COVID-19 vaccines reduce mortality in hospitalized patients with oxygen requirements: Differences between vaccine subtypes. A multicontinental cohort study.

The aim of this study was to analyze whether the coronavirus disease 2019 (COVID-19) vaccine reduces mortality in patients with moderate or severe COVID-19 disease requiring oxygen therapy. A retrospective cohort study, with data from 148 hospitals in both Spain (111 hospitals) and Argentina (37 hospitals), was conducted. We evaluated hospitalized patients for COVID-19 older than 18 years with oxygen requirements. Vaccine protection against death was assessed through a multivariable logistic regression and propensity score matching. We also performed a subgroup analysis according to vaccine type. The adjusted model was used to determine the population attributable risk. Between January 2020 and May 2022, we evaluated 21,479 COVID-19 hospitalized patients with oxygen requirements. Of these, 338 (1.5%) patients received a single dose of the COVID-19 vaccine and 379 (1.8%) were fully vaccinated. In vaccinated patients, mortality was 20.9% (95% confidence interval [CI]: 17.9-24), compared to 19.5% (95% CI: 19-20) in unvaccinated patients, resulting in a crude odds ratio (OR) of 1.07 (95% CI: 0.89-1.29; p = 0.41). However, after considering the multiple comorbidities in the vaccinated group, the adjusted OR was 0.73 (95% CI: 0.56-0.95; p = 0.02) with a population attributable risk reduction of 4.3% (95% CI: 1-5). The higher risk reduction for mortality was with messenger RNA (mRNA) BNT162b2 (Pfizer) (OR 0.37; 95% CI: 0.23-0.59; p < 0.01), ChAdOx1 nCoV-19 (AstraZeneca) (OR 0.42; 95% CI: 0.20-0.86; p = 0.02), and mRNA-1273 (Moderna) (OR 0.68; 95% CI: 0.41-1.12; p = 0.13), and lower with Gam-COVID-Vac (Sputnik) (OR 0.93; 95% CI: 0.6-1.45; p = 0.76). COVID-19 vaccines significantly reduce the probability of death in patients suffering from a moderate or severe disease (oxygen therapy).

Self-gated fat-suppressed cardiac cine MRI.

PURPOSE: To develop a self-gated alternating repetition time balanced steady-state free precession (ATR-SSFP) pulse sequence for fat-suppressed cardiac cine imaging. METHODS: Cardiac gating is computed retrospectively using acquired magnetic resonance self-gating data, enabling cine imaging without the need for electrocardiogram (ECG) gating. Modification of the slice-select rephasing gradients of an ATR-SSFP sequence enables the acquisition of a one-dimensional self-gating readout during the unused short repetition time (TR). Self-gating readouts are acquired during every TR of segmented, breath-held cardiac scans. A template-matching algorithm is designed to compute cardiac trigger points from the self-gating signals, and these trigger points are used for retrospective cine reconstruction. The proposed approach is compared with ECG-gated ATR-SSFP and balanced steady-state free precession in 10 volunteers and five patients. RESULTS: The difference of ECG and self-gating trigger times has a variability of 13 ± 11 ms (mean ± SD). Qualitative reviewer scoring and ranking indicate no statistically significant differences (P > 0.05) between self-gated and ECG-gated ATR-SSFP images. Quantitative blood-myocardial border sharpness is not significantly different among self-gated ATR-SSFP ( 0.61±0.15 mm -1), ECG-gated ATR-SSFP ( 0.61±0.15 mm -1), or conventional ECG-gated balanced steady-state free precession cine MRI ( 0.59±0.15 mm -1). CONCLUSION: The proposed self-gated ATR-SSFP sequence enables fat-suppressed cardiac cine imaging at 1.5 T without the need for ECG gating and without decreasing the imaging efficiency of ATR-SSFP.

Respiration based steering for high intensity focused ultrasound liver ablation.

PURPOSE: Respiratory motion makes hepatic ablation using high intensity focused ultrasound (HIFO) challenging. Previous HIFU liver treatment had required apnea induced during general anesthesia. We describe and test a system that allows treatment of the liver in the presence of breathing motion. METHODS: Mapping a signal from an external respiratory bellow to treatment locations within the liver allows the ultrasound transducer to be steered in real time to the target location. Using a moving phantom, three metrics were used to compare static, steered, and unsteered sonications: the area of sonications once a temperature rise of 15°C was achieved, the energy deposition required to reach that temperature, and the average rate of temperature rise during the first 10 s of sonication. Steered HIFU in vivo ablations of the porcine liver were also performed and compared to breath-hold ablations. RESULTS: For the last phantom metric, all groups were found to be statistically significantly different (P ≤ 0.003). However, in the other two metrics, the static and unsteered sonications were not statistically different (P > 0.9999). Steered in vivo HIFU ablations were not statistically significantly different from ablations during breath-holding. CONCLUSIONS: A system for performing HIFU steering during ablation of the liver with breathing motion is presented and shown to achieve results equivalent to ablation performed with breath-holding.

Occipital cortex activation by long-term repetitive tactile stimulation is necessary for object recognition in blinds: a case report.

Tactile vision has been approached from a variety of angles using different techniques. So far, a certain kind of object (and text) recognition has been shown, though seeing as such has not been achieved yet, and it remains unclear. Trough repetitive passive tactile stimulation perceptual processing is transferred from temporo-parietal to occipital areas, which affects object recognition. We report the results of passive tactile stimulation, as well as rTMS, applied to a 50 year old left handed blind male with over 97% loss of vision, who suffers from Peter's anomaly and microphthalmia. After 15 weeks of passive tactile stimulation, the subject showed increased activity in occipital areas associated with the development of visual-like perception which remained unchanged after three months without passive tactile stimulation. Inhibitory rTMS over the visual cortex led to noticeable reduction of spatial recognition performance and visual sensations in this subject. Stable changes in occipital cortical activity can be associated with subjective sensations of seeing. Once occipital activation has been achieved, it is necessary for spatial object recognition. Both facts highlight the implication of occipital areas in tactile vision and the cortical plasticity of passive tactile long-term stimulation in people with blindness.

Three-dimensional first-pass myocardial perfusion MRI using a stack-of-spirals acquisition.

Three-dimensional cardiac magnetic resonance perfusion imaging is promising for the precise sizing of defects and for providing high perfusion contrast, but remains an experimental approach primarily due to the need for large-dimensional encoding, which, for traditional 3DFT imaging, requires either impractical acceleration factors or sacrifices in spatial resolution. We demonstrated the feasibility of rapid three-dimensional cardiac magnetic resonance perfusion imaging using a stack-of-spirals acquisition accelerated by non-Cartesian k-t SENSE, which enables entire myocardial coverage with an in-plane resolution of 2.4 mm. The optimal undersampling pattern was used to achieve the largest separation between true and aliased signals, which is a prerequisite for k-t SENSE reconstruction. Flip angle and saturation recovery time were chosen to ensure negligible magnetization variation during the transient data acquisition. We compared the proposed three-dimensional perfusion method with the standard 2DFT approach by consecutively acquiring both data during each R-R interval in cardiac patients. The mean and standard deviation of the correlation coefficients between time intensity curves of three-dimensional versus 2DFT were 0.94 and 0.06 across seven subjects. The linear correlation between the two sets of upslope values was significant (r = 0.78, P < 0.05).

Reducing artifacts in one-dimensional Fourier velocity encoding for fast and pulsatile flow.

When evaluating the severity of valvular stenosis, the peak velocity of the blood flow is routinely used to estimate the transvalvular pressure gradient. One-dimensional Fourier velocity encoding effectively detects the peak velocity with an ungated time series of spatially resolved velocity spectra in real time. However, measurement accuracy can be degraded by the pulsatile and turbulent nature of stenotic flow and the existence of spatially varying off-resonance. In this work, we investigate the feasibility of improving the peak velocity detection capability of one-dimensional Fourier velocity encoding for stenotic flow using a novel echo-shifted interleaved readout combined with a variable-density circular k-space trajectory. The shorter echo and readout times of the echo-shifted interleaved acquisitions are designed to reduce sensitivity to off-resonance. Preliminary results from limited phantom and in vivo results also indicate that some artifacts from pulsatile flow appear to be suppressed when using this trajectory compared to conventional single-shot readouts, suggesting that peak velocity detection may be improved. The efficiency of the new trajectory improves the temporal and spatial resolutions. To realize the proposed readout, a novel multipoint-traversing algorithm is introduced for flexible and automated gradient-waveform design.

Initial accuracy of bedside ultrasound performed by emergency physicians for multiple indications after a short training period.

PURPOSES: Emergency physician-performed ultrasonography holds promise as a rapid and accurate method to diagnose multiple diseases in the emergency department (ED). Our objective was to assess the initial diagnostic accuracy (first 55 explorations) of emergency physician-performed ultrasonography for multiple categories of ultrasound use after a short training period. BASIC PROCEDURES: This was a prospective observational study conducted at an urban ED from June 2010 to March 2011 in patients with suspected cholecystitis, hydronephrosis, deep vein thrombosis, and different cardiovascular problems. Five physicians had a 10-hour training session before enrolling patients. The test characteristics of bedside ultrasonography were determined with the final radiologist/cardiologist interpretation. MAIN FINDINGS: A total of 275 ultrasonographic examinations were performed (78 abdominal explorations, 80 renal explorations, 76 2-point compression ultrasonographic examinations in patients with suspected deep vein thrombosis, and 41 echocardiograms in patients with different acute cardiovascular problems). Radiologists/cardiologists detected 28 cases of cholecystitis, 26 cases of deep vein thrombosis, 49 cases of hydronephrosis, and 15 cases of significant cardiovascular alterations. The overall diagnostic accuracy of ED ultrasonograms yielded a sensitivity, specificity, positive predictive value, and negative predictive value of 92.6% (95% confidence interval [CI], 90%-99%), 89% (95% CI, 84%-94%), 86.2 % (95% CI, 82%-93%), and 94.2% (95% CI, 92%-99%), respectively. Nineteen (6.9%) false-positive results and 6 false-negative results (2.1%) were obtained. PRINCIPAL CONCLUSIONS: Emergency physicians in our institution attained reasonably high initial accuracy in the performance of ultrasonography for a variety of clinical problems after a 10-hour training period.

Fast concomitant gradient field and field inhomogeneity correction for spiral cardiac imaging.

Non-Cartesian imaging provides many advantages in terms of flexibility, functionality, and speed. However, a major drawback to these imaging methods is off-resonance distortion artifacts. These artifacts manifest as blurring in spiral imaging. Common techniques that remove the off-resonance field inhomogeneity distortion effects are not sufficient, because the high order concomitant gradient fields are nontrivial for common imaging conditions, such as imaging 5 cm off isocenter in an 1.5 T scanner. Previous correction algorithms are either slow or do not take into account the known effects of concomitant gradient fields along with the field inhomogeneities. To ease the correction, the distortion effects are modeled as a non-stationary convolution problem. In this work, two fast and accurate postgridding algorithms are presented and analyzed. These methods account for both the concomitant field effects and the field inhomogeneities. One algorithm operates in the frequency domain and the other in the spatial domain. To take advantage of their speed and accuracy, the algorithms are applied to a real-time cardiac study and a high-resolution cardiac study. Both of the presented algorithms provide for a practical solution to the off-resonance problem in spiral imaging.

Real-time motion correction for high-resolution larynx imaging.

Motion--both rigid-body and nonrigid--is the main limitation to in vivo, high-resolution larynx imaging. In this work, a new real-time motion compensation algorithm is introduced. Navigator data are processed in real time to compute the displacement information, and projections are corrected using phase modulation in k-space. Upon automatic feedback, the system immediately reacquires the data most heavily corrupted by nonrigid motion, i.e., the data whose corresponding projections could not be properly corrected. This algorithm overcomes the shortcomings of the so-called diminishing variance algorithm by combining it with navigator-based rigid-body motion correction. Because rigid-body motion correction is performed first, continual bulk motion no longer impedes nor prevents the convergence of the algorithm. Phantom experiments show that the algorithm properly corrects for translations and reacquires data corrupted by nonrigid motion. Larynx imaging was performed on healthy volunteers, and substantial reduction of motion artifacts caused by bulk shift, swallowing, and coughing was achieved.

In vivo MR acoustic radiation force imaging in the porcine liver.

PURPOSE: High intensity focused ultrasound (HIFU) in the abdomen can be sensitive to acoustic aberrations that can exist in the beam path of a single sonication. Having an accurate method to quickly visualize the transducer focus without damaging tissue could assist with executing the treatment plan accurately and predicting these changes and obstacles. By identifying these obstacles, MR acoustic radiation force imaging (MR-ARFI) provides a reliable method for visualizing the transducer focus quickly without damaging tissue and allows accurate execution of the treatment plan. METHODS: MR-ARFI was used to view the HIFU focus, using a gated spin echo flyback readout-segmented echo-planar imaging sequence. HIFU spots in a phantom and in the livers of five live pigs under general anesthesia were created with a 550 kHz extracorporeal phased array transducer initially localized with a phase-dithered MR-tracking sequence to locate microcoils embedded in the transducer. MR-ARFI spots were visualized, observing the change of focal displacement and ease of steering. Finally, MR-ARFI was implemented as the principle liver HIFU calibration system, and MR-ARFI measurements of the focal location relative to the thermal ablation location in breath-hold and breathing experiments were performed. RESULTS: Measuring focal displacement with MR-ARFI was achieved in the phantom and in vivo liver. In one in vivo experiment, where MR-ARFI images were acquired repeatedly at the same location with different powers, the displacement had a linear relationship with power [y = 0.04x + 0.83 µm (R(2) = 0.96)]. In another experiment, the displacement images depicted the electronic steering of the focus inside the liver. With the new calibration system, the target focal location before thermal ablation was successfully verified. The entire calibration protocol delivered 20.2 J of energy to the animal (compared to greater than 800 J for a test thermal ablation). ARFI displacement maps were compared with thermal ablations during seven breath-hold ablations. The error was 0.83 ± 0.38 mm in the S/I direction and 0.99 ± 0.45 mm in the L/R direction. For six spots in breathing ablations, the mean error in the nonrespiration direction was 1.02 ± 0.89 mm. CONCLUSIONS: MR-ARFI has the potential to improve free-breathing plan execution accuracy compared to current calibration and acoustic beam adjustment practices. Gating the acquisition allows for visualization of the focal spot over the course of respiratory motion, while also being insensitive to motion effects that can complicate a thermal test spot. That MR-ARFI measures a mechanical property at the focus also makes it insensitive to high perfusion, of particular importance to highly perfused organs such as the liver.

Real-time MR thermometry for monitoring HIFU ablations of the liver.

A high-resolution and high-speed pulse sequence is presented for monitoring high-intensity focused ultrasound ablations in the liver in the presence of motion. The sequence utilizes polynomial-order phase saturation bands to perform outer volume suppression, followed by spatial-spectral excitation and three readout segmented echo-planar imaging interleaves. Images are processed with referenceless thermometry to create temperature-rise images every frame. The sequence and reconstruction were implemented in RTHawk and used to image stationary and moving sonications in a polyacrylamide gel phantom (62.4 acoustic W, 50 sec, 550 kHz). Temperature-rise images were compared between moving and stationary experiments. Heating spots and corresponding temperature-rise plots matched very well. The stationary sonication had a temperature standard deviation of 0.15 degrees C compared to values of 0.28 degrees C and 0.43 degrees C measured for two manually moved sonications at different velocities. Moving the phantom (while not heating) with respect to the transducer did not cause false temperature rises, despite susceptibility changes. The system was tested on nonheated livers of five normal volunteers. The mean temperature rise was -0.05 degrees C, with a standard deviation of 1.48 degrees C. This standard deviation is acceptable for monitoring high-intensity focused ultrasound ablations, suggesting real-time imaging of moving high-intensity focused ultrasound sonications can be clinically possible.

[Translation and cultural adaptation of the Exercise Fear Avoidance Scale for Chilean older adults]. / Traducción y adaptación cultural del cuestionario Exercise Fear Avoidance Scale para su uso en adultos mayores chilenos.

OBJECTIVE: To translate and culturally adapt the Exercise Fear Avoidance Scale (EFAS) Into Spanish for Chilean older adults. MATERIALS AND METHODS: Double direct translation with harmonization, back translation and analysis of text comprehensibility through cognitive interviews. A sample of 20 older adults between the ages of 63 and 83 participated in the cognitive interview process. RESULTS: All items were assessed as clear and understandable. Using the paraphrasing and inquiry techniques, 3 items (out of 16) were adapted to achieve better understanding. Two of these adaptations consisted in replacing one concept with another, as the latter was more used in the Chilean context, and making a non-literal translation, since the literal one was too complex for the elderly to understand. CONCLUSIONS: A Spanish version of the EFAS was obtained, which proved to be understandable and adapted for its use with Chilean older adults.

OBJETIVO: Traducir y adaptar culturalmente el cuestionario Exercise Fear Avoidance Scale (EFAS) al español para su uso en adultos mayores chilenos. MATERIALES Y MÉTODOS: Doble traducción directa con armonización de versiones, retro-traducción y análisis de la comprensibilidad mediante entrevistas cognitivas. En el proceso de entrevistas cognitivas participaron 20 adultos mayores con edades comprendidas entre 63 y 83 años. RESULTADOS: Todos los ítems fueron evaluados como claros y comprensibles. Mediante la técnica de parafraseo e indagación 3 ítems (de un total de 16) se tuvieron que adaptar para lograr una mejor comprensión. Dos de estas adaptaciones consistieron en reemplazar un concepto por uno más utilizado en el contexto chileno y otra modificación fue en relación con la redacción, puesto que su lectura resultaba compleja para esta población. CONCLUSIONES: Se obtuvo una versión en español del cuestionario EFAS, la cual demostró ser comprensible y adaptada para su uso en adultos mayores chilenos.

Adverse psychiatric effects of antiepileptic drugs.

Psychiatric symptoms provide potential insights into the pathophysiology of psychiatric conditions in epilepsy patients. Evaluating the psychiatric effects of newer AEDs is complicated by several important factors including (a) the relatively high rate of mood and anxiety disorders in persons with pharmacoresistant epilepsy, and (b) the variety of methods used to assess the occurrence and severity of psychiatric symptoms. Clinical trials to assess adverse psychiatric effects of AEDs need a control group to adjust for the spontaneous occurrence of symptoms, as well as to demonstrate potential positive psychotropic effects. The follow-up should be long enough to differentiate between drug-related effects and the natural course of the comorbid disorder. Psychiatric problems should be defined using appropriate instruments as well as self-report.

[Variation in mortality inequalities in the autonomous communities of Spain: a matter of mortality in people with less education].

BACKGROUND: Given the importance of mortality rates in each socioeconomic group, as explanation for the variation in mortality inequalities across populations, the objective of the present study is to evaluate whether regional variation in mortality inequalities in Spain is related to the mortality rates in different socioeconomic groups. METHODS: The study included all persons aged 30-74 years living in Spain in 2001 and followed up for mortality over 7 years. In each of the 17 autonomous communities of Spain mortality rates were estimated for those with low and high education, as well as two measures of mortality inequality according to education: mortality rate difference and mortality rate ratio. Median value of mortality inequalities was calculated for the regions with the highest and lowest mortality rates and for those with intermediate mortality rates. And the Pearson correlation coefficient was used to estimate the relation between mortality rates and the measures of mortality inequality. RESULTS: The correlation coefficients between mortality rate in low education and mortality rate difference and mortality rate ratio were 0.87 and 0.78 in women and 0.81 and 0.73 in men, respectively. The correlation coefficients between mortality rate in high education and mortality rate difference and mortality rate ratio were -0.07 and -0.24 in women and 0.10 and -0.06 in men, respectively. CONCLUSION: Regions with the lowest and highest mortality rates in low education people generally had the lowest and highest inequalities in mortality. The variation in the magnitude of inequalities in mortality from one place to another can be explained by the variation in mortality in low education people. No relation was observed between mortality rate in high education and mortality inequality.

[Inequalities in Total Mortality and by Cause of Death According to the Level of Education in Navarra: findings from a Longitudinal Study from 2001 to 2008]. / Desigualdades en mortalidad total y por causa de muerte según el nivel de estudios en Navarra: hallazgos de un estudio longitudinal 2001-2008.

BACKGROUND: Due to the lack of evidence, the objective was to show the inequalities in mortality by educational level in Navarra and the contribution of the main causes of death to the magnitude of inequalities in mortality from all causes of death. METHODS: All citizens aged 25 years and older residing in Spain in 2001 were followed during 7 years to determine their vital status. Level of education was used as socioeconomic status indicator. It was estimated the age-adjusted total mortality rate and mortality rate from cause-specific mortality by educational level. Then it was calculated the relative difference (ratio) and the absolute difference in rates between the lowest and highest levels of education and the contribution of the main causes of death to the absolute difference. RESULTS: The rate ratio for all causes of death was 1.37 in men and 1.23 in women. The human immunodeficiency virus (HIV) (25.84) and unintentional injuries (3.78) are the causes of death with higher rate ratio in men and diabetes (4.92) and HIV (4.38) in women. Cardiovascular diseases were the leading causes of death that contribute most to the absolute difference in mortality: 26% in men and 48% women. CONCLUSIONS: The mortality rate in the Navarre population shows an inverse gradient with educational level, except in some cancer sites. Cardiovascular disease is the leading cause of death that contributes most to the absolute inequalities in mortality, while other causes of death that show significant relative inequalities, contribute little to the absolute inequalities.

Impact of atypical antipsychotics on quality of life, self-report of symptom severity, and demand of services in chronically psychotic patients.

OBJECTIVE: The study investigated whether the introduction of atypical neuroleptics in the formulary of a large community mental health clinic had any impact on demand for services, quality of life, symptom presentation and cost of care of patients with chronic psychotic illnesses over a 3-year period. METHODS: BJC Behavioral Health Services provides and coordinates mental health services for citizens residing in St. Louis City, St. Louis County and the counties of St. Francois, Iron and Washington, MO. We searched the BJC Behavioral Health Services and the Missouri Pharmacy Database to identify patients who had been switched from a typical to an atypical neuroleptic for a minimum of 3 months between 5/1/1997 and 4/30/2000. We excluded patients treated with more than one neuroleptic simultaneously and those with incomplete records. The primary outcome measures were: level of care assignment. Secondary outcomes were a quality of life scale, and a symptom severity inventory. Twenty-five patients met final entry criteria (out of a census of 6280 patients on 3/6/2000). RESULTS: In this naturalistic sample of patients with chronic severe psychotic symptoms, atypical neuroleptic treatment resulted in a marked reduction in demand of services, marked improvement on perception of quality of life, and a trend towards reduction in symptom severity, particularly in the cluster of affective symptoms of the SLSS, over a 3-year period. We also found that the cost of care after switching to atypical neuroleptics was increased, which coincided with increased number of services provided to the patients. These changes appeared to be the result of improved compliance with outpatient services such as follow-up visits and rehabilitative activities.

Traducción y adaptación cultural del cuestionario exercise fear avoidance scale para su uso en adultos mayores chilenos / Translation and cultural adaptation of the Exercise Fear Avoidance Scale for Chilean older adults / Tradução e adaptação cultural do questionário de escala do exercício para evitar o uso em idosos chilenos

RESUMEN Objetivo Traducir y adaptar culturalmente el cuestionario Exercise Fear Avoidance Scale (EFAS) al español para su uso en adultos mayores chilenos. Materiales y Métodos Doble traducción directa con armonización de versiones, retro-traducción y análisis de la comprensibilidad mediante entrevistas cognitivas. En el proceso de entrevistas cognitivas participaron 20 adultos mayores con edades comprendidas entre 63 y 83 años. Resultados Todos los ítems fueron evaluados como claros y comprensibles. Mediante la técnica de parafraseo e indagación 3 ítems (de un total de 16) se tuvieron que adaptar para lograr una mejor comprensión. Dos de estas adaptaciones consistieron en reemplazar un concepto por uno más utilizado en el contexto chileno y otra modificación fue en relación con la redacción, puesto que su lectura resultaba compleja para esta población. Conclusiones Se obtuvo una versión en español del cuestionario EFAS, la cual demostró ser comprensible y adaptada para su uso en adultos mayores chilenos.(AU)

ABSTRACT Objective To translate and culturally adapt the Exercise Fear Avoidance Scale (EFAS) Into Spanish for Chilean older adults. Materials and Methods Double direct translation with harmonization, back translation and analysis of text comprehensibility through cognitive interviews. A sample of 20 older adults between the ages of 63 and 83 participated in the cognitive interview process. Results All items were assessed as clear and understandable. Using the paraphrasing and inquiry techniques, 3 items (out of 16) were adapted to achieve better understanding. Two of these adaptations consisted in replacing one concept with another, as the latter was more used in the Chilean context, and making a non-literal translation, since the literal one was too complex for the elderly to understand. Conclusions A Spanish version of the EFAS was obtained, which proved to be understandable and adapted for its use with Chilean older adults.(AU)

OBJETIVO Traduza e adapte culturalmente o questionário da Escala de Evitação do Medo do Exercício (EFAS) ao espanhol para uso em idosos chilenos. MATERIAIS E MÉTODOS Tradução direta dupla com harmonização de versões, retrotradução e análise de compreensibilidade por meio de entrevistas cognitivas. Vinte idosos entre 63 e 83 anos participaram do processo de entrevista cognitiva. RESULTADOS Todos os itens foram avaliados como claros e compreensíveis. Usando a paráfrase e a técnica de investigação, três itens (de um total de 16) tiveram que ser adaptados para alcançar uma melhor compreensão. Duas dessas adaptações consistiram em substituir um conceito por outro mais utilizado no contexto chileno e outra modificação em relação à redação, uma vez que sua leitura era complexa para essa população. CONCLUSÕES Foi obtida uma versão em espanhol do questionário EFAS, que se mostrou compreensível e adaptado para uso em idosos chilenos.(AU)

[Is the early brain organisation of spatial information conveyed by tactile stimuli performed in different ways in congenital and acquired blind children? A pilot study]. / Es distinta la organizacion cerebral temprana de la informacion espacial transmitida a traves de estimulos tactiles en ninos invidentes congenitos y adquiridos?: un estudio piloto.

Cortical reorganization after congenital blindness is not sufficiently known yet it does offer an optimum window of opportunity to study the effects of absolute sensorial deprivation. Cross-modality in people with blindness has been documented, but it may differ in congenital blindness and in early blindness. Vibrotactile passive stimulation of lines and letters generates different electroencephalographic patterns with different source localizations in two children with blindness, aged 9 and 10, respectively with congenital blindness and early blindness with some remnants of vision. Most of the brain electrical activity is centered in auditive areas in P50 and P100 in the case of the child with congenital blindness, while the other shows activity in multiple areas. Reaction times to letters are shorter than to lines of different orientation in both children.

[Cortical organization of different languages with different proficiency levels]. / Organizacion cortical de diferentes lenguas con distintos grados de dominio.

INTRODUCTION: Several studies have enhanced differences and similarities in the processing of early and late acquired languages. Anatomic and functional differences have demonstrated how bilingualism exerts executive functions, dependent of the prefrontal cortex in the frontal lobe. AIM: To study the cortical differences, neurophysiologically measured in school-aged children, in the processing of known and unknown languages. SUBJECTS AND METHODS: We have measured the recognition processes of words in several languages, specifically Spanish, English, Portuguese and Mandarin Chinese, as well as their event-related potentials (ERP) correlates in 10 year-old children. RESULTS: The greater knowledge of a language (in our study, Spanish) associates shorter latencies in ERP and a greater activity in both early (N200) and late (N400) components of temporal regions, demonstrating both a direct relation between practice and speed of processing of the language and the consolidation of the linguistic information in the temporal lobe, while less familiar or unknown languages show longer latencies and a greater involvement of posterior brain areas, as well as a different lateralization probably due to a higher effort put on its integration, mostly in late processing stages of linguistic information, which ultimately reflects a clear effect of the neuroplasticity generated by practice, as more efficient and stable neural networks are created after being trained for a long time, in contrast with what occurs with those which have not been sufficiently stimulated. CONCLUSION: Mandarin Chinese's organization in the brain cortex shows bilateral with right dominant lateralization as well as longer ERP latencies.

Medusa: a scalable MR console using USB.

Magnetic resonance imaging (MRI) pulse sequence consoles typically employ closed proprietary hardware, software, and interfaces, making difficult any adaptation for innovative experimental technology. Yet MRI systems research is trending to higher channel count receivers, transmitters, gradient/shims, and unique interfaces for interventional applications. Customized console designs are now feasible for researchers with modern electronic components, but high data rates, synchronization, scalability, and cost present important challenges. Implementing large multichannel MR systems with efficiency and flexibility requires a scalable modular architecture. With Medusa, we propose an open system architecture using the universal serial bus (USB) for scalability, combined with distributed processing and buffering to address the high data rates and strict synchronization required by multichannel MRI. Medusa uses a modular design concept based on digital synthesizer, receiver, and gradient blocks, in conjunction with fast programmable logic for sampling and synchronization. Medusa is a form of synthetic instrument, being reconfigurable for a variety of medical/scientific instrumentation needs. The Medusa distributed architecture, scalability, and data bandwidth limits are presented, and its flexibility is demonstrated in a variety of novel MRI applications.