RESUMEN
Talocalcaneonavicular or subtalar dislocation is the simultaneous dislocation of the talar joints at the talocalcaneal and talonavicular levels. It may occur in any direction and results in foot deformity. The most common type is medial dislocation. Lateral, anterior and posterior dislocations are less common. These dislocations are associated with osteochondral fractures. Closed reduction and immobilization continue to be the cornerstones of treatment. X-rays and computerized axial tomography scan of the involved ankle and foot confirm the congruence of the subtalar joint after reduction and rule out fractures. Magnetic resonance imaging is a good alternative to assess talar vascular necrosis during the followup of these patients. The case of a medial subtalar dislocation in a 52 year-old patient is reported herein together with its diagnostic and therapeutic management and a case review from the medical literature.
Asunto(s)
Luxaciones Articulares , Articulación Talocalcánea/lesiones , Articulaciones Tarsianas/lesiones , Humanos , Luxaciones Articulares/terapia , Masculino , Persona de Mediana EdadRESUMEN
A modelagem da temperatura em tecidos humanos, quando os mesmos são sujeitos a ultra-som de terapia, é um aspecto essencial para um correto controle e calibração da instrumentação de terapia. A existência de modelos precisos possibilitaria um uso mais seguro e eficiente das terapias térmicas. O objetivo principal deste trabalho é a comparação entre a performance de um modelo linear e de um modelo não linear, na estimação pontual da temperatura num meio homogêneo. O objetivo final do trabalho é a construção de modelos para estimação in-vivo da temperatura. Os modelos lineares aplicados foram "autoregressive models with exogenous inputs" (ARX), enquanto que os modelos não-lineares aplicados foram "radial basis functions neural networks" (RBFNN). As melhores estruturas para as RBFNN foram selecionadas usando o "multi-objective genetic algoritm" (MOGA). A melhor estrutura RBFNN apresentou um erro máximo absoluto de 0,2ºC, que é inferior em uma ordem de grandeza ao erro cometido pelo melhor modelo ARX.
Asunto(s)
Terapia por Ultrasonido , Modelos Lineales , Red NerviosaRESUMEN
Temperature modeling of human tissue subjected to ultrasound for therapeutic use is essential for an accurate instrumental assessment and calibration. Prior studies with a homogeneous medium are hereby reported. Nonlinear punctual temperature modeling is proposed by means of Radial Basis Functions Neural Network (RBFNN) structures...
Asunto(s)
Algoritmos , Regulación de la Temperatura Corporal , Redes Neurales de la Computación , UltrasonografíaRESUMEN
A pooling system was developed for use in anti-HCV screening of voluntary blood donors at the local Central American Red Cross blood banks, in Nicaragua, El Salvador and Honduras. The commercially available second generation anti-HCV screening kit from Abbott Laboratories (North Chicago, IL) was used with a modification in the initial serum dilution procedure. Pools of five sera were selected for routine screening, based on comparative studies of individual samples and of pools with different sample sizes. During the years 1993 and 1994 a total of 89, 148 voluntary blood donors were screened and a positive prevalence rate of 0.35% was established. Of the initially positive samples, 54% confirmed positive, 30% were indeterminate and 16% were negative using the Abbott Matrix test. Significant differences of positive screening prevalence rates were found in the three countries, with average values of 0.50%, 0.23% and 0.08%, respectively, in Nicaragua, El Salvador and Honduras. These initially positive samples also showed a different confirmatory pattern with a positive rate of 64% in Nicaragua, in contrast to 20% in El Salvador. Only a few samples were available for RT-PCR amplification of HCV-RNA; however, this highly sensitive method did not appear to be more helpful than serology in confirming the HCV donor status. Overall, the data obtained indicate a fluctuation of HCV prevalence in voluntary blood donors among the three Central American countries. Further, differences were found in the percentages of initially screened positives and confirmation patterns. This information appears useful for establishing criteria in future screening policies. Thus, we suggest that the use of pooling for anti-HCV screening is beneficial in countries under development, since there are potential cost savings, as well as benefits in establishment of initial prevalence rates.