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1.
Carbohydr Polym ; 339: 122262, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-38823926

ABSTRACT

Chitosan has been widely used in biomedical fields due to its good antibacterial properties, excellent biocompatibility, and biodegradability. In this study, a pH-responsive and self-healing hydrogel was synthesized from 3-carboxyphenylboronic acid grafted with chitosan (CS-BA) and polyvinyl alcohol (PVA). The dynamic boronic ester bonds and intermolecular hydrogen bonds are responsible for the hydrogel formation. By changing the mass ratio of CS-BA and PVA, the tensile stress and compressive stress of hydrogel can controlled in the range of 0.61 kPa - 0.74 kPa and 295.28 kPa - 1108.1 kPa, respectively. After doping with tannic acid (TA)/iron nanocomplex (TAFe), the hydrogel successful killed tumor cells through the near infrared laser-induced photothermal conversion and the TAFe-triggered reactive oxygen species generation. Moreover, the photothermal conversion of the hydrogel and the antibacterial effect of CS and TA give the hydrogel a good antibacterial effect. The CS-BA/PVA/TAFe hydrogel exhibit good in vivo and in vitro anti-tumor recurrence and antibacterial ability, and therefore has the potential to be used as a powerful tool for the prevention of local tumor recurrence and bacterial infection after surgery.


Subject(s)
Anti-Bacterial Agents , Chitosan , Hydrogels , Neoplasm Recurrence, Local , Polyvinyl Alcohol , Tannins , Chitosan/chemistry , Chitosan/pharmacology , Hydrogels/chemistry , Hydrogels/pharmacology , Hydrogen-Ion Concentration , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Polyvinyl Alcohol/chemistry , Mice , Neoplasm Recurrence, Local/prevention & control , Tannins/chemistry , Tannins/pharmacology , Humans , Staphylococcus aureus/drug effects , Boronic Acids/chemistry , Escherichia coli/drug effects , Cell Line, Tumor , Reactive Oxygen Species/metabolism , Iron/chemistry , Surgical Wound Infection/prevention & control
2.
Burns Trauma ; 12: tkae004, 2024.
Article in English | MEDLINE | ID: mdl-38817684

ABSTRACT

Background: Extracellular cold-inducible RNA-binding protein (eCIRP) plays a vital role in the inflammatory response during cerebral ischaemia. However, the potential role and regulatory mechanism of eCIRP in traumatic brain injury (TBI) remain unclear. Here, we explored the effect of eCIRP on the development of TBI using a neural-specific CIRP knockout (KO) mouse model to determine the contribution of eCIRP to TBI-induced neuronal injury and to discover novel therapeutic targets for TBI. Methods: TBI animal models were generated in mice using the fluid percussion injury method. Microglia or neuron lines were subjected to different drug interventions. Histological and functional changes were observed by immunofluorescence and neurobehavioural testing. Apoptosis was examined by a TdT-mediated dUTP nick end labelling assay in vivo or by an annexin-V assay in vitro. Ultrastructural alterations in the cells were examined via electron microscopy. Tissue acetylation alterations were identified by non-labelled quantitative acetylation via proteomics. Protein or mRNA expression in cells and tissues was determined by western blot analysis or real-time quantitative polymerase chain reaction. The levels of inflammatory cytokines and mediators in the serum and supernatants were measured via enzyme-linked immunoassay. Results: There were closely positive correlations between eCIRP and inflammatory mediators, and between eCIRP and TBI markers in human and mouse serum. Neural-specific eCIRP KO decreased hemispheric volume loss and neuronal apoptosis and alleviated glial cell activation and neurological function damage after TBI. In contrast, eCIRP treatment resulted in endoplasmic reticulum disruption and ER stress (ERS)-related death of neurons and enhanced inflammatory mediators by glial cells. Mechanistically, we noted that eCIRP-induced neural apoptosis was associated with the activation of the protein kinase RNA-like ER kinase-activating transcription factor 4 (ATF4)-C/EBP homologous protein signalling pathway, and that eCIRP-induced microglial inflammation was associated with histone H3 acetylation and the α7 nicotinic acetylcholine receptor. Conclusions: These results suggest that TBI obviously enhances the secretion of eCIRP, thereby resulting in neural damage and inflammation in TBI. eCIRP may be a biomarker of TBI that can mediate the apoptosis of neuronal cells through the ERS apoptotic pathway and regulate the inflammatory response of microglia via histone modification.

3.
ACS Chem Neurosci ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38780450

ABSTRACT

Oxidative stress and neuroinflammation in the aging brain are correlated with the development of neurodegenerative diseases, such as Alzheimer's disease (AD). The blood-brain barrier (BBB) poses a significant challenge to the effective delivery of therapeutics for AD. Prior research has demonstrated that menthol (Men) can augment the permeability of the BBB. Consequently, in the current study, we modified Men on the surface of liposomes to construct menthol-modified quercetin liposomes (Men-Qu-Lips), designed to cross the BBB and enhance quercetin (Qu) concentration in the brain for improved therapeutic efficacy. The experimental findings indicate that Men-Qu-Lips exhibited good encapsulation efficiency and stability, successfully crossed the BBB, improved oxidative stress and neuroinflammation in the brains of aged mice, protected neurons, and enhanced their learning and memory abilities.

5.
J Plant Physiol ; 299: 154272, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38772322

ABSTRACT

Soil salinization-alkalization severely affects plant growth and crop yield worldwide, especially in the Songnen Plain of Northeast China. Saline-alkaline stress increases the pH around the plant roots, thereby limiting the absorption and transportation of nutrients and ions, such as iron (Fe). Fe is an essential micronutrient that plays important roles in many metabolic processes during plant growth and development, and it is acquired by the root cells via iron-regulated transporter1 (IRT1). However, the function of Oryza sativa IRT1 (OsIRT1) under soda saline-alkaline stress remains unknown. Therefore, in this study, we generated OsIRT1 mutant lines and OsIRT1-overexpressing lines in the background of the O. sativa Songjing2 cultivar to investigate the roles of OsIRT1 under soda saline-alkaline stress. The OsIRT1-overexpressing lines exhibited higher tolerance to saline-alkaline stress compared to the mutant lines during germination and seedling stages. Moreover, the expression of some saline-alkaline stress-related genes and Fe uptake and transport-related genes were altered. Furthermore, Fe and Zn contents were upregulated in the OsIRT1-overexpressing lines under saline-alkaline stress. Further analysis revealed that Fe and Zn supplementation increased the tolerance of O. sativa seedlings to saline-alkaline stress. Altogether, our results indicate that OsIRT1 plays a significant role in O. sativa by repairing the saline-alkaline stress-induced damage. Our findings provide novel insights into the role of OsIRT1 in O. sativa under soda saline-alkaline stress and suggest that OsIRT1 can serve as a potential target gene for the development of saline-alkaline stress-tolerant O. sativa plants.

6.
Molecules ; 29(9)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38731533

ABSTRACT

In this work, in order to investigate the short-range interactions between molecules, the spin-magnetic unit nitronyl nitroxide (NN) was introduced to synthesize self-assembly single radical molecules with hydrogen bond donors and acceptors. The structures and magnetic properties were extensively investigated and characterized by UV-Vis absorption spectroscopy, electron paramagnetic resonance (EPR), and superconducting quantum interference devices (SQUIDs). Interestingly, it was observed that the single molecules can form two different dimers (ring-closed dimer and "L"-type dimer) in different solvents, due to hydrogen bonding, when using EPR to track the molecular spin interactions. Both dimers exhibit ferromagnetic properties (for ring-closed dimer, J/kB = 0.18 K and ΔES-T = 0.0071 kcal/mol; for "L"-type dimer, the values were J/kB = 9.26 K and ΔES-T = 0.037 kcal/mol). In addition, the morphologies of the fibers formed by the two dimers were characterized by transmission electron microscopy (TEM) and atomic force microscopy (AFM).

7.
Cell Death Discov ; 10(1): 226, 2024 May 11.
Article in English | MEDLINE | ID: mdl-38734665

ABSTRACT

The functional alterations of proteins and nucleic acids mainly rely on their modifications. ADP-ribosylation is a NAD+-dependent modification of proteins and, in some cases, of nucleic acids. This modification is broadly categorized as Mono(ADP-ribosyl)ation (MARylation) or poly(ADP-ribosyl)ation (PARylation). MARylation catalyzed by mono(ADP-ribosyl) transferases (MARTs) is more common in cells and the number of MARTs is much larger than poly(ADP-ribosyl) transferases. Unlike PARylation is well-characterized, research on MARylation is at the starting stage. However, growing evidence demonstrate the cellular functions of MARylation, supporting its potential roles in human health and diseases. In this review, we outlined MARylation-associated proteins including MARTs, the ADP-ribosyl hydrolyses and ADP-ribose binding domains. We summarized up-to-date findings about MARylation onto newly identified substrates including protein, DNA and RNA, and focused on the functions of these reactions in pathophysiological conditions as well as speculated the potential mechanisms. Furthermore, new strategies of MARylation detection and the current state of MARTs inhibitors were discussed. We also provided an outlook for future study, aiming to revealing the unknown biological properties of MARylation and its relevant mechanisms, and establish a novel therapeutic perspective in human diseases.

8.
ACS Omega ; 9(18): 20223-20230, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38737042

ABSTRACT

In view of the problems in which the solid content of drilling fluid increases in the middle and late stages of horizontal well drilling, the lubricity of mud cakes on the borehole wall decreases, and the friction of pipe string increases due to the gradual thickening of mud cakes, which leads to the sticking and the obvious decrease of cementing strength at the second interface, a mud cake improver Mul-GX with lubrication and interface enhancement effect was studied in this paper. Based on the hydration and filling mechanism, the lubricity of the mud cake was improved, its thickness was reduced, and its strength was improved through synergistic effects of solvated water film lubrication and buffering, hardening and crystallization of gelled substances, and filling and dispersion of elastic particles. The mud cake improver Mul-GX is composed of the metasilicate GX-ZQ, polymer copolymer GX-JB, and polymer GX-TX, and the mass ratio of each component was GX-ZQ: GX-JB: GX-TX = 15:1:0.5. The effect of Mul-GX was evaluated through the performance determination of the mud cake and interface cementing simulation experiments. In addition, the microscopic characterization by SEM and XRD were carried out to analyze the mechanism of Mul-GX. The experimental results showed that when Mul-GX was added to the water-based drilling fluid with the 1.0%-1.5% adding quantity, the mud cake lubricity improved by more than 60%, its thickness reduced by 53.9% on average, and its strength increased by 54.3% on average. At the same adding quantity, the interfacial bonding strength was 4.4 times more than the data before adding Mul-GX. All of the results showed that Mul-GX has obvious mud cake lubrication effect and interface enhancement effect.

9.
J Hepatocell Carcinoma ; 11: 801-812, 2024.
Article in English | MEDLINE | ID: mdl-38737385

ABSTRACT

Purpose: The patterns and risk factors of postsurgical recurrence of patient with hepatocellular carcinoma (HCC) with microvascular invasion (MVI) are not clarified. This study aimed to decipher and compare the postoperative recurrent patterns and the risk factors contributing to recurrence between MVI positive (MVI(+)) and MVI negative (MVI(-)) HCC after hepatectomy. Patients and methods: Patients with HCC who underwent hepatectomy in three Chinese academic hospitals between January 1, 2009, and December 31, 2018, were enrolled. Recurrent patterns included early (≤2 years) or late (>2 years) recurrence, recurrent sites and number, and risk factors of recurrence were compared between the MVI(+)and MVI(-) groups by propensity score-matching (PSM). Results: Of 1756 patients included, 581 (33.1%) were MVI(+), and 875 (49.8%) patients developed early recurrence. Compared with the MVI(-) group, the MVI(+) group had a higher 2-year recurrence rate in the PSM cohort (hazard ratio [HR], 1.82; 95% confidence interval [CI], 1.59-2.10; P < 0.001), and more patients with multiple tumor recurrence. Patients with early recurrence in the MVI(+) group had a worse overall survival (OS) than those in the MVI(-) group (HR, 1.24; 95% CI, 1.02-1.50; P = 0.034). Resection margin (RM) ≤1.0 cm is a surgical predictor of early recurrence for the MVI(+) group (HR, 0.68; 95% CI, 0.54-0.87; P = 0.002), but not for the MVI(-) group. Conclusion: Compared to MVI(-) HCC, MVI(+) HCC tends to be early, multiple recurrence and lung and lymph node metastasis after resection. RM ≤1.0 cm is a surgical risk factor of early recurrence for patient with MVI.

10.
Arch Sex Behav ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769279

ABSTRACT

The Revised Sociosexual Orientation Inventory (SOI-R) is a measurement tool for assessing an individual's willingness to engage in uncommitted sexual relations. Despite its widespread use in various contexts, no studies have validated the use of this instrument in China. Therefore, the current study aimed to assess the reliability and validity of an existing Chinese translation of the SOI-R. A total of 2,209 participants were recruited and randomly divided into two groups: exploratory factor analysis was conducted on one group and confirmatory factor analysis on the other, with 161 participants from the total sample recruited to assess the test-retest reliability. Criterion validity was measured by testing the correlations between sociosexuality and sexual desire, mate value, sexual attitudes, and personality traits. The results confirmed a three-factor structure (sociosexual behaviors, attitudes, and desire) for the SOI-R. Furthermore, the findings demonstrated good reliability (internal consistency and test-retest stability) and validity (criterion validity, convergent validity, and discriminant validity) of the SOI-R, supporting its suitability as an assessment tool for sociosexual orientation in China.

11.
Animal Model Exp Med ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38769667

ABSTRACT

BACKGROUND: Thromboelastography (TEG) is a widely utilized clinical testing method for real-time monitoring of platelet function and the thrombosis process. Lipid metabolism disorders are crucial risk factors for thrombosis. The lipid metabolism characteristics of hamsters resemble those of humans more closely than mice and rats, and their relatively large blood volume makes them suitable for studying the mechanisms of thrombosis related to plasma lipid mechanisms. Whole blood samples from golden Syrian hamsters and healthy humans were obtained following standard clinical procedures. TEG was employed to evaluate coagulation factor function, fibrinogen (Fib) function, platelet function, and the fibrinolytic system. METHODS: The whole blood from hamster or healthy human was isolated following the clinical procedure, and TEG was employed to evaluate the coagulation factor function, Fib function, platelet function, and fibrinolytic system. Coagulation analysis used ACLTOP750 automatic coagulation analysis pipeline. Blood routine testing used XN-2000 automatic blood analyzer. RESULTS: TEG parameters revealed that hamsters exhibited stronger coagulation factor function than humans (reaction time [R], p = 0.0117), with stronger Fib function (alpha angle, p < 0.0001; K-time [K], p < 0.0001). Platelet function did not differ significantly (maximum amplitude [MA], p = 0.077). Hamsters displayed higher coagulation status than humans (coagulation index [CI], p = 0.0023), and the rate of blood clot dissolution in hamsters differed from that in humans (percentage lysis 30 min after MA, p = 0.02). Coagulation analysis parameters indicated that prothrombin time (PT) and activated partial thromboplastin time (APTT) were faster in hamsters than in humans (PT, p = 0.0014; APTT, p = 0.03), whereas the Fib content was significantly lower in hamsters than in humans (p < 0.0001). No significant difference was observed in thrombin time (p = 0.1949). CONCLUSIONS: In summary, TEG could be used to evaluate thrombosis and bleeding parameters in whole blood samples from hamsters. The platelet function of hamsters closely resembled that of humans, whereas their coagulation function was significantly stronger.

12.
ACS Nano ; 18(20): 13117-13129, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38727027

ABSTRACT

The complexity, heterogeneity, and drug resistance of diseases necessitate a shift in therapeutic paradigms from monotherapy to combination therapy, which could augment treatment efficiency. Effective treatment of advanced osteoarthritis (OA) requires addressing three key factors contributing to its deterioration: chronic joint inflammation, lubrication dysfunction, and cartilage-tissue degradation. Herein, we present a supramolecular nanomedicine of multifunctionality via molecular recognition and self-assembly. The employed macrocyclic carrier, zwitterion-modified cavitand (CV-2), not only accurately loads various drugs but also functions as a therapeutic agent with lubricating properties for the treatment of OA. Kartogenin (KGN), a drug for articular cartilage regeneration and protection, and flurbiprofen (FP), an anti-inflammatory agent, were coloaded onto CV-2 assembly, forming a supramolecular nanomedicine KGN&FP@CV-2. The three-in-one combination therapy of KGN&FP@CV-2 addresses the three pathological features for treating OA collectively, and thus provides long-term therapeutic benefits for OA through sustained drug release and intrinsic lubrication in vivo. The multifunctional integration of macrocyclic delivery and therapeutics provides a simple, flexible, and universal platform for the synergistic treatment of diseases involving multiple drugs.


Subject(s)
Flurbiprofen , Osteoarthritis , Osteoarthritis/drug therapy , Osteoarthritis/pathology , Animals , Flurbiprofen/chemistry , Flurbiprofen/administration & dosage , Flurbiprofen/pharmacology , Phthalic Acids/chemistry , Phthalic Acids/pharmacology , Drug Delivery Systems , Humans , Drug Carriers/chemistry , Lubrication , Drug Liberation , Mice , Male , Anilides
13.
Cell Death Discov ; 10(1): 237, 2024 May 18.
Article in English | MEDLINE | ID: mdl-38762523

ABSTRACT

Immunotherapy has now garnered significant attention as an essential component in cancer therapy during this new era. However, due to immune tolerance, immunosuppressive environment, tumor heterogeneity, immune escape, and other factors, the efficacy of tumor immunotherapy has been limited with its application to very small population size. Energy metabolism not only affects tumor progression but also plays a crucial role in immune escape. Tumor cells are more metabolically active and need more energy and nutrients to maintain their growth, which causes the surrounding immune cells to lack glucose, oxygen, and other nutrients, with the result of decreased immune cell activity and increased immunosuppressive cells. On the other hand, immune cells need to utilize multiple metabolic pathways, for instance, cellular respiration, and oxidative phosphorylation pathways to maintain their activity and normal function. Studies have shown that there is a significant difference in the energy expenditure of immune cells in the resting and activated states. Notably, competitive uptake of glucose is the main cause of impaired T cell function. Conversely, glutamine competition often affects the activation of most immune cells and the transformation of CD4+T cells into inflammatory subtypes. Excessive metabolite lactate often impairs the function of NK cells. Furthermore, the metabolite PGE2 also often inhibits the immune response by inhibiting Th1 differentiation, B cell function, and T cell activation. Additionally, the transformation of tumor-suppressive M1 macrophages into cancer-promoting M2 macrophages is influenced by energy metabolism. Therefore, energy metabolism is a vital factor and component involved in the reconstruction of the tumor immune microenvironment. Noteworthy and vital is that not only does the metabolic program of tumor cells affect the antigen presentation and recognition of immune cells, but also the metabolic program of immune cells affects their own functions, ultimately leading to changes in tumor immune function. Metabolic intervention can not only improve the response of immune cells to tumors, but also increase the immunogenicity of tumors, thereby expanding the population who benefit from immunotherapy. Consequently, identifying metabolic crosstalk molecules that link tumor energy metabolism and immune microenvironment would be a promising anti-tumor immune strategy. AMPK (AMP-activated protein kinase) is a ubiquitous serine/threonine kinase in eukaryotes, serving as the central regulator of metabolic pathways. The sequential activation of AMPK and its associated signaling cascades profoundly impacts the dynamic alterations in tumor cell bioenergetics. By modulating energy metabolism and inflammatory responses, AMPK exerts significant influence on tumor cell development, while also playing a pivotal role in tumor immunotherapy by regulating immune cell activity and function. Furthermore, AMPK-mediated inflammatory response facilitates the recruitment of immune cells to the tumor microenvironment (TIME), thereby impeding tumorigenesis, progression, and metastasis. AMPK, as the link between cell energy homeostasis, tumor bioenergetics, and anti-tumor immunity, will have a significant impact on the treatment and management of oncology patients. That being summarized, the main objective of this review is to pinpoint the efficacy of tumor immunotherapy by regulating the energy metabolism of the tumor immune microenvironment and to provide guidance for the development of new immunotherapy strategies.

14.
Biochem Biophys Res Commun ; 720: 150065, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38749188

ABSTRACT

Neovascular eye diseases, including proliferative diabetic retinopathy and retinopathy of prematurity, is a major cause of blindness. Laser ablation and intravitreal anti-VEGF injection have shown their limitations in treatment of retinal neovascularization. Identification of a new therapeutic strategies is in urgent need. Our study aims to assess the effects of Cryptotanshinone (CPT), a natural compound derived from Salvia miltiorrhiza Bunge, in retina neovascularization and explore its potential mechanism. Our study demonstrated that CPT did not cause retina tissue toxicity at the tested concentrations. Intravitreal injections of CPT reduced pathological angiogenesis and promoted physical angiogenesis in oxygen-induced retinopathy (OIR) model. CPT improve visual function in OIR mice and reduced cell apoptosis. Moreover, we also revealed that CPT diminishes the expression of inflammatory cytokines in the OIR retina. In vitro, the administration of CPT effectively inhibited endothelial cells proliferation, migration, sprouting, and tube formation induced by the stimulation of human retinal vascular endothelial cells (HRVECs) with VEGF165. Mechanistically, CPT blocking the phosphorylation of VEGFR2 and downstream targeting pathway. After all, the findings demonstrated that CPT exhibits potent anti-angiogenic and anti-inflammatory effects in OIR mice, and it has therapeutic potential for the treatment of neovascular retinal diseases.

15.
Sci Rep ; 14(1): 11094, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38750028

ABSTRACT

Traditional 2D imaging technologies are limited by the need for a large field of view and their sensitivity to small target motion. Inspired by the characteristics of insect compound eye structure, we propose an infrared bionic compound eye camera based on a small lens array. The camera is composed of 61 small lens arrays mounted on a curved spherical shell and a relay optical system. The imaging device is a high-performance cooled mid-wave infrared detector. This is an innovative design for an infrared biomimetic compound eye camera system that provides a wide field of view and all-day detection capability. Aimed to meet the specified requirements. The optical system achieves a 100% cold-membrane match between the infrared optical system and the cooled detector, and the relay optical system optimizes the large-field aberration by introducing a higher-order aspheric surface and modifying the geometric surface of the lenses. Our entire system enables an observation field angle of 108 ∘ × 108 ∘ . The experiments showed that the image quality of the system is high, each ommatidium was effective within the imaging range of the compound eye camera, resulting in an improved signal-to-noise ratio in various scenes.

16.
ACS Appl Mater Interfaces ; 16(19): 25589-25599, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38696218

ABSTRACT

The newly emerging liquid metal flexible electronics are gaining increasing applications over the world due to their outstanding adaptability and printability. Here, we proposed a generalized purpose thermo-activated hybrid transfer printing method for the rapid fabrication of multifunctional soft electronics, which can significantly reduce the difficulty facing existing technologies. This printing involves two delivery and deposition processes of liquid metals and the allied inks (toners) based on their adhesion selection mechanisms. Through developing office supplies, the laser printer could directly print toner masks on soft substrates, such as polydimethylsiloxane film. The heating plate was applied to remove the toner sacrificial mask after rolling liquid metal inks, resulting in retaining the liquid metal circuits on the target substrate. For illustration, diverse materials and inks are adapted to the strategy of constructing flexible electronics. Particularly, colorful circuits, flexible heaters, transparent circuitry, and soft programmable light-emitting diode array displays with multilayer circuits have been fabricated and tested. This general and easily accessible method allows for the rapid acquisition of user-designed soft electronics and is expected to promote the widespread use of flexible electronics in e-skin, sensing, displays, etc.

17.
Nat Commun ; 15(1): 4042, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38740739

ABSTRACT

Antennas that can operate across multiple communication standards have remained a challenge. To address these limitations, we propose a Field-Programmable Radio Frequency Surface (FPRFS), which is based on manipulating current flow on its surface to achieve desirable RF characteristics. In this work, we demonstrate that substantial enhancements in radiation efficiency can be achieved while preserving the high reconfigurability of antenna structures implemented on the FPRFS. This is accomplished by utilizing an asymmetric excitation, directing the excitation to the low-loss contiguous surface, and dynamically manipulating the imaged return current on a segmented ground plane by switches. This important insight allows for adaptable antenna performance that weakly depends on the number of RF switches or their loss. We experimentally validate that FPRFS antennas can achieve efficiencies comparable to traditionally implemented antenna counterparts. This permits the FPRFS to be effectively utilized as a productive antenna and impedance-matching network with real-time reconfigurability.

18.
Front Microbiol ; 15: 1323842, 2024.
Article in English | MEDLINE | ID: mdl-38751718

ABSTRACT

Objective: Gastric and intestinal diseases possess distinct characteristics although they are interconnected. The primary objective of this study was to investigate the pathogenesis of gastrointestinal diseases through different analyses of clinical characteristics, serum immunology, and gut microbiota in patients with gastrointestinal diseases. Methods: We collected serum samples from 89 patients with gastrointestinal diseases and 9 healthy controls for immunological assessment, stool samples for DNA extraction, library construction, sequencing, as well as clinical data for subsequent analysis. Results: Regarding clinical characteristics, there were significant differences between the disease group and the healthy control (HC) group, particularly in terms of age, cancer antigen 125 (CA125), cancer antigen 199 (CA199), alpha-fetoprotein (AFP), total bilirubin (TBIL) and indirect bilirubin (IBIL). The intestinal disease (ID) group exhibited the highest IL-6 level, which significantly differed from the stomach disease (SD) group (p < 0.05). In comparing the HC with the ID groups, significant differences in abundance were detected across 46 species. The HC group displayed a greater abundance of Clostridiales, Clostridia, Firmicutes, Bifidobacterium, Bifidobacteriaceae, Bifidobacteriales, Actinobacteria, Veillonellaceae, Longum, Copri, Megamonas and Callidus than other species. Similarly, when comparing the HC with the SD groups, significant differences in abundance were identified among 49 species, with only one species that the Lachnospiraceae in the HC group exhibited a higher abundance than others. Furthermore, certain clinical characteristics, such as CA125, CA199, glucose (Glu), creatine kinase-MB (CKMB) and interleukin-22 (IL-22), displayed positive correlations with enriched gut species in the ID and SD groups, while exhibiting a negative correlation with the HC group. Conclusion: The disturbance in human gut microbiota is intimately associated with the development and progression of gastrointestinal diseases. Moreover, the gut microbiota in the HC group was found more diverse than that in the ID and SD groups, and there were significant differences in microbial species among the three groups at different classification levels. Notably, a correlation was identified between specific clinical characteristics (e.g., CA125, CA199, Glu, CKMB and IL-22) and gut microbiota among patients with gastrointestinal diseases.

19.
Chemistry ; : e202400651, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38705845

ABSTRACT

PEMWE is considered a promising technology for coupling with renewable energy sources to achieve clean hydrogen production. However, constrained by the sluggish kinetics of the anodic OER and the acidic abominable environment render the grand challenges in developing the active and stable OER electrocatalyst, leading to low efficiency of PEMWE. Herein, we develop the rutile-type IrO2 nanoparticles with abundant grain boundaries and the continuous nanostructure through the joule heating and sacrificial template method. DFT calculations verified that grain boundaries can modulate the electronic structure of Ir sites and optimize the adsorption of oxygen intermediates, resulting in the accelerated kinetics. The 350-IrO2 affords a rapid OER process with 20 times higher mass activity (0.61 A mgIr-1) than the commercial IrO2 at 1.50 V vs. RHE. Benefiting from the reduced overpotential and the preservation of the stable rutile structure, 350-IrO2 exhibits the stability of 200 h test at 10 mA cm-2 with only trace decay of 11.8 mV. Moreover, the assembled PEMWE with anode 350-IrO2 catalyst outputs the current density up to 2 A cm-2 with only 1.84 V applied voltage, long-term operation for 100 h without obvious performance degradation at 1 A cm-2.

20.
Science ; 384(6698): 890-894, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38781391

ABSTRACT

Primordial neutral atomic gas, mostly composed of hydrogen, is the raw material for star formation in galaxies. However, there are few direct constraints on the amount of neutral atomic hydrogen (H i) in galaxies at early cosmic times. We analyzed James Webb Space Telescope (JWST) near-infrared spectroscopy of distant galaxies, at redshifts ≳8. From a sample of 12 galaxies, we identified three that show strong damped Lyman-α absorption due to H i in their local surroundings. The galaxies are located at spectroscopic redshifts of 8.8, 10.2, and 11.4, corresponding to 400 to 600 million years after the Big Bang. They have H i column densities ≳1022 cm-2, which is an order of magnitude higher than expected for a fully neutral intergalactic medium, and constitute a gas-rich population of young star-forming galaxies.

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