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1.
Rev. bras. ciênc. avic ; 24(2): eRBCA-2021-1553, abr. 2022. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1368495

RESUMEN

Heat stress compromises turkey's productivity and increase mortality mainly in the final stages of growth. This study evaluated the effect of perches and its interaction with outdoor access on turkey performance in high environment temperature humidity index (THI). Turkeys were reared in 1.75 × 5 m indoor floor pens and were fed with a standard commercial diet, offered ad libitum according to the productive phase. All poults were housed indoors until 62 d of age. A free-range area for a replicate of 8.75 m2, with natural shadow, was available from 07:00 to 19:00 h. Final density was 10.33 ± 0.22 kg/m2. The treatments were a combination of a factorial arrangement (2 × 2) with or without perches and, with or without access to the outdoors. From 10:00 and 19:00 THI was above critical level of comfort (heat stress). In indoors turkeys, feed intake (FI) decreased, and water intake increased, panting was observed, and had a significantly lower final body weight (BW) and FI than turkeys allowed outdoors (p<0.05). Perch availability decreased final BW and FI (p<0.05). Differences in weight of breast meat, wings, or thighs between treatments were negligible. In conclusion turkeys with outdoor access from 62 d of age had better performance.(AU)


Asunto(s)
Animales , Pavos/fisiología , Respuesta al Choque Térmico , Fenómenos Fisiológicos Nutricionales de los Animales , Peso Corporal
2.
Cryo Letters ; 41(1): 13-18, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33973979

RESUMEN

BACKGROUND: ATP exogenous (ATPe) has been used successfully in improving motility and fertility for many animal species. However this has not yet been tested on Brycon orbignyamus. OBJECTIVE: The objective of this study was to evaluate the use of ATPe for the cryopreservation of sperm from B. orbignyamus. MATERIALS AND METHODS: The ATPe concentrations tested were 1.0 µM, 5.0 µM and 10 µM combined with Beltsville Thawing SolutionTM extender and dimethylformamide at 7.5%. The sperm were frozen in a nitrogen vapour vessel and stored in liquid nitrogen at -196 ºC. The parameters of viability post-thawing were evaluated using CASA, and flow cytometer. RESULTS: The ATPe did not promote improvements in spermatic kinetics, and in the higher concentrations caused a worsening in these parameters. Also there was loss of mitochondrial functionality and greater cellular disruption with the concentration of 10 µM. CONCLUSION: We do not recommend the addition of ATP for cryopreserving B. orbignyamus.


Asunto(s)
Adenosina Trifosfato , Characiformes , Criopreservación , Crioprotectores , Preservación de Semen , Adenosina Trifosfato/farmacología , Animales , Criopreservación/veterinaria , Crioprotectores/farmacología , Masculino , Preservación de Semen/veterinaria , Motilidad Espermática , Espermatozoides
3.
R. bras. Ci. avíc. ; 22(1): eRBCA-2019-1167, 2020. tab, ilus
Artículo en Inglés | VETINDEX | ID: vti-27483

RESUMEN

Natural antimicrobials, known as phytobiotics, are used in bacterial infections. The objective of this study was to evaluatethe phytobiotic activity, in vitro and in vivo, of an extract and an essential oil of Piper auritum and Ocimum basilicum on avian Eschericia coli serotype O2 in broiler chickens experimentally infected. For the in vitro test, extracts at 4, 8, 12 and 16% in water-based solvent or alcohol at 70% were prepared from leaves of both plants. In the essential oils, solvents at 10% were used. A concentration of 1×108 CFU mL-1 of bacteria was seeded and on each sense disc, 25 µL of the extract or essential oil were poured, except on the positive or negative control. The diameter of the inhibition zone (DIZ) of bacterial growth was measured. In the in vivo test, 40 chickens were inoculated, by intratracheal route, with a bacterial suspension of 1 × 108 CFU mL-1. E. col was identified and isolated from the organs; mortality, morbidity and relative weight of the organs were measured, and postmortem lesions and histopathologic findings were observed. A completely randomized design and the Kruskal-Wallis test for data analysis was used. By increasing the concentration of the extract, DIZ was greater; at the time of slaughter, differences in body weight (p 0.05) were found and the majority of lesions were observed in lungs. It is concluded that leave extracts of P. auritum and O. basilicum had phytobiotic activity on E. col serotype O2.(AU)


Asunto(s)
Animales , Ocimum/microbiología , Pollos/microbiología , Piper/microbiología , Escherichia coli/patogenicidad
4.
Rev. bras. ciênc. avic ; 22(1): eRBCA, 2020. tab, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1490749

RESUMEN

Natural antimicrobials, known as phytobiotics, are used in bacterial infections. The objective of this study was to evaluatethe phytobiotic activity, in vitro and in vivo, of an extract and an essential oil of Piper auritum and Ocimum basilicum on avian Eschericia coli serotype O2 in broiler chickens experimentally infected. For the in vitro test, extracts at 4, 8, 12 and 16% in water-based solvent or alcohol at 70% were prepared from leaves of both plants. In the essential oils, solvents at 10% were used. A concentration of 1×108 CFU mL-1 of bacteria was seeded and on each sense disc, 25 µL of the extract or essential oil were poured, except on the positive or negative control. The diameter of the inhibition zone (DIZ) of bacterial growth was measured. In the in vivo test, 40 chickens were inoculated, by intratracheal route, with a bacterial suspension of 1 × 108 CFU mL-1. E. col was identified and isolated from the organs; mortality, morbidity and relative weight of the organs were measured, and postmortem lesions and histopathologic findings were observed. A completely randomized design and the Kruskal-Wallis test for data analysis was used. By increasing the concentration of the extract, DIZ was greater; at the time of slaughter, differences in body weight (p 0.05) were found and the majority of lesions were observed in lungs. It is concluded that leave extracts of P. auritum and O. basilicum had phytobiotic activity on E. col serotype O2.


Asunto(s)
Animales , Escherichia coli/patogenicidad , Pollos/microbiología , Ocimum/microbiología , Piper/microbiología
5.
Clin Transl Oncol ; 20(10): 1289-1301, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29623582

RESUMEN

BACKGROUND: Lymphoma is the third most common malignancy in children (0-14 years) and the first in adolescents (15-19 years). This population-based study-the largest ever done in Spain-analyses incidence and survival of lymphomas among Spanish children and adolescents. PATIENTS AND METHODS: 1664 lymphoma cases (1983-2007) for incidence and 1030 for survival (1991-2005) followed until 31/12/2010, were provided by 11 cancer registries. Age-adjusted incidence rates (ASRw) to the world standard population were obtained; incidence trends were modelled using the Joinpoint programme, observed survival (OS) was estimated with Kaplan-Meier and trends tested with a log-rank test. Results are presented according to the International Classification of Childhood Cancer-3. RESULTS: In Spain, the ASRw0-14 for lymphomas was 17.5 per 1.000.000 child-years and 50.0 the specific rate for adolescents. Overall incidence increased significantly during 1983-1997 with no increases thereafter. Patients over 9 years old showed significant rising trends for all subtypes, except for Burkitt lymphoma (BL) in adolescents. During 2001-2005 (age 0-19 years), 5-year OS was 94 (90-98), 73 (64-83) and 86 (78-94) for Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL) and BL, respectively. No improvement in survival was found. The incidence in Spain was higher than overall European rates, but within the range of that in Southern Europe. Comparing OS in Spain 1991-1995 and 2001-2005 with results for Europe of the Automated Childhood Cancer Information System (ACCIS) (1988-1997) and the European cancer registry-based study on survival and care of cancer patients (EUROCARE) (2000-2007), it was similar for HL and lower for NHL and BL. CONCLUSIONS: Systematic monitoring and analysis of lymphoma paediatric data would provide clinical and epidemiological information to improve the health care of these patients and the outcomes for these malignancies in Spain.


Asunto(s)
Linfoma/epidemiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Estimación de Kaplan-Meier , Masculino , Sistema de Registros , España/epidemiología
6.
Chemosphere ; 186: 88-99, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28772185

RESUMEN

The adverse effects of endocrine disrupting chemicals (EDCs) on aquatic wildlife and human health represent a current issue of high public concern. Even so, they are still poorly studied in aquatic environments of South America. The aim of the present study was to investigate the impact of EDCs in five cascading reservoirs from the Iguaçu River, evaluating reproductive endpoints in three native fish species (Astyanax bifasciatus, Chrenicicla iguassuensis and Geophagus brasiliensis). Additionally, a polyclonal antiserum anti-vitellogenin from G. brasiliensis and a capture ELISA assay were developed for detection of estrogenic or anti-estrogenic activities in male and female fish, respectively. Vitellogenin (VTG) levels in male fish from the Iguacu River was observed, as well as decreased levels of vitellogenin and estradiol in the plasma of female fish. These findings were associated with immature gonads and lower gonadosomatic index in G. brasiliensis adult females from the Foz do Areia (FA) Reservoir. Additionally, both endemic species (Astyanax bifasciatus and Chrenicicla iguassuensis) displayed immature gonads and histological changes, such as degeneration of germ cells, in other studied reservoirs. The current results suggest that these reproductive responses may be associated with the bioavailability of EDCs in the Iguaçu River. These impacts are likely related to chemicals released by human activities, especially from sewage and industrial sources and agricultural production, detected in previous studies. Overall, the FA reservoir was potentially the most affected by chemicals with endocrine properties, and further studies are necessary to identify and quantify these chemicals.


Asunto(s)
Biomarcadores/metabolismo , Disruptores Endocrinos/toxicidad , Monitoreo del Ambiente , Peces/fisiología , Vitelogeninas/metabolismo , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/análisis , Brasil , Cíclidos , Disruptores Endocrinos/análisis , Sistema Endocrino/efectos de los fármacos , Estradiol/análisis , Estrona/análisis , Femenino , Gónadas/efectos de los fármacos , Gónadas/fisiología , Masculino , Reproducción/efectos de los fármacos , Ríos/química , Aguas del Alcantarillado/efectos adversos , Vitelogeninas/sangre , Contaminantes Químicos del Agua/análisis
7.
Fish Physiol Biochem ; 43(5): 1237-1244, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28389904

RESUMEN

Cylindrospermopsin (CYN) is a cyanotoxin that is cytotoxic to a wide variety of cells, particularly to the hepatocytes. In this study, the toxic effects of purified CYN were investigated in primary cultured hepatocytes of Neotropical fish Hoplias malabaricus. After isolation, attachment, and recovery for 72 h, the cells were exposed for 72 h to 0, 0.1, 1.0, 10, and 100 µg l-1 of CYN. Then, cell viability and a set of oxidative stress biomarker responses were determined. Catalase, superoxide dismutase, glucose-6-phosphate dehydrogenase, and glutathione S-transferase activities were not affected by exposure to CYN. Concentration-dependent decrease of glutathione reductase activity occurred for most CYN-exposed groups, whereas non-protein thiol content increased only for the highest CYN concentration. Lipid peroxidation, protein carbonylation, and DNA damage levels were not altered, but reactive oxygen species levels increased in the cells exposed to the highest concentration of CYN. Cell viability decreased in all the groups exposed to CYN. Thus, CYN may cause a slight change in redox balance, but it is not the main cause of cell death in H. malabaricus hepatocytes.


Asunto(s)
Toxinas Bacterianas/farmacología , Supervivencia Celular/efectos de los fármacos , Characiformes , Hepatocitos/efectos de los fármacos , Uracilo/análogos & derivados , Alcaloides , Animales , Toxinas Bacterianas/administración & dosificación , Biomarcadores , Células Cultivadas , Toxinas de Cianobacterias , Relación Dosis-Respuesta a Droga , Estrés Oxidativo/efectos de los fármacos , Uracilo/administración & dosificación , Uracilo/farmacología
8.
Clin Transl Oncol ; 19(3): 301-316, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27447899

RESUMEN

OBJECTIVE: We have analysed incidence and survival trends of children and adolescents with leukaemia registered in Spanish population-based cancer registries during the period 1983-2007. METHODS: Childhood and adolescent leukaemia cases were drawn from the 11 Spanish population-based cancer registries. For survival, registries with data for the period 1991-2005 and follow-up until 31-12-2010 were included. Overall incidence trends were evaluated using joinpoint analysis. Observed survival rates were estimated using Kaplan-Meier, and trends were tested using the log-rank test. RESULTS: Based on 2606 cases (2274 children and 332 adolescents), the overall age-adjusted incidence rate (ASRw) of leukaemia was 47.9 cases per million child-years in children and 23.8 in adolescents. The ASRw of leukaemia increased with an annual percentage change of 9.6 % (95 % CI: 2.2-17.6) until 1990 followed by a stabilisation of rates. In adolescents, incidence did not increase. Five-year survival increased from 66 % in 1991-1995 to 76 % in 2001-2005. By age, survival was dramatically lower in infants (0) and adolescents (15-19) than in the other age groups and no improvement was observed. In both children and adolescents, differences in 5-year survival rates among major subgroups of leukaemias were significant. CONCLUSIONS: The increasing incidence trends observed in childhood leukaemias during the study period were confined to the beginning of the period. Remarkable improvements in survival have been observed in Spanish children with leukaemias. However, this improvement was not observed in infants and adolescents.


Asunto(s)
Leucemia/epidemiología , Leucemia/mortalidad , Sistema de Registros/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Estadificación de Neoplasias , Pronóstico , España/epidemiología , Tasa de Supervivencia , Factores de Tiempo , Adulto Joven
9.
Environ Sci Pollut Res Int ; 23(6): 5179-88, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26555884

RESUMEN

The impact of nanoparticles on fish health is still a matter of debate, since nanotechnology is quite recent. In this study, freshwater benthonic juvenile fish Prochilodus lineatus were exposed through water to three concentrations of TiO2 (0.1, 1, and 10 µg l(-1)) and ZnO (7, 70, and 700 µg l(-1)) nanoparticles, as well as to a mixture of both (TiO2 1 µg l(-1) + ZnO 70 µg l(-1)) for 5 and 30 days. Nanoparticle characterization revealed an increase of aggregate size in the function of concentration, but suspensions were generally stable. Fish mortality was high at subchronic exposure to 70 and 700 µg l(-1) of ZnO. Nanoparticle exposure led to decreased acetylcholinesterase activity either in the muscle or in the brain, depending on particle composition (muscle-TiO2 10 µg l(-1); brain-ZnO 7 and 700 µg l(-1)), and protein oxidative damage increased in the brain (ZnO 70 µg l(-1)) and gills (ZnO 70 µg l(-1) and mixture) but not in the liver. Exposed fish had more frequent alterations in the liver (necrosis, vascular congestion, leukocyte infiltration, and basophilic foci) and gills (hyperplasia and epithelial damages, e.g., epithelial disorganization and epithelial loss) than the control fish. Thus, predicted concentrations of TiO2 and ZnO nanoparticles caused detectable effects on P. lineatus that may have important consequences to fish health. But, these effects are much more subtle than those usually reported in the scientific literature for high concentrations or doses of metal nanoparticles.


Asunto(s)
Peces , Nanopartículas del Metal/toxicidad , Titanio/toxicidad , Contaminantes Químicos del Agua/toxicidad , Óxido de Zinc/toxicidad , Animales , Agua Dulce , Branquias/efectos de los fármacos , Branquias/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Contaminantes Químicos del Agua/metabolismo
10.
Braz J Biol ; 75(4 Suppl 1): S245-52, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26628218

RESUMEN

Several environmental parameters may influence biological processes of several aquatic invertebrates, such as the Monogenea. Current analysis investigates oviposition, hatching success and infestation of Aphanoblastella mastigatus, a parasite of the silver catfish Rhamdia quelen at different temperatures (~ 24 and 28 °C) and salinity (by adding sodium chloride to water, at concentrations 0, 5 and 9 g/L) in laboratory. There was no significant difference in oviposition rate and in A. mastigatus infestation success at 24 and 28 °C. On the other hand, the concentration 9 g/L of sodium chloride in the water impaired the parasite's survival and the viability of the eggs. Results show that its usage is efficient as a possible prophylactic treatment. Eclosion rate of A. mastigatus's eggs was significantly higher at 28 °C, although it was significantly less from 5 g/L. Two oviposition peaks (06h15 and 18h15) occurred during a 24-hour period, or rather, during the highest variations in luminosity. Further studies are recommended with greater temperature intervals and more intense experimental infestations to verify the effects of temperature in the life span and infestation success of A. mastigatus.


Asunto(s)
Bagres , Enfermedades de los Peces/epidemiología , Trematodos/fisiología , Infecciones por Trematodos/veterinaria , Animales , Brasil/epidemiología , Femenino , Enfermedades de los Peces/parasitología , Oviposición , Reproducción , Salinidad , Cloruro de Sodio/farmacología , Temperatura , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/parasitología , Agua/química
11.
Braz. j. biol ; Braz. j. biol;75(4)Nov. 2015.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468346

RESUMEN

Abstract Several environmental parameters may influence biological processes of several aquatic invertebrates, such as the Monogenea. Current analysis investigates oviposition, hatching success and infestation of Aphanoblastella mastigatus, a parasite of the silver catfish Rhamdia quelen at different temperatures (~ 24 and 28 °C) and salinity (by adding sodium chloride to water, at concentrations 0, 5 and 9 g/L) in laboratory. There was no significant difference in oviposition rate and in A. mastigatus infestation success at 24 and 28 °C. On the other hand, the concentration 9 g/L of sodium chloride in the water impaired the parasites survival and the viability of the eggs. Results show that its usage is efficient as a possible prophylactic treatment. Eclosion rate of A. mastigatuss eggs was significantly higher at 28 °C, although it was significantly less from 5 g/L. Two oviposition peaks (06h15 and 18h15) occurred during a 24-hour period, or rather, during the highest variations in luminosity. Further studies are recommended with greater temperature intervals and more intense experimental infestations to verify the effects of temperature in the life span and infestation success of A. mastigatus.


Resumo Diversos parâmetros ambientais podem afetar os processos biológicos de diversos organismos invertebrados aquáticos, como os Monogenea. Neste estudo, nós investigamos a oviposição, sucesso de eclosão e infestação de Aphanoblastella mastigatus, parasito de jundiá Rhamdia quelen, em diferentes condições de temperatura (~ 24 e 28 °C) e salinidade (por meio da adição de cloreto de sódio na água nas concentrações de 0, 5 e 9 g/L) em laboratório. Não houve diferença significativa na taxa de oviposição nem no sucesso de infestação de A. mastigatus à 24 e 28 °C; por outro lado, a concentração de 9 g/L de cloreto de sódio na água inviabilizou não só a sobrevivência do parasito mas também a viabilidade dos ovos. Esse resultado indica que seu uso é eficiente como potencial tratamento profilático. A taxa de eclosão dos ovos de A. mastigatus foi significativamente maior a 28 °C. A partir de 5 g/L, a mesma foi significativamente menor. Durante um período de 24 horas, dois picos na oviposição ocorreram nos momentos de maior variação da luminosidade (06h15 e 18h15). Futuros estudos são recomendados utilizando intervalos de temperatura e intensidades de infestação experimental maiores para verificar a influência da temperatura na longevidade e sucesso de infestação de A. mastigatus.

12.
Braz. j. biol ; Braz. j. biol;75(4,supl.1): 245-252, Nov. 2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-768219

RESUMEN

Abstract Several environmental parameters may influence biological processes of several aquatic invertebrates, such as the Monogenea. Current analysis investigates oviposition, hatching success and infestation of Aphanoblastella mastigatus, a parasite of the silver catfish Rhamdia quelen at different temperatures (~ 24 and 28 °C) and salinity (by adding sodium chloride to water, at concentrations 0, 5 and 9 g/L) in laboratory. There was no significant difference in oviposition rate and in A. mastigatus infestation success at 24 and 28 °C. On the other hand, the concentration 9 g/L of sodium chloride in the water impaired the parasite’s survival and the viability of the eggs. Results show that its usage is efficient as a possible prophylactic treatment. Eclosion rate of A. mastigatus’s eggs was significantly higher at 28 °C, although it was significantly less from 5 g/L. Two oviposition peaks (06h15 and 18h15) occurred during a 24-hour period, or rather, during the highest variations in luminosity. Further studies are recommended with greater temperature intervals and more intense experimental infestations to verify the effects of temperature in the life span and infestation success of A. mastigatus.


Resumo Diversos parâmetros ambientais podem afetar os processos biológicos de diversos organismos invertebrados aquáticos, como os Monogenea. Neste estudo, nós investigamos a oviposição, sucesso de eclosão e infestação de Aphanoblastella mastigatus, parasito de jundiá Rhamdia quelen, em diferentes condições de temperatura (~ 24 e 28 °C) e salinidade (por meio da adição de cloreto de sódio na água nas concentrações de 0, 5 e 9 g/L) em laboratório. Não houve diferença significativa na taxa de oviposição nem no sucesso de infestação de A. mastigatus à 24 e 28 °C; por outro lado, a concentração de 9 g/L de cloreto de sódio na água inviabilizou não só a sobrevivência do parasito mas também a viabilidade dos ovos. Esse resultado indica que seu uso é eficiente como potencial tratamento profilático. A taxa de eclosão dos ovos de A. mastigatus foi significativamente maior a 28 °C. A partir de 5 g/L, a mesma foi significativamente menor. Durante um período de 24 horas, dois picos na oviposição ocorreram nos momentos de maior variação da luminosidade (06h15 e 18h15). Futuros estudos são recomendados utilizando intervalos de temperatura e intensidades de infestação experimental maiores para verificar a influência da temperatura na longevidade e sucesso de infestação de A. mastigatus.


Asunto(s)
Animales , Femenino , Bagres , Enfermedades de los Peces/epidemiología , Trematodos/fisiología , Infecciones por Trematodos/veterinaria , Brasil/epidemiología , Enfermedades de los Peces/parasitología , Oviposición , Reproducción , Salinidad , Cloruro de Sodio/farmacología , Temperatura , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/parasitología , Agua/química
13.
Braz. J. Biol. ; 75(4,supl.1): 245-252, Nov. 2015. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-378915

RESUMEN

Several environmental parameters may influence biological processes of several aquatic invertebrates, such as the Monogenea. Current analysis investigates oviposition, hatching success and infestation of Aphanoblastella mastigatus, a parasite of the silver catfish Rhamdia quelen at different temperatures (~ 24 and 28 °C) and salinity (by adding sodium chloride to water, at concentrations 0, 5 and 9 g/L) in laboratory. There was no significant difference in oviposition rate and in A. mastigatus infestation success at 24 and 28 °C. On the other hand, the concentration 9 g/L of sodium chloride in the water impaired the parasites survival and the viability of the eggs. Results show that its usage is efficient as a possible prophylactic treatment. Eclosion rate of A. mastigatuss eggs was significantly higher at 28 °C, although it was significantly less from 5 g/L. Two oviposition peaks (06h15 and 18h15) occurred during a 24-hour period, or rather, during the highest variations in luminosity. Further studies are recommended with greater temperature intervals and more intense experimental infestations to verify the effects of temperature in the life span and infestation success of A. mastigatus.(AU)


Diversos parâmetros ambientais podem afetar os processos biológicos de diversos organismos invertebrados aquáticos, como os Monogenea. Neste estudo, nós investigamos a oviposição, sucesso de eclosão e infestação de Aphanoblastella mastigatus, parasito de jundiá Rhamdia quelen, em diferentes condições de temperatura (~ 24 e 28 °C) e salinidade (por meio da adição de cloreto de sódio na água nas concentrações de 0, 5 e 9 g/L) em laboratório. Não houve diferença significativa na taxa de oviposição nem no sucesso de infestação de A. mastigatus à 24 e 28 °C; por outro lado, a concentração de 9 g/L de cloreto de sódio na água inviabilizou não só a sobrevivência do parasito mas também a viabilidade dos ovos. Esse resultado indica que seu uso é eficiente como potencial tratamento profilático. A taxa de eclosão dos ovos de A. mastigatus foi significativamente maior a 28 °C. A partir de 5 g/L, a mesma foi significativamente menor. Durante um período de 24 horas, dois picos na oviposição ocorreram nos momentos de maior variação da luminosidade (06h15 e 18h15). Futuros estudos são recomendados utilizando intervalos de temperatura e intensidades de infestação experimental maiores para verificar a influência da temperatura na longevidade e sucesso de infestação de A. mastigatus.(AU)


Asunto(s)
Animales , Femenino , Bagres , Enfermedades de los Peces/epidemiología , Trematodos/fisiología , Infecciones por Trematodos/veterinaria , Brasil/epidemiología , Enfermedades de los Peces/parasitología , Oviposición , Reproducción , Salinidad , Cloruro de Sodio/farmacología , Temperatura , Infecciones por Trematodos/epidemiología , Infecciones por Trematodos/parasitología , Agua/química
14.
Appl Opt ; 52(22): E22-7, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-23913083

RESUMEN

Electrical and nonlinear optical experiments were performed on multiwall carbon nanotubes (CNTs) prepared by a chemical vapor deposition method. We report that the incorporation of platinum particles on the CNTs surface originates an enhancement in the photoconductive properties with noticeable capabilities to modulate optical and electrical signals. The photoconductive logic gate function OR was experimentally demonstrated using a simple photoconductive platform based on our samples. A two-photon absorption effect was identified as the main mechanism of third-order optical nonlinearity under a nonresonant nanosecond excitation. Multiphotonic interactions were described in order to explain the observed behavior.

15.
Toxicol In Vitro ; 25(7): 1493-500, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21600976

RESUMEN

Cylindrospermopsin is a potent toxicant for eukaryotic cells produced by several cyanobacteria. Recently, primary hepatocyte cultures of Neotropical fish have been established, demonstrating to be a quite efficient in vitro model for cellular toxicology studies. In the current study, a protocol for culture of Prochilodus lineatus hepatocytes was established and utilized to investigate the cellular responses to purified cylindrospermopsin exposure. Hepatocytes were successfully dissociated with dispase, resulting in a cell yield of 6.36 × 10(7)cells g(-1) of liver, viability of 97% and attachment on uncoated culture flasks. For investigation of cylindrospermopsin effects, hepatocytes were dissociated, cultured during 96 h and exposed to three concentrations of the toxin (0.1, 1.0 or 10 µgl(-1)) for 72 h. Cylindrospermopsin exposure significantly decreased cell viability (0.1 and 1 µgl(-1)) and multixenobiotic resistance mechanism, MXR (all exposed groups), but increased reactive oxygen/nitrogen species levels (all exposed groups) and lipid peroxidation (10 µgl(-1)). On the other hand no significant alterations were observed for other biochemical biomarkers as 2GSH/GSSG ratio, protein carbonyl levels and DNA strand breaks or glutathione S-transferase and glucose 6-phosphate dehydrogenase activities. In conclusion, hepatocytes might be made sensitive to cylindrospermopsin, at least in part, due to reduction of xenobiotics and endobiotics efflux capacity by MXR. Additionally, the toxin exposure suggests important issues regarding hepatocytes survival at the lowest cylindrospermopsin concentrations.


Asunto(s)
Characiformes/fisiología , Hepatocitos/efectos de los fármacos , Uracilo/análogos & derivados , Contaminantes Químicos del Agua/toxicidad , Alcaloides , Animales , Toxinas Bacterianas , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Toxinas de Cianobacterias , Daño del ADN , Relación Dosis-Respuesta a Droga , Hepatocitos/citología , Hepatocitos/metabolismo , Uracilo/toxicidad
16.
Rev. argent. endocrinol. metab ; Rev. argent. endocrinol. metab;48(1): 52-52, ene.-mar. 2011.
Artículo en Español | LILACS | ID: lil-641992
17.
Comp Biochem Physiol C Toxicol Pharmacol ; 151(2): 248-57, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19897053

RESUMEN

This study investigated the effects of different doses of 17-beta-estradiol (E(2)) in Rhamdia quelen. Groups of males exposed to different doses of E(2) (0.1 mg kg(-)(1), 1 mg kg(-)(1) and 10 mg kg(-)(1)) were compared with non-exposed male and female fish groups. Among the considered biomarkers, no significant differences were observed for micronuclei test, reduced glutathione concentration and lipid peroxidation. All E(2)-treated individuals had decreased glutathione S-transferase activity. Increased catalase and superoxide dismutase activities, increased vitellogenin expression and decreased metallothionein concentration were observed in males treated with the highest dose. Liver of all test groups showed necrotic areas, but cytoplasm vacuolization was again found only in the individuals exposed to highest dose. E(2) causes deleterious hepatic effects to R. quelen, and vitellogenin expression, catalase and superoxide dismutase activity and metallothionein concentration represent appropriate biomarkers for studying E(2) effects. Additionally, the response of some biomarkers was similar in males exposed to E(2) and unexposed females, and therefore exposure to endocrine disruptors may cause consequences for fish populations.


Asunto(s)
Bagres/fisiología , Estradiol/toxicidad , Vitelogénesis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Western Blotting , Catalasa/metabolismo , Relación Dosis-Respuesta a Droga , Electroforesis en Gel de Poliacrilamida , Estrógenos/toxicidad , Femenino , Agua Dulce , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Transferasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Masculino , Metalotioneína/metabolismo , Pruebas de Micronúcleos , Necrosis , Superóxido Dismutasa/metabolismo , Vitelogénesis/fisiología , Vitelogeninas/metabolismo
18.
Educ. med. super ; 23(1)ene.-mar. 2009. tab
Artículo en Español | LILACS | ID: lil-575512

RESUMEN

Se presentaron los elementos fundamentales de un programa de entrenamiento de posgrado dirigido a los profesionales cubanos para la operación de los equipos automatizados que están siendo instalados en los centros médicos diagnósticos de alta tecnología en Venezuela.


Main elements of a postgraduate training program were introduced, which is aimed to Cuban professional for manage of automated equipments being installed in high tech diagnosis medical centers in Venezuela.


Asunto(s)
Automatización , Equipos y Suministros
19.
J Nanosci Nanotechnol ; 8(5): 2703-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18572712

RESUMEN

The influence of the deposition conditions on the structural features and electrochromic properties of nickel oxide (NiO) films prepared by chemical vapor deposition has been investigated. NiO films have been prepared on fluorine doped tin oxide (FTO) coated glass substrates from nickel-acetylacetonate precursor and their electrochromic properties have been studied by cyclic voltammetry in a 0.1 M KOH solution at room temperature. Films exhibiting only the NiO phase were obtained at deposition temperatures higher than 450 degrees C in a wide range of reactor pressures (0.13 to 66.6 kPa). Particularly, NiO films prepared at 500-550 degrees C from 0.13 to 53.3 kPa are transparent in nature and exhibit a crystallite size varying from 10 to 60 nm. An appreciable anodic electrochromic change from transparent to black coloured resulted from a very porous surface morphology and film thickness of about 3.5 microm. The electrochromic change was maintained over 3000 switching cycles. Nanostructured 3.5 microm-thick NiO films showed a maximum difference in optical transmittance of about 40% in the near-infrared region. These results make the nanostructured NiO films comparables with those prepared by other deposition techniques.

20.
Blood Cells Mol Dis ; 41(1): 91-4, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18203634

RESUMEN

The effects of the CYP1A1*2A genotype on susceptibility to leukemia have received particular attention in recent years because this enzyme plays a central role in the activation of carcinogens. Several polymorphisms at the CYP1A1 locus have been identified and their genotypes appear to exhibit population frequencies that depend on ethnicity. We evaluated the role of the CYP1A1*2A genotype in adults with acute lymphoblastic leukemia (ALL) by genotyping 210 patients and 228 healthy controls from the Mexican population. The frequency of the CC genotype was 8% (18/228) in the control group and 42% (88/210) in ALL patients; the frequency of the CT genotype was 39% (89/228) and 29.5% (62/210), respectively; and that of the TT genotype was 53% (121/228) and 28.5% (60/210), respectively. The odds ratio was 8.4 (95% CI, 4.7-15.5; P < 0.001). These data indicate that the CYP1A1*2A genotype contributes significantly to susceptibility to adult ALL in a sample of the Mexican population.


Asunto(s)
Citocromo P-450 CYP1A1/genética , Predisposición Genética a la Enfermedad , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Femenino , Genotipo , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiología
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