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1.
Cir. pediátr ; 26(4): 167-172, oct. 2013. ilus
Artículo en Español | IBECS | ID: ibc-118367

RESUMEN

Objetivos. Numerosas patologías que afectan a la vejiga, de origen congénito (extrofia) o adquirido (traumatismos, tumores), requieren la reconstrucción de la pared vesical utilizando intestino delgado, sigma o estómago, los cuales no están exentos de complicaciones. Por ese motivo, en el presente trabajo pretendemos desarrollar un nuevo modelo de pared vesical humana mediante ingeniería tisular que pudiese tener una utilidad clínica. Material y métodos. En primer lugar, se procedió a generar cultivos primarios de células epiteliales y estromales de la mucosa vesical a partir de pequeñas biopsias de la pared vesical humana, utilizando para ello técnicas de digestión enzimática mediante tripsina-EDTA y colagenasa. Posteriormente, se generó un sustituto tridimensional de la mucosa vesical utilizando como soporte biomateriales de fibrina-agarosa. El análisis de las muestras se realizó a los 14 días mediante examen histológico de muestras teñidas con hematoxilina-eosina. Resultados. La aplicación de los métodos de digestión enzimática permitió generar eficientemente cultivos primarios de células epiteliales y estromales de la mucosa vesical humana, comprobándose que la tasa de proliferación de las células estromales era superior a la de las células epiteliales. Una vez generados los sustitutos de la pared vesical, se comprobó el adecuado nivel de biocompatibilidad del biomaterial y las células estromales y epiteliales. La estructura histológica de los sustitutos de pared vesical presentaba una gran analogía con la mucosa vesical humana nativa. Conclusiones. El tejido vesical generado por ingeniería tisular muestra importantes similitudes estructurales e histológicas con el tejido vesical nativo. Estos resultados sugieren que los tejidos generados mediante ingeniería tisular podrían tener utilidad terapéutica en el futuro (AU)


Introduction. Certain urological congenital conditions, such as bladder exstrophy and acquired conditions such as trauma and tumors may require the use of different tissues like small bowel, sigmoid colon or stomach for bladder reconstruction. However, these tissues are often associated to important complications. The aim of this study is to develop a novel substitute of the human bladder wall by tissue engineering. Material and methods. We first generated primary cell cultures of epithelial and stromal bladder mucosa cells from small tissue biopsies of human bladder by using enzymatic methods based on trypsin-EDTA and collagenase I. Then, a three-dimensional substitute of the bladder mucosa was generated using fibrin-agarose biomaterials. The analysis of the tissue substitutes was carried out at day 14th of development by histological examination of samples stained with hematoxylin-eosin. Results. The use of enzymatic digestion methods allowed us to efficiently generate primary cell cultures of the human bladder epithelial and stromal cells. The proliferation rate was higher in stromal cells as compared to epithelial cells. Once the bladder mucosa substitutes were generated, a good biocompatibility of the stromal and epithelial cells into the biomaterial was found. The histological structure of the bladder wall substitutes was analogue to that of the native human bladder mucosa. Conclusions. The bladder mucosa substitute generated by tissue engineering showed structural and histological similarities with the native human bladder tissues and open the door to the future therapeutic use of these bioengineered tissues (AU)


Asunto(s)
Humanos , Vejiga Urinaria/cirugía , Ingeniería Celular/métodos , Materiales Biocompatibles/uso terapéutico , Procedimientos de Cirugía Plástica/métodos , Supervivencia Tisular
2.
Cir Pediatr ; 26(4): 167-72, 2013 Oct.
Artículo en Español | MEDLINE | ID: mdl-24645241

RESUMEN

INTRODUCTION: Certain urological congenital conditions, such as bladder exstrophy and acquired conditions such as trauma and tumors may require the use of different tissues like small bowel, sigmoid colon or stomach for bladder reconstruction. However, these tissues are often associated to important complications. The aim of this study is to develop a novel substitute of the human bladder wall by tissue engineering. MATERIAL AND METHODS: We first generated primary cell cultures of epithelial and stromal bladder mucosa cells from small tissue biopsies of human bladder by using enzymatic methods based on trypsin-EDTA and collagenase I. Then, a three-dimensional substitute of the bladder mucosa was generated using fibrin-agarose biomaterials. The analysis of the tissue substitutes was carried out at day 14th of development by histological examination of samples stained with hematoxylin-eosin. RESULTS: The use of enzymatic digestion methods allowed us to efficiently generate primary cell cultures of the human bladder epithelial and stromal cells. The proliferation rate was higher in stromal cells as compared to epithelial cells. Once the bladder mucosa substitutes were generated, a good biocompatibility of the stromal and epithelial cells into the biomaterial was found. The histological structure of the bladder wall substitutes was analogue to that of the native human bladder mucosa. CONCLUSIONS: The bladder mucosa substitute generated by tissue engineering showed structural and histological similarities with the native human bladder tissues and open the door to the future therapeutic use of these bioengineered tissues.


Asunto(s)
Membrana Mucosa/citología , Ingeniería de Tejidos/métodos , Vejiga Urinaria/citología , Eosina Amarillenta-(YS)/química , Hematoxilina/química , Humanos , Coloración y Etiquetado
3.
Cir. pediátr ; 24(1): 13-18, ene. 2011.
Artículo en Español | IBECS | ID: ibc-107287

RESUMEN

La reconstrucción de grandes defectos de mucosa oral a menudo es desafiante, por la escasez de mucosa oral sana para reemplazar tejidos dañados. De esta forma, las técnicas de ingeniería tisular pueden suponer una fuente de tejidos autólogos disponible para trasplantar a estos pacientes. En este trabajo hemos desarrollado un nuevo modelo de mucosa oral artificial generada mediante ingeniería tisular usando un soporte de fibrina-agarosa. Para ello, se han generado cultivos primarios de fibroblastos de la mucosa oral humana y queratinocitos a partir de pequeñas biopsias de mucosa oral normal y aplicándoles tratamiento senzimáticos. Después, se ha determinado la viabilidad de las células cultivadas mediante microanálisis por rayos-X, demostrando que la mayoría de las células de los cultivos primarios estaban vivas y tenían elevados K/Na ratios. Una vez que la viabilidad celular fue determinada, se usaron los fibroblastos y queratinocitos cultivados para desarrollar un constructo de mucosa oral sobre una matriz extracelular de (..) (AU)


Reconstruction of large oral mucosa defects is often challenging, since the shortage of healthy oral mucosa to replace the excised tissues. This way, tissue ingineering techniques may provide a source of autologoustissues available for transplant in these patients. In this work, wehave developed a new model for artificial oral mucosa generated by tissue engineering using a fibrin-agarosa scaffold. For that purpose, we have generated primary cultures of human oral mucosa fibroblasts and keratinocytes from small biopsies of normal mucosa oral using enzymatic treatments. Then, we have determined the viability of cultured cells by electron probe quantitative X-ray microanalysis, and we have demonstrated that most of the cells in the primary cultures were alive and hd high K/Na ratios. Once cell viability was determined, we used cultured fibroblasts and keratinocytes to develop an artificial oral mucosaconstruct by using a fibrin-agarosa extracellular matrix and a sequential culture technique using porous culture inserts. Histological analysis of the artificial tissues showed high similarities with normal oral (..) (AU)


Asunto(s)
Humanos , Mucosa Bucal/trasplante , Órganos Artificiales/provisión & distribución , Ingeniería Celular/métodos , Procedimientos de Cirugía Plástica/métodos , Fibrina/biosíntesis , Colágeno/biosíntesis , Fibroblastos/trasplante , Queratinocitos/trasplante
4.
Cir Pediatr ; 24(1): 13-8, 2011 Jan.
Artículo en Español | MEDLINE | ID: mdl-23155644

RESUMEN

Reconstruction of large oral mucosa defects is often challenging, since the shortage of healthy oral mucosa to replace the excised tissues. This way, tissue ingineering techniques may provide a source of autologous tissues available for transplant in these patients. In this work, we have developed a new model for artificial oral mucosa generated by tissue engineering using a fibrin-agarosa scaffold. For that purpose, we have generated primary cultures of human oral mucosa fibroblasts and keratinocytes from small biopsies of normal mucosa oral using enzymatic treatments. Then, we have determined the viability of cultured cells by electron probe quantitative X-ray microanalysis, and we have demonstrated that most of the cells in the primary cultures were alive and hd high K/Na ratios. Once cell viability was determined, we used cultured fibroblasts and keratinocytes to develop an artificial oral mucosa construct by using a fibrin-agarosa extracellular matrix and a sequential culture technique using porous culture inserts. Histological analysis of the artificial tissues showed high similarities with normal oral mucosa controls. The epithelium of the oral substitutes had several layers, with desmosomes and apical microvilli and microplicae. Both the controls and de oral mucosa substitutes showed high suprabasal expression of cytokeratin 13 and low expression of cytokeratin 10. All these results suggest that our model of oral mucosa using fibrin-agarose scaffolds show several similarities with native human oral mucosa.


Asunto(s)
Mucosa Bucal/cirugía , Ingeniería de Tejidos/métodos , Técnicas de Cultivo de Célula , Humanos , Procedimientos de Cirugía Plástica/métodos
5.
An. esp. pediatr. (Ed. impr) ; 55(6): 576-579, dic. 2001.
Artículo en Es | IBECS | ID: ibc-15673

RESUMEN

La ectopia ureteral se presenta con una baja prevalencia y por lo general se asocia con duplicidad pieloureteral. En estos casos es frecuente la aparición de incontinencia. Se presentan los casos clínicos de 5 pacientes tratadas en el Hospital Materno-Infantil Virgen de las Nieves por presentar incontinencia urinaria secundaria a ectopia ureteral asociada a duplicidad. En tres de ellas el uréter ectópico desembocaba en el útero y en las otras dos en la vagina. Se eligió la heminefroureterectomía por ser este segmento hipofuncionante o displásico. La incontinencia desapareció tras la intervención quirúrgica (AU)


Asunto(s)
Preescolar , Niño , Adolescente , Femenino , Humanos , Incontinencia Urinaria , Uréter , Procedimientos Quirúrgicos Urológicos
6.
Rev. esp. pediatr. (Ed. impr.) ; 56(5): 449-451, sept. 2000. ilus
Artículo en ES | IBECS | ID: ibc-3892

RESUMEN

La dilatación segmentaria del intestino delgado es una malformación poco frecuente que puede provocar episodios de oclusión o suboclusión intestinal.La etiología de esta entidad es desconocida, existiendo diversas teorías para explicar su origen. Presentamos los casos de dos pacientes varones de 1 y 2 años de edad que presentaban dilatación segmentaria de íleon, asociándose uno de ellos a un divertículo de Meckel. Se discute el posible origen vascular de esta enfermedad (AU)


Asunto(s)
Preescolar , Lactante , Masculino , Humanos , Íleon/anomalías , Enfermedades del Íleon/congénito , Obstrucción Intestinal/etiología , Dilatación Patológica , Enfermedades del Íleon/cirugía , Obstrucción Intestinal/cirugía
7.
Cir. pediátr ; 13(2): 64-68, abr. 2000.
Artículo en Es | IBECS | ID: ibc-7203

RESUMEN

Introducción. Diversos estudios han demostrado que, entre uno y dos tercios de los casos, la demanda urgente de atención es considerada inapropiada. Esta situación conlleva un aumento de los costes sanitarios y supone para el usuario una atención médica fragmentada. En el ámbito de la especialidad de Cirugía Pediátrica no hemos encontrado ningún trabajo realizado a tal efecto. Objetivos. 1. Cuantificar el grado de inadecuación de la demanda urgente en Cirugía Pediátrica. 2. Conocer los factores asociados a la demanda inadecuada. Pacientes y métodos. Diseño: estudio de observación transversal. Ambito: pacientes visitados por cirujano pediatra en Servicio de Urgencias Pediátrica* de un hospital universitario. Muestra: aleatoria (a: 0,05; precisión: 0,05) de los pacientes atendidos durante 1998. Variables de estudio: dependiente: inadecuación; independientes: edad, género, distancia desde el domicilio, diagnóstico, nivel de estudios de los padres, asistencia previa y si acude por iniciativa propia. Mediante entrevista: motivos que inducen a la demanda. Unidad de análisis: se consideró urgencia hospitalaria, siguiendo los criterios de la OMS, cuando se trata de emergencia vital o cuando existe necesidad de usar medios diagnósticos o terapéuticos no disponibles en un nivel de atención inferior. Análisis: el tratamiento estadístico consistió en un análisis de frecuencias relativas, prueba x2 para comparar frecuencias y 't' de Student para comparar medias. Resultados. De los 2.226 pacientes atendidos en urgencias, se han estudiado 441 (edad: 5,54 años; 63 por ciento varones). Los diagnósticos más frecuentes han sido: heridas y pequeños traumatismos (39,7 por ciento), dolor abdominal (22,2 por ciento), quemaduras (3,6 por ciento), apendicitis (3,2 por ciento) y hernias (3,2 por ciento). El 86,2 por ciento acudieron por iniciativa propia. La proximidad (19,9 por ciento), la alarma por los síntomas (13,1 °Io) y el desconocimiento de la existencia de otros niveles de atención (10 por ciento) han sido las causas argüidas por los padres para la demanda de atención. El 63,9 por ciento de las visitas se consideraron inapropiadas. Se ha encontrado relación estadística entre uso inapropiado y edad superior a un año (p < 0,02), distancia domicilio-hospital (p < 0,003), acudir por iniciativa propia (p < 0,001) y expectativa de los padres (p < 0,02). No existe relación con el género o el nivel de estudios de los padres. Conclusiones. En los Servicios de Urgencias existe un elevado número de consultas inadecuadas. La accesibilidad, la disponibilidad de medios, la rapidez de la atención .y quién toma la decisión de acudir son variables predictoras de la sobreutilización (AU)


Asunto(s)
Preescolar , Niño , Adolescente , Masculino , Lactante , Femenino , Humanos , Revisión de Utilización de Recursos , España , Procedimientos Quirúrgicos Operativos , Procedimientos Innecesarios , Estudios Transversales , Hospitales Universitarios , Servicios Médicos de Urgencia
8.
Cir Pediatr ; 13(2): 64-8, 2000 Apr.
Artículo en Español | MEDLINE | ID: mdl-12602005

RESUMEN

BACKGROUND: Several studies have demonstrated that, between 30-60% of the cases, the urgent attention demand is considered inappropriate. This situation causes an increase in the sanitary costs and supposes for the patient a partial medical care. In the area of the Pediatric Surgery we have not found any work accomplished to such effect. DESIGN: Transverse observational study. SETTING: Emergency Service of a University Hospital. PATIENTS: a sample random (alpha: 0.05; precision: 0.05) of the patients attended during 1998. MAIN OUTCOME MEASURES: Dependent: appropriateness. Independent: age, gender, proximity, diagnostic, studies of the parents, previous assistance, if attends by own initiative and motives that induce to demand. It was considered hospital emergency, continuing the criteria of the WHO, when it is considered vital emergency or when there is using of therapeutic or diagnostic means nor available in an primary level of health care. The statistic treatment consisted of a relative frequencies analysis, test x2 and t Student. RESULTS: Of 2,226 cases attended in emergency service, they have 441 reviewed (age: 5.54 years; 63% male). The most frequent diagnoses have been: injuries and small traumatisms (39.7%), abdominal pain (22.2%), burns (3.6%), appendicitis (3.2%) and hernias (3.2%); 86.2% attended by own initiative. The proximity (19.9%), the alarm by the symptoms (13.1%) and the ignorance of the existence of other level of health care (10%) have been the causes by the parents for attention demand. The 63.9% of the visits were considered inappropriate. It has been found relationship between inappropriate use and age (p < 0.02), proximity (p < 0.003), to attend by own initiative (p < 0.001), and expectation of the parents (p < 0.02). It does not exist relationship to the gender or the studies level of the parents. CONCLUSIONS: These data suggest that in the Emergency Services exists a high appropriateness. The accessibility, the availability of means, the rapidity of the attention and who takes the decision of attending are variable associated to the appropriateness.


Asunto(s)
Servicios Médicos de Urgencia/estadística & datos numéricos , Procedimientos Quirúrgicos Operativos/estadística & datos numéricos , Procedimientos Innecesarios/estadística & datos numéricos , Revisión de Utilización de Recursos , Adolescente , Niño , Preescolar , Estudios Transversales , Femenino , Hospitales Universitarios/estadística & datos numéricos , Humanos , Lactante , Masculino , España
9.
Cir Pediatr ; 12(1): 11-5, 1999 Jan.
Artículo en Español | MEDLINE | ID: mdl-10198543

RESUMEN

BACKGROUND: There is wide-spread consensus that a part of the use of hospital resources is inadequate in the sense that the patients receive services that do not provide them with any significant benefits, or that could be more beneficial, or less costly, with a lower care standard. OBJECTIVE: The main aim of this work is to determine the percentage of inadequate stays in a pediatric surgery service and to identify the causes that provoke them. METHOD: It was a concurrent study in pediatric patients entered, at least 24 hours, by different disease for surgery, observation or study. Revising trained applied the pediatric version of the Appropriateness Evaluation Protocol on the medical records of these patients. It has been measured if the stay was appropriated or not, and the cause. RESULTS: The studied patients (279) caused a total of 1,001 stays of those which 373 (37.3%) were deemed to be unnecessary. The diseases with greater number of inappropriate stays were cryptorchidia (97.3%), hernia (88.9%), hypertrophic pyloric stenosis (50%), and soft tissues surgery (43.1%). A 68.2% of the unnecessary stays were responsibility of the hospital-service-surgeon, a 22.6% to the associated environment-familiar, and a 9.2% to the lack of alternative resources to the hospital. CONCLUSIONS: A meaningful proportion by day of hospital stay would be avoided. The unnecessary stays search facilitates the weak points identification on those which to develop improvement actions.


Asunto(s)
Servicios de Salud del Niño/estadística & datos numéricos , Cirugía General , Mal Uso de los Servicios de Salud , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , España
10.
Cir Pediatr ; 11(2): 76-8, 1998 Apr.
Artículo en Español | MEDLINE | ID: mdl-9608147

RESUMEN

This paper studies the gonadal-hormonal and spermatic function of 48 adults (over 18 years old) who were treated in childhood for cryptorchidism by medical, surgical or both treatments. We measure plasmatic levels of FSH, LH, testosterone and prolactin of 34 patients and sperm samples of 31 patients. The testicular hormonal function was not disturbed except in four patients with high levels of prolactin (> 20 ng/ml) without symptoms. The spermatic function was disturbed in bilateral cryptorchidism mainly. The better sperm quality and testicular volume were at patients treated with hormonal treatment before surgical treatment.


Asunto(s)
Criptorquidismo/cirugía , Hormona Folículo Estimulante/sangre , Hormona Luteinizante/sangre , Prolactina/sangre , Espermatozoides , Testosterona/sangre , Adulto , Niño , Humanos , Masculino
11.
Cir Pediatr ; 8(3): 102-4, 1995 Jul.
Artículo en Español | MEDLINE | ID: mdl-8527312

RESUMEN

It's perform a descriptive study about a series of events with the purpose of discover the own characteristics of ovarian cysts and which characteristics determine its treatment. In the 41 patients (10 newborn, 14 prepubertal females and 17 post-menarchal females) we analyzed their symptoms, pathological findings, ecographics details, treatment, diagnostic and follow-up. The predominant symptom has been the abdominal pain (18 patients). In 8 newborn the cyst was find before born by prenatal sonography. The cyst was palped like abdominal mass in 22 patients and it was like a picture of acute abdomen in 11. It was found in the right ovary in 24 patients and bilaterally in 7. By pelvic ultrasonography was observed a superior size of 5 cm of diameter in 28 occasions, in 17 there were imagine of complex and in 3 there were hemorrhagic. In 16 patients the suspicion diagnostic was of torsion and in 5 of appendicitis. The torsion was confirmed in 11. In 16 patients it was a follicular cyst, in 9 was a dermoidal and in 9 hemorrhagic. Was realized a surgical treatment (cystectomy or ooforectomy in 36 girls, in 4 was realized a puncture and evacuation (bigger of 5 cm with clear liquid) and in 7 was hope the spontaneous evolution (clear liquid and infer size of 5 cm). There were not relapses. The clinic manifestations are presents with own characteristics depending of the cyst affected to newborn, premenarchal or menarchal females. The indications of surgery are: symptoms which are not resolved after a observation time (24-49 hours) and cysts of big volume associated a complications.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Quistes Ováricos/cirugía , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Quistes Ováricos/diagnóstico , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonografía
12.
Cir Pediatr ; 7(3): 140-2, 1994 Jul.
Artículo en Español | MEDLINE | ID: mdl-7999519

RESUMEN

With the aim of describe a typology that will result in a more precise diagnostic which in turn will permit the selection of the most direct method approach, an analysis was made of the clinical characteristics of patients we treated due to the presence of torsion of the testicular and epididymal appendages. A retrospective review was made of 91 patients, taking into account this age, time of appearance, time of evolution, symptoms, physical examination, histological study and effects. The average age was 9.47 years with a greater incidence occurring between the eight and twelve years old. No influence due to a seasonal phase was detected. The time span between the initial appearance of the symptoms and the time of admittance was 39.5 hours, being somewhat less in patients below the age of six. The common symptom was pain. In addition, 58.2% of the patients also suffered scrotal affectation. In 31 patients the hydatid was palpable and in 19 the "blue dot sign" rendered positive. In 83 cases, surgery was done via the scrotum, resulting in the confirmation of the initial diagnosis. The affectation of the left side was more frequent (62.5%). The hospital discharge was possible in less than 48 hours with no visible long-term effects. Thus, we believe that it is possible to almost always make a diagnosis based on the clinical data, and the type of treatment to be applied should be the extirpation of the hydatid to be carried out via the scrotum.


Asunto(s)
Torsión del Cordón Espermático/diagnóstico , Adolescente , Distribución por Edad , Estudios de Casos y Controles , Niño , Preescolar , Epidídimo , Humanos , Incidencia , Masculino , Estudios Retrospectivos , España/epidemiología , Torsión del Cordón Espermático/clasificación , Torsión del Cordón Espermático/epidemiología , Torsión del Cordón Espermático/cirugía
13.
Cir Pediatr ; 4(1): 23-5, 1991 Jan.
Artículo en Español | MEDLINE | ID: mdl-2043430

RESUMEN

Eighty patients to operated upon secondary hidronephrosis to pieloureteral or ureterovesical stenosis are studied. Diary diuresis and excretion of sodium of the operated kidney and the healthy kidney are valorated. We analyse the differences between age groups, grade of parenquima afectation or kind of pathology that cause the obstruction. Results show that the desobstruction of the urinary tract is accompanied by a increase of diuresis (p less than 0.001) and by a lost of sodium (p less than 0.001) in the operated kidney. Poliury is bigger in neonatal period than in other age groups.


Asunto(s)
Hidronefrosis/etiología , Poliuria/fisiopatología , Complicaciones Posoperatorias/fisiopatología , Obstrucción Ureteral/cirugía , Preescolar , Femenino , Humanos , Masculino , Síndrome , Obstrucción Ureteral/complicaciones
14.
Cir Pediatr ; 3(2): 45-8, 1990 Apr.
Artículo en Español | MEDLINE | ID: mdl-2252847

RESUMEN

22 patients, divided in 2 groups, are studied under-going intestinal resection as consequence of different pathological entities. Group I of 13 patients who had the ileocecal unión resected. Group II is made up of 9 patients who had small fragments of the small intestine enucleated. All the patients have, among other things, various anthropometrical, hematological and biochemical parameters, and their Ca/P metabolism analyzed, as well as the elimination of urinary nitrogen in its different forms. The patients who underwent resection of the ileocecal union present anthropometrical alterations, which can be consequence of a state of chronic malnutrition. The differences found in the alkaline phosphatase and in the elimination of amino acids in the urine can be a sign of a bacterial contamination of the small intestine by fecal flora or a sign of less availability of energetic contribution.


Asunto(s)
Trastornos del Crecimiento/etiología , Válvula Ileocecal/cirugía , Trastornos Nutricionales/etiología , Complicaciones Posoperatorias , Fosfatasa Alcalina/sangre , Aminoácidos/orina , Calcio/metabolismo , Niño , Trastornos del Crecimiento/metabolismo , Humanos , Intestino Delgado/microbiología , Trastornos Nutricionales/metabolismo , Fósforo/metabolismo
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