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1.
Eur Phys J E Soft Matter ; 42(7): 86, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31289962

RESUMO

This paper describes the European Space Agency (ESA) experiments devoted to study thermodiffusion of fluid mixtures in microgravity environment, where sedimentation and convection do not affect the mass flow induced by the Soret effect. First, the experiments performed on binary mixtures in the IVIDIL and GRADFLEX experiments are described. Then, further experiments on ternary mixtures and complex fluids performed in DCMIX and planned to be performed in the context of the NEUF-DIX project are presented. Finally, multi-component mixtures studied in the SCCO project are detailed.

2.
Bol. Asoc. Argent. Odontol. Niños ; 44(1): 3-7, abr.-ago. 2015. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-776094

RESUMO

Los traumatismos dentarios constituyen uno de los motivos más frecuentes en la consulta odontopediátrica. Si bien las fracturas radiculares en dentición primaria son las lesiones traumáticas menos prevalentes (2-4 por ciento), son de difícil resolución y ocasionan la pérdida de dichas piezas en la mayoría de los casos. Objetivo: describir la resolución del traumatismo con fractura radicular en ambos incisivos centrales superiores primarios. Diagnóstico de la situación inicial: paciente masculino de 4 años que acude con su madre a la Cátedra de Odontología Integral Niños de la FOUBA presentando un traumatismo dental de 2 horas de evolución. Diagnóstico clínico-radiográfico: fractura radicular horizontal de tercio medio del 5.1 y 6.1 (sin reabsorción fisiológica radicular), sin desplazamiento del fragmento coronario, con laceración de labio superior y encía marginal. Secuencia de procedimientos operatorios: historia clínica con consentimiento informado; anamnesis médica y odontológica; examen clínico y radiográfico de 5.1 y 6.1 y antagonistas; limpieza de tejidos blandos con clorhexidina; impresión con alginato; confección de placa posicionadora para ferulización; prueba e instalación de la placa; indicaciones al paciente y a su madre: uso permanente durante 45 días y uso nocturno, para comer y hacer deportes 45 días más. Recomendaciones de higiene; controles inmediatos: 30 y 45 días y 3 y 6 meses. Resolución del caso: en todos los controles, ambas piezas se presentaron asintomáticas. A los 6 meses se observa la correcta cicatrización radicular y la presencia de vitalidad en ambos incisivos. Conclusiones: el tratamiento temprano y los controles posteriores son fundamentales para preservar la salud pulpar y conseguir la reparación de los tejidos duros afectados.


Assuntos
Humanos , Masculino , Pré-Escolar , Dente Decíduo/lesões , Fraturas dos Dentes/terapia , Planejamento de Assistência ao Paciente , Raiz Dentária/lesões , Argentina , Assistência Odontológica para Crianças/métodos , Cicatrização/fisiologia , Faculdades de Odontologia , Seguimentos , Fraturas dos Dentes/diagnóstico , Incisivo/lesões , Incisivo , Placas Oclusais
3.
Actas urol. esp ; 37(5): 266-272, mayo 2013. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-112631

RESUMO

Introducción: El tratamiento estándar de las azoospermias es la recuperación espermática del testículo para inyección intracitoplásmica. El objetivo de este estudio es identificar factores predictivos de recuperación espermática. Material y métodos: Intentamos recuperar espermatozoides mediante extracción espermática del testículo (TESE) en 74 pacientes azoospérmicos. Se estudiaron los niveles séricos de FSH einhibina B (INHB), la histología testicular, la genética, la criptozoospermia y el tamaño testicular. Resultados: La recuperación espermática fue del 47,2% para el total de pacientes, del 36% para las azoospermias no obstructivas y del 100% para las obstructivas. La INHB baja y la FSH alta se correlacionaron con el fracaso en la recuperación espermática. Los puntos de corte obtenidos mediante curvas ROC fueron de 67 pg/ml para la INHB y de 12,2 mUI/ml para la FSH. En ningún paciente con microdeleción Y en AZF a, b se recuperaron espermatozoides. En el 100% de los pacientes con mutaciones CFTR se obtuvieron espermatozoides. La mayor tasa de recuperación espermática fue para las hipoespermatogénesis, seguidas de los bloqueos madurativos y de los solo Sertoli. En todos los pacientes con criptozoospermia se recuperaron espermatozoides. Se encontró una relación entre el tamaño testicular y la recuperación espermática, pero no resultó estadísticamente significativa. Conclusiones: Salvo las microdeleciones en AZF a, b ningún factor predictor descarta a un paciente para TESE. La INHB baja se relaciona mejor que la FSH alta con el fracaso en la recuperación espermática. La recuperación es posible en todos los casos de mutaciones CFTR. La ausencia de células germinales se correlaciona con una alta probabilidad de fracaso en la recuperación espermática. La presencia de criptozoospermia se vincula a una alta probabilidad de éxito en la recuperación espermática (AU)


Introduction: Testicular sperm extraction with intracytoplasmic sperm injection is the standard treatment for azoospermia. The objective of this study is to identify predictive factors of successful sperm retrieval. Materials and methods: Between June 2003 and May 2011, we tried testicular sperm extraction(TESE) in 74 azoospermic patients in the Reproductive Medicine Unit of Son Espases Hospital (Palma de Mallorca). Serum follicle stimulating hormone (FSH) and inhibin B levels, testicular histology, genetic study, presence or not of cryptozoospermia and testicular volume were examined. Results: Spermatozoa were successfully recovered in 47.2% of the total patients, in 36% of nonobstructiveazoospermic patients and in 100% of obstructive azoospermic patients. Low inhibin B and high FSH were correlated to sperm retrieval failure. The cutoff points were determined using ROC curves that were 67 pg/mL for inhibin B and 12.2 mUI/mL for FSH. Spermatozoa were not successfully retrieved in any patient with Y microdeletions in AZF a, b regions. Spermatozoa were successfully retrieved in 100% of the patients with CFTR mutations. The highest spermretrieval rate was for hypospermatogenesis, followed by maturation arrest and Sertoli-cellonly. Spermatozoa were successfully retrieved in all cryptozoospermic patients. Although usinga non-significant test, there seems to be a correlation between higher testicular volume and a higher probability of successful sperm retrieval. Conclusions: Except for Y microdeletions in AZF a, b regions, there is no predictive factor of testicular sperm retrieval to rule out a patient for TESE. Lower inhibin B is more related to spermretrieval failure than higher FSH. Sperm retrieval is possible for all cases of CFTR mutations but in any case of microdeletion Y in AZF a ,b. The lack of germ cells is correlated with a high probability of sperm retrieval failure. The presence of cryptozoospermia is correlated with a high probability of sperm retrieval success. We do not find a statistically significant relation between testicular volume and successful sperm retrieval (AU)


Assuntos
Humanos , Masculino , Azoospermia , Sêmen , Hormônio Foliculoestimulante , Espermatozoides , Recuperação Espermática , Subunidades beta de Inibinas , Bloqueadores de Espermatogênese/isolamento & purificação
4.
Actas Urol Esp ; 37(5): 266-72, 2013 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23062736

RESUMO

INTRODUCTION: Testicular sperm extraction with intracytoplasmic sperm injection is the standard treatment for azoospermia. The objective of this study is to identify predictive factors of successful sperm retrieval. MATERIALS AND METHODS: Between June 2003 and May 2011, we tried testicular sperm extraction (TESE) in 74 azoospermic patients in the Reproductive Medicine Unit of Son Espases Hospital (Palma de Mallorca). Serum follicle stimulating hormone (FSH) and inhibin B levels, testicular histology, genetic study, presence or not of cryptozoospermia and testicular volume were examined. RESULTS: Spermatozoa were successfully recovered in 47.2% of the total patients, in 36% of non-obstructive azoospermic patients and in 100% of obstructive azoospermic patients. Low inhibin B and high FSH were correlated to sperm retrieval failure. The cutoff points were determined using ROC curves that were 67 pg/mL for inhibin B and 12.2 mUI/mL for FSH. Spermatozoa were not successfully retrieved in any patient with Y microdeletions in AZFa,b regions. Spermatozoa were successfully retrieved in 100% of the patients with CFTR mutations. The highest sperm retrieval rate was for hypospermatogenesis, followed by maturation arrest and Sertoli-cell-only. Spermatozoa were successfully retrieved in all cryptozoospermic patients. Although using a non-significant test, there seems to be a correlation between higher testicular volume and a higher probability of successful sperm retrieval. CONCLUSIONS: Except for Y microdeletions in AZFa,b regions, there is no predictive factor of testicular sperm retrieval to rule out a patient for TESE. Lower inhibin B is more related to sperm retrieval failure than higher FSH. Sperm retrieval is possible for all cases of CFTR mutations but in any case of microdeletion Y in AZFa,b. The lack of germ cells is correlated with a high probability of sperm retrieval failure. The presence of cryptozoospermia is correlated with a high probability of sperm retrieval success. We do not find a statistically significant relation between testicular volume and successful sperm retrieval.


Assuntos
Azoospermia/patologia , Injeções de Esperma Intracitoplásmicas , Espermatozoides , Adulto , Azoospermia/sangue , Centrifugação , Deleção Cromossômica , Cromossomos Humanos Y/ultraestrutura , Regulador de Condutância Transmembrana em Fibrose Cística/deficiência , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Hormônio Foliculoestimulante/sangue , Humanos , Inibinas/sangue , Cariotipagem , Masculino , Tamanho do Órgão , Análise do Sêmen , Aberrações dos Cromossomos Sexuais , Manejo de Espécimes , Contagem de Espermatozoides , Maturação do Esperma , Espermatogênese , Testículo/patologia
5.
Environ Pollut ; 158(3): 704-10, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19892448

RESUMO

Blood biomarkers and levels of major pollutants in eggs and feathers were used to determine pollution effects in nestlings of the Purple Heron Ardea purpurea and the Little Egret Egretta garzetta, sampled on three Ebro River (NE Spain) areas: a reference site, a site affected by the effluents of a chlor-alkali industry and the river Delta. The two impacted heron populations showed mutually different pollutant and response patterns, suggesting different sources of contamination. In the population nesting near the chlor-alkali plant, elevated levels of hexachlorobenzene (HCB) and polychlorobiphenyls (PCBs) in eggs, and mercury in feathers in A. purpurea chicks were related with reduced blood antioxidant defenses and increased levels of micronuclei. In Ebro Delta, high levels of plasmatic lactate dehydrogenase in A. purpurea chicks and high frequency of micronuclei in blood of both species were tentatively associated with intensive agricultural activities taking place in the area. These results provide the first evidence of a biological response in heron chicks to the release of pollutants at a chlor-alkali plant.


Assuntos
Biomarcadores/sangue , Aves/fisiologia , Ovos/análise , Poluentes Ambientais/análise , Plumas/química , Animais , Aves/sangue , Poluentes Ambientais/sangue , Poluentes Ambientais/farmacologia , Feminino , Masculino , Mercúrio/análise , Testes para Micronúcleos , Comportamento de Nidação/efeitos dos fármacos , Bifenilos Policlorados/análise , Espanha
7.
Ann N Y Acad Sci ; 1077: 96-114, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17124117

RESUMO

The impact of short impulsive forces on the semiconductor segregation patterns inside a generic mug Bridgman growth arrangement is discussed here with the help of a time-dependent 2D numerical scheme. Impulses have been applied parallel to the growth interface, equivalently, orthogonal to the external thermal gradient. The present results indicate that for each one of the three semiconductors considered, the reduced longitudinal and radial solid segregation are practically insensitive to the pulse shape, rectangular or half-sinusoidal. The reduced longitudinal segregation only depends on the growth velocity for constant g-dose impulses. The reduced radial segregation depends on both the interface growth velocity and very weakly on the activity time of the constant g-dose impulse externally applied. The thermal flux across the interface is shape-dependent and does not act synchronically with half-sinusoidal external impulses. Also, as before, this flux depends on the activity time and on the growth velocity for constant g-dose impulses.

8.
Environ Geochem Health ; 26(2-3): 259-68, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15499782

RESUMO

The levels of organochlorine compounds in eggs of water birds from the colony on Tai Lake in China were studied. The eggs were collected in 2000 and belonged to the following species: 65 samples of black-crowned night heron (Nycticorax nycticorax), 36 samples of little egret (Egretta garzetta), 26 samples of cattle egret (Bubulcus ibis) from 13 clutches and 43 samples of Chinese pond heron (Ardeola bacchus) from 17 clutches. Dichlorodiphenyltrichloroethane (DDT) and its derivates (DDE and DDD), hexachlorocyclohexane (HCH) and its isomers (alpha-HCH, beta-HCH, gamma-HCH, delta-HCH), heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, endrin aldehyde, alpha-endosulfan, beta-endosulfan, and endosulfan sulfate were determined in the laboratory by gas chromatography. The data showed that DDE had the highest levels in all the samples, followed by beta-HCH. The mean levels of DDE among the water bird species were in the order as follows: black-crowned night heron (5464.26 ng/g, dry weight) > Chinese pond heron (2791.12 ng/g, dry weight) > little egret (1979.97 ng/g, dry weight) > cattle egret (660.11 ng/g, dry weight). DDT and its metabolites accounted for 90% of the total organochlorines, except that it was only 73% for cattle egret. The differences of the residue among the bird species were statistically significant and could be attributed to their variations in prey and habitat. Although the DDE burdens in Tai Lake were much lower than 8 microg/g (wet weight) which are thought to have significant adverse effects on black-crowned night herons, they would be expected to increase the risk of adverse effects on survival of chicks of herons and egrets, particularly black-crowned night heron, based on the critical value of 1 microg/g (wet weight) DDE. The burdens of HCHs in this study were higher and the cyclodienes were lower than those found elsewhere.


Assuntos
Aves , Inseticidas/análise , Resíduos de Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Animais Recém-Nascidos , China , Meio Ambiente , Monitoramento Ambiental , Feminino , Óvulo/química , Fatores de Risco , Análise de Sobrevida
9.
Chemosphere ; 55(4): 567-76, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15006509

RESUMO

The concentrations of PCBs, DDTs, HCHs, HCB and OCS were determined in sediments and associated biota, both invertebrates (Physella acuta, Hirudo medicinalis, chironomid larvae, Hydrous pistaceus, Helochares lividus) and vertebrates (Rana perezi), in a temporary aquatic system, a rice field in the Ebro Delta (NE Spain). The qualitative and quantitative distribution of organochlorine compounds in sediments and aquatic biota has been explained by two mechanisms: equilibrium partitioning and/or biomagnification through the trophic web. Nevertheless, bioaccumulation processes are by far more complex, since several biotic and abiotic factors contribute to the observed pollutant loads in the organisms. In this respect, the biological characteristics of the organisms considered (e.g. species, age, lipid contents, feeding habits, etc.), as well as ecological factors (e.g. the habitat of the species and vertical distribution), have been shown to account for the organochlorine levels observed.


Assuntos
Ecossistema , Poluentes Ambientais/análise , Sedimentos Geológicos/análise , Hidrocarbonetos Clorados , Inseticidas/análise , Invertebrados/química , Ranidae/metabolismo , Agricultura , Animais , Cromatografia Gasosa , Poluentes Ambientais/farmacocinética , Cadeia Alimentar , Inseticidas/farmacocinética , Oryza , Espanha , Especificidade da Espécie
10.
Arch Environ Contam Toxicol ; 45(3): 399-406, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14674593

RESUMO

Environments in Pakistan are subject to increasing pollution, but previous studies were very scanty. During 1999 and 2000, we assessed trace element contamination at three wetlands, Karachi Harbour (with presumed industrial-urban pollution), Taunsa Barrage (agricultural pollution), and Haleji Lake (relatively unpolluted), using as indicators the eggs and the feathers of colonial waterbirds, particularly Little Egrets, their prey, and the sediments collected within their foraging areas. The concentrations of As, Cd, Cr, Pb, Hg, Mn, Se, and Zn were generally within the normal background level, and mostly below the threshold that may affect bird survival or reproduction. However, somewhat high concentrations were found in fish from Karachi, for Pb that was at levels that may harm fish reproduction, and for Hg that was at limit concentration for human consumption. Alarming concentrations were found for Cr and Se in sediments from Karachi, that were above the critical levels for contaminated soil, and Se in eggs, that may affect egret reproduction. The differences among the three wetlands were less marked than hypothesized. The egret species within the same area differed in the concentration of certain elements in their eggs, possibly because females may have foraged in different habitats before breeding, whereas no interspecies difference was found in chick feathers, presumably because their food had been collected in similar habitats around the colony. High bioaccumulation from sediments to organic samples occurred for Hg, while Cd, Se, and Zn exhibited low accumulation; for all these elements, feathers of predatory birds such as the egrets are the best indicators of environmental contamination. On the other hand, As and Cr did not bioaccumulate, and the sediments, or the organisms low in the food chain, like fish or crustaceans, are better indicators of their presence in the environment than predatory birds.


Assuntos
Aves , Exposição Ambiental , Monitoramento Ambiental/métodos , Poluentes Ambientais/farmacocinética , Metais Pesados/farmacocinética , Animais , Plumas/química , Feminino , Masculino , Óvulo/química , Paquistão , Distribuição Tecidual
11.
Arch Environ Contam Toxicol ; 44(3): 360-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12712296

RESUMO

The main goal of the present work has been to study the use of egret eggs to assess environmental pollution by POPs (HCB, HCHs, cyclodienes, DDTs and PCBs) in three Pakistani wetlands that are presumed to be affected by different types of pollution. Taunsa Barrage, affected mainly by agricultural pollutants; Karachi Harbor because of the supposed exposure to industrial activity-related POPs; and Haleji Lake as a relatively pristine area because of its location in a stony desert. Taunsa Barrage and Haleji Lake are wetlands of international importance according to the Ramsar Convention, while the Karachi Harbor is of interest because of the large human population living there. Eggs of the white ( Egretta garzetta garzetta) and dark ( Egretta garzetta gularis) morphs of Little Egrets were used as monitoring tools. Concentrations were also determined in several prey in this species' diet and in the sediments collected in their foraging areas. Differences in egg pollutant content among the three localities were significant for all the compounds. Overall, the eggs from Haleji Lake and Karachi showed, respectively, the lowest and highest percentages of detection and organochlorine concentrations. Biomagnification from sediments to prey and then to eggs has been documented in the three areas studied and is accompanied by higher percentages of detection of different compounds through the compartments. Differences in the biomagnification factor among the areas were small, even when differences in pollutant concentrations were high, suggesting that eggs are reliable indicators of POPs in the environment. The values found were generally lower than those reported for the eggs of large herons from North America or the Mediterranean basin, and are about the same order of magnitude that those of other medium-sized egrets from other parts of the world.


Assuntos
Aves/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Óvulo/química , Animais , Paquistão
14.
Arch Environ Contam Toxicol ; 39(1): 119-23, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10790510

RESUMO

We determined mercury and selenium in 43 eggs (eggshell, albumen, and yolk) which belong to different clutch sizes of Audouin's gull from the Chafarinas Islands. The results were compared with those obtained previously with the same species at the Ebro Delta. Both, the intra- and the interclutch sources of variability have been examined. There is an effect of the female on mercury and selenium concentrations in a clutch, which supports the use of eggs as monitoring tools. The distribution pattern of mercury among albumen, yolk and eggshell, the dynamics of this element during the laying process, as well as data concerning egg formation strategies suggest that the mercury in the albumen corresponds mainly to the mercury acquired by the female while feeding in the breeding area. The mercury and selenium levels of the eggs from the Chafarinas Islands were lower than those of the Ebro Delta, which can be due to differences in both the marine contamination and the diet in the two colonies.


Assuntos
Aves/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Animais , Ovos/análise , Feminino , Região do Mediterrâneo , Mercúrio/análise , Selênio/análise
17.
Chemosphere ; 31(6): 3397-411, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8528648

RESUMO

Polychlorinated biphenyls, dibenzodioxins and dibenzofurans were analysed in eggs of a protected gull species, the Audouin's Gull (Larus audouinii) and compared to those of the Yellow-legged Gull (Larus cachinnans), both breeding in the Western Mediterranean (Ebro Delta and Medes Islands, respectively). Differences in concentrations as well as in congener profiles reflected differences in both habitat and diet of the two species. Levels of AHH-active PCB congeners were lower in Yellow-legged Gull (0.4-1.6 micrograms/g d.w) than in Audouin's Gull eggs (1.2-33.9 micrograms/g d.w.). These concentrations, expressed in international toxic equivalence factors (i-TEQ/g d.w.), were on average 24 times higher in the Audouin's gull. I-TEQ levels due to dioxins were also higher in this species by a factor of ca. 7. I-TEQ levels related to PCBs resulted 90-230 times higher than those of dioxins and furans. Thus, AHH-inducing PCBs might represent even higher toxicological hazards than dioxins and furans to some populations of seabirds. The necessity of assessing the impact of these compounds in rare and protected species is pointed out.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Dioxinas/análise , Furanos/análise , Óvulo/química , Bifenilos Policlorados/análise , Animais , Aves , Dioxinas/toxicidade , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Furanos/toxicidade , Ilhas do Mediterrâneo , Óvulo/efeitos dos fármacos , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidade , Reprodução/efeitos dos fármacos
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