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1.
Cir Pediatr ; 30(1): 28-32, 2017 Jan 25.
Artículo en Español | MEDLINE | ID: mdl-28585787

RESUMEN

OBJECTIVE: The defecation disorders represents the 3% of consultations in pediatrics patients. Our goal was to demonstrate the effectiveness and efficiency of the reeducation of the defecation maneuver through home training in patients with encopresis and sphincter dyssynergia. MATERIAL AND METHODS: Study of patients with fecal incontinence treated with home training at our center between 2014-2015. Anorectal manometry was performed and was valued defecation maneuver by expulsion of rectal probe with or without the ball. Daily sessions were performed using a Foley catheter (18-20Fr.) with progressive filling of the balloon, maximum 20cc. The response to the treatment was assessed in terms of episodes of soiling. RESULTS: Seven patients (6 males and 1 female) with a mean age of 9.7 years (range, 5-15) were included; two patients with anorectal malformation history, 1 Hirschsprung disease, 1 sacrococcygeal teratoma and 3 functional encopresis. Three patients had soiling episodes daily and 4 patients frequently. The mean basal pressure of anal channel was 32.34mmHg (range, 11.74-50.75) with negative defecation maneuver in 2 cases, deficient in 3 and dyssynergic in 2 patients. The mean time of biofeedback therapy to be asymptomatic was 5.14 months (range, 2-11), with a mean of 16.14 months (range, 3-24), with the 7 patients currently maintained clean. CONCLUSIONS: The present study suggests that re-education of defecation maneuver through home training, seems to be an effective and efficient therapy, achieving excellent results in medium term.


OBJETIVO: Los trastornos de la defecación representan el 3% de las consultas en pediatría. Nuestro objetivo fue demostrar la eficacia y eficiencia de la reeducación en la maniobra defecatoria mediante el entrenamiento domiciliario en los pacientes con encopresis y disinergia esfinteriana. MATERIAL Y METODOS: Estudio de los pacientes con encopresis tratados mediante entrenamiento domiciliario en nuestro centro entre 2014-2015. Se realizó manometría anorrectal y fue valorada la maniobra defecatoria mediante la expulsión o no de la sonda rectal con o sin balón. Se realizaron sesiones diarias de forma domiciliaria empleando una sonda de Foley (18-20 Fr.) con llenado progresivo del balón, máximo 20 cc. Se evaluó la respuesta al tratamiento en función de la presencia de manchado. RESULTADOS: Se incluyeron 7 pacientes (6 varones y 1 mujer) con edad media de 9.7 años (rango, 5-15); dos con antecedente de malformación anorrectal, una enfermedad de Hirschsprung, 1 teratoma sacrococcígeo y 3 encopresis funcionales. Tres pacientes presentaban manchado diario y 4 de forma frecuente. La media de presión basal del canal fue de 32,34 mmHg (rango, 11,74-50,75) con maniobra defecatoria negativa en 2 casos, deficiente en 3 y disinérgica en 2. La media de tiempo realizando el entrenamiento intestinal hasta lograr estar asintomáticos fue 5.14 meses (rango, 2-11), con un seguimiento medio de 16,14 meses (rango, 3-24), manteniéndose limpios actualmente los 7 pacientes. CONCLUSIONES: El presente estudio sugiere que la reeducación de la maniobra defecatoria mediante entrenamiento domiciliario parece ser una terapia eficaz y eficiente, logrando excelentes resultados a medio plazo.


Asunto(s)
Canal Anal/fisiología , Defecación/fisiología , Encopresis/terapia , Incontinencia Fecal/terapia , Adolescente , Biorretroalimentación Psicológica/métodos , Niño , Preescolar , Incontinencia Fecal/etiología , Femenino , Humanos , Masculino , Manometría/métodos , Factores de Tiempo , Resultado del Tratamiento
2.
Cir. pediátr ; 30(1): 28-32, ene. 2017. ilus, tab
Artículo en Español | IBECS | ID: ibc-163330

RESUMEN

Objetivo. Los trastornos de la defecación representan el 3% de las consultas en pediatría. Nuestro objetivo fue demostrar la eficacia y eficiencia de la reeducación en la maniobra defecatoria mediante el entrenamiento domiciliario en los pacientes con encopresis y disinergia esfinteriana. Material y métodos. Estudio de los pacientes con encopresis tratados mediante entrenamiento domiciliario en nuestro centro entre 2014-2015. Se realizó manometría anorrectal y fue valorada la maniobra defecatoria mediante la expulsión o no de la sonda rectal con o sin balón. Se realizaron sesiones diarias de forma domiciliaria empleando una sonda de Foley (18-20 Fr.) con llenado progresivo del balón, máximo 20 cc. Se evaluó la respuesta al tratamiento en función de la presencia de manchado. Resultados. Se incluyeron 7 pacientes (6 varones y 1 mujer) con edad media de 9.7 años (rango, 5-15); dos con antecedente de malformación anorrectal, una enfermedad de Hirschsprung, 1 teratoma sacrococcígeo y 3 encopresis funcionales. Tres pacientes presentaban manchado diario y 4 de forma frecuente. La media de presión basal del canal fue de 32,34 mmHg (rango, 11,74-50,75) con maniobra defecatoria negativa en 2 casos, deficiente en 3 y disinérgica en 2. La media de tiempo realizando el entrenamiento intestinal hasta lograr estar asintomáticos fue 5.14 meses (rango, 2-11), con un seguimiento medio de 16,14 meses (rango, 3-24), manteniéndose limpios actualmente los 7 pacientes. Conclusiones. El presente estudio sugiere que la reeducación de la maniobra defecatoria mediante entrenamiento domiciliario parece ser una terapia eficaz y eficiente, logrando excelentes resultados a medio plazo (AU)


Objective. the defecation disorders represents the 3% of consultations in pediatrics patients. Our goal was to demonstrate the effectiveness and efficiency of the reeducation of the defecation maneuver through home training in patients with encopresis and sphincter dyssynergia. Material and methods. Study of patients with fecal incontinence treated with home training at our center between 2014-2015. Anorectal manometry was performed and was valued defecation maneuver by expulsion of rectal probe with or without the ball. Daily sessions were performed using a Foley catheter (18-20Fr.) with progressive filling of the balloon, maximum 20cc. The response to the treatment was assessed in terms of episodes of soiling. Results. Seven patients (6 males and 1 female) with a mean age of 9.7 years (range, 5-15) were included; two patients with anorectal malformation history, 1 Hirschsprung disease, 1 sacrococcygeal teratoma and 3 functional encopresis. Three patients had soiling episodes daily and 4 patients frequently. The mean basal pressure of anal channel was 32.34mmHg (range, 11.74-50.75) with negative defecation maneuver in 2 cases, deficient in 3 and dyssynergic in 2 patients. The mean time of biofeedback therapy to be asymptomatic was 5.14 months (range, 2-11), with a mean of 16.14 months (range, 3-24), with the 7 patients currently maintained clean. Conclusions. The present study suggests that re-education of defecation maneuver through home training, seems to be an effective and efficient therapy, achieving excellent results in medium term (AU)


Asunto(s)
Humanos , Niño , Masculino , Femenino , Encopresis/rehabilitación , Control de Esfínteres , Trastornos de Eliminación/rehabilitación , Incontinencia Fecal/rehabilitación , Manometría/métodos , Resultado del Tratamiento , Estudios Retrospectivos
3.
J Dent Res ; 91(4): 413-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22337699

RESUMEN

Mechanical stimulation contributes to the health of alveolar bone, but no therapy using the osteogenic effects of these stimuli to increase alveolar bone formation has been developed. We propose that the application of high-frequency acceleration to teeth in the absence of significant loading is osteogenic. Sprague-Dawley rats were divided among control, sham, and experimental groups. The experimental group underwent localized accelerations at different frequencies for 5 min/day on the occlusal surface of the maxillary right first molar at a very low magnitude of loading (4 µÎµ). Sham rats received a similar load in the absence of acceleration or frequency. The alveolar bone of the maxilla was evaluated by microcomputed tomography (µCT), histology, fluorescence microscopy, scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR imaging), and RT-PCR for osteogenic genes. Results demonstrate that application of high-frequency acceleration significantly increased alveolar bone formation. These effects were not restricted to the area of application, and loading could be replaced by frequency and acceleration. These studies propose a simple mechanical therapy that may play a significant role in alveolar bone formation and maintenance.


Asunto(s)
Proceso Alveolar/fisiología , Osteogénesis/fisiología , Vibración/uso terapéutico , Aceleración , Animales , Fenómenos Biomecánicos , Densidad Ósea/fisiología , Calcificación Fisiológica/fisiología , Carbonatos/análisis , Colágeno/ultraestructura , Imagenología Tridimensional/métodos , Masculino , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Diente Molar/fisiología , Tercer Molar/fisiología , Oscilometría , Estimulación Física , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Espectroscopía Infrarroja por Transformada de Fourier , Estrés Mecánico , Microtomografía por Rayos X/métodos
4.
Adv Exp Med Biol ; 648: 395-401, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19536504

RESUMEN

Selective inhibition of the Na(+)/H(+) exchanger type 3 (NHE3) increases the firing rate of brainstem ventrolateral CO(2)/H(+) sensitive neurons, resembling the responses evoked by hypercapnic stimuli. In anesthetized animals, NHE3 inhibition has also been shown to stimulate the central chemosensitive drive. We aimed to analyze the respiratory-related brainstem regions affected by NHE3 inhibition in anaesthetized spontaneously-breathing rats with intact peripheral afferents. For that, c-Fos immunopositive cells were counted along the brainstem in rats intravenously infused with the selective NHE3 inhibitor AVE1599. A rostral extension of the ventral respiratory column which includes the pre-Bötzinger complex was activated by the NHE3 inhibitor. In addition, the number of c-Fos positive cells resulted significantly increased in the most rostral extension of the retrotrapezoid nucleus/parapyramidal region. In the pons, the intravenous infusion of AVE1599 activated the lateral parabrachial and Kölliker-Fuse nuclei. Thus, selective NHE3 inhibition in anaesthetized rats activates the respiratory network and evokes a pattern of c-Fos expressing cells similar to that induced by hypercapnia.


Asunto(s)
Tronco Encefálico/efectos de los fármacos , Tronco Encefálico/fisiología , Respiración , Intercambiadores de Sodio-Hidrógeno/antagonistas & inhibidores , Animales , Tronco Encefálico/citología , Células Quimiorreceptoras/efectos de los fármacos , Células Quimiorreceptoras/metabolismo , Relación Dosis-Respuesta a Droga , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Wistar , Intercambiador 3 de Sodio-Hidrógeno
5.
Biol Trace Elem Res ; 109(1): 91-6, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16388106

RESUMEN

In this research, we measure the iron bioavailability of micronized ferric orthophosphate when it is used to fortify low-fat fluid milk enriched with calcium and petit suisse cheese using the prophylactic-preventive method in rats. Four groups of male weaned rats received a basal diet (control diet; 6.5 ppm Fe), a reference standard diet (SO4Fe; 18.2 ppm Fe), a basal diet using iron-fortified fluid milk as the iron source (milk diet; Fe ppm 17.9), and a basal diet using iron-fortified petit suisse cheese as the iron source (cheese diet; 18.0 ppm Fe) for 22 d. The iron bioavailability of the different sources was calculated as the ratio between the mass of iron incorporated into hemoglobin during the experiment and the total iron intake per animal. The relative biological values with regard to the reference standard (RBV%) were 61% and 69% for the milk and cheese diet, respectively. These results show that according to this method, the iron bioavailability in both fortified foods can be considered as medium bioavailability rates.


Asunto(s)
Queso , Alimentos Fortificados , Hierro/farmacocinética , Leche/química , Animales , Disponibilidad Biológica , Calcio/metabolismo , Dieta , Masculino , Ratas , Ratas Sprague-Dawley
6.
Biol Trace Elem Res ; 105(1-3): 187-95, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16034163

RESUMEN

Food fortification has been shown to be an effective strategy to overcome iron malnutrition. When a new iron compound is developed for this purpose, it must be evaluated from a nutritional and technological point of view before adding it into foods. In this way, we have evaluated ferrous gluconate stabilized by glycine as a new iron source to be used in wheat flour fortification. We performed biological studies in rats as well as sensory perceptions by human subjects in wheat flour fortified with this iron source. The productions of pentane as a rancidity indicator as well as the change of the sensorial properties of the biscuits made with stabilized ferrous gluconate-fortified wheat flour were negligible. Iron absorption in water from this iron source was similar to the reference standard ferrous sulfate. Nevertheless, because of the phytic acid content, iron absorption from fortified wheat flour decrease 40% for both iron sources. The addition of zinc from different sources did not modify iron absorption from ferrous sulfate and stabilized ferrous gluconate in water and wheat flour. The iron absorption mechanism as well as the biodistribution studies demonstrate that the biological behavior of this iron source does not differ significantly from the reference standard. These results demonstrate that the iron source under study has adequate properties to be used in wheat flour fortification. Nevertheless, more research is needed before considering this iron source for its massive use in food fortification.


Asunto(s)
Compuestos Férricos/farmacología , Alimentos Fortificados , Radioisótopos de Hierro/metabolismo , Triticum/metabolismo , Animales , Disponibilidad Biológica , Cromatografía , Femenino , Compuestos Férricos/química , Harina , Gluconatos/química , Glicina/química , Hierro/metabolismo , Hierro de la Dieta , Masculino , Pentanos/química , Percepción , Ácido Fítico/química , Ratas , Ratas Wistar , Estándares de Referencia , Gusto , Factores de Tiempo , Sulfato de Zinc/química
7.
Biol Trace Elem Res ; 104(3): 261-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15930595

RESUMEN

The aim of the study was to determine the relative bioavailability of zinc gluconate stabilized with glycine in a Petit Suisse cheese from an infant dessert. Weight gain and bone zinc content were the nutritional responses evaluated for the diets of different zinc content: 2 ppm (basal) and 5, 10, and 30 ppm from zinc gluconate stabilized with glycine and zinc sulfate. Nonlinear regression analysis of the fitted curves for weight gain determined a relative zinc bioavailability of 100% for the Ymax ratio and 96% for Ymax/t1/2 ratio for zinc gluconate stabilized with glycine (R2=0.7996 for zinc sulfate and 0.8665 for zinc gluconate stabilized with glycine). The slope ratio analysis from linear regression of femur zinc determined a relative zinc bioavailability of 93% for zinc gluconate stabilized with glycine (R2=0.8693 for zinc sulfate and 0.8307 for zinc gluconate stabilized with glycine). Zinc gluconate stabilized with glycine has similar bioavailability as zinc sulfate in a Petit Suisse cheese nutritional matrix, with the advantage that the stabilized compound does not modify the sensorial characteristics of the fortified cheese.


Asunto(s)
Biomarcadores , Queso/análisis , Aumento de Peso/efectos de los fármacos , Zinc/farmacocinética , Animales , Disponibilidad Biológica , Fémur/anatomía & histología , Fémur/química , Gluconatos/administración & dosificación , Glicina/administración & dosificación , Masculino , Ratas , Ratas Sprague-Dawley , Zinc/administración & dosificación , Sulfato de Zinc/administración & dosificación
8.
Biol Trace Elem Res ; 104(3): 269-73, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15930596

RESUMEN

Fortification of a Petit Suisse cheese with zinc sulfate and zinc gluconate stabilized with glycine was used as a tool to overcome zinc-deficiency effects on total-body growth and skeletal growth. Animals were divided in 4 groups of 10 rats: basal (B), control (C), depletion-repletion 1 (DR1), and depletion-repletion 2 (DR2). These four groups were fed with four diets: basal (2 ppm Zn), control (30 ppm Zn), DR1, and DR2; they received a basal diet for 14 d and a control diet for the other 14 d of the experiment, using zinc sulfate for DR1 and zinc gluconate stabilized with glycine for DR2. After 28 d of the experiment, total-body weight and weight gain of the control and DR1 and DR2 animals were not statistically different (p<0.05), Femur weight and femur zinc content of DR1 and DR2 did not achieve the values of control animals (p<0.05), but they were higher than that of basal animals. Our results show that restoration of dietary zinc levels by means of food fortification normalized weight gain, as an indicator of total-body growth, and presented a trend to normalize bone weight, as a marker of skeletal growth, in young rats and independently of the zinc source used.


Asunto(s)
Queso , Enfermedades Carenciales/dietoterapia , Alimentos Fortificados , Sulfato de Zinc/uso terapéutico , Zinc/deficiencia , Animales , Fémur/anatomía & histología , Fémur/química , Gluconatos/uso terapéutico , Glicina/uso terapéutico , Hematócrito , Hemoglobinas/análisis , Masculino , Ratas , Ratas Sprague-Dawley , Aumento de Peso/efectos de los fármacos , Zinc/uso terapéutico
9.
Biol Trace Elem Res ; 104(2): 173-83, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15894817

RESUMEN

Zinc and iron are crucial mineral components of human diet, because their deficiency leads to several disorders, including alterations of the immune function. It has been demonstrated, in both humans and rodents, that a diminished number of lymphoid cells and a loss of lymphocyte activity accompany deprivation of these essential minerals. The aim of this work was to analyze if iron and/or zinc imbalances regulate lymphocyte activity and the intracellular signals involved in the effect. Mice from the BALB/c strain were fed with iron- and/or zinc-deficient or mineral-supplemented diets, according to the American Institute of Nutrition Rodent Diets. Levels of iron and zinc were assessed in blood, liver, or bone samples. Selective mitogen stimulation of T- and B-lymphocytes were performed. We found a diminished proliferative response in T- and B-lymphocytes from zinc- and/or iron-deficient animals with respect to controls. These effects were related to decreased mitogen-induced translocation of protein kinase C (PKC) activity to cell membranes on both cell types from all animals fed with deficient diets. Our results demonstrate that iron and zinc deficiencies affect both T- and B-lymphocyte function by PKC-dependent mechanisms.


Asunto(s)
Linfocitos B/inmunología , Deficiencias de Hierro , Proteína Quinasa C/fisiología , Linfocitos T/inmunología , Zinc/deficiencia , Animales , Proliferación Celular/efectos de los fármacos , Concanavalina A/farmacología , Femenino , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos BALB C , Fitohemaglutininas/farmacología , Mitógenos de Phytolacca americana/farmacología
10.
Aliment Pharmacol Ther ; 20(10): 1029-34, 2004 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-15569104

RESUMEN

Helicobacter pylori causes a chronic gastric infection, which is usually life-long. Many epidemiological studies have shown that this is probably one of the most common bacterial infections throughout the world involving 30% of the population living in developed countries and up to 80-90% of the population in developing regions. Concomitantly, developing regions also have high prevalence of micronutrient malnutrition. In the last few years, some studies have suggested that H. pylori infection may affect the homeostasis of different micronutrients including iron, vitamin B12, folic acid, alpha-tocopherol, vitamin C and beta-carotene. In this article, we discuss the current scientific information of the effect that H. pylori infection may produce on micronutrient malnutrition.


Asunto(s)
Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Desnutrición/etiología , Micronutrientes/deficiencia , Humanos
11.
Rev Neurol ; 39(6): 555-64, 2004.
Artículo en Español | MEDLINE | ID: mdl-15467995

RESUMEN

INTRODUCTION: Carbon dioxide partial pressure and pH in the extracellular compartment are the most powerful signals regulating respiration. Central chemoreceptors (QC) undergo the stimulating effect of CO2 and pH upon respiration. AIMS: This review tries to provide an actual envision of the progress in the knowledgement on central chemoreception. It also tries to highlight the importance of the alterations in the chemoreception mechanism as a cause of sudden infant death syndrome (SIDS). DEVELOPMENT: Central chemoreceptors respond to acid-base imbalance acting on neurons that give rise to the central breathing pattern and have the ability to change the respiratory rate, which is normally needed to restore the normal values of acid-base status. QC are widely distributed in the brain stem, however QC neurons in the ventral surface of the medulla like to be the main relays for ventilatory responses after acid-base stimulation. CONCLUSIONS: It has been shown that QC are sensitive to pH and CO2 as in vivo as in vitro conditions, most of them being serotonin immunopositive, a neurotransmitter with known effects on breathing pattern. By other side, alterations of central chemoreception have been associated to pathologies like congenital hypoventilatory syndrome or SIDS. Interestingly, the post mortem exams of the brain of infants dead because these syndromes have showed anomalies of serotonergic receptor located in regions containing QC neurons and in others related with cardiorespiratory integration.


Asunto(s)
Células Quimiorreceptoras/metabolismo , Fenómenos Fisiológicos Respiratorios , Muerte Súbita del Lactante , Dióxido de Carbono/sangre , Humanos , Concentración de Iones de Hidrógeno , Lactante , Bulbo Raquídeo/citología , Bulbo Raquídeo/metabolismo , Neuronas/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Muerte Súbita del Lactante/etiología
12.
Arch. latinoam. nutr ; 53(2): 119-132, jun. 2003.
Artículo en Español | LILACS | ID: lil-356578

RESUMEN

Iron is an essential micronutrient involved in multiple biochemical and physiological process. In this review we discuss the most relevant aspect of its metabolism in order to reach a better comprehension of the relevant roll that this micronutrient plays in human health.


Asunto(s)
Humanos , Hierro/metabolismo , Micronutrientes/metabolismo , Absorción , Hierro/farmacocinética , Micronutrientes/farmacocinética
13.
J Physiol ; 549(Pt 1): 181-94, 2003 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-12665611

RESUMEN

The ventral surface of the caudal ventrolateral medulla (cVLM) has been shown to generate intense respiratory responses after surface acid-base stimulation. With respect to their chemosensitive characteristics, cVLM neurons have been less studied than other rostral-most regions of the brainstem. The purpose of these experiments was to determine the bioelectric responses of cVLM neurons to acidic stimuli and to determine their chemosensitive properties. Using extracellular and microiontophoretic techniques, we recorded electrical activities from 117 neurons in an area close to the ventral surface of the cVLM in anaesthetised rats. All neurons were tested for their sensitivity to H+. The fluorescent probe BCECF was used to measure extracellular pH changes produced by the microiontophoretic injection of H+ in brainstem slices. This procedure provided an estimation of the local changes in pH produced by microiontophoretic H+ application in the anaesthetised rat. Neurons coupled to the respiratory cycle, R (n = 51), were not responsive to direct stimulation with H+. Sixty-six neurons that did respond to H+ stimulation were uncoupled from respiration, and identified as NR neurons. These neurons presented distinct ranges of H+ sensitivity. The neuronal sensitivity to H+ was mainly assessed by the slope of the stimulus-response curve, where the steeper the slope, the higher the H+ sensitivity. On this basis, NR neurons were classed as being either weakly or highly sensitive to H+. NR neurons with a high H+ sensitivity (n = 12) showed an average value of 34.17 +/- 7.44 spikes s-1 (100 nC)-1 (mean +/- S.D.) for maximal slope and an EC50 of 126.76 +/- 33 nC. Suprathreshold H+ stimulation of highly sensitive NR neurons elicited bursting pattern responses coupled to the respiratory cycle. The bursting responses, which were synchronised with the inspiratory phase and the early expiratory phase of the respiratory cycle, lasted for several seconds before returning to the steady state firing pattern characteristic of the pre-stimulus condition. These NR neurons, which possess the capacity to detect distinct H+ concentrations in the extracellular microenvironment, are excellent candidates to serve in a chemoreceptor capacity in the caudal medulla.


Asunto(s)
Equilibrio Ácido-Base/fisiología , Bulbo Raquídeo/fisiología , Neuronas/fisiología , Protones , Potenciales de Acción/fisiología , Animales , Células Quimiorreceptoras/fisiología , Femenino , Iontoforesis , Masculino , Bulbo Raquídeo/citología , Ratas , Ratas Wistar , Respiración , Estimulación Química
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(6 Pt 2): 066604, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12188848

RESUMEN

We show that a laser beam which propagates through a cubic-quintic nonlinear optical material may reach, for a given power, a condensed state with a collisional dynamics resembling a liquid drop. We qualitatively describe the analogies between this system and the usual fluids and show them by simulating numerically total reflections of these beams with planar boundaries and localized defects. We use the analogy "liquid light" to stress the connections with the dynamics of quantum fluids, including Bose-Einstein condensates.

15.
Phytother Res ; 15(2): 162-4, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11268119

RESUMEN

Several species of the genus Passiflora, known in Brazil as "maracujá", have widespread use in folk medicine as sedatives and tranquillizers. The anxiolytic activity of hydroethanol extracts of P. alata and P. edulis leaves was evaluated using the elevated plus-maze test. The extracts presented anxiolytic activity in dosages around 50, 100 and 150 mg/kg.


Asunto(s)
Ansiolíticos/farmacología , Aprendizaje por Laberinto/efectos de los fármacos , Plantas Medicinales , Rosales , Animales , Relación Dosis-Respuesta a Droga , Masculino , Extractos Vegetales/farmacología , Hojas de la Planta , Ratas , Ratas Wistar
16.
Biol Trace Elem Res ; 84(1-3): 123-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11817683

RESUMEN

The bioavailability of iron from a new commercial source containing ferric gluconate stabilized with glycine sold under the trade name Bioferrico was studied in this work by means of the prophylactic-preventive test in rats. NaFeEDTA was also studied by the same methodology for comparative purposes and ferrous sulfate was used as the reference standard. The test was conducted for 4 wk with male weaned rats, which were randomized into four groups of at least eight animals each. A control group received a basal diet of low-iron content, whereas the other groups received the same diet with iron added at a dose of 20 mg/kg as FeSO4.7H2O, NaFeEDTA, and Bioferrico, respectively. Individual hemoglobin concentrations (HbC) and weights were determined at the beginning and at the end of the study and food intake was daily registered. The iron bioavailability (BioFe) of each source was calculated as the ratio between the amount of iron incorporated into hemoglobin during the treatment (HbFe) and the total iron intake per animal (ToFeIn). A relative biological value (RBV) was obtained for each iron source under study as the ratio between the BioFe of the tested compound and that of the reference standard. The RBVs were 98% and 86% for Bioferrico and NaFeEDTA, respectively. Bioferrico showed a high bioavailability and behaved inertly in relation to the sensorial properties of the fortified food when it was added to flour. These qualities emphasize Bioferrico as a promising source for iron fortification.


Asunto(s)
Compuestos Férricos/farmacología , Gluconatos/farmacología , Hierro/farmacocinética , Animales , Peso Corporal , Ácido Edético/farmacología , Glicina/farmacología , Hemoglobinas/biosíntesis , Deficiencias de Hierro , Masculino , Ratas
17.
J Ethnopharmacol ; 73(1-2): 261-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11025164

RESUMEN

The alcoholic extract of Pfaffia glomerata roots (100, 500, 1000 mg/kg, intraperitoneally (i.p.), and 500, 1000, 1500 mg/kg, per os) was studied in several behavioral animal models for the evaluation of central activity: open field, barbiturate sleeping time, pentilenotetrazole (PTZ)-induced convulsions, elevated plus-maze, step-down inhibitory avoidance and forced swimming test. The acute treatment (500 mg/kg, i.p.) interfered with the open-field habituation, decreased sleep latency and increased barbiturate-induced sleeping time, protected partially the animals of PTZ-induced convulsions, decreased the memory retention in step-down inhibitory avoidance, and did not have an important effect in the elevated plus-maze test and forced swimming test. The same extract at 1000 mg/kg per os did not cause any effect in barbiturate sleeping time and pentilenotetrazole-induced convulsions models. Thus, the effect on the memory was deeper evaluated in the step-down inhibitory avoidance task. When administered by intraperitoneal route, the extract showed a dose-dependent effect causing full amnesia at 1000 mg/kg. On the other hand, when it was given by oral route at 500, 1000 and 1500 mg/kg, no influence on the memory retention was observed. These results suggest that the alcoholic extract of P. glomerata roots presents different effects depending on the route of administration: by i.p route, it seems to be a central nervous system depressant agent; by oral route, it seems to be ineffective, at least in the tested doses.


Asunto(s)
Conducta Animal/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas , Administración Oral , Análisis de Varianza , Animales , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Inyecciones Intraperitoneales , Masculino , Memoria/efectos de los fármacos , Ratones , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Psicofarmacología , Ratas , Ratas Wistar , Convulsiones/inducido químicamente , Convulsiones/tratamiento farmacológico
18.
Behav Pharmacol ; 11(2): 169-73, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10877122

RESUMEN

This report describes the effects of the antiepileptic agent gabapentin on anxiety and memory. Male Wistar rats received intraperitoneal administrations of gabapentin (10, 30 and 100mg/kg), diazepam (1 mg/kg), saline or diazepam vehicle 30 minutes prior to experimental procedures. Animals were: (1) tested on step-down inhibitory avoidance (footshock 0.3 mA) and habituation to an open-field for memory assessment; and (2) submitted to the elevated plus-maze to evaluate the potential anxiolytic effects of gabapentin. Animals treated with gabapentin showed a reduction in anxiety similar to that observed in animals treated with diazepam. Memory was not affected by gabapentin in any of the tests, but was impaired by diazepam. The lack of effects of gabapentin on memory suggest a potential advantage of this drug over compounds with previously known anxiolytic property, which have amnesic effects at doses used for the treatment of anxiety disorders.


Asunto(s)
Acetatos/farmacología , Aminas , Amnesia/inducido químicamente , Ansiolíticos/farmacología , Anticonvulsivantes/farmacología , Ácidos Ciclohexanocarboxílicos , Ácido gamma-Aminobutírico , Amnesia/psicología , Animales , Reacción de Prevención/efectos de los fármacos , Gabapentina , Masculino , Memoria/efectos de los fármacos , Ratas , Ratas Wistar
19.
Artículo en Español | MEDLINE | ID: mdl-10797835

RESUMEN

It is now well known that zinc is an essential micronutrient. Even though much information is available, there are many points that remain to be studied. zinc is absorbed by the intestine and transported in the plasma by albumin, forming a small exchangeable pool, which is rapidly exhausted even in cases of mild deficiency. zinc is essential for the activity of about 70 enzymes among other functions. Therefore, zinc deficiency produces a great number of clinical disorders, the symptoms of which may range between mild up to serious dysfunctions. These problems are corrected by a dietary supplementation with zinc. The lack of a reliable method to determine the zinc nutritional status reflects the problem to estimate the metal recommended dietary allowances, which are difficulty met specially by children, old persons and pregnant women which constitute the main risk groups. Although our knowledge concerning zinc toxicity is scarce, it is well known that the amounts of zinc that produces toxic effects are much higher than those that are contained in regular diets as well as in diets supplemented with this metal. Therefore, the need of the development of effective strategies, like food fortification with proper zinc compounds, appears as an attractive alternative in order to prevent and/or correct the deficiency of this vital element and to improve the health and the life quality of the whole population.


Asunto(s)
Zinc/fisiología , Factores de Edad , Animales , Femenino , Humanos , Absorción Intestinal/fisiología , Masculino , Ratones , Necesidades Nutricionales , Valor Nutritivo , Embarazo , Ratas
20.
Appl Opt ; 38(14): 3039-45, 1999 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-18319889

RESUMEN

A novel, to our knowledge, integrated wavelength-division multiplexing-passive optical net demultiplexer that uses an arrayed-waveguide grating and diffractive optical elements is presented. The demultiplexer is used to distribute 1.3-microm wavelength signals and to multiplex an eight-channel wavelength-division multiplexer spectrum at a 1.55-microm wavelength. The device shows high functionality and good optical performance. The measured cross talk was less than -21 dB, and the 3-dB bandwidth was determined to be 97 GHz, which is close to the theoretical value of 93 GHz. Average losses of 4.5 and 8 dB were measured for the 1.3- and the 1.55-microm signals, respectively.

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