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1.
Philos Trans A Math Phys Eng Sci ; 382(2278): 20240020, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39069764

RESUMEN

Periodic wave barriers (PWB) open a new window for vibration mitigation. However, the Doppler effect is rarely considered in most of the previous investigations on the control of ambient vibration induced by moving loads. This article reveals the significance of the speed and frequency of moving loads on surface waves, and improves the design method of PWB for ambient vibration reduction and isolation. First, the theoretical expression of the main frequency band of surface waves propagating in an elastic half-space caused by a moving load was obtained. Comparisons with the numerical results under three different types of traffic loads were also conducted and good agreement was found. Second, the theoretical expression and numerical results were verified by experimental studies. Some inherent properties of wave propagation caused by a moving load in an elastic half-space were also revealed. Third, two kinds of PWBs, i.e. periodic empty trench barrier and periodic pile barrier, were introduced to mitigate wave propagation. It has been confirmed that if the attenuation zones of PWB match the target frequency bands given by the theoretical expression, good vibration mitigation can be achieved. This article is part of the theme issue 'Current developments in elastic and acoustic metamaterials science (Part 1)'.

2.
Antioxidants (Basel) ; 13(7)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39061886

RESUMEN

Periodontitis, characterized by inflammation and loss of periodontal tissue, is a significant health complication for individuals with diabetes mellitus (DM). Buildup of advanced glycation end-products (AGEs) in DM poses an increased risk of periodontitis via inflammaging. Ganoderma immunomodulatory protein (GMI) shows promise in suppressing inflammaging by mitigating oxidative stress and inflammation via Nrf2 modulation. However, its specific protective effects are not fully understood. Thus, this study aimed to investigate GMI's anti-inflammaging properties and its underlying mechanism in diabetic-associated periodontitis (DP). We first simulated DP by culturing human gingival fibroblasts (HGFs) with AGEs and lipopolysaccharides from P. gingivalis (LPS). We then evaluated the impact of GMI on cell proliferation, migration and wound healing. Additionally, we assessed GMI's effects on the components of inflammaging such as reactive oxygen species (ROS) formation, cellular senescence expression, IL-6 and IL-8 secretions, and NF-κB phosphorylation. Next, we explored whether GMI's anti-inflammaging effects are mediated through the Nrf2 pathway by evaluating Nrf2 and HO-1, followed by the assessment of IL-6 and IL-8 post-Nrf2 knockdown. Our findings revealed that GMI treatment suppressed ROS production, cell senescence, IL-6 and IL-8 and NF-κB phosphorylation. Furthermore, GMI upregulated Nrf2/HO-1 expression and its protective effects were reversed when Nrf2 was knocked down. In conclusion, GMI exerts its anti-inflammaging effect via the modulation of the Nrf2/NF-κB signaling axis in DP in vitro, highlighting its potential as an effective adjunct treatment for diabetes-related periodontitis.

3.
J Dent Sci ; 19(3): 1389-1395, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39035323

RESUMEN

Background/purpose: Accumulating evidence has suggested that treatment failure of cancer therapy can be attributed to cancer stem cells (CSCs). Among numerous regulators of cancer stemness, non-coding RNAs (ncRNAs) have gained significant attention recently. In this study, we examined the role of gastric adenocarcinoma predictive long intergenic noncoding RNA (GAPLINC) in oral CSCs (OCSCs). Materials and methods: RNA Sequencing and quantitative real-time polymerase chain reaction (qRT-PCR) were used to determine the expression of GAPLINC. Flow cytometry and sphere-forming assay were exploited to isolate OCSCs. Measurement of aldehyde dehydrogenase 1 (ALDH1) activity, CD44 expressing cells, and various phenotypic assays, such as self-renewal, migration, invasion, and colony-forming abilities, were conducted in CSCs of two types of oral cancer cells (SAS and GNM) following the knockdown of GAPLINC. A luciferase reporter was also carried out to validate the direct interaction between GAPLINC and microRNA (miR)-331-3p. Results: Our results showed that GAPLINC was overexpressed in OCSCs from patient-derived and oral cancer cell lines. We demonstrated that silencing of GAPLINC in OCSCs downregulated various CSC hallmarks, such as ALDH1 activity, percentage of CD44-expressing cells, self-renewal capacity, and colony-forming ability. Moreover, our results revealed that the effect of GAPLINC on cancer stemness was mediated by direct repression of miR-331-3p. Conclusion: These data have potential clinical implications in that we unraveled the aberrant upregulation of GAPLINC and demonstrated that suppression of GAPLINC may reduce cancer stemness via sequestering miR-331-3p.

4.
Plant Cell Environ ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39041727

RESUMEN

Very-long-chain fatty acids (VLCFAs) are essential precursors for plant membrane lipids, cuticular waxes, suberin, and storage oils. Integral to the fatty acid elongase (FAE) complex, 3-ketoacyl-CoA synthases (KCSs) function as crucial enzymes in the VLCFA pathway, determining the chain length of VLCFA. This study explores the in-planta role of the KCS19 gene. KCS19 is predominantly expressed in leaves and stem epidermis, sepals, styles, early silique walls, beaks, pedicels, and mature embryos. Localized in the endoplasmic reticulum, KCS19 interacts with other FAE proteins. kcs19 knockout mutants displayed reduced total wax and wax crystals, particularly alkanes, while KCS19 overexpression increased these components and wax crystals. Moreover, the cuticle permeability was higher for the kcs19 mutants compared to the wild type, rendering them more susceptible to drought and salt stress, whereas KCS19 overexpression enhanced drought and salt tolerance. Disrupting KCS19 increased C18 species and decreased C20 and longer species in seed fatty acids, indicating its role in elongating C18 to C20 VLCFAs, potentially up to C24 for seed storage lipids. Collectively, KCS19-mediated VLCFA synthesis is required for cuticular wax biosynthesis and seed storage lipids, impacting plant responses to abiotic stress.

5.
Child Dev ; 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080971

RESUMEN

Data from three NIH Environmental influences on Child Health Outcomes (ECHO) Program cohorts that collected the HOME-Infant-Toddler (HOME-IT age 0-3 years) version were used to examine the reliability of a brief scale of caregiver support and cognitive stimulation. Participants with HOME-IT data (N = 2518) were included in this analysis. Mean child age at HOME-IT assessment was 1.51 years, 48% of children were female, and 43% of children identified as Black. A four-stage analysis plan was used to evaluate item response theory assumptions, item response theory model fit, monotonicity, scalability, item fit, and differential item functioning. Results indicate the feasibility of developing a reliable 10-item scale (reliability >0.7) with particularly high precision for children with lower levels of cognitive stimulation.

6.
Pediatr Blood Cancer ; 71(9): e31176, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38967585

RESUMEN

INTRODUCTION: Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. Our aim was to identify prognostic genetic markers for patients with neuroblastoma, who were treated with the Taiwan Pediatric Oncology Group (TPOG) neuroblastoma N2002 protocol, to improve risk stratification and inform treatment. METHODS: Our analysis was based on 53 primary neuroblastoma specimens, diagnosed pre-chemotherapy, and 11 paired tumor relapse specimens. Deep sequencing of 113 target genes was performed using a custom panel. Multiplex ligation-dependent probe amplification was performed to identify clinical outcomes related to copy-number variations. RESULTS: We identified 128 variations associated with survival, with the number of variations being higher in the relapse than that in the diagnostic specimen (p = .03). The risk of event and mortality was higher among patients with a tumor mutational burden ≥10 than that in patients with a lower burden (p < .0001). Multivariate analysis identified tumor mutational burden, MYCN amplification, and chromosome 3p deletion as significant prognostic factors, independent of age at diagnosis, sex, and tumor stage. The 5-year event-free survival and overall survival rate was lower among patients with high tumor burden than in patients with low tumor burden. Furthermore, there was no survival of patients with an ALK F1147L variation at 5 years after diagnosis. CONCLUSIONS: Genome sequencing to determine the tumor mutational burden and ALK variations can improve the risk classification of neuroblastoma and inform treatment.


Asunto(s)
Mutación , Neuroblastoma , Humanos , Neuroblastoma/genética , Neuroblastoma/mortalidad , Neuroblastoma/patología , Masculino , Femenino , Preescolar , Lactante , Niño , Pronóstico , Biomarcadores de Tumor/genética , Tasa de Supervivencia , Estudios de Seguimiento , Variaciones en el Número de Copia de ADN , Carga Tumoral , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Adolescente
7.
Int J Hyg Environ Health ; 260: 114407, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38879913

RESUMEN

BACKGROUND: Executive functions develop rapidly in childhood, enabling problem-solving, focused attention, and planning. Exposures to environmental toxicants in pregnancy may impair healthy executive function development in children. There is increasing concern regarding polycyclic aromatic hydrocarbons (PAHs) given their ability to transfer across the placenta and the fetal blood-brain barrier, yet evidence from epidemiological studies is limited. METHODS: We examined associations between prenatal PAH exposure and executive functions in 814 children of non-smoking mothers from two U.S. cohorts in the ECHO-PATHWAYS Consortium. Seven mono-hydroxylated PAH metabolites were measured in mid-pregnancy urine and analyzed individually and as mixtures. Three executive function domains were measured at age 8-9: cognitive flexibility, working memory, and inhibitory control. A composite score quantifying overall performance was further calculated. We fitted linear regressions adjusted for socio-demographics, maternal health behaviors, and psychological measures, and examined modification by child sex and stressful life events in pregnancy. Bayesian kernel machine regression was performed to estimate the interactive and overall effects of the PAH mixture. RESULTS: The results from primary analysis of linear regressions were generally null, and no modification by child sex or maternal stress was indicated. Mixture analyses suggested several pairwise interactions between individual PAH metabolites in varied directions on working memory, particularly interactions between 2/3/9-FLUO and other PAH metabolites, but no overall or individual effects were evident. CONCLUSION: We conducted a novel exploration of PAH-executive functions association in a large, combined sample from two cohorts. Although findings were predominantly null, the study carries important implications for future research and contributes to evolving science regarding developmental origins of diseases.


Asunto(s)
Función Ejecutiva , Hidrocarburos Policíclicos Aromáticos , Efectos Tardíos de la Exposición Prenatal , Humanos , Femenino , Hidrocarburos Policíclicos Aromáticos/orina , Embarazo , Función Ejecutiva/efectos de los fármacos , Niño , Masculino , Estudios de Cohortes , Contaminantes Ambientales/orina , Adulto , Memoria a Corto Plazo/efectos de los fármacos , Exposición Materna
8.
Epidemiology ; 35(5): 676-688, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38871635

RESUMEN

BACKGROUND: Executive function, which develops rapidly in childhood, enables problem-solving, focused attention, and planning. Animal models describe executive function decrements associated with ambient air pollution exposure, but epidemiologic studies are limited. METHODS: We examined associations between early childhood air pollution exposure and school-aged executive function in 1235 children from three US pregnancy cohorts in the ECHO-PATHWAYS Consortium. We derived point-based residential exposures to ambient particulate matter ≤2.5 µm in aerodynamic diameter (PM 2.5 ), nitrogen dioxide (NO 2 ), and ozone (O 3 ) at ages 0-4 years from spatiotemporal models with a 2-week resolution. We assessed executive function across three domains, cognitive flexibility, working memory, and inhibitory control, using performance-based measures and calculated a composite score quantifying overall performance. We fitted linear regressions to assess air pollution and child executive function associations, adjusting for sociodemographic characteristics, maternal mental health, and health behaviors, and examined modification by child sex, maternal education, and neighborhood educational opportunity. RESULTS: In the overall sample, we found hypothesized inverse associations in crude but not adjusted models. Modified associations between NO 2 exposure and working memory by neighborhood education opportunity were present ( Pinteraction = 0.05), with inverse associations more pronounced in the "high" and "very high" categories. Associations of interest did not differ by child sex or maternal education. CONCLUSION: This work contributes to the evolving science regarding early-life environmental exposures and child development. There remains a need for continued exploration in future research endeavors, to elucidate the complex interplay between natural environment and social determinants influencing child neurodevelopment.


Asunto(s)
Contaminación del Aire , Exposición a Riesgos Ambientales , Función Ejecutiva , Dióxido de Nitrógeno , Material Particulado , Humanos , Femenino , Masculino , Preescolar , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Material Particulado/análisis , Dióxido de Nitrógeno/análisis , Lactante , Estados Unidos , Exposición a Riesgos Ambientales/efectos adversos , Niño , Estudios de Cohortes , Memoria a Corto Plazo/efectos de los fármacos , Ozono/análisis , Ozono/efectos adversos , Recién Nacido , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/efectos adversos , Embarazo , Modelos Lineales
9.
J Dent Sci ; 19(2): 1083-1086, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38618124

RESUMEN

Background/purpose: The teaching practice research program was initiated by Taiwan's Ministry of Education in 2018 to improve medical teaching quality. This study analyzed dental teaching projects conducted under this program from 2018 to 2023. Materials and methods: Data of submitted and approved medical (including dental) teaching projects from 2018 to 2023 were obtained from the annual reports released by the program committee. The annual passing rates were calculated by dividing the number of approved dental teaching projects by the total number of approved medical teaching projects in the category of medical and healthcare sciences in a particular year. The 24 approved dental teaching projects were reviewed, classified into different topics in the dental field, and then reported. Results: There were 24 approved dental teaching projects out of a total of 822 approved medical teaching projects from 2018 to 2023. The annual passing rates increased gradually from 2018 (1.4 %) to 2022 (3.9 %) and 2023 (3.8 %) with an overall mean passing rate of 2.9 % over a period of 6 years. Of the 24 approved dental teaching projects, digital dentistry was the most common teaching research topic (9 projects), followed by new teaching models (7 projects), 3D technology (3 projects), endodontics (3 projects), dental histology (one project), and evidence-based method (one project). Conclusion: Digital dentistry and new teaching models were the two predominant dental teaching research topics, suggesting that both are the modern trends in the dental education. However, the dental teaching research projects are still very limited in 8 Taiwanese dental schools.

10.
Phys Rev Lett ; 132(12): 126201, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38579216

RESUMEN

The competition between on-site electronic correlation and local crystal field stands out as a captivating topic in research. However, its physical ramifications often get overshadowed by influences of strong periodic potential and orbital hybridization. The present study reveals this competition may become more pronounced or even dominant in two-dimensional systems, driven by the combined effects of dimensional confinement and orbital anisotropy. This leads to electronic orbital reconstruction in certain perovskite superlattices or thin films. To explore the emerging physics, we investigate the interfacial orbital disorder-order transition with an effective Hamiltonian and how to modulate this transition through strains.

11.
J Dent Sci ; 19(2): 1222-1223, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38618080
12.
Int J Hyg Environ Health ; 258: 114333, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460460

RESUMEN

We examined associations between prenatal fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) exposures and child respiratory outcomes through age 8-9 years in 1279 ECHO-PATHWAYS Consortium mother-child dyads. We averaged spatiotemporally modeled air pollutant exposures during four fetal lung development phases: pseudoglandular (5-16 weeks), canalicular (16-24 weeks), saccular (24-36 weeks), and alveolar (36+ weeks). We estimated adjusted relative risks (RR) for current asthma at age 8-9 and asthma with recent exacerbation or atopic disease, and odds ratios (OR) for wheezing trajectories using modified Poisson and multinomial logistic regression, respectively. Effect modification by child sex, maternal asthma, and prenatal environmental tobacco smoke was explored. Across all outcomes, 95% confidence intervals (CI) included the null for all estimates of associations between prenatal air pollution exposures and respiratory outcomes. Pseudoglandular PM2.5 exposure modestly increased risk of current asthma (RRadj = 1.15, 95% CI: 0.88-1.51); canalicular PM2.5 exposure modestly increased risk of asthma with recent exacerbation (RRadj = 1.26, 95% CI: 0.86-1.86) and persistent wheezing (ORadj = 1.28, 95% CI: 0.86-1.89). Similar findings were observed for O3, but not NO2, and associations were strengthened among mothers without asthma. While not statistically distinguishable from the null, trends in effect estimates suggest some adverse associations of early pregnancy air pollution exposures with child respiratory conditions, warranting confirmation in larger samples.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Asma , Niño , Embarazo , Femenino , Humanos , Ruidos Respiratorios , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , Asma/epidemiología , Asma/inducido químicamente , Material Particulado/análisis , Dióxido de Nitrógeno , Exposición a Riesgos Ambientales/efectos adversos
13.
JAMA Neurol ; 81(5): 549-550, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38436991

RESUMEN

This case report studies a 12-year-old boy with a family history of X-linked adrenal leukodystrophy and his 8-year-old younger brother.


Asunto(s)
Adrenoleucodistrofia , Humanos , Masculino , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/diagnóstico , Heterocigoto , Cariotipo , Miembro 1 de la Subfamilia D de Transportador de Casetes de Unión al ATP
14.
Environ Health ; 23(1): 26, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38454435

RESUMEN

BACKGROUND AND AIM: Studies suggest prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) may influence wheezing or asthma in preschool-aged children. However, the impact of prenatal PAH exposure on asthma and wheeze in middle childhood remain unclear. We investigated these associations in socio-demographically diverse participants from the ECHO PATHWAYS multi-cohort consortium. METHODS: We included 1,081 birth parent-child dyads across five U.S. cities. Maternal urinary mono-hydroxylated PAH metabolite concentrations (OH-PAH) were measured during mid-pregnancy. Asthma at age 8-9 years and wheezing trajectory across childhood were characterized by caregiver reported asthma diagnosis and asthma/wheeze symptoms. We used logistic and multinomial regression to estimate odds ratios of asthma and childhood wheezing trajectories associated with five individual OH-PAHs, adjusting for urine specific gravity, various maternal and child characteristics, study site, prenatal and postnatal smoke exposure, and birth year and season in single metabolite and mutually adjusted models. We used multiplicative interaction terms to evaluate effect modification by child sex and explored OH-PAH mixture effects through Weighted Quantile Sum regression. RESULTS: The prevalence of asthma in the study population was 10%. We found limited evidence of adverse associations between pregnancy OH-PAH concentrations and asthma or wheezing trajectories. We observed adverse associations between 1/9-hydroxyphenanthrene and asthma and persistent wheeze among girls, and evidence of inverse associations with asthma for 1-hydroxynathpthalene, which was stronger among boys, though tests for effect modification by child sex were not statistically significant. CONCLUSIONS: In a large, multi-site cohort, we did not find strong evidence of an association between prenatal exposure to PAHs and child asthma at age 8-9 years, though some adverse associations were observed among girls.


Asunto(s)
Asma , Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Efectos Tardíos de la Exposición Prenatal , Niño , Embarazo , Masculino , Femenino , Preescolar , Humanos , Estudios Longitudinales , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Ruidos Respiratorios , Asma/inducido químicamente , Asma/epidemiología
15.
Diagnostics (Basel) ; 14(4)2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38396404

RESUMEN

Alzheimer's disease (AD) and vascular dementia (VaD) are the two most common forms of dementia. However, their neuropsychological and pathological features often overlap, making it difficult to distinguish between AD and VaD. In addition to clinical consultation and laboratory examinations, clinical dementia diagnosis in Taiwan will also include Tc-99m-ECD SPECT imaging examination. Through machine learning and deep learning technology, we explored the feasibility of using the above clinical practice data to distinguish AD and VaD. We used the physiological data (33 features) and Tc-99m-ECD SPECT images of 112 AD patients and 85 VaD patients in the Taiwanese Nuclear Medicine Brain Image Database to train the classification model. The results, after filtering by the number of SVM RFE 5-fold features, show that the average accuracy of physiological data in distinguishing AD/VaD is 81.22% and the AUC is 0.836; the average accuracy of training images using the Inception V3 model is 85% and the AUC is 0.95. Finally, Grad-CAM heatmap was used to visualize the areas of concern of the model and compared with the SPM analysis method to further understand the differences. This research method can quickly use machine learning and deep learning models to automatically extract image features based on a small amount of general clinical data to objectively distinguish AD and VaD.

16.
Environ Sci Pollut Res Int ; 31(10): 16011-16027, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38308784

RESUMEN

Lithium is an indispensable resource for the next generation of clean technology. Promoting the development of lithium industry has become a global consensus, with China being no exception. The development process involves not only the growth and degeneration of lithium products but also the path-dependency issues arising from resources and technology. This study, based on the perspective of product space structure, constructs China's lithium product network to study its pattern evolution and predict the development direction. Then, according to the current situation and pattern evolution trends, potential advantageous lithium products and advantage-degraded lithium products are identified, and tactics for expanding chains and breaking chains are formulated for them, presenting strategies for the integrated and fragmentated development of China's lithium products. This aims to steer China's lithium products towards a more orderly and closely interconnected direction, representing the arrow of development for China's lithium products.


Asunto(s)
Industrias , Litio , China , Tecnología
17.
Microorganisms ; 12(1)2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38276196

RESUMEN

Subterranean karst caves are windows into the terrestrial subsurface to deconstruct the dimensions of mycobiome fingerprints. However, impeded by the constraints of remote locations, the inaccessibility of specimens and technical limitations, the mycobiome of subterranean karst caves has remained largely unknown. Weathered rock and sediment samples were collected from Luohandu cave (Guilin, Southern China) and subjected to Illumina Hiseq sequencing of ITS1 genes. A total of 267 known genera and 90 known orders in 15 phyla were revealed in the mycobiomes. Ascomycota dominated all samples, followed by Basidiomycota and Mortierellomycota. The sediments possessed the relatively highest alpha diversity and were significantly different from weathered rocks according to the diversity indices and richness metrics. Fifteen families and eight genera with significant differences were detected in the sediment samples. The Ca/Mg ratio appeared to significantly affect the structure of the mycobiome communities. Ascomycota appeared to exert a controlling influence on the mycobiome co-occurrence network of the sediments, while Ascomycota and Basidiomycota were found to be the main phyla in the mycobiome co-occurrence network of weathered rocks. Our results provide a more comprehensive dimension to the mycobiome fingerprints of Luohandu cave and a new window into the mycobiome communities and the ecology of subterranean karst cave ecosystems.

18.
Inorg Chem ; 63(5): 2766-2775, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38253002

RESUMEN

The first hydride-doped Pd/Ag superatoms stabilized by selenolates are reported: [PdHAg19(dsep)12] [dsep = Se2P(OiPr)2] 1 and [PdHAg20(dsep)12]+ 2. 1 was derived from the targeted transformation of [PdHAg19(dtp)12] [dtp = S2P(OiPr)2] by ligand exchange, whereas 2 was obtained from the addition of trifluoroacetic acid to 1, resulting in a symmetric redistribution of the capping silver atoms. The transformations are all achieved while retaining an 8-electron superatomic configuration. VT-NMR attests to the good stability of the NCs in solution, and single-crystal X-ray diffraction reveals the crucial role that the interstitial hydride plays in directing the position of the capping silver atoms. The total structures are reported alongside their electronic and optical properties. 1 and 2 are phosphorescent with a lifetime of 73 and 84 µs at 77 K, respectively. The first antibacterial activity data for superatomic bimetallic Pd/Ag nanoclusters are also reported.

19.
Environ Res ; 241: 117632, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37967704

RESUMEN

BACKGROUND: Ozone (O3) exposure interrupts normal lung development in animal models. Epidemiologic evidence further suggests impairment with higher long-term O3 exposure across early and middle childhood, although study findings to date are mixed and few have investigated vulnerable subgroups. METHODS: Participants from the CANDLE study, a pregnancy cohort in Shelby County, TN, in the ECHO-PATHWAYS Consortium, were included if children were born at gestational age >32 weeks, completed a spirometry exam at age 8-9, and had a valid residential history from birth to age 8. We estimated lifetime average ambient O3 exposure based on each child's residential history from birth to age 8, using a validated fine-resolution spatiotemporal model. Spirometry was performed at the age 8-9 year study visit to assess Forced Expiratory Volume in the first second (FEV1) and Forced Vital Capacity (FVC) as primary outcomes; z-scores were calculated using sex-and-age-specific reference equations. Linear regression with robust variance estimators was used to examine associations between O3 exposure and continuous lung function z-scores, adjusted for child, sociodemographic, and home environmental factors. Potential susceptible subgroups were explored using a product term in the regression model to assess effect modification by child sex, history of bronchiolitis in infancy, and allergic sensitization. RESULTS: In our sample (n = 648), O3 exposure averaged from birth to age 8 was modest (mean 26.6 [SD 1.1] ppb). No adverse associations between long-term postnatal O3 exposure were observed with either FEV1 (ß = 0.12, 95% CI: -0.04, 0.29) or FVC (ß = 0.03, 95% CI: -0.13, 0.19). No effect modification by child sex, history of bronchiolitis in infancy, or allergic sensitization was detected for associations with 8-year average O3. CONCLUSIONS: In this sample with low O3 concentrations, we did not observe adverse associations between O3 exposures averaged from birth to age 8 and lung function in middle childhood.


Asunto(s)
Contaminantes Atmosféricos , Bronquiolitis , Ozono , Femenino , Embarazo , Humanos , Niño , Lactante , Contaminantes Atmosféricos/análisis , Pulmón , Capacidad Vital , Ozono/toxicidad , Ozono/análisis , Volumen Espiratorio Forzado , Exposición a Riesgos Ambientales
20.
J Am Chem Soc ; 146(1): 791-800, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38146836

RESUMEN

An understanding of the functional role played by a membrane-associated intrinsically disordered protein (IDP) requires characterization of its heterogeneous conformations as well as its poses relative to the membranes, which is of great interest but technically challenging. Here, we explore the membrane paramagnetic relaxation enhancement (mPRE) for constructing ensembles of IDPs that dynamically associate with membrane mimetics incorporating spin-labeled lipids. To accurately interpret the mPRE Γ2 rates, both the dynamics of IDPs and spin probe molecules are taken into account, with the latter described by a weighted three-dimensional (3D) grid model built based on all-atom simulations. The IDP internal conformations, orientations, and immersion depths in lipid bilayers are comprehensively optimized in the Γ2-based ensemble modeling. Our approach is tested and validated on the example of POPG bicelle-bound disordered cytoplasmic domain of CD3ε (CD3εCD), a component of the T-cell receptor (TCR) complex. The mPRE-derived CD3εCD ensemble provides new insights into the IDP-membrane fuzzy association, in particular for the tyrosine-based signaling motif that plays a critical role in TCR signaling. The comparative analysis of the ensembles for wild-type CD3εCD and mutants that mimic the mono- and dual-phosphorylation effects suggests a delicate membrane regulatory mechanism for activation and inhibition of the TCR activity.


Asunto(s)
Proteínas Intrínsecamente Desordenadas , Proteínas Intrínsecamente Desordenadas/metabolismo , Conformación Proteica , Marcadores de Spin , Receptores de Antígenos de Linfocitos T , Simulación de Dinámica Molecular
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