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1.
Int Immunopharmacol ; 133: 111877, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38608440

RESUMO

The gut microbiome plays an important role in tumor growth by regulating immune cell function. However, the role of the gut microbiome-mediated monocytes in liver metastasis remains unclear. In this study, we found that fecal microbiome transplantation (FMT) from the stool of patients with liver metastasis (LM) significantly promoted liver metastasis compared with healthy donors (HD). Monocytes were upregulated in liver tissues by the CCL2/CCR2 axis in LM patients' stool transplanted mouse model. CCL2/CCR2 inhibition and monocyte depletion significantly suppress liver metastasis. FMT using LM patients' stool enhanced the plasma lipopolysaccharides (LPS) concentration. The LPS/TLR4 signaling pathway is crucial for gut microbiome-mediated liver metastasis. These results indicated that monocytes contribute to liver metastasis via the CCL2/CCR2 axis.

2.
Cell Death Discov ; 10(1): 167, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589400

RESUMO

The neurotoxic α-synuclein (α-syn) oligomers play an important role in the occurrence and development of Parkinson's disease (PD), but the factors affecting α-syn generation and neurotoxicity remain unclear. We here first found that thrombomodulin (TM) significantly decreased in the plasma of PD patients and brains of A53T α-syn mice, and the increased TM in primary neurons reduced α-syn generation by inhibiting transcription factor p-c-jun production through Erk1/2 signaling pathway. Moreover, TM decreased α-syn neurotoxicity by reducing the levels of oxidative stress and inhibiting PAR1-p53-Bax signaling pathway. In contrast, TM downregulation increased the expression and neurotoxicity of α-syn in primary neurons. When TM plasmids were specifically delivered to neurons in the brains of A53T α-syn mice by adeno-associated virus (AAV), TM significantly reduced α-syn expression and deposition, and ameliorated the neuronal apoptosis, oxidative stress, gliosis and motor deficits in the mouse models, whereas TM knockdown exacerbated these neuropathology and motor dysfunction. Our present findings demonstrate that TM plays a neuroprotective role in PD pathology and symptoms, and it could be a novel therapeutic target in efforts to combat PD. Schematic representation of signaling pathways of TM involved in the expression and neurotoxicity of α-syn. A TM decreased RAGE, and resulting in the lowered production of p-Erk1/2 and p-c-Jun, and finally reduce α-syn generation. α-syn oligomers which formed from monomers increase the expression of p-p38, p53, C-caspase9, C-caspase3 and Bax, decrease the level of Bcl-2, cause mitochondrial damage and lead to oxidative stress, thus inducing neuronal apoptosis. TM can reduce intracellular oxidative stress and inhibit p53-Bax signaling by activating APC and PAR-1. B The binding of α-syn oligomers to TLR4 may induce the expression of IL-1ß, which is subsequently secreted into the extracellular space. This secreted IL-1ß then binds to its receptor, prompting p65 to translocate from the cytoplasm into the nucleus. This translocation downregulates the expression of KLF2, ultimately leading to the suppression of TM expression. By Figdraw.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38492162

RESUMO

PURPOSE: Depression is one of the main psychological responses experienced by patients with breast cancer perioperatively. Therefore, this review aimed to synthesize the prevalence rate of depression preoperatively among patients with breast cancer. METHODS: Six databases were searched for published articles, which recruited female patients aged 18 years and above, diagnosed with breast cancer and planned for breast surgery. Grey literatures were searched from ProQuest Theses and Dissertations, Science.gov and CogPrints. Studies published in English from the inception of databases to January 2023 were considered. Two reviewers screened, extracted, and appraised the data independently. Joanna Briggs Institute data collection form was used for data collection. Hoy's Risk of Bias Tool was utilized to assess the individual study's quality. Review Manager 5.4 software was utilized for meta-analysis. Subgroup analyses were conducted to explore the reasons for any heterogeneity. Publication bias was evaluated by Egger's test and funnel plot. RESULTS: Twenty studies involving 32,143 patients with breast cancer were included. Meta-analyses revealed an overall preoperative prevalence of 30% among all studies. Subgroup analyses showed that studies conducted in the Middle East and North Africa used purposive sampling, with patients undergoing mastectomy and lumpectomy and with moderate risk of bias reported higher prevalence of preoperative depression (54%, 44%, 40%, and 49%, respectively) as compared to other respective subgroups. CONCLUSION: The high prevalence of preoperative depression among women with breast cancer indicated the need for health care professionals to provide more psychological support to them.

4.
Value Health ; 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38467187

RESUMO

OBJECTIVES: This review aims to examine the ceiling effects of EQ-5D-3L (3L) and EQ-5D-5L (5L) in general adult populations and identify the factors influencing these effects. METHODS: We searched 8 databases for observational studies published in English from inception to 24 July 2023. Ceiling effects were calculated by dividing the number of participants reporting full health at dimension or profile level by the total sample size. Subgroup analysis and meta-regression using the metafor package in R software were performed. RESULTS: We identified 94 studies from 70 articles, including 4 543 647 adults across 37 countries. The global pooled proportion of individuals reporting full health ("11111") was 56% (95% CI 51%-62%) for 3L and 49% (95% CI 44%-54%) for 5L. The self-care dimension showed the highest ceiling effects (3L: 97%; 5L: 94%), whereas pain/discomfort had the lowest (3L: 69%; 5L: 60%). The ceiling effects in East/South-East Asia were higher than in Europe by 25% (95% CI 18%-32%) in 3L and 9% (95% CI -2%-20%) in 5L. Adjusting for mean age and proportion of males, significant regional differences persisted in the overall profile level of 3L, in all 3L dimensions (except for self-care), and 5L dimensions (except for pain/discomfort and anxiety/depression). CONCLUSIONS: This review highlights significant ceiling effects in the EQ-5D, especially in Asian populations. The 5L version exhibited fewer ceiling effects than the 3L, indicating its superiority for general population surveys. Further research is crucial to understand the disparities in self-reported health outcomes between Asians and other populations.

5.
J Adv Res ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38471647

RESUMO

INTRODUCTION: Phosphatidylinositol 3-kinases (PI3Ks) overexpression can elicit cellular homeostatic dysregulation, which further contributes to tumorigenesis, with PI3Kα emerging as the most prevalent mutant isoform kinase among PI3Ks. Therefore, selective inhibitors targeting PI3Kα have attracted considerable interest in recent years. Molecular hybridization, with the advantage of simplified pharmacokinetics and drug-drug interactions, emerged as one of the important avenues for discovering potential drugs. OBJECTIVES: This study aimed to construct PI3Kα inhibitors by hybridization and investigate their antitumor activity and mechanism. METHODS: 26 quinazoline-2-indolinone derivatives were obtained by molecular hybridization, and their structure-activity relationship was analyzed by MTT, in vitro kinase activity and molecular docking. The biological evaluation of compound 8 was performed by transwell, flow cytometry, laser scanning confocal microscopy, Western blot, CTESA and immunohistochemistry. RESULTS: Here, we employed molecular hybridization methods to construct a series of quinazoline-2-indolinone derivatives as PI3Kα selective inhibitors. Encouragingly, representative compound 8 exhibited a PI3Kα enzymatic IC50 value of 9.11 nM and 10.41/16.99/37.53-fold relative to the biochemical selectivity for PI3Kß/γ/δ, respectively. Moreover, compound 8 effectively suppressed the viability of B16, HCT116, MCF-7, H22, PC-3, and A549 cells (IC50 values: 0.2 µM âˆ¼ 0.98 µM), and dramatically inhibited the proliferation and migration of NSCLC cells, as well as induced mitochondrial apoptosis through the PI3K/Akt/mTOR pathway. Importantly, compound 8 demonstrated potent in vivo anti-tumor activity in non-small cell lung cancer mouse models without visible toxicity. CONCLUSIONS: This study presented a new avenue for the development of PI3Kα inhibitors and provided a solid foundation for novel QHIDs as potential future therapies for the treatment of NSCLC.

6.
Ann Biomed Eng ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530535

RESUMO

In virtue of a curved insertion path inside tissues, needle steering techniques have revealed the potential with the assistance of medical robots and images. The superiority of this technique has been preliminarily verified with several maneuvers: target realignment, obstacle circumvention, and multi-target access. However, the momentum of needle steering approaches in the past decade leads to an open question-"How to choose an applicable needle steering approach for a specific clinical application?" This survey discusses this question in terms of design choices and clinical considerations, respectively. In view of design choices, this survey proposes a hierarchical taxonomy of current needle steering approaches. Needle steering approaches of different manipulations and designs are classified to systematically review the design choices and their influences on clinical treatments. In view of clinical consideration, this survey discusses the steerability and acceptability of the current needle steering approaches. On this basis, the pros and cons of the current needle steering approaches are weighed and their suitable applications are summarized. At last, this survey concluded with an outlook of the needle steering techniques, including the potential clinical applications and future developments in mechanical design.

7.
Nat Commun ; 15(1): 2614, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521785

RESUMO

Recycling vanadium from alternative sources is essential due to its expanding demand, depletion in natural sources, and environmental issues with terrestrial mining. Here, we present a complexation-precipitation method to selectively recover pentavalent vanadium ions, V(V), from complex metal ion mixtures, using an acid-stable metal binding agent, the cyclic imidedioxime, naphthalimidedioxime (H2CIDIII). H2CIDIII showed high extraction capacity and fast binding towards V(V) with crystal structures showing a 1:1 M:L dimer, [V2(O)3(C12H6N3O2)2]2-, 1, and 1:2 M:L non-oxido, [V(C12H6N3O2)2] ̶ complex, 2. Complexation selectivity studies showed only 1 and 2 were anionic, allowing facile separation of the V(V) complexes by pH-controlled precipitation, removing the need for solid support. The tandem complexation-precipitation technique achieved high recovery selectivity for V(V) with a selectivity coefficient above 3 × 105 from synthetic mixed metal solutions and real oil sand tailings. Zebrafish toxicity assay confirmed the non-toxicity of 1 and 2, highlighting H2CIDIII's potential for practical and large-scale V(V) recovery.

8.
Sci Rep ; 14(1): 5388, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443675

RESUMO

Much evidence has accumulated to show that inflammation and nutritional status are associated with the prognosis of patients with various cancers. The present study was designed to explore the prognostic role of the LANR in NPC patients receiving definitive radiotherapy and to construct a nomogram for predicting patient survival. This study retrospectively reviewed 805 NPC patients (604 in the training cohort and 201 in the validation cohort) who received definitive radiotherapy between January 2013 and December 2019. The clinical data and pretreatment laboratory test data, including lymphocyte count, neutrophil count, and serum ALB concentration, were collected for all patients. The LANR was calculated as the albumin × lymphocyte/neutrophil ratio. Patients in the training cohort and validation cohort were categorized into high-LANR and low-LANR groups according to the corresponding cutoff values. The independent prognostic factors for overall survival (OS), progression-free survival (PFS), relapse-free survival (RFS), and metastasis-free survival (MFS) were evaluated by univariate and multivariate Cox regression analyses, and a nomogram was subsequently constructed. The performance of the nomogram was evaluated by the concordance index (C-index) and calibration curve. A low LANR (< 14.3) was independently associated with worse OS, PFS and MFS in NPC patients. A prognostic prediction nomogram was established based on T stage, N stage, Eastern Cooperative Oncology Group (ECOG) score, treatment modality, and LANR and was validated. The C-indices of the nomograms for OS and PFS in the training cohort were 0.729 and 0.72, respectively. The C-indices of the nomograms for OS and PFS in the validation cohort were 0.694 and 0.695, respectively. The calibration curve revealed good consistency between the actual survival and the nomogram prediction. Patients with NPC with low pretreatment LANR had a poor prognosis. The nomogram established on the basis of the LANR was efficient and clinically useful for predicting survival in NPC patients who underwent definitive radiotherapy.


Assuntos
Neoplasias Nasofaríngeas , Nomogramas , Humanos , Neutrófilos , Carcinoma Nasofaríngeo/radioterapia , Estudos Retrospectivos , Prognóstico , Linfócitos , Albuminas , Neoplasias Nasofaríngeas/radioterapia
9.
iScience ; 27(3): 109213, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439953

RESUMO

Patients with Graves' disease (GD) can develop Graves' ophthalmopathy (GO), but the underlying pathological mechanisms driving this development remain unclear. In our study, which included patients with GD and GO, we utilized single-cell RNA sequencing (scRNA-seq) and multiplatform analyses to investigate CD169+ classical monocytes, which secrete proinflammatory cytokines and are expanded through activated interferon signaling. We found that CD169+ clas_mono was clinically significant in predicting GO progression and prognosis, and differentiated into CD169+ macrophages that promote inflammation, adipogenesis, and fibrosis. Our murine model of early-stage GO showed that CD169+ classical monocytes accumulated in orbital tissue via the Cxcl12-Cxcr4 axis. Further studies are needed to investigate whether targeting circulating monocytes and the Cxcl12-Cxcr4 axis could alleviate GO progression.

10.
Science ; 383(6683): 634-639, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38330133

RESUMO

The interface between two different materials can show unexpected quantum phenomena. In this study, we used molecular beam epitaxy to synthesize heterostructures formed by stacking together two magnetic materials, a ferromagnetic topological insulator (TI) and an antiferromagnetic iron chalcogenide (FeTe). We observed emergent interface-induced superconductivity in these heterostructures and demonstrated the co-occurrence of superconductivity, ferromagnetism, and topological band structure in the magnetic TI layer-the three essential ingredients of chiral topological superconductivity (TSC). The unusual coexistence of ferromagnetism and superconductivity is accompanied by a high upper critical magnetic field that exceeds the Pauli paramagnetic limit for conventional superconductors at low temperatures. These magnetic TI/FeTe heterostructures with robust superconductivity and atomically sharp interfaces provide an ideal wafer-scale platform for the exploration of chiral TSC and Majorana physics.

11.
Heliyon ; 10(2): e24804, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38312571

RESUMO

Background: Blood-based immune-inflammation indexes have been widely used to predict survival in a variety of cancers. In this research, we seeked to evaluate a novel immune-inflammation marker, named the pan-immune-inflammation value (PIV), in patients with nasopharyngeal carcinoma (NPC) undergoing definitive radiotherapy. Methods: A group of 377 patients with NPC was retrospectived analyzed. Clinical data and laboratory data were collected. Receiver operating characteristic (ROC) curve analysis was performed in order to determine the optimal PIV cut-off value. Survival curves were estimated by Kaplan-Meier method, and prognostic variables were identified using a Cox regression model. Additionally, we developed a nomogram and assessed its acuracy using the concordance index (C-index) and a calibration curve. Results: The optimal PIV cut-off value was 146.24 according to ROC analysis. High PIV was related to poorer Eastern Cooperative Oncology Group Performance Status (ECOG PS) score (p = 0.017), more advanced T (p<0.001) and clinical stages (p = 0.024). In univariate analysis, older Age, poorer ECOG PS, higher Epstein-Barr virus DNA (EBV-DNA), advanced T, N and clinical stage, and higher PIV levels were related to patients' poorer overall survival (OS). Poorer ECOG PS, higher EBV-DNA, later T stage, later clinical stage, and higher PIV were associated with patients' poorer progression free survival (PFS). Male sex and later T stage were associated with patients' poorer locoregional recurrence free survival (LRRFS). Poorer ECOG PS, higher EBV-DNA, later T stage, later clinical stage, and higher PIV were associated with patients' poorer distant metastasis free survival (DMFS). Multivariate analysis demonstrated that PIV was an independent prognostic index for OS (HR 2.231, 95 % CI 1.241-4.011, P = 0.007), PFS (HR 1.664, 95 % CI 1.003-2.760, P = 0.049), and DMFS(HR 2.081, 95 % CI 1.071-4.044, P = 0.031). Nomogram C-indexes for the nomogram of OS were 0.684, and PFS were 0.62, respectively. Survival predictions and actual survival were consistent according to the calibration curve. Conclusions: Pre-treatment PIV is a promising biomarker for predicting survival in patients with NPC.

12.
Ageing Res Rev ; 95: 102243, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395198

RESUMO

Frailty is a prevalent condition amongst older adults, significantly affecting their quality of life. The FRAIL tool has been purposefully designed for clinical application by assisting healthcare professionals in identifying and managing frailty-related issues in older adults, making it a preferred choice for assessing frailty across diverse older populations. This review aimed to synthesize the measurement properties and feasibility of FRAIL. Guided by COSMIN guidelines, seven databases were searched from inception to 31 Mar 2023. The measurement properties were extracted for quality appraisal of the populations in the studied samples. Where possible, random-effects meta-analysis and meta-regression were used for quantitative synthesis. Eighteen articles containing 273 tests were drawn from 14 different populations. We found that populations testing for criterion validity had high-quality ratings, while construct validity ratings varied based on health status and geographical region. Test-retest reliability had sufficient quality ratings, while scale agreement had sufficient ratings in only four out of 14 populations tested. Responsiveness ratings were insufficient in seven out of eight populations, with inconsistent ratings in one population. Our analysis of missing data across three articles showed a 16.3% rate, indicating good feasibility of the FRAIL. FRAIL is a feasible tool for assessing frailty of older adults in community settings, with good criterion validity and test-retest reliability. However, more research is needed on construct validity and responsiveness.


Assuntos
Fragilidade , Humanos , Idoso , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Idoso Fragilizado , Qualidade de Vida , Reprodutibilidade dos Testes , Estudos de Viabilidade
13.
Obes Rev ; 25(5): e13699, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38296771

RESUMO

The prevalence of overweight and obesity has continued to increase globally, and one-size-fits-all dietary recommendations may not be suitable for different individual characteristics. A personalized nutrition intervention may be a potential solution. This review aims to evaluate the effects of the technology-delivered personalized nutrition intervention on energy, fat, vegetable, and fruit intakes among adults with overweight and obesity. A three-step comprehensive search strategy was performed from 10 databases and seven clinical registries in published and unpublished trials. A total of 46 randomized controlled trials (RCTs) involving 19,670 adults with overweight and obesity from 14 countries are included. Subgroup and meta-regression analyses were conducted. Meta-analyses showed a reduction of energy intake (-128.05, 95% CI: -197.08, -59.01) and fat intake (-1.81% energy/days, 95% CI: -3.38, -0.24, and -0.19 scores, 95% CI: -0.40, 0.02) in the intervention compared with the comparator. Significant improvements in vegetable and fruit intakes with 0.12-0.15 servings/day were observed in the intervention. Combined one- and two-way interactions had a greater effect on energy intake reduction compared with their counterparts. Meta-regression analyses revealed that no significant covariates were found. Given that the certainty of the evidence was rated as low or very low, further well-designed RCTs with long-term follow-up are warranted.


Assuntos
Dieta , Sobrepeso , Adulto , Humanos , Obesidade , Verduras , Ingestão de Energia
14.
Cell Mol Life Sci ; 81(1): 57, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279052

RESUMO

The Wnt/ß-catenin pathway is critical to maintaining cell fate decisions. Recent study showed that liquid-liquid-phase separation (LLPS) of Axin organized the ß-catenin destruction complex condensates in a normal cellular state. Mutations inactivating the APC gene are found in approximately 80% of all human colorectal cancer (CRC). However, the molecular mechanism of the formation of ß-catenin destruction complex condensates organized by Axin phase separation and how APC mutations impact the condensates are still unclear. Here, we report that the ß-catenin destruction complex, which is constructed by Axin, was assembled condensates via a phase separation process in CRC cells. The key role of wild-type APC is to stabilize destruction complex condensates. Surprisingly, truncated APC did not affect the formation of condensates, and GSK 3ß and CK1α were unsuccessfully recruited, preventing ß-catenin phosphorylation and resulting in accumulation in the cytoplasm of CRCs. Besides, we propose that the phase separation ability of Axin participates in the nucleus translocation of ß-catenin and be incorporated and concentrated into transcriptional condensates, affecting the transcriptional activity of Wnt signaling pathway.


Assuntos
Complexo de Sinalização da Axina , beta Catenina , Humanos , Complexo de Sinalização da Axina/genética , Proteína Axina/genética , Proteína Axina/metabolismo , beta Catenina/genética , beta Catenina/metabolismo , 60422 , Mutação/genética , Via de Sinalização Wnt/genética , Proteína da Polipose Adenomatosa do Colo/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo
15.
Chem Commun (Camb) ; 60(12): 1623-1626, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38230709

RESUMO

P-Stereogenic phosphorus compounds are important structural elements in chiral ligands or organocatalysts. Herein, we report a Pd(II)-catalyzed enantioselective C-H olefination toward the synthesis of P-stereogenic phosphinamides using cheap commercially available L-pGlu-OH as a chiral ligand. A broad range of P-stereogenic phosphinamides were gained in good yields with high enantioselectivities (33 examples, up to 77% yield, 99% ee) via desymmetrization and kinetic resolution.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 310: 123934, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38266603

RESUMO

Excessive use of antithyroid drug methimazole (MMI) in pharmaceutical samples can cause hypothyroidism and symptoms of metabolic decline. Hence, it is urgent to develop rapid, low cost and accurate colorimetric method with peroxidase-like nanozymes for determination of MMI in medical, nutrition and pharmaceutical studies. Herein, Fe single atoms were facilely encapsulated into N, P-codoped carbon nanosheets (Fe SAs/NP-CSs) by a simple pyrolysis strategy, as certified by a series of characterizations. UV-vis absorption spectroscopy was employed to illustrate the high peroxidase-mimicking activity of the resultant Fe SAs/NP-CSs nanozyme through the typical catalysis of 3,3',5,5'-tetramethylbenzidine (TMB) oxidation. The catalytic mechanism was scrutionously investigated by the fluorescence spectroscopy and electron paramagnetic resonance (EPR) tests. Additionally, the introduced MMI had the ability to reduce the oxidation of TMB (termed oxTMB) as a peroxidase inhibitor, coupled by fading the blue color. By virtue of the above findings, a visual colorimetric sensor was established for dual detection of methimazole (MMI) with a linear scope of 5-50 mM and a LOD of 1.57 mM, coupled by assay of H2O2 at a linear range of 3-50 mM. According to the irreversible oxidation of the drug, its screening with acceptable results was achieved on the sensing platform even in commercial tablets The Fe SAs/NP-CSs nanozyme holds great potential for clinical diagnosis and drug analysis.


Assuntos
Carbono , Colorimetria , Carbono/química , Colorimetria/métodos , Metimazol , Peróxido de Hidrogênio/análise , Peroxidase/metabolismo , Oxirredutases , Peroxidases , Corantes , Preparações Farmacêuticas
17.
Rev Sci Instrum ; 95(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38265278

RESUMO

With the advantages of high energy density, high accuracy, and fast response, smart material-driven electro-hydrostatic actuators (SMEHAs) have attracted significant attention in recent years. However, the low flow rate of SMEHAs constrains their application. One potential solution to enhance the flow rate is to increase the number of smart material-actuated pumps. In view of this, this paper proposes a new configuration of an electro-hydrostatic actuator equipped with four magnetostrictive-actuated pumps (FMEHA) to achieve a large flow rate. The mathematical model of the FMEHA is established to investigate the driving phase matching between pumps and the active flow distribution valve. The physical prototype of FMEHA is fabricated. Simulations and experiments are conducted to assess its performance under various driving parameters, including the number of pumps, driving phase, frequency, and amplitude. The optimal driving parameters for the FMEHA are determined based on the results obtained. Experimental findings demonstrate that with a driving phase of 340°, a frequency of 250 Hz, and an amplitude of 20 A, the FMEHA achieves a maximum flow rate of 6.2 l/min.

18.
Nat Mater ; 23(1): 58-64, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37857889

RESUMO

A quantum anomalous Hall (QAH) insulator is a topological phase in which the interior is insulating but electrical current flows along the edges of the sample in either a clockwise or counterclockwise direction, as dictated by the spontaneous magnetization orientation. Such a chiral edge current eliminates any backscattering, giving rise to quantized Hall resistance and zero longitudinal resistance. Here we fabricate mesoscopic QAH sandwich Hall bar devices and succeed in switching the edge current chirality through thermally assisted spin-orbit torque (SOT). The well-quantized QAH states before and after SOT switching with opposite edge current chiralities are demonstrated through four- and three-terminal measurements. We show that the SOT responsible for magnetization switching can be generated by both surface and bulk carriers. Our results further our understanding of the interplay between magnetism and topological states and usher in an easy and instantaneous method to manipulate the QAH state.

19.
Neurosci Bull ; 40(3): 293-309, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37639183

RESUMO

The cytochrome P450 proteins (CYP450s) have been implicated in catalyzing numerous important biological reactions and contribute to a variety of diseases. CYP26A1, a member of the CYP450 family, carries out the oxidative metabolism of retinoic acid (RA), the active metabolite of vitamin A. Here we report that CYP26A1 was dramatically upregulated in the spinal cord after spinal nerve ligation (SNL). CYP26A1 was mainly expressed in spinal neurons and astrocytes. HPLC analysis displayed that the content of all-trans-RA (at-RA), the substrate of CYP26A1, was reduced in the spinal cord on day 7 after SNL. Inhibition of CYP26A1 by siRNA or inhibition of CYP26A1-mediated at-RA catabolism by talarozole relieved the SNL-induced mechanical allodynia during the maintenance phase of neuropathic pain. Talarozole also reduced SNL-induced glial activation and proinflammatory cytokine production but increased anti-inflammatory cytokine (IL-10) production. The RA receptors RARα, RXRß, and RXRγ were expressed in spinal neurons and glial cells. The promoter of Il-10 has several binding sites for RA receptors, and at-RA directly increased Il-10 mRNA expression in vitro. Finally, intrathecal IL-10 attenuated SNL-induced neuropathic pain and reduced the activation of astrocytes and microglia. Collectively, the inhibition of CYP26A1-mediated at-RA catabolism alleviates SNL-induced neuropathic pain by promoting the expression of IL-10 and suppressing glial activation. CYP26A1 may be a potential therapeutic target for the treatment of neuropathic pain.


Assuntos
Interleucina-10 , Neuralgia , Humanos , Interleucina-10/metabolismo , Ácido Retinoico 4 Hidroxilase/metabolismo , Medula Espinal/metabolismo , Neuralgia/metabolismo , Citocinas/metabolismo , Hiperalgesia/metabolismo
20.
Biotechnol J ; 19(1): e2300085, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37789647

RESUMO

D-Allulose is an ultra-low-calorie sweetener with broad market prospects in the fields of food, beverage, health care, and medicine. The fermentative synthesis of D-allulose is still under development and considered as an ideal route to replace enzymatic approaches for large-scale production of D-allulose in the future. Generally, D-allulose is synthesized from D-fructose through Izumoring epimerization. This biological reaction is reversible, and a high temperature is beneficial to the conversion of D-fructose. Mild cell growth conditions seriously limit the efficiency of producing D-allulose through fermentation. FryABC permease was identified to be responsible for the transport of D-allulose in Escherichia coli by comparative transcriptomic analysis. A cell factory was then developed by expression of ptsG-F, dpe, and deletion of fryA, fruA, manXYZ, mak, and galE. The results show that the newly engineered E. coli was able to produce 32.33 ± 1.33 g L-1 of D-allulose through a unique thermo-swing fermentation process, with a yield of 0.94 ± 0.01 g g-1 on D-fructose.


Assuntos
Escherichia coli , Engenharia Metabólica , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Frutose/metabolismo , Proteínas de Membrana Transportadoras/metabolismo
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