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1.
Clin Ophthalmol ; 18: 1933-1944, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38983598

RESUMO

Purpose: To assess the refractive and visual outcomes of hyperopic and astigmatic eyes implanted with a monofocal, aspheric, bitoric intraocular lens (IOL) with plate haptics following cataract surgery. Methods: The study evaluated 51 eyes implanted with the AT TORBI 709M IOL (Carl Zeiss Meditec AG, Jena, Germany) during a follow-up of 12-months. Refractive error, rotational stability, monocular uncorrected distance visual acuity (UDVA), monocular corrected distance visual acuity (CDVA), and contrast sensitivity were analyzed at 1-, 6-, and 12-months post-surgery. Results: At 12 months, the cumulative CDVA was 20/25 in 94.12% of eyes and 20/32 or better in 98.04%. The UDVA was the same as, or better than, the CDVA in 88.24% of eyes. The mean logMAR UDVA and CDVA values were 0.06 ± 0.11 and 0.00 ± 0.08, respectively. In addition, 92.16% of eyes were within ±0.50 D and 98.04% were within ±1.00 D of a spherical equivalent, and 86.27% of eyes had refractive astigmatism ≤0.50D and 100% were ≤1.00D. The mean spherical equivalent was 0.21 ± 0.31D and the mean refractive cylinder 0.34 ± 0.27D. The IOL rotation was 1.18 ± 1.35 degrees and all eyes had a rotation ≤5 degrees. The log contrast sensitivity functions were good and similar for all spatial frequencies during follow-up. Conclusion: Our results demonstrate that implantation of the AT TORBI 709M IOL in hyperopic and astigmatic eyes is effective and safe. The visual and refractive outcomes were good, showing excellent rotational stability.

2.
Bioconjug Chem ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958375

RESUMO

Conventional serum markers often fail to accurately detect cholestasis accompanying many liver diseases. Although elevation in serum bile acid (BA) levels sensitively reflects impaired hepatobiliary function, other factors altering BA pool size and enterohepatic circulation can affect these levels. To develop fluorescent probes for extracorporeal noninvasive hepatobiliary function assessment by real-time monitoring methods, 1,3-dipolar cycloaddition reactions were used to conjugate near-infrared (NIR) fluorochromes with azide-functionalized BA derivatives (BAD). The resulting compounds (NIRBADs) were chromatographically (FC and PTLC) purified (>95%) and characterized by fluorimetry, 1H NMR, and HRMS using ESI ionization coupled to quadrupole TOF mass analysis. Transport studies using CHO cells stably expressing the BA carrier NTCP were performed by flow cytometry. Extracorporeal fluorescence was detected in anesthetized rats by high-resolution imaging analysis. Three NIRBADs were synthesized by conjugating alkynocyanine 718 with cholic acid (CA) at the COOH group via an ester (NIRBAD-1) or amide (NIRBAD-3) spacer, or at the 3α-position by a triazole link (NIRBAD-2). NIRBADs were efficiently taken up by cells expressing NTCP, which was inhibited by taurocholic acid (TCA). Following i.v. administration of NIRBAD-3 to rats, liver uptake and consequent release of NIR fluorescence could be extracorporeally monitored. This transient organ-specific handling contrasted with the absence of release to the intestine of alkynocyanine 718 and the lack of hepatotropism observed with other probes, such as indocyanine green. NIRBAD-3 administration did not alter serum biomarkers of hepatic and renal toxicity. NIRBADs can serve as probes to evaluate hepatobiliary function by noninvasive extracorporeal methods.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38981101

RESUMO

Organometallic molecules are promising for molecular electronic devices due to their potential to improve electrical conductance through access to complex orbital covalency that is not available to light-element organic molecules. However, studies of the formation of organometallic monolayers and their charge transport properties are scarce. Here, we report the cluster formation and charge transport properties of gold-triarylbismuthane-gold molecular junctions. We found that triarylbismuthane molecules with -CN anchoring groups form clusters during the creation of self-assembled submonolayers. This clustering is attributed to strong interactions between the bismuth (Bi) center and the nitrogen atom in the -CN group of adjacent molecules. Examination of the influence of -NH2 and -CN anchoring groups on junction conductance revealed that, despite a stronger binding energy between the -NH2 group and gold, the conductance per molecular unit (i.e., molecule for the -NH2 group and cluster for the -CN group) is higher with the -CN anchoring group. Further analysis showed that an increase in the number of -CN groups from one to three within the junctions leads to a decrease in conductance while increasing the size of the cluster. This demonstrates the significant effects of different anchoring groups and the impact of varying the number of -CN groups on both the charge transport and cluster formation. This study highlights the importance of selecting the appropriate anchoring group in the design of molecular junctions. Additionally, controlling the size and formation of clusters can be a strategic approach to engineering charge transport in molecular junctions.

4.
BMC Microbiol ; 24(1): 247, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971740

RESUMO

BACKGROUND: Mercury (Hg) is highly toxic and has the potential to cause severe health problems for humans and foraging animals when transported into edible plant parts. Soil rhizobia that form symbiosis with legumes may possess mechanisms to prevent heavy metal translocation from roots to shoots in plants by exporting metals from nodules or compartmentalizing metal ions inside nodules. Horizontal gene transfer has potential to confer immediate de novo adaptations to stress. We used comparative genomics of high quality de novo assemblies to identify structural differences in the genomes of nitrogen-fixing rhizobia that were isolated from a mercury (Hg) mine site that show high variation in their tolerance to Hg. RESULTS: Our analyses identified multiple structurally conserved merA homologs in the genomes of Sinorhizobium medicae and Rhizobium leguminosarum but only the strains that possessed a Mer operon exhibited 10-fold increased tolerance to Hg. RNAseq analysis revealed nearly all genes in the Mer operon were significantly up-regulated in response to Hg stress in free-living conditions and in nodules. In both free-living and nodule environments, we found the Hg-tolerant strains with a Mer operon exhibited the fewest number of differentially expressed genes (DEGs) in the genome, indicating a rapid and efficient detoxification of Hg from the cells that reduced general stress responses to the Hg-treatment. Expression changes in S. medicae while in bacteroids showed that both rhizobia strain and host-plant tolerance affected the number of DEGs. Aside from Mer operon genes, nif genes which are involved in nitrogenase activity in S. medicae showed significant up-regulation in the most Hg-tolerant strain while inside the most Hg-accumulating host-plant. Transfer of a plasmid containing the Mer operon from the most tolerant strain to low-tolerant strains resulted in an immediate increase in Hg tolerance, indicating that the Mer operon is able to confer hyper tolerance to Hg. CONCLUSIONS: Mer operons have not been previously reported in nitrogen-fixing rhizobia. This study demonstrates a pivotal role of the Mer operon in effective mercury detoxification and hypertolerance in nitrogen-fixing rhizobia. This finding has major implications not only for soil bioremediation, but also host plants growing in mercury contaminated soils.


Assuntos
Transferência Genética Horizontal , Mercúrio , Óperon , Simbiose , Transcriptoma , Mercúrio/metabolismo , Mercúrio/toxicidade , Bactérias Fixadoras de Nitrogênio/genética , Bactérias Fixadoras de Nitrogênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Fixação de Nitrogênio , Rhizobium leguminosarum/genética , Rhizobium leguminosarum/metabolismo , Microbiologia do Solo
5.
J Clin Med ; 13(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38892758

RESUMO

Objectives: Both diabetes mellitus (DM) and gynaecological and colorectal cancers are highly prevalent diseases. Furthermore, the presence of DM constitutes a risk factor and poor prognostic indicator for these types of cancer. This study is based on the European Health Interview Surveys in Spain (EHISS) of 2014 and 2020. It aimed to determine the trends in adherence to screening tests for gynaecological cancers (breast and cervical) and colorectal cancer, compare adherence levels between populations with and without diabetes, and identify predictors of adherence in the population with diabetes. Methods: An epidemiological case-control study based on the EHISS data of 2014 and 2020 was conducted. The characteristics of participants who underwent screening tests were analysed based on the presence or absence of DM, and predictors of adherence to these preventive activities were identified. Results: A total of 1852 participants with reported DM and 1852 controls without DM, adjusted for age and sex, were included. A higher adherence to mammography was observed in women without diabetes compared to those with diabetes, although statistical significance was not reached (72.9% vs. 68.6%, p = 0.068). Similarly, higher Pap smear adherence was observed in the population without diabetes in the age group between 60 and 69 years compared to the population with diabetes (54.0% vs. 45.8%, p = 0.016). Pap smear adherence among women with diabetes was significantly higher in the EHISS of 2020 (52.0% in 2014 vs. 61.0% in 2020, p = 0.010), as was the case for faecal occult blood testing (13.8% in 2014 vs. 33.8% in 2020, p < 0.001), but it was not significant for mammography (70.4% in 2014 vs. 66.8% in 2020, p = 0.301). Overall, the predictors of adherence to screening tests were older age, history of cancer and higher education level. Conclusions: Adherence levels to cancer screening tests were lower in the population with diabetes compared to those without diabetes, although an improvement in Pap smear and faecal occult blood test adherence was observed in 2020 compared to 2014. Understanding predictors is important to improve adherence rates in the population with diabetes.

6.
Materials (Basel) ; 17(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893791

RESUMO

Elastic composites were prepared using a procedure involving hot plates and zinc powder that was directly dispersed into an EVA matrix. The correlation between the zinc content and the conductive properties of the material was studied via impedance spectroscopy, the thermal properties of the material were studied via differential calorimetry and the mechanical properties of the composites were studied via tensile strength curves, representing an important advancement in the characterization of this type of composite material. The composites' tensile strength and elongation at break decrease with the addition of filler since zinc particles act as stress-concentrating centres, while the composites' hardness and Young's modulus increase because of an increase in the stiffness of the material. The AC perturbation across the EVA/Zn composites was characterized using an RC parallel equivalent circuit that allowed us to easily measure their resistivity (ρp) and permittivity (εp). The dependence of these electrical magnitudes on the zinc content is correlated with their mechanical properties across the characteristic time constant τp = ρp·Îµp of this equivalent circuit. The dependence of the mechanical and electrical magnitudes on the zinc content is consistent with the formation of percolation clusters. The addition of graphite particles increases their potential performance. Three possible mechanisms for the electrical transport of the ac-perturbation across the EVA/Zn composites have been identified. Chemical corrosion in acid media causes the loss of zinc surface particles, but their bulk physical properties practically remain constant.

8.
Sensors (Basel) ; 24(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38894283

RESUMO

Permanent engravings on contact lenses provide information about the manufacturing process and lens positioning when they are placed on the eye. The inspection of their morphological characteristics is important, since they can affect the user's comfort and deposit adhesion. Therefore, an inverted wavefront holoscope (a lensless microscope based on Gabor's principle of in-line digital holography) is explored for the characterization of the permanent marks of soft contact lenses. The device, based on an in-line transmission configuration, uses a partially coherent laser source to illuminate the soft contact lens placed in a cuvette filled with a saline solution for lens preservation. Holograms were recorded on a digital sensor and reconstructed by back propagation to the image plane based on the angular spectrum method. In addition, a phase-retrieval algorithm was used to enhance the quality of the recovered images. The instrument was experimentally validated through a calibration process in terms of spatial resolution and thickness estimation, showing values that perfectly agree with those that were theoretically expected. Finally, phase maps of different engravings for three commercial soft contact lenses were successfully reconstructed, validating the inverted wavefront holoscope as a potential instrument for the characterization of the permanent marks of soft contact lenses. To improve the final image quality of reconstructions, the geometry of lenses should be considered to avoid induced aberration effects.

9.
Sensors (Basel) ; 24(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38894296

RESUMO

Jump height tests are employed to measure lower-limb muscle power of athletic and non-athletic populations. The most popular instruments for this purpose are jump mats and, in recent years, smartphone apps, which compute jump height through the manual annotation of video recordings and recently automatically using the sound produced during the jump to extract the flight time. In a previous work, the afore-mentioned sound systems were presented by the authors in which the take-off and landing events from the audio recordings of jump executions were obtained using classical signal processing. In this work, a more precise, noise-immune, and robust system, capable of working in the most unfavorable environments, is presented. The system uses a deep neural network trained specifically for this purpose. More than 300 jumps were recorded to train and validate the network performance. The ground truth was a jump mat, providing a slightly better accuracy in quiet and medium quiet environments but excellent accuracy in noisy and complicated ones. The developed audio-based system is a trustworthy instrument for measuring jump height accurately in any kind of environment, providing a perfect measurement tool that can be accessed through a mobile phone in the form of an app.


Assuntos
Redes Neurais de Computação , Humanos , Som , Aplicativos Móveis , Smartphone , Esportes/fisiologia , Masculino , Força Muscular/fisiologia
10.
Neurooncol Adv ; 6(1): vdae058, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887507

RESUMO

Background: The progression of vestibular schwannoma (VS) is intricately linked with interactions between schwannoma cells and the extracellular matrix. Surgical resection of VS is associated with substantial risks as tumors are adherent to the brainstem and cranial nerves. We evaluate the role of matrix metalloproteinase 9 (MMP9) in VS and explore its potential as a biomarker to classify adherent VS. Methods: Transcriptomic analysis of a murine schwannoma allograft model and immunohistochemical analysis of 17 human VS were performed. MMP9 abundance was assessed in mouse and human schwannoma cell lines. Transwell studies were performed to evaluate the effect of MMP9 on schwannoma invasion in vitro. Plasma biomarkers were identified from a multiplexed proteomic analysis in 45 prospective VS patients and validated in primary culture. The therapeutic efficacy of MMP9 inhibition was evaluated in a mouse schwannoma model. Results: MMP9 was the most highly upregulated protease in mouse schwannomas and was significantly enriched in adherent VS, particularly around tumor vasculature. High levels of MMP9 were found in plasma of patients with adherent VS. MMP9 outperformed clinical and radiographic variables to classify adherent VS with outstanding discriminatory ability. Human schwannoma cells secreted MMP9 in response to TNF-α which promoted cellular invasion and adhesion protein expression in vitro. Lastly, MMP9 inhibition decreased mouse schwannoma growth in vivo. Conclusions: We identify MMP9 as a preoperative biomarker to classify adherent VS. MMP9 may represent a new therapeutic target in adherent VS associated with poor surgical outcomes that lack other viable treatment options.

11.
Cir Cir ; 92(3): 298-306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38862113

RESUMO

OBJECTIVE: To evaluate if the comorbidity and coinfections presented by SARS-CoV-2 infection vs. COVID-19 impact our Mexican children. METHOD: Prospective and observational study that included the 2020-2021 peak influenza season. All patients with a diagnosis of infection by SARS-CoV-2 vs. COVID-19 who were admitted to the Hospital Infantil de Mexico were analyzed. Real-time RT-PCR for SARS-CoV-2 was performed in all patients, determining E, RdRp and RP genes and protein N, as well as RT-PCR for detection of respiratory viruses. RESULTS: The inclusion criteria were met by 163 patients. The group with the highest risk of becoming ill was adolescents (40.4%), followed by schoolchildren and preschoolers (21.4% and 19.6% of the cases, respectively). There were three cases with viral coinfection: two (1.2%) with parvovirus B-19 and one (0.6%) with herpes type I; another two (1.2%) showed bacterial coinfection. The main comorbidity were obesity, acute lymphoblastic leukemia and arterial hypertension. Regarding mortality, we only had four cases (2.4%). CONCLUSIONS: Obesity, cancer, hypertension, heart disease and diabetes are comorbidity present in our patients, as referred to in literature, but not coinfections. In our study, we did not have any associated mortality related to comorbidity.


OBJETIVO: Evaluar el impacto de la comorbilidad y de las coinfecciones presentadas por la infección por SARS-CoV-2 vs. COVID-19 en niños mexicanos. MÉTODO: Estudio prospectivo y observacional que comprendió la temporada alta de influenza 2020-2021, analizando todos los pacientes con diagnóstico de infección vs. enfermedad por SARS-CoV-2 vs. COVID-19 que ingresaron al Hospital Infantil de México. Se realizó en todos RT-PCR en tiempo real para SARS-CoV-2, determinando gen E, gen RdRp, gen RP y proteína N, y RT-PCR multiplex para detección de virus respiratorios. RESULTADOS: Los criterios de inclusión los cumplieron 163 pacientes. El grupo con mayor riesgo de enfermar fueron los adolescentes (40.4%), seguidos de los escolares y preescolares (21.4% y 19.6% de los casos, respectivamente). Hubo tres casos con coinfección viral: dos (1.2%) con parvovirus B-19 y uno (0.6%) con herpes tipo I; hubo otros dos (1.2%) con coinfección bacteriana. La principal comorbilidad correspondió a obesidad, leucemia linfoblástica aguda e hipertensión arterial. En cuanto a mortalidad, solo hubo cuatro casos (2.4%). CONCLUSIONES: Obesidad, cáncer, hipertensión, cardiopatías y diabetes constituyen la comorbilidad en nuestros pacientes, como se refiere en la literatura, no así las coinfecciones. En nuestro estudio no hubo casos de mortalidad relacionada con la comorbilidad.


Assuntos
COVID-19 , Coinfecção , Comorbidade , Influenza Humana , Humanos , COVID-19/epidemiologia , Coinfecção/epidemiologia , Criança , Pré-Escolar , Masculino , Estudos Prospectivos , Feminino , Adolescente , México/epidemiologia , Influenza Humana/epidemiologia , Hipertensão/epidemiologia , Hipertensão/complicações , Lactente , Estações do Ano , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Infecções Bacterianas/epidemiologia
12.
Cancer Immunol Res ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916567

RESUMO

Poor response to Bacillus Calmette-Guérin (BCG) immunotherapy remains a major barrier in the management of patients with non-muscle invasive bladder cancer (NMIBC). Multiple factors are associated with poor outcomes, including biological aging and female sex. More recently, it has emerged that a B-cell infiltrated pre-treatment immune microenvironment of NMIBC tumors can influence the response to intra-vesically administered BCG. The mechanisms underlying the roles of B cells in NMIBC are poorly understood. Here, we show that B-cell dominant tertiary lymphoid structures (TLSs), a hallmark feature of the chronic mucosal immune response, are abundant and located close to the epithelial compartment in pre-treatment tumors from BCG non-responders. Digital spatial proteomic profiling of whole tumor sections from male and female patients with NMIBC who underwent treatment with intravesical BCG, revealed higher expression of immune exhaustion-associated proteins within the tumor-adjacent TLSs in both responders and non-responders. Chronic local inflammation, induced by the N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) carcinogen, led to TLS formation with recruitment and differentiation of the immunosuppressive atypical B-cell (ABC) subset within the bladder microenvironment, predominantly in aging female mice compared to their male counterparts. Depletion of ABCs simultaneous to BCG treatment delayed cancer progression in female mice. Our findings provide evidence indicating a role for ABCs in BCG response and will inform future development of therapies targeting the B cell-exhaustion axis.

13.
Int J Biol Macromol ; 273(Pt 2): 132956, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38848838

RESUMO

Free-standing films have been obtained by drop-casting cellulose-glycerol mixtures (up to 50 wt% glycerol) dissolved in trifluoroacetic acid and trifluoroacetic anhydride (TFA:TFAA, 2:1, v:v). A comprehensive examination of the optical, structural, mechanical, thermal, hydrodynamic, barrier, migration, greaseproof, and biodegradation characteristics of the films was conducted. The resulting cellulose-glycerol blends exhibited an amorphous molecular structure and a reinforced H-bond network, as evidenced by X-ray diffraction analysis and infrared spectroscopy, respectively. The inclusion of glycerol exerted a plasticizing influence on the mechanical properties of the films, while keeping their transparency. Hydrodynamic and barrier properties were assessed through water uptake and water vapor/oxygen transmission rates, respectively, and obtained values were consistent with those of other cellulose-based materials. Furthermore, overall migration levels were below European regulation limits, as stated by using Tenax® as a dry food simulant. In addition, these bioplastics demonstrated good greaseproof performance, particularly at high glycerol content, and potential as packaging materials for bakery products. Biodegradability assessments were carried out by measuring the biological oxygen demand in seawater and high biodegradation rates induced by glycerol were observed.


Assuntos
Celulose , Embalagem de Alimentos , Glicerol , Embalagem de Alimentos/métodos , Glicerol/química , Celulose/química , Plásticos/química , Plastificantes/química , Vapor , Água/química , Biodegradação Ambiental , Plásticos Biodegradáveis/química
14.
Nano Lett ; 24(26): 7886-7894, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38842368

RESUMO

2D magnetic materials have attracted growing interest driven by their unique properties and potential applications. However, the scarcity of systems exhibiting magnetism at room temperature has limited their practical implementation into functional devices. Here we focus on the van der Waals ferromagnet Fe3GaTe2, which exhibits above-room-temperature magnetism (Tc = 350-380 K) and strong perpendicular anisotropy. Through first-principles calculations, we examine the magnetic properties of Fe3GaTe2 and compare them with those of Fe3GeTe2. Our calculations unveil the microscopic mechanisms governing their magnetic behavior, emphasizing the pivotal role of ferromagnetic in-plane couplings in the stabilization of the elevated Tc in Fe3GaTe2. Additionally, we predict the stability, substantial perpendicular anisotropy, and high Tc of the single-layer Fe3GaTe2. We also demonstrate the potential of strain engineering and electrostatic doping to modulate its magnetic properties. Our results incentivize the isolation of the monolayer and pave the way for the future optimization of Fe3GaTe2 in magnetic and spintronic nanodevices.

15.
J Med Virol ; 96(7): e29773, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38940448

RESUMO

The dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission are influenced by a variety of factors, including social restrictions and the emergence of distinct variants. In this study, we delve into the origins and dissemination of the Alpha, Delta, and Omicron-BA.1 variants of concern in Galicia, northwest Spain. For this, we leveraged genomic data collected by the EPICOVIGAL Consortium and from the GISAID database, along with mobility information from other Spanish regions and foreign countries. Our analysis indicates that initial introductions during the Alpha phase were predominantly from other Spanish regions and France. However, as the pandemic progressed, introductions from Portugal and the United States became increasingly significant. The number of detected introductions varied from 96 and 101 for Alpha and Delta to 39 for Omicron-BA.1. Most of these introductions left a low number of descendants (<10), suggesting a limited impact on the evolution of the pandemic in Galicia. Notably, Galicia's major coastal cities emerged as critical hubs for viral transmission, highlighting their role in sustaining and spreading the virus. This research emphasizes the critical role of regional connectivity in the spread of SARS-CoV-2 and offers essential insights for enhancing public health strategies and surveillance measures.


Assuntos
COVID-19 , SARS-CoV-2 , Espanha/epidemiologia , COVID-19/epidemiologia , COVID-19/transmissão , COVID-19/virologia , Humanos , SARS-CoV-2/genética , Genoma Viral , Filogenia , Pandemias
16.
bioRxiv ; 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38853899

RESUMO

The globus pallidus externus (GPe) is a central component of the basal ganglia circuit, receiving strong input from the indirect pathway and regulating a variety of functions, including locomotor output and habit formation. We recently showed that it also acts as a gatekeeper of cocaine-induced behavioral plasticity, as inhibition of parvalbumin-positive cells in the GPe (GPe PV ) prevents the development of cocaine-induced reward and sensitization. However, the molecular and circuit mechanisms underlying this function are unknown. Here we show that GPe PV cells control cocaine reward and sensitization by inhibiting GABAergic neurons in the substantia nigra pars reticulata (SNr GABA ), and ultimately, selectively modulating the activity of ventral tegmental area dopamine (VTA DA ) cells projecting to the lateral shell of the nucleus accumbens (NAcLat). A major input to GPe PV cells is the indirect pathway of the dorsomedial striatum (DMS D 2 ), which receives DAergic innervation from collaterals of VTA DA →NAcLat cells, making this a closed-loop circuit. Cocaine likely facilitates reward and sensitization not directly through actions in the GPe, but rather in the upstream DMS, where the cocaine-induced elevation of DA triggers a depression in DMS D 2 cell activity. This cocaine-induced elevation in DA levels can be blocked by inhibition of GPe PV cells, closing the loop. Interestingly, the level of GPe PV cell activity prior to cocaine administration is correlated with the extent of reward and sensitization that animals experience in response to future administration of cocaine, indicating that GPe PV cell activity is a key predictor of future behavioral responses to cocaine. Single nucleus RNA-sequencing of GPe cells indicated that genes encoding voltage-gated potassium channels KCNQ3 and KCNQ5 that control intrinsic cellular excitability are downregulated in GPe PV cells following a single cocaine exposure, contributing to the elevation in GPe PV cell excitability. Acutely activating channels containing KCNQ3 and/or KCNQ5 using the small molecule carnosic acid, a key psychoactive component of Salvia rosmarinus (rosemary) extract, reduced GPe PV cell excitability and also impaired cocaine reward, sensitization, and volitional cocaine intake, indicating its potential as a therapeutic to counteract psychostimulant use disorder. Our findings illuminate the molecular and circuit mechanisms by which the GPe orchestrates brain-wide changes in response to cocaine that are required for reward, sensitization, and self-administration behaviors.

17.
Chemistry ; : e202401092, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856100

RESUMO

Air pollution and greenhouse emissions are significant problems across various sectors, urging the need for advanced technologies to detect and capture harmful gases. In recent years, two-dimensional (2D) materials have attracted increasing attention due to their large surface-to-volume ratio and reactivity. Herein, we investigate the potential of single-layer CrSBr for gas sensing and capturing by means of first-principles calculations. We explore the adsorption behaviour of different pollutant gases (H2S, NH3, NO, NO2, CO and CO2) on this 2D ferromagnet and the impact of intrinsic defects on its magnetic properties. Interestingly, we find that Br vacancies enhance the adsorption of NH3, NO and NO2 and induce a selective frequency shift on the magnon dispersion. This work motivates the creation of novel magnonic gas sensing devices based on 2D van der Waals magnetic materials.

18.
ACS Appl Electron Mater ; 6(5): 2951-2959, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38828038

RESUMO

Ternary pnictide semiconductors with II-IV-V2 stoichiometry hold potential as cost-effective thermoelectric materials with suitable electronic transport properties, but their lattice thermal conductivities (κ) are typically too high. Insights into their vibrational properties are therefore crucial to finding strategies to reduce κ and achieve improved thermoelectric performance. We present a theoretical exploration of the lattice thermal conductivities for a set of pnictide semiconductors with ABX2 composition (A = Zn, Cd; B = Si, Ge, Sn; and X = P, As) using machine-learning-based regression algorithms to extract force constants from a reduced number of density functional theory simulations and then solving the Boltzmann transport equation for phonons. Our results align well with available experimental data, decreasing the mean absolute error by ∼3 W m-1 K-1 with respect to the best previous set of theoretical predictions. Zn-based ternary pnictides have, on average, more than double the thermal conductivity of the Cd-based compounds. Anisotropic behavior increases with the mass difference between A and B cations, but while the nature of the anion does not affect the structural anisotropy, the thermal conductivity anisotropy is typically higher for arsenides than for phosphides. We identify compounds such as CdGeAs2, for which nanostructuring to an affordable range of particle sizes could lead to κ values low enough for thermoelectric applications.

19.
Ann Biomed Eng ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842728

RESUMO

Physics-based modeling methods have the potential to investigate the mechanical factors associated with knee osteoarthritis (OA) and predict the future radiographic condition of the joint. However, it remains unclear what level of detail is optimal in these methods to achieve accurate prediction results in cohort studies. In this work, we extended a template-based finite element (FE) method to include the lateral and medial compartments of the tibiofemoral joint and simulated the mechanical responses of 97 knees under three conditions of gait loading. Furthermore, the effects of variations in cartilage thickness and failure equation on predicted cartilage degeneration were investigated. Our results showed that using neural network-based estimations of peak knee loading provided classification performances of 0.70 (AUC, p < 0.05) in distinguishing between knees that developed severe OA or mild OA and knees that did not develop OA eight years after a healthy radiographic baseline. However, FE models incorporating subject-specific femoral and tibial cartilage thickness did not improve this classification performance, suggesting there exists an optimal point between personalized loading and geometry for discrimination purposes. In summary, we proposed a modeling framework that streamlines the rapid generation of individualized knee models achieving promising classification performance while avoiding motion capture and cartilage image segmentation.

20.
Opt Express ; 32(10): 16790-16798, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858876

RESUMO

We present a method to determine the degree of temporal coherence of a quasimonochromatic vectorial light beam by polarimetric measurements. More specifically, we employ Michelson's interferometer in which the polarization Stokes parameters of the output (interference) beam are measured as a function of the time delay. Such a measurement enables us to deduce the magnitudes of the coherence (two-time) Stokes parameters, and hence the degree of coherence, of the input beam. Compared to existing methods the current technique has the benefits that neither optical elements in the arms of the interferometer nor visibility measurements are needed. The method is demonstrated with a laser diode and a filtered halogen source of various degrees of polarization.

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