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1.
Ultrasound Med Biol ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38834493

RESUMEN

OBJECTIVE: Echocardiographic videos are commonly used for automatic semantic segmentation of endocardium, which is crucial in evaluating cardiac function and assisting doctors to make accurate diagnoses of heart disease. However, this task faces two distinct challenges: one is the edge blurring, which is caused by the presence of speckle noise or excessive de-noising operation, and the other is the lack of an effective feature fusion approach for multilevel features for obtaining accurate endocardium. METHODS: In this study, a deep learning model, based on multilevel edge perception and calibration fusion is proposed to improve the segmentation performance. First, a multilevel edge perception module is proposed to comprehensively extract edge features through both a detail branch and a semantic branch to alleviate the adverse impact of noise. Second, a calibration fusion module is proposed that calibrates and integrates various features, including semantic and detailed information, to maximize segmentation performance. Furthermore, the features obtained from the calibration fusion module are stored by using a memory architecture to achieve semi-supervised segmentation through both labeled and unlabeled data. RESULTS: Our method is evaluated on two public echocardiography video data sets, achieving average Dice coefficients of 93.05% and 93.93%, respectively. Additionally, we validated our method on a local hospital clinical data set, achieving a Pearson correlation of 0.765 for predicting left ventricular ejection fraction. CONCLUSION: The proposed model effectively solves the challenges encountered in echocardiography by using semi-supervised networks, thereby improving the segmentation accuracy of the ventricles. This indicates that the proposed model can assist cardiologists in obtaining accurate and effective research and diagnostic results.

2.
Chem Asian J ; 19(12): e202400180, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38650439

RESUMEN

This review explores the potential of using different types of ash, namely fly ash, biomass ash, and coal ash etc., as mediums for CO2 capture and sequestration. The diverse origins of these ash types - municipal waste, organic biomass, and coal combustion - impart unique physicochemical properties that influence their suitability and efficiency in CO2 absorption. This review first discusses the environmental and economic implications of using ash wastes, emphasizing the reduction in landfill usage and the transformation of waste into value-added products. Then the chemical/physical treatments of ash wastes and their inherent capabilities in binding or reacting with CO2 are introduced, along with current methodologies utilize these ashes for CO2 sequestration, including mineral carbonation and direct air capture techniques. The application of using ash wastes for CO2 capture are highlighted, followed by the discussion regarding challenges associated with ash-based CO2 absorption approach. Finally, the article projects into the future, proposing innovative approaches and technological advancements needed to enhance the efficacy of ash in combating the increasing CO2 levels. By providing a comprehensive analysis of current strategies and envisioning future prospects, this review aims to contribute to the field of sustainable CO2 absorption and environmental management.

3.
J Org Chem ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38327084

RESUMEN

Transition-metal-catalyzed asymmetric cross-coupling represents a powerful strategy for C-C bond formation and the synthesis of enantiomerically pure molecules. Here, we report a dual nickel/photoredox-catalyzed enantioselective reductive cross-coupling of aryl halides with α-bromobenzoates, readily generated from aliphatic aldehydes, to provide diverse chiral secondary benzylic alcohols that are important motifs in bioactive natural products and pharmaceuticals. This dual catalytic system features mild conditions, good functional group tolerance, broad substrate scope, excellent enantiocontrol, and avoidance of stoichiometric metal reductants, presenting great potential for late-stage functionalization of complex molecules.

4.
J Org Chem ; 89(4): 2223-2231, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38326966

RESUMEN

A nickel-catalyzed reductive anti-arylative cyclization of alkynyl enones with aryl halides has been developed. The reaction avoids the use of stoichiometric organometallic reagents and has a broad reaction scope and high functional group tolerance. This method offers an efficient way to access a variety of synthetically useful carbocycles that are widely found in many natural products and biologically active molecules.

5.
Environ Pollut ; 342: 123132, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38081377

RESUMEN

Utilizing digestate as a fertilizer enhances soil nutrient content, improves fertility, and minimizes nutrient runoff, mitigating water pollution risks. This alternative approach replaces commercial fertilizers, thereby reducing their environmental impact and lowering greenhouse gas emissions associated with fertilizer production and landfilling. Herein, this study aimed to evaluate the impact of various soil amendments, including carbon fractions from waste materials (biochar, compost, and cocopeat), and food waste anaerobic digestate application methods on tomato plant growth (Solanum lycopersicum) and soil fertility. The results suggested that incorporating soil amendments (biochar, compost, and cocopeat) into the potting mix alongside digestate application significantly enhances crop yields, with increases ranging from 12.8 to 17.3% compared to treatments without digestate. Moreover, the combination of soil-biochar amendment and digestate application suggested notable improvements in nitrogen levels by 20.3% and phosphorus levels by 14%, surpassing the performance of the those without digestate. Microbial analysis revealed that the soil-biochar amendment significantly enhanced biological nitrification processes, leading to higher nitrogen levels compared to soil-compost and soil-cocopeat amendments, suggesting potential nitrogen availability enhancement within the rhizosphere's ecological system. Chlorophyll content analysis suggested a significant 6.91% increase with biochar and digestate inclusion in the soil, compared to the treatments without digestate. These findings underscore the substantial potential of crop cultivation using soil-biochar amendments in conjunction with organic fertilization through food waste anaerobic digestate, establishing a waste-to-food recycling system.


Asunto(s)
Eliminación de Residuos , Suelo , Fertilizantes/análisis , Agricultura/métodos , Alimentos , Carbón Orgánico , Nitrógeno/análisis , Nutrientes/análisis
7.
Environ Res ; 244: 117946, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38104915

RESUMEN

The industrialization of hydrogen production through dark fermentation of food waste faces challenges, such as low yields and unpredictable fermentation processes. Biochar has emerged as a promising green additive to enhance hydrogen production in dark fermentation. Our study demonstrated that the introduction of Fe-modified biochar (Fe-L600) significantly boosted hydrogen production during thermophilic dark fermentation of food waste. The addition of Fe-L600 led to a remarkable 31.19% increase in hydrogen yield and shortened the time needed for achieving stabilization of hydrogen production from 18 h to 12 h. The metabolite analysis revealed an enhancement in the butyric acid pathway as the molar ratio of acetic acid to butyric acid decreased from 3.09 to 2.69 but hydrogen yield increased from 57.12 ± 1.48 to 76.78 ± 2.77 mL/g, indicating Fe-L600 improved hydrogen yield by regulating crucial metabolic pathways of hydrogen production. The addition of Fe-L600 also promoted the release of Fe2+ and Fe3+ and increased the concentrations of Fe2+ and Fe3+ in the fermentation system, which might promote the activity of hydrogenase and ferredoxin. Microbial community analysis indicated a substantial increase in the relative abundance of Thermoanaerobacterium after thermophilic dark fermentation. The relative abundances of microorganisms responsible for hydrolysis and acidogenesis were also observed to be improved in the system with Fe-L600 addition. This research provides a feasible strategy for improving hydrogen production of food waste and deepens the understanding of the mechanisms of biochar.


Asunto(s)
Carbón Orgánico , Alimento Perdido y Desperdiciado , Eliminación de Residuos , Fermentación , Alimentos , Ácido Butírico , Hidrógeno/metabolismo
8.
Sci Total Environ ; 905: 167294, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37741387

RESUMEN

Microbial extracellular respiration is an important energy metabolism on earth, which is significant for the elemental biogeochemical cycle. Herein, extracellular Fe(III) and electrode respiration were confirmed in Thermoanaerobacterium thermosaccharolyticum MJ2. The intra/extracellular electron transfer (IET/EET) mechanism of MJ2 was investigated by comparative genomic analysis for the first time. Morphological characterization and electrochemical properties of anode illustrated that MJ2 generated bio-electricity by forming a biofilm. The respiration chain inhibition and enzyme activity tests showed that hydrogenase with cytochrome c (Cyt-c) was involved in IET of MJ2. Noteworthily, the exogenous Cyt-c increased hydrogenase activity to promote bio-electricity generation by 92.84 %. The Cyt-c gene synteny between MJ2 and another well-known exoelectrogen (Thermincola potens JR) indicated that Cyt-c bound to the outer membrane mediated the formation of biofilm involved in EET of MJ2. This study broadened the understanding of microbial extracellular respiration diversity and provided new insights to explore the electron transfer pathways of exoelectrogens.


Asunto(s)
Fuentes de Energía Bioeléctrica , Hidrogenasas , Thermoanaerobacterium , Electrones , Compuestos Férricos , Clostridium , Genómica , Electrodos , Biopelículas
9.
Biotechnol Appl Biochem ; 70(6): 1817-1829, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37278155

RESUMEN

Astaxanthin is widely used in food, aquaculture, cosmetics, and pharmaceuticals due to its strong antioxidant activity and coloring ability, but its production from Phaffia rhodozyma remains the main challenge due to the high fermentation cost and low content of carotenoid. In this study, the production of carotenoids from food waste (FW) by a P. rhodozyma mutant was investigated. P. rhodozyma mutant screened by UV mutagenesis and flow cytometry could stably produce high carotenoids at 25°C, with carotenoid production (32.9 mg/L) and content (6.7 mg/g), respectively, increasing by 31.6% and 32.3% compared with 25 mg/L and 5.1 mg/g of wild strain. Interestingly, the carotenoid production reached 192.6 mg/L by feeding wet FW, which was 21% higher than batch culture. The 373 g vacuum freeze-dried products were obtained from the fermentation of 1 kg FW by P. rhodozyma, which contained 784 mg carotenoids and 111 mg astaxanthin. The protein, total amino acids, and essential amino acids content of the fermentation products were 36.6%, 40.5%, and 18.2% (w/w), respectively, and lysine-added fermentation products had the potential of high-quality protein feed source. This study provides insights for the high-throughput screening of mutants, astaxanthin production, and the development of the feed potential of FW.


Asunto(s)
Basidiomycota , Eliminación de Residuos , Citometría de Flujo , Alimento Perdido y Desperdiciado , Alimentos , Carotenoides/metabolismo , Basidiomycota/genética , Basidiomycota/metabolismo
12.
Bioresour Technol ; 351: 127072, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35351565

RESUMEN

The multifunctional roles of biochar as an additive in improving the performance of anaerobic digestion (AD) has not been perfectly understood. In this study, the effects of different biochars on AD and the enhanced mechanisms were explored. The CH4 productions were significantly improved with an increase of 45.9%, 28.3% and 16.5% by amendment with biochar pyrolyzed at 300℃ (BC300), 450℃ (BC450) and 600℃ (BC600), respectively. The tightly-bound communities were established on biochar at the initial stage of fermentation and functional microbes were selectively enriched/colonized in biochar-amended systems. Distinctive loosely-bound microbial communities were observed in BC300 and BC600 amended systems, among which electroactive Desulforhabdus and Clostridiales were the dominant bacteria. Biochar amendments also led to the formation of distinctive spatial ecological niches and the selection preference of microbes for specific spatial locations. These results provided new insights in revealing the potential mechanisms of enhanced AD performance by biochar amendment.


Asunto(s)
Metano , Microbiota , Anaerobiosis , Carbón Orgánico , Electrones , Oxidación-Reducción
13.
Neural Netw ; 150: 102-111, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35306462

RESUMEN

The main purpose of multi-view subspace clustering is to reveal the intrinsic low-dimensional architecture of data points according to their multi-view characteristics. Exploring the potential relationship from views is one of the most essential research focuses of the multi-view task. To better utilize the complementary and consistency information from distinct views, we propose a novel robust subspace clustering approach based on consensus representation and orthogonal diversity (RMSCCO). A novel defined orthogonality term is adopted to improve the diversity and decrease the redundance of learning subspace representation. The consensus representation and subspace learning are integrated into one unified framework to characterize the consistency from views. The grouping-enhanced representation is utilized to maintain the local geometric architecture in the original data space. The ℓ2,1-norm regularizer constraint to the noise is applied to improve the robustness. Finally, an optimization algorithm is exploited to solve RMSCCO with the Alternating Direction Method of Multipliers (ADMM). Extensive experimental results on six challenging datasets demonstrate that our approach has accomplished highly qualified performance.


Asunto(s)
Algoritmos , Aprendizaje , Análisis por Conglomerados , Consenso
14.
Colloids Surf B Biointerfaces ; 209(Pt 1): 112214, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34801978

RESUMEN

Biodegradable and absorbable sutures have been widely used in surgical procedures. However, for the repair of ligament and tendon injures, the biodegradable suture cannot provide sufficient mechanical support to close the wound for a long period of time which is important to completely heal the tissue. Herein, we develop a simple method that makes a surface coating to prolong the degradation of the suture in vivo. Polylactic acid (PLLA) and Polycaprolactone (PCL) were successfully coated to a commercial degradable polydioxanone (PDO) suture in this study, which was confirmed by Fourier transform infrared spectra (FTIR). Scanning electron microscopy (SEM) was used to observe the smooth surface of the coated sutures. Moreover, live/dead assay of human fibroblasts after co-culturing with the modified/unmodified sutures showed fairly good cellular activity. In vivo study demonstrates the degradation properties of sutures were significantly changed after the surface coating. The raw suture exhibited the fastest degradation in 12 weeks, showing significantly decline in mechanical strength. Interestingly, the PCL-coated suture was able to maintain more than 20% of its original tensile strength after 12 weeks' implantation. In addition, in vivo results of PCL-coated sutures also showed less inflammatory cell infiltration and less surface inflammation. These findings indicate the one step suture-coating method could be feasibly for the development of clinical equipment.


Asunto(s)
Técnicas de Sutura , Suturas , Humanos , Tendones/cirugía , Resistencia a la Tracción
15.
J Oncol ; 2021: 3578949, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34925508

RESUMEN

Ewing sarcoma (ES) is one of the most common bone cancers in adolescents and children. Growing evidence supports the view that metabolism pathways play critical roles in numerous cancers (He et al. (2020)). However, the correlation between metabolism-associated genes (MTGs) and Ewing sarcoma has not been investigated systematically. Here, based on the univariate Cox regression analysis, we get survival genes from differentially expressed genes (DEGs) from Gene Expression Omnibus (GEO) cohort. Multivariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were employed to establish the MTG signature. Comprehensive survival analyses including receiver operating characteristic (ROC) curves and Kaplan-Meier analysis were applied to estimate the independent prognostic value of the signature. The ICGC cohort served as the validation cohort. A nomogram was constructed based on the risk score of the MTG signature and other independent clinical variables. The CIBERSORT algorithm was applied to estimate immune infiltration. In addition, we explored the correlation between MTG signature and immune checkpoints. Collectively, this work presents a novel MTG signature for prognostic prediction of Ewing sarcoma. It also suggests six genes that are potential prognostic indicators and therapeutic targets for ES.

16.
Front Bioeng Biotechnol ; 9: 690409, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34631675

RESUMEN

Osteosarcoma is a big challenge on clinical treatment. The breakthrough associated with osteosarcoma in basic research and translational research depends on the reliable establishment of an animal model, whereby mice are frequently used. However, a traditional animal modeling technique like tumor cell suspension injection causes batch dynamics and large mice consumption. Here, we suggested a novel approach in establishing an orthotropic osteosarcoma model in nude mice rapidly by cell sheet culture and transplantation. Our findings demonstrated that the 143b osteosarcoma cell sheet orthotopically implanted into the nude mice could form a visible mass within 10 days, whereas it took over 15 days for a similar amount of cell suspension injection to form a visible tumor mass. Living animal imaging results showed that a tumor formation rate was 100% in the cell sheet implantation group, while it was 67% in the cell suspension injection group. The formed tumor masses were highly consistent in both growth rate and tumor size. Massive bone destruction and soft tissue mass formation were observed from the micro CT analysis, suggesting the presence of osteosarcoma. The histopathological analysis demonstrated that the orthotropic osteosarcoma model mimicked the tumor bone growth, bone destruction, and the lung metastasis. These findings imply that such a cell sheet technology could be an appropriate approach to rapidly establish a sustainable orthotropic osteosarcoma model for tumor research and reduce mice consumption.

17.
J Mol Histol ; 52(5): 1081-1095, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34297260

RESUMEN

The apoptosis of mature osteocytes is the main factor causing damage to the microstructure of cortical bone in glucocorticoid-induced osteoporosis (GIOP). Our previous research found damaged areas and empty osteocytes lacunae in the tibial cortical bone of GIOP mice. However, the specific mechanism has not been clarified. Recently, a study showed that the quality of the cortical bone significantly increased by knocking out Notum, a gene encoding α/ß hydrolase. However, it is not clear whether Notum affects cortical bone remodeling by participating in glucocorticoids (GCs)-induced apoptosis of osteocytes. The present study aimed to explore the correlation between Notum, osteocytes apoptosis, and cortical bone quality in GIOP. Prednisolone acetate was intragastrically administered to mice for two weeks. Histochemical staining was applied to evaluate changes in GIOP and Notum expression. Osteocytes were stimulated with prednisolone, and cell viability was assessed via CCK8. Hoechst 33342/PI staining, flow cytometry, RT-PCR, and western blot were used to detect osteocytes apoptosis, siRNA transfection efficiency, and expressions of pathway related factors. The results showed that the number of empty osteocytes lacunae increased in GIOP mice. TUNEL-stained apoptotic osteocytes and Notum immuno-positive osteocytes were also observed. Furthermore, prednisolone was found to promote Notum expression and osteocytes apoptosis in vitro. Knocking down Notum via siRNA partially restored osteocytes apoptosis and phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/glycogen synthase kinase-3ß (GSK3ß)/ß-catenin pathway. These findings showed GCs-induced osteocytes apoptosis by promoting Notum expression and inhibiting PI3K/AKT/GSK3ß/ß-catenin pathway. Thus, Notum might be a potential therapeutic target for the treatment of GIOP.


Asunto(s)
Apoptosis , Esterasas/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Osteocitos/citología , Osteocitos/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Prednisolona/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatasa Alcalina/metabolismo , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Osteocitos/efectos de los fármacos , Osteoporosis/inducido químicamente , Osteoporosis/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal , Fosfatasa Ácida Tartratorresistente/metabolismo
18.
Water Res ; 202: 117440, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34304072

RESUMEN

The influence of biochar (BC) on anerobic digestion (AD) of organic wastes have been widely studied. However, the effect of BC on rate-limiting step during AD of lignocellulosic waste, i.e. the hydrolysis and acidogenesis step, is rarely studied and the underlying mechanisms have not been investigated. In this study, the benefits of BC with respect to dark fermentative hydrogen production were explored in a fermentation system by a heat-shocked consortium from sewage sludge (SS) with pretreated sugarcane bagasse (PSCB) as carbon source. The results showed that biochar boosted biohydrogen production by 317.1% through stimulating bacterial growth, improving critical enzymatic activities, manipulating the ratio of NADH/NAD+ and enhancing electron transfer efficiency of fermentation system. Furthermore, cellulolytic Lachnospiraceae was efficiently enriched and electroactive bacteria were selectively colonized and the ecological niche was formed on the surface of biochar. Synergistic effect between functional bacteria and extracellular electron transfer (EET) in electroactive bacteria were assumed to be established and maintained by biochar amendment. This study shed light on the underlying mechanisms of improved performance of biohydrogen production from lignocellulosic waste during mesophilic dark fermentation by BC supplementation.


Asunto(s)
Saccharum , Bacterias , Celulosa , Carbón Orgánico , Electrones , Fermentación , Hidrógeno
19.
Bioresour Technol ; 326: 124751, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33535152

RESUMEN

Pretreatment plays a key role in biofuel production from lignocellulosic biomass. In this study, the main factors of peroxyformic acid (PA) pretreatment were optimized in the light of enzymolysis efficiency and composition analysis of pretreated sugarcane bagasse (SCB). Lignin was significantly removed (59.0%) and a complete saccharification level (103.6%) was obtained for the pretreated SCB with slight cellulose loss (9.2%) under the optimized pretreatment conditions. The effects of PA pretreatment on the structural characteristics of SCB were also studied and the digestibility of pretreated SCB was also evaluated by dark fermentative hydrogen production with an enriched anaerobic cellulolytic microbial consortium MC1. The hydrogen production increased by 195.5% (based on initial SCB) and the abundance of dominant hemicellulose-degradation genus Thermoanaerobacterium increased from 23.8% to 40.2% due to the remaining and accessible hemicellulose in PA pretreated SCB.


Asunto(s)
Celulasa , Saccharum , Celulosa , Formiatos , Hidrógeno , Hidrólisis , Lignina
20.
J Bone Oncol ; 27: 100348, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33598394

RESUMEN

BACKGROUND: Osteosarcoma is a primary cause of cancer-associated death in children and adolescents worldwide. Long non-coding RNAs SNHG16 (lncRNA SNHG16) and integrin subunit-a 6 (ITGA6) are recently reported to be involved in the tumorigenesis of osteosarcoma by multiple mechanisms. However, the correlation between SNHG16 and ITGA6 in osteosarcoma remains undetermined. METHODS: Expression of miR-488, SNHG16 and ITGA6, as well as epithelial-mesenchymal transition (EMT) associated markers in osteosarcoma tissues and cell lines were examined by qRT-PCR or Western blotting. Effects of miR-488, SNHG16 and ITGA6 on cell migration, invasion were evaluated by wound-healing assay and transwell assay. Bioinformatics analysis and dual-luciferase reported assays were applied to assess the interaction among miR-488, SNHG16 and ITGA6. RNA immunoprecipitation (RIP) was also used to verify SNHG16 and miR-488 interaction. Finally, animal study was used to detect the effect of SNHG16 on osteosarcoma in vivo. RESULTS: SNHG16 and ITGA6 were significantly increased while miR-488 was decreased in osteosarcoma. ITGA6 was screened as a target gene of miR-488, and SNHG16 was sponged by miR-488 in osteosarcoma cells. MiR-488 overexpression and SNHG16 knockdown suppressed migration, invasion and EMT of osteosarcoma cells. Moreover, rescue assays proved that the influences of SNHG16 on osteosarcoma cells migration, invasion and EMT were dependent on miR-488 and ITGA6. In addition, the promotive effects of SNHG16 on osteosarcoma tumor growth and metastasis were further supported by xenograft tumor growth assay. CONCLUSION: SNHG16 promoted migration, invasion and EMT of osteosarcoma by sponging miR-488 to release ITGA6.

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