Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Epilepsy Behav ; 102: 106684, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31778880

RESUMEN

Focal cortical dysplasias (FCDs) are a frequent cause of epilepsy. It has been reported that up to 40% of them cannot be visualized with conventional magnetic resonance imaging (MRI). The main objective of this work was to evaluate by means of a retrospective descriptive observational study whether the automated brain segmentation is useful for detecting FCD. One hundred and fifty-five patients, who underwent surgery between the years 2009 and 2016, were reviewed. Twenty patients with FCD confirmed by histology and a preoperative segmentation study, with ages ranging from 3 to 43 years (14 men), were analyzed. Three expert neuroradiologists visually analyzed conventional and advanced MRI with automated segmentation. They were classified into positive and negative concerning visualization of FCD by consensus. Of the 20 patients evaluated with conventional MRI, 12 were positive for FCD. Of the negative studies for FCD with conventional MRI, 2 (25%) were positive when they were analyzed with automated segmentation. In 13 of the 20 patients (with positive segmentation for FCD), cortical thickening was observed in 5 (38.5%), while pseudothickening was observed in the rest of patients (8, 61.5%) in the anatomical region of the brain corresponding to the dysplasia. This work demonstrated that automated brain segmentation helps to increase detection of FCDs that are unable to be visualized in conventional MRI images.


Asunto(s)
Encéfalo/diagnóstico por imagen , Epilepsia/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Malformaciones del Desarrollo Cortical/diagnóstico por imagen , Adolescente , Adulto , Encéfalo/patología , Encéfalo/cirugía , Niño , Preescolar , Epilepsia/patología , Epilepsia/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Malformaciones del Desarrollo Cortical/patología , Malformaciones del Desarrollo Cortical/cirugía , Estudios Retrospectivos , Adulto Joven
2.
J Bone Miner Res ; 34(10): 1851-1861, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31099911

RESUMEN

Renal transplantation (RTx) is an effective therapy to improve clinical outcomes in pediatric patients with terminal chronic kidney disease. However, chronic immunosuppression with glucocorticoids (GCs) reduces bone growth and BMD. The mechanisms causing GC-induced growth impairment have not been fully clarified. Fibroblast growth factor 23 (FGF23) is a peptide hormone that regulates phosphate homeostasis and bone growth. In pathological conditions, FGF23 excess or abnormal FGF receptors (FGFR) activity leads to bone growth impairment. Experimental data indicate that FGF23 expression is induced by chronic GC exposure. Therefore, we hypothesize that GCs impair bone growth by increasing FGF23 expression, which has direct effects on bone growth plate. In a post hoc analysis of a multicentric randomized clinical trial of prepubertal RTx children treated with early GC withdrawal or chronic GC treatment, we observed that GC withdrawal was associated with improvement in longitudinal growth and BMD, and lower plasma FGF23 levels as compared with a chronic GC group. In prepubertal rats, GC-induced bone growth retardation correlated with increased plasma FGF23 and bone FGF23 expression. Additionally, GC treatment decreased FGFR1 expression whereas it increased FGFR3 expression in mouse tibia explants. The GC-induced bone growth impairment in tibiae explants was prevented by blockade of FGF23 receptors using either a pan-FGFR antagonist (PD173074), a C-terminal FGF23 peptide (FGF23180-205) which blocks the binding of FGF23 to the FGFR-Klotho complex or a specific FGFR3 antagonist (P3). Finally, local administration of PD173074 into the tibia growth plate ameliorated cartilage growth impairment in GC-treated rats. These results show that GC treatment partially reduces longitudinal bone growth via upregulation of FGF23 and FGFR3 expression, thus suggesting that the FGF23/Klotho/FGFR3 axis at the growth plate could be a potential therapeutic target for the management of GC-induced growth impairment in children.


Asunto(s)
Desarrollo Óseo/efectos de los fármacos , Huesos/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Glucocorticoides/administración & dosificación , Trasplante de Riñón , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Densidad Ósea/efectos de los fármacos , Huesos/patología , Niño , Femenino , Factor-23 de Crecimiento de Fibroblastos , Estudios de Seguimiento , Glucocorticoides/efectos adversos , Humanos , Fallo Renal Crónico/metabolismo , Fallo Renal Crónico/patología , Fallo Renal Crónico/cirugía , Proteínas Klotho , Masculino , Proteínas de la Membrana , Ratones , Ratas , Ratas Sprague-Dawley
3.
Gene ; 687: 228-237, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30447344

RESUMEN

The in vitro process of chondrogenic differentiation of mesenchymal stem cells (MSCs) induces a pre-apoptotic hypertrophic phenotype, guided by the active status of the WNT/߭catenin pathway. To achieve a stable chondrocyte phenotype for cartilage tissue engineering, it is necessary to gain a better understanding of specific genes that regulate the cartilage tissue phenotype. RNA sequencing (RNA-seq) analysis of tissue samples from bone, cartilage, growth plate and muscle show that Dickkopf-1 (DKK1), a natural WNT canonical signaling inhibitor, is expressed in cartilage tissue. This observation reinforces the concept that inhibition of the WNT/߭catenin pathway is critical for preventing avoid chondrocyte hypertrophy in vitro. We used two doses of DKK1 in a pellet cell culture system to inhibit the terminal differentiation of chondrocytes derived from bone marrow mesenchymal stem cells (MSCs). Bone marrow MSCs were cultured in chondrogenic induction medium with 50 and 200 ng/ml of DKK1 for 21 days. The highest doses of DKK1 reduce ߭catenin expression and nuclear localization at day 21, concomitant with reduced expression and activity of hypertrophy markers collagen type X (COL10A1) and alkaline phosphatase (ALPL), thus decreasing the pre-hypertrophic chondrocyte population. Furthermore, DKK1 stimulated expression of collagen type II (COL2A1) and glycosaminoglycans (GAGs), which represent healthy articular cartilage markers. We conclude that exogenous DKK1 impedes chondrocyte progression into a prehypertrophic stage and stimulates expression of healthy articular cartilage markers by blocking the WNT/߭catenin pathway. Hence, DKK1 may promote a mature healthy articular cartilage phenotype and facilitate cartilage tissue engineering for joint repair.


Asunto(s)
Biomarcadores/análisis , Células de la Médula Ósea/patología , Condrocitos/patología , Condrogénesis , Hipertrofia/patología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Células Madre Mesenquimatosas/patología , Adulto , Apoptosis , Células de la Médula Ósea/metabolismo , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Condrocitos/metabolismo , Femenino , Humanos , Hipertrofia/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Masculino , Células Madre Mesenquimatosas/metabolismo , Ingeniería de Tejidos , Adulto Joven
4.
J Cell Biochem ; 118(11): 3662-3674, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28370561

RESUMEN

Osteosarcoma is the most common malignant bone tumor in children and adolescents. Metastasis and poor responsiveness to chemotherapy in osteosarcoma correlates with over-expression of the runt-related transcription factor RUNX2, which normally plays a key role in osteogenic lineage commitment, osteoblast differentiation, and bone formation. Furthermore, WNT/ß-catenin signaling is over-activated in osteosarcoma and promotes tumor progression. Importantly, the WNT/ß-catenin pathway normally activates RUNX2 gene expression during osteogenic lineage commitment. Therefore, we examined whether the WNT/ß-catenin pathway controls the tumor-related elevation of RUNX2 expression in osteosarcoma. We analyzed protein levels and nuclear localization of ß-catenin and RUNX2 in a panel of human osteosarcoma cell lines (SAOS, MG63, U2OS, HOS, G292, and 143B). In all six cell lines, ß-catenin and RUNX2 are expressed to different degrees and localized in the nucleus and/or cytoplasm. SAOS cells have the highest levels of RUNX2 protein that is localized in the nucleus, while MG63 cells have the lowest RUNX2 levels which is mostly localized in the cytoplasm. Levels of ß-catenin and RUNX2 protein are enhanced in HOS, G292, and 143B cells after treatment with the GSK3ß inhibitor SB216763. Furthermore, small interfering RNA (siRNA)-mediated depletion of ß-catenin inhibits RUNX2 expression in G292 cells. Thus, WNT/ß-catenin activation is required for RUNX2 expression in at least some osteosarcoma cell types, where RUNX2 is known to promote expression of metastasis related genes. J. Cell. Biochem. 118: 3662-3674, 2017. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Neoplasias Óseas/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/biosíntesis , Proteínas de Neoplasias/biosíntesis , Osteosarcoma/metabolismo , Vía de Señalización Wnt , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Osteosarcoma/genética , Osteosarcoma/patología
5.
Rev. méd. Chile ; 144(12): 1612-1616, dic. 2016. ilus
Artículo en Español | LILACS | ID: biblio-845493

RESUMEN

Benign multicystic peritoneal mesothelioma is an uncommon lesion arising from the peritoneal mesothelium. It is asymptomatic or presents with unspecific symptoms. Imaging techniques may reveal it, however the final diagnosis can only be made by histopathology. Surgery is the only effective treatment considering its high recurrence rate. We report a 19 years old male with Crohn’s disease. Due to persistent abdominal pain, an abdominal magnetic resonance imaging was performed, showing a complex cystic mass in the lower abdomen. The patient underwent surgery and the lesion was completely resected. The pathological study reported a benign multicystic peritoneal mesothelioma.


Asunto(s)
Humanos , Masculino , Adulto Joven , Neoplasias Peritoneales/complicaciones , Enfermedad de Crohn/complicaciones , Mesotelioma Quístico/complicaciones , Neoplasias Peritoneales/cirugía , Neoplasias Peritoneales/patología , Mesotelioma Quístico/cirugía , Mesotelioma Quístico/patología
6.
J Exp Orthop ; 3(1): 20, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27600522

RESUMEN

BACKGROUND: Medial patellofemoral ligament (MPFL) is the main restrictor of lateral shifting of the patella, contributing by 60 % in the first 20° flexion of the knee. MPFL reconstruction has been performed in order to restore the stability of the patella with good results.Lyophilized Gracilis tendon allograft (LGA) compared to Cryopreserved Gracilis tendon allograft (CGA) has a lower cost, does not require to maintain cooling chain or preparation. The purpose of this study is to compare the histological and biomechanical characteristics of an experimental model of reconstruction of the MPFL in porcine patellas with LGA versus CGA. METHODS: Randomized controlled experimental study in porcine model conducted on 36 porcine patellas in which 18 were intervened with LGA and 18 were intervened with CGA. The confluent tunnel technique was used for MPFL reconstruction. Maximum tensile force, allograft elongation and stiffness of the construct were measured. The cellularity and collagen tissue distribution were evaluated in the allografts. The histological and biomechanical characteristics of the LGA were compared to those of the CGA. RESULTS: The median of the maximum tensile force for the LGA group was 299.63 N and 280.86 N for the CGA group (p = 0.45). The median of the stiffness was 57.86 N/mm for the LGA and 54.23 N/mm for the CGA (p = 0.2). The median of the elongation for the LGA was 5.95 mm and 6.12 mm for the CGA (p = 0,29). The bone bridge failed in 88.88 % of the constructs with LGA and 94.44 % in those with CGA (p = 0.5). CONCLUSIONS: No differences were observed between the LGA group and the CGA group in maximum tensile force, elongation, stiffness, site of rupture and histological characteristics. The use of a lyophilized Gracilis tendon allograft for MPFL reconstruction confers the same histological and biomechanical characteristics as a cryopreserved Gracilis tendon allograft.

7.
Rev Med Chil ; 144(12): 1612-1616, 2016 Dec.
Artículo en Español | MEDLINE | ID: mdl-28393997

RESUMEN

Benign multicystic peritoneal mesothelioma is an uncommon lesion arising from the peritoneal mesothelium. It is asymptomatic or presents with unspecific symptoms. Imaging techniques may reveal it, however the final diagnosis can only be made by histopathology. Surgery is the only effective treatment considering its high recurrence rate. We report a 19 years old male with Crohn’s disease. Due to persistent abdominal pain, an abdominal magnetic resonance imaging was performed, showing a complex cystic mass in the lower abdomen. The patient underwent surgery and the lesion was completely resected. The pathological study reported a benign multicystic peritoneal mesothelioma.


Asunto(s)
Enfermedad de Crohn/complicaciones , Mesotelioma Quístico/complicaciones , Neoplasias Peritoneales/complicaciones , Humanos , Masculino , Mesotelioma Quístico/patología , Mesotelioma Quístico/cirugía , Neoplasias Peritoneales/patología , Neoplasias Peritoneales/cirugía , Adulto Joven
8.
Rev Med Chil ; 142(6): 786-90, 2014 Jun.
Artículo en Español | MEDLINE | ID: mdl-25327325

RESUMEN

Sarcomatoid squamous carcinoma (ESC) is a rare esophageal neoplasm, with a clinical, etiological and pathological behavior that differs from squamous cancer. From the histological point of view it has a dual configuration. The squamous epithelial component is usually limited to small areas, while the major part is constituted by mesenchymatous (sarcomatoid) polypoid tissue. Treatment is esophagectomy or total esophagogastrectomy depending on the tumor location. Early detection is critical in terms of survival. For large lesions, preoperative chemo-radiotherapy can be considered. We report a 78-year-old male presenting with dysphagia. An upper gastrointestinal endoscopy showed a tumor located below the cardia. The patient was subjected to a total esophageal and gastric resection. In a second operation, the digestive transit was reconstituted in 2 steps. The pathology report informed a sarcomatoid squamous carcinoma. After 18 months of follow up, the patient is ambulatory.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Anciano , Biopsia , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago , Esofagectomía , Humanos , Masculino , Tomografía Computarizada por Rayos X
9.
Am J Med Genet A ; 164A(9): 2365-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24975390

RESUMEN

Congenital unilateral overgrowth of the upper extremity affecting only the muscle tissue is rare. We describe on the clinical, histopathological, and neuroimaging findings in a 6-year-old girl with a congenital, non-progressive muscle enlargement of the entire left upper limb with an ipsilateral hand deformity. No cutaneous stigmata or additional features were detected. Sanger sequencing for the AKT1, PIK3CA, and PTEN genes identified an activating c.3140A>G, p.H1047R mutation in the PIK3CA gene from the affected muscle DNA. We demonstrate that isolated congenital muscular upper limb overgrowth with aberrant hand muscles is another condition related genetically to the PIK3CA-related overgrowth spectrum.


Asunto(s)
Deformidades Congénitas de la Mano/enzimología , Deformidades Congénitas de la Mano/genética , Músculo Esquelético/anomalías , Mutación/genética , Fosfatidilinositol 3-Quinasas/genética , Secuencia de Bases , Niño , Preescolar , Fosfatidilinositol 3-Quinasa Clase I , Femenino , Deformidades Congénitas de la Mano/diagnóstico por imagen , Humanos , Hipertrofia , Recién Nacido , Imagen por Resonancia Magnética , Datos de Secuencia Molecular , Músculo Esquelético/patología , Radiografía
10.
Rev. méd. Chile ; 142(6): 786-790, jun. 2014. ilus, tab
Artículo en Español | LILACS | ID: lil-722929

RESUMEN

Sarcomatoid squamous carcinoma (ESC) is a rare esophageal neoplasm, with a clinical, etiological and pathological behavior that differs from squamous cancer. From the histological point of view it has a dual configuration. The squamous epithelial component is usually limited to small areas, while the major part is constituted by mesenchymatous (sarcomatoid) polypoid tissue. Treatment is esophagectomy or total esophagogastrectomy depending on the tumor location. Early detection is critical in terms of survival. For large lesions, preoperative chemo-radiotherapy can be considered. We report a 78-year-old male presenting with dysphagia. An upper gastrointestinal endoscopy showed a tumor located below the cardia. The patient was subjected to a total esophageal and gastric resection. In a second operation, the digestive transit was reconstituted in 2 steps. The pathology report informed a sarcomatoid squamous carcinoma. After 18 months of follow up, the patient is ambulatory.


Asunto(s)
Anciano , Humanos , Masculino , Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Biopsia , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Esofagectomía , Tomografía Computarizada por Rayos X
11.
Ann Rheum Dis ; 73(10): 1873-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23894062

RESUMEN

BACKGROUND: Unravelling the basis of joint inflammation and ankylosis represents a major challenge in ankylosing spondylitis (AS) research. As noggin (NOG) and sclerostin (SOST) have recently been associated with the disease process in mouse and human studies, respectively, we explored the immune responses to these two molecules in AS. METHODS: Immune complexes (IC) composed of IgG autoantibodies to NOG and SOST were detected by immunoprecipitation and Western blot analyses. Epitope-specific IgG were measured using peptide-binding ELISA. Serum samples were obtained from healthy controls and patients with AS, mechanical back pain (MBP) and inflammatory bowel disease (IBD) with or without concomitant AS. RESULTS: NOG and SOST-IgG IC were present in NOG-treated and untreated ank/ank (progressive ankylosis), but not in wild-type mice. Higher than normal levels of NOG and SOST-IgG IC are present in AS sera (p<0.001). We showed a SOST peptide (SOST-S146, with homology to a bacterial glycotransferase peptide) binds to a NOG peptide (NOG-N54), which contains a N-glycosylation site. AS patients have higher levels of IgG recognising the NOG-N54 and SOST-S146 peptides compared to the levels in normal controls, IBD and MBP patients (one way analysis of variance p<0.0001). CONCLUSIONS: This is the first report showing IgG autoantibodies to NOG and SOST in normal individuals, and higher levels of NOG and/or SOST-IgG IC probably contribute to neo-ossification in AS patients. These novel findings hold the promise of earlier diagnosis, better management of AS with comorbidities and new therapeutic approaches to modulate ankylosis in AS.


Asunto(s)
Complejo Antígeno-Anticuerpo/sangre , Proteínas Morfogenéticas Óseas/inmunología , Proteínas Portadoras/inmunología , Marcadores Genéticos/inmunología , Espondilitis Anquilosante/inmunología , Proteínas Adaptadoras Transductoras de Señales , Animales , Autoanticuerpos/sangre , Autoantígenos/inmunología , Biomarcadores/sangre , Proteínas Morfogenéticas Óseas/sangre , Proteínas Portadoras/sangre , Estudios de Casos y Controles , Glicoproteínas/sangre , Humanos , Inmunoglobulina G/sangre , Péptidos y Proteínas de Señalización Intercelular , Ratones , Imitación Molecular/inmunología , Espondilitis Anquilosante/diagnóstico
12.
Brain Pathol ; 23(3): 361-2, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23587143

RESUMEN

Benign peripheral nerve sheath tumors are divided into schwannomas, neurofibromas and perineuriomas. In recent years, tumors with hybrid features, composed of multiple, discrete areas of different histological types, were described. These tumors may represent a diagnostic challenge. A 24-year-old woman with multiple sclerosis was found to have a 1.3 cm TV × 0.7 cm AP T2 intermediate lesion within the left internal auditory canal. Gross examination revealed a tan-white, well circumscribed mass. Histologic examination demonstrated a well demarcated, cellular, solid neoplasm with a biphasic pattern. Most of the tumor was composed of spindle cells arranged in fascicles with focal Verocay body formation and diffuse S100 positivity. A second, minor area showed concentric proliferation of neoplastic spindle cells around one or more axons. Tumor cells in this area were positive for perineurial markers, claudin-1 and Glut-1, and focally immunopositive for CD34.We present here a case of a benign peripheral nerve sheath tumor with histological and immunohistochemical features consistent with a dual pattern of differentiation of schwannoma and perineurioma, in the VIIIth cranial nerve. This is, to our knowledge, the first case of a hybrid perineurioma/schwannoma reported in a cranial nerve.


Asunto(s)
Neoplasias del Oído/patología , Oído Interno/patología , Neoplasias de la Vaina del Nervio/patología , Neurilemoma/patología , Neoplasias del Oído/diagnóstico , Neoplasias del Oído/cirugía , Oído Interno/cirugía , Femenino , Humanos , Inmunohistoquímica , Interferón beta/uso terapéutico , Imagen por Resonancia Magnética , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Neoplasias de la Vaina del Nervio/diagnóstico , Neoplasias de la Vaina del Nervio/cirugía , Neurilemoma/diagnóstico , Neurilemoma/cirugía , Procedimientos Neuroquirúrgicos , Resultado del Tratamiento , Adulto Joven
13.
Orthop Clin North Am ; 43(2): 155-71, v, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22480466

RESUMEN

In this article, development of articular cartilage and endochondral ossification is reviewed, from the perspective of both morphologic aspects of histogenesis and molecular biology, particularly with respect to key signaling molecules and extracellular matrix components most active in cartilage development. The current understanding of the roles of transforming growth factor ß and associated signaling molecules, bone morphogenic proteins, and molecules of the Wnt-ß catenin system in chondrogenesis are described. Articular cartilage development is a highly conserved complex biological process that is dynamic and robust in nature, which proceeds well without incident or failure in all joints of most young growing individuals.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Cartílago Articular/metabolismo , Condrogénesis/genética , Factor de Crecimiento Transformador beta/metabolismo , Adulto , Factores de Edad , Biopsia con Aguja , Proteínas Morfogenéticas Óseas/genética , Cartílago Articular/patología , Niño , Preescolar , Condrocitos/metabolismo , Condrogénesis/fisiología , Femenino , Humanos , Inmunohistoquímica , Masculino , Biología Molecular , Transducción de Señal , Factor de Crecimiento Transformador beta/genética
14.
J Rheumatol ; 39(3): 583-93, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22298904

RESUMEN

OBJECTIVE: We assessed the role of Ank in the maintenance of postnatal articular cartilage using the ank/ank mouse (mice homozygous for progressive ankylosis). METHODS: We analyzed ank/ank mice and wild-type littermates (8, 12, and 18 weeks old). Sections from decalcified, paraffin-embedded joints were stained with hematoxylin and eosin. Articular chondrocyte size and cartilage thickness were determined using morphometric methods. Immuno-histochemical staining was performed with anticollagen X, antitissue nonspecific alkaline phosphatase (TNAP), and anti-ß-catenin antibodies on fixed joint sections. Axin2 expression in paw joint lysates in wild-type versus ank/ank mice were compared using Western blot analysis. RESULTS: In all age groups of normal mice studied, calcified cartilage (CC) chondrocyte areas were significantly larger than those of uncalcified cartilage (UC) chondrocytes. However, similar chondrocyte areas (UC vs CC) were found in 12-week and 18-week-old ank/ank mice, indicating that hypertrophic chondrocytes were present in the UC of these mutant mice. The ank/ank mice showed an increase in CC thickness. The ank/ank UC hypertrophic chondrocytes showed diffuse immuno-reactivity for collagen X and TNAP. Increased ß-catenin activation was demonstrated by nuclear localization of ß-catenin staining in ank/ank chondrocytes. Axin2 expression from paw lysates was downregulated in ank/ank mice. CONCLUSION: We identified a previously unrecognized phenotype in the articular cartilage of ank/ank mice: collagen X-positive hypertrophic chondrocytes in the UC. It is possible that consequent to downregulation of axin2 expression, ß-catenin signaling was activated, leading to accelerated chondrocyte maturation and eventual ankylosis in ank/ank joints. Our studies shed new light on the contribution of a key signaling pathway in this model of joint ankylosis.


Asunto(s)
Anquilosis/genética , Anquilosis/metabolismo , Condrocitos/metabolismo , Condrocitos/patología , Fenotipo , Transducción de Señal/fisiología , beta Catenina/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Anquilosis/fisiopatología , Proteína Axina/metabolismo , Cartílago Articular/metabolismo , Cartílago Articular/patología , Colágeno Tipo X/metabolismo , Femenino , Heterocigoto , Hipertrofia , Articulaciones/metabolismo , Articulaciones/patología , Ratones , Ratones Mutantes , Modelos Animales
15.
Arthritis Res Ther ; 13(5): R163, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21992149

RESUMEN

INTRODUCTION: The diagnosis of ankylosing spondylitis is made from a combination of clinical features and the presence of radiographic evidence that may be detected only after many years of inflammatory back pain. It is not uncommon to have a diagnosis confirmed 5 to 10 years after the initial onset of symptoms. Development of a more-sensitive molecular imaging technology to detect structural changes in the joints would lead to earlier diagnosis and quantitative tracking of ankylosis progression. Progressive ankylosis (ank/ank) mice have a loss of function in the Ank gene, which codes for a regulator of PPi transport. In this study, we used these ank/ank mutant mice to assess a noninvasive, quantitative measure of joint ankylosis with near-infrared (NIR) molecular imaging in vivo. METHODS: Three age groups (8, 12, and 18 weeks) of ank/ank (15 mice) and wild-type littermates (12 +/+ mice) were assessed histologically and radiographically. Before imaging, OsteoSense 750 (bisphosphonate pamidronate) was injected i.v. Whole-body images were analyzed by using the multispectral Maestro imaging system. RESULTS: OsteoSense 750 signals in the paw joints were higher in ank/ank mice in all three age groups compared with controls. In the spine, significantly higher OsteoSense 750 signals were detected early, in 8-week-old ank/ank mice compared with controls, although minimal radiographic differences were noted at this time point. The molecular imaging changes in the ank/ank spine (8 weeks) were supported by histologic changes, including calcium apatite crystals at the edge of the vertebral bodies and new syndesmophyte formation. CONCLUSIONS: Changes in joint pathology of ank/ank mice, as evaluated by histologic and radiographic means, are qualitative, but only semiquantitative. In contrast, molecular imaging provides a quantitative assessment. Ankylosis in ank/ank mice developed simultaneously in distal and axial joints, contrary to the previous notion that it is a centripetal process. NIR imaging might be feasible for early disease diagnosis and for monitoring disease progression in ankylosing spondylitis.


Asunto(s)
Vértebra Cervical Axis/metabolismo , Vértebra Cervical Axis/patología , Calcificación Fisiológica , Imagen Molecular/métodos , Espondilitis Anquilosante/genética , Espondilitis Anquilosante/metabolismo , Animales , Vértebra Cervical Axis/química , Calcificación Fisiológica/genética , Inflamación/genética , Inflamación/metabolismo , Inflamación/prevención & control , Ratones , Ratones Transgénicos , Espondilitis Anquilosante/diagnóstico , Factores de Tiempo
16.
Pathol Res Pract ; 206(11): 788-91, 2010 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-20705400

RESUMEN

Atypical teratoid/rhabdoid tumor (AT/RT) is a distinctive neoplasm of young children characterized by diverse histology and fatal course. Adult presentation is rare. We describe the diagnostic problems associated with an AT/RT arising in the sellar region in a 46-year-old female. Vimentin, keratin, synaptophysin, CD34, SMA, PLAP, GFAP, S-100, NSE, desmin, MYF-4, LCA, and CD99 were performed on tissue obtained from the paraffin block. INI1 protein expression was immunohistochemically determined on tumor tissue. Electron microscopy was performed from the tissue block. The tumor was composed of large atypical "rhabdoid" cells having macronucleoli and abundant eosinophilic cytoplasm. Immunohistochemistry showed that the tumor cells were positive for vimentin, CD34, CD99, and reacted variably for keratin, synaptophysin, NSE, and SMA. All were negative for GFAP, S-100, desmin, MYF-4, and LCA. The tumor cells lacked nuclear expression of INI1. Electron microscopy revealed cells with large paranuclear intracytoplasmic collections of intermediate filaments. AT/RT should be considered when dealing with a malignant neoplasm with rhabdoid features, regardless of age. Immunohistochemistry is of importance in differentiating this entity from primitive neuroectodermal tumors (PNET) and carcinosarcomas. Lack of nuclear INI1 protein expression by immunohistochemical methods is required for a reliable diagnosis.


Asunto(s)
Neoplasias Encefálicas/patología , Enfermedades Raras , Tumor Rabdoide/patología , Silla Turca/patología , Teratoma/patología , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinosarcoma/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Tumores Neuroectodérmicos Primitivos/diagnóstico , Tumor Rabdoide/metabolismo , Teratoma/metabolismo
17.
J Neurosurg Spine ; 10(6): 513-21, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19558283

RESUMEN

OBJECT: The intervertebral disc (IVD) is a highly avascular structure that is occupied by highly specialized cells (nucleus pulposus [NP] cells) that have adapted to survive within an O(2) concentration of 2-5%. The object of this study was to investigate the effects of long-term hypoxic and normoxic tissue cultures of nonchondrodystrophic canine notochordal cells-cells that appear to protect the disc NP from degenerative change. METHODS: The authors obtained notochordal cells from nonchondrodystrophic canines according to their established methods and placed them into monolayer and 3D culture using sodium alginate globules under either hypoxic (3.5% O(2)) or normoxic (21% O(2)) conditions. Histological, immunohistochemical, scanning electron microscopy, and histomorphometric methods were used to evaluate the cells within the globules after 5 months in culture. RESULTS: Notochordal cells under in vitro hypoxic tissue culture conditions produced a highly complex, organized, 3D cellular construct that was strikingly similar to that observed in vivo. In contrast, traditional normoxic tissue culture conditions resulted in notochordal cells that failed to produce an organized matrix. Hypoxia resulted in a matrix rich in aggrecan and collagen II, whereas normoxic cultured cells did not produce any observable aggrecan or collagen II after 5 months of culture. CONCLUSIONS: Hypoxia induces notochordal cells to organize a complex 3D cellular/extracellular matrix without an external scaffold other than suspension within sodium alginate. These cells produce an extracellular matrix and large construct that shares exactly the same characteristics as the in vivo condition-robust aggrecan, and type II collagen production. Normoxic tissue culture conditions, however, lead to a failure of these cells to thrive and a lack of extracellular matrix production and significantly smaller cells. The authors suggest that future studies of NP cells and, in particular, notochordal cells should utilize hypoxic tissue culture conditions to derive meaningful, biologically relevant conclusions concerning possible biological/molecular interventions.


Asunto(s)
Disco Intervertebral/citología , Disco Intervertebral/fisiología , Notocorda/citología , Oxígeno/farmacología , Ingeniería de Tejidos/métodos , Agrecanos/metabolismo , Alginatos , Animales , Agregación Celular , Técnicas de Cultivo de Célula/métodos , Hipoxia de la Célula/fisiología , Tamaño de la Célula , Células Cultivadas , Colágeno Tipo II/metabolismo , Perros , Elasticidad , Matriz Extracelular/metabolismo , Matriz Extracelular/fisiología , Matriz Extracelular/ultraestructura , Ácido Glucurónico , Ácidos Hexurónicos , Microscopía Electrónica de Rastreo
18.
Exp Cell Res ; 313(20): 4120-9, 2007 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-17950726

RESUMEN

Progressive ankylosis (Ank and the human homolog, ANKH) is a transmembrane protein which regulates transport of inorganic pyrophosphate (PPi). ank/ank mice with a mutated ank gene, have calcification and bone ankylosis of the affected joints. In the course of studying these mutant mice, we found that they have microcytosis. These mutant mice have lower mean red blood cell volume (MCV) and lower hemoglobin content in red cells (mean corpuscular hemoglobin, MCH) than normal mice. Using quantitative real-time PCR analysis, we showed that Ank was expressed in the E/Meg bipotent precursor, BFU-E, CFU-E, but there was no Ank expression in the hemoglobinizing erythroblasts. Stable ANKH transfectants in K562 cells highly expressed two immature erythroid cell markers, E-cadherin and endoglin. Enhanced Erythropoietin (Epo) expression and downregulation of SHP-1 were detected in these transfectants. Consequently, the autocrine Epo-EpoR signaling pathway was activated, as evidenced by higher p-Tyr JAK2, p-Tyr EpoR and p-Tyr STAT5B in the ANKH transfectants. Our results revealed a novel function of ANKH in the promotion of early erythroid differentiation in K562 cells. We also showed that ank/ank mice have lower serum levels of Epo than the normal littermates, and this is the likely cause of microcytosis in these mutant mice.


Asunto(s)
Diferenciación Celular , Endocitosis , Células Eritroides/citología , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Animales , Comunicación Autocrina , Regulación hacia Abajo , Eritrocitos/citología , Eritrocitos/metabolismo , Células Precursoras Eritroides/citología , Células Precursoras Eritroides/metabolismo , Eritropoyetina/sangre , Regulación de la Expresión Génica , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Células K562 , Ratones , Ratones Mutantes , Proteínas de Transporte de Fosfato/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Receptores de Eritropoyetina/metabolismo , Transfección
19.
Pathol Res Pract ; 203(6): 467-71, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17418959

RESUMEN

Mature cystic teratoma of the ovary (MCTO) is the most common type of ovarian teratoma and also the most frequent tumor originating from germ cells. It is usually diagnosed in early adulthood and, by definition, is composed of well-differentiated tissues, which originate from all three germ cell layers. Unusual types of tissues can be found in MCTO, such as kidney, adrenal, and prostatic tissues. Malignant transformation is reported in less than 2% of teratomas. Squamous cell carcinoma is the most common malignancy arising in these otherwise benign tumors. We present the first case of MCTO containing a chordoma. The chordoma differentiation was supported by immunohistochemical staining and interphase fluorescence in situ hybridization (IP-FISH) technique showing 19% of the nuclei of the MCTO displaying polysomy for the chromosome X, while 28% of the chordoma nuclei showed chromosome 7 mosaicism. These results are concordant with previous studies, showing chromosomal anomalies in chromosomes X and 7 in MCTO and chordomas, respectively.


Asunto(s)
Diferenciación Celular , Transformación Celular Neoplásica/patología , Cordoma/diagnóstico , Neoplasias Ováricas/diagnóstico , Teratoma/diagnóstico , Adulto , Transformación Celular Neoplásica/química , Transformación Celular Neoplásica/genética , Cordoma/química , Cordoma/genética , Cordoma/patología , Cromosomas Humanos Par 7 , Cromosomas Humanos X , Diagnóstico Diferencial , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Queratinas/análisis , Antígeno Ki-67/análisis , Mosaicismo , Mucina-1/análisis , Neoplasias Ováricas/química , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Proteínas S100/análisis , Teratoma/química , Teratoma/genética , Teratoma/patología , Proteína p53 Supresora de Tumor/análisis , Vimentina/análisis
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA