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1.
Proc Natl Acad Sci U S A ; 119(13): e2025606119, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35312361

RESUMO

SignificanceThe permanent disappearance of mass-independent sulfur isotope fractionation (S-MIF) from the sedimentary record has become a widely accepted proxy for atmospheric oxygenation. This framework, however, neglects inheritance from oxidative weathering of pre-existing S-MIF-bearing sedimentary sulfide minerals (i.e., crustal memory), which has recently been invoked to explain apparent discrepancies within the sulfur isotope record. Herein, we demonstrate that such a crustal memory effect does not confound the Carletonville S-isotope record; rather, the pronounced Δ33S values identified within the Rooihoogte Formation represent the youngest known unequivocal oxygen-free photochemical products. Previously observed 33S-enrichments within the succeeding Timeball Hill Formation, however, contrasts with our record, revealing kilometer-scale heterogeneities that highlight significant uncertainties in our understanding of the dynamics of Earth's oxygenation.

2.
J Mol Cell Cardiol ; 191: 76-87, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718920

RESUMO

The reactivated adult epicardium produces epicardium-derived cells (EPDCs) via epithelial-mesenchymal transition (EMT) to benefit the recovery of the heart after myocardial infarction (MI). SMARCA4 is the core catalytic subunit of the chromatin re-modeling complex, which has the potential to target some reactivated epicardial genes in MI. However, the effects of epicardial SMARCA4 on MI remain uncertain. This study found that SMARCA4 was activated over time in epicardial cells following MI, and some of activated cells belonged to downstream differentiation types of EPDCs. This study used tamoxifen to induce lineage tracing and SMARCA4 deletion from epicardial cells in Wt1-CreER;Smarca4fl/fl;Rosa26-RFP adult mice. Epicardial SMARCA4 deletion reduces the number of epicardial cells in adult mice, which was related to changes in the activation, proliferation, and apoptosis of epicardial cells. Epicardial SMARCA4 deletion reduced collagen deposition and angiogenesis in the infarcted area, exacerbated cardiac injury in MI. The exacerbation of cardiac injury was related to the inhibition of generation and differentiation of EPDCs. The alterations in EPDCs were associated with inhibited transition between E-CAD and N-CAD during the epicardial EMT, coupled with the down-regulation of WT1, SNAIL1, and PDGF signaling. In conclusion, this study suggests that Epicardial SMARCA4 plays a critical role in cardiac injury caused by MI, and its regulatory mechanism is related to epicardial EMT. Epicardial SMARCA4 holds potential as a novel molecular target for treating MI.


Assuntos
DNA Helicases , Transição Epitelial-Mesenquimal , Deleção de Genes , Infarto do Miocárdio , Pericárdio , Fatores de Transcrição , Animais , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Transição Epitelial-Mesenquimal/genética , Pericárdio/patologia , Pericárdio/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , DNA Helicases/genética , DNA Helicases/metabolismo , Camundongos , Diferenciação Celular , Apoptose/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/deficiência , Proliferação de Células , Modelos Animais de Doenças
3.
Opt Express ; 32(9): 15993-16003, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859237

RESUMO

As the semiconductor technology node continues to shrink, achieving smaller critical dimension in lithography becomes increasingly challenging. Negative tone development (NTD) process is widely employed in advanced node due to their large process window. However, the unique characteristics of NTD, such as shrinkage effect, make the NTD resist model calibration more complex. Gradient descent (GD) and heuristic methods have been applied for calibration of NTD resist model. Nevertheless, these methods depend on initial parameter selection and tend to fall into local optima, resulting in poor accuracy of the NTD model and massive computational time. In this paper, we propose cluster sampling and scalable Bayesian optimization (BO) with constraints method for NTD resist model calibration. This approach utilizes cluster sampling strategy to enhance the capability for global initial sampling and employs scalable BO with constraints for global optimization of high-dimensional parameter space. With this approach, the calibration accuracy is significantly enhanced in comparison with results from GD and heuristic methods, and the computational efficiency is substantially improved compared with GD. By gearing up cluster sampling strategy and scalable BO with constraints, this method offers a new and efficient resist model calibration.

4.
Chemistry ; 30(11): e202303505, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38143237

RESUMO

The catalysis performance of metal nanoparticles (NPs) will be significantly deteriorated because of their spontaneous agglomeration during practical applications. Covalent-organic frameworks (COFs) materials with functional groups and well-defined channels benefit for the dispersion and anchor of metal ions and the confined growth of metal NPs, working as an ideal platform to compose catalytic systems. In this article, we report a one-pot strategy for the preparation of metal NPs loaded COFs without the need of post-modification. During the polymerization process, the pre-added metal ions were stabilized by the rapidly formed COF oligomers and hardly disturb the construction of COFs. After reduction, metal NPs are uniformly anchored on the COF matrix. Eventually, a wide spectrum of metal NPs, including Au, Pd, Pt, AuPd, CuPd, CuPt and CuPdPt, loaded COFs are successfully prepared. The versatility and metal ions anchoring mechanism are verified with four different COF matrixes. Taking AuPd NPs as example, the resultant AuPd NPs loaded COF materials can selectively decompose ammonium formate and produce hydrogen in-situ, exhibiting over 99 % conversion of hydrodechlorination for chlorobenzenes and nitro-reduction reaction for nitroaromatic compounds under ambient temperature in aqueous solution.

5.
Langmuir ; 40(17): 9001-9011, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38627239

RESUMO

The enrichment and recovery of gold from wastewater are an alternative method to obtain this noble metal, which benefits reducing hazardous emissions from the conventional ore mining process and reserving natural gold for sustainable development. Inspired by our previous work (Lei et al., Macromol. Rapid Comm. 2022, 2200712), four families of microporous polyureas (mPPUs) with a large surface area (690 m2 g-1) and abundant heteroatom sites have been prepared via the factor-optimized solvothermal protocol. The resultant sample NPU-A starting from 1,5-naphthalene diisocyanate (NDI) and tri(4-aminophenyl) amine (TAPA) exhibits the maximum Au(III) adsorption capacity of 1300 mg g-1 and high selectivity even when the Au(III) concentration is as low as 0.1 mg L-1. This study not only demonstrates the robustness of the high-throughput synthetic strategy but also promotes the investigation of the structure-activity correlation between the mPPU chemical structure and Au(III) adsorption performance.

6.
Int J Legal Med ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38802694

RESUMO

In forensic practice, determining the postmortem submersion interval (PMSI) and cause-of-death of cadavers in aquatic ecosystems has always been challenging task. Traditional approaches are not yet able to address these issues effectively and adequately. Our previous study proposed novel models to predict the PMSI and cause-of-death based on metabolites of blood from rats immersed in freshwater. However, with the advance of putrefaction, it is hardly to obtain blood samples beyond 3 days postmortem. To further assess the feasibility of PMSI estimation and drowning diagnosis in the later postmortem phase, gastrocnemius, the more degradation-resistant tissue, was collected from drowned rats and postmortem submersion model in freshwater immediately after death, and at 1 day, 3 days, 5 days, 7 days, and 10 days postmortem respectively. Then the samples were analyzed with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to investigate the dynamic changes of the metabolites. A total of 924 metabolites were identified. Similar chronological changes of gastrocnemius metabolites were observed in the drowning and postmortem submersion groups. The difference in metabolic profiles between drowning and postmortem submersion groups was only evident in the initial 1 day postmortem, which was faded as the PMSI extension. Nineteen metabolites representing temporally-dynamic patterns were selected as biomarkers for PMSI estimation. A regression model was built based on these biomarkers with random forest algorithm, which yielded a mean absolute error (± SE) of 5.856 (± 1.296) h on validation samples from an independent experiment. These findings added to our knowledge of chronological changes in muscle metabolites from submerged vertebrate remains during decomposition, which provided a new perspective for PMSI estimation.

7.
Environ Sci Technol ; 58(18): 8043-8052, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38648493

RESUMO

Bisphenol A (BPA), as a typical leachable additive from microplastics and one of the most productive bulk chemicals, is widely distributed in sediments, sewers, and wastewater treatment plants, where active sulfur cycling takes place. However, the effect of BPA on sulfur transformation, particularly toxic H2S production, has been previously overlooked. This work found that BPA at environmentally relevant levels (i.e., 50-200 mg/kg total suspended solids, TSS) promoted the release of soluble sulfur compounds and increased H2S gas production by 14.3-31.9%. The tryptophan-like proteins of microbe extracellular polymeric substances (EPSs) can spontaneously adsorb BPA, which is an enthalpy-driven reaction (ΔH = -513.5 kJ mol-1, ΔS = -1.60 kJ mol-1K -1, and ΔG = -19.52 kJ mol-1 at 35 °C). This binding changed the composition and structure of EPSs, which improved the direct electron transfer capacity of EPSs, thereby promoting the bioprocesses of organic sulfur hydrolysis and sulfate reduction. In addition, BPA presence enriched the functional microbes (e.g., Desulfovibrio and Desulfuromonas) responsible for organic sulfur mineralization and inorganic sulfate reduction and increased the abundance of related genes involved in ATP-binding cassette transporters and sulfur metabolism (e.g., Sat and AspB), which promoted anaerobic sulfur transformation. This work deepens our understanding of the interaction between BPA and sulfur transformation occurring in anaerobic environments.


Assuntos
Enxofre , Enxofre/metabolismo , Anaerobiose , Sulfeto de Hidrogênio/metabolismo , Fenóis/metabolismo , Compostos Benzidrílicos/metabolismo
8.
Nano Lett ; 23(2): 685-693, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36594847

RESUMO

While tuning the electronic structure of Pt can thermodynamically alleviate CO poisoning in direct methanol fuel cells, the impact of interactions between intermediates on the reaction pathway is seldom studied. Herein, we contrive a PtBi model catalyst and realize a complete inhibition of the CO pathway and concurrent enhancement of the formate pathway in the alkaline methanol electrooxidation. The key role of Bi is enriching OH adsorbates (OHad) on the catalyst surface. The competitive adsorption of CO adsorbates (COad) and OHad at Pt sites, complementing the thermodynamic contribution from alloying Bi with Pt, switches the intermediate from COad to formate that circumvents CO poisoning. Hence, 8% Bi brings an approximately 6-fold increase in activity compared to pure Pt nanoparticles. This notion can be generalized to modify commercially available Pt/C catalysts by a microwave-assisted method, offering opportunities for the design and practical production of CO-tolerance electrocatalysts in an industrial setting.

9.
J Proteome Res ; 22(3): 802-811, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36716354

RESUMO

Multitarget bioactive molecules (MBMs) are of increasing importance in drug discovery as they could produce high efficacy and a low chance of resistance. Several advanced approaches of quantitative proteomics were developed to accurately identify the protein targets of MBMs, but little study has been carried out in a sequential manner to identify primary protein targets (PPTs) of MBMs. This set of proteins will first interact with MBMs in the temporal order and play an important role in the mode of action of MBMs, especially when MBMs are at low concentrations. Herein, we describe a valuable observation that the result of the enrichment process is highly dependent on concentrations of the probe and the proteome. Interestingly, high concentrations of probe and low concentrations of incubated proteome will readily miss the hyper-reactive protein targets and thereby increase the probability of rendering PPTs with false-negative results, while low concentrations of probe and high concentrations of incubated proteome more than likely will capture the PPTs. Based on this enlightening observation, we developed a proof-of-concept approach to identify the PPTs of iodoacetamide, a thiol-reactive MBM. This study will deepen our understanding of the enrichment process and improve the accuracy of pull-down-guided target identification.


Assuntos
Proteoma , Proteoma/metabolismo , Descoberta de Drogas
10.
J Am Chem Soc ; 145(48): 26374-26382, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37992232

RESUMO

The electrochemical conversion of CO2 into multicarbon (C2) products on Cu-based catalysts is strongly affected by the surface coverage of adsorbed CO (*CO) intermediates and the subsequent C-C coupling. However, the increased *CO coverage inevitably leads to strong *CO repulsion and a reduced C-C coupling efficiency, thus resulting in suboptimal CO2-to-C2 activity and selectivity, especially at ampere-level electrolysis current densities. Herein, we developed an atomically ordered Cu9Ga4 intermetallic compound consisting of Cu square-like binding sites interspaced by catalytically inert Ga atoms. Compared to Cu(100) previously known with a high C2 selectivity, the Ga-spaced, square-like Cu sites presented an elongated Cu-Cu distance that allowed to reduce *CO repulsion and increased *CO coverage simultaneously, thus endowing more efficient C-C coupling to C2 products than Cu(100) and Cu(111). The Cu9Ga4 catalyst exhibited an outstanding CO2-to-C2 electroreduction, with a peak C2 partial current density of 1207 mA cm-2 and a corresponding Faradaic efficiency of 71%. Moreover, the Cu9Ga4 catalyst demonstrated a high-power (∼200 W) electrolysis capability with excellent electrochemical stability.

11.
BMC Plant Biol ; 23(1): 188, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37032339

RESUMO

BACKGROUND: Phosphorus (P) deficiency in desert ecosystems is widespread. Generally, desert species may allocate an enormous proportion of photosynthetic carbon to their root systems to adjust their P-acquisition strategies. However, root P-acquisition strategies of deep-rooted desert species and the coordination response of root traits at different growth stages to differing soil P availability remains unclear. In this study, a two-year pot experiment was performed with four soil P-supply treatments (0, 0.9, 2.8, and 4.7 mg P kg-1 y-1 for the control, low-, intermediate-, and high-P supply, respectively). Root morphological and physiological traits of one- and two-year-old Alhagi sparsifolia seedlings were measured. RESULTS: For two-year-old seedlings, control or low-P supply significantly increased their leaf Mn concentration, coarse and fine roots' specific root length (SRL), specific root surface area (SRSA), and acid phosphatase activity (APase), but SRL and SRSA of one-year-old seedlings were higher under intermediate-P supply treatment. Root morphological traits were closely correlated with root APase activity and leaf Mn concentration. One-year-old seedlings had higher root APase activity, leaf Mn concentration, and root tissue density (RTD), but lower SRL and SRSA. Two-year-old seedlings had higher root APase activity, leaf Mn concentration, SRL and SRSA, but a lower RTD. Root APase activity was significantly positively correlated with the leaf Mn concentration, regardless of coarse or fine roots. Furthermore, root P concentrations of coarse and fine roots were driven by different root traits, with root biomass and carboxylates secretion particularly crucial root traits for the root P-acquisition of one- and two-year-old seedlings. CONCLUSIONS: Variation of root traits at different growth stages are coordinated with root P concentrations, indicating a trade-off between root traits and P-acquisition strategies. Alhagi sparsifolia developed two P-activation strategies, increasing P-mobilizing phosphatase activity and carboxylates secretion, to acclimate P-impoverished in soil. The adaptive variation of root traits at different growth stages and diversified P-activation strategies are conducive to maintaining the desert ecosystem productivity.


Assuntos
Ecossistema , Fabaceae , Fósforo , Solo , Raízes de Plantas , Plantas , Plântula , Ácidos Carboxílicos
12.
Chemistry ; 29(16): e202203142, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36565275

RESUMO

Enhancing catalytic performance as well as reducing catalyst cost are the eternal pursuit for the catalysis community. Herein, a simple and effective palladium-doped cobalt (Pd/Co) catalyst with high Pd atom utilization efficiency was synthesized via galvanic replacement reaction for the selective hydrogenation of nitrobenzene with H2 at room temperature, delivering >99 % yield of aniline with up to 158 times higher catalytic activity than commercial palladium powder. Detailed characterizations and DFT calculations revealed that Co-Pd interaction leads to a decrease in electron density of Pd and the distance between Pd atoms that results in the enhanced catalytic performance. Further experiments indicated that the Pd/Co catalyst serves as a highly efficient, selective, and recyclable catalyst for a range of nitroarene substrates. This work might provide a green and sustainable methodology to design and synthesize highly active catalysts with high utilization efficiency of the noble metals in fundamental and applied research.

13.
J Org Chem ; 88(7): 4359-4371, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36939669

RESUMO

Herein, hypervalent iodine-catalyzed halogenation of aryl-activated alkenes using BX3 (X = Cl, Br) as the halogen source and activating reagents was reported. Various halogenated 1,3-oxazine/2-oxazoline derivatives were obtained in good-to-high yields. Using BF3 resulted in different substitute sites from BBr3 and BCl3 of the products, indicating different reactive intermediates and reaction pathways. The reaction underwent a "ligand coupling/oxidative addition/intermolecular nucleophilic attack/1,2-aryl migration/reductive elimination/intramolecular nucleophilic attack" cascade when BF3 was applied as the halogen source, while 1,2-aryl migration has "disappeared" when the halogen source was BBr3 or BCl3. Possible catalytic cycles were proposed, and DFT calculations were conducted to demonstrate the differences among BX3 (X = F, Cl, Br) in the hypervalent iodine-catalyzed halogenations.

14.
Cell Biol Toxicol ; 39(4): 1433-1452, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36121554

RESUMO

T helper (Th) 17 cells highly contribute to the immunopathology of rheumatoid arthritis. Morin, a natural flavonoid, owns well anti-arthritic action but unclear effect on Th17 differentiation. This study tried to solve this issue and explore the mechanisms in view of cellular metabolism. Naïve CD4+ T cells were treated with anti-CD3/CD28 along with Th17-inducing cytokines. Morin was shown to block Th17 differentiation without affecting cell viability even when Foxp3 was dampened. The mechanisms were ascribed to the limited fatty acid synthesis by restricting FASN transcription, as indicated by metabolomics analysis, nile red staining, detection of triglycerides, FASN overexpression, and addition of palmitic acid. Moreover, morin had slight effect on cell apoptosis and protein palmitoylation during Th17 differentiation, but blocked the binding of RORγt to promoter and CNS2 region of Il17a gene. Oleic acid rescued the inhibition of morin on RORγt function, and Th17-inducing cytokines could not induce RORγt function in SCD1-defficient cells, suggesting that oleic acid but not palmitic acid was the direct effector in the action of morin. Then, PPARγ was identified as the target of morin, and GW9662 or PPARγ CRISPR/Cas9 KO plasmid weakened its above-mentioned effects. The transrepression of FASN by morin was owing to physical interaction between PPARγ and Sp1, and the importance of Sp1 in Th17 differentiation was confirmed by siSp1. Finally, the effects and mechanisms for morin-dampened Th17 responses were confirmed in collagen-induced arthritis (CIA) mice. Collectively, morin inhibited Th17 differentiation and alleviated CIA by limiting fatty acid synthesis subsequent to PPARγ activation.


Assuntos
Artrite Experimental , Camundongos , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Artrite Experimental/patologia , PPAR gama/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Agonistas PPAR-gama , Ácido Oleico , Diferenciação Celular , Citocinas , Flavonoides/farmacologia
15.
Arch Toxicol ; 97(2): 441-456, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336710

RESUMO

Cisplatin is recommended as a first-line chemotherapeutic agent against advanced non-small cell lung cancer (NSCLC), but acquired resistance substantially limits its clinical efficacy. Recently, DNA methylation has been identified as an essential contributor to chemoresistance. However, the precise DNA methylation regulatory mechanism of cisplatin resistance remains unclear. Here, we found that nicotinamide nucleotide transhydrogenase (NNT) was silenced by DNA hypermethylation in cisplatin resistance A549 (A549/DDP) cells. Also, the DNA hypermethylation of NNT was positively correlated to poor prognosis in NSCLC patients. Overexpression of NNT in A549/DDP cells could reduce their cisplatin resistance, and also suppressed their tumor malignancy such as cell proliferation and clone formation. However, NNT enhanced sensitivity of A549/DDP cells to cisplatin had little to do with its function in mediating NADPH and ROS level, but was mainly because NNT could inhibit protective autophagy in A549/DDP cells. Further investigation revealed that NNT could decrease NAD+ level, thereby inactivate SIRT1 and block the autophagy pathway, while re-activation of SIRT1 through NAD+ precursor supplementation could antagonize this effect. In addition, targeted demethylation of NNT CpG island via CRISPR/dCas9-Tet1 system significantly reduced its DNA methylation level and inhibited the autophagy and cisplatin resistance in A549/DDP cells. Thus, our study found a novel chemoresistance target gene NNT, which played important roles in cisplatin resistance of lung cancer cells. Our findings also suggested that CRISPR-based DNA methylation editing of NNT could be a potential therapeutics method in cisplatin resistance of lung cancer.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , NADP Trans-Hidrogenases , Humanos , Células A549 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Autofagia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células , Cisplatino/farmacologia , DNA , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , NAD/metabolismo , NADP Trans-Hidrogenases/genética , NADP Trans-Hidrogenases/metabolismo , Sirtuína 1/metabolismo
16.
Appl Opt ; 62(33): 8769-8779, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38038022

RESUMO

As the feature size of integrated circuits continues to decrease, optical proximity correction (OPC) has emerged as a crucial resolution enhancement technology for ensuring high printability in the lithography process. Recently, level set-based inverse lithography technology (ILT) has drawn considerable attention as a promising OPC solution, showcasing its powerful pattern fidelity, especially in advanced processing. However, the massive computational time consumption of ILT limits its applicability to mainly correcting partial layers and hotspot regions. Deep learning (DL) methods have shown great potential in accelerating ILT. However, the lack of domain knowledge of inverse lithography limits the ability of DL-based algorithms in process window (PW) enhancement, etc. In this paper, we propose an inverse lithography physics-informed deep neural level set (ILDLS) approach for mask optimization. This approach utilizes level set-based ILT as a layer within the DL framework and iteratively conducts mask prediction and correction to significantly enhance printability and PW in comparison with results from pure DL and ILT. With this approach, the computational efficiency is significantly improved compared with ILT. By gearing up DL with the knowledge of inverse lithography physics, ILDLS provides a new and efficient mask optimization solution.

17.
Proc Natl Acad Sci U S A ; 117(21): 11233-11239, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393637

RESUMO

Pulsating flows through tubular geometries are laminar provided that velocities are moderate. This in particular is also believed to apply to cardiovascular flows where inertial forces are typically too low to sustain turbulence. On the other hand, flow instabilities and fluctuating shear stresses are held responsible for a variety of cardiovascular diseases. Here we report a nonlinear instability mechanism for pulsating pipe flow that gives rise to bursts of turbulence at low flow rates. Geometrical distortions of small, yet finite, amplitude are found to excite a state consisting of helical vortices during flow deceleration. The resulting flow pattern grows rapidly in magnitude, breaks down into turbulence, and eventually returns to laminar when the flow accelerates. This scenario causes shear stress fluctuations and flow reversal during each pulsation cycle. Such unsteady conditions can adversely affect blood vessels and have been shown to promote inflammation and dysfunction of the shear stress-sensitive endothelial cell layer.

18.
Fa Yi Xue Za Zhi ; 39(6): 596-600, 2023 Dec 25.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38228479

RESUMO

Wound age estimation is the core content in the practice of forensic medicine. Accurate estimation of wound age is a scientific question that needs to be urgently solved by forensic scientists at home and abroad. Metabolomics techniques can effectively detect endogenous metabolites produced by internal or external stimulating factors and describe the dynamic changes of metabolites in vivo. It has the advantages of strong operability, high detection efficiency and accurate quantitative results. Machine learning algorithm has special advantages in processing high-dimensional data sets, which can effectively mine biological information and truly reflect the physiological, disease or injury state of the body. It is a new technical means for efficiently processing high-throughput big data. This paper reviews the status and advantages of metabolomic techniques combined with machine learning algorithm in the research of wound age estimation, and provides new ideas for this research.


Assuntos
Algoritmos , Aprendizado de Máquina , Medicina Legal , Metabolômica , Big Data
19.
Insect Mol Biol ; 31(5): 647-658, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35652818

RESUMO

The biosynthesis and termination of insect sex pheromones should be accurately regulated. In most moths, the biosynthesis and release of sex pheromones are regulated by a class of neuropeptides known as pheromone biosynthesis activating neuropeptides (PBANs). However, endogenous mechanisms underlying the termination of sex pheromone biosynthesis in moths remain elusive. In the present study, Helicoverpa armigera was employed as a model to investigate the role of octopamine (OA) in the inhibition of sex pheromone biosynthesis. Results demonstrated that the release of sex pheromones decreased with an increase in OA titres in older female moths. Moreover, OA treatment led to a significant decrease in sex pheromone production, female capability to attract male counterparts and subsequent female acceptance, indicating its inhibitory role in sex pheromone release. Subsequent qPCR and RNAi analyses revealed that OctßR was a key receptor of OA that regulated sex pheromone biosynthesis. In addition, the OA/OctßR signal suppressed intracellular Ca2+ levels and attenuated PBAN-mediated increase in the enzyme activities of calcineurin and acetyl-CoA carboxylase as demonstrated by OA treatment and OctßR-RNAi. Altogether, these results revealed a mechanism underlying the inhibition of sex pheromone production by OA via suppression of PBAN signalling in moths.


Assuntos
Mariposas , Neuropeptídeos , Atrativos Sexuais , Animais , Calcineurina , Feminino , Masculino , Mariposas/genética , Neuropeptídeos/genética , Octopamina
20.
Toxicol Appl Pharmacol ; 449: 116109, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35688185

RESUMO

Airborne nano-scale particulate matter (nPM) exposure is a risk factor for neurological diseases. However, to date, there has been no comprehensive evaluation of ambient nPM's neurotoxicity. We examined the toxic effects of nPM on human neurons derived from induced pluripotent stem cells (iPSCs) at doses ranging from 0 to 200 µg/mL, and employed whole-genome RNA-sequencing in different dose groups to gain further insight into the neurotoxicity of ambient nPM. Our findings showed that nPM was absorbed by neurons, and induced a variety of toxic effects. The apical benchmark dose lower confidence bound (aBMDL) values of each effect endpoint were ranked as follows, in ascending order: mitochondrial membrane potential, neurite length, early apoptosis, cell viability. BMD analysis based on transcriptomic data revealed that the point of departure (PoD) of the 20 pathways with the lowest p-values (0.75 µg/mL), the top 20 upstream regulators (0.79 µg/mL) and the neurological diseases (0.77 µg/mL) could be appropriate for nPM neurotoxicity evaluation. The transcriptomic PoDs (tPoDs) were similar to apical PoDs (aPoDs) since their absolute fold differences were within 10-fold. Further analysis of the transcriptomic data revealed that nPM exposure could disturb the pathways related to ferroptosis, neurotransmitters, xenobiotic metabolism, etc., which might be critical in regulating nPM neurotoxicity. We also found that low-dose nPM induced cytokine signaling pathways, while high doses of nPM activated cell-cycle regulation and DNA repair pathways. Our results indicate that BMD modeling based on transcriptomic data could be useful in illustrating the neurotoxic mechanism, and also could be a promising method for evaluating the potential health risks of nPM.


Assuntos
Células-Tronco Pluripotentes Induzidas , Síndromes Neurotóxicas , Benchmarking , Humanos , Neurônios , Síndromes Neurotóxicas/genética , Material Particulado/toxicidade , Transcriptoma
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