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1.
Nature ; 627(8002): 42-43, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418722
2.
Clin Immunol ; 259: 109879, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38142901

RESUMO

The impact of Omicron infections on the clinical outcome and immune responses of myasthenia gravis (MG) remained largely unknown. From a prospective multicenter MG cohort (n = 189) with 197 myasthenic crisis (MC), we finally included 41 independent MG patients to classify into two groups: the Omicron Group (n = 13) and the Control Group (n = 28). In this matched cohort study, all-cause mortality was 7.69% (1/13) in Omicron Group and 14.29% (4/28) in Control Group. A higher proportion of elevated serum IL-6 was identified in the Omicron Group (88.89% vs 52.38%, P = 0.049). In addition, the proportions of CD3+CD8+T in lymphocytes and Tregs in CD3+CD4+ T cells were significantly elevated in the Omicron Group (both P = 0.0101). After treatment, the Omicron Group exhibited a marked improvement in MG-ADL score (P = 0.026) and MG-QoL-15 (P = 0.0357). MCs with Omicron infections were associated with elevated serum IL-6 and CD3+CD8+T response. These patients tended to present a better therapeutic response after fast-acting therapies and anti-IL-6 treatment.


Assuntos
Interleucina-6 , Miastenia Gravis , Humanos , Estudos Prospectivos , Estudos de Coortes , Qualidade de Vida , Miastenia Gravis/tratamento farmacológico
3.
Pediatr Res ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39154142

RESUMO

BACKGROUND: Few studies have estimated the associations of systemic inflammation markers and high blood pressure (HBP) in the pediatric population. METHODS: Basing on data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, we assessed the associations between four inflammation-related factors based on blood cell counts: systemic immune inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and risk for pediatric HBP by estimating odds ratios (ORs) using multivariable logistic regression models. RESULTS: A total of 17,936 children aged 8-19 years were included in the analysis, representing about 36.7 million American children. The prevalence rates of elevated blood pressure (EBP) and hypertension (HTN) were 15.79% and 6.77%, respectively. The results showed that the ORs for EBP per standard deviation (SD) increment in SII and NLR were estimated at 1.11 [95% confidence interval (95%CI): 1.04, 1.17] and 1.08 (95%CI: 1.02, 1.15), respectively; and the OR for EBP per SD increment in LMP were estimated at 0.90 (95%CI: 0.83, 0.96). These associations were stronger in boys and younger children. CONCLUSIONS: The study suggested that inflammation-related factors could serve as easily accessible early biomarkers for HBP risk prediction and prevention in children and adolescents. IMPACT: The study suggested that inflammation-related factors could serve as easily accessible early biomarkers for HBP risk prediction and prevention in children and adolescents. This is the first study that demonstrates the close association between systemic inflammation markers and HBP in children and adolescents using nationally representative population data. The findings have more public health implications and support that systemic inflammation markers based on blood cell counts could serve as easily accessible biomarkers of HBP risk and prevention in earlier identification of the diseases.

4.
Ecotoxicol Environ Saf ; 277: 116339, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38669873

RESUMO

Children's exposures to environmental antibiotics are a major public health concern. However, limited data are available on the effects of environmental antibiotic exposures on childhood obesity. Our study aimed to explore this relationship. We conducted a cross-sectional case-control study nested in a population-based survey of primary school students, including 1855 obese and 1875 random selected control children. A total of 10 antibiotics in urine samples were measured by liquid chromatography-tandem mass spectrometry. Multivariable survey logistic regression was used to assess the associations between environmental antibiotics exposures and childhood obesity. After adjusting for potential confounders, increased odds of obesity were observed in children exposed to tetracycline (OR = 1.31, 95% CI: 1.09-1.57) and sulfamonomethoxine (OR = 1.43, 95% CI: 1-2.05). Comparing none (

Assuntos
Antibacterianos , Exposição Ambiental , Obesidade Infantil , Humanos , Estudos de Casos e Controles , Antibacterianos/efeitos adversos , Masculino , Criança , Estudos Transversais , Feminino , Exposição Ambiental/estatística & dados numéricos , Obesidade Infantil/epidemiologia , Obesidade Infantil/induzido quimicamente , Poluentes Ambientais/urina , Modelos Logísticos
5.
Matern Child Nutr ; : e13685, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886166

RESUMO

Iodine, an essential trace element for the human body, plays a pivotal role in sustaining health. Malnutrition has emerged as a pressing public health concern, posing a significant threat to human well-being. Iodine deficiency poses a substantial threat to the development of children, potentially leading to neurological developmental disorders and mental retardation. Conversely, excessive iodine intake can result in structural and functional abnormalities in the thyroid gland. In this study, we selected children aged 3-6 years through a stratified cluster sampling approach in six regions across China to explore the correlation between iodine nutrition and their physical growth. A total of 5920 preschool children participated in this study, with a median urinary iodine concentration (UIC) of 177.33 [107.06, 269.92] µg/L. Among these children, 250 (4.2%) exhibited stunting, 180 (3.0%) were underweight, 198 (3.3%) experienced wasting, 787 (3.3%) were overweight and 414 (7.0%) were classified as obese. The multivariate linear regression revealed that UIC exhibited a positive correlation with body mass index z-Score (BMIZ) in overweight children (ß = 0.038; 95% CI: 0.001, 0.075). In normally growing children, the associations between UIC and height-for-age z-score, weight-for-age z-score and BMIZ displayed nonlinear patterns. Our findings suggest that iodine nutrition is adequate for Chinese children aged 3-6 years. Furthermore, iodine nutrition is intricately linked to the growth and development of these children. Consequently, it is imperative to implement decisive measures to prevent both iodine deficiency and excess.

6.
Angew Chem Int Ed Engl ; : e202406054, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980317

RESUMO

Electrochemical impedance spectroscopy (EIS), characterized by its non-destructive and in-situ nature, plays a crucial role in comprehending the thermodynamic and kinetic processes occurring with Li-ion batteries. However, there is a lack of consistent and coherent physical interpretations for the EIS of porous electrodes. Therefore, it is imperative to conduct thorough investigations into the underlying physical mechanisms of EIS. Herein, by employing reference electrode in batteries, we revisit the associated physical interpretation of EIS at different frequency. Combining different battery configurations, temperature-dependent experiments, and elaborated distribution of relaxation time analysis, we find that the ion transport in porous electrode channels and pseudo-capacitance behavior dominate the high-frequency and mid-frequency impedance arcs, respectively. This work offers a perspective for the physical interpretation of EIS and also sheds light on the understanding of EIS characteristics in other advanced energy storage systems.

7.
Angew Chem Int Ed Engl ; 63(19): e202317856, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38389190

RESUMO

In solid-state lithium metal batteries (SSLMBs), the inhomogeneous electrolyte-electrode interphase layer aggravates the interfacial stability, leading to discontinuous interfacial ion/charge transport and continuous degradation of the electrolyte. Herein, we constructed an anion-modulated ionic conductor (AMIC) that enables in situ construction of electrolyte/electrode interphases for high-voltage SSLMBs by exploiting conformational transitions under multiple interactions between polymer and lithium salt anions. Anions modulate the decomposition behavior of supramolecular poly (vinylene carbonate) (PVC) at the electrode interface by changing the spatial conformation of the polymer chains, which further enhances ion transport and stabilizes the interfacial morphology. In addition, the AMIC weakens the "Li+-solvation" and increases Li+ vehicle sites, thereby enhancing the lithium-ion transport number (tLi +=~0.67). Consequently, Li || LiNi0.8Co0.1Mn0.1O2 cell maintains about 85 % capacity retention and Coulombic efficiency >99.8 % in 200 cycles at a charge cut-off voltage of 4.5 V. This study provides a new understanding of lithium salt anions regulating polymer chain segment behavior in the solid-state polymer electrolyte (SPE) and highlights the importance of the ion environment in the construction of interfacial phases and ionic conduction.

8.
Angew Chem Int Ed Engl ; : e202407075, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990170

RESUMO

Sodium metal batteries (SMBs) have received increasing attention due to the abundant sodium resources and high energy density, but suffered from the sluggish interfacial kinetic and unstable plating/stripping of sodium anode at low temperature, especially when matched with ester electrolytes. Here, we develop a stable ultra-low-temperature SMBs with high-capacity retention at -50°C in a weak solvated carbonate ester-based electrolyte, combined with an electrodeposited Na (Cu/Na) anode. The Cu/Na anode with electrochemically activated "deposited sodium" and stable inorganic-rich solid electrolyte interphase (SEI) was favor for the fast Na+ migration, therefore accelerating the interfacial kinetic process. As a result, the Cu/Na || NaCrO2 battery exhibited the highest capacity retention (compared to room-temperature capacity) in carbonate ester-based SMBs (98.05% at -25°C, 91.3% at -40°C, 87.9% at -50°C, respectively). The cyclic stability of 350 cycles at -25°C with a high energy efficiency of 96.15% and 70 cycles at -50°C can be achieved. Even in chill atmospheric environment with the fluctuant temperature, the battery can still operate over one month. This work provides a new opportunity for the development of low-temperature carbonate ester-based SMBs.

9.
Angew Chem Int Ed Engl ; : e202409409, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39008227

RESUMO

Lithium iron phosphate (LFP)/graphite batteries have long dominated the energy storage battery market and are anticipated to become the dominant technology in the global power battery market. However, the poor fast-charging capability and low-temperature performance of LFP/graphite batteries seriously hinder their further spread. These limitations are strongly associated with the interfacial Li-ion transport. Here we report a wide-temperature-range ester-based electrolyte that exhibits high ionic conductivity, fast interfacial kinetics and excellent film-forming ability by regulating the anion chemistry of Li salt. The interfacial barrier of the battery is quantitatively unraveled by employing three-electrode system and distribution of relaxation time technique. The superior role of the proposed electrolyte in preventing Li0 plating and sustaining homogeneous and stable interphases are also systematically investigated. The LFP/graphite cells exhibit rechargeability in an ultrawide temperature range of -80°C to 80°C and outstanding fast-charging capability without compromising lifespan. Specially, the practical LFP/graphite pouch cells achieve 80.2% capacity retention after 1200 cycles (2 C) and 10-min charge to 89% (5 C) at 25°C and provides reliable power even at -80°C.

10.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(7): 765-773, 2024 Jul 15.
Artigo em Zh | MEDLINE | ID: mdl-39014955

RESUMO

OBJECTIVES: To investigate the role and mechanism of epithelial-mesenchymal transition (EMT) in a rat model of bronchopulmonary dysplasia (BPD). METHODS: The experiment consisted of two parts. (1) Forty-eight preterm rats were randomly divided into a normoxia group and a hyperoxia group, with 24 rats in each group. The hyperoxia group was exposed to 85% oxygen to establish a BPD model, while the normoxia group was kept in room air at normal pressure. Lung tissue samples were collected on days 1, 4, 7, and 14 of the experiment. (2) Rat type II alveolar epithelial cells (RLE-6TN) were randomly divided into a normoxia group (cultured in air) and a hyperoxia group (cultured in 95% oxygen), and cell samples were collected 12, 24, and 48 hours after hyperoxia exposure. Hematoxylin-eosin staining was used to observe alveolarization in preterm rat lungs, and immunofluorescence was used to detect the co-localization of surfactant protein C (SPC) and α-smooth muscle actin (α-SMA) in preterm rat lung tissue and RLE-6TN cells. Quantitative real-time polymerase chain reaction and protein immunoblotting were used to detect the expression levels of EMT-related mRNA and proteins in preterm rat lung tissue and RLE-6TN cells. RESULTS: (1) Compared with the normoxia group, the hyperoxia group showed blocked alveolarization and simplified alveolar structure after 7 days of hyperoxia exposure. Co-localization of SPC and α-SMA was observed in lung tissue, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 7 and 14 days of hyperoxia exposure compared to the normoxia group. In the hyperoxia group, the mRNA and protein levels of TGF-ß1, α-SMA, and N-cadherin were increased, while the mRNA and protein levels of SPC and E-cadherin were decreased at 7 and 14 days of hyperoxia exposure compared to the normoxia group (P<0.05). (2) SPC and α-SMA was observed in RLE-6TN cells, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 24 and 48 hours of hyperoxia exposure compared to the normoxia group. Compared to the normoxia group, the mRNA and protein levels of SPC and E-cadherin in the hyperoxia group were decreased, while the mRNA and protein levels of TGF-ß1, α-SMA, and E-cadherin in the hyperoxia group increased at 48 hours of hyperoxia exposure (P<0.05). CONCLUSIONS: EMT disrupts the tight connections between alveolar epithelial cells in a preterm rat model of BPD, leading to simplified alveolar structure and abnormal development, and is involved in the development of BPD. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 765-773.


Assuntos
Displasia Broncopulmonar , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal , Hiperóxia , Ratos Sprague-Dawley , Animais , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/patologia , Displasia Broncopulmonar/metabolismo , Hiperóxia/complicações , Ratos , Actinas/análise , Actinas/metabolismo , Actinas/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/análise , Animais Recém-Nascidos , Feminino , Proteína C Associada a Surfactante Pulmonar/genética , Pulmão/patologia , Pulmão/metabolismo , Masculino
11.
J Am Chem Soc ; 145(14): 8001-8006, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36988463

RESUMO

The solid electrolyte interphase (SEI) is regarded as the most important yet least understood component in Li-ion batteries. Considerable effort has been devoted to unravelling its chemistry, structure, and ion-transport mechanism; however, the nucleation and growth mode of SEI, which underlies all these properties, remains the missing piece. We quantify the growth mode of two representative SEIs on carbonaceous anodes based on classical nucleation theories and in situ atomic force microscopy imaging. The formation of inorganic SEI obeys the mixed 2D/3D growth model and is highly dependent on overpotential, whereby large overpotential favors 2D growth. Organic SEI strictly follows the 2D instantaneous nucleation and growth model regardless of overpotential and enables perfect epitaxial passivation of electrodes. We further demonstrate the use of large current pulses during battery formation to promote 2D inorganic SEI growth and improve capacity retention. These insights offer the potential to tailor desired interphases at the nanoscale for future electrochemical devices.

12.
J Transl Med ; 21(1): 564, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37620910

RESUMO

BACKGROUND: Myasthenia gravis (MG) is the most prevalent autoimmune disorder affecting the neuromuscular junction. A rapid deterioration in respiratory muscle can lead to a myasthenic crisis (MC), which represents a life-threatening condition with high mortality in MG. Multiple CD4+ T subsets and hypercytokinemia have been identified in the peripheral pro-inflammatory milieu during the crisis. However, the pathogenesis is complicated due to the many types of cells involved, leaving the underlying mechanism largely unexplored. METHODS: We conducted single-cell transcriptomic and immune repertoire sequencing on 33,577 peripheral blood mononuclear cells (PBMCs) from two acetylcholine receptor antibody-positive (AChR +) MG patients during MC and again three months post-MC. We followed the Scanpy workflow for quality control, dimension reduction, and clustering of the single-cell data. Subsequently, we annotated high-resolution cell types utilizing transfer-learning models derived from publicly available single-cell immune datasets. RNA velocity calculations from unspliced and spliced mRNAs were applied to infer cellular state progression. We analyzed cell communication and MG-relevant cytokines and chemokines to identify potential inflammation initiators. RESULTS: We identified a unique subset of monocytes, termed monocytes 3 (FCGR3B+ monocytes), which exhibited significant differential expression of pro-inflammatory signaling pathways during and after the crisis. In line with the activated innate immune state indicated by MC, a high neutrophil-lymphocyte ratio (NLR) was confirmed in an additional 22 AChR + MC patients in subsequent hemogram analysis and was associated with MG-relevant clinical scores. Furthermore, oligoclonal expansions were identified in age-associated B cells exhibiting high autoimmune activity, and in CD4+ and CD8+ T cells demonstrating persistent T exhaustion. CONCLUSIONS: In summary, our integrated analysis of single-cell transcriptomics and TCR/BCR sequencing has underscored the role of innate immune activation which is associated with hypercytokinemia in MC. The identification of a specific monocyte cluster that dominates the peripheral immune profile may provide some hints into the etiology and pathology of MC. However, future functional studies are required to explore causality.


Assuntos
Síndrome da Liberação de Citocina , Miastenia Gravis , Humanos , Transcriptoma/genética , Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Miastenia Gravis/genética
13.
Opt Express ; 31(16): 25815-25828, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710457

RESUMO

The vertical profile of optical turbulence is a key factor in the performance design of astronomical telescopes and adaptive optics instruments. As site-testing campaigns are extremely expensive, the selection of appropriate spatial resolution data and estimation methods is extremely important. This study investigated the effect of using different methods (Dewan, HMNSP99, Thorpe method) to estimate the refractive index structure constant (C n2) using different resolution data (5 m, 25 m, ERA5 data) in Huaihua, Hunan. Compared with Dewan, HMNSP99 for estimating C n2 using 5 m and 25 m resolution data, the Thorpe method almost always shows the best performance, with RXY above 0.75 and lower RMSE and MRE between estimated and measured C n2. The results of C n2 estimation using HMNSP99 at different resolution data varied widely, indicating that HMNSP99 is more sensitive to the data resolution and the temperature gradient is more sensitive to the resolution. Using ERA5 data, the two methods of estimating C n2 using Dewan and HMNSP99 have close results. It indicates that the wind shear is the main factor when the spatial resolution of the data is reduced to a certain degree, and the contribution of temperature gradient is small in the high altitude turbulence.

14.
Inorg Chem ; 62(5): 2236-2243, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36689619

RESUMO

Two zero-dimensional inorganic-organic hybrids, namely, [C4mim][Cd(TCDPPA)3] (1) and [C4mpy][Cd(TCDPPA)3] (2), where (TCDPPA)- = 2,2,2-trichloro-N-(di(pyrrolidin-1-yl)phosphoryl)acetamide, (C4mim)+ = 1-butyl-3-methylimidazolium, and (C4mpy)+ = 1-butyl-4-methylpyridinium, have been synthesized via metathesis reactions and characterized systematically. These ionic cadmium-containing inorganic-organic hybrid compounds are assembled from a bulky organic cation and a complex anion constructed from the chelation of three TCDPPA ligands to one cadmium ion. These compounds possess wide band gaps and emit in the deep-blue region intensely with a quantum yield as high as 34.04%. The success of this work provides a new method for the design and fabrication of high-efficiency blue-emitting materials.

15.
Ecotoxicol Environ Saf ; 262: 115326, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37556958

RESUMO

Manganese (Mn) is an essential trace element that maintains many normal physiological functions. However, multi-system disorders would occur once overexposure to Mn, especially neurotoxicity. Despite evidence demonstrating the critical role of ROS-activated JNK/FOXO3a signaling pathway in neuronal survival, the specific mechanisms by which it contributes to Mn-induced neurotoxicity are still unclear. The objectives of this study was to examine the modulation of the JNK/FOXO3a signaling pathway, which is activated by ROS, in Mn-induced apoptosis, using a rat brain astrocyte cell line (CTX cells). This study found that a dose-dependent decrease in cell viability of CTX cells was observed with 150, 200, 250, 300 µmol/L Mn. The results of apoptosis-related protein assay showed that Mn decreased the expression of anti-apoptotic protein Bcl-2 and enhanced the expression of apoptosis-related proteins like Bax and Cleaved-Caspase3. In addition, treatment with Mn resulted in elevated ROS levels and increased phosphorylation levels of JNK. Conversely, phosphorylation of nuclear transcription factors FOXO3a, which regulates expression of transcription factors including Bim and PUMA, was decreased. Depletion of ROS by N-acetyl-L-cysteine (NAC) and inhibition of the JNK pathway by SP600125 prevented Mn-induced JNK/FOXO3a pathway activation and, more importantly, the level of apoptosis was also significantly reduced. Confirmation of Mn-induced apoptosis in CTX cells through ROS generation and activation of the JNK/FOXO3a signaling pathway was the outcome of this study. These findings offer fresh insights into the neurotoxic mechanisms of Mn and therapeutic targets following Mn exposure.

16.
Ecotoxicol Environ Saf ; 249: 114337, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36508835

RESUMO

The extent to which neurodevelopment is affected by prenatal lead exposure has not been conclusive. In addition, studies on the effects of sex on these relationships are inconsistent. The aim of this study was to investigate the impact of cord blood lead on neurodevelopment in children within sex subgroups. A total of 275 mother-child pairs from the Shanghai mother-child cohort were included. Umbilical cord blood lead was measured using graphite furnace atomic absorption spectrophotometry. The Bayley Scales for Infant Development-III (BSID-III) was used to measure the neurodevelopment of infants at the age of 18 ± 1.5 months. The median and interquartile range of cord blood lead levels in the total participants, male, and female children were 44.0 (24.5) µg/L, 44.0 (24.3) µg/L, and 46.0 (24.0) µg/L, respectively. According to multiple linear regression, cord blood lead concentrations showed a negative association with fine motor scores in all models associated with female children (ß = -1.5; 95%confidence interval: -2.6, -0.4). However, prenatal lead levels were not associated with any of the BSID-III scores in male children. In addition, cord serum DHA was found positively related to fine motor scores in male children. Our findings suggest that prenatal lead exposure could lead to decreased motor function, although this phenomenon was only observed in female children. And DHA may be a protective factor against lead exposure in boys. Thus, further studies are needed to investigate the associations between prenatal lead exposure and neurobehavioral development, as well as the mechanism of sex differences.


Assuntos
Chumbo , Efeitos Tardios da Exposição Pré-Natal , Lactente , Gravidez , Humanos , Masculino , Feminino , Chumbo/toxicidade , Sangue Fetal , China , Relações Mãe-Filho
17.
Ecotoxicol Environ Saf ; 264: 115394, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37625333

RESUMO

Intrauterine exposure to heavy metals may adversely affect the developing fetus and health later in life, while certain trace elements may be protective. There is limited data on their dynamic fluctuation in circulating concentration of women from preconception to pregnancy and the degree of transplacental passage to fetus. Such information is critically needed for an optimal design of research studies and intervention strategies. In the present study, we profiled the longitudinal patterns and trajectories of metal(loid)s and trace elements from preconception to late pregnancy and in newborns. We measured whole blood metal(loid)s in women at preconception, 16, 24 and 32 weeks of gestation and in cord blood in 100 mother-newborn pairs. Our data showed that the mean concentrations of mercury (Hg), lead (Pb), rubidium (Rb), manganese (Mn), and iron (Fe) were lower during early-, mid-, and late-pregnancy than at preconception. Copper (Cu), and calcium (Ca) concentrations increased after pregnancy (Cu 798 versus 1353, 1488, and 1464 µg/L). Concentrations at preconception were correlated with those during pregnancy for all examined metal(loid)s. Maternal Hg, Pb, and Se concentrations at late-pregnancy were correlated with those in newborn cord blood in various degrees (correlation coefficients: Hg 0.66, Pb 0.29, Se 0.39). The estimated placental transfer ratio for toxic metal(loid)s ranging from 1.68 (Hg) to 0.18 (Cd). Two trajectory groups were identified for Hg, Pb, Cd, Se concentrations. Hg concentrations may be correlated with maternal education levels. The study is the first to present longitudinal circulating concentration trajectories of toxic metal(loid)s and trace elements from preconception to pregnancy stages. A high degree of transplacental passage was observed in toxic metals Pb and Hg which may pose hazards to the developing fetus.


Assuntos
Mercúrio , Metais Pesados , Oligoelementos , Feminino , Recém-Nascido , Gravidez , Humanos , Cádmio , Chumbo , Placenta , Metais Pesados/toxicidade , Intoxicação por Metais Pesados , Sangue Fetal
18.
Ecotoxicol Environ Saf ; 259: 115026, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37210997

RESUMO

Despite the ubiquity and prevalence of lead (Pb) in the environment and industry, the mechanism of lead-induced neurotoxicity in the brain remains unclear, let alone its prevention and treatment. In this study, we hypothesized that exogenous cholesterol supplementation acts as an effective remedy for lead-induced neurodevelopmental impairments caused by lead. Forty 21-day-old male rats were randomly divided into four groups and administered 0.1 % lead water and/or 2 % cholesterol-containing feed for 30 d. Ultimately, rats in the lead group lost weight, accompanied by spatial learning and memory impairments as verified by the Morris water maze test, in which the escape latency of rats was prolonged, and the number of crossings in the target platform and the residence time in the target quadrant were significantly diminished compared to the control group. Hematoxylin-Eosin (H&E) staining and Nissl staining illustrated that typical pathological morphology occurred in the brain tissue of the lead group, where the tissue structure was loose, the number of hippocampal neurons and granulosa cells decreased significantly and were arranged loosely, along with enlarged intercellular space, light matrix staining, and decline in Nissl bodies. In addition, inflammatory response and oxidative stress were significantly induced by lead. Immunofluorescence experiments showed apparent activation of astrocytes and microglia, followed by the enhancement of TNF-α and IL-ß levels. Moreover, the MDA content in the lead group was elevated dramatically, whereas the activities of SOD and GSH were significantly inhibited. As for the mechanism, western blot and qRT-PCR experiments were performed, where lead could significantly inhibit the BDNF-TrkB signaling pathway, lowering the protein expression of BDNF and TrkB. Cholesterol metabolism was also affected by lead exposure, in which cholesterol metabolism-related protein expression and gene transcription, including SREBP2, HMGCR, and LDLR, were downregulated. However, cholesterol supplementation efficiently detoxified the negative effects of lead-induced neurotoxicity, reversing the inflammatory response, oxidative stress, inactivation of the BDNF signaling pathway, and imbalance of cholesterol metabolism, thus improving the learning and memory ability of rats. In brief, our study demonstrated that cholesterol supplementation could ameliorate the deficiency of learning and memory induced by lead, which is closely associated with the initiation of the BDNF/TrkB signaling pathway and regulation of cholesterol metabolism.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Chumbo , Feminino , Ratos , Animais , Masculino , Ratos Sprague-Dawley , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Chumbo/metabolismo , Transdução de Sinais , Hipocampo/metabolismo , Suplementos Nutricionais , Aprendizagem em Labirinto
19.
Angew Chem Int Ed Engl ; 62(37): e202303888, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37186770

RESUMO

Rechargeable lithium batteries are one of the most appropriate energy storage systems in our electrified society, as virtually all portable electronic devices and electric vehicles today rely on the chemical energy stored in them. However, sub-zero Celsius operation, especially below -20 °C, remains a huge challenge for lithium batteries and greatly limits their application in extreme environments. Slow Li+ diffusion and charge transfer kinetics have been identified as two main origins of the poor performance of RLBs under low-temperature conditions, both strongly associated with the liquid electrolyte that governs bulk and interfacial ion transport. In this review, we first analyze the low-temperature kinetic behavior and failure mechanism of lithium batteries from an electrolyte standpoint. We next trace the history of low-temperature electrolytes in the past 40 years (1983-2022), followed by a comprehensive summary of the research progress as well as introducing the state-of-the-art characterization and computational methods for revealing their underlying mechanisms. Finally, we provide some perspectives on future research of low-temperature electrolytes with particular emphasis on mechanism analysis and practical application.

20.
Angew Chem Int Ed Engl ; 62(4): e202214828, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36383099

RESUMO

Extreme fast charging (XFC) of high-energy Li-ion batteries is a key enabler of electrified transportation. While previous studies mainly focused on improving Li ion mass transport in electrodes and electrolytes, the limitations of charge transfer across electrode-electrolyte interfaces remain underexplored. Herein we unravel how charge transfer kinetics dictates the fast rechargeability of Li-ion cells. Li ion transfer across the cathode-electrolyte interface is found to be rate-limiting during XFC, but the charge transfer energy barrier at both the cathode and anode have to be reduced simultaneously to prevent Li plating, which is achieved through electrolyte engineering. By unlocking charge transfer limitations, 184 Wh kg-1 pouch cells demonstrate stable XFC (10-min charge to 80 %) which is otherwise unachievable, and the lifetime of 245 Wh kg-1 21700 cells is quintupled during fast charging (25-min charge to 80 %).

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