Text Available In medical practice, almost every clinician may encounter patients with skin disease. However, it is not always easy for physicians of all specialties to face the daily task of determining the nature and clinical implication of dermatologic manifestations. Are they confined to the skin, representing a pure dermatologic event? Or are they also markers of internal conditions relating to the patient’s overall health? In this review, we will discuss the principal cutaneous conditions which have been linked to metabolic alterations. Particularly, since insulin has an important role in homeostasis and physiology of the skin, we will focus on the relationships between insulin resistance (IR and skin diseases, analyzing strongly IR-associated conditions such as acanthosis nigricans, acne, and psoriasis, without neglecting emerging and potential scenarios as the ones represented by hidradenitis suppurativa, androgenetic alopecia, and hirsutism.

  16. Skin Cancers of the Feet

    Science.gov (United States)

    ... Feature Article Library Getting Your Practice Online Member Logo State Laws & Regulations Anti-Fee Discrimination Any Willing ... of extreme importance for patients for the early detection of both benign and malignant skin tumors. Learn ...

  17. Reference Values of Skin Autofluorescence

    NARCIS (Netherlands)

    Koetsier, M.; Lutgers, H. L.; de Jonge, C.; Links, T. P.; Smit, A. J.; Graaff, R.

    Background: Skin autofluorescence (AF) as measured with the AGE Reader (DiagnOptics Technologies, Groningen, The Netherlands) is a noninvasive prognostic marker in diabetes mellitus and other diseases with increased cardiovascular risk. This study provides reference values of healthy Caucasian

  18. Flu Vaccine Skin Patch Tested

    Science.gov (United States)

    ... Past Issues Subscribe September 2017 Print this issue Flu Vaccine Skin Patch Tested En español Send us ... Each year, millions of people nationwide catch the flu. The best way to protect yourself is to ...

  19. Radiation Therapy for Skin Cancer

    Science.gov (United States)

    ... make sure they are safe to use during radiation therapy. • Eat a balanced diet. If food tastes ... your fluid intake. • Treat the skin exposed to radiation with special care. Stay out of the sun, ...

  20. Skin anti-aging strategies

    National Research Council Canada - National Science Library

    Ganceviciene, Ruta; Liakou, Aikaterini I; Theodoridis, Athanasios; Makrantonaki, Evgenia; Zouboulis, Christos C

    2012-01-01

    .... Because of the fact that skin health and beauty is considered one of the principal factors representing overall "well-being" and the perception of "health" in humans, several anti-aging strategies...

  1. Clinical utility of skin karyotype

    OpenAIRE

    Dorfman, Luiza E.; Silva, Agnes F. R. P.; Paskulin, Giorgio A.; Rosa, Rafael F. M.; Zen, Paulo R. G.

    2015-01-01

    ABSTRACTWe report the case of a patient with Patau syndrome, diagnosed by skin karyotype, emphasizing the applications and importance of this test. The pregnancy morphology ultrasound showed face defects and of central nervous system and heart chambers asymmetry. In the postnatal evaluation it was identified microcephaly, single central nostril, and other malformations. We performed skin karyotype that resulted in full trisomy 13. Our report highlights the possibility of performing karyotype ...

  2. UV Clothing and Skin Cancer

    OpenAIRE

    Tarbuk, Anita; Grancarić, Ana Marija; Šitum, Mirna; Martinis, Mladen

    2010-01-01

    Skin cancer incidence in Croatia is steadily incresing in spite of public and govermental permanently measurements. It is clear that will soon become a major public health problem. The primary cause of skin cancer is believed to be a long exposure to solar ultraviolet (UV) radiation. The future designers of UV protective materials should be able to block totally the ultraviolet radiation. The aim of this paper is to present results of measurements concerning UV protecting ability of garments ...

  3. Granulomatous lesions of the skin

    Directory of Open Access Journals (Sweden)

    K Gautam

    2011-10-01

    Full Text Available Background: Granulomatous skin lesions often present as a diagnostic challenge to dermatopathologists due to various modes of presentation and identical histological picture produced by several causes. The aim of the study was to study different granulomatous skin lesions and to determine the relative frequency, the level of clinicopathologic concordance and to compare our results with those of other workers. Materials and Methods: A retrospective analysis of skin biopsies received over a period of two years from January 2007 to December 2008; was performed, and cases of granulomatous dermatitis reported on histopathological examination were reviewed along with special stains. Results: Out of a total of 1590 skin biopsies 106 (6.67% cases were found to have a granulomatous reaction. It was common in males (63.21% with most occurring in the fourth to fifth decades. Majority of cases (79 cases, 74.5% were categorized as infectious granulomatous lesions with predominance of leprosy (63 cases, 79.7% followed by tuberculosis (6 cases, 7.6%. An overall clinicopathologic concordance was seen in 97% of cases of leprosy. Conclusion: In this study leprosy is the most common cause of granulomatous skin lesions. It can be concluded that histopathology plays an important role in classification of leprosy, and in diagnosis and management of a variety of granulomatous skin diseases. Special stains play a supportive role in infectious granulomas. Keywords: Granulomatous skin lesion; Leprosy; Skin biopsy DOI: http://dx.doi.org/10.3126/jpn.v1i2.5397 JPN 2011; 1(2: 81-86

  4. Systemic antioxidants and skin health.

    Science.gov (United States)

    Nguyen, Gloria; Torres, Abel

    2012-09-01

    Most dermatologists agree that antioxidants help fight free radical damage and can help maintain healthy skin. They do so by affecting intracellular signaling pathways involved in skin damage and protecting against photodamage, as well as preventing wrinkles and inflammation. In today's modern world of the rising nutraceutical industry, many people, in addition to applying topical skin care products, turn to supplementation of the nutrients missing in their diets by taking multivitamins or isolated, man-made nutraceuticals, in what is known as the Inside-Out approach to skin care. However, ingestion of large quantities of isolated, fragmented nutrients can be harmful and is a poor representation of the kind of nutrition that can be obtained from whole food sources. In this comprehensive review, it was found that few studies on oral antioxidants benefiting the skin have been done using whole foods, and that the vast majority of current research is focused on the study of compounds in isolation. However, the public stands to benefit greatly if more research were to be devoted toward the impact that physiologic doses of antioxidants (obtained from fruits, vegetables, and whole grains) can have on skin health, and on health in general.

  5. UV Radiation and the Skin

    Directory of Open Access Journals (Sweden)

    Timothy Scott

    2013-06-01

    Full Text Available UV radiation (UV is classified as a “complete carcinogen” because it is both a mutagen and a non-specific damaging agent and has properties of both a tumor initiator and a tumor promoter. In environmental abundance, UV is the most important modifiable risk factor for skin cancer and many other environmentally-influenced skin disorders. However, UV also benefits human health by mediating natural synthesis of vitamin D and endorphins in the skin, therefore UV has complex and mixed effects on human health. Nonetheless, excessive exposure to UV carries profound health risks, including atrophy, pigmentary changes, wrinkling and malignancy. UV is epidemiologically and molecularly linked to the three most common types of skin cancer, basal cell carcinoma, squamous cell carcinoma and malignant melanoma, which together affect more than a million Americans annually. Genetic factors also influence risk of UV-mediated skin disease. Polymorphisms of the melanocortin 1 receptor (MC1R gene, in particular, correlate with fairness of skin, UV sensitivity, and enhanced cancer risk. We are interested in developing UV-protective approaches based on a detailed understanding of molecular events that occur after UV exposure, focusing particularly on epidermal melanization and the role of the MC1R in genome maintenance.

  6. Pickering emulsions for skin decontamination.

    Science.gov (United States)

    Salerno, Alicia; Bolzinger, Marie-Alexandrine; Rolland, Pauline; Chevalier, Yves; Josse, Denis; Briançon, Stéphanie

    2016-08-01

    This study aimed at developing innovative systems for skin decontamination. Pickering emulsions, i.e. solid-stabilized emulsions, containing silica (S-PE) or Fuller's earth (FE-PE) were formulated. Their efficiency for skin decontamination was evaluated, in vitro, 45min after an exposure to VX, one of the most highly toxic chemical warfare agents. Pickering emulsions were compared to FE (FE-W) and silica (S-W) aqueous suspensions. PE containing an oil with a similar hydrophobicity to VX should promote its extraction. All the formulations reduced significantly the amount of VX quantified on and into the skin compared to the control. Wiping the skin surface with a pad already allowed removing more than half of VX. FE-W was the less efficient (85% of VX removed). The other formulations (FE-PE, S-PE and S-W) resulted in more than 90% of the quantity of VX removed. The charge of particles was the most influential factor. The low pH of formulations containing silica favored electrostatic interactions of VX with particles explaining the better elimination from the skin surface. Formulations containing FE had basic pH, and weak interactions with VX did not improve the skin decontamination. However, these low interactions between VX and FE promote the transfer of VX into the oil droplets in the FE-PE. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. [Compression treatment for burned skin].

    Science.gov (United States)

    Jaafar, Fadhel; Lassoued, Mohamed A; Sahnoun, Mahdi; Sfar, Souad; Cheikhrouhou, Morched

    2012-02-01

    The regularity of a compressive knit is defined as its ability to perform its function in a burnt skin. This property is essential to avoid the phenomenon of rejection of the material or toxicity problems But: Make knits biocompatible with high burnet of human skin. We fabric knits of elastic material. To ensure good adhesion to the skin, we made elastic material, typically a tight loop knitted. The Length of yarn absorbed by stitch and the raw matter are changed with each sample. The physical properties of each sample are measured and compared. Surface modifications are made to these samples by impregnation of microcapsules based on jojoba oil. Knits are compressif, elastic in all directions, light, thin, comfortable, and washable for hygiene issues. In addition, the washing can find their compressive properties. The Jojoba Oil microcapsules hydrated the human burnet skin. This moisturizer is used to the firmness of the wound and it gives flexibility to the skin. Compressive Knits are biocompatible with burnet skin. The mixture of natural and synthetic fibers is irreplaceable in terms comfort and regularity.

  8. Raman spectroscopy of skin neoplasms

    Science.gov (United States)

    Moryatov, A. A.; Kozlov, S. V.; Kaganov, O. I.; Orlov, A. E.; Zaharov, V. P.; Batrachenko, I. A.; Artemiev, D. N.; Blinov, N. V.

    2017-09-01

    Skin melanoma is spread inhomogeneously worldwide, particularly in Samara region there are high figures of skin neoplasms sick rate as well—18.6%. Research goal: to develop a new method of early non-invasive differential diagnostics of skin neoplasms. Registration of Raman spectrum was implemented in the distance of 3-4 mm, the spectrum registration from pathologically changed zone was subsequently conducted, then from healthy skin zone. The test time for 1 patient was no longer than 3-5 min. In a range of experiments ex vivo there were the following results: melanoma—24, basal cell cancer—25, squamosus cell sarcinoma—7, nevus pigmentosis—9, other malignant neoplasms—6; in vivo: melanoma—9, basal cell cancer—8, nevus pigmentosis—2, other benign neoplasms—2. The first results of the research dedicated to studying permissive opportunities of Raman spectroscopy, with successive two-phase analysis of received parameters display high efficiency of method of differential diagnostic for skin melanoma and other malignant neoplasms, pigment and benign skin neoplasms. Safety and rapidity of the research reveal a high potential of the technique.

  9. Occupational skin cancer: Systematic review

    Directory of Open Access Journals (Sweden)

    Jéssica Suellen Sena

    2016-06-01

    Full Text Available SUMMARY Objective: To analyze the epidemiological profile, risk factors in the workplace environment and prevention methods for professionals at risk of skin cancer. Method: A systematic review of articles on occupational skin cancer, published in the Lilacs, Scielo, Medline and Cochrane Library from January 1st, 2008, to December 31st, 2013, was performed. The search included the following terms: “neoplasias cutâneas” (DeCS, “exposição ocupacional” (DeCS, “epidemiologia” (DeCS as well as the keyword “prevenção”, and their equivalents in English. Results: After analyzing the titles and summaries of articles, the search strategy resulted in 83 references, of which 22 articles met the eligibility criteria. Discussion: We found that sun exposure is the main occupational risk factor for skin cancer, causing outdoor workers to be the most vulnerable to developing occupational skin cancer. Professionals with low levels of education and European descent are at increased risk of developing this cancer. Conclusion: Outdoor workers are more vulnerable to developing occupational skin cancer, estimating that professionals with low level of education and European descent are at increased risk of developing this cancer. Therefore, companies need to invest more in the health of workers by providing protective equipment and thus preventing occupational skin cancer.

  10. Radiation sterilization of skin allograft

    Energy Technology Data Exchange (ETDEWEB)

    Kairiyama, E. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza, Presbitero Juan Gonzalez y Aragon No. 15, (B1802AYA) Ezeiza, Buenos Aires (Argentina)], E-mail: kairiyam@cae.cnea.gov.ar; Horak, C.; Spinosa, M.; Pachado, J. [Comision Nacional de Energia Atomica, Centro Atomico Ezeiza, Presbitero Juan Gonzalez y Aragon No. 15, (B1802AYA) Ezeiza, Buenos Aires (Argentina); Schwint, O. [J.P. Garrahan Hospital, Buenos Aires (Argentina)

    2009-07-15

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10{sup -6}. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm{sup 2}. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  11. Radiation sterilization of skin allograft

    Science.gov (United States)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-07-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  12. [Skin cancer incidence in Zacatecas].

    Science.gov (United States)

    Pinedo-Vega, José Luis; Castañeda-López, Rosalba; Dávila-Rangel, J Ignacio; Mireles-García, Fernando; Ríos-Martínez, Carlos; López-Saucedo, Adrián

    2014-01-01

    Skin cancer is the most frequent cancer related to ultraviolet radiation. The aim was to estimate the incidence of skin cancer type, melanoma and non-melanoma in Zacatecas, Mexico. An epidemiological study was carried out during the period from 2008 to 2012. The data were obtained from the Instituto Mexicano del Seguro Social (IMSS), Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), Secretaría de Salud de Zacatecas (SSZ) and a private source, the Centro Médico Alameda. The incidence and the global prevalence were estimated. We studied 958 skin cancer cases, histopathologically confirmed. The cases were distributed as: 63.6 % basal cell carcinomas, 25.8 % squamous cell carcinomas, and 10.6 % melanoma. Significantly higher proportions were observed in women in the basal cell carcinomas (60.4 %) and squamous cell carcinomas (53.4 %). However, in the case of melanoma, the major proportion was observed in men (55.9 %). The more frequent skin cancer location was the face and for basal cell carcinoma was the nose (53 %); for squamous cell carcinomas were the lips (36 %), and for melanoma it was also the nose (40 %). The skin cancer incidence was estimated in 20 cases for each 100 000 inhabitants. Linear regression analysis showed that the skin cancer is increasing at an annual rate of 10.5 %. The anatomical location indicates that solar UV radiation is a risk factor, since the face is the zone with major exposure to solar radiation.

  13. 19 CFR 12.63 - Seal-skin or sea-otter-skin waste.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Seal-skin or sea-otter-skin waste. 12.63 Section... OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Fur-Seal Or Sea-Otter Skins § 12.63 Seal-skin or sea-otter-skin waste. Seal-skin or sea-otter-skin waste composed of small pieces not large enough to be...

  14. Novel living skin replacement biotherapy approach for wounded skin tissues.

    Science.gov (United States)

    LaFrance, M L; Armstrong, D W

    1999-04-01

    A novel living skin replacement (LSR) biotherapy concept, addressing the challenging problems related to tissue regeneration and wound healing, is presented for the treatment of skin burns, traumatic injuries and ulcerations. LSR combines elements of cell therapy along with those of tissue engineering to allow for the regeneration of wounded skin. It takes advantage of biodegradable microspheres onto which donor skin epidermal and dermal cells can be attached and expanded in vitro for subsequent direct application down to the deepest recesses of the wound bed. The key element of the biotherapy is the ability of the skin cells to migrate freely from the microspheres into the wound for regeneration of the tissues. The large surface to volume ratio of the microspheres allows for the delivery of appropriate cell numbers while minimizing the amount of biomaterial to be resorbed. This novel approach presents a number of advantages over existing therapies including facilitated cell manipulations, ease of storage and transportation, rapid clinical intervention due to the elimination of any surgical suturing or stapling, and a more natural three-dimensional tissue remodeling and anatomical compliance. Preliminary in vitro and in vivo evidence of the LSR functionality and its potential benefits is presented.

  15. Metallothionein 3 expression in normal skin and malignant skin lesions.

    Science.gov (United States)

    Pula, Bartosz; Tazbierski, Tadeusz; Zamirska, Aleksandra; Werynska, Bozena; Bieniek, Andrzej; Szepietowski, Jacek; Rys, Janusz; Dziegiel, Piotr; Podhorska-Okolow, Marzena

    2015-01-01

    Metallothionein-3 (MT-3) has been shown to be expressed in several malignancies and to have an impact on patients' survival in breast and urinary bladder cancer cases. However, its expression has not been determined in normal skin or in its malignant lesions. MT-3 expression was studied using immunohistochemistry in 17 cases of normal skin, 18 of actinic keratosis (AK), 39 of squamous cell carcinoma (SCC), and 23 of basal cell carcinoma (BCC). Low MT-3 expression was observed in normal skin epidermis with faint or no expression in the epidermis basal layer. Significantly higher MT-3 expression was noted in AK (P=0.007) and SCC (P<0.0001), as compared with normal skin epidermis. BCC cases were characterized by the lowest MT-3 expression of all the examined groups, which was significantly lower in comparison to normal skin epidermis, AK, and SCC (P=0.009;P<0.0001 and P<0.0001, respectively). In conclusion, MT-3 may be involved in the development of SCC.

  16. Skin interaction with absorbent hygiene products.

    Science.gov (United States)

    Runeman, Bo

    2008-01-01

    Skin problems due to the use of absorbent hygiene products, such as diapers, incontinence pads, and feminine sanitary articles, are mostly due to climate or chafing discomfort. If these conditions are allowed to prevail, these may develop into an irritant contact dermatitis and eventually superficial skin infections. Skin humidity and aging skin are among the most significant predisposing and aggravating factors for dermatitis development. Improved product design features are believed to explain the decline in observed diaper dermatitis among infants. Where adult incontinence-related skin problems are concerned, it is very important to apply a holistic perspective to understand the influences due to the individual's incontinence level and skin condition, as well as the hygiene and skin care measures provided. Individuals with frail, sensitive skin or with skin diseases may preferably have to use high-quality products, equipped with superabsorbent polymers and water vapor-permeable back sheets, to minimize the risk of skin complications.

  17. Self-reported skin morbidity in Denmark

    DEFF Research Database (Denmark)

    Miller, Iben Marie; Zarchi, Kian; Ellervik, Christina

    2016-01-01

    Skin diseases are thought to be common in the general population. In 2004, a cross-sectional study in Norway, using a validated questionnaire for 18,770 individuals, revealed a high prevalence of skin diseases in the general population. To describe the prevalence of self-reported skin morbidities...... questionnaire. In total, 17.2% self-reported skin complaints. The most prominent self-reported skin complaint was itch with an overall prevalence of 6.5%. The skin morbidity most influenced by age was pimples. There was a uniform pattern showing fewer skin complaints with increasing education. Women reported...... skin morbidities more frequently than men. Participants in employment reported fewer skin morbidities compared to unemployed participants. Skin morbidities in Denmark are common, and the distribution of prevalence estimates in the Danish population parallel those of the Norwegian population, although...

  18. Skin Cancer and UV Protection

    Directory of Open Access Journals (Sweden)

    Tarbuk Anita

    2016-03-01

    Full Text Available The incidence of skin cancer is increasing by epidemic proportions. Basal cell cancer remains the most common skin neoplasm, and simple excision is generally curative. On the other hand, aggressive local growth and metastasis are common features of malignant melanoma, which accounts for 75% of all deaths associated with skin cancer. The primary cause of skin cancer is long exposure to solar ultraviolet radiation (UV-R crossed with the amount of skin pigmentation and family genetics. It is believed that in childhood and adolescence, 80% of UV-R gets absorbed while in the remaining, 20 % gets absorbed later in the lifetime. This suggests that proper and early photoprotection may reduce the risk of subsequent occurrence of skin cancer. Reducing the exposure time to sunlight, using sunscreens and protective textiles are the three ways of UV protection. Most people think that all the clothing will protect them, but it does not provide full sun screening properties. Literature sources claim that only 1/3 of the spring and summer collections tested give off proper UV protection. This is very important during the summer months, when UV index is the highest. Fabric UV protection ability highly depends on large number of factors such as type of fiber, fabric surface, construction, porosity, density, moisture content, type and concentration of dyestuff, fluorescent whitening agents, UV-B protective agents (UV absorbers, as well as nanoparticles, if applied. For all of these reasons, in the present paper, the results of UV protecting ability according to AS/NZS 4399:1996 will be discussed to show that standard clothing materials are not always adequate to prevent effect of UV-R to the human skin; and to suggest the possibilities for its improvement for this purpose enhancing light conversion and scattering. Additionally, the discrepancy in UV protection was investigated in distilled water as well as Adriatic Sea water.

  19. Skin Findings in Williams Syndrome

    Science.gov (United States)

    Kozel, Beth A.; Bayliss, Susan J.; Berk, David R.; Waxler, Jessica L; Knutsen, Russell H.; Danback, Joshua R.; Pober, Barbara R.

    2014-01-01

    Previous examination in a small number of individuals with Williams syndrome (also referred to as Williams-Beuren syndrome) has shown subtly softer skin and reduced deposition of elastin, an elastic matrix protein important in tissue recoil. No quantitative information about skin elasticity in individuals with Williams syndrome is available; nor has there been a complete report of dermatologic findings in this population. To fill this knowledge gap, 94 patients with Williams syndrome aged 7-50 years were recruited as part of the Skin and Vascular Elasticity (WS-SAVE) study. They underwent either a clinical dermatologic assessment by trained dermatologists (2010 WSA family meeting) or measurement of biomechanical properties of the skin with the DermaLab™ suction cup (2012 WSA family meeting). Clinical assessment confirmed that soft skin is common in this population (83%), as is premature graying of the hair (80% of those 20 years or older), while wrinkles (92%) and abnormal scarring (33%) were detected in larger than expected proportions. Biomechanical studies detected statistically significant differences in dP (the pressure required to lift the skin), dT (the time required to raise the skin through a prescribed gradient), VE (viscoelasticity) and E (Young’s modulus) relative to matched controls. The RT (retraction time) also trended longer but was not significant. The biomechanical differences noted in these patients did not correlate with the presence of vascular defects also attributable to elastin insufficiency (vascular stiffness, hypertension, and arterial stenosis) suggesting the presence of tissue specific modifiers that modulate the impact of elastin insufficiency in each tissue. PMID:24920525

  20. Skin simulators for dermatological procedures.

    Science.gov (United States)

    Wang, Xiaojie; Albahrani, Yasser; Pan, Michael; Levitt, Jacob

    2015-11-18

    A variety of skin simulators are available on which to practice procedures; however, choice of a suboptimal substitute compromises realism and productive practice. Skin simulators for basic dermatological procedures are reviewed. The authors' anecdotal experience with various skin simulators for different procedures is shared. The following simulators are suggested:  an unripe banana for elliptical excision, pork belly for undermining, pork belly for simple interrupted and buried suture, capped needle on a human shoulder for intramuscular injection, ripe tomato or hotdog with skin for intradermal injection, eggplant for shave biopsy, pork belly for punch biopsy, plastic tape over a dark surface for cryosurgery, and beef liver for electrosurgery.  Flaps are best practiced with foam sandwiched between foam tape or artificial anatomical models created specifically for this purpose. The utility of one simulator over another was not compared in a controlled study. Efficient, realistic skin simulators are readily available for practice, which should enhance the safety of the practitioner and improve outcomes of novices.

  1. Biological Rhythms in the Skin.

    Science.gov (United States)

    Matsui, Mary S; Pelle, Edward; Dong, Kelly; Pernodet, Nadine

    2016-05-24

    Circadian rhythms, ≈24 h oscillations in behavior and physiology, are reflected in all cells of the body and function to optimize cellular functions and meet environmental challenges associated with the solar day. This multi-oscillatory network is entrained by the master pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus, which directs an organism's rhythmic expression of physiological functions and behavior via a hierarchical system. This system has been highly conserved throughout evolution and uses transcriptional-translational autoregulatory loops. This master clock, following environmental cues, regulates an organism's sleep pattern, body temperature, cardiac activity and blood pressure, hormone secretion, oxygen consumption and metabolic rate. Mammalian peripheral clocks and clock gene expression have recently been discovered and are present in all nucleated cells in our body. Like other essential organ of the body, the skin also has cycles that are informed by this master regulator. In addition, skin cells have peripheral clocks that can function autonomously. First described in 2000 for skin, this review summarizes some important aspects of a rapidly growing body of research in circadian and ultradian (an oscillation that repeats multiple times during a 24 h period) cutaneous rhythms, including clock mechanisms, functional manifestations, and stimuli that entrain or disrupt normal cycling. Some specific relationships between disrupted clock signaling and consequences to skin health are discussed in more depth in the other invited articles in this IJMS issue on Sleep, Circadian Rhythm and Skin.

  2. Fuzzy description of skin lesions

    Science.gov (United States)

    Laskaris, Nikolaos; Ballerini, Lucia; Fisher, Robert B.; Aldridge, Ben; Rees, Jonathan

    2010-02-01

    We propose a system for describing skin lesions images based on a human perception model. Pigmented skin lesions including melanoma and other types of skin cancer as well as non-malignant lesions are used. Works on classification of skin lesions already exist but they mainly concentrate on melanoma. The novelty of our work is that our system gives to skin lesion images a semantic label in a manner similar to humans. This work consists of two parts: first we capture they way users perceive each lesion, second we train a machine learning system that simulates how people describe images. For the first part, we choose 5 attributes: colour (light to dark), colour uniformity (uniform to non-uniform), symmetry (symmetric to non-symmetric), border (regular to irregular), texture (smooth to rough). Using a web based form we asked people to pick a value of each attribute for each lesion. In the second part, we extract 93 features from each lesions and we trained a machine learning algorithm using such features as input and the values of the human attributes as output. Results are quite promising, especially for the colour related attributes, where our system classifies over 80% of the lesions into the same semantic classes as humans.

  3. Smart skin patterns protect springtails.

    Directory of Open Access Journals (Sweden)

    Ralf Helbig

    Full Text Available Springtails, arthropods who live in soil, in decaying material, and on plants, have adapted to demanding conditions by evolving extremely effective and robust anti-adhesive skin patterns. However, details of these unique properties and their structural basis are still unknown. Here we demonstrate that collembolan skin can resist wetting by many organic liquids and at elevated pressures. We show that the combination of bristles and a comb-like hexagonal or rhombic mesh of interconnected nanoscopic granules distinguish the skin of springtails from anti-adhesive plant surfaces. Furthermore, the negative overhang in the profile of the ridges and granules were revealed to be a highly effective, but as yet neglected, design principle of collembolan skin. We suggest an explanation for the non-wetting characteristics of surfaces consisting of such profiles irrespective of the chemical composition. Many valuable opportunities arise from the translation of the described comb-like patterns and overhanging profiles of collembolan skin into man-made surfaces that combine stability against wear and friction with superior non-wetting and anti-adhesive characteristics.

  4. Hyperspectral imaging of bruised skin

    Science.gov (United States)

    Randeberg, Lise L.; Baarstad, Ivar; Løke, Trond; Kaspersen, Peter; Svaasand, Lars O.

    2006-02-01

    Bruises can be important evidence in legal medicine, for example in cases of child abuse. Optical techniques can be used to discriminate and quantify the chromophores present in bruised skin, and thereby aid dating of an injury. However, spectroscopic techniques provide only average chromophore concentrations for the sampled volume, and contain little information about the spatial chromophore distribution in the bruise. Hyperspectral imaging combines the power of imaging and spectroscopy, and can provide both spectroscopic and spatial information. In this study a hyperspectral imaging system developed by Norsk Elektro Optikk AS was used to measure the temporal development of bruised skin in a human volunteer. The bruises were inflicted by paintball bullets. The wavelength ranges used were 400 - 1000 nm (VNIR) and 900 - 1700 nm (SWIR), and the spectral sampling intervals were 3.7 and 5 nm, respectively. Preliminary results show good spatial discrimination of the bruised areas compared to normal skin. Development of a white spot can be seen in the central zone of the bruises. This central white zone was found to resemble the shape of the object hitting the skin, and is believed to develop in areas where the impact caused vessel damage. These results show that hyperspectral imaging is a promising technique to evaluate the temporal and spatial development of bruises on human skin.

  5. Tribological evaluation of porcine skin.

    Science.gov (United States)

    Xiao, Huaping; Ariyasinghe, Nethika; He, Xingliang; Liang, Hong

    2014-04-01

    This research studies the effects of external parameters on the friction of porcine skin. A tribometer was used to evaluate the frictional behavior of the same. The effects of DI water and body oil on porcine skin against steel and glass balls were evaluated in terms of coefficient of friction (COF). The COF dropped rapidly when DI water/body oil was introduced into the sliding system and remained stable when the volume of the liquid exceeded a certain value. The COF increased with increasing sliding speed under dry conditions and decreased in wet. Under an increasing normal force, the COF decreased regardless of the presence of liquid. The ratio of the real contact area to the nominal contact area of the skin with the steel/glass ball was found to increase with a power law as the applied force was increased. These results reveal basic tribological properties of the skin in contact with a hard slider. These properties could be used as reference for the design and development of artificial skin in prosthetic applications. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Skin PAMPA: Application in practice

    Directory of Open Access Journals (Sweden)

    Bálint Sinkó

    2015-01-01

    Full Text Available Transdermal drug delivery has been growing extensively in the past decades, therefore new, reliable and cost-effective in vitro models were demanded to support the research and development on this field. Model membrane of PAMPA mimicking skin penetration was first described in 2006, but the need for more bio-mimetic system has been arisen by new industrial tendencies and a bio-relevant system was published in 2012. Since its first publication Skin PAMPA has already been applied by several universities and industrial groups successfully and the first articles, podium and poster presentations have been appeared. The original Skin PAMPA model has been further developed in order to extend its application for formulations. Examples of liquid or semi-solid formulation projects and transdermal patch studies are available beside standard solution applications. The present review demonstrates the different approaches needed for various type of samples, provides examples of applications and practical conclusions for further improvement.

  7. Warfarin-Induced Skin Necrosis

    Science.gov (United States)

    Papanas, Nikolaos; Karadimas, Efthimios; Polychronidis, Alexandros

    2014-01-01

    Warfarin-induced skin necrosis is an infrequent complication occurring in individuals under warfarin treatment who have a thrombophilic history or after administration of large loading doses of warfarin particularly without simultaneous initial use of heparin. A 62-year-old lady developed skin necrosis 4 days after initiating warfarin therapy of 5 mg daily without initial co-administration of heparin. The patient had a normal clotting profile. Skin necrosis progressed to eschar formation after cessation of warfarin and heparinization stopped expanding. Warfarin was reintroduced at 2 mg daily, initially together with low molecular weight heparin. Autolytic debridement of the necrotic tissue was followed by healing of the cutaneous deficit by secondary intention. Prompt diagnosis and discontinuation of warfarin are crucial for the prognosis. PMID:24648693

  8. Ectodermal Dysplasia Skin Fragility Syndrome

    Directory of Open Access Journals (Sweden)

    Ayça Alan Atalay

    2014-06-01

    Full Text Available Ectodermal dysplasia-skin fragility syndrome (EDSFS is a rare autosomal recessive genodermatosis first described in 1997 by Mc Grath. EDSFS results from loss of function mutations in plakophilin-1 (PKP1. PKP1 is a structural component of desmosomes, cellcell adhesion complexes. It is also found as a nuclear protein in several cell types that are lack of desmosomes. In skin, however, PKP1 expression is confined mainly to suprabasal keratinocytes and the outer root sheath of hair follicules. Loss of function mutation in PKP1 leads to extensive skin fragility, bullae and erosions following minor trauma, focal keratoderma with painful fissures, alopecia, and nail dystrophy. In some patients hypohidrosis may also be seen. EDSFS is now considered as a specific suprabasal form of epidermolysis bullosa simplex. In this report we describe a 20 year old EDSFS case.

  9. Aircraft Skin Restoration and Evaluation

    Science.gov (United States)

    Yandouzi, M.; Gaydos, S.; Guo, D.; Ghelichi, R.; Jodoin, B.

    2014-12-01

    The recent development of the cold spray technology has made possible the deposition of low porosity and oxide-free coatings with good adhesion and with almost no change in the microstructure of the coated parts. This focuses on the use of low-pressure cold spray process to repair damaged Al-based aircraft skin, aiming at obtaining dense coatings with strong adhesion to the Al2024-T3 alloy. In order to prove the feasibility of using of the cold spray process as a repair process for aircraft skin, series of characterisation/tests including microstructures, microhardness, adhesion strength, three-point bending, surface finish, fatigue test, and corrosion resistance were performed. The obtained results revealed that the low-pressure cold spray process is a suitable for the repair of aircraft skin.

  10. UV clothing and skin cancer.

    Science.gov (United States)

    Tarbuk, Anita; Grancarić, Ana Marija; Situm, Mirna; Martinis, Mladen

    2010-04-01

    Skin cancer incidence in Croatia is steadily increasing in spite of public and governmental permanently measurements. It is clear that will soon become a major public health problem. The primary cause of skin cancer is believed to be a long exposure to solar ultraviolet (UV) radiation. The future designers of UV protective materials should be able to block totally the ultraviolet radiation. The aim of this paper is to present results of measurements concerning UV protecting ability of garments and sun-screening textiles using transmission spectrophotometer Cary 50 Solarscreen (Varian) according to AS/NZS 4399:1996; to show that standard clothing materials are not always adequate to prevent effect of UV radiation to the human skin; and to suggest the possibilities for its improvement for this purpose.

  11. A survey of skin disease and skin-related issues in Arab Americans.

    Science.gov (United States)

    El-Essawi, Dina; Musial, Joseph L; Hammad, Adnan; Lim, Henry W

    2007-06-01

    There is a paucity of knowledge relating to dermatologic conditions in Arab Americans. To assess common skin diseases and concerns and to evaluate access to dermatologic care and perception of skin in Arab Americans. Arab Americans from 3 Southeast Michigan locations (community health center [n = 207], mosque [n = 95], and church [n = 99]) completed a survey questionnaire. The most common self-reported skin conditions were acne, eczema/dermatitis, warts, fungal skin infections, and melasma. The most pressing skin concerns were uneven skin tone, skin discoloration, dry skin, acne, and facial hair. Significant associations exist between socioeconomic status and having seen a dermatologist. Attitudes surrounding skin perception were related to the number of years of residence in the United States. The skin condition data were gathered from a self-reported survey. Skin conditions and other related issues that affect Arab Americans are similar to those which affect other skin-of-color populations.

  12. Preparation of Artificial Skin that Mimics Human Skin Surface and Mechanical Properties.

    Science.gov (United States)

    Shimizu, Rana; Nonomura, Yoshimune

    2017-12-14

    We have developed an artificial skin that mimics the morphological and mechanical properties of human skin. The artificial skin comprises a polyurethane block possessing a microscopically rough surface. We evaluated the tactile sensations when skin-care cream was applied to the artificial skin. Many subjects perceived smooth, moist, and soft feels during the application process. Cluster analysis showed that these characteristic tactile feels are similar to those when skin-care cream is applied to real human skin. Contact angle analysis showed that an oil droplet spread smoothly on the artificial skin surface, which occurred because there were many grooves several hundred micrometers in width on the skin surface. In addition, when the skin-care cream was applied, the change in frictional force during the dynamic friction process increased. These wetting and frictional properties are important factors controlling the similarity of artificial skin to real human skin.

  13. Clinical utility of skin karyotype

    Directory of Open Access Journals (Sweden)

    Luiza E. Dorfman

    2015-08-01

    Full Text Available ABSTRACTWe report the case of a patient with Patau syndrome, diagnosed by skin karyotype, emphasizing the applications and importance of this test. The pregnancy morphology ultrasound showed face defects and of central nervous system and heart chambers asymmetry. In the postnatal evaluation it was identified microcephaly, single central nostril, and other malformations. We performed skin karyotype that resulted in full trisomy 13. Our report highlights the possibility of performing karyotype examination in cases when it is no longer possible to obtain a blood sample, thus providing the correct diagnosis and genetic counseling for the family.

  14. Warfarin-induced skin necrosis.

    Science.gov (United States)

    Gelwix, T J; Beeson, M S

    1998-09-01

    Skin necrosis is an uncommon complication of warfarin (Coumadin; Dupont Pharma, Wilmington, DE) therapy. The presentation may mimic other disorders. This article reports a case of a 72-year-old woman who presented to the emergency department complaining of swelling and ecchymosis to her left breast and right foot. The patient had been hospitalized for coronary artery bypass grafting, and had been discharged from the hospital earlier that day. This article reviews the pathophysiology and clinical features of warfarin-induced skin necrosis.

  15. Skin scoring in systemic sclerosis

    DEFF Research Database (Denmark)

    Zachariae, Hugh; Bjerring, Peter; Halkier-Sørensen, Lars

    1994-01-01

    Forty-one patients with systemic sclerosis were investigated with a new and simple skin score method measuring the degree of thickening and pliability in seven regions together with area involvement in each region. The highest values were, as expected, found in diffuse cutaneous systemic sclerosis...... (type III SS) and the lowest in limited cutaneous systemic sclerosis (type I SS) with no lesions extending above wrists and ancles. A positive correlation was found to the aminoterminal propeptide of type III procollagen, a serological marker for synthesis of type III collagen. The skin score...

  16. Skin tightening-does it really exist?

    Science.gov (United States)

    Boen, Monica; Vanaman Wilson, Monique J; Fabi, Sabrina

    2017-12-01

    Skin tightening is one of the cornerstones of skin rejuvenation and is defined as the improvement of skin laxity and crepiness of the skin. There are several energy-based devices that can produce significant skin tightening without surgery, both on and off the face. The mechanisms of skin tightening involve collagen denaturation resulting in collagen shrinkage and tissue tightening, and the wound healing response that generates new collagen and elastin. These hypothesized mechanisms of skin contraction leading to clinical skin tightening have been derived from histological, immunohistochemical, and electron microscope analysis, as well as in vitro and in vivo experiments. This review is aimed at evaluating and analyzing the literature on the proposed mechanisms for skin tightening by minimally invasive energy-based technologies. ©2017 Frontline Medical Communications.

  17. Scar treatment variations by skin type.

    Science.gov (United States)

    Visscher, Marty O; Bailey, J Kevin; Hom, David B

    2014-08-01

    Patients and clinicians use skin color attributes such as color uniformity, color distribution, and texture to infer physiologic health status. Normalization of skin color, surface texture, and height are important treatment goals in the treatment of scars. Skin color, structure, and response to trauma, vary with ethnicity. The incidence of hypertrophic and keloid scar formation is influenced by these inherent skin attributes. Skin type influences the response to various modalities including laser therapy and surgical intervention, and skin differences must be considered in treatment planning to achieve optimal results. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. A disappearing neonatal skin lesion.

    LENUS (Irish Health Repository)

    Hawkes, Colin Patrick

    2012-01-31

    A preterm baby girl was noted at birth to have a firm, raised, non-tender skin lesion located over her right hip. She developed three similar smaller lesions on her ear, buttock and right knee. All lesions had resolved by 2 months of age.

  19. Skin Autofluorescence and Glycemic Variability

    NARCIS (Netherlands)

    Noordzij, M. J.; Lefrandt, J. D.; Graaff, R.; Smit, A. J.

    Background: Accumulation of advanced glycation end products (AGEs) is accelerated during glycemic and oxidative stress and is an important predictor of complications in diabetes mellitus (DM). Study Design: Here we both review and present original data on the relationship between skin

  20. Skin diseases of the vulva

    DEFF Research Database (Denmark)

    Sand, Freja Lærke; Thomsen, Simon Francis

    2017-01-01

    A multitude of infectious diseases of viral (genital herpes, herpes zoster, genital warts and molluscum contagiosum), bacterial (syphilis, chancroid, lymphogranuloma venereum, donovanosis, erysipelas, cellulitis and necrotising fasciitis, folliculitis, impetigo, bartholin gland abscess, trichomyc......, trichomycosis and erythrasma), fungal (candidiasis and dermatophytosis) and parasitic (pediculosis pubis) origin may affect the vulvar area. Herein, we review the infections and their skin manifestations in the vulvar area....

  1. Skin Cancers of the Feet

    Science.gov (United States)

    ... and/or a diameter greater than 6 mm. Melanomas may resemble benign moles, blood blisters, ingrown nails, plantar warts, ulcers ... for patients for the early detection of both benign and malignant skin tumors. Learn the ABCDs of melanoma. If you notice a mole, bump, or patch ...

  2. Cutaneous flavobacteriosis - polymorphous skin granulomas ...

    African Journals Online (AJOL)

    A case of multiple eruptive skin granulomas caused by Flavobacterium capsulatum is described. The organism was resistant or poorly sensitive to all antibiotics except carbenicillin. Cure was brought about by using maximal doses of this drug. The source of the infection could not be proved, but it dated from an orthopaedic ...

  3. Cleansing Formulations That Respect Skin Barrier Integrity

    Directory of Open Access Journals (Sweden)

    Russel M. Walters

    2012-01-01

    Full Text Available Surfactants in skin cleansers interact with the skin in several manners. In addition to the desired benefit of providing skin hygiene, surfactants also extract skin components during cleansing and remain in the stratum corneum (SC after rinsing. These side effects disrupt SC structure and degrade its barrier properties. Recent applications of vibrational spectroscopy and two-photon microscopy in skin research have provided molecular-level information to facilitate our understanding of the interaction between skin and surfactant. In the arena of commercial skin cleansers, technologies have been developed to produce cleansers that both cleanse and respect skin barrier. The main approach is to minimize surfactant interaction with skin through altering its solution properties. Recently, hydrophobically modified polymers (HMPs have been introduced to create skin compatible cleansing systems. At the presence of HMP, surfactants assemble into larger, more stable structures. These structures are less likely to penetrate the skin, thereby resulting in less aggressive cleansers and the integrity of the skin barrier is maintained. In this paper, we reviewed our recent findings on surfactant and SC interactions at molecular level and provided an overview of the HM technology for developing cleansers that respect skin barrier.

  4. Enhanced chlorhexidine skin penetration with eucalyptus oil

    Directory of Open Access Journals (Sweden)

    Worthington Tony

    2010-09-01

    Full Text Available Abstract Background Chlorhexidine digluconate (CHG is a widely used skin antiseptic, however it poorly penetrates the skin, limiting its efficacy against microorganisms residing beneath the surface layers of skin. The aim of the current study was to improve the delivery of chlorhexidine digluconate (CHG when used as a skin antiseptic. Method Chlorhexidine was applied to the surface of donor skin and its penetration and retention under different conditions was evaluated. Skin penetration studies were performed on full-thickness donor human skin using a Franz diffusion cell system. Skin was exposed to 2% (w/v CHG in various concentrations of eucalyptus oil (EO and 70% (v/v isopropyl alcohol (IPA. The concentration of CHG (μg/mg of skin was determined to a skin depth of 1500 μm by high performance liquid chromatography (HPLC. Results The 2% (w/v CHG penetration into the lower layers of skin was significantly enhanced in the presence of EO. Ten percent (v/v EO in combination with 2% (w/v CHG in 70% (v/v IPA significantly increased the amount of CHG which penetrated into the skin within 2 min. Conclusion The delivery of CHG into the epidermis and dermis can be enhanced by combination with EO, which in turn may improve biocide contact with additional microorganisms present in the skin, thereby enhancing antisepsis.

  5. Oxidation events and skin aging.

    Science.gov (United States)

    Kammeyer, A; Luiten, R M

    2015-05-01

    The rate of skin aging, or that of tissue in general, is determined by a variable predominance of tissue degeneration over tissue regeneration. This review discusses the role of oxidative events of tissue degeneration and aging in general, and for the skin in particular. The mechanisms involved in intrinsic and extrinsic (photo-) aging are described. Since photoaging is recognized as an important extrinsic aging factor, we put special emphasize on the effects of UV exposure on aging, and its variable influence according to global location and skin type. We here summarise direct photochemical effects of UV on DNA, RNA, proteins and vitamin D, the factors contributing to UV-induced immunosuppression, which may delay aging, the nature and origin of reactive oxygen species (ROS) and reactive nitrogen species (RNS) as indirect contributors for aging, and the consequences of oxidative events for extracellular matrix (ECM) degradation, such as that of collagen. We conclude that conflicting data on studies investigating the validity of the free radical damage theory of aging may reflect variations in the level of ROS induction which is difficult to quantify in vivo, and the lack of targeting of experimental ROS to the relevant cellular compartment. Also mitohormesis, an adaptive response, may arise in vivo to moderate ROS levels, further complicating interpretation of in vivo results. We here describes how skin aging is mediated both directly and indirectly by oxidative degeneration.This review indicates that skin aging events are initiated and often propagated by oxidation events, despite recently recognized adaptive responses to oxidative stress. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. What Causes Our Skin to Age?

    Science.gov (United States)

    ... benefits Become a member DermCare Team Professionalism and ethics My account Member directory Publications JAAD JAAD Case ... SkinPAC State societies Scope of practice Truth in advertising Public and patients SPOT Skin Cancer™ Community programs & ...

  7. About Skin: Your Body's Largest Organ

    Science.gov (United States)

    ... benefits Become a member DermCare Team Professionalism and ethics My account Member directory Publications JAAD JAAD Case ... SkinPAC State societies Scope of practice Truth in advertising Public and patients SPOT Skin Cancer™ Community programs & ...

  8. Forensic identification using skin bacterial communities

    National Research Council Canada - National Science Library

    Noah Fierer; Christian L. Lauber; Nick Zhou; Daniel McDonald; Elizabeth K. Costello; Rob Knight; Jeffrey I. Gordon

    2010-01-01

    ... of bacterial communities. Given that skin bacterial communities are personalized, we hypothesized that we could use the residual skin bacteria left on objects for forensic identification, matching the bacteria on the object...

  9. Ceftaroline in complicated skin and skin-structure infections

    Directory of Open Access Journals (Sweden)

    Hernandez PO

    2012-01-01

    Full Text Available Paul O Hernandez1, Sergio Lema2, Stephen K Tyring3, Natalia Mendoza2,41University of Texas School of Medicine at San Antonio, San Antonio, TX, 2Woodhull Medical and Mental Health Center, Brooklyn, NY, 3Department of Dermatology, University of Texas Health Science Center at Houston, Houston, TX, USA; 4Department of Dermatology, El Bosque University, Bogotá, ColombiaAbstract: Ceftaroline is an advanced-generation cephalosporin antibiotic recently approved by the US Food and Drug Administration for the treatment of complicated skin and skin-structure infections (cSSSIs. This intravenous broad-spectrum antibiotic exerts potent bactericidal activity by inhibiting bacterial cell wall synthesis. A high affinity for the penicillin-binding protein 2a (PBP2a of methicillin-resistant Staphylococcus aureus (MRSA makes the drug especially beneficial to patients with MRSA cSSSIs. Ceftaroline has proved in multiple well-conducted clinical trials to have an excellent safety and efficacy profile. In adjusted doses it is also recommended for patients with renal or hepatic impairment. Furthermore, the clinical effectiveness and high cure rate demonstrated by ceftaroline in cSSSIs, including those caused by MRSA and other multidrug-resistant strains, warrants its consideration as a first-line treatment option for cSSSIs. This article reviews ceftaroline and its pharmacology, efficacy, and safety data to further elucidate its role in the treatment of cSSSIs.Keywords: ceftaroline, cephalosporin, complicated skin and skin-structure infections, cSSSIs, MRSA, Teflaro®

  10. Occupational skin cancer may be underreported

    DEFF Research Database (Denmark)

    Carøe, Tanja Korfitsen; Ebbehøj, Niels Erik; Wulf, Hans Christian

    2013-01-01

    Skin cancer may, in some cases, be caused by occupational exposures. The aim of this study was to investigate the prevalence of and exposures leading to occupationally induced skin cancers in Denmark during a ten-year period.......Skin cancer may, in some cases, be caused by occupational exposures. The aim of this study was to investigate the prevalence of and exposures leading to occupationally induced skin cancers in Denmark during a ten-year period....

  11. Nanocarriers for skin delivery of cosmetic antioxidants

    OpenAIRE

    Lucia Montenegro

    2014-01-01

    The demand of natural skin care products is steadily growing since consumers perceive them as safe. Currently, cosmetic manufacturers are focusing their efforts on developing innovative natural products to address skin-aging signs, thus meeting consumers’ needs of healthy appearance and well-being. To prevent or treat skin aging, topical supplementation with antioxidant is regarded as one of the most promising strategies. However, most antioxidants presently used in skin care formulations sho...

  12. Skin colour and bilirubin in neonates.

    OpenAIRE

    Knudsen, A.; Brodersen, R

    1989-01-01

    The correlation between the yellow colour of the skin and serum bilirubin concentration, reserve albumin concentration, and pH was investigated in 76 icteric neonates. Significant linear correlation existed between yellow colour of the skin and serum bilirubin concentration, reciprocal of the reserve albumin concentration, and the squared hydrogen ion concentration. Furthermore, the basic yellowness of the skin at birth correlated linearily with the yellow colour of the skin measured when the...

  13. The Microbiota of the Human Skin.

    Science.gov (United States)

    Egert, Markus; Simmering, Rainer

    2016-01-01

    The aim of this chapter is to sum up important progress in the field of human skin microbiota research that was achieved over the last years.The human skin is one of the largest and most versatile organs of the human body. Owing to its function as a protective interface between the largely sterile interior of the human body and the highly microbially contaminated outer environment, it is densely colonized with a diverse and active microbiota. This skin microbiota is of high importance for human health and well-being. It is implicated in several severe skin diseases and plays a major role in wound infections. Many less severe, but negatively perceived cosmetic skin phenomena are linked with skin microbes, too. In addition, skin microorganisms, in particular on the human hands, are crucial for the field of hygiene research. Notably, apart from being only a potential source of disease and contamination, the skin microbiota also contributes to the protective functions of the human skin in many ways. Finally, the analysis of structure and function of the human skin microbiota is interesting from a basic, evolutionary perspective on human microbe interactions.Key questions in the field of skin microbiota research deal with (a) a deeper understanding of the structure (species inventory) and function (physiology) of the healthy human skin microbiota in space and time, (b) the distinction of resident and transient skin microbiota members, (c) the distinction of beneficial skin microorganisms from microorganisms or communities with an adverse or sickening effect on their hosts, (d) factors shaping the skin microbiota and its functional role in health and disease, (e) strategies to manipulate the skin microbiota for therapeutic reasons.

  14. Facial skin care products and cosmetics.

    Science.gov (United States)

    Draelos, Zoe Diana

    2014-01-01

    Facial skin care products and cosmetics can both aid or incite facial dermatoses. Properly selected skin care can create an environment for barrier repair aiding in the re-establishment of a healing biofilm and diminution of facial redness; however, skin care products that aggressively remove intercellular lipids or cause irritation must be eliminated before the red face will resolve. Cosmetics are an additive variable either aiding or challenging facial skin health. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Percutaneous penetration through slightly damaged skin

    DEFF Research Database (Denmark)

    Nielsen, Jesper B

    2005-01-01

    Guidelines for experimental studies of percutaneous penetration prescribe optimal barrier integrity of the skin. The barrier integrity of the skin exposed in occupational or household situations is, however, not always ideal, and skin problems are among the most dominant reasons for absence from ...

  16. Human skin equivalents for atopic dermatitis : investigating the role of filaggrin in the skin barrier

    NARCIS (Netherlands)

    Drongelen, Vincent van

    2014-01-01

    Atopic Dermatitis (AD) is a frequent occurring inflammatory skin disease causing physical discomfort, social embarrassment and stress. This skin disease is characterized by decreased skin barrier function and various other epidermal changes, as well as immunological changes. A decreased skin barrier

  17. Skin-to-skin care in neonatal intensive care units in the Nordic countries

    DEFF Research Database (Denmark)

    Olsson, Emma; Andersen, Lise Randi; Axelin, Anna

    2012-01-01

    To investigate the application of skin-to-skin care (SSC) in the Nordic countries, the existence of guidelines for SSC and the attitudes of neonatal staff towards SSC.......To investigate the application of skin-to-skin care (SSC) in the Nordic countries, the existence of guidelines for SSC and the attitudes of neonatal staff towards SSC....

  18. Anti-oxidant defence mechanism in vitiliginous skin increases with skin type

    NARCIS (Netherlands)

    Briganti, S.; Caron-Schreinemachers, A.-L. D. B.; Picardo, M.; Westerhof, W.

    2012-01-01

    Background Vitiligo skin shows different burning capacity in people with different phototype. In normal skin antioxidant status is correlated to skin phototype, but unexpectedly it appears that there is a gradual decrease in burning susceptibility of depigmented skin of individuals with increasing

  19. Extremely preterm infants tolerate skin-to-skin contact during the first weeks of life

    DEFF Research Database (Denmark)

    Maastrup, Ragnhild; Greisen, Gorm

    2010-01-01

    To determine if clinically stable extremely preterm infants can maintain their temperature during skin-to-skin contact and to screen for other negative effects.......To determine if clinically stable extremely preterm infants can maintain their temperature during skin-to-skin contact and to screen for other negative effects....

  20. High temperature skin friction measurement

    Science.gov (United States)

    Tcheng, Ping; Holmes, Harlan K.; Supplee, Frank H., Jr.

    1989-01-01

    Skin friction measurement in the NASA Langley hypersonic propulsion facility is described. The sensor configuration utilized an existing balance, modified to provide thermal isolation and an increased standoff distance. For test run times of about 20 sec and ambient-air cooling of the test section and balance, the modified balance performed satisfactorily, even when it was subjected to acoustic and structural vibration. The balance is an inertially balanced closed-loop servo system where the current to a moving-coil motor needed to restore or null the output from the position sensor is a measure of the force or skin friction tending to displace the moving element. The accuracy of the sensor is directly affected by the position sensor in the feedback loop, in this case a linear-variable differential transformer which has proven to be influenced by temperature gradients.