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1.
Brain Stimul ; 8(3): 645-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25814404

RESUMO

BACKGROUND: Deep Brain Stimulation (DBS) is thought to improve the symptoms of selected neurological disorders by modulating activity within dysfunctional brain circuits. To date, there is no evidence that DBS counteracts progressive neurodegeneration in any particular disorder. OBJECTIVE/HYPOTHESIS: We hypothesized that DBS applied to the fornix in patients with Alzheimer's Disease (AD) could have an effect on brain structure. METHODS: In six AD patients receiving fornix DBS, we used structural MRI to assess one-year change in hippocampal, fornix, and mammillary body volume. We also used deformation-based morphometry to identify whole-brain structural changes. We correlated volumetric changes to hippocampal glucose metabolism. We also compared volumetric changes to those in an age-, sex-, and severity-matched group of AD patients (n = 25) not receiving DBS. RESULTS: We observed bilateral hippocampal volume increases in the two patients with the best clinical response to fornix DBS. In one patient, hippocampal volume was preserved three years after diagnosis. Overall, mean hippocampal atrophy was significantly slower in the DBS group compared to the matched AD group, and no matched AD patients demonstrated bilateral hippocampal enlargement. Across DBS patients, hippocampal volume change correlated strongly with hippocampal metabolism and with volume change in the fornix and mammillary bodies, suggesting a circuit-wide effect of stimulation. Deformation-based morphometry in DBS patients revealed local volume expansions in several regions typically atrophied in AD. CONCLUSION: We present the first in-human evidence that, in addition to modulating neural circuit activity, DBS may influence the natural course of brain atrophy in a neurodegenerative disease.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Atrofia/terapia , Estimulação Encefálica Profunda , Fórnice/patologia , Hipocampo/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Atrofia/patologia , Feminino , Fórnice/metabolismo , Glucose/metabolismo , Hipocampo/metabolismo , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
2.
Rev. Soc. Colomb. Oftalmol ; 48(1): 58-67, 2015. ilus. graf.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-948863

RESUMO

Objetivo: Describir el caso clínico de una paciente con oclusión de la arteria central de la retina (OACR) bilateral posterior a la embolización de una malformación arterio ­ venosa facial congénita y revisar la literatura sobre el tema. Diseño del estudio: Reporte de caso. Metodología: Se reportó el caso de una paciente con oclusión de arteria central de la retina bilateral que consulta a la clínica Unidad Láser del Atlántico, Barranquilla ­ Colombia en agosto de 2013, se hizo revisión detallada de la historia clínica y se tomaron fotos a color y angiografía fluoresceïnica de la retina. Resultados: La paciente consulta por presentar pérdida de la visión en ambos ojos posterior a una terapia endovascular con embolesferas realizada como tratamiento para una malformación arterio - venosa localizada en la punta de la nariz desde la infancia. La angiografía fluoresceinica de la retina evidencia: 1. Oclusión de la arteria central de la retina bilateral. 2 Persistencia de perfusión en rama superior de bifurcación de arteria temporal inferior ojo derecho 3. Variante anatómica de arteria cilioretiniana ojo izquierdo. Conclusión: La mayoría de las obstrucciones de las arterias centrales de la retina resultan en pérdida severa y permanente de la visión, es por tal motivo que teniendo en cuenta las potenciales complicaciones de origen embólico de los procedimientos intervencionistas, los pacientes necesitan ser conscientes del riesgo que este tratamiento puede implicar. Oftalmólogos, radiólogos y demás personal a cargo de este tipo de procedimientos deben tener un alto índice de sospecha diagnóstica de una OACR ante una disminución repentina de la visión durante o inmediatamente después de este tipo de procedimientos intervencionistas. De igual manera se resalta la necesidad de la evaluación cuidadosa de angiografías para la detección de cualquier vaso colateral anormal antes de la embolización.


Objective: To describe the clinical case of a female patient with central retinal artery occlusion (CRAO) after an embolization procedure as a primary treatment for a congenital nasal vascular lesion, its evolutions and sequela and review the current literature about this subject. Study Design: Case report. Methods: We reported the case of a patient with central retinal artery occlusion, who presented at Clinica Unidad Laser del Atlantico on august 2013. Her medical record was reviewed and analyzed. Posterior segment photographs and fluorescein angiography were taken. Results: The patient was seen for visual loss of both eyes after endovascular therapy for a congenital malformation located at the tip of her nose, which was presented from birth. The fluorescein angiographic showed a central retinal artery occlusion in both eyes. Conclusion: Most of the obstruction of the central retinal arteries result in severe and permanent loss of vision, for that reason and considering account potential embolic complications of interventional procedures, patients need to be aware of the risk that this treatment it may involve. Ophthalmologists, radiologists and other healthcare physicians should have a high index of suspicion of CRAO after a sudden decrease of visual acuity during or immediately after the interventional procedures. Careful evaluation of angiography to detect any abnormal collateral vessel before embolization is recommended.


Assuntos
Oclusão da Artéria Retiniana/terapia , Embolização Terapêutica , Procedimentos Endovasculares
3.
Rev. Soc. Colomb. Oftalmol ; 47(2): 137-144, 2014. tab. graf.
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-967872

RESUMO

Objetivos: evaluar la concordancia entre la citología de impresión y el estudio de anatomía patológica en pacientes con nevus conjuntivales que consultaron al Departamento de Córnea de la Clínica Oftalmológica de Cartagena. Diseño del estudio: estudio de concordancia. Métodos: se tomaron 48 ojos de 44 pacientes con hiper o hipopigmentación conjuntival a los que se le realizó citología de impresión y estudio histopatológico comparándose los resultados. Resultados: durante Junio 2011 a Junio 2012 se incluyeron 48 pacientes con sospecha de nevus conjuntivales a los cuales se les realizó citología de impresión y estudio histopatológico. Tuvo más prevalencia el sexo femenino con 68.75%. La edad promedio fué de 34.5 años. Las lesiones encontradas en OD fueron el 52.08%. El 60.42% presentaron pigmento leve o moderado seguido de un 35.42% de pacientes con abundante pigmentación. La localización más común de la lesión fue la conjuntiva bulbar con 93.75%. La citología de impresión resultó positiva para nevus en el 89.58% mientras que la patología arrojó resultados de nevus sub-epitelial en un 35.42%, seguido de nevus compuesto y de unión en el 33.33 y 20.83% respectivamente, y ausencia de nevus en el 10.42%. La sensibilidad de la citología de impresión fue de 93.02% con una especificidad del 40%. Conclusiones: la citología de impresión es un método altamente sensible para la detección de nevus conjuntivales y puede ser utilizado como prueba de tamizaje.


Objectives: to evaluate the concordancebetween impression cytology and pathology evaluation in patients with conjunctival nevus attending Cornea Clinic at Clinica Oftalmológica de Cartagena. Study Design: concordance study Methods: We evaluated 48 eyes from 44 patients with conjunctival hyper or hypopigmentation whom underwent impression cytology and histopathology assessment to find concordance between two methods. Results: during June 2011 to June 2012, we included 48 patients with suspected conjunctival nevus whom underwent impression cytology and histopathology study. Female prevalence was 68.75%. Average age was 34.5 years. Lesions were found in right eye in 52.08% of patients. 60.42% had moderate or mild pigment followed by 35.42% with abundant pigment. The most common location of injury was the bulbar conjunctiva with 93.75%. Impression cytology was positive for nevus in 89.58%, while pathology studies showed subepithelial nevus in 35.42% of cases, followed by compound nevus and union nevus with 33.33% and 20.83% respectively. 10.42% of patients showed absence of nevus. Sensitivity of impression cytology was 93.02% while specificity of the test achieved 40%. Conclusions: impression cytology is a highly sensitive method to detect conjunctival nevi and can be used as a screening test.


Assuntos
Neoplasias Oculares/diagnóstico , Biologia Celular/tendências , Técnicas de Diagnóstico Oftalmológico/tendências , Nevo/diagnóstico
4.
Genes Chromosomes Cancer ; 51(6): 606-17, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22371336

RESUMO

Despite recent advances in the identification of the cytogenetic profiles of meningiomas, a significant group of tumors still show normal karyotypes or few chromosomal changes. The authors analyzed the cytogenetic profile of 50 meningiomas using fluorescence in situ hybridization and high-density (500 K) single nucleotide polymorphism (SNP) arrays. Our results confirm that del(22q) (52%) and del(1p) (16%) (common deleted regions: 22q11.21-22q13.3. and 1p31.2-p36.33) are the most frequent alterations. Additionally, recurrent monosomy 14 (8%), del(6q) (10%), del(7p) (10%), and del(19q) (4%) were observed, while copy number patterns consistent with recurrent chromosomal gains, gene amplification, and copy number neutral loss of heterozygosity (cnLOH) were either absent or rare. Based on their overall SNP profiles, meningiomas could be classified into: (i) diploid cases, (ii) meningiomas with a single chromosomal change [e.g., monosomy 22/del(22q)] and (iii) tumors with ≥2 altered chromosomes. In summary, our results confirm and extend on previous observations showing that the most recurrent chromosomal abnormalities in meningiomas correspond to chromosome losses localized in chromosomes 1, 22 and less frequently in chromosomes 6, 7, 14, and 19, while chromosomal gains and cnLOH are restricted to a small proportion of cases. Finally, a set of cancer-associated candidate genes associated with the TP53, MYC, CASP3, HDAC1, and TERT signaling pathways was identified, in cases with coexisting monosomy 14 and del(1p).


Assuntos
Deleção Cromossômica , Neoplasias Meníngeas/genética , Meningioma/genética , Adulto , Idoso , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Transdução de Sinais
5.
Ecol Appl ; 21(4): 1352-64, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21774435

RESUMO

Reliable assessment of fish origin is of critical importance for exploited species, since nursery areas must be identified and protected to maintain recruitment to the adult stock. During the last two decades, otolith chemical signatures (or "fingerprints") have been increasingly used as tools to discriminate between coastal habitats. However, correct assessment of fish origin from otolith fingerprints depends on various environmental and methodological parameters, including the choice of the statistical method used to assign fish to unknown origin. Among the available methods of classification, Linear Discriminant Analysis (LDA) is the most frequently used, although it assumes data are multivariate normal with homogeneous within-group dispersions, conditions that are not always met by otolith chemical data, even after transformation. Other less constrained classification methods are available, but there is a current lack of comparative analysis in applications to otolith microchemistry. Here, we assessed stock identification accuracy for four classification methods (LDA, Quadratic Discriminant Analysis [QDA], Random Forests [RF], and Artificial Neural Networks [ANN]), through the use of three distinct data sets. In each case, all possible combinations of chemical elements were examined to identify the elements to be used for optimal accuracy in fish assignment to their actual origin. Our study shows that accuracy differs according to the model and the number of elements considered. Best combinations did not include all the elements measured, and it was not possible to define an ad hoc multielement combination for accurate site discrimination. Among all the models tested, RF and ANN performed best, especially for complex data sets (e.g., with numerous fish species and/or chemical elements involved). However, for these data, RF was less time-consuming and more interpretable than ANN, and far more efficient and less demanding in terms of assumptions than LDA or QDA. Therefore, when LDA and QDA assumptions cannot be reached, the use of machine learning methods, such as RF, should be preferred for stock assessment and nursery identification based on otolith microchemistry, especially when data set include multispecific otolith signatures and/or many chemical elements.


Assuntos
Modelos Biológicos , Modelos Estatísticos , Membrana dos Otólitos/fisiologia , Dourada/fisiologia , Animais , Demografia , Metais/química , Metais/metabolismo , Membrana dos Otólitos/química
7.
Comp Biochem Physiol C Toxicol Pharmacol ; 149(2): 215-23, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19000779

RESUMO

Over the last three decades, the California sea hare, Aplysia californica, has played an increasingly important role as a model organism in the neurosciences. Since 1995, the National Resource for Aplysia has supported a growing research community by providing a consistent supply of laboratory-reared individuals of known age, reproductive status, and environmental history. The purpose of the present study was to resolve the key biological factors necessary for successful culture of large numbers of high quality larval Aplysia. Data from a sequence of five experiments demonstrated that algal diet, food concentration, and veliger density significantly affected growth, attainment of metamorphic competency, and survival of Aplysia larvae. The highest growth and survival were achieved with a mixed algal diet of 1:1 Isochrysis sp (TISO) and Chaetoceros muelleri (CHGRA) at a total concentration of 250 x 10(3) cells/mL and a larval density of 0.5-1.0 per mL. Rapid growth was always correlated with faster attainment of developmental milestones and increased survival, indicating that the more rapidly growing larvae were healthier. Trials conducted with our improved protocol resulted in larval growth rates of >14 microm/day, which yielded metamorphically competent animals within 21 days with survival rates in excess of 90%. These data indicate the important effects of biotic factors on the critical larval growth period in the laboratory and show the advantages of developing optimized protocols for culture of such marine invertebrates.


Assuntos
Criação de Animais Domésticos/métodos , Aplysia/crescimento & desenvolvimento , Dieta , Crescimento , Maturidade Sexual , Animais , Larva/crescimento & desenvolvimento , Densidade Demográfica
8.
Neuro Oncol ; 9(4): 438-46, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17704362

RESUMO

Tumor recurrence is the major clinical complication in meningiomas, and its prediction in histologically benign/grade I tumors remains a challenge. In this study, we analyzed the prognostic value of specific chromosomal abnormalities and the genetic heterogeneity of the tumor, together with other clinicobiological disease features, for predicting early relapses in histologically benign/grade I meningiomas. A total of 149 consecutive histologically benign/grade I meningiomas in patients who underwent complete tumor resection were prospectively analyzed. Using interphase fluorescence in situ hybridization, we studied the prognostic impact of the abnormalities detected for 11 different chromosomes, together with other relevant clinicobiological and histopathological characteristics of the disease, on recurrence-free survival (RFS) at 2.5, 5, and 10 years. From the prognostic point of view, losses of chromosomes 9, 10, 14, and 18 and del(1p36) were associated with a shorter RFS at 2.5, 5, and 10 years. Similarly, histologically benign/grade I meningiomas showing coexistence of monosomy 14 and del(1p36) in the ancestral tumor cell clone displayed a higher frequency of early relapses. In fact, coexistence of -14 and del(1p36) in the ancestral tumor cell clone, together with tumor size, represented the best combination of independent prognostic factors for the identification of those patients with a high risk of an early relapse. Our results indicate that patients with large histologically benign/grade I meningiomas carrying monosomy 14 and del(1p36) in their ancestral tumor cell clone have a high probability of relapsing early after diagnostic surgery. These findings suggest the need for closer follow-up in this small group of patients.


Assuntos
Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 1/genética , Neoplasias Meníngeas/genética , Meningioma/genética , Recidiva Local de Neoplasia/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Deleção Cromossômica , Células Clonais , Feminino , Humanos , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Masculino , Neoplasias Meníngeas/mortalidade , Neoplasias Meníngeas/patologia , Meningioma/mortalidade , Meningioma/patologia , Pessoa de Meia-Idade , Monossomia , Recidiva Local de Neoplasia/patologia , Prognóstico
9.
Eur J Immunol ; 34(2): 576-86, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14768063

RESUMO

Antibodies recognizing non-bilayer phospholipid arrangements (NPA) in membrane models and in cell membranes in vivo, triggered an autoimmune-like disease in mice. This exhibited features similar to human lupus and was induced by injecting mice either with the H308 monoclonal antibody specific to NPA, with sera from mice which already had developed the autoimmune disease, or with liposomes treated with the NPA inductors chlorpromazine or procainamide; or with these NPA inductors alone. All these procedures revealed the involvement of antibodies to non-bilayer phospholipids in inducing this autoimmune-like disease. Unraveling the mechanisms of these antibodies might contribute to a better understanding of the molecular and immunological basis of autoimmune diseases like lupus and, hopefully, towards the development of better therapeutic strategies.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Fosfolipídeos/imunologia , Animais , Antiarrítmicos/efeitos adversos , Antiarrítmicos/imunologia , Antipsicóticos/efeitos adversos , Antipsicóticos/imunologia , Doenças Autoimunes/patologia , Clorpromazina/efeitos adversos , Clorpromazina/imunologia , Modelos Animais de Doenças , Feminino , Lipossomos/imunologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Procainamida/efeitos adversos , Procainamida/imunologia , Organismos Livres de Patógenos Específicos
10.
Investig. segur. soc. salud ; 4(4): 93-112, ene.-dic. 2002. graf
Artigo em Espanhol | LILACS | ID: lil-600441

RESUMO

Antecedentes: Los servicios de salud deben buscar el mejoramiento de la calidad de la atencion en salud. Una de las formas de lograrlo es colocando a disposicion de los médicos mecanismos de educacion continada. El conocimiento actualizado es un factor esencial en la práctica médica y requiere profesionales actualizados. Objetivos: Evaluar una estrategía de intervención en educación médica continuada (EMC) para los médicos generales de primer nivel de la red del Sur Occidente de la Secretaría Distrital de Salud. Población y metodología: se evaluaron 82 de 140 médicos para definir las necesidades en EMC y definir los contenidos de un curso de actualización. Antes y despúes del curso se evaluaron conocimientos con un examen y desempeño mediante la auditoria de una muestra de historias clínicas (n=234). Resultados: de los 140 medicos de la red, el 60% son hombres y el 40% mujeres con un promedio de edad de 32.5 años. La evaluación del curso por los participantes fue: contenidos, 4,36 cumplimiento, 4,43, y materiales 3.92. El promediuo en los exámenes previos fue de 2.27/5.0 (DS0.90) y posteriores fue de 2.90 (DS 0.55). Se hicieron auditorias a 122 historias clínicas de control prenatal de primera vez (78 antes y 44 después de la intervención) que mostraron, antes del curso, pobres resultados en los aspectos relacionados con el diagnóstico y las intervenciones, y mejoría significativa entre los asistentes en los aspectos administrativos, de anamnesis y de diagnóstico, Conclusiones y Recomendaciones: Los médicos generales confirmaron la necesidad de EMC y su satisfacción al realizarla. Sin embargo, el impacto de un curso corto con múltiples temas es límitado y por ello es recomendabble considerar la realización de cursos específicos y de mayor profundidad. Se sugiere añadir a la evaluaciónde conocimientos, el uso de nuevas estrategias como la auditoría de las historías clínicas, para así establecer el impacto de la EMC en la atención de los pacientes.


Assuntos
Humanos , Educação Continuada , Avaliação Educacional , Médicos de Família , Medicina Baseada em Evidências
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