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1.
Molecules ; 29(7)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38611861

RESUMO

The use of a surfactant solution during oil and gas field development might improve the recovery rate of oil reservoirs. However, the serious emulsification of the produced liquid will bring challenges to the subsequent treatment process and storage and transportation. It is urgent to understand the coalescence mechanism of crude oil under the action of surfactant solution. This research investigates the coalescence mechanism of numerous oil droplets under liquid flow perturbation. The model was established to study the coalescence process of multiple oil droplets. The effects of the number of oil droplets under homogeneous conditions, the size of oil droplets, and the distance between oil droplets under non-homogeneous conditions on the coalescence process were analyzed. Meanwhile, the change rules of the completion time of oil droplet coalescence were drawn. The results show that the smaller the size of individual oil droplets under non-homogeneous conditions, the longer the coalescence completion time is, and when the size of individual oil droplets reaches the nanometer scale, the time for coalescence of oil droplets is dramatically prolonged. Compared to static circumstances, the time it takes for oil droplets to coalesce is somewhat shorter under gravity. In the fluid flow process, in the laminar flow zone, the coalescence time of oil droplets decreases with the increase of the liquid flow rate. However, in the turbulent flow zone, the coalescence time of oil droplets increases with the increase in the liquid flow rate. The coalescence time is in the range of 600~1000 ms in the flow rate of 0.05~0.2 m/s. In the presence of surfactants, the oil content in the emulsion system increases under the influence of pumping flow. The change in oil content rate with various surfactants is less impacted by flow rate, owing to the stable emulsion structure created by the extracted fluid within the reservoir. The study findings presented in this research provide technical assistance for effective crude oil storage and transportation.

2.
Funct Integr Genomics ; 23(3): 211, 2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37358720

RESUMO

The annexin superfamily (ANXA) is made up of 12 calcium (Ca2+) and phospholipid binding protein members that have a high structural homology and play a key function in cancer cells. However, little research has been done on the annexin family's function in pan-cancer. We examined the ANXA family's expression in various tumors through public databases using bioinformatics analysis, assessed the differences in ANXA expression between tumor and normal tissues in pan-cancer, and then investigated the relationship between ANXA expression and patient survival, prognosis, and clinicopathologic traits. Additionally, we investigated the relationships among TCGA cancers' mutations, tumor mutation burden (TMB), microsatellite instability (MSI), immunological subtypes, immune infiltration, tumor microenvironment, immune checkpoint genes, chemotherapeutics sensitivity, and ANXAs expression. cBioPortal was also used to uncover pan-cancer genomic anomalies in the ANXA family, study relationships between pan-cancer ANXA mRNA expression and copy number or somatic mutations, and assess the prognostic values of these variations. Moreover, we investigated the relationship between ANXAs expression and effectiveness of immunotherapy in multiple cohorts, including one melanoma (GSE78220), one renal cell carcinoma (GSE67501), and three bladder cancer cohorts (GSE111636, IMvigor210 and our own sequencing dataset (TRUCE-01)), and further analyzed the changes of ANXAs expression before and after treatment (tislelizumab combined with nab-paclitaxel) of bladder cancer. Then, we explored the biological function and potential signaling pathway of ANXAs using gene set enrichment analysis (GSEA), and first conducted immune infiltration analysis with ANXAs family genes expression, copy number, or somatic mutations of bladder cancer by TIMER 2.0. Most cancer types and surrounding normal tissues expressed ANXA differently. ANXA expression was linked to patient survival, prognosis, clinicopathologic features, mutations, TMB, MSI, immunological subtypes, tumor microenvironment, immune cell infiltration, and immune checkpoint gene expression in 33 TCGA cancers, with ANXA family members varied. The anticancer drug sensitivity analysis showed that ANXAs family members were significantly related to a variety of drug sensitivities. In addition, we also discovered that the expression level of ANXA1/2/3/4/5/7/9/10 was positively or negatively correlated with objective responses to anti-PD-1/PD-L1 across multiple immunotherapy cohorts. The immune infiltration analysis of bladder cancer further showed the significant relationships between ANXAs copy number variations or mutation status, and infiltration level of different immune cells. Overall, our analyses confirm the importance of ANXAs expression or genomic alterations in prognosis and immunological features of various cancer and identified ANXA-associated genes that may serve as potential therapeutic targets.


Assuntos
Multiômica , Neoplasias da Bexiga Urinária , Humanos , Variações do Número de Cópias de DNA , Imunoterapia , Anexinas , Microambiente Tumoral/genética
3.
Nano Lett ; 22(11): 4528-4534, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35588493

RESUMO

Because of type-II band alignment, interlayer exciton (IX) is found in a van der Waals (vdW) heterostructure (HS) formed by two monolayers of transition-metal dichalcogenides. Manipulation of IXs is of great importance for excitonic integrated devices. Here, we demonstrate that high pressure and tensile strain can be applied to enhance and reduce interlayer coupling of WSe2/WS2 HS, respectively. High pressure induces the transform of intralayer excitons to IX, while tensile strain leads to the transform of IXs to intralayer excitons. In addition, there is a direct-to-indirect band gap transition of WSe2/WS2 HS. The interlayer distance of WSe2/WS2 HS is reduced under high pressure, but it increased under uniaxial tensile strain from first-principles calculations. The calculated band structures explain well the transformation between interlayer and intralayer excitons of WSe2/WS2 HS. This work demonstrates the exchange of interlayer and intralayer excitons and paves the way to manipulate excitons of HS for excitonic applications.

4.
Nano Lett ; 22(14): 5841-5848, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35816385

RESUMO

The giant light-matter interaction induced by van Hove singularities (vHSs) of twisted bilayer graphene (tBLG) is responsible for enhanced optical absorption and strong photoresponse. Here, we investigated the evolution of vHSs in tBLG under pressure by using Raman spectroscopy. Pressure not only induces a blue shift of the G/R band but also tunes the intensity of the G/R band. The blue shift of the G/R band is due to the reduction of the in-plane lattice constant, and the variation of the G/R band intensity is due to the vHSs' shift of tBLG. Moreover, the main band in the absorption spectrum of tBLG is attributed to multiple transitions from valence to conduction bands. Because the ratio of R to G band intensity increases under pressure and the origins of R and G bands are different, we claim that pressure enhances intervalley electron scattering. This study paves the way for pressure engineering of vHS and the corresponding photon-electron-phonon interaction in tBLG.

5.
Cytokine ; 152: 155823, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35183823

RESUMO

Myocarditis is a kind of myocardial inflammatory infiltration disease. Many interventions are not effective in the treatment of myocarditis because the mechanism of myocarditis has not been elucidated. Previous studies have found that interleukin-17 (IL-17) could stimulate the expression of monocyte chemokine protein 1 (MCP-1) and mediate myocardial inflammatory infiltration. This study aimed to explore the role of Act1/TRAF6/TAK1 cascade in IL-17-induced MCP-1 expression based on a well-designed experimental autoimmune myocarditis (EAM) model. It was found that IL-17 could stimulate the expression of MCP-1 by activating Act1/TRAF6/TAK1 cascade in EAM. The expression of Act1, TRAF6 and TAK1 followed downregulation by the application of IL-17 antibody. Additionally, myocardial inflammatory cell infiltration was observably alleviated by interfering TAK1 with TAK1 siRNA, and both MCP-1 mRNA and protein expression followed downregulation. This study suggested that IL-17 could activate the Act1/TRAF6/TAK1 pathway to upregulate MCP-1 expression in the EAM, and will offer a new perspective for the study on the mechanism of myocarditis.


Assuntos
Doenças Autoimunes , Miocardite , Doenças Autoimunes/genética , Quimiocinas/metabolismo , Conexina 43/metabolismo , Humanos , Interleucina-17/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Monócitos/metabolismo , Miocardite/genética , Fragmentos de Peptídeos/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo
6.
J Proteome Res ; 20(5): 2206-2215, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33764076

RESUMO

Glioma is a malignant brain tumor. There is growing evidence that its progression involves altered metabolism. This study's objective was to understand how those metabolic perturbations were manifested in plasma and urine. Metabolic signatures in blood and urine were characterized by liquid chromatography-tandem mass spectrometry. The results were linked to gene expression using data from the Gene Expression Omnibus database. Genes and pathways associated with the disease were thus identified. Forty metabolites were identified, which were differentially expressed in the plasma of glioma patients, and 61 were identified in their urine. Twenty-two metabolites and five disturbed pathways were found both in plasma and urine. Twelve metabolites in plasma and three in urine exhibited good diagnostic potential for glioma. Transcriptomic analyses revealed specific changes in the expression of 1437 genes associated with glioma. Seventeen differentially expressed genes were found to be correlated with four of the metabolites. Enrichment analysis indicated that dysregulation of glutamatergic synapse pathway might affect the pathology of glioma. Integration of metabolomics with transcriptomics can provide both a broad picture of novel cancer signatures and preliminary information about the molecular perturbations underlying glioma. These results may suggest promising targets for developing effective therapies.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica , Glioma/genética , Humanos , Metabolômica , Transcriptoma
7.
J Sep Sci ; 44(19): 3562-3579, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34358407

RESUMO

Zilongjin tablets as a traditional Chinese medicine are widely used for primary lung cancer patients with deficiency of "qi " and "blood " syndrome undergoing chemotherapy. It is a compound preparation that consists of eight herbs. To clarify the chemical profiling of Zilong Jin tablets rapidly, a feasible and accurate strategy was developed by the ultra high performance liquid chromatography-quadrupole/orbitrap high resolution mass spectrometry. According to the accurate mass and fragment ion information provided by high resolution mass spectrometry, the compounds were reasonably identified. In total, 74 compounds were characterized, including 20 flavonoids, 14 quinones, 15 organic acids, 6 phthalide compounds, and 19 other compounds. Among them, 34 major compounds were unambiguously confirmed by comparing with reference standards. This study could provide an important scientific basis for further research on quality control, pharmacokinetics and pharmacodynamics, and clinical application of Zilong Jin tablets.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas/métodos , Benzofuranos/análise , Benzofuranos/química , Flavonoides/análise , Flavonoides/química , Quinonas/análise , Quinonas/química
8.
Mem Cognit ; 49(4): 747-757, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33415712

RESUMO

Recent studies have shown that the temporary storage and manipulation of depth information (working memory for depth; WMd) is largely different from that of visual information in a 2D context (visual working memory; VWM). Although there has been abundant evidence on VWM showing that cueing a memory item during retention could bias attention to its internal representation and thus improves its memory performance (a retro-cue effect), it is unknown whether such an effect differs for WMd that is nested in a 3D context compared with that in a conventional 2D context. Here, we used a change detection task to investigate the effect of attentional selection on WMd by testing several types of retro-cue. The memory array consisted of items positioned at various stereoscopic depth planes, and a cue was presented during retention. Participants needed to make judgments on whether the depth position of target (one memory item) had changed. Our study showed reliable valid retro-cue benefits but no invalid retro-cue cost, indicating that the relational information may be registered in WMd to prevent a strategical removal of the unattended item. There was also a slight improvement in memory performance for cueing depth order compared with that for cueing other feature dimensions or 2D locations. The attentional effect on memory representation in a 3D context is different from that in a 2D context, and the divergence may suggest the distinctive nature of working memory for depth.


Assuntos
Sinais (Psicologia) , Memória de Curto Prazo , Cognição , Humanos , Julgamento , Percepção Visual
9.
J Transl Med ; 18(1): 157, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252780

RESUMO

BACKGROUND: The formal risk assessment is essential in the management of acute coronary syndrome (ACS). In this study, we develop a risk model for the prediction of 3-year mortality for Chinese ACS patients with machine learning algorithms. METHODS: A total of 2174 consecutive patients who underwent angiography with ACS were enrolled. The missing data among baseline characteristics were imputed using the MissForest algorithm based on random forest method. In model development, a least absolute shrinkage and selection operator (LASSO) derived Cox regression with internal tenfold cross-validation was used to identify the predictors for 3-year mortality. The clinical performance was assessed with decision curve analysis. RESULTS: The average follow-up period was 27.82 ± 13.73 months; during the 3 years of follow up, 193 patients died (mortality rate 8.88%). The Kaplan-Meier estimate of 3-year mortality was 0.91 (95% confidence interval (CI): 0.890.92). After feature selection, 6 predictors were identified: Age," "Creatinine," "Hemoglobin," "Platelets," "aspartate transaminase (AST)" and "left ventricular ejection fraction (LVEF)". At tenfold internal validation, our risk model performed well in both discrimination (area under curve (AUC) of receiver operating characteristic (ROC) analysis was 0.768) and calibration (calibration slope was approximately 0.711). As a comparison, the AUC and calibration slope were 0.701 and 0.203 in Global Registry of Acute Coronary Events (GRACE) risk score, respectively. Additionally, the highest net benefit of our model within the entire range of threshold probability for clinical intervention by decision curve analysis demonstrated the superiority of it in daily practice. CONCLUSION: Our study developed a prediction model for 3-year morality in Chinese ACS patients. The methods of missing data imputation and model derivation base on machine learning algorithms improved the ability of prediction. . Trial registration ChiCTR, ChiCTR-OOC-17010433. Registered 17 February 2017-Retrospectively registered.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , China , Humanos , Curva ROC , Medição de Risco , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
10.
Scand J Immunol ; 91(1): e12840, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630418

RESUMO

IL-17 participates in the development of many autoimmune diseases by promoting the expression of some chemokines. Chemokine C-C motif ligand 2 (CCL2) is an important factor at the infiltration of mononuclear cells in the myocardial tissue of viral myocarditis (VMC). It was found that IL-17 could aggravate myocardial injury by upregulating CCL2. But the underlying mechanism involved in CCL2 secretion induced by IL-17 in cardiac myocytes remains unclear. This study investigated the role of transcription factor AP-1 in IL-17 induced CCL2 expression. The results showed that IL-17 mediated the activation of Act1, TRAF6, p38MAPK and c-Jun/AP-1 not Wnt or PI3K signalling pathway to upregulate CCL2 expression in cardiac myocytes. After blocking Act1/TRAF6/p38MAPK cascade and interfering AP-1 with Curcumin or c-Jun siRNA, CCL2 expression induced by IL-17 was significantly attenuated at both mRNA and protein levels. Furthermore, the phosphorylation of c-Jun was suppressed when cardiac myocytes were treated with Act1 siRNA, TRAF6 siRNA, SB203580 (p38MAPK inhibitor) or SP600125 (JNK inhibitor) in cardiac myocytes. In conclusion, IL-17 could stimulate the expression of CCL2 in cardiac myocytes via Act1/TRAF6/p38MAPK-dependent AP-1 activation, which may provide a new target for the diagnosis and treatment of VMC.


Assuntos
Quimiocina CCL2/genética , Regulação da Expressão Gênica , Interleucina-17/metabolismo , Miócitos Cardíacos/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição AP-1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Animais Recém-Nascidos , Quimiocina CCL2/metabolismo , Interleucina-17/farmacologia , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação , Transdução de Sinais/efeitos dos fármacos
11.
J Sep Sci ; 43(5): 978-986, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31867785

RESUMO

Garcinia multiflora is a kind of evergreen tree which is widely distributed in the south of China. However, few researches focused on the constituents in different parts of G. multiflora as well as their potential targets and pathways in vivo. To clarify the chemical constituents of G. multiflora rapidly and predict the potential targets as well as pathways in vivo that this plant may have effects on, a feasible and accurate strategy was developed to identify the chemical constituents in fruits, leaves, and branches of G. multiflora by ultra-high performance liquid chromatography with Q-Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry. Network pharmacology was then employed and a "compounds-targets-diseases" network was established. Sixty-one compounds including polycyclic polyprenylated acylphloroglucinols, xanthones, and flavonoids were finally identified in different parts of G. multiflora, and the contents of seven constituents were quantified, respectively. On the basis of the network pharmacology analysis results, compounds in this plant were speculated to have potential pharmacodynamic effect on cancer, inflammatory, respiratory diseases, cardiovascular diseases, and metabolic diseases. This research will provide a new method for the advanced study on the pharmacodynamic materials basis of G. multiflora, and offer valuable evidences for medicinal purpose of this plant.


Assuntos
Medicamentos de Ervas Chinesas/análise , Garcinia/química , Neoplasias/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Inflamação/tratamento farmacológico , Espectrometria de Massas , Doenças Metabólicas/tratamento farmacológico , Transtornos Respiratórios/tratamento farmacológico
12.
Biomed Chromatogr ; 32(10): e4306, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29879756

RESUMO

Shenkang injection is a traditional Chinese formula with good curative effect on chronic renal failure. In this paper, a novel, rapid and sensitive ultra-high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole Orbitrap high-resolution accurate mass spectrometry was developed and validated for simultaneous determination of seven bioactive constituents of Shenkang injection in rat plasma and tissues after intravenous administration. Acetonitrile was used as a protein precipitation agent in biological samples disposal with carbamazepine as internal standard. The chromatographic separation was carried out on a C18 column with a gradient mobile phase consisting of acetonitrile and water (containing 0.1% formic acid). The MS analysis was performed in the full-scan positive and negative ion mode. The lower limits of quantification for the seven analytes in rat plasma and tissues were 0.1-10 ng/mL. The validated method was successfully applied to tissue distribution and pharmacokinetic studies of Shenkang injection after intravenous administration. The results of the tissue distribution study showed that the high concentrations of seven constituents were primarily in the kidney tract. This is the first report of the application of Q-Orbitrap with full-scan mass spectrometry in tissue distribution and pharmacokinetic studies of Shenkang injection.


Assuntos
Cromatografia Líquida/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/farmacocinética , Espectrometria de Massas/métodos , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/química , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
14.
Microbiol Immunol ; 61(7): 280-286, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28593659

RESUMO

IL-17 plays a key role in a variety of autoimmune diseases. MCP-1 is involved in the infiltration of mononuclear cells of myocardium in VMC. However, the relationship between IL-17 and MCP-1 in myocardial injury remains unclear. In this study, expression of MCP-1 mRNA and protein in cardiac myocytes was detected with qRT-PCR and ELISA, respectively. It was found that IL-17A induced MCP-1 expression in a dose- and time-dependent manner in cardiac myocytes, which could be blocked by IL-17A and IL-17RA neutralizing antibodies. NF-κB p65 and p-p65 protein expression in cardiac myocytes was studied with western blotting. Rates of p-p65 in whole lysates and in nuclear lysates all increased in the first 15 min. Meanwhile, the amount of NF-κB p65 in whole lysates did not change, but the amount of NF-κB p65 in nuclear lysates increased in the first 15 min. Then the optimal sequence and concentration of NF-κB p65 siRNAs was selected. After transfection of 10 nM siRNA-2 of NF-κB p65 into cardiac myocytes before stimulation by IL-17A, expression of MCP-1 mRNA and protein obviously decreased. In conclusion, expression of MCP-1 induced by IL-17 requires NF-κB through the phosphorylation of p65 in cardiac myocytes, which is meaningful to study the onset of chronic viral myocarditis and will provide a new target for the treatment of viral myocarditis.


Assuntos
Quimiocina CCL2/metabolismo , Interleucina-17/farmacologia , Miócitos Cardíacos/metabolismo , NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Células Cultivadas , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/biossíntese , Quimiocina CCL2/imunologia , Relação Dose-Resposta a Droga , Interleucina-17/imunologia , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Miócitos Cardíacos/efeitos dos fármacos , Fosforilação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/farmacologia
15.
J Sep Sci ; 40(22): 4453-4466, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28837751

RESUMO

To clarify and quantify the chemical profile of YiXinShu Tablet rapidly, a feasible and accurate strategy was developed by applying ultra high performance liquid chromatography with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry. A total of 105 components were identified, including 25 phenanthraquinones, 11 lactones, 19 lignans, 24 acids, and 26 other compounds. Among them, 26 major compounds were unambiguously detected by comparing with reference standards. And 19 of these compounds in three batches of YiXinShu Tablet were selected for quantitative determination. (Z)-Ligustilide, salvianic acid A, salvianolic acid A, salvianolic acid B, and rosmarinic acid were abundant in these three batches with contents over 1 mg/g. The established analysis methods were examined to be accurate and feasible. The results show that the ultra high performance liquid chromatography with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry method has a powerful qualitative ability and promising quantitative application.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Fitoquímicos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Padrões de Referência , Reprodutibilidade dos Testes , Comprimidos
16.
Proc Natl Acad Sci U S A ; 111(48): 17170-5, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25404294

RESUMO

Mechanosensitive ion channels are sensors probing membrane tension in all species; despite their importance and vital role in many cell functions, their gating mechanism remains to be elucidated. Here, we determined the conditions for releasing intact mechanosensitive channel of large conductance (MscL) proteins from their detergents in the gas phase using native ion mobility-mass spectrometry (IM-MS). By using IM-MS, we could detect the native mass of MscL from Escherichia coli, determine various global structural changes during its gating by measuring the rotationally averaged collision cross-sections, and show that it can function in the absence of a lipid bilayer. We could detect global conformational changes during MscL gating as small as 3%. Our findings will allow studying native structure of many other membrane proteins.


Assuntos
Ativação do Canal Iônico/fisiologia , Canais Iônicos/metabolismo , Espectrometria de Massas/métodos , Mecanotransdução Celular/fisiologia , Detergentes/química , Escherichia coli/metabolismo , Escherichia coli/fisiologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/fisiologia , Proteínas de Escherichia coli/ultraestrutura , Canais Iônicos/química , Canais Iônicos/fisiologia , Canais Iônicos/ultraestrutura , Proteínas de Membrana/química , Proteínas de Membrana/fisiologia , Proteínas de Membrana/ultraestrutura , Microscopia Eletrônica , Simulação de Dinâmica Molecular , Octoxinol/química , Conformação Proteica
17.
Sci Rep ; 14(1): 5957, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472418

RESUMO

Rate of penetration (ROP) is a key factor in drilling optimization, cost reduction and drilling cycle shortening. Due to the systematicity, complexity and uncertainty of drilling operations, however, it has always been a problem to establish a highly accurate and interpretable ROP prediction model to guide and optimize drilling operations. To solve this problem in the Tarim Basin, this study proposes four categories of hybrid physics-machine learning (ML) methods for modeling. One of which is residual modeling, in which an ML model learns to predict errors or residuals, via a physical model; the second is integrated coupling, in which the output of the physical model is used as an input to the ML model; the third is simple average, in which predictions from both the physical model and the ML model are combined; and the last is bootstrap aggregating (bagging), which follows the idea of ensemble learning to combine different physical models' advantages. A total of 5655 real data points from the Halahatang oil field were used to test the performance of the various models. The results showed that the residual modeling model, with an R2 of 0.9936, had the best performance, followed by the simple average model and bagging with R2 values of 0.9394 and 0.5998, respectively. From the view of prediction accuracy, and model interpretability, the hybrid physics-ML model with residual modeling is the optimal method for ROP prediction.

18.
Int J Biol Macromol ; 259(Pt 2): 129310, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216014

RESUMO

Developing biobased materials is a considerably effective approach to save fossil resources and reduce emissions. Biobased polyamide 56 (PA56) is an excellent engineering material, but it has low toughness. Herein, to enhance the toughness of PA56, an ultra-tough biodegradable material, i.e., poly (butylene adipate-co-terephthalate) (PBAT) was introduced into PA56. Moreover, a self-synthesized epoxy-terminated hyperbranched polyester (EHBP) was used to improve the compatibility of the blended materials. The results of differential scanning calorimetry and Fourier-transform infrared spectroscopy indicated that the epoxide group of EHBP could react with PA56 and PBAT to form a block-like polymer structure and limit the crystallization behavior of the blends. The scanning electron microscopy results show that the addition of EHBP considerably reduced the dispersed-phase size in the blends, forming a nanoscale island structure. Moreover, the hydrogen bonds formed between EHBP and PA56/PBAT enhanced the intermolecular interaction between the two materials. Thus, PA56 blends with ultrahigh toughness were successfully prepared. The prepared PA56/PBAT/EHBP blend exhibited a notch impact strength of 20.71 kJ/m2 and a breaking elongation of 38.3 %, which represent increases of 427.3 % and 252.8 %, respectively, compared with those of pure PA56. Thus, the proposed method is suitable for toughening PA56 and broadening its applications.


Assuntos
Alcenos , Nylons , Ácidos Ftálicos , Polímeros , Poliésteres , Adipatos , Poli A
19.
Sci Total Environ ; 928: 172364, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38614347

RESUMO

Determining whether and to what extent the relative abundance of heavy minerals in original detrital assemblage has been modified by mechanical transport is beneficial for understanding regional historical climate changes and acquiring modern sediment provenance information. Utilizing the frequency of surface mechanical optical textures of heavy minerals may be an effective approach to address this question. However, the connection between the frequency surface mechanical optical textures of heavy minerals and the variations in the relative abundance of these minerals remains uncertain. In this study, 12 modern aeolian sand samples were collected from the Badain Jaran Desert in hyper arid region of northwestern China, characterized by weak weathering to analyze their relative contents of five major heavy minerals. Then, 3796 transparent heavy mineral grains were photographed under the parallel light of a polarizing microscope, and the frequency of 13 surface mechanical optical textures were calculated. The results reveal that the variations in the relative abundance of heavy minerals are substantially influenced by mechanical transport. The decrease in the relative abundance of heavy minerals with weak mechanical stability primarily attributed to mechanical collision. Conversely, the variations in the relative abundance of heavy minerals with strong mechanical stability are primarily influenced by mechanical abrasion. Therefore, mechanical transport impact on the relative abundance of heavy minerals in regions with weak chemical weathering. Establishing heavy mineral characteristic indices for provenance studies using the relative abundance of mechanically unstable minerals may not directly indicate transport distance but rather the strength of wind forces, which have significant potential in palaeo wind regime studies. This study expands the research field of sediment surface micromorphology and has potential applications in inferring past climate changes and determining modern sediment provenance.

20.
Int Immunopharmacol ; 139: 112716, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39038386

RESUMO

BACKGROUND: Prolonged exposure to interleukin-17A (IL-17A) can induce autoimmune myocarditis, and MLN4924, an inhibitor of NEDD8 activating enzyme (NAE), has been reported to effectively suppress various inflammatory reactions. However, the effects of MLN4924 in IL-17A-mediated inflammation associated with autoimmune myocarditis remain uncertain. METHODS: An experimental autoimmune myocarditis (EAM) model was established and treated with MLN4924. The inflammation degree of heart tissues was assessed histopathologically. The expression levels of inflammatory cytokines and chemokines were measured using ELISA and RT-qPCR, respectively. Additionally, the interaction of biomacromolecules was detected through co-immunoprecipitation (Co-IP) and RNA immunoprecipitation (RIP). RESULTS: MLN4924 could attenuate IL-17A-induced inflammation. In the in vivo studies, MLN4924 treatment improved inflammatory responses, diminished immune cell infiltration and tissue fibrosis, and reduced the secretion of various inflammatory cytokines in serum, including IL-1ß, IL-6, TNF-α, and MCP-1. In vitro experiments further corroborated these findings, showing that MLN4924 treatment reduced the secretion and transcription of pro-inflammatory factors, particularly MCP-1. Mechanistically, we confirmed that MLN4924 promoted Act1 ubiquitination degradation and disrupted Act1's interaction with IL-17R, thereby impeding the formation of the IL-17R/Act1/TRAF6 complex and subsequent activation of TAK1, c-Jun, and p65. Moreover, MLN4924 interfered with Act1's binding to mRNA, resulting in mRNA instability. CONCLUSIONS: In conclusion, MLN4924 effectively alleviated inflammatory symptoms in EAM by disrupting the interaction between IL and 17R and Act1, thereby reducing Act1-mediated mRNA stability and resulting in decreased expression of pro-inflammatory factors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Doenças Autoimunes , Ciclopentanos , Citocinas , Miocardite , Pirimidinas , Estabilidade de RNA , Animais , Miocardite/tratamento farmacológico , Miocardite/imunologia , Miocardite/metabolismo , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ciclopentanos/farmacologia , Ciclopentanos/uso terapêutico , Camundongos , Estabilidade de RNA/efeitos dos fármacos , Masculino , Citocinas/metabolismo , Interleucina-17/metabolismo , Modelos Animais de Doenças , Humanos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , RNA Mensageiro/metabolismo , Camundongos Endogâmicos BALB C
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