COVID-19 safety leadership, perceived severity, and emotional exhaustion: Does safety culture matter?

INTRODUCTION: Emotional exhaustion is a major health-related issue that employees face, especially during crises such as pandemics. This study seeks to understand how safety leadership applied to the COVID-19 pandemic relates to emotional exhaustion, and to examine its mechanisms (i.e., perceived severity) along with its boundary condition (i.e., safety culture). METHOD: A time lag study was conducted to collect data from 229 employees working in the service industry in Morocco. Data were analyzed through the Partial Least Squares Structural Equation Modeling (PLS-SEM) technique using SmartPLS 4. RESULTS: The results demonstrate that safety leadership is negatively related to emotional exhaustion. Additionally, they suggest that the relationship between COVID-19 safety leadership and perceived severity depends on the level of the moderating variable (i.e., safety culture). Specifically, the relationship is positive when safety culture is low, but is negative when safety culture is high. PRACTICAL APPLICATIONS: The results of this study are important as they extend our knowledge of the nature of safety leadership and emotional exhaustion, and offer managers practical implications that can help to optimize safety leadership practices.

Keeping your cool: thermoregulatory performance and plasticity in desert cricetid rodents.

Small mammals in hot deserts often avoid heat via nocturnality and fossoriality, and are thought to have a limited capacity to dissipate heat using evaporative cooling. Research to date has focused on thermoregulatory responses to air temperatures (Ta) below body temperature (Tb). Consequently, the thermoregulatory performance of small mammals exposed to high Ta is poorly understood, particularly responses across geographic and seasonal scales. We quantified the seasonal thermoregulatory performance of four cricetid rodents (Neotoma albigula, Neotoma lepida, Peromyscus eremicus, Peromyscus crinitus) exposed to high Ta, at four sites in the Mojave Desert. We measured metabolism, evaporative water loss and Tb using flow-through respirometry. When exposed to Ta≥Tb, rodents showed steep increases in Tb, copious salivation and limited evaporative heat dissipation. Most individuals were only capable of maintaining Ta-Tb gradients of ∼1°, resulting in heat tolerance limits (HTLs) in the range Ta=43-45°C. All species exhibited a thermoneutral Tb of ∼35-36°C, and Tb increased to maximal levels of ∼43°C. Metabolic rates and rates of evaporative water loss increased steeply in all species as Ta approached Tb. We also observed significant increases in resting metabolism and evaporative water loss from summer to winter at Ta within and above the thermoneutral zone. In contrast, we found few differences in the thermoregulatory performance within species across sites. Our results suggest that cricetid rodents have a limited physiological capacity to cope with environmental temperatures that exceed Tb and that a rapidly warming environment may increasingly constrain their nocturnal activity.

Plump endothelial cells integrated into pre-existing venules contribute to the formation of 'mother' and 'daughter' vessels in pyogenic granuloma: possible role of galectin-1, -3 and -8.

INTRODUCTION: Pyogenic granuloma (PG) is a reactive inflammatory vascular lesion of the skin and mucous membranes, characterised by the presence of enlarged venules and seamed and seamless capillaries with plump endothelial cells (EC), and numerous macrophages. EC activation upregulates the synthesis of galectins and induces their translocation to the EC surface promoting angiogenesis and lymphangiogenesis, particularly galectin-1 (Gal-1), Gal-3 and Gal-8. However, the presence and distribution of Gal-1, -3 and -8, as well as their implications in the pathogenesis of PG, has not been considered. MATERIALS AND METHODS: Eight biopsies from patients diagnosed with PG were selected. The presence of PECAM-1/CD31, IL-1ß, VEGF-C, VEGFR-2, VEGFR-3, integrin ß1, CD44, fibronectin and Gal-1, -3 and -8 was assessed by immunofluorescence staining using confocal laser scanning microscopy. RESULTS AND DISCUSSION: Immunostaining revealed that these molecules were present in the enlarged venules with plump ECs, in some macrophages and other immune cells. We propose that macrophages release VEGF-A and VEGF-C inducing VEGFR-2/VEGFR-3 expression and activation, leading macrophages to transdifferentiate into plump ECs that might integrate into pre-existing venules, contributing to the formation of enlarged venules with transluminal bridges and capillaries. EC activation, induced by certain cytokines, has been shown to stimulate galectin expression and changes in the cellular localisation through association and activation of specific EC surface glycoproteins. Therefore, it is plausible that Gal-1, -3 and -8, acting in a concerted manner, could be mediating the transdifferentiation of macrophages into plump ECs and facilitating their migration and incorporation into the new vessels. LAY SUMMARY: In this study, immunostaining of pyogenic granuloma (PG) tissue sections showed immunoreactivity for PECAM-1/CD31, IL-1ß, VEGF-C, VEGFR-2 and VEGFR-3, and galectin-1, -3 and -8 in enlarged venules with plump endothelial cells (EC), as well as in some macrophages and other immune cells. Interestingly, enlarged and thin-walled transient vessels lined by PECAM-1/CD31 and VEGFR-2 immunopositive ECs that form from pre-existing normal venules in response to VEGF-A (called 'mother' vessels [MV]) and that undergo intraluminal bridging evolving into various types of capillaries (called 'daughter' vessels [DV]) have been observed in benign and malignant tumours, in physiological and pathological angiogenesis as well as in vascular malformations, suggesting an important role for VEGF-A and VEGFR-2 in such a process. However, it is not only the mechanisms by which the MVs evolve in different types of DVs that remains to be elucidated, but also whether the cells that form intraluminal bridges proceed from locally activated ECs or whether they are derived from bone marrow precursors or from resident macrophages.Given that the formation of homodimers by Gal-1 and Gal-8 and pentamers by Gal-3 to generate gal-glycan lattices at the cell surface and in the extracellular space has been shown, it is possible that in PG tissue Gal-1, -3 and -8, through their binding partners, form a supramolecular structure at the surface of ECs and plump ECs, macrophages and in the extracellular space that might be mediating the transdifferentiation of macrophages into plump ECs and facilitating the migration and incorporation of these cells into the pre-existing venules, thus contributing to the formation of MVs and DVs.

Evaluación del riesgo suicida y caracterización de factores asociados en estudiantes de medicina colombianos

Objetivo: estimar la prevalencia de riesgo suicida en estudiantes de medicina colombianos y caracterizar factores de riesgo conocidos en dicha población. Metodología: estudio de tipo corte transversal en estudiantes de medicina de diez universidades colombianas. El riesgo suicida se estimó con la escala de Plutchik. Se utilizó un cuestionario autoaplicado, realizando muestreo por conveniencia. El análisis estadístico se realizó con SPSS 5.0. Resultados: 243 sujetos, con edad entre 15-27 años, 64,5 % eran mujeres, 16 % cursaban internado; 3,3 % tuvo autopercepción de mal rendimiento académico, 16 % reportó antecedente personal y 23 % antecedente familiar de enfermedad mental; 18,8 % tenían consumo de licor mayor al social. La prevalencia general de riesgo suicida fue de 49,4 %, se encontró asociación entre el riesgo suicida y el antecedente personal de enfermedad mental (p= 0,000; OR= 3,01 IC: 1,60-5,63) y la autopercepción de mal rendimiento académico (p= 0,001; OR= 2,32 IC: 2,008-2,696). Conclusión: este estudio refuerza la necesidad de la búsqueda activa del riesgo suicida en estudiantes de medicina.

Tamaño y porciones del consumo de alimentos de la población: disponibilidad de información actualizada / Size and portions of the population's food consumption: availability of updated information

El objetivo de este estudio fue identificar la producción científica y el comportamiento relacionado al tamaño y porción del consumo de alimentos de la población. Se seleccionó 110 artículos relacionados al tema de la base de datos Scopus, a través, de operadores lógicos, AND entre palabras y OR entre sinónimos. La revista Appetive obtuvo 117 citas. Los artículos publicados corresponden a 64 con autoría de más de tres autores. La mayor producción científica fue en el año 2016 con 37 publicaciones. En todos los artículos revisados no existe información sobre el tamaño y porción en gramos, ni en medida casera adecuada para el consumo. Esta propuesta de revisión permitirá desarrollar futuras investigaciones para precisar el tamaño y porción adecuada según estado fisiológico y grupo etario.

The objective of this study was to identify the scientific production and its behavior related to the size and servings of the population's food consumption. It was selected 110 articles related to the topic from the Scopus database, through logical operators, AND among words and OR among synonyms. The Appetive magazine obtained 117 citations. The published articles correspond to 64 with authorship of more than three authors. The largest scientific production was in 2016 with 37 publications. In all the articles reviewed, there is no information on the size and servings in grams, nor in the home measure suitable for consumption. This revision proposal will allow the development of future research to determine the appropriate size and servings according to physiological status and age group.

Galectin-1 and Galectin-3 and Their Potential Binding Partners in the Dermal Thickening of Keloid Tissues.

Keloids are defined histopathologically as an inflammatory disorder characterized by exhibiting numerous fibroblasts, abnormal vascularization, increased number of proinflammatory immune cells as well as uncontrolled cell proliferation, and exacerbated and disorganized deposition of extracellular matrix (ECM) molecules. Importantly, many of these ECM molecules display N- and O-linked glycan residues and are considered as potential targets for galectin-1 (Gal-1) and galectin-3 (Gal-3). Nevertheless, the presence and localization of Gal-1 and Gal-3 as well as the interactions with some of their binding partners in keloid tissues have not been considered. Here, we show that in the dermal thickening of keloids, versican, syndecan-1, fibronectin, thrombospondin-1, tenascin C, CD44, integrin ß1, and N-cadherin were immunolocalized in the elongated fibroblasts that were close to the immune cell infiltrate, attached to collagen bundles, and around the microvasculature and in some immune cells. We also show that Gal-1 and Gal-3 were present in the cytoplasm and along the cell membrane of some fibroblasts and immune and endothelial cells of the dermal thickening. We suggest that Gal-1 and Gal-3, in concert with some of the ECM molecules produced by fibroblasts and by immune cells, counteract the inflammatory response in keloids. We also proposed that Gal-1 and Gal-3 through their binding partners may form a supramolecular structure at the cell surface of fibroblasts, immune cells, endothelial cells, and in the extracellular space that might influence the fibroblast morphology, adhesion, proliferation, migration, and survival as well as the inflammatory responses.

Comparison of Psychological and Physiological Responses to Imposed vs. Self-selected High-Intensity Interval Training.

Kellogg, E, Cantacessi, C, McNamer, O, Holmes, H, von Bargen, R, Ramirez, R, Gallagher, D, Vargas, S, Santia, B, Rodriguez, K, and Astorino, TA. Comparison of psychological and physiological responses to imposed vs. self-selected high-intensity interval training. J Strength Cond Res 33(11): 2945-2952, 2019-High-intensity interval training elicits similar physiological adaptations as moderate intensity continuous training (MICT). Some studies report greater enjoyment to a bout of high-intensity interval exercise (HIIE) vs. MICT, which is surprising considering that HIIE is more intense and typically imposed on the participant. This study compared physiological and perceptual responses between imposed and self-selected HIIE. Fourteen adults (age = 24 ± 3 years) unfamiliar with HIIE initially performed ramp exercise to exhaustion to measure maximal oxygen uptake (VO2max) followed by 2 subsequent sessions whose order was randomized. Imposed HIIE consisted of eight 60 seconds bouts at 80 percent peak power output (%PPO) separated by 60 seconds recovery at 10 %PPO. Self-selected HIIE (HIIESS) followed the same structure, but participants freely selected intensity in increments of 10 %PPO to achieve a rating of perceived exertion (RPE) ≥7. During exercise, heart rate, VO2, blood lactate concentration (BLa), affect (+5 to -5), and RPE were assessed. Physical Activity Enjoyment Scale was measured after exercise. Results showed higher VO2 (+10%, p = 0.013), BLa (p = 0.001), and RPE (p = 0.001) in HIIESS vs. HIIEIMP, and lower affect (p = 0.01), and enjoyment (87.6 ± 15.7 vs. 95.7 ± 11.7, p = 0.04). There was a significantly higher power output in self-selected vs. imposed HIIE (263.9 ± 81.4 W vs. 225.2 ± 59.6 W, p < 0.001). Data suggest that intensity mediates affective responses rather than the mode of HIIE performed by the participant.

Deficiencia de fenilalanina hidroxilasa: espectro clínico y estado actual del diagnóstico en colombia / Phenylalanine hydroxylase deficiency: clinical spectrum and current diagnosis in colombia

RESUMEN Las mutaciones del gen PAH generan deficiencia de la enzima fenilalanina hidroxilasa. Su actividad final varía desde una actividad casi nula o indetectable en la fenilcetonuria clásica hasta una actividad residual del 10 al 35% de la normal. Esta alteración corresponde al error innato del metabolismo de los aminoácidos más frecuente, afectando a 1 de cada 10.000 personas. Las diferentes cantidades de fenilalanina en sangre se traducen en un espectro amplio de manifestaciones clínicas que incluyen retraso global del desarrollo, discapacidad intelectual, convulsiones, rasgos autistas y comportamiento agresivo en los casos más graves. El diagnóstico temprano a través de los programas de tamizaje neonatal se considera prioritario pues las intervenciones oportunas evitan el daño del sistema nervioso central. Conclusiones: El diagnóstico en Colombia es tardío, las intervenciones realizadas a partir de ese momento son fútiles pues el deterioro cognitivo es irreparable, por lo tanto es imperativa la realización de pruebas diagnósticas tempranas cuando aún las intervenciones médicas pueden impactar la mejoría clínica del paciente con disminución importante de la morbilidad propia de esta patología, convirtiéndose en una necesidad la ampliación del programa de tamizaje neonatal, el cual estaría amparado bajo la ley colombiana de enfermedades huérfanas.

ABSTRACT Mutations in the PAH gene generate phenylalanine hydroxylase enzyme deficiency. Its final activity varies from almost null or undetectable in classical phenylketonuria to a residual activity of 10 to 35% of normal activity. This alteration corresponds to the innate more frequent error of the metabolism of the amino acids, affecting 1 of every 10,000 people. Different amounts of phenylalanine in blood translate into a broad spectrum of clinical manifestations including global developmental delay, intellectual disability, seizures, autistic traits, and aggressive behavior in the most severe cases. Early diagnosis through neonatal screening programs is considered a priority because timely interventions avoid damage to the central nervous system. Conclusions: The diagnosis in Colombia is belated, the interventions made from that moment are futile because the cognitive deterioration is irreparable. Therefore, it is imperative to carry out early diagnostic tests when medical interventions can still impact the clinical improvement of the patient with an important decrease of the morbidity characteristic of this pathology, making it necessary to expand the neonatal screening program which would be protected under the Colombian law of orphan diseases.

Mucin1 expression in focal epidermal dysplasia of actinic keratosis.

BACKGROUND: Actinic keratoses (AKs) are generally considered as premalignant skin lesions that can progress into squamous cell carcinoma (SCC) in situ and invasive SCC. However, its progression to SCC is still matter of debate. A transmembrane glycoprotein that contributes to the progression of certain premalignant and malignant lesions is mucin1 (MUC1). Nevertheless, their functions in the skin lesions are not yet fully clear. Therefore, the aim of this study is to ascertain whether MUC1 is present in the focal epidermal dysplasia of AK. METHODS: Fourteen skin biopsies from patients diagnosed with AK were selected. They were classified according to the degree of dysplasia in keratinocyte intraepidermal neoplasia (KIN) I, KIN II, and KIN III. In five biopsies the three degrees were present, in two biopsies both KIN I and KIN II, in four biopsies only KIN I, and in three biopsies only KIN III. The presence of MUC1 was assessed by immunofluorescence staining using confocal laser scanning microscopy. RESULTS: Immunostaining revealed that MUC1 was present over the entire cell surface of only a few atypical basal keratinocytes confined to the lower third of the epidermis (KIN I). While in KIN II where atypical keratinocytes occupy the lower two thirds, MUC1 was localized at the apical surface of some atypical keratinocytes and over the entire cell surface of some of them. Interestingly, in KIN III where the atypical keratinocytes extend throughout the full thickness, MUC1 was localized at the apical surface and over the entire cell surface of many of these cells. Conversely, MUC1 expression was not detected in the epidermis of normal skin. CONCLUSIONS: Our findings suggest that the expression of MUC1 in AK would be induced by alteration of keratinocyte stratification and differentiation and associated to the degree of dysplasia rather than the thickness of the epidermis.

Presence of MUC1 in the epidermal thickening of psoriatic plaques.

Mucin 1 (MUC1) is a transmembrane glycoprotein that protects epithelial cells from injury caused by external stimuli. In addition to this role, MUC1 is involved in cell-cell adhesion, proliferation, motility, invasion and survival. In epithelial cells, MUC1 expression is regulated by binding of TNFα to TNFR1 and activation of the NFκB pathway. In human skin, MUC1 is not expressed in normal epidermis but rather in pre-malignant and malignant conditions. Nevertheless, the expression of MUC1 and its implication in psoriasis vulgaris has not been considered. Here, we show that MUC1 was present in the epidermis of psoriatic plaques observed in 11 biopsies from patients diagnosed with psoriasis vulgaris which were compared with 5 normal human skin. Interestingly, MUC1 in addition to being localized at the apical surface of some suprabasal keratinocytes, was also localized over the entire cell surface of some of these cells and some basal keratinocytes. Conversely, no MUC1 immunoreactivity was detected in the epidermis of normal skin. Additionally, we demonstrated that activated TNFR1, c-Src, IKKα/ß and p50/p65 were present in the epidermal thickening. This study demonstrates the presence of MUC1 in psoriatic plaque and suggests a possible role for MUC1 during the motility, migration and survival of human keratinocytes, where activated TNFR1, c-Src and NFκB seem to be required.

Posicionamiento sobre el entrenamiento de fuerza en jóvenes. Consenso Internacional de 2014 / Position statement on youth resistance training: the 2014 International Consensus

El manuscrito actual es la traducción del Posicionamiento sobre el Entrenamiento de Fuerza para Jóvenes: el Consenso Internacional de 2014. El consenso original es a su vez una adaptación del posicionamiento de la United Kingdom Strength and Conditioning Association. Ha sido revisado y respaldado por organizaciones profesionales relevantes en los campos de la medicina del deporte, la ciencia de la actividad física y la pediatría. Los autores de este articulo fueron seleccionados entre los campos de la ciencia del ejercicio pediátrico, la medicina pediátrica, la educación física, la preparación física y la medicina del deporte. El manuscrito fue publicado originalmente en el British Journal of Sports Medicine y representa el documento final ratificado oficialmente a nivel ejecutivo por cada organización que lo respalda. Para enlazar con la versión original del manuscrito en ingles diríjanse a: http://bjsm.bmj.com/content/early/2013/09/20/bjsports-2013-092952.full

The current manuscript is a translation of the Position statement on youth resistance training: the 2014 International Consensus. The original manuscript was adapted from the oficial position statement of the UK Strength and Conditioning Association on youth resistance training. It was subsequently reviewed and endorsed by leading professional organisations within the fields of sports medicine, exercise science and paediatrics. The authorship team for this article was selected from the fields of paediatric exercise science, paediatric medicine, physical education, strength and conditioning and sports medicine

Endothelial-mesenchymal transition occurs during embryonic pulmonary artery development.

Pulmonary vascular remodeling is a process generally associated with pulmonary hypertension that involves intimal thickening, medial hyperthrophy, and plexiform lesions. Morphological studies during pulmonary hypertension have indicated that intimal thickening consists of immature smooth muscle cells (SMCs) associated with determined extracellular matrix components, suggesting an important role for these cells in vascular lesions. Controversy exists regarding the nature and origin of the cells conforming the intimal thickenings. In this study, the authors characterized the in vivo phenotype of the cells located in the pulmonary artery wall during the advanced stages of chicken embryo development and examined whether intimal thickenings are present in such stages. Immunolabeling of cryosections demonstrated presence of intimal thickenings composed of mesenchymal cells that may arise from the endothelium. These cells persist either as nonmuscle throughout the development, or possibly convert to cells expressing alpha -smooth muscle actin (alpha-SM actin). To determine whether pulmonary endothelial cells undergo a transition to mesenchymal cells, the authors used pulmonary artery explants from 10- to 11-day-old chicken embryos and found that explanted endothelial cells detached from the monolayer and acquired mesenchymal characteristics. Some of these cells maintained immunoreactivity for von Willebrand factor (vWF), whereas other jointly lost vWF and gained alpha -SM actin expression (transitional cells), suggesting conversion to SMCs. Therefore, these findings strongly support the authors' in vivo observations and demonstrate that embryonic pulmonary endothelial cells undergo a transition to mesenchymal cells and participate in intimal thickening formation and pulmonary vascular remodeling.

CD40 and CD40L expression in the chicken embryo aorta: possible role in the endothelial-mesenchymal transdifferentiation process.

Endothelial-mesenchymal transdifferentiation (EMT) is believed to play a crucial role in embryonic vascular development and intimal thickening, which contributes to the pathogenesis of atherosclerotic lesions. However, the mechanisms by which it occurs, as well as the signals that control it, have not yet been elucidated. Given the important role played by the CD40-CD40 ligand (CD40L) system during the initiation and progress of atherosclerosis, we investigated whether both CD40 and CD40L were present in the aortic wall during EMT and the advanced stages of chicken embryo development. CD40-CD40L expression was found on endothelial cells (ECs), mesenchymal cells, and smooth muscle cells (SMCs) at all stages examined, and appeared to be distributed across the aortic wall. However, some notable differences between the expression patterns were observed. CD40 had a more restricted distribution compared to CD40L, and did not stain every cell type of the aortic wall. According to immunoblotting and enzyme-linked immunosorbent assay (ELISA) analyses, the CD40L content was highest at day 7 of development. An important and novel finding was the expression of CD40L in areas where ECs transdifferentiate into mesenchymal cells. Specifically, CD40L was associated to the surface of cells that were detaching and migrating from the monolayer of ECs, whereas for CD40 a very diffuse subcellular localization was seen at the monolayer and the detaching and migrating cells. These data suggest a possible role for CD40-CD40L interactions during EMT and the remodeling of the aorta.

El uso inadecuado de los materiales de implante dérmico es la causa más probable de complicación en los pacientes / Inadequate technique in dermal implants is the most probable cause of complications

Los materiales de relleno dérmico son herramientas de dermatólogos o cirujanos plásticos en el manejo de problemas estéticos. Las lesiones que pueden producirse como consecuencia de su uso son inquietantes. Se realiza un estudio descriptivo de las características clínicas e histopatológicas de las lesiones ocasionadas por materiales de relleno dérmico estudiadas en la Sección de Dermatología del Instituto de BIomedicina. Se obtuvieron un total de nueve biopsias procedentes de seis pacientes. Ocho provenían del sitio de implante de material de relleno y una de ellas del lugar donde migró. Cinco pacientes eran de sexo femenino y uno masculino con una edad promedio de 50,8 años. Cinco biopsias provenían del surco nasogeniano. Cinco de los pacientes referían haber recibido implantes con silicona líquida y uno de ellos con una sustancia denominada "cartílago". Siete biopsias presentaban características típicas de infiltración por la forma líquida de silicona. Siete biopsias presentaban vacuolas desde la dermis papilar o media. Se concluye que el material más empleado fue la silicona liquída. Se describen tres patrones histopatológicos en estas lesiones: xantomatoso, en queso suizo e inflamatorio. La causa más probable de la lesión fue inadecuada técnica en más de la mitad de los casos. Se sugiere buscar mecanismos de control para evitar la realización de este procedimiento por personas no autorizadas y sin la adecuada formación