Sample records for bufo arenarum induced
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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.
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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
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Mechanisms underlying the organizer formation in Bufo arenarum embryos.
Manes, M E; Nieto, O L
1989-06-01
In the early gastrula of Bufo arenarum the prospective mesoderm was previously identified as a marginal belt of grey cells. To analyze their differentiation capacity explants of these cells were cultured within ectodermal vesicles, in isolation and in combination with vegetal components. When cultured in isolation, dorsal and ventral fragments from the deep marginal zone behaved differently. Whilst ventral explants produced blood cells, dorsal explants failed to differentiate, remaining as masses of yolk-laden cells. On the other hand, both cultures were drastically modified when associated with superficial cells from the blastoporal zone, which caused the following effects: a) Promotion of differentiation in dorsal marginal explants, able now to produce notochordal and somitic structures, in addition to mesenchymatic cells. b) Promotion of dorsalization in ventral marginal explants, which changed their expected destiny developing axial components, similar to those furnished by "activated" dorso marginal explants. On the contrary, combined cultures of animal and vegetal pieces were unable to generate mesodermal structures. These studies suggest that the axial mesoderm, identified as the "organizer", develops from a marginal substrate of genuine mesodermal cells through a dorsalizing inductive stimulus originated in superficial periblastoporal cells.
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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.
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The Effect of UV-B Radiation on Bufo arenarum Embryos Survival and Superoxide Dismutase Activity
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
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International Nuclear Information System (INIS)
Bernabò, Ilaria; Bonacci, Antonella; Coscarelli, Francesca; Tripepi, Manuela; Brunelli, Elvira
2013-01-01
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
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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
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Involvement of PLA2, COX and LOX in Rhinella arenarum oocyte maturation.
Ortiz, Maria Eugenia; Bühler, Marta Inés; Zelarayán, Liliana Isabel
2014-11-01
In Rhinella arenarum, progesterone is the physiological nuclear maturation inducer that interacts with the oocyte surface and starts a cascade of events that leads to germinal vesicle breakdown (GVBD). Polyunsaturated fatty acids and their metabolites produced through cyclooxygenase (COX) and lipoxygenase (LOX) pathways play an important role in reproductive processes. In amphibians, to date, the role of arachidonic acid (AA) metabolites in progesterone (P4)-induced oocyte maturation has not been clarified. In this work we studied the participation of three enzymes involved in AA metabolism - phospholipase A2 (PLA2), COX and LOX in Rhinella arenarum oocyte maturation. PLA2 activation induced maturation in Rhinella arenarum oocytes in a dose-dependent manner. Oocytes when treated with 0.08 μM melittin showed the highest response (78 ± 6% GVBD). In follicles, PLA2 activation did not significantly induce maturation at the assayed doses (12 ± 3% GVBD). PLA2 inhibition with quinacrine prevented melittin-induced GVBD in a dose-dependent manner, however PLA2 inactivation did not affect P4-induced maturation. This finding suggests that PLA2 is not the only phospholipase involved in P4-induced maturation in this species. P4-induced oocyte maturation was inhibited by the COX inhibitors indomethacin and rofecoxib (65 ± 3% and 63 ± 3% GVBD, respectively), although COX activity was never blocked by their addition. Follicles showed a similar response following the addition of these inhibitors. Participation of LOX metabolites in maturation seems to be correlated with seasonal variation in ovarian response to P4. During the February to June period (low P4 response), LOX inhibition by nordihydroguaiaretic acid or lysine clonixinate increased maturation by up to 70%. In contrast, during the July to January period (high P4 response), LOX inhibition had no effect on hormone-induced maturation.
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Goater, C. P.
2017-01-01
Density-dependence in worm establishment, numbers, biomass and larval production were examined in primary infections of 0, 10, 40, 80 and 160 larvae of the lung nematode, Rhabdias bufonis in the common toad, Bufo bufo. The infection procedure established 4 non-overlapping levels of infection which persisted until 6 weeks post-infection (p.i.), after which there was an overall decline up to 12 weeks p.i. Worm numbers had no direct effect on adult worm survival but temporal changes in worm weig...
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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
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International Nuclear Information System (INIS)
Mardirosian, Mariana Noelia; Ceschin, Danilo Guillermo; Lascano, Cecilia Inés; Venturino, Andrés
2017-01-01
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"–"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
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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
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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.
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Lajmanovich, Rafael C; Cabagna-Zenklusen, Mariana C; Attademo, Andrés M; Junges, Celina M; Peltzer, Paola M; Bassó, Agustín; Lorenzatti, Eduardo
2014-07-15
The assessment of micronucleated erythrocytes (ME) in blood represents a widely used method for the detection of chromosomal damage by chemical agents, such as herbicides that may occur as water contaminants. We investigated the changes in some circulating blood-cell parameters of tadpoles of the common toad (Rhinella arenarum) that were exposed during 48 or 96 h to three sub-lethal concentrations (3.75, 7.5, and 15 mg/L) of a commercial formulation of a glufosinate-ammonium (GLA)-based herbicide (Liberty(®), LY(®)) as well as to the corresponding active ingredient GLA. The frequency of ME and other erythrocyte nuclear abnormalities (ENA, i.e., lobed nuclei, binucleates or segmented nuclei, kidney-shaped nuclei, notched nuclei, and picnotic nuclei) were evaluated and compared with positive (cyclophosphamide, CP, 40 mg/L) and negative (de-chlorinated tap water) controls. The results indicate that the exposure of R. arenarum tadpoles to LY(®) induces a concentration-dependent increase in ME frequency. The ENA frequency at 48 h was also significantly higher than that in the negative control group for all the chemicals assayed (CP, LY(®) and GLA) whereas at 96 h, increases in ENA over the negative control group were found only for CP and GLA (7.5 mg/L). Our study demonstrates that the commercial formulation of a GLA-based herbicide induces micronucleus formation in R. arenarum tadpoles, in contrast to the active ingredient. According to these results, the inert ingredients of the commercial formulation played an important role in the production of genotoxic damage in erythrocytes of amphibian tadpoles. Copyright © 2014 Elsevier B.V. All rights reserved.
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VIGNES, J.C.
1998-01-01
Se aportan las primeras observaciones sobre Bufo bufo, que vienen a completar los estudios de alimentación de anuros juveniles realizados en el País Vasco durante el periodo de emergencia. Se analiza el contenido estomacal de 35 individuos (longitud media de 11,54 mm) emergidos de una charca a comienzos de agosto. Todos los jóvenes sapos se alimentan de invertebrados terrestres desde su emergencia, siendo los ácaros de presa más consumida (75,7%), seguida de los coleópteros adultos y los hi...
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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
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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
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Directory of Open Access Journals (Sweden)
VIGNES, J.C.
1998-01-01
Full Text Available Se aportan las primeras observaciones sobre Bufo bufo, que vienen a completar los estudios de alimentación de anuros juveniles realizados en el País Vasco durante el periodo de emergencia. Se analiza el contenido estomacal de 35 individuos (longitud media de 11,54 mm emergidos de una charca a comienzos de agosto. Todos los jóvenes sapos se alimentan de invertebrados terrestres desde su emergencia, siendo los ácaros de presa más consumida (75,7%, seguida de los coleópteros adultos y los himenópteros alados. Aunque las presas fundamentales son las mismas, los regímenes comparados de los metamorfoseados de varias especies de anuros (Rana dalmatina, R. temporaria et Hyla arborea muestran diferencias en la selección trófica.
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A new species of Bufo Laurenti (Anura, Bufonidae from northeastern Brazil
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Maria Nazaré Stevaux
2002-07-01
Full Text Available A new species of bufonid load, Bufo jimi sp. nov., is described from Maracás and Itagibá, State of Bahia, Brazil. This species shows close relationships to B. paracnemis Lutz, 1925 by sharing the presence of tibial glands and the paratoid glands shape. The new species is a member of the Bufo marinus-group, and is characlerized by having well-defined glands in most part of dorsal faceof the forearms, in the extcrn side of the feet and in both sides of cloacal region.
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A DESCRIPTION OF BUFO PARDALIS TADPOLES (ANURA ...
African Journals Online (AJOL)
Tadpoles of Bufo parda/is Hewitt from Kei Road, Cape Province, are described. INTRODUCTION. Although tadpoles of B. pardalis have been included in Van Dijk's (1971) key to the genus Bufa, no adequate description of this taxon has yet been published. Further studies on variability depend upon a complete description ...
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Thyroid anatomy and topography of toad (Bufo marinus ictericus)
International Nuclear Information System (INIS)
Santos, O.R. dos.
1970-01-01
The autoradiographic method is used for the study of the toad's thyroid of Bufo marinus ictericus by 131 I. Histolological proceedings are done. Comparative evaluations with bibliographic informations are presented. (M.A.C.) [pt
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BUFO PARDALIS (ANURA: BUFONIDAE): MATING CALL AND ...
African Journals Online (AJOL)
the calls of one of these species, Bufo pardalis. Hewitt, were not analysed by Tandy & Keith. (1972). Furthennore there is some confusion in the literature regarding the mating call of this species. For these reasons this mating call is here clarified. The mating call of B. pardaiis was first described by Ranger (in Hewitt 1935) as ...
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Trypanosomes of Bufo americanus from northern Michigan.
Werner, J K; Davis, J S; Slaght, K S
1988-10-01
Two hundred one American toads (Bufo americanus) from northern Michigan were examined for blood trypanosomes. Three species, Trypanosoma bufophlebotomi, T. schmidti-like sp. and T. pseudopodia, had prevalences of 27, 16 and 1%, respectively. Cross experimental inoculations showed that T. bufophlebotomi from toads is not the same as T. ranarum found in frogs of the family Ranidae of this region.
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The distribution of Bufo poweri in southern Africa
African Journals Online (AJOL)
1990-03-13
Mar 13, 1990 ... regularis (Frost 1985). ,. Bufo garmani was described from Somalia (Meek 1897), while the morphologically similar B. poweri was described from Kimberley (Hewitt 1935). A long-standing problem has been to determine the status of B. poweri, based on preserved material. These two species are so similar ...
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Directory of Open Access Journals (Sweden)
Cecilia Inés Lascano
2009-07-01
use an amphibian embryonic model (Rhinella arenarum in order to assess the mechanisms by which the OP pesticides azinphos methyl (AM and chlorpyrifos (CP could cause teratogenesis. The embryos were developed in different concentrations of AM or CP until they reached the stage of complete operculum (CO. We analyzed malformations, histology, reduced gluthatione content (GSH and activity of antioxidant enzymes, polyamine content, ornithine decarboxilase (ODC and protein kinase C (PKC activities. Both OP pesticides caused a time- and dose-dependent increase in the number of malformations, reaching 100% teratogenesis in late embryonic development at the highest OP concentrations used. Malformations assessed include exogastrulation, caudal fin curvature, axial shortening, edema, and gill atrophy. Increasing evidence of oxidative stress was observed: GSH dependent enzymes (S- transferase, GST; peroxidase and reductase were early induced in embryos exposed to low concentrations of the OP pesticides, but their activities were inhibited in the stage of CO at high concentrations of OP. These changes were accompanied by a significant decrease in GSH content (62% in embryos exposed to AM. Besides, AM significantly increased (18X ODC activity in the stage of CO, along with putrescine levels (60% of increase but spermidine and spermine levels were significantly decreased (56% and 100%, respectively. The OP pesticide CP caused and early decrease in ODC activity and polyamine levels. The decrease in polyamine levels could be due to an increase in their degradation by polyamine oxidase, contributing to the oxidative stress induced by OP. This, in turn, would cause the decline in GSH levels and the activation of PKC in the embryonic stage of CO (55%, which is involved in the positive feedback of GST and ODC. Finally, the oxidative stress and the decrease in PA levels could be the cause of the observed embryonic alterations.
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Haematological changes in Bufo maculatus treated with sublethal concentrations of Cadmium
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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.
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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 ...
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Reacción de galli mainini para el diagnóstico precoz del embarazo
Angel Mejía, Gilberto
2011-01-01
La reacción de Galli Mainini efectuada en batracios machos parael diagnóstico precoz del embarazo, se deriva del conjunto de trabajos realizados por Houssay y su escuela, quienes desde el año de 1922 venían trabajando en forma intensa e ininterrumpida, sobre anatomía histología y fisiología gonadales, observando las relaciones entre éstas y las gonadotrofinas en diversos batracios. En el año de 1929 hallaron la liberación de los espermatozoides en el testículo del Bufo arenarum Hensel, por la...
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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.
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Seasonal and daily plasma corticosterone rhythms in American toads, Bufo americanus
International Nuclear Information System (INIS)
Pancak, M.K.; Taylor, D.H.
1983-01-01
Concentrations of corticosterone were measured in the plasma of American toads, Bufo americanus, on a seasonal basis using a radioimmunoassay technique. Two populations of toads, maintained under different light conditions, were monitored to observe the effects of photoperiod on the seasonal rhythm of plasma corticosterone. Under a natural photoperiod toads demonstrated a rhythm consisting of a spring peak and a fall peak in corticosterone concentration. Toads maintained under a 12L:12D photoperiod all year round demonstrated a similar rhythm with peaks in the spring and fall. This suggests that an endogenous (circannual) rhythm of corticosterone may be playing an important role in the seasonal change of overt behavior and physiology of Bufo americanus. A daily rhythm of corticosterone was also detected in toads when blood samples were taken every 4 hr. When compared to a previously published circadian rhythm study of locomotor activity, the surge in corticosterone concentration for the day occurred at 1730 just prior to the peak in locomotor activity
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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.
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Directory of Open Access Journals (Sweden)
Martin Kyek
Full Text Available 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.
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Directory of Open Access Journals (Sweden)
Seratt Jessica
2006-06-01
Full Text Available Abstract 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
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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.
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Discrimination between micronuclei induced by spindle poisons and ...
African Journals Online (AJOL)
Discrimination between micronuclei induced by spindle poisons and clastogens by using toad bone marrow polychromatic erythrocytes. ... Egyptian Journal of Biology ... The used chemicals induced high percentages of micronuclei with variable sizes, which clarify the sensitivity of bone marrow cells of Bufo regularis to ...
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Photobleaching correction in fluorescence microscopy images
International Nuclear Information System (INIS)
Vicente, Nathalie B; Diaz Zamboni, Javier E; Adur, Javier F; Paravani, Enrique V; Casco, Victor H
2007-01-01
Fluorophores are used to detect molecular expression by highly specific antigen-antibody reactions in fluorescence microscopy techniques. A portion of the fluorophore emits fluorescence when irradiated with electromagnetic waves of particular wavelengths, enabling its detection. Photobleaching irreversibly destroys fluorophores stimulated by radiation within the excitation spectrum, thus eliminating potentially useful information. Since this process may not be completely prevented, techniques have been developed to slow it down or to correct resulting alterations (mainly, the decrease in fluorescent signal). In the present work, the correction by photobleaching curve was studied using E-cadherin (a cell-cell adhesion molecule) expression in Bufo arenarum embryos. Significant improvements were observed when applying this simple, inexpensive and fast technique
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Shibata, Yuki; Takeuchi, Hiro-Aki; Hasegawa, Takahiro; Suzuki, Masakazu; Tanaka, Shigeyasu; Hillyard, Stanley D; Nagai, Takatoshi
2011-09-01
Anuran amphibians obtain water by osmosis across their ventral skin. A specialized region in the pelvic skin of semiterrestrial species, termed the seat patch, contains aquaporins (AQPs) that become inserted into the apical plasma membrane of the epidermis following stimulation by arginine vasotocin (AVT) to facilitate rehydration. Two AVT-stimulated AQPs, AQP-h2 and AQP-h3, have been identified in the epidermis of seat patch skin of the Japanese tree frog, Hyla japonica, and show a high degree of homology with those of bufonid species. We used antibodies raised against AQP-h2 and AQP-h3 to characterize the expression of homologous AQPs in the skin of two species of toads that inhabit arid desert regions of southwestern North America. Western blot analysis of proteins gave positive results for AQP-h2-like proteins in the pelvic skin and also the urinary bladder of Anaxyrus (Bufo) punctatus while AQP-h3-like proteins were found in extracts from the pelvic skin and the more anterior ventral skin, but not the urinary bladder. Immunohistochemical observations showed both AQP-h2- and AQP-h3-like proteins were present in the apical membrane of skin from the pelvic skin of hydrated and dehydrated A. punctatus. Further stimulation by AVT or isoproterenol treatment of living toads was not evident. In contrast, skin from hydrated Incilius (Bufo) alvarius showed very weak labeling of AQP-h2- and AQP-h3-like proteins and labeling turned intense following stimulation by AVT. These results are similar to those of tree frogs and toads that occupy mesic habitats and suggest this pattern of AQP expression is the result of phylogenetic factors shared by hylid and bufonid anurans.
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DEFF Research Database (Denmark)
Allentoft, Morten Erik; 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...... of isolation by distance within major regions supported this apparent lack of a gene flow continuum. Indications of a genetic bottleneck were found in three populations. The analyses suggest that the remaining Bufo calamita populations in Denmark are genetically isolated, and represent independent units...... in a highly fragmented gene pool. Future conservation management of this species is discussed in light of these results....
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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
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Caracterización morfológica de larvas de anuros del Noroeste argentino
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Fabrezi, Marissa
1997-01-01
Full Text Available Se analizan caracteres morfológicos en larvas de catorce especies de anuros. Las especies analizadas son Bufo arenarum, B. paracnemis, Leptodadylus chaquensis, L. latinasus, Odontophrynus americanus, O. lavillai, Phrynohyas venulosa, Phyllomedusa sauvagii, Physalaemus biligonigerus, P. cuqui, Pleurodema borellii, P. tucumana, Scinax fuscovaria y S. nasica. Estas especies se desarrollan en charcas temporarias del Noroeste de Argentina. Se caracterizan las larvas de cada especie por el análisis de la morfología externa e interna, caracteres de la cavidad oral, condrocráneo y arcos viscerales. Algunos de estos aspectos morfológicos se discuten con las hipótesis propuestas acerca de larvas generalizadas. We have analyzed morphological characters in tadpoles of fourteen anuran species. The species considered are Bufo arenaum, B. paracnemis, Leptodactylus chaquensis, L. latinasus, Odontopbynus americanus, O.lavillai, Phrynohyas venulosa, Phyllomedusa sauvagii, Physalaemus biligonigerus, P. cuqui, Pleurodema borellii, P. tucumana, Scinax fuscovaria and S. nasica. They develop in similar temporary ponds of Northwestern of Argentina. We characterized the larvae of each species by the analyses on external morphology, internal oral features, chondrocranium and visceral archs. Some of these morphological aspects have been discussed with proposal hypotheses about generalized tadpoles.
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The role of adrenergic receptors in nicotine-induced hyperglycemia ...
African Journals Online (AJOL)
The role of adrenergic receptors in nicotine-induced hyperglycaemia has not been well studied in amphibians. Thus, this study investigates the effects of alpha and beta adrenergic receptor blockers in nicotine-induced hyperglycaemia in the common African toad Bufo regularis. Toads fasted for 24 h were anaesthetized with ...
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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.
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Ali, Sharique A; Naaz, Ishrat; Choudhary, Ram Kumar
2014-02-01
Reduced production of melanin by decreased or the absence of melanocytes leads to various hypopigmentation disorders, and the development of melanogenetic agents for photoprotection and hypopigmentation disorders is one of the top priority areas of research. Hence, the present study was carried out to elucidate the ability of berberine, a principal active ingredient present in the roots of the herb Berberis vulgaris to stimulate pigment dispersion in the isolated skin melanophores of the toad Bufo melanostictus. In the present study, mean melanophore size index of the isolated skin melanophores of B. melanostictus was assayed after treating with various concentrations of berberine. A marked melanin dispersion response leading to skin darkening was observed in the isolated melanophores of toad in response to berberine, which was found to be mediated through beta-2 adrenergic receptors. The physiologically significant dose-related melanin dispersion effects of berberine per se were found to be completely abolished by propranolol, which is a specific beta-2 adrenergic receptor blocker. These per se melanin dispersal effects were also found to be markedly potentiated by isoprenaline, which is a specific beta-adrenoceptor agonist. The results indicate that berberine causes a tremendous, dose-dependent, physiologically significant pigment dispersing in the isolated skin melanophores of B. melanostictus.
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Maria Auxiliadora de Sousa
1974-01-01
Full Text Available A ocorrência de hemagregarinas no sangue dos sapos que examinamos (Bufo crucifer, B. marinus e Melanophryniscus moreirae revelou-se extremamente rara; apenas um exemplar de B. crucifer procedente de Manguinhos (Rio de Janeiro, Guanabara apresentou-se parasitado. As formas sanguíneas encontradas eram intra-eritrocitárias, medindo em média 10,8/ 3,6µ; não as identificamos como trofozoítos ou gametócitos e discutimos este fato. As hemácias parasitadas tinham dimensões normais, porém podiam ter o núcleo deslocado. Supomos ser esta a primeira referência a hemogregarinas neste hospedeiro. Não encontramos identidade entre as formas que descrevemos e aquelas referidas em outras espécies de sapos; fornecemos uma lista das hemogregarinas achadas nestes hospedeiros. Denominamos provisoriamente os parasitos que encontramos Haemogregarina "sensu lato", até que novos dados sobre seu ciclo evolutivo sejam conhecidos.The occurrence of hemogregarines in the blood of Brazilian toads that we have examined (Bufo crucifer, B. Marinus and Melanophryniscus moreirae has displayed very scarce; only one specimen of B. crucifer from Manguinhos (Rio de Janeiro, Guanabara was infected. The blood forms that we found were intraerythrocytic, averaging 10,8 by 3,6µ; we did not differenciate them as thophozoites or as gametocytes and we discuss this fact. The infected erythrocytes were not hypertrophied and their nucleus was normal and sometimes displaced. We think that it is the first reference to hemogregarines in this host. We did not evidence identity among the forms that we described and those reported in other species of toads; we give a list of hemogregarines found in those hosts. We provisorily named the parasites that we found Haemogregarina "sensu lato", until new data about their life cycle become known.
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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.
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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.
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Wang, Ming; Chai, Lihong; Zhao, Hongfeng; Wu, Minyao; Wang, Hongyuan
2015-11-01
Chinese toad (Bufo gargarizans) tadpoles were exposed to nitrate (10, 50 and 100mg/L NO3-N) from the beginning of the larval period through metamorphic climax. We examined the effects of chronic nitrate exposure on metamorphosis, mortality, body size and thyroid gland. In addition, thyroid hormone (TH) levels, type II iodothyronine deiodinase (Dio2) and type III iodothyronine deiodinase (Dio3) mRNA levels were also measured to assess disruption of TH synthesis. Results showed that significant metamorphic delay and mortality increased were caused in larvae exposed to 100mg/L NO3-N. The larvae exposed to 100mg/L NO3-N clearly exhibited a greater reduction in thyroxine (T4) and 3,5,3'-triiodothyronine (T3) levels. Moreover, treatment with NO3-N induced down-regulation of Dio2 mRNA levels and up-regulation of Dio3 mRNA levels, reflecting the disruption of thyroid endocrine. It seems that increased mass and body size may be correlated with prolonged metamorphosis. Interestingly, we observed an exception that exposure to 100mg/L NO3-N did not exhibit remarkable alterations of thyroid gland size. Compared with control groups, 100mg/L NO3-N caused partial colloid depletion in the thyroid gland follicles. These results suggest that nitrate can act as a chemical stressor inducing retardation in development and metamorphosis. Therefore, we concluded that the presence of high concentrations nitrate can influence the growth, decline the survival, impair TH synthesis and induce metamorphosis retardation of B. gargarizans larvae. Copyright © 2015 Elsevier Ltd. All rights reserved.
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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.
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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.
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International Nuclear Information System (INIS)
Abugabr, H. E.; Elhussein, S. A.; Mahmoud, Z. N.
2009-01-01
The study revealed a well-built first line innate immunity system in Bufo Spp., the skin extracts illustrated a very active antibiotic attitude which inhibited the growth of human pathogenic bacteria species, Escherichia coli (ATCC 19615), staphylococcus aureus(ATCC29213) and streptococcus pyogenes (ATCC25922). Heat treatment of secretion supported the fact that the antibacterial components possess an enzymatic attitude. Gel filtration chromatography accompanied with sensitivity tests against S.aureus showed the existence of four groups responsible for antibacterial activity in the parotoid glands secretions.(Author)
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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)...
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Karyological and flow cytometric evidence of triploid specimens in Bufo viridis (Amphibia Anura
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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.
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The Effects of the Toxic Cyanobacterium Limnothrix (Strain AC0243 on Bufo marinus Larvae
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Olivia Daniels
2014-03-01
Full Text Available 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.
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The Effects of the Toxic Cyanobacterium Limnothrix (Strain AC0243) on Bufo marinus Larvae
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
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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.
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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.
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Serum and hepatic vitamin A levels in captive and wild marine toads (Bufo marinus).
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.
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Reacción de Galli Mainini para el diagnóstico precoz del embarazo
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Gilberto Angel Mejía
1949-11-01
el diagnóstico precoz del embarazo, se deriva del conjunto de trabajos realizados por Houssay y su escuela, quienes desde el año de 1922 venían trabajando en forma intensa e ininterrumpida, sobre anatomía histología y fisiología gonadales, observando las relaciones entre éstas y las gonadotrofinas en diversos batracios. En el año de 1929 hallaron la liberación de los espermatozoides en el testículo del Bufo arenarum Hensel, por la estimulación de las gonadotrofinas hipofisiarias y aunque numerosos trabajos se publicaron al respecto en los años posteriores, sólo en marzo de 1947 Carlos Galli Mainini publicó su primer trabajo, realizado sobre 19 casos, marcando el primer eslabón en esta reacción que ha sustituído a cuantas se han aplicado para el diagnóstico precoz del embarazo, por su exactitud y rapidez.
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Alimentación y fecundidad de Bufo variegatus (Anura: Bufonidae en Santa Cruz, Argentina
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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.
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Brodeur, Julie C; Sassone, Alina; Hermida, Gladys N; Codugnello, Nadia
2013-06-01
Despite of the various studies reporting on the subject, anticipating the impacts of the widely-used herbicide atrazine on anuran tadpoles metamorphosis remains complex as increases or decreases of larval period duration are almost as frequently reported as an absence of effect. The aim of the present study was to examine the effects of environmentally-relevant concentrations of atrazine (0.1, 1, 10, 100, and 1000μg/L) on the timings of metamorphosis and body size at metamorphosis in the common South American toad, Rhinella arenarum (Anura: bufonidae). None of the atrazine concentrations tested significantly altered survival. Low atrazine concentrations in the range of 1-100μg/L were found to accelerate developmental rate in a non-monotonic U-shaped concentration-response relationship. This observed acceleration of the metamorphic process occurred entirely between stages 25 and 39; treated tadpoles proceeding through metamorphosis as control animals beyond this point. Together with proceeding through metamorphosis at a faster rate, tadpoles exposed to atrazine concentrations in the range of 1-100μg/L furthermore transformed into significantly larger metamorphs than controls, the concentration-response curve taking the form of an inverted U in this case. The no observed effect concentration (NOEC) was 0.1μg atrazine/L for both size at metamorphosis and timings of metamorphosis. Tadpoles exposed to 100μg/L 17β-estradiol presented the exact same alterations of developmental rate and body size as those treated with 1, 10 and 100μg/L of atrazine. Elements of the experimental design that facilitated the detection of alterations of metamorphosis at low concentrations of atrazine are discussed, together with the ecological significance of those findings. Copyright © 2013 Elsevier Inc. All rights reserved.
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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 (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 must be cautiously used as indicators to assess environmental impact, mainly soil pollution. Results of the present study may be used as baseline data for any future analyses of the physiological impacts of environmental changes using toads as model organism.
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Assessment of pollution in road runoff using a Bufo viridis biological assay
International Nuclear Information System (INIS)
Dorchin, A.; Shanas, U.
2010-01-01
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.
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Assessment of pollution in road runoff using a Bufo viridis biological assay.
Dorchin, A; Shanas, U
2010-12-01
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. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Effect of guaianolides in the meiosis reinitiation of amphibian oocytes.
Zapata-Martínez, J; Sánchez-Toranzo, G; Chaín, F; Catalán, C A N; Bühler, M I
2017-02-01
Sesquiterpene lactones (STLs) are a large and structurally diverse group of plant metabolites generally found in the Asteraceae family. STLs exhibit a wide spectrum of biological activities and it is generally accepted that their major mechanism of action is the alkylation of the thiol groups of biological molecules. The guaianolides is one of various groups of STLs. Anti-tumour and anti-migraine effects, an allergenic agent, an inhibitor of smooth muscle cells and of meristematic cell proliferation are only a few of the most commonly reported activities of STLs. In amphibians, fully grown ovarian oocytes are arrested at the beginning of meiosis I. Under stimulus with progesterone, this meiotic arrest is released and meiosis progresses to metaphase II, a process known as oocyte maturation. There are previous records of the inhibitory effect of dehydroleucodin (DhL), a guaianolide lactone, on the progression of meiosis. It has been also shown that DhL and its 11,13-dihydroderivative (2H-DhL; a mixture of epimers at C-11) act as blockers of the resumption of meiosis in fully grown ovarian oocytes from the amphibian Rhinella arenarum (formerly classified as Bufo arenarum). The aim of this study was to analyze the effect of four closely related guaianolides, i.e., DhL, achillin, desacetoxymatricarin and estafietin as possible inhibitors of meiosis in oocytes of amphibians in vitro and discuss some structure-activity relationships. It was found that the inhibitory effect on meiosis resumption is greater when the lactone has two potentially reactive centres, either a α,β-α',β'-diunsaturated cyclopentanone moiety or an epoxide group plus an exo-methylene-γ-lactone function.
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Diazinon mediated biochemical changes in the African toad (Bufo regularis
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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.
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Bianchi, Catherine M; Johnson, Cassidy B; Howard, Lauren L; Crump, Paul
2014-09-01
Effective disease monitoring and prevention is critical to the success of captive amphibian care. Nematodes, including the genera Rhabdias and Strongyloides, are known to contribute to mortality in captive amphibians and have been identified in the Houston Zoo's endangered Houston toad (Bufo [Anaxyrus] houstonensis) captive assurance colony. Five years of fecal data for the toad colony were compiled and analyzed in order to investigate the efficacy of two anthelminthic medications, fenbendazole (FBZ) and levamisole (LMS), which were used to control nematode infections. Both FBZ (dusted onto food items) and topical LMS (6.5 to 13.5 mg/kg) significantly reduced the number of nematode eggs, larvae, and adults observed by fecal parasitologic examination. There were no significant differences between treatments, and egg reappearance periods were difficult to compare as a result of low sample size. No adverse effects from either anthelminthic treatment were observed. Both topical LMS and oral FBZ appear to be safe and efficacious treatments for the reduction of the internal nematode burden in captive Houston toads.
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Chao, Wu; Zhang, Yuhui; Chai, Lihong; Wang, Hongyuan
2018-06-10
Endochondral ossification, the process by which most of the bone is formed, is regulated by many specific groups of molecules and extracellular matrix components. Hind limb of Bufo gargarizans is a model to study endochondral ossification during metamorphosis. Chinese toad (Bufo gargarizans) were exposed to different fluoride concentrations (0, 1, 5, 10 and 20 mg L -1 ) from G3 to G42. The development of hind limb of B. gargarizans was observed using the double staining methodology. The transcriptome of hind limb of B. gargarizans was conducted using RNA-seq approach, and differentially expressed gene was also validated. In addition, the location of Sox9 and Ihh in the growth cartilage was determined using in situ hybridization. Our results showed that 5 mg L -1 stimulated bone mineralization, while 10 and 20 mg L -1 exposure could inhibit the tibio-fibula, tarsus and metacarpals ossification. Besides, 10 mg F/L treatment could down-regulate Ihh, Sox9, D2, D3, TRα, TRβ, Wnt10, FGF3 and BMP6 expression, while up-regulate ObRb and HHAT mRNA expression in the hind limb of B. gargarizans. Transcript level changes of Ihh, Sox9, D2, D3, TRα, TRβ, Wnt10, FGF3 and BMP6 were consistent with the results of RT-qPCR. In situ hybridization revealed that Ihh was expressed in prehypertrophic chondrocytes, while Sox9 was abundantly expressed in proliferous, prehypertrophic and hypertrophic chondrocytes. However, 10 mg F-/L did not cause any affect in the location of the Ihh and Sox9 mRNA. Therefore, high concentration of fluoride could affect the ossification-related genes mRNA expression and then inhibit the endochondral ossification. The present study thus will greatly contribute to our understanding of the effect of environmental contaminant on ossification in amphibian. Copyright © 2018 Elsevier B.V. All rights reserved.
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ALIMENTACIÓN DE BUFO MARINUS (LINNAEUS, 1758 (BUFONIDAE: ANURA, EN UNA LOCALIDAD DE SUCRE, COLOMBIA
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Sampedro Alcides
2011-12-01
Full Text Available Se realizaron recolectas nocturnas de Bufo marinus en una localidad del departamento de Sucre. Se recolectaron 197 ejemplares, de los cuales 128 fueron hembras y 69 machos. Los ejemplares fueron medidos y pesados y se les practicó una disección para extraer el estómago y determinar aspectos cualitativos (tipo de presas y cuantitativos (número y tamaño de presas. Insectos del orden Hymenoptera fueron las presas de mayor importancia. Los individuos de mayor tamaño ingieren presas más grandes y en menor cantidad mientras que los de menor talla, presas pequeñas, pero en mayor cantidad. La proporción del peso del contenido estomacal en relación con el peso corporal, tanto para hembras como para machos fue similar (6%. Esta especie no parece representar un peligro para la fauna nativa en el departamento de Sucre.
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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.
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The uptake of 14C-glycine to Bufo vulgaris formosus (Boulenger) larva at metamorphosis
International Nuclear Information System (INIS)
Hasegawa, Hitoshi; Tanaka, Haruo; Ishiguro, Shigeru; Nonoyama, Kiyoshi; Nakagawa, Harumi.
1981-01-01
With the eggs of Bufo vulgaris formosus (Boulenger) immediately after fertilization, the larvae in the 50 ml solution containing 1 ml of 14 C-glycine were developed to the end of metamorphosis. Measurements were made on the length of body, tail, fore limb and hind leg through the stages of tail degeneration and vestige. The radioactivity of the cut off fore limbs, hind legs, tails and head trunks was measured with a scintillation counter, and the 10 μ sections of the samples were used for autoradiography. The larvae uptook orally 14 C-glycine to the organs of cell tissues. On the basis of the reports of the autolysis of tails and the activation of lysosome enzyme in metamorphosis and on the uptake of 14 C-leucine and 14 C-proline to four legs by other workers, and on the present results, the free amino acids formed from the autolysis of tails were utilized for the recomposition of organ protein synthesis in the metamorphosis of the amphibians. (J.P.N.)
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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.
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Hanner, R H; Ryan, G B
1980-01-01
Renal juxtaglomerular regions were examined in the axolotl (Ambystoma mexicanum and toad (Bufo marinus). Prominent granulated peripolar epithelial cells were found surrounding the origin of the glomerular tuft in the axolotl. These cells resembled the peripolar cells recently discovered in mammalian species. They contained multiple electron-dense cytoplasmic granules, some of which showed a paracrystalline substructure and signs of exocytoxic activity. Such cells were difficult to find and smaller in the toad. In contrast, granulated juxtaglomerular arteriolar myoephithelial cells were much more readily found and larger in the toad than in the axolotl. No consistent differences were noted in juxtaglomerular cells or their granules in response to changes in environmental chloride concentration. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:7410189
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Wassersug, R J; Feder, M E
1983-07-01
Larvae of the anurans Rana berlandieri and Xenopus laevis have lungs and can breathe air as well as irrigate buccal and pharyngeal surfaces for aquatic respiration. Larvae of Bufo americanus lack lungs until just before metamorphosis and are obligately aquatic. We examined the relationship between the locomotor stamina (time to fatigue), aquatic oxygen concentration, body size, and respiratory behaviour of swimming larvae of these species, with the following results: Stamina is size-dependent in all three species. Aquatic hypoxia reduces stamina in larvae of all three species, but most conspicuously in Bufo. Breathing air increases stamina in Rana larvae, especially in large animals and under aquatic hypoxia. In contrast to Rana larvae, Xenopus larvae swimming in normoxic water undergo a reduction in stamina when allowed to breathe air. In hypoxic water, aerial respiration moderates the reduction in stamina seen in Xenopus larvae. Branchial irrigation is associated with increased stamina in Xenopus, and is increased under hypoxia and at high swimming velocities. Respiratory demand, buoyancy and the drag associated with branchial irrigation all affect respiratory behaviour in Xenopus larvae. The great amount of interspecific variation in the relationship between respiratory behaviour and stamina reveals the importance of measuring performance directly when attempting to interpret the functional significance of respiratory structures and behaviour.
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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
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Rowson, Angela D.; Obringer, Amy R.; Roth, Terri L.
2001-01-01
As many as 20% of all assessed amphibian species are threatened with extinction, and captive breeding programs are becoming important components of conservation strategies for this taxon. For some species, exogenous hormone administration has been integrated into breeding protocols to improve propagation. However, most treatments are administered by an intraperitoneal injection that can be associated with some risks. The general goal of this study was to identify a non-invasive method of applying luteinizing hormone-releasing hormone (LHRH), which reliably induces sperm release in toads. Specific objectives were to 1) test the spermiation response after topical application of different LHRH doses to the abdominal seat region, 2) evaluate the effects of adding the absorption enhancers dimethyl sulfoxide (DMSO), acetone, and glyceryl monocaprylate (GMC) to the LHRH, 3) assess the spermiation response after oral delivery of LHRH in a mealworm vehicle, and 4) compare sperm characteristics and spermiation responses to treatments in two different toad species. Male American (n = 9) and Gulf Coast (n = 7) toads were rotated systematically through a series of treatments. Urine was collected and evaluated for the presence of sperm at 0, 3, 7, 12, and 24 hours post-treatment. There were no statistical differences in spermiation induction or sperm characteristics between American and Gulf Coast toads after the treatments. Oral administration of 100 &mgr;g LHRH was occasionally successful in inducing spermiation, but results appeared largely unreliable. Ventral dermal application of 100 or 10 &mgr;g LHRH in 40% DMSO were more effective (P Zoo Biol 20:63-74, 2001. Copyright 2001 Wiley-Liss, Inc.
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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.
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Ultrastructural and Molecular Changes in the Developing Small Intestine of the Toad Bufo regularis
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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.
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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.
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Effects of copper on growth, metamorphosis and endocrine disruption of Bufo gargarizans larvae.
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.
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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.
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Toxic effects of NH4+-N on embryonic development of Bufo gargarizans and Rana chensinensis.
Deng, Hongzhang; Chai, Lihong; Luo, Pingping; Zhou, Meimei; Nover, Daniel; Zhao, Xiaohong
2017-09-01
Although nitrogen fertilizer is commonly used worldwide, little information is currently available about NH 4 + -N toxicity on amphibians. This study determined the acute and chronic toxic effects of NH 4 + -N on two native Chinese amphibian species (Bufo gargarizans and Rana chensinensis), and compared the negative sensitivity of different embryos to NH 4 + -N. Static renewal aqueous exposures were performed using B. gargarizans and R. chensinensis embryos at Gosner stage 2 over 96 h. In terms of 96 h-LC 50 , B. gargarizans and R. chensinensis embryos had significantly different responses to NH 4 + -N, and the latter was more sensitive to NH 4 + -N than the former. In the chronic toxicity test, exposure to 10 mg L -1 NH 4 + -N or higher significantly decreased the hatching rate of embryos in both species. Significant increases in the abnormality rate of embryos at 50 mg L -1 NH 4 + -N or higher were observed and morphological abnormalities were characterized by axial flexures, yolk sac edema, and hyperplasia in both species. Additionally, the total length of embryos decreased in a dose-dependent manner after exposure to NH 4 + -N. The results indicate that NH 4 + -N exposure can increase abnormality and inhibit the hatching and development of embryos in B. gargarizans and R. chensinensis. Copyright © 2017 Elsevier Ltd. All rights reserved.
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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.
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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.
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Prostaglandins as mediators of acidification in the urinary bladder of Bufo marinus
International Nuclear Information System (INIS)
Frazier, L.W.; Yorio, T.
1990-01-01
Experiments were performed to determine whether prostaglandins (PG) play a role in H+ and NH4+ excretion in the urinary bladder of Bufo marinus. Ten paired hemibladders from normal toads were mounted in chambers. One was control and the other hemibladder received PGE2 in the serosal medium (10(-5) M). H+ excretion was measured by change in pH in the mucosal fluid and reported in units of nmol (100 mg tissue)-1 (min)-1. NH4+ excretion was measured colorimetrically and reported in the same units. The control group H+ excretion was 8.4 +/- 1.67, while the experimental group was 16.3 +/- 2.64 (P less than 0.01). The NH4+ excretion in the experimental and control group was not significantly different. Bladders from toads in a 48-hr NH4+Cl acidosis (metabolic) did not demonstrate this response to PGE2 (P greater than 0.30). Toads were put in metabolic acidosis by gavaging with 10 ml of 120 mM NH4+Cl 3 x day for 2 days. In another experiment, we measured levels of PG in bladders from control (N) and animals placed in metabolic acidosis (MA). Bladders were removed from the respective toad, homogenized, extracted, and PG separated using high-pressure liquid chromatography and quantified against PG standards. The results are reported in ng (mg tissue)-1. PGE2 fraction in N was 1.09 +/- 0.14 and in MA was 3.21 +/- 0.63 (P less than 0.01). PGF1 alpha, F2 alpha and I2 were not significantly different in N and MA toads. Bladders were also removed from N and MA toads, and incubated in Ringer's solution containing [3H]arachidonic acid (0.2 microCi/ml) at 25 degrees C for 2 hr. Bladders were then extracted for PG and the extracts separated by thin layer chromatography. PG were identified using standards and autoradiography, scraped from plates, and counted in a scintillation detector. The results are reported in cpm/mg tissue x hr +/- SEM
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Influence of nitric oxide on histamine and carbachol – induced ...
African Journals Online (AJOL)
The study aimed to determine the influence of nitric oxide (NO) on the action of histamine and carbachol on acid secretion in the common African toad – Bufo regularis. Gastric acidity was determined by titration method. The acid secretion was determined when nitric oxide was absent following administration of NO synthase ...
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Phospholipid transfer activities in toad oocytes and developing embryos
International Nuclear Information System (INIS)
Rusinol, A.; Salomon, R.A.; Bloj, B.
1987-01-01
The role of lipid transfer proteins during plasma membrane biogenesis was explored. Developing amphibia embryos were used because during their growth an active plasma membrane biosynthesis occurs together with negligible mitochondrial and endoplasmic reticulum proliferation. Sonicated vesicles, containing 14 C-labeled phospholipids and 3 H-labeled triolein, as donor particles and cross-linked erythrocyte ghosts as acceptor particles were used to measure phospholipid transfer activities in unfertilized oocytes and in developing embryos of the toad Bufo arenarum. Phosphatidylcholine transfer activity in pH 5.1 supernatant of unfertilized oocytes was 8-fold higher than the activity found in female toad liver supernatant, but dropped steadily after fertilization. After 20 hr of development, at the stage of late blastula, the phosphatidylcholine transfer activity had dropped 4-fold. Unfertilized oocyte supernatant exhibited phosphatidylinositol and phosphatidylethanolamine transfer activity also, but at the late blastula stage the former had dropped 18-fold and the latter was no longer detectable under our assay conditions. Our results show that fertilization does not trigger a phospholipid transport process catalyzed by lipid transfer proteins. Moreover, they imply that 75% of the phosphatidylcholine transfer activity and more than 95% of the phosphatidylinositol and phosphatidylethanolamine transfer activities present in pH 5.1 supernatants of unfertilized oocytes may not be essential for toad embryo development. Our findings do not rule out, however, that a phosphatidylcholine-specific lipid transfer protein could be required for embryo early growth
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Bionda, Clarisa; Lajmanovich, Rafael; Salas, Nancy; Martino, Adolfo; di Tada, Ismael
2013-09-01
The advancing agricultural frontier has led to an important loss of natural habitats, with significant consequences for biodiversity. The demography for two species of anurans, Physalaemus biligonigerus and Rhinella arenarum, both associated with agricultural systems in the central region of the C6rdoba Province, were analyzed and compared in this study. Four sites were sampled: three agroecosystems with different alteration degrees (C1, C2 and SM1) and a fourth site not cultivated (SM2). The sampling was conducted during two reproductive periods, from September 2008 to April 2009 and September 2009 to April 2010. Individuals were captured using live pitfall traps for the metamorphic, juveniles and adults; and visual encounter survey, for the capture of eggs and larvae. With the abundance data, the survival for each age class was estimated using the KNM method (Kiritani Nakasuki Manly). With survival rates and fertility population, Leslie matrices were elaborated to obtain a quantitative projection of the population size. Altered environments showed lower eggs and larvae survival. Population projections were favorable in the site SM2 and were less favorable and a tendency to extinction, in sites dominated by crops. This study showed that the agroecosystems of this region are possibly inhospitable environments for reproduction and survival of the species studied. The aquatic stages in the life cycle of both species would be the more affected, since water bodies deterioration is present or may occur in those areas. We can recognize species-specific effects of agricultural ecosystems; P. biligonigerus was the most affected species, possibly because of their life histories and habitat requirements. We suggested that environmental degradation caused by the cropland in the central region of Argentina would impact on the demographics of the anuran populations in the area.
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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.
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Hansen, L.J.; Fabacher, D.L.; Calfee, R.
2002-01-01
Background. Previous studies have suggested that Ultraviolet B (UVB) radiation may play a role in amphibian population declines. Some of these studies also indicate that egg hatching success is unaltered in some species of anurans as a result of UVB exposure. It has been proposed that the egg mass jelly provides photoprotection to the developing embryos. Methods. Direct spectrophotometric scans of egg jelly, scans of egg jelly methanol extracts, and experimental manipulation in a solar simulator during development were all used to assess the role of egg mass jelly as a photoprotective agent. Results/Discussion. For Hyla regilla, scans of egg jelly and methanolic extracts (for mycosporine-like amino acid content) both displayed no absorption in the UV range. Experimental manipulation (removal of egg mass jelly) with both Hyla regilla and Bufo canorus egg masses in a solar simulator demonstrated that egg mass jelly played no apparent role in photoprotection of either of these species. Conclusions. Based on the results in this study it seems unlikely that the egg jelly coat is playing a crucial role in protecting developing embryos from the impact of UVB radiation.
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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.
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Directory of Open Access Journals (Sweden)
Carolina E. Rosenberg
2007-07-01
Full Text Available There is evidence that environmental metal levels affect the immune function. In the particular case of the impact of heavy metals, information available suggests that the immune system is a target for low-dose Pb exposure. Among vertebrates it was shown that amphibians are capable of forming antibodies against a variety of antigens, causing several responses such as anaphylactic response and rejecting grafts. In this study, the production of antibodies was assessed against sheep red blood cells (SRBC in the anuran Bufo arenarum after six weekly injections of sublethal doses of lead (50 mg.kg-1, as lead acetate. Natural antibodies (natural heteroagglutinins were also quantified against SRBC. Both assessments were carried out employing an ELISA method developed to this end, measuring absorbance (A. For natural anti-SRBC antibodies in both control (C and Pb treated (T toads, there was a non significant tendency to increase the initial absorbances (C initial: 0.69±0.39 A; T initial: 0.54±0.30 A, relative to those registered at the end of the experiments (C final: 0.89±0.49 A; T final: 0.76±0.31A; the T/C ratios also did not show changes. The only significant difference was found between initial and final samples from lead-treated toads (pExiste evidencia de que los niveles de metal ambientales afectan la función inmune. En el caso particular del impacto de metales pesados, la información disponible sugiere que el sistema inmune es un blanco para la exposición a bajas dosis de Pb. Entre los vertebrados, se ha mostrado que los anfibios son capaces de formar anticuerpos contra una variedad de antígenos, que causan diversas respuestas, tales como respuesta anafiláctica y rechazo de injertos. En este estudio, la producción de anticuerpos fue evaluada contra eritrocitos de oveja (EO en el anuro Bufo arenarum, luego de seis inyecciones semanales de dosis subletales de plomo (50 mg.kg-1, como acetato de Pb. Los anticuerpos naturales
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Directory of Open Access Journals (Sweden)
Salas, Nancy E.
1998-01-01
Full Text Available El conocimiento de las características del canto de los anfibios constituye un importante elemento para la identificación de las especies que puede ser empleado como herramienta para prácticas estandarizadas de monitoreo. En el presente trabajo se resaltan las diferencias eto-ecológicas más notables (hábitat de reproducción, sitio de canto, actividad estacional y diaria de aquellas especies que integran las comunidades del sur de la Provincia Córdoba y se proporciona una clasificación de los cantos nupciales. La batracofauna del área de llanura del sur-este de la provincia de Córdoba está representada por 9 especies de leptodactílidos correspondientes a 5 géneros (Leptodactylus gracilis, L. mystacinus, L. latinasus latinasus, L. ocellatus, Pleurodema tucumanum, Physalaemus biligonigerus, Odontophrynus americanus, Ceratophrys cranwelli y C. ornata, 2 especies de bufónidos (Bufo arenarum y B. fernandezae y un hílido (Hyla pulchella pulchella. Los registros acústicos obtenidos en el campo durante el período reproductivo fueron analizados a través de programas de análisis digital de sonido, comparándose los siguientes parámetros: frecuencia dominante, duración del canto, intervalo entre cantos; se realizaron además descripciones respecto del tipo de canto y su modulación. Se reconocieron tres tipos de cantos básicos segun su duración, categoría que fue subdividida por la forma de la imagen oscilográfica. El resultado de este análisis establece que existen notables diferencias entre los cantos nupciales, principalmente a nivel de rangos de frecuencia dominante y duración de las emisiones. Esta partición del espacio sonoro representa un mecanismo de aislamiento reproductivo que minimiza la interacción entre especies simpátricas cuya reproducción muestra también un solapamiento temporal. Knowledge of the characteristics of amphibian calls is essential for species identification, and may be used as a tool in
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Molecular cloning and analysis of Myc modulator 1 (Mm-1 from Bufo gargarizans (Amphibia: Anura
Directory of Open Access Journals (Sweden)
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.
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Nomenclatural notes on living and fossil amphibians
Directory of Open Access Journals (Sweden)
Martín, C.
2012-06-01
Full Text Available A review of extinct and living amphibians known from fossils (Allocaudata, Anura and Caudata has revealed several cases that require nomenclatural changes in order to stabilize the taxonomy of the group. Nomenclatural changes include homonym replacements, corrections of spelling variants and authorships, name availabilities, and in particular, the proposal of new combinations. These changes will allow the incorporation of some palaeontological taxa to the current evolutionary models of relationship of modern forms based on molecular phylogenies. Rana cadurcorum for Rana plicata Filhol, 1877, Rana auscitana for Rana pygmaea Lartet, 1851, and Rana sendoa for Rana robusta Brunner, 1956. Anchylorana Taylor, 1942 is considered a new synonym of Lithobates Fitzinger, 1843. New combinations proposed are: Anaxyrus defensor for Bufo defensor Meylan, 2005; Anaxyrus hibbardi for Bufo hibbardi Taylor, 1937; Anaxyrus pliocompactilis for Bufo pliocompactilis Wilson, 1968; Anaxyrus repentinus for Bufo repentinus Tihen, 1962; Anaxyrus rexroadensis for Bufo rexroadensis Tihen, 1962; Anaxyrus spongifrons for Bufo spongifrons Tihen, 1962; Anaxyrus suspectus for Bufo suspectus Tihen, 1962; Anaxyrus tiheni for Bufo tiheni Auffenberg, 1957; Anaxyrus valentinensis for Bufo valentinensis Estes et Tihen, 1964; Ichthyosaura wintershofi for Triturus wintershofi Lunau, 1950; Incilius praevius for Bufo praevius Tihen, 1951; Lithobates bucella for Rana bucella Holman, 1965; Lithobates dubitus for Anchylorana dubita Taylor, 1942; Lithobates fayeae for Rana fayeae Taylor, 1942; Lithobates miocenicus for Rana miocenica Holman, 1965; Lithobates moorei for Anchylorana moorei Taylor, 1942; Lithobates parvissimus for Rana parvissima
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Observations on the breeding of toads in a restricted habitat ...
African Journals Online (AJOL)
The population consisted of two kinds of toads: Bufo gutturalis Power and a hybrid population believed to be derived from crosses between Bufo gutturalis Power and Bufo rangeri Hewitt. Individual animals can be distinguished by differences in the shape of dark spots on their backs. A record was made of every pair found ...
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Radiation-induced changes of the developing nervous system of amphibians
International Nuclear Information System (INIS)
Schneider, M.
1986-01-01
The nervous system of amphibians (Xenopus laevis and Bufo) is of an outstanding sensitivity against irradiation in the early periods of its tissue induction and development. This is descriptively shown by various pathological disturbances. Irradiated series showed a protracted course of development. The brains obtains lower relative weights and diminished absolute lengths although the body weight remained nearly constant. The distribution of pigmentation in the brains of treated animals was changed. This indicated radiation-induced disturbances. Further, the significance of pigmentation pattern for a distinct evaluation of histological effects is also confirmed by a coincidence between the gross visible anomalies of the brain and the number of pigment-sites. Examples of malformation are given by aplasias, hypoplasias, hyperplasias up to cases of cyclopia. In the peripheral nervous system of Xenopus the neuromuscular junctions of the musculus interhyoideus were examined. The majority of neural endplates in the irradiated cases showed a loss of Schwann cells. As a consequence a diffusion of the transmitter acetylcholine in the endplate-region must be suggested. Accordingly, the morphological compensation reaction was seen in a thickening and sprouting. (orig.)
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International Nuclear Information System (INIS)
Metts, Brian S.; Buhlmann, Kurt A.; Scott, David E.; Tuberville, Tracey D.; Hopkins, William A.
2012-01-01
We conducted a mesocosm study to assess the individual and interactive effects of previous maternal exposure and larval exposure to trace element-laden sediments on southern toads (Bufo terrestris). Previous maternal exposure to coal combustion wastes (CCW) reduced larval survival to metamorphosis up to 57% compared to larvae of unexposed females. Larvae reared on CCW accumulated significant concentrations of trace elements resulting in extended larval periods, reduced growth rates, and reduced mass at metamorphosis. However, the effects were dependent on age of sediments, suggesting the effects of contaminants from CCW may be partially ameliorated over time through the reduced bioavailability of trace elements in aged CCW. Most importantly, maternal exposure to contaminants coupled with larval exposure to fresh CCW interacted to reduce survival to metamorphosis by 85% compared to reference conditions. Our study yields further evidence that disposal of CCW in aquatic basins potentially creates ecological traps for some amphibian populations. - Highlights: ► The interaction of maternal exposure and larval exposure to CCW reduced survival. ► Previous maternal exposure to CCW had a latent effect on survival to metamorphosis. ► Larval southern toads exposed to CCW experienced prolonged larval periods. ► Larval southern toads exposed to CCW had reduced growth rates. ► Larval southern toads exposed to CCW had reduced mass at metamorphosis. - Maternal and environmental exposure to coal combustion wastes interact to decrease survival in larval amphibians.
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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.
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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.
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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.
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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.
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Lifescience Database Archive (English)
Full Text Available D06750 Crude ... Drug Toad venom (JP17) Hellebrin [CPD:C08868], Resibufogenin [CPD...:C17058], Cinobufagin [CPD:C16931], Bufalin [CPD:C16922], Bufotalin [CPD:C16923], Cinobufotalin [CPD:C16932], Gamabufo...C16921], Cardenolides, Bufotenine [CPD:C08299], Bufotenidine [CPD:C13664], Epiren...aginol, Marinobufagin, Resibufagin, Serotonine, Bufothionine, Dehydrobufotenine, Bufotoxin, Cholesterol [CPD...terol [CPD:C01694], Campesterol [CPD:C01789], Sitosterol [CPD:C01753] ... Bufo bufo gargagrizans [TAX:30331], Bufo
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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.
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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.
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Salida de campo a Orihuela del Tremedal (Teruel) entre el 14 y el 16 de julio de 1952
Valverde Gómez, José Antonio, 1926-2003
2008-01-01
Salida de campo del autor y Francisco Bernis a Orihuela del Tremedal, en Teruel, entre el 14 y el 16 de julio de 1952, de la que se anotaron observaciones sobre los siguientes anfibios: Alytes sp. (Sapo partero), Bufo bufo (Sapo común, llamado B.vulgaris por el autor), Epidalea calamita (Sapo corredor, llamado Bufo calamita por el autor) y Hyla sp. (Ranita), los siguientes reptiles: Chalcides sp. (Eslizón, también llamado Eliso por el autor), Podarcis muralis (Lagartija roquera, llamada Lac...
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Factors limiting the recovery of boreal toads (Bufo b. boreas)
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
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Directory of Open Access Journals (Sweden)
Teng-Lang Yu
Full Text Available 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.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.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 clades between W and E of B
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J-GLOBAL MeSH Dictionary: Ｂｕｆｏ ｂｕｆｏ [MeCab user dictionary for science technology term[Archive
Lifescience Database Archive (English)
Full Text Available MeCab user dictionary for science technology term Ｂｕｆｏ ｂｕｆｏ 名詞 一般 * * * * Bufo bufo ... MeSH D002023 200906035471563603 C LS05 UNKNOWN_2 Ｂｕｆｏ ｂｕｆｏ
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Eidietis, Laura
2006-04-01
I described the tactile-stimulated startle response (TSR) of wood frog (Rana sylvatica), bullfrog (Rana catesbeiana), and American toad (Bufo americanus) tadpoles. One purpose was to rank species in terms of maximum acceleration performance. Also, I tested whether anatomical indicators of performance potential were predictive of realized performance. TSRs were elicited in a laboratory setting, filmed at 250 Hz, and digitally analyzed. TSRs began with two, initial body curls during which tadpoles showed a broad spectrum of movement patterns. TSR performance was quantified by maximum linear acceleration and maximum rotational acceleration of the head/body, both of which tended to occur immediately upon initiation of motion ( wood frog > American toad. The species' rank order for the anatomical indicator of rotational acceleration potential was bullfrog > wood frog = American toad. Thus, the anatomical indicators roughly predicted the rank order of interspecific average performance. However, the anatomical indicators did not correlate with individual tadpole performance. Variability in behavioral patterns may obscure the connection between anatomy and performance. This is seen in the current lack of intraspecific correlation between a morphological indicator of acceleration capacity and acceleration performance.
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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 = -...
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Directory of Open Access Journals (Sweden)
Brum Zorrilla N.
1973-09-01
Full Text Available Karyotypes of eight of South American Bufonidae were studied: B.ictericus, B. spinulosus spinulosus, B. arenarum, B. g. fernandezae, B. g. d'orbignyi, B. crucifer, B. paracnemis and B. marinus. In all species 2n = 22 chromosomes were found. Neither heteromorphic pairs of chromosomes nor bivalents with characteristic morphology and behavior of sex chromosomesduring male meiosis were observed in any species.Karyotypes of eight of South American Bufonidae were studied: B.ictericus, B. spinulosus spinulosus, B. arenarum, B. g. fernandezae, B. g. d'orbignyi, B. crucifer, B. paracnemis and B. marinus. In all species 2n = 22 chromosomes were found. Neither heteromorphic pairs of chromosomes nor bivalents with characteristic morphology and behavior of sex chromosomesduring male meiosis were observed in any species.
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Central thermoregulatory effects of lactate in the toad Bufo paracnemis.
Branco, L G; Steiner, A A
1999-04-01
Hypoxia induces a regulated decrease in body temperature (Tb; anapyrexia) in organisms ranging from protozoans to mammals, but very little is known about the mechanisms involved. Several candidates have been suggested to mediate hypoxia-induced anapyrexia, among them lactate, which is a classical compansion of hypoxic stress in vertebrates. The present study was designed to assess the central thermoregulatory effects of lactate in Bujo paracnemis. Toads equipped with a temperature probe were tested over a thermal gradient (10-40 degrees C). Lactate injected systemically (4.0 mmol kg-1) caused a significant reduction of Tb from 24.6 +/- 2.1 to 17.4 +/- 3.9 degrees C. To assess the role of central thermoregulatory mechanisms, a lower dose (0.4 mmol kg-1) of lactate was injected into the fourth cerebral ventricle or systemically. Intracerebroventricular injection of lactate caused a similar decrease in Tb, whereas systemic injection caused no change. The data indicate that lactate may play a role in hypoxia-induced anapyrexia in central rather than peripheral sites.
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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-...
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induced gastric acid secretion in the common african toad – bufo
African Journals Online (AJOL)
admin
supported by the report of Sitmewoka (2000) which showed that absence of NO inhibits the secretion of gastric acid. However, Kato et al. (1998) observed that either exogenous or endogenous NO has inhibitory action on gastric acid secretion in mammals. This observation was supported by. Takeuchi et al. (1994) who also ...
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Macleod, G T; Dickens, P A; Bennett, M R
2001-04-01
A study has been made of the formation and regression of synapses with respect to Schwann cells at the ends of motor nerve terminal branches in mature toad (Bufo marinus) muscle. Synapse formation and regression, as inferred from the appearance and loss of N-(3-triethylammoniumpropyl)-4-(4-(dibutylamino)styryl) pyridinium dibromide (FM1-43)-stained vesicle clusters, occurred at the ends of terminal branches over a 16 hr period. Multiple microelectrodes placed in an array about FM1-43 blobs at the ends of terminal branches detected the electrical signs of neurotransmitter being released onto receptors. Injection of a calcium indicator (Oregon Green 488 BAPTA-1) into the motor nerve with subsequent imaging of the calcium transients, in response to stimulation, often showed a reduced calcium influx in the ends of terminal branches. Injection of a fluorescent dye into motor nerves revealed the full extent of their terminal branches and growing processes. Injection of the terminal Schwann cells (TSCs) often revealed pseudopodial TSC processes up to 10-microm-long. Imaging of these TSC processes over minutes or hours showed that they were highly labile and capable of extending several micrometers in a few minutes. Injection of motor nerve terminals with a different dye to that injected into their TSCs revealed that terminal processes sometimes followed the TSC processes over a few hours. It is suggested that the ends of motor nerve terminals in vivo are in a constant state of remodeling through the formation and regression of processes, that TSC processes guide the remodeling, and that it can occur over a relatively short period of time.
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Purwaningsih, Endang; Dewi, Kartika; Hasegawa, Hideo
2015-06-24
During a survey on the parasites of amphibians of Indonesia, toads (30 Bufo melanostictus) and 246 frogs (213 Fejervarya cancrivora, 11 F. limnocharis, 22 Rana macrodon from West Java and 68 F. cancrivora from Central Java) were examined for parasitic nematodes. Three species of nematodes were found and described, i.e. Meteterakis wonosoboensis n. sp. from Fejervaria cancrivora; Meteterakis japonica from Bufo melanostictus, F. cancrivora and F. limnocharis; and Chabaudus sp. from F. cancrivora, F. limnocharis and Rana macrodon. Meteterakis wonosoboensis n. sp. is distinguished from other species of the genus by the length and shape of spicules, the number of caudal papillae, the presence of gubernaculum in male and the presence of vulval flap in female. Bufo melanostictus and Java are recorded as new host and locality for M. japonica, respectively.
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Directory of Open Access Journals (Sweden)
Jörn F Gerchen
Full Text Available 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.
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Amphibians of the Simbruini Mountains (Latium, Central Italy
Directory of Open Access Journals (Sweden)
Pierangelo Crucitti
2010-07-01
Full Text Available Little attention has been paid to the herpetological fauna of the Simbruini Mountains Regional Park, Latium (Central Italy. In this study, we surveyed 50 sites in the course of about ten years of field research, especially during the period 2005-2008. Nine amphibian species, four Caudata and five Anura, 60.0% out of the 15 amphibian species so far observed in Latium, were discovered in the protected area: Salamandra salamandra, Salamandrina perspicillata, Lissotriton vulgaris, Triturus carnifex, Bombina pachypus, Bufo balearicus, Bufo bufo, Rana dalmatina, Rana italica. Physiography of sites has been detailed together with potential threatening patterns. For each species the following topics have been discussed; ecology of sites, altitudinal distribution, phenology, sintopy. Salamandra salamandra and Bombina pachypus are at higher risk. The importance of the maintenance of artificial/natural water bodies for the conservation management of amphibian population of this territory is discussed.
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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
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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.
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Detection of the emerging amphibian pathogens Batrachochytrium dendrobatidis and ranavirus in Russia
Reshetnikov, Andrey N.; Chestnut, Tara E.; Brunner, Jesse L.; Charles, Kaylene M.; Nebergall, Emily E.; Olson, Deanna H.
2014-01-01
In a population of the European common toad Bufo bufo from a rural pond in the region of Lake Glubokoe Regional Reserve in Moscow province, Russia, unexplained mass mortality events involving larvae and metamorphs have been observed over a monitoring period of >20 yr. We tested toads from this and a nearby site for the emerging amphibian pathogens Batrachochytrium dendrobatidis (Bd) and ranavirus (Rv). Both pathogens were detected, and at the rural pond site, with the above-noted losses and decline in toad breeding success, 40% of B. bufo metamorphs were Bd positive, 46% were Rv positive and 20% were co-infected with both pathogens. Toad metamorphs from a neighbouring water body were also Bd and Rv positive (25 and 55%, respectively). This is the first confirmation of these pathogens in Russia. Questions remain as to the origins of these pathogens in Russia and their roles in documented mass mortality events.
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Final report on effects of environmental radiation of Kori nuclear power plant on human population
International Nuclear Information System (INIS)
Kim, Y.J.; Kim, J.B.; Chung, K.H.; Lee, K.S.; Kim, S.R.; Yang, S.Y.
1980-01-01
In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on the human population, the base line survey for the human monitoring, human life habits, expected individual exposure dose, frequencies of chromosomal aberration, gene frequencies and karyotypes in amphibia, fauna, and radiation sensitivities in microorganisms which have been living around the power plant site were carried out. Kilchonri population which took for the human monitoring lie within a 2 km distance from the power plant site. Human monitoring, house and food characteristics, individual experience of x-ray exposures, human chromosome analysis and fauna were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows: Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana nigromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, Bufo bufo 2N=22. (author)
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Effects of environmental radiation of Kori nuclear power plant on the human population
International Nuclear Information System (INIS)
Kim, Y.J.
1979-01-01
In order to clarify and protect the effects of environmental radiation according to the operation of Kori nuclear power plant on human population, the base line survey for the human monitoring, the fauna of land nocturnal insects, and the karyotypes of amphibian species which have been living around the power plant site were carried out. ''Kilchunri'' population which took for the human monitoring lie within a 2km distance from power plant site. Human monitoring, house and food characteristics, individual experience of X-ray exposures, human chromosome analysis and fauna of nocturnal land insects were surveyed and expressed in numerical tables. Chromosome number obtained from the amphibia which were collected around the power plant area was as follows; Kaloula borealis 2N=30, Rana amurensis 2N=26, Rana dybouskii 2N=24, Rana rugosa 2N=26, Rana migromaculata 2N=26, Rana plancyi 2N=26, Bombina orientalis 2N=24, Hyla arborea 2N=24, Bufo stejnegeri 2N=22, and Bufo bufo 2N=22. (author)
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Directory of Open Access Journals (Sweden)
Durette-Desset M.C.
2000-03-01
Full Text Available A third species of the genus Schulzia Travassos, 1937 a parasite of Leptodactylus rhodonotus (Amphibian, Leptodactylidae originating from Peru is described. By the pattern of the caudal bursa, the specimens are closely related to the two other species. They are distinguished from Schulzia uzu Lent & Santos, 1989, parasite from Atelopus oxyrhynchus in Venezuela, by the shape of the ovejector and from Schulzia travassosi Durette-Desset, Baker & Vaucher, 1985, parasite from Bufo crucifer in Brasil, Bufo granulosus and Leptodactylus bufonius in Paraguay, by the shape of the spicules. The presence of a new species in Peru points out the wide geographic distribution of the genus in the Neotropical region.
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Directory of Open Access Journals (Sweden)
GHERARDI F.
2001-04-01
Full Text Available In the laboratory, the motivation and/or ability to prey on anuran larvae (Bufo bufo, Rana kl. esculenta and R. italica were compared between a native European (Austropotamobius pallipes and an alien North American crayfish species (Procambarus clarkii. Both were skilled predators of tadpoles, adopting a sit-and-wait strategy. However, because P. clarkii displayed lower latency times in the presence of one of the three amphibians (Rana kl. esculenta here tested, the hypothesis is raised that invasive crayfish are more opportunistic predators and possibly faster in switching to different prey than those species they are displacing. From a conservation perspective, these preliminary results further emphasise the importance of studies centred on the invasion-displacement dichotomy.
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Directory of Open Access Journals (Sweden)
Ivelin A. Mollov
2013-12-01
Full Text Available Currently the problem of the effects of the road network and traffic on the amphibians and reptiles in Bulgaria is poorly studied. During the period March 2002 - March 2004 in the Buffer Zone of Biosphere Reserve "Srebarna" (NE Bulgaria were built two anti-fire roads from the eastern and western side of the lake in area of grasslands of semi-steppe type, typical for north-eastern Bulgaria. The aim of the constructed roads is to provide access for fire vehicles to areas in and around the reserve. The current study aims to provide data on the impact of road traffic and the newly constructed road network and another previously existing road on the amphibians and reptiles inhabiting the buffer zone of the biosphere reserve "Srebarna". For the entire period of study in the three studied road sections a total of 15 dead specimens of amphibians belonging to 4 species (Bombina bombina, Hyla arborea, Bufo bufo, Bufo viridis and 70 dead specimens of reptiles belonging to 8 species (Emys orbicularis, Ablepharus kitaibelii, Lacerta viridis, Podarcis tauricus, Podarcis muralis, Natrix natrix, Coronella austriaca and Dolichophis caspius were recorded. Several “hot spots”, where most cadavers were recorded are well described and possible conservation measures are discussed.
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Directory of Open Access Journals (Sweden)
Antonio Romano
2010-12-01
Full Text Available In this study, we present the results of our field and bibliographic survey on the amphibians of the “Cilento and Vallo di Diano” National Park (Southern Italy. Two hundred and thirty three spawning sites (167 original and 66 derived from literature, and 11 amphibian species were found. Reproductive activity was recorded for Salamandra salamandra, Salamandrina terdigitata, Triturus carnifex, Lissotriton italicus, Bufo bufo, Hyla intermedia, Rana italica, Rana dalmatina and Pelophylax synkl. hispanica. The distribution record of many species is widely improved with respect to bibliographic data. Our results also suggested that preservation and restoration of small aquatic sites, in particular of the artificial ones, such as stony wells and drinking-troughs, are fundamental for an appropriate conservation management of amphibians in the “Cilento and Vallo di Diano” National Park.
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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....
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Strategies of water conservation in southern African frogs
African Journals Online (AJOL)
The three approaches which anurans have adopted in response to water ... seen migrating along a path towards the dam, the weather being overcast after light rain .... (1967) has shown that Bufo regularis has an endogenous activity rhythm.
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[Comparison of chemical composition between fresh and processed Bufonis Venenum by UPLC-TQ-MS].
Wang, Zi-yue; Wang, Hong-lan; Zhou, Jing; Ma, Hong-yue; Gong, Yan; Yan, Wen-li; Qian, Da-wei
2015-10-01
Toad venom is the Bufo bufo gargarizans or B. melanostictus after the ears of the gland secretion, used in the treatment of various cancers in recent years. Research shows that the main anti-tumor components in bufadienolide. Bufadienolide have free type structure and conjunct type structure. To identify and clarify the difference between bufogenin and bufotoxin contained in Bufonis Venenum, which was from B. bufo gargarizans, an UPLC-TQ-MS method has been established. UPLC-TQ-MS method was used to identify and quantify the major bufadienolides in Bufonis Venenum. UPLC-TQ-MS assay with positive ion mode was performed on a Waters ACQUITY UPLC BEH C, (2.1 mm x 100 mm, 1.7 µm) with the mobile phase consisting of 0. 1% aqueous formic and acidacetonitrile in gradient elution at a flow rate of 0.4 mL · min⁻¹ and the column temperature was set at 35 °C. By comparing their retention time and high resolution mass data of Bufonis Venenum extracts, 37 effective components were primarily identified by MS/MS analysis in positive ion mode. Twenty-six of them were free-type bufadienolides (bufogenin), 11 of them were conjugated bufadienolides. There were significant differences in the main composition between fresh and processed Bufonis Venenum. The study found that the chemical composition of toad venom through great changes after processing, conjunct type content is much less, free type content as well change.
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Department oJZoology. University oJTexas bufonids Schismaderma ...
African Journals Online (AJOL)
The European and Asian Bu/o faunas appear to be derived primarily from American ... Such data for Eurasian species are principally from. Inger (1972). ...... Effects of temperature, body size, and hybridization on mating calls of toads, Bufo a.
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MARÍA FLORENCIA DANERI; RUBÉN NÉSTOR MUZIO
2015-01-01
En este artículo se describen desde una perspectiva comparativa los fenómenos de bloqueo, ensombrecimiento e inhibición latente, enfatizando su presencia en tareas de aprendizaje espacial. Estos fenómenos de aprendizaje, ampliamente observados en otras clases de vertebrados e invertebrados, han sido recientemente descriptos por primera vez en anfibios, un grupo de vertebrados con un cerebro filogenéticamente antiguo. Tomando como modelo al sapo terrestre Rhinella arenarum, se revisarán los tr...
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2011-11-14
...] Draft Environmental Assessment and Safe Harbor Agreement for the Houston Toad Within Nine Texas Counties... of the endangered Houston toad (Bufo houstonensis) as a result of conservation actions, land...: [email protected] . Include ``Clear Lake Ecological Services Field Office draft Houston Toad...
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Habitat suitability of patch types: A case study of the Yosemite toad
Christina T. Liang; Thomas J. Stohlgren
2011-01-01
Understanding patch variability is crucial in understanding the spatial population structure of wildlife species, especially for rare or threatened species.We used a well-tested maximum entropy species distribution model (Maxent) to map the Yosemite toad (Anaxyrus (= Bufo) canorus) in the Sierra Nevada...
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Bloqueo y ensombrecimiento en un grupo de vertebrados filogenéticamente antiguo: los anfibios
Daneri, M. Florencia; Muzio, Rubén N
2013-01-01
En este artículo se describe el estudio de los fenómenos de bloqueo y ensombrecimiento en una tarea de aprendizaje espacial en un anfibio, el sapo terrestre Rhinella arenarum. Ambos fenómenos de aprendizaje, ampliamente observados en otras clases de vertebrados, se describen por primera vez en un grupo con un cerebro flogenéticamente antiguo, como es el caso de los anfibios. Específicamente, se observó durante el aprendizaje espacial: (1) bloqueo entre claves visuales asociadas a una meta, y ...
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Bloqueo y ensombrecimiento en un grupo de vertebrados filogenéticamente antiguo: los anfibios
M. Florencia Daneri; Rubén N. Muzio
2013-01-01
En este artículo se describe el estudio de los fenómenos de bloqueo y ensombrecimiento en una tarea de aprendizaje espacial en un anfibio, el sapo terrestre Rhinella arenarum. Ambos fenómenos de aprendizaje, ampliamente observados en otras clases de vertebrados, se describen por primera vez en un grupo con un cerebro filogenéticamente antiguo, como es el caso de los anfibios. Específicamente, se observó durante el aprendizaje espacial: (1) bloqueo entre claves visuales asociadas a una meta,...
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Journal of Aquatic Sciences - Vol 20, No 1 (2005)
African Journals Online (AJOL)
Evaluation of acute toxicity of cadmium and lead to amphibian tadpoles (Toad: Bufo maculatus and frog: Ptychadena bibroni) · EMAIL FULL TEXT EMAIL FULL TEXT ... Helminths parasites of Chub mackerel Scomber japonicus (Houttuyn, 1782) from the harbour of Mehdia-Kenitra (Atlantic Coast of Morocco) · EMAIL FULL ...
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1989-08-01
tory of flora. Trees such as Virginia live oak (Quercus virginiana), black willow (Salix nigra), hackberry (Celtislaevi- gata), and persimmon ( Diospyros ...bullfrog, is a human food source today and may have been prehistorically as well. The toad, however, of the genus Bufo is not normally consumed
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Amphibian recovery after a decrease in acidic precipitation.
Dolmen, Dag; Finstad, Anders Gravbrøt; Skei, Jon Kristian
2018-04-01
We here report the first sign of amphibian recovery after a strong decline due to acidic precipitation over many decades and peaking around 1980-90. In 2010, the pH level of ponds and small lakes in two heavily acidified areas in southwestern Scandinavia (Aust-Agder and Østfold in Norway) had risen significantly at an (arithmetic) average of 0.14 since 1988-89. Parallel with the general rise in pH, amphibians (Rana temporaria, R. arvalis, Bufo bufo, Lissotriton vulgaris, and Triturus cristatus) had become significantly more common: the frequency of amphibian localities rose from 33% to 49% (n = 115), and the average number of amphibian species per locality had risen from 0.51 to 0.88. In two other (reference) areas, one with better buffering capacity (Telemark, n = 21) and the other with much less input of acidic precipitation (Nord-Trøndelag, n = 106), there were no significant changes in pH or amphibians.
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DEFF Research Database (Denmark)
Nielsen, Robert; Larsen, Erik Hviid
2007-01-01
(V) with a [Na+] of the transported fluid of 130+/-24 mM ([Na+]Ringer's solution = 117.4 mM). Addition of bumetanide to the inside solution reduced J(V). Water was transported uphill and J(V) reversed at an excess outside osmotic concentration, deltaC(S,rev) = 28.9+/-3.9 mOsm, amiloride decreased delta......C(S,rev) to 7.5+/-1.5 mOsm. It is concluded that water uptake is accomplished by osmotic coupling in the lateral intercellular space (lis), and hypothesized that a small fraction of the Na+ flux pumped into lis is recirculated via basolateral NKCC transporters.......Transepithelial potential (V(T)), conductance (G(T)), and water flow (J(V)) were measured simultaneously with good time resolution (min) in isolated toad (Bufo bufo) skin epithelium with Ringer on both sides. Inside application of 5 microM isoproterenol resulted in the fast increase in G(T) from 1...
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Life Histories of Frogs in the Namib Desert | Channing | African ...
African Journals Online (AJOL)
Four anuran taxa inhabit the central Namib: Xenopus laevis, Tomopterna delalandei cryptotis, Phrynomerus annectens and Bufo vertebrate hoeschi. Xenopus is confined to permanent pools in the Kuiseb river canyon. Tomopterna extends further into the Namib, but is restricted to the Kuiseb river bed. The Kuiseb is normally ...
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Fossil frogs (Anura) from Shanwang (Middle Miocene; Shandong Province, China)
Czech Academy of Sciences Publication Activity Database
Roček, Zbyněk; Dong, L.; Přikryl, Tomáš; Sun, Ch.; Tan, J.; Wang, Y.
2011-01-01
Roč. 44, č. 5 (2011), s. 499-518 ISSN 0016-6995 R&D Projects: GA AV ČR IAA300130705 Institutional research plan: CEZ:AV0Z30130516 Keywords : Anura * Neogene * Bufo * Macropelobates * Rana * Tadpole * East Asia Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.010, year: 2011
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Surveys for California red-legged frog and arroyo toad on the Los Padres National Forest
Valerie K. Hubbartt; Thomas G. Murphey
2005-01-01
Starting in the spring of 1999 through the fall of 2000, USDA Forest Service biologists have conducted surveys throughout the Los Padres National Forest for the federally-listed California red-legged frog (Rana aurora draytonii) and arroyo toad (Bufo californicus). Sites known to have frogs or toads present were monitored for...
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The advertisement call, breeding biology, description of the tadpole ...
African Journals Online (AJOL)
Males of Bufo dombensis were observed calling late at night at Ongongo Waterfall in north-western Namibia. The analyzed advertisement calls differ distinctly from those of B. vertebralis, B. hoeschi and B. fenoulheti, indicating that all these taxa are separate valid species. Tadpoles raised from a breeding pair found at ...
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Nigerian Journal of Physiological Sciences - Vol 31, No 2 (2016)
African Journals Online (AJOL)
Effects of Petrol Exposure on Glucose, Liver and Muscle glycogen levels in the Common African toad Bufo regularis · EMAIL FREE FULL TEXT EMAIL FREE FULL ... Effect of insulin on visuo-spatial memory and histology of cerebral cortex in the presence or absence of nitric oxide inhibition · EMAIL FREE FULL TEXT EMAIL ...
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International Nuclear Information System (INIS)
Macias, Guadalupe; Marco, Adolfo; Blaustein, Andrew R.
2007-01-01
Many aquatic species are sensitive to ambient levels of ultraviolet-B radiation (UVB) and chemical fertilizers. However, recent studies indicate that the interaction among multiple stressors acting simultaneously could be contributing to the population declines of some animal species. Therefore, we tested the potential synergistic effects between ambient levels of UVB and a contaminant, sodium nitrite in the larvae of two amphibian species, the common European toad Bufo bufo and the Iberian green frog Rana perezi. We studied R. perezi from both mountain and coastal populations to examine if populations of the same species varied in their response to stressors in different habitats. Both species were sensitive to the two stressors acting alone, but the interaction between the two stressors caused a multiplicative impact on tadpole survival. For B. bufo, the combination of UVB and nitrite was up to seven times more lethal than mortality for each stressor alone. In a coastal wetland, the combination of UVB and nitrite was four times more toxic for R. perezi than the sum of the effect on mortality for each stressor alone. One mg/L of nitrite killed half the population of R. perezi at Gredos Mountains at day 10 in the absence of UVB. In the presence of UVB, 50% of the tadpoles from the same experiment died at day 7. Similar toxic response were found for R. perezi in two highly contrasted environments suggesting this synergistic interaction can be a widespread phenomenon. The interaction of excess chemical fertilizers and manure with ambient UVB radiation could be contributing to the global decline of some amphibian species. We suggest that potential exposure to UVB radiation be accounted for when assessing water quality criteria regarding nitrite pollution
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Energy Technology Data Exchange (ETDEWEB)
Macias, Guadalupe [Donana Biological Station, CSIC, Spanish Council for Scientific Research. P.O. Box 1056, Sevilla 41013 (Spain); Marco, Adolfo [Donana Biological Station, CSIC, Spanish Council for Scientific Research. P.O. Box 1056, Sevilla 41013 (Spain)], E-mail: amarco@ebd.csic.es; Blaustein, Andrew R. [Department of Zoology, Oregon State University, Corvallis, Oregon, 97331 (United States)
2007-10-15
Many aquatic species are sensitive to ambient levels of ultraviolet-B radiation (UVB) and chemical fertilizers. However, recent studies indicate that the interaction among multiple stressors acting simultaneously could be contributing to the population declines of some animal species. Therefore, we tested the potential synergistic effects between ambient levels of UVB and a contaminant, sodium nitrite in the larvae of two amphibian species, the common European toad Bufo bufo and the Iberian green frog Rana perezi. We studied R. perezi from both mountain and coastal populations to examine if populations of the same species varied in their response to stressors in different habitats. Both species were sensitive to the two stressors acting alone, but the interaction between the two stressors caused a multiplicative impact on tadpole survival. For B. bufo, the combination of UVB and nitrite was up to seven times more lethal than mortality for each stressor alone. In a coastal wetland, the combination of UVB and nitrite was four times more toxic for R. perezi than the sum of the effect on mortality for each stressor alone. One mg/L of nitrite killed half the population of R. perezi at Gredos Mountains at day 10 in the absence of UVB. In the presence of UVB, 50% of the tadpoles from the same experiment died at day 7. Similar toxic response were found for R. perezi in two highly contrasted environments suggesting this synergistic interaction can be a widespread phenomenon. The interaction of excess chemical fertilizers and manure with ambient UVB radiation could be contributing to the global decline of some amphibian species. We suggest that potential exposure to UVB radiation be accounted for when assessing water quality criteria regarding nitrite pollution.
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Observations on the oesophageal glands in some Tanzanian anurans
African Journals Online (AJOL)
in Hyla, Rana, BUfo, Pelobates and Triturus more pep- sinogen was produced in these glands than in the gastric glands. The aim of the present study was to obtain data on the occurrence of oesophageal glands in selected anurans from Tanzania and to compare their structure with the better known gastric glands. Materials ...
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Environmental Assessment: Space Innovation and Development Center Schriever AFB, Colorado
2006-03-01
coloradensis T Greenback cutthroat trout Oncorhynchus clarki stomias T Least tern (interior population) .A Sterna antillarum E Mexican spotted owl Strix...Haliaeetus leucocephalus T Boreal toad Bufo boreas boreas c Canada lynx Lynx canadensis T Greenback cutthroat trout Oncorhynchus clarki stomias T Least...T CUSTER Bald eagle IIaliaeetus leucocephalus T Canada lynx Lynx canadensis T Greenback cutthroat trout Oncorhynchus clarki stomias T Mexican
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The nerve protection and in vivo therapeutic effect of Acalypha indica extract in frogs
Directory of Open Access Journals (Sweden)
Ernie H. Purwaningsih
2010-05-01
Full Text Available Aim To demonstrate nerve protection and/or treatment effect of Acalypha indica Linn. extract on nerve paralysis induced by subcutaneus injection of pancuronium bromide on frog’s back.Methods The study was performed on sixty frogs (Bufo melanostictus Schneider that divided into two groups, i.e. the neuro-protection and neuro-therapy group. Each group was divided further into 6 sub-treatment groups: negative control group treated by water and positive control group treated by piracetam, treatment groups received the extracts 200, 300, 400, 500 mg/kgBW. Pancuronium bromide 0.2% (1 : 20 dilutions were injected subcutaneously as muscle relaxant. The protective effect was studied by giving the extract orally, 1 hour prior to injection; while the therapeutic effect of the extract was studied by 10 minute treatment after injecting pancuronium bromide solution. The parameters measured were the onset and duration of paralysis (in minutes and the recovery time (time needed to recover into normal condition.Results The study showed significantly different protective effect of Acalypha indica Linn. root water extract at 400 and 500 mg/KgBW compared to negative control group and positive control group (piracetam (p < 0.05; while the therapeutic effect was obvious at the dose 200-500 mg/KgBW compared to negative control group (p = 0.000. There was no significant difference compared to positive control group (piracetam, except at 300 mg/KgBW (p = 0.012.Conclusion These results have proven that the water extract of Acalypha indica Linn. root has comparable protective and treatment effect on nerves system, as piracetam, but further studies should be performed to provide more evidences particularly pharmacokinetic and pharmacodynamic studies on two animal models that commonly used. (Med J Indones 2010; 19:96-102Keywords: Acalypha indica Linn, Bufo melanostictus Schneider, nerve-protection
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Directory of Open Access Journals (Sweden)
Bingduo Zhou
2015-01-01
Full Text Available Background. Huachansu, the sterilized water extract of Bufo bufo gargarizans toad skin, is used in China to alleviate the side-effects and enhance the therapeutic effect of chemotherapy in advanced non-small-cell lung cancer (NSCLC. We conducted a meta-analysis to assess Huachansu’s efficacy. Methods. We extensively searched electronic databases (CENTRAL, EMBASE, MEDLINE, CBM, Cochrane Library, CNKI, CEBM, WFDP, CSCD, CSTD, and IPA for randomized controlled trials containing Huachansu plus chemotherapy as the test group and chemotherapy as the control group. Seventeen trials were selected based on the selection criteria. The pooled relative ratio (RR of indicators with 95% confidence interval (95% CI was calculated for efficacy evaluation. Results. The meta-analysis demonstrated a statistically significant improvement in objective tumor response, one-year survival, Karnofsky performance status, pain relief, and alleviation of severe side-effects (nausea and vomiting, leukocytopenia in the test group as compared to the control group, but no significant difference in thrombocytopenia. Conclusions. This study demonstrated the efficacy of Huachansu combined with chemotherapy in the treatment of advanced NSCLC. However, limitations exist and high-quality trials are needed for further verification.
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Phlebotomus Sandflies of the Paloich Area in the Sudan (Diptera, Psychodidae)
1964-10-01
Hamster, Cricetus auratus Toad, Bufo regularis (?) Gecko, H. turicus Skink, M. striata Puff adder Snake, CMNH HH-9111’ Snake, CMNH HH-9112’ Hedgehog ...Pharynx unarmed distally or only with few, smail spines ; pigment patch not dark enough to obscure teeth .................. 8 Pharynx heavily...armed distally with numerous, dark spines ; pigment patch very dark, 1964 Quate: Sudanese sandflies 237 often obscuring teeth unless specimen well
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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...
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Czech Academy of Sciences Publication Activity Database
Hartigan, A.; Fiala, Ivan; Dyková, Iva; Jirků, Miloslav; Okimoto, B.; Rose, K.; Phalen, D. N.; Šlapeta, J.
2011-01-01
Roč. 6, č. 4 (2011), e18871 E-ISSN 1932-6203 R&D Projects: GA AV ČR KJB600960701 Grant - others:GA ČR(CZ) GP204/09/P519 Program:GP Institutional research plan: CEZ:AV0Z60220518 Keywords : EW-SOUTH-WALES * BUFO-MARINUS * BIOLOGICAL INVASIONS * INFECTIOUS-DISEASES * NORTH-AMERICA * TREE FROG * MYXOZOA * SEQUENCES * PHYLOGENY * ECOLOGY Subject RIV: EG - Zoology Impact factor: 4.092, year: 2011
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Zeng, ShaoJu; Li, Jia; Zhang, XinWen; Zuo, MingXue
2007-01-01
The distribution of Met-enkephalin (ENK), substance P (SP) and serotonin (5-HT) differs between the core and shell regions of the mesencephalic and diencephalic auditory nuclei of the turtle [Belekhova et al., 2002]. These neurochemical distinctions are also found in other tetrapods (mammals, birds and amphibians). The distribution of ENK, SP and 5-HT was examined in the core and shell regions of both mesencephalic and diencephalic auditory nuclei, and in the telencephalic auditory areas of Bengalese finches (Lonchura striata) and mice (Mus musculus), as well as in corresponding auditory areas in toads (Bufo bufo). ENK, SP and 5-HT immunoreactive fibers and perikarya were largely absent from the core regions of both mesencephalic and diencephalic auditory nuclei, in comparison with the shell regions of mice and Bengalese finches. In the toad, however, this pattern was observed in the mesencephalic auditory nucleus, but not in the diencephalic auditory areas. ENK and SP immunoreactive perikarya were detected in the telencephalic auditory area of mice, whereas no ENK, SP or 5-HT immunolabeling was observed in the telencephalic auditory area (Field L) of Bengalese finches. These findings are discussed in terms of the evolution of the core-and-shell organization of auditory nuclei of tetrapods. Copyright 2007 S. Karger AG, Basel.
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Digital Repository Service at National Institute of Oceanography (India)
Kumbhar, J; Rivonker, C
konkanensis (Melvill 1893) and Purpura bufo Lamarck 1822 from Goa are described for the first time using SEM photographs. Keywords: Muricidae, Goa, new record, taxonomic diagnosis, radula, SEM. 190 J.V. Kumbhar and C.U. Rivonker / Turk. J. Fish... optical zoom). The specimens were subsequently identified up to species Figure 1. Map of study area indicating sampling sites J.V. Kumbhar and C.U. Rivonker / Turk. J. Fish. Aquat. Sci. 189-197 (2012) 191...
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Byron S. Wilson; Susan E. Koenig; Rick van Veen; Erika Miersma; D. Craig. Rudolph
2011-01-01
The notorious ââcane toadââ (Bufo marinus) is considered to be one of the 100 worst invasive species in the world. A native of South and Central America, Mexico, and the Rio Grande Valley of the United States, this large toad was intentionally introduced to islands in the Caribbean, and subsequently throughout the southern Pacific, as a biological control agent to...
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Lifescience Database Archive (English)
Full Text Available E00121 Toad venom (JP17) Crude drug Hellebrin [CPD:C08868], Resibufogenin [CPD:C17...058], Cinobufagin [CPD:C16931], Bufalin [CPD:C16922], Bufotalin [CPD:C16923], Cinobufotalin [CPD:C16932], Gamabufo...talin [CPD:C16962], Telocinobufagin [CPD:C17072], Hellebrigenin [CPD:C16969], Bufadienolides [CPD:C16921], Cardenolides, Bufo...tenine [CPD:C08299], Bufotenidine [CPD:C13664], Epirenamin...ol, Marinobufagin, Resibufagin, Serotonine, Bufothionine, Dehydrobufotenine, Bufotoxin, Cholesterol [CPD:C00
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... Education & Events Advocacy For Patients About ACOG Induced Abortion Home For Patients Search FAQs Induced Abortion Page ... Induced Abortion FAQ043, May 2015 PDF Format Induced Abortion Special Procedures What is an induced abortion? What ...
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Deriving freshwater quality criteria for 2,4-dichlorophenol for protection of aquatic life in China
International Nuclear Information System (INIS)
Yin Daqiang; Jin Hongjun; Yu Lingwei; Hu Shuangqing
2003-01-01
Criteria were established for an organic pollutant in freshwaters of China. - Freshwater quality criteria for 2,4-dichlorophenol (2,4-DCP) were developed with particular reference to the aquatic biota in China, and based on USEPA's guidelines. Acute toxicity tests were performed on nine different domestic species indigenous to China to determine 48-h LC 50 and 96-h LC 50 values for 2,4-DCP. In addition, 21 day survival-reproduction tests with Daphnia magna, 30-day embryo-larval tests with Carassius auratus, 60 day fry-juvenile test with Ctenopharyngodon idellus, 30 d early life stage tests with Bufo bufo gargarizans and 96 h growth inhibition tests with Scenedesms obliqaus were conducted, to estimate lower chronic limit (LCL) and upper chronic limit (UCL) values. The final acute value (FAV) was 2.49 mg/l 2,4-DCP. Acute-to-chronic ratios (ACR) ranged from 3.74 to 22.5. The final chronic value (FCV) and the final plant value (FPV) of 2.4-DCP were 0.212 mg/l and 7.07 mg/l respectively. Based on FAV, FCV, and FPV, a criteria maximum concentration (CMC) of 1.25 mg/l and a criterion continuous concentration (CCC) of 0.212 mg/l were derived. The results of this study provide useful data for deriving national or local water quality criteria for 2,4-DCP based on aquatic biota in China
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Hallucinogenic drugs in pre-Columbian Mesoamerican cultures.
Carod-Artal, F J
2015-01-01
The American continent is very rich in psychoactive plants and fungi, and many pre-Columbian Mesoamerican cultures used them for magical, therapeutic and religious purposes. The archaeological, ethno-historical and ethnographic evidence of the use of hallucinogenic substances in Mesoamerica is reviewed. Hallucinogenic cactus, plants and mushrooms were used to induce altered states of consciousness in healing rituals and religious ceremonies. The Maya drank balché (a mixture of honey and extracts of Lonchocarpus) in group ceremonies to achieve intoxication. Ritual enemas and other psychoactive substances were also used to induce states of trance. Olmec, Zapotec, Maya and Aztec used peyote, hallucinogenic mushrooms (teonanacatl: Psilocybe spp) and the seeds of ololiuhqui (Turbina corymbosa), that contain mescaline, psilocybin and lysergic acid amide, respectively. The skin of the toad Bufo spp contains bufotoxins with hallucinogenic properties, and was used since the Olmec period. Jimson weed (Datura stramonium), wild tobacco (Nicotiana rustica), water lily (Nymphaea ampla) and Salvia divinorum were used for their psychoactive effects. Mushroom stones dating from 3000 BC have been found in ritual contexts in Mesoamerica. Archaeological evidence of peyote use dates back to over 5000 years. Several chroniclers, mainly Fray Bernardino de Sahagún, described their effects in the sixteenth century. The use of psychoactive substances was common in pre-Columbian Mesoamerican societies. Today, local shamans and healers still use them in ritual ceremonies in Mesoamerica. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.
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Keranen, Katie M.; Weingarten, Matthew
2018-05-01
The ability of fluid-generated subsurface stress changes to trigger earthquakes has long been recognized. However, the dramatic rise in the rate of human-induced earthquakes in the past decade has created abundant opportunities to study induced earthquakes and triggering processes. This review briefly summarizes early studies but focuses on results from induced earthquakes during the past 10 years related to fluid injection in petroleum fields. Study of these earthquakes has resulted in insights into physical processes and has identified knowledge gaps and future research directions. Induced earthquakes are challenging to identify using seismological methods, and faults and reefs strongly modulate spatial and temporal patterns of induced seismicity. However, the similarity of induced and natural seismicity provides an effective tool for studying earthquake processes. With continuing development of energy resources, increased interest in carbon sequestration, and construction of large dams, induced seismicity will continue to pose a hazard in coming years.
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International Nuclear Information System (INIS)
Ahmad, M.; Haider, N.; Siddiqui, R.Q.R.
1980-01-01
This study deals with the effects of vitamin A and dexamethasone (DXM) on the metamorphosis of irradiated tadpoles. Results indicate that hypervitaminosis A depresses the metamorphosing action of thyroxine for several days. On the contrary, dexamethasone accelerates the action of exogenous thyroxine on tadpoles. Thus present data suggest that DXM supresses STH synthesis and promotes TSH secretion. Moreover, muscle appears to be its target tissue and DXM seems to promote the proteolytic digestion of the larval tail. (author)
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Deriving freshwater quality criteria for 2,4-dichlorophenol for protection of aquatic life in China
Energy Technology Data Exchange (ETDEWEB)
Yin Daqiang; Jin Hongjun; Yu Lingwei; Hu Shuangqing
2003-04-01
Criteria were established for an organic pollutant in freshwaters of China. - Freshwater quality criteria for 2,4-dichlorophenol (2,4-DCP) were developed with particular reference to the aquatic biota in China, and based on USEPA's guidelines. Acute toxicity tests were performed on nine different domestic species indigenous to China to determine 48-h LC{sub 50} and 96-h LC{sub 50} values for 2,4-DCP. In addition, 21 day survival-reproduction tests with Daphnia magna, 30-day embryo-larval tests with Carassius auratus, 60 day fry-juvenile test with Ctenopharyngodon idellus, 30 d early life stage tests with Bufo bufo gargarizans and 96 h growth inhibition tests with Scenedesms obliqaus were conducted, to estimate lower chronic limit (LCL) and upper chronic limit (UCL) values. The final acute value (FAV) was 2.49 mg/l 2,4-DCP. Acute-to-chronic ratios (ACR) ranged from 3.74 to 22.5. The final chronic value (FCV) and the final plant value (FPV) of 2.4-DCP were 0.212 mg/l and 7.07 mg/l respectively. Based on FAV, FCV, and FPV, a criteria maximum concentration (CMC) of 1.25 mg/l and a criterion continuous concentration (CCC) of 0.212 mg/l were derived. The results of this study provide useful data for deriving national or local water quality criteria for 2,4-DCP based on aquatic biota in China.
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(Ciliophora: Peritrichia) from the urinary bladder of Bufo gutturalis
African Journals Online (AJOL)
1988-09-07
Sep 7, 1988 ... vesicola Suzuki, 1950 from Rana rugosa (Suzuki 1950). The question arises whether T. dampanula sp. n. may possibly be the same species as observed by Fantham. (1924) in the urinary bladder of B. regularis, i.e. T. bufonis. Owing to the fact that none of the character- istics provided by Fantham (1924) ...
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Electrophoretic pattern of blood serum proteins of some of the vertebrates of Pakistan
International Nuclear Information System (INIS)
Shakoori, Abdul Rauf; Zaheer, Saleem Akhtar; Ahmad, Muhammad Salih.
1976-01-01
The electrophoretic pattern of blood serum proteins of some of the common fishes e.g. Catla catla, Cirrhina mrigala, Channa punctatus, Channa marulius, Wallago attu, Heterop-neustes fossilis; amphibia e.g., Rana tigrina, Rana cyanophlyctis, Bufo melanostictus; reptiles e.g. Varanus bengalensis, Uromastix hardwickii; birds e.g. Columba livia, Gallus domesticus, Passer domestica, Anas platyrhynchos; and mammals e.g. Homo sapiens, Mus musculus, Lepus cuniculus have been described. The mobility of proteins of blood sera has been studied over cellulose acetate paper and then a comparative pattern analysed
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NHE-1 sequence and expression in toad, snake and fish red blood cells
DEFF Research Database (Denmark)
Thomsen, Steffen Nyegaard; Wang, Tobias; Kristensen, Torsten
Red blood cells (RBC) from reptiles appear not to express regulatory volume increase (RVI) upon shrinkage (Kristensen et al., 2008). In other vertebrates, the RVI response is primarily mediated by activation of the Na+/H+ exchanger (NHE-1) and we, therefore decided to investigate whether red cells...... of reptiles express a different NHE-1 that responds less to volume activation compared to other vertebrates or simply lack the Na+/H+ exchanger. Using various tissues from the ball python (Python regius), Cane toad (Bufo marinus) and European perch (Perca fluviatilis), cDNA libraries were created...
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Reynolds, R.P.; Foster, M.S.
1992-01-01
We report on a collection of 74 frogs, 11 lots of frog eggs or tadpoles, and two snakes collected from the Chapare Region in the yungas of the eastern Andean Cordillera de Cochabamba, Bolivia. Collecting localities range from approximately 300 m to >3200 m in elevation. The specimens pertain to 23 species, probably 10 of which are undescribed. We describe four new species of frogs, one each in the genera Bufo, Centrolenella, Colostethus, and Hyla, and one new species of snake, genus Dipsas. We place Atelopus rugulosus in synonymy with A. tricolor.
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... Videos for Educators Search English Español Exercise-Induced Asthma KidsHealth / For Parents / Exercise-Induced Asthma What's in ... Exercise-Induced Asthma Print What Is Exercise-Induced Asthma? Most kids and teens with asthma have symptoms ...
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Directory of Open Access Journals (Sweden)
Westerterp KR
2004-08-01
Full Text Available Objective Daily energy expenditure consists of three components: basal metabolic rate, diet-induced thermogenesis and the energy cost of physical activity. Here, data on diet-induced thermogenesis are reviewed in relation to measuring conditions and characteristics of the diet. Methods Measuring conditions include nutritional status of the subject, physical activity and duration of the observation. Diet characteristics are energy content and macronutrient composition. Results Most studies measure diet-induced thermogenesis as the increase in energy expenditure above basal metabolic rate. Generally, the hierarchy in macronutrient oxidation in the postprandial state is reflected similarly in diet-induced thermogenesis, with the sequence alcohol, protein, carbohydrate, and fat. A mixed diet consumed at energy balance results in a diet induced energy expenditure of 5 to 15 % of daily energy expenditure. Values are higher at a relatively high protein and alcohol consumption and lower at a high fat consumption. Protein induced thermogenesis has an important effect on satiety. In conclusion, the main determinants of diet-induced thermogenesis are the energy content and the protein- and alcohol fraction of the diet. Protein plays a key role in body weight regulation through satiety related to diet-induced thermogenesis.
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DEFF Research Database (Denmark)
Møbjerg, Nadja; Larsen, Erik Hviid; Novak, Ivana
2002-01-01
V, respectively (N=11; 11). This conductance could also be inhibited by Ba(2+), which depolarized a V(bl) of -71+/-5 mV by 9+/-3 mV (N=5). The pump inhibitor ouabain (1 mmol l(-1)) depolarized V(bl), but addition of furosemide to bath solution did not affect V(bl). The [K(+)] in urine varied from 1.3 to 22.8 mmol...
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Malysheva, M N
2014-01-01
The data on the fauna of trypanosomes of Anura of the Leningrad Province are given. The initial development stages of Trypanosoma rotatorium in peripheral blood and internal organs of the frog are described for the first time.
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Villa, Andrea; Blain, Hugues-Alexandre; van den Hoek Ostende, Lars W.; Delfino, Massimo
2018-05-01
Few Quaternary herpetofaunas have been recovered from The Netherlands. Among these, the one coming from the early Pleistocene site of the Russel-Tiglia-Egypte pit near Tegelen is of particular interest, because it is the type locality of the recently described, last western European palaeobatrachid anuran, Palaeobatrachus eurydices. The large number of fossil remains of amphibians and reptiles found in the pit are representative of a very diverse fauna, including at least 17 taxa: Triturus gr. T. cristatus, Lissotriton sp., Pelobates fuscus, Bufo bufo, Bombina sp., Pelophylax sp., Rana sp., Hyla gr. H. arborea, Pelodytes sp., Mauremys sp., Lacerta sp., Lacertidae indet., Anguis gr. A. fragilis, cf. Pseudopus sp., "colubrines" indet., Natrix natrix and Vipera sp. Emys orbicularis, previously reported from a different Tegelen pit, is not present in this assemblage. Palaeoclimatic conditions reconstructed based on the herpetofaunistic association indicate a humid subtropical climate (Cfa according to the Köppen-Geiger classification of climates) for Tegelen during the TC5 section of the Tiglian, with low, but fairly regular rainfalls during the year. Mean annual temperature was 13.4 ± 0.3 °C and mean annual precipitation was 542 ± 50 mm. Moreover, three dry months were present during summer and early autumn, resulting in a much drier climate than the one present at Tegelen today. Nevertheless, the occurrence of the water-dwelling P. eurydices suggests the persistence of suitable permanent water bodies during the whole year, and the survival of this taxon in this part of Europe might have been allowed by the generally humid climate.
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Directory of Open Access Journals (Sweden)
Rosie D Salazar
Full Text Available The common toad (Bufo bufo is of increasing conservation concern in the United Kingdom (UK due to dramatic population declines occurring in the past century. Many of these population declines coincided with reductions in both terrestrial and aquatic habitat availability and quality and have been primarily attributed to the effect of agricultural land conversion (of natural and semi-natural habitats to arable and pasture fields and pond drainage. However, there is little evidence available to link habitat availability with common toad population declines, especially when examined at a broad landscape scale. Assessing such patterns of population declines at the landscape scale, for instance, require an understanding of how this species uses terrestrial habitat.We intensively studied the terrestrial resource selection of a large population of common toads in Oxfordshire, England, UK. Adult common toads were fitted with passive integrated transponder (PIT tags to allow detection in the terrestrial environment using a portable PIT antenna once toads left the pond and before going into hibernation (April/May-October 2012 and 2013. We developed a population-level resource selection function (RSF to assess the relative probability of toad occurrence in the terrestrial environment by collecting location data for 90 recaptured toads.The predicted relative probability of toad occurrence for this population was greatest in wooded habitat near to water bodies; relative probability of occurrence declined dramatically > 50 m from these habitats. Toads also tended to select habitat near to their breeding pond and toad occurrence was negatively related to urban environments.
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Effects of amphibian chytrid fungus on individual survival probability in wild boreal toads
Pilliod, D.S.; Muths, E.; Scherer, R. D.; Bartelt, P.E.; Corn, P.S.; Hossack, B.R.; Lambert, B.A.; Mccaffery, R.; Gaughan, C.
2010-01-01
Chytridiomycosis is linked to the worldwide decline of amphibians, yet little is known about the demographic effects of the disease. We collected capture-recapture data on three populations of boreal toads (Bufo boreas [Bufo = Anaxyrus]) in the Rocky Mountains (U.S.A.). Two of the populations were infected with chytridiomycosis and one was not. We examined the effect of the presence of amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]; the agent of chytridiomycosis) on survival probability and population growth rate. Toads that were infected with Bd had lower average annual survival probability than uninfected individuals at sites where Bd was detected, which suggests chytridiomycosis may reduce survival by 31-42% in wild boreal toads. Toads that were negative for Bd at infected sites had survival probabilities comparable to toads at the uninfected site. Evidence that environmental covariates (particularly cold temperatures during the breeding season) influenced toad survival was weak. The number of individuals in diseased populations declined by 5-7%/year over the 6 years of the study, whereas the uninfected population had comparatively stable population growth. Our data suggest that the presence of Bd in these toad populations is not causing rapid population declines. Rather, chytridiomycosis appears to be functioning as a low-level, chronic disease whereby some infected individuals survive but the overall population effects are still negative. Our results show that some amphibian populations may be coexisting with Bd and highlight the importance of quantitative assessments of survival in diseased animal populations. Journal compilation. ?? 2010 Society for Conservation Biology. No claim to original US government works.
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Exercise-Induced Bronchoconstriction (EIB)
... Conditions & Treatments ▸ Conditions Dictionary ▸ Exercise-Induced Bronchoconstriction Share | Exercise-Induced Bronchoconstriction (EIB) « Back to A to Z Listing Exercise-Induced Bronchoconstriction, (EIB), often known as exercise-induced ...
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Induced pluripotency with endogenous and inducible genes
International Nuclear Information System (INIS)
Duinsbergen, Dirk; Eriksson, Malin; Hoen, Peter A.C. 't; Frisen, Jonas; Mikkers, Harald
2008-01-01
The recent discovery that two partly overlapping sets of four genes induce nuclear reprogramming of mouse and even human cells has opened up new possibilities for cell replacement therapies. Although the combination of genes that induce pluripotency differs to some extent, Oct4 and Sox2 appear to be a prerequisite. The introduction of four genes, several of which been linked with cancer, using retroviral approaches is however unlikely to be suitable for future clinical applications. Towards developing a safer reprogramming protocol, we investigated whether cell types that express one of the most critical reprogramming genes endogenously are predisposed to reprogramming. We show here that three of the original four pluripotency transcription factors (Oct4, Klf4 and c-Myc or MYCER TAM ) induced reprogramming of mouse neural stem (NS) cells exploiting endogenous SoxB1 protein levels in these cells. The reprogrammed neural stem cells differentiated into cells of each germ layer in vitro and in vivo, and contributed to mouse development in vivo. Thus a combinatorial approach taking advantage of endogenously expressed genes and inducible transgenes may contribute to the development of improved reprogramming protocols
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Directory of Open Access Journals (Sweden)
Yu-Chun Wang
2013-11-01
Full Text Available Background/Aims: Copper is an essential trace element for normal cellular function and contributes to critical physiological or pathological processes. The aim of the study was to investigate the effects of copper on vascular tone of rat mesenteric artery and compare the effects of copper on noradrenaline (NA and high K+ induced vasoconstriction. Methods: The rat mesenteric arteries were isolated and the vessel tone was measured by using multi wire myograph system in vitro. Blood pressure of carotid artery in rabbits was measured by using physiological data acquisition and analysis system in vivo. Results: Copper dose-dependently blunted NA-induced vasoconstriction of rat mesenteric artery. Copper-induced vasorelaxation was inhibited when the vessels were pretreated with NG-nitro-L-arginine methyl ester (L-NAME. Copper did not blunt high K+-induced vasoconstriction. Copper preincubation inhibited NA-evoked vasoconstriction and the inhibition was not affected by the presence of L-NAME. Copper preincubation showed no effect on high K+-evoked vasoconstriction. Copper chelator diethyldithiocarbamate trihydrate (DTC antagonized the vasoactivity induced by copper in rat mesenteric artery. In vivo experiments showed that copper injection (iv significantly decreased blood pressure of rabbits and NA or DTC injection (iv did not rescue the copper-induced hypotension and animal death. Conclusion: Copper blunted NA but not high K+-induced vasoconstriction of rat mesenteric artery. The acute effect of copper on NA-induced vasoconstriction was depended on nitric oxide (NO, but the effect of copper pretreatment on NA-induced vasoconstriction was independed on NO, suggesting that copper affected NA-induced vasoconstriction by two distinct mechanisms.
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Hakim, J; Gipouloux, J D
1975-10-27
At early neurula stage of the toad, cranio-caudal and dorso-ventral reversal of lateral mesoblast is performed. The genito-urinary system is therefore missing after this intervention. The three following factors of the formation of this system anlage are anlyzed: lateral mesoderm competence, stimulative activites of dorso-caudal endoblast on the one hand, of chordo-mesoderm on the other hand.
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DEFF Research Database (Denmark)
Budtz, Poul Egede; Christoffersen, Betina C.; Johansen, Jesper S.
1995-01-01
Mitochondria-rich cells (MRC) of the amphibian epidermis are responsible for active chloride uptake at low external salinity, and new MRCs are recruited in response to exposure to distilled (deionized) water. The time-course of this recruitment, the tissue kinetics and ion transport have been...
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Enhanced stimulus-induced gamma activity in humans during propofol-induced sedation.
Directory of Open Access Journals (Sweden)
Neeraj Saxena
Full Text Available Stimulus-induced gamma oscillations in the 30-80 Hz range have been implicated in a wide number of functions including visual processing, memory and attention. While occipital gamma-band oscillations can be pharmacologically modified in animal preparations, pharmacological modulation of stimulus-induced visual gamma oscillations has yet to be demonstrated in non-invasive human recordings. Here, in fifteen healthy humans volunteers, we probed the effects of the GABAA agonist and sedative propofol on stimulus-related gamma activity recorded with magnetoencephalography, using a simple visual grating stimulus designed to elicit gamma oscillations in the primary visual cortex. During propofol sedation as compared to the normal awake state, a significant 60% increase in stimulus-induced gamma amplitude was seen together with a 94% enhancement of stimulus-induced alpha suppression and a simultaneous reduction in the amplitude of the pattern-onset evoked response. These data demonstrate, that propofol-induced sedation is accompanied by increased stimulus-induced gamma activity providing a potential window into mechanisms of gamma-oscillation generation in humans.
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International Nuclear Information System (INIS)
Green, W.R.
1979-01-01
This dissertation discusses some of the new ways that lasers can be used to control the energy flow in a medium. Experimental and theoretical considerations of the laser-induced collision are discussed. The laser-induced collision is a process in which a laser is used to selectively transfer energy from a state in one atomic or molecular species to another state in a different species. The first experimental demonstration of this process is described, along with later experiments in which lasers were used to create collisional cross sections as large as 10 - 13 cm 2 . Laser-induced collisions utilizing both a dipole-dipole interaction and dipole-quadrupole interaction have been experimentally demonstrated. The theoretical aspects of other related processes such as laser-induced spin-exchange, collision induced Raman emission, and laser-induced charge transfer are discussed. Experimental systems that could be used to demonstrate these various processes are presented. An experiment which produced an inversion of the resonance line of an ion by optical pumping of the neutral atom is described. This type of scheme has been proposed as a possible method for constructing VUV and x-ray lasers
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Diet-induced obesity attenuates fasting-induced hyperphagia.
Briggs, D I; Lemus, M B; Kua, E; Andrews, Z B
2011-07-01
Obesity impairs arcuate (ARC) neuropeptide Y (NPY)/agouti-releated peptide (AgRP) neuronal function and renders these homeostatic neurones unresponsive to the orexigenic hormone ghrelin. In the present study, we investigated the effect of diet-induced obesity (DIO) on feeding behaviour, ARC neuronal activation and mRNA expression following another orexigenic stimulus, an overnight fast. We show that 9 weeks of high-fat feeding attenuates fasting-induced hyperphagia by suppressing ARC neuronal activation and hypothalamic NPY/AgRP mRNA expression. Thus, the lack of appropriate feeding responses in DIO mice to a fast is caused by failure ARC neurones to recognise and/or respond to orexigenic cues. We propose that fasting-induced hyperphagia is regulated not by homeostatic control of appetite in DIO mice, but rather by changes in the reward circuitry. © 2011 The Authors. Journal of Neuroendocrinology © 2011 Blackwell Publishing Ltd.
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Tran, Dinh Thi Minh; Phan, Trang Thi Phuong; Huynh, Thanh Kieu; Dang, Ngan Thi Kim; Huynh, Phuong Thi Kim; Nguyen, Tri Minh; Truong, Tuom Thi Tinh; Tran, Thuoc Linh; Schumann, Wolfgang; Nguyen, Hoang Duc
2017-07-25
Besides Escherichia coli, Bacillus subtilis is an important bacterial species for the production of recombinant proteins. Recombinant genes are inserted into shuttle expression vectors which replicate in both E. coli and in B. subtilis. The ligation products are first transformed into E. coli cells, analyzed for correct insertions, and the correct recombinant plasmids are then transformed into B. subtilis. A major problem using E. coli cells can be the strong basal level of expression of the recombinant protein which may interfere with the stability of the cells. To minimize this problem, we developed strong expression vectors being repressed in E. coli and inducer-free in B. subtilis. In general, induction of IPTG-inducible expression vectors is determined by the regulatory lacI gene encoding the LacI repressor in combination with the lacO operator on the promoter. To investigate the inducer-free properties of the vectors, we constructed inducer-free expression plasmids by removing the lacI gene and characterized their properties. First, we examined the ability to repress a reporter gene in E. coli, which is a prominent property facilitating the construction of the expression vectors carrying a target gene. The β-galactosidase (bgaB gene) basal levels expressed from Pgrac01-bgaB could be repressed at least twice in the E. coli cloning strain. Second, the inducer-free production of BgaB from four different plasmids with the Pgrac01 promoter in B. subtilis was investigated. As expected, BgaB expression levels of inducer-free constructs are at least 37 times higher than that of the inducible constructs in the absence of IPTG, and comparable to those in the presence of the inducer. Third, using efficient IPTG-inducible expression vectors containing the strong promoter Pgrac100, we could convert them into inducer-free expression plasmids. The BgaB production levels from the inducer-free plasmid in the absence of the inducer were at least 4.5 times higher than that of
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Vignoli, Leonardo; Bologna, Marco A.; Luiselli, Luca
2007-03-01
We studied community structure and seasonal activity patterns in a system of four ponds with seasonally-variable hydrology at a Mediterranean area in central Italy. We used a set of field methods to assess species presence and relative frequency of observation. The network of ponds was inhabited by six species of amphibians, two salamanders and four frogs. The breeding phenology of the six species did not vary remarkably among ponds, but there were significant differences among species in use of ponds. Factorial analysis of pond similarity drawn from percentage composition of the amphibian fauna, revealed that each of the four ponds was treatable as independent units, with no influence of relative inter-pond distance. PCA analysis allowed us to spatially arrange the amphibian species into three main groups: two were monospecific groups (i.e., Triturus vulgaris and Bufo bufo) and the third consisted of those species that selected not only the largest-deepest ponds, but also the ephemeral ones (i.e., Triturus carnifex, Hyla intermedia, the green frogs and Rana dalmatina). Our results suggest that the inter-pond differences in riparian vegetation, water depth, aquatic vegetation structure/abundance, and soil composition may produce differences among pond ecological characteristics (i.e., water turbidity and temperature, shelter availability, abundance of oviposition micro-sites), which may in turn influence different patterns of use by amphibians. To our knowledge, this is the first study emphasizing the potential role of heterochrony in the maintenance of a high species richness in Mediterranean amphibian communities. Preservation of freshwater vertebrate biodiversity requires management and protection not only of the main ponds and water bodies but also the temporary and ephemeral shallow ponds.
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Uterine contraction induced by Tanzanian plants used to induce abortion
DEFF Research Database (Denmark)
Nikolajsen, Tine; Nielsen, Frank; Rasch, Vibeke
2011-01-01
Women in Tanzania use plants to induce abortion. It is not known whether the plants have an effect.......Women in Tanzania use plants to induce abortion. It is not known whether the plants have an effect....
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Protective immunity to UV radiation-induced skin tumours induced by skin grafts and epidermal cells
International Nuclear Information System (INIS)
Ronald Sluyter; Kylie S Yuen; Gary M Halliday
2001-01-01
There is little evidence that cutaneous dendritic cells (DC), including epidermal Langerhans cells (LC), can induce immunity to UV radiation (UVR)-induced skin tumours. Here, it is shown that cells within skin can induce protective antitumour immunity against a UVR-induced fibrosarcoma. Transplantation of the skin overlying subcutaneous tumours onto naive recipients could induce protective antitumour immunity, probably because the grafting stimulated the tumour Ag-loaded DC to migrate to local lymph nodes. This suggests that cutaneous APC can present tumour Ag to induce protective antitumour immunity. Previously, it has been shown that immunization of mice with MHC class II+ epidermal cells (EC) pulsed with tumour extracts could induce delayed-type hypersensitivity against tumour cells. Here, this same immunization protocol could induce protective immunity against a minimum tumorigenic dose of UVR-induced fibrosarcoma cells, but not higher doses. Epidermal cells obtained from semiallogeneic donors and pulsed with tumour extract could also induce protective immunity. However, presentation of BSA Ag from the culture medium was found to contribute to this result using semiallogeneic EC. The results suggest that LC overlying skin tumours may be able to induce protective immunity to UVR-induced tumours if stimulated to migrate from the skin. Copyright (2001) Australasian Society of Immunology Inc
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International Nuclear Information System (INIS)
Ohyama, Harumi
1995-01-01
Apoptosis is an active process of gene-directed cellular self-destruction that can be induced in many cell types via numerous physiological and pathological stimuli. We found that interphasedeath of thymocytes is a typical apoptosis showing the characteristic features of apoptosis including cell shrinkage, chromatin condensation and DNA degradation. Moderate dose of radiation induces extensive apoptosis in rapidly proliferating cell population such as the epithelium of intestinal crypt. Recent reports indicate that the ultimate form of radiation-induced mitotic death in several cells is also apoptosis. One of the hallmarks of apoptosis is the enzymatic internucleosomal degradation of chromatin DNA. We identified an endonuclease responsible for the radiation-induced DNA degradation in rat thymocytes. The death-sparing effects of interrupting RNA and protein synthesis suggested a cell genetic program for apoptosis. Apoptosis of thymocytes initiated by DNA damage, such as radiation and radio mimetic substance, absolutely requires the protein of p53 cancer suppresser gene. The cell death induced by glucocorticoid, or aging, has no such requirement. Expression of oncogene bcl-2 rescues cells from the apoptosis. Massive apoptosis in radiosensitive cells induced by higher dose radiation may be fatal. It is suggested that selective apoptotic elimination of cells would play an important role for protection against carcinogenesis and malformation through removal of cells with unrepaired radiation-induced DNA damages. Data to evaluate the significance of apoptosis in the radiation risk are still poor. Further research should be done in order to clarify the roles of the cell death on the acute and late effects of irradiation. (author)
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Trauma-induced systemic inflammatory response versus exercise-induced immunomodulatory effects.
Fehrenbach, Elvira; Schneider, Marion E
2006-01-01
Accidental trauma and heavy endurance exercise, both induce a kind of systemic inflammatory response, also called systemic inflammatory response syndrome (SIRS). Exercise-related SIRS is conditioned by hyperthermia and concomitant heat shock responses, whereas trauma-induced SIRS manifests concomitantly with tissue necrosis and immune activation, secondarily followed by fever. Inflammatory cytokines are common denominators in both trauma and exercise, although there are marked quantitative differences. Different anti-inflammatory cytokines may be involved in the control of inflammation in trauma- and exercise-induced stress. Exercise leads to a balanced equilibrium between inflammatory and anti-inflammatory responses. Intermittent states of rest, as well as anti-oxidant capacity, are lacking or minor in trauma but are high in exercising individuals. Regular training may enhance immune competence, whereas trauma-induced SIRS often paves the way for infectious complications, such as sepsis.
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Shock-induced electrical activity in polymeric solids. A mechanically induced bond scission model
International Nuclear Information System (INIS)
Graham, R.A.
1979-01-01
When polymeric solids are subjected to high-pressure shock loading, two anomalous electrical phenomena, shock-induced conduction and shock-induced polarization, are observed. The present paper proposes a model of mechanically induced bond scission within the shock front to account for the effects. An experimental study of shock-induced polarization in poly(pyromellitimide) (Vespel SP-1) is reported for shock compressions from 17 to 23% (pressures from 2.5 to 5.4 GPa). Poly(pyromellitimide) is found to be a strong generator of such polarization and the polarization is found to reflect an irreversible or highly hysteretic process. The present measurements are combined with prior measurements to establish a correlation between monomer structure and strength of shock-induced polarization; feeble signals are observed in the simpler monomer repeat units of poly(tetrafluoroethylene) and polyethylene while the strongest signals are observed in more complex monomers of poly(methyl methacrylate) and poly(pyromellitimide). It is also noted that there is an apparent correlation between shock-induced conduction and shock-induced polarization. Such shock-induced electrical activity is also found to be well correlated with the propensity for mechanical bond scission observed in experiments carried out in conventional mechanochemical studies. The bond scission model can account for characteristics observed for electrical activity in shock-loaded polymers and their correlation to monomer structure. Localization of elastic energy within the monomer repeat unit or along the main chain leads to the different propensities for bond scission and resulting shock-induced electrical activity
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Muzaffar, Suhail; Chattoo, Bharat B
2017-03-01
Anacardic acid is a medicinal phytochemical that inhibits proliferation of fungal as well as several types of cancer cells. It induces apoptotic cell death in various cell types, but very little is known about the mechanism involved in the process. Here, we used budding yeast Saccharomyces cerevisiae as a model to study the involvement of some key elements of apoptosis in the anacardic acid-induced cell death. Plasma membrane constriction, chromatin condensation, DNA degradation, and externalization of phosphatidylserine (PS) indicated that anacardic acid induces apoptotic cell death in S. cerevisiae. However, the exogenous addition of broad-spectrum caspase inhibitor Z-VAD-FMK or deletion of the yeast caspase Yca1 showed that the anacardic acid-induced cell death is caspase independent. Apoptosis-inducing factor (AIF1) deletion mutant was resistant to the anacardic acid-induced cell death, suggesting a key role of Aif1. Overexpression of Aif1 made cells highly susceptible to anacardic acid, further confirming that Aif1 mediates anacardic acid-induced apoptosis. Interestingly, instead of the increase in the intracellular reactive oxygen species (ROS) normally observed during apoptosis, anacardic acid caused a decrease in the intracellular ROS levels. Quantitative real-time PCR analysis showed downregulation of the BIR1 survivin mRNA expression during the anacardic acid-induced apoptosis.
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International Nuclear Information System (INIS)
Rohwetter, Ph.; Stelmaszczyk, K.; Woeste, L.; Ackermann, R.; Mejean, G.; Salmon, E.; Kasparian, J.; Yu, J.; Wolf, J.-P.
2005-01-01
We demonstrate laser induced ablation and plasma line emission from a metallic target at distances up to 180 m from the laser, using filaments (self-guided propagation structures ∼ 100 μm in diameter and ∼ 5 x 10 13 W/cm 2 in intensity) appearing as femtosecond and terawatt laser pulses propagating in air. The remarkable property of filaments to propagate over a long distance independently of the diffraction limit opens the frontier to long range operation of the laser-induced breakdown spectroscopy technique. We call this special configuration of remote laser-induced breakdown spectroscopy 'remote filament-induced breakdown spectroscopy'. Our results show main features of filament-induced ablation on the surface of a metallic sample and associated plasma emission. Our experimental data allow us to estimate requirements for the detection system needed for kilometer-range remote filament-induced breakdown spectroscopy experiment
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Harris, John E.
2016-01-01
Synopsis Chemical-induced depigmentation of the skin has been recognized for over 75 years, first as an occupational hazard but then extending to those using household commercial products as common as hair dyes. Since their discovery, these chemicals have been used therapeutically in patients with severe vitiligo to depigment their remaining skin and improve their appearance. The importance of recognizing this phenomenon was highlighted during an outbreak of vitiligo in Japan during the summer of 2013, when over 16,000 users of a new skin lightening cosmetic cream developed skin depigmentation at the site of contact with the cream and many in remote areas as well. Depigmenting chemicals appear to be analogs of the amino acid tyrosine that disrupt melanogenesis and result in autoimmunity and melanocyte destruction. Because chemical-induced depigmentation is clinically and histologically indistinguishable from non-chemically induced vitiligo, and because these chemicals appear to induce melanocyte autoimmunity, this phenomenon should be known as “chemical-induced vitiligo”, rather than less accurate terms that have been previously used. PMID:28317525
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Pump, sodium, inducer, intermediate size (ISIP) (impeller/inducer/diffuser retrofit)
International Nuclear Information System (INIS)
Paradise, D.R.
1978-01-01
This specification defines the requirements for the Intermediate-Size Inducer Pump (ISIP), which is to be made by replacing the impeller of the FFTF Prototype Pump with a new inducer, impeller, diffuser, seal, and necessary adapter hardware. Subsequent testing requirements of the complete pump assembly are included
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Flow-induced and acoustically induced vibration experience in operating gas-cooled reactors
International Nuclear Information System (INIS)
Halvers, L.J.
1977-03-01
An overview has been presented of flow-induced and acoustically induced vibration failures that occurred in the past in gas-cooled graphite-moderated reactors, and the importance of this experience for the Gas-Cooled Fast-Breeder Reactor (GCFR) project has been assessed. Until now only failures in CO 2 -cooled reactors have been found. No problems with helium-cooled reactors have been encountered so far. It is shown that most of the failures occurred because flow-induced and acoustically induced dynamic loads were underestimated, while at the same time not enough was known about the influence of environmental parameters on material behavior. All problems encountered were solved. The comparison of the influence of the gas properties on acoustically induced and flow-induced vibration phenomena shows that the interaction between reactor design and the thermodynamic properties of the primary coolant precludes a general preference for either carbon dioxide or helium. The acoustic characteristics of CO 2 and He systems are different, but the difference in dynamic loadings due to the use of one rather than the other remains difficult to predict. A slight preference for helium seems, however, to be justified
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DEFF Research Database (Denmark)
Pedersen-Bjergaard, U; Andersen, M; Hansen, P B
1997-01-01
induced by non-cytotoxic drugs is characterised by heterogeneous clinical picture and recovery is generally rapid. Although corticosteroids seem inefficient, we still recommend that severe symptomatic cases of drug-induced thrombocytopenia are treated as idiopathic thrombocytopenic purpura due...
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Westerterp, K.R.
2004-01-01
OBJECTIVE: Daily energy expenditure consists of three components: basal metabolic rate, diet-induced thermogenesis and the energy cost of physical activity. Here, data on diet-induced thermogenesis are reviewed in relation to measuring conditions and characteristics of the diet. METHODS: Measuring
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S. Sleijfer (Stefan)
2001-01-01
textabstractThe cytotoxic agent bleomycin is feared for its induction of sometimes fatal pulmonary toxicity, also known as bleomycin-induced pneumonitis (BIP). The central event in the development of BIP is endothelial damage of the lung vasculature due to bleomycin-induced
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Blain, Hugues-Alexandre; Bailon, Salvador; Cuenca-Bescós, Gloria; Bennàsar, Maria; Rofes, Juan; López-García, Juan Manuel; Huguet, Rosa; Arsuaga, Juan Luis; Bermúdez de Castro, José Maria; Carbonell, Eudald
2010-11-01
The Sima del Elefante cave, in the Sierra de Atapuerca (Burgos, Spain), is famous for the fact that level TE9 of its Lower Red Unit recently delivered the oldest hominin remains of Western Europe, identified as Homo antecessor and dated by biostratigraphy and radiometric methods to ca 1.2 Ma. Given the importance of this discovery, every effort is being made to reconstruct the landscapes where these hominins once thrived. The amphibian and squamate reptile assemblage of the Sima del Elefante Lower Red Unit is here studied for the first time. The faunal list comprises at least 17 species (roughly 12,000 bone fossil remains): Salamandra salamandra, Triturus cf. marmoratus, Alytes obstetricans, Pelobates cultripes, Pelodytes punctatus, Bufo bufo, Bufo calamita, Hyla arborea, Rana sp., cf. Pelophylax sp., Lacerta s.l., small-sized indeterminate lacertids, Anguis fragilis, Natrix cf. natrix, Natrix cf. maura, Coronella cf. girondica and Vipera sp. As the amphibians and squamate reptiles do not differ at species level from the extant herpetofauna of the Iberian Peninsula, they can contribute to the reconstruction of the landscape and climate. In this paper, the mutual climatic range and habitat weighting methods are applied to the amphibian and squamate reptile assemblages in order to estimate quantitative data. The results from the squamate and amphibian study indicate that during the hominin presence the mean annual temperature (MAT = 10-13 °C) was always slightly warmer than at present and the mean annual precipitation (MAP = 800-1000 mm) was greater than today in the Burgos area. The landscape had open habitats in the vicinity of the Atapuerca caves throughout the sequence, with wet points in the surrounding area, and a predominance of humid meadows and open woodlands. These results mainly agree with those for large mammals, small mammals and the pollen analysis. The climate and landscape of TE-LRU are very similar to those reconstructed for the TD6 "Aurora Stratum
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Wang, P D; Lin, R S
1995-04-01
Induced abortion is widely practised in Taiwan; however, it had been illegal until 1985. It was of interest to investigate induced abortion practices in Taiwan after its legalization in 1985 in order to calculate the prevalence rate and ratio of induced abortion to live births and to pregnancies in Taiwan. A study using questionnaires through personal interviews was conducted on more than seventeen thousand women who attended a family planning service in Taipei metropolitan areas between 1991 and 1992. The reproductive history and sexual behaviour of the subjects were especially focused on during the interviews. Preliminary findings showed that 46% of the women had a history of having had an induced abortion. Among them, 54.8% had had one abortion, 29.7% had had two, and 15.5% had had three or more. The abortion ratio was 379 induced abortions per 1,000 live births and 255 per 1,000 pregnancies. The abortion ratio was highest for women younger than 20 years of age, for aboriginal women and for nulliparous women. When logistic regression was used to control for confounding variables, we found that the number of previous live births is the strongest predictor relating to women seeking induced abortion. In addition, a significant positive association exists between increasing number of induced abortions and cervical dysplasia.
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Paliperidone palmitate-induced sialorrhoea
Directory of Open Access Journals (Sweden)
Cengiz Cengisiz
2016-03-01
Full Text Available Extrapyramidal, metabolic, and cardiac side effects were reported for atypical antipsychotics; although a few resources show paliperidone-induced sialorrhea, there are no resources that show paliperidone palmitate-induced sialorrhea. In this paper, we present the paliperidone palmitate-induced sialorrhea side effects of a patient who applied on our clinic [Cukurova Med J 2016; 41(0.100: 8-13
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The ontogeny of kin recognition in tadpoles of the toad Bufo ...
Indian Academy of Sciences (India)
2016-08-26
Aug 26, 2016 ... Logo of the Indian Academy of Sciences ... Embryos and tadpoles of the toad were reared as ... Preference of test tadpoles to associate near the end compartments whether empty or containing members of specific stimulus ...
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Chemical Detection Based on Adsorption-Induced and Photo-Induced Stresses in MEMS Devices
Energy Technology Data Exchange (ETDEWEB)
Datskos, P.G.
1999-04-05
Recently there has been an increasing demand to perform real-time in-situ chemical detection of hazardous materials, contraband chemicals, and explosive chemicals. Currently, real-time chemical detection requires rather large analytical instrumentation that are expensive and complicated to use. The advent of inexpensive mass produced MEMS (micro-electromechanical systems) devices opened-up new possibilities for chemical detection. For example, microcantilevers were found to respond to chemical stimuli by undergoing changes in their bending and resonance frequency even when a small number of molecules adsorb on their surface. In our present studies, we extended this concept by studying changes in both the adsorption-induced stress and photo-induced stress as target chemicals adsorb on the surface of microcantilevers. For example, microcantilevers that have adsorbed molecules will undergo photo-induced bending that depends on the number of absorbed molecules on the surface. However, microcantilevers that have undergone photo-induced bending will adsorb molecules on their surfaces in a distinctly different way. Depending on the photon wavelength and microcantilever material, the microcantilever can be made to bend by expanding or contracting the irradiated surface. This is important in cases where the photo-induced stresses can be used to counter any adsorption-induced stresses and increase the dynamic range. Coating the surface of the microstructure with a different material can provide chemical specificity for the target chemicals. However, by selecting appropriate photon wavelengths we can change the chemical selectivity due to the introduction of new surface states in the MEMS device. We will present and discuss our results on the use of adsorption-induced and photo-induced bending of microcantilevers for chemical detection.
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Second-order nonlinearity induced transparency.
Zhou, Y H; Zhang, S S; Shen, H Z; Yi, X X
2017-04-01
In analogy to electromagnetically induced transparency, optomechanically induced transparency was proposed recently in [Science330, 1520 (2010)SCIEAS0036-807510.1126/science.1195596]. In this Letter, we demonstrate another form of induced transparency enabled by second-order nonlinearity. A practical application of the second-order nonlinearity induced transparency is to measure the second-order nonlinear coefficient. Our scheme might find applications in quantum optics and quantum information processing.
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An evaluation of a hubless inducer and a full flow hydraulic turbine driven inducer boost pump
Lindley, B. K.; Martinson, A. R.
1971-01-01
The purpose of the study was to compare the performance of several configurations of hubless inducers with a hydrodynamically similar conventional inducer and to demonstrate the performance of a full flow hydraulic turbine driven inducer boost pump using these inducers. A boost pump of this type consists of an inducer connected to a hydraulic turbine with a high speed rotor located in between. All the flow passes through the inducer, rotor, and hydraulic turbine, then into the main pump. The rotor, which is attached to the main pump shaft, provides the input power to drive the hydraulic turbine which, in turn, drives the inducer. The inducer, rotating at a lower speed, develops the necessary head to prevent rotor cavitation. The rotor speed is consistent with present main engine liquid hydrogen pump designs and the overall boost pump head rise is sufficient to provide adequate main pump suction head. This system would have the potential for operating at lower liquid hydrogen tank pressures.
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2017-10-20
REPORT TYPE 10/20/2017 Poster 4. TITLE AND SUBTITLE Inducible Laryngeal Obstrnction: Excessive Dynamic Airway Collapse vs. Inducible Laryngeal...REPORT b.ABSTRACT c. THIS PAGE ABSTRACT OF PAGES 3. DATES COVERED (From - To) 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER
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Smith, Kimberly G.
2006-01-01
Predation, competition, and their interaction are known to be important factors that influence the structure of ecological communities. In particular, in those cases where a competitive hierarchy exists among prey species, the presence of certain keystone predators can result in enhanced diversity in the prey community. However, little is known regarding the influence of keystone predator presence on invaded prey communities. Given the widespread occurrence of invasive species and substantial concern regarding their ecological impacts, studies on this topic are needed. In this study I used naturalistic replications of an experimental tadpole assemblage to assess the influence of predatory eastern newts, Notophthalmus viridescens, on the outcome of interspecific competition among native and nonindigenous tadpoles. When newts were absent, the presence of the tadpoles of one invasive species, the Cuban treefrog, Osteopilus septentrionalis, resulted in decreased survival and growth rate of the dominant native species, Bufo terrestris, and dominance of the tadpole assemblage by O. septentrionalis. However, the presence of one adult newt generally reduced or eliminated the negative impacts of O. septentrionalis tadpoles, resulting in comparable survival and performance of native species in invaded and noninvaded treatments. Differential mortality among the tadpole species suggests that newts preyed selectively on O. septentrionalis tadpoles, supporting the hypothesis that newts acted as keystone predators in the invaded assemblage. The presence of nonindigenous larval cane toads, Bufo marinus, did not significantly affect native species, and this species was not negatively affected by the presence of newts. Collectively, these results suggest that eastern newts significantly modified the competitive hierarchy of the invaded tadpole assemblage and reduced the impacts of a competitively superior invasive species. If general, these results suggest that the presence of
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Directory of Open Access Journals (Sweden)
Francesco Cerasoli
Full Text Available Boosted Regression Trees (BRT is one of the modelling techniques most recently applied to biodiversity conservation and it can be implemented with presence-only data through the generation of artificial absences (pseudo-absences. In this paper, three pseudo-absences generation techniques are compared, namely the generation of pseudo-absences within target-group background (TGB, testing both the weighted (WTGB and unweighted (UTGB scheme, and the generation at random (RDM, evaluating their performance and applicability in distribution modelling and species conservation. The choice of the target group fell on amphibians, because of their rapid decline worldwide and the frequent lack of guidelines for conservation strategies and regional-scale planning, which instead could be provided through an appropriate implementation of SDMs. Bufo bufo, Salamandrina perspicillata and Triturus carnifex were considered as target species, in order to perform our analysis with species having different ecological and distributional characteristics. The study area is the "Gran Sasso-Monti della Laga" National Park, which hosts 15 Natura 2000 sites and represents one of the most important biodiversity hotspots in Europe. Our results show that the model calibration ameliorates when using the target-group based pseudo-absences compared to the random ones, especially when applying the WTGB. Contrarily, model discrimination did not significantly vary in a consistent way among the three approaches with respect to the tree target species. Both WTGB and RDM clearly isolate the highly contributing variables, supplying many relevant indications for species conservation actions. Moreover, the assessment of pairwise variable interactions and their three-dimensional visualization further increase the amount of useful information for protected areas' managers. Finally, we suggest the use of RDM as an admissible alternative when it is not possible to individuate a suitable set of
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Ground Water Chemistry Changes before Major Earthquakes and Possible Effects on Animals
Grant, Rachel A.; Halliday, Tim; Balderer, Werner P.; Leuenberger, Fanny; Newcomer, Michelle; Cyr, Gary; Freund, Friedemann T.
2011-01-01
Prior to major earthquakes many changes in the environment have been documented. Though often subtle and fleeting, these changes are noticeable at the land surface, in water, in the air, and in the ionosphere. Key to understanding these diverse pre-earthquake phenomena has been the discovery that, when tectonic stresses build up in the Earth’s crust, highly mobile electronic charge carriers are activated. These charge carriers are defect electrons on the oxygen anion sublattice of silicate minerals, known as positive holes, chemically equivalent to O− in a matrix of O2−. They are remarkable inasmuch as they can flow out of the stressed rock volume and spread into the surrounding unstressed rocks. Travelling fast and far the positive holes cause a range of follow-on reactions when they arrive at the Earth’s surface, where they cause air ionization, injecting massive amounts of primarily positive air ions into the lower atmosphere. When they arrive at the rock-water interface, they act as •O radicals, oxidizing water to hydrogen peroxide. Other reactions at the rock-water interface include the oxidation or partial oxidation of dissolved organic compounds, leading to changes of their fluorescence spectra. Some compounds thus formed may be irritants or toxins to certain species of animals. Common toads, Bufo bufo, were observed to exhibit a highly unusual behavior prior to a M6.3 earthquake that hit L’Aquila, Italy, on April 06, 2009: a few days before the seismic event the toads suddenly disappeared from their breeding site in a small lake about 75 km from the epicenter and did not return until after the aftershock series. In this paper we discuss potential changes in groundwater chemistry prior to seismic events and their possible effects on animals. PMID:21776211
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Janin, Agnès; Léna, Jean-Paul; Deblois, Sandrine; Joly, Pierre
2012-10-01
The influence of landscape matrix on functional connectivity has been clearly established. Now methods to assess the effects of different land uses on species' movements are needed because current methods are often biased. The use of physiological parameters as indicators of the level of resistance to animal movement associated with different land uses (i.e., matrix resistance) could provide estimates of energetic costs and risks to animals migrating through the matrix. To assess whether corticosterone levels indicate matrix resistance, we conducted experiments on substrate choice and measured levels of corticosterone before and after exposure of toads (Bufo bufo) to 3 common substrates (ploughed soil, meadow, and forest litter). We expected matrix resistance and hormone levels to increase from forest litter (habitat of the toad) to meadows to ploughed soil. Adult toads had higher corticosterone levels on ploughed soil than on forest litter or meadow substrates. Hormone levels did not differ between forest litter and meadow. Toads avoided moving onto ploughed soil. Corticosterone levels in juvenile toads were not related to substrate type; however, hormone levels decreased as humidity increased. Juveniles, unlike adults, did not avoid moving over ploughed soil. The difference in responses between adult and juvenile toads may have been due to differences in experimental design (for juveniles, entire body used to measure corticosterone concentration; for adults, saliva alone); differences in the scale of sensory perception of the substrate (juveniles are much smaller than adults); or differences in cognitive processes between adult and juvenile toads. Adults probably had experience with different substrate types, whereas juveniles first emerging from the water probably did not. As a consequence, arable lands could act as ecological traps for juvenile toads. ©2012 Society for Conservation Biology.
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Directory of Open Access Journals (Sweden)
Lee Hyo-Jae
2012-12-01
Full Text Available Objectives: Toad venom, called Chan-Su, is a traditional Oriental medicine secreted from the auricular and the skin glands of the Bufo bufo gargarizanz Cantor or B. melanosticus Schneider and has been widely used in China, Korea and other parts of Asia for the treatment of pain, heart conditions, and cancer. We examined the concentrations of the main chemical constituents within a commerciallyavailable toad venom product and compared the levels for different extraction methods. Methods: Toad venom was extracted using either cold or hot water, ethanol (EtOH, methanol (MeOH, or ethyl acetate (EtOAc, was fractionated using precipitation or reflux, and was then analyzed using thin layer chromatography (TLC, high-performance liquid chromatography (HTLC, and liquid chroma-tography - mass spectrometry (LC-MS. Individual components were identified by comparisons of the retention times, the ultraviolet spectra, and mass spectras and differences in chemical constituents for different solvents and extraction methods are presented. Results:Components with authentic standards, including serotonin and bufodienolides (cinobufagen, bufalin, cinobufalin, and resibufogenin, were detected. The water extract of toad venom contained the greatest amount of serotonin (75.7 ± 0.1 mg/g, but very small amounts of bufodienolides (3.8 ± 0.0 mg/g. In contrast, the use of MeOH or EtOH extraction solutions resulted in 5-26 times higher concentrations of bufodienolides, with only trace amounts of serotonin. The relative and the absolute concentrations of the component also varied based on the extraction method; i.e., EtOH extracts yielded the greatest total amounts of bufodienolides, and EtOAc precipitation had the lowest amounts of bufodienolides. Conclusions: Toad venom consists of serotonin and several bufodienolides, and the choice of solvent to extract chemical the constituents is important as a way to enrich the purported active components for treating different
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Ground Water Chemistry Changes before Major Earthquakes and Possible Effects on Animals
Directory of Open Access Journals (Sweden)
Friedemann T. Freund
2011-06-01
Full Text Available Prior to major earthquakes many changes in the environment have been documented. Though often subtle and fleeting, these changes are noticeable at the land surface, in water, in the air, and in the ionosphere. Key to understanding these diverse pre-earthquake phenomena has been the discovery that, when tectonic stresses build up in the Earth’s crust, highly mobile electronic charge carriers are activated. These charge carriers are defect electrons on the oxygen anion sublattice of silicate minerals, known as positive holes, chemically equivalent to O– in a matrix of O2–. They are remarkable inasmuch as they can flow out of the stressed rock volume and spread into the surrounding unstressed rocks. Travelling fast and far the positive holes cause a range of follow-on reactions when they arrive at the Earth’s surface, where they cause air ionization, injecting massive amounts of primarily positive air ions into the lower atmosphere. When they arrive at the rock-water interface, they act as •O radicals, oxidizing water to hydrogen peroxide. Other reactions at the rock-water interface include the oxidation or partial oxidation of dissolved organic compounds, leading to changes of their fluorescence spectra. Some compounds thus formed may be irritants or toxins to certain species of animals. Common toads, Bufo bufo, were observed to exhibit a highly unusual behavior prior to a M6.3 earthquake that hit L’Aquila, Italy, on April 06, 2009: a few days before the seismic event the toads suddenly disappeared from their breeding site in a small lake about 75 km from the epicenter and did not return until after the aftershock series. In this paper we discuss potential changes in groundwater chemistry prior to seismic events and their possible effects on animals.
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Traffic forecasts ignoring induced demand
DEFF Research Database (Denmark)
Næss, Petter; Nicolaisen, Morten Skou; Strand, Arvid
2012-01-01
the model calculations included only a part of the induced traffic, the difference in cost-benefit results compared to the model excluding all induced traffic was substantial. The results show lower travel time savings, more adverse environmental impacts and a considerably lower benefitcost ratio when...... induced traffic is partly accounted for than when it is ignored. By exaggerating the economic benefits of road capacity increase and underestimating its negative effects, omission of induced traffic can result in over-allocation of public money on road construction and correspondingly less focus on other...... performance of a proposed road project in Copenhagen with and without short-term induced traffic included in the transport model. The available transport model was not able to include long-term induced traffic resulting from changes in land use and in the level of service of public transport. Even though...
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Hasegawa, Yasushi; Inoue, Tatsuro; Kawaminami, Satoshi; Fujita, Miho
2016-07-01
To evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801). Effect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test. Scallop shell extract significantly reduced scopolamine-induced short-term memory impairment and partially reduced scopolamine-induced spatial memory impairment in the Morris water maze test. Scallop shell extract suppressed scopolamine-induced elevation of acetylcholine esterase activity in the cerebral cortex. Treatment with scallop shell extract reversed the increase in locomotor activity induced by scopolamine. Scallop shell extract also suppressed the increase in locomotor activity induced by MK801. Our results provide initial evidence that scallop shell extract reduces scopolamine-induced memory impairment and suppresses MK-801-induced hyperlocomotion. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.
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CONSIDERAÇÕES SOBRE A ADAPTAÇÃO PARA AO AUDIOVISUAL: FICÇÃO NOIR
Directory of Open Access Journals (Sweden)
Marcelo Bulhões
2012-01-01
Full Text Available O propósito deste artigo é tratar da questão da adaptação audiovisual como fenômeno intersemiótico e de “tradução cultural”, enfocando um gênero cuja trajetória histórica é exemplar da dinâmica de absorção, transformação e recriação que envolve a relações entre cinema e a literatura: o noir. São avaliadas três realizações audiovisuais brasileiras: os filmes A Grande Arte, de Walter Salles Jr., e Bufo & Spallanzani, de Flávio Tambellini; e a minissérie televisiva Agosto, dirigida por Paulo José.
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Morard, Isabelle; Hadengue, Antoine
2008-09-03
Diarrhea is a frequent adverse event involving the most frequently antibiotics, laxatives and NSAI. Drug induced diarrhea may be acute or chronic. It may be due to expected, dose dependant properties of the drug, to immuno-allergic or bio-genomic mechanisms. Several pathophysiological mechanisms have been described resulting in osmotic, secretory or inflammatory diarrhea, shortened transit time, or malabsorption. Histopathological lesions sometimes associated with drug induced diarrhea are usually non specific and include ulcerations, inflammatory or ischemic lesions, fibrous diaphragms, microscopic colitis and apoptosis. The diagnosis of drug induced diarrhea, sometimes difficult to assess, relies on the absence of other obvious causes and on the rapid disappearance of the symptoms after withdrawal of the suspected drug.
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Ryu, JiHyeon; Lee, HeeYoung; Suh, JinUk; Yang, MyungSuk; Kang, WonKu; Kim, EunYoung
2015-01-01
We analyzed differences between spontaneously reported drug-induced (not including contrast media) and contrast media-induced adverse reactions. Adverse drug reactions reported by an in-hospital pharmacovigilance center (St. Mary's teaching hospital, Daejeon, Korea) from 2010-2012 were classified as drug-induced or contrast media-induced. Clinical patterns, frequency, causality, severity, Schumock and Thornton's preventability, and type A/B reactions were recorded. The trends among causality tools measuring drug and contrast-induced adverse reactions were analyzed. Of 1,335 reports, 636 drug-induced and contrast media-induced adverse reactions were identified. The prevalence of spontaneously reported adverse drug reaction-related admissions revealed a suspected adverse drug reaction-reporting rate of 20.9/100,000 (inpatient, 0.021%) and 3.9/100,000 (outpatients, 0.004%). The most common adverse drug reaction-associated drug classes included nervous system agents and anti-infectives. Dermatological and gastrointestinal adverse drug reactions were most frequently and similarly reported between drug and contrast media-induced adverse reactions. Compared to contrast media-induced adverse reactions, drug-induced adverse reactions were milder, more likely to be preventable (9.8% vs. 1.1%, p contrast media-induced adverse reactions (56.6%, p = 0.066). Causality patterns differed between the two adverse reaction classes. The World Health Organization-Uppsala Monitoring Centre causality evaluation and Naranjo algorithm results significantly differed from those of the Korean algorithm version II (p contrast media-induced adverse reactions. The World Health Organization-Uppsala Monitoring Centre and Naranjo algorithm causality evaluation afforded similar results.
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Troglitazone induced apoptosis via PPARγ activated POX-induced ROS formation in HT29 cells.
Wang, Jing; Lv, XiaoWen; Shi, JiePing; Hu, XiaoSong; DU, YuGuo
2011-08-01
In order to investigate the potential mechanisms in troglitazone-induced apoptosis in HT29 cells, the effects of PPARγ and POX-induced ROS were explored. [3- (4, 5)-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay, Annexin V and PI staining using FACS, plasmid transfection, ROS formation detected by DCFH staining, RNA interference, RT-PCR & RT-QPCR, and Western blotting analyses were employed to investigate the apoptotic effect of troglitazone and the potential role of PPARγ pathway and POX-induced ROS formation in HT29 cells. Troglitazone was found to inhibit the growth of HT29 cells by induction of apoptosis. During this process, mitochondria related pathways including ROS formation, POX expression and cytochrome c release increased, which were inhibited by pretreatment with GW9662, a specific antagonist of PPARγ. These results illustrated that POX upregulation and ROS formation in apoptosis induced by troglitazone was modulated in PPARγ-dependent pattern. Furthermore, the inhibition of ROS and apoptosis after POX siRNA used in troglitazone-treated HT29 cells indicated that POX be essential in the ROS formation and PPARγ-dependent apoptosis induced by troglitazone. The findings from this study showed that troglitazone-induced apoptosis was mediated by POX-induced ROS formation, at least partly, via PPARγ activation. Copyright © 2011 The Editorial Board of Biomedical and Environmental Sciences. Published by Elsevier B.V. All rights reserved.
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Baby universes with induced gravity
International Nuclear Information System (INIS)
Gao Yihong; Gao Hongbo
1989-01-01
In this paper some quantum effects of baby universes with induced gravity are discussed. It is proved that the interactions between the baby-parent universes are non-local, and argue that the induced low-energy cosmological constant is zero. This argument does not depend on the detail of the induced potential
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Energy Technology Data Exchange (ETDEWEB)
Xiao, Fei; Zhai, Zanjing; Jiang, Chuan; Liu, Xuqiang; Li, Haowei; Qu, Xinhua [Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Ouyang, Zhengxiao [Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Department of Orthopaedics, Hunan Provincial Tumor Hospital and Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan 410013 (China); Fan, Qiming; Tang, Tingting [Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Qin, An, E-mail: dr.qinan@gmail.com [Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Gu, Dongyun, E-mail: dongyungu@gmail.com [Department of Orthopedics, Shanghai Key Laboratory of Orthopedic Implant, Shanghai Ninth People' s Hospital, Shanghai Jiaotong University School of Medicine, Shanghai (China); Engineering Research Center of Digital Medicine and Clinical Translation, Ministry of Education of PR China (China); School of Biomedical Engineering, Shanghai Jiao Tong University, 1954 Huashan Road, Shanghai 200030 (China)
2015-01-01
Wear particle-induced osteolysis and subsequent aseptic loosening remains the most common complication that limits the longevity of prostheses. Wear particle-induced osteoclastogenesis is known to be responsible for extensive bone erosion that leads to prosthesis failure. Thus, inhibition of osteoclastic bone resorption may serve as a therapeutic strategy for the treatment of wear particle induced osteolysis. In this study, we demonstrated for the first time that geraniin, an active natural compound derived from Geranium thunbergii, ameliorated particle-induced osteolysis in a Ti particle-induced mouse calvaria model in vivo. We also investigated the mechanism by which geraniin exerts inhibitory effects on osteoclasts. Geraniin inhibited RANKL-induced osteoclastogenesis in a dose-dependent manner, evidenced by reduced osteoclast formation and suppressed osteoclast specific gene expression. Specially, geraniin inhibited actin ring formation and bone resorption in vitro. Further molecular investigation demonstrated geraniin impaired osteoclast differentiation via the inhibition of the RANKL-induced NF-κB and ERK signaling pathways, as well as suppressed the expression of key osteoclast transcriptional factors NFATc1 and c-Fos. Collectively, our data suggested that geraniin exerts inhibitory effects on osteoclast differentiation in vitro and suppresses Ti particle-induced osteolysis in vivo. Geraniin is therefore a potential natural compound for the treatment of wear particle induced osteolysis in prostheses failure. - Highlights: • Geraniin suppresses osteoclasts formation and function in vitro. • Geraniin impairs RANKL-induced nuclear factor-κB and ERK signaling pathway. • Geraniin suppresses osteolysis in vivo. • Geraniin may be used for treating osteoclast related diseases.
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Matsumoto, H.; Ohnishi, T.
There has been a recent upsurge of interest in radiation-induced adaptive response and bystander effect which are specific modes in stress response to low-dose low-dose rate radiation Recently we found that the accumulation of inducible nitric oxide NO synthase iNOS in wt p53 cells was induced by chronic irradiation with gamma rays followed by acute irradiation with X-rays but not by each one resulting in an increase in nitrite concentrations of medium It is suggested that the accumulation of iNOS may be due to the depression of acute irradiation-induced p53 functions by pre-chronic irradiation In addition we found that the radiosensitivity of wt p53 cells against acute irradiation with X-rays was reduced after chronic irradiation with gamma rays This reduction of radiosensitivity of wt p53 cells was nearly completely suppressed by the addition of NO scavenger carboxy-PTIO to the medium This reduction of radiosensitivity of wt p53 cells is just radiation-induced adaptive response suggesting that NO-mediated bystander effect may considerably contribute to adaptive response induced by radiation
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DEFF Research Database (Denmark)
Galle, Pia; Jensen, Lene; Andersson, Christina
2007-01-01
; yet they appear healthy and do not exhibit overt clinical or laboratory abnormalities. We induced comparable levels of aAb-IL-6 in different mouse strains by vaccination with immunogenic IL-6 analogues. We observed that the induced aAb-IL-6 protected against collagen-induced arthritis and experimental...
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... Home » Health Info » Hearing, Ear Infections, and Deafness Noise-Induced Hearing Loss On this page: What is ... I find additional information about NIHL? What is noise-induced hearing loss? Every day, we experience sound ...
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Boutroy, M J
1994-01-01
Drugs have been in the past and will in the future still be liable to induce apnea in neonates, infants and older children. At these different stages of development, the child may be abnormally vulnerable to respiratory disorders and apnea, and doses of drugs, without any abnormal side effects in adult patients, can be harmful in younger subjects. Drugs responsible for apnea during development are numerous, but more than half of the problems are induced by sedatives and hypnotics, among which phenothiazines, barbiturates, benzodiazepines (included transplacentally acquired) and general anesthetics are a few. Other pharmacological families are apnea inducers in the neonatal period and childhood: analgesics and opioid narcotics, agents acting at the levels of neuromuscular function and autonomic ganglia, and cardiovascular agents. The pathogenesis of these apneas depends on the disturbance of any mechanism responsible for the respiratory activity: medullary centers and brain stem structures, afferent influx to CNS, sleep stages, upper airways, lungs and respiratory muscles. At key stages such as birth and infancy, drugs may emphasize the particular sensitivity of the mechanisms responsible for inducing apnea. This might explain unexpected respiratory disorders during development.
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Irradiation-Induced Nanostructures
Energy Technology Data Exchange (ETDEWEB)
Birtcher, R.C.; Ewing, R.C.; Matzke, Hj.; Meldrum, A.; Newcomer, P.P.; Wang, L.M.; Wang, S.X.; Weber, W.J.
1999-08-09
This paper summarizes the results of the studies of the irradiation-induced formation of nanostructures, where the injected interstitials from the source of irradiation are not major components of the nanophase. This phenomena has been observed by in situ transmission electron microscopy (TEM) in a number of intermetallic compounds and ceramics during high-energy electron or ion irradiations when the ions completely penetrate through the specimen. Beginning with single crystals, electron or ion irradiation in a certain temperature range may result in nanostructures composed of amorphous domains and nanocrystals with either the original composition and crystal structure or new nanophases formed by decomposition of the target material. The phenomenon has also been observed in natural materials which have suffered irradiation from the decay of constituent radioactive elements and in nuclear reactor fuels which have been irradiated by fission neutrons and other fission products. The mechanisms involved in the process of this nanophase formation are discussed in terms of the evolution of displacement cascades, radiation-induced defect accumulation, radiation-induced segregation and phase decomposition, as well as the competition between irradiation-induced amorphization and recrystallization.
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Kim, Eun-Ae; Jang, Ji-Hoon; Lee, Yun-Han; Sung, Eon-Gi; Song, In-Hwan; Kim, Joo-Young; Kim, Suji; Sohn, Ho-Yong; Lee, Tae-Jin
2014-07-01
Dioscin, a saponin extracted from the roots of Polygonatum zanlanscianense, shows several bioactivities such as antitumor, antifungal, and antiviral properties. Although, dioscin is already known to induce cell death in variety cancer cells, the molecular basis for dioscin-induced cell death was not definitely known in cancer cells. In this study, we found that dioscin treatment induced cell death in dose-dependent manner in breast cancer cells such as MDA-MB-231, MDA-MB-453, and T47D cells. Dioscin decreased expressions of Bcl-2 and cIAP-1 proteins, which were down-regulated at the transcriptional level. Conversely, Mcl-1 protein level was down-regulated by facilitating ubiquitin/proteasome-mediated Mcl-1 degradation in dioscin-treated cells. Pretreatment with z-VAD fails to attenuate dioscin-induced cell death as well as caspase-mediated events such as cleavages of procaspase-3 and PARP. In addition, dioscin treatment increased the population of annexin V positive cells and induced DNA fragmentation in a dose-dependent manner in MDA-MB-231 cells. Furthermore, apoptosis inducing factor (AIF) was released from the mitochondria and translocated to the nucleus. Suppression in AIF expression by siRNA reduced dioscin-induced apoptosis in MDA-MB-231 cells. Taken together, our results demonstrate that dioscin-induced cell death was mediated via AIF-facilitating caspase-independent pathway as well as down-regulating anti-apoptotic proteins such as Bcl-2, cIAP-1, and Mcl-1 in breast cancer cells.
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Westerterp KR
2004-01-01
Objective Daily energy expenditure consists of three components: basal metabolic rate, diet-induced thermogenesis and the energy cost of physical activity. Here, data on diet-induced thermogenesis are reviewed in relation to measuring conditions and characteristics of the diet. Methods Measuring conditions include nutritional status of the subject, physical activity and duration of the observation. Diet characteristics are energy content and macronutrient composition. Resu...
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Quinine-induced tinnitus in rats.
Jastreboff, P J; Brennan, J F; Sasaki, C T
1991-10-01
Quinine ingestion reportedly induces tinnitus in humans. To expand our salicylate-based animal model of tinnitus, a series of conditioned suppression experiments was performed on 54 male-pigmented rats using quinine injections to induce tinnitus. Quinine induced changes in both the extent of suppression and recovery of licking, which followed a pattern that paralleled those produced after salicylate injections, and which may be interpreted as the result of tinnitus perception in animals. These changes depended on the dose and time schedule of quinine administration. Additionally, the calcium channel blocker, nimodipine, abolished the quinine-induced effect in a dose-dependent manner.
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Chronic lead exposure induces cochlear oxidative stress and potentiates noise-induced hearing loss.
Jamesdaniel, Samson; Rosati, Rita; Westrick, Judy; Ruden, Douglas M
2018-08-01
Acquired hearing loss is caused by complex interactions of multiple environmental risk factors, such as elevated levels of lead and noise, which are prevalent in urban communities. This study delineates the mechanism underlying lead-induced auditory dysfunction and its potential interaction with noise exposure. Young-adult C57BL/6 mice were exposed to: 1) control conditions; 2) 2 mM lead acetate in drinking water for 28 days; 3) 90 dB broadband noise 2 h/day for two weeks; and 4) both lead and noise. Blood lead levels were measured by inductively coupled plasma mass spectrometry analysis (ICP-MS) lead-induced cochlear oxidative stress signaling was assessed using targeted gene arrays, and the hearing thresholds were assessed by recording auditory brainstem responses. Chronic lead exposure downregulated cochlear Sod1, Gpx1, and Gstk1, which encode critical antioxidant enzymes, and upregulated ApoE, Hspa1a, Ercc2, Prnp, Ccl5, and Sqstm1, which are indicative of cellular apoptosis. Isolated exposure to lead or noise induced 8-12 dB and 11-25 dB shifts in hearing thresholds, respectively. Combined exposure induced 18-30 dB shifts, which was significantly higher than that observed with isolated exposures. This study suggests that chronic exposure to lead induces cochlear oxidative stress and potentiates noise-induced hearing impairment, possibly through parallel pathways. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
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Research progress of exercise-induced fatigue
Directory of Open Access Journals (Sweden)
Peng-yi DAI
2016-12-01
Full Text Available Exercise-induced fatigue is a comprehensive response to a variety of physiological and biochemical changes in the body, and can affect people's quality of life to different extents. If no timely recovery after occurrence of fatigue, accumulated gradually, it can lead to "burnout", a "overtraining syndrome", "chronic fatigue syndrome", etc., which will cause endocrine disturbance, immune suppression, even physical illness. Exercise-induced fatigue becomes an important factor endangering human health. In recent years, many experts and scholars at home and abroad are committed to the research of exercise-induced fatigue, and have put forward a variety of hypothesis to explain the cause of exercise-induced fatigue. They expect to find out the methods for preventing and eliminating exercise-induced fatigue. This article discusses mainly the pathogenesis, model building, elimination/ relief, etc. of exercise-induced fatigue to point out the research achievements of exercise-induced fatigue and its existing problems. DOI: 10.11855/j.issn.0577-7402.2016.11.14
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Terahertz Induced Electromigration
DEFF Research Database (Denmark)
Strikwerda, Andrew; Zalkovskij, Maksim; Iwaszczuk, Krzysztof
2014-01-01
We report the first observation of THz-field-induced electromigration in subwavelength metallic gap structures after exposure to intense single-cycle, sub-picosecond electric field transients of amplitude up to 400 kV/cm.......We report the first observation of THz-field-induced electromigration in subwavelength metallic gap structures after exposure to intense single-cycle, sub-picosecond electric field transients of amplitude up to 400 kV/cm....
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Salvant, B; Arduini, G; Assmann, R; Baglin, V; Barnes, M J; Bartmann, W; Baudrenghien, P; Berrig, O; Bracco, C; Bravin, E; Bregliozzi, G; Bruce, R; Bertarelli, A; Carra, F; Cattenoz, G; Caspers, F; Claudet, S; Day, H; Garlasche, M; Gentini, L; Goddard, B; Grudiev, A; Henrist, B; Jones, R; Kononenko, O; Lanza, G; Lari, L; Mastoridis, T; Mertens, V; Métral, E; Mounet, N; Muller, J E; Nosych, A A; Nougaret, J L; Persichelli, S; Piguiet, A M; Redaelli, S; Roncarolo, F; Rumolo, G; Salvachua, B; Sapinski, M; Schmidt, R; Shaposhnikova, E; Tavian, L; Timmins, M; Uythoven, J; Vidal, A; Wenninger, J; Wollmann, D; Zerlauth, M
2012-01-01
After the 2011 run, actions were put in place during the 2011/2012 winter stop to limit beam induced radio frequency (RF) heating of LHC components. However, some components could not be changed during this short stop and continued to represent a limitation throughout 2012. In addition, the stored beam intensity increased in 2012 and the temperature of certain components became critical. In this contribution, the beam induced heating limitations for 2012 and the expected beam induced heating limitations for the restart after the Long Shutdown 1 (LS1) will be compiled. The expected consequences of running with 25 ns or 50 ns bunch spacing will be detailed, as well as the consequences of running with shorter bunch length. Finally, actions on hardware or beam parameters to monitor and mitigate the impact of beam induced heating to LHC operation after LS1 will be discussed.
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Energy Technology Data Exchange (ETDEWEB)
Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu
2016-02-01
Phosphoramide mustard (PM) is an ovotoxic metabolite of cyclophosphamide and destroys primordial and primary follicles potentially by DNA damage induction. The temporal pattern by which PM induces DNA damage and initiation of the ovarian response to DNA damage has not yet been well characterized. This study investigated DNA damage initiation, the DNA repair response, as well as induction of follicular demise using a neonatal rat ovarian culture system. Additionally, to delineate specific mechanisms involved in the ovarian response to PM exposure, utility was made of PKC delta (PKCδ) deficient mice as well as an ATM inhibitor (KU 55933; AI). Fisher 344 PND4 rat ovaries were cultured for 12, 24, 48 or 96 h in medium containing DMSO ± 60 μM PM or KU 55933 (48 h; 10 nM). PM-induced activation of DNA damage repair genes was observed as early as 12 h post-exposure. ATM, PARP1, E2F7, P73 and CASP3 abundance were increased but RAD51 and BCL2 protein decreased after 96 h of PM exposure. PKCδ deficiency reduced numbers of all follicular stages, but did not have an additive impact on PM-induced ovotoxicity. ATM inhibition protected all follicle stages from PM-induced depletion. In conclusion, the ovarian DNA damage repair response is active post-PM exposure, supporting that DNA damage contributes to PM-induced ovotoxicity. - Highlights: • PM exposure induces DNA damage repair gene expression. • Inhibition of ATM prevented PM-induced follicle depletion. • PKCδ deficiency did not impact PM-induced ovotoxicity.
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Induced mutations in sesame breeding
International Nuclear Information System (INIS)
Ashri, A.
2001-01-01
The scope of induced mutations in sesame (Sesamum indicum L.) breeding is reviewed. So far in Egypt, India, Iraq, Rep. of Korea, and Sri Lanka, 14 officially released varieties have been developed through induced mutations: 12 directly and 2 through cross breeding (one using the 'dt45' induced mutant from Israel). For another variety released in China there are no details. The induced mutations approach was adopted primarily in order to obtain genetic variability that was not available in the germplasm collection. The mutagens commonly applied have been gamma rays, EMS and sodium azide. Sesame seeds can withstand high mutagen doses, and there are genotypic differences in sensitivity between varieties. The mutants induced in the above named countries and others include better yield, improved seed retention, determinate habit, modified plant architecture and size, more uniform and shorter maturation period, earliness, resistance to diseases, genic male sterility, seed coat color, higher oil content and modified fatty acids composition. Some of the induced mutants have already given rise to improved varieties, the breeding value of other mutants is now being assessed and still others can serve as useful markers in genetic studies and breeding programmes. (author)
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Holographic Two-Photon Induced Photopolymerization
Federal Laboratory Consortium — Holographic two-photon-induced photopolymerization (HTPIP) offers distinct advantages over conventional one-photon-induced photopolymerization and current techniques...
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Involvement of inducible nitric oxide synthase in radiation-induced vascular endothelial damage
International Nuclear Information System (INIS)
Hong, Chang-Won; Lee, Joon-Ho; Kim, Suwan; Noh, Jae Myoung; Kim, Young-Mee; Pyo, Hongryull; Lee, Sunyoung
2013-01-01
The use of radiation therapy has been linked to an increased risk of cardiovascular disease. To understand the mechanisms underlying radiation-induced vascular dysfunction, we employed two models. First, we examined the effect of X-ray irradiation on vasodilation in rabbit carotid arteries. Carotid arterial rings were irradiated with 8 or 16 Gy using in vivo and ex vivo methods. We measured the effect of acetylcholine-induced relaxation after phenylephrine-induced contraction on the rings. In irradiated carotid arteries, vasodilation was significantly attenuated by both irradiation methods. The relaxation response was completely blocked by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a potent inhibitor of soluble guanylate cyclase. Residual relaxation persisted after treatment with L-N ω -nitroarginine (L-NA), a non-specific inhibitor of nitric oxide synthase (NOS), but disappeared following the addition of aminoguanidine (AG), a selective inhibitor of inducible NOS (iNOS). The relaxation response was also affected by tetraethylammonium, an inhibitor of endothelium-derived hyperpolarizing factor activity. In the second model, we investigated the biochemical events of nitrosative stress in human umbilical-vein endothelial cells (HUVECs). We measured iNOS and nitrotyrosine expression in HUVECs exposed to a dose of 4 Gy. The expression of iNOS and nitrotyrosine was greater in irradiated HUVECs than in untreated controls. Pretreatment with AG, L-N 6 -(1-iminoethyl) lysine hydrochloride (a selective inhibitor of iNOS), and L-NA attenuated nitrosative stress. While a selective target of radiation-induced vascular endothelial damage was not definitely determined, these results suggest that NO generated from iNOS could contribute to vasorelaxation. These studies highlight a potential role of iNOS inhibitors in ameliorating radiation-induced vascular endothelial damage. (author)
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Systemic resistance induced by rhizosphere bacteria
Loon, L.C. van; Bakker, P.A.H.M.; Pieterse, C.M.J.
1998-01-01
Nonpathogenic rhizobacteria can induce a systemic resistance in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Rhizobacteria-mediated induced systemic resistance (ISR) has been demonstrated against fungi, bacteria, and viruses in Arabidopsis, bean,
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1970-01-01
A description of some of the problems and some of the advantages associated with the phenomenon of induced radioactivity at accelerator centres such as CERN. The author has worked in this field for several years and has recently written a book 'Induced Radioactivity' published by North-Holland.
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Mastication-induced vertigo and nystagmus.
Park, Seong-Ho; Kim, Hyo-Jung; Kim, Ji-Soo; Koo, Ja-Won; Oh, Seo Won; Kim, Dong-Uk; Kim, Joon-Tae; Welgampola, Miriam; Deriu, Franca
2014-03-01
Even though trigeminovestibular connections are well established in animals, mastication-induced dizziness has been described only as a vascular steal phenomenon in humans. We determined induction or modulation of nystagmus in two index patients with mastication-induced vertigo, 12 normal controls, and 52 additional patients with peripheral (n = 38, 26 with vestibular neuritis/labyrinthitis and 12 with Meniere's disease) or central (n = 14, 11 with Wallenberg syndrome, two with cerebellar infarction, and one with pontine infarction) vestibulopathy during their acute or compensated phase. Both index patients developed mastication-induced vertigo after near complete resolution of the spontaneous vertigo from presumed acute unilateral peripheral vestibulopathy. The nystagmus and vertigo gradually built up during mastication and dissipated slowly after cessation of mastication. Brain MRI and cerebral angiography were normal in these patients. Mastication did not induce nystagmus in normal controls. However, mastication induced nystagmus in five (24 %) of the 21 patients without spontaneous nystagmus (SN) but with a previous history of a vestibular syndrome, and either increased (21/31, 68 %) or decreased (7/31, 23 %) the SN in almost all the patients (28/31, 90 %) with SN. Mastication may induce significant vertigo and nystagmus in patients with a prior history of acute vestibulopathy. The induction or modulation of nystagmus by mastication in both peripheral and central vestibulopathies supports trigeminal modulation of the vestibular system in human. The gradual build-up and dissipation suggest a role of the velocity storage mechanism in the generation of mastication-induced vertigo and nystagmus.
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Mechanistic review of drug-induced steatohepatitis
International Nuclear Information System (INIS)
Schumacher, Justin D.; Guo, Grace L.
2015-01-01
Drug-induced steatohepatitis is a rare form of liver injury known to be caused by only a handful of compounds. These compounds stimulate the development of steatohepatitis through their toxicity to hepatocyte mitochondria; inhibition of beta-oxidation, mitochondrial respiration, and/or oxidative phosphorylation. Other mechanisms discussed include the disruption of phospholipid metabolism in lysosomes, prevention of lipid egress from hepatocytes, targeting mitochondrial DNA and topoisomerase, decreasing intestinal barrier function, activation of the adenosine pathway, increasing fatty acid synthesis, and sequestration of coenzyme A. It has been found that the majority of compounds that induce steatohepatitis have cationic amphiphilic structures; a lipophilic ring structure with a side chain containing a cationic secondary or tertiary amine. Within the last decade, the ability of many chemotherapeutics to cause steatohepatitis has become more evident coining the term chemotherapy-associated steatohepatitis (CASH). The mechanisms behind drug-induced steatohepatitis are discussed with a focus on cationic amphiphilic drugs and chemotherapeutic agents. - Highlights: • Reviewed the mechanisms underlying drug-induced steatohepatitis for many compounds • Mitochondrial dysfunction is critical in the development of drug-induced steatohepatitis. • Majority of drugs that induce steatohepatitis are cationic amphiphilic drugs. • Chemotherapeutics that induce CASH are cationic amphiphilic drugs. • Majority of drugs that induce steatohepatitis are carnitine palmitoyltransferase-I inhibitors.
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Mechanistic review of drug-induced steatohepatitis
Energy Technology Data Exchange (ETDEWEB)
Schumacher, Justin D., E-mail: Justin.d.schumacher@rutgers.edu; Guo, Grace L.
2015-11-15
Drug-induced steatohepatitis is a rare form of liver injury known to be caused by only a handful of compounds. These compounds stimulate the development of steatohepatitis through their toxicity to hepatocyte mitochondria; inhibition of beta-oxidation, mitochondrial respiration, and/or oxidative phosphorylation. Other mechanisms discussed include the disruption of phospholipid metabolism in lysosomes, prevention of lipid egress from hepatocytes, targeting mitochondrial DNA and topoisomerase, decreasing intestinal barrier function, activation of the adenosine pathway, increasing fatty acid synthesis, and sequestration of coenzyme A. It has been found that the majority of compounds that induce steatohepatitis have cationic amphiphilic structures; a lipophilic ring structure with a side chain containing a cationic secondary or tertiary amine. Within the last decade, the ability of many chemotherapeutics to cause steatohepatitis has become more evident coining the term chemotherapy-associated steatohepatitis (CASH). The mechanisms behind drug-induced steatohepatitis are discussed with a focus on cationic amphiphilic drugs and chemotherapeutic agents. - Highlights: • Reviewed the mechanisms underlying drug-induced steatohepatitis for many compounds • Mitochondrial dysfunction is critical in the development of drug-induced steatohepatitis. • Majority of drugs that induce steatohepatitis are cationic amphiphilic drugs. • Chemotherapeutics that induce CASH are cationic amphiphilic drugs. • Majority of drugs that induce steatohepatitis are carnitine palmitoyltransferase-I inhibitors.
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Full scale measurement of wind induced pressures : 1 configuration of wind induced pressures
Geurts, C.P.W.; Wijen, H.L.M.
1994-01-01
A research project 10 the spectral characteristics of wind induced pressures is in progress in Eindhoven. This project includes both wind tunnel and full scale measurements. Wind induced pressures are measured in full scale at the main building of Eindhoven University of Technology. This paper
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Directory of Open Access Journals (Sweden)
Tien-Ling Liao
2014-09-01
Full Text Available The exposure to dioxin can compromise pregnancy outcomes and increase the risk of preterm births. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD has been demonstrated to induce placental hypoxia at the end of pregnancy in a rat model, and hypoxia has been suggested to be the cause of abnormal trophoblast differentiation and placental insufficiency syndromes. In this study, we demonstrate that the non-hypoxic stimulation of human trophoblastic cells by TCDD strongly increased hypoxia inducible factor-1 alpha (HIF-1α stabilization. TCDD exposure induced the generation of reactive oxygen species (ROS and nitric oxide. TCDD-induced HIF-1α stabilization and Akt phosphorylation was inhibited by pretreatment with wortmannin (a phosphatidylinositol 3-kinase (PI3K inhibitor or N-acetylcysteine (a ROS scavenger. The augmented HIF-1α stabilization by TCDD occurred via the ROS-dependent activation of the PI3K/Akt pathway. Additionally, a significant increase in invasion and metallomatrix protease-9 activity was found in TCDD-treated cells. The gene expression of vascular endothelial growth factor and placental growth factor was induced upon TCDD stimulation, whereas the protein levels of peroxisome proliferator-activated receptor γ (PPARγ, PPARγ coactivator-1α, mitochondrial transcription factor, and uncoupling protein 2 were decreased. Our results indicate that an activated HIF-1α pathway, elicited oxidative stress, and induced metabolic stress contribute to TCDD-induced trophoblastic toxicity. These findings may provide molecular insight into the TCDD-induced impairment of trophoblast function and placental development.
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Directory of Open Access Journals (Sweden)
sima Hashemipour
2014-01-01
Full Text Available Background : Changes of serum minerals and vitamin D have been reported in anticonvulsant drugs user patients. The present study aimed at comparing the changes of serum minerals and vitamin D among two groups of enzyme-inducing and non enzyme-inducing anticonvulsant drug users. Methods: In this study 22 patients treated with enzyme-inducing drugs (carbamazepin, phenytoin, phenobarbital were compared to 25 patients of matched sex, age, and BMI treated with non enzyme-inducing drugs (sodium evaporate, lamotrigine. Serum calcium, phosphate, parathormone, and 25-hydroxy vitamin D were calculated in both groups. Calcium was measured by Calorimetery method. Parathormone and vitamin D were measured using ELISA method. Results: The mean serum vitamin D level was lower in enzyme-inducing than non enzyme-inducing drugs users (15.9±8.3 and 24.2±14.8, P=0.02. Frequency of vitamin D deficiency was higher in enzyme-inducing compared to non enzyme-inducing drugs users, 84% and 48% , respectively (P=0.016. The mean serum calcium level was significantly lower in enzyme-inducing drugs users. (8.7±0.2 vs. 9.0± 0.7, p= 0.05. Four percent in enzyme-inducing group compared to twenty four percent of non enzyme-inducing group had secondary hyperparathyroidism (P=0.016. Conclusion: While vitamin D deficiency is more frequent in enzyme-inducing drug users, secondary hyperparathyroidism is less frequent.
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Foote, F; Gale, K
1983-11-25
In a naloxone-reversible, dose-dependent manner, morphine (10-50 mg/kg i.p.) protected against seizures induced by maximal electroshock and increased the incidence and severity of seizures induced by bicuculline, in rats. Morphine also potentiated seizures induced by isoniazid and by picrotoxin. Thus, opiate activity influences the expression of seizures in contrasting ways depending upon the mode of seizure induction. Since morphine consistently potentiated seizures induced by interference with GABA transmission, it appears that GABAergic systems may be of particular significance for the elucidation of the varied effects of morphine on seizure susceptibility.
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Cisplatin-Induced Eosinophilic Pneumonia
Directory of Open Access Journals (Sweden)
Hideharu Ideguchi
2014-01-01
Full Text Available A 67-year-old man suffering from esophageal cancer was admitted to our hospital complaining of dyspnea and hypoxemia. He had been treated with cisplatin, docetaxel, and fluorouracil combined with radiotherapy. Chest computed tomography revealed bilateral ground-glass opacity, and bronchoalveolar lavage fluid showed increased eosinophils. Two episodes of transient eosinophilia in peripheral blood were observed after serial administration of anticancer drugs before the admission, and drug-induced lymphocyte stimulation test to cisplatin was positive. Thus cisplatin-induced eosinophilic pneumonia was suspected, and corticosteroid was effectively administered. To our knowledge, this is the first reported case of cisplatin-induced eosinophilic pneumonia.
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International Nuclear Information System (INIS)
Li Luming; Peng Xiang; Liu Cheng; Guo Hong; Chen Xuzong
2004-01-01
We observed a narrow linewidth (∼60 kHz) in a Doppler-broadened system showing electromagnetically induced transparency in caesium atomic vapour. The transition time induced reduction of the linewidth is illustrated both theoretically and experimentally
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Johansson, Henrik; Norlander, Katarina; Berglund, Lars; Janson, Christer; Malinovschi, Andrei; Nordvall, Lennart; Nordang, Leif; Emtner, Margareta
2015-01-01
Exercise-induced respiratory symptoms are common among adolescents. Exercise is a known stimulus for transient narrowing of the airways, such as exercise-induced bronchoconstriction (EIB) and exercise-induced laryngeal obstruction (EILO). Our aim was to investigate the prevalence of EIB and EILO in a general population of adolescents. In this cross-sectional study, a questionnaire on exercise-induced dyspnoea was sent to all adolescents born in 1997 and 1998 in Uppsala, Sweden (n=3838). A random subsample of 146 adolescents (99 with self-reported exercise-induced dyspnoea and 47 without this condition) underwent standardised treadmill exercise tests for EIB and EILO. The exercise test for EIB was performed while breathing dry air; a positive test was defined as a decrease of ≥10% in FEV1 from baseline. EILO was investigated using continuous laryngoscopy during exercise. The estimated prevalence of EIB and EILO in the total population was 19.2% and 5.7%, respectively. No gender differences were found. In adolescents with exercise-induced dyspnoea, 39.8% had EIB, 6% had EILO and 4.8% had both conditions. In this group, significantly more boys than girls had neither EIB nor EILO (64.7% vs 38.8%; p=0.026). There were no significant differences in body mass index, lung function, diagnosed asthma or medication between the participants with exercise-induced dyspnoea who had or did not have a positive EIB or EILO test result. Both EIB and EILO are common causes of exercise-induced dyspnoea in adolescents. EILO is equally common among girls and boys and can coexist with EIB. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
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2013-01-01
Background Emerging studies have demonstrated that pretreatment with electroacupuncture (EA) induces significant tolerance to focal cerebral ischemia. The present study seeks to determine the involvement of monocyte chemotactic protein-induced protein 1 (MCPIP1), a recently identified novel modulator of inflammatory reactions, in the cerebral neuroprotection conferred by EA pretreatment in the animal model of focal cerebral ischemia and to elucidate the mechanisms of EA pretreatment-induced ischemic brain tolerance. Methods Twenty-four hours after the end of the last EA pretreatment, focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 minutes in male C57BL/6 mice and MCPIP1 knockout mice. Transcription and expression of MCPIP1 gene was monitored by qRT-PCR, Western blot and immunohistochemistry. The neurobehavioral scores, infarction volumes, proinflammatory cytokines and leukocyte infiltration in brain and NF-κB signaling were evaluated after ischemia/reperfusion. Results MCPIP1 protein and mRNA levels significantly increased specifically in mouse brain undergoing EA pretreatment. EA pretreatment significantly attenuated the infarct volume, neurological deficits, upregulation of proinflammatory cytokines and leukocyte infiltration in the brain of wild-type mice after MCAO compared with that of the non-EA group. MCPIP1-deficient mice failed to evoke EA pretreatment-induced tolerance compared with that of the control MCPIP1 knockout group without EA treatment. Furthermore, the activation of NF-κB signaling was significantly reduced in EA-pretreated wild-type mice after MCAO compared to that of the non-EA control group and MCPIP1-deficient mice failed to confer the EA pretreatment-induced inhibition of NF-κB signaling after MCAO. Conclusions Our data demonstrated that MCPIP1 deficiency caused significant lack of EA pretreatment-induced cerebral protective effects after MCAO compared with the control group and that MCPIP1 is
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Directory of Open Access Journals (Sweden)
Hyun Jung Park
2016-11-01
Full Text Available Acellular bacterial ghosts (BGs are empty non-living bacterial cell envelopes, commonly generated by controlled expression of the cloned lysis gene E of bacteriophage PhiX174. In this study, Vibrio parahaemolyticus ghosts (VPGs were generated by chemically-induced lysis and the method is based on minimum inhibitory concentration (MIC of sodium hydroxide (NaOH, acetic acid, boric acid, citric acid, maleic acid, hydrochloric acid, and sulfuric acid. The MIC values of the respective chemicals were 3.125, 6.25, <50.0, 25.0, 6.25, 1.56, and 0.781 mg/mL. Except for boric acid, the lysis efficiency reached more than 99.99% at 5 min after treatment of all chemicals. Among those chemicals, NaOH-induced VPGs appeared completely DNA-free, which was confirmed by quantitative real-time PCR. Besides, lipopolysaccharides (LPS extracted from the NaOH-induced VPGs showed no distinctive band on SDS-PAGE gel after silver staining. On the other hand, LPS extracted from wild-type bacterial cells, as well as the organic acids-induced VPGs showed triple major bands and LPS extracted from the inorganic acids-induced VPGs showed double bands. It suggests that some surface structures in LPS of the NaOH-induced VPGs may be lost, weakened, or modified by the MIC of NaOH. Nevertheless, Limulus amoebocyte lysate assay revealed that there is no significant difference in endotoxic activity between the NaOH-induced VPGs and wild-type bacterial cells. Macrophages exposed to the NaOH-induced VPGs at 0.5 × 106 CFU/mL showed cell viability of 97.9%, however, the MIC of NaOH did not reduce the cytotoxic effect of wild-type bacterial cells. Like Escherichia coli LPS, the NaOH-induced VPGs are an excellent activator of pro-inflammatory cytokines (IL-1β and iNOS, anti-inflammatory cytokine (IL-10, and dual activities (IL-6 in the stimulated macrophage cells. On the other hand, the induction of TNF-α mRNA was remarkable in the macrophages exposed with wild-type cells. Scanning
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Statin-induced autoimmune necrotizing myositis
Directory of Open Access Journals (Sweden)
Katarzyna Ząber
2016-02-01
Full Text Available Myositides comprise a large group of disorders involving limb muscle weakness. In differential diagnosis we have to consider idiopathic myositides, myositides associated with other diseases, and those induced by external factors, e.g. drug-induced. Statins are commonly used drugs, but many patients experience a broad spectrum of adverse effects including symptoms from skeletal muscle. Physicians should pay special attention to patients reporting muscle weakness lasting longer than 12 weeks, despite statin withdrawal, as well as other symptoms: dysphagia, disturbed grip function, elevated creatinine kinase (CK levels and abnormal electromyography. The reported case deals with the problem of differential diagnosis of drug-induced muscle injury, polymyositis with a recently reported myopathy – statin-induced autoimmune necrotizing myositis, related to anti-HMGCR antibodies.
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Collision-induced destructive quantum interference
International Nuclear Information System (INIS)
Yang Xihua; Sun Zhenrong; Zhang Shi'an; Ding Liang'en; Wang Zugeng
2005-01-01
We conduct theoretical studies on the collision-induced destructive quantum interference of two-colour two-photon transitions in an open rhomb-type five-level system with a widely separated doublet by the density matrix approach. The effects of the collision-induced decay rates, the ratio of the transition dipole moments and the energy separation of the doublet on the interference are analysed. It is shown that a narrow dip appears in the excitation spectrum due to the collision-induced destructive interference, and that the narrow interference dip still exists even when the collision broadening is comparable to the energy separation of the doublet. The physical origin of the collision-induced destructive quantum interference is analysed in the dressed-atom picture
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Exotic Amphibians in the Pet Shops of Taiwan
Directory of Open Access Journals (Sweden)
Ping-Chun Lucy Hou
2006-06-01
Full Text Available Pet trade is an important mechanism for introducing alien species. We surveyed a total of 434 pet shops in major cities of Taiwan and found 49 species of alien amphibians belonging to 14 families and 31 genera. Two of the alien species, Rana catesbeiana and Kaloula pulchra, have established in the fields and the other three, Bufo marinus, Xenopus laevis, and Dendrobates auratus, have invasion records in other countries. There were 16 CITES Appendix II species. The most frequently displayed species were the horned frogs, eratophrys spp. And the most abundant species was the American Bullfrog, Rana catesbeiana. We urge the authority of Taiwan establishing regulations on pet trade and enforcing the wildlife conservation law to reduce the risks of alien species invasions.
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Molecular mechanisms of induced-mutations
International Nuclear Information System (INIS)
Kato, Takeshi
1985-01-01
The outcome of recent studies on mechanisms of induced-mutations is outlined with particular emphasis on the dependence of recA gene function in Escherichia coli. Genes involved in spontaneous mutation and x-ray- and chemical-induced mutation and genes involved in adaptive response are presented. As for SOS mutagenesis, SOS-induced regulation mechanisms and mutagenic routes are described. Furthermore, specificity of mutagens themselves are discussed in relation to mechanisms of base substitution, frameshift, and deletion mutagenesis. (Namekawa, K.)
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Kwon, Sunkuk; Sevick-Muraca, Eva M.
2017-01-01
Near-infrared fluorescence imaging (NIRFI) and far-red fluorescence imaging (FRFI) were used to investigate effects of depilation-induced skin pigmentation and diet-induced background fluorescence on fluorescent signal amplitude and lymphatic contraction frequency in C57BL6 mice. Far-red fluorescent signal amplitude, but not frequency, was affected by diet-induced fluorescence, which was removed by feeding the mice an alfalfa-free diet, and skin pigmentation further impacted the amplitude mea...
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International Nuclear Information System (INIS)
Jablon, Claude
1977-01-01
Research programs on laser-induced thermonuclear fusion in the United States, in Europe and in USSR are reviewed. The principle of the fusion reactions induced is explained, together with the theoretical effects of the following phenomena: power and type of laser beams, shape and size of the solid target, shock waves, and laser-hydrodynamics coupling problems [fr
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Neutron-induced fission cross sections
International Nuclear Information System (INIS)
Weigmann, H.
1991-01-01
In the history of fission research, neutron-induced fission has always played the most important role. The practical importance of neutron-induced fission rests upon the fact that additional neutrons are produced in the fission process, and thus a chain reaction becomes possible. The practical applications of neutron-induced fission will not be discussed in this chapter, but only the physical properties of one of its characteristics, namely (n,f) cross sections. The most important early summaries on the subject are the monograph edited by Michaudon which also deals with the practical applications, the earlier review article on fission by Michaudon, and the review by Bjornholm and Lynn, in which neutron-induced fission receives major attention. This chapter will attempt to go an intermediate way between the very detailed theoretical treatment in the latter review and the cited monograph which emphasizes the applied aspects and the techniques of fission cross-section measurements. The more recent investigations in the field will be included. Section II will survey the properties of cross sections for neutron-induced fission and also address some special aspects of the experimental methods applied in their measurement. Section Ill will deal with the formal theory of neutron-induced nuclear reactions for the resolved resonance region and the region of statistical nuclear reactions. In Section IV, the fission width, or fission transmission coefficient, will be discussed in detail. Section V will deal with the broader structures due to incompletely damped vibrational resonances, and in particular will address the special case of thorium and neighboring isotopes. Finally, Section VI will briefly discuss parity violation effects in neutron-induced fission. 74 refs., 14 figs., 3 tabs
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Rosuvastatin-induced pemphigoid.
LENUS (Irish Health Repository)
Murad, Aizuri A
2012-01-01
Statins are widely prescribed medications and very well tolerated. Rosuvastatin is another member of this drug used to treat dyslipidaemia. It is a competitive inhibitor of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase. Immunobullous disease is usually idiopathic but can be drug-induced. Both idiopathic and iatrogenic forms share common clinical and immunohistological features. The authors report a case of pemphigoid induced by rosuvastatin, a commonly prescribed medication. To our knowledge, there is limited report on rosuvastatin associated with pemphigoid in the literature.
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Small Molecular TRAIL Inducer ONC201 Induces Death in Lung Cancer Cells: A Preclinical Study
Feng, Yuan; Zhou, Jihong; Li, Zhanhua; Jiang, Ying; Zhou, Ying
2016-01-01
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) selectively targets cancer cells. The present preclinical study investigated the anti-cancer efficiency of ONC201, a first-in-class small molecule TRAIL inducer, in lung cancer cells. We showed that ONC201 was cytotoxic and anti-proliferative in both established (A549 and H460 lines) and primary human lung cancer cells. It was yet non-cytotoxic to normal lung epithelial cells. Further, ONC201 induced exogenous apoptosis act...
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Smad7 induces tumorigenicity by blocking TGF-beta-induced growth inhibition and apoptosis.
Halder, Sunil K; Beauchamp, R Daniel; Datta, Pran K
2005-07-01
Smad proteins play a key role in the intracellular signaling of the transforming growth factor beta (TGF-beta) superfamily of extracellular polypeptides that initiate signaling to regulate a wide variety of biological processes. The inhibitory Smad, Smad7, has been shown to function as intracellular antagonists of TGF-beta family signaling and is upregulated in several cancers. To determine the effect of Smad7-mediated blockade of TGF-beta signaling, we have stably expressed Smad7 in a TGF-beta-sensitive, well-differentiated, and non-tumorigenic cell line, FET, that was derived from human colon adenocarcinoma. Smad7 inhibits TGF-beta-induced transcriptional responses by blocking complex formation between Smad 2/3 and Smad4. While Smad7 has no effect on TGF-beta-induced activation of p38 MAPK and ERK, it blocks the phosphorylation of Akt by TGF-beta and enhances TGF-beta-induced phosphorylation of c-Jun. FET cells expressing Smad7 show anchorage-independent growth and enhance tumorigenicity in athymic nude mice. Smad7 blocks TGF-beta-induced growth inhibition by preventing TGF-beta-induced G1 arrest. Smad7 inhibits TGF-beta-mediated downregulation of c-Myc, CDK4, and Cyclin D1, and suppresses the expression of p21(Cip1). As a result, Smad7 inhibits TGF-beta-mediated downregulation of Rb phosphorylation. Furthermore, Smad7 inhibits the apoptosis of these cells. Together, Smad7 may increase the tumorigenicity of FET cells by blocking TGF-beta-induced growth inhibition and by inhibiting apoptosis. Thus, this study provides a mechanism by which a portion of human colorectal tumors may become refractory to tumor-suppressive actions of TGF-beta that might result in increased tumorigenicity.
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Directory of Open Access Journals (Sweden)
Dian Nugrahenny
2018-02-01
Full Text Available The administration of deoxy-corticosterone acetate (DOCA-salt can induce oxidative stress leading to decrease the bioavailability of nitric oxide (NO, increase senescence of circulating endothelial progenitor cells (EPCs, thus contributing to endothelial dysfunction. This study was aimed to investigate the effects of Physalis minima L. leaves extract on serum NO levels, circulating EPCs number, and histopathology of tail artery endothelial cells in DOCA-salt-induced endothelial dysfunction in rats. Twenty-five male Wistar rats were randomly divided into five groups: rats without any treatment (normal, rats treated with DOCA (10 mg/kgBW s.c. twice weekly and given 0.9% NaCl to drink ad libitum for 6 weeks, and DOCA-salt-induced rats orally supplemented with P. minima leaves extract at doses of 500, 1500, or 2500 mg/kgBW for 4 weeks. Serum NO levels were measured by colorimetry. The number of circulating EPCs (CD34+/CD133+ cells was determined by flow cytometry. The tail artery sections were histologically processed with hematoxylin-eosin staining. DOCA-salt-induced rats showed significantly (p<0.05 decrease in serum NO levels and circulating EPCs number compared to the normal. There was also more detached tail artery endothelial cells in DOCA-salt-induced rats. P. minima leaves extract at a dose of 500 mg/kgBW significantly (p<0.05 increased serum NO level and circulating EPCs number, and also induced an optimal re-endothelialization in DOCA-salt-induced rats. P. minima leave extract dose-dependently increases NO bioavailability contributing to enhanced EPCs mobilization, thereby promoting re-endothelialization in DOCA-salt-induced endothelial dysfunction in rats.
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International Nuclear Information System (INIS)
Madjid, Syahrun Nur; Idris, Nasrullah; Kurniawan, Koo Hendrik; Kagawa, Kiichiro
2011-01-01
In laser processing, suitable conditions for laser and gas play important role in ensuring a high quality of processing. To determine suitable conditions, we employed the electromagnetic phenomena associated with laser plasma generation. An electrode circuit was utilised to detect induced current due to the fast electrons propelled from the material during laser material processing. The characteristics of induced current were examined by changing parameters such as supplied voltage, laser pulse energy, number of laser shots, and type of ambient gas. These characteristics were compared with the optical emission characteristics. It was shown that the induced current technique proposed in this study is much more sensitive than the optical method in monitoring laser processing, that is to determine the precise focusing condition, and to accurately determine the moment of completion of laser beam penetration. In this study it was also shown that the induced current technique induced by CW CO 2 laser can be applied in industrial material processing for monitoring the penetration completion in a stainless steel plate drilling process.
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Self-Reports of Induced Abortion
DEFF Research Database (Denmark)
Rasch, V; Muhammad, H; Urassa, E
2000-01-01
OBJECTIVES: This study estimated the proportion of incomplete abortions that are induced in hospital-based settings in Tanzania. METHODS: A cross-sectional questionnaire study was conducted in 2 phases at 3 hospitals in Tanzania. Phase 1 included 302 patients with a diagnosis of incomplete abortion......, and phase 2 included 823 such patients. RESULTS: In phase 1, in which cases were classified by clinical criteria and information from the patient, 3.9% to 16.1% of the cases were classified as induced abortion. In phase 2, in which the structured interview was changed to an empathetic dialogue...... and previously used clinical criteria were omitted, 30.9% to 60.0% of the cases were classified as induced abortion. CONCLUSIONS: An empathetic dialogue improves the quality of data collected among women with induced abortion....
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Diffuse Transcranial Electrical Stimulation (DTES)-induced ...
African Journals Online (AJOL)
Higher voltages were needed to induce convulsion in pretreated animals than in normal animals. It is therefore suggestive that DTES-induced hypermotility can be used as an animal model for testing drugs that can be of advantage in the management of non convulsive (petit mal) status epilepticus (SE), and DTES induced ...
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Directory of Open Access Journals (Sweden)
Nastaran Faghihi
2015-04-01
Conclusion: The findings of the present study reveal that atorvastatin is able to prevent hyperglycemia-induced diabetic neuropathy and inhibit brain oxidative stress during diabetes. It is probable that reduction of urea is one of the reasons for atorvastatin prevention of hyperglycemia-induced neuropathy.
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Matsumoto, F; Watanabe, Y; Obi, T; Islam, M Z; Yamazaki-Himeno, E; Shiraishi, M; Miyamoto, A
2012-05-01
The aim of the present study was to clarify the responsiveness of the chicken basilar artery to 5-hydroxytryptamine (5-HT) and acetylcholine (ACh) and to characterize the related receptor subtypes in vitro. Basilar arteries were obtained from freshly slaughtered broiler chickens. The 5-HT induced concentration-dependent contraction of the arteries. The concentration-response curves for 5-HT were shifted 30-fold to the right by methiothepin (a 5-HT(1) and 5-HT(2) receptor antagonist) and 3-fold to the right by ketanserin (a 5-HT(2) receptor antagonist). In the presence of ketanserin, the concentration-response curve for 5-HT was shifted 10-fold to the right by methiothepin. The pA(2) value for methiothepin was 8.26. The ACh induced concentration-dependent relaxation under conditions of precontraction by 5-HT. The concentration-response curve for ACh was shifted to the right by atropine [a nonselective muscarinic (M) receptor antagonist] and hexahydro-sila-difenidol hydrochloride, a p-fluoroanalog (pFHHSiD, an M(3) receptor antagonist), but not by pirenzepine (an M(1) receptor antagonist) or methoctramine (an M(2) receptor antagonist). The pA(2) value for pFHHSiD was 7.55. Nω-Nitro-l-arginine (a nitric oxide synthase inhibitor) inhibited ACh-induced relaxation by approximately 50%. These results suggest that 5-HT induces contraction via activation of 5-HT(1) and 5-HT(2) receptors and that ACh induces relaxation via activation of the M(3) receptor. The 5-HT(1) receptor might play a dominant role in 5-HT-induced contraction. One of the factors involved in ACh-induced relaxation is probably nitric oxide released from endothelial cells.
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Energy Technology Data Exchange (ETDEWEB)
Yoshikawa, Yukitaka; Miyashita, Taishi; Higuchi, Satonori [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Tsuneyama, Koichi [Department of Diagnostic Pathology, Graduate School of Medicine and Pharmaceutical Science for Research, University of Toyama, Sugitani, Toyama 930‐0194 (Japan); Endo, Shinya [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Tsukui, Tohru [Research Center for Genomic Medicine, Saitama Medical University, Yamane, Hidaka 350‐1241 (Japan); Toyoda, Yasuyuki; Fukami, Tatsuki; Nakajima, Miki [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan); Yokoi, Tsuyoshi, E-mail: tyokoi@p.kanazawa-u.ac.jp [Drug Metabolism and Toxicology, Faculty of Pharmaceutical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920‐1192 (Japan)
2012-10-01
Although estrogen receptor (ER)α agonists, such as estradiol and ethinylestradiol (EE2), cause cholestasis in mice, they also reduce the degree of liver injury caused by hepatotoxicants as well as ischemia–reperfusion. The functional mechanisms of ERα have yet to be elucidated in drug-induced or chemical-induced liver injury. The present study investigated the effects of an ERα agonist, selective ER modulators (SERMs) and an ER antagonist on drug-induced and chemical-induced liver injuries caused by acetaminophen, bromobenzene, diclofenac, and thioacetamide (TA). We observed hepatoprotective effects of EE2, tamoxifen (TAM) and raloxifene pretreatment in female mice that were exposed to a variety of hepatotoxic compounds. In contrast, the ER antagonist did not show any hepatoprotective effects. DNA microarray analyses suggested that monocyte to macrophage differentiation-associated 2 (Mmd2) protein, which has an unknown function, is commonly increased by TAM and RAL pretreatment, but not by pretreatment with the ER antagonist. In ERα-knockout mice, the hepatoprotective effects of TAM and the increased expression of Mmd2 mRNA were not observed in TA-induced liver injury. To investigate the function of Mmd2, the expression level of Mmd2 mRNA was significantly knocked down to approximately 30% in mice by injection of siRNA for Mmd2 (siMmd2). Mmd2 knockdown resulted in a reduction of the protective effects of TAM on TA-induced liver injury in mice. This is the first report of the involvement of ERα in drug-induced or chemical-induced liver injury. Upregulation of Mmd2 protein in the liver was suggested as the mechanism of the hepatoprotective effects of EE2 and SERMs. -- Highlights: ► Liver injury induced by drugs or chemicals was investigated in mice. ► Liver injury was suppressed by pretreatment with tamoxifen in female mice. ► Mmd2, whose function was unknown, could be a candidate gene for liver protection. ► Tamoxifen up-regulated Mmd2 mRNA expression
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International Nuclear Information System (INIS)
Yoshikawa, Yukitaka; Miyashita, Taishi; Higuchi, Satonori; Tsuneyama, Koichi; Endo, Shinya; Tsukui, Tohru; Toyoda, Yasuyuki; Fukami, Tatsuki; Nakajima, Miki; Yokoi, Tsuyoshi
2012-01-01
Although estrogen receptor (ER)α agonists, such as estradiol and ethinylestradiol (EE2), cause cholestasis in mice, they also reduce the degree of liver injury caused by hepatotoxicants as well as ischemia–reperfusion. The functional mechanisms of ERα have yet to be elucidated in drug-induced or chemical-induced liver injury. The present study investigated the effects of an ERα agonist, selective ER modulators (SERMs) and an ER antagonist on drug-induced and chemical-induced liver injuries caused by acetaminophen, bromobenzene, diclofenac, and thioacetamide (TA). We observed hepatoprotective effects of EE2, tamoxifen (TAM) and raloxifene pretreatment in female mice that were exposed to a variety of hepatotoxic compounds. In contrast, the ER antagonist did not show any hepatoprotective effects. DNA microarray analyses suggested that monocyte to macrophage differentiation-associated 2 (Mmd2) protein, which has an unknown function, is commonly increased by TAM and RAL pretreatment, but not by pretreatment with the ER antagonist. In ERα-knockout mice, the hepatoprotective effects of TAM and the increased expression of Mmd2 mRNA were not observed in TA-induced liver injury. To investigate the function of Mmd2, the expression level of Mmd2 mRNA was significantly knocked down to approximately 30% in mice by injection of siRNA for Mmd2 (siMmd2). Mmd2 knockdown resulted in a reduction of the protective effects of TAM on TA-induced liver injury in mice. This is the first report of the involvement of ERα in drug-induced or chemical-induced liver injury. Upregulation of Mmd2 protein in the liver was suggested as the mechanism of the hepatoprotective effects of EE2 and SERMs. -- Highlights: ► Liver injury induced by drugs or chemicals was investigated in mice. ► Liver injury was suppressed by pretreatment with tamoxifen in female mice. ► Mmd2, whose function was unknown, could be a candidate gene for liver protection. ► Tamoxifen up-regulated Mmd2 mRNA expression
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Induced quantum conformal gravity
International Nuclear Information System (INIS)
Novozhilov, Y.V.; Vassilevich, D.V.
1988-11-01
Quantum gravity is considered as induced by matter degrees of freedom and related to the symmetry breakdown in the low energy region of a non-Abelian gauge theory of fundamental fields. An effective action for quantum conformal gravity is derived where both the gravitational constant and conformal kinetic term are positive. Relation with induced classical gravity is established. (author). 15 refs
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García-García, Fabio; Acosta-Peña, Eva; Venebra-Muñoz, Arturo; Murillo-Rodríguez, Eric
2009-08-01
Kuniomi Ishimori and Henri Piéron were the first researchers to introduce the concept and experimental evidence for a chemical factor that would presumably accumulate in the brain during waking and eventually induce sleep. This substance was named hypnotoxin. Currently, the variety of substances which have been shown to alter sleep includes peptides, cytokines, neurotransmitters and some substances of lipidic nature, many of which are well known for their involvement in other biological activities. In this chapter, we describe the sleep-inducing properties of the vasoactive intestinal peptide, prolactin, adenosine and anandamide.
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Directory of Open Access Journals (Sweden)
Juan P. Cerliani
2010-12-01
Full Text Available We have previously demonstrated a crosstalk between fibroblast growth factor 2 (FGF2 and progestins inducing experimental breast cancer growth. The aim of the present study was to compare the effects of FGF2 and of medroxyprogesterone acetate (MPA on the mouse mammary glands and to investigate whether the antiprogestin RU486 was able to reverse the MPA- or FGF2-induced effects on both, mammary gland and tumor growth. We demonstrate that FGF2 administered locally induced an intraductal hyperplasia that was not reverted by RU486, suggesting that FGF2-induced effects are progesterone receptor (PR-independent. However, MPA-induced paraductal hyperplasia was reverted by RU486 and a partial agonistic effect was observed in RU486-treated glands. Using C4-HD tumors which only grow in the presence of MPA, we showed that FGF2 administered intratumorally was able to stimulate tumor growth as MPA. The histology of FGF2-treated tumors showed different degrees of gland differentiation. RU486 inhibited both, MPA or FGF2 induced tumor growth. However, only complete regression was observed in MPA-treated tumors. Our results support the hypothesis that stromal FGF2 activates PR inducing hormone independent tumor growth.
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Gemcitabine-induced CXCL8 expression counteracts its actions by inducing tumor neovascularization
International Nuclear Information System (INIS)
Song, Yao; Baba, Tomohisa; Li, Ying-Yi; Furukawa, Kaoru; Tanabe, Yamato; Matsugo, Seiichi; Sasaki, Soichiro; Mukaida, Naofumi
2015-01-01
Patients with pancreatic ductal adenocarcinoma (PDAC) are frequently complicated with metastatic disease or locally advanced tumors, and consequently need chemotherapy. Gemcitabine is commonly used for PDAC treatment, but with limited efficacy. The capacity of gemcitabine to generate reactive oxygen species (ROS) in human pancreatic cancer cells, prompted us to examine its effects on the expression of pro-inflammatory cytokines and chemokines. We observed that gemcitabine enhanced selectively the expression of CXCL8 in human pancreatic cancer cells through ROS generation and NF-κB activation. In vitro blocking of CXCL8 failed to modulate gemcitabine-mediated inhibition of cell proliferation in human pancreatic cancer cells. Gemcitabine also enhanced CXCL8 expression in pancreatic cancer cells in xenografted tumor tissues. Moreover, anti-CXCL8 antibody treatment in vivo attenuated tumor formation as well as intra-tumoral vascularity in nude mice, which were transplanted with Miapaca-2 cells and treated with gemcitabine. Thus, gemcitabine-induced CXCL8 may counteract the drug through inducing neovascularization. - Highlights: • Gemcitabine induced CXCL8 expression in human pancreatic cancer cells. • CXCL8 expression required ROS generation and NF-κB activation. • CXCL8 did not affect in vitro proliferation of human pancreatic cancer cells. • CXCL8 in vivo counteracted gemcitabine by inducing neovascularization
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Gemcitabine-induced CXCL8 expression counteracts its actions by inducing tumor neovascularization
Energy Technology Data Exchange (ETDEWEB)
Song, Yao; Baba, Tomohisa [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192 (Japan); Li, Ying-Yi [Cancer Research Institute, Fudan University Shanghai Cancer Center, Department of Oncology, Shanghai Medical College, Fudan University, Shanghai (China); Furukawa, Kaoru; Tanabe, Yamato [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192 (Japan); School of Natural System Bioengineering Course, College of Science and Engineering, Kanazawa University, Kanazawa, Ishikawa (Japan); Matsugo, Seiichi [School of Natural System Bioengineering Course, College of Science and Engineering, Kanazawa University, Kanazawa, Ishikawa (Japan); Sasaki, Soichiro [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192 (Japan); Mukaida, Naofumi, E-mail: mukaida@staff.kanazawa-u.ac.jp [Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University, Kanazawa, Ishikawa 920-1192 (Japan)
2015-03-06
Patients with pancreatic ductal adenocarcinoma (PDAC) are frequently complicated with metastatic disease or locally advanced tumors, and consequently need chemotherapy. Gemcitabine is commonly used for PDAC treatment, but with limited efficacy. The capacity of gemcitabine to generate reactive oxygen species (ROS) in human pancreatic cancer cells, prompted us to examine its effects on the expression of pro-inflammatory cytokines and chemokines. We observed that gemcitabine enhanced selectively the expression of CXCL8 in human pancreatic cancer cells through ROS generation and NF-κB activation. In vitro blocking of CXCL8 failed to modulate gemcitabine-mediated inhibition of cell proliferation in human pancreatic cancer cells. Gemcitabine also enhanced CXCL8 expression in pancreatic cancer cells in xenografted tumor tissues. Moreover, anti-CXCL8 antibody treatment in vivo attenuated tumor formation as well as intra-tumoral vascularity in nude mice, which were transplanted with Miapaca-2 cells and treated with gemcitabine. Thus, gemcitabine-induced CXCL8 may counteract the drug through inducing neovascularization. - Highlights: • Gemcitabine induced CXCL8 expression in human pancreatic cancer cells. • CXCL8 expression required ROS generation and NF-κB activation. • CXCL8 did not affect in vitro proliferation of human pancreatic cancer cells. • CXCL8 in vivo counteracted gemcitabine by inducing neovascularization.
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Mitochondrial Swelling Induced by Glutathione
Lehninger, Albert L.; Schneider, Marion
1959-01-01
Reduced glutathione, in concentrations approximating those occurring in intact rat liver, causes swelling of rat liver mitochondria in vitro which is different in kinetics and extent from that yielded by L-thyroxine. The effect is also given by cysteine, which is more active, and reduced coenzyme A, but not by L-ascorbate, cystine, or oxidized glutathione. The optimum pH is 6.5, whereas thyroxine-induced swelling is optimal at pH 7.5. The GSH-induced swelling is not inhibited by DNP or dicumarol, nor by high concentrations of sucrose, serum albumin, or polyvinylpyrrolidone, in contrast to thyroxine-induced swelling. ATP inhibits the GSH swelling, but ADP and AMP are ineffective. Mn-+ is a very potent inhibitor, but Mg++ is ineffective. Ethylenediaminetetraacetate is also an effective inhibitor of GSH-induced swelling. The respiratory inhibitors amytal and antimycin A do not inhibit the swelling action of GSH, but cyanide does; these findings are consistent with the view that the oxidation-reduction state of the respiratory chain between cytochrome c and oxygen is a determinant of GSH-induced swelling. Reversal of GSH-induced swelling by osmotic means or by ATP in KCl media could not be observed. Large losses of nucleotides and protein occur during the swelling by GSH, suggesting that the action is irreversible. The characteristically drastic swelling action of GSH could be prevented if L-thyroxine was also present in the medium. PMID:13630941
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Induced gravity and gauge interactions revisited
International Nuclear Information System (INIS)
Broda, Boguslaw; Szanecki, Michal
2009-01-01
It has been shown that the primary, old-fashioned idea of Sakharov's induced gravity and gauge interactions, in the 'one-loop dominance' version, works astonishingly well yielding phenomenologically reasonable results. As a byproduct, the issue of the role of the UV cutoff in the context of the induced gravity has been reexamined (an idea of self-cutoff induced gravity). As an additional check, the black hole entropy has been used in the place of the action. Finally, it has been explicitly shown that the induced coupling constants of gauge interactions of the standard model assume qualitatively realistic values.
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Radiation-induced instability of human genome
International Nuclear Information System (INIS)
Ryabchenko, N.N.; Demina, Eh.A.
2014-01-01
A brief review is dedicated to the phenomenon of radiation-induced genomic instability where the increased level of genomic changes in the offspring of irradiated cells is characteristic. Particular attention is paid to the problems of genomic instability induced by the low-dose radiation, role of the bystander effect in formation of radiation-induced instability, and its relationship with individual radiosensitivity. We believe that in accordance with the paradigm of modern radiobiology the increased human individual radiosensitivity can be formed due to the genome instability onset and is a significant risk factor for radiation-induced cancer
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Uridine prevents fenofibrate-induced fatty liver.
Directory of Open Access Journals (Sweden)
Thuc T Le
Full Text Available Uridine, a pyrimidine nucleoside, can modulate liver lipid metabolism although its specific acting targets have not been identified. Using mice with fenofibrate-induced fatty liver as a model system, the effects of uridine on liver lipid metabolism are examined. At a daily dosage of 400 mg/kg, fenofibrate treatment causes reduction of liver NAD(+/NADH ratio, induces hyper-acetylation of peroxisomal bifunctional enzyme (ECHD and acyl-CoA oxidase 1 (ACOX1, and induces excessive accumulation of long chain fatty acids (LCFA and very long chain fatty acids (VLCFA. Uridine co-administration at a daily dosage of 400 mg/kg raises NAD(+/NADH ratio, inhibits fenofibrate-induced hyper-acetylation of ECHD, ACOX1, and reduces accumulation of LCFA and VLCFA. Our data indicates a therapeutic potential for uridine co-administration to prevent fenofibrate-induced fatty liver.
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Terbinafine-induced lichenoid drug eruption.
Zheng, Yue; Zhang, Jie; Chen, Haiyan; Lai, Wei; Maibach, Howard I
2017-03-01
Drug-induced lichen planus has been induced by antibiotics, anticonvulsants, antidiabetics, antimalarials, antitubercular drugs, antihypertensives, psychiatric drugs, chemotherapeutic agents, diuretic, heavy metals, NSAIDs, etc. Terbinafine, an antifungal agent, is widely used for dermatophyte infections and onychomycosis. Cutaneous adverse effects of terbinafine are rarely reported. Here, we report a case of terbinafine-induced lichenoid drug eruption in a 22-year-old who presented with generalized lichenoid eruption 2 weeks after terbinafine initiation of. The body and lip cleared completely after 8 weeks of drug withdrawal; nail change cleared after 12 weeks.
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Directory of Open Access Journals (Sweden)
Haelewyn Benoit
2011-04-01
Full Text Available Abstract Background The use and benefits of normobaric oxygen (NBO in patients suffering acute ischemic stroke is still controversial. Results Here we show for the first time to the best of our knowledge that NBO reduces both NMDA-induced calcium influxes in vitro and NMDA-induced neuronal degeneration in vivo, but increases oxygen and glucose deprivation-induced cell injury in vitro and ischemia-induced brain damage produced by middle cerebral artery occlusion in vivo. Conclusions Taken together, these results indicate that NBO reduces excitotoxin-induced calcium influx and subsequent neuronal degeneration but favors ischemia-induced brain damage and neuronal death. These findings highlight the complexity of the mechanisms involved by the use of NBO in patients suffering acute ischemic stroke.
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Hydroxyurea-Induced Replication Stress
Directory of Open Access Journals (Sweden)
Kenza Lahkim Bennani-Belhaj
2010-01-01
Full Text Available Bloom's syndrome (BS displays one of the strongest known correlations between chromosomal instability and a high risk of cancer at an early age. BS cells combine a reduced average fork velocity with constitutive endogenous replication stress. However, the response of BS cells to replication stress induced by hydroxyurea (HU, which strongly slows the progression of replication forks, remains unclear due to publication of conflicting results. Using two different cellular models of BS, we showed that BLM deficiency is not associated with sensitivity to HU, in terms of clonogenic survival, DSB generation, and SCE induction. We suggest that surviving BLM-deficient cells are selected on the basis of their ability to deal with an endogenous replication stress induced by replication fork slowing, resulting in insensitivity to HU-induced replication stress.
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Sun, Yuan; Liu, Chang; Chen, Ping-Xing; Liu, Liang
2018-02-01
People have been paying attention to the role of atoms' complex internal level structures in the research of electromagnetically induced transparency (EIT) for a long time, where the various degenerate Zeeman levels usually generate complex linkage patterns for the atomic transitions. It turns out, with special choices of the atomic states and the atomic transitions' linkage structure, clear signatures of quantum interference induced by the probe and coupling light's polarizations can emerge from a typical EIT phenomena. We propose to study a four-state system with double-V linkage pattern for the transitions and analyze the polarization-induced interference under the EIT condition. We show that such interference arises naturally under mild conditions on the optical field and atom manipulation techniques. Moreover, we construct a variation form of double-M linkage pattern where the polarization-induced interference enables polarization-dependent cross modulation between incident weak lights that can be effective even at the few-photon level. The theme is to gain more insight into the essential question: how can we build a nontrivial optical medium where incident lights experience polarization-dependent nonlinear optical interactions, valid for a wide range of incidence intensities down to the few-photon level?
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Induced abortion and subsequent pregnancy duration
DEFF Research Database (Denmark)
Zhou, Wei Jin; Sørensen, Henrik Toft; Olsen, Jørn
1999-01-01
OBJECTIVE: To examine whether induced abortion influences subsequent pregnancy duration. METHODS: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first-trimester ind......OBJECTIVE: To examine whether induced abortion influences subsequent pregnancy duration. METHODS: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first......-trimester induced abortions were compared with 46,026 whose pregnancies were not terminated by induced abortions. All subsequent pregnancies until 1994 were identified by register linkage. RESULTS: Preterm and post-term singleton live births were more frequent in women with one, two, or more previous induced...... abortions. After adjusting for potential confounders and stratifying by gravidity, the odds ratios of preterm singleton live births in women with one, two, or more previous induced abortions were 1.89 (95% confidence interval [CI] 1.70, 2.11), 2.66 (95% CI 2.09, 3.37), and 2.03 (95% CI 1.29, 3...
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Drug-induced cholestasis: mechanisms, models, and markers.
Chatterjee, Sagnik; Annaert, Pieter
2018-04-27
Drug-induced cholestasis is a risk factor in progression of drug candidates, and poses serious health hazard if not detected before going into human. Intrahepatic accumulation of bile acids (BAs) represents a characteristic phenomenon associated with drug-induced cholestasis. The major challenges in obtaining a complete understanding of drug-induced cholestasis lies in the complexity of BA-mediated toxicity mechanisms and the impact of bile acids at different 'targets' such as transporters, enzymes and nuclear receptors. At the same time, it is not trivial to have a relevant in vitro system that recapitulates these features. In addition, lack of sensitive and early preclinical biomarkers, relevant to the clinical situation, complicates proper detection of drug-induced cholestasis. Significant overlap in biomarker signatures between different mechanisms of drug-induced liver injury (DILI) precludes identification of specific mechanisms. Over the last decade the knowledge gaps in drug-induced cholestasis are closing due to growing mechanistic understanding of BA-mediated toxicity at (patho)physiologically relevant BA concentrations. Significant progress has been made in the mechanistic understanding of drug-induced cholestasis and associated toxicity, biomarkers and susceptibility factors. In addition, novel in vitro models are evolving which provide a holistic understanding of processes underlying drug-induced cholestasis. This review summarizes the challenges and recent understandings about drug-induced cholestasis with a potential path forward. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
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Magnetic-flutter-induced pedestal plasma transport
International Nuclear Information System (INIS)
Callen, J.D.; Hegna, C.C.; Cole, A.J.
2013-01-01
Plasma toroidal rotation can limit reconnection of externally applied resonant magnetic perturbation (RMP) fields δB on rational magnetic flux surfaces. Hence it causes the induced radial perturbations δB ρ to be small there, thereby inhibiting magnetic island formation and stochasticity at the top of pedestals in high (H-mode) confinement tokamak plasmas. However, the δB ρ s induced by RMPs increase away from rational surfaces and are shown to induce significant sinusoidal radial motion (flutter) of magnetic field lines with a radial extent that varies linearly with δB ρ and inversely with distance from the rational surface because of the magnetic shear. This produces a radial electron thermal diffusivity that is (1/2)(δB ρ /B 0 ) 2 times a kinetically derived, electron-collision-induced, magnetic-shear-reduced, effective parallel electron thermal diffusivity in the absence of magnetic stochasticity. These low collisionality flutter-induced transport processes and thin magnetic island effects are shown to be highly peaked in the vicinity of rational surfaces at the top of low collisionality pedestals. However, the smaller but finite level of magnetic-flutter-induced electron heat transport midway between rational surfaces is the primary factor that determines the electron temperature difference between rational surfaces at the pedestal top. The magnetic-flutter-induced non-ambipolar electron density transport can be large enough to push the plasma toward an electron density transport root. Requiring ambipolar density transport is shown to determine the radial electric field, the plasma toroidal rotation (via radial force balance), a reduced electron thermal diffusivity and increased ambipolar density transport in the pedestal. At high collisionality the various flutter effects are less strongly peaked at rational surfaces and generally less significant. They are thus less likely to exhibit flutter-induced resonant behaviour and transition toward an
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Magnetic-flutter-induced pedestal plasma transport
Callen, J. D.; Hegna, C. C.; Cole, A. J.
2013-11-01
Plasma toroidal rotation can limit reconnection of externally applied resonant magnetic perturbation (RMP) fields δB on rational magnetic flux surfaces. Hence it causes the induced radial perturbations δBρ to be small there, thereby inhibiting magnetic island formation and stochasticity at the top of pedestals in high (H-mode) confinement tokamak plasmas. However, the δBρs induced by RMPs increase away from rational surfaces and are shown to induce significant sinusoidal radial motion (flutter) of magnetic field lines with a radial extent that varies linearly with δBρ and inversely with distance from the rational surface because of the magnetic shear. This produces a radial electron thermal diffusivity that is (1/2)(δBρ/B0)2 times a kinetically derived, electron-collision-induced, magnetic-shear-reduced, effective parallel electron thermal diffusivity in the absence of magnetic stochasticity. These low collisionality flutter-induced transport processes and thin magnetic island effects are shown to be highly peaked in the vicinity of rational surfaces at the top of low collisionality pedestals. However, the smaller but finite level of magnetic-flutter-induced electron heat transport midway between rational surfaces is the primary factor that determines the electron temperature difference between rational surfaces at the pedestal top. The magnetic-flutter-induced non-ambipolar electron density transport can be large enough to push the plasma toward an electron density transport root. Requiring ambipolar density transport is shown to determine the radial electric field, the plasma toroidal rotation (via radial force balance), a reduced electron thermal diffusivity and increased ambipolar density transport in the pedestal. At high collisionality the various flutter effects are less strongly peaked at rational surfaces and generally less significant. They are thus less likely to exhibit flutter-induced resonant behaviour and transition toward an electron
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Energy Technology Data Exchange (ETDEWEB)
Lee, Sujeong, E-mail: crystalee@gmail.com [Next-generation Pharmaceutical Research Center, Korea Institute of Toxicology, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Lee, Hyang-Ae, E-mail: hyangaelee@gmail.com [Next-generation Pharmaceutical Research Center, Korea Institute of Toxicology, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 110-799 (Korea, Republic of); Human and Environmental Toxicology Program, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350 (Korea, Republic of); Choi, Sung Woo, E-mail: djmaya@snu.ac.kr [Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 110-799 (Korea, Republic of); Kim, Sung Joon, E-mail: sjoonkim@snu.ac.kr [Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 110-799 (Korea, Republic of); Kim, Ki-Suk, E-mail: idkks00@gmail.com [Next-generation Pharmaceutical Research Center, Korea Institute of Toxicology, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 305-343 (Korea, Republic of); Human and Environmental Toxicology Program, University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350 (Korea, Republic of)
2016-04-01
The recent establishment of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), which express the major cardiac ion channels and recapitulate spontaneous mechanical and electrical activities, may provide a possible solution for the lack of in vitro human-based cardiotoxicity testing models. Cardiotoxicity induced by the antidepressant nefazodone was previously revealed to cause an acquired QT prolongation by hERG channel blockade. To elucidate the cellular mechanisms underlying the cardiotoxicity of nefazodone beyond hERG, its effects on cardiac action potentials (APs) and ion channels were investigated using hiPSC-CMs with whole-cell patch clamp techniques. In a proof of principle study, we examined the effects of cardioactive channel blockers on the electrophysiological profile of hiPSC-CMs in advance of the evaluation of nefazodone. Nefazodone dose-dependently prolonged the AP duration at 90% (APD{sub 90}) and 50% (APD{sub 50}) repolarization, reduced the maximum upstroke velocity (dV/dt{sub max}) and induced early after depolarizations. Voltage-clamp studies of hiPSC-CMs revealed that nefazodone inhibited various voltage-gated ion channel currents including I{sub Kr}, I{sub Ks}, I{sub Na}, and I{sub Ca}. Among them, I{sub Kr} and I{sub Na} showed relatively higher sensitivity to nefazodone, consistent with the changes in the AP parameters. In summary, hiPSC-CMs enabled an integrated approach to evaluate the complex interactions of nefazodone with cardiac ion channels. These results suggest that hiPSC-CMs can be an effective model for detecting drug-induced arrhythmogenicity beyond the current standard assay of heterologously expressed hERG K{sup +} channels. - Highlights: • Nefazodone prolonged APD and decreased upstroke velocity of APs in hiPSC-CMs. • Nefazodone inhibited cardiac ion channels, especially I{sub Kr} and I{sub Na}, in hiPSC-CMs. • Nefazodone-induced AP changes are mainly the result of I{sub Kr} and I{sub Na} inhibition
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The role of hypoxia inducible factor-1 alpha in bypassing oncogene-induced senescence.
Directory of Open Access Journals (Sweden)
Mehtap Kilic Eren
Full Text Available Oncogene induced senescence (OIS is a sustained anti-proliferative response acutely induced in primary cells via activation of mitogenic oncogenes such as Ras/BRAF. This mechanism acts as an initial barrier preventing normal cells transformation into malignant cell. Besides oncogenic activation and DNA damage response (DDR, senescence is modulated by a plethora of other factors, and one of the most important one is oxygen tension of the tissue. The aim of this study was to determine the impact of hypoxia on RasV12-induced senescence in human diploid fibroblasts (HDFs. We showed here that hypoxia prevents execution of oncogene induced senescence (OIS, through a strong down-regulation of senescence hallmarks, such as SA- β-galactosidase, H3K9me3, HP1γ, p53, p21CIP1 and p16INK4a in association with induction of hypoxia inducible factor-1α (HIF-1α. In addition, hypoxia also decreased marks of H-RasV12-induced DDR in both cell lines through down-regulation of ATM/ATR, Chk1 and Chk2 phosphorylation as well as decreased γ-H2AX positivity. Utilizing shRNA system targeting HIF-1α we show that HIF-1α is directly involved in down regulation of p53 and its target p21CIP1 but not p16INK4a. In line with this finding we found that knock down of HIF-1α leads to a strong induction of apoptotic response, but not restoration of senescence in Ras expressing HDFs in hypoxia. This indicates that HIF-1α is an important player in early steps of tumorigenesis, leading to suppression of senescence through its negative regulation of p53 and p21CIP1. In our work we describe a mechanism through which hypoxia and specifically HIF-1α preclude cells from maintaining senescence-driven anti proliferative response. These findings indicate the possible mechanism through which hypoxic environment helps premalignant cells to evade impingement of cellular failsafe pathways.
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Congruence properties of induced representations
DEFF Research Database (Denmark)
Mayer, Dieter; Momeni, Arash; Venkov, Alexei
In this paper we study representations of the projective modular group induced from the Hecke congruence group of level 4 with Selberg's character. We show that the well known congruence properties of Selberg's character are equivalent to the congruence properties of the induced representations...
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Catecholamine induced cardiomyopathy in pheochromocytoma
Directory of Open Access Journals (Sweden)
Ron Thomas Varghese
2013-01-01
Full Text Available Catecholamine induced cardiomyopathy in the setting of pheochromocytoma is an unusual clinical entity. Earlier studies have reported left ventricular dysfunction in around 10% of subjects with pheochromocytoma. [1] Catecholamine induced vasoconstriction, direct toxic effect of byproducts of catecholamine degradation and direct receptor-mediated mechanisms are thought to contribute to cardiomyopathy in subjects with pheochromocytoma. The presentation remains a diagnostic challenge as patients may already have hypertensive heart disease and acute coronary syndrome on account of uncontrolled secondary hypertension. We report a case of a 42-year-old male, who presented with features of pheochromocytoma induced cardiomyopathy.
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Fermion-induced quantum critical points.
Li, Zi-Xiang; Jiang, Yi-Fan; Jian, Shao-Kai; Yao, Hong
2017-08-22
A unified theory of quantum critical points beyond the conventional Landau-Ginzburg-Wilson paradigm remains unknown. According to Landau cubic criterion, phase transitions should be first-order when cubic terms of order parameters are allowed by symmetry in the Landau-Ginzburg free energy. Here, from renormalization group analysis, we show that second-order quantum phase transitions can occur at such putatively first-order transitions in interacting two-dimensional Dirac semimetals. As such type of Landau-forbidden quantum critical points are induced by gapless fermions, we call them fermion-induced quantum critical points. We further introduce a microscopic model of SU(N) fermions on the honeycomb lattice featuring a transition between Dirac semimetals and Kekule valence bond solids. Remarkably, our large-scale sign-problem-free Majorana quantum Monte Carlo simulations show convincing evidences of a fermion-induced quantum critical points for N = 2, 3, 4, 5 and 6, consistent with the renormalization group analysis. We finally discuss possible experimental realizations of the fermion-induced quantum critical points in graphene and graphene-like materials.Quantum phase transitions are governed by Landau-Ginzburg theory and the exceptions are rare. Here, Li et al. propose a type of Landau-forbidden quantum critical points induced by gapless fermions in two-dimensional Dirac semimetals.
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Coelho, Sergio G; Yin, Lanlan; Smuda, Christoph; Mahns, Andre; Kolbe, Ludger; Hearing, Vincent J
2015-03-01
Repetitive suberythemal UVA and/or UVB exposures were used to generate comparable UV-induced tans in human skin over the course of 2 weeks. To evaluate the potential photoprotective values of those UVA- and/or UVB- induced tans and to avoid the confounding issue of residual UV-induced DNA damage, we waited 1 week before challenging those areas with a 1.5 MED of UVA+UVB after which we measure DNA damage. The results show that the type of UV used to induce skin pigmentation affects the redistribution of melanin in the skin and/or de novo melanin synthesis. The UVA-induced tans failed to even provide a minimal SPF of 1.5, which suggests that producing a tan with UVA-rich sunlamps prior to a holiday or vacation is completely counterproductive. Published 2014. This article is a US Government work and is in the public domain in the USA.
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Directory of Open Access Journals (Sweden)
Pei Wang
2013-09-01
Full Text Available Background/Aims: The mechanisms involved in endothelial barrier dysfunction induced by hypoxia are incompletely understood. There is debate about the role of hypoxia-inducible factor-1α (HIF-1α in endothelial barrier disruption. The aim of this study was to investigate the effect of genetic overexpression of HIF-1α on barrier function and the underlying mechanisms in hypoxic endothelial cells. Methods: The plasmid pcDNA3.1/V5-His-HIF-1α was stably transfected into human endothelial cells. The cells were exposed to normoxia or hypoxia. The mRNA and protein expressions of HIF-1α were detected by RT-PCR and Western blot respectively. The barrier function was assessed by measuring the transendothelial electrical resistance (TER. The Western blot analysis was used to determine the protein expression of glucose transporter-1 (GLUT-1, zonular occludens-1 (ZO-1, occludin, and myosin light chain kinase (MLCK in endothelial cells. The mRNA expression of proinflammatory cytokines was detected by qRT-PCR. Results: Genetic overexpression of HIF-1α significantly increased the mRNA and protein expression of HIF-1α in endothelial cells. The overexpression of HIF-1α enhanced the hypoxia-induced increase of HIF-1α and GLUT-1 protein expression. HIF-1α overexpression not only exacerbated hypoxia-induced endothelial barrier dysfunction but also augmented hypoxia-induced up-regulation of MLCK protein expression. HIF-1α overexpression also enhanced IL-1β, IL-6 and TNF-α mRNA expression. Conclusion: We provide evidence that genetic overexpression of HIF-1α aggravates the hypoxia-induced endothelial barrier dysfunction via enhancing the up-regulation of MLCK protein expression caused by hypoxia, suggesting a potential role for HIF-1α in the pathogenesis of endothelial barrier dysfunction in hypoxia.
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Exercise induced asthma and endogenous opioids.
Gaillard, R C; Bachman, M; Rochat, T; Egger, D; de Haller, R; Junod, A F
1986-01-01
Concentrations of endogenous opioid peptides in the plasma are increased during exercise and these substances have been implicated in the pathogenesis of asthma induced by chloropropramide and alcohol in diabetic patients. This work was undertaken to determine whether exercise induced asthma might be mediated by endogenous opioids. Plasma beta endorphin, met-enkephalin, and adrenocorticotrophic hormone (ACTH) concentrations were measured in five asthmatic patients and five normal volunteers breathing cold air during exercise. In four of the patients the effect of an infusion of naloxone on FEV1 was also measured during exercise induced asthma. Exercise produced acute bronchoconstriction in all asthmatics, characterised by a fall in FEV1; whereas no change occurred in normal subjects. There was no difference in plasma met-enkephalin, beta endorphin, and ACTH concentration between the two groups. Infusion of naloxone neither prevented nor worsened exercise induced asthma. These data suggest that endogenous opioids probably do not play a part in the development of exercise induced asthma. PMID:2944240
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The origin of electromagnetically induced absorption
International Nuclear Information System (INIS)
Park, Jong Dae; Hwang, Sung Tae; Lee, Ho Seong; Park, Sung Jong; Cho, Hyuck; Choi, Won Sik
2000-01-01
Recently, there have been a lot of interests in the coherence superposition of atomic states which are formed by laser fields. Coherent population trapping(CTP), electromagnetically induced transparency(EIT), enhancement of the refractive index without absorption, lasing without inversion(LWI), and electromagnetically induced absorption(EIA) are the examples where coherence effects are important. Previously, the spontaneous transfer of the light-induced coherence from the excited level to the ground one was emphasized for the essential ingredient for electromagnetically induced absorption. In this paper, we have considered a case where linearly polarized coupling laser and probe laser are applied to the same degenerated ground and excited levels. We have solved the master equations for density matrix using time varying Hamiltonian and studied the absorption spectra at various conditions. We demonstrate that EIA can be observed without spontaneous transfer of the light-induced coherence in F g = 1 -> F e = 2 D2 transitions of Hydrogen atoms
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Hahn, Hyung Jin; Youn, Hae Jeong; Cha, Hwa Jun; Kim, Karam; An, Sungkwan
2016-01-01
Background We are continually exposed to low-dose radiation (LDR) in the range 0.1 Gy from natural sources, medical devices, nuclear energy plants, and other industrial sources of ionizing radiation. There are three models for the biological mechanism of LDR: the linear no-threshold model, the hormetic model, and the threshold model. Objective We used keratinocytes as a model system to investigate the molecular genetic effects of LDR on epidermal cell differentiation. Methods To identify keratinocyte differentiation, we performed western blots using a specific antibody for involucrin, which is a precursor protein of the keratinocyte cornified envelope and a marker for keratinocyte terminal differentiation. We also performed quantitative polymerase chain reaction. We examined whether LDR induces changes in involucrin messenger RNA (mRNA) and protein levels in calcium-induced keratinocyte differentiation. Results Exposure of HaCaT cells to LDR (0.1 Gy) induced p21 expression. p21 is a key regulator that induces growth arrest and represses stemness, which accelerates keratinocyte differentiation. We correlated involucrin expression with keratinocyte differentiation, and examined the effects of LDR on involucrin levels and keratinocyte development. LDR significantly increased involucrin mRNA and protein levels during calcium-induced keratinocyte differentiation. Conclusion These studies provide new evidence for the biological role of LDR, and identify the potential to utilize LDR to regulate or induce keratinocyte differentiation. PMID:27489424
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Shao, Fenli; Tan, Tao; Tan, Yang; Sun, Yang; Wu, Xingxin; Xu, Qiang
2016-09-01
Psoriasis is a chronic inflammatory skin disease with excessive activation of toll-like receptors (TLRs), which play important roles in developing psoriasis. Targeting TLR signaling remains a challenge for treating psoriasis. Here, we found that andrographolide (Andro), a small-molecule natural product, alleviated imiquimod- but not interleukin 23 (IL-23)-induced psoriasis in mice with reducing expressions of IL-23 and IL-1β in the skin. The improvement in imiquimod-induced psoriasis by Andro was not observed in microtubule-associated protein 1 light chain 3 beta (MAP1LC3B) knockout mice. Furthermore, Andro inhibited mRNA expressions of IL-23, IL-6 and IL-1β but not CD80 and CD86 in bone-marrow derived dendritic cells (BMDCs) treated with lipopolysaccharide (LPS) in a MAP1LC3B-dependent manner. In addition, Andro inhibited imiquimod-induced mRNA expressions of IL-23, IL-6, IL-1β, CD80 and CD86 in BMDCs from mice. Interestingly, Andro induced a degradation of myeloid differentiation factor 88 (MyD88) and blocked the recruitment of TNF receptor-associated factor 6 (TRAF6) to MyD88 upon LPS stimulation in BMDCs from mice. Blockade of autophagic proteolysis using NH4Cl or MAP1LC3B(-/-) BMDCs abolished the Andro-induced MyD88 degradation. In conclusion, Andro controls activation of MyD88-dependent cytokines and alleviates psoriasis in mice via inducing autophagic proteolysis of MyD88, which could be a novel strategy to treat psoriasis. Copyright © 2016 Elsevier Inc. All rights reserved.
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International Nuclear Information System (INIS)
Ichihashi, M.; Ueda, M.; Budiyanto, A.; Bito, T.; Oka, M.; Fukunaga, M.; Tsuru, K.; Horikawa, T.
2003-01-01
Solar radiation induces acute and chronic reactions in human and animal skin. Chronic repeated exposures are the primary cause of benign and malignant skin tumors, including malignant melanoma. Among types of solar radiation, ultraviolet B (290-320 nm) radiation is highly mutagenic and carcinogenic in animal experiments compared to ultraviolet A (320-400 nm) radiation. Epidemiological studies suggest that solar UV radiation is responsible for skin tumor development via gene mutations and immunosuppression, and possibly for photoaging. In this review, recent understanding of DNA damage caused by direct UV radiation and by indirect stress via reactive oxygen species (ROS) and DNA repair mechanisms, particularly nucleotide excision repair of human cells, are discussed. In addition, mutations induced by solar UV radiation in p53, ras and patched genes of non-melanoma skin cancer cells, and the role of ROS as both a promoter in UV-carcinogenesis and an inducer of UV-apoptosis, are described based primarily on the findings reported during the last decade. Furthermore, the effect of UV on immunological reaction in the skin is discussed. Finally, possible prevention of UV-induced skin cancer by feeding or topical use of antioxidants, such as polyphenols, vitamin C, and vitamin E, is discussed
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Food-Induced Acute Pancreatitis.
Manohar, Murli; Verma, Alok K; Upparahalli Venkateshaiah, Sathisha; Goyal, Hemant; Mishra, Anil
2017-12-01
Food allergy, a commonly increasing problem worldwide, defined as an adverse immune response to food. A variety of immune-related effector cells such as mast cells, eosinophils, neutrophils, and T cells are involved in food-related allergic responses categorized as IgE mediated, non-IgE mediated, and mixed (IgE and non-IgE) depending upon underlying immunological mechanisms. The dietary antigens mainly target the gastrointestinal tract including pancreas that gets inflamed due to food allergy and leads acute pancreatitis. Reports indicate several food proteins induce pancreatitis; however, detailed underlying mechanism of food-induced pancreatitis is unexplored. The aim of the review is to understand and update the current scenario of food-induced pancreatitis. A comprehensive literature search of relevant research articles has been performed through PubMed, and articles were chosen based on their relevance to food allergen-mediated pancreatitis. Several cases in the literature indicate that acute pancreatitis has been provoked after the consumption of mustard, milk, egg, banana, fish, and kiwi fruits. Food-induced pancreatitis is an ignored and unexplored area of research. The review highlights the significance of food in the development of pancreatitis and draws the attention of physicians and scientists to consider food allergies as a possible cause for initiation of pancreatitis pathogenesis.
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Olfactory-Induced Synesthesias: A Review and Model
Stevenson, Richard J.; Tomiczek, Caroline
2007-01-01
Recent reviews of synesthesia concentrate upon rare neurodevelopmental examples and exclude common olfactory-induced experiences with which they may profitably be compared. Like the neurodevelopmental synesthesias, odor-induced experiences involve different sensory modalities; are reliable, asymmetric (concurrents cannot induce), and automatic;…
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Directory of Open Access Journals (Sweden)
Alexandru D P Papoiu
2011-03-01
Full Text Available Histamine is the prototypical pruritogen used in experimental itch induction. However, in most chronic pruritic diseases, itch is not predominantly mediated by histamine. Cowhage-induced itch, on the other hand, seems more characteristic of itch occurring in chronic pruritic diseases.We tested the validity of cowhage as an itch-inducing agent by contrasting it with the classical itch inducer, histamine, in healthy subjects and atopic dermatitis (AD patients. We also investigated whether there was a cumulative effect when both agents were combined.Fifteen healthy individuals and fifteen AD patients were recruited. Experimental itch induction was performed in eczema-free areas on the volar aspects of the forearm, using different itch inducers: histamine, cowhage and their combination thereof. Itch intensity was assessed continuously for 5.5 minutes after stimulus application using a computer-assisted visual analogue scale (COVAS.In both healthy and AD subjects, the mean and peak intensity of itch were higher after the application of cowhage compared to histamine, and were higher after the combined application of cowhage and histamine, compared to histamine alone (p<0.0001 in all cases. Itch intensity ratings were not significantly different between healthy and AD subjects for the same itch inducer used; however AD subjects exhibited a prolonged itch response in comparison to healthy subjects (p<0.001.Cowhage induced a more intense itch sensation compared to histamine. Cowhage was the dominant factor in itch perception when both pathways were stimulated in the same time. Cowhage-induced itch is a suitable model for the study of itch in AD and other chronic pruritic diseases, and it can serve as a new model for testing antipruritic drugs in humans.
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Methylphenidate Actively Induces Emergence from General Anesthesia
Solt, Ken; Cotten, Joseph F.; Cimenser, Aylin; Wong, Kin F.K.; Chemali, Jessica J.; Brown, Emery N.
2011-01-01
Background Although accumulating evidence suggests that arousal pathways in the brain play important roles in emergence from general anesthesia, the roles of monoaminergic arousal circuits are unclear. In this study we tested the hypothesis that methylphenidate (an inhibitor of dopamine and norepinephrine transporters) induces emergence from isoflurane anesthesia. Methods Using adult rats we tested the effect of methylphenidate IV on time to emergence from isoflurane anesthesia. We then performed experiments to test separately for methylphenidate-induced changes in arousal and changes in minute ventilation. A dose-response study was performed to test for methylphenidate–induced restoration of righting during continuous isoflurane anesthesia. Surface electroencephalogram recordings were performed to observe neurophysiological changes. Plethysmography recordings and arterial blood gas analysis were performed to assess methylphenidate-induced changes in respiratory function. Droperidol IV was administered to test for inhibition of methylphenidate's actions. Results Methylphenidate decreased median time to emergence from 280 to 91 s. The median difference in time to emergence without compared to with methylphenidate was 200 [155, 331] s (median, [95% confidence interval]). During continuous inhalation of isoflurane, methylphenidate induced return of righting in a dose-dependent manner, induced a shift in electroencephalogram power from delta to theta, and induced an increase in minute ventilation. Administration of droperidol (0.5 mg/kg IV) prior to methylphenidate (5 mg/kg IV) largely inhibited methylphenidate-induced emergence behavior, electroencephalogram changes, and changes in minute ventilation. Conclusions Methylphenidate actively induces emergence from isoflurane anesthesia by increasing arousal and respiratory drive, possibly through activation of dopaminergic and adrenergic arousal circuits. Our findings suggest that methylphenidate may be clinically
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Radiotherapy-Induced Skin Reactions Induce Fibrosis Mediated by TGF-β1 Cytokine
Directory of Open Access Journals (Sweden)
Cherley Borba Vieira de Andrade
2017-04-01
Full Text Available Purpose: This study aimed to investigate radiation-induced lesions on the skin in an experimental animal model. Methods and Materials: Cutaneous wounds were induced in Wistar rats by 4 MeV energy electron beam irradiation, using a dose rate of 240 cGy/min, for 3 different doses (10 Gy, 40 Gy, and 60 Gy. The skin was observed 5, 10, and 25 days (D after ionizing radiation exposition. Results: Infiltrate inflammatory process was observed in D5 and D10, for the 40 Gy and 60 Gy groups, and a progressive increase of transforming growth factor β1 is associated with this process. It could also be noted a mischaracterization of collagen fibers at the high-dose groups. Conclusion: It was observed that the lesions caused by ionizing radiation in rats were very similar to radiodermatitis in patients under radiotherapy treatment. Advances in Knowledge: This study is important to develop strategies to prevent radiation-induced skin reactions.
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Diversity and dynamics of amphibians in floodplain ecosystems of the Samara river
Directory of Open Access Journals (Sweden)
O. V. Zhukov
2015-04-01
Full Text Available High emphasis is placed on amphibian importance as a buffer system, which has inhibiting effect on technogenic transformation of biogeocoenoses. Issues of the animals’ use in biological restoration, ecological rehabilitation of technogenic landscapes and in bioindication of environmental conditions are covered. Сhange in any component of the ecosystem leads to changing of the whole ecosystem. Anuran amphibians are extremely vulnerable to harmful effects of many factors of natural and anthropogenic origin. That is why, the destruction of forests, draining of wetlands, global climate change, global and local environmental pollution lead to complete disappearance or drastic decrease in numbers of many species of amphibians, reduction and fragmentation of their habitats, increased diversity and overall proportion of morphological anomalies in the natural populations of this group of animals. Recent studies of morphological changes in amphibians are increasingly being used to assess the state of the natural state of their populations and quality of their environment. In the biogeocenoses which are in the conditions of transformation amphibians have a number of advantages relative to their activity, the rate of reproduction, and euribiont character. Practical recommendations on protection and enrichment of the regional herpetofauna are given. The impact of the number and species diversity of amphibians on forest ecosystems of the steppe Dnieperin various conditions is assessed. Parametric entropy factors, the coefficient of biodiversity helped to identify the dominant species of amphibians. Taking into account the influence of predictors, there is the possibility to determine the number and species diversity of amphibians in the conditions of floodplain lime-ash forest. As a result of recording, the following species were caught: Pelobates fuscus (Laurenti, 1768, Rana arvalis Nilsson, 1842, Bufo bufo (Linnaeus, 1758, Bombina bombina (Linnaeus, 1758
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Intoxicação por veneno de sapo em um canino Toad venom intoxication in a dog
Directory of Open Access Journals (Sweden)
Luciana Sonne
2008-09-01
Full Text Available O sapo do gênero Bufo possui nas suas glândulas paratóides uma secreção mucóide contendo toxinas como bufaginas e Bufotoxinas, que são esteróides cardiogênicos. Os cães podem atacar os sapos, entrando em contato com o veneno por meio das mucosas. Um canino, da raça Bulldog Francês, foi encaminhado ao Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (UFRGS para a necropsia com histórico de provável intoxicação por veneno de sapo. Na necropsia o canino apresentava pulmões aumentados de volume, avermelhados e com edema, e rins de coloração vermelho-escura. As alterações microscópicas indicaram congestão, hemorragia e edema pulmonar. Nos rins, no baço e nos linfonodos foi observada congestão. As análises toxicológicas para os venenos de rotina foram negativas. Porém, a investigação do veneno de sapo a partir de cromatografia por camada delgada e gasosa demonstrou resultado positivo, revelando ser esta a causa da morte do canino.The toads of the genus Bufo produce, in their parotoid glands, a mucoid secretion containing toxins such as bufagins and Bufotoxins, which are cardiogenic steroids. The mucous membranes of dogs can absorb this venom when they attack the toads. A French bulldog with a history of probable toad venom intoxication was referred to Veterinary Pathology Section of Federal University of Rio Grande do Sul (UFRGS for necropsy. The necropsy revealed enlarged, reddish, edematous lungs, and kidneys displaying a dark red color. The microscopic alterations indicated the presence of congestion, hemorrhage, and pulmonary edema. Congestion was observed in the kidneys, spleen and lymph nodes. The routine toxicological analyses for venom detection were negative. Nevertheless, the toad venom test result was positive as assessed by thin layer and gas chromatography, indicating that toad venom intoxication was the cause of death.
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Energy Technology Data Exchange (ETDEWEB)
Sharma, Bhupesh, E-mail: drbhupeshresearch@gmail.com; Sharma, P.M.
2013-11-15
Arsenic toxicity has been reported to damage all the major organs including the brain and vasculature. Dementia including Alzheimer's disease (AD) and vascular dementia (VaD) are posing greater risk to the world population as it is now increasing at a faster rate. We have investigated the role of sodium butyrate, a selective histone deacetylase (HDAC) inhibitor and aminoguanidine, a selective inducible nitric oxide synthase (iNOS) inhibitor in pharmacological interdiction of arsenic toxicity induced vascular endothelial dysfunction and dementia in rats. Arsenic toxicity was done by administering arsenic drinking water to rats. Morris water-maze (MWM) test was used for assessment of learning and memory. Endothelial function was assessed using student physiograph. Oxidative stress (aortic superoxide anion, serum and brain thiobarbituric acid reactive species, brain glutathione) and nitric oxide levels (serum nitrite/nitrate) were also measured. Arsenic treated rats have shown impairment of endothelial function, learning and memory, reduction in serum nitrite/nitrate and brain GSH levels along with increase in serum and brain TBARS. Sodium butyrate as well as aminoguanidine significantly convalesce arsenic induced impairment of learning, memory, endothelial function, and alterations in various biochemical parameters. It may be concluded that arsenic induces endothelial dysfunction and dementia, whereas, sodium butyrate, a HDAC inhibitor as well as aminoguanidine, a selective iNOS inhibitor may be considered as potential agents for the management of arsenic induced endothelial dysfunction and dementia. - Highlights: • As has induced endothelial dysfunction (Edf) and vascular dementia (VaD). • As has increased oxidative stress, AChE activity and decreased serum NO. • Inhibitors of HDAC and iNOS have attenuated As induced Edf and VaD. • Both the inhibitors have attenuated As induced biochemical changes. • Inhibitor of HDAC and iNOS has shown good potential
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International Nuclear Information System (INIS)
Sharma, Bhupesh; Sharma, P.M.
2013-01-01
Arsenic toxicity has been reported to damage all the major organs including the brain and vasculature. Dementia including Alzheimer's disease (AD) and vascular dementia (VaD) are posing greater risk to the world population as it is now increasing at a faster rate. We have investigated the role of sodium butyrate, a selective histone deacetylase (HDAC) inhibitor and aminoguanidine, a selective inducible nitric oxide synthase (iNOS) inhibitor in pharmacological interdiction of arsenic toxicity induced vascular endothelial dysfunction and dementia in rats. Arsenic toxicity was done by administering arsenic drinking water to rats. Morris water-maze (MWM) test was used for assessment of learning and memory. Endothelial function was assessed using student physiograph. Oxidative stress (aortic superoxide anion, serum and brain thiobarbituric acid reactive species, brain glutathione) and nitric oxide levels (serum nitrite/nitrate) were also measured. Arsenic treated rats have shown impairment of endothelial function, learning and memory, reduction in serum nitrite/nitrate and brain GSH levels along with increase in serum and brain TBARS. Sodium butyrate as well as aminoguanidine significantly convalesce arsenic induced impairment of learning, memory, endothelial function, and alterations in various biochemical parameters. It may be concluded that arsenic induces endothelial dysfunction and dementia, whereas, sodium butyrate, a HDAC inhibitor as well as aminoguanidine, a selective iNOS inhibitor may be considered as potential agents for the management of arsenic induced endothelial dysfunction and dementia. - Highlights: • As has induced endothelial dysfunction (Edf) and vascular dementia (VaD). • As has increased oxidative stress, AChE activity and decreased serum NO. • Inhibitors of HDAC and iNOS have attenuated As induced Edf and VaD. • Both the inhibitors have attenuated As induced biochemical changes. • Inhibitor of HDAC and iNOS has shown good potential in
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Energy Technology Data Exchange (ETDEWEB)
Ozeki, Nobuaki; Hase, Naoko; Yamaguchi, Hideyuki; Hiyama, Taiki; Kawai, Rie [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Kondo, Ayami [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan); Nakata, Kazuhiko [Department of Endodontics, School of Dentistry, Aichi Gakuin University, 2-11 Suemori-dori, Chikusa-ku, Nagoya, Aichi 464-8651 (Japan); Mogi, Makio, E-mail: makio@dpc.agu.ac.jp [Department of Medicinal Biochemistry, School of Pharmacy, Aichi Gakuin University, 1-100 Kusumoto, Chikusa-ku, Nagoya 464-8650 (Japan)
2015-05-01
Inorganic polyphosphate [Poly(P)] may represent a physiological source of phosphate and has the ability to induce bone differentiation in osteoblasts. We previously reported that cytokine-induced matrix metalloproteinase (MMP)-3 accelerates the proliferation of purified odontoblast-like cells. In this study, MMP-3 small interfering RNA (siRNA) was transfected into odontoblast-like cells derived from induced pluripotent stem cells to investigate whether MMP-3 activity is induced by Poly(P) and/or is associated with cell proliferation and differentiation into odontoblast-like cells. Treatment with Poly(P) led to an increase in both cell proliferation and additional odontoblastic differentiation. Poly(P)-treated cells showed a small but significant increase in dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP-1) mRNA expression, which are markers of mature odontoblasts. The cells also acquired additional odontoblast-specific properties including adoption of an odontoblastic phenotype typified by high alkaline phosphatase (ALP) activity and a calcification capacity. In addition, Poly(P) induced expression of MMP-3 mRNA and protein, and increased MMP-3 activity. MMP-3 siRNA-mediated disruption of the expression of these effectors potently suppressed the expression of odontoblastic biomarkers ALP, DSPP, and DMP-1, and blocked calcification. Interestingly, upon siRNA-mediated silencing of MMP-3, we noted a potent and significant decrease in cell proliferation. Using specific siRNAs, we revealed that a unique signaling cascade, Poly(P)→MMP-3→DSPP and/or DMP-1, was intimately involved in the proliferation of odontoblast-like cells. - Highlights: • Polyphosphate increases proliferation of iPS cell-derived odontoblast-like cells. • Polyphosphate-induced MMP-3 results in an increase of cell proliferation. • Induced cell proliferation involves MMP-3, DSPP, and/or DMP-1 sequentially. • Induced MMP-3 also results in an increase of odontoblastic
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Directory of Open Access Journals (Sweden)
Wei-Chun Huang
Full Text Available Pulmonary arterial hypertension (PAH is characterized by progressive increases in vascular resistance and the remodeling of pulmonary arteries. The accumulation of inflammatory cells in the lung and elevated levels of inflammatory cytokines in the bloodstream suggest that inflammation may play a role in PAH. In this study, the benefits of induced pluripotent stem cells (iPSCs and iPSC-conditioned medium (iPSC CM were explored in monocrotaline (MCT-induced PAH rats. We demonstrated that both iPSCs and iPSC CM significantly reduced the right ventricular systolic pressure and ameliorated the hypertrophy of the right ventricle in MCT-induced PAH rats in models of both disease prevention and disease reversal. In the prevention of MCT-induced PAH, iPSC-based therapy led to the decreased accumulation of inflammatory cells and down-regulated the expression of the IL-1β, IL-6, IL-12α, IL-12β, IL-23 and IFNγ genes in lung specimens, which implied that iPSC-based therapy may be involved in the regulation of inflammation. NF-κB signaling is essential to the inflammatory cascade, which is activated via the phosphorylation of the NF-κB molecule. Using the chemical inhibitor specifically blocked the phosphorylation of NF-κB, and in vitro assays of cultured human M1 macrophages implied that the anti-inflammation effect of iPSC-based therapy may contribute to the disturbance of NF-κB activation. Here, we showed that iPSC-based therapy could restore the hemodynamic function of right ventricle with benefits for preventing the ongoing inflammation in the lungs of MCT-induced PAH rats by regulating NF-κB phosphorylation.
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Directory of Open Access Journals (Sweden)
Denise Pereira Müzell
2013-06-01
Full Text Available This study assessed the bioactive properties of an aqueous extract of M. officinalis for its anti-inflammatory activity and its protection against hepatic and renal lesions induced by acetaminophen (APAP. Animals pre-treated with the crude extract in pleurisy induced by carrageenan showed a reduction in the amounts of exudate, in the numbers of leukocytes and polymorphonuclear cells. Intragastric administration of the extract for seven days prior to the APAP-induced lesion showed no protective effect on the liver. The treatment with the extract induced an increase of serum aspartate aminotransferase, indicating a rise of toxicity. Contrarily, the same treatment reduced the APAP induced lesion in kidney, with respect to ν-glutamyltransferase. The results suggested that the extract was not hepatoprotective and could lead to an increase in the lesions induced by the APAP. On the other hand, the extract was nephroprotective against the lesions induced by the APAP and showed an anti-inflammatory effect on pleurisy carrageenan-induced.
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Radiation- induced aneuploidy in mammalian germ cells
International Nuclear Information System (INIS)
Tease, C.
1989-01-01
The ability of ionizing radiation to induce aneuploidy in mammalian germ cells has been investigated experimentally in the laboratory mouse using a variety of cytogenetic and genetic methods. These studies have provided unambiguous evidence of induced nondisjunction in both male and female germ cells when the effect of irradiation is screened in meiotic cells or preimplantation embryos. In contrast, however, cytogenetic analyses of post-implantation embryos and genetic assays for induced chromosome gains have not found a significant radiation effect. These apparently contradictory findings may be reconciled if (a) radiation induces tertiary rather than primary trisomy, or (b) induces embryo-lethal genetic damage, such as deletions, in addition to numerical anomalies. Either or both of these explanations may account for the apparent loss during gestation of radiation-induced trisomic embryos. Extrapolating from the information so far available, it seems unlikely that environmental exposure to low doses if low dose rate radiation will result in a detectable increase in the rate of aneuploidy in the human population. (author)
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Exercise-induced rhabdomyolysis.
Lee, George
2014-11-03
Exercise-induced rhabdomyolysis, or exertional rhabdomyolysis (ER), is a clinical entity typically considered when someone presents with muscle stiffness, swelling, and pain out of proportion to the expected fatigue post exercise. The diagnosis is confirmed by myoglobinuria, and an elevated serum Creatinine Phosphokinase (CPK) level, usually 10 times the normal range. However, an elevation in CPK is seen in most forms of strenuous exercise, up to 20 times the upper normal range. Therefore, there is no definitive pathologic CPK cut-off. Fortunately the dreaded complication of acute renal failure is rare compared to other forms rhabdomyolysis. We review the risks, diagnosis, clinical course and treatment for exercise- induced rhabdomyolysis.
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Sociocultural determinants of induced abortion
International Nuclear Information System (INIS)
Korejo, R.; Noorani, K.J.; Bhutta, S.
2003-01-01
Objective: To determine the frequency of induced abortion and identity the role of sociocultural factors contributing to termination of pregnancy and associated morbidity and mortality in hospital setting. Subjects and Methods: The patients who were admitted for induced abortion were interviewed in privacy. On condition of anonymity they were asked about the age, parity, family setup and relationships, with particular emphasis on sociocultural reasons and factors contributing to induction of abortion. Details of status of abortionist and methods used for termination of pregnancy, the resulting complications and their severity were recorded. Results: Out of total admissions, 57(2.35%) gave history of induced abortion. All women belonged to low socioeconomic class and 59.6% of them were illiterate. Forty-three (75.5%) of these women had never practiced concentration. Twenty-four (42%) were grandmultiparae and did not want more children. In 29 women (50.9%) the decision for abortion had been supported by the husband. In 25 (43.8%) abortion was carried out by Daiyan (traditional midwives). Serious complications like uterine perforation with or without bowel injury were encouraged in 25 (43.8%) of these women. During the study period illegally induced abortion accounted for 6 (10.5%) maternal deaths. Conclusion: Prevalence of poverty, illiteracy, grand multiparity and non-practice of contraception are strong determinants of induced abortion. (author)
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Infrared laser-induced chemical reactions
International Nuclear Information System (INIS)
Katayama, Mikio
1978-01-01
The experimental means which clearly distinguishes between infrared ray-induced reactions and thermal reactions has been furnished for the first time when an intense monochromatic light source has been obtained by the development of infrared laser. Consequently, infrared laser-induced chemical reactions have started to develop as one field of chemical reaction researches. Researches of laser-induced chemical reactions have become new means for the researches of chemical reactions since they were highlighted as a new promising technique for isotope separation. Specifically, since the success has been reported in 235 U separation using laser in 1974, comparison of this method with conventional separation techniques from the economic point of view has been conducted, and it was estimated by some people that the laser isotope separation is cheaper. This report briefly describes on the excitation of oscillation and reaction rate, and introduces the chemical reactions induced by CW laser and TEA CO 2 laser. Dependence of reaction yield on laser power, measurement of the absorbed quantity of infrared ray and excitation mechanism are explained. Next, isomerizing reactions are reported, and finally, isotope separation is explained. It was found that infrared laser-induced chemical reactions have the selectivity for isotopes. Since it is evident that there are many examples different from thermal and photo-chemical reactions, future collection of the data is expected. (Wakatsuki, Y.)
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Radiation-induced bone neoplasma in facial cranium
Energy Technology Data Exchange (ETDEWEB)
Zomer-Drozda, J; Buraczewska-Lipinska, H; Buraczewski, J [Instytut Onkologii, Warsaw (Poland)
1976-01-01
Radiation-induced bone neoplasms in the region of facial cranium account for about 40% of all radiation-induced tumours of bones, although the number of cases with lesions irradiated in this area is proportionally much lower than the number of cases treated with radiotherapy in other parts of the body. Four personal cases of radiation-induced tumours with complicated course are reported. Attention is called to the value of radiological investigations in the diagnosis of bone diseases and in differential diagnosis of radiation-induced tumours of bones.
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International Nuclear Information System (INIS)
Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin
2015-01-01
In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [de
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Inducing magneto-electric response in topological insulator
International Nuclear Information System (INIS)
Zeng, Lunwu; Song, Runxia; Zeng, Jing
2013-01-01
Utilizing electric potential and magnetic scalar potential formulas, which contain zero-order Bessel functions of the first kind and the constitutive relations of topological insulators, we obtained the induced magnetic scalar potentials and induced magnetic monopole charges which are induced by a point charge in topological insulators. The results show that infinite image magnetic monopole charges are generated by a point electric charge. The magnitude of the induced magnetic monopole charges are determined not only by the point electric charge, but also by the material parameters. - Highlights: ► Electric potential and magnetic scalar potential which contain zero-order Bessel function of the first kind were derived. ► Boundary conditions of topological insulator were built. ► Induced monopole charges were worked out.
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Tsunami Induced Scour Around Monopile Foundations
DEFF Research Database (Denmark)
Fuhrman, David R.; Eltard-Larsen, Bjarke; Baykal, Cüneyt
While the run-up, inundation, and destructive potential of tsunami events has received considerable attention in the literature, the associated interaction with the sea bed i.e. boundary layer dynamics, induced sediment transport, and resultant sea bed morphology, has received relatively little...... specific attention. The present paper aims to further the understanding of tsunami-induced scour, by numerically investigating tsunami-induced flow and scour processes around a monopile structure, representative of those commonly utilized as offshore wind turbine foundations. The simulations are based...... a monopile at model (laboratory) spatial and temporal scales. Therefore, prior to conducting such numerical simulations involving tsunami-induced scour, it is necessary to first establish a methodology for maintaining similarity of model and full field scales. To achieve hydrodynamic similarity we...
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Lin, Jia-Hui; Tseng, Wei-Lung
2015-01-01
Detection of salt- and analyte-induced aggregation of gold nanoparticles (AuNPs) mostly relies on costly and bulky analytical instruments. To response this drawback, a portable, miniaturized, sensitive, and cost-effective detection technique is urgently required for rapid field detection and monitoring of target analyte via the use of AuNP-based sensor. This study combined a miniaturized spectrometer with a 532-nm laser to develop a laser-induced Rayleigh scattering technique, allowing the sensitive and selective detection of Rayleigh scattering from the aggregated AuNPs. Three AuNP-based sensing systems, including salt-, thiol- and metal ion-induced aggregation of the AuNPs, were performed to examine the sensitivity of laser-induced Rayleigh scattering technique. Salt-, thiol-, and metal ion-promoted NP aggregation were exemplified by the use of aptamer-adsorbed, fluorosurfactant-stabilized, and gallic acid-capped AuNPs for probing K(+), S-adenosylhomocysteine hydrolase-induced hydrolysis of S-adenosylhomocysteine, and Pb(2+), in sequence. Compared to the reported methods for monitoring the aggregated AuNPs, the proposed system provided distinct advantages of sensitivity. Laser-induced Rayleigh scattering technique was improved to be convenient, cheap, and portable by replacing a diode laser and a miniaturized spectrometer with a laser pointer and a smart-phone. Using this smart-phone-based detection platform, we can determine whether or not the Pb(2+) concentration exceed the maximum allowable level of Pb(2+) in drinking water. Copyright © 2014 Elsevier B.V. All rights reserved.
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Mechanisms of caffeine-induced inhibition of UVB carcinogenesis
Directory of Open Access Journals (Sweden)
Allan H Conney
2013-06-01
Full Text Available Sunlight-induced nonmelanoma skin cancer is the most prevalent cancer in the United States with more than 2 million cases per year. Several studies have shown an inhibitory effect of caffeine administration on UVB-induced skin cancer in mice, and these studies are paralleled by epidemiology studies that indicate an inhibitory effect of coffee drinking on nonmelanoma skin cancer in humans. Strikingly, decaffeinated coffee consumption had no such inhibitory effect.Mechanism studies indicate that caffeine has a sunscreen effect that inhibits UVB-induced formation of thymine dimers and sunburn lesions in the epidermis of mice. In addition, caffeine administration has a biological effect that enhances UVB-induced apoptosis thereby enhancing the elimination of damaged precancerous cells, and caffeine administration also enhances apoptosis in tumors. Caffeine administration enhances UVB-induced apoptosis by p53-dependent and p53-independent mechanisms. Exploration of the p53-independent effect indicated that caffeine administration enhanced UVB-induced apoptosis by inhibiting the UVB-induced increase in ATR-mediated formation of phospho-Chk1 (Ser345 and abolishing the UVB-induced decrease in cyclin B1 which resulted in caffeine-induced premature and lethal mitosis in mouse skin. In studies with cultured primary human keratinocytes, inhibition of ATR with siRNA against ATR inhibited Chk1 phosphorylation and enhanced UVB-induced apoptosis. Transgenic mice with decreased epidermal ATR function that were irradiated chronically with UVB had 69% fewer tumors at the end of the study compared with irradiated littermate controls with normal ATR function. These results, which indicate that genetic inhibition of ATR (like pharmacologic inhibition of ATR via caffeine inhibits UVB-induced carcinogenesis and supports the concept that ATR-mediated phosphorylation of Chk1 is an important target for caffeine’s inhibitory effect on UVB-induced carcinogenesis.
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Reza, Musarrat Maisha; Subramaniyam, Nathiya; Sim, Chu Ming; Ge, Xiaojia; Sathiakumar, Durgalakshmi; McFarlane, Craig; Sharma, Mridula; Kambadur, Ravi
2017-10-24
Exercise induces expression of the myokine irisin, which is known to promote browning of white adipose tissue and has been shown to mediate beneficial effects following exercise. Here we show that irisin induces expression of a number of pro-myogenic and exercise response genes in myotubes. Irisin increases myogenic differentiation and myoblast fusion via activation of IL6 signaling. Injection of irisin in mice induces significant hypertrophy and enhances grip strength of uninjured muscle. Following skeletal muscle injury, irisin injection improves regeneration and induces hypertrophy. The effects of irisin on hypertrophy are due to activation of satellite cells and enhanced protein synthesis. In addition, irisin injection rescues loss of skeletal muscle mass following denervation by enhancing satellite cell activation and reducing protein degradation. These data suggest that irisin functions as a pro-myogenic factor in mice.
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Apoptosis inducing factor (AIF) mediates lethal redox stress induced by menadione.
Wiraswati, Hesti Lina; Hangen, Emilie; Sanz, Ana Belén; Lam, Ngoc-Vy; Reinhardt, Camille; Sauvat, Allan; Mogha, Ariane; Ortiz, Alberto; Kroemer, Guido; Modjtahedi, Nazanine
2016-11-22
Mitochondrial apoptosis inducing factor (AIF) is a redox-active enzyme that participates to the biogenesis/maintenance of complex I of the respiratory chain, yet also contributes to catabolic reactions in the context of regulated cell death when AIF translocates to the cytosol and to the nucleus. Here we explore the contribution of AIF to cell death induced by menadione (2-methyl-1,4-naphtoquinone; also called vitamin K3) in conditions in which this pro-oxidant does not cause the mitochondrial release of AIF, yet causes caspase-independent cell killing. Depletion of AIF from human cancer cells reduced the cytotoxicity of menadione. This cytoprotective effect was accompanied by the maintenance of high levels of reduced glutathione (GSH), which are normally depleted by menadione. In addition, AIF depletion reduced the arylation of cellular proteins induced by menadione. This menadione-triggered arylation, which can be measured by a fluorescence assay, is completely suppressed by addition of exogenous glutathione or N-acetyl cysteine. Complex I inhibition by Rotenone did not mimic the cytoprotective action of AIF depletion. Altogether, these results are compatible with the hypothesis that mitochondrion-sessile AIF facilitates lethal redox cycling of menadione, thereby precipitating protein arylation and glutathione depletion.
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AMPHIBIAN COMMUNITIES IN BIOGEOCOENOSIS WITH DIFFERENT STAGES OF ANTHROPOGENIC CLYMAX
Directory of Open Access Journals (Sweden)
Marchenkovskaya А. А.
2013-04-01
Full Text Available We examined the abundance of juvenile (fingerlings and yearlings and sexually mature (3-6 years of various anurans at various biotopes with different degrees of anthropogenic influence. Population analysis has revealed that the number of juveniles in all the habitats are depended on type and level of anthropogenic influence. In all the habitats the most numerous species was synanthropic bufo viridis. In biotopes with high contamination of pollutants, only one species of amphibians - the marsh frog has populations with juveniles migrating here in the early fall. The highest number of mature individuals registered for the population of Bombina bombina, pelobates fuscus and in one biotope for hyla arborea. The populations of pelophylax ridibundus could be considered as the most balanced by number of juvenile and mature individuals.
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Blood parasites of amphibians from Sichuan Province, People's Republic of China.
Werner, J K
1993-06-01
Two hundred forty-six amphibians from Sichuan Province, People's Republic of China, were examined for blood parasites between April and June 1990. Six trypanosome species were found, 2 of which were not identified because of poor material. Trypanosoma rotatorium (sensu Mayer, 1843) was found in Rana limnocharis and Rana nigromaculata. Trypanosoma chattoni and a T. rotatorium-like species were found in Bufo gargarizans. A sphaeromastigote similar to Trypanosoma tsunezomiyatai was seen in R. limnocharis. The relationship of this parasite to T. chattoni is unclear. Dactylosoma ranarum, Lankesterella minima, and Aegyptianella bacterifera were identified in ranids. Frog erythrocytic virus (FEV) was found in 2 ranids and a bufonid. Differences in shape of FEV and its assumed effect on the host-cell nucleus suggest that different kinds of viruses may be involved.
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Christensen, Pernille; Thomsen, Simon Francis; Rasmussen, Niels; Backer, Vibeke
2007-11-19
Recent studies suggest that exercise-induced inspiratory stridor (EIIS) is an important and often overlooked differential diagnosis of exercise-induced asthma. EIIS is characterised by astma-like symptoms, but differs by inspiratory limitation, fast recovery, and a lack of effect of inhaled bronchodilators. The prevalence of EIIS is reported to be 5-27%, and affects both children and adults. The pathophysiology, the pathogenesis, and the treatment of the condition are not yet clarified. At present, a population-based study is being conducted in order to address these points.
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ETHICS IN HEALTH CARE: INDUCEMENT AND HUMAN SUBJECTS
Directory of Open Access Journals (Sweden)
MUNIR HOSSAIN TALUKDER
2011-05-01
Full Text Available Currently, most health researchers or donor organizations considerinducement as a vital part in promoting research. They propose benefits, such as post research free medical treatment, food, insurance facilities, or even cash, in order to meet sufficient number of subjects. So, inducement may influence one to participate in a research. Is it ethical to offer inducement to human subjects? What are the risks in such practice? What will happen if the donor agencies use subjects by hiding possible risks from them? When an inducement can satisfy ethical criteria? The CIOMS, FDA, and other ethical guidelines hold that inducement is unethical because it involves enough risk for voluntary informed consent. Supporting this position, a group of ethicists has argued that inducement undermines voluntariness especially when subjects are poor and vulnerable, and thus, unethical. In contrast to them, others argue that inducement contributes to discover new knowledge which can improve miserable condition of the poor. In their view, an inducement maintains all ethical criteria including subject’s autonomy, and therefore, morally permissible. The paper focuses this debate and analyzes both types ofargument. It examines whether inducement invalidate informed consent.Even if inducement may not violate the basic components of informedconsent, the paper concludes, subjects may claim a prima facie right to enjoy research outcomes.
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Gu, Ruiping; Tang, Wenyi; Lei, Boya; Ding, Xinyi; Jiang, Cheng; Xu, Gezhi
2017-07-01
The aim of the present study was to investigate the neuroprotective effects of glucocorticoid-induced leucine zipper (GILZ) in a light-induced retinal degeneration model and to explore the underlying mechanisms. Intravitreal injection of recombinant GILZ-overexpressing lentivirus (OE-GILZ-rLV) and short hairpin RNA targeting GILZ recombinant lentivirus (shRNA-GILZ-rLV) was performed to up- and downregulate retinal GILZ, respectively. Three days after stable transduction, rats were exposed to continuous bright light (5000 lux) for 2 days. Retinal function was assessed by full-field electroretinography (ERG), and the retinal structure was examined for photoreceptor survival and death in rats kept under a 12-hour light:2-hour dark cycle following light exposure. The expression levels of retinal Bcl-xL, caspase-9, and caspase-3 were examined by Western blotting or real-time PCR at 1, 3, 5, and 7 days after light exposure. Exposure to bright light downregulated retinal GILZ in parallel with the downregulation of Bcl-xL and the upregulation of active caspase-3. Overexpression of retinal GILZ attenuated the decrease of Bcl-xL and the activation of caspase-9 and caspase-3 at 1, 3, 5, and 7 days after bright light exposure, respectively. GILZ silencing aggravated the downregulation of Bcl-xL induced by bright light exposure. Bright light exposure reduced the amplitude of ERG, increased the number of apoptotic photoreceptor cells, and decreased retinal thickness; and GILZ overexpression could attenuate all these effects. Overexpression of GILZ by OE-GILZ-rLV transduction protected the retina from light-induced cellular damage by activating antiapoptotic pathways.
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Agmatine attenuates silica-induced pulmonary fibrosis.
El-Agamy, D S; Sharawy, M H; Ammar, E M
2014-06-01
There is a large body of evidence that nitric oxide (NO) formation is implicated in mediating silica-induced pulmonary fibrosis. As a reactive free radical, NO may not only contribute to lung parenchymal tissue injury but also has the ability to combine with superoxide and form a highly reactive toxic species peroxynitrite that can induce extensive cellular toxicity in the lung tissues. This study aimed to explore the effect of agmatine, a known NO synthase inhibitor, on silica-induced pulmonary fibrosis in rats. Male Sprague Dawley rats were treated with agmatine for 60 days following a single intranasal instillation of silica suspension (50 mg in 0.1 ml saline/rat). The results revealed that agmatine attenuated silica-induced lung inflammation as it decreased the lung wet/dry weight ratio, protein concentration, and the accumulation of the inflammatory cells in the bronchoalveolar lavage fluid. Agmatine showed antifibrotic activity as it decreased total hydroxyproline content of the lung and reduced silica-mediated lung inflammation and fibrosis in lung histopathological specimen. In addition, agmatine significantly increased superoxide dismutase (p Agmatine also reduced silica-induced overproduction of pulmonary nitrite/nitrate as well as tumor necrosis factor α. Collectively, these results demonstrate the protective effects of agmatine against the silica-induced lung fibrosis that may be attributed to its ability to counteract the NO production, lipid peroxidation, and regulate cytokine effects. © The Author(s) 2014.
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The Effects of Acute Stress-Induced Sleep Disturbance on Acoustic Trauma-Induced Tinnitus in Rats
Directory of Open Access Journals (Sweden)
Yiwen Zheng
2014-01-01
Full Text Available Chronic tinnitus is a debilitating condition and often accompanied by anxiety, depression, and sleep disturbance. It has been suggested that sleep disturbance, such as insomnia, may be a risk factor/predictor for tinnitus-related distress and the two conditions may share common neurobiological mechanisms. This study investigated whether acute stress-induced sleep disturbance could increase the susceptibility to acoustic trauma-induced tinnitus in rats. The animals were exposed to unilateral acoustic trauma 24 h before sleep disturbance being induced using the cage exchange method. Tinnitus perception was assessed behaviourally using a conditioned lick suppression paradigm 3 weeks after the acoustic trauma. Changes in the orexin system in the hypothalamus, which plays an important role in maintaining long-lasting arousal, were also examined using immunohistochemistry. Cage exchange resulted in a significant reduction in the number of sleep episodes and acoustic trauma-induced tinnitus with acoustic features similar to a 32 kHz tone at 100 dB. However, sleep disturbance did not exacerbate the perception of tinnitus in rats. Neither tinnitus alone nor tinnitus plus sleep disturbance altered the number of orexin-expressing neurons. The results suggest that acute sleep disturbance does not cause long-term changes in the number of orexin neurons and does not change the perception of tinnitus induced by acoustic trauma in rats.
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Collagen-induced arthritis in mice
Bevaart, Lisette; Vervoordeldonk, Margriet J.; Tak, Paul P.
2010-01-01
Collagen-induced arthritis (CIA) in mice is an animal model for rheumatoid arthritis (RA) and can be induced in DBA/1 and C57BL/6 mice using different protocols. The CIA model can be used to unravel mechanisms involved in the development of arthritis and is frequently used to study the effect of new
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X-irradiation-induced emesis in Suncus murinus
International Nuclear Information System (INIS)
Torii, Yoshifumi; Saito, Hiroshi; Matsuki, Norio; Shikita, Mikio.
1993-01-01
X-irradiation-induced emesis was investigated in Suncus murinus, a house musk shrew. Whole body X-irradiation caused emesis, and the calculated ED 50 value that induced emesis in 50% of animals was 429 cGy. At the irradiation dose of 800 cGy all the animals vomited 10.0±2.4 times with a latency of 20.0±2.9 min. The emetogenic effect of X-irradiation was dependent on the part of the body exposed. Abdominal X-irradiation at 1000 cGy caused emesis in all animals studied, whereas the same dose to the head had no emetogenic effect. We investigated several prophylactic methods against X-irradiation-induced emesis. Surgical vagotomy completely inhibited the emesis induced by 800 cGy X-irradiation. Emesis was also prevented by the subcutaneous administration of tropisetron (ICS 205-930, a selective serotonergic 5-HT 3 receptor antagonist) with an ID 50 value of 29 μg/kg. These results suggest that (1) suncus is a useful experimental animal for the study of radiation-induced emesis and the development of prophylactic drugs, (2) serotonin plays an important role in X-irradiation-induced emesis, and (3) X-irradiation-induced emesis is very similar to that caused by cancer chemotherapeutic agents. (author)
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Impact of mechanical stress induced in silica vacuum windows on laser-induced damage.
Gingreau, Clémence; Lanternier, Thomas; Lamaignère, Laurent; Donval, Thierry; Courchinoux, Roger; Leymarie, Christophe; Néauport, Jérôme
2018-04-15
At the interface between vacuum and air, optical windows must keep their optical properties, despite being subjected to mechanical stress. In this Letter, we investigate the impact of such stress on the laser-induced damage of fused silica windows at the wavelength of 351 nm in the nanosecond regime. Different stress values, from 1 to 30 MPa, both tensile and compressive, were applied. No effect of the stress on the laser-induced damage was evidenced.
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RMP-Flutter-Induced Pedestal Plasma Transport
Energy Technology Data Exchange (ETDEWEB)
Callen, J. D.; Hegna, C., E-mail: callen@engr.wisc.edu [University of Wisconsin, Madison (United States); Cole, A. J. [Columbia University, New York (United States)
2012-09-15
Full text: Plasma toroidal rotation can prevent or limit reconnection of externally applied resonant magnetic perturbation (RMP) fields {delta}B on rational magnetic flux surfaces. Hence, it causes the induced radial perturbations to vanish or be small there, and thereby inhibits magnetic island formation and stochasticity in the edge of high (H-mode) confinement tokamak plasmas. However, the radial component of the spatial magnetic flutter induced by RMP fields off rational surfaces causes a radial electron thermal diffusivity of (1/2)({delta}B{sub p}/B){sup 2} times a magnetic-shear-influenced effective parallel electron thermal diffusivity. The resultant RMP-flutter-induced electron thermal diffusivity can be comparable to experimentally inferred values at the top of H-mode pedestals. This process also causes a factor of about 3 smaller RMP-induced electron density diffusivity there. Because this electron density transport is non-ambipolar, it produces a toroidal torque on the plasma, which is usually in the co-current direction. Kinetic-based cylindrical screw-pinch and toroidal models of these RMP-flutter-induced plasma transport effects have been developed. The RMP-induced increases in these diffusive plasma transport processes are typically spatially inhomogeneous in that they are strongly peaked near the rational surfaces in low collisionality pedestals, which may lead to resonant sensitivities to the local safety factor q. The effects can be large enough to reduce the radially averaged gradients of the electron temperature and density at the top of H-mode edge pedestals, and modify the plasma toroidal rotation and radial electric field there. At high collisionality the various effects are less strongly peaked at rational surfaces and thus less likely to exhibit RMP-induced resonant behavior. These RMP-flutter-induced plasma transport processes provide a new paradigm for developing an understanding of how RMPs modify the pedestal structure to stabilize
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Directory of Open Access Journals (Sweden)
Jennifer M Curry
Full Text Available BACKGROUND: M-CSF recruits mononuclear phagocytes which regulate processes such as angiogenesis and metastases in tumors. VEGF is a potent activator of angiogenesis as it promotes endothelial cell proliferation and new blood vessel formation. Previously, we reported that in vitro M-CSF induces the expression of biologically-active VEGF from human monocytes. METHODOLOGY AND RESULTS: In this study, we demonstrate the molecular mechanism of M-CSF-induced VEGF production. Using a construct containing the VEGF promoter linked to a luciferase reporter, we found that a mutation reducing HIF binding to the VEGF promoter had no significant effect on luciferase production induced by M-CSF stimulation. Further analysis revealed that M-CSF induced VEGF through the MAPK/ERK signaling pathway via the transcription factor, Sp1. Thus, inhibition of either ERK or Sp1 suppressed M-CSF-induced VEGF at the mRNA and protein level. M-CSF also induced the nuclear localization of Sp1, which was blocked by ERK inhibition. Finally, mutating the Sp1 binding sites within the VEGF promoter or inhibiting ERK decreased VEGF promoter activity in M-CSF-treated human monocytes. To evaluate the biological significance of M-CSF induced VEGF production, we used an in vivo angiogenesis model to illustrate the ability of M-CSF to recruit mononuclear phagocytes, increase VEGF levels, and enhance angiogenesis. Importantly, the addition of a neutralizing VEGF antibody abolished M-CSF-induced blood vessel formation. CONCLUSION: These data delineate an ERK- and Sp1-dependent mechanism of M-CSF induced VEGF production and demonstrate for the first time the ability of M-CSF to induce angiogenesis via VEGF in vivo.
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Inducing magneto-electric response in topological insulator
Energy Technology Data Exchange (ETDEWEB)
Zeng, Lunwu, E-mail: 163.sin@163.com [Jiangsu Key Laboratory for Intelligent Agricultural Equipment, College of Engineering, Nanjing Agricultural University, Nanjing 210031 (China); Song, Runxia [Jiangsu Key Laboratory for Intelligent Agricultural Equipment, College of Engineering, Nanjing Agricultural University, Nanjing 210031 (China); Zeng, Jing [Faculty of Business and Economics, Macquarie University, NSW 2122 (Australia)
2013-02-15
Utilizing electric potential and magnetic scalar potential formulas, which contain zero-order Bessel functions of the first kind and the constitutive relations of topological insulators, we obtained the induced magnetic scalar potentials and induced magnetic monopole charges which are induced by a point charge in topological insulators. The results show that infinite image magnetic monopole charges are generated by a point electric charge. The magnitude of the induced magnetic monopole charges are determined not only by the point electric charge, but also by the material parameters. - Highlights: Black-Right-Pointing-Pointer Electric potential and magnetic scalar potential which contain zero-order Bessel function of the first kind were derived. Black-Right-Pointing-Pointer Boundary conditions of topological insulator were built. Black-Right-Pointing-Pointer Induced monopole charges were worked out.
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Inducing Lactation: Breastfeeding for Adoptive Moms
... Dynamics > Adoption & Foster Care > Inducing Lactation: Breastfeeding for Adoptive Moms Family Life Listen Español Text Size Email Print Share Inducing Lactation: Breastfeeding for Adoptive Moms Page Content Article Body A growing number ...
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Energy Technology Data Exchange (ETDEWEB)
Kim, Hyung Gyun [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of); Han, Eun Hee [Division of Life Science, Korea Basic Science Institute, Daejeon (Korea, Republic of); Im, Ji Hye; Lee, Eun Ji; Jin, Sun Woo [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of); Jeong, Hye Gwang, E-mail: hgjeong@cnu.ac.kr [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon (Korea, Republic of)
2015-09-25
Caffeic acid phenethyl ester (CAPE), a natural component of propolis, is reported to have anticarcinogenic properties, although its precise chemopreventive mechanism remains unclear. In this study, we examined the effects of CAPE on 3-methylcholanthrene (3-MC)-induced CYP1A1 expression and activities. CAPE reduced the formation of the benzo[a]pyrene-DNA adduct. Moreover, CAPE inhibited 3-MC-induced CYP1A1 activity, mRNA expression, protein level, and promoter activity. CAPE treatment also decreased 3-MC-inducible xenobiotic-response element (XRE)-linked luciferase, aryl hydrocarbons receptor (AhR) transactivation and nuclear localization. CAPE induced hypoxia inducible factor-1α (HIF-1α) protein level and HIF-1α responsible element (HRE) transcriptional activity. CAPE-mediated HIF-1α reduced 3-MC-inducible CYP1A1 protein expression. Taken together, CAPE decreases 3-MC-mediated CYP1A1 expression, and this inhibitory response is associated with inhibition of AhR and HIF-1α induction. - Highlights: • CAPE reduced the formation of the benzo[a]pyrene-DNA adduct. • CAPE inhibited 3-MC-induced CYP1A1 expression. • CAPE induced HIF-1α induction. • CAPE-mediated HIF-1α reduced 3-MC-inducible CYP1A1 expression.
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Induced pluripotent stem cell-derived neurons as a human model for testing environmentally induced developmental neurotoxicity Ingrid L. Druwe1, Timothy J. Shafer2, Kathleen Wallace2, Pablo Valdivia3 ,and William R. Mundy2. 1University of North Carolina, Curriculum in Toxicology...
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El-Kader, M. S. A.; Godet, J.-L.; Gustafsson, M.; Maroulis, G.
2018-04-01
Quantum mechanical lineshapes of collision-induced absorption (CIA), collision-induced light scattering (CILS) and collision-induced hyper-Rayleigh scattering (CIHR) at room temperature (295 K) are computed for gaseous mixtures of molecular hydrogen with neon, krypton and xenon. The induced spectra are detected using theoretical values for induced dipole moment, pair-polarizability trace and anisotropy, hyper-polarizability and updated intermolecular potentials. Good agreement is observed for all spectra when the literature and the present potentials which are constructed from the transport and thermo-physical properties are used.
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International Nuclear Information System (INIS)
Han, Jeongoh; Lee, Jong-Suk; Choi, Daekyu; Lee, Youna; Hong, Sungchae; Choi, Jungyun; Han, Songyi; Ko, Yujin; Kim, Jung-Ae; Mi Kim, Young; Jung, Yunjin
2009-01-01
Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1α protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1α hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1α degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1α protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines. The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation
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Smina, T P; Mathew, J; Janardhanan, K K
2016-04-30
G. lucidum total triterpenes were assessed for its apoptosis-inducing and anti-tumour activities. The ability of the total triterpenes to induce apoptosis was evaluated in Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines. Total triterpenes were found to be highly cytotoxic to DLA and EAC cell lines with IC50 values 5 ± 0.32 and 7.9 ± 0.2 µg/ml respectively. Total triterpenes induced apoptosis in both cell lines which is evident from the DNA fragmentation assay. Anti-tumour activity was accessed using DLA induced solid and EAC induced ascites tumour models in Swiss albino mice. Administration of 10, 50 and 100 mg/kg b. wt. total triterpenes showed 11.86, 27.27 and 40.57% increase in life span of animals in ascites tumour model. Treatment with 10, 50 and 100 mg/kg b. wt. total triterpenes exhibited 76.86, 85.01 and 91.03% inhibition in tumour volume and 67.96, 72.38 and 77.90% inhibition in tumour weight respectively in the solid tumour model. The study reveals the significant dose-dependent anti-tumour activity of total triterpenes in both models. Total triterpenes were more active against the solid tumour than the ascites tumour. The anti-oxidant potential and ability to induce cell-specific apoptosis could be contributing to its anti-tumour activities.
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Hydroxychloroquine-induced erythroderma.
Pai, Sunil B; Sudershan, Bhuvaneshwari; Kuruvilla, Maria; Kamath, Ashwin; Suresh, Pooja K
2017-01-01
Erythroderma is characterized by diffuse erythema and scaling of the skin involving more than 90% of the total body skin surface area. Drug-induced erythroderma has rarely been reported with hydroxychloroquine. We report a case of a 50-year-old female patient, with systemic lupus erythematosus, who developed itchy lesions all over the body 1 month after starting treatment with hydroxychloroquine. Drug-induced erythroderma was suspected. Hydroxychloroquine was withdrawn and the patient was treated with emollients, mid-potency corticosteroids, and oral antihistamines. A biopsy was done which confirmed the diagnosis of erythroderma. She recovered with treatment and was discharged. A careful history and clinical examination to search for potential causative factors will help prevent disabling sequelae in erythroderma.
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Energy Technology Data Exchange (ETDEWEB)
Wang, Xin; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, Shanghai, China 201203 (China); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, Shanghai, China 201203 (China)
2017-04-01
Thiamine (vitamin B1) deficiency (TD) plays a major role in the etiology of Wernicke's encephalopathy (WE) which is a severe neurological disorder. TD induces selective neuronal cell death, neuroinflammation, endoplasmic reticulum (ER) stress and oxidative stress in the brain which are commonly observed in many aging-related neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and progressive supranuclear palsy (PSP). However, the underlying cellular and molecular mechanisms remain unclear. The progress in this line of research is hindered due to the lack of appropriate in vitro models. The neurons derived for the human induced pluripotent stem cells (hiPSCs) provide a relevant and powerful tool for the research in pharmaceutical and environmental neurotoxicity. In this study, we for the first time used human induced pluripotent stem cells (hiPSCs)-derived neurons (iCell neurons) to investigate the mechanisms of TD-induced neurodegeneration. We showed that TD caused a concentration- and duration-dependent death of iCell neurons. TD induced ER stress which was evident by the increase in ER stress markers, such as GRP78, XBP-1, CHOP, ATF-6, phosphorylated eIF2α, and cleaved caspase-12. TD also triggered oxidative stress which was shown by the increase in the expression 2,4-dinitrophenyl (DNP) and 4-hydroxynonenal (HNE). ER stress inhibitors (STF-083010 and salubrinal) and antioxidant N-acetyl cysteine (NAC) were effective in alleviating TD-induced death of iCell neurons, supporting the involvement of ER stress and oxidative stress. It establishes that the iCell neurons are a novel tool to investigate cellular and molecular mechanisms for TD-induced neurodegeneration. - Highlights: • Thiamine deficiency (TD) causes death of human neurons in culture. • TD induces both endoplasmic reticulum (ER) stress and oxidative stress. • Alleviating ER stress and oxidative stress reduces TD-induced
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International Nuclear Information System (INIS)
Wang, Xin; Xu, Mei; Frank, Jacqueline A.; Ke, Zun-ji; Luo, Jia
2017-01-01
Thiamine (vitamin B1) deficiency (TD) plays a major role in the etiology of Wernicke's encephalopathy (WE) which is a severe neurological disorder. TD induces selective neuronal cell death, neuroinflammation, endoplasmic reticulum (ER) stress and oxidative stress in the brain which are commonly observed in many aging-related neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and progressive supranuclear palsy (PSP). However, the underlying cellular and molecular mechanisms remain unclear. The progress in this line of research is hindered due to the lack of appropriate in vitro models. The neurons derived for the human induced pluripotent stem cells (hiPSCs) provide a relevant and powerful tool for the research in pharmaceutical and environmental neurotoxicity. In this study, we for the first time used human induced pluripotent stem cells (hiPSCs)-derived neurons (iCell neurons) to investigate the mechanisms of TD-induced neurodegeneration. We showed that TD caused a concentration- and duration-dependent death of iCell neurons. TD induced ER stress which was evident by the increase in ER stress markers, such as GRP78, XBP-1, CHOP, ATF-6, phosphorylated eIF2α, and cleaved caspase-12. TD also triggered oxidative stress which was shown by the increase in the expression 2,4-dinitrophenyl (DNP) and 4-hydroxynonenal (HNE). ER stress inhibitors (STF-083010 and salubrinal) and antioxidant N-acetyl cysteine (NAC) were effective in alleviating TD-induced death of iCell neurons, supporting the involvement of ER stress and oxidative stress. It establishes that the iCell neurons are a novel tool to investigate cellular and molecular mechanisms for TD-induced neurodegeneration. - Highlights: • Thiamine deficiency (TD) causes death of human neurons in culture. • TD induces both endoplasmic reticulum (ER) stress and oxidative stress. • Alleviating ER stress and oxidative stress reduces TD-induced
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Directory of Open Access Journals (Sweden)
Min Zhang
2016-01-01
Full Text Available A rigid circular cylinder with two piezoelectric beams attached on has been tested through vortex-induced vibrations (VIV and wake-induced vibrations (WIV by installing a big cylinder fixed upstream, in order to study the influence of the different flow-induced vibrations (FIV types. The VIV test shows that the output voltage increases with the increases of load resistance; an optimal load resistance exists for the maximum output power. The WIV test shows that the vibration of the small cylinder is controlled by the vortex frequency of the large one. There is an optimal gap of the cylinders that can obtain the maximum output voltage and power. For a same energy harvesting device, WIV has higher power generation capacity; then the piezoelectric output characteristics can be effectively improved.
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Induced proteins in human melanomas by γ-ray
International Nuclear Information System (INIS)
Ohnishi, T.; Ihara, M.; Utsumi, H.
1992-01-01
When cells are exposed to environmental stresses such as heat, chemicals, radiation, the cells respond to them by synthesizing a characteristic group of proteins, called stress proteins. There are many famous stress proteins: heat shock proteins and metallothionein. Treated cells have a protective mechanism against these environmental stresses. SOS responses in Escherichia coli are most famous. As the mechanisms, when cells are exposed by many kinds of DNA damage agents, various enzymes are induced after the cleavage of repressor protein LexA by activated RecA enzyme. Thereafter, induced proteins act for DNA repair and mutagenesis. In mammalian cells there are many reports about inducible genes such as O 6 -methylguanine methyltransferase gene. This gene was also inducible by alkylating agents. The difference of radiation sensitivities may be reflected by the contents of repair enzymes(s) or the induced proteins. Therefore, this study aims on the differences in inducible proteins between radiosensitive cells and control cells. Since it was hypothesized that induced proteins concerning to DNA damage repair or the proteins to recognize the damage may exist in the nuclei, induced proteins in nuclei of γ-ray irradiated cells were analyzed. (author). 5 refs., 1 tab
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Overgaard, Johannes; Andersen, Jonas L; Findsen, Anders; Pedersen, Pil B M; Hansen, Kasper; Ozolina, Karlina; Wang, Tobias
2012-10-15
Numerous recent studies convincingly correlate the upper thermal tolerance limit of aquatic ectothermic animals to reduced aerobic scope, and ascribe the decline in aerobic scope to failure of the cardiovascular system at high temperatures. In the present study we investigate whether this 'aerobic scope model' applies to an air-breathing and semi-terrestrial vertebrate Rhinella marina (formerly Bufo marinus). To quantify aerobic scope, we measured resting and maximal rate of oxygen consumption at temperatures ranging from 10 to 40°C. To include potential effects of acclimation, three groups of toads were acclimated chronically at 20, 25 and 30°C, respectively. The absolute difference between resting and maximal rate of oxygen consumption increased progressively with temperature and there was no significant decrease in aerobic scope, even at temperature immediately below the lethal limit (41-42°C). Haematological and cardiorespiratory variables were measured at rest and immediately after maximal activity at benign (30°C) and critically high (40°C) temperatures. Within this temperature interval, both resting and active heart rate increased, and there was no indication of respiratory failure, judged from high arterial oxygen saturation, P(O2) and [Hb(O2)]. With the exception of elevated resting metabolic rate for cold-acclimated toads, we found few differences in the thermal responses between acclimation groups with regard to the cardiometabolic parameters. In conclusion, we found no evidence for temperature-induced cardiorespiratory failure in R. marina, indicating that maintenance of aerobic scope and oxygen transport is unrelated to the upper thermal limit of this air-breathing semi-terrestrial vertebrate.
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Molecular Mechanisms of Antipsychotic Drug-Induced Diabetes
Directory of Open Access Journals (Sweden)
Jiezhong Chen
2017-11-01
Full Text Available Antipsychotic drugs (APDs are widely prescribed to control various mental disorders. As mental disorders are chronic diseases, these drugs are often used over a life-time. However, APDs can cause serious glucometabolic side-effects including type 2 diabetes and hyperglycaemic emergency, leading to medication non-compliance. At present, there is no effective approach to overcome these side-effects. Understanding the mechanisms for APD-induced diabetes should be helpful in prevention and treatment of these side-effects of APDs and thus improve the clinical outcomes of APDs. In this review, the potential mechanisms for APD-induced diabetes are summarized so that novel approaches can be considered to relieve APD-induced diabetes. APD-induced diabetes could be mediated by multiple mechanisms: (1 APDs can inhibit the insulin signaling pathway in the target cells such as muscle cells, hepatocytes and adipocytes to cause insulin resistance; (2 APD-induced obesity can result in high levels of free fatty acids (FFA and inflammation, which can also cause insulin resistance. (3 APDs can cause direct damage to β-cells, leading to dysfunction and apoptosis of β-cells. A recent theory considers that both β-cell damage and insulin resistance are necessary factors for the development of diabetes. In high-fat diet-induced diabetes, the compensatory ability of β-cells is gradually damaged, while APDs cause direct β-cell damage, accounting for the severe form of APD-induced diabetes. Based on these mechanisms, effective prevention of APD-induced diabetes may need an integrated approach to combat various effects of APDs on multiple pathways.
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Sociocultural determinants of induced abortion.
Korejo, Razia; Noorani, Khurshid Jehan; Bhutta, Shereen
2003-05-01
To determine the frequency of induced abortion and identify the role of sociocultural factors contributing to termination of pregnancy and associated morbidity and mortality in hospital setting. Prospective observational study. The study was conducted in the Department of Obstetrics and Gynaecology, Jinnah Postgraduate Medical Centre, Karachi from January 1999 to June 2001. The patients who were admitted for induced abortion were interviewed in privacy. On condition of anonymity they were asked about the age, parity, family setup and relationships, with particular emphasis on sociocultural reasons and factors contributing to induction of abortion. Details of status of abortionist and methods used for termination of pregnancy, the resulting complications and their severity were recorded. Out of total admissions, 57(2.35%) gave history of induced abortion. All women belonged to low socioeconomic class and 59.6% of them were illiterate. Forty-three (75.5%) of these women had never practiced contraception. Twenty-four (42%) were grandmultiparae and did not want more children. In 29 women (50.9%) the decision for abortion had been supported by the husband. In 25 women (43.8%) abortion was carried out by Daiyan (traditional midwives). Serious complications like uterine perforation with or without bowel injury were encountered in 25 (43.8%) of these women. During the study period illegally induced abortion accounted for 6 (10.5%) maternal deaths. Prevalence of poverty, illiteracy, grand multiparity and non-practice of contraception are strong determinants of induced abortion.
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Directory of Open Access Journals (Sweden)
Nan He
2017-11-01
Full Text Available The rapid development of China’s railway has exerted an enormous influence on the intercity passenger transport structure in recent years. However, it has not satisfied the passengers’ travel demand due to induced traffic. This paper is committed to solving such issue, with the aim of satisfying the current travel demand, and of anticipating the demand of the predicted traffic growth over the next 20 to 30 years. The paper has considered the increase in rail passenger kilometres caused by the growth of rail kilometres as rail-induced traffic. Based on the concept and former research of induced traffic, the panel data of 26 provinces and 3 municipalities of China between the year 2000 and 2014 were collected, and the elasticity models (including elasticity-based model, distributed lag model, high-speed rail (HSR elasticity model and rail efficiency model have been constructed. The results show the importance of model formation incorporation of rail-induced traffic. It is better to get the correct value in divided zones with different train frequencies or incorporation rail efficiency in cities or provinces. The lag time and rail types also need to be considered. In summary, the results analysis not only confirms the existence of rail-induced traffic, but also provides substantial recommendations to train operation planning.
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Yoshioka, Yasuhiro; Kitao, Tatsuya; Kishino, Takashi; Yamamuro, Akiko; Maeda, Sadaaki
2006-04-15
We investigated the cytoprotective effect of NO on H2O2-induced cell death in mouse macrophage-like cell line RAW264. H2O2-treated cells showed apoptotic features, such as activation of caspase-9 and caspase-3, nuclear fragmentation, and DNA fragmentation. These apoptotic features were significantly inhibited by pretreatment for 24 h with NO donors, sodium nitroprusside and 1-hydroxy-2-oxo-3,3-bis-(2-aminoethyl)-1-triazene, at a low nontoxic concentration. The cytoprotective effect of NO was abrogated by the catalase inhibitor 3-amino-1,2,4-triazole but was not affected by a glutathione synthesis inhibitor, L-buthionine-(S,R)-sulfoximine. NO donors increased the level of catalase and its activity in a concentration-dependent manner. Cycloheximide, a protein synthesis inhibitor, inhibited both the NO-induced increase in the catalase level and the cytoprotective effect of NO. These results indicate that NO at a low concentration protects macrophages from H2O2-induced apoptosis by inducing the production of catalase.
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International Nuclear Information System (INIS)
Nakajima, Tetsuo; Yukawa, Osami; Tsuji, Hideo; Ohyama, Harumi; Wang, Bing; Tatsumi, Kouichi; Hayata, Isamu; Hama-Inaba, Hiroko
2006-01-01
Protein kinase Cδ (PKCδ) has an important role in radiation-induced apoptosis. The expression and function of PKCδ in radiation-induced apoptosis were assessed in a radiation-sensitive mouse thymic lymphoma cell line, 3SBH5, and its radioresistant variant, XR223. Rottlerin, a PKCδ-specific inhibitor, completely abolished radiation-induced apoptosis in 3SBH5. Radiation-induced PKCδ activation correlated with the degradation of PKCδ, indicating that PKCδ activation through degradation is involved in radiation-induced apoptosis in radiosensitive 3SBH5. In radioresistant XR223, radiation-induced PKCδ activation was lower than that in radiosensitive 3SBH5. Cytosol PKCδ levels in 3SBH5 decreased markedly after irradiation, while those in XR223 did not. There was no apparent change after irradiation in the membrane fractions of either cell type. In addition, basal cytosol PKCδ levels in XR223 were higher than those in 3SBH5. These results suggest that the radioresistance in XR223 to radiation-induced apoptosis is due to a difference in the regulation of radiation-induced PKCδ activation compared to that of 3SBH5. On the other hand, Atm -/- mouse thymic lymphoma cells were more radioresistant to radiation-induced apoptosis than wild-type mouse thymic lymphoma cells. Irradiated wild-type cells, but not Atm -/- cells, had decreased PKCδ levels, indicating that the Atm protein is involved in radiation-induced apoptosis through the induction of PKCδ degradation. The decreased Atm protein levels induced by treatment with Atm small interfering RNA had no effect on radiation-induced apoptosis in 3SBH5 cells. These results suggest that the regulation of radiation-induced PKCδ activation, which is distinct from the Atm-mediated cascade, determines radiation sensitivity in radiosensitive 3SBH5 cells
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Pump cavitation and inducer design
International Nuclear Information System (INIS)
Heslenfeld, M.W.; Hes, M. de
2002-01-01
Details of past work on sodium pump development and cavitation studies executed mainly for SNR 300 were reported earlier. Among the requirements for large sodium pumps are long life (200000 hours up to 300000 hours) and small size of impeller and pump, fully meeting the process and design criteria. These criteria are the required 'Q, H, r characteristics' in combination with a low NPSH value and the avoidance of cavitation damage to the pump. The pump designer has to develop a sound hydraulic combination consisting of suction arrangement, impeller design and diffuser. On the other hand the designer is free to choose an optimal pump speed. The pump speed in its turn influences the rotor dynamic pump design and the pump drive. The introduction of the inducer as an integral part of the pump design is based on following advantages: no tip cavitation; (possible) cavitation bubbles move to the open centre due to centrifugal forces on the fluid; the head of the inducer improves the inlet conditions of the impeller. The aim of an inducer is the increase in the suction specific speed (SA value) of a pump whereby the inducer functions as a pressure source improving the impeller inlet conditions. With inducer-impeller combinations values up to SA=15000 are realistic. With the use of an inducer the overall pump sizes can be reduced with Ca. 30%. Pumps commonly available have SA values up to a maximum of ca. 10000. A development programme was executed for SNR 300 in order to reach an increase of the suction specific speed of the impeller from SA 8200 to SA 11000. Further studies to optimize pumps design for the follow up line introduced the 'inducer acting as a pre-impeller' development. This programme was executed in the period 1979-1981. At the FDO premises a scale 1 2.8 inducer impeller combination with a suction specific speed SA=15000 was developed, constructed and tested at the water test rig. This water test rig is equipped with a perspex pipe allowing also visualisation
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International Nuclear Information System (INIS)
Mori, Jun; Takahashi-Yanaga, Fumi; Miwa, Yoshikazu; Watanabe, Yutaka; Hirata, Masato; Morimoto, Sachio; Shirasuna, Kanemitsu; Sasaguri, Toshiyuki
2005-01-01
Differentiation-inducing factors (DIFs) are morphogens which induce cell differentiation in Dictyostelium. We reported that DIF-1 and DIF-3 inhibit proliferation and induce differentiation in mammalian cells. In this study, we investigated the effect of DIF-1 on oral squamous cell carcinoma cell lines NA and SAS, well differentiated and poorly differentiated cell lines, respectively. Although DIF-1 did not induce the expression of cell differentiation makers in these cell lines, it inhibited the proliferation of NA and SAS in a dose-dependent manner by restricting the cell cycle in the G 0 /G 1 phase. DIF-1 induced cyclin D1 degradation, but this effect was prevented by treatment with lithium chloride and SB216763, the inhibitors of glycogen synthase kinase-3β (GSK-3β). Depletion of endogenous GSK-3β by RNA interference also attenuated the effect of DIF-1 on cyclin D1 degradation. Therefore, we investigated the effect of DIF-1 on GSK-3β and found that DIF-1 dephosphorylated GSK-3β on Ser 9 and induced the nuclear translocation of GSK-3β, suggesting that DIF-1 activated GSK-3β. Then, we examined the effect of DIF-1 on cyclin D1 mutants (Thr286Ala, Thr288Ala, and Thr286/288Ala). We revealed that Thr286Ala and Thr286/288Ala mutants were highly resistant to DIF-1-induced degradation compared with wild-type cyclin D1, indicating that the phosphorylation of Thr 286 was critical for cyclin D1 degradation induced by DIF-1. These results suggest that DIF-1 induces degradation of cyclin D1 through the GSK-3β-mediated phosphorylation of Thr 286
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Radiation-induced radical ions in calcium sulfite
Bogushevich, S. E.
2006-07-01
We have used EPR to study the effect of γ radiation on calcium sulfite. We have observed and identified the radiation-induced radical ions SO 2 - (iso) with g = 2.0055 and SO 2 - (orth-1) with g1 = 2.0093, g2 = 2.0051, g3 = 2.0020, identical to the initial and thermally induced SO 2 - respectively, SO 3 - (iso) with g = 2.0031 and SO 3 - (axial) with g⊥ = 2.0040, g∥ = 2.0023, identical to mechanically induced SO 3 - . We have established the participation of radiation-induced radical ions SO 3 - in formation of post-radiation SO 2 - .
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Evaluation of induced seismicity forecast models in the Induced Seismicity Test Bench
Király, Eszter; Gischig, Valentin; Zechar, Jeremy; Doetsch, Joseph; Karvounis, Dimitrios; Wiemer, Stefan
2016-04-01
Induced earthquakes often accompany fluid injection, and the seismic hazard they pose threatens various underground engineering projects. Models to monitor and control induced seismic hazard with traffic light systems should be probabilistic, forward-looking, and updated as new data arrive. Here, we propose an Induced Seismicity Test Bench to test and rank such models. We apply the test bench to data from the Basel 2006 and Soultz-sous-Forêts 2004 geothermal stimulation projects, and we assess forecasts from two models that incorporate a different mix of physical understanding and stochastic representation of the induced sequences: Shapiro in Space (SiS) and Hydraulics and Seismics (HySei). SiS is based on three pillars: the seismicity rate is computed with help of the seismogenic index and a simple exponential decay of the seismicity; the magnitude distribution follows the Gutenberg-Richter relation; and seismicity is distributed in space based on smoothing seismicity during the learning period with 3D Gaussian kernels. The HySei model describes seismicity triggered by pressure diffusion with irreversible permeability enhancement. Our results show that neither model is fully superior to the other. HySei forecasts the seismicity rate well, but is only mediocre at forecasting the spatial distribution. On the other hand, SiS forecasts the spatial distribution well but not the seismicity rate. The shut-in phase is a difficult moment for both models in both reservoirs: the models tend to underpredict the seismicity rate around, and shortly after, shut-in. Ensemble models that combine HySei's rate forecast with SiS's spatial forecast outperform each individual model.
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Energy Technology Data Exchange (ETDEWEB)
Zhang, Wei [Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096 (China); Department of Respiration, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Zhang, Mei, E-mail: meizhang1717@163.com [Department of Respiration, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Wang, Zhongjiang [Department of Radiology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Cheng, Yusi; Liu, Haijun [Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Zhou, Zewei [Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Han, Bing [Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Chen, Baoan [Department of Hematology and Oncology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Yao, Honghong, E-mail: yaohh@seu.edu.cn [Department of Pharmacology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096 (China); Chao, Jie, E-mail: chaojie@seu.edu.cn [Department of Physiology, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China); Key Laboratory of Developmental Genes and Human Disease, Southeast University, Nanjing 210096 (China); Department of Respiration, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, Jiangsu 210009 (China)
2016-10-15
Background: Silicosis is a systemic disease caused by inhaling silicon dioxide (SiO{sub 2}); early stages are characterized by alveolar inflammation, and later stages are characterized by progressive lung fibrosis. Mounting evidence indicates that high-mobility group box 1 (HMGB1) is involved in pulmonary fibrosis. Whether neogambogic acid (NGA) inhibits macrophage and fibroblast activation induced by SiO{sub 2} by targeting HMGB1 remains unclear. Methods and results: Experiments using cultured mouse macrophages (RAW264.7 cells) demonstrated that SiO{sub 2} treatment induces the expression of HMGB1 in a time- and dose-dependent manner via mitogen-activated protein kinases (MAPKs) and the phosphatidylinositol 3-kinase (PI3K)/Akt pathway; in turn, this expression causes macrophage apoptosis and fibroblast activation. Pretreating macrophages with NGA inhibited the HMGB1 expression induced by SiO{sub 2} and attenuated both macrophage apoptosis and fibroblast activation. Moreover, NGA directly inhibited MCP-1-induced protein 1 (MCPIP1) expression, as well as markers of fibroblast activation and migration induced by SiO{sub 2}. Furthermore, the effects of NGA on macrophages and fibroblasts were confirmed in vivo by exposing mice to SiO{sub 2}. Conclusion: NGA can prevent SiO{sub 2}-induced macrophage activation and apoptosis via HMGB1 inhibition and SiO{sub 2}-induced fibrosis via the MCPIP1 pathway. Targeting HMGB1 and MCPIP1 with NGA could provide insights into the potential development of a therapeutic approach for alleviating the inflammation and fibrosis induced by SiO{sub 2}. - Highlights: • The SiO{sub 2} induced HMGB1 in alveolar macrophage and MCPIP1 in fibroblast. • NGA rescued the SiO{sub 2}-induced apoptosis of alveolar macrophages via HMGB1 signaling. • NGA inhibited the fibroblast activation induced by SiO{sub 2} via MCPIP1 signaling. • NGA might represent a potential therapeutic approach for silicosis.
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International Nuclear Information System (INIS)
Chen, Rui; Wang, Bin; Chen, Ling; Cai, Dunpeng; Li, Bing; Chen, Chuanxiang; Huang, Enping; Liu, Chao; Lin, Zhoumeng; Xie, Wei-Bing; Wang, Huijun
2016-01-01
Methamphetamine (METH) is an amphetamine-like psychostimulant that is commonly abused. Previous studies have shown that METH can induce damages to the nervous system and recent studies suggest that METH can also cause adverse and potentially lethal effects on the cardiovascular system. Recently, we demonstrated that DNA damage-inducible transcript 4 (DDIT4) regulates METH-induced neurotoxicity. However, the role of DDIT4 in METH-induced cardiotoxicity remains unknown. We hypothesized that DDIT4 may mediate METH-induced autophagy and apoptosis in cardiomyocytes. To test the hypothesis, we examined DDIT4 protein expression in cardiomyocytes and in heart tissues of rats exposed to METH with Western blotting. We also determined the effects on METH-induced autophagy and apoptosis after silencing DDIT4 expression with synthetic siRNA with or without pretreatment of a mTOR inhibitor rapamycin in cardiomyocytes using Western blot analysis, fluorescence microscopy and TUNEL staining. Our results showed that METH exposure increased DDIT4 expression and decreased phosphorylation of mTOR that was accompanied with increased autophagy and apoptosis both in vitro and in vivo. These effects were normalized after silencing DDIT4. On the other hand, rapamycin promoted METH-induced autophagy and apoptosis in DDIT4 knockdown cardiomyocytes. These results suggest that DDIT4 mediates METH-induced autophagy and apoptosis through mTOR signaling pathway in cardiomyocytes. - Highlights: • METH exposure increases DDIT4 expression in cardiomyocytes. • DDIT4 mediates METH-induced autophagy and apoptosis in cardiomyocytes. • DDIT4 silencing protects cardiomyocytes against METH-caused autophagy and apoptosis.
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Energy Technology Data Exchange (ETDEWEB)
Chen, Rui [Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515 (China); Department of Forensic Medicine, Guangdong Medical University, Dongguan 523808 (China); Wang, Bin; Chen, Ling; Cai, Dunpeng; Li, Bing; Chen, Chuanxiang; Huang, Enping [Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515 (China); Liu, Chao [Guangzhou Forensic Science Institute, Guangzhou 510030 (China); Lin, Zhoumeng [Institute of Computational Comparative Medicine and Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506 (United States); Xie, Wei-Bing, E-mail: xieweib@126.com [Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515 (China); Wang, Huijun, E-mail: hjwang711@yahoo.cn [Department of Forensic Medicine, School of Basic Medical Science, Southern Medical University, Guangzhou 510515 (China)
2016-03-15
Methamphetamine (METH) is an amphetamine-like psychostimulant that is commonly abused. Previous studies have shown that METH can induce damages to the nervous system and recent studies suggest that METH can also cause adverse and potentially lethal effects on the cardiovascular system. Recently, we demonstrated that DNA damage-inducible transcript 4 (DDIT4) regulates METH-induced neurotoxicity. However, the role of DDIT4 in METH-induced cardiotoxicity remains unknown. We hypothesized that DDIT4 may mediate METH-induced autophagy and apoptosis in cardiomyocytes. To test the hypothesis, we examined DDIT4 protein expression in cardiomyocytes and in heart tissues of rats exposed to METH with Western blotting. We also determined the effects on METH-induced autophagy and apoptosis after silencing DDIT4 expression with synthetic siRNA with or without pretreatment of a mTOR inhibitor rapamycin in cardiomyocytes using Western blot analysis, fluorescence microscopy and TUNEL staining. Our results showed that METH exposure increased DDIT4 expression and decreased phosphorylation of mTOR that was accompanied with increased autophagy and apoptosis both in vitro and in vivo. These effects were normalized after silencing DDIT4. On the other hand, rapamycin promoted METH-induced autophagy and apoptosis in DDIT4 knockdown cardiomyocytes. These results suggest that DDIT4 mediates METH-induced autophagy and apoptosis through mTOR signaling pathway in cardiomyocytes. - Highlights: • METH exposure increases DDIT4 expression in cardiomyocytes. • DDIT4 mediates METH-induced autophagy and apoptosis in cardiomyocytes. • DDIT4 silencing protects cardiomyocytes against METH-caused autophagy and apoptosis.
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Thymus function in drug-induced lupus.
Rubin, R L; Salomon, D R; Guerrero, R S
2001-01-01
Autoimmunity develops when a lupus-inducing drug is introduced into the thymus of normal mice, but the relevance of this model to the human disorder is unclear in part because it is widely assumed that the thymus is non-functional in the adult. We compared thymus function in 10 patients with symptomatic procainamide-induced lupus to that in 13 asymptomatic patients who only developed drug-induced autoantibodies. T cell output from the thymus was quantified using a competitive polymerase chain reaction that detects T cell receptor DNA excision circles in peripheral blood lymphocytes. Despite the advanced age of the patient population under study, newly generated T cells were detected in all subjects. Although there was no overall quantitative difference between the symptomatic and asymptomatic patients, we found a positive correlation between the level of T cell receptor excision circles in peripheral lymphocytes and serum IgG anti-chromatin antibody activity in patients with drug-induced lupus. The association between autoantibodies and nascent peripheral T cells supports the requirement for T cells in autoantibody production. Our observations are consistent with findings in mice in which autoreactive T cells derived from drug-induced abnormalities in T cell development in the thymus.
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Genetic alterations during radiation-induced carcinogenesis
International Nuclear Information System (INIS)
Kodama, Seiji
1995-01-01
This paper reviews radiation-induced genetic alterations and its carcinogenesis, focusing on the previous in vitro assay outcome. A colony formation assay using Syrian hamster fetal cells and focus formation assay using mouse C3H10T1/2 cells are currently available to find malignant transformation of cells. Such in vitro assays has proposed the hypothesis that radiation-induced carcinogenesis arises from at least two-stage processes; i.e., that an early step induced by irradiation plays an important role in promoting the potential to cause the subsequent mutation. A type of genetic instability induced by radiation results in a persistently elevated frequency of spontaneous mutations, so-called the phenomenon of delayed reproductive death. One possible mechanism by which genetic instability arises has been shown to be due to the development of abnormality in the gene group involved in the maintenance mechanism of genome stability. Another possibility has also been shown to stem from the loss of telomere (the extremities of a chromosome). The importance of search for radiation-induced genetic instability is emphasized in view of the elucidation of carcinogenesis. (N.K.)
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Characterization of ion beam induced nanostructures
International Nuclear Information System (INIS)
Ghatak, J.; Satpati, B.; Umananda, M.; Kabiraj, D.; Som, T.; Dev, B.N.; Akimoto, K.; Ito, K.; Emoto, T.; Satyam, P.V.
2006-01-01
Tailoring of nanostructures with energetic ion beams has become an active area of research leading to the fundamental understanding of ion-solid interactions at nanoscale regime and with possible applications in the near future. Rutherford backscattering spectrometry (RBS), high resolution transmission electron microscopy (HRTEM) and asymmetric X-ray Bragg-rocking curve experimental methods have been used to characterize ion-induced effects in nanostructures. The possibility of surface and sub-surface/interface alloying at nano-scale regime, ion-beam induced embedding, crater formation, sputtering yield variations for systems with isolated nanoislands, semi-continuous and continuous films of noble metals (Au, Ag) deposited on single crystalline silicon will be reviewed. MeV-ion induced changes in specified Au-nanoislands on silicon substrate are tracked as a function of ion fluence using ex situ TEM. Strain induced in the bulk silicon substrate surface due to 1.5 MeV Au 2+ and C 2+ ion beam irradiation is determined by using HRTEM and asymmetric Bragg X-ray rocking curve methods. Preliminary results on 1.5 MeV Au 2+ ion-induced effects in nanoislands of Co deposited on silicon substrate will be discussed
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van't Hof, R J; Armour, K J; Smith, L M; Armour, K E; Wei, X Q; Liew, F Y; Ralston, S H
2000-07-05
Nitric oxide has been suggested to be involved in the regulation of bone turnover, especially in pathological conditions characterized by release of bone-resorbing cytokines. The cytokine IL-1 is thought to act as a mediator of periarticular bone loss and tissue damage in inflammatory diseases such as rheumatoid arthritis. IL-1 is a potent stimulator of both osteoclastic bone resorption and expression of inducible nitric oxide synthase (iNOS) in bone cells and other cell types. In this study, we investigated the role that the iNOS pathway plays in mediating the bone-resorbing effects of IL-1 by studying mice with targeted disruption of the iNOS gene. Studies in vitro and in vivo showed that iNOS-deficient mice exhibited profound defects of IL-1-induced osteoclastic bone resorption but responded normally to calciotropic hormones such as 1,25 dihydroxyvitamin D3 and parathyroid hormone. Immunohistochemical studies and electrophoretic mobility shift assays performed on bone marrow cocultures from iNOS-deficient mice showed abnormalities in IL-1-induced nuclear translocation of the p65 component of NFkappaB and in NFkappaB-DNA binding, which were reversed by treatment with the NO donor S-nitroso-acetyl penicillamine. These results show that the iNOS pathway is essential for IL-1-induced bone resorption and suggest that the effects of NO may be mediated by modulating IL-1-induced nuclear activation of NFkappaB in osteoclast precursors.
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van't Hof, R. J.; Armour, K. J.; Smith, L. M.; Armour, K. E.; Wei, X. Q.; Liew, F. Y.; Ralston, S. H.
2000-01-01
Nitric oxide has been suggested to be involved in the regulation of bone turnover, especially in pathological conditions characterized by release of bone-resorbing cytokines. The cytokine IL-1 is thought to act as a mediator of periarticular bone loss and tissue damage in inflammatory diseases such as rheumatoid arthritis. IL-1 is a potent stimulator of both osteoclastic bone resorption and expression of inducible nitric oxide synthase (iNOS) in bone cells and other cell types. In this study, we investigated the role that the iNOS pathway plays in mediating the bone-resorbing effects of IL-1 by studying mice with targeted disruption of the iNOS gene. Studies in vitro and in vivo showed that iNOS-deficient mice exhibited profound defects of IL-1-induced osteoclastic bone resorption but responded normally to calciotropic hormones such as 1,25 dihydroxyvitamin D3 and parathyroid hormone. Immunohistochemical studies and electrophoretic mobility shift assays performed on bone marrow cocultures from iNOS-deficient mice showed abnormalities in IL-1-induced nuclear translocation of the p65 component of NFκB and in NFκB-DNA binding, which were reversed by treatment with the NO donor S-nitroso-acetyl penicillamine. These results show that the iNOS pathway is essential for IL-1-induced bone resorption and suggest that the effects of NO may be mediated by modulating IL-1-induced nuclear activation of NFκB in osteoclast precursors. PMID:10869429
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Prevention and Treatment of Noise-Induced Tinnitus
2014-09-01
Tinnitus PRINCIPAL INVESTIGATOR: Dr. Richard A. Altschuler CONTRACTING ORGANIZATION: University of Michigan REPORT DATE: 2014...3 Ju 2014 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Prevention and Treatment of Noise-Induced Tinnitus 5b. GRANT NUMBER 5c. PROGRAM...prevent or treat noise induced tinnitus . Our studies showed a military relevant small arms fire-like noise will induce tinnitus in approximately 33
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Snake antivenom for snake venom induced consumption coagulopathy
Maduwage, Kalana; Buckley, Nick A.; Janaka de Silva, H.; Lalloo, David; Isbister, Geoffrey K.
2015-01-01
Background\\ud \\ud Snake venom induced consumption coagulopathy is a major systemic effect of envenoming. Observational studies suggest that antivenom improves outcomes for venom induced consumption coagulopathy in some snakebites and not others. However, the effectiveness of snake antivenom in all cases of venom induced consumption coagulopathy is controversial.\\ud \\ud Objectives\\ud \\ud To assess the effect of snake antivenom as a treatment for venom induced consumption coagulopathy in people...
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Directory of Open Access Journals (Sweden)
Yingmin Liang
2017-07-01
Full Text Available The strong relationship between cigarette smoking and cardiovascular disease (CVD has been well-documented, but the mechanisms by which smoking increases CVD risk appear to be multifactorial and incompletely understood. Mesenchymal stem cells (MSCs are regarded as an important candidate for cell-based therapy in CVD. We hypothesized that MSCs derived from induced pluripotent stem cell (iPSC-MSCs or bone marrow (BM-MSCs might alleviate cigarette smoke (CS-induced cardiac injury. This study aimed to investigate the effects of BM-MSCs or iPSC-MSCs on CS-induced changes in serum and cardiac lipid profiles, oxidative stress and inflammation as well as cardiac function in a rat model of passive smoking. Male Sprague-Dawley rats were randomly selected for exposure to either sham air (SA as control or 4% CS for 1 h per day for 56 days. On day 29 and 43, human adult BM-MSCs, iPSC-MSCs or PBS were administered intravenously to CS-exposed rats. Results from echocardiography, serum and cardiac lipid profiles, cardiac antioxidant capacity, cardiac pro- and anti-inflammatory cytokines and cardiac morphological changes were evaluated at the end of treatment. iPSC-MSC-treated group showed a greater effect in the improvement of CS-induced cardiac dysfunction over BM-MSCs-treated group as shown by increased percentage left ventricular ejection fraction and percentage fractional shortening, in line with the greater reversal of cardiac lipid abnormality. In addition, iPSC-MSCs administration attenuated CS-induced elevation of cardiac pro-inflammatory cytokines as well as restoration of anti-inflammatory cytokines and anti-oxidative markers, leading to ameliorate cardiac morphological abnormalities. These data suggest that iPSC-MSCs on one hand may restore CS-induced cardiac lipid abnormality and on the other hand may attenuate cardiac oxidative stress and inflammation via inhibition of CS-induced NF-κB activation, leading to improvement of cardiac remodeling and
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Induced disease resistance signaling in plants
Verhagen, B.W.M.; Loon, L.C. van; Pieterse, C.M.J.
2006-01-01
To protect themselves from disease, plants have evolved sophisticated inducible defense mechanisms in which the signal molecules salicylic acid, jasmonic acid and ethylene often play crucial roles. Elucidation of signaling pathways controlling induced disease resistance is a major objective in
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DEFF Research Database (Denmark)
Rødningen, Olaug Kristin; Børresen-Dale, Anne-Lise; Alsner, Jan
2008-01-01
BACKGROUND AND PURPOSE: Breast cancer patients show a large variation in normal tissue reactions after ionizing radiation (IR) therapy. One of the most common long-term adverse effects of ionizing radiotherapy is radiation-induced fibrosis (RIF), and several attempts have been made over the last...... years to develop predictive assays for RIF. Our aim was to identify basal and radiation-induced transcriptional profiles in fibroblasts from breast cancer patients that might be related to the individual risk of RIF in these patients. MATERIALS AND METHODS: Fibroblast cell lines from 31 individuals......-treated fibroblasts. Transcriptional differences in basal and radiation-induced gene expression profiles were investigated using 15K cDNA microarrays, and results analyzed by both SAM and PAM. RESULTS: Sixty differentially expressed genes were identified by applying SAM on 10 patients with the highest risk of RIF...
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2016-05-01
Hair loss can have major psychological consequences. It can be due to a wide variety of causes, including hormonal disorders, dietary factors, infections, inflammation, trauma, emotional factors, and cancer. Drugs can also induce hair loss, by interacting with the hair growth cycle. Drug-induced hair loss may be immediate or delayed, sudden or gradual, and diffuse or localised. It is usually reversible after drug discontinuation. The drugs most often implicated in hair loss are anticancer agents, interferon, azole antifungals, lithium, immunosuppressants, and many other drugs belonging to a variety of pharmacological classes.
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Cyclophosphamide-induced pulmonary toxicity
International Nuclear Information System (INIS)
Siemann, D.W.; Macler, L.; Penney, D.P.
1986-01-01
Unlike radiation effects, pulmonary toxicity following drug treatments may develop soon after exposure. The dose-response relationship between Cyclophosphamide and lung toxicity was investigated using increased breathing frequency assays used successfully for radiation induced injury. The data indicate that release of protein into the alveolus may play a significant role in Cy induced pulmonary toxicity. Although the mechanism responsible for the increased alveolar protein is as yet not identified, the present findings suggest that therapeutic intervention to inhibit protein release may be an approach to protect the lungs from toxic effects. (UK)
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Role of neurotensin in radiation-induced hypothermia in rats
International Nuclear Information System (INIS)
Kandasamy, S.B.; Hunt, W.A.; Harris, A.H.
1991-01-01
The role of neurotensin in radiation-induced hypothermia was examined. Intracerebroventricular (ICV) administration of neurotensin produced dose-dependent hypothermia. Histamine appears to mediate neurotensin-induced hypothermia because the mast cell stabilizer disodium cromoglycate and antihistamines blocked the hypothermic effects of neurotensin. An ICV pretreatment with neurotensin antibody attenuated neurotensin-induced hypothermia, but did not attenuate radiation-induced hypothermia, suggesting that radiation-induced hypothermia was not mediated by neurotensin
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Flow-induced vibration -- 1994. PVP-Volume 273
International Nuclear Information System (INIS)
Au-Yang, M.K.; Fujita, K.
1994-01-01
Flow-induced vibration is a subject of practical interest to many engineering disciplines, including the power generation, process, and petrochemical industries. In the nuclear industry, flow-induced vibration reaches a higher level of concern because of safety issues and the huge cost associated with down time and site repair. Not surprisingly, during the last 25 years a tremendous amount of effort has been spent in the study of flow-induced vibration phenomena related to nuclear plant components, notably nuclear steam generator tube banks and nuclear fuel bundles. Yet, in spite of this concentrated effort, the industry is still not free from flow-induced vibration-related problems. This explains why in this volume almost half of the papers address the issue of cross-flow induced vibration in tube bundles, with applications to the nuclear steam generator and nuclear fuel bundles in mind. Unlike 10 or 15 years ago, when flow-induced vibration studies almost always involved experimentation and empirical studies, the advent of high-speed computers has enabled numerical calculation and simulation of this complex phenomenon to take place. Separate abstracts were prepared for 27 papers in this volume
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Curvature-Induced Instabilities of Shells
Pezzulla, Matteo; Stoop, Norbert; Steranka, Mark P.; Bade, Abdikhalaq J.; Holmes, Douglas P.
2018-01-01
Induced by proteins within the cell membrane or by differential growth, heating, or swelling, spontaneous curvatures can drastically affect the morphology of thin bodies and induce mechanical instabilities. Yet, the interaction of spontaneous curvature and geometric frustration in curved shells remains poorly understood. Via a combination of precision experiments on elastomeric spherical shells, simulations, and theory, we show how a spontaneous curvature induces a rotational symmetry-breaking buckling as well as a snapping instability reminiscent of the Venus fly trap closure mechanism. The instabilities, and their dependence on geometry, are rationalized by reducing the spontaneous curvature to an effective mechanical load. This formulation reveals a combined pressurelike term in the bulk and a torquelike term in the boundary, allowing scaling predictions for the instabilities that are in excellent agreement with experiments and simulations. Moreover, the effective pressure analogy suggests a curvature-induced subcritical buckling in closed shells. We determine the critical buckling curvature via a linear stability analysis that accounts for the combination of residual membrane and bending stresses. The prominent role of geometry in our findings suggests the applicability of the results over a wide range of scales.
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Cellular Responses to Cisplatin-Induced DNA Damage
Directory of Open Access Journals (Sweden)
Alakananda Basu
2010-01-01
Full Text Available Cisplatin is one of the most effective anticancer agents widely used in the treatment of solid tumors. It is generally considered as a cytotoxic drug which kills cancer cells by damaging DNA and inhibiting DNA synthesis. How cells respond to cisplatin-induced DNA damage plays a critical role in deciding cisplatin sensitivity. Cisplatin-induced DNA damage activates various signaling pathways to prevent or promote cell death. This paper summarizes our current understandings regarding the mechanisms by which cisplatin induces cell death and the bases of cisplatin resistance. We have discussed various steps, including the entry of cisplatin inside cells, DNA repair, drug detoxification, DNA damage response, and regulation of cisplatin-induced apoptosis by protein kinases. An understanding of how various signaling pathways regulate cisplatin-induced cell death should aid in the development of more effective therapeutic strategies for the treatment of cancer.
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Hierarchical Bayesian Modeling of Fluid-Induced Seismicity
Broccardo, M.; Mignan, A.; Wiemer, S.; Stojadinovic, B.; Giardini, D.
2017-11-01
In this study, we present a Bayesian hierarchical framework to model fluid-induced seismicity. The framework is based on a nonhomogeneous Poisson process with a fluid-induced seismicity rate proportional to the rate of injected fluid. The fluid-induced seismicity rate model depends upon a set of physically meaningful parameters and has been validated for six fluid-induced case studies. In line with the vision of hierarchical Bayesian modeling, the rate parameters are considered as random variables. We develop both the Bayesian inference and updating rules, which are used to develop a probabilistic forecasting model. We tested the Basel 2006 fluid-induced seismic case study to prove that the hierarchical Bayesian model offers a suitable framework to coherently encode both epistemic uncertainty and aleatory variability. Moreover, it provides a robust and consistent short-term seismic forecasting model suitable for online risk quantification and mitigation.
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Ubiquitin-dependent system controls radiation induced apoptosis
International Nuclear Information System (INIS)
Delic, J.; Magdelenat, H.; Glaisner, S.; Magdelenat, H.; Maciorowski, Z.
1997-01-01
The selective proteolytic pathway, dependent upon 'N-end rule' protein recognition/ubiquitination and on the subsequent proteasome dependent processing of ubiquitin conjugates, operates in apoptosis induced by γ-irradiation. The proteasome inhibitor peptide aldehyde, MG132, efficiently induced apoptosis and was also able (at doses lower than those required for apoptosis induction) to potentiate apoptosis induced by DNA damage. Its specificity is suggested by the induction of the ubiquitin (UbB and UbC) and E1 (ubiquitin activating enzyme) genes and by an altered ubiquitination pattern. More selectively, a di-peptide competitor of the 'N-end rule' of ubiquitin dependent protein processing inhibited radiation induced apoptosis. This inhibition is also followed by an altered ubiquitination pattern and by activation of Poly (ADP-ribose) polymerase (PARP). These data strongly suggest that early apoptosis radiation induced events are controlled by ubiquitin-dependent proteolytic processing. (author)
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DEFF Research Database (Denmark)
Johansen, Maria E; Jensen, Jens-Ulrik; Bestle, Morten H
2014-01-01
INTRODUCTION: Coagulopathy associates with poor outcome in sepsis. Mild induced hypothermia has been proposed as treatment in sepsis but it is not known whether this intervention worsens functional coagulopathy. MATERIALS AND METHODS: Interim analysis data from an ongoing randomized controlled...... trial; The Cooling And Surviving Septic shock (CASS) study. Patients suffering severe sepsis/septic shock are allocated to either mild induced hypothermia (cooling to 32-34°C for 24hours) or control (uncontrolled temperature). TRIAL REGISTRATION: NCT01455116. Thrombelastography (TEG) is performed three....... At enrollment, 3%, 38%, and 59% had a hypocoagulable, normocoagulable, and hypercoagulable TEG clot strength (MA), respectively. In the hypothermia group, functional coagulopathy improved during the hypothermia phase, measured by R and MA, in patients with hypercoagulation as well as in patients...
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Inducible limb-shaking transitory ischemic attacks
DEFF Research Database (Denmark)
Rosenbaum, Sverre; Ovesen, Christian; Futrell, Nancy
2016-01-01
with exercise-induced weakness associated with tremor in his right arm. His left internal carotid artery was occluded at the bifurcation. Administration of statin and antiplatelet did not relieve his symptoms, and his stereotypic, exercise-induced "limb-shaking" episodes persisted. He underwent successful...
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He, Ping; Zhou, Renmin; Hu, Guorui; Liu, Zhifeng; Jin, Yu; Yang, Guang; Li, Mei; Lin, Qian
2015-03-01
Curcumin is known to possess anti‑inflammatory properties. Despite the fact that curcumin is known to be a strong inhibitor of H+, K+‑ATPase activity, the mechanism underlying the curcumin‑induced inhibition of the transcription of the H+, K+‑ATPase α subunit in gastric mucosal parietal cells remains unclear. The present study investigated the possible mechanism by which curcumin inhibits stomach H+, K+‑ATPase activity during the acute phase of gastric ulcer disease. A rat model of stress‑induced gastric ulcers was produced, in which the anti‑ulcer effects of curcumin were examined. Curcumin‑induced inhibition of the H+, K+‑ATPase promoter via histone acetylation, was verified using a chromatin immunoprecipitation assay. The results showed that curcumin improved stress‑induced gastric ulcer disease in rats, as demonstrated by increased pH values and reduced gastric mucosal hemorrhage and ulcer index. These effects were accompanied by a significant reduction in the level of histone H3 acetylation at the site of the H+, K+‑ATPase promoter and in the expression of the gastric H+,K+‑ATPase α subunit gene and protein. In conclusion, curcumin downregulated the acetylation of histone H3 at the site of the H+, K+‑ATPase promoter gene, thereby inhibiting the transcription and expression of the H+, K+‑ATPase gene. Curcumin was shown to have a preventive and therapeutic effect in gastric ulcer disease.
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Electromagnetically induced absorption via incoherent collisions
International Nuclear Information System (INIS)
Yang Xihua; Sheng Jiteng; Xiao Min
2011-01-01
We conduct theoretical studies on electromagnetically induced absorption via incoherent collisions in an inhomogeneously broadened ladder-type three-level system with the density-matrix approach. The effects of the collision-induced coherence decay rates as well as the probe laser field intensity on the probe field absorption are examined. It is shown that with the increase of the collisional decay rates in a moderate range, a narrow dip due to electromagnetically induced transparency superimposed on the Doppler-broadened absorption background can be turned into a narrow peak under the conditions that the probe field intensity is not very weak as compared to the pump field, which results from the enhancement of constructive interference and suppression of destructive interference between one-photon and multiphoton transition pathways. The physical origin of the collision-assisted electromagnetically induced absorption is analyzed with a power-series solution of the density-matrix equations.
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Mechanisms of chemotherapy-induced behavioral toxicities
Directory of Open Access Journals (Sweden)
Elisabeth G Vichaya
2015-04-01
Full Text Available While chemotherapeutic agents have yielded relative success in the treatment of cancer, patients are often plagued with unwanted and even debilitating side-effects from the treatment which can lead to dose reduction or even cessation of treatment. Common side effects (symptoms of chemotherapy include (i cognitive deficiencies such as problems with attention, memory and executive functioning; (ii fatigue and motivational deficit; and (iii neuropathy. These symptoms often develop during treatment but can remain even after cessation of chemotherapy, severely impacting long-term quality of life. Little is known about the underlying mechanisms responsible for the development of these behavioral toxicities, however, neuroinflammation is widely considered to be one of the major mechanisms responsible for chemotherapy-induced symptoms. Here, we critically assess what is known in regards to the role of neuroinflammation in chemotherapy-induced symptoms. We also argue that, based on the available evidence neuroinflammation is unlikely the only mechanism involved in the pathogenesis of chemotherapy-induced behavioral toxicities. We evaluate two other putative candidate mechanisms. To this end we discuss the mediating role of damage-associated molecular patterns (DAMPs activated in response to chemotherapy-induced cellular damage. We also review the literature with respect to possible alternative mechanisms such as a chemotherapy-induced change in the bioenergetic status of the tissue involving changes in mitochondrial function in relation to chemotherapy-induced behavioral toxicities. Understanding the mechanisms that underlie the emergence of fatigue, neuropathy, and cognitive difficulties is vital to better treatment and long-term survival of cancer patients.
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Overexpression of BAG3 Attenuates Hypoxia-Induced Cardiomyocyte Apoptosis by Inducing Autophagy
Directory of Open Access Journals (Sweden)
Jiankai Zhang
2016-07-01
Full Text Available Background: Hypoxia is a well-known factor in the promotion of apoptosis, which contributes to the development of numerous cardiac diseases, such as heart failure and myocardial infarction. Inhibiting apoptosis is an important therapeutic strategy for the treatment of related heart diseases caused by ischemia/hypoxic injury. Previous studies have demonstrated that BAG3 plays an important role in cardiomyocyte apoptosis and survival. However, the role of BAG3 in hypoxia-induced cardiomyocyte apoptosis remains to be clarified. Here, we demonstrate that BAG3 is induced by hypoxia stimuli in cultured cardiomyocytes. Methods: BAG3 expression level was measured in H9c2 cells treated with hypoxia for 48 h. Cell proliferation and apoptosis were tested using MTT assay and Annexin V FITC-PI staining assay, respectively. The mRNA or protein expression level of BAG3, LC3-I, LC3-II, Atg5, NF-κB p65 and phosphorylated NF-κB p65 were assessed by qRT-PCR and western blot assay, respectively. Resluts: Overexpression of BAG3 inhibited cell apoptosis and promoted proliferation in hypoxia-injured H9c2 cells. Furthermore, autophagy and NF-κB were activated by BAG3 overexpression, and the NF-κB inhibitor PDTC could inhibit the activation of autophagy induced by BAG3 overexpression. In addition, the autophagy inhibitor 3-MA partly impeded the inhibitory effect of BAG3 on hypoxia-induced cardiomyocyte apoptosis. Conclusion: these results suggested that overexpression of BAG3 promoted cell proliferation and inhibited apoptosis by activating autophagy though the NF-κB signaling pathway in hypoxia-injured cardiomyocytes.
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Vlietman, Marianne; Sarfraz, Aashi Ambareen; Eskild, Anne
2010-12-01
the maternal age at child birth is increasing. If induced abortion is an important means of postponing childbirth in a population, it is to be expected that in young women the rate of conceived pregnancies is stable over time, but the induced abortion rate is increasing. We studied birth rates, induced abortion rates and the sum of these rates by maternal age during four decades. register-based study. all women 15-49 years living in Norway. we present temporal changes in birth rates and induced abortion rates within age groups during the period 1979-2007. We also estimated the sum rate of births and induced abortions. Data were obtained from national statistics. live births and induced abortions per 1000 women per year. the induced abortion rates have been relatively stable within age groups, except for a decrease in women 15-19 years (from 24.2 in 1979 to 17.0 in 2007) and an increase in women 20-24 years (from 23.2 to 29.5). The birth rates however, have decreased dramatically in women 20-24 years old (from 113.6 to 60.5). Hence, the sum rate of births and induced abortions in women 20-24 years old has decreased from 136.8 to 90.0. In women 30 years old or older, the birth rates have increased. the induced abortion rate has been relatively stable in all age groups over time, suggesting a limited influence of induced abortions on the postponement of childbearing.
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International Nuclear Information System (INIS)
Liu Hui; Jin Chufeng; Wu Yican; Ge Shenfang; Wu Lijun; FDS Team
2012-01-01
In this work, we investigated the bystander effect of the tumor and normal cells surrounding the target region caused by radiation-inducible target gene therapy combined with α-particle irradiation. The receptor tumor cell A549 and normal cell MRC-5 were co-cultured with the donor cells irradiated to 0.5 Gy or the non-irradiated donor cells, and their survival and apoptosis fractions were evaluated. The results showed that the combined treatment of Ad-ET and particle irradiation could induce synergistic antitumor effect on A549 tumor cell, and the survival fraction of receptor cells co-cultured with the irradiated cells decreased by 6%, compared with receptor cells co-cultured with non-irradiated cells, and the apoptosis fraction increased in the same circumstance, but no difference was observed with the normal cells. This study demonstrates that Ad-ET combined with α-particle irradiation can significantly cause the bystander effect on neighboring tumor cells by inhibiting cell growth and inducing apoptosis, without obvious toxicity to normal cells. This suggests that combining radiation-inducible TRAIL gene therapy and irradiation may improve tumor treatment efficacy by specifically targeting tumor cells and even involving the neighboring tumor cells. (authors)
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Induced Abortion: a Systematic Review and Meta-analysis.
Dastgiri, Saeed; Yoosefian, Maryam; Garjani, Mehraveh; Kalankesh, Leila R
2017-03-01
Induced abortion accounts for 1 in 8 of approximately 600000 maternal deaths that occur annually worldwide. Induced abortion rate can be considered as one of the indicators for assessing availability of the appropriate reproductive health plans for women and identifying needs for appropriate related health policies and programs. Researchers searched Pubmed, Google Scholar, CINAHL, Embase, PsycINFO, Cochrane, Iranian Scientific Information Database (SID), Iranian biomedical journals (Iranmedex), and Iranian Research Institute of Information and Documentation (Irandoc) between January 2000 and June 2013, which reported induced abortion. Search terms from two categories including abortion and termination of pregnancy were compiled. The search terms were "induced abortion", "illegal abortion", "illegal abortion", "unsafe abortion", and "criminal abortion". The search was also conducted with "induced termination of pregnancy", "illegal termination of pregnancy", "illegal termination of pregnancy", "unsafe termination of pregnancy" and "criminal termination of pregnancy". Meta-analysis was carried out by using OpenMeta software. Induced abortion rates were calculated based on the random effect model. Overall induced abortion rate was obtained 58.1 per 1000 women (95%CI: 55.16-61.04). In continental level, rate of induced abortion was 14 per 1000 women (95%CI: 11-16). Nation-wide and local rates were obtained 67.27 per 1000 women (95% CI: 60.02-74.23) and 148.92 (95% CI: 140.06-157.79) respectively. Induced abortion is a major public health problem that occurs worldwide whether under the legal restriction or freedom, and it remains as reproductive health concern globally. To eliminate the need for induced abortion is at the core of any effort for preventing this issue. Option with the highest priority is to prevent unwanted pregnancies through promoting reproductive health plans for women of reproductive age. In case the prevention strategies fail, universal provision of
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Laser-induced damage in optical materials
Ristau, Detlev
2014-01-01
Dedicated to users and developers of high-powered systems, Laser-Induced Damage in Optical Materials focuses on the research field of laser-induced damage and explores the significant and steady growth of applications for high-power lasers in the academic, industrial, and military arenas. Written by renowned experts in the field, this book concentrates on the major topics of laser-induced damage in optical materials and most specifically addresses research in laser damage that occurs in the bulk and on the surface or the coating of optical components. It considers key issues in the field of hi
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Molecular analysis of radiation-induced experimental tumors in mice
International Nuclear Information System (INIS)
Niwa, O.; Muto, M.; Suzuki, F.
1992-01-01
Molecular analysis was made on mouse tumors induced by radiation and chemicals. Expression of oncogenes was studied in 12 types of 178 mouse tumors. Southern blotting was done on tumors in which overexpression of oncogenes was noted. Amplification of the myc oncogene was found in chemically induced sarcomas, but not those induced by radiations. Radiogenic thymomas were studied in detail. These thymomas were induced in two different ways. The first was thymomas induced by direct irradiation of F1 mice between C57BL/6NxC3H/He. Southern analysis of DNA revealed deletion of specific minisatellite bands in these tumors. DNA from directly induced thymomas induced focus formation when transfected into normal Golden hamster cells. The mouse K-ras oncogene was detected in these transformants. The second type of thymomas was induced by X-irradiation of thymectomized B10.thy1.2 mice in which normal thymus from congenic B10,thy1.1. mice was grafted. Thymomas of the donor origin was analysed by transfection and the transformants by DNA from those indirectly induced thymomas did not contain activated ras oncogenes. (author)
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Beam induced rf cavity transient voltage
International Nuclear Information System (INIS)
Kramer, S.L.; Wang, J.M.
1998-10-01
The authors calculate the transient voltage induced in a radio frequency cavity by the injection of a relativistic bunched beam into a circular accelerator. A simplified model of the beam induced voltage, using a single tone current signal, is generated and compared with the voltage induced by a more realistic model of a point-like bunched beam. The high Q limit of the bunched beam model is shown to be related simply to the simplified model. Both models are shown to induce voltages at the resonant frequency ω r of the cavity and at an integer multiple of the bunch revolution frequency (i.e. the accelerating frequency for powered cavity operation) hω ο . The presence of two nearby frequencies in the cavity leads to a modulation of the carrier wave exp(hω ο t). A special emphasis is placed in this paper on studying the modulation function. These models prove useful for computing the transient voltage induced in superconducting rf cavities, which was the motivation behind this research. The modulation of the transient cavity voltage discussed in this paper is the physical basis of the recently observed and explained new kinds of longitudinal rigid dipole mode which differs from the conventional Robinson mode
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Hydrogen-Induced Cracking of the Drip Shield
International Nuclear Information System (INIS)
F. Hua
2004-01-01
Hydrogen-induced cracking is characterized by the decreased ductility and fracture toughness of a material due to the absorption of atomic hydrogen in the metal crystal lattice. Corrosion is the source of hydrogen generation. For the current design of the engineered barrier without backfill, hydrogen-induced cracking may be a concern because the titanium drip shield can be galvanically coupled to rock bolts (or wire mesh), which may fall onto the drip shield, thereby creating conditions for hydrogen production by electrochemical reaction. The purpose of this report is to analyze whether the drip shield will fail by hydrogen-induced cracking under repository conditions within 10,000 years after emplacement. Hydrogen-induced cracking is a scenario of premature failure of the drip shield. This report develops a realistic model to assess the form of hydrogen-induced cracking degradation of the drip shield under the hydrogen-induced cracking. The scope of this work covers the evaluation of hydrogen absorbed due to general corrosion and galvanic coupling to less noble metals (e.g., Stainless Steel Type 316 and carbon steels) under the repository conditions during the 10,000-year regulatory period after emplacement and whether the absorbed hydrogen content will exceed the critical hydrogen concentration value, above which the hydrogen-induced cracking is assumed to occur. This report also provides the basis for excluding the features, events, and processes (FEPs) related to hydrogen-induced cracking of the drip shield with particular emphasis on FEP 2.1.03.04.OB, hydride cracking of drip shields (DTN: M00407SEPFEPLA.000 [DIRS 170760]). This report is prepared according to ''Technical Work Plan (TWP) for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 169944])
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Interaction of alpha radiation with thermally-induced defects in silicon
International Nuclear Information System (INIS)
Ali, Akbar; Majid, Abdul
2008-01-01
The interaction of radiation-induced defects created by energetic alpha particles and thermally-induced defects in silicon has been studied using a Deep Level Transient Spectroscopy (DLTS) technique. Two thermally-induced defects at energy positions E c -0.48 eV and E c -0.25 eV and three radiation-induced defects E2, E3 and E5 have been observed. The concentration of both of the thermally-induced defects has been observed to increase on irradiation. It has been noted that production rates of the radiation-induced defects are suppressed in the presence of thermally-induced defects. A significant difference in annealing characteristics of thermally-induced defects in the presence of radiation-induced defects has been observed compared to the characteristics measured in pre-irradiated samples
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Smoke-induced seed germination in California chaparral
Keeley, J.E.; Fotheringham, C.J.
1998-01-01
The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that smoke also induces germination in these same species. Smoke is highly effective, often inducing 100% germination in deeply dormant seed populations with 0% control germination. Smoke induces germination both directly and indirectly by aqueous or gaseous transfer from soil to seeds. Neither nitrate nor ammonium ions were effective in stimulating germination of smoke-stimulated species, nor were most of the quantitatively important gases generated by biomass smoke. Nitrogen dioxide, however, was very effective at inducing germination in Caulanthus heterophyllus (Brassicaceae), Emmenanthe penduliflora (Hydrophyllaceae), Phacelia grandiflora (Hydrophyllaceae), and Silene multinervia (Caryophyllaceae). Three species, Dendromecon rigida (Papaveraceae), Dicentra chrysantha, and Trichostema lanatum (Lamiaceae), failed to germinate unless smoke treatment was coupled with prior treatment of 1 yr soil storage. Smoke-stimulated germination was found in 25 chaparral species, representing 11 families, none of which were families known for heat-shock-stimulated germination. Seeds of smoke-stimulated species have many analogous characteristics that separate them from most heat-shock-stimulated seeds, including: (1) outer seed coats that are highly textured, (2) a poorly developed outer cuticle, (3) absence of a dense palisade tissue in the seed coat, and (4) a subdermal membrane that is semipermeable, allowing water passage but blocking entry of large (molecular mass > 500) solutes. Tentative evidence suggests that permeability characteristics of this subdermal layer are altered by
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Energy Technology Data Exchange (ETDEWEB)
Abel, E.L. [Department of Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Science Park, Smithville, TX 78957 (United States); Boulware, S. [Division of Pharmacy and Toxicology, College of Pharmacy, The University of Texas at Austin, Dell Pediatric Research Institute, 1400 Barbara Jordan Blvd., Austin, TX 78723 (United States); Fields, T.; McIvor, E.; Powell, K.L. [Department of Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Science Park, Smithville, TX 78957 (United States); DiGiovanni, J.; Vasquez, K.M. [Division of Pharmacy and Toxicology, College of Pharmacy, The University of Texas at Austin, Dell Pediatric Research Institute, 1400 Barbara Jordan Blvd., Austin, TX 78723 (United States); MacLeod, M.C., E-mail: mcmacleod@mdanderson.org [Department of Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Science Park, Smithville, TX 78957 (United States)
2013-02-01
Mustard gas, used in chemical warfare since 1917, is a mutagenic and carcinogenic agent that produces severe dermal lesions for which there are no effective therapeutics; it is currently seen as a potential terrorist threat to civilian populations. Sulforaphane, found in cruciferous vegetables, is known to induce enzymes that detoxify compounds such as the sulfur mustards that react through electrophilic intermediates. Here, we observe that a single topical treatment with sulforaphane induces mouse epidermal levels of the regulatory subunit of glutamate-cysteine ligase, the rate-limiting enzyme in glutathione biosynthesis, and also increases epidermal levels of reduced glutathione. Furthermore, a glutathione S-transferase, GSTA4, is also induced in mouse skin by sulforaphane. In an in vivo model in which mice are given a single mutagenic application of the sulfur mustard analog 2-(chloroethyl) ethyl sulfide (CEES), we now show that therapeutic treatment with sulforaphane abolishes the CEES-induced increase in mutation frequency in the skin, measured four days after exposure. Sulforaphane, a natural product currently in clinical trials, shows promise as an effective therapeutic against mustard gas. -- Highlights: ► Sulforaphane induces increased levels of glutathione in mouse skin. ► Sulforaphane induces increased levels of GSTA4 in mouse skin. ► Sulforaphane, applied after CEES-treatment, completely abolishes CEES-mutagenesis. ► The therapeutic effect may suggest a long biological half-life for CEES in vivo.
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International Nuclear Information System (INIS)
Mecking, B.A.
1982-04-01
Various aspects of medium energy nuclear reactions induced by real photons are reviewed. Special emphasis is put on high accuracy experiments that will become possible with the next generation of electron accelerators. (orig.)
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Guanidinium-induced denaturation by breaking of salt bridges
Meuzelaar, H.; Panman, M.R.; Woutersen, S.
2015-01-01
Despite its wide use as a denaturant, the mechanism by which guanidinium (Gdm+) induces protein unfolding remains largely unclear. Herein, we show evidence that Gdm+ can induce denaturation by disrupting salt bridges that stabilize the folded conformation. We study the Gdm+-induced denaturation of
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Xylitol prevents NEFA-induced insulin resistance in rats
Kishore, P.; Kehlenbrink, S.; Hu, M.; Zhang, K.; Gutierrez-Juarez, R.; Koppaka, S.; El-Maghrabi, M. R.
2013-01-01
Aims/hypothesis Increased NEFA levels, characteristic of type 2 diabetes mellitus, contribute to skeletal muscle insulin resistance. While NEFA-induced insulin resistance was formerly attributed to decreased glycolysis, it is likely that glucose transport is the rate-limiting defect. Recently, the plant-derived sugar alcohol xylitol has been shown to have favourable metabolic effects in various animal models. Furthermore, its derivative xylulose 5-phosphate may prevent NEFA-induced suppression of glycolysis. We therefore examined whether and how xylitol might prevent NEFA-induced insulin resistance. Methods We examined the ability of xylitol to prevent NEFA-induced insulin resistance. Sustained ~1.5-fold elevations in NEFA levels were induced with Intralipid/heparin infusions during 5 h euglycaemic–hyperinsulinaemic clamp studies in 24 conscious non-diabetic Sprague-Dawley rats, with or without infusion of xylitol. Results Intralipid infusion reduced peripheral glucose uptake by ~25%, predominantly through suppression of glycogen synthesis. Co-infusion of xylitol prevented the NEFA-induced decreases in both glucose uptake and glycogen synthesis. Although glycolysis was increased by xylitol infusion alone, there was minimal NEFA-induced suppression of glycolysis, which was not affected by co-infusion of xylitol. Conclusions/interpretation We conclude that xylitol prevented NEFA-induced insulin resistance, with favourable effects on glycogen synthesis accompanying the improved insulin-mediated glucose uptake. This suggests that this pentose sweetener has beneficial insulin-sensitising effects. PMID:22460760
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Spatial and temporal ecology of oak toads (Bufo quercicus) on a Florida landscape.
Energy Technology Data Exchange (ETDEWEB)
Greenberg, Cathryn, H.; Tanner, George, W.
2005-12-01
ABSTRACT: We used data from 10 years of continuous, concurrent monitoring of oak toads at eight isolated, ephemeral ponds in Florida longleaf pine-wiregrass uplands to address: (1) did weather variables affect movement patterns of oak toads?; (2) did pond hydrology and the condition of surrounding uplands affect pond selection by adults or juvenile recruitment?; (3) were population trends evident?; and (4) did a classical metapopulation model best represent their population ecology? Of 4076 oak toads captured, 92.2% were adults. Substantial (n _ 30 exiting juveniles) recruitment occurred only three times (once each at three ponds during two years). Males outnumbered females (average for all years 2.3:1). Most captures occurred during May–September. Adult captures during June–August increased with heavier rainfall but were not influenced by the durations of preceding dry periods. Movement patterns of metamorphs suggested that oak toads emigrated when moisture conditions become favorable. Pond use by adults was correlated with maximum change in pond depth (May–September). Juvenile recruitment was negatively correlated with minimum pond depth and the number of weeks since a pond was last dry, and positively correlated with the maximum number of weeks a pond held water continuously. The number of breeding adults and juvenile recruitment were highest at ponds within the hardwood-invaded upland matrix. The direction of most immigrations and emigrations was nonrandom, but movement occurred from all directions, and the mean direction of pond entry and exit did not always correspond. A total of 21.1% of individuals was recaptured; 13.3% of first captures were recaptured during the same year, and 7.7% during a subsequent year. Only 1.9% of captured oak toads moved among ponds, mostly within a distance of 132 m. We did not detect adult population trends over the 10- yr studied. Presence or absence at ponds in any given year was a poor indicator of overall use. We saw little evidence of local extinction or ‘‘rescue,’’ but were unable to determine whether juveniles returned to natal ponds or colonized new ponds for breeding as adults. Oak toad conservation can best be ensured by maintaining multiple ponds within a landscape to increase the probability of recruitment within the landscape neighborhood during at least some years and at some ponds, and to increase the likelihood of interpond movement.
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ULTRAESTRUCTURA DE LA GÓNADA DEL MACHO DE DOS SUBESPECIES DE Bufo longinasus
Directory of Open Access Journals (Sweden)
Ana Sanz-Ochotorena
2009-01-01
organización quística, es decir, forman grupos de células asociadas a las células de Sertoli, que son los cistos espermatogenéticos o espermatocistos dentro de los túbulos seminíferos. Los espermatozoides se caracterizan por una extraordinaria compactación nuclear y se observó la presencia de una membrana ondulante.
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Hu, Junzheng; Cui, Weiding; Ding, Wenxiao; Gu, Yanqing; Wang, Zhen; Fan, Weimin
2017-01-01
Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN), secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. H2O2 (400 µM)-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL). gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of H2O2-induced chondrocytes apoptosis by gAPN. g
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Directory of Open Access Journals (Sweden)
Junzheng Hu
2017-08-01
Full Text Available Background/Aims: Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN, secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. Methods: H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. Results: H2O2 (400 µM-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL. gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of
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Wang, Xin; Xu, Mei; Frank, Jacqueline A; Ke, Zun-Ji; Luo, Jia
2017-04-01
Thiamine (vitamin B1) deficiency (TD) plays a major role in the etiology of Wernicke's encephalopathy (WE) which is a severe neurological disorder. TD induces selective neuronal cell death, neuroinflammation, endoplasmic reticulum (ER) stress and oxidative stress in the brain which are commonly observed in many aging-related neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD) and progressive supranuclear palsy (PSP). However, the underlying cellular and molecular mechanisms remain unclear. The progress in this line of research is hindered due to the lack of appropriate in vitro models. The neurons derived for the human induced pluripotent stem cells (hiPSCs) provide a relevant and powerful tool for the research in pharmaceutical and environmental neurotoxicity. In this study, we for the first time used human induced pluripotent stem cells (hiPSCs)-derived neurons (iCell neurons) to investigate the mechanisms of TD-induced neurodegeneration. We showed that TD caused a concentration- and duration-dependent death of iCell neurons. TD induced ER stress which was evident by the increase in ER stress markers, such as GRP78, XBP-1, CHOP, ATF-6, phosphorylated eIF2α, and cleaved caspase-12. TD also triggered oxidative stress which was shown by the increase in the expression 2,4-dinitrophenyl (DNP) and 4-hydroxynonenal (HNE). ER stress inhibitors (STF-083010 and salubrinal) and antioxidant N-acetyl cysteine (NAC) were effective in alleviating TD-induced death of iCell neurons, supporting the involvement of ER stress and oxidative stress. It establishes that the iCell neurons are a novel tool to investigate cellular and molecular mechanisms for TD-induced neurodegeneration. Copyright © 2017 Elsevier Inc. All rights reserved.
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Yamazaki, Tomomi; Nakamori, Akiko; Sasaki, Eriko; Wada, Satoshi; Ezaki, Osamu
2007-12-01
Diets high in sucrose/fructose or fat can result in hepatic steatosis (fatty liver). We analyzed the effects of dietary fish oil on fatty liver induced by sucrose, safflower oil, and butter in ddY mice. In experiment I, mice were fed a high-starch diet [70 energy% (en%) starch] plus 20% (wt/wt) sucrose in the drinking water or fed a high-safflower oil diet (60 en%) for 11 weeks. As a control, mice were fed a high-starch diet with drinking water. Fish oil (10 en%) was either supplemented or not. Mice supplemented with sucrose or fed safflower oil showed a 1.7-fold or 2.2-fold increased liver triglyceride content, respectively, compared with that of control mice. Fish oil completely prevented sucrose-induced fatty liver, whereas it exacerbated safflower oil-induced fatty liver. Sucrose increased SREBP-1c and target gene messenger RNAs (mRNAs), and fish oil completely inhibited these increases. In experiment II, mice were fed a high-safflower oil or a high-butter diet, with or without fish oil supplementation. Fish oil exacerbated safflower oil-induced fatty liver but did not affect butter-induced fatty liver. Fish oil increased expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and target CD36 mRNA in safflower oil-fed mice. These increases were not observed in sucrose-supplemented or butter-fed mice. The effects of dietary fish oil on fatty liver differ according to the cause of fatty liver; fish oil prevents sucrose-induced fatty liver but exacerbates safflower oil-induced fatty liver. The exacerbation of fatty liver may be due, at least in part, to increased expression of liver PPARgamma.
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Spaceflight-Induced Intracranial Hypertension.
Michael, Alex P; Marshall-Bowman, Karina
2015-06-01
Although once a widely speculated about and largely theoretical topic, spaceflight-induced intracranial hypertension has gained acceptance as a distinct clinical phenomenon, yet the underlying physiological mechanisms are still poorly understood. In the past, many terms were used to describe the symptoms of malaise, nausea, vomiting, and vertigo, though longer duration spaceflights have increased the prevalence of overlapping symptoms of headache and visual disturbance. Spaceflight-induced visual pathology is thought to be a manifestation of increased intracranial pressure (ICP) because of its similar presentation to cases of known intracranial hypertension on Earth as well as the documentation of increased ICP by lumbar puncture in symptomatic astronauts upon return to gravity. The most likely mechanisms of spaceflight-induced increased ICP include a cephalad shift of body fluids, venous outflow obstruction, blood-brain barrier breakdown, and disruption to CSF flow. The relative contribution of increased ICP to the symptoms experienced during spaceflight is currently unknown, though other factors recently posited to contribute include local effects on ocular structures, individual differences in metabolism, and the vasodilator effects of carbon dioxide. This review article attempts to consolidate the literature regarding spaceflight-induced intracranial hypertension and distinguish it from other pathologies with similar symptomatology. It discusses the proposed physiological causes and the pathological manifestations of increased ICP in the spaceflight environment and provides considerations for future long-term space travel. In the future, it will be critical to develop countermeasures so that astronauts can participate at their peak potential and return safely to Earth.
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Mutations induced in plant breeding
International Nuclear Information System (INIS)
Barriga B, P.
1984-01-01
The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented. (Author)
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Mutations induced in plant breeding
Energy Technology Data Exchange (ETDEWEB)
Barriga B, P. (Universidad Austral de Chile, Valdivia. Inst. de Produccion y Sanidad Vegetal)
1984-10-01
The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented.
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Non-equilibrium fluctuation-induced interactions
International Nuclear Information System (INIS)
Dean, David S
2012-01-01
We discuss non-equilibrium aspects of fluctuation-induced interactions. While the equilibrium behavior of such interactions has been extensively studied and is relatively well understood, the study of these interactions out of equilibrium is relatively new. We discuss recent results on the non-equilibrium behavior of systems whose dynamics is of the dissipative stochastic type and identify a number of outstanding problems concerning non-equilibrium fluctuation-induced interactions.
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Trauma hemorrhagic shock-induced lung injury involves a gut-lymph-induced TLR4 pathway in mice.
Directory of Open Access Journals (Sweden)
Diego C Reino
Full Text Available Injurious non-microbial factors released from the stressed gut during shocked states contribute to the development of acute lung injury (ALI and multiple organ dysfunction syndrome (MODS. Since Toll-like receptors (TLR act as sensors of tissue injury as well as microbial invasion and TLR4 signaling occurs in both sepsis and noninfectious models of ischemia/reperfusion (I/R injury, we hypothesized that factors in the intestinal mesenteric lymph after trauma hemorrhagic shock (T/HS mediate gut-induced lung injury via TLR4 activation.The concept that factors in T/HS lymph exiting the gut recreates ALI is evidenced by our findings that the infusion of porcine lymph, collected from animals subjected to global T/HS injury, into naïve wildtype (WT mice induced lung injury. Using C3H/HeJ mice that harbor a TLR4 mutation, we found that TLR4 activation was necessary for the development of T/HS porcine lymph-induced lung injury as determined by Evan's blue dye (EBD lung permeability and myeloperoxidase (MPO levels as well as the induction of the injurious pulmonary iNOS response. TRIF and Myd88 deficiency fully and partially attenuated T/HS lymph-induced increases in lung permeability respectively. Additional studies in TLR2 deficient mice showed that TLR2 activation was not involved in the pathology of T/HS lymph-induced lung injury. Lastly, the lymph samples were devoid of bacteria, endotoxin and bacterial DNA and passage of lymph through an endotoxin removal column did not abrogate the ability of T/HS lymph to cause lung injury in naïve mice.Our findings suggest that non-microbial factors in the intestinal mesenteric lymph after T/HS are capable of recreating T/HS-induced lung injury via TLR4 activation.
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Directory of Open Access Journals (Sweden)
Kenji Takemoto
2014-01-01
Full Text Available Excessive acetaminophen (APAP use is one of the most common causes of acute liver failure. Various types of cell death in the damaged liver are linked to APAP-induced hepatotoxicity, and, of these, necrotic cell death of hepatocytes has been shown to be involved in disease pathogenesis. Until recently, necrosis was commonly considered to be a random and unregulated form of cell death; however, recent studies have identified a previously unknown form of programmed necrosis called receptor-interacting protein kinase (RIPK-dependent necrosis (or necroptosis, which is controlled by the kinases RIPK1 and RIPK3. Although RIPK-dependent necrosis has been implicated in a variety of disease states, including atherosclerosis, myocardial organ damage, stroke, ischemia–reperfusion injury, pancreatitis, and inflammatory bowel disease. However its involvement in APAP-induced hepatocyte necrosis remains elusive. Here, we showed that RIPK1 phosphorylation, which is a hallmark of RIPK-dependent necrosis, was induced by APAP, and the expression pattern of RIPK1 and RIPK3 in the liver overlapped with that of CYP2E1, whose activity around the central vein area has been demonstrated to be critical for the development of APAP-induced hepatic injury. Moreover, a RIPK1 inhibitor ameliorated APAP-induced hepatotoxicity in an animal model, which was underscored by significant suppression of the release of hepatic enzymes and cytokine expression levels. RIPK1 inhibition decreased reactive oxygen species levels produced in APAP-injured hepatocytes, whereas CYP2E1 expression and the depletion rate of total glutathione were unaffected. Of note, RIPK1 inhibition also conferred resistance to oxidative stress in hepatocytes. These data collectively demonstrated a RIPK-dependent necrotic mechanism operates in the APAP-injured liver and inhibition of this pathway may be beneficial for APAP-induced fulminant hepatic failure.
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The role of natural and UV-induced skin pigmentation on low-fluence IPL-induced side effects
DEFF Research Database (Denmark)
Thaysen-Petersen, Daniel; Lin, Jennifer Y; Nash, Jf
2014-01-01
BACKGROUND AND OBJECTIVES: The risk of adverse skin effects following light-based hair removal is greater in pigmented skin based on the theory of selective photothermolysis. Thus sunlight-induced pigment i.e., facultative pigmentation, increases the risk of adverse skin effects, perhaps dispropo...... pigmentation regardless of the origin, i.e., constitutive versus UV induced....
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On the reliability of retrieval-induced forgetting
Directory of Open Access Journals (Sweden)
Christopher eRowland
2014-11-01
Full Text Available Memory is modified through the act of retrieval. Although retrieving a target piece of information may strengthen the retrieved information itself, it may also serve to weaken retention of related information. This phenomenon, termed retrieval-induced forgetting, has garnered substantial interest for its implications as to why forgetting occurs. The present study attempted to replicate the seminal work by Anderson, Bjork, and Bjork (1994 on retrieval-induced forgetting, given the apparent sensitivity of the effect to certain deviations from the original paradigm developed to study the phenomenon. The study extends the conditions under which retrieval-induced forgetting has been examined by utilizing both a traditional college undergraduate sample (Experiment 1, along with a more diverse internet sample (Experiment 2. In addition, Experiment 3 details a replication attempt of retrieval-induced forgetting using Anderson and Spellman’s (1995 independent cue procedure. Retrieval-induced forgetting was observed when using the traditional retrieval practice paradigm with undergraduate (Experiment 1 and internet (Experiment 2 samples, though the effect was not found when using the independent cue procedure (Experiment 3. Thus, the study can provide an indication as to the robustness of retrieval-induced forgetting to deviations from the traditional college undergraduate samples that have been used in the majority of existing research on the effect.
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Lithium protects ethanol-induced neuronal apoptosis
International Nuclear Information System (INIS)
Zhong Jin; Yang Xianlin; Yao Weiguo; Lee Weihua
2006-01-01
Lithium is widely used for the treatment of bipolar disorder. Recent studies have demonstrated its neuroprotective effect. Ethanol is a potent neurotoxin that is particularly harmful to the developing nervous system. In this study, we evaluated lithium's neuroprotection against ethanol-induced apoptosis. Transient exposure of infant mice to ethanol caused apoptotic cell death in brain, which was prevented significantly by administering a low dose of lithium 15 min later. In cultured cerebellar granule neurons, ethanol-induced apoptosis and activation of caspase-3/9, both of which were prevented by lithium. However, lithium's protection is not mediated by its commonly known inhibition of glycogen synthase3β, because neither ethanol nor lithium has significant effects on the phosphorylation of Akt (ser473) or GSK3β (ser9). In addition, the selective GSK-3β inhibitor SB-415286 was unable to prevent ethanol-induced apoptosis. These data suggest lithium may be used as a potential preventive measure for ethanol-induced neurological deficits
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Ionizing radiation induced malignancies in man
International Nuclear Information System (INIS)
Dutrillaux, B.
1997-01-01
Using data on gene and chromosome alterations in human cancers, it is proposed that most radiation induced cancers are a consequence of recessive mutations of tumor suppressor genes. This explains the long delay between radiation exposure and the cancer onset. As a consequence, radiation induced cancers belong to groups of tumors where no specific translocations (forming or activating oncogenes) but multiple unbalanced chromosome rearrangements (deletions unmasking recessive mutations) exist. This explains why osteosarcomas, malignant fibrous histiocytoma, chondrosarcomas are frequently induced, but not liposarcoma, Ewing sarcomas and rhabdomyosarcomas, among others. A single exception confirms this rule: papillary thyroid cancer, frequently induced in exposed children, in which structural rearrangements frequently form a RET/PTC3 fusion gene. This fusion gene is the results of the inversion of a short segment of chromosome 10, and it is assumed that such rearrangement (small para-centric inversion) can easily occur after exposure to radiations, at contrast with translocations between to genes belonging to different chromosomes. (author)
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Qiang, Guifen; Kong, Hyerim Whang; Fang, Difeng; McCann, Maximilian; Yang, Xiuying; Du, Guanhua; Blüher, Matthias; Zhu, Jinfang; Liew, Chong Wee
2016-04-25
The intimate link between location of fat accumulation and metabolic disease risk and depot-specific differences is well established, but how these differences between depots are regulated at the molecular level remains largely unclear. Here we show that TRIP-Br2 mediates endoplasmic reticulum (ER) stress-induced inflammatory responses in visceral fat. Using in vitro, ex vivo and in vivo approaches, we demonstrate that obesity-induced circulating factors upregulate TRIP-Br2 specifically in visceral fat via the ER stress pathway. We find that ablation of TRIP-Br2 ameliorates both chemical and physiological ER stress-induced inflammatory and acute phase response in adipocytes, leading to lower circulating levels of inflammatory cytokines. Using promoter assays, as well as molecular and pharmacological experiments, we show that the transcription factor GATA3 is responsible for the ER stress-induced TRIP-Br2 expression in visceral fat. Taken together, our study identifies molecular regulators of inflammatory response in visceral fat that-given that these pathways are conserved in humans-might serve as potential therapeutic targets in obesity.
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Angiogenic effect induced by mineral fibres
International Nuclear Information System (INIS)
Carbonari, Damiano; Campopiano, Antonella; Ramires, Deborah; Strafella, Elisabetta; Staffolani, Sara; Tomasetti, Marco; Curini, Roberta; Valentino, Matteo; Santarelli, Lory; Amati, Monica
2011-01-01
Highlights: → In this study we described the angiogenetic effect of some mineral fibres. → Wollastonite fibres induce blood vessel formation. → The size and shape of the fibres were important factors for the cell signalling. → Wollastonite induce ROS-NFκB activation and EGFR signalling. → Involvement of wollastonite exposure in the development of pathological conditions. -- Abstract: Due to the toxic effect of asbestos, other materials with similar chemical-physical characteristics have been introduced to substitute it. We evaluate the angiogenic effect of certain asbestos substitute fibres such as glass fibres (GFs), ceramic fibres (CFs) and wollastonite fibres (WFs) and then compare angiogenic responses to those induced by crocidolite asbestos fibres (AFs). An in vitro model using human endothelial cells in small islands within a culture matrix of fibroblasts (Angio-Kit) was used to evaluate vessel formation. The release of IL-6, sIL-R6, IL-8, VEGF-A and their soluble receptors, sVEGFR-1, sVEGFR-2, was determined in the conditioning medium of Angio-Kit system after fibre treatment. ROS formation and cell viability were evaluated in cultured endothelial cells (HUVEC). To evaluate the involvement of intracellular mechanisms, EGFR signalling, ROS formation and nuclear factor-κB (NFκB) pathway were then inhibited by incubating HUVEC cells with AG1478, NAC and PDTC respectively, and the cytokine and growth factor release was analyzed in the culture medium after 7 days of fibre incubation. Among the mineral fibres tested, WFs markedly induced blood vessel formation which was associated with release of IL-6 and IL-8, VEGF-A and their soluble receptors. ROS production was observed in HUVEC after WFs treatment which was associated with cell cytotoxicity. The EGFR-induced ERK phosphorylation and ROS-mediated NFκB activation were involved in the cytokine and angiogenic factor release. However, only the EGFR activation was able to induce angiogenesis. The WFs
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Airbag induced corneal ectasia.
Mearza, Ali A; Koufaki, Fedra N; Aslanides, Ioannis M
2008-02-01
To report a case of airbag induced corneal ectasia. Case report. A patient 3 years post-LASIK developed bilateral corneal ectasia worse in the right eye following airbag deployment in a road traffic accident. At last follow up, best corrected vision was 20/40 with -4.00/-4.00 x 25 in the right eye and 20/25 with -1.25/-0.50 x 135 in the left eye. This is a rare presentation of trauma induced ectasia in a patient post-LASIK. It is possible that reduction in biomechanical integrity of the cornea from prior refractive surgery contributed to this presentation.
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Electron-irradiation-induced phase transformation in alumina
International Nuclear Information System (INIS)
Chen, C.L.; Arakawa, K.; Lee, J.-G.; Mori, H.
2010-01-01
In this study, electron-irradiation-induced phase transformations between alumina polymorphs were investigated by high-resolution transmission electron microscopy. It was found that the electron-irradiation-induced α → κ' phase transformation occurred in the alumina under 100 keV electron irradiation. It is likely that the knock-on collision between incident electrons and Al 3+ cations is responsible for the occurrence of electron-irradiation-induced phase transformation from α-alumina to κ'-alumina.
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Flow-induced elastic anisotropy of metallic glasses
International Nuclear Information System (INIS)
Sun, Y.H.; Concustell, A.; Carpenter, M.A.; Qiao, J.C.; Rayment, A.W.; Greer, A.L.
2016-01-01
As-cast bulk metallic glasses are isotropic, but anisotropy can be induced by thermomechanical treatments. For example, the diffraction halo in the structure function S(Q) observed in transmission becomes elliptical (rather than circular) after creep in uniaxial tension or compression. Published studies associate this with frozen-in anelastic strain and bond-orientational anisotropy. Results so far are inconsistent on whether viscoplastic flow of metallic glasses can induce anisotropy. Preliminary diffraction data suggest that the anisotropy, if any, is very low, while measurements of the elastic properties suggest that there is induced anisotropy, opposite in sign to that due to anelastic strain. We study three bulk metallic glasses, Ce 65 Al 10 Cu 20 Co 5 , La 55 Ni 10 Al 35 , and Pd 40 Ni 30 Cu 10 P 20 . By using resonant ultrasound spectroscopy to determine the full elasticity tensor, the effects of relaxation and rejuvenation can be reliably separated from uniaxial anisotropy (of either sign). The effects of viscoplastic flow in tension are reported for the first time. We find that viscoplastic flow of bulk metallic glasses, particularly in tension, can induce significant anisotropy that is distinct from that associated with frozen-in anelastic strain. The conditions for inducing such anisotropy are explored in terms of the Weissenberg number (ratio of relaxation times for primary relaxation and for shear strain rate). There is a clear need for further work to characterize the structural origins of flow-induced anisotropy and to explore the prospects for improved mechanical and other properties through induced anisotropy.
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Aspirin-induced asthma in children.
Botey, J; Navarro, C; Marín, A; Eseverri, J L
1988-01-01
Since Cooke first described bronchospasm induced by acetyl salicylic acid in asthmatic patients in 1919, numerous studies have been done with the objective of understanding the pathology, treatment and incidence of aspirin-induced asthma. The incidence is difficult to establish but according to two recent studies, the percentage in the infantile asthmatic population was estimated at 13% and 28%. This prevalence is greater than that suspected at first and reveals the necessity of reviewing this problem. In this study we present 4 pediatric patients, 2 atopics and 2 non-atopics affected with aspirin-induced asthma. A detailed clinical history, oral provocation test to acetyl salicylic acid, other non-steroid anti-inflammatory analgesics and additives was performed. The oral provocation test with acetyl salicylic acid was positive in all 4 cases. The oral provocation with non-steroid anti-inflammatory analgesics and other additives was negative in 2 patients. In the remaining 2 patients, one demonstrated sensitivity only to tartrazine and the other to tartrazine, red coccine, mefenamic acid and benorylate. In conclusion, aspirin-induced asthma is not infrequent in infancy. Therefore, it is important to bear it always in mind and to diagnose it through oral provocation besides looking for possible cross reactions.
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The sound-induced phosphene illusion.
Bolognini, Nadia; Convento, Silvia; Fusaro, Martina; Vallar, Giuseppe
2013-12-01
Crossmodal illusions clearly show how perception, rather than being a modular and self-contained function, can be dramatically altered by interactions between senses. Here, we provide evidence for a novel crossmodal "physiological" illusion, showing that sounds can boost visual cortical responses in such a way to give rise to a striking illusory visual percept. In healthy participants, a single-pulse transcranial magnetic stimulation (sTMS) delivered to the occipital cortex evoked a visual percept, i.e., a phosphene. When sTMS is accompanied by two auditory beeps, the second beep induces in neurologically unimpaired participants the perception of an illusory second phosphene, namely the sound-induced phosphene illusion. This perceptual "fission" of a single phosphene, due to multiple beeps, is not matched by a "fusion" of double phosphenes due to a single beep, and it is characterized by an early auditory modulation of the TMS-induced visual responses (~80 ms). Multiple beeps also induce an illusory feeling of multiple TMS pulses on the participants' scalp, consistent with an audio-tactile fission illusion. In conclusion, an auditory stimulation may bring about a phenomenological change in the conscious visual experience produced by the transcranial stimulation of the occipital cortex, which reveals crossmodal binding mechanisms within early stages of visual processing.
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Aphrodisiacs past and present: a historical review.
Sandroni, P
2001-10-01
The drug Viagra (sildenafil) has drawn public attention to aphrodisiacs. The search for such substances dates back millennia. Aphrodisiacs can be classified by their mode of action into 3 types: those that increase (1) libido, (2) potency, or (3) sexual pleasure. Various substances of animal and plant origin have been used in folk medicines of different cultures; some have been identified pharmacologically, allowing for understanding of their mechanisms of action. For increasing libido, ambrein, a major constituent of Ambra grisea, is used in Arab countries. This tricyclic triterpene alcohol increases the concentration of several anterior pituitary hormones and serum testosterone. Bufo toad skin and glands contain bufotenine (and other bufadienolides), a putative hallucinogenic congener of serotonin. It is the active ingredient in West Indian "love stone" and the Chinese medication chan su. The aphrodisiac properties are likely of central origin, as are the other effects of the drug. For increasing potency, Panax ginseng used in traditional Chinese medicine, works as an antioxidant by enhancing nitric oxide synthesis in the endothelium of many organs, including the corpora cavernosa; ginsenosides also enhance acetylcholine-induced and transmural nerve stimulation-activated relaxation associated with increased tissue cyclic guanosine monophosphate, hence the aphrodisiac properties. For increasing sexual pleasure, cantharidin ("Spanish fly") is a chemical with vesicant properties derived from blister beetles, which have been used for millennia as a sexual stimulant. Its mode of action is by inhibition of phosphodiesterase and protein phosphatase activity and stimulation of beta-receptors, inducing vascular congestion and inflammation. Morbidity from its abuse is significant. The ingestion of live beetles (Palembus dermestoides) in Southeast Asia and triatomids in Mexico may have a basis similar to cantharidin. It is of paramount importance for the physician to be
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Uterine contraction induced by Ghanaian plants used to induce abortion
DEFF Research Database (Denmark)
Larsen, Birgitte HV; Soelberg, Jens; Kristiansen, Uffe
2016-01-01
Ethnomedicinal observations from the time of the Atlantic slave trade show women in Ghana historically used plants as emmenagogues (menstruation stimulants) and to induce abortion. This study investigates the effect of four of these plants on uterine contraction. The historically used plants were...
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Factors associated with repeat induced abortion in Kenya.
Maina, Beatrice W; Mutua, Michael M; Sidze, Estelle M
2015-10-12
Over six million induced abortions were reported in Africa in 2008 with over two million induced abortions occurring in Eastern Africa. Although a significant proportion of women in the region procure more than one abortion during their reproductive period, there is a dearth of research on factors associated with repeat abortion. Data for this study come from the Magnitude and Incidence of Unsafe Abortion Study conducted by the African Population and Health Research Center in Kenya in 2012. The study used a nationally-representative sample of 350 facilities (level II to level VI) that offer post-abortion services for complications following induced and spontaneous abortions. A prospective morbidity survey tool was used by health providers in 328 facilities to collect information on socio-demographic charateristics, reproductive health history and contraceptive use at conception for all patients presenting for post-abortion services. Our analysis is based on data recorded on 769 women who were classified as having had an induced abortion. About 16 % of women seeking post abortion services for an induced abortion reported to have had a previous induced abortion. Being separated or divorced or widowed, having no education, having unwanted pregnancy, having 1-2 prior births and using traditional methods of contraception were associated with a higher likelihood of a repeat induced abortion. The findings point to the need to address the reasons why women with first time induced abortion do not have the necessary information to prevent unintended pregnancies and further induced abortions. Possible explanations linked to the quality of post-abortion family planning and coverage of long-acting methods should be explored.
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International Nuclear Information System (INIS)
Chen Rui; Han Jian-Wei; Zheng Han-Sheng; Yu Yong-Tao; Shangguang Shi-Peng; Feng Guo-Qiang; Ma Ying-Qi
2015-01-01
By using the pulsed laser single event effect facility and electro-static discharge (ESD) test system, the characteristics of the “high current”, relation with external stimulus and relevance to impacted modes of single event latch-up (SEL) and transient-induced latch-up (TLU) are studied, respectively, for a 12-bit complementary metal–oxide semiconductor (CMOS) analog-to-digital converter. Furthermore, the sameness and difference in physical mechanism between “high current” induced by SEL and that by TLU are disclosed in this paper. The results show that the minority carrier diffusion in the PNPN structure of the CMOS device which initiates the active parasitic NPN and PNP transistors is the common reason for the “high current” induced by SEL and for that by TLU. However, for SEL, the minority carrier diffusion is induced by the ionizing radiation, and an underdamped sinusoidal voltage on the supply node (the ground node) is the cause of the minority carrier diffusion for TLU. (paper)
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Alves, Ingrid R; Lima-Noronha, Marco A; Silva, Larissa G; Fernández-Silva, Frank S; Freitas, Aline Luiza D; Marques, Marilis V; Galhardo, Rodrigo S
2017-11-01
imuABC (imuAB dnaE2) genes are responsible for SOS-mutagenesis in Caulobacter crescentus and other bacterial species devoid of umuDC. In this work, we have constructed operator-constitutive mutants of the imuABC operon. We used this genetic tool to investigate the effect of SOS-induced levels of these genes upon both spontaneous and damage-induced mutagenesis. We showed that constitutive expression of imuABC does not increase spontaneous or damage-induced mutagenesis, nor increases cellular resistance to DNA-damaging agents. Nevertheless, the presence of the operator-constitutive mutation rescues mutagenesis in a recA background, indicating that imuABC are the only genes required at SOS-induced levels for translesion synthesis (TLS) in C. crescentus. Furthermore, these data also show that TLS mediated by ImuABC does not require RecA, unlike umuDC-dependent mutagenesis in E. coli. Copyright © 2017 Elsevier B.V. All rights reserved.
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Luger, Anna-Luisa; Sauer, Benedikt; Lorenz, Nadja I; Engel, Anna L; Braun, Yannick; Voss, Martin; Harter, Patrick N; Steinbach, Joachim P; Ronellenfitsch, Michael W
2018-05-17
Inducible gene expression is an important tool in molecular biology research to study protein function. Most frequently, the antibiotic doxycycline is used for regulation of so-called tetracycline (Tet)-inducible systems. In contrast to stable gene overexpression, these systems allow investigation of acute and reversible effects of cellular protein induction. Recent reports have already called for caution when using Tet-inducible systems as the employed antibiotics can disturb mitochondrial function and alter cellular metabolism by interfering with mitochondrial translation. Reprogramming of energy metabolism has lately been recognized as an important emerging hallmark of cancer and is a central focus of cancer research. Therefore, the scope of this study was to systematically analyze dose-dependent metabolic effects of doxycycline on a panel of glioma cell lines with concomitant monitoring of gene expression from Tet-inducible systems. We report that doxycycline doses commonly used with inducible expression systems (0.01⁻1 µg/mL) substantially alter cellular metabolism: Mitochondrial protein synthesis was inhibited accompanied by reduced oxygen and increased glucose consumption. Furthermore, doxycycline protected human glioma cells from hypoxia-induced cell death. An impairment of cell growth was only detectable with higher doxycycline doses (10 µg/mL). Our findings describe settings where doxycycline exerts effects on eukaryotic cellular metabolism, limiting the employment of Tet-inducible systems.
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Modulation of 17{beta}-estradiol-induced responses in fish by cytochrome P4501A1 inducing compounds
Energy Technology Data Exchange (ETDEWEB)
Anderson, M.J.; Hinton, D.E. [Univ. of California, Davis, CA (United States)
1995-12-31
Some compounds which induce cytochrome P4501A1 (CYP1A1) are antiestrogenic in mammalian bioassay, and this effect is linked to aryl hydrocarbon (Ah) receptor. Liver of fish synthesizes estrogen-inducible egg yolk precursor protein vitellogenin (Vg) which is critical for oocyte maturation and ovarian development. To determine if Ah receptor-linked endocrine modulation could occur in fish liver, primary cultures of juvenile rainbow trout (Oncorhynchus mykiss) liver cells were co-administered 17{beta}-estradiol and CYP1A1 inducing compounds. Vitellogenin and albumin, estimated by ELISA measurement of concentration in the media 48 hrs after treatment, formed the basis for the test. Cellular CYP1A1 protein content and catalytic activity was estimated by ELISA and ethoxyresorufin-O-deethylase (EROD) activity assays respectively. Equivalent viability (mitochondrial dehydrogenase activity) and secretary functional capacity (albumin synthesis) were estimated and correlated with other results. In descending order, 2,3,4,7,8 pentachlorodibenzofuran (10{sup {minus}12} to 10{sup {minus}8} M) > 2,3,7,8 tetrachlorodibenzo-p-dioxin {approx_equal} 2,3,7,8 tetrachlorodibenzofuran (10{sup {minus}11} to 10{sup {minus}8} M) > {beta}-naphthoflavone (10{sup {minus}7} to 10{sup {minus}6} M) inhibited Vg synthesis in 17{beta}-estradiol treated liver cells. Potency of inhibition directly related to strength as an inducer of CYP1A1 protein. At 10-8 M, PCB congeners 77, 126, and 156 did not inhibit Vg synthesis and induced no or only moderate CYP1A1 protein. At 10-8 M, PCB congener 114, a weak CYP1A1 inducer, potentiated Vg synthesis relative to cells treated with 17{beta}-estradiol alone. This study increases their understanding of the consequences of hepatic CYP1A1 induction, forewarns of reproductive impairment of sexually maturing fishes exposed to CYP1A1 inducing compounds and argues for further, more detailed in vivo investigation.
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Nonacetaminophen Drug-Induced Acute Liver Failure.
Thomas, Arul M; Lewis, James H
2018-05-01
Acute liver failure of all causes is diagnosed in between 2000 and 2500 patients annually in the United States. Drug-induced acute liver failure is the leading cause of acute liver failure, accounting for more than 50% of cases. Nonacetaminophen drug injury represents 11% of all cases in the latest registry from the US Acute Liver Failure Study Group. Although rare, acute liver failure is clinically dramatic when it occurs, and requires a multidisciplinary approach to management. In contrast with acetaminophen-induced acute liver failure, non-acetaminophen-induced acute liver failure has a more ominous prognosis with a lower liver transplant-free survival. Copyright © 2018 Elsevier Inc. All rights reserved.
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Radiation-induced centers in inorganic glasses
International Nuclear Information System (INIS)
Brekhovskikh, S.M.; Tyul'nin, V.A.
1988-01-01
The nature, structure and formation mechanisms of radiation-induced colour centers, EPR, luminescence, generated ionizing radiation in nonorganic oxide glasses are considered. Experimental material covering both fundamental aspects of radiation physics and glass chemistry, and aspects intimately connected with the creation of new materials with the given radiation-spectral characteristics, with possibilities to prepare radiation-stable and radiation-sensitive glasses is systematized and generalized. Considerable attention is paid to the detection of radiation-induced center binding with composition, glass structures redox conditions for their synthesis. Some new possibilities of practical application of glasses with radiation-induced centers, in particular, to record optical information are reflected in the paper
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International Nuclear Information System (INIS)
Banerjee, Chaitali; Goswami, Ramansu; Datta, Soma; Rajagopal, R.; Mazumder, Shibnath
2011-01-01
We had earlier shown that exposure to arsenic (0.50 μM) caused caspase-3 mediated head kidney macrophage (HKM) apoptosis involving the p38-JNK pathway in Clarias batrachus. Here we examined the roles of calcium (Ca 2+ ) and extra-cellular signal-regulated protein kinase (ERK), the other member of MAPK-pathway on arsenic-induced HKM apoptosis. Arsenic-induced HKM apoptosis involved increased expression of ERK and calpain-2. Nifedipine, verapamil and EGTA pre-treatment inhibited the activation of calpain-2, ERK and reduced arsenic-induced HKM apoptosis as evidenced from reduced caspase-3 activity, Annexin V-FITC-propidium iodide and Hoechst 33342 staining. Pre-incubation with ERK inhibitor U 0126 inhibited the activation of calpain-2 and interfered with arsenic-induced HKM apoptosis. Additionally, pre-incubation with calpain-2 inhibitor also interfered with the activation of ERK and inhibited arsenic-induced HKM apoptosis. The NADPH oxidase inhibitor apocynin and diphenyleneiodonium chloride also inhibited ERK activation indicating activation of ERK in arsenic-exposed HKM also depends on signals from NADPH oxidase pathway. Our study demonstrates the critical role of Ca 2+ homeostasis on arsenic-induced HKM apoptosis. We suggest that arsenic-induced alteration in intracellular Ca 2+ levels initiates pro-apoptotic ERK and calpain-2; the two pathways influence each other positively and induce caspase-3 mediated HKM apoptosis. Besides, our study also indicates the role of ROS in the activation of ERK pathway in arsenic-induced HKM apoptosis in C. batrachus. - Highlights: → Altered Ca 2+ homeostasis leads to arsenic-induced HKM apoptosis. → Calpain-2 plays a critical role in the process. → ERK is pro-apoptotic in arsenic-induced HKM apoptosis. → Arsenic-induced HKM apoptosis involves cross talk between calpain-2 and ERK.
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Overexpression of BAG3 Attenuates Hypoxia-Induced Cardiomyocyte Apoptosis by Inducing Autophagy.
Zhang, Jiankai; He, Zhangyou; Xiao, Wenjian; Na, Qingqing; Wu, Tianxiu; Su, Kaixin; Cui, Xiaojun
2016-01-01
Hypoxia is a well-known factor in the promotion of apoptosis, which contributes to the development of numerous cardiac diseases, such as heart failure and myocardial infarction. Inhibiting apoptosis is an important therapeutic strategy for the treatment of related heart diseases caused by ischemia/hypoxic injury. Previous studies have demonstrated that BAG3 plays an important role in cardiomyocyte apoptosis and survival. However, the role of BAG3 in hypoxia-induced cardiomyocyte apoptosis remains to be clarified. Here, we demonstrate that BAG3 is induced by hypoxia stimuli in cultured cardiomyocytes. BAG3 expression level was measured in H9c2 cells treated with hypoxia for 48 h. Cell proliferation and apoptosis were tested using MTT assay and Annexin V FITC-PI staining assay, respectively. The mRNA or protein expression level of BAG3, LC3-I, LC3-II, Atg5, NF-x03BA;B p65 and phosphorylated NF-x03BA;B p65 were assessed by qRT-PCR and western blot assay, respectively. Resluts: Overexpression of BAG3 inhibited cell apoptosis and promoted proliferation in hypoxia-injured H9c2 cells. Furthermore, autophagy and NF-x03BA;B were activated by BAG3 overexpression, and the NF-x03BA;B inhibitor PDTC could inhibit the activation of autophagy induced by BAG3 overexpression. In addition, the autophagy inhibitor 3-MA partly impeded the inhibitory effect of BAG3 on hypoxia-induced cardiomyocyte apoptosis. these results suggested that overexpression of BAG3 promoted cell proliferation and inhibited apoptosis by activating autophagy though the NF-x03BA;B signaling pathway in hypoxia-injured cardiomyocytes. © 2016 The Author(s) Published by S. Karger AG, Basel.
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Mao, Yun; Luo, Wei; Zhang, Lin; Wu, Weiwei; Yuan, Liangshuai; Xu, Hao; Song, Juhee; Fujiwara, Keigi; Abe, Jun-ichi; LeMaire, Scott A.; Wang, Xing Li; Shen, Ying. H.
2017-01-01
Objective Metabolic stress in obesity induces endothelial inflammation and activation, which initiates adipose tissue inflammation, insulin resistance, and cardiovascular diseases. However, the mechanisms underlying endothelial inflammation induction are not completely understood. Stimulator of interferon genes (STING) is an important molecule in immunity and inflammation. In the present study, we sought to determine the role of STING in palmitic acid (PA)-induced endothelial activation/inflammation. Approach and Results In cultured endothelial cells, PA treatment activated STING, as indicated by its perinuclear translocation and binding to interferon regulatory factor 3 (IRF3), leading to IRF3 phosphorylation and nuclear translocation. The activated IRF3 bound to the promoter of intercellular adhesion molecule 1 (ICAM-1) and induced ICAM-1 expression and monocyte–endothelial cell adhesion. When analyzing the upstream signaling, we found that PA activated STING by inducing mitochondrial damage. PA treatment caused mitochondrial damage and leakage of mitochondrial DNA (mtDNA) into the cytosol. Through the cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS), the mitochondrial damage and leaked cytosolic mtDNA activated the STING-IRF3 pathway and increased ICAM-1 expression. In mice with diet-induced obesity, the STING-IRF3 pathway was activated in adipose tissue. However, STING deficiency (Stinggt/gt) partially prevented diet-induced adipose tissue inflammation, obesity, insulin resistance, and glucose intolerance. Conclusions The mitochondrial damage-cGAS-STING-IRF3 pathway is critically involved in metabolic stress-induced endothelial inflammation. STING may be a potential therapeutic target for preventing cardiovascular diseases and insulin resistance in obese individuals. PMID:28302626
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Han, Bing; Wang, Tong-Dan; Shen, Shao-Ming; Yu, Yun; Mao, Chan; Yao, Zhu-Jun; Wang, Li-Shun
2015-03-18
Annonaceous acetogenins are a family of natural products with antitumor activities. Annonaceous acetogenin mimic AA005 reportedly inhibits mammalian mitochondrial NADH-ubiquinone reductase (Complex I) and induces gastric cancer cell death. However, the mechanisms underlying its cell-death-inducing activity are unclear. We used SW620 colorectal adenocarcinoma cells to study AA005 cytotoxic activity. Cell deaths were determined by Trypan blue assay and flow cytometry, and related proteins were characterized by western blot. Immunofluorescence and subcellular fractionation were used to evaluate AIF nuclear translocation. Reactive oxygen species were assessed by using redox-sensitive dye DCFDA. AA005 induces a unique type of cell death in colorectal adenocarcinoma cells, characterized by lack of caspase-3 activation or apoptotic body formation, sensitivity to poly (ADP-ribose) polymerase inhibitor Olaparib (AZD2281) but not pan-caspase inhibitor Z-VAD.fmk, and dependence on apoptosis-inducing factor (AIF). AA005 treatment also reduced expression of mitochondrial Complex I components, and leads to accumulation of intracellular reactive oxygen species (ROS) at the early stage. Blocking ROS formation significantly suppresses AA005-induced cell death in SW620 cells. Moreover, blocking activation of RIP-1 by necroptosis inhibitor necrotatin-1 inhibits AIF translocation and partially suppresses AA005-induced cell death in SW620 cells demonstrating that RIP-1 protein may be essential for cell death. AA005 may trigger the cell death via mediated by AIF through caspase-3 independent pathway. Our work provided new mechanisms for AA005-induced cancer cell death and novel clues for cancer treatment via AIF dependent cell death.
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Park, Sung-Soo; Bae, Insoo; Lee, Yong J
2008-04-15
Hypoxia-inducible factor-1 alpha (HIF-1alpha) is the regulatory subunit of the heterodimeric transcription factor HIF-1 that is the key regulator of cellular response to low oxygen tension. Under normoxic conditions, HIF-1alpha is continuously degraded by the ubiquitin-proteasome pathway through pVHL (von Hippel-Lindau tumor suppressor protein). Under hypoxic conditions, HIF-1alpha is stabilized and induces the transcription of HIF-1 target genes. Quercetin, a flavonoid with anti-oxidant, anti-inflammatory, and kinase modulating properties, has been found to induce HIF-1alpha accumulation and VEGF secretion in normoxia. In this study, the molecular mechanisms of quercetin-mediated HIF-1alpha accumulation were investigated. Previous studies have shown that, in addition to being induced by hypoxia, HIF-1alpha can be induced through the phosphatidylinositol 3-kinase (PI3K)/Akt and p53 signaling pathways. But our study revealed, through p53 mutant-type as well as p53 null cell lines, that neither the PI3K/Akt nor the p53 signaling pathway is required for quercetin-induced HIF-1alpha accumulation. And we observed that HIF-1alpha accumulated by quercetin is not ubiquitinated and the interaction of HIF-1alpha with pVHL is reduced, compared with HIF-1alpha accumulated by the proteasome inhibitor MG132. The use of quercetin's analogues showed that only quercetin and galangin induce HIF-1/2alpha accumulation and this effect is completely reversed by additional iron ions. This is because quercetin and galangin are able to chelate cellular iron ions that are cofactors of HIF-1/2alpha proline hydroxylase (PHD). These data suggest that quercetin inhibits the ubiquitination of HIF-1/2alpha in normoxia by hindering PHD through chelating iron ions.
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Small Molecular TRAIL Inducer ONC201 Induces Death in Lung Cancer Cells: A Preclinical Study.
Feng, Yuan; Zhou, Jihong; Li, Zhanhua; Jiang, Ying; Zhou, Ying
2016-01-01
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) selectively targets cancer cells. The present preclinical study investigated the anti-cancer efficiency of ONC201, a first-in-class small molecule TRAIL inducer, in lung cancer cells. We showed that ONC201 was cytotoxic and anti-proliferative in both established (A549 and H460 lines) and primary human lung cancer cells. It was yet non-cytotoxic to normal lung epithelial cells. Further, ONC201 induced exogenous apoptosis activation in lung cancer cells, which was evidenced by TRAIL/death receptor-5 (DR5) induction and caspase-8 activation. The caspase-8 inhibitor or TRAIL/DR5 siRNA knockdown alleviated ONC201's cytotoxicity against lung cancer cells. Molecularly, ONC201 in-activated Akt-S6K1 and Erk signalings in lung cancer cells, causing Foxo3a nuclear translocation. For the in vivo studies, intraperitoneal injection of ONC201 at well-tolerated doses significantly inhibited xenografted A549 tumor growth in severe combined immunodeficient (SCID) mice. Further, ONC201 administration induced TRAIL/DR5 expression, yet inactivated Akt-S6K1 and Erk in tumor tissues. These results of the study demonstrates the potent anti-lung cancer activity by ONC201.
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Small Molecular TRAIL Inducer ONC201 Induces Death in Lung Cancer Cells: A Preclinical Study.
Directory of Open Access Journals (Sweden)
Yuan Feng
Full Text Available Tumor necrosis factor (TNF-related apoptosis-inducing ligand (TRAIL selectively targets cancer cells. The present preclinical study investigated the anti-cancer efficiency of ONC201, a first-in-class small molecule TRAIL inducer, in lung cancer cells. We showed that ONC201 was cytotoxic and anti-proliferative in both established (A549 and H460 lines and primary human lung cancer cells. It was yet non-cytotoxic to normal lung epithelial cells. Further, ONC201 induced exogenous apoptosis activation in lung cancer cells, which was evidenced by TRAIL/death receptor-5 (DR5 induction and caspase-8 activation. The caspase-8 inhibitor or TRAIL/DR5 siRNA knockdown alleviated ONC201's cytotoxicity against lung cancer cells. Molecularly, ONC201 in-activated Akt-S6K1 and Erk signalings in lung cancer cells, causing Foxo3a nuclear translocation. For the in vivo studies, intraperitoneal injection of ONC201 at well-tolerated doses significantly inhibited xenografted A549 tumor growth in severe combined immunodeficient (SCID mice. Further, ONC201 administration induced TRAIL/DR5 expression, yet inactivated Akt-S6K1 and Erk in tumor tissues. These results of the study demonstrates the potent anti-lung cancer activity by ONC201.
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Radiation-induced linking reactions in polyethylene
International Nuclear Information System (INIS)
Zoepfl, F.J.
1983-01-01
Three types of measurements are reported relating to chemical reactions in polyethylene induced by ionizing radiation: 1) viscometric and low-angle laser light scattering measurements to determine the effect of a radical scavenger on the yield of links; 2) calorimetric measurements to determine the effect of radiation-induced linking on the melting behavior of polyethylene; and 3) high-resolution solution carbon 13 nuclear magnetic resonance (NMR) spectrometry measurements to determine the nature of the links and the method of their formation. The NMR results present the first direct detection of radiation-induced long-chain branching (Y links) in polyethylene, and place an apparent upper limit on the yield of H-shaped crosslinks that are formed when polyethylene is irradiated to low absorbed doses. The effect of radiation-induced linking on the melting behavior of polyethylene was examined using differential scanning calorimetry (DSC). It was found that radiation-induced links do not change the heat of fusion of polythylene crystals, but decrease the melt entropy and increase the fold surface free energy per unit area of the crystals. The carbon 13 NMR results demonstrate that long-chain branches (Y links) are formed much more frequently than H-shaped crosslinks at low absorbed doses. The Y links are produced by reactions of alkyl free radicals with terminal vinyl groups in polyethylene
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Induced-Fission Imaging of Nuclear Material
International Nuclear Information System (INIS)
Hausladen, Paul; Blackston, Matthew A.; Mullens, James Allen; McConchie, Seth M.; Mihalczo, John T.; Bingham, Philip R.; Ericson, Milton Nance; Fabris, Lorenzo
2010-01-01
This paper presents initial results from development of the induced-fission imaging technique, which can be used for the purpose of measuring or verifying the distribution of fissionable material in an unopened container. The technique is based on stimulating fissions in nuclear material with 14 MeV neutrons from an associated-particle deuterium-tritium (D-T) generator and counting the subsequent induced fast fission neutrons with an array of fast organic scintillation detectors. For each source neutron incident on the container, the neutron creation time and initial trajectory are known from detection of the associated alpha particle of the d + t → α + n reaction. Many induced fissions will lie along (or near) the interrogating neutron path, allowing an image of the spatial distribution of prompt induced fissions, and thereby fissionable material, to be constructed. A variety of induced-fission imaging measurements have been performed at Oak Ridge National Laboratory with a portable, low-dose D-T generator, including single-view radiographic measurements and three-dimensional tomographic measurements. Results from these measurements will be presented along with the neutron transmission images that have been performed simultaneously. This new capability may have applications to a number of areas in which there may be a need to confirm the presence or configuration of nuclear materials, such as nuclear material control and accountability, quality assurance, treaty confirmation, or homeland security applications.
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Nutritional Interventions for Cancer-induced Cachexia
Gullett, Norleena P.; Mazurak, Vera; Hebbar, Gautam; Ziegler, Thomas R.
2011-01-01
Cancer-induced cachexia remains a significant cause of morbidity and mortality in cancer treatment. Cancer research and development continues at an aggressive pace and yet a degree of cancer-induced cachexia is experienced by up to 80% of advanced stage cancer patients. Unfortunately, there are no established treatment regimens for this condition. Weight loss and fatigue consistently appear in patient oncologic histories and progress notes. However, few oncologists fully understand the pathologic mechanisms causing cachexia resulting in well-meaning advice to increase caloric intake with minimal results. Our goal is to describe the pathologic basis of cancer-induced cachexia and to detail accompanying metabolic derangements. Understanding the causes of cachexia sheds light on the subsequent need for multi-modality therapy including clinical intervention with specialized nutrition support, drug therapy, lifestyle and diet changes. In addition to nutrition support modalities, practicing oncologists may prescribe medical therapies designed to increase body weight and lean body mass, including megestrol acetate, tetrahydrocannibinol, oxandrolone, and non-steroidal anti-inflammatory drugs. A variety of experimental therapies are also being investigated for cancer-induced cachexia including tumor necrosis factor-alpha inhibitors and ghrelin infusions. We review the available data to support nutrition-oriented interventions in cancer-induced cachexia, including omega-3 fatty acids, amino-acid loading/protein supplementation, parenteral and enteral nutrition support, and food-derived compounds such as curcumin, reservatrol, and pomegranate. PMID:21420558
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Inducible Clindamycin Resistance in Staphylococcus Species
International Nuclear Information System (INIS)
Afridi, F. I.; Zeb, M.; Farooqi, B. J.; Murtaza, G.; Hussain, A.
2014-01-01
Objective: To determine the frequency of inducible clindamycin resistance in clinical isolates of Staphylococcus species by phenotypic D-test. Study Design: Observational study. Place and Duration of Study: Ziauddin University Hospital, Karachi, from July to December 2011. Methodology: Consecutive clinical isolates of Staphylococcus species were collected and identified by conventional microbiological techniques. Antimicrobial susceptibility testing and inducible clindamycin resistance was carried out by performing D-test using CLSI criteria. Methicillin resistance was detected by using Cefoxitin disk as a surrogate marker. Statistical analysis was performed by SPSS version-17. Results: A total of 667 clinical isolates of Staphylococcus species were obtained during the study period. In these isolates, 177 (26.5%) were Staphylococcus aureus, and 490 (73.5%) were coagulase negative Staphylococci. The total frequency of inducible clindamycin resistance among isolates of Staphylococcus species was 120/667 (18%). Frequency of inducible clindamycin resistance among coagulase negative Staphylococci group and Staphylococcus aureus group were 18.57% and 16.38% respectively. Median age of patients in D-test positive group was 19.5 (1 - 54) years. Conclusion: The frequency of inducible clindamycin resistance among Staphylococcus species may differ in different hospital setup. Clinical microbiology laboratories should implement testing simple and effective D-test on all Staphylococcus species. D-test positive isolates should be reported clindamycin resistant to decrease treatment failure. (author)
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Self-induced free surface oscillations caused by water jet
International Nuclear Information System (INIS)
Fukaya, M.; Madarame, H.; Okamoto, K.; Iida, M.; Someya, S.
1995-01-01
The interaction between the high speed flow and the free surfaces could induced surface oscillations. Recently, some kinds of self-induced free surface oscillations caused by water jet were discovered, e.g., a self-induced sloshing, 'Jet-Flutter' and a self-induced manometer oscillation. These oscillations have many different characteristics with each other. In this study, the similarities and differences of these oscillations are examined, and the geometrical effects on the phenomena are experimentally investigated. The self-induced sloshing and the Jet-Flutter have different dimensionless traveling times, which suggests a difference in the energy supply mechanism. When the distance between the inlet and the outlet is small in a vessel, the self-induced manometer oscillation could occur in the multi-free-surface system. (author)
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Energy Technology Data Exchange (ETDEWEB)
Seidel, Clemens; Kuhnt, Thomas; Kortmann, Rolf-Dieter; Hering, Kathrin [Leipzig University, Department of Radiotherapy and Radiation Oncology, Leipzig (Germany)
2015-10-15
In recent years, camptocormia and dropped head syndrome (DHS) have gained attention as particular forms of movement disorders. Camptocormia presents with involuntary forward flexion of the thoracolumbar spine that typically increases during walking or standing and may severely impede walking ability. DHS is characterized by weakness of the neck extensors and a consecutive inability to extend the neck; in severe cases the head is fixed in a ''chin to chest position.'' Many diseases may underlie these conditions, and there have been some reports about radiation-induced camptocormia and DHS. A PubMed search with the keywords ''camptocormia,'' ''dropped head syndrome,'' ''radiation-induced myopathy,'' ''radiation-induced neuropathy,'' and ''radiation-induced movement disorder'' was carried out to better characterize radiation-induced movement disorders and the radiation techniques involved. In addition, the case of a patient developing camptocormia 23 years after radiation therapy of a non-Hodgkin's lymphoma of the abdomen is described. In total, nine case series of radiation-induced DHS (n = 45 patients) and - including our case - three case reports (n = 3 patients) about radiogenic camptocormia were retrieved. Most cases (40/45 patients) occurred less than 15 years after radiotherapy involving extended fields for Hodgkin's disease. The use of wide radiation fields including many spinal segments with paraspinal muscles may lead to radiation-induced movement disorders. If paraspinal muscles and the thoracolumbar spine are involved, the clinical presentation can be that of camptocormia. DHS may result if there is involvement of the cervical spine. To prevent these disorders, sparing of the spine and paraspinal muscles is desirable. (orig.) [German] In den letzten Jahren haben Bewegungsstoerungen von Wirbelsaeule und paraspinaler Muskulatur in
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DNA damage-inducible transcripts in mammalian cells
International Nuclear Information System (INIS)
Fornace, A.J. Jr.; Alamo, I. Jr.; Hollander, M.C.
1988-01-01
Hybridization subtraction at low ratios of RNA to cDNA was used to enrich for the cDNA of transcripts increased in Chinese hamster cells after UV irradiation. Forty-nine different cDNA clones were isolated. Most coded for nonabundant transcripts rapidly induced 2- to 10-fold after UV irradiation. Only 2 of the 20 cDNA clones sequenced matched known sequences (metallothionein I and II). The predicted amino acid sequence of one cDNA had two localized areas of homology with the rat helix-destabilizing protein. These areas of homology were at the two DNA-binding sites of this nucleic acid single-strand-binding protein. The induced transcripts were separated into two general classes. Class I transcripts were induced by UV radiation and not by the alkylating agent methyl methanesulfonate. Class II transcripts were induced by UV radiation and by methyl methanesulfonate. Many class II transcripts were induced also by H2O2 and various alkylating agents but not by heat shock, phorbol 12-tetradecanoate 13-acetate, or DNA-damaging agents which do not produce high levels of base damage. Since many of the cDNA clones coded for transcripts which were induced rapidly and only by certain types of DNA-damaging agents, their induction is likely a specific response to such damage rather than a general response to cell injury
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Resveratrol induces mitochondrial biogenesis in endothelial cells.
Csiszar, Anna; Labinskyy, Nazar; Pinto, John T; Ballabh, Praveen; Zhang, Hanrui; Losonczy, Gyorgy; Pearson, Kevin; de Cabo, Rafael; Pacher, Pal; Zhang, Cuihua; Ungvari, Zoltan
2009-07-01
Pathways that regulate mitochondrial biogenesis are potential therapeutic targets for the amelioration of endothelial dysfunction and vascular disease. Resveratrol was shown to impact mitochondrial function in skeletal muscle and the liver, but its role in mitochondrial biogenesis in endothelial cells remains poorly defined. The present study determined whether resveratrol induces mitochondrial biogenesis in cultured human coronary arterial endothelial cells (CAECs). In CAECs resveratrol increased mitochondrial mass and mitochondrial DNA content, upregulated protein expression of electron transport chain constituents, and induced mitochondrial biogenesis factors (proliferator-activated receptor-coactivator-1alpha, nuclear respiratory factor-1, mitochondrial transcription factor A). Sirtuin 1 (SIRT1) was induced, and endothelial nitric oxide (NO) synthase (eNOS) was upregulated in a SIRT1-dependent manner. Knockdown of SIRT1 (small interfering RNA) or inhibition of NO synthesis prevented resveratrol-induced mitochondrial biogenesis. In aortas of type 2 diabetic (db/db) mice impaired mitochondrial biogenesis was normalized by chronic resveratrol treatment, showing the in vivo relevance of our findings. Resveratrol increases mitochondrial content in endothelial cells via activating SIRT1. We propose that SIRT1, via a pathway that involves the upregulation of eNOS, induces mitochondrial biogenesis. Resveratrol induced mitochondrial biogenesis in the aortas of type 2 diabetic mice, suggesting the potential for new treatment approaches targeting endothelial mitochondria in metabolic diseases.
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Serotonergic involvement in stress-induced vasopressin and oxytocin secretion
DEFF Research Database (Denmark)
Jørgensen, Henrik; Knigge, Ulrich; Kjaer, Andreas
2002-01-01
OBJECTIVE: To investigate the involvement of serotonin (5-hydroxytryptamine - 5-HT) receptors in mediation of stress-induced arginine vasopressin (AVP) and oxytocin (OT) secretion in male rats. DESIGN: Experiments on laboratory rats with control groups. METHODS: Different stress paradigms were...... the swim stress-induced OT response. CONCLUSION: 5-HT(2A), 5-HT(2C) and possibly 5-HT(3) and 5-HT(4) receptors, but not 5-HT(1A) receptors, are involved in the restraint stress-induced AVP secretion. 5-HT does not seem to be involved in the dehydration- or hemorrhage-induced AVP response. The restraint...... stress-induced OT response seems to be mediated via 5-HT(1A), 5-HT(2A) and 5-HT(2C) receptors. The dehydration and hemorrhage-induced OT responses are at least mediated by the 5-HT(2A) and 5-HT(2C) receptors. The 5-HT(3) and 5-HT(4) receptors are not involved in stress-induced OT secretion....
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Electrically induced muscle cramps induce hypertrophy of calf muscles in healthy adults.
Behringer, M; Moser, M; Montag, J; McCourt, M; Tenner, D; Mester, J
2015-06-01
Skeletal muscles usually cramp at short lengths, where the tension that can be exerted by muscle fibers is low. Since high tension is an important anabolic stimulus, it is questionable if cramps can induce hypertrophy and strength gains. In the present study we investigated if electrically induced cramps (EIMCs) can elicit these adaptations. 15 healthy male adults were randomly assigned to an intervention (IG; n=10) and a control group (CG; n=5). The cramp protocol (CP) applied twice a week to one leg of the IG, consisted of 3x6 EIMCs, of 5 s each. Calf muscles of the opposite leg were stimulated equally, but were hindered from cramping by fixating the ankle at 0° plantar flexion (nCP). After six weeks, the cross sectional area of the triceps surae was similarly increased in both the CP (+9.0±3.4%) and the nCP (+6.8±3.7%). By contrast, force of maximal voluntary contractions, measured at 0° and 30° plantar flexion, increased significantly only in nCP (0°: +8.5±8.8%; 30°: 11.7±13.7%). The present data indicate that muscle cramps can induce hypertrophy in calf muscles, though lacking high tension as an important anabolic stimulus.
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Fluid injection and induced seismicity
Kendall, Michael; Verdon, James
2016-04-01
The link between fluid injection, or extraction, and induced seismicity has been observed in reservoirs for many decades. In fact spatial mapping of low magnitude events is routinely used to estimate a stimulated reservoir volume. However, the link between subsurface fluid injection and larger felt seismicity is less clear and has attracted recent interest with a dramatic increase in earthquakes associated with the disposal of oilfield waste fluids. In a few cases, hydraulic fracturing has also been linked to induced seismicity. Much can be learned from past case-studies of induced seismicity so that we can better understand the risks posed. Here we examine 12 case examples and consider in particular controls on maximum event size, lateral event distributions, and event depths. Our results suggest that injection volume is a better control on maximum magnitude than past, natural seismicity in a region. This might, however, simply reflect the lack of baseline monitoring and/or long-term seismic records in certain regions. To address this in the UK, the British Geological Survey is leading the deployment of monitoring arrays in prospective shale gas areas in Lancashire and Yorkshire. In most cases, seismicity is generally located in close vicinity to the injection site. However, in some cases, the nearest events are up to 5km from the injection point. This gives an indication of the minimum radius of influence of such fluid injection projects. The most distant events are never more than 20km from the injection point, perhaps implying a maximum radius of influence. Some events are located in the target reservoir, but most occur below the injection depth. In fact, most events lie in the crystalline basement underlying the sedimentary rocks. This suggests that induced seismicity may not pose a leakage risk for fluid migration back to the surface, as it does not impact caprock integrity. A useful application for microseismic data is to try and forecast induced seismicity
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Macrophage migration inhibitory factor induces vascular leakage via autophagy
Directory of Open Access Journals (Sweden)
Hong-Ru Chen
2015-01-01
Full Text Available Vascular leakage is an important feature of acute inflammatory shock, which currently has no effective treatment. Macrophage migration inhibitory factor (MIF is a pro-inflammatory cytokine that can induce vascular leakage and plays an important role in the pathogenesis of shock. However, the mechanism of MIF-induced vascular leakage is still unclear. In this study, using recombinant MIF (rMIF, we demonstrated that MIF induced disorganization and degradation of junction proteins and increased the permeability of human endothelial cells in vitro. Western blotting analysis showed that rMIF treatment induced LC3 conversion and p62 degradation. Inhibition of autophagy with a PI3K inhibitor (3-MA, a ROS scavenger (NAC or autophagosomal-lysosomal fusion inhibitors (bafilomycin A1 and chloroquine rescued rMIF-induced vascular leakage, suggesting that autophagy mediates MIF-induced vascular leakage. The potential involvement of other signaling pathways was also studied using different inhibitors, and the results suggested that MIF-induced vascular leakage may occur through the ERK pathway. In conclusion, we showed that MIF triggered autophagic degradation of endothelial cells, resulting in vascular leakage. Inhibition of MIF-induced autophagy may provide therapeutic targets against vascular leakage in inflammatory shock.
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Radiation-induced heart injury
International Nuclear Information System (INIS)
Suzuki, Yoshihiko; Niibe, Hideo
1975-01-01
In order to identify radiation-induced heart injury and to differentiate it from heart disease, an attempt was made to clarify post-irradiation heart injury by investigating the histological changes which occur during the internal between the irradiation and the time of demonstrable histological changes. A study was made of 83 autopsies in which most of the primary neoplasms were breast cancers, lung cancers and mediastinal tumors. In 43 of these autopsies the heart had been irradiated. Sixty eight dd-strain mice were also used for microautoradiographic study. Histological changes in the heart were observed in 27 of the 43 cases receiving irradiation. The limit of the tolerance dose to the heart for indicating histological changes was 1220 ret in humans. The latent period without histological changes was 2.7 months after initiation of radiation therapy. Greater heart injury was observed after re-irradiation or after the combined therapy of radiation and chemotherapy especially mitomycin (MMC). The histological findings after treatment with MMC were similar to those of radiation-induced heart injury. Results of the study indicate that the damage is secondary to radiation-induced changes of the vascula connective tissue. (Evans, G.)
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Energy Technology Data Exchange (ETDEWEB)
Brandt, Bastian B. [Institute for Theoretical Physics, Goethe-University of Frankfurt,60438 Frankfurt (Germany); Institute for Theoretical Physics, University of Regensburg,93040 Regensburg (Germany); Lohmayer, Robert; Wettig, Tilo [Institute for Theoretical Physics, University of Regensburg,93040 Regensburg (Germany)
2016-11-14
We explore an alternative discretization of continuum SU(N{sub c}) Yang-Mills theory on a Euclidean spacetime lattice, originally introduced by Budzcies and Zirnbauer. In this discretization the self-interactions of the gauge field are induced by a path integral over N{sub b} auxiliary boson fields, which are coupled linearly to the gauge field. The main progress compared to earlier approaches is that N{sub b} can be as small as N{sub c}. In the present paper we (i) extend the proof that the continuum limit of the new discretization reproduces Yang-Mills theory in two dimensions from gauge group U(N{sub c}) to SU(N{sub c}), (ii) derive refined bounds on N{sub b} for non-integer values, and (iii) perform a perturbative calculation to match the bare parameter of the induced gauge theory to the standard lattice coupling. In follow-up papers we will present numerical evidence in support of the conjecture that the induced gauge theory reproduces Yang-Mills theory also in three and four dimensions, and explore the possibility to integrate out the gauge fields to arrive at a dual formulation of lattice QCD.
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[Drug-induced oral ulcerations].
Madinier, I; Berry, N; Chichmanian, R M
2000-06-01
Different side effects of drugs have been described in the oral cavity, including oral ulcerations. Direct contact between drugs and oral mucosa may induce chemical burn or local hypersensitivity. Less frequently, these drug-induced oral ulcerations are part of a complex reaction with cutaneous or systemic manifestations. Sometimes, one or more oral ulcerations appear as the main side-effect of a drug, or exceptionally as solitary lesions. Solitary oral ulcerations usually appear after few weeks of treatment. In most of cases, these lesions resist to conventional treatments, with a rapid healing following the suppression of the responsible drug. This diagnosis is usually difficult, particularly with patients receiving multiple drug therapy. Besides, special attention must be paid to new drugs. Oral ulcerations following symptoms of burning mouth, metallic taste, dysgueusia or agueusia are strongly suggestive of a pharmacological origin. Most of the molecules able to induce solitary oral ulcerations are commonly prescribed in a) rheumatology: NSAI (diclofenac, flurbiprofen, indomethacin, naproxen), long-term rheumatoid arthritis therapy (azathioprine, methotrexate, penicillamine, gold compounds, tiopronin); b) cardiology: angiotensin-converting-enzyme inhibitors (captopril, enalapril), angiotensin 2-receptor antagonist (losartan), anti-angorous (nicorandil), c) psychiatry: antidepressants (fluoxetine, lithium), d) AIDS therapy (foscarnet, zalcitabine).
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Martin, D S; Desser, S S; Hong, H
1992-04-01
Six metabolic enzymes, glucose-6-phosphate dehydrogenase, glucosephosphate isomerase, isocitrate dehydrogenase, malate dehydrogenase, phosphoglucomutase, and purine nucleoside phosphorylase, from clonal isolates of 3 presumptive species of Trypanosoma (T. fallisi, T. ranarum, and T. rotatorium) from 3 anuran hosts (Bufo americanus, Rana clamitans, and Rana catesbeiana) were compared using starch-gel electrophoresis. Although bands were shared among the different zymodemes of isolates of the same host genus, low genetic polymorphism of the enzyme loci was observed with few apparent shared bands between samples isolated from frogs and toads. A distance value calculated between toad and frog trypanosome isolates suggests the likelihood of long-time separation of species. Cluster analysis based on overall similarity distinguished the trypanosomes of toads and frogs as separate taxa, suggesting that host specificity and observed morphological differences are consistent with heritable allozyme differences.
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Directory of Open Access Journals (Sweden)
Shawna T. Park
2014-01-01
Full Text Available 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.
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Perceptual, not memorial, disruption underlies emotion-induced blindness.
Kennedy, Briana L; Most, Steven B
2012-04-01
Emotion-induced blindness refers to impaired awareness of stimuli appearing in the temporal wake of an emotionally arousing stimulus (S. B. Most, Chun, Widders, & Zald, 2005). In previous emotion-induced blindness experiments, participants withheld target responses until the end of a rapid stream of stimuli, even though each target appeared in the middle of the stream. The resulting interval between the targets' offset and participants' initiation of a response leaves open the possibility that emotion-induced blindness reflects a failure to encode or maintain target information in memory rather than a failure of perception. In the present study, participants engaged in a typical emotion-induced blindness task but initiated a response immediately upon seeing each target. Emotion-induced blindness was nevertheless robust. This suggests that emotion-induced blindness is not attributable to the delay between awareness of a target and the initiation of a response, but rather reflects the disruptive impact of emotional distractors on mechanisms driving conscious perception. (PsycINFO Database Record (c) 2012 APA, all rights reserved).
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Femtosecond laser-induced herringbone patterns
Garcell, Erik M.; Lam, Billy; Guo, Chunlei
2018-06-01
Femtosecond laser-induced herringbone patterns are formed on copper (Cu). These novel periodic structures are created following s-polarized, large incident angle, femtosecond laser pulses. Forming as slanted and axially symmetric laser-induced periodic surface structures along the side walls of ablated channels, the result is a series of v-shaped structures that resemble a herringbone pattern. Fluence mapping, incident angle studies, as well as polarization studies have been conducted and provide a clear understanding of this new structure.
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Radiation-induced attenuation in integrated optical materials
International Nuclear Information System (INIS)
Evans, B.D.
1989-01-01
This paper reports that three materials commonly employed in opto-electronic integrated circuits evaluated for radiation-induced optical attenuation in the range 300 nm to 3000 nm. These include optically clear epoxy and crystalline lithium niobate after Co-60 exposure and crystalline tellurium dioxide after mixed gamma/fast-neutron exposure. In all these materials, however, induced loss was restricted to shorter wavelengths; attenuation induced at the telecommunications windows near 850, 1300 and 1550 nm was <0.1 dB/cm
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Glucocorticoid Induced Leucine Zipper inhibits apoptosis of cardiomyocytes by doxorubicin
International Nuclear Information System (INIS)
Aguilar, David; Strom, Joshua; Chen, Qin M.
2014-01-01
Doxorubicin (Dox) is an indispensable chemotherapeutic agent for the treatment of various forms of neoplasia such as lung, breast, ovarian, and bladder cancers. Cardiotoxicity is a major concern for patients receiving Dox therapy. Previous work from our laboratory indicated that glucocorticoids (GCs) alleviate Dox-induced apoptosis in cardiomyocytes. Here we have found Glucocorticoid-Induced Leucine Zipper (GILZ) to be a mediator of GC-induced cytoprotection. GILZ was found to be induced in cardiomyocytes by GC treatment. Knocking down of GILZ using siRNA resulted in cancelation of GC-induced cytoprotection against apoptosis by Dox treatment. Overexpressing GILZ by transfection was able to protect cells from apoptosis induced by Dox as measured by caspase activation, Annexin V binding and morphologic changes. Western blot analyses indicate that GILZ overexpression prevented cytochrome c release from mitochondria and cleavage of caspase-3. When bcl-2 family proteins were examined, we found that GILZ overexpression causes induction of the pro-survival protein Bcl-xL. Since siRNA against Bcl-xL reverses GC induced cytoprotection, Bcl-xL induction represents an important event in GILZ-induced cytoprotection. Our data suggest that GILZ functions as a cytoprotective gene in cardiomyocytes. - Highlights: • Corticosteroids act as a cytoprotective agent in cardiomyocytes • Corticosteroids induce GILZ expression in cardiomyocytes • Elevated GILZ results in resistance against apoptosis induced by doxorubicin • GILZ induces Bcl-xL protein without inducing Bcl-xL mRNA
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DEFF Research Database (Denmark)
Arngrim, Nanna; Schytz, Henrik Winther; Britze, Josefine
2016-01-01
in the visual cortex were measured by proton magnetic resonance spectroscopy. The circumference of cranial arteries was measured by 3 T high-resolution magnetic resonance angiography. Hypoxia induced migraine-like attacks in eight patients compared to one patient after sham (P = 0.039), aura in three...... and possible aura in 4 of 15 patients. Hypoxia did not change glutamate concentration in the visual cortex compared to sham, but increased lactate concentration (P = 0.028) and circumference of the cranial arteries (P ... suggests that hypoxia may provoke migraine headache and aura symptoms in some patients. The mechanisms behind the migraine-inducing effect of hypoxia should be further investigated....
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Cervical osteophyte induced dysphagia
International Nuclear Information System (INIS)
Davies, R.P.; Sage, M.R.; Brophy, B.P.
1989-01-01
Although cervical spondylosis is a common disorder, dysphagia induced by osteophyte formation is uncommon. Fewer than one hundred cases of cervical osteophyte induced dysphagia have been reported, with little attention to the diagnosis by barium swallow. The radiological features of two cases treated surgically with good results are described. Both cases complained of dysphagia while one had associated respiratory obstruction on forward flexion of his neck. The features on barium study of cervical osteophytes causing dysphagia include deformity at the level of osteophyte formation, in both AP and lateral projections. Tracheal aspirations due to deformity at the laryngeal inlet and interference with epiglottic retroversion may be present. 8 refs., 3 figs
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National Research Council Canada - National Science Library
Maidanik, G
2002-01-01
The induced noise control parameter is defined in terms of the ratio of the stored energy in a master dynamic system, when it is coupled to an adjunct dynamic system, to that stored energy when the coupling is absent...
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Radiation-induced brain injury: A review
Directory of Open Access Journals (Sweden)
Michael eRobbins
2012-07-01
Full Text Available Approximately 100,000 primary and metastatic brain tumor patients/year in the US survive long enough (> 6 months to experience radiation-induced brain injury. Prior to 1970, the human brain was thought to be highly radioresistant; the acute CNS syndrome occurs after single doses > 30 Gy; white matter necrosis occurs at fractionated doses > 60 Gy. Although white matter necrosis is uncommon with modern techniques, functional deficits, including progressive impairments in memory, attention, and executive function have become important, because they have profound effects on quality of life. Preclinical studies have provided valuable insights into the pathogenesis of radiation-induced cognitive impairment. Given its central role in memory and neurogenesis, the majority of these studies have focused on the hippocampus. Irradiating pediatric and young adult rodent brains leads to several hippocampal changes including neuroinflammation and a marked reduction in neurogenesis. These data have been interpreted to suggest that shielding the hippocampus will prevent clinical radiation-induced cognitive impairment. However, this interpretation may be overly simplistic. Studies using older rodents, that more closely match the adult human brain tumor population, indicate that, unlike pediatric and young adult rats, older rats fail to show a radiation-induced decrease in neurogenesis or a loss of mature neurons. Nevertheless, older rats still exhibit cognitive impairment. This occurs in the absence of demyelination and/or white matter necrosis similar to what is observed clinically, suggesting that more subtle molecular, cellular and/or microanatomic modifications are involved in this radiation-induced brain injury. Given that radiation-induced cognitive impairment likely reflects damage to both hippocampal- and non-hippocampal-dependent domains, there is a critical need to investigate the microanatomic and functional effects of radiation in various brain
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Proton induced X-ray emission analysis
International Nuclear Information System (INIS)
Khan, Rashiduzzman
1976-09-01
The developments in proton induced X-ray emission analysis are reviewed. Techniques for analyzing thick and thin samples of different origin are described. Discussions on the application of proton induced X-ray emission analysis in different fields, comparison of the sensitivity of this method with other analytical techniques, its limitations and possible improvements are presented
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Rand, Lucinda; Hinds, Jason; Springer, Burkhard; Sander, Peter; Buxton, Roger S; Davis, Elaine O
2003-11-01
In many species of bacteria most inducible DNA repair genes are regulated by LexA homologues and are dependent on RecA for induction. We have shown previously by analysing the induction of recA that two mechanisms for the induction of gene expression following DNA damage exist in Mycobacterium tuberculosis. Whereas one of these depends on RecA and LexA in the classical way, the other mechanism is independent of both of these proteins and induction occurs in the absence of RecA. Here we investigate the generality of each of these mechanisms by analysing the global response to DNA damage in both wild-type M. tuberculosis and a recA deletion strain of M. tuberculosis using microarrays. This revealed that the majority of the genes that were induced remained inducible in the recA mutant stain. Of particular note most of the inducible genes with known or predicted functions in DNA repair did not depend on recA for induction. Amongst these are genes involved in nucleotide excision repair, base excision repair, damage reversal and recombination. Thus, it appears that this novel mechanism of gene regulation is important for DNA repair in M. tuberculosis.
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Muthuramu, Ilayaraja; Amin, Ruhul; Postnov, Andrey; Mishra, Mudit; Jacobs, Frank; Gheysens, Olivier; Van Veldhoven, Paul P; De Geest, Bart
2017-07-18
Studies evaluating the effects of high-saturated fat diets on cardiac function are most often confounded by diet-induced obesity and by systemic insulin resistance. We evaluated whether coconut oil, containing C12:0 and C14:0 as main fatty acids, aggravates pressure overload-induced cardiomyopathy induced by transverse aortic constriction (TAC) in C57BL/6 mice. Mortality rate after TAC was higher ( p coconut oil diet-fed mice than in standard chow-fed mice (hazard ratio 2.32, 95% confidence interval 1.16 to 4.64) during eight weeks of follow-up. The effects of coconut oil on cardiac remodeling occurred in the absence of weight gain and of systemic insulin resistance. Wet lung weight was 1.76-fold ( p coconut oil mice than in standard chow mice. Myocardial capillary density ( p coconut oil mice than in standard chow mice. Myocardial glucose uptake was 1.86-fold ( p coconut oil mice and was accompanied by higher myocardial pyruvate dehydrogenase levels and higher acetyl-CoA carboxylase levels. The coconut oil diet increased oxidative stress. Myocardial triglycerides and free fatty acids were lower ( p coconut oil mice. In conclusion, coconut oil aggravates pressure overload-induced cardiomyopathy.
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Directory of Open Access Journals (Sweden)
Dahle Jostein
2005-01-01
Full Text Available Abstract Background Genomic instability is characteristic of many types of human cancer. Recently, we reported that ultraviolet radiation induced elevated mutation rates and chromosomal instability for many cell generations after ultraviolet irradiation. The increased mutation rates of unstable cells may allow them to accumulate aberrations that subsequently lead to cancer. Ultraviolet A radiation, which primarily acts by oxidative stress, and ultraviolet B radiation, which initially acts by absorption in DNA and direct damage to DNA, both produced genomically unstable cell clones. In this study, we have determined the effect of antioxidants on induction of delayed mutations by ultraviolet radiation. Delayed mutations are indicative of genomic instability. Methods Delayed mutations in the hypoxanthine phosphoribosyl transferase (hprt gene were detected by incubating the cells in medium selectively killing hprt mutants for 8 days after irradiation, followed by a 5 day period in normal medium before determining mutation frequencies. Results The UVB-induced delayed hprt mutations were strongly inhibited by the antioxidants catalase, reduced glutathione and superoxide dismutase, while only reduced glutathione had a significant effect on UVA-induced delayed mutations. Treatment with antioxidants had only minor effects on early mutation frequenies, except that reduced glutathione decreased the UVB-induced early mutation frequency by 24 %. Incubation with reduced glutathione was shown to significantly increase the intracellular amount of reduced glutathione. Conclusion The strong effects of these antioxidants indicate that genomic instability, which is induced by the fundamentally different ultraviolet A and ultraviolet B radiation, is mediated by reactive oxygen species, including hydrogen peroxide and downstream products. However, cells take up neither catalase nor SOD, while incubation with glutathione resulted in increased intracellular levels of
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CEREBRAL CORTEX DAMAGE INDUCED BY ACUTE ORAL ...
African Journals Online (AJOL)
2018-02-28
Feb 28, 2018 ... This study examines alcohol-induced cerebral cortex damage and the association with oxidative ... alcohol has profound effects on the function ... Chronic use of ..... Alcohol induced brain damage and liver damage in young.
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Magnetomechanically induced long period fiber gratings
International Nuclear Information System (INIS)
Causado-Buelvas, Jesus D.; Gomez-Cardona, Nelson D.; Torres, Pedro
2008-01-01
In this work, we report a simple, flexible method to create long period fiber gratings mechanically by controlling the repulsion/attraction force between two magnets that pressing a plate with a periodic array of small glass cylinders to a short length of optical fiber. Via the photoelastic effect, the pressure points induce the required periodic refractive index modulation to create the LPFG. We found that the induced device exhibits spectral characteristics similar to those of other types of LPFG. As the optical properties of LPFGs are directly related to the nature of the applied perturbations, we show, to our knowledge for the frrst time, how is the evolution of birefringence effects in mechanically induced LPFGs
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Impurity-induced states in superconducting heterostructures
Liu, Dong E.; Rossi, Enrico; Lutchyn, Roman M.
2018-04-01
Heterostructures allow the realization of electronic states that are difficult to obtain in isolated uniform systems. Exemplary is the case of quasi-one-dimensional heterostructures formed by a superconductor and a semiconductor with spin-orbit coupling in which Majorana zero-energy modes can be realized. We study the effect of a single impurity on the energy spectrum of superconducting heterostructures. We find that the coupling between the superconductor and the semiconductor can strongly affect the impurity-induced states and may induce additional subgap bound states that are not present in isolated uniform superconductors. For the case of quasi-one-dimensional superconductor/semiconductor heterostructures we obtain the conditions for which the low-energy impurity-induced bound states appear.
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Induced Compton-scattering effects in radiation-transport approximations
International Nuclear Information System (INIS)
Gibson, D.R. Jr.
1982-02-01
The method of characteristics is used to solve radiation transport problems with induced Compton scattering effects included. The methods used to date have only addressed problems in which either induced Compton scattering is ignored, or problems in which linear scattering is ignored. Also, problems which include both induced Compton scattering and spatial effects have not been considered previously. The introduction of induced scattering into the radiation transport equation results in a quadratic nonlinearity. Methods are developed to solve problems in which both linear and nonlinear Compton scattering are important. Solutions to scattering problems are found for a variety of initial photon energy distributions
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Inducement of radionuclides targeting therapy by gene transfection
International Nuclear Information System (INIS)
Luo Quanyong
2001-01-01
The author presents an overview of gene transfection methods to genetically induce tumor cells to express enhanced levels of cell surface antigens and receptors to intake radiolabeled antibody and peptide targeting and thus increase their therapeutic effect in radiotherapy. The current research include inducement of radioimmunotherapy through CEA gene transfection, inducement of iodine-131 therapy by sodium iodide symporter gene transfection and inducement of MIBG therapy by noradrenaline transporter gene transfection. These studies raise the prospect that gene-therapy techniques could be used to enable the treatment of a wide range of tumors with radiopharmaceuticals of established clinical acceptability
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Glucocorticoid-induced hyperglycaemia
Gerards, M.C.
2018-01-01
This thesis contains studies on current practice, clinical implications and treatment of excess glucocorticoid receptor (GCR) stimulation, with a focus on glucocorticoid-induced hyperglycaemia (GCIH). Chapter 1 is a general introduction to the glucocorticoid hormone. In chapter 2 , we have
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Advertising-Induced Embarrassment
Puntoni, S.; Hooge, de I.E.; Verbeke, W.J.M.I.
2015-01-01
Abstract Consumer embarrassment is a concern for many advertisers. Yet little is known about ad-induced embarrassment. The authors investigate when and why consumers experience embarrassment as a result of exposure to socially sensitive advertisements. The theory distinguishes between viewing
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Exorcising ghosts in induced gravity
Energy Technology Data Exchange (ETDEWEB)
Narain, Gaurav [Chinese Academy of Sciences (CAS), Key Laboratory of Theoretical Physics, Kavli Institute for Theoretical Physics China (KITPC), Institute of Theoretical Physics, Beijing (China)
2017-10-15
Unitarity of the scale-invariant coupled theory of higher-derivative gravity and matter is investigated. A scalar field coupled with a Dirac fermion is taken as the matter sector. Following the idea of induced gravity the Einstein-Hilbert term is generated via dynamical symmetry breaking of scale invariance. The renormalisation group flows are computed and one-loop RG improved effective potential of scalar is calculated. The scalar field develops a new minimum via the Coleman-Weinberg procedure inducing the Newton constant and masses in the matter sector. The spin-2 problematic ghost and the spin-0 mode of the metric fluctuation get a mass in the broken phase of the theory. The energy dependence of the vacuum expectation value in the RG improved scenario implies a running for the induced parameters. This sets up platform to ask whether it is possible to evade the spin-2 ghost by keeping its mass always above the running energy scale? In broken phase this question is satisfactorily answered for a large domain of coupling parameter space where the ghost is evaded. The spin-0 mode can be made physically realisable or not depending upon the choice of the initial parameters. The induced Newton constant is seen to vanish in the ultraviolet case. By properly choosing parameters it is possible to make the matter fields physically unrealisable. (orig.)
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Resonant neutron-induced atomic displacements
Energy Technology Data Exchange (ETDEWEB)
Elmaghraby, Elsayed K., E-mail: e.m.k.elmaghraby@gmail.com
2017-05-01
Highlights: • Neutron induced atomic displacements was investigated based on scattering of energy of neutron. • Model for cascade function (multiplication of displacements with increasing energy transfer) was proposed and justified. • Parameterizations for the dpa induced in all elements were performed. • Table containing all necessary parameters to calculate the displacement density induced by neutron is given. • Contribution of non resonance displacement and resonant-neutron induced displacements are distinguished. - Abstract: A model for displacement cascade function was modified to account for the continuous variation of displacement density in the material in response to neutron exposure. The model is based on the Gaussian distribution of displacement energies of atoms in a material. Analytical treatment for moderated epithermal neutron field was given in which the displacement density was divided into two terms, discrete-resonance term and continuum term. Calculation are done for all isotopes using ENDF/B VII.1 data files and temperature dependent cross section library. Weighted elemental values were reported a fitting was performed to obtain energy-dependent formula of displacement density and reduce the number of parameters. Results relevant the present specification of the cascade function are tabulated for each element to enable calculation of displacement density at any value of displacement energy in the between 5 eV and 55 eV.
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Study of UV-induced mutagenesis in Bacillus subtilis
International Nuclear Information System (INIS)
Filippov, V.D.; Lotareva, O.V.
1978-01-01
The mechanism of UV-induced mutagenesis was studied in Bacillus subtilis departing from the assumption that a lower yield of UV-induced mutations should be found in mutants deficient in the recombination if production of mutations is coupled with the recombination process. Three recombination-deficient strains were used: two (recA and recF) with defects in different recombination pathways and the third (recB) has a block at a stage common for both of them. UV light induced reversions to prototrophy in recB cells and did not in recA and recF strains. Direct mutations, which confer to the cell additional growth requirements, were induced by UV light in recA and recF mutants. It is concluded that UV-induced mutagenesis in B subtilis is independent of the two known recombination mechanisms
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Ketamine-induced apoptosis in cultured rat cortical neurons
International Nuclear Information System (INIS)
Takadera, Tsuneo; Ishida, Akira; Ohyashiki, Takao
2006-01-01
Recent data suggest that anesthetic drugs cause neurodegeneration during development. Ketamine is frequently used in infants and toddlers for elective surgeries. The purpose of this study is to determine whether glycogen synthase kinase-3 (GSK-3) is involved in ketamine-induced apoptosis. Ketamine increased apoptotic cell death with morphological changes which were characterized by cell shrinkage, nuclear condensation or fragmentation. In addition, insulin growth factor-1 completely blocked the ketamine-induced apoptotic cell death. Ketamine decreased Akt phosphorylation. GSK-3 is known as a downstream target of Akt. The selective inhibitors of GSK-3 prevented the ketamine-induced apoptosis. Moreover, caspase-3 activation was accompanied by the ketamine-induced cell death and inhibited by the GSK-3 inhibitors. These results suggest that activation of GSK-3 is involved in ketamine-induced apoptosis in rat cortical neurons
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Clinical importance of voluntary and induced Bennett movement.
Tupac, R G
1978-07-01
A total of 136 dentulous patients were divided into three groups for purposes of quantitative pantographic comparison of voluntary and induced Bennett movement. The effects of patient age and operator experience on recording the Bennett movement were also studied. The results indicates that for patients studied with Bennett movement iduced in the manner described: 1. Experienced operators can obtain more induced Bennett movement that inexperienced operators. 2. Inducing Bennett movement has a greater effect on the immediate side shift component than it has on the progressive side shift component. 3. For older individuals the amount and direction of induced immediate side shift is greater than for younger patients, statistically highly significant, and therefore clinically important. In conclusion, if the objective of a pantographic survey is to record the complete capacity of the joint to move, *lateral jaw movements must be induced.
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Lorimore, S A; Wright, E G
2003-01-01
To review studies of radiation responses in the haemopoietic system in the context of radiation-induced genomic instability, bystander effects and inflammatory-type processes. There is considerable evidence that cells that themselves are not exposed to ionizing radiation but are the progeny of cells irradiated many cell divisions previously may express a high frequency of gene mutations, chromosomal aberrations and cell death. These effects are collectively known as radiation-induced genomic instability. A second untargeted effect results in non-irradiated cells exhibiting responses typically associated with direct radiation exposure but occurs as a consequence of contact with irradiated cells or by receiving soluble signals from irradiated cells. These effects are collectively known as radiation-induced bystander effects. Reported effects include increases or decreases in damage-inducible and stress-related proteins; increases or decreases in reactive oxygen species, cell death or cell proliferation, and induction of mutations and chromosome aberrations. This array of responses is reminiscent of effects mediated by cytokines and other similar regulatory factors that may involve, but do not necessarily require, gap junction-mediated transfer, have multiple inducers and a variety of context-dependent consequences in different cell systems. That chromosomal instability in haemopoietic cells can be induced by an indirect bystander-type mechanism both in vitro and in vivo provides a potential link between these two untargeted effects and there are radiation responses in vivo consistent with the microenvironment contributing secondary cell damage as a consequence of an inflammatory-type response to radiation-induced injury. Intercellular signalling, production of cytokines and free radicals are features of inflammatory responses that have the potential for both bystander-mediated and persisting damage as well as for conferring a predisposition to malignancy. The
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Induced surface stress at crystal surfaces
International Nuclear Information System (INIS)
Dahmen, K.
2002-05-01
Changes of the surfaces stress Δτ (s) can be studied by observing the bending of thin crystalline plates. With this cantilever method one can gain the induced change of surface stress Δτ (s) from the bending of plates with the help of elasticity theory. For elastic isotropic substrates the relevant relations are known. Here the relations are generalized to elastic anisotropic crystals with a C 2v - Symmetry. The equilibrium shapes of crystalline plates oriented along the (100)-, (110)-, or (111)-direction which are clamped along one edge are calculated with a numeric method under the load of a homogeneous but pure isotropic or anisotropic surface stress. The results can be displayed with the dimensionality, so that the effect of clamping can be described in a systematic way. With these tabulated values one can evaluate cantilever experiments exactly. These results are generalized to cantilever methods for determining magnetoelastic constants. It is shown which magnetoelastic constants are measured in domains of thin films with ordered structures. The eigenshape and the eigenfrequency of plates constraint through a clamping at one side are calculated. These results give a deeper understanding of the elastic anisotropy. The induced surface stress of oxygen on the (110)-surface of molybdenum is measured along the principle directions Δτ [001] and Δτ [ anti 110] . The anisotropy of the surface stress is found for the p(2 x 2)-reconstruction. Lithium induces a tensile surface stress on the Molybdenum (110)-surface up to a coverage of Θ = 0, 3 monolayer. For a higher coverage the induced stress drops and reaches a level of less than -1, 2 N/m at one monolayer. It is shown, that cobalt induces a linear increasing stress with respect to the coverage on the (100)-surface of copper with a value of 2, 4GPa. The copper (100)-surface is bombarded with accelerated ions in the range between 800-2200 eV. The resulting induced compressive stress (Δτ (s) < 0) of the order
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Tamoxifen induces regression of estradiol-induced mammary cancer in ACI.COP-Ept2 rat model
Ruhlen, Rachel L.; Willbrand, Dana M.; Besch-Williford, Cynthia L.; Ma, Lixin; Shull, James D.; Sauter, Edward R.
2008-01-01
The ACI rat is a unique model of human breast cancer in that mammary cancers are induced by estrogen without carcinogens, irradiation, xenografts or transgenic manipulations. We sought to characterize mammary cancers in a congenic variant of the ACI rat, the ACI.COP-Ept2. All rats with estradiol implants developed mammary cancers in 5–7 months. Rats bearing estradiol-induced mammary cancers were treated with tamoxifen for three weeks. Tamoxifen reduced tumor mass, measured by magnetic resonan...
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Directory of Open Access Journals (Sweden)
Mao-Te Chuang
2011-01-01
Full Text Available 5,16-dihydrotanshinone I (DHTS is extracted from Salvia miltiorrhiza Bunge (tanshen root and was found to be the most effective compound of tanshen extracts against breast cancer cells in our previous studies. However, whether DHTS can induce apoptosis through an endoplasmic reticular (ER stress pathway was examined herein. In this study, we found that DHTS significantly inhibited the proliferation of human prostate DU145 carcinoma cells and induced apoptosis. DHTS was able to induce ER stress as evidenced by the upregulation of glucose regulation protein 78 (GRP78/Bip and CAAT/enhancer binding protein homologous protein/growth arrest- and DNA damage-inducible gene 153 (CHOP/GADD153, as well as increases in phosphorylated eukaryotic initiation factor 2α (eIF2α, c-jun N-terminal kinase (JNK, and X-box-binding protein 1 (XBP1 mRNA splicing forms. DHTS treatment also caused significant accumulation of polyubiquitinated proteins and hypoxia-inducible factor (HIF-1α, indicating that DHTS might be a proteasome inhibitor that is known to induce ER stress or enhance apoptosis caused by the classic ER stress-dependent mechanism. Moreover, DHTS-induced apoptosis was reversed by salubrinal, an ER stress inhibitor. Results suggest that DHTS can induce apoptosis of prostate carcinoma cells via induction of ER stress and/or inhibition of proteasome activity, and may have therapeutic potential for prostate cancer patients.
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Li, Ying; Shi, Bo; Huang, Liping; Wang, Xin; Yu, Xiaona; Guo, Baosheng; Ren, Weidong
2016-12-01
Hypoxia-inducible factor-1α (HIF-1α) has been implicated in the pathogenesis of hypoxic pulmonary hypertension (PH). However, the potential clinical value of HIF-1α as a therapeutic target in the treatment of PH has not yet been evaluated. In this study, an animal model of hypoxia-induced PH was established by exposing adult rats to 10% O2 for 3 weeks, and the effects of the lentivirus-mediated delivery of HIF-1α short hairpin RNA (shRNA) by intratracheal instillation prior to exposure to hypoxia on the manifestations of hypoxia-induced PH were assessed. The successful delivery of HIF-1α shRNA into the pulmonary arteries effectively suppressed the hypoxia-induced upregulation of HIF-1α, accompanied by the prominent attenuation the symptoms associated with hypoxia-induced PH, including the elevation of pulmonary arterial pressure, hypertrophy and hyperplasia of pulmonary artery smooth muscle cells (PASMCs), as well as the muscularization of pulmonary arterioles. In addition, the knockdown of HIF-1α in cultured rat primary PASMCs significantly inhibited the hypoxia-induced acceleration of the cell cycle and the proliferation of the PASMCs, suggesting that HIF-1α may be a direct mediator of PASMC hyperplasia in hypoxia-induced PH. In conclusion, this study demonstrates the potent suppressive effects of HIF-1α shRNA on hypoxia-induced PH and PASMC hyperplasia, providing evidence for the potential application of HIF-1α shRNA in the treatment of hypoxic PH.
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Directory of Open Access Journals (Sweden)
Ahmed Alhusban
2017-01-01
Full Text Available Diabetes mellitus (DM is a major risk factor for cardiovascular disease. Additionally, it was found to induce a dysfunctional angiogenic response in the brain that was attributed to oxidative stress. Milk thistle seed extract (silymarin has potent antioxidant properties, though its potential use in ameliorating diabetes-induced aberrant brain angiogenesis is unknown. Glycogen synthase kinase-3β is a regulator of angiogenesis that is upregulated by diabetes. Its involvement in diabetes-induced angiogenesis is unknown. To evaluate the potential of silymarin to ameliorate diabetes-induced aberrant angiogenesis, human brain endothelial cells (HBEC-5i were treated with 50 μg/mL advanced glycation end (AGE products in the presence or absence of silymarin (50, 100 μM. The angiogenic potential of HBEC-5i was evaluated in terms of migration and in vitro tube formation capacities. The involvement of GSK-3β was also evaluated. AGE significantly increased the migration and tube formation rates of HBEC-5i by about onefold (p=0.0001. Silymarin reduced AGE-induced migration in a dose-dependent manner where 50 μM reduced migration by about 50%, whereas the 100 μM completely inhibited AGE-induced migration. Similarly, silymarin 50 μg/mL blunted AGE-induced tube formation (p=0.001. This effect was mediated through a GSK-3β-dependent inhibition of VEGF release. In conclusion, silymarin inhibits AGE-induced aberrant angiogenesis in a GSK-3β-mediated inhibition of VEGF release.
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Lens, S. M.; den Drijver, B. F.; Pötgens, A. J.; Tesselaar, K.; van Oers, M. H.; van Lier, R. A.
1998-01-01
To dissect intracellular pathways involved in B cell Ag receptor (BCR)-mediated and Fas-induced human B cell death, we isolated clones of the Burkitt lymphoma cell line Ramos with different apoptosis sensitivities. Selection for sensitivity to Fas-induced apoptosis also selected for clones with
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related apoptosis-inducing ligand in transplastomic tobacco
African Journals Online (AJOL)
-inducing ligand (sTRAIL) can, as the whole length TRAIL protein, bind with its receptors and specifically induce the apoptosis of cancer cells; therefore, it has been developed as a potential therapeutic agent for various cancer treatments.
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Lancaster, Graeme I; Febbraio, Mark A
2005-01-01
The heat shock proteins are a family of highly conserved proteins with critical roles in maintaining cellular homeostasis and in protecting the cell from stressful conditions. While the critical intracellular roles of heat shock proteins are undisputed, evidence suggests that the cell possess the necessary machinery to actively secrete specific heat shock proteins in response to cellular stress. In this review, we firstly discuss the evidence that physical exercise induces the release of heat shock protein 72 from specific tissues in humans. Importantly, it appears as though this release is the result of an active secretory process, as opposed to non-specific processes such as cell lysis. Next we discuss recent in vitro evidence that has identified a mechanistic basis for the observation that cellular stress induces the release of a specific subset of heat shock proteins. Importantly, while the classical protein secretory pathway does not seem to be involved in the stress-induced release of HSP72, we discuss the evidence that lipid-rafts and exosomes are important mediators of the stress-induced release of HSP72.
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Mitochondrial dysfunction in lyssavirus-induced apoptosis.
Gholami, Alireza; Kassis, Raïd; Real, Eléonore; Delmas, Olivier; Guadagnini, Stéphanie; Larrous, Florence; Obach, Dorothée; Prevost, Marie-Christine; Jacob, Yves; Bourhy, Hervé
2008-05-01
Lyssaviruses are highly neurotropic viruses associated with neuronal apoptosis. Previous observations have indicated that the matrix proteins (M) of some lyssaviruses induce strong neuronal apoptosis. However, the molecular mechanism(s) involved in this phenomenon is still unknown. We show that for Mokola virus (MOK), a lyssavirus of low pathogenicity, the M (M-MOK) targets mitochondria, disrupts the mitochondrial morphology, and induces apoptosis. Our analysis of truncated M-MOK mutants suggests that the information required for efficient mitochondrial targeting and dysfunction, as well as caspase-9 activation and apoptosis, is held between residues 46 and 110 of M-MOK. We used a yeast two-hybrid approach, a coimmunoprecipitation assay, and confocal microscopy to demonstrate that M-MOK physically associates with the subunit I of the cytochrome c (cyt-c) oxidase (CcO) of the mitochondrial respiratory chain; this is in contrast to the M of the highly pathogenic Thailand lyssavirus (M-THA). M-MOK expression induces a significant decrease in CcO activity, which is not the case with M-THA. M-MOK mutations (K77R and N81E) resulting in a similar sequence to M-THA at positions 77 and 81 annul cyt-c release and apoptosis and restore CcO activity. As expected, the reverse mutations, R77K and E81N, introduced in M-THA induce a phenotype similar to that due to M-MOK. These features indicate a novel mechanism for energy depletion during lyssavirus-induced apoptosis.
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Insulin-Inducible SMILE Inhibits Hepatic Gluconeogenesis.
Lee, Ji-Min; Seo, Woo-Young; Han, Hye-Sook; Oh, Kyoung-Jin; Lee, Yong-Soo; Kim, Don-Kyu; Choi, Seri; Choi, Byeong Hun; Harris, Robert A; Lee, Chul-Ho; Koo, Seung-Hoi; Choi, Hueng-Sik
2016-01-01
The role of a glucagon/cAMP-dependent protein kinase-inducible coactivator PGC-1α signaling pathway is well characterized in hepatic gluconeogenesis. However, an opposing protein kinase B (PKB)/Akt-inducible corepressor signaling pathway is unknown. A previous report has demonstrated that small heterodimer partner-interacting leucine zipper protein (SMILE) regulates the nuclear receptors and transcriptional factors that control hepatic gluconeogenesis. Here, we show that hepatic SMILE expression was induced by feeding in normal mice but not in db/db and high-fat diet (HFD)-fed mice. Interestingly, SMILE expression was induced by insulin in mouse primary hepatocyte and liver. Hepatic SMILE expression was not altered by refeeding in liver-specific insulin receptor knockout (LIRKO) or PKB β-deficient (PKBβ(-/-)) mice. At the molecular level, SMILE inhibited hepatocyte nuclear factor 4-mediated transcriptional activity via direct competition with PGC-1α. Moreover, ablation of SMILE augmented gluconeogenesis and increased blood glucose levels in mice. Conversely, overexpression of SMILE reduced hepatic gluconeogenic gene expression and ameliorated hyperglycemia and glucose intolerance in db/db and HFD-fed mice. Therefore, SMILE is an insulin-inducible corepressor that suppresses hepatic gluconeogenesis. Small molecules that enhance SMILE expression would have potential for treating hyperglycemia in diabetes. © 2016 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.
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3 cases of radiation-induced sarcoma
International Nuclear Information System (INIS)
Shiba, Keiichiro; Fukuma, Hisatoshi; Beppu, Yasuo; Hirota, Teruyuki; Shinohara, Norio.
1982-01-01
Criteria for the diagnosis of radiation-induced sarcoma have been previously described. All cases must have a history of irradiation and the second neoplasm must have arisen in the area of the radiation field. A latent period of several years must have elapsed after irradiation before clinical evidence of a second malignant neoplasm. Most important thing is that, all suspected cases must have been proved histologically. We have experienced 3 cases of radiation-induced sarcoma, they were 42-years-old man who developed an osteosarcoma of the lumbar spine at the field of postoperative irradiation for seminoma 7 years previously, 69-years-old woman who developed a malignant fibrous histiocytoma of the buttock at the field of radical radiation for uterine carcinoma 7 years previously and 59-years-old woman who developed an extraskeletal osteosarcoma of the abdominal wall at the field of postoperative irradiation for uterine sarcoma 7 years previously. The last case is very rare and only 8 cases of radiation-induced extraskeletal osteosarcoma have been reported. Since there has been a definite trend in the treatment of cancer toward employing radiation for more favorable cases, in addition to technical improvements in the administration of radiotherapy and more modern equipment, survival data may have been altered considerably in many malignant tumors. Accordingly, more radiation-induced tumors may be encountered in the future. The clinical presentation and histopathology of these radiation-induced sarcomas are presented with a review of the literature. (author)
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Mechanisms of cadmium induced genomic instability
Energy Technology Data Exchange (ETDEWEB)
Filipic, Metka, E-mail: metka.filipic@nib.si [National Institute of Biology, Department for Genetic Toxicology and Cancer Biology, Ljubljana (Slovenia)
2012-05-01
Cadmium is an ubiquitous environmental contaminant that represents hazard to humans and wildlife. It is found in the air, soil and water and, due to its extremely long half-life, accumulates in plants and animals. The main source of cadmium exposure for non-smoking human population is food. Cadmium is primarily toxic to the kidney, but has been also classified as carcinogenic to humans by several regulatory agencies. Current evidence suggests that exposure to cadmium induces genomic instability through complex and multifactorial mechanisms. Cadmium dose not induce direct DNA damage, however it induces increase in reactive oxygen species (ROS) formation, which in turn induce DNA damage and can also interfere with cell signalling. More important seems to be cadmium interaction with DNA repair mechanisms, cell cycle checkpoints and apoptosis as well as with epigenetic mechanisms of gene expression control. Cadmium mediated inhibition of DNA repair mechanisms and apoptosis leads to accumulation of cells with unrepaired DNA damage, which in turn increases the mutation rate and thus genomic instability. This increases the probability of developing not only cancer but also other diseases associated with genomic instability. In the in vitro experiments cadmium induced effects leading to genomic instability have been observed at low concentrations that were comparable to those observed in target organs and tissues of humans that were non-occupationally exposed to cadmium. Therefore, further studies aiming to clarify the relevance of these observations for human health risks due to cadmium exposure are needed.
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Mechanisms of cadmium induced genomic instability
International Nuclear Information System (INIS)
Filipič, Metka
2012-01-01
Cadmium is an ubiquitous environmental contaminant that represents hazard to humans and wildlife. It is found in the air, soil and water and, due to its extremely long half-life, accumulates in plants and animals. The main source of cadmium exposure for non-smoking human population is food. Cadmium is primarily toxic to the kidney, but has been also classified as carcinogenic to humans by several regulatory agencies. Current evidence suggests that exposure to cadmium induces genomic instability through complex and multifactorial mechanisms. Cadmium dose not induce direct DNA damage, however it induces increase in reactive oxygen species (ROS) formation, which in turn induce DNA damage and can also interfere with cell signalling. More important seems to be cadmium interaction with DNA repair mechanisms, cell cycle checkpoints and apoptosis as well as with epigenetic mechanisms of gene expression control. Cadmium mediated inhibition of DNA repair mechanisms and apoptosis leads to accumulation of cells with unrepaired DNA damage, which in turn increases the mutation rate and thus genomic instability. This increases the probability of developing not only cancer but also other diseases associated with genomic instability. In the in vitro experiments cadmium induced effects leading to genomic instability have been observed at low concentrations that were comparable to those observed in target organs and tissues of humans that were non-occupationally exposed to cadmium. Therefore, further studies aiming to clarify the relevance of these observations for human health risks due to cadmium exposure are needed.
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Human-induced geomorphic change across environmental gradients
Vanacker, V.; Molina, A.; Bellin, N.; Christl, M.
2016-12-01
Human-induced land cover changes are causing important adverse effects on the ecological services rendered by mountain ecosystems, and the number of case-studies of the impact of humans on soil erosion and sediment yield has mounted rapidly. Anthropogenic disturbance of natural vegetation can profoundly alter the physical, chemical and biological processes within soils. Rapid removal of topsoil during intense farming can result in an imbalance between soil production through chemical weathering and physical soil erosion, with direct implications on nutrient cycling, soil fertility and agricultural production. In this study, we present a conceptual model for assessing human-induced erosion for a wide variety of environmental settings and pose that human-induced geomorphic change cannot be assessed solely based on modern erosion rates as natural or baseline erosion rates can be important in e.g. mountainous terrain. As such, we assess the vulnerability of a given ecosystem to human-induced land cover change by quantifying the change in catchment-wide erosion rates resulting from anthropogenic changes in vegetation cover. Human-induced erosion is here approximated by the ratio of the total specific sediment yield to the natural erosional mass flux, and is dimensionless. The conceptual model is applied to three contrasting environmental settings where data on soil production, physical soil erosion and long-term denudation are available: the tropical Andes, subtropical southern Brazil, and semi-arid Spanish Cordillera. The magnitude of human-induced geomorphic change strongly differs between the three regions. The data suggest that the sensitivity to human-induced erosion is ecosystem dependent, and related to soil erosivity and potential vegetation cover disturbances as a result of human impact. It may therefore be expected that the potential for erosion regulation is larger in well-vegetated ecosystem where strong differences may exist in vegetation cover between
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Clinical oversight and the avoidance of repeat induced abortion.
Jacovetty, Erica L; Clare, Camille A; Squire, Mary-Beatrice; Kubal, Keshar P; Liou, Sherry; Inchiosa, Mario A
2018-06-03
To evaluate the impact of patient counseling, demographics, and contraceptive methods on repeat induced abortion in women attending family planning clinics. A retrospective chart review of repeat induced abortions was performed. The analysis included patients with an initial induced abortion obtained between January 1, 2001, and March 31, 2014, at New York City Health + Hospitals/Metropolitan. The duration of involvement in the family planning program, the use of contraceptive interventions, and 18 patient factors were analyzed for their correlation with the incidence of repeat induced abortions per year of follow-up. A decreased rate of repeat induced abortions was associated with a longer duration of clinical oversight (r 2 =0.449, Pabortions. By determining the patient characteristics that most influence repeat induced abortion rates, providers can best choose the most efficacious method of contraception available. © 2018 International Federation of Gynecology and Obstetrics.
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Csk regulates angiotensin II-induced podocyte apoptosis.
Zhang, Lu; Ren, Zhilong; Yang, Qian; Ding, Guohua
2016-07-01
Increasing data have shown that angiotensin II (Ang II) perpetuates podocyte injury and promotes progression to end-stage kidney disease. The mechanism underlying Ang II-induced podocyte apoptosis has not been established. C-terminal Src kinase (Csk) is a cytoplasmic kinase that interacts with scaffolding proteins involved in cell growth, adhesion, and polarization, and the role of Csk in regulating cellular apoptosis has gradually attracted attention. This study evaluates the role of Csk in Ang II-induced podocyte apoptosis. In vivo, Wistar rats were randomly subjected to a normal saline or Ang II infusion. In vitro, we exposed differentiated mouse podocytes to Ang II. Ang II increased Csk expression and induced podocyte apoptosis, stimulated Csk translocation and binding to Caveolin-1, and stimulated decreased Fyn pY416, increased Fyn pY529, and nephrin dephosphorylation. Csk knockdown prevented Ang II-induced podocyte apoptosis, reduced Fyn kinase inactivation, and increased the interaction between nephrin and the activated form of Fyn, accompanied by a reduced interaction between Csk and Caveolin-1. These findings indicate that Ang II induces podocyte injury via a Csk-dependent pathway.
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PPARα- and DEHP-Induced Cancers
Directory of Open Access Journals (Sweden)
Yuki Ito
2008-01-01
Full Text Available Di(2-ethylhexylphthalate (DEHP is a widely used plasticizer and a potentially nongenotoxic carcinogen. Its mechanism had been earlier proposed based on peroxisome proliferator-activated receptor α (PPARα because metabolites of DEHP are agonists. However, recent evidence also suggests the involvement of non-PPARα multiple pathway in DEHP-induced carcinogenesis. Since there are differences in the function and constitutive expression of PPARα among rodents and humans, species differences are also thought to exist in the carcinogenesis. However, species differences were also seen in the lipase activity involved in the first step of the DEHP metabolism, which should be considered in DEHP-induced carcinogenesis. Taken together, it is very difficult to extrapolate the results from rodents to humans in the case of DEHP carcinogenicity. However, PPARα-null mice or mice with human PPARα gene have been developed, which may lend support to make such a difficult extrapolation. Overall, further mechanical study on DEHP-induced carcinogenicity is warranted using these mice.
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Inducible laryngeal obstruction
DEFF Research Database (Denmark)
Halvorsen, Thomas; Walsted, Emil Schwarz; Bucca, Caterina
2017-01-01
Inducible laryngeal obstruction (ILO) describes an inappropriate, transient, reversible narrowing of the larynx in response to external triggers. ILO is an important cause of a variety of respiratory symptoms and can mimic asthma. Current understanding of ILO has been hampered by imprecise nomenc...
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DEFF Research Database (Denmark)
Stacul, Fulvio; van der Molen, Aart J; Reimer, Peter
2011-01-01
PURPOSE: The Contrast Media Safety Committee (CMSC) of the European Society of Urogenital Radiology (ESUR) has updated its 1999 guidelines on contrast medium-induced nephropathy (CIN). AREAS COVERED: Topics reviewed include the definition of CIN, the choice of contrast medium, the prophylactic me...
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Mokas, Sophie; Larivière, Richard; Lamalice, Laurent; Gobeil, Stéphane; Cornfield, David N; Agharazii, Mohsen; Richard, Darren E
2016-09-01
Medial vascular calcification is a common complication of chronic kidney disease (CKD). Although elevated inorganic phosphate stimulates vascular smooth muscle cell (VSMC) osteogenic transdifferentiation and calcification, the mechanisms involved in their calcification during CKD are not fully defined. Because hypoxic gene activation is linked to CKD and stimulates bone cell osteogenic differentiation, we used in vivo and in vitro rodent models to define the role of hypoxic signaling during elevated inorganic phosphate-induced VSMC calcification. Cell mineralization studies showed that elevated inorganic phosphate rapidly induced VSMC calcification. Hypoxia strongly enhanced elevated inorganic phosphate-induced VSMC calcification and osteogenic transdifferentiation, as seen by osteogenic marker expression. Hypoxia-inducible factor-1 (HIF-1), the key hypoxic transcription factor, was essential for enhanced VSMC calcification. Targeting HIF-1 expression in murine VSMC blocked calcification in hypoxia with elevated inorganic phosphate while HIF-1 activators, including clinically used FG-4592/Roxadustat, recreated a procalcifying environment. Elevated inorganic phosphate rapidly activated HIF-1, even in normal oxygenation; an effect mediated by HIF-1α subunit stabilization. Thus, hypoxia synergizes with elevated inorganic phosphate to enhance VSMC osteogenic transdifferentiation. Our work identifies HIF-1 as an early CKD-related pathological event, prospective marker, and potential target against vascular calcification in CKD-relevant conditions. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.
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The nature and principles of the radiation-induced cancerogenesis
International Nuclear Information System (INIS)
Lips'ka, A.YI.; Serkyiz, Ya.Yi.
2004-01-01
The paper represents the analysis of the authors and literary data concerning the nature and principles of the radiation-induced neoplasms. The mechanisms of the radiation-induced cancerogenesis development are not clear understood. The experimental data altogether do not allow developing the mathematical model of the radiation-induced cancerogenesis at the molecular level. This model has to take into account all necessary indices including radiation factor and the state of the organism. The general principles of the radiation-induced cancerogenesis have been formulated in the present review. It is possible to use these principles in order to predict and calculate the risks of the radiation-induced neoplasms
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Prolonged drug-induced hypothermia in experimental stroke
DEFF Research Database (Denmark)
Johansen, Flemming Fryd; Jørgensen, Henrik Stig; Reith, Jakob
2007-01-01
In experimental and human stroke, hypothermia is strongly related to a favorable outcome. Previous attempts to manipulate the core temperature in focal cerebral ischemia have been based on mechanical cooling. The purpose of the study is to establish a model for long-term drug-induced hypothermia...... in focal ischemia by pharmacological alteration of the central thermoregulatory set-point. We tested the hypothesis that the dopaminergic agonist Talipexole, which induces hypothermia, reduces infarct size. Body temperature was monitored by a radio-pill-implant. Rats had reversible occlusion of the middle...... that the core body temperature was reduced by 1.7 degrees C for 24 hours after MCAO in rats treated with Talipexole. This treatment induced a significant reduction of infarct volume at 7 days after focal ischemia by 47%. We suggest that the reduction in infarct volume is related to drug-induced hypothermia...
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[Hydroxyurea-induced pneumonia].
Girard, A; Ricordel, C; Poullot, E; Claeyssen, V; Decaux, O; Desrues, B; Delaval, P; Jouneau, S
2014-05-01
Hydroxyurea is an antimetabolite drug used in the treatment of myeloproliferative disorders. Common adverse effects include haematological, gastrointestinal cutaneous manifestations, and fever. Hydroxyurea-induced pneumonitis is unusual. A female patient was treated with hydroxyurea for polycythemia vera. She was admitted 20 days after commencing treatment with a high fever, productive cough, clear sputum and nausea. A chest CT-scan showed diffuse ground-glass opacities. Microbiological investigations were negative. The symptoms disappeared a few days after discontinuation of the drug and rechallenge led to a relapse of symptoms. Our case and 15 earlier cases of hydroxyurea-induced pneumonitis are reviewed. Two patterns of this disease may exist: an acute febrile form occurring within 1 month of introduction of hydroxyurea and a subacute form without fever. Even if uncommon, one should be aware of this complication of hydroxyurea. Copyright © 2013. Published by Elsevier Masson SAS.
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Neonicotinoid insecticides induce salicylate-associated plant defense responses
Ford, Kevin A.; Casida, John E.; Chandran, Divya; Gulevich, Alexander G.; Okrent, Rachel A.; Durkin, Kathleen A.; Sarpong, Richmond; Bunnelle, Eric M.; Wildermuth, Mary C.
2010-01-01
Neonicotinoid insecticides control crop pests based on their action as agonists at the insect nicotinic acetylcholine receptor, which accepts chloropyridinyl- and chlorothiazolyl-analogs almost equally well. In some cases, these compounds have also been reported to enhance plant vigor and (a)biotic stress tolerance, independent of their insecticidal function. However, this mode of action has not been defined. Using Arabidopsis thaliana, we show that the neonicotinoid compounds, imidacloprid (IMI) and clothianidin (CLO), via their 6-chloropyridinyl-3-carboxylic acid and 2-chlorothiazolyl-5-carboxylic acid metabolites, respectively, induce salicylic acid (SA)-associated plant responses. SA is a phytohormone best known for its role in plant defense against pathogens and as an inducer of systemic acquired resistance; however, it can also modulate abiotic stress responses. These neonicotinoids effect a similar global transcriptional response to that of SA, including genes involved in (a)biotic stress response. Furthermore, similar to SA, IMI and CLO induce systemic acquired resistance, resulting in reduced growth of a powdery mildew pathogen. The action of CLO induces the endogenous synthesis of SA via the SA biosynthetic enzyme ICS1, with ICS1 required for CLO-induced accumulation of SA, expression of the SA marker PR1, and fully enhanced resistance to powdery mildew. In contrast, the action of IMI does not induce endogenous synthesis of SA. Instead, IMI is further bioactivated to 6-chloro-2-hydroxypyridinyl-3-carboxylic acid, which is shown here to be a potent inducer of PR1 and inhibitor of SA-sensitive enzymes. Thus, via different mechanisms, these chloropyridinyl- and chlorothiazolyl-neonicotinoids induce SA responses associated with enhanced stress tolerance. PMID:20876120