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We have investigated the growth of the c-axis oriented aluminum nitride (AlN) thin films on (100) silicon by reactive dc magnetron sputtering at low temperature, considering the effect of the magnet configuration on plasma and film properties. It appears that a magnet modification can significantly modify both the plasma characteristics and the film properties. Electrical and optical characterizations of the plasma phase highlight that depending on the magnet configuration, two very different types of deposition process can be involved in the same deposition chamber. On the one hand, with a balanced magnetron (type 1), the deposition process enhances the production of AlN dimers in the plasma phase and enables to synthesize AlN films with different preferential orientations (100, 002, and even 101). On the other hand, a strongly unbalanced magnetron (type 2) provides a limited production of AlN species in the plasma phase and a strong increase in the ratio of ions to metal atom flux on the growing films. In the latter case, the ion energy provided by the ion flux to the growing film is typically in the 20–30 eV range. Thus, dense (002) oriented films with high crystalline quality are obtained without any substrate heating. [ABSTRACT FROM AUTHOR]

The relationship between thermal conductivity and microstructures of aluminium nitride films is reported. Films were deposited on silicon substrates by magnetron sputtering of a pure Al target in nitrogen argon plasma at low temperatures (<300 ?C) with thickness ranging from 150 to 3500 nm. Balanced and unbalanced magnetron configurations were used for different nitrogen contents in the gas phase. Various microstructures were thus created and their thermal conductivity was measured with the transient hot strip technique. Depending on the crystalline structure of the films, the bulk thermal conductivity of the AlN films at room temperature varied between 2 and 170Wm-1 K-1. Unbalanced magnetron allowed achieving highly dense (0 0 2) oriented AlN films with a grain size in the 100 nm range, a low oxygen content close to 0.5 at% and a resulting bulk thermal conductivity as high as 170Wm-1 K-1. Such a crystalline quality resulted from the ion energy involved in the growth process. In contrast, balanced magnetron led to weakly textured AlN films containing 5 at% oxygen with a grain size in the 30 nm range and a resulting thermal conductivity ranging from 2 to 100Wm-1 K-1 depending on the microstructure. Otherwise, the thermal boundary resistance between AlN films deposited by unbalanced magnetron and the silicon substrate was found to be as low as 1.0 × 10-8Km2W-1. Such a value was in good agreement with the thickness of the interfacial amorphous layer determined in the 2 nm range by high resolution transmission electron microscopy. [ABSTRACT FROM AUTHOR]

A factor activating human platelets and liberated by the embryo was sought in the culture media of human embryos using two bioassays. The first bioassay demonstrated the existence of a thrombocytopaenic factor after the i.p. injection of culture media into splenectomized mice. This factor was found more frequently in media which contained an embryo compared to those which contained a non-fertilized oocyte. PAF-acether (1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) was searched for with a specific bioassay, using washed rabbit platelets. This remained negative for all the media studied, including those which had contained an embryo giving rise to a pregnancy. In these experiments it was not possible to relate embryo-derived platelet activating factor (EDPAF) to PAF-acether. Neither were we able to use the detection of EDPAF to test embryonic viability, or attempt to identify those embryos which were susceptible to lead to a pregnancy after intrauterine transfer from among all the embryos transferred. [ABSTRACT FROM PUBLISHER]

Spleen cells from male (CBA/N × DBA/2) F1 hybrid mice do not significantly respond to in vitro stimulation by trinitrophenyl-conjugated polyacrylamide beads (TNP-PAA), whereas the same antigen elicits high PFC responses in female F I hybrid cells. Therefore, this antigen could be classified as a T-independent type 2 (TI-2) antigen. When male spleen cells were co-stimulated by TNP-PAA and TI type 1 antigen, either LPS or Brucella abortus, they produced vigorous anti-TNP responses. A similar increase of the in vitro responsiveness of male F1 hybrid spleen cells to TNP-PAA antigen was provoked by the addition of supernatants from P 388-DI cells stimulated by muramyl-dipeptide (MDP) mainly containing interleukin-1 (IL-1) or supernatants from phorbol 12-myristate 13-acetate (PMA)-stimulated EL-4 calls that contained T-cell factors. The PFC response to another TI-2 antigen, TNP-Ficoll, was also significantly enhanced after co-stimulation by P 388-DI supernatants. The response to TI-2 antigens being macrophage dependent, the influence of supernatants of peritoneal macrophages from male and female F1 hybrids incubated with TNP-Ficoll on the PFC response of normal DBA/2 mouse spleen cells to sheep erythrocytes was assessed. It was found that macrophage supernatants from female hybrids regularly increased by more than two times this anti- SRBC PFC response, whereas macrophage supernatants from male F1 hybrids did not. Moreover, in a specific proliferation test measuring IL-1 activity, when macrophage supernatants from female F1 produced a 13-fold increase of thymidine incorporation, supernatants from male F1 only produced a three-fold increase. It is concluded that, in addition to the known defects of B cells from Xid mice, their macrophages arc also defective. [ABSTRACT FROM AUTHOR]

In recent years, melatonin has been increasingly used in hospital settings for the treatment of sleep disorders in older patients, despite many barriers: restriction by ANSM, non-approval to healthcare facility use, and non-reimbursement. In order to describe the use of melatonin in older hospitalized patients, a survey was conducted between February and May 2022, with hospital pharmacists working in geriatric care units in France. Overall, 35 interviews were conducted with hospital pharmacists: 30 dispensed melatonin, with marketed prolonged-release melatonin medications (n = 30), and/or with immediate-release magistral or hospital preparations (n = 11). The conducted survey highlighted the criteria for using the different forms of melatonin, but also the disparities in terms of supply and management within the different establishments. Given the increasing use of melatonin in hospital settings and in order to guarantee the same accessibility to hospital teams and to patients on discharge from the hospital, a reassessment by the authorities of the melatonin-based medication status seems necessary in the light of the new available data.

Persistent manifestations of COVID-19, known as «long COVID» or post-COVID-19 condition (RA02, CIM-11), affect many infected individuals, with a 24-month prevalence depending on the studies context (18 % in a recent Swiss study). The diversity of clinical presentation, the sometimes complex diagnostic methods, and the multidisciplinary management highlight the importance of a holistic approach, with practical advice for assessing work capacity in the outpatient setting. This article offers an update and synthesis of current knowledge concerning post-COVID-19 condition with practical recommendations for primary care medicine, illustrated by real clinical situations., Competing Interests: Les auteurs remercient le Pr Jacques Cornuz pour sa contribution et la relecture de cet article.

Background: There is a high prevalence of somatoform disorders and medically unexplained symptoms. When it comes to deciding whether a patient is able to work, it is essential to differentiate a somatoform disorder from a factitious disorder. The case presented demonstrates the impact on disability benefits and the subsequent psychosocial repercussions of misdiagnosing between a factitious disorder and a somatoform disorder., Case Presentation: A 42-year-old Caucasian woman worked as a 100% fiduciary accountant until the age of 32 when she was placed on medical leave due to persistent trigeminal neuralgia. Afterward, she developed total blindness, not explained by a physiological process, accompanied by distress in a crucial emotional context. We evaluated the patient for a revision of a disability income after a diagnosis of factitious disorder with severe consequences such as disability income suspension and family conflict. Our psychiatric examination concluded the diagnoses of pain disorders related to psychological factors and a dissociative neurological symptom disorder with visual disturbance., Conclusions: Blindness not explained by a physiological process may accompany trauma and psychological distress. Differentiating this pathology from factitious disorder or simulation is essential from an insurance medicine point of view, but also for its treatment., (© 2023. The Author(s).)

Long COVID, frequently associated to neuropsychiatric manifestations, impacts the ability of patients to return to work and often requires adjustments of the previous workstation. Due to the duration of the symptoms and the professional consequences, disability insurance (DI) procedures may be necessary. Because the persistent symptoms of Long COVID are often subjective and unspecific, the medical report to the DI should include a detailed description of the functional impact of these manifestations., Competing Interests: les auteurs n’ont déclaré aucun conflit d’intérêt en relation avec cet article.

During meiosis, programmed double-strand breaks are repaired by homologous recombination (HR) to form crossovers that are essential to homologous chromosome segregation. Single-stranded DNA (ssDNA) containing intermediates are key features of HR, which must be highly regulated. RPA, the ubiquitous ssDNA binding complex, was thought to play similar roles during mitotic and meiotic HR until the recent discovery of MEIOB and its partner, SPATA22, two essential meiosis-specific proteins. Here, we show that like MEIOB, SPATA22 resembles RPA subunits and binds ssDNA. We studied the physical and functional interactions existing between MEIOB, SPATA22, and RPA, and show that MEIOB and SPATA22 interact with the preformed RPA complex through their interacting domain and condense RPA-coated ssDNA in vitro. In meiotic cells, we show that MEIOB and SPATA22 modify the immunodetection of the two large subunits of RPA. Given these results, we propose that MEIOB-SPATA22 and RPA form a functional ssDNA-interacting complex to satisfy meiotic HR requirements by providing specific properties to the ssDNA., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objectives : Little information is available on the characteristics of elderly patients starting TNFα antagonist treatment for rheumatoid arthritis (RA). The objective of this work was to compare prescription patterns in RA patients younger vs. older than 75 years. Methods : Biologic-naive patients with active RA (DAS28 > 3.2) despite first-line therapy were included between 2007 and 2009 in the prospective, multicentre, longitudinal, observational, population-based CORPUS-RA cohort. TNFα antagonist users were defined as having received at least one TNFα antagonist during the first study year. The groups < 75 years and ≥ 75 years were compared regarding comorbidities, inflammation (CRP and ESR), disease activity (DAS28), disability (HAQ-DI), number of physician visits, and treatment. To verify the impact of the cut off, we also compared patients aged 70 years or more to patients younger than 70 years. Results : Of 543 RA patients, 382 had complete one-year follow-up data, including 114 TNFα antagonist users, 3 (6%) among the 49 patients aged 75 years or over and 111 (32%) of the 333 patients younger than 75 years (p < 0.01). Disease activity in the two age groups was similar at inclusion and after one year. Comorbidities and a history of auto-immunity were more common in the older group. Compared to their younger counterparts, the older patients received glucocorticoids more often (p = 0.003) and synthetic disease-modifying anti-rheumatic drugs less often (p = 0.01). Conclusion : TNFα antagonists are used less often and glucocorticoids more often in elderly patients with active RA compared to their younger counterparts. The fact that this study was performed in 2007-9 is a limitation in terms of relevance to today's patients and further studies should be conducted in new cohorts of active RA.

Objective: In this study, we looked for a new family of latency reversing agents., Design: We searched for G-protein-coupled receptors (GPCR) coexpressed with the C-C chemokine receptor type 5 (CCR5) in primary CD4 T cells that activate infected cells and boost HIV production., Methods: GPCR coexpression was unveiled by reverse transcriptase-PCR. We used fluorescence resonance energy transfer to analyze the dimerization with CCR5 of the expressed GPCR. Viral entry was measured by flow cytometry, reverse transcription by quantitative PCR, nuclear factor-kappa B translocation by immunofluorescence, long terminal repeat activation using a gene reporter assay and viral production by p24 quantification., Results: Gαi-coupled sphingosine-1-phophate receptor 1 (S1P1) is highly coexpressed with CCR5 on primary CD4 T cells and dimerizes with it. The presence of S1P1 had major effects neither on viral entry nor on reverse transcription. Yet, S1P1 signaling induced NFκB activation, boosting the expression of the HIV LTR. Consequently, in culture medium containing sphingosine-1-phophate, the presence of S1P1 enhanced the replication of a CCR5-, but also of a CXCR4-using HIV-1 strain. The S1P1 ligand FTY720, a drug used in multiple sclerosis treatment, inhibited HIV-1 productive infection of monocyte-derived dendritic cells and of severe combined immunodeficiency mice engrafted with human peripheral blood mononuclear cells. Conversely, S1P1 agonists were able to force latently infected peripheral blood mononuclear cells and lymph node cells to produce virions in vitro., Conclusion: Altogether these data indicate that the presence of S1P1 facilitates HIV-1 replicative cycle by boosting viral genome transcription, S1P1 antagonists have anti-HIV effects and S1P1 agonists are HIV latency reversing agents.