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1.
Bioresour Technol ; 394: 130295, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184085

RESUMO

This study explored bagasse's energy potential grown using treated industrial wastewater through various analyses, experimental, kinetic, thermodynamic, and machine learning boosted regression tree methods. Thermogravimetry was employed to determine thermal degradation characteristics, varying the heating rate from 10 to 30 °C/min. The primary pyrolysis products from bagasse are H2, CH4, H2O, CO2, and hydrocarbons. Kinetic parameters were estimated using three model-free methods, yielding activation energies of approximately 245.98 kJ mol-1, 247.58 kJ mol-1, and 244.69 kJ mol-1. Thermodynamic parameters demonstrated the feasibility and reactivity of pyrolysis with ΔH ≈ 240.72 kJ mol-1, ΔG ≈ 162.87 kJ mol-1, and ΔS ≈ 165.35 J mol-1 K-1. The distribution of activation energy was analyzed using the multiple distributed activation energy model. Lastly, boosted regression trees predicted thermal degradation successfully, with an R2 of 0.9943. Therefore, bagasse's potential as an eco-friendly alternative to fossil fuels promotes waste utilization and carbon footprint reduction.


Assuntos
Celulose , Pirólise , Termodinâmica , Cinética , Termogravimetria
2.
IEEE Trans Med Imaging ; 43(1): 76-95, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37379176

RESUMO

Existing self-supervised medical image segmentation usually encounters the domain shift problem (i.e., the input distribution of pre-training is different from that of fine-tuning) and/or the multimodality problem (i.e., it is based on single-modal data only and cannot utilize the fruitful multimodal information of medical images). To solve these problems, in this work, we propose multimodal contrastive domain sharing (Multi-ConDoS) generative adversarial networks to achieve effective multimodal contrastive self-supervised medical image segmentation. Compared to the existing self-supervised approaches, Multi-ConDoS has the following three advantages: (i) it utilizes multimodal medical images to learn more comprehensive object features via multimodal contrastive learning; (ii) domain translation is achieved by integrating the cyclic learning strategy of CycleGAN and the cross-domain translation loss of Pix2Pix; (iii) novel domain sharing layers are introduced to learn not only domain-specific but also domain-sharing information from the multimodal medical images. Extensive experiments on two publicly multimodal medical image segmentation datasets show that, with only 5% (resp., 10%) of labeled data, Multi-ConDoS not only greatly outperforms the state-of-the-art self-supervised and semi-supervised medical image segmentation baselines with the same ratio of labeled data, but also achieves similar (sometimes even better) performances as fully supervised segmentation methods with 50% (resp., 100%) of labeled data, which thus proves that our work can achieve superior segmentation performances with very low labeling workload. Furthermore, ablation studies prove that the above three improvements are all effective and essential for Multi-ConDoS to achieve this very superior performance.


Assuntos
Processamento de Imagem Assistida por Computador , Taxa Respiratória , Aprendizado de Máquina Supervisionado
3.
Neurol Res ; 45(4): 319-333, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36417294

RESUMO

OBJECTIVES: This study aims to explore the role of lncRNA TMPO-AS1 in ischemic stroke and corresponding mechanism. METHODS: Adult male C57BL/6 J mice were subjected to a middle cerebral artery occlusion (MCAO) model of ischemic stroke, then TMPO-AS1 shRNA lentivirus were injected into ipsilateral striatum of mice. The neurological score and cerebral infarction volume were evaluatedHypoxia/glucose deprivation/reoxygenation (OGD/R)-induced BV2 cells were transfected with TMPO-AS1 shRNA (sh-TMPO-AS1) or together with pcDNA-INPP5D, as well as transfected with sh-PU.1 or together with pcDNA-INPP5D, then TMPO-AS1 level, the expression of PU.1 and INPP5D proteins, the secretion of inflammatory factors (TNF-α, IL-6 and IL-1ß), the levels of iNOS, CD68,Arg1 and CD206 mRNA were detected. RIP and PNA-pull down assays were used to detect the binding of TMPO-AS1 and PU.1, luciferase reporter gene and chromatin immunoprecipitation (ChIP) assays were used to detect the binding activity of PU.1 and INPP5D. RESULTS: TMPO-AS1 level was increased in peripheral blood of ischemic stroke patients , brain tissues of MCAO/R model mice and OGD/R-induced BV2 cells. TMPO-AS1 interference inhibited the inflammation of OGD/R-induced BV2 cells. TMPO-AS1 also enhanced the nuclear accumulation of PU.1 by binding to the transcription factor PU.1, and promoted the transcriptional activation of INPP5D. The anti-inflammatory effects of TMPO-AS1 interference were reversed by INPP5D overexpression. In addition, TMPO-AS1 interference improved the infarct volume of MCAO mice, and improved sensorimotor and cognitive functions. CONCLUSION: INPP5D underexpression mediated by TMPO-AS1-PU.1 complex alleviated neuroinflammation after ischemic stroke.


Assuntos
AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Animais , Masculino , Camundongos , Infarto da Artéria Cerebral Média/metabolismo , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Doenças Neuroinflamatórias , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , RNA Interferente Pequeno , Acidente Vascular Cerebral/metabolismo
4.
Eur J Neurosci ; 55(7): 1709-1723, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35239205

RESUMO

Microglia are the static resident cells possessing the phagocytic properties in the central nervous system (CNS). In many relevant studies, the immortalized murine microglial cell line BV2 has been used as a tool in primary microglia (PM) relevant studies. Microglia participate in neuroinflammation by converting into M1- and M2-like phenotypes. In this study, we established M1- and M2-like phenotype response models by exposing PM and BV2 cells to lipopolysaccharides (LPS) and interlukin-4 (IL-4), respectively, and discovered the proteomic differences between the two types of microglia. It turned out that the BV2 cell responses to LPS and IL-4 were narrower and weaker than that of PM. In addition, irradiation, which has been shown to activate microglia and induces neuroinflammation, was also used as a treatment in this study. The results showed that BV2 cells have stronger capacity of DNA damage repair. Besides, irradiation had a negative effect on the regulation of KEGG pathways such as proteasome, ribosome, oxidative phosphorylation and TCA cycle in both cells. Furthermore, the KEGG pathways including cell cycle and DNA replication (significantly downregulated), and antigen processing and presentation and FC γ R mediated phagocytosis (significantly up-regulated) were only found in irradiated PM. These data demonstrate that PM is more fragile to irradiation. Results in this study indicate that BV2 cells only partially model PM, and thus, using BV2 in microglia related studies should be carefully considered.


Assuntos
Lipopolissacarídeos , Microglia , Animais , Linhagem Celular , Interleucina-4/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , Proteômica
5.
J Biomed Inform ; 120: 103834, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34119692

RESUMO

Medicine instructions usually contain rich medical relations, and extracting them is very helpful for many downstream tasks such as medicine knowledge graph construction and medicine side-effect prediction. Existing relation extraction (RE) methods usually predict relations between entities from their contexts and do not consider medical knowledge. However, understanding a part of medical relations may need some expert knowledge in the medical field, making it challenging for existing methods to achieve satisfying performances of medical RE. In this paper, we propose a knowledge-enhanced framework for medical RE, which can exploit medical knowledge of medicines to better conduct medical RE on Chinese medicine instructions. We first propose a BERT-CNN-LSTM based framework for text modeling and learn representations of characters from their contexts. Then we learn representations of each entity by aggregating representations of their characters. Besides, we propose a CNN-LSTM based framework for entity modeling and learn entity representations from their relatedness. In addition, there are usually many different instructions for the same medicine, which usually share general knowledge on this medicine. Thus, to obtain medical knowledge of medicines, we annotate relations on a randomly-sampled instruction of each medicine. Then we build knowledge embeddings to represent potential relations between entities from knowledge of medicines. Finally, we use an MLP network to predict relations between entities from their representations and knowledge embeddings. Extensive experiments on a real-world dataset show that our method can significantly outperform existing methods.


Assuntos
Registros Eletrônicos de Saúde , Envio de Mensagens de Texto , Conhecimento , Medicina Tradicional Chinesa
6.
Bioresour Technol ; 322: 124545, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341710

RESUMO

The present study was focused on evaluating the bioenergy potential of waste biomass of desert plant Calotropis procera. The biomass was pyrolyzed at four heating rates including 10 °Cmin-1, 20 °Cmin-1, 40 °Cmin-1, and 80 °Cmin-1. The pyrolysis reaction kinetics and thermodynamics parameters were assessed using isoconversional models namely Kissenger-Akahira-Sunose, Flynn-Wall-Ozawa, and Starink. Major pyrolysis reaction occurred between 200 and 450 °C at the conversion points (α) ranging from 0.2 to 0.6 while their corresponding reaction parameters including activation energy, enthalpy change, Gibb's free energy and pre-exponential factors were ranged from 165 to 207 kJ mol-1, 169-200 kJ mol-1, 90-42 kJ mol-1, and 1018-1026 s-1, respectively. The narrow range of pre-exponential factors indicated a uniform pyrolysis, while lower differences between enthalpy change and activation energies indicated that reactions were thermodynamically favorable. The evolved gases were dominated by propanoic acid, 3-hydroxy-, hydrazide, hydrazinecarboxamide and carbohydrazide followed by amines/amides, alcohols, acids, aldehydes/ketones, and esters.


Assuntos
Calotropis , Pirólise , Biomassa , Cinética , Termogravimetria
7.
Food Sci Nutr ; 8(1): 322-331, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31993158

RESUMO

In this study, the adsorption/desorption characteristics of rapeseed meal polysaccharides extract on four resins (HP-20, D3520, XAD-16, and AB-8) were evaluated. The results indicated that HP-20 resin had the best purification effect. Based on static adsorption test, the kinetics and isotherms of the four resins for protein and polysaccharide were investigated. The adsorption test showed that the pseudo-second-order kinetics model and the Freundlich isotherm model were more suitable for explanation of the adsorption process for protein and polysaccharide. Static desorption test showed that the highest protein desorption ratios of HP-20, D3520, and AB-8 resins could be obtained with 60% ethanol solution as eluate, and the highest protein desorption ratios of XAD-16 resin could be obtained with 40% ethanol solution as eluate. Dynamic adsorption/desorption tests of HP-20 resin showed that the deproteinization ratio was 91% and the polysaccharide recovery ratio was 62% when the treatment amount was 1.5 BV. Compared with three traditional methods, HP-20 resin adsorption method that the deproteinization ratio was 82% was more potent than the three traditional methods for purifying polysaccharides from rapeseed meal. In addition, UV/vis spectroscopy showed that most of the protein was absorbed by resins, and FT-IR spectroscopy indicated that the purity of the polysaccharide after purification was improved. Rapeseed meal polysaccharides could be effectively deproteinized using HP-20 resin, and it was suitable for purifying polysaccharides from rapeseed meal.

8.
J Hazard Mater ; 384: 121428, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31699486

RESUMO

Three types of mosquito-repellent incenses including disc, electric liquid and electric mat, were selected to investigate the emission of volatile organic compounds in the respiratory zone during the burning. VOCs were analyzed by GC-MS. Results showed that the average concentration of TVOCs released by using the disc, electric liquid and electric mat mosquito repellent incense types were 7.760 ±â€¯4.724, 3.122 ±â€¯0.866 and 1.192 ±â€¯0.062 mg/m3, respectively. The TVOCs pollution level produced during the burning of different mosquito-repellent incense types was ranked in the order: disc > electric liquid > electric mat. The concentration of TVOCs produced by Q-liquid, L-liquid, Q-disc and L-disc mosquito-repellent incense types could cause discomfort to the human body. Other types of mosquito-repellent incense induced multiple synergistic effects on human response. About 230 kinds of VOCs including 14 types of VOCs, were found in the smoke of mosquito-repellent incense. The number and content of alkanes was the highest, followed by aromatic hydrocarbons and esters. The level of non-carcinogenic health risk presented by exposure to BTEX (toluene, xylene and ethylbenzene) was acceptable. The chronic daily intake of VOCs decreased with age for both males and females, with male exposure being higher than that of the female, except for children.


Assuntos
Poluentes Atmosféricos , Derivados de Benzeno , Exposição por Inalação , Repelentes de Insetos , Compostos Orgânicos Voláteis , Adolescente , Adulto , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Animais , Derivados de Benzeno/análise , Derivados de Benzeno/toxicidade , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Repelentes de Insetos/análise , Repelentes de Insetos/toxicidade , Masculino , Pessoa de Meia-Idade , Controle de Mosquitos , Medição de Risco , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/toxicidade , Adulto Jovem
9.
PLoS One ; 8(7): e69452, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894482

RESUMO

BACKGROUND/AIMS: Septic cardiomyopathy is a severe condition that remains a challenge for clinical management. This study investigated whether the natural polyphenolic compound resveratrol could be used as a prophylactic treatment to alleviate sepsis-related myocardial injury; the underlying molecular mechanisms were deciphered by both in vitro and in vivo experiments. METHODS: A mouse model of endotoxin-induced cardiomyopathy was developed by intraperitoneal injection of LPS, and resveratrol was administered prophylatically to the animals. Serum LDH and CK activities were measured to detect myocardial injury, and echocardiography was performed to monitor cardiac structure and function. Various cytokines/chemokines and the Nrf2 antioxidant defense system were examined in the heart tissue. The effects of resveratrol on LPS-induced Nrf2 activation, ROS generation, and apoptotic cell death were further investigated in cultured primary human cardiomyocytes. An Nrf2 specific siRNA was used to define its role in resveratrol-mediated cardiomyocyte protective effect. RESULTS: Resveratrol pretreatment significantly attenuated LPS-induced myocardial injury in mice, which was associated with suppressed proinflammatory cytokine production and enhanced Nrf2 activation in the heart. In cultured primary human cardiomyocytes, resveratrol activated Nrf2, inhibited LPS-induced ROS generation, and effectively protected the cells from LPS-induced apoptotic cell death. Knockdown of Nrf2 abrogated resveratrol-mediated protection of the cells from LPS-induced cell death. CONCLUSION: Resveratrol effectively alleviates endotoxin-induced cardiac toxicity through mechanisms that involve the Nrf2 antioxidant defense pathway. Our data suggest that resveratrol might be developed as a useful prophylactic management for septic cardiomyopathy.


Assuntos
Cardiotônicos/farmacologia , Endotoxinas/toxicidade , Coração/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estilbenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Citocinas/biossíntese , Técnicas de Silenciamento de Genes , Humanos , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/deficiência , Fator 2 Relacionado a NF-E2/genética , Espécies Reativas de Oxigênio/metabolismo , Resveratrol
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