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Room-temperature optoelectronic devices that operate at short-wavelength and mid-wavelength infrared ranges (one to eight micrometres) can be used for numerous applications1-5. To achieve the range of operating wavelengths needed for a given application, a combination of materials with different bandgaps (for example, superlattices or heterostructures)6,7 or variations in the composition of semiconductor alloys during growth8,9 are used. However, these materials are complex to fabricate, and the operating range is fixed after fabrication. Although wide-range, active and reversible tunability of the operating wavelengths in optoelectronic devices after fabrication is a highly desirable feature, no such platform has been yet developed. Here we demonstrate high-performance room-temperature infrared optoelectronics with actively variable spectra by presenting black phosphorus as an ideal candidate. Enabled by the highly strain-sensitive nature of its bandgap, which varies from 0.22 to 0.53 electronvolts, we show a continuous and reversible tuning of the operating wavelengths in light-emitting diodes and photodetectors composed of black phosphorus. Furthermore, we leverage this platform to demonstrate multiplexed nondispersive infrared gas sensing, whereby multiple gases (for example, carbon dioxide, methane and water vapour) are detected using a single light source. With its active spectral tunability while also retaining high performance, our work bridges a technological gap, presenting a potential way of meeting different requirements for emission and detection spectra in optoelectronic applications.
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An exciton is the bosonic quasiparticle of electron-hole pairs bound by the Coulomb interaction1. Bose-Einstein condensation of this exciton state has long been the subject of speculation in various model systems2,3, and examples have been found more recently in optical lattices and two-dimensional materials4-9. Unlike these conventional excitons formed from extended Bloch states4-9, excitonic bound states from intrinsically many-body localized states are rare. Here we show that a spin-orbit-entangled exciton state appears below the Néel temperature of 150 kelvin in NiPS3, an antiferromagnetic van der Waals material. It arises intrinsically from the archetypal many-body states of the Zhang-Rice singlet10,11, and reaches a coherent state assisted by the antiferromagnetic order. Using configuration-interaction theory, we determine the origin of the coherent excitonic excitation to be a transition from a Zhang-Rice triplet to a Zhang-Rice singlet. We combine three spectroscopic tools-resonant inelastic X-ray scattering, photoluminescence and optical absorption-to characterize the exciton and to demonstrate an extremely narrow excitonic linewidth below 50 kelvin. The discovery of the spin-orbit-entangled exciton in antiferromagnetic NiPS3 introduces van der Waals magnets as a platform to study coherent many-body excitons.
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Despite the importance of the stability of the 2D catalysts in harsh electrolyte solutions, most studies have focused on improving the catalytic performance of molybdenum disulfide (MoS2) catalysts rather than the sustainability of hydrogen evolution. In previous studies, the vulnerability of MoS2 crystals is reported that the moisture and oxygen molecules can cause the oxidation of MoS2 crystals, accelerating the degradation of crystal structure. Therefore, optimization of catalytic stability is crucial for approaching practical applications in 2D catalysts. Here, it is proposed that monolayered MoS2 catalysts passivated with an atomically thin hexagonal boron nitride (h-BN) layer can effectively sustain hydrogen evolution reaction (HER) and demonstrate the ultra-high current density (500 mA cmâ»2 over 11 h) and super stable (64 h at 150 mA cmâ»2) catalytic performance. It is further confirmed with density functional theory (DFT) calculations that the atomically thin h-BN layer effectively prevents direct adsorption of water/acid molecules while allowing the protons to be adsorbed/penetrated. The selective penetration of protons and prevention of crystal structure degradation lead to maintained catalytic activity and maximized catalytic stability in the h-BN covered MoS2 catalysts. These findings propose a promising opportunity for approaching the practical application of 2D MoS2 catalysts having long-term stability at high-current operation.
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Using data from the 2022 Korea Community Health Survey (nâ =â 13â 320), this study investigated helmet use and related factors among Korean adults using personal mobility devices, without distinguishing between private and hired users. Among mobility device users, 32.1% responded that they always wore a helmet. The proportion of helmet use was 35.2% among men, 25.8% among women, 29.2% among those aged 19-44 years, 42.3% among those aged 45-64 years and 26.6% among those aged 65 years or older. Furthermore, those who drank less frequently and were physically active were more likely to wear helmets. Moreover, people who always wore a seat belt when driving a car or sitting in the rear seat and people who always wore a helmet when riding a motorcycle were more likely to wear a helmet while using electric personal mobility devices. Approximately one-third of users always wore a helmet. The helmet-wearing rate was related to general characteristics such as gender and education level, and to safety behaviors such as wearing a seat belt when driving a car, sitting in the rear seat of a car, or when riding a motorcycle. In addition to considering personal characteristics investigated in this study, the helmet-wearing rate should be improved through policies or systems at the national or regional levels.
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Dispositivos de Proteção da Cabeça , Humanos , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Masculino , Feminino , República da Coreia , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Cintos de Segurança/estatística & dados numéricos , Inquéritos EpidemiológicosRESUMO
Robust and accurate three-dimensional localization is essential for personal navigation, emergency rescue, and worker monitoring in indoor environments. For localization technology to be employed in various applications, it is necessary to reduce infrastructure dependence and limit the maximum error bound. This study aims to accurately estimate the location of various people using smartphones in a building with a cloud platform-based localization system. The proposed technology is modularized in a hierarchical structure to sequentially estimate the floor and location. This system comprises four localization modules: course level detection, fine level detection (FLD), fine location tracking (FLT), and level change detection (LCD). Each module operates organically according to the current user status. The position estimation range is defined as a total of three phases, and an appropriate location estimation module suitable for the corresponding phase operates to estimate the user's location gradually and precisely. When the user's floor is determined by an FLD, the two-dimensional position of the user is estimated by an FLT module that tracks the user's position by comparing the received signal strength indicator vector sequence and radio map. Also, LCD recognizes the user's floor change and converts the user's phase. To verify the proposed technology, various experiments were conducted in a six-story building, and an average accuracy of less than 2 m was obtained.
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We are writing because we have a number of concerns about the Takakura et al. [...].
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Terapia por Acupuntura , Dor Crônica , Cervicalgia , Humanos , Terapia por Acupuntura/métodos , Terapia por Acupuntura/estatística & dados numéricos , Cervicalgia/terapia , Método Duplo-Cego , Dor Crônica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Japão , População do Leste AsiáticoRESUMO
Walking can have a positive impact on cognitive function in adolescents. This study aimed to compare the effects of walking with sneakers and barefoot on cognitive ability in adolescents. Fifty-nine adolescent male students were included in the study and assigned to the control (n = 20), sneaker (n = 19), and barefoot (n = 20) groups. The barefoot and sneakers group performed a 40-min walking exercise four times a week for 12 weeks during the morning physical activity time, while the control group performed self-study. Electroencephalogram (EEG) and brain activity variables were measured before and after the exercise program. The results showed that after 12 weeks, the barefoot group had a significant decrease in Gamma and H-beta waves and a significant increase in sensorimotor rhythm (SMR) and Alpha waves. Conversely, the control group showed a significant decrease in SMR waves and increase in Theta waves. The sneaker group showed a significant decrease in SMR waves alone. In an eyes-open resting state, the barefoot group showed a significant increase in H-beta, M-beta, SMR, and Alpha waves. The barefoot group also had a significant increase in cognitive speed and concentration and a significant decrease in brain stress. Taken together, barefoot walking can effectively enhance cognitive ability in adolescents, as demonstrated by the significant variation in EEG activity. This research highlights the potential benefits of barefoot walking as a simple and effective form of exercise for enhancing cognitive function in adolescents.
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BACKGROUND: Information on electrocardiogram (ECG) has not been quantified in obstructive coronary artery disease (ObCAD), despite the deep learning (DL) algorithm being proposed as an effective diagnostic tool for acute myocardial infarction (AMI). Therefore, this study adopted a DL algorithm to suggest the screening of ObCAD from ECG. METHODS: ECG voltage-time traces within a week from coronary angiography (CAG) were extracted for the patients who received CAG for suspected CAD in a single tertiary hospital from 2008 to 2020. After separating the AMI group, those were classified into ObCAD and non-ObCAD groups based on the CAG results. A DL-based model adopting ResNet was built to extract information from ECG data in the patients with ObCAD relative to those with non-ObCAD, and compared the performance with AMI. Moreover, subgroup analysis was conducted using ECG patterns of computer-assisted ECG interpretation. RESULTS: The DL model demonstrated modest performance in suggesting the probability of ObCAD but excellent performance in detecting AMI. The AUC of the ObCAD model adopting 1D ResNet was 0.693 and 0.923 in detecting AMI. The accuracy, sensitivity, specificity, and F1 score of the DL model for screening ObCAD were 0.638, 0.639, 0.636, and 0.634, respectively, while the figures were up to 0.885, 0.769, 0.921, and 0.758 for detecting AMI, respectively. Subgroup analysis showed that the difference between normal and abnormal/borderline ECG groups was not notable. CONCLUSIONS: ECG-based DL model showed fair performance for assessing ObCAD and it may serve as an adjunct to the pre-test probability in patients with suspected ObCAD during the initial evaluation. With further refinement and evaluation, ECG coupled with the DL algorithm may provide potential front-line screening support in the resource-intensive diagnostic pathways.
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Doença da Artéria Coronariana , Aprendizado Profundo , Infarto do Miocárdio , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico , Eletrocardiografia/métodos , AlgoritmosRESUMO
Partial nephrectomy (PN) is a common surgery for small renal masses. The goal is to remove the mass completely while preserving renal function. A precise incision is, therefore, important. However, no specific method for surgical incision in PN exists, although there are several guides for bony structures using three-dimensional (3D) printing methods. Therefore, we tested the 3D printing method to create a surgical guide for PN. We describe the workflow to make the guide, which comprises computed tomography data acquisition and segmentation, incision line creation, surgical guide design, and its use during surgery. The guide was designed with a mesh structure that could be fixed to the renal parenchyma, indicating the projected incision line. During the operation, the 3D-printed surgical guide accurately indicated the incision line, without distortion. An intraoperative sonography was performed to locate the renal mass, which confirmed that the guide was well placed. The mass was completely removed, and the surgical margin was negative. No inflammation or immune reaction occurred during and 1 month after the operation. This surgical guide proved useful during PN for indicating the incision line and was easy to handle, without complications. We, therefore, recommend this tool for PN with improved surgical outcome.
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Neoplasias Renais , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Rim/diagnóstico por imagem , Rim/cirurgia , Tomografia Computadorizada por Raios X , Impressão TridimensionalRESUMO
Medial epicanthoplasty is a crucial component in Asian cosmetic eyelid surgery. Conventional surgical methods have mandated wide undermining for the purpose of sufficient release. However, excessive undermining may result in hypertrophic scar or webbing deformities. To minimize undesirable results, the authors are proposing a novel approach. From March 2010 to December 2017, a triangular resection epicanthoplasty was performed in 421 Asian patients. The authors' procedure consists of triangular skin resection, the release of orbicularis oculi muscle and upper half medial epicanthal tendon, and dog ear correction. No complication regarding scarring or webbing was reported. The revision was performed in 18 cases where the patients wanted additional correction. The triangular resection epicanthoplasty offers both optimal results and minimal scar with relative simplicity.
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Blefaroplastia , Cicatriz Hipertrófica , Humanos , Blefaroplastia/métodos , Cicatriz Hipertrófica/prevenção & controle , Cicatriz Hipertrófica/cirurgia , Povo Asiático , Pálpebras/cirurgia , Músculos Faciais/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Hindfoot malalignment can cause various foot and ankle problems. For better surgical performance and correction of hindfoot malalignments, reliable intraoperative determination of hindfoot alignment is essential. However, there is no standard method for the intraoperative assessment of hindfoot alignment. We devised an intraoperative modified Méary posteroanterior (IOPPA) view to assess intraoperative hindfoot alignment. This study aimed to compare this intraoperative method with other radiographic hindfoot alignment measurements. METHODS: Thirty-seven patients (47 feet) with various foot and ankle conditions scheduled to undergo surgery were prospectively recruited. Before surgery, the Saltzman, long axial, and modified Méary views were taken in a controlled and standardized fashion. IOPPA views were obtained under simulated weight bearing conditions using C-arm fluoroscopy in the operating room before surgery. The relationship between the IOPPA view and the three radiographic hindfoot alignments was evaluated using Pearson's correlation. RESULTS: The mean hindfoot alignment angle was varus 3.50° (CI, varus 1.91 to 5.08) on the Saltzman view, varus 2.00° (CI, varus 0.60 to 3.39) on the long axial view, varus 0.13° (CI, valgus 1.41 to varus 1.67) on the modified Méary view, and varus 1.32° (CI, valgus 0.02 to varus 2.65) on IOPPA view. The IOPPA view and the three other hindfoot alignment views were found to be significantly correlated (r = 0.60 for the Saltzman view, r = 0.50 for the long axial view, r = 0.71 for the modified Méary view, P < .05). The intraobserver ICC (Intraclass Correlation Coefficient) value was 0.974 and interobserver ICC (Intraclass Correlation Coefficient) value was 0.988 for the IOPPA view (P < .001). CONCLUSION: There was a statistically significant correlation between the IOPPA view and the other three hindfoot alignment views. We also found that interobserver and intraobserver ICC values were excellent. This study proposes that the IOPPA view can be used as a reliable intraoperative assessment tool for hindfoot alignment. LEVEL OF EVIDENCE: Prospective study.
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In this study, a homogeneous one-step immunoassay based on switching peptides is presented for the detection of influenza viruses A and B (Inf-A and Inf-B, respectively). The one-step immunoassay represents an immunoassay method that does not involve any washing steps, only treatment of the sample. In this method, fluorescence-labeled switching peptides quantitatively dissociate from the antigen-binding site of immunoglobulin G (IgG). In particular, the one-step immunoassay based on soluble detection antibodies with switching peptides is called a homogeneous one-step immunoassay. The immunoassay developed uses switching peptides labeled with two types of fluorescence dyes (FAM and TAMRA) and detection antibodies labeled with two types of fluorescence quenchers (TQ2 for FAM and TQ3 for TAMRA). The optimal switching peptides for the detection of Inf-A and Inf-B have been selected as L1-peptide and H2-peptide. The interactions between the four kinds of switching peptides and IgG have been analyzed using computational docking simulation and SPR biosensor. The location of labeling for the fluorescence quenchers has been determined based on the distance between the fluorescence dyes of the switching peptides and the fluorescence quenchers, calculated on the basis of the efficiency of fluorescence quenching, using the Förster equation. To demonstrate the feasibility of the one-step immunoassay, binding constants (KD) have been calculated for detection antibodies against Inf-A and Inf-B with target antigens (Inf-A and Inf-B) and switching peptides (L1- and H2-peptides), using an isotherm model. The immunoassay has been demonstrated to be feasible using antigens as well as real samples of Inf-A and Inf-B with a critical cycle number (Ct). The immunoassay has also been compared to other commercially available rapid test kits for Inf-A and Inf-B and found to be far more sensitive for detection of Inf-A and Inf-B over the entire detection range.
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Orthomyxoviridae , Antígenos , Corantes Fluorescentes/química , Imunoensaio/métodos , Imunoglobulina G , Peptídeos/químicaRESUMO
BACKGROUND: Clear cell renal carcinoma is commonly known for its metastasis propensity to outspread to other organs and is asymptomatic in the early stage. Recent studies have shown that deficiencies in CYP11A1 expression can lead to fatal adrenal failure if left untreated and are associated with downstream regulation in various cancer types. However, the molecular mechanisms of CYP11A1 and kidney cancer proliferation remain unclear. METHODS: Normal and renal carcinoma cell lines (HEK293 and Caki-1) were transfected with plasmid encoding CYP11A1 to overexpress the P450scc protein. Cell cycle distribution was investigated using flow cytometry. The expression of proteins related to C-Raf/ERK/JNK/p38 signaling pathways was examined using western blot. RESULTS: We observed that CYP11A1 overexpression suppressed the cyclin B1 and cell-division cycle 2 expression while cyclin-dependent kinases 2 and 4 were unaffected. Cancer cell migration and invasion were suppressed along with epithelial-intermediate metastatic markers Snail and Vimentin. In addition, in CYP11A1-overexpressing Caki-1 cells, cdc2/cyclinB1 was downregulated while the phosphorylation of cdc25c, a G2/M arrest-related upstream signal, was increased. The intrinsic-mitochondrial apoptosis markers were not significantly altered. We also identified that the C-Raf/ERK/JNK/p38 pathway is an important pro-apoptotic mechanism in CYP11A1-overexpressing cell-based models. Our results suggest that CYP11A1 overexpression recovered the disturbed cell cycle arrest distribution in renal carcinoma cell line Caki-1 through G2/M arrest and C-Raf/ERK/JNK pathway. CONCLUSIONS: Our findings may suggest promising new therapeutic targets to suppress kidney cancer proliferation without affecting normal cells, eventually improving the survival of patients with cancer.
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BACKGROUND: The Laparoscopic Approach to Cervical Cancer trial and Surveillance, Epidemiology, and End Results program database study demonstrated that minimally invasive radical hysterectomy was inferior to abdominal radical hysterectomy in terms of disease recurrence and survival. Among risk factors related to poor prognosis after minimally invasive surgery (MIS), tumour spillage during intracorporeal colpotomy became a significant issue. Thus, we designed this trial to evaluate the efficacy and safety of minimally invasive radical hysterectomy using an endoscopic stapler for early-stage cervical cancer. METHODS: This trial is a prospective, multi-centre, open-label, single-arm, non-inferiority phase II study. The nine organisations will participate in this trial after the approval of the institutional review board. Major eligibility criteria include women aged 20 years or older with cervical cancer stage IB1 squamous cell carcinoma, adenocarcinoma, or adenosquamous carcinoma according to the revised 2009 FIGO staging system who will undergo type B2 or C hysterectomy by MIS. The primary endpoint is the 4.5-year disease-free survival (DFS) rate between abdominal radical hysterectomy and MIS using an endoscopic stapler. For calculating the sample size, we hypothesised that the 4.5-year DFS rate after MIS using an endoscopic stapler is assumed to be the same after abdominal radical hysterectomy at 90.9%, and the non-inferiority margin was 7.2%. When we consider a three-year accrual and 4.5-year follow-up, at least 13 events must happen, requiring a total of 111 patients assuming a statistical power of 80% and the one-tailed test of 5% significance. A total of 124 patients is needed, considering a drop-out rate of 10%. DISCUSSION: We expect intracorporeal colpotomy using an endoscopic stapler may prevent tumour spillage during MIS for stage IB1 cervical cancer, showing a comparable prognosis with abdominal radical surgery. TRIAL REGISTRATION: ClinicalTrials.gov ; NCT04370496 ; registration date, May 2020.
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Laparoscopia , Procedimentos Cirúrgicos Robóticos , Neoplasias do Colo do Útero , Adulto , Ensaios Clínicos Fase II como Assunto , Feminino , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Estudos Multicêntricos como Assunto , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Estudos Prospectivos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Neoplasias do Colo do Útero/patologia , Adulto JovemRESUMO
A one-step immunoassay was developed for five types of food-poisoning-related bacteria using a switching peptide and antibodies isolated from unimmunized horse serum. The one-step immunoassay involves mixing samples and reagents in a homogeneous solution without any washing steps. In this work, a one-step immunoassay configuration was developed using isolated antibodies labelled with an organic fluorescence quencher and a switching-peptide labelled with a fluorescent dye. The fluorescence-labelled switching-peptide was bound to the antigen-binding site of the isolated antibodies before binding to the bacteria (no fluorescence signal), and the switching-peptide dissociated from the antibodies as soon as they bound to the bacteria (fluorescence signal turns on). By quantifying the generated fluorescence signal, the one-step immunoassay presented here allows microbial detection without any washing step.
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Anticorpos , Transferência Ressonante de Energia de Fluorescência , Imunoensaio , Anticorpos/química , Peptídeos/química , BactériasRESUMO
Electronic devices composed of semiconducting two-dimensional (2D) materials and ultrathin 2D metallic electrode materials, accompanying synergistic interactions and extraordinary properties, are becoming highly promising for future flexible and transparent electronic and optoelectronic device applications. Unlike devices with bulk metal electrode and 2D channel materials, devices with ultrathin 2D electrode and 2D channel are susceptible to chemical reactions in both channel and electrode surface due to the high surface to volume ratio of the 2D structures. However, so far, the effect of doping was primary concerned on the channel component, and there is lack of understanding in terms of how to modulate electrical properties of devices by engineering electrical properties of both the metallic electrode and the semiconducting channel. Here, we propose the novel, one-pot doping of the field-effect transistor (FET) based on 2D molybdenum disulfide (MoS2) channel and ultrathin copper sulfide (CuS) electrodes under mild iodine gas environment at room temperature, which simultaneously modulates electrical properties of the 2D MoS2channel and 2D CuS electrode in a facile and cost-effective way. After one-pot iodine doping, effective p-type doping of the channel and electrode was observed, which was shown through decreased off current level, improvedIon/Ioffratio and subthreshold swing value. Our results open up possibility for effectively and conveniently modulating electrical properties of FETs made of various 2D semiconductors and ultrathin contact materials without causing any detrimental damage.
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PURPOSE: Peroxidation and reduction of 11S- and 13S-positions on C20 and C22 polyunsaturated fatty acids (PUFAs) by Escherichia coli expressing highly active arachidonate (ARA) 11S-lipoxygenase (11S-LOX) from Enhygromyxa salina with the reducing agent cysteine. RESULTS: The specific activity and catalytic efficiency of ARA 11S-LOX from E. salina were 4.1- and 91-fold higher than those of only reported ARA 11S-LOX from Myxococcus xanthus, respectively. The hydroxy fatty acids (HFAs) obtained by the biotransformation of ARA, eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexanoic acid (DHA) by Escherichia coli expressing 11S-LOX from E. salina in the presence of cysteine were identified as 11S-hydroxyeicosatetraenoic acid (11S-HETE), 11S-hydroxyeicosapentaenoic acid (11S-HEPE), 13S-hydroxydocosapentaenoic acid (13S-HDPA), and 13S-hydroxydocosahexaenoic acid (13S-HDHA), respectively. The recombinant cells converted 3 mM of ARA, EPA, DPA, and DHA into 2.9 mM of 11S-HETE, 2.4 mM 11S-HEPE, 1. 9 mM 13S-HDPA, and 2.2 mM 13S-HDHA in 60, 80, 120, and 120 min, corresponding to productivities of 72.5, 40.4, 18.5, and 22.4 µM min-1 and conversion yields of 96.7, 80.0, 62.3, and 74.6%, respectively. CONCLUSIONS: We report the highest concentrations, conversion yields, and productivities of 11S- and 13S-hydroxy fatty acids from C20- and C22-PUFAs achieved via E. coli expressing highly active E. salina 11S-LOX.
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Escherichia coli , Lipoxigenase , Araquidonato Lipoxigenases/metabolismo , Biotransformação , Cisteína/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ácidos Graxos , Ácidos Graxos Insaturados/metabolismo , Ácidos Hidroxieicosatetraenoicos , Lipoxigenase/metabolismo , MyxococcalesRESUMO
BACKGROUND: To deliver therapeutics into the brain, it is imperative to overcome the issue of the blood-brain-barrier (BBB). One of the ways to circumvent the BBB is to administer therapeutics directly into the brain parenchyma. To enhance the treatment efficacy for chronic neurodegenerative disorders, repeated administration to the target location is required. However, this increases the number of operations that must be performed. In this study, we developed the IntraBrain Injector (IBI), a new implantable device to repeatedly deliver therapeutics into the brain parenchyma. METHODS: We designed and fabricated IBI with medical grade materials, and evaluated the efficacy and safety of IBI in 9 beagles. The trajectory of IBI to the hippocampus was simulated prior to surgery and the device was implanted using 3D-printed adaptor and surgical guides. Ferumoxytol-labeled mesenchymal stem cells (MSCs) were injected into the hippocampus via IBI, and magnetic resonance images were taken before and after the administration to analyze the accuracy of repeated injection. RESULTS: We compared the planned vs. insertion trajectory of IBI to the hippocampus. With a similarity of 0.990 ± 0.001 (mean ± standard deviation), precise targeting of IBI was confirmed by comparing planned vs. insertion trajectories of IBI. Multiple administrations of ferumoxytol-labeled MSCs into the hippocampus using IBI were both feasible and successful (success rate of 76.7%). Safety of initial IBI implantation, repeated administration of therapeutics, and long-term implantation have all been evaluated in this study. CONCLUSION: Precise and repeated delivery of therapeutics into the brain parenchyma can be done without performing additional surgeries via IBI implantation.
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Óxido Ferroso-Férrico , Células-Tronco Mesenquimais , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Cães , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodosRESUMO
The trade-off between thermal conductivity (κ) and thermal contact resistance (Rc ) is regarded as a hurdle to develop superior interface materials for thermal management. Here a high-temperature skin softening material to overcome the trade-off relationship, realizing a record-high total thermal conductance (254.92 mW mm-2 K-1 ) for isotropic pad-type interface materials is introduced. A highly conductive hard core is constructed by incorporating Ag flakes and silver nanoparticle-decorated multiwalled carbon nanotubes in thermosetting epoxy (EP). The thin soft skin is composed of filler-embedded thermoplastic poly(ethylene-co-vinyl acetate) (PEVA). The κ (82.8 W m-1 K-1 ) of the PEVA-EP-PEVA interface material is only slightly compromised, compared with that (106.5 W m-1 K-1 ) of the EP core (386 µm). However, the elastic modulus (E = 2.10 GPa) at the skin is significantly smaller than the EP (26.28 GPa), enhancing conformality and decreasing Rc from 108.41 to 78.73 mm2 K W-1 . The thermoplastic skin is further softened at an elevated temperature (100 °C), dramatically decreasing E (0.19 GPa) and Rc (0.17 mm2 K W-1 ) with little change in κ, overcoming the trade-off relationship and enhancing the total thermal conductance by 2030%. The successful heat dissipation and applicability to the continuous manufacturing process demonstrate excellent feasibility as future thermal management materials.
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Nanopartículas Metálicas , Nanotubos de Carbono , Temperatura Alta , Prata , Temperatura , Condutividade TérmicaRESUMO
Leukotrienes (LTs) and maresins (MaRs) are human lipid mediators (LMs) involved in immune response and anti-inflammation, respectively. These compounds and their isomers are generated in trace amounts by lipoxygenases (LOXs) in human macrophages and neutrophils. These LMs have been synthesized using nonenvironmentally benign synthetic protocols, which are expensive. 8S- and 15S-LOXs with double dioxygenating activities have previously been reported, whereas 12S-LOX with double dioxygenating activity have not been reported to date. Here, we discovered a wild-type 12S-LOX with double dioxygenating activity from the bacterium Endozoicomonas numazuensis, which produced dihydroxy fatty acids (DiHFAs) as LMs from polyunsaturated fatty acids via double dioxygenation. The enzyme activity for producing DiHFA was approximately 550-fold higher than that of mammalian LOX with double dioxygenating activity. The microbial 12S-LOX converted 3.00 mM of arachidonic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid to 2.37 mM (797 mg/L) 6-trans-8-cis-12S-epimer of LTB4, 1.59 mM (532 mg/L) 6-trans-8-cis-12S-epimer of LTB5, 1.35 mM (498 mg/L) 10-cis-12-trans-7S-epimer of MaR1n-3 DPA , and 1.54 mM (555 mg/L) 10-cis-12-trans-7S-epimer of MaR1 within 2 h, which were 5.3-, 7.6-, 3.1-, and 5.5-fold higher than those biosynthesized by the previously reported microbial engineered 12S-LOX with double dioxygenating activity, respectively. These findings contribute to the efficient and environmentally friendly biosynthesis of LMs and stimulate physiological study on LMs.