High frequency oscillations in human memory and cognition: a neurophysiological substrate of engrams?

Despite advances in understanding the cellular and molecular processes underlying memory and cognition, and recent successful modulation of cognitive performance in brain disorders, the neurophysiological mechanisms remain underexplored. High frequency oscillations beyond the classic electroencephalogram spectrum have emerged as a potential neural correlate of fundamental cognitive processes. High frequency oscillations are detected in the human mesial temporal lobe and neocortical intracranial recordings spanning gamma/epsilon (60-150 Hz), ripple (80-250 Hz) and higher frequency ranges. Separate from other non-oscillatory activities, these brief electrophysiological oscillations of distinct duration, frequency and amplitude are thought to be generated by coordinated spiking of neuronal ensembles within volumes as small as a single cortical column. Although the exact origins, mechanisms, and physiological roles in health and disease remain elusive, they have been associated with human memory consolidation and cognitive processing. Recent studies suggest their involvement in encoding and recall of episodic memory with a possible role in the formation and reactivation of memory traces. High frequency oscillations are detected during encoding, throughout maintenance, and right before recall of remembered items, meeting a basic definition for an engram activity. The temporal coordination of high frequency oscillations reactivated across cortical and subcortical neural networks is ideally suited for integrating multimodal memory representations, which can be replayed and consolidated during states of wakefulness and sleep. High frequency oscillations have been shown to reflect coordinated bursts of neuronal assembly firing and offer a promising substrate for tracking and modulation of the hypothetical electrophysiological engram.

Categorization of the amyotrophic lateral sclerosis population via the clinical determinant of post-onset ΔFS for study design and medical practice.

The amyotrophic lateral sclerosis (ALS) functional rating scale-revised (ALSFRS-R) has become the most widely utilized measure of disease severity in patients with ALS, with change in ALSFRS-R from baseline being a trusted primary outcome measure in ALS clinical trials. This is despite the scale having several established limitations, and although alternative scales have been proposed, it is unlikely that these will displace ALSFRS-R in the foreseeable future. Here, we discuss the merits of delta FS (ΔFS), the slope or rate of ALSFRS-R decline over time, as a relevant tool for innovative ALS study design, with an as yet untapped potential for optimization of drug effectiveness and patient management. In our view, categorization of the ALS population via the clinical determinant of post-onset ΔFS is an important study design consideration. It serves not only as a critical stratification factor and basis for patient enrichment but also as a tool to explore differences in treatment response across the overall population; thereby, facilitating identification of responder subgroups. Moreover, because post-onset ΔFS is derived from information routinely collected as part of standard patient care and monitoring, it provides a suitable patient selection tool for treating physicians. Overall, post-onset ΔFS is a very attractive enrichment tool that is, can and should be regularly incorporated into ALS trial design.

European Academy of Neurology (EAN) guideline on the management of amyotrophic lateral sclerosis in collaboration with European Reference Network for Neuromuscular Diseases (ERN EURO-NMD).

BACKGROUND: This update of the guideline on the management of amyotrophic lateral sclerosis (ALS) was commissioned by the European Academy of Neurology (EAN) and prepared in collaboration with the European Reference Network for Neuromuscular Diseases (ERN EURO-NMD) and the support of the European Network for the Cure ALS (ENCALS) and the European Organization for Professionals and Patients with ALS (EUpALS). METHODS: Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was used to assess the effectiveness of interventions for ALS. Two systematic reviewers from Cochrane Response supported the guideline panel. The working group identified a total of 26 research questions, performed systematic reviews, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available. RESULTS: A guideline mapping effort revealed only one other ALS guideline that used GRADE methodology (a National Institute for Health and Care Excellence [NICE] guideline). The available evidence was scarce for many research questions. Of the 26 research questions evaluated, the NICE recommendations could be adapted for 8 questions. Other recommendations required updates of existing systematic reviews or de novo reviews. Recommendations were made on currently available disease-modifying treatments, multidisciplinary care, nutritional and respiratory support, communication aids, psychological support, treatments for common ALS symptoms (e.g., muscle cramps, spasticity, pseudobulbar affect, thick mucus, sialorrhea, pain), and end-of-life management. CONCLUSIONS: This update of the guideline using GRADE methodology provides a framework for the management of ALS. The treatment landscape is changing rapidly, and further updates will be prepared when additional evidence becomes available.

Increased Incidence of TdT-negative Pre-B Acute Lymphoblastic Leukemia Associated With Poor Prognostic Features Among Mexican Children in Central Mexico.

Mexican and Hispanic children in Mexico and the United States, respectively, have the highest incidence and worst outcomes of pre-B acute lymphoblastic leukemia (ALL) compared with other racial/ethnic groups. Terminal deoxynucleotidyl transferase (TdT) is an intranuclear DNA polymerase normally present on immature lymphocytes (TdT-positive) and distinguishes ALL from mature lymphoid malignancies. We performed a multisite retrospective study to determine the incidence of TdT-negative precursor B-cell acute lymphoblastic leukemia (pre-B ALL) among Mexican, Caucasian, and US-born Hispanic children to correlate TdT expression with patient characteristics and known prognostic factors. Fisher exact test was performed for categorical variables and the Wilcoxon rank-sum test was used for continuous variables. TdT-negative pre-B ALL was most frequently identified in patients with National Cancer Institute high-risk disease ( P =0.014). TdT-negative expression was also most frequently associated with hypodiploid pre-B ALL ( P =0.001) and KMT2A gene rearrangement ( P =0.0012). Mexican children had the highest incidence of TdT-negative ALL compared with Caucasians and US Hispanics ( P <0.001), with an increased incidence of poor prognostic features as well. This study demonstrates significant differences in TdT-negative expression, genomic alterations, and leukemic ploidy based on race and ethnicity.

Clinical-epidemiological characterization of patients with long COVID in Mexico.

BACKGROUND: Long COVID is defined as the persistence of COVID-19 symptoms four weeks after having undergone acute infection, according to the most recent CDC definition. It is estimated that there are 65 million people affected by this entity, although other figures speak of 200 million. OBJECTIVE: To characterize the population affected by long COVID in Mexico. MATERIAL AND METHODS: Patients older than 18 years who agreed to answer an online survey and who met the criteria for long COVID were included. RESULTS: Data from 203 subjects were included, with 138 (68.0%) being found to be females, and average age to be 41.8 years; 29.6% had severe disease, and 70.4%, mild to moderate disease; 89.7% had received prior COVID-19 vaccination: 6.9% had received one dose; 31.5%, two doses; and 51.2%, three or more doses. The main risk factors were diabetes, overweight or obesity, and hypertension. The most commonly reported symptom was fatigue, followed by other neuropsychiatric manifestations. CONCLUSION: It is important for the population affected by long COVID to be characterized in order to generate diagnostic and treatment protocols.

ANTECEDENTES: El COVID persistente se define como la persistencia de síntomas de COVID-19 después de cuatro semanas de cursar con un cuadro agudo, según la definición más reciente de los Centers for Disease Control and Prevention. Se estima que existen 65 millones de personas afectadas por esta entidad, aunque algunos reportes indican 200 millones. OBJETIVO: Caracterizar a la población afectada por COVID persistente en México. MATERIAL Y MÉTODOS: Se incluyeron pacientes mayores de 18 años que consintieron responder a una encuesta en línea y que cumplían los criterios de COVID persistente. RESULTADOS: Se incluyeron los datos de 203 sujetos. Se identificó que 138 (68.0 %) contestaron ser del sexo femenino, con una media de edad de 41.8 años; 29.6 % presentó enfermedad grave y 70.4 %, enfermedad leve a moderada; 89.7 % había recibido vacunas previas para COVID-19: 6.9 %, una dosis; 31.5 %, dos dosis; y 51.2 %, tres o más dosis. Los principales factores de riesgo fueron diabetes, sobrepeso u obesidad e hipertensión arterial sistémica. El principal síntoma reportado fue fatiga, seguido de otras manifestaciones neuropsiquiátricas. CONCLUSIÓN: Es importante caracterizar a la población para generar protocolos de diagnóstico y tratamiento.

Race Dynamics in Triathlon Mixed-Team-Relay Meaningfully Changes with The New Regulation Towards Paris 2024.

Mixed-Team-Relay (MTR) triathlon is a novel Olympic discipline whose performance determinants and tactical behaviors have barely been studied. Additionally, a regulatory change has been made to the male and female relay order for the Paris 2024 Olympics. Therefore, this study aimed to determine the performance determinants and race dynamics as a function of competitive level on the new regulated MTR triathlon. Results from 129 national teams, (516 elite triathletes) across five MTR World Triathlon Series and two MTR European Championships in 2022 and 2023, were analyzed. Split times, average speeds, time behind the race leader (gap), partial and finishing positions, pack position as well as the rank positions of every segment, relay leg, and overall race were computed. Decision tree analyses were conducted as a predictive method for the overall results, and correspondence analyses were conducted to examine the relationship between the different relay legs and segments and the finishing positions. The performance of the fourth leg was the most relevant for overall result (30%), as well as the fourth running leg (16%) and the female legs performance (7%). Medallist relay teams were characterized by displaying a differential speed lower than 0.5 and 0.83 km/h, respectively, from the best-ranking athletes in the Legs 1 and 4. Furthermore, staying in the front pack after the second swimming leg showed a great relationship with achieving a medal position. New MTR triathlon rules shift race dynamics, emphasizing individual efforts in cycling and swimming, while maintaining the crucial importance of running.

Classification performance assessment for imbalanced multiclass data.

The evaluation of diagnostic systems is pivotal for ensuring the deployment of high-quality solutions, especially given the pronounced context-sensitivity of certain systems, particularly in fields such as biomedicine. Of notable importance are predictive models where the target variable can encompass multiple values (multiclass), especially when these classes exhibit substantial frequency disparities (imbalance). In this study, we introduce the Imbalanced Multiclass Classification Performance (IMCP) curve, specifically designed for multiclass datasets (unlike the ROC curve), and characterized by its resilience to class distribution variations (in contrast to accuracy or F ß -score). Moreover, the IMCP curve facilitates individual performance assessment for each class within the diagnostic system, shedding light on the confidence associated with each prediction-an aspect of particular significance in medical diagnosis. Empirical experiments conducted with real-world data in a multiclass context (involving 35 types of tumors) featuring a high level of imbalance demonstrate that both the IMCP curve and the area under the IMCP curve serve as excellent indicators of classification quality.

Helminth fauna of the black goby Gobius niger L. (Gobiiformes: Gobiidae) from the Finnish Archipelago, Baltic Sea: Molecular and morphological data.

Black gobies (Gobius niger) from the Finnish Archipelago, Baltic Sea, were screened for helminth infections in summer 2020. Helminths were identified morphologically and/or molecularly. Altogether 26 novel sequences were generated and analysed using maximum likelihood estimation. Morphological and phylogenetic analyses based on mitochondrial genes revealed the presence of 8 species belonging to the Digenea (Diplostomum mergi Lineage 3), Cestoda (Bothriocephalus scorpii), Nematoda (Contracaecum rudolphii A, Cucullanus sp. and Hysterothylacium aduncum), and Acanthocephala (a putative new species of Corynosoma, Corynosoma semerme and Neoechinorhynchus sp.). Phylogenetic and comparative sequence analyses revealed that the putative new acanthocephalan species is closely related to C. neostrumosum described from the Caspian seal, Pusa caspica, in the Caspian Sea. The black goby represents a new host record for four parasite species (Diplostomum mergi Lineage 3, Contracaecum rudolphii A, Corynosoma semerme and Corynosoma sp.). The Finnish Archipelago is a novel locality record for three species (Corynosoma sp., Diplostomum mergi Lineage 3 and Bothriocephalus scorpii).

Advance Monitoring of COVID-19 Incidence Based on Taxi Mobility: The Infection Ratio Measure.

The COVID-19 pandemic has had a profound impact on various aspects of our lives, affecting personal, occupational, economic, and social spheres. Much has been learned since the early 2020s, which will be very useful when the next pandemic emerges. In general, mobility and virus spread are strongly related. However, most studies analyze the impact of COVID-19 on mobility, but not much research has focused on analyzing the impact of mobility on virus transmission, especially from the point of view of monitoring virus incidence, which is extremely important for making sound decisions to control any epidemiological threat to public health. As a result of a thorough analysis of COVID-19 and mobility data, this work introduces a novel measure, the Infection Ratio (IR), which is not sensitive to underestimation of positive cases and is very effective in monitoring the pandemic's upward or downward evolution when it appears to be more stable, thus anticipating possible risk situations. For a bounded spatial context, we can infer that there is a significant threshold in the restriction of mobility that determines a change of trend in the number of infections that, if maintained for a minimum period, would notably increase the chances of keeping the spread of disease under control. Results show that IR is a reliable indicator of the intensity of infection, and an effective measure for early monitoring and decision making in smart cities.

Surface plasmon resonance microscopy identifies glycan heterogeneity in pancreatic cancer cells that influences mucin-4 binding interactions.

Membrane proteins are the main targets of therapeutic drugs and most of them are glycosylated. Glycans play pivotal roles in several biological processes, and glycosylation changes are a well-established hallmark of several types of cancer, including pancreatic cancer, that contribute to tumor growth. Mucin-4 (MUC-4) is a membrane glycoprotein which is associated with pancreatic cancer and metastasis, and it has been targeted as a promising vaccine candidate. In this study, Surface Plasmon Resonance Microscopy (SPRM) was implemented to study complex influences of the native N-glycan cellular environment on binding interactions to the MUC-4 receptor as this is currently the only commercially available label-free technique with high enough sensitivity and resolution to measure binding kinetics and heterogeneity on single cells. Such unique capability enables for a more accurate understanding of the "true" binding interactions on human cancer cells without disrupting the native environment of the target MUC-4 receptor. Removal of N-linked glycans in pancreatic cancer cells using PNGase F exposed heterogeneity in Concanavalin (Con A) binding by revealing three new binding populations with higher affinities than the glycosylated control cells. Anti-MUC-4 binding interactions of enzymatically N-linked deglycosylated pancreatic cancer cells produced a 25x faster association and 37x higher affinity relative to the glycosylated control cells. Lastly, four interaction modes were observed for Helix Pomatia Agglutinin (HPA) binding to the glycosylated control cells, but shifted and increased in activity upon removal of N-linked glycans. These results identified predominant interaction modes of glycan and MUC-4 in pancreatic cancer cells, the kinetics of their binding interactions were quantified, and the influence of N-linked glycans in MUC-4 binding interactions was revealed.

Elucidating Structural Stability, Bandgap, and Photocatalytic Hydrogen Evolution of (H2O/DMF)@HKUST-1 Host-Guest Systems.

The H2O@HKUST-1 and DMF@HKUST-1 systems were experimental and computationally assessed, employing XRD/TGA/FT-IR/DFT-calculations, evidencing that H2O or DMF coordinated to Cu, modulating HKUST-1 photocatalytic properties. DMF@HKUST-1 has narrower bandgap promoting higher-crystallinity and light-harvesting. H2O@HKUST-1 showed smaller particle sizing and sharp morphology. Theoretical models, (H2O)1@HKUST-1 and (DMF)1@HKUST-1, containing one coordinated molecule, elucidated bandgap modulation associated with infiltration. H2O@HKUST-1/DMF@HKUST-1 presented bandgaps [eV] of 3.6/3.4, by Tauc plots, and 3.55/3.26, by theoretical calculations, narrowing bandgap, compared with non-solvated HKUST-1(HKUST-1NS). Both composites raised the valence band (VB) and lowered the conduction band (CB), but DMF@HKUST-1 most raised VB. Topological analysis revealed that guests i) with higher electronic density, raised VB, and ii) induced π-backbonding, lowering CB. DMF@HKUST-1 presented a higher photocatalytic hydrogen evolution (µmol), 26.45, in the first 30 min of the reaction, nevertheless, H2O@HKUST-1 presented a competitive activity, of 17.32. In large periods, H2O@HKUST-1/DMF@HKUST-1 showed practically the same hydrogen evolution, 45.50/49.03.

Mutations in the tail and rod domains of the neurofilament heavy-chain gene increase the risk of ALS.

OBJECTIVE: Neurofilament heavy-chain gene (NEFH) variants are associated with multiple neurodegenerative diseases, however, their relationship with ALS has not been robustly explored. Still, NEFH is commonly included in genetic screening panels worldwide. We therefore aimed to determine if NEFH variants modify ALS risk. METHODS: Genetic data of 11,130 people with ALS and 7,416 controls from the literature and Project MinE were analysed. We performed meta-analyses of published case-control studies reporting NEFH variants, and variant analysis of NEFH in Project MinE whole-genome sequencing data. RESULTS: Fixed-effects meta-analysis found that rare (MAF <1%) missense variants in the tail domain of NEFH increase ALS risk (OR 4.55, 95% CI 2.13-9.71, p < 0.0001). In Project MinE, ultrarare NEFH variants increased ALS risk (OR 1.37 95% CI 1.14-1.63, p = 0.0007), with rod domain variants (mostly intronic) appearing to drive the association (OR 1.45 95% CI 1.18-1.77, pMadsen-Browning = 0.0007, pSKAT-O = 0.003). While in the tail domain, ultrarare (MAF <0.1%) pathogenic missense variants were also associated with higher risk of ALS (OR 1.94, 95% CI 0.86-4.37, pMadsen-Browning = 0.039), supporting the meta-analysis results. Finally, several tail in-frame deletions were also found to affect disease risk, however, both protective and pathogenic deletions were found in this domain, highlighting an intricate architecture that requires further investigation. INTERPRETATION: We showed that NEFH tail missense and in-frame deletion variants, and intronic rod variants are risk factors for ALS. However, they are not variants of large effect, and their functional impact needs to be clarified in further studies. Therefore, their inclusion in routine genetic screening panels should be reconsidered.

Prevalencia de subtipos de cáncer de mama y su asociación con factores reproductivos / Prevalence of breast cancer subtypes and their association with reproductive factors

Introducción: Los factores reproductivos se asocian con cáncer de mama. Actualmente se estudia el comportamiento según subtipos moleculares. Objetivo: Establecer la prevalencia de estos subtipos y su asociación con factores reproductivos en mujeres atendidas en centros del nororiente colombiano. Método: Estudio observacional de corte transversal, en mujeres con cáncer de mama subtipos luminales y HER2 durante 2012-2021. Se indagaron variables sociodemográficas, factores reproductivos y estadio tumoral. Resultados: En total, 347 pacientes cumplieron criterios de elegibilidad, correspondiendo a luminal A el 49,8% (intervalo de confianza del 95% [IC95%]: 44,5-55,1), a luminal B el 29,1% (IC95%: 24,3-33,9) y a HER2 el 15,5% (IC95%: 11,7-19,4). Las mujeres con tumores de mama luminal B tenían más riesgo de tener estadios localmente avanzados (odds ratio [OR]: 1,83; IC95%: 1,11-3,01; p = 0,02). Agrupando los subtipos luminales frente a HER2 se encontró que el 40,72% de las pacientes con subtipos luminales no habían lactado, frente al 69,71% con HER2 (diferencia estadísticamente significativa a favor de luminal A; OR: 1,91; IC95%: 1,02-3,53; p = 0,041). Conclusiones: La prevalencia de tumores luminales es del 84,5%. Existe asociación diferencial entre el antecedente de lactancia materna y la aparición de subtipos luminales, es decir, las mujeres que no lactaron se corresponden con mayor frecuencia con HER2. No se estableció asociación con otros factores estudiados.

Introduction: Stimulus-estrogenic factors are associated with breast cancer. Currently, the behavior according to molecular subtypes is being studied. Objective: To establish the prevalence of these subtypes and their association with reproductive factors in women attended in centers in northeastern Colombia. Method: Observational cross-sectional study in women with breast cancer subtypes luminal and HER2 during 2012 -2021. Sociodemographic variables, stimulus-estrogenic factors and tumor stage were investigated. Results: In total, 347 patients met eligibility criteria, corresponding to luminal A 49.8% (95% confidence interval [95%CI]: 44.5-55.1), luminal B 29.1% (95%CI: 24.3-33.9) and HER2 15.5% (95%CI: 11.7-19.4). Women with luminal B breast tumors were at higher risk of having locally advanced stages (odds ratio [OR]: 1.83; 95%CI: 1.11-3.01; p = 0.02). Grouping the luminal subtypes versus HER2 showed that 40.72% of patients with luminal subtypes had not lactated, compared to 69.71% HER2 (statistically significant difference in favor of luminal A; OR: 1.91; 95%CI: 1.02-3.53; p = 0.041). Conclusions: The prevalence of luminal tumors is 84.5%. There is a differential association between the history of breastfeeding and the appearance of luminal subtypes, i.e., women who did not breastfeed are more likely to have HER2. No association was established with other factors studied.

Ultrasonido Point-Of-Care (POCUS) durante la reanimación cardiopulmonar para el diagnóstico de causas reversibles de arresto cardiaco / Point-Of-Care ultrasound (POCUS) during cardiopulmonary resuscitation for the diagnosis of reversible causes of cardiac arrest / Ultrassonografia Point-of-Care (POCUS) durante a reanimação cardiopulmonar para o diagnóstico de causas reversíveis de parada cardíaca

Resumen: La ultrasonografía enfocada al paciente crítico o «ultrasonido Point-Of-Care¼ (POCUS) es una herramienta utilizada en la cabecera del paciente en distintas áreas de la medicina crítica y servicios de emergencias debido a su practicidad y a que provee gran información de forma rápida y no invasiva para realizar diagnósticos y abordajes terapéuticos. El arresto cardiaco (AC) es una situación crítica que requiere una adecuada reanimación cardiopulmonar (RCP) y en la que es crucial la identificación de la etiología para realizar una intervención rápida y lograr la resolución de la misma, particularmente en el escenario de una actividad eléctrica sin pulso (AESP) en la que la ecografía cobra vital importancia. La implementación de protocolos de reanimación cardiopulmonar apoyados de un abordaje ultrasonográfico es factible y de gran utilidad para la identificación etiológica del AC y la resolución de causas específicas.

Abstract: Ultrasound focused on the critical patient or «Point-Of-Care ultrasound¼ (POCUS) is a tool used at the patient's bedside in different areas of critical medicine and emergency services due to its practicality as it provides great information quickly and non-invasive for diagnostic and therapeutic approaches. Cardiac arrest (CA) is a critical situation that requires adequate cardiopulmonary resuscitation (CPR), and in which the identification of the etiology is crucial to carry out a rapid intervention and achieve its resolution, particularly in the setting of a pulseless electrical activity (AESP) in which ultrasound is of vital importance. The implementation of cardiopulmonary resuscitation protocols supported by an ultrasound approach is feasible and of great utility for the etiological identification of CA and the resolution of specific causes.

Resumo: A ultrassonografia focada em pacientes críticos ou «Point-Of-Care ultra-som¼ (POCUS) é uma ferramenta utilizada à beira do leito do paciente em diferentes áreas da medicina crítica e serviços de emergência devido à sua praticidade e ao fato de fornecer uma grande quantidade de informações rapidamente e não invasivo para abordagens diagnósticas e terapêuticas. A parada cardíaca (PC) é uma situação crítica que requer uma adequada ressuscitação cardiopulmonar (RCP) e na qual a identificação da etiologia é crucial para a rápida intervenção e resolução, particularmente no cenário de uma atividade elétrica sem pulso (AESP) em qual o ultra-som é de vital importância. A implementação de protocolos de ressuscitação cardiopulmonar apoiados por uma abordagem ultrassonográfica é viável e muito útil para a identificação etiológica do RAC e resolução de causas específicas.

Aplicaciones e implicaciones de la pausa al final de la inspiración en ventilación mecánica / Applications and implications of end-inspiratory pause in mechanical ventilation / Aplicações e implicações da pausa ao final da inspiração na ventilação mecânica

Resumen: El uso de la pausa al final de la inspiración (PFI) en ventilación mecánica data de hace más de 50 años y con mayor impulso en la década de los 70, se le atribuye una mejoría en la presión parcial de oxígeno arterial (PaO2) al incrementar la presión media de la vía aérea (Pma), mayor aclaramiento de la presión parcial de dióxido de carbono arterial (PaCO2) y permite la monitorización de la presión meseta (Pmeseta) en la mecánica ventilatoria; sin embargo, los estudios clínicos sobre su uso son escasos y controversiales. En este artículo se abordan los mecanismos fisiológicos, fisiopatológicos y la evidencia sobre el uso de la PFI en ventilación mecánica (VM).

Abstract: The use of the end inspiratory pause (EIP) in mechanical ventilation has been going on for more than 50 years and with greater momentum in the 1970s, an improvement in the partial pressure of arterial oxygen (PaO2) is attributed to the increase mean airway pressure, greater clearance of partial pressure of arterial carbon dioxide and allows monitoring of plateau pressure in ventilatory mechanics; However, the Clinical studies on its use are few and controversial. This article addresses the physiological and pathophysiological mechanisms and the evidence on the use of EIP in mechanical ventilation.

Resumo: A utilização da pausa ao final da inspiração (PFI) na ventilação mecânica remonta a mais de 50 anos e com maior impulso na década de 70, atribui-se uma melhora na pressão parcial de oxigênio arterial (PaO2) pelo aumento da pressão média das vias aéreas (Pma), uma maior depuração da pressão parcial de dióxido de carbono arterial (PaCO2) e permite a monitorização da pressão de platô (Pplateau) na mecânica ventilatória, porém estudos Os dados clínicos sobre seu uso são escassos e controversos. Este artigo aborda os mecanismos fisiológicos e fisiopatológicos e as evidências sobre o uso do PFI na ventilação mecânica (VM).

Aproximación hacia la evaluación de la aptitud clínica en residentes de cardiología. Diseño multicéntrico / Approach to cardiology residents clinical aptitude evaluation. Multicenter design

Resumen Introducción: Hasta donde se tiene conocimiento, la investigación que se presenta constituye el primer trabajo multicéntrico en México que estudia el desarrollo de la aptitud clínica en unidades formadoras de cardiólogos. Objetivo: Determinar el grado de desarrollo de la aptitud clínica en residentes de cardiología en tres unidades médicas de alta especialidad. Métodos: Diseño transversal multicéntrico. Se analizaron todos los estudiantes del ciclo académico 2019-2020. Se construyó un instrumento que evaluó la aptitud clínica a partir de ocho indicadores y 170 ítems; la validez conceptual/de contenido y la confiabilidad fueron valoradas por cinco cardiólogos con experiencia docente y en investigación educativa. Resultados: Por indicador y año de residencia se observaron diferencias estadísticas significativas en la sede CMN20Nov; en HCSXXI e INCICh se observaron diferencias estadísticamente significativas en uno de ocho indicadores. Se estimaron diferencias entre residentes R1 (n = 41) de las tres sedes por indicador, con significación estadística en tres de ocho indicadores. El resultado fue semejante al comparar R2 (n = 35) y R3 (n = 43). Conclusiones: El grado de desarrollo de la aptitud clínica se puede considerar medio en las tres sedes académicas, probablemente debido a que el instrumento exploró situaciones clínicas problematizadas que exigieron del residente la reflexión crítica de su experiencia clínica.

Abstract Introduction: To the best of our knowledge, the research herein presented is the first multicenter study in Mexico to analyze the development of clinical aptitude in medical units that train cardiologists. Objective: To determine the degree of development of clinical aptitude in cardiology residents at three High Specialty Medical Units. Methods: Multicenter, cross-sectional design. All students of the 2019-2020 academic year were included in the study. An instrument was constructed that evaluated clinical aptitude based on eight indicators and 170 items; conceptual/content validity and reliability were assessed by five cardiologists with teaching and educational research experience. Results: By indicator and year of residence, significant statistical differences were observed in the CMN20Nov academic site. At HCSXXI and INCICh, statistically significant differences were observed in one of eight indicators. Differences between R1 residents (n = 41) of all three academic sites were estimated by indicator, with statistical significance being recorded in three of eight indicators. Between R2 (n = 35) and between R3 residents (n = 43), the result was similar. Conclusions: The degree of clinical aptitude development can be considered intermediate in all three academic sites, probably because the instrument explored problematized clinical situations that required the residents to critically reflect on their clinical experience.

Análisis de la calidad de la anticoagulación con antagonistas de la vitamina K en tres escenarios clínicos en México / Analysis of the quality of anticoagulation with vitamin K antagonists in three clinical scenarios in Mexico

Resumen Introducción: Los antagonista de la vitamina K (AVK) son una alternativa terapéutica en los pacientes con enfermedad tromboembólica venosa; sin embargo, numerosos factores afectan su farmacología. Objetivo: Evaluar la calidad de la anticoagulación AVK durante tres diferentes periodos en México. Métodos: Estudio prospectivo, anidado en cohortes de pacientes en tres escenarios clínicos entre los años 2013-2019. Se incluyeron pacientes no hospitalizados con indicación para recibir AVK por al menos 12 meses, quienes fueron manejados de acuerdo con el criterio del médico tratante. Resultados: Las características generales de los pacientes fueron similares entre los grupos, excepto por la indicación para usar los AVK. Se analizaron los resultados de 4148 pacientes y 38 548 evaluaciones de INR. Los tiempos en rango terapéutico durante las tres fases del estudio y los datos acumulados fueron significativamente mayores en la clínica de anticoagulación. Solo el número de visitas de control de los pacientes se asoció significativamente con los resultados, a diferencia de la edad, el sexo y el tipo de AVK. Conclusiones: Los AVK se utilizan ampliamente, pero es difícil alcanzar la meta terapéutica, sobre todo en servicios clínicos no especializados. La creación de clínicas de anticoagulación es una necesidad urgente en el sistema mexicano de salud.

Abstract Introduction: Vitamin K antagonists (VKA) are a therapeutic alternative in patients with venous thromboembolic disease; however, numerous factors affect their pharmacology. Objective: To evaluate the quality of VKA anticoagulation at three different time periods in Mexico. Methods: Prospective study, nested in patient cohorts at three different clinical scenarios between 2013 and 2019. Outpatients with indication for treatment with VKAs for at least 12 months were included. Patients were managed according to the criteria of the treating physician. Results: Patient general characteristics were similar between groups, except for the VKA indication. The results of 4,148 patients and 38,548 INR assessments were analyzed. The times in therapeutic range during the three phases of the study and pooled data were significantly higher for the anticoagulation clinic. Only the number of patient visits was significantly associated with the results, unlike age, gender, and type of VKA. Conclusions: VKAs are widely used, but it is difficult for therapeutic goals to be achieved, especially in non-specialized clinical services. Creation of anticoagulation clinics is an urgent need for the Mexican health system.

Fistulización a recto de un teratoma quístico maduro, una rara complicación / Rectal fistulization of a mature cystic teratoma, a rare complication

RESUMEN Los teratomas quísticos maduros son los tumores ováricos más frecuentes. La fistulización de estos a órganos vecinos (colon, intestino delgado y vejiga) es una complicación que cuando se presenta nos obliga a descartar un proceso infiltrativo. Tanto la malignización como la formación de fistulas son complicaciones excepcionales. Está descrito en la bibliografía la malignización como mecanismo de formación de dichas fistulas. Este hecho nos suele obligar a llevar a cabo intervenciones agresivas, como exenteraciones pélvicas anteriores y posteriores. Sin embargo, una revisión de los casos publicados (18) muestra que sólo el 22 % de las fistulas son resultado de una malignización de dicho teratoma. Presentamos una paciente con un teratoma quístico maduro que fistulizó a recto y su manejo en nuestro servicio. Precis: La fistulización a órganos vecinos de un teratoma es una complicación excepcional que requiere un diagnóstico preciso puesto que no siempre es secundaria a neoplasia.

ABSTRACT Mature cystic teratomas are the most common ovarian tumors. The fistulization of these teratomas to adjacent organs (colon, small intestine and bladder) is a complication that when it occurs forces us to rule out an infiltrative process. Together with malignancy, the fistula is a rare complication. Literature describes malignancy as a mechanism for the formation of these fistulas. This event usually forces us to carry out aggressive interventions, such as anterior and posterior pelvic exenterations. However, the case records of 18 patients report that only 22 % of fistulas are produced by malignant teratoma. The following case study presents a mature cystic teratoma that fistulated the rectum and its management in our service.