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1.
Molecules ; 29(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542825

RESUMO

Roasting is an important step in the pretreatment of biomass upgrading. Roasting can improve the fuel quality of biomass, reduce the O/C and H/C ratios in the biomass, and provide the biomass with a fuel quality comparable to that of lignite. Therefore, studying the structure and component evolution laws during biomass roasting treatment is important for the rational and efficient utilization of biomass. When the roasting temperature is 200-300 °C, the cellulose and hemicellulose in the biomass undergo a depolymerization reaction, releasing many monocyclic aromatic hydrocarbons with high reactivity. The proportion of monocyclic aromatic hydrocarbons in biomass roasting products can be effectively regulated by controlling the reaction temperature, residence time, catalyst, baking atmosphere, and other factors in the biomass roasting process. This paper focuses on the dissociation law of organic components in the pretreatment process of biomass roasting.


Assuntos
Temperatura Alta , Hidrocarbonetos Aromáticos , Biomassa , Hidrocarbonetos Aromáticos/química , Temperatura , Celulose , Hidrocarbonetos
2.
J Proteomics ; 206: 103435, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-31279926

RESUMO

The neurotoxins of venomous scorpion act on ion channels. Whether these neurotoxins are retained in processed Buthus martensii Karsch scorpions used in traditional Chinese medicine materials is unknown. Comprehensive mass spectrometry-based proteomic characterization of functionally active toxins in the processed medicinal scorpion material revealed 22 full-length and 44 truncated thermostable potassium channel-modulatory toxins that preserved six conserved cysteine residues capable of forming the three disulfide bonds necessary for toxicity. Additionally, a broad spectrum of degraded toxin fragments was found, indicating their relative thermal instability which enabled toxicity reduction. Furthermore, the suppression of interleukin-2 (IL-2) production in Jurkat cells and the reduced delayed-type hypersensitivity (DTH) response demonstrated that the extracts have immunoregulatory activity both in vitro and in vivo. Our work describes the first "map" of functionally active scorpion toxins in processed scorpion medicinal material, which is helpful to unveil the pharmaceutical basis of the processed scorpion medicinal material in traditional Chinese medicine. BIOLOGICAL SIGNIFICANCE: Scorpions have been used as medicinal materials in China for more than one thousand years. This is an example of the well-known "Combat poison with poison" strategy common to traditional Chinese medicine. In the past 30 years, extensive investigations of Chinese scorpions have indicated that the neurotoxins in the scorpion venom are the main toxic components and they target various ion channels in cell membranes. However, whether these neurotoxins are retained in processed Buthus martensii Karsch scorpions used for traditional Chinese medicine remains unknown. Our study described the thermal stability and instability of potassium channel-modulatory neurotoxins in processed scorpions and helps to understand the pharmaceutical basis underling the strategy of "combat poison with poison to cure diseases".


Assuntos
Medicina Tradicional Chinesa , Neurotoxinas/análise , Bloqueadores dos Canais de Potássio/análise , Proteoma/análise , Venenos de Escorpião/análise , Animais , Estabilidade de Medicamentos , Feminino , Células HEK293 , Humanos , Células Jurkat , Neurotoxinas/metabolismo , Peptídeos/análise , Peptídeos/metabolismo , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Preparações Farmacêuticas/metabolismo , Bloqueadores dos Canais de Potássio/isolamento & purificação , Bloqueadores dos Canais de Potássio/metabolismo , Canais de Potássio/metabolismo , Estabilidade Proteica , Proteoma/metabolismo , Proteômica/métodos , Ratos , Ratos Endogâmicos Lew , Venenos de Escorpião/química , Venenos de Escorpião/metabolismo , Escorpiões/química , Escorpiões/metabolismo , Temperatura
3.
Virol Sin ; 34(5): 549-562, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31134586

RESUMO

Dengue virus (DENV) infection is a worldwide public health threat. To date, the knowledge about the pathogenesis and progression of DENV infection is still limited. Combining global profiling based on proteomic analysis together with functional verification analysis is a powerful strategy to investigate the interplay between the virus and host cells. In the present study, quantitative proteomics has been applied to evaluate host responses (as indicated by altered proteins and modifications) in human cells (using K562 cell line) upon DENV-2 infection, as DENV-2 spreads most widely among all DENV serotypes. Comparative analysis was performed to define differentially expressed proteins in the infected cells compared to the mock-control, and it revealed critical pathogen-induced changes covering a broad spectrum of host cellular compartments and processes. We also discovered more dramatic changes (> 20%, 160 regulated phosphoproteins) in protein phosphorylation compared to protein expression (14%, 321 regulated proteins). Most of these proteins/phosphoproteins were involved in transcription regulation, RNA splicing and processing, immune system, cellular response to stimulus, and macromolecule biosynthesis. Western blot analysis was also performed to confirm the proteomic data. Potential roles of these altered proteins were discussed. The present study provides valuable large-scale protein-related information for elucidating the functional emphasis of host cell proteins and their post-translational modifications in virus infection, and also provides insight and protein evidence for understanding the general pathogenesis and pathology of DENV.


Assuntos
Vírus da Dengue/patogenicidade , Interações Hospedeiro-Patógeno/genética , Proteômica , Replicação Viral , Biologia Computacional , Vírus da Dengue/fisiologia , Humanos , Células K562 , Fosforilação , Processamento de Proteína Pós-Traducional
4.
Clin Epigenetics ; 11(1): 48, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30867030

RESUMO

BACKGROUND: Activation of transcription enhancers, especially super-enhancers, is one of the critical epigenetic features of tumorigenesis. However, very few studies have systematically identified the enhancers specific in cancer tissues. METHODS: Here, we studied the change of histone modifications in MMTV-PyVT breast cancer model, combining mass spectrometry-based proteomics and ChIP-seq-based epigenomics approaches. Some of the proteomic results were confirmed with western blotting and IHC staining. An inhibitor of H3K27ac was applied to study its effect on cancer development. RESULTS: H3K27ac and H4K8ac are elevated in cancer, which was confirmed in patient tissue chips. ChIP-seq revealed that H4K8ac is co-localized with H3K27ac on chromatin, especially on distal enhancers. Epigenomic studies further identified a subgroup of super-enhancers marked by H3K4me3 peaks in the intergenic regions. The H3K4me3-enriched regions enhancers are associated with higher level of H3K27ac and H4K8ac compared with the average level of conventional super-enhancers and are associated with higher transcription level of their adjacent genes. We identified 148 H3K4me3-enriched super-enhancers with higher gene expression in tumor, which may be critical for breast cancer. One inhibitor for p300 and H3K27ac, C646, repressed tumor formation probably through inhibiting Vegfa and other genes. CONCLUSIONS: Taken together, our work identifies novel regulators and provides important resource to the genome-wide enhancer studies in breast cancer and raises the possibility of cancer treatment through modulating enhancer activity.


Assuntos
Neoplasias da Mama/patologia , Elementos Facilitadores Genéticos , Histonas/genética , Histonas/metabolismo , Neoplasias Mamárias Experimentais/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Epigênese Genética , Epigenômica , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Código das Histonas , Humanos , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Proteômica , Ativação Transcricional , Regulação para Cima
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