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1.
AJNR Am J Neuroradiol ; 45(4): 504-510, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38453416

RESUMO

BACKGROUND AND PURPOSE: The habenula is a key node in the regulation of emotion-related behavior. Accurate visualization of the habenula and its reliable quantitative analysis is vital for the assessment of psychiatric disorders. To obtain high-contrast habenula images and allow them to be compatible with clinical applications, this preliminary study compared 3T MP2RAGE and quantitative susceptibility mapping with MPRAGE by evaluating the habenula segmentation performance. MATERIALS AND METHODS: Ten healthy volunteers were scanned twice with 3T MPRAGE and MP2RAGE and once with quantitative susceptibility mapping. Image quality and visibility of habenula anatomic features were analyzed by 3 radiologists using a 5-point scale. Contrast assessments of the habenula and thalamus were also performed. The reproducibility of the habenula volume from MPRAGE and MP2RAGE was evaluated by manual segmentation and the Multiple Automatically Generated Template brain segmentation algorithm (MAGeTbrain). T1 values and susceptibility were measured in the whole habenula and habenula geometric subregion using MP2RAGE T1-mapping and quantitative susceptibility mapping. RESULTS: The 3T MP2RAGE and quantitative susceptibility mapping demonstrated clear boundaries and anatomic features of the habenula compared with MPRAGE, with a higher SNR and contrast-to-noise ratio (all P < .05). Additionally, 3T MP2RAGE provided reliable habenula manual and MAGeTbrain segmentation volume estimates with greater reproducibility. T1-mapping derived from MP2RAGE was highly reliable, and susceptibility contrast was highly nonuniform within the habenula. CONCLUSIONS: We identified an optimized sequence combination (3T MP2RAGE combined with quantitative susceptibility mapping) that may be useful for enhancing habenula visualization and yielding more reliable quantitative data.


Assuntos
Habenula , Humanos , Habenula/diagnóstico por imagem , Reprodutibilidade dos Testes , Algoritmos , Imageamento por Ressonância Magnética/métodos , Voluntários Saudáveis , Encéfalo
2.
Front Neurol ; 14: 1273473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965167

RESUMO

Background: Yoga is a non-pharmacological conservative therapeutic modality that can be employed for the management of chronic low back pain (CLBP). In this overview, we have summarized and evaluated data from current systematic reviews (SRs) on the use of yoga for CLBP. Methods: We comprehensively searched SRs on the use of yoga for CLBP in nine electronic databases from inception to September 2023. The methodological quality was evaluated using the Assessment of Multiple Systematic Review Scale-2 (AMSTAR-2). The reporting quality of the included SRs was evaluated using the Preferred Reporting Item for Systematic Review and Meta-Analysis-2020 (PRISMA-2020), and the quality of data was graded using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Two independent researchers performed the screening, data extraction, and quality assessment process of SRs. Results: A total of 13 SRs were included. The results of the AMSTAR-2 indicated that the methodological quality of the included studies was relatively low. The PRISMA-2020 checklist evaluation results indicated that methodological limitations in reporting, especially regarding data processing and presentation, were the main weaknesses. The GRADE assessment indicated that 30 outcomes were rated moderate, 42 were rated low level, and 20 were rated very low level. Downgrading factors were mainly due to the limitations of the included studies. Conclusion: Yoga appears to be an effective and safe non-pharmacological therapeutic modality for the Management of CLBP. Currently, it may exhibit better efficacy in improving pain and functional disability associated with CLBP. However, the methodological quality and quality of evidence for SRs/MAs in the included studies were generally low, and these results should be interpreted cautiously.

3.
J Colloid Interface Sci ; 645: 895-905, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37178566

RESUMO

Developing the robust non-precious metal bifunctional electrocatalyst is highly imperative for the hydrogen evolution from overall water splitting. Herein, a Ni foam (NF)-supported ternary Ni/Mo bimetallic complex (Ni/Mo-TEC@NF), hierarchically constructed by coupling the in-situ formed MoNi4 alloys and Ni2Mo3O8 with Ni3Mo3C on NF, has been developed through a facile method involving the in-situ hydrothermal growth of the Ni-Mo oxides/polydopamine (NiMoOx/PDA) complex on NF and a subsequent annealing in a reduction atmosphere. Synchronously, N and P atoms are co-doped into Ni/Mo-TEC during the annealing procedure using phosphomolybdic acid and PDA raw materials as P and N sources, respectively. The resultant N, P-Ni/Mo-TEC@NF shows outstanding electrocatalytic activities and tremendous stability for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), due to the multiple heterojunction effect-promoted electron transfer, the large number of exposed active sites, and the modulated electronic structure by the N and P co-doping. It only needs a low overpotential of 22 mV to afford the current density of 10 mA·cm-2 for HER in alkaline electrolyte. More importantly, as the anode and cathode, it requires only 1.59 and 1.65 V to achieve 50 and 100 mA·cm-2 for overall water splitting, respectively, comparable to the benchmark Pt/C@NF//RuO2@NF couple. This work could spur the search for economical and efficient electrodes by in situ constructing multiple bimetallic components on 3D conductive substrates for practical hydrogen generation.

4.
Mar Environ Res ; 188: 106002, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37119661

RESUMO

Seagrass beds contributes up to 10% ocean carbon storage. Carbon fixation in seagrass bed greatly affect global carbon cycle. Currently, six carbon fixation pathways are widely studied: Calvin, reductive tricarboxylic acid (rTCA), Wood-Ljungdahl (WL), 3-hydroxypropionate (3HP), 3-hydroxypropionate/4-hydroxybutyrate (3HP/4HB) and dicarboxylate/4-hydroxybutyrate (DC/4-HB). Despite the knowledges about carbon fixation increase, the carbon fixation strategies in seagrass bed sediment remain unexplored. We collected seagrass bed sediment samples from three sites with different characteristics in Weihai, a city in Shandong, China. The carbon fixation strategies were investigated through metagenomics. The results exhibited that five pathways were present, of which Calvin and WL were the most dominant. The community structure of microorganisms containing the key genes of these pathways were further analyzed, and those dominant microorganisms with carbon fixing potential were revealed. Phosphorus significantly negatively corelated with those microorganisms. This study provides an insight into the strategies of carbon fixation in seagrass bed sediments.


Assuntos
Ciclo do Carbono , Hidroxibutiratos , Processos Autotróficos , Carbono , Sedimentos Geológicos
5.
ChemSusChem ; 16(5): e202202019, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36511949

RESUMO

The drastically increasing consumption of petroleum-derived plastics hasserious environmental impacts and raises public concerns. Poly(ethylene terephthalate) (PET) is amongst the most extensively produced synthetic polymers. Enzymatic hydrolysis of PET recently emerged as an enticing path for plastic degradation and recycling. In-lab directed evolution has revealed the great potential of PET hydrolases (PETases). However, the time-consuming and laborious PETase assays hinder the identification of effective variants in large mutant libraries. Herein, we devise and validate a dual fluorescence-based high-throughput screening (HTS) assay for a representative IsPETase. The two-round HTS of a pilot library consisting of 2850 IsPETase variants yields six mutant IsPETases with 1.3-4.9 folds improved activities. Compared to the currently used structure- or computational redesign-based PETase engineering, this HTS approach provides a new strategy for discovery of new beneficial mutation patterns of PETases.


Assuntos
Hidrolases , Polietilenotereftalatos , Hidrolases/metabolismo , Polietilenotereftalatos/metabolismo , Ensaios de Triagem em Larga Escala , Etilenos , Plásticos
6.
Phys Med Biol ; 67(10)2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35453134

RESUMO

Objective.To develop two combined clinical-radiomics models of pericoronary adipose tissue (PCAT) for the presence and characterization of non-calcified plaques on non-contrast CT scan.Approach.Altogether, 431 patients undergoing Coronary Computed Tomography Angiography from March 2019 to June 2021 who had complete data were enrolled, including 173 patients with non-calcified plaques of the right coronary artery(RCA) and 258 with no abnormality. PCAT was segmented around the proximal RCA on non-contrast CT scan (calcium score acquisition). Two best models were established by screening features and classifiers respectively using FeAture Explorer software. Model 1 distinguished normal coronary arteries from those with non-calcified plaques, and model 2 distinguished vulnerable plaques in non-calcified plaques. Performance was assessed by the area under the receiver operating characteristic curve (AUC-ROC).Main results.4 and 9 features were selected for the establishment of the radiomics model respectively through Model 1 and 2. In the test group, the AUC values, sensitivity, specificity and accuracy were 0.833%, 78.3%, 80.8%, 76.6% and 0.7467%, 75.0%, 77.8%, 73.5%, respectively. The combined model including radiomics features and independent clinical factors yielded an AUC, sensitivity, specificity and accuracy of 0.896%, 81.4%, 86.5%, 77.9% for model 1 and 0.752%, 75.0%, 77.8%, 73.5% for model 2.Significance.The combined clinical-radiomics models based on non-contrast CT images of PCAT had good diagnostic efficacy for non-calcified and vulnerable plaques.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Tecido Adiposo/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
7.
Sci Rep ; 11(1): 2879, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33536571

RESUMO

Alzheimer's disease (AD) is a common neurodegenerative disease with poor prognosis. New options for drug discovery targets are needed. We developed an imaging based arrayed CRISPR method to interrogate the human genome for modulation of in vitro correlates of AD features, and used this to assess 1525 human genes related to tau aggregation, autophagy and mitochondria. This work revealed (I) a network of tau aggregation modulators including the NF-κB pathway and inflammatory signaling, (II) a correlation between mitochondrial morphology, respiratory function and transcriptomics, (III) machine learning predicted novel roles of genes and pathways in autophagic processes and (IV) individual gene function inferences and interactions among biological processes via multi-feature clustering. These studies provide a platform to interrogate underexplored aspects of AD biology and offer several specific hypotheses for future drug discovery efforts.


Assuntos
Doença de Alzheimer/genética , Autofagia/genética , Modelos Genéticos , Agregação Patológica de Proteínas/genética , Proteínas tau/metabolismo , Doença de Alzheimer/patologia , Encéfalo/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Engenharia Genética , Humanos , Aprendizado de Máquina , Mitocôndrias/genética , Mitocôndrias/patologia , Neurônios , Agregação Patológica de Proteínas/patologia , Transdução de Sinais/genética
8.
Biosens Bioelectron ; 50: 311-7, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23876542

RESUMO

Proof-in-principle of a new surface-scanning coil detector has been demonstrated. This new coil detector excites and measures the resonant frequency of free-standing magnetoelastic (ME) biosensors that may now be placed outside the coil boundaries. With this coil design, the biosensors are no longer required to be placed inside the coil before frequency measurement. Hence, this new coil enables bacterial pathogens to be detected on fresh food surfaces in real-time and in-situ. The new coil measurement technique was demonstrated using an E2 phage-coated ME biosensor to detect Salmonella typhimurium on tomato surfaces. Real-time, in-situ detection was achieved with a limit of detection (LOD) statistically determined to be lower than 1.5×10(3) CFU/mm(2) with a confidence level of difference higher than 95% (p<0.05).


Assuntos
Técnicas Biossensoriais/instrumentação , Microbiologia de Alimentos/instrumentação , Salmonella typhimurium/isolamento & purificação , Solanum lycopersicum/microbiologia , Contagem de Colônia Microbiana , Desenho de Equipamento , Magnetismo/instrumentação
9.
J Food Prot ; 75(4): 631-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22488049

RESUMO

This article presents rapid, sensitive, direct detection of Salmonella Typhimurium on eggshells by using wireless magnetoelastic (ME) biosensors. The biosensor consists of a freestanding, strip-shaped ME resonator as the signal transducer and the E2 phage as the biomolecular recognition element that selectively binds with Salmonella Typhimurium. This ME biosensor is a type of mass-sensitive biosensor that can be wirelessly actuated into mechanical resonance by an externally applied timevarying magnetic field. When the biosensor binds with Salmonella Typhimurium, the mass of the sensor increases, resulting in a decrease in the sensor's resonant frequency. Multiple E2 phage-coated biosensors (measurement sensors) were placed on eggshells spiked with Salmonella Typhimurium of various concentrations (1.6 to 1.6 × 10(7) CFU/cm(2)). Control sensors without phage were also used to compensate for environmental effects and nonspecific binding. After 20 min in a humidity-controlled chamber (95%) to allow binding of the bacteria to the sensors to occur, the resonant frequency of the sensors was wirelessly measured and compared with their initial resonant frequency. The resonant frequency change of the measurement sensors was found to be statistically different from that of the control sensors down to 1.6 × 10(2) CFU/cm(2), the detection limit for this work. In addition, scanning electron microscopy imaging verified that the measured resonant frequency changes were directly related to the number of bound cells on the sensor surface. The total assay time of the presented methodology was approximately 30 min, facilitating rapid detection of Salmonella Typhimurium without any preceding sampling procedures.


Assuntos
Técnicas Biossensoriais , Casca de Ovo/microbiologia , Contaminação de Alimentos/análise , Salmonella typhimurium/isolamento & purificação , Animais , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/normas , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Humanos , Intoxicação Alimentar por Salmonella/prevenção & controle , Sensibilidade e Especificidade
10.
Biosens Bioelectron ; 26(5): 2361-7, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21084182

RESUMO

One of the important applications for which phage-immobilized magnetoelastic (ME) biosensors are being developed is the wireless, on-site detection of pathogenic bacteria for food safety and bio-security. Until now, such biosensors have been constructed by immobilizing a landscape phage probe on gold-coated ME resonators via physical adsorption. Although the physical adsorption method is simple, the immobilization stability and surface coverage of phage probes on differently functionalized sensor surfaces need to be evaluated as a potential way to enhance the detection capabilities of the biosensors. As a model study, a filamentous fd-tet phage that specifically binds streptavidin was adsorbed on either bare or surface-functionalized gold-coated ME resonators. The surface functionalization was performed through the formation of three self-assembled monolayers with a different terminator, based on the sulfur-gold chemistry: AC (activated carboxy-terminated), ALD (aldehyde-terminated), and MT (methyl-terminated). The results, obtained by atomic force microscopy, showed that surface functionalization has a large effect on the surface phage coverage (46.8%, 49.4%, 4.2%, and 5.2% for bare, AC-, ALD-, and MT-functionalized resonators, respectively). In addition, a direct correlation of the observed surface phage coverage with the quantity of subsequently captured streptavidin-coated microbeads was found by scanning electron microscopy and by resonance frequency measurements of the biosensors. The differences in surface phage coverage on the differently functionalized surfaces may then be used to pattern the phage probe layer onto desired parts of the sensor surface to enhance the detection capabilities of ME biosensors.


Assuntos
Bacteriófagos/fisiologia , Bioensaio/instrumentação , Técnicas Biossensoriais/instrumentação , Separação Imunomagnética/instrumentação , Magnetismo/instrumentação , Bacteriófagos/ultraestrutura , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento
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