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1.
Value Health ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38977188

RESUMEN

OBJECTIVES: To analyze worldwide sales of new therapeutic agents and to estimate the time it takes for product sales to exceed industry-wide average drug development costs. METHODS: Data obtained from company reports were analyzed to track worldwide sales of new medicines approved by the US Food and Drug Administration from 1995 to 2014. All sales figures were reported in 2019 US dollars. Kaplan-Meier curves were used to evaluate the time it took for discounted product sales to exceed the average costs associated with developing one new drug (accounting for the costs of failed trials), using published estimates of these costs. RESULTS: Based on data for 361 of 558 new therapeutic agents approved over the study period (median follow-up: 13.2 years), mean sales revenue per product was $15.2 billion through the end of 2019; the median was $6.7 billion. These products jointly generated global sales of $5.5 trillion since approval. Revenues were highly skewed, with the 25 best selling products (7%, 25/361) accounting for 38% of this amount ($2.1 trillion/$5.5 trillion). About 47% of products had discounted sales that exceeded the estimated industry-wide average costs of development within 5 years of approval, and 75% within 10 years. After attributing potential production, marketing, and other costs, these numbers dropped to 21% of products within 5 years of approval, and 46% within 10 years. CONCLUSIONS: Sales of new medicines approved from 1995 to 2014 were highly skewed, but a majority of products had net discounted sales that exceeded the industry-wide average costs of development within 10 years of approval. An understanding of how sales revenues accrue in the years after initial approval, alongside data on business costs, can inform discussions about how to incentivize private investment in innovation while ensuring affordable prices for patients and the health-care system.

2.
bioRxiv ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38979171

RESUMEN

Many expectant mothers use CBD to alleviate symptoms like nausea, insomnia, anxiety, and pain, despite limited research on its long-term effects. However, CBD passes through the placenta, affecting fetal development and impacting offspring behavior. We investigated how prenatal CBD exposure affects the insular cortex (IC), a brain region involved in emotional processing and linked to psychiatric disorders. The IC is divided into two territories: the anterior IC (aIC), processing socioemotional signals, and the posterior IC (pIC), specializing in interoception and pain perception. Pyramidal neurons in the aIC and pIC exhibit sex-specific electrophysiological properties, including variations in excitability and the excitatory/inhibitory balance. We investigated IC's cellular properties and synaptic strength in the offspring of both sexes from mice exposed to low-dose CBD during gestation (E5-E18; 3mg/kg, s.c.). Prenatal CBD exposure induced sex-specific and territory-specific changes in the active and passive membrane properties, as well as intrinsic excitability and the excitatory/inhibitory balance, in the IC of adult offspring. The data indicate that in-utero CBD exposure disrupts IC neuronal development, leading to a loss of functional distinction between IC territories. These findings may have significant implications for understanding the effects of CBD on emotional behaviors in offspring.

3.
ACS Omega ; 9(26): 28385-28396, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38973847

RESUMEN

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.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39042830

RESUMEN

Microencapsulation is an advanced methodology for the protection, preservation, and/or delivery of active materials in a wide range of industrial sectors, such as pharmaceuticals, cosmetics, fragrances, paints, coatings, detergents, food products, and agrochemicals. Polymeric materials have been extensively used as microcapsule shells to provide appropriate barrier properties to achieve controlled release of the encapsulated active ingredient. However, significant limitations are associated with such capsules, including undesired leaching and the nonbiodegradable nature of the typically used polymers. In addition, the energy cost of manufacturing microcapsules is an important factor to be considered when designing microcapsule systems and the corresponding production processes. Recent factors linked to UN sustainability goals are modifying how such microencapsulation systems should be designed in pursuit of "ideal" microcapsules that are efficient, safe, cost-effective and environmentally friendly. This review provides an overview of advances in microencapsulation, with emphasis on sustainable microcapsule designs. The key evaluation techniques to assess the biodegradability of microcapsules, in compliance with recently evolving European Union requirements, are also described. Moreover, the most common methodologies for the fabrication of microcapsules are presented within the framework of their energy demand. Recent promising microcapsule designs are also highlighted for their suitability toward meeting current design requirements and stringent regulations, tackling the ongoing challenges, limitations, and opportunities.

5.
ArXiv ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39070038

RESUMEN

Human ability to recognize complex visual patterns arises through transformations performed by successive areas in the ventral visual cortex. Deep neural networks trained end-to-end for object recognition approach human capabilities, and offer the best descriptions to date of neural responses in the late stages of the hierarchy. But these networks provide a poor account of the early stages, compared to traditional hand-engineered models, or models optimized for coding efficiency or prediction. Moreover, the gradient backpropagation used in end-to-end learning is generally considered to be biologically implausible. Here, we overcome both of these limitations by developing a bottom-up self-supervised training methodology that operates independently on successive layers. Specifically, we maximize feature similarity between pairs of locally-deformed natural image patches, while decorrelating features across patches sampled from other images. Crucially, the deformation amplitudes are adjusted proportionally to receptive field sizes in each layer, thus matching the task complexity to the capacity at each stage of processing. In comparison with architecture-matched versions of previous models, we demonstrate that our layerwise complexity-matched learning (LCL) formulation produces a two-stage model (LCL-V2) that is better aligned with selectivity properties and neural activity in primate area V2. We demonstrate that the complexity-matched learning paradigm is responsible for much of the emergence of the improved biological alignment. Finally, when the two-stage model is used as a fixed front-end for a deep network trained to perform object recognition, the resultant model (LCL-V2Net) is significantly better than standard end-to-end self-supervised, supervised, and adversarially-trained models in terms of generalization to out-of-distribution tasks and alignment with human behavior.

6.
Artículo en Inglés | MEDLINE | ID: mdl-39074527

RESUMEN

Fragile X Syndrome (FXS) stands out as a prominent cause of inherited intellectual disability and a prevalent disorder closely linked to autism. FXS is characterized by substantial alterations in social behavior, encompassing social withdrawal, avoidance of eye contact, heightened social anxiety, increased arousal levels, language deficits, and challenges in regulating emotions. Conventional behavioral assessments primarily focus on short-term interactions within controlled settings. In this study, we conducted a comprehensive examination of the adaptive group behavior of Fmr1 KO male mice over a three-day period, without introducing experimental interventions or task-based evaluations. The data unveiled intricate behavioral anomalies, with the most significant changes manifesting during the initial adaptation to unfamiliar environments. Notably, certain behaviors exhibited a gradual return to typical patterns over time. This dynamic Fmr1 KO phenotype exhibited heightened activity, featuring increased exploration, amplified social interest, and an unconventional approach to social interactions characterized by a higher frequency of shorter engagements. These findings contribute to the growing understanding of social behavior in individuals with FXS and underscore the significance of comprehending their adaptive responses in various environmental contexts.

7.
S Afr J Surg ; 62(2): 68, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38838124

RESUMEN

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.


Asunto(s)
Carcinoma Ductal Pancreático , Hospitales de Enseñanza , Cuidados Paliativos , Neoplasias Pancreáticas , Mejoramiento de la Calidad , Humanos , Sudáfrica , Masculino , Femenino , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/mortalidad , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/mortalidad , Persona de Mediana Edad , Anciano , Derivación y Consulta , Calidad de Vida , Auditoría Médica , Continuidad de la Atención al Paciente , Grupos Focales , Toma de Decisiones Conjunta
9.
J Manag Care Spec Pharm ; : 1-11, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38905356

RESUMEN

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.

10.
J Vis ; 24(6): 12, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38884544

RESUMEN

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.


Asunto(s)
Macaca mulatta , Estimulación Luminosa , Corteza Visual , Animales , Corteza Visual/fisiología , Estimulación Luminosa/métodos , Percepción Visual/fisiología , Masculino , Orientación/fisiología , Neuronas/fisiología
11.
J Neurosci ; 44(30)2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38830765

RESUMEN

Fragile X syndrome (FXS) is a genetic cause of intellectual disability and autism spectrum disorder. The mesocorticolimbic system, which includes the prefrontal cortex (PFC), basolateral amygdala (BLA), and nucleus accumbens core (NAcC), is essential for regulating socioemotional 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 SPN 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 fragile X messenger ribonucleoprotein 1 (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.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Síndrome del Cromosoma X Frágil , Núcleo Accumbens , Animales , Síndrome del Cromosoma X Frágil/fisiopatología , Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/genética , Ratones , Masculino , Núcleo Accumbens/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Vías Nerviosas/fisiopatología , Optogenética , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiopatología , Ratones Endogámicos C57BL , Complejo Nuclear Basolateral/metabolismo , Complejo Nuclear Basolateral/fisiopatología , Ratones Noqueados , Neuronas/metabolismo , Neuronas/fisiología , Plasticidad Neuronal/fisiología
12.
Am J Bot ; 111(6): e16352, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38853465

RESUMEN

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.


Asunto(s)
Filogenia , Bosques , Evolución Biológica
13.
Int J Cancer ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38922879

RESUMEN

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.

14.
Front Behav Neurosci ; 18: 1399716, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38835838

RESUMEN

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.

17.
Biol Sex Differ ; 15(1): 29, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561860

RESUMEN

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.


Asunto(s)
Corteza Cerebral , Corteza Insular , Ratones , Animales , Femenino , Masculino , Corteza Cerebral/fisiología , Neuronas
18.
bioRxiv ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38645268

RESUMEN

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.

19.
Mol Biol Rep ; 51(1): 438, 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520482

RESUMEN

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.


Asunto(s)
Juglans , Humanos , Juglans/genética , Polimorfismo Genético , Repeticiones de Microsatélite/genética , Semillas , Frutas/genética
20.
Opt Express ; 32(5): 7463-7472, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439425

RESUMEN

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.

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