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1.
Light Res Technol ; 55(4-5): 474-486, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469656

RESUMEN

This article describes the development of a device to investigate the non-visual responses to light: The Light-Dosimeter (lido). Its multidisciplinary team followed a user-centred approach throughout the project, that is, their design decisions focused on researchers' and participants' needs. Together with custom-made mountings and the software Lido Studio, the lidos provide researchers with a holistic solution to record participants' light exposure in the near-corneal plane in laboratory settings and under real-world conditions. Validation measurements with commercial equipment were deemed satisfying, as was the combining with data from other devices. The handling of the lidos and mountings and the use of the software Lido Studio during the trial period by various researchers and participants were successful. Despite some limitations, the lidos can help advance research on the non-visual responses to light over the coming years.

2.
J Endocrinol Invest ; 43(3): 369-379, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31621051

RESUMEN

PURPOSE: There are cognitive changes in primary hyperparathyroidism (PHPT) that improve with parathyroidectomy, but the mechanism of cognitive dysfunction has not been delineated. We assessed if cerebrovascular function is impaired in PHPT, improves post-parathyroidectomy and is associated with PTH level and cognitive dysfunction. METHODS: This is an observational study of 43 patients with mild hypercalcemic or normocalcemic PHPT or goiter. At baseline, cerebrovascular function (dynamic cerebral autoregulation and vasomotor reactivity) by transcranial Doppler and neuropsychological function were compared between all three groups. A subset underwent parathyroidectomy or thyroidectomy, and was compared 6 months post-operatively. RESULTS: Mean cerebrovascular and neuropsychological function was normal and no worse in PHPT compared to controls preoperatively. Higher PTH was associated with worse intracerebral autoregulation (r = - 0.43, p = 0.02) and worse cognitive performance on some tests. Post-parathyroidectomy, mood improved significantly, but changes did not differ compared to those having thyroidectomy (p = 0.84). There was no consistent improvement in cognition or change in vascular function in either surgical group. CONCLUSIONS: Although higher PTH was associated with worse intracerebral autoregulation, cerebrovascular function, cognition and mood were normal in mild PHPT. PTX did not improve vascular or cognitive function. The observed improvement in mood cannot be clearly attributed to PTX. Notwithstanding the small sample size, the results do not support changing current criteria for parathyroidectomy to include cognitive complaints. However, the associations between PTH, cognition and cerebral autoregulation merit future studies in those with more severe hyperparathyroidism.


Asunto(s)
Circulación Cerebrovascular/fisiología , Cognición/fisiología , Hiperparatiroidismo Primario/cirugía , Arteria Cerebral Media/diagnóstico por imagen , Paratiroidectomía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Hiperparatiroidismo Primario/psicología , Persona de Mediana Edad , Pruebas Neuropsicológicas , Resultado del Tratamiento
3.
Arq. bras. med. vet. zootec ; 69(2): 293-298, mar.-abr. 2017. mapa, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-833813

RESUMEN

Investigations of four roe deer corpses were carried out from May until October 2014, in the Veterinary Forensic Laboratory and in the Parasitic Diseases Clinic, in the Iasi Faculty of Veterinary Medicine. The roe deer were harvested by shooting during the trophy hunting season. The clinical examination of the shot specimens revealed the presence of a highly consistent number of extremely mobile apterous insects, spread on the face, head, neck, lateral body parts, abdominal regions, inguinal, perianal and, finally, all over the body. The corpses presented weakening, anemia and cutaneous modification conditions. Several dozen insects were prelevated in a glass recipient and preserved in 70º alcoholic solution in order to identify the ectoparasite species. The morphological characteristics included insects in the Diptera order, Hippoboscidae family, Lipoptena cervi species. These are highly hematophagous insects that by severe weakening are affecting the game health and trophy quality. Histological investigations of the skin revealed some inflammatory reactions caused by ectoparasite Lipoptena cervi. Lipoptena cervi was identified for the first time in Iasi County, Romania.(AU)


As investigações de quatro cadáveres de veados foram realizadas desde maio até outubro de 2014, no Laboratório Forense de Veterinária e na Clínica de Doenças Parasitárias, da Faculdade de Medicina Veterinária de Iasi. Os veados foram abatidos por tiro durante a temporada de caça troféu. O exame clínico dos espécimes revelou a presença de um número muito consistente de insetos ápteros extremamente móveis, espalhados pela face, pela cabeça, pelo pescoço, pelas partes do corpo laterais, pelas regiões abdominal, inguinal, perianal e, finalmente, por todo o corpo. Os cadáveres apresentavam condições de enfraquecimento, anemia e alterações cutâneas. Várias dezenas de insetos foram separados em um recipiente de vidro e preservados em solução alcoólica de 70º, a fim de se identificarem as espécies de ectoparasitos. As características morfológicas incluem os insetos da ordem Diptera, família Hippoboscidae, espécie Lipoptena Cervi. Estes são insetos hematófagos que estão enfraquecendo e afetando a qualidade de saúde de animais de caça e troféu. Investigações histológicas da pele revelaram algumas reações inflamatórias causadas pelo ectoparasita cervi Lipoptena. Lipoptena cervi foi identificado pela primeira vez no condado de Iasi, na Romênia.(AU)


Asunto(s)
Animales , Ciervos/parasitología , Dípteros , Infestaciones Ectoparasitarias/veterinaria , Rumanía
4.
J Chromatogr A ; 1468: 64-72, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27638141

RESUMEN

In this study, the surface of a microporous walled micro-capillary film (MMCF) was modified into a weak anion exchanger by coupling cyanuric chloride and 2-diethylaminoethylamine (DEAE) to the ethylene-vinyl alcohol (EVOH) matrix. Fourier transform infrared spectroscopy (FTIR) measurements of modified and unmodified MMCFs confirmed the addition of a triazine ring and DEAE onto the membrane. Binding of bovine serum albumin (BSA) at pH 7.2 was found to follow a Langmuir isotherm with a maximum equilibrium binding of 12.4mg BSA/mL adsorbent and 8.2mg BSA/mL adsorbent under static and flow conditions, respectively. The ion exchange capacity, determined by Mohr's titration of chlorine atoms displaced from the functionalised surface, was found to be 195±21µmol Cl-/mL of adsorber, comparable to commercial ion exchangers. BSA adsorption onto the ion exchanger was strongly pH-dependant, with an observed reduction in binding above pH 8.2. Frontal experiments of a BSA (5mg/mL) and lysozyme (5mg/mL) mixture demonstrated successful separation of BSA from lysozyme at more than 97% purity as verified by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Separation between similarly charged anionic molecules was also achieved using BSA (5mg/mL) and herring sperm DNA (0.25mg/mL). BSA was extracted at 100% purity, demonstrating the ability of MMCF-DEAE to remove significant DNA contamination from a protein solution. These experiments highlight the potential for MMCFs to be used for fast protein purification in preparative chromatography application.


Asunto(s)
Técnicas de Química Analítica/métodos , Proteínas/aislamiento & purificación , Adsorción , Aniones/química , Cromatografía de Afinidad , Electroforesis en Gel de Poliacrilamida , Muramidasa/metabolismo , Proteínas/análisis , Albúmina Sérica Bovina/análisis , Albúmina Sérica Bovina/aislamiento & purificación , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier
5.
J Chromatogr A ; 1394: 148-53, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25840664

RESUMEN

Micro-capillary film (MCF) membranes are effective platforms for bioseparations and viable alternatives to established packed bed and membrane substrates at the analytical and preparative chromatography scales. Single hollow fibre (HF) MCF membranes with varied microstructures were produced in order to evaluate the effect of the bore fluid composition used during hollow fibre extrusion on their structure and performance as cation-exchange adsorbers. Hollow fibres were fabricated from ethylene-vinyl alcohol (EVOH) copolymer through solution extrusion followed by nonsolvent induced phase separation (NIPS) using bore fluids of differing composition (100wt.% N-methyl-2-pyrrolidone (NMP), 100wt.% glycerol, 100wt.% water). All HFs displayed highly microporous and mesoporous microstructures, with distinct regions of pore size <1µm, 5-15µm and up to 50µm in diameter, depending upon proximity to the bore fluid. Scanning electron microscopy (SEM) revealed skins of pore size <1µm at the inner surface of HFs produced with water and glycerol, while NMP bore fluid resulted in a skinless inner HF surface. The HFs were modified for chromatography by functionalising the polymer surface hydroxyl groups with sulphonic acid (SP) groups to produce cation-exchange adsorbers. The maximum binding capacities of the HFs were determined by frontal analysis using lysozyme solutions (0.05-100mgml(-1)) for a flow rate of 1.0mlmin(-1). The NMP-HF-SP module displayed the largest maximum lysozyme binding capacity of all the fibres produced (40.3mg lysozyme/ml adsorbent volume), a nearly 2-fold increase over the glycerol and 10-fold increase over the water variants at the same sample flow rate. The importance of NMP as a bore fluid to hollow fibre membrane performance as a result of inner surface porosity was established with a view to applying this parameter for the optimisation of multi-capillary MCF performance in future studies.


Asunto(s)
Cromatografía por Intercambio Iónico/instrumentación , Glicerol/química , Membranas Artificiales , Polivinilos/química , Pirrolidinonas/química , Agua/química , Adsorción , Cromatografía por Intercambio Iónico/métodos , Muramidasa/análisis , Porosidad , Ácidos Sulfónicos/química
6.
Arq. bras. med. vet. zootec ; 66(3): 688-696, 06/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-718079

RESUMEN

In autumn 2011 in cyprinid farms located in Iasi on the Jijia river, several infections with bacterial strains and macroscopical external cysts on the skin were diagnosedwhich developed as a result of the stress induced by biotic and abiotic factors. On the examination of the cyst contents the presence of numerous spores was observed, mostly of the Dermocystidium sp genusThe samples were taken from the common carp (Cyprinus carpio) and crucian carp (Carassius auratus gibelio) species from the fish farm as well as from the Jijia River. 35 fish were examined, all of them showing cysts, fragmentation of their dorsal fin and congestion of the gills. Histological examination of the skin showed a field of multiple dermal cysts with round light eosinophilic formations (14-16µm) containing a central refractable body similar to that reported for Dermocystidium sp. Gills samples were taken from the affected areas for the SEM examination with the purpose of evaluating not only aspects of normal morphology, but also aspects of some modifications of the affected areas as well as the presence of the etiologically incriminated bacteria Pseudomonas fluorescens. The isolates were identified through phenotypic methods. All the strains that showed mobility and oxidase-positivity were tested using API 20 NE strip. Consequently, they were taxonomically grouped into the species Pseudomonas fluorescens. The scanning electron microscope (SEM) was used for the first time in the characterization of the bacterial lesions produced by Pseudomonas strains on Cyprinus carpio and Carassius auratus gibelio gills. The diagnosis of septicemia with conditional pathogen species of Pseudomonas fluorescens was correlated with the results of the physico-chemical investigations of water and the data concerning the breeding conditions of the investigated livestock...


No outono de 2011, em fazendas de ciprinídeos localizadas em Iasi, no rio Jijia, diversas infecções bacterianas e cistos externos macroscópicos na pele se desenvolveram como resultado do estresse induzido por fatores bióticos e abióticos. No exame do conteúdo dos cistos, a presença de diversos esporos foi observada, a maioria do gênero Dermocystidium sp. As amostras foram colhidas das seguintes espécies: carpa comum (Cyprinus carpio) e carpa cruciana (Carassius auratus gibelio) de fazenda piscícola, além do rio Jijia. Assim sendo, 35 peixes foram examinados, todos demonstrando cistos, fragmentação da barbatana dorsal e congestão das guelras. O exame histológico da pele mostrou um campo de múltiplos cistos dérmicos com formações circulares claras eosinofílicas (14-16µm) contendo corpo central refratado similar ao relatado para Dermocystidium sp. Amostras de guelras foram retiradas das áreas afetadas para exame MEV, com o propósito de se avaliar não apenas os aspectos da morfologia normal, mas também os aspectos de algumas modificações das áreas afetadas, além da presença da bactéria etiologicamente incriminada: Pseudomonas fluorescens. Os isolados foram identificados por meio de métodos fenotípicos. Todas as amostras que mostraram mobilidade e positividade-oxidase foram testadas usando-se fita API 20 NE. Consequentemente, estas foram taxonomicamente agrupadas na espécie Pseudomonas fluorescens. O microscópio eletrônico de varredura (MEV) foi usado pela primeira vez na caracterização de lesões bacterianas produzidas por Pseudomonas nas guelras de Cyprinus carpio e Carassius auratus gibelio. O diagnóstico de septicemia com espécies condicionais de patogênico de Pseudomonas fluorescens foi correlacionado com os resultados das investigações físico-químicas da água e de dados sobre as condições de reprodução dos animais investigados...


Asunto(s)
Animales , Carpas/microbiología , Carpas/parasitología , Dermcidinas , Infecciones Bacterianas/veterinaria , Enfermedades Parasitarias en Animales , Pseudomonas fluorescens/aislamiento & purificación , Factores Abióticos , Factores Bióticos
7.
Arh Hig Rada Toksikol ; 65(1): 29-36, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24670332

RESUMEN

A frequently encountered exposure profile for hand-arm vibration in contemporary occupational setting comprises workers with a long history of intermittent exposure but without detectable signs of hand-arm vibration syndrome (HAVS). Yet, most of the published studies deal with developed HAVS cases, rarely discussing the biological processes that may be involved in degradation of manual dexterity and grip strength when it can be most beneficial - during the asymptomatic stage. In the present paper, a group of 31 male asymptomatic vibration-exposed workers (according to the Stockholm Workshop Scale) were compared against 30 male controls. They were tested using dynamometry and dexterimetry (modelling coarse and fine manual performance respectively) and cold provocation was done to detect possible differences in manual performance drop on these tests. The results showed reduced manual dexterity but no significant degradation in hand grip strength in the exposed subjects. This suggests that intermittent exposure profile and small cumulative vibration dose could only lead to a measurable deficit in manual dexterity but not hand grip strength even at non-negligible A(8) levels and long term exposures.


Asunto(s)
Monitoreo del Ambiente/métodos , Fuerza de la Mano/fisiología , Síndrome por Vibración de la Mano y el Brazo/diagnóstico , Síndrome por Vibración de la Mano y el Brazo/fisiopatología , Exposición Profesional/efectos adversos , Vibración/efectos adversos , Adulto , Análisis de Varianza , Síndrome por Vibración de la Mano y el Brazo/etiología , Humanos , Masculino , Análisis Multivariante , Dinamómetro de Fuerza Muscular , Proyectos Piloto , Trastornos Somatosensoriales/diagnóstico , Trastornos Somatosensoriales/etiología , Trastornos Somatosensoriales/fisiopatología
8.
AJNR Am J Neuroradiol ; 34(3): 518-23, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22918429

RESUMEN

BACKGROUND AND PURPOSE: CNS complications are often seen after heart surgery, and postsurgical disruption of the BBB may play an etiologic role. The objective of this study was to determine the prevalence of MR imaging-detected BBB disruption (HARM) and DWI lesions after cardiac surgery. MATERIALS AND METHODS: All patients had an MRI after cardiac surgery. For half the patients (group 1), we administered gadolinium 24 hours after surgery and obtained high-resolution DWI and FLAIR images 24-48 hours later. We administered gadolinium to the other half (group 2) at the time of the postoperative scan, 2-4 days after surgery. Two stroke neurologists evaluated the images. RESULTS: Of the 19 patients we studied, none had clinical evidence of a stroke or delirium at the time of the gadolinium administration or the scan, but 9 patients (47%) had HARM (67% in group 1; 30% in group 2; P = .18) and 14 patients (74%) had DWI lesions (70% in group 1; 78% in group 2; P = 1.0). Not all patients with DWI lesions had HARM, and not all patients with HARM had DWI lesions (P = .56). CONCLUSIONS: Almost half the patients undergoing cardiac surgery have evidence of HARM, and three-quarters have acute lesions on DWI after surgery. BBB disruption is more prevalent in the first 24 hours after surgery. These findings suggest that MR imaging can be used as an imaging biomarker to assess therapies that may protect the BBB in patients undergoing heart surgery.


Asunto(s)
Barrera Hematoencefálica/patología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Imagen por Resonancia Magnética/métodos , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología , Anciano , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del Tratamiento
9.
J Med Life ; 5(2): 145-8, 2012 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-22802879

RESUMEN

RATIONALE: There is little knowledge regarding mullerian adenosarcoma and its metastasizing pattern. AIM: Our objective was to evaluate the impact on the prognostic of the patient brought by tumor metastasizing to the retroperitoneum, to analyze the particularities of the treatment in such cases and to bring a significant change in the early therapeutic attitude to mullerian adenosarcomas. METHODS AND RESULTS: We present a first case report of a hypervascularized retroperitoneal metastasis from an initial low-grade uterine adenosarcoma. The presence of such a metastasis brought the worst prognostic factor to the patient. CONCLUSIONS: We consider that in front of a macroscopic polypoid mass there should be an active change in the diagnosis and in the therapeutic attitude. The frequent confusion between similar histopathological entities with different aggressiveness states and specific treatment responses, the poor outcome at advanced tumor stages, frequently in young patients, should trigger a universal remodeling in approaching these tumors.


Asunto(s)
Adenosarcoma/patología , Neoplasias Retroperitoneales/irrigación sanguínea , Neoplasias Retroperitoneales/secundario , Neoplasias Uterinas/patología , Anciano , Resultado Fatal , Femenino , Humanos , Invasividad Neoplásica , Neoplasias Retroperitoneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Ultrasonografía
10.
Neurology ; 78(4): 250-5, 2012 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-22238418

RESUMEN

OBJECTIVE: To determine whether unihemispheral hemodynamic failure is independently associated with cognitive impairment among participants in the National Institute of Neurological Disorders and Stroke-sponsored, multicenter, randomized clinical trial, Randomized Evaluation of Carotid Occlusion and Neurocognition (RECON). METHODS: Forty-three patients were randomized into RECON after recent symptomatic carotid artery occlusion and asymmetrically increased oxygen extraction fraction (OEF) by PET (OEF ratio >1.13), indicating stage II hemodynamic failure on the side of occlusion. The PET-positive patients were compared with 28 RECON-enrolled patients who met all clinical and radiographic inclusion/exclusion criteria but had no OEF asymmetry. A multivariable regression compared patients with PET OEF >1.13 or ≤1.13, stratifying by TIA vs. stroke as the qualifying event. The dependent variable was a composite neurocognitive score derived from averaging age-normalized z scores on a test battery that included global and internal carotid artery (ICA) side-relevant hemisphere-specific tests. RESULTS: There were no differences in demographic, clinical, or radiologic characteristics between the PET-positive and PET-negative patients except for PET OEF asymmetry. The unadjusted average neurocognitive z score was -1.45 for the PET-positive and -1.25 for the PET-negative patients, indicating cognitive impairment in both groups but no difference between them (p = 0.641). After adjustment for age, education, side of occlusion, depression, and previous stroke, there was a significant difference between PET-positive and PET-negative patients among those with TIA as a qualifying event (average z score = -1.41 vs. -0.76, p = 0.040). Older age and right ICA side were also significant in this model. CONCLUSION: Hemodynamic failure is independently associated with cognitive impairment in patients with carotid occlusion. This finding establishes the physiologic parameter upon which the extracranial-intracranial bypass will be tested.


Asunto(s)
Circulación Cerebrovascular , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/psicología , Anciano , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/fisiopatología , Enfermedades de las Arterias Carótidas/psicología , Trastornos del Conocimiento/diagnóstico por imagen , Estudios de Cohortes , Escolaridad , Femenino , Lateralidad Funcional , Humanos , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/fisiopatología , Ataque Isquémico Transitorio/psicología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Destreza Motora , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/psicología , Prueba de Secuencia Alfanumérica , Percepción Visual , Pruebas de Asociación de Palabras
12.
J Med Life ; 3(1): 19-25, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20302193

RESUMEN

UNLABELLED: The aim of this study is to evaluate effective prognostic factors in the evolution of patients with retroperitoneal fibrosis and to establish the validity of fractal analysis in determining the disease severity in these patients. MATERIAL AND METHODS: This study included 19 patients (M/F: 5/14) treated for idiopathic retroperitoneal fibrosis and bilateral obstructive renal failure between Jan 2004-Dec 2008. Patients were identified retrospectively, searching for patients diagnosed with IRF, after retroperitoneal biopsy or, in most cases the diagnosis rested on radiological findings, especially CT, with identification of a retroperitoneal mass, the absence of other demonstrable renal or ureteric disease or any other pathology that could explain the findings. CT was very useful in describing the retroperitoneal mass around the aorta and inferior vena cava, the extent of the lesion and for monitoring the response to surgical treatment during the follow-up. The data were evaluated about medical history, physical examination findings, laboratory tests (serum urea and creatinine, blood sugar, sodium, potassium, bicarbonate levels, serum pH, uric acid, haematocrit, white blood cell count), imaging methods (renal ultrasound, abdominal CT-scan, MRI). At admission all patients had active disease with obstructive renal failure and underwent bilateral ureteric stenting in order to normalize the BUN levels. After normalizing of BUN levels, ureterolysis and omental wrapping was performed. Postoperatively, ureteric stents were removed after 1 month and remission of renal disfunction was obtained in approximately 5 months (range 2-10 months). All patients were followed for at least 1 year. Patients were regularly checked every 3 months. RESULTS: Of the 19 patients, there were 5 men and 14 women. The median age at diagnosis of RF was 50 years (range 42-64 years). The most frequent presenting symptoms were back or abdominal pain, weakness, weight loss, oligoanuria, arterial hypertension and mild fever. The duration of symptoms before diagnosis ranged from 6 to 18 months. At presentation all patients had active disease, presenting renal dysfunction with a median serum creatinine of 5.18 mg/dl (range 1-15.4 mg/dl). Most of the patients had moderate bilateral hydronephrosis (2nd degree hydronephrosis). In our study, all patients had excellent prognosis, with full recovery of renal function in 78% of cases (15 patients). The fractal dimension of the fibrosis mass contour correlates with level of renal function impairment. Even more, the fractal dimension seems to slightly variate between CT evaluations (1.30 +/- 0.1), suggesting a non aggressive pattern of extension of the fibrotic mass characteristic for benign lesions. CONCLUSIONS: The imaging parameters did not predict the disease severity, except the increase in fractal dimension of fibrosis surface area. Efficacy of bilateral ureteric stenting in improving renal function is limited in most of the cases. Dispite the level of renal function impairment at admission, full recovery can be achieved after bilateral ureteric stenting/nephrostomy and ureterolisis.


Asunto(s)
Fibrosis Retroperitoneal/terapia , Adulto , Femenino , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Pronóstico , Fibrosis Retroperitoneal/diagnóstico , Fibrosis Retroperitoneal/fisiopatología
13.
J Neurol Neurosurg Psychiatry ; 79(4): 401-6, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17635970

RESUMEN

BACKGROUND: Motor dysfunction in the contralateral hand has been well characterised after stroke. The ipsilateral hand has received less attention, yet may provide valuable insights into the structure of the motor system and the nature of the recovery process. By tracking motor function of both hands beginning in the acute stroke period in patients with cortical versus subcortical lesions, we sought to understand the functional anatomy of the ipsilateral deficit. METHODS: We examined 30 patients with first-ever unilateral hemiparetic stroke, 23 with subcortical lesions affecting the corticospinal tract, seven with cortical involvement. Patients performed hand dynamometry and the 9-Hole Peg Test (9HPT) with each hand at 24-48 h, 1 week, 3 months and 1 year after stroke. Linear regression was used to compare the two different motor tasks in each hand. Repeated measures ANOVA was used to compare recovery rates of the two tasks in the first 3 months. RESULTS: Ipsilateral 9HPT scores averaged z = -7.1, -3.6, -2.5 and -2.3 at the four time points whereas grip strength was unaffected. The initial degree of impairment of grip strength in the contralateral hand did not correlate with the degree of impairment of 9HPT in either the contralateral or ipsilateral hand (r = 0.001, p = 0.98), whereas the initial degree of impairment of 9HPT in the contralateral hand correlated with the degree of impairment of 9HPT in the ipsilateral hand (r = 0.79, p = 0.035). The rate of recovery also differed for the two tasks (p = 0.005). CONCLUSION: Ipsilateral motor deficits are demonstrable immediately after stroke and extend into the subacute and chronic recovery period. Dissociation between grip strength and dexterity support the notion that dexterity and grip strength operate as anatomically and functionally distinct entities. Our findings in patients with subcortical lesions suggest that the model of white matter tract injury needs to be refined to reflect the influence of a subcortical lesion on bi-hemispheral cortical networks, rather than as a simple "severed cable" model of disruption of corticofugal fibres. Our data have implications for both stroke clinical trials and the development of new strategies for therapeutic intervention in stroke recovery.


Asunto(s)
Infarto Cerebral/fisiopatología , Dominancia Cerebral/fisiología , Mano/inervación , Hemiplejía/fisiopatología , Destreza Motora/fisiología , Examen Neurológico , Adulto , Anciano , Corteza Cerebral/fisiopatología , Infarto Cerebral/diagnóstico , Evaluación de la Discapacidad , Femenino , Fuerza de la Mano/fisiología , Hemiplejía/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tractos Piramidales/fisiopatología
14.
J Neurol Neurosurg Psychiatry ; 79(5): 530-4, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17846113

RESUMEN

BACKGROUND: Predicting aphasia recovery after stroke has been difficult due to substantial variability in outcomes. Few studies have characterised the nature and extent of recovery, beginning with baselines at 24-72 hours after stroke onset. AIM: To characterise the course of language recovery after first-time stroke. METHODS: Using our Performance and Recovery in Stroke Study (PARIS) database, we evaluated consecutive first-time stroke patients with aphasia and diffusion-weighted-image-positive lesions on admission and at 90 days. RESULTS: Twenty-two of 91 patients had language disorders. Initial syndrome scores were positively correlated with 90-day scores (r = 0.60) and negatively correlated with the change in score from baseline to follow-up (r = -0.66). Neither lesion size, age nor education correlated with initial syndrome severity or with performance at 90 days. Level of education was not associated with degree of recovery. A multiple regression model that combined lesion size, age and initial syndrome was significant (p = 0.03) but only explained 29% of the variance. Patients with severe deficits at baseline in individual language domains could recover, improve to a less severe deficit or not improve at all. CONCLUSION: There was significant variability in language recovery after first-time stroke, even in more severe, initial syndromes. Traditional predictors of post-stroke language outcomes did not reliably predict function at 90 days. These data suggest that other factors that account for functional stroke recovery have not yet been identified.


Asunto(s)
Afasia/diagnóstico , Imagen de Difusión por Resonancia Magnética , Pruebas Neuropsicológicas , Accidente Cerebrovascular/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Anomia/diagnóstico , Comprensión , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de la Producción del Habla , Accidente Cerebrovascular/diagnóstico
15.
Neuroscience ; 134(3): 1033-45, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15979241

RESUMEN

Auditory cortex neurons integrate information over a broad range of sound frequencies, yet it is not known how such integration is accomplished at the cellular or systems levels. Whereas information about frequencies near a neuron's characteristic frequency is likely to be relayed to the neuron by lemniscal thalamocortical inputs from the ventral division of the medial geniculate nucleus, we recently proposed that information about frequencies spectrally distant from characteristic frequency is mainly relayed to the neuron via "horizontal" intracortical projections from neurons with spectrally-distant characteristic frequencies [J Neurophysiol 91 (2004) 2551]. Here we test this hypothesis by using current source density analysis to determine if characteristic frequency and spectrally-distant non-characteristic frequency stimuli preferentially activate thalamocortical and horizontal pathways, respectively, in rat auditory cortex. Characteristic frequency stimuli produced current source density profiles with prominent initial current sinks in layers 3 and 4--the termination zone of lemniscal inputs from medial geniculate nucleus. In contrast, stimuli three octaves below characteristic frequency produced initial current sinks mainly in the infragranular layers. Differences between current source density profiles were only apparent for initial current sinks; profiles for longer-latency current sinks evoked by characteristic frequency and non-characteristic frequency stimuli overlapped to a greater degree, likely due to shared mechanisms of intracortical processing or to longer-latency thalamocortical contributions (lemniscal and nonlemniscal). To identify current source density profiles produced by activation of lemniscal thalamocortical inputs alone, we utilized the mouse auditory thalamocortical slice preparation. Electrical stimulation of the medial geniculate nucleus in vitro produced major current sinks in cortical layers 3/4, and excitation spread horizontally from this point throughout primary auditory cortex to produce current sinks in multiple cortical layers. These data support the hypothesis that relay of thalamocortical information throughout auditory cortex via horizontal intracortical projections may be the basis of broad spectral integration in vivo.


Asunto(s)
Vías Aferentes/fisiología , Corteza Auditiva/citología , Potenciales Evocados/fisiología , Neuronas/fisiología , Análisis Espectral , Estimulación Acústica/métodos , Análisis de Varianza , Animales , Relación Dosis-Respuesta en la Radiación , Estimulación Eléctrica/métodos , Potenciales Evocados/efectos de la radiación , Inmunohistoquímica/métodos , Técnicas In Vitro , Masculino , Parvalbúminas/metabolismo , Ratas , Ratas Sprague-Dawley
16.
Acta Paediatr ; 93(5): 589-91, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15174777

RESUMEN

AIM: To outline some of the major ethical problems related to multiple authorship. METHODS: A survey of the literature, data collected over the years, regarding multiple authors, e.g., definition, contribution, ethical behavior and guidelines, and personal experience were the primary inputs. RESULTS: Despite the efforts of a number of editors' organizations, there still is a major problem in the attribution of authors' credits to those who had nothing to do with the writing. CONCLUSIONS: The solution to this problem may be found in one of two ways: strict enforcement of standards of authorship by journal editors, i.e., rejection of articles, no matter how good they may appear to be, because they violate these standards, and/or adoption of authorship standards as understood by commercial publishers.


Asunto(s)
Autoria , Publicaciones Periódicas como Asunto/ética , Guías como Asunto , Humanos , Edición/ética
17.
Arch Environ Contam Toxicol ; 43(4): 497-504, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12399923

RESUMEN

The elimination rate constants (k(2)) of nine polycyclic aromatic hydrocarbons (PAHs) were examined for the freshwater mussel Elliptio complanata. The concentrations of fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[ a]anthracene, chrysene, benzo[ b]fluoranthene, and indeno[1,2,3-c,d]pyrene revealed a significant inverse relationship with time and their k(2) values ranged from 0.10 to 0.22 day(-1). The k(2) values of these significantly cleared PAHs were similar to k(2) values observed for nonmetabolized organochlorines in mussels previously reported in the literature. The inverse relationship between k(2) and K(ow) provides evidence that the nine PAHs were being passively eliminated from the mussels and that they can be used to calibrate the mussel as a quantitative biomonitor. A general expression relating elimination rate constants and chemical K(ow) is derived for hydrophobic contaminants in E. complanata. The k(2) versus log K(ow) regression equation for mussels developed herein was similar to other studies documenting the elimination of PCBs and PAHs in a number of bivalve species.


Asunto(s)
Bivalvos , Monitoreo del Ambiente/métodos , Hidrocarburos Policíclicos Aromáticos/farmacocinética , Contaminantes Químicos del Agua/farmacocinética , Animales , Calibración , Hidrocarburos Policíclicos Aromáticos/análisis , Análisis de Regresión , Contaminantes Químicos del Agua/análisis
18.
Am J Psychoanal ; 61(3): 271-91, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11605231

RESUMEN

In this article, the author traces the history of the concepts of subject, subjectivity, and intersubjectivity in different psychoanalytic theories in the last decades. She argues that the uniqueness of these concepts and their different implications were not emphasized enough. The author discusses the various implications and contexts of the concept of subject in psychoanalytic theory proper and to relate as to: (1). The need to distinguish between the concepts of subject and subjectivity; (2). The mutual interdependence of the subject and his subjectivity and the intersubjective domain (both in the development of the individual and in theoretical thought pertaining to it). Her point of departure is from the position of the subject as a free creature, the centrality of the experiencing individual, from his/her perspective--the subject in the first person. She tries to explain the paradox implicit in the experiential dimension, the place of the other as participant, as both negating and recognizing--the subject in the third person. She suggests the interdependency of the first-person experience of subjectivity on the intersubjective dimension.


Asunto(s)
Apego a Objetos , Percepción Social , Cognición , Humanos , Teoría Psicoanalítica , Autoimagen
19.
Brain ; 124(Pt 6): 1208-17, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11353736

RESUMEN

We used the setting of clinically indicated internal carotid artery balloon test occlusions in 44 patients with inoperable carotid cavernous aneurysms or head and neck tumours to examine real-time changes in higher cerebral function that correlate with specific levels of cerebral blood flow. By making detailed haemodynamic and neurobehavioural measurements during the 30 min the carotid artery was occluded, we were able to quantify higher cerebral function patterns in relation to absolute cerebral blood flow (CBF) levels. We found that once the carotid artery was occluded, patients whose CBF averaged 47 ml/100 g/min (no different from baseline) maintained consistent performance on a sustained attention task; those whose CBF dropped to an average 37 ml/100 g/min had a reversible deterioration of sustained attention, and those whose CBF fell to 27 ml/100 g/min had impaired sustained attention that persisted until the carotid occlusion was reversed. The relevance of these results to the pathological state of clinical stroke is discussed with respect to the haemodynamic and physiological mechanisms that may determine how brain function is lost and regained in the setting of acute cerebral hypoperfusion.


Asunto(s)
Trombosis de las Arterias Carótidas/complicaciones , Corteza Cerebral/fisiopatología , Circulación Cerebrovascular/fisiología , Ataque Isquémico Transitorio/fisiopatología , Recuperación de la Función/fisiología , Atención/fisiología , Oclusión con Balón/efectos adversos , Trombosis de las Arterias Carótidas/patología , Trombosis de las Arterias Carótidas/fisiopatología , Corteza Cerebral/patología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/patología , Trastornos del Conocimiento/fisiopatología , Femenino , Humanos , Ataque Isquémico Transitorio/etiología , Ataque Isquémico Transitorio/patología , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología , Radioisótopos de Xenón
20.
Neurosurg Focus ; 11(5): e4, 2001 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-16466236

RESUMEN

Arteriovenous malformations (AVMs) of the brain, thought to begin during fetal development and undergo an unclear maturation process; most often do not become symptomatic until the patient reaches adulthood. Authors of recent prospective studies have suggested that relatively few patients present with neuropsychological abnormalities in the absence of hemorrhage. In general, neuropsychological evaluations in patients with AVMs have yielded mixed results with respect to localization of function, and the authors of most cognitive studies have not been able to demonstrate the nature and degree of impairment seen in acute ischemic stroke in comparable brain regions. Superselective Wada testing prior to therapeutic embolization, functional imaging studies, and intrasurgical cortical mapping have shown redistribution of language and memory to unpredictable regions. Developmental cognitive history in these patients indicates that most will have at least some background of learning problems during the school-age years with varying degrees of severity, reflecting a time when brain reorganization may be occurring. These data suggest that traditional assumptions about the eloquence of brain regions may not hold for patients with AVMs and that establishing treatment risk in the individual patient needs to be made on an empirical basis.


Asunto(s)
Amobarbital , Mapeo Encefálico/métodos , Trastornos del Conocimiento/etiología , Malformaciones Arteriovenosas Intracraneales/complicaciones , Amobarbital/administración & dosificación , Arterias Cerebrales , Hemorragia Cerebral/etiología , Hemorragia Cerebral/psicología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/prevención & control , Terapia Combinada , Dominancia Cerebral , Embolización Terapéutica , Humanos , Inyecciones Intraarteriales , Malformaciones Arteriovenosas Intracraneales/fisiopatología , Malformaciones Arteriovenosas Intracraneales/psicología , Malformaciones Arteriovenosas Intracraneales/cirugía , Malformaciones Arteriovenosas Intracraneales/terapia , Imagen por Resonancia Magnética , Magnetoencefalografía , Pruebas Neuropsicológicas , Cuidados Preoperatorios
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