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1.
Microb Pathog ; 156: 104902, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33930421

RESUMEN

Biological detergents are used in research laboratories, to extract or solubilize proteins from cell membranes. In order to evaluate the ability to extract antigens from the bacterial cell surface of the wild Vibrio cholerae strain C7258 and study their immunogenic potential by forming proteoliposomes and cochleate and preserving their immunogenicity, the non-ionic detergent, n-Octylglucoside (n-OG), and the Zwitterionic detergent (3-cholamidopropyl dimethylammonio 1-propanesulfonate; CHAPS) were tested in concentrations between 5 and 15%. The anionic detergent sodium deoxycholate (DOC) was used as a reference. Electrophoretic, immunochemical and electron microscopy techniques have characterized the extracts and their chromatographic fractions. With CHAPS and n-OG detergents in concentrations between 5 and 15%, a higher yield was obtained in the extraction of proteins and lipopolysaccharides (LPS) and other components from the bacterial surface compared to 10% DOC. When using 10% DOC, 15% CHAPS and n-OG between 5 and 15%, stable proteoliposomes were formed, of average size between 82 and 93 nm in diameter, with known proportions of proteins, LPS and other components. In some of the concentrations, liposomes were formed with almost pure proteins. Some cholera outer membrane proteins like the 17 kDa protein, which corresponds to the mannose-sensitive hemagglutinin (MSHA), which mediates the adhesion to the brush border of the small intestine and the outer membrane protein U (OMPU) were identified with monoclonal antibodies (mAbs) and purified. The fundamental components of liposomes, proteins and LPS, retained their molecular weights, when compared with known standards and by processing programs of electrophoretic profiles and their antigenicity, without alterations due to the extraction procedure, as could be verified by immune identification techniques with monoclonal antibodies in the case of LPS, significant antigens in this pathogen. The main purpose of the present work was to show that a new anticholera vaccine formulation based on cochleates, containing selected protein and LPS fraction extracted by detergents, is able to elicit protective high titers of bactericidal antibodies after intragastric immunization in the mice model. The objective was achieved.


Asunto(s)
Vacunas contra el Cólera , Cólera , Vibrio cholerae , Animales , Anticuerpos Antibacterianos , Antígenos Bacterianos , Inmunización , Ratones
2.
Eur J Pediatr ; 180(3): 783-790, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32827275

RESUMEN

During neonatal resuscitation in the delivery room, heart rate guides clinical intervention, and although different methods have been evaluated as auscultation, pulse oximetry, and electrocardiography, they have various limitations. This was a prospective observational study which aim was to evaluate the accuracy and speed of ultrasound for measuring neonatal heart rate compared with stethoscope, pulse oximetry, and electrocardiography. Simultaneous determinations of heart rate using stethoscope, ultrasound, pulse oximetry, and electrocardiography were performed. Fifty term newborns were included. There were no differences according to the turn on time of the ultrasound, pulse oximetry, and electrocardiography (p = 0.666), but the placement time and the detection time from birth were shorter for ultrasound (p < 0.001). A stronger positive correlation was detected between ultrasound and electrocardiography at 90 (Rho = 0.926), and 120 s (Rho = 0.920) with p < 0.001. The Bland-Altman analysis showed a bias of - 2.23 (p = 0.129) between ultrasound and electrocardiography at 90 s, and a bias of 0.44 (p = 0.092) at 120 s. Instead, the bias between auscultation and electrocardiography at 90 s was - 6.71 (p = 0.131), and at 120 s was of - 4.67 (p = 0.793).Conclusions: Ultrasound is a fast method to detect heart rate in the delivery room and has a good correlation with stethoscope and electrocardiography. What is Known: • During neonatal resuscitation in the delivery room, heart rate guides clinical intervention, and although different methods have been evaluated, they have various limitations. What is New: • Heart rate ultrasound is a good and fast method to detect HR in the delivery room with a good correlation with electrocardiography and stethoscope.


Asunto(s)
Salas de Parto , Resucitación , Electrocardiografía , Femenino , Frecuencia Cardíaca , Humanos , Recién Nacido , Oximetría , Embarazo
3.
J Microbiol Methods ; 176: 106003, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32702386

RESUMEN

Mycobacterium tuberculosis (Mtb) is a pathogenic bacterium that causes tuberculosis (TB). This contagious disease remains a severe health problem in the world. The disease is transmitted via inhalation of airborne droplets carrying Mtb from TB patients. Early detection of the disease is vital to prevent transmission of the infection to people in close contact with the patients. To date, there is a need of a simple, rapid, sensitive and specific diagnostic test for TB. Previous studies showed the potential of Mtb 16 kDa antigen (Ag16) in TB diagnosis. In this study, lateral flow immunoassay, also called simple strip immunoassay or immunochromatographic test (ICT) for detection of Ag16 was developed (Mtb-strip) and assessed as a potential rapid TB diagnosis method. A monoclonal antibody against Ag16 was optimized as the capturing and detection antibody on the Mtb-strip. Parameters affecting the performance of the Mtb-strip were also optimized before a complete prototype was developed. Analytical sensitivity showed that Mtb-strip was capable to detect as low as 125 ng of purified Ag16. The analytical sensitivity of Mtb-strip suggests its potential usefulness in different clinical applications.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Cromatografía de Afinidad/métodos , Pruebas Diagnósticas de Rutina/métodos , Tuberculosis/diagnóstico , Humanos , Mycobacterium tuberculosis/inmunología , Mycobacterium tuberculosis/aislamiento & purificación , Sensibilidad y Especificidad
4.
Rev. chil. neuro-psiquiatr ; 58(4): 438-446, dic. 2020. ilus, tab
Artículo en Español | LILACS | ID: biblio-1388366

RESUMEN

INTRODUCCIÓN: La estimulación cerebral profunda (DBS) se ha propuesto como una alternativa terapéutica para el manejo de la depresión resistente al tratamiento (DRT). Sin embargo, existen múltiples blancos para neuroestimulación y se desconoce el punto neuroanatómico óptimo en esta patología. Como parte del circuito de recompensa, el núcleo accumbens (NAc) ha sido estudiado en modelos de depresión y anhedonia. El objetivo de este artículo fue describir la experiencia clínica de la implantación de electrodos bilaterales de DBS en el NAc. REPORTE DE CASOS: Se describe la experiencia en cuatro mujeres entre los 17 a 41 años con DRT. Los casos presentaban antecedente de múltiples hospitalizaciones e intentos de suicidio serios, a pesar de haber sido tratadas previamente con terapia farmacológica, psicoterapia y TECAR (Terapia electroconvulsiva con anestesia y relajación). A los 6 meses del inicio del DBS, se observó una mejoría de los síntomas depresivos en la escala de Hamilton y un incremento en la escala de funcionalidad global. La anhedonia y la abulia persistieron luego de la cirugía, aunque con menor intensidad. CONCLUSIÓN: La DBS del NAc puede ser una estrategia efectiva en el tratamiento de pacientes con DRT, impactando en la funcionalidad y en la disminución del riesgo suicida.


INTRODUCTION: Deep brain stimulation (DBS) has been proposed as a therapeutic alternative for Treatment-resistant depression (TRD) patients. However, there are multiple targets for neurostimulation and the optimal neuroanatomical landmark for this pathology is unknown. Nucleus accumbens (NAc) is a crucial part of the reward circuit and has been studied extensively in models of depression and anhedonia. The objective of this study was to describe our clinical experience with DBS of the NAc patients with TRD. CASE SERIES: It described the experience in four females between 17 and 41 years of age. All cases presented with a history of multiple hospitalizations and serious suicide attempts, despite having been treated with optimal pharmacological regimes, psychotherapy and ECT (Electroconvulsive therapy). Six months after the initiation of DBS, an improvement in the Hamilton Depression Scale and in the Global Assessment of Functioning Scale was observed. Anhedonia and abulia persisted after the surgery, although less severe. CONCLUSION: DBS of NAc seems to offer favorable surgical outcomes in patients with TRD, impacting functionality and suicidal risk.


Asunto(s)
Humanos , Femenino , Adolescente , Adulto , Adulto Joven , Estimulación Encefálica Profunda/métodos , Trastorno Depresivo Resistente al Tratamiento/terapia , Núcleo Accumbens , Intento de Suicidio/prevención & control
5.
J Parasitol ; 84(1): 55-61, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9488338

RESUMEN

This report contains a partial characterization of the epitope recognized by monoclonal antibody (MAb) ES78 produced against excretory-secretory (ES) antigens of Fasciola hepatica. ES78 is currently used for the detection of ES antigens in serum and stool samples of cattle and humans with fasciolosis, using a highly sensitive and specific sandwich enzyme-linked immunosorbent assay (ELISA). The epitope was characterized by periodate oxidation, alkaline borohydride reduction, trichloroacetic acid precipitation, beta-mercaptoethanol treatment, and enzymatic proteolysis. These results, together with those of the 2-site ELISA, lectin immunoassays, and beta-galactosidase digestion, showed that MAb ES78 reacts with a partly protein/partly carbohydrate antigenic determinant that is found on several ES molecules of adult specimens of F. hepatica and contains at least 1 disulfide bond and beta-galactose probably as galactose-beta(1-3)-N-acetylgalactosamine disaccharide.


Asunto(s)
Anticuerpos Antihelmínticos/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos Helmínticos/química , Fasciola hepatica/inmunología , Animales , Antígenos Helmínticos/inmunología , Antígenos Helmínticos/aislamiento & purificación , Borohidruros/farmacología , Bovinos , Cromatografía de Afinidad , Ensayo de Inmunoadsorción Enzimática , Epítopos/química , Epítopos/inmunología , Epítopos/aislamiento & purificación , Calor , Inmunoensayo , Lectinas/metabolismo , Mercaptoetanol/farmacología , Neuraminidasa/metabolismo , Ácido Peryódico/farmacología , Pronasa/metabolismo , Ácido Tricloroacético/farmacología , beta-Galactosidasa/metabolismo
6.
Hybridoma (Larchmt) ; 25(4): 243-7, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16934022

RESUMEN

Neisseria meningitidis isolates are conventionally classified by serosubtyping, which characterizes the reactivities of the PorA outer membrane protein variable-region epitopes with monoclonal antibodies (MAbs). New murine hybridomas, secreting specific MAbs against PorA of N. meningitidis serogroup B, were generated using conventional hybridoma procedures. Using outer membrane protein as antigen, we obtained two positive clones, and one of them we characterized. This MAb reacted, on whole-cell enzyme-linked immunosorbent assay (ELISA) and immunoblotting, only with strain subtype P1.15 and its IgG2b isotype. This MAb demonstrated bactericidal activity against the homologous strain in the presence of human complement.


Asunto(s)
Anticuerpos Monoclonales/metabolismo , Vacunas Bacterianas/inmunología , Neisseria meningitidis/inmunología , Porinas/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Monoclonales/química , Femenino , Hibridomas , Ratones , Ratones Endogámicos BALB C
7.
Cardioscience ; 2(1): 63-9, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1888881

RESUMEN

We have applied M-mode and two-dimensional echocardiography to infants living at high altitude in La Paz, Bolivia (3800m) and infants living at low altitude in Santa Cruz, Bolivia (400m). At low altitude, the thickness of the anterior wall of the right ventricle decreases during the first month of extrauterine life to a dimension which remains constant for the rest of infancy. At high altitude, the thickness of the anterior wall of the right ventricle at birth is similar to that found at low altitude but does not decrease in the succeeding twelve months. The ratio of the diameter of the aorta to that of the pulmonary artery was higher at low altitude in all age-groups. The observations are consistent with the persistence of a high pulmonary arterial pressure during infancy at high altitude.


Asunto(s)
Altitud , Tabiques Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Corazón/crecimiento & desarrollo , Adaptación Fisiológica , Aorta/diagnóstico por imagen , Bolivia , Ecocardiografía , Ventrículos Cardíacos/crecimiento & desarrollo , Humanos , Hipoxia/diagnóstico por imagen , Lactante , Recién Nacido , Arteria Pulmonar/diagnóstico por imagen
8.
Rev Cubana Med Trop ; 50(1): 12-7, 1998.
Artículo en Español | MEDLINE | ID: mdl-9842261

RESUMEN

This paper was aimed at identifying the main components present in the excretory-secretory antigens of adult parasite which are recognized by the sera of rats experimentally infected with metacercariae of Fasciola hepatica, by using the Western Blot technique. The cynetics of antibodies was also determined with and indirect ELISA. The results obtained allowed to find 31 components with approximate molecular weights from 11 to 136 kD. The predominant fractions were the following: 11-13 kD, 14-16 kD, 23-33 kD, 55-57 kD, 65-71 kD, and 86-136 kD. Antibodies were detected from the 2nd. week of infection in 80% of the animals and from the 3rd. week in 100% of them. There were no antibodies during the first week. The identification of these antibodies may contribute to a better understanding of the mechanisms of immunity linked with the infection by F. hepatica.


Asunto(s)
Anticuerpos Antihelmínticos/análisis , Fasciola hepatica/inmunología , Animales , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Peso Molecular , Ratas , Ratas Wistar
9.
Rev. chil. radiol ; 14(2): 62-67, 2008. ilus, tab
Artículo en Español | LILACS | ID: lil-517430

RESUMEN

Background. Giant cell tumor (GCT) is an uncommon primary bone neoplasm in pediatric patients. Plain radiograph of the affected area is the first diagnostic approach in most cases. Objective. To show radiographic features that could allow the radiologist to suspect the diagnosis of GCT through plain radiological study. Methods. Records from the National Bone Tumor File between 1959 and 1999 were retrospectively analyzed. Twenty-nine cases of patients under 20 years with biopsy proven diagnosis of GCT were found. The radiological study was available in 14 cases. Results. From a total of 29 patients, 83 percent were females and 17 percent males. Age ranged from 7 to 19 years, with an average of 16.3 years. In cases with radiological study, 93 percent of them presented epiphyseal involvement of long bones. Osteolytic lesions with metaphyseal extension were the most frequent radiological pattern. One case showed malignancy with metastases. Conclusions. GCT is regarded as an infrequent occurrence in pediatric patients and its diagnosis can be suspected based on plain radiographic findings.


El tumor de células gigantes es un tumor óseo primario, poco frecuente en población pediátrica. En la mayoría de los casos, la radiografía simple es la primera aproximación diagnóstica, por lo que nuestro objetivo es mostrar las características radiológicas que permiten sospechar el diagnóstico del tumor de células gigantes en el estudio radiológico simple. Se analizó retrospectivamente los datos del Registro Nacional de Tumores Óseos, entre los años 1959 y 1999, encontrando 29 casos de tumor de células gigantes histológicamente confirmados en menores de 20 años; en 14 se dispuso de estudio radiológico. El 83 por ciento (24/29) correspondió a mujeres y 17 por ciento (5/29) a hombres, con edades entre 7 y 19 años (promedio = 16.3 años). Radiológicamente, el 93 por ciento mostró compromiso epifisiario de huesos largos y el patrón más frecuente fue osteolítico con extensión metafisiaria.


Asunto(s)
Humanos , Masculino , Adolescente , Femenino , Niño , Neoplasias Óseas , Tumor Óseo de Células Gigantes , Neoplasias Óseas/patología , Estudios Retrospectivos , Tumor Óseo de Células Gigantes/patología
10.
Rev. chil. radiol ; 13(3): 109-121, 2007. ilus
Artículo en Español | LILACS | ID: lil-627510

RESUMEN

Vascular anomalies include different pathologies as hemangiomas and vascular malformations, however they usually are reported together and confusion is created. Mülliken and Glowacki proposed a classification posteriorly, modificated, adapted and actually in use. Unfortunately is not sufficiently known for our radiologist. Classification and imaging correlation of soft-tissue vascular anomalies are revised, since a exact diagnosis is a great value for appropriate treatment and prognosis.


Las anomalías vasculares han sido tradicionalmente tratadas en conjunto aun cuando engloban patologías tan diferentes como hemangiomas y malformaciones vasculares. La clasificación dada a conocer por Mülliken y Glowacki, modificada posteriormente, no es suficientemente conocida ni usada en nuestro medio. Se revisa la clasificación actual y la correlación con imágenes de aquellas anomalías vasculares situadas en partes blandas, dada la importancia que tiene un correcto diagnóstico para la terapéutica y pronóstico de los pacientes con estas lesiones.


Asunto(s)
Humanos , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Malformaciones Vasculares/diagnóstico por imagen , Hemangioma/diagnóstico por imagen , Tejido Conectivo/irrigación sanguínea , Malformaciones Vasculares/clasificación , Malformaciones Vasculares/patología , Hemangioma/patología , Neoplasias de Tejido Conjuntivo/patología
11.
Rev. chil. radiol ; 13(4): 185-190, 2007. ilus, tab
Artículo en Español | LILACS | ID: lil-512399

RESUMEN

Introduction: A chondroblastoma is a rare, usually benign, tumor of bone that accounts for approximately 1 percent of all bone tumors, which mainly affects the growing skeleton. Local pain is the most common presenting symptom, and for some patients it implies functional involvement due to its periarticular site. Chondroblastoma most commonly affects the epiphysis of long bones, specially occuring on the lower extremities. Usually, radiography is the first diagnostic imaging technique to be performed and its relatively characteristic findings may cause alarm or lead to misdiagnosis. Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) are complementary studies that best show the lesion, its extension, and soft tissue involvement. Objectives: To present the most frequent manifestations of chondroblastoma in radiographies, establishing the anatomoradiological correlation of lesions. Material and Methods: Thirty-six patients with histologically proven chondroblastoma, who were registered in the National Register of Bone Tumors, between 1959 and 2004, were retrospectively investigated under clinical and radiological viewpoints. Results: Thirty-six patients (26 male, 10 female) whose ages ranged from 5 to 19 years (mean age 14.5 years) were studied. In all cases, biopsy results confirmed the diagnosis of chondroblastoma. Bone lesions were sited as follows: long bones of lower extremities in 22 patients; long bones of upper extremities, 8 cases; feet bones, 3 patients; pelvis, 3 cases, and rib cage in 1 case. Lesions, which were unique in all cases and involved epiphyseal region, were predominantly osteolytic in 30 patients. Metaphyseal extension was found in 28 patients. Eccentric bone lesions were seen in 27 cases, while calcifications were present in 18 patients and 9 cases were found to have soft tissue extensions. Conclusions: Benign epiphyseal chondroblastoma is an unusual bone lesion occuring in young patients, with well-characterized and constant...


Introducción: El condroblastoma es una lesión ósea benigna poco frecuente (1 por ciento - 4.7 por ciento de los tumores óseos primarios), que afecta principalmente al esqueleto en crecimiento. Se manifiesta por dolor local de larga evolución y en algunos pacientes, compromiso funcional por su localización periarticular. Tiene predilección por las epífisis de los huesos largos o su equivalente epifisiarío, especialmente en extremidades inferiores. La radiografía simple es generalmente el primer examen y los hallazgos son relativamente característicos, pudiendo alarmar e inducir a error. Tomografía computada (TC) y resonancia magnética (RM) son complementarias y muestran mejor la lesión, extensión dentro del hueso y compromiso de partes blandas. Objetivos: Mostrarlas manifestaciones más frecuentes del condroblastoma en radiografías, estableciendo correlación anátomo-radiológica de las lesiones. Material y Métodos. Se analizaron retrospectivamente las características clínicas y radiológicas de 36 pacientes con condroblastoma confirmado por histología, incluidos en Registro Nacional de Tumores Óseos (RENATO), entre los años 1959 y 2004. Resultados. Se estudiaron 36 pacientes, 26 varones y 10 niñas, de 5 a 19 años (promedio = 14.5 años). Biopsia compatible con condroblastoma en todos los pacientes y su localización: huesos largos de extremidades inferiores(22), huesos largos de extremidades superiores(8), huesos del pie(3), pelvis(3) y parrilla costal(1). Las lesiones fueron únicas en todos los casos, predominantemente osteolíticas(30). La totalidad comprometía la epífisis; se observó extensión hacia la metáfisis(28), lesión ósea excéntrica(27), calcificaciones(W) y extensión hacia partes blandas(9). Conclusión. El condroblastoma epifisiario benigno es una lesión poco frecuente, de pacientes jóvenes, con manifestaciones radiológicas relativamente constantes y características, lo que puede permitir al radiólogo sospechar el diagnóstico en la radiografía simple ini...


Asunto(s)
Humanos , Masculino , Femenino , Niño , Adolescente , Condroblastoma/patología , Condroblastoma , Neoplasias Óseas/patología , Neoplasias Óseas , Estudios Retrospectivos
12.
Rev. chil. dermatol ; 26(2): 122-130, 2010. tab, ilus
Artículo en Español | LILACS | ID: lil-569956

RESUMEN

Las anomalías vasculares de las partes blandas superficiales son frecuentes en el niño y se han clasificado en hemangiomas y malformaciones vasculares, según sus manifestaciones clínicas y hallazgos histológicos. La mayoría corresponde a hemangiomas, se presenta en el recién nacido, desaparece espontáneamente con el tiempo y sólo algunos de ellos requerirán de evaluación médica. Es importante especificar el tipo de lesión vascular para definir el tratamiento, lo que en la mayor parte de los casos es posible con los hallazgos clínicos. Sin embargo, a veces es necesario recurrir a estudios de imágenes para precisar el diagnóstico y los métodos más utilizados son la Ultrasonografía (US) Doppler-color; Resonancia magnética (RM) y Angiografía. La US Doppler-color es un método sencillo, inocuo, no invasivo, que permite diferenciar las lesiones superficiales de aquellas profundas y además permite evaluar la vascularización de la lesión y, de esta manera, lograr una adecuada aproximación diagnóstica. También permite seleccionar aquellos casos que requerirán de métodos más sofisticados, como RM o angiografía. El objetivo de esta revisión es mostrar la utilidad de la US Doppler en el estudio de las anomalías vasculares de las partes blandas superficiales en el niño.


Vascular anomalies of superficial soft tissues are frequent in children and have been classified in hemangiomas and vascular malformations, depending on clinical and histological findings. Most correspond to hemangiomas, present in the newborn period, which disappear spontaneously with time and only some may require an imaging evaluation. It is important to specify the type of vascular anomaly in order to define management, which in most cases is possible with just clinical findings. Nevertheless, some cases may require imaging studies to define diagnosis, and the most utilized methods are Doppler ultrasonography (US), magnetic resonance Imaging (MRI) and angiography. Doppler US is a non invasive, harmless and simple method which allows to differentiate between deep and superficial lesions. It also permits to evaluate vascularization and in this manner; achieve an adequate diagnosis and select those cases that will require more sophisticated methods like MRI or angiography. The main objective of this review is to show the role of Doppler US in the study of superficial soft tissue vascular anomalies in children.


Asunto(s)
Humanos , Niño , Malformaciones Vasculares , Ultrasonografía Doppler en Color , Capilares/anomalías , Fístula Arteriovenosa , Hemangioma , Malformaciones Arteriovenosas , Malformaciones Vasculares/clasificación , Neoplasias de los Tejidos Blandos , Sistema Linfático/anomalías , Sistema Linfático/irrigación sanguínea , Venas/anomalías
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