Von Economo neurons: Cellular specialization of human limbic cortices?

Von Economo neurons (VENs) have been mentioned in the medical literature since the second half of the 19th century; however, it was not until the second decade of the 20th century that their cytomorphology was described in detail. To date, VENs have been found in limbic sectors of the frontal, temporal and insular lobes. In humans, their density seems to decrease in the caudo-rostral and ventro-dorsal direction; that is, from the anterior regions of the cingulate and insular cortices towards the frontal pole and the superior frontal gyrus. Several studies have provided similar descriptions of the shape of the VEN soma, but the size of the soma varies from one cortical region to another. There is consensus among different authors about the selective vulnerability of VENs in certain pathologies, in which a deterioration of the capacities involved in social behaviour is observed. In this review, we propose that the restriction of VENs towards the sectors linked to limbic information processing in Homo sapiens gives them a possible functional role in relation to the structures in which they are located. However, given the divergence in characteristics such as location, density, size and biochemical profile among VENs of different cortical sectors, the activities in which they participate could allow them to partake in a wide spectrum of neurological functions, including autonomic responses and executive functions.

The Impact of Field Courses on Undergraduate Knowledge, Affect, Behavior, and Skills: A Scoping Review.

Field courses provide transformative learning experiences that support success and improve persistence for science, technology, engineering, and mathematics majors. But field courses have not increased proportionally with the number of students in the natural sciences. We conducted a scoping review to investigate the factors influencing undergraduate participation in and the outcomes from field courses in the United States. Our search yielded 61 articles, from which we classified the knowledge, affect, behavior, and skill-based outcomes resulting from field course participation. We found consistent reporting on course design but little reporting on demographics, which limits our understanding of who takes field courses. Cost was the most commonly reported barrier to student participation, and knowledge gains were the most commonly reported outcome. This scoping review underscores the need for more rigorous and evidence-based investigations of student outcomes in field courses. Understanding how field courses support or hinder student engagement is necessary to make them more accessible to all students.

Ant-plant mutualism: a dietary by-product of a tropical ant's macronutrient requirements.

Many arboreal ants depend on myrmecophytic plants for both food and shelter; in return, these ants defend their host plants against herbivores, which are often insects. Ant-plant and other mutualisms do not necessarily involve the exchange of costly rewards or services; they may instead result from by-product benefits, or positive outcomes that do not entail a cost for one or both partners. Here, we examined whether the plant-ant Allomerus octoarticulatus pays a short-term cost to defend their host plants against herbivores, or whether plant defense is a by-product benefit of ant foraging for insect prey. Because the food offered by ant-plants is usually nitrogen-poor, arboreal ants may balance their diets by consuming insect prey or associating with microbial symbionts to acquire nitrogen, potentially shifting the costs and benefits of plant defense for the ant partner. To determine the effect of ant diet on an ant-plant mutualism, we compared the behavior, morphology, fitness, stable isotope signatures, and gaster microbiomes of A. octoarticulatus ants nesting in Cordia nodosa trees maintained for nearly a year with or without insect herbivores. At the end of the experiment, ants from herbivore exclosures preferred protein-rich baits more than ants in the control (i.e., herbivores present) treatment. Furthermore, workers in the control treatment were heavier than in the herbivore-exclusion treatment, and worker mass predicted reproductive output, suggesting that foraging for insect prey directly increased ant colony fitness. The gaster microbiome of ants was not significantly affected by the herbivore exclusion treatment. We conclude that the defensive behavior of some phytoecious ants is a by-product of their need for external protein sources; thus, the consumption of insect herbivores by ants benefits both the ant colony and the host plant.

Autoimmune hepatitis and primary sclerosing cholangitis in children and adolescents.

UNLABELLED: Clinical presentation and histopathology of autoimmune hepatitis (AIH) and primary sclerosing cholangitis (PSC) overlap syndrome (OS) are similar, but their management is different. We conducted a pediatric retrospective cross-sectional study of 34 patients with AIH and PSC. AIH had female predominance (74%) and was lower in PSC (45%). There was a trend toward higher frequency of blacks in PSC/OS (55%) compared to Caucasians (36%) and Hispanics (9%), but not race differences in AIH. Inflammatory bowel disease (IBD) was present in 75% of PSC/OS. Plasma cells were not specific for AIH (found in 42% of PSC). Concentric fibrosis was not reliable for PSC as was found in 46% of AIH. CONCLUSION: A combination of clinical history, laboratory tests, imaging studies and liver biopsy are required to confirm and properly treat AIH and PSC. Liver biopsy should be used to grade severity and disease progression, but cannot be used alone to diagnose these conditions.

Integrating clinical research in an operative screening and diagnostic breast imaging department: First experience, results and perspectives using microwave imaging.

Rationale and objectives: Clinical research is crucial for evaluating new medical procedures and devices. It is important for healthcare units and hospitals to minimize the disruptions caused by conducting clinical studies; however, complex clinical pathways require dedicated recruitment and study designs.This work presents the effective introduction of novel microwave breast imaging (MBI), via MammoWave apparatus, into the clinical routine of an operative screening and diagnostic breast imaging department for conducting a multicentric clinical study. Materials and methods: Microwave breast imaging, using MammoWave apparatus, was performed on volunteers coming from different clinical pathways. Clinical data, comprising demographics and conventional radiologic reports (used as reference standard), was collected; a satisfaction questionnaire was filled by every volunteer. Microwave images were analyzed by an automatic clinical decision support system, which quantified their corresponding features to discriminate between breasts with no relevant radiological findings (NF) and breasts with described findings (WF). Results: Conventional breast imaging (DBT, US, MRI) and MBI were performed and adapted to assure best clinical practices and optimum pathways. 180 volunteers, both symptomatic and asymptomatic, were enrolled in the study. After microwave images' quality assessment, 48 NF (15 dense) and 169 WF (88 dense) breasts were used for the prospective study; 48 (18 dense) breasts suffered from a histology-confirmed carcinoma. An overall sensitivity of 85.8 % in breasts lesions' detection was achieved by the microwave imaging apparatus. Conclusion: An optimum recruitment strategy was implemented to assess MBI. Future trials may show the clinical usefulness of microwave imaging, which may play an important role in breast screening.

Dielectric Characterization of Breast Biopsied Tissues as Pre-Pathological Aid in Early Cancer Detection: A Blinded Feasibility Study.

Dielectric characterization has significant potential in several medical applications, providing valuable insights into the electromagnetic properties of biological tissues for disease diagnosis, treatment planning, and monitoring of therapeutic interventions. This work presents the use of a custom-designed electromagnetic characterization system, based on an open-ended coaxial probe, for discriminating between benign and malignant breast tissues in a clinical setting. The probe's development involved a well-balanced compromise between physical feasibility and its combined use with a reconstruction algorithm known as the virtual transmission line model (VTLM). Immediately following the biopsy procedure, the dielectric properties of the breast tissues were reconstructed, enabling tissue discrimination based on a rule-of-thumb using the obtained dielectric parameters. A comparative analysis was then performed by analyzing the outcomes of the dielectric investigation with respect to conventional histological results. The experimental procedure took place at Complejo Hospitalario Universitario de Toledo-Hospital Virgen de la Salud, Spain, where excised breast tissues were collected and subsequently analyzed using the dielectric characterization system. A comprehensive statistical evaluation of the probe's performance was carried out, obtaining a sensitivity, specificity, and accuracy of 81.6%, 61.5%, and 73.4%, respectively, compared to conventional histological assessment, considered as the gold standard in this investigation.

The direct and ecological costs of an ant-plant symbiosis.

How strong is selection for cheating in mutualisms? The answer depends on the type and magnitude of the costs of the mutualism. Here we investigated the direct and ecological costs of plant defense by ants in the association between Cordia nodosa, a myrmecophytic plant, and Allomerus octoarticulatus, a phytoecious ant. Cordia nodosa trees produce food and housing to reward ants that protect them against herbivores. For nearly 1 year, we manipulated the presence of A. octoarticulatus ants and most insect herbivores on C. nodosa in a full-factorial experiment. Ants increased plant growth when herbivores were present but decreased plant growth when herbivores were absent, indicating that hosting ants can be costly to plants. However, we did not detect a cost to ant colonies of defending host plants against herbivores. Although this asymmetry in costs suggests that the plants may be under stronger selection than the ants to cheat by withholding investment in their partner, the costs to C. nodosa are probably at least partly ecological, arising because ants tend scale insects on their host plants. We argue that ecological costs should favor resistance or traits other than cheating and thus that neither partner may face much temptation to cheat.

A Guide to Implementing Inclusive and Accessible Virtual Poster Sessions.

Poster sessions are an integral part of conferences because they facilitate networking opportunities and provide a platform for researchers at every career stage to present and get feedback on their work. In Spring 2020, prompted by the rapid transition of the SABER (Society for the Advancement of Biology Education Research) Summer 2020 meeting to an online format, we designed and implemented a no-cost and accessible, asynchronous, and synchronous virtual poster session. Here, we outlined our goals for hosting an inclusive virtual poster session (VPS), demonstrated how a backward design approach can facilitate effective VPS, and described our rationale for adopting an asynchronous/synchronous model using the Padlet and Zoom platforms. We shared our lessons learned to facilitate a second VPS at the SABER 2021 meeting and to assist future poster session organizers in designing engaging, inclusive, and accessible poster sessions. Virtual poster sessions have great potential to improve collaborations and science communication experiences at scientific conferences and in undergraduate classrooms.

A framework for educating and empowering students by teaching about history and consequences of bias in STEM.

Racism and bias are pervasive in society-and science, technology, engineering, and mathematics (STEM) fields are not immune to these issues. It is imperative that we educate ourselves and our students about the history and consequences of this bias in STEM, investigate the research showing bias toward marginalized groups, understand how to interpret misuses of science in perpetuating bias, and identify advances and solutions to overcome racism and bias throughout our professional and personal lives. Here, we present one model for teaching a universal course for participants of all professional stages to address these issues and initiate solutions. As very few institutions require students to enroll in courses on racism and bias in STEM or even offer such courses, our curriculum could be used as a blueprint for implementation across institutions. Ultimately, institutions and academic disciplines can incorporate this important material with more region and/or discipline specific studies of bias.

Crystallin Alpha-B Overexpression as a Possible Marker of Reactive Astrogliosis in Human Cerebral Contusions.

The pathophysiology of traumatic brain injury (TBI) has not yet been fully elucidated. Crystallin alpha-B (CRYAB) is a molecular chaperone that apparently tries to stabilize the rapid thickening of the intermediate filaments of glial fibrillary acidic protein (GFAP) during the process of reactive astrogliosis in response to TBI. Previous analyses of the gene expression profile in human brain contusion tissue showed us an exacerbated CRYAB overexpression. Here, we used 3, 3'-diaminobenzidine (DAB) immunohistochemistry and immunofluorescence to verify CRYAB overexpression and to describe its expression and distribution in samples of contused cortical tissue derived from emergency decompressive surgery after severe TBI. The histological expression of CRYAB was mainly seen in subcortical white matter astrocytes of injured tissue. Most of the cells that overexpressed GFAP in the analyzed tissue also overexpressed CRYAB, a finding corroborated by the co-localization of the two markers. The only difference was the presence of a few pyramidal neurons that expressed CRYAB in layer V of the cerebral cortex. The selective vulnerability of layer V of the cerebral cortex during TBI could explain the expression of CRYAB in neurons of this cortical layer. Our results indicate a parallel behavior in the cellular expression of CRYAB and GFAP during the subacute response to TBI. These results lead us to postulate CRYAB as a possible marker of reactive astrogliosis in contused cortical tissue.

Implementing team-based learning in the life sciences: A case study in an online introductory level evolution and biodiversity course.

Team-Based Learning (TBL) is a pedagogical tool that has great potential to develop student engagement, accountability, and equity in the online classroom. TBL is rooted in evidence-based educational theories and practices that underlie many active learning approaches such as self-testing, team discussion, and application of knowledge. The use of these approaches is associated with better student performance, retention, and sense of belonging in the classroom, aspects that are often reported to be especially lacking in online courses. Here, we describe how we implemented TBL in a face-to-face and an online introductory level evolution and biodiversity course. We implemented TBL in the face-to-face course (~200 students) starting in 2018 and in the online course (~30 students) starting in the summer of 2019. We used several online applications to facilitate the transition to an online platform such as Simbio, Slack, VoiceThread, Articulate 360, and Teammates. Our experiences using TBL approaches in the online course have been rewarding, and students are engaged and accountable for their learning and performed well in the course. Our goal is to provide an example of how we designed a life science course using TBL approaches and transitioned the course to an online environment. With the current switch to remote instruction and online learning, we recommend the use of TBL as a course design approach that can improve the students' online learning experience.

Zebularine suppressed gemcitabine-induced senescence and improved the cellular and plasma pharmacokinetics of gemcitabine, augmented by liposomal co-delivery.

Chemoresistance is a major factor driving cancer recurrence. This study investigated the potential of zebularine, a dual cytidine deaminase (CDA)/epigenetic inhibitor, to circumvent gemcitabine-resistance in pancreatic cancer using a nanomedicine co-delivery approach. The mRNA expression of key metabolic enzymes, including CDA for gemcitabine deactivation in a gemcitabine-resistant cell line Gr2000 and its parental MIA PaCa-2 was compared using quantitative reverse transcription polymerase chain reaction. A highly gemcitabine-resistant population (HRP) in Gr2000 were characterised for their growth pattern, ß-galactosidase activity (a hallmark of senescence) and chemosensitivity to zebularine after isolation. The CDA inhibition effects of zebularine on the intracellular gemcitabine accumulation and pharmacokinetics in rats when co-delivered with pH-sensitive liposomes (pSL) were investigated. Gr2000 had a 3-time upregulated mRNA expression and enzyme activity for CDA. The HRP (28% of bulk Gr2000) were predominately senescent cells which re-proliferated following a growth arrest for a week. Zebularine suppressed the regrowth of senescent cells, meanwhile enhanced cellular gemcitabine concentration by 2-fold. When co-delivered with pSL, zebularine increased cellular gemcitabine concentration by 4-fold, and extended the half-life of gemcitabine in plasma by 22-fold in rats. In conclusion, multiple mechanisms including therapy-induced senescence were identified with gemcitabine-resistance. Co-delivery of zebularine using liposomes could provide multifaceted benefits in gemcitabine therapy for pancreatic cancer treatment.

Breast cancer mortality after eight years of an improved screening program using digital breast tomosynthesis.

OBJECTIVES: To assess screening quality metrics and to describe mortality rates eight years after redesign of breast cancer screening and diagnosis pathways, and the introduction of digital breast tomosynthesis. SETTING: Breast Unit of the Toledo Health Area in the region of Castilla-La Mancha (Spain). METHODS: We recorded screening metrics and mortality data following the introduction of digital breast tomosynthesis in 2011 for screening and diagnosis pathways. We then compared the mortality between Toledo Health Area and the rest of Castilla-La Mancha, where digital breast tomosynthesis is not available. RESULTS: All screening quality metrics improved following the introduction of digital breast tomosynthesis. The cancer detection rate significantly increased from 2.3 (95% confidence interval (CI): 1.9-3.6) to 4.5 per 1000 women (95% CI: 3.2-5.2) on average between the periods 2005-2009 and 2015-2018, while the recall rate significantly decreased from 7.0% (95% CI: 6.8%-8.2%) to 2.6% (95% CI: 2.0%-3.6%). Comparing breast cancer mortality rates for 2014-2018 in the Toledo Health Area with the rest of Castilla-La Mancha, which had similar cancer treatment access and management protocols but without digital breast tomosynthesis, the crude mortality rate was 17.79 (95% CI: 15.38 -20.19) vs. 24.76 per 100,000 (95% CI: 26.12-23.39), respectively. The cumulative risk of death was also significantly lower for the Toledo Health Area than for Castilla-La Mancha. CONCLUSION: The introduction of digital breast tomosynthesis improved screening quality indicators. Breast cancer mortality simultaneously decreased with respect to the rest of Castilla-La Mancha. Further research is needed to assess the long-term results, and the role that the redesign may have played in reducing mortality.

Cochlear implant in patients with single sided deafness: hearing results and communicative benefits.

Objective: Evaluate auditory results and communicative benefits in adult patients with single-sided deafness (SSD) treated with cochlear implantation.Study Design: Observational descriptive case series.Setting: Hospital Universitario Fundación Santa Fe de Bogotá.Patients: Ten patients with profound post-lingual SSD were treated with cochlear implantation between January 2011 and March 2016. Two patients were excluded because of incomplete follow-up.Interventions: Medical records included demographic information, pre and post-operative audiometric results, and binaural and monoaural speech discrimination tests in three sound-in-noise configurationswith the cochlear implant turned on and off, respectively. Subjective improvement was evaluated using the Abbreviated Profile of Hearing Aid Benefit (APHAB) and Speech, Spatial, and Qualities of Hearing Scale (SSQ-B).Main Outcome Measures: Pre and post-operative audiometric and speech discrimination results, post-operative binaural and monoaural speech discrimination in noise results, and APHAB and SSQ-B questionnaire results.Results: Significant improvement in speech discrimination in a noisy environment was found when the noise and signal were presented from the front, and when the signal was presented to the implanted ear and the noise to the healthy ear. SSQ-B questionnaire showed improvement in all subscales, while APHAB showed improvement in all subscales except sound aversion.Conclusion: Patients with SSD showed improvement regarding communication skills and sound discrimination in a noisy environment.

Correlato neurobiológico de los síntomas premotores del parkinson: el origen en la teoría de Braak / Neurobiological correlate of parkinson's premotor symptoms: the origin in Braak's theory / Correlação neurobiológica dos sintomas pré-motores de parkinson: a origem na teoria de Braak

El diagnóstico de enfermedad de Parkinson (ED) se basa en las principales manifestaciones motoras: bradicinesia en combinación con temblor en reposo, rigidez o ambos. Cuando se realiza el diagnóstico basado en la sintomatología motora clínica típica ya se han perdido hasta el 60 % de las neuronas dopaminérgicas de la sustancia negra pars compacta mesencefálica. La identificación de los síntomas premotores son un marcador temprano para sospechar la aparición futura de la enfermedad, así como su progresión y gravedad. La hipótesis sobre la patogénesis que mejor expone la progresión de la enfermedad es la teoría de Braak. Esta se basa en la aparición y presencia de cuerpos de Lewy en diferentes estructuras anatómicas, las cuales representadas en cada uno de sus seis estadios y podrían ser la explicación biológica de los síntomas premotores, motores y no motores. La detección temprana de los síntomas premotores puede tener repercusiones positivas en el enfoque, seguimiento, diagnóstico y tratamiento de la EP. El propósito de este artículo es identificar las aproximaciones neurológicas descritas por la teoría de Braak para los síntomas premotores de la enfermedad de Parkinson de acuerdo con la literatura publicada en los últimos 20 años.

The diagnosis of Parkinson's disease (PD) is based on the main motor manifestations: bradykinesia in combination with tremor at rest, rigidity, or both. When the diagnosis is made based on typical clinical motor symptoms, up to 60 % of the dopaminergic neurons of the mesencephalic substantia nigra pars compacta have already been lost. The identification of premotor symptoms is an early marker to suspect the future appearance of the disease, as well as its progression and severity. The hypothesis about the pathogenesis that best exposes the progression of the disease is Braak's theory. It is based on the appearance and presence of Lewy bodies in different anatomical structures, which are represented in each of its six stages and could be the biological explanation biological of premotor, motor, and non-motor symptoms. Early detection of premotor symptoms can have positive repercussions in the approach, follow-up, diagnosis and treatment of PD. The purpose of this article is to identify the neurological approaches described by Braak's theory for the premotor symptoms of Parkinson's disease according to the literature published in the last 20 years.

O diagnóstico da doença de Parkinson (DP) baseia-se nas principais manifestações motoras: bradicinesia combinada com tremor de repouso, rigidez ou ambos. Quando o diagnóstico é feito com base em sintomas clínicos motores típicos, até 60% dos neurônios dopaminérgicos da substância negra pars compacta mesencefálica já foram perdidos. A identificação de sintomas pré-motores é um marcador precoce para suspeitar do futuro aparecimento da doença, bem como da sua progressão e gravidade. A hipótese sobre a patogênese que melhor expõe a progressão da doença é a teoria de Braak. Isto se baseia no aparecimento e presença de corpos de Lewy em diferentes estruturas anatômicas, que estão representados em cada uma de suas seis etapas e podem ser a explicação biológica dos sintomas pré-motores, motores e não motores. A detecção precoce de sintomas pré-motores pode repercutir positivamente na abordagem, acompanhamento, diagnóstico e tratamento da DP. O objetivo deste artigo é identificar as abordagens neurológicas descritas pela teoria de Braak para os sintomas pré-motores da doença de Parkinson de acordo com a literatura publicada nos últimos 20 anos.

Diagnostic value of halo sign in young women (aged 45 to 49 years) in a breast screening programme with synthesized 2D mammography.

OBJECTIVE:: To assess the clinical performance of the halo sign in tomosynthesis and synthesized 2D mammography, and to identify age groups where its diagnostic value may be greater. METHODS:: 183 patients with nodules were recalled from the breast screening programme (with tomosynthesis and 2D synthesized mammograms). The patients were separated into two groups, 45-49 years and 50-69 years, and depending on the presence or not of halo sign. We calculated the predictive values for the different age groups. RESULTS:: In 45-49 years group, 86 nodular lesions were recalled, 66 (76.7%) with positive halo sign and 20 (23.3%) with negative halo sign. In positive halo sign group, biopsy was considered in 23 (34.8%), with histological features of benignity. In 50-69 years group, 98 nodular lesions from 97 patients were recalled, 51 (52%) with positive halo sign and 47 (48%) with negative halo sign. In positive halo sign group, biopsy was considered in 13 (25.5%); four (30.8%) were malignant and nine (69.2%) were benign. CONCLUSION:: Halo sign could be considered as a marker of benign lesion in females < 50 years. In females ≥ 50 years, other breast imaging techniques should be considered, with or without histological studies, to rule out malignancy. ADVANCES IN KNOWLEDGE:: The trend of a positive halo sign to act as a marker of benign lesion could be improve the recall rate and positive predictive values in the breast screening programme with tomosynthesis and synthesized 2D mammography, especially in young females.

Consenso para el manejo práctico de la urticaria en atención primaria

Introduction: urticaria has a high impact on the quality of life of patients with this condition. While there are multiple evidence-based guidelines, these tend to be aimed at providing management recommendations for specialists rather than primary care physicians, who are usually the first to care for patients with urticaria. Objective: to develop a consensus document aimed at presenting evidence-based recommendations to help general practitioners, family doctors, pediatricians, internists and emergency physicians provide timely care for patients with urticaria, facilitating its diagnosis and timely care, and thus avoiding delays for the patients. Methods: international urticaria guidelines with recommendations based on the GRADE system were used as the source of information. Delegates of the interested scientific societies were convened, and, through structured meetings, treatment barriers and possible solutions for the application of the recommendations in primary care were identified. Results: the main barriers for primary care physicians in applying the guidelines were identified: confusion in the diagnosis, proper timing of treatment, first-line medications, and management of special situations. Possible consensus solutions were proposed for each identified barrier. Conclusion: this consensus document contains recommendations for the management and treatment of acute and chronic urticaria which help primary care physicians provide timely and effective treatment for patients with this disease. (Acta Med Colomb 2022; 48. DOI:https://doi.org/10.36104/amc.2023.2722).

[Intelligence quotient loss in Mexican pottery artisan's children]. / Pérdida de coeficiente intelectual en hijos de alfareros mexicanos.

BACKGROUND: In Mexico, artisans frequently use lead oxide or greta in order to produce utensils, which are destined to preparation and storage of food and drinks. Additionally, the risk of lead poisoning of artisans and their families is greater than in general population, and within these families, children are the most susceptible to lead poisoning. The aim of this study was to estimate IQ loss in Mexican children from potter families exposed to lead. METHODS: Lead concentrations in soil were determined in 19 potter's homes that functioned as pottery workshops in seven Mexican states between 2009 and 2012. This information was used to estimate blood lead levels through the integrated exposure uptake biokinetic (IEUBK) model. The loss of IQ points was then estimated according to the Lanphear and Schwartz models. RESULTS: The mean lead concentration found in the workshops' soil was 1098.4 ppm. Blood lead levels estimated in children under 8 years old were 26.4 µg/dL and the loss of IQ points comprised from 7.13 to 8.84 points depending on the model. CONCLUSIONS: It is possible that 11 children from families of artisans in Mexico may be losing between 7.13 to 8.84 IQ points, due to lead exposure in their houses-workshops. This loss in IQ points could have important health, economic and social impacts.

Introducción: en México, los alfareros continúan usando frecuentemente el óxido de plomo o greta para producir utensilios, los cuales se destinan a la preparación y almacenamiento de alimentos y bebidas. Adicionalmente, el riesgo de intoxicación por plomo de los alfareros y sus familias es mayor que en la población general, y en tales familias, los niños son los más susceptibles a la intoxicación por plomo. El objetivo del estudio fue estimar la pérdida de puntos de coeficiente intelectual (CI) en hijos de alfareros mexicanos expuestos al plomo. Métodos: durante el periodo de 2009 a 2012 se determinaron las concentraciones de plomo en suelo de 19 casas-talleres de alfareros en siete estados mexicanos. Esta información se utilizó para estimar el nivel de plomo en sangre, por medio del modelo biocinético integrado de absorción por exposición (IEUBK, por sus siglas en inglés). Posteriormente, se calcularon los puntos perdidos de CI según los modelos de Schwartz y Lanphear. Resultados: la concentración promedio de plomo en suelo fue de 1098.4 ppm. Se estimó un nivel de plomo en sangre de 26.4 µg/dL para menores de 8 años. La pérdida de puntos de CI estimada fue 7.13 y 8.84, según el modelo utilizado. Conclusión: es posible que al menos 11 niños de familias alfareras mexicanas estén perdiendo entre 7.13 y 8.84 puntos de CI, debido a la exposición al plomo en sus casas-talleres, lo que supone importantes impactos económicos, sociales y de salud.

Síndrome de Guillain-Barré postinfección por SARS-CoV-2 y postvacunación contra covid-19: una revisión sistemática de casos / Guillain-Barré syndrome post-SARS-CoV-2 infection and post-vaccination against COVID-19: a systematic review of cases

RESUMEN INTRODUCCIÓN: El síndrome de Guillain-Barré (SGB) se ha asociado recientemente con la infección por SARS-CoV-2 y su vacunación. El objetivo de esta revisión es describir los datos sociodemográficos y la presentación clínica del SGB asociado con la infección y la vacunación contra covid--19. MATERIALES Y MÉTODOS: Se realizó una búsqueda sistemática en las bases de datos Medline, Embase y LILACS. Se incluyeron reportes de casos publicados entre los años 2021 y 2022. De los artículos seleccionados se extrajo edad, sexo, comorbilidades, laboratorio de la vacuna, tiempo de inicio de síntomas, manifestaciones clínicas, método diagnóstico, tratamiento recibido y desenlace. RESULTADOS: Se seleccionaron 93 artículos, en los que se reporta un total de 131 casos: 82 asociados con la infección por SARS-CoV-2 y 49 asociados con la vacunación contra el covid-19. La población más afectada fue el sexo masculino y se encontró entre los 31 y los 65 años. Las principales manifestaciones descritas fueron: paresia de extremidades, compromiso de la sensibilidad, arreflexia, compromiso de los pares craneales. DISCUSIÓN: El cuadro clínico del SGB presentó características similares a la presentación clásica. La disautonomía y la falla respiratoria son las principales complicaciones mortales de esta entidad. CONCLUSIÓN: El SGB se puede presentar de manera postinfecciosa o parainfecciosa. Se debe sospechar cuando se consulta por cuadro clínico de neuropatía desmielinizante con antecedentes de inmunización o síntomas concomitantes sugestivos de covid-19. Se necesitan más estudios para establecer una asociación entre el virus y el SGB.

ABSTRACT INTRODUCTION: Guillain-Barre syndrome (GBS) has recently been associated with SARS-CoV-2 infection and vaccination. The objective of this review is to describe the sociodemographic data and the clinical presentation of GBS associated with infection and vaccination against COVID-19. MATERIALS AND METHODS: A systematic search was performed in the Medline, Embase and LILACS databases. Case reports published in 2021-2022 are included. From the selected articles, age, sex, comorbidi-ties, vaccine brand, symptom onset time, clinical manifestations, diagnostic method, treatment received and outcome were extracted. RESULTS: 93 articles were selected, reporting a total of 131 cases: 82 associated with SARS-CoV-2 infection and 49 associated with vaccination against COVID-19. The most affected population was the male sex and was between 31 and 65 years old. The main manifestations described were: limb paresis, compromised sensitivity, areflexia, compromised cranial nerves. DISCUSSION: The clinical picture of GBS presented characteristics similar to the classic presentation. Dys-autonomia and respiratory failure are the main fatal complications of this entity. CONCLUSION: GBS can present in a postinfectious, parainfectious manner. It should be suspected when consulting for a clinical picture of demyelinating neuropathy with a history of immunization or concomitant symptoms suggestive of COVID-19. More studies are needed to establish an association between the virus and GBS.

DNA barcoding of Jamaican bats: implications to Neotropical biodiversity.

We report on the first comprehensive DNA barcoding survey of bats from Jamaica and compare the genetic variation to similar species on South America and Central America. Bats comprise the majority of mammalian diversity in typical lowland forest in the Neotropics, but the Caribbean is one noticeable geographic gap in the International Barcode of Life reference database. Of the 20 known species reported from Jamaica, half were DNA barcoded and were genetically distinct with interspecific variation ranging from 17 to 33%. By contrast, intraspecific variation ranged from 0 to 0.5% indicating that the barcode gap was sufficient in differentiating bat species diversity in Jamaica. The low levels of intraspecific divergence indicate that the populations within each species are relatively homogeneous across the island. There were, however, several cases of high sequence divergence for widely distributed species that occur on both the Caribbean islands and the continental mainland, which warrant further taxonomic study.