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1.
J Colloid Interface Sci ; 679(Pt A): 889-899, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39396464

RESUMEN

The performance of discharge plasma in treating organic pollutants and micro-organisms in water is impressive. When discharge plasma is used to treat polluted water containing organic pollutants and microorganisms, the presence of a certain amount of microplastics (MPs) in the water is unavoidable due to the complexity of the components contained in the water and the prevalence of MPs. MPs, as one of the pollutants that are difficult to be degraded by discharge plasma, undergo physical and chemical changes that increase their risk in the environment after treatment. Therefore, it is necessary to understand the fate of MPs after being treated with discharge plasma. In this study, the surface morphology of plastics before and after discharge plasma treatment was observed by scanning electron microscopy (SEM). The plastics after discharge plasma treatment were characterized by Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) to determine the changes in oxygen-containing functional groups on the surface. The recovery of microplastics (MPs) in saturated porous media under different physicochemical and plasma oxidation conditions was investigated by column experiments. It has been shown that MPs exhibit increased recovery under conditions of increased flow rate and pH. A decrease in recovery was observed at elevated ionic strength and co-existing cation valence. High voltages and low air flow rates increase the oxidation of MPs by increasing the thermal effects of the dielectric barrier discharge (DBD) plasma system, the amount of reactive oxygen species (ROS) and the intensity of ultraviolet ray (UV) irradiation. The mobility of MPs is enhanced by a combination of these factors. The advection-dispersion equation (ADE) fits the transport data of MPs well. The interaction energy between quartz sand and MPs was calculated using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. This study provides a new perspective on the potential risks of discharge plasma in water treatment.

2.
Environ Sci Technol ; 58(42): 18788-18799, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39374375

RESUMEN

With a growing emphasis on indoor air quality (IAQ) in educational environments, CO2 monitoring in classrooms has become commonplace. CO2 data can be used to estimate outdoor air change rate (ACH) based on the mass balance principle, which can be further linked to human health, performance, and building energy consumption. This study used a novel machine learning method to automatically segment CO2 concentration time series data into build-up, equilibrium, and decay periods, and then estimated classroom ACH using the corresponding CO2 mass balance equations. This method, applied to 40 classrooms in two mechanically ventilated K-6 schools, generated up to ten ACH estimates per day per classroom. A comparison with ACH calculated using the mechanical ventilation rates with 100% outdoor air reported by the building automation system during the study period reveals a slight underestimation by the decay and build-up methods, while the equilibrium method produced closer estimates. These differences may be attributed to uncertainties in occupancy, activity, CO2 emission rates, and air mixing. This research underscores the potential of leveraging CO2 data for more comprehensive IAQ assessments and highlights the challenges associated with accurately estimating ACH in real-world settings.


Asunto(s)
Contaminación del Aire Interior , Dióxido de Carbono , Monitoreo del Ambiente , Ventilación , Dióxido de Carbono/análisis , Monitoreo del Ambiente/métodos , Instituciones Académicas , Humanos
3.
BMC Pediatr ; 24(1): 522, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138455

RESUMEN

INTRODUCTION: Physical activity (PA) is believed to play an important part in many aspects during childhood and adolescence, especially cardiorespiratory fitness and cardiometabolic health. However, whether different levels of PA in daily life influence the structure or function of heart in school-aged children remains unknown. We aimed to investigate the association between PA and cardiovascular parameters in 7-year-old children. METHODS: Follow-up data from the Shanghai Prenatal Cohort Study and the Shanghai Birth Cohort was analyzed. Perinatal information including both maternal and offspring datum was recorded. A refined questionnaire was used to evaluate the frequency and duration of children's PA levels. Blood pressure, echocardiography, and anthropometry assessment were conducted during the follow-up of 7-year-old children. RESULTS: Overall, high PA level was associated with higher left ventricle posterior wall thickness in diastole (LVPWd, ß coefficient: 0.36, 95% CI: 0.12, 0.61), higher left ventricle mass index (LVMI, ß = 0.28, 95% CI: 0.07, 0.48), mitral E/a ratio (ß = 0.47, 95% CI: 0.22, 0.71) and slower heart rate (ß = -0.32, 95% CI: -0.57, -0.07), compared to low PA level. Medium PA level was associated with lower diastolic blood pressure (DBP, ß = -0.18, 95% CI: -0.35, -0.01). In subgroup analysis, increased relative wall thickness (RWT) was found in high PA level boys (ß = 0.36, 95% CI: 0.05, 0.67), and systolic blood pressure (SBP) showed a significant decrease in high PA level girls (ß = -0.42, 95% CI: -0.78, -0.06). CONCLUSIONS: This study suggested non-athlete children having higher PA level were associated with thicker left ventricle (LV) walls and better LV diastolic function, as well as slower heart rate and DBP at the age of 7. Furthermore, disparity in the association between PA level with morphological heart patterns and blood pressure existed in different sex category.


Asunto(s)
Presión Sanguínea , Ecocardiografía , Ejercicio Físico , Humanos , Femenino , Niño , Masculino , Estudios Transversales , China , Ejercicio Físico/fisiología , Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/anatomía & histología , Estudios de Seguimiento , Capacidad Cardiovascular/fisiología , Pueblos del Este de Asia
4.
Opt Lett ; 49(14): 4010-4013, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008764

RESUMEN

Polarization singularities that exist in momentum space have brought new opportunities in various fields such as enhanced optical nonlinearity, structured laser sources, and light field manipulation. However, previous researches have predominantly focused on the polarization singularities above the light line, because they have no leakage and are referred to bound states in the continuum. Here, by extending the polarization fields to Fourier components of the evanescent field on a dielectric metasurface, polarization singularities of different Fourier orders are discovered below the light line. When continuously changing the geometrical parameters of the metasurface, a Fourier order transition process of the polarization singularity is observed through the bandgap closing at the boundary of the Brillouin zone, which finally leads to the annihilation of two singularities with opposite topological charges below the light line. These findings expand the understanding of polarization singularities in the near-field region and may find applications in light field manipulation and light-matter interaction.

5.
IEEE Trans Neural Netw Learn Syst ; 35(9): 11857-11871, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38976472

RESUMEN

Designing new molecules is essential for drug discovery and material science. Recently, deep generative models that aim to model molecule distribution have made promising progress in narrowing down the chemical research space and generating high-fidelity molecules. However, current generative models only focus on modeling 2-D bonding graphs or 3-D geometries, which are two complementary descriptors for molecules. The lack of ability to jointly model them limits the improvement of generation quality and further downstream applications. In this article, we propose a joint 2-D and 3-D graph diffusion model (JODO) that generates geometric graphs representing complete molecules with atom types, formal charges, bond information, and 3-D coordinates. To capture the correlation between 2-D molecular graphs and 3-D geometries in the diffusion process, we develop a diffusion graph transformer (DGT) to parameterize the data prediction model that recovers the original data from noisy data. The DGT uses a relational attention mechanism that enhances the interaction between node and edge representations. This mechanism operates concurrently with the propagation and update of scalar attributes and geometric vectors. Our model can also be extended for inverse molecular design targeting single or multiple quantum properties. In our comprehensive evaluation pipeline for unconditional joint generation, the experimental results show that JODO remarkably outperforms the baselines on the QM9 and GEOM-Drugs datasets. Furthermore, our model excels in few-step fast sampling, as well as in inverse molecule design and molecular graph generation. Our code is provided in https://github.com/GRAPH-0/JODO.

6.
Environ Pollut ; 351: 124059, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703979

RESUMEN

The hazards of man-made chiral compounds are of great public concern, with reports of worrying stereoselective compounds and an urgent need to assess their transport. This study evaluated the transport of 2-arylpropionic acid derivatives enantiomers (2-APA) in porous media under a variety of solution chemistry conditions via column packing assays. The results revealed the introduction of Malic acid (MA) enantiomers enhanced the mobility of 2-APA enantiomers, but the enhancement effect was different for different 2-APA enantiomers. Batch sorption experiments confirmed that the MA enantiomers occupied the sorption site of the quartz sand, thus reducing the deposition of the 2-APA enantiomer. Homo- or heterochirality between 2-APA and MA dominates the transport of 2-APA enantiomers, with homochirality between them triggering stronger retention and vice versa. Further evaluating the effect of solution chemistry conditions on the transport of 2-APA enantiomers, increased ionic strength attenuated the mobility of 2-APA enantiomers, whereas introduced coexisting cations enhanced the retention of 2-APA enantiomers in the column. The redundancy analyses corroborated these solution chemistry conditions were negatively correlated with the transport of 2-APA enantiomers. The coupling of pH and these conditions reveals electrostatic forces dominate the transport behavior and stereoselective interactions of 2-APA enantiomers. Distinguishing the transport of enantiomeric pair helps to understand the difference in stereoselectivity of enantiomers and promises to remove the more hazardous one.


Asunto(s)
Propionatos , Estereoisomerismo , Propionatos/química , Porosidad , Adsorción , Malatos/química , Concentración de Iones de Hidrógeno
7.
Ecotoxicol Environ Saf ; 274: 116220, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38513531

RESUMEN

Previous research investigating the correlation between prenatal exposure to per- and polyfluoroalkyl substances (PFAS) and subsequent blood pressure (BP) in offspring has yielded limited and contradictory findings. This study was conducted to investigate the potential relationship between maternal PFAS levels during pregnancy and subsequent BP in early childhood. A total of 129 expectant mothers from the Shanghai Birth Cohort were included in the study. Using high-performance liquid chromatography/tandem mass spectrometry, we measured ten PFAS compounds in maternal plasma throughout the pregnancy. When the children reached the age of 4, we examined their systolic BP (SBP) and diastolic BP (DBP), along with mean arterial pressure (MAP) and pulse pressure (PP). Data interpretation employed multiple linear and logistic regression models, complemented by Bayesian kernel machine regression (BKMR).We found that the majority of PFAS concentrations remained stable during pregnancy. The linear and BKMR models indicated a positive relationship between the PFAS mixture in maternal plasma and offspring's DBP and MAP, with perfluorohexanesulphonic acid (PFHxS) having the most significant influence (PFHxS and DBP [first trimester:ß=3.03, 95%CI: (1.01,5.05); second trimester: ß=2.35, 95%CI: (0.94,3.75); third trimester: ß=2.57, 95%CI:(0.80,4.34)]; MAP [first trimester:ß=2.55, 95%CI: (0.64,4.45); second trimester: ß=2.28, 95%CI: (0.95,3.61); third trimester: ß=2.35, 95%CI:(0.68,4.01)]). Logistic regression highlighted an increased risk of prehypertension and hypertension in offspring with higher maternal PFHxS concentrations during all three trimesters [first trimester: OR=2.53, 95%CI:(1.11,5.79), second trimester: OR=2.05, 95%CI:(1.11,3.78), third trimester: OR=3.08, 95%CI:(1.40,6.79)]. A positive correlation was identified between the half-lives of PFAS and the odds ratio (OR) of prehypertension and hypertension in childhood (ß=0.139, P=0.010). In conclusion, this research found maternal plasma PFAS concentrations to be positively associated with BP in offspring, with PFHxS showing the most significant influence. This correlation remained consistent throughout pregnancy, and this effect was proportional to the half-lives of PFAS.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Hipertensión , Prehipertensión , Niño , Embarazo , Femenino , Humanos , Preescolar , Presión Sanguínea , Prehipertensión/inducido químicamente , Teorema de Bayes , Contaminantes Ambientales/toxicidad , Fluorocarburos/toxicidad , China , Hipertensión/inducido químicamente , Ácidos Alcanesulfónicos/toxicidad
8.
J Hazard Mater ; 468: 133824, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38377915

RESUMEN

The study examined the transport behavior of the 2-aryl propionic acid (2-APA) chiral pharmaceutical enantiomers by means of a laboratory-scale saturated quartz sand column experiment. Four typical of 2-APA and their enantiomers were selected for the study under different types of chiral organic acids (COAs)-mediated effects. Differences in the transport of the 2-APA enantiomeric pairs have been identified in response to various pH, types of COAs, and enantiomeric structures of COAs. Redundancy analysis identified the factors responsible for the largest differences in transport of 2-APA enantiomeric pairs, while spectroscopic characterization and density function theory (DFT) studies elucidated the underlying mechanisms contributing to the differences in transport of enantiomeric pairs. Obvious correlations among homochirality or heterochirality between COAs and 2-APA enantiomeric pairs were observed for changes in the mobility of 2-APA. The results indicate widespread COAs significantly affect the transport behavior of chiral man-made chemicals, suggesting more attention is needed to fill the gap in the perception of the transport behavior of chiral compounds.

9.
J Agric Food Chem ; 72(2): 1190-1202, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38175798

RESUMEN

10-Hydroxy-2-decenoic acid (10-HDA) is an important component of royal jelly, known for its antimicrobial, anti-inflammatory, blood pressure-lowering, and antiradiation effects. Currently, 10-HDA biosynthesis is limited by the substrate selectivity of acyl-coenzyme A dehydrogenase, which restricts the technique to a two-step process. This study aimed to develop an efficient and simplified method for synthesizing 10-HDA. In this study, ACOX from Candida tropicalis 1798, which catalyzes 10-hydroxydecanoyl coenzyme A desaturation for 10-HDA synthesis, was isolated and heterologously coexpressed with FadE, Macs, YdiI, and CYP in Escherichia coli/SK after knocking out FadB, FadJ, and FadR genes. The engineered E. coli/AKS strain achieved a 49.8% conversion of decanoic acid to 10-HDA. CYP expression was improved through ultraviolet mutagenesis and high-throughput screening, increased substrate conversion to 75.6%, and the synthesis of 10-HDA was increased to 0.628 g/L in 10 h. This is the highest conversion rate and product concentration achieved in the shortest time to date. This study provides a simple and efficient method for 10-HDA biosynthesis and offers an effective method for developing strains with high product yields.


Asunto(s)
Escherichia coli , Ácidos Grasos Monoinsaturados , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Grasos Monoinsaturados/metabolismo , Ácidos Grasos/metabolismo , Antiinflamatorios
10.
Environ Health ; 22(1): 72, 2023 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-37858165

RESUMEN

BACKGROUND: Humans are widely exposed to perfluoroalkyl substances (PFAS), which have been found to be associated with various adverse birth outcomes. As blood pressure (BP) is an important parameter reflecting cardiovascular health in early life, it is necessary to investigate the association of PFAS exposure during early lifetime and BP in childhood. Therefore, we investigated the potential association between PFAS levels in umbilical cord blood and BP of the offspring at 4 years of age in a prospective cohort study. METHODS: PFAS in umbilical cord blood samples after birth were measured with high-performance liquid chromatography/tandem mass spectrometry in the Shanghai Birth Cohort. BP was measured at 4 years of age in the offspring. Multiple linear regression model was used to investigate the association between individual PFAS level and BP of the offspring. Bayesian kernel machine regression (BKMR) was used to analyze the relationship between the PFAS mixture and BP of the offspring, while weighted quantile sum (WQS) regression was utilized for sensitivity analysis. RESULTS: A total of 129 mother-child pairs were included in our analysis. In multiple linear regressions, we observed that long-chain PFAS, mainly including perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (PFDA) and perfluoroundecanoic acid (PFUA), was negatively associated with systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MAP). BKMR showed that an increase in umbilical cord blood PFAS mixture levels was significantly associated with a decrease in SBP, DBP and MAP [Estimated differences (SD): -0.433 (0.161); -0.437 (0.176); -0.382 (0.179), respectively]. The most important component in the association with SBP, DBP, and MAP was PFUA. PFDoA was found to be positively associated with SBP, DBP and MAP in both models. Sensitivity analysis with WQS regression showed consistent results. CONCLUSION: Our findings suggested that umbilical blood PFAS exposure was negatively associated with BP in offspring at 4 years of age, including SBP, DBP, and MAP.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Humanos , Presión Sanguínea , Estudios Prospectivos , Sangre Fetal , Teorema de Bayes , China/epidemiología
11.
Analyst ; 148(19): 4857-4868, 2023 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-37624366

RESUMEN

Electrochemical sensing is ubiquitous in a number of fields ranging from biosensing, to environmental monitoring through to food safety and battery or corrosion characterisation. Whereas conventional potentiostats are ideal to develop assays in laboratory settings, they are in general, not well-suited for field work due to their size and power requirements. To address this need, a number of portable battery-operated potentiostats have been proposed over the years. However, most open source solutions do not take full advantage of integrated circuit (IC) potentiostats, a rapidly evolving field. This is partly due to the constraining requirements inherent to the development of dedicated interfaces, such as apps, to address and control a set of common electrochemical sensing parameters. Here we propose the PocketEC, a universal app that has all the functionalities to interface with potentiostat ICs through a user defined property file. The versatility of PocketEC, developed with an assay developer mindset, was demonstrated by interfacing it, via Bluetooth, to the ADuCM355 evaluation board, the open-source DStat potentiostat and the Voyager board, a custom-built, small footprint potentiostat based around the LMP91000 chip. The Voyager board is presented here for the first time. Data obtained using a standard redox probe, Ferrocene Carboxylic Acid (FCA) and a silver ion assay using anodic stripping multi-step amperometry were in good agreement with analogous measurements using a bench top potentiostat. Combined with its Voyager board companion, the PocketEC app can be used directly for a number of wearable or portable electrochemical sensing applications. Importantly, the versatility of the app makes it a candidate of choice for the development of future portable potentiostats. Finally, the app is available to download on the Google Play store and the source codes and design files for the PocketEC app and the Voyager board are shared via Creative Commons license (CC BY-NC 3.0) to promote the development of novel portable or wearable applications based on electrochemical sensing.

12.
Nanoscale Horiz ; 8(10): 1403-1410, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37482887

RESUMEN

All-inorganic cesium lead bromide (CsPbBr3) quantum dots (QDs) with high photoluminescence (PL) quantum efficiency have been reported as ideal gain materials for high-performance lasers. Nevertheless, isolated CsPbBr3 QDs have not achieved lasing emission (LE) due to finite absorption cross-section. Here, we demonstrate continuous-wave lasing of isolated CsPbBr3 QDs embedded in a microcavity. Distributed Bragg reflectors (DBRs), together with isolated CsPbBr3 QDs in a polymer matrix, are introduced to construct a vertical-cavity surface-emitting laser (VCSEL), which exhibits stable single-mode lasing emissions with an ultra-low threshold of 8.8 W cm-2 and a high Q factor of 1787. Such perovskite-based microcavity structures sustain highly stable excitons at room temperature and can provide an excellent experimental platform to further study the single-particle nano-lasers and quantum physics frontiers such as exciton-polariton condensation, single-photon emission, and optical quantum communication.

13.
Front Bioeng Biotechnol ; 11: 1194511, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324439

RESUMEN

Background: L-lysine is widely used in the feed, food, and pharmaceutical industries, and screening for high L-lysine-producing strains has become a key goal for the industry. Methods: We constructed the rare L-lysine codon AAA by corresponding tRNA promoter replacement in C. glutamicum. Additionally, a screening marker related to the intracellular L-lysine content was constructed by converting all L-lysine codons of enhanced green fluorescent protein (EGFP) into the artificial rare codon AAA. The artificial EGFP was then ligated into pEC-XK99E and transformed into competent Corynebacterium glutamicum 23604 cells with the rare L-lysine codon. After atmospheric and room-temperature plasma mutation and induction culture, 55 mutants (0.01% of total cells) with stronger fluorescence were sorted using flow cytometry, and further screened by fermentation in a 96-deep-well plate and 500 mL shaker. Results: The fermentation results showed that the L-lysine production was increased by up to 9.7% in the mutant strains with higher fluorescence intensities, and that the highest screening positive rate was 69%, compared with that in the wild-type strain. Conclusion: The application of artificially constructed rare codons in this study represents an efficient, accurate, and simple method for screening other amino acid-producing microorganisms.

14.
Environ Sci Technol ; 57(27): 10030-10038, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37378593

RESUMEN

Low-cost air quality monitors are increasingly being deployed in various indoor environments. However, data of high temporal resolution from those sensors are often summarized into a single mean value, with information about pollutant dynamics discarded. Further, low-cost sensors often suffer from limitations such as a lack of absolute accuracy and drift over time. There is a growing interest in utilizing data science and machine learning techniques to overcome those limitations and take full advantage of low-cost sensors. In this study, we developed an unsupervised machine learning model for automatically recognizing decay periods from concentration time series data and estimating pollutant loss rates. The model uses k-means and DBSCAN clustering to extract decays and then mass balance equations to estimate loss rates. Applications on data collected from various environments suggest that the CO2 loss rate was consistently lower than the PM2.5 loss rate in the same environment, while both varied spatially and temporally. Further, detailed protocols were established to select optimal model hyperparameters and filter out results with high uncertainty. Overall, this model provides a novel solution to monitoring pollutant removal rates with potentially wide applications such as evaluating filtration and ventilation and characterizing indoor emission sources.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminantes Ambientales , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Monitoreo del Ambiente/métodos , Análisis por Conglomerados , Contaminación del Aire Interior/análisis
15.
Front Bioeng Biotechnol ; 11: 1202483, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37334270

RESUMEN

Introduction: ß-Alanine is the only ß-amino acid in nature; it is widely used in food additives, medicines, health products, and surfactants. To avoid pollution caused by traditional production methods, the synthesis of ß-alanine has been gradually replaced by microbial fermentation and enzyme catalysis, which is a green, mild, and high-yield biosynthesis method. Methods: In this study, we constructed an Escherichia coli recombinant strain for efficient ß-alanine production using glucose as the raw material. The microbial synthesis pathway of L-lysine-producing strain, Escherichia coli CGMCC 1.366, was modified using gene editing by knocking out the aspartate kinase gene, lysC. The catalytic efficiency and product synthesis efficiency were improved by assembling key enzymes with cellulosome. Results: By-product accumulation was reduced by blocking the L-lysine production pathway, thereby increasing the yield of ß-alanine. In addition, catalytic efficiency was improved by the two-enzyme method to further increase the ß-alanine content. The key cellulosome elements, dockerin (docA) and cohesin (cohA), were combined with L-aspartate-α-decarboxylase (bspanD) from Bacillus subtilis and aspartate aminotransferase (aspC) from E.coli to improve the catalytic efficiency and expression level of the enzyme. ß-alanine production reached 7.439 mg/L and 25.87 mg/L in the two engineered strains. The ß-alanine content reached 755.465 mg/L in a 5 L fermenter. Discussion: The content of ß-alanine synthesized by constructed ß-alanine engineering strains were 10.47 times and 36.42 times higher than the engineered strain without assembled cellulosomes, respectively. This research lays the foundation for the enzymatic production of ß-alanine using a cellulosome multi-enzyme self-assembly system.

16.
Sci Adv ; 9(23): eadf0284, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-37285430

RESUMEN

It is known that post-retrieval extinction but not extinction alone could erase fear memory. However, whether the coding pattern of original fear engrams is remodeled or inhibited remains largely unclear. We found increased reactivation of engram cells in the prelimbic cortex and basolateral amygdala during memory updating. Moreover, conditioned stimulus- and unconditioned stimulus-initiated memory updating depends on the engram cell reactivation in the prelimbic cortex and basolateral amygdala, respectively. Last, we found that memory updating causes increased overlapping between fear and extinction cells, and the original fear engram encoding was altered during memory updating. Our data provide the first evidence to show the overlapping ensembles between fear and extinction cells and the functional reorganization of original engrams underlying conditioned stimulus- and unconditioned stimulus-initiated memory updating.


Asunto(s)
Complejo Nuclear Basolateral , Memoria , Memoria/fisiología , Miedo/fisiología , Condicionamiento Clásico/fisiología , Condicionamiento Operante
17.
Chemosphere ; 331: 138789, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37116726

RESUMEN

Assessing the impact of chemical contaminants on aquatic ecosystem health remains challenging due to complex exposure scenarios and the myriad of impact metrics to consider. To expand the breadth of compounds monitored and evaluate the potential hazard of environmental mixtures, cell-based bioassays (estrogen receptor alpha (ERα) and aryl hydrocarbon receptor (AhR)) and non-targeted chemical analyses with high resolution mass spectrometry (NTA-HRMS) were used to assess the quality of ∼70 marine sediment samples collected from 5 distinct coastal and offshore habitats of the Southern California Bight. AhR responses (<0.12-4.5 ng TCDD/g dry weight) were more frequently detectable and more variable than for ERα (<0.1-0.5 ng E2/g dry weight). The range of AhR and ERα responses increased by habitat as follows: Channel Islands < Mid-shelf < Marinas < Ports < Estuaries. The narrow range and magnitude of ERα screening response suggested limited potential for estrogenic impacts across sediments from all 5 habitats. The AhR response was positively correlated with total PAH and PCB concentrations and corresponded with a chemical score index representing the severity of metal and organic contamination. NTA-HRMS fingerprints generated in positive electrospray ionization mode were clearly distinguishable among coastal vs. offshore samples, with the greatest chemical complexity (n = 982 features detected) observed in estuarine sediment from a highly urbanized watershed (Los Angeles River). The concordance and complementary nature of bioscreening and NTA-HRMS results indicates their utility as holistic proxies for sediment quality, and when analyzed in conjunction with routine targeted chemical monitoring, show promise in identifying unexpected contaminants and novel toxicants.


Asunto(s)
Monitoreo del Ambiente , Contaminantes Químicos del Agua , California , Ecosistema , Monitoreo del Ambiente/métodos , Receptor alfa de Estrógeno , Cromatografía de Gases y Espectrometría de Masas , Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis
18.
BMC Med ; 21(1): 103, 2023 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-36941582

RESUMEN

BACKGROUND: Current evidence relating birthweight and gestational age to cardiovascular risk is conflicting. Whether these factors have independent or interactive impacts on cardiovascular parameters during early childhood remains unclear. The goal of this study was to explore whether there were any independent and interactive effects of gestational age and birthweight on blood pressure, left ventricle (LV) structure, and function in 4 years old. METHODS: This study included 1194 children in the Shanghai Birth Cohort from 2013 to 2016. Information about the mothers and children was recorded at time of birth using a questionnaire. Follow-up measurements, including anthropometric, blood pressure, and echocardiography, were taken between 2018 and 2021, when the children were 4 years old. Multiple linear or logistic regressions and restricted cubic spline were used to explore the association of birthweight and gestational age with cardiovascular measurements. RESULTS: Gestational age had a significant negative correlation with both systolic blood pressure [ß = - 0.41, 95% CI: (- 0.76, - 0.07)] and mean arterial pressure [ß = - 0.36, 95%CI: (- 0.66, - 0.07)]. The risk of prehypertension decreased with increased gestational age [OR = 0.54, 95% CI: (0.32, 0.93)]. The relationship between birthweight with blood pressure was U-shape (P for non-linear < 0.001). The wall thickness, volume, mass, and cardiac output of LV increased with birthweight, though the ejection fraction [ß = - 1.02, 95% CI: (- 1.76, - 0.27)] and shorten fraction [ß = 0.72, 95% CI: (- 1.31, - 0.14)] decreased with birthweight. The risk of LV hypertrophy was not associated with birthweight [OR = 1.59, 95% CI: (0.68, 3.73)]. CONCLUSIONS: In this study, we found different associations of birthweight and gestational age with cardiovascular measurements in the offspring at 4 years old. Gestational age influenced blood pressure independent of birthweight. Heart size and function at 4 years old was influenced mostly by birthweight and not by gestational age.


Asunto(s)
Peso al Nacer , Niño , Femenino , Humanos , Preescolar , Presión Sanguínea , Estudios de Cohortes , Edad Gestacional , Estudios Prospectivos , China
19.
J Nutr ; 153(1): 190-196, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36913453

RESUMEN

BACKGROUND: Maternal hyperglycemia has been associated with cardiovascular disease risks in offspring. Previous studies were mostly conducted to test this association in pregnancies with (pre)gestational diabetes mellitus. However, the association may not be limited to populations with diabetes only. OBJECTIVES: The aim of this study was to assess the association between gestational glucose concentrations in women without (pre)gestational diabetes mellitus and childhood cardiovascular alterations at the age of 4 y. METHODS: Our study was based on the Shanghai Birth Cohort. Briefly, among 1016 nondiabetic mothers (age: 30.8 ± 3.42 y; BMI: 21.3 ± 2.94) and their offsprings (age: 4.41 ± 0.22 y; BMI: 15.0 ± 1.56; 53.0% males), results of maternal 1-h oral OGTT between 24 and 28 gestational weeks were obtained. Childhood blood pressure (BP) measurement, echocardiography, and vascular ultrasound were performed at 4 y old. Linear regression and binary logistic regression were conducted to test the association between maternal glucose and childhood cardiovascular outcomes. RESULTS: Compared with children from mothers with glucose concentrations in the lowest quartile, children from mothers in the highest quartile had higher BP (systolic: 97.0 ± 7.41 compared with 98.9 ± 7.82 mmHg, P = 0.006; diastolic: 56.8 ± 5.83 compared with 57.9 ± 6.03 mmHg, P = 0.051) and lower left ventricular ejection fraction (92.5 ± 9.15 compared with 90.8 ± 9.16 %, P = 0.046). Also, higher maternal OGTT 1-h glucose concentrations across the full range were associated with higher childhood BP (systolic: ß: 0.56; 95% CI: 0.19, 0.93; diastolic: ß: 0.36; 95% CI: 0.05, 0.66). Logistic regression showed, compared with children from mothers in the lowest quartile, children from mothers in the highest quartile had a 58% (OR=1.58; 95% CI: 1.01, 2.47) higher odds of elevated systolic BP (≥90th percentile). CONCLUSIONS: In a population without (pre)gestational diabetes mellitus, higher maternal OGTT 1-h glucose were associated with childhood cardiovascular structure and function alterations. Further studies are needed to assess whether interventions to reduce gestational glucose will mitigate subsequent cardiometabolic risks in offspring.


Asunto(s)
Diabetes Gestacional , Hipertensión , Embarazo , Masculino , Niño , Humanos , Preescolar , Femenino , Adulto , Estudios de Cohortes , Estudios Prospectivos , Volumen Sistólico , Función Ventricular Izquierda , China , Glucosa
20.
Environ Int ; 173: 107748, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36848830

RESUMEN

BACKGROUND: High maternal plasma perfluoroalkyl substances (PFAS) concentrations has been associated with adverse birth outcomes, but data on early childhood cardiovascular health is limited. This study aimed to assess the potential association between maternal plasma PFAS concentrations during early pregnancy and cardiovascular development in offspring. MATERIAL AND METHODS: Cardiovascular development was assessed through blood pressure measurement, echocardiography and carotid ultrasound examinations among 957 children from the Shanghai Birth Cohort aged at 4 years old. Maternal plasma concentrations of PFAS were measured at mean gestational age of 14.4 (SD:1.8) weeks. The joint associations between PFAS mixture concentrations and cardiovascular parameters were analyzed using a Bayesian kernel machine regression (BKMR). The potential association of individual PFAS chemicals concentrations was explored using multiple linear regression. RESULTS: In BKMR analyses, carotid intima media thickness (cIMT), interventricular septum thickness in diastole and systole, posterior wall thicknesses in diastole and systole, and relative wall thickness were significantly lower when all log10-transformed PFAS were fixed at 75th percentile in comparison to at their 50th percentile[Estimated overall Risk:-0.31 (95%CI: -0.42, -0.20), -0.09 (95%CI: -0.11, -0.07), -0.21 (95%CI: -0.26, -0.16), -0.09 (95%CI: -0.11, -0.07), -0.07 (95%CI: -0.10, -0.04) and -0.005 (95%CI: -0.006, -0.004)].Furthermore, maternal plasma concentrations of individual short-chain PFAS was associated with a decrease in left ventricular wall thickness, intraventricular septum thickness and enlarged chamber volume, and long-chain with a decrease in cIMT. CONCLUSIONS: Our findings suggest that maternal plasma PFAS concentrations during early pregnancy was adversely associated with cardiovascular development in offspring, including thinner cardiac wall thickness and cIMT.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Embarazo , Niño , Femenino , Humanos , Preescolar , Anciano , Lactante , Exposición Materna/efectos adversos , Estudios Prospectivos , Teorema de Bayes , Grosor Intima-Media Carotídeo , Contaminantes Ambientales/efectos adversos , Fluorocarburos/efectos adversos , China
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