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1.
Eur Spine J ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38816538

RESUMO

PURPOSE: Postoperative surgical site infection is one of the most serious complications following spine surgery. Previous studies have reported Modic changes (MC) represent a subclinical infection. This study aims to investigate the relation between Modic changes and surgical site infection after posterior lumbar fusion surgery. METHODS: We retrospectively reviewed the records of 424 patients who received posterior lumbar fusion. Preoperative clinical and radiological parameters were recorded. Primary outcome was the rate of postoperative surgical site infection. Covariates included age, body mass index (BMI), sex, hypertension, diabetes mellitus, chronic heart failure, Pfirrmann classification, fused levels, and operation duration. The presence of Modic changes was used as an exposition variable, and adjusted for other risk factors in multivariate analyses. RESULTS: Of the 424 patients, 30 (7%) developed an acute surgical site infection. Infection had no relation to age, sex, BMI, and comorbidities. There were 212 (50%) patients with MC, and 23 (10.8%) had a surgical site infection, compared to 212 (50%) patients without MC in which there were 7 (3.3%) surgical site infections. MC was associated with surgical site infection in univariate analysis (odds ratio [OR] = 3.56, 95% confidence interval [CI]: 1.49-8.50, p = 0.004) and multivariate logistic regression analysis (OR = 3.05, 95% CI: 1.26-7.37, p = 0.013). There was statistically significant between specific type (p = 0.035) and grade of MCs (p = 0.0187) and SSI. CONCLUSIONS: MCs may be a potential risk factor for SSI following posterior lumbar spinal intervertebral fusion. Type I and grade C MCs showed a higher infection rate compared with other MC types and grades.

2.
Biochem Biophys Res Commun ; 711: 149888, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38603833

RESUMO

OBJECTIVE: To investigate the effect of intermittent parathyroid hormone (iPTH) administration on pathological new bone formation during treatment of ankylosing spondylitis-related osteoporosis. METHODS: Animal models with pathological bone formation caused by hypothetical AS pathogenesis received treatment with iPTH. We determined the effects of iPTH on bone loss and the formation of pathological new bone with micro-computed tomography (micro-CT) and histological examination. In addition, the tamoxifen-inducible conditional knockout mice (CAGGCre-ERTM; PTHflox/flox, PTH-/-) was established to delete PTH and investigate the effect of endogenous PTH on pathological new bone formation. RESULTS: iPTH treatment significantly improved trabecular bone mass in the modified collagen-induced arthritis (m-CIA) model and unbalanced mechanical loading models. Meanwhile, iPTH treatment did not enhance pathological new bone formation in all types of animal models. Endogenous PTH deficiency had no effects on pathological new bone formation in unbalanced mechanical loading models. CONCLUSION: Experimental animal models of AS treated with iPTH show improvement in trabecular bone density, but not entheseal pathological bone formation,indicating it may be a potential treatment for inflammatory bone loss does in AS.


Assuntos
Osteogênese , Hormônio Paratireóideo , Animais , Hormônio Paratireóideo/administração & dosagem , Hormônio Paratireóideo/farmacologia , Hormônio Paratireóideo/uso terapêutico , Osteogênese/efeitos dos fármacos , Camundongos , Osteoporose/tratamento farmacológico , Osteoporose/patologia , Camundongos Knockout , Masculino , Microtomografia por Raio-X , Espondilite Anquilosante/tratamento farmacológico , Espondilite Anquilosante/patologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Densidade Óssea/efeitos dos fármacos
3.
STAR Protoc ; 5(1): 102820, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38198280

RESUMO

DNA G-quadruplex (G4) is a non-canonical four-stranded secondary structure that has been shown to play a role in epigenetic modulation of gene expression. Here, we present a primer on phenotype-specific profiling of DNA G-quadruplex-regulated genes. We provide guidance on in silico exploration of G4-related genes and phenotypes, and in vitro and in vivo validation of the relationship between G4 and phenotype. We describe commonly utilized techniques and detail critical steps involved in determining the phenotype-specific G4-regulated genes for subsequent investigations.


Assuntos
DNA , Quadruplex G , DNA/genética , Fenótipo
4.
JOR Spine ; 7(1): e1284, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38249720

RESUMO

Background: An experimental study was performed to improve the anterior approach model of intervertebral disc degeneration (IVDD). Objective: The aims of this study were to investigate the anterior approach model of IVDD for the cause of death, phenotypes, and underlying mechanisms of low back pain in mice. Method: In this study, we conducted an anterior puncture procedure on a cohort of 300 C57BL/6J mice that were 8 weeks old. Our investigation focused on exploring the causes of death in the study population (n = 300) and assessing the time-course changes in various parameters, including radiographical, histological, immunofluorescence, and immunohistochemistry analyses (n = 10). Additionally, we conducted behavioral assessments on a subset of the animals (n = 30). Results: Transverse vertebral artery rupture is a major factor in surgical death. Radiographical analyses showed that the hydration of the nucleus pulposus began to decrease at 2 weeks after puncture and obviously disappeared over 4 weeks. 3D-CT showed that disc height was significantly decreased at 4 weeks. Osteophyte at the anterior vertebral rims was observed at 2 weeks after the puncture. As the time course increased, histological analyses showed progressive disruption of the destruction of the extracellular matrix and increased secretion of inflammatory cytokines and apoptosis. Behavioral signs of low back pain were increased between the puncture and sham groups at 4 weeks. Conclusion: The improvement of anterior intervertebral disc approach model in mice will be useful to investigate underlying mechanisms and potential therapeutic strategies for behavior and phenotypes. Furthermore, the application of vibrational pre-treatment can be used to increase the sensitivity of axial back pain in the model, thereby providing researchers with a reliable method for measuring this critical phenotype.

5.
Nat Commun ; 15(1): 47, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167807

RESUMO

Intervertebral disc degeneration is a natural process during aging and a leading cause of lower back pain. Here, we generate a comprehensive atlas of nucleus pulposus cells using single-cell RNA-seq analysis of human nucleus pulposus tissues (three males and four females, age 41.14 ± 18.01 years). We identify fibrotic late-stage nucleus pulposus cells characterized by upregulation of serglycin expression which facilitate the local inflammatory response by promoting the infiltration of inflammatory cytokines and macrophages. Finally, we discover that daphnetin, a potential serglycin ligand, substantially mitigates the local inflammatory response by downregulating serglycin expression in an in vivo mouse model, thus alleviating intervertebral disc degeneration. Taken together, we identify late-stage nucleus pulposus cells and confirm the potential mechanism by which serglycin regulates intervertebral disc degeneration. Our findings indicate that serglycin is a latent biomarker of intervertebral disc degeneration and may contribute to development of diagnostic and therapeutic strategies.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Masculino , Feminino , Humanos , Animais , Camundongos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Degeneração do Disco Intervertebral/metabolismo , Núcleo Pulposo/metabolismo , Proteoglicanas , Biomarcadores , Disco Intervertebral/metabolismo
6.
J Orthop Res ; 42(1): 172-182, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37377113

RESUMO

This study investigated the molecular mechanism by which acetylshikonin inhibits SOX4 expression via the PI3K/Akt pathway to delay intervertebral disc degeneration (IVDD) and low back pain (LBP). Bulk RNA-seq, RT-qPCR, Western blot analysis, immunohistochemical staining, small interfering RNA (siSOX4), lentivirus (lentiv-SOX4hi ), and imaging techniques were used to assess SOX4 expression and validate its upstream regulatory pathway. Acetylshikonin and siSOX4 were injected into the IVD to measure IVDD. SOX4 expression significantly increased in degenerated IVD tissues. TNF-α increased SOX4 expression and apoptosis-related proteins in nucleus pulposus cells (NPCs). siSOX4 reduced TNF-α-induced NPCs apoptosis, while Lentiv-SOX4hi increased it. The PI3K/Akt pathway was significantly correlated with SOX4, and acetylshikonin upregulated PI3K/Akt pathway while inhibiting SOX4 expression. In the anterior puncture IVDD mouse model, SOX4 expression was upregulated, and acetylshikonin and siSOX4 delayed IVDD-induced LBP. Acetylshikonin delays IVDD-induced LBP by inhibiting SOX4 expression through the PI3K/Akt pathway. These findings offer potential therapeutic targets for future treatments.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Dor Lombar , Núcleo Pulposo , Animais , Camundongos , Apoptose , Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/tratamento farmacológico , Dor Lombar/tratamento farmacológico , Núcleo Pulposo/metabolismo , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fator de Necrose Tumoral alfa/metabolismo
7.
Small ; 20(8): e2306854, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37828639

RESUMO

Recently, the power conversion efficiency (PCE) of organic solar cells (OSCs) has increased dramatically, making a big step toward the industrial application of OSCs. Among numerous OSCs, benzodithiophene (BDT)-based OSCs stand out in achieving efficient PCE. Notably, single-junction OSCs using BDT-based polymers as donor materials have completed a PCE of over 19%, indicating a dramatic potential for preparing high-performance large-scale OSCs. This paper reviews the recent progress of OSCs based on BDT polymer donor materials (PDMs). The development of BDT-based OSCs is concisely summarized. Meanwhile, the relationship between the structure of PDMs and the performance of OSCs is further described in this review. Besides, the development and prospect of single junction OSCs are also discussed.

8.
J Integr Med ; 22(1): 12-21, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38104001

RESUMO

BACKGROUND: Scraping therapy is widely used in treating stage I and II essential hypertension in China. However, there has been no systematic evaluation of the efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential hypertension. SEARCH STRATEGY: Seven electronic databases (PubMed, Scopus, Cochrane Library, Web of Science, EBSCO, China National Knowledge Infrastructure and Wanfang Data electronic databases) were searched from inception to December 2022. Based on the principle of combining subject words with text words, the search strategy was constructed around search terms for "scraping therapy," "scraping," "Guasha," "Gua sha," "hypertension," and "high blood pressure" during the database searches. INCLUSION CRITERIA: Randomized controlled trials (RCTs) were included if they recruited patients with stage I and II essential hypertension and included a scraping therapy intervention. The intervention group received antihypertensive drugs and scraping therapy, while the control group only took antihypertensive drugs. DATA EXTRACTION AND ANALYSIS: Review Manager 5.4.0 and STATA 15.1 were used to enter all the relevant outcome variables to conduct the meta-analysis. The quality of the selected RCTs was assessed using the PEDro scale. The sensitivity analysis was carried out by iteratively excluding individual studies and repeating the analysis to determine the stability of the findings and identify any studies with greater influence on the outcome. Subgroup analysis was performed to find the source of heterogeneity. Funnel plots were used to evaluate the publication bias of included studies. RESULTS: Nine RCTs including 765 participants were selected. Meta-analysis showed that scraping therapy combined with medication had an advantage over the use of medication alone in lowering systolic blood pressure (mean difference [MD] = -5.09, 95% confidence interval [CI] = -6.50 to -3.67, P < 0.001) and diastolic blood pressure (MD = -2.66, 95% CI = -3.17 to -2.14, P < 0.001). Subgroup analysis showed that scraping therapy improved sleep quality in middle-aged patients with hypertension, but the efficacy was better in elderly patients (MD = -7.91, 95% CI = -8.65 to -7.16, P < 0.001) than in middle-aged patients (MD = -2.67, 95% CI = -4.12 to -1.21, P = 0.0003). CONCLUSION: The available evidence indicates that scraping therapy has significant effects on patients with stage I and II hypertension, and it improves sleep quality for elderly patients with hypertension better than for middle-aged ones. Scraping therapy can be an adjunctive treatment for stage I and II essential hypertension. However, further high-quality studies are needed to verify its effectiveness and the best therapeutic strategies. Please cite this article as: Zhu, Z, Wang J, Pan, X. Efficacy of scraping therapy on blood pressure and sleep quality in stage I and II essential hypertension: A systematic review and meta-analysis. J Integr Med. 2024; 22(1): 12-21.


Assuntos
Anti-Hipertensivos , Hipertensão , Pessoa de Meia-Idade , Humanos , Idoso , Pressão Sanguínea , Anti-Hipertensivos/uso terapêutico , Qualidade do Sono , Hipertensão Essencial/tratamento farmacológico , Hipertensão Essencial/induzido quimicamente , Hipertensão/tratamento farmacológico , Hipertensão/induzido quimicamente
9.
Small ; : e2308961, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38059861

RESUMO

Electron transport layers (ETLs) generally contain polar groups for enhancing performance and reducing the work function. Nevertheless, the polar group with high surface energy may cause inferior interfacial compatibility, which challenges the ETLs to balance stability and performance. Here, two conjugated small molecules of ETLs with low surface energy siloxane, namely PDI-Si and PDIN-Si, are synthesized. The siloxane with low surface energy not only enhances the interfacial compatibility between ETLs and active layers but also improves the moisture-proof stability of the device. Impressively, the amine-functionalized PDIN-Si can simultaneously exhibit conspicuous n-type self-doping properties and outstanding moisture-proof stability. The optimization of interfacial contact and morphology enables the PM6:Y6-based OSC with PDIN-Si to achieve a power conversion efficiency (PCE) of 15.87%, which is slightly superior to that of classical ETL PDINO devices (15.27%), and when the PDIN-Si film thickness reaches 28 nm, the PCE remains at 13.19% (≈83%), which indicates that PDIN-Si has satisfactory thickness insensitivity to facilitate roll-to-roll processing. Excitingly, after 120 h of storage in an environment with humidity above 45%, the unencapsulated device with PDIN-Si as ETL remains at 75% of the initial PCE value, while the device with PDINO as ETL is only 50%.

10.
Materials (Basel) ; 16(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37959472

RESUMO

Investigating the constitutive relationship and the damage failure mechanism of solid propellants is of significance for improving the safety, storage period and use efficiency of solid rocket motors. This paper focuses on the complex mechanical response behavior of composite solid propellants under loads and introduces experimental research on quasi-static and dynamic mechanical properties. Limited by the accuracy of instruments and testing methods, the research progress of macroscopic constitutive models, mesoscopic mechanical models and microscopic molecular models is summarized from the perspective of numerical simulations based on model scale and modeling methods. This paper tracks the historical progress of key models and summarizes the main achievements and prospects in this field. The research in this paper has high scientific and theoretical significance and engineering application value. It can provide an important reference and guidance for the structural optimization and performance improvement of solid propellants and lay a solid foundation for the development of solid rocket motors.

11.
Nanomaterials (Basel) ; 13(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37764571

RESUMO

The design of non-buckling interconnects with thick sections has gained important applications in stretchable inorganic electronics due to their simultaneous achievement of high stretchability, low resistance, and low heat generation. However, at the same time, such a design sharply increased the tensile stiffness, which is detrimental to the conformal fit and skin comfort. Introducing the fractal design into the non-buckling interconnects is a promising approach to greatly reduce the tensile stiffness while maintaining other excellent performances. Here, a hierarchical theory is proposed for the tensile stiffness of the non-buckling fractal-inspired interconnects with an arbitrary shape at each order, which is verified by the finite element analysis. The results show that the tensile stiffness of the non-buckling fractal-inspired interconnects decreases with the increase in either the height/span ratio or the number of fractal orders but is not highly correlated with the ratio of the two adjacent dimensions. When the ratio of the two adjacent dimensions and height/span ratio are fixed, the tensile stiffness of the serpentine fractal-inspired interconnect is smaller than that of sinusoidal and zigzag fractal-inspired interconnects. These findings are of great significance for the design of non-buckling fractal-inspired interconnects of stretchable inorganic electronics.

12.
Langmuir ; 39(32): 11317-11328, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37526360

RESUMO

The phase instability of CsPbI3 perovskite quantum dots (PQDs) restricts their practical applications due to the easy conversion from the luminescent cubic phase to the non-luminescent orthorhombic phase. The elemental doping route has been regarded as one of the most effective strategies to achieve high-quality PQDs-based phosphors. Herein, a stoichiometric amount of nickel chloride (NiCl2) has been effectively doped into the CsPbI3 lattice. The incorporation of Ni2+ ions has little effect on the crystal phase, structure, and morphology of the CsPbI3 PQDs but greatly influences their luminescence properties. The Ni2+ doping not only improves the luminescence performance but also greatly enhances the stability against temperature, storage time, and polar solvent. The formation process and luminescence and stability improvement mechanisms have been discussed. Moreover, the influence of a series of other metal chlorides (KCl, NaCl, MgCl2, ZnCl2, SnCl2, and CaCl2) on the luminescence performance of CsPbI3 PQDs has been systematically investigated, revealing that the luminescence intensity increases by introducing CaCl2, SnCl2, or ZnCl2 but decreases after doping MgCl2, NaCl, or KCl into the CsPbI3 lattice. The as-proposed doping strategy may have a significant impact on tackling the intrinsic instability of all-inorganic CsPbX3 PQDs, shedding light on their future applications in light-emitting diode (LED) devices and solid-state lighting.

13.
Materials (Basel) ; 16(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37445042

RESUMO

This study investigated the fracture characteristics of plain concrete and polypropylene fiber-reinforced concrete (PFRC) using pre-notched three-point bending beam tests with the digital speckle correlation method (DSCM). Then, the fracture instability behavior of the two types of beams was simulated in finite elements based on the plastic damage model and the cohesion model, for which the applicability was assessed. Furthermore, the stability of the Big Gang Mountain Dam made from plain concrete or PFRC subjected to the earth-quake loading was simulated with the plastic damage model. The results show that the limiting length of the non-local deformation zone can be used as an indicator of instability damage in a concrete structure. The simulation results of the plastic damage model agreed well with the local deformation in the pre-notched three-point bending beam test obtained from the DSCM. The plastic damage model was found to be capable of describing the residual strength phenomenon, which the cohesive model was not capable of. The damage evolution regions of the PFRC dam are strictly constrained in some regions without the occurrence of the local deformation band across the dam, and PFRC can dramatically reduce the failure risk under earthquake loading. The numerical solution proves that PFRC is an advisable material for avoiding failure in concrete dams.

14.
Polymers (Basel) ; 15(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299338

RESUMO

This study utilizes the genetic algorithm (GA) and Levenberg-Marquardt (L-M) algorithm to optimize the parameter acquisition process for two commonly used viscoelastic models: 2S2P1D and Havriliak-Negami (H-N). The effects of the various combinations of the optimization algorithms on the accuracy of the parameter acquisition in these two constitutive equations are investigated. Furthermore, the applicability of the GA among different viscoelastic constitutive models is analyzed and summarized. The results indicate that the GA can ensure a correlation coefficient of 0.99 between the fitting result and the experimental data of the 2S2P1D model parameters, and it is further proved that the fitting accuracy can be achieved through the secondary optimization via the L-M algorithm. Since the H-N model involves fractional power functions, high-precision fitting by directly fitting the parameters to experimental data is challenging. This study proposes an improved semi-analytical method that first fits the Cole-Cole curve of the H-N model, followed by optimizing the parameters of the H-N model using the GA. The correlation coefficient of the fitting result can be improved to over 0.98. This study also reveals a close relationship between the optimization of the H-N model and the discreteness and overlap of experimental data, which may be attributed to the inclusion of fractional power functions in the H-N model.

15.
Heliyon ; 9(5): e15966, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37215849

RESUMO

Background: Aging confers an increased risk of developing cancer, and the global burden of cancer is cumulating as human longevity increases. Providing adequate care for old patients with rectal cancer is challenging and complex. Method: A total of 428 and 44,788 patients diagnosed with non-metastatic rectal cancer from a referral tertiary care center (SYSU cohort) and the Surveillance Epidemiology and End Results database (SEER cohort) were included. Patients were categorized into old (over 65 years) and young (aged 50-65 years) groups. An age-specific clinical atlas of rectal cancer was generated, including the demographic and clinicopathological features, molecular profiles, treatment strategies, and clinical outcomes. Results: Old and young patients were similar in clinicopathological risk factors and molecular features, including TNM stage, tumor location, tumor differentiation, tumor morphology, lymphovascular invasion, and perineural invasion. However, old patients had significantly worse nutritional status and more comorbidities than young patients. In addition, old age was independently associated with less systemic cancer treatment (adjusted odds ratio 0.294 [95% CI 0.184-0.463, P < 0.001]). We found that old patients had significantly worse overall survival (OS) outcomes in both SYSU (P < 0.001) and SEER (P < 0.001) cohorts. Moreover, the death and recurrence risk of old patients in the subgroup not receiving chemo/radiotherapy (P < 0.001 for OS, and P = 0.046 for time to recurrence [TTR]) reverted into no significant risk in the subgroup receiving chemo/radiotherapy. Conclusions: Although old patients had similar tumor features to young patients, they had unfavorable survival outcomes associated with insufficient cancer care from old age. Specific trials with comprehensive geriatric assessment for old patients are needed to identify the optimal treatment regimens and improve unmet cancer care. Study registration: The study was registered on the research registry with the identifier of researchregistry 7635.

16.
Eur Spine J ; 32(6): 2012-2019, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37027034

RESUMO

PURPOSE: In this study, we intended to investigate the association between immediate postoperative hypoalbuminemia and surgical site infection (SSI), and determine a threshold value for postoperative hypoalbuminemia that can assist in risk stratification in patients after posterior lumbar fusion surgery. METHODS: From January 2017 to December 2021, 466 consecutive patients who underwent posterior lumbar fusion surgery were selected to analyze the relationship between immediate postoperative hypoalbuminemia and SSI. Multivariate logistic regression analysis was performed to identify the independent risk factors of SSI and postoperative hypoalbuminemia. Receiver Operating Characteristic (ROC) analysis was used to determine the optimal value for postoperative hypoalbuminemia, and subsequent grouping was based on the identified threshold. RESULTS: Of the total 466 patients, 25 patients (5.4%) developed SSI after surgery, and lower postoperative albumin (OR: 0.716, 95% CI: 0.611-0.840, p < 0.001) was independently associated with SSI. ROC analysis showed that the cutoff value of postoperative hypoalbuminemia was 32 g/L with a sensitivity of 0.760, specificity of 0.844, and a Youden index of 0.604. Postoperative SSI was more common in patients with postoperative hypoalbuminemia than in those without (21.6% vs. 1.6%, p < 0.001). Age, gender and operative duration were found to be independent predictors of postoperative hypoalbuminemia. CONCLUSIONS: This study showed that immediate postoperative hypoalbuminemia was an independent risk factor for the development of SSI in patients who underwent posterior lumbar fusion. Even in patients with a normal preoperative serum albumin level, there was an increased risk of SSI when the postoperative albumin within 24 h was < 32 g/L.


Assuntos
Hipoalbuminemia , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Hipoalbuminemia/epidemiologia , Fatores de Risco , Albuminas , Estudos Retrospectivos
17.
Anal Chem ; 95(17): 7053-7061, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37080908

RESUMO

False positives and negatives in bioanalytical assays remain a persistent problem. Herein, a multifunctional photoelectrochemical (PEC) biosensor based on ZnIn2S4 (ZIS)/ZnS quantum dots (QDs)@Au-Ag-reversed photocurrent of Cu-metal-organic framework (MOF) coupled with CRISPR/Cas-12a-shearing was innovatively developed for assay of dual targets. First, Cu-MOF as a good PEC material shows cathodic photocurrent. Then, numerous ZIS/ZnS QDs were assembled to the Au-Ag nanoparticles (NPs) to prepare a stable and highly amplified signal probe, which can just match the energy level of Cu-MOFs and realized the polarity-reversed photocurrent of Cu-MOF for the first time. As the empty-core nanostructure of Au-Ag NPs has a high specific surface area and low material density, the bimetallic nanocrystal can much increase the reaction rate and improve the redox efficiency. When target CEA-produced cDNA opened the hairpin DNA (HP1 DNA) on the electrode, the ZIS/ZnS QDs@Au-Ag signal probe was conjugated to the electrode via DNA hybridization, achieving a significantly reversed PEC current for CEA detection. Moreover, the specific binding of kanamycin/aptamer generated the acDNA (activator), which can activate the trans-cleavage activity of the CRISPR-CAS12a system on ssDNA, so the signal probe was sheared and caused the obvious decrease of PEC signal for kanamycin detection. The newly developed ZIS/ZnS QDs@Au-Ag NPs displayed excellent PEC properties and reversed photocurrent to MOF and were combined with the unique CRISPR-Cas12a system to achieve sensitive detection of dual targets, which can open a new polarity-reversed PEC sensing platform for rapid and accurate analysis of multiple targets and can effectively avoid false positives results in clinical testing.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Estruturas Metalorgânicas , Pontos Quânticos , Técnicas Biossensoriais/métodos , Sistemas CRISPR-Cas , DNA , Técnicas Eletroquímicas/métodos , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Pontos Quânticos/química , Prata/química , Cobre/química
18.
Biosens Bioelectron ; 232: 115315, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37068419

RESUMO

In this work, a unique FeMoOv nanozyme-bipolar electrode (NM-BPE) electrochemiluminescence (ECL) biosensing and imaging platform was proposed for the first time to realize sensitive detection of target hydrogen peroxide (H2O2) and prostate specific antigen (PSA). Considering the advantage that the cathode and anode poles of the bipolar electrode (BPE) can be modified respectively, this work was carried out using anode equipped with ECL reagent bipyridine ruthenium (Ru(bpy)32+), and cathode equipped with the Fe-doped molybdenum oxide/Au nanoparticles (FeMoOv/AuNPs) with excellent peroxidase (POD) and catalase (CAT)-like activity. Because FeMoOv/AuNPs show efficient enzyme catalysis effect and can greatly promote the decomposition of H2O2, thus the electron transfer rate in the NM-BPE system would be much accelerated to enhance the ECL signal of Ru(bpy)32+. Based on this principle, this work not only realized sensitive detection of H2O2, but also ingeniously designed an sandwich immunosensor using FeMoOv/AuNPs as recognition probe to mediate the ECL response on the anode, achieving highly sensitive detection of PSA. Furthermore, a unique mobile phone ECL imaging system was developed for assay of PSA at different concentrations, which opened a new portable imaging sensing device for bioassays. This work was the first time to combine nanozymes with bipolar electrodes for ECL analysis and imaging, which not only broadened the applications of nanozymes, but also pioneered the new joint ECL research technique of bipolar electrode and ECL imaging in bioassays, showing great application prospect for multiple detection of proteins, nucleic acids and cancer cells.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Masculino , Antígeno Prostático Específico , Peróxido de Hidrogênio , Medições Luminescentes/métodos , Ouro , Técnicas Biossensoriais/métodos , Imunoensaio , Eletrodos , Técnicas Eletroquímicas/métodos
19.
Anal Chim Acta ; 1251: 340999, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-36925289

RESUMO

Developing a simple and easy-to-operate biosensor with tunable dynamic range would provide enormous opportunities to promote the diagnostic applications. Herein, an enzyme-responsive electrochemical DNA biosensor is developed by using only-one immobilization probe. The immobilization probe was designed with a two-loop hairpin-like structure that contained the mutually independent target recognition and enzyme (EcoRI restriction endonuclease) responsive domains. The target recognition was based on a toehold-mediated strand displacement reaction strategy. The toehold region was initially caged in the loop of the immobilization probe and showed a relatively low binding affinity with target, which was improved via EcoRI cleavage of immobilization probe to liberate the toehold region. The EcoRI cleavage operation for immobilization probe demonstrated the well regulation ability in detection performance. It showed a largely extended dynamic range, a significantly lowered detection limit and better discrimination ability toward the mismatched sequences whether in two buffers (with high or low salt concentrations) or in the serum system. The advantages also includes simplicity in probe design, and facile biosensor fabrication and operation. It thus opens a new avenue for the development of the modulated DNA biosensor and hold a great potential for the diagnostic applications and drug monitoring.


Assuntos
Técnicas Biossensoriais , DNA , Limite de Detecção , DNA/química , Técnicas Eletroquímicas
20.
Ann Rheum Dis ; 82(4): 533-545, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36543525

RESUMO

OBJECTIVE: The aim of this study was to identify the role of Piezo1-mediated mechanotransduction in entheseal pathological new bone formation and to explore the underlying molecular mechanism. METHODS: Spinal ligament tissues were collected from 14 patients with ankylosing spondylitis (AS) and 14 non-AS controls and bulk RNA sequencing was conducted. Collagen antibody-induced arthritis models were established to observe pathological new bone formation. Pharmacological inhibition and genetic ablation of Piezo1 was performed in animal models to identify the essential role of Piezo1. Entheseal osteo-chondral lineage cells were collected and in vitro cell culture system was established to study the role and underlying mechanism of Piezo1 in regulation of chondrogenesis, osteogenesis and its own expression. RESULTS: Piezo1 was aberrantly upregulated in ligaments and entheseal tissues from patients with AS and animal models. Pharmaceutical and genetic inhibition of Piezo1 attenuated while activation of Piezo1 promoted pathological new bone formation. Mechanistically, activation of CaMKII (Calcium/calmodulin dependent protein kinase II) signalling was found essential for Piezo1-mediated mechanotransduction. In addition, Piezo1 was upregulated by AS-associated inflammatory cytokines. CONCLUSION: Piezo1-mediated mechanotransduction promotes entheseal pathological new bone formation through CaMKII signalling in AS.


Assuntos
Canais Iônicos , Mecanotransdução Celular , Ossificação Heterotópica , Espondilite Anquilosante , Animais , Humanos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Osteogênese/genética , Espondilite Anquilosante/genética , Espondilite Anquilosante/metabolismo , Canais Iônicos/metabolismo
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