[Translated article] Mechanical properties variations of immature bone in the earliest stages of development.

INTRODUCTION: Bone as a material varies its composition and mechanical properties throughout life. Although these variations are better understood in adulthood, there is little experimental information on the variation of these properties in early stages of development. The objective of this study is to analyze the mechanical behavior and chemical properties of cortical bone tissue from two animal species in these earliest stages. MATERIAL AND METHODOLOGY: Twenty specimens of cortical bone were manufactured from bovine and ovine species that were in different stages of development (feeding exclusively on breast milk, in the transition period to feed or pasture, and young animals but on a solid food diet). The specimens were subjected to tensile tests, recorded with a high-speed camera to obtain deformation maps. Measurements of the tensile force until the specimen broke were also carried out. A fractographic study was carried out with a scanning electron microscope to analyze the fracture surface and an analysis of the amount of calcium in each of the specimens using X-ray dispersion spectroscopy. RESULTS: A statistically significant and positive correlation was found between the elastic modulus of the specimens and their calcium content. A trend towards more rigid behavior with age was observed. CONCLUSIONS: Young bone tissue tends to stiffen with age as the calcium content increases with an increase in elastic modulus.

Mechanical properties variations of immature bone in the earliest stages of development. / Variación de las propiedades mecánicas del hueso inmaduro en las etapas más tempranas del desarrollo.

INTRODUCTION: Bone as a material varies its composition and mechanical properties throughout life. Although these variations are better understood in adulthood, there is little experimental information on the variation of these properties in early stages of development. The objective of this study is to analyze the mechanical behavior and chemical properties of cortical bone tissue from two animal species in these earliest stages. MATERIAL AND METHODOLOGY: Twenty specimens of cortical bone were manufactured from bovine and ovine species that were in different stages of development (feeding exclusively on breast milk, in the transition period to feed or pasture, and young animals but on a solid food diet). The specimens were subjected to tensile tests, recorded with a high-speed camera to obtain deformation maps. Measurements of the tensile force until the specimen broke were also carried out. A fractographic study was carried out with a scanning electron microscope to analyze the fracture surface and an analysis of the amount of calcium in each of the specimens using X-ray dispersion spectroscopy. RESULTS: A statistically significant and positive correlation was found between the elastic modulus of the specimens and their calcium content. A trend towards more rigid behavior with age was observed. CONCLUSIONS: Young bone tissue tends to stiffen with age as the calcium content increases with an increase in elastic modulus.

Management of Patients with Suspected or Confirmed Antibiotic Allergy: Executive Summary of Guidelines from the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Allergy and Clinical Immunology (SEAIC), the Spanish Society of Hospital Pharmacy (SEFH) and the Spanish Society of Intensive Medicine and Coronary Care Units (SEMICYUC).

Suspected or confirmed antibiotic allergy is a frequent clinical circumstance that influences antimicrobial prescription and often leads to the avoidable use of less efficacious and/or more toxic or costly drugs than first-line antimicrobials. Optimizing antimicrobial therapy in patients with antibiotic allergy labels has become one of the priorities of antimicrobial stewardship programs in several countries. These guidelines aim to make recommendations for the systematic approach to patients with suspected or confirmed antibiotic allergy based on current evidence. An expert panel (11 members of various scientific societies) formulated questions about the management of patients with suspected or confirmed antibiotic allergy. A systematic literature review was performed by a medical librarian. The questions were distributed among panel members who selected the most relevant references, summarized the evidence, and formulated graded recommendations when possible. The answers to all the questions were finally reviewed by all panel members. A systematic approach to patients with suspected or confirmed antibiotic allergy was recommended to improve antibiotic selection and, consequently, clinical outcomes. A clinically oriented, 3-category risk-stratification strategy was recommended for patients with suspected antibiotic allergy. Complementary assessments should consider both clinical risk category and preferred antibiotic agent. Empirical therapy recommendations for the most relevant clinical syndromes in patients with suspected or confirmed ß-lactam allergy were formulated, as were recommendations on the implementation and monitoring of the impact of the guidelines. Antimicrobial stewardship programs and allergists should design and implement activities that facilitate the most appropriate use of antibiotics in these patients.

Management of Patients with Suspected or Confirmed Antibiotic Allergy: Executive Summary of Guidelines from the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC), the Spanish Society of Allergy and Clinical Immunology (SEAIC), the Spanish Society of Hospital Pharmacy (SEFH) and the Spanish Society of Intensive Medicine and Coronary Care Units (SEMICYUC)

Suspected or confirmed antibiotic allergy is a frequent clinical circumstance that influences antimicrobial prescription and often leads to the avoidable use of less efficacious and/or more toxic or costly drugs than first-line antimicrobials. Optimizing antimicrobial therapy in patients with antibiotic allergy labels has become one of the priorities of antimicrobial stewardship programs in several countries. These guidelines aim to make recommendations for the systematic approach to patients with suspected or confirmed antibiotic allergy based on current evidence. An expert panel (11 members of various scientific societies) formulated questions about the management of patients with suspected or confirmed antibiotic allergy. A systematic literature review was performed by a medical librarian. The questions were distributed among panel members who selected the most relevant references, summarized the evidence, and formulated graded recommendations when possible. The answers to all the questions were finally reviewed by all panel members. A systematic approach to patients with suspected or confirmed antibiotic allergy was recommended to improve antibiotic selection and, consequently, clinical outcomes. A clinically oriented, 3-category risk-stratification strategy was recommended for patients with suspected antibiotic allergy. Complementary assessments should consider both clinical risk category and preferred antibiotic agent. Empirical therapy recommendations for the most relevant clinical syndromes in patients with suspected or confirmed ß-lactam allergy were formulated, as were recommendations on the implementation and monitoring of the impact of the guidelines. Antimicrobial stewardship programs and allergists should design and implement activities that facilitate the most appropriate use of antibiotics in these patients (AU)

En la práctica clínica, un antecedente de alergia a los antibióticos, confirmada o sospechada, es frecuente y condiciona la selección de antibióticos, requiriendo con frecuencia el uso de fármacos menos eficaces, más tóxicos o más caros que los antibióticos de primera línea. La optimización del uso de antibióticos en pacientes con este antecedente es una de las prioridades de los programas de optimización de uso de antibióticos (PROA) en varios países. Estas guías pretenden formular recomendaciones para evaluar de una manera sistemática a estos pacientes mediante una aproximación basada en la evidencia. Un panel multidisciplinar constituido por alergólogos, infectólogos, farmacéuticos hospitalarios e intensivistas formularon una serie de preguntas sobre el manejo de estos pacientes; una documentalista realizó la revisión bibliográfica. Las preguntas se distribuyeron entre los miembros del grupo de trabajo, quienes seleccionaron las referencias más relevantes y formularon las correspondientes recomendaciones, que fueron revisadas y aprobadas por todos los miembros del grupo. Es necesaria una aproximación sistemática a los pacientes con antecedentes de alergia a antibióticos para optimizar la selección del tratamiento antibiótico y mejorar los resultados clínicos de estos pacientes cuando precisan antibioterapia. El presente documento recomienda una estrategia de estratificación clínica del riesgo en 3 categorías. La recomendación de realizar evaluaciones complementarias se basa en el riesgo clínico y el antibiótico de primera línea necesario. Además, se formulan recomendaciones de tratamiento antibiótico empírico para los principales síndromes infecciosos en pacientes con alergia confirmada o sospechada. Finalmente, se formulan recomendaciones sobre la implementación y monitorización del impacto de las recomendaciones de la guía (AU)

Tromboembolismo pulmonar durante la pandemia por SARS-CoV-2: características clínicas y radiológicas / Pulmonary embolism during SARS-CoV-2 pandemic: clinical and radiological features

Antecedentes Se ha descrito una elevada incidencia de tromboembolismo pulmonar (TEP) durante la pandemia por coronavirus. Métodos Estudio retrospectivo unicéntrico, con revisión de las angiografías pulmonares por tomografía computarizada solicitadas por sospecha de tromboembolismo pulmonar durante dos períodos, del 01 de marzo del 2020 al 31de mayo del 2020 (pandemia), e igual intervalo en 2019 (control). Resultados Se diagnosticaron 22 tromboembolismos pulmonares durante el período control y 99 en el pandémico, 74 asociados con COVID-19. El 5,3% de los pacientes hospitalizados con COVID-19 sufrió un tromboembolismo pulmonar, con un retraso entre ambos diagnósticos de 9,1 ± 8,4 días. Durante la pandemia, los pacientes con tromboembolismo pulmonar tenían menos condiciones predisponentes (tromboembolismo pulmonar previo 5,1 vs. 18,2%, p = 0,05, cirugía previa 2 vs. 35,4%, p = 0,0001, trombosis venosa profunda 11,1 vs. 45,5%, p = 0,0001), y los tromboembolismos pulmonares periféricos eran más frecuentes (73,5 vs. 50%, p = 0,029). Conclusiones Existe un riesgo incrementado de sufrir un TEP durante la pandemia por SARS-CoV-2, que afecta a pacientes con perfil clínico diferente y causa más frecuentemente TEP distales (AU)

Background A high incidence of pulmonary embolism has been described during the coronavirus pandemic. Methods This work is a single-center retrospective study which reviewed computed tomography pulmonary angiograms ordered due to suspected pulmonary embolism during two periods: from March 1, 2020 to May 31, 2020 (pandemic) and during the same interval in 2019 (control). Results Twenty-two pulmonary embolism were diagnosed during the control period and 99 in the pandemic, 74 of which were associated with COVID-19. Of all patients hospitalized with COVID-19, 5.3% had a pulmonary embolism, with a delay between the two diagnoses of 9.1 ± 8.4 days. During the pandemic, patients with pulmonary embolism had fewer predisposing conditions (previous pulmonary embolism 5.1 vs. 18.2%, p = .05; previous surgery 2 vs. 35.4%, p = .0001; deep vein thrombosis 11.1 vs. 45.5%, p = .0001); peripheral pulmonary embolisms were the most frequent (73.5 vs. 50%, p = . 029). Conclusions There is an increased risk of having a pulmonary embolism during the SARS-CoV-2 pandemic, which affects patients with a different clinical profile and more often causes distal pulmonary embolisms (AU)

Mixed-quantum-classical or fully-quantized dynamics? A unified code to compare methods.

Three methods for non-adiabatic dynamics are compared to highlight their capabilities. Multi-configurational time-dependent Hartree is a full grid-based solution to the time-dependent Schrödinger equation, variational multi-configurational Gaussian (vMCG) uses a less flexible but unrestricted Gaussian wavepacket basis, and trajectory surface hopping (TSH) replaces the nuclear wavepacket with a swarm of classical trajectories. Calculations with all methods using a model Hamiltonian were performed. The vMCG and TSH were also then run in a direct dynamics mode, with the potential energy surfaces calculated on-the-fly using quantum chemistry calculations. All dynamics calculations used the Quantics package, with the TSH calculations using a new interface to a surface hopping code. A novel approach to calculate adiabatic populations from grid-based quantum dynamics using a time-dependent discrete variable representation is presented, allowing a proper comparison of methods. This article is part of the theme issue 'Chemistry without the Born-Oppenheimer approximation'.

Pulmonary embolism during SARS-CoV-2 pandemic: Clinical and radiological features.

BACKGROUND: A high incidence of pulmonary embolism has been described during the coronavirus pandemic. METHODS: This work is a single-center retrospective study which reviewed computed tomography pulmonary angiograms ordered due to suspected pulmonary embolism during two periods: from March 1, 2020 to May 31, 2020 (pandemic) and during the same interval in 2019 (control). RESULTS: Twenty-two pulmonary embolisms were diagnosed during the control period and 99 in the pandemic, 74 of which were associated with COVID-19. Of all patients hospitalized with COVID-19, 5.3% had a pulmonary embolism, with a delay between the two diagnoses of 9.1 ± 8.4 days. During the pandemic, patients with pulmonary embolism had fewer predisposing conditions (previous pulmonary embolism 5.1 vs. 18.2%, p = .05; previous surgery 2 vs. 35.4%, p = .0001; deep vein thrombosis 11.1 vs. 45.5%, p = .0001); peripheral pulmonary embolisms were the most frequent (73.5 vs. 50%, p = . 029). CONCLUSIONS: There is an increased risk of having a pulmonary embolism during the SARS-CoV-2 pandemic, which affects patients with a different clinical profile and more often causes distal pulmonary embolisms.

[Pulmonary embolism during SARS-CoV-2 pandemic: clinical and radiological features]. / Tromboembolismo pulmonar durante la pandemia por SARS-CoV-2: características clínicas y radiológicas.

Background: A high incidence of pulmonary embolism has been described during the coronavirus pandemic. Methods: This work is a single-center retrospective study which reviewed computed tomography pulmonary angiograms ordered due to suspected pulmonary embolism during two periods: from March 1, 2020 to May 31, 2020 (pandemic) and during the same interval in 2019 (control). Results: Twenty-two pulmonary embolism were diagnosed during the control period and 99 in the pandemic, 74 of which were associated with COVID-19. Of all patients hospitalized with COVID-19, 5.3% had a pulmonary embolism, with a delay between the two diagnoses of 9.1 ± 8.4 days. During the pandemic, patients with pulmonary embolism had fewer predisposing conditions (previous pulmonary embolism 5.1 vs. 18.2%, p = .05; previous surgery 2 vs. 35.4%, p = .0001; deep vein thrombosis 11.1 vs. 45.5%, p = .0001); peripheral pulmonary embolisms were the most frequent (73.5 vs. 50%, p = . 029). Conclusions: There is an increased risk of having a pulmonary embolism during the SARS-CoV-2 pandemic, which affects patients with a different clinical profile and more often causes distal pulmonary embolisms.