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1.
Rev Gastroenterol Mex (Engl Ed) ; 88(3): 220-224, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35523681

RESUMEN

INTRODUCTION: The aging of the population is one of the most widely studied and impactful social phenomena of this century. Up to 25% of all emergency hospital admissions can be due to diseases that require general surgery. AIMS: To describe the experience at the Department of Gastrointestinal Surgery of the Hospital Español, Mexico, in patients above 65 years of age. MATERIALS AND METHODS: A retrospective, observational, analytic, and cross-sectional study was conducted that included 595 medical records of geriatric patients that underwent surgical procedures, within the time frame of November 2013 and February 2019. RESULTS: A total of 52% (309) of the patients were men and 48% (286) were women. Mean patient age was 75.38 years, with a mode of 73 years, and a maximum age of 100 years. Mean hospital stay was 4.5 days. Postoperative complications presented in 12.77% of the patients, 3.02% of which were severe. Reoperation was required in 13 patients (0.02%). The perioperative mortality rate was 2.02%. CONCLUSIONS: The morbidity and mortality rates of the procedures that corresponded to general surgery in our case series were similar to those reported in the literature. A statistically significant number of patients underwent laparoscopic surgery, within the study period.

2.
Science ; 366(6469): 1143-1149, 2019 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-31780560

RESUMEN

Disruption of intestinal microbial communities appears to underlie many human illnesses, but the mechanisms that promote this dysbiosis and its adverse consequences are poorly understood. In patients who received allogeneic hematopoietic cell transplantation (allo-HCT), we describe a high incidence of enterococcal expansion, which was associated with graft-versus-host disease (GVHD) and mortality. We found that Enterococcus also expands in the mouse gastrointestinal tract after allo-HCT and exacerbates disease severity in gnotobiotic models. Enterococcus growth is dependent on the disaccharide lactose, and dietary lactose depletion attenuates Enterococcus outgrowth and reduces the severity of GVHD in mice. Allo-HCT patients carrying lactose-nonabsorber genotypes showed compromised clearance of postantibiotic Enterococcus domination. We report lactose as a common nutrient that drives expansion of a commensal bacterium that exacerbates an intestinal and systemic inflammatory disease.


Asunto(s)
Enterococcus/crecimiento & desarrollo , Microbioma Gastrointestinal , Enfermedad Injerto contra Huésped/microbiología , Trasplante de Células Madre Hematopoyéticas , Lactosa/metabolismo , Anciano , Animales , Disbiosis , Enterococcus/genética , Enterococcus/metabolismo , Heces/microbiología , Femenino , Microbioma Gastrointestinal/genética , Humanos , Intestinos/microbiología , Masculino , Ratones , Microbiota , Persona de Mediana Edad , ARN Ribosómico 16S , Análisis de Secuencia de ARN , Trasplante Homólogo
3.
Rev Neurol ; 43(1): 32-8, 2006.
Artículo en Español | MEDLINE | ID: mdl-16807870

RESUMEN

AIMS: We outline a proposal for the structural and functional features needed to develop a registry of dementias which can be used to collect standardised information that is both reliable and valid concerning cases of dementia in the specialised health care centres within a particular geographical area. DEVELOPMENT: Due to the shortage of information about aspects concerning the impact of dementias on the health care system (in terms of the usage of resources and patterns of detection, referral, diagnosis and treatment in usual clinical practice in primary and secondary care), a sequential implementation of the registry is proposed so that it can be adapted to each health district or region. The first step is to identify the cases and sources of information; second, a system for collecting data must be developed that allows information to be gathered in a standardised manner while at the same time making it possible to work in close collaboration with the specialists who diagnose dementia; and, third, it must be set up with the logistics and staff needed to centralise all the functions and activities of the registry. CONCLUSIONS: Epidemiological surveillance is an essential instrument for planning, managing and distributing community health resources, for following up the natural history of chronic diseases and for assessing the impact of programmes of prevention. In this respect, and from a functional point of view, the proposed registry of dementias meets all the basic requirements of epidemiological surveillance.


Asunto(s)
Demencia , Vigilancia de la Población , Sistema de Registros , Demencia/clasificación , Demencia/diagnóstico , Demencia/epidemiología , Planificación en Salud , Humanos , Sistemas de Información , Salud Pública
4.
Clin Endocrinol (Oxf) ; 57(1): 131-4, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12100081
5.
Acta cancerol ; 29(1): 26-30, jul. 1999. tab
Artículo en Inglés | LILACS, LIPECS | ID: lil-267225

RESUMEN

El papilomavirus humano (PVH es considerado uno de los principales factores involucrados en la génesis del cáncer del cuello uterino. El ADN del PVH se detectó empleando la reacción en cadena de la polimerasa (RCP) en 53 mujeres con citología previa de lesión escamosa intraepitelial de bajo grado (LEI) en célula cérvicovaginales obtenidas empleando el lavado cérvicovaginal y el escobillo cervical. En 35 mujeres (66.0 por ciento) los resultados fueron positivos con el método de lavado cervicovaginal, de las cuales sólo 18 de ellas fueron también positivas en las muestras obtenidas con escobillado. Ninguna de las mujeres tuvo ADN del PVH detectado en el escobillado sin haber sido detectado en el lavado cérvicovaginal. En el lavado encontramos 12 infecciones simples y 23 múltiples y en el escobillado detectamos 7 y 8 infecciones simples y múltiples respectivamente. El tipo viral mas frecuente en las muestras del lavado fue el PVH-18 (57.1 por ciento), y en las de escobillado el PVH-16 (93.3 por ciento). Comparando los resultados del lavado y escobillado ADN/PVH positivo con el diagnóstico citológico observamos mayor positividad con el método de lavado, así mismo con algunos factores epidemiológicos como la edad de inicio de la actividad sexual, poliandria y paridad se detectó también mayor positividad en las muestras de lavado. Concluimos que el lavado cérvicovaginal es un buen método de colección de células para detectar ADN del PVH en mujeres aparentemente sanas y para minimizar el sesgo en los estudio clínicos con el diagnóstico molecular.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Papiloma , Sondas de ADN de HPV , Neoplasias del Cuello Uterino , Neoplasias de Cabeza y Cuello
6.
Dig Dis Sci ; 43(11): 2384-91, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9824123

RESUMEN

The aim of this study was to investigate abnormalities in pediatric patients with functional dyspepsia. Fifteen symptomatic pediatric patients diagnosed with functional dyspepsia and 17 aged-matched healthy controls were studied. Gastric myoelectrical activity was recorded using surface electrogastrography for 1 hr in the fasting state and 1 hr after a test meal. It was found that, in comparison with the controls, the children with functional dyspepsia had a lower percentage of 2- to 4-cpm slow waves in both fasting state (66.0+/-4.7% vs 79.7+/-3.1%, P < 0.07) and fed state (72.4+/-5.4% vs 85.0+/-2.9%, P < 0.04), and a significantly higher instability of the dominant frequency in both fasting state (0.50+/-0.05 vs 0.31+/-0.04, P < 0.01) and fed state (0.39+/-0.05 vs 0.25+/-0.03, P < 0.05). It was also found the postprandial increase in EGG dominant power in the patients was inversely correlated with the total symptom score (r = 0.63, P = 0.03). It was concluded that abnormal gastric myoelectrical activity may play a role in the pathogenesis of pediatric functional dyspepsia.


Asunto(s)
Dispepsia/fisiopatología , Complejo Mioeléctrico Migratorio/fisiología , Adolescente , Niño , Preescolar , Electrodos , Electrodiagnóstico/instrumentación , Electrodiagnóstico/métodos , Electrodiagnóstico/estadística & datos numéricos , Ayuno/fisiología , Femenino , Humanos , Masculino , Periodo Posprandial , Valores de Referencia , Procesamiento de Señales Asistido por Computador/instrumentación , Estadísticas no Paramétricas , Estómago/fisiopatología
7.
Acta cancerol ; 28(2): 54-60, nov. 1998. tab, graf
Artículo en Español | LILACS, LIPECS | ID: lil-267222

RESUMEN

Los estudios citogenéticos y genéticos moleculares han confirmado que en el desarrollo y la progresión de las neoplasias malignas están involucrados cambios del material genético. En el cáncer de cuello uterino se han descrito aberraciones en los cromosomas; en la literatura hay algunos reportes de alteraciones cromosómicas en el cariotopo de los linfocitos perifericos en pacientes con cáncer. El objetivo del presente trabajo fue estudiar simultaneamente el cariotipo de las células tumorales y linfocitos de sangre periférica en las pacientes con cáncer de cuello uterino. Se estudiarón 68 pacientes atendidas en el Departamento de Detección y diagnóstico del Instituto de Enfermedades Neoplásicas, desde mayo de 1993 hasta agosto de 1997. El estudio citogenético se efectuó de acuerdo a la metodología de Verma y Babu. Las alteraciones más frecuentes fueron a) estructurales a nivel del cromosoma 1 en el 36.76 por ciento y del cromosoma 3 en el 20.58 por ciento y b)numéricas mayores de 46 cromosomas (25 por ciento) y menores de 46 cromosomas (30.88 por ciento). Se observaron otras alteraciones como trisomía 19, monosomía del gonosoma X y dobles minutos. El cariotipo de los linfocitos de la sangre periférica fue normal en número, en estructura y distribución. Se hace hincapié en el hallazgo de que los 4 casos estudiados de adenocarcinoma tenían un número menor de 46 cromosomas en el cariotipo tumoral y se sugiere el estduio de una casuística mayor para ver si esta es una característica de este tipo tumoral. Se concluye que las alteraciones encontradas están de acuerdo en mucho a lo que ha sido descrito en la literatura y que debe estudiar un número mayor de casos tratando de correlacionar las alteraciones cromosómicas con la respuesta al tratamiento y el pronóstico igualmente si algunas alteraciones tienen correlación con el grado histólogico del tumor, y si los mismos cambios se ven tanto en las lesiones precursoras como en enfermedad avanzaa. También se sugiere estudiar el cariotipo de los linfocitos de la sangre de pacientes con alto riesgo de desarrollar cáncer y en pacientes con neoplasias múltiples.


Asunto(s)
Humanos , Adulto , Persona de Mediana Edad , Femenino , Linfocitos , Neoplasias del Cuello Uterino , Cromosomas , Cariotipificación , Citogenética
8.
Aten Primaria ; 21(2): 65-74, 1998 Feb 15.
Artículo en Español | MEDLINE | ID: mdl-9608129

RESUMEN

OBJECTIVES: To translate into Castilian (Spanish) and measure the validity of the ECBI (Eyberg Child Behaviour Inventory), a questionnaire to screen behavioural disorders in pre-school children. DESIGN: Translation and back-translation of the ECBI. A descriptive crossover study. SETTING: Primary Care Paediatrics. PATIENTS: All the 3, 4 and 5-year olds from 4 paediatric clinics at 4 Health Centres (n = 527). One refusal. MEASUREMENTS AND MAIN RESULTS: The questionnaire was filled in by the children's mothers and was repeated 20 days afterwards for 35 children. High coefficients of internal consistency (Cronbach's alpha = 0.87) and stability (intragroup correlation = 0.89 [0.78-0.94]) were obtained. There was good factorial validity, as 84% of the variance was explained by the four factors with value greater than 1. CONCLUSIONS: The Spanish version of the ECBI is a brief and easy questionnaire with good results in psychometric assessment. Therefore, it can be recommended for use in paediatric Primary Care in order to detect children with behavioural problems.


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Conducta Infantil , Psicometría , Factores de Edad , Preescolar , Estudios Cruzados , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Atención Primaria de Salud , España , Encuestas y Cuestionarios
9.
Am J Physiol ; 272(5 Pt 1): G1022-7, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9176209

RESUMEN

The aim of this study was to investigate the developmental change of gastric myoelectrical activity in humans. Five groups of healthy subjects were studied, including 10 preterm newborns, 8 full-term newborns, 8 full-term infants (ages 2-6 mo), 9 children (ages 4-11 yr), and 9 adults. Gastric myoelectrical activity was recorded using surface electrogastrography for 30 min before and 30 min after a test meal in each subject. Spectral analysis methods were applied to compute the parameters of the electrogastrogram (EGG). The results showed that the percentage of 2- to-4-cycles/min (cpm) slow waves was 26.6 +/- 3.9% in the preterm newborns, 30.0 +/- 4.0% in full-term newborns, 70 +/- 6.1% in 2- to 6-mo-old infants (P < 0.001 compared with newborns), 84.6 +/- 3.2% in 4- to 11-yr-old children (P < 0.03 compared with infants), and 88.9 +/- 2.2% in the adults (P > 0.05 compared with children). In conclusion, gastric slow waves are absent at birth, and there is a maturing process after birth. Age-matched controls are necessary for the interpretation of EGG data from neonates and infants, whereas EGG data in children are the same as in adults.


Asunto(s)
Envejecimiento/fisiología , Músculo Liso/fisiología , Estómago/fisiología , Adulto , Niño , Desarrollo Infantil , Preescolar , Electrofisiología/instrumentación , Equipos y Suministros , Femenino , Humanos , Recién Nacido , Masculino , Persona de Mediana Edad
10.
J Okla State Med Assoc ; 90(3): 89-93, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9097497

RESUMEN

Living related liver transplantation (LRLT) presents several advantages as compared to cadaveric liver transplantation, and it has become an increasingly popular option for children with end-stage liver diseases. Since 1995, five LRLT procedures have been performed at the authors' facility. Recipients were three boys and two girls, whose mean age was 2.6 years. Recipients' primary diagnoses were primary hyperoxaluria (PH) (n = 3), Alagille's syndrome (n = 1), and Byler's disease (n = 1). Left lateral segments harvested from their parents were used as the liver grafts on all patients. The donors included three mothers and two fathers, with a mean age of 29 years. Tacrolimus with steroids was used as immunosuppressive therapy. In all cases (mean follow-up time of 11 months), graft function was excellent and four children are doing very well. One boy died of post-transplant lymphoproliferative disorder (PTLD) 7 months after LRLT. All donors are doing very well with no postoperative complications. The authors believe that LRLT is a safe procedure for both the donor and the recipient, and provides, in children, an excellent alternative to cadaveric liver transplantation.


Asunto(s)
Trasplante de Hígado/métodos , Donadores Vivos , Adulto , Preescolar , Femenino , Estudios de Seguimiento , Supervivencia de Injerto/fisiología , Humanos , Lactante , Pruebas de Función Hepática , Trasplante de Hígado/fisiología , Masculino , Oklahoma
12.
Acta cancerol ; 26(1): 3-6, mar. 1996. tab
Artículo en Español | LILACS, LIPECS | ID: lil-177949

RESUMEN

Las fichas clínicas de 142 mujeres con infección cervical subclínica por PVH de cuello uterino, confirmadas histológicamente, que acudieron al Departamento de Detección y Diagnóstico del INEN, desde enero de 1991 a diciembre de 1993, fueron revisadas, para estudiar algunos aspectos clínico-epidemiológicos. El promedio de edad fue 35.8 años con un rango más frecuente de 20 a 49 años. La proporción de procedencia de mujeres de los diferentes distritos de Lima fue similar. El 1.6 por ciento era analfabeta. La unión conyugal se halló en el 85.9 por ciento. El 63.1 por ciento tuvo su primera relación sexual antes de los 20 años. casi la totalidad de mujeres no usó método de barrera. La localización anatómica más frecuente fue el labio anterior. El epitelio blanco característico de PVH fue la imagen colposcópica más frecuente. Este grupo de mujeres será considerada una cohorte y es importante el estudio de ADN y la tipificación del PVH para confirmar o rechazar la infección subclínica por PVH de cuello uterino. Este ha sido uno de los motivos para realizar un Protocolo de Investigación de la infección por PVH de cuello uterino mediante el estudio molecular de ADN que se está desarrollando en este departamento


Asunto(s)
Masculino , Femenino , Persona de Mediana Edad , Papiloma/fisiopatología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/virología
13.
Acta cancerol ; 25(1): 7-12, mar. 1995. ilus
Artículo en Español | LILACS, LIPECS | ID: lil-177916

RESUMEN

El cáncer de cuello uterino es la neoplasia más frecuente en la mujer peruana y representa uno de los principales problemas de salud pública en nuestro medio. La causa del cáncer de cuello uterino es considerada multifactorial, siendo la edad temprana de la primera relación sexual y la poliandria, reportadas como los factores de riesgo más importantes. Entre enero de 1988 y julio de 1990 en el Departamento de Detección y Diagnóstico, del Instituto Nacional de Enfermedades Neoplásicas se diseñó un estudio de casos y controles, con la finalidad de determinar el perfil del riesgo de cáncer de cuello uterino de la mujer peruana. Se estudió 644 personas: 161 parejas casos y 161 parejas controles, con la finalidad de evaluar los factores de riesgo de cáncer de cuello uterino, analizándose edad, vida sexual, alimentación, higiene sexual, hábitos, uso de anticonceptivos, antecedentes de Papanicolau y enfermedades venéreas previas, entre otros factores. Los datos se analizaron usando un modelo de "regresión logística multivariante" para un estudio de caso-control. Al inicio del análisis hubieron 27 variables para los hombres y 17 para las mujeres, habiéndose reducido el número de ellas -sin perder información- al emplearse un análisis de "componentes principales". "La regresión logística multivariante" estableció que los factores de riesgo más importantes fueron: abortos antes del primer parto (APP), número de gestaciones (NGES), edad de la primera relación sexual de la mujer (EPRS), uso del preservativo por parte del hombre (PRESERV), edad de la menarquia (MENR) y número de abortos (ABORT). Para estos factores se obtuvieron los ODDS RATIOS siguientes: a) No uso de preservativo. OR:4.938 (IC 95 por ciento, 1.82-13.39); b) APP,OR: 2.815 (IC 95 por ciento, 1.25-6.29); c) EPRS, OR:2.483 (IC 95 por ciento, 1.564-3.94) y NGES. OR, 1.945 (IC 95 por ciento, 1.20-3.13). Los resultados del presente estudio sugieren que el cáncer de cuello uterino puede ser una enfermedad de transmisión sexual


Asunto(s)
Humanos , Masculino , Femenino , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/etiología , Perú/epidemiología , Neoplasias del Cuello Uterino/prevención & control , Neoplasias del Cuello Uterino/epidemiología
14.
Am J Dis Child ; 141(10): 1069-71, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3630992

RESUMEN

Soy protein formulas are often poorly tolerated by infants with chronic nonspecific or postinfectious diarrhea syndrome. We found that these adverse responses may be prevented by using lactose, instead of sucrose or dextrimaltose, in soy formula. We studied 40 infants diagnosed as soy intolerant. They were given soy formula with differing carbohydrate contents in a randomized, blinded prospective study. Stool output, stool sodium content, and symptoms were significantly improved in infants receiving a soy-lactose formula; no difference was seen in formulas with sucrose or maltose. Improvement occurred in three to five days in most infants. Furthermore, the characteristic frequency distribution of the favorable response to lactose suggested a specific mechanism for the inhibition of water and electrolyte losses through the bowel. The results indicate that, in the absence of lactose intolerance, a soy-lactose formula could be useful in treating chronic diarrhea and secondary protein intolerance.


Asunto(s)
Diarrea/dietoterapia , Glycine max , Alimentos Infantiles , Lactosa/administración & dosificación , Enfermedad Crónica , Diarrea/etiología , Humanos , Lactante , Glycine max/efectos adversos
15.
Biochim Biophys Acta ; 914(2): 143-51, 1987 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-3607068

RESUMEN

Studies were performed to identify rat intestinal microvillar proteins which undergo changes in terminal glycosylation during postnatal development. Pulse-labeling with [3H]fucose or N-[3H]acetylgalactosamine showed significantly higher incorporation into purified microvillar membranes of weanling than suckling rats. In contrast, the incorporation of [3H]sialic acid after pulse-labeling with N-[3H]acetylmanosamine was higher in suckling rats. SDS-polyacrylamide gel electrophoresis revealed these developmental differences in radioactive sugar incorporation to involve mainly proteins above Mr 90,000. 125I-labeled peanut lectin autoradiography revealed an Mr greater than 330,000 binding protein in suckling rats. Neuraminidase treatment of the membranes revealed the presence of sialyl-substituted sites in this protein in suckling, weaning and weanling animals, but the unmasking of sites decreased with advancing maturation. 125I-labeled Ulex europeus I autoradiography showed marked increases in binding of this lectin to Mr 66,000, 92,000, 130,000, 150,000 and greater than 330,000 proteins from weaning to weanling periods. Similar age-related increases in soybean lectin binding to Mr 130,000-150,000, and greater than 330,000 proteins were demonstrated by affinity chromatography. The Mr values of the major lectin-binding proteins were close to those reported for several hydrolases (trehalase, alkaline phosphatase, sucrase-isomaltase and glucoamylase). Comparison of the Coomassie blue-stained electrophoretograms from each age-group against the corresponding autoradiograms of lection-binding proteins led us to conclude that, while the content of these proteins in the membrane achieve their mature levels at or before weaning, their terminal glycosylation (desialylation, fucosylation, N-acetylgalactosamination) is not fully established until later development.


Asunto(s)
Glicósido Hidrolasas/metabolismo , Hidrolasas/metabolismo , Intestino Delgado/crecimiento & desarrollo , Microvellosidades/enzimología , Envejecimiento , Animales , Fraccionamiento Celular , Glicoproteínas/biosíntesis , Glicoproteínas/aislamiento & purificación , Intestino Delgado/enzimología , Microvellosidades/ultraestructura , Peso Molecular , Ratas , Ratas Endogámicas , Ácidos Siálicos/análisis
16.
Pediatr Res ; 19(9): 899-902, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3900901

RESUMEN

Cortisone, thyroxine, epidermal growth factor, or insulin were administered to 8-day-old rats for 4 days. In comparison to saline-injected controls, cortisone treatment: 1) lowered the sialic acid and raised the fucose content of the intestinal microvillus membranes, 2) increased [3H]fucose incorporation into these membranes, and 3) decreased the membrane binding of 125I-wheat germ agglutinin, while increasing the binding of 125I-ulex europeus agglutinin I and 125I-peanut agglutinin. Thyroxine treatment had similar effects on fucose content and 125I-ulex europeus agglutinin I binding, but did not alter [3H] fucose incorporation or sialic acid content. At the doses used, epidermal growth factor and insulin had no significant effects. The effect of cortisone treatment on sialic acid and fucose was commensurate with a 5- to 6-day acceleration of postnatal intestinal maturation. The changes in lectin binding, however, suggested qualitative differences between developmental and cortisone-induced membrane glycosylation. In addition, this study demonstrates significant quantitative and qualitative differences in the response of intestinal glycosylation to pharmacologic doses of the four hormones.


Asunto(s)
Grupos de Población Animal/metabolismo , Animales Lactantes/metabolismo , Fucosa/metabolismo , Hormonas/farmacología , Intestino Delgado/metabolismo , Microvellosidades/metabolismo , Ácidos Siálicos/metabolismo , Animales , Cortisona/farmacología , Factor de Crecimiento Epidérmico/farmacología , Insulina/farmacología , Lectinas , Ácido N-Acetilneuramínico , Ratas , Ratas Endogámicas , Tiroxina/farmacología
17.
Pediatr Res ; 19(8): 868-72, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4034289

RESUMEN

The purpose of this work was to assess the toxic lectin ricin (RCAII) as a probe for the study of intestinal permeability in the developing small bowel. Jejunal explants from suckling and adult rabbits were exposed to varying dosages of RCAII for 30 min at 25 degrees C and then cultured in toxin-free medium. The RCAII dose required to inhibit protein synthesis during 6 h of culture increased from 0.1 microgram/ml in 4-day-old rabbits to 25 micrograms/ml in weanling rabbits. RCAII cytotoxicity was almost completely blocked by 0.1 M lactulose in all age groups. The kinetics of 125I-RCAII binding to purified microvillus membranes were determined by incubating a fixed concentration of membrane protein (30 micrograms) with increasing concentrations of labeled lectin (2-18 micrograms/ml). Binding attained saturation with adult but not with suckling animal membranes. The latter yielded a curvilinear relationship in Scatchard plots, suggesting either several classes of binding sites or negative cooperativity. RCAII binding was confined to the delipidated fraction of the membranes and decreased by 42% from 6 days old to adult age. The extreme sensitivity of colostral epithelium to RCAII is probably related to the high level of endocytosis exhibited by the immature membrane of suckling rabbits. The development of increasing resistance to the toxin, and associated decrease in binding, might be related to disappearance of saccharide sites in productive surface receptors occurring in the developmental course of intestinal glycosylation.


Asunto(s)
Yeyuno/crecimiento & desarrollo , Ricina/toxicidad , Animales , Radioisótopos de Yodo , Yeyuno/efectos de los fármacos , Biosíntesis de Proteínas , Conejos , Ricina/metabolismo , Destete/efectos de los fármacos
18.
Biochem Biophys Res Commun ; 125(2): 546-53, 1984 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-6517912

RESUMEN

We present evidence of a change from sialylation to fucosylation of intestinal microvillus membrane oligosaccharides during postnatal development in the rat. The initial high sialic acid to fucose molar ratio in native and delipidated membranes was completely reversed after weaning. The specific binding of 125I-labeled wheat germ agglutinin to neuraminidase-sensitive sites in the native and delipidated membranes decreased markedly from early suckling to weaning ages. The binding of 125I-labeled Ulex europeus agglutinin I showed an age-related pattern opposite to that of wheat germ agglutinin. The changes in membrane reactivities to these lectins were entirely consistent with the existence of a developmentally-controlled shift from terminal sialyl to fucosyl substitutions among various glycoconjugate classes. This could play a key role on the functional transformation experienced by the intestinal epithelium of suckling rats.


Asunto(s)
Intestino Delgado/crecimiento & desarrollo , Microvellosidades/metabolismo , Oligosacáridos/biosíntesis , Polisacáridos/biosíntesis , Envejecimiento , Animales , Fucosa/análisis , Intestino Delgado/metabolismo , Lectinas , Ácido N-Acetilneuramínico , Neuraminidasa , Ratas , Ratas Endogámicas , Ácidos Siálicos/análisis
19.
Life Sci ; 35(24): 2415-9, 1984 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-6513722

RESUMEN

The transport of manganese from extrinsically labeled human milk, bovine milk and infant formula was studied by the everted intestinal sac method. Tissue/mucosal flux data indicated that transport of manganese into the intestinal tissue was significantly greater with bovine milk and formula than from human milk. Similarly, the total flux of manganese from the mucosal to serosal surface was less when human milk was used. Smaller molecular weight manganese binding ligands isolated from the milk samples enhanced the mucosal to tissue movement of manganese as contrasted to the higher molecular weight manganese binding ligands. Most significantly the data suggest that the transport and uptake of manganese is less in the presence of human milk and its isolated manganese fractions than it is in bovine milk or infant formula.


Asunto(s)
Alimentos Infantiles/análisis , Yeyuno/metabolismo , Manganeso/metabolismo , Leche Humana/análisis , Leche/análisis , Animales , Disponibilidad Biológica , Transporte Biológico , Bovinos , Humanos , Mucosa Intestinal/metabolismo , Ligandos , Masculino , Peso Molecular , Ratas , Ratas Endogámicas
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