Incidence, treatment, and factors associated with survival of out-of-hospital cardiac arrest attended by Spanish emergency services: report from the Out-of-Hospital Spanish Cardiac Arrest Registry for 2022. / Incidencia, tratamiento y factores asociados con la supervivencia de la parada cardiaca extrahospitalaria atendida por los servicios de emergencias en España: informe 2022 del registro OHSCAR.

SUMMARY: Out-of-hospital cardiac arrest is a serious public health problem worldwide. The annual incidence is estimated at around 400 000 cases in Europe and the United States, and survival rates scarcely reach 10%. However, there is considerable variation between countries and even between regions that share a similar health care system within a single country. Information recorded by the Out-of-Hospital Spanish Cardiac Arrest Registry (OHSCAR) provides information on care provided by emergency ambulance services, final health outcomes after cardiac arrest cases (including variations), the possibility of organ donation, and the impact of the COVID-19 pandemic. This paper presents the OHSCAR report for Spanish emergency services for the year 2022.

RESUMEN: La parada cardiorrespiratoria extrahospitalaria (PCREH) es un grave problema de salud pública mundial, con una incidencia anual estimada entorno a entorno a los 350.000 y 400.000 casos de PCERH en Europa y Estados Unidos, respectivamente. La supervivencia final se sitúa en porcentajes que apenas alcanzan el 10%, aunque existe una importante variabilidad entre países e incluso entre regiones del mismo país con modelos de atención similares. En España, el Registro Español de Parada Cardiaca Extrahospitalaria (acrónimo OHSCAR) ha ofrecido información sobre la asistencia a la PCRE prestada por los servicios de emergencias (SEM) y sus resultados finales en salud, así como sobre variabilidad, posibilidades de programas de donación o impacto de la pandemia COVID-19. A continuación se presenta el informe OHSCAR correspondiente a la asistencia a la PCRE por los SEM españoles durante el año 2022.

Ongoing CPR with an onboard physician.

Introduction: Recent data are not available on ongoing CPR for emergency services with an onboard physician. The aim of the present study was to identify factors associated with the decision to transport patients to hospital with ongoing CPR and examine their survival to hospital discharge with good neurological status. Methods: An observational study based on a registry of out-of-hospital cardiac arrests attended to by emergency services with an onboard physician. All OHCA cases occurring between the 1st of January and the 31st of December 2022 were included. Patients receiving ongoing CPR during transport to the hospital were compared with patients pronounced dead at the scene following arrival of the care team. The dependent variable was ongoing CPR during transport to the hospital. The main characteristics and the neurological status of patients surviving to discharge were described. Results: A total of 9321 cases were included, of which 350 (3.7%) were transported to hospital with ongoing CPR. Such patients were young (59.9 ± 20.1 years vs 64.6 ± 16.9 years; p < 0.001; 95%CI: 0.98 [0.98; 0.99]) with arrest taking place outside of the home (151 [44.5%] vs 4045 [68.01%]; p < 0.001; 95%CI: 0.41 [0.31; 0.54]) and being witnessed by EMS (126 [36.0%] vs 667 [11.0%]; p < 0.001; 95%CI: 4.31 [3.19; 5.80]), whilst initial rhythm differed from asystole (164 [47.6%] vs 4325 [73.0%]; p < 0.01; 95%CI: 0.44 [0.33; 0.60]) and a mechanical device was more often employed during resuscitation and transport to hospital (199 [56.9%] vs 2050 [33.8%]; p < 0.001; 95%CI: 2.75 [2.10; 3.59]). Seven patients (2%) were discharged alive from hospital, five with ad integrum neurological recovery (CPC1) and two with minimally impaired neurological function (CPC2). Conclusions: The strategy of ongoing CPR is uncommon in EMS with an onboard physician. Despite their limited efficacy, the availability of mechanical chest compression devices, together with the possibility of specific hospital treatments, mainly ICP and ECMO, opens up the possibility of this approach with determined patients.

Study of risk factors for injuries due to cardiopulmonary resuscitation with special focus on the role of the heart: A machine learning analysis of a prospective registry with multiple sources of information (ReCaPTa Study).

Background: The study of thoracic injuries and biomechanics during CPR requires detailed studies that are very scarce. The role of the heart in CPR biomechanics has not been determined. This study aimed to determine the risk factors importance for serious ribcage damage due to CPR. Methods: Data were collected from a prospective registry of out-of-hospital cardiac arrest between April 2014 and April 2017. This study included consecutive out-of-hospital CPR attempts undergoing an autopsy study focused on CPR injuries. Cardiac mass ratio was defined as the ratio of real to expected heart mass. Pearson's correlation coefficient was used to select clinically relevant variables and subsequently classification tree models were built. The Gini index was used to determine the importance of the associated serious ribcage damage factors. The LUCAS® chest compressions device forces and the cardiac mass were analyzed by linear regression. Results: Two hundred CPR attempts were included (133 manual CPR and 67 mechanical CPR). The mean age of the sample was 60.4 ± 13.5, and 56 (28%) were women. In all, 65.0% of the patients presented serious ribcage damage. From the classification tree build with the clinically relevant variables, age (0.44), cardiac mass ratio (0.26), CPR time (0.22), and mechanical CPR (0.07), in that order, were the most influential factors on serious ribcage damage. The chest compression forces were greater in subjects with higher cardiac mass. Conclusions: The heart plays a key role in CPR biomechanics being cardiac mass ratio the second most important risk factor for CPR injuries.

The S-REAL study: Spanish real-world data on unresectable stage III NSCLC patients treated with durvalumab after chemoradiotherapy.

OBJECTIVES: The S-REAL study aimed to assess the effectiveness of durvalumab as consolidation therapy after definitive chemoradiotherapy (CRT) in a real-world cohort of patients with locally advanced, unresectable stage III non-small cell lung cancer (LA-NSCLC) included in a Spanish early access program (EAP). METHODS: In this multicentre, observational, retrospective study we analysed data from patients treated in 39 Spanish hospitals, who started intravenous durvalumab (10 mg/kg every 2 weeks) between September 2017 and December 2018. The primary endpoint was progression-free survival (PFS). Secondary endpoints included patient characterization and adverse events of special interest (AESI). RESULTS: A total of 244 patients were followed up for a median of 21.9 months [range 1.2-34.7]. Median duration of durvalumab was 45.5 weeks (11.4 months) [0-145]. Median PFS was 16.7 months (95% CI 12.2-25). No remarkable differences in PFS were observed between patients with programmed cell death-ligand 1 (PD-L1) expression ≥ 1% or < 1% (16.7 versus 15.6 months, respectively). However, PFS was higher in patients who had received prior concurrent CRT (cCRT) versus sequential CRT (sCRT) (20.6 versus 9.4 months). AESIs leading to durvalumab discontinuation were registered in 11.1% of patients. CONCLUSIONS: These results are in line with prior published evidence and confirm the benefits of durvalumab in the treatment of LA-NSCLC patients in a real-world setting. We also observed a lower incidence of important treatment-associated toxicities, such as pneumonitis, compared with the pivotal phase III PACIFIC clinical study.

Out-of-Hospital Cardiac Arrest Following the COVID-19 Pandemic.

Importance: Out-of-hospital cardiac arrest (OHCA) health care provision may be a good indicator of the recovery of the health care system involved in OHCA care following the COVID-19 pandemic. There is a lack of data regarding outcomes capable of verifying this recovery. Objective: To determine whether return to spontaneous circulation, overall survival, and survival with good neurological outcome increased in patients with OHCA since the COVID-19 pandemic was brought under control in 2022 compared with prepandemic and pandemic levels. Design, Setting, and Participants: This observational cohort study was conducted to examine health care response and survival with good neurological outcome at hospital discharge in patients treated following OHCA. A 3-month period, including the first wave of the pandemic (February 1 to April 30, 2020), was compared with 2 periods before (April 1, 2017, to March 31, 2018) and after (January 1 to December 31, 2022) the pandemic. Data analysis was performed in July 2023. Emergency medical services (EMS) serving a population of more than 28 million inhabitants across 10 Spanish regions participated. Patients with OHCA were included if participating EMS initiated resuscitation or continued resuscitation initiated by a first responder. Exposure: The pandemic was considered to be under control following the official declaration that infection with SARS-CoV-2 was to be considered another acute respiratory infection. Main Outcome and Measures: The main outcomes were return of spontaneous circulation, overall survival, and survival at hospital discharge with good neurological outcome, expressed as unimpaired or minimally impaired cerebral performance. Results: A total of 14 732 patients (mean [SD] age, 64.2 [17.2] years; 10 451 [71.2%] male) were included, with 6372 OHCAs occurring during the prepandemic period, 1409 OHCAs during the pandemic period, and 6951 OHCAs during the postpandemic period. There was a higher incidence of OHCAs with a resuscitation attempt in the postpandemic period compared with the pandemic period (rate ratio, 4.93; 95% CI, 4.66-5.22; P < .001), with lower incidence of futile resuscitation for OHCAs (2.1 per 100 000 person-years vs 1.3 per 100 000 person-years; rate ratio, 0.81; 95% CI, 0.71-0.92; P < .001). Recovery of spontaneous circulation at hospital admission increased from 20.5% in the pandemic period to 30.5% in the postpandemic period (relative risk [RR], 1.08; 95% CI, 1.06-1.10; P < .001). In the same way, overall survival at discharge increased from 7.6% to 11.2% (RR, 1.45; 95% CI, 1.21-1.75; P < .001), with 6.6% of patients being discharged with good neurological status (Cerebral Performance Category Scale categories 1-2) in the pandemic period compared with 9.6% of patients in the postpandemic period (RR, 1.07; 95% CI, 1.04-1.10; P < .001). Conclusions and Relevance: In this cohort study, survival with good neurological outcome at hospital discharge following OHCA increased significantly after the COVID-19 pandemic.

Factors Associated with the Number of Injured and Fatalities in Motor Vehicle Intentional Mass-Casualty Incidents: A Timely Aid for Scaling the Emergency Response.

INTRODUCTION: Intentional mass-casualty incidents (IMCIs) involving motor vehicles (MVs) as weapons represent a growing trend in Western countries. This method has resulted in the highest casualty rates per incident within the field of IMCIs. Consequently, there is an urgent requirement for a timely and accurate casualty estimation in MV-induced IMCIs to scale and adjust the necessary health care resources. STUDY OBJECTIVE: The objective of this study is to identify the factors associated with the number of casualties during the initial phase of MV-IMCIs. METHODS: This is a retrospective, observational, analytical study on MV-IMCIs world-wide, from 2000-2021. Data were obtained from three different sources: Targeted Automobile Ramming Mass-Casualty Attacks (TARMAC) Attack Database, Global Terrorism Database (GTD), and the vehicle-ramming attack page from the Wikipedia website. Jacobs' formula was used to estimate the population density in the vehicle's route. The primary outcome variables were the total number of casualties (injured and fatalities). Associations between variables were analyzed using Spearman's correlation coefficient and simple linear regression. RESULTS: Forty-six MV-IMCIs resulted in 1,636 casualties (1,430 injured and 206 fatalities), most of them caused by cars. The most frequent driving pattern was accelerating whilst approaching the target, with an average speed range between four to 130km/h and a distance traveled between ten to 2,260 meters. The people estimated in the MV-IMCI scenes ranged from 36-245,717. A significant positive association was found of the number affected with the estimated crowd in the scene (R2: 0.64; 95% CI, 0.61-0.67; P <.001) and the average vehicle speed (R2: 0.42; 95% CI, 0.40-0.44; P = .004). CONCLUSION: The estimated number of people in the affected area and vehicle's average speed are the most significant variables associated with the number of casualties in MV-IMCIs, helping to enable a timely estimation of the casualties.

[Prevalence and risk factors of urinary tract infection in pregnant women]. / Prevalencia y factores de riesgo de infección del tracto urinario en embarazadas.

Background: Urinary tract infections (UTIs) are the most prevalent in pregnant women. There are associated risk factors that predispose the acquisition of a UTI in pregnancy, which can cause serious complications for mother and child. Objective: To determine the prevalence of UTI and associated risk factors in pregnant women at the Hospital Básico de Sangolquí. Material and methods: Observational, cross-sectional, analytical study conducted in 570 pregnant women from January 1 2021 to August 30 2022. The prevalence and risk factors associated with UTI were analyzed through 95% confidence intervals (95% CI) and odds ratio (OR) calculation. Results: The global prevalence of UTI in pregnant women was 37.7% (IC 95% 33.7-41.7). The most frequent etiology was Escherichia coli (65.4%), followed by Staphylococcus spp. (21.8%). The age of pregnant women ranged from 12 to 45 years, with an average of 27.55 ± 7 years, out of which those with a previous history of UTI were at greater risk of presenting UTI (OR 4.05; 95% CI 2.65-6.18), followed by diabetes mellitus (OR 2.25; 95% CI 2.48-3.44), and overweight (OR 1.48; 95% CI 1.05-2.10). Regarding gestational age, the third trimester was a protective factor for UTI (OR 0.65; 95% CI 0.46-0.92]). Conclusions: The prevalence of UTI for pregnant women was 37.7%. The most frequent etiology was Escherichia coli. A history of UTI prior to pregnancy was the main risk factor.

Introducción: las infecciones de tracto urinario (ITU) son las más prevalentes en embarazadas. Existen factores de riesgo asociados que predisponen a la adquisición de una ITU en el embarazo, las cuales pueden causar complicaciones graves para la madre y el hijo. Objetivo: determinar la prevalencia de ITU y factores de riesgo asociados en mujeres embarazadas del Hospital Básico de Sangolquí. Material y métodos: estudio observacional, transversal, analítico realizado en 570 embarazadas del 1 de enero de 2021 al 30 de agosto de 2022. La prevalencia y los factores de riesgo asociados a ITU se analizaron con intervalos de confianza del 95% (IC 95%) y razones de momios (RM). Resultados: la prevalencia global de ITU en embarazadas fue de 37.7% (IC 95%: 33.7-41.7). La etiología más frecuente fue la Escherichia coli (65.4%), seguida por Staphylococcus spp. (21.8%). La edad de las mujeres gestantes osciló entre 12 y 45 años, promedio de 27.55 ± 7 años, de las cuales presentaron mayor riesgo de ITU aquellas con antecedentes de esta infección (RM 4.05; IC 95% 2.65-6.18), seguidas por aquellas con diabetes mellitus (RM 2.25; IC 95% 2.48-3.44) y sobrepeso (RM 1.48; IC 95% 1.05-2.10). En cuanto a la edad de gestación, el tercer trimestre fue un factor protector ante las ITU (RM 0.65; IC 95% 0.46-0.92). Conclusiones: la prevalencia de ITU de las gestantes fue de 37.7%. La Escherichia coli fue la etiología más frecuente. El antecedente de ITU previa al embarazo fue el principal factor de riesgo.

Prehospital care process and hospital outcomes in stroke-code cases: comparison of basic and advance life support ambulance attendance. / Proceso de atención prehospitalaria y resultados hospitalarios del código ictus: estudio comparativo entre unidades de soporte vital básico y avanzado.

OBJECTIVES: To study prehospital care process in relation to hospital outcomes in stroke-code cases first attended by 2 different levels of ambulance. To analyze factors associated with a satisfactory functional outcome at 3 months. MATERIAL AND METHODS: Prospective multicenter observational cohort study. All stroke-code cases attended by prehospital emergency services from January 2016 to April 2022 were included. Prehospital and hospital variables were collected. The classificatory variable was type of ambulance attending (basic vs advanced life support). The main outcome variables were mortality and functional status after ischemic strokes in patients who underwent reperfusion treatment 90 days after the ischemic episode. RESULTS: Out of 22 968 stroke-code activations, ischemic stroke was diagnosed in 12 467 patients (54.3%) whose functional status was good before the episode. Basic ambulances attended 93.1%; an advanced ambulance was ordered in 1.6% of the patients. Even though there were differences in patient and clinical characteristics recorded during the prehospital process, type of ambulance was not independently associated with mortality (adjusted odds ratio [aOR], 1.1; 95% CI, 0.77-1.59) or functional status at 3 months (aOR, 1.05; 95% CI, 0,72-1,47). CONCLUSION: The percentage of patient complications in stroke-code cases attended by basic ambulance teams is low. Type of ambulance responding was not associated with either mortality or functional outcome at 3 months in this study.

OBJETIVO: Comparar el proceso asistencial prehospitalario y los resultados hospitalarios de los pacientes categorizados como Código Ictus (CI) en función del tipo de ambulancia que realiza la primera valoración, y analizar los factores asociados con un buen resultado funcional y la mortalidad a los 3 meses. METODO: Estudio observacional de cohortes prospectivo multicéntrico. Incluyó todos los CI atendidos por un sistema de emergencias prehospitalario desde enero del 2016 a abril del 2022. Se recogieron variables prehospitalarias y hospitalarias. La variable de clasificación fue el tipo de ambulancia que asiste el CI: unidad de soporte vital básico (USVB) o avanzado (USVA). Las variables de resultado principal fueron la mortalidad y el estado funcional de los ictus isquémicos sometidos a tratamiento de reperfusión a los 90 días del episodio. RESULTADOS: Se incluyeron 22.968 pacientes, de los cuales 12.467 (54,3%) presentaron un ictus isquémico con un buen estado funcional previo. El 93,1% fueron asistidos por USVB y se solicitó una USVA en el 1,6% de los casos. A pesar de presentar diferencias en el perfil clínico del paciente atendido y en los tiempos del proceso CI prehospitalario, el tipo de unidad no mostró una asociación independiente con la mortalidad (OR ajustada 1,1; IC 95%: 0,77- 1,59) ni con el estado funcional a los 3 meses (OR ajustada 1,05; IC 95%: 0,72-1,47). CONCLUSIONES: El porcentaje de complicaciones de los pacientes con CI atendidos por USVB es bajo. El tipo de unidad que asistió al paciente inicialmente no se asoció ni con el resultado funcional ni con la mortalidad a los 3 meses.

Proceso de atención prehospitalaria y resultados hospitalarios del código ictus: estudio comparativo entre unidades de soporte vital básico y avanzado / Prehospital care process and hospital outcomes in stroke-code cases: comparison of basic and advance life support ambulance attendance

Objetivos: Comparar el proceso asistencial prehospitalario y los resultados hospitalarios de los pacientes categorizados como Código Ictus (CI) en función del tipo de ambulancia que realiza la primera valoración, y analizar los factores asociados con un buen resultado funcional y la mortalidad a los 3 meses. Método: Estudio observacional de cohortes prospectivo multicéntrico. Incluyó todos los CI atendidos por un sistema de emergencias prehospitalario desde enero del 2016 a abril del 2022. Se recogieron variables prehospitalarias y hospitalarias. La variable de clasificación fue el tipo de ambulancia que asiste el CI: unidad de soporte vital básico (USVB) o avanzado (USVA). Las variables de resultado principal fueron la mortalidad y el estado funcional de los ictus isquémicos sometidos a tratamiento de reperfusión a los 90 días del episodio. Resultados: Se incluyeron 22.968 pacientes, de los cuales 12.467 (54,3%) presentaron un ictus isquémico con un buen estado funcional previo. El 93,1% fueron asistidos por USVB y se solicitó una USVA en el 1,6% de los casos. A pesar de presentar diferencias en el perfil clínico del paciente atendido y en los tiempos del proceso CI prehospitalario, el tipo de unidad no mostró una asociación independiente con la mortalidad (OR ajustada 1,1; IC 95%: 0,77-1,59) ni con el estado funcional a los 3 meses (OR ajustada 1,05; IC 95%: 0,72-1,47). Conclusiones: El porcentaje de complicaciones de los pacientes con CI atendidos por USVB es bajo. El tipo de unidad que asistió al paciente inicialmente no se asoció ni con el resultado funcional ni con la mortalidad a los 3 meses. (AU)

Objectives: To study prehospital care process in relation to hospital outcomes in stroke-code cases first attended by 2 different levels of ambulance. To analyze factors associated with a satisfactory functional outcome at 3 months. Methods: Prospective multicenter observational cohort study. All stroke-code cases attended by prehospital emergency services from January 2016 to April 2022 were included. Prehospital and hospital variables were collected. The classificatory variable was type of ambulance attending (basic vs advanced life support). The main outcome variables were mortality and functional status after ischemic strokes in patients who underwent reperfusion treatment 90 days after the ischemic episode. Results: Out of 22 968 stroke-code activations, ischemic stroke was diagnosed in 12 467 patients (54.3%) whose functional status was good before the episode. Basic ambulances attended 93.1%; an advanced ambulance was ordered in 1.6% of the patients. Even though there were differences in patient and clinical characteristics recorded during the prehospital process, type of ambulance was not independently associated with mortality (adjusted odds ratio [aOR], 1.1; 95% CI, 0.77-1.59) or functional status at 3 months (aOR, 1.05; 95% CI, 0,72-1,47). Conclusions: The percentage of patient complications in stroke-code cases attended by basic ambulance teams is low. Type of ambulance responding was not associated with either mortality or functional outcome at 3 months in this study. (AU)

Prehospital stratification and prioritisation of non-ST-segment elevation acute coronary syndrome patients (NSTEACS): the MARIACHI scale.

OBJECTIVE: The objective of this study was to develop and validate a risk scale (MARIACHI) for patients classified as non-ST-segment elevation acute coronary syndrome (NSTEACS) in a prehospital setting with the ability to identify patients at an increased risk of mortality at an early stage. METHODS: A retrospective observational study conducted in Catalonia over two periods: 2015-2017 (development and internal validation cohort) and Aug 2018-Jan 2019 (external validation cohort). We included patients classified as prehospital NSTEACS, assisted by an advanced life support unit and requiring hospital admission. The primary outcome was in-hospital mortality. Cohorts were compared using logistic regression and a predictive model was created using bootstrapping techniques. RESULTS: The development and internal validation cohort included 519 patients. The model is composed of five variables associated with hospital mortality: age, systolic blood pressure, heart rate > 95 bpm, Killip-Kimball III-IV and ST depression ≥ 0.5 mm. The model showed good overall performance (Brier = 0.043) and consistency in discrimination (AUC 0.88, 95% CI 0.83-0.92) and calibration (slope = 0.91; 95% CI 0.89-0.93). We included 1316 patients for the external validation sample. There was no difference in discrimination (AUC 0.83, 95% CI 0.78-0.87; DeLong Test p = 0.071), but there was in calibration (p < 0.001), so it was recalibrated. The finally model obtained was stratified and scored into three groups according to the predicted risk of patient in-hospital mortality: low risk: < 1% (-8 to 0 points), moderate risk: 1-5% (+ 1 to + 5 points) and high risk: > 5% (6-12 points). CONCLUSION: The MARIACHI scale showed correct discrimination and calibration to predict high-risk NSTEACS. Identification of high-risk patients may help with treatment and low referral decisions at the prehospital level.

Combined Intake of Fish Oil and D-Fagomine Prevents High-Fat High-Sucrose Diet-Induced Prediabetes by Modulating Lipotoxicity and Protein Carbonylation in the Kidney.

Obesity has been recognized as a major risk factor for chronic kidney disease, insulin resistance being an early common metabolic feature in patients suffering from this syndrome. This study aims to investigate the mechanism underlying the induction of kidney dysfunction and the concomitant onset of insulin resistance by long-term high-fat and sucrose diet feeding in Sprague Dawley rats. To achieve this goal, our study analyzed renal carbonylated protein patterns, ectopic lipid accumulation and fatty acid profiles and correlated them with biometrical and biochemical measurements and other body redox status parameters. Rats fed the obesogenic diet developed a prediabetic state and incipient kidney dysfunction manifested in increased plasma urea concentration and superior levels of renal fat deposition and protein carbonylation. An obesogenic diet increased renal fat by preferentially promoting the accumulation of saturated fat, arachidonic, and docosahexaenoic fatty acids while decreasing oleic acid. Renal lipotoxicity was accompanied by selectively higher carbonylation of proteins involved in the blood pH regulation, i.e., bicarbonate reclamation and synthesis, amino acid, and glucose metabolisms, directly related to the onset of insulin resistance. This study also tested the combination of antioxidant properties of fish oil with the anti-diabetic properties of buckwheat D-Fagomine to counteract diet-induced renal alterations. Results demonstrated that bioactive compounds combined attenuated lipotoxicity, induced more favorable lipid profiles and counteracted the excessive carbonylation of proteins associated with pH regulation in the kidneys, resulting in an inhibition of the progression of the prediabetes state and kidney disease.

Plants maintain climate fidelity in the face of dynamic climate change.

Plants will experience considerable changes in climate within their geographic ranges over the next several decades. They may respond by exhibiting niche flexibility and adapting to changing climates. Alternatively, plant taxa may exhibit climate fidelity, shifting their geographic distributions to track their preferred climates. Here, we examine the responses of plant taxa to changing climates over the past 18,000 y to evaluate the extent to which the 16 dominant plant taxa of North America have exhibited climate fidelity. We find that 75% of plant taxa consistently exhibit climate fidelity over the past 18,000 y, even during the times of most extreme climate change. Of the four taxa that do not consistently exhibit climate fidelity, three-elm (Ulmus), beech (Fagus), and ash (Fraxinus)-experience a long-term shift in their realized climatic niche between the early Holocene and present day. Plant taxa that migrate longer distances better maintain consistent climatic niches across transition periods during times of the most extreme climate change. Today, plant communities with the highest climate fidelity are found in regions with high topographic and microclimate heterogeneity that are expected to exhibit high climate resilience, allowing plants to shift distributions locally and adjust to some amount of climate change. However, once the climate change buffering of the region is exceeded, these plant communities will need to track climates across broader landscapes but be challenged to do so because of the low habitat connectivity of the regions.

Late quaternary biotic homogenization of North American mammalian faunas.

Biotic homogenization-increasing similarity of species composition among ecological communities-has been linked to anthropogenic processes operating over the last century. Fossil evidence, however, suggests that humans have had impacts on ecosystems for millennia. We quantify biotic homogenization of North American mammalian assemblages during the late Pleistocene through Holocene (~30,000 ybp to recent), a timespan encompassing increased evidence of humans on the landscape (~20,000-14,000 ybp). From ~10,000 ybp to recent, assemblages became significantly more homogenous (>100% increase in Jaccard similarity), a pattern that cannot be explained by changes in fossil record sampling. Homogenization was most pronounced among mammals larger than 1 kg and occurred in two phases. The first followed the megafaunal extinction at ~10,000 ybp. The second, more rapid phase began during human population growth and early agricultural intensification (~2,000-1,000 ybp). We show that North American ecosystems were homogenizing for millennia, extending human impacts back ~10,000 years.

A colorimetric method to measure in vitro nitrogenase functionality for engineering nitrogen fixation.

Biological nitrogen fixation (BNF) is the reduction of N2 into NH3 in a group of prokaryotes by an extremely O2-sensitive protein complex called nitrogenase. Transfer of the BNF pathway directly into plants, rather than by association with microorganisms, could generate crops that are less dependent on synthetic nitrogen fertilizers and increase agricultural productivity and sustainability. In the laboratory, nitrogenase activity is commonly determined by measuring ethylene produced from the nitrogenase-dependent reduction of acetylene (ARA) using a gas chromatograph. The ARA is not well suited for analysis of large sample sets nor easily adapted to automated robotic determination of nitrogenase activities. Here, we show that a reduced sulfonated viologen derivative (S2Vred) assay can replace the ARA for simultaneous analysis of isolated nitrogenase proteins using a microplate reader. We used the S2Vred to screen a library of NifH nitrogenase components targeted to mitochondria in yeast. Two NifH proteins presented properties of great interest for engineering of nitrogen fixation in plants, namely NifM independency, to reduce the number of genes to be transferred to the eukaryotic host; and O2 resistance, to expand the half-life of NifH iron-sulfur cluster in a eukaryotic cell. This study established that NifH from Dehalococcoides ethenogenes did not require NifM for solubility, [Fe-S] cluster occupancy or functionality, and that NifH from Geobacter sulfurreducens was more resistant to O2 exposure than the other NifH proteins tested. It demonstrates that nitrogenase components with specific biochemical properties such as a wider range of O2 tolerance exist in Nature, and that their identification should be an area of focus for the engineering of nitrogen-fixing crops.

Effect of a prioritization score on the inter-hospital transfer time management of severe COVID-19 patients: a quasi-experimental intervention study.

BACKGROUND: The overburdening of the healthcare system during the coronavirus disease 19 (COVID-19) pandemic is driving the need to create new tools to improve the management of inter-hospital transport for patients with a severe COVID-19 infection. OBJECTIVE: The aim of this study was to analyse the usefulness of the application of a prioritization score (IHTCOVID-19) for inter-hospital transfer of patients with COVID-19 infection. METHODS: The study has a quasi-experimental design and was conducted on the Medical Emergency System, the pre-hospital emergency department of the public company belonging to the Autonomous Government of Catalonia that manages urgent healthcare in the region. Patients with a severe COVID-19 infection requiring inter-hospital transport were consecutively included. The pre-intervention period was from 1 to 31 March 2020, and the intervention period with the IHTCOVID-19 score was from 1 to 30 April 2020 (from 8 am to 8 pm). The prioritization score comprises four priority categories, with Priority 0 being the highest and Priority 3 being the lowest. Inter-hospital transfer (IHT) management times (alert-assignment time, resource management time and total central management time) and their variability were evaluated according to whether or not the IHTCOVID-19 score was applied. RESULTS: A total of 344 IHTs were included: 189 (54.9%) in the pre-intervention period and 155 (45.1%) in the post-intervention period. The majority of patients were male and the most frequent age range was between 50 and 70 years. According to the IHTCOVID-19 score, 12 (3.5%) transfers were classified as Priority 0, 66 (19.4%) as Priority 1, 247 (71.8%) as Priority 2 and 19 (5.6%) as Priority 3. Overall, with the application of the IHTCOVID-19 score, there was a significant reduction in total central management time [from 112.4 (inter-quartile range (IQR) 281.3) to 89.8 min (IQR 154.9); P = 0.012]. This significant reduction was observed in Priority 0 patients [286.2 (IQR 218.5) to 42.0 min (IQR 58); P = 0.018] and Priority 1 patients [130.3 (IQR 297.3) to 75.4 min (IQR 91.1); P = 0.034]. After applying the IHTCOVID-19 score, the average time of the process decreased by 22.6 min, and variability was reduced from 618.1 to 324.0 min. CONCLUSION: The application of the IHTCOVID-19 score in patients with a severe COVID-19 infection reduces IHT management times and variability.

Dietary niches of creodonts and carnivorans of the late Eocene Cypress Hills Formation.

Modern North American carnivorous mammal assemblages consist of species from a single clade: the Carnivora. Carnivorans once coexisted with members of other meat-eating clades, including the creodonts (Hyaenodontida and Oxyaenida). Creodonts, however, went extinct in North America during the late Eocene and early Oligocene, potentially due to niche overlap and resource competition with contemporary carnivorans. In this study, we employ a community ecology approach to understand whether the dietary niches of coexisting creodonts and carnivorans overlapped during the late Eocene (Chadronian North American Land Mammal Age), a time when creodonts were dwindling and carnivorans were diversifying. We quantify niche overlap based on inferences of diet from carnassial tooth shape estimated using Orientation Patch Count, Dirichlet's Normal Surface Energy, and linear dental measurements as well as from body mass for all species in the Calf Creek Local Fauna of Cypress Hills, Saskatchewan (Treaty 4 land). Although creodonts and carnivorans shared characteristics of their carnassial tooth shape, suggesting similar chewing mechanics and feeding habits, we find that marked differences in body size likely facilitated niche partitioning, at least between the largest creodonts and carnivorans. Calculations of prey focus masses and prey mass spectra indicate that only the smallest creodont may have experienced significant competition for prey with the coeval carnivorans. We suggest that the ultimate extinction of creodonts from North America during the late Eocene and Oligocene was unlikely to have been driven by factors related to niche overlap with carnivorans.