A ratiometric fluorescence probe for bisulfite detection in live cells and meat samples

The development of reliable probe technology for the detection of bisulfite (HSO3-) in situ in food and biological samples is contributing significantly to food quality and safety assurance as well as community health. In this work, a responsive probe, EHDI, is developed for ratiometric fluorescence detection of HSO3- in aqueous solution, meat samples, and living cells. The probe is designed based on the HSO3- triggered 1,4-addition of electron deficit C = C bond of EHDI. As a result of this specific 1,4-addition, the π-conjugation system was destructed, resulting in blue shifts of the emission from 687 to 440 nm and absorption from 577 to 355 nm. The probe has good water solubility, high sensitivity and selectivity, allowing it to be used for imaging of HSO3- internalization and production endogenously. The capability of probe EHDI for HSO3- was then validated by traditional HPLC technology, enabling accurately detect HSO3- in beef samples. The successful development of this probe thus offers a new tool for investigating HSO3- in situ in food and biological conditions.

Understanding the effect of moderate concentration SDS on CO2 hydrates growth in the presence of THF

Hypothesis Additives like Tetrahydrofuran (THF) and Sodium Dodecylsulfate (SDS) improve Carbon Dioxide (CO2) hydrates thermal stability and growth rate when used separately. It has been hypothesised that combining them could improve the kinetics of growth and the thermodynamic stability of CO2 hydrates. Simulations and Experiments We exploit atomistic molecular dynamics simulations to investigate the combined impact of THF and SDS under different temperatures and concentrations. The simulation insights are verified experimentally using pendant drop tensiometry conducted at ambient pressures and high-pressure differential scanning calorimetry. Findings Our simulations revealed that the combination of both additives is synergistic at low temperatures but antagonistic at temperatures above 274.1 K due to the aggregation of SDS molecules induced by THF molecules. These aggregates effectively remove THF and CO2 from the hydrate-liquid interface, thereby reducing the driving force for hydrates growth. Experiments revealed that the critical micelle concentration of SDS in water decreases by 20% upon the addition of THF. Further experiments in the presence of THF showed that only small amounts of SDS are sufficient to increase the CO2 storage efficiency by over 40% compared to results obtained without promoters. Overall, our results provide microscopic insights into the mechanisms of THF and SDS promoters on CO2 hydrates, useful for determining the optimal conditions for hydrate growth.

Extracellular Vesicle-Encapsulated Adeno-Associated Viruses for Therapeutic Gene Delivery to the Heart

BACKGROUND

Adeno-associated virus (AAV) has emerged as one of the best tools for cardiac gene delivery due to its cardiotropism, long-term expression, and safety. However, a significant challenge to its successful clinical use is preexisting neutralizing antibodies (NAbs), which bind to free AAVs, prevent efficient gene transduction, and reduce or negate therapeutic effects. Here we describe extracellular vesicle-encapsulated AAVs (EV-AAVs), secreted naturally by AAV-producing cells, as a superior cardiac gene delivery vector that delivers more genes and offers higher NAb resistance.

METHODS

We developed a 2-step density-gradient ultracentrifugation method to isolate highly purified EV-AAVs. We compared the gene delivery and therapeutic efficacy of EV-AAVs with an equal titer of free AAVs in the presence of NAbs, both in vitro and in vivo. In addition, we investigated the mechanism of EV-AAV uptake in human left ventricular and human induced pluripotent stem cell-derived cardiomyocytes in vitro and mouse models in vivo using a combination of biochemical techniques, flow cytometry, and immunofluorescence imaging.

RESULTS

Using cardiotropic AAV serotypes 6 and 9 and several reporter constructs, we demonstrated that EV-AAVs deliver significantly higher quantities of genes than AAVs in the presence of NAbs, both to human left ventricular and human induced pluripotent stem cell-derived cardiomyocytes in vitro and to mouse hearts in vivo. Intramyocardial delivery of EV-AAV9-sarcoplasmic reticulum calcium ATPase 2a to infarcted hearts in preimmunized mice significantly improved ejection fraction and fractional shortening compared with AAV9-sarcoplasmic reticulum calcium ATPase 2a delivery. These data validated NAb evasion by and therapeutic efficacy of EV-AAV9 vectors. Trafficking studies using human induced pluripotent stem cell-derived cells in vitro and mouse hearts in vivo showed significantly higher expression of EV-AAV6/9-delivered genes in cardiomyocytes compared with noncardiomyocytes, even with comparable cellular uptake. Using cellular subfraction analyses and pH-sensitive dyes, we discovered that EV-AAVs were internalized into acidic endosomal compartments of cardiomyocytes for releasing and acidifying AAVs for their nuclear uptake.

CONCLUSIONS

Together, using 5 different in vitro and in vivo model systems, we demonstrate significantly higher potency and therapeutic efficacy of EV-AAV vectors compared with free AAVs in the presence of NAbs. These results establish the potential of EV-AAV vectors as a gene delivery tool to treat heart failure.

Multi-session transcutaneous auricular vagus nerve stimulation for Parkinson's disease: evaluating feasibility, safety, and preliminary efficacy

BACKGROUND

In pre-clinical animal models of Parkinson's disease (PD), vagus nerve stimulation (VNS) can rescue motor deficits and protect susceptible neuronal populations. Transcutaneous auricular vagus nerve stimulation (taVNS) has emerged as a non-invasive alternative to traditional invasive cervical VNS. This is the first report summarizing the safety, feasibility, and preliminary efficacy of repeated sessions of taVNS in participants with PD.

OBJECTIVES

To evaluate the feasibility, safety, and possible efficacy of taVNS for motor and non-motor symptoms in mild to moderate PD.

METHODS

This is a double-blind, sham controlled RCT (NCT04157621) of taVNS in 30 subjects with mild to moderate PD without cognitive impairment. Participants received 10, 1-h taVNS sessions (25 Hz, 200% of sensory threshold, 500 μs pulse width, 60 s on and 30 s off) over a 2-week period. Primary outcome measures were feasibility and safety of the intervention; secondary outcomes included the MDS-UPDRS, cognitive function and self-reported symptom improvement.

RESULTS

taVNS treatment was feasible, however, daily in-office visits were reported as being burdensome for participants. While five participants in the taVNS group and three in the sham group self-reported one or more minor adverse events, no major adverse events occurred. There were no group differences on blood pressure and heart rate throughout the intervention. There were no group differences in MDS-UPDRS scores or self-reported measures. Although global cognitive scores remained stable across groups, there was a reduction in verbal fluency within the taVNS group.

CONCLUSIONS

taVNS was safe, and well-tolerated in PD participants. Future studies of taVNS for PD should explore at-home stimulation devices and optimize stimulation parameters to reduce variability and maximize engagement of neural targets.

Microscopic insights on clathrate hydrate growth from non-equilibrium molecular dynamics simulations

Clathrate hydrates form and grow at interfaces. Understanding the relevant molecular processes is crucial for developing hydrate-based technologies. Many computational studies focus on hydrate growth within the aqueous phase using the 'direct coexistence method', which is limited in its ability to investigate hydrate film growth at hydrocarbon-water interfaces. To overcome this shortcoming, a new simulation setup is presented here, which allows us to study the growth of a methane hydrate nucleus in a system where oil-water, hydrate-water, and hydrate-oil interfaces are all simultaneously present, thereby mimicking experimental setups. Using this setup, hydrate growth is studied here under the influence of two additives, a polyvinylcaprolactam oligomer and sodium dodecyl sulfate, at varying concentrations. Our results confirm that hydrate films grow along the oil-water interface, in general agreement with visual experimental observations; growth, albeit slower, also occurs at the hydrate-water interface, the interface most often interrogated via simulations. The results obtained demonstrate that the additives present within curved interfaces control the solubility of methane in the aqueous phase, which correlates with hydrate growth rate. Building on our simulation insights, we suggest that by combining data for the potential of mean force profile for methane transport across the oil-water interface and for the average free energy required to perturb a flat interface, it is possible to predict the performance of additives used to control hydrate growth. These insights could be helpful to achieve optimal methane storage in hydrates, one of many applications which are attracting significant fundamental and applied interests.

Stochastic Cellular Automata Modeling of CO2 Hydrate Growth and Morphology

Carbon dioxide (CO₂) hydrates are important in a diverse range of applications and technologies in the environmental and energy fields. The development of such technologies relies on fundamental understanding, which necessitates not only experimental but also computational studies of the growth behavior of CO₂ hydrates and the factors affecting their crystal morphology. As experimental observations show that the morphology of CO₂ hydrate particles differs depending on growth conditions, a detailed understanding of the relation between the hydrate structure and growth conditions would be helpful. To this end, this work adopts a modeling approach based on hybrid probabilistic cellular automata to investigate variations in CO₂ hydrate crystal morphology during hydrate growth from stagnant liquid water presaturated with CO₂. The model, which uses free energy density profiles as inputs, correlates the variations in growth morphology to the system subcooling ΔT, i.e., the temperature deficiency from the triple CO₂-hydrate-water equilibrium temperature under a given pressure, and properties of the growing hydrate-water interface, such as surface tension and curvature. The model predicts that when ΔT is large, parabolic needle-like or dendrite crystals emerge from planar fronts that deform and lose stability. In agreement with chemical diffusion-limited growth, the position of such planar fronts versus time follows a power law. In contrast, the tips of the emerging parabolic crystals steadily grow in proportion to time. The modeling framework is computationally fast and produces complex growth morphology phenomena under diffusion-controlled growth from simple, easy-to-implement rules, opening the way for employing it in multiscale modeling of gas hydrates.

Chemical Promoter Performance for CO2 Hydrate Growth: A Molecular Perspective

Carbon dioxide (CO₂) hydrates, which contain a relatively large amount of captured CO₂ (almost 30 wt % of CO₂ with the balance being water), represent a promising CO₂ sequestration option for climate change mitigation. To facilitate CO₂ storage via hydrates, using chemical additives during hydrate formation might help to expedite formation/growth rates, provided the additives do not reduce the storage capacity. Implementing atomistic molecular dynamics, we study the impact of aziridine, pyrrolidine, and tetrahydrofuran (THF) on the kinetics of CO₂ hydrate growth/dissociation. Our simulations are validated via reproducing experimental data for CO₂ and CO₂ + THF hydrates at selected operating conditions. The simulated results show that both aziridine and pyrrolidine could perform as competent thermodynamic and kinetic promoters. Furthermore, aziridine seems to exceed pyrrolidine and THF in expediting the CO₂ hydrate growth rates under the same conditions. Our analysis unveils direct correlations between the kinetics of CO₂ hydrate growth and a combination of the free energy barrier for desorption of CO₂ from the hydrate surface and the binding free energy of chemical additives adsorbed at the growing hydrate substrate. The detailed thermodynamic analysis conducted in both hydrate and aqueous phases reveals molecular-level mechanisms by which CO₂ hydrate promoters are active, which could help to enable the implementation of CO₂ sequestration in hydrate-bearing reservoirs.

Development of europium(III) complex functionalized silica nanoprobe for luminescence detection of tetracycline

Increasing awareness of the health and environment impacts of the antibiotics misuse or overuse, such as tetracycline (TC) in treatment or prevention of infections and diseases, has driven the development of robust methods for their detection in biological, environmental and food systems. In this work, we report the development of a new europium(III) complex functionalized silica nanoprobe (SiNPs-Eu³⁺) for highly sensitive and selective detection of TC residue in aqueous solution and food samples (milk and meat). The nanoprobe is developed by immobilization of Eu³⁺ ion onto the surface of silica nanoparticles (SiNPs) as the emitter and TC recognition unit. The β-diketone configuration of TC can further coordinate with Eu³⁺ steadily on the surface of nanoprobe, facilitating the absorption of light excitation for Eu³⁺ emitter activation and luminescence "off-on" response. The dose-dependent luminescence enhancement of SiNPs-Eu³⁺ nanoprobe exhibits good linearities, allowing the quantitative detection of TC. The SiNPs-Eu³⁺ nanoprobe shows high sensitivity and selectivity for TC detection in buffer solution. Time resolved luminescence analysis enables the elimination of autofluorescence and light scattering for highly sensitive detection of TC in milk and pork mince with high accuracy and precision. The successful development of SiNPs-Eu³⁺ nanoprobe is anticipated to provide a rapid, economic, and robust approach for TC detection in real world samples.

Wetting Properties of Clathrate Hydrates in the Presence of Polycyclic Aromatic Compounds: Evidence of Ion-Specific Effects

Polycyclic aromatic hydrocarbons (PAHs) have attracted remarkable multidisciplinary attention due to their intriguing π-π stacking configurations, showing enormous opportunity for their use in a variety of advanced applications. To secure progress, detailed knowledge on PAHs' interfacial properties is required. Employing molecular dynamics, we probe the wetting properties of brine droplets (KCl, NaCl, and CaCl₂) on sII methane-ethane hydrate surfaces immersed in various oil solvents. Our simulations show synergistic effects due to the presence of PAHs compounded by ion-specific effects. Our analysis reveals phenomenological correlations between the wetting properties and a combination of the binding free-energy difference and entropy changes upon oil solvation for PAHs at oil/brine and oil/hydrate interfaces. The detailed thermodynamic analysis conducted upon the interactions between PAHs and various interfaces identifies molecular-level mechanisms responsible for wettability alterations, which could be applicable for advancing applications in optics, microfluidics, biotechnology, medicine, as well as hydrate management.

Abstract P3097: Post-transcriptional Mechanisms Of FTO-regulated Cardiac Contractility

Background: N6-methyladenosine (m6A), the most abundant and functionally relevant mRNA modification, is reversibly demethylated by FTO, an m6A eraser and a primary regulator of m6A in the heart. In failing hearts, decreased FTO increases m6A, critically reducing cardiomyocyte contraction. FTO overexpression improved cardiac contraction and attenuated remodeling. Here, we investigate post-transcriptional and translational mechanisms of FTO-regulation of cardiomyocyte contraction in vitro and in vivo. We hypothesize that FTO directly binds to selective cardiac contractile mRNAs at their m6A site and affects their nuclear export, polysome binding, cytoplasmic availability, and protein expression.

Methods and Results: We performed immunostaining to examine the intracellular location and expression of FTO under different pathological stimuli in human ventricular cardiomyocyte cell line (AC16 cells), rat primary cardiomyocytes and mouse and human hearts. FTO was detected in both cytoplasmic and nuclear compartments, and was significantly reduced in pathological hearts compared to healthy controls. MeRIP (immunoprecipitation of m6A-RNA) sequencing analysis uncovered that FTO targets different sets of cardiac mRNAs in the cytoplasm and nucleus of cardiomyocytes. Knocking down FTO increased nuclear retention of cardiac mRNAs, which was reversed with FTO overexpression. Immunoprecipitation experiments demonstrated that FTO directly binds to cardiac mRNAs. To determine the effect of FTO on translation of select cardiac mRNAs, we isolated the polysome fraction from the cytoplasm of AC16 cells. Interestingly, our stable isotope labeling with amino acids in cell culture (SILAC) and mass spectrometry analyses suggested increased expression of cardiac contractile proteins with FTO overexpression.

Conclusion: We demonstrate that FTO positively regulates post-transcriptional nuclear export, polysome binding of cardiac contractile mRNAs, and regulates their translation under pathological stimuli. By combining experimental and predictive models in human and mice, we have characterized the transcriptome-proteome molecular interplay regulating cardiac function.

Dermatologic manifestations in paediatric neurofibromatosis type 2: a cross sectional descriptive multicentric study

Background

Neurofibromatosis type 2 (NF2) is characterized by bilateral vestibular schwannoma (VS) more often in adults but a severe paediatric form with multiple neurological tumours is also described. In this population, a early diagnosis is important to prevent the onset of neurological complications but is difficult, particularly without a familial history. Cutaneous manifestations, which may precede VS or neurological tumours by several years, may contribute to an early diagnosis, but specific studies are lacking. The objective of this study was to characterize cutaneous manifestations of NF2 in a paediatric population.

Results

This observational, descriptive and multicentric study was conducted from April 2019 to April 2020 in seven academic French hospitals. We included patients ≤ 18 years old who fulfilled the Manchester diagnostic criteria or had a pathogenic mutation identified in the NF2 gene. All patients underwent a dermatological examination guided by a standardized questionnaire. 21 children were included, of whom 20 had at least one skin tumour (mean number 5 ± 4.6 [range 0–15]), which led to a diagnosis in four cases. In the other 17 cases, the diagnosis of NF2 was based on neurosensory complications (n = 10), family screening (n = 4) or ocular signs (n = 3). Before the NF2 diagnosis, 15 children had at least one “undiagnosed” cutaneous tumour that did not lead to a specific management. Patients’ dermatological examination also revealed < 6 non specific café au lait macules (n = 15), hypopigmented macules (n = 12) with more than 3 lesions in 4 cases, and purple reticulated macules of the trunk (n = 4).

Conclusion

Dermatological lesions are frequent and early in children with NF2 but rarely lead to the diagnosis. Cutaneous schwannomas are the most frequent but are often underdiagnosed. Café au lait macules are frequent, but atypical and mostly in small numbers. Multiple hypopigmented macules seem suggestive although inconsistent. The sensitivity of reticulated capillary malformation-like lesions remains to be assessed by further studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02379-6.

Safety and efficacy of low-dose PI3K inhibitor taselisib in adult patients with CLOVES and Klippel-Trenaunay syndrome (KTS): the TOTEM trial, a phase 1/2 multicenter, open-label, single-arm study

PURPOSE

PIK3CA pathogenic variants in the PIK3CA-related overgrowth spectrum (PROS) activate phosphoinositide 3-kinase signaling, providing a rationale for targeted therapy, but no drug has proven efficacy and safety in this population. Our aim was to establish the six-month tolerability and efficacy of low-dose taselisib, a selective class I PI3K inhibitor, in PROS patients.

METHODS

Patients over 16 years with PROS and PIK3CA pathogenic variants were included in a phase IB/IIA multicenter, open-label single-arm trial (six patients at 1 mg/day of taselisib, then 24 at 2 mg/day). The primary outcome was the occurrence of dose limiting toxicity (DLT). Efficacy outcomes were the relative changes after treatment of (1) tissue volume at affected and unaffected sites, both clinically and on imaging; (2) cutaneous vascular outcomes when relevant; (3) biologic parameters; (4) quality of life; and (5) patient-reported outcomes.

RESULTS

Among 19 enrolled patients, 2 experienced a DLT (enteritis and pachymeningitis) leading to early trial termination (17 treated, 10 completed the study). No serious adverse reaction occurred in the 1 mg cohort (n = 6). No significant reduction in affected tissue volume was observed (mean -4.2%; p = 0.81; SD 14.01). Thirteen (76.4%) participants reported clinical improvement (pain reduction, chronic bleeding resolution, functional improvement).

CONCLUSION

Despite functional improvement, the safety profile of low-dose taselisib precludes its long-term use.

Water Wettability Coupled with Film Growth on Realistic Cyclopentane Hydrate Surfaces

Although the wettability of hydrate surfaces and hydrate film growth are key to understanding hydrate agglomeration and pipeline plugging, a quantitative understanding of the coupled behavior between both phenomena is lacking. In situ measurements of wettability coupled with film growth were performed for cyclopentane hydrate surfaces in cyclopentane at atmospheric pressure and temperatures between 1.5-6.8 °C. Results were obtained as a function of annealing (conversion) time and subcooling. Hydrate surface wettability decreased as annealing time increased, while hydrate film growth rate was unaffected by annealing time at any subcooling. The results are interpreted as a manifestation of the hydrate surface porosity, which depends on annealing time and controls water spreading on the hydrate surface. The wettability generally decreased as the subcooling increased because higher subcooling yields rougher hydrate surfaces, making it harder for water to spread. However, this effect is balanced by hydrate growth rates, which increase with subcooling. Also affecting the results, surface heating from heat release (from exothermic crystallization) allows excess surface water to promote spreading. The hydrate film growth rate on water droplets increased with subcooling, as expected from a higher driving force. At any subcooling, the instantaneous hydrate growth rate decreased over time, likely from heat transfer limitations. A new phenomenon was observed, where the angle at the three-phase point increases from the initial contact angle upon hydrate film growth, named the crystallization angle. This is attributed to the water droplet trying to spread while the thin film is weak enough to be redirected. Once the hydrate film grows and forms a "wall" around the droplet, it cannot be moved, and further growth yields a crater on the droplet surface, attributed to water penetrating the hydrate surface pore structures. This fundamental behavior has many flow assurance implications since it affects the interactions between the agglomerating hydrate particles and water droplets.

Reduced turnaround times through multi-sectoral community collaboration during the first surge of SARS-CoV-2 and associated effect on patient care and hospital operations

BACKGROUND

In March 2020, an influx of admissions in COVID-19 positive patients threatened to overwhelm healthcare facilities in East Baton Rouge Parish, Louisiana. Exacerbating this problem was an overall shortage of diagnostic testing capability at that time, resulting in a delay in time-to-result return. An improvement in diagnostic testing availability and timeliness was necessary to improve the allocation of resources and ultimate throughput of patients. The management of a COVID-19 positive patient or patient under investigation requires infection control measures that can quickly consume personal protective equipment (PPE) stores and personnel available to treat these patients. Critical shortages of both PPE and personnel also negatively impact care in patients admitted with non-COVID-19 illnesses.

METHODS

A multisectoral partnership of healthcare providers, facilities and academicians created a molecular diagnostic lab within an academic research facility dedicated to testing inpatients and healthcare personnel for SARS-CoV-2. The purpose of the laboratory was to provide a temporary solution to the East Baton Rouge Parish healthcare community until individual facilities were self-sustaining in testing capabilities. We describe the partnership and the impacts of this endeavor by developing a model derived from a combination of data sources, including electronic health records, hospital operations, and state and local resources.

FINDINGS

Our model demonstrates two important principles: the impact of reduced turnaround times (TAT) on potential differences in inpatient population numbers for COVID-19 and savings in PPE attributed to the more rapid TAT.

Correlating Antiagglomerant Performance with Gas Hydrate Cohesion

Although inhibiting hydrate formation in hydrocarbon-water systems is paramount in preventing pipe blockage in hydrocarbon transport systems, the molecular mechanisms responsible for antiagglomerant (AA) performance are not completely understood. To better understand why macroscopic performance is affected by apparently small changes in the AA molecular structure, we perform molecular dynamics simulations. We quantify the cohesion energy between two gas hydrate nanoparticles dispersed in liquid hydrocarbons in the presence of different AAs, and we achieve excellent agreement against experimental data obtained at high pressure using the micromechanical force apparatus. This suggests that the proposed simulation approach could provide a screening method for predicting, in silico, the performance of new molecules designed to manage hydrates in flow assurance. Our results suggest that entropy and free energy of solvation of AAs, combined in some cases with the molecular orientation at hydrate-oil interfaces, are descriptors that could be used to predict performance, should the results presented here be reproduced for other systems as well. These insights could help speed up the design of new AAs and guide future experiments.

Aqueous films on pore surfaces mediate adsorption and transport of gases through crowded nanopores

Interactions of trapped reservoir gases within organic-rich and brine-bearing sedimentary rocks have direct relevance to many geoenergy applications. Extracting generalizable information from experimental campaigns is hindered by the fact that geological systems are extremely complex. However, modern computational tools offer the opportunity of studying systems with controlled complexity, in an effort to better understand the mechanisms at play. Employing molecular dynamics, we examine here adsorption and transport of gases containing CH₄ and either CO₂ or H₂S within amorphous silica nanopores filled with benzene. We explicitly quantify the effect of small amounts of water/brines at geological temperature and pressure conditions. Because of wetting, the presence of brines lessens the adsorption capacity of the aromatic-filled pore. The simulation results show salt-specific effects on the transport properties of the gases when either KCl or CaCl₂ brines are considered, although adsorption was not affected. The acid gases considered either facilitate or hinder CH₄ transport depending on whether they are more or less preferentially adsorbed within the pore as compared to benzene, and this effect is mediated by the presence of water/brines. Our simulation results could be used to extract thermodynamic quantities that in the future will help to optimize transport of various gases through organic-rich and brine-bearing sedimentary rocks, which is likely to have a positive impact on both hydrocarbon production and carbon sequestration applications. As a first step, a phenomenological model is presented here, which allows one to predict permeability based on interatomic energies.

Acute acral eruptions in children during the COVID-19 pandemic: Characteristics of 103 children and their family clusters

Background

A marked increase in frequency of acute acral eruptions (AAE) was observed in children during the COVID-19 pandemic in the spring period.

Objectives

In this observational multicenter study, based on children with AAE, we aimed to assess the proportion of household members possibly infected by SARS-CoV-2.

Methods

We collected data from all children observed with AAE, prospectively from April 7, 2020 to June 22, 2020, and retrospectively since February 28, 2020. The primary outcome was the household infection rate, defined as the proportion of family clusters having at least one member with COVID-19 infection other than the child with AAE (“index child”). The definition of a case was based on characteristic clinical signs and a positive PCR or serology.

Results

The study included 103 children in 10 French departments and in Quebec. The median age was 13 years and the interquartile range [8–15], with a female-to-male ratio of 1/1.15. In children with AAE, all PCR tests were negative (n = 18), and serology was positive in 2/14 (14.3%) cases. We found no significant anomalies in the lab results. A total of 66 of the 103 families (64.1%) of included children had at least one other infected member apart from the index child. The total number of household members was 292, of whom 119 (40.8%) were considered possibly infected by SARS-CoV-2. No index children or households exhibited severe COVID-19.

Discussion

Among the 103 households included, 64.1% had at least one infected member. Neither children with AAE nor their households showed severe COVID-19.

What's really 'Happning'? A forensic analysis of Android and iOS Happn dating apps

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Forensic analysis of Android and iOS Happn dating apps.

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iTunes backup artifacts from Happn mobile app forensics.

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Physical image and network traffic artifacts from Happn forensics.

With today’s world revolving around online interaction, dating applications (apps) are a prime example of how people are able to discover and converse with others that may share similar interests or lifestyles, including during the recent COVID-19 lockdowns. To connect the users, geolocation is often utilized. However, with each new app comes the possibility of criminal exploitation. For example, while apps with geolocation feature are intended for users to provide personal information that drive their search to meet someone, that same information can be used by hackers or forensic analysts to gain access to personal data, albeit for different purposes. This paper examines the Happn dating app (versions 9.6.2, 9.7, and 9.8 for iOS devices, and versions 3.0.22 and 24.18.0 for Android devices), which geographically works differently compared to most notable dating apps by providing users with profiles of other users that might have passed by them or in the general radius of their location. Encompassing both iOS and Android devices along with eight varying user profiles with diverse backgrounds, this study aims to explore the potential for a malicious actor to uncover the personal information of another user by identifying artifacts that may pertain to sensitive user data.

Evidence of Facilitated Transport in Crowded Nanopores

Fluid transport in nature often occurs through crowded nanopores, where a number of phenomena can affect it, because of fluid-fluid and fluid-solid interactions, as well as the presence of organic compounds filling the pores and their structural fluctuations. Employing molecular dynamics, we probe here the transport of fluid mixtures (CO₂-CH₄ and H₂S-CH₄) through silica nanopores filled with benzene. Both CO₂ and H₂S are strongly adsorbed within the organic-filled pore, partially displacing benzene. Unexpectedly, CO₂/H₂S adsorption facilitates CH₄ transport. Analysis of the trajectories suggests that both CO₂ and H₂S act as vehicle-like carriers and might swell benzene, generating preferential transport pathways within the crowded pore. The results are useful for identifying unexpected transport mechanisms and for developing engineering approaches that could lead to storage of CO₂ in caprocks.

Effects of DNA Extraction and Purification Methods on Real-Time Quantitative PCR Analysis of Roundup Ready Soybean

The quality of DNA affects the accuracy and repeatability of quantitative PCR results. Different DNA extraction and purification methods were compared for quantification of Roundup Ready (RR) soybean (event 40-3-2) by real-time PCR. DNA was extracted using cetylmethylammonium bromide (CTAB), DNeasy Plant Mini Kit, and Wizard Magnetic DNA purification system for food. CTAB-extracted DNA was also purified using the Zymo (DNA Clean & Concentrator 25 kit), Qtip 100 (Qiagen Genomic-Tip 100/G), and QIAEX II Gel Extraction Kit. The CTAB extraction method provided the largest amount of DNA, and the Zymo purification kit resulted in the highest percentage of DNA recovery. The Abs260/280 and Abs260/230 ratios were less than the expected values for some of the DNA extraction and purification methods used, indicating the presence of substances that could inhibit PCR reactions. Real-time quantitative PCR results were affected by the DNA extraction and purification methods used. Further purification or dilution of the CTAB DNA was required for successful quantification of RR soybean. Less variability of quantitative PCR results was observed among experiments and replications for DNA extracted and/or purified by CTAB, CTAB+Zymo, CTAB+Qtip 100, and DNeasy methods. Correct and repeatable results for real-time PCR quantification of RR soybean were achieved using CTAB DNA purified with Zymo and Qtip 100 methods.

Patient and caregiver perceptions of lymphoma care and research opportunities: A qualitative study

BACKGROUND

Although the number of lymphoma survivors has increased, the needs and research priorities of survivors and their caregivers rarely are examined and addressed. Determining the needs and priorities for this population requires an assessment of the attitudes and experiences of patients and caregivers. The authors conducted a qualitative study with lymphoma survivors and their caregivers to determine care needs and research priorities.

METHODS

In the first phase, 2 semistructured focus groups were conducted with 15 lymphoma survivors and their caregivers. In phase 2, a total of 19 individual semistructured telephone interviews were conducted with lymphoma survivors and their caregivers. In both phases, participants discussed cancer experiences and research priorities. All interviews were transcribed. MAXQDA software (version 18.0.8) was used for coding and identifying themes.

RESULTS

The majority of participants felt disconnected from their clinical care team due to a lack of communication. Focus group participants noted a lack of information regarding diagnoses, treatment, research, and survivorship care. Participants coped with fear through strong social support and fostering relationships with their clinical care teams. Some caregivers felt completely ignored by clinicians. Participants expressed interest in research, but had difficulty finding relevant studies. Several interviewees desired holistic and survivorship-oriented research and more studies regarding quality of life and mental health.

CONCLUSIONS

The results of the current study identified unmet needs in clinical care and patient-oriented research, including needs for a focus on quality of life after treatment, communication between patients and the scientific community, and emotional well-being. Health care professionals can use these data to provide care delivery, supportive services, and research that meets the needs of lymphoma survivors and their caregivers.

Age-specific characteristics of neutrophilic dermatoses and neutrophilic diseases in children

BACKGROUND

Our suggested 'modern' concepts of 'neutrophilic dermatoses' (ND) and 'neutrophilic disease' were based on observations in adult patients and have not been studied in paediatric patients. Only a minority of ND occurs in children, and little is known about age-specific characteristics.

OBJECTIVES

To describe age-specific characteristics of ND in children and to study whether our suggested 'modern' classification of ND may be applied to children.

METHODS

We conducted a retrospective multicentre study in a French cohort of 27 paediatric patients diagnosed with pyoderma gangrenosum (PG) or Sweet's syndrome (SS).

RESULTS

Demographics and distribution of typical/atypical forms were similar in patients diagnosed with PG and SS. Atypical ND were more frequent in infants (90%), when compared to young children (60%) and adolescents (33%). Neutrophilic disease was observed in 17/27 patients and was most frequent in infants. Neutrophilic disease of the upper respiratory tract, as well as cardiac neutrophilic disease, was only observed in infants, whereas other locations were similarly found in infants, young children and adolescents. In infants and young children, ND were associated with a large spectrum of general diseases, whereas in adolescents associations were limited to inflammatory bowel disease and Behçet's disease.

CONCLUSIONS

Our study describes the concept of ND in paediatric patients and shows that they have some characteristics different from ND occurring in adults. ND occurring in infants can be associated with a large spectrum of general diseases. Occurrence of neutrophilic disease is frequent in children. Thus, ND occurring in young paediatric patients should incite clinicians to schedule complementary explorations in order to search for involvement of other organs and to rule out monogenetic autoinflammatory syndromes.

Incidence and outcomes of lymphoid malignancies in adolescent and young adult patients in the United States

Lymphoma incidence and survival in adolescent and young adult (AYA, defined as 15-39 years of age) and adult patients (>39 years) were assessed using Surveillance, Epidemiology, and End Results (SEER) data. From 2000 to 2014, 431 721 lymphoma cases were reported to SEER, 9% in AYA patients. In the AYA group, the highest age-adjusted incidence rate was for classical Hodgkin lymphoma [HL; 3·4 per 100 000 person-years; 95% confidence interval (CI), 3·38-3·49] followed by diffuse large B cell lymphoma (DLBCL; 1·56, 95% CI, 1·53-1·60) and for adults, it was plasma cell neoplasms (14·17, 95% CI, 14·07-14·27), DLBCL (13·86, 95% CI, 13·76-13·96) and chronic lymphocytic leukaemia (CLL; 13·19, 95% CI, 13·09-13·29). HL comprised 42% of lymphoma cases for AYAs, but only 4% in adults. The occurrence of DLBCL among AYAs and adults was similar, 18% and 20%, respectively. Twenty-eight percent of AYAs compared with 9% of adults presented with stage II disease, and 21% of AYAs compared with 10% of adults had B-symptoms. Extranodal disease was less common (33%) in AYAs than adults (59%). Overall, AYA patients with lymphoma have better 2- and 5-year relative survival rates (RSRs) compared to adults. When restricted to HL and DLBCL, RSR of AYA patients exceeds adult RSR.

Evidence of Structure-Performance Relation for Surfactants Used as Antiagglomerants for Hydrate Management

Molecular dynamics simulations were employed to study the structure of molecularly thin films of antiagglomerants adsorbed at the interface between sII methane hydrates and a liquid hydrocarbon. The liquid hydrocarbon was composed of dissolved methane and higher-molecular-weight alkane such as n-hexane, n-octane, and n-dodecane. The antiagglomerants considered were surface-active compounds with three hydrophobic tails and a complex hydrophilic head that contains both amide and tertiary ammonium cation groups. The length of the hydrophobic tails and the surface density of the compounds were changed systematically. The results were analyzed in terms of the preferential orientation of the antiagglomerants, density distributions of various molecular compounds, and other molecular-level properties. At low surface densities, the hydrophobic tails do not show preferred orientation, irrespectively of the tail length. At sufficiently high surface densities, our simulations show pronounced differences in the structure of the interfacial film depending on the molecular features and on the type of hydrocarbons present in the system. Some antiagglomerants are found to pack densely at the interface and exclude methane from the interfacial region. Under these conditions, the antiagglomerant film resembles a frozen interface. The hydrophobic tails of the antiagglomerants that show this feature has a length comparable to that of the n-dodecane in the liquid phase. It is possible that the structured interfacial layer is in part responsible for determining the performance of antiagglomerants in flow-assurance applications. The simulation results are compared against experimental data obtained with the rocking cell apparatus. It was found that the antiagglomerants for which our simulations suggest evidence of a frozen interface at sufficiently high surface densities are those that show better performance in rocking cell experiments.

Inclusion of Radiation Environment Variability in Total Dose Hardness Assurance Methodology

Variability of the space radiation environment is investigated with regard to parts categorization for total dose hardness assurance methods. It is shown that it can have a significant impact. A modified approach is developed that uses current environment models more consistently and replaces the radiation design margin concept with one of failure probability during a mission.

Confined Water Determines Transport Properties of Guest Molecules in Narrow Pores

We computed the transport of methane through 1 nm wide slit-shaped pores carved out of solid substrates. Models for silica, magnesium oxide, and alumina were used as solid substrates. The pores were filled with water. The results show that the methane permeability through the hydrated pores is strongly dependent on the solid substrate. Detailed analysis of the simulated systems reveals that local properties of confined water, including its structure, and more importantly, evolution of solvation free energy and hydrogen bond structure are responsible for the pronounced differences observed. The simulations are extended to multicomponent systems representative of natural gas, containing methane, ethane, and H2S. The results show that all pores considered have high affinity for H2S, moderate affinity for methane, and low affinity for ethane. The H2S/methane transport selectivity through the hydrated alumina pore is comparable, or superior, to that reported for existing commercial membranes. A multiscale approach was then implemented to demonstrate that a Smoluchowski one-dimensional model is able to reproduce the molecular-level results for short pores when appropriate values for the local self-diffusion coefficients are used as input parameters. We propose that the model can be extended to predict methane transport through uniform hydrated pores of macroscopic length. When verified by experiments, our simulation results could have important implications in applications such as natural gas sweetening and predictions of methane migration through hydraulically fractured shale formations.

Integrating understanding of epidemiology and genomics in B-cell non-Hodgkin lymphoma as a pathway to novel management strategies

Non-Hodgkin lymphomas include a biologically and clinically heterogeneous group of cancers distinguished by genetics, histology, and treatment outcomes. New discoveries regarding the genomic alterations and epidemiological exposures associated with these lymphomas have enhanced our understanding of factors that contribute to lymphomagenesis for specific subtypes. We explore the impact of normal B-cell biology engineered for recognizing a wide variety of antigens on the development of specific lymphoma subtypes, review lymphoma genetics, and examine the epidemiology of B-cell NHLs including recent investigations of risk factors for particular lymphoma subtypes based on large pooled analyses. Burkitt lymphoma, an aggressive form of B-cell NHL involving translocation of the MYC gene and an immunoglobulin gene has been associated with a history of eczema, hepatitis C, and occupation as a cleaner. Increased risk of diffuse large B-cell lymphoma has been associated with increased young adult body mass index, history of B-cell-activating autoimmune diseases, hepatitis C, and several single nucleotide variants involving the human leukocyte antigen (HLA) region of chromosome 6 and non-HLA loci near EXOC2, PVT1, MYC, and NCOA1. Tumor sequencing studies suggest that multiple pathways are involved in the development of DLBCL. Additional studies of epidemiological exposures, genome wide associations, and tumor sequencing in follicular, lymphoplasmacytic, marginal zone, and mantle cell lymphoma demonstrate overlapping areas of increased risk factors and unique factors for specific subtypes. Integrating these findings is important for constructing comprehensive models of NHL pathogenesis, which could yield novel targets for therapy and strategies for lymphoma prevention in certain populations.