Transcriptional frameshifts contribute to protein allergenicity

Transcription infidelity (TI) is a mechanism that increases RNA and protein diversity. We found that single-base omissions (i.e., gaps) occurred at significantly higher rates in the RNA of highly allergenic legumes. Transcripts from peanut, soybean, sesame, and mite allergens contained a higher density of gaps than those of nonallergens. Allergen transcripts translate into proteins with a cationic carboxy terminus depleted in hydrophobic residues. In mice, recombinant TI variants of the peanut allergen Ara h 2, but not the canonical allergen itself, induced, without adjuvant, the production of anaphylactogenic specific IgE (sIgE), binding to linear epitopes on both canonical and TI segments of the TI variants. The removal of cationic proteins from bovine lactoserum markedly reduced its capacity to induce sIgE. In peanut-allergic children, the sIgE reactivity was directed toward both canonical and TI segments of Ara h 2 variants. We discovered 2 peanut allergens, which we believe to be previously unreported, because of their RNA-DNA divergence gap patterns and TI peptide amino acid composition. Finally, we showed that the sIgE of children with IgE-negative milk allergy targeted cationic proteins in lactoserum. We propose that it is not the canonical allergens, but their TI variants, that initiate sIgE isotype switching, while both canonical and TI variants elicit clinical allergic reactions.

Bovine scavenger receptor class A (SR-A) exhibit specific patterns of regulation in the endometrium during the oestrous cycle and early pregnancy

In mammals, tight regulation of maternal endometrial function is critical for pregnancy success. In bovine species, endometrial expression of members of the scavenger receptor class A (SR-A) has been listed in high-throughput analyses, but very little is known about the involvement of these immune factors during implantation in mammals. To provide first insights into the contribution of SR-A to endometrial physiology, we analysed the expression and regulation of all members of SR-A (SR-A1, SR-A3-SR-A6) during the oestrous cycle and early pregnancy in cattle. Levels of SR-A1 were increased on Day 20 of pregnancy, whereas SR-A3 levels were increased on Day 13 of the oestrous cycle and of the pregnancy. Although SR-A4 levels were reduced on Day 20 of the oestrous cycle, they remained high in pregnant animals. SR-A5 levels increased by Day 13 of the oestrous cycle and decreased on Day 20, but remained high in pregnant animals. Interferon-τ does not affect SR-A gene expression, whereas progesterone regulates the expression of the SR-A3 and SR-A5 transcripts. Endometrial SR-A3 appeared significantly higher in cows carrying invitro-produced embryos than in AI cows. Our data suggest that members of the SR-A family are involved in endometrial remodelling and regulation of endometrial gland physiology, both processes being critical for implantation in mammals.

Educational content and challenges encountered when training service user representatives as peer researchers in a mixed study on patient experience of hospital safety

BACKGROUND AND OBJECTIVES

In France, following the passing of a 2002 law, service user representatives (SURs) are part of hospital committees in charge of care quality and safety issues. Ten service user representatives (SURs) were recruited and trained as "peer researchers" to participate in all phases of a study aimed at outlining how patients experience hospital safety. This article aims to describe the study protocol and how peer researchers training was designed and implemented to prepare them to drive a qualitative and quantitative research. It also examines the challenges related to collaborative research and how these were resolved.

METHODS

The way our training was conceived belongs to the field of "design-based research", known for its pragmatic and collaborative scope, in which viewpoints of all participants are included. Our training was therefore based on peer researchers and research sponsors expectations, as well as on recommendations of the literature.

RESULTS

A 45-h training was held. While the program was meant to train peer researchers to respect scientific norms, it also aimed to improve their sense of self-legitimacy as they navigated their new role. Peer researchers were particularly eager to understand meaning behind the instructions, especially in the field of ethical and scientific norms. Various challenges occurred related to project organization, recruitment and peer researchers involvement. Some issues were overcome by learning how to share control over the research process.

CONCLUSION

This experiment highlights the importance of a training program's duration and quality to prepare SURs for their roles as peer investigators and to create a group dynamic around a research project, even with SURs familiar with patient involvement and our research theme (safety issues). Trainers overcame hurdles by being adaptive and by using educational approaches. They also learned to include trainees' input, even when it forced them to reconsider their own assumptions.

Measurements of a 2.1 MeV H- beam with an Allison scanner

Transverse 2D phase space distributions of a 2.1 MeV, 5 mA H^- beam are measured at the Proton Improvement Plan II Injector Test accelerator at Fermilab with an Allison scanner. This paper describes the design, calibration, and performance of the scanner along with the main results from beam measurements. Analyses of the recorded phase portraits are performed primarily in action-phase coordinates. The stability of the action under linear optics makes it easier to compare measurements taken under different beamline conditions. The amplitude of a single measured point ("pixel") is proportional to the phase density in the corresponding portion of the beam. When the Twiss parameters are calculated using only the high-phase density part of the beam, the pixel amplitude in the beam core is found to be decreasing approximately exponentially with action and to be phase-independent. Outside of the core, the amplitudes decrease with action at a slower rate than in the core. This "tail" comprises 10%-30% of the beam, with 0.1% of the total measured intensity extending beyond action 10-20 times larger than the rms emittance. The transition from the core to the tail is accompanied by the appearance of two "branches" that are separated in phase and extend beyond the core. A set of selected measurements shows that there is no measurable emittance dilution along the beamline; the beam parameters are practically constant over a 0.5 ms pulse; and scraping in various parts of the beamline is an effective way to decrease the transverse tails by removing the branches.

Evaluation of a program of pharmaceutical counseling for French patients on oral anticoagulant therapy

Background Oral anticoagulants are widely used for treatment and prevention of thromboembolic diseases. We set up a pharmaceutical counseling program for both direct oral anticoagulant and vitamin K antagonist drugs in our hospital in 2015. Objective Evaluate patient satisfaction and the evolution of their knowledge throughout the pharmaceutical counseling program on anticoagulants and identify knowledge variability factors. Setting Cardiology Inpatient Unit from the University Antoine Béclère Hospital, France. Methods Evaluation was based on data collection of patients surveyed between 2015 and 2018. Inpatients in the cardiology department on oral anticoagulants were eligible. The learning process was designed to enhance patient knowledge and understanding based on 10 cognitive or self-management skills, relating to the optimization of oral anticoagulant therapy management. It consisted in 2 face-to-face interviews during hospitalization and 2 additional phone interviews one and six months after discharge. The median patient score was evaluated at each step of the process as well as the mean score for each item from the global population. A sub-analysis was run on the less well-acquired skills in order to identify risk factors for limited knowledge. The association between those factors and the level of knowledge (score ≥ 7 or < 7) was assessed using Chi square test followed by multivariate analysis. Main outcome measure Patient knowledge of anticoagulation therapy depending on specific factors. Results Of the 880 patients eligible for pharmaceutical counseling, 319 entered the process and 102 completed it. Median knowledge scores were 8/10 and 9/10 after the first and the final interviews respectively with a significant improvement (p = 0.0003). The least well-acquired items at each step were surveillance and under-dosing management. The sub-analysis showed the use of vitamin K antagonist to be linked to an enhanced understanding related to treatment surveillance (p = 0.029). Patients suffering from atrial fibrillation were found to have a worse understanding of under-dosing management (p = 0.013). Finally, patients evaluated the process as helpful and suitable for their conditions. Conclusion Pharmaceutical counseling is appropriate for patients, improving and maintaining knowledge of oral anticoagulants. Our evaluation highlights the need to focus on patient-specific profiles to reach a satisfactory level of knowledge.

115 Invivo confocal laser endomicroscopy visualisation of fresh and frozen bull spermatozoa in the genital tract of dairy heifers

Fertility in cattle includes the ability of the uterus to provide the appropriate environment for pregnancy success, including the transport of spermatozoa before fertilization. Confocal laser endomicroscopy technology (Cellvizio) has been previously used in small ruminants to visualise labelled spermatozoa invivo in the uterine horns of ewes (Druart et al. 2009 Reprod. 138, 15-53). Nevertheless, to the best of our knowledge, no invivo study has reported a live visual analysis of the behaviour of spermatozoa in the bovine uterus upon AI. The aim of this study was to develop an experimental procedure to label bull spermatozoa and to visualise their progression in the uterine horns of dairy cows, using Cellvizio and uterine cervix catheterization. Fresh ejaculated bull spermatozoa were double-labelled with octadecyl rhodamine B chloride and MitoTracker Green FM dyes before dilution and freezing processing. At each step of the process, semen quality was evaluated with a semen quality analyzer (SQA-V b, Medical Electronic System) and compared to nonlabelled bull reference semen. The specificity of the labelling was validated invitro. We also developed a specific device to insert the Cellvizio fibre probe into the genital tract, in order to image vagina, cervix, and uterine body, as well as the proximal, middle, and distal parts of the uterine horn, including the utero-tubal junction (UTJ), before and after AI with fresh and frozen labelled spermatozoa. Then, 10 heifers were oestrus synchronized. Video sequences were recorded at oestrus (n=5), just before AI, at the time of AI (7-12h after the onset of oestrus), 30 and 120min after AI, and 14 days after oestrus (n=5; luteal phase), to investigate the effect of the steroid-primed uterine environment on the distribution and progression of spermatozoa in the genital tract. Using our approach, labelled spermatozoa were detected (1) at the day of oestrus and 14 days after oestrus, (2) in the uterine body at the time of AI, (3) in various parts of the genital tract 30min after AI, and (4) in the UTJ, the cervix, and the vagina 120min after AI. In addition, labelling the spermatozoa did not alter the fertilizing capacity: 4 of the 5 oestrus females were pregnant at Day 35. Additionally, an IVF test showed a blastocyst rate of 45.8% for labelled semen vs. 39.4% for the control group (Carvalho et al. 2017 Reprod. 154, 695-710). In conclusion, our study provides a method to phenotype in situ the transport of spermatozoa in the genital tract of heifers. Further investigations are in progress to optimize video quality, to develop an algorithm for an automatic analysis (spermatozoa count, speed, and path) of the recorded sequences.

End-user perspectives to inform policy and program decisions: a qualitative and quantitative content analysis of lifestyle treatment recommendations by adolescents with obesity

Background

Lifestyle modifications represent the first line of treatment in obesity management; however, many adolescents with obesity do not meet lifestyle recommendations. Given that adolescents are rarely consulted during health policy development and in the design of lifestyle interventions, their first-hand experiences, preferences, and priorities may not be represented. Accordingly, our purpose was to explore adolescents’ lifestyle treatment recommendations to inform policy and program decisions.

Methods

Conducted from July 2017 to January 2018, this study adhered to a qualitative, crosslanguage, patient-oriented design. We recruited 19 13–17-year-old adolescents (body mass index [BMI] ≥85th percentile) seeking multidisciplinary treatment for obesity in geographically and culturally diverse regions of Canada. Adolescents participated in one-on-one, in-person, semi-structured interviews in English or French. Interviews were audio-recorded, transcribed verbatim, managed using NVivo 11, and analyzed using quantitative and qualitative content analysis by two independent researchers.

Results

Adolescents’ recommendations were organized into five categories, each of which denotes health as a collective responsibility: (i) establish parental support within limits, (ii) improve accessibility and availability of ‘healthy foods’, (iii) limit deceptive practices in food marketing, (iv) improve accessibility and availability of varied physical activity opportunities, and (v) delay school start times. Respect for individual autonomy and decision-making capacity were identified as particularly important, however these were confronted with adolescents’ partial knowledge on nutrition and food literacy.

Conclusions

Adolescents’ recommendations highlighted multi-level, multi-component factors that influenced their ability to lead healthy lifestyles. Uptake of these recommendations by policy-makers and program developers may be of added value for lifestyle treatment targeting adolescents with obesity.

Extracorporeal cardiopulmonary resuscitation in out-of-hospital cardiac arrest: a registry study

Aims

Out-of-hospital cardiac arrest (OHCA) without return of spontaneous circulation (ROSC) despite conventional resuscitation is common and has poor outcomes. Adding extracorporeal membrane oxygenation (ECMO) to cardiopulmonary resuscitation (extracorporeal-CPR) is increasingly used in an attempt to improve outcomes.

Methods and results

We analysed a prospective registry of 13 191 OHCAs in the Paris region from May 2011 to January 2018. We compared survival at hospital discharge with and without extracorporeal-CPR and identified factors associated with survival in patients given extracorporeal-CPR. Survival was 8% in 525 patients given extracorporeal-CPR and 9% in 12 666 patients given conventional-CPR (P = 0.91). By adjusted multivariate analysis, extracorporeal-CPR was not associated with hospital survival [odds ratio (OR), 1.3; 95% confidence interval (95% CI), 0.8–2.1; P = 0.24]. By conditional logistic regression with matching on a propensity score (including age, sex, occurrence at home, bystander CPR, initial rhythm, collapse-to-CPR time, duration of resuscitation, and ROSC), similar results were found (OR, 0.8; 95% CI, 0.5–1.3; P = 0.41). In the extracorporeal-CPR group, factors associated with hospital survival were initial shockable rhythm (OR, 3.9; 95% CI, 1.5–10.3; P = 0.005), transient ROSC before ECMO (OR, 2.3; 95% CI, 1.1–4.7; P = 0.03), and prehospital ECMO implantation (OR, 2.9; 95% CI, 1.5–5.9; P = 0.002).

Conclusions

In a population-based registry, 4% of OHCAs were treated with extracorporeal-CPR, which was not associated with increased hospital survival. Early ECMO implantation may improve outcomes. The initial rhythm and ROSC may help select patients for extracorporeal-CPR.

A 2-year multicenter, observational, prospective, cohort study on extracorporeal CO2 removal in a large metropolis area

Background

Extracorporeal carbon dioxide removal (ECCO₂R) is a promising technique for the management of acute respiratory failure, but with a limited level of evidence to support its use outside clinical trials and/or data collection initiatives. We report a collaborative initiative in a large metropolis.

Methods

To assess on a structural basis the rate of utilization as well as efficacy and safety parameters of 2 ECCO₂R devices in 10 intensive care units (ICU) during a 2-year period.

Results

Seventy patients were recruited in 10 voluntary and specifically trained centers. The median utilization rate was 0.19 patient/month/center (min 0.04; max 1.20). ECCO₂R was started under invasive mechanical ventilation (IMV) in 59 patients and non-invasive ventilation in 11 patients. The Hemolung Respiratory Assist System (Alung) was used in 53 patients and the iLA Activve iLA kit (Xenios Novalung) in 17 patients. Main indications were ultraprotective ventilation for ARDS patients (n = 24), shortening the duration of IMV in COPD patients (n = 21), preventing intubation in COPD patients (n = 9), and controlling hypercapnia and dynamic hyperinflation in mechanically ventilated patients with severe acute asthma (n = 6). A reduction in median V_T was observed in ARDS patients from 5.9 to 4.1 ml/kg (p <0.001). A reduction in PaCO₂ values was observed in AE-COPD patients from 67.5 to 51 mmHg (p< 0.001). Median duration of ECCO₂R was 5 days (IQR 3–8). Reasons for ECCO₂R discontinuation were improvement (n = 33), ECCO₂R-related complications (n = 18), limitation of life-sustaining therapies or measures decision (n = 10), and death (n = 9). Main adverse events were hemolysis (n = 21), bleeding (n = 17), and lung membrane clotting (n = 11), with different profiles between the devices. Thirty-five deaths occurred during the ICU stay, 3 of which being ECCO₂R-related.

Conclusions

Based on a registry, we report a low rate of ECCO₂R device utilization, mainly in severe COPD and ARDS patients. Physiological efficacy was confirmed in these two populations. We confirmed safety concerns such as hemolysis, bleeding, and thrombosis, with different profiles between the devices. Such results could help to design future studies aiming to enhance safety, to demonstrate a still-lacking strong clinical benefit of ECCO₂R, and to guide the choice between different devices.

Trial registration

ClinicalTrials.gov: Identifier: NCT02965079 retrospectively registered https://clinicaltrials.gov/ct2/show/NCT02965079

Single and multiple gene knockouts by CRISPR-Cas9 in maize

The analysis of 93 mutant alleles in 18 genes demonstrated that CRISPR-Cas9 is a robust tool for targeted mutagenesis in maize, permitting efficient generation of single and multiple knockouts. CRISPR-Cas9 technology is a simple and efficient tool for targeted mutagenesis of the genome. It has been implemented in many plant species, including crops such as maize. Here we report single- and multiple-gene mutagenesis via stably transformed maize plants. Two different CRISPR-Cas9 vectors were used allowing the expression of multiple guide RNAs and different strategies to knockout either independent or paralogous genes. A total of 12 plasmids, representing 28 different single guide RNAs (sgRNAs), were generated to target 20 genes. For 18 of these genes, at least one mutant allele was obtained, while two genes were recalcitrant to sequence editing. 19% (16/83) of mutant plants showed biallelic mutations. Small insertions or deletions of less than ten nucleotides were most frequently observed, regardless of whether the gene was targeted by one or more sgRNAs. Deletions of defined regions located between the target sites of two guide RNAs were also reported although the exact deletion size was variable. Double and triple mutants were created in a single step, which is especially valuable for functional analysis of genes with strong genetic linkage. Off-target effects were theoretically limited due to rigorous sgRNA design and random experimental checks at three potential off-target sites did not reveal any editing. Sanger chromatograms allowed to unambiguously class the primary transformants; the majority (85%) were fully edited plants transmitting systematically all detected mutations to the next generation, generally following Mendelian segregation.

Risk factors for treatment failure in scabies: a cohort study

BACKGROUND

Treatment failure, which occurs in about one-third of cases, is considered as a major factor in the increasing incidence of scabies in developed countries.

OBJECTIVES

To identify predictors of treatment failure of scabies in ambulatory populations.

METHODS

This multicentre study compared the clinical characteristics and treatment modalities between a group of patients with scabies treated successfully and another group who were not cured 3 months after antiscabies treatment.

RESULTS

In total 210 patients with a diagnosis of scabies were included, comprising 98 patients in the treatment success group and 112 in the treatment failure group. The main risk factors for treatment failure were (i) the use of only one type of treatment, topical benzyl benzoate (BB) or oral ivermectin, vs. the combination of both treatments [odds ratio (OR) 2·15, 95% confidence interval (CI) 1·22-3·77]; (ii) the use of a single intake (vs. two) of oral ivermectin (OR 10·2. 95% CI 4·49-23·2); (iii) intake of ivermectin during a meal vs. on an empty stomach (OR 4·31, 95% CI 1·89-9·84); (iv) absence of decontamination of furnishings (OR 8·72, 95% CI 3·50-21·8), in particular sofa and cushions (OR 5·90, 95% CI 2·34-14·9), mattresses (OR 4·16, 95% CI 1·35-12·8) or car seats (OR 6·57, 95% CI 3·27-13·2) and (v) absence of written documents explaining treatment modalities (OR 5·18, 95% CI 2·57-10·4). In multivariate analysis, treatment failure was mainly associated with (i) use of a single intake (vs. two) of ivermectin (OR 6·62, 95% CI 2·71-16·2); (ii) use of BB alone vs. two intakes of ivermectin (OR 3·51, 95% CI 1·55-7·95) and (iii) absence of decontamination of furniture with acaricides (OR 5·81, 95% CI 1·96-16·7).

CONCLUSIONS

Use of topical BB alone and a single intake (vs. two) of ivermectin are predictors of treatment failure.