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1.
J Res Adolesc ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961725

RESUMEN

Adolescents experience significant developmental changes during a time of heightened sensitivity to social cues, particularly rejection by peers, which can be especially overwhelming for those with elevated levels of social anxiety. Social evaluative decision-making tasks have been useful in uncovering the neural correlates of information processing biases; however, linking youths' task-based performance to individual differences in psychopathology (e.g., anxiety symptoms) has proven more elusive. Here, we address this weakness with drift diffusion modeling to decompose youths' performance on the social judgment paradigm (SJP) to determine if this approach is useful in discovering individual differences in anxiety symptoms, as well as puberty, age, and sex. A sample of 103 adolescents (55 males, Mage = 14.49, SD = 1.69) completed the SJP and self-report measures of anxiety, as well as self- and parent-reported measures of puberty. The decision threshold parameter, reflecting the amount of evidence needed to make a social evaluative decision, predicted youth self-reported anxiety, above and beyond typical metrics of SJP performance. Our results highlight the potential advantage of parsing task performance according to the underlying cognitive processes. Future research would likely benefit from applying computational modeling approaches to social judgment tasks when attempting to uncover performance-based individual differences in psychopathology.

2.
Sci Rep ; 14(1): 15135, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38956123

RESUMEN

The behavioral and neural responses to social exclusion were examined in women randomized to four conditions, varying in levels of attractiveness and friendliness. Informed by evolutionary theory, we predicted that being socially excluded by attractive unfriendly women would be more distressing than being excluded by unattractive women, irrespective of their friendliness level. Our results contradicted most of our predictions but provide important insights into women's responses to interpersonal conflict. Accounting for rejection sensitivity, P300 event-related potential amplitudes were largest when women were excluded by unattractive unfriendly women. This may be due to an expectancy violation or an annoyance with being excluded by women low on social desirability. An examination of anger rumination rates by condition suggests the latter. Only attractive women's attractiveness ratings were lowered in the unfriendly condition, indicating they were specifically punished for their exclusionary behavior. Women were more likely to select attractive women to compete against with one exception-they selected the Black attractive opponent less often than the White attractive opponent when presented as unfriendly. Finally, consistent with studies on retaliation in relation to social exclusion, women tended to rate competitors who rejected them as being more rude, more competitive, less attractive, less nice, and less happy than non-competitors. The ubiquity of social exclusion and its pointed emotional and physiological impact on women demands more research on this topic.


Asunto(s)
Belleza , Humanos , Femenino , Adulto Joven , Adulto , Distancia Psicológica , Deseabilidad Social , Amigos/psicología , Potenciales Relacionados con Evento P300/fisiología , Adolescente , Cara/fisiología
3.
Neurosurgery ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747605

RESUMEN

BACKGROUND AND OBJECTIVES: Vein of Galen malformation (VOGM), the result of arteriovenous shunting between choroidal and/or subependymal arteries and the embryologic prosencephalic vein, is among the most severe cerebrovascular disorders of childhood. We hypothesized that in situ analysis of the VOGM lesion using endoluminal tissue sampling (ETS) is feasible and may advance our understanding of VOGM genetics, pathogenesis, and maintenance. METHODS: We collected germline DNA (cheek swab) from patients and their families for genetic analysis. In situ VOGM "endothelial" cells (ECs), defined as CD31+ and CD45-, were obtained from coils through ETS during routine endovascular treatment. Autologous peripheral femoral ECs were also collected from the access sheath. Single-cell RNA sequencing of both VOGM and peripheral ECs was performed to demonstrate feasibility to define the transcriptional architecture. Comparison was also made with a published normative cerebrovascular transcriptome atlas. A subset of VOGM ECs was reserved for future DNA sequencing to assess for somatic and second-hit mutations. RESULTS: Our cohort contains 6 patients who underwent 10 ETS procedures from arterial and/or venous access during routine VOGM treatment (aged 12 days to ∼6 years). No periprocedural complications attributable to ETS occurred. Six unique coil types were used. ETS captured 98 ± 88 (mean ± SD; range 17-256) experimental ECs (CD31+ and CD45-). There was no discernible correlation between cell yield and coil type or route of access. Single-cell RNA sequencing demonstrated hierarchical clustering and unique cell populations within the VOGM EC compartment compared with peripheral EC controls when annotated using a publicly available cerebrovascular cell atlas. CONCLUSION: ETS may supplement investigations aimed at development of a molecular-genetic taxonomic classification scheme for VOGM. Moreover, results may eventually inform the selection of personalized pharmacologic or genetic therapies for VOGM and cerebrovascular disorders more broadly.

4.
PLoS One ; 19(5): e0303257, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38753830

RESUMEN

Patterns of single nucleotide polymorphisms (SNPs) in eukaryotic DNA are traditionally attributed to selective pressure, drift, identity descent, or related factors-without accounting for ways in which bias during de novo SNP formation, itself, might contribute. A functional and phenotypic analysis based on evolutionary resilience of DNA points to decreased numbers of non-synonymous SNPs in human and other genomes, with a predominant component of SNP depletion in the human gene pool caused by robust preferences during de novo SNP formation (rather than selective constraint). Ramifications of these findings are broad, belie a number of concepts regarding human evolution, and point to a novel interpretation of evolving DNA across diverse species.


Asunto(s)
Evolución Molecular , Polimorfismo de Nucleótido Simple , Humanos , Genoma Humano , Animales , Genoma/genética , Genómica/métodos
5.
J Psychiatr Res ; 173: 87-97, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38518572

RESUMEN

Post-event rumination, the extent to which one engages in persistent, detailed, and negative thinking following social situations, serves as a risk process in the pathophysiology of social anxiety. Although a substantial body of research has assessed post-event rumination and social anxiety, this literature has produced inconsistent results. We conducted a systematic review and meta-analysis to examine whether the magnitude of the association between post-event rumination and social anxiety varied as a function of questionnaire and/or task utilized. We included all studies reporting a correlation between post-event rumination and social anxiety symptomatology. Fisher's z correlation coefficients were calculated through random-effect meta-analyses. Results indicated a moderate association between post-event rumination and social anxiety symptomatology (r = 0.45, p < 0.001, 95%CI [0.40-0.50]). Subgroup meta-analyses indicated that the type of questionnaire used to assess post-event rumination (Q = 44.36, df = 3, p < 0.001) and social anxiety (Q = 26.44, df = 8, p < 0.001), as well as the task conducted prior to assessing post-event rumination (Q = 14.31, df = 2, p < 0.001), influenced the effect size. This study demonstrates a moderate relation between post-event rumination and social anxiety across the anxiety spectrum, illustrating the importance of treatments specifically targeting post-event rumination. Moreover, we highlight the importance of taking care when designing studies to explore relations between post-event rumination and social anxiety.

6.
Commun Chem ; 7(1): 65, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38538850

RESUMEN

Polyethylene terephthalate (PET), the most abundantly produced polyester plastic, can be depolymerized by the Ideonella sakaiensis PETase enzyme. Based on multiple PETase crystal structures, the reaction has been proposed to proceed via a two-step serine hydrolase mechanism mediated by a serine-histidine-aspartate catalytic triad. To elucidate the multi-step PETase catalytic mechanism, we use transition path sampling and likelihood maximization to identify optimal reaction coordinates for the PETase enzyme. We predict that deacylation is likely rate-limiting, and the reaction coordinates for both steps include elements describing nucleophilic attack, ester bond cleavage, and the "moving-histidine" mechanism. We find that the flexibility of Trp185 promotes the reaction, providing an explanation for decreased activity observed in mutations that restrict Trp185 motion. Overall, this study uses unbiased computational approaches to reveal the detailed reaction mechanism necessary for further engineering of an important class of enzymes for plastics bioconversion.

7.
Psychiatr Clin North Am ; 47(1): 65-86, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38302214

RESUMEN

Sleep disturbances and sleep disorders are prevalent in children/adolescents and have a bidirectional relationship with pediatric medical and mental health disorders. Screening tools and mechanisms for the evaluation and treatment of sleep disturbances and sleep disorders in the pediatric mental health clinic are less well-known; hence, sleep disturbances and disorders are under-recognized in the pediatric clinics. We present specific, validated screening and evaluation tools to identify sleep disturbances and sleep disorders in children/adolescents. We offer guidance related to the use of consumer wearables for sleep assessments and use of sleep telemedicine in pediatric mental health and primary care clinics.


Asunto(s)
Trastornos del Sueño-Vigilia , Humanos , Adolescente , Niño , Trastornos del Sueño-Vigilia/complicaciones , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/psicología , Sueño , Salud Mental
8.
Sci Adv ; 10(1): eadi7965, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38170770

RESUMEN

Plant secondary cell walls (SCWs) are composed of a heterogeneous interplay of three major biopolymers: cellulose, hemicelluloses, and lignin. Details regarding specific intermolecular interactions and higher-order architecture of the SCW superstructure remain ambiguous. Here, we use solid-state nuclear magnetic resonance (ssNMR) measurements to infer refined details about the structural configuration, intermolecular interactions, and relative proximity of all three major biopolymers within air-dried Populus wood. To enhance the utility of these findings and enable evaluation of hypotheses in a physics-based environment in silico, the NMR observables are articulated into an atomistic, macromolecular model for biopolymer assemblies within the plant SCW. Through molecular dynamics simulation, we quantitatively evaluate several variations of atomistic models to determine structural details that are corroborated by ssNMR measurements.


Asunto(s)
Populus , Celulosa , Espectroscopía de Resonancia Magnética , Biopolímeros , Plantas , Pared Celular
9.
Subst Use Misuse ; 59(3): 388-397, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37964628

RESUMEN

Background: Exposure to substances in utero may have significant early-life consequences. Less is known about the effects in emerging adulthood, particularly regarding patterns of substance use and related characteristics.Objectives: In this study, we recruited emerging adults, followed since birth, who had been prenatally exposed, or not, to cocaine. Individuals reported on their cannabis, alcohol, and tobacco use, and measures of impulsivity, anhedonia, emotional regulation, and mental health were obtained. Comparisons were made between emerging adults with prenatal cocaine exposure and those without. Correlations were performed between psychological measures and substance use, and regression analyses were conducted to determine potential pathways by which such measures may relate to prenatal exposure or substance use.Results: Individuals with prenatal cocaine exposure (vs. those without) used cannabis at younger ages, reported greater cannabis-use severity, and demonstrated higher impulsivity, state anxiety, and alexithymia. Earlier age of onset of cannabis use was associated with higher impulsivity, state anxiety, alexithymia, and social and physical anhedonia. Cannabis-use age-of-onset mediated the relationship between prenatal cocaine-exposure status and state anxiety and between prenatal cocaine-exposure status and cannabis-use severity in emerging adulthood but not relationships between prenatal cocaine-exposure status and impulsivity or alexithymia in emerging adulthood. Findings suggest that adults with prenatal cocaine exposure may use cannabis at younger ages, which may relate to increased anxiety and more severe use.Conclusions: These findings suggest both mechanisms and possible intervention targets to improve mental health in emerging adults with prenatal cocaine exposure.


Asunto(s)
Cannabis , Cocaína , Alucinógenos , Trastornos Relacionados con Sustancias , Embarazo , Adulto , Femenino , Humanos , Cannabis/efectos adversos , Trastornos Relacionados con Sustancias/psicología , Cocaína/efectos adversos , Uso de Tabaco , Etanol
10.
Macromolecules ; 56(21): 8547-8557, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-38024155

RESUMEN

A necessary transformation for a sustainable economy is the transition from fossil-derived plastics to polymers derived from biomass and waste resources. While renewable feedstocks can enhance material performance through unique chemical moieties, probing the vast material design space by experiment alone is not practically feasible. Here, we develop a machine-learning-based tool, PolyID, to reduce the design space of renewable feedstocks to enable efficient discovery of performance-advantaged, biobased polymers. PolyID is a multioutput, graph neural network specifically designed to increase accuracy and to enable quantitative structure-property relationship (QSPR) analysis for polymers. It includes a novel domain-of-validity method that was developed and applied to demonstrate how gaps in training data can be filled to improve accuracy. The model was benchmarked with both a 20% held-out subset of the original training data and 22 experimentally synthesized polymers. A mean absolute error for the glass transition temperatures of 19.8 and 26.4 °C was achieved for the test and experimental data sets, respectively. Predictions were made on polymers composed of monomers from four databases that contain biologically accessible small molecules: MetaCyc, MINEs, KEGG, and BiGG. From 1.4 × 106 accessible biobased polymers, we identified five poly(ethylene terephthalate) (PET) analogues with predicted improvements to thermal and transport performance. Experimental validation for one of the PET analogues demonstrated a glass transition temperature between 85 and 112 °C, which is higher than PET and within the predicted range of the PolyID tool. In addition to accurate predictions, we show how the model's predictions are explainable through analysis of individual bond importance for a biobased nylon. Overall, PolyID can aid the biobased polymer practitioner to navigate the vast number of renewable polymers to discover sustainable materials with enhanced performance.

11.
Res Sq ; 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37790365

RESUMEN

TCF1high progenitor CD8+ T cells mediate the efficacy of PD-1 blockade, however the mechanisms that govern their generation and maintenance are poorly understood. Here, we show that targeting glycolysis through deletion of pyruvate kinase muscle 2 (PKM2) results in elevated pentose phosphate pathway (PPP) activity, leading to enrichment of a TCF1high central memory-like phenotype and increased responsiveness to PD-1 blockade in vivo. PKM2KO CD8+ T cells showed reduced glycolytic flux, accumulation of glycolytic intermediates and PPP metabolites, and increased PPP cycling as determined by 1,2 13C glucose carbon tracing. Small molecule agonism of the PPP without acute glycolytic impairment skewed CD8+ T cells towards a TCF1high population, generated a unique transcriptional landscape, enhanced tumor control in mice in combination with PD-1 blockade, and promoted tumor killing in patient-derived tumor organoids. Our study demonstrates a new metabolic reprogramming that contributes to a progenitor-like T cell state amenable to checkpoint blockade.

12.
JCI Insight ; 8(19)2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-37643018

RESUMEN

The role of aberrant glycosylation in pancreatic ductal adenocarcinoma (PDAC) remains an under-investigated area of research. In this study, we determined that ST6 ß-galactoside α2,6 sialyltransferase 1 (ST6GAL1), which adds α2,6-linked sialic acids to N-glycosylated proteins, was upregulated in patients with early-stage PDAC and was further increased in advanced disease. A tumor-promoting function for ST6GAL1 was elucidated using tumor xenograft experiments with human PDAC cells. Additionally, we developed a genetically engineered mouse (GEM) model with transgenic expression of ST6GAL1 in the pancreas and found that mice with dual expression of ST6GAL1 and oncogenic KRASG12D had greatly accelerated PDAC progression compared with mice expressing KRASG12D alone. As ST6GAL1 imparts progenitor-like characteristics, we interrogated ST6GAL1's role in acinar to ductal metaplasia (ADM), a process that fosters neoplasia by reprogramming acinar cells into ductal, progenitor-like cells. We verified ST6GAL1 promotes ADM using multiple models including the 266-6 cell line, GEM-derived organoids and tissues, and an in vivo model of inflammation-induced ADM. EGFR is a key driver of ADM and is known to be activated by ST6GAL1-mediated sialylation. Importantly, EGFR activation was dramatically increased in acinar cells and organoids from mice with transgenic ST6GAL1 expression. These collective results highlight a glycosylation-dependent mechanism involved in early stages of pancreatic neoplasia.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Ratones , Animales , Neoplasias Pancreáticas/patología , Páncreas/patología , Carcinoma Ductal Pancreático/patología , Receptores ErbB/genética , Metaplasia/patología , Sialiltransferasas/genética , beta-D-Galactósido alfa 2-6-Sialiltransferasa , Antígenos CD
13.
J Affect Disord Rep ; 132023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37396954

RESUMEN

Background: Adolescence is a time of heightened risk for developing depression and also a critical period for the development and integration of self-identity. Despite this, the relation between the neurophysiological correlates of self-referential processing and major depressive symptoms in youth is not well understood. Here, we leverage computational modeling of the self-referential encoding task (SRET) to identify behavioral moderators of the association between the posterior late positive potential (LPP), an event-related potential associated with emotion regulation, and youth self-reported symptoms of depression. Specifically, within a drift-diffusion framework, we evaluated whether the association between the posterior LPP and youth symptoms of major depression was moderated by drift rate, a parameter reflecting processing efficiency during self-evaluative decisions. Methods: A sample of 106 adolescents, aged 12 to 17 (53% male; Mage = 14.49, SD = 1.70), completed the SRET with concurrent high-density electroencephalography and self-report measures of depression and anxiety. Results: Findings indicated a significant moderation: for youth showing greater processing efficiency (drift rate) when responding to negative compared to positive words, larger posterior LPPs predicted greater depressive symptom severity. Limitations: We relied on a community sample and our study was cross-sectional in nature. Future longitudinal work with clinically depressed youth would be beneficial. Conclusions: Our results suggest a neurobehavioral model of adolescent depression wherein efficient processing of negative information co-occurs with increased demands on affective self-regulation. Our findings also have clinical relevance; youth's neurophysiological response (posterior LPP) and performance during the SRET may serve as a novel target for tracking treatment-related changes in one's self-identity.

14.
Nat Biomed Eng ; 7(8): 1028-1039, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37400715

RESUMEN

In conventional positron emission tomography (PET), only one radiotracer can be imaged at a time, because all PET isotopes produce the same two 511 keV annihilation photons. Here we describe an image reconstruction method for the simultaneous in vivo imaging of two PET tracers and thereby the independent quantification of two molecular signals. This method of multiplexed PET imaging leverages the 350-700 keV range to maximize the capture of 511 keV annihilation photons and prompt γ-ray emission in the same energy window, hence eliminating the need for energy discrimination during reconstruction or for signal separation beforehand. We used multiplexed PET to track, in mice with subcutaneous tumours, the biodistributions of intravenously injected [124I]I-trametinib and 2-deoxy-2-[18F]fluoro-D-glucose, [124I]I-trametinib and its nanoparticle carrier [89Zr]Zr-ferumoxytol, and the prostate-specific membrane antigen (PSMA) and infused PSMA-targeted chimaeric antigen receptor T cells after the systemic administration of [68Ga]Ga-PSMA-11 and [124I]I. Multiplexed PET provides more information depth, gives new uses to prompt γ-ray-emitting isotopes, reduces radiation burden by omitting the need for an additional computed-tomography scan and can be implemented on preclinical and clinical systems without any modifications in hardware or image acquisition software.


Asunto(s)
Electrones , Tomografía de Emisión de Positrones , Masculino , Animales , Ratones , Tomografía de Emisión de Positrones/métodos , Radioisótopos de Yodo , Tomografía Computarizada por Rayos X
15.
Psychol Med ; 53(16): 7857-7864, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37485677

RESUMEN

BACKGROUND: Comprehensive Behavioral Intervention for Tics (CBIT) is recommended as a first-line treatment for Tourette syndrome in children and adults. While there is strong evidence proving its efficacy, the mechanisms of reduction in tic severity during CBIT are still poorly understood. In a recent study, our group identified a functional brain network involved in tic suppression in children with TS. We reasoned that voluntary tic suppression and CBIT may share some mechanisms and thus we wanted to assess whether functional connectivity during tic suppression was associated with CBIT outcome. METHODS: Thirty-two children with TS, aged 8 to 13 years old, participated in a randomized controlled trial of CBIT v. a treatment-as-usual control condition. EEG was recorded during tic suppression in all participants at baseline and endpoint. We used a source-reconstructed EEG connectivity pipeline to assess functional connectivity during tic suppression. RESULTS: Functional connectivity during tic suppression did not change from baseline to endpoint. However, baseline tic suppression-related functional connectivity specifically predicted the decrease in vocal tic severity from baseline to endpoint in the CBIT group. Supplementary analyses revealed that the functional connectivity between the right superior frontal gyrus and the right angular gyrus was mainly driving this effect. CONCLUSIONS: This study revealed that functional connectivity during tic suppression at baseline predicted reduction in vocal tic severity. These results suggest probable overlap between the mechanisms of voluntary tic suppression and those of behavior therapy for tics.


Asunto(s)
Trastornos de Tic , Tics , Síndrome de Tourette , Adulto , Niño , Humanos , Adolescente , Tics/terapia , Tics/complicaciones , Síndrome de Tourette/terapia , Índice de Severidad de la Enfermedad , Trastornos de Tic/terapia , Terapia Conductista/métodos
16.
Brain Res ; 1816: 148468, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37336317

RESUMEN

During pregnancy and the postpartum period, changes in brain volume and in motivational, sensory, cognitive, and emotional processes have been described. However, to date, longitudinal modifications of brain function have been understudied. To explore regional cortical coupling, in pregnancy and at 3 months postpartum, we analyzed resting-state electroencephalographic (EEG) coherence in the delta, theta, alpha1, alpha2, beta1, and beta2 frequency bands across frontal and parietal regions of the maternal brain (Fp1, Fp2, F3, F4, P3, and P4). We found that from pregnancy to the postpartum period, mothers showed less intrahemispheric EEG coherence between the frontal and parietal regions in the alpha1 and alpha2 bands, as well as greater interhemispheric EEG coherence between frontopolar regions in the beta2 band. These changes suggest decreased inhibition of neural circuits. These neurophysiological changes may represent an adaptive process characteristic of motherhood.


Asunto(s)
Encéfalo , Electroencefalografía , Embarazo , Femenino , Humanos , Encéfalo/fisiología , Lóbulo Parietal , Periodo Posparto , Emociones
17.
Front Immunol ; 14: 1082078, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37256130

RESUMEN

Kidney macrophages are comprised of both monocyte-derived and tissue resident populations; however, the heterogeneity of kidney macrophages and factors that regulate their heterogeneity are poorly understood. Herein, we performed single cell RNA sequencing (scRNAseq), fate mapping, and parabiosis to define the cellular heterogeneity of kidney macrophages in healthy mice. Our data indicate that healthy mouse kidneys contain four major subsets of monocytes and two major subsets of kidney resident macrophages (KRM) including a population with enriched Ccr2 expression, suggesting monocyte origin. Surprisingly, fate mapping data using the newly developed Ms4a3Cre Rosa Stopf/f TdT model indicate that less than 50% of Ccr2+ KRM are derived from Ly6chi monocytes. Instead, we find that Ccr2 expression in KRM reflects their spatial distribution as this cell population is almost exclusively found in the kidney cortex. We also identified Cx3cr1 as a gene that governs cortex specific accumulation of Ccr2+ KRM and show that loss of Ccr2+ KRM reduces the severity of cystic kidney disease in a mouse model where cysts are mainly localized to the kidney cortex. Collectively, our data indicate that Cx3cr1 regulates KRM heterogeneity and niche-specific disease progression.


Asunto(s)
Macrófagos , Monocitos , Ratones , Animales , Macrófagos/metabolismo , Monocitos/metabolismo , Riñón/metabolismo , Receptores de Quimiocina/metabolismo , Modelos Animales de Enfermedad , Receptor 1 de Quimiocinas CX3C/genética , Receptor 1 de Quimiocinas CX3C/metabolismo
18.
Cell Surf ; 9: 100105, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37063382

RESUMEN

Secondary plant cell walls are composed of carbohydrate and lignin polymers, and collectively represent a significant renewable resource. Leveraging these resources depends in part on a mechanistic understanding for diffusive processes within plant cell walls. Common wood protection treatments and biomass conversion processes to create biorefinery feedstocks feature ion or solvent diffusion within the cell wall. X-ray fluorescence microscopy experiments have determined that ionic diffusion rates are dependent on cell wall hydration as well as the ionic species through non-linear relationships. In this work, we use classical molecular dynamics simulations to map the diffusion behavior of different plant cell wall components (cellulose, hemicellulose, lignin), ions (Na+, K+, Cu2+, Cl-) and water within a model for an intact plant cell wall at various hydration states (3-30 wt% water). From these simulations, we analyze the contacts between different plant cell wall components with each other and their interaction with the ions. Generally, diffusion increases with increasing hydration, with lignin and hemicellulose components increasing diffusion by an order of magnitude over the tested hydration range. Ion diffusion depends on charge. Positively charged cations preferentially interact with hemicellulose components, which include negatively charged carboxylates. As a result, positive ions diffuse more slowly than negatively charged ions. Measured diffusion coefficients are largely observed to best fit piecewise linear trends, with an inflection point between 10 and 15% hydration. These observations shed light onto the molecular mechanisms for diffusive processes within secondary plant cell walls at atomic resolution.

19.
JCI Insight ; 8(10)2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37040185

RESUMEN

Viral illnesses like SARS-CoV-2 have pathologic effects on nonrespiratory organs in the absence of direct viral infection. We injected mice with cocktails of rodent equivalents of human cytokine storms resulting from SARS-CoV-2/COVID-19 or rhinovirus common cold infection. At low doses, COVID-19 cocktails induced glomerular injury and albuminuria in zinc fingers and homeoboxes 2 (Zhx2) hypomorph and Zhx2+/+ mice to mimic COVID-19-related proteinuria. Common Cold cocktail induced albuminuria selectively in Zhx2 hypomorph mice to model relapse of minimal change disease, which improved after depletion of TNF-α, soluble IL-4Rα, or IL-6. The Zhx2 hypomorph state increased cell membrane to nuclear migration of podocyte ZHX proteins in vivo (both cocktails) and lowered phosphorylated STAT6 activation (COVID-19 cocktail) in vitro. At higher doses, COVID-19 cocktails induced acute heart injury, myocarditis, pericarditis, acute liver injury, acute kidney injury, and high mortality in Zhx2+/+ mice, whereas Zhx2 hypomorph mice were relatively protected, due in part to early, asynchronous activation of STAT5 and STAT6 pathways in these organs. Dual depletion of cytokine combinations of TNF-α with IL-2, IL-13, or IL-4 in Zhx2+/+ mice reduced multiorgan injury and eliminated mortality. Using genome sequencing and CRISPR/Cas9, an insertion upstream of ZHX2 was identified as a cause of the human ZHX2 hypomorph state.


Asunto(s)
COVID-19 , Resfriado Común , Humanos , Ratones , Animales , Proteínas de Homeodominio/genética , Albuminuria , Factor de Necrosis Tumoral alfa , Síndrome de Liberación de Citoquinas , SARS-CoV-2/metabolismo , Factores de Transcripción/genética
20.
Expert Opin Pharmacother ; 24(7): 835-847, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37074259

RESUMEN

INTRODUCTION: Anxiety disorders are the most prevalent psychiatric disorders among youth. Among the various anxiety disorders, generalized anxiety disorder is particularly prevalent. Youth with GAD appear at elevated risk of developing other anxiety disorders, mood disorder, and substance use disorders. Functional outcomes of youth with GAD can be improved through early recognition and treatment, thus promoting better longer-term outcomes. AREAS COVERED: The current article summarizes evidence-based state-of-the-art pharmacotherapy for pediatric GAD based on open-label, randomized, and controlled trials. Two electronic databases (PubMed and Scopus) were systematically searched in April 2022 for relevant publications. EXPERT OPINION: The literature supports a combination of psychotherapy and pharmacotherapy as being associated with better outcomes when compared to mono-therapies. While longer-term follow-ups are limited, one such study does challenge this notion. Both selective serotonin reuptake inhibitors (SSRIs) and selective norepinephrine reuptake inhibitors (SNRIs) have been found across studies to have moderate effect sizes in the treatment of pediatric anxiety disorders. SSRIs continue to be a first-line intervention, whereas SNRIs may be considered a second-line treatment. While more evidence is needed, there are emerging data indicating that SSRIs are associated with a more rapid and greater reduction in anxiety symptoms when compared to SNRIs.


Asunto(s)
Inhibidores Selectivos de la Recaptación de Serotonina , Inhibidores de Captación de Serotonina y Norepinefrina , Adolescente , Humanos , Niño , Inhibidores de Captación de Serotonina y Norepinefrina/uso terapéutico , Trastornos de Ansiedad/tratamiento farmacológico
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