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1.
Mol Cell ; 79(3): 521-534.e15, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32592681

RESUMO

Genome-wide mapping of chromatin interactions at high resolution remains experimentally and computationally challenging. Here we used a low-input "easy Hi-C" protocol to map the 3D genome architecture in human neurogenesis and brain tissues and also demonstrated that a rigorous Hi-C bias-correction pipeline (HiCorr) can significantly improve the sensitivity and robustness of Hi-C loop identification at sub-TAD level, especially the enhancer-promoter (E-P) interactions. We used HiCorr to compare the high-resolution maps of chromatin interactions from 10 tissue or cell types with a focus on neurogenesis and brain tissues. We found that dynamic chromatin loops are better hallmarks for cellular differentiation than compartment switching. HiCorr allowed direct observation of cell-type- and differentiation-specific E-P aggregates spanning large neighborhoods, suggesting a mechanism that stabilizes enhancer contacts during development. Interestingly, we concluded that Hi-C loop outperforms eQTL in explaining neurological GWAS results, revealing a unique value of high-resolution 3D genome maps in elucidating the disease etiology.


Assuntos
Cromatina/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Genoma Humano , Neurogênese/genética , Regiões Promotoras Genéticas , Adulto , Linhagem Celular , Cérebro/citologia , Cérebro/crescimento & desenvolvimento , Cérebro/metabolismo , Cromatina/ultraestrutura , Mapeamento Cromossômico , Feto , Histonas/genética , Histonas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas do Tecido Nervoso/classificação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurônios/citologia , Neurônios/metabolismo , Lobo Temporal/citologia , Lobo Temporal/crescimento & desenvolvimento , Lobo Temporal/metabolismo , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Nat Methods ; 20(6): 824-835, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37069271

RESUMO

BigNeuron is an open community bench-testing platform with the goal of setting open standards for accurate and fast automatic neuron tracing. We gathered a diverse set of image volumes across several species that is representative of the data obtained in many neuroscience laboratories interested in neuron tracing. Here, we report generated gold standard manual annotations for a subset of the available imaging datasets and quantified tracing quality for 35 automatic tracing algorithms. The goal of generating such a hand-curated diverse dataset is to advance the development of tracing algorithms and enable generalizable benchmarking. Together with image quality features, we pooled the data in an interactive web application that enables users and developers to perform principal component analysis, t-distributed stochastic neighbor embedding, correlation and clustering, visualization of imaging and tracing data, and benchmarking of automatic tracing algorithms in user-defined data subsets. The image quality metrics explain most of the variance in the data, followed by neuromorphological features related to neuron size. We observed that diverse algorithms can provide complementary information to obtain accurate results and developed a method to iteratively combine methods and generate consensus reconstructions. The consensus trees obtained provide estimates of the neuron structure ground truth that typically outperform single algorithms in noisy datasets. However, specific algorithms may outperform the consensus tree strategy in specific imaging conditions. Finally, to aid users in predicting the most accurate automatic tracing results without manual annotations for comparison, we used support vector machine regression to predict reconstruction quality given an image volume and a set of automatic tracings.


Assuntos
Benchmarking , Microscopia , Microscopia/métodos , Imageamento Tridimensional/métodos , Neurônios/fisiologia , Algoritmos
3.
Circ Res ; 134(7): 913-930, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38414132

RESUMO

BACKGROUND: Recently shown to regulate cardiac development, the secreted axon guidance molecule SLIT3 maintains its expression in the postnatal heart. Despite its known expression in the cardiovascular system after birth, SLIT3's relevance to cardiovascular function in the postnatal state remains unknown. As such, the objectives of this study were to determine the postnatal myocardial sources of SLIT3 and to evaluate its functional role in regulating the cardiac response to pressure overload stress. METHODS: We performed in vitro studies on cardiomyocytes and myocardial tissue samples from patients and performed in vivo investigation with SLIT3 and ROBO1 (roundabout homolog 1) mutant mice undergoing transverse aortic constriction to establish the role of SLIT3-ROBO1 in adverse cardiac remodeling. RESULTS: We first found that SLIT3 transcription was increased in myocardial tissue obtained from patients with congenital heart defects that caused ventricular pressure overload. Immunostaining of hearts from WT (wild-type) and reporter mice revealed that SLIT3 is secreted by cardiac stromal cells, namely fibroblasts and vascular mural cells, within the heart. Conditioned media from cardiac fibroblasts and vascular mural cells both stimulated cardiomyocyte hypertrophy in vitro, an effect that was partially inhibited by an anti-SLIT3 antibody. Also, the N-terminal, but not the C-terminal, fragment of SLIT3 and the forced overexpression of SLIT3 stimulated cardiomyocyte hypertrophy and the transcription of hypertrophy-related genes. We next determined that ROBO1 was the most highly expressed roundabout receptor in cardiomyocytes and that ROBO1 mediated SLIT3's hypertrophic effects in vitro. In vivo, Tcf21+ fibroblast and Tbx18+ vascular mural cell-specific knockout of SLIT3 in mice resulted in decreased left ventricular hypertrophy and cardiac fibrosis after transverse aortic constriction. Furthermore, α-MHC+ cardiomyocyte-specific deletion of ROBO1 also preserved left ventricular function and abrogated hypertrophy, but not fibrosis, after transverse aortic constriction. CONCLUSIONS: Collectively, these results indicate a novel role for the SLIT3-ROBO1-signaling axis in regulating postnatal cardiomyocyte hypertrophy induced by pressure overload.


Assuntos
Miócitos Cardíacos , Proteínas do Tecido Nervoso , Animais , Humanos , Camundongos , Cardiomegalia/genética , Cardiomegalia/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Hipertrofia Ventricular Esquerda/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Remodelação Ventricular
4.
Nature ; 582(7812): 370-374, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555490

RESUMO

The well known trade-off between hardness and toughness (resistance to fracture) makes simultaneous improvement of both properties challenging, especially in diamond. The hardness of diamond can be increased through nanostructuring strategies1,2, among which the formation of high-density nanoscale twins - crystalline regions related by symmetry - also toughens diamond2. In materials other than diamond, there are several other promising approaches to enhancing toughness in addition to nanotwinning3, such as bio-inspired laminated composite toughening4-7, transformation toughening8 and dual-phase toughening9, but there has been little research into such approaches in diamond. Here we report the structural characterization of a diamond composite hierarchically assembled with coherently interfaced diamond polytypes (different stacking sequences), interwoven nanotwins and interlocked nanograins. The architecture of the composite enhances toughness more than nanotwinning alone, without sacrificing hardness. Single-edge notched beam tests yield a toughness up to five times that of synthetic diamond10, even greater than that of magnesium alloys. When fracture occurs, a crack propagates through diamond nanotwins of the 3C (cubic) polytype along {111} planes, via a zigzag path. As the crack encounters regions of non-3C polytypes, its propagation is diffused into sinuous fractures, with local transformation into 3C diamond near the fracture surfaces. Both processes dissipate strain energy, thereby enhancing toughness. This work could prove useful in making superhard materials and engineering ceramics. By using structural architecture with synergetic effects of hardening and toughening, the trade-off between hardness and toughness may eventually be surmounted.

5.
Nucleic Acids Res ; 52(6): 2886-2903, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38142446

RESUMO

Adjusting intracellular metabolic pathways and adopting suitable live state such as biofilms, are crucial for bacteria to survive environmental changes. Although substantial progress has been made in understanding how the histone-like nucleoid-structuring (H-NS) protein modulates the expression of the genes involved in biofilm formation, the precise modification that the H-NS protein undergoes to alter its DNA binding activity is still largely uncharacterized. This study revealed that acetylation of H-NS at Lys19 inhibits biofilm development in Shewanella oneidensis MR-1 by downregulating the expression of glutamine synthetase, a critical enzyme in glutamine synthesis. We further found that nitrogen starvation, a likely condition in biofilm development, induces deacetylation of H-NS and the trimerization of nitrogen assimilation regulator GlnB. The acetylated H-NS strain exhibits significantly lower cellular glutamine concentration, emphasizing the requirement of H-NS deacetylation in Shewanella biofilm development. Moreover, we discovered in vivo that the activation of glutamine biosynthesis pathway and the concurrent suppression of the arginine synthesis pathway during both pellicle and attached biofilms development, further suggesting the importance of fine tune nitrogen assimilation by H-NS acetylation in Shewanella. In summary, posttranslational modification of H-NS endows Shewanella with the ability to respond to environmental needs by adjusting the intracellular metabolism pathways.


Assuntos
Histonas , Shewanella , Acetilação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Glutamina/genética , Histonas/metabolismo , Homeostase , Processamento de Proteína Pós-Traducional , Shewanella/genética , Shewanella/metabolismo
6.
Proc Natl Acad Sci U S A ; 120(32): e2222036120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37523563

RESUMO

Intracellular plant immune receptors, termed NLRs (Nucleotide-binding Leucine-rich repeat Receptors), confer effector-triggered immunity. Sensor NLRs are responsible for pathogen effector recognition. Helper NLRs function downstream of sensor NLRs to transduce signaling and induce cell death and immunity. Activation of sensor NLRs that contain TIR (Toll/interleukin-1receptor) domains generates small molecules that induce an association between a downstream heterodimer signalosome of EDS1 (EnhancedDisease Susceptibility 1)/SAG101 (Senescence-AssociatedGene 101) and the helper NLR of NRG1 (NRequired Gene 1). Autoactive NRG1s oligomerize and form calcium signaling channels largely localized at the plasma membrane (PM). The molecular mechanisms of helper NLR PM association and effector-induced NRG1 oligomerization are not well characterized. We demonstrate that helper NLRs require positively charged residues in their N-terminal domains for phospholipid binding and PM association before and after activation, despite oligomerization and conformational changes that accompany activation. We demonstrate that effector activation of a TIR-containing sensor NLR induces NRG1 oligomerization at the PM and that the cytoplasmic pool of EDS1/SAG101 is critical for cell death function. EDS1/SAG101 cannot be detected in the oligomerized NRG1 resistosome, suggesting that additional unknown triggers might be required to induce the dissociation of EDS1/SAG101 from the previously described NRG1/EDS1/SAG101 heterotrimer before subsequent NRG1 oligomerization. Alternatively, the conformational changes resulting from NRG1 oligomerization abrogate the interface for EDS1/SAG101 association. Our data provide observations regarding dynamic PM association during helper NLR activation and underpin an updated model for effector-induced NRG1 resistosome formation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas NLR/genética , Imunidade Vegetal/genética , Plantas/metabolismo , Receptores Imunológicos/metabolismo , Membrana Celular/metabolismo , Doenças das Plantas , Hidrolases de Éster Carboxílico/genética
7.
PLoS Pathog ; 19(6): e1011470, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37347782

RESUMO

The study of carrier state phages challenged the canonical lytic-lysogenic binary, and carrier state appears to be ubiquitous and ecologically important. However, the mechanisms of the carrier state are not well elucidated due to the limited phage models. Herein, we reported phage HQ103, similar to Escherichia coli phage P2. In contrast to the temperate P2 phage, the HQ103 phage does not insert its genome into the bacterial chromosome and displays a dual behavior depending on the temperature. At 37°C, HQ103 lyses the host and forms clear plaques due to the truncation of repressor CI and mutation of promoter Pc. In contrast, HQ103 maintains a carrier state lifestyle with Y. pestis at an environmental temperature (21°C). Mechanistically, we found that the host-encoded histone-like nucleoid-structuring protein H-NS, which is highly expressed at 21°C to silence the Cox promoter Pe and inhibits the phage lytic cycle. Subsequently, the HQ103 carrier state Y. pestis could grow and co-exist with the phage in the soil at 21°C for one month. Thus, this study reveals a novel carrier state lifestyle of phage HQ103 due to the H-NS mediated xenogeneic silencing and demonstrates that the carrier state lifestyle could promote long-term phage-host coexist in nature.


Assuntos
Bacteriófagos , Yersinia pestis , Bacteriófagos/genética , Solo , Portador Sadio , Temperatura , Lisogenia
8.
PLoS Genet ; 18(7): e1009977, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35788729

RESUMO

African descent populations have a lower Alzheimer disease risk from ApoE ε4 compared to other populations. Ancestry analysis showed that the difference in risk between African and European populations lies in the ancestral genomic background surrounding the ApoE locus (local ancestry). Identifying the mechanism(s) of this protection could lead to greater insight into the etiology of Alzheimer disease and more personalized therapeutic intervention. Our objective is to follow up the local ancestry finding and identify the genetic variants that drive this risk difference and result in a lower risk for developing Alzheimer disease in African ancestry populations. We performed association analyses using a logistic regression model with the ApoE ε4 allele as an interaction term and adjusted for genome-wide ancestry, age, and sex. Discovery analysis included imputed SNP data of 1,850 Alzheimer disease and 4,331 cognitively intact African American individuals. We performed replication analyses on 63 whole genome sequenced Alzheimer disease and 648 cognitively intact Ibadan individuals. Additionally, we reproduced results using whole-genome sequencing of 273 Alzheimer disease and 275 cognitively intact admixed Puerto Rican individuals. A further comparison was done with SNP imputation from an additional 8,463 Alzheimer disease and 11,365 cognitively intact non-Hispanic White individuals. We identified a significant interaction between the ApoE ε4 allele and the SNP rs10423769_A allele, (ß = -0.54,SE = 0.12,p-value = 7.50x10-6) in the discovery data set, and replicated this finding in Ibadan (ß = -1.32,SE = 0.52,p-value = 1.15x10-2) and Puerto Rican (ß = -1.27,SE = 0.64,p-value = 4.91x10-2) individuals. The non-Hispanic Whites analyses showed an interaction trending in the "protective" direction but failing to pass a 0.05 significance threshold (ß = -1.51,SE = 0.84,p-value = 7.26x10-2). The presence of the rs10423769_A allele reduces the odds ratio for Alzheimer disease risk from 7.2 for ApoE ε4/ε4 carriers lacking the A allele to 2.1 for ApoE ε4/ε4 carriers with at least one A allele. This locus is located approximately 2 mB upstream of the ApoE locus, in a large cluster of pregnancy specific beta-1 glycoproteins on chromosome 19 and lies within a long noncoding RNA, ENSG00000282943. This study identified a new African-ancestry specific locus that reduces the risk effect of ApoE ε4 for developing Alzheimer disease. The mechanism of the interaction with ApoEε4 is not known but suggests a novel mechanism for reducing the risk for ε4 carriers opening the possibility for potential ancestry-specific therapeutic intervention.


Assuntos
Doença de Alzheimer , Alelos , Doença de Alzheimer/genética , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Genótipo , Humanos , Nigéria , Fatores de Risco
9.
J Am Chem Soc ; 146(18): 12485-12495, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38651836

RESUMO

Understanding the mechanisms of C-H activation of alkanes is a very important research topic. The reactions of metal clusters with alkanes have been extensively studied to reveal the electronic features governing C-H activation, while the experimental cluster reactivity was qualitatively interpreted case by case in the literature. Herein, we prepared and mass-selected over 100 rhodium-based clusters (RhxVyOz- and RhxCoyOz-) to react with light alkanes, enabling the determination of reaction rate constants spanning six orders of magnitude. A satisfactory model being able to quantitatively describe the rate data in terms of multiple cluster electronic features (average electron occupancy of valence s orbitals, the minimum natural charge on the metal atom, cluster polarizability, and energy gap involved in the agostic interaction) has been constructed through a machine learning approach. This study demonstrates that the general mechanisms governing the very important process of C-H activation by diverse metal centers can be discovered by interpreting experimental data with artificial intelligence.

10.
BMC Med Res Methodol ; 24(1): 4, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38177983

RESUMO

BACKGROUND: Identification of difficult laryngoscopy is a frequent demand in cervical spondylosis clinical surgery. This work aims to develop a hybrid architecture for identifying difficult laryngoscopy based on new indexes. METHODS: Initially, two new indexes for identifying difficult laryngoscopy are proposed, and their efficacy for predicting difficult laryngoscopy is compared to that of two conventional indexes. Second, a hybrid adaptive architecture with convolutional layers, spatial extraction, and a vision transformer is proposed for predicting difficult laryngoscopy. The proposed adaptive hybrid architecture is then optimized by determining the optimal location for extracting spatial information. RESULTS: The test accuracy of four indexes using simple model is 0.8320. The test accuracy of optimized hybrid architecture using four indexes is 0.8482. CONCLUSION: The newly proposed two indexes, the angle between the lower margins of the second and sixth cervical spines and the vertical direction, are validated to be effective for recognizing difficult laryngoscopy. In addition, the optimized hybrid architecture employing four indexes demonstrates improved efficacy in detecting difficult laryngoscopy. TRIAL REGISTRATION: Ethics permission for this research was obtained from the Medical Scientific Research Ethics Committee of Peking University Third Hospital (IRB00006761-2015021) on 30 March 2015. A well-informed agreement has been received from all participants. Patients were enrolled in this research at the Chinese Clinical Trial Registry ( http://www.chictr.org.cn , identifier: ChiCTR-ROC-16008598) on 6 June 2016.


Assuntos
Laringoscopia , Espondilose , Humanos , Vértebras Cervicais , Hospitais Universitários , Espondilose/cirurgia
11.
BMC Public Health ; 24(1): 134, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195459

RESUMO

BACKGROUND: We investigated the synergistic effect of stress and habitual salt preference (SP) on blood pressure (BP) in the hospitalized Omicron-infected patients. METHODS: From 15,185 hospitalized Omicron-infected patients who reported having high BP or hypertension, we recruited 662 patients. All patients completed an electronic questionnaire on diet and stress, and were required to complete morning BP monitoring at least three times. RESULTS: The hypertensive group (n = 309) had higher habitual SP (P = 0.015) and COVID-19 related stress (P < 0.001), and had longer hospital stays (7.4 ± 1.5 days vs. 7.2 ± 0.5 days, P = 0.019) compared with controls (n = 353). After adjusting for a wide range of covariates including Omicron epidemic-related stress, habitual SP was found to increase both systolic (4.9 [95% confidence interval (CI), 2.3-7.4] mmHg, P < 0.001) and diastolic (2.1 [95%CI, 0.6-3.6] mmHg, P = 0.006) BP in hypertensive patients, and increase diastolic BP (2.0 [95%CI, 0.2-3.7] mmHg, P = 0.026) in the control group. 31 (8.8%) patients without a history of hypertension were discovered to have elevated BP during hospitalization, and stress was shown to be different in those patients (P < 0.001). In contrast, habitual SP was more common in hypertensive patients with uncontrolled BP, compared with patients with controlled BP (P = 0.002). CONCLUSIONS: Habitual SP and psychosocial stress were associated with higher BP in Omicron-infected patients both with and without hypertension. Nonpharmaceutical intervention including dietary guidance and psychiatric therapy are crucial for BP control during the long COVID-19 period.


Assuntos
Hipertensão , Síndrome de COVID-19 Pós-Aguda , Cloreto de Sódio na Dieta , Humanos , Pressão Sanguínea , Hipertensão/epidemiologia , Pacientes , Cloreto de Sódio na Dieta/efeitos adversos , Estresse Psicológico
12.
J Med Internet Res ; 26: e52646, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663006

RESUMO

BACKGROUND: Patients using web-based health care communities for e-consultation services have the option to choose their service providers from an extensive digital market. To stand out in this crowded field, doctors in web-based health care communities often engage in prosocial behaviors, such as proactive and reactive actions, to attract more users. However, the effect of these behaviors on the volume of e-consultations remains unclear and warrants further exploration. OBJECTIVE: This study investigates the impact of various prosocial behaviors on doctors' e-consultation volume in web-based health care communities and the moderating effects of doctors' digital and offline reputations. METHODS: A panel data set containing information on 2880 doctors over a 22-month period was obtained from one of the largest web-based health care communities in China. Data analysis was conducted using a 2-way fixed effects model with robust clustered SEs. A series of robustness checks were also performed, including alternative measurements of independent variables and estimation methods. RESULTS: Results indicated that both types of doctors' prosocial behaviors, namely, proactive and reactive actions, positively impacted their e-consultation volume. In terms of the moderating effects of external reputation, doctors' offline professional titles were found to negatively moderate the relationship between their proactive behaviors and their e-consultation volume. However, these titles did not significantly affect the relationship between doctors' reactive behaviors and their e-consultation volume (P=.45). Additionally, doctors' digital recommendations from patients negatively moderated both the relationship between doctors' proactive behaviors and e-consultation volume and the relationship between doctors' reactive behaviors and e-consultation volume. CONCLUSIONS: Drawing upon functional motives theory and social exchange theory, this study categorizes doctors' prosocial behaviors into proactive and reactive actions. It provides empirical evidence that prosocial behaviors can lead to an increase in e-consultation volume. This study also illuminates the moderating roles doctors' digital and offline reputations play in the relationships between prosocial behaviors and e-consultation volume.


Assuntos
Internet , Humanos , China , Feminino , Masculino , Médicos/psicologia , Médicos/estatística & dados numéricos , Comportamento Social , Adulto , Consulta Remota/estatística & dados numéricos , Consulta Remota/métodos
13.
Ecotoxicol Environ Saf ; 269: 115752, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039848

RESUMO

Fluoride could cause developmental neurotoxicity and significantly affect the intelligence quotient (IQ) of children. However, the systematic mechanism of neuronal damage caused by excessive fluoride administration in offspring is largely unknown. Here, we present a comprehensive integrative transcriptome and metabolome analysis to study the mechanism of developmental neurotoxicity caused by chronic fluoride exposure. Comparing the different doses of fluoride treatments in two generations revealed the exclusive signature of metabolism pathways and gene expression profiles. In particular, neuronal development and synaptic ion transport are significantly altered at the gene expression and metabolite accumulation levels for both generations, which could act as messengers and enhancers of fluoride-induced systemic neuronal injury. Choline and arachidonic acid metabolism, which highlighted in the integrative analysis, exhibited different regulatory patterns between the two generations, particularly for synaptic vesicle formation and inflammatory factor transport. It may suggest that choline and arachidonic acid metabolism play important roles in developmental neurotoxic responses for offspring mice. Our study provides comprehensive insights into the metabolomic and transcriptomic regulation of fluoride stress responses in the mechanistic explanation of fluoride-induced developmental neurotoxicity.


Assuntos
Fluoretos , Síndromes Neurotóxicas , Humanos , Criança , Camundongos , Animais , Fluoretos/toxicidade , Transcriptoma , Ácido Araquidônico , Metaboloma , Síndromes Neurotóxicas/genética , Colina , Encéfalo
14.
Mikrochim Acta ; 191(2): 90, 2024 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214747

RESUMO

A novel mosaic structure Silica@C/Co@ZIF-67 composite was synthesized by successfully embedding Co nanoparticles on the surface of silica spheres with the help of thermoplastic polyethyleneimine by carbon-reduction. The ZIF-67 half-shell layer structure was synthesized by the in-situ growth of ZIF-67 on the surface of silica spheres through the coordination of 2-methylimidazole with Co metal nodes. The composite was used as a magnetic solid-phase extraction adsorbent combined with high performance liquid chromatography-ultraviolet detector (HPLC-UV) for the extraction and determination of benzoylurea insecticides (BUs) in vegetables and tea. Based on the presence of π-π, hydrophobic and hydrogen bonding interactions between Silica@C/Co@ZIF-67 and BUs, the BUs were rapidly captured by the composites resulting in high adsorption performance. Under the optimal extraction parameters, the linear ranges were 0.3-200 µg L-1 for diflubenzuron, 0.6-200 µg L-1 for chlorbenzuron, and 1.0-200 µg L-1 for triflumuron, teflubenzuron, and flufenoxuron, with correlation coefficients (R2) greater than 0.9991. The limits of detection (LODs) of the method were 0.1-0.3 µg L-1, and the relative standard deviations (RSDs) were 1.2-3.0% for intra-day and 2.6-4.6% for inter-day. In the spiked recovery experiments of vegetables and tea, the recoveries of the five kinds of BUs ranged from 75.8 to 112.9%. In addition, after 10 repetitions using Silica@C/Co@ZIF-67, the recoveries of the five kinds of BUs were still as high as 78.4 to 83.9%.


Assuntos
Diflubenzuron , Inseticidas , Inseticidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Chá/química , Dióxido de Silício
15.
Int J Phytoremediation ; 26(3): 339-348, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37553855

RESUMO

Cadmium (Cd) pollution is a huge threat to ecosystem health. In the manuscript, pot experiments were conducted to investigate the changes in plant biomass and antioxidant indicators under different cadmium pollution levels (0, 25, 50, and 100 mg/kg) of inoculation of plant growth-promoting bacteria ZG7 on sugar beet. The results showed that the accumulation of excess Cd in sugar beet exhibited different symptoms, including reduced biomass (p < 0.05). Compared with the group treated with uninoculated strain ZG7, inoculation of strain ZG7 significantly reduced the toxicity of sugar beet to Cd and enhanced its antioxidant capacity, with no significant differences in root biomass and increases in leaf biomass of 15.71, 5.84, and 74.12 under different Cd concentration treatments (25, 50, and 100 mg/kg), respectively. The root enrichment of Cd was reduced by 49.13, 47.26, and 21.50%, respectively (p < 0.05). The leaf fraction was reduced by 59.35, 29.86, and 30.99%, respectively (p < 0.05). In addition, the enzymatic activities of sucrase, urease, catalase, and neutral phosphatase were significantly enhanced in the soil (p < 0.05). This study helps us to further investigate the mechanism of cadmium toxicity reduction by inoculated microorganisms and provides a theoretical reference for growing plants in cadmium-contaminated agricultural fields.


The combination of microorganisms and phytoremediation is becoming a popular research topic. The selection of suitable plant growth promoting bacteria can not only promote the growth and development of plants and enhance their cadmium resistance, but also improve the soil quality. And the results of this study will be important for growing edible plants and improving soils in cadmium-contaminated areas.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/toxicidade , Antioxidantes , Ecossistema , Biodegradação Ambiental , Solo , Bactérias , Açúcares , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Raízes de Plantas/química
16.
Angew Chem Int Ed Engl ; 63(18): e202401050, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38444397

RESUMO

Geminal bis(boronates) are versatile synthetic building blocks in organic chemistry. The fact that they predominantly serve as nucleophiles in the previous reports, however, has restrained their synthetic potential. Herein we disclose the ambiphilic reactivity of α-halogenated geminal bis(boronates), of which the first catalytic utilization was accomplished by merging a formal Heck cross-coupling with a highly diastereoselective allylboration of aldehydes or imines, providing a new avenue for rapid assembly of polyfunctionalized boron-containing compounds. We demonstrated that this cascade reaction is highly efficient and compatible with various functional groups, and a wide range of heterocycles. In contrast to a classical Pd(0/II) scenario, mechanistic experiments and DFT calculations have provided strong evidence for a catalytic cycle involving Pd(I)/diboryl carbon radical intermediates.

17.
Reprod Biomed Online ; 47(5): 103304, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37757611

RESUMO

RESEARCH QUESTION: Do sphingosine 1-phosphate (S1P) modulators have therapeutic effects on endometriosis in mice and, if they do, which receptor is responsible for these effects? DESIGN: A surgically induced endometriosis mouse model was established. In the pilot experiment, lesions were harvested to assess fibrosis and inflammation and determine the optimal concentration of a broad-spectrum S1P modulator, FTY720. Subsequently, FTY720 was compared with a selective S1P receptor 1 modulator, SEW2871 to evaluate their effects on endometriotic lesion growth, fibrosis, inflammation and immune cell infiltration. RESULTS: The results demonstrated that both FTY720 and SEW2871, two S1P receptor modulators, effectively inhibited the growth and fibrosis of endometriotic lesions. SEW2871 inhibited inflammation-related cytokine expression, including PTGS-2, IL-1ß, TNF-α and TGF-ß1, more effectively compared with FTY720. Lymphopaenia was mainly caused by FTY720, whereas SEW2871 had a lesser effect. Both FTY720 and SEW2871 significantly reduced CD45+ cells (P = 0.002 and P = 0.032, respectively) and F4/80+ cells (P < 0.001 and P = 0.004, respectively) infiltration into the lesions, with FTY720 exerting a strong regulatory effect on CD4+ T cells. CONCLUSIONS: This study suggests that S1P receptor 1 could be investigated as a potential novel therapeutic target for endometriosis in the future.


Assuntos
Endometriose , Cloridrato de Fingolimode , Humanos , Feminino , Camundongos , Animais , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Receptores de Esfingosina-1-Fosfato , Endometriose/tratamento farmacológico , Esfingosina/farmacologia , Esfingosina/metabolismo , Esfingosina/uso terapêutico , Inflamação , Fibrose , Lisofosfolipídeos/metabolismo , Lisofosfolipídeos/farmacologia
18.
Fish Shellfish Immunol ; 137: 108750, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37084855

RESUMO

An ecdysteroid-regulated 16-kDa protein homolog (named Pc-E16), encoding 150 amino acid residues with a conserved MD-2-related lipid-recognition domain, was first identified in Procambarus clarkii. Phylogenetic analyses indicated similarity between Pc-E16 and 16-kDa proteins from Aplysia californica and insects. Recombinant Pc-E16 protein was successfully expressed in BL21 (DE3) Escherichia coli cells, and polyclonal antibodies against purified Pc-E16 proteins were prepared. In comparison with other tissues, Pc-E16 was highly expressed in the intestine; real-time PCR and Western blotting results indicated that Pc-E16 expression was significantly induced by lipopolysaccharides in hepatopancreas and hemocytes. Pc-E16-mediated signaling pathways were investigated by digital gene expression analysis following RNA interference targeting Pc-E16. A total of 6103 differentially expressed genes (DEGs) were identified, of which 3318 were up- and 2785 were downregulated. Many DEGs were involved in binding and catalytic activity. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that DEGs were clustered into 225 pathways, and 15 significantly enriched pathways were identified at the immune system level. In addition, the expression level of Pc-E16 in hemocytes and hepatopancreas was obviously downregulated at 48 h after dsRNA injection, and Pc-E16-RNAi treatment affected the expression levels of immune-related genes. Altogether, our results suggest that Pc-E16 is involved in the innate immune response of P. clarkii.


Assuntos
Astacoidea , Ecdisteroides , Animais , Ecdisteroides/metabolismo , Filogenia , Perfilação da Expressão Gênica , Imunidade Inata/genética , Proteínas Recombinantes/genética , Hepatopâncreas/metabolismo , Proteínas de Artrópodes
19.
Bioorg Med Chem ; 90: 117374, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37354726

RESUMO

The autoglobulin gene is the main enzyme for circulating LPA production and has lysophosphatidylcholine D activity, which catalyzes the production of lysophosphatidic acid and choline with lysophosphatidylcholine as substrate. A growing body of experimental evidence suggests that autoglobulin is involved in the pathogenesis of a variety of diseases. This review summarizes the different structural ATX inhibitors classified according to their binding mode to the ATX triple orientation site, and summarizes the conformational relationships and molecular docking of each type with ATX structure, hoping to contribute to the development of novel ATX inhibitors.


Assuntos
Lisofosfatidilcolinas , Diester Fosfórico Hidrolases , Diester Fosfórico Hidrolases/metabolismo , Lisofosfatidilcolinas/metabolismo , Simulação de Acoplamento Molecular , Lisofosfolipídeos/metabolismo
20.
Oral Dis ; 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36951790

RESUMO

OBJECTIVES: We aimed to investigate bone metastasis induced by Notch signalling pathway dysregulation and to demonstrate that SPARC is a potential therapeutic target in adenoid cystic carcinoma (AdCC) with Notch dysregulation. MATERIALS AND METHODS: This retrospective study enrolled 144 AdCC patients. RNA-sequencing and enrichment analyses were performed using 32 AdCC samples. Osteonectin/SPARC and the Notch activation indicator Notch intracellular domain (NICD) were detected using immunohistochemistry. Cell proliferation and migration assays were conducted using stably NICD over-expressing cells. The effect of SPARC on osteoclast differentiation in NICD cells was investigated using western blotting, quantitative reverse transcription PCR, tartrate-resistant acid phosphatase staining and resorption assays. RESULTS: RNA-sequencing analysis showed that genes down-regulated in Notch-mutant AdCCs, such as SPARC, were enriched in ossification and osteoblast differentiation. Most (75/110, 68.2%) Notch1-wild-type AdCCs showed SPARC over-expression, whereas 30 out of 34 (88.2%) Notch1-mutant tumours showed low SPARC expression. SPARC over-expression was then found negatively to be correlated with NICD expression in 144 AdCCs. NICD over-expression promoted cell growth, migration and osteoclast differentiation, which could be partly reversed by exogenous SPARC. CONCLUSIONS: Notch activation in AdCC contributes to bone metastasis through SPARC inhibition. The study results suggest that SPARC may represent a prognostic biomarker and potential therapeutic target.

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