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1.
J Invest Dermatol ; 82(2): 156-60, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6693779

RESUMEN

Human skin is composed of several layers which are characterized by a specific macromolecular organization of connective tissue. Three approaches were used to quantify the collagen types present in each of the different layers: biochemical analysis of authentic tissue, metabolic labeling of organ cultures, and metabolic labeling of fibroblast monolayers. We obtained reproducible evidence for a somewhat higher ratio of type III/type I collagen synthesis in the papillary dermis and the subcutaneous fat compared to the reticular layer. Constant amounts of alpha 1 (I) trimers and type V collagen were found in all layers. The degree of hydroxylation of lysine in either type I or type III collagen was the same in any layer of the skin.


Asunto(s)
Colágeno/metabolismo , Tejido Conectivo/metabolismo , Piel/metabolismo , Tejido Adiposo/metabolismo , Adulto , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Hidroxilación , Sustancias Macromoleculares , Técnicas de Cultivo de Órganos , Distribución Tisular
2.
J Invest Dermatol ; 87(2): 217-20, 1986 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3525687

RESUMEN

Fibroblast cultures are widely used to study abnormalities of collagen metabolism in both inborn and acquired diseases. However, there is reason to question the extent to which the experimental information obtained from in vitro culture systems in fact reflects the in vivo situation. In the present study we analyzed the proportions of collagens I and III synthesized by human and mouse skin fibroblasts maintained under various culture conditions. The amount of type III collagen extracted from skin specimens was lower than that which was newly synthesized in organ culture. Cells obtained by enzymatic disintegration of skin specimens synthesized more type III collagen than fibroblasts grown from explants. However, subcultivation of the enzymatically liberated cells resulted in a continuous decline of type III collagen production which eventually reached levels similar to those observed in explant cultures.


Asunto(s)
Colágeno/biosíntesis , Animales , Células Cultivadas , Colágeno/clasificación , Electroforesis Discontinua , Embrión de Mamíferos , Fibroblastos/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Ratones , Técnicas de Cultivo de Órganos , Piel/metabolismo
3.
AJNR Am J Neuroradiol ; 21(8): 1486-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11003284

RESUMEN

We report a case of a hypothalamic chiasmatic ganglioglioma in a 21-year-old woman who presented with hyperprolactinemia and developed visual field defects. This circumscribed cystic lesion with an enhancing mural nodule was radiologically indistinguishable from a pilocytic astrocytoma. Although rare, gangliogliomas should be included in the differential diagnosis of lesions occurring in this area of the brain.


Asunto(s)
Ganglioglioma/diagnóstico , Quiasma Óptico , Neoplasias del Nervio Óptico/diagnóstico , Adulto , Femenino , Humanos , Hipotálamo/patología , Quiasma Óptico/patología
4.
AJNR Am J Neuroradiol ; 20(2): 249-55, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10094346

RESUMEN

BACKGROUND AND PURPOSE: Our objective was to compare the reliability of CT venography with intraarterial digital subtraction angiography (DSA) in imaging cerebral venous anatomy and pathology. METHODS: In 25 consecutive patients, 426 venous structures were determined as present, partially present, or absent by three observers evaluating CT multiplanar reformatted (MPR) and maximum intensity projection (MIP) images. These results were compared with the results from intraarterial DSA and, in a second step, with the results of an intraobserver consensus. In addition, pathologic conditions were described. RESULTS: Using DSA as the standard of reference, MPR images had an overall sensitivity of 95% (specificity, 19%) and MIP images a sensitivity of 80% (specificity, 44%) in depicting the cerebral venous anatomy. On the basis of an intraobserver consensus including DSA, MPR, and MIP images (415 vessels present), the sensitivity/specificity was 95%/91% for MPR, 90%/100% for DSA, and 79%/91% for MIP images. MPR images were superior to DSA images in showing the cavernous sinus, the inferior sagittal sinus, and the basal vein of Rosenthal. Venous occlusive diseases were correctly recognized on both MPR and MIP images. Only DSA images provided reliable information of invasion of a sinus by an adjacent meningioma. CONCLUSION: CT venography proved to be a reliable method to depict the cerebral venous structures. MPR images were superior to MIP images.


Asunto(s)
Angiografía de Substracción Digital , Angiografía Cerebral , Venas Cerebrales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Trastornos Cerebrovasculares/diagnóstico por imagen , Medios de Contraste/administración & dosificación , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inyecciones Intraarteriales , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Dosis de Radiación , Sensibilidad y Especificidad
5.
AJNR Am J Neuroradiol ; 17(8): 1495-9, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8883648

RESUMEN

PURPOSE: To evaluate the reliability of source images and maximum intensity projection images of MR angiography in showing the arterial segments of the circle of Willis. METHODS: In 62 patients, 526 arterial segments of the circle of Willis were determined to be present, partially present, or absent by blinded observers evaluating MR angiographic source images and maximum intensity projection images. Vessel diameter was measured on source images. These results were then compared with the results from intraarterial digital subtraction angiography. RESULTS: MR angiographic maximum intensity projection images had a sensitivity of 87% and a specificity of 88% and MR angiographic source images had a sensitivity of 89% and a specificity of 63% in depicting the presence of a vessel segment. The positive predictive value of an arterial segment with a diameter of at least 1 mm was 99%. CONCLUSION: MR angiography is a sensitive technique for detecting the anatomy of the circle of Willis. Maximum intensity projection images are more specific than source images. An arterial segment with a diameter of at least 1 mm on the source image is almost always present and patent.


Asunto(s)
Angiografía de Substracción Digital , Círculo Arterial Cerebral/patología , Angiografía por Resonancia Magnética , Adolescente , Adulto , Anciano , Arteriopatías Oclusivas/diagnóstico , Arteriopatías Oclusivas/diagnóstico por imagen , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/diagnóstico por imagen , Círculo Arterial Cerebral/diagnóstico por imagen , Femenino , Humanos , Aumento de la Imagen , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Intensificación de Imagen Radiográfica , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego
6.
Neurosurgery ; 42(1): 166-70; discussion 170-1, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9442519

RESUMEN

OBJECTIVE AND IMPORTANCE: The posterior pituitary lobe is rarely the site of symptomatic primary tumors. The most common lesions arising from the neurohypophysis and the pituitary stalk seem to be granular cell tumors (GCTs), of which only 42 symptomatic cases have been reported. Here we present an unusually well-documented case of a GCT, which has implications for the differential diagnosis of sellar masses. CLINICAL PRESENTATION: A 75-year-old woman presented with decreased visual acuity, visual field loss, and a 2-year history of progressive vertigo and headaches. Neuroradiological studies showed a supra- and intrasellar, 25 x 20-mm mass, containing calcifications, that compressed the optic chiasm and extended into the third ventricle. INTERVENTION: The tumor was subtotally resected through a transsphenoidal approach. The tumor was tough and vascular and could not be suctioned. Histological examination revealed a typical GCT. The postoperative course was uneventful. Residual tumor was treated with fractionated radiation therapy. Ophthalmological testing 10 months after surgery showed a slight improvement in the visual symptoms. CONCLUSION: Tumor calcifications in computed tomographic scans do not exclude a GCT. The diagnosis requires histological confirmation. Surgical removal by the transsphenoidal approach is the therapy of choice, as for other sellar tumors. Radiation therapy may be advisable after subtotal resection. Our literature review suggests the possibility of gender-related tumor biology in GCTs.


Asunto(s)
Tumor de Células Granulares/diagnóstico , Neoplasias Hipofisarias/diagnóstico , Anciano , Calcinosis/diagnóstico , Calcinosis/patología , Diagnóstico Diferencial , Femenino , Tumor de Células Granulares/patología , Tumor de Células Granulares/cirugía , Humanos , Imagen por Resonancia Magnética , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/cirugía , Tomografía Computarizada por Rayos X
7.
Swiss Med Wkly ; 131(39-40): 582-7, 2001 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-11775493

RESUMEN

PRINCIPLES: Intramedullary spinal cord tumours are rare. The long-term results depend on their varying natural histories and the surgical approach. Less extensive tumour resection avoids greater postoperative neurological impairment without a negative impact on postoperative outcome. METHODS: Twenty-seven patients who underwent a total of 34 surgical interventions (including 7 reoperations) were clinically and radiologically reinvestigated. Histology revealed 19 glial, 4 nonglial and 4 miscellaneous tumours. RESULTS: Postoperative long-term clinical follow-up (mean 62 months postoperatively) in 25 patients revealed functional improvement in 2 cases, stable conditions in 17 and deterioration in 6. Although there was residual tumour on MRI in 19 of the 22 patients reexamined, stable radiological studies were seen in 15 cases. Despite the high percentage of partial resections or biopsies, good long-term clinical results were found in 19 patients (70%). CONCLUSION: The long-term outcome depends on tumour biology and the type of surgery. For low-grade astrocytomas we propose partial resection without incurring the risk of major postoperative neurological deficits, with semi-annual and, after 5 years, annual follow-up. Despite the fact that ependymomas are amenable to complete surgical resection, this was achieved in only one of six cases in this series. Postoperative MRI follow-up of intramedullary tumours must be protracted, as most of these tumours are slow-growing. An increase in the extent and intensity of contrast enhancement of the tumours was defined as tumour recurrence or progressive tumour growth.


Asunto(s)
Astrocitoma/patología , Neoplasias de la Médula Espinal/patología , Adulto , Astrocitoma/diagnóstico por imagen , Astrocitoma/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Radiografía , Neoplasias de la Médula Espinal/diagnóstico por imagen , Neoplasias de la Médula Espinal/cirugía , Resultado del Tratamiento
8.
Rofo ; 161(5): 404-11, 1994 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-7948994

RESUMEN

Chest radiographs and CT images of 25 patients with pleural empyemas were compared retrospectively with those of 20 patients with pleural exudates and transudates in order to determine criteria for differential diagnosis and to define the place of CT in the diagnosis of pleural empyemas. The sign which was most suggestive of an empyema on a chest radiograph was an encapsulated effusion in an atypical position (18/25); this was found in only 4 out of 20 exudates and in none of the transudates. On CT, changes in the pleura, the subcostal tissues and the configuration and position of the fluid were suggestive of an empyema. In nearly all patients with a pleural empyema there was thickening and increased contrast uptake of the parietal pleura (22/25) and thickening and increased density oft the subcostal tissues (23/25). Usually, empyemas were encapsulated and biconvex (20/25). None of the patients with pleural transudates showed any of these changes. In the presence of some pleural exudates, pleural (14/20) or thoracic (11/20) changes were noted. In part, these changes were due to previous treatment (sclerotherapy) or tumour infiltration (7/20). An attempt to correlate the CT findings with changes in the pleura and subcostal tissues with the clinical empyema stages I-III, according to Light, showed that CT was unable to distinguish between early and late empyemas. Consequently, diagnostic aspiration remains necessary for correct treatment.


Asunto(s)
Empiema Pleural/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Infecciones por Bacterias Gramnegativas/diagnóstico por imagen , Infecciones por Bacterias Grampositivas/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Derrame Pleural/diagnóstico por imagen , Radiografía Torácica , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/instrumentación , Tomografía Computarizada por Rayos X/métodos
9.
Rofo ; 162(4): 274-81, 1995 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-7749081

RESUMEN

AIM: The blood distribution on CCT and the prognosis of patients with nonaneurysmal subarachnoidal haemorrhage were retrospectively studied and compared to a patient group with aneurysmal haemorrhage. METHODS: The blood distribution on CCT (72 h after bleeding episode) of 26 patients with nonaneurysmal subarachnoidal haemorrhage confirmed by two normal cerebral angiograms was compared to the blood distribution of 76 patients with aneurysmal haemorrhage. The clinical condition of these patients was further analysed, 4-60 months after the bleeding episode. RESULTS: In 62% of patients with nonaneurysmal haemorrhage the blood distribution was perimesencephalic. The aneurysmal blood distribution pattern was more extended and only one patient showed a perimesencephalic pattern. 80% of the patients without aneurysms in angiography had no limitations in daily functional capacity. CONCLUSION: The perimesencephalic pattern is frequently found in patients with nonaneurysmal subarachnoidal haemorrhage, the prognosis of these patients is excellent. Rarely is the perimesencephalic haemorrhage caused by a ruptured aneurysm. It needs thorough angiographic evaluation.


Asunto(s)
Hemorragia Subaracnoidea/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Quistes Aracnoideos/complicaciones , Angiografía Cerebral , Femenino , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/etiología
10.
J Vet Intern Med ; 28(2): 305-10, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24495193

RESUMEN

BACKGROUND: Serum and urine Blastomyces antigen concentrations can be used to diagnose blastomycosis in dogs. OBJECTIVES: Blastomyces antigen concentrations correlate with clinical remission in dogs during antifungal treatment, and detect disease relapse after treatment discontinuation. ANIMALS: 21 dogs with newly diagnosed blastomycosis monitored until clinical remission (Treatment Phase), and 27 dogs monitored over 1 year from the time of antifungal discontinuation or until clinical relapse (After Treatment Phase). METHODS: Prospective study. Dogs were monitored monthly during treatment and every 3 months after treatment discontinuation, with a complete history, physical exam, chest radiographs, and ocular exam. Urine and serum Blastomyces antigen concentrations were measured at each visit using a quantitative enzyme immunoassay. RESULTS: At enrollment in the Treatment Phase, Blastomyces antigen was positive in all 21 urine samples (100% sensitivity; 95% CI 85-100%), and in 18 of 20 serum samples (90% sensitivity; 95% CI 70-97%). At 2-4 months of treatment, urine antigen was more sensitive for clinically detectable disease (82%; CI 60-94%) than serum antigen (18%; CI 6-41%). The sensitivity of the urine test for clinical relapse was 71% (CI 36-92%), with close to 100% specificity (CI 84-100%) during after treatment surveillance in this population. CONCLUSIONS: Urine Blastomyces antigen testing has high sensitivity for active disease at the time of diagnosis and during treatment, and moderate sensitivity but high specificity for clinical relapse. Urine testing should be useful at the time of diagnosis, when treatment discontinuation is being considered, and anytime there is poor clinical response or suspicion of relapse.


Asunto(s)
Antígenos Fúngicos/sangre , Blastomyces/inmunología , Blastomicosis/veterinaria , Enfermedades de los Perros/inmunología , Animales , Antifúngicos/uso terapéutico , Antígenos Fúngicos/orina , Blastomicosis/diagnóstico , Blastomicosis/tratamiento farmacológico , Blastomicosis/inmunología , Blastomicosis/microbiología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/tratamiento farmacológico , Perros , Masculino , Recurrencia , Inducción de Remisión
11.
J Vet Intern Med ; 26(4): 911-9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22519720

RESUMEN

BACKGROUND: Diagnosis of canine systemic aspergillosis requires fungal culture from a sterile site, or confirmatory histopathology from a nonsterile site. Invasive specimen collection techniques may be necessary. OBJECTIVE: To evaluate the sensitivity and specificity of a serum and urine Aspergillus galactomannan antigen (GMA) ELISA assay for diagnosis of systemic aspergillosis in dogs. DESIGN: Multicenter study. ANIMALS: Thirteen dogs with systemic aspergillosis and 89 dogs with other diseases. Thirty-seven of the 89 dogs had signs that resembled those of systemic aspergillosis and 52 dogs were not suspected to have aspergillosis. PROCEDURE: The GMA ELISA was performed on serum specimens from all dogs and urine specimens from 67 dogs. Galactomannan indices (GMI) ≥ 0.5 were considered positive. Results for dogs in each group were compared. RESULTS AND CONCLUSIONS: The sensitivity and specificity of the assay for serum were 92 and 86%, respectively, and for urine were 88 and 92%, respectively. False negatives were seen only in dogs with localized pulmonary aspergillosis. Use of a cutoff GMI of 1.5 increased specificity to 93% for both serum and urine without loss of sensitivity for diagnosis of disseminated infection. High-level false positives (> 1.5) occurred in dogs with other systemic mycoses and those treated with Plasmalyte. CLINICAL RELEVANCE: Serum and urine Aspergillus GMA ELISA is a noninvasive, sensitive, and specific test for the diagnosis of disseminated aspergillosis in dogs when a cutoff GMI of ≥ 1.5 is used.


Asunto(s)
Aspergilosis/veterinaria , Aspergillus/aislamiento & purificación , Enfermedades de los Perros/microbiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Mananos/análisis , Animales , Aspergilosis/sangre , Aspergilosis/orina , Estudios de Casos y Controles , Enfermedades de los Perros/sangre , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/orina , Perros , Ensayo de Inmunoadsorción Enzimática/métodos , Reacciones Falso Positivas , Femenino , Galactosa/análogos & derivados , Masculino , Mananos/sangre , Mananos/orina , Estudios Retrospectivos , Sensibilidad y Especificidad , Estadísticas no Paramétricas
12.
AJNR Am J Neuroradiol ; 31(9): 1651-2, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20019101

RESUMEN

Early diagnosis and prompt initiation of adequate treatment are essential for clinical outcome in ISCA. We report a case in which DWI provided a more specific diagnosis than conventional MR imaging and allowed differentiation of a ring-enhancing lesion from intramedullary tumor. Diagnosis was proved by PCR from CSF (Streptococcus intermedius). Adequate antibiotic treatment was immediately initiated, and the patient recovered completely.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Absceso Epidural/patología , Médula Espinal/patología , Anciano de 80 o más Años , Femenino , Humanos
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