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1.
Nano Lett ; 24(22): 6821-6827, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787786

RESUMO

In the quasi-two-dimensional superconductor NbSe2, the superconducting transition temperature (Tc) is layer-dependent, decreasing by about 60% in the monolayer limit. However, for the extremely anisotropic copper-based high-Tc superconductor Bi2Sr2CaCu2O8+δ (Bi-2212), the Tc of the monolayer is almost identical with that of its bulk counterpart. To clarify the effect of dimensionality on superconductivity, here, we successfully fabricate ultrathin flakes of iron-based high-Tc superconductors CsCa2Fe4As4F2 and CaKFe4As4. It is found that the Tc of monolayer CsCa2Fe4As4F2 (after tuning to the optimal doping by ionic liquid gating) is about 20% lower than that of the bulk crystal, while the Tc of three-layer CaKFe4As4 decreases by 46%, showing a more pronounced dimensional effect than that of CsCa2Fe4As4F2. By carefully examining their anisotropy and the c-axis coherence length, we reveal the general trend and empirical law of the layer-dependent superconductivity in these quasi-two-dimensional superconductors.

2.
Med Sci Monit ; 30: e944063, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875178

RESUMO

BACKGROUND This prospective study from a single center aimed to compare the perioperative blood loss (PBL) in 79 patients with intertrochanteric fractures (IF) treated with intramedullary nailing (IMN) using 3 regimens of combined tranexamic acid (TXA) and low molecular weight heparin (LMWH), proposing a novel therapy of 4-dose TXA. MATERIAL AND METHODS We recruited 79 patients and randomly divided them into 3 groups. The 4-dose TXA group (22 patients) received 1.0 g intravenous TXA 30 min before surgery and 1.0 g at intervals of 3, 6, and 9 h before surgery. The 1-dose TXA group (25 patients) received 1.0 g intravenous TXA 30 min before surgery, while the control group (32 patients) did not receive TXA. LMWH was applied 12 h after surgery in each group. The primary metrics evaluated included hidden blood loss (HBL), total blood loss (TBL), and the number and incidence rate of deep vein thrombosis (DVT). RESULTS Analysis of the HBL revealed that the 4-dose TXA group had the lowest average (583.13±318.08 ml), followed by the 1-dose TXA group (902.94±509.99 ml), and the control group showed the highest (1154.39±452.06 ml) (P<0.05). A similar result was observed for TBL (4-dose group: 640.86±337.22 ml, 1-dose group: 971.74±511.14 ml, control group: 1226.27±458.22 ml, P<0.05). Regarding DVT, the 4-dose TXA group had 5 cases (incidence rate 22.73%), the 1-dose TXA group had 6 cases (incidence rate 24.00%), and the control group had 8 cases (incidence rate 25.00%), with no significant difference among groups (P>0.05). CONCLUSIONS Treatment using 4-dose TXA and LMWH can effectively reduce PBL without increasing the DVT risk in IF patients with IMN.


Assuntos
Perda Sanguínea Cirúrgica , Heparina de Baixo Peso Molecular , Fraturas do Quadril , Ácido Tranexâmico , Trombose Venosa , Humanos , Ácido Tranexâmico/administração & dosagem , Ácido Tranexâmico/uso terapêutico , Feminino , Masculino , Fraturas do Quadril/cirurgia , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/uso terapêutico , Idoso , Perda Sanguínea Cirúrgica/prevenção & controle , Trombose Venosa/tratamento farmacológico , Trombose Venosa/prevenção & controle , Estudos Prospectivos , Pessoa de Meia-Idade , Assistência Perioperatória/métodos , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/uso terapêutico , Idoso de 80 Anos ou mais , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/efeitos adversos
3.
J Clin Ultrasound ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041232

RESUMO

Sarcoid myositis is a rare and often debilitating extrapulmonary manifestation of sarcoidosis that can be difficult to recognize without a prior sarcoidosis diagnosis. Sarcoidosis with muscle nodules or masses as the first symptom is the least common form, occurring in approximately 0.5%-2.3% of cases. This article presents four middle-aged female patients who initially sought medical attention for a lower limb mass. Ultrasound examinations revealed consistent characteristic changes indicative of myositis. All patients underwent ultrasound-guided muscle biopsy and were diagnosed with sarcoidosis. Therefore, ultrasonography plays a pivotal role as the primary diagnostic tool for the early detection of sarcoid myositis.

4.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38803280

RESUMO

OBJECTIVES: To explore the diagnostic value of ultrasonography for injuries of anterior talofibular ligament (ATFL) and anterior inferior tibiofibular ligament distal fascicle (ATiFL-DF) in patients with ankle fractures. METHODS: Clinical data of 51 patients with ankle fractures who were clinically suspected of ligament injuries and underwent ankle ultrasonography examination and arthroscopy in Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from April 2019 to March 2023 were retrospectively analyzed. Using arthroscopic findings as the gold standard, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ultrasonography in diagnosing ATFL and ATiFL-DF injuries were evaluated; and Kappa consistency test was further performed. RESULTS: The sensitivity and specificity of ultrasonography in diagnosis of ATFL injury were 100.0% and 92.3%, with the PPV of 92.6% and NPV of 100.0%. Ultrasonography findings exhibited excellent concordance with arthroscopic results (kappa=0.849). The sensitivity and specificity of ultrasonography in diagnosis of ATiFL-DF injury was 86.7% and 33.3%, with the PPV of 90.7% and NPV of 25.0%. But the consistence between ultrasonography and arthroscopic results was poor (kappa=0.168). CONCLUSIONS: Ultrasonography is a reliable diagnostic modality for assessing injuries to the ATFL in patients with ankle fractures; however, its specificity is limited when evaluating injuries to the ATiFL-DF. Therefore, ankle arthroscopy is necessary for ankle fracture patients with negative findings of ATiFL-DF in ultrasonography.

5.
Int J Biol Macromol ; 268(Pt 2): 131625, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38631569

RESUMO

Nano zero-valent iron (nZVI) is an advanced environmental functional material for the degradation of tetrabromobisphenol A (TBBPA). However, high surface energy, self-agglomeration and low electron selectivity limit degradation rate and complete debromination of bare nZVI. Herein, we presented biomass-derived cellulose nanocrystals (CNC) modified nZVI (CNC/nZVI) for enhanced TBBPA removal. The effects of raw material (straw, filter paper and cotton), process (time, type and concentration of acid hydrolysis) and synthesis methods (in-situ and ex-situ) on fabrication of CNC/nZVI were systematically evaluated based on TBBPA removal performance. The optimized CNC-S/nZVI(in) was prepared via in-situ liquid-phase reduction using straw as raw material of CNC and processing through 44 % H2SO4 for 165 min. Characterizations illustrated nZVI was anchored to the active sites at CNC interface through electrostatic interactions, hydrogen bonds and FeO coordinations. The batch experiments showed 0.5 g/L CNC-S/nZVI(in) achieved 96.5 % removal efficiency at pH = 7 for 10 mg/L initial TBBPA. The enhanced TBBPA dehalogenation by CNC-S/nZVI(in), involving in initial adsorption, reduction process and partial detachment of debrominated products, were possibly attributed to elevated pre-adsorption capacity and high-efficiency delivery of electrons synergistically. This study indicated that fine-tuned fabrication of CNC/nZVI could potentially be a promising alternative for remediation of TBBPA-contaminated aquatic environments.


Assuntos
Biomassa , Celulose , Ferro , Nanopartículas , Bifenil Polibromatos , Bifenil Polibromatos/química , Celulose/química , Nanopartículas/química , Ferro/química , Poluentes Químicos da Água/química , Adsorção
6.
Nat Commun ; 15(1): 2110, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454003

RESUMO

Pilot-diesel-ignition ammonia combustion engines have attracted widespread attentions from the maritime sector, but there are still bottleneck problems such as high unburned NH3 and N2O emissions as well as low thermal efficiency that need to be solved before further applications. In this study, a concept termed as in-cylinder reforming gas recirculation is initiated to simultaneously improve the thermal efficiency and reduce the unburned NH3, NOx, N2O and greenhouse gas emissions of pilot-diesel-ignition ammonia combustion engine. For this concept, one cylinder of the multi-cylinder engine operates rich of stoichiometric and the excess ammonia in the cylinder is partially decomposed into hydrogen, then the exhaust of this dedicated reforming cylinder is recirculated into the other cylinders and therefore the advantages of hydrogen-enriched combustion and exhaust gas recirculation can be combined. The results show that at 3% diesel energetic ratio and 1000 rpm, the engine can increase the indicated thermal efficiency by 15.8% and reduce the unburned NH3 by 89.3%, N2O by 91.2% compared to the base/traditional ammonia engine without the proposed method. At the same time, it is able to reduce carbon footprint by 97.0% and greenhouse gases by 94.0% compared to the traditional pure diesel mode.

7.
J Ethnopharmacol ; 325: 117812, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38301984

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Diabetic ulcers represent a chronic condition characterized by prolonged hyperglycemia and delayed wound healing, accompanied by endocrine disorders, inflammatory responses, and microvascular damage in the epidermal tissue, demanding effective clinical treatment approaches. For thousands of years, ancient Chinese ethnopharmacological studies have documented the use of Poria cocos (Schw.) Wolf in treating diabetic ulcers. Recent research has substantiated the diverse pharmacological effects of Poria cocos (Schw.) Wolf, including its potential to alleviate hyperglycemia and exhibit anti-inflammatory, antioxidant, and immune regulatory properties, which could effectively mitigate diabetic ulcer symptoms. Furthermore, being a natural medicine, Poria cocos (Schw.) Wolf has demonstrated promising therapeutic effects and safety in the management of diabetic ulcers, holding significant clinical value. Despite its potential clinical efficacy and applications in diabetic ulcer treatment, the primary active components and underlying pharmacological mechanisms of Poria cocos (Schw.) Wolf remains unclear. Further investigations are imperative to establish a solid foundation for drug development in this domain. AIM OF THE STUDY AND MATERIALS AND METHODS: In this study, we aimed to identify the active compounds and potential targets of Poria cocos (Schw.) Wolf using UHPLC-Q-TOF-MS and TCMSP databases. Additionally, we attempt to identify targets related to diabetic ulcers. Following enrichment analysis, a network of protein-protein interactions was constructed to identify hub genes based on the common elements between the two datasets. To gain insights into the binding activities of the hub genes and active ingredients, molecular docking analysis was employed. Furthermore, to further validate the therapeutic effect of Poria cocos (Schw.) Wolf, we exerted in vitro experiments using human umbilical vein vascular endothelial cells and human myeloid leukemia monocytes (THP-1). The active ingredient of Poria cocos (Schw.) Wolf was applied in these experiments. Our investigations included various assays, such as CCK-8, scratch test, immunofluorescence, western blotting, RT-PCR, and flow cytometry, to explore the potential of Poria cocos (Schw.) Wolf triterpenoid extract (PTE) in treating diabetic ulcers. RESULTS: The findings here highlighted PTE as the primary active ingredient in Poria cocos (Schw.) Wolf. Utilizing network pharmacology, we identified 74 potential targets associated with diabetic ulcer treatment for Poria cocos (Schw.) Wolf, with five hub genes (JUN, MAPK1, STAT3, AKT1, and CTNNB1). Enrichment analysis revealed the involvement of multiple pathways in the therapeutic process, with the PI3K-AKT signaling pathway showing significant enrichment. Through molecular docking, we discovered that relevant targets within this pathway exhibited strong binding with the active components of Poria cocos (Schw.) Wolf. In vitro experiments unveiled that PTE (10 mg/L) facilitated the migration of human umbilical vein vascular endothelial cells (P < 0.05). PTE also increased the expression of CD31 and VEGF mRNA (P < 0.05) while activating the expressions of p-PI3K and p-AKT (P < 0.05). Moreover, PTE demonstrated its potential by reducing the expression of IL-1ß, IL-6, TNF-α, and NF-κB mRNA in THP-1 (P < 0.05) and fostering M2 macrophage polarization. These results signify the potential therapeutic effects of PTE in treating diabetic ulcers, with its beneficial actions mediated through the PI3K-AKT signaling pathway. CONCLUSIONS: PTE is the main active ingredient in Poria cocos (Schw.) Wolf that exerts therapeutic effects. Through PI3K-AKT signaling pathway activation and inflammatory response reduction, PTE promotes angiogenesis, thereby healing diabetic ulcers.


Assuntos
Antineoplásicos , Diabetes Mellitus , Medicamentos de Ervas Chinesas , Hiperglicemia , Triterpenos , Wolfiporia , Lobos , Animais , Humanos , Proteínas Proto-Oncogênicas c-akt , Wolfiporia/química , Fosfatidilinositol 3-Quinases , Úlcera , Simulação de Acoplamento Molecular , Células Endoteliais , Transdução de Sinais , Antineoplásicos/farmacologia , Triterpenos/farmacologia , Triterpenos/uso terapêutico , Triterpenos/análise , RNA Mensageiro , Diabetes Mellitus/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico
8.
Acad Radiol ; 31(7): 2838-2847, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38233258

RESUMO

RATIONALE AND OBJECTIVES: To investigate the predictors of Gleason Grading Group (GGG) upgrading in low-risk prostate cancer (Gleason score=3 + 3) from transperineal biopsy after radical prostatectomy (RP). MATERIALS AND METHODS: The clinical data of 160 patients who underwent transperineal biopsy and RP from January 2017 to December 2022 were retrospectively analyzed. First, univariate and multivariate logistic regression analysis were used to obtain independent predictors of postoperative GGG upgrading. Then receiver operating characteristic curve was used to evaluate the diagnostic efficacy of predictors. Finally, Linear-by-Linear Association test was used to analyze the risk trends of patients in different predictor groups in the postoperative GGG. RESULTS: In this study, there were 81 cases (50.6%) in the GGG concordance group and 79 cases (49.4%) in the GGG upgrading group. Univariate analysis showed age, free/total prostate-specific antigen (f/tPSA), proportion of positive biopsies, positive target of magnetic-resonance imaging (MRI) and positive target of contrast-enhanced ultrasound had significant effects on GGG upgrading (all P < .05). In multivariate logistic regression analysis, age (odds ratio [OR]=1.066, 95%CI=1.007-1.127, P = .027), f/tPSA (OR=0.001, 95%CI=0-0.146, P = .001) and positive target of MRI (OR=3.005, 95%CI=1.353-76.674, P = .007) were independent predictors. The prediction model (area under curve=0.751 P < .001) had higher predictive efficacy than all independent predictors. The proportion of patients in exposed group of different GGG increased with the level of GGG, but decreased in nonexposed group, and the linear trend was significantly different (all P < .001). CONCLUSION: Age, f/tPSA, and positive target of MRI were independent predictors of postoperative GGG upgrading. The predictive model constructed had the best diagnostic efficacy.


Assuntos
Gradação de Tumores , Prostatectomia , Neoplasias da Próstata , Humanos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Imageamento por Ressonância Magnética/métodos , Biópsia , Biópsia Guiada por Imagem/métodos , Próstata/patologia , Próstata/diagnóstico por imagem
9.
Artigo em Inglês | MEDLINE | ID: mdl-38330520

RESUMO

Paralytic shellfish poisoning (PSP) is the most widespread and harmful form of shellfish poisoning with high mortality rate. In this study, a combined desorption electrospray ionization mass spectrometry (DESI-MS) and ultra-performance liquid chromatography triple quadrupole mass spectrometry (UPLC-QqQ/MS) method was established for the detection of PSPs in urine. The method was optimized using a spray solution of methanol and water (1:1, v/v) containing 0.1 % FA, at a flow rate of 2.5 µL·min-1 and an applied voltage of 3 kV. The limit of detection (LOD) for PSPs detection by DESI-MS was in the range of 87-265 µg·L-1, which basically meets the requirements for the rapid screening of PSPs. The LOD for UPLC-QqQ/MS was in the range of 2.2-14.9 µg·L-1, with a limit of quantification (LOQ) of 7.3-49.7 µg·L-1, thus fulfilling the quantitative demand for PSPs in urine. Finally, after spiking the urine samples of six volunteers with PSPs to a concentration of 100 µg·L-1, DESI-MS successfully and efficiently detected the positive samples. Subsequently, UPLC-QqQ/MS was employed for precise quantification, yielding results in the range of 84.6-95.1 µg·L-1. The experimental findings demonstrated that the combination of DESI-MS and UPLC-QqQ/MS enables high-throughput, rapid screening of samples and accurate quantification of positive samples, providing assurance for food safety and human health.


Assuntos
Intoxicação por Frutos do Mar , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Intoxicação por Frutos do Mar/diagnóstico , Espectrometria de Massas em Tandem/métodos , Espectrometria de Massa com Cromatografia Líquida , Limite de Detecção
10.
J Chromatogr A ; 1718: 464715, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38330726

RESUMO

G protein-coupled receptors (GPCRs) are one of the most prominent targets for drug discovery. Immobilizing GPCRs has proven to be an effective strategy for expanding the utility of GPCRs into nonbiological contexts. However, traditional strategies of immobilizing GPCRs have been severely challenged due to the loss of receptor function. Here, we reported a novel and general approach to realize the label-free and site-selective immobilization of 5-hydroxytryptamine 1A receptor (5-HT1AR) and the application in developing a chromatographic method with improved specificity for pursuing 5-HT1AR ligands from natural products. This method involved the use of a clickable non-natural amino acid, O-allyl-L-tyrosine (O-ALTyr) to immobilize the receptor onto thiol-functionalized silica gels through a 'thiol-ene' click chemistry, which allowed us to avoid the purification step and directly immobilize 5-HT1AR on silica gels. The immobilized receptor was characterized using immunofluorescence assay, and receptor-ligand interaction analysis was conducted through frontal analysis. To test the feasibility of the immobilized 5-HT1ARO-ALTyr in complex matrices, bioactive compounds in Ziziphi Spinosae Semen (ZSS) were screened and their interaction with the receptor was assessed using zonal elution. Our findings indicated that immobilizing the receptor through nnAAs effectively minimizes the chromatographic peak tailing and broadening of specific ligands, leading to a significant improvement in chromatographic performance. The association constants of the three ligands to 5-HT1AR were approximately one order of magnitude greater than those of Halo-tag attachment. These results demonstrated that the immobilized 5-HT1AR exhibits high specificity and the ability to recognize receptor ligands from complex matrices. This allowed us to identify magnoflorine (Mag) as a potential ligand of 5-HT1AR from ZSS extract. In vivo assay also proved that Mag presented a promising anxiolytic effect by promoting the expression of 5-HT1AR in mice brain. The above findings pointed to the fact that the immobilized 5-HT1AR affinity chromatographic strategy relying on the site-specific encoded non-natural amino acid is a powerful alternative for precisely determining the drug-protein interaction and discovering the specific ligand of GPCRs from complex matrixes.


Assuntos
Aminoácidos , Receptor 5-HT1A de Serotonina , Camundongos , Animais , Ligantes , Serotonina , Receptores Acoplados a Proteínas G , Cromatografia de Afinidade/métodos , Tirosina , Compostos de Sulfidrila , Dióxido de Silício , Géis
11.
Cell Discov ; 10(1): 20, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378648

RESUMO

Adenine base editors (ABEs) and cytosine base editors (CBEs) enable the single nucleotide editing of targeted DNA sites avoiding generation of double strand breaks, however, the genomic features that influence the outcomes of base editing in vivo still remain to be characterized. High-throughput datasets from lentiviral integrated libraries were used to investigate the sequence features affecting base editing outcomes, but the effects of endogenous factors beyond the DNA sequences are still largely unknown. Here the base editing outcomes of ABE and CBE were evaluated in mammalian cells for 5012 endogenous genomic sites and 11,868 genome-integrated target sequences, with 4654 genomic sites sharing the same target sequences. The comparative analyses revealed that the editing outcomes of ABE and CBE at endogenous sites were substantially different from those obtained using genome-integrated sequences. We found that the base editing efficiency at endogenous target sites of both ABE and CBE was influenced by endogenous factors, including epigenetic modifications and transcriptional activity. A deep-learning algorithm referred as BE_Endo, was developed based on the endogenous factors and sequence information from our genomic datasets, and it yielded unprecedented accuracy in predicting the base editing outcomes. These findings along with the developed computational algorithms may facilitate future application of BEs for scientific research and clinical gene therapy.

12.
Nat Commun ; 15(1): 1467, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368411

RESUMO

The noncentrosymmetric ferromagnetic Weyl semimetal CeAlSi with simultaneous space-inversion and time-reversal symmetry breaking provides a unique platform for exploring novel topological states. Here, by employing multiple experimental techniques, we demonstrate that ferromagnetism and pressure can serve as efficient parameters to tune the positions of Weyl nodes in CeAlSi. At ambient pressure, a magnetism-facilitated anomalous Hall/Nernst effect (AHE/ANE) is uncovered. Angle-resolved photoemission spectroscopy (ARPES) measurements demonstrated that the Weyl nodes with opposite chirality are moving away from each other upon entering the ferromagnetic phase. Under pressure, by tracing the pressure evolution of AHE and band structure, we demonstrate that pressure could also serve as a pivotal knob to tune the positions of Weyl nodes. Moreover, multiple pressure-induced phase transitions are also revealed. These findings indicate that CeAlSi provides a unique and tunable platform for exploring exotic topological physics and electron correlations, as well as catering to potential applications, such as spintronics.

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