Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
1.
Development ; 151(16)2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39037017

RESUMEN

Following up on our previous observation that early B cell factor (EBF) sites are enriched in open chromatin of the developing sensory epithelium of the mouse cochlea, we investigated the effect of deletion of Ebf1 on inner ear development. We used a Cre driver to delete Ebf1 at the otocyst stage before development of the cochlea. We examined the cochlea at postnatal day (P) 1 and found that the sensory epithelium had doubled in size but the length of the cochlear duct was unaffected. We also found that deletion of Ebf1 led to ectopic sensory patches in the Kölliker's organ. Innervation of the developing organ of Corti was disrupted with no obvious spiral bundles. The ectopic patches were also innervated. All the extra hair cells (HCs) within the sensory epithelium and Kölliker's organ contained mechanoelectrical transduction channels, as indicated by rapid uptake of FM1-43. The excessive numbers of HCs were still present in the adult Ebf1 conditional knockout (cKO) animal. The animals had significantly elevated auditory brainstem response thresholds, suggesting that this gene is essential for hearing development.


Asunto(s)
Células Ciliadas Auditivas , Ratones Noqueados , Órgano Espiral , Transactivadores , Animales , Transactivadores/genética , Transactivadores/metabolismo , Órgano Espiral/metabolismo , Células Ciliadas Auditivas/metabolismo , Ratones , Sordera/genética , Eliminación de Gen , Células Laberínticas de Soporte/metabolismo , Cóclea/metabolismo , Potenciales Evocados Auditivos del Tronco Encefálico
2.
An Acad Bras Cienc ; 91(4): e20190302, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31664309

RESUMEN

The beautifully colored damselflies included in Neoneura Selys are divided in 28 species known from North, Central and South America. Larval stage is little known, only seven species were described at this stage. We describe and illustrate the final instar larva of Neoneura confundens for the first time. Adults associated to this larva correspond to the blue form of the species and are also discussed and illustrated. The larva of N. confundens is similar to other Neoneura larvae, showing 1 premental seta and a well-marked nodus in caudal lamellae, but it can be differentiated by having fringed posterior margin in all tibiae and in middle and hind tarsi, among other characters. A key to known larvae of Neoneura and new records extending the species range in the southern cone are provided.


Asunto(s)
Larva/anatomía & histología , Odonata/anatomía & histología , Animales , Tamaño Corporal , Femenino , Larva/clasificación , Masculino , Odonata/clasificación , América del Sur , Tibia
3.
J Biochem ; 149(2): 211-7, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21113053

RESUMEN

Mercurials are known to induce morphological and functional modifications in kidney. The protective effect of octylguanidine on the injury induced by Hg(2+) on renal functions was studied. Octylguanidine administered at a dose of 10 mg/kg body weight prevented the damage induced by Hg(2+) administration at a dose of 3 mg/kg body weight. The findings indicate that octylguanidine spared mitochondria from Hg(2+)-poisoning by preserving their ability to retain matrix content, such as accumulated Ca(2+) and pyridine nucleotides. The hydrophobic amine also protected mitochondria from the Hg(2+)-induced loss of the transmembrane potential, and from the oxidative injury of mitochondrial DNA. In addition, octylguanidine maintained renal functions, such as normal values of creatinine clearance and blood urea nitrogen (BUN), and serum creatinine after Hg(2+) administration. It is proposed that octylguanidine protects kidney by inhibiting Hg(2+) uptake to kidney tissue, and in consequence its binding to mitochondrial membrane through a screening phenomenon, in addition to its known action as inhibitor of permeability transition.


Asunto(s)
Guanidinas/administración & dosificación , Riñón/efectos de los fármacos , Intoxicación por Mercurio/tratamiento farmacológico , Mercurio/toxicidad , Animales , Nitrógeno de la Urea Sanguínea , Calcio/metabolismo , Permeabilidad de la Membrana Celular/efectos de los fármacos , Creatinina/sangre , Guanidinas/uso terapéutico , Riñón/lesiones , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Intoxicación por Mercurio/prevención & control , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Membranas Mitocondriales/efectos de los fármacos , Membranas Mitocondriales/metabolismo , Nucleótidos/metabolismo , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar
4.
Cell Biol Int ; 29(7): 551-8, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15979905

RESUMEN

The purpose of this work was to assess the effect of oligomycin on the mitochondrial membrane permeability transition. The antibiotic was found to strengthen cyclosporin A (CSA)-induced protection of non-specific permeability, which is triggered by a matrix Ca2+ load in the absence of ADP. Oligomycin also reinforced the protective effect of CSA on carboxyatractyloside-induced pore opening in the absence of ADP, but failed to do so in mitochondria incubated under anaerobic conditions or after addition of CCCP. Analyzing the efflux of matrix Ca2+, we found that mitochondrial swelling and the collapse of the transmembrane electric gradient coincided with membrane leakage. The effects of the antibiotic were observed in phosphate-containing media but not in the presence of acetate. Furthermore, N-ethylmaleimide hindered the protective effect of oligomycin-CSA. In addition, the matrix phosphate concentration increased concurrently with a diminution in the matrix-free fraction of Ca2+. We concluded that oligomycin increases phosphate uptake by stimulating the phosphate-/OH- exchange reaction.


Asunto(s)
Ciclosporina/farmacología , Riñón/metabolismo , Mitocondrias/metabolismo , Oligomicinas/farmacología , Acetatos/metabolismo , Animales , Atractilósido/análogos & derivados , Atractilósido/farmacología , Calcio/metabolismo , Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Etilmaleimida/farmacología , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/metabolismo , Riñón/fisiología , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Dilatación Mitocondrial/efectos de los fármacos , Permeabilidad/efectos de los fármacos , Fosfatos/metabolismo , Ratas , Desacopladores/farmacología
5.
Rio de Janeiro; Instituto de Pesquisa Economica Aplicada; 1993. 544 p. ilus, tab.(IPEA, 139).
Monografía en Portugués | LILACS | ID: lil-159784

RESUMEN

Investiga a situaçäo social brasileira e sua evoluçäo recente. Contribui para a formulaçäo de estratégia de transformaçäo social com crescimento econômico sustentado e com modernizaçäo política. Empreende análise desagregada das diversas situaçöes que compöe o mosaico social brasileiro, bem como de sua evoluçäo, através de um conjunto de indicadores agregados em índices de desenvolvimento relativo e do nível de vida. Identifica as características distintas dos processos sociais das duas últimas décadas e analisa as principais implicaçöes político-estratégicas. Examina as desigualdades de renda, educaçäo básica, a pobreza absoluta, as condiçöes habitacionais, e a evoluçäo demográfica. Formula as sugestöes de política e de estratégia julgadas pertinentes. Identifica os padröes de desempenho e as relaçöes estruturais do desenvolvimento brasileiro e analisa as correspondências e assimetrias entre as suas dimensöes econômica, social e política. Propöe uma concepçäo de estratégia social consistente com a opçäo pós-liberal e examina alguns de seus desdobramentos


Asunto(s)
Humanos , Masculino , Femenino , Desarrollo Económico , Política Pública , Brasil , Condiciones Sociales/economía , Demografía , Educación/economía , Ambiente , Vivienda/economía , Renta , Pobreza/economía , Cambio Social , Factores Socioeconómicos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA