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1.
Plant Cell ; 34(11): 4329-4347, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35916734

RESUMO

The mechanisms underlying leafy heads in vegetables are poorly understood. Here, we cloned a quantitative trait locus (QTL) controlling leafy heads in lettuce (Lactuca sativa). The QTL encodes a transcription factor, SAWTOOTH 1 (LsSAW1), which has a BEL1-like homeodomain and is a homolog of Arabidopsis thaliana. A 1-bp deletion in Lssaw1 contributes to the development of leafy heads. Laser-capture microdissection and RNA-sequencing showed that LsSAW1 regulates leaf dorsiventrality and loss-of-function of Lssaw1 downregulates the expression of many adaxial genes but upregulates abaxial genes. LsSAW1 binds to the promoter region of the adaxial gene ASYMMETRIC LEAVES 1 (LsAS1) to upregulate its expression. Overexpression of LsAS1 compromised the effects of Lssaw1 on heading. LsSAW1 also binds to the promoter region of the abaxial gene YABBY 1 (LsYAB1), but downregulates its expression. Overexpression of LsYAB1 led to bending leaves in LsSAW1 genotypes. LsSAW1 directly interacts with KNOTTED 1 (LsKN1), which is necessary for leafy heads in lettuce. RNA-seq data showed that LsSAW1 and LsKN1 exert antagonistic effects on the expression of thousands of genes. LsSAW1 compromises the ability of LsKN1 to repress LsAS1. Our results suggest that downregulation or loss-of-function of adaxial genes and upregulation of abaxial genes allow for the development of leafy heads.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Lactuca/genética , Lactuca/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Folhas de Planta/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas/genética
2.
BMC Med Inform Decis Mak ; 24(1): 35, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310256

RESUMO

OBJECTIVE: Acute kidney injury (AKI) is a clinical syndrome that occurs as a result of a dramatic decline in kidney function caused by a variety of etiological factors. Its main biomarkers, serum creatinine and urine output, are not effective in diagnosing early AKI. For this reason, this study provides insight into this syndrome by exploring the comorbidities of AKI, which may facilitate the early diagnosis of AKI. In addition, organ crosstalk in AKI was systematically explored based on comorbidities to obtain clinically reliable results. METHODS: We collected data from the Medical Information Mart for Intensive Care-IV database on patients aged [Formula: see text] 18 years in intensive care units (ICU) who were diagnosed with AKI using the criteria proposed by Kidney Disease: Improving Global Outcomes. The Apriori algorithm was used to mine association rules on the diagnoses of 55,486 AKI and non-AKI patients in the ICU. The comorbidities of AKI mined were validated through the Electronic Intensive Care Unit database, the Colombian Open Health Database, and medical literature, after which comorbidity results were visualized using a disease network. Finally, organ diseases were identified and classified from comorbidities to investigate renal crosstalk with other distant organs in AKI. RESULTS: We found 579 AKI comorbidities, and the main ones were disorders of lipoprotein metabolism, essential hypertension, and disorders of fluid, electrolyte, and acid-base balance. Of the 579 comorbidities, 554 were verifiable and 25 were new and not previously reported. In addition, crosstalk between the kidneys and distant non-renal organs including the liver, heart, brain, lungs, and gut was observed in AKI with the strongest heart-kidney crosstalk, followed by lung-kidney crosstalk. CONCLUSION: The comorbidities mined in this study using association rules are scientific and may be used for the early diagnosis of AKI and the construction of AKI predictive models. Furthermore, the organ crosstalk results obtained through comorbidities may provide supporting information for the management of short- and long-term treatment practices for organ dysfunction.


Assuntos
Injúria Renal Aguda , Classificação Internacional de Doenças , Humanos , Idoso , Estudos Prospectivos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Comorbidade , Biomarcadores , Unidades de Terapia Intensiva
3.
Int J Mol Sci ; 25(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39000498

RESUMO

Short chain fatty acids (SCFAs), mainly including acetate, propionate and butyrate, are produced by intestinal bacteria during the fermentation of partially digested and indigestible polysaccharides. SCFAs play an important role in regulating intestinal energy metabolism and maintaining the homeostasis of the intestinal environment and also play an important regulatory role in organs and tissues outside the gut. In recent years, many studies have shown that SCFAs can regulate inflammation and affect host health, and two main signaling mechanisms have also been identified: the activation of G-protein coupled receptors (GPCRs) and inhibition of histone deacetylase (HDAC). In addition, a growing body of evidence highlights the importance of every SCFA in influencing health maintenance and disease development. In this review, we summarized the recent advances concerning the biological properties of SCFAs and their signaling pathways in inflammation and body health. Hopefully, it can provide a systematic theoretical basis for the nutritional prevention and treatment of human diseases.


Assuntos
Ácidos Graxos Voláteis , Inflamação , Humanos , Ácidos Graxos Voláteis/metabolismo , Inflamação/metabolismo , Animais , Transdução de Sinais , Microbioma Gastrointestinal , Receptores Acoplados a Proteínas G/metabolismo , Metabolismo Energético
4.
Int J Mol Sci ; 25(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203794

RESUMO

Stabilization of a G-quadruplex (G4) in the promotor of the c-MYC proto-oncogene leads to inhibition of gene expression, and it thus represents a potentially attractive new strategy for cancer treatment. However, most G4 stabilizers show little selectivity among the many G4s present in the cellular complement of DNA and RNA. Intriguingly, a crescent-shaped cell-penetrating thiazole peptide, TH3, preferentially stabilizes the c-MYC G4 over other promotor G4s, but the mechanisms leading to this selective binding remain obscure. To investigate these mechanisms at the atomic level, we performed an in silico comparative investigation of the binding of TH3 and its analogue TH1 to the G4s from the promotors of c-MYC, c-KIT1, c-KIT2, and BCL2. Molecular docking and molecular dynamics simulations, combined with in-depth analyses of non-covalent interactions and bulk and per-nucleotide binding free energies, revealed that both TH3 and TH1 can induce the formation of a sandwich-like framework through stacking with both the top and bottom G-tetrads of the c-MYC G4 and the adjacent terminal capping nucleotides. This framework produces enhanced binding affinities for c-MYC G4 relative to other promotor G4s, with TH3 exhibiting an outstanding binding priority. Van der Waals interactions were identified to be the key factor in complex formation in all cases. Collectively, our findings fully agree with available experimental data. Therefore, the identified mechanisms leading to specific binding of TH3 towards c-MYC G4 provide valuable information to guide the development of new selective G4 stabilizers.


Assuntos
Genes myc , Simulação de Acoplamento Molecular , Peptídeos/farmacologia , Tiazóis/farmacologia
5.
Small ; 19(21): e2300386, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36823446

RESUMO

Stretchable microsupercapacitors represent emerging miniaturized energy-storage devices for next-generation deformable electronics. Two-dimensional (2D) transition metal carbides (MXenes) are considered attractive electrode materials due to their metallic conductivity, hydrophilic surfaces, and excellent processability. Here, an ultrastretchable microsupercapacitor of interdigitated MXene microelectrodes with crumpled surface textures is created. The microsupercapacitor shows a series of attractive properties including a high specific capacitance of ≈185 mF cm-2 , ultrahigh stretchability up to 800% area strain, and ≈89.7% retention of the initial capacitance after 1000 stretch-relaxation cycles. In addition to static strains, the microsupercapacitor demonstrates robust mechanical properties to retain stable charging-discharging capability under dynamic stretching at different strain rates. A self-powering circuit system utilizes four microsupercapacitor packs to power a light-emitting diode (LED) array, which exhibits stable operations under large tensile strain and skin-attached wearable settings. The developments offer a generic design strategy to enhance the deformability of microsupercapacitors based on 2D nanomaterials.

6.
Plant Biotechnol J ; 21(11): 2307-2321, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37626478

RESUMO

Petal senescence is the final stage of flower development. Transcriptional regulation plays key roles in this process. However, whether and how post-transcriptional regulation involved is still largely unknown. Here, we identified an ethylene-induced NAC family transcription factor DcNAP in carnation (Dianthus caryophyllus L.). One allele, DcNAP-dTdic1, has an insertion of a dTdic1 transposon in its second exon. The dTdic1 transposon disrupts the structure of DcNAP and causes alternative splicing, which transcribes multiple domain-deleted variants (DcNAP2 and others). Conversely, the wild type allele DcNAP transcribes DcNAP1 encoding an intact NAC domain. Silencing DcNAP1 delays and overexpressing DcNAP1 accelerates petal senescence in carnation, while silencing and overexpressing DcNAP2 have the opposite effects, respectively. Further, DcNAP2 could interact with DcNAP1 and interfere the binding and activation activity of DcNAP1 to the promoters of its downstream target ethylene biosynthesis genes DcACS1 and DcACO1. Lastly, ethylene signalling core transcriptional factor DcEIL3-1 can activate the expression of DcNAP1 and DcNAP2 in the same way by binding their promoters. In summary, we discovered a novel mechanism by which DcNAP regulates carnation petal senescence at the post-transcriptional level. It may also provide a useful strategy to manipulate the NAC domains of NAC transcription factors for crop genetic improvement.


Assuntos
Dianthus , Syzygium , Dianthus/genética , Syzygium/metabolismo , Flores , Etilenos/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Plant Biotechnol J ; 21(6): 1229-1239, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36794449

RESUMO

Wheat fixes CO2 by photosynthesis into kernels to nourish humankind. Improving the photosynthesis rate is a major driving force in assimilating atmospheric CO2 and guaranteeing food supply for human beings. Strategies for achieving the above goal need to be improved. Here, we report the cloning and mechanism of CO2 ASSIMILATION RATE AND KERNEL-ENHANCED 1 (CAKE1) from durum wheat (Triticum turgidum L. var. durum). The cake1 mutant displayed a lower photosynthesis rate with smaller grains. Genetic studies identified CAKE1 as HSP90.2-B, encoding cytosolic molecular chaperone folding nascent preproteins. The disturbance of HSP90.2 decreased leaf photosynthesis rate, kernel weight (KW) and yield. Nevertheless, HSP90.2 over-expression increased KW. HSP90.2 recruited and was essential for the chloroplast localization of nuclear-encoded photosynthesis units, for example PsbO. Actin microfilaments docked on the chloroplast surface interacted with HSP90.2 as a subcellular track towards chloroplasts. A natural variation in the hexaploid wheat HSP90.2-B promoter increased its transcription activity, enhanced photosynthesis rate and improved KW and yield. Our study illustrated an HSP90.2-Actin complex sorting client preproteins towards chloroplasts to promote CO2 assimilation and crop production. The beneficial haplotype of Hsp90.2 is rare in modern varieties and could be an excellent molecular switch promoting photosynthesis rate to increase yield in future elite wheat varieties.


Assuntos
Dióxido de Carbono , Triticum , Humanos , Triticum/genética , Fotossíntese/genética , Folhas de Planta , Grão Comestível
8.
Plant Cell Environ ; 46(6): 1935-1945, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36890722

RESUMO

Wheat (Triticum aestivum L.) is a critical food crop feeding the world, but pathogens threaten its production. Wheat Heat Shock Protein 90.2 (HSP90.2) is a pathogen-inducible molecular chaperone folding nascent preproteins. Here, we used wheat HSP90.2 to isolate clients regulated at the posttranslational level. Tetraploid wheat hsp90.2 knockout mutant was susceptible to powdery mildew, while the HSP90.2 overexpression line was resistant, suggesting that HSP90.2 was essential for wheat resistance against powdery mildew. We next isolated 1500 clients of HSP90.2, which contained a wide variety of clients with different biological classifications. We utilized 2Q2, a nucleotide-binding leucine repeat-rich protein, as a model to investigate the potential of HSP90.2 interactome in fungal resistance. The transgenic line co-suppressing 2Q2 was more susceptible to powdery mildew, suggesting 2Q2 as a novel Pm-resistant gene. The 2Q2 protein resided in chloroplasts, and HSP90.2 played a critical role in the accumulation of 2Q2 in thylakoids. Our data provided over 1500 HSP90.2 clients with a potential regulation at the protein folding process and contributed a nontypical approach to isolate pathogenesis-related proteins.


Assuntos
Ascomicetos , Triticum , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ascomicetos/fisiologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia
9.
Arch Virol ; 168(12): 288, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37947926

RESUMO

Nosocomial infections with the opportunistic bacterium Acinetobacter baumannii pose a severe challenge to clinical treatment, which is aggravated by the increasing occurrence of multi-drug resistance, especially resistance to carbapenems. The use of phage therapy as an alternative and supplement to the current antibiotics has become an important research topic in the post-antibiotic era. This review summarizes in vivo and in vitro studies on phage therapy against multi-drug-resistant A. baumannii infection that have used different approaches, including treatment with a single phage, combination with other phages or non-phage agents, and administration of phage-derived enzymes. We also briefly discuss the current challenges of phage-based therapy as well as promising approaches for the treatment of A. baumannii infection in the future.


Assuntos
Acinetobacter baumannii , Bacteriófagos , Bacteriófagos/genética , Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico
10.
Eur J Appl Physiol ; 123(11): 2461-2471, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37294516

RESUMO

PURPOSE: Excessive intensity exercises can bring irreversible damage to the heart. We explore whether heart sounds can evaluate cardiac function after high-intensity exercise and hope to prevent overtraining through the changes of heart sound in future training. METHODS: The study population consisted of 25 male athletes and 24 female athletes. All subjects were healthy and had no history of cardiovascular disease or family history of cardiovascular disease. The subjects were required to do high-intensity exercise for 3 days, with their blood sample and heart sound (HS) signals being collected and analysed before and after exercise. We then developed a Kernel extreme learning machine (KELM) model that can distinguish the state of heart by using the pre- and post-exercise data. RESULTS: There was no significant change in serum cardiac troponin I after 3 days of load cross-country running, which indicates that there was no myocardial injury after the race. The statistical analysis of time-domain characteristics and multi-fractal characteristic parameters of HS showed that the cardiac reserve capacity of the subjects was enhanced after the cross-country running, and the KELM is an effective classifier to recognize HS and the state of the heart after exercise. CONCLUSION: Through the results, we can draw the conclusion that this intensity of exercise will not cause profound damage to the athlete's heart. The findings of this study are of great significance for evaluating the condition of the heart with the proposed index of heart sound and prevention of excessive training that causes damage to the heart.


Assuntos
Ruídos Cardíacos , Corrida , Humanos , Masculino , Feminino , Troponina I , Coração , Exercício Físico , Biomarcadores
11.
Chembiochem ; 23(17): e202200171, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35695820

RESUMO

The carbon backbone of biotin is constructed from the C7 di-acid pimelate, which is converted to an acyl-CoA thioester by an ATP-dependent, pimeloyl-CoA synthetase (PCAS, encoded by BioW). The acyl-thioester is condensed with ʟ-alanine in a decarboxylative, Claisen-like reaction to form an aminoketone (8-amino-7-oxononanoic acid, AON). This step is catalysed by the pyridoxal 5'-phosphate (PLP)-dependent enzyme (AON synthase, AONS, encoded by BioF). Distinct versions of Bacillus subtilis BioW (BsBioW) and E. coli BioF (EcBioF) display strict substrate specificity. In contrast, a BioW-BioF fusion from Corynebacterium amycolatum (CaBioWF) accepts a wider range of mono- and di-fatty acids. Analysis of the active site of the BsBioW : pimeloyl-adenylate complex suggested a key role for a Phe (F192) residue in the CaBioW domain; a F192Y mutant restored the substrate specificity to pimelate. This surprising substrate flexibility also extends to the CaBioF domain, which accepts ʟ-alanine, ʟ-serine and glycine. Structural models of the CaBioWF fusion provide insight into how both domains interact with each other and suggest the presence of an intra-domain tunnel. The CaBioWF fusion catalyses conversion of various fatty acids and amino acids to a range of AON derivatives. Such unexpected, natural broad substrate scope suggests that the CaBioWF fusion is a versatile biocatalyst that can be used to prepare a number of aminoketone analogues.


Assuntos
Proteínas de Bactérias , Biotina , Coenzima A Ligases , Acil Coenzima A/metabolismo , Alanina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biotina/biossíntese , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Escherichia coli/metabolismo , Ácidos Graxos/metabolismo , Fosfato de Piridoxal/metabolismo , Especificidade por Substrato
12.
Plant Biotechnol J ; 20(9): 1756-1769, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35634731

RESUMO

Leaf shape represents a vital agronomic trait for leafy vegetables such as lettuce. Some lettuce cultivars produce lobed leaves, varying from pinnately to palmately lobed, but the genetic mechanisms remain unclear. In this study, we cloned one major quantitative trait locus (QTL) controlling palmately lobed leaves. The candidate gene, LsKN1, encodes a homeobox transcription factor, and has been shown previously to be critical for the development of leafy heads in lettuce. The LsKN1 allele that is upregulated by the insertion of a transposon promotes the development of palmately lobed leaves. We demonstrated that LsKN1 upregulated LsCUC2 and LsCUC3 through different mechanisms, and their upregulation was critical for the development of palmately lobed leaves. LsKN1 binds the promoter of LsPID to promote auxin biosynthesis, which positively contributes to the development of palmately lobed leaves. In contrast, LsKN1 suppresses GA biosynthesis to promote palmately lobed leaves. LsKN1 also binds to the promoter of LsAS1, a dorsiventrality gene, to downregulate its expression. Overexpression of the LsAS1 gene compromised the effects of the LsKN1 gene changing palmately to pinnately lobed leaves. Our study illustrated that the upregulated LsKN1 gene led to palmately lobed leaves in lettuce by integrating several downstream pathways, including auxin, gibberellin, and leaf dorsiventrality pathways.


Assuntos
Ácidos Indolacéticos , Lactuca , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Lactuca/genética , Folhas de Planta/metabolismo , Locos de Características Quantitativas
13.
Cancer Cell Int ; 22(1): 188, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568883

RESUMO

BACKGROUND: Anillin (ANLN) is an actin-binding protein that is essential for cell division and contributes to cell growth and migration. Although previous studies have shown that ANLN is related to carcinogenesis, no pan-cancer analyses of ANLN have been reported. Accordingly, in this study, we evaluated the carcinogenic roles of ANLN in various cancer types using online databases. METHODS: We evaluated the potential carcinogenic roles of ANLN using TIMER2 and Gene Expression Omnibus databases with 33 types of cancers. We further investigated the associations of ANLN with patient prognosis, genetic alterations, phosphorylation levels, and immune infiltration in multiple cancers using GEPIA2, cBioPortal, UACLAN, and TIMER2 databases. Additionally, the potential functions of ANLN were explored using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses. Reverse transcription quantitative polymerase chain reaction and immunohistochemistry were used to determine ANLN mRNA and protein expression in colorectal cancer (CRC), gastric cancer (GC), and hepatocellular carcinoma (HCC) cell lines. RESULTS: ANLN was overexpressed in various tumor tissues compared with corresponding normal tissues, and significant correlations between ANLN expression and patient prognosis, genetic alterations, phosphorylation levels, and immune infiltration were noted. Moreover, enrichment analysis suggested that ANLN functionally affected endocytosis, regulation of actin cytoskeleton, and oxytocin signaling pathways. Importantly, ANLN mRNA and protein expression levels were upregulated in gastrointestinal cancers, including CRC, GC, and HCC. CONCLUSIONS: Our findings suggested that ANLN participated in tumorigenesis and cancer progression and may have applications as a promising biomarker of immune infiltration and prognosis in various cancers.

14.
Inorg Chem ; 61(37): 14648-14661, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36073797

RESUMO

Template-directed assembly of giant cluster-based nanomaterials is an everlasting theme in cluster science. In this work, ethylenediamine tetramethylphosphonic acid [H8EDTPA = (POCH2(OH)2)4C2H4N2] and [B-α-SbW9O33]9- were, respectively, used as an organic template and an inorganic template to prepare an organophosphonic acid-regulating PV-SbIII-heteroatom-inserted polyoxotungstate aggregate [H2N(CH3)2]5Na11H9[CeW4O10(HEDTPA)SbW15O50][B-α-SbW9O33]2·36H2O (1). Noteworthily, organophosphonic acid ligand not only works as an organic template leading to the assembly of a [HEDTPASbW15O50]14- building block but also further bridges the sandwich-type [CeW4O10(B-α-SbW9O33)2]11- entity. To extend its potential application in electrochemical sensing properties, we prepared a three-dimensional 1@EGO composite (EGO = reduced graphene oxide functionalized by ethylenediamine) with porous architecture and a prominent conducting ability. Furthermore, the 1@EGO composite was explored as a modification material for glassy carbon electrodes to build a dual-signal readout electrochemical aptasensor for carcinogens, which shows much better detection performance for aflatoxin B1 compared with traditional single-signal biosensors.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Nanopartículas Metálicas , Aflatoxina B1 , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Carcinógenos , Técnicas Eletroquímicas/métodos , Etilenodiaminas , Ouro/química , Grafite/química , Ligantes , Limite de Detecção , Nanopartículas Metálicas/química
15.
Inorg Chem ; 61(43): 17166-17177, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36240053

RESUMO

Rapid development of the synthetic chemistry of polyoxometalates (POMs) has greatly driven the generation of structurally variable innovative POM-based materials. Herein, we synthesized a novel PIII and TeIV synergistically controlling octa-CeIII-encapsulated heteropolyoxotungstate [H2N(CH3)2]11K2Na6H11[Ce8(CH3COO)2(HPIIIO3)2W8O20(H2O)12(B-ß-TeW8O30)2(B-α-TeW8O31)4]·64H2O (1). Its distinctive anion skeleton [Ce8(CH3COO)2(HPIIIO3)2W8O20(H2O)12(B-ß-TeW8O30)2(B-α-TeW8O31)4]30- is built by two tetra-vacancy [B-ß-TeW8O30]8- and four tetra-vacancy [B-α-TeW8O31]10- moieties linked through an inorganic-organic hybrid [Ce8(CH3COO)2(HPIIIO3)2W8O20(H2O)12]26+ {Ce8P2W8} cluster core. Interestingly, {Ce8P2W8} is assembled from four [W2O11]10- groups and two [HPIIIO3]2- anions and eight Ce3+ ions. Besides, 1 was further composited with carboxylated multiwalled carbon nanotube (CMCN), resulting in a bi-component 1/CMCN nanocomposite. An electrochemical recognition platform (named as 1/CMCN/GCE) was built by modifying 1/CMCN on a glassy carbon electrode (GCE) for electrochemical detection of dopamine (DPA) at physiological pH (pH = 7.0). The findings have shown that 1/CMCN/GCE exhibits a good detection limit of 4.95 nM for DPA. This work provides considerable inspiration to promote innovative and rational structure designs of POM-based materials and expand their applications to electrochemical and biological detection fields.


Assuntos
Técnicas Eletroquímicas , Nanotubos de Carbono , Técnicas Eletroquímicas/métodos , Limite de Detecção , Eletrodos , Nanotubos de Carbono/química , Dopamina
16.
Neuroradiology ; 64(7): 1373-1382, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35037985

RESUMO

PURPOSE: This study aimed to investigate the clinical usefulness of the enhanced-T1WI-based deep learning radiomics model (DLRM) in differentiating low- and high-grade meningiomas. METHODS: A total of 132 patients with pathologically confirmed meningiomas were consecutively enrolled (105 in the training cohort and 27 in the test cohort). Radiomics features and deep learning features were extracted from T1 weighted images (T1WI) (both axial and sagittal) and the maximum slice of the axial tumor lesion, respectively. Then, the synthetic minority oversampling technique (SMOTE) was utilized to balance the sample numbers. The optimal discriminative features were selected for model building. LightGBM algorithm was used to develop DLRM by a combination of radiomics features and deep learning features. For comparison, a radiomics model (RM) and a deep learning model (DLM) were constructed using a similar method as well. Differentiating efficacy was determined by using the receiver operating characteristic (ROC) analysis. RESULTS: A total of 15 features were selected to construct the DLRM with SMOTE, which showed good discrimination performance in both the training and test cohorts. The DLRM outperformed RM and DLM for differentiating low- and high-grade meningiomas (training AUC: 0.988 vs. 0.980 vs. 0.892; test AUC: 0.935 vs. 0.918 vs. 0.718). The accuracy, sensitivity, and specificity of the DLRM with SMOTE were 0.926, 0.900, and 0.924 in the test cohort, respectively. CONCLUSION: The DLRM with SMOTE based on enhanced T1WI images has favorable performance for noninvasively individualized prediction of meningioma grades, which exhibited favorable clinical usefulness superior over the radiomics features.


Assuntos
Aprendizado Profundo , Neoplasias Meníngeas , Meningioma , Algoritmos , Estudos de Coortes , Humanos , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico por imagem , Meningioma/patologia , Meningioma/cirurgia , Curva ROC , Estudos Retrospectivos
17.
Nano Lett ; 21(18): 7561-7568, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34494441

RESUMO

In spite of the excellent electrical and electrochemical properties, two-dimensional transition metal carbide (MXene) is often limited by the high stiffness for the direct implementation in next-generation stretchable and wearable energy storage devices. The improved deformability has been achieved in ultrathin composite electrodes utilizing additives that substantially reduce the specific capacitance. Here, we demonstrate an ultrastretchable and high-performing supercapacitor based on MXene electrodes with crumpled textures. After screening on the thickness, the crumpled MXene film of ∼3 µm in thickness is identified as the optimal choice to mitigate the crack formations under large and repetitive mechanical strains. The as-prepared symmetric supercapacitor, therefore, demonstrates a high specific capacitance of ∼470 mF cm-2, ultrahigh stretchability up to 800% area strain, and >90% retention of the initial capacitance after 1000 stretch-relaxation cycles. The developments offer an attractive avenue to design stretchable electrodes based on various two-dimensional nanomaterials and their composites.

18.
Biomed Eng Online ; 20(1): 87, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34461905

RESUMO

BACKGROUND AND OBJECTIVE: Moderate exercise contributes to good health. However, excessive exercise may lead to cardiac fatigue, myocardial damage and even exercise sudden death. Monitoring the heart health has important implication to prevent exercise sudden death. Diagnosis methods such as electrocardiogram, echocardiogram, blood pressure and histological analysis have shown that arrhythmia and left ventricular fibrosis are early warning symptoms of exercise sudden death. Heart sounds (HS) can reflect the changes of cardiac valve, cardiac blood flow and myocardial function. Deep learning has drawn wide attention because of its ability to recognize disease. Therefore, a deep learning method combined with HS was proposed to predict exercise sudden death in New Zealand rabbits. The objective is to develop a method to predict exercise sudden death in New Zealand rabbits. METHODS: This paper proposed a method to predict exercise sudden death in New Zealand rabbits based on convolutional neural network (CNN) and gated recurrent unit (GRU). The weight-bearing exhaustive swimming experiment was conducted to obtain the HS of exercise sudden death and surviving New Zealand rabbits (n = 11/10) at four different time points. Then, the improved Viola integral method and double threshold method were employed to segment HS signals. The segmented HS frames at different time points were taken as the input of a combined CNN and GRU called CNN-GRU network to complete the prediction of exercise sudden death. RESULTS: In order to evaluate the performance of proposed network, CNN and GRU were used for comparison. When the fourth time point segmented HS frames were taken as input, the result shows that the proposed network has better performance with an accuracy of 89.57%, a sensitivity of 89.38% and a specificity of 92.20%. In addition, the segmented HS frames at different time points were input into CNN-GRU network, and the result shows that with the progress of the experiment, the prediction accuracy of exercise sudden death in New Zealand rabbits increased from 50.98 to 89.57%. CONCLUSION: The proposed network shows good performance in classifying HS, which proves the feasibility of deep learning in exploring exercise sudden death. Further, it may have important implications in helping humans explore exercise sudden death.


Assuntos
Ruídos Cardíacos , Natação , Animais , Morte Súbita , Coração , Redes Neurais de Computação , Coelhos
19.
Nat Chem Biol ; 13(6): 660-667, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28414710

RESUMO

Biotin is an essential vitamin in plants and mammals, functioning as the carbon dioxide carrier within central lipid metabolism. Bacterial pimeloyl-CoA synthetase (BioW) acts as a highly specific substrate-selection gate, ensuring the integrity of the carbon chain in biotin synthesis. BioW catalyzes the condensation of pimelic acid (C7 dicarboxylic acid) with CoASH in an ATP-dependent manner to form pimeloyl-CoA, the first dedicated biotin building block. Multiple structures of Bacillus subtilis BioW together capture all three substrates, as well as the intermediate pimeloyl-adenylate and product pyrophosphate (PPi), indicating that the enzyme uses an internal ruler to select the correct dicarboxylic acid substrate. Both the catalytic mechanism and the surprising stability of the adenylate intermediate were rationalized through site-directed mutagenesis. Building on this understanding, BioW was engineered to synthesize high-value heptanoyl (C7) and octanoyl (C8) monocarboxylic acid-CoA and C8 dicarboxylic-CoA products, highlighting the enzyme's synthetic potential.


Assuntos
Monofosfato de Adenosina/metabolismo , Coenzima A Ligases/metabolismo , Ácidos Graxos/biossíntese , Engenharia de Proteínas , Sulfetos/metabolismo , Monofosfato de Adenosina/biossíntese , Monofosfato de Adenosina/química , Bacillus , Domínio Catalítico , Ácidos Graxos/química , Estrutura Molecular , Mutagênese Sítio-Dirigida , Dobramento de Proteína
20.
Langmuir ; 35(50): 16545-16554, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31755726

RESUMO

Covalent organic frameworks (COFs) have attracted broad interest in a number of fields including gas access, catalysis, and ionic adsorption. However, owing to the low stability in water, the application of COFs in the field of oil/water separation is extensively impeded. In this paper, we synthesized COF-DhaTab/polyacrylonitrile (PAN) nanofibrous composite membranes with a bioinspired spindle-knotted structure via a facile blending electrospinning method. The COF-DhaTab/PAN composite membrane shows prewetting-induced superoleophobicity under water and superhydrophobicity under oil. It possesses outstanding rejection ratio (>99.9%), excellent antifouling performance, and ultrahigh oil/water mixture flux up to 4229.29 L/m2h even though driven only by gravity. Specifically, an extraordinary oil contact angle under water (152.3°) and a satisfied water contact angle under oil (153.7°) were offered by the composite membrane. These are mainly attributed to the spindle-knotted structures induced by COFs. To the best of our knowledge, the application of COF/PAN composite membrane in the field of oil/water separation has never been reported. It is an innovative approach for oily wastewater treatment and oil purification.

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