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1.
Nano Lett ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38747348

RESUMEN

Two-dimensional semiconductor materials with vertical dipoles are promising photocatalysts as vertical dipoles not only promote the electron-hole separation but also enhance the carrier redox ability. However, the influence of vertical dipoles on carrier recombination in such materials, especially the competing relationship between vertical dipoles and band gaps, is not yet clear. Herein, first-principles calculations and nonadiabatic molecular dynamics simulations were combined to clarify the influence of band gap and vertical dipole on the carrier lifetime in Janus MoSSe monolayer. By comparing with the results of MoS2 and MoSe2 as well as exploring the carrier lifetime of MoSSe under strain regulation, it has been demonstrated that the vertical dipole, rather than the band gap, is the dominant factor affecting the carrier lifetime. Strikingly, a linear relationship between the carrier lifetime and vertical dipole is revealed. These findings have important implications for the design of high-performance photocatalysts and optoelectronic devices.

2.
Chem Sci ; 15(18): 6916-6923, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38725518

RESUMEN

Two-dimensional (2D) nonmagnetic semiconductors with large Rashba-Dresselhaus (R-D) spin splitting at valence or conduction bands are attractive for magnetic-field-free spintronic applications. However, so far, the number of 2D R-D inorganic semiconductors has been quite limited, and the factors that determine R-D spin splitting as well as rational design of giant spin splitting, remain unclear. For this purpose, by exploiting 2D chiral metal-organic frameworks (CMOFs) as a platform, we theoretically develop a three-step screening method to obtain a series of candidate 2D R-D semiconductors with valence band spin splitting up to 97.2 meV and corresponding R-D coupling constants up to 1.37 eV Å. Interestingly, the valence band spin texture is reversible by flipping the chirality of CMOFs. Furthermore, five keys for obtaining giant R-D spin splitting in 2D CMOFs are successfully identified: (i) chirality, (ii) large spin-orbit coupling, (iii) narrow band gap, (iv) valence and conduction bands having the same symmetry at the Γ point, and (v) strong ligand field.

3.
Microbiol Spectr ; : e0035424, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38709085

RESUMEN

Paeniclostridium sordellii hemorrhagic toxin (TcsH) and Clostridioides difficile toxin A (TcdA) are two major members of the large clostridial toxin (LCT) family. These two toxins share ~87% similarity and are known to cause severe hemorrhagic pathology in animals. Yet, the pathogenesis of their hemorrhagic toxicity has been mysterious for decades. Here, we examined the liver injury after systemic exposure to different LCTs and found that only TcsH and TcdA induce overt hepatic hemorrhage. By investigating the chimeric and truncated toxins, we demonstrated that the enzymatic domain of TcsH alone is not sufficient to determine its potent hepatic hemorrhagic toxicity in mice. Likewise, the combined repetitive oligopeptide (CROP) domain of TcsH/TcdA alone also failed to explain their strong hemorrhagic activity in mice. Lastly, we showed that disrupting the first two short repeats of CROPs in TcsH and TcdA impaired hemorrhagic toxicity without causing overt changes in cytotoxicity and lethality. These findings lead to a deeper understanding of toxin-induced hemorrhage and the pathogenesis of LCTs and could be insightful in developing therapeutic avenues against clostridial infections. IMPORTANCE: Paeniclostridium sordellii and Clostridioides difficile infections often cause hemorrhage in the affected tissues and organs, which is mainly attributed to their hemorrhagic toxins, TcsH and TcdA. In this study, we demonstrate that TcsH and TcdA, but not other related toxins. including Clostridioides difficile toxin B and TcsL, induce severe hepatic hemorrhage in mice. We further determine that a small region in TcsH and TcdA is critical for the hemorrhagic toxicity but not cytotoxicity or lethality of these toxins. Based on these results, we propose that the hemorrhagic toxicity of TcsH and TcdA is due to an uncharacterized mechanism, such as the presence of an unknown receptor, and future studies to identify the interactive host factors are warranted.

4.
Int J Biol Macromol ; : 132335, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38768923

RESUMEN

Development of renewable and biodegradable plastics with good properties, such as the gas barrier, UV-shielding, solvent resistance, and antibacterial activity, remains a challenge. Herein, cellulose/ZnO based bioplastics were fabricated by dissolving cellulose carbamate in an aqueous solution of NaOH/Zn(OH)42-, followed by coagulation in aqueous Na2SO4 solution, and subsequent hot-pressing. The carbamate groups detached from cellulose, and ZnO which transformed from cosolvent to nanofiller was uniformly immobilized in the cellulose matrix during the dissolution/regeneration process. The appropriate addition of ZnO (below 10.67 wt%) not only improved the mechanical properties but also enhanced the water and oxygen barrier properties of the material. Additionally, our cellulose/ZnO based bioplastic demonstrated excellent UV-blocking capabilities, increased water contact angle, and enhanced antibacterial activity against S. aureus and E. coli, deriving from the incorporation of ZnO nanoparticles. Furthermore, the material exhibited resistance to organic solvents such as acetone, THF, and toluene. Indeed, the herein developed cellulose/ZnO based bioplastic presents a promising candidate to replace petrochemical plastics in various applications, such as plastic toys, anti-UV guardrails, window shades, and oil storage containers, offering a combination of favorable mechanical, gas barrier, UV-blocking, antibacterial, and solvent-resistant properties.

5.
Heliyon ; 10(9): e30445, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38737261

RESUMEN

Objective: To investigate the involvement of the homeobox gene B5 (HOXB5) in the progression and metastasis of osteosarcoma. Methods: The expression of HOXB5 in human osteosarcoma tissues and its correlation with clinical indicators were investigated using bioinformatics analysis and immunohistochemical labelling. Human osteosarcoma cells (HOS, MG63, U2OS, and Saos-2) and normal human osteoblasts (hFOB1.19) were cultivated. The expression of HOXB5 in these cells was detected using western blotting (WB) and RT‒PCR. Two cell lines exhibiting elevated HOXB5 expression were chosen and divided into three groups: the blank group (mock), control group (control) and transfection group (shHOXB5). The transfection group was infected with lentivirus expressing shRNAs targeting HOXB5. The transfection efficiency was detected by WB. Cell proliferation suppression was measured by CCK-8 and 5-ethynyl-2'-deoxyuridine (EdU) assays; the percentage of apoptotic cells was determined by flow cytometry; and cell migration and invasion were detected via the Transwell chamber test. WB was utilized to determine the protein expression of genes linked to metastasis (MMP2, MMP9), apoptosis (Bax, Bcl-2), and the JAK2/STAT3 pathway (JAK2, p-JAK2, STAT3, p-STAT3). Results: In osteosarcoma tissues, HOXB5 expression was elevated and strongly correlated with distant metastasis. Silencing HOXB5 reduced the proliferation, migration and invasion of osteosarcoma cells; prevented the progression and metastasis of tumours in tumour-bearing nude mice; and reduced the activation of key proteins in the JAK2/STAT3 signalling pathway. Conclusion: Through the JAK2/STAT3 signalling pathway, HOXB5 plays a crucial role in the malignant progression of osteosarcoma and is a promising target for osteosarcoma treatment.

6.
Front Immunol ; 15: 1374486, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38745651

RESUMEN

A universal recombinant adenovirus type-5 (Ad5) vaccine against COVID19 (Ad-US) was constructed, and immunogenicity and broad-spectrum of Ad5-US were evaluated with both intranasal and intramuscular immunization routes. The humoral immune response of Ad5-US in serum and bronchoalveolar lavage fluid were evaluated by the enzyme-linked immunosorbent assay (ELISA), recombinant vesicular stomatitis virus based pseudovirus neutralization assay, and angiotensin-converting enzyme-2 (ACE2) -binding inhibition assay. The cellular immune response and Th1/Th2 biased immune response of Ad5-US were evaluated by the IFN-γ ELISpot assay, intracellular cytokine staining, and Meso Scale Discovery (MSD) profiling of Th1/Th2 cytokines. Intramuscular priming followed by an intranasal booster with Ad5-US elicited the broad-spectrum and high levels of IgG, IgA, pseudovirus neutralizing antibody (PNAb), and Th1-skewing of the T-cell response. Overall, the adenovirus type-5 vectored universal SARS-CoV-2 vaccine Ad5-US was successfully constructed, and Ad5-US was highly immunogenic and broad spectrum. Intramuscular priming followed by an intranasal booster with Ad5-US induced the high and broad spectrum systemic immune responses and local mucosal immune responses.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Vectores Genéticos , SARS-CoV-2 , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , COVID-19/inmunología , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Ratones , Humanos , Femenino , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , Adenoviridae/genética , Adenoviridae/inmunología , Ratones Endogámicos BALB C , Administración Intranasal , Inyecciones Intramusculares , Inmunidad Humoral , Citocinas/metabolismo , Inmunidad Celular
7.
J Fluoresc ; 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639858

RESUMEN

Two fluorescent probes, Y1-2 were synthesized from 2-acetonaphthone, 4-acetylbiphenyl, and phenyl hydrazine by Vilsmeier-Haack reaction and Knoevenagel condensation. Their recognition efficacies for N2H4 were tested by UV-visible absorption spectroscopy and fluorescence emission spectroscopy. The recognition mechanism were studies by density-functional theory calculations, and the effect of pH on N2H4 recognition was also studied. The results showed that the probe Y1-2 has high selectivity and a low detection limit for N2H4, and the recognition of N2H4 can be accomplished at physiological pH. The probes have had obvious aggregation-induced luminescence effect, large Stokes shift, high sensitivity, and can be successfully applied to live cell imaging.

8.
J Genet Genomics ; 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38575110

RESUMEN

The highly conserved CLV-WUS negative feedback pathway plays a decisive role in regulating stem cell maintenance in shoot and floral meristems in higher plants, including Arabidopsis, rice, maize, and tomato. Here, we report the discovery that CLV-like genes directly regulate grain shape in rice. We find significant natural variations in the OsCLV2c, OsCLV2d, and OsCRN1 loci in a genome-wide association study of grain shape in rice. OsCLV2a, OsCLV2c, OsCLV2d, and OsCRN1 negatively regulate grain length-width ratio and show distinctive geographical distribution, indica-japonica differentiation, and artificial selection signatures. Notably, OsCLV2a and OsCRN1 interact biochemically and genetically, suggesting that the two components function in a complex to regulate grain shape of rice. Furthermore, the genetic contributions of the haplotypes combining OsCLV2a, OsCLV2c, and OsCRN1 are significantly higher than those of each single gene alone in controlling key yield traits. These findings identify two groups of receptor-like kinases that may function as distinct co-receptors to control grain size in rice, thereby revealing a previously unrecognized role of the CLV class genes in regulating seed development and proposing a framework to understand the molecular mechanisms of the CLV-WUS pathway in rice and other crops.

9.
Medicine (Baltimore) ; 103(14): e37683, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38579075

RESUMEN

Since the emergence of the Coronavirus Disease 2019 (COVID-19) outbreak, significant advancements has been made in research, from limited knowledge about the disease to the development of a vaccine. Although the severity of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) appears to be decreasing and the threat of COVID-19 is waning, there have been widespread concerns about persistent symptoms or sequelae experienced by some patients even after recovering from COVID-19. Traditional Chinese medicine (TCM) has shown favorable treatment outcomes during the onset of COVID-19, and extensive studies have been carried out to explore the efficacy of TCM interventions during the COVID-19 recovery period. The purpose of this review is to comprehensively analyze these studies and provide new insights for the prevention and treatment of the post-COVID-19 condition.


Asunto(s)
COVID-19 , Medicamentos Herbarios Chinos , Humanos , Medicina Tradicional China , SARS-CoV-2 , Medicamentos Herbarios Chinos/uso terapéutico , Tratamiento Farmacológico de COVID-19
10.
J Phys Chem Lett ; 15(15): 4218-4223, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38602298

RESUMEN

Two-dimensional (2D) ferroelectric metals (FEMs) possess intriguing characteristics, such as unconventional superconductivity and the nonlinear anomalous Hall effect. However, their occurrence is exceedingly rare due to mutual repulsion between ferroelectricity and metallicity. In addition, further incorporating other features like ferromagnetism into FEMs to enhance their functionalities poses a significantly greater challenge. Here, via first-principles calculations, we demonstrate a case of an FEM that features a coexistence of room-temperature ferromagnetism, ferroelectricity, and metallicity in a thermodynamically stable 2D Os2Se3. It presents a vertical electric polarization of 3.00 pC/m that exceeds those of most FEMs and a moderate polarization switching barrier of 0.22 eV per formula unit. Moreover, 2D Os2Se3 exhibits robust ferromagnetism (Curie temperature TC ≈ 527 K) and a sizable magnetic anisotropy energy (-30.87 meV per formula unit). Furthermore, highly magnetization-dependent electrical conductivity is revealed, indicative of strong magnetoelectric coupling. Berry curvature calculation suggests that the FEM might exhibit nontrivial band topology.

11.
Front Microbiol ; 15: 1384166, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686114

RESUMEN

Objectives: Although metagenomic next-generation sequencing (mNGS) is commonly used for diagnosing infectious diseases, clinicians face limited options due to the high costs that are not covered by basic medical insurance. The goal of this research is to challenge this bias through a thorough examination and evaluation of the clinical importance of mNGS in precisely identifying pathogenic microorganisms in cases of sepsis acquired in the community or in hospitals. Methods: A retrospective observational study took place at a tertiary teaching hospital in China from January to December 2021. Data on 308 sepsis patients were collected, and the performance of etiological examination was compared between mNGS and traditional culture method. Results: Two hundred twenty-nine cases were observed in the community-acquired sepsis (CAS) group and 79 cases in the hospital-acquired sepsis (HAS) group. In comparison with conventional culture, mNGS showed a significantly higher rate of positivity in both the CAS group (88.21% vs. 25.76%, adj.P < 0.001) and the HAS group (87.34% vs. 44.30%, adj.P < 0.001), particularly across various infection sites and specimens, which were not influenced by factors like antibiotic exposure or the timing and frequency of mNGS technology. Sepsis pathogens detected by mNGS were broad, especially viruses, Mycobacterium tuberculosis, and atypical pathogens, with mixed pathogens being common, particularly bacterial-viral co-detection. Based on the optimization of antimicrobial therapy using mNGS, 58 patients underwent antibiotic de-escalation, two patients were switched to antiviral therapy, and 14 patients initiated treatment for tuberculosis, resulting in a reduction in antibiotic overuse but without significant impact on sepsis prognosis. The HAS group exhibited a critical condition, poor prognosis, high medical expenses, and variations in etiology, yet the mNGS results did not result in increased medical costs for either group. Conclusions: mNGS demonstrates efficacy in identifying multiple pathogens responsible for sepsis, with mixed pathogens of bacteria and viruses being prevalent. Variability in microbiological profiles among different infection setting underscores the importance of clinical vigilance. Therefore, the adoption of mNGS for microbiological diagnosis of sepsis warrants acknowledgment and promotion.

12.
Microb Cell Fact ; 23(1): 113, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38622698

RESUMEN

BACKGROUND: Isatropolone A and C, produced by Streptomyces sp. CPCC 204095, belong to an unusual class of non-benzenoid aromatic compounds and contain a rare seven-membered ring structure. Isatropolone A exhibits potent activity against Leishmania donovani, comparable to the only oral drug miltefosine. However, its variably low productivity represents a limitation for this lead compound in the future development of new anti-leishmaniasis drugs to meet unmet clinical needs. RESULTS: Here we first elucidated the regulatory cascade of biosynthesis of isatropolones, which consists of two SARP family regulators, IsaF and IsaJ. Through a series of in vivo and in vitro experiments, IsaF was identified as a pathway-specific activator that orchestrates the transcription of the gene cluster essential for isatropolone biosynthesis. Interestingly, IsaJ was found to only upregulate the expression of the cytochrome P450 monooxygenase IsaS, which is crucial for the yield and proportion of isatropolone A and C. Through targeted gene deletions of isaJ or isaS, we effectively impeded the conversion of isatropolone A to C. Concurrently, the facilitation of isaF overexpression governed by selected promoters, prompted the comprehensive activation of the production of isatropolone A. Furthermore, meticulous optimization of the fermentation parameters was conducted. These strategies culminated in the attainment of an unprecedented maximum yield-980.8 mg/L of isatropolone A-achieved in small-scale solid-state fermentation utilizing the genetically modified strains, thereby establishing the highest reported titer to date. CONCLUSION: In Streptomyces sp. CPCC 204095, the production of isatropolone A and C is modulated by the SARP regulators IsaF and IsaJ. IsaF serves as a master pathway-specific regulator for the production of isatropolones. IsaJ, on the other hand, only dictates the transcription of IsaS, the enzyme responsible for the conversion of isatropolone A and C. By engineering the expression of these pivotal genes, we have devised a strategy for genetic modification aimed at the selective and high-yield biosynthesis of isatropolone A. This study not only unveils the unique regulatory mechanisms governing isatropolone biosynthesis for the first time, but also establishes an essential engineering framework for the targeted high-level production of isatropolone A.


Asunto(s)
Streptomyces , Streptomyces/metabolismo , Vías Biosintéticas/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Regiones Promotoras Genéticas , Familia de Multigenes
13.
J Phys Chem Lett ; 15(10): 2815-2824, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38441004

RESUMEN

Understanding the structural evolution of single-atom catalysts (SACs) in catalytic reactions is crucial for unraveling their catalytic mechanisms. In this study, we utilize density functional theory calculations to delve into the active phase evolution and the oxygen reduction reaction (ORR) mechanism of tungsten semicarbide-based transition metal SACs (TM1/W2C). The stable crystal phases and optimal surface exposures of W2C are identified by using ab initio atomistic thermodynamics simulations. Focusing on the W-terminated (001) surface, we screen 13 stable TM1/W2C variants, ultimately selecting Pt1/W2C(001) as our primary model. The surface Pourbaix diagram, mapped for this model under ORR conditions, reveals dynamic Pt1 migration on the surface, triggered by surface oxidation. This discovery suggests a novel single-atom evolution pathway. Remarkably, this single-atom migration behavior is also discerned in seven other group VIII SACs, enhancing both their catalytic activity and their stability. Our findings offer insights into the evolution of active phases in SACs, considering substrate structural arrangement, single-atom incorporation, and self-optimization of catalysts under various conditions.

14.
Int J Biol Macromol ; 265(Pt 1): 130966, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38508546

RESUMEN

Bamboo, featuring fast growth rate and high cellulose content, is considered to be one of the most attractive feedstocks for degradable bio-materials as a substitute for plastics. However, those was limited to the fields of bamboo structural materials mainly by physical processes. Herein, we report a facile continuous wet extrusion strategy for scalable manufacturing of anisotropic regenerated cellulose films in alkali/urea aqueous solution for the first time. The bamboo cellulose solution was regenerated in H2SO4/Na2SO4/ZnSO4 aqueous solution to facilitate the construction of dense fibrils networks. Moreover, under the synergistic effect of shear orientations and stretching processes in wet extrusion molding, the cellulose networks promoted further orientated assembly into aligned fibrils. Therefore, these anisotropic cellulose hydrogels exhibited good mechanical properties, and the tensile strength was increased from 1.67 MPa of anisotropic cellulose hydrogel with 1.0 of stretching ration (ACH-1.0) to 2.13 MPa of ACH-1.4 with increasing stretching ratio from 1.0 to 1.4, which was about 1.34 times higher than that of the isotropic hydrogel fabricated by tape-casting. Moreover, ACH-1.4 exhibited commendable thermal stability and air barrier properties. This work demonstrated a simple and continuous bottom-up approach for fabrication of anisotropic bamboo-based cellulose hydrogels and films with excellent mechanical properties.


Asunto(s)
Celulosa , Agua , Celulosa/química , Resistencia a la Tracción , Hidrogeles
15.
Transplant Rev (Orlando) ; 38(2): 100840, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38489866

RESUMEN

BACKGROUND: Current guidelines lack consensus on whether antiviral prophylaxes should be administered after kidney transplantation from HBcAb+ donors. This systematic review and meta-analysis aimed to evaluate the incidence and risk factors of de novo HBV (DNH) infection, as well as graft and patient survival. METHODS: We searched PubMed, Embase, and the Cochrane Library up to December 31, 2023. We included relevant studies that assessed clinical outcomes following transplantation utilizing HBcAb+ kidneys. Summary measures of effect and 95% confidence intervals (CI) for prevalence, risk factors, as well as graft and patient survival were estimated using random-effects meta-analysis. RESULTS: Thirteen studies were included for the final analysis. The DNH incidence was at 0.36% (9/2516) with low heterogeneity (I2 = 6%). HBsAb+ recipients (OR: 0.78, 95%CI: 0.25-2.38), HBcAb+ recipients (OR: 3.11, 95%CI: 0.91-10.66, P = 0.071), and recipients not receiving any antiviral prophylaxis (OR: 1.26, 95%CI: 0.15-10.58) were not associated with higher DNH risk. Specifically, HBsAb-/HBcAb+ recipients had the highest DNH incidence (4.65%), followed by HBsAb-/HBcAb- (0.49%), HBsAb+/HBcAb- recipients (0.45%), and HBsAb+/HBcAb+ (0%). Furthermore, recipients receiving HBcAb+ kidneys had comparable graft survival (HR: 1.06, 95%CI: 0.94-1.19, P = 0.55) and patient survival (HR:1.16, 95%CI: 0.98-1.38, P = 0.090) compared with recipients receiving HBcAb- kidneys. CONCLUSION: Kidney transplantation utilizing HBcAb+ kidneys contributed to comparable graft and patient survival with an extremely low risk of HBV transmission. Antiviral prophylaxes may only be administered in HBsAb-/HBcAb+ recipients.


Asunto(s)
Trasplante de Riñón , Trasplante de Hígado , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Hígado/efectos adversos , Antígenos del Núcleo de la Hepatitis B , Donantes de Tejidos , Anticuerpos contra la Hepatitis B , Antivirales/uso terapéutico
16.
Heliyon ; 10(6): e27740, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38515674

RESUMEN

This review critically examines the progress and challenges in the field of nanostructured tungsten oxide (WO3) gas sensors. It delves into the significant advancements achieved through nanostructuring and composite formation of WO3, which have markedly improved sensor sensitivity for gases like NO2, NH3, and VOCs, achieving detection limits in the ppb range. The review systematically explores various innovative approaches, such as doping WO3 with transition metals, creating heterojunctions with materials like CuO and graphene, and employing machine learning models to optimize sensor configurations. The challenges facing WO3 sensors are also thoroughly examined. Key issues include cross-sensitivity to different gases, particularly at higher temperatures, and long-term stability affected by factors like grain growth and volatility of dopants. The review assesses potential solutions to these challenges, including statistical analysis of sensor arrays, surface functionalization, and the use of novel nanostructures for enhanced performance and selectivity. In addition, the review discusses the impact of ambient humidity on sensor performance and the current strategies to mitigate it, such as composite materials with humidity shielding effects and surface functionalization with hydrophobic groups. The need for high operating temperatures, leading to higher power consumption, is also addressed, along with possible solutions like the use of advanced materials and new transduction principles to lower temperature requirements. The review concludes by highlighting the necessity for a multidisciplinary approach in future research. This approach should combine materials synthesis, device engineering, and data science to develop the next generation of WO3 sensors with enhanced sensitivity, ultrafast response rates, and improved portability. The integration of machine learning and IoT connectivity is posited as a key driver for new applications in areas like personal exposure monitoring, wearable diagnostics, and smart city networks, underlining WO3's potential as a robust gas sensing material in future technological advancements.

17.
J Med Virol ; 96(3): e29454, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38445768

RESUMEN

Various vaccines have been challenged by SARS-CoV-2 variants. Here, we reported a yeast-derived recombinant bivalent vaccine (Bivalent wild-type [Wt]+De) based on the wt and Delta receptor-binding domain (RBD). Yeast derived RBD proteins based on the wt and Delta mutant were used as the prime vaccine. It was found that, in the presence of aluminium hydroxide (Alum) and unmethylated CpG-oligodeoxynucleotides (CpG) adjuvants, more cross-protective immunity against SARS-CoV-2 prototype and variants were elicited by bivalent vaccine than monovalent wtRBD or Delta RBD. Furthermore, a heterologous boosting strategy consisting of two doses of bivalent vaccines followed by one dose adenovirus vectored vaccine exhibited cross-neutralization capacity and specific T cell responses against Delta and Omicron (BA.1 and BA.4/5) variants in mice, superior to a homologous vaccination strategy. This study suggested that heterologous prime-boost vaccination with yeast-derived bivalent protein vaccine could be a potential approach to address the challenge of emerging variants.


Asunto(s)
COVID-19 , Vacunas , Animales , Ratones , Vacunas Combinadas , Proteínas Fúngicas , Saccharomyces cerevisiae/genética , COVID-19/prevención & control , SARS-CoV-2 , Vacunación
18.
Nat Nanotechnol ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448520

RESUMEN

Free radicals, generally formed through the cleavage of covalent electron-pair bonds, play an important role in diverse fields ranging from synthetic chemistry to spintronics and nonlinear optics. However, the characterization and regulation of the radical state at a single-molecule level face formidable challenges. Here we present the detection and sophisticated tuning of the open-shell character of individual diradicals with a donor-acceptor structure via a sensitive single-molecule electrical approach. The radical is sandwiched between nanogapped graphene electrodes via covalent amide bonds to construct stable graphene-molecule-graphene single-molecule junctions. We measure the electrical conductance as a function of temperature and track the evolution of the closed-shell and open-shell electronic structures in real time, the open-shell triplet state being stabilized with increasing temperature. Furthermore, we tune the spin states by external stimuli, such as electrical and magnetic fields, and extract thermodynamic and kinetic parameters of the transition between closed-shell and open-shell states. Our findings provide insights into the evolution of single-molecule radicals under external stimuli, which may proof instrumental for the development of functional quantum spin-based molecular devices.

19.
Nano Lett ; 24(11): 3462-3469, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38451166

RESUMEN

Two-dimensional (2D) room-temperature multiferroic materials are highly desirable but still very limited. Herein, we propose a potential strategy to obtain such materials in 2D metal-organic frameworks (MOFs) by utilizing the d-p direct spin coupling in conjunction with center-symmetry-breaking six-membered heterocyclic rings. Based on this strategy, a screening of 128 2D MOFs results in the identification of three multiferroics, that is, Cr(1,2-oxazine)2, Cr(1,2,4-triazine)2, and Cr(1,2,3,4-trazine)2, simultaneously exhibiting room-temperature ferrimagnetism and ferroelectricity/antiferroelectricity. The room-temperature ferrimagnetic order (306-495 K) in these MOFs originates from the strong d-p direct magnetic exchange interaction between Cr cations and ligand anions. Specifically, Cr(1,2-oxazine)2 exhibits ferroelectric behavior with an out-of-plane polarization of 4.24 pC/m, whereas the other two manifest antiferroelectric characteristics. Notably, all three materials present suitable polarization switching barriers (0.18-0.31 eV). Furthermore, these MOFs are all bipolar magnetic semiconductors with moderate band gaps, in which the spin direction of carriers can be manipulated by electrical gating.

20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(2): 145-150, 2024 Feb 15.
Artículo en Chino | MEDLINE | ID: mdl-38385225

RESUMEN

Objective: To analyze the effect of stump-preserving repair on rotator cuff healing and shoulder function for degenerative total rotator cuff tears. Methods: A clinical data of 152 patients with degenerative total rotator cuff tears, who underwent arthroscopic repair between April 2019 and May 2022, was retrospectively analyzed. There were 76 males and 76 females with an average age of 55.4 years (range, 24-78 years). MRI was performed at 6 months postoperatively to evaluate the rotator cuff healing according to the Sugaya classification. Pre- and intra-operative related factors were included for univariate analysis, including age (≥60 years/<60 years), gender (male/female), passive activity disorder (yes/no), disease duration (≤3 months/>3 months), stump-preserving repair (yes/no), use of suture bridge technique (yes/no), shoulder joint abduction angle at knotting (<45°/≥45°), acromioplasty (yes/no), glucocorticoid injection (yes/no), time for patients to start postoperative passive exercise (≤2 weeks/>2 weeks), and time for patients to start postoperative active exercise (≤3 months/>3 months). The influencing factors of tendon healing were screened; further logistic regression was used to conduct multivariate analysis to screen for risk factors. Two sets of data were balanced by propensity score matching. The American Shoulder and Elbow Surgeons (ASES) score and Constant-Murley score of shoulder joint function at 6 and 12 months postoperatively, as well as rotator cuff healing rate at 6 months postoperatively, were compared between groups based on whether or not stump-preserving repair was used. Results: All patients were followed up 12-33 months (mean, 23.8 months). MRI at 25-31 weeks postoperatively showed the 121 cases of rotator cuff healing and 31 cases of non healing. Univariate analysis showed that the disease duration, stump-preserving repair, shoulder joint abduction angle at knotting, and the time for patients to start postoperative active exercise were the influencing factors of rotator cuff healing ( P<0.05). Multivariate analysis showed that non-stump-preserving repair, shoulder abduction angle more than 45° at knotting, and the time to start active exercise within 3 months postoperatively were risk factors affecting rotator cuff healing ( P<0.05). A total of 51 pairs of cases were matched based on the grouping criteria of whether the disease duration exceeded 3 months, whether the shoulder abduction angle at knotting exceeded 45°, and whether the time to start postoperative active exercise exceeded 3 months. The rotator cuff healing rate, ASES score, and Constant-Murley score of the preserving repair group at 6 months postoperatively were superior to those of the non-preserving repair group, and the differences were significant ( P<0.05). There was no significant difference in ASES score and Constant-Murley score between the two groups at 12 months postoperatively ( P>0.05). Conclusion: For degenerative total rotator cuff tears, the stump-preserving repair can shorten the healing time and promote the shoulder function recovery, but has no significant effect on shoulder function at 1 year postoperatively.


Asunto(s)
Lesiones del Manguito de los Rotadores , Articulación del Hombro , Humanos , Femenino , Masculino , Persona de Mediana Edad , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/cirugía , Hombro , Estudios Retrospectivos , Resultado del Tratamiento , Artroscopía/métodos , Articulación del Hombro/cirugía , Imagen por Resonancia Magnética , Rango del Movimiento Articular
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