Impacto de las fracturas por fragilidad en mujeres españolas con osteoporosis posmenopáusica / Impact of fragility fractures in postmenopausal Spanish women with osteoporosis

Objetivo: dada la repercusión que tienen las fracturas por fragilidad y sus secuelas en la vida de las mujeres con osteoporosis posmenopáusica (OPM), el objetivo de este estudio es describir y analizar su impacto en esta población. Material y métodos: se realizó una encuesta a mujeres posmenopáusicas con fractura por fragilidad en un diseño observacional transversal. Se recogieron variables sociodemográficas, impacto de la fractura (necesidad de cuidados, productividad laboral), calidad de vida relacionada con la salud (CVRS, mediante cuestionario QUALEFFO-31) y disposición a pagar (DAP) por recuperarla. Resultados: participaron 120 mujeres, promedio de edad 62 ± 7 años. Las fracturas más frecuentes fueron las de radio distal (29,9 %) y las vertebrales (21,3 %). Un 53,3 % necesitó cuidados durante su recuperación (76,5 % informales; 24,9 % formales) y un 4,2 % tuvo que ingresar en un centro/residencia sociosanitaria. De aquellas que trabajaban cuando se produjo la fractura (62,5 %), el 56 % vio su vida laboral afectada (69,3 % incapacidad temporal; 17,3 % incapacidad permanente; 10,7 % reducción de jornada; 10,7 % abandono laboral; 5,3 % permiso/excedencia; 3,6 % prejubilación). El impacto de la fractura se debió principalmente al dolor (71,7 %), dificultad para realizar actividades cotidianas (48,3 %), problemas de movilidad (46,7 %) y estado emocional (41,7 %). La mayor DAP se ofreció por recuperar la capacidad para realizar actividades cotidianas y el estado emocional. La puntuación total QUALEFFO-31 (0-100) fue 49,9 ± 10,8 (función mental: 68,3 ± 7,3; dolor: 56 ± 22,6; función física: 39,3 ± 15,5). Conclusiones: las fracturas por fragilidad tienen un alto impacto en la calidad de vida de las mujeres con OPM. Resulta fundamental poner en valor aquellos aspectos que más les preocupan para optimizar su abordaje. (AU)

Objective: Given the impact of fragility fractures and their consequences on the lives of women with postmenopausal osteoporosis (PMO), the objective of this study is to describe and analyze the impact of this kind of fractures on this population. Materials and methods: A survey was conducted among postmenopausal women with fragility fractures in a cross-sectional observational design. Sociodemographic variables, fracture impact (need for care, work productivity), and data on health-related quality of life (HRQoL, assessed using the QUALEFFO-31 questionnaire), and willingness to pay (WTP) to regain HRQoL were collected. Results: A total of 120 women participated, with a mean age of 62 ± 7 years. The most frequent fractures described were distal radius fractures (29.9 %), followed by vertebral fractures (21.3 %). A total of 53.3 % required care during their recovery (76.5 %, informal; 24.9 %, formal), and 4.2 % had to be admitted to a health care or nursing home. Among those who were working when the fracture occurred (62.5 %), 56 % had their working life affected (69.3 %, temporary disability; 17.3 %, permanent disability; 10.7 %, reduced working hours; 10.7 %, quit their jobs; 5.3 %, leave of absence; and 3.6 %, early retirement). The impact of the fracture was primarily due to pain (71.7 %), difficulty performing activities of daily living (48.3 %), mobility problems (46.7 %), and emotional state (41.7 %). The highest WTP was offered to regain the ability to perform activities of daily living and improve the emotional state. The overall QUALEFFO-31 score (0-100) was 49.9 ± 10.8 (mental function, 68.3 ± 7.3; pain, 56 ± 22.6; physical function, 39.3 ± 15.5). Conclusions: Fragility fractures play a significant role on the quality of life of women with PMO. It is of paramount importance to value the aspects that concern them the most to optimize their management. (AU)

Seroepidemiology Study of Porcine Epidemic Diarrhea Virus in Mexico by Indirect Enzyme-Linked Immunosorbent Assay Based on a Recombinant Fragment of N-Terminus Domain Spike Protein.

Porcine epidemic diarrhea (PED) is an intestinal disease caused by the porcine epidemic diarrhea virus (PEDV) and affects Mexico's swine industry. Despite the disease initially being described in Mexico in 2013, there has been no research into the virus's seroepidemiology carried out in Mexico. Thus, the goal of this study was to develop an indirect ELISA (iELISA) based on a recombinant N-terminal domain truncated spike (S) protein (rNTD-S) of PEDV to evaluate serum obtained from different pig-producing states in Mexico. A total of 1054 sera were collected from pig farms, slaughterhouses, and backyard production in the states of Aguascalientes, Guanajuato, Hidalgo, Jalisco, Morelos, Queretaro, Sinaloa, and Veracruz between 2019 and 2021. The rNTD-S protein was expressed in E. coli BL21 (DE3) cells. Negative and positive serum samples used in the iELISA were previously tested by Western blot. According to our findings, 61.66% of the serum samples (650/1054) were positive, with Jalisco having the highest percentage of positive samples, at a rate of 21.44% (226/1054). This is the first seroepidemiology study of PEDV carried out in Mexico, revealing that the virus is still circulating since the initial outbreak; furthermore, it provides an overview of PEDV's spread and high level of persistence across the country's key swine-producing states.

A Candidate Antigen of the Recombinant Membrane Protein Derived from the Porcine Deltacoronavirus Synthetic Gene to Detect Seropositive Pigs.

Porcine deltacoronavirus (PDCoV) is an emergent swine coronavirus which infects cells from the small intestine and induces watery diarrhea, vomiting and dehydration, causing mortality in piglets (>40%). The aim of this study was to evaluate the antigenicity and immunogenicity of the recombinant membrane protein (M) of PDCoV (rM-PDCoV), which was developed from a synthetic gene obtained after an in silico analysis with a group of 138 GenBank sequences. A 3D model and phylogenetic analysis confirmed the highly conserved M protein structure. Therefore, the synthetic gene was successfully cloned in a pETSUMO vector and transformed in E. coli BL21 (DE3). The rM-PDCoV was confirmed by SDS-PAGE and Western blot with ~37.7 kDa. The rM-PDCoV immunogenicity was evaluated in immunized (BLAB/c) mice and iELISA. The data showed increased antibodies from 7 days until 28 days (p < 0.001). The rM-PDCoV antigenicity was analyzed using pig sera samples from three states located in "El Bajío" Mexico and positive sera were determined. Our results show that PDCoV has continued circulating on pig farms in Mexico since the first report in 2019; therefore, the impact of PDCoV on the swine industry could be higher than reported in other studies.

[Corticoid treatment and SARS-CoV-2 variants: two independent factors associated with COVID-19 mortality in a Spanish regional hospital].

BACKGROUND: Pandemic inter-wave hospital admissions and COVID-19-related mortality rates vary greatly. Some of the factors that may be playing part in this are the profile of the patients, viral variants, pharmacological treatments, or preventive measures. This work aimed to analyze the factors associated with mortality in COVID-19 patients admitted to hospital during 2020-2021. METHODS: Retrospective cohort study with COVID-19 patients admitted to Hospital de Barbastro (Spain) during 2020-2021. Data were collected from the Spanish Conjunto Mínimo Básico de Datos and microbiology and electronic prescription records. RESULTS: During the study period, 908 patients were consecutively admitted for COVID-19 (median age 70 years, 57.2% males); 162 (17.8%) patients died. We identified seven successive epidemiological waves. The following variables significantly associated to higher mortality: age, arterial hypertension, chronic renal failure, dementia, chronic obstructive pulmonary disease, heart failure, prior stroke, Charlson index, and wave 2; wave 4 was associated to greater survival. The multivariate analysis showed that age (OR=1.11; 95% CI: 1.09-1.14), chronic obstructive pulmonary disease (OR=2.33; 95% CI: 1.18-4.57), wave 2 (OR=2.57; 95% CI: 1.10-6.00), and wave 3 (OR=2.94; 95% CI: 1.17-7.38) associated with higher mortality. Glucocorticoid treatment was the only protective factor (OR=0.29; 95%CI: 0.14-0.62). CONCLUSIONS: This study confirms the therapeutic utility of glucocorticoids to reduce in-hospital mortality due to COVID-19. Heterogeneous mortality rates between the different COVID-19 waves suggest a direct role of viral variants as determinants of lethality, regardless of the patient's history.

Tratamiento corticoide y variantes SARS-CoV-2: dos factores independientes de mortalidad por COVID-19 en un hospital comarcal / Corticoid treatment and SARS-CoV-2 variants: two independent factors associated with COVID-19 mortality in a Spanish regional hospital

Fundamento: Existe gran heterogeneidad en tasas de ingresohospitalario y mortalidad derivada entre olas de COVID-19, pudiendo deberse al perfil de paciente, las variantes virológicas, lostratamientos y las medidas preventivas. El objetivo de este trabajoes analizar los factores asociados a mortalidad de pacientes ingresados por infección COVID-19 hasta finales de 2021.Métodología: Estudio de cohortes retrospectivo de pacientes COVID-19 en el Hospital General de Barbastro durante 2020 y 2021.Los datos se obtuvieron del Conjunto Mínimo Básico de Datos(CMBD), de registros de Microbiología y de prescripción electrónica de fármacos.Resultados: En el periodo de estudio ingresaron consecutivamente 908 pacientes por COVID-19 (mediana de 70 años, 57,2%varones), de los que 162 fallecieron (17,8%). Identificamos sieteolas epidemiológicas sucesivas. Las variables significativamenteasociadas a una mayor mortalidad fueron: edad, antecedentesde hipertensión arterial, insuficiencia renal crónica, demencia,EPOC, insuficiencia cardiaca, ictus previo, puntuación Charlsony la ola 2; la ola 4 se asoció a mayor supervivencia. En el análisismultivariante las variables asociadas a mayor mortalidad fueron:edad (OR=1,11; IC95%: 1,09-1,14), EPOC (OR=2,33; IC95%: 1,18-4,57), y las olas 2 (OR=2,57; IC95%: 1,10-6,00) y 3 (OR=2,94; IC95%:1,17-7,38); el tratamiento con glucocorticoides actuó como factorprotector (OR=0,29; IC95%: 0,14-0,62).Conclusiones: Este estudio confirma la utilidad terapéutica de losglucocorticoides para disminuir la mortalidad hospitalaria porCOVID-19. La diferente mortalidad entre las distintas olas epidemiológicas sugiere un papel directo de las variantes virológicascomo determinantes de la letalidad, independientemente de losantecedentes del paciente.(AU)

Background: Pandemic inter-wave hospital admissions andCOVID-19-related mortality rates vary greatly. Some of thefactors that may be playing part in this are the profile of thepatients, viral variants, pharmacological treatments, or preventive measures. This work aimed to analyze the factors associated with mortality in COVID-19 patients admitted to hospitalduring 2020-2021.Methods: Retrospective cohort study with COVID-19 patientsadmitted to Hospital de Barbastro (Spain) during 2020-2021. Datawere collected from the Spanish Conjunto Mínimo Básico de Datos and microbiology and electronic prescription records.Results: During the study period, 908 patients were consecutively admitted for COVID-19 (median age 70 years, 57.2%males); 162 (17.8%) patients died. We identified seven successive epidemiological waves. The following variables significantly associated to higher mortality: age, arterial hypertension,chronic renal failure, dementia, chronic obstructive pulmonarydisease, heart failure, prior stroke, Charlson index, and wave2; wave 4 was associated to greater survival. The multivariateanalysis showed that age (OR=1.11; 95% CI: 1.09-1.14), chronic obstructive pulmonary disease (OR=2.33; 95% CI: 1.18-4.57),wave 2 (OR=2.57; 95% CI: 1.10-6.00), and wave 3 (OR=2.94; 95%CI: 1.17-7.38) associated with higher mortality. Glucocorticoidtreatment was the only protective factor (OR=0.29; 95%CI: 0.14-0.62).Conclusions: This study confirms the therapeutic utility of glucocorticoids to reduce in-hospital mortality due to COVID-19.Heterogeneous mortality rates between the different COVID-19waves suggest a direct role of viral variants as determinants oflethality, regardless of the patient’s history.(AU)

Circulating Osteogenic Progenitor Cells Enhanced with Teriparatide or Denosumab Treatment.

Circulating osteogenic precursor (COP) cells are peripheral blood cells with a capacity for osteogenesis. The objective of our study was to ascertain the percentage of COPs as an early biomarker of osteoporosis and the effect of these cells in response to Denosumab (DmAb) (anti-resorptive) or to Teriparatide (TPDP) (anabolic) as very effective drugs in the treatment of the illness. A first study was conducted on healthy volunteers, with three age ranges, to determine the percentage of COPs and relate it to their anthropometric and biochemical characteristics, followed by a second longitudinal study on patients with osteoporosis, whereby one group of patients was treated with TPTD and another with DmAb. All were analyzed by cytometry for COP percentage in blood, bone turnover markers, and bone mass. Our findings show that COPs are influenced by age and become more prolific in the stages of growth and skeletal maturation. A higher percentage of COPs is found in osteoporotic disease, which could constitute a predictive marker thereof. We also show how treatment with TPTD or DmAb mobilizes circulating osteogenic precursors in the blood. Significant increases in % COPs were observed after 12 months of treatment with Dmb (21.9%) and TPTD (17%). These results can be related to an increase in osteogenesis and, consequently, a better and more efficient repair of bone tissue.

Two-methods approach to follow up biomass by impedance spectroscopy: Bacillus thuringiensis fermentations as a study model.

Impedance spectroscopy is used for the characterization of electrochemical systems as well as for the monitoring of bioprocesses. However, the data obtained using this technique allow multiple interpretations, depending on the methodology implemented. Hence, it is necessary to establish a robust methodology to reliably follow-up biomass in fermentations. In the present work, two methodological approaches, mainly used for the characterization of electrochemical systems, were employed to characterize and determine a frequency that allows the monitoring of biomass in Bacillus thuringiensis fermentations by impedance spectroscopy. The first approach, based on a conventional analysis, revealed a single distribution with a characteristic frequency of around 2 kHz. In contrast, the second approach, based on the distribution of relaxation times, gave three distributions (A, B, and C). The C distribution, found near 9 kHz, was more related to the microbial biomass than the distribution at 2 kHz using the equivalent circuits. The time course of the B. thuringiensis fermentation was followed; bacilli, spores, glucose, and acid and base consumption for pH were determined out of line; and capacitance at 9 kHz was monitored. The correlation between the time course data and the capacitance profile indicated that the monitoring of B. thuringiensis at 9 kHz mainly corresponds to extracellular activity and, in a second instance, to the cellular concentration. These results show that it is necessary to establish a robust and reliable methodology to monitor fermentation processes by impedance spectroscopy, and the distribution of relaxation times was more appropriate. KEY POINTS: • Application of impedance spectroscopy for bioprocess monitoring • Low-frequency monitoring of biomass in fermentations • Analysis of impedance data by two methodological approaches.

On-line monitoring of industrial interest Bacillus fermentations, using impedance spectroscopy.

Impedance spectroscopy is a technique used to characterize electrochemical systems, increasing its applicability as well to monitor cell cultures. During their growth, Bacillus species have different phases which involve the production and consumption of different metabolites, culminating in the cell differentiation process that allows the generation of bacterial spores. In order to use impedance spectroscopy as a tool to monitor industrial interest Bacillus cultures, we conducted batch fermentations of Bacillus species such as B. subtilis, B. amyloliquefaciens, and B. licheniformis coupled with this technique. Each fermentation was characterized by the scanning of 50 frequencies between 0.5 and 5 MHz every 30 min. Pearson's correlation between impedance and phase angle profiles (obtained from each frequency scanned) with the kinetic profiles of each strain allowed the selection of fixed frequencies of 0.5, 1.143, and 1.878 MHz to follow-up of the fermentations of B. subtilis, B. amyloliquefaciens and B. licheniformis, respectively. Dielectric profiles of impedance, phase angle, reactance, and resistance obtained at the fixed frequency showed consistent changes with exponential, transition, and spore release phases.

The Fracture Liaison Service of the Virgen Macarena University Hospital Reduces the Gap in the Management of Osteoporosis, Particularly in Men. It Meets the International Osteoporosis Foundation Quality Standards.

OBJECTIVES: To describe the Fracture Liaison Service (FLS), to know the characteristics of the patients attended with emphasis on sex differences, and to know the compliance of International Osteoporosis Foundation (IOF) quality standards. METHODS: Observational, prospective research. All the consecutive patients that attended in usual clinical practice from May 2018 to October 2019, were over 50 years, and with a fragility fracture (FF), were included. RESULTS: Our FLS is a type A multidisciplinary unit. We included 410 patients, 80% women. FF recorded in 328 women were: Hip (132, 40%), Clinical Vertebral (81, 25%) and No hip No vertebral (115, 35%). Those in 82 men were: Hip (53, 66%), Clinical Vertebral (20, 24%) and No hip No vertebral (9, 10%), p = 0.0001. Men had more secondary osteoporosis (OP). The most remarkable result was the low percentage of patients with OP receiving treatment and the differences between sex. Forty-nine (16%) women versus nine (7%) men had received it at some point in their lives, p = 0.04. The probability of a man not receiving prior treatment was 2.5 (95%CI 1.01-6.51); p = 0.04, and after the FF was 0.64 (0.38-1.09). Treatment adherence in the first year after the FLS was 96% in both sexes. The completion of IOF quality standards was bad for patient identification and reference time. It was poor for initial OP screening standard and good for the remaining ten indicators. CONCLUSIONS: the FLS narrowed the gap in diagnosis, treatment, and follow-up of fragility fracture patients, especially men. The FLS meets the IOF quality standards.

Fragility Fractures and Imminent Fracture Risk in the Spanish Population: A Retrospective Observational Cohort Study.

Fragility fractures constitute a major public health problem worldwide, causing important high morbidity and mortality rates. The aim was to present the epidemiology of fragility fractures and to assess the imminent risk of a subsequent fracture and mortality. This is a retrospective population-based cohort study (n = 1369) with a fragility fracture. We estimated the incidence rate of index fragility fractures and obtained information on the subsequent fractures and death during a follow-up of up to three years. We assessed the effect of age, sex, and skeletal site of index fracture as independent risk factors of further fractures and mortality. Incidence rate of index fragility fractures was 86.9/10,000 person-years, with highest rates for hip fractures in women aged ≥80 years. The risk of fracture was higher in subjects with a recent fracture (Relative Risk(RR), 1.80; p < 0.01). Higher age was an independent risk factor for further fracture events. Significant excess mortality was found in subjects aged ≥80 years and with a previous hip fracture (hazard ratio, 3.43 and 2.48, respectively). It is the first study in Spain to evaluate the incidence of major osteoporotic fractures, not only of the hip, and the rate of imminent fracture. Our results provide further evidence highlighting the need for early treatment.

Do Different Models Induce Changes in Mortality Indicators? That Is a Key Question for Extending the Lee-Carter Model.

The parametric model introduced by Lee and Carter in 1992 for modeling mortality rates in the USA was a seminal development in forecasting life expectancies and has been widely used since then. Different extensions of this model, using different hypotheses about the data, constraints on the parameters, and appropriate methods have led to improvements in the model's fit to historical data and the model's forecasting of the future. This paper's main objective is to evaluate if differences between models are reflected in different mortality indicators' forecasts. To this end, nine sets of indicator predictions were generated by crossing three models and three block-bootstrap samples with each of size fifty. Later the predicted mortality indicators were compared using functional ANOVA. Models and block bootstrap procedures are applied to Spanish mortality data. Results show model, block-bootstrap, and interaction effects for all mortality indicators. Although it was not our main objective, it is essential to point out that the sample effect should not be present since they must be realizations of the same population, and therefore the procedure should lead to samples that do not influence the results. Regarding significant model effect, it follows that, although the addition of terms improves the adjustment of probabilities and translates into an effect on mortality indicators, the model's predictions must be checked in terms of their probabilities and the mortality indicators of interest.

Yodo tópico y glándula tiroidea. ¿Se debe tomar alguna precaución? / Topical iodine and thyroid gland. Do we have to take some caution?

No disponible

Influence of Free Volume Determined by Positron Annihilation Lifetime Spectroscopy (PALS) on Gas Permeability of Cellulose Nanocrystal Films.

Cellulose nanocrystals (CNCs) are of increasing interest for packaging applications because of their biodegradability, low cost, high crystallinity, and high aspect ratio. The objective of this study was to use positron annihilation lifetime spectroscopy (PALS) to investigate the free volume of CNC films with different structural arrangements (chiral nematic vs shear-oriented CNC films) and relate this information to gas barrier performance. It was found that sheared CNC films with higher CNC alignment have lower free volume and hence have more tortuosity than chiral nematic self-assembled films, which lowers gas diffusion throughout the films. The overall barrier performance of the aligned CNC film obtained in this study has a higher barrier performance than high barrier polymer films like PVOH and EVOH. Furthermore, a modified model was developed for single-component CNC films to predict the gas permeability with variation of CNC alignment with validation by the data taken.

Utilidad de los modelos predictivos de embolia pulmonar / Usefulness of predictive models of pulmonary embolism

ANTECEDENTES: Ante la sospecha de embolia pulmonar (EP), las guías recomiendan el empleo de escalas de probabilidad clínica, medición del dímero D y, en determinados casos, confirmar mediante angiografía pulmonar mediante tomografía computarizada (APTC) o gammagrafía. Recientemente se ha planteado ajustar el dímero D según edad o usar escalas más sencillas (algoritmo YEARS) para una mejor selección de los pacientes. OBJETIVO: Definir el grado de aplicación de las guías en nuestra población y comparar sensibilidad, especificidad y valores predictivos positivo y negativo de los diferentes modelos diagnósticos: modelo estándar (Wells 2 categorías+dímero D), modelo ajustado por edad (Wells 2 categorías+dímero D ajustado por edad), algoritmo YEARS. MATERIAL Y MÉTODOS: Estudio retrospectivo de todos los pacientes que se sometieron en nuestro centro a APTC para diagnóstico de EP durante un año. RESULTADOS: De 618 casos (el 85,4% de las APTC) iniciales se incluyeron 544 pacientes. Se diagnosticaron 113 EP (20,8%). El grado de aplicación del modelo estándar fue muy alto (90,1%) y demostró presentar la mejor relación sensibilidad y valor predictivo negativo (sensibilidad=1, valor predictivo negativo=1). Los nuevos modelos podrían reducir el número de exploraciones (17; 3,2% modelo ajustado por edad y 48; 8,8% modelo YEARS) con riesgo de falsos negativos (2 EP [1,8%] no diagnosticadas respectivamente). CONCLUSIONES: Los modelos diagnósticos actuales para EP llevan a la realización de un gran número de exploraciones innecesarias. Los nuevos modelos podrían reducir el número de APTC aunque con un mínimo riesgo de falsos negativos

BACKGROUND: Faced with the suspicion of pulmonary embolism (PE), the guidelines recommend the use of clinical probability scales, measurement of D-dimer and, in certain cases, confirmation by pulmonary angiography by computed tomography (CTPA) or scintigraphy. Recently, it has been proposed to adjust the D-dimer according to age or use simpler scales (YEARS algorithm) for a better selection of patients. OBJECTIVE: To define the degree of application of the guidelines in our population and compare sensitivity, specificity and positive and negative predictive values of the different diagnostic models: Standard model (Wells 2 categories+D-dimer), Model adjusted for age (Wells 2 categories+D-dimer adjusted for age), YEARS algorithm. MATERIAL AND METHODS: A retrospective study of all patients who underwent APTC at our centre for the diagnosis of PE over one year. RESULTS: Of 618 cases (85.4% of initial APTC), 544 patients were included. A total of 113 EPs were diagnosed (20.8%). The degree of application of the standard model was very high (90.1%) and proved to have the best sensitivity and negative predictive value ratio (sensitivity=1.0, negative predictive value=1.0). The new models could reduce the number of scans (17, 3.2% model adjusted for age and 48, 8.8% model YEARS) with a risk of false negatives (2 PE [1.8%] undiagnosed respectively). CONCLUSIONS: The current diagnostic models for PE lead to a large number of unnecessary explorations. The new models could reduce the number of APTC although with a minimum risk of false negatives

Usefulness of predictive models of pulmonary embolism. / Utilidad de los modelos predictivos de embolia pulmonar.

BACKGROUND: Faced with the suspicion of pulmonary embolism (PE), the guidelines recommend the use of clinical probability scales, measurement of D-dimer and, in certain cases, confirmation by pulmonary angiography by computed tomography (CTPA) or scintigraphy. Recently, it has been proposed to adjust the D-dimer according to age or use simpler scales (YEARS algorithm) for a better selection of patients. OBJECTIVE: To define the degree of application of the guidelines in our population and compare sensitivity, specificity and positive and negative predictive values of the different diagnostic models: Standard model (Wells 2 categories+D-dimer), Model adjusted for age (Wells 2 categories+D-dimer adjusted for age), YEARS algorithm. MATERIAL AND METHODS: A retrospective study of all patients who underwent APTC at our centre for the diagnosis of PE over one year. RESULTS: Of 618 cases (85.4% of initial APTC), 544 patients were included. A total of 113 EPs were diagnosed (20.8%). The degree of application of the standard model was very high (90.1%) and proved to have the best sensitivity and negative predictive value ratio (sensitivity=1.0, negative predictive value=1.0). The new models could reduce the number of scans (17, 3.2% model adjusted for age and 48, 8.8% model YEARS) with a risk of false negatives (2 PE [1.8%] undiagnosed respectively). CONCLUSIONS: The current diagnostic models for PE lead to a large number of unnecessary explorations. The new models could reduce the number of APTC although with a minimum risk of false negatives.

Estimating the occurrence of traffic accidents near school locations: A case study from Valencia (Spain) including several approaches.

Traffic safety around school locations is a topic of particular interest given the large number of vulnerable users, such as pedestrians or cyclists, that commute to them at certain times of the day. A dataset of traffic accidents recorded in Valencia (Spain) during 2014 and 2015 is analyzed in order to estimate the effects that school locations produce on traffic risk within their surroundings. The four typologies of school in this city according to the academic levels they offer (All-level, Preschool, Primary, Secondary) are distinguished and taken into consideration for the analysis. Two time windows comprising the starting time in the morning and the evening time once day school has ended are analyzed independently. Several statistical methods are used, including observed vs expected ratios, macroscopic conditional autoregressive modelling, logistic regression in the context of a case-control study design and risk modelling in relation to several school locations. The distances to each type of school and a set of environmental, traffic-related, demographic and socioeconomic covariates are employed for the analysis. The macroscopic modelling of accident counts and the modelling of risk as a function of the distance to each type of school serves to confirm that proximity to a school has an effect on the incidence of traffic accidents in particular time windows. Specifically, school types coexisting in Valencia show differential behaviour in this regard. In addition, several covariates have displayed a positive (bus stop density, complex intersections, main road length) and negative (land use entropy) association with accident counts in the time windows investigated. Finally, the definition of a case-control study design enabled us to observe some differences undetected by the macroscopic approaches that would require further research.

Identification of differential risk hotspots for collision and vehicle type in a directed linear network.

Traffic accidents can take place in very different ways and involve a substantially distinct number and types of vehicles. Thus, it is of interest to know which parts of a road structure present an overrepresentation of a specific type of traffic accident, specially for some typologies of collisions and vehicles that tend to trigger more severe consequences for the users being involved. In this study, a spatial approach is followed to estimate the risk that different types of collisions and vehicles present in the central area of Valencia (Spain), considering the accidents observed in this city during the period 2014-2017. A directed spatial linear network representing the non-pedestrian road structure of the area of interest was employed to guarantee an accurate analysis of the point pattern. A kernel density estimation technique was used to approximate the probability of risk along the network for each collision and vehicle type. A procedure based on these estimates and the sample size locally available within the network was designed and tested to determine a set of differential risk hotspots for each typology of accident considered. A Monte Carlo based simulation process was then defined to assess the statistical significance of each of the differential risk hotspots found, allowing the elaboration of rankings of importance and the possible rejection of the least significant ones.

Investigation of the consequences of the modifiable areal unit problem in macroscopic traffic safety analysis: A case study accounting for scale and zoning.

Traffic safety analysis at the macroscopic level usually relies on previously defined areal traffic analysis zones (TAZs) that are used as the units of investigation. Hence, statistical inference is made on the basis of such units, implying that the consideration of a certain TAZ configuration may influence the results and conclusions achieved. Regarding this, the modifiable areal unit problem (MAUP) is a well-known issue in the field of spatial statistics, which refers to the effects that arise in statistical properties and estimations when there is a change in areal units of analysis. In this paper, the consequences of MAUP have been investigated through a dataset of traffic crashes that occurred in Valencia within the years 2014 and 2015 and two common statistical models: a conditional autoregressive model and a geographically weighted regression. In the absence of an established TAZ scheme for the city, four classes of basic spatial units (BSUs) were considered: census tracts, hexagonal units and two types with construction based on the structure of main roads and intersections of the city. Each of these BSU types was specified at different levels of spatial aggregation. The main research objective was to investigate the final effects that changes in BSU type and scale have on model parameter estimations, but also the specific alterations that MAUP causes to data in terms of the distributional characteristics of the response, multicollinearity among the covariates and covariates' spatial autocorrelation. The results showed the presence and severity of MAUP for the dataset and area that were analysed. Although effects from scale variations were more moderate, changing the BSU type affected the results severely. The joint use of hexagonal units and a conditional autoregressive model achieved the best performance among all the possibilities explored, but the choice of a proper BSU unit should rely on more factors. Despite MAUP effects, educational centres showed a consistent (and negative) association with traffic crashes, a fact possibly related to their distribution across the whole city. Other covariates revealed a positive correlation with crash counts, but these findings were more uncertain given the discrepancies found at different scales and zonings.