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1.
Cancer Biol Med ; 20(1)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36647779

RESUMO

Mechanical forces in the tumor microenvironment (TME) are associated with tumor growth, proliferation, and drug resistance. Strong mechanical forces in tumors alter the metabolism and behavior of cancer cells, thus promoting tumor progression and metastasis. Mechanical signals are transformed into biochemical signals, which activate tumorigenic signaling pathways through mechanical transduction. Cancer immunotherapy has recently made exciting progress, ushering in a new era of "chemo-free" treatments. However, immunotherapy has not achieved satisfactory results in a variety of tumors, because of the complex tumor microenvironment. Herein, we discuss the effects of mechanical forces on the tumor immune microenvironment and highlight emerging therapeutic strategies for targeting mechanical forces in immunotherapy.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/patologia , Carcinogênese , Imunoterapia/métodos
2.
Phys Rev Lett ; 130(1): 016301, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36669212

RESUMO

Berry curvature dipole plays an important role in various nonlinear quantum phenomena. However, the maximum symmetry allowed for nonzero Berry curvature dipole in the transport plane is a single mirror line, which strongly limits its effects in materials. Here, via probing the nonlinear Hall effect, we demonstrate the generation of Berry curvature dipole by applied dc electric field in WTe_{2}, which is used to break the symmetry constraint. A linear dependence between the dipole moment of Berry curvature and the dc electric field is observed. The polarization direction of the Berry curvature is controlled by the relative orientation of the electric field and crystal axis, which can be further reversed by changing the polarity of the dc field. Our Letter provides a route to generate and control Berry curvature dipole in broad material systems and to facilitate the development of nonlinear quantum devices.


Assuntos
Eletricidade , Frutas
3.
Materials (Basel) ; 16(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36676233

RESUMO

Temperature control is needed in the construction process of massive concrete and it can avoid the concrete cracks. Prediction of temperature development based on a hydration kinetics model can reduce the need for adiabatic temperature rise tests for concrete. However, the existing hydration kinetics model cannot accurately describe the hydration process of cement, thereby limiting the ability to further accurately predict the temperature rise of concrete based on the hydration kinetics model. This paper aims to establish a new hydration kinetics model, which is based on nucleation and growth model, and to predict the temperature development of concrete with set-controlling admixture based on this model. In this paper, the nucleation and growth of hydration products and the diffusion of free water by the modified boundary of nucleation and growth (BNG) model and the modified Fuji and Kondo's model are described. The relationship between nucleation rate and apparent activation energy and the relationship between effective diffusion coefficient and apparent activation energy are linear. However, the relationship between growth rate and apparent activation is exponential. Finally, the temperature development of concrete can be calculated by the hydration degree of the cement.

4.
Mol Neurobiol ; 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689134

RESUMO

Opioids are often first-line analgesics in pain therapy. However, prolonged use of opioids causes paradoxical pain, termed "opioid-induced hyperalgesia (OIH)." The infralimbic medial prefrontal cortex (IL-mPFC) has been suggested to be critical in inflammatory and neuropathic pain processing through its dynamic output from layer V pyramidal neurons. Whether OIH condition induces excitability changes of these output neurons and what mechanisms underlie these changes remains elusive. Here, with combination of patch-clamp recording, immunohistochemistry, as well as optogenetics, we revealed that IL-mPFC layer V pyramidal neurons exhibited hyperexcitability together with higher input resistance. In line with this, optogenetic and chemogenetic activation of these neurons aggravates behavioral hyperalgesia in male OIH rats. Inhibition of these neurons alleviates hyperalgesia in male OIH rats but exerts an opposite effect in male control rats. Electrophysiological analysis of hyperpolarization-activated cation current (Ih) demonstrated that decreased Ih is a prerequisite for the hyperexcitability of IL-mPFC output neurons. This decreased Ih was accompanied by a decrease in HCN1, but not HCN2, immunolabeling, in these neurons. In contrast, the application of HCN channel blocker increased the hyperalgesia threshold of male OIH rats. Consequently, we identified an HCN-channel-dependent hyperexcitability of IL-mPFC output neurons, which governs the development and maintenance of OIH in male rats.

5.
Biotechnol Genet Eng Rev ; : 1-11, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36606759

RESUMO

OBJECTIVE: To investigate the correlation between methylenetetrahydrofolate reductase (MTHFR) gene-specific methylation and recurrent spontaneous abortion (RSA). METHODS: A total of 50 RSA patients who visited our hospital were recruited in the study group; 50 multiparous women who underwent physical examinations during the same period were enrolled in the control group. The levels of homocysteine, folic acid, and vitamin B12 and their MTHFR gene polymorphism and specific methylation were measured in both groups. The Logistic regression equation was used to analyze the correlation between MTHFR gene-specific methylation and RSA. RESULTS: The methylated allele MM was not found in the control group, and the frequency in the study group was 1.19%. The frequency of the MU genotype in the study group 32.93% was higher than that in the control group 12.45%. The frequency of methylated alleles of CC and CT genotypes carrying MTHFR C677T polymorphism in the study group was higher than that in the control group (P < 0.05). There was no significant difference in the TT genotype between the two groups (P > 0.05). Multivariate Logistic regression analysis exhibited that patients with methylated alleles of CC genotype had a risk of RSA increased by 1.167 times, and the risk increased by 2.500 times in patients with methylated alleles of CT genotype (P < 0.05). 83.33% of RSA patients carrying methylated alleles affected hyperhomocysteinemia. In patients with elevated homocysteine levels, the risk of RSA caused by methylated allele was significantly increased by 7.321 times. CONCLUSION: MTHFR gene-specific methylation can significantly increase the risk of RSA.

6.
Vaccines (Basel) ; 10(12)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36560428

RESUMO

OBJECTIVES: The current study aims to survey the willingness of parents to vaccinate their children, who are childhood acute lymphoblastic leukemia survivors (CALLS), and identify factors associated with vaccine acceptance. METHODS: Parents of CALLS on/off treatment, with the general condition of being amendable to vaccination, were recruited for interviews with attending oncologists about COVID-19 vaccination acceptance from July to November 2021 in China. After controlling for socioeconomic factors, the Association of Oncologists' recommendations and parent-oncologist alliance with acceptance status were investigated. For validation, propensity score-matched (PSM) analysis was used. RESULTS: A total of 424 families were included in the study, with CALLS mean remission age of 5.99 ± 3.40 years. Among them, 91 (21.4%) agreed, 168 (39.6%) hesitated, and 165 (38.9%) parents disagreed with the vaccination. The most common reason that kept parents from vaccinating their children was lack of recommendations from professional personnel (84/165, 50.9%), and massive amounts of internet information (78/175, 44.6%) was the main nonhealthcare resource against vaccination. Logistic regression analysis showed that only the recommendation from the oncologist was associated with parents' vaccine acceptance (OR = 3.17, 95% CI = 1.93-5.20), as demonstrated by PSM comparison (42 in recommendation group vs. 18 in nonrecommendation group among 114 pairs, p < 0.001). An exploratory analysis revealed that parents with a better patient-oncologist alliance had a significantly higher level of acceptance (65.6% in alliance group vs. 15.6% in nonalliance group among 32 pairs, p < 0.001). CONCLUSIONS: Due to a lack of professional recommendation resources and the potential for serious consequences, parents were generally reluctant to vaccinate their CALLS. The recommendation of oncologists, which was influenced by the parent-oncologist alliance, significantly increased acceptance. This study emphasizes the critical role of oncologists in vaccinating cancer survivors and can be used to promote COVID-19 vaccines among vulnerable populations.

7.
Lab Chip ; 23(1): 125-135, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36477690

RESUMO

Real-time image-based sorting of target cells in a precisely indexed manner is desirable for sequencing or cultivating individual human or microbial cells directly from clinical or environmental samples; however, the versatility of existing methods is limited as they are usually not broadly applicable to all cell sizes. Here, an optical tweezer-assisted pool-screening and single-cell isolation (OPSI) system is established for precise, indexed isolation of individual bacterial, yeast or human-cancer cells. A controllable static flow field that acts as a cell pool is achieved in a microfluidics chip, to enable precise and ready screening of cells of 1 to 40 µm in size by bright-field, fluorescence, or Raman imaging. The target cell is then captured by a 1064 nm optical tweezer and deposited as one-cell-harboring nanoliter microdroplets in a one-cell-one-tube manner. For bacterial, yeast and human cells, OPSI achieves a >99.7% target-cell sorting purity and a 10-fold elevated speed of 10-20 cells per min. Moreover, OPSI-based one-cell RNA-seq of human cancer cells yields high quality and reproducible single-cell transcriptome profiles. The versatility, facileness, flexibility, modularized design, and low cost of OPSI suggest its broad applications for image-based sorting of target cells.


Assuntos
Pinças Ópticas , Saccharomyces cerevisiae , Humanos , Separação Celular/métodos , Microfluídica/métodos , Transcriptoma
8.
Biomed Pharmacother ; 156: 113959, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36411663

RESUMO

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) bring significant benefits to non-small cell lung cancer patients with EGFR mutations, which represent a breakthrough in lung cancer therapy. However, patients will ultimately develop the acquired resistance to the first- or second-generation EGFR-TKIs after a period of treatment, and EGFR T790M mutation is the most common resistant mechanism. The third-generation EGFR-TKIs target T790M mutation and show potent anti-tumor efficacy, especially in central neural system response. Unfortunately, patients inevitably get resistant to the third-generation EGFR-TKIs due to various mechanisms, which can be mainly divided into EGFR-dependent and -independent ones. EGFR-dependent mechanism refers to manifold EGFR mutations while EGFR-independent mechanisms include bypass signal activation, histologic transformation and so on. To precisely address this issue and improve clinical outcomes, various other therapies (e.g. chemotherapy, radiotherapy, etc.) in combination with the third-generation EGFR-TKIs are designed. However, the current results of combination therapies are insufficient and ambiguous, which remain further exploration. Herein, we provide an updated landscape of the third-generation EGFR-TKIs and elaborate on the complex resistant mechanisms. Notably, we summarize the combination therapies with third-generation EGFR-TKIs and discuss their limitations and future perspective, aiming at providing insights to clinicians from bench to bedside.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Mutação , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
9.
Dalton Trans ; 51(47): 17994-18009, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36367710

RESUMO

A Bi2WO6/BiOBr/RGO (BWO/BOB/RGO) composite photocatalyst with a Z-type heterojunction was prepared by a simple one-pot hydrothermal method, and the micro-morphology and physicochemical properties of the prepared samples were characterized. After reacting under visible light for 120 min, the degradation rate of 20 mg L-1 norfloxacin (NOR) by BWO/BOB/RGO was 95.12%, and the kinetic constant of the reaction was 6.42 times higher than that of pure BiOBr. Furthermore, BWO/BOB/RGO also shows good recycling stability and universality. The characterization results show that the improvement of the photocatalytic performance of the catalyst is mainly due to the heterojunction formed between Bi2WO6, RGO and BiOBr, which enhances the visible light absorption ability, accelerates the photogenerated electron migration and improves the electron-hole pair separation efficiency. The introduction of Bi2WO6 and RGO into the catalyst also increased its specific surface area and made it have more surface-active sites. The results of radical capture experiments showed that ˙O2- and h+ played an important role in the BWO/BOB/RGO reaction system, and the intermediate products and possible degradation pathways of the system were detected and analyzed. Furthermore, the electron transfer mechanism of the Z-type heterojunction using RGO as an electron transport medium and the mechanism of photocatalytic degradation of norfloxacin were proposed.

10.
Appl Opt ; 61(21): 6134-6143, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-36256225

RESUMO

A lock-in thermography technique based on a periodical square wave is used to detect stainless steel plates with defects. Combining a neural network with lock-in thermography, an image processing technique is proposed, and the results are compared with traditional image processing methods. A full-field defect reconstruction technology is proposed that combines pulsed phase thermography, threshold segmentation technology, and lock-in thermography technology to reconstruct the full-field depth image. This method has fast processing speed and high detection accuracy. Finally, the effects of excitation frequency and duty cycle on thermal image quality, defect detection range, and defect detection accuracy are investigated through extensive experiments to arrive at the optimal excitation frequency and duty cycle.

11.
World Neurosurg ; 2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36283650

RESUMO

BACKGROUND: The needle puncture model in rats has been accepted as an ordinary model to induce intervertebral disc degeneration (IVDD). However, the model primarily penetrated the whole intervertebral disc, resulting in injury to the nucleus pulposus (NP) and annulus fibrosus (AF). The intention of this research was to explore a minimally invasive approach through needle puncture of the AF percutaneously in rats. METHODS: Twenty SD rats underwent puncture at Co8/9 via a 20 G percutaneous needle. The needle was slowly advanced perpendicular to the tail skin to penetrate the whole AF without damaging the NP limited by a hand-made sheath. The X-rays and magnetic resonance imaging T2 relaxation was evaluated at 1, 2, and 3 weeks to assess the disc height index and signal changes. Histological and immunohistochemical staining of the IVD were obtained under a light microscope. RESULTS: X-rays showed that the disc height had progressively narrowed to 49% of baseline 3 weeks after injury. magnetic resonance imaging evaluation demonstrated that the mean T2-weighted signal intensity at 3 weeks was 43% of that in the uninjured control group at the Co8/9 level. Histological staining demonstrated disorganized lamellae in the AF and decreased proteoglycan content and cellularity within the NP in the injured discs. CONCLUSIONS: The present research demonstrates a reliable and convenient approach to induce an AF tear in rats through percutaneous needle puncture. This model reduces harm to the experimental animals significantly while imitating the progressive degeneration process. More importantly, the model confirmed that AF damage alone could lead to IVDD and provided a research method for AF degeneration in IVDD.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36227811

RESUMO

Recently, template-based trackers have become the leading tracking algorithms with promising performance in terms of efficiency and accuracy. However, the correlation operation between query feature and the given template only achieves accurate target localization, but is prone to state estimation error, especially when the target suffers from severe deformation. To address this issue, segmentation-based trackers are proposed that use per-pixel matching to improve the tracking performance of deformable objects effectively. However, most of the existing trackers only match with the target features of the initial frame, thereby lacking the discrimination for handling a variety of challenging factors, e.g., similar distractors, background clutter, and appearance change. To this end, we propose a dynamic compact memory embedding technique to enhance the discrimination of the segmentation-based visual tracking method that can well tell the target from the background. Specifically, we initialize a memory embedding with the target features in the first frame. During the tracking process, the current target features that have certain correlation with the existing memory are updated to the memory embedding online. To further improve the tracking accuracy for deformable objects, we use a weighted point-to-global matching strategy to measure the correlation between the pixelwise query feature and the whole template, so as to capture more detailed deformation information. Extensive evaluations on six challenging tracking benchmarks including VOT2016, VOT2018, VOT2019, GOT-10K, TrackingNet, and LaSOT demonstrate the superiority of our method over recent remarkable trackers. Besides, our tracker outperforms the excellent segmentation-based trackers, i.e., D3S and SiamMask on the DAVIS2017 benchmark. The code is available at https://github.com/peace-love243/CMEDFL.

13.
Materials (Basel) ; 15(20)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36295318

RESUMO

To investigate the relationship between the dislocation configuration and the grain refinement in the NV E690 cladding layer caused by laser shock peening, NV E690 high-strength steel powder was used to repair prefabricated pits in samples of 690 high-strength steel by laser cladding, where the laser shock peening of the cladding layer was performed by laser shock at different power densities. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were used to observe the microstructures of these samples before and after the laser shock process. The results showed that the metallurgical bonding between the cladding layer and the substrate after laser cladding repair was good. When the laser power density was 4.77 GW/cm2, multiple edge dislocations, dislocation dipoles, and extended dislocations were distributed over the cladding layer. When the laser power density was 7.96 GW/cm2, a geometrically necessary dislocation divided the large original grain into two subgrains with different orientations. When the laser power density was 11.15 GW/cm2, geometric dislocations divided the entire large grain into fine grains. The grain refinement model of the NV E690 cladding layer, when treated by laser shock peening, can describe the grain refinement process induced by the dislocation movement of this cladding layer.

14.
Physica A ; 607: 128217, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36187304

RESUMO

In the current paper, we investigate the problem of how do crude oil futures hedge crude oil spot risk after the COVID-19 outbreak. Specifically, given that noise, conditional higher moments and asymmetric tail dependence may exist in crude oil markets, a Wavelet denoising-GARCHSK-SJC Copula hedge ratio estimation method is proposed to construct hedging portfolios in crude oil markets during the epidemic period. Based on the in-sample and out-of-sample results, the hedging roles of Brent futures and Shanghai crude oil (SC) futures for light and medium crude spots after the COVID-19 outbreak are further researched. The empirical results demonstrate that noise, conditional higher moments and asymmetric tail dependence do exist in crude futures and spots, which have impact on the precision of modeling results. Secondly, the Wavelet denoising-GARCHSK-SJC Copula hedge ratio estimation method outperforms all control groups, obtaining the best in-sample and out-of-sample hedging effectiveness. Finally, it is reported in the in-sample and out-of-sample hedging results that Brent is the optimal futures to hedge light oil, while SC is the optimal futures to hedge medium oil. The paper provides substantial recommendations for policymakers and investors.

15.
Anal Methods ; 14(40): 3944-3952, 2022 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-36222117

RESUMO

Heavy metal concentration is an important index for evaluating soil pollution. It is of great significance to measure the trace element content accurately for green agriculture development. In order to detect the trace element content accurately, a new prediction framework including pre-processing, signal extraction, feature selection and decision-making was proposed. The energy dispersive X-ray fluorescence (ED-XRF) spectra of 57 national standard soil samples were investigated based on the proposed methods. Firstly, an innovative background deduction method called iterative adaptive window empirical wavelet transform (IAWEWT) was introduced to extract effective counts of characteristic peaks, and the proposed approach was validated by the coefficient of determination (R2) of the instrumental calibration curve compared with two other conventional methods. Secondly, principal component analysis (PCA) was combined with the analysis of variance (ANOVA) for variable selection optimization of the ED-XRF spectrum. After PCA feature extraction and ANOVA variable selection treatment, the optimum number of principal components for V, Cr, Cu, Zn, Mo, Cd and Pb were determined to be 7, 15, 4, 4, 4, 5 and 12 respectively. Furthermore, the support vector regression (SVR) model was adopted for heavy metal estimation. The evaluation indices included R2 and root mean square error (RMSE). It was demonstrated that the predictive capabilities of seven heavy metal elements were improved substantially for elemental analysis by the proposed PCA-ANOVA-SVR model, with excellent results for V, Cr, Cu, Zn, Mo, Cd and Pb estimates, and the R2 values were 0.993, 0.996, 0.999, 0.999, 0.997, 0.998 and 0.998 respectively. Therefore, the new framework proposed in this paper can effectively eliminate redundant features and determine the concentration of trace elements in soil. It provides an effective alternative for the quantitative analysis of X-ray fluorescence spectrometry.


Assuntos
Metais Pesados , Poluentes do Solo , Oligoelementos , Solo/química , Oligoelementos/análise , Poluentes do Solo/análise , Análise de Componente Principal , Raios X , Cádmio/análise , Chumbo/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Análise de Variância
16.
Front Endocrinol (Lausanne) ; 13: 980867, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093072

RESUMO

Primary osteoporosis has long been underdiagnosed and undertreated. Currently, ferroptosis may be a promising research direction in the prevention and treatment of primary osteoporosis. However, the specific mechanism of ferroptosis in primary osteoporosis remains a mystery. Differentially expressed genes (DEGs) were identified in bone mesenchymal stromal cells (BMSCs) of primary osteoporosis and heathy patients from the GEO databases with the help of bioinformatics analysis. Then, we intersected these DEGs with the ferroptosis dataset and obtained 80 Ferr-DEGs. Several bioinformatics algorithms (PCA, RLE, Limma, BC, MCC, etc.) were adopted to integrate the results. Additionally, we explored the potential functional roles of the Ferr-DEGs via GO and KEGG. Protein-protein interactions (PPI) were used to predict potential interactive networks. Finally, 80 Ferr-DEGs and 5 key Ferr-DEGs were calculated. The 5 key Ferr-DEGs were further verified in the OVX mouse model. In conclusion, through a variety of bioinformatics methods, our research successfully identified 5 key Ferr-DEGs associated with primary osteoporosis and ferroptosis, namely, sirtuin 1(SIRT1), heat shock protein family A (Hsp70) member 5 (HSPA5), mechanistic target of rapamycin kinase (MTOR), hypoxia inducible factor 1 subunit alpha (HIF1A) and beclin 1 (BECN1), which were verified in an animal model.


Assuntos
Ferroptose , Células-Tronco Mesenquimais , Osteoporose , Animais , Biologia Computacional , Ferroptose/genética , Perfilação da Expressão Gênica/métodos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteoporose/genética , Osteoporose/metabolismo
17.
J Cell Mol Med ; 26(21): 5391-5402, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36172879

RESUMO

The dysregulation of lipid metabolic pathways (cholesterol uptake and efflux) in macrophages results in the formation of lipid-dense macrophages, named foam cells, that participate in plaque formation. NPY binding to NPY receptors in macrophages can modulate cell functions and affect the process of atherosclerotic plaques. The present study aimed to determine whether NPY affects the formation of macrophage-derived foam cells and its underlying mechanisms in macrophages. THP-1-derived macrophages were incubated with oxidized low-density lipoprotein (ox-LDL) and treated with different concentrations of NPY. We analysed the relative levels of proteins related to cholesterol uptake and efflux. We found that NPY effectively increased cholesterol uptake and intracellular cholesterol content via the Y1 and Y5 receptors, and this effect was blocked by Y1 and Y5 antagonists. Mechanistically, NPY enhanced the expression of SRA and CD36 via the PKC/PPARγ pathways, promoting macrophage cholesterol uptake. Moreover, NPY significantly decreased cholesterol efflux to the extracellular cholesterol acceptors ApoA1 and HDL in macrophages. NPY mediated decreases in ABCA1, ABCG1 and SR-BI expression through the inhibition of the JAK/STAT3 pathways. Our results suggest that NPY binding to the Y1 and Y5 receptors enhances foam cell formation by regulating cholesterol uptake and efflux in macrophages.


Assuntos
Aterosclerose , Células Espumosas , Humanos , Células Espumosas/metabolismo , Neuropeptídeo Y/farmacologia , Lipoproteínas LDL/farmacologia , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Colesterol/metabolismo , Antígenos CD36/metabolismo , Aterosclerose/metabolismo
18.
Front Med (Lausanne) ; 9: 898606, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35966864

RESUMO

Introduction: The response is poorly understood to the third dose in patients with cancer who failed the standard dose of inactivated SARS-CoV-2 vaccines (CoronaVac). We aim to assess the immune response to the third dose and identify whether vitamin D deficiency is associated with serial serologic failure in patients with cancer. Methods: Solid cancer patients (SCP-N) and healthy controls (HCs) who were seronegative after the standard-dose vaccines in our previous study were prospectively recruited, from October 2021 to February 2022, to receive the third dose vaccines and anti-SARS-CoV-2S antibodies were measured. SCP-N who failed the third dose (serial seronegative group, SSG) were matched by propensity scores with the historical standard-dose positive cancer patient group (robust response group, RRG). An exploratory analysis was carried out to validate the role of vitamin D on the serology response. Results: The multi-center study recruited 97 SCP-N with 279 positive controls as RRG and 82 negative controls as HC group. The seroconversion rate after third-dose vaccination was higher in SCP-N than in HC (70.6% vs. 29.4%, p < 0.01). The matched comparison showed that patients in SSG had a significantly lower level of vitamin D and consumption rate than RRG or RRG-B (RRG with third-dose positive) (all p < 0.01). None had serious (over grade II) adverse events after the third dose. Conclusion: Solid cancer patients with second-dose vaccine failure may have a relatively poor humoral response to the third dose of COVID-19 vaccines as compared with the seronegative HC group. The consecutively poor humoral response could be associated with poor vitamin D levels and intake. Vitamin D status and cancer-related immune compromise may jointly affect the humoral response following booster vaccination.

19.
Materials (Basel) ; 15(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35955280

RESUMO

Phosphate crystals attract much attention on account of their rich crystal structures and excellent physical and chemical properties. Herein, Rb3Ti3P5O20 single crystals were grown by the high temperature solution method using Rb2CO3 and NH4H2PO4 as the fluxes. This crystal, with non-centrosymmetric Pca21 space group, presents a three-dimensional framework structure composed of [TiO6] octahedron, [PO4] tetrahedra, and [P2O7] dimers. The electronic structure was measured via X-ray photoelectron spectroscopy. The measurements found that Rb3Ti3P5O20 has stronger Ti-O ionic bonding properties and weaker P-O covalent bonding properties compared to RbTiOPO4. Optical measurements indicated that Rb3Ti3P5O20 has a 3.54 eV band gap and a wide transmission range (0.33-4.5 µm). Theoretical calculations showed that Rb3Ti3P5O20 crystals have a moderate birefringence of 0.079 at 1064 nm. In addition, the relationship of the structure-property was studied using first-principles method. The results demonstrated that TiO6 octahedron played a significant role for the optical properties.

20.
Nano Lett ; 22(16): 6484-6491, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35926195

RESUMO

The combination of nontrivial topology, magnetism, and superconductivity could offer the potential to realize exotic excitations of quasiparticles. MnBi2Te4, as an intrinsic magnetic topological insulator, may be a good platform to create Majorana fermions if coupled to an s-wave superconductor. Here, we report the transport properties of a MnBi2Te4-NbN hybrid device. This device exhibits clear Coulomb blockade oscillations. We observe a large zero-bias conductance peak that exists over considerable changes in gate voltage, magnetic field, and temperature, which is interpreted as a not fully developed supercurrent. The zero-bias peak shows a nonmonotonic evolution with a magnetic field and an abrupt π phase shift with changing temperature. Zero-energy bound states and a topological phase transition may exist in this hybrid system. Our results provide the first experimental investigation into the properties of the intrinsic magnetic topological insulator/superconductor hybrid structures modulated by the Coulomb blockade effect.

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