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1.
Med Biol Eng Comput ; 42(3): 366-77, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15191083

RESUMEN

Neuroblastoma is the most common extra-cranial, solid, malignant tumour in children. Advances in radiology have made possible the detection and staging of the disease. Nevertheless, there is no method available at present that can go beyond detection and qualitative analysis, towards quantitative assessment of the tissue composition of the primary tumour mass in neuroblastoma. Such quantitative analysis could provide important information and serve as a decision-support tool to the radiologist and the oncologist, result in better treatment and follow-up and even lead to the avoidance of delayed surgery. The problem investigated was the improvement of the analysis of the primary tumour mass, in patients with neuroblastoma, using X-ray computed tomography (CT) images. A methodology was proposed for the estimation of the tissue content of the mass: it comprised a Gaussian mixture model for estimation, from segmented CT images, of the tissue composition of the primary tumour. To demonstrate the potential of the method, the results are presented of its application to ten CT examinations of four patients. The method provides quantitative information, and it was observed that the tumour in one of the patients reduced from 523 cm3 to 81 cm3 in volume, with an increase in calcification from about 20% to about 88% of the tumour volume, in response to chemotherapy over a period of five months. Results indicate that the proposed technique may be of considerable value in assessing the response to therapy of patients with neuroblastoma.


Asunto(s)
Neuroblastoma/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Niño , Preescolar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Modelos Biológicos , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Resultado del Tratamiento
3.
J Pediatr Surg ; 35(5): 771-4, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10813347

RESUMEN

Although relatively common in adults, leiomyoma of the esophagus is a rare disorder in children. A single case report describes the coexistence of both esophageal and bronchial leiomyoma in a child. The authors describe the diagnostic and treatment challenges encountered in a 2-year-old boy with coexisting inflammatory pseudotumor and esophageal leiomyoma presenting as massive atelectasis.


Asunto(s)
Obstrucción de las Vías Aéreas/etiología , Enfermedades Bronquiales/diagnóstico , Neoplasias Esofágicas/diagnóstico , Granuloma de Células Plasmáticas/diagnóstico , Leiomioma/diagnóstico , Obstrucción de las Vías Aéreas/diagnóstico , Biopsia con Aguja , Enfermedades Bronquiales/complicaciones , Enfermedades Bronquiales/cirugía , Preescolar , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/cirugía , Estudios de Seguimiento , Granuloma de Células Plasmáticas/complicaciones , Granuloma de Células Plasmáticas/cirugía , Humanos , Leiomioma/complicaciones , Leiomioma/cirugía , Masculino , Tomografía Computarizada por Rayos X
4.
Pathology ; 29(3): 251-4, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9271009

RESUMEN

Epidermal growth factor receptor (EGFR) is a transmembrane protein receptor with tyrosine kinase activity. The protein has cysteine-rich sequence repeats in its extracellular ligand-binding domains. Elevated levels of EGFR are associated with malignant transformation of squamous cells and are observed in squamous cell carcinomas from the lung, head, neck, skin, cervix and esophagus. We examined the expression of EGFR in laryngeal squamous cell carcinoma (SCC) (N = 24) and non-neoplastic polyps (N = 7) using streptavidin-biotin immunohistochemistry and a monoclonal antibody (Serotec: MCA-571) to the EGFR protein. The carcinomas were classified as well differentiated (N = 2), moderately differentiated (N = 16) and poorly differentiated (N = 6). Tissues from metastatic tumor deposits in lymph nodes (N = 5) were also studied. Overexpression of EGFR was present, in the form of strong cytoplasmic immunostaining, in the majority of the SCC cases (n = 20; 83%) and in all of the metastatic tumor deposits. In contrast, although some of the vocal cord polyps showed weak (n = 2) to moderate (n = 5) immunoreactivity, none had evidence of strong EGFR immunoreactivity. The differences in EGFR immunoreactivity were significant between primary laryngeal SCC and vocal cord polyps (p = 0.0001; chi 2 test), and between metastatic laryngeal SCC and vocal cord polyps (p = 0.0001; chi 2 test). Laryngeal carcinoma cases which showed EGFR overexpression had a lower median survival period compared to those without overexpression In conclusion, a different extent of EGFR expression is demonstrated in laryngeal squamous cell carcinomas and non-neoplastic vocal cord polyps using an immunohistochemical method. Some trends in the prognostic value of EGFR immunoreactivity in laryngeal carcinomas appear to emerge in this study.


Asunto(s)
Carcinoma de Células Escamosas/química , Receptores ErbB/análisis , Neoplasias Laríngeas/química , Pólipos/química , Pliegues Vocales , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fijadores , Formaldehído , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Adhesión en Parafina
5.
Aust N Z J Surg ; 66(7): 464-8, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8678876

RESUMEN

BACKGROUND: Transforming growth factor alpha (TGF-alpha) is a polypeptide that is structurally similar to epidermal growth factor (EGF) that binds to the epidermal growth factor receptor (EGFR) and has been implicated in the development of several types of human tumours. METHODS: The expression of TGF-alpha is examined in laryngeal squamous cell carcinoma (SCC) (n = 24) and non-neoplastic polyps (n = 7) using streptavidin-biotin immunohistochemistry and a monoclonal antibody to the TGF-alpha protein. These cases had been previously characterized for EGFR immunoreactivity. The carcinomas were classified as well differentiated (n = 2), moderately differentiated (n = 16) and poorly differentiated (n = 6). Tissues from metastatic tumour deposits in lymph nodes (n = 5) were also studied. RESULTS: TGF-alpha overexpression was defined as intense immunoreactivity in more than two-thirds of tumour cells immunostained for TGF-alpha and was present in the majority of the SCC cases (n = 15; 63%) and metastatic tumour deposits (n = 4; 80%). In contrast, although some of the vocal cord polyps showed weak (n = 2) to moderate (n = 5) immunostaining, none had evidence of strong TGF-alpha immunoreactivity. The differences in TGF-alpha immunoreactivity were significant between primary laryngeal SCC and vocal cord polyps (P = 0.013; chi 2 test with continuity correction), and between metastatic laryngeal SCC and vocal cord polyps (P = 0.023; chi 2 test with continuity correction). There was no significant difference in TGF-alpha expression between the different grades of carcinomas (P = 0.92, chi 2 test) or between non-metastatic and metastatic carcinomas (P = 0.82; chi 2 test with continuity correction). No significant correlation was found between TGF-alpha expression and patient survival or tumour recurrence (r = 0.077, r2 = 0.006, P = 0.75; simple regression analysis), or between TGF-alpha expression and EGFR immunoreactivity (r = 0.325, r2 = 0.106, P = 0.0851). CONCLUSIONS: In conclusion, increased TGF-alpha immunoreactivity is present in most cases of laryngeal SCC with no specific relationship to tumour grade, suggesting that it may be important in the development of laryngeal carcinomas but not in its progression. No significant correlation was found between TGF-alpha and EGFR expression in laryngeal tumours and TGF-alpha immunoreactivity is of no prognostic value.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Receptores ErbB/metabolismo , Neoplasias Laríngeas/metabolismo , Factor de Crecimiento Transformador alfa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Pólipos/metabolismo , Pronóstico , Análisis de Regresión , Pliegues Vocales/metabolismo
6.
Cancer ; 77(11): 2246-50, 1996 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-8635091

RESUMEN

BACKGROUND: The nm23-H1 gene encodes a 17-kilodalton cytoplasmic and nuclear protein that has recently been shown to be reduced in a number of human carcinomas including breast, colorectal, lung, gallbladder, and biliary tract carcinomas. This study examines the immunohistochemical staining characteristics of the nm23-H1 protein in human laryngeal carcinomas and nonneoplastic laryngeal polyps, and attempts to determine if there is any relationship between reduction of nm23-H1 protein immunoreactivity and prognosis of patients with laryngeal carcinoma. METHODS: Routine streptavidin-biotin immunohistochemistry with a polyclonal antibody was employed to study the expression of the nm23-H1 protein in laryngeal squamous cell carcinoma (SCC) (N = 22) and nonneoplastic polyps (N = 8). The carcinomas were classified as well differentiated (N = 2), moderately differentiated (N =15), and poorly differentiated (N = 5). Tissues from metastatic tumor deposits in lymph nodes (N = 5) were also studied. A semiquantitative immunostaining index was derived from the intensity and extent of staining of the cells. RESULTS: All laryngeal polyps showed intense immunostaining for the nm23-H1 gene product in the squamous epithelium. However, reduced immunoreactivity was found in nearly half of the SCC cases (N = 10; 46%), with the least staining intensity found in tumor metastases in lymph nodes (N = 4; 80%), and were associated with a shorter median survival of 14.3 months. In contrast, tumors that demonstrated moderate to strong nm23-H1 protein immunostaining were associated with a longer median survival period of 20.4 months. CONCLUSIONS: There is reduced expression of the nm23-H1 gene in human laryngeal SCC compared with nonneoplastic laryngeal polyps. Reduction in the intensity and extent of nm23-H1 protein immunostaining appears to correspond to reduced duration of patients survival.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/química , Neoplasias Laríngeas/química , Proteínas de Unión al GTP Monoméricas , Proteínas de Neoplasias/análisis , Nucleósido-Difosfato Quinasa , Factores de Transcripción/análisis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Diferenciación Celular , Progresión de la Enfermedad , Femenino , Humanos , Neoplasias Laríngeas/mortalidad , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad , Nucleósido Difosfato Quinasas NM23 , Pólipos/química , Pólipos/mortalidad , Pronóstico , Análisis de Supervivencia , Pliegues Vocales
7.
Pathology ; 28(2): 135-8, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8743818

RESUMEN

Abnormal patterns of expression of the basement membrane type IV collagen are observed in many human cancers. This study examines the immunohistological expression of type IV collagen in the basement membrane in human laryngeal squamous cell carcinomas (SCC) (n = 24). Non-neoplastic vocal cord polyps (n = 4) were used as controls. The formalin-fixed, paraffin-embedded tissues were sectioned and pretreated with protease prior to immunostaining for type IV collagen. There was a statistically significant difference in type IV collagen expression between laryngeal SCC and vocal cord polyps (p = 0.0001; chi 2 test with continuity correction). In laryngeal SCC (n = 24; 100%), type IV collagen distribution was discontinuous and irregular or absent around individual or groups of neoplastic cells. In contrast, all of the cases of vocal cord polyps (n = 4; 100%) displayed a continuous pattern of subepithelial basement membrane type IV collagen. This study has shown that abnormal distribution of type IV collagen occurs in laryngeal squamous cell carcinomas but not in non-neoplastic vocal cord polyps. This may be related to either abnormal synthesis or to the breakdown of the collagen and it may be of use as a potential biological marker in the study of laryngeal carcinogenesis.


Asunto(s)
Carcinoma/inmunología , Colágeno/inmunología , Neoplasias Laríngeas/inmunología , Anticuerpos Monoclonales/inmunología , Biomarcadores de Tumor , Carcinoma/diagnóstico , Femenino , Humanos , Inmunohistoquímica , Neoplasias Laríngeas/diagnóstico , Masculino
8.
Pathology ; 25(4): 394-7, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8165006

RESUMEN

The expression of the nuclear phosphoprotein, p53, was studied in 21 cases of squamous cell carcinoma of the larynx and 16 benign laryngeal lesions using the polyclonal rabbit antibody, CM1 (Novocastra Laboratories Ltd). Fourteen of the carcinomas showed nuclear staining whereas only one of the benign lesions exhibited presence of the protein. This suggests that, as with squamous cell carcinoma of the lung, p53 plays a role in the development of malignant disease of the larynx.


Asunto(s)
Carcinoma de Células Escamosas/química , Neoplasias Laríngeas/química , Proteína p53 Supresora de Tumor/biosíntesis , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Técnicas para Inmunoenzimas , Enfermedades de la Laringe/metabolismo , Neoplasias Laríngeas/patología , Masculino , Persona de Mediana Edad
9.
Can Fam Physician ; 37: 889-900, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21229068

RESUMEN

The clinical and radiological presentations of 12 pediatric urological disorders are described. The described disorders include pyelonephritis, vesicoureteral reflux, ureteropelvic obstruction, ureterovesical obstruction, ectopic ureterocele, posterior urethral valves, multicystic dysplastic kidney, polycystic kidney disease, ectopic kidney, staghorn calculi, urethral diverticulum, and urethral meatal stenosis.

10.
Dev Med Child Neurol ; 32(10): 882-7, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2257986

RESUMEN

The authors examined the incidence of widened subarachnoid spaces (SAS) among 75 infants with birthweights less than or equal to 1250g, and their significance in developmental outcome. Nine of 30 infants with gestations less than or equal to 27 weeks had widened SAS in their pre-discharge ultrasound scans. Three of the nine, including two with periventricular leukomalacia (PVL), had late-onset ventricular enlargement, unrelated to intraventricular haemorrhage (IVH): all three were developmentally impaired. The other six infants without ventricular enlargement developed normally, including one with IVH. Five of the remaining 21 infants with gestations less than or equal to 27 weeks and without widened SAS were developmentally impaired. Widened SAS was not associated with a significantly increased risk of developmental impairment; ventricular enlargement and PVL were the only significant factors. The authors conclude that an isolated finding of widened SAS is not predictive of impairment in immature infants.


Asunto(s)
Corteza Cerebral/patología , Ecoencefalografía , Enfermedades del Prematuro/diagnóstico , Leucomalacia Periventricular/diagnóstico , Espacio Subaracnoideo/patología , Atrofia , Hemorragia Cerebral/diagnóstico , Estudios de Seguimiento , Humanos , Hidrocefalia/diagnóstico , Recién Nacido de Bajo Peso/fisiología , Recién Nacido , Examen Neurológico
11.
Child Nephrol Urol ; 10(4): 205-10, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2088592

RESUMEN

Genital edema is a recognized complication of continuous ambulatory peritoneal dialysis (CAPD) in adults. Two children who developed genital edema while on CAPD are reported. The edema developed in both children as a consequence of a peritoneal leak in the inguinal region. A computerized tomogram (CT) scan of the abdomen is an excellent method to identify the site of the peritoneal leak. The literature is reviewed and the pathophysiology of the development of genital swelling and edema is discussed.


Asunto(s)
Edema/etiología , Enfermedades del Pene/etiología , Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Escroto , Adolescente , Preescolar , Hernia Inguinal/diagnóstico por imagen , Hernia Inguinal/etiología , Humanos , Fallo Renal Crónico/terapia , Masculino , Tomografía Computarizada por Rayos X
12.
J Ultrasound Med ; 7(3): 125-8, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3280822

RESUMEN

Three cases of regional enteritis (Crohn disease) with secondary involvement of the urinary bladder diagnosed by ultrasound are presented. The ability of ultrasound to simultaneously and noninvasively demonstrate the changes in bladder and adjacent bowel, unlike other radiologic or urologic investigations, is emphasized.


Asunto(s)
Enfermedad de Crohn/complicaciones , Ultrasonografía , Enfermedades de la Vejiga Urinaria/diagnóstico , Absceso/diagnóstico , Absceso/etiología , Adulto , Femenino , Humanos , Masculino , Enfermedades de la Vejiga Urinaria/etiología
13.
Urol Radiol ; 9(4): 220-1, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3394182

RESUMEN

Recognizing the changes of medullary sponge kidney (MSK) on computed tomographic (CT) scans may be of value in both diagnosis and in differentiating this from other disease states. The appearance on CT of MSK has not previously been well described. A case is reported that demonstrates ectatic renal collecting tubules visualized by CT, and techniques are suggested to optimize visualization of these changes.


Asunto(s)
Médula Renal/diagnóstico por imagen , Riñón Esponjoso Medular/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Anciano , Diagnóstico Diferencial , Dilatación Patológica , Femenino , Humanos , Túbulos Renales Colectores/diagnóstico por imagen
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