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: Supporting youth projects: youth work in the face of constraints
No full textInternational audienceIn a context where policies aimed at ‘youth participation’ are being stepped up, youth workers are tasked to support ‘youth projects’. The findings of the interview survey on which this article is based show that youth work consists in managing institutional constraints while developing strategies focusing on youth centre attendance. It is within this tension that the (real) meaning of the profession emerges, through the appropriation of registers from which they give meaning to the job.Dans un contexte de renforcement des politiques visant la « participation des jeunes », les animatrices et animateurs jeunesse sont chargés d’accompagner les « projets de jeunes ». L’enquête par entretiens sur laquelle s’appuie cet article montre que le métier consiste à tenir à distance ces prescriptions institutionnelles et à développer des stratégies dont l’enjeu est la fréquentation des locaux. C’est dans cette tension qu’émerge le sens du métier à travers l’appropriation de registres à partir desquels ils et elles donnent sens au métier
Are olfactory stimuli able to induce emotional responses in a positive context in ewes?
No full textInternational audienceThe perception of olfactory stimuli can influence animal emotions and behaviors, which are critical for survival and adaptation. This study explored the properties of threeolfactory stimuli (orange essential oil, wolf feces, and cadaverine) to induce emotion in sheep, in a non-stressful environment enriched with social and food resources. Contrary to expectations, wolf feces, while repellent, did not trigger overt stress behaviors such as increased vocalizations or agitation. Similarly, orange essential oil did not elicit strong positive valence responses, suggesting that the positive experimental context may mask its effect. Interestingly, cadaverine, typically associated with body decomposition, has no impact on sheep behaviors except that is induced emetic responses in two individuals, indicating potential disgust. Overall, this research highlights the complex interplay between social, food, and environmental factors in shaping the emotional responses of sheep to olfactory stimuli, underscoring the importance of context and individual variability. These findings contribute to a better understanding of olfactory influences on animal welfare and behavior
L’apport des sous-écosystèmes et lieux totems dans l’animation d’écosystèmes entrepreneuriaux
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In Vitro Evaluation of the Efficacy of 27 French Over-the-Counter Anti-lice Treatments
No full textInternational audienceHead lice remain a major public health problem worldwide, with a high prevalence among schoolchildren. Many lice treatments are available, but their efficacy is often poorly evaluated. An increase in the resistance of parasites to neurotoxic therapies, combined with a partial efficacy of certain suffocating agents, can contribute to the maintenance or even rise in infestations. The study aims to evaluate the effectiveness of 27 different over-the-counter lice treatments available in France in 2024 for eliminating lice and nits. To do this, we used the subspecies Pediculus humanus humanus, a well-established model organism for competitive studies. The products were purchased in France from randomly selected pharmacies and then tested in the laboratory on lice and their eggs. The laboratory conditions of the in vitro tests were designed to reproduce the exposure times and application methods recommended by the manufacturers. A parallel study was carried out on sales data for anti-lice products from French pharmacies. The results allowed the classification of the 27 products into four groups: five products demonstrated potentially 100% pediculicidal and ovicidal activity; four products showed potentially 100% pediculicidal activity but insufficient ovicidal activity; another four products exhibited potentially 100% ovicidal activity but insufficient pediculicidal activity; and the remaining 14 products showed insufficient activity against both lice and nits. Sales data show that only 27% of products sold in French pharmacies are able to completely cure pediculosis. The French market for lice products is mainly occupied by treatments with a lack of effectiveness. Health authorities should require thorough efficacy assessments before registration and conduct periodic reviews to ensure the effectiveness of these treatments sold in pharmacies
Impact of educational interventions provided to patients with a central venous catheter and their informal caregivers: a systematic review
No full textInternational audienceBackground: Central venous catheters offer considerable benefits, but their presence can expose patients to serious complications. Preventing such complications is crucial, not only for individual patients, but also for hospitals and the healthcare system. Objective: To assess the impact of educational interventions on clinical and non-clinical outcomes provided to patients with central venous catheters and/or their informal caregivers, regardless of the therapeutic indication, and to define the specific characteristics of effective educational strategies. Methods: Medline and Embase were searched, covering all publications since their inception to 13 August 2024. Articles on clinical and/or non-clinical outcomes related to the education of patients with central venous catheters and their informal caregivers were included. Studies focusing solely on the education of healthcare providers were excluded. The reference lists of included studies were hand searched for additional citations. This systematic review followed PRISMA guidelines and the protocol was registered in PROSPERO (CRD42024577193). The quality of the included studies was assessed using the Mixed Methods Appraisal Tool. Results: In total, 20 articles, representing 974 patients and 875 informal caregivers, were included in the review: seven randomized trials, ten quantitative studies without randomization, and three descriptive quantitative studies. The compliance rate of 60% for the randomised trials determined using the Mixed Methods Appraisal Tool indicates a low risk of bias, whereas non-randomised and descriptive quantitative studies show more methodological weaknesses (40% and 45%, respectively). There was a positive trend, significant or not, for the impact of patient education on reducing complications, particularly those related to infection (85% of the studies concerned by this outcome). This was often observed (64%) in studies based on educational interventions repeated over time. Studies that showed a significant improvement in patients’ knowledge and skills in terms of self-management showed beneficial results in terms of the occurrence of complications. Nurses were the most common educators (15/20), and the most frequently used tools were written materials and digital resources, often combined with other methods for greater effectiveness. Conclusions: This systematic review encourages the implementation of educational interventions for patients with central venous catheters and their informal caregivers, notably to decrease infections. Providing them with written documents and digital tools, and delivering them repeatedly over time, should be promoted. However, study heterogeneity limits definitive conclusions. Future research should standardize methodologies, involve patients in intervention design, and assess cost-effectiveness to ensure sustainable implementation
Défense au fond et prétention
No full textInternational audience(Civ. 2e, 16 janv. 2025, no 22-17.956, publié au Bulletin ; D. actu. 4 févr. 2025, obs. M. Barba ; D. 2025. 505, obs. N. Fricero ; JCP 2025. 252, note J. Théron ; Gaz. Pal. 18 mars 2025, note J.-B. Meyrier ; ibid. 15 avr. 2025, p. 65, obs. L. Mayer ; LEDB 2025, no 3, p. 7, obs. M. Mignot ; Com. 6 nov. 2024, no 23-19.957, JCP 2025. 457, no 7, obs. P. Simler
State of the art on the understanding of plasma jet interaction with skin tissue models (invited review)
No full textInternational audienceThis paper provides an overview of past and new experimental studies with kHz helium plasma jets and floating-electrode dielectric barrier discharge (DBD) in the context of biomedical applications with the aim to discuss the interaction of plasma jet with skin tissue models. The key motivation is to summarize and address perspectives on the understanding of the mode of action of nonthermal plasma from surface delivery to the biological response of deeper and deeper tissues. First, the significant impact of the target exposed to the plasma jet on the plasma characteristics is documented, highlighting the importance of considering this interaction for in vivo studies. Next, cell permeabilization was first reported and translated to the study of plasma jet permeation of reconstructed epidermis, human explants, and human tissues. Strong analogies are observed in all three substrates, demonstrating a potent but transient modulation of surface features and skin barrier function for a few minutes following a brief plasma exposure time of a few tens of seconds. Interestingly, the modulation of reactive oxygen and nitrogen species generation, so-called RONS, with the variation of the pulse repetition rate of the plasma jet shows no direct correlation with the permeation efficiency. This questions the role of RONS alone in the mode of action of nonthermal plasma for biological response in the few hundreds of microns to the few millimeter tissue layers as was previously also questioned for subcutaneous action of plasma in wound and tumor in vivo treatments. Finally, the combinative role of RONS with electrical factors (charging, current, electric field) is hypothesized and supported with the investigation of deeper living skin tissue oxygenation and vasodilation
Relaxation-Based In Vivo Discrimination of Oxidized and Reduced States of a Redox-Switchable <sup>19</sup>F MRI Probe
No full textInternational audienceMRI assessment of the tissue redox state is important for revealing and understanding various pathologies, and redox responsive imaging probes capable of generating discrete and quantifiable signals both in their reduced and oxidized forms can provide enhanced detection reliability. The small fluorinated, redox-active FeL1 chelate is a prototype of such agents. L1 forms stable and inert complexes with both Fe2+ and Fe3+ions, and the redox potential of the Fe3+ L1/Fe2+L1 couple (+240 mV vs. NHE) is adapted to biological redox sensing. Fe2+L1 undergoes instantaneous oxidation in the presence of H2O2, and Fe3+L1 is reduced by cysteine, glutathione and ascorbate. Fe2+L1 and Fe3+L1 have very different proton relaxivities (0.1 mM -1 s -1 and 2.83 mM -1 s -1 , respectively, 60 MHz, 298 K), as well as 19F relaxation times (T1 = 71-130 ms; T2 = 60-117 ms and T1 = 2.43 ms; T2 = 1.81 ms, respectively, 400 MHz, 298 K), in accordance with the different paramagnetic relaxation enhancement capacity of the two iron redox states. Upon applying specific MRI pulse sequences adapted to the relaxation rate (RARE for Fe2+L1 and UTE for Fe3+L1, combined with appropriate acquisition parameters), both redox forms are detected in 19F MR phantom images with good sensitivity and signal-to-noise ratios linearly dependent on probe concentration. Fe2+L1 and Fe3+L1 can be readily visualized and unambiguously discriminated based on their 19 F relaxation times in living mice, following intramuscular injection. The possibility to monitor the redox switch in 1 H MRI as well is an additional advantage of this bioresponsive probe
Trafficking of luteinizing hormone receptor directs the differential signal activation between luteinizing hormone and chorionic gonadotropin
No full textInternational audienceLuteinizing hormone (LH) and human choriogonadotropin (hCG) support distinct reproductive events via differential activation of the luteinizing hormone receptor (LHCGR). LH-mediated LHCGR trafficking is known to be key in activating and regulating its signal responses, yet whether LH and hCG differentially direct LHCGR trafficking is unknown. Bioluminescence resonance energy transfer (BRET) trafficking biosensors and highresolution TIRF imaging demonstrated that LH induces rapid internalization and recycling via an APPL1linked very early endosomal pathway, while hCG-mediated receptor trafficking and recycling is slower, and preferentially involves beta-arrestins and accumulation in endocytic compartments positive for early and late endosomal markers. Receptor internalization was differentially required for Gq, Gi and Gs protein-mediated signals, revealing distinct LH- vs hCG-trafficking signatures that may be fundamental to preserving unique hormone signalling patterns and their impact at the genomic level. This study supports different LH vs hCG modes of action on the LHCGR through differential post-endocytic sorting of the receptor, providing a potential 'location bias' mechanism underlying the distinct physiological roles of these two gonadotropins. Short title: LH vs hCG receptor internalization
Polyphenisms in the reproductive response of male quail to short days are driven by testosterone-independent uncoupling in the photoperiodic TSH-DIO2/DIO3 pathway
No full textInternational audienceThe neuroendocrine control of seasonal breeding in vertebrates depends upon a TSH/DIO2-3 pathway located in the medio-basal hypothalamus. In male quail, early data demonstrated that this photoperiodic control is independent of testosterone. At least two strong predictions arise from this. First, testosterone is unlikely to exert any significant feedback upon the expression of Tshb/Dio2/Dio3. Second, in situations where photoperiod is invariable but reproductive output differs amongst individuals, differential expression of Tshb and/or Dio2/Dio3 may be expected. Here, we validate these two predictions. First, using castration/implantation in male quails maintained under a long photoperiod, we show that the expression of Tshb/Dio2/Dio3 is testosterone independent, while aggressiveness and cognitive behaviours are testosterone driven. Second, taking advantage of the large inter-individual variability in the response of the gonadal axis to short days (i.e. phenotypic morphs), we demonstrate that the magnitude of the decrease in testes mass, size of the cloacal gland and testosterone plasma level is positively associated with levels of induction of Dio3 and repression of Dio2. In contrast, a uniformly low expression of Tshb expression is found in all morphs. These data provide strong evidence that the TSH/DIO2-3 pathway governs the reproductive axis in male quail independently of testosterone. Furthermore, our findings are consistent with the notion that substantial uncoupling in the photoperiodic TSH/DIO2-3 pathway is responsible for the reproductive polyphenisms