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1.
ACS Omega ; 9(26): 28385-28396, 2024 Jul 02.
Article de Anglais | MEDLINE | ID: mdl-38973847

RÉSUMÉ

Commercial perfume microcapsules are becoming popular across the globe to fulfill consumers' demands. However, most of microcapsules rely on synthetic polymers and/or animal-sourced ingredients to form the shells. Therefore, replacement of the shell materials is imperative to minimize environmental microplastic pollution, as well as to meeting peoples' needs, religious beliefs, and lifestyles. Herein, we report a methodology to fabricate environmentally benign dual-shell (fungal chitosan-SiO2) microcapsules laden with fragrance oil (hexyl salicylate). Anionically stabilized oil droplets were coated with fungal chitosan via interfacial electrostatic interactions at pH 2, which were then covered by an inorganic coating of SiO2 produced via external alkaline mineralization of sodium silicate. Core-shell microcapsules with a spherical morphology were achieved. Under compression, dual-shell chitosan-SiO2 microcapsules yielded a mean nominal rupture stress of 3.0 ± 0.2 MPa, which was significantly higher than that of single-shell microcapsules (1.7 ± 0.2 MPa). After 20 days in neutral pH water, only ∼2.5% of the oil was released from dual-shell microcapsules, while single-shell microcapsules cumulatively released more than 10%. These findings showed that the additional SiO2 coating significantly enhanced both mechanical and barrier properties of microcapsules, which may be appealing for multiple commercial applications, including cosmetics and detergents.

2.
Front Behav Neurosci ; 18: 1399716, 2024.
Article de Anglais | MEDLINE | ID: mdl-38835838

RÉSUMÉ

Introduction: In order to successfully move from place to place, our brain often combines sensory inputs from various sources by dynamically weighting spatial cues according to their reliability and relevance for a given task. Two of the most important cues in navigation are the spatial arrangement of landmarks in the environment, and the continuous path integration of travelled distances and changes in direction. Several studies have shown that Bayesian integration of cues provides a good explanation for navigation in environments dominated by small numbers of easily identifiable landmarks. However, it remains largely unclear how cues are combined in more complex environments. Methods: To investigate how humans process and combine landmarks and path integration in complex environments, we conducted a series of triangle completion experiments in virtual reality, in which we varied the number of landmarks from an open steppe to a dense forest, thus going beyond the spatially simple environments that have been studied in the past. We analysed spatial behaviour at both the population and individual level with linear regression models and developed a computational model, based on maximum likelihood estimation (MLE), to infer the underlying combination of cues. Results: Overall homing performance was optimal in an environment containing three landmarks arranged around the goal location. With more than three landmarks, individual differences between participants in the use of cues are striking. For some, the addition of landmarks does not worsen their performance, whereas for others it seems to impair their use of landmark information. Discussion: It appears that navigation success in complex environments depends on the ability to identify the correct clearing around the goal location, suggesting that some participants may not be able to see the forest for the trees.

3.
J Vis ; 24(6): 12, 2024 Jun 03.
Article de Anglais | MEDLINE | ID: mdl-38884544

RÉSUMÉ

Neural population activity in sensory cortex informs our perceptual interpretation of the environment. Oftentimes, this population activity will support multiple alternative interpretations. The larger the spread of probability over different alternatives, the more uncertain the selected perceptual interpretation. We test the hypothesis that the reliability of perceptual interpretations can be revealed through simple transformations of sensory population activity. We recorded V1 population activity in fixating macaques while presenting oriented stimuli under different levels of nuisance variability and signal strength. We developed a decoding procedure to infer from V1 activity the most likely stimulus orientation as well as the certainty of this estimate. Our analysis shows that response magnitude, response dispersion, and variability in response gain all offer useful proxies for orientation certainty. Of these three metrics, the last one has the strongest association with the decoder's uncertainty estimates. These results clarify that the nature of neural population activity in sensory cortex provides downstream circuits with multiple options to assess the reliability of perceptual interpretations.


Sujet(s)
Macaca mulatta , Stimulation lumineuse , Cortex visuel , Animaux , Cortex visuel/physiologie , Stimulation lumineuse/méthodes , Perception visuelle/physiologie , Mâle , Orientation/physiologie , Neurones/physiologie
4.
J Neurosci ; 2024 Jun 03.
Article de Anglais | MEDLINE | ID: mdl-38830765

RÉSUMÉ

Fragile X syndrome (FXS) is a genetic cause of intellectual disability and autism spectrum disorder (ASD), associated with social deficits. The mesocorticolimbic system, which includes the prefrontal cortex (PFC), basolateral amygdala (BLA), and nucleus accumbens core (NAcC), is essential for regulating socio-emotional behaviors. We employed optogenetics to compare the functional properties of the BLA→NAcC, PFC→NAcC, and reciprocal PFC↔BLA pathways in Fmr1-/y::Drd1a-tdTomato male mice. In FXS mice, the PFC↔BLA reciprocal pathway was unaffected, while significant synaptic modifications occurred in the BLA/PFC→NAcC pathways. We observed distinct changes in D1 striatal projection neurons (SPNs) and separate modifications in D2 SPNs. In FXS mice, the BLA/PFC→NAcC-D2 SPNs pathways demonstrated heightened synaptic strength. Focusing on the BLA→NAcC pathway, linked to autistic symptoms, we found increased AMPAR and NMDAR currents, and elevated spine density in D2 SPNs. Conversely, the amplified firing probability of BLA→NAcC-D1 SPNs was not accompanied by increased synaptic strength, AMPAR and NMDAR currents, or spine density. These pathway-specific alterations resulted in an overall enhancement of excitatory-to-spike coupling, a physiologically relevant index of how efficiently excitatory inputs drive neuronal firing, in both BLA→NAcC-D1 and BLA→NAcC-D2 pathways. Finally, the absence of FMRP led to impaired long-term depression specifically in BLA→D1 SPNs. These distinct alterations in synaptic transmission and plasticity within circuits targeting the NAcC highlight the potential role of postsynaptic mechanisms in selected SPNs in the observed circuit-level changes. This research underscores the heightened vulnerability of the NAcC in the context of FMRP deficiency, emphasizing its pivotal role in the pathophysiology of FXS.Significance Statement Fragile X Syndrome is a neurodevelopmental disorder characterized by significant emotional dysregulation and social challenges. The mesocorticolimbic system is a key socioemotional regulator. Nevertheless, its functioning in this condition is still poorly understood. Our study investigates connections between the basolateral amygdala (BLA), prefrontal cortex (PFC), and nucleus accumbens core (NAcC). We observed that while the PFC↔BLA reciprocal connections remained unaffected, their projections onto the NAcC showed target cell-specific changes. Specifically, D2 SPNs exhibited increased synaptic transmission and spine density, whereas D1 SPNs showed heightened firing probability and impaired long-term depression, alongside enhanced neuronal firing efficiency in both SPN types. These findings emphasize the NAcC's crucial role as a neurobiological substrate in the pathophysiology of Fragile X Syndrome.

5.
S Afr J Surg ; 62(2): 68, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38838124

RÉSUMÉ

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with poor survival rates. Timeously introduced palliative care (PC) improves the quality of life (QoL) for patients with terminal diseases. In 2020, an in-patient PC-quality improvement (QI) programme was implemented for PDAC patients. This study compared PC outcomes before and after the introduction of the PC-QI programme. METHODS: A focus group identified five critical intervention areas that could improve care. These were in-patient PC referral, pain and symptom control, shared decision-making, interdisciplinary collaborative care, and continuity of care. A hospital record audit of PDAC patients was conducted in pre- and post-implementation cohorts, and the results were compared. RESULTS: A total of 68 (2017 pre-PC-QI) and 39 (2022 post-PC-QI) patient records were audited. Demography, symptom duration, referral delay, and clinical findings were similar in both cohorts. In-patient PC referrals improved significantly from 54.4% in 2017 to 82.1% in 2022 (p = 0.0059). Significant improvements were also recorded in shared decisionmaking, collaboration, and continuity of care, while the reassessment of pain and symptoms after treatment improved. Fewer invasive procedures were done in the 2022 cohort (p = 0.0056). The delay from admission to an invasive diagnostic procedure decreased from a mean of 8.7 to 1.5 days (p = 0.0001). The duration of hospital admission, overall survival (OS), and readmissions during the final 30 days of life were similar. CONCLUSION: The QI programme resulted in improved use of the in-hospital PC service and made better use of scarce resources. Increasing patient and family participation and feedback will further inform the development of the quality of PC services.


Sujet(s)
Carcinome du canal pancréatique , Hôpitaux d'enseignement , Soins palliatifs , Tumeurs du pancréas , Amélioration de la qualité , Humains , République d'Afrique du Sud , Mâle , Femelle , Carcinome du canal pancréatique/thérapie , Carcinome du canal pancréatique/mortalité , Tumeurs du pancréas/thérapie , Tumeurs du pancréas/mortalité , Adulte d'âge moyen , Sujet âgé , Orientation vers un spécialiste , Qualité de vie , Audit médical , Continuité des soins , Groupes de discussion , Prise de décision partagée
6.
Am J Bot ; : e16352, 2024 Jun 09.
Article de Anglais | MEDLINE | ID: mdl-38853465

RÉSUMÉ

PREMISE: Phylogenetic approaches can provide valuable insights on how and when a biome emerged and developed using its structuring species. In this context, Brachystegia Benth, a dominant genus of trees in miombo woodlands, appears as a key witness of the history of the largest woodland and savanna biome of Africa. METHODS: We reconstructed the evolutionary history of the genus using targeted-enrichment sequencing on 60 Brachystegia specimens for a nearly complete species sampling. Phylogenomic inferences used supermatrix (RAxML-NG) and summary-method (ASTRAL-III) approaches. Conflicts between species and gene trees were assessed, and the phylogeny was time-calibrated in BEAST. Introgression between species was explored using Phylonet. RESULTS: The phylogenies were globally congruent regardless of the method used. Most of the species were recovered as monophyletic, unlike previous plastid phylogenetic reconstructions where lineages were shared among geographically close individuals independently of species identity. Still, most of the individual gene trees had low levels of phylogenetic information and, when informative, were mostly in conflict with the reconstructed species trees. These results suggest incomplete lineage sorting and/or reticulate evolution, which was supported by network analyses. The BEAST analysis supported a Pliocene origin for current Brachystegia lineages, with most of the diversification events dated to the Pliocene-Pleistocene. CONCLUSIONS: These results suggest a recent origin of species of the miombo, congruently with their spatial expansion documented from plastid data. Brachystegia species appear to behave potentially as a syngameon, a group of interfertile but still relatively well-delineated species, an aspect that deserves further investigations.

7.
J Manag Care Spec Pharm ; : 1-11, 2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38905356

RÉSUMÉ

BACKGROUND: The Centers for Medicare and Medicaid Services (CMS) are currently negotiating prices with pharmaceutical manufacturers for the first 10 Part D drugs selected for Medicare drug price negotiation. Non-publicly available data, including the net prices of selected drugs and their therapeutic alternatives, will play a central role in the determination of the maximum fair prices (MFPs). OBJECTIVE: To estimate price benchmarks involved in the derivation of the starting point of the CMS initial price offer for the 10 drugs selected for Medicare price negotiation. METHODS: For the 10 drugs selected for negotiation, we reported (1) the list price, (2) the net price after manufacturer discounts, (3) the maximum negotiated price based on the minimum statutory discount, and (4) the ceiling of the MFP, estimated as the lowest of the latter 2. We also estimated net prices for therapeutic alternatives to the selected drugs. Net prices were estimated using peer-reviewed methodology that isolates commercial discounts negotiated between payers and manufacturers from mandatory discounts under government programs. All price benchmarks were estimated at the product level, for 30-day equivalent dosing, using 2021 data. RESULTS: 6 products (apixaban, rivaroxaban, empagliflozin, sacubitril/valsartan, etanercept, and insulin aspart) had therapeutic alternatives with lower net prices, which will be integrated with clinical benefit data in the derivation of initial price offers. The other 4 products (ustekinumab, ibrutinib, sitagliptin, and dapagliflozin) had therapeutic alternatives with higher net prices than the drugs selected for negotiation. For ibrutinib and ustekinumab, prices based on the minimum discounts were considerably lower than the estimated net prices and will likely set the starting point of the initial price offer. For dapagliflozin and sitagliptin, the starting point of the initial price offer will likely resemble their existing net prices. CONCLUSIONS: Our analyses identify different negotiation scenarios for the first 10 drugs selected for Medicare price negotiation, based on key elements involved in the derivation of the initial price offer. Our analyses can help improve transparency in the negotiation process, because the CMS is not required to reveal the information used in the derivation of price offers.

8.
Int J Cancer ; 2024 Jun 24.
Article de Anglais | MEDLINE | ID: mdl-38922879

RÉSUMÉ

Previous studies demonstrated limited efficacy of immune checkpoint inhibitors in unresectable acral melanoma (AM); it remains unclear how this translates to the adjuvant setting. This study investigates clinical outcomes of acral compared to cutaneous melanoma (CM) patients treated with adjuvant anti-PD-1 after complete resection. All stages III-IV AM and CM patients receiving adjuvant anti-PD-1 after complete resection between 2018 and 2022 were included from the prospective nationwide Dutch Melanoma Treatment Registry. We analyzed recurrence-free survival (RFS), distant metastasis-free survival (DMFS), and overall survival (OS). A multivariable Cox regression analysis of RFS was performed to adjust for potential confounders. We included 1958 (86 AM and 1872 CM) patients. At baseline, AM patients more frequently had KIT mutations, higher disease stages, and Eastern Cooperative Oncology Group Performance Status, and fewer BRAF and NRAS mutations. Median RFS was 14.8 months (95% confidence interval [CI]: 11.5-29.3) in AM and 37.4 months (95% CI: 34.6 to not reached) in CM (p = .002). After correcting for potential confounders, AM remained associated with a higher risk of recurrence (HRadj 1.53; 95% CI: 1.07-2.17; p = .019). Two-year DMFS tended to be worse for AM than for CM: 64.5% versus 79.7% (p = .050). Two-year OS was significantly lower in AM (71.5% vs. 84.3%; p = .027). The results of this study suggest a poorer outcome of adjuvant-treated AM compared to CM. Studies assessing the added value of adjuvant treatment in AM are needed. Future research should investigate alternative treatment strategies to improve outcomes of high-risk AM.

12.
Biol Sex Differ ; 15(1): 29, 2024 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-38561860

RÉSUMÉ

BACKGROUND: The insular cortex (IC) plays a pivotal role in processing interoceptive and emotional information, offering insights into sex differences in behavior and cognition. The IC comprises two distinct subregions: the anterior insular cortex (aIC), that processes emotional and social signals, and the posterior insular cortex (pIC), specialized in interoception and perception of pain. Pyramidal projection neurons within the IC integrate multimodal sensory inputs, influencing behavior and cognition. Despite previous research focusing on neuronal connectivity and transcriptomics, there has been a gap in understanding pyramidal neurons characteristics across subregions and between sexes. METHODS: Adult male and female C57Bl/6J mice were sacrificed and tissue containing the IC was collected for ex vivo slice electrophysiology recordings that examined baseline sex differences in synaptic plasticity and transmission within aIC and pIC subregions. RESULTS: Clear differences emerged between aIC and pIC neurons in both males and females: aIC neurons exhibited distinctive features such as larger size, increased hyperpolarization, and a higher rheobase compared to their pIC counterparts. Furthermore, we observed variations in neuronal excitability linked to sex, with male pIC neurons displaying a greater level of excitability than their female counterparts. We also identified region-specific differences in excitatory and inhibitory synaptic activity and the balance between excitation and inhibition in both male and female mice. Adult females demonstrated greater synaptic strength and maximum response in the aIC compared to the pIC. Lastly, synaptic long-term potentiation occurred in both subregions in males but was specific to the aIC in females. CONCLUSIONS: We conclude that there are sex differences in synaptic plasticity and excitatory transmission in IC subregions, and that distinct properties of IC pyramidal neurons between sexes could contribute to differences in behavior and cognition between males and females.


This study investigates differences in the insular cortex (IC), a region of the brain responsible for emotions and sensory perceptions, between male and female mice. The IC has two parts: the front (aIC) deals with emotions and social cues, while the back (pIC) is focused on sensing pain and bodily sensations. We examined specific brain cells called pyramidal neurons in both aIC and pIC and discovered noteworthy distinctions between these neurons in adult male and female mice. Firstly, aIC neurons were larger and had unique electrical properties in both male and female mice. Males had more excitable pIC neurons compared to females, indicating that their neurons were more likely to transmit signals. We also explored how these neurons communicate with each other through connections known as synapses. In adult females, the aIC had stronger connections than the pIC. Finally, we observed that specific types of basic synaptic learning occurred exclusively in males in the aIC. These findings underscore significant disparities in the IC between males and females, offering valuable insights into the potential reasons behind variations in behaviors and emotions between sexes.


Sujet(s)
Cortex cérébral , Cortex insulaire , Souris , Animaux , Femelle , Mâle , Cortex cérébral/physiologie , Neurones
13.
bioRxiv ; 2024 May 23.
Article de Anglais | MEDLINE | ID: mdl-38645268

RÉSUMÉ

Genomic data collected from viral outbreaks can be exploited to reconstruct the dispersal history of viral lineages in a two-dimensional space using continuous phylogeographic inference. These spatially explicit reconstructions can subsequently be used to estimate dispersal metrics allowing to unveil the dispersal dynamics and evaluate the capacity to spread among hosts. Heterogeneous sampling intensity of genomic sequences can however impact the accuracy of dispersal insights gained through phylogeographic inference. In our study, we implement a simulation framework to evaluate the robustness of three dispersal metrics - a lineage dispersal velocity, a diffusion coefficient, and an isolation-by-distance signal metric - to the sampling effort. Our results reveal that both the diffusion coefficient and isolation-by-distance signal metrics appear to be robust to the number of samples considered for the phylogeographic reconstruction. We then use these two dispersal metrics to compare the dispersal pattern and capacity of various viruses spreading in animal populations. Our comparative analysis reveals a broad range of isolation-by-distance patterns and diffusion coefficients mostly reflecting the dispersal capacity of the main infected host species but also, in some cases, the likely signature of rapid and/or long-distance dispersal events driven by human-mediated movements through animal trade. Overall, our study provides key recommendations for the lineage dispersal metrics to consider in future studies and illustrates their application to compare the spread of viruses in various settings.

14.
Opt Express ; 32(5): 7463-7472, 2024 Feb 26.
Article de Anglais | MEDLINE | ID: mdl-38439425

RÉSUMÉ

We study theoretically and demonstrate experimentally a 16-band narrow band wavelength selective filter in the near-infrared range. The combination of a pair of distributed Bragg reflectors with a sub-wavelength grating metasurface embedded in the intra-cavity provides a narrow response which can be tuned by adjusting the geometry of the sub-wavelength grating metasurface. The key advantage of this approach is its ease of fabrication, where the spectral response is tuned by merely changing the grating period, resulting in a perfectly planar geometry that can be easily integrated with a broad variety of photodetectors, thus enabling attractive applications such as bio-imaging, time-of-flight sensors and LiDAR. The experimental results are supported by numerical simulations and effective medium theory that unveil the mechanisms that lead to the optical response of the device. It is also shown how the polarization dependence of the structure can be used to determine very accurately the polarization of incoming light.

15.
Mol Biol Rep ; 51(1): 438, 2024 Mar 23.
Article de Anglais | MEDLINE | ID: mdl-38520482

RÉSUMÉ

PREMISE OF THE STUDY: Coula edulis Baill (Coulaceae) is a common tree species in the Guineo-Congolian forests producing an edible fruit known as African walnut, which is an important food and income resource for rural populations. However, the species suffers from a deficit of natural regeneration. We developed here nuclear microsatellite markers for C. edulis to be able to study the genetic structure of its natural populations and gene flow. METHODS AND RESULTS: A genomic library was obtained using the Illumina platform, and 21 polymorphic microsatellite loci were developed. The polymorphic microsatellites displayed eight to 22 alleles per locus (average: 14.2), with a mean expected heterozygosity ranging from 0.33 to 0.72 in five populations from Central and West Africa. CONCLUSIONS: The high polymorphism of the nuclear microsatellite markers developed makes them useful to investigate gene flow and the organization of genetic diversity in C. edulis, and to assess whether particular genetic resources require conservation efforts.


Sujet(s)
Juglans , Humains , Juglans/génétique , Polymorphisme génétique , Répétitions microsatellites/génétique , Graines , Fruit/génétique
16.
EClinicalMedicine ; 69: 102485, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38370537

RÉSUMÉ

Background: The prognosis of advanced melanoma patients has significantly improved over the years. We aimed to evaluate the survival per year of diagnosis. Methods: All systemically treated patients diagnosed with advanced melanoma from 2013 to 2021 were included from the Dutch Melanoma Treatment Registry. Baseline characteristics and overall survival (OS) were compared between the different years of diagnosis. A multivariable Cox proportional hazards model was used to estimate the association between year of diagnosis and OS. Findings: For this cohort study, we included 6260 systemically treated advanced melanoma patients. At baseline, there was an increase over the years in age, the percentage of patients with an ECOG PS ≥ 2, with brain metastases, and a synchronous diagnosis of primary and unresectable melanoma. Median OS increased from 11.2 months (95% CI 10.0-12.4) for patients diagnosed in 2013 to 32.0 months (95% CI 26.6-36.7) for patients diagnosed in 2019. Median OS was remarkably lower for patients diagnosed in 2020 (26.6 months; 95% CI 23.9-35.1) and 2021 (24.0 months; 95% CI 20.4-NR). Patients diagnosed in 2020 and 2021 had a higher hazard of death compared to patients diagnosed in 2019, although this was not significant. The multivariable Cox regression showed a lower hazard of death for the years of diagnosis after 2013. In contrast, patients diagnosed in 2020 and 2021 had a higher hazard of death compared to patients diagnosed in 2019. Interpretation: After a continuous survival improvement for advanced melanoma patients between 2013 and 2019, outcomes of patients diagnosed in 2020 and 2021 seem poorer. This trend of decreased survival remained after correcting for known prognostic factors and previous neoadjuvant or adjuvant treatment, suggesting that it is explained by unmeasured factors, which-considering the timing-could be COVID-19-related. Funding: For the Dutch Melanoma Treatment Registry (DMTR), the Dutch Institute for Clinical Auditing foundation received a start-up grant from governmental organization The Netherlands Organization for Health Research and Development (ZonMW, project number 836002002). The DMTR is structurally funded by Bristol-Myers Squibb, Merck Sharpe & Dohme, Novartis, and Roche Pharma. Roche Pharma stopped funding in 2019, and Pierre Fabre started funding the DMTR in 2019. For this work, no funding was granted.

17.
Ecol Evol ; 14(2): e10953, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38371858

RÉSUMÉ

Helichrysum arenarium (L.) Moench (Asteraceae) is a self-compatible, insect-pollinated herb occurring in sand grasslands, and is declining and endangered in many parts of its European distribution range. A recovery plan of H. arenarium has been conducted in southern Belgium, involving plant translocations. We developed multiplex genotyping protocol for nine microsatellite markers previously published for Helichrysum italicum and two newly developed microsatellite markers for H. arenarium. Eleven polymorphic loci were associated (pooled) in two multiplex panels, to assess the genetic status of the only small remaining population in Belgium and of three large German populations used as seed source for propagating transplants. The small Belgian population was characterized by high clonality, with only two, however heterozygous, genets detected. The three large German populations showed high genetic diversity (H e ranging from 0.635 to 0.670) and no significant inbreeding coefficient values, despite expectations of geitonogamous selfing. Management practices (grazing livestock) increasing seed dispersal distances, inbreeding depression at early stages of development, and mechanisms preventing or delaying selfing might be hypothesized to explain the observed patterns. The two Belgian genotypes remained within genetic variation range of German populations so that the high genetic differentiation between Belgian and German populations (F ST values ranging from 0.186 to 0.206) likely resulted from genetic drift effects and small sample size. Transplants obtained from seeds sampled from the three large source populations from Germany constitute a highly diverse, noninbred gene pool, and are thus of high genetic quality for plant translocations.

18.
Biol Sex Differ ; 15(1): 18, 2024 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-38383408

RÉSUMÉ

BACKGROUND: Pup-dam ultrasonic vocalizations (USVs) are essential to cognitive and socio-emotional development. In autism and Fragile X Syndrome (FXS), disruptions in pup-dam USV communication hint at a possible connection between abnormal early developmental USV communication and the later emergence of communication and social deficits. METHODS: Here, we gathered USVs from PND 10 FXS pups during a short period of separation from their mothers, encompassing animals of all possible genotypes and both sexes (i.e., Fmr1-/y vs. Fmr1+/y males and Fmr1+/+, +/-, and -/- females). This allowed comparing the influence of sex and gene dosage on pups' communication capabilities. Leveraging DeepSqueak and analyzing vocal patterns, intricate vocal behaviors such as call structure, duration, frequency modulation, and temporal patterns were examined. Furthermore, homing behavior was assessed as a sensitive indicator of early cognitive development and social discrimination. This behavior relies on the use of olfactory and thermal cues to navigate and search for the maternal or nest odor in the surrounding space. RESULTS: The results show that FMRP-deficient pups of both sexes display an increased inclination to vocalize when separated from their mothers, and this behavior is accompanied by significant sex-specific changes in the main features of their USVs as well as in body weight. Analysis of the vocal repertoire and syntactic usage revealed that Fmr1 gene silencing primarily alters the USVs' qualitative composition in males. Moreover, sex-specific effects of Fmr1 silencing on locomotor activity and homing behavior were observed. FMRP deficiency in females increased activity, reduced nest-reaching time, and extended nest time. In males, it prolonged nest-reaching time and reduced nest time without affecting locomotion. CONCLUSIONS: These findings highlight the interplay between Fmr1 gene dosage and sex in influencing communicative and cognitive skills during infancy.


In this study, we investigated ultrasonic vocalizations (USVs) and homing behavior in a mouse model of Fragile X Syndrome (FXS), a leading genetic cause of autism spectrum disorder (ASD) caused by a mutation of the X-chromosome linked Fmr1 gene. Disruptions in pup-dam USV communication and cognitive skills may be linked to the later emergence of communication and social deficits in ASD. USVs were collected from 10-day-old FXS pups of all possible genotypes and both sexes during a short period of separation from their mothers. We utilized DeepSqueak, an advanced deep learning system, to examine vocal patterns and intricate vocal behaviors, including call structure, duration, frequency modulation, and their temporal patterns. Homing, a sensitive indicator of early cognitive development and social discrimination was assessed at P13. The results showed that FXS pups of both sexes displayed an increased inclination to vocalize when separated from their mothers. Examination of the vocal repertoire and its syntactic usage revealed that the silencing of the Fmr1 gene primarily alters the qualitative composition of ultrasonic communication in males. The sex-specific changes observed in USVs were accompanied by modifications in body weight. Regarding homing behavior, the deficiency of FMRP led to opposite deficits in activity, time to reach the nest, and nesting time depending on sex. Taken together, these findings highlight the interplay between Fmr1 gene dosage and sex in shaping communication and cognition during infancy.


Sujet(s)
Syndrome du chromosome X fragile , Animaux , Souris , Femelle , Mâle , Syndrome du chromosome X fragile/génétique , Syndrome du chromosome X fragile/psychologie , Vocalisation animale , Souris knockout , Protéine du syndrome X fragile/génétique , Cognition , Dosage génique , Modèles animaux de maladie humaine
19.
JAMA Intern Med ; 184(3): 328-330, 2024 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-38285561

RÉSUMÉ

This cohort study analyzes review times and approval outcomes of health technology assessments conducted in 6 high-income countries for novel therapeutic agents approved by the US Food and Drug Administration.


Sujet(s)
Agrément de médicaments , Évaluation de la technologie biomédicale , Humains , États-Unis , Pays développés , Food and Drug Administration (USA)
20.
Nat Commun ; 15(1): 817, 2024 Jan 27.
Article de Anglais | MEDLINE | ID: mdl-38280859

RÉSUMÉ

Animals have evolved mechanisms to travel safely and efficiently within different habitats. On a journey in dense terrains animals avoid collisions and cross narrow passages while controlling an overall course. Multiple hypotheses target how animals solve challenges faced during such travel. Here we show that a single mechanism enables safe and efficient travel. We developed a robot inspired by insects. It has remarkable capabilities to travel in dense terrain, avoiding collisions, crossing gaps and selecting safe passages. These capabilities are accomplished by a neuromorphic network steering the robot toward regions of low apparent motion. Our system leverages knowledge about vision processing and obstacle avoidance in insects. Our results demonstrate how insects might safely travel through diverse habitats. We anticipate our system to be a working hypothesis to study insects' travels in dense terrains. Furthermore, it illustrates that we can design novel hardware systems by understanding the underlying mechanisms driving behaviour.


Sujet(s)
Vision , Perception visuelle , Animaux , Insectes , Déplacement
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