Microscopic fractional anisotropy outperforms multiple sclerosis lesion assessment and clinical outcome associations over standard fractional anisotropy tensor.

We aimed to compare the ability of diffusion tensor imaging and multi-compartment spherical mean technique to detect focal tissue damage and in distinguishing between different connectivity patterns associated with varying clinical outcomes in multiple sclerosis (MS). Seventy-six people diagnosed with MS were scanned using a SIEMENS Prisma Fit 3T magnetic resonance imaging (MRI), employing both conventional (T1w and fluid-attenuated inversion recovery) and advanced diffusion MRI sequences from which fractional anisotropy (FA) and microscopic FA (µFA) maps were generated. Using automated fiber quantification (AFQ), we assessed diffusion profiles across multiple white matter (WM) pathways to measure the sensitivity of anisotropy diffusion metrics in detecting localized tissue damage. In parallel, we analyzed structural brain connectivity in a specific patient cohort to fully grasp its relationships with cognitive and physical clinical outcomes. This evaluation comprehensively considered different patient categories, including cognitively preserved (CP), mild cognitive deficits (MCD), and cognitively impaired (CI) for cognitive assessment, as well as groups distinguished by physical impact: those with mild disability (Expanded Disability Status Scale [EDSS] <=3) and those with moderate-severe disability (EDSS >3). In our initial objective, we employed Ridge regression to forecast the presence of focal MS lesions, comparing the performance of µFA and FA. µFA exhibited a stronger association with tissue damage and a higher predictive precision for focal MS lesions across the tracts, achieving an R-squared value of .57, significantly outperforming the R-squared value of .24 for FA (p-value <.001). In structural connectivity, µFA exhibited more pronounced differences than FA in response to alteration in both cognitive and physical clinical scores in terms of effect size and number of connections. Regarding cognitive groups, FA differences between CP and MCD groups were limited to 0.5% of connections, mainly around the thalamus, while µFA revealed changes in 2.5% of connections. In the CP and CI group comparison, which have noticeable cognitive differences, the disparity was 5.6% for FA values and 32.5% for µFA. Similarly, µFA outperformed FA in detecting WM changes between the MCD and CI groups, with 5% versus 0.3% of connections, respectively. When analyzing structural connectivity between physical disability groups, µFA still demonstrated superior performance over FA, disclosing a 2.1% difference in connectivity between regions closely associated with physical disability in MS. In contrast, FA spotted a few regions, comprising only 0.6% of total connections. In summary, µFA emerged as a more effective tool than FA in predicting MS lesions and identifying structural changes across patients with different degrees of cognitive and global disability, offering deeper insights into the complexities of MS-related impairments.

Diffusion tensor imaging metrics associated with future disability in multiple sclerosis.

The relationship between brain diffusion microstructural changes and disability in multiple sclerosis (MS) remains poorly understood. We aimed to explore the predictive value of microstructural properties in white (WM) and grey matter (GM), and identify areas associated with mid-term disability in MS patients. We studied 185 patients (71% female; 86% RRMS) with the Expanded Disability Status Scale (EDSS), timed 25-foot walk (T25FW), nine-hole peg test (9HPT), and Symbol Digit Modalities Test (SDMT) at two time-points. We used Lasso regression to analyse the predictive value of baseline WM fractional anisotropy and GM mean diffusivity, and to identify areas related to each outcome at 4.1 years follow-up. Motor performance was associated with WM (T25FW: RMSE = 0.524, R2 = 0.304; 9HPT dominant hand: RMSE = 0.662, R2 = 0.062; 9HPT non-dominant hand: RMSE = 0.649, R2 = 0.139), and SDMT with GM diffusion metrics (RMSE = 0.772, R2 = 0.186). Cingulum, longitudinal fasciculus, optic radiation, forceps minor and frontal aslant were the WM tracts most closely linked to motor dysfunction, and temporal and frontal cortex were relevant for cognition. Regional specificity related to clinical outcomes provide valuable information that can be used to develop more accurate predictive models that could improve therapeutic strategies.

[Thymectomy in thymomatous and non-thymomatous myasthenia gravis: analysis of a cohort of 46 patients]. / Timectomía en miastenia grave timomatosa y no timomatosa: análisis de una cohorte de 46 pacientes.

INTRODUCTION: Factors predicting remission after thymectomy for myasthenia gravis are not well known. AIM: To analyze the clinical evolution of the patients after this intervention and discuss about predictors of response. PATIENTS AND METHODS: We retrospectively reviewed all clinical data of thymectomies in myasthenia gravis patients performed at our hospital between 2006 from 2016. Using the MGFA-PIS classification, «complete stable remission¼, «pharmacologic remission¼, «minimal manifestations¼ and «improved¼ were defined as «good clinical outcome¼, and «unchanged¼, «worse¼, «exacerbation¼ or «died¼, as «poor clinical outcome¼. RESULTS: In 46 consecutive thymectomies for myasthenia gravis, women comprised 71.7%. Median age was 37 years and 10.9% had concomitant autoimmune disorders associated. Thymoma (23.96%) was more frequent in older patients (53 ± 20 vs 33 ± 24 years) and men (54.5% vs 18.8%). A year after thymectomy, 28.2% of patients were in poor clinical outcome group and 54.3% had good clinical outcome. On univariate analysis, thymomatous myasthenia was associated with poor clinical outcome a year after surgical intervention. After ten years of follow-up, 9.8% reached complete stable remission, a total of 32 patients (78%) had a favourable outcome and thymoma was not correlated. CONCLUSION: Thymectomy is considered an effective treatment for myasthenia gravis but the benefit is not immediate. The presence of thymoma may determine a worse initial clinical response following thymectomy in patients with myasthenia gravis.

TITLE: Timectomía en miastenia grave timomatosa y no timomatosa: análisis de una cohorte de 46 pacientes.Introducción. En la actualidad, los factores predictores de remisión de la enfermedad en la miastenia grave tras una timectomía no están claramente establecidos. Objetivo. Analizar la evolución clínica de los pacientes tras esta intervención y abordar los posibles determinantes pronósticos. Pacientes y métodos. Se analizaron retrospectivamente los registros de pacientes con miastenia grave timectomizados en nuestro centro entre 2006 y 2016. Se utilizó la escala Miasthenya Gravis Foundation of America-Post Intervention Status agrupando las categorías «remisión completa estable¼, «remisión farmacológica¼, «manifestaciones mínimas¼ y «mejoría¼ como «buen resultado clínico¼, y las categorías «sin cambios¼, «empeoramiento¼, «exacerbación¼ y «muerte¼, como «mal resultado clínico¼. Resultados. Se analizaron 46 timectomías de pacientes con miastenia grave, un 71,7% mujeres. La mediana de edad era de 37 años y el 10,9% asociaba enfermedades autoinmunes. El timoma (23,9%) fue más frecuentes en los varones (54,5% frente a 18,8%) y a mayor edad (53 ± 20 frente a 33 ± 24 años). Un año después de la timectomía, el 28,2% se encontraba en el grupo de mal resultado clínico, y un 54,3%, en el de buen resultado clínico. En el análisis univariante, el timoma se asoció a peor resultado clínico al año de la intervención. Tras diez años de seguimiento, 32 pacientes (78%) alcanzaron un buen resultado clínico, un 9,8% en remisión completa estable, y el timoma no se correlacionó como factor de mal pronóstico. Conclusión. La timectomía se considera un tratamiento efectivo, pero sin beneficio inmediato. La presencia de timoma podría determinar una respuesta clínica inicial peor tras la realización de una timectomía en pacientes con miastenia grave.

[Baroreflex activation therapy: One more step in the treatment of resistant arterial hypertension and chronic heart failure]. / La terapia de activación de barorreceptores, un paso más en el tratamiento de la hipertensión arterial resistente y la insuficiencia cardiaca.

The number of patients who suffer refractory arterial hypertension and chronic heart failure in advanced stages is currently increasing. The case is presented of a patient with an implantable cardioverter defibrillator, and with the dual indication of chronic heart failure and refractory arterial hypertension, who required the implanting of a baroreceptors activation therapy device of the carotid sinus. As far as it is known, it is the first case reported in Spain?

[Antibiotic diffusion to central nervous system]. / Difusión de los antibióticos en el sistema nervioso central.

Central nervous system (CNS) infections caused by pathogens with a reduced sensitivity to drugs are a therapeutic challenge. Transport of fluid and solutes is tightly controlled within CNS, where vasculature exhibits a blood-brain barrier (BBB).The entry of drugs, including antibiotics, into the cerebro-spinal fluid (CSF) is governed by molecular size, lipophilicity, plasma protein binding and their affinity to transport systems at the BBB. The ratio of the AUCCSF (Area under the curve in CSF)/AUCS (Area under the curve in serum) is the most accurate parameter to characterize drug penetration into the CSF. Linezolid, some fluoroquinolones and metronidazole get high CSF concentrations and are useful for treating susceptible pathogens. Some highly active antibiotic compounds with low BBB permeability can be directly administered into the ventricles together with concomitant intravenous therapy. The ideal antibiotic to treat CNS infections should be that with a small moderately lipophilic molecule, low plasma protein binding and low affinity to efflux pumps at BBB. Knowledge of the pharmacokinetics and pharmacodynamics of antibiotics at the BBB will assist to optimize antibiotic treatment in CNS infections. This article reviews the physicochemical properties of the main groups of antibiotics to assess which compounds are most promising for the treatment of CNS infections and how to use them in the daily clinical practice.

Silicosis en trabajadores expuestos aconglomerados de cuarzo / Silicosis in workers exposed to quartz conglomerates

Introducción: la silicosis, enfermedad crónica, causada por la inhalación de polvo de sílice cristalina, sigue siendo un problema de salud laboral vigente. El objetivo de la investigación consistió en estimar el riesgo de silicosis complicada y/o acelerada en trabajadores expuestos a polvo de sílice de conglomerados de cuarzo frente al riesgo de los trabajadores expuestos a roca ornamental. Método: se desarrolló un estudio analítico de casos y controles prevalentes en trabajadores cuya vigilancia de la salud se realizó en el instituto Nacional de Silicosis (España), entre el 1 de enero de 2008 y el 31 de diciembre de 2018 (N = 90). El valor de la significación de todos los contrastes de hipótesis realizados fue α = 0,05. Resultados: se determinó mayor riesgo de silicosis complicada en los trabajadores expuestos a polvo de sílice proveniente del uso de conglomerados de cuarzo mediante el cálculo de Chi cuadrado, con un total de 7 casos (46,67%) de silicosis complicada (p = 0,046). Conclusiones: existe mayor riesgo de silicosis complicada en los trabajadores expuestos a polvo de sílice proveniente del uso de conglomerados de cuarzo frente a los expuestos a polvo de sílice de roca ornamental. No se observó relación entre el riesgo de desarrollar silicosis acelerada y la exposición a conglomerados de cuarzo en la muestra analizada (AU)

Introduction: silicosis, a chronic disease caused by the inhalation of crystalline silica dust, continues to be a current occupational health problem. The objective of the research was to estimate the risk of complicated and/or accelerated silicosis in workers exposed to silica dust from quartz conglomerates compared to the risk of workers exposed to ornamental rock. Method: an analytical study of cases and controls prevalent in workers whose health surveillance was carried out at the National Institute of Silicosis (Spain), between January 1, 2008 and December 31, 2018 was developed (N = 90). The significance value of all the hypotheses tests performed was α = 0.05. Results: a higher risk of complicated silicosis was determined in workers exposed to silica dust from the use of quartz conglomerates by calculating Chi square, with a total of 7 cases (46.67%) of complicated silicosis (p = 0.046). Conclusions: there is a higher risk of complicated silicosis in workers exposed to silica dust from the use of quartz conglomerates compared to those exposed to silica dust from ornamental rock. No relationship was observed between the risk of developing accelerated silicosis and exposure to quartz conglomerates in the analyzed sample (AU)

Resultados de la ablación con catéter con mínimo o nulo empleo de fluoroscopia en pacientes pediátricos con taquiarritmias supraventriculares / Results of catheter ablation with zero or near zero fluoroscopy in pediatric patients with supraventricular tachyarrhythmias

Introducción y objetivos: La exposición a radiación ionizante en los procedimientos de ablación conlleva riesgos para la salud, sobre todo en pacientes pediátricos. Nuestro objetivo es comparar la seguridad y la eficacia de la ablación guiada por un sistema de navegación intracardiaca no fluoroscópica (SNINF) con las de la ablación guiada exclusivamente por fluoroscopia en pacientes pediátricos. Métodos: Se analizaron los resultados de la ablación con catéter en pacientes pediátricos con vías accesorias de riesgo o taquicardias supraventriculares remitidos a nuestro centro en un periodo de 6 años. Se compararon los procedimientos guiados solo por fluoroscopia (grupo A) y los guiados por SNINF (grupo B). Resultados: Se analizaron 120 procedimientos de ablación en 110 pacientes (edad, 11±3,2 años; el 70% varones), 62 procedimientos en el grupo A y 58 en el grupo B. No se encontraron diferencias significativas entre ambos grupos en éxito del procedimiento (el 95% del grupo A y el 93,5% del grupo B; p=0,53), complicaciones (el 1,7 frente al 1,6%; p=0,23) y recurrencia (el 7,3 frente al 6,9%; p=0,61). Sin embargo, el tiempo de fluoroscopia (mediana, 1,1 frente a 12 min; p<0,0005) y el tiempo de ablación (mediana, 96,5 frente a 133,5 s; p=0,03) fueron menores en el grupo B. La presencia de cardiopatía se comportó como un predictor independiente de recurrencia (p=0,03). Conclusiones: El SNINF para guiar los procedimientos de ablación en pacientes pediátricos reduce el tiempo de exposición a la radiación ionizante. Su empleo generalizado en las ablaciones pediátricas podría reducir el riesgo atribuido a la radiación (AU)

Introduction and objectives: Ionizing radiation exposure in catheter ablation procedures carries health risks, especially in pediatric patients. Our aim was to compare the safety and efficacy of catheter ablation guided by a nonfluoroscopic intracardiac navigation system (NFINS) with those of an exclusively fluoroscopy-guided approach in pediatric patients. Methods: We analyzed catheter ablation results in pediatric patients with high-risk accessory pathways or supraventricular tachycardia referred to our center during a 6-year period. We compared fluoroscopy-guided procedures (group A) with NFINS guided procedures (group B). Results: We analyzed 120 catheter ablation procedures in 110 pediatric patients (11±3.2 years, 70% male); there were 62 procedures in group A and 58 in group B. We found no significant differences between the 2 groups in procedure success (95% group A vs 93.5% group B; P=.53), complications (1.7% vs 1.6%; P=.23), or recurrences (7.3% vs 6.9%; P = .61). However, fluoroscopy time (median 1.1minutes vs 12minutes; P <.0005) and ablation time (median 96.5seconds vs 133.5seconds; P=.03) were lower in group B. The presence of structural heart disease was independently associated with recurrence (P=.03). Conclusions: The use of NFINS to guide catheter ablation procedures in pediatric patients reduces radiation exposure time. Its widespread use in pediatric ablations could decrease the risk of ionizing radiation (AU)

La terapia de activación de barorreceptores, un paso más en el tratamiento de la hipertensión arterial resistente y la insuficiencia cardiaca / Baroreflex activation therapy: One more step in the treatment of resistant arterial hypertension and chronic heart failure

En la actualidad son cada vez más los pacientes con hipertensión arterial refractaria (HTAR) que sufren insuficiencia cardiaca (IC) en fases avanzadas y que precisan dispositivos implantables para su tratamiento. Presentamos el caso de un paciente con un desfibrilador automático implantable (DAI) que precisó la colocación de un dispositivo de terapia de activación de barorreceptores (TAB) del seno carotídeo con la doble indicación de IC y HTAR. Hasta donde sabemos, se trata del primer caso realizado en nuestro país

The number of patients who suffer refractory arterial hypertension and chronic heart failure in advanced stages is currently increasing. The case is presented of a patient with an implantable cardioverter defibrillator, and with the dual indication of chronic heart failure and refractory arterial hypertension, who required the implanting of a baroreceptors activation therapy device of the carotid sinus. As far as it is known, it is the first case reported in Spain?

alpha-Amylase hypersensitivity in non-exposed millers.

Occupational hypersensitivity to alpha-amylase among bakers and workers in the pharmaceutical industry has been described. We present the results of skin tests and in vitro methods used to assess alpha-amylase sensitivity in 259 millers. There was no occupational contact with the enzyme in this population. Positive skin tests to this allergen were obtained in 16 subjects (6.18 per cent), specific IgE values were found in seven subjects (2.7 per cent), specific IgG was detected on 45 workers (17.37 per cent) and high values for IgG (> 2.5 absorbance units) were found in 12 subjects (4.63 per cent). Furthermore, specific IgE and IgG could be determined in several sera by immunoblotting. All these facts suggested that millers were sensitized to Aspergillus oryzae alpha-amylase, although the allergen was not used by these workers. A cross-reaction cannot be excluded; however, it is the authors' opinion that wheat or wheat flour is a natural substrate for fungi and that the moulds that grow on cereals or cereal-derived by-products need to secrete amylases to support their own development. Hence the workers may be indirectly sensitized to amylases.

Brote epidémico tóxico ocurrido en población trabajadora de una industria textil de Redondela (Pontevedra) / No disponible

No disponible

La investigación en seguridad y salud en el trabajo: ¿Un paso adelante? / Occupational health and safety research: are we moving forward?

No disponible

Exposición a carcinógenos laborales en España: aplicación de la base de datos CAREX / Occupational exposure to carcinogens in spain: application of the carex date base

CAREX es un sistema de información internacional sobre exposiciones laborales a carcinógenos conocidos y sospechosos en los 15 países de la Unión Europea. La base de datos de CAREX (CARcinogen EXposure) proporciona datos de exposición seleccionados y estimaciones del número de trabajadores expuestos por país, carcinógeno e industria. CAREX incluye datos de 139 agentes evalua­ dos por la lnternational Agency for Research on Cancer para cada uno de los 55 sectores de actividad económica de acuerdo a la clasificación de las Naciones Unidas. Las exposiciones laborales a estos carcinógenos fueron estimadas para el período 1990­1993. Alrededor de 32 millones de trabajadores (23% de los empleados) en los 15 países de la UE y 3,1 millones de trabajadores en España estaban expuestos a algunos de los agentes cancerígenos. En España, entre las exposiciones más frecuentes, se identificaron la radia­ción solar (1.084.000 trabajadores expuestos al menos el 75% de la jornada laboral), el humo de tabaco ambiental (670.000 trabaja­ dores expuestos el 75% del tiempo), el sílice cristalino (405.000 expuestos), el polvo de madera (398.000), el radón y sus productos de desintegración (280.000), el humo de escape de motor Diesel (274.000), el benceno (90.000), los metales pesados, tales como el cromo (57.000), el cadmio (16.000) o el níquel (43.000), el amianto (57.000) y formaldehído (71.000). El número de trabajadores expuestos a carcinógenos conocidos o sospechosos generados por CAREX constituye las primeras estimaciones publicadas para la UE y para España. Aunque estas estimaicones deberían ser consideradas como preliminares, indica claramente que a principios de los años noventa existía un elevado número de trabajadores expuestos a cancerígenos en su lugar de trabajo (AU)

CAREX is an international information system for the estimation of the numbers of workers exposed to established and suspected human carcinogens in the member states of the European Union (EU). The CAREX database was designed to provide selected ex­ posure data and documented estimates of the number of workers exposed to carcinogens by country, carcinogen, and industry. CA­ REX includes data on 139 agents evaluated by the lnternational Agency for Research on Cancer, displayed across the 55 industrial classes. Occupational exposures were estimated for 1990­199 3. About 32 million workers (23% of those employed) in the EU and 3.1 million workers in Spain were exposed to any carcinogen agents. The more common exposures in Spain were solar radiation (1,084,000 workers exposed at least 75% of working time), environmental tobacco smoke ( 670,000 workers exposed at least 7 5% of working time), crystalline silica ( 405 ,000 exposed), wood dust (398,000), Diesel exhaust benzene (90,000), chromium VI compounds (57,000), cadmium (16,000), nickel (43,000), asbestos (57,000), and formaldehyde (71,000). The number of workers exposed to established and suspected human carcinogens generated by the CAREX has been the first published estimates for EU and Spain. These preliminary estimates indicare that in the early 1990s, a substancial proportion of workers in the EU were exposed to carcinogen (AU)