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1.
J Colloid Interface Sci ; 606(Pt 1): 204-212, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388571

RESUMO

Exploring high-efficiency metal-free electrocatalysts towards N2 reduction reaction (NRR) is of great interest for the development of electrocatalytic N2 fixation technology. Herein, we combined boron nitride quantum dots (BNQDs) and graphitic carbon nitride (C3N4) to design a metal-free BNQDs/C3N4 heterostructure as an effective and durable NRR catalyst. The electronically coupled BNQDs/C3N4 presented an NH3 yield as high as 72.3 µg h-1 mg-1 (-0.3 V) and a Faradaic efficiency of 19.5% (-0.2 V), far superior to isolated BNQDs and C3N4, and outperforming nearly all previously reported metal-free catalysts. Theoretical computations unveiled that the N2 activation could be drastically enhanced at the BNQDs-C3N4 interface where interfacial BNQDs and C3N4 cooperatively adsorb N2 and stabilize *N2H intermediate, leading to the significantly promoted NRR process with an ultra-low overpotential of 0.23 V.

2.
J Hazard Mater ; 423(Pt A): 127053, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-34523495

RESUMO

Nickel@MXene quantum dots (Ni@MQDs), as novel flower-like hybrid materials, were firstly prepared through a simple reduction method. The Ni@MQDs exhibited an outstanding catalytic performance for Cr (VI) reduction with a low activation energy (Ea = 18.9 kJ mol-1) and a high kinetic constant (k = 0.4779 min-1) in the presence of formic acid (HCOOH). Density functional theory calculations demonstrated that Ni@MQDs exhibited an upshift of d-band center of active Ni atoms to promote the adsorption of both HCOOH and active H atoms, as well as an improved conductivity to boost the catalytic reaction kinetics, leading to the most favorable catalytic performance. This work may open up a new avenue towards the design and synthesis of novel MQDs-based hybrid catalysts for wastewater treatment.

3.
Sci Total Environ ; 806(Pt 2): 150634, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597565

RESUMO

Numerous epidemiological studies have investigated the lipid interference effects of legacy PFASs, however, no studies on PFAS alternatives and blood lipids have been published. In this study, we explored the association between Cl-PFESAs, a typical PFASs alternative in China, and blood lipid profiles in 1336 Guangzhou community residents using linear and non-linear regression models. The results showed a deleterious effect of Cl-PFESAs and blood lipids: adjusted estimates (ß) for TC, TG, LDL-C and HDL-C per natural log unit increase of 6:2 Cl-PFESA were 0.029 (95% CI: 0.020, 0.038), 0.075 (95% CI: 0.049, 0.101), 0.035 (95% CI: 0.021, 0.049) and -0.071 (95% CI: -0.084, -0.058), respectively. The association between Cl-PFESAs and dyslipidemia was also positively significant (P < 0.05). Furthermore, a non-linear relationship was observed in Cl-PFESAs and serum lipid levels using a restricted cubic splines (RCS) model. In summary, our research suggested a negative impact of Cl-PFESAs on blood lipid patterns and a possible non-linear association.

4.
Anal Chem ; 93(46): 15279-15287, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34748309

RESUMO

Currently, drug-induced liver injury (DILI) has become a huge concern for the majority of modern medicine, whereas the diagnosis of DILI is still in its infancy due to the lack of appropriate methods. Herein, based on the fact that nitric oxide (NO) has been recognized as an early unifying, direct, and vital biomarker for DILI, we rationally designed and developed a NO-responsive ratiometric fluorescent nanoprobe DCNP@MPS@IR NO to quantitatively detect NO and monitor DILI in the second near-infrared (NIR-II) window. In the presence of NO, due to the conversion of IR NO into IR RA and excellent stability of the downconversion nanoparticle (DCNP), DCNP@MPS@IR NO could present a "Turn-On" fluorescence signal at 1050 nm under 808 nm excitation (F1050 Em, 808 Ex) and an "Always-On" fluorescence signal at 1550 nm under 980 nm excitation (F1550 Em, 980 Ex), which led to a "Turn-On" ratiometric fluorescence signal F1050 Em, 808 Ex/F1550 Em, 980 Ex. DCNP@MPS@IR NO was then successfully applied in vitro to selectively detect NO, at a linear concentration range of 0-100 µM with a limit of detection of 0.61 µM. In vivo results revealed that DCNP@MPS@IR was available to quantify NO in acetaminophen (APAP)-induced liver injury, monitor DILI, and screen an antidote for APAP through NIR-II ratiometric fluorescence imaging. We envision that our nanoprobe DCNP@MPS@IR NO might become a really useful biotechnology tool for visualizing and early diagnosis of drug-induced liver injury and revealing the mechanism of drug hepatotoxicity in the clinic in the near future.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nanopartículas , Fluorescência , Corantes Fluorescentes , Humanos , Nanopartículas/toxicidade , Óxido Nítrico
5.
Front Vet Sci ; 8: 736739, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733901

RESUMO

Short-chain fatty acids (SCFAs) are metabolites generated by bacterial fermentation of dietary fiber (DF) in the hindgut. SCFAs are mainly composed of acetate, propionate and butyrate. Many studies have shown that SCFAs play a significant role in the regulation of intestinal health in poultry. SCFAs are primarily absorbed from the intestine and used by enterocytes as a key substrate for energy production. SCFAs can also inhibit the invasion and colonization of pathogens by lowering the intestinal pH. Additionally, butyrate inhibits the expression of nitric oxide synthase (NOS), which encodes inducible nitric oxide synthase (iNOS) in intestinal cells via the PPAR-γ pathway. This pathway causes significant reduction of iNOS and nitrate, and inhibits the proliferation of Enterobacteriaceae to maintain overall intestinal homeostasis. SCFAs can enhance the immune response by stimulating cytokine production (e.g. TNF-α, IL-2, IL-6, and IL-10) in the immune cells of the host. Similarly, it has been established that SCFAs promote the differentiation of T cells into T regulatory cells (Tregs) and expansion by binding to receptors, such as Toll-like receptors (TLR) and G protein-coupled receptors (GPRs), on immune cells. SCFAs have been shown to repair intestinal mucosa and alleviate intestinal inflammation by activating GPRs, inhibiting histone deacetylases (HDACs), and downregulating the expression of pro-inflammatory factor genes. Butyrate improves tight-junction-dependent intestinal barrier function by promoting tight junction (TJ) assembly. In recent years, the demand for banning antibiotics has increased in poultry production. Therefore, it is extremely important to maintain the intestinal health and sustainable production of poultry. Taking nutrition strategies is important to regulate SCFA production by supplementing dietary fiber and prebiotics, SCFA-producing bacteria (SPB), and additives in poultry diet. However, excessive SCFAs will lead to the enteritis in poultry production. There may be an optimal level and proportion of SCFAs in poultry intestine, which benefits to gut health of poultry. This review summarizes the biological functions of SCFAs and their role in gut health, as well as nutritional strategies to regulate SCFA production in the poultry gut.

6.
Nat Prod Bioprospect ; 11(6): 659-670, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34750765

RESUMO

Flavonoid glycoside scutellarin (SCU) has been widely applied in the treatment of cerebral ischemic diseases in China. In this article, we conducted research on the working mechanisms of SCU in hypoxia reoxygenation (HR) injury of isolated cerebral basilar artery (BA) and erebral ischemia reperfusion (CIR) injury in rat models. In isolated rat BA rings, HR causes endothelial dysfunction (ED) and acetylcholine (ACh) induces endothelium-dependent vasodilation. The myography result showed that SCU (100 µM) was able to significantly improve the endothelium-dependent vasodilation induced by Ach. However, SCU did not affect the ACh-induced relaxation in normal BA. Further studies suggested that SCU (10-1000 µM) dose-dependently induced relaxation in isolated BA rings which were significantly blocked by the cGMP dependent protein kinase (PKG) inhibitor Rp-8-Br-cGMPs (PKGI-rp, 4 µM). Pre-incubation with SCU (500 µM) reversed the impairment of endothelium-dependent vasodilation induced by HR, but the reversing effect was blocked if PKGI-rp (4 µM) was added. The brain slice staining test in rats' model of middle cerebral artery occlusion (MCAO) induced CIR proved that the administration of SCU (45, 90 mg/kg, iv) significantly reduced the area of cerebral infarction. The Western blot assay result showed that SCU (45 mg/kg, iv) increased brain PKG activity and PKG protein level after CIR surgery. In conclusion, our findings suggested that SCU possesses the ability of protecting brain cells against CIR injury through vascular endothelium protection and PKG signal.

7.
Neuropsychologia ; 163: 108083, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34742746

RESUMO

During the COVID-19 pandemic, people are at risk of developing disordered eating behaviors. The present study utilized resting-state functional magnetic resonance imaging (fMRI) to examine how trait self-control and its neural mechanisms predict overeating tendencies in young adults during the pandemic. Data on trait self-control, the amplitude of low-frequency fluctuation (ALFF), and resting-state functional connectivity (RSFC) were collected before COVID-19 (September 2019, T1), and data on overeating were collected during COVID-19 (February 2020, T2). Whole-brain regression analyses (N = 538) revealed that higher trait self-control was associated with higher ALFF in the right dorsolateral and ventrolateral prefrontal cortex (DLPFC, VLPFC) and the left anterior insula, and lower ALFF in the left fusiform gyrus and precuneus. With the DLPFC, fusiform gyrus and precuneus as seed regions, trait selfcontrol was associated with decreased connectivity of the orbitofrontal cortex, anterior cingulate cortex, temporal pole, and insula, and increased connectivity between the right VLPFC and anterior cerebellum. Longitudinal mediation models showed that trait self-control (T1) negatively predicted overeating (T2), and the mediating effects of the fusiform gyrus, DLPFC, and VLPFC were moderated by sex. The present study reveals that the brain networks for trait self-control are mainly involved in cognitive and executive control and incentive and emotional processing, demonstrating the longitudinal benefits of trait self-control in alleviating disordered eating behaviors during the pandemic. Sex differences in the neural substrates underlie this association. These finding may have implications of the interventions for behavioral maladjustment.

8.
Front Chem ; 9: 756452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34765586

RESUMO

Eleven new polycyclic polyprenylated acylphloroglucinols (PPAPs, 1-11) and three new monocyclic polyprenylated acylphloroglucinols (MPAPs, 12-14), together with ten known analogues were isolated from the fruits of Garcinia multiflora. These PPAPs belong to three types including the bicyclic polyprenylated acylphloroglucinols (BPAPs), the caged PPAPs, and the complicated PPAPs. Their structures and absolute configurations were determined through HRESIMS, NMR spectroscopy data, electronic circular dichroism (ECD) calculations, and gauge-independent atomic orbital (GIAO) NMR calculations with DP4+ analyses. Moreover, compounds 2 and 7 exhibited moderate cytotoxicity against three human cancer lines (MCF-7, T98, and HepG2) with IC50 values ranging from 9.81 ± 1.56 to 17.00 ± 2.75 µM.

9.
CNS Neurosci Ther ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34767694

RESUMO

AIMS: This study aimed to explore the pathomechanism of a mutation on the leucine-rich glioma inactivated 1 gene (LGI1) identified in a family having autosomal dominant lateral temporal lobe epilepsy (ADLTE), using a precise knock-in mouse model. METHODS AND RESULTS: A novel LGI1 mutation, c.152A>G; p. Asp51Gly, was identified by whole exome sequencing in a Chinese family with ADLTE. The pathomechanism of the mutation was explored by generating Lgi1D51G knock-in mice that precisely phenocopied the epileptic symptoms of human patients. The Lgi1D51G / D51G mice showed spontaneous recurrent generalized seizures and premature death. The Lgi1D51G /+ mice had partial epilepsy, with half of them displaying epileptiform discharges on electroencephalography. They also showed enhanced sensitivity to the convulsant agent pentylenetetrazole. Mechanistically, the secretion of Lgi1 was impaired in the brain of the D51G knock-in mice and the protein level was drastically reduced. Moreover, the antiepileptic drugs, carbamazepine, oxcarbazepine, and sodium valproate, could prolong the survival time of Lgi1D51G / D51G mice, and oxcarbazepine appeared to be the most effective. CONCLUSIONS: We identified a novel epilepsy-causing mutation of LGI1 in humans. The Lgi1D51G /+ mouse model, precisely phenocopying epileptic symptoms of human patients, could be a useful tool in future studies on the pathogenesis and potential therapies for epilepsy.

10.
Acta Neurol Scand ; 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34779509

RESUMO

Microglia are a type of glial cells that play a key role in the repair of damage to the central nervous system (CNS). In the pathological condition of Alzheimer's disease (AD), ß-amyloid peptide and a variety of pro-inflammatory factors can activate microglia, resulting in the secretion of a variety of inflammatory factors and neurotoxins. This leads to neuronal damage and even apoptosis, thus triggering AD. In contrast, microglia can protect the CNS by phagocytizing Aß to slow down AD development. In this review, the roles of microglia in AD neuroinflammation and the scope of immunotherapy for AD are summarized to provide a theoretical basis for AD prevention and treatment.

11.
Perception ; 50(11): 917-932, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34841972

RESUMO

Although previous studies have shown that semantic multisensory integration can be differentially modulated by attention focus, it remains unclear whether attentionally mediated multisensory perceptual facilitation could impact further cognitive performance. Using a delayed matching-to-sample paradigm, the present study investigated the effect of semantically congruent bimodal presentation on subsequent unisensory working memory (WM) performance by manipulating attention focus. The results showed that unisensory WM retrieval was faster in the semantically congruent condition than in the incongruent multisensory encoding condition. However, such a result was only found in the divided-modality attention condition. This result indicates that a robust multisensory representation was constructed during semantically congruent multisensory encoding with divided-modality attention; this representation then accelerated unisensory WM performance, especially auditory WM retrieval. Additionally, an overall faster unisensory WM retrieval was observed under the modality-specific selective attention condition compared with the divided-modality condition, indicating that the division of attention to address two modalities demanded more central executive resources to encode and integrate crossmodal information and to maintain a constructed multisensory representation, leaving few resources for WM retrieval. Additionally, the present finding may support the amodal view that WM has an amodal central storage component that is used to maintain modal-based attention-optimized multisensory representations.


Assuntos
Percepção Auditiva , Memória de Curto Prazo , Estimulação Acústica , Atenção , Humanos , Estimulação Luminosa , Percepção Visual
12.
Environ Int ; 158: 106913, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34624590

RESUMO

BACKGROUND: Epidemiological studies on the associations of legacy per- and polyfluoroalkyl substances (PFASs) and glucose homeostasis remain discordant. Understanding of PFAS alternatives is limited, and few studies have reported joint associations of PFASs and PFAS alternatives. OBJECTIVES: To investigate associations of novel PFAS alternatives (chlorinated perfluoroalkyl ether sulfonic acids, Cl-PFESAs and perfluorobutanoic acid, PFBA) and two legacy PFASs (Perfluorooctanoic acid, PFOA and perfluorooctane sulfonate, PFOS) with glucose-homeostasis markers and explore joint associations of 13 legacy and alternative PFASs with the selected outcomes. METHODS: We used cross-sectional data of 1,038 adults from the Isomers of C8 Health Project in China. Associations of PFASs and PFAS alternatives with glucose-homeostasis were explored in single-pollutant models using generalized linear models with natural cubic splines for PFASs. Bayesian Kernel Machine Regression (BKMR) models were applied to assess joint associations of exposures and outcomes. Sex-specific analyses were also conducted to evaluate effect modification. RESULTS: After adjusting for confounders, both legacy (PFOA, PFOS) and alternative (Cl-PFESAs and PFBA) PFASs were positively associated with glucose-homeostasis markers in single-pollutant models. For example, in the total study population, estimated changes with 95% confidence intervals (CI) of fasting glucose at the 95th percentile of 6:2Cl-PFESA and PFOS against the thresholds were 0.90 (95% CI: 0.59, 1.21) and 0.44 (95% CI: 0.26, 0.62). Positive joint associations were found in BKMR models with 6:2Cl-PFESA contributing most. Sex-specific associations existed in both single- and multi-pollutant models. CONCLUSIONS: Legacy and alternative PFASs were positively associated with glucose-homeostasis markers. 6:2Cl-PFESA was the primary contributor. Sex-specific associations were also identified. These results indicate that joint associations and effect modification should be considered in risk assessment. However, further studies are recommended to strengthen our findings and to elucidate the mechanisms of action of legacy and alternative PFASs.

13.
Anal Chem ; 93(41): 13893-13903, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34609146

RESUMO

NIR-II fluorescent nanoprobes based on inorganic materials, including rare-earth-doped nanoparticles, single-walled carbon nanotubes, CdS quantum dots (QDs), gold nanoclusters, etc., have gained growing interest in bioimaging applications. However, these nanoprobes are usually not biodegradable and lack therapeutic functions. Herein, we developed novel NIR-II fluorescence (FL) imaging and therapeutic nanoprobes based on black phosphorus QDs (BPQDs), which exhibited excellent biodegradability and high tunability of size-dependent optical properties. By adjusting the size of nanoparticles, BPQDs can specifically accumulate in the kidney or liver. Importantly, a low dosage of BPQDs can effectively protect tissues from reactive oxygen species (ROS)-mediated damage in acute kidney and liver injury, which was real-time monitored by responsive NIR-II fluorescence imaging. Overall, we developed novel NIR-II emitting and therapeutic BPQDs with excellent biodegradability vivo, providing a promising candidate for NIR-II FL imaging and ROS scavenging.


Assuntos
Nanotubos de Carbono , Pontos Quânticos , Rim/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imagem Óptica
14.
Bioresour Technol ; 344(Pt A): 126214, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34715336

RESUMO

A major challenge facing by astaxanthin industrialization is the low productivity and high production costs. This study established a two-stage cultivation strategy based on the application of NaCl to improve the production of biomass and astaxanthin by Haematococcus pluvialis. During the first growth stage, 12.5 mg L-1 NaCl led to a remarkable enhancement in biomass, which was 1.28 times compared with the control. Moreover, 2 g L-1 NaCl stimulated the astaxanthin content from 12.18 mg g-1 to 25.92 mg g-1 during the second induction stage. Simultaneously, salinity stress application increased the lipids and GABA contents, as well as the levels of Ca2+ and carotenogenic genes' expression, but suppressed the contents of carbohydrate and protein and high-light induced-ROS. This study proposed a simple and convenient strategy for efficient coproduction of biomass and astaxanthin and provides insights into the underlying mechanism of astaxanthin biosynthesis in H. pluvialis induced by salinity stress.

15.
Se Pu ; 39(9): 941-949, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34486833

RESUMO

Sample pretreatment technology plays a vital role throughout the analysis of complex samples. Sample pretreatment can not only increase the concentration of trace targets in the sample, but also effectively eliminate interference from the sample matrix in instrumental analysis. Adsorbent materials are a key component of sample pretreatment technology. Therefore, the development of efficient and stable new adsorbent materials has acquired significance in research on pretreatment technology. Porous materials are advantageous for use in diverse applications, such as in adsorbents, when they possess controllable nanostructures, a tailored pore surface chemistry, and abundant porosity, and are inexpensive. Particularly in recent years, porous materials derived from metal-organic frameworks (MOFs) feature excellent properties, such as diverse morphology and structure, adjustable pore size, high specific surface area, good thermal stability, and chemical resistance. MOF-derived materials, when used as adsorbents for sample pretreatment, offer the following advantages: (1) The porous materials derived from MOFs typically possess a larger specific surface area than other porous materials. This characteristic is beneficial to improve the extraction capacity and extraction efficiency via an increase in the contact area between the materials and targets; (2) The microscopic porous structure of MOF-derived materials can be easily tuned (by controlling the temperature and time during pyrolysis, gas atmosphere, and heating rate), which is conducive to improve the selectivity of sample pretreatment methods; (3) The metal active sites can be evenly distributed. Owing to the ordered distribution of metal ions in the precursor MOFs and a good periodic framework structure, the metal active sites of the derivatives formed can still maintain a corresponding distance. These metal active sites will not form agglomerates and affect the extraction performance; conversely, other porous materials often require extremely complicated processes to achieve a uniform distribution; (4) Heteroatoms such as nitrogen and sulfur can be easily doped on the framework of MOF-derived porous materials. This doping enables the materials to induce additional interactions such as hydrogen bonding and π-π stacking for adsorbing target analytes. The excellent properties of MOF-derived materials make them promising for use in sample pretreatment. Novel sample pretreatment methods that use MOF-derived materials are constantly being developed. However, the use of MOF-derived materials is limited by the complex preparation process and high production cost of MOF precursors, along with difficulties in mass production. Further, the precise design or functionalization of MOF-derived materials according to the characteristics of targets is a new direction with immense challenges as well as application potential. This review summarizes the application of MOF-derived materials in sample pretreatment methods, including dispersive solid phase extraction (dSPE), magnetic solid phase extraction (MSPE), solid phase microextraction (SPME), stir bar sorptive extraction (SBSE), and dispersive micro solid phase extraction (DMSPE). The preparation methods, functional control, and enrichment efficiencies of various MOF-derived materials are also reviewed. Finally, the application prospects of MOF-derived materials in sample pretreatment are discussed to provide a clear outlook and reference for further related research.


Assuntos
Estruturas Metalorgânicas , Íons , Metais , Extração em Fase Sólida , Microextração em Fase Sólida
16.
Quant Imaging Med Surg ; 11(9): 3978-3989, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34476183

RESUMO

Background: Finding methods to accurately predict the final infarct volumes for acute ischemic stroke patients with full or no recanalization would significantly help to evaluate the potential benefits of thrombolytic therapy. We proposed such a method by constructing a model of ensemble deep learning and machine learning using diffusion-weighted imaging (DWI) only. Methods: The proposed prediction model (named AUNet) combines an adaptive linear ensemble model (ALEM) of machine learning and a deep U-Net network with an accelerated non-local module (U-NL-Net) to learn voxel-wise and spatial features, respectively. Of 40 patients with acute ischemic stroke who received thrombolytic therapy, 17 were fully recanalized, 14 were not recanalized, and nine were partially recanalized. The AUNet was separately trained for full recanalization conditions (AUNetR) and no recanalization (AUNetN) as the best and worst outcomes of thrombolysis, respectively. Results: AUNet performed significantly better in predicting the final infarct volumes in both the recanalization and non-recanalization conditions [area under the receiver operating characteristic curve (AUC) =0.898±0.022, recanalization; AUC =0.875±0.036, non-recanalization: Matthew's correlation coefficient (MCC) =0.863±0.033, recanalization; MCC =0.851±0.025, non-recanalization] than the fixed-thresholding method (AUC =0.776±0.021, P<0.0001, recanalization; AUC =0.692±0.023, P<0.0001, non-recanalization: MCC =0.742±0.035, recanalization; MCC =0.671±0.024, non-recanalization), the logistic regression method (AUC =0.797±0.023, P<0.003, recanalization; AUC =0.751±0.030, P<0.003, non-recanalization: MCC =0.762±0.035, recanalization; MCC =0.730±0.031, non-recanalization), and a recently developed convolutional neural network (AUC =0.814±0.013, P<0.003, recanalization; AUC =0.781±0.027, P<0.003, non-recanalization: MCC =792±0.022, recanalization; MCC =0.758±0.016, non-recanalization). The potential benefit of thrombolysis calculated from AUNetR and AUNetN showed large individual differences (from 12.81% to 239.73%). Conclusions: AUNet improved predictive accuracy over current state-of-the-art methods. More importantly, the accurate prediction of infarct volumes under different recanalization conditions may provide benefitial information for physicians in selecting suitable patients for thrombolytic therapy.

17.
Front Physiol ; 12: 714195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497538

RESUMO

Background: Arterial stiffness assessed by pulse wave velocity is a major risk factor for cardiovascular diseases. The incidence of cardiovascular events remains high in diabetics. However, a clinical prediction model for elevated arterial stiffness using machine learning to identify subjects consequently at higher risk remains to be developed. Methods: Least absolute shrinkage and selection operator and support vector machine-recursive feature elimination were used for feature selection. Four machine learning algorithms were used to construct a prediction model, and their performance was compared based on the area under the receiver operating characteristic curve metric in a discovery dataset (n = 760). The model with the best performance was selected and validated in an independent dataset (n = 912) from the Dryad Digital Repository (https://doi.org/10.5061/dryad.m484p). To apply our model to clinical practice, we built a free and user-friendly web online tool. Results: The predictive model includes the predictors: age, systolic blood pressure, diastolic blood pressure, and body mass index. In the discovery cohort, the gradient boosting-based model outperformed other methods in the elevated arterial stiffness prediction. In the validation cohort, the gradient boosting model showed a good discrimination capacity. A cutoff value of 0.46 for the elevated arterial stiffness risk score in the gradient boosting model resulted in a good specificity (0.813 in the discovery data and 0.761 in the validation data) and sensitivity (0.875 and 0.738, respectively) trade-off points. Conclusion: The gradient boosting-based prediction system presents a good classification in elevated arterial stiffness prediction. The web online tool makes our gradient boosting-based model easily accessible for further clinical studies and utilization.

18.
Front Med (Lausanne) ; 8: 715961, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34532331

RESUMO

Purpose: Radiation pneumonitis (RP) frequently occurs during a treatment course of chest radiotherapy, which significantly reduces the clinical outcome and efficacy of radiotherapy. The ability to easily predict RP before radiotherapy would allow this disease to be avoided. Methods and Materials: This study recruited 48 lung cancer patients requiring chest radiotherapy. For each participant, RNA sequencing (RNA-Seq) was performed on a peripheral blood sample before radiotherapy. The RNA-Seq data was then integrated into a genome-scale flux analysis to develop an RP scoring system for predicting the probability of occurrence of RP. Meanwhile, the clinical information and radiation dosimetric parameters of this cohort were collected for analysis of any statistical associations between these parameters and RP. A non-parametric rank sum test showed no significant difference between the predicted results from the RP score system and the clinically observed occurrence of RP in this cohort. Results: The results of the univariant analysis suggested that the tumor stage, exposure dose, and bilateral lung dose of V5 and V20 were significantly associated with the occurrence of RP. The results of the multivariant analysis suggested that the exposure doses of V5 and V20 were independent risk factors associated with RP and a level of RP ≥ 2, respectively. Thus, our results indicate that our RP scoring system could be applied to accurately predict the risk of RP before radiotherapy because the scores were highly consistent with the clinically observed occurrence of RP. Conclusion: Compared with the standard statistical methods, this genome-scale flux-based scoring system is more accurate, straightforward, and economical, and could therefore be of great significance when making clinical decisions for chest radiotherapy.

19.
Int J Immunopathol Pharmacol ; 35: 20587384211040641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34514899

RESUMO

BACKGROUND: Both C-reactive protein (CRP) level and neutrophil-to-lymphocyte ratio (NLR) are commonly elevated in patients with asthma. It is necessary to develop a novel marker, the combined score of CRP level and NLR (C-NLR score) based on cutoff points of CRP and NLR, and apply it in asthma diagnosis. The aim of this study was to explore whether C-NLR could distinguish children with exacerbated asthma. METHODS: Children suffering from exacerbated asthma were regarded as the asthmatic group (n = 86), which was divided into three groups: mild (n = 54), moderate (n = 17), and severe (n = 15). The control group consisted of children without any allergic disease and infection (n = 38). To compare CRP level and NLR between the asthmatic group and control group, a receiver-operating characteristic curve was constructed to determine area under the curve (AUC) and optimal cutoff point. Thereafter, the C-NLR score was classified as follows: C-NLR score of 2 with an elevated CRP level and high NLR, a C-NLR score of 1 with one of these abnormalities, and a C-NLR score of 0 with a normal CRP level and low NLR. The C-NLR score was then compared among different asthma groups. RESULTS: In the control group, the CRP level and NLR were 1.9 (0.5-2.6) mg/L and 1.01 (0.69-1.31), respectively. In the asthmatic group, the CRP level and NLR were 7.3 (3.2-14.2) mg/L and 3.08 (1.73-5.34), respectively, which were higher than those in the control group (p < 0.001 for CRP and p < 0.001 for NLR). The AUC of CRP was 0.86, and the optimal cutoff point was 3.6 mg/L. The AUC of NLR was 0.86, and the optimal cutoff point was 1.72. The AUC of the C-NLR score was 0.94, and the optimal cutoff point was 1. CONCLUSIONS: C-NLR, a novel inflammatory marker, was applied here for the exacerbated asthma for the first time. Our study has shown C-NLR is a promising marker to distinguish children with exacerbated asthma from healthy children.

20.
Small ; 17(40): e2102363, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34499407

RESUMO

Electrochemical N2 fixation represents a promising strategy toward sustainable NH3 synthesis, whereas the rational design of high-performance catalysts for the nitrogen reduction reaction (NRR) is urgently required but remains challenging. Herein, a novel hexagonal BN quantum dots (BNQDs) decorated Nb2 CTx -MXene (BNQDs@Nb2 CTx ) is explored as an efficient NRR catalyst. BNQDs@Nb2 CTx presents the optimum NRR activity with an NH3 yield rate of 66.3 µg h-1 mg-1 (-0.4 V) and a Faradaic efficiency of 16.7% (-0.3 V), outperforming most of the state-of-the-art NRR catalysts, together with an excellent stability. Theoretical calculations revealed that the synergistic interplay of BNQDs and Nb2 CTx enabled the creation of unique interfacial B sites serving as NRR catalytic centers capable of enhancing the N2 activation, lowering the reaction energy barrier and impeding the H2 evolution.


Assuntos
Pontos Quânticos , Compostos de Boro , Nióbio , Nitrogênio , Tomografia Computadorizada por Raios X
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