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Sample records for capacidad contractil uterina

  1. EFECTO IN VITRO DE LA INSULINA SOBRE LA CAPACIDAD CONTRACTIL UTERINA INDUCIDA POR OXITOCINA

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    Figueroa D.,Horacio; Marusic B.,Elisa T.; González N.,Magdalena; Barcos M.,Francisca; Yungue V.,Paola

    2002-01-01

    La capacidad contráctil del útero puede ser evaluada in vitro por medio del método isométrico. El objetivo de este estudio fue comparar la efectividad de la administración simultánea de oxitocina e insulina en la contractilidad uterina. La comparación entre ambas hormonas se realizó en úteros aislados de dos modelos experimentales: ratas hembras adultas en diferentes fases del ciclo estral y ratas preñadas en fase final de preñez. Los úteros de estos animales fueron sometidos, in vitro, a la ...

  2. Intussuscepção uterina em uma cadela Yorkshire Terrier

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    Pinto Filho, S.T.L.; Carus, D.S.; Dalmolin, F.; Anjos, B.L.; Segatto, T.; Krabbe, A.; Oliveira, M.T.; Pippi, N.L.; Brun, M.V.

    2015-01-01

    A intussuscepção uterina é condição rara em pequenos animais. No presente relato descreve-se um caso de intussuscepção uterina em um canino, fêmea Yorkshire Terrier no pós-parto imediato, diagnosticada por meio de laparotomia exploratória e pela avaliação anatomopatológica. Realizou-se a ovariossalpingo-histerectomia (OSH) como tratamento definitivo para a alteração. Conclui-se, portanto, que a intussuscepção uterina pode ocorrer em cadelas, de forma espontânea no pós-parto imediato. Uteri...

  3. Patología uterina y su impacto en la fertilidad

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    V. Jaime Albornoz, Dr.; A. Gonzalo Duque, Dr.

    2010-01-01

    El útero es un órgano fundamental dentro del proceso reproductivo y participa en eventos claves, como el transporte espermático, la implantación y la nutrición fetal. Los miomas uterinos, las anomalías congénitas, los pólipos endometriales y las sinequias uterinas son las principales patologías uterinas en mujeres en edad reproductiva, y pueden ser causa de infertilidad, aborto recurrente o parto prematuro. De acuerdo a la evidencia, el tratamiento quirúrgico de miomas uterinos submucosos e i...

  4. Symphysis-fundal height curve in the diagnosis of fetal growth deviations Curva de altura uterina por edad de gestación y diagnóstico de desvíos del crecimiento fetal Curva de altura uterina por idade gestacional e diagnóstico de desvios do crescimento fetal

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    Djacyr Magna Cabral Freire

    2010-12-01

    marzo y octubre de 2006, con edad de gestación por encima de 27 semanas. La altura uterina fue medida de acuerdo con técnica recomendada por el Ministerio de la Salud. El patrón-oro fue el peso fetal, estimado por el ultrasonido con base en la curva de referencia brasilera por edad de gestación. Una sub-muestra de 122 casos con pesos neonatales obtenidos hasta siete días después de la estimación del peso fetal, la clasificación de la altura uterina fue comparada con la curva de Lubchenco como estándar-oro. La sensibilidad, la especificidad y los valores predictivos positivo y negativo fueron calculados. Para comparar el desempeño de la sensibilidad entre ambas curvas de altura uterina, se utilizó la prueba chi-cuadrado de McNemar. RESULTADOS: La sensibilidad de la nueva curva para la detección de fetos pequeños para la edad de gestación fue de 51,6%, mientras que la curva del patrón-oro fue significativamente menor (12,5%. En la sub-muestra que tuvo el peso neonatal como estándar-oro, la sensibilidad de la nueva curva de referencia fue de 87,7%, mientras que la del Ministerio de la Salud exhibió 42,9% de sensibilidad para la detección de fetos pequeños para la edad de gestación. CONCLUSIONES: La capacidad diagnóstica de la nueva curva de referencia para detectar fetos pequeños para la edad de gestación fue significativamente mejor que la curva recomendada por el Ministerio de la Salud.OBJETIVO: Validar curva de referência de altura uterina por idade gestacional para o rastreamento de desvios do crescimento fetal e comparar sua performance com a curva-padrão adotada pelo Ministério da Saúde do Brasil. MÉTODOS: Estudo observacional que envolveu 753 gestantes de baixo risco de João Pessoa, PB, entre março e outubro de 2006, com idade gestacional acima de 27 semanas. A altura uterina foi medida de acordo com técnica preconizada pelo Ministério da Saúde. O padrão-ouro foi o peso fetal, estimado pelo ultrassom com base na curva de refer

  5. Fractalkine depresses cardiomyocyte contractility.

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    David Taube

    Full Text Available Our laboratory reported that male mice with cardiomyocyte-selective knockout of the prostaglandin E2 EP4 receptor sub-type (EP4 KO exhibit reduced cardiac function. Gene array on left ventricles (LV showed increased fractalkine, a chemokine implicated in heart failure. We therefore hypothesized that fractalkine is regulated by PGE2 and contributes to depressed contractility via alterations in intracellular calcium.Fractalkine was measured in LV of 28-32 week old male EP4 KO and wild type controls (WT by ELISA and the effect of PGE2 on fractalkine secretion was measured in cultured neonatal cardiomyocytes and fibroblasts. The effect of fractalkine on contractility and intracellular calcium was determined in Fura-2 AM-loaded, electrical field-paced cardiomyocytes. Cardiomyocytes (AVM from male C57Bl/6 mice were treated with fractalkine and responses measured under basal conditions and after isoproterenol (Iso stimulation.LV fractalkine was increased in EP4 KO mice but surprisingly, PGE2 regulated fractalkine secretion only in fibroblasts. Fractalkine treatment of AVM decreased both the speed of contraction and relaxation under basal conditions and after Iso stimulation. Despite reducing contractility after Iso stimulation, fractalkine increased the Ca(2+ transient amplitude but decreased phosphorylation of cardiac troponin I, suggesting direct effects on the contractile machinery.Fractalkine depresses myocyte contractility by mechanisms downstream of intracellular calcium.

  6. Efeitos da doença uterina na eficiência reprodutiva de bovinos leiteiros

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    Pires, Maria João de Almeida

    2018-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária O período do pós-parto é um período de grande importância na vida reprodutiva de uma vaca leiteira, em que é bastante comum o desenvolvimento de doença uterina. A função uterina no pós-parto está frequentemente comprometida devido à contaminação bacteriana presente neste período, e pela persistência de microrganismos no lúmen uterino, causando assim doença e consequentemente infertilidade. Esta doença está associada a taxas de conce...

  7. Patología uterina y su impacto en la fertilidad

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    V. Jaime Albornoz, Dr.

    2010-05-01

    Full Text Available El útero es un órgano fundamental dentro del proceso reproductivo y participa en eventos claves, como el transporte espermático, la implantación y la nutrición fetal. Los miomas uterinos, las anomalías congénitas, los pólipos endometriales y las sinequias uterinas son las principales patologías uterinas en mujeres en edad reproductiva, y pueden ser causa de infertilidad, aborto recurrente o parto prematuro. De acuerdo a la evidencia, el tratamiento quirúrgico de miomas uterinos submucosos e intramurales (que distorsionan la cavidad uterina, pólipos endometriales y sinequias se asocia a un aumento significativo en las tasas de embarazo. El tratamiento quirúrgico del septum uterino disminuye significativamente la probabilidad de aborto a repetición y puede incrementar la probabilidad de embarazo en pacientes sin otra causa aparente de infertilidad. El tratamiento quirúrgico de miomas intramurales y subserosos (que no comprometen la cavidad endometrial es controvertido y su indicación depende de la evaluación de cada caso en particular.

  8. La sutura compresiva del útero en cesárea con atonía uterina

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    Percy Pacora

    2004-12-01

    Full Text Available Objetivo: Determinar si el empleo de la sutura compresiva del útero (técnica de B-Lynch durante la cesárea en casos de atonía uterina disminuye la pérdida sanguínea y evita la histerectomía posparto. Material y Métodos: Estudio retrospectivo de las cesáreas que cursaron con atonía uterina durante la intervención, desde el 1 de enero de 1990 al 31 de diciembre de 2003, en el Hospital San Bartolomé de Lima. El método estándar de manejo de la atonía uterina en la cesárea consiste en el masaje uterino, el empleo de agentes uterotónicos (ocitocina, prostaglandinas, ligadura de arterias uterinas/hipogástricas y la histerectomía posparto. Las variables maternas y perinatales obtenidas de las historias clínicas fueron ingresadas a una base de datos computarizado (SPSS versión 10. Resultados: Se identificó 46 casos: en 30 se empleó la técnica B-Lynch y en 16 el método estándar. No hubo diferencias en las características maternas entre ambos grupos. El grupo de B-Lynch presentó subjetivamente menor perdida sanguínea, recibió menor número de unidades de sangre transfundida y presentó significativo menor riesgo de histerectomía posparto comparado con el método estándar (promedio ± DE: 1144,4±311,7 mL vs 1666,9±794,4 mL, p<0,05; 0,36±0,66 vs 2,90±3,64, p<0,05; y OR 0,08, IC95% 0,01-0,45, p<0,01, respectivamente. Conclusiones: La sutura compresiva del útero durante la cesárea en la atonía uterina parece reducir el sangrado vaginal, la transfusión sanguínea y el empleo de la histerectomía comparado con el método estándar.

  9. Altas capacidades en el aula /

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    Conesa Muñoz., María Gregoria

    2014-01-01

    Las altas capacidades necesitan un tratamiento específico, del mismo modo que lo necesitan otros alumnos con dificultades para el aprendizaje, el hecho de que les sea más fácil aprender no significa que no se deban potenciar sus capacidades. Se analiza el tratamiento que han tenido las altas capacidades intelectuales a lo largo de los diferentes sistemas educativos, se ven las características más importantes que pueden tener estos niños y las diferentes vías de identificación y diagnóstico. ...

  10. Resposta inflamatória uterina em éguas submetidas a inseminação artificial

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    Carmona, Julieta Maria Peixoto

    2011-01-01

    Dissertação de Mestrado Integrado em Medicina Veterinária A inseminação artificial de éguas resulta invariavelmente numa resposta inflamatória uterina transitória e fisiológica cuja função é eliminar o excesso de espermatozóides, plasma seminal, diluidores e microrganismos do lúmen uterino. Esta inflamação é caracterizada por um influxo de polimorfonucleares neutrófilos (PMNs) para o lúmen uterino. A sua presença e magnitude pode ser diagnosticada através de ecografia uterina transrectal e...

  11. Estudo anatômico comparativo do útero e tubas uterinas de vacas e novilhas da raça Nelore (Bos primigenius indicus

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    Cristina Maria Rodrigues Monteiro

    2001-01-01

    Full Text Available Ao finalizarmos esta pesquisa, obtivemos dados anatômicos comparativos dos comprimentos dos cornos uterinos e tubas uterinas de vacas e novilhas da raça Nelore. Foram utilizadas para tais fins 45 amostras dos órgãos para cada grupo de animais. Os resultados mostraram que os comprimentos médios dos cornos uterinos e das tubas uterinas direitos e esquerdos das vacas não diferem estatisticamente entre si, sendo de 26,0 cm para os cornos uterinos direito e esquerdo, 17,6 cm para a tuba uterina direita e 17,7 cm para a esquerda. Os comprimentos médios dos cornos uterinos e das tubas uterinas direitos e esquerdos das novilhas não diferem estatisticamente entre si, apresentando 14,6 cm para o corno direito, 14,8 cm para o esquerdo, 15,4 cm para a tuba uterina direita e 15,2 cm para a esquerda. Há diferença estatisticamente significativa no comprimento médio dos cornos uterinos entre vacas e novilhas, com, respectivamente, 26,01 cm e 14,72 cm. Há diferença estatisticamente significativa no comprimento médio das tubas uterinas entre vacas e novilhas, com, respectivamente 17,64 cm e 15,29 cm. Nas vacas, o comprimento médio dos cornos uterinos, 26,01 cm, é maior que o comprimento médio das tubas uterinas, 17,64 cm. Nas novilhas, o comprimento médio dos cornos uterinos, 14,72 cm, é ligeiramente menor que o comprimento médio das tubas uterinas, 15,29 cm. Quando há aumento do comprimento médio dos cornos uterinos, há aumento concomitante das tubas uterinas em vacas, não acontecendo o mesmo em novilhas.

  12. Malformación arterio-venosa uterina y hemorragia obstétrica: diagnóstico y manejo en tres casos clínicos

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    Hasbun H, Jorge; Palavecino R, Patricio; Segura H, Patricia; Chavez R, Ignacio; Burgos S, Nelson; Tobar A, Hermógenes; Aliaga Q, Adolfo

    2014-01-01

    Las malformaciones vasculares uterinas son muy infrecuentes y se presentan asociadas a metrorragia con riesgo vital. Su incidencia no es conocida porque las series son de pocos casos. Presentamos tres pacientes con hemorragia obstétrica cuyo estudio diagnóstico con ultrasonido y angiografía, demostró malformación arteriovenosa uterina. En un caso, dada la extensión de la lesión, el tratamiento fue con embolización bilateral de arterias uterinas seguida de histerectomía. Otras dos pacientes, p...

  13. Structural comparison of contractile nanomachines

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    Sebastian Kube

    2015-05-01

    Full Text Available Contractile molecular machines are a common feature among bacteriophages and prokaryotes. Due to their stability and the large size, contractile-tailed bacteriophages are traditionally investigated by electron microscopic methods. Complemented by crystallographic studies, a molecular model of contraction for the T4 phage was developed. Lately, also related contractile structures like the Photorhabdus virulence cassette-like particles, the R-Type pyocins and the contractile tubule of the bacterial Type VI secretion system have been analyzed by cryo electron microscopy. Photorhabdus virulence cassette particles and R-Type pyocins are toxin complexes reminiscent of bacteriophage tails that are secreted by bacteria to kill their insect host or competing bacteria. In contrast, the Type VI secretion system is an intracellular apparatus for injection of effector proteins into bacterial and eukaryotic cells. Although it shares homology with other contractile systems, the Type VI secretion system is additionally equipped with a recycling function, which makes it suitable for multiple rounds of action. Starting from the 3D reconstructions, we compare these molecular machines structurally and functionally to their viral counterparts and summarize the current knowledge on their respective mode of action.

  14. Malformación arteriovenosa uterina: A propósito de un caso

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    Badía Agustí, Paloma; Tamarit Bordes, Silvia; Alcover Barrachina, Inmaculada; Tamarit Bordes, Gemma; Pérez-Moneo Pérez, Patricia; Reyes Balanzá Chancosa, María

    2016-01-01

    Paciente de 37 años que acudió a urgencias por metrorragia, G3P1A2, el último de ellos un aborto tardío en gestación gemelar monocorial biamniótica de 20 semanas hacía dos meses. En la ecografía destaca en zona miometrial un área de marcada vascularización de 67 x 45 mm. Tras descartar proceso residual gestacional y ante la sospecha de malformación arteriovenosa uterina se solicitó resonancia magnética nuclear y angiotac, tras confirmar la malformación vascular se programó para embolización d...

  15. Modulatory effects of taurine on jejunal contractility

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    Q.Y. Yao

    2014-12-01

    Full Text Available Taurine (2-aminoethanesulfonic acid is widely distributed in animal tissues and has diverse pharmacological effects. However, the role of taurine in modulating smooth muscle contractility is still controversial. We propose that taurine (5-80 mM can exert bidirectional modulation on the contractility of isolated rat jejunal segments. Different low and high contractile states were induced in isolated jejunal segments of rats to observe the effects of taurine and the associated mechanisms. Taurine induced stimulatory effects on the contractility of isolated rat jejunal segments at 3 different low contractile states, and inhibitory effects at 3 different high contractile states. Bidirectional modulation was not observed in the presence of verapamil or tetrodotoxin, suggesting that taurine-induced bidirectional modulation is Ca2+ dependent and requires the presence of the enteric nervous system. The stimulatory effects of taurine on the contractility of isolated jejunal segments was blocked by atropine but not by diphenhydramine or by cimetidine, suggesting that muscarinic-linked activation was involved in the stimulatory effects when isolated jejunal segments were in a low contractile state. The inhibitory effects of taurine on the contractility of isolated jejunal segments were blocked by propranolol and L-NG-nitroarginine but not by phentolamine, suggesting that adrenergic β receptors and a nitric oxide relaxing mechanism were involved when isolated jejunal segments were in high contractile states. No bidirectional effects of taurine on myosin phosphorylation were observed. The contractile states of jejunal segments determine taurine-induced stimulatory or inhibitory effects, which are associated with muscarinic receptors and adrenergic β receptors, and a nitric oxide associated relaxing mechanism.

  16. Modulatory effects of taurine on jejunal contractility

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    Yao, Q.Y.; Chen, D.P.; Ye, D.M.; Diao, Y.P.; Lin, Y. [Dalian Medical University, Dalian, Liaoning (China)

    2014-10-14

    Taurine (2-aminoethanesulfonic acid) is widely distributed in animal tissues and has diverse pharmacological effects. However, the role of taurine in modulating smooth muscle contractility is still controversial. We propose that taurine (5-80 mM) can exert bidirectional modulation on the contractility of isolated rat jejunal segments. Different low and high contractile states were induced in isolated jejunal segments of rats to observe the effects of taurine and the associated mechanisms. Taurine induced stimulatory effects on the contractility of isolated rat jejunal segments at 3 different low contractile states, and inhibitory effects at 3 different high contractile states. Bidirectional modulation was not observed in the presence of verapamil or tetrodotoxin, suggesting that taurine-induced bidirectional modulation is Ca{sup 2+} dependent and requires the presence of the enteric nervous system. The stimulatory effects of taurine on the contractility of isolated jejunal segments was blocked by atropine but not by diphenhydramine or by cimetidine, suggesting that muscarinic-linked activation was involved in the stimulatory effects when isolated jejunal segments were in a low contractile state. The inhibitory effects of taurine on the contractility of isolated jejunal segments were blocked by propranolol and L-NG-nitroarginine but not by phentolamine, suggesting that adrenergic β receptors and a nitric oxide relaxing mechanism were involved when isolated jejunal segments were in high contractile states. No bidirectional effects of taurine on myosin phosphorylation were observed. The contractile states of jejunal segments determine taurine-induced stimulatory or inhibitory effects, which are associated with muscarinic receptors and adrenergic β receptors, and a nitric oxide associated relaxing mechanism.

  17. Modulatory effects of taurine on jejunal contractility

    International Nuclear Information System (INIS)

    Yao, Q.Y.; Chen, D.P.; Ye, D.M.; Diao, Y.P.; Lin, Y.

    2014-01-01

    Taurine (2-aminoethanesulfonic acid) is widely distributed in animal tissues and has diverse pharmacological effects. However, the role of taurine in modulating smooth muscle contractility is still controversial. We propose that taurine (5-80 mM) can exert bidirectional modulation on the contractility of isolated rat jejunal segments. Different low and high contractile states were induced in isolated jejunal segments of rats to observe the effects of taurine and the associated mechanisms. Taurine induced stimulatory effects on the contractility of isolated rat jejunal segments at 3 different low contractile states, and inhibitory effects at 3 different high contractile states. Bidirectional modulation was not observed in the presence of verapamil or tetrodotoxin, suggesting that taurine-induced bidirectional modulation is Ca 2+ dependent and requires the presence of the enteric nervous system. The stimulatory effects of taurine on the contractility of isolated jejunal segments was blocked by atropine but not by diphenhydramine or by cimetidine, suggesting that muscarinic-linked activation was involved in the stimulatory effects when isolated jejunal segments were in a low contractile state. The inhibitory effects of taurine on the contractility of isolated jejunal segments were blocked by propranolol and L-NG-nitroarginine but not by phentolamine, suggesting that adrenergic β receptors and a nitric oxide relaxing mechanism were involved when isolated jejunal segments were in high contractile states. No bidirectional effects of taurine on myosin phosphorylation were observed. The contractile states of jejunal segments determine taurine-induced stimulatory or inhibitory effects, which are associated with muscarinic receptors and adrenergic β receptors, and a nitric oxide associated relaxing mechanism

  18. Modulatory effects of taurine on jejunal contractility

    Science.gov (United States)

    Yao, Q.Y.; Chen, D.P.; Ye, D.M.; Diao, Y.P.; Lin, Y.

    2014-01-01

    Taurine (2-aminoethanesulfonic acid) is widely distributed in animal tissues and has diverse pharmacological effects. However, the role of taurine in modulating smooth muscle contractility is still controversial. We propose that taurine (5-80 mM) can exert bidirectional modulation on the contractility of isolated rat jejunal segments. Different low and high contractile states were induced in isolated jejunal segments of rats to observe the effects of taurine and the associated mechanisms. Taurine induced stimulatory effects on the contractility of isolated rat jejunal segments at 3 different low contractile states, and inhibitory effects at 3 different high contractile states. Bidirectional modulation was not observed in the presence of verapamil or tetrodotoxin, suggesting that taurine-induced bidirectional modulation is Ca2+ dependent and requires the presence of the enteric nervous system. The stimulatory effects of taurine on the contractility of isolated jejunal segments was blocked by atropine but not by diphenhydramine or by cimetidine, suggesting that muscarinic-linked activation was involved in the stimulatory effects when isolated jejunal segments were in a low contractile state. The inhibitory effects of taurine on the contractility of isolated jejunal segments were blocked by propranolol and L-NG-nitroarginine but not by phentolamine, suggesting that adrenergic β receptors and a nitric oxide relaxing mechanism were involved when isolated jejunal segments were in high contractile states. No bidirectional effects of taurine on myosin phosphorylation were observed. The contractile states of jejunal segments determine taurine-induced stimulatory or inhibitory effects, which are associated with muscarinic receptors and adrenergic β receptors, and a nitric oxide associated relaxing mechanism. PMID:25387674

  19. Compensatory Hypertrophy of Skeletal Muscle: Contractile Characteristics

    Science.gov (United States)

    Ianuzzo, C. D.; Chen, V.

    1977-01-01

    Describes an experiment using rats that demonstrates contractile characteristics of normal and hypertrophied muscle. Compensatory hypertrophy of the plantaris muscle is induced by surgical removal of the synergistic gastrocnemium muscle. Includes methods for determination of contractile properties of normal and hypertrophied muscle and…

  20. CAPACIDAD TRANSACCIONAL: EVIDENCIAS DEL SISTEMA FINANCIERO PERUANO

    OpenAIRE

    TELLO-GAMARRA, JORGE; HERNANI-MERINO, MARTÍN; LÍMACO-MAMANI, BRYAN IVÁN

    2017-01-01

    RESUMEN Aunque existen algunos esfuerzos por integrar las perspectivas de capacidades y la economía de los costos de transacción, los avances en esa dirección son escasos. La integración de esas dos perspectivas es una emergente área de estudio llamada capacidad transaccional. Este artículo tiene por objetivo examinar la capacidad transaccional de firmas que operan en el sistema financiero peruano. El método escogido para la búsqueda de evidencias en ese sector es el estudio de casos múltiple...

  1. O modelo de pseudogestação em camundongos para o estudo 'in situ' das celulas Natural Killer uterinas

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    Juares Ednaldo Romero Bianco

    2006-01-01

    Resumo: Durante o período peri-implantacional na gestação de humanos e roedores, ocorre no estroma da mucosa uterina um conjunto de fenômenos que envolvem modificações dos componentes celulares e da matriz extracelular. Este conjunto de modificações é conhecido como decidualização ou reação decidual. Concomitante a este processo ocorre a migração de leucócitos provenientes de órgão hematopoéticos para este estroma. Dentre estes leucócitos predominam as subpopulações de linfócitos denominados ...

  2. LA CAPACIDAD ACELERATIVA EN EL DEPORTE

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    Isidoro Hornillos Baz

    2010-01-01

    La capacidad acelerativa adquiere una gran relevancia en las disciplinas deportivas que exigen desplazamientos rápidos. Forma parte de la velocidad, como cualidad motora, en su dimensión compleja. Desde una perspectiva bioenergética, la aceleración depende de la potencia del sistema anaeróbico aláctico. Para mejorar esta capacidad será necesario realizar ejercicios a la máxima intensidad, con recuperaciones completas y con una duración no superior a los seis segundos, en general. También desa...

  3. UTERINE PROLAPSE IN QUEEN AND UTERINE PROLAPSO UTERINO EM GATA E RETROFLEXÃO UTERINA EM CADELA

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    Giuliano Queiroz Mostachio

    2008-10-01

    Full Text Available

    Obstetrical emergencies are problem in veterinary clinics and hospital. So, the aim of this report is to describe the clinical-surgical aspect of one of them, the uterine prolapse. Complete protrusion and retroflexion of uterus had been diagnosed in a queen and female dog, respectively. After the stabilization of the animals and reduction of the prolapses followed by ovary-hysterectomy, one of the animals came to death due to septicemia and hypovolemic shock. Rapid assessment and intensive treatments are required to sustain the life of the animal.

    KEY WORDS: Cat, dog, uterine prolapse, uterine retroflexion.

    Emergências obstétricas, como o prolapso uterino, constituem um problema em clínicas e hospitais veterinários. Neste relato descreve-se o aspecto clínico-cirúrgico do prolapso uterino. Diagnosticaram-se, em uma gata e em uma cadela, protrusão completa e retroflexão uterina, respectivamente. Após a estabilização dos animais e redução dos prolapsos seguidos de ovário-histerectomia, um dos animais veio a óbito, em decorrência de septicemia e choque hipovolêmico. Portanto, a rápida avaliação e tratamentos intensivos são requeridos para assegurar a vida do animal.

     

    PALAVRAS-CHAVES: Cão, gato, prolapso uterino, retroflexão uterina

  4. Vascularização uterina de éguas prenhes de jumento e de garanhão monitoradas por ultrassonografia Doppler

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    Sabina G.C. Lemos

    Full Text Available RESUMO: Este estudo teve como objetivo analisar e descrever os achados ultrassonográficos do útero de éguas gestantes de diferentes idades, de jumento e garanhão, utilizando a técnica de ultrassonografia Doppler Espectral, visando caracterizar os índices de resistência (RI e pulsatilidade (PI até 154 dias de gestação. Foram utilizadas 20 éguas em idade reprodutiva, sem raça definida. As avaliações foram realizadas nas artérias uterinas. Não foi constatada interação entre os valores de RI e PI obtidos nos cornos uterinos (que iniciaram ou não a gestação com o tempo da gestação (P>0,05, desta forma os dados foram discutidos separadamente. Não foram encontradas diferenças entre as avaliações de RI e PI quando comparado os cornos que iniciaram ou não a gestação (P>0,05. Verificou-se efeito de tempo (P0,05. As éguas gestantes de jumento apresentaram maior vascularização uterina no corno não gestante, que as éguas gestantes do garanhão. Com exceção do RI no lado não gravídico, foi verificado efeito de idade da fêmea sobre o lado da gestação (P<0,05, onde as éguas idosas, tanto no corno que iniciou a gestação e o contralateral, tiveram PI e RI mais altos, ou seja, menos vascularizados. Concluiu-se que a vascularização uterina não apresentou diferença entre os cornos uterinos. Há um aumento da vascularização uterina no 70º dia de gestação. Éguas gestantes de jumentos apresentaram maior vascularização uterina, quando comparada às éguas gestantes de garanhões. Éguas com idade acima de 15 anos apresentaram menor vascularização uterina, quando comparadas com idade inferior a 15 anos.

  5. Rotura Uterina Espontánea en embarazo de segundo trimestre: presentación de un caso y revisión de la literatura

    Directory of Open Access Journals (Sweden)

    Airam Amoroso

    2013-09-01

    Full Text Available La rotura uterina se define como la solución de continuidad de la pared uterina. Es una complicación obstétrica poco frecuente y potencialmente letal para la madre y el feto, que ocurre generalmente durante el segundo o tercer trimestre de gestación, y que está asociada principalmente a la cirugía uterina previa, constituyendo así un desafío médico por su difícil diagnóstico diferencial y controversial manejo. Se presenta el caso de una paciente de 26 años de edad, con rotura espontánea de útero grávido de 18 semanas de gestación y antecedente de cicatriz uterina. Se realiza laparotomía exploradora obteniendo como hallazgo placenta y cordón umbilical unido a feto sin vida en cavidad abdominal, lo que confirma diagnóstico intraoperatorio. Spontaneous Uterine Rupture in Second Trimester of Pregnancy: Case report and Literature review Abstract Uterine rupture is a solution of continuity of the uterine wall. It is an uncommon and potentially lethal obstetric complication, for both mother and fetus, that mainly occurs during the second or third trimester of pregnancy, and that is mainly associated to previous uterine surgery, thus forming a medical challenge for its difficult differential diagnosis and controversial management. We report the case of a 26 years old patient with a spontaneous gravid uterine rupture, 18 weeks of gestation and cesarean scar background. Laparotomy is conducted finding both placenta and umbilical cord attached to no-living fetus in the abdominal cavity, which confirms intraoperative diagnosis.

  6. Carcinoma urotelial primario de la trompa uterina, una patología infrecuente: reporte de un caso

    Directory of Open Access Journals (Sweden)

    Stefano Pozzobon-Borregales

    2013-01-01

    Full Text Available El carcinoma primario de la trompa uterina es una patología maligna infrecuente que ocurre entre el 0,1% al 1,8% de todos los tumores malignos del organismo, siendo aun menos frecuente el tipo histológico transicional o urotelial que representa el 10% de los tumores malignos de trompa uterina. Se presentan principalmente entre la 5ta y 7ma décadas de la vida, y clínicamente se manifiesta, en el 18% de los casos, con la triada de masa palpable y/o distensión abdominal, dolor pélvico y metrorragia. Presentamos el caso de una paciente de 44 años de edad quien inicia enfermedad actual en diciembre del 2010, con antecedente de dolor pélvico y sangrado genital continuo. En la resonancia magnética se apreció un lesión ocupante de espacio parauterina derecha, sugestiva de neoplasia maligna de ovario derecho. El reporte del marcador tumoral Ca 125 mostró valores elevados, acompañado de clínica y paraclínica sugestiva enfermedad tumoral maligna. Se decidió realizar laparotomía ginecológica en la que se evidenció tumoración en trompa uterina derecha. El estudio histológico se concluyó como carcinoma con diferenciación uroterial. Posteriormente se realizó cirugía de estadiaje, que incluyó lavado peritoneal, histerectomía total, salpingooforectomía izquierda, omentectomía subcolónica, apendicectomía y linfadenectomía bilateral selectiva. El reporte de biopsia de dichas piezas operatorias resultaron negativas para malignidad. La paciente se encuentra actualmente libre de enfermedad. Dado lo infrecuente de la patología se reporta este caso. Primary Carcinoma of the uterine tube, an unusual malignant pathology: case report Abstract Primary Carcinoma of the uterine tube is an unusual malignant pathology that occurs between the 0,1% and the 1,8% of all malignant tumors, being the urothelial histological type even less frequent, which represents 10% of malignant tumors of the uterine tubes. These tumors usually appear in women

  7. LA CAPACIDAD ACELERATIVA EN EL DEPORTE

    Directory of Open Access Journals (Sweden)

    Isidoro Hornillos Baz

    2010-01-01

    Full Text Available La capacidad acelerativa adquiere una gran relevancia en las disciplinas deportivas que exigen desplazamientos rápidos. Forma parte de la velocidad, como cualidad motora, en su dimensión compleja. Desde una perspectiva bioenergética, la aceleración depende de la potencia del sistema anaeróbico aláctico. Para mejorar esta capacidad será necesario realizar ejercicios a la máxima intensidad, con recuperaciones completas y con una duración no superior a los seis segundos, en general. También desarrollar las técnicas de salida y de carrera. Los principales medios para la mejora de la aceleración son los multisaltos; las cuestas; los arrastres; los ejercicios con cinturones y tobilleras; los lastres en forma de cinturones, tobilleras o carreras con paracaídas; el entrenamiento de fuerza con cargas y los sprints en terreno liso. Pero en algunos deportes colectivos va a ser determinante la resistencia a la aceleración, debido al alto número de carreras de máxima o alta velocidad durante un partido. En estos casos será también necesario desarrollar la capacidad anaeróbica aláctica y la potencia y capacidad lactácida. Asimismo, hay que alcanzar un mínimo nivel de potencia aeróbica, que representa la máxima cantidad de producción de ATP por unidad de tiempo en base a procesos metabólicos de naturaleza aeróbica.

  8. Actomyosin contractility rotates the cell nucleus.

    Science.gov (United States)

    Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

    2014-01-21

    The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells.

  9. Spontaneous actin dynamics in contractile rings

    Science.gov (United States)

    Kruse, Karsten; Wollrab, Viktoria; Thiagarajan, Raghavan; Wald, Anne; Riveline, Daniel

    Networks of polymerizing actin filaments are known to be capable to self-organize into a variety of structures. For example, spontaneous actin polymerization waves have been observed in living cells in a number of circumstances, notably, in crawling neutrophils and slime molds. During later stages of cell division, they can also spontaneously form a contractile ring that will eventually cleave the cell into two daughter cells. We present a framework for describing networks of polymerizing actin filaments, where assembly is regulated by various proteins. It can also include the effects of molecular motors. We show that the molecular processes driven by these proteins can generate various structures that have been observed in contractile rings of fission yeast and mammalian cells. We discuss a possible functional role of each of these patterns. The work was supported by Agence Nationale de la Recherche, France, (ANR-10-LABX-0030-INRT) and by Deutsche Forschungsgemeinschaft through SFB1027.

  10. Modelo computacional para caracterización de células escamosas de citologías cérvico-uterinas

    OpenAIRE

    Martínez Abaunza Víctor Eduardo; Mendoza Castellanos Alfonso; Uribe Pérez Claudia Janeth

    2005-01-01

    El trabajo se realizó entre el Grupo de Investigación en Ingeniería Biomédica (GIIB) y el Grupo de Investigación en Patología Estructural, Funcional y Clínica de la Universidad Industrial de Santander (UIS), junto con la Facultad de Medicina de la Universidad Autónoma de Bucaramanga (UNAB); el objetivo principal es construir un modelo computacional que permita caracterizar las células presentes en una citología cérvico uterina, con el propósito de clasificarlas como normales o displásicas. La...

  11. Tamizaje y prevención de pre-eclampsia guiado por Doppler de arterias uterinas: revisión sistemática de la literatura

    OpenAIRE

    Sáez O, Nicolás; Carvajal C, Jorge

    2012-01-01

    Antecedentes: La pre-eclampsia (PE) es una enfermedad grave asociada al embarazo con una prevalencia de ~3%. La identificación de las mujeres en riesgo podría mejorar el resultado materno y perinatal. La estimación de riesgo individual de PE permitiría ofrecer un tratamiento preventivo para ésta [ej: aspirina (AAS)]. Se ha descrito el Doppler de arterias uterinas (DAUt) en primer y segundo trimestre como un método de tamizaje de PE. Objetivo: Recopilar la evidencia disponible sobre el uso del...

  12. HEALTHY AND PATHOLOGICAL CHANGES OF MYOMETRIUM: PREGNANT MYOMETRIUM, UTERINE FIBROIDS AND LEIOMYOSARCOMA. Cambios normales y patológicos del miometrio: miometrio del embarazo, fibrosis uterina y leiomiosarcoma

    OpenAIRE

    Pasquapina Ciarmela; Soriful Islam; Pasquale Lamanna; Andrea Tranquilli; Mario Castellucci

    2016-01-01

    El miometrio, la pared muscular del útero, puede modificar su misma masa y las propiedades celulares en el embarazo y también en los tumores como el leiomioma y el leiomiosarcoma. El leiomioma, dicho también fibroma, es un tumor benigno del útero y se considera como  una de las causas más frecuentes de infertilità en el período reproductivo femenino. El leiomiosarcoma, en cambio, es un tumor maligno y agresivo de la musculatura lisa uterina. La presente revisión discute las características ge...

  13. Ultra-sonografia tridimensional em ginecologia: malformações uterinas Three-dimensional ultrasound in gynecology: uterine malformations

    Directory of Open Access Journals (Sweden)

    Adilson Cunha Ferreira

    2007-04-01

    Full Text Available As malformações uterinas são achados pouco comuns na clínica ginecológica. As estatísticas nesta área são muito falhas. Corrobora, ainda, a falta de uniformização na terminologia empregada e as dificuldades diagnósticas. A partir da década de oitenta, a ultra-sonografia tornou-se um procedimento indispensável à prática toco-ginecológica, contribuindo e modificando conceitos e procedimentos dentro dessa especialidade. O advento dos transdutores endocavitários, a análise com Doppler colorido de amplitude e espectral, assim como a melhoria crescente da qualidade de imagem contribuíram para isso. Nos últimos dez anos muito se tem pesquisado, publicado e discutido sobre o papel da ultra-sonografia tridimensional. Os autores fazem uma revisão do tema e ressaltam a importância dessa metodologia como modalidade diagnóstica.Uterine malformations are unusual findings in the clinical practice of gynecology. Statistics regarding this abnormality are flawed, and there is a lack of standardization of the pertinent terminology, besides difficulty in the diagnosis. Starting in the 1980's, ultrasound became a procedure indispensable to the clinical practice in the field of tocogynecology, modifying concepts and procedures, and bringing an important contribution to this specialty. The advent of endocavitary transducers, amplitude and spectral color Doppler, as well as the increasing improvement in the imaging quality, has contributed to this progress. Over the last ten years, much has been studied, published and discussed about the role of the three-dimensional ultrasonography. The authors review the topic and emphasize the importance of this method as a diagnostic modality.

  14. Fatores determinantes da capacidade funcional entre idosos

    Directory of Open Access Journals (Sweden)

    Tereza Etsuko da Costa Rosa

    2003-02-01

    Full Text Available OBJETIVO; Investigar a influência de fatores socioeconômicos e demográficos relativos à saúde, bem como os fatores ligados às atividades sociais e à avaliação subjetiva da saúde sobre a capacidade funcional dos idosos. MÉTODOS: Estudo transversal, integrante de estudo multicêntrico, em amostra representativa do município de São Paulo, realizado em 1989. A capacidade funcional foi avaliada através da escala de atividades da vida diária pessoal e instrumental e investigada como variável dicotômica: ausência de dependência - incapacidade/dificuldade em nenhuma das atividades versus presença de dependência moderada/grave - incapacidade/dificuldade em 4 ou mais atividades. Análise de regressão logística múltipla foi aplicada aos fatores hierarquicamente agrupados. RESULTADOS: As características que se associaram com a dependência moderada/grave foram analfabetismo, ser aposentado, ser pensionista, ser dona de casa, não ser proprietário da moradia, ter mais de 65 anos, ter composição familiar multigeracional, ter sido internado nos últimos 6 meses, ser "caso" no rastreamento de saúde mental, não visitar amigos, ter problemas de visão, ter história de derrame, não visitar parentes e ter avaliação pessimista da saúde ao se comparar com seus pares. CONCLUSÕES: As características identificadas que se associaram à dependência moderada/grave sugerem uma complexa rede causal do declínio da capacidade funcional. Pode-se supor, entretanto, que ações preventivas especificamente voltadas para certos fatores podem propiciar benefícios para o prolongamento do bem estar da população idosa.

  15. Fatores determinantes da capacidade funcional entre idosos

    Directory of Open Access Journals (Sweden)

    Rosa Tereza Etsuko da Costa

    2003-01-01

    Full Text Available OBJETIVO; Investigar a influência de fatores socioeconômicos e demográficos relativos à saúde, bem como os fatores ligados às atividades sociais e à avaliação subjetiva da saúde sobre a capacidade funcional dos idosos. MÉTODOS: Estudo transversal, integrante de estudo multicêntrico, em amostra representativa do município de São Paulo, realizado em 1989. A capacidade funcional foi avaliada através da escala de atividades da vida diária pessoal e instrumental e investigada como variável dicotômica: ausência de dependência - incapacidade/dificuldade em nenhuma das atividades versus presença de dependência moderada/grave - incapacidade/dificuldade em 4 ou mais atividades. Análise de regressão logística múltipla foi aplicada aos fatores hierarquicamente agrupados. RESULTADOS: As características que se associaram com a dependência moderada/grave foram analfabetismo, ser aposentado, ser pensionista, ser dona de casa, não ser proprietário da moradia, ter mais de 65 anos, ter composição familiar multigeracional, ter sido internado nos últimos 6 meses, ser "caso" no rastreamento de saúde mental, não visitar amigos, ter problemas de visão, ter história de derrame, não visitar parentes e ter avaliação pessimista da saúde ao se comparar com seus pares. CONCLUSÕES: As características identificadas que se associaram à dependência moderada/grave sugerem uma complexa rede causal do declínio da capacidade funcional. Pode-se supor, entretanto, que ações preventivas especificamente voltadas para certos fatores podem propiciar benefícios para o prolongamento do bem estar da população idosa.

  16. Cell stiffness, contractile stress and the role of extracellular matrix

    International Nuclear Information System (INIS)

    An, Steven S.; Kim, Jina; Ahn, Kwangmi; Trepat, Xavier; Drake, Kenneth J.; Kumar, Sarvesh; Ling, Guoyu; Purington, Carolyn; Rangasamy, Tirumalai; Kensler, Thomas W.; Mitzner, Wayne; Fredberg, Jeffrey J.; Biswal, Shyam

    2009-01-01

    Here we have assessed the effects of extracellular matrix (ECM) composition and rigidity on mechanical properties of the human airway smooth muscle (ASM) cell. Cell stiffness and contractile stress showed appreciable changes from the most relaxed state to the most contracted state: we refer to the maximal range of these changes as the cell contractile scope. The contractile scope was least when the cell was adherent upon collagen V, followed by collagen IV, laminin, and collagen I, and greatest for fibronectin. Regardless of ECM composition, upon adherence to increasingly rigid substrates, the ASM cell positively regulated expression of antioxidant genes in the glutathione pathway and heme oxygenase, and disruption of a redox-sensitive transcription factor, nuclear erythroid 2 p45-related factor (Nrf2), culminated in greater contractile scope. These findings provide biophysical evidence that ECM differentially modulates muscle contractility and, for the first time, demonstrate a link between muscle contractility and Nrf2-directed responses.

  17. Cell stiffness, contractile stress and the role of extracellular matrix

    Energy Technology Data Exchange (ETDEWEB)

    An, Steven S., E-mail: san@jhsph.edu [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Kim, Jina [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Ahn, Kwangmi [Division of Biostatistics, Penn State College of Medicine, Hershey, PA 17033 (United States); Trepat, Xavier [CIBER, Enfermedades Respiratorias, 07110 Bunyola (Spain); Drake, Kenneth J. [Division of Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA 02115 (United States); Kumar, Sarvesh; Ling, Guoyu; Purington, Carolyn; Rangasamy, Tirumalai; Kensler, Thomas W.; Mitzner, Wayne [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Fredberg, Jeffrey J. [Division of Molecular and Integrative Physiological Sciences, Harvard School of Public Health, Boston, MA 02115 (United States); Biswal, Shyam [Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Room E-7616, Baltimore, MD 21205 (United States); Division of Pulmonary and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21205 (United States)

    2009-05-15

    Here we have assessed the effects of extracellular matrix (ECM) composition and rigidity on mechanical properties of the human airway smooth muscle (ASM) cell. Cell stiffness and contractile stress showed appreciable changes from the most relaxed state to the most contracted state: we refer to the maximal range of these changes as the cell contractile scope. The contractile scope was least when the cell was adherent upon collagen V, followed by collagen IV, laminin, and collagen I, and greatest for fibronectin. Regardless of ECM composition, upon adherence to increasingly rigid substrates, the ASM cell positively regulated expression of antioxidant genes in the glutathione pathway and heme oxygenase, and disruption of a redox-sensitive transcription factor, nuclear erythroid 2 p45-related factor (Nrf2), culminated in greater contractile scope. These findings provide biophysical evidence that ECM differentially modulates muscle contractility and, for the first time, demonstrate a link between muscle contractility and Nrf2-directed responses.

  18. A altura uterina é capaz de diagnosticar os desvios do volume de líquido amniótico? Is uterine height able to diagnose amniotic fluid volume deviations?

    Directory of Open Access Journals (Sweden)

    Djacyr Magna Cabral Freire

    2013-02-01

    Full Text Available OBJETIVO: Avaliar o desempenho de uma curva de altura uterina (AU quanto à capacidade de rastrear desvios do volume de líquido amniótico, utilizando uma curva brasileira de índice de líquido amniótico (ILA como padrão-ouro. MÉTODOS: O presente estudo representa um corte transversal no qual foram incluídas 753 gestantes em acompanhamento pré-natal na rede pública de João Pessoa (PB no período de março a outubro de 2006 e que tiveram um exame de ultrassonografia (US de rotina agendado para depois da 26ª semana de idade gestacional. Foram excluídos os casos com diagnóstico de gestação gemelar, óbito fetal intrauterino e malformações fetais maiores. Além de informações sociodemográficas, foram coletados também os valores da AU medida de forma padronizada, os valores do peso fetal estimado, do ILA e a idade gestacional pelo exame de US. A capacidade da curva de AU em predizer os desvios do volume de líquido amniótico foi avaliada tendo uma curva brasileira de ILA em função da idade gestacional como padrão-ouro. Para isso, foram estimados a sensibilidade, especificidade e valores preditivos positivo e negativo para diferentes pontos de corte. RESULTADOS: A medida da AU identificou 10,5% das mulheres como AU baixa e possivelmente associada ao oligoâmnio, e 25,2% como AU alta e possivelmente associada ao polidrâmnio. Utilizando uma curva brasileira de referência para ILA, a AU foi capaz de predizer pobremente a ocorrência de oligoâmnio (sensibilidade variando entre 37 a 28% e de forma razoável a ocorrência de polidrâmnio (sensibilidade variando entre 88 a 69%. CONCLUSÃO: A medida da altura uterina mostrou um desempenho ruim para predizer oligoâmnio e um desempenho razoável para predizer polidrâmnio. Sua utilização para essa finalidade só se justifica, portanto, em situações nas quais o exame ultrassonográfico não esteja fácil e rotineiramente disponível, a fim de ajudar na priorização dos casos que

  19. Cadmium translocation by contractile roots differs from that in regular, non-contractile roots.

    Science.gov (United States)

    Lux, Alexander; Lackovič, Andrej; Van Staden, Johannes; Lišková, Desana; Kohanová, Jana; Martinka, Michal

    2015-06-01

    Contractile roots are known and studied mainly in connection with the process of shrinkage of their basal parts, which acts to pull the shoot of the plant deeper into the ground. Previous studies have shown that the specific structure of these roots results in more intensive water uptake at the base, which is in contrast to regular root types. The purpose of this study was to find out whether the basal parts of contractile roots are also more active in translocation of cadmium to the shoot. Plants of the South African ornamental species Tritonia gladiolaris were cultivated in vitro for 2 months, at which point they possessed well-developed contractile roots. They were then transferred to Petri dishes with horizontally separated compartments of agar containing 50 µmol Cd(NO3)2 in the region of the root base or the root apex. Seedlings of 4-d-old maize (Zea mays) plants, which do not possess contractile roots, were also transferred to similar Petri dishes. The concentrations of Cd in the leaves of the plants were compared after 10 d of cultivation. Anatomical analyses of Tritonia roots were performed using appropriately stained freehand cross-sections. The process of contraction required specific anatomical adaptation of the root base in Tritonia, with less lignified and less suberized tissues in comparison with the subapical part of the root. These unusual developmental characteristics were accompanied by more intensive translocation of Cd ions from the basal part of contractile roots to the leaves than from the apical-subapical root parts. The opposite effects were seen in the non-contractile roots of maize, with higher uptake and transport by the apical parts of the root and lower uptake and transport by the basal part. The specific characteristics of contractile roots may have a significant impact on the uptake of ions, including toxic metals from the soil surface layers. This may be important for plant nutrition, for example in the uptake of nutrients from

  20. Prevalência de alterações uterinas e tubárias na histerossalpingografia em mulheres inférteis: estudo de 48 casos

    Directory of Open Access Journals (Sweden)

    Pérez Juliano Adams

    2001-01-01

    Full Text Available A histerossalpingografia é um exame realizado para avaliação da anatomia uterina e da permeabilidade tubária, característica esta que torna a pesquisa de causa de infertilidade primária ou secundária sua principal indicação. Este trabalho se propôs a estudar a prevalência de alterações na histerossalpingografia em pacientes com infertilidade. Para tal, foram alocadas todas as pacientes que se submeteram ao exame, num período de quatro meses. Entre as 48 pacientes estudadas, 36 apresentavam infertilidade primária e 12, infertilidade secundária. As pacientes com infertilidade primária apresentaram maior índice de malformações uterinas, enquanto as pacientes com infertilidade secundária apresentaram obstrução tubária como alteração mais freqüente. Não ocorreu nenhuma intercorrência significativa durante a realização dos exames. O trabalho permite afirmar que este exame é muito útil na pesquisa de infertilidade, uma vez que, freqüentemente, diagnostica alterações importantes, sendo um exame barato e de raras complicações.

  1. Contractility Dispersion in Long QT Syndrome

    Directory of Open Access Journals (Sweden)

    MH Nikoo

    2009-09-01

    Full Text Available Background: Previous studies, using M mode echocardiography, provided unexpected evidence of a mechanical alteration in patients with long QT syndrome. The aim of this study was to evaluate entire left ventricular (LV wall motion characteristics in patients with long QT syndrome using tissue Doppler imaging. Methods: We enrolled 17 patients with congenital long QT syndrome [11 female and 6 male], aged 21 to 45 years. 10 subjects without cardiac disease were also selected as a control group. Two-dimensional tissue Doppler imaging (TDI recording of the LV was obtained from the basal and mid-segments from apical four-chamber, two-chamber, and long-axis views. ‘Myocardial Contraction Duration’ [MCD] was defined as the time from start of R wave on ECG to end of S wave on TDI. MCD was measured in the six LV wall positions: septal, anteroseptal, lateral, inferior, posterior and anterior positions.Results: LV contractility dispersion was significantly greater in long QT syndrome patients compared to control group [0.051 ± 0.011 vs. 0.016 ± 0.06; P < 0.001]. Conclusion: Our study evaluated left ventricular dispersion of contractility duration in patients with long QT syndrome. This mechanical dispersion may be a reflection of the inhomogeneity of repolarisation in the long QT syndrome.

  2. Capacidade de Carga em Cidades Históricas

    Directory of Open Access Journals (Sweden)

    Fernando Vicente de Oliveira

    2010-08-01

    Full Text Available Neste artigo são apresentados os conceitos de capacidade de carga e capacidade ambiental vinculando-os ao manejo de cidades históricas dentro dos pressupostos do turismo sustentável. A avaliação da capacidade ambiental é uma valiosa ferramenta para planejamento turístico. O principal é determinar até que ponto um meio ambiente pode suportar uma intervenção, sem que a mesma danifique ou prejudique a característica principal deste local. As cidades históricas e turísticas com desejo de fomentar o turismo devem, necessariamente, delimitar suas capacidades de crescimento, para geração de riquezas através de sua economia diversificada e, sobretudo, bem estar de sua população, principal objetivo do estudo de capacidade ambiental.

  3. Metodologia para avaliação ultrassonográfica da biometria uterina na fêmea bovina

    Directory of Open Access Journals (Sweden)

    Víctor Gómez-L

    2017-07-01

    Full Text Available Objetivou-se avaliar uma metodologia para mensurar a espessura endometrial e diâmetro dos cornos uterinos. Para o qual, os cornos uterinos foram divididos em três regiões. A partir do septo intercornual até o início a curvatura maior, foi considerada a primeira região. A partir da curvatura maior até o início do ápice do corno segunda região, e extremidade livre do corna a terceira região. Mensurou-se a espessura endometrial e o diâmetro dos cornos em animais in vivo e nos órgãos genitais dos mesmos post mortem. Foram utilizadas cinco vacas sexualmente maturas da raça Holandesa, criadas em manejo Losing-House. Os dados quantitativos foram analisados pela ANOVA e as médias comparadas pelos testes de Tukey ou pela análise não paramétrica comparando as médias pelo teste de Kruskall Wallis. Os valores médios não apresentaram diferenças para as características avaliadas no animal in vivo comparadas aos obtidos post mortem (P>0,05. Nas mensurações obtidas, a terceira região mostrou valores médios semelhantes para diâmetro (21,0±2,6 mm - 22,9±2,8 mm e espessura endometrial de ambos cornos (10,4±4,9 mm - 10,8±5,2 mm. De igual forma os valores obtidos para espessura e diâmetro de ambos cornos uterinos da terceira região mostrou-se semelhante aos valores obtidos na segunda e primeira região. Já os valores da segunda região diferiram dos obtidos na primeira região (P<0,05. Dessa forma, a obtenção de imagens ultrassonográficas em cortes transversais e a mensuração das biometrias uterinas a partir da bifurcação até a curvatura maior, mostra-se eficiente e representativa da espessura endometrial e diâmetro dos cornos uterinos como um tudo.

  4. Contractile injection systems of bacteriophages and related systems

    DEFF Research Database (Denmark)

    Taylor, Nicholas M I; van Raaij, Mark J; Leiman, Petr G

    2018-01-01

    Contractile tail bacteriophages, or myobacteriophages, use a sophisticated biomolecular structure to inject their genome into the bacterial host cell. This structure consists of a contractile sheath enveloping a rigid tube that is sharpened by a spike-shaped protein complex at its tip. The spike ...

  5. Genome sequence of Haloplasma contractile, an unusual contractile bacterium from a deep-sea anoxic brine lake.

    KAUST Repository

    Antunes, Andre; Alam, Intikhab; El Dorry, Hamza; Siam, Rania; Robertson, Anthony J.; Bajic, Vladimir B.; Stingl, Ulrich

    2011-01-01

    We present the draft genome of Haloplasma contractile, isolated from a deep-sea brine and representing a new order between Firmicutes and Mollicutes. Its complex morphology with contractile protrusions might be strongly influenced by the presence of seven MreB/Mbl homologs, which appears to be the highest copy number ever reported.

  6. Genome sequence of Haloplasma contractile, an unusual contractile bacterium from a deep-sea anoxic brine lake.

    KAUST Repository

    Antunes, Andre

    2011-09-01

    We present the draft genome of Haloplasma contractile, isolated from a deep-sea brine and representing a new order between Firmicutes and Mollicutes. Its complex morphology with contractile protrusions might be strongly influenced by the presence of seven MreB/Mbl homologs, which appears to be the highest copy number ever reported.

  7. Considerations for Contractile Electroactive Materials and Actuators

    Energy Technology Data Exchange (ETDEWEB)

    Lenore Rasmussen, David Schramm, Paul Rasmussen, Kevin Mullaly, Ras Labs, LLC, Intelligent Materials for Prosthetics & Automation, Lewis D. Meixler, Daniel Pearlman and Alice Kirk

    2011-05-23

    Ras Labs produces contractile electroactive polymer (EAP) based materials and actuators that bend, swell, ripple, and contract (new development) with low electric input. In addition, Ras Labs produces EAP materials that quickly contract and expand, repeatedly, by reversing the polarity of the electric input, which can be cycled. This phenomenon was explored using molecular modeling, followed by experimentation. Applied voltage step functions were also investigated. High voltage steps followed by low voltage steps produced a larger contraction followed by a smaller contraction. Actuator control by simply adjusting the electric input is extremely useful for biomimetic applications. Muscles are able to partially contract. If muscles could only completely contract, nobody could hold an egg, for example, without breaking it. A combination of high and low voltage step functions could produce gross motor function and fine manipulation within the same actuator unit. Plasma treated electrodes with various geometries were investigated as a means of providing for more durable actuation.

  8. LAS CAPACIDADES TECNOLÓGICAS COMO BASE PARA EL DESARROLLO

    OpenAIRE

    Álvaro Carbajal Villaplana

    2010-01-01

    En este artículo interesa determinar la estructura lógica del concepto de capacidades tecnológicas para establecer las características y los componentes más relevantes, esto con la intención de proponer una definición filosófica a partir de las ideas de capacidades y funcionamientos de Amartya Sen y del concepto de disposiciones de Gilbert Ryle. Se trata de una ampliación o aplicación de esas nociones a la idea de capacidades tecnológicas con el fin de obtener dicho concepto operativo y aprop...

  9. Correr el riesgo: ¿desventaja social o capacidad?

    Directory of Open Access Journals (Sweden)

    Luz Adriana Muñoz-Duque

    2018-05-01

    Full Text Available El artículo aborda las nociones de riesgo y aceptabilidad del riesgo desde una perspectiva de justicia social, particularmente, a la luz del enfoque de capacidades propuesto por Amartya Sen. Se argumenta que el riesgo puede ser la expresión de restricciones en las capacidades de los sujetos, partiendo de desventajas sociales que pueden estar normalizadas en su cotidianidad. Por otro lado, puede ser pensado como expresión de capacidad, en aquellos casos en los cuales es aceptado o admitido a través del ejercicio de la libertad, siempre que los sujetos que así se relacionan con el riesgo, lo conciban en consonancia con su idea de una vida buena, cuya construcción implica el desarrollo pleno de la capacidad de agencia. Finalmente, se presentan algunas reflexiones sobre la materia dentro del ámbito de la salud pública.

  10. Ciclo estral, histologia e ultra-estrutura do epitelio da tuba uterina da linhagem de ratos UChA e UChB (bebedores voluntarios de etanol)

    OpenAIRE

    Camila Contin Diniz de Almeida-Francia

    2005-01-01

    Resumo: O alcoolismo é o terceiro problema mais sério de Saúde Pública Mundial. A maioria é constituída de homens, entretanto, o índice de mulheres viciadas em bebidas alcoólicas vem aumentando. A tuba uterina promove o meio necessário para a maturação dos gametas femininos e masculinos (capacitação), a fertilização e o desenvolvimento inicial do embrião. As variedades UChA e UChB constituem modelos para os trabalhos relacionados aos aspectos genéticos, bioquímicos, fisiológicos, nutricionais...

  11. Genetic fuzzy system predicting contractile reactivity patterns of small arteries

    DEFF Research Database (Denmark)

    Tang, J; Sheykhzade, Majid; Clausen, B F

    2014-01-01

    strategies. Results show that optimized fuzzy systems (OFSs) predict contractile reactivity of arteries accurately. In addition, OFSs identified significant differences that were undetectable using conventional analysis in the responses of arteries between groups. We concluded that OFSs may be used...

  12. Regional gastrointestinal contractility parameters using the wireless motility capsule

    DEFF Research Database (Denmark)

    Farmer, A D; Wegeberg, A-M L; Brock, B

    2018-01-01

    BACKGROUND: The wireless motility capsule concurrently measures temperature, pH and pressure as it traverses the gastrointestinal tract. AIMS: To describe normative values for motility/contractility parameters across age, gender and testing centres. METHODS: Healthy participants underwent...

  13. Considerations for Contractile Electroactive Materials and Actuators

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Lenore; Erickson, Carl J.; Meixler, Lewis D.; Ascione, George; Gentile, Charles A.; Tilson, Carl; Bernasek, Stephen L.; Abelev, Esta

    2010-02-19

    Ras Labs produces electroactive polymer (EAP) based materials and actuators that bend, swell, ripple and now contract (new development) with low electric input. This is an important attribute because of the ability of contraction to produce life-like motion. The mechanism of contraction is not well understood. Radionuclide-labeled experiments were conducted to follow the movement of electrolytes and water in these EAPs when activated. Extreme temperature experiments were performed on the contractile EAPs with very favorable results. One of the biggest challenges in developing these actuators, however, is the electrode-EAP interface because of the pronounced movement of the EAP. Plasma treatments of metallic electrodes were investigated in order to improve the attachment of the embedded electrodes to the EAP material. Surface analysis, adhesive testing, and mechanical testing were conducted to test metal surfaces and metal-polymer interfaces. The nitrogen plasma treatment of titanium produced a strong metal-polymer interface; however, oxygen plasma treatment of both stainless steel and titanium produced even stronger metal-polymer interfaces. Plasma treatment of the electrodes allows for the embedded electrodes and the EAP material of the actuator to work and move as a unit, with no detachment, by significantly improving the metal-polymer interface.

  14. Operative contractility: a functional concept of the inotropic state.

    Science.gov (United States)

    Curiel, Roberto; Perez-Gonzalez, Juan; Torres, Edwar; Landaeta, Ruben; Cerrolaza, Miguel

    2005-10-01

    1. Initial unsuccessful attempts to evaluate ventricular function in terms of the 'heart as a pump' led to focusing on the 'heart as a muscle' and to the concept of myocardial contractility. However, no clinically ideal index exists to assess the contractile state. The aim of the present study was to develop a mathematical model to assess cardiac contractility. 2. A tri-axial system was conceived for preload (PL), afterload (AL) and contractility, where stroke volume (SV) was represented as the volume of the tetrahedron. Based on this model, 'operative' contractility ('OperCon') was calculated from the readily measured values of PL, AL and SV. The model was tested retrospectively under a variety of different experimental and clinical conditions, in 71 studies in humans and 29 studies in dogs. A prospective echocardiographic study was performed in 143 consecutive subjects to evaluate the ability of the model to assess contractility when SV and PL were measured volumetrically (mL) or dimensionally (cm). 3. With inotropic interventions, OperCon changes were comparable to those of ejection fraction (EF), velocity of shortening (Vcf) and dP/dt-max. Only with positive inotropic interventions did elastance (Ees) show significantly larger changes. With load manipulations, OperCon showed significantly smaller changes than EF and Ees and comparable changes to Vcf and dP/dt-max. Values of OperCon were similar when AL was represented by systolic blood pressure or wall stress and when volumetric or dimensional values were used. 4. Operative contractility is a reliable, simple and versatile method to assess cardiac contractility.

  15. DIAGNOSIS AND THERAPEUTIC CONSIDERATIONS OF UTERINE INFECTIONS IN DAIRY CATTLE CONSIDERACIONES DIAGNÓSTICAS Y TERAPÉUTICAS PARA INFECCIONES UTERINAS EN VACAS LECHERAS

    Directory of Open Access Journals (Sweden)

    Risco Carlos

    2009-05-01

    Full Text Available From an animal health-well being, welfare, and performance perspective, the postpartum period is comprised of an early window where acute health and cow survival is an issue with the development of septic metritis. Subsequently, sustained presence of endometritis is likely to be contributing to sub-fertility in lactating dairy cows with an overall herd pregnancy rate of approximately 16%. The challenge is to integrate on commercial dairies preventive medicine programs with reproductive management to improve herd fertility. Cows affected by periparturient disorders such as hypocalcemia, dystocia, and retained fetal membranes are more likely to contract uterine infections than cows that calve normally are. Thus, appropriate management of the transition period is critical in the prevention of uterine infections at the herd level. In addition, a postpartum program to monitor health to provide treatment to cows in the early stages of disease should be implemented.Desde el punto de vista del bienestar animal y de la perspectiva de productividad, el periodo postparto puede estar comprometido por una pequeña ventana durante el postparto temprano, en la cual la salud y supervivencia de las vacas es un problemática, debido a la presentación de metritis séptica. Esta se perpetuán subsecuentemente con la presentación de endometritis, la cual muy posiblemente contribuye con los patrones de sub-fertilidad en vacas lactantes, generando en general bajas tasas de preñez del 16 %. El reto es entonces integrar en las explotaciones comerciales un programa de medicina veterinaria preventiva con el manejo reproductivo, con el fin de mejorar la fertilidad del hato. Se ha descrito que las vacas que sufren problemas durante el periparto tales como hipocalcemia y retención de las membranas fetales son más susceptibles de contraer infecciones uterinas, comparadas con aquellas vacas que tienen un parto normal. Por ello un manejo apropiado del periodo de transici

  16. Invertir para el futuro: el fortalecimiento de capacidades en Marruecos

    OpenAIRE

    André, Mathieu; Charlet, France

    2007-01-01

    En 2006, a petición de ACNUR, la ONG francesa Forum Réfugiés dirigió dos misiones para ayudar a reforzar la capacidad local en Marruecos con el fin de proporcionar asistencia letrada y asesoramiento a los solicitantes de asilo y los refugiados.

  17. LAS CAPACIDADES TECNOLÓGICAS COMO BASE PARA EL DESARROLLO

    Directory of Open Access Journals (Sweden)

    Álvaro Carbajal Villaplana

    2010-01-01

    Full Text Available En este artículo interesa determinar la estructura lógica del concepto de capacidades tecnológicas para establecer las características y los componentes más relevantes, esto con la intención de proponer una definición filosófica a partir de las ideas de capacidades y funcionamientos de Amartya Sen y del concepto de disposiciones de Gilbert Ryle. Se trata de una ampliación o aplicación de esas nociones a la idea de capacidades tecnológicas con el fin de obtener dicho concepto operativo y apropiado. El estudio se lleva a cabo, porque la noción de capacidades tecnológicas es muy utilizada en diversos textos de economía, administración, tecnología y filosofía, pero sin que se las defina apropiadamente ni se les fundamente filosóficamente. La investigación en la que se sustenta el artículo se realizó en el año 2005 con un enfoque de análisis inscrito en la tradición filosófica analítica.

  18. Calcium-responsive contractility during fertilization in sea urchin eggs.

    Science.gov (United States)

    Stack, Christianna; Lucero, Amy J; Shuster, Charles B

    2006-04-01

    Fertilization triggers a reorganization of oocyte cytoskeleton, and in sea urchins, there is a dramatic increase in cortical F-actin. However, the role that myosin II plays during fertilization remains largely unexplored. Myosin II is localized to the cortical cytoskeleton both before and after fertilization and to examine myosin II contractility in living cells, Lytechinus pictus eggs were observed by time-lapse microscopy. Upon sperm binding, a cell surface deflection traversed the egg that was followed by and dependent on the calcium wave. The calcium-dependence of surface contractility could be reproduced in unfertilized eggs, where mobilization of intracellular calcium in unfertilized eggs under compression resulted in a marked contractile response. Lastly, inhibition of myosin II delayed absorption of the fertilization cone, suggesting that myosin II not only responds to the same signals that activate eggs but also participates in the remodeling of the cortical actomyosin cytoskeleton during the first zygotic cell cycle. (c) 2006 Wiley-Liss, Inc.

  19. Blood pressure and the contractility of a human leg muscle.

    Science.gov (United States)

    Luu, Billy L; Fitzpatrick, Richard C

    2013-11-01

    These studies investigate the relationships between perfusion pressure, force output and pressor responses for the contracting human tibialis anterior muscle. Eight healthy adults were studied. Changing the height of tibialis anterior relative to the heart was used to control local perfusion pressure. Electrically stimulated tetanic force output was highly sensitive to physiological variations in perfusion pressure showing a proportionate change in force output of 6.5% per 10 mmHg. This perfusion-dependent change in contractility begins within seconds and is reversible with a 53 s time constant, demonstrating a steady-state equilibrium between contractility and perfusion pressure. These stimulated contractions did not produce significant cardiovascular responses, indicating that the muscle pressor response does not play a major role in cardiovascular regulation at these workloads. Voluntary contractions at forces that would require constant motor drive if perfusion pressure had remained constant generated a central pressor response when perfusion pressure was lowered. This is consistent with a larger cortical drive being required to compensate for the lost contractility with lower perfusion pressure. The relationship between contractility and perfusion for this large postural muscle was not different from that of a small hand muscle (adductor pollicis) and it responded similarly to passive peripheral and active central changes in arterial pressure, but extended over a wider operating range of pressures. If we consider that, in a goal-oriented motor task, muscle contractility determines central motor output and the central pressor response, these results indicate that muscle would fatigue twice as fast without a pressor response. From its extent, timing and reversibility we propose a testable hypothesis that this change in contractility arises through contraction- and perfusion-dependent changes in interstitial K(+) concentration.

  20. Comparison of contractile and extensile pneumatic artificial muscles

    Science.gov (United States)

    Pillsbury, Thomas E.; Wereley, Norman M.; Guan, Qinghua

    2017-09-01

    Pneumatic artificial muscles (PAMs) are used in robotic and prosthetic applications due to their high power to weight ratio, controllable compliance, and simple design. Contractile PAMs are typically used in traditional hard robotics in place of heavy electric motors. As the field of soft robotics grows, extensile PAMs are beginning to have increased usage. This work experimentally tests, models, and compares contractile and extensile PAMs to demonstrate the advantages and disadvantages of each type of PAM and applications for which they are best suited.

  1. Effect of cadmium on myocardial contractility and calcium fluxes

    International Nuclear Information System (INIS)

    Pilati, C.F.

    1979-01-01

    The effect of cadmium on myocardial mechanical performance and calcium fluxes was studied in kitten isometric papillary muscles and in isovolumic Langendorff-perfused rabbit hearts. Therefore, it is concluded that cadmium-induced decreases in contractility are not primarily the result of cadmium interference with ATP metabolic processes. Furthermore, these results imply that cadmium causes no structural alterations of the contractile proteins. These data suggest that cadmium may be competing with the calcium needed for excitation-contraction coupling. During experiments using radioisotopic calcium, a statistically significant cellular influx of calcium was observed following the onset of 100 μM Cd ++ perfusion of isolated, Langendorff-prepared rabbit hearts

  2. HEALTHY AND PATHOLOGICAL CHANGES OF MYOMETRIUM: PREGNANT MYOMETRIUM, UTERINE FIBROIDS AND LEIOMYOSARCOMA. Cambios normales y patológicos del miometrio: miometrio del embarazo, fibrosis uterina y leiomiosarcoma

    Directory of Open Access Journals (Sweden)

    Pasquapina Ciarmela

    2016-03-01

    Full Text Available El miometrio, la pared muscular del útero, puede modificar su misma masa y las propiedades celulares en el embarazo y también en los tumores como el leiomioma y el leiomiosarcoma. El leiomioma, dicho también fibroma, es un tumor benigno del útero y se considera como  una de las causas más frecuentes de infertilità en el período reproductivo femenino. El leiomiosarcoma, en cambio, es un tumor maligno y agresivo de la musculatura lisa uterina. La presente revisión discute las características generales del leiomioma y el leiomiosarcoma y los relativos tratamientos clínicos actualmente usados y además describe las características del miometrio normal en el embarazo.  The myometrium, the muscular wall of the uterus, can modify its mass and cellular properties in pregnancy as well as in tumor conditions such as leiomyoma and leiomyosarcoma. Leiomyomas, also known as fibroids, are benign tumors of the uterus, considered to be one of the most frequent causes of infertility in reproductive years of women. Leiomyosarcomas in turn, are rare aggressive malignant uterine smooth-muscle tumors. The present review is discussing the general features of leiomyoma and leiomyosarcoma with their current treatments and also discussing the characteristics of normal pregnant myometrium and compare with leiomyoma.

  3. Cuerpos, capacidades, exigencias funcionales... y otros lechos de Procusto Cuerpos, capacidades, exigencias funcionales... y otros lechos de Procusto

    Directory of Open Access Journals (Sweden)

    Mario Toboso Martín

    2010-03-01

    Full Text Available El denominado modelo social de la discapacidad interpreta ésta como una construcción social, pero no presenta de la misma manera la capacidad. Habitualmente se supone que las capacidades lo son propiamente del cuerpo, mientras que se pasa por alto que llegar a poseer un determinado conjunto de capacidades es un hecho normativamente impuesto por nuestros patrones culturales de vida. Las capacidades que definen este conjunto retratan fielmente las capacidades de lo que aquí denominamos cuerpo normativo. La reflexión en torno al cuerpo, como elemento sociocultural clave, debe cuestionar el esencialismo en la atribución de tales capacidades, notando que el primer paso para caer bajo las miradas médica y capacitista es, precisamente, definir y asumir un conjunto previo de capacidades inherentes atribuibles al cuerpo. Como vía para la deconstrucción del cuerpo normativo nos planteamos poner en práctica una mirada alternativa, que se sitúe lejos de la creencia generalizada en un modo de funcionamiento mayoritario y único, y permita también tener en cuenta los modos minoritarios y menos habituales. La reflexión se convierte así en una cuestión de respeto a la diversidad funcional que, como condición inherente al cuerpo y al ser humano, resulta del reconocimiento de todas las expresiones diferentes de funcionamiento posibles.The so-called social model of disability interprets it as a social construction, but it does not present capability in the same manner. Usually abilities are supposed to be inherent to the body, whereas is overlooked that being able to reach certain set of abilities is an imposed normative fact demanded by our cultural life standards. This set defining abilities reflects accurately the abilities of what we call normative body. The reflection around the body, as a key sociocultural element, must question the essentialism in the attribution of such abilities, remarking that the first step to fall under medical and able

  4. Inhalation of Budesonide/Formoterol Increases Diaphragm Muscle Contractility

    Directory of Open Access Journals (Sweden)

    Chiyohiko Shindoh

    2012-01-01

    Conclusions: BUD/FORM inhalation has an inotropic effect on diaphragm muscle, protects diaphragm muscle deterioration after endotoxin injection, and inhibits NO production. Increments in muscle contractility with BUD/FORM inhalation are induced through a synergistic effect of an anti-inflammatory agent and 02-agonist.

  5. Clinical Relationship between Steatocholecystitis and Gallbladder Contractility Measured by Cholescintigraphy

    Directory of Open Access Journals (Sweden)

    Chang Seok Bang

    2015-01-01

    Full Text Available Objective. Contractility of gallbladder is known to be decreased in fatty gallbladder diseases. However, clinical estimation data about this relationship is still lacking. The aim of this study was to investigate the association between steatocholecystitis and contractility of gallbladder. Methods. Patients with cholecystitis (steatocholecystitis versus nonsteatocholecystitis who underwent cholescintigraphy before cholecystectomy were retrospectively evaluated in a single teaching hospital of Korea. The association of steatocholecystitis with contractility of gallbladder, measured by preoperative cholescintigraphy, was assessed by univariable and multivariable analysis. Results. A total of 432 patients were finally enrolled (steatocholecystitis versus nonsteatocholecystitis; 75 versus 357, calculous versus acalculous cholecystitis; 316 versus 116. In the multivariable analysis, age (OR: 0.94, 95% CI: 0.90–0.99, P=0.01 and total serum cholesterol (OR: 1.02, 95% CI: 1.01–1.04, P=0.04 were related to steatocholecystitis in patients with acalculous cholecystitis. Only age (OR: 0.97, 95% CI: 0.94–0.99, P=0.004 was significantly related to steatocholecystitis in patients with calculous cholecystitis. However, ejection fraction of gallbladder reflecting contractility measured by cholescintigraphy was not related to steatocholecystitis irrespective of presence of gallbladder stone in patients with cholecystitis. Conclusion. Ejection fraction of gallbladder measured by cholescintigraphy cannot be used for the detection or confirmation of steatocholecystitis.

  6. Myocardial contractile function in survived neonatal piglets after cardiopulmonary bypass

    Directory of Open Access Journals (Sweden)

    Popov Aron-Frederik

    2010-11-01

    Full Text Available Abstract Background Hemodynamic function may be depressed in the early postoperative stages after cardiac surgery. The aim of this study was the analysis of the myocardial contractility in neonates after cardiopulmonary bypass (CPB and mild hypothermia. Methods Three indices of left ventricular myocardial contractile function (dP/dt, (dP/dt/P, and wall thickening were studied up to 6 hours after CPB in neonatal piglets (CPB group; n = 4. The contractility data were analysed and then compared to the data of newborn piglets who also underwent median thoracotomy and instrumentation for the same time intervals but without CPB (non-CPB group; n = 3. Results Left ventricular dP/dtmax and (dP/dtmax/P remained stable in CPB group, while dP/dtmax decreased in non-CPB group 5 hours postoperatively (1761 ± 205 mmHg/s at baseline vs. 1170 ± 205 mmHg/s after 5 h; p max and (dP/dtmax/P there were no statistically significant differences between the two groups. Comparably, although myocardial thickening decreased in the non-CPB group the differences between the two groups were not statistically significant. Conclusions The myocardial contractile function in survived neonatal piglets remained stable 6 hours after cardiopulmonary bypass and mild hypothermia probably due to regional hypercontractility.

  7. Stalk-length-dependence of the contractility of Vorticella convallaria

    Science.gov (United States)

    Gul Chung, Eun; Ryu, Sangjin

    2017-12-01

    Vorticella convallaria is a sessile protozoan of which the spasmoneme contracts on a millisecond timescale. Because this contraction is induced and powered by the binding of calcium ions (Ca2+), the spasmoneme showcases Ca2+-powered cellular motility. Because the isometric tension of V. convallaria increases linearly with its stalk length, it is hypothesized that the contractility of V. convallaria during unhindered contraction depends on the stalk length. In this study, the contractile force and energetics of V. convallaria cells of different stalk lengths were evaluated using a fluid dynamic drag model which accounts for the unsteadiness and finite Reynolds number of the water flow caused by contracting V. convallaria and the wall effect of the no-slip substrate. It was found that the contraction displacement, peak contraction speed, peak contractile force, total mechanical work, and peak power depended on the stalk length. The observed stalk-length-dependencies were simulated using a damped spring model, and the model estimated that the average spring constant of the contracting stalk was 1.34 nN µm-1. These observed length-dependencies of Vorticella’s key contractility parameters reflect the biophysical mechanism of the spasmonemal contraction, and thus they should be considered in developing a theoretical model of the Vorticella spasmoneme.

  8. REFLEXOS DAS CAPACIDADES MERCADOLÓGICAS NO DESEMPENHO: HOTELARIA EXECUTIVA

    Directory of Open Access Journals (Sweden)

    Deosir Flávio Lobo de Castro Júnior

    2016-03-01

    Full Text Available O objetivo deste artigo é analisar a relação entre as capacidades mercadológicas e o desempenho dos hotéis executivos em Santa Catarina. Para isto se faz necessário, identificar as variáveis relacionadas as capacidades mercadológicas, observar as variáveis relacionadas ao desempenho na hotelaria executiva e especificar as características do setor da hotelaria executiva. A metodologia empregada na pesquisa foi composta pela abordagem, quantitativo-descritivo, que é o caso da pesquisa descritiva, havendo teste de hipótese, o tipo e estratégia utilizado foi utilizado a survey, o universo e amostra foram os hotéis executivos de Santa Catarina., Após as técnicas estatísticas descritivas de análise do material empírico que foram utilizadas e pela análise multivariada de dados. As conclusões apontam para esta relação e a importância do aumento das capacidades mercadológicas da organização em ambiente dinâmico.

  9. Acurácia da histeroscopia na avaliação da cavidade uterina em pacientes com sangramento uterino pós-menopausa

    Directory of Open Access Journals (Sweden)

    Machado Maria Karenina N.

    2003-01-01

    Full Text Available OBJETIVO: investigar a acurácia da histeroscopia como método de estudo da cavidade uterina de pacientes com sangramento na pós-menopausa. MÉTODO: trata-se de estudo transversal, que consistiu na avaliação de 78 prontuários de pacientes menopausadas com queixa de sangramento, no período de janeiro de 2000 a junho de 2002 no Centro Estadual de Oncologia do Estado da Bahia, submetidas à histeroscopia com biópsia de endométrio. Os achados histeroscópicos foram classificados como benignos (miomas, pólipos, atrofia, normal e suspeitos (espessamento, hiperplasias e câncer e os achados histopatológicos como benignos (miomas, pólipos, atrofia, hiperplasia típica e malignos (hiperplasia atípica e câncer. Os resultados da histeroscopia foram comparados com os exames histopatológicos. RESULTADOS: em relação aos achados suspeitos (espessamento, hiperplasias e câncer, a sensibilidade da histeroscopia foi de 85,7% e a especificidade de 88,7%, quando comparados à histopatologia. O valor preditivo positivo foi de 42,8% e o negativo 98,4%. A razão de probabilidades do teste positivo e a razão de probabilidades do teste negativo foram respectivamente 7,6 e 0,16. A acuidade da histeroscopia foi de 88,4% e o índice kappa 0,5. CONCLUSÃO: a histeroscopia isoladamente não apresentou, no presente estudo, acurácia aceitável, reforçando o conceito de que sua principal vantagem é dirigir a biópsia, devendo sempre estar associada ao diagnóstico histopatológico.

  10. Protein kinase Cα deletion causes hypotension and decreased vascular contractility.

    Science.gov (United States)

    Wynne, Brandi M; McCarthy, Cameron G; Szasz, Theodora; Molina, Patrick A; Chapman, Arlene B; Webb, R Clinton; Klein, Janet D; Hoover, Robert S

    2018-03-01

    Protein kinase Cα (PKCα) is a critical regulator of multiple cell signaling pathways including gene transcription, posttranslation modifications and activation/inhibition of many signaling kinases. In regards to the control of blood pressure, PKCα causes increased vascular smooth muscle contractility, while reducing cardiac contractility. In addition, PKCα has been shown to modulate nephron ion transport. However, the role of PKCα in modulating mean arterial pressure (MAP) has not been investigated. In this study, we used a whole animal PKCα knock out (PKC KO) to test the hypothesis that global PKCα deficiency would reduce MAP, by a reduction in vascular contractility. Radiotelemetry measurements of ambulatory blood pressure (day/night) were obtained for 18 h/day during both normal chow and high-salt (4%) diet feedings. PKCα mice had a reduced MAP, as compared with control, which was not normalized with high-salt diet (14 days). Metabolic cage studies were performed to determine urinary sodium excretion. PKC KO mice had a significantly lower diastolic, systolic and MAP as compared with control. No significant differences in urinary sodium excretion were observed between the PKC KO and control mice, whether fed normal chow or high-salt diet. Western blot analysis showed a compensatory increase in renal sodium chloride cotransporter expression. Both aorta and mesenteric vessels were removed for vascular reactivity studies. Aorta and mesenteric arteries from PKC KO mice had a reduced receptor-independent relaxation response, as compared with vessels from control. Vessels from PKC KO mice exhibited a decrease in maximal contraction, compared with controls. Together, these data suggest that global deletion of PKCα results in reduced MAP due to decreased vascular contractility.

  11. Propuesta para evaluar la capacidad de procesos de manufactura multivariados

    Directory of Open Access Journals (Sweden)

    Manuel Alberto Rodriguez Medina

    2014-08-01

    Full Text Available Los productos manufacturados hoy en día poseen varias características de calidad que son importantes para el cliente y cuando no están correlacionadas, se usan varios índices de capacidad, tales como el Cp, Cpk y Cpm para evaluar la habilidad que tiene el proceso de producir productos de calidad. Para el caso contrario, se encontró en la revisión de literatura, índices de capacidad propuestos para medir la capacidad de un proceso cuando las características de calidad están correlacionadas. La mayoría de las propuestas coinciden en que debe definirse una región de especificación que represente lo que el cliente desea y otra región de variación del proceso que muestre el desempeño que tiene el proceso. Adicionalmente, como resultados de la revisión anterior, se observa que los autores difieren en la forma de definir ambas regiones, oportunidad que se aprovecha para presentar una nueva propuesta, mediante la cual se definen de una manera confiable ambas regiones y que al compararlas se obtienen un par de índices de capacidad multivariados CpM y CpkM, que son extensiones de los índices univariados Cp y Cpk. Por último, se utilizan los datos de un proceso, los cuales se pueden modelar por medio de una distribución normal bivariada para calcular los índices de capacidad propuestos en este trabajo, posteriormente se comparan con el valor de otros índices de capacidad similares, propuestos por otros autores, obteniéndose un desempeño por sobre otros índices de la literatura consultada. The manufactured products have several quality characteristics that are important for the customer. When the quality characteristics are not correlated, using several indices, such as Cp, Cpk and Cpm to assess the ability of the process to produce quality products. For the opposite case was found in the literature review, proposed capability indices to measure the ability of a process when the quality characteristics are correlated. Most proposals

  12. Recently active contractile deformation in the forearc of southern Peru

    Science.gov (United States)

    Hall, S. R.; Farber, D.; Audin, L.; Finkel, R. C.

    2010-12-01

    In the Precordillera and Western Cordillera of southern Peru (14°-18°S), vast pediment surfaces have been abandoned through drainage diversion and river incision, with the major drainages carving deep canyons. Within this region, we have identified range-sub-parallel contractile structures that accommodate significant distributed crustal deformation. Young geomorphic features document both the presence and youthfulness of these contractile structures. Here, we determine exposure ages on geomorphic features such as pediment surfaces and fluvial terraces using in situ produced cosmogenic radionuclides, in conjunction with field and remote mapping. This chronologic data reveals that ancient surfaces have been preserved as a result of very low erosion rates. We measure this rate to be chronology and geomorphic mapping, we calculate a Pleistocene river incision rate of ~0.3mm/yr determined from data collected along exoreic rivers. This rate is consistent with longer-term incision rates measured in other localities along this margin. We suggest that, in this region of southern Peru, the steep western wedge of the Andean margin supports the high topography of the Altiplano through a combination of uplift along steeply dipping contractile west-vergent structures and isostatic responses to the focused removal of large amounts of crustal material through canyon incision. Further, that these range sub-parallel structures are related at depth to a thrust system that plays a role in not only the maintenance of the Andean margin, but potentially in its formation as well.

  13. Effects of hypoxia and hypercapnia on geniohyoid contractility and endurance.

    Science.gov (United States)

    Salmone, R J; Van Lunteren, E

    1991-08-01

    Sleep apnea and other respiratory diseases produce hypoxemia and hypercapnia, factors that adversely affect skeletal muscle performance. To examine the effects of these chemical alterations on force production by an upper airway dilator muscle, the contractile and endurance characteristics of the geniohyoid muscle were examined in situ during severe hypoxia (arterial PO2 less than 40 Torr), mild hypoxia (PO2 45-65 Torr), and hypercapnia (PCO2 55-80 Torr) and compared with hyperoxic-normocapnic conditions in anesthetized cats. Muscles were studied at optimal length, and contractile force was assessed in response to supramaximal electrical stimulation of the hypoglossal nerve (n = 7 cats) or geniohyoid muscle (n = 2 cats). There were no significant changes in the twitch kinetics or force-frequency curve of the geniohyoid muscle during hypoxia or hypercapnia. However, the endurance of the geniohyoid, as reflected in the fatigue index (ratio of force at 2 min to initial force in response to 40-Hz stimulation at a duty cycle 0.33), was significantly reduced by severe hypoxia but not by hypercapnia or mild hypoxia. In addition, the downward shift in the force-frequency curve after the repetitive stimulation protocol was greater during hypoxia than hyperoxia, especially at higher frequencies. In conclusion, the ability of the geniohyoid muscle to maintain force output during high levels of activation is adversely affected by severe hypoxia but not mild hypoxia or hypercapnia. However, none of these chemical perturbations affected muscle contractility acutely.

  14. Capacidad funcional y salud: orientaciones para cuidar al adulto mayor

    Directory of Open Access Journals (Sweden)

    CLARA INÉS GIRALDO M

    2008-07-01

    Full Text Available Objetivo: valorar la salud y la capacidad funcional de ancianos con dependencia funcional para el autocuidado, como elementos para orientar el cuidado de enfermería y el cuidado familiar en casa. Metodología: estudio descriptivo transversal en 40 personas de 65 y más años con dependencia funcional, cuidados por familiar, en Envigado Colombia; muestreo por conveniencia. Valoración de la capacidad funcional con el índice de Katz y la escala de Lawton y Brody, ajustados según grupo de Neurociencias, Universidad de Antioquia. Hallazgos: población entre 67 y 98 años, edad promedio 84,08 años; 82,5% mujeres. Sistemas orgánicos más afectados: cardiovascular, osteomuscular y neurológico; entre 47,5% y 27,5% de los ancianos los tenían comprometidos. Se identificaron dos comportamientos: los hombres, y las personas de edad más avanzada, con mayores grados de dependencia en las actividades básicas e instrumentales; no se determinó asociación estadística por el pequeño tamaño muestral. Las actividades básicas estaban afectadas así: entre el 67,5% y el 55% de los ancianos requería ayuda; y las actividades instrumentales estuvieron comprometidas: entre el 95% y el 75% de los ancianos son totalmente dependientes en ellas. Conclusiones: Enfermería ha de considerar la valoración de la capacidad funcional articulada al estado de salud integral de los ancianos, para orientar su cuidado y apoyar a los cuida-dores familiares. Esto además previene dependencias de cuidado innecesarias que estarían en contra de las aspiraciones del adulto mayor como individuo autónomo e independiente. Es tarea de profesionales en enfermería capacitar a cuidadores familiares sobre valoración de la capacidad funcional.

  15. Justicia social en clave de capacidades y reconocimiento

    OpenAIRE

    Fascioli, Ana

    2011-01-01

    La teoría del reconocimiento de Axel Honneth es un intento de crear una visión ampliada de la justicia social e interpreta los problemas distributivos como problemas de reconocimiento. Este artículo analiza, sin embargo, las insuficiencias de la teoría de Honneth al momento de abordar la justicia distributiva, y propone que la misma puede ser complementada con la base informacional que propone el enfoque de las capacidades de Amartya Sen y Martha Nussbaum. A su vez, se sugiere cómo tal enfoqu...

  16. Estudo ultra-sonográfico da involução uterina pós-parto em cadelas Ultrasonography study of the post-partum uterine involution in bitches

    Directory of Open Access Journals (Sweden)

    S.T.S. Ferri

    2002-02-01

    Full Text Available Utilizando-se 15 cadelas no pós-parto, são descritas as características da involução uterina e determinado o diâmetro do útero, por meio de exames seriados de ultra-som em modo B (tempo real, no período de zero a 28 dias pós-parto. O diâmetro uterino declina progressivamente, sem influência da ordem de parto ou tamanho da ninhada. As características ultra-sonográficas do útero são melhor visualizadas na primeira semana pós-parto e a qualidade da imagem diminui com o progresso da involução. Pela técnica usada são visualizadas apenas três camadas constituintes da parede uterina.The ultrasonographic characteristics and the involution of the uterus were described in 15 pregnant bitches by serial B-mode (real time technique at period of 0 to 28 days postpartum. The uterine diameter decreased progressively, without influence of parity or litter size. The ultrasonographic image of the uterus is better view in the first week and the image quality is poor at subsequent weeks. The uterus was composed of only three ecographic layers.

  17. con la generación de capacidades innovativas

    Directory of Open Access Journals (Sweden)

    Matilde Flores Urbáez

    2005-01-01

    Full Text Available En el presente artículo se destacan los diferentes enfoques teóricos sobre la gerencia del conocimiento en términos de su relación con la generación de capacidades innovativas y el aprendizaje organizacional. Uno de los procesos que ha favorecido el auge de la gerencia del conocimiento es la globalización. Se intenta con el contenido de este artículo comprender, en primer lugar los principios más esenciales de cada uno de los referentes teóricos analizados y en segundo lugar, la relación entre ellos. Se concluye que las empresas inmersas en un entorno cambiante, característico del mundo globalizado, así como los cambios motivados por la misma empresa, han acelerado en ellas la generación y adquisición de nuevos conocimientos y capacidades innovativas para alcanzar posiciones competitivas.

  18. Validación del Protocolo para el Estudio de la Hemorragia Uterina Anormal con Ecografía endovaginal y medio de Contraste (Sonohisterografía.

    Directory of Open Access Journals (Sweden)

    Ricardo Rueda Saenz

    2003-08-01

    Full Text Available

    La evaluación del sangrado uterino anormal (SUA especialmente en los años postreproductivos, convencionalmente se hace recurriendo a las biopsias y aspiraciones endometriales ciegas en el consultorio, o al curetaje uterino bajo anestesia general. Dichos procedimientos, además de ser invasivos, han mostrado ser poco sensibles y específicos en la detección y el tratamiento de la patología focal del endometrio (pólipos, leiomiomas submucosos, y además pueden resultar costosos. Con el advenimiento de la histeroscopia, se han obviado muchas de las dificultades atribuidas a la biopsia ciega y el curetaje uterino, pero aquella, además de requerir un entrenamiento específico y un equipo costoso, requiere de anestesia local o general, en ocasiones dilatación del cervix y en muchas instancias arroja resultados negativos.

    De otro lado, la histeroscopia sólo permite evaluar el canal cervical y la cavidad endometrial, sin poder visualizar la pared miometrial, los anexos y otras estructuras pélvicas, lo cual desvirtúa su uso en una gran proporción de pacientes como investigación inicial rutinaria en el sangrado uterino anormal.

    La utilización de la ecografía transvaginal con contraste líquido (sonohisterografía o histerosonografía permite, por el contrario, no solamente una evaluación precisa y detallada del canal cervical y la cavidad endometrial, sino que permite evaluar la pared miometrial, los ovarios y otras estructuras pélvicas, así como la permeabilidad de las trompas uterinas.

    Este procedimiento tiene además un bajo costo, no requiere de entrenamiento especial, tampoco de anestesia ni de dilatación cervical y tiene bajas tasas de complicaciones. Con la sonohisterografía se pueden seleccionar en forma eficiente y rápida, las mujeres que realmente se benefician de una histeroscopia diagnóstica-operatoria o de una biopsia endometrial ciega de consultorio para evaluar el SUA.

    El presente estudio

  19. Importância dos parâmetros seminais nos resultados de inseminação intra-uterina

    Directory of Open Access Journals (Sweden)

    Borges Junior Edson

    2003-01-01

    Full Text Available OBJETIVOS: analisar a relevância dos parâmetros seminais nos resultados dos ciclos de inseminação intra-uterina (IIU em pacientes com causa masculina de infertilidade e salientar o caráter prognóstico de cada parâmetro para o sucesso da técnica. MÉTODOS: duzentos e trinta e nove ciclos de IIU (155 casais foram analisados durante período de 15 meses. Todos as pacientes foram submetidas à indução da ovulação de acordo com protocolos do I Consenso Brasileiro de Indução de Ovulação. A análise seminal foi realizada de acordo com os critérios da Organização Mundial da Saúde (OMS para parâmetros como concentração e motilidade e critério estrito de Kruger para avaliação da morfologia. O preparo da amostra para IIU foi realizado por meio de gradientes descontínuos de densidade (ISolate®. Foram formados dois grupos de pacientes de acordo com o resultado de gestação: grupo G - gestação positiva e grupo NG - gestação negativa. RESULTADOS: não houve diferença significativa nos valores obtidos relacionados à concentração total de espermatozóides/mL de sêmen, motilidade total, motilidade de formas progressivas antes e depois do processamento seminal. Quando a morfologia estrita de Kruger foi comparada entre os dois grupos, diferenças significativas foram encontradas (grupo G=10,6% de formas normais; grupo NG=6,4% de formas normais; p<0.05 quando o número de espermatozóides/mL inseminados foi superior a 15 milhões/mL, a taxa de gravidez foi significantemente maior. CONCLUSÕES: tanto a morfologia estrita de Kruger como o número de espermatozóides inseminados parecem ser fatores prognósticos positivos para o estabelecimento da gestação, devendo ser salientados na investigação do homem infértil.

  20. Alterações na gasometria de fetos aloimunizados após procedimento de transfusão intra-uterina

    Directory of Open Access Journals (Sweden)

    Nomura Roseli Mieko Yamamoto

    2003-01-01

    Full Text Available OBJETIVO: este estudo, realizado em gestações com aloimunização pelo fator Rh, tem como objetivo descrever as alterações gasométricas e do equilíbrio ácido-básico fetal antes e após transfusões intra-uterinas (TIU. MÉTODO: no período de junho de 2001 a outubro de 2001, antes e após a TIU em fetos de gestantes aloimunizadas, foram avaliados prospectivamente a gasometria e o equilíbrio ácido-básico no sangue da veia umbilical. As medidas foram realizadas em 8 amostras de sangue de 5 fetos. O sangue fetal foi obtido por cordocentese da veia umbilical antes e após TIU. Os resultados obtidos foram comparados com a expansão volêmica na TIU, a idade gestacional no procedimento, o peso fetal estimado pela ultra-sonografia e as variações da hemoglobina fetal (g/dL. RESULTADOS: em todos os casos foi observada queda nos valores do pH, com redução média de 0,09 (DP=0,02. A hemoglobina fetal apresentou aumento médio de 8,4 g/dL (DP=2,9 g/dL. Foi constatada também variação negativa da pO2 (média = -1,28 mmHg na concentração de HCO3_ (média = _2,25 mEq/l. Houve aumento da pCO2 (média = 3,2 mmHg e redução nos valores do excesso de bases (média = -3,75. CONCLUSÃO: a análise das gasometrias permite concluir que o procedimento de TIU acompanha-se de queda nos valores do pH de sangue de veia umbilical, demonstrando haver acidemia fetal relativa após o procedimento.

  1. Modelo de capacidades e maturidade para defesa cibernética

    OpenAIRE

    Sylvio Andre Diogo Silva

    2011-01-01

    Uma implantação eficaz de defesa cibernética requer o desenvolvimento de esforços coordenados nas seguintes capacidades-chave: detecção de ataques, mecanismos de defesa, monitoramento de situação, comando e controle, aprimoramento de estratégias e táticas e desenvolvimento seguro de sistemas. A dissertação apresenta um modelo de capacidades para defesa cibernética. A partir das seis capacidades-chave, foi identificado um modelo com capacidades essenciais para a defesa cibernética. O modelo de...

  2. Frequência de mola hidatiforme em tecidos obtidos por curetagem uterina Frequency of hydatidiform mole in tissue obtained by curettage

    Directory of Open Access Journals (Sweden)

    Andressa Biscaro

    2012-06-01

    Full Text Available OBJETIVO: Determinar a frequência de mola hidatiforme em tecidos obtidos por curetagem uterina. MÉTODOS: Estudo transversal, prospectivo e descritivo que incluiu pacientes submetidas à curetagem uterina por diagnóstico de aborto ou mola hidatiforme cujo material obtido foi encaminhado para exame anatomopatológico. Foram excluídas aquelas que não aceitaram participar da pesquisa, recusando-se a assinar o Termo de Consentimento Informado Livre e Esclarecido. Foram analisadas as seguintes variáveis: achados anatomopatológicos, idade, raça/cor, número de gestações e abortos prévios, idade gestacional no momento do diagnóstico, níveis séricos quantitativos da fração beta da gonadotrofina coriônica humana e achados ultrassonográficos. As variáveis foram empregadas para a verificação com o diagnóstico histológico, considerado o padrão-ouro. Os dados foram armazenados e analisados no software Microsoft Excel® e no programa Epi-Info, versão 6.0 (STATCALC e os resultados apresentados como frequência (porcentagem ou média±desvio padrão. Para a associação entre variáveis qualitativas foi usado o teste do χ², e admitiu-se significância estatística quando pPURPOSE: To determine the frequency of hydatiform mole in tissues obtained by curettage. METHODS: A cross-sectional, prospective and descriptive conducted on patients who underwent curretage due to a diagnosis of abortion or hydatiform mole whose material was sent for pathological examination. We excluded women who did not accept to participate and refused to sign the free informed consent form. We studied the following variables: pathological findings, age, race, number of pregnancies and previous abortions, gestational age at diagnosis, quantitative serum beta fraction of human chorionic gonadotropin and ultrasound findings. The data were compared to the to histological diagnosis, considered to be the gold standard. Data were stored and analyzed in Microsoft Excel

  3. Perfil docente para alumnos/as con altas capacidades

    Directory of Open Access Journals (Sweden)

    María Leonor Conejeros-Solar

    2013-01-01

    Full Text Available El presente artículo tiene por objeto determinar un perfil de competencias docentes construido desde la percepción de estudiantes con altas capacidades pertenecientes a un programa universitario para talentos académicos. Se utiliza una metodología cualitativa con una estrategia documental de carácter retrospectivo. Los resultados indican que los estudiantes realizan una evaluación profunda sobre la docencia, incluyendo elementos pedagógicos como flexibilidad, ritmo e integración teoría-práctica. Las percepciones de los estudiantes, poco incorporadas en discusiones relativas a la enseñanza, permiten repensar y delinear un perfil de las competencias docentes relevadas para un trabajo pedagógico efectivo con talentosos en el aula.

  4. Un estudio exploratorio de capacidades emocionales en adultos mayores

    Directory of Open Access Journals (Sweden)

    Zoe S. Bello Dávila

    2012-01-01

    Full Text Available Abstract The study of the emotional world of the elderly is a fundamental requisite for guaranteeing the well-being and health of this group. The objective of this research paper was to characterize a group of elderly people according to their motional capabilities. The group consisted of 122 elderly persons: 107 female, 15 male. All attendants participated in a “Círculo de Abuelos” (Circle of Grandparents. The study was descriptive, it sought to gather information about the responses of older adults in situations of emotional content by completing a questionnaire. The results provided a profile of capacities where areas of strength and weakness are clearly distinguished. Selfconfidence and the possibility of fulfilling projects are among the strengths while the weaknesses are found in interpersonal or intrapersonal managing of emotions. These results have led to a better understanding of the emotional world of the elderly and guide future educational activities. Resumen El estudio del mundo emocional de los adultos mayores es un requisito fundamental para garantizar el estado de bienestar y salud de los mismos. El presente artículo de investigación se fijó como objetivo caracterizar a un grupo de ancianos, en función de sus capacidades emocionales. Los participantes fueron 122 ancianos, en concreto 107 mujeres y 15 hombres, que asisten a un “Círculo de Abuelos”. El estudio fue de tipo descriptivo, pues pretendió recoger información acerca de las respuestas de los adultos mayores ante situaciones de contenido emocional que se exploran por medio de un cuestionario elaborado al efecto. Los resultados ofrecen un perfil de capacidades en que la autoconfianza y la posibilidad de elaborar proyectos se erigen como fortalezas, mientras que las debilidades se expresan en las dificultades para el manejo emocional tanto a nivel intra como interpersonal. Estos resultados han permitido lograr una mejor comprensión del mundo emocional del

  5. Resolving the role of actoymyosin contractility in cell microrheology.

    Directory of Open Access Journals (Sweden)

    Christopher M Hale

    2009-09-01

    Full Text Available Einstein's original description of Brownian motion established a direct relationship between thermally-excited random forces and the transport properties of a submicron particle in a viscous liquid. Recent work based on reconstituted actin filament networks suggests that nonthermal forces driven by the motor protein myosin II can induce large non-equilibrium fluctuations that dominate the motion of particles in cytoskeletal networks. Here, using high-resolution particle tracking, we find that thermal forces, not myosin-induced fluctuating forces, drive the motion of submicron particles embedded in the cytoskeleton of living cells. These results resolve the roles of myosin II and contractile actomyosin structures in the motion of nanoparticles lodged in the cytoplasm, reveal the biphasic mechanical architecture of adherent cells-stiff contractile stress fibers interdigitating in a network at the cell cortex and a soft actin meshwork in the body of the cell, validate the method of particle tracking-microrheology, and reconcile seemingly disparate atomic force microscopy (AFM and particle-tracking microrheology measurements of living cells.

  6. Atomic Structure of Type VI Contractile Sheath from Pseudomonas aeruginosa.

    Science.gov (United States)

    Salih, Osman; He, Shaoda; Planamente, Sara; Stach, Lasse; MacDonald, James T; Manoli, Eleni; Scheres, Sjors H W; Filloux, Alain; Freemont, Paul S

    2018-02-06

    Pseudomonas aeruginosa has three type VI secretion systems (T6SSs), H1-, H2-, and H3-T6SS, each belonging to a distinct group. The two T6SS components, TssB/VipA and TssC/VipB, assemble to form tubules that conserve structural/functional homology with tail sheaths of contractile bacteriophages and pyocins. Here, we used cryoelectron microscopy to solve the structure of the H1-T6SS P. aeruginosa TssB1C1 sheath at 3.3 Å resolution. Our structure allowed us to resolve some features of the T6SS sheath that were not resolved in the Vibrio cholerae VipAB and Francisella tularensis IglAB structures. Comparison with sheath structures from other contractile machines, including T4 phage and R-type pyocins, provides a better understanding of how these systems have conserved similar functions/mechanisms despite evolution. We used the P. aeruginosa R2 pyocin as a structural template to build an atomic model of the TssB1C1 sheath in its extended conformation, allowing us to propose a coiled-spring-like mechanism for T6SS sheath contraction. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Effect of serotonin on small intestinal contractility in healthy volunteers

    DEFF Research Database (Denmark)

    Hansen, M.B.; Arif, F.; Gregersen, H.

    2008-01-01

    The physiological significance of serotonin released into the intestinal lumen for the regulation of motility is unknown in humans. The aim of this study was to evaluate the effect of serotonin infused into the lumen of the gastric antrum, duodenum or the jejunum, on antro-duodeno-jejunal contrac......The physiological significance of serotonin released into the intestinal lumen for the regulation of motility is unknown in humans. The aim of this study was to evaluate the effect of serotonin infused into the lumen of the gastric antrum, duodenum or the jejunum, on antro......-duodeno-jejunal contractility in healthy human volunteers. Manometric recordings were obtained and the effects of either a standard meal, continuous intravenous infusion of serotonin (20 nmol/kg/min) or intraluminal bolus infusions of graded doses of serotonin (2.5, 25 or 250 nmol) were compared. In addition, platelet......-depleted plasma levels of serotonin, blood pressure, heart rate and electrocardiogram were evaluated. All subjects showed similar results. Intravenous serotonin increased migrating motor complex phase In frequency 3-fold and migrating velocity 2-fold. Intraluminal infusion of serotonin did not change contractile...

  8. Evaluation of a second uterine flushing on embryo recovery in Nelore cows / Avaliação de uma segunda lavagem uterina sobre a recuperacão de embriões em vacas Nelore

    Directory of Open Access Journals (Sweden)

    Marcelo Marcondes Seneda

    2008-08-01

    Full Text Available The objective of the present study was to evaluate the effect of a second uterine flushing on number of recovered embryos. Cyclic Nelore cows (n= were used as donors. Animals were kept under grazing conditions in a farm at Mamborê, Paraná state. Cows were submitted to two sessions of multiple ovulation 80 days apart. At a random stage of estrus cycle (Day 0 donors received an intravaginal device with 1.9 g of progesterone (CIDR; Pfizer; Brasil. Twenty four hours later (Day 1 cows were injected with 2.5 mg/ IM of Estradiol Benzoate (Estrogin, Farmavet, Brasil. Between Day 5 and Day 9, donors received decreasing doses of 250 UI of FSH (Pluset; Calier, Brasil. On Days 7 and cows received 25 mg/ IM of dinoprost (Lutalyse, Pfizer, Brasil and progesterone implants were removed 12 hs later. Artificial insemination was performed 12 and 24 hours after estrus detection. The first embryo recovery was performed 7 days after AI with the Foley catheter positioned in the uterine body. A total of 1.000 mL of PBS (Embriocare, Cultilab, Brasil was used in a closed system of uterine flushing, with a 70 µm filter. Recovered uterine fluid was evaluated under a stereomicroscope (SMZ 654, Nikon, Japan and embryos were classified accord to IETS (1998. Twenty four hours later, the second uterine flushing was performed following the same procedure. Results were analyzed by t-Student test (p O objetivo do presente experimento foi verificar a viabilidade de uma segunda lavagem uterina sobre a recuperação de embriões. Doadoras cíclicas da raça Nelore (n= foram mantidas a pasto no município de Mamborê, Estado do Paraná. Os animais foram submetidos a tratamentos de superovulação com intervalo de 80 dias. Em um dia aleatório do ciclo estral (Dia 0 as doadoras receberam um dispositivo intravaginal contendo 1,9 g de progesterona (CIDR; Pfizer, Brasil. Vinte e quatro horas após (Dia 1 administrou-se , mg de benzoato de Estradiol (Estrogin; Farmavet, Brasil por via

  9. Papel da Histerossonografia no Estudo da Cavidade Uterina em Pacientes com Sangramento Uterino Anormal Role of Sonohysterography in the Evaluation of the Uterine Cavity in Patients with Abnormal Uterine Bleeding

    Directory of Open Access Journals (Sweden)

    Angélica Lemos Debs Diniz

    2000-06-01

    Full Text Available Objetivo: determinar o papel da histerossonografia na avaliação das anormalidades da cavidade uterina, em pacientes com sangramento uterino anormal, selecionadas previamente pela ultra-sonografia transvaginal. Métodos: foram selecionadas 48 pacientes na menacme e pós-menopausa, portadoras de sangramento uterino anormal e anormalidades da cavidade uterina, diagnosticadas inicialmente pela ultra-sonografia transvaginal. Todas as pacientes se submeteram à histerossonografia e, posteriormente, aos métodos "padrão ouro", a histeroscopia e/ou histerectomia. As histerossonografias foram avaliadas por dois diferentes médicos e os diagnósticos confrontados. Resultados: a histerossonografia mostrou ter alta sensibilidade e especificidade no diagnóstico das patologias benignas da cavidade uterina. Na presença de pólipo a sensibilidade e a especificidade do método foram, respectivamente, de 100 e 97%, seguido do mioma submucoso cuja sensibilidade e especificidade foram, respectivamente, de 83 e 100%. Já na hiperplasia endometrial e no endométrio normal a sensibilidade e especificidade foram de 100%. Diagnosticamos 33 casos de pólipos, 13 casos de miomas submucosos, quatro casos de hiperplasia endometrial e três casos normais na análise dos métodos "padrão ouro". Houve alta correlação entre os diagnósticos dados pelos dois examinadores. Conclusões: a histerossonografia mostrou ser um exame reprodutível, com alta sensibilidade e especificidade no diagnóstico das patologias benignas da cavidade uterina em pacientes com sangramento uterino anormal.Purpose: to determine the role of sonohysterography in the evaluation of abnormalities in the uterine cavity in patients presenting abnormal uterine bleeding, who had previously been selected by transvaginal ultrasonography. Methods: forty-eight patients presenting abnormal uterine bleeding and changes in the uterine cavity seen by transvaginal ultrasonography were selected, and they were in

  10. Prevenção do Nascimento Prematuro: Importância da Monitorização das Contrações Uterinas Prevention of Preterm Birth: Role of Uterine Contraction Monitoring

    Directory of Open Access Journals (Sweden)

    Eduardo Sérgio Borges da Fonseca

    1999-10-01

    Full Text Available Objetivo: avaliar a relação entre alterações das contrações uterinas e parto prematuro. Metodologia: entre fevereiro de 1996 e junho de 1998, 73 gestantes com risco para o parto prematuro foram submetidas à monitorização externa das contrações uterinas, da 24ª à 34ª semana de gestação, duas vezes por semana, durante 60 minutos. O teste foi considerado positivo quando as contrações uterinas apresentavam freqüência maior ou igual a 4 contrações/hora antes da 30ª semana e a 6 contrações/hora após esta data. Resultado: foram excluídas da análise 17 pacientes (23,28% por apresentarem patologias obstétricas ou evolução desfavorável para os resultados finais. Das 56 gestantes restantes, a incidência de partos prematuros espontâneos foi de 23,21% (13/56. A freqüência média das contrações uterinas foi significativamente maior no grupo que evoluiu para o parto prematuro. O método revelou uma sensibilidade de 69,23%, uma especificidade de 86,04% e valores preditivos positivo e negativo de 60% e 90,24%, respectivamente. Conclusão: o teste negativo está associado a baixo risco de nascimento prematuro. Contudo, diante do teste positivo, torna-se necessária a associação com outros marcadores do parto prematuro para melhor identificar pacientes com risco elevado.Purpose: to evaluate the relationship between uterine contractions and premature delivery. Methods: between February 1996 and July 1998, 73 high risk pregnant women for preterm delivery, between the 24th and 34th weeks of gestation, were submitted to uterine contraction monitoring with tokodynamometers for 1 hour twice a week. The positive test was the presence of 4 contractions/h before the 30th week of gestation, and after this time, 6 contractions/h. Result: of 73 women, 17 patients (23.28% were excluded from the final analysis because they presented obstetric problems or unfavorable development for the final result. The rate of preterm delivery was 21

  11. Contractility of the guinea pig bladder measured in situ and in vitro

    NARCIS (Netherlands)

    J.M. Groen (Jan); R. van Mastrigt (Ron); J.L.H.R. Bosch (Ruud)

    1994-01-01

    textabstractTo study the relative importance of neurogenic factors in detrusor contractility and to relate a total bladder in vitro contractility model to a previously described bladder wall strip model, active intravesical pressure values were compared in situ and in vitro in eight male guinea

  12. Free radicals in hypoxic rat diaphragm contractility: no role for xanthine oxidase.

    NARCIS (Netherlands)

    Heunks, L.M.A.; Machiels, H.A.; Abreu, R.A. de; Zhu, X.; Heijden, E. van der; Dekhuijzen, P.N.R.

    2001-01-01

    Recent evidence indicates that hypoxia enhances the generation of oxidants. Little is known about the role of free radicals in contractility of the rat diaphragm during hypoxia. We hypothesized that antioxidants improve contractility of the hypoxic rat diaphragm and that xanthine oxidase (XO) is an

  13. Effects of ageing on single muscle fibre contractile function following short-term immobilisation

    DEFF Research Database (Denmark)

    Hvid, Lars G; Ørtenblad, Niels; Aagaard, Per

    2011-01-01

    Very little attention has been given to the combined effect of healthy ageing and short-term disuse on the contractile function of human single muscle fibres. Therefore, the present study investigated the effects of 2 weeks of lower limb cast immobilisation (i.e. disuse) on selected contractile...

  14. Transient impairments in single muscle fibre contractile function after prolonged cycling in elite endurance athletes

    DEFF Research Database (Denmark)

    Hvid, L G; Gejl, Kasper Degn; Bech, R D

    2013-01-01

    Prolonged muscle activity impairs whole-muscle performance and function. However, little is known about the effects of prolonged muscle activity on the contractile function of human single muscle fibres. The purpose of this study was to investigate the effects of prolonged exercise and subsequent...... recovery on the contractile function of single muscle fibres obtained from elite athletes....

  15. Detecting cardiac contractile activity in the early mouse embryo using multiple modalities

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    Chiann-mun eChen

    2015-01-01

    Full Text Available The heart is one of the first organs to develop during mammalian embryogenesis. In the mouse, it starts to form shortly after gastrulation, and is derived primarily from embryonic mesoderm. The embryonic heart is unique in having to perform a mechanical contractile function while undergoing complex morphogenetic remodelling. Approaches to imaging the morphogenesis and contractile activity of the developing heart are important in understanding not only how this remodelling is controlled but also the origin of congenital heart defects. Here, we describe approaches for visualising contractile activity in the developing mouse embryo, using brightfield time lapse microscopy and confocal microscopy of calcium transients. We describe an algorithm for enhancing this image data and quantifying contractile activity from it. Finally we describe how atomic force microscopy can be used to record contractile activity prior to it being microscopically visible.

  16. Capacidades y recursos que influyen en las empresas femeninas

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    Diana M. Escandón Barbosa

    2011-06-01

    Full Text Available Este artículo tiene como propósito tratar de conocer las principales capacidades y los recursos que influyen en las empresas femeninas. Para lo cual se analizan los datos recopilados por GEM Colombia 2009, pero filtrando la base de datos y permitiendo utilizar solo lo relacionado con el género femenino. Dentro de los resultados se logró obtener un modelo consistente con la literatura sobre competitividad, destacando los recursos humanos, la innovación y la internacionalización. Sin embargo, no hay evidencia que explique cada una de estas variables por género y mucho menos la relación con competitividad. Para lo cual, los autores plantean una primera aproximación y que puede generar tendencias investigativas al respecto. La metodología aplicada en este artículo, es un sistema de ecuaciones estructurales, mediante el paquete estadístico SPSS Amos 18, que permite generar un esquema de relaciones entre las variables, y, acercarse a las tendencias de modelos en las explicaciones de las ciencias sociales.

  17. Crisis de la capacidad regulativa y flexibilidad del Derecho

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    Ángeles Galiana Saura

    2014-02-01

    Full Text Available RESUMEN. El contexto actual de nuestro ordenamiento jurídico es calificado en muchas ocasiones como de “crisis del Derecho” o de debilitamiento de la capacidad regulativa del Derecho, donde tiene lugar un aumento de la relevancia de los instrumentos jurídicos “flexibles”, también denominados en ocasiones “soft”, capaces de adaptarse a contextos diversos y cambiantes. El presente artículo realiza una aproximación al fenómeno del soft law, a través de algunas de sus manifestaciones en nuestro ordenamiento jurídico y los efectos que comporta su inclusión en el mismo, especialmente respecto al principio de seguridad jurídica. ABSTRACT. The present context of our legal system is often described as “crisis of Law” or as the weakening of the regulatory capacity of the law, where the relevance of “flexible” juridical means, so called because of their capacity to adapt to diverse and changing environments and which are sometimes referred as “soft” too, is increasing. This article makes an approach to the phenomenon of soft law through some of its manifestations and the effects that come from its inclusion in our legal order, specially in regard to the principle of legal certainty.

  18. Crisis de la capacidad regulativa y flexibilidad del Derecho

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    Ángeles Galiana Saura

    2010-12-01

    Full Text Available RESUMEN. El contexto actual de nuestro ordenamiento jurídico es calificado en muchas ocasiones como de “crisis del Derecho” o de debilitamiento de la capacidad regulativa del Derecho, donde tiene lugar un aumento de la relevancia de los instrumentos jurídicos “flexibles”, también denominados en ocasiones “soft”, capaces de adaptarse a contextos diversos y cambiantes. El presente artículo realiza una aproximación al fenómeno del soft law, a través de algunas de sus manifestaciones en nuestro ordenamiento jurídico y los efectos que comporta su inclusión en el mismo, especialmente respecto al principio de seguridad jurídica. ABSTRACT. The present context of our legal system is often described as “crisis of Law” or as the weakening of the regulatory capacity of the law, where the relevance of “flexible” juridical means, so called because of their capacity to adapt to diverse and changing environments and which are sometimes referred as “soft” too, is increasing. This article makes an approach to the phenomenon of soft law through some of its manifestations and the effects that come from its inclusion in our legal order, specially in regard to the principle of legal certainty.

  19. Capacidade funcional, morbidades e qualidade de vida de idosos

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    Darlene Mara dos Santos Tavares

    2012-01-01

    Full Text Available La investigación tiene como objetivo describir el perfil demográfico, la capacidad funcional y la morbilidad de los ancianos, y verificar la calidad de vida relacionado con el número de incapacidad funcional y la morbilidad. Estudio transversal analítico llevado a cabo con 2.142 personas mayores. Los datos fueron recolectados en el hogar con un instrumento estructurado. El análisis se realizó distribución de frecuencias, F-test de ANOVA y Bonferroni (p<0,05. La mayoría eran mujeres, años, casado, años de escolaridad y los ingresos de un salario mínimo. Predominaron los adultos mayores discapacidades funcionales relacionadas con la movilidad y morbilidad, los problemas de visión más frecuente y la columna vertebral y la hipertensión. Las puntuaciones más altas de calidad de vida para las relaciones sociales y el funcionamiento de los sentidos y el más bajo para su desarrollo físico y la autonomía. El mayor número de incapacidad funcional y la morbilidad asociadas con bajas puntuaciones en la calidad de vida.

  20. Cardiac contractility, central haemodynamics and blood pressure regulation during semistarvation

    DEFF Research Database (Denmark)

    Stokholm, K H; Breum, L; Astrup, A

    1991-01-01

    pressure (BP) declined. The fall in BP was caused by the reduction in cardiac output as the total peripheral resistance was unchanged. Finally, the decline in total blood volume was not significant. These findings together with a reduction in heart rate indicated that a reduced sympathetic tone via......Eight obese patients were studied before and after 2 weeks of treatment by a very-low-calorie diet (VLCD). Cardiac output and central blood volume (pulmonary blood volume and left atrial volume) were determined by indicator dilution (125I-albumin) and radionuclide angiocardiography (first pass...... and equilibrium technique by [99Tcm]red blood cells). Cardiac output decreased concomitantly with the reduction in oxygen uptake as the calculated systemic arteriovenous difference of oxygen was unaltered. There were no significant decreases in left ventricular contractility indices, i.e. the ejection fraction...

  1. Matrix elasticity regulates the optimal cardiac myocyte shape for contractility

    Science.gov (United States)

    McCain, Megan L.; Yuan, Hongyan; Pasqualini, Francesco S.; Campbell, Patrick H.

    2014-01-01

    Concentric hypertrophy is characterized by ventricular wall thickening, fibrosis, and decreased myocyte length-to-width aspect ratio. Ventricular thickening is considered compensatory because it reduces wall stress, but the functional consequences of cell shape remodeling in this pathological setting are unknown. We hypothesized that decreases in myocyte aspect ratio allow myocytes to maximize contractility when the extracellular matrix becomes stiffer due to conditions such as fibrosis. To test this, we engineered neonatal rat ventricular myocytes into rectangles mimicking the 2-D profiles of healthy and hypertrophied myocytes on hydrogels with moderate (13 kPa) and high (90 kPa) elastic moduli. Actin alignment was unaffected by matrix elasticity, but sarcomere content was typically higher on stiff gels. Microtubule polymerization was higher on stiff gels, implying increased intracellular elastic modulus. On moderate gels, myocytes with moderate aspect ratios (∼7:1) generated the most peak systolic work compared with other cell shapes. However, on stiffer gels, low aspect ratios (∼2:1) generated the most peak systolic work. To compare the relative contributions of intracellular vs. extracellular elasticity to contractility, we developed an analytical model and used our experimental data to fit unknown parameters. Our model predicted that matrix elasticity dominates over intracellular elasticity, suggesting that the extracellular matrix may potentially be a more effective therapeutic target than microtubules. Our data and model suggest that myocytes with lower aspect ratios have a functional advantage when the elasticity of the extracellular matrix decreases due to conditions such as fibrosis, highlighting the role of the extracellular matrix in cardiac disease. PMID:24682394

  2. Calidad de vida urbana y capacidad de pago de los hogares bogotanos 2011

    OpenAIRE

    Bonilla, Ricardo; Fresneda, Óscar; Gallo, Ignacio; Martínez, Jorge; Moreno, Álvaro; Muñoz, Manuel; Pachón, Nelson; Torres, Hugo; Villamizar, Óscar

    2014-01-01

    Antecedentes. Entre los años 2002 y 2006, el CID desarrolló un estudio de capacidad de pago de los hogares bogotanos con el objetivo específico de analizar si la estratificación de los hogares utilizada como la base para definir las tarifas de los servicios públicos domiciliarios se correspondía con la capacidad de pago de los hogares. Así se realizó la “Encuesta de capacidad de pago de los hogares bogotanos”, la cual fue aplicada por el CID en 2004. A partir del análi...

  3. Progesterone Metabolites Produced by Cytochrome P450 3A Modulate Uterine Contractility in a Murine Model

    Science.gov (United States)

    Patil, Avinash S.; Swamy, Geeta K.; Murtha, Amy P.; Heine, R. Phillips; Zheng, Xiaomei; Grotegut, Chad A.

    2015-01-01

    Objective: We seek to characterize the effect of progesterone metabolites on spontaneous and oxytocin-induced uterine contractility. Study Design: Spontaneous contractility was studied in mouse uterine horns after treatment with progesterone, 2α-hydroxyprogesterone, 6β-hydroxyprogesterone (6β-OHP), 16α-hydroxyprogesterone (16α-OHP), or 17-hydroxyprogesterone caproate (17-OHPC) at 10−9 to 10−6 mol/L. Uterine horns were exposed to progestins (10−6 mol/L), followed by increasing concentrations of oxytocin (1-100 nmol/L) to study oxytocin-induced contractility. Contraction parameters were compared for each progestin and matched vehicle control using repeated measures 2-way analysis of variance. In vitro metabolism of progesterone by recombinant cytochrome P450 3A (CYP3A) microsomes (3A5, 3A5, and 3A7) identified major metabolites. Results: Oxytocin-induced contractile frequency was decreased by 16α-OHP (P = .03) and increased by 6β-OHP (P = .05). Progesterone and 17-OHPC decreased oxytocin-induced contractile force (P = .02 and P = .04, respectively) and frequency (P = .02 and P = .03, respectively). Only progesterone decreased spontaneous contractile force (P = .02). Production of 16α-OHP and 6β-OHP metabolites were confirmed in all CYP3A isoforms tested. Conclusion: Progesterone metabolites produced by maternal or fetal CYP3A enzymes influence uterine contractility. PMID:26037300

  4. Capacidade embriogênica da cultivar IAS-5 de soja

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    Di Mauro Antonio Orlando

    2001-01-01

    Full Text Available O objetivo deste trabalho foi estudar o controle genético da formação de embriões somáticos da cultivar IAS-5 de soja. O experimento foi conduzido em casa de vegetação, cultivando-se quatro plantas por vaso, sob fotoperíodo de 14 horas e temperatura em torno de 28°C. Efetuaram-se cruzamentos entre os parentais não-embriogênicos (cultivares IAC-6, Paraná e IAC-15 e embriogênico (cultivar IAS-5 e retrocruzamentos para obtenção das gerações F1, F2,RC1P1 e RC1P2. Cotilédones imaturos, com 4-6 mm de comprimento, derivados dos parentais das gerações F1, F2, RC1P1 e RC1P2 foram cultivados em placas de Petri contendo meio N10, por um período de 90 dias, em câmara de crescimento. Os embriões somáticos derivados da indução foram contados, e os números, usados para obtenção dos parâmetros genéticos. Os resultados obtidos mostraram que o caráter capacidade de produção de embriões somáticos da cultivar IAS-5 é de natureza quantitativa e controlado por, aproximadamente, 20 genes.

  5. Malformação arteriovenosa uterina após doença trofoblástica gestacional Uterine arteriovenous malformation after gestational trophoblastic disease

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    Paulo Belfort

    2006-02-01

    Full Text Available OBJETIVO: investigar a presença e resultados de malformações vasculares uterinas (MAVU após doença trofoblástica gestacional (DTG. MÉTODOS: estudo retrospectivo com inclusão de casos diagnosticados entre 1987 e 2004; 2764 pacientes após DTG foram acompanhadas anualmente com ultra-sonografia transvaginal e Doppler colorido no Centro de Neoplasia Trofoblástica Gestacional da Santa Casa da Misericórdia (Rio de Janeiro, RJ, Brasil. Sete pacientes tiveram diagnóstico final de MAVU baseado em análise ultra-sonográfica - índice de pulsatilidade (IP, índice de resistência (IR e velocidade sistólica máxima (VSM - e achados de imagens de ressonância nuclear magnética (RNM. Dosagens negativas de beta-hCG foram decisivas para estabelecer o diagnóstico diferencial com DTG recidivante. RESULTADOS: a incidência de MAVU após DTG foi 0,2% (7/2764. Achados ultra-sonográficos de MAVU: IP médio de 0,44±0,058 (extremos: 0,38-0,52; IR médio de 0,36±0,072 (extremos: 0,29-0,50; VSM média de 64,6±23,99 cm/s (extremos: 37-96. A imagem de RNM revelou útero aumentado, miométrio heterogêneo, espaços vasculares tortuosos e vasos parametriais com ectasia. A apresentação clínica mais comum foi hemorragia transvaginal, presente em 52,7% (4/7 dos casos. Tratamento farmacológico com 150 mg de acetato de medroxiprogesterona foi empregado para controlar a hemorragia, após a estabilização hemodinâmica. Permanecem as pacientes em seguimento, assintomáticas até hoje. Duas pacientes engravidaram com MAVU, com gestações e partos exitosos. CONCLUSÃO: presente sangramento transvaginal em pacientes com beta-hCG negativo e história de DTG, deve-se considerar a possibilidade de MAVU e solicitar avaliação ultra-sonográfica com dopplervelocimetria. O tratamento conservador é a melhor opção na maioria dos casos de MAVU pós-DTG.PURPOSE: to investigate the presence and outcome of uterinevascular malformations (UVAM after gestational

  6. Nova pipeta para inseminação intra-uterina em suínos New pipette for intrauterine insemination in pigs

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    Gustavo Nogueira Diehl

    2006-02-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho reprodutivo de 423 fêmeas suínas de ordem de parto 1 a 9 submetidas à inseminação intra-uterina (IAU, com um novo modelo de pipeta (T1 cuja extremidade não é fixada na cérvix ou uma pipeta de IAU modelo Verona® e que permite a fixação da sua extremidade em espiral na cérvix (T2. Para comparar as duas pipetas, foi considerado o grau de dificuldade para realização das inseminações, o tempo necessário para realizá-las, a presença de sangramento após a inseminação, a presença de refluxo no momento da inseminação, as taxas de retorno ao estro (TR, de prenhez (TPR e de parto ajustada (TPA, além do número de leitões nascidos (NT. As fêmeas de ambos os grupos foram inseminadas com doses de 1 bilhão de espermatozóides, em intervalos de 24 horas. A passagem do cateter de IAU através da cérvix foi possível em 95,9% das fêmeas, sem diferença entre os tratamentos (P>0,05. Em pelo menos uma das inseminações, foi observado sangue no cateter, após a realização da IAU, em 20,6% das fêmeas do T1 e 15,2% das fêmeas do T2 (P=0,14. O tempo médio necessário para realizar a inseminação foi de 2,1 minutos para o T1 e 2,3 minutos para o T2 (P=0,26. O percentual de fêmeas com refluxo de sêmen no momento da inseminação foi maior (P=0,01 no T1 (8,4% em comparação ao T2 (2,9%. Não houve diferença (P>0,05 nas variáveis TR (8,0 e 4,8%, TPR (93,4 e 96,2% e NT (12,4 e 12,7 leitões entre T1 e T2, respectivamente. A TPA do T1 (90,6% apresentou tendência (P=0,07 de ser inferior à do T2 (95,1%. No T1, as fêmeas primíparas apresentaram maior TR e menor TPA em comparação às pluríparas (PThe aim of this work was to evaluate the reproductive performance of 423 sows of 1 to 9 farrowings inseminated with two different intrauterine artificial insemination (IAU pipettes. The first group (T1 was formed by sows inseminated with a new pipette whose extremity was not fixed in the

  7. CAPACIDAD DE AGENCIA DE AUTOCUIDADO EN LAS PERSONAS ADULTAS QUE PADECEN ARTRITIS REUMATOIDE

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    Viriam Leiva Díaz

    2012-04-01

    Full Text Available El objetivo de la investigación consistió en analizar la capacidad de agencia de autocuidado que poseen laspersonas con diagnóstico de artritis reumatoide, quienes habitan en los cantones de Palmares y San Ramón. Se desarrolló una metodología de investigación cuantitativa de tipo descriptiva transversal. En cuanto a la población participante del estudio, estuvo conformada por 13 personas diagnosticadas con artritis reumatoide; respecto de los instrumentos utilizados para recolectar información, a los colaboradores se les aplicó el instrumento “Escala de apreciación de la capacidad de agencia de autocuidado”, propuesta por Dorothea Orem. Se determinó que los participantes poseen alta capacidad de agencia de autocuidado en las diferentes categorías, ya que únicamente se detectó baja capacidad de agencia de autocuidado en cuanto a interacción social (2 personas, y respecto del consumo insuficiente de alimentos (5 personas. La escala ASA permite a la Enfermera (o determinar la capacidad de agencia de autocuidado, de forma oportuna y eficaz. Además, permitió a las investigadoras observar un panorama general de las necesidades de autocuidado de la población participante y constatar que esta presenta alta capacidad de agencia de autocuidado.

  8. Estudo dopplerfluxométrico das artérias uterinas antes e após inserção do DIU Color doppler flow analysis of the uterine arteries before and after DIU insertion

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Martins de Souza

    2004-06-01

    Full Text Available OBJETIVO: averiguar se ocorrem alterações nos parâmetros da dopplervelocimetria em usuárias do dispositivo intra-uterino (DIU T cobre 380, por meio do estudo das artérias uterinas antes e depois da inserção do DIU em mulheres lactantes e não lactantes. MÉTODOS: ensaio clínico prospectivo, analítico, com 100 pacientes, em que avaliamos à dopplervelocimetria: índice de resistência (IR, índice de pulsatilidade (IP e relação sístole/diástole (SD. As pacientes selecionadas foram submetidas à avaliação pré-inserção do DIU e a novos exames pós-inserção, realizados com 30 dias (um ciclo e com 90 dias (três ciclos. RESULTADOS: os valores obtidos nas artérias uterinas no grupo antes da inserção do DIU foram de 0,9 para o IR, de 2,4 para o IP e de 10,0 para a relação SD. Os valores 30 dias após a inserção do DIU foram de 0,9 para o IR, de 2,5 para o IP e de 10,7 para a relação SD. Após três ciclos aferimos um valor de 0,9 para o IR, de 2,5 para o IP e de 10,7 para a relação SD. A comparação dos resultados obtidos antes e depois da inserção do DIU mostrou valor p de 0,51 para o IR, de 0,37 para o IP e de 0,51 para a relação SD, demonstrando que após a inserção, não houve modificações significativas na dopplervelocimetria. CONCLUSÕES: o uso do DIU T cobre 380 não tem efeito nos índices de dopplervelocimetria das artérias uterinas tanto em pacientes amamentando ou não.OBJECTIVE: to observe if there is any alteration in the Dopplervelocimetry of the uterine arteries of nursing and not nursing women after the insertion of the copper T 380 intrauterine device (IUD. METHODS: prospective, analytical, self-paired clinical assay, with 100 patients in whom we evaluated the color doppler flow: resistance index (RI, pulsative index (PI and systole/diastole (SD ratio. Nursing and not nursing women were assessed before IUD insertion as well as 30 days (one cycle and 90 days (three cycles after the insertion

  9. Quantifying esophagogastric junction contractility with a novel HRM topographic metric, the EGJ-Contractile Integral: normative values and preliminary evaluation in PPI non-responders.

    Science.gov (United States)

    Nicodème, F; Pipa-Muniz, M; Khanna, K; Kahrilas, P J; Pandolfino, J E

    2014-03-01

    Despite its obvious pathophysiological relevance, the clinical utility of measures of esophagogastric junction (EGJ) contractility is unsubstantiated. High-resolution manometry (HRM) may improve upon this with its inherent ability to integrate the magnitude of contractility over time and length of the EGJ. This study aimed to develop a novel HRM metric summarizing EGJ contractility and test its ability distinguish among subgroups of proton pump inhibitor non-responders (PPI-NRs). 75 normal controls and 88 PPI-NRs were studied. All underwent HRM. PPI-NRs underwent pH-impedance monitoring on PPI therapy scored in terms of acid exposure, number of reflux events, and reflux-symptom correlation and grouped as meeting all criteria, some criteria, or no criteria of abnormality. Control HRM studies were used to establish normal values for candidate EGJ contractility metrics, which were then compared in their ability to differentiate among PPI-NR subgroups. The EGJ contractile integral (EGJ-CI), a metric integrating contractility across the EGJ for three respiratory cycles, best distinguished the All Criteria PPI-NR subgroup from controls and other PPI-NR subgroups. Normal values (median, [IQR]) for this measure were 39 mmHg-cm [25-55 mmHg-cm]. The correlation between the EGJ-CI and a previously proposed metric, the lower esophageal sphincter-pressure integral, that used a fixed 10 s time frame and an atmospheric as opposed to gastric pressure reference was weak. Among HRM metrics tested, the EGJ-CI was best in distinguishing PPI-NRs meeting all criteria of abnormality on pH-impedance testing. Future prospective studies are required to explore its utility in management of broader groups of gastroesophageal reflux disease patients. © 2013 John Wiley & Sons Ltd.

  10. Adipose-derived stem cells inhibit the contractile myofibroblast in Dupuytren's disease.

    NARCIS (Netherlands)

    Verhoekx, J.S.; Mudera, V.; Walbeehm, E.T.; Hovius, S.E.

    2013-01-01

    BACKGROUND: In an attempt to provide minimally invasive treatment for Dupuytren's disease, percutaneous disruption of the affected tissue followed by lipografting is being tested. Contractile myofibroblasts drive this fibroproliferative disorder, whereas stem cells have recently been implicated in

  11. Considerations for Contractile Electroactive Polymeric Materials and Actuators

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Lenore; Erickson, Carl J.; Meixler, Lewis D.; Ascione, George; Gentile, Charles A.; Tilson, Charles; Bernasek, Stephen L.; Abelev, Esta

    2009-06-16

    Ras Labs produces electroactive polymer (EAP) based materials and actuators that bend, swell, ripple and now contract (new development) with low electric input. This is an important attribute because of the ability of contraction to produce life-like motion. The mechanism of contraction is not well understood. Radionuclide-labeled experiments were conducted to follow the movement of electrolytes and water in these EAPs when activated. Extreme temperature experiments were performed on the contractile EAPs with very favorable results. One of the biggest challenges in developing these actuators, however, is the electrode-EAP interface because of the pronounced movement of the EAP. Plasma treatments of metallic electrodes were investigated in order to improve the attachment of the embedded electrodes to the EAP material. Surface analysis, adhesive testing, and mechanical testing were conducted to test metal surfaces and metal-polymer interfaces. The nitrogen plasma treatment of titanium produced a strong metal-polymer interface; however, oxygen plasma treatment of both stainless steel and titanium produced even stronger metal-polymer interfaces. Plasma treatment of the electrodes allows for the embedded electrodes and the EAP material of the actuator to work and move as a unit, with no detachment, by significantly improving the metal-polymer interface.

  12. Mechanism of action of ethanol on heart contractility

    International Nuclear Information System (INIS)

    Oquendo-Muriente, I.; De Mello, W.C.

    1986-01-01

    Ethanol depresses heart contractility. To investigate the mechanism of the negative inotropic action of ethanol, rat ventricular strips were dissected and mounted vertically in a transparent chamber. The preparation was superfused initially with normal oxygenated Tyrode solution (32.5 0 C) and electrically stimulated (1 Hz). After 1 hour of equilibration, contractures were elicited by exposing the muscle strips to high K + (100 mM) solution. Studies on the influence of (Ca 2+ ) 0 on K + contractures showed that the first rapid component of the contracture (58 mg/sec - S.E. +/- 8; n = 8) was greatly dependent upon (Ca 2+ ) 0 while the second slow component (20 mg/sec - S.E. +/- 5; n = 8) was slightly altered. The addition of ethanol (400 mg/100 ml) to high K solution abolished the fast component and reduced the amplitude of the second phase of K contractures. Similar results were obtained with verapamil (10 -5 M). These results, as well as studies on the effect of the drug on 45 Ca fluxes support the view that ethanol decreases the permeability of the heart cell membrane to Ca

  13. Mechanism of action of ethanol on heart contractility

    Energy Technology Data Exchange (ETDEWEB)

    Oquendo-Muriente, I.; De Mello, W.C.

    1986-03-05

    Ethanol depresses heart contractility. To investigate the mechanism of the negative inotropic action of ethanol, rat ventricular strips were dissected and mounted vertically in a transparent chamber. The preparation was superfused initially with normal oxygenated Tyrode solution (32.5/sup 0/C) and electrically stimulated (1 Hz). After 1 hour of equilibration, contractures were elicited by exposing the muscle strips to high K/sup +/ (100 mM) solution. Studies on the influence of (Ca/sup 2 +/)/sub 0/ on K/sup +/ contractures showed that the first rapid component of the contracture (58 mg/sec - S.E. +/- 8; n = 8) was greatly dependent upon (Ca/sup 2 +/)/sub 0/ while the second slow component (20 mg/sec - S.E. +/- 5; n = 8) was slightly altered. The addition of ethanol (400 mg/100 ml) to high K solution abolished the fast component and reduced the amplitude of the second phase of K contractures. Similar results were obtained with verapamil (10/sup -5/ M). These results, as well as studies on the effect of the drug on /sup 45/Ca fluxes support the view that ethanol decreases the permeability of the heart cell membrane to Ca.

  14. Contractile Force of Human Extraocular Muscle: A Theoretical Analysis

    Directory of Open Access Journals (Sweden)

    Hongmei Guo

    2016-01-01

    Full Text Available Aim. The length-contractile force relationships of six human extraocular muscles (EOMs in primary innervations should be determined during eye movement modeling and surgery of clinical EOMs. This study aims to investigate these relationships. Method. The proposal is based on the assumption that six EOMs have similar constitutive relationships, with the eye suspended in the primary position. The constitutive relationships of EOMs are obtained by optimizing from previous experimental data and the theory of mechanical equilibrium using traditional model. Further, simulate the existing experiment of resistance force, and then compare the simulated results with the existing experimental results. Finally, the mechanical constitutive relationships of EOMs are obtained. Results. The results show that the simulated resistance forces from the other four EOMs except for the horizontal recti well agree with previous experimental results. Conclusion. The mechanical constitutive relationships of six EOMs in primary innervations are obtained, and the rationality of the constitutive relationships is verified. Whereafter, the active stress-strain relationships of the six EOMs in the primary innervations are obtained. The research results can improve the eye movement model to predict the surgical amounts of EOMs before EOM surgery more precisely.

  15. Postextrasystolic potentiation and contractile reserve: requirements and restrictions.

    Science.gov (United States)

    Lust, R M; Lutherer, L O; Gardner, M E; Cooper, M W

    1982-12-01

    These studies were conducted to examine the basic characteristics of postextrasystolic potentiation (PESP) and the relationship of loading effects to PESP. Measurements of left ventricular (LV) and aortic pressures, the rate of pressure rise, and echocardiographically determined LV dimensions were made in anesthetized open-chest dogs. The hearts were paced, and timed extrasystoles were introduced that were followed by postextrasystoles (PES). PES's were elicited after an interval equal to either a full compensatory pause or a time when the diastolic properties of the LV could not be distinguished from control (isolength). Potentiation of contraction for the PES's introduced after an isolength pause was dependent on both the heart rate and the extrasystolic interval, whereas the PES's that occurred after a full pause showed no dependence on either of these intervals. PESP elicited during the isolength period was not dependent on either preload and afterload. It is concluded that PESP depends on the combination of heart rate and extrasystolic and postextrasystolic intervals. Further, PESP may be inaccurate in assessing contractile reserve unless the heart rate and extrasystolic interval are known and the PES is introduced after an isolength pause.

  16. Considerations for Contractile Electroactive Polymeric Materials and Actuators

    International Nuclear Information System (INIS)

    Rasmussen, L.; Erickson, Carl J.; Meixler, Lewis D.; Ascione, G.; Gentile, Charles A.; Tilson, C.; Bernasek, Stephen L.; Abelev, E.

    2009-01-01

    Ras Labs produces electroactive polymer (EAP) based materials and actuators that bend, swell, ripple and now contract (new development) with low electric input. This is an important attribute because of the ability of contraction to produce life-like motion. The mechanism of contraction is not well understood. Radionuclide-labeled experiments were conducted to follow the movement of electrolytes and water in these EAPs when activated. Extreme temperature experiments were performed on the contractile EAPs with very favorable results. One of the biggest challenges in developing these actuators, however, is the electrode-EAP interface because of the pronounced movement of the EAP. Plasma treatments of metallic electrodes were investigated in order to improve the attachment of the embedded electrodes to the EAP material. Surface analysis, adhesive testing, and mechanical testing were conducted to test metal surfaces and metal-polymer interfaces. The nitrogen plasma treatment of titanium produced a strong metal-polymer interface; however, oxygen plasma treatment of both stainless steel and titanium produced even stronger metal-polymer interfaces. Plasma treatment of the electrodes allows for the embedded electrodes and the EAP material of the actuator to work and move as a unit, with no detachment, by significantly improving the metal-polymer interface

  17. Cellular Architecture Regulates Collective Calcium Signaling and Cell Contractility.

    Directory of Open Access Journals (Sweden)

    Jian Sun

    2016-05-01

    Full Text Available A key feature of multicellular systems is the ability of cells to function collectively in response to external stimuli. However, the mechanisms of intercellular cell signaling and their functional implications in diverse vascular structures are poorly understood. Using a combination of computational modeling and plasma lithography micropatterning, we investigate the roles of structural arrangement of endothelial cells in collective calcium signaling and cell contractility. Under histamine stimulation, endothelial cells in self-assembled and microengineered networks, but not individual cells and monolayers, exhibit calcium oscillations. Micropatterning, pharmacological inhibition, and computational modeling reveal that the calcium oscillation depends on the number of neighboring cells coupled via gap junctional intercellular communication, providing a mechanistic basis of the architecture-dependent calcium signaling. Furthermore, the calcium oscillation attenuates the histamine-induced cytoskeletal reorganization and cell contraction, resulting in differential cell responses in an architecture-dependent manner. Taken together, our results suggest that endothelial cells can sense and respond to chemical stimuli according to the vascular architecture via collective calcium signaling.

  18. Modeling the dispersion effects of contractile fibers in smooth muscles

    Science.gov (United States)

    Murtada, Sae-Il; Kroon, Martin; Holzapfel, Gerhard A.

    2010-12-01

    Micro-structurally based models for smooth muscle contraction are crucial for a better understanding of pathological conditions such as atherosclerosis, incontinence and asthma. It is meaningful that models consider the underlying mechanical structure and the biochemical activation. Hence, a simple mechanochemical model is proposed that includes the dispersion of the orientation of smooth muscle myofilaments and that is capable to capture available experimental data on smooth muscle contraction. This allows a refined study of the effects of myofilament dispersion on the smooth muscle contraction. A classical biochemical model is used to describe the cross-bridge interactions with the thin filament in smooth muscles in which calcium-dependent myosin phosphorylation is the only regulatory mechanism. A novel mechanical model considers the dispersion of the contractile fiber orientations in smooth muscle cells by means of a strain-energy function in terms of one dispersion parameter. All model parameters have a biophysical meaning and may be estimated through comparisons with experimental data. The contraction of the middle layer of a carotid artery is studied numerically. Using a tube the relationships between the internal pressure and the stretches are investigated as functions of the dispersion parameter, which implies a strong influence of the orientation of smooth muscle myofilaments on the contraction response. It is straightforward to implement this model in a finite element code to better analyze more complex boundary-value problems.

  19. Modifying influence of incorporated 137Cs upon the mechanisms of adrenergic control over contractile myucard function

    International Nuclear Information System (INIS)

    Lobanok, L.M.; Bulanova, K.Ya.; Gerasimovich, N.V.; Sineleva, M.V.; Milyutin, A.A.

    1994-01-01

    Incorporated 137 Cs (absorbed dose of 0.26 Gy) causes decrease of myocard's contractile function and intropic response to β-adrenagonists effect, isoproterenol-stimulated adenylate cyclase activity and β-adrenoreceptors affinity. Adrenergic effects, mediated by α-adrenergic structures on heart contractile function, on the contrary, become stronger, that is due to the increase of the receptors' dencity on sarcolemma surface

  20. Reliability of contractile properties of the knee extensor muscles in individuals with post-polio syndrome.

    Directory of Open Access Journals (Sweden)

    Eric L Voorn

    Full Text Available To assess the reliability of contractile properties of the knee extensor muscles in 23 individuals with post-polio syndrome (PPS and 18 age-matched healthy individuals.Contractile properties of the knee extensors were assessed from repeated electrically evoked contractions on 2 separate days, with the use of a fixed dynamometer. Reliability was determined for fatigue resistance, rate of torque development (MRTD, and early and late relaxation time (RT50 and RT25, using the intraclass correlation coefficient (ICC and standard error of measurement (SEM, expressed as % of the mean.In both groups, reliability for fatigue resistance was good, with high ICCs (>0.90 and small SEM values (PPS: 7.1%, healthy individuals: 7.0%. Reliability for contractile speed indices varied, with the best values found for RT50 (ICCs>0.82, SEM values <2.8%. We found no systematic differences between test and retest occasions, except for RT50 in healthy subjects (p = 0.016.In PPS and healthy individuals, the reliability of fatigue resistance, as obtained from electrically evoked contractions is high. The reliability of contractile speed is only moderate, except for RT50 in PPS, demonstrating high reliability.This was the first study to examine the reliability of electrically evoked contractile properties in individuals with PPS. Our results demonstrate its potential to study mechanisms underlying muscle fatigue in PPS and to evaluate changes in contractile properties over time in response to interventions or from natural course.

  1. Thick filament length and isoform composition determine self-organized contractile units in actomyosin bundles.

    Science.gov (United States)

    Thoresen, Todd; Lenz, Martin; Gardel, Margaret L

    2013-02-05

    Diverse myosin II isoforms regulate contractility of actomyosin bundles in disparate physiological processes by variations in both motor mechanochemistry and the extent to which motors are clustered into thick filaments. Although the role of mechanochemistry is well appreciated, the extent to which thick filament length regulates actomyosin contractility is unknown. Here, we study the contractility of minimal actomyosin bundles formed in vitro by mixtures of F-actin and thick filaments of nonmuscle, smooth, and skeletal muscle myosin isoforms with varied length. Diverse myosin II isoforms guide the self-organization of distinct contractile units within in vitro bundles with shortening rates similar to those of in vivo myofibrils and stress fibers. The tendency to form contractile units increases with the thick filament length, resulting in a bundle shortening rate proportional to the length of constituent myosin thick filament. We develop a model that describes our data, providing a framework in which to understand how diverse myosin II isoforms regulate the contractile behaviors of disordered actomyosin bundles found in muscle and nonmuscle cells. These experiments provide insight into physiological processes that use dynamic regulation of thick filament length, such as smooth muscle contraction. Copyright © 2013 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  2. A comparative study of contractility of the heart ventricle in some ectothermic vertebrates

    Directory of Open Access Journals (Sweden)

    Sergey Kharin

    2009-07-01

    Full Text Available The purpose of this study was to analyze contractility of the heart ventricle in selected reptilian and amphibian species having the same ventricular excitation pattern. Systolic time intervals and indices of contractility of the heart ventricle were measured in anaesthetized frogs, snakes, and tortoises by use of polycardiography. The electromechanical delay was significantly shorter in tortoises compared with the other two species. The isovolumetric contraction time in frogs was approximately twofold longer than in reptiles. The pre-ejection period was the longest in frogs and the shortest in tortoises, whereas snakes were intermediate. The ejection time was slightly longer in tortoises compared with the other two species. The greatest isovolumetric contraction index and the smallest myocardial tension index corresponded to the frog and tortoise heart ventricle, respectively. The intrasystolic index in tortoises was significantly greater than in frogs, whereas quite similar to that in snakes. The frog ventricle had lower contractility compared with the reptilian one. Although ventricular contractility tended to be lower in snakes compared with tortoises, this difference was not statistically significant. Possible causes for these differences are discussed. We suppose a large variety in ventricular contractility among amphibian and reptilian species having the same ventricular activation pattern. This variety may be conditioned by heart anatomy, intracardiac shunting, lifestyles, and habitats. It can only be hypothesized that on the average, ventricular contractility is higher in reptiles compared with amphibians and in chelonians compared with snakes.

  3. Bienestar psicológico en personas con alta capacidad intelectual

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    Pedro Ramiro Olivier

    2016-12-01

    Full Text Available El bienestar psicológico en las personas de alta capacidad intelectual ha sido motivo de controversia en la literatura especializada. En ocasiones se ha considerado que estas personas son más proclives a un desajuste psicológico, mientras que otras veces los resultados han sido poco concluyentes. En el presente trabajo se ha estudiado el bienestar psicológico en personas de altas capacidades intelectuales, administrando la Escala de Bienestar Psicológico a 28 participantes de edades comprendidas entre los 22 y 34 años de edad. Fueron divididos en 2 grupos, uno de altas capacidades y otro de inteligencia estándar. El grupo de altas capacidades había sido identificado como tal 25 años atrás, cuando tenían una edad comprendida entre los 5 y 13 años, utilizando el modelo de los 3 anillos de Renzulli. Los resultados indicaron la inexistencia de diferencias significativas entre los participantes de altas capacidades e inteligencia estándar en las diferentes subescalas de bienestar personal, a excepción de la subescala de bienestar material.

  4. The Functional Lumen Imaging Probe Detects Esophageal Contractility not Observed with Manometry in Patients with Achalasia

    Science.gov (United States)

    Carlson, Dustin A.; Lin, Zhiyue; Kahrilas, Peter J.; Sternbach, Joel; Donnan, Erica N.; Friesen, Laurel; Listernick, Zoe; Mogni, Benjamin; Pandolfino, John E.

    2015-01-01

    Background & Aims The functional lumen imaging probe (FLIP) could improve characterization of achalasia subtypes by detecting non-occlusive esophageal contractions not observed with standard manometry. We aimed to evaluate for esophageal contractions during volumetric distention in patients with achalasia using FLIP topography. Methods Fifty one treatment-naïve patients with achalasia, defined and sub-classified by high-resolution esophageal pressure topography, and 10 asymptomatic individuals (controls) were evaluated with the FLIP during endoscopy. During stepwise distension, simultaneous intra-bag pressures and 16 channels of cross-sectional areas were measured; data were exported to software that generated FLIP topography plots. Esophageal contractility was identified by noting periods of reduced luminal diameter. Esophageal contractions were further characterized by propagation direction, repetitiveness, and based on whether they were occluding or non-occluding. Results Esophageal contractility was detected in all 10 controls: 8/10 had repetitive, antegrade, contractions and 9/10 had occluding contractions. Contractility was detected in 27% (4/15) of patients with type I achalasia and 65% (18/26, including 9 with occluding contractions) of patients with type II achalasia. Contractility was detected in all 10 patients with type III achalasia; 8 of these patients had a pattern of contractility not observed in controls (repetitive, retrograde contractions). Conclusions Esophageal contractility not observed with manometry can be detected in patients with achalasia using FLIP topography. The presence and patterns of contractility detected with FLIP topography may represent variations in pathophysiology, such as mechanisms of pan-esophageal pressurization in patients with type II achalasia. These findings could have implications for additional sub-classification to supplement prediction of the achalasia disease course. PMID:26278501

  5. Effects of endothelin, calcium channel blockade and EDRF inhibition on the contractility of human uteroplacental arteries.

    Science.gov (United States)

    Fried, G; Liu, Y A

    1994-08-01

    In order to examine the possibility that endothelin might be important in the regulation of placental blood flow, human uteroplacental vessels were superfused in vitro to study the contractile effect of endothelin as compared with a known strong contractor of placental blood vessels, serotonin (5-HT). The contractile responses were compared in the presence and absence of calcium channel blocking agents, as well as in the presence of L-NMA, an inhibitor of EDRF/nitric oxide. Endothelin (ET, 10(-10)-10(-6) M) and 5-HT (10(-8)-10(-4) M) induced contractions in the vessels. Maximal contractions in the presence of endothelin were elicited at 10(-7) M, whereas 5-HT elicited maximal contractions at 10(-5) M. At 10(-7) M, ET was more potent than 5-HT. The calcium-channel blocking agents nifedipine, diltiazem and NiCl2 relaxed the vessels by 5-15% from baseline. The contractile response to ET in the presence of nifedipine or diltiazem was reduced by 55 and 67%, respectively. The response of 5-HT in the presence of nifedipine was reduced by 58%. The contractile response to 5-HT as well as ET in the presence of both nifedipine and NiCl2 was not significantly lower than in the presence of nifedipine only. The EDRF-inhibiting agent L-NMA caused a small contractile response at concentrations of 10(-6)-10(-5) M. ET as well as 5-HT added after pretreatment with L-NMA produced a larger contractile response than ET or 5-HT alone. The results show that ET has a strong contractile effect on placental blood vessels at concentrations likely to occur during labor and delivery. The mechanism whereby ET as well as 5-HT contracts placental vessel smooth muscle appears to partly involve nifedipine- and diltiazem-sensitive calcium channels, but almost half of the response depends on mobilization of calcium through other means.

  6. La doble cara de la capacidad empresarial: una alternativa a la noción popular

    Directory of Open Access Journals (Sweden)

    Bögenhold , Dieter

    2003-06-01

    Full Text Available La capacidad empresarial es un tema estratégico en los estudios de los procesos que llevan a la prosperidad y a la creación de empleos. Pese a ello, el concepto no está aún bien definido. Este artículo estudia los supuestos centrales y cuestiona lo que muchos contemporáneos dan por supuesto. El artículo muestra la necesidad de definir la capacidad empresarial. La discusión reciente debe explicar el fenómeno, a veces contradictorio, del rápido crecimiento de las grandes empresas y las nuevas microempresas de empleados por cuenta propia que no tienen posibilidades ni intenciones de crecer. Las políticas económicas deben especificar a qué se refieren cuando hablan de capacidad empresarial

  7. Un modelo educativo de adaptación curricular en alumnos de altas capacidades

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    Celestino RODRÍGUEZ

    2010-01-01

    Full Text Available En base a la legislación educativa española vigente, las altas capacidades se incluyen en el marco de las necesidades educativas específicas de apoyo educativo. En el presente estudio ejemplificamos una propuesta de adaptación curricular individual para alumnos con altas capacidades, que pretende promover el desarrollo equilibrado de los objetivos de aprendizaje propuestos en su programación de aula. Todo ello, a través de una descripción por pasos del proceso, partiendo de una evaluación previa de las altas capacidades, una planificación de la intervención educativa, una propuesta educativa concreta (ejemplificada en el área de Lengua castellana y el desarrollo de programas complementarios.

  8. Efeito do sulfato de magnésio sobre o índice de pulsatilidade das artérias uterinas, umbilical e cerebral média fetal de acordo com a persistência da incisura protodiastólica da artéria uterina na pré-eclâmpsia grave Effect of magnesium sulfate on pulsatility index of uterine, umbilical and fetal middle cerebral arteries according to the persistence of bilateral diastolic notch of uterine arteries in patients with severe preeclampsia

    Directory of Open Access Journals (Sweden)

    Alex Sandro Rolland Souza

    2009-02-01

    Full Text Available OBJETIVO: avaliar o efeito do sulfato de magnésio sobre o índice de pulsatilidade (IP das artérias uterinas, umbilicais e cerebral média fetal, de acordo com a persistência ou não da incisura protodiastólica bilateral das artérias uterinas na pré-eclâmpsia grave. MÉTODOS: foi desenvolvido um estudo do tipo coorte, incluindo 40 gestantes com pré-eclâmpsia grave, das quais 23 apresentavam incisura protodiastólica bilateral e 17, incisura ausente/unilateral. As pacientes foram submetidas a doplervelocimetria antes e depois de 20 minutos da administração intravenosa de 6 g do sulfato de magnésio. O exame foi realizado com a paciente em posição semi-Fowler, obtendo-se os sonogramas durante a inatividade fetal, em períodos de apneia e ausência de contrações uterinas. Todos os exames foram realizados por dois pesquisadores, considerando a média como resultado final. A comparação dos IP antes e depois do sulfato de magnésio em cada grupo foi realizada pelo teste de Wilcoxon. A diferença das duas medidas (antes e depois do sulfato de magnésio foi comparada entre os grupos (incisura bilateral e incisura ausente/unilateral utilizando-se o teste de Mann-Whitney. RESULTADOS: houve um aumento significativo da frequência cardíaca materna e uma diminuição da pressão arterial materna e da mediana dos IP das duas artérias uterinas e da artéria cerebral média fetal depois da utilização do sulfato de magnésio em ambos os grupos. Houve redução significativa do IP da artéria uterina esquerda e da artéria umbilical apenas no grupo com incisura protodiastólica unilateral/ausente. No entanto, não foram encontradas diferenças significativas em relação ao IP da artéria uterina direita e relação umbilical/cerebral antes e depois do sulfato de magnésio em cada grupo. Não se encontrou diferença entre os grupos, antes e depois do sulfato de magnésio, para nenhum dos desfechos estudados. CONCLUSÕES: após a administra

  9. 17 alpha-hydroxyprogesterone caproate vehicle, castor oil, enhances the contractile effect of oxytocin in human myometrium in pregnancy.

    Science.gov (United States)

    O'Sullivan, Michael D; Hehir, Mark P; O'Brien, Yvonne M; Morrison, John J

    2010-05-01

    The possibility exists that the vehicle for 17-alpha-hydroxyprogesterone caproate, castor oil, exerts an effect on human uterine contractility. The aim of this study was to evaluate its effects on contractility of myometrial preparations that were obtained during pregnancy. Myometrial strips were suspended under isometric conditions. Contractility was induced with oxytocin. Strips were incubated in castor oil or physiologic salt solution and suspended for a further oxytocin challenge. Contractile integrals were compared between both groups. Strips that were exposed to castor oil demonstrated increased contractile activity that was elicited by oxytocin (mean contractility value, 165.53%+/-17.03%; n=8; P=.004), compared with control strips (mean contractility value, 72.57%+/-7.48%; n=8; P=.003). There was a significant increase in contractile activity of the castor oil-exposed strips, compared with those that were exposed to physiologic salt solution (n=8; Pcastor oil results in enhanced oxytocin-induced contractility. Copyright (c) 2010 Mosby, Inc. All rights reserved.

  10. The role of voltage-gated potassium channels in the regulation of mouse uterine contractility

    Directory of Open Access Journals (Sweden)

    Abel Peter W

    2007-11-01

    Full Text Available Abstract Background Uterine smooth muscle cells exhibit ionic currents that appear to be important in the control of uterine contractility, but how these currents might produce the changes in contractile activity seen in pregnant myometrium has not been established. There are conflicting reports concerning the role of voltage-gated potassium (Kv channels and large-conductance, calcium-activated potassium (BK channels in the regulation of uterine contractility. In this study we provide molecular and functional evidence for a role for Kv channels in the regulation of spontaneous contractile activity in mouse myometrium, and also demonstrate a change in Kv channel regulation of contractility in pregnant mouse myometrium. Methods Functional assays which evaluated the effects of channel blockers and various contractile agonists were accomplished by quantifying contractility of isolated uterine smooth muscle obtained from nonpregnant mice as well as mice at various stages of pregnancy. Expression of Kv channel proteins in isolated uterine smooth muscle was evaluated by Western blots. Results The Kv channel blocker 4-aminopyridine (4-AP caused contractions in nonpregnant mouse myometrium (EC50 = 54 micromolar, maximal effect at 300 micromolar but this effect disappeared in pregnant mice; similarly, the Kv4.2/Kv4.3 blocker phrixotoxin-2 caused contractions in nonpregnant, but not pregnant, myometrium. Contractile responses to 4-AP were not dependent upon nerves, as neither tetrodotoxin nor storage of tissues at room temperature significantly altered these responses, nor were responses dependent upon the presence of the endometrium. Spontaneous contractions and contractions in response to 4-AP did not appear to be mediated by BK, as the BK channel-selective blockers iberiotoxin, verruculogen, or tetraethylammonium failed to affect either spontaneous contractions or 4-AP-elicited responses. A number of different Kv channel alpha subunit proteins were

  11. Impact of Cardiac Contractility during Cerebral Blood Flow in Ischemia

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    Silver, Brian

    2011-05-01

    Full Text Available Objective: In cerebral regions affected by ischemia, intrinsic vascular autoregulation is often lost. Blood flow delivery depends upon cardiac function and may be influenced by neuro-endocrine mediated myocardial suppression. Our objective is to evaluate the relation between ejection fraction (EF and transcranial doppler (TCD peak systolic velocities (PSV in patients with cerebral ischemic events.Methods: We conducted a retrospective cohort study from an existing TCD registry. We evaluated patients admitted within 24 hours of onset of a focal neurological deficit who had an echocardiogram and TCD performed within 72 hours of admission.Results: We identified 58 patients from March to October 2003. Eighty-one percent (n=47 had a hospital discharge diagnosis of ischemic stroke and 18.9% (n=11 had a diagnosis of transient ischemic attack. Fourteen patients had systolic dysfunction (EF50% compared to those with systolic dysfunction (EF<50% was as follows: middle cerebral artery 62.0 + 28.6 cm/s vs. 51.0 + 23.3 cm/s, p=0.11; anterior cerebral artery 52.1 + 21.6 cm/s vs. 45.9 + 22.7 cm/s, p=0.28; internal carotid artery 56.5 + 20.1 cm/s vs. 46.4 + 18.4 cm/s, p=0.04; ophthalmic artery 18.6 + 7.2 cm/s vs. 15.3 + 5.2 cm/s, p=0.11; vertebral artery 34.0 + 13.9 cm/s vs. 31.6 + 15.0 cm/s, p=0.44.Conclusion: Cerebral blood flow in the internal carotid artery territory appears to be higher in cerebral ischemia patients with preserved left ventricular contractility. Our study was unable to differentiate pre-existing cardiac dysfunction from neuro-endocrine mediated myocardial stunning. Future research is necessary to better understand heart-brain interactions in this setting and to further explore the underlying mechanisms and consequences of neuro-endocrine mediated cardiac dysfunction. [West J Emerg Med. 2011;12(2:227-232.

  12. Procesos de automatización cognitiva en alumnado con altas capacidades intelectuales

    Directory of Open Access Journals (Sweden)

    Juan Montero-Linares

    2013-05-01

    Full Text Available Proponemos desde el enfoque del procesamiento de la información, el estudio de características cognitivas que faciliten la identificación de las altas capacidades. A tal fin, elaboramos una tarea de habilidad de segmentación silábica que, a partir del modelo propuesto por Baddeley sobre la memoria de trabajo y la distinción entre procesos automáticos y controlados, nos permitiese comprobar las diferencias en cuanto a la capacidad de automatización de la información y si los indicadores propuestos en la misma, tenían suficiente poder clasificatorio o predictivo en la identificación de la alta capacidad intelectual. Participaron 480 niños y niñas de primero a cuarto de Educación Primaria. Se clasificaron, en función de su CI, en dos grupos: alumnado de altas capacidades y alumnado de capacidades medias. Se les administró una batería de pruebas entre las que se encontraba el test de habilidad de segmentación silábica, lo que permitió realizar su estandarización. Los resultados mostraron que los alumnos con CI superior a 130 fueron capaces de automatizar la segmentación de forma más eficiente que los de inteligencia media. La medición de los procesos automáticos a través del test de habilidad de segmentación silábica, permitió diferenciar a los participantes de altas capacidades de los que no lo eran.

  13. Effect of heat stress on contractility of tissue-engineered artificial skeletal muscle.

    Science.gov (United States)

    Takagi, Shunya; Nakamura, Tomohiro; Fujisato, Toshia

    2018-01-23

    The effects of heat stress on tissue like skeletal muscle have been widely studied. However, the mechanism responsible for the effect of heat stress is still unclear. A useful experimental tissue model is necessary because muscle function in cell culture may differ from native muscle and measuring its contractility is difficult. We previously reported three-dimensional tissue-engineered artificial skeletal muscle (TEM) that can be easily set in a measurement apparatus for quantitative evaluation of contractility. We have now applied TEM to the investigation of heat stress. We analyzed contractility immediately after thermal exposure at 39 °C for 24 or 48 h to evaluate the acute effects and after thermal exposure followed by normal culture to evaluate the aftereffects. Peak twitch contractile force and time-to-peak twitch were used as contractile parameters. Heat stress increased the TCF in the early stage (1 week) after normal culture; the TCF decreased temporarily in the middle to late stages (2-3 weeks). These results suggest that heat stress may affect both myoblast fusion and myotube differentiation in the early stage of TEM culture, but not myotube maturation in the late stage. The TCF increase rate with thermal exposure was significantly higher than that without thermal exposure. Although detailed analysis at the molecular level is necessary for further investigation, our artificial skeletal muscle may be a promising tool for heat stress investigation.

  14. Inhibition of isolated human myometrium contractility by minoxidil and reversal by glibenclamide.

    Science.gov (United States)

    Prabhakaran, S S; Dhanasekar, K R; Thomas, E; Jose, R; Peedicayil, J; Samuel, P

    2010-03-01

    This study investigated the ability of the antihypertensive drug minoxidil to inhibit potassium chloride (KCl)-induced contractility of the isolated human myometrium. Twelve strips of myometrium obtained from 12 patients who underwent hysterectomy were triggered to contract with 55 mM KCl before and after incubation with 3 concentrations (1, 3 and 10 microM) of minoxidil. The percent inhibition by minoxidil on the extent of contraction, and the area under the contractile curve of KCl-induced contraction of the myometrial strips was determined. Furthermore, the effect of 10 microM glibenclamide on the inhibition generated by 3 microM minoxidil on KCl-induced contractility was studied. It was found that minoxidil produced a concentration-dependent inhibition of KCl-induced contractility of the myometrium and that glibenclamide reversed this inhibitory effect. These results suggest that the inhibitory effect of minoxidil on isolated human myometrium contractility may prove useful in clinical conditions requiring relaxation of the myometrium. 2010 Prous Science, S.A.U. or its licensors. All rights reserved.

  15. Slack length reduces the contractile phenotype of the Swine carotid artery.

    Science.gov (United States)

    Rembold, Christopher M; Garvey, Sean M; Tejani, Ankit D

    2013-01-01

    Contraction is the primary function of adult arterial smooth muscle. However, in response to vessel injury or inflammation, arterial smooth muscle is able to phenotypically modulate from the contractile state to several 'synthetic' states characterized by proliferation, migration and/or increased cytokine secretion. We examined the effect of tissue length (L) on the phenotype of intact, isometrically held, initially contractile swine carotid artery tissues. Tissues were studied (1) without prolonged incubation at the optimal length for force generation (1.0 Lo, control), (2) with prolonged incubation for 17 h at 1.0 Lo, or (3) with prolonged incubation at slack length (0.6 Lo) for 16 h and then restoration to 1.0 Lo for 1 h. Prolonged incubation at 1.0 Lo minimally reduced the contractile force without substantially altering the mediators of contraction (crossbridge phosphorylation, shortening velocity or stimulated actin polymerization). Prolonged incubation of tissues at slack length (0.6 Lo), despite return of length to 1.0 Lo, substantially reduced contractile force, reduced crossbridge phosphorylation, nearly abolished crossbridge cycling (shortening velocity) and abolished stimulated actin polymerization. These data suggest that (1) slack length treatment significantly alters the contractile phenotype of arterial tissue, and (2) slack length treatment is a model to study acute phenotypic modulation of intact arterial smooth muscle. Copyright © 2013 S. Karger AG, Basel.

  16. ANTECEDENTES DEL USO DE LOS MEDIOS SOCIALES POR EL TURISTA: MOTIVACIÓN, OPORTUNIDAD Y CAPACIDAD

    Directory of Open Access Journals (Sweden)

    Desiderio Gutiérrez Taño

    2013-01-01

    Full Text Available El presente trabajo utiliza el modelo MOA para analizar en qué medida la motivación, la oportunidad y la capacidad de los usuarios son factores determinantes de las intenciones de uso de medios sociales en la organización y desarrollo de viajes turísticos. Las conclusiones del estudio revelan que las intenciones de uso de los medios sociales se ven afectadas por la motivación y las capacidades de los usuarios y, sin embargo, no se ven influenciadas por la oportunidad. A su vez, en las motivaciones influyen los beneficios funcionales y hedónicos, pero no los sociales.

  17. Proposta para estimar curva carga-recalque e capacidade de carga em estacas de madeira

    OpenAIRE

    Segundinho, Pedro Gutemberg de Alcântara; Miná, Alexandre José Soares; Dias, Antonio Alves; Regazzi, Adair José; Carreira, Marcelo Rodrigo

    2014-01-01

    Este trabalho teve como objetivo propor um método para estimar a curva carga-recalque e a capacidade de carga de estacas de madeira a partir do ajuste de equações de regressão não lineares utilizando o método de Gauss Newton modificado. Para isso, foram utilizados dados experimentais obtidos para 12 estacas de madeira, curvas carga-recalque durante a cravação e capacidade de carga determinada no ensaio de carregamento dinâmico, utilizando modelo teórico. Nesta pesquisa, realizada de forma pio...

  18. Estudio de la capacidad estabilizadora del peroné en fracturas de tibia de conejo

    OpenAIRE

    Fornells Miquel, P.; GÓMEZ BENITO, M.J.; García Aznar, J. M.; BEA CASCAROSA, J.A.

    2008-01-01

    El objetivo de este trabajo es estudiar la capacidad estabilizadora del peroné en fracturas de tibia. Si dicha capacidad es suficiente, sería posible evitar el uso de sistemas de fijación en los experimentos de laboratorio con este tipo de fracturas. Para comprobarlo se ha realizado una simulación computacional por elementos finitos de la tibia y el peroné de un conejo, con una fractura en el tercio medio superior de la diáfisis sin ningún elemento estabilizador. El conjunto ha sido sometido ...

  19. El mejoramiento de la capacidad para aprender a través de la lectura

    Directory of Open Access Journals (Sweden)

    Armando Morles

    1997-12-01

    Full Text Available El presente estudio discute la importancia de la instrucción en la capacidad para aprender el contenido de textos escritos. Al inicio se define el aprendizaje a través de la lectura para luego continuar con la identificación de los factores que condicionan este aprendizaje. Luego se suministra lineamientos para mejorar esa capacidad. Finalmente se aportan ideas acerca de cómo conducir el entrenamiento de los estudiantes, incluyendo las modalidades y su ubicación dentro del contexto educativo.

  20. Bienestar psicológico en personas con alta capacidad intelectual

    OpenAIRE

    Ramiro Olivier, Pedro; Navarro Guzmán, José I.; Menacho Jiménez, Inmaculada; López Sinoga, M. Mar; García Sedeño, Manuel A.

    2016-01-01

    El bienestar psicológico en las personas de alta capacidad intelectual ha sido motivo de controversia en la literatura especializada. En ocasiones se ha considerado que estas personas son más proclives a un desajuste psicológico, mientras que otras veces los resultados han sido poco concluyentes. En el presente trabajo se ha estudiado el bienestar psicológico en personas de altas capacidades intelectuales, administrando la Escala de Bienestar Psicológico a 28 participantes de edades comprendi...

  1. A Mobilização de Capacidades Dinâmicas na Lojas Renner

    OpenAIRE

    Adalberto Escalona Gonçalves Garcia; Luiz Paulo Bignetti

    2014-01-01

    O artigo tem como objetivo analisar a trajetória de uma das empresas varejistas de maior destaque no mercado brasileiro, através de um estudo longitudinal que enfatiza a mobilização de seus recursos e capacidades ao longo de 90 anos de história. Explorando o conceito de capacidades dinâmicas, descrevem-se as ações estratégicas empreendidas em momentos de crescimento e de crise. Para tanto, foram realizadas entrevistas em profundidade com dez tomadores de decisão que vivenciaram diferentes mom...

  2. Histomorfometria e histoquímica da tuba uterina e do útero de ratas púberes e pré-púberes induzidas ao hipertireoidismo Histomorphometry and histochemistry of the uterine tubes and uterus of puberal and prepuberal rats induced for hyperthyroidism

    Directory of Open Access Journals (Sweden)

    T.S. Oliveira

    2005-08-01

    Full Text Available Foram estudadas a histomorfometria e a atividade secretória das tubas uterinas e do útero de 38 ratas Wistar púberes, distribuídas em quatro grupos: (1 eutireóideo em proestro-estro, (2 hipertireóideo em proestro-estro, (3 eutireóideo em metaestro-diestro e (4 hipertireóideo em metaestro-diestro. Posteriormente, foram utilizadas outras 24 ratas Wistar pré-púberes, com 12 dias de idade, distribuídas em dois grupos: (1 hipertireóideo (n=12 e (2 eutireóideo (n=12. O útero e as tubas uterinas foram colhidos para avaliação histomorfométrica e histoquímica. A altura do epitélio da ampola, tanto no proestro-estro quanto no metaestro-diestro, elevou-se com a administração de tiroxina, tornando-se semelhante à do istmo. O hipertireoidismo aumentou a secreção PAS positiva e de mucossubstâncias ácidas do infundíbulo na fase estrogênica, igualando-a à do istmo. A parede uterina apresentou-se mais espessa na fase estrogênica, resultado da ação conjunta da tiroxina no endométrio e no miométrio. A atividade secretória e a composição do colágeno uterino não diferiram entre tratamentos. Nas ratas pré-púberes, o hipertireoidismo aumentou a espessura do miométrio e da parede uterina, mas não alterou a tuba uterina. O hipertireoidismo em ratas pré-púberes induz modificações significativas somente no útero; após a maturidade sexual, as modificações ocorrem no útero e na tuba uterina em intensidade variável e dependentes da fase do ciclo estral.The histomorphometry and the secretory activity of the uterine tubes and uterus of 38 puberal Wistar rats were studied. Rats were divided in four groups: (1 euthyroid in proestrus-estrus, (2 hyperthyroid in proestrus-estrus, (3 euthyroid in metestrus-diestrus and, (4 hyperthyroid in metestrus-diestrus. In other experiment, 24 prepuberal 12-day-old Wistar rats were divided in two groups: (1 hyperthyroid and (2 euthyroid. The uterus and the uterine tubes were collected for

  3. Contractile properties are disrupted in Becker muscular dystrophy, but not in limb girdle type 2I.

    Science.gov (United States)

    Løkken, Nicoline; Hedermann, Gitte; Thomsen, Carsten; Vissing, John

    2016-09-01

    We investigated whether a linear relationship between muscle strength and cross-sectional area (CSA) is preserved in calf muscles of patients with Becker muscular dystrophy (BMD, n = 14) and limb-girdle type 2I muscular dystrophy (LGMD2I, n = 11), before and after correcting for muscle fat infiltration. The Dixon magnetic resonance imaging technique was used to quantify fat and calculate a fat-free contractile CSA. Strength was assessed by dynamometry. Muscle strength/CSA relationships were significantly lower in patients versus controls. The strength/contractile-CSA relationship was still severely lowered in BMD, but was almost normalized in LGMD2I. Our findings suggest close to intact contractile properties in LGMD2I, which are severely disrupted in BMD. Ann Neurol 2016;80:466-471. © 2016 American Neurological Association.

  4. Suppression of guinea pig ileum induced contractility by plasma albumin of hibernators

    Science.gov (United States)

    Bruce, David S.; Ambler, Douglas L.; Henschel, Timothy M.; Oeltgen, Peter R.; Nilekani, Sita P.; Amstrup, Steven C.

    1992-01-01

    Previous studies suggest that hibernation may be regulated by internal opioids and that the putative “hibernation induction trigger” (HIT) may itself be an opioid. This study examined the effect of plasma albumin (known to bind HIT) on induced contractility of the guinea pig ileum muscle strip. Morphine (400 nM) depressed contractility and 100 nM naloxone restored it. Ten milligrams of lyophilized plasma albumin fractions from hibernating ground squirrels, woodchucks, black bears, and polar bears produced similar inhibition, with partial reversal by naloxone. Five hundredths mg of d-Ala2-d-Leu5-enkephalin (DADLE) also inhibited contractility and naloxone reversed it. Conclusions are that hibernating individuals of these species contain an HIT substance that is opioid in nature and summer animals do not; an endogenous opioid similar to leu-enkephalin may be the HIT compound or give rise to it.

  5. Mechanobiological induction of long-range contractility by diffusing biomolecules and size scaling in cell assemblies

    Science.gov (United States)

    Dasbiswas, K.; Alster, E.; Safran, S. A.

    2016-06-01

    Mechanobiological studies of cell assemblies have generally focused on cells that are, in principle, identical. Here we predict theoretically the effect on cells in culture of locally introduced biochemical signals that diffuse and locally induce cytoskeletal contractility which is initially small. In steady-state, both the concentration profile of the signaling molecule as well as the contractility profile of the cell assembly are inhomogeneous, with a characteristic length that can be of the order of the system size. The long-range nature of this state originates in the elastic interactions of contractile cells (similar to long-range “macroscopic modes” in non-living elastic inclusions) and the non-linear diffusion of the signaling molecules, here termed mechanogens. We suggest model experiments on cell assemblies on substrates that can test the theory as a prelude to its applicability in embryo development where spatial gradients of morphogens initiate cellular development.

  6. Plasticity of TOM complex assembly in skeletal muscle mitochondria in response to chronic contractile activity.

    Science.gov (United States)

    Joseph, Anna-Maria; Hood, David A

    2012-03-01

    We investigated the assembly of the TOM complex within skeletal muscle under conditions of chronic contractile activity-induced mitochondrial biogenesis. Tom40 import into mitochondria was increased by chronic contractile activity, as was its time-dependent assembly into the TOM complex. These changes coincided with contractile activity-induced augmentations in the expression of key protein import machinery components Tim17, Tim23, and Tom22, as well as the cytosolic chaperone Hsp90. These data indicate the adaptability of the TOM protein import complex and suggest a regulatory role for the assembly of this complex in exercise-induced mitochondrial biogenesis. Copyright © 2011 Elsevier B.V. and Mitochondria Research Society. All rights reserved. All rights reserved.

  7. Effects of minoxidil and nitroprusside on reflex increases in myocardial contractility.

    Science.gov (United States)

    Robie, N W

    1978-01-01

    1 The effects of nitroprusside and minoxidil on increases in myocardial contractility resulting from carotid artery occlusion were investigated in anaesthetized dogs. The results were compared with those produced by intravenous influsion of noradrenaline. 2 Nitroprusside and minoxidil attenuated the pressor responses produced by carotid artery occlusion. 3 Nitroprusside, but not minoxidil, attenuated the maximal myocardial contractility resulting from carotid occlusion. 4 The pressor and contractility responses to noradrenaline infusion were unaffected by either agent. 5 Nitroprusside failed to alter the myocardial responses produced by dimethylphenylpiperazinium. 6 These results, in conjunction with those of other investigators who have demonstrated that nitroprusside does not affect the release of noradrenaline from adrenergic neurons, suggest that nitroprusside may inhibit sympathetic nervous system reflex activity via an afferent and/or central component. PMID:620094

  8. Sex differences and the effects of ovariectomy on the β-adrenergic contractile response

    Science.gov (United States)

    McIntosh, Victoria J.; Chandrasekera, P. Charukeshi

    2011-01-01

    The presence of sex differences in myocardial β-adrenergic responsiveness is controversial, and limited studies have addressed the mechanism underlying these differences. Studies were performed using isolated perfused hearts from male, intact female and ovariectomized female mice to investigate sex differences and the effects of ovarian hormone withdrawal on β-adrenergic receptor function. Female hearts exhibited blunted contractile responses to the β-adrenergic receptor agonist isoproterenol (ISO) compared with males but not ovariectomized females. There were no sex differences in β1-adrenergic receptor gene or protein expression. To investigate the role of adenylyl cyclase, phosphodiesterase, and the cAMP-signaling cascade in generating sex differences in the β-adrenergic contractile response, dose-response studies were performed in isolated perfused male and female hearts using forskolin, 3-isobutyl-1-methylxanthine (IBMX), and 8-(4-chlorophenylthio)adenosine 3′,5′-cyclic monophosphate (CPT-cAMP). Males showed a modestly enhanced contractile response to forskolin at 300 nM and 5 μM compared with females, but there were no sex differences in the response to IBMX or CPT-cAMP. The role of the A1 adenosine receptor (A1AR) in antagonizing the β-adrenergic contractile response was investigated using both the A1AR agonist 2-chloro-N6-cyclopentyl-adenosine and A1AR knockout (KO) mice. Intact females showed an enhanced A1AR anti-adrenergic effect compared with males and ovariectomized females. The β-adrenergic contractile response was potentiated in both male and female A1ARKO hearts, with sex differences no longer present above 1 nM ISO. The β-adrenergic contractile response is greater in male hearts than females, and minor differences in the action of adenylyl cyclase or the A1AR may contribute to these sex differences. PMID:21685268

  9. Clinical Characteristics and Associated Systemic Diseases in Patients With Esophageal "Absent Contractility"-A Clinical Algorithm.

    Science.gov (United States)

    Laique, Sobia; Singh, Tavankit; Dornblaser, David; Gadre, Abhishek; Rangan, Vikram; Fass, Ronnie; Kirby, Donald; Chatterjee, Soumya; Gabbard, Scott

    2018-01-19

    This study was carried out to assess the clinical characteristics and associated systemic diseases seen in patients diagnosed with absent contractility as per the Chicago Classification version 3.0, allowing us to propose a diagnostic algorithm for their etiologic testing. The Chicago Classification version 3.0 has redefined major and minor esophageal motility disorders using high-resolution esophageal manometry. There is a dearth of publications based on research on absent contractility, which historically has been associated with myopathic processes such as systemic sclerosis (SSc). We conducted a retrospective, multicenter study. Data of patients diagnosed with absent contractility were pooled from Cleveland Clinic, Cleveland, OH (January 2006 to July 2016) and Metrohealth Medical Center, Cleveland, OH (July 2014 to July 2016) and included: age, gender, associated medical conditions, surgical history, medications, and specific antibody testing. A total of 207 patients, including 57 male individuals and 150 female individuals, with mean age of 56.1 and 60.0 years, respectively, were included. Disease distribution was as follows: SSc (diffuse or limited cutaneous) 132, overlap syndromes 7, systemic lupus erythematosus17, Sjögren syndrome 4, polymyositis 3, and dermatomyositis 3. Various other etiologies including gastroesophageal reflux disease, postradiation esophagitis, neuromuscular disorders, and surgical complications were seen in the remaining cohort. Most practitioners use the term "absent contractility" interchangeably with "scleroderma esophagus"; however, only 63% of patients with absent contractility had SSc. Overall, 20% had another systemic autoimmune rheumatologic disease and 16% had a nonrheumatologic etiology for absent contractility. Therefore, alternate diagnosis must be sought in these patients. We propose an algorithm for their etiologic evaluation.

  10. Accessory left atrial diverticulae: contractile properties depicted with 64-slice cine-cardiac CT.

    LENUS (Irish Health Repository)

    Killeen, Ronan P

    2012-02-01

    To assess the contractility of accessory left atrial appendages (LAAs) using multiphasic cardiac CT. We retrospectively analyzed the presence, location, size and contractile properties of accessory LAAs using multiphasic cardiac 64-slice CT in 102 consecutive patients (63 males, 39 females, mean age 57). Multiplanar reformats were used to create image planes in axial oblique, sagittal oblique and coronal oblique planes. For all appendages with an orifice diameter >or= 10 mm, axial and sagittal diameters and appendage volumes were recorded in atrial diastole and systole. Regression analysis was performed to assess which imaging appearances best predicted accessory appendage contractility. Twenty-three (23%) patients demonstrated an accessory LAA, all identified along the anterior LA wall. Dimensions for axial oblique (AOD) and sagittal oblique (SOD) diameters and sagittal oblique length (SOL) were 6.3-19, 3.4-20 and 5-21 mm, respectively. All appendages (>or=10 mm) demonstrated significant contraction during atrial systole (greatest diameter reduction was AOD [3.8 mm, 27%]). Significant correlations were noted between AOD-contraction and AOD (R = 0.57, P < 0.05) and SOD-contraction and AOD, SOD and SOL (R = 0.6, P < 0.05). Mean diverticulum volume in atrial diastole was 468.4 +\\/- 493 mm(3) and in systole was 171.2 +\\/- 122 mm(3), indicating a mean change in volume of 297.2 +\\/- 390 mm(3), P < 0.0001. Stepwise multiple regression analysis revealed SOL to be the strongest independent predictor of appendage contractility (R(2) = 0.86, P < 0.0001) followed by SOD (R(2) = 0.91, P < 0.0001). Accessory LAAs show significant contractile properties on cardiac CT. Those accessory LAAs with a large sagittal height or depth should be evaluated for contractile properties, and if present should be examined for ectopic activity during electrophysiological studies.

  11. Validation of an in vitro contractility assay using canine ventricular myocytes

    Energy Technology Data Exchange (ETDEWEB)

    Harmer, A.R., E-mail: alex.harmer@astrazeneca.com; Abi-Gerges, N.; Morton, M.J.; Pullen, G.F.; Valentin, J.P.; Pollard, C.E.

    2012-04-15

    Measurement of cardiac contractility is a logical part of pre-clinical safety assessment in a drug discovery project, particularly if a risk has been identified or is suspected based on the primary- or non-target pharmacology. However, there are limited validated assays available that can be used to screen several compounds in order to identify and eliminate inotropic liability from a chemical series. We have therefore sought to develop an in vitro model with sufficient throughput for this purpose. Dog ventricular myocytes were isolated using a collagenase perfusion technique and placed in a perfused recording chamber on the stage of a microscope at ∼ 36 °C. Myocytes were stimulated to contract at a pacing frequency of 1 Hz and a digital, cell geometry measurement system (IonOptix™) was used to measure sarcomere shortening in single myocytes. After perfusion with vehicle (0.1% DMSO), concentration–effect curves were constructed for each compound in 4–30 myocytes taken from 1 or 2 dog hearts. The validation test-set was 22 negative and 8 positive inotropes, and 21 inactive compounds, as defined by their effect in dog, cynolomolgous monkey or humans. By comparing the outcome of the assay to the known in vivo contractility effects, the assay sensitivity was 81%, specificity was 75%, and accuracy was 78%. With a throughput of 6–8 compounds/week from 1 cell isolation, this assay may be of value to drug discovery projects to screen for direct contractility effects and, if a hazard is identified, help identify inactive compounds. -- Highlights: ► Cardiac contractility is an important physiological function of the heart. ► Assessment of contractility is a logical part of pre-clinical drug safety testing. ► There are limited validated assays that predict effects of compounds on contractility. ► Using dog myocytes, we have developed an in vitro cardiac contractility assay. ► The assay predicted the in vivo contractility with a good level of accuracy.

  12. Spontaneous and α-adrenoceptor-induced contractility in human collecting lymphatic vessels require chloride

    DEFF Research Database (Denmark)

    Mohanakumar, Sheyanth; Majgaard, Jens; Telinius, Niklas

    2018-01-01

    - with the impermeant anion aspartate and inhibition of Cl- transport and channels with the clinical diuretics furosemide and bendroflumethiazide, as well as DIDS and NPPB. The molecular expression of calcium-activated chloride channels was investigated by RT-PCR and proteins localized using immunoreactivity....... Spontaneous and norepinephrine-induced contractility in human lymphatic vessels was highly abrogated after Cl- substitution with aspartate. 100‒300µM DIDS or NPPB inhibited spontaneous contractile behavior. Norepinephrine-stimulated tone was furthermore markedly abrogated by 200µM DIDS. Furosemide lowered...

  13. La evaluación psicopedagógica del alumnado con altas capacidades

    OpenAIRE

    Grau Rubio, Claudia

    2012-01-01

    Se describen los instrumentos de evaluación psicopedagógica aplicables al alumnado con altas capacidades. Instrumentos referidos al alumno, al contexto escolar, a las variables socio-familiares y la determinación de las necesidades educativas especiales.

  14. Qual capacidade crítica? Relendo Luc Boltanski à luz de Margaret Archer

    Directory of Open Access Journals (Sweden)

    Luiz Augusto Campos

    Full Text Available Resumo A chamada “sociologia da capacidade crítica” de Luc Boltanski vem se tornando um dos principais paradigmas teóricos de interpretação das relações sociais. Contrário ao modo como a sociologia crítica à la Bourdieu entende a reflexividade humana, Boltanski propõe tratar os indivíduos como seres reflexivos, plenamente capazes de julgar e criticar o mundo. No entanto, essa “capacidade crítica” funciona em sua sociologia mais como premissa teórica do que como objeto concreto de investigação. Diante disso, este texto argumenta que uma sociologia interessada na capacidade crítica dos sujeitos não pode apenas “supô-la”, deve constituí-la em objeto de estudo sociológico. Para tal, propõe-se reconceituar a capacidade crítica como competência reflexiva, no sentido dado à expressão pela socióloga inglesa Margaret Archer. O recurso às categorias de Archer não apenas ajuda a identificar os limites da sociologia de Boltanski, mas, sobretudo, permite ampliar o seu alcance.

  15. LA CAPACIDAD Y EL BIENESTAR SUBJETIVO COMO DIMENSIONES DE ESTUDIO DE LA CALIDAD DE VIDA

    Directory of Open Access Journals (Sweden)

    Beatriz Yasuko Arita Watanabe

    2005-06-01

    Full Text Available La Calidad de vida es trabajada científicamente como un constructo muy amplio que abarca diversos significados pero en lo general apunta a la búsqueda de la explicación de la buena vida, aquella que se disfruta, que satisface al que la vive y que le produce estados de felicidad. De allí que sea la persona, desde su percepción, la que evalúe su propia vida, sus capacidades y, en el propio contexto, desarrolle mecanismos de búsqueda del bienestar personal. El Plan de Naciones Unidas para el Desarrollo (PNUD, al hablar de desarrollo humano utiliza un índice combinado que considera niveles de ingreso y educación así como la esperanza de vida de la población. Son medidas objetivas de capacidad centradas en la búsqueda de mejoría de las condiciones de vida de las personas. En México, sus planteamientos son retomados por la Secretaría de Desarrollo Social (Sedesol en su programa “Oportunidades†haciendo referencia a la capacidad de las personas. Este programa no alcanza a definir indicadores que permitan trabajar el estudio de la apreciación de la vida, respecto a las capacidades percibidas y la evaluación del resultado de vida. El objetivo de la presente investigación va dirigido a integrar el estudio de los indicadores objetivos y subjetivos de la capacidad junto con los indicadores del bienestar subjetivo (satisfacción por la vida y felicidad sentida, para considerar a la capacidad y al bienestar subjetivo como dimensiones de explicación de la calidad de vida. La medición de los niveles de ingreso y educación junto con escalas de capacidad para enfrentar la vida y de bienestar subjetivo es utilizada para correr un análisis factorial exploratorio en una muestra representativa de la población adulta de la Zona Urbana de Culiacán, México. Palabras clave: Calidad

  16. La capacidad y el bienestar subjetivo como dimensiones de estudio de la calidad de vida

    Directory of Open Access Journals (Sweden)

    Beatriz Yasuko Arita Watanabe

    2005-01-01

    Full Text Available La Calidad de vida es trabajada científicamente como un constructo muy amplio que abarca diversos significados pero en lo general apunta a la búsqueda de la explicación de la buena vida, aquella que se disfruta, que satisface al que la vive y que le produce estados de felicidad. De allí que sea la persona, desde su percepción, la que evalúe su propia vida, sus capacidades y, en el propio contexto, desarrolle mecanismos de búsqueda del bienestar personal. El Plan de Naciones Unidas para el Desarrollo (PNUD, al hablar de desarrollo humano utiliza un índice combinado que considera niveles de ingreso y educación así como la esperanza de vida de la población. Son medidas objetivas de capacidad centradas en la búsqueda de mejoría de las condiciones de vida de las personas. En México, sus planteamientos son retomados por la Secretaría de Desarrollo Social (Sedesol en su programa “Oportunidades” haciendo referencia a la capacidad de las personas. Este programa no alcanza a definir indicadores que permitan trabajar el estudio de la apreciación de la vida, respecto a las capacidades percibidas y la evaluación del resultado de vida. El objetivo de la presente investigación va dirigido a integrar el estudio de los indicadores objetivos y subjetivos de la capacidad junto con los indicadores del bienestar subjetivo (satisfacción por la vida y felicidad sentida, para considerar a la capacidad y al bienestar subjetivo como dimensiones de explicación de la calidad de vida. La medición de los niveles de ingreso y educación junto con escalas de capacidad para enfrentar la vida y de bienestar subjetivo es utilizada para correr un análisis factorial exploratorio en una muestra representativa de la población adulta de la Zona Urbana de Culiacán, México.

  17. 2-Deoxyadenosine triphosphate restores the contractile function of cardiac myofibril from adult dogs with naturally occurring dilated cardiomyopathy

    OpenAIRE

    Cheng, Yuanhua; Hogarth, Kaley A.; O'Sullivan, M. Lynne; Regnier, Michael; Pyle, W. Glen

    2015-01-01

    1) First report to characterize and define the contractile kinetics and defects associated with naturally occurring dilated cardiomyopathy (DCM) in dogs. 2) Novel findings that dATP is able to reverse the contractile defects associated with naturally occurring canine DCM.

  18. Relação familiar da pessoa idosa com comprometimento da capacidade funcional

    Directory of Open Access Journals (Sweden)

    Luana Araújo dos Reis

    2015-01-01

    Full Text Available Objetivo: comprender la relación familiar de la persona adulta con comprometimiento de la capacidad funcional. Materiales y mé - todos: estudio exploratorio y descriptivo de abordaje cualitativo, fundamentado en el método de la historia oral, realizado con 15 adultos mayores asistidos por una unidad de salud de la familia, residentes con familiares y que presentaban comprometimiento de la capacidad funcional. Se recolectaron los datos en el período de marzo y abril del 2012, por medio de entrevistas en profundidad. Las categorías temáticas fueron: buena relación familiar, cambios en la relación familiar, sintiéndose un estorbo para la familia, sintiéndose abandonado por la familia. Resultado: el estudio ha revelado que las personas mayores con comprometimiento de la capacidad funcional vivencian sentimientos diversos que van desde la alegría porque son respetadas y tienen sus necesidades atendidas, hasta la tristeza y revuelta, por la adaptación negativa de la familia y el abandono de los hijos. Conclusión: la relación familiar de la persona mayor pasa por reajustes luego del comprometimiento de la capacidad funcional, lo que repercute significativamente en la dinámica de las relaciones. Desde esta comprensión, los profesionales de salud, sobre todo de enfermería, deben reconocer los retos a los que la familia afronta, orientarla y capacitarla para la atención a las demandas de cuidado presentadas por la persona mayor con comprometimiento de la capacidad funcional, y favorecer la realización del cuidado sin que esto desgaste las relaciones.

  19. CIUDADES INTELIGENTES COMO ESPACIOS DE INTEGRACIÓN PARA INDIVIDUOS CON CAPACIDADES DIVERSAS

    Directory of Open Access Journals (Sweden)

    Luisenia Fernández O.

    2014-07-01

    Full Text Available Hoy en día las Tecnologías de Información y Comunicación (TIC penetran en el entramado social y sobre él se configura la sociedad. Esta investigación describe el uso de las TIC en ciudades que distan desemejarse de la urbe tradicional gracias al empleo racional de las tecnologías que hacen los entornos más inteligentes, logrando cerrarlas brechas existentes entre sus usuario; generando el confort de aquellos cuyas capacidades son diversas en la diversidad o con capacidades disminuidas. Es decir, estas ciudades ponen a disposición de sus pobladores todos sus recursos tecnológicos disponibles y sus aportes al servicio de sus habitantes. La metodología utilizada para esta investigación fue de tipo exploratorio- descriptivo en la cual se intenta mostrar el uso de las tecnologías (TIC y la transformación del entorno, así como sus bondades en pro de la incorporación de los ciudadanos con capacidades diversas como ciudadanos de primera, a través de la construcción de espacios que aprovechan las aportaciones de las TIC para hacer del medio ambiente un espacio inteligente para la inclusión de los vulnerables cuyo fin último no es otro que el bienestar común. Se concluye que las denominadas ciudades inteligentes son hoy en día urbes que combinan la interconectividad de redes para la confortabilidad del ciudadano con capacidades diversas; éstas procuran el equilibrio, el desarrollo, la inclusión y el bienestar de los todos individuos con capacidades disímiles en la diversidad.

  20. Dopplervelocimetria das artérias uterinas na predição de complicações em gestações de baixo risco Uterine artery doppler velocimetry for the prediction of complications in low-risk pregnancies

    Directory of Open Access Journals (Sweden)

    Fabrício da Silva Costa

    2005-06-01

    Full Text Available OBJETIVO: determinar a validade da dopplervelocimetria das artérias uterinas na predição de complicações da gestação em população de nulíparas de baixo risco. MÉTODOS: foi conduzido estudo prospectivo que incluiu 45 pacientes primigestas, sem história de doenças crônicas. A dopplervelocimetria das artérias uterinas foi realizada entre 24 e 26 semanas, com determinação do índice de resistência (IR, índice de pulsatilidade (IP, relação S/D e a presença ou ausência de incisura na onda de velocidade de fluxo. Na análise estatística foi utilizado o teste de Mann-Whitney para amostras não paramétricas e o teste exato de Fisher foi utilizado na avaliação dos parâmentros qualitativos. RESULTADOS: complicações da gravidez foram observadas em 12 pacientes, com quatro casos de pré-eclâmpsia, um caso de recém-nascido pequeno para a idade gestacional (PIG, um caso de PIG e parto pré-termo (PPT, três casos de PPT, um caso de centralização fetal e dois casos de mecônio espesso no líquido amniótico no momento da resolução da gestação. Notamos que o IR (mediana 0,56 x 0,68, IP (mediana 0,98 x 1,29 e a relação S/D (mediana 2,2 x 2,9 estavam mais elevados no exame realizado entre a 24 e a 26ª semana nas pacientes que apresentaram qualquer complicação da gestação e não mostrou diferença nos casos de pré-eclâmpsia ou PIG. A presença de incisura bilateral apresentou sensibilidade de 100 e 90%, especificidade de 60,6 e 62,5%, valor preditivo positivo (VPP de 29,4 e 42,9%, valor preditivo negativo (VPN de 100 e 95,2% para a detecção de pré-eclâmpsia ou PIG e qualquer complicação da gestação, respectivamente. A dopplervelocimetria alterada apresentou sensibilidade de 83,3 e 83,3%, especificidade de 69,7 e 69,7%, VPP de 33,3 e 50,0%, VPN de 95,8 e 92,0% para a detecção de pré-eclâmpsia ou PIG e qualquer complicação da gestação, respectivamente. CONCLUSÃO: índices de alta impedância e a presen

  1. In vitro contractile effects of agents used in the clinical management of postpartum haemorrhage.

    Science.gov (United States)

    Morrison, John J; Crosby, David A; Crankshaw, Denis J

    2016-10-15

    Uterine atony is a major cause of postpartum haemorrhage and maternal mortality. However, the comparative pharmacology of agents used to treat this condition is poorly understood. This study evaluates, using human pregnant myometrium in vitro, a range of contractile parameters for agents used in the clinical treatment of atonic postpartum haemorrhage. The effects of oxytocin, carbetocin, ergometrine, carboprost, syntometrine and misoprostol were investigated in 146 myometrial strips from 19 donors. The potency and maximal response values were obtained, and compared, using both maximal amplitude and mean contractile force as indices of contraction. Single, EC50 concentrations of the agents were administered and both force and contraction peak parameters were compared during a 15-min exposure. Differences were considered significant when Poxytocin and carbetocin being the most potent. The most important difference between the agents was in their ability to increase the mean contractile force, with oxytocin superior to all agents except syntometrine. In single dose experiments, mean contractile force was the parameter that separated the agents. In this respect, oxytocin was not statistically different from carboprost or syntometrine, but was superior to all other agents. These findings support a clear role for oxytocin as the first line agent for treatment of postpartum haemorrhage and raise doubts about the potential clinical usefulness of misoprostol. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Smoothelin-B deficiency results in reduced arterial contractility, hypertension, and cardiac hypertrophy in mice

    NARCIS (Netherlands)

    Rensen, Sander S.; Niessen, Petra M.; van Deursen, Jan M.; Janssen, Ben J.; Heijman, Edwin; Hermeling, Evelien; Meens, Merlijn; Lie, Natascha; Gijbels, Marion J.; Strijkers, Gustav J.; Doevendans, Pieter A.; Hofker, Marten H.; de Mey, Jo G. R.; van Eys, Guillaume J.

    2008-01-01

    Smoothelins are actin-binding proteins that are abundantly expressed in healthy visceral (smoothelin-A) and vascular (smoothelin-B) smooth muscle. Their expression is strongly associated with the contractile phenotype of smooth muscle cells. Analysis of mice lacking both smoothelins (Smtn-A/B(-/-)

  3. Acute hypoxia limits endurance but does not affect muscle contractile properties.

    NARCIS (Netherlands)

    Degens, H.; Sanchez Horneros, J.M.; Hopman, M.T.E.

    2006-01-01

    Acute hypoxia causes skeletal muscle dysfunction in vitro, but little is known about its effect on muscle function in vivo. In 10 healthy male subjects, isometric contractile properties and fatigue resistance of the quadriceps muscle were determined during normoxia and hypoxia using electrically

  4. Effect of a Carbohydrate-Rich Diet on Rat Detrusor Smooth Muscle Contractility: An Experimental Study

    Directory of Open Access Journals (Sweden)

    Mustafa Suat Bolat

    2017-01-01

    Full Text Available Objectives. We aimed to investigate the effect of a carbohydrate-rich diet on detrusor contractility in rats. Materials and Methods. Sprague-Dawley rats were randomized into two groups. The control group received regular food and water. The study group received carbohydrate-rich diet for six weeks. The rats’ detrusor muscle was isolated for pharmacological and histopathological examinations. Results. In the control and study groups, mean body weights were 431.5 ± 27.6 g and 528.0 ± 36.2 g, respectively (p < 0.001. Electrical stimulation of the detrusor strips of the control group resulted in gradual contraction. A decreased contractile response was shown in the study group. Acetylcholine in 10-7-10-3 molar concentration produced a decreased contractile response in the study group, compared to the control group (p < 0.01. The study group showed marked subepithelial and intermuscular fibrosis in the bladder. Conclusion. Carbohydrate-rich diet causes marked subepithelial and extracellular fibrosis and changes in contractility in the detrusor within a six-week period. Changes have higher costs in therapeutic choices and correction of these changes remains difficult. Putting an end to carbohydrate-rich diet would seem to be more cost-effective than dealing with the effects of consuming it in high proportions which should be the national policy worldwide.

  5. Prolonged ischemic heart disease and coronary artery bypass - relation to contractile reserve

    DEFF Research Database (Denmark)

    Kofoed, Klaus F; Bangsgaard, Regitze; Carstensen, Steen

    2002-01-01

    OBJECTIVE: A major effect of coronary artery bypass grafting (CABG) in patients with ischemic heart disease and impaired left ventricular (LV) contractile function is believed to be an improvement in LV function due to recovery of dysfunctional, but viable myocardium. However, recent studies have...

  6. Effect of short-term outlet obstruction on rat bladder nerve density and contractility

    NARCIS (Netherlands)

    Barendrecht, M. M.; Chichester, P.; Michel, M. C.; Levin, R. M.

    2007-01-01

    1 The present study was designed to investigate the relationship between innervation density and contractile responses to field stimulation and exogenous agonists at early time points after induction of bladder outlet obstruction (BOO) in rats. 2 When compared with sham-operated animals, 1, 3 and 7

  7. Contractile responses to ergotamine and dihydroergotamine in the perfused middle cerebral artery of rat

    DEFF Research Database (Denmark)

    Tfelt-Hansen, Peer; Nilsson, Elisabeth; Edvinsson, Lars

    2007-01-01

    mmHg and luminally perfused. All vessels used attained spontaneous contractile tone (34.9+/-1.8% of resting tone) and responded to luminal adenosine triphosphate (ATP) with dilatation (24.1+/-4.0%), which showed functioning endothelium. Luminally added ergotamine or DHE induced maximal contractions...

  8. Gallbladder contractility and mucus secretion after cholesterol feeding in the prairie dog

    NARCIS (Netherlands)

    Li, Y. F.; Moody, F. G.; Weisbrodt, N. W.; Zalewsky, C. A.; Coelho, J. C.; Senninger, N.; Gouma, D.

    1986-01-01

    The purpose of our study was to evaluate changes in gallbladder contractility and mucus secretion in vitro during the early stages of gallstone formation in prairie dogs. Thirty-two animals were divided into five groups. Control animals were fed a trace cholesterol diet. Experimental animals were

  9. Hydrogen ion changes and contractile behavior in the perfused rat heart

    NARCIS (Netherlands)

    Cingolani, H.E.; Maas, A.H.J.; Zimmerman, A.N.E.; Meijler, F.L.

    1975-01-01

    The effect of acid-base alterations was analyzed using isolated rat hearts perfused at constant coronary perfusion pressure, and stimulated to contract at constant rate. The amount of shortening in the major axis and its derivative were measured to assess myocardial contractility. Both the

  10. The importance of myocardial contractile reserve in predicting response to cardiac resynchronization therapy

    NARCIS (Netherlands)

    Kloosterman, Mariëlle; Damman, Kevin; Van Veldhuisen, Dirk J; Rienstra, Michiel; Maass, Alexander H

    AimTo perform a meta-analysis and systematic review of published data to assess the relationship between contractile reserve and response to cardiac resynchronization therapy (CRT) in patients with heart failure. Methods and resultsWe searched MEDLINE/PubMed and Cochrane for all papers published up

  11. ATP-induced changes in rat skeletal muscle contractility.

    Science.gov (United States)

    Gabdrakhmanov, A I; Khayrullin, A E; Grishin, C H; Ziganshin, A U

    2015-01-01

    considered as typical effects of ATP and other purines on skeletal muscles and could not be extrapolated to all warm-blooded animals. Furthermore the role of ATP and its derivatives in the accumulation of vertebrate muscular effort has not been investigated.It is known that in physiological conditions vertebrates may mobilize only up to a third of the maximum muscle force. Why the two-thirds of muscular strength are not used normally but may be used at stress, remains unknown.It is known that the body's adaptive response to stress is a change in the activity of the endocrine system. The leading role in this is given to catechol amines and glucocorticoids, mobilized in significant quantities in blood under stress.We have found previously that incubation of frog sartorius muscle with hydrocortisone resulted in a decrease of contraction amplitude. However, when hydrocortisone was used in combination with ATP, its inhibitory effect on contractile responses disappeared. It is interesting that hydrocortisone had no effect on the inhibitory effect of adenosine. In the following experiments, assessing the effect of hydrocortisone on rat soleus muscle, it was established that hydrocortisone and purines had similar inhibitory effect. When ATP and hydrocortisone were given together the same oppression occurred. To study the effects of ATP and adenosine on contraction parameters of rat skeletal muscle and assess the impact of the catechol amines on these processes. Contractions of rat soleus muscles were recorded isometrically by mechanical sensor Linton FSG-01 (UK) according to standard procedures. The average of muscle parameters received within 30 seconds (30 responses) was treated as one result. Amplitude and time characteristics of the curve reductions were estimated. During all experiments standard Krebs solution flowed through the bath continuously to which agents were added at necessary concentrations. All experimental animals were maintained and prepared for dissection under

  12. Gene transfer of heterologous G protein-coupled receptors to cardiomyocytes: differential effects on contractility.

    Science.gov (United States)

    Laugwitz, K L; Weig, H J; Moretti, A; Hoffmann, E; Ueblacker, P; Pragst, I; Rosport, K; Schömig, A; Ungerer, M

    2001-04-13

    In heart failure, reduced cardiac contractility is accompanied by blunted cAMP responses to beta-adrenergic stimulation. Parathyroid hormone (PTH)-related peptide and arginine vasopressin are released from the myocardium in response to increased wall stress but do not stimulate contractility or adenylyl cyclase at physiological concentrations. To bypass the defective beta-adrenergic signaling cascade, recombinant P1 PTH/PTH-related peptide receptors (rPTH1-Rs) and V(2) vasopressin receptors (rV(2)-Rs), which are normally not expressed in the myocardium and which are both strongly coupled to adenylyl cyclase, and recombinant beta(2)-adrenergic receptors (rbeta(2)-ARs) were overexpressed in cardiomyocytes by viral gene transfer. The capacity of endogenous hormones to increase contractility via the heterologous, recombinant receptors was compared. Whereas V(2)-Rs are uniquely coupled to Gs, PTH1-Rs and beta(2)-ARs are also coupled to other G proteins. Gene transfer of rPTH1-Rs or rbeta(2)-ARs to adult cardiomyocytes resulted in maximally increased basal contractility, which could not be further stimulated by adding receptor agonists. Agonists at rPTH1-Rs induced increased cAMP formation and phospholipase C activity. In contrast, healthy or failing rV(2)-R-expressing cardiomyocytes showed unaltered basal contractility. Their contractility and cAMP formation increased only at agonist exposure, which did not activate phospholipase C. In summary, we found that gene transfer of PTH1-Rs to cardiomyocytes results in constitutive activity of the transgene, as does that of beta(2)-ARS: In the absence of receptor agonists, rPTH1-Rs and rbeta(2)-ARs increase basal contractility, coupling to 2 G proteins simultaneously. In contrast, rV(2)-Rs are uniquely coupled to Gs and are not constitutively active, retaining their property to be activated exclusively on agonist stimulation. Therefore, gene transfer of V(2)-Rs might be more suited to test the effects of c

  13. Indicadores antropométricos de estado nutricional como preditores de capacidade em idosos

    Directory of Open Access Journals (Sweden)

    Kleyton Trindade Santos

    2014-06-01

    Full Text Available INTRODUÇÃO: Trata-se de estudo seccional que analisou dados de pesquisa epidemiológica de base populacional e domiciliar conduzida em um município do nordeste do Brasil. OBJETIVO: Identificar os indicadores antropométricos de estado nutricional que apresentam melhor capacidade preditiva de capacidade funcional em idosos. MÉTODOS: A população foi constituída por 316 idosos que foram avaliados por meio de questionário contendo informações sociodemográficas, atividade física e condições de saúde, seguido de avaliação antropométrica. A capacidade funcional foi avaliada por meio das escalas de Katz e de Lawton e Brody para atividades básicas e instrumentais da vida diária, respectivamente. Foram utilizados como indicadores de estado nutricional, o índice de massa corporal, a área muscular do braço e o perímetro da panturrilha. Estimou-se modelos simples e múltiplos de regressão logística multinomial, tendo a capacidade funcional como variável dependente e os indicadores antropométricos como variáveis de interesse. RESULTADOS: Participaram do estudo 173 mulheres (54,7% e 143 homens (45,3%. Os resultados da regressão múltipla mostraram que o perímetro da panturrilha foi o único preditor de capacidade funcional em mulheres (≤ P25: OR = 5,77, p = 0,028, para dependência nas atividades instrumentais, enquanto que nos homens o índice de massa corporal foi o único indicador associado (baixo peso: OR = 11,36, p = 0,006; sobrepeso: OR = 22,06, p = 0,002; para dependência nas atividades básicas e instrumentais. CONCLUSÃO: Os resultados permitem concluir que os indicadores antropométricos preditores de capacidade funcional em idosos variam de acordo com o sexo, com o perímetro da panturrilha sendo mais adequada às mulheres e o índice de massa corporal aos homens.

  14. A CAPACIDADE INOVATIVA E O DESEMPENHO ECONÔMICO-FINANCEIRO DE EMPRESAS INOVADORAS BRASILEIRAS

    Directory of Open Access Journals (Sweden)

    Kléber Formiga Miranda

    Full Text Available RESUMOCom base nos pressupostos teóricos da Visão Baseada em Recursos (VBR, considerando a utilização de recursos disponíveis internamente nas organizações para manutenção de sua vantagem competitiva por meio da diferenciação, a pesquisa analisa a relação entre a capacidade inovativa e o desempenho econômico-financeiro de empresas brasileiras. A amostra foi extraída a partir das empresas listadas na BM&FBovespa consideradas inovadoras, segundo o IBI. As variáveis de capacidade inovativa coletadas a partir das PINTECs 2005 e 2008 e de desempenho através do Economática(r foram tratadas por meio de análises de correlação e de regressão. Os resultados indicam que os desempenhos econômico (ROA e operacional (EBITDA/Ativo Total não são significativamente influenciados pela capacidade inovativa. No entanto, quando se separa a capacidade inovativa por seus componentes (inovação de produto, processo, organizacional e marketing, observa-se uma influência positiva de inovação de produto sobre ambos os desempenhos. Por sua vez, o desempenho de valor (MVA é influenciado positiva e significativamente pela capacidade inovativa. Esses resultados sugerem melhores resultados contábeis quando as empresas inovam no produto e maior geração de valor pelo mercado ao possuir um portfólio diversificado de inovação, ou seja, maior capacidade inovativa. Não se pode, entretanto, negligenciar as inovações em processo, organizacional emarketing. A pouca relação dessas inovações, perceptíveis no âmbito interno da empresa, com o desempenho pode residir nas diferentes estratégias inovativas adotadas em prol do objetivo principal de cada empresa.

  15. A massa gorda de risco afeta a capacidade aeróbia de jovens adolescentes

    Directory of Open Access Journals (Sweden)

    Luís Massuça

    2013-12-01

    Full Text Available OBJETIVO: Estudar o comportamento do sexo e os efeitos da idade e da massa gorda sobre a capacidade aeróbia de jovens adolescentes. MÉTODOS: Os 621 estudantes do ensino secundário participantes no estudo (14 aos 17 anos; feminino: n = 329, idade, 15,84 ± 0,92 anos; masculino: n = 292, idade, 15,82 ± 0,87 anos foram avaliados em duas categorias: morfologia (altura, peso e % massa gorda - %MG e aptidão física (capacidade aeróbia. As medições antropométricas foram realizadas de acordo com o protocolo descrito por Marfell-Jones e a %MG foi calculada por bioimpedância. A avaliação da capacidade aeróbia foi realizada com o teste aeróbio de corrida - PACER, e VO2máx relativo foi calculado utilizando a equação de Léger. Os resultados das avaliações foram classificados de acordo com os valores normativos das tabelas de referência da bateria de testes FITNESSGRAM® As técnicas estatísticas utilizadas foram: 1 cálculo de frequências; 2 teste t de Student para amostras independentes; e 3 ANOVA two-way seguida do teste post-hoc HSD de Bonferroni. RESULTADOS: 1 existem diferenças significativas entre sexos no que se refere à %MG e ao VO2máx; 2 durante a adolescência, o VO2máx estabiliza nos rapazes e sofre um declínio nas moças; 3 independentemente do sexo, a classe de %MG e a idade cronológica têm um efeito significativo sobre a capacidade aeróbia; e 4 em jovens adolescentes, com %MG de risco, a redução da %MG para níveis saudáveis parece resultar na melhoria da capacidade aeróbia. CONCLUSÃO: O impacto da %MG na capacidade aeróbia, reforça a importância da educação física escolar na promoção da saúde cardiovascular.

  16. PKA catalytic subunit compartmentation regulates contractile and hypertrophic responses to β-adrenergic signaling

    Science.gov (United States)

    Yang, Jason H.; Polanowska-Grabowska, Renata K.; Smith, Jeffrey S.; Shields, Charles W.; Saucerman, Jeffrey J.

    2014-01-01

    β-adrenergic signaling is spatiotemporally heterogeneous in the cardiac myocyte, conferring exquisite control to sympathetic stimulation. Such heterogeneity drives the formation of protein kinase A (PKA) signaling microdomains, which regulate Ca2+ handling and contractility. Here, we test the hypothesis that the nucleus independently comprises a PKA signaling microdomain regulating myocyte hypertrophy. Spatially-targeted FRET reporters for PKA activity identified slower PKA activation and lower isoproterenol sensitivity in the nucleus (t50 = 10.60±0.68 min; EC50 = 89.00 nmol/L) than in the cytosol (t50 = 3.71±0.25 min; EC50 = 1.22 nmol/L). These differences were not explained by cAMP or AKAP-based compartmentation. A computational model of cytosolic and nuclear PKA activity was developed and predicted that differences in nuclear PKA dynamics and magnitude are regulated by slow PKA catalytic subunit diffusion, while differences in isoproterenol sensitivity are regulated by nuclear expression of protein kinase inhibitor (PKI). These were validated by FRET and immunofluorescence. The model also predicted differential phosphorylation of PKA substrates regulating cell contractility and hypertrophy. Ca2+ and cell hypertrophy measurements validated these predictions and identified higher isoproterenol sensitivity for contractile enhancements (EC50 = 1.84 nmol/L) over cell hypertrophy (EC50 = 85.88 nmol/L). Over-expression of spatially targeted PKA catalytic subunit to the cytosol or nucleus enhanced contractile and hypertrophic responses, respectively. We conclude that restricted PKA catalytic subunit diffusion is an important PKA compartmentation mechanism and the nucleus comprises a novel PKA signaling microdomain, insulating hypertrophic from contractile β-adrenergic signaling responses. PMID:24225179

  17. Predicting changes in cardiac myocyte contractility during early drug discovery with in vitro assays

    Energy Technology Data Exchange (ETDEWEB)

    Morton, M.J., E-mail: michael.morton@astrazeneca.com [Discovery Sciences, AstraZeneca, Macclesfield, Cheshire SK10 4TG (United Kingdom); Armstrong, D.; Abi Gerges, N. [Drug Safety and Metabolism, AstraZeneca, Macclesfield, Cheshire SK10 4TG (United Kingdom); Bridgland-Taylor, M. [Discovery Sciences, AstraZeneca, Macclesfield, Cheshire SK10 4TG (United Kingdom); Pollard, C.E.; Bowes, J.; Valentin, J.-P. [Drug Safety and Metabolism, AstraZeneca, Macclesfield, Cheshire SK10 4TG (United Kingdom)

    2014-09-01

    Cardiovascular-related adverse drug effects are a major concern for the pharmaceutical industry. Activity of an investigational drug at the L-type calcium channel could manifest in a number of ways, including changes in cardiac contractility. The aim of this study was to define which of the two assay technologies – radioligand-binding or automated electrophysiology – was most predictive of contractility effects in an in vitro myocyte contractility assay. The activity of reference and proprietary compounds at the L-type calcium channel was measured by radioligand-binding assays, conventional patch-clamp, automated electrophysiology, and by measurement of contractility in canine isolated cardiac myocytes. Activity in the radioligand-binding assay at the L-type Ca channel phenylalkylamine binding site was most predictive of an inotropic effect in the canine cardiac myocyte assay. The sensitivity was 73%, specificity 83% and predictivity 78%. The radioligand-binding assay may be run at a single test concentration and potency estimated. The least predictive assay was automated electrophysiology which showed a significant bias when compared with other assay formats. Given the importance of the L-type calcium channel, not just in cardiac function, but also in other organ systems, a screening strategy emerges whereby single concentration ligand-binding can be performed early in the discovery process with sufficient predictivity, throughput and turnaround time to influence chemical design and address a significant safety-related liability, at relatively low cost. - Highlights: • The L-type calcium channel is a significant safety liability during drug discovery. • Radioligand-binding to the L-type calcium channel can be measured in vitro. • The assay can be run at a single test concentration as part of a screening cascade. • This measurement is highly predictive of changes in cardiac myocyte contractility.

  18. Thrombopoietin modulates cardiac contractility in vitro and contributes to myocardial depressing activity of septic shock serum.

    Science.gov (United States)

    Lupia, Enrico; Spatola, Tiziana; Cuccurullo, Alessandra; Bosco, Ornella; Mariano, Filippo; Pucci, Angela; Ramella, Roberta; Alloatti, Giuseppe; Montrucchio, Giuseppe

    2010-09-01

    Thrombopoietin (TPO) is a humoral growth factor that has been shown to increase platelet activation in response to several agonists. Patients with sepsis have increased circulating TPO levels, which may enhance platelet activation, potentially participating to the pathogenesis of multi-organ failure. Aim of this study was to investigate whether TPO affects myocardial contractility and participates to depress cardiac function during sepsis. We showed the expression of the TPO receptor c-Mpl on myocardial cells and tissue by RT-PCR, immunofluorescence and western blotting. We then evaluated the effect of TPO on the contractile function of rat papillary muscle and isolated heart. TPO did not change myocardial contractility in basal conditions, but, when followed by epinephrine (EPI) stimulation, it blunted the enhancement of contractile force induced by EPI both in papillary muscle and isolated heart. An inhibitor of TPO prevented TPO effect on cardiac inotropy. Treatment of papillary muscle with pharmacological inhibitors of phosphatidylinositol 3-kinase, NO synthase, and guanilyl cyclase abolished TPO effect, indicating NO as the final mediator. We finally studied the role of TPO in the negative inotropic effect exerted by human septic shock (HSS) serum and TPO cooperation with TNF-alpha and IL-1beta. Pre-treatment with the TPO inhibitor prevented the decrease in contractile force induced by HSS serum. Moreover, TPO significantly amplified the negative inotropic effect induced by TNF-alpha and IL-1beta in papillary muscle. In conclusion, TPO negatively modulates cardiac inotropy in vitro and contributes to the myocardial depressing activity of septic shock serum.

  19. Retosiban Prevents Stretch-Induced Human Myometrial Contractility and Delays Labor in Cynomolgus Monkeys.

    Science.gov (United States)

    Aye, Irving L M H; Moraitis, Alexandros A; Stanislaus, Dinesh; Charnock-Jones, D Stephen; Smith, Gordon C S

    2018-03-01

    Stretch of the myometrium promotes its contractility and is believed to contribute to the control of parturition at term and to the increased risk of preterm birth in multiple pregnancies. To determine the effects of the putative oxytocin receptor (OTR) inverse agonist retosiban on (1) the contractility of human myometrial explants and (2) labor in nonhuman primates. Human myometrial biopsies were obtained at planned term cesarean, and explants were exposed to stretch in the presence and absence of a range of drugs, including retosiban. The in vivo effects of retosiban were determined in cynomolgus monkeys. Prolonged mechanical stretch promoted myometrial extracellular signal-regulated kinase (ERK)1/2 phosphorylation. Moreover, stretch-induced stimulation of myometrial contractility was prevented by ERK1/2 inhibitors. Retosiban (10 nM) prevented stretch-induced stimulation of myometrial contractility and phosphorylation of ERK1/2. Moreover, the inhibitory effect of retosiban on stretch-induced ERK1/2 phosphorylation was prevented by coincubation with a 100-fold excess of a peptide OTR antagonist, atosiban. Compared with vehicle-treated cynomolgus monkeys, treatment with oral retosiban (100 to 150 days of gestational age) reduced the risk of spontaneous delivery (hazard ratio = 0.07, 95% confidence interval 0.01 to 0.60, P = 0.015). The OTR acts as a uterine mechanosensor, whereby stretch increases myometrial contractility through agonist-free activation of the OTR. Retosiban prevents this through inverse agonism of the OTR and, in vivo, reduced the likelihood of spontaneous labor in nonhuman primates. We hypothesize that retosiban may be an effective preventative treatment of preterm birth in high-risk multiple pregnancies, an area of unmet clinical need.

  20. Dynamic MR cholangiography after fatty meal loading. Cystic contractility and dynamic evaluation of biliary stasis

    International Nuclear Information System (INIS)

    Omata, Takayuki; Saito, Kazuhiro; Kotake, Fumio; Mizokami, Yuji; Matsuoka, Takeshi; Abe, Kimihiko

    2002-01-01

    Dynamic MR cholangiography was conducted on patients with cholelithiasis or choledocholithiasis who had consumed a fatty test meal (Molyork) and the cystic contractility and dynamics of biliary stasis was evaluated. The subjects were 25 with intracystic cholelithiasis, 10 with choledocholithiasis and 10 normal controls. For an imaging sequence, the rapid acquisition with relaxation enhancement (RARE) method was employed and imaging was conducted for 40 min (every 30 s following Molyork administration) without breath-holding. The gallbladder contraction ratio was computed and the contractile ratio for the common bile duct was calculated. To determine the bile flow to the duodenum, the high-intensity signal, indicating the flow from the lower common bile duct, and perfusion of the duodenum were observed in dynamic mode on the monitor with the naked eye and interpreted as positive bile flow. The frequency of this flow was visually monitored. The gallbladder contractile ratio was significantly reduced in patients with cholelithiasis or choledocholithiasis compared with the controls. In a comparison with the normal controls, no sequential changes were noted in the mean contractile ratio of the common bile duct of the patients with cholelithiasis or choledocholithiasis. The mean frequency of bile flow observed for each 40 min period was 13±2.4, 6±2.2, and 4±1.3 times for the controls, those with intracystic cholelithiasis, and those with choledocholithiasis, respectively. Compared with the controls, the latter two patient groups showed evident reductions in the frequency of bile flow to the duodenum (p<0.001). Dynamic MRC combined with Molyork loading makes it possible to compute cystic contractile ratios and perform a dynamic examination of bile flow under non-invasive, near-physiological conditions. (author)

  1. Changes in contractile activation characteristics of rat fast and slow skeletal muscle fibres during regeneration.

    Science.gov (United States)

    Gregorevic, Paul; Plant, David R; Stupka, Nicole; Lynch, Gordon S

    2004-07-15

    Damaged skeletal muscle fibres are replaced with new contractile units via muscle regeneration. Regenerating muscle fibres synthesize functionally distinct isoforms of contractile and regulatory proteins but little is known of their functional properties during the regeneration process. An advantage of utilizing single muscle fibre preparations is that assessment of their function is based on the overall characteristics of the contractile apparatus and regulatory system and as such, these preparations are sensitive in revealing not only coarse, but also subtle functional differences between muscle fibres. We examined the Ca(2+)- and Sr(2+)-activated contractile characteristics of permeabilized fibres from rat fast-twitch (extensor digitorum longus) and slow-twitch (soleus) muscles at 7, 14 and 21 days following myotoxic injury, to test the hypothesis that fibres from regenerating fast and slow muscles have different functional characteristics to fibres from uninjured muscles. Regenerating muscle fibres had approximately 10% of the maximal force producing capacity (P(o)) of control (uninjured) fibres, and an altered sensitivity to Ca(2+) and Sr(2+) at 7 days post-injury. Increased force production and a shift in Ca(2+) sensitivity consistent with fibre maturation were observed during regeneration such that P(o) was restored to 36-45% of that in control fibres by 21 days, and sensitivity to Ca(2+) and Sr(2+) was similar to that of control (uninjured) fibres. The findings support the hypothesis that regenerating muscle fibres have different contractile activation characteristics compared with mature fibres, and that they adopt properties of mature fast- or slow-twitch muscle fibres in a progressive manner as the regeneration process is completed.

  2. Predicting changes in cardiac myocyte contractility during early drug discovery with in vitro assays

    International Nuclear Information System (INIS)

    Morton, M.J.; Armstrong, D.; Abi Gerges, N.; Bridgland-Taylor, M.; Pollard, C.E.; Bowes, J.; Valentin, J.-P.

    2014-01-01

    Cardiovascular-related adverse drug effects are a major concern for the pharmaceutical industry. Activity of an investigational drug at the L-type calcium channel could manifest in a number of ways, including changes in cardiac contractility. The aim of this study was to define which of the two assay technologies – radioligand-binding or automated electrophysiology – was most predictive of contractility effects in an in vitro myocyte contractility assay. The activity of reference and proprietary compounds at the L-type calcium channel was measured by radioligand-binding assays, conventional patch-clamp, automated electrophysiology, and by measurement of contractility in canine isolated cardiac myocytes. Activity in the radioligand-binding assay at the L-type Ca channel phenylalkylamine binding site was most predictive of an inotropic effect in the canine cardiac myocyte assay. The sensitivity was 73%, specificity 83% and predictivity 78%. The radioligand-binding assay may be run at a single test concentration and potency estimated. The least predictive assay was automated electrophysiology which showed a significant bias when compared with other assay formats. Given the importance of the L-type calcium channel, not just in cardiac function, but also in other organ systems, a screening strategy emerges whereby single concentration ligand-binding can be performed early in the discovery process with sufficient predictivity, throughput and turnaround time to influence chemical design and address a significant safety-related liability, at relatively low cost. - Highlights: • The L-type calcium channel is a significant safety liability during drug discovery. • Radioligand-binding to the L-type calcium channel can be measured in vitro. • The assay can be run at a single test concentration as part of a screening cascade. • This measurement is highly predictive of changes in cardiac myocyte contractility

  3. Associação entre a Incisura Diastólica das Artérias Uterinas e a Histologia do Leito Placentário em Grávidas com Pré-eclâmpsia Association between Diastolic Notch of Uterine Artery and the Histology of the Placental Bed in Pregnant Women with Preeclampsia

    Directory of Open Access Journals (Sweden)

    Regina Amélia Lopes Pessoa de Aguiar

    2001-08-01

    Full Text Available Objetivo: avaliar a associação entre a presença da incisura diastólica nas artérias uterinas maternas e as alterações histopatológicas dos vasos útero-placentários. Métodos: estudo transversal incluindo 144 pacientes com gestação única interrompida por via abdominal entre a 27ª e a 41ª semana. Destas, 84 gestações estavam associadas à pré-eclâmpsia e 60 não apresentaram intercorrências clínicas. Neste grupo realizou-se dopplerfluxometria de ambas as artérias uterinas e biópsia do leito placentário. Resultados: das 144 pacientes, 88 (61% tiveram o fragmento da biópsia considerado representativo do leito placentário. A incisura diastólica estava presente em 40 (70% dos casos de alterações fisiológicas inadequadas e ausente em 28 (90% dos casos de alterações fisiológicas presentes (p=0,05. A dopplerfluxometria apresentou sensibilidade de 70%, especificidade de 90% e valores preditivos positivo e negativo de 44 e 97%, respectivamente. A associação entre a presença de incisura diastólica bilateral das artérias uterinas e arteriopatia decidual também foi significativa (dos 25 casos de arteriopatia decidual a incisura estava presente em 24, p=0,05. A sensibilidade da dopplerfluxometria foi de 96%, especificidade de 70% e valores preditivos positivo e negativo de 26 e 99%, respectivamente, ao passo que para a arteriolosclerose a dopplerfluxometria apresentou sensibilidade de 80%, especificidade de 55% e valores preditivos positivo e negativo de 17 e 96%, respectivamente. Conclusões: a incisura diastólica nas artérias uterinas maternas é indicador seguro de vasculopatia no leito placentário. A adequada invasão trofoblástica do leito placentário, revelada por histologia típica de alterações fisiológicas, resulta na ausência de incisura diastólica bilateral das artérias uterinas maternas.Purpose: to evaluate the association between the presence of diastolic notch in the maternal uterine arteries, and

  4. Um índice de capacidade para especificações unilaterais

    OpenAIRE

    Barriga,Gladys D. Cacsire; Ho,Linda Lee; Borges,Wagner Sousa

    2003-01-01

    Nos últimos anos, índices de capacidade de processos têm sido usados freqüentemente para determinar se um processo é capaz de produzir itens em conformidade com a tolerância especificada. No entanto, poucos estudos têm sido feitos acerca de índices de capacidade para situações em que há apenas um limite de especificação. Neste trabalho, um índice para situações em que há apenas um limite de especificação é apresentado. Ele é invariante com respeito à fração não-conforme do processo e "calibra...

  5. Orientación Emprendedora, Capacidad de Aprendizaje Organizativo y Desempeño Innovador

    Directory of Open Access Journals (Sweden)

    Anabel Fernández Mesa

    2012-07-01

    Full Text Available Este artículo examina la relación entre la orientación emprendedora y el desempeño innovador tomando como variable mediadora la capacidad de aprendizaje organizativo. Esta cuestión de investigación es importante porque nos permite comprender mejor por qué la orientación emprendedora no afecta siempre de forma positiva a la cuenta de resultados. Consideramos que el desempeño innovador es una medida muy próxima al resultado general. Utilizando un modelo de ecuaciones estructurales en una muestra de 182 empresas de la industria cerámica, los resultados muestran que la capacidad de aprendizaje organizativo juega un rol fundamental en determinar los efectos de la orientación emprendedora en el desempeño innovador.

  6. Governança e capacidades estatais: uma análise comparativa de programas federais

    Directory of Open Access Journals (Sweden)

    Roberto Rocha Coelho Pires

    Full Text Available Resumo O artigo se dedica ao exame dos arranjos institucionais que marcaram a implementação de políticas públicas pelo governo federal no Brasil na última década. Pretende-se compreender de que forma as características desses arranjos condicionaram as capacidades estatais disponíveis e afetaram o desempenho e os resultados até então observados de políticas públicas pré-selecionadas. A pesquisa se baseia em uma análise comparativa de oito casos de políticas públicas federais prioritárias no período recente (nomeadamente entre os anos de 2003 e 2013. Os casos foram selecionados em função da homogeneidade de seus contextos de implementação e da heterogeneidade de suas áreas temáticas (social, infraestrutura e desenvolvimento industrial. A partir do mapeamento dos arranjos institucionais e da avaliação de capacidades técnico-administrativas e político-relacionais de cada caso, desenvolveu-se uma comparação entre os casos baseada em técnicas de QCA (Qualitative Comparative Analysis, as quais permitiram identificar associações e mecanismos causais entre as características dos arranjos, tipos e níveis de capacidades estatais e o desempenho observado por fontes secundárias das políticas públicas em termos de entrega de resultados e inovação. A análise comparativa indicou uma expressiva variação na configuração dos arranjos institucionais que sustentam a implementação de políticas federais contemporâneas. O exame dessa variação apontou dois achados relevantes. De um lado, verificou-se que os arranjos institucionais indutores de altas capacidades técnico-administrativas, envolvendo combinação de organizações profissionalizadas com mecanismos efetivos de coordenação intra e intergovernamentais, tendem a promover um melhor desempenho relativo em termos de entrega de resultados. De outro lado, arranjos promotores de altas capacidades político-relacionais, envolvendo interações com agentes pol

  7. Análisis de la capacidad de aceleración en mujeres atletas de modalidades de velocidad

    OpenAIRE

    Carmona Dalmases, Gerard; González-Haro, Carlos

    2012-01-01

    Objetivos. Caracterizar la capacidad de aceleración con relación al rendimiento (tiempo en sprint de 30 m), la velocidad máxima y las manifestaciones de fuerza (capacidad de salto) y potencia (en ½ squat) musculares en 4 mujeres atletas de especialidades de velocidad de nivel nacional. Métodos. Se realizaron dos días de pruebas (pista y laboratorio). Se valoró la capacidad de aceleración (velocidades instantánea a 1, 2 y 3 s –vi1, vi2 i vi3–), aceleración inicial (ainicial), tiempo de sprint ...

  8. Las nominaciones de los profesores en la identificación de alumnos de alta capacidad intelectual

    OpenAIRE

    Tourón, J. (Javier); Repáraz, C. (Charo); Peralta, F. (Feli)

    2006-01-01

    La capacidad de los profesores para identificar, a través de sus nominaciones, a los alumnos de alta capacidad intelectual en la Clase regular, es uno de los aspectos más controvertidos en la literatura de investigación. Mientras unos trabajos señalan la adecuación y conveniencia de las mismas, otros estudios ponen de manifiesto su falta de consitencia. En este estudio analizamos las nominaciones de los profesores en un proceso de identificación de alumnos de alta capacidad intelectual ...

  9. À espera da seca que vem: capacidade adaptativa em comunidades rurais do semiárido

    Directory of Open Access Journals (Sweden)

    Ansu Mancal

    Full Text Available Este artigo avalia a disponibilidade de recursos necessários para criação de capacidade adaptativa em comunidades rurais do semiárido brasileiro. A pesquisa utiliza dados primários obtidos por meio de aplicação de questionários. Dada a grande extensão geográfica da região, adota-se como recorte uma amostra de comunidades rurais inseridas em áreas susceptíveis à desertificação no Estado do Ceará. A discussão é feita a partir de um sistema de indicadores definido por meio de consultas a especialistas (método Delphi e subdividido em quatro dimensões da capacidade adaptativa: capital social, capital econômico, capital humano e capital natural, pressupondo que a capacidade adaptativa é definida pela disponibilidade de um conjunto de recursos capazes de promover o bem-estar local. A análise da distribuição dos indicadores selecionados mostra que as comunidades possuem baixos níveis de recursos necessários para adaptação, sendo que os pontos mais críticos são destacados na dimensão de capital humano. No contexto observado acredita-se que as ações governamentais que poderiam melhorar a capacidade adaptativa das comunidades rurais do semiárido em relação às secas não encontram ambiente social propício para expressarem seu potencial, sendo o maior desafio a adoção de estratégias integradas de educação e capacitação da população que atuem de forma transversal em todas as políticas voltadas para o desenvolvimento local.

  10. A Mobilização de Capacidades Dinâmicas na Lojas Renner

    Directory of Open Access Journals (Sweden)

    Adalberto Escalona Gonçalves Garcia

    2014-03-01

    Full Text Available O artigo tem como objetivo analisar a trajetória de uma das empresas varejistas de maior destaque no mercado brasileiro, através de um estudo longitudinal que enfatiza a mobilização de seus recursos e capacidades ao longo de 90 anos de história. Explorando o conceito de capacidades dinâmicas, descrevem-se as ações estratégicas empreendidas em momentos de crescimento e de crise. Para tanto, foram realizadas entrevistas em profundidade com dez tomadores de decisão que vivenciaram diferentes momentos da história da empresa e que desempenharam distintos papéis nos últimos 50 anos. Além disso, dado o aspecto histórico da pesquisa, especial ênfase foi dada à obtenção e à análise de dados secundários. Boletins internos, comunicados ao mercado de capitais, relatórios anuais, demonstrações financeiras, artigos da mídia, entre outras fontes, totalizaram mais cerca de 600 páginas de material analisado. No que diz respeito às contribuições teóricas, a pesquisa identificou a existência de quatro mecanismos de mobilização das capacidades dinâmicas: a alavancagem, a criação, o acesso e a liberação de recursos e de capacidades. Com relação às implicações gerenciais, o estudo mostrou que habilidades dos gestores vinculadas seletivamente aos quatro mecanismos de mobilização se tornam essenciais na condução de uma empresa em seus momentos, tanto de estabilidade e crescimento, quanto de turbulência. DOI:10.5585/riae.v13i1.2029

  11. Uso público y capacidad de carga perceptual en espacios naturales protegidos

    Directory of Open Access Journals (Sweden)

    Felipe Leco Berrocal

    2013-01-01

    Full Text Available Este trabajo muestra algunos de los resultados de la investigación realizada en el Proyecto «Las áreas de uso público en la Reserva de la Biosfera de Monfragüe. Accesibilidad y capacidad de carga» (Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica 2004-2007. Orden MAM/321/207. Expte. 024/SGTB/2007/4.1. En líneas generales, se presenta un estudio de las principales áreas de uso público desde la perspectiva de la capacidad de carga, ya que dichas áreas polarizan por regla general los flujos de usuarios, las inversiones y son el eje principal sobre el que descansa la afluencia de usuarios al Parque, por ello es necesario evaluar no sólo la capacidad de carga sino también la intensidad de su uso.

  12. Proposta para estimar curva carga-recalque e capacidade de carga em estacas de madeira

    Directory of Open Access Journals (Sweden)

    Pedro Gutemberg de Alcântara Segundinho

    Full Text Available Este trabalho teve como objetivo propor um método para estimar a curva carga-recalque e a capacidade de carga de estacas de madeira a partir do ajuste de equações de regressão não lineares utilizando o método de Gauss Newton modificado. Para isso, foram utilizados dados experimentais obtidos para 12 estacas de madeira, curvas carga-recalque durante a cravação e capacidade de carga determinada no ensaio de carregamento dinâmico, utilizando modelo teórico. Nesta pesquisa, realizada de forma pioneira no Brasil, fez-se a análise do comportamento de estacas de madeira imersas no solo durante a cravação delas. As médias do erro percentual absoluto médio foram 4,0% e 29,3%, obtidas a partir das equações não lineares ajustadas via método de Gauss Newton modificado e proposto por Van Der Veen respectivamente. Concluiu-se que as equações ajustadas via método de Gauss Newton modificado conduziram a uma maior exatidão nas estimativas, apresentando boa concordância com os dados experimentais obtidos nos ensaios de carregamento dinâmico, indicando sua utilização para estimar a curva carga-recalque e a capacidade de carga em estacas de madeira.

  13. ¿Contribuyen las asignaturas de finanzas al desarrollo de la capacidad gerencial del administrador?

    Directory of Open Access Journals (Sweden)

    Luis M. Prada B.

    1996-12-01

    Full Text Available En este artículo el autor presenta los resultados de un trabajo de investigación sobre el aporte de las asignaturas de finanzas al desarrollo de capacidades gerenciales de innovación, liderazgo, comunicación e integridad ética, entre estudiantes de la carrera de Administración en la Universidad Nacional de Colombia. La investigación se realizó de dos maneras: una teórica, consistente en verificar que los programas de esas asignaturas mencionaran de manera explícita en los objetivos, contenidos, metodologías y formas de evaluación, la intención de propiciar el desarrollo de dichas capacidades. La otra, práctica, consistente en conocer la opinión de los estudiantes sobre el aporte real que hicieron esas asignaturas a su desarrollo personal y profesional, con respecto a las mencionadas capacidades. Según los estudiantes, los programas de las cuatro asignaturas obligatorias de finanzas no integran, ni en su enunciado, ni en su desarrollo, principios y estrategias educativas, elementos que promuevan el desarrollo de las mencionadas características gerenciales.

  14. [Gallbladder contractility in children with functional abdominal pain or irritable bowel syndrome].

    Science.gov (United States)

    Iwańczak, Franciszek; Siedlecka-Dawidko, Jolanta; Iwanczak, Barbara

    2013-07-01

    III Rome Criteria of functional gastrointestinal disorders in children, distinguished the disturbances with abdominal pain, to which irritable bowel syndrome, functional abdominal pains, functional dyspepsia and abdominal migraine were included. THE AIM OF THE STUDY was sonographic assessment of the gallbladder and its contractility in functional abdominal pain and irritable bowel syndrome in children. The study comprised 96 children aged 6 to 18 years, 59 girls and 37 boys. Depending on diagnosis, the children were divided into three groups. 38 children with functional abdominal pain constituted the first group, 26 children with irritable bowel syndrome were included to the second group, the third group consisted of 32 healthy children (control group). Diagnosis of functional abdominal pain and irritable bowel syndrome was made based on the III Rome Criteria. In irritable bowel syndrome both forms with diarrhea (13) and with constipation (13) were observed. Anatomy and contractility of the gallbladder were assessed by ultrasound examination. The presence of septum, wall thickness, thick bile, vesicle volume in fasting state and 30th and 60th minute after test meal were taken into consideration. Test meal comprised about 15% of caloric requirement of moderate metabolism. Children with bile stones and organic diseases were excluded from the study. Thickened vesicle wall and thick bile were present more frequently in children with irritable bowel syndrome and functional abdominal pain than in control group (p functional abdominal pain than in irritable bowel syndrome and control group (p = 0.003, p = 0.05). Vesicle contractility after test meal was greatest in children with functional abdominal pain. Evaluation of diminished (smaller than 30%) and enlarged (greater then 80%) gallbladder contractility at 30th and 60th minute after test meal demonstrated disturbances of contractility in children with irritable bowel syndrome and functional abdominal pain. In children

  15. El derecho a la salud: una visión a partir del enfoque de capacidades

    Directory of Open Access Journals (Sweden)

    Alba L. Vélez Arango

    2015-02-01

    Full Text Available Objetivos: 1 identificar en las tesis libertarias y en la tradición liberal igualitaria de John Rawls la aceptación y/o rechazo de la protección de la salud como requisito de justicia social. 2 Analizar en los idearios teóricos de Amartya Sen y Martha Nussbaum elementos a favor de la protección de la salud y su goce efectivo como parte de los derechos que deben reconocerse por la sociedad, como respuesta a cuestiones de justicia social. Metodología: investigación de carácter filosófico, analizó críticamente los fundamentos morales y políticos que sustentan el reconocimiento del derecho a la salud como un requisito de justicia social. Resultados: en el proyecto rawlsiano la estructura básica de la sociedad debe distribuir ciertos “bienes primarios”, cosas que se presume que todo ser racional desea para poder desarrollar los planes de vida. Amartya Sen y Martha Nussbaum proponen el enfoque de las capacidades humanas básicas; el primero lo justifica en torno a la libertad y la segunda como requisitos básicos para una vida digna. Nussbaum justifica una lista de diez capacidades, dentro de las cuales incluye la vida, la salud física y la integridad física; todas relacionadas directamente con la salud. Así la tutela en salud se torna en condición necesaria de justicia social. El enfoque de las capacidades introduce la idea de un umbral para cada capacidad, por debajo del cual se considera que los ciudadanos no pueden funcionar de un modo auténticamente humano. Conclusiones: la protección de la salud instrumentalizada a través del sistema de salud es condición necesaria para el desarrollo de la vida que cada individuo tiene razones para valorar. Su protección debe darse dentro de los umbrales mínimos de justicia y la meta social debería entenderse en el sentido de lograr que los ciudadanos se sitúen por encima de este conjunto de capacidades entre las que se encuentra la salud.

  16. UN ANÁLISIS DE LA CAPACIDAD ESPACIAL EN ESTUDIOS DE INGENIERÍA TÉCNICA

    Directory of Open Access Journals (Sweden)

    Iera Arrieta

    2015-01-01

    Full Text Available Desde el siglo pasado se ha recalcado la importancia que tiene la capacidad espacial en la inteligencia y en la enseñanza-aprendizaje de las matemáticas. En este trabajo se ha elegido el modelo de Carroll para analizar la capacidad espacial del alumnado de la Escuela Politécnica Universitaria de San Sebastián. Se han planteado tres objetivos: (a analizar la capacidad espacial de los estudiantes de primero en función de la especialidad y del sexo, y en relación con la nota obtenida en dibujo técnico; (b analizar, igualmente, la capacidad espacial de los estudiantes de tercero; y (c comparar ambos resultados

  17. Effect of changes in contractility on the index of myocardial performance in the dysfunctional left ventricle

    Directory of Open Access Journals (Sweden)

    Lavine Steven J

    2006-11-01

    Full Text Available Abstract Background The index of myocardial performance has prognostic power in patients with cardiomyopathy and following myocardial infarction. As the index of myocardial performance has been shown to be preload and afterload dependent, the effect of altering contractility on IMP and its components with left ventricular dysfunction has been incompletely delineated. Methods Chronic left ventricular dysfunction was induced in 10 canines using coronary microsphere embolization. Each dog was instrumented and imaged with 2D echo and Doppler. At the same atrially paced rate, contractility was increased with a dobutamine infusion and then following 4 weeks of oral digoxin. Results With chronic left ventricular dysfunction, a reduced left ventricular ejection fraction (42 ± 3%, p Conclusion Increased inotropy with digoxin and dobutamine reduced the index of myocardial performance in dogs with left ventricular dysfunction. Shortened isovolumic contraction time, increased diastolic filling period, and reduced left ventricular end diastolic pressure with digoxin may provide insight into its efficacy in heart failure.

  18. An Estimating Method of Contractile State Changes Come From Continuous Isometric Contraction of Skeletal Muscle

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.J.; Lee, S.J. [Wonkwang University, Iksan (Korea)

    2003-01-01

    In this study was proposed that a new estimating method for investigation of contractile state changes which generated from continuous isometric contraction of skeletal muscle. The physiological changes (EMG, ECG) and the psychological changes by CNS(central nervous system) were measured by experiments, while the muscle of subjects contracted continuously with isometric contraction in constant load. The psychological changes were represented as three-step-change named 'fatigue', 'pain' and 'sick(greatly pain)' from oral test, and the method which compared physiological change with psychological change on basis of these three steps was developed. The result of analyzing the physiological signals, EMG and ECG signal changes were observed at the vicinity of judging point in time of psychological changes. Namely, it is supposed that contractile states have three kind of states pattern (stable, fatigue, pain) instead of two states (stable, fatigue). (author). 24 refs., 7 figs.

  19. Measuring the Contractile Response of Isolated Tissue Using an Image Sensor

    Directory of Open Access Journals (Sweden)

    David Díaz-Martín

    2015-04-01

    Full Text Available Isometric or isotonic transducers have traditionally been used to study the contractile/relaxation effects of drugs on isolated tissues. However, these mechanical sensors are expensive and delicate, and they are associated with certain disadvantages when performing experiments in the laboratory. In this paper, a method that uses an image sensor to measure the contractile effect of drugs on blood vessel rings and other luminal organs is presented. The new method is based on an image-processing algorithm, and it provides a fast, easy and non-expensive way to analyze the effects of such drugs. In our tests, we have obtained dose-response curves from rat aorta rings that are equivalent to those achieved with classical mechanic sensors.

  20. Numerical investigation of perforated polymer microcantilever sensor for contractile behavior of cardiomyocytes

    Science.gov (United States)

    Khoa Nguyen, Trieu; Lee, Dong-Weon; Lee, Bong-Kee

    2017-06-01

    In this study, a numerical investigation of microcantilever sensors for detecting the contractile behavior of cardiomyocytes (CMs) was performed. Recently, a novel surface-patterned perforated SU-8 microcantilever sensor has been developed for the preliminary screening of cardiac toxicity. From the contractile motion of the CMs cultured on the microcantilever surface, a macroscopic bending of the microcantilever was obtained, which is considered to reflect a physiological change. As a continuation of the previous research, a novel numerical method based on a surface traction model was proposed and verified to further understand the bending behavior of the microcantilevers. Effects of various factors, including surface traction magnitude, focal area of CMs, and stiffness of microcantilever, on the bending displacement were investigated. From static and transient analyses, the focal area was found to be the most crucial factor. In addition, the current result can provide a design guideline for various micromechanical devices based on the same principle.

  1. Effect of a crude sulfated polysaccharide from Halymenia floresia (Rhodophyta on gastrointestinal smooth muscle contractility

    Directory of Open Access Journals (Sweden)

    José Ronaldo Vasconcelos Graça

    2011-10-01

    Full Text Available The aim of this work was to study the effect of Halymenia floresia (Hf on duodenum contractility, and on experimental protocols of gastric compliance (GC in rats. Fraction Hf2s exhibited a concentration-dependent myocontractile effect (EC50 12.48 µg/ml, and an inhibitory effect after consecutive washing. The contractile response promoted by Hf2s in the duodenum strips was completely inhibited by verapamil, and the effects were prevented in the presence of Ca2+-free medium. The pretreatment with atropine prevented the Hf2s myocontractile effect. Hf2s was also capable to decrease the GC (from 3.8±0.06 to 3.4±0.13 ml, P<0.05, which did not return to basal levels after more 50 min of observation. These results indicated that the algal polysaccharide possessed in vitro and in vivo gastrointestinal effects.

  2. Cell density and actomyosin contractility control the organization of migrating collectives within an epithelium

    Science.gov (United States)

    Loza, Andrew J.; Koride, Sarita; Schimizzi, Gregory V.; Li, Bo; Sun, Sean X.; Longmore, Gregory D.

    2016-01-01

    The mechanisms underlying collective migration are important for understanding development, wound healing, and tumor invasion. Here we focus on cell density to determine its role in collective migration. Our findings show that increasing cell density, as might be seen in cancer, transforms groups from broad collectives to small, narrow streams. Conversely, diminishing cell density, as might occur at a wound front, leads to large, broad collectives with a distinct leader–follower structure. Simulations identify force-sensitive contractility as a mediator of how density affects collectives, and guided by this prediction, we find that the baseline state of contractility can enhance or reduce organization. Finally, we test predictions from these data in an in vivo epithelium by using genetic manipulations to drive collective motion between predicted migratory phases. This work demonstrates how commonly altered cellular properties can prime groups of cells to adopt migration patterns that may be harnessed in health or exploited in disease. PMID:27605707

  3. New insights into roles of acidocalcisomes and contractile vacuole complex in osmoregulation in protists.

    Science.gov (United States)

    Docampo, Roberto; Jimenez, Veronica; Lander, Noelia; Li, Zhu-Hong; Niyogi, Sayantanee

    2013-01-01

    While free-living protists are usually subjected to hyposmotic environments, parasitic protists are also in contact with hyperosmotic habitats. Recent work in one of these parasites, Trypanosoma cruzi, has revealed that its contractile vacuole complex, which usually collects and expels excess water as a mechanism of regulatory volume decrease after hyposmotic stress, has also a role in cell shrinking when the cells are submitted to hyperosmotic stress. Trypanosomes also have an acidic calcium store rich in polyphosphate (polyP), named the acidocalcisome, which is involved in their response to osmotic stress. Here, we review newly emerging insights on the role of acidocalcisomes and the contractile vacuole complex in the cellular response to hyposmotic and hyperosmotic stresses. We also review the current state of knowledge on the composition of these organelles and their other roles in calcium homeostasis and protein trafficking. © 2013, Elsevier Inc. All Rights Reserved.

  4. New Insights into the Roles of Acidocalcisomes and the Contractile Vacuole Complex in Osmoregulation in Protists

    Science.gov (United States)

    Docampo, Roberto; Jimenez, Veronica; Lander, Noelia; Li, Zhu-Hong; Niyogi, Sayantanee

    2013-01-01

    While free-living protists are usually subjected to hyposmotic environments, parasitic protists are also in contact with hyperosmotic habitats. Recent work in one of these parasites, Trypanosoma cruzi, has revealed that its contractile vacuole complex, which usually collects and expels excess water as a mechanism of regulatory volume decrease after hyposmotic stress, has also a role in cell shrinking when the cells are submitted to hyperosmotic stress. Trypanosomes also have an acidic calcium store rich in polyphosphate (polyP), named the acidocalcisome, which is involved in their response to osmotic stress. Here, we review newly emerging insights on the role of acidocalcisomes and the contractile vacuole complex in the cellular response to hyposmotic and hyperosmotic stresses. We also review the current state of knowledge on the composition of these organelles and their other roles in calcium homeostasis and protein trafficking. PMID:23890380

  5. Effects of ageing on single muscle fibre contractile function following short-term immobilisation

    DEFF Research Database (Denmark)

    Hvid, Lars G; Ortenblad, Niels; Aagaard, Per

    2011-01-01

    Very little attention has been given to the combined effects of healthy ageing and short-term disuse on the contractile function of human single muscle fibres. Therefore, the present study investigated the effects of 2 weeks of lower limb cast immobilisation (i.e. disuse) on selected contractile...... IIa: young 18% and old 25%; P selective decrease in Ca(2+) sensitivity in MHC IIa fibres of young (P ....05), respectively. In conclusion, 2 weeks of lower limb immobilisation caused greater impairments in single muscle fibre force and specific force in MHC IIa than MHC I fibres independently of age. In contrast, immobilisation-induced changes in Ca(2+) sensitivity that were dependent on age and MHC isoform....

  6. Levothyroxine treatment generates an abnormal uterine contractility patterns in an in vitro animal model.

    Science.gov (United States)

    Corriveau, Stéphanie; Blouin, Simon; Raiche, Évelyne; Nolin, Marc-Antoine; Rousseau, Éric; Pasquier, Jean-Charles

    2015-12-01

    Abnormal uterine contraction patterns were recently demonstrated in uterine strips from pregnant women treated with Levothyroxine (T4). These abnormalities were correlated with an increased risk of C-section delivery and associated surgical complications. To date, no study has investigated whether uterine contractility is modified by hypothyroidism or T4 treatment. Herein, we analyze the physiological role of T4 on uterine contractions. Female non-pregnant Sprague-Dawley rats ( N  = 22) were used and divided into four groups: 1) control, 2) hypothyroidism, 3) hypothyroidism treated with low T4 doses (20 μg/kg/day) and 4) with high T4 doses (100 μg/kg/day). Hypothyroidism was induced by an iodine-deficient diet. Isometric tension measurements were performed in vitro on myometrium tissues in isolated organ baths. Contractile activity parameters were quantified (amplitude, duration, frequency and area under the curve) using pharmacological tools to assess their effect. Screening of thyroid function confirmed a hypothyroid state for all rats under iodine-free diet to which T4 was subsequently administered to counterbalance hypothyroidism. Results demonstrate that hypothyroidism significantly decreased contractile duration (-17%) and increased contractile frequency (+26%), while high doses of T4 increased duration (+200%) and decreased frequency (-51%). These results thus mimic the pattern of abnormal contractions previously observed in uterine tissue from T4-treated hypothyroid pregnant women. Our data suggest that changes in myometrial reactivity are induced by T4 treatment. Thus, in conjunction with our previous observations on human myometrial strips, management of hypothyroidism should be improved to reduce the rate of C-sections in this group of patients.

  7. Functions of nonmuscle myosin II in assembly of the cellular contractile system.

    Directory of Open Access Journals (Sweden)

    Maria Shutova

    Full Text Available The contractile system of nonmuscle cells consists of interconnected actomyosin networks and bundles anchored to focal adhesions. The initiation of the contractile system assembly is poorly understood structurally and mechanistically, whereas system's maturation heavily depends on nonmuscle myosin II (NMII. Using platinum replica electron microscopy in combination with fluorescence microscopy, we characterized the structural mechanisms of the contractile system assembly and roles of NMII at early stages of this process. We show that inhibition of NMII by a specific inhibitor, blebbistatin, in addition to known effects, such as disassembly of stress fibers and mature focal adhesions, also causes transformation of lamellipodia into unattached ruffles, loss of immature focal complexes, loss of cytoskeleton-associated NMII filaments and peripheral accumulation of activated, but unpolymerized NMII. After blebbistatin washout, assembly of the contractile system begins with quick and coordinated recovery of lamellipodia and focal complexes that occurs before reappearance of NMII bipolar filaments. The initial formation of focal complexes and subsequent assembly of NMII filaments preferentially occurred in association with filopodial bundles and concave actin bundles formed by filopodial roots at the lamellipodial base. Over time, accumulating NMII filaments help to transform the precursor structures, focal complexes and associated thin bundles, into stress fibers and mature focal adhesions. However, semi-sarcomeric organization of stress fibers develops at much slower rate. Together, our data suggest that activation of NMII motor activity by light chain phosphorylation occurs at the cell edge and is uncoupled from NMII assembly into bipolar filaments. We propose that activated, but unpolymerized NMII initiates focal complexes, thus providing traction for lamellipodial protrusion. Subsequently, the mechanical resistance of focal complexes activates a

  8. Influence of genotype on contractile protein differentiation in different bovine muscles during foetal life

    OpenAIRE

    Gagnière , Hélène; Ménissier , François; Geay , Yves; Picard , Brigitte

    2000-01-01

    International audience; The purpose of this work was to compare muscle fibre differentiation in two genetic types: "normal charolais" and double-muscled (DM) "INRA 95" cattles displaying muscle hypertrophy. Six muscles with different contractile and metabolic characteristics in adult animal: Masseter, Diaphragma (Di), Biceps femoris (BF), Longissimus thoracis, Semitendinosus and Cutaneus trunci (CT) were excised from 60 to 260-day-old fœtuses of both genotypes. These muscles present different...

  9. Chronic clenbuterol treatment compromises force production without directly altering skeletal muscle contractile machinery

    Science.gov (United States)

    Py, G; Ramonatxo, C; Sirvent, P; Sanchez, A M J; Philippe, A G; Douillard, A; Galbès, O; Lionne, C; Bonnieu, A; Chopard, A; Cazorla, O; Lacampagne, A; Candau, R B

    2015-01-01

    Clenbuterol is a β2-adrenergic receptor agonist known to induce skeletal muscle hypertrophy and a slow-to-fast phenotypic shift. The aim of the present study was to test the effects of chronic clenbuterol treatment on contractile efficiency and explore the underlying mechanisms, i.e. the muscle contractile machinery and calcium-handling ability. Forty-three 6-week-old male Wistar rats were randomly allocated to one of six groups that were treated with either subcutaneous equimolar doses of clenbuterol (4 mg kg−1 day−1) or saline solution for 9, 14 or 21 days. In addition to the muscle hypertrophy, although an 89% increase in absolute maximal tetanic force (Po) was noted, specific maximal tetanic force (sPo) was unchanged or even depressed in the slow twitch muscle of the clenbuterol-treated rats (P muscle contraction and relaxation force kinetics indicated that clenbuterol treatment significantly reduced the rate constant of force development and the slow and fast rate constants of relaxation in extensor digitorum longus muscle (P fast rate constant of relaxation in soleus muscle (P fibres (fast twitch fibres) from clenbuterol-treated animals demonstrated decreased amplitude after 14 days (−19%, P < 0.01) and 21 days (−25%, P < 0.01). In conclusion, we showed that chronic clenbuterol treatment reduces contractile efficiency, with altered contraction and relaxation kinetics, but without directly altering the contractile machinery. Lower Ca2+ release during contraction could partially explain these deleterious effects. PMID:25656230

  10. Matching of sarcoplasmic reticulum and contractile properties in rat fast- and slow-twitch muscle fibres.

    Science.gov (United States)

    Trinh, Huong H; Lamb, Graham D

    2006-07-01

    1. The twitch characteristics (fast-twitch or slow-twitch) of skeletal muscle fibres are determined not only by the contractile apparatus properties of the fibre, but also by the time-course of Ca2+ release and re-uptake by the sarcoplasmic reticulum (SR). The present study examined, in individual fibres from non-transforming muscle of the rat, whether particular SR properties are matched to the contractile apparatus properties of the fibre, in particular in the case of fibres with fast-twitch contractile apparatus located in a slow-twitch muscle, namely the soleus. 2. Force was recorded in single, mechanically skinned fibres from extensor digitorum longus (EDL), gastrocnemius, peroneus longus and soleus muscles. Using repeated cycles in which the SR was emptied of all releasable Ca2+ and then reloaded, it was possible to determine the relative amount of Ca2+ present in the SR endogenously, the maximum SR capacity and the rate of Ca2+ loading. The sensitivity of the contractile apparatus to Ca2+ and Sr2+ was used to classify the fibres as fast-twitch (FT), slow-twitch (ST) or mixed (fibres examined) and thereby identify the likely troponin C and myosin heavy chain types present. 3. There was no significant difference in SR properties between the groups of FT fibres obtained from the four different muscles, including soleus. Despite some overlap in the SR properties of individual fibres between the FT and ST groups, the properties of the FT fibres in all four muscles studied were significantly different from those of the ST and mixed fibres. 4. In general, in FT fibres the SR had a larger capacity and the endogenous Ca2+ content was a relatively lower percentage of maximum compared with ST fibres. Importantly, in terms of their SR properties, FT fibres from soleus muscle more closely resembled FT fibres from other muscles than they did ST fibres from soleus muscle.

  11. Myosin phosphorylation improves contractile economy of mouse fast skeletal muscle during staircase potentiation.

    Science.gov (United States)

    Bunda, Jordan; Gittings, William; Vandenboom, Rene

    2018-01-30

    Phosphorylation of the myosin regulatory light chain (RLC) by skeletal myosin light chain kinase (skMLCK) potentiates rodent fast twitch muscle but is an ATP-requiring process. Our objective was to investigate the effect of skMLCK-catalyzed RLC phosphorylation on the energetic cost of contraction and the contractile economy (ratio of mechanical output to metabolic input) of mouse fast twitch muscle in vitro (25°C). To this end, extensor digitorum longus (EDL) muscles from wild-type (WT) and from skMLCK-devoid (skMLCK -/- ) mice were subjected to repetitive low-frequency stimulation (10 Hz for 15 s) to produce staircase potentiation of isometric twitch force, after which muscles were quick frozen for determination of high-energy phosphate consumption (HEPC). During stimulation, WT muscles displayed significant potentiation of isometric twitch force while skMLCK -/- muscles did not (i.e. 23% versus 5% change, respectively). Consistent with this, RLC phosphorylation was increased ∼3.5-fold from the unstimulated control value in WT but not in skMLCK -/- muscles. Despite these differences, the HEPC of WT muscles was not greater than that of skMLCK -/- muscles. As a result of the increased contractile output relative to HEPC, the calculated contractile economy of WT muscles was greater than that of skMLCK -/- muscles. Thus, our results suggest that skMLCK-catalyzed phosphorylation of the myosin RLC increases the contractile economy of WT mouse EDL muscle compared with skMLCK -/- muscles without RLC phosphorylation. © 2018. Published by The Company of Biologists Ltd.

  12. Cardiac-specific overexpression of catalase attenuates lipopolysaccharide-induced myocardial contractile dysfunction: role of autophagy.

    Science.gov (United States)

    Turdi, Subat; Han, Xuefeng; Huff, Anna F; Roe, Nathan D; Hu, Nan; Gao, Feng; Ren, Jun

    2012-09-15

    Lipopolysaccharide (LPS) from gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complications in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged with LPS (6 mg/kg) and cardiac function was evaluated. Levels of oxidative stress, autophagy, apoptosis, and protein damage were examined using fluorescence microscopy, Western blot, TUNEL assay, caspase-3 activity, and carbonyl formation. A Kaplan-Meier curve was constructed for survival after LPS treatment. Our results revealed a lower mortality in catalase mice compared with FVB mice after LPS challenge. LPS injection led to depressed cardiac contractile capacity as evidenced by echocardiography and cardiomyocyte contractile function, the effect of which was ablated by catalase overexpression. LPS treatment induced elevated TNF-α level, autophagy, apoptosis (TUNEL, caspase-3 activation, cleaved caspase-3), production of ROS and O(2)(-), and protein carbonyl formation, the effects of which were significantly attenuated by catalase overexpression. Electron microscopy revealed focal myocardial damage characterized by mitochondrial injury after LPS treatment, which was less severe in catalase mice. Interestingly, LPS-induced cardiomyocyte contractile dysfunction was prevented by the antioxidant N-acetylcysteine and the autophagy inhibitor 3-methyladenine. Taken together, our data revealed that catalase protects against LPS-induced cardiac dysfunction and mortality, which may be associated with inhibition of oxidative stress and autophagy. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Cardiac-Specific Overexpression of Catalase Attenuates Lipopolysaccharide-Induced Myocardial Contractile Dysfunction: Role of Autophagy

    OpenAIRE

    Turdi, Subat; Han, Xuefeng; Huff, Anna F.; Roe, Nathan D.; Hu, Nan; Gao, Feng; Ren, Jun

    2012-01-01

    Lipopolysaccharide (LPS) from Gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complication in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged ...

  14. A thermodynamical model for stress-fiber organization in contractile cells

    OpenAIRE

    Foucard, Louis; Vernerey, Franck J.

    2012-01-01

    Cell mechanical adaptivity to external stimuli is vital to many of its biological functions. A critical question is therefore to understand the formation and organization of the stress fibers from which emerge the cell’s mechanical properties. By accounting for the mechanical aspects and the viscoelastic behavior of stress fibers, we here propose a thermodynamic model to predict the formation and orientation of stress fibers in contractile cells subjected to constant or cyclic stretch and dif...

  15. Cardiac-Specific Overexpression of Catalase Attenuates Lipopolysaccharide-Induced Myocardial Contractile Dysfunction: Role of Autophagy

    Science.gov (United States)

    Turdi, Subat; Han, Xuefeng; Huff, Anna F.; Roe, Nathan D.; Hu, Nan; Gao, Feng; Ren, Jun

    2012-01-01

    Lipopolysaccharide (LPS) from Gram-negative bacteria is a major initiator of sepsis, leading to cardiovascular collapse. Accumulating evidence has indicated a role of reactive oxygen species (ROS) in cardiovascular complication in sepsis. This study was designed to examine the effect of cardiac-specific overexpression of catalase in LPS-induced cardiac contractile dysfunction and the underlying mechanism(s) with a focus on autophagy. Catalase transgenic and wild-type FVB mice were challenged with LPS (6 mg/kg) and cardiac function was evaluated. Levels of oxidative stress, autophagy, apoptosis and protein damage were examined using fluorescence microscopy, Western blot, TUNEL assay, caspase-3 activity and carbonyl formation. Kaplan-Meier curve was constructed for survival following LPS treatment. Our results revealed a lower mortality in catalase mice compared with FVB mice following LPS challenge. LPS injection led to depressed cardiac contractile capacity as evidenced by echocardiography and cardiomyocyte contractile function, the effect of which was ablated by catalase overexpression. LPS treatment induced elevated TNF-α level, autophagy, apoptosis (TUNEL, caspase-3 activation, cleaved caspase-3), production of ROS and O2−, and protein carbonyl formation, the effects of which were significantly attenuated by catalase overexpression. Electron microscopy revealed focal myocardial damage characterized by mitochondrial injury following LPS treatment, which was less severe in catalase mice. Interestingly, LPS-induced cardiomyocyte contractile dysfunction was prevented by antioxidant NAC and the autophagy inhibitor 3-methyladenine. Taken together, our data revealed that catalase protects against LPS-induced cardiac dysfunction and mortality, which may be associated with inhibition of oxidative stress and autophagy. PMID:22902401

  16. Cardiac myofibrillar contractile properties during the progression from hypertension to decompensated heart failure.

    Science.gov (United States)

    Hanft, Laurin M; Emter, Craig A; McDonald, Kerry S

    2017-07-01

    Heart failure arises, in part, from a constellation of changes in cardiac myocytes including remodeling, energetics, Ca 2+ handling, and myofibrillar function. However, little is known about the changes in myofibrillar contractile properties during the progression from hypertension to decompensated heart failure. The aim of the present study was to provide a comprehensive assessment of myofibrillar functional properties from health to heart disease. A rodent model of uncontrolled hypertension was used to test the hypothesis that myocytes in compensated hearts exhibit increased force, higher rates of force development, faster loaded shortening, and greater power output; however, with progression to overt heart failure, we predicted marked depression in these contractile properties. We assessed contractile properties in skinned cardiac myocyte preparations from left ventricles of Wistar-Kyoto control rats and spontaneous hypertensive heart failure (SHHF) rats at ~3, ~12, and >20 mo of age to evaluate the time course of myofilament properties associated with normal aging processes compared with myofilaments from rats with a predisposition to heart failure. In control rats, the myofilament contractile properties were virtually unchanged throughout the aging process. Conversely, in SHHF rats, the rate of force development, loaded shortening velocity, and power all increased at ~12 mo and then significantly fell at the >20-mo time point, which coincided with a decrease in left ventricular fractional shortening. Furthermore, these changes occurred independent of changes in β-myosin heavy chain but were associated with depressed phosphorylation of myofibrillar proteins, and the fall in loaded shortening and peak power output corresponded with the onset of clinical signs of heart failure. NEW & NOTEWORTHY This novel study systematically examined the power-generating capacity of cardiac myofilaments during the progression from hypertension to heart disease. Previously

  17. Robust gap repair in the contractile ring ensures timely completion of cytokinesis.

    OpenAIRE

    Silva, AM; Osório, DS; Pereira, AJ; Maiato, H; Pinto, IM; Rubinstein, B; Gassmann, R; Telley, IA; Carvalho, AX

    2016-01-01

    Cytokinesis in animal cells requires the constriction of an actomyosin contractile ring, whose architecture and mechanism remain poorly understood. We use laser microsurgery to explore the biophysical properties of constricting rings in Caenorhabditis elegans embryos. Laser cutting causes rings to snap open. However, instead of disintegrating, ring topology recovers and constriction proceeds. In response to severing, a finite gap forms and is repaired by recruitment of new material in an acti...

  18. Changes in contractile properties of muscles receiving repeat injections of botulinum toxin (Botox).

    Science.gov (United States)

    Fortuna, Rafael; Vaz, Marco Aurélio; Youssef, Aliaa Rehan; Longino, David; Herzog, Walter

    2011-01-04

    Botulinum toxin type A (BTX-A) is a frequently used therapeutic tool to denervate muscles in the treatment of neuromuscular disorders. Although considered safe by the US Food and Drug Administration, BTX-A can produce adverse effects in target and non-target muscles. With an increased use of BTX-A for neuromuscular disorders, the effects of repeat injections of BTX-A on strength, muscle mass and structure need to be known. Therefore, the purpose of this study was to investigate the changes in strength, muscle mass and contractile material in New Zealand White (NZW) rabbits. Twenty NZW rabbits were divided into 4 groups: control and 1, 3 and 6 months of unilateral, repeat injections of BTX-A into the quadriceps femoris. Outcome measures included knee extensor torque, muscle mass and the percentage of contractile material in the quadriceps muscles of the target and non-injected contralateral hindlimbs. Strength in the injected muscles was reduced by 88%, 89% and 95% in the 1, 3 and 6 months BTX-A injected hindlimbs compared to controls. Muscle mass was reduced by 50%, 42% and 31% for the vastus lateralis (VL), rectus femoris (RF) and vastus medialis (VM), respectively, at 1 month, by 68%, 51% and 50% at 3 months and by 76%, 44% and 13% at 6 months. The percentage of contractile material was reduced for the 3 and 6 months animals to 80-64%, respectively, and was replaced primarily by fat. Similar, but less pronounced results were also observed for the quadriceps muscles of the contralateral hindlimbs, suggesting that repeat BTX-A injections cause muscle atrophy and loss of contractile tissue in target muscles and also in non-target muscles that are far removed from the injection site. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. UN MODELO CAUSAL DE COMPETITIVIDAD EMPRESARIAL PLANTEADO DESDE LA VBR: CAPACIDADES DIRECTIVAS, DE INNOVACIÓN, MARKETING Y CALIDAD

    Directory of Open Access Journals (Sweden)

    Martínez Santa María, R.

    2010-01-01

    Full Text Available El propósito de esta investigación es desarrollar un modelo explicativo de la competitividad empresarial a partir de factores internos a la empresa. Para ello se identifican los factores de competitividad más importantes en el caso de las empresas manufactureras vascas, así como las variables que permiten caracterizarlos, utilizando técnicas cualitativas basadas en entrevistas con directivos. Los factores resultantes son las capacidades directivas, las capacidades de innovación, las capacidades de marketing y las capacidades de calidad. Tras analizar estos factores bajo la Visión de la empresa Basada en Recursos (VBR, y definir sus escalas de medida, se plantea un modelo causal que relaciona cada uno de ellos con la competividad de la empresa. Este modelo otorga una importancia especial a las capacidades directivas al plantear este factor como precedente del resto de capacidades de la empresa. El modelo es contrastado a través de la técnica de modelado con ecuaciones estructurales utilizando una muestra representativa de la población de empresas manufactureras vascas formada por 861 empresas.

  20. Uso do Verapamil em Gestantes Hipertensas Crônicas: análise do Fluxo das Artérias Uterinas e Umbilical Use of Verapamil in Chronic Hypertensive Pregnant Women: flow Analysis of Uterine Arteries and Umbilical Artery

    Directory of Open Access Journals (Sweden)

    Marcus Jose do Amaral Vasconcellos

    2000-06-01

    Full Text Available Objetivo: este trabalho, utilizando verapamil, um bloqueador dos canais lentos de cálcio, constituiu ensaio clínico randomizado, duplo-cego e placebo controlado, e objetivou procurar variação do fluxo uteroplacentário e fetoplacentário durante uso oral crônico do fármaco em gestantes com hipertensão crônica leve para moderada. Métodos: 123 pacientes divididas em dois grupos: grupo estudo (n = 61, submetidas a 240 mg/dia de verapamil, e grupo controle (n = 62, submetidas ao placebo. As pacientes randomizadas em grupos de quatro utilizaram a medicação ou placebo durante trinta dias. Um exame do fluxo das artérias uterinas e da artéria umbilical pela dopplervelocimetria foi registrado. Pelo cálculo da média e desvio padrão, foram comparados os valores dos índices de resistência (IR e pulsatilidade (IP e da relação sístole/diástole (A/B das artérias em estudo após administração dos comprimidos. Resultados: o grupo verapamil apresentou os seguintes valores médios para as artérias uterinas: IR = 0,82 (0,28, IP de 1,06 (0,12 e A/B de 2,42 (0,51. O grupo placebo mostrou: IR de 0,75 (0,35, IP de 1,00 (0,18 e A/B de 2,30 (0,38. Quando analisada a artéria umbilical, os valores foram para o grupo verapamil: IR = 0,73 (0,12, IP = 1,04 (0,13 e A/B = 2,94 (0,32. No grupo placebo, IR = 0,70 (0,14, IP = 1,03 (0,07 e A/B = 3,02 (0,78. A análise estatística das diferenças das médias por meio da razão F mostrou não haver diferença entre os dois grupos avaliados. Conclusão: este trabalho referenda o uso do verapamil entre gestantes com hipertensão crônica (leve para moderada, pois não oferece prejuízos no fluxo uteroplacentário e fetoplacentário.Purpose: this study, using verapamil, a slow calcium channel blocker, was a randomized, clinical, double blind and placebo controlled trial, whose objective was to observe if there was a uteroplacental and fetoplacental flow variation during its chronic oral use. Methods: 123

  1. Impact of tamsulosin and nifedipine on contractility of pregnant rat ureters in vitro.

    Science.gov (United States)

    Haddad, Lisette; Corriveau, Stéphanie; Rousseau, Eric; Blouin, Simon; Pasquier, Jean-Charles; Ponsot, Yves; Roy-Lacroix, Marie-Ève

    2018-01-01

    To evaluate the in vitro effect of tamsulosin and nifedipine on the contractility of pregnant rat ureters and to perform quantitative analysis of the pharmacological effects. Medical expulsive therapy (MET) is commonly used to treat urolithiasis. However, this treatment is seldom used in pregnant women since no studies support this practice. This was an in vitro study on animal tissue derived from pregnant Sprague-Dawley rats. A total of 124 ureteral segments were mounted in an organ bath system and contractile response to methacholine (MCh) was assessed. Tamsulosin or nifedipine were added at cumulative concentrations (0.001-1 μM). The area under the curve (AUC) from isometric tension measurements was calculated. The effect of pharmacological agents and the respective controls were assessed by calculating the AUC for each 5-min interval. Statistical analyses were performed using the Mann-Whitney-Wilcoxon nonparametric test. Both drugs displayed statistically significant inhibitory activity at concentrations of 0.1 and 1 μM for tamsulosin and 1 μM for nifedipine when calculated as the AUC as compared to DMSO controls. Tamsulosin and nifedipine directly inhibit MCh-induced contractility of pregnant rat ureters. Further work is needed to determine the clinical efficacy of these medications for MET in pregnancy.

  2. PTP1B triggers integrin-mediated repression of myosin activity and modulates cell contractility

    Directory of Open Access Journals (Sweden)

    Ana E. González Wusener

    2016-01-01

    Full Text Available Cell contractility and migration by integrins depends on precise regulation of protein tyrosine kinase and Rho-family GTPase activities in specific spatiotemporal patterns. Here we show that protein tyrosine phosphatase PTP1B cooperates with β3 integrin to activate the Src/FAK signalling pathway which represses RhoA-myosin-dependent contractility. Using PTP1B null (KO cells and PTP1B reconstituted (WT cells, we determined that some early steps following cell adhesion to fibronectin and vitronectin occurred robustly in WT cells, including aggregation of β3 integrins and adaptor proteins, and activation of Src/FAK-dependent signalling at small puncta in a lamellipodium. However, these events were significantly impaired in KO cells. We established that cytoskeletal strain and cell contractility was highly enhanced at the periphery of KO cells compared to WT cells. Inhibition of the Src/FAK signalling pathway or expression of constitutive active RhoA in WT cells induced a KO cell phenotype. Conversely, expression of constitutive active Src or myosin inhibition in KO cells restored the WT phenotype. We propose that this novel function of PTP1B stimulates permissive conditions for adhesion and lamellipodium assembly at the protruding edge during cell spreading and migration.

  3. PTP1B triggers integrin-mediated repression of myosin activity and modulates cell contractility

    Science.gov (United States)

    González Wusener, Ana E.; González, Ángela; Nakamura, Fumihiko; Arregui, Carlos O.

    2016-01-01

    ABSTRACT Cell contractility and migration by integrins depends on precise regulation of protein tyrosine kinase and Rho-family GTPase activities in specific spatiotemporal patterns. Here we show that protein tyrosine phosphatase PTP1B cooperates with β3 integrin to activate the Src/FAK signalling pathway which represses RhoA-myosin-dependent contractility. Using PTP1B null (KO) cells and PTP1B reconstituted (WT) cells, we determined that some early steps following cell adhesion to fibronectin and vitronectin occurred robustly in WT cells, including aggregation of β3 integrins and adaptor proteins, and activation of Src/FAK-dependent signalling at small puncta in a lamellipodium. However, these events were significantly impaired in KO cells. We established that cytoskeletal strain and cell contractility was highly enhanced at the periphery of KO cells compared to WT cells. Inhibition of the Src/FAK signalling pathway or expression of constitutive active RhoA in WT cells induced a KO cell phenotype. Conversely, expression of constitutive active Src or myosin inhibition in KO cells restored the WT phenotype. We propose that this novel function of PTP1B stimulates permissive conditions for adhesion and lamellipodium assembly at the protruding edge during cell spreading and migration. PMID:26700725

  4. Changes of contractile responses due to simulated weightlessness in rat soleus muscle

    Science.gov (United States)

    Elkhammari, A.; Noireaud, J.; Léoty, C.

    1994-08-01

    Some contractile and electrophysiological properties of muscle fibers isolated from the slow-twitch soleus (SOL) and fast-twitch extensor digitorum longus (EDL) muscles of rats were compared with those measured in SOL muscles from suspended rats. In suspendede SOL (21 days of tail-suspension) membrane potential (Em), intracellular sodium activity (aiNa) and the slope of the relationship between Em and log [K]o were typical of fast-twitch muscles. The relation between the maximal amplitude of K-contractures vs Em was steeper for control SOL than for EDL and suspended SOL muscles. After suspension, in SOL muscles the contractile threshold and the inactivation curves for K-contractures were shifted to more positive Em. Repriming of K-contractures was unaffected by suspencion. The exposure of isolated fibers to perchlorate (ClO4-)-containing (6-40 mM) solutions resulted ina similar concentration-dependent shift to more negative Em of activation curves for EDL and suspended SOL muscles. On exposure to a Na-free TEA solution, SOL from control and suspended rats, in contrast to EDL muscles, generated slow contractile responses. Suspended SOL showed a reduced sensitivity to the contracture-producing effect of caffeine compared to control muscles. These results suggested that the modification observed due to suspension could be encounted by changes in the characteristics of muscle fibers from slow to fast-twitch type.

  5. A human in vitro model of Duchenne muscular dystrophy muscle formation and contractility.

    Science.gov (United States)

    Nesmith, Alexander P; Wagner, Matthew A; Pasqualini, Francesco S; O'Connor, Blakely B; Pincus, Mark J; August, Paul R; Parker, Kevin Kit

    2016-10-10

    Tongue weakness, like all weakness in Duchenne muscular dystrophy (DMD), occurs as a result of contraction-induced muscle damage and deficient muscular repair. Although membrane fragility is known to potentiate injury in DMD, whether muscle stem cells are implicated in deficient muscular repair remains unclear. We hypothesized that DMD myoblasts are less sensitive to cues in the extracellular matrix designed to potentiate structure-function relationships of healthy muscle. To test this hypothesis, we drew inspiration from the tongue and engineered contractile human muscle tissues on thin films. On this platform, DMD myoblasts formed fewer and smaller myotubes and exhibited impaired polarization of the cell nucleus and contractile cytoskeleton when compared with healthy cells. These structural aberrations were reflected in their functional behavior, as engineered tongues from DMD myoblasts failed to achieve the same contractile strength as healthy tongue structures. These data suggest that dystrophic muscle may fail to organize with respect to extracellular cues necessary to potentiate adaptive growth and remodeling. © 2016 Nesmith et al.

  6. Carboxyl-terminal-dependent recruitment of nonmuscle myosin II to megakaryocyte contractile ring during polyploidization.

    Science.gov (United States)

    Badirou, Idinath; Pan, Jiajia; Legrand, Céline; Wang, Aibing; Lordier, Larissa; Boukour, Siham; Roy, Anita; Vainchenker, William; Chang, Yunhua

    2014-10-16

    Endomitosis is a unique megakaryocyte (MK) differentiation process that is the consequence of a late cytokinesis failure associated with a contractile ring defect. Evidence from in vitro studies has revealed the distinct roles of 2 nonmuscle myosin IIs (NMIIs) on MK endomitosis: only NMII-B (MYH10), but not NMII-A (MYH9), is localized in the MK contractile ring and implicated in mitosis/endomitosis transition. Here, we studied 2 transgenic mouse models in which nonmuscle myosin heavy chain (NMHC) II-A was genetically replaced either by II-B or by a chimeric NMHCII that combined the head domain of II-A with the rod and tail domains of II-B. This study provides in vivo evidence on the specific role of NMII-B on MK polyploidization. It demonstrates that the carboxyl-terminal domain of the heavy chains determines myosin II localization to the MK contractile ring and is responsible for the specific role of NMII-B in MK polyploidization.

  7. A contractile and counterbalancing adhesion system controls the 3D shape of crawling cells.

    Science.gov (United States)

    Burnette, Dylan T; Shao, Lin; Ott, Carolyn; Pasapera, Ana M; Fischer, Robert S; Baird, Michelle A; Der Loughian, Christelle; Delanoe-Ayari, Helene; Paszek, Matthew J; Davidson, Michael W; Betzig, Eric; Lippincott-Schwartz, Jennifer

    2014-04-14

    How adherent and contractile systems coordinate to promote cell shape changes is unclear. Here, we define a counterbalanced adhesion/contraction model for cell shape control. Live-cell microscopy data showed a crucial role for a contractile meshwork at the top of the cell, which is composed of actin arcs and myosin IIA filaments. The contractile actin meshwork is organized like muscle sarcomeres, with repeating myosin II filaments separated by the actin bundling protein α-actinin, and is mechanically coupled to noncontractile dorsal actin fibers that run from top to bottom in the cell. When the meshwork contracts, it pulls the dorsal fibers away from the substrate. This pulling force is counterbalanced by the dorsal fibers' attachment to focal adhesions, causing the fibers to bend downward and flattening the cell. This model is likely to be relevant for understanding how cells configure themselves to complex surfaces, protrude into tight spaces, and generate three-dimensional forces on the growth substrate under both healthy and diseased conditions.

  8. Local 3D matrix microenvironment regulates cell migration through spatiotemporal dynamics of contractility-dependent adhesions

    Science.gov (United States)

    Doyle, Andrew D.; Carvajal, Nicole; Jin, Albert; Matsumoto, Kazue; Yamada, Kenneth M.

    2015-11-01

    The physical properties of two-dimensional (2D) extracellular matrices (ECMs) modulate cell adhesion dynamics and motility, but little is known about the roles of local microenvironmental differences in three-dimensional (3D) ECMs. Here we generate 3D collagen gels of varying matrix microarchitectures to characterize their regulation of 3D adhesion dynamics and cell migration. ECMs containing bundled fibrils demonstrate enhanced local adhesion-scale stiffness and increased adhesion stability through balanced ECM/adhesion coupling, whereas highly pliable reticular matrices promote adhesion retraction. 3D adhesion dynamics are locally regulated by ECM rigidity together with integrin/ECM association and myosin II contractility. Unlike 2D migration, abrogating contractility stalls 3D migration regardless of ECM pore size. We find force is not required for clustering of activated integrins on 3D native collagen fibrils. We propose that efficient 3D migration requires local balancing of contractility with ECM stiffness to stabilize adhesions, which facilitates the detachment of activated integrins from ECM fibrils.

  9. Cellular contractility and substrate elasticity: a numerical investigation of the actin cytoskeleton and cell adhesion.

    Science.gov (United States)

    Ronan, William; Deshpande, Vikram S; McMeeking, Robert M; McGarry, J Patrick

    2014-04-01

    Numerous experimental studies have established that cells can sense the stiffness of underlying substrates and have quantified the effect of substrate stiffness on stress fibre formation, focal adhesion area, cell traction, and cell shape. In order to capture such behaviour, the current study couples a mixed mode thermodynamic and mechanical framework that predicts focal adhesion formation and growth with a material model that predicts stress fibre formation, contractility, and dissociation in a fully 3D implementation. Simulations reveal that SF contractility plays a critical role in the substrate-dependent response of cells. Compliant substrates do not provide sufficient tension for stress fibre persistence, causing dissociation of stress fibres and lower focal adhesion formation. In contrast, cells on stiffer substrates are predicted to contain large amounts of dominant stress fibres. Different levels of cellular contractility representative of different cell phenotypes are found to alter the range of substrate stiffness that cause the most significant changes in stress fibre and focal adhesion formation. Furthermore, stress fibre and focal adhesion formation evolve as a cell spreads on a substrate and leading to the formation of bands of fibres leading from the cell periphery over the nucleus. Inhibiting the formation of FAs during cell spreading is found to limit stress fibre formation. The predictions of this mutually dependent material-interface framework are strongly supported by experimental observations of cells adhered to elastic substrates and offer insight into the inter-dependent biomechanical processes regulating stress fibre and focal adhesion formation.

  10. EXERCISE PERFORMANCE AND MUSCLE CONTRACTILE PROPERTIES AFTER CREATINE MONOHYDRATE SUPPLEMENTATION IN AEROBIC-ANAEROBIC TRAINING RATS

    Directory of Open Access Journals (Sweden)

    Nickolay Boyadjiev

    2007-12-01

    Full Text Available The purpose of this study was to investigate the effects of creatine monohydrate supplementation on exercise performance and contractile variables in aerobic-anaerobic training rats. Twenty 90-day-old male Sprague Dawley rats were divided into two groups - creatine (Cr and controls (K. The creatine group received creatine monohydrate as a nutritional supplement, whereas the control group was given placebo. Both groups were trained 5 days a week on a treadmill for 20 days in a mixed (aerobic-anaerobic metabolic working regimen (27 m·min-1, 15% elevation for 40 min. The exercise performance (sprint-test, contractile properties (m. tibialis anterior, oxidative enzyme activity (SDH, LDH, NADH2 in m. soleus and blood hematological and chemical variables were assessed in the groups at the end of the experiment. It was found out that creatine supplementation improved the exercise performance after 20 days of administration in a dose of 60 mg per day on the background of a mixed (aerobic-anaerobic exercise training. At the end of the trial the Cr-group demonstrated better values for the variables which characterize the contractile properties of m. tibialis anterior containing predominantly types IIA and IIB muscle fibers. On the other hand, a higher oxidative capacity was found out in m. soleus (type I muscle fibers as a result of 20-day creatine supplementation. No side effects of creatine monohydrate supplementation were assessed by the hematological and blood biochemical indices measured in this study

  11. Robust gap repair in the contractile ring ensures timely completion of cytokinesis.

    Science.gov (United States)

    Silva, Ana M; Osório, Daniel S; Pereira, Antonio J; Maiato, Helder; Pinto, Inês Mendes; Rubinstein, Boris; Gassmann, Reto; Telley, Ivo Andreas; Carvalho, Ana Xavier

    2016-12-19

    Cytokinesis in animal cells requires the constriction of an actomyosin contractile ring, whose architecture and mechanism remain poorly understood. We use laser microsurgery to explore the biophysical properties of constricting rings in Caenorhabditis elegans embryos. Laser cutting causes rings to snap open. However, instead of disintegrating, ring topology recovers and constriction proceeds. In response to severing, a finite gap forms and is repaired by recruitment of new material in an actin polymerization-dependent manner. An open ring is able to constrict, and rings repair from successive cuts. After gap repair, an increase in constriction velocity allows cytokinesis to complete at the same time as controls. Our analysis demonstrates that tension in the ring increases while net cortical tension at the site of ingression decreases throughout constriction and suggests that cytokinesis is accomplished by contractile modules that assemble and contract autonomously, enabling local repair of the actomyosin network. Consequently, cytokinesis is a highly robust process impervious to discontinuities in contractile ring structure. © 2016 Silva et al.

  12. Adaptive responses of mouse skeletal muscle to contractile activity: The effect of age.

    Science.gov (United States)

    Vasilaki, A; McArdle, F; Iwanejko, L M; McArdle, A

    2006-11-01

    This study has characterised the time course of two major transcriptional adaptive responses to exercise (changes in antioxidant defence enzyme activity and heat shock protein (HSP) content) in muscles of adult and old male mice following isometric contractions and has examined the mechanisms involved in the age-related reduction in transcription factor activation. Muscles of B6XSJL mice were subjected to isometric contractions and analysed for antioxidant defence enzyme activities, heat shock protein content and transcription factor DNA binding activity. Data demonstrated a significant increase in superoxide dismutase (SOD) and catalase activity and HSP content of muscles of adult mice following contractile activity which was associated with increased activation of the transcription factors, nuclear factor-kappaB (NF-kappaB), activator protein-1 (AP-1) and heat shock factor (HSF) following contractions. Significant increases in SOD and catalase activity and heat shock cognate (HSC70) content were seen in quiescent muscles of old mice. The increase in antioxidant defence enzyme activity following contractile activity seen in muscles of adult mice was not seen in muscles of old mice and this was associated with a failure to fully activate NF-kappaB and AP-1 following contractions. In contrast, although the production of HSPs was also reduced in muscles of old mice following contractile activity compared with muscles of adult mice following contractions, this was not due to a gross reduction in the DNA binding activity of HSF.

  13. Galectin-3 and fibulin-1 in systolic heart failure - relation to glucose metabolism and left ventricular contractile reserve

    OpenAIRE

    Holmager, Pernille; Egstrup, Michael; Gustafsson, Ida; Schou, Morten; Dahl, Jordi S.; Rasmussen, Lars Melholt; M?ller, Jacob E.; Tuxen, Christian; Faber, Jens; Kistorp, Caroline

    2017-01-01

    Background: Heart failure (HF) patients with diabetes (DM) have an adverse prognosis and reduced functional capacity, which could be associated with cardiac fibrosis, increased chamber stiffness and reduced left ventricular (LV) contractile reserve. Galectin-3 (Gal-3) and fibulin-1 are circulating biomarkers potentially reflecting cardiac fibrosis. We hypothesize that plasma levels of Gal-3 and fibulin-1 are elevated in HF patients with DM and are associated with reduced LV contractile reserv...

  14. A global, myosin light chain kinase-dependent increase in myosin II contractility accompanies the metaphase-anaphase transition in sea urchin eggs.

    Science.gov (United States)

    Lucero, Amy; Stack, Christianna; Bresnick, Anne R; Shuster, Charles B

    2006-09-01

    Myosin II is the force-generating motor for cytokinesis, and although it is accepted that myosin contractility is greatest at the cell equator, the temporal and spatial cues that direct equatorial contractility are not known. Dividing sea urchin eggs were placed under compression to study myosin II-based contractile dynamics, and cells manipulated in this manner underwent an abrupt, global increase in cortical contractility concomitant with the metaphase-anaphase transition, followed by a brief relaxation and the onset of furrowing. Prefurrow cortical contractility both preceded and was independent of astral microtubule elongation, suggesting that the initial activation of myosin II preceded cleavage plane specification. The initial rise in contractility required myosin light chain kinase but not Rho-kinase, but both signaling pathways were required for successful cytokinesis. Last, mobilization of intracellular calcium during metaphase induced a contractile response, suggesting that calcium transients may be partially responsible for the timing of this initial contractile event. Together, these findings suggest that myosin II-based contractility is initiated at the metaphase-anaphase transition by Ca2+-dependent myosin light chain kinase (MLCK) activity and is maintained through cytokinesis by both MLCK- and Rho-dependent signaling. Moreover, the signals that initiate myosin II contractility respond to specific cell cycle transitions independently of the microtubule-dependent cleavage stimulus.

  15. A Global, Myosin Light Chain Kinase-dependent Increase in Myosin II Contractility Accompanies the Metaphase–Anaphase Transition in Sea Urchin Eggs

    Science.gov (United States)

    Lucero, Amy; Stack, Christianna; Bresnick, Anne R.

    2006-01-01

    Myosin II is the force-generating motor for cytokinesis, and although it is accepted that myosin contractility is greatest at the cell equator, the temporal and spatial cues that direct equatorial contractility are not known. Dividing sea urchin eggs were placed under compression to study myosin II-based contractile dynamics, and cells manipulated in this manner underwent an abrupt, global increase in cortical contractility concomitant with the metaphase–anaphase transition, followed by a brief relaxation and the onset of furrowing. Prefurrow cortical contractility both preceded and was independent of astral microtubule elongation, suggesting that the initial activation of myosin II preceded cleavage plane specification. The initial rise in contractility required myosin light chain kinase but not Rho-kinase, but both signaling pathways were required for successful cytokinesis. Last, mobilization of intracellular calcium during metaphase induced a contractile response, suggesting that calcium transients may be partially responsible for the timing of this initial contractile event. Together, these findings suggest that myosin II-based contractility is initiated at the metaphase–anaphase transition by Ca2+-dependent myosin light chain kinase (MLCK) activity and is maintained through cytokinesis by both MLCK- and Rho-dependent signaling. Moreover, the signals that initiate myosin II contractility respond to specific cell cycle transitions independently of the microtubule-dependent cleavage stimulus. PMID:16837551

  16. Capacidad Predictiva de Modelos de Insolvencia con Base en Números Contables y Datos Descriptivos

    Directory of Open Access Journals (Sweden)

    Júlio Orestes da Silva

    2012-01-01

    Full Text Available En el Brasil la pesquisa sobre modelos de previsión de insolvencia se inició en la década de 1970, siendo que lamayor parte de los trabajos hizo uso del Análisis Discriminante como herramienta estadística del modelo. En losúltimos años, se buscó verificar si es posible prever la insolvencia de las empresas utilizando datos descriptivoscontenidos en los informes de las organizaciones. Así, este estudio tiene como objetivo verificar la capacidad dealgunos modelos de previsión de insolvencia en prever la discontinuidad de empresas brasileñas que decretaron quiebra. La pesquisa se caracteriza como descriptiva y posee abordaje cuantitativo, realizado por medio de pesquisadocumental. La muestra totalizó 13 empresas que decretaron quiebra entre los años de 1997 y 2003. Los resultadosindican que la mayoría de los modelos de previsión de quiebra testados presentó resultados elevados deprevisiones correctas. Los modelos de previsión de discontinuidad con base en informes descriptivos obtuvieronen media más previsiones asertivas en relación a la capacidad de prever la quiebra de las empresas. Esos descubrimientosdemuestran que, a pesar de que algunas pesquisas apunten hacia la falta de validez de predictores creadosen realidades empresariales diferentes, algunos modelos todavía poseen buena capacidad de previsión de insolvencia.Se concluye que tanto los modelos de previsión de insolvencia con base en números contables en relación alos modelos que se utilizan datos de informes descriptivos pueden prever la discontinuidad de las organizaciones.Por fin, se puede inferir que la mayoría de los modelos de previsión de quiebra que hacen uso de números contablespueden ser funcionales y capaces de prever la discontinuidad de las organizaciones.

  17. Incubadoras de empresas e o desenvolvimento de capacidades em empresas incubadas

    Directory of Open Access Journals (Sweden)

    José Eduardo Storopoli

    2013-04-01

    Full Text Available DOI: http://dx.doi.org/10.5007/2175-8077.2013v15n35p36   No Brasil, as incubadoras de empresa vêm-se consolidando ao longo dos anos com contribuições importantes para o processo de desenvolvimento de ideias que se transformam em negócios e também de empreendedores que se tornam empresários. As incubadoras permitem que as capacidades e recursos disponíveis deem suporte ao desenvolvimento das potencialidades empreendedoras de seus associados. Este trabalho analisa a contribuição desse processo para o desenvolvimento das empresas nos diferentes estágios de incubação. O método de pesquisa foi o estudo de casos múltiplos, com o gerente do CIETEC e quatro empresas em estágios distintos de incubação. A análise dos dados seguiu as técnicas de agrupamento e de cluster. Os principais resultados indicam que: a as capacidades possuem suas raízes em experiências profissionais ou acadêmicas dos empreendedores; b o papel da incubadora na formação dessas capacidades é passivo; c a capacitação de empreendedores para a elaboração de um plano de negócios é um fator positivo para o estabelecimento do negócio; d o networking proporcionado pela incubadora mostrou-se fundamental para todas as empresas; e a infraestrutura é importante para os estágios inicias de incubação, porém perde importância na medida em que as empresas avançam em seus estágios de incubação.

  18. INDICADORES DE CAPACIDAD APLICADOS A LA DESERCIÓN EN LAS UNIVERSIDADES COLOMBIANAS

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    José Daniel Mosquera Artamónov

    2011-01-01

    Full Text Available En este trabajo, se presenta una propuesta para implementar los Índices de Capacidad de un Proceso como herramienta para medir la efectividad de un proceso social. Estos índices son ampliamente empleados en la industria de productos de consumo, pero no es clara la forma como pueden ser usados en el control de procesos sociales. El trabajo se centra en el análisis de aquellos procesos que no están normalmente distribuidos y que por lo tanto, en una primera aproximación teórica, no son susceptibles de ser controlados con el uso de Índices de Capacidad. Mediante un doble ejemplo aplicado al caso de la deserción en las universidades colombianas, se ofrece una metodología detallada de cómo solucionar el problema de la no normalidad de los datos con el uso de la transformación de Box-Cox, la distribución de Weibull y el método de percentiles de Clements. De esta manera, se demuestra la aplicabilidad de los métodos ya contrastados en otros ámbitos, a casos concretos de deserción en las universidades colombianas. El método de índices de capacidad puede usarse para evaluar el proceso de deserción y definir las metas reales de deserción, posibles de cumplir. Se propone además, que esta metodología sea usada en el control de otros procesos sociales.

  19. Capacidad de carga estática en rodamientos. Normalización y tendencias.

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    A. García Toll

    2007-01-01

    Full Text Available Para ilustrar la funcionalidad de la norma NC-ISO 76: 2006, establecida a partir de una adopción idéntica de la Norma ISO 76: 1987/ amd.1: 1999 (E “Cojinetes de Rodamiento – Capacidad de Carga Estática”, son mostradas las correspondencias entre las magnitudes de capacidad de carga estática declaradas en los catálogos técnicos de reconocidos fabricantes de rodamientos con los valores presentes en NC-ISO 76 y considerando diferentes geometrías de rodamientos radiales de bolas rígidos y de contacto angular, rodamientos axiales de bolas y rodamientos de rodillos cilíndricos. Adicionalmente, el estudio ha permitido establecer las dependencias entre la capacidad de carga nominal estática del rodamiento y algunos parámetros geométricos, como el diámetro del elemento rodante, el diámetro interior y la relación diámetro interior - diámetro exterior del cojinete.At the present time, Standard NC-ISO 76: 2006 is a national standard established as identical adoption of ISO standard 76:1987 / amd.1: 1999 (E "Rolling Bearings - Static Load Rating¨. In this sense, the static load rating of rolling bearings declared in technical catalogs of renowned bearing manufacturers and the basic static load rating according to calculation procedures stated in Standard NC-ISO 76 are compared. The evaluation has taken into account different geometries of radial groove ball bearings, angular contact ball bearings, thrust ball bearings and radial roller bearings. Additionally, they are established dependences between the static load rating of rolling bearings and the interior diameter of different types of radial and thrust bearings.

  20. Myocardial contractility in the echo lab: molecular, cellular and pathophysiological basis

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    Bombardini Tonino

    2005-09-01

    Full Text Available Abstract In the standard accepted concept, contractility is the intrinsic ability of heart muscle to generate force and to shorten, independently of changes in the preload or afterload with fixed heart rates. At molecular level the crux of the contractile process lies in the changing concentrations of Ca2+ ions in the myocardial cytosol. Ca2+ ions enter through the calcium channel that opens in response to the wave of depolarization that travels along the sarcolemma. These Ca2+ ions "trigger" the release of more calcium from the sarcoplasmic reticulum (SR and thereby initiate a contraction-relaxation cycle. In the past, several attempts were made to transfer the pure physiological concept of contractility, expressed in the isolated myocardial fiber by the maximal velocity of contraction of unloaded muscle fiber (Vmax, to the in vivo beating heart. Suga and Sagawa achieved this aim by measuring pressure/volume loops in the intact heart: during a positive inotropic intervention, the pressure volume loop reflects a smaller end-systolic volume and a higher end-systolic pressure, so that the slope of the pressure volume relationship moves upward and to the left. The pressure volume relationship is the most reliable index for assessing myocardial contractility in the intact circulation and is almost insensitive to changes in preload and after load. This is widely used in animal studies and occasionally clinically. The limit of the pressure volume relationship is that it fails to take into account the frequency-dependent regulation of contractility: the frequency-dependent control of transmembrane Ca2+ entry via voltage-gated Ca2+ channels provides cardiac cells with a highly sophisticated short-term system for the regulation of intracellular Ca2+ homeostasis. An increased stimulation rate increases the force of contraction: the explanation is repetitive Ca2+ entry with each depolarization and, hence, an accumulation of cytosolic calcium. As the heart

  1. O Risco na Sociedade de Consumo: Superendividamento como Perda de Capacidades

    OpenAIRE

    Carqui, Vagner Bruno Caparelli

    2015-01-01

    Este artículo tiene como objetivo analizar, críticamente, los riesgos que existen en la sociedad de consumo, vinculándolo a la idea de la modernidad líquida, desarrollada por Zygmunt Bauman, considerando el sobreendeudamiento del consumidor entendido en este trabajo como la pérdida de capacidades civiles de los individuos. Las "necesidades" que surgen en la modernidad líquida están relacionados con el consumismo desechable, responsable, entre otras situaciones,por la redefinición del sentido ...

  2. La bioluminiscencia como recurso para potenciar la capacidad creativa del ser humano

    OpenAIRE

    Laugerud Tabarini, Isabel

    2014-01-01

    La bioluminiscencia, capacidad que poseen algunos organismos vivos de producir luz, ocurre mayormente en hábitats marinos donde raramente tiene testigos humanos. Al asombro natural que nos causa lo desconocido se le suma la particularidad de este fenómeno, poco representado y que además nos es solamente evidente en total ausencia de luz. Fuera de su zona de confort es donde el ser humano generalmente incrementa su habilidad de generar y/o conectar ideas para crear algo e implementarlo en su r...

  3. Consideraciones para el desarrollo de capacidades de investigación en universidades privadas

    OpenAIRE

    Maria Luisa Isla; Juan Carlos Seijo; Francisco Javier Espinosa

    2013-01-01

    Se presentan reflexiones y estrategias que contribuyan a formar capacidades de investigación en universidades privadas con investigadores jóvenes comprometidos con el avance del conocimiento en su área de investigación así como con su entorno natural y soc ial. Mediante una combinación de formación en el aula y formación experiencial, se presentan las habilidades investigativas a desarrollar y los ejes de formación universitaria que contribuyen a formar investigadores. Adicionalmente a esta f...

  4. Capacidade de alcance em idosas submetidas a um treinamento de flexibilidade

    Directory of Open Access Journals (Sweden)

    Elciana de Paiva Lima Vieira

    2015-12-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2015v17n6p722   O objetivo do presente estudo foi analisar a influência de um treinamento de flexibilidade nos níveis de amplitude articular máxima e capacidade de alcance em idosas praticantes de hidroginástica participantes do projeto Prev-Quedas. As idosas foram alocadas em dois grupos: Intervenção (GI, n=25, no qual foram submetidas a um programa de treinamento de flexibilidade; e Controle (GC, n=21, no qual as idosas participavam, apenas, das aulas de hidroginástica. O treinamento de flexibilidade teve a duração de três meses e frequência semanal de dois dias, composto por exercícios de alongamento envolvendo tronco e membros inferiores, realizados após as aulas de hidroginástica. O método de alongamento utilizado foi o estático passivo. A aferição foi constituída pelos testes de alcance funcional, lateral e goniométrico. A análise estatística foi feita através dos seguintes testes: normalidade de Shapiro-Wilk, ANCOVA, correlação de Pearson e de Spearman. Foram encontrados resultados significativos para o GI no ganho de amplitude articular máxima na articulação do quadril direito (p=0,0025, porém, o mesmo não foi visto nas demais articulações aferidas, assim como também, não houve melhora na capacidade de alcance funcional e lateral para ambos os grupos. Também não foram vistas correlações significativas entre a capacidade de alcance e amplitude articular no tronco, quadril e tornozelo. Portanto, o treinamento de flexibilidade associado à prática da hidroginástica, promoveu aumento da amplitude articular máxima somente na articulação do quadril, contudo, não foi visto melhora na capacidade de alcance. A prática, somente da hidroginástica, apresentou resultados não significativos.

  5. Análisis de la capacidad de las variables conductuales para pronosticar el rendimiento

    OpenAIRE

    Álvaro Alcalde, Jordi; Gómez López, María Teresa; Barriopedro Moro, Maribel

    2005-01-01

    El objetivo de este estudio fue conocer la capacidad de las variables conductuales propias del fútbol para pronosticar el rendimiento de los equipos en competición. Se analizaron los 380 partidos de la Liga Española de Fútbol de la temporada 2003 – 2004. Se identificaron 31 variables correspondientes a 19 conductas de competición, estableciéndose un total de 80 categorías y se analizaron las relaciones con el rendimiento (goles), en la doble perspectiva según que los equipos actuasen como loc...

  6. Capacidade de Carga Turística: Um Estudo no Caminhos Rurais de Porto Alegre, RS

    Directory of Open Access Journals (Sweden)

    Juliane Magagnin Da Soller

    2013-10-01

    Full Text Available Nesse artigo, apresenta-se o contexto do turismo de base comunitária, além de breve histórico e discussão acerca do conceito e da metodologia da Capacidade de Carga Turística, assim como a adaptação da metodologia para estudo aqui relatado. Descreve-se o estudo realizado para determinar a Capacidade de Carga Turística, tendo por amostra as propriedades rurais partícipes da Associação Porto Alegre Rural (POA RURAL, mais especialmente do roteiro Caminhos Rurais de Porto Alegre, no estado do Rio Grande do Sul. Propôs-se adaptar a para o local a metodologia de cálculo de Capacidade de Carga Turística a partir de Cifuentes (1992; et al 1996, considerando suas particularidades, principalmente aquelas que dizem respeito a saúde e ao bem-estar das famílias que recebem os visitantes e aos impactos ambientais causados pelas construções de infraestrutura turística. A Capacidade de Carga Turística é uma metodologia desenvolvida para áreas preservadas de uso público. Assim, não costuma dar enfoque às questões referentes à comunidade local e aos resíduos gerados pelas instalações e pelos serviços prestados no Turismo.  Tourist Carrying Capacity: A study in the Caminhos Rurais de Porto Alegre, RS  - This paper presents the community based tourism and a brief history, concept and methodology of Tourist Carrying Capacity, and the adaptation of that methodology to the present case. The paper presents the study to determine the Tourist Carrying Capacity in rural proprieties that currently constitute the Porto Alegre Rural Association (RURAL POA, the tourist destination Caminhos Rurais de Porto Alegre, Rio Grande do Sul. The research proposes to adapt the methodology of Tourist Carrying Capacity from Cifuentes (1992, et al 1996, to the Caminhos Rurais, considering its particularities, especially those relate to health and well-being of families who receives visitors, and the environmental impacts caused by the construction of

  7. Testando o Modelo da Casa da Capacidade para o Trabalho entre profissionais do setor hospitalar

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    Maria Carmen Martinez

    Full Text Available RESUMO: Objetivo: Testar o Modelo da Casa da Capacidade para o Trabalho, verificando a hierarquia das dimensões propostas para um grupo de trabalhadores do setor hospitalar. Métodos: Estudo de coorte (2009-2011 conduzido com 599 trabalhadores de um hospital na cidade de São Paulo. Foi usado um formulário com questões sobre dados sociodemográficos, estilo de vida e condições de trabalho, e as versões brasileiras da Escala Estresse no Trabalho, Desequilíbrio Esforço-Recompensa, Work-Related Activities That May Contribute To Job-Related Pain and/or Injury e Índice de Capacidade para o Trabalho (ICT. Foi realizada análise de regressão logística hierárquica: as variáveis independentes foram alocadas em níveis de acordo com as dimensões do modelo teórico para avaliar os fatores associados ao comprometimento da capacidade para o trabalho (CT. Resultados: As variáveis associadas ao comprometimento da CT em cada dimensão foram: (a dimensão sociodemográfica: idade < 30 anos (p = 0,20, (b dimensão saúde: história de acidente de trabalho (p = 0,029, (c dimensão competência profissional: baixo nível educacional (p = 0,008, (d dimensão valores: intensificação do excesso de comprometimento (< 0,001, e (e dimensão trabalho: intensificação do desequilíbrio esforço-recompensa (p = 0,009 e das demandas elevadas (p = 0,040. Conclusão: Os resultados do estudo confirmaram as dimensões propostas para o Modelo da Casa da Capacidade para o Trabalho, indicando que ele é válido como representação de um construto multidimensional de determinação multicausal, podendo ser utilizado na gestão da CT.

  8. As capacidades da liderança na perspectiva do diálogo.

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    Francisco Javier Uribe Rivera

    2008-05-01

    unificadora o manejo comunicativo da intersubjetividade, a capacidade de mobilizar e de gerar contextos dialógicos capazes de patrocinar o consenso necessário à gestão por compromissos. Palavras-chave: liderança; gestão comunicativa; diálogo e condução; aprendizagem organizacional. Abstract This paper is a review of the concept of leadership including several authors, having as an unified feature the communicative management of intersubjetivity rapports, the capacity of generate mobilization and dialogical contexts that can allow the consensus needed for a management based on commitments. Keywords: leadership; communicative management; dialogue and management; learning organization.

  9. Fadiga e capacidade para o trabalho em turnos fixos de doze horas

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    Metzner Ricardo Jorge

    2001-01-01

    Full Text Available OBJETIVO: Analisar as variáveis que interferem na percepção de fadiga e na capacidade para o trabalho em trabalhadores que executam suas atividades em turnos fixos diurnos e noturnos. MÉTODOS: Estudo transversal, com participação de 43 trabalhadores de turnos diurnos e noturnos de uma indústria têxtil, que trabalhavam em turnos fixos de 12 horas diárias e semana reduzida. Mediante vários questionários, o grupo estudado respondeu a questões sobre: fadiga, índice de capacidade para o trabalho, características individuais, estilos de vida e condições de trabalho. Foi feita análise de regressão linear univariada. RESULTADOS: Os fatores que influenciaram a percepção de fadiga associam-se a estilos de vida dos trabalhadores (a prática de exercício físico é um fator protetor e à dificuldade em manter o sono, que, se presente, aumenta a percepção de fadiga. Os fatores associados à percepção do índice de capacidade para o trabalho (ICT foram o tempo de exercício na função e o turno noturno de trabalho: quanto maior o primeiro, menor o ICT; trabalhar à noite aumenta o ICT. A duração da jornada diária de 12 horas pode provocar aumento considerável na carga de trabalho, influenciando a percepção do trabalhador sobre a capacidade para o trabalho, a fadiga e as alterações do sono. CONCLUSÕES: Os resultados indicam que nem sempre o trabalho noturno mostra-se como fator prejudicial à saúde. Entretanto, a amostra estudada é pequena, o estudo é transversal, e pode ter ocorrido um efeito de seleção. Assim, é necessária a realização de estudos longitudinais, com amostras maiores, dado que o ICT tende a diminuir à medida que aumenta o tempo na função.

  10. Las Capacidades Dinámicas e Administración Estratégica

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    Vidigal Fernandes Martins

    2011-09-01

    Full Text Available Este ensayo teórico se centra en las teorías que explican cómo las organizaciones a obtener y mantener una ventaja competitiva. Tres Paradigmas se resumen, el paradigma y el paradigma de conflicto estratégico de Porter, y las conversaciones para poner fin al paradigma de recursos basado en recursos. "Capacidad dinámica" se derivan de la fuerte relación entre las nociones generalizadas de eficacia con respecto a los cambios y las fórmulas genéricas e la ventaja competitiva sustentable.

  11. Capacidad de agencia de autocuidado y factores de riesgo cardiovascular en adolescentes

    OpenAIRE

    Morales Aguilar, Rosa del Socorro

    2013-01-01

    Este estudio tuvo como objetivo determinar la relación entre la capacidad de agencia de autocuidado y los factores de riesgo cardiovascular en adolescentes de una Institución de Educación Superior en el Distrito de Barranquilla. Metodología: Estudio descriptivo, exploratorio, de corte transversal, con abordaje cuantitativo, basado en la teoría del déficit de autocuidado de Orem. La muestra fue de 133 adolescentes, seleccionados mediante muestreo aleatorio simple. Se aplicó la escala ASA, el c...

  12. Melodías en el proceso de desarrollo de la capacidad lectora

    OpenAIRE

    Fonseca Mora, María Carmen

    2013-01-01

    La existencia de un vínculo entre la destreza lectora, la capacidad auditiva y la música ha sido descrita en numerosos estudios. Leer un texto significa sonorizar un mensaje escrito, ya que sin sonidos, en la lectura silenciosa es la voz interior del lector, no puede haber acceso desde los símbolos escritos al léxico y a la comprensión del mismo. Tanto en la lectura en voz alta como en la lectura silenciosa, las grafías que descifra el ojo necesitan apoyarse en elementos son...

  13. Capacidad administrativa como factor de eficiencia interna y global de las organizaciones

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    Carlos E. Martínez Fajardo

    1997-06-01

    Full Text Available El concepto de eficiencia ha sido precisado y simplificado por los autores de la teoría clásica de la administración en el sentido de maximizar la producción de las organizaciones con los mínimos costos. En el presente artículo se analizará la eficiencia interna y global de las organizaciones de acuerdo con nuevos criterios adicionales que permitan estudiar el problema con un enfoque de mayor complejidad la naturaleza, fines y estructura de las organizaciones, entre ellos la incidencia del factor de este siglo denominado capacidad administrativa.

  14. Aspiração manual intrauterina no tratamento do abortamento incompleto até 12 semanas gestacionais: uma alternativa à curetagem uterina Manual vacuum aspiration uterine treatment of incomplete abortion to 12 gestational weeks: an alternative to curettage

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    Marcio Pedroso Saciloto

    2011-10-01

    Full Text Available OBJETIVO: Analisar a eficácia e a ocorrência de complicações, além do tempo de permanência hospitalar e as perdas sanguíneas. MÉTODOS: Trinta pacientes foram selecionadas, alternada e consecutivamente, em um dos grupos (15 no Grupo Curetagem e 15 no Grupo de Aspiração manual intrauterina. As variáveis analisadas foram: eficácia do método, ocorrência de complicações, tempo pré-procedimento, tempo de execução do procedimento, tempo pós-procedimento e tempo total de permanência hospitalar, além de hematócrito e hemoglobina, medidas antes e após o procedimento. As pacientes foram avaliadas clinicamente 10 a 14 dias após o procedimento. Para a análise estatística, foram aplicados testes paramétricos e não-paramétricos e o nível de significância admitido foi de p>0,05. RESULTADOS: Ambos os métodos foram eficazes e não foi registrada nenhuma complicação. As perdas sanguíneas foram semelhantes e o tempo de permanência hospitalar foi significativamente menor no Grupo de Aspiração Manual Intrauterina (p=0,03. CONCLUSÃO: a aspiração manual intrauterina é tão eficaz e segura quanto à curetagem uterina, com a vantagem de necessitar menor tempo de permanência hospitalar, o que aumenta a resolutividade do método, melhorando a qualidade da assistência a essas pacientes.PURPOSE: To analyze the effectiveness and occurrence of complications, in addition to hospitalization time and blood losses. METHODS: Thirty patients were assigned alternatively and consecutively to one of two groups (15 to the Curettage Group and 15 to the Manual Vacuum Aspiration Group. The following variables were analyzed: effectiveness of the method, occurrence of complications, time before the procedure, time of execution of the procedure, time after the procedure, and total time of hospital permanence, in addition to hematocrit and hemoglobin, which were measured before and after the procedure. Patients were evaluated clinically 10 to 14

  15. Transfusão intra-uterina em fetos afetados pela doença hemolítica perinatal grave: um estudo descritivo Intrauterine transfusion in fetuses affected by severe perinatal hemolytic disease: a descriptive study

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    Dorival Antônio Vitorello

    1998-04-01

    Full Text Available Objetivo: analisar 54 transfusões intravasculares intra-uterinas (TIVs, ressaltando complicações do procedimento e morbimortalidade perinatal. Material e Métodos: fetos submetidos a TIVs na Clínica Materno-Fetal e Maternidade Carmela Dutra (Florianópolis, SC, entre janeiro de 1992 e agosto de 1997, foram incluídos no estudo. As características das gestantes, dados relativos ao procedimento e ao recém-nascido foram tabulados para análise e apresentados de forma descritiva, utilizando-se percentagem, média, desvio padrão, mediana, variação e risco relativo (RR com intervalo de confiança de 95% (IC conforme apropriado. Resultados: foram realizadas 50 TIVs e quatro ex-sangüíneo transfusões em 21 fetos. Houve quatro óbitos (20%, três dos quais (75% ocorridos em fetos hidrópicos. A idade gestacional média quando da primeira transfusão foi de 29,1 semanas. A concentração média de hemoglobina foi de 5,69 mg/dl. A taxa de mortalidade decorrente do procedimento foi de 7,4%. A idade gestacional média ao nascimento foi 33,9 semanas e o peso médio foi 2.437 gramas. Sessenta e cinco por cento dos recém-nascidos receberam ex-sangüíneo transfusão complementar. Conclusão: a taxa de mortalidade por procedimento (7,4% foi semelhante à relatada na literatura mundial. A taxa de mortalidade perinatal (20% foi mais elevada do que a relatada na literatura estrangeira, mas inferior à relatada em estudo conduzido no Brasil, no qual a prevalência de fetos hidrópicos foi semelhante.Objective: to report 54 intrauterine intravascular transfusions (IITs, describing procedure related complications and associated perinatal morbidity and mortality. Methods: fetuses undergoing IITs at Clínica Materno-Fetal and Maternidade Carmela Dutra, Florianópolis, SC, between January 1992 and August 1997 were included in the study. Patients demographics, procedure and newborn related data were tabulated for analysis and presented in descriptive form

  16. Uso do misoprostol em substituição à curetagem uterina em gestações interrompidas precocemente Misoprostol in substitution at uterine curettage in early pregnancy failure

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    Francisco Carlos Nogueira Arcanjo

    2011-06-01

    Full Text Available OBJETIVOS: Avaliar a eficácia do misoprostol administrado via vaginal para esvaziamento uterino em gestações interrompidas precocemente, bem como o tempo entre a administração e o esvaziamento, correlacionando-os com a idade gestacional. MÉTODOS: Ensaio clínico com 41 pacientes com gestações interrompidas entre a 7ª e a 12ª semanas gestacionais, com média de idade de 27,3 (±6,1 anos. A paridade média foi de 2,2 (±1,2 partos; o número médio de abortamentos prévios foi 0,2 (±0,5. Foram administrados 800 µg de misoprostol via vaginal, em dose única; após 24 horas, foi realizado ultrassom transvaginal. Considerou-se abortamento completo quando o diâmetro anteroposterior da cavidade endometrial media 8 semanas de idade gestacional em relação aos desfechos: frequência de abortamento completo e intervalo entre administração de misoprostol e o abortamento (em minutos. O nível de significância utilizado foi de 5%. RESULTADOS: A idade gestacional, no momento do diagnóstico, foi de 8,5 semanas em média (DP=1,5. Os intervalos entre a administração de misoprostol e as contrações uterinas, e entre a administração e o abortamento, foram de 322,5±97,0 min e 772,5±201,0 min, respectivamente. Houve abortamento completo em 80,3%. No primeiro grupo, a taxa de sucesso foi de 96,2% e no segundo, de 53,3% (pPURPOSE: To evaluate the effectiveness of misoprostol administered vaginally for uterine evacuation in interrupted early pregnancies and the time between the administration and emptying correlated with gestational age. METHODS: Clinical trial with 41 patients with pregnancies interrupted between the 7th and the 12th gestational weeks. The mean age was 27.3 (±6.1 years. Mean parity was 2.2 (±1.2 deliveries. The average number of previous abortions was 0.2 (± 0.5. Misoprostol was administered vaginally in a single 800 µg dose and transvaginal ultrasound was performed after 24 hours. Abortion was considered complete when the

  17. Evaluación de capacidades para testificar en víctimas con discapacidad intelectual

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    María José Contreras

    2015-01-01

    Full Text Available Las habilidades para testificar de las víctimas con discapacidad intelectual (DI suelen ser consideradas de acuerdo con estereotipos más que con su realidad, teniendo en cuenta que se observa una gran heterogeneidad en este colectivo. Por ello es necesario un procedimiento que permita conocer específicamente las características cognitivas de cada víctima con DI con el fin último de adaptar los procedimientos policiales y judiciales a sus capacidades y evaluar adecuadamente la información que aportan en sus testimonios. Con este objetivo se desarrolló el protocolo de entrevista CAPALIST, que evalúa las capacidades cognitivas que intervendrían en la aportación de testimonio. En el presente trabajo se describe la herramienta y se aportan datos sobre su aplicación a cuatro víctimas reales de abuso sexual con DI. Los resultados muestran mínimas diferencias en los acuerdos interjueces. Se concluye que el CAPALIST podría ser de utilidad en la evaluación de las habilidades para testificar en víctimas con DI.

  18. El enfoque de las capacidades, la agencia cognitiva y los recursos morales

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    Agustín Reyes Morela

    2012-02-01

    Full Text Available El enfoque de Sen se presenta como una alternativa en el terreno de la justicia distributiva. Su noción central es la de capacidad de agencia, es decir, la libertad efectiva para alcanzar aquello que se tienen razones para valorar. A su vez, la idea de agencia cognitiva refiere a la capacidad de revisar o reforzar estas razones. Bajo la autocomprensión de las sociedades modernas, la única forma válida de desarrollarla es a través de la deliberación pública. Del intercambio surgen los recursos morales (entre ellos las razones morales que permiten modificar la concepción del bien y fortalecer sentido de justicia de los sujetos.The Sen’s approach is presented as an alternative in the field of distributive justice. Its main concept is the capability of agency, namely the effective freedom to achieve whatever you have reason to value. In turn, the idea of cognitive agency refers to the capability to review and strengthen these reasons. Under the self-understanding of modern societies, the only valid way to develop them is through public deliberation. Through the exchange emerge the moral resources that allow to modify the conception of the good and strengthen the sense of justice of the people.

  19. EFECTIVIDAD DE LA ORIENTACIÓN EMPRENDEDORA: EL PAPEL DEL CAPITAL SOCIAL Y LAS CAPACIDADES

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    Rodrigo-Alarcón, Job

    2014-09-01

    Full Text Available La orientación emprendedora ha sido uno de los aspectos que mayor interés ha suscitado en los últimos años en el campo del entrepreneurship. La revisión de la literatura nos permite señalar la necesidad de abordar la ambigüedad y la complejidad de la relación entre la orientación emprendedora y los resultados empresariales. En este trabajo planteamos esta relación desde un enfoque configuracional, abordando la coherencia de factores relacionales —capital social— y organizativos —capacidades tecnológicas y de marketing— con la orientación emprendedora. El objetivo del trabajo consiste en desarrollar un modelo configuracional que explique el efecto moderador conjunto del capital social y las capacidades empresariales sobre la efectividad de la orientación emprendedora. Se establecen 3 modelos teóricos —universal, contingente y configuracional— que se definen mediante proposiciones teóricas. Exploramos y ejemplificamos empíricamente las relaciones establecidas mediante un estudio de casos de empresas agroalimentarias españolas. Finalmente, extraemos diversas conclusiones a partir de los modelos planteados y proponemos futuras líneas de investigación.

  20. The Functional Lumen Imaging Probe Detects Esophageal Contractility Not Observed With Manometry in Patients With Achalasia.

    Science.gov (United States)

    Carlson, Dustin A; Lin, Zhiyue; Kahrilas, Peter J; Sternbach, Joel; Donnan, Erica N; Friesen, Laurel; Listernick, Zoe; Mogni, Benjamin; Pandolfino, John E

    2015-12-01

    The functional lumen imaging probe (FLIP) could improve the characterization of achalasia subtypes by detecting nonocclusive esophageal contractions not observed with standard manometry. We aimed to evaluate esophageal contractions during volumetric distention in patients with achalasia using FLIP topography. Fifty-one treatment-naive patients with achalasia, defined and subclassified by high-resolution esophageal pressure topography, and 10 asymptomatic individuals (controls) were evaluated with the FLIP during endoscopy. During stepwise distension, simultaneous intrabag pressures and 16 channels of cross-sectional areas were measured; data were exported to software that generated FLIP topography plots. Esophageal contractility was identified by noting periods of reduced luminal diameter. Esophageal contractions were characterized further by propagation direction, repetitiveness, and based on whether they were occluding or nonoccluding. Esophageal contractility was detected in all 10 controls: 8 of 10 had repetitive antegrade contractions and 9 of 10 had occluding contractions. Contractility was detected in 27% (4 of 15) of patients with type I achalasia and in 65% (18 of 26, including 9 with occluding contractions) of patients with type II achalasia. Contractility was detected in all 10 patients with type III achalasia; 8 of these patients had a pattern of contractility that was not observed in controls (repetitive retrograde contractions). Esophageal contractility not observed with manometry can be detected in patients with achalasia using FLIP topography. The presence and patterns of contractility detected with FLIP topography may represent variations in pathophysiology, such as mechanisms of panesophageal pressurization in patients with type II achalasia. These findings could have implications for additional subclassification to supplement prediction of the achalasia disease course. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights

  1. Menor de edad y capacidad de ejercicio: Reto del Derecho Familiar contemporáneo Menor de edad y capacidad de ejercicio: Reto del Derecho Familiar contemporáneo.

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    Jetzabel Mireya Montejo Rivero

    2012-04-01

    Full Text Available Change in family relations that took place at the opening of the 21st comporting new paradigms in conceptions of minor is already in progress. These reflections are referred to understanding child legal status capacity that takes into consideration its legal ability from the perspective of dynamic participation in concrete legal relations according to his progressive ability and secures the protection of his rights at the same time. The present article demonstrate the legal concepts of individual, personality and ability are interpreted the legal ability of child individuals is evaluated following that viewpoint. The study outlines the necessity of harmonizing the notion of child and ability for “child’s best interest” in contemporary family low.Los cambios en las relaciones familiares acaecidos en los albores de siglo XXI, comportan nuevos paradigmas en la concepción de la capacidad del menor. En estas reflexiones, se hace referencia a la enunciación de la capacidad de obrar del menor desde una dinámica participativa en las relaciones jurídicas civiles y familiares acorde a su capacidad progresiva y una más efectiva protección al ejercicio de sus derechos. El presente artículo, expone sucintamente valoraciones sobre el ejercicio de la capacidad del menor a partir de la fundamentación teórica de los conceptos jurídicos de persona, personalidad y capacidad, en aras de armonizar las nociones de menor de edad y capacidad de ejercicio desde el interés superior del niño en el Derecho Familiar contemporáneo.

  2. Isolation and maintenance-free culture of contractile myotubes from Manduca sexta embryos.

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    Amanda L Baryshyan

    Full Text Available Skeletal muscle tissue engineering has the potential to treat tissue loss and degenerative diseases. However, these systems are also applicable for a variety of devices where actuation is needed, such as microelectromechanical systems (MEMS and robotics. Most current efforts to generate muscle bioactuators are focused on using mammalian cells, which require exacting conditions for survival and function. In contrast, invertebrate cells are more environmentally robust, metabolically adaptable and relatively autonomous. Our hypothesis is that the use of invertebrate muscle cells will obviate many of the limitations encountered when mammalian cells are used for bioactuation. We focus on the tobacco hornworm, Manduca sexta, due to its easy availability, large size and well-characterized muscle contractile properties. Using isolated embryonic cells, we have developed culture conditions to grow and characterize contractile M. sexta muscles. The insect hormone 20-hydroxyecdysone was used to induce differentiation in the system, resulting in cells that stained positive for myosin, contract spontaneously for the duration of the culture, and do not require media changes over periods of more than a month. These cells proliferate under normal conditions, but the application of juvenile hormone induced further proliferation and inhibited differentiation. Cellular metabolism under normal and low glucose conditions was compared for C2C12 mouse and M. sexta myoblast cells. While differentiated C2C12 cells consumed glucose and produced lactate over one week as expected, M. sexta muscle did not consume significant glucose, and lactate production exceeded mammalian muscle production on a per cell basis. Contractile properties were evaluated using index of movement analysis, which demonstrated the potential of these cells to perform mechanical work. The ability of cultured M. sexta muscle to continuously function at ambient conditions without medium replenishment

  3. Changes in muscle fiber contractility and extracellular matrix production during skeletal muscle hypertrophy.

    Science.gov (United States)

    Mendias, Christopher L; Schwartz, Andrew J; Grekin, Jeremy A; Gumucio, Jonathan P; Sugg, Kristoffer B

    2017-03-01

    Skeletal muscle can adapt to increased mechanical loads by undergoing hypertrophy. Transient reductions in whole muscle force production have been reported during the onset of hypertrophy, but contractile changes in individual muscle fibers have not been previously studied. Additionally, the extracellular matrix (ECM) stores and transmits forces from muscle fibers to tendons and bones, and determining how the ECM changes during hypertrophy is important in understanding the adaptation of muscle tissue to mechanical loading. Using the synergist ablation model, we sought to measure changes in muscle fiber contractility, collagen content, and cross-linking, and in the expression of several genes and activation of signaling proteins that regulate critical components of myogenesis and ECM synthesis and remodeling during muscle hypertrophy. Tissues were harvested 3, 7, and 28 days after induction of hypertrophy, and nonoverloaded rats served as controls. Muscle fiber specific force (sF o ), which is the maximum isometric force normalized to cross-sectional area, was reduced 3 and 7 days after the onset of mechanical overload, but returned to control levels by 28 days. Collagen abundance displayed a similar pattern of change. Nearly a quarter of the transcriptome changed over the course of overload, as well as the activation of signaling pathways related to hypertrophy and atrophy. Overall, this study provides insight into fundamental mechanisms of muscle and ECM growth, and indicates that although muscle fibers appear to have completed remodeling and regeneration 1 mo after synergist ablation, the ECM continues to be actively remodeling at this time point. NEW & NOTEWORTHY This study utilized a rat synergist ablation model to integrate changes in single muscle fiber contractility, extracellular matrix composition, activation of important signaling pathways in muscle adaption, and corresponding changes in the muscle transcriptome to provide novel insight into the basic

  4. The effect of exercise hypertrophy and disuse atrophy on muscle contractile properties: a mechanomyographic analysis.

    Science.gov (United States)

    Than, Christian; Tosovic, Danijel; Seidl, Laura; Mark Brown, J

    2016-12-01

    To determine whether mechanomyographic (MMG) determined contractile properties of the biceps brachii change during exercise-induced hypertrophy and subsequent disuse atrophy. Healthy subjects (mean ± SD, 23.7 ± 2.6 years, BMI 21.8 ± 2.4, n = 19) performed unilateral biceps curls (9 sets × 12 repetitions, 5 sessions per week) for 8 weeks (hypertrophic phase) before ceasing exercise (atrophic phase) for the following 8 weeks (non-dominant limb; treatment, dominant limb; control). MMG measures of muscle contractile properties (contraction time; T c , maximum displacement; D max , contraction velocity; V c ), electromyographic (EMG) measures of muscle fatigue (median power frequency; MPF), strength measures (maximum voluntary contraction; MVC) and measures of muscle thickness (ultrasound) were obtained. Two-way repeated measures ANOVA showed significant differences (P muscle thickness was greater than control, reflecting gross hypertrophy. MMG variables Dmax (weeks 2, 7) and Vc (weeks 7, 8) declined. During the atrophic phase, MVC (weeks 9-12) and muscle thickness (weeks 9, 10) initially remained high before declining to control levels, reflecting gross atrophy. MMG variables D max (weeks 9, 14) and V c (weeks 9, 14, 15) also declined during the atrophic phase. No change in T c was found throughout the hypertrophic or atrophic phases. MMG detects changes in contractile properties during stages of exercise-induced hypertrophy and disuse atrophy suggesting its applicability as a clinical tool in musculoskeletal rehabilitation.

  5. Myocardial mitochondrial and contractile function are preserved in mice lacking adiponectin.

    Directory of Open Access Journals (Sweden)

    Martin Braun

    Full Text Available Adiponectin deficiency leads to increased myocardial infarct size following ischemia reperfusion and to exaggerated cardiac hypertrophy following pressure overload, entities that are causally linked to mitochondrial dysfunction. In skeletal muscle, lack of adiponectin results in impaired mitochondrial function. Thus, it was our objective to investigate whether adiponectin deficiency impairs mitochondrial energetics in the heart. At 8 weeks of age, heart weight-to-body weight ratios were not different between adiponectin knockout (ADQ-/- mice and wildtypes (WT. In isolated working hearts, cardiac output, aortic developed pressure and cardiac power were preserved in ADQ-/- mice. Rates of fatty acid oxidation, glucose oxidation and glycolysis were unchanged between groups. While myocardial oxygen consumption was slightly reduced (-24% in ADQ-/- mice in isolated working hearts, rates of maximal ADP-stimulated mitochondrial oxygen consumption and ATP synthesis in saponin-permeabilized cardiac fibers were preserved in ADQ-/- mice with glutamate, pyruvate or palmitoyl-carnitine as a substrate. In addition, enzymatic activity of respiratory complexes I and II was unchanged between groups. Phosphorylation of AMP-activated protein kinase and SIRT1 activity were not decreased, expression and acetylation of PGC-1α were unchanged, and mitochondrial content of OXPHOS subunits was not decreased in ADQ-/- mice. Finally, increasing energy demands due to prolonged subcutaneous infusion of isoproterenol did not differentially affect cardiac contractility or mitochondrial function in ADQ-/- mice compared to WT. Thus, mitochondrial and contractile function are preserved in hearts of mice lacking adiponectin, suggesting that adiponectin may be expendable in the regulation of mitochondrial energetics and contractile function in the heart under non-pathological conditions.

  6. Separate effects of ischemia, hypoxia, and contractility on thallium-201 kinetics in rabbit myocardium

    International Nuclear Information System (INIS)

    Leppo, J.A.; Macneil, P.B.; Moring, A.F.; Apstein, C.S.

    1986-01-01

    The effects of hypoxia and ischemia, as well as altered contractility, on thallium-201 ( 201 TI) kinetics were evaluated in 42 isolated isovolumetrically contracting rabbit hearts. In Group A, three subgroups (n = 7 each) were studied that had either normal flow and oxygenation, hypoxia and normal flow, or ischemic flow and normal perfusate oxygen content. In Group B, three subgroups (n = 7 each) were studied and all hearts had normal flow but the contractile state was either enhanced with isoproterenol or impaired by hypocalcemia. A hemoglobin-free buffer perfusate was used in all experiments and multiple timed collections of arterial and coronary sinus effluent were used to model myocardial isotope activity during 30 min of constant uptake followed by 30 min of tracer clearance. During ischemia, hypoxia and hypocalcemia peak developed pressure and peak positive and negative dP/dt were all significantly reduced when compared to normal hemodynamic parameters (p less than 0.01). As expected, isoproterenol significantly elevated these parameters (p less than 0.04). Myocardial 201 TI kinetics were adequately described utilizing a bi-exponential model having a fast and slow component. Only ischemic hearts had significantly lower rate constants for 201 TI uptake and clearance than normal hearts (p less than 0.001). The mean (+/- s.d.) myocardial uptake and clearance rates for 201 TI (%/min) varied between 4.86 +/- 0.87 and 7.18 +/- 1.45 for the remaining groups of hearts. Therefore, myocardial 201 TI kinetics appear to be dominated by coronary flow and may not reflect marked alterations in the metabolic and contractile state. These data suggest that normal 201 TI uptake in impaired or hypercontractile cells, receiving normal flow, may not represent normal cellular function

  7. Opportunities to Target Specific Contractile Abnormalities with Smooth Muscle Protein Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Annegret Ulke-Lemée

    2010-05-01

    Full Text Available Smooth muscle is a major component of most hollow organ systems (e.g., airways, vasculature, bladder and gut/gastrointestine; therefore, the coordinated regulation of contraction is a key property of smooth muscle. When smooth muscle functions normally, it contributes to general health and wellness, but its dysfunction is associated with morbidity and mortality. Rho-associated protein kinase (ROCK is central to calcium-independent, actomyosin-mediated contractile force generation in the vasculature, thereby playing a role in smooth muscle contraction, cell motility and adhesion. Recent evidence supports an important role for ROCK in the increased vasoconstriction and remodeling observed in various models of hypertension. This review will provide a commentary on the development of specific ROCK inhibitors and their clinical application. Fasudil will be discussed as an example of bench-to-bedside development of a clinical therapeutic that is used to treat conditions of vascular hypercontractility. Due to the wide spectrum of biological processes regulated by ROCK, many additional clinical indications might also benefit from ROCK inhibition. Apart from the importance of ROCK in smooth muscle contraction, a variety of other protein kinases are known to play similar roles in regulating contractile force. The zipper-interacting protein kinase (ZIPK and integrin-linked kinase (ILK are two well-described regulators of contraction. The relative contribution of each kinase to contraction depends on the muscle bed as well as hormonal and neuronal stimulation. Unfortunately, specific inhibitors for ZIPK and ILK are still in the development phase, but the success of fasudil suggests that inhibitors for these other kinases may also have valuable clinical applications. Notably, the directed inhibition of ZIPK with a pseudosubstrate molecule shows unexpected effects on the contractility of gastrointestinal smooth muscle.

  8. The role of apical contractility in determining cell morphology in multilayered epithelial sheets and tubes

    Science.gov (United States)

    Zhen Tan, Rui; Lai, Tanny; Chiam, K.-H.

    2017-08-01

    A multilayered epithelium is made up of individual cells that are stratified in an orderly fashion, layer by layer. In such tissues, individual cells can adopt a wide range of shapes ranging from columnar to squamous. From histological images, we observe that, in flat epithelia such as the skin, the cells in the top layer are squamous while those in the middle and bottom layers are columnar, whereas in tubular epithelia, the cells in all layers are columnar. We develop a computational model to understand how individual cell shape is governed by the mechanical forces within multilayered flat and curved epithelia. We derive the energy function for an epithelial sheet of cells considering intercellular adhesive and intracellular contractile forces. We determine computationally the cell morphologies that minimize the energy function for a wide range of cellular parameters. Depending on the dominant adhesive and contractile forces, we find four dominant cell morphologies for the multilayered-layered flat sheet and three dominant cell morphologies for the two-layered curved sheet. We study the transitions between the dominant cell morphologies for the two-layered flat sheet and find both continuous and discontinuous transitions and also the presence of multistable states. Matching our computational results with histological images, we conclude that apical contractile forces from the actomyosin belt in the epithelial cells is the dominant force determining cell shape in multilayered epithelia. Our computational model can guide tissue engineers in designing artificial multilayered epithelia, in terms of figuring out the cellular parameters needed to achieve realistic epithelial morphologies.

  9. Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

    Directory of Open Access Journals (Sweden)

    F.A. Capeto

    2015-05-01

    Full Text Available Esophageal atresia (EA is characterized by esophageal and gastric motility changes secondary to developmental and postsurgical damage. This study evaluated the in vitro contractile profile of the distal esophagus and gastric fundus in an experimental model of EA induced by doxorubicin (DOXO. Wistar pregnant rats received DOXO 2.2 mg/kg on the 8th and 9th gestational days. On day 21.5, fetuses were collected, sacrificed, and divided into groups: control, DOXO without EA (DOXO-EA, and DOXO with EA (DOXO+EA. Strips from the distal esophagus and gastric fundus were mounted on a wire myograph and isolated organ-bath system, respectively, and subjected to increasing concentrations of carbamylcholine chloride (carbachol, CCh. The isolated esophagus was also stimulated with increasing concentrations of KCl. In esophagus, the concentration-effect curves were reduced in response to CCh in the DOXO+EA and DOXO-EA groups compared to the control group (P0.05. In response to KCl, the distal esophagus samples in the three groups were not statistically different with regard to Emax or EC50 values (P>0.05. No significant difference was noted for EC50 or Emax values in fundic strips stimulated with CCh (P>0.05. In conclusion, exposure of dams to DOXO during gestation inhibited the contractile behavior of esophageal strips from offspring in response to CCh but not KCl, regardless of EA induction. The gastric fundus of DOXO-exposed offspring did not have altered contractile responsiveness to cholinergic stimulation.

  10. Contractility-afterload mismatch in patients with protein-losing enteropathy after the Fontan operation.

    Science.gov (United States)

    Ozawa, Hideto; Ueno, Takayoshi; Iwai, Shigemitsu; Kawata, Hiroaki; Nishigaki, Kyouichi; Kishimoto, Hidefumi; Sawa, Yoshiki

    2014-10-01

    This study aimed to clarify the relationship between onset of protein-losing enteropathy (PLE) and Fontan circulation, with special reference to the development of contractility-afterload mismatch. The PLE group comprised 9 patients who experienced PLE after undergoing the Fontan operation, and the control group consisted of 32 patients had did not experienced PLE more than 10 years after the Fontan operation. The study compared the pre- and postoperative values of arterial elastance (Ea), end-systolic elastance (Ees), and contractility-afterload mismatch (Ea/Ees). Furthermore, the variations in the values were examined during the preoperative, postoperative, and midterm postoperative periods in seven PLE patients who underwent cardiac catheterization at the onset of PLE and during the pre- and postintervention periods in three PLE patients who underwent surgical intervention to improve the Fontan circulation after the onset of PLE. Comparison of the values obtained before and after Fontan operations showed that the Ea values increased significantly in the PLE group. However, the pre- and postoperative Ees values did not differ in the two groups. During the postoperative period, Ea/Ees increased significantly, and the Ea and Ea/Ees values increased continuously until the onset of PLE in the PLE group. In the patients who underwent surgical intervention to improve the Fontan circulation after the onset of PLE, the Ea/Ees decreased significantly, and the serum albumin levels improved after the intervention. Contractility-afterload mismatch, mainly caused by the increase in the afterload of the systemic ventricle, may have an important role in the development of PLE after the Fontan operation.

  11. Altered Ca fluxes and contractile state during pH changes in cultured heart cells

    International Nuclear Information System (INIS)

    Kim, D.; Smith, T.W.

    1987-01-01

    The authors studied mechanisms underlying changes in myocardial contractile state produced by intracellular (pH/sub i/) or extracellular (pH 0 ) changes in pH using cultured chick embryo ventricular cells. A change in pH 0 of HEPES-buffered medium from 7.4 to 6.0 or to 8.8 changed the amplitude of cell motion by -85 or +60%, and 45 Ca uptake at 10 s by -29 or +22%, respectively. The pH 0 induced change in Ca uptake was not sensitive to nifedipine but was Na gradient dependent. Changes in pH/sub i/ produced by NH 4 Cl or preincubation in media at pH values ranging from 6.0 to 8.8 failed to alter significantly 45 Ca uptake or efflux. However, larger changes in pH/sub i/ were associated with altered Ca uptake. Changes in pH 0 from 7.5 to 6.0 or to 8.8 were associated with initial changes in 45 Ca efflux by +17 or -18%, respectively, and these effects were not Na dependent. Exposure of cells to 20 mM NH 4 Cl produced intracellular alkalinization and a positive inotropic effect, whereas subsequent removal of NH 4 Cl caused intracellular acidification and a negative inotropic effect. There was, however, a lack of close temporal relationships between pH/sub i/ and contractile state. These results indicated that pH 0 -induced changes in contractile state in cultured heart cells are closely correlated with altered transarcolemmal Ca movements and presumably are due to these Ca flux changes

  12. Acute exposure to lead increases myocardial contractility independent of hypertension development

    International Nuclear Information System (INIS)

    Fioresi, M.; Furieri, L.B.; Simões, M.R.; Ribeiro, R.F. Junior; Meira, E.F.; Fernandes, A.A.; Stefanon, I.; Vassallo, D.V.

    2013-01-01

    We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na + ,K + -ATPase and myosin Ca 2+ -ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na + ,K + -ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension

  13. Facilitated ethanol metabolism promotes cardiomyocyte contractile dysfunction through autophagy in murine hearts.

    Science.gov (United States)

    Guo, Rui; Hu, Nan; Kandadi, Machender R; Ren, Jun

    2012-04-01

    Chronic drinking leads to myocardial contractile dysfunction where ethanol metabolism plays an essential role. Acetaldehyde, the main ethanol metabolite, mediates alcohol-induced cell injury although the underlying mechanism is still elusive. This study was designed to examine the mechanism involved in accelerated ethanol metabolism-induced cardiac defect with a focus on autophagy. Wild-type FVB and cardiac-specific overexpression of alcohol dehydrogenase mice were placed on a 4% nutrition-balanced alcohol diet for 8 weeks. Myocardial histology, immunohistochemistry, autophagy markers and signal molecules were examined. Expression of micro RNA miR-30a, a potential target of Beclin 1, was evaluated by real-time PCR. Chronic alcohol intake led to cardiac acetaldehyde accumulation, hypertrophy and overt autophagosome accumulation (LC3-II and Atg7), the effect of which was accentuated by ADH. Signaling molecules governing autophagy initiation including class III PtdIns3K, phosphorylation of mTOR and p70S6K were enhanced and dampened, respectively, following alcohol intake. These alcohol-induced signaling responses were augmented by ADH. ADH accentuated or unmasked alcohol-induced downregulation of Bcl-2, Bcl-xL and MiR-30a. Interestingly, ADH aggravated alcohol-induced p62 accumulation. Autophagy inhibition using 3-MA abolished alcohol-induced cardiomyocyte contractile anomalies. Moreover, acetaldehyde led to cardiomyocyte contractile dysfunction and autophagy induction, which was ablated by 3-MA. Ethanol or acetaldehyde increased GFP-LC3 puncta in H9c2 cells, the effect of which was ablated by 3-MA but unaffected by lysosomal inhibition using bafilomycin A(1), E64D and pepstatin A. In summary, these data suggested that facilitated acetaldehyde production via ADH following alcohol intake triggered cardiac autophagosome formation along with impaired lysosomal degradation, en route to myocardial defect.

  14. Pulmonary artery radiocardiography and rheography in the diagnosis of hemodynamic and contractile function impairments of the right ventricle in patients with obstructive bronchitis

    International Nuclear Information System (INIS)

    Paleev, N.P.; Cherejskaya, N.K.; Tsar'kova, L.N.; Baklykova, S.N.; Novoderezhkina, L.B.; Oblovatskaya, O.G.; Dubinina, E.B.

    1990-01-01

    Radiocardiography and rheography of the pulmonary artery were used to examine impairments in hemodynamics and contractile function of the right ventricle in 40 patients with chronic obstructive bronchitis complicated with persistent hypertension. Right ventricular hemodynamic and contractile impairments were shown to be not equivalent with similar clinical and functional signs of pulmonary hypertension. This fact indicates that the use of special techiques is of practical value in the determination of right ventricular hemodynamics and myocardial contractility in patients with chronic obstructive bronchitis. Radiocardiography and rheography of the pulmonary artery are sufficiently reliable noninvasive techniques for examining the hemodynamics and contractile function of the right ventricular myocardium

  15. Bladder contractility is modulated by Kv7 channels in pig detrusor

    DEFF Research Database (Denmark)

    Svalø, Julie; Bille, Michala; Parameswaran Theepakaran, Neeraja

    2013-01-01

    Kv7 channels are involved in smooth muscle relaxation, and accordingly we believe that they constitute potential targets for the treatment of overactive bladder syndrome. We have therefore used myography to examine the function of Kv7 channels in detrusor, i.e. pig bladder, with a view...... relaxation, suggesting that Kv7.2 and/or Kv7.4 channels constitute the subtypes that are relevant to bladder contractility. The effects of retigabine and ML213 were attenuated by pre-incubation with 10µM XE991 (Kv7.1-7.5 channel blocker) (P...

  16. A thermodynamical model for stress-fiber organization in contractile cells.

    Science.gov (United States)

    Foucard, Louis; Vernerey, Franck J

    2012-01-02

    Cell mechanical adaptivity to external stimuli is vital to many of its biological functions. A critical question is therefore to understand the formation and organization of the stress fibers from which emerge the cell's mechanical properties. By accounting for the mechanical aspects and the viscoelastic behavior of stress fibers, we here propose a thermodynamic model to predict the formation and orientation of stress fibers in contractile cells subjected to constant or cyclic stretch and different substrate stiffness. Our results demonstrate that the stress fibers viscoelastic behavior plays a crucial role in their formation and organization and shows good consistency with various experiments.

  17. CAPACIDAD PREDICTIVA DE MODELOS DE INSOLVENCIA CON BASE EN NÚMEROS CONTABLES Y DATOS DESCRIPTIVOS

    Directory of Open Access Journals (Sweden)

    Júlio Orestes da Silva

    2012-09-01

    Full Text Available En el Brasil la pesquisa sobre modelos de previsión de insolvencia se inició en la década de 1970, siendo que la mayor parte de los trabajos hizo uso del Análisis Discriminante como herramienta estadística del modelo. En los últimos años, se buscó verificar si es posible prever la insolvencia de las empresas utilizando datos descriptivos contenidos en los informes de las organizaciones. Así, este estudio tiene como objetivo verificar la capacidad de algunos modelos de previsión de insolvencia en prever la discontinuidad de empresas brasileñas que decretaron quiebra. La pesquisa se caracteriza como descriptiva y posee abordaje cuantitativo, realizado por medio de pesquisa documental. La muestra totalizó 13 empresas que decretaron quiebra entre los años de 1997 y 2003. Los resultados indican que la mayoría de los modelos de previsión de quiebra testados presentó resultados elevados de previsiones correctas. Los modelos de previsión de discontinuidad con base en informes descriptivos obtuvieron en media más previsiones asertivas en relación a la capacidad de prever la quiebra de las empresas. Esos descubrimientos demuestran que, a pesar de que algunas pesquisas apunten hacia la falta de validez de predictores creados en realidades empresariales diferentes, algunos modelos todavía poseen buena capacidad de previsión de insolvencia. Se concluye que tanto los modelos de previsión de insolvencia con base en números contables en relación a los modelos que se utilizan datos de informes descriptivos pueden prever la discontinuidad de las organizaciones. Por fin, se puede inferir que la mayoría de los modelos de previsión de quiebra que hacen uso de números contables pueden ser funcionales y capaces de prever la discontinuidad de las organizaciones.

  18. Factores de capacidad en el uso de control prenatal adecuado en gestantes de Sincelejo (Colombia

    Directory of Open Access Journals (Sweden)

    Clarybel Miranda Mellado

    2016-01-01

    Full Text Available Objetivo: Determinar los factores de capacidad relacionados con el uso adecuado de control prenatal en gestantes de Sincelejo (Colombia en 2014. Materiales y métodos: Estudio analítico de corte transversal, con una muestra de 730 gestantes, seleccionadas mediante muestreo por conglomerados. La información fue reco - lectada por medio de Encuesta Sociodemográfica y de Caracterización familiar, Escala de Apgar Familiar y Escala de Satisfacción con los Servicios Sanitarios. Para la tabulación de datos se usó Microsoft Excel V-2010, SPSSS V-17, y para el análisis, las pruebas OR y Análisis Multivariado. Resultados: El 97,7 % de las gestantes asiste al control prenatal. Sobre las razones de asistencia, 83,9 % (598 dijo que lo hacía para detectar alteraciones y 14,6 % (104 por recomendación de alguien; las 17 gestantes que no asistían al control citaron como razo - nes: porque deben hacer mucho trámite (47,1 %(8, por haber perdido la cita (23,5 %(4, porque creen no necesitar el control porque habían tenido hijos sin problemas (23,5 %(4, y porque creen que es muy temprano para iniciar el control (5,9 %(1. Acerca del uso de control prenatal se encontró que el 75,6 % (552 hace uso adecuado de este servicio. Conclusiones: Al hacer un análisis estadístico mediante razones de momios ( OR , para hallar asociación con los factores de capacidad, se encontró asociación estadísticamente significativa entre el uso adecuado de control prenatal y dos variables de capacidad: la afiliación a un régimen de salud y la satisfacción con los servicios de control prenatal.

  19. Treinamento aerobio e resistido, qualidade de vida e capacidade funcional de hipertensas

    Directory of Open Access Journals (Sweden)

    Thais Inacio Rolim Povoa

    2014-01-01

    Full Text Available INTRODUÇÃO: Pacientes hipertensos podem apresentar comprometimento da qualidade de vida (QV e da qualidade de vida relacionada à saúde (QVRS, tanto pela hipertensão arterial (HA, quanto pelos eventuais efeitos adversos do tratamento. Exercícios físicos, aeróbios e resistidos, melhoram a performance cardiorrespiratória e neuromuscular, mas há poucas evidências sobre seus efeitos na QV, QVRS e capacidade funcional (CF em mulheres hipertensas. OBJETIVO: Avaliar e comparar os efeitos dos treinamentos aeróbio e resistido sobre a QV, QVRS e a capacidade funcional em hipertensas. MÉTODOS: Ensaio clínico randomizado, cego, com total de 18 sessões de exercícios. Foram incluídas mulheres hipertensas sob tratamento medicamentoso, não participantes de programas de exercícios, com 50 anos de idade ou mais, que não apresentaram arritmias e/ou alterações isquêmicas em teste ergométrico (protocolo de Bruce. A amostra foi randomizada como segue: grupo aeróbio (GA (n = 21 e grupo resistido (GR (n = 20. Intensidade GA: leve a moderada (Escala de Borg adaptada; GR: até 50-65% de 1 RM. Duas séries com 12 a 15 repetições. Antes e após a intervenção foram aplicados os questionários WHOQOL-bref (QV e SF-36 (QVRS e realizado o teste de caminhada de 6 minutos (TC6` para avaliar a CF. Estatística: testes Shapiro-Wilk, t de Student, Fisher, U de Mann-Whitney e Wilcoxon. Nível de significância: p 0,05. Após a intervenção houve melhora significativa em todos os domínios do WHOQOL-bref no GA e no GR houve melhora no domínio aspectos físicos. No SF-36, constatou-se melhora significativa em sete de oito domínios tanto no GA quanto no GR. Capacidade funcional: verificou-se melhora nos dois grupos (p < 0,001. CONCLUSÃO: Os dois tipos de treinamento melhoraram a QV e a CF e, dependendo dos objetivos estabelecidos, ambos podem ser eficazes.

  20. Aportaciones a la evaluación de las Capacidades Físicas en la Educación Primaria

    OpenAIRE

    Velasco Martín, M.

    1994-01-01

    Una de las primeras misiones que debe tener el maestro es un conocimiento, lo más completo posible del niño, porque será la base para poder programar mejor y realizar su trabajo en la escuela. En educación física ese conocimiento viene dado por la Evaluación, entre otras, de las Capacidades Físicas Básicas. Se plantea qué pruebas y cuántas tenemos que hacer para evaluar esas Capacidades Físicas Básicas

  1. Capacidad transactivadora del gen pttg1 y su implicación en tumorigénesis

    OpenAIRE

    Romero Franco, Ana

    2016-01-01

    Falta palabras clave Objetivos: Los objetivos planteados en esta tesis doctoral son los que se enumeran a continuación: 1) Estudiar la capacidad moduladora que ejerce el gen pttg1 sobre la expresión de genes relacionados con el microambiente del tumor, en células inmortalizadas de ratón NIH3T3. 2) Estudiar la capacidad transactivadora del gen pttg1 en células tumorales humanas y establecer nexos con su posible implicación biológica en el desarrollo del tumor. 3) Estudiar el efecto en el de...

  2. Capacidade aerobia de futebolistas profissionais de altitude durante o periodo competitivo da cidade de Arequipa-Peru

    OpenAIRE

    Alejandro Inostroza Aeloiza

    2004-01-01

    Resumo: O objetivo do presente estudo foi de descrever e analisar a capacidade aeróbia de futebolistas profissionais de altitude durante o período competitivo, onde a seleção da amostra foi de tipo não-probabilístico 27 jogadores, para tal efeito, foram mensuradas as variáveis de massa corporal, estatura, quatro dobras cutâneas (triciptal, subescapular, supra- Ilíaca, e panturrilha), e para a capacidade aeróbia progressiva foi utilizado o teste físico de (corrida de ida e volta de 20m) de Nav...

  3. Definición y cálculo de la capacidad ambiental de una vía urbana

    OpenAIRE

    Aguilar Rovira, Mª del Mar

    2005-01-01

    Durante décadas se ha trabajado en las ciudades con volúmenes de tráfico relacionados con la capacidad física de los carriles destinados a la circulación, entendida como la máxima utilización del espacio viario disponible. La capacidad física va ligada al detrimento de necesidades de espacio para peatones, cilcistas y pasajeros de autobuses, además de contribuir a la contaminación atmosférica, acústica y a la accidentalidad que atenta contra la calidad y la movilidad urbana. Por eso define...

  4. À espera da seca que vem: capacidade adaptativa em comunidades rurais do semiárido

    OpenAIRE

    Mancal, Ansu; Lima, Patrícia Verônica Pinheiro Sales; Khan, Ahmad Saeed; Mayorga, Maria Irles de Oliveira

    2016-01-01

    Este artigo avalia a disponibilidade de recursos necessários para criação de capacidade adaptativa em comunidades rurais do semiárido brasileiro. A pesquisa utiliza dados primários obtidos por meio de aplicação de questionários. Dada a grande extensão geográfica da região, adota-se como recorte uma amostra de comunidades rurais inseridas em áreas susceptíveis à desertificação no Estado do Ceará. A discussão é feita a partir de um sistema de indicadores definido por meio de consultas a especia...

  5. Instrumento para avaliação da capacidade de autocuidado de pacientes adultos: CADEM

    Directory of Open Access Journals (Sweden)

    Denise Costa Dias

    1996-09-01

    Full Text Available Este estudo trata do desenvolvimento de um instrumento para facilitar a determinação da capacidade de autocuidado de pacientes adultos, tendo como finalidade a promoção de linguagem clara e objetiva. O instrumento desenvolvido, chamado CADEM, estabelece níveis para determinar a categorização dos pacientes segundo a necessidade de cuidados de enfermagem. Considerou-se que o CADEM é um instrumento válido e que pode auxiliar no planejamento da assistência de enfermagem, e também documentar a evolução do paciente através de sua aplicação sistemática e continuada, servindo de subsídio para embasar mudanças necessárias no plano de cuidados dos pacientes.

  6. La capacidad de actualizar información inferencial en la lectura

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    Ana I. Pérez Muñoz

    2013-10-01

    Full Text Available Durante la comprensión lectora, el proceso de actualización inferencial nos permite sustituir una idea del texto que hayamos generado equívocamente por otra más plausible que aún está por confirmar. Esta habilidad parece depender de nuestra capacidad de Memoria de Trabajo, la cual nos ayuda a mantener una representación coherente de lo que estamos leyendo, mientras que comprendemos la información posterior y descartamos ideas que hemos podido interpretar de forma errónea. El entrenamiento en actualización inferencial a edades tempranas podría beneficiar la comprensión lectora de textos a lo largo de toda la vida.

  7. Capacidad predictiva del apoyo social en la inteligencia emocional de adolescentes

    Directory of Open Access Journals (Sweden)

    Lorea Azpiazu

    2015-06-01

    Full Text Available El objetivo de este estudio es analizar la relación entre el apoyo social (familiar, amistades y profesorado y la inteligencia emocional (atención, claridad y reparación. La muestra está compuesta por 1543 adolescentes, 728 chicos (47.18% y 815 chicas (52.81%, entre los 11 y 18 años (Medad = 14.24, DT = 1.63. Los análisis estadísticos se llevan a cabo con el programa SPSS 21 para Windows. Los resultados del análisis correlacional señalan que el apoyo social y la inteligencia emocional están significativamente relacionados en ambos sexos. Por otro lado, el análisis de regresión demuestra la capacidad predictiva de los diferentes apoyos en la inteligencia emocional tanto en la muestra masculina como en la femenina.

  8. LOS RECURSOS FINANCIEROS INVERTIDOS EN LA OPERACIÓN Y CAPACIDAD INSTALADA EN LAS ORGANIZACIONES

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    Juan Gaytán Cortés

    2018-02-01

    Full Text Available El definir y analizar el concepto el concepto de recursos utilizados por las organizaciones, utilizando como apoyo la teoría de recursos y capacidades, ha enfrentado fuertes diferencias tomando en consideración la clase y combinación de recursos utilizados no sólo entre empresas de la misma industria sino también dentro de los límites más estrechos de los grupos de la misma industria.  Esto sugiere que los efectos de los recursos individuales, específicos de las empresas sobre la rentabilidad o desempeño financiero pueden ser muy significativos, (Mahoney y Pandian 1992. (Hansen y Wernerfelt 1989, (Cool y Schendel, 1988.

  9. Entrenamiento de la capacidad de salto en el jugador de baloncesto: una revisión

    Directory of Open Access Journals (Sweden)

    Jaime San Román-Quintana

    2011-01-01

    Full Text Available El baloncesto es un deporte intermitente en el que se combinan acciones de intensidad leve, moderada y alta y por tanto el metabolismo aeróbico y anaeróbico se presentan conjuntamente. Una de las acciones más determinantes durante la competición es la capacidad de salto, dado que es utilizada por los jugadores para ejecutar, a su vez, diferentes situaciones específicas del juego como tirar o entrar a canasta, etc., sugiriéndose así, que dicha Expresión de la fuerza es un factor principal en el éxito en este deporte. Por ello, el entrenamiento del salto vertical en el jugador de baloncesto es una cuestión determinante en el rendimiento final del juego.

  10. A stepwise procedure to test contractility and susceptibility to injury for the rodent quadriceps muscle

    Directory of Open Access Journals (Sweden)

    Stephen J.P. Pratt

    2014-07-01

    Full Text Available In patients with muscle injury or muscle disease, assessment of muscle damage is typically limited to clinical signs, such as tenderness, strength, range of motion, and more recently, imaging studies.  Biological markers can also be used in measuring muscle injury, such as increased creatine kinase levels in the blood, but these are not always correlated with loss in muscle function (i.e. loss of force production.  This is even true of histological findings from animals, which provide a “direct measure” of damage, but do not account for loss of function.  The most comprehensive measure of the overall health of the muscle is contractile force.  To date, animal models testing contractile force have been limited to the muscle groups moving the ankle.  Here we describe an in vivo animal model for the quadriceps, with abilities to measure torque, produce a reliable muscle injury, and follow muscle recovery within the same animal over time.  We also describe a second model used for direct measurement of force from an isolated quadriceps muscle in situ. 

  11. Influence of intracellular acidosis on contractile function in the working rat heart

    International Nuclear Information System (INIS)

    Jeffrey, F.M.H.; Malloy, C.R.; Radda, G.K.

    1987-01-01

    The decrease in myocardial contractility during ischemia, hypoxia, and extracellular acidosis has been attributed to intracellular acidosis. Previous studies of the relationship between pH and contractile state have utilized respiratory or metabolic acidosis to alter intracellular pH. The authors developed a model in the working perfused rat heart to study the effects of intracellular acidosis with normal external pH and optimal O 2 delivery. Intracellular pH and high-energy phosphates were monitored by 31 P nuclear magnetic resonance spectroscopy. Hearts were perfused to a steady state with a medium containing 10 mM NH 4 Cl. Acidosis induced a substantial decrease in aortic flow and stroke volume which was associated with little change in peak systolic pressure. It was concluded that (1) for the same intracellular acidosis the influence on tension development was more pronounced with a combined extra- and intracellular acidosis than with an isolated intracellular acidosis, and (2) stroke volume at constant preload was impaired by intracellular acidosis even though changes in developed pressure were minimal. These observations suggest that isolated intracellular acidosis has adverse effects on diastolic compliance and/or relaxation

  12. Oscillatory behaviors and hierarchical assembly of contractile structures in intercalating cells

    International Nuclear Information System (INIS)

    Fernandez-Gonzalez, Rodrigo; Zallen, Jennifer A

    2011-01-01

    Fluctuations in the size of the apical cell surface have been associated with apical constriction and tissue invagination. However, it is currently not known if apical oscillatory behaviors are a unique property of constricting cells or if they constitute a universal feature of the force balance between cells in multicellular tissues. Here, we set out to determine whether oscillatory cell behaviors occur in parallel with cell intercalation during the morphogenetic process of axis elongation in the Drosophila embryo. We applied multi-color, time-lapse imaging of living embryos and SIESTA, an integrated tool for automated and semi-automated cell segmentation, tracking, and analysis of image sequences. Using SIESTA, we identified cycles of contraction and expansion of the apical surface in intercalating cells and characterized them at the molecular, cellular, and tissue scales. We demonstrate that apical oscillations are anisotropic, and this anisotropy depends on the presence of intact cell–cell junctions and spatial cues provided by the anterior–posterior patterning system. Oscillatory cell behaviors during axis elongation are associated with the hierarchical assembly and disassembly of contractile actomyosin structures at the medial cortex of the cell, with actin localization preceding myosin II and with the localization of both proteins preceding changes in cell shape. We discuss models to explain how the architecture of cytoskeletal networks regulates their contractile behavior and the mechanisms that give rise to oscillatory cell behaviors in intercalating cells

  13. Dependence of intramyocardial pressure and coronary flow on ventricular loading and contractility: a model study.

    Science.gov (United States)

    Bovendeerd, Peter H M; Borsje, Petra; Arts, Theo; van De Vosse, Frans N

    2006-12-01

    The phasic coronary arterial inflow during the normal cardiac cycle has been explained with simple (waterfall, intramyocardial pump) models, emphasizing the role of ventricular pressure. To explain changes in isovolumic and low afterload beats, these models were extended with the effect of three-dimensional wall stress, nonlinear characteristics of the coronary bed, and extravascular fluid exchange. With the associated increase in the number of model parameters, a detailed parameter sensitivity analysis has become difficult. Therefore we investigated the primary relations between ventricular pressure and volume, wall stress, intramyocardial pressure and coronary blood flow, with a mathematical model with a limited number of parameters. The model replicates several experimental observations: the phasic character of coronary inflow is virtually independent of maximum ventricular pressure, the amplitude of the coronary flow signal varies about proportionally with cardiac contractility, and intramyocardial pressure in the ventricular wall may exceed ventricular pressure. A parameter sensitivity analysis shows that the normalized amplitude of coronary inflow is mainly determined by contractility, reflected in ventricular pressure and, at low ventricular volumes, radial wall stress. Normalized flow amplitude is less sensitive to myocardial coronary compliance and resistance, and to the relation between active fiber stress, time, and sarcomere shortening velocity.

  14. Modulation of cardiac contractility by the phospholamban/SERCA2a regulatome.

    Science.gov (United States)

    Kranias, Evangelia G; Hajjar, Roger J

    2012-06-08

    Heart disease remains the leading cause of death and disability in the Western world. Current therapies aim at treating the symptoms rather than the subcellular mechanisms, underlying the etiology and pathological remodeling in heart failure. A universal characteristic, contributing to the decreased contractile performance in human and experimental failing hearts, is impaired calcium sequestration into the sarcoplasmic reticulum (SR). SR calcium uptake is mediated by a Ca(2+)-ATPase (SERCA2), whose activity is reversibly regulated by phospholamban (PLN). Dephosphorylated PLN is an inhibitor of SERCA and phosphorylation of PLN relieves this inhibition. However, the initial simple view of a PLN/SERCA regulatory complex has been modified by our recent identification of SUMO, S100 and the histidine-rich Ca-binding protein as regulators of SERCA activity. In addition, PLN activity is regulated by 2 phosphoproteins, the inhibitor-1 of protein phosphatase 1 and the small heat shock protein 20, which affect the overall SERCA-mediated Ca-transport. This review will highlight the regulatory mechanisms of cardiac contractility by the multimeric SERCA/PLN-ensemble and the potential for new therapeutic avenues targeting this complex by using small molecules and gene transfer methods.

  15. Effects of Silodosin and Tamsulosin on the Seminal Vesicle Contractile Response.

    Science.gov (United States)

    Hayashi, Tokumasa; Takeya, Mitsue; Nakamura, Kei-ichiro; Matsuoka, Kei

    2016-01-01

    To understand the mechanisms underlying ejaculation dysfunction caused by α1A-adrenocetor (AR) antagonists, the effects of α1A-AR antagonists on the contractile responses of the seminal vesicle were investigated. Isolated seminal vesicles from guinea pigs were cannulated and pressurized, and the changes in the intraluminal pressure were recorded. Periodic applications of electrical stimulation (ES) caused biphasic increase in the intraluminal pressure, that is, initial and subsequent contractions. The effects of silodosin and tamsulosin, α1A-AR antagonists, on the contractile responses were examined. The ES-induced biphasic contractions were blocked by tetrodotoxin (TTX). Silodosin and tamsulosin suppressed the initial contractions in a dose-dependent manner, while also exerting various inhibitory effects on the subsequent contractions. Increases in the intraluminal pressure facilitated spontaneous phasic contractions. The spontaneous contractions were not affected by TTX or α1A-AR antagonists, but were abolished by nifedipine. The initial contractions triggered by neuronal excitations were suppressed by silodosin and tamsulosin, suggesting that the ejaculation dysfunction may be attributed to the α1A-AR antagonist-mediated suppression of nerve-evoked contractions in the seminal vesicle. The subsequent contractions may be induced by mechanical stimulation associated with the initial, nerve-evoked contractions. Alternatively, other transmitters may be involved to various degrees in the neuromuscular transmission of the seminal vesicle. © 2014 Wiley Publishing Asia Pty Ltd.

  16. Dietary nitrate increases tetanic [Ca2+]i and contractile force in mouse fast-twitch muscle.

    Science.gov (United States)

    Hernández, Andrés; Schiffer, Tomas A; Ivarsson, Niklas; Cheng, Arthur J; Bruton, Joseph D; Lundberg, Jon O; Weitzberg, Eddie; Westerblad, Håkan

    2012-08-01

    Dietary inorganic nitrate has profound effects on health and physiological responses to exercise. Here, we examined if nitrate, in doses readily achievable via a normal diet, could improve Ca(2+) handling and contractile function using fast- and slow-twitch skeletal muscles from C57bl/6 male mice given 1 mm sodium nitrate in water for 7 days. Age matched controls were provided water without added nitrate. In fast-twitch muscle fibres dissected from nitrate treated mice, myoplasmic free [Ca(2+)] was significantly greater than in Control fibres at stimulation frequencies from 20 to 150 Hz, which resulted in a major increase in contractile force at ≤ 50 Hz. At 100 Hz stimulation, the rate of force development was ∼35% faster in the nitrate group. These changes in nitrate treated mice were accompanied by increased expression of the Ca(2+) handling proteins calsequestrin 1 and the dihydropyridine receptor. No changes in force or calsequestrin 1 and dihydropyridine receptor expression were measured in slow-twitch muscles. In conclusion, these results show a striking effect of nitrate supplementation on intracellular Ca(2+) handling in fast-twitch muscle resulting in increased force production. A new mechanism is revealed by which nitrate can exert effects on muscle function with applications to performance and a potential therapeutic role in conditions with muscle weakness.

  17. Dynamics of myosin II organization into cortical contractile networks and fibers

    Science.gov (United States)

    Nie, Wei; Wei, Ming-Tzo; Ou-Yang, Daniel; Jedlicka, Sabrina; Vavylonis, Dimitrios

    2014-03-01

    The morphology of adhered cells critically depends on the formation of a contractile meshwork of parallel and cross-linked stress fibers along the contacting surface. The motor activity and mini-filament assembly of non-muscle myosin II is an important component of cell-level cytoskeletal remodeling during mechanosensing. To monitor the dynamics of myosin II, we used confocal microscopy to image cultured HeLa cells that stably express myosin regulatory light chain tagged with GFP (MRLC-GFP). MRLC-GFP was monitored in time-lapse movies at steady state and during the response of cells to varying concentrations of blebbistatin which disrupts actomyosin stress fibers. Using image correlation spectroscopy analysis, we quantified the kinetics of disassembly and reassembly of actomyosin networks and compared them to studies by other groups. This analysis suggested that the following processes contribute to the assembly of cortical actomyosin into fibers: random myosin mini-filament assembly and disassembly along the cortex; myosin mini-filament aligning and contraction; stabilization of cortical myosin upon increasing contractile tension. We developed simple numerical simulations that include those processes. The results of simulations of cells at steady state and in response to blebbistatin capture some of the main features observed in the experiments. This study provides a framework to help interpret how different cortical myosin remodeling kinetics may contribute to different cell shape and rigidity depending on substrate stiffness.

  18. Evolutionarily conserved sites in yeast tropomyosin function in cell polarity, transport and contractile ring formation

    Directory of Open Access Journals (Sweden)

    Susanne Cranz-Mileva

    2015-08-01

    Full Text Available Tropomyosin is a coiled-coil protein that binds and regulates actin filaments. The tropomyosin gene in Schizosaccharomyces pombe, cdc8, is required for formation of actin cables, contractile rings, and polar localization of actin patches. The roles of conserved residues were investigated in gene replacement mutants. The work validates an evolution-based approach to identify tropomyosin functions in living cells and sites of potential interactions with other proteins. A cdc8 mutant with near-normal actin affinity affects patch polarization and vacuole fusion, possibly by affecting Myo52p, a class V myosin, function. The presence of labile residual cell attachments suggests a delay in completion of cell division and redistribution of cell patches following cytokinesis. Another mutant with a mild phenotype is synthetic negative with GFP-fimbrin, inferring involvement of the mutated tropomyosin sites in interaction between the two proteins. Proteins that assemble in the contractile ring region before actin do so in a mutant cdc8 strain that cannot assemble condensed actin rings, yet some cells can divide. Of general significance, LifeAct-GFP negatively affects the actin cytoskeleton, indicating caution in its use as a biomarker for actin filaments.

  19. Dynamics of myosin II organization into contractile networks and fibers at the medial cell cortex

    Science.gov (United States)

    Nie, Wei

    The cellular morphology of adhered cells depends crucially on the formation of a contractile meshwork of parallel and cross-linked stress fibers along the contacting surface. The motor activity and mini-filament assembly of non-muscle myosin II is an important component of cell-level cytoskeletal remodeling during mechanosensing. To monitor the dynamics of non-muscle myosin II, we used confocal microscopy to image cultured HeLa cells that stably express myosin regulatory light chain tagged with GFP (MRLC-GFP). MRLC-GFP was monitored in time-lapse movies at steady state and during the response of cells to varying concentrations of blebbistatin (which disrupts actomyosin stress fibers). Using image correlation spectroscopy analysis, we quantified the kinetics of disassembly and reassembly of actomyosin networks and compared to studies by other groups. This analysis suggested the following processes: myosin minifilament assembly and disassembly; aligning and contraction; myosin filament stabilization upon increasing contractile tension. Numerical simulations that include those processes capture some of the main features observed in the experiments. This study provides a framework to help interpret how different cortical myosin remodeling kinetics may contribute to different cell shape and rigidity depending on substrate stiffness. We discuss methods to monitor myosin reorganization using non-linear imaging methods.

  20. EFFECT OF HYDROGEN SULFIDE ON ATRIUM CONTRACTILITY IN CONTROL AND DIABETHIC MICE

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    A. S. Lifanova

    2014-01-01

    Full Text Available Hydrogen sulfide (H2S is endogenously synthesized gasotransmitter that has a regulatory effect in cardiovascular system. Diabetes mellitus leads to an increased risk of hypertension and cardiovascular diseases, so the purpose of the study was to analyze the contractility of the atria mice after application of L-cysteine and H2S. Contractile activity of the myocardium was investigated in the experiment on isolated mouse atria. Alloxan was used for modeling diabetes. Intraperitoneal injection of alloxan resulted in a significant increase of glucose concentration in blood, whereas the concentration of glucose didn’t change at the injection of physiological solution. In control, the addition of NaHS resulted in a significant dose-dependent decrease of the amplitude of contraction of the myocardium, whereas the negative inotropic effect of NaHS was significantly lower in terms of modeling diabetes compare to control conditions. In the control, L-cysteine reduced the amplitude contractions significantly, whereas L-cysteine did not lead to significant changes in the amplitude of contractions in terms of modeling diabetes. These data indicate that the sensitivity of mice’s atria reduced for H2S and L-cysteine in diabetes mellitus.

  1. The effectiveness of two novel techniques in establishing the mechanical and contractile responses of biceps femoris

    International Nuclear Information System (INIS)

    Ditroilo, Massimiliano; De Vito, Giuseppe; Hunter, Angus M; Haslam, Samuel

    2011-01-01

    Portable tensiomyography (TMG) and myotonometry (MMT) devices have been developed to measure mechanical and contractile properties of skeletal muscle. The aim of this study was to explore the sensitivity of the aforementioned techniques in detecting a change in passive mechanical properties of the biceps femoris (BF) muscle as a result of change in knee joint angle (i.e. muscle length). BF responses were assessed in 16 young participants (23.4 ± 4.9 years), at three knee joint angles (0°, 45° and 90°), for maximal isometric torque (MIT) along with myo-electrical activity. Contractile and mechanical properties were measured in a relaxed state. Inter-day reliability of the TMG and MMT was also assessed. MIT changed significantly (p < 0.01) across the three angles, so did stiffness and other parameters measured with MMT (p < 0.01). Conversely, TMG could detect changes only at two knee angles (0° and 45°, p < 0.01), when there is enough tension in the muscle. Reliability was overall insufficient for TMG whilst absolute reliability was excellent (coefficient of variation < 5%) for MMT. The ability of MMT more than TMG to detect an inherent change in stiffness can be conceivably exploited in a number of clinical/therapeutic applications that have to do with unnatural changes in passive muscle stiffness

  2. Scintigraphic measurement of the contractile activity of the gastric antrum using factor analysis

    International Nuclear Information System (INIS)

    Bergmann, H.; Hoebart, J.; Kugi, A.; Stacher, G.; Granser, G.V.

    1990-01-01

    The motor activity of the gastric antrum is difficult to record by manometric means and scintigraphic methods have proved unsatisfactory so far as no consistent relationship between antral contractile activity and gastric emptying rate could be detected. We investigated, using data recorded in 16 healthy human subjects after the ingestion of a semisolid standard meal, whether a newly developed method employing factor analysis would yield more meaningful and reproducible results. Factor analysis was applied to sequential scintigraphic images (3-s frame time) of gastric antrum. The computed factor images and the respective factor curves are representative of distinct dynamic structures of the antrum. From the more or less sinusoidal excursions of the factor curves, which exhibited the 3 cycles per minute frequency characteristic for the stomach, amplitude, frequency and propagation velocity of antral contractions can be calculated. The amplitudes of the factor curves were used to calculate a contraction index. This contraction index was found to be correlated significantly negatively with the gastric half-emptying time of the ingested meal. The employed factor analytical approach thus seems a promising tool to further investigate the role of antral contractility in the process of gastric emptying. (Authors)

  3. Izalpinin from fruits of Alpinia oxyphylla with antagonistic activity against the rat bladder contractility.

    Science.gov (United States)

    Yuan, Yuan; Tan, Yin-Feng; Xu, Peng; Li, Hailong; Li, Yong-Hui; Chen, Wen-Ya; Zhang, Jun-Qing; Chen, Feng; Huang, Guo-Jun

    2014-01-01

    Alpinia oxyphylla (Zingiberaceae), an herbaceous perennial plant, its capsular fruit is commonly used in traditional Chinese medicine for the treatment of different urinary incontinence symptoms including frequency, urgency and nocturia. These symptoms are similar to the overactive bladder syndrome. In our lab, we found that the 95% ethanol extract of the capsular fruits exhibited significant anti-muscarinic activity. Some constituents in capsular fruits including flavonoids (e.g., izalpinin and tectochrysin), diarylheptanoids (e.g., yakuchinone A and yakuchinone B) and sesquiterpenes (e.g., nootkatone), are regarded as representative chemicals with putative pharmacological activities. This study aimed to evaluate the in vitro antagonistic actions of izalpinin on carbachol-induced contraction of the rat detrusor muscle. In vitro inhibition of rat detrusor contractile response to carbachol was used to study the functional activity of izalpinin. The isolated detrusor strips of rats were mounted in organ baths containing oxygenated Krebs' solution. The cumulative consecutive concentration-response curves to carbachol-evoked contractions in strips of rat bladder were obtained. Carbachol induced concentration-dependent contractions of isolated rat bladder detrusor strips. The vehicle DMSO had no impact on the contraction response. The contraction effects were concentration-dependently antagonized by izalpinin, with a mean EC50 value of 0.35 µM. The corresponding cumulative agonist concentration-response curves shifted right-ward. Izalpinin exhibits inhibitory role of muscarinic receptor-related detrusor contractile activity, and it may be a promising lead compound to treat overactive bladder.

  4. PPARγ Ligands Regulate Noncontractile and Contractile Functions of Airway Smooth Muscle: Implications for Asthma Therapy

    Directory of Open Access Journals (Sweden)

    Chantal Donovan

    2012-01-01

    Full Text Available In asthma, the increase in airway smooth muscle (ASM can contribute to inflammation, airway wall remodeling and airway hyperresponsiveness (AHR. Targetting peroxisome proliferator-activated receptor γ (PPARγ, a receptor upregulated in ASM in asthmatic airways, may provide a novel approach to regulate these contributions. This review summarises experimental evidence that PPARγ ligands, such as rosiglitazone (RGZ and pioglitazone (PGZ, inhibit proliferation and inflammatory cytokine production from ASM in vitro. In addition, inhaled administration of these ligands reduces inflammatory cell infiltration and airway remodelling in mouse models of allergen-induced airways disease. PPARγ ligands can also regulate ASM contractility, with acute treatment eliciting relaxation of mouse trachea in vitro through a PPARγ-independent mechanism. Chronic treatment can protect against the loss of bronchodilator sensitivity to β2-adrenoceptor agonists and inhibit the development of AHR associated with exposure to nicotine in utero or following allergen challenge. Of particular interest, a small clinical trial has shown that oral RGZ treatment improves lung function in smokers with asthma, a group that is generally unresponsive to conventional steroid treatment. These combined findings support further investigation of the potential for PPARγ agonists to target the noncontractile and contractile functions of ASM to improve outcomes for patients with poorly controlled asthma.

  5. Long-term vascular contractility assay using genipin-modified muscular thin films

    International Nuclear Information System (INIS)

    Hald, Eric S; Steucke, Kerianne E; Reeves, Jack A; Win, Zaw; Alford, Patrick W

    2014-01-01

    Vascular disease is a leading cause of death globally and typically manifests chronically due to long-term maladaptive arterial growth and remodeling. To date, there is no in vitro technique for studying vascular function over relevant disease time courses that both mimics in vivo-like tissue structure and provides a simple readout of tissue stress. We aimed to extend tissue viability in our muscular thin film contractility assay by modifying the polydimethylsiloxane (PDMS) substrate with micropatterned genipin, allowing extracellular matrix turnover without cell loss. To achieve this, we developed a microfluidic delivery system to pattern genipin and extracellular matrix proteins on PDMS prior to cell seeding. Tissues constructed using this method showed improved viability and maintenance of in vivo-like lamellar structure. Functional contractility of tissues fabricated on genipin-modified substrates remained consistent throughout two weeks in culture. These results suggest that muscular thin films with genipin-modified PDMS substrates are a viable method for conducting functional studies of arterial growth and remodeling in vascular diseases. (paper)

  6. Comportamientos y capacidad de agencia de autocuidado de adultos con insuficiencia cardiaca

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    EDITH ARREDONDO HOLGUÍN

    2010-06-01

    Full Text Available Este estudio tiene como objetivo describir comportamientos y capacidad de agencia de autocuidado de pacientes con insuficiencia cardiaca de una clínica cardiovascular de Medellín entre noviembre de 2007 y mayo de 2008. Es un estudio descriptivo con abordaje cuantitativo. La muestra fue de 206 adultos con insuficiencia cardiaca diagnosticados por sintomatología clínica, fracción de eyección menor o igual a 40%. Se usaron para la recolección de datos la Escala Capacidad de Agencia de Autocuidado desarrollada por Isemberg y Evers et ál. (1993, traducida por Gallego, que mide el nivel de agencia de autocuidado, y la Escala Comportamientos de Autocuidado validada en Colombia en 2007 por Arredondo, que mide la frecuencia de comportamientos de autocuidado de adultos con insuficiencia cardiaca en la solicitud de ayuda, adaptación a vivir con la enfermedad y el régimen terapéutico, modificación del autoconcepto y aceptación de sí mismo, vivir con efectos de la insuficiencia cardiaca y el tratamiento. Concluye que el mayor número de pacientes eran hombres; que factores básicos condicionantes como el apoyo de la familia, desempeño de un trabajo, afiliación al sistema de salud, nivel socioeconómico y acceso a un nivel educativo fueron importantes para los pacientes. La frecuencia de comportamientos de autocuidado fue media en los adultos en la mayoría de las dimensiones y el nivel de agencia fue alto y muy alto. Igualmente se concluyó que no hay una correlación entre agencia y comportamientos de autocuidado. Lo que plantea que los adultos tienen el conocimiento pero no han tomado la decisión de realizar acciones de autocuidado.

  7. CAPACIDAD ANTAGONISTA DE HONGOS CELULOLÍTICOS FRENTE A Fusarium sp. Y Macrophomina sp.

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    Néstor Leopoldo Tarazona Meza

    2014-12-01

    Full Text Available El objetivo de esta investigación fue evaluar la capacidad antagónica de ocho hongos celulolíticos nativos frente a los hongos fitopatógenos Fusarium sp. y Macrophomina sp. En primera instancia se determinó la cepa promisoria del hongo celulolítico, para lo cual, en caja Petri se colocó un disco de agar de 4 mm de diámetro con micelio de una cepa antagonista y en el extremo opuesto, a una distancia de cinco centímetros aproximadamente, otro disco de 4 mm con micelio de un patógeno. La capacidad antagónica se determinó por el grado de micoparasitismo y la competencia por nutrientes y espacios, registrando el porcentaje de inhibición del crecimiento radial. Con la cepa del hongo celulolítico que tuvo el mejor comportamiento antagonista se realizó un cocultivo independiente con cada patógeno, aquí se evalúo las UFC, crecidas en medio PDA. También se inoculó junto a las cepas fitopatógenas en plantas de pimiento para conocer el nivel de antagonismo en macetas. En la evaluación cualitativa, la cepa A.O-5 mostró una invasión y esporulación total en la superficie en ambos patógenos; mientras que en el cocultivo inhibe el crecimiento de los patógenos a las 96 h. Igualmente demostró su acción antagonista frente a Fusarium y Macrophomina en las plántulas de pimiento. Por lo encontrado, se estima que la cepa A.O-5 es un potencial agente antagonista de los fitopatógenos evaluados.

  8. Estudio de la capacidad para intumescer de dos sistemas de pintura expuestos a ambientes internos agresivos

    Directory of Open Access Journals (Sweden)

    Chico, B.

    2005-12-01

    Full Text Available The influence exerted by temperature on the resistant capacity of structural steel is well known. A highly efficient protection system for steel consists of the application of intumescent paints. In the case of fire, their effectiveness is based on the property that when they come into contact with flames they react by swelling to form an insulating layer, referred to as "intumescence", which impedes the propagation of heat. These paints do not require continuous maintenance though their service behaviour depends on the exposure conditions to which they are exposed. This paper studies the behaviour of two acrylated rubber type intumescent systems exposed to a galvanising plant for 16 months, evaluating the effect of the environment on the capacity to intumesce of the coating when subjected to heating.

    Es conocida la influencia que ejerce la temperatura en la capacidad resistente del acero estructural. Un sistema de protección del acero, altamente efectivo, consiste en la utilización de pinturas intumescentes. Su efectividad se basa en el hecho de que, en el caso eventual de un incendio, al entrar en contacto con la llama reaccionan hinchándose y formando una capa aislante que se denomina "intumescencia" y que impide la propagación del calor. Estas pinturas no precisan de un mantenimiento continuo, aunque su comportamiento en servicio depende de las condiciones de exposición. Este trabajo estudia el comportamiento de dos sistemas intumescentes de tipo caucho acrilado expuestos en una planta de galvanizado durante 16 meses, valorando el efecto del medio ambiente sobre la capacidad para intumescer del recubrimiento cuando es sometido a un calentamiento.

  9. PLANIFICACIÓN JERÁRQUICA CON ANÁLISIS DE CARGA-CAPACIDAD

    Directory of Open Access Journals (Sweden)

    Tulio Gerardo Motoa

    2001-01-01

    Full Text Available

    La planificación jerárquica de múltiples proyectos, surge como una opción robusta y potente, para resolver el problema de gestión del sistema global. La propuesta se basa en la construcción de una estructura de descomposición-agregación de los proyectos y los recursos, con múltiples niveles, en la cual, los niveles más altos presentan los datos más agregados, con horizontes de tiempo más largos y los niveles inferiores son más detallados y con horizontes más cortos. Dentro del ámbito de la planificación jerárquica, el análisis de carga-capacidad pretende fundamentalmente mejorar la relación entre la oferta y la demanda de recursos en los procesos de planificación de proyectos, de tal manera que se garantice el cumplimiento de las fechas ya establecidas. Este análisis, se implementa midiendo algunos indicadores que reflejan el estado de la relación entre la carga y la capacidad y ejecutando un procedimiento de nivelación que avanza en el equilibrio de tal estado. El procedimiento de análisis se ha experimentado mediante un conjunto de proyectos generados aleatoriamente y los resultados son bastante buenos.

  10. ¿Es posible potenciar la capacidad de liderazgo en la universidad?

    Directory of Open Access Journals (Sweden)

    C. Delia Dávila Quintana

    2015-04-01

    Full Text Available El objetivo del trabajo es analizar la importancia de la educación superior, concretamente de los métodos de enseñanza-aprendizaje, en el comportamiento posterior de los graduados en el puesto de trabajo en relación a tres dimensiones del liderazgo: liderazgo orientado a las tareas, a las relaciones y al cambio. Las competencias profesionales desarrolladas por los graduados durante sus estudios son el canal de transmisión desde la educación al futuro desempeño como líderes. Para ello se estimaron modelos de ecuaciones estructurales (SEM con una muestra de aproximadamente 3.500 jóvenes graduados por universidades españolas provenientes de la base de datos reflex. Los resultados obtenidos indican que el comportamiento como líderes en las tres dimensiones analizadas depende crucialmente del nivel competencial de los individuos en determinadas competencias clave. Las competencias relacionadas con la capacidad de liderazgo son desarrolladas durante los estudios universitarios y posteriormente ampliadas a través de la experiencia y formación en el puesto. El análisis también identifica los métodos de enseñanza-aprendizaje que presentan una mayor influencia en el desarrollo de las competencias para el liderazgo. La principal implicación del análisis consiste en que un entorno educativo adecuado puede favorecer la adquisición durante los estudios de las competencias necesarias para el ejercicio de la capacidad de liderazgo, lo que a su vez favorece el desarrollo posterior de estas mismas competencias en las primeras experiencias laborales, incrementando así la propensión de los graduados a actuar efectivamente como líderes en las organizaciones para las que trabajan en las tres dimensiones del liderazgo analizadas.

  11. Capacidade estatal, burocracia e tributação nos municípios brasileiros

    Directory of Open Access Journals (Sweden)

    André Marenco

    Full Text Available Resumo Diagnósticos sobre relações intergovernamentais e implementação de políticas públicas após a Constituição de 1988 enfatizaram os elementos de descentralização, centralização ou coordenação federativa. Sem desprezar mecanismos institucionais que estruturam relações verticais entre governos federal, estadual e municipais, este trabalho pretende analisar diferenças entre os 5,5 mil municípios brasileiros no que diz respeito a indicadores de sua capacidade estatal. Busca-se examinar em que medida municípios com burocracias profissionalizadas tiveram melhores condições para aproveitar a transferência de responsabilidades e autoridade política e administrativa para governos municipais, ampliando seu potencial para tributar e implementar políticas públicas. Adotou-se a definição restrita de capacidade estatal, utilizando-se a “escala weberiana” proposta por Evans e Rauch como medida. Para operacionalizá-la, foi considerada a proporção de “estatutários com formação superior” entre servidores públicos nas 5,5 mil administrações municipais brasileiras. Como variável dependente, foi utilizada a arrecadação de Imposto sobre a Propriedade Predial e Territorial Urbana como proporção da receita própria municipal. Os resultados mostraram que administrações municipais com serviço público mais profissionalizado incrementam suas razões de chance para arrecadação do imposto patrimonial.

  12. Endothelin-1 and endothelin-2 initiate and maintain contractile responses by different mechanisms in rat mesenteric and cerebral arteries

    DEFF Research Database (Denmark)

    Compeer, M. G.; Janssen, G. M. J.; De Mey, J. G. R.

    2013-01-01

    , but relaxed ET-1-induced contractions in MRA. A PLC inhibitor prevented contractile responses to ET-1 and ET-2 in MRA and BA, and relaxed ET-1- and ET-2-induced responses in MRA and ET-1 effects in BA. A Rho-kinase inhibitor did not modify sensitivity, maximum and maintenance of responses to both peptides...... in both arteries but relaxed ET-2, but not ET-1, effects in MRA and ET-1 effects in BA. Conclusions and ImplicationsPLC played a key role in arterial contractile responses to ETs, but ET-1 and ET-2 initiated and maintained vasoconstriction through different mechanisms, and these differed between MRA...

  13. Compostos fenólicos e capacidade antioxidante em frutos de tomateiros mutantes fotomorfogenéticos

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    Tiago Dias

    2015-05-01

    Full Text Available Compostos fenólicos e capacidade antioxidante são mecanismos de defesa das plantas aos danos do estresse oxidativo. Os compostos fenólicos são sintetizados pela via dos fenilpropanoides, cuja enzima chave, fenilalanina amônia liase, é influenciada pela luz e ação de fotorreceptores, como o fitocromo. O objetivo do presente trabalho é avaliar a concentração de compostos fenólicos e a capacidade antioxidante de frutos de microtomateiro selvagem, cultivar "Micro-Tom" (MT, e seus mutantes fotomorfogenéticos high pigment 1 (hp1, super-responsivo a eventos mediados por luz e aurea (au, deficiente quantitativo em fitocromos. Vinte frutos maduros de cada genótipo (MT, hp1 e au foram utilizados para as análises, realizadas em triplicata. Para quantificação dos compostos fenólicos totais, foi utilizado o método de Folin-Ciocalteu e a capacidade antioxidante foi realizada pelos métodos Ferric Reducing Antioxidant Power (FRAP e 2,2-diphenyl-1-picrylhydrazyl (DPPH. Os frutos do mutante hp1 apresentaram maiores conteúdos de compostos fenólicos totais e também maior capacidade antioxidante em relação à cultivar selvagem ("MT" e ao mutante au, o qual não diferiu significativamente da cultivar "MT".

  14. La medición de la capacidad de resolución de problemas en las ciencias experimentales

    Directory of Open Access Journals (Sweden)

    José Joaquín García García

    2012-01-01

    Full Text Available Este trabajo presenta un estudio, sobre el diseño de una prueba para medir la capacidad de resolución de problemas utilizando la técnica de análisis factorial. La prueba presentó un alfa de Cronbach (α de 0,76 y 16 peguntas distribuidas en 7 factores ordenados de acuerdo al porcentaje en el cual explicaban la varianza de la capacidad: predicción y transferencia, capacidad de síntesis, lectura crítica del enunciado, análisis, interpretación de información, comprensión metacognitiva de enunciados y procesos, delimitación del problema. Así, la resolución de problemas es una capacidad que está más relacionada con factores de carácter estructural y global, como la selección de soluciones e hipótesis más adecuadas y la representación misma del problema, y en menor medida con aspectos estratégicos de delimitación, precisión y planeación, tal vez por la usual ausencia de dichos aspectos en las aulas de clase.

  15. La situación de las personas con capacidad intelectual límite en España

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    Agustín Huete García

    2016-06-01

    Full Text Available Se presentan los resultados principales de un estudio de carácter fundamentalmente descriptivo sobre la situación actual de las personas con capacidad intelectual límite en 2015. Se centra en describir la realidad demográfica y social de las personas con capacidad intelectual límite, sus necesidades de apoyo y extraer propuestas estratégicas hacia una inclusión social efectiva. Metodológicamente, de acuerdo al nivel de análisis, se optó por técnicas cuantitativas (análisis de fuentes estadísticas y cualitativas (entrevistas semiestructuradas a un grupo de personas con capacidad intelectual límite, familias y profesionales. Entre sus principales conclusiones, las personas con capacidad intelectual límite y sus familias demandan una visibilización de sus necesidades de apoyo para una inclusión social efectiva, siendo clave el apoyo para favorecer una vida autónoma e independiente. Las propuestas y buenas prácticas aportan elementos para un modelo de atención individualizada, al mismo tiempo fundamentada en una participación activa en la comunidad.

  16. Capacidades de fabricación y almacenaje óptimas en un sistema con logística inversa y demanda aleatoria

    OpenAIRE

    Benedito Benet, Ernest; Corominas Subias, Albert

    2009-01-01

    En el presente trabajo se estudia un sistema con demanda y retornos aleatorios para calcular las capacidades óptimas de fabricación y almacenaje. El modelo presentado permite estudiar el comportamiento de las capacidades de fabricación y almacenaje óptimas cuando varían los costes de producción.

  17. Acute exposure to lead increases myocardial contractility independent of hypertension development

    Energy Technology Data Exchange (ETDEWEB)

    Fioresi, M. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Departamento de Enfermagem, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Furieri, L.B.; Simões, M.R.; Ribeiro, R.F. Junior; Meira, E.F.; Fernandes, A.A.; Stefanon, I. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Vassallo, D.V. [Programa de Pós-Graduação em Ciências Fisiológicas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, ES (Brazil); Centro de Ciências da Saúde de Vitória, Escola Superior de Ciências da Santa Casa de Misericórdia de Vitória, Vitória, ES (Brazil)

    2013-02-01

    We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na{sup +},K{sup +}-ATPase and myosin Ca{sup 2+}-ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na{sup +},K{sup +}-ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension.

  18. Na+,K+-pump stimulation improves contractility in isolated muscles of mice with hyperkalemic periodic paralysis.

    Science.gov (United States)

    Clausen, Torben; Nielsen, Ole Bækgaard; Clausen, Johannes D; Pedersen, Thomas Holm; Hayward, Lawrence J

    2011-07-01

    In patients with hyperkalemic periodic paralysis (HyperKPP), attacks of muscle weakness or paralysis are triggered by K(+) ingestion or rest after exercise. Force can be restored by muscle work or treatment with β(2)-adrenoceptor agonists. A missense substitution corresponding to a mutation in the skeletal muscle voltage-gated Na(+) channel (Na(v)1.4, Met1592Val) causing human HyperKPP was targeted into the mouse SCN4A gene (mutants). In soleus muscles prepared from these mutant mice, twitch, tetanic force, and endurance were markedly reduced compared with soleus from wild type (WT), reflecting impaired excitability. In mutant soleus, contractility was considerably more sensitive than WT soleus to inhibition by elevated [K(+)](o). In resting mutant soleus, tetrodotoxin (TTX)-suppressible (22)Na uptake and [Na(+)](i) were increased by 470 and 58%, respectively, and membrane potential was depolarized (by 16 mV, P Na(+),K(+) pump-mediated (86)Rb uptake was 83% larger than in WT. Salbutamol stimulated (86)Rb uptake and reduced [Na(+)](i) both in mutant and WT soleus. Stimulating Na(+),K(+) pumps with salbutamol restored force in mutant soleus and extensor digitorum longus (EDL). Increasing [Na(+)](i) with monensin also restored force in soleus. In soleus, EDL, and tibialis anterior muscles of mutant mice, the content of Na(+),K(+) pumps was 28, 62, and 33% higher than in WT, respectively, possibly reflecting the stimulating effect of elevated [Na(+)](i) on the synthesis of Na(+),K(+) pumps. The results confirm that the functional disorders of skeletal muscles in HyperKPP are secondary to increased Na(+) influx and show that contractility can be restored by acute stimulation of the Na(+),K(+) pumps. Calcitonin gene-related peptide (CGRP) restored force in mutant soleus but caused no detectable increase in (86)Rb uptake. Repeated excitation and capsaicin also restored contractility, possibly because of the release of endogenous CGRP from nerve endings in the isolated

  19. Contractile function and motor unit firing rates of the human hamstrings.

    Science.gov (United States)

    Kirk, Eric A; Rice, Charles L

    2017-01-01

    Neuromuscular properties of the lower limb in health, aging, and disease are well described for major lower limb muscles comprising the quadriceps, triceps surae, and dorsiflexors, with the notable exception of the posterior thigh (hamstrings). The purpose of this study was to further characterize major muscles of the lower limb by comprehensively exploring contractile properties in relation to spinal motor neuron output expressed as motor unit firing rates (MUFRs) in the hamstrings of 11 (26.5 ± 3.8) young men. Maximal isometric voluntary contraction (MVC), voluntary activation, stimulated contractile properties including a force-frequency relationship, and MUFRs from submaximal to maximal voluntary contractile intensities were assessed in the hamstrings. Strength and MUFRs were assessed at two presumably different muscle lengths by varying the knee joint angles (90° and 160°). Knee flexion MVCs were 60-70% greater in the extended position (160°). The frequency required to elicit 50% of maximum tetanic torque was 16-17 Hz. Mean MUFRs at 25-50% MVC were 9-31% less in the biceps femoris compared with the semimembranosus-semitendinosus group. Knee joint angle (muscle length) influenced MUFRs such that mean MUFRs were greater in the shortened (90°) position at 50% and 100% MVC. Compared with previous reports, mean maximal MUFRs in the hamstrings are greater than those in the quadriceps and triceps surae and somewhat less than those in the tibialis anterior. Mean maximal MUFRs in the hamstrings are influenced by changes in knee joint angle, with lower firing rates in the biceps femoris compared with the semimembranosus-semitendinosus muscle group. We studied motor unit firing rates (MUFRs) at various voluntary contraction intensities in the hamstrings, one of the only major lower limb muscles to have MUFRs affected by muscle length changes. Within the hamstrings muscle-specific differences have greater impact on MUFRs than length changes, with the biceps femoris

  20. Muscle contractility decrement and correlated morphology during the pathogenesis of streptozotocin-diabetic mice.

    Science.gov (United States)

    Fahim, M A; el-Sabban, F; Davidson, N

    1998-06-01

    Peripheral neuropathy of both motor and sensory nerves has been well documented in diabetes mellitus, but the evidence for physiological and correlated morphological changes during the pathogenesis of myopathy is scarce. In the present report, we have chosen the dorsiflexor muscle of adult male mice as a model for studying in situ muscle contraction and neuromuscular ultrastructure during the pathogenesis of streptozotocin-induced diabetes. Thirty mice (30 g bodyweight) were injected once i.p. with streptozotocin solution (200 mg/Kg) to induce experimental diabetes mellitus. Comparative analyses of in situ muscle isometric contractile characteristics were studied (at 1 Hz, 5 Hz and 30 Hz nerve stimulation) in urethane-anesthetized (2 mg/g, i.p.) control and diabetic mice at three time points, 2 weeks, 4 weeks, and 8 weeks postinjection. Synaptic delay was also recorded in diabetic and age-matched control mice. There was a significant increase in synaptic delay in both 4-week and 8-week diabetic mice compared with control mice (8.9 +/- 1.2 msec and 7.6 +/- 0.6 msec, respectively, compared with 6.1 +/- 0.5 msec). At all three stimulation frequencies, diabetes did not affect muscle contractile speed but significantly reduced the twitch tension after 8 weeks, with no changes at 2 weeks or 4 weeks. The recorded single-twitch tension values were 2.6 +/- 0.3 g, 2.1 +/- 0.6 g, 2.2 +/- 0.7 g, and 1.2 +/- 0.1 g for control, 2 weeks, 4 weeks, and 8 weeks, respectively. At 30 Hz, the recorded tension values were 4.6 +/- 1.6 g, 3.1 +/- 1.2 g, 3.1 +/- 1.1 g, and 2.1 +/- 1.0 g for control, 2 weeks, 4 weeks, and 8 weeks, respectively. Ultrastructural changes in neuromuscular junctions were similar to those that have been described in disuse and aging. These changes were observed after 8 weeks and included serve loss of synaptic vesicles, electron-dense bodies, and myelin-like figures as well as degeneration of mitochondria. The results reveal that streptozotocin-induced diabetes

  1. Beta adrenergic overstimulation impaired vascular contractility via actin-cytoskeleton disorganization in rabbit cerebral artery.

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    Hyoung Kyu Kim

    Full Text Available BACKGROUND AND PURPOSE: Beta adrenergic overstimulation may increase the vascular damage and stroke. However, the underlying mechanisms of beta adrenergic overstimulation in cerebrovascular dysfunctions are not well known. We investigated the possible cerebrovascular dysfunction response to isoproterenol induced beta-adrenergic overstimulation (ISO in rabbit cerebral arteries (CAs. METHODS: ISO was induced in six weeks aged male New Zealand white rabbit (0.8-1.0 kg by 7-days isoproterenol injection (300 μg/kg/day. We investigated the alteration of protein expression in ISO treated CAs using 2DE proteomics and western blot analysis. Systemic properties of 2DE proteomics result were analyzed using bioinformatics software. ROS generation and following DNA damage were assessed to evaluate deteriorative effect of ISO on CAs. Intracellular Ca(2+ level change and vascular contractile response to vasoactive drug, angiotensin II (Ang II, were assessed to evaluate functional alteration of ISO treated CAs. Ang II-induced ROS generation was assessed to evaluated involvement of ROS generation in CA contractility. RESULTS: Proteomic analysis revealed remarkably decreased expression of cytoskeleton organizing proteins (e.g. actin related protein 1A and 2, α-actin, capping protein Z beta, and vimentin and anti-oxidative stress proteins (e.g. heat shock protein 9A and stress-induced-phosphoprotein 1 in ISO-CAs. As a cause of dysregulation of actin-cytoskeleton organization, we found decreased level of RhoA and ROCK1, which are major regulators of actin-cytoskeleton organization. As functional consequences of proteomic alteration, we found the decreased transient Ca(2+ efflux and constriction response to angiotensin II and high K(+ in ISO-CAs. ISO also increased basal ROS generation and induced oxidative damage in CA; however, it decreased the Ang II-induced ROS generation rate. These results indicate that ISO disrupted actin cytoskeleton proteome network

  2. La relación entre la capacidad de atencion dividida y la estimación prospectiva del tiempo

    Directory of Open Access Journals (Sweden)

    Susana Celeste Azzollini

    2004-01-01

    Full Text Available Se realizó una investigación cuyo objetivo fue determinar si la capacidad de atención dividida resultaba explicativa de la variabilidad de las estimaciones prospectivas del tiempo. Los modelos teóricos sobre dicha estimación postulan que los recursos atencionales de procesamiento están divididos entre un procesador temporal, que cuenta y almacena unidades temporales subjetivas (Subjective Temporal Units - STUs y otras actividades de procesamiento no temporal (Zakay, 1993. Se seleccionó una muestra de 36 estudiantes universitarios que fueron asignados al azar a cada una de las seis condiciones experimentales, determinadas por un diseño factorial 3 x 2, y sus factores básicos fueron: cantidad de tareas y niveles de complejidad del material. Se confeccionaron materiales para las diferentes tareas y otros con el fin de evaluar las aptitudes mnémicas y la capacidad de atención dividida. Se solicitó a los sujetos que mientras realizaban las tareas, detuvieran un cronómetro cuando consideraran que había pasado un período de tiempo predeterminado. La estimación del tiempo se calculó por la diferencia en segundos entre el tiempo real y el tiempo estimado. Los datos se procesaron con análisis de correlación, discriminante y factorial de variancia. Los resultados obtenidos indican que la capacidad de atención dividida se correlaciona con la estimación temporal prospectiva y además, la capacidad de atención dividida resulta un buen predictor de la capacidad estimativa de los sujetos, especialmente de los sobre-estimadores. Las diferencias en las aptitudes mnémicas no explicaron la variabilidad de las estimaciones prospectivas.

  3. Capacidad aeróbica, felicidad y satisfacción con la vida en adolescentes españoles

    Directory of Open Access Journals (Sweden)

    Juan A. Jim\\u00E9nez-Moral

    2013-01-01

    Full Text Available Objetivos: Analizar la asociación entre capacidad aeróbica, felicidad subjetiva y satisfacción con la vida en adolescentes. Método: Participaron 388 adolescentes (207 mujeres de 12-18 años de edad. La capacidad aeróbica se evaluó mediante el test de 20 metros de ida y vuelta. La felicidad subjetiva y la satisfacción con la vida se evaluaron mediante las escalas Subjective Happiness Scale y Satisfaction With Life Scale, respectivamente. Se midió el peso y la talla de los adolescentes y se calculó el índice de masa corporal (IMC. Los adolescentes indicaron el nivel de estudios de la madre. Resultados: Los análisis de regresión lineal mostraron que la capacidad aeróbica se asocia positivamente con felicidad subjetiva (ß no estandarizada = .09 ± .03, r = .128, p = .013 y satisfacción con la vida (ß no estandarizada = .31 ± .13, r = .118, p = .022, independientemente del sexo, IMC y estudios de la madre. Conclusión: Los resultados de este estudio sugieren que los adolescentes que tienen una mejor capacidad aeróbica también son más felices y tienen una mayor satisfacción con la vida. Hacen falta estudios de intervención para corroborar si un programa dirigido a la mejora de la capacidad aeróbica puede inducir también mejoras en los niveles de felicidad y satisfacción con la vida en adolescentes.

  4. Hysteroscopic sterilization with occlusion of sheep uterine tube using n-butyl-2-cyanoacrylate adhesive Esterilização histeroscópica com oclusão da tuba uterina de ovelha com adesivo de n-butil-2-cianoacrilato

    Directory of Open Access Journals (Sweden)

    Sergio Bigolin

    2007-10-01

    Full Text Available PURPOSE: To evaluate the fertility and analyze the macroscopic, microscopic and morphometric aspects of sheep uterine tube sterilization with a hysteroscopically insert of n-butyl-2-cyanoacrylate adhesive. METHODS: 12 adult sheep, with one previous pregnancy, were distributed as follows: group L (n=3 subjected to laparotomy and Pomeroy uterine tube ligation, group S (n=3 subjected to hysteroscopic application of saline solution in tube isthmus and group AD(n=6, that was subjected to hysteroscopic application of 0.5 ml of n-2-butil-cyanoacrylate in tube isthmus. They were mated with fertile males for ninety days. The non pregnant sheep, at the 90th day, were subjected to laparotomy with uterus and tubes uterine resection. The fragments of uterine tubes were fixated in 10% formalin and processes for histology evaluated, and slices dyes for H.E. Data were evaluated by Wilcoxon and Mann-Whitney and Fisher's exact test. RESULTS: All sheep from groups L and AD did not get pregnant (0% in contrast with sheep from group S (100%; the adhesive remained integral in the uterine tube lumen. The percentual of adherences (66.6% and fibrosis responses (100% was significantly higher in the group L than group AD (0% (pOBJETIVO: Avaliar a fertilidade e aspectos macroscópicos, microscópicos e morfométricos da esterilização histeroscópica de tubas uterinas de ovelhas com o adesivo de n-butil-2-cianoacrilato. MÉTODOS: 12 ovelhas adultas, com uma prenhez anterior, foram distribuídas como segue: o grupo L (n=3 submetidas à laparotomia e laqueadura tipo Pomeroy, grupo S (n=3 submetidas à aplicação histeroscópica de solução salina no istmo tubário e grupo AD (n=6, com aplicação histeroscópica de 0,5 ml de cianoacrilato. As ovelhas foram acasaladas com machos de comprovada fertilidade por noventa dias. As ovelhas não prenhes aos 90 dias, foram submetidas à laparotomia com ressecção do útero e tubas uterinas, que foram fixadas em formalina 10%s e os

  5. Fatores determinantes da capacidade funcional entre idosos Determinant factors of functional status among the elderly

    Directory of Open Access Journals (Sweden)

    Tereza Etsuko da Costa Rosa

    2003-02-01

    Full Text Available OBJETIVO; Investigar a influência de fatores socioeconômicos e demográficos relativos à saúde, bem como os fatores ligados às atividades sociais e à avaliação subjetiva da saúde sobre a capacidade funcional dos idosos. MÉTODOS: Estudo transversal, integrante de estudo multicêntrico, em amostra representativa do município de São Paulo, realizado em 1989. A capacidade funcional foi avaliada através da escala de atividades da vida diária pessoal e instrumental e investigada como variável dicotômica: ausência de dependência - incapacidade/dificuldade em nenhuma das atividades versus presença de dependência moderada/grave - incapacidade/dificuldade em 4 ou mais atividades. Análise de regressão logística múltipla foi aplicada aos fatores hierarquicamente agrupados. RESULTADOS: As características que se associaram com a dependência moderada/grave foram analfabetismo, ser aposentado, ser pensionista, ser dona de casa, não ser proprietário da moradia, ter mais de 65 anos, ter composição familiar multigeracional, ter sido internado nos últimos 6 meses, ser "caso" no rastreamento de saúde mental, não visitar amigos, ter problemas de visão, ter história de derrame, não visitar parentes e ter avaliação pessimista da saúde ao se comparar com seus pares. CONCLUSÕES: As características identificadas que se associaram à dependência moderada/grave sugerem uma complexa rede causal do declínio da capacidade funcional. Pode-se supor, entretanto, que ações preventivas especificamente voltadas para certos fatores podem propiciar benefícios para o prolongamento do bem estar da população idosa.OBJECTIVE: To investigate the impact of health-related demographic and socioeconomic factors, as well as the impact of factors associated to social activity and the subjective health evaluation on the functional status of elderly people. METHODS: A cross-sectional multicentric study was conducted in a representative population

  6. The Effect of Cleft Palate Repair on Contractile Properties of Single Permeabilized Muscle Fibers From Congenitally Cleft Goats Palates

    Science.gov (United States)

    A cleft palate goat model was used to study the contractile properties of the levator veli palatini (LVP) muscle which is responsible for the movement of the soft palate. In 15-25% of patients that undergo palatoplasty, residual velopharyngeal insufficiency (VPI) remains a problem and often require...

  7. Reduced Contractility and Motility of Prostatic Cancer-Associated Fibroblasts after Inhibition of Heat Shock Protein 90

    Directory of Open Access Journals (Sweden)

    Alex Henke

    2016-08-01

    Full Text Available Background: Prostate cancer-associated fibroblasts (CAF can stimulate malignant progression and invasion of prostatic tumour cells via several mechanisms including those active in extracellular matrix; Methods: We isolated CAF from prostate cancer patients of Gleason Score 6–10 and confirmed their cancer-promoting activity using an in vivo tumour reconstitution assay comprised of CAF and BPH1 cells. We tested the effects of heat shock protein 90 (HSP90 inhibitors upon reconstituted tumour growth in vivo. Additionally, CAF contractility was measured in a 3D collagen contraction assay and migration was measured by scratch assay; Results: HSP90 inhibitors dipalmitoyl-radicicol and 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG reduced tumour size and proliferation in CAF/BPH1 reconstituted tumours in vivo. We observed that the most contractile CAF were derived from patients with lower Gleason Score and of younger age compared with the least contractile CAF. HSP90 inhibitors radicicol and 17-DMAG inhibited contractility and reduced the migration of CAF in scratch assays. Intracellular levels of HSP70 and HSP90 were upregulated upon treatment with HSP90 inhibitors. Inhibition of HSP90 also led to a specific increase in transforming growth factor beta 2 (TGFβ2 levels in CAF; Conclusions: We suggest that HSP90 inhibitors act not only upon tumour cells, but also on CAF in the tumour microenvironment.

  8. Investigating Cardiac MRI Based Right Ventricular Contractility As A Novel Non-Invasive Metric of Pulmonary Arterial Pressure

    Science.gov (United States)

    Menon, Prahlad G; Adhypak, Srilakshmi M; Williams, Ronald B; Doyle, Mark; Biederman, Robert WW

    2014-01-01

    BACKGROUND We test the hypothesis that cardiac magnetic resonance (CMR) imaging-based indices of four-dimensional (4D) (three dimensions (3D) + time) right ventricle (RV) function have predictive values in ascertaining invasive pulmonary arterial systolic pressure (PASP) measurements from right heart catheterization (RHC) in patients with pulmonary arterial hypertension (PAH). METHODS We studied five patients with idiopathic PAH and two age and sex-matched controls for RV function using a novel contractility index (CI) for amplitude and phase to peak contraction established from analysis of regional shape variation in the RV endocardium over 20 cardiac phases, segmented from CMR images in multiple orientations. RESULTS The amplitude of RV contractility correlated inversely with RV ejection fraction (RVEF; R2 = 0.64, P = 0.03) and PASP (R2 = 0.71, P = 0.02). Phase of peak RV contractility also correlated inversely to RVEF (R2 = 0.499, P = 0.12) and PASP (R2 = 0.66, P = 0.04). CONCLUSIONS RV contractility analyzed from CMR offers promising non-invasive metrics for classification of PAH, which are congruent with invasive pressure measurements. PMID:25624777

  9. 5-HT4 receptors mediating enhancement of contractility in canine stomach; an in vitro and in vivo study

    NARCIS (Netherlands)

    Prins, NH; van der Grijn, A; Lefebvre, RA; Akkermans, LMA; Schuurkes, JAJ

    1 We aimed to study 5-HT4 receptors in canine stomach contractility both in vivo and in vitro. 2 In anaesthetized Beagle dogs, the selective 5-HT4 receptor agonist prucalopride (i.v.) induced dose-dependent tonic stomach contractions under isobaric conditions, an effect that was antagonized by the

  10. Inhibition of MMP-2 Expression with siRNA Increases Baseline Cardiomyocyte Contractility and Protects against Simulated Ischemic Reperfusion Injury

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    Han-Bin Lin

    2014-01-01

    Full Text Available Matrix metalloproteinases (MMPs significantly contribute to ischemia reperfusion (I/R injury, namely, by the degradation of contractile proteins. However, due to the experimental models adopted and lack of isoform specificity of MMP inhibitors, the cellular source and identity of the MMP(s involved in I/R injury remain to be elucidated. Using isolated adult rat cardiomyocytes, subjected to chemically induced I/R-like injury, we show that specific inhibition of MMP-2 expression and activity using MMP-2 siRNA significantly protected cardiomyocyte contractility from I/R-like injury. This was also associated with increased expression of myosin light chains 1 and 2 (MLC1/2 in comparison to scramble siRNA transfection. Moreover, the positive effect of MMP-2 siRNA transfection on cardiomyocyte contractility and MLC1/2 expression levels was also observed under control conditions, suggesting an important additional role for MMP-2 in physiological sarcomeric protein turnover. This study clearly demonstrates that intracellular expression of MMP-2 plays a significant role in sarcomeric protein turnover, such as MLC1 and MLC2, under aerobic (physiological conditions. In addition, this study identifies intracellular/autocrine, cardiomyocyte-produced MMP-2, rather than paracrine/extracellular, as responsible for the degradation of MLC1/2 and consequent contractile dysfunction in cardiomyocytes subjected to I/R injury.

  11. Effect of Propafenone on the Contractile Activity of Latissimus Dorsi Muscle Isolated in an Organ Chamber: Experimental Study in Rats

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    Ricardo Simões

    2002-03-01

    Full Text Available OBJECTIVE: To study the effect of propafenone on the contractile function of latissimus dorsi muscle isolated from rats in an organ chamber. METHODS: We studied 20 latissimus dorsi muscles of Wistar rats and divided them into 2 groups: group I (n=10, or control group - we studied the feasibility of muscle contractility; group II (n=10, in which the contralateral muscles were grouped - we analyzed the effect of propafenone on muscle contractility. After building a muscle ring, 8 periods of sequential 2-minute baths were performed, with intervals of preprogrammed electrical stimulation using a pacemaker of 50 stimuli/min. In group II, propafenone, at the concentration of 9.8 µg/mL, was added to the bath in period 2 and withdrawn in period 4. RESULTS: In group I, no significant depression in muscle contraction occurred up to period 5 (p>0.05. In group II, a significant depression occurred in all periods, except between the last 2 periods (p0.05. CONCLUSION: Propafenone had a depressing effect on the contractile function of latissimus dorsi muscle isolated from rats and studied in an organ chamber.

  12. Effect of acute and chronic simvastatin treatment on post-ischemic contractile dysfunction in isolated rat heart

    Czech Academy of Sciences Publication Activity Database

    Szárszoi, Ondrej; Malý, J.; Ošťádal, P.; Netuka, I.; Bešík, J.; Kolář, František; Ošťádal, Bohuslav

    2008-01-01

    Roč. 57, č. 5 (2008), s. 793-796 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 1M0510 Institutional research plan: CEZ:AV0Z50110509 Keywords : simvastatin * contractile dysfunction * protection Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.653, year: 2008

  13. [A basis for application of cardiac contractility variability in the Evaluation and assessment of exercise and fitness].

    Science.gov (United States)

    Bu, Bin; Wang, Aihua; Han, Haijun; Xiao, Shouzhong

    2010-06-01

    Cardiac contractility variability (CCV) is a new concept which is introduced in the research field of cardiac contractility in recent years, that is to say, there are some disparities between cardiac contractilities when heart contracts. The changing signals of cardiac contractility contain a plenty of information on the cardiovascular function and disorder. In order to collect and analyze the message, we could quantitatively evaluate the tonicity and equilibrium of cardiac sympathetic nerve and parasympathetic nerve, and the effects of bio-molecular mechanism on the cardiovascular activities. By analyzing CCV, we could further understand the background of human being's heritage characteristics, nerve types, the adjusting mechanism, the molecular biology, and the adjustment of cardiac automatic nerve. With the development of the computing techniques, the digital signal processing method and its application in medical field, this analysis has been progressing greatly. By now, the assessment of CCV, just like the analysis of heart rate variability, is mainly via time domain and frequency domain analysis. CCV is one of the latest research fields in human cardiac signals being scarcely reported in the field of sports medicine; however, its research progresses are of important value for cardiac physiology and pathology in sports medicine and rehabilitation medicine.

  14. Effects of testosterone on contractile properties of sexually dimorphic forelimb muscles in male bullfrogs (Rana catesbeiana, Shaw 1802

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    Aaron R. Kampe

    2013-07-01

    This study examined the effects of testosterone (T on the contractile properties of two sexually dimorphic forelimb muscles and one non-dimorphic muscle in male bullfrogs (Rana catesbeiana, Shaw 1802. The dimorphic muscles in castrated males with testosterone replacement (T+ achieved higher forces and lower fatigability than did castrated males without replaced testosterone (T0 males, but the magnitude of the differences was low and many of the pair-wise comparisons of each muscle property were not statistically significant. However, when taken as a whole, the means of seven contractile properties varied in the directions expected of masculine values in T+ animals in the sexually dimorphic muscles. Moreover, these data, compared with previous data on male and female bullfrogs, show that values for T+ males are similar to normal males and are significantly different from females. The T0 males tended to be intermediate in character between T+ males and females, generally retaining masculine values. This suggests that the exposure of young males to T in their first breeding season produces a masculinizing effect on the sexually dimorphic muscles that is not reversed between breeding seasons when T levels are low. The relatively minor differences in contractile properties between T+ and T0 males may indicate that as circulating T levels rise during breeding season in normal males, contractile properties can be enhanced rapidly to maximal functional levels for breeding success.

  15. Microtubule depolymerization normalizes in vivo myocardial contractile function in dogs with pressure-overload left ventricular hypertrophy

    Science.gov (United States)

    Koide, M.; Hamawaki, M.; Narishige, T.; Sato, H.; Nemoto, S.; DeFreyte, G.; Zile, M. R.; Cooper G, I. V.; Carabello, B. A.

    2000-01-01

    BACKGROUND: Because initially compensatory myocardial hypertrophy in response to pressure overloading may eventually decompensate to myocardial failure, mechanisms responsible for this transition have long been sought. One such mechanism established in vitro is densification of the cellular microtubule network, which imposes a viscous load that inhibits cardiocyte contraction. METHODS AND RESULTS: In the present study, we extended this in vitro finding to the in vivo level and tested the hypothesis that this cytoskeletal abnormality is important in the in vivo contractile dysfunction that occurs in experimental aortic stenosis in the adult dog. In 8 dogs in which gradual stenosis of the ascending aorta had caused severe left ventricular (LV) pressure overloading (gradient, 152+/-16 mm Hg) with contractile dysfunction, LV function was measured at baseline and 1 hour after the intravenous administration of colchicine. Cardiocytes obtained by biopsy before and after in vivo colchicine administration were examined in tandem. Microtubule depolymerization restored LV contractile function both in vivo and in vitro. CONCLUSIONS: These and additional corroborative data show that increased cardiocyte microtubule network density is an important mechanism for the ventricular contractile dysfunction that develops in large mammals with adult-onset pressure-overload-induced cardiac hypertrophy.

  16. Effect of a Periodized Power Training Program on the Functional Performances and Contractile Properties of the Quadriceps in Sprinters

    Science.gov (United States)

    Kamandulis, Sigitas; Skurvydas, Albertas; Brazaitis, Marius; Stanislovaitis, Aleksas; Duchateau, Jacques; Stanislovaitiene, Jurate

    2012-01-01

    Our purpose was to compare the effect of a periodized preparation consisting of power endurance training and high-intensity power training on the contractile properties of the quadriceps muscle and functional performances in well trained male sprinters (n = 7). After 4 weeks of high-intensity power training, 60-m sprint running time improved by an…

  17. Alterations in serotonin receptor-induced contractility of bovine lateral saphenous vein in cattle grazing endophyte-infected tall fescue

    Science.gov (United States)

    As part of a large 2-year study documenting the physiologic impact of grazing endophyte-infected tall fescue on growing cattle, 2 experiments were conducted to characterize and evaluate the effects of grazing 2 levels of toxic endophyte-infected tall fescue pastures on vascular contractility and ser...

  18. Bidirectional Interplay between Vimentin Intermediate Filaments and Contractile Actin Stress Fibers

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    Yaming Jiu

    2015-06-01

    Full Text Available The actin cytoskeleton and cytoplasmic intermediate filaments contribute to cell migration and morphogenesis, but the interplay between these two central cytoskeletal elements has remained elusive. Here, we find that specific actin stress fiber structures, transverse arcs, interact with vimentin intermediate filaments and promote their retrograde flow. Consequently, myosin-II-containing arcs are important for perinuclear localization of the vimentin network in cells. The vimentin network reciprocally restricts retrograde movement of arcs and hence controls the width of flat lamellum at the leading edge of the cell. Depletion of plectin recapitulates the vimentin organization phenotype of arc-deficient cells without affecting the integrity of vimentin filaments or stress fibers, demonstrating that this cytoskeletal cross-linker is required for productive interactions between vimentin and arcs. Collectively, our results reveal that plectin-mediated interplay between contractile actomyosin arcs and vimentin intermediate filaments controls the localization and dynamics of these two cytoskeletal systems and is consequently important for cell morphogenesis.

  19. Transcellular tunnel dynamics: Control of cellular dewetting by actomyosin contractility and I-BAR proteins.

    Science.gov (United States)

    Lemichez, Emmanuel; Gonzalez-Rodriguez, David; Bassereau, Patricia; Brochard-Wyart, Françoise

    2013-03-01

    Dewetting is the spontaneous withdrawal of a liquid film from a non-wettable surface by nucleation and growth of dry patches. Two recent reports now propose that the principles of dewetting explain the physical phenomena underpinning the opening of transendothelial cell macroaperture (TEM) tunnels, referred to as cellular dewetting. This was discovered by studying a group of bacterial toxins endowed with the property of corrupting actomyosin cytoskeleton contractility. For both liquid and cellular dewetting, the growth of holes is governed by a competition between surface forces and line tension. We also discuss how the dynamics of TEM opening and closure represent remarkable systems to investigate actin cytoskeleton regulation by sensors of plasma membrane curvature and investigate the impact on membrane tension and the role of TEM in vascular dysfunctions. Copyright © 2013 Soçiété Française des Microscopies and Soçiété de Biologie Cellulaire de France.

  20. Nonequilibrium phase transitions, fluctuations and correlations in an active contractile polar fluid.

    Science.gov (United States)

    Gowrishankar, Kripa; Rao, Madan

    2016-02-21

    We study the patterning, fluctuations and correlations of an active polar fluid consisting of contractile polar filaments on a two-dimensional substrate, using a hydrodynamic description. The steady states generically consist of arrays of inward pointing asters and show a continuous transition from a moving lamellar phase, a moving aster street, to a stationary aster lattice with no net polar order. We next study the effect of spatio-temporal athermal noise, parametrized by an active temperature TA, on the stability of the ordered phases. In contrast to its equilibrium counterpart, we find that the active crystal shows true long range order at low TA. On increasing TA, the asters dynamically remodel, concomitantly we find novel phase transitions characterized by bond-orientational and polar order upon "heating".

  1. Image Processing Techniques for Assessing Contractility in Isolated Adult Cardiac Myocytes

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    Carlos Bazan

    2009-01-01

    The physiologic application of the methodology is evaluated by assessing overall contraction in enzymatically dissociated adult rat cardiocytes. Our results demonstrate the effectiveness of the proposed approach in characterizing the true, two-dimensional, “shortening” in the contraction process of adult cardiocytes. We compare the performance of the proposed method to that of a popular edge detection system in the literature. The proposed method not only provides a more comprehensive assessment of the myocyte contraction process but also can potentially eliminate historical concerns and sources of errors caused by myocyte rotation or translation during contraction. Furthermore, the versatility of the image processing techniques makes the method suitable for determining myocyte shortening in cells that usually bend or move during contraction. The proposed method can be utilized to evaluate changes in contractile behavior resulting from drug intervention, disease modeling, transgeneity, or other common applications to mammalian cardiocytes.

  2. A new strain gage method for measuring the contractile strain ratio of Zircaloy tubing

    International Nuclear Information System (INIS)

    Hwang, S.K.; Sabol, G.P.

    1988-01-01

    An improved strain gage method for determining the contractile strain ratio (CSR) of Zircaloy tubing was developed. The new method consists of a number of load-unload cyclings at approximately 0.2% plastic strain interval. With this method the CSR of Zircaloy-4 tubing could be determined accurately because it was possible to separate the plastic strains from the elastic strain involvement. The CSR values determined by use of the new method were in good agreement with those calculated from conventional post-test manual measurements. The CSR of the tubing was found to decrease with the amount of deformation during testing because of uneven plastic flow in the gage section. A new technique of inscribing gage marks by use of a YAG laser is discussed. (orig.)

  3. La arquitectura organizacional y las capacidades estratégicas empresariales empresariales

    Directory of Open Access Journals (Sweden)

    Jesús Perdomo-Ortiz

    2016-05-01

    Full Text Available El diseño organizacional y la teoría basada en los recursos han sido las dos áreas de la economía de la empresa que más desarrollo e impacto en la gerencia, y en el estado del arte de la disciplina, han tenido durante los últimos 15 años. Este documento aborda desde una perspectiva comparada ambos temas y encuentra una estrecha relación de mutuo apoyo conceptual. Es importante precisar que el presente documento no es una revisión de la literatura sobre diseño o arquitectura organizacional; no obstante se soporta en un conjunto de lecturas centradas en dicha temática. En este sentido, el objetivo del documento es hacer una reflexión crítica, planteando unas hipótesis de trabajo y argumentando su elaboración. La literatura sobre dirección estratégica tiene como uno de sus soportes disciplinares la denominada teoría (visión de la empresa basada en los recursos (The Resource-Based View of the Firm, RBV y defiende una lógica implícita de causalidad, al considerar la estructura organizacional como una consecuencia de la estrategia empresarial. Una visión crítica de la arquitectura organizacional contrasta la causalidad estrategia → estructura y puede explicar un vacío en la RBV, cuando ésta trata de explicar el tránsito del concepto de recurso a capacidad, haciendo alusión a un necesario proceso de integración de recursos básicos. Este documento plantea, entonces, la hipótesis de que la arquitectura organizacional es una forma de explicar la conformación de capacidades empresariales y, desde su argumentación, muestra cómo la causalidad → estrategia estructura se puede entender en forma inversa.

  4. INFLUÊNCIA DO TIRO COM ZARABATANA NA CAPACIDADE RESPIRATÓRIA DO IDOSO

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    Catarina Leitão

    2015-05-01

    Full Text Available A  respiração é um processo vital e faz parte das funções primordiais do corpo humano. A falta de consciência respiratória é responsável por diversos problemas o que leva a que com o passar do tempo, a respiração, possa provocar não só deformidades no tórax como também modificações posturais, incapacidade funcional e diversas patologias (Tribastone, 2001.O sistema respiratório é o sistema do organismo que envelhece mais rápido devido à exposição aos poluentes ambientais ao longo da vida. A nível clínico ocorrem mudanças relevantes que se traduzem na deterioração da função pulmonar. Calculando-se que em Portugal, as doenças respiratórias a curto prazo sejam a terceira causa de morte e afetem maioritariamente as pessoas idosas (Ruivo et al., 2009. No processo respiratório são essenciais dois tempos, a inspiração e expiração, que resultam de movimentos respiratórios nos quais o diafragma e os pulmões exercem funções fundamentais (Parreiral, 2005. Acreditamos que o tiro com zarabatana, que trabalha a expiração- através da expulsão enérgica de dardos e a inspiração- aquando do início do treino, poderá ser benéfico para a capacidade respiratória dos idosos. Objetivo: O presente estudo visa avaliar os efeitos da prática de Tiro com Zarabatana, na capacidade respiratória de pessoas idosas, mais precisamente as alterações ao nível do débito expiratório máximo.

  5. CAPACIDAD ANTIOXIDANTE Y CALIDAD POST-DESCONGELACIÓN DEL SEMEN EQUINO CRIOPRESERVADO CON QUERCETINA Y ERGOTIONEINA

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    G. Restrepo

    2016-01-01

    Full Text Available Se evaluó la capacidad antioxidante y la calidad post-descongelación del semen equinocriopreservado con quercetina y ergotioneina. Nueve eyaculados provenientes de trescaballos criollos colombianos se criopreservaron bajo tres tratamientos: ergotioneina (100μM, quercetina (100 μM y control (sin antioxidante. Posteriormente a la descongelaciónse evaluaron los siguientes parámetros: la capacidad antioxidante total (CAT delsemen mediante el ensayo del ácido 2,2´-azino-bis-[3-etilbenzotiazolina]-6-sulfónico(ABTS•+; la movilid ad total (MT; la movilidad progresiva (MP; la hiperactividad(HA y las velocidades curvilínea (VCL, lineal (VSL y media (VA P mediante el sistemacomputarizado SCA®; además, la integridad estructural de la membrana y la integridadacrosómica por microscopia de fluorescencia mediante las sondas SYBR/IP y FITC/PNA , respectivamente; la morfología mediante la tinción eosina-nigrosina y la integridadfuncional de membrana a través de la prueba hipoosmótica (HOS. Se realizó el ajustede modelos lineales generalizados (GLM y la comparación de medias por Tukey. LaCAT (μmol trolox/ml del semen descongelado fue superior para la ergotioneina (4,0 ±0,3 y la quercetina (3,9 ± 0,4, respecto del control (2,6 ± 1,5. Para la MT se encontróuna media superior para la ergotioneina (70,3 ± 11,2 %, respecto a la quercetina (63± 10,5 % y al control (66,1 ± 11,2 % (P < 0,05. Para MP, HA, VCL, VSL y VA P, eltratamiento control presentó valores superiores a los tratamientos con antioxidantes (P< 0,05. Se concluye que la ergotioneina y la quercetina incrementan la CAT e influyensobre la movilidad y la cinética post-descongelación del semen equino.

  6. POTÊNCIA E CAPACIDADE ANAERÓBIA EM ATLETAS DE KARATE

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    Keith Sato Urbinati

    2011-01-01

    Full Text Available O objetivo do presente estudo foi verificar o nível de potência muscular, bem como a intensidade de esforço durante prova de potência e capacidade anaeróbia em atletas de Karate. Participaram do estudo treze karatekas especialistas em prova de kumitê (luta,sexo masculino, idade média de 20,7±3,79 anos. Realizou-se a avaliação de potência e capacidade anaeróbia (Wingate test, com coleta das variáveis fisiológicas:frequência cardíaca (FC, pressão arterial (PA e lactato sanguíneo (LAC de repouso, imediatamente após e em 5 min de recuperação. Para verificar se ocorrem diferenças nas variáveis fisiológicas durante o teste, realizou-se análise de variância, post hoc de Bonferronie (p?0,05. Verificou-se potência de pico(PP de 8,77 ± 0,99 W/kg-1, potência média (PM de 5,13± 0,49 W.kg-1 e % de fadiga de 50,5 ± 6,45%. Para as variáveis fisiológicas,a FC (F=9,79; p=0,00 pós-teste de Wingate foi estatisticamente maior e diferenteda FC de repouso e recuperação. Não foram encontradas diferenças nos níveis pressatórios e nas concentrações de LAC. Em relação aos valores de FC e LAC tais variáveis pós-teste não se apresentaram elevados. Os valores de potência anaeróbia estão de acordo com a necessidade da modalidade esportiva. Assim, verificou-se menores intensidades de esforço em teste de Wingate quando comparados a de situação real de competição. O nível de potência muscular parece estar adequado ao kumitê.

  7. Leucine elicits myotube hypertrophy and enhances maximal contractile force in tissue engineered skeletal muscle in vitro.

    Science.gov (United States)

    Martin, Neil R W; Turner, Mark C; Farrington, Robert; Player, Darren J; Lewis, Mark P

    2017-10-01

    The amino acid leucine is thought to be important for skeletal muscle growth by virtue of its ability to acutely activate mTORC1 and enhance muscle protein synthesis, yet little data exist regarding its impact on skeletal muscle size and its ability to produce force. We utilized a tissue engineering approach in order to test whether supplementing culture medium with leucine could enhance mTORC1 signaling, myotube growth, and muscle function. Phosphorylation of the mTORC1 target proteins 4EBP-1 and rpS6 and myotube hypertrophy appeared to occur in a dose dependent manner, with 5 and 20 mM of leucine inducing similar effects, which were greater than those seen with 1 mM. Maximal contractile force was also elevated with leucine supplementation; however, although this did not appear to be enhanced with increasing leucine doses, this effect was completely ablated by co-incubation with the mTOR inhibitor rapamycin, showing that the augmented force production in the presence of leucine was mTOR sensitive. Finally, by using electrical stimulation to induce chronic (24 hr) contraction of engineered skeletal muscle constructs, we were able to show that the effects of leucine and muscle contraction are additive, since the two stimuli had cumulative effects on maximal contractile force production. These results extend our current knowledge of the efficacy of leucine as an anabolic nutritional aid showing for the first time that leucine supplementation may augment skeletal muscle functional capacity, and furthermore validates the use of engineered skeletal muscle for highly-controlled investigations into nutritional regulation of muscle physiology. © 2017 The Authors. Journal of Cellular Physiology Published by wiley periodicals, Inc.

  8. Exposure to low mercury concentration in vivo impairs myocardial contractile function

    International Nuclear Information System (INIS)

    Furieri, Lorena Barros; Fioresi, Mirian; Junior, Rogerio Faustino Ribeiro; Bartolome, Maria Visitacion; Fernandes, Aurelia Araujo; Cachofeiro, Victoria; Lahera, Vicente; Salaices, Mercedes; Stefanon, Ivanita; Vassallo, Dalton Valentim

    2011-01-01

    Increased cardiovascular risk after mercury exposure has been described but cardiac effects resulting from controlled chronic treatment are not yet well explored. We analyzed the effects of chronic exposure to low mercury concentrations on hemodynamic and ventricular function of isolated hearts. Wistar rats were treated with HgCl 2 (1st dose 4.6 μg/kg, subsequent dose 0.07 μg/kg/day, im, 30 days) or vehicle. Mercury treatment did not affect blood pressure (BP) nor produced cardiac hypertrophy or changes of myocyte morphometry and collagen content. This treatment: 1) in vivo increased left ventricle end diastolic pressure (LVEDP) without changing left ventricular systolic pressure (LVSP) and heart rate; 2) in isolated hearts reduced LV isovolumic systolic pressure and time derivatives, and β-adrenergic response; 3) increased myosin ATPase activity; 4) reduced Na + -K + ATPase (NKA) activity; 5) reduced protein expression of SERCA and phosphorylated phospholamban on serine 16 while phospholamban expression increased; as a consequence SERCA/phospholamban ratio reduced; 6) reduced sodium/calcium exchanger (NCX) protein expression and α-1 isoform of NKA, whereas α-2 isoform of NKA did not change. Chronic exposure for 30 days to low concentrations of mercury does not change BP, heart rate or LVSP but produces small but significant increase of LVEDP. However, in isolated hearts mercury treatment promoted contractility dysfunction as a result of the decreased NKA activity, reduction of NCX and SERCA and increased PLB protein expression. These findings offer further evidence that mercury chronic exposure, even at small concentrations, is an environmental risk factor affecting heart function. - Highlights: → Unchanges blood pressure, heart rate, systolic pressure. → Increases end diastolic pressure. → Promotes cardiac contractility dysfunction. → Decreases NKA activity, NCX and SERCA, increases PLB protein expression. → Small concentrations constitutes

  9. Tension cost correlates with mechanical and biochemical parameters in different myocardial contractility conditions

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    Cleci M. Moreira

    2012-01-01

    Full Text Available OBJECTIVES: Tension cost, the ratio of myosin ATPase activity to tension, reflects the economy of tension development in the myocardium. To evaluate the mechanical advantage represented by the tension cost, we studied papillary muscle contractility and the activity of myosin ATPase in the left ventricles in normal and pathophysiological conditions. METHODS: Experimental protocols were performed using rat left ventricles from: (1 streptozotocin-induced diabetic and control Wistar rats; (2 N-nitro-L-arginine methyl ester (L-NAME hypertensive and untreated Wistar rats; (3 deoxycorticosterone acetate (DOCA salt-treated, nephrectomized and salt- and DOCA-treated rats; (4 spontaneous hypertensive rats (SHR and Wistar Kyoto (WKY rats; (5 rats with myocardial infarction and shamoperated rats. The isometric force, tetanic tension, and the activity of myosin ATPase were measured. RESULTS: The results obtained from infarcted, diabetic, and deoxycorticosterone acetate-salt-treated rats showed reductions in twitch and tetanic tension compared to the control and sham-operated groups. Twitch and tetanic tension increased in the N-nitro-L-arginine methyl ester-treated rats compared with the Wistar rats. Myosin ATPase activity was depressed in the infarcted, diabetic, and deoxycorticosterone acetate salt-treated rats compared with control and sham-operated rats and was increased in N-nitro-L-arginine methyl ester-treated rats. These parameters did not differ between SHR and WKY rats. In the studied conditions (e.g., post-myocardial infarction, deoxycorticosterone acetate salt-induced hypertension, chronic N-nitro-L-arginine methyl ester treatment, and streptozotocin-induced diabetes, a positive correlation between force or plateau tetanic tension and myosin ATPase activity was observed. CONCLUSION: Our results suggest that the myocardium adapts to force generation by increasing or reducing the tension cost to maintain myocardial contractility with a better

  10. Perfusion-induced changes in cardiac contractility depend on capillary perfusion.

    Science.gov (United States)

    Dijkman, M A; Heslinga, J W; Sipkema, P; Westerhof, N

    1998-02-01

    The perfusion-induced increase in cardiac contractility (Gregg phenomenon) is especially found in heart preparations that lack adequate coronary autoregulation and thus protection of changes in capillary pressure. We determined in the isolated perfused papillary muscle of the rat whether cardiac muscle contractility is related to capillary perfusion. Oxygen availability of this muscle is independent of internal perfusion, and perfusion may be varied or even stopped without loss of function. Muscles contracted isometrically at 27 degrees C (n = 7). During the control state stepwise increases in perfusion pressure resulted in all muscles in a significant increase in active tension. Muscle diameter always increased with increased perfusion pressure, but muscle segment length was unaffected. Capillary perfusion was then obstructed by plastic microspheres (15 microns). Flow, at a perfusion pressure of 66.6 +/- 26.2 cmH2O, reduced from 17.6 +/- 5.4 microliters/min in the control state to 3.2 +/- 1.3 microliters/min after microspheres. Active tension developed by the muscle in the unperfused condition before microspheres and after microspheres did not differ significantly (-12.8 +/- 29.4% change). After microspheres similar perfusion pressure steps as in control never resulted in an increase in active tension. Even at the two highest perfusion pressures (89.1 +/- 28.4 and 106.5 +/- 31.7 cmH2O) that were applied a significant decrease in active tension was found. We conclude that the Gregg phenomenon is related to capillary perfusion.

  11. Troglitazone stimulates β-arrestin-dependent cardiomyocyte contractility via the angiotensin II type 1A receptor

    International Nuclear Information System (INIS)

    Tilley, Douglas G.; Nguyen, Anny D.; Rockman, Howard A.

    2010-01-01

    Peroxisome proliferator-activated receptor γ (PPARγ) agonists are commonly used to treat cardiovascular diseases, and are reported to have several effects on cardiovascular function that may be due to PPARγ-independent signaling events. Select angiotensin receptor blockers (ARBs) interact with and modulate PPARγ activity, thus we hypothesized that a PPARγ agonist may exert physiologic effects via the angiotensin II type 1 A receptor (AT1 A R). In AT1 A R-overexpressing HEK 293 cells, both angiotensin II (Ang II) and the PPARγ agonist troglitazone (Trog) enhanced AT1 A R internalization and recruitment of endogenous β-arrestin1/2 (βarr1/2) to the AT1 A R. A fluorescence assay to measure diacylglycerol (DAG) accumulation showed that although Ang II induced AT1 A R-G q protein-mediated DAG accumulation, Trog had no impact on DAG generation. Trog-mediated recruitment of βarr1/2 was selective to AT1 A R as the response was prevented by an ARB- and Trog-mediated βarr1/2 recruitment to β1-adrenergic receptor (β1AR) was not observed. In isolated mouse cardiomyocytes, Trog increased both % and rate of cell shortening to a similar extent as Ang II, effects which were blocked with an ARB. Additionally, these effects were found to be βarr2-dependent, as cardiomyocytes isolated from βarr2-KO mice showed blunted contractile responses to Trog. These findings show for the first time that the PPARγ agonist Trog acts at the AT1 A R to simultaneously block G q protein activation and induce the recruitment of βarr1/2, which leads to an increase in cardiomyocyte contractility.

  12. Pentamidine rescues contractility and rhythmicity in a Drosophila model of myotonic dystrophy heart dysfunction

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    Mouli Chakraborty

    2015-12-01

    Full Text Available Up to 80% of individuals with myotonic dystrophy type 1 (DM1 will develop cardiac abnormalities at some point during the progression of their disease, the most common of which is heart blockage of varying degrees. Such blockage is characterized by conduction defects and supraventricular and ventricular tachycardia, and carries a high risk of sudden cardiac death. Despite its importance, very few animal model studies have focused on the heart dysfunction in DM1. Here, we describe the characterization of the heart phenotype in a Drosophila model expressing pure expanded CUG repeats under the control of the cardiomyocyte-specific driver GMH5-Gal4. Morphologically, expression of 250 CUG repeats caused abnormalities in the parallel alignment of the spiral myofibrils in dissected fly hearts, as revealed by phalloidin staining. Moreover, combined immunofluorescence and in situ hybridization of Muscleblind and CUG repeats, respectively, confirmed detectable ribonuclear foci and Muscleblind sequestration, characteristic features of DM1, exclusively in flies expressing the expanded CTG repeats. Similarly to what has been reported in humans with DM1, heart-specific expression of toxic RNA resulted in reduced survival, increased arrhythmia, altered diastolic and systolic function, reduced heart tube diameters and reduced contractility in the model flies. As a proof of concept that the fly heart model can be used for in vivo testing of promising therapeutic compounds, we fed flies with pentamidine, a compound previously described to improve DM1 phenotypes. Pentamidine not only released Muscleblind from the CUG RNA repeats and reduced ribonuclear formation in the Drosophila heart, but also rescued heart arrhythmicity and contractility, and improved fly survival in animals expressing 250 CUG repeats.

  13. Low thermal dependence of the contractile properties of a wing muscle in the bat Carollia perspicillata.

    Science.gov (United States)

    Rummel, Andrea D; Swartz, Sharon M; Marsh, Richard L

    2018-05-29

    Temperature affects contractile rate properties in muscle, which may affect locomotor performance. Endotherms are known to maintain high core body temperatures, but temperatures in the periphery of the body can fluctuate. Such a phenomenon occurs in bats, whose wing musculature is relatively poorly insulated, resulting in substantially depressed temperatures in the distal wing. We examined a wing muscle in the small-bodied tropical bat Carollia perspicillata and a hindlimb muscle in the laboratory mouse at 5°C intervals from 22 to 42°C to determine the thermal dependence of the contractile properties of both muscles. We found that the bat ECRL had low thermal dependence from near body temperature to 10°C lower, with Q 10 values of less than 1.5 for relaxation from contraction and shortening velocities in that interval, and with no significant difference in some rate properties in the interval between 32 and 37°C. In contrast, for all temperature intervals below 37°C, Q 10 values for the mouse EDL were 1.5 or higher, and rate properties differed significantly across successive temperature intervals from 37 to 22°C. An ANCOVA analysis found that the thermal dependencies of all measured isometric and isotonic rate processes were significantly different between the bat and mouse muscles. The relatively low thermal dependence of the bat muscle likely represents a downward shift of its optimal temperature and may be functionally significant in light of the variable operating temperatures of bat wing muscles. © 2018. Published by The Company of Biologists Ltd.

  14. A comparison of the contractile properties of smooth muscle from pig urethra and internal anal sphincter.

    Science.gov (United States)

    Ramalingam, Thanesan; Durlu-Kandilci, N Tugba; Brading, Alison F

    2010-09-01

    Smooth muscles from the urethra and internal anal sphincter (IAS) play an essential role in the maintenance of urinary and fecal continence. Any damage in these muscles may cause serious problems. The aim of this study was to directly compare the contractile properties of pig urethra and IAS taken from the same animal. Smooth muscle strips of urethra and IAS dissected from the same pig were transferred to organ baths superfused with Krebs' solution, loaded with 1 g tension and equilibrated for 1 hr. Carbachol and phenylephrine response curves and EFS responses were elicited in the absence and presence of inhibitors. Both tissues developed tone during the 1 hr equilibration period. Carbachol (3 × 10(-6)-10(-3) M) contracted urethra whilst relaxing IAS. Guanethidine (10(-6) M) inhibited the carbachol responses in both tissues. L-NOARG (10(-4) M) decreased carbachol responses in IAS, but not in urethra. Phenylephrine (3 × 10(-6)-10(-2) M) contracted both tissues. EFS (1-40 Hz) induced a contractile response in urethra which was decreased with guanethidine (10(-6) M) and further blocked by atropine (10(-6) M). In the presence of both, a relaxation response was observed that is sensitive to NOS inhibitors especially at low frequencies. EFS induced a relaxation followed by a contraction in IAS strips. This contraction was blocked by guanethidine but not by atropine, and the remaining relaxation at 20 Hz was decreased with L-NOARG and increased with L-arginine. There are differences between urethra and IAS in terms of muscarinic activation and neural innervation, relevant for pharmacotherapy. © 2010 Wiley-Liss, Inc.

  15. Improved sphincter contractility after allogenic muscle-derived progenitor cell injection into the denervated rat urethra.

    Science.gov (United States)

    Cannon, Tracy W; Lee, Ji Youl; Somogyi, George; Pruchnic, Ryan; Smith, Christopher P; Huard, Johnny; Chancellor, Michael B

    2003-11-01

    To study the physiologic outcome of allogenic transplant of muscle-derived progenitor cells (MDPCs) in the denervated female rat urethra. MDPCs were isolated from muscle biopsies of normal 6-week-old Sprague-Dawley rats and purified using the preplate technique. Sciatic nerve-transected rats were used as a model of stress urinary incontinence. The experimental group was divided into three subgroups: control, denervated plus 20 microL saline injection, and denervated plus allogenic MDPCs (1 to 1.5 x 10(6) cells) injection. Two weeks after injection, urethral muscle strips were prepared and underwent electrical field stimulation. The pharmacologic effects of d-tubocurare, phentolamine, and tetrodotoxin on the urethral strips were assessed by contractions induced by electrical field stimulation. The urethral tissues also underwent immunohistochemical staining for fast myosin heavy chain and CD4-activated lymphocytes. Urethral denervation resulted in a significant decrease of the maximal fast-twitch muscle contraction amplitude to only 8.77% of the normal urethra and partial impairment of smooth muscle contractility. Injection of MDPCs into the denervated sphincter significantly improved the fast-twitch muscle contraction amplitude to 87.02% of normal animals. Immunohistochemistry revealed a large amount of new skeletal muscle fiber formation at the injection site of the urethra with minimal inflammation. CD4 staining showed minimal lymphocyte infiltration around the MDPC injection sites. Urethral denervation resulted in near-total abolishment of the skeletal muscle and partial impairment of smooth muscle contractility. Allogenic MDPCs survived 2 weeks in sciatic nerve-transected urethra with minimal inflammation. This is the first report of the restoration of deficient urethral sphincter function through muscle-derived progenitor cell tissue engineering. MDPC-mediated cellular urethral myoplasty warrants additional investigation as a new method to treat stress urinary

  16. Relación entre Capacidad Aeróbica e Índices Antropométricos en los Trabajadores Manuales Venezolanos

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    Francisco José Burgos Navarrete

    2016-07-01

    Full Text Available Al iniciar el presente estudio no se encontró literatura nacional sobre data antropométrica de los trabajadores manuales venezolanos, que determinase la relación entre la potencia aeróbica o capacidad aeróbica relativa (mlO2/kg-min, ni la capacidad aeróbica absoluta (kcal/min vs los índices antropométricos: edad, estatura, sexo, masa corporal, perímetro abdominal, índice de masa corporal, frecuencia cardíaca después del ejercicio. En este contexto el objetivo de esta investigación fue determinar la asociación entre la capacidad aeróbica vs los índices antropométricos escogidos. Marco metodológico: el paradigma es el cuantitativo, su tipo es correlacional, con diseño de campo, epidemiológico y de corte transversal. La Capacidad aeróbica relativa es un parámetro fisiológico de competencia personal de umbral o, un índice de salud. A partir de la Capacidad aeróbica relativa se deduce matemáticamente la Capacidad aeróbica absoluta, la cual indica la capacidad para sostener un consumo metabólico en trabajos físicos durante períodos de tiempo variable, se evaluó la Capacidad aeróbica relativa empleando la prueba del escalón (USDA Forest Service Step Test, participantes: 40 hombres y 33 mujeres, de 20 a 59 años de edad. En los hombres la Capacidad aeróbica relativa, la Capacidad aeróbica absoluta, el perímetro abdominal y el índice de masa corporal fueron mayores que en las mujeres. Mostraron correlaciones negativas: 1. la Capacidad aeróbica relativa vs los índices: edad, perímetro abdominal, Índice de masa corporal, frecuencia cardíaca después del ejercicio; 2. la Capacidad aeróbica absoluta vs edad, perímetro abdominal, frecuencia cardíaca después del ejercicio; sin embargo, la correlación resultó positiva entre Capacidad aeróbica absoluta vs índice de masa corporal. Fue posible obtener dos ecuaciones, ambas con R2 = 0,78, predictoras de las Capacidad aeróbica absoluta para ambos sexos y a partir de

  17. Protective effects of anisodamine on cigarette smoke extract-induced airway smooth muscle cell proliferation and tracheal contractility

    International Nuclear Information System (INIS)

    Xu, Guang-Ni; Yang, Kai; Xu, Zu-Peng; Zhu, Liang; Hou, Li-Na; Qi, Hong; Chen, Hong-Zhuan; Cui, Yong-Yao

    2012-01-01

    Anisodamine, an antagonist of muscarinic acetylcholine receptors (mAChRs), has been used therapeutically to improve smooth muscle function, including microvascular, intestinal and airway spasms. Our previous studies have revealed that airway hyper-reactivity could be prevented by anisodamine. However, whether anisodamine prevents smoking-induced airway smooth muscle (ASM) cell proliferation remained unclear. In this study, a primary culture of rat ASM cells was used to evaluate an ASM phenotype through the ability of the cells to proliferate and express contractile proteins in response to cigarette smoke extract (CSE) and intervention of anisodamine. Our results showed that CSE resulted in an increase in cyclin D1 expression concomitant with the G0/G1-to-S phase transition, and high expression of M2 and M3. Functional studies showed that tracheal hyper-contractility accompanied contractile marker α-SMA high-expression. These changes, which occur only after CSE stimulation, were prevented and reversed by anisodamine, and CSE-induced cyclin D1 expression was significantly inhibited by anisodamine and the specific inhibitor U0126, BAY11-7082 and LY294002. Thus, we concluded that the protective and reversal effects and mechanism of anisodamine on CSE-induced events might involve, at least partially, the ERK, Akt and NF-κB signaling pathways associated with cyclin D1 via mAChRs. Our study validated that anisodamine intervention on ASM cells may contribute to anti-remodeling properties other than bronchodilation. -- Highlights: ► CSE induces tracheal cell proliferation, hyper-contractility and α-SMA expression. ► Anisodamine reverses CSE-induced tracheal hyper-contractility and cell proliferation. ► ERK, PI3K, and NF-κB pathways and cyclin D1 contribute to the reversal effect.

  18. Effects of Crocetin Esters and Crocetin from Crocus sativus L. on Aortic Contractility in Rat Genetic Hypertension

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    Silvia Llorens

    2015-09-01

    Full Text Available Background: Endothelial dysfunction, characterized by an enhancement in vasoconstriction, is clearly associated with hypertension. Saffron (Crocus sativus L. bioactive compounds have been recognized to have hypotensive properties. Recently, we have reported that crocetin exhibits potent vasodilator effects on isolated aortic rings from hypertensive rats. In this work, we have aimed to analyze the anticontractile ability of crocetin or crocetin esters pool (crocins isolated from saffron. Thus, we have studied the effects of saffron carotenoids on endothelium-dependent and -independent regulation of smooth muscle contractility in genetic hypertension. Methods: We have measured the isometric responses of aortic segments with or without endothelium obtained from spontaneously hypertensive rats. The effects of carotenoids were studied by assessing the endothelial modulation of phenylephrine-induced contractions (10−9–10−5 M in the presence or absence of crocetin or crocins. The role of nitric oxide and prostanoids was analyzed by performing the experiments with L-NAME (NG-nitro-l-arginine methyl ester or indomethacin (both 10−5 M, respectively. Results: Crocetin, and to a minor extent crocins, diminished the maximum contractility of phenylephrine in intact rings, while crocins, but not crocetin, increased this contractility in de-endothelizated vessels. In the intact vessels, the effect of crocetin on contractility was unaffected by indomethacin but was abolished by L-NAME. However, crocetin but not crocins, lowered the already increased contractility caused by L-NAME. Conclusions: Saffron compounds, but especially crocetin have endothelium-dependent prorelaxing actions. Crocins have procontractile actions that take place via smooth muscle cell mechanisms. These results suggest that crocetin and crocins activate different mechanisms involved in the vasoconstriction pathway in hypertension.

  19. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy.

    Science.gov (United States)

    Kandadi, Machender R; Yu, Xuejun; Frankel, Arthur E; Ren, Jun

    2012-11-07

    Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Wild type (WT) and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.)). Cardiomyocyte contractile and intracellular Ca(2+) properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca(2+) handling), the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca(2+) anomalies, possibly through regulation of autophagy and mitochondrial function.

  20. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

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    Kandadi Machender R

    2012-11-01

    Full Text Available Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT and cardiac-specific catalase overexpression mice were challenged with lethal toxin (2 μg/g, intraperotineally (i.p.. Cardiomyocyte contractile and intracellular Ca2+ properties were assessed 18 h later using an IonOptix edge-detection system. Proteasome function was assessed using chymotrypsin-like and caspase-like activities. GFP-LC3 puncta and Western blot analysis were used to evaluate autophagy and protein ubiquitination. Results Lethal toxin exposure suppressed cardiomyocyte contractile function (suppressed peak shortening, maximal velocity of shortening/re-lengthening, prolonged duration of shortening/re-lengthening, and impaired intracellular Ca2+ handling, the effects of which were alleviated by catalase. In addition, lethal toxin triggered autophagy, mitochondrial and ubiquitin-proteasome defects, the effects of which were mitigated by catalase. Pretreatment of cardiomyocytes from catalase mice with the autophagy inducer rapamycin significantly attenuated or ablated catalase-offered protection against lethal toxin-induced cardiomyocyte dysfunction. On the other hand, the autophagy inhibitor 3-MA ablated or significantly attenuated lethal toxin-induced cardiomyocyte contractile anomalies. Conclusions Our results suggest that catalase is protective against anthrax lethal toxin-induced cardiomyocyte contractile and intracellular Ca2+ anomalies, possibly through regulation of autophagy and mitochondrial function.

  1. Parasympathetic neurons in the cranial medial ventricular fat pad on the dog heart selectively decrease ventricular contractility.

    Science.gov (United States)

    Dickerson, L W; Rodak, D J; Fleming, T J; Gatti, P J; Massari, V J; McKenzie, J C; Gillis, R A

    1998-05-28

    We hypothesized that selective control of ventricular contractility might be mediated by postganglionic parasympathetic neurons in the cranial medial ventricular (CMV) ganglion plexus located in a fat pad at the base of the aorta. Sinus rate, atrioventricular (AV) conduction (ventricular rate during atrial pacing), and left ventricular contractile force (LV dP/dt during right ventricular pacing) were measured in eight chloralose-anesthetized dogs both before and during bilateral cervical vagus stimulation (20-30 V, 0.5 ms pulses, 15-20 Hz). Seven of these dogs were tested under beta-adrenergic blockade (propranolol, 0.8 mg kg(-1) i.v.). Control responses included sinus node bradycardia or arrest during spontaneous rhythm, high grade AV block or complete heart block, and a 30% decrease in contractility from 2118 +/- 186 to 1526 +/- 187 mm Hg s(-1) (P 0.05) decrease in contractility but still elicited the same degree of sinus bradycardia and AV block (N = 8, P < 0.05). Five dogs were re-tested 3 h after trimethaphan fat pad injection, at which time blockade of vagally-induced negative inotropy was partially reversed, as vagal stimulation decreased LV dP/dt by 19%. The same dose of trimethaphan given either locally into other fat pads (PVFP or IVC-ILA) or systemically (i.v.) had no effect on vagally-induced negative inotropy. Thus, parasympathetic ganglia located in the CMV fat pad mediated a decrease in ventricular contractility during vagal stimulation. Blockade of the CMV fat pad had no effect on vagally-mediated slowing of sinus rate or AV conduction.

  2. APRENDIZAJE CON BASE EN PROYECTOS PARA DESARROLLAR CAPACIDADES DE PROBLEMATIZACIÓN EN EDUCACION SUPERIOR

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    Juan Manuel Muñoz Cano

    2011-01-01

    Full Text Available El propósito del estudio fue diseñar una intervención educativa para que los estudiantes superaran las dificultades en el manejo autónomo de la Internet, y que a través de este recurso desarrollaran capacidades para la identificación de los problemas de salud que afectan a la población, así como la búsqueda y análisis de información clínica actualizada. Se trabajó con base en proyectos y la solución de problemas durante cuatro meses con 31 estudiantes a quienes se asesoró en el manejo de bibliotecas virtuales. Se emplearon distintas estrategias en el aula para el trabajo en espacio virtual, como la elaboración del árbol de problemas y el árbol de soluciones. La evaluación formativa facilitó el seguimiento del proceso de aprendizaje y la sistematización de los resultados. La evaluación se apoyó en criterios definidos en matrices de evaluación y en el portafolio de evidencias. La acreditación se realizó con base en la calidad de sus informes. La experiencia la terminaron 14 estudiantes, y 12 de ellos lograron elaborar informes complejos que incluyeron conclusiones y recomendaciones y la consulta de varias fuentes localizadas en bibliotecas virtuales.

  3. Capacidad de las macrofitas Lemna minor y Eichhornia crassipes para eliminar el niquel

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    BRES, P

    2012-04-01

    Full Text Available El objetivo de este trabajo fue estudiar la capacidad de dos especies de macrofitas, Lemna minor y Eichhornia crassipes, para eliminar el níquel. Se realizaron cuatro tratamientos durante dos semanas para cada una de las especies. Las plantas fueron incubadas con 0, 1, 3 y 6 mg l-1 de Ni. Ambas especies mostraron, en todos los tratamientos con Ni, una reducción en la concentración a lo largo del tiempo. L. minor mostró ser más eficiente para remover este ión a la más baja concentración. Sin embargo, en concentraciones más elevadas no se observaron diferencias entre ambas especies. El análisis del tejido de las plantas mostró que las mismas acumulaban el metal, en los tres casos evaluados con concentraciones diferentes.Palabras clave: fitorremediación, metales pesados, plantas acuáticas, acumulación.

  4. CAPACIDAD DE SALTO EN NIÑAS PREPÚBERES QUE PRACTICAN GIMNASIA RÍTMICA

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    R. Arteaga

    2010-10-01

    Full Text Available

    Estudiamos el rendimiento en el salto vertical y como podría verse afectado por lacomposición corporal en 13 niñas que practicaban gimnasia rítmica (GR; 10.4 ± 0.9 años y13 niñas control (CO; 9.9 ± 0.7 años. La composición corporal fue determinada medianteantropometría y DXA. Se realizaron saltos con y sin contramovimiento (CMJ y SJ sobre unaplataforma de fuerza analizándose entre otras variables la altura de vuelo (AV, velocidad dedespegue (VD, velocidad vertical máxima del centro de masas (Vimax, la potencia media(Pm, el impulso mecánico positivo (Ipos, tiempo de fuerza máxima (Tfmax y potenciainstantánea máxima (Pimax. Las gimnastas consiguieron una AV, VD, Ipos y Vimax mayoren ambos saltos y una Pm, Tfmax y Pimax mayores en el CMJ que las control (p<0.05. Enconclusión, prácticar gimnasia rítmica 10 h·sem-1 se asocia a un mayor rendimiento en elsalto vertical.

    Palabras claves: gimnasia rítmica, entrenamiento de fuerza, capacidad de salto.

  5. Análisis de la capacidad de aceleración en mujeres atletas de modalidades de velocidad

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    Gerard Carmona Dalmases

    2012-03-01

    Full Text Available Objetivos. Caracterizar la capacidad de aceleración con relación al rendimiento (tiempo en sprint de 30 m, la velocidad máxima y las manifestaciones de fuerza (capacidad de salto y potencia (en ½ squat musculares en 4 mujeres atletas de especialidades de velocidad de nivel nacional. Métodos. Se realizaron dos días de pruebas (pista y laboratorio. Se valoró la capacidad de aceleración (velocidades instantánea a 1, 2 y 3 s –vi1, vi2 i vi3–, aceleración inicial (ainicial, tiempo de sprint en 30 m (rendimiento, velocidad máxima (vmàx, capacidad de salto (SJ, CMJ, LJ bw y RJ 5s y potencia media máxima (Pm màx desarrollada en ½ squat. Resultados. Se hallaron correlaciones significativas entre el rendimiento (t30m y la vmáx (r = –0,980; P < 0,01, la capacidad de aceleración (velocidades instantáneas y el t30m (r = –0,954; P < 0,05 y la vmáx (r = 0,992 y 0,979; P < 0,01 y 0,05, la manifestación elástica de la fuerza (CMJ y el t30m (r = –0,983; P < 0,05 y la fuerza dinámica máxima relativa y la ainicial (r = 0,980; P < 0,01. Conclusiones. El principal hallazgo del presente estudio fue que la vmáx era el mayor determinante del t30m. También la capacidad de aceleración, sobretodo la vi2, y el CMJ tuvieron una gran ascendencia sobre el t30m y la vmáx.

  6. Determinantes de la capacidad de innovación en PYMES regionales Determinants of innovativeness in regional SMES

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    Carlos Maria Fernández-Jardón

    2013-03-01

    Full Text Available DOI: 10.5902/198346597689La capacidad de innovación es una competencia distintiva que permite innovar y, en consecuencia, potencia la competitividad, especialmente en las pequeñas y medianas empresas (PYME. Dicha capacidad se ve condicionada por factores internos y externos. Este artículo analiza como combina la empresa dichos factores para mejorar la capacidad de innovación. Por un lado, la empresa genera una competencia distintiva denominada gestión de los recursos humanos y tecnológicos a partir del capital intelectual interno. Por otro lado, organiza otra competencia distintiva denominada gestión de los recursos y relaciones territoriales a partir de los recursos tangibles asociados al territorio y del capital intelectual fruto de las relaciones con el entorno. Mediante técnicas de Mínimos cuadrados parciales aplicados  en una muestra de pequeñas y medianas empresas en una región del noroeste de España se demuestra que ambos factores influyen en la capacidad de innovación. Este estudio contribuye a delimitar cuales son los factores que potencian la capacidad de innovación y como la empresa asocia esos factores, indicando cual es el proceso de construcción de competencias básicas para mejorar su capacidad de innovación. Como consecuencia, sugiere elementos de reflexión para elaborar políticas de apoyo a la innovación empresarial.The innovativeness is a core competence to innovate and therefore enhancing competitiveness, especially in small and medium enterprises (SMEs. This capability is constrained by internal and external factors. This article discusses how the company combines these factors to improve innovativeness. First, the company generates a core competence called human resource management and technology from internal intellectual capital. Furthermore, the company organizes another core competence called resource management and territorial relations from tangible resources associated with intellectual capital

  7. Occupational stress and work capacity of nurses of a hospital group Estrés laboral y capacidad para el trabajo de enfermeros de un grupo hospitalario Estresse laboral e capacidade para o trabalho de enfermeiros de um grupo hospitalar

    Directory of Open Access Journals (Sweden)

    Christian Negeliskii

    2011-06-01

    Full Text Available The study aimed to evaluate the relationship between occupational stress and the work capacity index of 368 nurses (82.1% of the population of a Hospital Group. A questionnaire with socio-occupational questions was used as well as two scales: the Job Stress Scale and the Work Capacity Index. The group of nurses was predominantly female (93.2%, worked in care activities (63.9%, had undertaken at least one Postgraduate course (76% and were satisfied with the unit where they worked (70.5%. Occupational stress was present in 23.6% of the nurses, of these 15.2% presented High Strain work and 8.4% Passive Work. Social Support exercised a significant positive influence on all groups - exposed or not to occupational stress. Regarding the Work Capacity, this was Moderate (28-36 points for 51.4% of the nurses and Good (37-43 points for 47.4%. There was no correlation between stress and work capacity.Se trata de un estudio con objetivo de evaluar la relación entre el estrés laboral y el índice de capacidad para el trabajo de 368 enfermeros (82,1% de la población de un Grupo Hospitalario. Se utilizó un cuestionario con cuestiones socio ocupacionales y dos escalas: la Job Stress Scale y el Índice de Capacidad para el Trabajo. El grupo de enfermeros es predominantemente femenino (93,2%, trabaja en actividades asistenciales (63,9%, posee por lo menos un curso de posgraduación (76% y está satisfecho con la unidad donde trabaja (70,5%. El estrés laboral está presente en 23,6% de los enfermeros, de estos 15,2% presentan Alta Exigencia en el trabajo y 8,4% Trabajo Pasivo. El Apoyo Social ejerce influencia positiva significativa sobre todos los grupos expuestos y no expuestos al estrés laboral. En cuanto a la Capacidad para el Trabajo, está es Moderada (28-36 puntos para 51,4% de los enfermeros y Buena (37-43 puntos para 47,4%. No se encontró correlación entre el estrés y la capacidad para el trabajo.Este estudo teve como objetivo avaliar a rela

  8. Capacidade institucional: uma revisão de conceitos e programas federais de governo para o fortalecimento da administração pública

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    Fabiana Silva Fernandes

    Full Text Available Resumo Este artigo é uma revisão de conceitos sobre a capacidade institucional e de alguns programas federais implementados para fortalecer a capacidade institucional de estados, municípios e órgãos da administração pública. Para a elaboração deste trabalho, realizou-se um levantamento bibliográfico e documental sobre, respectivamente, o conceito de capacidade institucional e os programas e ações do governo federal para o fortalecimento de sua capacidade institucional. Verificou-se que o conceito tem caráter polissêmico e pragmático e foi desenvolvido para mensurar e elaborar estratégias de fortalecimento da capacidade das instituições. Da mesma forma, notou-se a existência de estreita vinculação entre capacidade institucional e capacidade de planejamento e de gestão das políticas públicas.

  9. Una propuesta metodológica para la determinación de capacidades estratégicas en pymes industriales

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    Carolina Saavedra Sueldo

    2014-07-01

    Full Text Available Una forma para evaluar los problemas internos de las empresas y conocer las fuentes de sus ventajas competitivas es estudiar sus recursos y capacidades. Los recursos son la base de las capacidades, y estas se pueden desarrollar y transformar en capacidades estratégicas que llevan a la obtención de una ventaja o igualdad competitiva. En este trabajo se propone una metodología para determinar y valorar las capacidades actuales de pymes industriales de una región argentina, para después conocer su efecto competitivo. Para ello, se definen cuatro capacidades principales denominadas directiva, innovación, comercialización e integración, que a su vez se dividen en subcapacidades compuestas por recursos. Estas capacidades se evalúan para determinar si están presentes en las empresas motivo de estudio. Posteriormente se aplica el test VRIO para definir la consecuencia competitiva de las mismas. La metodología desarrollada sistematiza la evaluación de capacidades estratégicas en el marco de la teoría de recursos.

  10. Capacidades institucionales y desempeño de los organismos operadores de agua en Hermosillo, Sonora, y Mexicali, Baja California

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    Edmundo Loera Burnes

    2017-01-01

    Full Text Available Con el enfoque de capacidad institucional, aquí se analizan los factores políticos que influyeron en la asignación de recursos jurídicos, organizacionales y humanos para la Comisión Estatal de Servicios Públicos de Mexicali y para Agua de Hermosillo. También cómo influye el titular del Ejecutivo en su operación, y cómo se refleja la influencia de los factores institucionales en su desempeño. Si bien el estudio muestra la baja capacidad de ambos organismos en el aspecto de recursos humanos, el de Mexicali es superior en los otros rubros, y eso se traduce en más planeación y, por lo tanto, en mejor desempeño.

  11. Inteligencia y memoria de trabajo: la relación entre factor g, complejidad cognitiva y capacidad de procesamiento

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    Colom Roberto

    2001-01-01

    Full Text Available La psicologia experimental ha estudiado extensivamente las características de la memoria, mientras que la psicología correlacional ha actualizado las principales propiedades de la inteligencia. El acercamiento entre ambos enfoques se basa en el análisis de las relaciones entre un concepto nuclear de la memoria -- la memoria de trabajo -- y el principal ingrediente del concepto psicométrico de inteligencia -- el factor g. Las evidencias disponibles sugieren que las diferencias individuales en g podrían ser explicadas por los conceptos cognitivos de capacidad y de velocidad asociados a la memoria de trabajo. Esas evidencias sugieren nuevos modos de mejorar la inteligencia -- y, por tanto, los correlatos asociados a ella -- a través del incremento de la capacidad del sistema para procesar información de manera eficiente.

  12. Modelo de gestión del conocimiento para medir la capacidad productiva en grupos de investigación

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    Fredy Eduardo Vásquez Rizo

    2010-01-01

    Full Text Available Las organizaciones actuales manejan y producen numerosos datos e información. Muchos de estos elementos son subutilizados o despreciados al carecer de mecanismos y/o procesos para transformarlos en conocimiento útil. El estudio que se expone se centra en datos e información relacionados con la capacidad productiva de los grupos de investigación de una universidad colombiana (Universidad Autónoma de Occidente- UAO, utilizándolos para la generación de conocimiento valioso, a través de la construcción de un modelo. Este modelo, basado en indicadores, permite medir dicha capacidad productiva y sugerir algunas opciones para potenciar sus posibilidades de éxito en las convocatorias colombianas de reconocimiento y medición de grupos de investigación, establecidas por el Departamento Administrativo de Ciencia, Tecnología e Innovación-Colciencias.

  13. Actividad física y capacidad funcional en el adulto mayor: el taekwondo como alternativa de mejoramiento

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    Pedro Carazo Vargas

    2001-01-01

    Full Text Available Con el envejecimiento se presenta una serie decambios de orden fisiológico, psicológico y social, capacesde reducir la capacidad para efectuar eficientemente lastareas de la vida diaria. En la presente revisión de litera-tura se realiza una descripción de estas modificaciones,así como una recopilación de los principales efectos de laactividad física sobre la capacidad funcional del adultomayor. Se analizan los primeros indicios que señalan altaekwondo como una importante alternativa para mejo-rar el desempeño en las tareas de la vida diaria y a la vezse recomiendan las principales pautas a seguir para in-vestigar la temática

  14. COMPLEMENTARIEDAD FORMATIVA EN LAS CAPACIDADES ORGANIZATIVAS: CREACIÓN DE CONOCIMIENTO Y FLEXIBILIDAD DEL RECURSO HUMANO EN LAS EMPRESAS DE ALTA TECNOLOGÍA

    OpenAIRE

    Pérez de Miguel, A; Sáiz Bárcena, L.

    2010-01-01

    En este estudio se teoriza e investiga empíricamente sobre un marco avanzado de análisis de los procesos formativos de las capacidades, para la determinación de su grado de complementariedad formativa, como punto de partida para una eficiente gestión de las capacidades organizativas. Los resultados sobre 136 organizaciones españolas de alta tecnología superaron las expectativas, puesto que demostraron, al mismo tiempo y sin efectos contrarios, la formación de una capacidad objetivo y de su ho...

  15. APRENDIZAJE Y ACUMULACIÓN DE CAPACIDADES TECNOLÓGICAS EN UN GRUPO DEL SECTOR SIDERÚRGICO

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    Rodrigo Ortega Rangel

    2005-12-01

    Full Text Available El aprendizaje y la acumulación de capacidades tecnológicas son unos de los rasgos que integran la sociedad del conocimiento actual. Por ello son parte fundamental de la competitividad entre países, regiones y empresas. El aprendizaje y la acumulación de capacidadesimplican un proceso de desarrollo de capacidades internas que se construyen a partir de esfuerzos propios y de la experiencia y conocimientos disponibles desarrollados por la propia empresa u otras instituciones para generar innovaciones;son, por lo tanto, elementos fundamentales de la competitividad.La regularidad con la que una empresa incorpora mejoras radicales o incrementales en sus productos, procesos o esquemas organizacionales es factor decisivo para el crecimiento de su productividad. Este trabajo analiza el proceso de innovación desde una perspectiva interna, para elucidar la forma en que un grupo industrial del sector siderúrgico desarrolla sus capacidades tecnológicas a través del ejercicio de sus funciones técnicas de inversión, producción y soporte. “Los procesos de aprendizaje comprenden el aprendizaje por la práctica (aumentar por ejemplo, la eficiencia de las operaciones de producción, el aprendizaje por el uso (por ejemplo, utilizar más eficientemente los equipos complejos, el aprendizaje por interacción (asociando usuarios y productores en una interacción en el desarrollo de nuevos productos, y hasta el aprendizaje por aprendizaje, donde la capacidad de las empresas en asimilar las innovaciones realizadas en otra parte depende de su experiencia en materia de aprendizaje, enriquecida por la I&D o por otras inversiones inmateriales”

  16. TEORÍA DE LA MENTE EN NIÑOS PREESCOLARES: DIFERENCIAS ENTRE SEXOS Y CAPACIDAD DE MEMORIA DE TRABAJO

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    Michael Padilla-Mora

    2009-01-01

    Full Text Available La teoría de la mente refiere a la habilidad para predecir y explicar el comportamiento de los demás, haciendo referencia a sus estados mentales internos, y es considerada como un aspecto fundamental del desarrollo cognitivo durante los años preescolares. Por otra parte, la capacidad de memoria de trabajo es un sistema que permite mantener en mente un determinado número de representaciones de manera simultánea, y también constituye una habilidad central para el desarrollo cognitivo de la población preescolar. En esta investigación se analizan las relaciones entre el desarrollo de la teoría de la mente y la capacidad de memoria de trabajo en 60 niños y niñas preescolares de entre 5 y 7 años, enfatizando posibles diferencias asociadas con el sexo de los participantes. Para la evaluación de la teoría de la mente se utilizaron 6 pruebas de falsa-creencia, mientras la capacidad de memoria de trabajo fue evaluada por medio de 2 tareas de señalamiento autoordenado. Los resultados revelan diferencias entre los sexos en el desarrollo de la teoría de la mente, y descartan la asociación entre esa misma habilidad y la capacidad de memoria de trabajo. Estos hallazgos se discuten en el contexto del debate actual respecto al de sarrollo de la teoría de la mente y las diferencias entre los sexos en el desarrollo cognitivo.

  17. Um modelo de simulação para gestão da capacidade dos aeroportos brasileiros

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    Antonio Rodolfo Araujo Marcos

    Full Text Available A importância do setor aéreo para o desenvolvimento de um país e o crescimento da demanda aérea brasileira implica na necessidade de uma gestão eficiente dos aeroportos, buscando o equilíbrio entre a capacidade e a demanda aérea. Diante disso, este artigo apresenta um modelo em Dinâmica de Sistemas capaz de auxiliar a gestão aeroportuária brasileira em relação ao dimensionamento dos subsistemas de um aeroporto (Terminal de Passageiros, Pistas e Pátio. O modelo utiliza dados sobre demanda aérea de passageiros, número médio de passageiros por voo, demanda hora-pico, nível de serviço do terminal de passageiros e tempo médio de estacionamento das aeronaves para analisar a situação de treze aeroportos brasileiros. Por fim, através da comparação da capacidade ideal produzida pelo modelo de simulação com a capacidade real instalada, o artigo classifica a situação de cada um dos subsistemas dos aeroportos estudados em adequada, crítica e preocupante. Entre os principais resultados obtidos pode-se destacar que: a Pista é o subsistema que apresenta melhores condições, enquanto que o terminal de passageiros é o subsistema em pior condição; os investimentos e aumento da capacidade são insuficientes para atender uma demanda de crescimento de 5% ao ano na hora-pico.

  18. Planificación estratégica de la capacidad en una empresa del sector limentación

    OpenAIRE

    Companys Pascual, Ramón; Ribas Vila, Immaculada; Bautista Valhondo, Joaquín

    2012-01-01

    En esta comunicación se describe el procedimiento propuesto a una empresa del sector de la alimentación para planificar la capacidad productiva de las diferentes plantas aprovechando el cambio de ubicación forzoso de una de ellas. El caso de estudio puede servir de referencia a otros profesionales que se enfrenten a una situación semejante.

  19. La relación entre la capacidad de atencion dividida y la estimación prospectiva del tiempo

    OpenAIRE

    Susana Celeste Azzollini; Federico Faustino González; María Emilia Gómez

    2004-01-01

    Se realizó una investigación cuyo objetivo fue determinar si la capacidad de atención dividida resultaba explicativa de la variabilidad de las estimaciones prospectivas del tiempo. Los modelos teóricos sobre dicha estimación postulan que los recursos atencionales de procesamiento están divididos entre un procesador temporal, que cuenta y almacena unidades temporales subjetivas (Subjective Temporal Units - STUs) y otras actividades de procesamiento no temporal (Zakay, 1993...

  20. CAPACIDAD ANTAGÓNICA Y QUITINOLÍTICA DE MICROORGANISMOS AISLADOS DE RESIDUOS DE HIGUERILLA (Ricinus communis

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    TERESA CABRA C

    2014-06-01

    Full Text Available Se ha comprobado que los fertilizantes y controladores biológicos a base de microorganismos benéficos productores de metabolitos de interés, inducen el crecimiento vegetal y actúan contra microorganismos patógenos y plagas que afectan los agroecosistemas. Por lo tanto, su uso constituye una práctica eficiente de producción limpia que ayuda a reducir el impacto ambiental causado por el uso de agroquímicos. En este trabajo se evaluó la capacidad antagónica y quitinolítica de 15 cepas bacterianas y una levaduriforme, aisladas de residuos lignocelulósicos de higuerilla (Ricinus communis. La actividad antagónica de cada cepa se determinó por la capacidad de inhibir el crecimiento del hongo fitopatógeno Fusarium equiseti, en medio de cultivo PDA. Solamente la bacteria Bacillus subtilis, presentó una inhibición significativa del crecimiento del hongo equivalente al 76,08%. Por lo tanto se demuestra que la cepa de Bacillus subtilis puede ser empleada en la formulación de inoculantes microbianos. La capacidad quitinolítica de las cepas se definió por el crecimiento del microorganismo y por la formación de halos de hidrólisis alrededor de las colonias sobre el medio de cultivo suplementado con quitina coloidal. Ninguna de las cepas evaluadas mostró capacidad para degradar quitina.

  1. Capacidades de investigación sobre determinantes sociales de la salud en Brasil, Colombia y México

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    Elis Borde

    2016-09-01

    Full Text Available Objetivo: analizar las capacidades de investigación sobre determinantes sociales y determinación social de los procesos salud-enfermedad (dss en Brasil, Colombia y México con base en los sistemas nacionales de ciencia, tecnología e innovación (sncti y la producción científica sobre dss (2005- 2012 de cada país. Metodología: se realiza un estudio exploratorio a partir de revisión de literatura, consulta de plataformas nacionales de cada sncti, entrevistas y foros de consulta, contemplando las siguientes categorías de estudio para de analizar las capacidades de: 1. Producción científica, formación de investigadores y políticas relativas a capacidades de investigación; 2. Redes de colaboración; 3. Infraestructura para la investigación y 4. Producción y apropiación social del conocimiento. Resultados y discusión: La investigación sobre dss se divulga principalmente en revistas científicas de circulación nacional, en Brasil y Colombia, mientras que en México se publica principalmente en revistas extranjeras. Los tres países cuentan con sncti consolidados, sin embargo, son escasos los montos de financiamiento para investigación sobre dss. Conclusiones: es necesario articular acciones de fortalecimiento de capacidades de investigación, fortaleciendo redes y posicionando los dss en agendas estratégicas.

  2. Processo ensino-aprendizagem da técnica de palpação e mensuração uterina: influência da prática The teaching-learnin process of the uterine measurement and palpation techinique: the influence practice

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    Clarice Heiko Muramatsu

    1996-12-01

    Full Text Available O presente estudo relacionado ao processo ensino-aprendizagem da técnica de palpação e mensuração uterina, teve como objetivos, analisar a influência da prática em relação à habilidade e analisar o conhecimento adquirido da técnica dos estudantes de Graduação em Enfermagem. Aplicando o "modelo padrão" elaborado para este estudo, os estudantes foram avaliados em 2 etapas; os resultados obtidos permitiram concluir pela importância da prática no processo ensino-aprendizagem de uma habilidade perceptivo-motora, verificada através da melhora do desempenho dos estudantes em relação à habilidade e ao conhecimento adquirido.The present study related to the teaching-learning process concerning the uterine measurement and palpation technique, it was intended to analyze the influence practice had on the Undergraduation Nursing students' skills acquired knowledge by the use of that technique. Applying a standard instrument previously developed for this study, the students' evaluation was 'carried out in two phases. The results showed a significant improvement in the students' performance skills and descriptive knowledge. Thus, this study was able to stress the importance of practice for the motorperceptive skills in the teaching-learning process.

  3. Fatores associados às alterações cérvico-uterinas de mulheres atendidas em um município polo do oeste catarinense Factors associated to uterine-cervix changes in women assisted in a pole town in western Santa Catarina

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    Rafaela Bedin

    2017-01-01

    Full Text Available Objetivo: Identificar as alterações cérvico-uterinas nos exames citopatológicos e seus fatores associados. Métodos: Estudo retrospectivo realizado pela análises dos exames citopatológicos registrados no Sistema de Informação do Câncer no sul do país em 2014. A amostra final resultou em 1.157 laudos. Para a análise dos dados foi utilizado o software SSPP. O estudo foi aprovado pelo Comitê de Ética e Pesquisa com seres humanos da Universidade Federal da Fronteira Sul sob CAAE nº 46421815.0.0000.5564. Resultados: Predominou nas amostras os lactobacilos como agentes microbiológicos e a Gardnerella vaginalis como agente infeccioso. O colo uterino alterado, a presença de células metaplásicas associado ao diagnóstico de metaplasia foi prevalente nas mulheres de 25 a 34 anos. As inflamações(18,9%, seguido dos achados citológicos(11,8% foram as alterações mais frequentes. Conclusão: Associaram-se ao risco de ocorrência das alterações celulares idade entre 25 a 64 anos, uso da pílula anticoncepcional, Terapia de Reposição Hormonal e epitélio metaplásico.

  4. Alterações histoquímicas das glicosaminoglicanas na cérvice uterina no final da prenhez da rata albina após ministração local de hialuronidase Histochemical changes of the glycosaminoglycans in the uterine cervix of pregnant rats after local injection of hyaluronidase

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    Viviane Almeida de Alcântara Lopes

    2008-07-01

    Full Text Available OBJETIVO: estudar as alterações histoquímicas relacionadas às glicosaminoglicanas da cérvice uterina da rata albina, após ministração local de hialuronidase no final da prenhez. MÉTODOS: dez ratas com teste de prenhez positivo foram distribuídas aleatoriamente em dois grupos, numericamente iguais. O Grupo Controle (Gc foi constituído pelas ratas que receberam 1 mL de água destilada, dose única, no 18º dia da prenhez, sob anestesia, ministrado na cérvice uterina. O Grupo Experimental (Gex constou de ratas que receberam, sob as mesmas condições do Gc, 0,02 mL de hialuronidase, diluído em 0,98 mL de água destilada (total de 1 mL. No 20º dia de prenhez, as ratas foram novamente anestesiadas e submetidas à dissecção, preparando-se a cérvice uterina para estudo histoquímico com coloração de alcian blue e seus bloqueios (pH=0,5, pH=2,5, metilação e saponificação. RESULTADOS: verificou-se na lâmina própria no Gc, reação fortemente positiva (+3 e, no Gex, reação negativa, na coloração de alcian blue no pH=0,5. Em pH=2,5 a coloração também se apresentou fortemente positiva (+4 no Gc e fracamente positiva (+1 no Gex. Após metilação, tanto o Gc quanto o Gex mostraram reação negativa após coloração de alcian blue no pH=2,5. Com a reação de metilação seguida de saponificação e na digestão enzimática em lâmina, a coloração da lâmina própria se mostrou negativa em ambos os grupos. CONCLUSÕES: há uma nítida predominância de glicosaminoglicanas sulfatadas no Gc em relação ao Gex e uma tênue quantidade de glicosaminoglicanas carboxiladas identificadas no Gex. As modificações evidenciadas na matriz extracelular sugerem que a hialuronidase injetada localmente na cérvix uterina promoveu alterações bioquímicas compatíveis com maturação cervical.PURPOSE: to study the histochemical changes related to the uterine cervix glycosaminoglycan of the albino female rat, after local ministration of

  5. Correlation between the Doppler velocimetry findings of the uterine arteries during the first and second trimesters of pregnancy Correlação entre os achados doppplervelocimétricos das artérias uterinas no primeiro e segundo trimestres da gestação

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    Adolfo Wenjaw Liao

    2009-01-01

    Full Text Available OBJECTIVES: Evaluate the feasibility of transvaginal uterine artery Doppler examination in the first and second trimesters of pregnancy, establish reference ranges in a Brazilian population and examine the correlation between these Doppler findings. METHODS: Longitudinal prospective study at the antenatal clinic of a tertiary teaching hospital. Uterine artery Doppler examinations were carried out transvaginally at 11 to 14 weeks and 20 to 25 weeks of gestation. Uterine artery mean pulsatility index (PI distributions were determined and the presence or absence of an early diastolic notch was also noted. The degree of correlation between first and second trimester Doppler findings was examined. RESULTS: Three hundred and forty four women with live singleton pregnancies and normal outcome were first examined at a mean gestation of 12.7 weeks. The values corresponding to the 50th and 95th centiles of mean PI were 1.69 and 2.48. Bilateral notches were observed in 44% of cases and unilateral notches were present in 19%. Second trimester Doppler examinations were carried out at a mean gestation of 23.2 weeks and corresponding figures for the 50th and 95th centiles were 1.03 and 1.57. Bilateral notches were noted in 4.4% of the cases. First trimester impedance indices were significantly higher and positively correlated to second trimester findings (r = 0.42, pOBJETIVO: Avaliar a aplicabilidade de realizar exames dopplervelocimétricos endovaginais das artérias uterinas no primeiro e segundo trimestres da gestação, definir valores normais na população brasileira e examinar a correlação entre esses achados. MÉTODOS: Estudo prospectivo longitudinal conduzido em Hospital Universitário Terciário. Os exames dopplervelocimétricos das artérias uterinas foram realizados pela via endovaginal, entre 11 a 14 semanas e 20 a 25 semanas de gestação. Em cada período gestacional estudado, a distribuição dos valores dos índices de pulsatilidade (IP m

  6. Persistencia y capacidad predictiva de márgenes y rotaciones. un análisis empírico

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    Juan Monterrey

    2011-01-01

    Full Text Available En el presente trabajo abordamos el estudio empírico de la persistencia y capacidad predictiva de los componentes margen y rotación de la rentabilidad. A partir de una amplia muestra de compañías españolas, hemos documentado cómo la persistencia de la rotación es superior a la del margen, y cómo los componentes anormales de margen y rotación son menos persistentes que sus componentes sectoriales. Con relación a la capacidad predictiva, nuestros hallazgos confirman que el poder de predicción del margen es más elevado que el de la rotación, aunque su persistencia sea menor. Al separar los componentes sectorial y anormal de margen y rotación hemos comprobado cómo los componentes anormales muestran una capacidad predictiva superior a los componentes sectoriales. Los análisis complementarios muestran el distinto poder predictivo según el signo positivo o negativo de márgenes y rotaciones anormales, y según el signo del resultado, así como la robustez de nuestros hallazgos.

  7. Expressão da capacidade de empatia em bebês de 8 e 18 semanas

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    Kornilia Hatzinikolaou

    2006-04-01

    Full Text Available Este estudo investigou o padrão temporal e expressivo da capacidade de empatia em bebês de 8 e 18 semanas no contexto de interações face-face entre 90 duplas de mãe-bebê. As interações foram analisadas em tempo real e através de micro-análise. Alguns comportamentos infantis apresentaram maior probabilidade de fazerem parte do padrão expressivo da empatia do que outros. Ainda, o padrão expressivo se manifestou diferente em instâncias de empatia com emoções negativas e instâncias de empatia com emoções positivas comunicadas pela mãe. Em relação ao padrão temporal, observou-se que a manifestação da capacidade de empatia ocorreu dentro de um intervalo de tempo igual de ½ segundo antes e 1 segundo depois da mudança emocional da mãe. Os resultados indicam a necessidade de reavaliação das proposições tradicionais sobre as capacidades comunicativas precoces de bebês, e sugerem uma coerência entre os achados e as proposições teóricas contemporâneas na área da Psicologia Infantil.

  8. La limitada capacidad del concepto de populismo punitivo como herramienta de interpretación del sistema penal colombiano

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    Fernando León Tamayo Arboleda

    2016-12-01

    Full Text Available En los intentos por explicar la evolución reciente en la configuración de los sistemas de castigo penal y el reformismo que en esta materia se ha presentado en diversos países del hemisferio occidental, se ha propuesto el concepto de populismo punitivo como herramienta analítica. Sin embargo, su capacidad explicativa parece reducida desde el punto de vista teórico, debido a la dificultad para su determinación y diferenciación de otros conceptos, así como desde el punto de vista práctico, por su insuficiencia para explicar las tendencias recientes en materia de castigo. Por ello, el presente artículo busca problematizar la capacidad analítica que brinda el concepto de populismo punitivo, a partir de un análisis teórico contrastado con las recientes tendencias políticas en Colombia y las reformas penales que mayor impacto han tenido desde la implementación del Código Penal vigente. A partir de lo anterior, se concluye que el concepto de populismo punitivo no representa una novedad frente a otros conceptos previamente utilizados en Colombia, y que su formulación tiene una limitada capacidad para explicar la política criminal en el país.

  9. Capacidade antioxidante de hortaliças usualmente consumidas Antioxidant capacity of vegetables commonly consumed

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    Enayde de Almeida Melo

    2006-09-01

    Full Text Available Como objetivo de avaliar a capacidade antioxidante de 15 hortaliças comercializadas na Cidade do Recife, extratos metanólicos foram testados quanto a atividade antioxidante em sistema modelo beta-caroteno/ácido linoléico e a habilidade de seqüestrar o radical estável 1,1-difenil-2-picrilhidrazil (DPPH. Todas as hortaliças investigadas exibiram propriedade antioxidante, entretanto a ação foi diferenciada entre os vegetais. Os extratos metanólicos da couve folha, tomate, batata, couve-flor, repolho verde, espinafre e alface crespa, com percentual de inibição superior a 70%, foram os mais eficazes em seqüestrar o radical livre. Os extratos metanólicos da alface lisa, cebola branca e vagem apresentaram ação moderada (60-70% de inibição, enquanto que a cebola roxa, chuchu, pepino e cenoura exibiram a mais fraca capacidade de seqüestrar o radical DPPH. No sistema modelo beta-caroteno/ácido linoléico, os extratos metanólicos do espinafre e couve-folha exibiram a mais elevada atividade antioxidante (superior a 70%. Ação antioxidante moderada (60-70% foi exibida pelos extratos da alface lisa, cebola branca e couve-flor, enquanto que os do chuchu, cenoura, pepino, tomate e vagem, com atividade inferior a 60%, foram considerados com fraca ação antioxidante. As hortaliças testadas podem ser vistas como fontes dietéticas de antioxidantes que podem trazer benefícios à saúde, portanto o seu consumo deve ser estimulado.This study was carried out to determine the antioxidant capacity of 15 vegetables commonly consumed in Recife - PE, Brazil. Methanol extracts were screened for their antioxidant activity using two tests: DPPH free radical scavenging and beta-carotene/linoléico acid assay. All vegetables showed antioxidant properties however the action was differentiated among the kinds of vegetables. The methanol extracts of collard greens, tomatoes, potatoes, cauliflowers, green cabbage, spinach and lettuce "crespa" had the

  10. Brote del virus ISA: crisis ambiental y capacidad de la institucionalidad ambiental para manejar el conflicto

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    Beatriz Bustos

    2012-09-01

    Full Text Available La industria salmonera chilena vivió recientemente una crisis de magnitud a partir de la aparición del virus ISA. El artículo examina esta situación, concentrándose en el papel que desempeña la ciencia en las soluciones políticas propuestas, como caso para discutir la capacidad de los mecanismos de gobernanza ambiental neoliberal para solucionar crisis ambientales y económicas. La pregunta que guía el trabajo es: ¿cuál fue el rol de la ciencia en la política ambiental para la industria? El argumento promovido es que la crisis representa un momento de reestructuración de la relación sociedad-naturaleza, en el cual se redefinieron mecanismos de propiedad, control y acceso a recursos naturales, pero en el que, pese al discurso neoliberal de confianza en los expertos y la ciencia como elementos de toma de decisiones, la información científica tuvo escasa relevancia.The Chilean salmon industry recently experienced a crisis due to an outbreak of the ISA virus. The article examines the crisis focusing on the role of science in the policy solutions proposed, to discuss the real capacity of neoliberal environmental governance mechanisms to solve environmental and economic crisis. The question guiding this research is, which was the role of science in environmental policy createdfor the salmon industry? The argument is that the crisis represents a reestructuring of the relationship between society and nature through the redefinition of property rights, control and access to natural resources, but in which, in spite of a neoliberal discourse of trust in experts and science as elements of decision making, scientific information had little relevance.

  11. Capacidad portante de pilotes empotrados en rocas considerando su aporte a fricción

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    Gilberto Quevedo

    Full Text Available Este artículo tiene como objetivo mostrar el estudio realizado de diferentes teorías existentes para considerar el aporte a fricción de pilotes empotrado en roca. Para ello se resume inicialmente los criterios considerados en dichas teorías y los intervalos de los coeficientes que las mismas consideran para la aplicación de sus expresiones básicas. Los resultados de este análisis teórico fueron aplicados en la solución de las cimentaciones sobre pilote de un hotel y su marina construido en la playa de Varadero, Cuba. La zona de estudio presentaba una alta complejidad ingeniero geológica, con una estratificación muy variables y propiedades de los suelos y las rocas de la misma igualmente variable, destacándose la presencia de un estrato de calcarenita, que aparece a una profundidad variable y con una calidad desde buena hasta muy mala, donde siempre se empotraron los pilotes. Para la obtención de la capacidad portante de muchos de los pilotes, fue necesario tomar en cuenta el aporte a fricción en la roca, validándose las teorías existente a partir de la realización de pruebas de carga in-situ, combinadas con el empleo de los modelos teóricos, llegando a establecer los valores de los coeficientes que las mismas utilizan para las condiciones del caso de estudio. A partir de todo ello fue que se pudo dar solución a las cimentaciones sobre pilotes del caso de estudio, la comprendía más de 2000 pilotes hincados.

  12. Capacidade antioxidante e qualidade pós-colheita de abacate 'Fuerte'

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    Rogério Lopes Vieites

    2012-06-01

    Full Text Available A capacidade antioxidante e a qualidade pós-colheita do abacate 'Fuerte' foram avaliadas. Os frutos foram mantidos sob temperatura ambiente (24 ± 1 ºC e sob refrigeração em 10 ± 1 ºC e 90±5% UR e avaliados durante 15 dias. Determinaram-se a perda de massa e a taxa respiratória. As características físico-químicas avaliadas foram acidez total titulável (AT, sólidos solúveis (SS, ratio, pH, firmeza, atividade da enzima polifenoloxidase (PPO, cor (L, a* e b*, fenólicos totais e atividade antioxidante (AA por DPPH·. Nas duas condições de armazenamento, o pico respiratório ocorreu no 9º dia.Os frutos mantidos sob temperatura refrigerada apresentaram menor perda de massa e maior firmeza em relação àqueles em temperatura ambiente. O comportamento respiratório refletiu na redução dos valores de AT e no conteúdo de SS que diminuíram a partir do pico de respiração. Os valores de pH aumentaram como consequência da diminuição da AT. Os valores de luminosidade mantiveram-se elevados, observando-se diminuição do componente de cor verde na polpa com o armazenamento. A atividade da PPO diminuiu com o armazenamento. Os valores de AA variaram de 17,6 a 68,7%. O conteúdo de fenólicos totais diminuiu após o pico respiratório, e valores crescentes de AA foram observados mesmo após o 9º dia.

  13. Capacidad entomocida de cepas nativas de Beauveria sp. sobre Schistocerca piceifrons peruviana (Lynch Arribalzaga, 1903

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    Nicolaza Pariona

    2013-04-01

    Full Text Available Cuatro cepas de Beauveria sp. (ABvPr11, ABvPr8, ABvPr3 y ABvSr4, fueron aisladas y caracterizadas de ejemplares de la langosta Schistocerca piceifrons peruviana procedentes de la Provincia de Huamanga del Departamento de Ayacucho. La capacidad entomocida de las 4 cepas fue evaluada en la langosta Schistocerca piceifrons peruviana. Los resultados muestran que todas las cepas, en soluciones de 108 conidias/mL, producen un 100% de mortalidad. El tiempo que se necesitó para eliminar el 100% de las langostas, para las cepas ABvPr11, ABvPr8, ABvSr4 y ABvPr3 fue de 12, 14 y 16 días respectivamente. Al décimo día se observó diferencias significativas respecto a la mortalidad, entre la cepa ABvPr11(90% y la cepas ABvSr4(74%, ABvPr8(72% y ABvPr3(64.6%. Posteriormente se determinó el tiempo de letalidad al 50% (TL50 de la población de langostas, con un intervalo de 8,38 a 9,16 días y el tiempo de letalidad al 80% (TL80 fue de 9,6 a 11,5 días. La cepa ABvPr11 presentó la mayor actividad entomocida para el control de Schistocerca piceifrons peruviana L.A.

  14. La capacidad de atención y el consumo transmedia

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    Germán Llorca Abad

    2015-02-01

    Full Text Available Los relatos audiovisuales se encuentran inmersos en un profundo proceso de transformación. Las fórmulas narrativas convencionales se enfrentan al desafío (oportunidad de lo transmediático. El presente artículo explora algunas claves de esta situación desde la perspectiva de la producción de contenidos, en un contexto de saturación comunicativa. El usuario de la comunicación dispone de un recurso muy escaso: su capacidad de atención. Lo audiovisual deberá afrontar esta dificultad a la hora de reinventarse. En un momento de abundancia de contenidos y de escaso tiempo para consumirlos, captar la atención del usuario será crucial para asegurar el éxito de una producción. Audio-visual transmedia content and new users’ behaviour Abstract Audiovisual storytelling is undergoing a deep process of change. The conventional narrative formulas have been challenged (have been given an opportunity by transmedia. This article explores some key aspects of this situation from the perspective of content production in a communicative context of saturation. The users of communication have a very scarce resource: their attention span. Audio-visual productions will have to face this difficulty to be reborn. In a time of saturation and the scarcity of time, being able to capture the user’s attention will be crucial for the success of a production. Keywords: Attention, transmedia, audiovisual, story, storytelling.

  15. ESTUDO DA SELETIVIDADE CAPACIDADE EM SISTEMAS SÓLIDO-GÁS

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    A. M. SOUZA

    1997-12-01

    Full Text Available A solubilidade de compostos pesados em fase gasosa contendo um componente supercrítico (equilíbrio sólido-gás foi analisada, adotando-se a equação de estado de Peng-Robinson para representar os sistemas sólido-gás estudados. A modelagem foi aplicada para vários sistemas binários (monossólido/monossolvente e multissólido/multissolvente. Para cada sistema, fez-se a estimação dos parâmetros pertinentes, os parâmetros de interação binária, obtidos por regressão não linear a partir dos dados experimentais de equilíbrio sólido-gás correspondentes. Tendo como base os dados binários, foi realizada uma análise de seletividade/ capacidade de sistemas do tipo 2 sólidos-1solvente, comparando-os com dados experimentais, e fez-se a comparação com os sistemas ternários experimentais.The solubility of heavy compounds in gaseous phase containing a supercritical component (solid-gas equilibrium was analised. It was adopted the state equation of Peng-Robinson, to represent the solid-gas systems considered. The model was applied to several cases ranging from binary systems (mono-solid/mono-solvent to multi-solid/multi-solvent systems. For each system, it was done the estimation of pertinent parameters, the binary interaction parameters, obtained by non-linear regression from experimental data of correspondent solid-gas equilibrium. Using the results obtained from binary systems, predictions of selectivity/capacity for ternary systems like 2 solids-1 solvent were accomplished, and then a comparison with experimental data of ternary systems was achieved.

  16. Controlled chaos: three-dimensional kinematics, fiber histochemistry, and muscle contractile dynamics of autotomized lizard tails.

    Science.gov (United States)

    Higham, Timothy E; Lipsett, Kathryn R; Syme, Douglas A; Russell, Anthony P

    2013-01-01

    The ability to shed an appendage occurs in both vertebrates and invertebrates, often as a tactic to avoid predation. The tails of lizards, unlike most autotomized body parts of animals, exhibit complex and vigorous movements once disconnected from the body. Despite the near ubiquity of autotomy across groups of lizards and the fact that this is an extraordinary event involving the self-severing of the spinal cord, our understanding of why and how tails move as they do following autotomy is sparse. We herein explore the histochemistry and physiology of the tail muscles of the leopard gecko (Eublepharis macularius), a species that exhibits vigorous and variable tail movements following autotomy. To confirm that the previously studied tail movements of this species are generally representative of geckos and therefore suitable for in-depth muscle studies, we quantified the three-dimensional kinematics of autotomized tails in three additional species. The movements of the tails of all species were generally similar and included jumps, flips, and swings. Our preliminary analyses suggest that some species of gecko exhibit short but high-frequency movements, whereas others exhibit larger-amplitude but lower-frequency movements. We then compared the ATPase and oxidative capacity of muscle fibers and contractile dynamics of isolated muscle bundles from original tails, muscle from regenerate tails, and fast fibers from an upper limb muscle (iliofibularis) of the leopard gecko. Histochemical analysis revealed that more than 90% of the fibers in original and regenerate caudal muscles had high ATPase but possessed a superficial layer of fibers with low ATPase and high oxidative capacity. We found that contraction kinetics, isometric force, work, power output, and the oscillation frequency at which maximum power was generated were lowest in the original tail, followed by the regenerate tail and then the fast fibers of the iliofibularis. Muscle from the original tail exhibited

  17. Global and Regional Left Ventricular Contractile Impairment In Patients With Wolff-Parkinson-White Syndrome

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    Sony Jacob

    2009-07-01

    Full Text Available Background: To assess regional systolic function and global contractile function in patients with WPW Syndrome.Method: Eleven cases with manifest Wolff-Parkinson-White (WPW syndrome in sinus rhythm were compared to 11 age matched controls. 2D strain analysis was performed and peak segmental radial strain (pRS values obtained from basal ventricular parasternal short-axis images (70 ± 5 frames/sec using a dedicated software package. Heterogeneity of radial strain pattern in six circumferential basal left ventricular segments was measured in terms of standard deviations of peak RS (SDpRS or range (difference between maximum and minimum peak RS i.e. RangepRS. Spectral Doppler (continuous wave measurements were acquired through the left ventricular outflow tract to determine Pre Ejection Period (PEP, Left Ventricular Ejection Time (LVET and measures of left ventricular systolic performance. Results: LV segmental radial strain was profoundly heterogeneous in WPW cases in contrast to fairly homogenous strain pattern in normal subjects. Wide SDpRS values 17.5 ± 8.9 vs 3.3 ± 1.4, p<0.001 and RangepRS 42.7 ± 20.8 vs.8.5 ± 3.6 , p<0.001 were observed among WPW and healthy subjects respectively. PEP (132.4 ± 14.7 vs 4.7 ± 0.5ms, p<0.001 and corrected PEP (76.1 ± 8.0 vs 2.7 ± 0.4ms, p<0.001 were significantly longer in WPW patients compared to controls. The PEP/LVET ratio was also significantly greater in WPW cohort (0.49 ± 0.04 vs. 0.28 ± 0.05, p <0.001 suggesting global systolic dysfunction. Conclusion: Patients with manifest preexcitation (predominantly those with right-sided pathways have regional and global contractile dysfunction resulting from aberrant impulse propagation inherent to the preexcited state.

  18. Dietary fat influences the expression of contractile and metabolic genes in rat skeletal muscle.

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    Wataru Mizunoya

    Full Text Available Dietary fat plays a major role in obesity, lipid metabolism, and cardiovascular diseases. To determine whether the intake of different types of dietary fats affect the muscle fiber types that govern the metabolic and contractile properties of the skeletal muscle, we fed male Wistar rats with a 15% fat diet derived from different fat sources. Diets composed of soybean oil (n-6 polyunsaturated fatty acids (PUFA-rich, fish oil (n-3 PUFA-rich, or lard (low in PUFAs were administered to the rats for 4 weeks. Myosin heavy chain (MyHC isoforms were used as biomarkers to delineate the skeletal muscle fiber types. Compared with soybean oil intake, fish oil intake showed significantly lower levels of the fast-type MyHC2B and higher levels of the intermediate-type MyHC2X composition in the extensor digitorum longus (EDL muscle, which is a fast-type dominant muscle. Concomitantly, MyHC2X mRNA levels in fish oil-fed rats were significantly higher than those observed in the soybean oil-fed rats. The MyHC isoform composition in the lard-fed rats was an intermediate between that of the fish oil and soybean oil-fed rats. Mitochondrial uncoupling protein 3, pyruvate dehydrogenase kinase 4, and porin mRNA showed significantly upregulated levels in the EDL of fish oil-fed rats compared to those observed in soybean oil-fed and lard-fed rats, implying an activation of oxidative metabolism. In contrast, no changes in the composition of MyHC isoforms was observed in the soleus muscle, which is a slow-type dominant muscle. Fatty acid composition in the serum and the muscle was significantly influenced by the type of dietary fat consumed. In conclusion, dietary fat affects the expression of genes related to the contractile and metabolic properties in the fast-type dominant skeletal muscle, where the activation of oxidative metabolism is more pronounced after fish oil intake than that after soybean oil intake.

  19. Efecto de las estrategias competitivas y los recursos y capacidades orientados al mercado sobre el crecimiento de las organizaciones

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    Carmen Berenice Ynzunza Cortés

    2013-01-01

    Full Text Available Este estudio analiza las relaciones entre las fuerzas de mercado, las estrategias competitivas, los recursos y capacidades orientados al mercado, así como el desempeño organizacional. La investigación se realizó en Pyme del sector industrial del estado de Querétaro, con un muestreo de conveniencia no probabilístico; asimismo, se diseñó un modelo estructural para probar las relaciones entre las variables, las cuales se analizaron con el software AMOS. El tamaño de muestra alcanzado fue de 116 y la recopilación de información se hizo mediante entrevistas. Las fuerzas de mercado, la estrategia competitiva y la orientación a mercado fueron medidas con las escalas de Kohly y Javorsky (1990, Segev (1987 y Narver y Slater (1990. Los ítems para el desempeño organizacional y los recursos de tecnología e innovación fueron diseñados. Los hallazgos prueban que las fuerzas de mercado tienen un impacto grande en la estrategia competitiva, el cual no es significativo sobre los recursos y capacidades, y es negativo respecto al desempeño, medido por el crecimiento organizacional. El efecto de la estrategia competitiva ha sido significativo sobre los recursos y capacidades de orientación a mercado, tecnología e innovación y no significativo respecto al desempeño. Estos recursos y capacidades influyen de manera significativa en el desempeño organizacional. Los resultados de este estudio enfatizan la implementación de estrategias prospectoras y analizadoras, que crean recursos y capacidades que den valor, con beneficios económicos para las empresas, así como los de orientación a mercado, tecnología e innovación. Estos hallazgos son consistentes con los encontrados en otras investigaciones realizadas en otros países.

  20. Abnormal glucose metabolism is associated with reduced left ventricular contractile reserve and exercise intolerance in patients with chronic heart failure

    DEFF Research Database (Denmark)

    Egstrup, M; Kistorp, C N; Schou, M

    2013-01-01

    AIMS: To investigate the associations between glucose metabolism, left ventricular (LV) contractile reserve, and exercise capacity in patients with chronic systolic heart failure (HF). METHODS AND RESULTS: From an outpatient HF clinic, 161 patients with systolic HF were included (mean age 70 ± 10...... or new DM. All patients completed low-dose dobutamine echocardiography (LDDE) and 154 patients a 6-min walking distance test (6MWD). Compared with patients with NGT, patients with known DM had lower resting LVEF (33.4 vs. 39.1%, P ... in LVEF could be observed in all glycemic groups (mean 8.2% absolute increase), but the contractile reserve was lower in patients with known DM (-5.4%, P = 0.001) and new DM (-3.5%, P = 0.035) compared to patients with NGT. 6MWD was lower in known DM (349 m) and new DM (379 m) compared with NGT (467 m) (P...

  1. Integrated Analysis of Contractile Kinetics, Force Generation, and Electrical Activity in Single Human Stem Cell-Derived Cardiomyocytes

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    Jan David Kijlstra

    2015-12-01

    Full Text Available The quantitative analysis of cardiomyocyte function is essential for stem cell-based approaches for the in vitro study of human cardiac physiology and pathophysiology. We present a method to comprehensively assess the function of single human pluripotent stem cell-derived cardiomyocyte (hPSC-CMs through simultaneous quantitative analysis of contraction kinetics, force generation, and electrical activity. We demonstrate that statistical analysis of movies of contracting hPSC-CMs can be used to quantify changes in cellular morphology over time and compute contractile kinetics. Using a biomechanical model that incorporates substrate stiffness, we calculate cardiomyocyte force generation at single-cell resolution and validate this approach with conventional traction force microscopy. The addition of fluorescent calcium indicators or membrane potential dyes allows the simultaneous analysis of contractility and calcium handling or action potential morphology. Accordingly, our approach has the potential for broad application in the study of cardiac disease, drug discovery, and cardiotoxicity screening.

  2. Influencia de la capacidad de absorción sobre la innovación: un análisis empírico en las mipymes colombianas

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    Carlos Hernán González-Campo

    2014-07-01

    Full Text Available Este artículo analiza la capacidad de absorción como un constructo multidimensional y tiene como objetivo determinar la presencia de dicha capacidad en las mipymes colombianas y su relación con la innovación, siendo este uno de los primeros estudios en este campo realizados en Colombia. Partiendo de una muestra de 403 mipymes colombianas, se efectúa un análisis de conglomerados bietápico que permite probar que la capacidad de absorción no es un determinante de la innovación en estas empresas, y permite demostrar que la capacidad de absorción se desarrolla principalmente en las pequeñas empresas colombianas y los procesos de innovación están determinados por las estrategias competitivas asumidas por cada tipo de empresas.

  3. CAMBIO Y GENERACIÓN de capacidades competitivas Un estudio en las empresas medianas y grandes de confecciones del eje cafetero

    Directory of Open Access Journals (Sweden)

    Paula Andrea Cruz Mejía

    2006-07-01

    Full Text Available Este artículo pretende constatar las relaciones entre el cambio organizacional y las capacidades organizativas críticas para la competitividad, relaciones que la literatura especializada define desde un enfoque teórico. Se seleccionaron seis capacidades críticas: flexibilidad, gestión del capital humano, liderazgo, aprendizaje organizacional, relaciones con el cliente y claridad estratégica. En este trabajo estas relaciones se analizan desde la teoría de recursos y capacidades. La muestra se cotejo aplicando el cuestionario propuesto a 35 directivos de siete empresas medianas y grandes del sector confecciones del Eje Cafetero; posteriormente se realizó una entrevista con cinco expertos del sector para analizar los hallazgos. Se encontró evidencia empírica para afirmar que el cambio organizacional incide en el desarrollo de las capacidades críticas competitivas.

  4. Thomas Armstrong (2012: El poder de la neurodiversidad. Las extraordinarias capacidades que se ocultan tras el autismo, la hiperactividad, la dislexia y otras diferencias cerebrales. Barcelona: Espasa Libros.

    Directory of Open Access Journals (Sweden)

    Ángela María Lopera Murcia

    2017-06-01

    Full Text Available Reseña de la obra 'El poder de la neurodiversidad. Las extraordinarias capacidades que se ocultan tras el autismo, la hiperactividad, la dislexia y otras diferencias cerebrales' (2012 de Thomas Armstrong.

  5. Thomas Armstrong (2012): El poder de la neurodiversidad. Las extraordinarias capacidades que se ocultan tras el autismo, la hiperactividad, la dislexia y otras diferencias cerebrales. Barcelona: Espasa Libros.

    OpenAIRE

    Ángela María Lopera Murcia

    2017-01-01

    Reseña de la obra 'El poder de la neurodiversidad. Las extraordinarias capacidades que se ocultan tras el autismo, la hiperactividad, la dislexia y otras diferencias cerebrales' (2012) de Thomas Armstrong.

  6. Permanent Distal Occlusion of Middle Cerebral Artery in Rat Causes Local Increased ETB, 5-HT1B and AT1 Receptor-Mediated Contractility Downstream of Occlusion

    DEFF Research Database (Denmark)

    Rasmussen, Marianne N P; Hornbak, Malene; Larsen, Stine S

    2013-01-01

    Background/Aims: In response to experimental stroke, a characteristic functional and expressional upregulation of contractile G-protein-coupled receptors has been uncovered in the affected cerebral vasculature; however, the mechanism initiating this phenomenon remains unknown. Methods: Using...... a model of permanent distal occlusion of rat middle cerebral arteries, we investigated whether there was a regional difference in receptor-mediated contractility of segments located upstream and downstream of the occlusion site. The contractile response to endothelin, angiotensin and 5-hydroxytryptamine...... receptor stimulation was studied by sensitive wire myograph. Results: Only downstream segments exhibited an augmented contractile response to stimulation with each of the three ligands, with the response towards sarafotoxin 6c being especially augmented compared to sham, upstream and contralateral controls...

  7. Effect of chronic and acute cigarette smoking on the pharyngo-upper oesophageal sphincter contractile reflex and reflexive pharyngeal swallow

    OpenAIRE

    Dua, K; Bardan, E; Ren, J; Sui, Z; Shaker, R

    1998-01-01

    Background—Cigarette smoking is known to affect adversely the defence mechanisms against gastro-oesophageal reflux. The effect of smoking on the supraoesophageal reflexes that prevent aspiration of gastric contents has not been previously studied. 
Aims—To elucidate the effect of cigarette smoking on two of the supraoesophageal reflexes: the pharyngo-upper oesophageal sphincter (UOS) contractile reflex; and the reflexive pharyngeal swallow. 
Methods—Ten chronic smokers and 10 non-...

  8. Differential Kolaviron Attenuated Contractile Responses to Agonists on Isolated Rabbit Aorta in Na+-K+ Pump Blockade.

    Science.gov (United States)

    Uche, O K; Ofeimun, J O

    2017-12-30

    The mechanism of kolaviron-induced vascular smooth muscles (VSMs) responses has not been fullycharacterised. The present study investigated the effect and mode of action of kolaviron a biflavanoid-complex and majorcomponent of Garcinia Kola-fraction on differential contractile responses to agonists-[phenylephrine (PHE) and histamine(HIST)] on VSMs of rabbit isolated aortic rings in K+-free physiological salt solution (KFPSS). Cumulative concentrationresponses to PHE and HIST were examined on 2 mm ring segments of the thoracic aortae which were suspended in 20 mlorgan baths containing physiological salt solution (PSS) for measurement of isometric contractions, at 370C and pH 7.4. Themedium was bubbled with 95% O2, 5% CO2, and rings were given an initial load of 1g. Cumulative contractile responses tothe agonists were studied in normal PSS (control) and following 30 minutes exposure to K+-free PSS and/or 800µg/mLkolaviron. Contractile responses were expressed as percentage of 80 mM K+ contractions in normal PSS. Maximalcontractions (Emax) induced by PHE and HIST compared with high K+ contraction in the various preparations weredifferentially altered following exposure to K+-free or 800µg/mL kolaviron in both intact (+E) and endotheliumdenuded (-E) rings. Based on the efficacy (Emax) and potency (EC50) values for the dose-response curves of the agonists, it isconcluded that enhanced differential contractile responses elicited by agonists in K+-free PSS were significantly attenuatedby kolaviron concentration-dependently. This observation probably suggests the existence of another pathway of kolavironmode of action in vascular smooth muscle reactivity.

  9. Moderate ethanol administration accentuates cardiomyocyte contractile dysfunction and mitochondrial injury in high fat diet-induced obesity.

    Science.gov (United States)

    Yuan, Fang; Lei, Yonghong; Wang, Qiurong; Esberg, Lucy B; Huang, Zaixing; Scott, Glenda I; Li, Xue; Ren, Jun

    2015-03-18

    Light to moderate drinking confers cardioprotection although it remains unclear with regards to the role of moderate drinking on cardiac function in obesity. This study was designed to examine the impact of moderate ethanol intake on myocardial function in high fat diet intake-induced obesity and the mechanism(s) involved with a focus on mitochondrial integrity. C57BL/6 mice were fed low or high fat diet for 16 weeks prior to ethanol challenge (1g/kg/d for 3 days). Cardiac contractile function, intracellular Ca(2+) homeostasis, myocardial histology, and mitochondrial integrity [aconitase activity and the mitochondrial proteins SOD1, UCP-2 and PPARγ coactivator 1α (PGC-1α)] were assessed 24h after the final ethanol challenge. Fat diet intake compromised cardiomyocyte contractile and intracellular Ca(2+) properties (depressed peak shortening and maximal velocities of shortening/relengthening, prolonged duration of relengthening, dampened intracellular Ca(2+) rise and clearance without affecting duration of shortening). Although moderate ethanol challenge failed to alter cardiomyocyte mechanical property under low fat diet intake, it accentuated high fat diet intake-induced changes in cardiomyocyte contractile function and intracellular Ca(2+) handling. Moderate ethanol challenge failed to affect fat diet intake-induced cardiac hypertrophy as evidenced by H&E staining. High fat diet intake reduced myocardial aconitase activity, downregulated levels of mitochondrial protein UCP-2, PGC-1α, SOD1 and interrupted intracellular Ca(2+) regulatory proteins, the effect of which was augmented by moderate ethanol challenge. Neither high fat diet intake nor moderate ethanol challenge affected protein or mRNA levels as well as phosphorylation of Akt and GSK3β in mouse hearts. Taken together, our data revealed that moderate ethanol challenge accentuated high fat diet-induced cardiac contractile and intracellular Ca(2+) anomalies as well as mitochondrial injury. Copyright

  10. Altered contractile responses of arteries from spontaneously hypertensive rat: The role of endogenous mediators and membrane depolarization

    Czech Academy of Sciences Publication Activity Database

    Bencze, Michal; Behuliak, Michal; Vavřínová, Anna; Zicha, Josef

    2016-01-01

    Roč. 166, Dec 1 (2016), s. 46-53 ISSN 0024-3205 R&D Projects: GA ČR(CZ) GAP304/12/0259; GA MZd(CZ) NV15-25396A Institutional support: RVO:67985823 Keywords : femoral artery * SHR * vascular contractility * adrenergic contraction * tyramine * propranolol * neuropeptide Y Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 2.936, year: 2016

  11. Stochastic Ratcheting on a Funneled Energy Landscape Is Necessary for Highly Efficient Contractility of Actomyosin Force Dipoles

    Science.gov (United States)

    Komianos, James E.; Papoian, Garegin A.

    2018-04-01

    Current understanding of how contractility emerges in disordered actomyosin networks of nonmuscle cells is still largely based on the intuition derived from earlier works on muscle contractility. In addition, in disordered networks, passive cross-linkers have been hypothesized to percolate force chains in the network, hence, establishing large-scale connectivity between local contractile clusters. This view, however, largely overlooks the free energy of cross-linker binding at the microscale, which, even in the absence of active fluctuations, provides a thermodynamic drive towards highly overlapping filamentous states. In this work, we use stochastic simulations and mean-field theory to shed light on the dynamics of a single actomyosin force dipole—a pair of antiparallel actin filaments interacting with active myosin II motors and passive cross-linkers. We first show that while passive cross-linking without motor activity can produce significant contraction between a pair of actin filaments, driven by thermodynamic favorability of cross-linker binding, a sharp onset of kinetic arrest exists at large cross-link binding energies, greatly diminishing the effectiveness of this contractility mechanism. Then, when considering an active force dipole containing nonmuscle myosin II, we find that cross-linkers can also serve as a structural ratchet when the motor dissociates stochastically from the actin filaments, resulting in significant force amplification when both molecules are present. Our results provide predictions of how actomyosin force dipoles behave at the molecular level with respect to filament boundary conditions, passive cross-linking, and motor activity, which can explicitly be tested using an optical trapping experiment.

  12. Cardiac-specific catalase overexpression rescues anthrax lethal toxin-induced cardiac contractile dysfunction: role of oxidative stress and autophagy

    OpenAIRE

    Kandadi, Machender R; Yu, Xuejun; Frankel, Arthur E; Ren, Jun

    2012-01-01

    Abstract Background Lethal and edema toxins secreted by Bacillus anthracis during anthrax infection were found to incite serious cardiovascular complications. However, the underlying mechanisms in anthrax lethal toxin-induced cardiac anomalies remain unknown. This study was designed to evaluate the impact of antioxidant enzyme catalase in anthrax lethal toxin-induced cardiomyocyte contractile dysfunction. Methods Wild type (WT) and cardiac-specific catalase overexpression mice were challenged...

  13. The neuromechanical functional contractile properties of the thigh muscles measured using tensiomyography in male athletes and non-athletes

    Directory of Open Access Journals (Sweden)

    Toskić Lazar

    2016-01-01

    Full Text Available Involuntary neuromechanical muscle contractile properties, especially of the extensor muscles and knee joint flexors as the largest muscle groups of the caudal part of the body, play an important role in both everyday movement and sport. Based on these data we can obtain important information on the functional properties of muscles. The basic means of evaluation of the functional involuntary neuromechanical muscles contractile properties is the non-invasive tensiomyographic method (TMG. The aim of this study was to determine the differences between the involuntary neuromechanical contractile properties of the thigh muscles measured using the TMG method on a sample of male athletes and non-athletes. The sample of participants was made up of 17 athletes and 10 non-athletes. By applying the multivariate analysis of variance (MANOVA and the t-test, we achieved results which indicate that of the overall 30 variables, a difference was determined among 13 of them. Most of the differences were determined for the extensor muscles of the right knee, especially of the rectus femoris muscle. It was also shown that in addition to the main knee joint extensor muscle (rectus femoris the main knee joint flexor muscle (biceps femoris also takes part in the definition of the difference between athletes and non-athletes. The results have shown that the following variables: contraction time (Tc and delay contraction time (Td are the functional parameters for which the highest difference between athletes and non-athletes were determined (from t = -2.284, p < 0.05 for the vastus lateralis of the right leg to t = -4.018, p < 0.01 for the rectus femoris of the left leg. These results have shown that it is possible to determine the differences in the functional involuntary neuromechanical contractile properties of the thigh muscles among trained and untrained individuals using the tensiomyographic method, but at the same time indicated that these differences were very

  14. Stochastic Ratcheting on a Funneled Energy Landscape Is Necessary for Highly Efficient Contractility of Actomyosin Force Dipoles

    Directory of Open Access Journals (Sweden)

    James E. Komianos

    2018-04-01

    Full Text Available Current understanding of how contractility emerges in disordered actomyosin networks of nonmuscle cells is still largely based on the intuition derived from earlier works on muscle contractility. In addition, in disordered networks, passive cross-linkers have been hypothesized to percolate force chains in the network, hence, establishing large-scale connectivity between local contractile clusters. This view, however, largely overlooks the free energy of cross-linker binding at the microscale, which, even in the absence of active fluctuations, provides a thermodynamic drive towards highly overlapping filamentous states. In this work, we use stochastic simulations and mean-field theory to shed light on the dynamics of a single actomyosin force dipole—a pair of antiparallel actin filaments interacting with active myosin II motors and passive cross-linkers. We first show that while passive cross-linking without motor activity can produce significant contraction between a pair of actin filaments, driven by thermodynamic favorability of cross-linker binding, a sharp onset of kinetic arrest exists at large cross-link binding energies, greatly diminishing the effectiveness of this contractility mechanism. Then, when considering an active force dipole containing nonmuscle myosin II, we find that cross-linkers can also serve as a structural ratchet when the motor dissociates stochastically from the actin filaments, resulting in significant force amplification when both molecules are present. Our results provide predictions of how actomyosin force dipoles behave at the molecular level with respect to filament boundary conditions, passive cross-linking, and motor activity, which can explicitly be tested using an optical trapping experiment.

  15. Contribution of contractile state of the non-infarcted area to global ventricular performance after acute myocardial infarction

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Yasuda, Tsunehiro; Gold, H.K.; Leinbach, R.C.; Boucher, C.A.; McKusick, K.A.; Strauss, H.W.

    1986-01-01

    To evaluate the regional contractile state of the non-infarcted zone and to determine the contribution of this area to left ventricular (LV) performance, 112 patients (42 anterior and 70 inferior infarction) with their first acute myocardial infarction were investigated by radionuclide ventriculography at admission and 10 days after admission. Wall motion at the non-infarcted area was defined as hyperkinetic, normal, or hypokinetic, if radial chord shortening had above normal, normal, or below normal values, respectively, by quantitative wall motion analysis. Hyperkinetic, normal, and hypokinetic wall motion of the non-infarcted area were observed in three (7 %), 12 (29 %), and 27 (64 %) patients in anterior infarction and 14 (20 %), 28 (40 %), and 28 (40 %) in inferior infarction, respectively. In the patients with hypokinetic wall motion at the non-infarcted area, the infarct involved more than 30 % of the left ventricle manifesting akinetic contractile segment (ACS), radial chord shortening in the infarcted area was severely depressed, and the incidence of multi-vessel involvement was higher compared with those with hyperkinetic or normal wall motion. In serial measurements, radial chord shortening in the infarcted and non-infarcted area, percent ACS, left ventricular ejection fraction, and left ventricular end-diastolic volume index did not change significantly from acute to follow-up study in any group. In conclusion, our data indicated that the non-infarcted area following acute infarction had various contractile states and these conditions were determined primarily by the severity and extent of infarct and underlying coronary artery disease. Furthermore, the contractile state of the non-infarcted area has a supplemental role in determination of LV function following acute infarction. (author)

  16. Inhibition of CYP2E1 attenuates chronic alcohol intake-induced myocardial contractile dysfunction and apoptosis.

    Science.gov (United States)

    Zhang, Rong-Huai; Gao, Jian-Yuan; Guo, Hai-Tao; Scott, Glenda I; Eason, Anna R; Wang, Xiao-Ming; Ren, Jun

    2013-01-01

    Alcohol intake is associated with myocardial contractile dysfunction and apoptosis although the precise mechanism is unclear. This study was designed to examine the effect of the cytochrome P450 enzyme CYP2E1 inhibition on ethanol-induced cardiac dysfunction. Adult male mice were fed a 4% ethanol liquid or pair-fed control diet for 6weeks. Following 2weeks of diet feeding, a cohort of mice started to receive the CYP2E1 inhibitor diallyl sulfide (100mg/kg/d, i.p.) for the remaining feeding duration. Cardiac function was assessed using echocardiographic and IonOptix systems. Western blot analysis was used to evaluate CYP2E1, heme oxygenase-1 (HO-1), iNOS, the intracellular Ca(2+) regulatory proteins sarco(endo)plasmic reticulum Ca(2+)-ATPase, Na(+)Ca(2+) exchanger and phospholamban, pro-apoptotic protein cleaved caspase-3, Bax, c-Jun-NH(2)-terminal kinase (JNK) and apoptosis signal-regulating kinase (ASK-1). Ethanol led to elevated levels of CYP2E1, iNOS and phospholamban, decreased levels of HO-1 and Na(+)Ca(2+) exchanger, cardiac contractile and intracellular Ca(2+) defects, cardiac fibrosis, overt O(2)(-) production, and apoptosis accompanied with increased phosphorylation of JNK and ASK-1, the effects were significantly attenuated or ablated by diallyl sulfide. Inhibitors of JNK and ASK-1 but not HO-1 inducer or iNOS inhibitor obliterated ethanol-induced cardiomyocyte contractile dysfunction, substantiating a role for JNK and ASK-1 signaling in ethanol-induced myocardial injury. Taken together, these findings suggest that ethanol metabolism through CYP2E1 may contribute to the pathogenesis of alcoholic cardiomyopathy including myocardial contractile dysfunction, oxidative stress and apoptosis, possibly through activation of JNK and ASK-1 signaling. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Enhancement of contractile force generation of artificial skeletal muscle tissues by mild and transient heat treatment.

    Science.gov (United States)

    Sato, Masanori; Ikeda, Kazushi; Kanno, Shota; Ito, Akira; Kawabe, Yoshinori; Kamihira, Masamichi

    2014-01-01

    Artificial skeletal muscle tissues composed of cells are expected to be used for applications of regenerative medicine and drug screening. Generally, however, the physical forces generated by tissue-engineered skeletal muscle are lower than those of skeletal muscle tissues found in the body. Local hyperthermia is used for many diseases including muscle injuries. It was recently reported that mild heat treatment improved skeletal muscle functions. In this study, we investigated the effects of mild heat treatment on the tissue-engineered skeletal muscle tissues in vitro. We used magnetite cationic liposomes to label C2C12 myoblast cells magnetically, and constructed densely packed artificial skeletal muscle tissues by using magnetic force. Cell culture at 39°C promoted the differentiation of myoblast cells into myotubes. Moreover, the mild and transient heat treatment improved the contractile properties of artificial skeletal muscle tissue constructs. These findings indicate that the culture method using heat treatment is a useful approach to enhance functions of artificial skeletal muscle tissue.

  18. Bidirectional Interplay between Vimentin Intermediate Filaments and Contractile Actin Stress Fibers.

    Science.gov (United States)

    Jiu, Yaming; Lehtimäki, Jaakko; Tojkander, Sari; Cheng, Fang; Jäälinoja, Harri; Liu, Xiaonan; Varjosalo, Markku; Eriksson, John E; Lappalainen, Pekka

    2015-06-16

    The actin cytoskeleton and cytoplasmic intermediate filaments contribute to cell migration and morphogenesis, but the interplay between these two central cytoskeletal elements has remained elusive. Here, we find that specific actin stress fiber structures, transverse arcs, interact with vimentin intermediate filaments and promote their retrograde flow. Consequently, myosin-II-containing arcs are important for perinuclear localization of the vimentin network in cells. The vimentin network reciprocally restricts retrograde movement of arcs and hence controls the width of flat lamellum at the leading edge of the cell. Depletion of plectin recapitulates the vimentin organization phenotype of arc-deficient cells without affecting the integrity of vimentin filaments or stress fibers, demonstrating that this cytoskeletal cross-linker is required for productive interactions between vimentin and arcs. Collectively, our results reveal that plectin-mediated interplay between contractile actomyosin arcs and vimentin intermediate filaments controls the localization and dynamics of these two cytoskeletal systems and is consequently important for cell morphogenesis. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  19. The Mitochondrial Calcium Uniporter Selectively Matches Metabolic Output to Acute Contractile Stress in the Heart

    Directory of Open Access Journals (Sweden)

    Jennifer Q. Kwong

    2015-07-01

    Full Text Available In the heart, augmented Ca2+ fluxing drives contractility and ATP generation through mitochondrial Ca2+ loading. Pathologic mitochondrial Ca2+ overload with ischemic injury triggers mitochondrial permeability transition pore (MPTP opening and cardiomyocyte death. Mitochondrial Ca2+ uptake is primarily mediated by the mitochondrial Ca2+ uniporter (MCU. Here, we generated mice with adult and cardiomyocyte-specific deletion of Mcu, which produced mitochondria refractory to acute Ca2+ uptake, with impaired ATP production, and inhibited MPTP opening upon acute Ca2+ challenge. Mice lacking Mcu in the adult heart were also protected from acute ischemia-reperfusion injury. However, resting/basal mitochondrial Ca2+ levels were normal in hearts of Mcu-deleted mice, and mitochondria lacking MCU eventually loaded with Ca2+ after stress stimulation. Indeed, Mcu-deleted mice were unable to immediately sprint on a treadmill unless warmed up for 30 min. Hence, MCU is a dedicated regulator of short-term mitochondrial Ca2+ loading underlying a “fight-or-flight” response that acutely matches cardiac workload with ATP production.

  20. [Effects of genistein on contractility of isolated right ventricular muscles in guinea pig].

    Science.gov (United States)

    Wu, Jin-xia; Li, Hong-fang; Liu, Chong-bin; Tian, Zhi-feng

    2008-11-01

    To study the effect of genistein (GEN) on contractility of isolated right ventricular muscles in guinea pig and its mechanisms. Isolated guinea pig ventricular muscles were suspended in organ baths containing K-H solution.After an equilibration period, the effect of GEN on contraction of myocardium was observed. GEN and isoprenaline hydrochloride had the positive inotropic effects on contractity of myocardium. Meanwhile, the effect of GEN (1-100 micromol x L(-1)) was in dose-dependent manner. Propranolol (1 micromol x L(-1)) and verapamil hydrochloride (0.5 micromol x L(-1)) attenuated the positive inotropic effect of isoprenaline hydrochloride (1 micromol x L(-1)), but did not change the effect of GEN (50 micromol x L(-1)). Further more, the enhancement of the contraction induced by elevation of extracellular Ca2+ concentration in ventricular muscles had no change after pretreatment with GEN (1.10 micromol x L(-1)). In addition,the positive inotropic effect of GEN was inhibited partially by tamoxifen (1 micromol x L(-1)) and SQ22536 (1 micromol x L(-1)), also, could be attenuated by bpV (1 micromol x L(-1)). GEN has the positive inotropic effect on guinea pig ventricular muscles, which is not related to the activation of beta adrenoceptor, Ca2+ channel on cell membrane,but may involve in cAMP of intracellular signal transduction and tyrosine kinase pathway.

  1. Simulation of the contractile response of cells on an array of micro-posts.

    LENUS (Irish Health Repository)

    McGarry, J P

    2009-09-13

    A bio-chemo-mechanical model has been used to predict the contractile responses of smooth cells on a bed of micro-posts. Predictions obtained for smooth muscle cells reveal that, by converging onto a single set of parameters, the model captures all of the following responses in a self-consistent manner: (i) the scaling of the force exerted by the cells with the number of posts; (ii) actin distributions within the cells, including the rings of actin around the micro-posts; (iii) the curvature of the cell boundaries between the posts; and (iv) the higher post forces towards the cell periphery. Similar correspondences between predictions and measurements have been demonstrated for fibroblasts and mesenchymal stem cells once the maximum stress exerted by the stress fibre bundles has been recalibrated. Consistent with measurements, the model predicts that the forces exerted by the cells will increase with both increasing post stiffness and cell area (or equivalently, post spacing). In conjunction with previous assessments, these findings suggest that this framework represents an important step towards a complete model for the coupled bio-chemo-mechanical responses of cells.

  2. Shortening actin filaments cause force generation in actomyosin network to change from contractile to extensile

    Science.gov (United States)

    Kumar, Nitin; Gardel, Margaret

    Motor proteins in conjunction with filamentous proteins convert biochemical energy into mechanical energy which serves a number of cellular processes including cell motility, force generation and intracellular cargo transport. In-vitro experiments suggest that the forces generated by kinesin motors on microtubule bundles are extensile in nature whereas myosin motors on actin filaments are contractile. It is not clear how qualitatively similar systems can show completely different behaviors in terms of the nature of force generation. In order to answer this question, we carry out in vitro experiments where we form quasi 2D filamentous actomyosin networks and vary the length of actin filaments by adding capping protein. We show that when filaments are much shorter than their typical persistence length (approximately 10 microns), the forces generated are extensile and we see active nematic defect propagation, as seen in the microtubule-kinesin system. Based on this observation, we claim that the rigidity of rods plays an important role in dictating the nature of force generation in such systems. In order to understand this transition, we selectively label individual filaments and find that longer filaments show considerable bending and buckling, making them difficult to slide and extend along their length.

  3. An Equatorial Contractile Mechanism Drives Cell Elongation but not Cell Division

    Science.gov (United States)

    Denker, Elsa; Bhattachan, Punit; Deng, Wei; Mathiesen, Birthe T.; Jiang, Di

    2014-01-01

    Cell shape changes and proliferation are two fundamental strategies for morphogenesis in animal development. During embryogenesis of the simple chordate Ciona intestinalis, elongation of individual notochord cells constitutes a crucial stage of notochord growth, which contributes to the establishment of the larval body plan. The mechanism of cell elongation is elusive. Here we show that although notochord cells do not divide, they use a cytokinesis-like actomyosin mechanism to drive cell elongation. The actomyosin network forming at the equator of each notochord cell includes phosphorylated myosin regulatory light chain, α-actinin, cofilin, tropomyosin, and talin. We demonstrate that cofilin and α-actinin are two crucial components for cell elongation. Cortical flow contributes to the assembly of the actomyosin ring. Similar to cytokinetic cells, membrane blebs that cause local contractions form at the basal cortex next to the equator and participate in force generation. We present a model in which the cooperation of equatorial actomyosin ring-based constriction and bleb-associated contractions at the basal cortex promotes cell elongation. Our results demonstrate that a cytokinesis-like contractile mechanism is co-opted in a completely different developmental scenario to achieve cell shape change instead of cell division. We discuss the occurrences of actomyosin rings aside from cell division, suggesting that circumferential contraction is an evolutionally conserved mechanism to drive cell or tissue elongation. PMID:24503569

  4. Functional Loss of Bmsei Causes Thermosensitive Epilepsy in Contractile Mutant Silkworm, Bombyx mori

    Science.gov (United States)

    Nie, Hongyi; Cheng, Tingcai; Huang, Xiaofeng; Zhou, Mengting; Zhang, Yinxia; Dai, Fangyin; Mita, Kazuei; Xia, Qingyou; Liu, Chun

    2015-07-01

    The thermoprotective mechanisms of insects remain largely unknown. We reported the Bombyx mori contractile (cot) behavioral mutant with thermo-sensitive seizures phenotype. At elevated temperatures, the cot mutant exhibit seizures associated with strong contractions, rolling, vomiting, and a temporary lack of movement. We narrowed a region containing cot to ~268 kb by positional cloning and identified the mutant gene as Bmsei which encoded a potassium channel protein. Bmsei was present in both the cell membrane and cytoplasm in wild-type ganglia but faint in cot. Furthermore, Bmsei was markedly decreased upon high temperature treatment in cot mutant. With the RNAi method and injecting potassium channel blockers, the wild type silkworm was induced the cot phenotype. These results demonstrated that Bmsei was responsible for the cot mutant phenotype and played an important role in thermoprotection in silkworm. Meanwhile, comparative proteomic approach was used to investigate the proteomic differences. The results showed that the protein of Hsp-1 and Tn1 were significantly decreased and increased on protein level in cot mutant after thermo-stimulus, respectively. Our data provide insights into the mechanism of thermoprotection in insect. As cot phenotype closely resembles human epilepsy, cot might be a potential model for the mechanism of epilepsy in future.

  5. Multiple effects of sibutramine on ejaculation and on vas deferens and seminal vesicle contractility.

    Science.gov (United States)

    Nojimoto, Fernanda D; Piffer, Renata C; Kiguti, Luiz Ricardo de A; Lameu, Claudiana; de Camargo, Antônio C M; Pereira, Oduvaldo C M; Pupo, André S

    2009-09-15

    Sibutramine is an inhibitor of norepinephrine and 5-HT reuptake largely used in the management of obesity. Although a fairly safe drug, postmarketing adverse effects of sibutramine were reported including abnormal ejaculation in men. This study investigates the effects of sibutramine on ejaculation and vas deferens and seminal vesicle contractility. Adult male rats received sibutramine (5; 20; or 50 mg kg(-1), ip) and after 60 min were exposed to receptive females for determination of ejaculation parameters. The vasa deferentia and seminal vesicles of untreated rats were mounted in isolated organ baths for recording of isometric contractions and HEK293 cells loaded with fluorescent calcium indicator were used to measure intracellular Ca(2+) transients. Sibutramine 5 and 20 mg kg(-1) reduced ejaculation latency whereas 50 mg kg(-1) increased ejaculation latency. Sibutramine 3 to 30 microM greatly increased the sensitivity of the seminal vesicle and vas deferens to norepinephrine, but at concentrations higher than 10 microM there were striking depressions of maximal contractions induced by norepinephrine, carbachol and CaCl(2). In HEK293 cells, sibutramine 10 to 100 microM inhibited intracellular Ca(2+) transients induced by carbachol. Depending on the doses, sibutramine either facilitates or inhibits ejaculation. Apart from its actions in the central nervous system, facilitation of ejaculation may result from augmented sensitivity of smooth muscles to norepinephrine while reductions of intracellular Ca(2+) may be involved in the delayed ejaculation observed with high doses of sibutramine.

  6. Multiple effects of sibutramine on ejaculation and on vas deferens and seminal vesicle contractility

    International Nuclear Information System (INIS)

    Nojimoto, Fernanda D.; Piffer, Renata C.; Kiguti, Luiz Ricardo de A.; Lameu, Claudiana; Camargo, Antonio C.M. de; Pereira, Oduvaldo C.M.; Pupo, Andre S.

    2009-01-01

    Sibutramine is an inhibitor of norepinephrine and 5-HT reuptake largely used in the management of obesity. Although a fairly safe drug, postmarketing adverse effects of sibutramine were reported including abnormal ejaculation in men. This study investigates the effects of sibutramine on ejaculation and vas deferens and seminal vesicle contractility. Adult male rats received sibutramine (5; 20; or 50 mg kg -1 , ip) and after 60 min were exposed to receptive females for determination of ejaculation parameters. The vasa deferentia and seminal vesicles of untreated rats were mounted in isolated organ baths for recording of isometric contractions and HEK293 cells loaded with fluorescent calcium indicator were used to measure intracellular Ca 2+ transients. Sibutramine 5 and 20 mg kg -1 reduced ejaculation latency whereas 50 mg kg -1 increased ejaculation latency. Sibutramine 3 to 30 μM greatly increased the sensitivity of the seminal vesicle and vas deferens to norepinephrine, but at concentrations higher than 10 μM there were striking depressions of maximal contractions induced by norepinephrine, carbachol and CaCl 2 . In HEK293 cells, sibutramine 10 to 100 μM inhibited intracellular Ca 2+ transients induced by carbachol. Depending on the doses, sibutramine either facilitates or inhibits ejaculation. Apart from its actions in the central nervous system, facilitation of ejaculation may result from augmented sensitivity of smooth muscles to norepinephrine while reductions of intracellular Ca 2+ may be involved in the delayed ejaculation observed with high doses of sibutramine.

  7. Human embryonic stem cell derived mesenchymal progenitors express cardiac markers but do not form contractile cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Christophe M Raynaud

    Full Text Available Mesenchymal progenitors or stromal cells have shown promise as a therapeutic strategy for a range of diseases including heart failure. In this context, we explored the growth and differentiation potential of mesenchymal progenitors (MPs derived in vitro from human embryonic stem cells (hESCs. Similar to MPs isolated from bone marrow, hESC derived MPs (hESC-MPs efficiently differentiated into archetypical mesenchymal derivatives such as chondrocytes and adipocytes. Upon treatment with 5-Azacytidine or TGF-β1, hESC-MPs modified their morphology and up-regulated expression of key cardiac transcription factors such as NKX2-5, MEF2C, HAND2 and MYOCD. Nevertheless, NKX2-5+ hESC-MP derivatives did not form contractile cardiomyocytes, raising questions concerning the suitability of these cells as a platform for cardiomyocyte replacement therapy. Gene profiling experiments revealed that, although hESC-MP derived cells expressed a suite of cardiac related genes, they lacked the complete repertoire of genes associated with bona fide cardiomyocytes. Our results suggest that whilst agents such as TGF-β1 and 5-Azacytidine can induce expression of cardiac related genes, but treated cells retain a mesenchymal like phenotype.

  8. Pharmacological characterization and chemical fractionation of a liposterolic extract of saw palmetto (Serenoa repens): effects on rat prostate contractility.

    Science.gov (United States)

    Chua, Thiam; Eise, Nicole T; Simpson, Jamie S; Ventura, Sabatino

    2014-03-14

    Saw palmetto (Serenoa repens) was first used medicinally by native American Indians to treat urological disorders. Nowadays, saw palmetto extracts are widely used in Europe and North America to treat the urinary symptoms associated with benign prostatic hyperplasia even though its mechanisms of action are poorly understood. This study aimed to characterize the bioactive constituents of a lipid extract of saw palmetto that are able to affect contractility of the rat prostate gland. The mechanism of action will also be investigated. A commercially available lipid extract of saw palmetto was subjected to fractionation using normal phase column chromatography. Composition of fractions was assessed by proton nuclear magnetic resonance spectroscopy ((1)H NMR) and mass spectrometry (MS). Contractile activities of these fractions were evaluated pharmacologically using isolated preparations of rat prostate gland and compared to the activity of the crude extract. Saw palmetto extract inhibited contractions of the rat prostate gland which were consistent with smooth muscle relaxant activity. Only the ethyl acetate fraction resulting from chromatography inhibited contractions of isolated rat prostates similarly to the inhibition produced by the crude lipid extract. Comparison with authentic samples and analysis of NMR data revealed that this bioactivity was due to the fatty acid components present in the ethyl acetate fraction. Bioassay using various pharmacological tools identified multiple contractile mechanisms which were affected by the bioactive constituents. A fatty acid component of saw palmetto extract causes inhibition of prostatic smooth muscle contractions via a non-specific mechanism. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. The effect of N-acetylcysteine on cardiac contractility to dobutamine in rats with streptozotocin-induced diabetes.

    Science.gov (United States)

    Cheng, Xing; Xia, Zhengyuan; Leo, Joyce M; Pang, Catherine C Y

    2005-09-05

    We examined if myocardial depression at the acute phase of diabetes (3 weeks after injection of streptozotocin, 60 mg/kg i.v.) is due to activation of inducible nitric oxide synthase and production of peroxynitrite, and if treatment with N-acetylcysteine (1.2 g/day/kg for 3 weeks, antioxidant) improves cardiac function. Four groups of rats were used: control, N-acetylcysteine-treated control, diabetic and N-acetylcysteine-treated diabetic. Pentobarbital-anaesthetized diabetic rats, relative to the controls, had reduced left ventricular contractility to dobutamine (1-57 microg/min/kg). The diabetic rats also had increased myocardial levels of thiobarbituric acid reactive substances, immunostaining of inducible nitric oxide synthase and nitrotyrosine, and similar baseline 15-F2t-isoprostane. N-acetylcysteine did not affect responses in the control rats; but increased cardiac contractility to dobutamine, reduced myocardial immunostaining of inducible nitric oxide synthase and nitrotyrosine and level of 15-F2t-isoprostane, and increased cardiac contractility to dobutamine in the diabetic rats. Antioxidant supplementation in diabetes reduces oxidative stress and improves cardiac function.

  10. The effects of space flight on the contractile apparatus of antigravity muscles: implications for aging and deconditioning

    Science.gov (United States)

    Baldwin, K. M.; Caiozzo, V. J.; Haddad, F.; Baker, M. J.; Herrick, R. E.

    1994-01-01

    Previous studies have shown that the unloading of skeletal muscle, as occurring during exposure to space flight, exerts a profound effect on both the mass (cross sectional area) of skeletal muscle fibers and the relative expression of protein isoforms comprising the contractile system. Available information suggests that slow (type I) fibers, comprising chiefly the antigravity muscles of experimental animals, in addition to atrophying, undergo alterations in the type of myosin heavy chain (MHC) expressed such that faster isoforms become concomitantly expressed in a sub-population of slow fibers when insufficient force-bearing activity is maintained on the muscle. Consequently, these transformations in both mass and myosin heavy chain phenotype could exert a significant impact on the functional properties of skeletal muscle as manifest in the strength, contractile speed, and endurance scope of the muscle. To further explore these issues, a study was performed in which young adult male rats were exposed to zero gravity for six days, following which, the antigravity soleus muscle was examined for a) contractile properties, determined in situ and b) isomyosin expression, as studied using biochemical, molecular biology, and histochemical/immunohistochemical techniques.

  11. Towards a Tissue-Engineered Contractile Fontan-Conduit: The Fate of Cardiac Myocytes in the Subpulmonary Circulation.

    Directory of Open Access Journals (Sweden)

    Daniel Biermann

    Full Text Available The long-term outcome of patients with single ventricles improved over time, but remains poor compared to other congenital heart lesions with biventricular circulation. Main cause for this unfavourable outcome is the unphysiological hemodynamic of the Fontan circulation, such as subnormal systemic cardiac output and increased systemic-venous pressure. To overcome this limitation, we are developing the concept of a contractile extracardiac Fontan-tunnel. In this study, we evaluated the survival and structural development of a tissue-engineered conduit under in vivo conditions. Engineered heart tissue was generated from ventricular heart cells of neonatal Wistar rats, fibrinogen and thrombin. Engineered heart tissues started beating around day 8 in vitro and remained contractile in vivo throughout the experiment. After culture for 14 days constructs were implanted around the right superior vena cava of Wistar rats (n = 12. Animals were euthanized after 7, 14, 28 and 56 days postoperatively. Hematoxylin and eosin staining showed cardiomyocytes arranged in thick bundles within the engineered heart tissue-conduit. Immunostaining of sarcomeric actin, alpha-actin and connexin 43 revealed a well -developed cardiac myocyte structure. Magnetic resonance imaging (d14, n = 3 revealed no constriction or stenosis of the superior vena cava by the constructs. Engineered heart tissues survive and contract for extended periods after implantation around the superior vena cava of rats. Generation of larger constructs is warranted to evaluate functional benefits of a contractile Fontan-conduit.

  12. Contractile Defect Caused by Mutation in MYBPC3 Revealed under Conditions Optimized for Human PSC-Cardiomyocyte Function

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    Matthew J. Birket

    2015-10-01

    Full Text Available Maximizing baseline function of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs is essential for their effective application in models of cardiac toxicity and disease. Here, we aimed to identify factors that would promote an adequate level of function to permit robust single-cell contractility measurements in a human induced pluripotent stem cell (hiPSC model of hypertrophic cardiomyopathy (HCM. A simple screen revealed the collaborative effects of thyroid hormone, IGF-1 and the glucocorticoid analog dexamethasone on the electrophysiology, bioenergetics, and contractile force generation of hPSC-CMs. In this optimized condition, hiPSC-CMs with mutations in MYBPC3, a gene encoding myosin-binding protein C, which, when mutated, causes HCM, showed significantly lower contractile force generation than controls. This was recapitulated by direct knockdown of MYBPC3 in control hPSC-CMs, supporting a mechanism of haploinsufficiency. Modeling this disease in vitro using human cells is an important step toward identifying therapeutic interventions for HCM.

  13. Effects of Using Tricaine Methanesulfonate and Metomidate before Euthanasia on the Contractile Properties of Rainbow Trout (Oncorhynchus mykiss) Myocardium.

    Science.gov (United States)

    Roberts, Jordan C; Syme, Douglas A

    2016-01-01

    Because many anesthetics work through depressing cell excitability, unanesthetized euthanasia has become common for research involving excitable tissues (for example muscle and nerve) to avoid these depressive effects. However, anesthetic use during euthanasia may be indicated for studies involving isolated tissues if the potential depressive effects of brief anesthetic exposure dissipate after subsequent tissue isolation, washout, and saline perfusion. We explore this here by measuring whether, when applied prior to euthanasia, standard immersion doses of 2 fish anesthetics, tricaine methanesulfonate (TMS; 100 mg/L, n = 6) and methyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylate (metomidate, 10 mg/L, n = 6), have residual effects on the contractile properties (force and work output) of isolated and saline-perfused ventricular compact myocardium from rainbow trout (Oncorhynchus mykiss). Results suggest that direct exposure of muscle to immersion doses of TMS-but not metomidate-impairs muscle contractile performance. However, brief exposure (2 to 3 min) to either anesthetic during euthanasia only-providing that the agent is washed out prior to tissue experimentation-does not have an effect on the contractile properties of the myocardium. Therefore, the use of TMS, metomidate, and perhaps other anesthetics that depress cell excitability during euthanasia may be indicated when conducting research on isolated and rinsed tissues.

  14. Generation of Functional Cardiomyocytes from Efficiently Generated Human iPSCs and a Novel Method of Measuring Contractility.

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    Sheeja Rajasingh

    Full Text Available Human induced pluripotent stem cells (iPSCs derived cardiomyocytes (iCMCs would provide an unlimited cell source for regenerative medicine and drug discoveries. The objective of our study is to generate functional cardiomyocytes from human iPSCs and to develop a novel method of measuring contractility of CMCs. In a series of experiments, adult human skin fibroblasts (HSF and human umbilical vein endothelial cells (HUVECs were treated with a combination of pluripotent gene DNA and mRNA under specific conditions. The iPSC colonies were identified and differentiated into various cell lineages, including CMCs. The contractile activity of CMCs was measured by a novel method of frame-by-frame cross correlation (particle image velocimetry-PIV analysis. Our treatment regimen transformed 4% of HSFs into iPSC colonies at passage 0, a significantly improved efficiency compared with use of either DNA or mRNA alone. The iPSCs were capable of differentiating both in vitro and in vivo into endodermal, ectodermal and mesodermal cells, including CMCs with >88% of cells being positive for troponin T (CTT and Gata4 by flow cytometry. We report a highly efficient combination of DNA and mRNA to generate iPSCs and functional iCMCs from adult human cells. We also report a novel approach to measure contractility of iCMCs.

  15. Generation of Functional Cardiomyocytes from Efficiently Generated Human iPSCs and a Novel Method of Measuring Contractility.

    Science.gov (United States)

    Rajasingh, Sheeja; Thangavel, Jayakumar; Czirok, Andras; Samanta, Saheli; Roby, Katherine F; Dawn, Buddhadeb; Rajasingh, Johnson

    2015-01-01

    Human induced pluripotent stem cells (iPSCs) derived cardiomyocytes (iCMCs) would provide an unlimited cell source for regenerative medicine and drug discoveries. The objective of our study is to generate functional cardiomyocytes from human iPSCs and to develop a novel method of measuring contractility of CMCs. In a series of experiments, adult human skin fibroblasts (HSF) and human umbilical vein endothelial cells (HUVECs) were treated with a combination of pluripotent gene DNA and mRNA under specific conditions. The iPSC colonies were identified and differentiated into various cell lineages, including CMCs. The contractile activity of CMCs was measured by a novel method of frame-by-frame cross correlation (particle image velocimetry-PIV) analysis. Our treatment regimen transformed 4% of HSFs into iPSC colonies at passage 0, a significantly improved efficiency compared with use of either DNA or mRNA alone. The iPSCs were capable of differentiating both in vitro and in vivo into endodermal, ectodermal and mesodermal cells, including CMCs with >88% of cells being positive for troponin T (CTT) and Gata4 by flow cytometry. We report a highly efficient combination of DNA and mRNA to generate iPSCs and functional iCMCs from adult human cells. We also report a novel approach to measure contractility of iCMCs.

  16. Na+/Ca2+ exchanger inhibition exerts a positive inotropic effect in the rat heart, but fails to influence the contractility of the rabbit heart

    OpenAIRE

    Farkas, A S; Acsai, K; Nagy, N; Tóth, A; Fülöp, F; Seprényi, G; Birinyi, P; Nánási, P P; Forster, T; Csanády, M; Papp, J G; Varró, A; Farkas, A

    2008-01-01

    Background and purpose: The Na+/Ca2+ exchanger (NCX) may play a key role in myocardial contractility. The operation of the NCX is affected by the action potential (AP) configuration and the intracellular Na+ concentration. This study examined the effect of selective NCX inhibition by 0.1, 0.3 and 1.0 μM SEA0400 on the myocardial contractility in the setting of different AP configurations and different intracellular Na+ concentrations in rabbit and rat hearts.

  17. Regulation of myofibrillar accumulation in chick muscle cultures - Evidence for the involvement of calcium and lysosomes in non-uniform turnover of contractile proteins

    Science.gov (United States)

    Silver, Geri; Etlinger, Joseph D.

    1985-01-01

    The effects of calcium on the synthesis and the degradation of individual myofibrillar proteins were investigated using primary chick-leg skeletal muscle cultures labeled with S-35-methionine (for protein accumulation experiments) or Ca(2+)-45 (for calcium efflux experiments). It was found that the turnover of individual contractile proteins is regulated nonuniformly by a calcium-dependent mechanism involving lysosomes. The results also indicate that contractile proteins are released from the myofibril before their breakdown to amino acids.

  18. Regulation of glycogen synthesis in rat skeletal muscle after glycogen-depleting contractile activity: effects of adrenaline on glycogen synthesis and activation of glycogen synthase and glycogen phosphorylase.

    OpenAIRE

    Franch, J; Aslesen, R; Jensen, J

    1999-01-01

    We investigated the effects of insulin and adrenaline on the rate of glycogen synthesis in skeletal muscles after electrical stimulation in vitro. The contractile activity decreased the glycogen concentration by 62%. After contractile activity, the glycogen stores were fully replenished at a constant and high rate for 3 h when 10 m-i.u./ml insulin was present. In the absence of insulin, only 65% of the initial glycogen stores was replenished. Adrenaline decreased insulin-stimulated glycogen s...

  19. Capacidad antiteratogénica del resveratrol en diabetes inducida por estreptozotocina en ratas

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    Ninna Leslie Trejo-González

    Full Text Available Objetivos. Evaluar la capacidad antihiperglucémica y antiteratogénica del resveratrol en ratas inducidas a diabetes por estreptozotocina. Materiales y métodos. Estudio de tipo experimental. Se tuvieron tres grupos, de cinco ratas Wistar preñadas cada uno, dos de los cuales fueron tratados el cuarto día de gestación con una dosis de estreptozotocina de 50 mg/kg, disuelta en tampón de citratos, y el otro fue considerado como control, y solo se le administró el tampón de citratos. A uno de los grupos inducidos con estreptozotocina se le administró resveratrol a dosis de 100 mg/kg durante los días 8 al 12 de gestación, cuando sucede la neurulación. Los fetos se obtuvieron el día 19 de gestación y se les realizó un análisis morfológico, y en el hígado fetal se determinó la actividad de las enzimas depuradoras de especies reactivas catalasa, superóxido dismutasa y glutatión peroxidasa. Resultados. La administración de resveratrol (DM+R revierte los parámetros a valores similares a los del grupo control. Las actividades de catalasa y de glutatión peroxidasa, se vieron incrementadas en el grupo tratado con resveratrol con respecto al grupo diabético, en cuanto a la frecuencia de malformaciones en el grupo control y en el grupo tratado con resveratrol no presentaron malformaciones, mientras que en las ratas con diabetes inducida, se encontró una elevada frecuencia de malformaciones. Conclusiones. El resveratrol muestra propiedades antiteratogénicas a través de la disminución del estrés oxidativo que se presenta a causa de la hiperglucemia materna

  20. CAPACIDADE DE DESENVOLVER TRABALHO FÍSICO PROGRESSIVO EM CONDIÇÕES DE HIPOTERMIA BRANDA

    Directory of Open Access Journals (Sweden)

    Bárbara Regina Alvarez

    2008-07-01

    Full Text Available O propósito deste estudo determinar, em 12 voluntários do Grupo de Busca e Salvamento da Polícia Militar de Santa Catarina, a capacidade de desenvolver trabalho físico na bicicleta ergométrica (cargas escalonadas de 50, 100 e 150 watt em condições ambientais neutras (28 graus e subnormal (20 graus, com varredura ampliada da temperatura cutânea (7 sensores periféricos, da temperatura central (sensor piloto e da temperatura ambiental (sensor referência, a estimativa do VO2 máximo foi efetuada com auxílio do nomograma desenvolvido por Astrand (1960, empregando um cicloergômetro de frenagem magnética da FUNBEC. Já o % de mobilização do VO2 max foi predito pela equação proposta por Katch (1978, empregando o % da mobilidade da FC. Os dados foram tratados através da ferramenta eletrônica MICROSTAT, empregando o artifício estático "t" de student monocaudal. Foi observada uma variação significativa (P < 0.05 na temperatura de repouso entre as duas condições (%= -0.52. Considerando a estimativa do valor padrão (3 watt/Kg, a PWC170 apresentou uma diferença significativa entre médias (%=-14.29. A sobreposição dos pontos térmicos evidenciou um marcado estado de equilíbrio na FC nos minutos finais de cada desempenho biológico, corroborando a hipótese de ajustamento imediato dos sistemas cardiorrespiratório e metabólico para atender a demanda tecidual de oxigênio e nutrientes. Para estudos complementares, sugerimos a utilização da banda inferior da zona hipotérmica (flutuação de 20 a 5 graus Celsius para que o impacto da condição subnormal produza alterações mais importantes na temperatura central.

  1. Fenólicos totais e capacidade antioxidante in vitro de polpas de frutos tropicais

    Directory of Open Access Journals (Sweden)

    Luanne Morais Vieira

    2011-09-01

    Full Text Available O consumo de frutos e suas polpas tem sido muito recomendado por seu valor nutricional, alto teor de fibras, vitamina C e carotenoides. Trabalhos recentes têm apontado esses alimentos como fontes de compostos fenólicos com ação antioxidante, portanto sequestradores de radicais livres, com ação protetora contra o surgimento e/ou desenvolvimento de processos degenerativos que conduzem a doenças crônicas não transmissíveis. Devido à crescente comercialização e consumo de polpas de frutas no Brasil, especialmente na cidade de Teresina-Piauí, este trabalho selecionou um grupo de polpas de frutos de elevado consumo local para avaliação do teor de fenólicos totais e da atividade antioxidante in vitro pelo método de captura de radicais livres: DPPH (radical 1,1-diphenil-2-picrilhydrazil e ABTS (radical 2,2'azinobis(3-ethylbenzthiazoline-6-sulfonic acid. Os frutos selecionados foram: Acerola (Malpighia emarginata DC., Bacuri (Platonia insignis Mart., Cajá (Spondias mombin L., Caju (Anacardium occidentale, Goiaba(Psidium guajava e Tamarindo (Tamarindus indica L.. Os teores de fenólicos totais encontrados nas polpascongeladas destes frutos exibiram quantidades relevantes de polifenóis, destacando-se a polpa de acerola com 835,25 ± 32,44 e 449,63 ± 10,24 mg /100g nos extratos aquosos e hidroalcoólicos, respectivamente, seguido pela polpa de caju com 201,61 ± 19,15 e 165,07 ± 4,10 mg /100g. As polpas de bacuri e tamarindo foram as que apresentaram os menores teores de fenólicos totais. Com relação à atividade antioxidante in vitro, os melhores resultados foram encontrados para os extratos aquosos e hidroalcoólicos das polpas de acerola, caju e goiaba. A capacidade antioxidante destas polpas (EC50 em µg/mL variou de 24,42 a 413,36 e de 1,74 a 259,18 para os extratos aquosos e hidroalcoólicos, respectivamente. Utilizando o radical ABTS, a atividade antioxidante para essas mesmas polpas de frutas apresentou valores TEAC que

  2. Da construção de capacidade avaliatória em iniciativas sociais: algumas reflexões Constructión de capacidad en avaluación Some reflections on building evaluation capacity on social initiatives

    Directory of Open Access Journals (Sweden)

    Daniel Braga Brandão

    2005-09-01

    Full Text Available Este ensaio discute alternativas de apoio ao desenvolvimento da capacidade avaliatória em organizações da sociedade civil. Nele são debatidos elementos estratégicos para apoiar processos de aprendizagem nas organizações e para fortalecer conquista de autonomia no campo da avaliação. Aborda-se a construção da capacidade avaliatória como processo de construção de sujeitos, e não como um movimento de natureza predominantemente técnica. Com base nos princípios de aprendizagem, autonomia, respeito e participação são propostas cinco dimensões estratégicas para apoiar o desenvolvimento de capacidade avaliatória: 1 a consciência a respeito e a capacidade de lidar com as relações de poder presentes nas ações avaliatórias; 2 a busca de razões e motivação para avaliar as práticas; 3 a construção de um certo grau de identidade organizacional em torno da avaliação; 4 o desenvolvimento de competências no campo da facilitação e gestão de processos e da investigação da realidade, necessárias a realização de avaliações; 5 a captação e alocação de recursos para criar as condições de trabalho necessárias aos processos de avaliação.Este texto trata de la construcción de capacidades en evaluación en organizaciones de la sociedad civil. Aborda el tema orientado por los proceso de aprendijage organizacional y considera cinco dimensiones presentes en la construcción de la capacidad en evaluación en una organización: 1 Las relaciones de poder entre los stakholders y sus consecuencias en las decisiones; 2 Las razones y los motivos para desarrollar una evaluación; 3 La elaboración de una identidad organizacional para la evaluación; 4 La necesidad del desarrollo de competencias en evaluación y 5 La necesidad de garantizar y manejar fondos para la evaluación.This essay focuses on building evaluation capacity in civil society organizations. It considers aspects to support the organizational learning process

  3. Role of contractile prostaglandins and Rho-kinase in growth factor-induced airway smooth muscle contraction

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    Zaagsma Johan

    2005-07-01

    Full Text Available Abstract Background In addition to their proliferative and differentiating effects, several growth factors are capable of inducing a sustained airway smooth muscle (ASM contraction. These contractile effects were previously found to be dependent on Rho-kinase and have also been associated with the production of eicosanoids. However, the precise mechanisms underlying growth factor-induced contraction are still unknown. In this study we investigated the role of contractile prostaglandins and Rho-kinase in growth factor-induced ASM contraction. Methods Growth factor-induced contractions of guinea pig open-ring tracheal preparations were studied by isometric tension measurements. The contribution of Rho-kinase, mitogen-activated protein kinase (MAPK and cyclooxygenase (COX to these reponses was established, using the inhibitors Y-27632 (1 μM, U-0126 (3 μM and indomethacin (3 μM, respectively. The Rho-kinase dependency of contractions induced by exogenously applied prostaglandin F2α (PGF2α and prostaglandin E2 (PGE2 was also studied. In addition, the effects of the selective FP-receptor antagonist AL-8810 (10 μM and the selective EP1-antagonist AH-6809 (10 μM on growth factor-induced contractions were investigated, both in intact and epithelium-denuded preparations. Growth factor-induced PGF2α-and PGE2-release in the absence and presence of Y-27632, U-0126 and indomethacin, was assessed by an ELISA-assay. Results Epidermal growth factor (EGF-and platelet-derived growth factor (PDGF-induced contractions of guinea pig tracheal smooth muscle preparations were dependent on Rho-kinase, MAPK and COX. Interestingly, growth factor-induced PGF2α-and PGE2-release from tracheal rings was significantly reduced by U-0126 and indomethacin, but not by Y-27632. Also, PGF2α-and PGE2-induced ASM contractions were largely dependent on Rho-kinase, in contrast to other contractile agonists like histamine. The FP-receptor antagonist AL-8810 (10 μM significantly

  4. Capacidades dinâmicas na Controladoria-Geral da União : estudo de caso nas capacidades operacionais de auditoria e fiscalização em compras e licitações

    OpenAIRE

    Souza, Cristiano Coimbra de

    2014-01-01

    O pensamento estratégico administrativo tem muitas abordagens teóricas, dentre elas o pensamento sobre as Capacidades Dinâmicas (CD) das organizações, de ramificação de estudos econômicos das firmas, voltado a descrever como acontecem processos específicos para manutenção do desempenho organizacional em ambientes dinâmicos, dentre eles aspectos relacionados ao aprendizado organizacional e à gestão do conhecimento. Utilizando essa teoria como principal referencial teórico, o estudo teve como o...

  5. Modelo de capacidad dinámica de aprendizaje organizacional: experiencia de la biotecnológia en Cuba

    Directory of Open Access Journals (Sweden)

    Marle Pérez de Armas

    2016-01-01

    Full Text Available La experiencia y práctica internacional fundamentan el conocimiento como recurso estratégico y resultado del aprendizaje organizacional, lo que conduce a plantear la Capacidad Dinámica de Aprendizaje Organizacional vinculada con la obtención de resultados de desempeños positivos y fuente de ventajas competitivas. En este sentido, la empresa de alta tecnología (EAT del sector de la biotecnología en Cuba representa una experiencia singular lo que se vincula con el problema científico, ya que se necesita explicar, sobre bases científicas, cómo el desarrollo de la Capacidad Dinámica de Aprendizaje Organizacional contribuye a fundamentar el éxito alcanzado por empresas líderes del sector, y que a su vez posibiliten su extensión a otras de su tipo en el sector. A partir de la utilización de la metodología de estudio de caso aplicada al Centro de Inmunología Molecular como caso piloto y el juicio de expertos se obtiene como, principal resultado, un modelo conceptual que fundamenta y explica el éxito alcanzado por empresas líderes de alta tecnología del sector biotecnológico cubano desde el desarrollo de la Capacidad Dinámica de Aprendizaje Organizacional y sus tres dimensiones claves: elementos de gestión técnico-organizativos, comportamiento organizacional y actores externos.

  6. El cortometraje como herramienta innovadora para el alumnado con Altas Capacidades en Educación Primaria

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    Ana Belén Fernández del Río

    2017-05-01

    Full Text Available El presente estudio muestra los resultados de una experiencia implementada con alumnado de Altas Capacidades de Educación Primaria utilizando el cortometraje como estrategia innovadora basada en la animación y creación audiovisual, para la mejora de sus potencialidades. Se pretende, por un lado, analizar la progresión de dichos estudiantes y, por otro, ejemplificar dicho análisis utilizando la técnica short-films, dando a conocer sus posibilidades como herramienta didáctico-pedagógica que promueva la mejora de su potencial creativo. De forma específica, se procura crear, manipular y combinar textos e imágenes de forma creativa, favorecer la adquisición de habilidades sociales, utilizar eficazmente procedimientos de búsqueda, recogida y procesamiento de la información, así como valorar los medios de comunicación social como instrumento para aprender a acceder a informaciones y experiencias. Como método de investigación se utiliza el estudio de casos y también la investigación-acción. La muestra seleccionada de carácter intencional está constituida por 12 estudiantes de Altas Capacidades de Educación Primaria. En el análisis cualitativo de los datos se utilizó el software ATLAS.ti. Tras la intervención se constata una mejora relevante en la creatividad del alumnado; así como un incremento en su motivación,  destacando  la adquisición y desarrollo de habilidades como el trabajo colaborativo en donde se aprenden estrategias para resolver problemas. Asimismo, habilidades interpersonales como la comunicación, el liderazgo y la capacidad de decisión.

  7. Modelo de capacidad dinámica de aprendizaje organizacional: experiencia de la biotecnología en Cuba

    Directory of Open Access Journals (Sweden)

    Marle Pérez De Armas

    2016-06-01

    Full Text Available La experiencia y práctica internacional fundamentan el conocimiento como recurso estratégico y resultado del aprendizaje organizacional, lo que conduce a plantear la Capacidad Dinámica de Aprendizaje Organizacional vinculada con la obtención de resultados de desempeños positivos y fuente de ventajas competitivas. En este sentido, la empresa de alta tecnología (EAT del sector de la biotecnología en Cuba representa una experiencia singular lo que se vincula con el problema científico, ya que se necesita explicar, sobre bases científicas, cómo el desarrollo de la Capacidad Dinámica de Aprendizaje Organizacional contribuye a fundamentar el éxito alcanzado por empresas líderes del sector, y que a su vez posibiliten su extensión a otras de su tipo en el sector. A partir de la utilización de la metodología de estudio de caso aplicada al Centro de Inmunología Molecular como caso piloto y el juicio de expertos se obtiene como, principal resultado, un modelo conceptual que fundamenta y explica el éxito alcanzado por empresas líderes de alta tecnología del sector biotecnológico cubano desde el desarrollo de la Capacidad Dinámica de Aprendizaje Organizacional y sus tres dimensiones claves: elementos de gestión técnico-organizativos, comportamiento organizacional y actores externos.

  8. CAPACIDAD TECNOLÓGICA Y POLÍTICAS PÚBLICAS DE LAS ORGANIZACIONES GESTORAS DE RIESGOS AMBIENTALES

    Directory of Open Access Journals (Sweden)

    Johana Quintero

    2014-07-01

    Full Text Available El desarrollo del País esta indivisiblemente unido al aprendizaje tecnológico que generan las capacidades tecnológicas necesarias para lograr un cambio tecnológico. La presente investigación analiza la capacidad tecnológica y las políticas públicas de las organizaciones que gestionan los riesgos ambientales en Venezuela y formula los lineamientos teóricos en materia de políticas públicas que beneficien la interrelación del estado venezolano con las organizaciones que gestionan de los riesgos. Para alcanzar los objetivos de la investigación, se fundamentó en las teorías de Mora y Barrios (2000, CLAD (2000, Gaynor (1999, Vásquez (2000, de la misma manera se consultaron leyes, decretos y normativas vigentes. La investigación fue de tipo descriptiva, documental, de campo, con un diseño no experimental transaccional descriptivo, correlacional, utilizando como técnicas e instrumentos de recolección de datos los documentos bibliográficos, el cuestionario y la entrevista, los cuales fueron aplicados a veintitrés sujetos quienes  representan los informantes claves de las organizaciones población de estudio. Con los resultados obtenidos se concluyó que la capacidad tecnológica se incorpora en forma creciente en las organizaciones debido a la consecución de sus cuatro componentes y se comprobó que interactúan entre si y cada uno de ellos contribuye de modo diferente a las mismas, permitiendo integrar las políticas públicas en materia de riesgos ambientales, para poder lograr así una orientación en la elaboración de lineamientos teóricos para el desarrollo de ambas variables.

  9. Swimming exercise reverses aging-related contractile abnormalities of female heart by improving structural alterations.

    Science.gov (United States)

    Ozturk, Nihal; Olgar, Yusuf; Er, Hakan; Kucuk, Murathan; Ozdemir, Semir

    2017-01-01

    The objective of this study was to examine the effect of swimming exercise on aging-related Ca2+ handling alterations and structural abnormalities of female rat heart. For this purpose, 4-month and 24-month old female rats were used and divided into three following groups: sedentary young (SY), sedentary old (SO), and exercised old (Ex-O). Swimming exercise was performed for 8 weeks (60 min/day, 5 days/week). Myocyte shortening, L-type Ca2+ currents and associated Ca2+ transients were measured from ventricular myocytes at 36 ± 1°C. NOX-4 levels, aconitase activity, glutathione measurements and ultrastructural examination by electron microscopy were conducted in heart tissue. Swimming exercise reversed the reduced shortening and slowed kinetics of aged cardiomyocytes. Although the current density was similar for all groups, Ca2+ transients were higher in SO and Ex-O myocytes with respect to the SY group. Caffeine-induced Ca2+ transients and the integrated NCX current were lower in cardiomyocytes of SY rats compared with other groups, suggesting an increased sarcoplasmic reticulum Ca2+ content in an aged heart. Aging led to upregulated cardiac NOX-4 along with declined aconitase activity. Although it did not reverse these oxidative parameters, swimming exercise achieved a significant increase in glutathione levels and improved structural alterations of old rats' hearts. We conclude that swimming exercise upregulates antioxidant defense capacity and improves structural abnormalities of senescent female rat heart, although it does not change Ca2+ handling alterations further. Thereby, it improves contractile function of aged myocardium by mitigating detrimental effects of oxidative stress.

  10. In Vitro Contractile Response of Rabbit Myometrium to BKCa and KATP Potassium Channel Openers

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    Soňa Fraňová

    2009-01-01

    Full Text Available The aim of the study was to evaluate the participation of ligand-sensitive potassium large conductance calcium-activated channels (BKCa and ATP-sensitive potassium channels in uterine smooth muscle reactivity during different stages of the experimentally induced proliferatory and secretory phase in the sexual cycle in ovariectomised rabbits in vitro. The myometrial reactivity to oxytocin (10-6 mol l-1 was investigated by an in vitro method in female rabbits 14 days after ovariectomy treated with 17β-estradiol - 1 mg/kg/day i.m. for 7 days, or with a combination of progesterone 2 mg/kg/day s.c. for 7 days and 17β-estradiol - 0.2 mg/ kg/day (day 3–7. The strips of myometrial smooth muscle were incubated with a specific opener (NS 1619 and an antagonist (TEA of potassium large conductance calcium-activated channel, or with a specific opener (pinacidil and an antagonist (glybenclamide of ATP-sensitive potassium channels before the administration of oxytocin. NS1619 produced more potent inhibition of the oxytocin-induced contraction during the gestagen dominance (experimental secretory phase than the one observed during the oestrogen dominance (experimental proliferatory phase. TEA antagonized the NS1619 induced inhibition of the myometrial contraction. In the matter of KATP potassium channels, after the administration of pinacidil we observed a similar situation in the changes of myometrial contractility. Pinacidil produced more pronounced inhibition of oxytocin-induced contraction during the secretory phase, and its effect was abolished by the selective inhibitor glybenclamide. Our experimental results indicate that both potassium large conductance calcium-activated channels and ATP-sensitive potassium channels significantly participate in the regulation of myometrial oxytocin-induced contractions and the activity of these channels is probably influenced by the levels of oestrogens and gestagens.

  11. Effects of high-altitude exercise training on contractile function of rat skinned cardiomyocyte.

    Science.gov (United States)

    Cazorla, O; Aït Mou, Y; Goret, L; Vassort, G; Dauzat, M; Lacampagne, A; Tanguy, S; Obert, P

    2006-09-01

    Previous studies have questioned whether there is an improved cardiac function after high-altitude training. Accordingly, the present study was designed specifically to test whether this apparent blunted response of the whole heart to training can be accounted for by altered mechanical properties at the cellular level. Adult rats were trained for 5 weeks under normoxic (N, NT for sedentary and trained animals, respectively) or hypobaric hypoxic (H, HT) conditions. Cardiac morphology and function were evaluated by echocardiography. Calcium Ca2+ sensitivity of the contractile machinery was estimated in skinned cardiomyocytes isolated from the left ventricular (LV) sub-epicardium (Epi) and sub-endocardium (Endo) at short and long sarcomere lengths (SL). Cardiac remodelling was harmonious (increase in wall thickness with chamber dilatation) in NT rats and disharmonious (hypertrophy without chamber dilatation) in HT rats. Contrary to NT rats, HT rats did not exhibit enhancement in global cardiac performance evaluated by echocardiography. Stretch- dependent Ca2+ sensitization of the myofilaments (cellular index of the Frank-Starling mechanism) increased from Epi to Endo in N rats. Training in normoxic conditions further increased this stretch-dependent Ca2+ sensitization. Chronic hypoxia did not significantly affect myofibrilar Ca2+ sensitivity. In contrast, high-altitude training decreased Ca2+ sensitivity of the myofilaments at both SL, mostly in Endo cells, resulting in a loss of the transmural gradient of the stretch-dependent Ca2+ sensitization. Expression of myosin heavy chain isoforms was affected both by training and chronic hypoxia but did not correlate with mechanical data. Training at sea level increased the transmural gradient of stretch-dependent Ca2+ sensitization of the myofilaments, accounting for an improved Frank-Starling mechanism. High-altitude training depressed myofilament response to Ca2+, especially in the Endo layer. This led to a reduction in

  12. Modification of abomasum contractility by flavonoids present in ruminants diet: in vitro study.

    Science.gov (United States)

    Mendel, M; Chłopecka, M; Dziekan, N; Karlik, W

    2016-09-01

    Flavonoid supplementation is likely to be beneficial in improving rumen fermentation and in reducing the incidence of rumen acidosis and bloat. Flavonoids are also said to increase the metabolic performance during the peripartum period. Ruminants are constantly exposed to flavonoids present in feed. However, it is not clear if these phytochemicals can affect the activity of the gut smooth muscle. Therefore, the aim of the study was to verify the effect of three flavonoids on bovine isolated abomasum smooth muscle. The study was carried out on bovine isolated circular and longitudinal abomasal smooth muscle specimens. All experiments were conducted under isometric conditions. The effect of apigenin, luteolin and quercetin (0.001 to 100 µM) was evaluated on acetylcholine-precontracted preparations. The effect of multiple, but not cumulative, treatment and single treatment with each flavonoid on abomasum strips was compared. Apigenin (0.1 to 100 µM) dose-dependently showed myorelaxation effects. Luteolin and quercetin applied in low doses increased the force of the ACh-evoked reaction. However, if used in high doses in experiments testing a wide range of concentrations, their contractile effect either declined (luteolin) or was replaced by an antispasmodic effect (quercetin). Surprisingly, the reaction induced by flavonoids after repeated exposure to the same phytochemical was not reproducible in experiments testing only single exposure of abomasum strips to the same flavonoid used in a high concentration. Taking into account the physicochemical properties of flavonoids, this data suggests the ability of flavonoids to interfere with cell membranes and, subsequently, to modify their responsiveness. Assuming ruminant supplementation with luteolin or quercetin or their presence in daily pasture, a reduction of the likelihood of abomasum dysmotility should be expected.

  13. Deletion of Dicer in smooth muscle affects voiding pattern and reduces detrusor contractility and neuroeffector transmission.

    Directory of Open Access Journals (Sweden)

    Mardjaneh Karbalaei Sadegh

    Full Text Available MicroRNAs have emerged as important regulators of smooth muscle phenotype and may play important roles in pathogenesis of various smooth muscle related disease states. The aim of this study was to investigate the role of miRNAs for urinary bladder function. We used an inducible and smooth muscle specific Dicer knockout (KO mouse which resulted in significantly reduced levels of miRNAs, including miR-145, miR-143, miR-22, miR125b-5p and miR-27a, from detrusor preparations without mucosa. Deletion of Dicer resulted in a disturbed micturition pattern in vivo and reduced depolarization-induced pressure development in the isolated detrusor. Furthermore, electrical field stimulation revealed a decreased cholinergic but maintained purinergic component of neurogenic activation in Dicer KO bladder strips. The ultrastructure of detrusor smooth muscle cells was well maintained, and the density of nerve terminals was similar. Western blotting demonstrated reduced contents of calponin and desmin. Smooth muscle α-actin, SM22α and myocardin were unchanged. Activation of strips with exogenous agonists showed that depolarization-induced contraction was preferentially reduced; ATP- and calyculin A-induced contractions were unchanged. Quantitative real time PCR and western blotting demonstrated reduced expression of Cav1.2 (Cacna1c. It is concluded that smooth muscle miRNAs play an important role for detrusor contractility and voiding pattern of unrestrained mice. This is mediated in part via effects on expression of smooth muscle differentiation markers and L-type Ca(2+ channels in the detrusor.

  14. Stress and strain in the contractile and cytoskeletal filaments of airway smooth muscle.

    Science.gov (United States)

    Deng, Linhong; Bosse, Ynuk; Brown, Nathan; Chin, Leslie Y M; Connolly, Sarah C; Fairbank, Nigel J; King, Greg G; Maksym, Geoffrey N; Paré, Peter D; Seow, Chun Y; Stephen, Newman L

    2009-10-01

    Stress and strain are omnipresent in the lung due to constant lung volume fluctuation associated with respiration, and they modulate the phenotype and function of all cells residing in the airways including the airway smooth muscle (ASM) cell. There is ample evidence that the ASM cell is very sensitive to its physical environment, and can alter its structure and/or function accordingly, resulting in either desired or undesired consequences. The forces that are either conferred to the ASM cell due to external stretching or generated inside the cell must be borne and transmitted inside the cytoskeleton (CSK). Thus, maintaining appropriate levels of stress and strain within the CSK is essential for maintaining normal function. Despite the importance, the mechanisms regulating/dysregulating ASM cytoskeletal filaments in response to stress and strain remained poorly understood until only recently. For example, it is now understood that ASM length and force are dynamically regulated, and both can adapt over a wide range of length, rendering ASM one of the most malleable living tissues. The malleability reflects the CSK's dynamic mechanical properties and plasticity, both of which strongly interact with the loading on the CSK, and all together ultimately determines airway narrowing in pathology. Here we review the latest advances in our understanding of stress and strain in ASM cells, including the organization of contractile and cytoskeletal filaments, range and adaptation of functional length, structural and functional changes of the cell in response to mechanical perturbation, ASM tone as a mediator of strain-induced responses, and the novel glassy dynamic behaviors of the CSK in relation to asthma pathophysiology.

  15. β-Citronellol, an alcoholic monoterpene with inhibitory properties on the contractility of rat trachea

    Directory of Open Access Journals (Sweden)

    T.B. Vasconcelos

    2016-01-01

    Full Text Available β-Citronellol is an alcoholic monoterpene found in essential oils such Cymbopogon citratus (a plant with antihypertensive properties. β-Citronellol can act against pathogenic microorganisms that affect airways and, in virtue of the popular use of β-citronellol-enriched essential oils in aromatherapy, we assessed its pharmacologic effects on the contractility of rat trachea. Contractions of isolated tracheal rings were recorded isometrically through a force transducer connected to a data-acquisition device. β-Citronellol relaxed sustained contractions induced by acetylcholine or high extracellular potassium, but half-maximal inhibitory concentrations (IC50 for K+-elicited stimuli were smaller than those for cholinergic contractions. It also inhibited contractions induced by electrical field stimulation or sodium orthovanadate with pharmacologic potency equivalent to that seen against acetylcholine-induced contractions. When contractions were evoked by selective recruitment of Ca2+ from the extracellular medium, β-citronellol preferentially inhibited contractions that involved voltage-operated (but not receptor-operated pathways. β-Citronellol (but not verapamil inhibited contractions induced by restoration of external Ca2+ levels after depleting internal Ca2+ stores with the concomitant presence of thapsigargin and recurrent challenge with acetylcholine. Treatment of tracheal rings with L-NAME, indomethacin or tetraethylammonium did not change the relaxing effects of β-citronellol. Inhibition of transient receptor potential vanilloid subtype 1 (TRPV1 or transient receptor potential ankyrin 1 (TRPA1 receptors with selective antagonists caused no change in the effects of β-citronellol. In conclusion, β-citronellol exerted inhibitory effects on rat tracheal rings, with predominant effects on contractions that recruit Ca2+ inflow towards the cytosol by voltage-gated pathways, whereas it appears less active against contractions elicited by

  16. Presenilin 1 mutation decreases both calcium and contractile responses in cerebral arteries.

    Science.gov (United States)

    Toussay, Xavier; Morel, Jean-Luc; Biendon, Nathalie; Rotureau, Lolita; Legeron, François-Pierre; Boutonnet, Marie-Charlotte; Cho, Yoon H; Macrez, Nathalie

    2017-10-01

    Mutations or upregulation in presenilin 1 (PS1) gene are found in familial early-onset Alzheimer's disease or sporadic late-onset Alzheimer's disease, respectively. PS1 has been essentially studied in neurons and its mutation was shown to alter intracellular calcium (Ca 2+ ) signals. Here, we showed that PS1 is expressed in smooth muscle cells (SMCs) of mouse cerebral arteries, and we assessed the effects of the deletion of exon 9 of PS1 (PS1dE9) on Ca 2+ signals and contractile responses of vascular SMC. Agonist-induced contraction of cerebral vessels was significantly decreased in PS1dE9 both in vivo and ex vivo. Spontaneous activity of Ca 2+ sparks through ryanodine-sensitive channels (RyR) was unchanged, whereas the RyR-mediated Ca 2+ -release activated by caffeine was shorter in PS1dE9 SMC when compared with control. Moreover, PS1dE9 mutation decreased the caffeine-activated capacitive Ca 2+ entry, and inhibitors of SERCA pumps reversed the effects of PS1dE9 on Ca 2+ signals. PS1dE9 mutation also leads to the increased expression of SERCA3, phospholamban, and RyR3. These results show that PS1 plays a crucial role in the cerebrovascular system and the vascular reactivity is decreased through altered Ca 2+ signals in PS1dE9 mutant mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. High-dose benfotiamine rescues cardiomyocyte contractile dysfunction in streptozotocin-induced diabetes mellitus.

    Science.gov (United States)

    Ceylan-Isik, Asli F; Wu, Shan; Li, Qun; Li, Shi-Yan; Ren, Jun

    2006-01-01

    Diabetic cardiomyopathy is characterized by cardiac dysfunction. This study was designed to examine the effect of benfotiamine, a lipophilic derivative of thiamine, on streptozotocin (STZ)-induced cardiac contractile dysfunction in mouse cardiomyocytes. Adult male FVB mice were made diabetic with a single injection of STZ (200 mg/kg ip). Fourteen days later, control and diabetic (fasting plasma glucose > 13.9 mM) mice were put on benfotiamine therapy (100 mg.kg(-1).day(-1) ip) for another 14 days. Mechanical and intracellular Ca2+ properties were evaluated in left ventricular myocytes using an IonOptix MyoCam system. The following indexes were evaluated: peak shortening (PS), time to PS (TPS), time to 90% relengthening (TR90), maximal velocity of shortening/relengthening, resting and rise of intracellular Ca2+ in response to electrical stimulus, sarcoplasmic reticulum (SR) Ca2+ load, and intracellular Ca2+ decay rate (tau). Two- or four-week STZ treatment led to hyperglycemia, prolonged TPS and TR90, reduced SR Ca2+ load, elevated resting intracellular Ca2+ level and prolonged tau associated with normal PS, maximal velocity of shortening/relengthening, and intracellular Ca2+ rise in response to electrical stimulus. Benfotiamine treatment abolished prolongation in TPS, TR90, and tau, as well as reduction in SR Ca2+ load without affecting hyperglycemia and elevated resting intracellular Ca2+. Diabetes triggered oxidative stress, measured by GSH-to-GSSG ratio and formation of advanced glycation end product (AGE) in the hearts. Benfotiamine treatment alleviated oxidative stress without affecting AGE or protein carbonyl formation. Collectively, our results indicated that benfotiamine may rescue STZ-induced cardiomyocyte dysfunction but not AGE formation in short-term diabetes.

  18. The Effect of Substrate Elasticity and Actomyosin Contractility on Different Forms of Endocytosis

    Science.gov (United States)

    Missirlis, Dimitris

    2014-01-01

    Substrate mechanical properties have emerged as potent determinants of cell functions and fate. We here tested the hypothesis that different forms of endocytosis are regulated by the elasticity of the synthetic hydrogels cells are cultured on. Towards this objective, we quantified cell-associated fluorescence of the established endocytosis markers transferrin (Tf) and cholera toxin subunit B (CTb) using a flow-cytometry based protocol, and imaged marker internalization using microscopy techniques. Our results demonstrated that clathrin-mediated endocytosis of Tf following a 10-minute incubation with a fibroblast cell line was lower on the softer substrates studied (5 kPa) compared to those with elasticities of 40 and 85 kPa. This effect was cancelled after 1-hour incubation revealing that intracellular accumulation of Tf at this time point did not depend on substrate elasticity. Lipid-raft mediated endocytosis of CTb, on the other hand, was not affected by substrate elasticity in the studied range of time and substrate elasticity. The use of pharmacologic contractility inhibitors revealed inhibition of endocytosis for both Tf and CTb after a 10-minute incubation and a dissimilar effect after 1 hour depending on the inhibitor type. Further, the internalization of fluorescent NPs, used as model drug delivery systems, showed a dependence on substrate elasticity, while transfection efficiency was unaffected by it. Finally, an independence on substrate elasticity of Tf and CTb association with HeLa cells indicated that there are cell-type differences in this respect. Overall, our results suggest that clathrin-mediated but not lipid-raft mediated endocytosis is potentially influenced by substrate mechanics at the cellular level, while intracellular trafficking and accumulation show a more complex dependence. Our findings are discussed in the context of previous work on how substrate mechanics affect the fundamental process of endocytosis and highlight important

  19. Chelidonium majus and its effects on uterine contractility in a perfusion model.

    Science.gov (United States)

    Kuenzel, Julian; Geisler, Klaudija; Strahl, Olga; Grundtner, Philipp; Beckmann, Matthias W; Dittrich, Ralf

    2013-07-01

    The herbal agent celandine is thought to have mainly spasmolytic effects, but in the uterus it is regarded as promoting contractions, which can offer promising and innovative options for optimizing artificial reproduction. The aim of the present study was to investigate the effect of celandine on the uterine muscle, using a perfusion model of swine uteri. Sixteen swine uteri were perfused with Krebs-Ringer solution. Celandine (Chelidonium, Paverysat; Johannes Bürger Ysatfabrik Ltd., Bad Harzburg, Germany) was administered at increasing dosages. Intrauterine pressure (IUP) was recorded using an intrauterine double-chip microcatheter (Urobar 8 DS-F, Raumedic, Rehau AG & Co., Rehau, Germany). Differences in pressure (ΔP) and area under the curve (ΔAUC) after drug administration in the uterine body and uterine horn in the various dilution series were noted. A paired Student's t-test was used to evaluate differences between groups, with significance set at P<0.05. A significant initial increase in uterine activity was visible at each dosage. Inhibition of uterine activity was seen over longer periods of 5 and 10 min, particularly for a medium-dose range of 1-2mg/ml. At a dosage of 2mg/ml in particular, celandine almost always led to significant values. Following intra-arterial administration in a swine uterus perfusion model, celandine initially causes a significant increase in contractility, which is followed over time by a relaxation phase. This suggests interesting hypotheses on whether Chelidonium majus might be used to promote targeted sperm transport. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. The effects of watermelon (Citrullus lanatus) extracts and L-citrulline on rat uterine contractility.

    Science.gov (United States)

    Munglue, Phukphon; Eumkep, Graingsak; Wray, Susan; Kupittayanant, Sajeera

    2013-04-01

    In uterine smooth muscle, the effects of watermelon and its citrulline content are unknown. The aims of this study were therefore, to determine the effects of watermelon extract and citrulline on the myometrium and to investigate their mechanisms of action. The effects of extracts of watermelon flesh and rind and L-citrulline (64 μmol/L) were evaluated on 3 types of contractile activity; spontaneous, those elicited by potassium chloride (KCl) depolarization, or oxytocin (10 nmol/L) application in isolated rat uterus. Inhibitors of nitric oxide (NO) and its mechanisms of action, N ω-Nitro-L-arginine methyl ester hydrochloride (L-NAME, 100 μmol/L), LY83583 (1 μmol/L), and tetraethylamonium chloride (5 mmol/L), as well as Ca signaling pathways, were determined. Both flesh and rind extracts significantly decreased the force produced by all 3 mechanisms, in a dose-dependent manner. The extracts could also significantly decrease the force under conditions of sustained high Ca levels (depolarization and agonist) and when the force was produced only by sarcoplasmic reticulum (SR) Ca release. L-citrulline produced the same effects on force as watermelon extracts. With submaximal doses of extract, the additive effects of L-citrulline were found. The inhibitory effects of extracts and L-citrulline were reversed upon the addition of NO inhibitors, and pretreatment of tissues with these inhibitors prevented the actions of both extracts and L-citrulline. Thus, these data show that watermelon and citrulline are potent tocolytics, decreasing the force produced by calcium entry and SR release and arising by different pathways, including oxytocin stimulation. Their major mechanism is to stimulate the NO-cyclic guanosine monophosphate (cGMP) relaxant pathway.

  1. Selección de bacterias con capacidad degradadora de hidrocarburos aisladas a partir de sedimentos del Caribe colombiano.

    OpenAIRE

    Narváez-Florez, S.; Gómez, M.L.; Martínez, M.M.

    2008-01-01

    A partir de sedimentos del Caribe colombiano se realizaron 31 aislamientos bacterianos en medio mínimo de sales suplementado con hidrocarburos (ACPM o petróleo crudo) como única fuente de carbono. Las cepas aisladas se sometieron a pruebas de selección en diferentes concentraciones de hidrocarburos y se escogieron once de ellas tolerantes al crudo y ACPM en un ámbito del 1-8% v/v. Posteriormente, con las cepas seleccionadas, se conformó un cultivo bacteriano mixto y se evaluó su capacidad de ...

  2. SELECCIÓN DE BACTERIAS CON CAPACIDAD DEGRADADORA DE HIDROCARBUROS AISLADAS A PARTIR DE SEDIMENTOS DEL CARIBE COLOMBIANO

    OpenAIRE

    Narváez-Flórez, Silvia; L. Gómez, Martha; Martínez, María M.

    2008-01-01

    A partir de sedimentos del Caribe colombiano se realizaron 31 aislamientos bacterianos en medio mínimo de sales suplementado con hidrocarburos (ACPM o petróleo crudo) como única fuente de carbono. Las cepas aisladas se sometieron a pruebas de selección en diferentes concentraciones de hidrocarburos y se escogieron once de ellas tolerantes al crudo y ACPM en un ámbito del 1-8% v/v. Posteriormente, con las cepas seleccionadas, se conformó un cultivo bacteriano mixto y se evaluó su capacidad de ...

  3. Capacidad de afronte y autoeficacia en estudiantes durante las practicas pre profesionales de psicología 2015

    OpenAIRE

    Sánchez Ortega, Carmen Doris

    2016-01-01

    La presente investigación tuvo como objetivo general de determinar si existe relación entre capacidad de afronte y autoeficacia en estudiantes durante las practicas pre profesionales de psicología. La investigación fue de tipo sustantiva con un nivel descriptivo, correlacional con un enfoque cuantitativo, diseño no experimental y transversal. La población estuvo conformada por 135 alumnos universitarios que se encontraban realizando prácticas pre profesionales de la carrera ...

  4. El principio de capacidad económica en la jurisprudencia tributaria comparada de Chile y España

    OpenAIRE

    Fernández Amor,José Antonio; Masbernat,Patricio

    2011-01-01

    El presente trabajo busca identificar las concepciones que la jurisprudencia constitucional chilena y española tienen en relación al principio de capacidad económica como criterio jurídico de distribución de las cargas tributarias. Por otro lado, intenta determinar a su respecto las semejanzas que se presentan en ambos sistemas jurídicos. La conclusión es que, no obstante las diferentes inspiraciones de los constituyentes en España y Chile en el ámbito tributario, se puede apreciar una conver...

  5. Evaluación de la capacidad antioxidante por el Método Frap de un posible alimento funcional

    OpenAIRE

    Gomero Ostos, Néstor

    2013-01-01

    El presente trabajo tiene como objetivo determinar si la incorporación de brócoli deshidratado en la formulación de un producto de panificación le permite mostrar a esta última capacidad antioxidante de tal manera que le pueda considerar como un alimento funcional. Existen evidencias epidemiológicas de una asociación inversa entre :consumo de brócoli, otras crucíferas (col; coliflor y col bruselas) y riesgo de cáncer, las propiedades anticancerígenas de estos vegetales se han atribuido a ...

  6. Innovation capability and organizational resources configuration Capacidad de innovación y configuración de recursos organizativos

    Directory of Open Access Journals (Sweden)

    Liliana Herrera

    2009-07-01

    Full Text Available The main purpose of this article is to contribute to a better understanding of the organizational sources pertaining to continuous innovation. This work identifies a set of best practices, which once integrated, create the innovative activities that help organizations to acquire a continuous innovation capability by means of the development of new products. Furthermore, in an effort to understand how the innovation capacity is created, based on the dynamic capability theory, a conceptual model is presented in this study. This model shows that the innovation capability is the result of four processes: knowledge creation, knowledge absorption, knowledge integration, and knowledge reconfiguration. These processes are leveraged by four kinds of resources: human capital, structures and systems, leadership, and company culture. Companies applying this model can identify and restructure the most important organizational actions in order to achieve a continuous innovation process. Finally, identification of best practices and model validation are carried out by means of an exploratory case study, which is applied to two technology based organizations of the audiovisual sector.El propósito de este artículo es contribuir a un mejor entendimiento de los recursos involucrados en el proceso de innovación continua en las empresas. En este trabajo se identifican un conjunto de buenas prácticas, las cuales integradas, forman actividades innovadoras que ayudan a las organizaciones a adquirir la capacidad para innovar continuamente por medio de los proyectos de desarrollo de nuevos productos. Además, en un esfuerzo por comprender como esta conformada la capacidad de innovación, en esta investigación se presenta un modelo conceptual basado en la perspectiva de las capacidades dinámicas, el cual muestra esta capacidad como el resultado de cuatro procesos: creación de conocimiento, absorción de conocimiento, integración de conocimiento y reconfiguraci

  7. LAS CAPACIDADES TECNOLÓGICAS COMO BASE PARA EL DESARROLLO (TECHNOLOGICAL CAPABILITIES AS A BASIS FOR DEVELOPMENT

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    Carvajal Villaplana Álvaro

    2010-04-01

    Full Text Available Resumen:En este artículo interesa determinar la estructura lógica del concepto de capacidades tecnológicas para establecer las características y los componentes más relevantes, esto con la intención de proponer una definición filosófica a partir de las ideas de capacidades y funcionamientos de Amartya Sen y del concepto de disposiciones de Gilbert Ryle. Se trata de una ampliación o aplicación de esas nociones a la idea de capacidades tecnológicas con el fin de obtener dicho concepto operativo y apropiado. El estudio se lleva a cabo, porque la noción de capacidades tecnológicas es muy utilizada en diversos textos de economía, administración, tecnología y filosofía, pero sin que se las defina apropiadamente ni se les fundamente filosóficamente. La investigación en la que se sustenta el artículo se realizó en el año 2005 con un enfoque de análisis inscrito en la tradición filosófica analítica.Abstract:In this work I am interested in determining the logical structure of the concept of technological capabilities to establish their characteristics and components. This is done with the intention of proposing an operative definition of such a notion. For this purpose I proceed to establish its theoretical foundation, inspired in Amartya Sen’s conception of capability and operation, as well as in Ryle's concept of disposition. It is an amplification or application from those notions to the idea of technological capability in order to obtain an operative and appropriate notion. An exploration of the notion of tecnological capabilities seems very timely because of its widespread use in economics, business administration and philosophy, areas in which both a clear definition and a theoretical explanation are usually missing. The research for this paper took place in 2005, when its author was working for his Ph.D. at the Carlos III University in Madrid. Our approach here is typical of the analytical tradition in philosophy.

  8. As capacidades de inovação em Startups : um estudo no Vale do Silício

    OpenAIRE

    Andréia Cristina Dullius

    2016-01-01

    Startups surgem com o intuito de explorar comercialmente uma ideia de potencial inovador. Para isso, necessitam de um conjunto de capacidades técnicas e de negócios, alocando recursos de modo eficiente para obter um produto com valor de mercado. Elas necessitam, portanto, tornar-se firmas e executar um modelo de negócios. Nesse processo, muitas startups fracassam, enquanto outras atingem um bom desempenho e conseguem realizar a oferta pública de ações (IPO), ou mesmo vender o negócio. Torna-s...

  9. Analise de alternativas de expansão de capacidade dos sistemas urbanos de abastecimento de agua em Santa Catarina

    OpenAIRE

    Jungles, Antonio Edesio

    1994-01-01

    Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnologico Para analisar a expansão de capacidade dos sistemas de abastecimento de água foi desenvolvido uma metodologia que envolveu os custos de construção da cada componente que configura o sistema de abastecimento de água e os de operação divididos em despesas com pessoal, energia elétrica, materiais de tratamento e outras despesas do sistema. Análises de regressão múltipla linear e não linear foram utilizadas para o aj...

  10. Modelo de gestión del conocimiento para medir la capacidad productiva en grupos de investigación

    OpenAIRE

    Fredy Eduardo Vásquez Rizo

    2010-01-01

    Las organizaciones actuales manejan y producen numerosos datos e información. Muchos de estos elementos son subutilizados o despreciados al carecer de mecanismos y/o procesos para transformarlos en conocimiento útil. El estudio que se expone se centra en datos e información relacionados con la capacidad productiva de los grupos de investigación de una universidad colombiana (Universidad Autónoma de Occidente- UAO), utilizándolos para la generación de conocimiento valioso, a través de la const...

  11. Modelo de gestión del conocimiento para medir la capacidad productiva en grupos de investigación

    OpenAIRE

    Vásquez Rizo, Fredy Eduardo

    2010-01-01

    Las organizaciones actuales manejan y producen numerosos datos e información. Muchos de estos elementos son subutilizados o despreciados al carecer de mecanismos y/o procesos para transformarlos en conocimiento útil. El estudio que se expone se centra en datos e información relacionados con la capacidad productiva de los grupos de investigación de una universidad colombiana (Universidad Autónoma de Occiden-te-UAO), utilizándolos para la generación de conocimiento valioso, a través de la const...

  12. Influencia del programa preventivo promocional en salud escolar y el desarrollo de capacidades en higiene personal en estudiantes

    OpenAIRE

    Salvador Esquivel, Nilda Elizabeth

    2015-01-01

    Objetivo: Determinar la influencia del programa preventivo promocional en salud escolar en el desarrollo de capacidades en higiene personal en estudiantes del primer grado de educación primaria de la Institución Educativa N°1211 José María Arguedas, Santa Anita, 2013. Material y métodos: Estudio cuantitativo, de tipo cuasi experimental, de corte transversal, prospectivo. La población fue de 56 estudiantes del 1er. grado A (grupo experimental) y B (grupo control). El estudio tuvo una duraci...

  13. Avaliação da Capacidade de Decisão em Psiquiatria de Ligação

    Directory of Open Access Journals (Sweden)

    Filipe Lopes Vicente

    2017-03-01

    Full Text Available Introdução: Entre as funções do psiquiatra de ligação, encontra-se a avaliação da capacidade de decidir. Esta envolve a capacidade de fazer escolhas de forma autónoma e surge de forma relevante na prática clínica diária como pré-condição ao consentimento informado. Objetivos: Os autores pretendem rever o pro- cesso subjacente à avaliação da capacidade de decisão, assim como outra informação relevante publicada a este respeito. Métodos: Revisão não sistemática da literatura através da pesquisa eletrónica nos motores de busca Medline/Pubmed. Resultados: A capacidade de decidir apenas pode ser avaliada relativamente a uma decisão em particular, sendo que o seu resultado não é necessariamente estável ao longo do tempo. Da mesma forma, não existe nenhum diagnóstico que permita concluir, por si só, pela incapacidade para decidir ou que possibilite prescindir da sua avaliação. Depende de vários fatores: conteúdo, forma do pensa- mento e funções cognitivas. Pode igualmente ser influenciada pelo nível de instrução do indivíduo,  traços  da  personalidade,  estados emocionais/mecanismos de coping ou fatores circunstanciais. Qualquer  médico  deverá  estar  habilitado para  a  realização  desta  avaliação.  O  psiquiatra  de  ligação  deve  ser  envolvido  perante  a  suspeita  de  doença  mental  capaz de  prejudicar  a  capacidade  de  consentir ou  perante  a  necessidade  de  validar  uma avaliação já realizada. Appelbaum e Grisso propuseram  uma  avaliação  sistematizada segundo os seguintes critérios: a comunicação da escolha, b compreensão, c apreciação  e  d  processo  de  decisão  racional/ raciocínio.  Numa  tentativa  de  minimizar diferenças entre avaliadores, foram desenvolvidos vários instrumentos de avaliação, entre os quais se destaca a MacArthur Competence  Assessment  Tool.  Particularmente nos doentes com d

  14. Estudio de la capacidad de los hidroxiapatitos como reactivos para la eliminación de metales

    OpenAIRE

    Toribio Jiménez, Eva

    2015-01-01

    El Trabajo de Fin de Grado se ha centrado en el estudio de la capacidad que tienen los hidroxiapatitos, como materiales reactivos para eliminar metales de disoluciones acuosas. En el mismo, se evaluaran diferentes formas de hidroxiapatitos, tanto sintetizados siguiendo rutas a alta temperatura y a temperatura ambiente, así como un tipo de hidroxiapatita natural de origen animal y se han elegido dos metales pesados de interés ambiental, bien por su impacto sobre la salud humana o sobre los ...

  15. Problemas de competencia en la asignación de la capacidad de los aeropuertos. El Caso Argentino

    OpenAIRE

    Briggs, María Cristina; Petrecolla, Diego

    2001-01-01

    Este trabajo estudia el papel que juegan los mecanismos de asignación de la capacidad limitada de los aeropuertos (slots) en Aeroparque sobre la competencia en el mercado aéreo de cabotaje. Este trabajo encuentra que el mecanismo actual de reuniones utilizado en Aeroparque dificulta la entrada de nuevos competidores a las rutas y produce asignaciones ineficientes de los slots. Se propone entonces un mecanismo de subasta inicial seguida de un mercado de slots que permitirá reforzar el proceso ...

  16. Um ambiente virtual para o planejamento de capacidade de ambientes voltados ao comércio eletrônico

    OpenAIRE

    Costa, Eduardo Dockhron da

    2005-01-01

    Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação. Um dos grandes desafios existentes no comércio eletrônico é a correta implementação de sua infra-estrutura. Os componentes de hardware e software estão, com o passar do tempo, sofrendo um grande incremento de capacidade e velocidade de processamento. Aumenta-se, em paralelo, o custo para se obter tecnologia de ponta. Nessa escala de crescimento, os nív...

  17. Capacidad de fijación y adsorción de cloruros en morteros elaborados con distintos cementos

    OpenAIRE

    Villagrán Zaccardi, Yuri Andrés; Matiasich, Cecilia

    2004-01-01

    La retención de iones cloruro por parte de los hidratos del cemento se puede producir por dos mecanismos: por adsorción superficial, principalmente en la fase de silicato hidratado; y por fijación, mayormente en la fase de aluminato hidratado. Este trabajo tiene por objetivo determinar las capacidades de adsorción y de fijación de cloruros en morteros con una misma relación a/c, realizados con distintos cementos (normal, fillerizado, compuesto y de alto horno). El estudio comprende dos series...

  18. Espinha bífida aberta: achados ultra-sonográficos e presença de contrações uterinas na predição da evolução motora neonatal Open spina bifida: antenatal ultrasound findings and uterine contractions as predictors of the neonatal neuromotor outcome

    Directory of Open Access Journals (Sweden)

    Wagner Jou Hisaba

    2003-07-01

    Full Text Available OBJETIVO: avaliar a influência das alterações ultra-sonográficas pré-natais e das contrações uterinas de trabalho de parto na evolução motora neonatal em fetos portadores de espinha bífida aberta. MÉTODOS: foram analisados fetos portadores de espinha bífida aberta. Estes fetos foram acompanhados nos serviços de Medicina Fetal do Hospital São Paulo (Universidade Federal de São Paulo e do Hospital e Maternidade Santa Joana. Todos os partos foram realizados nestes serviços e a avaliação neonatal foi realizada pela equipe de Neurocirurgia comum a ambas as instituições Foi observada a influência das alterações ultra-sonográficas (macrocrania, microcrania, nível da falha de fechamento da coluna, pé torto e tipo de apresentação fetal na força muscular de membros inferiores no período neonatal. Foi analisada, também, a influência das contrações uterinas sobre a movimentação dos membros inferiores. Todos os partos foram realizados por cesárea. Foram utilizados os testes de c² e Fisher para comparações categóricas, com pPURPOSE: to determine whether prenatal sonographic findings and uterine contractions can predict neonatal motor outcome in fetuses with open spina bifida. METHODS: we evaluated retrospectively 53 fetuses with open spina bifida from 1993 to 2001. These fetuses were born and followed-up at the fetal medicine units of the Hospital São Paulo ("Universidade Federal de São Paulo" and the "Hospital Santa Joana". The influence of the alterations observed through ultrasound scan on neonatal muscular strength (macrocrania, microcrania, level of the spinal column opening, clubfoot and type of fetus position was evaluated. The influence of uterine contractions on neonatal motor outcome was also evaluated. All deliveries were made through cesarian section. c² and Fisher tests were used for categorical comparisons. A p<0.05 was considered significant. RESULTS: Fifty-three cases of isolated open spina bifida

  19. Proposta de utilização da técnica de contagem como preditor da capacidade vital lenta em indivíduos hospitalizados

    Directory of Open Access Journals (Sweden)

    Aline Cabral Palmeira

    2015-04-01

    Full Text Available OBJETIVO:avaliar se existe correlação entre a capacidade vital lenta e o tempo máximo de fonação, mais especificamente pela técnica de contagem numérica e se é possível a partir do tempo máximo de fonação estimar a capacidade vital lenta em indivíduos hospitalizados.MÉTODOS:trata-se de um estudo do tipo transversal, crossover e a escolha das técnicas (espirometria e técnica de contagem numérica foram realizadas de forma randomizada (sorteio simples. A capacidade vital lenta foi mensurada por meio da espirometria e o tempo máximo de fonação foi avaliado a partir da técnica de contagem numérica.RESULTADOS:participaram da pesquisa 221 pacientes hospitalizados. Foi verificada uma correlação positiva entre a capacidade vital lenta e o tempo máximo de fonação avaliados de forma absoluta (r = 0,75; p < 0,001 e relativa (r = 0,76; p < 0,001. A partir da regressão linear simples dos dados, foram verificados equações das retas analisadas de forma absoluta, Capacidade vital lenta = 55 Técnica de contagem numérica + 735 (r2= 0,56; p < 0,0001 e relativa, Capacidade vital lenta = 0,84 Técnica de contagem numérica + 14 (r2= 0,57; p < 0,0001.CONCLUSÕES:os resultados obtidos nesta pesquisa mostraram uma boa correlação entre as técnicas avaliadas, sendo possível estimar a capacidade vital lenta a partir da técnica de contagem numérica em indivíduos hospitalizados.

  20. Upregulation of contractile endothelin type B receptors by lipid-soluble cigarette smoking particles in rat cerebral arteries via activation of MAPK

    International Nuclear Information System (INIS)

    Sandhu, Hardip; Xu, Cang Bao; Edvinsson, Lars

    2010-01-01

    Cigarette smoke exposure increases the risk of stroke. However, the underlying molecular mechanisms are poorly understood. Endothelin system plays key roles in the pathogenesis of stroke. The present study was designed to examine if lipid-soluble (dimethyl sulfoxide-soluble) cigarette smoke particles (DSP) induces upregulation of contractile endothelin type B (ET B ) receptors in rat cerebral arteries and if activation of mitogen activated protein kinase (MAPK) and nuclear factor-kappaB (NF-κB) mediate the upregulation of contractile endothelin receptors in the cerebral arteries. Rat middle cerebral arteries were isolated and organ cultured in serum free medium for 24 h in the presence of DSP with or without specific inhibitors: MEK specific (U0126), p38 specific (SB202190), JNK specific (SP600125), NF-κB specific (BMS-345541) or (IMD-0354), transcription inhibitor (actinomycin D), or translation blocker (cycloheximide). Contractile responses to the ET B receptor agonist sarafotoxin 6c were investigated by a sensitive myograph. The expression of the ET B receptors were studied at mRNA and protein levels using quantitative real time PCR and immunohistochemistry, respectively. Results show that organ culture per se induced transcriptional upregulation of contractile ET B receptors in the cerebral vascular smooth muscle cells. This upregulation was further increased at the translational level by addition of DSP to the organ culture, but this increase was not seen by addition of nicotine or water-soluble cigarette smoke particles to the organ culture. The increased upregulation of contractile ET B receptors by DSP was abrogated by U0126, SP600125, actinomycin D, and cycloheximide, suggesting that the underlying molecular mechanisms involved in this process include activation of MEK and JNK MAPK-mediated transcription and translation of new contractile ET B receptors. Thus, the MAPK-mediated upregulation of contractile ET B receptors in cerebral arteries might be a

  1. A influência da capacidade de aprendizado, da criatividade organizacional, da orientação empreendedora internacional, da capacidade tecnológica e da capacidade de reconfiguração na habilidade em desenvolvimento de novos produtos

    OpenAIRE

    Panizzon, Mateus

    2016-01-01

    Em um contexto de globalização, com a intensificação do desenvolvimento econômico baseado em conhecimento, inovação e criatividade como fontes de valor agregado, empresas buscam continuamente vantagem competitiva sustentável em ambientes de mudança e turbulência. Deste modo, a agenda de pesquisa teórica nos campos das Capacidades Dinâmicas Baseadas em Conhecimento, Criatividade Organizacional, Orientação Empreendedora Internacional e Desenvolvimento de Novos Produtos motiva novos estudos e re...

  2. Capacidad de compra del salario mínimo mensual y estado social de derecho en Colombia, 1983-2013

    Directory of Open Access Journals (Sweden)

    José Gersaín Cortés Pinto

    2013-07-01

    Full Text Available Este artículo analiza el comportamiento de la capacidad de compra del salario mínimo mensual legal vigente (SMMLV en Colombia para el periodo 1983-2013, a la luz de las implicaciones derivadas del paso del régimen de un Estado de derecho al de un Estado social de derecho, introducido por la Constitución Política Nacional de 1991 y su antecedente inmediato en materia laboral: la Ley 50 de 1990. Inicialmente se hace una caracterización del perfil institucional y técnico del proceso de toma de decisiones sobre el reajuste anual del SMMLV con sus correspondientes resultados. En la segunda sección se analiza el comportamiento del SMMLV de manera comparada con el de la inflación. La tercera sección se dedica al análisis de la capacidad de compra (perdida o ganada por los trabajadores en el proceso, a través de un indicador construido con este propósito específico. Al final se obtienen algunas conclusiones y recomendaciones.

  3. Relación entre la incapacidad laboral y el uso del Índice de Capacidad de Trabajo

    Directory of Open Access Journals (Sweden)

    Ana Virginia Díaz Bethencourt

    Full Text Available Introducción: Con el envejecimiento de la población existe una creciente preocupación por la sostenibilidad a largo plazo de los sistemas de protección social y de pensiones. Los problemas de salud y discapacidades son importantes causas de las salidas anticipadas del puesto de trabajo. Objetivo: Nuestro estudio se basa en revisar el uso del Índice de Capacidad de Trabajo o Work Ability Index (WAI como herramienta para medir la capacidad laboral y como pronóstico de desarrollo de la incapacidad laboral. Método: Se ha realizado la búsqueda bibliográfica de artículos publicados entre 2004-Enero 2015, en las siguientes bases de datos: PubMed, Osh Update, WOS, Cochrane, Lilacs, Ibecs, Scopus y Google Scholar. Resultados: Tras aplicar los criterios de inclusión y exclusión, se seleccionan 5 artículos. Conclusión: Se sugiere la existencia de una relación entre el uso del WAI y su valor predictivo para recibir la pensión por incapacidad. Debiéndose incluir también el entorno social y económico de los trabajadores. Se deberían realizar más estudios que incluyan otras categorías laborales que no impliquen sólo sobrecarga física.

  4. AVALIAÇÃO DA CAPACIDADE FUNCIONAL DE IDOSOS EM UMA COMUNIDADE DO MUNICÍPIO DE MORENO – PE

    Directory of Open Access Journals (Sweden)

    MARIA EMÍLIA VILELA TENÓRIO

    2006-01-01

    Full Text Available El objetivo de este estudio fue evaluar la capacidad funcional de las personas mayores. Es una investigación descriptiva, realizada en la Comunidad Alto das Estrelas, Moreno-PE, con 30 personas mayores registradas en PSF. Para recoger los datos necesarios se usó un formulario constando de tres partes: 1 identificación de la persona mayor, 2 Escala de Actividades de Vida Diaria (AVD y Escala de Actividades Instrumentales de Vida Diaria (AIVD, 3 identificación de las causas de las incapacidades de la persona mayor, aplicado durante la visita domiciliar. Los resultados obtenidos mencionaron: 16 mujeres y 14 hombres; edad entre 60 y 70 años; agricultores casados, jubilados o pensionistas; no alfabetizados; viviendo con hijos y nietos, ayudándoles; realizando actividades de ocio y actividades religiosas. Las quejas principales sobre la salud: la falta de memoria (“el olvido” y las alteraciones visuales. Se descubrieron tres personas mayores que dependían de ayuda, debido a secuela decurrente de Accidente Vascular Cerebral, enfermedad óseo-articular y enfermedad psiquiátrica. Se elaboró una propuesta de rehabilitación y mantenimiento de la capacidad funcional de las personas mayores atendidas en USF.

  5. Desarrollo de habilidades, hábitos y capacidades en la licenciatura en cultura física

    Directory of Open Access Journals (Sweden)

    Jorge Luis Cobas Portuondo

    2011-09-01

    Full Text Available EL siguiente trabajo está destinado a resolver el problema de aprendizaje en nuestra SUM. Para ello, el mismo se basa en la elaboración de un folleto que contiene orientaciones metodológicas para el desarrollo de habilidades, hábitos y capacidades siendo aplicable a la carrera de Licenciatura en Cultura Física. Se realiza un análisis bibliográfico donde se plantean los fundamentos que sustentan el desarrollo y formación de habilidades, hábitos y capacidades en forma de una recopilación de los temas más importante de la misma. La evaluación de los resultados obtenidos en la validación del producto científico durante el curso escolar 2008-2009 permitió obtener juicios de valor sobre su funcionalidad evidenciándose cambios en los resultados, aproximándose al estado deseado. Por estas razones, los resultados de la aplicación de este producto corroboran la pertinencia social del mismo, con respecto a las necesidades, expectativas y características de los docentes y estudiantes, por lo que puede avalarse la satisfacción del objetivo propuesto y por consiguiente su contribución al desempeño profesional.

  6. La internacionalización de la empresa a través del enfoque de recursos y capacidades

    Directory of Open Access Journals (Sweden)

    Jiménez Palmero, Alfredo

    2008-11-01

    Full Text Available La internacionalización de la empresa constituye un fenómeno de especial relevancia dadas las controvertidas repercusiones que las actividades de las empresas multinacionales tienen tanto en su país de origen como de destino. El enfoque de recursos y capacidades ha sido un marco teórico muy empleado en la investigación científica para tratar de explicar el porqué y el cómo de esta importante decisión estratégica. El presente trabajo pretende ofrecer una revisión bibliográfica de algunos de los trabajos de referencia que han analizado la relación entre la dotación de recursos y capacidades y la estrategia, el método de entrada y el empleo de expatriados por parte de las empresas que han acometido el proceso de internacionalización.

  7. Capacidad antioxidante y contenido de fenoles totales de Hyptis spp., P. Heptaphyllum, T. Panamensis, T. Rhoifolia, y Ocotea sp.

    Directory of Open Access Journals (Sweden)

    Geovanna Tafurt García

    2015-05-01

    Full Text Available En este trabajo se evaluó la posible correlación entre las actividades antioxidantes, el contenido de fenoles totales (CFT y la composición química de Lamiaceae (H. conferta, H. dilatata, H. mutabilis, H. suaveolens, Burseraceae (P. heptaphyllum, T. rhoifoila, T. panamensis y Lauraceae (Ocotea sp.. Para los extractos etanólicos obtenidos por maceración en frio y evaporación a sequedad, la Capacidad Antioxidante Equivalente al Trolox o la Actividad Antioxidante Total (AAT, fueron determinadas mediante un ensayo colorimétrico con el catión radical ABTS, la Concentración Efectiva (EC50 fue evaluada con el radical DPPH, y el Contenido de Fenoles Totales (CFT, fue establecido mediante el método de Folin-Ciocalteu. Tanto la AAT como la EC50 estuvieron altamente correlacionados con el CFT. Las cortezas de T. rhoifolia y T. panamensis mostraron las capacidades antioxidantes más altas. Las Burseraceae spp. mostraron los TPC más altos y las Lamiaceae (Hyptis spp. mostraron los TPC más bajos.

  8. Capacidad de esfuerzo en snowboarders: diferencias individuales en una prueba de máximo esfuerzo en half-pipe

    Directory of Open Access Journals (Sweden)

    J. Arruza

    2005-01-01

    Full Text Available El propósito de esta investigación es analizar y valorar la capacidad de realizar esfuerzos de los snowboarders, en una prueba específica. Evaluaremos dicha capacidad de trabajo individual a través de la Frecuencia cardiaca (FC, del Esfuerzo Percibido (REP y del Nivel de Fatiga Percibida (NFP, en la modalidad de Half-Pipe. Se trata de un estudio descriptivo, valorativo y correlacional de diseño cuasiexperimental unifactorial multivariado, con una muestra de n=5 sujetos, que constituyen la totalidad del equipo Olímpico español de Snowboard. La prueba diseñada ad hoc se ha realizado a 3.000 m. en el glaciar de Tignes. Las conclusiones de este estudio demuestran 1 que es posible realizar una investigación de campo en la que se cuantifique la intensidad de la tarea, y 2 que para valorar el esfuerzo debemos combinar variables fisiológicas y psicológicas. Finalmente se plantea la importancia del Nivel de Fatiga Percibida, como instrumento predictivo en el proceso de toma de decisiones.

  9. Palmitate diet-induced loss of cardiac caveolin-3: a novel mechanism for lipid-induced contractile dysfunction.

    Directory of Open Access Journals (Sweden)

    Catherine J Knowles

    Full Text Available Obesity is associated with an increased risk of cardiomyopathy, and mechanisms linking the underlying risk and dietary factors are not well understood. We tested the hypothesis that dietary intake of saturated fat increases the levels of sphingolipids, namely ceramide and sphingomyelin in cardiac cell membranes that disrupt caveolae, specialized membrane micro-domains and important for cellular signaling. C57BL/6 mice were fed two high-fat diets: palmitate diet (21% total fat, 47% is palmitate, and MCT diet (21% medium-chain triglycerides, no palmitate. We established that high-palmitate feeding for 12 weeks leads to 40% and 50% increases in ceramide and sphingomyelin, respectively, in cellular membranes. Concomitant with sphingolipid accumulation, we observed a 40% reduction in systolic contractile performance. To explore the relationship of increased sphingolipids with caveolins, we analyzed caveolin protein levels and intracellular localization in isolated cardiomyocytes. In normal cardiomyocytes, caveolin-1 and caveolin-3 co-localize at the plasma membrane and the T-tubule system. However, mice maintained on palmitate lost 80% of caveolin-3, mainly from the T-tubule system. Mice maintained on MCT diet had a 90% reduction in caveolin-1. These data show that caveolin isoforms are sensitive to the lipid environment. These data are further supported by similar findings in human cardiac tissue samples from non-obese, obese, non-obese cardiomyopathic, and obese cardiomyopathic patients. To further elucidate the contractile dysfunction associated with the loss of caveolin-3, we determined the localization of the ryanodine receptor and found lower expression and loss of the striated appearance of this protein. We suggest that palmitate-induced loss of caveolin-3 results in cardiac contractile dysfunction via a defect in calcium-induced calcium release.

  10. LET-99 functions in the astral furrowing pathway, where it is required for myosin enrichment in the contractile ring.

    Science.gov (United States)

    Price, Kari L; Rose, Lesilee S

    2017-09-01

    The anaphase spindle determines the position of the cytokinesis furrow, such that the contractile ring assembles in an equatorial zone between the two spindle poles. Contractile ring formation is mediated by RhoA activation at the equator by the centralspindlin complex and midzone microtubules. Astral microtubules also inhibit RhoA accumulation at the poles. In the Caenorhabditis elegans one-cell embryo, the astral microtubule-dependent pathway requires anillin, NOP-1, and LET-99. LET-99 is well characterized for generating the asymmetric cortical localization of the Gα-dependent force-generating complex that positions the spindle during asymmetric division. However, whether the role of LET-99 in cytokinesis is specific to asymmetric division and whether it acts through Gα to promote furrowing are unclear. Here we show that LET-99 contributes to furrowing in both asymmetrically and symmetrically dividing cells, independent of its function in spindle positioning and Gα regulation. LET-99 acts i