The geodynamic origin of Los Humeros volcanic field in Mexico: insights from numerical simulations

Compared to normal arc-related volcanic eruptions, the formation of a volcanic caldera is a relatively atypical event. During caldera formation a series of large volumes of magma are erupted, reducing the structural support for the rock above the magma chamber and creating a large depression at the surface called caldera. Los Humeros volcanic field (LHVF) represents one of the largest volcanic calderas in Mexico. It is located some 400 km from the trench at the eastern edge of the Trans Mexican Volcanic Belt where the depth to the Cocos slab is more than 300 km. In this study we employ high-resolution two-dimensional thermomechanical numerical simulations of magma intrusions and a horizontal tectonic strain rate to better understand the influence of crustal deformation for the formation of Los Humeros caldera. A minimum number of three thermal anomaly pulses of hydrated mantle material (with diameter of 15 km or more) and a regional strain rate of 7.927 × 10-16 s-1 are required for magma to reach the surface. Modeling results show that regional extension coupled with deep thermal anomalies (with a temperature excess of ΔT ≥ 100 °C) that come in a specific chain-type sequence produce surface deformation patterns similar to LHVF. We propose an asthenospheric sub-slab deep source (> 300 km depth) for the thermal anomalies where previous studies showed the existence of a gap or tear in the Cocos slab.

A review of three decades of use of the cattle brucellosis rough vaccine Brucella abortus RB51: myths and facts

Cattle brucellosis is a severe zoonosis of worldwide distribution caused by Brucella abortus and B. melitensis. In some countries with appropriate infrastructure, animal tagging and movement control, eradication was possible through efficient diagnosis and vaccination with B. abortus S19, usually combined with test-and-slaughter (T/S). Although S19 elicits anti-smooth lipopolysaccharide antibodies that may interfere in the differentiation of infected and vaccinated animals (DIVA), this issue is minimized using appropriate S19 vaccination protocols and irrelevant when high-prevalence makes mass vaccination necessary or when eradication requisites are not met. However, S19 has been broadly replaced by vaccine RB51 (a rifampin-resistant rough mutant) as it is widely accepted that is DIVA, safe and as protective as S19. These RB51 properties are critically reviewed here using the evidence accumulated in the last 35 years. Controlled experiments and field evidence shows that RB51 interferes in immunosorbent assays (iELISA, cELISA and others) and in complement fixation, issues accentuated by revaccinating animals previously immunized with RB51 or S19. Moreover, contacts with virulent brucellae elicit anti-smooth lipopolysaccharide antibodies in RB51 vaccinated animals. Thus, accepting that RB51 is truly DIVA results in extended diagnostic confusions and, when combined with T/S, unnecessary over-culling. Studies supporting the safety of RB51 are flawed and, on the contrary, there is solid evidence that RB51 is excreted in milk and abortifacient in pregnant animals, thus being released in abortions and vaginal fluids. These problems are accentuated by the RB51 virulence in humans, lack diagnostic serological tests detecting these infections and RB51 rifampicin resistance. In controlled experiments, protection by RB51 compares unfavorably with S19 and lasts less than four years with no evidence that RB51-revaccination bolsters immunity, and field studies reporting its usefulness are flawed. There is no evidence that RB51 protects cattle against B. melitensis, infection common when raised together with small ruminants. Finally, data acumulated during cattle brucellosis eradication in Spain shows that S19-T/S is far more efficacious than RB51-T/S, which does not differ from T/S alone. We conclude that the assumption that RB51 is DIVA, safe, and efficaceous results from the uncritical repetition of imperfectly examined evidence, and advise against its use.

Discovery of Gamma Rays from the Quiescent Sun with HAWC

We report the first detection of a TeV γ-ray flux from the solar disk (6.3σ), based on 6.1 years of data from the High Altitude Water Cherenkov (HAWC) observatory. The 0.5-2.6 TeV spectrum is well fit by a power law, dN/dE=A(E/1  TeV)^{-γ}, with A=(1.6±0.3)×10^{-12}  TeV^{-1} cm^{-2} s^{-1} and γ=3.62±0.14. The flux shows a strong indication of anticorrelation with solar activity. These results extend the bright, hard GeV emission from the disk observed with Fermi-LAT, seemingly due to hadronic Galactic cosmic rays showering on nuclei in the solar atmosphere. However, current theoretical models are unable to explain the details of how solar magnetic fields shape these interactions. HAWC's TeV detection thus deepens the mysteries of the solar-disk emission.

Marine records reveal multiple phases of Toba's last volcanic activity

The Indonesian Young Toba Tuff (YTT), classically dated around 74 ka BP, is considered as a short-lived explosive cataclysmic super-eruption. The huge amounts of ash and SO₂ emitted are likely to have triggered a volcanic winter which accelerated the transition to the last glaciation, and may have induced a human genetic bottleneck. However, the global climatic impact of the YTT or its duration are hotly debated. The present work offers a new interpretation of the Toba volcanic complex eruptive history. Analysing the BAR94-25 marine core proximal to the Toba volcanic center and combining it with high-resolution tephrostratigraphy and δ¹⁸O stratigraphy, we show that the Toba complex produced a volcanic succession that consists of at least 17 distinct layers of tephra and cryptotephra. Textural and geochemical analyses show that the tephra layers can be divided in 3 main successive volcanic activity phases (VAP1 to VAP3) over a period of ~ 50 kyr. The main volcanic activity phase, VAP2, including the YTT, is likely composed of 6 eruptive events in an interval whose total duration is ~ 10 ka. Thus, we suggest that the eruptive model of the Toba volcano must be revised as the duration of the Toba volcanic activity was much longer than suggested by previous studies. The implications of re-estimating the emission rate and the dispersion of ashes and SO₂ include global environmental reconstitutions, climate change modelling and possibly human migration and evolution.

Patient preferences in chronic immune-mediated inflammatory diseases potentially treated with biological drugs: discrete choice analysis using real-world data analysis

OBJECTIVES

Immune-mediated inflammatory diseases (IMIDs) represent a high burden due to their chronicity, high prevalence, and associated comorbidities. Chronic patients' preferences must be considered in IMIDs treatment and follow-up. The objective of this study was to further understand patient's preferences in private settings.

METHODS

A literature review was performed to choose the most relevant criteria for patients. A D-efficient discrete choice experiment was designed to elicit preferences of adult patients with IMIDs and potential biological treatment prescription. Participants were collected from private practices (rheumatology, dermatology, and gastroenterology) from February to May 2022. Patients chose between option pairs, characterized by six health-care attributes, as well as monthly out-of-pocket drug price. Responses were analyzed through a conditional logit model.

RESULTS

Eighty-seven patients answered the questionnaire. The most frequent pathologies were Rheumatoid Arthritis (31%) and Psoriatic Arthritis (26%). The most relevant criteria were choosing the preferred physician (OR 2.25 [SD0.26]); reducing time until visit with specialist (OR 1.79 [SD0.20]), access through primary care (OR 1.60 [SD0.08]), and an increase in monthly out-of-pocket price from 100€ to 300€ (OR 0.55 [SD0.06]) and to 600€ (OR 0.08 [SD0.02]).

CONCLUSIONS

Chronic IMIDs patients showed a preference toward a faster, personalized service, even with a trade-off in terms of out-of-pocket price.

Quality of life and persistent symptoms after hospitalization for COVID-19. A prospective observational study comparing ICU with non-ICU patients

Background

Hospitalized COVID-19 patients are prone to develop persistent symptoms and to show reduced quality of life following hospital admission.

Methods

Prospective cohort study of COVID-19 patients admitted to a hospital from March 1 to April 30, 2020. The primary outcome was to compare health related quality of life and persistent symptoms six months after hospital admission, of COVID-19 patients who required ICU admission with those who did not.

Results

Among the 242 patients hospitalized during the defined period of time, 44 (18.2%) needed ICU admission. Forty (16.5%) patients died during hospital admission. Two hundred and two (83.5%) patients were discharged alive from the hospital. At six months, 183 (75.6%) patients completed the questionnaires (32 ICU patients and 151 non ICU patients). Ninety-six (52.4%) reported decreased quality of life and 143 (78.1%) described persistent symptoms. More ICU patients showed worsening of their quality of life (71.9% vs 43.7%, P = 0.004). There were no differences in the proportion of patients with persistent symptoms between ICU and non ICU patients (87.5% vs 76.2%, P = 0.159). ICU patients showed more frequently dyspnea on exertion (78.1% vs 47.7%, P = 0.02), dyspnea on light exertion (37.5% vs 4.6%, P < 0.001), and asthenia (56.3 vs 29.1, P = 0.003).

Conclusions

Survivors of COVID-19 needing hospitalization had persistent symptoms and a decline in the quality of life. ICU patients referred a large decrease of their quality of life compared with non ICU patients.

A prospective study of costs associated with the evaluation of allergic reactions to radiological contrast media

BACKGROUND AND OBJECTIVE

The prevalence of hypersensitivity reactions to radiological contrast media (RCM) is increasing due to the greater performance of diagnostic and therapeutic tests that require RCMs. Objective: We carried out a year-long real-life observational study to prospectively evaluate the patients referred to the Allergy Service from Primary Care, Emergency Room, and other Services with suspected moderate to severe RCM hypersensitivity.

METHODS

To study the costs of RCM hypersensitivity evaluation, we systematically recorded direct and indirect costs.

RESULTS

Sixty-nine patients with previous reactions to RCM were evaluated in the Allergy Service from June 1st, 2017, to May 31st, 2018. Total direct health care costs were € 10715.84, with a mean cost per patient of € 155.30 ± 77.08. Specifically, direct non-health costs reached € 1605.42 (mean € 23.27 ± 41.14), and indirect costs were € 6490.85 (mean € 94.07 ± 110.61). In summary, the total cost was € 18812.11, which means a mean cost of € 272.64 ± 164.77.

CONCLUSION

Our study reflects that the costs of an elective evaluation of hypersensitivity to RCM are low. This fact reaffirms that correct and safe management of these patients could be cost-effective, so our efforts should be directed to implement the necessary logistics.

Active Versus Passive Flow Control in UVC FILTERs for COVID-19 Containment

Ultraviolet radiation as a germicide is widely used in the health field and even in domestic hygiene. Here, we propose an improvement in low-cost portable units of filtration for indoor air, which is based on ultraviolet radiation. In the current technology, to carry out an air filtration with a suspension of aerosols in which there is a likely concentration of pathogens, whether viral, bacterial or molds, the air is forced to pass as close as possible to the ionizing radiation source (near field). Since the optical mass is very small, the desired effect can be achieved in a considerably short time, deactivating the infective potential of these biological agents. The proposal of this work is the regulation of the flow or speed control of passage through these filters by passive elements instead of by electronic control systems. For this, two devices have been designed, simulated, and built, obtaining similar net pathogen inactivation rates under different flow rates. The passive flow control device has demonstrated higher performance in terms of flow rate and lower cost of production since they do not require electronics and are produced with fewer diodes. This passive device has also shown a lower projection of maintenance cost, lower energy consumption rate (higher efficiency), and longer projection of useful life.

Dupilumab: a Review of Present Indications and Uses Out Of Indication

Recent advances in understanding T2 inflammation have broadened the diseases in which T2 inflammation can be involved. Dupilumab is a recently developed monoclonal antibody blocking the signaling of both IL-4 and IL13, two crucial cytokines of the T2 responses. New possible indications are increasingly exploring. Among them are skin diseases, such as prurigo nodularis, nummular eczema, allergic contact dermatitis, chronic hand eczema, spontaneous chronic urticaria, bullous pemphigoid, alopecia areata, and Netherton syndrome, among other several cutaneous diseases. Also, respiratory diseases, such as allergic bronchopulmonary aspergillosis, chronic eosinophilic pneumonia, and allergic rhinitis. In addition, eosinophilic gastrointestinal disorders, particularly eosinophilic esophagitis, and food allergy are two more research fields. Here we review the published data and clinical trials about the use of dupilumab in these disorders.

Clinical Practice Guidelines for Diagnosis and Management of Hypersensitivity Reactions to Quinolones

The consumption of quinolones as first-line treatment has increased in recent years, leading to an increase in the incidence of hypersensitivity reactions (HSRs) to this antibiotic group. Both diagnosis and management of HSRs to quinolones are complex and controversial. These practical guidelines aim to provide recommendations for effective clinical practice. The recommendations were drafted by an expert panel that reviewed the literature regarding HSRs to quinolones and analyzed controversies in this area. Most HSRs to quinolones are immediate and severe. The risk for HSRs is higher in patients who report allergy to ß-lactams, moxifloxacininduced anaphylaxis, and immediate reactions than in patients who report reactions to quinolones inducing other symptoms. The usefulness of skin tests in diagnosing HSRs to quinolones is controversial, with sensitivity and specificity varying between studies. Most in vitro tests are produced in-house, with no validated commercial options. The basophil activation test has proven useful for diagnosing immediate reactions, albeit with diverse results regarding sensitivity. Drug provocation testing is currently the gold standard for confirming or excluding the diagnosis and for finding safe alternatives, although it is contraindicated in patients with severe reactions. Cross-reactivity between quinolones has proven controversial in several studies, with the lowest cross-reactivity reported for levofloxacin. Desensitization may be considered in allergy to quinolones when no other alternatives are available.

Critically ill COVID-19 patients attended by anesthesiologists in northwestern Spain: a multicenter prospective observational study

BACKGROUND AND OBJECTIVES

There are limited information on outcome, complications and treatments of critically ill COVID-19 patients requiring admission to an intensive care unit (ICU). The aim of this study is to describe the clinical ICU course, treatments used, complications and outcomes, of critically ill COVID-19 patients admitted in seven ICU in Galicia region during the 2020 March-April pandemic peak.

METHODS

Between March 21 and April 19, 2020, we evaluated critically ill COVID-19 patients admitted to the ICU of Anesthesia of seven hospitals in Galicia, northwestern Spain. Outcome, complications, and treatments were monitored until May 6, 2020, the final date of follow-up.

RESULTS

A total of 97 critically ill COVID-19 patients were included. During ICU stay, mechanical ventilation became necessary in 80 (82.5%) patients, and tracheostomy in 22 (22.7%) patients. Prone position was used frequently in both intubated (67.5%) and awake (27.8%) patients. Medications consisted of antivirals agents (92.7%), corticosteroids (93.8%), tocilizumab (57.7%), and intermediate or high doses of anticoagulants (83.5%). The most frequent complications were ICU-acquired infection (52.6%), thrombosis events (16.5%), and reintubation (9.3%). After a median follow-up of 42 (34-45) days, 15 patients (15.5%) deceased, 73 patients (75.2%) had been discharged from ICU, and nine patients (9.3%) were still in the ICU.

CONCLUSIONS

A high proportion of our critically ill COVID-19 patients required mechanical ventilation, prone positioning, antiviral medication, corticosteroids, and anticoagulants. ICU complications were frequent, mainly infections and thrombotic events. We had a relatively low mortality of 15,5%.

Constraints on Lorentz Invariance Violation from HAWC Observations of Gamma Rays above 100 TeV

Because of the high energies and long distances to the sources, astrophysical observations provide a unique opportunity to test possible signatures of Lorentz invariance violation (LIV). Superluminal LIV enables the decay of photons at high energy. The high altitude water Cherenkov (HAWC) observatory is among the most sensitive gamma-ray instruments currently operating above 10 TeV. HAWC finds evidence of 100 TeV photon emission from at least four astrophysical sources. These observations exclude, for the strongest of the limits set, the LIV energy scale to 2.2×10^{31}  eV, over 1800 times the Planck energy and an improvement of 1 to 2 orders of magnitude over previous limits.

When the Ice Has Gone: Colonisation of Equatorial Glacier Forelands by Ground Beetles (Coleoptera: Carabidae)

Ground beetles (Coleoptera: Carabidae) are among the early colonisers of recently deglaciated terrains. While patterns of carabid colonisation along forelands of retreating glaciers have been thoroughly investigated in temperate climates, information remains scarce in tropical mountains. This study aimed to describe for the first time the carabid beetle species assemblages along the chronosequence of two tropical Andean glaciers (Antisana and Carihuairazo, Ecuador). Shannon index, taxonomic distinctness and species assemblage composition did not reveal deterministic and directional patterns. Only the principal coordinate analysis performed on the Antisana dataset showed that some species had a clear preference for terrains deglaciated for more than 200 years. Our results showed that equatorial glacier forelands are colonised by pioneer species that persist from the recently deglaciated terrains (less than 25 years) to terrains deglaciated since more than 200 years. This pattern fits the 'addition and persistence model' of high-latitude glacier forelands, rather than the 'species replacement model' of the Alps. The pioneer species observed are high-altitude specialists adapted to constantly cold environments, but not specifically ice-related. In the current context of climate warming, pioneer and cold-adapted species living near the glaciers of equatorial mountains are therefore only threatened by the 'summit trap' risk, unlike in temperate regions, as they are not strictly linked to the glacier microclimate.

Unipolar resistive switching behavior in Al2O3/HfO2 multilayer dielectric stacks: fabrication, characterization and simulation

In this work, the impact of different HfO₂/Al₂O₃-based multilayer dielectric stack (DS) configurations on the electrical characteristics and on the resistive switching (RS) performance of Ni/Insulator/Silicon devices has been systematically investigated. Significant differences are observed in the electrical characteristics of the fabricated bilayer, trilayer and pentalayer stacks compared to a single HfO₂ layer of the same physical thickness. The RS analysis has shown similar low resistance state currents and set voltages for all the DS combinations whereas currents at the high resistance state and reset voltages depend on the DS. The shift of the reset voltage to lower values for HfO₂ and Al₂O₃/HfO₂/Al₂O₃ cases is explained by the results from thermal simulations that reveal that these differences could be associated to the different temperature distributions at the narrowest part of the conductive filament immediately before the thermally triggered reset process occurs.

Multiple Galactic Sources with Emission Above 56 TeV Detected by HAWC

We present the first catalog of gamma-ray sources emitting above 56 and 100 TeV with data from the High Altitude Water Cherenkov Observatory, a wide field-of-view observatory capable of detecting gamma rays up to a few hundred TeV. Nine sources are observed above 56 TeV, all of which are likely galactic in origin. Three sources continue emitting past 100 TeV, making this the highest-energy gamma-ray source catalog to date. We report the integral flux of each of these objects. We also report spectra for three highest-energy sources and discuss the possibility that they are PeVatrons.

A Comprehensive Prospective Study of the Costs Associated With Evaluation of ß-Lactam Allergy

BACKGROUND AND OBJECTIVE

Being labeled as allergic to penicillin (unverified ß-lactam allergy) can result in patients receiving broader-spectrum antibiotics than necessary that may be more toxic, less effective, and/or more expensive than alternative options. Objective: We aimed to evaluate the real costs of evaluating ß-lactam allergy.

METHODS

We performed a prospective real-life observational study designed to evaluate all adult patients who consulted for suspected ß-lactam allergy over a 1-year period. Direct and indirect costs were systematically recorded. Direct health costs were calculated based on the number of visits and all additional and diagnostic tests performed, direct nonhealth costs based on the number of visits and the distance from their homes to the Allergy Department, and indirect costs based on absenteeism.

RESULTS

A total of 296 patients with suspected allergy to ß-lactams were evaluated in our outpatient clinic from June 1, 2017 to May 31, 2018. Total direct health care costs were €28 176.70, with a mean (SD) cost of €95.19 (37.20). Direct nonhealth costs reached €6551.73, that is, €22.13 (40.44) per patient. Indirect health costs reached €20 769.20, with a mean of €70.17 (127.40). In summary, the total cost was €55 497.63, that is, a cost per patient of €187.49 (148.14).

CONCLUSIONS

When all possible costs are taken into account, the evaluation of ß-lactam allergy is not expensive and can reduce future expense arising from unnecessary use of more expensive and less effective antibiotics.

Broad band high resolution rotational spectroscopy for Laboratory Astrophysics

We present a new experimental setup devoted to the study of gas phase molecules and processes using broad band high spectral resolution rotational spectroscopy. A reactor chamber has been equipped with radio receivers similar to those used by radio astronomers to search for molecular emission in space. The whole Q (31.5-50 GHz) and W bands (72-116.5 GHz) are available for rotational spectroscopy observations. The receivers are equipped with 16×2.5 GHz Fast Fourier Transform spectrometers with a spectral resolution of 38.14 kHz allowing the simultaneous observation of the complete Q band and one third of the W band. The whole W band can be observed in three settings in which the Q band is always observed. Species such as CH3CN, OCS, and SO2 are detected, together with many of their isotopologues and vibrationally excited states, in very short observing times. The system permits automatic overnight observations and integration times as long as 2.4×105 seconds have been reached. The chamber is equipped with a radiofrequency source to produce cold plasmas and with four ultraviolet lamps to study photochemical processes. Plasmas of CH4, N2, CH3CN, NH3, O2, and H2, among other species, have been generated and the molecular products easily identified by their rotational spectrum, and mass spectrometry and optical spectroscopy. Finally, the rotational spectrum of the lowest energy conformer of CH3CH2NHCHO (N-Ethylformamide), a molecule previously characterized in microwave rotational spectroscopy, has been measured up to 116.5 GHz allowing the accurate determination of its rotational and distortion constants and its search in space.

Early outcome of a 31-gene expression profile test in 86 AJCC stage IB-II melanoma patients. A prospective multicentre cohort study

Background

The clinical and pathological features of primary melanoma are not sufficiently sensitive to accurately predict which patients are at a greater risk of relapse. Recently, a 31‐gene expression profile (DecisionDx‐Melanoma) test has shown promising results.

Objectives

To evaluate the early prognostic performance of a genetic signature in a multicentre prospectively evaluated cohort.

Methods

Inclusion of patients with AJCC stages IB and II conducted between April 2015 and December 2016. All patients were followed up prospectively to assess their risk of relapse. Prognostic performance of this test was evaluated individually and later combined with the AJCC staging system. Prognostic accuracy of disease‐free survival was determined using Kaplan–Meier curves and Cox regression analysis. Results of the gene expression profile test were designated as Class 1 (low risk) and Class 2 (high risk).

Results

Median follow‐up time was 26 months (IQR 22–30). The gene expression profile test was performed with 86 patients; seven had developed metastasis (8.1%) and all of them were in the Class 2 group, representing 21.2% of this group. Gene expression profile was an independent prognostic factor for relapse as indicated by multivariate Cox regression analysis, adjusted for AJCC stages and age.

Conclusions

This prospective multicentre cohort study, performed in a Spanish Caucasian cohort, shows that this 31‐gene expression profile test could correctly identify patients at early AJCC stages who are at greater risk of relapse. We believe that gene expression profile in combination with the AJCC staging system could well improve the detection of patients who need intensive surveillance and optimize follow‐up strategies.

Three-dimensional skeletal changes after early proportional condylectomy for condylar hyperplasia

The purpose of this study was to evaluate volumetric and dentoskeletal changes in 21 patients with active unilateral condylar hyperplasia (AUCH) after proportional condylectomy. A split-mouth design was used: control group healthy joints (HS, healthy side) and test group affected joints (AS, affected side) (21 per group). Cone beam tomography scans were obtained at T0 (preoperative), T1 (10days after the intervention), and T2 (approximately 12 months post-surgery). The condylar unit volume (CUV), articular cavity volume (ACV), and dentoalveolar units (DAUs) were measured. CUV showed a difference of 1.12cm³ between T0 and T1, increasing 0.4cm³ between T1 and T2 on AS. There was no difference between T0 and T2 on HS. ACV increased 0.65cm³ between T0 and T1 on AS, after which it decreased by 0.36cm³ at T2 (0.30cm³ larger than the initial articular cavity at T0). ACV showed no post-surgery differences on HS. Midline DAU showed extrusion of 0.20mm for maxilla and 0.52mm for mandible, while in the lateral area, maxilla was extruded by 0.3mm on HS and was intruded 0.12mm on AS. For the mandible, both sides showed extrusion (0.4-0.6mm). In the distal to canine and molar areas, intrusion of 0.2mm and 0.9mm, respectively, was observed on AS; there was extrusion of 0.6mm distal to the canine on HS. At the mandibular level, AS distal to the canine showed extrusion of 1mm, while intrusion of 0.2mm was observed in the molars. For HS, only extrusion at the molar level (0.2mm) was observed. In conclusion, after proportional condylectomy, a neocondyle forms within 12 months to equal the healthy contralateral side. The articular cavity, which is reduced in the initial stage, increases in size after surgery and the volume gradually approaches that of the healthy side. Dentoalveolar changes occur at the anterior and posterior levels, causing intrusion and extrusion of the interdental crests. An early proportional condylectomy as the sole surgical treatment for patients with AUCH allows normalization of the maxillomandibular relationship.

Publisher Correction: Very-high-energy particle acceleration powered by the jets of the microquasar SS 433

In this Letter, owing to a production error, the penultimate version of the PDF was published. The HTML version was always correct. The PDF has been corrected online.

Accuracy of the Diagnosis of Allergic Reactions in the Emergency Department

BACKGROUND AND OBJECTIVE

Suspicion of an acute allergic reaction is a common reason for attending the emergency department (ED). However, there are few comparisons between the initial diagnosis of suspected allergic reaction made in the ED with the definitive diagnosis made subsequently in the allergy department (AD). Objective: To compare details of the initial diagnosis made in the ED relating to allergy with the final diagnosis made in the AD.

METHODS

Patients attending the ED of 2 hospitals with suspected allergic reactions were prospectively enrolled based on key words. A certified allergy specialist reviewed the ED records of these patients and, if these were suggestive of an allergic reaction, the patients were scheduled for further evaluation at the allergy clinic.

RESULTS

In total, 2000 patients were enrolled between April 2013 and October 2015. Of these, 1333 passed the initial assessment and underwent further evaluation. Of the 1333 patients, 528 underwent an allergological study, and 206 were confirmed as being allergic. With respect to drug allergy, nonsteroidal anti-inflammatory drugs were the most common triggers, followed by β-lactams; in food allergy, plant-based foods were the most common. Only 16.4% of patients confirmed as having anaphylaxis in the AD were initially diagnosed with the condition in the ED.

CONCLUSION

Of the 528 patients who finally underwent the full allergological study, fewer than half were confirmed as allergic. Moreover, anaphylaxis appears to be underdiagnosed in the ED. Better communication between the ED and the AD is necessary to improve the diagnosis and management of these patients.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

An EAACI task force report: recognising the potential of the primary care physician in the diagnosis and management of drug hypersensitivity

Adverse drug reactions include drug hypersensitivity reactions (DHRs), which can be immunologically mediated (allergy) or non-immunologically mediated. The high number of DHRs that are unconfirmed and often self-reported is a frequent problem in daily clinical practice, with considerable impact on future prescription choices and patient health. It is important to distinguish between hypersensitivity and non-hypersensitivity reactions by adopting a structured diagnostic approach to confirm or discard the suspected drug, not only to avoid life-threatening reactions, but also to reduce the frequent over-diagnosis of DHRs. Primary care physicians are often the first point of contact for the sufferer of a reaction, as such they have a key role in deciding whether to discard the diagnosis or send the patient for further investigation. In this review, we highlight the importance of diagnosing DHRs, analysing in detail the role of primary care physicians. We describe the common patterns of DHRs and signs of its progression, as well as the indications and contraindications for referring the patient to an allergist. The diagnostic process is described and the possible tests are discussed, which often depend on the drug involved and the type of DHR suspected. We also describe recommendations regarding the avoidance of medication suspected to have caused the reaction and the use of alternatives.

Extended gamma-ray sources around pulsars constrain the origin of the positron flux at Earth

The unexpectedly high flux of cosmic-ray positrons detected at Earth may originate from nearby astrophysical sources, dark matter, or unknown processes of cosmic-ray secondary production. We report the detection, using the High-Altitude Water Cherenkov Observatory (HAWC), of extended tera-electron volt gamma-ray emission coincident with the locations of two nearby middle-aged pulsars (Geminga and PSR B0656+14). The HAWC observations demonstrate that these pulsars are indeed local sources of accelerated leptons, but the measured tera-electron volt emission profile constrains the diffusion of particles away from these sources to be much slower than previously assumed. We demonstrate that the leptons emitted by these objects are therefore unlikely to be the origin of the excess positrons, which may have a more exotic origin.

Using radio astronomical receivers for molecular spectroscopic characterization in astrochemical laboratory simulations: A proof of concept

We present a proof of concept on the coupling of radio astronomical receivers and spectrometers with chemical reactors and the performances of the resulting setup for spectroscopy and chemical simulations in laboratory astrophysics. Several experiments including cold plasma generation and UV photochemistry were performed in a 40 cm long gas cell placed in the beam path of the Aries 40 m radio telescope receivers operating in the 41-49 GHz frequency range interfaced with fast Fourier transform spectrometers providing 2 GHz bandwidth and 38 kHz resolution. The impedance matching of the cell windows has been studied using different materials. The choice of the material and its thickness was critical to obtain a sensitivity identical to that of standard radio astronomical observations. Spectroscopic signals arising from very low partial pressures of CH₃OH, CH₃CH₂OH, HCOOH, OCS, CS, SO₂ (<10^-3 mbar) were detected in a few seconds. Fast data acquisition was achieved allowing for kinetic measurements in fragmentation experiments using electron impact or UV irradiation. Time evolution of chemical reactions involving OCS, O₂ and CS₂ was also observed demonstrating that reactive species, such as CS, can be maintained with high abundance in the gas phase during these experiments.

The anti-CD6 antibody itolizumab provides clinical benefit without lymphopenia in rheumatoid arthritis patients: results from a 6-month, open-label Phase I clinical trial

Itolizumab is a humanized anti-CD6 monoclonal antibody (mAb) that has previously shown encouraging results, in terms of safety and positive clinical effects, in a 6-week monotherapy clinical trial conducted in rheumatoid arthritis (RA) patients. The current Phase I study evaluated the safety and clinical response for a longer treatment of 12 itolizumab intravenous doses in subjects with active RA despite previous disease-modifying anti-rheumatic drug (DMARD) therapy. Twenty-one subjects were enrolled into four dosage groups (0·1, 0·2, 0·4 and 0·8 mg/kg). Efficacy end-points including American College of Rheumatology (ACR)20, ACR50 and ACR70 response rates and disease activity score in 28 joints (DAS28) were monitored at baseline and at specific time-points during a 10-week follow-up period. Itolizumab was well tolerated up to the highest tested dose. No related serious adverse events were reported and most adverse events were mild. Remarkably, itolizumab treatment did not produce lymphopenia and, therefore, was not associated with infections. All patients achieved a clinical response (ACR20) at least once during the study. Eleven subjects (55%) achieved at least a 20% improvement in ACR just 1 week after the first itolizumab administration. The clinical response was observed from the beginning of the treatment and was sustained during 24 weeks. The efficacy profile of this 12-week treatment was similar to that of the previous study (6-week treatment). These results reinforce the safety profile of itolizumab and provide further evidence on the clinical benefit from the use of this anti-CD6 mAb in RA patients.

Discovery of methyl silane and confirmation of silyl cyanide in IRC +10216

We report the discovery in space of methyl silane, CH3SiH3, from observations of ten rotational transitions between 80 and 350 GHz (Ju from 4 to 16) with the IRAM 30 m radio telescope. The molecule was observed in the envelope of the C-star IRC +10216. The observed profiles and our models for the expected emission of methyl silane suggest that the it is formed in the inner zones of the circumstellar envelope, 1-40 R*, with an abundance of (0.5-1) × 10-8 relative to H2. We also observed several rotational transitions of silyl cyanide (SiH3CN), confirming its presence in IRC +10216 in particular, and in space in general. Our models indicate that silyl cyanide is also formed in the inner regions of the envelope, around 20 R*, with an abundance relative to H2 of 6×10-10. The possible formation mechanisms of both species are discussed. We also searched for related chemical species but only upper limits could be obtained.

CB1-5-HT2A heteromers in schizophrenia patients: Human studies in pro-neurons of the olfactory epithelium

Introduction

Despite multiple clinical and preclinical studies investigating schizophrenia, the neurobiological basis of this disease is still unknown. The dysregulation of the serotonergic system, in particular the 5-HT2A receptor and the endocannabinoid system have been postulated as possible causes of schizophrenia.

Objectives

The aim of this study is to evaluate the expression of CB1-5-HT2A receptor heteromers in primary cultures of pro-neurons from the olfactory epithelium in schizophrenia patients and control subjects.

Methods

We recruited a group of 10 healthy volunteers and 10 patients diagnosed with schizophrenia, who were treated with atypical antipsychotics, were clinically stable and had an illness duration range from 1 up to 15 years. The patients were diagnosed with schizophrenia from the medical record and confirmed by the structured clinical interview for DSM disorders. The expression of CB1-5-HT2A receptor heteromers in primary cultures of pro-neurons from the olfactory epithelium was quantified using proximity ligation assays and confocal microscopy.

Results

Olfactory epithelium pro-neurons were viable and expressed the neuronal marker, III-β tubulin. We also established the presence and the functionality of CB1-5-HT2A receptor heteromers in these cells using the proximity ligation and cAMP activity assays, respectively. Heteromer expression was significantly increased in schizophrenia patients with respect to controls.

Conclusions

This highly innovative methodology will allow the noninvasive, low-cost study of new biomarkers for schizophrenia in a model closely related to the central nervous system.

Disclosure of interest

The authors have not supplied their declaration of competing interest.Acknowledgments

This work was supported by grants from DIUE-Generalitat-de Catalunya (2014SGR 680), Instituto de Salud Carlos III (PI14/00210) and (PI10/01708) FIS-FEDER-Funds. LG is supported by the Instituto-de Salud Carlos III through a “Río Hortega” (CM14/00111).