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Cullin-RING ubiquitin ligase 4 (CRL4) is closely correlated with the incidence and progression of ovarian cancer. DDB1- and CUL4-associated factor 13 (DCAF13), a substrate-recognition protein in the CRL4 E3 ubiquitin ligase complex, is involved in the occurrence and development of ovarian cancer. However, its precise function and the underlying molecular mechanism in this disease remain unclear. In this study, we confirmed that DCAF13 is highly expressed in human ovarian cancer and its expression is negatively correlated with the overall survival rate of patients with ovarian cancer. We then used CRISPR/Cas9 to knockout DCAF13 and found that its deletion significantly inhibited the proliferation, colony formation, and migration of human ovarian cancer cells. In addition, DCAF13 deficiency inhibited tumor proliferation in nude mice. Mechanistically, CRL4-DCAF13 targeted Fraser extracellular matrix complex subunit 1 (FRAS1) for polyubiquitination and proteasomal degradation. FRAS1 influenced the proliferation and migration of ovarian cancer cell through induction of the focal adhesion kinase (FAK) signaling pathway. These findings collectively show that DCAF13 is an important oncogene that promotes tumorigenesis in ovarian cancer cells by mediating FRAS1/FAK signaling. Our findings provide a foundation for the development of targeted therapeutics for ovarian cancer.
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Movimiento Celular , Proliferación Celular , Proteínas de la Matriz Extracelular , Quinasa 1 de Adhesión Focal , Ratones Desnudos , Neoplasias Ováricas , Proteínas de Unión al ARN , Animales , Femenino , Humanos , Ratones , Línea Celular Tumoral , Movimiento Celular/genética , Progresión de la Enfermedad , Quinasa 1 de Adhesión Focal/metabolismo , Quinasa 1 de Adhesión Focal/genética , Regulación Neoplásica de la Expresión Génica , Ratones Endogámicos BALB C , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/genética , Transducción de Señal , Ubiquitinación , Proteínas de Unión al ARN/metabolismo , Proteínas de la Matriz Extracelular/metabolismoRESUMEN
Recently, the rising demand for data-based applications has driven the convergence of image sensing, memory, and computing unit interfaces. While specialized electronic hardware has spurred advancements in the in-memory and in-sensor computing, integrating the entire signal-processing chain into a single device still faces significant challenges. Here, a reconfigurable all-optical controlled memristor with the selector-free feature is demonstrated. The conductance of the device can be controlled within the pure light domain, which enables it to integrate sensing, memory, and computing together. The integrate-and-fire behavior is also realized through electrical stimuli. Furthermore, the device exhibits an excellent rectifying ratio and nonlinearity to overcome the sneak current. Finally, an in-memory sensing and computing architecture is realized through reservoir computing based on neuron and synaptic functions mimicked by the proposed device. Such an all-in-one paradigm facilitates the computing architecture with low energy consumption, low latency, and reduced hardware complexity.
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Functionally diverse devices with artificial neuron and synapse properties are critical for neuromorphic systems. We present a two-terminal artificial leaky-integrate-fire (LIF) neuron based on 6 nm Hf0.1Zr0.9O2 (HZO) antiferroelectric (AFE) thin films and develop a synaptic device through work function (WF) engineering. LIF neuron characteristics, including integration, firing, and leakage, are achieved in W/HZO/W devices due to the accumulated polarization and spontaneous depolarization of AFE HZO films. By engineering the top electrode with asymmetric WFs, we found that Au/Ti/HZO/W devices exhibit synaptic weight plasticity, such as paired-pulse facilitation and long-term potentiation/depression, achieving >90% accuracy in digit recognition within constructed artificial neural network systems. These findings suggest that AFE HZO capacitor-based neurons and WF-engineered artificial synapses hold promise for constructing efficient spiking neuron networks and artificial neural networks, thereby advancing neuromorphic computing applications based on emerging AFE HZO devices.
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The helper-like ILC contains various functional subsets, such as ILC1, ILC2, ILC3 and LTi cells, mediating the immune responses against viruses, parasites, and extracellular bacteria, respectively. Among them, LTi cells are also crucial for the formation of peripheral lymphoid tissues, such as lymph nodes. Our research, along with others', indicates a high proportion of LTi cells in the fetal ILC pool, which significantly decreases after birth. Conversely, the proportion of non-LTi ILCs increases postnatally, corresponding to the need for LTi cells to mediate lymphoid tissue formation during fetal stages and other ILC subsets to combat diverse pathogen infections postnatally. However, the regulatory mechanism for this transition remains unclear. In this study, we observed a preference for fetal ILC progenitors to differentiate into LTi cells, while postnatal bone marrow ILC progenitors preferentially differentiate into non-LTi ILCs. Particularly, this differentiation shift occurs within the first week after birth in mice. Further analysis revealed that adult ILC progenitors exhibit stronger activation of the Notch signaling pathway compared to fetal counterparts, accompanied by elevated Gata3 expression and decreased Rorc expression, leading to a transition from fetal LTi cell-dominant states to adult non-LTi ILC-dominant states. This study suggests that the body can regulate ILC development by modulating the activation level of the Notch signaling pathway, thereby acquiring different ILC subsets to accommodate the varying demands within the body at different developmental stages.
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BACKGROUND: Klebsiella pneumoniae (KP) is the second most prevalent Gram-negative bacterium causing bloodstream infections (BSIs). In recent years, the management of BSIs caused by KP has become increasingly complex due to the emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP). Although numerous studies have explored the risk factors for the development of CRKP-BSIs, the mortality of patients with KP-BSIs, and the molecular epidemiological characteristics of CRKP, the variability in data across different populations, countries, and hospitals has led to inconsistent conclusions. In this single-center retrospective observational study, we utilized logistic regression analyses to identify independent risk factors for CRKP-BSIs and factors associated with mortality in KP-BSI patients. Furthermore, a risk factor-based prediction model was developed. CRKP isolates underwent whole-genome sequencing (WGS), followed by an evaluation of microbiological characteristics, including antimicrobial resistance and virulence genes, as well as epidemiological characteristics and phylogenetic analysis. RESULTS: Our study included a total of 134 patients with KP-BSIs, comprising 50 individuals infected with CRKP and 84 with carbapenem-susceptible Klebsiella pneumoniae (CSKP). The independent risk factors for CRKP-BSIs were identified as gastric catheterization (OR = 9.143; CI = 1.357-61.618; P = 0.023), prior ICU hospitalization (OR = 4.642; CI = 1.312-16.422; P = 0.017), and detection of CRKP in non-blood sites (OR = 8.112; CI = 2.130-30.894; P = 0.002). Multivariate analysis revealed that microbiologic eradication after 6 days (OR = 3.569; CI = 1.119-11.387; P = 0.032), high Pitt bacteremia score (OR = 1.609; CI = 1.226-2.111; P = 0.001), and inappropriate empirical treatment after BSIs (OR = 6.756; CI = 1.922-23.753; P = 0.003) were independent risk factors for the 28-day mortality in KP-BSIs. The prediction model confirmed that microbiologic eradication after 6.5 days and a Pitt bacteremia score of 4.5 or higher were significant predictors of the 28-day mortality. Bioinformatics analysis identified ST11 as the predominant CRKP sequence type, with blaKPC-2 as the most prevalent gene variant. CRKP stains carried multiple plasmid-mediated resistance genes along with some virulence genes. Phylogenetic analysis indicated the presence of nosocomial transmission of ST11 CRKP within the ICU. CONCLUSIONS: The analysis of risk factors for developing CRKP-BSIs and the association between KP-BSIs and 28-day mortality, along with the development of a risk factor-based prediction model and the characterization of CRKP strains, enhances clinicians' understanding of the pathogens responsible for BSIs. This understanding may help in the timely administration of antibiotic therapy for patients with suspected KP-BSIs, potentially improving outcomes.
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Antibacterianos , Bacteriemia , Carbapenémicos , Infecciones por Klebsiella , Klebsiella pneumoniae , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/aislamiento & purificación , Estudios Retrospectivos , Infecciones por Klebsiella/microbiología , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/mortalidad , Infecciones por Klebsiella/tratamiento farmacológico , Factores de Riesgo , Masculino , Femenino , Persona de Mediana Edad , Anciano , Bacteriemia/microbiología , Bacteriemia/mortalidad , Bacteriemia/epidemiología , Bacteriemia/tratamiento farmacológico , Antibacterianos/farmacología , Carbapenémicos/farmacología , Filogenia , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del Genoma , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Factores de Virulencia/genética , Anciano de 80 o más Años , AdultoRESUMEN
High dielectric constant (k) polymers have been widely explored for flexible, low-power-consumption electronic devices. In this work, solution-processable high-k polymers were designed and synthesized by ultraviolet (UV) triggered crosslinking at a low temperature (60 °C). The highly crosslinked network allows for high resistance to organic solvents and high breakdown strength over 2 MV cm-1. The UV-crosslinking capability of the polymers enables them to achieve a high-resolution pattern with a feature size down to 1 µm. Further investigation suggests that the polar cyano pendants in side chains are responsible for increasing the dielectric constant up to 10 in a large-area device array, thereby contributing to a low driving voltage of 5 V and high field-effect mobility exceeding 20 cm2 V-1 s-1 in indium gallium zinc oxide (IGZO) thin-film transistors (TFTs). In addition, the solution-processable high-k dielectric polymers were utilized to fabricate flexible low-voltage organic TFTs, which show highly reliable and reproducible mechanical stability at a bending radius of 5 mm after 1000 cycles. And also, the high radiation stability of the dielectric polymers was observed in a UV-sensitive TFT device, thereby achieving highly reproducible pattern recognition, which is promising for artificial optic nerve circuits.
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Climate change and human interference, notably nutrient input, affect the water quality. Nitrogen (N) and phosphorus (P) are pivotal in managing eutrophication. This study investigated the effects of water dynamics and chemical constituents on water quality in Hongfeng Lake, a typical weakly stratified reservoir suffering from algae blooms in Southwest China, using the Environmental Fluid Dynamics Code. Leveraging climate, hydrological, and water quality data, we constructed, calibrated, and validated the temperature-hydrodynamics-water quality-sediment model. Various scenarios were analyzed, including wind speed, air temperature, solar radiation, rainfall, water discharge, N and P external input, and internal release. The findings revealed that no rain and warming increased trophic state index (TSI) and chlorophyll-a (Chl-a) concentration, and no solar radiation initially elevated nitrate concentration, followed by an increase in ammonium concentration. Besides, no solar radiation and changes in rainfall significantly increased total phosphate concentration. The management scenarios of N and P reduction, halving tributary, and mainstream flow scenarios improved water quality and reduced eutrophication. The wind speed under the N and P reduced scenarios showed that a doubling in wind led to increased concentrations of the particulate organic matter, Chl-a, and dissolved oxygen, alongside decreased ammonium and nitrate, while TSI exhibited minimal change. However, 5- and 10-times wind speed scenarios amplified TSI in shallow water, potentially due to a substantial rise in internal nutrient release. The degradation trend observed in drinking water quality amid climate change (warming and flooding) raises concerns regarding health-related risks. These simulations provided the quantified influence of climate change and environmental management strategies on water quality in the weakly stratified reservoir, notably highlighting the looming threat of exacerbated eutrophication due to warming, necessitating more stringent N and P reduction measures compared to current practices.
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This study conducted a comprehensive analysis of trace element concentrations in the Upper Indus River Basin (UIRB), a glacier-fed region in the Western Himalayas (WH), aiming to discern their environmental and anthropogenic sources and implications. Despite limited prior data, 69 samples were collected in 2019 from diverse sources within the UIRB, including mainstream, tributaries, and groundwater, to assess trace element concentrations. Enrichment factor (EF) results and comparisons with regional and global averages suggest that rising levels of Zn, Cd, and As may pose safety concerns for drinking water quality. Advanced multivariate statistical techniques such as principal component analysis (PCA), absolute principal component scores (APCS-MLR), Monte Carlo simulation (MCS), etc were applied to estimate the associated human health hazards and also identified key sources of trace elements. The 95th percentile of the MCS results indicates that the estimated total cancer risk for children is significantly greater than (>1000 times) the USEPA's acceptable risk threshold of 1.0 × 10-6. The results classified most of the trace elements into two distinct groups: Group A (Li, Rb, Sr, U, Cs, V, Ni, TI, Sb, Mo, Ge), linked to geogenic sources, showed lower concentrations in the lower-middle river reaches, including tributaries and downstream regions. Group B (Pb, Nb, Cr, Zn, Be, Al, Th, Ga, Cu, Co), influenced by both geogenic and anthropogenic activities, exhibited higher concentrations near urban centers and midstream areas, aligning with increased municipal waste and agricultural activities. Furthermore, APCS-MLR source apportionment indicated that trace elements originated from natural geogenic processes, including rock-water interactions and mineral dissolution, as well as anthropogenic activities. These findings underscore the need for targeted measures to mitigate anthropogenic impacts and safeguard water resources for communities along the IRB and WH.
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The piezoelectric properties of two-dimensional semiconductor nanobubbles present remarkable potential for application in flexible optoelectronic devices, and the piezoelectric field has emerged as an efficacious pathway for both the separation and migration of photogenerated electron-hole pairs, along with inhibition of recombination. However, the comprehension and control of photogenerated carrier dynamics within nanobubbles still remain inadequate. Hence, this study is dedicated to underscore the importance of in situ detection and detailed characterization of photogenerated electron-hole pairs in nanobubbles to enrich understanding and strategic manipulation in two-dimensional semiconductor materials. Utilizing frequency modulation kelvin probe force microscopy (FM-KPFM) and strain gradient distribution techniques, the existence of a piezoelectric field in monolayer WS2 nanobubbles was confirmed. Combining w/o and with illumination FM-KPFM, second-order capacitance gradient technique and in situ nanoscale tip-enhanced photoluminescence characterization techniques, the interrelationships among the piezoelectric effect, interlayer carrier transfer, and the funneling effect for photocarrier dynamics process across various nanobubble sizes were revealed. Notably, for a WS2/graphene bubble height of 15.45 nm, a 0 mV surface potential difference was recorded in the bubble region w/o and with illumination, indicating a mutual offset of piezoelectric effect, interlayer carrier transfer, and the funneling effect. This phenomenon is prevalent in transition metal dichalcogenides materials exhibiting inversion symmetry breaking. The implication of our study is profound for advancing the understanding of the dynamics of photogenerated electron-hole pair in nonuniform strain piezoelectric systems, and offers a reliable framework for the separation and modulation of photogenerated electron-hole pair in flexible optoelectronic devices and photocatalytic applications.
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Purpose: This study aimed to evaluate nocturnal sleep structure and anxiety, depression, and fatigue in patients with narcolepsy type 1 (NT1). Methods: Thirty NT1 patients and thirty-five healthy controls were enrolled and evaluated using the Epworth sleepiness scale (ESS), Generalized Anxiety Disorder-7, Patient Health Questionnaire-9, Fatigue Severity Scale (FSS), polysomnography, multiple sleep latency test, and brain function state monitoring. Statistical analyses were performed using SPSS Statistics for Windows, version 23.0. Benjamini-Hochberg correction was performed to control the false discovery rate. Results: Apart from typical clinical manifestations, patients with NT1 are prone to comorbidities such as nocturnal sleep disorders, anxiety, depression, and fatigue. Compared with the control group, patients with NT1 exhibited abnormal sleep structure, including increased total sleep time (P adj=0.007), decreased sleep efficiency (P adj=0.002), shortening of sleep onset latency (P adj<0.001), elevated wake after sleep onset (P adj=0.002), increased N1% (P adj=0.006), and reduced N2%, N3%, and REM% (P adj=0.007, P adj<0.001, P adj=0.013). Thirty-seven percent of patients had moderate to severe obstructive sleep apnea-hypopnea syndrome. And sixty percent of patients were complicated with REM sleep without atonia. Patients with NT1 displayed increased anxiety propensity (P adj<0.001), and increased brain fatigue (P adj=0.020) in brain function state monitoring. FSS scores were positively correlated with brain fatigue (P adj<0.001) and mean sleep latency was inversely correlated with FSS scores and brain fatigue (P adj=0.013, P adj=0.029). Additionally, ESS scores and brain fatigue decreased after 3 months of therapy (P=0.012, P=0.030). Conclusion: NT1 patients had abnormal nocturnal sleep structures, who showed increased anxiety, depression, and fatigue. Excessive daytime sleepiness and fatigue improved after 3 months of treatment with methylphenidate hydrochloride prolonged-release tablets in combination with venlafaxine.
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The integrated smart electronics for real-time monitoring and personalized therapy of disease-related analytes have been gradually gaining tremendous attention. However, human tissue barriers, including the skin barrier and brain-blood barrier, pose significant challenges for effective biomarker detection and drug delivery. Microneedle (MN) electronics present a promising solution to overcome these tissue barriers due to their semi-invasive structures, enabling effective drug delivery and target-analyte detection without compromising the tissue configuration. Furthermore, MNs can be fabricated through solution processing, facilitating large-scale manufacturing. This review provides a comprehensive summary of the recent three-year advancements in smart MNs development, categorized as follows. First, the solution-processed technology for MNs is introduced, with a focus on various printing technologies. Subsequently, smart MNs designed for sensing, drug delivery, and integrated systems combining diagnosis and treatment are separately summarized. Finally, the prospective and promising applications of next-generation MNs within mediated diagnosis and treatment systems are discussed.
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Técnicas Biosensibles , Sistemas de Liberación de Medicamentos , Diseño de Equipo , Agujas , Dispositivos Electrónicos Vestibles , Humanos , Técnicas Biosensibles/instrumentación , Sistemas de Liberación de Medicamentos/instrumentación , Electrónica/instrumentaciónRESUMEN
The carbon generalized system of preferences (CGSP) is an innovative incentive mechanism implemented by the Chinese government, which has also become an important part of carbon emission reduction at the living end, and it is of great significance to study whether the Pilot Policy can reduce the carbon emissions of residents. This study firstly accounts for the total carbon emissions and per capita carbon emissions of the residents of 284 cities in China, and on this basis, adopts the SCM method to quantitatively study and analyze the overall and local implementation effects of CGSP in China by taking the first batch of CGSP pilots in China as an example, and further applies the mediation effect model to test the pathways of the role of CGSP. The main findings of the study are as follows: (1) During the period of 2010-2020, the total carbon emissions from urban residents' living in China showed a yearly growth trend, from 36,623.98 ×10-2Mt in 2010-85,241.20 ×10-2Mt in 2020, an increase of 8.83%. Total carbon emissions present a structural difference of "electricity consumption > central heating > private transport > gas (oil, natural gas) consumption". (2) Overall, the implementation of the CGSP had a robust positive impact on the overall carbon emission reduction in the pilot cities, with an average annual emission reduction effect value of 36.53 ×10-2Mt. Locally, the annual net policy effect values of Dongguan, Zhongshan, Heyuan, and Guangzhou are 6169.79 ×10-2, 26,600.17 ×10-2, 17,081.34 ×10-2 and 9393.36 ×10-2Mt respectively. (3) CGSP has a good carbon emission reduction effect by suppressing the impact on residents' carbon emissions through enhancing the city's innovation capacity and promoting electricity saving and consumption reduction, while the mediating effect played by the promotion of green and low-carbon travel in the pilot policy is not significant. Finally, based on the research findings, relevant suggestions are targeted.
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Carbono , Ciudades , China , Humanos , Contaminación del Aire/prevención & control , Dióxido de Carbono/análisisRESUMEN
A novel high-speed and process-compatible carrier-stored trench-gate bipolar transistor (CSTBT) combined with split-gate technology is proposed in this paper. The device features a split polysilicon electrode in the trench, where the left portion is equipotential with the cathode. This design mitigates the impact of the anode on the trench gate, resulting in a reduction in the gate-collector capacitance (CGC) to improve the dynamic characteristics. On the left side of the device cell, the P-layer, the carrier-stored (CS) layer and the P-body are formed from the bottom up by ion implantation and annealing. The P-layer beneath the trench bottom can decrease the electric field at the bottom of the trench, thereby improving breakdown voltage (BV) performance. Simultaneously, the highly doped CS layer strengthens the hole-accumulation effect at the cathode. Moreover, the PNP doping layers on the left form a self-biased pMOS. In a short-circuit state, the self-biased pMOS turns on at a certain collector voltage, causing the potential of the CS-layer to be clamped by the hole channel. Consequently, the short-circuit current no longer increases with the collector voltage. The simulation results reveal significant improvements in comparison with the conventional CSTBT under the same on-state voltage (1.48 V for 100 A/cm2). Specifically, the turn-off time (toff) and turn-off loss (Eoff) are reduced by 38.4% and 41.8%, respectively. The short-circuit current is decreased by 50%, while the short-circuit time of the device is increased by 2.46 times.
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Understanding the interaction between metal ions as catalytic centers and supramolecular scaffolds as chiral substrates plays an important role in developing chiral supramolecular catalysts with high enantioselectivity. Herein, we found that compared with l-norleucine chiral amphiphile (l-NorC16), l-methionine chiral amphiphile (l-MetC16) with the only heteroatom of S site difference in the hydrophilic group can form a similar supramolecular chiral nanoribbon (NR) with the bilayer structure through the self-assembly approach; yet, the interaction between the Cu(II) ion catalytic centers and supramolecular scaffolds is reinforced, favoring the chirality transfer and therefore enhancing their catalytic enantioselectivity of Diels-Alder reaction from 23% [l-NorC16-NR-Cu(II)] to 78% [l-MetC16-NR-Cu(II)]. Our work demonstrates a new strategy from the perspective of strengthening the metal ion-supramolecular scaffold interaction for the preparation of chiral supramolecular catalysts with good catalytic enantioselectivity.
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Background: Restless legs syndrome (RLS) is a prevalent sensorimotor nervous system disorder in patients accompanied with insomnia, blood pressure fluctuation, and sympathetic dysfunction. These symptoms may disrupt cerebral hemodynamics. Dynamic cerebral autoregulation (dCA) describes the temporary response of cerebrovascular system to abrupt fluctuations in blood pressure, which keep cerebral blood flow stable and serve as a marker of cerebrovascular system ability. Objective: This research aimed to assess dCA in RLS patients. Methods: In this study, RLS patients were recruited and subsequently classified into four groups (mild, moderate, severe, and very severe) based on the International RLS Rating Scale (IRLS). Healthy controls matched for age and sex were enrolled. All participants were evaluated dCA by assessing phase difference (PD). A portion of patients with RLS was reassessed for dCA after one month of medication therapy (pramipexole [0.125 mg/day] and gabapentin [300 mg/day]). Results: There were altogether 120 patients with RLS and 30 controls completed the polysomnography and dCA assessment. PD was lower in the moderate, severe, and very severe RLS groups than that in the controls and mild RLS groups. Periodic limb movement index (PLMI), arousal index, and IRLS all showed a linear correlation with PD in RLS patients. Additionally, PD increased in RLS patients after therapy. Conclusion: The dCA was compromised in moderate, severe, and very severe RLS patients and was negatively correlated with the IRLS, arousal index, and PLMI. After 1 month of therapy, dCA improved in RLS patients.
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The ability to control the catalytic activity of enzymes in chemical transformations is essential for the design and development of artificial catalysts. Herein, we report the synthesis and characterization of functional ligands featuring two 1,4,7,10-tetraazacyclododecane units linked by an azobenzene group and their corresponding dinuclear Zn(II) complexes. We show that the configuration switching (E/Z) of the azobenzene spacer in the ligands and their dinuclear Zn(II) complexes is reversibly controlled by irradiation with UV and visible light. The Zn(II)-metal complexes are light-responsive catalysts for the hydrolytic cleavage of nerve agent simulants, i.e., p-nitrophenyl diphenyl phosphate and methyl paraoxon. The catalytic activity of the Z-isomers of the dinuclear Zn(II) complexes outperformed that of the E-counterparts. Moreover, combining the less active E-isomers with gold nanoparticles induced an enhancement in the hydrolysis rate of p-nitrophenyl diphenyl phosphate. Kinetic analysis has shown that the catalytic site appears to involve a single metal ion. We explain our results by considering the different desolvation effects occurring in the catalyst's configurations in the solution and the catalytic systems involving gold nanoparticles.
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Understanding the structure-function relationships encoded on chiral catalysts is important for investigating the fundamental principles of catalytic enantioselectivity. Herein, the synthesis and self-assembly of naphthalene substituted bis-l/d-histidine amphiphiles (bis-l/d-NapHis) in DMF/water solution mixture is reported. The resulting supramolecular assemblies featuring well-defined P/M nanoribbons (NRs). With combination of the (P/M)-NR and metal ion catalytic centers (Mn+ = Co2+, Cu2+, Fe3+), the (P)-NR-Mn+ as chiral supramolecular catalysts show catalytic preference to 3,4-dihydroxy-S-phenylalanine (S-DOPA) oxidation while the (M)-NR-Mn+ show enantioselective bias to R-DOPA oxidation. In contrast, their monomeric counterparts bis-l/d-NapHis-Mn+ display an inverse and dramatically lower catalytic selectivity in the R/S-DOPA oxidation. Among them, the Co2+-coordinated supramolecular nanostructures show the highest catalytic efficiency and enantioselectivity (select factor up to 2.70), while the Fe3+-coordinated monomeric ones show nearly racemic products. Analysis of the kinetic results suggests that the synergistic effect between metal ions and the chiral supramolecular NRs can significantly regulate the enantioselective catalytic activity, while the metal ion-mediated monomeric bis-l/d-NapHis were less active. The studies on association constants and activation energies reveal the difference in catalytic efficiency and enantioselectivity resulting from the different energy barriers and binding affinities existed between the chiral molecular/supramolecular structures and R/S-DOPA enantiomers. This work clarifies the correlation between chiral molecular/supramolecular structures and enantioselective catalytic activity, shedding new light on the rational design of chiral catalysts with outstanding enantioselectivity.
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L/D-Phenylglycine amphiphiles and metal ions with peroxidase-like activity self-assembled into chiral nanoribbons, which act as efficient chiral supramolecular nanozymes for catalyzing the 3,4-dihydroxy-L/D-phenylalanine (L/D-DOPA) oxidation reactions. The catalytic efficiency and enantioselectivity are dominated by the chirality transfer and the synergistic effect between the metal ions and chiral nanoribbons.
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Innate immune response is the first line of defense for the host against virus invasion. One important response is the synthesis and secretion of type I interferon (IFN-I) in the virus-infected host cells. Here, we found that respiratory syncytial virus (RSV) infection induced high expression of TRIM25, which belongs to the tripartite motif-containing (TRIM) family of proteins. TRIM25 bound and activated retinoic acid-inducible gene I (RIG-I) by K63-linked ubiquitination. Accordingly, RIG-I mediated the production of IFN-I mainly through the nuclear factor kappa-B (NF-κB) pathway in respiratory epithelial cells. Interestingly, IFN-I, in turn, promoted a high expression of TRIM38 which downregulated the expression of IFN-I by reducing the protein level of RIG-I by K48-linked ubiquitination. More importantly, the binding site of TRIM25 to RIG-I was found in the narrow 25th-43rd amino acid (aa) region of RIG-I N-terminus. In contrast, the binding sites of TRIM38 to RIG-I were found in a much wider amino acid region, which included the binding site of TRIM25 on RIG-I. As a result, TRIM38 inhibits the production of IFN-I by competing with TRIM25 for RIG-I binding. Thus, TRIM38 negatively regulates RIG-I activation to, in turn, downregulate IFN-I expression, thus interfering with host immune response. A negative feedback loop effectively "puts the brakes" on the reaction once host immune response is overactivated and homeostasis is unbalanced. We also discovered that TRIM25 bound RIG-I by a new K63-linked ubiquitination located at K-45 of the first caspase recruitment domain (CARD). Collectively, these results confirm an antagonism between TRIM38 and TRIM25 in regulating IFN-I production by affecting RIG-I activity following RNA virus infection.
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Proteína 58 DEAD Box , Regulación hacia Abajo , Interferón Tipo I , Receptores Inmunológicos , Factores de Transcripción , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas , Ubiquitinación , Proteínas de Motivos Tripartitos/metabolismo , Proteína 58 DEAD Box/metabolismo , Humanos , Ubiquitina-Proteína Ligasas/metabolismo , Interferón Tipo I/metabolismo , Interferón Tipo I/biosíntesis , Factores de Transcripción/metabolismo , Receptores Inmunológicos/metabolismo , Infecciones por Virus Sincitial Respiratorio/inmunología , Infecciones por Virus Sincitial Respiratorio/metabolismo , Infecciones por Virus Sincitial Respiratorio/virología , Unión Proteica , Células A549 , Virus Sincitiales Respiratorios/inmunologíaRESUMEN
With the development of wearable devices and hafnium-based ferroelectrics (FE), there is an increasing demand for high-performance flexible ferroelectric memories. However, developing ferroelectric memories that simultaneously exhibit good flexibility and significant performance has proven challenging. Here, we developed a high-performance flexible field-effect transistor (FeFET) device with a thermal budget of less than 400 °C by integrating Zr-doped HfO2 (HZO) and ultra-thin indium tin oxide (ITO). The proposed FeFET has a large memory window (MW) of 2.78 V, a high current on/off ratio (ION/IOFF) of over 108, and high endurance up to 2×107 cycles. In addition, the FeFETs under different bending conditions exhibit excellent neuromorphic properties. The device exhibits excellent bending reliability over 5×105 pulse cycles at a bending radius of 5 mm. The efficient integration of hafnium-based ferroelectric materials with promising ultrathin channel materials (ITO) offers unique opportunities to enable high-performance back-end-of-line (BEOL) compatible wearable FeFETs for edge intelligence applications.