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1.
Environ Sci Ecotechnol ; 13: 100208, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36388632

RESUMO

The potential of periodate (PI) in sludge anaerobic digestion is not tapped, although it has recently attracted great research interest in organic contaminants removal and pathogens inactivation in wastewater treatment. This is the first work to demonstrate significant improvement in methane generation from waste activated sludge (WAS) with PI pretreatment and to provide underlying mechanisms. Biochemical methane potential tests indicated that methane yield enhanced from 100.2 to 146.3 L per kg VS (VS, volatile solids) with PI dosages from 0 to 100 mg per g TS (TS, total solids). Electron spin resonance showed PI could be activated without extra activator addition, which might be attributed to the native transition metals (e.g., Fe2+) in WAS, thereby generating hydroxyl radical (•OH), superoxide radicals (•O2 -), and singlet oxygen (1O2). Further scavenging tests demonstrated all of them synergistically promoted WAS disintegration, and their contributions were in the order of •O2 - > •OH > 1O2, leading to the release of substantial biodegradable substances (i.e., proteins and polysaccharides) into the liquid phase for subsequent biotransformation. Moreover, fluorescence and ultraviolet spectroscopy analyses indicated the recalcitrant organics (especially lignocellulose and humus) could be degraded by reducing their aromaticity under oxidative stress of PI, thus readily for methanogenesis. Microbial community analysis revealed some microorganisms participating in hydrolysis, acidogenesis, and acetoclastic methanogenesis were enriched after PI pretreatment. The improved key enzyme activities and up-regulated metabolic pathways further provided direct evidence for enhanced methane production. This research was expected to broaden the application scope of PI and provide more diverse pretreatment choices for energy recovery through anaerobic digestion.

2.
Sci Total Environ ; 857(Pt 2): 159331, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36220480

RESUMO

The influence of ultrasound (US) and potassium permanganate (KMnO4) co-pretreatment on anaerobic digestion of waste activated sludge (WAS) was investigated in this survey. Results showed that KMnO4 (0.3 g/g TSS) cooperated with US (1 W/mL, 15 min) pretreatment significantly increased the cumulative methane yield to 174.44 ± 3.65 mL/g VS compared to the control group (108.72 ± 2.56 mL/g VS), solo US (125.39 ± 2.56 mL/g VS), and solo KMnO4 pretreatment group (160.83 ± 1.61 mL/g VS). Mechanistic investigation revealed that US combined with KMnO4 pretreatment effectively disrupted the structure of extracellular polymeric substances and cell walls by generating reactive radicals, accelerating the release of organics and hydrolytic enzymes as well as improving the biodegradability of soluble organics. Modeling analysis illustrated that the biochemical methane potential and hydrolysis rate of WAS were enhanced under US + KMnO4 pretreatment. Microbial community distribution indicated that the co-pretreatment of US and KMnO4 elevated the total relative abundance of functional microorganisms associated with anaerobic digestion (22.01 %) compared to the control (10.69 %), US alone (12.24 %) and KMnO4 alone (16.20 %).


Assuntos
Permanganato de Potássio , Esgotos , Esgotos/química , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Reatores Biológicos , Metano
3.
Small ; : e2203571, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344457

RESUMO

Multilayered chiral hybrid perovskites are highly desired for highly-sensitive circularly polarized light (CPL) detection rooted in their efficient charge transport and strong chiroptical activity. However, designing multilayered chiral hybrid perovskites remains a huge challenge. Here, through pairing achiral ethylamine (EA)-chiral arylamine in the interlayer space, multilayered chiral alternating cations intercalation-type (ACI) hybrid perovskites (R-/S-PPA) EA2 Pb2 Br7 (PPA = 1-phenylpropylamine) are successfully obtained. Significantly, perovskitizer EA extends the thickness of the quantum well and alternating space cation EA greatly alleviates in-plane tilting distortions of adjacent metal halide octahedra, providing fast channels for in-plane carrier transport. Consequently, single-crystal photodetectors of (R-/S-PPA) EA2 Pb2 Br7 exhibit high circular polarization sensitivity with a large anisotropy factor of 0.3, which falls around the highest value among the layered hybrid perovskites. In addition, a fast responding rate (τr )of 308 µs and a high CPL-detectivity of 8 × 1012 Jones are also presented. This work opens up a new perspective to design multilayered chiral hybrid perovskites for high-sensitive CPL detection.

4.
Antioxidants (Basel) ; 11(11)2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36358536

RESUMO

Liverworts, considered to be the first plant type to successfully make the transition from water to land, can resist different oxidative stress. As characteristic constituents of liverworts, the bibenzyls are efficient antioxidants. In this study, spatial distributions of the bibenzyls within Marchantia polymorpha L., the model species of liverworts, were mapped using airflow-assisted desorption electrospray ionization imaging mass spectrometry. Bibenzyls were found to largely exist in the female receptacle of M. polymorpha, where lunularic acid was found to focus in the central region and bisbibenzyls were enriched in the periphery. The region-specific gene expression and antioxidant activities were characterized. In line with the spatial feature of bibenzyls, higher MpSTCS1A and Mp4CL expression levels and antioxidant ability were exhibited in the archegoniophore. The expression level of MpSTCS1A, and the content of total phenolic acid was increased after UV-B irradiation, suggesting bibenzyls play an important role in UV-B tolerance. Moreover, lunularic acid and extract of archegoniophore at a certain concentration can stimulate the spore germination under normal conditions and UV-B stress. These works broaden our understanding of the significance of bibenzyls in spore propagation and environmental adaptation.

5.
Int J Nanomedicine ; 17: 5187-5205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388876

RESUMO

Background: Mesoporous calcium-silicate nanoparticles (MCSNs) are advanced biomaterials that have been used to control drug delivery for many years. Ultrasmall Prussian blue nanoparticles (UPBNPs) showed high peroxidase and catalase-like activities. This study evaluated the antibacterial and antibiofilm properties, mechanism and cytotoxicity of UPBNPs-MCSNs composites synthesized by both as precursors. Methods: UPBNPs-MCSNs were prepared and characterized. The antibacterial effect of UPBNPs-MCSNs was evaluated by the MTT assay and CFU counting method, and their biosafety was tested by CCK8. Then explore the antibacterial mechanism, including TEM observation of bacterial morphology, and detection of bacterial ROS, LPO and GSH levels. The antibiofilm activity of UPBNPs-MCSNs was tested by E. faecalis biofilm model in human roots. The roots were pretreated with materials and cultured with E. faecalis, and the survival of E. faecalis on the root canal wall was observed by SEM and CLSM. Results: The results showed that UPBNPs-MCSNs had potent antibacterial and antibiofilm activities. They can aggregate on the dentin surface and significantly inhibit E. faecalis adhesion and colonization. Their antibacterial activity is as effective as NaClO and calcium hydroxide (CH), can significantly prolong the time of bacterial colonization than CH, but have lower cytotoxicity to normal cells. We found that UPBNPs-MCSNs trigger a like classic ferroptosis pathway in bacteria. UPBNPs-MCSNs can induce bacteria to produce ROS and LPO, and reduce GSH level. Moreover, we observed that the metal ions chelator and the antioxidant could block their antibacterial activity. Conclusion: These results reveal that UPBNPS-MCSNs have high antibacterial and antibiofilm, and can mediate the bacterial redox pathway ROS/GSH like the classical pathway of ferroptosis, providing a theoretical basis for them to develop into a safe and effective novel root canal disinfectant.


Assuntos
Ferroptose , Nanopartículas , Humanos , Enterococcus faecalis , Cálcio/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Silicatos/farmacologia , Antibacterianos/farmacologia , Oxirredução
6.
Sci Rep ; 12(1): 19779, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396689

RESUMO

The aim of this study was to investigate the prevalence, correlation, and differences of C-shaped root canals (CSRCs) morphology in permanent mandibular premolars and molars in Eastern Chinese individuals using cone-beam computed tomography (CBCT). A total of 8000 mandibular first premolars (MFPs), mandibular second premolars (MSPs), mandibular first molars (MFMs), and mandibular second molars (MSMs) CBCT images from 1000 patients (692 females and 308 males) were collected. The prevalence, correlation, bilateral/unilateral presence, the morphology of CSRCs, level of canal bifurcation, gender differences, and location of radicular grooves (RGs) were evaluated. The prevalence of CSRCs in MFPs, MSPs, MFMs and MSMs were 10.25%, 0.25%, 0.55% and 47.05%, respectively. The prevalence of CSRCs in MFPs of males was higher than that in females, while the prevalence of CSRCs in MSMs of females was higher than that in males (P < 0.05). The bilateral symmetry presence of CSRCs in MSMs was significant but not in MFPs, MSPs, and MFMs. RGs were predominantly found on the mesiolingual (ML) surface of premolars and the lingual surface of molars. There was a high prevalence of CSRCs in MFPs and MSMs in the Eastern Chinese population, but there was no correlation. The prevalence of CSRCs in MFPs and MSMs differ significantly by gender (P < 0.05).


Assuntos
Cavidade Pulpar , Raiz Dentária , Masculino , Feminino , Humanos , Dente Pré-Molar/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Prevalência , Cavidade Pulpar/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , China/epidemiologia
7.
Environ Sci Technol ; 56(22): 16178-16188, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36318116

RESUMO

A novel strategy employing urine wastewater derived from source separation technology, to pretreat waste activated sludge (WAS) for promoting yields of short-chain fatty acids (SCFAs), has been proposed in this study. It was found experimentally that SCFA production could ascend up to 305.4 mg COD/g VSS (volatile suspended solids) with a urine volumetric proportion of 1:2 to the whole reaction system, being 8.8 times that produced in the control. Exploration of the mechanism indicated that WAS disintegration was significantly enhanced due to the synergistic effect of urea and free ammonia (FA). Degradation rates of model organic substrates and measurements of critical enzymatic activities demonstrated that hydrolysis and acidogenesis were inhibited under high urine content (urine proportion of 1:2), while not significantly affected under low urine content (i.e., 1:4), which might be attributed to metal ions existing in urine wastes alleviating the inhibition induced by FA. In contrast, methanogenesis was negatively suppressed by any urine concentration owing to its higher sensitivity to the environmental variations. Shift of microbial population further elucidated the abundance of hydrolytic and acidogenic microbes were enriched in the fermenters with urine addition. The findings provide a new thought for recovering resources from wastes, potentially reducing the pressure of sewage and sludge treatment in wastewater treatment plants.


Assuntos
Ácidos Graxos Voláteis , Esgotos , Esgotos/química , Fermentação , Anaerobiose , Hidrólise , Amônia , Concentração de Íons de Hidrogênio
8.
J Oncol ; 2022: 9998114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36385963

RESUMO

Aim: Since the high cost of reference trastuzumab limits its clinical application, this study aimed to compare the effectiveness and safety of the Zercepac and reference product trastuzumab in neoadjuvant therapy for HER2-positive breast cancer. Methods: This study retrospectively collected clinical data of patients with early-stageHER2-positive breast cancer, who received trastuzumab, pertuzumab, docetaxel, and platinum as neoadjuvant therapy from November 2020 to July 2021. Patients were divided into the Zercepac and reference trastuzumab groups. Reduction in tumor size, clinical response based on RECIST1.1 criteria, pathological complete response (pCR), and adverse events (AEs) were evaluated. Multivariate logistic regression analyses were used to adjust confounders. Results: A total of 105 patients were included in the study, among them, 65 were in the Zercepac group and 40 were in the reference trastuzumab group. The percentage of tumor shrinkage from baseline was comparable between the Zercepac and reference trastuzumab group (47.6 ± 18.6% vs. 43.0 ± 19.9%, p = 0.235). Clinical partial response rate was similar between the two groups (81.5% vs. 70.0%, p = 0.172). There were 28 cases of pCR (70.0%) in the reference trastuzumab group and 46 cases of pCR (70.8%) in the Zercepac group (p = 0.933). The choice of Zercepac or reference trastuzumab was not significantly associated with pCR (OR = 0.96, 95%CI: 0.41-2.28, p = 0.933). Adverse events (AEs) were observed in all patients, and the incidence of ≥3 grade AEs was comparable between the two groups (81.5% vs. 70.0%, p = 0.172). Conclusion: Zercepac has similar effectiveness and safety profile compared with reference trastuzumab in neoadjuvant therapy, which provides treatment options for patients with HER2-positive breast cancer.

9.
Sci Total Environ ; : 160441, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36436650

RESUMO

This work proposed a novel strategy via heat-assisted potassium ferrate (PF) pretreatment to enhance methane production from waste activated sludge (WAS) during anaerobic digestion. In this research, five dosages of PF (i.e., 0, 0.05, 0.1, 0.3 and 0.5 g/g VSS) at two temperatures (i.e., 25 °C and 55 °C) were explored. Biochemical methane potential experiments illustrated that heat-assisted PF pretreatment improved cumulative methane production with the maximum yield up to 163.93 mL CH4/g VSS, 149.0 %, 119.6 % and 121.0 % of that in the control, individual 0.5 g PF/g VSS and individual heat (i.e., 55 °C) pretreatment digesters, respectively. The maximum methane potential (B0) was promoted by 63.2 % with heat-assisted PF pretreatment compared to the control, while the hydrolysis rate (k) changed slightly. Mechanism analysis revealed that heat-assisted PF pretreatment accelerated WAS solubilization and enhanced the biodegradability of released substances, providing more available matrix for bacteria during the following anaerobic digestion processes. Microbial community analysis exhibited that several microbes such as Proteiniclasticum sp., Sedimentibacter sp. and Methanosaeta sp. associated with hydrolysis, acidification and methanogenesis respectively were improved after heat-assisted PF pretreatment. In addition, the relative bioactivities of protease, butyrate kinase and acetate kinase were also increased. Furthermore, variation of dominant genes associated with methane production indicated that acetate-dependent methanogenesis was the main pathway while CO2-dependent methanogenesis pathway was inhibited by heat-assisted PF pretreatment.

10.
Artigo em Inglês | MEDLINE | ID: mdl-36401695

RESUMO

Development of efficient photocatalysts is vital for light-driven removal of refractory antibiotics. Herein, Bi2WO6 microspheres were successfully anchored on the surface of bentonite, and metallic Bi was reduced in-situ by a one-step solvothermal method. Notably, the Bi/Bi2WO6/BT with a mass ratio of 0.15:1:0.1 exhibited the best photocatalytic activity toward degradation of tetracycline (TC) and ciprofloxacin (CIP) after 120 min of visible light irradiation, and their reaction rate constants were 8.0 and 5.5 folds higher than that of pristine Bi2WO6, respectively. The boosted photocatalytic activity over Bi/Bi2WO6/BT was ascribed to the establishment of electrostatic repulsion and SPR effect, which synergistically promoted charges transfer, thus achieving more h+ and ·O2- radical generation. Moreover, possible TC and CIP degradation pathways over Bi/Bi2WO6/BT were proposed based on the identified intermediates, and most of the intermediates were less toxic than TC and CIP. The study provides options to develop high-efficiency photocatalytic composites for contaminants elimination using semiconductors and readily available bentonite.

11.
Fish Shellfish Immunol ; 131: 827-837, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36334698

RESUMO

The objective of the present study was to evaluate the effects of dietary choline levels on growth performance, antioxidant capacity, innate immunity and hemocyte apoptosis of Litopenaeus vannamei. Six isonitrogenous and isolipidic diets were formulated to contain different choline levels: 2.91 (basal diet), 3.85, 4.67, 6.55, 10.70 and 18.90 g kg-1choline, respectively. The results indicated that shrimp fed diet with 4.67 g kg-1 choline had the highest final body weight (FBW), percent weight gain (PWG), specific growth rate (SGR), feed efficiency (FE), and activities of alkaline phosphatase (AKP) and phenoloxidase (PO) in hemolymph among all treatments. Shrimp fed diet with 18.90 g kg-1 choline exhibited significantly lower crude lipid in hepatopancreas than those fed diets with 2.91, 3.85, 4.67 and 6.55 g kg-1 choline (P < 0.05). The concentration of reactive oxygen species (ROS) and apoptosis rate in hemocytes significantly decreased with the increase of dietary choline levels (P < 0.05). Shrimp fed diets with 6.55, 10.70 and 18.90 g kg-1 choline had significantly higher scavenging ability of hydroxyl radical (SAHR) and total antioxidant capacity (T-AOC) in hemolymph than those fed diet with 2.91 g kg-1 choline (P < 0.05). Dietary choline supplementation down-regulated the expression of genes related to apoptosis such as caspase-1, caspase-3, caspase-8, p53, and p38MAPK in hemocytes (P < 0.05), while up-regulated the expression of anti-apoptosis gene bcl2 in hemocytes (P < 0.05). Overall, the results of the present study demonstrated that appropriate dietary choline could improve growth performance and feed utilization, enhance antioxidant capacity and innate immunity, and mitigate apoptosis in Litopenaeus vannamei. Moreover, the inhibition of hemocyte apoptosis by dietary choline may be regulated by the p38MAPK-p53 signaling pathway.

12.
Contrast Media Mol Imaging ; 2022: 5379369, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304778

RESUMO

Amplitude-integrated electroencephalography (aEEG) is an effective and simple means of continuous EEG monitoring beside the neonatal bed, which can be used to predict the early brain injury and prognosis evaluation of neonatal hyperbilirubinemia. This paper summarized 11 randomized controlled studies to meta-analyze the value of aEEG in evaluating neonatal hyperbilirubinemia and acute bilirubin encephalopathy. Through the literature search of health and interest science engineering and computer in the medical databases such as Wanfang Medicine and PubMed database, the medical information literature of aEEG to evaluate the clinical value in neonatal severe hyperbilirubinemia is used, and RevMan 5.2 software is selected for metadecomposition. The experimental results show that their serum total bilirubin is significantly higher than that of normal newborns, and with the aggravation of the condition, the serum expression is higher and higher. aEEG can effectively enhance the detection rate of such sufferers and help sufferers to receive therapy as soon as possible to ensure the prognosis of children.


Assuntos
Encefalopatias , Hiperbilirrubinemia Neonatal , Criança , Recém-Nascido , Humanos , Hiperbilirrubinemia Neonatal/diagnóstico , Eletroencefalografia/métodos
13.
Sci Total Environ ; 858(Pt 1): 159746, 2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36306844

RESUMO

E-waste handling activities release large quantities of polychlorinated biphenyls (PCBs) and halogen flame retardants (HFRs) into the surrounding area, creating a high exposure risk for local residents. However, the possibility of PCBs and HFRs exposure contributing to renal injury has not been extensively studied. To fill this knowledge gap, we conducted an epidemiological analysis of adolescents and adults recruited from an e-waste recycling area and a control area. Some PCBs and HFRs compounds were statistically significantly associated with the levels of ß2-microglobulin (ß2-MG), blood urea nitrogen (BUN), serum creatinine (SCr), and uric acid, with thyroid hormone-related genes found to partly mediate these associations. The interactions of PCBs and HFRs with metals also influenced renal function indexes. Exposure to high concentrations of PCBs and HFRs resulted in higher levels of ß2-MG and lower levels of BUN and SCr in the exposed group. As indicated by the elevated ß2-MG levels, high exposure to PCBs and HFRs may increase the risk of early renal injury for adolescents. These findings help to clarify the impacts of PCBs and HFRs on renal function and highlight the need to protect the health of residents in regions impacted by e-waste handling activities.

14.
Front Psychiatry ; 13: 957685, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36238945

RESUMO

Background: Persistent negative symptoms (PNS) include both primary and secondary negative symptoms that persist after adequate treatment, and represent an unmet therapeutic need. Published magnetic resonance imaging (MRI) evidence of structural and resting-state functional brain abnormalities in schizophrenia with PNS has been inconsistent. Thus, the purpose of this meta-analysis is to identify abnormalities in structural and functional brain regions in patients with PNS compared to healthy controls. Methods: We systematically searched PubMed, Web of Science, and Embase for structural and functional imaging studies based on five research methods, including voxel-based morphometry (VBM), diffusion tensor imaging (DTI), functional connectivity (FC), the amplitude of low-frequency fluctuation or fractional amplitude of low-frequency fluctuation (ALFF/fALFF), and regional homogeneity (ReHo). Afterward, we conducted a coordinate-based meta-analysis by using the activation likelihood estimation algorithm. Results: Twenty-five structural MRI studies and thirty-two functional MRI studies were included in the meta-analyses. Our analysis revealed the presence of structural alterations in patients with PNS in some brain regions including the bilateral insula, medial frontal gyrus, anterior cingulate gyrus, left amygdala, superior temporal gyrus, inferior frontal gyrus, cingulate gyrus and middle temporal gyrus, as well as functional differences in some brain regions including the bilateral precuneus, thalamus, left lentiform nucleus, posterior cingulate gyrus, medial frontal gyrus, and superior frontal gyrus. Conclusion: Our study suggests that structural brain abnormalities are consistently located in the prefrontal, temporal, limbic and subcortical regions, and functional alterations are concentrated in the thalamo-cortical circuits and the default mode network (DMN). This study provides new insights for targeted treatment and intervention to delay further progression of negative symptoms. Systematic review registration: [https://www.crd.york.ac.uk/prospero/], identifier [CRD42022338669].

15.
Int J Mol Sci ; 23(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36232611

RESUMO

Auxenochlorella pyrenoidosa is an efficient photosynthetic microalga with autotrophic growth and reproduction, which has the advantages of rich nutrition and high protein content. Target of rapamycin (TOR) is a conserved protein kinase in eukaryotes both structurally and functionally, but little is known about the TOR signalling in Auxenochlorella pyrenoidosa. Here, we found a conserved ApTOR protein in Auxenochlorella pyrenoidosa, and the key components of TOR complex 1 (TORC1) were present, while the components RICTOR and SIN1 of the TORC2 were absent in Auxenochlorella pyrenoidosa. Drug sensitivity experiments showed that AZD8055 could effectively inhibit the growth of Auxenochlorella pyrenoidosa, whereas rapamycin, Torin1 and KU0063794 had no obvious effect on the growth of Auxenochlorella pyrenoidosaa. Transcriptome data results indicated that Auxenochlorella pyrenoidosa TOR (ApTOR) regulates various intracellular metabolism and signaling pathways in Auxenochlorella pyrenoidosa. Most genes related to chloroplast development and photosynthesis were significantly down-regulated under ApTOR inhibition by AZD8055. In addition, ApTOR was involved in regulating protein synthesis and catabolism by multiple metabolic pathways in Auxenochlorella pyrenoidosa. Importantly, the inhibition of ApTOR by AZD8055 disrupted the normal carbon and nitrogen metabolism, protein and fatty acid metabolism, and TCA cycle of Auxenochlorella pyrenoidosa cells, thus inhibiting the growth of Auxenochlorella pyrenoidosa. These RNA-seq results indicated that ApTOR plays important roles in photosynthesis, intracellular metabolism and cell growth, and provided some insights into the function of ApTOR in Auxenochlorella pyrenoidosa.


Assuntos
Fotossíntese , Sirolimo , Carbono , Ácidos Graxos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Nitrogênio , Proteínas Quinases/metabolismo , Sirolimo/farmacologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-36219657

RESUMO

This article explores the utilization of the effective degree-of-freedom (DoF) of a deep learning model to regularize its stochastic gradient descent (SGD)-based training. The effective DoF of a deep learning model is defined only by a subset of its total parameters. This subset is highly responsive or sensitive toward the training loss, and its cardinality can be used to govern the effective DoF of a model during training. To this aim, the incremental trainable parameter selection (ITPS) algorithm is introduced in this article. The proposed ITPS algorithm acts as a wrapper over SGD and incrementally selects the parameters for updation that exhibit the maximum sensitivity toward the training loss. Hence, it gradually increases the DoF of the model during training. In ideal cases, the proposed algorithm arrives at a model configuration (i.e., DoF) optimum for the task at hand. This whole process results in a regularization-like behavior induced by a gradual increment of the DoF. Since the selection and updation of parameters is a function of the training loss, the proposed algorithm can be seen as a task and data-dependent regularization mechanism. This article exhibits the general utility of ITPS by evaluating it on various prominent neural network architectures such as CNNs, transformers, recurrent neural networks (RNNs), and multilayer perceptrons. These models are trained for image classification and healthcare tasks using the publicly available CIFAR-10, SLT-10, and MIMIC-III datasets.

17.
Microb Cell Fact ; 21(1): 210, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36242071

RESUMO

BACKGROUND: Flavonoid C-glycosides have many beneficial effects and are widely used in food and medicine. However, plants contain a limited number of flavonoid C-glycosides, and it is challenging to create these substances chemically. RESULTS: To screen more robust C-glycosyltransferases (CGTs) for the biosynthesis of flavonoid C-glycosides, one CGT enzyme from Stenoloma chusanum (ScCGT1) was characterized. Biochemical analyses revealed that ScCGT1 showed the C-glycosylation activity for phloretin, 2-hydroxynaringenin, and 2-hydroxyeriodictyol. Structure modeling and mutagenesis experiments indicated that the glycosylation of ScCGT1 may be initiated by the synergistic action of conserved residue His26 and Asp14. The P164T mutation increased C-glycosylation activity by forming a hydrogen bond with the sugar donor. Furthermore, when using phloretin as a substrate, the extracellular nothofagin production obtained from the Escherichia coli strain ScCGT1-P164T reached 38 mg/L, which was 2.3-fold higher than that of the wild-type strain. Finally, it is proved that the coupling catalysis of CjFNS I/F2H and ScCGT1-P164T could convert naringenin into vitexin and isovitexin. CONCLUSION: This is the first time that C-glycosyltransferase has been characterized from fern species and provides a candidate gene and strategy for the efficient production of bioactive C-glycosides using enzyme catalysis and metabolic engineering.


Assuntos
Gleiquênias , Glicosiltransferases , Escherichia coli/metabolismo , Gleiquênias/metabolismo , Flavonoides/metabolismo , Glicosídeos , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Floretina , Açúcares
18.
Front Pediatr ; 10: 936813, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36245747

RESUMO

Background: This study aims to investigate the prevalence estimate of diabetes mellitus (DM) among people with attention deficit hyperactivity disorder (ADHD) as well as the prevalence of ADHD among those with DM. In addition, the impact of ADHD on glycemic control in patients with DM was also assessed using a systematic review and meta-analysis of currently available published data. Materials and methods: The PubMed, Embase, Web of Science, and PsycInfo databases were searched for potential studies. Two reviewers independently selected studies according to the inclusion and exclusion criteria. All pooled analyses were conducted using the random-effects models on Review Manager 5.3. Results: Seventeen observational studies were included. The pooled results showed an increase in the prevalence of DM among patients with ADHD versus those without ADHD [type 1 DM OR: 1.37 (95% CI: 1.17-1.61); type 2 DM OR: 2.05 (95% CI: 1.37-3.07)]. There was an overall 35% increase in the prevalence of ADHD among patients with type 1 DM [OR: 1.35 (95% CI: 1.08-1.73)]. Children with type 1 DM and ADHD had higher levels of hemoglobin A1c [standardized mean of differences: 0.67 (95% CI: 0.48-0.86)], and prevalence of hypoglycemic and ketoacidosis index compared with those without ADHD. Conclusion: Our study revealed the bidirectional associations between ADHD and DM. Patients with ADHD and type 1 DM comorbidities were more likely to have poorer diabetes control. More studies are needed to confirm this association and elucidate the underlying mechanism.

19.
IEEE Trans Biomed Eng ; PP2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269901

RESUMO

Tetanus is a life-threatening infectious disease, which is still common in low- and middle-income countries, including in Vietnam. This disease is characterized by muscle spasm and in severe cases is complicated by autonomic dysfunction. Ideally continuous vital sign monitoring using bedside monitors allows the prompt detection of the onset of autonomic nervous system dysfunction or avoiding rapid deterioration. Detection can be improved using heart rate variability analysis from ECG signals. Recently, characteristic ECG and heart rate variability features have been shown to be of value in classifying tetanus severity. However, conventional manual analysis of ECG is time-consuming. The traditional convolutional neural network (CNN) has limitations in extracting the global context information, due to its fixed-sized kernel filters. In this work, we propose a novel hybrid CNN-Transformer model to automatically classify tetanus severity using tetanus monitoring from low-cost wearable sensors. This model can capture the local features from the CNN and the global features from the Transformer. The time series imaging - spectrogram - is transformed from one-dimensional ECG signal and input to the proposed model. The CNN-Transformer model outperforms state-of-the-art methods in tetanus classification, achieves results with a F1 score of 0.82±0.03, precision of 0.94±0.03, recall of 0.73±0.07, specificity of 0.97±0.02, accuracy of 0.88±0.01 and AUC of 0.85±0.03. In addition, we found that Random Forest with enough manually selected features can be comparable with the proposed CNN-Transformer model.

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