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1.
J Am Chem Soc ; 146(10): 6686-6696, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38425051

RESUMO

Naturally evolved metabolons have the ability to assemble and disassemble in response to environmental stimuli, allowing for the rapid reorganization of chemical reactions in living cells to meet changing cellular needs. However, replicating such capability in synthetic metabolons remains a challenge due to our limited understanding of the mechanisms by which the assembly and disassembly of such naturally occurring multienzyme complexes are controlled. Here, we report the synthesis of chemical- and light-responsive protein cages for assembling synthetic metabolons, enabling the dynamic regulation of enzymatic reactions in living cells. Particularly, a chemically responsive domain was fused to a self-assembled protein cage subunit, generating engineered protein cages capable of displaying proteins containing cognate interaction domains on their surfaces in response to small molecular cues. Chemical-induced colocalization of sequential enzymes on protein cages enhances the specificity of the branched deoxyviolacein biosynthetic reactions by 2.6-fold. Further, by replacing the chemical-inducible domain with a light-inducible dimerization domain, we created an optogenetic protein cage capable of reversibly recruiting and releasing targeted proteins onto and from the exterior of the protein cages in tens of seconds by on-off of blue light. Tethering the optogenetic protein cages to membranes enables the formation of light-switchable, membrane-bound metabolons, which can repeatably recruit-release enzymes, leading to the manipulation of substrate utilization across membranes on demand. Our work demonstrates a powerful and versatile strategy for constructing dynamic metabolons in engineered living cells for efficient and controllable biocatalysis.


Assuntos
Complexos Multienzimáticos , Proteínas , Proteínas/química , Complexos Multienzimáticos/química
2.
Small ; : e2309773, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461545

RESUMO

An emerging carbothermal shock method is an ultra-convenient strategy for synthesizing high-entropy alloys (HEAs), in which the intelligent combination of carbon support and HEAs can be serve as a decisive factor for interpreting the trade-off relationship between conductive gene and dielectric gene. However, the feedback mechanism of HEAs ordering degree on electromagnetic (EM) response in 2-18 GHz has not been comprehensively demystified. Herein, while lignin-based carbon fiber paper (L-CFP) as carbon support, L-CFP/FeCoNiCuZn-X with is prepared by carbothermal shock method. The reflection loss of -82.6 dB with thickness of 1.31 mm is achieved by means of pointing electron enrichment within L-CFP/FeCoNiCuZn HEAs heterointerfaces verified by theoretical calculations. Simultaneously, low-frequency evolution with high-intensity and broadband EM response relies on a "sacrificing" strategy achieved by construction of polymorphic L-CFP/semi-disordered-HEAs heterointerfaces. The practicality of L-CFP/FeCoNiCuZn-X in complex environments is given prominence to thermal conductivity, hydrophobicity, and electrocatalytic property. This work is of great significance for insightful mechanism analysis of HEAs in the application of electromagnetic wave absorption.

3.
Appl Opt ; 62(1): 217-226, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36606868

RESUMO

In order to ensure optimal optical performance, primary mirror assembly must be impervious to environmental influences. These environmental influences include gravity, assembly error, and thermal change, under which external loads are imposed on the mirror. The external loads degrade the mirror surface accuracy and cause misalignment between mirrors. In this paper, a tripod flexure with a flexible hinge is designed to alleviate the influence of the external load on the surface accuracy of a 2 m primary mirror. This structure can effectively release the rotational freedom, provide a certain translational flexibility, and yield high axial stiffness. The axial stiffness is used to increase the frequency of the primary mirror assembly. According to the fast optimization model, the derivation of close form compliance equations is developed to characterize the flexibility, and parameter optimization is done to achieve the maximum performance. Then a finite element analysis and test are used to verify the final design. The results show that the index requirements of the 2 m primary mirror have been met.

4.
Neural Plast ; 2023: 2741287, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38099081

RESUMO

Background: Obsessive-compulsive disorder (OCD) is frequently treated using a combination of counseling, drugs, and, more recently various transcranial stimulation protocols, but all require several weeks to months for clinically significant improvement, so there is a need for treatments with faster onset. This study investigated whether an accelerated high-dose theta burst stimulation (ahTBS) protocol significantly improves the efficacy of OCD compared to traditional 1-Hz repetitive transcranial magnetic stimulation (rTMS) in the routine clinical setting. Method: Forty-five patients with OCD were randomized into two groups and treated with ahTBS or 1-Hz rTMS for 5 days. Patients were assessed at baseline at the end of treatment using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). Results: After 5 days of treatment, there was a significant decrease in Y-BOCS scores in both groups (p < 0.001), and the difference between the two groups was not statistically significant (group × time interaction, F = 1.90, p=0.18). There was also no statistically significant difference in other secondary outcome indicators, including depression, anxiety symptoms, and response rate. However, the ahTBS group had a greater trend in response rate. Neuropsychological testing showed no negative cognitive side effects of either treatment. Conclusion: Accelerated high-dose TBS is as safe and has comparable short-term efficacy to traditional 1-Hz rTMS for the clinical treatment of OCD. Further research is needed to explore optimal ahTBS parameters, validate the utility of this treatment modality, and identify factors predictive of rapid clinical response to guide clinical decision-making. This trial is registered with NCT05221632.


Assuntos
Transtorno Obsessivo-Compulsivo , Estimulação Magnética Transcraniana , Humanos , Estimulação Magnética Transcraniana/métodos , Projetos de Pesquisa , Transtorno Obsessivo-Compulsivo/terapia , Testes Neuropsicológicos , Resultado do Tratamento
5.
World J Microbiol Biotechnol ; 39(12): 352, 2023 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-37864750

RESUMO

Formate dehydrogenase (FDH) is a D-2-hydroxy acid dehydrogenase, which can reversibly reduce CO2 to formate and thus act as non-photosynthetic CO2 reductase. In order to increase catalytic efficiency of formate dehydrogenase for CO2 reduction, two mutants V328I/F285W and V354G/F285W were obtained of which reduction activity was about two times more than the parent CbFDHM2, and the formate production from CO2 catalyzed by mutants were 2.9 and 2.7-fold higher than that of the parent CbFDHM2. The mutants had greater potential in CO2 reduction. The optimal temperature for V328I/F285W and V354G/F285W was 55 °C, and they showed increasement of relative activity under 45 °C to 55 °C compared with parent. The optimal pH for the mutants was 9.0, and they showed excellent stability in pH 4.0-11.5. The kcat/Km values of mutants were 1.75 times higher than that of the parent. Then the molecular basis for its improvement of biochemical characteristics were preliminarily elucidated by computer-aided methods. All of these results further established a solid foundation for molecular modification of formate dehydrogenase and CO2 reduction.


Assuntos
Dióxido de Carbono , Formiato Desidrogenases , Dióxido de Carbono/metabolismo , Formiato Desidrogenases/genética , Formiato Desidrogenases/química , Formiato Desidrogenases/metabolismo , Catálise , Formiatos/metabolismo
6.
Mol Psychiatry ; 26(11): 6747-6755, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33863994

RESUMO

Major depressive disorder (MDD) is a complex state-dependent psychiatric illness for which biomarkers linking psychophysical, biochemical, and psychopathological changes remain yet elusive, though. Earlier studies demonstrate reduced GABA in lower-order occipital cortex in acute MDD leaving open its validity and significance for higher-order visual perception, though. The goal of our study is to fill that gap by combining psychophysical investigation of visual perception with measurement of GABA concentration in middle temporal visual area (hMT+) in acute depressed MDD. Psychophysically, we observe a highly specific deficit in visual surround motion suppression in a large sample of acute MDD subjects which, importantly, correlates with symptom severity. Both visual deficit and its relation to symptom severity are replicated in the smaller MDD sample that received MRS. Using high-field 7T proton Magnetic resonance spectroscopy (1H-MRS), acute MDD subjects exhibit decreased GABA concentration in visual MT+ which, unlike in healthy subjects, no longer correlates with their visual motion performance, i.e., impaired SI. In sum, our combined psychophysical-biochemical study demonstrates an important role of reduced occipital GABA for altered visual perception and psychopathological symptoms in acute MDD. Bridging the gap from the biochemical level of occipital GABA over visual-perceptual changes to psychopathological symptoms, our findings point to the importance of the occipital cortex in acute depressed MDD including its role as candidate biomarker.


Assuntos
Transtorno Depressivo Maior , Depressão , Humanos , Lobo Occipital/química , Espectroscopia de Prótons por Ressonância Magnética , Percepção Visual , Ácido gama-Aminobutírico
7.
Biotechnol Bioeng ; 119(1): 226-235, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34687217

RESUMO

Solventogenesis and sporulation of clostridia are the main responsive adaptations to the acidic environment during acetone-butanol-ethanol (ABE) fermentation. It was hypothesized that five orphan histidine kinases (HKs) including Cac3319, Cac0323, Cac0903, Cac2730, and Cac0437 determined the cell fates between sporulation and solventogenesis. In this study, the comparative genomic analysis revealed that a mutation in cac0437 appeared to contribute to the nonsporulating feature of ATCC 55025. Hence, the individual and interactive roles of five HKs in regulating cell growth, metabolism, and sporulation were investigated. The fermentation results of mutants with different HK expression levels suggested that cac3319 and cac0437 played critical roles in regulating sporulation and acids and butanol biosynthesis. Morphological analysis revealed that cac3319 knockout abolished sporulation (Stage 0) whereas cac3319 overexpression promoted spore development (Stage VII), and cac0437 knockout initiated but blocked sporulation before Stage II, indicating the progression of sporulation was altered through engineering HKs. By combinatorial HKs knockout, the interactive effects between two different HKs were investigated. This study elucidated the regulatory roles of HKs in clostridial differentiation and demonstrated that HK engineering can be effectively used to control sporulation and enhance butanol biosynthesis.


Assuntos
Proteínas de Bactérias , Butanóis/metabolismo , Clostridium acetobutylicum , Histidina Quinase , Esporos Bacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clostridium acetobutylicum/enzimologia , Clostridium acetobutylicum/genética , Clostridium acetobutylicum/metabolismo , Clostridium acetobutylicum/fisiologia , Fermentação , Histidina Quinase/genética , Histidina Quinase/metabolismo , Engenharia Metabólica
8.
Appl Microbiol Biotechnol ; 106(22): 7563-7575, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36287220

RESUMO

Serine/threonine protein kinases (STKs) are important for signal transduction and involved in multiple physiological processes, including cell growth, central metabolism, and sporulation in bacteria. However, the role of STKs in solventogenic clostridia remains unclear. Here, we identified and comprehensively investigated six STK candidates in Clostridium beijerinckii. These STKs were classified into four groups with distinct characteristics via analysis of genetic organizations, prediction of protein domains, and multiple sequence alignment. Cbei0566 is a member of the PrkA family with 41% identity to PrkA from Bacillus subtilis, and both Cbei0666 and Cbei0813 are two-component-like STKs. Cbei1151 and Cbei1929 belong to the Hanks family STKs and consist of a cytoplasmic catalytic domain, a transmembrane region, and extracellular sensor domains. In-frame deletion mutants of cbei0566, cbei0666, cbei1929, and cbei2661 displayed similar cell growth with wild type. Both Δcbei0666 and Δcbei2661 improved acetone-butanol-ethanol (ABE) production by 14.3% (19.2 g/L vs. 16.8 g/L), and the sporulation frequencies of Δcbei0566, Δcbei1929, and Δcbei2661 significantly decreased to 35.5%, 55.1% and 44.8%, respectively. The restored phenotypes after genetic complementation demonstrated their direct link to STKs deletion. Remarkably, overexpressing cbei0566 contributed to 41.5% more spore formation and cbei1929 overexpression enhanced ABE production from 19.3 to 24.2 g/L, along with 25% less acids. These results revealed that Cbei0566 and Cbei1929 had prominent regulatory functions. This study expands the current knowledge of the existence and functions of STKs in prokaryotes and highlights the importance of STK-mediated signaling networks in developing superior strains. KEY POINTS: • First reported serine/threonine protein kinases in solventogenic clostridia • Six STKs with distinct properties possessed diverse functions in C. beijerinckii • Cbei1929 and Cbei0566 remarkably regulated solventogenesis and sporulation.


Assuntos
Clostridium beijerinckii , Clostridium beijerinckii/genética , Clostridium beijerinckii/metabolismo , Proteínas Serina-Treonina Quinases , Fermentação , Etanol/metabolismo , Butanóis/metabolismo , 1-Butanol/metabolismo , Clostridium/metabolismo , Treonina/metabolismo , Serina/metabolismo
9.
Angew Chem Int Ed Engl ; 61(52): e202214001, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36288455

RESUMO

Cells use self-assembled biomaterials such as lipid membranes or proteinaceous shells to coordinate thousands of reactions that simultaneously take place within crowded spaces. However, mimicking such spatial organization for synthetic applications in engineered systems remains a challenge, resulting in inferior catalytic efficiency. In this work, we show that protein cages as an ideal scaffold to organize enzymes to enhance cascade reactions both in vitro and in living cells. We demonstrate that not only enzyme-enzyme distance but also the improved Km value contribute to the enhanced reaction rate of cascade reactions. Three sequential enzymes for lycopene biosynthesis have been co-localized on the exterior of the engineered protein cages in Escherichia coli, leading to an 8.5-fold increase of lycopene production by streamlining metabolic flux towards its biosynthesis. This versatile system offers a powerful tool to achieve enzyme spatial organization for broad applications in biocatalysis.


Assuntos
Escherichia coli , Proteínas , Licopeno , Proteínas/metabolismo , Biocatálise , Escherichia coli/metabolismo , Enzimas/metabolismo
10.
Biotechnol Bioeng ; 118(7): 2770-2780, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33871069

RESUMO

Microorganisms harbor bulks of functionally similar or undefined genes, which belong to paralogous gene family. There is a necessity of exploring combinatorial or interactive functions of these genes, but conventional loss-of-function strategy with one-by-one rounds suffers extremely low efficiency for generating mutant libraries with all gene permutations. Here, taking histidine kinases (HKs) in Clostridium acetobutylicum as a proof-of-concept, we developed a multi-plasmid cotransformation strategy for generating all theoretical HKs combinations in one round. For five HKs with 31 theoretical combinations, the library containing 22 mutants within all the possible HKs-inactivated combinations was constructed with 11 days compared to 242 days by conventional strategy, while the other 9 combinations cannot survive. Six mutants with the enhanced butanol production and tolerance were obtained with changes of cell development during fermentation, one of which could produce 54.2% more butanol (56.4% more solvents), while the butanol production of other mutants was unchanged or decreased. The cotransformation strategy demonstrated potentials for fast exploring pleiotropic function of paralogous family genes in cell survival, cell development, and target product metabolism.


Assuntos
Butanóis/metabolismo , Clostridium acetobutylicum , Histidina Quinase , Engenharia Metabólica , Mutação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Clostridium acetobutylicum/genética , Clostridium acetobutylicum/metabolismo , Histidina Quinase/genética , Histidina Quinase/metabolismo
11.
Nano Lett ; 18(10): 6150-6156, 2018 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-30132675

RESUMO

Synthetic membranes usually suffer from a ubiquitous trade-off between permeability and selectivity. Carbon nanotube (CNT)-based hybrid materials have shown attractive properties in high-performance membrane preparation; however, the aggregation of random CNTs in polymer remains a great challenge. Herein, the aligned and open-ended CNT/(polydimethylsiloxane) PDMS membranes are controllably fabricated to form a hamburger-like structure that possesses nanochannels (∼10 nm) in the intermediate layer as well as angstrom cavities in the embedded PDMS. These aligned CNT membranes surpass the filling content limitation of the nonaligned CNT/PDMS membrane (37.4 wt % versus ∼10 wt %), leading to excellent mechanical properties and a multiplying performance increase of mass flux and selectivity for the separation of alcohols. The membranes break the permeability-selectivity trade-off with both parameters remarkably increasing (maximum 9 times) for bioalcohol separation. The established pervaporative-ultrafiltration mechanism indicates that the penetrant molecules preferentially pass through CNT internal nanochannels with increasing membrane permeability, thereby paving a way to nanoscale design of highly efficient channeled membranes for separation application.

12.
Appl Microbiol Biotechnol ; 102(18): 8107-8119, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29987383

RESUMO

Vitamin B1 (VB1) is an essential coenzyme for carbohydrate metabolism and involved in energy generation in most organisms. In this study, we found that insufficient biosynthesis of VB1 in Clostridium acetobutylicum ATCC 824 is a major limiting factor for efficient acetone-butanol-ethanol (ABE) fermentation. In order to improve the fermentation performance of C. acetobutylicum ATCC 824, the VB1 biosynthesis pathway was strengthened by overexpressing the thiC, thiG, and thiE genes. The engineered strain 824(thiCGE) showed enhanced VB1 and energy synthesis, resulting in better growth, faster sugar consumption, higher solvents production, and lower acids formation than the wild-type strain in both VB1 free and normal P2 medium (1 mg/L). Compared with the wild-type strain, 824(thiCGE) produced 13.0 ± 0.1% or 12.7 ± 1.2% more butanol in VB1 free P2 medium when glucose or xylose was used as the substrate, respectively. When mixed sugar (glucose:xylose = 2:1) was used as the substrate in VB1 free P2 medium, the xylose consumption rate and butanol titer of 824(thiCGE) were 45.8 ± 1.9% and 20.4 ± 0.3% higher than those of the wild-type strain. All these results demonstrated that this metabolic engineering strategy could provide a new and effective way to improve the cellular performance of solventogenic clostridia. In addition, it may have some potential application value in ABE fermentation using simple medium and/or lignocellulosic biomass.


Assuntos
Clostridium acetobutylicum/metabolismo , Fermentação , Tiamina/biossíntese , Butanóis/metabolismo , Clostridium acetobutylicum/genética , Meios de Cultura , Genes Bacterianos , Glucose/metabolismo , Engenharia Metabólica , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Xilose/metabolismo
13.
Biotechnol Bioeng ; 113(1): 120-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26032697

RESUMO

Butanol is considered as an advanced biofuel, the development of which is restricted by the intensive energy consumption of product recovery. A novel two-stage gas stripping-pervaporation process integrated with acetone-butanol-ethanol (ABE) fermentation was developed for butanol recovery, with gas stripping as the first-stage and pervaporation as the second-stage using the carbon nanotubes (CNTs) filled polydimethylsiloxane (PDMS) mixed matrix membrane (MMM). Compared to batch fermentation without butanol recovery, more ABE (27.5 g/L acetone, 75.5 g/L butanol, 7.0 g/L ethanol vs. 7.9 g/L acetone, 16.2 g/L butanol, 1.4 g/L ethanol) were produced in the fed-batch fermentation, with a higher butanol productivity (0.34 g/L · h vs. 0.30 g/L · h) due to reduced butanol inhibition by butanol recovery. The first-stage gas stripping produced a condensate containing 155.6 g/L butanol (199.9 g/L ABE), which after phase separation formed an organic phase containing 610.8 g/L butanol (656.1 g/L ABE) and an aqueous phase containing 85.6 g/L butanol (129.7 g/L ABE). Fed with the aqueous phase of the condensate from first-stage gas stripping, the second-stage pervaporation using the CNTs-PDMS MMM produced a condensate containing 441.7 g/L butanol (593.2 g/L ABE), which after mixing with the organic phase from gas stripping gave a highly concentrated product containing 521.3 g/L butanol (622.9 g/L ABE). The outstanding performance of CNTs-PDMS MMM can be attributed to the hydrophobic CNTs giving an alternative route for mass transport through the inner tubes or along the smooth surface of CNTs. This gas stripping-pervaporation process with less contaminated risk is thus effective in increasing butanol production and reducing energy consumption.


Assuntos
1-Butanol/isolamento & purificação , 1-Butanol/metabolismo , Acetona/metabolismo , Etanol/metabolismo , Dimetilpolisiloxanos/metabolismo , Fermentação , Gases , Nanotubos
14.
Appl Microbiol Biotechnol ; 99(2): 1011-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25472438

RESUMO

Clostridium acetobutylicum JB200, a mutant strain of C. acetobutylicum ATCC 55025 obtained through strain evolution in a fibrous bed bioreactor, had high butanol tolerance and produced up to ~21 g/L butanol from glucose in batch fermentation, an improvement of ~67 % over the parental strain (~12.6 g/L). Comparative genomic analysis revealed a single-base deletion in the cac3319 gene leading to C-terminal truncation in its encoding histidine kinase (HK) in JB200. To study the effects of cac3319 mutation on cell growth and fermentation, the cac3319 gene in ATCC 55025 was disrupted using the ClosTron group II intron-based gene inactivation system. Compared to ATCC 55025, the cac3319 HK knockout mutant, HKKO, produced 44.4 % more butanol (18.2 ± 1.3 vs. 12.6 ± 0.2 g/L) with a 90 % higher productivity (0.38 ± 0.03 vs. 0.20 ± 0.02 g/L h) due to increased butanol tolerance, confirming, for the first time, that cac3319 plays an important role in regulating solvent production and tolerance in C. acetobutylicum. This work also provides a novel metabolic engineering strategy for generating high-butanol-tolerant and high-butanol-producing strains for industrial applications.


Assuntos
1-Butanol/metabolismo , Clostridium acetobutylicum/genética , Microbiologia Industrial , Engenharia Metabólica/métodos , Proteínas Quinases/metabolismo , Clonagem Molecular , Clostridium acetobutylicum/metabolismo , Meios de Cultura , DNA Bacteriano/genética , Fermentação , Glucose/metabolismo , Histidina Quinase , Mutação , Plasmídeos/genética , Análise de Sequência de DNA , Solventes/química
15.
Appl Microbiol Biotechnol ; 98(8): 3463-74, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24535254

RESUMO

Butanol has recently gained increasing interest due to escalating prices in petroleum fuels and concerns on the energy crisis. However, the butanol production cost with conventional acetone-butanol-ethanol fermentation by Clostridium spp. was higher than that of petrochemical processes due to the low butanol titer, yield, and productivity in bioprocesses. In particular, a low butanol titer usually leads to an extremely high recovery cost. Conventional biobutanol recovery by distillation is an energy-intensive process, which has largely restricted the economic production of biobutanol. This article thus reviews the latest studies on butanol recovery techniques including gas stripping, liquid-liquid extraction, adsorption, and membrane-based techniques, which can be used for in situ recovery of inhibitory products to enhance butanol production. The productivity of the fermentation system is improved efficiently using the in situ recovery technology; however, the recovered butanol titer remains low due to the limitations from each one of these recovery technologies, especially when the feed butanol concentration is lower than 1 % (w/v). Therefore, several innovative multi-stage hybrid processes have been proposed and are discussed in this review. These hybrid processes including two-stage gas stripping and multi-stage pervaporation have high butanol selectivity, considerably higher energy and production efficiency, and should outperform the conventional processes using single separation step or method. The development of these new integrated processes will give a momentum for the sustainable production of industrial biobutanol.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Butanóis/isolamento & purificação , Butanóis/metabolismo , Clostridium/metabolismo , Fermentação
16.
Comput Biol Med ; 174: 108446, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631118

RESUMO

OBJECTIVE: Depression and anxiety, prevalent coexisting mood disorders, pose a clinical challenge in accurate differentiation, hindering effective healthcare interventions. This research addressed this gap by employing a streamlined Symptom Checklist 90 (SCL-90) designed to minimize patient response burden. Utilizing machine learning algorithms, the study sought to construct classification models capable of distinguishing between depression and anxiety. METHODS: The study included 4262 individuals currently experiencing depression alone (n = 2998), anxiety alone (n = 716), or both depression and anxiety (n = 548). Counterfactual diagnosis was used to construct a causal network on the dataset. Employing a causal network, the SCL-90 was simplified. Items that have causality with only depression, only anxiety and both depression and anxiety were selected, and these streamlined items served as input features for four distinct machine learning algorithms, facilitating the creation of classification models for distinguishing depression and anxiety. RESULTS: Cross-validation demonstrated the performance of the classification models with the following metrics: (1) K-nearest neighbors (AUC = 0.924, Acc = 92.81 %); (2) support vector machine (AUC = 0.937, Acc = 94.38 %); (3) random forest (AUC = 0.918, Acc = 94.38 %); and (4) adaptive boosting (AUC = 0.882, Acc = 94.38 %). Notably, the support vector machine excelled, with the highest AUC and superior accuracy. CONCLUSION: Incorporating the simplified SCL-90 and machine learning presents a promising, efficient, and cost-effective tool for the precise identification of depression and anxiety.


Assuntos
Ansiedade , Depressão , Aprendizado de Máquina , Humanos , Feminino , Masculino , Adulto , Depressão/diagnóstico , Ansiedade/diagnóstico , Pessoa de Meia-Idade , Transtornos de Ansiedade/diagnóstico
17.
ACS Appl Mater Interfaces ; 16(11): 14015-14025, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38446708

RESUMO

With the rapid advances in imperceptible and epidermal electronics, the research on ultraflexible organic light-emitting diodes (OLEDs) has become increasingly significant, owing to their excellent flexibility and conformability to the human body. It is highly desirable to develop submicrometer-thick ultraflexible OLEDs to enable the devices to seamlessly conform to the surface of arbitrary-shaped objects and still function properly. However, it remains a huge challenge for currently reported OLEDs due to the lack of an appropriate stripping strategy. Here, for the first time, we develop a facile photoregulated stripping strategy for the fabrication of high-performance ultraflexible OLEDs with submicron thickness. Under ultraviolet (UV) irradiation, the surface adhesion force of the ultrathin photopolymer membrane can be adjusted from 16.9 to 5.1 N/m, thereby effectively controlling the laminating and detaching process. Based on this strategy, the resultant device thickness is as low as 0.821 µm, which is the lowest record among flexible OLEDs reported to date. More remarkably, excellent electrical properties with a maximum current efficiency (CE) of 62.5 cd/A, an external quantum efficiency (EQE) of 17.8%, and a low turn-on voltage of 2.5 V are realized, which are superior to almost all of the reported ultraflexible OLEDs with thicknesses below 10 µm. Based on versatile ultraflexible OLEDs, all-organic and skin-mounted displays are successfully realized by employing a conformable organic thin-film transistor (OTFT) as the driver. This work offers a feasible strategy for advancing OLEDs from flexible to ultraflexible, showing significant application potential in future epidermal electronics and conformal displays.

18.
J Biotechnol ; 379: 1-5, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37944902

RESUMO

Considering global economic and environmental -benefits, green renewable biofuels such as ethanol and butanol are considered as sustainable alternatives to fossil fuels. Thus, developing a co-culture strategy for ethanol and butanol production by Saccharomyces cerevisiae and Clostridium beijerinckii has emerged as a promising approach for biofuel production from lignocellulosic biomass. This study developed a co-culture of S. cerevisiae and C. beijerinckii for ethanol and butanol production from non-detoxified corn stover hydrolysate. By firstly inoculating 3 % S. cerevisiae and then 7 % C. beijerinckii with 8-10 h time intervals, the optimized co-culture process gave 24.0 g/L ABE (20.8 g/L ethanol and 2.4 g/L butanol), obtaining ABE yield and productivity of 0.421 g/g and 0.55 g/L/h. The demonstrated co-culture strategy made full use of hexose and pentose in hydrolysate and contributed to total yield and efficiency compared to conventional ethanol or ABE fermentation, indicating its great potential for developing economically feasible and sustainable bioalcohols production.


Assuntos
Clostridium beijerinckii , Saccharomyces cerevisiae , Etanol , Zea mays , Técnicas de Cocultura , Acetona , Butanóis , 1-Butanol , Fermentação
19.
Front Hum Neurosci ; 18: 1404398, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903410

RESUMO

A neurogenic dysphagia is dysphagia caused by problems with the central and peripheral nervous systems, is particularly prevalent in conditions such as Parkinson's disease and stroke. It significantly impacts the quality of life for affected individuals and causes additional burdens, such as malnutrition, aspiration pneumonia, asphyxia, or even death from choking due to improper eating. Physical therapy offers a non-invasive treatment with high efficacy and low cost. Evidence supporting the use of physical therapy in dysphagia treatment is increasing, including techniques such as neuromuscular electrical stimulation, sensory stimulation, transcranial direct current stimulation, and repetitive transcranial magnetic stimulation. While initial studies have shown promising results, the effectiveness of specific treatment regimens still requires further validation. At present, there is a lack of scientific evidence to guide patient selection, develop appropriate treatment regimens, and accurately evaluate treatment outcomes. Therefore, the primary objectives of this review are to review the results of existing research, summarize the application of physical therapy in dysphagia management, we also discussed the mechanisms and treatments of physical therapy for neurogenic dysphagia.

20.
Nanomicro Lett ; 16(1): 202, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782778

RESUMO

Single-atom (SA) catalysts with nearly 100% atom utilization have been widely employed in electrolysis for decades, due to the outperforming catalytic activity and selectivity. However, most of the reported SA catalysts are fixed through the strong bonding between the dispersed single metallic atoms with nonmetallic atoms of the substrates, which greatly limits the controllable regulation of electrocatalytic activity of SA catalysts. In this work, Pt-Ni bonded Pt SA catalyst with adjustable electronic states was successfully constructed through a controllable electrochemical reduction on the coordination unsaturated amorphous Ni(OH)2 nanosheet arrays. Based on the X-ray absorption fine structure analysis and first-principles calculations, Pt SA was bonded with Ni sites of amorphous Ni(OH)2, rather than conventional O sites, resulting in negatively charged Ptδ-. In situ Raman spectroscopy revealed that the changed configuration and electronic states greatly enhanced absorbability for activated hydrogen atoms, which were the essential intermediate for alkaline hydrogen evolution reaction. The hydrogen spillover process was revealed from amorphous Ni(OH)2 that effectively cleave the H-O-H bond of H2O and produce H atom to the Pt SA sites, leading to a low overpotential of 48 mV in alkaline electrolyte at -1000 mA cm-2 mg-1Pt, evidently better than commercial Pt/C catalysts. This work provided new strategy for the controllable modulation of the local structure of SA catalysts and the systematic regulation of the electronic states.

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