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1.
Anal Chem ; 96(17): 6540-6549, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38619937

RESUMO

Composite materials built in part from living organisms have the potential to exhibit useful autonomous, adaptive, and self-healing behavior. The physicochemical, biological, and mechanical properties of such materials can be engineered through the genetic manipulation of their living components. Successful development of living materials will require not only new methods for design and preparation but also new analytical tools that are capable of real-time noninvasive mapping of chemical compositions. Here, we establish a strategy based on stimulated Raman scattering microscopy to monitor phosphatase-catalyzed mineralization of engineered bacterial films in situ. Real-time label-free imaging elucidates the mineralization process, quantifies both the organic and inorganic components of the material as functions of time, and reveals spatial heterogeneity at multiple scales. In addition, we correlate the mechanical performance of films with the extent of mineralization. This work introduces a promising strategy for quantitatively analyzing living materials, which should contribute to the accelerated development of such materials in the future.


Assuntos
Microscopia Óptica não Linear , Microscopia Óptica não Linear/métodos , Análise Espectral Raman/métodos , Fatores de Tempo , Monoéster Fosfórico Hidrolases/metabolismo
2.
Molecules ; 29(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38893484

RESUMO

To better assess the practical value and avoid potential risks of the traditionally medicinal and edible basidiomycete Schizophyllum commune, which may arise from undescribed metabolites, a combination of elicitors was introduced for the first time to discover products from cryptic and low-expressed gene clusters under laboratory cultivation. Treating S. commune NJFU21 with the combination of five elicitors led to the upregulated production of a class of unusual linear diterpene-derived variants, including eleven new ones (1-11), along with three known ones (12-14). The structures and stereochemistry were determined by 1D and 2D NMR, HRESIMS, ECD, OR and VCD calculations. Notably, the elongation terminus of all the diterpenes was decorated by an unusual butenedioic acid moiety. Compound 1 was a rare monocyclic diterpene, while 2-6 possessed a tetrahydrofuran moiety. The truncated metabolites 4, 5 and 13 belong to the trinorditerpenes. All the diterpenes displayed approximately 70% scavenging of hydroxyl radicals at 50 µM and null cytotoxic activity at 10 µM. In addition, compound 1 exhibited potent antifungal activity against the plant pathogenic fungi Colletotrichum camelliae, with MIC values of 8 µg/mL. Our findings indicated that this class of diterpenes could provide valuable protectants for cosmetic ingredients and the lead compounds for agricultural fungicide development.


Assuntos
Diterpenos , Schizophyllum , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/metabolismo , Schizophyllum/metabolismo , Schizophyllum/genética , Estrutura Molecular , Regulação para Cima/efeitos dos fármacos , Humanos
3.
Environ Sci Technol ; 57(31): 11634-11642, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37498082

RESUMO

As the concentration of microplastics/microspheres (MPs) in coastal and estuarine regions increases, the likelihood of disease outbreaks and epidemics also rises. Our study investigated the impact of polyvinyl chloride MPs (PVC-MPs) on white spot syndrome virus (WSSV) infection in shrimp. The results revealed that PVC-MPs obviously increased WSSV replication in vivo, leading to a high mortality rate among the larvae and facilitating the horizontal transmission of WSSV. Furthermore, the data of WSSV loads detected together with qPCR, agarose gel electrophoresis, and flow cytometry approaches indicated that PVC-MPs could interact with the virus to prolong survival and maintain the virulence of WSSV at different temperatures and pH values. In terms of host resistance, metabolomics and transcriptomics analysis demonstrated that exposure to PVC-MPs upregulated metabolic concentrations and gene expressions associated with phospholipid metabolism that were associated with innate immunity responses. Particularly, PVC-MPs stimulated the synthesis of phosphatidylcholine (PC) and induced lipid peroxidation. The inhibition of PC on Stimulator of Interferon Genes (STING) translocation from the endoplasmic reticulum to the Golgi apparatus reduces expression of the innate immunity genes (IFN-like genes Vago4 and Vago5) regulated by STING signaling pathways, resulting in a significant decrease in the shrimp's resistance to WSSV infection. Notably, a recovery operation in which the exposed larvae were transferred to a MPs-free aquatic environment led to decreased WSSV infectivity over time, indicating the restoration of antiviral properties in shrimp. Overall, these findings highlight that MPs promote shrimp susceptibility to WSSV in two aspects: host immune defense and viral virulence.


Assuntos
Penaeidae , Vírus da Síndrome da Mancha Branca 1 , Animais , Microplásticos , Plásticos , Vírus da Síndrome da Mancha Branca 1/genética , Virulência , Imunidade Inata/genética , Penaeidae/genética
4.
Opt Express ; 30(25): 45792-45806, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522976

RESUMO

The quantitative measurement of plasma soft x-ray spectra is an important diagnostic problem in indirect-drive laser inertial confinement fusion (ICF). We designed, built, and tested a compact multichannel soft x-ray spectrometer with both spatial and temporal resolution capabilities for the detection of the spatiotemporal distribution of soft x-ray spectra. The spectrometer occupies a small solid angle, and the close measurement angle used for each channel enables the measurement of the angular distribution of emitting soft x-rays in ICF experiments. The spectrometer comprises pinhole, filter, and multilayer flat mirror arrays, and an x-ray streak camera. Its energy range is 0.1 - 3 keV. The dispersive elements of the spectrometer were calibrated at the Beijing Synchrotron Radiation Facility. The accuracy of the calibration was ≤ 5%, and the combined energy resolution (E/ΔE) of the calibrated dispersive elements of each channel was higher than 10. Finally, the instrument was tested at the Shenguang-III Laser Facility. The measurement results of x-ray radiation flux are agreed well with the experimental results of the M-band flat-response x-ray diode, demonstrating the feasibility of the proposed spectrometer configuration.

5.
Opt Express ; 27(6): 8348-8360, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-31052654

RESUMO

The development of a polar-view Kirkpatrick-Baez microscope, fielded in the upper polar zone of the Shenguang-III laser fusion facility, is presented. With this microscope, the resolving power of polar-direction X-ray imaging diagnostics is improved, to the 3 ~5 µm scale. The microscope is designed for implosion asymmetry studies, with response energy points at 1.2 keV, 3.5 keV, and 8 keV. A biperiodic multilayer scheme is adopted to accommodate multiple implosion stages. We present the overall optical system design, target aiming scheme, characteristic composite imaging diagnostic experiments and initial results. The inertial-driven quasi-one-dimensional spherical implosions were observed from orthogonal directions with a convergence ratio of ~14.4. Fine features of the stagnating hot spot core are also resolved.

6.
Fish Shellfish Immunol ; 84: 1170-1179, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30366089

RESUMO

Stress response has negative effect on fish in aquaculture and research, which can be alleviated with anesthetic. To determine the optimal anesthetic, we investigated the physiological response of crucian carp (Carassius auratus) treated with three different anti-stress treatments: MS-222, eugenol and percussive stunning. Stress responses were evaluated by analyzing serum cortisol level and gene expression in blood. We determined the optimal concentrations of MS-222 (100 mg L-1) and eugenol (20 mg L-1) by dose selection. We found that the control group had significantly higher cortisol levels (172.78 ±â€¯19.95 ng mL-1) compared to the MS-222 treated group (46.85 ±â€¯3.22 ng mL-1), the eugenol treated group (72.78 ±â€¯9.07 ng mL-1), and the stunning treatment group (82.78 ±â€¯8.16 ng mL-1). Transcriptome analysis revealed 1572 differentially expressed genes (DEGs), including 155 DEGs related to the stress response, mainly involved in oxidative-stress response, heat shock proteins, and cold shock domain-containing protein. The heat shock protein genes were the primary DEGs in response to stress. RT-qPCR analysis confirmed differential expression of Hsps. We analyzed the function of the DEGs, which were enriched in genes involved in cellular response to stress and antigen processing and presentation. Combining the results from biochemical, transcriptome, and gene expression analysis, our data suggest that eugenol is more effective than MS-222 and percussive stunning in alleviating stress in crucian carp.


Assuntos
Aminobenzoatos/farmacologia , Anestesia/veterinária , Anestésicos/farmacologia , Carpas/fisiologia , Eugenol/farmacologia , Hidrocortisona/sangue , Anestesia/métodos , Animais , Carpas/genética , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica/veterinária , Carpa Dourada/genética , Carpa Dourada/fisiologia , Longevidade/efeitos dos fármacos , Estresse Fisiológico
7.
Mol Genet Genomics ; 293(3): 649-655, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29285564

RESUMO

The polymorphisms of cytokine genes has been reported to modulate the individual's susceptibility to environmental stimuli in COPD development. C-X-C motif chemokine 10 (CXCL10) mediates recruitment inflammatory cells such as monocytes. Therefore, it may play a key role in COPD. Here, a case-control study was conducted to evaluate the association between CXCL10 tag-SNPs and COPD risk. Four tag-SNPs including rs4256246, rs4508917, rs56061981, and rs56316945 were identified based on the linkage disequilibrium (LD) analysis in 30 healthy controls. The associations between these four tag-SNPs and COPD risk were further evaluated in 480 COPD cases and 488 controls. We found that the "T" allele of rs56061981 was significantly associated with reducing risk of COPD, while "G" allele of rs56316945 was significantly associated with increasing risk of COPD. SNP rs56316945 was significantly associated with increasing risk of COPD under different models except recessive model after adjusting the sex, age, pack year, and biomass. SNP rs56061981 was significantly associated with decreasing COPD risk under different models except recessive model after adjusting the sex, age, pack year, and biomass. Stratified analysis of smoking status and biomass with SNPs supported rs56061981 may interact with biomass and smoking thus modulate COPD susceptibility and rs56216945 was apparently associated with the severity of pulmonary function of COPD patients. This study suggests that rs56061981 and rs56216945 in CXCL10 gene promoter contribute COPD susceptibility.


Assuntos
Quimiocina CXCL10/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , Idoso , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas
8.
Exp Physiol ; 103(11): 1532-1542, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30070749

RESUMO

NEW FINDINGS: What is the central question of this study? In this study, by using motor vehicle exhaust (MVE) exposure with or without lipopolysaccharide (LPS) instillation, we established, evaluated and compared MVE, LPS and MVE+LPS treatment-induced chronic obstructive pulmonary disease (COPD) models in mice. What is the main finding and its importance? Our study demonstrated that the combination of chronic exposure to MVE with early LPS instillation can establish a mouse model with some features of COPD, which will allow researchers to investigate the underlying molecular mechanisms linking air pollution and COPD pathogenesis. ABSTRACT: Although it is well established that motor vehicle exhaust (MVE) has a close association with the occurrence and exacerbation of chronic obstructive pulmonary disease (COPD), very little is known about the combined effects of MVE and intermittent or chronic subclinical inflammation on COPD pathogenesis. Therefore, given the crucial role of inflammation in the development of COPD, we wanted to establish an animal model of COPD using both MVE exposure and airway inflammation, which could mimic the clinical pathological changes observed in COPD patients and greatly benefit the study of the molecular mechanisms of COPD. In the present study, we report that mice undergoing chronic exposure to MVE and intratracheal instillation of lipopolysaccharide (LPS) successfully established COPD, as characterized by persistent air flow limitation, airway inflammation, inflammatory cytokine production, emphysema and small airway remodelling. Moreover, the mice showed significant changes in ventricular and vascular pathology, including an increase in right ventricular pressure, right ventricular hypertrophy and remodelling of pulmonary arterial walls. We have thus established a new mouse COPD model by combining chronic MVE exposure with early intratracheal instillation of LPS, which will allow us to study the relationship between air pollution and the development of COPD and to investigate the underlying molecular mechanisms.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Lipopolissacarídeos/efeitos adversos , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Animais , Modelos Animais de Doenças , Camundongos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia
9.
J Am Chem Soc ; 138(47): 15307-15310, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27933926

RESUMO

In spite of widespread interest in rotaxane-based molecular machines and materials, rotaxanes have not been attached covalently to proteins. We describe the near-quantitative aqueous synthesis of [2]rotaxanes based on neutral and charged aqueous hosts-cucurbit[7]uril (CB7) and cyclobis(paraquat-p-phenylene) (CBPQT4+), respectively-using the thiol-ene addition of cysteine and maleimide as a stoppering protocol. After verifying the high efficiency of the reaction using glutathione (GSH) as an oligopeptide stopper, we have employed cytochrome C (CytC) as a protein stopper to produce the first well-characterized protein-rotaxane bioconjugates. We anticipate that this methodology will enable the preparation of novel materials that combine the unique properties of proteins and mechanical bonds.


Assuntos
Citocromos c/química , Glutationa/química , Oligopeptídeos/química , Rotaxanos/síntese química , Água/química , Citocromos c/metabolismo , Estrutura Molecular , Oligopeptídeos/metabolismo , Rotaxanos/química
10.
Bioorg Med Chem Lett ; 26(22): 5497-5500, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27765509

RESUMO

Estrogen biosynthesis is pivotal to many physiological processes of human. Aberrant estrogen level is closely related to a variety of diseases, including breast cancer and osteoporosis. Previously we found that 2-phenylbenzo[b]furan glycosides could promote estrogen biosynthesis. To find high active 2-phenylbenzo[b]furans, fifty-four 2-phenylbenzo[b]furans were prepared via four strategies according to corresponding substrate scopes. Biological evaluation in HEK293A cells showed that some compounds exhibited promotive activity on estrogen biosynthesis. 2-(4-Chlorophenyl)-7-methoxybenzo[b]furan possessed the highest activity with EC50 value of 14.68µM. Furthermore, these compounds did not affect aromatase expression in HEK292A cells, indicating that these 2-phenylbenzo[b]furans might enhance estrogen biosynthesis via directly allosteric regulation of aromatase or indirectly via posttranslational modification.


Assuntos
Derivados de Benzeno/química , Derivados de Benzeno/farmacologia , Estrogênios/agonistas , Estrogênios/metabolismo , Furanos/química , Furanos/farmacologia , Aromatase/metabolismo , Derivados de Benzeno/síntese química , Vias Biossintéticas/efeitos dos fármacos , Furanos/síntese química , Células HEK293 , Humanos
11.
J Asian Nat Prod Res ; 18(7): 711-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26982651

RESUMO

One new ursane-type triterpenoid (1), named granditriol, along with 14 known compounds (2-15), was isolated from the organic extracts of Schisandra grandiflora stems. The structure of the new compound was elucidated by extensive spectroscopic methods as 28-norursa-12,17,19,21-tetraen-2α,3α,23-triol. These isolates were evaluated for anti-phytopathogenic fungi activity and cytotoxicity against human cancer cell line (HepG2). Asiatic acid (8) and 2α,3α,19α-trihydroxyurs-12-en-28-oic acid (9) inhibited the growth of two plant pathogens, Alternaria alternata and Alternaria solani. In addition, compounds 12, 15, and 11 displayed notable anti-proliferative activity against HepG2 cells. Compound 1 is the first report of 28-nortriterpenoid from the Schisandraceae family. All these were obtained from this plant for the first time.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Schisandra/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Estrutura Molecular , Caules de Planta/química , Triterpenos/química
12.
J Fungi (Basel) ; 10(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38786720

RESUMO

The fermentation of a soil-derived fungus Acremonium sp. led to the isolation of thirteen ascochlorin congeners through integrated genomic and Global Natural Product Social (GNPS) molecular networking. Among the isolated compounds, we identified two unusual bicyclic types, acremochlorins O (1) and P (2), as well as two linear types, acremochlorin Q (3) and R (4). Compounds 1 and 2 contain an unusual benzopyran moiety and are diastereoisomers of each other, the first reported for the ascochlorins. Additionally, we elucidated the structure of 5, a 4-chloro-5-methylbenzene-1,3-diol with a linear farnesyl side chain, and confirmed the presence of eight known ascochlorin analogs (6-13). The structures were determined by the detailed interpretation of 1D and 2D NMR spectroscopy, MS, and ECD calculations. Compounds 3 and 9 showed potent antibacterial activity against Staphylococcus aureus and Bacillus cereus, with MIC values ranging from 2 to 16 µg/mL.

13.
FEBS J ; 290(16): 4092-4106, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37059697

RESUMO

Neuronal excitability is a critical feature of central nervous system development, playing a fundamental role in the functional maturation of brain regions, including the hippocampus, cerebellum, auditory and visual systems. The present study aimed to determine the mechanism by which hypoxia causes brain dysfunction through perturbation of neuronal excitability in a hypoxic neonatal mouse model. Functional brain development was assessed in humans using the Gesell Development Diagnosis Scale. In mice, gene transcription was evaluated via mRNA sequencing and quantitative PCR; furthermore, patch clamp recordings assessed potassium currents. Clinical observations revealed disrupted functional brain development in 6- and 18-month-old hypoxic neonates, and those born with normal hearing screening unexpectedly exhibited impaired central auditory function at 3 months. In model mice, CA1 pyramidal neurons exhibited reduced spontaneous activity, largely induced by excitatory synaptic input suppression, despite the elevated membrane excitability of hypoxic neurons compared to that of control neurons. In hypoxic neurons, Kcnd3 gene transcription was upregulated, confirming upregulated hippocampal Kv 4.3 expression. A-type potassium currents were enhanced, and Kv 4.3 participated in blocking excitatory presynaptic inputs. Elevated Kv 4.3 activity in pyramidal neurons under hypoxic conditions inhibited excitatory presynaptic inputs and further decreased neuronal excitability, disrupting functional brain development in hypoxic neonates.


Assuntos
Neurônios , Canais de Potássio , Humanos , Camundongos , Animais , Lactente , Animais Recém-Nascidos , Regulação para Cima , Neurônios/fisiologia , Hipocampo/fisiologia , Hipóxia/genética
14.
STAR Protoc ; 4(3): 102550, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37660297

RESUMO

Quantitative assessment of endogenously synthesized and released bilirubin from brain tissue remains a challenge. Here, we present a sensitive and reproducible experimental paradigm to quantify, in real time, unconjugated bilirubin (UCB) from isolated murine brain tissue during oxygen-glucose deprivation (OGD). We describe steps for perfusion, brain dissection, brain slice preparation and incubation, glucose depletion, and OGD processing. We then detail procedures for standard calibration plotting and sample UCB measurement. For complete details on the use and execution of this protocol, please refer to Liu et al.1.


Assuntos
Glucose , Oxigênio , Camundongos , Animais , Bilirrubina , Encéfalo , Cabeça
15.
Neuron ; 111(10): 1609-1625.e6, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-36921602

RESUMO

Stroke prognosis is negatively associated with an elevation of serum bilirubin, but how bilirubin worsens outcomes remains mysterious. We report that post-, but not pre-, stroke bilirubin levels among inpatients scale with infarct volume. In mouse models, bilirubin increases neuronal excitability and ischemic infarct, whereas ischemic insults induce the release of endogenous bilirubin, all of which are attenuated by knockout of the TRPM2 channel or its antagonist A23. Independent of canonical TRPM2 intracellular agonists, bilirubin and its metabolic derivatives gate the channel opening, whereas A23 antagonizes it by binding to the same cavity. Knocking in a loss of binding point mutation for bilirubin, TRPM2-D1066A, effectively antagonizes ischemic neurotoxicity in mice. These findings suggest a vicious cycle of stroke injury in which initial ischemic insults trigger the release of endogenous bilirubin from injured cells, which potentially acts as a volume neurotransmitter to activate TRPM2 channels, aggravating Ca2+-dependent brain injury.


Assuntos
Acidente Vascular Cerebral , Canais de Cátion TRPM , Animais , Camundongos , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo , Bilirrubina/metabolismo , Camundongos Knockout , Encéfalo/metabolismo , Infarto , Cálcio/metabolismo
16.
Clin Invest Med ; 35(5): E294, 2012 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-23043710

RESUMO

PURPOSE: Recent reports have linked various autoimmune diseases to defective Fas-mediated apoptosis or Fas expression. Here we aimed to determine whether Fas-mediated apoptosis is involved in the pathogenesis of myasthenia gravis (MG). METHODS: The expression of Fas antigen in peripheral T cell subsets from 17 Chinese patients with MG and 13 healthy individuals was determined by flow cytometry, and its associations with clinical classification, thymus pathology, the concomitance with hyperthyroidism (HT) and corticosteroid treatment were investigated. RESULTS: Compared with normal controls, a significantly up-regulated expression of Fas antigen was observed in the peripheral CD4+, CD4+CD8- and CD4-CD8- T cell subsets from patients with MG. Fas expression in CD4-CD8+ T cells of MG patients with normal thymus was significantly higher than that of patients with thymoma. Fas expressions in CD4+CD8+ T cells in MG patients with HT was significantly higher than controls and the ones without HT. Enhanced Fas expressions was found in CD4-CD8+ and CD4-CD8- T cells of MG patients with corticosteroid treatment, but no significant difference of Fas expression in peripheral T cells between patients with ocular MG (OMG) and general MG (GMG) was observed. CONCLUSION: Fas antigen may play a role in the pathogenesis of MG. It may be involved in the mechanisms of corticosteroid treatment, and with the occurrence of HT. OMG may represent a systemic disease, similar to that of GMG.


Assuntos
Miastenia Gravis/imunologia , Subpopulações de Linfócitos T/imunologia , Receptor fas/metabolismo , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Doença de Graves/complicações , Doença de Graves/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/complicações , Miastenia Gravis/etiologia , Miastenia Gravis/patologia , Subpopulações de Linfócitos T/metabolismo , Timo/patologia , Regulação para Cima
17.
Materials (Basel) ; 15(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36295388

RESUMO

Accurately predicting resistance spot welding (RSW) quality is essential for the manufacturing process. In this study, the RSW process signals of 2219/5A06 aluminum alloy under two assembly conditions (including gap and spacing) were analyzed, and then artificial intelligence modeling was carried out. To improve the performance and efficiency of RSW quality evaluation, this study proposed a multi-signal fusion method that was performed by combining principal component analysis and a correlation analysis. A backpropagation neural network (BPNN) model was optimized using the sine-chaotic-map-improved sparrow search algorithm (SSA), and the input and output of the model were the variables after multi-signal fusion and the button diameter, respectively. Compared with the standard BPNN model, the Sine-SSA-BP model reduced the MAE by 42.33%, MSE by 51.84%, and RMSE by 31.45%. Its R2 coefficient reached 0.6482, which is much higher than that of BP (0.2464). According to various indicators (MAE, MSE, RMSE, and R2), the evaluation performance of the Sine-SSA-BP model was better than that of the standard BPNN model. Compared with other models (BP, GA-BP, PSO-BP, SSA-BP, and Sine-PSO-BP), the evaluation performance of the Sine-SSA-BP model was best, which can successfully predict abnormal spot welds.

18.
Comput Math Methods Med ; 2022: 4212180, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36060663

RESUMO

Background: Neuronal apoptosis, which is the primary pathological transform of cerebral injury following ischemic stroke (IS), is considered to be induced by endoplasmic reticulum stress (ERS) by numerous reports. However, ERS biomarkers in IS have not been fully identified yet. Consequently, the present study is aimed at exploring potential blood biomarkers by investigating the molecular mechanisms of ERS promoting neuronal apoptosis following IS development. Methods: A comprehensive analysis was performed with two free-accessible whole-blood datasets (GSE16561 and GSE37587) from the Gene Expression Omnibus database. Genetic information from 107 IS and 24 healthy controls was employed to analyze the differentially expressed genes (DEGs). Genes related to ERS (ERS-DEGs) were identified from the analysis. Enrichment analyses were performed to explore the biofunction and correlated signal pathways of ERS-DEGs. Protein-protein interaction (PPI) network and immune correlation analyses were performed to identify the hub genes along with their correspondent expressions and functions, all of which contributed to incremental diagnostic values. Results: A total of 60 IS-related DEGs were identified, of which 27 genes were confirmed as ERS-DEGs. GO and KEGG enrichment analysis corroborated that upregulated ERS-DEGs were principally enriched in pathways related to immunity, including neutrophil activation and Th17 cell differentiation. Moreover, the GSEA and GSVA indicated that T cell-related signal pathways were the most considerably immune pathways for ERS-DEG enrichment. A total of 10 hub genes were filtered out via the PPI network analysis. Immune correlation analysis confirmed that the expression of hub genes is associated with immune cell infiltration. Conclusions: By integrating and analyzing the two gene expression data profiles, it can be inferred that ERS may be involved in the development of neuronal apoptosis following IS via immune homeostasis. The identified hub genes, which are associated with immune cell infiltration, may serve as potential biomarkers for relative diagnosis and therapy.


Assuntos
Redes Reguladoras de Genes , AVC Isquêmico , Biomarcadores , Biologia Computacional , Estresse do Retículo Endoplasmático/genética , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , AVC Isquêmico/genética
19.
Front Cell Neurosci ; 16: 1002671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385944

RESUMO

Hepatic encephalopathy (HE)-a major complication of liver disease-has been found to increase the risk of olfactory dysfunction, which may be attributed to elevated levels of ammonia/ammonium in the blood and cerebrospinal fluid. However, the cellular mechanisms underlying hyperammonemia-induced olfactory dysfunction remain unclear. By performing patch-clamp recordings of mitral cells (MCs) in the mouse olfactory bulb (OB), we found that 3 mM ammonium (NH4 +) increased the spontaneous firing frequency and attenuated the amplitude, but synaptic blockers could prevent the changes, suggesting the important role of glutamate receptors in NH4 +-induced hyperexcitability of MCs. We also found NH4 + reduced the currents of voltage-gated K+ channel (Kv), which may lead to the attenuation of spontaneous firing amplitude by NH4 +. Further studies demonstrated NH4 + enhanced the amplitude and integral area of long-lasting spontaneous excitatory post-synaptic currents (sEPSCs) in acute OB slices. This enhancement of excitatory neurotransmission in MCs occurred independently of pre-synaptic glutamate release and re-uptake, and was prevented by the exocytosis inhibitor TAT-NSF700. In addition, an NH4 +-induced increasement in expression of NR1 and GluR1 was detected on cytoplasmic membrane, indicating that increased trafficking of glutamate receptors on membrane surface in MCs is the core mechanism. Moreover, NH4 +-induced enhanced activity of glutamate receptors in acute OB slices caused cell death, which was prevented by antagonizing glutamate receptors or chelating intracellular calcium levels. Our study demonstrates that the enhancement of the activity and recruitment of glutamate receptor directly induces neuronal excitotoxicity, and contributes to the vulnerability of OB to acute hyperammonemia, thus providing a potential pathological mechanism of olfactory defects in patients with hyperammonemia and HE.

20.
Neurosci Lett ; 784: 136747, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35724761

RESUMO

Nicotinamide adenine dinucleotide (NAD+) is a ubiquitous molecule with wide-ranging roles in several cell processes, such as regulation of calcium homeostasis and protection against cell injuries. However, the roles of NAD+ in neuroprotection is poorly understood. The main neurons in ventral cochlear nucleus (VCN) are highly susceptible to bilirubin-associated excitotoxicity. We investigated the effects of NAD+ on VCN neurons by whole cell patch-clamp recordings. We found that NAD+ effectively reverses and inhibits bilirubin-mediated enhancement of voltage-gated calcium (VGCC) currents in VCN neurons. Moreover, NAD+ itself did not affect VGCC currents. These results collectively suggest that NAD+ may be neuroprotective by attenuating Ca2+ influx to suppress bilirubin-induced intracellular Ca2+ overloads. Our research provides a basis for evaluation of NAD+ as a promising therapeutic target for bilirubin encephalopathy and excitotoxicity associated with other neurological disorders.


Assuntos
Núcleo Coclear , Bilirrubina/farmacologia , Cálcio , NAD/farmacologia , Neurônios
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