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ABSTRACT: This study explored the path affecting the quality of life (QOL) of people with HIV in China and clarified the applicability and interpretability of the Self-Regulatory HIV/AIDS Symptom Management Model. We conducted a cross-sectional survey in nine regions of China and collected information about demographics, symptom experience, social support, perceived symptom manageability, self-efficacy, and QOL. A total of 711 patients participated in this survey. After four rounds of path analysis were conducted, the most fit indices met the standards (χ 2 /df = 2.633, Root Mean Square Error of Approximation = 0.081, Goodness-of-Fit Index/Adjusted Goodness-of-Fit Index/Comparative Fit Index/Incremental Fit Index/Tucker-Lewis Coefficient > 0.9), and the relationships between variables were statistically significant ( p < .05). Among all the pathways, social support had the most significant impact on the QOL, with a total path coefficient of 0.665. Symptom experience, as a negative factor, had a total effect value of -0.361. This study showed how all the factors influencing QOL were interconnected, serving as a crucial theoretical foundation for intervention strategies in future clinical practice.
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The highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) poses a significant threat to the global swine industry. Vaccination is a preventive measure against viral infections. However, the use of vaccines in livestock healthcare programs faces the challenge of safety and delayed immune responses. Earlier studies have shown the potential of modified Bazhen powder as an immunomodulator with significant biological properties, but its effect on vaccines against HP-PRRSV is yet to be studied. This study elucidated how modified Bazhen powder could improve the safety and efficacy of the conventional PRRSV vaccine by evaluating T-cell responses, antibody levels, clinical symptoms, levels of viremia, organ health, and cytokine production. The results revealed that the oral application of modified Bazhen powder in combination with PRRS vaccination improved both cellular and humoral immunity, accelerated viremia clearance, improved lung injury scores, and reduced viral load in the tonsils. The modified Bazhen powder also effectively reduced inflammatory responses following a PRRSV challenge. These findings further highlight the pharmacological properties of modified Bazhen powder as a potential oral immunomodulatory agent that could enhance vaccine efficacy and ensure broad-spectrum protection against HP-PRRSV in pigs.
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Background: Acute respiratory distress syndrome (ARDS) is a life-threatening condition with a high incidence and mortality rate in intensive care unit (ICU) admissions. Early identification of patients at high risk for developing ARDS is crucial for timely intervention and improved clinical outcomes. However, the complex pathophysiology of ARDS makes early prediction challenging. This study aimed to develop an artificial intelligence (AI) model for automated lung lesion segmentation and early prediction of ARDS to facilitate timely intervention in the intensive care unit. Methods: A total of 928 ICU patients with chest computed tomography (CT) scans were included from November 2018 to November 2021 at three centers in China. Patients were divided into a retrospective cohort for model development and internal validation, and three independent cohorts for external validation. A deep learning-based framework using the UNet Transformer (UNETR) model was developed to perform the segmentation of lung lesions and early prediction of ARDS. We employed various data augmentation techniques using the Medical Open Network for AI (MONAI) framework, enhancing the training sample diversity and improving the model's generalization capabilities. The performance of the deep learning-based framework was compared with a Densenet-based image classification network and evaluated in external and prospective validation cohorts. The segmentation performance was assessed using the Dice coefficient (DC), and the prediction performance was assessed using area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. The contributions of different features to ARDS prediction were visualized using Shapley Explanation Plots. This study was registered with the China Clinical Trial Registration Centre (ChiCTR2200058700). Findings: The segmentation task using the deep learning framework achieved a DC of 0.734 ± 0.137 in the validation set. For the prediction task, the deep learning-based framework achieved AUCs of 0.916 [0.858-0.961], 0.865 [0.774-0.945], 0.901 [0.835-0.955], and 0.876 [0.804-0.936] in the internal validation cohort, external validation cohort I, external validation cohort II, and prospective validation cohort, respectively. It outperformed the Densenet-based image classification network in terms of prediction accuracy. Moreover, the ARDS prediction model identified lung lesion features and clinical parameters such as C-reactive protein, albumin, bilirubin, platelet count, and age as significant contributors to ARDS prediction. Interpretation: The deep learning-based framework using the UNETR model demonstrated high accuracy and robustness in lung lesion segmentation and early ARDS prediction, and had good generalization ability and clinical applicability. Funding: This study was supported by grants from the Shanghai Renji Hospital Clinical Research Innovation and Cultivation Fund (RJPY-DZX-008) and Shanghai Science and Technology Development Funds (22YF1423300).
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Nanosizing confers unique functions in materials such as graphene and quantum dots. Here, we present two nanoscale-covalent organic frameworks (nano-COFs) that exhibit exceptionally high activity for photocatalytic hydrogen production that results from their size and morphology. Compared to bulk analogues, the downsizing of COFs crystals using surfactants provides greatly improved water dispersibility and light-harvesting properties. One of these nano-COFs shows a hydrogen evolution rate of 392.0 mmol g-1 h-1 (33.3 µmol h-1), which is one of the highest mass-normalized rates reported for a COF or any other organic photocatalysts. A reverse concentration-dependent photocatalytic phenomenon is observed, whereby a higher photocatalytic activity is found at a lower catalyst concentration. These materials also show a molecule-like excitonic nature, as studied by photoluminescence and transient absorption spectroscopy, which is again a function of their nanoscale dimensions. This charts a new path to highly efficient organic photocatalysts for solar fuel production.
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Staphylococcus xylosus has emerged as a bovine mastitis pathogen with increasing drug resistance, resulting in substantial economic impacts. This study utilized iTRAQ analysis to investigate the mechanisms driving resistance evolution in S. xylosus under ceftiofur sodium stress. Findings revealed notable variations in the expression of 143 proteins, particularly glycolysis-related proteins (TpiA, Eno, GlpD, Ldh) and peptidoglycan (PG) hydrolase Atl. Following the induction of ceftiofur sodium resistance in S. xylosus, the emergence of resistant strains displaying characteristics of small colony variants (SCVs) was observed. The transcript levels of TpiA, Eno, GlpD and Ldh were up-regulated, TCA cycle proteins (ICDH, MDH) and Atl were down-regulated, lactate content was increased, and NADH concentration was decreased in SCV compared to the wild strain. That indicates a potential role of carbon metabolism, specifically PG hydrolysis, glycolysis, and the TCA cycle, in the development of resistance to ceftiofur sodium in S. xylosus.
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Antibacterianos , Carbono , Cefalosporinas , Farmacorresistencia Bacteriana , Staphylococcus , Cefalosporinas/farmacología , Cefalosporinas/metabolismo , Antibacterianos/farmacología , Staphylococcus/efectos de los fármacos , Staphylococcus/genética , Staphylococcus/metabolismo , Carbono/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Animales , Bovinos , Glucólisis/efectos de los fármacos , Ciclo del Ácido Cítrico , Mastitis Bovina/microbiología , Infecciones Estafilocócicas/microbiología , Pruebas de Sensibilidad Microbiana , FemeninoRESUMEN
Chirality is an important aspect of nature, and numerous macroscopic methods have been developed to understand and control chirality. For the chiral tertiary amines, their flexible flipping process makes it possible to achieve high chiral controllability without bond formation and breaking. Here, we present a type of stable chiral single-molecule devices formed by tertiary amines, using graphene-molecule-graphene single-molecule junctions. These single-molecule devices allow real-time, in situ, and long-time measurements of the flipping process of an individual chiral nitrogen center with high temporal resolution. Temperature- and bias voltage-dependent experiments, along with theoretical investigations, revealed diverse chiral intermediates, indicating the regulation of the flipping dynamics by energy-related factors. Angle-dependent measurements further demonstrated efficient enrichment of chiral states using linearly polarized light by a symmetry-related factor. This approach offers a reliable means for understanding the chirality's origin, elucidating microscopic chirality regulation mechanisms, and aiding in the design of effective drugs.
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The intrinsic resistance of MRSA coupled with biofilm antibiotic tolerance challenges the antibiotic treatment of MRSA biofilm infections. Phytochemical-based nanoplatform is a promising emerging approach for treatment of biofilm infection. However, their therapeutic efficacy was restricted by the low drug loading capacity and lack of selectivity. Herein, we constructed a surface charge adaptive phytochemical-based nanoparticle with high isoliquiritigenin (ISL) loading content for effective treatment of MRSA biofilm. A dimeric ISL prodrug (ISL-G2) bearing a lipase responsive ester bond was synthesized, and then encapsulated into the amphiphilic quaternized oligochitosan. The obtained ISL-G2 loaded NPs possessed positively charged surface, which allowed cis-aconityl-d-tyrosine (CA-Tyr) binding via electrostatic interaction to obtain ISL-G2@TMDCOS-Tyr NPs. The NPs maintained their negatively charged surface, thus prolonging the blood circulation time. In response to low pH in the biofilms, the fast removal of CA-Tyr led to a shift in their surface charge from negative to positive, which enhanced the accumulation and penetration of NPs in the biofilms. Sequentially, the pH-triggered release of d-tyrosine dispersed the biofilm and lipase-triggered released of ISL effectively kill biofilm MRSA. An in vivo study was performed on a MRSA biofilm infected wound model. This phytochemical-based system led to â¼2 log CFU (>99 %) reduction of biofilm MRSA as compared to untreated wound (P < 0.001) with negligible biotoxicity in mice. This phytochemical dimer nanoplatform shows great potential for long-term treatment of resistant bacterial infections.
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Organic radicals exhibit great potential in photothermal applications, however, their innate high reactivity with oxygen renders the preparation of stable organic radicals highly challenging. In this work, a series of co-doped radical polymers ares prepared by doping dihydrophenazine derivatives (DPPs) into the epoxy resin matrix. DPPs can form radical species through the electron transfer process, which are further stabilized by the complex 3D network structure of epoxy resin. Experimental results show that the photothermal conversion efficiency is as high as 79.9%, and the temperature can quickly rise to ≈130 °C within 60 s. Due to the excellent visible light transmittance and mechanical properties of co-doped systems, this study further demonstrates their practical applications in energy-saving solar windows and thermoelectric power generation.
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Type I photodynamic therapy is considered to be a more promising cancer treatment than type II photodynamic therapy due to its non-oxygen-dependent characteristics. In this work, three D-A structure N,N'-dihydrophenazine (DHP)-based photosensitizers DP-CNPY, SMP-CNPY and DMP-CNPY were designed and synthesized by introducing different numbers of methyl groups in the backbone neighbor of DHP as the donor and combined with the typical strong electron acceptor 2-(pyridin-4-yl)acetonitrile. Among the three photosensitizers, SMP-CNPY with one methyl modification showed the best type I ROS (O2-Ë, ËOH) generation capacity and AIE performance. By encapsulation, SMP-CNPY was fabricated into nanoparticles, and SMP-CNPY NPs exhibited lipid droplet targeting ability with near-infrared (NIR) emission. Cell experiments have proved that SMP-CNPY NPs can effectively kill different kinds of cancer cells under normal oxygen conditions. Even under hypoxic and extreme hypoxic conditions, SMP-CNPY NPs can still produce ROS and kill cancer cells. This work holds significant potential in the field of type I AIE-active photosensitizers and provides a new strategy for overcoming the hypoxic dilemma in the malignant tumor microenvironment.
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Gotas Lipídicas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/síntesis química , Humanos , Gotas Lipídicas/química , Gotas Lipídicas/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Especies Reactivas de Oxígeno/metabolismo , Nanopartículas/química , Tamaño de la Partícula , Imagen Óptica , Supervivencia Celular/efectos de los fármacos , Estructura Molecular , Ensayos de Selección de Medicamentos Antitumorales , Línea Celular TumoralRESUMEN
With the proposal of the 2030 Agenda for Sustainable Development, the Chinese medicine extraction technology has been innovatively improved to prioritize low energy consumption, sustainability, and minimized organic solvent utilization. Forsythia suspensa (FS) possesses favorable pharmacological properties and is extensively utilized in traditional Chinese medicine. However, due to the limitations of the composition and extraction methods, its potential has not been fully developed. Thus, a combination of ultrasound-assisted extraction (UAE), enzyme-assisted extraction (EAE), and ß-cyclodextrin extraction (ß-CDE) was employed to isolate and purify rutin, phillyrin, and forsythoside A from FS. The results demonstrated that the efficiency of extracting enzymatic and ultrasound assisted ß-cyclodextrin extraction (EUA-ß-CDE) was highly influenced by the temperature and duration of hydrolysis, as well as the duration of the extraction process. According to the results of the single-factor experiment, Box-Behnken design (BBD) in Response surface method (RSM) was used to optimize the experimental parameters to achieve the maximum comprehensive evaluation value (CEV) value. The EUA-ß-CDE compared with other extraction methods, has good extraction effect and low energy consumption by high performance liquid chromatography (HPLC), scanning electron microscopy (SEM), calculation of power consumption and CO2 emission The EUA-ß-CDE compared with other extraction methods, has good extraction effect and low energy consumption by HPLC, SEM, calculation of power consumption and CO2 emission. Then, the structural characteristics of EUA-ß-CDE of FS extract had significant interaction with ß-CD by Fourier infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). In addition, EUA-ß-CDE extract has good antioxidant and anti-inflammatory activities. The establishment of EUA-ß-CDE of FS provides a new idea for the development and application of other sustainable extraction methods of traditional Chinese medicine.
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Antiinflamatorios , Antioxidantes , Forsythia , Ondas Ultrasónicas , beta-Ciclodextrinas , Forsythia/química , beta-Ciclodextrinas/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Fraccionamiento Químico/métodos , Enzimas/metabolismo , Temperatura , Glucósidos/aislamiento & purificación , Glucósidos/química , Glucósidos/farmacología , Hidrólisis , Rutina/aislamiento & purificación , Rutina/química , Rutina/farmacologíaRESUMEN
[This corrects the article DOI: 10.3389/fnins.2023.1321246.].
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OBJECTIVES: To observe the effect of electroacupuncture (EA) at different intensities on nociceptive discharges of wide dynamic range (WDR) neurons in the spinal dorsal horns (DHs) of rats, so as to explore its regulatory characteristics on nociceptive signals at the spinal level. METHODS: A total of 25 male SD rats were used in the present study. A microelectrode array was used to record the discharge activity of WDR neurons in the lumbar spinal DHs of normal rats. After finding the WDR neuron, electrical stimulation (pulse width of 2 ms) was administered to the plantar receptive field (RF) for determining its response component of discharges according to the latency of action potential generation (Aß ï¼»0 to 20 msï¼½, Aδ ï¼»20 to 90 msï¼½, C ï¼»90 to 500 msï¼½ and post-discharge ï¼»500 to 800 msï¼½). High-intensity electrical stimulation was continuously applied to the RF at the paw's plantar surface to induce DHs neuronal windup response. Subsequently, EA stimulation at different intensities (1 mA and 2 mA) was applied to the left "Zusanli"(ST36) at a frequency of 2 Hz/15 Hz for 10 min. The induction of WDR neuronal windup was then repeated under the same conditions. The quantity of nociceptive discharge components and the windup response of WDR neurons before and after EA stimulations at different intensities were compared. RESULTS: Compared to pre-EA, both EA1 mA and EA2 mA significantly reduced the number of Aδ and C component discharges of WDR neurons during stimulation, as well as post-discharge (P<0.01, P<0.001). The inhibitory rate of C component by EA2 mA was significantly higher than that by EA1 mA (P<0.05). Meanwhile, both EA1 mA and EA2 mA attenuated the windup response of WDR neurons (P<0.05, P<0.01), and the effect of EA2 mA was stronger than that of EA1 mA (P<0.05). Further analysis showed that when EA1 mA and EA2 mA respectively applied to both non-receptive field (non-RF) and RF, a significant reduction in the number of Aδ component, C component and post-discharge was observed (P<0.05, P<0.01). EA2 mA at the non-RF and RF demonstrated a significant inhibitory effect on the windup response of WDR neurons (P<0.01, P<0.05), but EA1 mA only at the non-RF showed a significant inhibitory effect on the windup response (P<0.01). CONCLUSIONS: EA can suppress nociceptive discharges of spinal DHs WDR neurons in rats. The inhibitory impact of EA is strongly correlated with the location and intensity of EA stimulation, and EA2 mA has a stronger inhibitory effect than EA1 mA.
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Puntos de Acupuntura , Electroacupuntura , Ratas Sprague-Dawley , Animales , Masculino , Ratas , Humanos , Nocicepción , Asta Dorsal de la Médula Espinal/fisiopatología , Células del Asta Posterior/fisiología , Potenciales de AcciónRESUMEN
BACKGROUND: The Corona Virus Disease 2019 (COVID-19) pandemic has struck globally. Whether the related proteins of retinoic acid (RA) signaling pathway are causally associated with the risk of COVID-19 remains unestablished. We conducted a two-sample Mendelian randomization (MR) study to assess the associations of retinol, retinol binding protein 4 (RBP4), retinol dehydrogenase 16 (RDH16) and cellular retinoic acid binding protein 1 (CRABP1) with COVID-19 in European population. METHODS: The outcome utilized the summary statistics of COVID-19 from the COVID-19 Host Genetics Initiative. The exposure data were obtained from public genome wide association study (GWAS) database. We extracted SNPs from exposure data and outcome data. The inverse variance weighted (IVW), MR-Egger and Wald ratio methods were employed to assess the causal relationship between exposure and outcome. Sensitivity analyses were performed to ensure the validity of the results. RESULTS: The MR estimates showed that retinol was associated with lower COVID-19 susceptibility using IVW (OR: 0.69, 95% CI: 0.53-0.90, P: 0.0065), whereas the associations between retinol and COVID-19 hospitalization or severity were not significant. RBP4 was associated with lower COVID-19 susceptibility using the Wald ratio (OR: 0.83, 95% CI: 0.72-0.95, P: 0.0072). IVW analysis showed RDH16 was associated with increased COVID-19 hospitalization (OR: 1.10, 95% CI: 1.01-1.18, P: 0.0199). CRABP1 was association with lower COVID-19 susceptibility (OR: 0.95, 95% CI: 0.91-0.99, P: 0.0290) using the IVW. CONCLUSIONS: We found evidence of possible causal association of retinol, RBP4, RDH16 and CRABP1 with the susceptibility, hospitalization and severity of COVID-19. Our study defines that retinol is significantly associated with lower COVID-19 susceptibility, which provides a reference for the prevention of COVID-19 with vitamin A supplementation.
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COVID-19 , Estudio de Asociación del Genoma Completo , Proteínas Plasmáticas de Unión al Retinol , SARS-CoV-2 , Vitamina A , Humanos , COVID-19/genética , COVID-19/epidemiología , Predisposición Genética a la Enfermedad , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Receptores de Ácido Retinoico/genética , Proteínas Plasmáticas de Unión al Retinol/metabolismo , Proteínas Plasmáticas de Unión al Retinol/genética , SARS-CoV-2/genética , Vitamina A/sangre , Vitamina A/metabolismoRESUMEN
This corrects the article 10.3791/65975.
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A Gram-negative, facultatively anaerobic, short rod-shaped bacterium, designated as strain HZ0627T, was isolated from the appendiceal pus of a patient with appendicitis in Yongzhou, Hunan, China. This strain was subjected to comprehensive phenotypic, phylogenetic, and genomic analyses using polyphasic taxonomic methods. Phylogenetic analysis of the 16S rRNA gene sequence revealed that this strain belonged to the genus Proteus and the family Morganellaceae, whereas that based on the rpoB gene sequence and phylogenomic analysis demonstrated that this strain was distinctly separated from other type strains of Proteus species. Moreover, whole-genome-based analyses, including in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI), revealed that strain HZ0627T had much lower isDDH rates (24.5-55.6%) and ANI (82.04-93.90%) than those of the thresholds (i.e., 70% and 95%, respectively) for species delineation, when compared to the type strains of other Proteus species. The cellular fatty acid profile of strain HZ0627T was dominated by C16:0 (34.5%), cyclo C17:0 (25.8%), C14:0 (12.6%), C16:1 iso I/14:0 3-OH (7.7%), C18:1ω7c/18:1ω6c (6.5%), and C16:1ω7c/16:1ω6c (4.9%), which clearly differentiated it from the documented type strains of Proteus species. In addition, several specific physiological traits, including optimal growth temperature, tolerance to sodium chloride, and carbon source utilization, differed from those of other Proteus species. Therefore, we propose the name Proteus appendicitidis sp. nov. for strain HZ0627T (= CCTCC AB 2022380T = KCTC 92986T), which represents the type strain of this novel Proteus species.
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Apendicitis , Humanos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Proteus/genética , Ácidos Grasos/análisis , China , ADN , Supuración , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Hibridación de Ácido NucleicoRESUMEN
A technique is described for surgically exposing the dorsal root ganglion (DRG) of the lumbar-6 in a live, anesthetized laboratory mouse, along with the protocol for in vivo calcium imaging of the exposed DRG in response to various visceral and somatic stimuli. Pirt-GCaMP6s mice or C57BL6 mice intrathecally injected with AAV viruses packaged with GCaMP6s were utilized to capture Ca2+ transients. The amplitude of these transients indicates sensitivity to specific sensory modalities. Afferent fibers originate from internal organs, with primary neuronal cell bodies in spinal or vagal ganglia. Studies on visceral nociception and acupuncture analgesia can potentially be conducted on primary sensory neurons using advanced imaging technologies like in vivo calcium imaging, allowing for the recording of neuronal activity ensembles in the intact animal during stimulation or intervention. The responses of DRG neuron ensembles to somatic and visceral stimuli applied to their corresponding receptive fields were recorded. This technique illustrates how neuronal populations react to various types of somatic and visceral stimuli. It is possible to comprehensively compare neuronal ensemble responses to different stimuli, which is a particularly valuable approach in research on visceral pain and segmental mechanisms of somatic stimulation, such as acupuncture.
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Calcio , Ganglios Espinales , Animales , Ratones , Ratones Endogámicos C57BL , Neuronas , Diagnóstico por ImagenRESUMEN
Epilepsy is a prevalent neurological disorder among women globally, often requiring long-term treatment. Hormonal fluctuations in women with epilepsy (WWE) can have reciprocal effects on epilepsy and antiseizure medications (ASMs), posing significant challenges for WWE. Notably, WWE commonly experience endocrine alterations such as thyroid dysfunctions, low bone metabolism, and reproductive hormone irregularities. On the one hand, the presence of hormones in women with epilepsy affects their susceptibility to epilepsy as well as the metabolism of antiseizure medications in various ways. On the other hand, epilepsy itself and the use of antiseizure medications impact the production, secretion, and metabolism of hormones, resulting in low fertility, increased risk of pregnancy complications, negative offspring outcomes, and so on. In order to develop more precise treatment strategies in the future, it is necessary to comprehend the explicit relationships between hormones, epilepsy, and antiseizure medications, as well as to elucidate the currently known mechanisms underlying these interactions.
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BACKGROUND: Aspergillus niger ATCC 20611 is an industrially important fructooligosaccharides (FOS) producer since it produces the ß-fructofuranosidase with superior transglycosylation activity, which is responsible for the conversion of sucrose to FOS accompanied by the by-product (glucose) generation. This study aims to consume glucose to enhance the content of FOS by heterologously expressing glucose oxidase and peroxidase in engineered A. niger. RESULTS: Glucose oxidase was successfully expressed and co-localized with ß-fructofuranosidase in mycelia. These mycelia were applied to synthesis of FOS, which possessed an increased purity of 60.63% from 52.07%. Furthermore, peroxidase was expressed in A. niger and reached 7.70 U/g, which could remove the potential inhibitor of glucose oxidase to facilitate the FOS synthesis. Finally, the glucose oxidase-expressing strain and the peroxidase-expressing strain were jointly used to synthesize FOS, which content achieved 71.00%. CONCLUSIONS: This strategy allows for obtaining high-content FOS by the multiple enzymes expressed in the industrial fungus, avoiding additional purification processes used in the production of oligosaccharides. This study not only facilitated the high-purity FOS synthesis, but also demonstrated the potential of A. niger ATCC 20611 as an enzyme-producing cell factory.
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Aspergillus niger , Aspergillus , beta-Fructofuranosidasa , Aspergillus niger/genética , Glucosa Oxidasa/genética , Oligosacáridos , Peroxidasas , GlucosaRESUMEN
Macrocyclic arenes have gained considerable attention for their structural diversity and widespread applications. In this research, a new kind of macrocyclic arenes, namely prism[2]dihydrophenazines (anti-P2P20, syn-P2P20, and P2P22), composed of two dihydrophenazine derivatives subunits bridged by methylene groups, were conveniently synthesized by AlCl3-catalyzed one-pot condensation in 1,2-dichloroethane. Both anti-P2P20 and its isomer syn-P2P20 exhibited flexible and convertible conformation with narrow cavity, while P2P22 possessed rigid and rhombic-like skeleton due to the more steric hindrance on subunits. In addition, the selection of electron-deficient guest was found to influence the outside binding behavior of syn-P2P20. Fantastic regular supramolecular tessellation was fabricated by tiling of syn-P2P20 with tetrafluoro-1,4-benzoquinone (TFB) through the exo-wall interactions. Using 1,5-difluoro-2,4-dinitrobenzene (DFN) as a linker, only the regular 2D network superstructure with periodic units in a plane was obtained through cocrystallization. This work not only reports the construction of supramolecular tessellations by using prism[2]dihydrophenazines as building blocks, but also provides a new perspective for the design of macrocyclic arenes and fabrication of 2D supramolecular materials.
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Sluggish sulfur redox kinetics and incessant shuttling of lithium polysulfides (LiPSs) greatly influence the electrochemical properties of lithium-sulfur (Li-S) batteries and their practical applications. For this reason, ammonium thiosulfate (AMTS) with effective redox regulation capability has been proposed as a functional electrolyte additive to promote the bidirectional conversion of sulfur species and inhibit the shuttle effect of soluble LiPSs. During discharging, the S2O32- in AMTS can trigger the rapid reduction of LiPSs from long chains to short chains by a spontaneous chemical reaction with sulfur species, thereby decreasing the accumulation of LiPSs in the electrolyte. During charging, the NH4+ in the AMTS enhances the dissociation/dissolution of Li2S2/Li2S by hydrogen-binding interactions, which alleviates the electrode surface passivation and facilitates the reversible oxidation of short-chain sulfides back to long chains. The enhanced bidirectional redox kinetics brought about by AMTS endows Li-S cells with high reversible capacity, excellent cycle stability, and rate capability even under lean electrolyte conditions. This work not only illustrates an effective redox regulation strategy by an electrolyte additive but also investigates its catalytic reaction mechanism and Li corrosion behavior. The crucial criteria for screening additives that enable bidirectional redox mediation analogous to AMTS are summarized, and its application perspectives/challenges are further discussed.