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1.
Res Sq ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38045279

RESUMO

Deep-brain stimulation (DBS) is a potential novel treatment for memory dysfunction. Current attempts to enhance memory focus on stimulating human hippocampus or entorhinal cortex. However, an alternative strategy is to stimulate brain areas providing modulatory inputs to medial temporal memory-related structures, such as the nucleus accumbens (NAc), which is implicated in enhancing episodic memory encoding. Here, we show that NAc-DBS improves episodic and spatial memory in psychiatric patients. During stimulation, NAc-DBS increased the probability that infrequent (oddball) pictures would be subsequently recollected, relative to periods off stimulation. In a second experiment, NAc-DBS improved performance in a virtual path-integration task. An optimal electrode localization analysis revealed a locus spanning postero-medio-dorsal NAc and medial septum predictive of memory improvement across both tasks. Patient structural connectivity analyses, as well as NAc-DBS-evoked hemodynamic responses in a rat model, converge on a central role for NAc in a hippocampal-mesolimbic circuit regulating encoding into long-term memory. Thus, short-lived, phasic NAc electrical stimulation dynamically improved memory, establishing a critical on-line role for human NAc in episodic memory and providing an empirical basis for considering NAc-DBS in patients with loss of memory function.

2.
Stereotact Funct Neurosurg ; 99(6): 474-483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34474415

RESUMO

INTRODUCTION: A subgroup of patients with autism spectrum disorder (ASD) show self or heteroaggression, dyscontrol episodes, and others are of obsessive-compulsive disorder (OCD) profile; some of them are resistant to medical and behavioural treatment. We describe the long-term outcome in a group of these patients, treated with radiofrequency brain lesions or combined stereotactic surgery and Gamma Knife (GK) radiosurgery. METHODS: We reviewed the medical records of 10 ASD patients with pathological aggressiveness and OCD, who had undergone radiofrequency lesions and/or radiosurgery with GK in our institution. RESULTS: The 10 patients had a significant reduction of their symptoms (PCQ 39.9 and 33, OAS 11.8 and 5, CYBOCS-ASD 30.4 and 20), preoperatively and in the last follow-up, respectively; p < 0.005 (in all cases), although all but 2 needed more than 1 treatment to maintain this improvement. CONCLUSIONS: We observed a marked improvement in behaviour, quality of life, and relationship with the environment in all our 10 patients after the lesioning treatments, without long-lasting side effects.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Radiocirurgia , Transtorno do Espectro Autista/cirurgia , Transtorno Autístico/cirurgia , Humanos , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
3.
World Neurosurg ; 155: e168-e176, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34403796

RESUMO

BACKGROUND: Deep brain stimulation of the nucleus accumbens, ventral striatum, or internal capsule region has shown a 45%-60% response rate in adults with severe treatment-refractory obsessive-compulsive disorder, regardless of which target is used. We sought to improve the effectiveness of deep brain stimulation by placing the electrode along a trajectory including these 3 targets, enabling a change of stimulation site depending on the patient's response. METHODS: This study used the medical records of 14 patients from 4 different Spanish institutions: 7 from the Hospital Universitario La Princesa, 3 from the Hospital Universitario Central de Asturias, 2 from Hospital Universitario Fundación Jiménez Díaz, and 2 from Hospital Universitari Son Espases. All patients were operated on under the same protocol. Qualitative and quantitative data were collected. RESULTS: Of 14 patients, 11 showed significant improvement in obsessive-compulsive disorder symptoms, as evident in a reduction ≥35% in Yale-Brown Obsessive Compulsive Scale scores following stimulation relative to preoperative scores. Seven patients responded to stimulation at the nucleus accumbens (the first area we set for stimulation), whereas 4 patients needed to have the active contact switched to the internal capsule to benefit from stimulation. CONCLUSIONS: Deep brain stimulation of the nucleus accumbens, internal capsule, and ventral striatum significantly benefited our cohort of patients with medication-resistant obsessive-compulsive disorder. Electrode insertion through the 3 main targets might confer additional therapeutic efficacy.


Assuntos
Estimulação Encefálica Profunda , Cápsula Interna/fisiopatologia , Núcleo Accumbens/fisiopatologia , Transtorno Obsessivo-Compulsivo/terapia , Estriado Ventral/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtorno Obsessivo-Compulsivo/fisiopatologia , Resultado do Tratamento , Adulto Jovem
4.
Neurocirugía (Soc. Luso-Esp. Neurocir.) ; 32(4): 161-169, jul.- ago. 2021. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-222727

RESUMO

Background and objective Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. Methods Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. Results ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). Conclusions In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions (AU)


Antecedentes y objetivo El edema cerebral es una complicación grave y frecuente en pacientes con traumatismo craneoencefálico (TCE). La resonancia de tensor de difusión (DTI-RM) es considerada como una técnica de imagen muy útil para valorar la integridad de la sustancia blanca tras un TCE. El objetivo de este estudio prospectivo y observacional es valorar las características del edema vasogénico pericontusional de pacientes traumáticos y comparar dichas zonas con el edema vasogénico de pacientes con tumores cerebrales. También se ha incluido un grupo control. Pacientes y métodos Se ha empleado la DTI-RM para cuantificar el coeficiente de difusión aparente (ADC) y la anisotropía fraccional (AF) en las zonas de edema vasogénico en pacientes con contusiones cerebrales traumáticas y tumores cerebrales. Las mediciones del grupo control se hicieron tanto en la sustancia gris como en la sustancia blanca. Se incluyeron 15 pacientes con TCE, 18 pacientes con tumores cerebrales y 15 controles. Resultados Los valores del ADC y de la AF fueron similares en los pacientes con TCE y tumores cerebrales (p=0.27 para los valores de AF; p=0,79 para los valores de ADC). Respecto a los controles, tanto los pacientes con TCE como con tumores cerebrales presentaron valores más elevados del ADC y valores más bajos de la AF. Las diferencias en estas variables entre los pacientes con TCE y los controles fueron estadísticamente significativas (p<0,05) (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Imagem de Difusão por Ressonância Magnética , Estudos Prospectivos , Anisotropia
5.
Neurocirugia (Astur : Engl Ed) ; 32(4): 161-169, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34218876

RESUMO

BACKGROUND AND OBJECTIVE: Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. METHODS: Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. RESULTS: ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). CONCLUSIONS: In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions.


Assuntos
Lesões Encefálicas Traumáticas , Imagem de Tensor de Difusão , Anisotropia , Lesões Encefálicas Traumáticas/complicações , Edema/diagnóstico por imagem , Humanos , Estudos Prospectivos
6.
Artigo em Inglês | MEDLINE | ID: mdl-33202865

RESUMO

There is alarming population wide prevalence of low adolescent physical activity as this represents a risk factor for later chronic disease development. There is evidence to suggest that schools with strong wellness policies have students that are more frequently active. We designed an intervention to enhance students' physical activity levels in five majority Latinx, underserved school districts. Evaluation consisted of assessment of written quality of school-district wellness policies; observation of student's physical activity during leisure times; and after-school program practices and policies. We examined one of these district's results more closely, the only participating district with a community coalition, and extracted lessons learned. On the physical activity section of the wellness policy, this district covered a moderate extent of recommended content areas using weak language. Compared to previous reports, we identified low vigorous activity levels for girls and boys at baseline (respectively, 12% and 18%). Finally, we identified that of four after school program sites assessed at baseline, no program reported the recommended 50% or more of program time dedicated to physical activity. Based on these evaluation findings, additional strategies are urgently needed to encourage all students and particularly more girls to be physically active throughout the school day.


Assuntos
Meio Ambiente , Exercício Físico , Política de Saúde , Promoção da Saúde , Avaliação de Programas e Projetos de Saúde , Adolescente , Feminino , Promoção da Saúde/legislação & jurisprudência , Promoção da Saúde/métodos , Humanos , Los Angeles , Masculino , Pobreza/estatística & dados numéricos , Instituições Acadêmicas
7.
Medicine (Baltimore) ; 99(43): e22879, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33120830

RESUMO

Cerebral edema is a frequent and serious complication in traumatic brain injury (TBI) patients. The objective is to study the effect of dexamethasone in patients with brain contusions, and to assess its effect on the vasogenic component of the pericontusional edema.Prospective-observational study to quantify, using magnetic resonance imaging, the volume of the edema before and after 10 days of dexamethasone in patients with brain contusions. Using diffusion tensor imaging, we have examined the effect of dexamethasone on fractional anisotropy (FA) and apparent diffusion coefficient (ADC). To assess changes, the pre- and post-treatment values for each patient were compared using a paired-samples Student t test.We included 30 TBI patients, 15 in each group. The volume of the vasogenic edema in the group of patients treated with dexamethasone decreased from 22 to 19 mL and this decrease was statistically significant (P < .05). Nevertheless, in the non-steroids group the volume of the vasogenic edema increased from 11 to 15 mL. There was a significant decrease in the ADC value (from 1.78-1.59; P < .05); and a significant increase in the FA value (0.09-0.11; P < .05) in the patients treated with dexamethasone.Using diffusion tensor imaging we have shown in a selected group of TBI patients with vasogenic pericontusional edema, a reduction of edema volume, a decrease in the ADC and an increase in the FA after treatment with dexamethasone. However, we have no data if such results are beneficial in terms of improving functional outcome.


Assuntos
Anti-Inflamatórios/uso terapêutico , Edema Encefálico/tratamento farmacológico , Lesões Encefálicas Traumáticas/complicações , Dexametasona/uso terapêutico , Imagem de Tensor de Difusão/métodos , Adulto , Idoso , Anisotropia , Anti-Inflamatórios/administração & dosagem , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Estudos de Casos e Controles , Dexametasona/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Espanha/epidemiologia
8.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32709492

RESUMO

BACKGROUND AND OBJECTIVE: Cerebral edema is a frequent and serious complication of traumatic brain injury (TBI). Diffusion tensor imaging (DTI) is considered a useful technique to assess white matter integrity after TBI. The objective of this prospective, observational study was to assess the characteristics of the vasogenic edema in the traumatic pericontusional tissue and compare it to the vasogenic edema found in brain tumors. We also included a control group. METHODS: Using DTI, the Apparent diffusion coefficient (ADC) and Fractional anisotropy (FA) were measured in the area of vasogenic edema in both TBI and tumor patients. The measurements in the control group were done in the gray and white matter. We included 15 TBI patients, 18 tumor patients and 15 controls. RESULTS: ADC and FA showed no differences between TBI and tumor patients (p=0.27 for AF; p=0.79 for ADC). Compared to healthy controls, TBI and tumor patients presented higher ADC values and lower FA values. The differences between TBI and controls were statistically significant (p<0.05). CONCLUSIONS: In this prospective observational study using DTI-MRI in a selected group of mild and moderate TBI patients with vasogenic pericontusional edema we have shown that there were no significant differences of the ADC and FA values compared to brain tumor patients. Furthermore, healthy controls showed significant lower ADC values and higher FA values compared to TBI and tumor patients. Future studies, using DTI-MRI, should address whether any therapy has a favorable impact on the vasogenic edema of TBI patients with brain contusions.

9.
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 , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
10.
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
11.
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
12.
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
13.
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
15.
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
16.
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
17.
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
18.
Investig. segur. soc. salud ; 4: 93-112, 2002. ilus
Artigo em Espanhol | LILACS, COLNAL | ID: lil-600441

RESUMO

Antecedentes: los servidos de salud deben buscar siempre el mejoramiento de la calidad de la atención en salud. Una de las formas de lograrlo es colocando a disposición de los médicos mecanismos de educación continuada. El conocimiento actualizado es un factor esencial cuando se quiere lograr la excelencia en el acto médico y la educación continuada es parte de la solución al problema. La práctica médica requiere profesionales permanentemente actualizados. Objetivos: evaluar una estrategia de intervención en educación médica continuada (EMC) para los médicos generales de primer nivel de atención 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 después del curso se evaluaron conocimientos con un examen y desempeño mediante la auditoría de una muestra de historias clínicas (n = 234). Resultados: de los 140 médicos de la red. el 60% son hombres y el 40% mujeres con un promedio de edad de 32.5 años. Realizando el año de servicio social obligatorio hay 20.6%. Se inscribieron 98 médicos (88% del total de 140) y asistieron al curso 54 (49.4%). Al menos al 50% del curso asistieron 54 médicos (55%), 30 hombres (56%) y 24 mujeres (44%). La evaluación del curso por los participantes fue: contenidos, 4.36; cumplimiento, 4.43, y materiales, 3.92. El promedio en los exámenes previos fue de 2.27/5.0 (DS 0.90) y posteriores fue de 2.90 (DS 0.55). Se hicieron auditorías 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 mejoraría significativa entre los asistentes en los aspectos administrativos, de anamnesis y de diagnóstico, y a 112 historias de control de crecimiento y desarrollo en pediatría (76 antes y 36 después de la intervención) que en la evaluación pre-intervención mostraron pobres resultados en la anamnesis e intervenciones y mejoría significativa entre los asistentes en los aspectos administrativos. 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 limitado y por ello es recomendable considerar la realización de cursos específicos y de mayor profundidad. Se sugiere añadir a la evaluación de conocimientos el uso de nuevas estrategias como la auditoría de las historias clínicas, para así establecer el impacto de la EMC en la atención de los pacientes.


Background: Health services should always seek to improve the quality of health care. One of the ways to achieve this is by making continuing education mechanisms available to physicians. Up-to-date knowledge is an essential factor in achieving excellence in medical practice and continuing education is part of the solution to the problem. Medical practice requires permanently updated professionals. Objectives: to evaluate an intervention strategy in continuing medical education (CME) for general practitioners at the first level of care of the southwestern network of the District Health Secretariat. Population and methodology: 82 out of 140 physicians were evaluated to define the needs in CME and to define the contents of a refresher course. Before and after the course, knowledge was evaluated with a test and performance was assessed by auditing a sample of medical records (n = 234). Results: of the 140 physicians in the network, 60% were men and 40% women with an average age of 32.5 years. There are 20.6% performing the year of compulsory social service. Ninety-eight physicians registered (88% of the total 140) and 54 (49.4%) attended the course. At least 50% of the course was attended by 54 physicians (55%), 30 men (56%) and 24 women (44%). The evaluation of the course by the participants was: contents, 4.36; compliance, 4.43, and materials, 3.92. The average pre-test score was 2.27/5.0 (SD 0.90) and post-test score was 2.90 (SD 0.55). We audited 122 first-time prenatal care records (78 before and 44 after the intervention) that showed, before the course, poor results in aspects related to diagnosis and interventions, and significant improvement among attendees in administrative, anamnesis and diagnostic aspects, and 112 pediatric growth and development records (76 before and 36 after the intervention) that in the pre-intervention evaluation showed poor results in anamnesis and interventions and significant improvement among attendees in administrative aspects. Conclusions and recommendations: the general practitioners confirmed the need for CME and their satisfaction with it. However, the impact of a short course with multiple topics is limited and therefore it is advisable to consider specific and more in-depth courses. It is suggested to add to the evaluation of knowledge the use of new strategies such as the audit of medical records, in order to establish the impact of the CME on patient care.


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