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1.
Small ; : e2401655, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38966887

RESUMEN

Despite the advantages of high tissue penetration depth, selectivity, and non-invasiveness of photothermal therapy for cancer treatment, developing NIR-II photothermal agents with desirable photothermal performance and advanced theranostics ability remains a key challenge. Herein, a universal surface modification strategy is proposed to effectively improve the photothermal performance of vanadium carbide MXene nanosheets (L-V2C) with the removal of surface impurity ions and generation of mesopores. Subsequently, MnOx coating capable of T1-weighted magnetic resonance imaging can be in situ formed through surface redox reaction on L-V2C, and then, stable nanoplatforms (LVM-PEG) under physiological conditions can be obtained after further PEGylation. In the tumor microenvironment irradiated by NIR-II laser, multivalent Mn ions released from LVM-PEG, as a reversible electronic station, can consume the overexpression of glutathione and catalyze a Fenton-like reaction to produce ·OH, resulting in synchronous cellular oxidative damage. Efficient synergistic therapy promotes immunogenic cell death, improving tumor-related immune microenvironment and immunomodulation, and thus, LVM-PEG can demonstrate high accuracy and excellent anticancer efficiency guided by multimodal imaging. As a result, this study provides a new approach for the customization of 2D surface strategies and the study of synergistic therapy mechanisms, highlighting the application of MXene-based materials in the biomedical field.

2.
J Adolesc ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622930

RESUMEN

INTRODUCTION: Following the conservation of resource theory and natural stress reduction theory, the current study investigated mediated pathways, reverse mediated pathways, and reciprocal pathways between connectedness to nature, depressive symptoms, and adolescent learning burnout via a half-longitudinal analysis, and discussed gender differences in the three models. METHODS: Two waves of data were collected in December 2022 (T1) and June 2023 (T2) for this study. The sample consisted of 1092 Chinese adolescents (52.20% girls, Mage = 13.03, SD = 1.43). Semi-longitudinal analyses were conducted to examine the relationship between connectedness to nature, depressive symptoms, and adolescent academic burnout. RESULTS: The results indicated that connectedness to nature can serve as a positive resource to alleviate the levels of depressive symptoms among adolescents and thereby decrease learning burnout. However, the protective effect of connectedness to nature was smaller, and the decreasing effect of learning burnout on connectedness to nature was stronger than the alleviating effect of connectedness to nature on learning burnout. Additionally, the study found that depressive symptoms and academic burnout have a mutually reinforcing effect over time and that the effects of this interaction are more pronounced in females. CONCLUSIONS: The present study emphasizes the protective role of nature connectedness and the detrimental effects of learning burnout in adolescents.

3.
J Environ Manage ; 359: 121107, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38728984

RESUMEN

Microbial induced concrete corrosion (MICC) is the primary deterioration affecting global sewers. Disentangling ecological mechanisms in the sewer system is meaningful for implementing policies to protect sewer pipes using trenchless technology. It is necessary to understand microbial compositions, interaction networks, functions, alongside assembly processes in sewer microbial communities. In this study, sewer wastewater samples and microbial samples from the upper part (UP), middle part (MP) and bottom part (BP) of different pipes were collected for 16S rRNA gene amplicon analysis. It was found that BP harbored distinct microbial communities and the largest proportion of unique species (1141) compared to UP and MP. The community in BP tended to be more clustered. Furthermore, significant differences in microbial functions existed in different spatial locations, including the carbon cycle, nitrogen cycle and sulfur cycle. Active microbial sulfur cycling indicated the corrosion risk of MICC. Among the environmental factors, the oxidation‒reduction potential drove changes in BP, while sulfate managed changes in UP and BP. Stochasticity dominated community assembly in the sewer system. Additionally, the sewer microbial community exhibited numerous positive links. BP possessed a more complex, modular network with higher modularity. These deep insights into microbial ecology in the sewer system may guide engineering safety and disaster prevention in sewer infrastructure.


Asunto(s)
Aguas del Alcantarillado , Aguas del Alcantarillado/microbiología , ARN Ribosómico 16S/genética , Aguas Residuales/microbiología , Ecología , Corrosión , Microbiota
4.
J Biol Inorg Chem ; 28(3): 329-343, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36877275

RESUMEN

In order to obtain the inorganic efficient antibacterial agents, the means of ion doping and morphology construction in this research are used to enhance the antibacterial property of nano-MgO, which is according to the "oxidative damage mechanism" and "contact mechanism". In this work, the nano-textured Sc2O3-MgO are synthesized by doping Sc3+ in nano-MgO lattice through calcining at 600 °C. When the Sc3+ content reaches 10%, the nanotextures on the powders surface are pretty clearly visible and uniform, and the specific surface area and the oxygen vacancy are ideal, so that the 10% Sc3+-doped powders (SM-10) has the excellent antibacterial property against E. coli and S. aureus (MBC = 0.03 mg/mL). The efficient antibacterial agents in this research have a better antibacterial effect than the 0% Sc3+-doped powders (SM-0, MBC = 0.20 mg/mL) and the commercial nano-MgO (CM, MBC = 0.40 mg/mL), which have application prospects in the field of antibacterial.


Asunto(s)
Nanopartículas , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química , Staphylococcus aureus , Escherichia coli , Oxígeno
5.
Osteoporos Int ; 34(4): 749-762, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36738335

RESUMEN

To establish a risk prediction model for residual low back pain after percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures. We used retrospective data for model construction and evaluated the model using internal validation and temporal external validation and finally concluded that the model had good predictive performance. INTRODUCTION: The cause of residual low back pain in patients with osteoporotic vertebral compression fractures (OVCFs) after PKP remains highly controversial, and our goal was to investigate the most likely cause and to develop a novel nomogram for the prediction of residual low back pain and to evaluate the predictive performance of the model. METHODS: The clinical data of 281 patients with OVCFs who underwent PKP at our hospital from July 2019 to July 2020 were reviewed. The optimal logistic regression model was determined by lasso regression for multivariate analysis, thus constructing a nomogram. Bootstrap was used to perfomance the internal validation; receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to assess the predictive performance and clinical utility of the model, respectively. Temporal external validation of the model was also performed using retrospective data from 126 patients who underwent PKP at our hospital from January 2021 to October 2021. RESULTS: Lasso regression cross-validation showed that the variables with non-zero coefficients were the number of surgical vertebrae, preoperative bone mineral density (pre-BMD), smoking history, thoracolumbar fascia injury (TLFI), intraoperative facet joint injury (FJI), and postoperative incomplete cementing of the fracture line (ICFL). The above factors were included in the multivariate analysis and showed that the pre-BMD, smoking history, TLFI, FJI, and ICFL were independent risk factors for residual low back pain (P < 0.05). The ROC and calibration curve of the original model and temporal external validation indicated a good predictive power of the model. The DCA curve suggested that the model has good clinical practicability. CONCLUSION: The risk prediction model has good predictive performance and clinical practicability, which can provide a certain basis for clinical decision-making in patients with OVCFs.


Asunto(s)
Fracturas por Compresión , Cifoplastia , Dolor de la Región Lumbar , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Humanos , Cifoplastia/efectos adversos , Fracturas por Compresión/cirugía , Fracturas por Compresión/complicaciones , Estudios Retrospectivos , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/cirugía , Nomogramas , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/cirugía , Fracturas Osteoporóticas/cirugía , Fracturas Osteoporóticas/etiología , Vértebras Lumbares/cirugía , Vértebras Lumbares/lesiones , Resultado del Tratamiento , Cementos para Huesos
6.
Sensors (Basel) ; 23(3)2023 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-36772172

RESUMEN

Developing label-free immunosensors to detect ovarian cancer (OC) by cancer antigen (CA125) is essential to improving diagnosis and protecting women from life-threatening diseases. Four types of carbon nanomaterials, such as multi-wall carbon nanotubes (MWCNTs), vapor-grown carbon fiber (VGCFs), graphite KS4, and carbon black super P (SP), have been treated with acids to prepare a carbon nanomaterial/gold (Au) nanocomposite. The AuNPs@carbon nanocomposite was electrochemically deposited on a glassy carbon electrode (GCE) to serve as a substrate to fabricate a label-free immunosensor for the detection of CA125. Among the four AuNPs@carbon composite, the AuNPs@MWCNTs-based sensor exhibited a high sensitivity of 0.001 µg/mL for the biomarker CA125 through the square wave voltammetry (SWV) technique. The high conductivity and surface area of MWCNTs supported the immobilization of AuNPs. Moreover, the carboxylic (COO-) functional groups in MWCNT improved to a higher quantity after the acid treatment, which served as an excellent support for the fabrication of electrochemical biosensors. The present method aims to explore an environmentally friendly synthesis of a layer-by-layer (LBL) assembly of AuNPs@carbon nanomaterials electrochemical immunoassay to CA125 in a clinical diagnosis at a low cost and proved feasible for point-of-care diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , Nanotubos de Carbono , Neoplasias Ováricas , Humanos , Femenino , Técnicas Biosensibles/métodos , Oro , Inmunoensayo/métodos , Neoplasias Ováricas/diagnóstico , Electrodos , Técnicas Electroquímicas/métodos , Límite de Detección
7.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37108812

RESUMEN

Due to their high porosity, large specific surface area, and structural similarity with the extracellular matrix (ECM), electrospun nanofiber membranes are often endowed with the antibacterial properties for biomedical applications. The purpose of this study was to synthesize nano-structured Sc2O3-MgO by doping Sc3+, calcining at 600 °C, and then loading it onto the PCL/PVP substrates with electrospinning technology with the aim of developing new efficient antibacterial nanofiber membranes for tissue engineering. A scanning electron microscope (SEM) and energy dispersive X-ray spectrometer (EDS) were used to study the morphology of all formulations and analyze the types and contents of the elements, and an X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR) were used for further analysis. The experimental results showed that the PCL/PVP (SMCV-2.0) nanofibers loaded with 2.0 wt% Sc2O3-MgO were smooth and homogeneous with an average diameter of 252.6 nm; the antibacterial test indicated that a low load concentration of 2.0 wt% Sc2O3-MgO in PCL/PVP (SMCV-2.0) showed a 100% antibacterial rate against Escherichia coli (E. coli).


Asunto(s)
Infecciones por Escherichia coli , Nanofibras , Humanos , Óxido de Magnesio , Nanofibras/química , Escherichia coli , Antibacterianos/farmacología , Antibacterianos/química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Inflammopharmacology ; 31(4): 1629-1645, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37150762

RESUMEN

Quercetin, a typical flavonoid derived from a common natural plant, has multiple biological activities. Previous research in animal models has demonstrated the effectiveness of quercetin in treating rheumatoid arthritis (RA). The pharmacological effects and probable mechanisms of quercetin were evaluated in this study. Three databases, PubMed, Web of Science, and Embase, were searched for relevant studies from the creation of the databases to November 2022. Methodological quality was assessed using the SYRCLE risk of bias tool. STATA 15.1 was used to perform the statistical analysis. This research included 17 studies involving 251 animals. The results indicated that quercetin was able to reduce arthritis scores, paw swelling, histopathological scores, interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-17 (IL-17), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein-1 (MCP-1), C-reactive protein (CRP), malondialdehyde (MDA), reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), nuclear factor kappa B (NF-kB) and increase interleukin-10 (IL-10), catalase (CAT), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), glutathione (GSH), and heme oxygenase-1 (HO-1). These may be related to quercetin's potential anti-inflammatory, anti-oxidative stress, and osteoprotective properties. However, more high-quality animal studies are needed to assess the effect of quercetin on RA. Additionally, the safety of quercetin requires further confirmation. Given the importance of the active ingredient, dose selection and the improvement of quercetin's bioavailability remain to be explored.


Asunto(s)
Artritis Reumatoide , Quercetina , Animales , Quercetina/farmacología , Quercetina/uso terapéutico , Estrés Oxidativo , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Antioxidantes/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Glutatión/metabolismo , FN-kappa B/metabolismo
9.
Anal Biochem ; 634: 114393, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34597616

RESUMEN

The electrochemical performance of dual layer immunosensor has been studied by employing reduced Graphene oxide (rGO) and its nanocomposites with Carbon Nanofibers (CNFs) and Carbon Nanotubes (CNTs) as supporting matrix for the detection of CA125. The immunosensor determination was based on the formation of antibody - antigen immunocomplex, a decrement in the current response was observed in accordance with the concentration of antigen. Better performance exhibited by rGO/CNF in terms of linearity (99%) and sensitivity 0.65 µA (µg mL-1)-1 can be attributed to its conductivity and surface area. The nanocomposite are employed in the detection of CA125 with linear working range of 10-32 × 10-4 µg mL-1, the limit of detection is found to be 0.28 pg mL-1 rGO nanocomposite with CNT (rGO/CNT) is studied as transducer material. rGO/CNT exhibited better linearity when compared to rGO due to its good conductivity. Thus, graphene nanocomposite transducer materials have vital application in detection of oncomarkers.


Asunto(s)
Técnicas Biosensibles/métodos , Antígeno Ca-125/análisis , Grafito/química , Nanocompuestos/química , Nanotubos de Carbono/química , Carbono/química , Conductividad Eléctrica , Técnicas Electroquímicas , Oro/química , Humanos , Inmunoensayo/métodos , Límite de Detección , Nanopartículas del Metal/química , Nanofibras/química , Espectroscopía de Fotoelectrones/métodos
10.
J Gastroenterol Hepatol ; 34(4): 791-798, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30475420

RESUMEN

BACKGROUND AND AIM: Endoscopic transmural drainage has been recognized as the first-line treatment for pancreatic fluid collection (PFC). Currently, three different types of stents have been extensively applied, including double pigtail plastic stent (PS), fully covered self-expanding metal stent (FCSEMS), and novel lumen-apposing metal stent (LAMS). Nonetheless, limited data are available about the comparison among them in terms of their clinical outcomes and safety for endoscopic ultrasound-guided drainage of PFC. METHODS: The current retrospective study was carried on 160 PFC patients undergoing endoscopic ultrasound-guided drainage from 2010 to 2018 at a single tertiary care center. Patients were divided into three groups based on different drainage ways: drainage using PS, FCSEMS, or LAMS. RESULTS: A total of 160 PFC patients (104 male and 56 female) were analyzed in this retrospective study, including 62 patients drained with PS, 28 with FCSEMS, and 70 with LAMS. Typically, the technical success (93.5% vs 96.4% vs 94.3%, P = 1.000) and treatment success rates (84.6% vs 85.2% vs 89.2%, P = 0.763) were similar between PS, FCSEMS, and LAMS. With regard to major adverse events, four patients (FCSEMS: n = 2 and LAMS: n = 2) with pseudoaneurysms developed severe bleeding; among them, 75% (3/4) of patients were observed within 2 weeks after intervention, and two patients in LAMS group died. CONCLUSIONS: There are no significant differences in the clinical outcomes of PFC patients treated with PS, FCSEMS, or LAMS. Nonetheless, severe (or even fatal) bleeding may occur at the early stage after metal stent placement, which should be paid particular attention to.


Asunto(s)
Drenaje/instrumentación , Endoscopía del Sistema Digestivo/instrumentación , Endosonografía/instrumentación , Páncreas/cirugía , Stents , Cirugía Asistida por Computador/instrumentación , Adulto , Drenaje/efectos adversos , Drenaje/métodos , Endoscopía del Sistema Digestivo/métodos , Endosonografía/efectos adversos , Endosonografía/métodos , Femenino , Estudios de Seguimiento , Hemorragia/epidemiología , Hemorragia/etiología , Hemorragia/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents/efectos adversos , Cirugía Asistida por Computador/efectos adversos , Cirugía Asistida por Computador/métodos , Resultado del Tratamiento
11.
Sensors (Basel) ; 18(12)2018 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-30558214

RESUMEN

A fiber Bragg grating (FBG)-based aluminum oxide tube packed sensor (ATPS) was developed for the fast detection of the soil moisture profile in highway slopes and subgrades. The novel ATPS consists of an aluminum oxide tube with a diameter of 5 mm, an optical fiber containing a quasi-distributed FBG sensors, a "U"-shaped resistance wire, and a flange. There are four 0.9-mm diameter holes in the ATPS. Laboratory experiments were carried out to calibrate the relationship between the thermal response of ATPS and the soil moisture content. Two laboratory rainfall validation model tests were performed to validate the ATPS for capturing the soil moisture profile in highway slopes and subgrades. During the validations, the accuracy of the ATPS was quantified, and water infiltration through grassy and grassless ground surfaces were investigated. The calibrations indicate that the ATPS can detect and record real-time changes in the highway slope and subgrade moisture after rainfall, and reveal the most dangerous zones that occur at the connection between different construction materials. The average measurement accuracy of soil moisture monitoring was 0.015 m³/m³. Please note that the connection is where cracks form easily and the soil hydraulic conductivity increases significantly. The test results also indicate that grassy cover (lawn) significantly prevents water infiltration during the first few minutes of rainfall (twelve minutes in this study), after which, however, the infiltration rate drops sharply. The influence of lawn on water infiltration depends on the soil structure, hydraulic conductivity, and rainfall time. In summary, due to its small size and fast detection, the ATPS is a portable probe that can be used for moisture monitoring in highway slopes and subgrades.

12.
Int Orthop ; 40(4): 827-34, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26112873

RESUMEN

PURPOSE: To test whether a novel guide template we designed can facilitate accurate insertion of antegrade lag screws in the fixation of acetabular posterior column fractures. METHODS: We created virtual three-dimensional reconstruction models of the pelvis from CT scan data obtained from 96 adult patients without any bony problems. A virtual cylindrical implant was placed along the longitudinal axis of the acetabular posterior column passing through the ischial tuberosity. The diameter of cylindrical implant was augmented to 6.5 mm, and the direction was adjusted until the optimal screw path was found using the reverse engineering technique. The orifice of this cylinder from the iliac fossa was determined as the entry point for the antegrade lag screw. The anatomical parameters of the screw entry path were measured and saved in .stl format. The guide template was designed according to the acetabular morphology and the measured anatomical parameters before it was put into manufacture of a solid template with the rapid prototyping technique. The feasibility and accuracy of the guide template were tested in cadaveric pelvises. Finally, the guide template was used in real surgery for five patients. Furthermore, the time required for surgery was recorded. RESULTS: Under the guide of this navigation template, antegrade lag screws were successfully placed in the posterior column of the acetabulum in the cadaveric test. And five lag screws were successfully placed in five patients. The mean time of antegrade lag screw insertion required 5.8 (3-10) min. CONCLUSIONS: Antegrade lag screws can be more accurately put into the posterior column of the acetabulum with the help of this navigation template.


Asunto(s)
Acetábulo/cirugía , Fijación Interna de Fracturas/instrumentación , Fracturas Óseas/cirugía , Técnicas Estereotáxicas/instrumentación , Acetábulo/diagnóstico por imagen , Acetábulo/lesiones , Adulto , Tornillos Óseos , Simulación por Computador , Diseño de Equipo , Femenino , Fijación Interna de Fracturas/métodos , Fracturas Óseas/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Cirugía Asistida por Computador , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
13.
Int J Biol Macromol ; 262(Pt 2): 130033, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342261

RESUMEN

Antibacterial and active packaging materials have gained significant research attention in response to the growing interest in food packaging. In this investigation, we developed hydrogel packaging materials with antibacterial and antioxidant properties by incorporating chitooligosaccharide (COS) and fish skin gelatin (FSG) nanofiber membranes, which readily absorbed water and exhibited swelling characteristics. The nanofiber membranes were fabricated by electrospinning technology, embedding COS within FSG, and subsequently crosslinked through the Maillard reaction facilitated by the addition of glucose. The behavior of conductivity, viscosity, and surface tension in the spinning solutions was analyzed to understand their variation patterns. Scanning electron microscopy (SEM) results revealed that the crosslinked COS/FSG nanofiber membranes possessed a uniform yet disordered fiber structure, with the diameter of the nanofibers increasing as the COS content increased. Remarkably, when the COS content reached 25 %, the COS/FSG nanofiber membranes (CF-C-25) exhibited a suitable fiber diameter of 437.16 ± 63.20 nm. Furthermore, the thermal crosslinking process involving glucose supplementation enhanced the hydrophobicity of CF-C-25. Upon hydration, the CF-H-25 hydrogel displayed a distinctive porous structure, exhibiting a remarkable swelling rate of 954 %. Notably, the inclusion of COS significantly augmented the antibacterial and antioxidant properties of the hydrogel-based nanofiber membranes. CF-H-25 demonstrated an impressive growth inhibition of 90.56 ± 5.91 % against E. coli, coupled with excellent antioxidant capabilities. In continuation, we performed a comprehensive analysis of the total colony count, pH, TVB-N, and TBA of crucian carp. The CF-H-25 hydrogel proved highly effective in extending the shelf life of crucian carp by 2-4 days, suggesting its potential application as an edible membrane for aquatic product packaging.


Asunto(s)
Quitosano , Nanofibras , Oligosacáridos , Sulfanilamidas , Animales , Nanofibras/química , Gelatina/química , Antioxidantes/farmacología , Antioxidantes/química , Escherichia coli , Hidrogeles/farmacología , Antibacterianos/farmacología , Quitina , Glucosa
14.
Environ Sci Pollut Res Int ; 31(9): 13075-13088, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38240967

RESUMEN

Sewer systems play vital roles in wastewater treatment facilities, and the microbial communities contribute significantly to the transformation of domestic wastewater. Therefore, this study conducted a 180-day experiment on a sewer system and utilized the high-throughput sequencing technology to characterize the microbial communities. Additionally, community assembly analysis was performed to understand the early-stage dynamics within the sewer system. The results demonstrated that the overall diversity of microbial communities exhibited fluctuations as the system progressed. The dominant phyla observed were Chloroflexi, Bacteroidetes, Firmicutes, and Proteobacteria, accounting for over 85.4% of the total relative abundances. At the genus level, bacteria associated with fermentation displayed a high relative abundance, particularly during days 75 to 180. A random-forest machine-learning model identified a group of microbes that confirmed the substantial contribution of fermentation. During the process of fermentation, microorganisms predominantly utilized propionate formation as the main pathway for acidogenesis, followed by acetate and butyrate formation. In terms of nitrogen and sulfur cycles, dissimilatory nitrate reduction and assimilatory sulfate reduction played significant roles. Furthermore, stochastic ecological processes had a dominant effect during the experiment. Dispersal limitation primarily governed the assembly process almost the entire experimental period, indicating the strong adaptability and metabolic plasticity of microorganisms in response to environmental variations. This experiment provides valuable insights into the metabolic mechanisms and microbial assembly associated with sewer systems.


Asunto(s)
Bacterias , Microbiota , Bacterias/metabolismo , Proteobacteria , Aguas Residuales , Bacteroidetes
15.
Food Funct ; 15(4): 2052-2063, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38293823

RESUMEN

Green tea polyphenol (-)-Epigallocatechin-3-gallate (EGCG) has been well studied for its biological activities in the prevention of chronic diseases. However, the biological activities of EGCG oxidation-derived polymers remain unclear. Previously, we found that these polymers accumulated in intraperitoneal tissues after intraperitoneal injection and gained an advantage over native EGCG in increasing insulin sensitivity via regulating the renin-angiotensin system (RAS) in type 2 diabetic mice. The present study determined the pro-apoptosis activities and anticancer mechanisms of the EGCG oxidation-derived polymer preparation (the >10 kDa EGCG polymers) in digestive tract cancer cells. Upon incubation of the >10 kDa EGCG polymers with CaCo2 colon cancer cells, these polymers coated the cell surface and regulated multiple components of the RAS in favor of cancer inhibition, including the downregulation of angiotensin-converting enzyme (ACE), angiotensin-II (AngII) and AngII receptor type 1 (AT1R) in the pro-tumor axis, as well as the upregulation of angiotensin-converting enzyme 2 (ACE2) and angiotensin1-7 (Ang(1-7)) in the anti-tumor axis. The treatment also markedly increased angiotensinogen (AGT), which is the precursor of the angiotensin peptides. The regulation of these RAS components occurred prior to apoptosis. Similar pro-apoptotic mechanisms of the >10 kDa EGCG polymers, were also observed in TCA8113 oral cancer cells. The >10 kDa EGCG polymers exhibited compromised activities in scavenging or initiating reactive oxygen species compared to EGCG, but gained a higher reactivity toward sulfhydryl groups, including protein cysteine thiols. We propose that the polymers bind onto the cell surface and regulate multiple RAS components by reacting with the sulfhydryl groups on the ectodomains of transmembrane proteins.


Asunto(s)
Catequina/análogos & derivados , Diabetes Mellitus Experimental , Neoplasias , Humanos , Ratones , Animales , Sistema Renina-Angiotensina , Células CACO-2 , Angiotensina II/farmacología , Apoptosis , Tracto Gastrointestinal
16.
Food Funct ; 15(4): 2181-2196, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38315103

RESUMEN

(-)-Epigallocatechin-3-gallate (EGCG) is a major polyphenol in tea and exerts several health-promoting effects. It easily autoxidizes into complex polymers and becomes deactivated due to the presence of multiple phenolic hydroxyl structures. Nonetheless, the morphology and biological activity of complex EGCG polymers are yet to be clarified. The present study demonstrated that EGCG autoxidation self-assembled nanoparticles (ENPs) exhibit antioxidant activity in vitro and hepatic REDOX homeostasis regulation activity in vivo. Also, the formation of ENPs during the EGCG autoxidation process was based on the intermolecular interaction forces that maintain the stability of the nanoparticles. Similar to EGCG, ENPs are scavengers of reactive oxygen species and hydroxyl radicals in vitro and also regulate hepatic REDOX activity through liver redox enzymes, including thioredoxin reductase (TrxR), thioredoxin (Trx), glutathione reductase (GR), glutaredoxin (Grx), and glutathione S-transferase (GST) in vivo. Moreover, ENPs activate the NRF2 antioxidant-responsive element pathway, exerting a detoxification effect at high doses. Unlike EGCG, ENPs do not cause liver damage at low doses and also maintain liver biosafety at high doses through self-assembly, forming large particles, which is supported by the unchanged levels of liver damage biomarkers, including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver γ-phosphorylated histone 2AX (γ-H2AX), and P53-related genes (Thbs, MDM2, P53, and Bax). Collectively, these findings revealed that ENPs, with adequate biosafety and regulation of hepatic redox activity in vivo, may serve as substitutes with significant potential for antioxidant applications or as food additives to overcome the instability and liver toxicity of EGCG.


Asunto(s)
Catequina , Catequina/análogos & derivados , Nanopartículas , Antioxidantes/farmacología , Antioxidantes/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Hígado/metabolismo , Oxidación-Reducción , Catequina/farmacología , Catequina/metabolismo , Polímeros/farmacología
17.
Polymers (Basel) ; 15(9)2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37177357

RESUMEN

Lithium cobalt oxide (LiCoO2, LCO) has been widely used in electronic markets due to its high energy density and wide voltage range applications. Recently, high-voltage (HV, >4.5 V) operation has been required to obey the requirements of high energy density and cycle life in several applications such as electric vehicles and energy storage. However, the HV operation causes structure instability due to the over de-lithiation of LCO, as well as decomposing common carbonate solvents, thereby incurring the decay of battery performance. Moreover, a distortion of the CoO6 octahedra of LCO during de-lithiation induces a rehybridization of the Co 3d and O 2p orbitals. According to above reasons, decreasing the Co-O covalent bond promptly triggers high risks that significantly limit further use of LCO. In this research, an organic surface reinforcement by using bismaleimide-uracil (BU) that electrochemically forms a cathode electrolyte interphase (CEI) on LCO was explored. The results of electrochemical impedance spectroscopy and battery performance, such as the c-rate and cyclability tests, demonstrated that the modified CEI formed from BU significantly prevents the distortion of CoO6 octahedra. X-ray photoelectronic spectroscopy and in situ XAS indicated less LiF formation and higher bond energy of Co-O improved. Finally, the differential scanning calorimetry showed the onset temperature of decomposition of LCO was extended from 245 to 270 °C at 100% state of charge, which is about a 25 °C extension. The exothermic heat of LCO decreased by approximately 30% for high-safety use. This research confirms that the BU is eligible for high voltage (>4.5 V) LCO and presents outstanding electrochemical properties and safety performances.

18.
Chemosphere ; 340: 139864, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37619759

RESUMEN

Red clay, a widely distributed soil, weakens significantly when exposed to water. This poses challenges for using it as a foundation for urban infrastructure, as rainwater scouring, infiltration, and external loads can cause uneven settlement and landslides, compromising structural integrity. To address this issue, we propose the use of a green highly permeable water-soluble polyurethane material (PSP) as an alternative to conventional curing agents. We conducted a series of tests to evaluate the efficacy of PSP in improving the mechanical properties of red clay. Acoustic emission tests were used to examine the failure mode of PSP-stabilized red clay, while scanning electron microscopy provided microscopic insights into clay stabilization mechanisms. The triaxial test results establish empirical relationships between strength, stiffness, toughness, and control parameters (PSP content, moisture content, and confining pressure) of the stabilized clay. We found that PSP-stabilized soils exhibit ductile failure and strain hardening, with PSP curing agents effectively enhancing clay strength and stiffness within a 3-day curing period. Univariate analysis reveals positive correlations between peak energy absorption values, peak stress rates, and PSP content, while showing a negative correlation with moisture content. Confining pressure variations have relatively little effect on peak stress ratios of PSP soils, and PSP soil stiffness minimally influences confining pressure as PSP content increases. Importantly, PSP treatment significantly increases ductility compared to untreated clay soils, distinguishing PSP soils from hydric soils.


Asunto(s)
Poliuretanos , Suelo , Arcilla , Acústica , Agua
19.
Polymers (Basel) ; 15(6)2023 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-36987273

RESUMEN

In this study, the uniaxial compression and cyclic loading and unloading experiments were conducted on the non-water reactive foaming polyurethane (NRFP) grouting material with a density of 0.29 g/cm3, and the microstructure was characterized using scanning electron microscope (SEM) method. Based on the uniaxial compression and SEM characterization results and the elastic-brittle-plastic assumption, a compression softening bond (CSB) model describing the mechanical behavior of micro-foam walls under compression was proposed, and it was assigned to the particle units in a particle flow code (PFC) model simulating the NRFP sample. Results show that the NRFP grouting materials are porous mediums consisting of numerous micro-foams, and with the increasing density, the diameter of the micro-foams increases and the micro-foam walls become thicker. Under compression, the micro-foam walls crack, and the cracks are mainly perpendicular to the loading direction. The compressive stress-strain curve of the NRFP sample contains the linear increasing stage, yielding stage, yield plateau stage, and strain hardening stage, and the compressive strength and elastic modulus are 5.72 MPa and 83.2 MPa, respectively. Under the cyclic loading and unloading, when the number of cycles increases, the residual strain increases, and there is little difference between the modulus during the loading and unloading processes. The stress-strain curves of the PFC model under uniaxial compression and cyclic loading and unloading are consistent with the experimental ones, well indicating the feasibility of using the CSB model and PFC simulation method to study the mechanical properties of NRFP grouting materials. The failure of the contact elements in the simulation model causes the yielding of the sample. The yield deformation propagates almost perpendicular to the loading direction and is distributed in the material layer by layer, which ultimately results in the bulging deformation of the sample. This paper provides a new insight into the application of the discrete element numerical method in NRFP grouting materials.

20.
Comput Biol Med ; 167: 107601, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37924642

RESUMEN

BACKGROUND: The network meta-analysis (NMA) investigated the efficacy of six food supplements, namely glutamine, arginine, lactoferrin, prebiotics, synbiotics, and probiotics, in preventing necrotizing enterocolitis in premature infants. METHODS: MEDLINE, Embase, and Cochrane Library were searched. Randomized controlled trials comparing different food supplements for premature infants were included. RESULTS: Probiotics (OR, 0.47; 95% CrI, 0.33-0.63), arginine (OR, 0.38; 95% CrI, 0.14-0.98), glutamine (OR, 0.30; 95% CrI, 0.079-0.90), and synbiotics (OR, 0.13; 95% CrI, 0.037-0.37). were associated with a decreased incidence of NEC. Only probiotics (OR, 0.81; 95% CrI, 0.69-0.95) and lactoferrin (OR, 0.74; 95% CrI, 0.54-0.92) achieved lower risk of sepsis. Probiotics (OR, 0.58; 95% CrI, 0.40-0.79), prebiotics (OR, 0.23; 95% CrI, 0.043-0.86), and synbiotics (OR, 0.15; 95% CrI, 0.035-0.50) were associated with lower odds of mortality. Probiotics (MD, -2.3; 95% CrI: -3.7- -0.63) appeared to have earlier age of attainment of full feeding. CONCLUSIONS: Based on this NMA, probiotics and synbiotics had the potential to be the top two preferable food supplements.


Asunto(s)
Enterocolitis Necrotizante , Enfermedades del Recién Nacido , Probióticos , Recién Nacido , Humanos , Enterocolitis Necrotizante/prevención & control , Enterocolitis Necrotizante/epidemiología , Metaanálisis en Red , Lactoferrina , Glutamina , Recien Nacido Prematuro , Probióticos/uso terapéutico , Arginina
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