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1.
Schizophr Res ; 267: 519-527, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38704344

RESUMEN

BACKGROUND: Previous investigations have revealed substantial differences in neuroimaging characteristics between healthy controls (HCs) and individuals diagnosed with schizophrenia (SCZ). However, we are not entirely sure how brain activity links to symptoms in schizophrenia, and there is a need for reliable brain imaging markers for treatment prediction. METHODS: In this longitudinal study, we examined 56 individuals diagnosed with 56 SCZ and 51 HCs. The SCZ patients underwent a three-month course of antipsychotic treatment. We employed resting-state functional magnetic resonance imaging (fMRI) along with fractional Amplitude of Low Frequency Fluctuations (fALFF) and support vector regression (SVR) methods for data acquisition and subsequent analysis. RESULTS: In this study, we initially noted lower fALFF values in the right postcentral/precentral gyrus and left postcentral gyrus, coupled with higher fALFF values in the left hippocampus and right putamen in SCZ patients compared to the HCs at baseline. However, when comparing fALFF values in brain regions with abnormal baseline fALFF values for SCZ patients who completed the follow-up, no significant differences in fALFF values were observed after 3 months of treatment compared to baseline data. The fALFF values in the right postcentral/precentral gyrus and left postcentral gyrus, and the left postcentral gyrus were useful in predicting treatment effects. CONCLUSION: Our findings suggest that reduced fALFF values in the sensory-motor networks and increased fALFF values in the limbic system may constitute distinctive neurobiological features in SCZ patients. These findings may serve as potential neuroimaging markers for the prognosis of SCZ patients.


Asunto(s)
Antipsicóticos , Sistema Límbico , Imagen por Resonancia Magnética , Esquizofrenia , Humanos , Esquizofrenia/fisiopatología , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Masculino , Femenino , Adulto , Antipsicóticos/farmacología , Sistema Límbico/diagnóstico por imagen , Sistema Límbico/fisiopatología , Estudios Longitudinales , Adulto Joven , Resultado del Tratamiento , Evaluación de Resultado en la Atención de Salud , Persona de Mediana Edad , Máquina de Vectores de Soporte
2.
Brain Res ; 1838: 148977, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38705556

RESUMEN

OBJECTIVE: Previous research has suggested a connection between major depressive disorder (MDD) and certain comorbidities, including gastrointestinal issues, thyroid dysfunctions, and glycolipid metabolism abnormalities. However, the relationships between these factors and asymmetrical alterations in functional connectivity (FC) in adults with MDD remain unclear. METHOD: We conducted a study on a cohort of 42 MDD patients and 42 healthy controls (HCs). Participants underwent comprehensive clinical assessments, including evaluations of blood lipids and thyroid hormone levels, as well as resting-state functional magnetic resonance imaging (Rs-fMRI) scans. Data analysis involved correlation analysis to compute the parameter of asymmetry (PAS) for the entire brain's functional connectome. We then examined the interrelationships between abnormal PAS regions in the brain, thyroid hormone levels, and blood lipid levels. RESULTS: The third-generation ultra-sensitive thyroid stimulating hormone (TSH3UL) level was found to be significantly lower in MDD patients compared to HCs. The PAS score of the left inferior frontal gyrus (IFG) decreased, while the bilateral posterior cingulate cortex (Bi-PCC) PAS increased in MDD patients relative to HCs. Notably, the PAS score of the left IFG negatively correlated with both TSH and total cholesterol (CHOL) levels. However, these correlations lose significance after the Bonferroni correction. CONCLUSION: MDD patients demonstrated abnormal asymmetry in resting-state FC (Rs-FC) within the fronto-limbic system, which may be associated with CHOL and thyroid hormone levels.

3.
Small ; : e2310678, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38708801

RESUMEN

The quality requirements of graphene depend on the applications. Some have a high tolerance for graphene quality and even require some defects, while others require graphene as perfect as possible to achieve good performance. So far, synthesis of large-area graphene films by chemical vapor deposition of carbon precursors on metal substrates, especially on Cu, remains the main way to produce high-quality graphene, which has been significantly developed in the past 15 years. However, although many prototypes are demonstrated, their performance is still more or less far from the theoretical property limit of graphene. This review focuses on how to make super graphene, namely graphene with a perfect structure and free of contaminations. More specially, this study focuses on graphene synthesis on Cu substrates. Typical defects in graphene are first discussed together with the formation mechanisms and how they are characterized normally, followed with a brief review of graphene properties and the effects of defects. Then, the synthesis progress of super graphene from the aspects of substrate, grain size, wrinkles, contamination, adlayers, and point defects are reviewed. Graphene transfer is briefly discussed as well. Finally, the challenges to make super graphene are discussed and a strategy is proposed.

4.
J Pharm Biomed Anal ; 245: 116161, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38714135

RESUMEN

In this study, Fe3O4@ZnCr-layered double hydroxide/zeolitic imidazolate frameworks-8 (MLDH/ZIF-8) magnetically functionalized composites were synthesized by co-precipitation and in situ growth based on the advantages of LDHs and ZIF-8 using Fe3O4 nanoparticles as a magnetic substrate to obtain adsorbents with excellent performance. Moreover, the composite was used for the efficient enrichment of flavonoids in Chinese herbal medicines. The internal structures and surface properties were characterized by SEM, Fourier transform infrared spectroscopy, X-ray diffraction and so on. MLDH/ZIF-8 exhibited a large specific surface area and good paramagnetic properties. The MLDH/ZIF-8 magnetic composite was used as a magnetic solid-phase extraction (MSPE) adsorbent, and a MLDH/ZIF-8 MSPE-pressurized capillary electrochromatography coupling method was developed for the separation and detection of flavonoids (luteolin, kaempferol and apigenin) in a sample of the Chinese herb Ohwia caudata (Thunberg) H. Ohashi. The relevant parameters affecting the extraction efficiency were optimized to determine the ideal conditions for MSPE. 5 mg of adsorbent in sample solution at pH 6, vortex extraction for 5 min, elution with 1.5 mL of ethyl acetate for 15 min. The method showed good linearity in the concentration range of 3-50 µg mL-1 with correlation coefficients of 0.9934-0.9981, and displayed a relatively LODs of 0.07-0.09 µg mL-1. The spiked recoveries of all analytes ranged from 84.5% to 122.0% with RSDs (n=3) between 4.5% and 7.7%. This method is straightforward and efficient, with promising potential in the separation and analysis of active ingredients in various Chinese herbal medicines.


Asunto(s)
Medicamentos Herbarios Chinos , Flavonoides , Hidróxidos , Extracción en Fase Sólida , Flavonoides/aislamiento & purificación , Flavonoides/análisis , Flavonoides/química , Extracción en Fase Sólida/métodos , Hidróxidos/química , Medicamentos Herbarios Chinos/química , Adsorción , Nanopartículas de Magnetita/química , Estructuras Metalorgánicas/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos
5.
Heliyon ; 10(10): e31125, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38778939

RESUMEN

Background: The relationship between dietary vitamin B6 and stroke risk is controversial; thus, we analyzed their correlation using data from the National Health and Nutrition Examination Survey (NHANES). Method: Data from 2005 to 2018 were collected from the NHANES database. Two 24-h dietary recalls and a standard questionnaire were used to evaluate vitamin B6 intake and stroke prevalence. We used logistic regression models to estimate the association between dietary vitamin B6 intake and stroke risk and investigated the nonlinear relationship between them using a restricted cubic spline (RCS). Sensitivity analysis was conducted using propensity score matching (PSM). Results: Among 24,214 participants, 921 were patients diagnosed with stroke, while 23,293 were without stroke. The multivariate logistic regression model revealed that individuals in the highest quartile of vitamin B6 consumption had a significantly lower stroke risk than those in the lowest quartile under the fully adjusted model (OR: 0.48, 95 % CI: 0.35-0.66, P < 0.001). Subgroup analyses showed that dietary intake of vitamin B6 was a significant protective factor against stroke risk in different populations, with the most pronounced effect in the population engaging in moderate-intensity physical activity (OR: 0.34, 95%CI: 0.20-0.57). The RCS models revealed a non-linear L-shaped relationship (P for nonlinearity = 0.006) between stroke and dietary intake of vitamin B6. Conclusions: Our study shows that an increased intake of vitamin B6 could be an effective strategy in reducing the risk of stroke.

6.
Anal Methods ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38779841

RESUMEN

Biomolecules play vital roles in many biological processes and diseases, making their identification crucial. Herein, we present a colorimetric sensing method for detecting biomolecules like cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). This approach is based on a reaction system whereby colorless 3,3',5,5'-tetramethylbenzidine (TMB) undergoes catalytic oxidation to form blue-colored oxidized TMB (ox-TMB) in the presence of hydrogen peroxide (H2O2), utilizing the peroxidase and catalase-mimicking activities of metal-phenolic coordination frameworks (MPNs) of Cu-TA, Co-TA, and Fe-TA nanospheres. The Fe-TA nanospheres demonstrated superior activity, more active sites and enhanced electron transport. Under optimal conditions, the Fe-TA nanospheres were used for the detection of biomolecules. When present, biomolecules inhibit the reaction between TMB and H2O2, causing various colorimetric responses at low detection limits of 0.382, 0.776 and 0.750 µM for Cys, Hcy and GSH. Furthermore, it was successfully applied to real water samples with good recovery results. The developed sensor not only offers a rapid, portable, and user-friendly technique for multi-target analysis of biomolecules at low concentrations but also expands the potential uses of MPNs for other targets in the environmental field.

7.
Surg Innov ; : 15533506241255766, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38780068

RESUMEN

INTRODUCTION: Robotic surgery has transformed minimally invasive procedures, offering precision and efficiency. However, the ergonomic aspects of robotic consoles and their impact on surgeon health remain understudied. This review investigates the burden of ergonomics and muscle fatigue among robotic surgeons in China, comparing the findings to a multinational study. METHODOLOGY: A literature review identified themes related to physical discomfort in robotic surgery. A questionnaire was administered to Chinese robotic surgeons, yielding 40 responses. The study assessed demographic characteristics, surgeon experience, ergonomic practices, reported discomfort, and pain-relief mechanisms. RESULTS: The study revealed that most surgeons experienced shoulder and neck pain, with mixed opinions on whether robotic surgery was the primary cause. Stretching exercises were commonly used for pain relief. Surgeons believed that case volume and surgery duration contributed to discomfort. Comparisons with a multinational study suggested potential demographic and experience-related differences. CONCLUSION: While the study has limitations, including a small sample size and potential translation issues, it underscores the importance of addressing ergonomic concerns and providing proper training to robotic surgeons to ensure their well-being and longevity in the field. Further research with larger cohorts and platform-specific analyses is warranted.

8.
EBioMedicine ; 104: 105152, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38728838

RESUMEN

BACKGROUND: The tumour stroma is associated with unfavourable prognosis in diverse solid tumours, but its prognostic and predictive value in bladder cancer (BCa) is unclear. METHODS: In this multicentre, retrospective study, we included 830 patients with BCa from six independent cohorts. Differences in overall survival (OS) and cancer-specific survival (CSS) were investigated between high-tumour stroma ratio (TSR) and low-TSR groups. Multi-omics analyses, including RNA sequencing, immunohistochemistry, and single-cell RNA sequencing, were performed to study stroma-immune interactions. TSR prediction models were developed based on pelvic CT scans, and the best performing model was selected based on receiver operator characteristic analysis. FINDINGS: Compared to low-TSR tumours, high-TSR tumours were significantly associated with worse OS (HR = 1.193, 95% CI: 1.046-1.361, P = 0.008) and CSS (HR = 1.337, 95% CI: 1.139-1.569, P < 0.001), and lower rate of pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). High-TSR tumours exhibited higher infiltration of immunosuppressive cells, including Tregs and tumour-associated neutrophils, while low-TSR tumours exhibited higher infiltration of immune-activating cells such as CD8+ Teff and XCR1+ dendritic cells. The TSR prediction model was developed by combining the intra-tumour and tumour base radiomics features, and showed good performance to predict high-TSR, as indicted by area under the curve of 0.871 (95% CI: 0.821-0.921), 0.821 (95% CI: 0.731-0.911), and 0.801 (95% CI: 0.737-0.865) in the training, internal validation, and external validation cohorts, respectively. In patients with low predicted TSR, 92.3% (12/13) achieved pCR, while only 35.3% (6/17) of patients with high predicted TSR achieved pCR. INTERPRETATION: The tumour stroma was found to be significantly associated with clinical outcomes in patients with BCa as a result of tumour stroma-immune interactions. The radiomics prediction model provided non-invasive evaluation of TSR and was able to predict pCR in patients receiving NAC for BCa. FUNDING: This work was supported by National Natural Science Foundation of China (Grant No. 82373254 and 81961128027), Guangdong Provincial Natural Science Foundation (Grant No. 2023A1515010258), Science and Technology Planning Project of Guangdong Province (Grant No. 2023B1212060013). Science and Technology Program of Guangzhou (SL2022A04J01754), Sun Yat-Sen Memorial Hospital Clinical Research 5010 Program (Grant No. SYS-5010Z-202401).

9.
Minerva Urol Nephrol ; 76(2): 241-246, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38742557

RESUMEN

BACKGROUND: To evaluate the feasibility and safety of dual-console telesurgery with the new KangDuo system in an animal experiment and clinical study. METHODS: Six canine models were performed radical prostatectomy with dual-console KanDuo surgical robot-1500 (KD-SR-1500-RARP). The perioperative outcomes, physical and mental workload of the surgeon were collected. Physical workload was evaluated with surface electromyography. Mental workload was evaluated with NASA-TLX. After conducting animal experiments to verify safety of dual-console KD-SR-1500-RARP, we conducted the clinical trial using 5G and wired networks. RESULTS: In the animal experiment, all surgeries were performed successfully. The operative time was 80.2±32.1 min. The docking time was 2.4±0.5 min. The console time was 49.7±25.3 min. There were no perioperative complications or equipment related adverse events. All dogs can micturate after catheter removal at one week postoperatively. The mental workload was at a low level (a scale ranging from 0 to 60), which scored 15.7±6.9. Among the eight recorded muscles, the fatigue degree of the right radial flexor and left biceps was the highest two (iEMG, resection, 299.8±344 uV, 109.9±16.9 uV; suture, 849.4±1252.5 uV, 423.1±621.3 uV, respectively). In the clinical study, the console time was 136 min. The mean latency time was ≤200 ms. The data pocket loss was <1%. The operation was successfully completed without malfunctions occurring throughout the entire process. CONCLUSIONS: Dual-console telesurgery with the KD-SR-1500 system was shown to be feasible and safe in radical prostatectomy using 5G and wired networks.


Asunto(s)
Estudios de Factibilidad , Prostatectomía , Procedimientos Quirúrgicos Robotizados , Animales , Perros , Procedimientos Quirúrgicos Robotizados/métodos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Masculino , Prostatectomía/métodos , Prostatectomía/efectos adversos , Humanos , Persona de Mediana Edad , Diseño de Equipo , Tempo Operativo , Anciano , Electromiografía , Telemedicina/métodos
10.
Adv Colloid Interface Sci ; 328: 103179, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38754212

RESUMEN

Membrane technology has emerged as a crucial method for obtaining clean water from unconventional sources in the face of water scarcity. It finds wide applications in wastewater treatment, advanced treatment, and desalination of seawater and brackish water. However, membrane fouling poses a huge challenge that limits the development of membrane-based water treatment technologies. Characterizing the dynamics of membrane fouling is crucial for understanding its development, mechanisms, and effective mitigation. Instrumental techniques that enable in situ or real-time characterization of the dynamics of membrane fouling provide insights into the temporal and spatial evolution of fouling, which play a crucial role in understanding the fouling mechanism and the formulation of membrane control strategies. This review consolidates existing knowledge about the principal advanced instrumental analysis technologies employed to characterize the dynamics of membrane fouling, in terms of membrane structure, morphology, and intermolecular forces. Working principles, applications, and limitations of each technique are discussed, enabling researchers to select appropriate methods for their specific studies. Furthermore, prospects for the future development of dynamic characterization techniques for membrane fouling are discussed, underscoring the need for continued research and innovation in this field to overcome the challenges posed by membrane fouling.

11.
Chemistry ; : e202400803, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38752562

RESUMEN

To meet the demand for higher energy density in lithium-ion batteries and expand their application range, coupling lithium metal anodes with high-voltage cathodes is an ideal solution. However, the compatibility between lithium metal batteries and electrolytes affects their applicability. In this study, proposes a locally concentrated electrolyte based on ethyl acetate (EA) as the solvent, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as the lithium salt, and lithium difluorooxoborate (LiDFOB) as a sacrificial agent to enhance the low-temperature and high-voltage endurance of Li//Lithium cobalt oxide (LCO) batteries. The Li//LCO battery can operate within the voltage range of 3 to 4.5 V, with an initial discharge specific capacity of 174.5 mAh g-1 at 20 oC. At -40 oC, after 200 cycles, the capacity retention rate is 87.7%. It can operate under extreme conditions of -70 oC, with a discharge specific capacity of 112.6 mAh g-1. Additionally, LCO//HC batteries using this electrolyte demonstrate excellent performance. Present work provides a new perspective for the optimization of electrolytes for low-temperature lithium-ion batteries.

12.
Cell Rep ; 43(5): 114180, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38733581

RESUMEN

Macrophage activation is a hallmark of atherosclerosis, accompanied by a switch in core metabolism from oxidative phosphorylation to glycolysis. The crosstalk between metabolic rewiring and histone modifications in macrophages is worthy of further investigation. Here, we find that lactate efflux-associated monocarboxylate transporter 4 (MCT4)-mediated histone lactylation is closely related to atherosclerosis. Histone H3 lysine 18 lactylation dependent on MCT4 deficiency activated the transcription of anti-inflammatory genes and tricarboxylic acid cycle genes, resulting in the initiation of local repair and homeostasis. Strikingly, histone lactylation is characteristically involved in the stage-specific local repair process during M1 to M2 transformation, whereas histone methylation and acetylation are not. Gene manipulation and protein hydrolysis-targeted chimerism technology are used to confirm that MCT4 deficiency favors ameliorating atherosclerosis. Therefore, our study shows that macrophage MCT4 deficiency, which links metabolic rewiring and histone modifications, plays a key role in training macrophages to become repair and homeostasis phenotypes.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124339, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38696995

RESUMEN

The FDA (Food and Drug Administration, (USA)) lists ZnO as a material that is widely acknowledged to be safe. ZnO NPs with a range of tiny particle sizes were made using the precipitation process. ZnO nanoparticles' surface is embellished with a tripodal sensor containing naphthol units. The assembly with the same receptor decorated on ZnO NPs is contrasted with the cation detection capabilities of the purified tripodal receptor. The UV-visible spectrophotometric analysis was conducted to study the state transitions of the receptor and the decorated ZnO receptor. A positive selectivity to Al3+ cations is determined by the fluorescence study under ideal circumstances. The particle size and surface morphologies are determined by DLS and SEM analysis for the same receptor - TP1 and embellished with a tripodal receptor TP2. Using a fluorescence switch-on Photoinduced Electron Transfer (PET) mechanism, the receptor coated on ZnO detects the presence of Al3+ ions with specificity. The binding constant value was determined using the B-H plot equation. Binding stoichiometry for [TP1-Al3+, TP2-Al3+] showed a 1:1 ratio. The fluorescence switches ON-OFF process of the ZnO surface adorned - TP2 with Tripodal receptor- TP1 was used to create molecular logic gates, which can function as a module for sensors and molecular switches. The addition of Na2EDTA in the solution of the [TP1; TP2 - Al3+] complex resulted in a noticeable reduction in the emission of fluorescence. This finding offers compelling support for the reversibility of the chemosensor. To enable the practical application of this sensor, we have developed a cassette containing receptors TP1 and TP2. Successfully, it can detect Al3+ metal ions. We performed a comprehensive assessment of the dependability and appropriateness of our approach in measuring the concentration of Al3+ ions in wastewater produced by important industrial procedures.

15.
Cancer Invest ; : 1-19, 2024 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-38644691

RESUMEN

This study aims to develop a prognostic signature based on m6A-related lncRNAs for clear cell renal cell carcinoma (ccRCC). Differential expression analysis and Pearson correlation analysis were used to identify m6A-related lncRNAs associated with patient outcomes in The Cancer Genome Atlas (TCGA) database. Our approach led to the development of an m6A-related lncRNA risk score (MRLrisk), formulated using six identified lncRNAs: NFE4, AL008729.2, AL139123.1, LINC02154, AC124854.1 and ARHGAP31-AS1. Higher MRLrisk was identified as a risk factor for patients' prognosis in ccRCC. Furthermore, an MRLrisk-based nomogram was developed and demonstrated as a reliable tool for prognosis prediction in ccRCC. Enrichment analysis and tumor mutation signature studies were conducted to investigate MRLrisk-related biological phenotypes. The tumor immune dysfunction and exclusion (TIDE) score was employed to infer patients' response to immunotherapy, indicating a negative correlation between high MRLrisk and immunotherapy response. Our focus then shifted to LINC02154 for deeper exploration. We assessed LINC02154 expression in 28 ccRCC/normal tissue pairs and 3 ccRCC cell lines through quantitative real-time polymerase chain reaction (qRT-PCR). Functional experiments, including EdU incorporation, flow cytometry and transwell assays, were performed to assess the role of LINC02154 in ccRCC cell functions, discovering that its downregulation hinders cancer cell proliferation and migration. Furthermore, the influence of LINC02154 on ccRCC cells' sensitivity to Sunitinib was explored using CCK-8 assays, demonstrating that decreased LINC02154 expression increases Sunitinib sensitivity. In summary, this study successfully developed an MRLrisk model with significant prognostic value for ccRCC and established LINC02154 as a critical biomarker and prospective therapeutic target in ccRCC management.

16.
J Endourol ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38623792

RESUMEN

PURPOSE: To investigate the feasibility, safety, and efficacy of the KangDuo Surgical Robot-01 (KD-SR-01) system for robot-assisted radical nephroureterectomy (UTUC). MATERIALS AND METHODS: This prospective, single-center, single-arm clinical study of patients with UTUC was conducted from August 2022 to July 2023 using the KD-SR-01 system. The perioperative and follow-up data were prospectively recorded. The National Aeronautics and Space Administration Task Load Index was calculated to present ergonomics. The technique was described in detail. RESULTS: A total of 13 patients underwent RARNU. None of the cases conversed to laparoscopic surgery or open surgery. The median docking time and console time were 524 (range, 139-963) seconds and 102.2 (range, 55.3-249.3) minutes, respectively. The median estimated blood loss was 40 (range, 10-100) ml. None of the patients required intraoperative blood transfusion. The median postoperative hospital stay was 4 (range, 2-7) days. Intraoperative or postoperative complications (Clavien-Dindo grade I) occurred in 9 patients. The surgeon Task Load Index global score achieved 1.05±1.86. Three patients received the single-docking technique, demonstrating similar perioperative results compared to patients with re-docking. CONCLUSIONS: The KD-SR-01 system was feasible, safe, and effective for robot-assisted radical nephroureterectomy.

17.
Sensors (Basel) ; 24(7)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38610537

RESUMEN

Conventional spherical nucleic acid enzymes (SNAzymes), made with gold nanoparticle (AuNPs) cores and DNA shells, are widely applied in bioanalysis owing to their excellent physicochemical properties. Albeit important, the crowded catalytic units (such as G-quadruplex, G4) on the limited AuNPs surface inevitably influence their catalytic activities. Herin, a hybridization chain reaction (HCR) is employed as a means to expand the quantity and spaces of G4 enzymes for their catalytic ability enhancement. Through systematic investigations, we found that when an incomplete G4 sequence was linked at the sticky ends of the hairpins with split modes (3:1 and 2:2), this would significantly decrease the HCR hybridization capability due to increased steric hindrance. In contrast, the HCR hybridization capability was remarkably enhanced after the complete G4 sequence was directly modified at the non-sticky end of the hairpins, ascribed to the steric hindrance avoided. Accordingly, the improved SNAzymes using HCR were applied for the determination of AFB1 in food samples as a proof-of-concept, which exhibited outstanding performance (detection limit, 0.08 ng/mL). Importantly, our strategy provided a new insight for the catalytic activity improvement in SNAzymes using G4 as a signaling molecule.


Asunto(s)
Nanopartículas del Metal , Ácidos Nucleicos , Aflatoxina B1 , Oro , Hibridación de Ácido Nucleico
18.
Biochem Biophys Res Commun ; 715: 149979, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38678779

RESUMEN

Endothelial dysfunction is an initiating factor in atherosclerosis. Endothelial cells (ECs) are constantly subject to blood flow shear stress, and atherosclerotic plaques tend to occur in aortic bends or bifurcations impaired by low oscillatory shear stress (OSS). However, the mechanism that how OSS affects the initiation and progression of atherosclerosis remains to be explored. Here, we first reported that OSS can promote endothelial dysfunction and atherogenesis in vivo and in vitro by activating STING pathway. Mechanistically, at atherosclerosis-prone areas, OSS caused mitochondria damage in ECs, leading to the leakage of mitochondrial DNA (mtDNA) into the cytoplasm. The cytoplasmic mtDNA was recognized by cGAS to produce cGAMP, activating the STING pathway and leading to endothelial senescence, which resulted in endothelial dysfunction and atherosclerosis. We found that STING was activated in plaques of atherosclerotic patients and in aortic arch ECs of high-fat diet (HFD)-fed ApoeKO mice, as well as in ECs exposed to OSS. STING-specific deficiency in ECs attenuates endothelial senescence and resulted in a significant reduction in aortic arch plaque area in HFD-fed ApoeKO mice. Consistently, specific deficiency or pharmacological inhibition of STING attenuated OSS-induced senescence and endothelial dysfunction. Pharmacological depletion of mtDNA ameliorated OSS-induced senescence and endothelial dysfunction. Taken together, our study linked hemodynamics and endothelial senescence, and revealed a novel mechanism by which OSS leads to endothelial dysfunction. Our study provided new insights into the development of therapeutic strategies for endothelial senescence and atherosclerosis.


Asunto(s)
Aterosclerosis , Senescencia Celular , ADN Mitocondrial , Células Endoteliales , Proteínas de la Membrana , Ratones Endogámicos C57BL , Estrés Mecánico , Aterosclerosis/metabolismo , Aterosclerosis/patología , Aterosclerosis/genética , Animales , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Humanos , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Ratones , Células Endoteliales/metabolismo , Células Endoteliales/patología , Masculino , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Mitocondrias/metabolismo , Mitocondrias/patología , Dieta Alta en Grasa , Células Cultivadas
20.
Magn Reson Imaging ; 110: 86-95, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38631533

RESUMEN

Segmentation of cerebral vasculature on MR vascular images is of great significance for clinical application and research. However, the existing cerebrovascular segmentation approaches are limited due to insufficient image contrast and complicated algorithms. This study aims to explore the potential of the emerging four-dimensional arterial spin labeling magnetic resonance angiography (4D ASL-MRA) technique for fast and accurate cerebrovascular segmentation with a simple machine-learning approach. Nine temporal features were extracted from the intensity-time signal of each voxel, and eight spatial features from the neighboring voxels. Then, the unsupervised outlier detection algorithm, i.e. Isolation Forest, is used for segmentation of the vascular voxels based on the extracted features. The total length of the centerlines of the intracranial arterial vasculature, the dice similarity coefficient (DSC), and the average Hausdorff Distance (AVGHD) on the cross-sections of small- to large-sized vessels were calculated to evaluate the performance of the segmentation approach on 4D ASL-MRA of 18 subjects. Experiments show that the temporal information on 4D ASL-MRA can largely improve the segmentation performance. In addition, the proposed segmentation approach outperforms the traditional methods that were performed on the 3D image (i.e. the temporal average intensity projection of 4D ASL-MRA) and the previously proposed frame-wise approach. In conclusion, this study demonstrates that accurate and robust segmentation of cerebral vasculature is achievable on 4D ASL-MRA by using a simple machine-learning approach with appropriate features.


Asunto(s)
Algoritmos , Imagenología Tridimensional , Aprendizaje Automático , Angiografía por Resonancia Magnética , Marcadores de Spin , Humanos , Angiografía por Resonancia Magnética/métodos , Imagenología Tridimensional/métodos , Masculino , Femenino , Adulto , Arterias Cerebrales/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Circulación Cerebrovascular , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea
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