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Abstract Microgravity (µG) experienced during space flights promotes adaptation in several astronauts’ organs and tissues, with skeletal muscles being the most affected. In response to reduced gravitational loading, muscles (especially, lower limb and antigravity muscles) undergo progressive mass loss and alteration in metabolism, myofiber size, and composition. Skeletal muscle precursor cells (MPCs), also known as satellite cells, are responsible for the growth and maintenance of muscle mass in adult life as well as for muscle regeneration following damage and may have a major role in µG-induced muscle wasting. Despite the great relevance for astronaut health, very few data are available about the effects of real µG on human muscles. Based on the MyoGravity project, this study aimed to analyze: (i) the cellular and transcriptional alterations induced by real µG in human MPCs (huMPCs) and (ii) the response of human skeletal muscle to normal gravitational loading after prolonged exposure to µG. We evaluated the transcriptomic changes induced by µG on board the International Space Station (ISS) in differentiating huMPCs isolated from Vastus lateralis muscle biopsies of a pre-flight astronaut and an age- and sex-matched volunteer, in comparison with the same cells cultured on the ground in standard gravity (1×g) conditions. We found that huMPCs differentiated under real µG conditions showed: (i) upregulation of genes related to cell adhesion, plasma membrane components, and ion transport; (ii) strong downregulation of genes related to the muscle contraction machinery and sarcomere organization; and (iii) downregulation of muscle-specific microRNAs (myomiRs). Moreover, we had the unique opportunity to analyze huMPCs and skeletal muscle tissue of the same astronaut before and 30 h after a long-duration space flight on board the ISS. Prolonged exposure to real µG strongly affected the biology and functionality of the astronaut’s satellite cells, which showed a dramatic reduction of responsiveness to activating stimuli and proliferation rate, morphological changes, and almost inability to fuse into myotubes. RNA-Seq analysis of post- vs. pre-flight muscle tissue showed that genes involved in muscle structure and remodeling are promptly activated after landing following a long-duration space mission. Conversely, genes involved in the myelination process or synapse and neuromuscular junction organization appeared downregulated. Although we have investigated only one astronaut, these results point to a prompt readaptation of the skeletal muscle mechanical components to the normal gravitational loading, but the inability to rapidly recover the physiological muscle myelination/innervation pattern after landing from a long-duration space flight. Together with the persistent functional deficit observed in the astronaut’s satellite cells after prolonged exposure to real µG, these results lead us to hypothesize that a condition of inefficient regeneration is likely to occur in the muscles of post-flight astronauts following damage.

Background: Distal pancreatectomy (DP) is a well-established minimally invasive procedure. However, feasibility and technical details when using Versius robotic surgical system are still unexplored. Method: This is a prospective stage 2a development IDEAL (Idea, Development, Exploration, Assessment and Long-term monitoring) case series. All consecutive robotic DP (RDP), including both splenectomy (DPS) and spleen-preserving DP (SPDP), were analysed. Pre- intra- and post-operative details were prospectively recorded. Results: 6 DPS and 3 SPDP were performed between May 2022 and May 2024. Conversion to open was recorded in one case. The average operating time and robot docking time were 185 ​min (range: 118–300) and 9.3 ​min (range: 3–15), respectively. No reoperation or 90-days mortality were recorded. Ports placement, instruments used, and surgical strategy are described in detail. Conclusion: We present the first series on RDP performed by Versius robotic surgical system. The procedure is safe and feasible, and careful patient selection is required for the first cases.

La Microscopía Virtual (MV) es una herramienta tecnológica que utiliza la digitalización de preparados microscópicos para producir imágenes y videos virtuales de alta calidad, emulando un microscopio convencional (MC). El objetivo del presente estudio fue evaluar la capacidad de reconocimiento de estructuras histológicas normales, lesiones histopatológicas básicas, descripciones microscópicas configurando una entidad y el diagnóstico de entidades. Utilizando la MV en 2 cursos de posgrado con modalidad b-learning, utilizando la plataforma Moodle como entorno virtual de aprendizaje (EVA). Se evaluaron los niveles de aprendizaje alcanzados en dos cursos de posgrado de “Patología de la mucosa bucal y Patología de los Maxilares” dictado a 30 Odontólogos generalistas. Se incorporó la MV en vivo y en videos obtenidos a partir de preparados virtuales. Los alumnos recibieron la información clínico-patológica de todos los casos durante el cursado. La evaluación final se realizó sobre dos casos, se observaron y categorizaron los siguientes ítems: A) Reconocimiento de Estructuras Histológicas Normales (EHN). B) Reconocimiento de Lesiones Histopatológicas Básicas (LHB). C) Descripción de Cuadros Microscópicos (DCM) y D) Diagnóstico de Entidades (Dx E). El 80% (n=24) de los participantes fueron capaces de reconocer EHB y 20 % (n=6) con Nivel de 3. En relación a la DCM el 76,6% (n=23) describió correctamente; (n=25) con un Nivel 4. Conclusión: La implementación de la MV mejora el aprendizaje en el reconocimiento de EHN, LHB. DCM y Dx E. La evaluación pormenorizada permite inferir que la habilidad más compleja: Dx E, logró un alto porcentaje de cursantes con el máximo Nivel. Refuerza el concepto de que la enseñanza de menor a mayor complejidad es efectiva. La MV es una herramienta ideal para el proceso de enseñanza aprendizaje de temas de Anatomía Patológica Bucal, como lo ocurrido en nuestra experiencia educativa.

ABSTRACT Objective: To construct a middle-range theory for the nursing diagnosis of Sedentary Lifestyle in young adults. Methods: A methodological study for the validation of a nursing diagnosis based on a Middle-Range Theory, carried out in six stages: definition of the approach; definition of theoretical-conceptual models; definition of main concepts; development of a pictorial scheme; construction of propositions; establishment of causal relationships and evidence for practice. The theory construction was operationalized through an integrative review and supported by Roy’s adaptation model. Results: Three essential attributes were identified; 10 antecedents; 7 clinical consequences; a pictogram, 9 propositions, and 11 causal relationships and evidence for practice. Conclusion: The middle-range theory for the nursing diagnosis of Sedentary Lifestyle in young adults was constructed, expanding the understanding of this phenomenon, to be applied in clinical practice by nurses.

Objetivo. Identificar y analizar los incidentes de productos médicos subestándares, falsificados, no registrados y robados al inicio de la pandemia de COVID-19. Métodos. Búsqueda detallada en los sitios web de las autoridades reguladoras de las Américas. Identificación de los incidentes de medicamentos y dispositivos médicos (incluidos los de diagnóstico in vitro) subestándares falsificados, no registrados y robados. Se determinaron los tipos de productos, las etapas de la cadena de suministro en las que se detectaron y las medidas tomadas por las autoridades. Resultados. Se identificaron 1 273 incidentes en 15 países (1 087 productos subestándares, 44 falsificados, 123 no registrados y 19 robados). La mayor cantidad de incidentes corresponden a dispositivos médicos, desinfectantes y antisépticos. El punto en la cadena de suministro con mayor frecuencia de informes fue la adquisición a través de internet. Las medidas tomadas por las autoridades reguladoras corresponden en su mayoría a: alerta, prohibición de uso, prohibición de publicidad y fabricación, retiro del mercado y seguimiento de eventos adversos. Conclusiones. Se evidenció un número destacable de incidentes de productos médicos subestándares, falsificados, no registrados y robados al inicio de la pandemia por COVID-19. La escasez de insumos, la flexibilización en los requisitos regulatorios y el aumento de la demanda son factores que pueden favorecer el incremento del número de incidentes. Las autoridades reguladoras nacionales de referencia presentaron mayores frecuencias de detección de incidentes y de aplicación de medidas sanitarias. Se observó que se debe abordar el canal de venta por internet con alguna estrategia reguladora para garantizar la distribución segura de productos médicos.

We investigate resonant third-harmonic generation in near-zero index thin films driven out-of-equilibrium by intense optical excitation. Adopting the Landau weak coupling formalism to incorporate electron–electron and electron–phonon scattering processes, we derive a novel set of hydrodynamic equations accounting for collision-driven nonlinear dynamics in sodium. By perturbatively solving hydrodynamic equations, we model third-harmonic generation by a thin sodium film, finding that such a nonlinear process is resonant at the near-zero index resonance of the third-harmonic signal. Thanks to the reduced absorption of sodium, we observe that third-harmonic resonance can be tuned by the impinging pump radiation angle, efficiently modulating the third-harmonic generation process. Furthermore, owing to the metallic sodium response at the pump optical wavelength, we find that the third-harmonic conversion efficiency is maximised at a peculiar thin film thickness where evanescent back-reflection provides increased field intensity within the thin film. Our results are relevant for the development of future ultraviolet light sources, with potential impact for innovative integrated spectroscopy schemes.

We investigate the contribution of inelastic electron collisions to nonlinear (NL) dynamics in ultraviolet plasmonic nanoparticles, exploring their potential for harmonic generation. Employing the Landau weak coupling formalism to model radiation-driven electron dynamics in sodium and aluminum, we account for both electron–electron and electron–phonon scattering processes by a set of hydrodynamic equations, which we solve perturbatively to obtain third-order NL susceptibilities. Furthermore, we model high harmonic generation enhanced by localized surface plasmons in nanospheres composed of such poor metals, demonstrating their efficient operation for extreme ultraviolet generation. Our investigation reveals that plasmonic nanospheres composed of sodium and aluminum produce a large field intensity enhancement of ≃103–105, boosting the harmonic generation process. Our findings indicate that poor metals hold great promise for advanced extreme ultraviolet nano-sources with potential applications in nano-spectroscopy. [ABSTRACT FROM AUTHOR]

Noise manifests ubiquitously in nonlinear spectroscopy, where multiple sources contribute to experimental signals generating interrelated unwanted components, from random point-wise fluctuations to structured baseline signals. Mitigating strategies are usually heuristic, depending on subjective biases such as the setting of parameters in data analysis algorithms and the removal order of the unwanted components. We propose a data-driven frequency-domain denoiser based on a convolutional neural network to extract authentic vibrational features from a nonlinear background in noisy spectroscopic raw data. The different spectral scales in the problem are treated in parallel by means of filters with multiple kernel sizes, which allow the receptive field of the network to adapt to the informative features in the spectra. We test our approach by retrieving asymmetric peaks in stimulated Raman spectroscopy, an ideal test-bed due to its intrinsic complex spectral features combined with a strong background signal. By using a theoretical perturbative toolbox, we efficiently train the network with simulated datasets resembling the statistical properties and lineshapes of the experimental spectra. The developed algorithm is successfully applied to experimental data to obtain noise- and background-free stimulated Raman spectra of organic molecules and prototypical heme proteins.

ABSTRACT Objective: To build a mid-range theory for the nursing diagnosis Overweight in adolescents and young adults. Methods: A methodological study in the light of the theoretical frameworks of Roy and of Lopes, Silva and Herdman. A total of 3,925 articles were retrieved and assessed using the State of the Art Through Systematic Review software. The final sample consisted of 28 articles. Results: The findings converged to 3 essential attributes, 13 antecedents, and 7 consequences. A mid-range theory was built consisting of an illustrated diagram, 11 propositions, and 12 causal relationships. Final considerations: From the creation of the theory, it was possible to better understand the nursing diagnosis Overweight within the context of adolescents and young adults. Understanding nursing phenomena contributes to nursing science’s advancement and strengthening.

Abstract Chemokine receptors constitute an important subfamily of G protein-coupled receptors (GPCRs), and they are critically involved in a broad range of immune response mechanisms. Ligand promiscuity among these receptors makes them an interesting target to explore multiple aspects of biased agonism. Here, we comprehensively characterize two chemokine receptors namely, CXCR4 and CXCR7, in terms of their transducer-coupling and downstream signaling upon their stimulation by a common chemokine agonist, CXCL12, and a small molecule agonist, VUF11207. We observe that CXCR7 lacks G-protein-coupling while maintaining robust βarr recruitment with a major contribution of GRK5/6. On the other hand, CXCR4 displays robust G-protein activation as expected but exhibits significantly reduced βarr-coupling compared to CXCR7. These two receptors induce distinct βarr conformations even when activated by the same agonist, and CXCR7, unlike CXCR4, fails to activate ERK1/2 MAP kinase. We also identify a key contribution of a single phosphorylation site in CXCR7 for βarr recruitment and endosomal localization. Our study provides molecular insights into intrinsic-bias encoded in the CXCR4-CXCR7 system with broad implications for drug discovery.