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1.
Mol Ther ; 26(5): 1354-1365, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29606504

RESUMEN

Glioblastoma (GBM) is the least treatable type of brain tumor, afflicting over 15,000 people per year in the United States. Patients have a median survival of 16 months, and over 95% die within 5 years. The chemokine receptor ACKR3 is selectively expressed on both GBM cells and tumor-associated blood vessels. High tumor expression of ACKR3 correlates with poor prognosis and potential treatment resistance, making it an attractive therapeutic target. We engineered a single chain FV-human FC-immunoglobulin G1 (IgG1) antibody, X7Ab, to target ACKR3 in human and mouse GBM cells. We used hydrodynamic gene transfer to overexpress the antibody, with efficacy in vivo. X7Ab kills GBM tumor cells and ACKR3-expressing vascular endothelial cells by engaging the cytotoxic activity of natural killer (NK) cells and complement and the phagocytic activity of macrophages. Combining X7Ab with TMZ allows the TMZ dosage to be lowered, without compromising therapeutic efficacy. Mice treated with X7Ab and in combination with TMZ showed significant tumor reduction by MRI and longer survival overall. Brain-tumor-infiltrating leukocyte analysis revealed that X7Ab enhances the activation of M1 macrophages to support anti-tumor immune response in vivo. Targeting ACKR3 with immunotherapeutic monoclonal antibodies (mAbs) in combination with standard of care therapies may prove effective in treating GBM.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Glioblastoma/inmunología , Glioblastoma/metabolismo , Receptores CXCR/antagonistas & inhibidores , Temozolomida/farmacología , Animales , Anticuerpos Monoclonales/metabolismo , Afinidad de Anticuerpos/inmunología , Antineoplásicos Inmunológicos/farmacología , Línea Celular Tumoral , Citotoxicidad Inmunológica/efectos de los fármacos , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Glioblastoma/diagnóstico , Glioblastoma/mortalidad , Humanos , Imagen por Resonancia Magnética , Ratones , Mortalidad , Unión Proteica/inmunología , Receptores CXCR/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
2.
PLoS Negl Trop Dis ; 10(2): e0004396, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26863440

RESUMEN

BACKGROUND: The transitional period between the oncosphere and the cysticercus of Taenia solium is the postoncospheral (PO) form, which has not yet been completely characterized. The aim of this work was to standardize a method to obtain T. solium PO forms by in vitro cultivation. We studied the morphology of the PO form and compared the expression of antigenic proteins among the PO form, oncosphere, and cysticerci stages. METHODOLOGY/PRINCIPAL FINDINGS: T. solium activated oncospheres were co-cultured with ten cell lines to obtain PO forms, which we studied at three stages of development--days 15, 30, and 60. A high percentage (32%) of PO forms was obtained using HCT-8 cells in comparison to the other cell lines. The morphology was observed by bright field, scanning, and transmission electron microscopy. Morphology of the PO form changed over time, with the six hooks commonly seen in the oncosphere stage disappearing in the PO forms, and vesicles and microtriches observed in the tegument. The PO forms grew as they aged, reaching a diameter of 2.5 mm at 60 days of culture. 15-30 day PO forms developed into mature cysticerci when inoculated into rats. Antigenic proteins expressed in the PO forms are also expressed by the oncosphere and cysticerci stages, with more cysticerci antigenic proteins expressed as the PO forms ages. CONCLUSIONS/SIGNIFICANCE: This is the first report of an in vitro production method of T. solium PO forms. The changes observed in protein expression may be useful in identifying new targets for vaccine development. In vitro culture of PO form will aid in understanding the host-parasite relationship, since the structural changes of the developing PO forms may reflect the parasite's immunoprotective mechanisms. A wider application of this method could significantly reduce the use of animals, and thus the costs and time required for further experimental investigations.


Asunto(s)
Antígenos Helmínticos/análisis , Taenia solium/anatomía & histología , Taenia solium/crecimiento & desarrollo , Animales , Western Blotting , Línea Celular , Técnicas de Cocultivo , Perfilación de la Expresión Génica , Humanos , Microscopía , Taenia solium/genética
3.
Gut ; 64(10): 1569-77, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25387891

RESUMEN

BACKGROUND: Diminutive (≤ 5 mm) colorectal polyps are common, and overwhelmingly benign. Routinely, after polypectomy, they are examined pathologically to determine the surveillance intervals. Advances in equipment and techniques, such as narrow-band imaging (NBI) colonoscopy, now permit reliable real-time optical diagnosis. METHODS: We conducted a randomised single-masked study involving three institutions to determine whether optical diagnosis of diminutive colorectal polyps meets clinical practice standards and reduces the need for histopathology. We randomly assigned eligible patients undergoing routine high-definition colonoscopy to optical diagnosis using near focus versus standard view, using computer-generated block sequence. By validated criteria, we rendered an optical diagnosis and a confidence level (high vs low) for all polyps, using NBI. Our primary endpoint was the number of accurate high-confidence optical diagnoses compared with central blinded pathology in the two groups. We analysed data using intention to treat. FINDINGS: We enrolled 558 subjects, and randomly assigned 281 to near focus and 277 to standard view optical diagnosis. We detected 1309 predominantly diminutive (74.5%) and neoplastic (60.0%) polyps. Endoscopists were significantly more likely, OR 2.2 (95% CI 1.6 to 3.0, p<0.0001), to make a high-confidence optical diagnosis with near focus (85.1%) than standard (72.6%) view. High-confidence diagnoses had 96.4% and 92.0% negative predictive value, respectively. Of all polyps, 75.3% (95% CI71.3% to 78.9%) had a high-confidence accurate prediction using near focus, compared with 63.1% (95% CI 58.5% to 67.6%) using standard view. Optical versus histopathological diagnosis showed excellent agreement between the surveillance intervals, 93.5% in near focus and 92.2% in standard view. The median diagnosis time was 14 s. CONCLUSIONS: Real-time optical diagnosis using NBI colonoscopy may replace the pathology diagnosis for the majority of diminutive colorectal polyps. Using colonoscopy with near focus view increases the confidence level of the optical diagnosis. Optical diagnosis would be a paradigm shift in clinical practice of colonoscopy for colorectal cancer screening. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT01288833.


Asunto(s)
Pólipos del Colon/diagnóstico , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Imagen de Banda Estrecha/métodos , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Método Simple Ciego
4.
Am J Dermatopathol ; 36(10): 853-5, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23503318

RESUMEN

Chromhidrosis is a rare idiopathic disorder characterized by colored secretions most typically from the malar cheeks, axilla, or areolar regions. Histologically, chromhidrosis is notable for glandular structures with decapitation secretion indicating ectopic apocrine glands in the dermis, and the presence of lipofuscin pigments under ultraviolet fluorescence and in cytology smears. This case report describes a 26-year-old man who presented with a 2- to 3-year history of black-colored secretions on the bilateral malar cheeks, present on exertion or with squeezing of the cheeks. A 3-mm punch biopsy of the left cheek demonstrated histopathologic findings characteristic of chromhidrosis under hematoxylin and eosin staining and ultraviolet fluorescence. To our best knowledge, this is the second case report in the literature of an adult male being affected by chromhidrosis, and the first of an adult male with black-colored malar cheek secretions in chromhidrosis.


Asunto(s)
Trastornos de la Pigmentación/patología , Enfermedades de las Glándulas Sudoríparas/patología , Adulto , Glándulas Apocrinas/patología , Mejilla/patología , Humanos , Lipofuscina/metabolismo , Masculino
5.
J Clin Invest ; 121(6): 2336-49, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21606594

RESUMEN

Chronic rejection, manifested as small airway fibrosis (obliterative bronchiolitis [OB]), is the main obstacle to long-term survival in lung transplantation. Recent studies demonstrate that the airways involved in a lung transplant are relatively hypoxic at baseline and that OB pathogenesis may be linked to ischemia induced by a transient loss of airway microvasculature. Here, we show that HIF-1α mediates airway microvascular repair in a model of orthotopic tracheal transplantation. Grafts with a conditional knockout of Hif1a demonstrated diminished recruitment of recipient-derived Tie2⁺ angiogenic cells to the allograft, impaired repair of damaged microvasculature, accelerated loss of microvascular perfusion, and hastened denudation of epithelial cells. In contrast, graft HIF-1α overexpression induced via an adenoviral vector prolonged airway microvascular perfusion, preserved epithelial integrity, extended the time window for the graft to be rescued from chronic rejection, and attenuated airway fibrotic remodeling. HIF-1α overexpression induced the expression of proangiogenic factors such as Sdf1, Plgf, and Vegf, and promoted the recruitment of vasoreparative Tie2⁺ cells. This study demonstrates that a therapy that enhances vascular integrity during acute rejection may promote graft health and prevent chronic rejection.


Asunto(s)
Bronquiolitis Obliterante/fisiopatología , Terapia Genética , Vectores Genéticos/uso terapéutico , Rechazo de Injerto/prevención & control , Subunidad alfa del Factor 1 Inducible por Hipoxia/fisiología , Isquemia/etiología , Tráquea/trasplante , Adenoviridae/genética , Proteínas Angiogénicas/biosíntesis , Proteínas Angiogénicas/genética , Animales , Bronquiolitis Obliterante/inmunología , Hipoxia de la Célula , Supervivencia Celular , Quimiocina CXCL12/fisiología , Células Endoteliales/metabolismo , Células Endoteliales/patología , Células Endoteliales/trasplante , Rechazo de Injerto/inmunología , Rechazo de Injerto/fisiopatología , Subunidad alfa del Factor 1 Inducible por Hipoxia/deficiencia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Isquemia/fisiopatología , Isquemia/prevención & control , Ratones , Ratones Endogámicos , Ratones Noqueados , Microcirculación , Neovascularización Patológica/fisiopatología , Proteínas Tirosina Quinasas Receptoras/fisiología , Receptor TIE-2 , Receptores CXCR4/antagonistas & inhibidores , Receptores CXCR4/fisiología , Proteínas Recombinantes de Fusión/fisiología , Tráquea/irrigación sanguínea , Tráquea/inmunología , Tráquea/patología
6.
Rare Tumors ; 3(4): e43, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-22355498

RESUMEN

A 57-year-old with a 9-year history of increased abdominal girth, presented with increased abdominal pain, anemia, and acute renal failure. His past medical history was only remarkable for a previous lung cancer 21 years ago that was treated with a right upper lung lobectomy. A computed tomography (CT) scan of the patient's abdomen showed a solitary 20×20×25cm cystic splenic mass. The patient underwent an urgent splenectomy. Intra-operatively a large splenic cystic cavity was found with a solid inferior splenic mass. An exhaustive histological analysis of the splenic mass confirmed a clear cell carcinoma with low malignant potential that likely represented a metastatic lesion from the patient's previous distant lung cancer. Postoperatively the patient recovered well and at 1-year followup the patient demonstrated no further evidence of metastatic disease. This case is extremely unique and provides a very rare example of a metastatic solitary clear cell carcinoma to the spleen, with a presumed latency period of more than 20 years.

7.
Case Rep Crit Care ; 2011: 562516, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-24826323

RESUMEN

Acute necrotizing encephalopathy (ANE) is a severe neurological complication of influenza infection, including H1N1 influenza. Many cases of ANE have been reported in the pediatric literature, but very few cases have been described in adults. The cause of ANE remains unknown-the influenza virus is not known to be neurotropic, and evidence of direct viral involvement of the central nervous system (CNS) has not been demonstrated in the limited cases of ANE in which pathological specimens have been obtained. Here we report a fatal case of ANE from H1N1 influenza infection in an adult. Neuroimaging and postmortem analysis both showed widespread brain edema, necrosis, and hemorrhage, but molecular studies and postmortem pathology revealed no evidence of direct viral involvement of the CNS. This case of fatal ANE in an adult is consistent with the hypothesis generated from pediatric cases that the host immune response, and not direct viral invasion of the CNS, is responsible for pathogenesis of ANE.

8.
Infect Immun ; 75(11): 5158-66, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17698575

RESUMEN

The specific mechanisms underlying Taenia solium oncosphere adherence and penetration in the host have not been studied previously. We developed an in vitro adhesion model assay to evaluate the mechanisms of T. solium oncosphere adherence to the host cells. The following substrates were used: porcine intestinal mucosal scrapings (PIMS), porcine small intestinal mucosal explants (PSIME), Chinese hamster ovary cells (CHO cells), epithelial cells from ileocecal colorectal adenocarcinoma (HCT-8 cells), and epithelial cells from colorectal adenocarcinoma (Caco-2 cells). CHO cells were used to compare oncosphere adherence to fixed and viable cells, to determine the optimum time of oncosphere incubation, to determine the role of sera and monolayer cell maturation, and to determine the effect of temperature on oncosphere adherence. Light microscopy, scanning microscopy, and transmission microscopy were used to observe morphological characteristics of adhered oncospheres. This study showed in vitro adherence of activated T. solium oncospheres to PIMS, PSIME, monolayer CHO cells, Caco-2 cells, and HCT-8 cells. The reproducibility of T. solium oncosphere adherence was most easily measured with CHO cells. Adherence was enhanced by serum-binding medium with >5% fetal bovine serum, which resulted in a significantly greater number of oncospheres adhering than the number adhering when serum at a concentration less than 2.5% was used (P < 0.05). Oncosphere adherence decreased with incubation of cells at 4 degrees C compared with the adherence at 37 degrees C. Our studies also demonstrated that T. solium oncospheres attach to cells with elongated microvillus processes and that the oncospheres expel external secretory vesicles that have the same oncosphere processes.


Asunto(s)
Adhesión Celular/fisiología , Células Epiteliales/parasitología , Membrana Mucosa/parasitología , Taenia solium/fisiología , Animales , Células CHO , Células CACO-2 , Cricetinae , Cricetulus , Humanos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Reproducibilidad de los Resultados , Suero , Porcinos , Temperatura
9.
Neuron ; 53(2): 201-15, 2007 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-17224403

RESUMEN

Targeting of synaptic molecules to their proper location is essential for synaptic differentiation and plasticity. PSD-95/Dlg proteins have been established as key components of the postsynapse. However, the molecular mechanisms regulating the synaptic targeting, assembly, and disassembly of PSD-95/Dlg are not well understood. Here we show that PAR-1 kinase, a conserved cell polarity regulator, is critically involved in controlling the postsynaptic localization of Dlg. PAR-1 is prominently localized at the Drosophila neuromuscular junction (NMJ). Loss of PAR-1 function leads to increased synapse formation and synaptic transmission, whereas overexpression of PAR-1 has the opposite effects. PAR-1 directly phosphorylates Dlg at a conserved site and negatively regulates its mobility and targeting to the postsynapse. The ability of a nonphosphorylatable Dlg to largely rescue PAR-1-induced synaptic defects supports the idea that Dlg is a major synaptic substrate of PAR-1. Control of Dlg synaptic targeting by PAR-1-mediated phosphorylation thus constitutes a critical event in synaptogenesis.


Asunto(s)
Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/fisiología , Drosophila/fisiología , Unión Neuromuscular/fisiología , Proteínas Quinasas/fisiología , Sinapsis/fisiología , Proteínas Supresoras de Tumor/metabolismo , Animales , Animales Modificados Genéticamente , Recuperación de Fluorescencia tras Fotoblanqueo , Glucógeno Sintasa Quinasa 3 , Técnicas In Vitro , Unión Neuromuscular/metabolismo , Unión Neuromuscular/ultraestructura , Fosforilación , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas , Sinapsis/ultraestructura , Transmisión Sináptica/fisiología , Distribución Tisular
10.
FEBS Lett ; 580(9): 2351--2357, 2006 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-16616523

RESUMEN

Mallory bodies (MBs) are characteristic of several liver disorders, and consist primarily of keratins with transglutaminase-generated keratin crosslinks. We tested the effect of the transglutaminase-2 (TG2) inhibitor KCC009 on MB formation in a mouse model fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). KCC009 decreased DDC-induced liver enlargement without affecting MB formation or extent of liver injury. TG2 protein and activity increased after DDC feeding and localized within and outside hepatocytes. KCC009 inhibited DDC-induced hepatomegaly by affecting hepatocyte cell size rather than proliferation. Hence, TG2 is a potential mediator of injury-induced hepatomegaly via modulation of hepatocyte hypertrophy, and KCC009-mediated TG2 inhibition does not affect mouse MB formation.


Asunto(s)
Inhibidores Enzimáticos/administración & dosificación , Proteínas de Unión al GTP/antagonistas & inhibidores , Cuerpos de Inclusión/efectos de los fármacos , Isoxazoles/administración & dosificación , Hepatopatías/tratamiento farmacológico , Proteínas/metabolismo , Transglutaminasas/antagonistas & inhibidores , Animales , Tamaño de la Célula/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Dicarbetoxidihidrocolidina/administración & dosificación , Dicarbetoxidihidrocolidina/toxicidad , Proteínas de Unión al GTP/metabolismo , Hepatomegalia/inducido químicamente , Hepatomegalia/tratamiento farmacológico , Hepatomegalia/enzimología , Hepatomegalia/patología , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Queratinas/metabolismo , Hepatopatías/enzimología , Hepatopatías/patología , Ratones , Ratones Endogámicos C3H , Proteína Glutamina Gamma Glutamiltransferasa 2 , Transglutaminasas/metabolismo
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