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1.
Front Pharmacol ; 15: 1405342, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38953103

RESUMO

Angelica sinensis is a long-standing medicine used by Chinese medical practitioners and well-known for its blood-tonic and blood-activating effects. Ferulic acid, ligustilide, and eugenol in Angelica sinensis activate the blood circulation; however, the material basis of their blood-tonic effects needs to be further investigated. In this study, five homogeneous Angelica sinensis polysaccharides were isolated, and their sugar content, molecular weight, monosaccharide composition, and infrared characteristics determined. Acetylphenylhydrazine (APH) and cyclophosphamide (CTX) were used as inducers to establish a blood deficiency model in mice, and organ indices, haematological and biochemical parameters were measured in mice. Results of in vivo hematopoietic activity showed that Angelica sinensis polysaccharide (APS) could elevate erythropoietin (EPO), granulocyte colony-stimulating factor (G-CSF), and interleukin-3 (IL-3) serum levels, reduce tumor necrosis factor-α (TNF-α) level in mice, and promote hematopoiesis in the body by regulating cytokine levels. Biological potency test results of the in vitro blood supplementation indicated strongest tonic activity for APS-H2O, and APS-0.4 has the weakest haemopoietic activity. The structures of APS-H2O and APS-0.4 were characterized, and the results showed that APS-H2O is an arabinogalactan glycan with a main chain consisting of α-1,3,5-Ara(f), α-1,5- Ara(f), ß-1,4-Gal(p), and ß-1,4-Gal(p)A, and two branched chains of ß-t-Gal(p) and α-t-Glc(p) connected to each other in a (1→3) linkage to α-1,3,5-Ara(f) on the main chain. APS-0.4 is an acidic polysaccharide with galacturonic acid as the main chain, consisting of α-1,4-GalA, α-1,2-GalA, α-1,4-Gal, and ß-1,4-Rha. In conclusion, APS-H2O can be used as a potential drug for blood replenishment in patients with blood deficiency, providing a basis for APS application in clinical treatment and health foods, as well as research and development of new polysaccharide-based drugs.

2.
Neural Netw ; 178: 106483, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38954893

RESUMO

In reinforcement learning, accurate estimation of the Q-value is crucial for acquiring an optimal policy. However, current successful Actor-Critic methods still suffer from underestimation bias. Additionally, there exists a significant estimation bias, regardless of the method used in the critic initialization phase. To address these challenges and reduce estimation errors, we propose CEILING, a simple and compatible framework that can be applied to any model-free Actor-Critic methods. The core idea of CEILING is to evaluate the superiority of different estimation methods by incorporating the true Q-value, calculated using Monte Carlo, during the training process. CEILING consists of two implementations: the Direct Picking Operation and the Exponential Softmax Weighting Operation. The first implementation selects the optimal method at each fixed step and applies it in subsequent interactions until the next selection. The other implementation utilizes a nonlinear weighting function that dynamically assigns larger weights to more accurate methods. Theoretically, we demonstrate that our methods provide a more accurate and stable Q-value estimation. Additionally, we analyze the upper bound of the estimation bias. Based on two implementations, we propose specific algorithms and their variants, and our methods achieve superior performance on several benchmark tasks.

3.
Redox Biol ; 75: 103260, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38955114

RESUMO

Tumor metabolic reprogramming requires high levels of adenosine triphosphate (ATP) to maintain treatment resistance, which poses major challenges to chemotherapy and photothermal therapy. Especially, high levels of ATP promote copper ion efflux for limiting the curative effect of cuproptosis. Here, an H2S-responsive mesoporous Cu2Cl(OH)3-loading chemotherapeutic cisplatin (CDDP) was synthesized, and the final nanoparticle, CDDP@Cu2Cl(OH)3-CDs (CDCuCDs), was encapsulated by electrostatic action with carbon dots (CDs). CDCuCDs reacted with overproduction H2S in colon tumor to produce photothermic copper sulfide for photothermal therapy. CDDP was released by lysis to achieve chemotherapeutic effects. Importantly, CDDP elevated H2O2 levels in cells through a cascade reaction and continuously transforms H2O2 into highly cytotoxic •OH through chemodynamic therapy between H2O2 and Cu+, which enables nanoparticles to generate •OH and improve the chemotherapeutic efficacy. Highly toxic •OH disrupts mitochondrial homeostasis, prohibiting it from performing normal energy-supplying functions. Down-regulated ATP inhibits heat shock protein expression, which promotes the therapeutic effect of mild photothermal therapy and reduces the efflux of intracellular copper ions, thus improving the therapeutic effect of cuproptosis. Our research provides a potential therapeutic strategy using overproduction H2S responses in tumors, allowing tumor microenvironment-activated •OH nanogenerators to promote tumor energy remodeling for cancer treatment.

4.
Nat Med ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956195

RESUMO

Recent single-arm studies involving neoadjuvant camrelizumab, a PD-1 inhibitor, plus chemotherapy for resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC) have shown promising results. This multicenter, randomized, open-label phase 3 trial aimed to further assess the efficacy and safety of neoadjuvant camrelizumab plus chemotherapy followed by adjuvant camrelizumab, compared to neoadjuvant chemotherapy alone. A total of 391 patients with resectable thoracic LA-ESCC (T1b-3N1-3M0 or T3N0M0) were stratified by clinical stage (I/II, III or IVA) and randomized in a 1:1:1 ratio to undergo two cycles of neoadjuvant therapy. Treatments included camrelizumab, albumin-bound paclitaxel and cisplatin (Cam+nab-TP group; n = 132); camrelizumab, paclitaxel and cisplatin (Cam+TP group; n = 130); and paclitaxel with cisplatin (TP group; n = 129), followed by surgical resection. Both the Cam+nab-TP and Cam+TP groups also received adjuvant camrelizumab. The dual primary endpoints were the rate of pathological complete response (pCR), as evaluated by a blind independent review committee, and event-free survival (EFS), as assessed by investigators. This study reports the final analysis of pCR rates. In the intention-to-treat population, the Cam+nab-TP and Cam+TP groups exhibited significantly higher pCR rates of 28.0% and 15.4%, respectively, compared to 4.7% in the TP group (Cam+nab-TP versus TP: difference 23.5%, 95% confidence interval (CI) 15.1-32.0, P < 0.0001; Cam+TP versus TP: difference 10.9%, 95% CI 3.7-18.1, P = 0.0034). The study met its primary endpoint of pCR; however, EFS is not yet mature. The incidence of grade ≥3 treatment-related adverse events during neoadjuvant treatment was 34.1% for the Cam+nab-TP group, 29.2% for the Cam+TP group and 28.8% for the TP group; the postoperative complication rates were 34.2%, 38.8% and 32.0%, respectively. Neoadjuvant camrelizumab plus chemotherapy demonstrated superior pCR rates compared to chemotherapy alone for LA-ESCC, with a tolerable safety profile. Chinese Clinical Trial Registry identifier: ChiCTR2000040034 .

5.
Artigo em Inglês | MEDLINE | ID: mdl-38956908

RESUMO

BACKGROUND: Evodiamine (EVO) is an alkaloid extracted from the dried and nearly ripe fruits of Euodia rutaecarpa and used as an anti-cancer, anti-inflammatory and anti-obesity agent. However, robust evidence of preclinical experiments has been lacking so far. Therefore, the purpose of this article was to investigate the effect of EVO in combination with other treatments on tumors in animal experiments. METHODS: A systematic review and meta-analysis were conducted to assess the anti-tumor effect of evodiamine-combined therapy. The search engine and electronic databases included PubMed, Scopus, China Knowledge Resource Integrated Database (CNKI), and SinoMed. The research method was based on the PRISMA checklist. RESULTS: A total of 7 studies and 108 animals were included. As a result, EVO combined therapy was found to be more effective than EVO monotherapy. The SMD was -25.64(95% CI: -5.77 -3.13) in tumor growth. In tumor weight, the SMD was -8.91(95% CI: -16.37, -1.44). CONCLUSION: EVO has the potential to alleviate the toxicity of chemotherapeutic agents, which increases the translatability to the clinical situation.

6.
Autophagy ; : 1-18, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38964379

RESUMO

Macroautophagic/autophagic and endocytic pathways play essential roles in maintaining homeostasis at different levels. It remains poorly understood how both pathways are coordinated and fine-tuned for proper lysosomal degradation of diverse cargoes. We and others recently identified a Golgi-resident RAB GTPase, RAB2A, as a positive regulator that controls both autophagic and endocytic pathways. In the current study, we report that TBC1D4 (TBC1 domain family member 4), a TBC domain-containing protein that plays essential roles in glucose homeostasis, suppresses RAB2A-mediated autophagic and endocytic pathways. TBC1D4 bound to RAB2A through its N-terminal PTB2 domain, which impaired RAB2A-mediated autophagy at the early stage by preventing ULK1 complex activation. During the late stage of autophagy, TBC1D4 impeded the association of RUBCNL/PACER and RAB2A with STX17 on autophagosomes by direct interaction with RUBCNL via its N-terminal PTB1 domain. Disruption of the autophagosomal trimeric complex containing RAB2A, RUBCNL and STX17 resulted in defective HOPS recruitment and eventually abortive autophagosome-lysosome fusion. Furthermore, TBC1D4 inhibited RAB2A-mediated endocytic degradation independent of RUBCNL. Therefore, TBC1D4 and RAB2A form a dual molecular switch to modulate autophagic and endocytic pathways. Importantly, hepatocyte- or adipocyte-specific tbc1d4 knockout in mice led to elevated autophagic flux and endocytic degradation and tissue damage. Together, this work establishes TBC1D4 as a critical molecular brake in autophagic and endocytic pathways, providing further mechanistic insights into how these pathways are intertwined both in vitro and in vivo.Abbreviations: ACTB: actin beta; ATG9: autophagy related 9; ATG14: autophagy related 14; ATG16L1: autophagy related 16 like 1; CLEM: correlative light electron microscopy; Ctrl: control; DMSO: dimethyl sulfoxide; EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; FL: full length; GAP: GTPase-activating protein; GFP: green fluorescent protein; HOPS: homotypic fusion and protein sorting; IP: immunoprecipitation; KD: knockdown; KO: knockout; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; OE: overexpression; PG: phagophore; PtdIns3K: class III phosphatidylinositol 3-kinase; SLC2A4/GLUT4: solute carrier family 2 member 4; SQSTM1/p62: sequestosome 1; RUBCNL/PACER: rubicon like autophagy enhancer; STX17: syntaxin 17; TAP: tandem affinity purification; TBA: total bile acid; TBC1D4: TBC1 domain family member 4; TUBA1B: tubulin alpha 1b; ULK1: unc-51 like autophagy activating kinase 1; VPS39: VPS39 subunit of HOPS complex; WB: western blot; WT: wild type.

7.
Perioper Med (Lond) ; 13(1): 68, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970081

RESUMO

BACKGROUND: High doses of long-acting opioids were used to facilitate off-pump coronary artery bypass grafting procedure, which may result in opioid-related adverse events after surgery. Transcutaneous electrical acupoint stimulation (TEAS) had been reported to be effective in reducing intraoperative opioids consumption during surgery. The aim of this study is to assess whether TEAS with difference acupoints can reduce the doses of opioid analgesics. METHODS: This was a multicenter, randomized, controlled, double-blind trial. Patients underwent off-pump coronary artery bypass grafting under general anesthesia were enrolled. Eligible patients were randomly and equally grouped into sham acupuncture group (n = 105), regional acupoints combination group (n = 105), or distal-proximal acupoints combination group (n = 105) using a centralized computer-generated randomization system. Transcutaneous electrical acupoint stimulation was applied for 30 min before anesthesia induction. The primary outcome was the doses of sufentanil during anesthesia. Secondary outcomes included the highest postoperative vasoactive-inotropic scores within 24 h, intraoperative propofol consumption, length of mechanical ventilation, duration of cardiac care unit and postoperative hospital stay, incidence of postoperative complications, and mortality within 30 days after surgery. RESULTS: Of the 315 randomized patients, 313 completed the trial. In the modified intention-to-treat analysis, the doses of sufentanil were 303.9 (10.8) µg in the distal-proximal acupoints group, significantly lower than the sham group, and the mean difference was - 34.9 (- 64.9 to - 4.9) µg, p = 0.023. The consumption of sufentanil was lower in distal-proximal group than regional group (303.9 vs. 339.5), and mean difference was - 35.5 (- 65.6 to - 5.5) µg, p = 0.020. The distal-proximal group showed 10% reduction in opioids consumption comparing to both regional and sham groups. Secondary outcomes were comparable among three groups. CONCLUSION: Transcutaneous electrical acupoint stimulation with distal-proximal acupoints combination, compared to regional acupoints combination and sham acupuncture, significantly reduced sufentanil consumption in patients who underwent off-pump coronary artery bypass grafting surgery.

9.
Waste Manag ; 187: 22-30, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971024

RESUMO

The widespread use of plastic mulch film (PMF) has led to significant environmental pollution, with PMF residues dispersed and mixed with straw and soil, posing challenges for recycling. Here, we proposed the mobile pyrolysis facility for the cotton straw and mulch film mixture (CMM) to mitigate the collection, storage, and transportation costs, while the application of co-pyrolysis technology for CMM conversion could improve the added value of products. Additionally, centralized combustion power generation and centralized pyrolysis systems were also established to evaluate and compare their sustainability from economic and environmental perspectives. Results showed that mobile pyrolysis has better economic performance than the centralized scenarios, due to its high internal rate of return (31 %) and significant net present value (29.21 M USD). Meanwhile, the mobile pyrolysis facility achieved a GWP of -1.298 kgCO2-eq/kg, reducing emissions by 70.79 % and 38.82 % compared to the two centralized scenarios. In conclusion, mobile pyrolysis technology provides a promising solution for PMF residue recycling because of its economically competitive approach with a lower carbon footprint.

10.
Nat Commun ; 15(1): 5613, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965236

RESUMO

Advancements in CRISPR technology, particularly the development of base editors, revolutionize genetic variant research. When combined with model organisms like zebrafish, base editors significantly accelerate and refine in vivo analysis of genetic variations. However, base editors are restricted by protospacer adjacent motif (PAM) sequences and specific editing windows, hindering their applicability to a broad spectrum of genetic variants. Additionally, base editors can introduce unintended mutations and often exhibit reduced efficiency in living organisms compared to cultured cell lines. Here, we engineer a suite of adenine base editors (ABEs) called ABE-Ultramax (Umax), demonstrating high editing efficiency and low rates of insertions and deletions (indels) in zebrafish. The ABE-Umax suite of editors includes ABEs with shifted, narrowed, or broadened editing windows, reduced bystander mutation frequency, and highly flexible PAM sequence requirements. These advancements have the potential to address previous challenges in disease modeling and advance gene therapy applications.


Assuntos
Adenina , Sistemas CRISPR-Cas , Edição de Genes , Mutação INDEL , Peixe-Zebra , Peixe-Zebra/genética , Animais , Edição de Genes/métodos , Adenina/metabolismo , RNA Guia de Sistemas CRISPR-Cas/genética , RNA Guia de Sistemas CRISPR-Cas/metabolismo , Animais Geneticamente Modificados , Alelos
11.
Sci Rep ; 14(1): 15403, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965327

RESUMO

Cut vertices and cut edges are valuable for analyzing connectivity problems in classical graph theory. However, they cannot deal with certain fuzzy problems. In order to solve this problem, this paper introduces the definitions of fuzzy strong cut vertices and fuzzy strong cut edges, and characterizes fuzzy strong cut vertices and fuzzy strong cut edges in fuzzy trees, complete fuzzy graphs, and fuzzy cycles. Finally, practical applications verify the effectiveness of the theory in network stability analysis.

12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(7): 821-824, 2024 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-38946365

RESUMO

OBJECTIVE: To explore the genetic basis for a child featuring facial dysmorphism and intellectual disabilities. METHODS: A child who was diagnosed at Linyi People's Hospital on January 5 2023 due to "mental retardation" was selected as the study subject. Peripheral blood samples of the child and his parents, in addition with an amniotic fluid sample from the his mother were collected for the extraction of genomic DNA. Whole exome sequencing was carried out for the child, and candidate variant was verified by Sanger sequencing of his family members. RESULTS: The child was found to harbor a hemizygous c.1123dupG (p.E375Gfs*4) variant of the NEXMIF gene, for which both of his parents and the fetus were of the wild type. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic (PVS1+PS2-P+PM2-P). A healthy infant was subsequently born. CONCLUSION: The hemizygous c.1123dupG (p.E375Gfs*4) variant of the NEXMIF gene probably underlay the disease in this child. Based on his clinical phenotype and genotype, the child was ultimately diagnosed with X-linked intellectual developmental disorder-98. Above finding has also enriched the mutational spectrum of the NEXMIF gene.


Assuntos
Deficiência Intelectual , Humanos , Masculino , Deficiência Intelectual/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Mutação , Sequenciamento do Exoma , Testes Genéticos , Feminino , Criança , Linhagem , Lactente , Pré-Escolar , Proteínas do Tecido Nervoso
13.
Nat Commun ; 15(1): 5513, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951497

RESUMO

The second-order nonlinear Hall effect (NLHE) in non-centrosymmetric materials has recently drawn intense interest, since its inherent rectification could enable various device applications such as energy harvesting and wireless charging. However, previously reported NLHE systems normally suffer from relatively small Hall voltage outputs and/or low working temperatures. In this study, we report the observation of a pronounced NLHE in tellurium (Te) thin flakes at room temperature. Benefiting from the semiconductor nature of Te, the obtained nonlinear response can be readily enhanced through electrostatic gating, leading to a second-harmonic output at 300 K up to 2.8 mV. By utilizing such a giant NLHE, we further demonstrate the potential of Te as a wireless Hall rectifier within the radiofrequency range, which is manifested by the remarkable and tunable rectification effect also at room temperature. Extrinsic scattering is then revealed to be the dominant mechanism for the NLHE in Te, with symmetry breaking on the surface playing a key role. As a simple elemental semiconductor, Te provides an appealing platform to advance our understanding of nonlinear transport in solids and to develop NLHE-based electronic devices.

14.
Sci Rep ; 14(1): 15009, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951638

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with intricate pathogenesis and varied presentation. Accurate diagnostic tools are imperative to detect and manage UC. This study sought to construct a robust diagnostic model using gene expression profiles and to identify key genes that differentiate UC patients from healthy controls. Gene expression profiles from eight cohorts, encompassing a total of 335 UC patients and 129 healthy controls, were analyzed. A total of 7530 gene sets were computed using the GSEA method. Subsequent batch correction, PCA plots, and intersection analysis identified crucial pathways and genes. Machine learning, incorporating 101 algorithm combinations, was employed to develop diagnostic models. Verification was done using four external cohorts, adding depth to the sample repertoire. Evaluation of immune cell infiltration was undertaken through single-sample GSEA. All statistical analyses were conducted using R (Version: 4.2.2), with significance set at a P value below 0.05. Employing the GSEA method, 7530 gene sets were computed. From this, 19 intersecting pathways were discerned to be consistently upregulated across all cohorts, which pertained to cell adhesion, development, metabolism, immune response, and protein regulation. This corresponded to 83 unique genes. Machine learning insights culminated in the LASSO regression model, which outperformed others with an average AUC of 0.942. This model's efficacy was further ratified across four external cohorts, with AUC values ranging from 0.694 to 0.873 and significant Kappa statistics indicating its predictive accuracy. The LASSO logistic regression model highlighted 13 genes, with LCN2, ASS1, and IRAK3 emerging as pivotal. Notably, LCN2 showcased significantly heightened expression in active UC patients compared to both non-active patients and healthy controls (P < 0.05). Investigations into the correlation between these genes and immune cell infiltration in UC highlighted activated dendritic cells, with statistically significant positive correlations noted for LCN2 and IRAK3 across multiple datasets. Through comprehensive gene expression analysis and machine learning, a potent LASSO-based diagnostic model for UC was developed. Genes such as LCN2, ASS1, and IRAK3 hold potential as both diagnostic markers and therapeutic targets, offering a promising direction for future UC research and clinical application.


Assuntos
Colite Ulcerativa , Aprendizado de Máquina , Humanos , Colite Ulcerativa/genética , Colite Ulcerativa/diagnóstico , Algoritmos , Perfilação da Expressão Gênica/métodos , Transcriptoma , Quinases Associadas a Receptores de Interleucina-1/genética , Masculino , Feminino , Lipocalina-2/genética , Estudos de Casos e Controles , Biomarcadores , Adulto
15.
Sci Rep ; 14(1): 15122, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956289

RESUMO

Natalisin (NTL) is a conserved neuropeptide, only present in insects, that has been reported to regulate their sexual activity. In this study, we investigated the involvement of NTL in the reproductive behaviors of a major invasive pest, Spodoptera frugiperda. We identified NTL precursor-encoded transcripts, and evaluated their transcript levels in different stages and tissues of S. frugiperda. The results showed that the NTL transcript level was expressed in both male and female pupae and both male and female adults in the later stage. It was highly expressed in male pupae, 3-day-old male and female adults, and 5-day-old male adults. In different tissues, the expression level is higher in the male and female adult brain and male testis. Immunohistochemical staining of the brain of S. frugiperda female and male adults revealed that three pairs of brain neurons of S. frugiperda adults of both sexes secreted and expressed NTL. To study the role of NTL in reproductive behaviors, NTL was silenced in S. frugiperda male and female adults by RNA interference (RNAi) technology, the results showed that silencing NTL could significantly affect the sexual activity behavior of the adults, reducing the calling rate of females, the courtship rate of males, and the mating rate. In summary, this study emphasizes the important role of NTL in regulating the mating behavior and sexual activity of S. frugiperda in both male and female adults, potentially laying a foundation to employ NTL as a new insect-specific target to control populations of pest insects.


Assuntos
Neuropeptídeos , Comportamento Sexual Animal , Spodoptera , Animais , Spodoptera/genética , Spodoptera/fisiologia , Masculino , Feminino , Neuropeptídeos/metabolismo , Neuropeptídeos/genética , Comportamento Sexual Animal/fisiologia , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Encéfalo/metabolismo , Interferência de RNA , Reprodução
16.
Small ; : e2402317, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38988143

RESUMO

Here, the poly (l-lactic acid) (PLLA) membrane with multi-structured networks (MSN) is successfully prepared by electrospinning technology for the first time. It is composed of micron-sized ribbon-structured fibers and ultrafine nanofibers with a diameter of tens of nanometers, and they are connected to form the new network structure. Thanks to the special fiber morphology and structure, the interception and electrostatic adsorption ability for against atmospheric particulate matter (PM) are significantly enhanced, and the resistance to airflow is reduced due to the "slip effect" caused by ultrafine nanofibers. The PLLA MSN membrane shows excellent filtration performance with ultra-high filtration efficiency (>99.9% for PM2.5 and >99.5% for PM0.3) and ultra-low pressure drop (≈20 Pa). It has demonstrated filtration performance that even exceeds current non-biodegradable polymer materials, laying the foundation for future applications of biodegradable PLLA in the field of air filtration. In addition, this new structure also provides a new idea for optimizing the performance of other polymer materials.

17.
Anal Chem ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989981

RESUMO

Exploring the high-performance photoelectronic properties of perovskite quantum dots (QDs) is desirable for paper-based photoelectrochemical (PEC) sensing;however, challenges remain in improving their stability and fundamental performance. Herein, a novel Z-scheme heterostructure with host-guest interaction by the confinement of CH3NH3PbBr3 QDs within Cu3(BTC)2 metal-organic framework (MOF) crystal (MAPbBr3@Cu3(BTC)2) is successfully constructed on the paper-based PEC device for ultrasensitive detection of Ochratoxin A (OTA), with the assistance of the exciton-plasmon interaction (EPI) effect. The host-guest interaction is estabilished by encapsulating MAPbBr3 QDs as guests within Cu3(BTC)2 MOF as a host, which prevents MAPbBr3 QDs from being damaged in the polar system, offering access to long-term stability with high-performance PEC properties. Benefiting from the precise alignment of energy levels, the photogenerated charge carriers can migrate according to the Z-scheme charge-transfer pathway under the driving force of the internal electric field, achieving a high photoelectric conversion efficiency. Upon OTA recognition, the EPI effect is activated to modulate the exciton response in MAPbBr3 QDs by accelerating radiative decay, finally achieving sensitive OTA sensing with a detection limit of 0.017 pg mL-1. We believe this work renders new insight into designing host-guest Z-scheme heterojunctions in constructing the paper-based PEC sensing platforms for environmental monitoring.

18.
Anal Methods ; 16(27): 4644-4652, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38946403

RESUMO

In order to develop a highly efficient H2S gas sensor at low working temperature, in this work, a kind of novel Ce-doped ZnCo2O4 hollow microspheres (Ce/ZnCo2O4 HMSs) were successfully synthesized using a template-free one-pot method, showing a sensitive response toward H2S. The microstructure and morphology of the material were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The gas-sensing performance of the composite was investigated, showing that the ZnCo2O4 doped with 6 mol% Ce had the highest response to 20 ppm H2S at a low operating temperature of 160 °C with a response value of 67.42, which was about 2 times higher than that of original ZnCo2O4. The prepared Ce/ZnCo2O4 HMS sensor in response to H2S exhibited a linear range of 0.1-200 ppm with a low detection limit of 0.1 ppm under the conditions of ambient humidity of 45% and ambient temperature of 20 °C. Meanwhile, it also possessed good selectivity, repeatability and reproducibility. The response value of the sensor decreased by 5.32% after 7 months of continuous monitoring of H2S in an atmospheric environment of a pig farm, indicating that the sensor had a long-term stability and continuous service life with important application prospects.

19.
Hum Vaccin Immunother ; 20(1): 2370605, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38977415

RESUMO

The outbreak of the COVID-19 has seriously affected the whole society, and vaccines were the most effective means to contain the epidemic. This paper aims to determine the top 100 articles cited most frequently in COVID-19 vaccines and to analyze the research status and hot spots in this field through bibliometrics, to provide a reference for future research. We conducted a comprehensive search of the Web of Science Core Collection database on November 29, 2023, and identified the top 100 articles by ranking them from highest to lowest citation frequency. In addition, we analyzed the year of publication, citation, author, country, institution, journal, and keywords with Microsoft Excel 2019 and VOSviewer 1.6.18. Research focused on vaccine immunogenicity and safety, vaccine hesitancy, and vaccination intention.


Assuntos
Bibliometria , Vacinas contra COVID-19 , COVID-19 , Humanos , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/epidemiologia , SARS-CoV-2/imunologia , Vacinação/estatística & dados numéricos , Hesitação Vacinal/estatística & dados numéricos , Imunogenicidade da Vacina
20.
Org Lett ; 26(27): 5625-5629, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38953484

RESUMO

A palladium-catalyzed cascade carbonylation reaction of 2-bromo-N-(2-iodophenyl)benzamides with benzylidenecyclopropanes for the synthesis of fused isoindolinone derivatives has been developed. A broad range of 6/5/6/6 tetracyclic isoindolinone products were efficiently prepared in moderate to good yields with diverse substitution. Two carbonyl groups were incorporated into the substrates in a single step with the formation of four carbon-carbon bonds and two carbon-heteroatom bonds.

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