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1.
Proc Natl Acad Sci U S A ; 120(45): e2220518120, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37903276

RESUMO

Structural details of a genome packaged in a viral capsid are essential for understanding how the structural arrangement of a viral genome in a capsid controls its release dynamics during infection, which critically affects viral replication. We previously found a temperature-induced, solid-like to fluid-like mechanical transition of packaged λ-genome that leads to rapid DNA ejection. However, an understanding of the structural origin of this transition was lacking. Here, we use small-angle neutron scattering (SANS) to reveal the scattering form factor of dsDNA packaged in phage λ capsid by contrast matching the scattering signal from the viral capsid with deuterated buffer. We used small-angle X-ray scattering and cryoelectron microscopy reconstructions to determine the initial structural input parameters for intracapsid DNA, which allows accurate modeling of our SANS data. As result, we show a temperature-dependent density transition of intracapsid DNA occurring between two coexisting phases-a hexagonally ordered high-density DNA phase in the capsid periphery and a low-density, less-ordered DNA phase in the core. As the temperature is increased from 20 °C to 40 °C, we found that the core-DNA phase undergoes a density and volume transition close to the physiological temperature of infection (~37 °C). The transition yields a lower energy state of DNA in the capsid core due to lower density and reduced packing defects. This increases DNA mobility, which is required to initiate rapid genome ejection from the virus capsid into a host cell, causing infection. These data reconcile our earlier findings of mechanical DNA transition in phage.


Assuntos
Bacteriófago lambda , Capsídeo , Bacteriófago lambda/genética , Capsídeo/química , Temperatura , Microscopia Crioeletrônica , DNA Viral/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/análise
2.
J Biol Chem ; 300(3): 105717, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38311178

RESUMO

AMPA-type ionotropic glutamate receptors (AMPARs) are central to various neurological processes, including memory and learning. They assemble as homo- or heterotetramers of GluA1, GluA2, GluA3, and GluA4 subunits, each consisting of an N-terminal domain (NTD), a ligand-binding domain, a transmembrane domain, and a C-terminal domain. While AMPAR gating is primarily controlled by reconfiguration in the ligand-binding domain layer, our study focuses on the NTDs, which also influence gating, yet the underlying mechanism remains enigmatic. In this investigation, we employ molecular dynamics simulations to evaluate the NTD interface strength in GluA1, GluA2, and NTD mutants GluA2-H229N and GluA1-N222H. Our findings reveal that GluA1 has a significantly weaker NTD interface than GluA2. The NTD interface of GluA2 can be weakened by a single point mutation in the NTD dimer-of-dimer interface, namely H229N, which renders GluA2 more GluA1-like. Electrophysiology recordings demonstrate that this mutation also leads to slower recovery from desensitization. Moreover, we observe that lowering the pH induces more splayed NTD states and enhances desensitization in GluA2. We hypothesized that H229 was responsible for this pH sensitivity; however, GluA2-H229N was also affected by pH, meaning that H229 is not solely responsible and that protons exert their effect across multiple domains of the AMPAR. In summary, our work unveils an allosteric connection between the NTD interface strength and AMPAR desensitization.


Assuntos
Receptores de AMPA , Humanos , Células HEK293 , Ligantes , Simulação de Dinâmica Molecular , Mutação , Domínios Proteicos , Receptores de AMPA/genética , Receptores de AMPA/metabolismo , Regulação Alostérica
3.
Methods ; 223: 127-135, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331125

RESUMO

Biological membranes are highly complex supramolecular assemblies, which play central roles in biology. However, their complexity makes them challenging to study their nanoscale structures. To overcome this challenge, model membranes assembled using reduced sets of membrane-associated biomolecules have been found to be both excellent and tractable proxies for biological membranes. Due to their relative simplicity, they have been studied using a range of biophysical characterization techniques. In this review article, we will briefly detail the use of fluorescence and electron microscopies, and X-ray and neutron scattering techniques used over the past few decades to study the nanostructure of biological membranes.


Assuntos
Microscopia , Nêutrons , Biofísica , Membrana Celular , Lipídeos
4.
J Neurophysiol ; 131(5): 785-788, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38533966

RESUMO

The etiology of spaceflight-associated neuro-ocular syndrome (SANS) is a developing field of research, with many current hypotheses receiving varying degrees of support. This syndrome affects ∼70% of astronauts both during and after long-duration space missions, resulting in impaired near vision and visual scotomas (blind spots). In this article, three prominent risk factors for SANS including zero gravity conditions, extraterrestrial hypercapnic environments, and individual genetic predisposition are described. These risk factors are then compared and their pathophysiological pathways are divided into five current hypotheses for the development of SANS. Finally, glymphatic system impairment is explored as a potential mutual end point for these pathways in the development of SANS.


Assuntos
Sistema Glinfático , Voo Espacial , Humanos , Sistema Glinfático/fisiopatologia , Transtornos da Visão/etiologia , Transtornos da Visão/fisiopatologia
5.
Can J Psychiatry ; : 7067437241246589, 2024 Apr 24.
Artigo em Francês | MEDLINE | ID: mdl-38656192

RESUMO

OBJECTIVE: Ambulatory care without consent is widely used, but it is controversial, and its effectiveness has not yet been proven. The patient experience remains largely unstudied in France, particularly that of young patients, yet their adherence to care in the early stages of the disease is complex and has an impact on their prognoses. The aim of this study is to investigate the experience of young patients undergoing a program of care (POC) in order to suggest ways of optimizing their care and to enrich the debate on the use of POCs. METHOD: Semi-structured interviews were conducted with 11 patients between ages 20 and 32, who were either undergoing a POC or had done so in the previous 5 years, followed by a semi-pragmatic phenomenological analysis of the resulting transcripts. RESULTS: (1) The outpatient experience with restraints is contradictory, ranging from deprivation and intrusion to support and protection. (2) The POC is portrayed as a framework for developing awareness of disorders and acceptance of care. (3) Patients report a lack of information about care with restraints, even to the point of being unaware of its existence. Patient-psychiatrist interactions within the POC are complicated by the restraints, but remain perceived as a care relationship. (4) They report constraints in their daily lives in connection to the POC, which can complicate professional involvement. CONCLUSION: The results support the importance of nurturing the therapeutic relationship within the POC and involving patients more in their care, starting with better information. They support the use of POCs as a temporary tool to be combined with work on adherence to treatment and support for social and professional reintegration. SPECIALTY: Psychiatry.


OBJECTIF: Les dispositifs de soins ambulatoires sans consentement sont largement utilisés, mais ils sont controversés et leur efficacité n'est pas prouvée à ce jour. L'expérience des patients concernés reste très peu étudiée en France, et notamment celui des jeunes patients, or leur adhésion aux soins en début de maladie est complexe et a un impact sur le pronostic futur. L'objectif est d'étudier l'expérience de jeunes patients suivis en programme de soins (PDS) afin de proposer des perspectives pour optimiser leur prise en charge et d'enrichir la réflexion sur l'utilisation des PDS. MÉTHODE: Des entretiens semi-directifs ont été réalisés auprès de 11 patients de 20 à 32 ans suivis en PDS ou l'ayant été dans les 5 dernières années, puis une analyse phénoménologique de type sémio-pragmatique a été réalisée sur les verbatims obtenus. RÉSULTATS: (1) L'expérience de la contrainte en ambulatoire est contrastée avec un vécu de privation de libertés et d'intrusion, mais aussi de soutien et de protection. (2) Le PDS est représenté comme un cadre permettant l'évolution de la conscience des troubles et de l'acceptation des soins. (3) Les patients rapportent un manque d'information sur les modalités de soins sous contrainte, pouvant aller jusqu'à la méconnaissance de l'existence de cette mesure. Les interactions patient-psychiatre au sein du PDS sont complexifiées par la contrainte mais restent perçues comme une relation de soin. (4) Ils rapportent des contraintes dans la vie quotidienne liées au PDS et qui peuvent compliquer l'insertion professionnelle. CONCLUSION: Les résultats soutiennent l'importance de soigner la relation thérapeutique au sein du PDS et d'impliquer davantage le patient dans sa prise en charge, en commençant par une meilleure information. Ils soutiennent une utilisation du PDS comme un outil temporaire à associer à un travail sur l'adhésion aux soins et à un accompagnement à la réinsertion sociale et professionnelle. SPÉCIALITÉ: Psychiatrie.

6.
Proc Natl Acad Sci U S A ; 118(4)2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33468682

RESUMO

Growth of plastic waste in the natural environment, and in particular in the oceans, has raised the accumulation of polystyrene and other polymeric species in eukyarotic cells to the level of a credible and systemic threat. Oligomers, the smallest products of polymer degradation or incomplete polymerization reactions, are the first species to leach out of macroscopic or nanoscopic plastic materials. However, the fundamental mechanisms of interaction between oligomers and polymers with the different cell components are yet to be elucidated. Simulations performed on lipid bilayers showed changes in membrane mechanical properties induced by polystyrene, but experimental results performed on cell membranes or on cell membrane models are still missing. We focus here on understanding how embedded styrene oligomers affect the phase behavior of model membranes using a combination of scattering, fluorescence, and calorimetric techniques. Our results show that styrene oligomers disrupt the phase behavior of lipid membranes, modifying the thermodynamics of the transition through a spatial modulation of lipid composition.


Assuntos
1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , Bicamadas Lipídicas/química , Lipossomos/química , Fosfatidilcolinas/química , Poliestirenos/química , Água do Mar/química , 1,2-Dipalmitoilfosfatidilcolina/química , Deutério/química , Humanos , Cinética , Transição de Fase , Temperatura , Termodinâmica , Poluição da Água
7.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34815346

RESUMO

Amyloid fibrils are associated with a number of neurodegenerative diseases, including fibrils of amyloid ß42 peptide (Aß42) in Alzheimer's disease. These fibrils are a source of toxicity to neuronal cells through surface-catalyzed generation of toxic oligomers. Detailed knowledge of the fibril structure may thus facilitate therapeutic development. We use small-angle scattering to provide information on the fibril cross-section dimension and shape for Aß42 fibrils prepared in aqueous phosphate buffer at pH = 7.4 and pH 8.0 under quiescent conditions at 37 °C from pure recombinant Aß42 peptide. Fitting the data using a continuum model reveals an elliptical cross-section and a peptide mass-per-unit length compatible with two filaments of two monomers, four monomers per plane. To provide a more detailed atomistic model, the data were fitted using as a starting state a high-resolution structure of the two-monomer arrangement in filaments from solid-state NMR (Protein Data Bank ID 5kk3). First, a twofold symmetric model including residues 11 to 42 of two monomers in the filament was optimized in terms of twist angle and local packing using Rosetta. A two-filament model was then built and optimized through fitting to the scattering data allowing the two N-termini in each filament to take different conformations, with the same conformation in each of the two filaments. This provides an atomistic model of the fibril with twofold rotation symmetry around the fibril axis. Intriguingly, no polydispersity as regards the number of filaments was observed in our system over separate samples, suggesting that the two-filament arrangement represents a free energy minimum for the Aß42 fibril.


Assuntos
Peptídeos beta-Amiloides/química , Neurônios/metabolismo , Fragmentos de Peptídeos/química , Doença de Alzheimer/metabolismo , Amiloide/química , Catálise , Microscopia Crioeletrônica , Bases de Dados de Proteínas , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Modelos Moleculares , Conformação Molecular , Doenças Neurodegenerativas/metabolismo , Peptídeos/química , Conformação Proteica , Espalhamento de Radiação , Espalhamento a Baixo Ângulo , Raios X
8.
Int J Mol Sci ; 25(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38474237

RESUMO

The clinical benefits of using exogenous pulmonary surfactant (EPS) as a carrier of budesonide (BUD), a non-halogenated corticosteroid with a broad anti-inflammatory effect, have been established. Using various experimental techniques (differential scanning calorimetry DSC, small- and wide- angle X-ray scattering SAXS/WAXS, small- angle neutron scattering SANS, fluorescence spectroscopy, dynamic light scattering DLS, and zeta potential), we investigated the effect of BUD on the thermodynamics and structure of the clinically used EPS, Curosurf®. We show that BUD facilitates the Curosurf® phase transition from the gel to the fluid state, resulting in a decrease in the temperature of the main phase transition (Tm) and enthalpy (ΔH). The morphology of the Curosurf® dispersion is maintained for BUD < 10 wt% of the Curosurf® mass; BUD slightly increases the repeat distance d of the fluid lamellar phase in multilamellar vesicles (MLVs) resulting from the thickening of the lipid bilayer. The bilayer thickening (~0.23 nm) was derived from SANS data. The presence of ~2 mmol/L of Ca2+ maintains the effect and structure of the MLVs. The changes in the lateral pressure of the Curosurf® bilayer revealed that the intercalated BUD between the acyl chains of the surfactant's lipid molecules resides deeper in the hydrophobic region when its content exceeds ~6 wt%. Our studies support the concept of a combined therapy utilising budesonide-enriched Curosurf®.


Assuntos
Surfactantes Pulmonares , Budesonida , Espalhamento a Baixo Ângulo , Difração de Raios X , Termodinâmica , Bicamadas Lipídicas/química , Varredura Diferencial de Calorimetria , Pulmão , Tensoativos
9.
Encephale ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38729799

RESUMO

Autistic people without Intellectual Developmental Disorders (IDD) have a significantly lower employment rate compared to the general population even though employment favors social integration and quality of life. AIMS: To examine the barriers and facilitators to employability in mainstream settings for autistic adults without intellectual disability. METHODS: Following the scoping review guidelines, we searched the Cochrane, PubMed and PsycINFO databases for references published between 01/01/2000 to 01/08/2023. RESULTS: A review of the 44 identified articles suggests the existence of multiple individual and environmental factors influencing job access and retention. CONCLUSIONS: This is the first review to assess the facilitators and barriers to employment support for autistic people without intellectual disability. The results underline the need for studying strategies to promote access to employment and job retention for autistic people. Future research should explore the mediating and moderating factors leading to the improvement of employability of autistic people WIDD.

10.
Encephale ; 50(3): 309-328, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38326137

RESUMO

Attention Deficit Disorder with or without Hyperactivity (ADHD is a neurodevelopmental disorder which affects the day-to-day functioning of children and adults with this condition. Pharmacological treatment can reduce the symptoms associated with ADHD, but it has some limitations. The objective of this symposium is to determine the effects of non-pharmacological approaches on ADHD symptoms. Results indicate that the following intervention are promising approaches: cognitive behavioral therapy (CBT), mindfulness-based interventions (MBI), yoga, cognitive and metacognitive intervention, neurofeedback and parental training programs. Current research advocates multimodal approaches in conjunction with school or work accommodations integrating innovative technologies.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Terapia Cognitivo-Comportamental , Atenção Plena , Neurorretroalimentação , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Terapia Cognitivo-Comportamental/métodos , Neurorretroalimentação/métodos , Atenção Plena/métodos , Criança , Yoga , Adulto , Terapia Combinada
11.
Ann Chir Plast Esthet ; 69(2): 154-159, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37423823

RESUMO

INTRODUCTION: Malignant non-melanoma skin cancers (NMSC) are of two main types: basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). In rare occasions, some of the malignant skin lesions show histopathological characteristics of both BCC and SCC and are known as basosquamous carcinomas (BSC). In some cases of large tumors, extensive reconstructive surgery might be needed to correct the skin defect after the primary excision. PRESENTATION OF CASE: We report a case of a 76-year-old Bulgarian male patient who presented with a neglected giant cutaneous tumor with more than a 15-year history of a growing mass in the right deltoid area. On physical exam an enormous exophytic ulcerated and crusted skin lesion measuring around 11×11cm was found. Wide local excision of the lesion with 10-mm resection margins and partial resection of the underlying deltoid muscle were performed due to signs of infiltration. A full-thickness total skin graft from the left inguinal area was harvested to cover the skin defect. Final histopathological examination showed metatypical carcinoma with mixed characteristics of SCC and BCC - BSC, with infiltration of the fatty tissue, deltoid muscle and clear margins of resection, staged as T4R0. Two and a half years after surgery there are no signs of upper arm motor dysfunction and no evidence of local recurrence and distant metastasis on a follow-up PET/CT. DISCUSSION: Following current National Comprehensive Cancer Network's guidelines for primary treatment of BCC, surgical candidates should undergo standard excision with wider surgical margins, postoperative margin assessment and second intention healing, linear repair, or skin graft. Therapeutic strategy for non-operable cases includes administration of radiotherapy or system therapy in the face of Hedgehog pathway inhibitors and programmed cell death protein 1 inhibitor. They can provide an alternative solution to unresectable or difficult-to-treat locally advanced cases of BSC. CONCLUSION: Similarly to BCC and SCC, the first-line treatment option for BCS is surgical excision, but surgical margins should be wider than those for low-risk BCC due to the infiltrative growth pattern of this tumor. Favorable esthetic outcome requires precise planning of the reconstructive technique.


Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutâneas , Masculino , Humanos , Idoso , Margens de Excisão , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Proteínas Hedgehog , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Carcinoma Basocelular/cirurgia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/cirurgia
12.
Soins Psychiatr ; 45(352): 13-16, 2024.
Artigo em Francês | MEDLINE | ID: mdl-38719353

RESUMO

A group-based online psycho-education program for adults with attention deficit hyperactivity disorder (ADHD) and their families has been set up by a multi-professional psychiatric team. Feedback from users has mainly shown benefits in terms of improving self-esteem, destigmatization and accessibility to care. This suggests a real interest in developing this care offer in the pathway of ADHD adults.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Educação de Pacientes como Assunto , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/enfermagem , Adulto , Autoimagem , Psicoterapia de Grupo/métodos , França , Masculino , Feminino , Criatividade , Instrução por Computador , Comunicação Interdisciplinar , Equipe de Assistência ao Paciente , Estigma Social , Colaboração Intersetorial , Internet , Acessibilidade aos Serviços de Saúde , Comportamento Cooperativo
13.
J Biol Chem ; 298(8): 102253, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35835218

RESUMO

Highly deuterated protein samples expand the biophysics and biological tool kit by providing, among other qualities, contrast matching in neutron diffraction experiments and reduction of dipolar spin interactions from normally protonated proteins in magnetic resonance studies, impacting both electron paramagnetic resonance and NMR spectroscopy. In NMR applications, deuteration is often combined with other isotopic labeling patterns to expand the range of conventional NMR spectroscopy research in both solution and solid-state conditions. However, preparation of deuterated proteins is challenging. We present here a simple, effective, and user-friendly protocol to produce highly deuterated proteins in Escherichia coli cells. The protocol utilizes the common shaker flask growth method and the well-known pET system (which provides expression control via the T7 promotor) for large-scale recombinant protein expression. One liter expression typically yields 5 to 50 mg of highly deuterated protein. Our data demonstrate that the optimized procedure produces a comparable quantity of protein in deuterium (2H2O) oxide M9 medium compared with that in 1H2O M9 medium. The protocol will enable a broader utilization of deuterated proteins in a number of biophysical techniques.


Assuntos
Biofísica , Deutério , Proteínas Recombinantes , Biofísica/métodos , Deutério/química , Escherichia coli/genética , Escherichia coli/metabolismo , Marcação por Isótopo , Difração de Nêutrons , Proteínas Recombinantes/metabolismo
14.
Mol Pharm ; 20(12): 6358-6367, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-37961914

RESUMO

Understanding protein dynamics and conformational stability holds great significance in biopharmaceutical research. Hydrogen-deuterium exchange (HDX) is a quantitative methodology used to examine these fundamental properties of proteins. HDX involves measuring the exchange of solvent-accessible hydrogens with deuterium, which yields valuable insights into conformational fluctuations and conformational stability. While mass spectrometry is commonly used to measure HDX on the peptide level, we explore a different approach using small-angle neutron scattering (SANS). In this work, SANS is demonstrated as a complementary and noninvasive HDX method (HDX-SANS). By assessing subtle changes in the tertiary and quaternary structure during the exchange process in deuterated buffer, along with the influence of added electrolytes on protein stability, SANS is validated as a complementary HDX technique. The HDX of a model therapeutic antibody, NISTmAb, an IgG1κ, is monitored by HDX-SANS over many hours using several different formulations, including salts from the Hofmeister series of anions, such as sodium perchlorate, sodium thiocyanate, and sodium sulfate. The impact of these formulation conditions on the thermal stability of NISTmAb is probed by differential scanning calorimetry. The more destabilizing salts led to heightened conformational dynamics in mAb solutions even at temperatures significantly below the denaturation point. HDX-SANS is demonstrated as a sensitive and noninvasive technique for quantifying HDX kinetics directly in mAb solution, providing novel information about mAb conformational fluctuations. Therefore, HDX-SANS holds promise as a potential tool for assessing protein stability in formulation.


Assuntos
Medição da Troca de Deutério , Hidrogênio , Hidrogênio/química , Deutério/química , Espalhamento a Baixo Ângulo , Medição da Troca de Deutério/métodos , Conformação Proteica , Sais
15.
Environ Sci Technol ; 57(26): 9802-9810, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37347651

RESUMO

Aggregation of humic acids (HAs) was studied by small-angle neutron and X-ray scattering techniques. The combination of these techniques enables us to examine the aggregation structures of HA particles. Two HAs with distinctive compositions were examined: a commercial HA (PAHA) and a HA extracted from deep sedimentary groundwater (HHA). While macroscopic coagulation tests showed that these HAs were stable in solutions except for HHA at pH < 6, small-angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS) revealed that they formed aggregates with sizes exceeding the sub-micrometer length scale. The SAXS curves of PAHA remarkably varied with pD = log aD+, where aD+ stands for the activity of deuterium ions, whereas the SANS curves did not. With the help of theoretical fittings, it was revealed that PAHA aggregates consisted of two domains: poorly hydrated cores and well-hydrated proton-rich shells. The cores were (dis)aggregated with pD inside the aggregates of the shells. The SANS and SAXS curves of HHA resembled each other, and their intensities at low q, where q stands for the scattering vector, increased with a decrease of pD, indicating the formation of homogeneous aggregates within the spatial resolutions of SANS and SAXS. This study revealed that distinctive aggregation behaviors exist in humic substances with nm-scale heterogeneous structures like PAHA, which is important for their roles in the fate of contaminants or nutrients in aqueous environments.


Assuntos
Substâncias Húmicas , Difração de Nêutrons , Espalhamento a Baixo Ângulo , Raios X , Difração de Nêutrons/métodos , Difração de Raios X
16.
Microsc Microanal ; 29(2): 437-450, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37749737

RESUMO

Identifying the operative mode of phase separation [spinodal decomposition (SD) or nucleation-growth (NG)] remains an extremely important area of research. The present work examines this critically in the Fe-Cr system using atom probe tomography (APT) and small angle neutron scattering (SANS), and establishes the framework to distinguish the two different modes of α' phase separation in thermally aged Fe-35 at% Cr and Fe-20 at% Cr alloys. Independent APT analysis determines the mode of phase separation on the basis of (i) the presence/absence of periodic chemical fluctuation through radial distribution function analysis and (ii) interphase interface characteristics (diffuse/sharp). SANS analysis, in contrast, yields virtually indistinguishable correlation peaks for both the modes, which necessitates further investigation of the several different aspects of SANS profiles in the light of APT results. For the first time, key features of SANS profiles have been identified that can unambiguously distinguish SD from NG in the Fe-Cr system: (i) nature of temporal evolution of FWHM of the correlation peak and (ii) appropriate value of γ for fitting with the dynamic scaling model (γ = 6 for SD, Fe-35 at% Cr alloy; γ = 4 for NG, Fe-20 at% Cr alloy).

17.
Can J Diet Pract Res ; 84(2): 63-68, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36412507

RESUMO

Purpose: When admitted to the hospital, individuals with celiac disease rely on food handlers for provision of safe, uncontaminated gluten-free meals. We aimed to assess the knowledge of gluten-free diet (GFD) amongst individuals involved in meal preparation for patients.Methods: A questionnaire with 10 demographic and 35 test items to assess knowledge of GFD, including workplace scenarios encountered in meal preparation, was administered to food handlers including cooks, utility workers, dietary technicians, and supervisors in 2 tertiary care, university-affiliated hospitals. A score of ≥28 of 35 (≥80%) was considered a "pass".Results: A total of 72 individuals completed the study, mean age 40.3 ± 1.6 years, 75% female. Only 42 (56.8%) scored ≥80% and achieved a pass. The average score was 75.9% ± 13.4%, range 25.7%-100%. The supervisors had significantly higher scores (87.9% ± 11.4%) than utility workers (73.0% ± 11.4%; P = 0.01) and cooks (71.7% ± 14.5%; P = 0.01). Cooks had the lowest scores with 80% scoring <80%. Females scored higher than males (77.8% vs. 68.8%; P = 0.02).Conclusions: There are significant differences in GFD knowledge amongst various groups involved in food preparation in hospitals. The gaps identified in knowledge can potentially compromise the safety of patients with celiac disease. Targeted interventions to educate hospital food handlers about GFD are warranted. Registered Dietitians can play an important role in providing this education.


Assuntos
Doença Celíaca , Dieta Livre de Glúten , Masculino , Humanos , Feminino , Adulto , Inquéritos e Questionários , Hospitais , Refeições
18.
Encephale ; 49(2): 165-173, 2023 Apr.
Artigo em Francês | MEDLINE | ID: mdl-35725514

RESUMO

OBJECTIVES: In France, a systematic control of compulsory psychiatric admissions has existed since the enactment of the law of July 5th 2011. The Court of Cassation clarified that the liberty and custody judges (JLD) cannot supersede the medical opinion described in the medical certificates. In 2015, the JLD ordered the release of 8.4 % of all compulsory psychiatric admissions. The goal was to compare the quality of medical certificates derived from judicial release based on medical grounds with non-released witnesses from the cohort of compulsory psychiatric admissions ordered in the Groupe Hospitalier Universitaire Paris Psychiatrie & Neurosciences (GHU-Paris) between November 1, 2017 and October 31, 2018. METHODS: We included as cases all the medical certificates derived from judicial release based exclusively on medical grounds from the release cohort of the GHU-Paris from November 1, 2017 to October 31, 2018, concerning the systematic control 12 days after compulsory psychiatric admissions. A witness whose compulsory care had been maintained was matched according to the same judge, place and date of hearing, mode of compulsory care and site of hospitalization. Each certificate was analyzed according to a reading grid relating to the good decisions in matters of compulsory admission and medical certificates' redaction. An overall score, based on the description of the clinical and symptomatic evolution, the level of discernment, the capacity of consent and the mode of compulsory care was awarded to each certificate. RESULTS: Seventeen release files were included in the comparative study. Globally, the clinical progression, psychiatric symptoms, level of consciousness and ability to consent did not differ in the two groups. The grade of quality of certificate was lower in case of withdrawal (2.92±1.08 VS 3.28±0.88, P=0.026). Psychiatric symptoms in "justifiable notice" (the last medical certificate prior to the judicial hearing) were less specified in case of withdrawal (58.8 % VS 94.1 %, P=0.015). Not describing any symptoms led to a 12.51 risk of withdrawal (95 % CI=[1.16; 135.19], P=0.038). Even with witness certificate, clinical progression was noticed in only 85.3 % of cases, in 89.3 % of psychiatric symptoms, in 68.0 % of level of consciousness and 80.0 % for the ability to consent. CONCLUSIONS: Judiciary releases of compulsory psychiatric admissions exclusively based on medical grounds are not arbitrarily decided by the JLD but are based on a failure to draw up medical certificates. Doctors must comply with a careful drafting of all medical certificates: description of symptoms, clinical course, level of consciousness and ability to consent. It is necessary to be attentive to judiciary releases based on medical grounds to evaluate and improve medical practices concerning the drafting of medical certificates.


Assuntos
Internação Compulsória de Doente Mental , Hospitalização , Humanos , França , Paris , Transtorno da Personalidade Antissocial
19.
Ann Chir Plast Esthet ; 68(3): 194-203, 2023 Jun.
Artigo em Francês | MEDLINE | ID: mdl-35902287

RESUMO

INTRODUCTION: Long finger skeletal fractures are common injuries. In displaced forms, surgical treatment is required. With the advent of headless cannulated screws, the technique has been simplified and allows reduction in both planes. The objective of our study was to evaluate the functional recovery of patients operated on by this technique. MATERIAL AND METHOD: We conducted a retrospective single-center study between 2019 and 2022. Eleven patients were followed and 12 fractures analyzed. A radio-clinical follow-up was carried out at 1 month then at the last follow-up with an evaluation of the articular amplitudes and a quality of life score (QuickDash, QD). The time to return to professional and sporting activities, pain (EVA) was collected. An anatomical/scannographic evaluation was performed to assess tendon and cartilage damage. RESULTS: At the last follow-up, the average global flexion was 266° and the extension was total. An average QD score of 15.9 and a Jamar force of 106% compared to the healthy side were observed. The return to physical and professional activities was earlier and the pain quickly tolerable. No secondary displacement was objectified and all were consolidated at the last follow-up, without malunion. No patient had been operated on secondarily. CONCLUSION: This technique seems to be a safe and non-traumatic. It allows a faster return to sports and professional activities with fewer complications and no need to remove the material.


Assuntos
Traumatismos dos Dedos , Fraturas Ósseas , Humanos , Estudos Retrospectivos , Qualidade de Vida , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Parafusos Ósseos
20.
Prog Urol ; 33(13): 718-732, 2023 Nov.
Artigo em Francês | MEDLINE | ID: mdl-38012914

RESUMO

CONTEXT: Contraception is a major global health issue, which is still dominated by female contraception. Developments in male contraception could help redistribute the contraceptive burden. METHODS: A literature search was carried out to review the existing options and the criteria for optimal contraception, to establish the principles of a male pre-contraception consultation, and to review the various research avenues with their advantages and disadvantages. RESULTS: The new male contraception options are detailed, whether hormonal (androgen therapy, combination of progestins and testosterone) or non-hormonal, particularly thermal, with current results and avenues for improvement. Condom use and vasectomy remain the only 2 validated options. The recent development of minimally invasive vasectomy without the need for a scalpel and of occlusion techniques has simplified the procedure, minimised the risk of complications (pain, haematomas, post-vasectomy pain syndrome) and improved efficacy. The issues of regret and the possibility of repermeabilisation are also raised. CONCLUSION: The question of male contraception will become increasingly important in consultations with urologists. The urologist will have to inform the patient, as required by law, before the vasectomy is performed, and provide the best possible advice on the technique, which will often be minimally invasive without the need for a scalpel. New reversible options should also broaden the range of options available on a routine basis, with a view to gradually moving towards contraceptive equity.


Assuntos
Anticoncepcionais Masculinos , Vasectomia , Masculino , Humanos , Feminino , Anticoncepção/métodos , Anticoncepcionais , Dor
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