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1.
Talanta ; 279: 126630, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39098242

RESUMEN

Laccase is well-known for its eco-friendly applications in environmental remediation and biotechnology, but its high cost and low stability have limited its practical use. Therefore, there is an urgent need to develop efficient laccase mimetics. In this study, a novel laccase-mimicking nanozyme (MBI-Cu) was successfully synthesized using 2-methylbenzimidazole (MBI) coordinated with Cu2+ by mimicking the copper active site and electron transfer pathway of natural laccase. MBI-Cu nanozyme exhibited excellent catalytic activity and higher stability than laccase, and was utilized to oxidize a series of phenolic compounds. Environmental pollutant aminophenol isomers were found to display different color in solution when catalytically oxidized by MBI-Cu, which provided a simple and feasible method to identify them by the naked eye. Based on the distinct absorption spectra of the oxidized aminophenol isomers, a colorimetric method for quantitatively detecting o-AP, m-AP, and p-AP was established, with detection limits of 0.06 µM, 0.27 µM, and 0.18 µM, respectively. Furthermore, by integrating MBI-Cu-based cotton pad colorimetric strips with smartphone and utilizing color recognition software to identify and analyze the RGB values of the images, a portable colorimetric sensing platform was designed for rapid detection of aminophenol isomers without the need for any analytical instrument. This work provides an effective reference for the design of laccase nanozymes and holds significant potential for applications in the field of environmental pollutant monitoring.

2.
Ren Fail ; 46(2): 2391069, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39143819

RESUMEN

OBJECTIVE: High serum levels of B-cell activation factor (BAFF) and a proliferation-inducing ligand (APRIL) have been observed in patients with idiopathic membranous nephropathy (iMN); however, their relationships with disease severity and progression remain unclear. METHODS: Patients with iMN diagnosed via renal biopsy were enrolled in this study. The concentrations of BAFF and APRIL were determined using ELISA kits. Proteinuria remission, including complete remission (CR) and partial remission (PR), and renal function deterioration were defined as clinical events. The Cox proportional hazards method was used to analyze the relationship between cytokine levels and disease progression. RESULTS: Seventy iMN patients were enrolled in this study, with a median follow-up time of 24 months (range 6-72 months). The serum levels of BAFF and APRIL were higher in iMN patients than in healthy controls but lower than those in minimal change disease (MCD) patients. The serum BAFF level was positively correlated with the serum APRIL level, serum anti-phospholipase A2 receptor (anti-PLA2R) antibody level, and 24-h proteinuria and negatively correlated with the serum albumin (ALB) level. However, no significant correlation was observed between the serum APRIL level and clinical parameters. According to the multivariate Cox proportional hazards regression model adjusted for sex, age, systolic blood pressure (SBP), estimated glomerular filtration rate (eGFR), immunosuppressive agent use, 24-h proteinuria, APRIL level, and anti-PLA2R antibody, only the serum BAFF level was identified as an independent predictor of PR (HR, 0.613; 95% CI, 0.405-0.927; p = 0.021) and CR of proteinuria (HR, 0.362; 95% CI, 0.202-0.648; p < 0.001). CONCLUSIONS: A high serum BAFF level is associated with severe clinical manifestations and poor disease progression in patients with iMN.


Asunto(s)
Factor Activador de Células B , Progresión de la Enfermedad , Glomerulonefritis Membranosa , Proteinuria , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral , Humanos , Glomerulonefritis Membranosa/sangre , Glomerulonefritis Membranosa/diagnóstico , Factor Activador de Células B/sangre , Masculino , Femenino , Persona de Mediana Edad , Adulto , Pronóstico , Miembro 13 de la Superfamilia de Ligandos de Factores de Necrosis Tumoral/sangre , Proteinuria/sangre , Proteinuria/etiología , Modelos de Riesgos Proporcionales , Receptores de Fosfolipasa A2/inmunología , Receptores de Fosfolipasa A2/sangre , Estudios de Casos y Controles , Anciano , Tasa de Filtración Glomerular , Riñón/fisiopatología , Riñón/patología
3.
J Bone Oncol ; 47: 100618, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39050186

RESUMEN

Osteosarcoma is the most common primary malignant bone tumor in adolescents. While treatments for osteosarcoma have improved, the overall survival has not changed for three decades, and thus, new targets for therapeutic development are needed. Recently, glucocorticoids have been reported to have antitumor effects. Mometasone furoate (MF), a synthetic glucocorticoid, is of great value in clinical application, but there are few reports on its antitumor effect. Here, we verified the effect of MF on osteosarcoma in vitro and in vivo. In vitro, cell proliferation, cell cycle progression, apoptosis and cell metastasis were detected using Cell Counting Kit-8 (CCK-8), colony formation, flow cytometry, wound-healing and transwell assays, respectively. In vivo, we generated a xenograft mouse model. To examine the potential role of the AMPK pathway, an AMPK-specific inhibitor (dorsomorphin) was used. The expression levels of factors related to the cell cycle, apoptosis and activation of the AMPK/mTOR pathway were assessed by immunohistochemistry and Western blotting. MF inhibited proliferation and metastasis and induced S phase arrest and apoptosis in osteosarcoma cells in a dose-dependent manner. In vivo, MF effectively inhibited osteosarcoma cell growth and pulmonary metastasis; however, it had no negative effect on the internal organs. Additionally, MF could activate the AMPK/mTOR pathway in osteosarcoma. Dorsomorphin significantly attenuated MF-induced antitumor activities. In summary, MF can inhibit osteosarcoma proliferation and metastasis and promote osteosarcoma cell apoptosis through the AMPK/mTOR signaling pathway in vitro and in vivo, which can provide a new rationale for subsequent academic and clinical research on osteosarcoma treatment.

4.
Talanta ; 279: 126603, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39053355

RESUMEN

Enzyme catalytic cascade reactions based on peroxidase nanozymes and natural enzymes have aroused extensive attention in analytical fields. However, a majority of peroxidase nanozymes perform well only in acidic environments, resulting in their optimal pH mismatch with a neutral pH of natural enzymes, further restricting their application in biochemical sensing. Herein, Mn-doped CeO2 (Mn/CeO2) performing enhanced peroxidase-like activity at neutral conditions was prepared via a facile and feasible strategy. An effective enzyme cascade catalysis system via integrating glucose oxidase (GOx) with Mn/CeO2 was developed for one-pot detection of glucose in serum at neutral conditions. Using one-pot multistep catalytic reactions, this work provided a detection platform that allows for faster detection and easier operations than traditional methods. Under optimized conditions, our assay performed a sensitive detection of glucose ranging from 2.0 µΜ to 300 µΜ and a low detection limit of 0.279 µΜ. Notably, favorable analytical outcomes for glucose detection in serum samples were obtained, exhibiting potential applications in clinical diagnosis.

5.
Curr Med Sci ; 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38967890

RESUMEN

OBJECTIVE: To examine the clinical phenotype and genetic deficiencies present in Chinese aniridia families with PAX6 haplotype deficiency. METHODS: A comprehensive questionnaire and ophthalmological assessments were administered to both affected patients and unaffected relatives. The clinical feature analysis included the evaluation of visual acuity, intraocular pressure, slit-lamp anterior segment examination, fundus photography, and spectral domain optical coherence tomography. To identify the mutation responsible for aniridia, targeted next-generation sequencing was used as a beneficial technique. RESULTS: A total of 4 mutations were identified, consisting of two novel frameshift mutations (c.314delA, p.K105Sfs*33 and c.838_845dup AACACACC, p.S283Tfs*85), along with two recurring nonsense mutations (c.307C>T, p.R103X and c.619A>T, p.K207*). Complete iris absence, macular foveal hypoplasia, and nystagmus were consistent in these PAX6 haplotype-deficient Chinese aniridia families, while corneal lesions, cataracts, and glaucoma exhibited heterogeneity both among the families and within the same family. CONCLUSION: In our study, two novel PAX6 mutations associated with aniridia were identified in Chinese families, which expanded the phenotypic and genotypic spectrum of PAX6 mutations. We also analyzed the clinical characteristics of PAX6 haplotype deficiency in Chinese aniridia families.

6.
Hepatol Int ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954360

RESUMEN

BACKGROUND: The management of severe immune-related hepatotoxicity (irH) needs to be further optimized. This study aims to analyze the clinical characteristics of severe irH; improve the therapeutic strategy, especially salvage treatment in steroid-refractory irH; and determine the safety of immune checkpoint inhibitor (ICPi)-rechallenge. METHODS: This multicenter retrospective study included patients who developed severe irH and those without irH after immunotherapy between May 2019 and June 2023. Propensity score matching was used to match these two cohorts with similar baseline characteristics. RESULTS: Among 5,326 patients receiving ICPis, 51 patients developed severe irH. irH occurred after a median duration of 36 days and a median of two doses after the first ICPi administration. Patients receiving PD-L1 inhibitors faced a lower risk of developing severe irH. A higher dose of glucocorticoids (GCS) was administered to grade 4 irH than grade 3 irH. For steroid-sensitive patients, grade 4 irH individuals received a higher dosage of GCS than those with grade 3 irH, with no difference in time to resolution. Meanwhile, a significantly higher dose of GCS plus immunosuppression was needed in the steroid-refractory group. Liver biopsy of the steroid-refractory patients exhibited heterogeneous histological features. Twelve patients were retreated with ICPi. No irH reoccurred after a median follow-up of 9.3 months. CONCLUSION: irH requires multidimensional evaluation. PD-L1 inhibitors correlated with a lower risk of severe irH. Grade 4 irH demands a higher dose of GCS than recommended. Pathology may guide the salvage treatment for steroid-refractory irH. ICPi rechallenge in severe irH is feasible and safe.

7.
Adv Radiat Oncol ; 9(8): 101526, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39026611

RESUMEN

Purpose: To assess the clinical benefits of surface-guided radiation therapy (SGRT) in terms of setup error, positioning time, and clinical target volume-to-planning target volume (CTV-PTV) margin in extremity soft tissue sarcoma (STS). Methods and Materials: Fifty consecutive patients treated with radiation therapy were selected retrospectively. Treatment setup was performed with either laser-based imaging only (control group), or with laser-based and daily optical surface-based imaging (SGRT group). Pretreatment cone beam computed tomography images were acquired daily for the first 3 to 5 fractions and weekly thereafter, with the frequency adjusted as necessary. Translational and rotational errors were collected. CTV-PTV margin was calculated using the formula, 2.5Σ + 0.7σ. Results: Each group consisted of 10 and 15 upper and lower limb STSs, respectively. For patients with upper limb sarcomas, the translation errors were 1.64 ± 1.34 mm, 1.10 ± 1.50 mm, and 1.24 ± 1.45 mm in the SGRT group, and 1.48 ± 3.16 mm, 2.84 ± 2.85 mm, and 3.14 ± 3.29 mm in control group in the left-right, supero-inferior, and antero-posterior directions, respectively. Correspondingly, for patients with lower limb sarcomas, the translation errors were 1.21 ± 1.65 mm, 1.39 ± 1.71 mm, and 1.48 ± 2.10 mm in the SGRT group, and 1.81 ± 2.60 mm, 2.93 ± 3.28 mm, and 3.53 ± 3.75 mm in control group, respectively. The calculated CTV-PTV margins of the SGRT group and control group were 5.0, 3.8, 4.1 versus 5.9, 9.1, 10.1 mm for upper limb sarcomas; and 4.2, 4.7, 5.2 mm versus 6.3, 9.6, and 11.4 mm for lower limb sarcomas in the left-right, supero-inferior, and antero-posterior directions, respectively. Conclusions: Daily optical surface guidance can effectively improve the setup accuracy of extremity STS patients, and safely reduce the required CTV-PTV margins.

8.
Int J Ophthalmol ; 17(7): 1205-1216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39026915

RESUMEN

AIM: To explore the effect of silent information regulator factor 2-related enzyme 1 (SIRT1) on modulating apoptosis of human lens epithelial cells (HLECs) and alleviating lens opacification of rats through suppressing endoplasmic reticulum (ER) stress. METHODS: HLECs (SRA01/04) were treated with varying concentrations of tunicamycin (TM) for 24h, and the expression of SIRT1 and C/EBP homologous protein (CHOP) was assessed using real-time quantitative polymerase chain reaction (RT-PCR), Western blotting, and immunofluorescence. Cell morphology and proliferation was evaluated using an inverted microscope and cell counting kit-8 (CCK-8) assay, respectively. In the SRA01/04 cell apoptosis model, which underwent siRNA transfection for SIRT1 knockdown and SRT1720 treatment for its activation, the expression levels of SIRT1, CHOP, glucose regulated protein 78 (GRP78), and activating transcription factor 4 (ATF4) were examined. The potential reversal of SIRT1 knockdown effects by 4-phenyl butyric acid (4-PBA; an ER stress inhibitor) was investigated. In vivo, age-related cataract (ARC) rat models were induced by sodium selenite injection, and the protective role of SIRT1, activated by SRT1720 intraperitoneal injections, was evaluated through morphology observation, hematoxylin and eosin (H&E) staining, Western blotting, and RT-PCR. RESULTS: SIRT1 expression was downregulated in TM-induced SRA01/04 cells. Besides, in SRA01/04 cells, both cell apoptosis and CHOP expression increased with the rising doses of TM. ER stress was stimulated by TM, as evidenced by the increased GRP78 and ATF4 in the SRA01/04 cell apoptosis model. Inhibition of SIRT1 by siRNA knockdown increased ER stress activation, whereas SRT1720 treatment had opposite results. 4-PBA partly reverse the adverse effect of SIRT1 knockdown on apoptosis. In vivo, SRT1720 attenuated the lens opacification and weakened the ER stress activation in ARC rat models. CONCLUSION: SIRT1 plays a protective role against TM-induced apoptosis in HLECs and slows the progression of cataract in rats by inhibiting ER stress. These findings suggest a novel strategy for cataract treatment focused on targeting ER stress, highlighting the therapeutic potential of SIRT1 modulation in ARC development.

9.
Angew Chem Int Ed Engl ; : e202410397, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896110

RESUMEN

The valorization of native lignin to functionalized aromatic compounds under visible light is appealing yet challenging. In this communication, colloidal mercaptoalkanoic acid capped ultrathin ZnIn2S4 (ZIS) microbelts was successfully fabricated, which was used as a superior catalyst for depolymerization of native lignin in birch woodmeal under visible light, with an optimum yield of 28.8 wt % to functionalized aromatic monomers achieved in 8 h. The capped mercaptoalkanoic acid not only enables a solvent modulated reversible interchange of ZIS between the colloidal state for efficient reaction and the aggregated state for facile separation, but also serves as a precursor for light initiated generation of reactive thiyl radical for highly selective cleavage of ß-O-4 bond in native lignin. This work provides a green and efficient strategy for the depolymerization of native lignin to functionalized aromatic monomers under mild conditions, which involves a new mechanism for the cleavage of ß-O-4 bonds in native lignin. The capability of cleavage of ß-O-4 bonds in native lignin by photogenerated thiyl radicals also demonstrates the great potential of using photogenerated thiyl radicals in organics transformations.

10.
Gene ; 927: 148726, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38909969

RESUMEN

Congenital cataract is one of the leading causes of vision loss in children, and a large proportion of cases are related to genetics. In a Chinese family, we reported a new missense mutation in CRYBA2 (c.223T>C: p.Tyr75His), which can cause autosomal dominant congenital bilateral cataract. We collected blood samples from family members (mother and two sons) and extracted DNA. Through whole-exome sequencing, we discovered a novel unreported mutation. According to relevant ACMG guidelines, this mutation was determined to be a variant of unknown clinical significance. This article further expands the site information on the CRYBA2 mutations.


Asunto(s)
Catarata , Mutación Missense , Cadena A de beta-Cristalina , Femenino , Humanos , Masculino , Pueblo Asiatico/genética , Cadena A de beta-Cristalina/genética , Catarata/genética , Catarata/congénito , Secuenciación del Exoma/métodos
11.
Adv Sci (Weinh) ; 11(30): e2402531, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38864341

RESUMEN

Allostery is a fundamental way to regulate the function of biomolecules playing crucial roles in cell metabolism and proliferation and is deemed the second secret of life. Given the limited understanding of the structure of natural allosteric molecules, the development of artificial allosteric molecules brings a huge opportunity to transform the allosteric mechanism into practical applications. In this study, the concept of bionics is introduced into the design of artificial allosteric molecules and an allosteric DNA switch with an activity site and an allosteric site based on two aptamers for selective inhibition of thrombin activity. Compared with the single aptamer, the allosteric switch possesses a significantly enhanced inhibition ability, which can be precisely regulated by converting the switch states. Moreover, the dynamic allosteric switch is further subjected to the control of the DNA threshold circuit for realizing automatic concentration determination and activity inhibition of thrombin. These compelling results confirm that this allosteric switch equipped with self-sensing and information-processing modules puts a new slant on the research of allosteric mechanisms and further application of allosteric tactics in chemical and biomedical fields.


Asunto(s)
Aptámeros de Nucleótidos , Trombina , Aptámeros de Nucleótidos/química , Aptámeros de Nucleótidos/farmacología , Aptámeros de Nucleótidos/metabolismo , Regulación Alostérica , Trombina/metabolismo , Trombina/química , ADN/metabolismo , ADN/química , Sitio Alostérico , Humanos
12.
Opt Lett ; 49(11): 3082-3085, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824333

RESUMEN

In this Letter, we experimentally investigate a non-line-of-sight (NLOS) optical wireless communication (OWC) system that utilizes wavefront shaping techniques to realize simultaneous data transmission for multiple users. Wavefront shaping techniques are employed to address the issue of low intensity of diffusely reflected light at the receiver in NLOS scenarios for indoor high-speed access. To achieve communication path planning and tracing for two different users in free-space optical communication, the pixels of the spatial light modulator (SLM) are divided into two halves to separately manipulate the wavefront of two independent data carriers centered at different wavelengths. The maximum received optical power can be effectively improved by more than 15 dB with the wavefront shaping technique. To avoid power enhancement of non-target wavelength, the wavelength difference of two different users is experimentally studied. The difference in power enhancement ratio (DPER) is increased with the wavelength difference, and 14.95 dB DPER is obtained with a 10 nm wavelength difference. Under the aforementioned wavelength planning strategy, successful transmission and reception of 2 × 160 Gbit/s 16-QAM signals for two users with coherent detection is achieved using wavelengths of 1550 and 1560 nm in an indoor access scenario.

13.
PLoS One ; 19(6): e0305926, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38913606

RESUMEN

OBJECTIVE: This study aimed to evaluate the effects of trilobatin (TLB) on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice and further explore the underlying mechanisms from the perspectives of signaling pathway and gut microbiota. METHODS: A mouse model of UC was established using DSS. Trilobatin was administered via oral gavage. Disease severity was assessed based on body weight, disease activity index (DAI), colon length, histological detection, inflammation markers, and colonic mucosal barrier damage. Alternations in the NF-κB and PI3K/Akt pathways were detected by marker proteins. High-throughput 16S rRNA sequencing was performed to investigate the gut microbiota of mice. RESULTS: In the DSS-induced UC mice, TLB (30 µg/g) treatment significantly increased the body weight, reduced the DAI score, alleviated colon length shortening, improved histopathological changes in colon tissue, inhibited the secretion and expression of inflammation factors (TNF-α, IL-1ß, and IL-6), and increased the expression of tight-junction proteins (ZO-1 and occludin). Furthermore, TLB (30 µg/g) treatment significantly suppressed the activation of NF-κB pathway and altered the composition and diversity of the gut microbiota, as observed in the variations of the relative abundances of Proteobacteria, Actinobacteriota, and Bacteroidota, in UC mice. CONCLUSION: TLB effectively alleviates DSS-induced UC in mice. Regulation of the NF-κB pathway and gut microbiota contributes to TLB-mediated therapeutic effects. Our study not only identified a novel drug candidate for the treatment of UC, but also enhanced our understanding of the biological functions of TLB.


Asunto(s)
Colitis Ulcerosa , Sulfato de Dextran , Microbioma Gastrointestinal , FN-kappa B , Transducción de Señal , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/microbiología , Colitis Ulcerosa/patología , FN-kappa B/metabolismo , Ratones , Transducción de Señal/efectos de los fármacos , Masculino , Modelos Animales de Enfermedad , Colon/efectos de los fármacos , Colon/patología , Colon/metabolismo , Colon/microbiología , Ratones Endogámicos C57BL
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 319: 124566, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38833890

RESUMEN

Nitrite (NO2-) widely exists in our daily diet, and its excessive consumption can lead to detrimental effects on the human central nervous system and an elevated risk of cancer. The fluorescence probe method for the determination of nitrite has developed rapidly due to its simplicity, rapidity and sensitivity. Despite establishing various nitrite sensing platforms to ensure the safety of foods and drinking water, the simultaneous achievement of rapid, specific, affordable, visualizing, and on-site nitrite detection remains challenging. Here, we designed a novel fluorescent probe by using Rhodamine 800 as the fluorescent skeleton and 5-aminoindole as the specific reaction group to solve this problem. The probe shows a maximal fluorescence emission at 602 nm, thereby avoiding background emission interference when applied to food samples. Moreover, this unique probe exhibited excellent sensing capabilities for detecting nitrite. These included: a rapid response time within 3 min, a noticeable color change that the naked eye can observe, a low detection limit of 13.8 nM, and a remarkable selectivity and specificity to nitrite. Besides that, the probe can detect nitrite quantitatively in barreled drinking water, ham sausage, and pickles samples, with good recoveries ranging from 89.0 % to 105.8 %. More importantly, based on the probe fixation and signal processing technology, a portable and smart sensing platform was fabricated and made convenient and rapid analysis the content of NO2- in real samples possible. The results obtained in this work provide a new strategy for the design of high-performance nitrite probes and feasible technology for portable, rapid and visual detection of nitrite, and this probe holds the potential as a practical tool for alleviating concern regarding nitrite levels.


Asunto(s)
Colorantes Fluorescentes , Indoles , Límite de Detección , Nitritos , Espectrometría de Fluorescencia , Colorantes Fluorescentes/química , Nitritos/análisis , Indoles/química , Agua Potable/análisis , Humanos , Productos de la Carne/análisis
15.
Nano Lett ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38856112

RESUMEN

Electrical manipulation of magnetic states in two-dimensional ferromagnetic systems is crucial in information storage and low-dimensional spintronics. Spin-orbit torque presents a rapid and energy-efficient method for electrical control of the magnetization. In this letter, we demonstrate a wafer-scale spin-orbit torque switching of two-dimensional ferromagnetic states. Using molecular beam epitaxy, we fabricate two-dimensional heterostructures composed of low crystal-symmetry WTe2 and ferromagnet CrTe2 with perpendicular anisotropy. By utilizing out-of-plane spins generated from WTe2, we achieve field-free switching of the CrTe2 perpendicular magnetization. The threshold switching current density in CrTe2/WTe2 is 1.2 × 106 A/cm2, 20 times smaller than that of the CrTe2/Pt control sample even with an external magnetic field. In addition, the switching behavior can be modulated by external magnetic fields and crystal symmetry. Our findings demonstrate a controllable and all-electric manipulation of perpendicular magnetization in a two-dimensional ferromagnet, representing a significant advancement toward the practical implementation of low-dimensional spintronic devices.

16.
Int J Biol Macromol ; 273(Pt 1): 132995, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38862056

RESUMEN

Creating new adsorbents is crucial for removing contaminants from water due to increased industrialization, which has worsened water pollution in recent years. In this study, a magnetic biocomposite, Zirconium (Zr)-doped chitosan (CS)-coated iron oxide nanoparticles (Fe3O4-NPs)-peanut husk (PH)-based activated carbon (AC) (Zr-CS/Fe3O4-NPs@PH-AC), was synthesized for efficient removal of alizarin red (AR) and congo red (CR) dyes, alongside antibacterial applications. Characterization via scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis revealed micropores and mesopores development due to chemical activation of PH biomaterial and Fe3O4-NPs addition. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) identified functional groups and structural properties. Vibrating sample magnetometry (VSM) analyzed magnetic properties. Optimal conditions for AR/CR removal were determined, including Zr-CS/Fe3O4-NPs@PH-AC dose, dye dose, contact time, and temperature, achieving maximum removal percentages. Experimentally determined maximum adsorption capacities for AR and CR were 374.3 and 154.1 mg·g-1, respectively. Cytotoxicity studies affirmed the eco-friendly and non-toxic nature of the adsorbent by exhibiting the reduction in the cell viability from 100 % to 88.68 % from the 0 to 200 µg·L-1 respectively. Additionally, the biocomposite exhibited significant antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) due to magnetic NPs. The material in this study shows extreme compatibility for numerous applications.


Asunto(s)
Antibacterianos , Carbón Orgánico , Quitosano , Rojo Congo , Aguas Residuales , Contaminantes Químicos del Agua , Circonio , Quitosano/química , Circonio/química , Rojo Congo/química , Antibacterianos/farmacología , Antibacterianos/química , Adsorción , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Carbón Orgánico/química , Purificación del Agua/métodos , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Antraquinonas
17.
Curr Eye Res ; 49(9): 949-960, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38780907

RESUMEN

PURPOSE: To explore the correlation of endoplasmic reticulum stress (ERS) and oxidative stress (OS), and the protective effect of Sestrin2 (SESN2) on human lens epithelial cells (HLECs). METHODS: Tunicamycin (TM) was used to induce ERS in HLECs. 4-Phenylbutyric acid (4-PBA) was used to inhibit ERS. Eupatilin applied to HLECs as SESN2 agonist. SESN2 expression was knocked down via si-RNA in HLECs. The morphological changes of HLECs were observed by microscope. ER-tracker to evaluate ERS, ROS production assay to measure ROS, flow cytometry to calculate cell apoptosis rate. Immunofluorescence to observe Nrf2 translocation, and effects of TM or EUP on SESN2. Western blot and qPCR were used to evaluate the expression of GRP78, PERK, ATF4, CHOP, Nrf2, and SESN2 expression in HLECs with different treatment groups. RESULTS: ERS can elevate the expression of ROS and Nrf2 to induce OS. Upregulation of SESN2 was observed in ERS-mediate OS. Overexpression of SESN2 can reduce the overexpression of ERS-related protein GRP78, PERK, ATF4, proapoptotic protein CHOP, OS-related protein Nrf2, as well as ROS, and alleviate ERS injury at the same time. Whereas knockdown of SESN2 can upregulate the expression of GRP78, PERK, ATF4, CHOP, Nrf2, ROS, and deteriorate ERS damage. CONCLUSIONS: ERS can induce OS, they form a vicious cycle to induce apoptosis in HLECs, which may contribute to cataract formation. SESN2 could protect HLECs against the apoptosis by regulating the vicious cycle between ERS and OS.


Asunto(s)
Apoptosis , Western Blotting , Catarata , Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico , Células Epiteliales , Cristalino , Proteínas Nucleares , Estrés Oxidativo , Humanos , Estrés del Retículo Endoplásmico/fisiología , Cristalino/metabolismo , Cristalino/patología , Células Epiteliales/metabolismo , Catarata/metabolismo , Catarata/patología , Catarata/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Células Cultivadas , Especies Reactivas de Oxígeno/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Citometría de Flujo , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Regulación de la Expresión Génica , Sestrinas
19.
Med Biol Eng Comput ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38724769

RESUMEN

Motor imagery (MI) based brain-computer interfaces (BCIs) decode the users' intentions from electroencephalography (EEG) to achieve information control and interaction between the brain and external devices. In this paper, firstly, we apply Riemannian geometry to the covariance matrix extracted by spatial filtering to obtain robust and distinct features. Then, a multiscale temporal-spectral segmentation scheme is developed to enrich the feature dimensionality. In order to determine the optimal feature configurations, we utilize a linear learning-based temporal window and spectral band (TWSB) selection method to evaluate the feature contributions, which efficiently reduces the redundant features and improves the decoding efficiency without excessive loss of accuracy. Finally, support vector machines are used to predict the classification labels based on the selected MI features. To evaluate the performance of our model, we test it on the publicly available BCI Competition IV dataset 2a and 2b. The results show that the method has an average accuracy of 79.1% and 83.1%, which outperforms other existing methods. Using TWSB feature selection instead of selecting all features improves the accuracy by up to about 6%. Moreover, the TWSB selection method can effectively reduce the computational burden. We believe that the framework reveals more interpretable feature information of motor imagery EEG signals, provides neural responses discriminative with high accuracy, and facilitates the performance of real-time MI-BCI.

20.
Int J Nanomedicine ; 19: 4021-4040, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38736657

RESUMEN

Cataract is a leading cause of blindness globally, and its surgical treatment poses a significant burden on global healthcare. Pharmacologic therapies, including antioxidants and protein aggregation reversal agents, have attracted great attention in the treatment of cataracts in recent years. Due to the anatomical and physiological barriers of the eye, the effectiveness of traditional eye drops for delivering drugs topically to the lens is hindered. The advancements in nanomedicine present novel and promising strategies for addressing challenges in drug delivery to the lens, including the development of nanoparticle formulations that can improve drug penetration into the anterior segment and enable sustained release of medications. This review introduces various cutting-edge drug delivery systems for cataract treatment, highlighting their physicochemical properties and surface engineering for optimal design, thus providing impetus for further innovative research and potential clinical applications of anti-cataract drugs.


Asunto(s)
Catarata , Sistemas de Liberación de Medicamentos , Nanomedicina , Humanos , Catarata/tratamiento farmacológico , Nanomedicina/métodos , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Animales , Cristalino/efectos de los fármacos , Extracción de Catarata , Sistema de Administración de Fármacos con Nanopartículas/química , Soluciones Oftálmicas/química , Soluciones Oftálmicas/farmacocinética , Soluciones Oftálmicas/administración & dosificación
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