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1.
Phys Chem Chem Phys ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39027937

RESUMO

Direct conversion of syngas into ethanol is an attractive process because of its short route and high-added value, but remains an enormous challenge due to the low selectivity caused by unclear active sites. Here, the Cu(111) supported N-modified graphene fragments C13-mNm/Cu(111) (m = 0-2) are demonstrated to be an efficient catalyst for fabricating ethanol from syngas and methanol. Our results suggest that the Cu-carbon interaction not only facilitates CO activation, but also significantly affects the adsorption stability of C2 intermediates and finally changes the fundamental reaction mechanism. The impeded hydrogenation performance of C13/Cu(111) due to the introduced Cu-carbon interaction is dramatically improved by N-doping. Multiple analyses reveal that the promoted electron transfer and the enhanced electron endowing ability of C13-mNm/Cu(111) (m = 1-2) to the co-adsorbed CH3CHxOH (x = 0-1) and H are deemed to be mainly responsible for the remarkable enhancement in hydrogenation ability. From the standpoint of the frontier molecular orbital, the decreased HOMO-LUMO gap and the increased overlap extent of HOMO and LUMO with the doping of N atoms also further verify the more facile hydrogenation reactions. Clearly, the Cu-carbon interaction through N-modification is of critical importance in ethanol formation. The final hydrogenation reaction during ethanol formation is deemed to be the rate-controlling step. The insights gained here could shed new light on the nature of Cu-carbon interaction in carbon material modified Cu-based catalysts for ethanol synthesis, which could be extended to design and modify other metal-carbon catalysts.

2.
J Med Chem ; 67(10): 8201-8224, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38736187

RESUMO

Although vaccination remains the prevalent prophylactic means for controlling Influenza A virus (IAV) infections, novel structural antivirus small-molecule drugs with new mechanisms of action for treating IAV are highly desirable. Herein, we describe a modular biomimetic strategy to expeditiously achieve a new class of macrocycles featuring oxime, which might target the hemagglutinin (HA)-mediated IAV entry into the host cells. SAR analysis revealed that the size and linker of the macrocycles play an important role in improving potency. Particularly, as a 14-membered macrocyclic oxime, 37 exhibited potent inhibitory activity against IAV H1N1 with an EC50 value of 23 nM and low cytotoxicity, which alleviated cytopathic effects and protected cell survival obviously after H1N1 infection. Furthermore, 37 showed significant synergistic activity with neuraminidase inhibitor oseltamivir in vitro.


Assuntos
Antivirais , Vírus da Influenza A Subtipo H1N1 , Compostos Macrocíclicos , Oximas , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Oximas/farmacologia , Oximas/química , Oximas/síntese química , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Relação Estrutura-Atividade , Humanos , Cães , Compostos Macrocíclicos/farmacologia , Compostos Macrocíclicos/química , Compostos Macrocíclicos/síntese química , Animais , Células Madin Darby de Rim Canino , Descoberta de Drogas , Biomimética , Oseltamivir/farmacologia , Oseltamivir/química
3.
Phytomedicine ; 130: 155764, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797030

RESUMO

BACKGROUND: Tanreqing injection (TRQ) has been employed in clinical practice as a treatment for dengue fever (DF). Nevertheless, the precise pharmacological mechanism underlying its efficacy remains elusive. METHOD: Network pharmacology, molecular docking, transcriptome sequencing, and experimental evaluation were employed to analyze and study the inhibitory potential of TRQ against dengue virus (DENV). RESULT: We found that TRQ inhibited the replication of DENV in human umbilical vein endothelial cells, Huh-7 cells, and Hep3B cells. In addition, TRQ prolonged the survival duration of AG129 mice infected with DF, decreased the viral load in serum and organs, and alleviated organ damage. Subsequently, ultra-high-performance liquid chromatography-tandem mass spectrometry analysis of TRQ was performed to identify 314 targets associated with 36 active compounds present in TRQ. Integration of multiple databases yielded 47 DF-related genes. Then, 15 hub targets of TRQ in DF were determined by calculating the network topology parameters (Degree). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that these pathways were primarily enriched in the processes of cytokine activation and leukocyte cross-endothelial migration, with significant enrichment of cell adhesion molecules. Molecular docking revealed favorable binding affinity between TRQ's key active compounds and the predicted hub targets. Transcriptome sequencing results showed TRQ's ability to restore the expression of vascular cell adhesion molecule-1 (VCAM-1) post-DENV infection. Finally, TRQ was found to modulate the immune status by regulating the nuclear factor kappa-B (NF-κB)- intercellular cell adhesion molecule-1 (ICAM-1)/VCAM-1 axis, as well as reduce immune cell alterations, inflammatory factor secretion, vascular permeability, and bleeding tendencies induced by DENV infection. CONCLUSION: Our research suggests that TRQ exerts therapeutic effects on DF by regulating the NF-κB-ICAM-1/VCAM-1 axis.


Assuntos
Antivirais , Vírus da Dengue , Dengue , Animais , Humanos , Camundongos , Antivirais/farmacologia , Dengue/tratamento farmacológico , Vírus da Dengue/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais da Veia Umbilical Humana , Molécula 1 de Adesão Intercelular/metabolismo , Simulação de Acoplamento Molecular , Farmacologia em Rede , NF-kappa B/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Replicação Viral/efeitos dos fármacos
4.
MedComm (2020) ; 5(4): e524, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38585232

RESUMO

Enteric IL-17RA deficiency leads to gut dysbiosis, consequently initiating the proliferation of tumors at remote locations. The deficiency or blockade of enteric IL-17RA induces the secretion of IL-17A by B cells and Th17 cells in response to microbial signals, resulting in a systemic elevation of IL-17A and fostering the growth of remote tumors. This figure was created with BioRender.com.

5.
Bioorg Chem ; 147: 107351, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593530

RESUMO

Eleven triterpenoid saponins, including five new compounds, which were named densiflorasides A - E (1 - 5), were isolated from aerial parts of Mussaenda densiflora (Rubiaceae). Their structures were elucidated based on spectroscopic and single-crystal X-ray diffraction analyses and chemical methods. All the isolated compounds and the aglycone heinsiagenin A were evaluated for their immunosuppressive and antiosteoclastogenic activities in vitro. Compounds 6 - 8 and heinsiagenin A inhibited osteoclastogenesis, with IC50 values ranging from 8.24 to 17.7 µM. Furthermore, compounds 3, 6 - 8, and heinsiagenin A significantly inhibited T-cell proliferation, with IC50 values ranging from 2.56 to 8.60 µM, and compounds 3 - 5 and 11 inhibited the proliferation of B lymphocytes, with IC50 values ranging from 1.29 to 8.49 µM. Further in vivo experiments indicated that heinsiagenin A could significantly attenuate IMQ-induced psoriasis and DSS-induced colitis in mice.


Assuntos
Proliferação de Células , Relação Dose-Resposta a Droga , Imunossupressores , Saponinas , Triterpenos , Saponinas/farmacologia , Saponinas/química , Saponinas/isolamento & purificação , Animais , Camundongos , Proliferação de Células/efeitos dos fármacos , Imunossupressores/farmacologia , Imunossupressores/química , Imunossupressores/isolamento & purificação , Relação Estrutura-Atividade , Triterpenos/química , Triterpenos/farmacologia , Triterpenos/isolamento & purificação , Estrutura Molecular , Linfócitos T/efeitos dos fármacos , Colite/tratamento farmacológico , Colite/induzido quimicamente , Masculino , Osteoclastos/efeitos dos fármacos
7.
Bioorg Chem ; 145: 107246, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428283

RESUMO

Phytochemical investigation of the stems of Celastrus monospermus Roxb enabled isolation and identification of fifteen new macrolide sesquiterpene pyridine alkaloids (1-15) along with five known analogues. Their structures were elucidated by comprehensive spectroscopic analysis (NMR, HRESIMS, IR, UV), chemical hydrolysis, and single crystal X-ray diffraction analysis. Bioassay of the abundant isolates revealed that seven compounds inhibited the proliferation of B lymphocytes with IC50 values ranging between 1.4 and 19.9 µM. Among them, celasmondine C (3) could significantly promote the apoptosis of activated B lymphocyte, especially late-stage apoptosis. Besides, compounds 3, 16, and 20 exhibited potent suppression of osteoclast formation at a concentration of 1.0 µM. This investigation enriched the chemical diversity of macrolide sesquiterpene pyridine alkaloids, and supported evidence for the development of new immunosuppressive and anti-osteoclastogenesis agents.


Assuntos
Alcaloides , Celastrus , Sesquiterpenos , Celastrus/química , Macrolídeos , Estrutura Molecular , Piridinas/farmacologia , Piridinas/química , Alcaloides/farmacologia , Alcaloides/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química
8.
Phytochemistry ; 221: 114038, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38395211

RESUMO

Cephalotanes are a rare class of diterpenoids occurring exclusively in Cephalotaxus plants. The intriguing structures and promising biological activities for this unique compound class prompt us to investigate C. fortunei var. alpina and C. sinensis, leading to the isolation of six undescribed cephalotane-type diterpenoids and/or norditerpenoids, ceforloids A-F (1-6). Their structures were elucidated by comprehensive analysis of spectroscopic data, including ECD and single-crystal X-ray diffraction studies, as well as quantum chemical calculations. Compound 1 possesses an unprecedented norditerpenoid skeleton featuring an unusual acetophenone moiety, and originated putatively from a disparate biogenetic pathway. Compounds 4 and 5 incorporate a unique 12,13-p-hydroxybenzylidene acetal motif. Compound 6 is a rare cephalotane-type diterpenoid glycoside. Immunosuppressive assays showed that compounds 2 and 6 exhibited mild suppressive activity against the activated T and B lymphocytes proliferation. These findings not only expanded the structural diversity of this small group of diterpenoids, but also explored their potential as novel structures for the development of immunosuppressive agents.


Assuntos
Cephalotaxus , Diterpenos , Estrutura Molecular , Cephalotaxus/química , Diterpenos/farmacologia , Diterpenos/química , Imunossupressores , Cristalografia por Raios X
9.
RSC Adv ; 14(5): 3158-3162, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38249667

RESUMO

A simple and efficient synthetic approach to 2-amino-9H-chromeno[2,3-d]thiazol-9-ones via copper-promoted cascade reactions was developed. The reaction employed easily available 2-amino-3-iodochromones and amines as substrates and the targeting tricyclic compounds could be obtained with moderate to good yields. Even more important, several synthesized compounds exhibited potent anti-inflammatory activities, which suggested that this protocol may provide valuable hits for drug development in the future.

10.
Nanomaterials (Basel) ; 14(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38251104

RESUMO

The investigation of the features of laser control over the state of nanoscale objects in solid materials is an urgent task of condensed matter physics. We experimentally established the potential for the simultaneous enhancement of hardness and resistance to surface cracking in a titanium alloy due to selective laser irradiation. The regularities of selective heating near nanopores and the influence of the nanopore system on the features of isotherm propagation have been revealed. A physical model is proposed for the healing of nanopores situated in the surface layer of the sample. According to this model and as a result of laser irradiation and laser plasma, a brief transition of the material surface to extreme conditions is initiated.

11.
Acta Pharmacol Sin ; 45(1): 166-179, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37605050

RESUMO

Dry eye disease (DED) is a prevalent ocular disorder with a multifactorial etiology. The pre-angiogenic and pre-inflammatory milieu of the ocular surface plays a critical role in its pathogenesis. DZ2002 is a reversible type III S-adenosyl-L-homocysteine hydrolase (SAHH) inhibitor, which has shown excellent anti-inflammatory and immunosuppressive activities in vivo and in vitro. In this study, we evaluated the therapeutic potential of DZ2002 in rodent models of DED. SCOP-induced dry eye models were established in female rats and mice, while BAC-induced dry eye model was established in female rats. DZ2002 was administered as eye drops (0.25%, 1%) four times daily (20 µL per eye) for 7 or 14 consecutive days. We showed that topical application of DZ2002 concentration-dependently reduced corneal neovascularization and corneal opacity, as well as alleviated conjunctival irritation in both DED models. Furthermore, we observed that DZ2002 treatment decreased the expression of genes associated with angiogenesis and the levels of inflammation in the cornea and conjunctiva. Moreover, DZ2002 treatment in the BAC-induced DED model abolished the activation of the STAT3-PI3K-Akt-NF-κB pathways in corneal tissues. We also found that DZ2002 significantly inhibited the proliferation, migration, and tube formation of human umbilical endothelial cells (HUVECs) while downregulating the activation of the STAT3-PI3K-Akt-NF-κB pathway. These results suggest that DZ2002 exerts a therapeutic effect on corneal angiogenesis in DED, potentially by preventing the upregulation of the STAT3-PI3K-Akt-NF-κB pathways. Collectively, DZ2002 is a promising candidate for ophthalmic therapy, particularly in treating DED.


Assuntos
Neovascularização da Córnea , Síndromes do Olho Seco , Ratos , Humanos , Camundongos , Animais , Feminino , Neovascularização da Córnea/tratamento farmacológico , Neovascularização da Córnea/metabolismo , Neovascularização da Córnea/patologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Roedores/metabolismo , Células Endoteliais/metabolismo , Angiogênese , Inflamação/tratamento farmacológico , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/induzido quimicamente , Fator de Transcrição STAT3/metabolismo
12.
Biomed Pharmacother ; 170: 115975, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070246

RESUMO

Osteoarthritis (OA) is characterized by gradual articular cartilage degradation, accompanied by persistent low-grade joint inflammation, correlating with radiographic and pain-related progression. The latent therapeutic potential of DZ2002, a reversible inhibitor of S-adenosyl-L-homocysteine hydrolase (SAHH), holds promise for OA intervention. This study endeavored to examine the therapeutic efficacy of DZ2002 within the milieu of OA. The cytotoxicity of DZ2002 was evaluated using the MTT assay on bone marrow-derived macrophages. The inhibitory impact of DZ2002 during the process of osteoclastogenesis was assessed using TRAP staining, analysis of bone resorption pits, and F-actin ring formation. Mechanistic insights were derived from qPCR and Western blot analyses. Through the intra-articular injection of monosodium iodoacetate (MIA), an experimental rat model of OA was successfully instituted. This was subsequently accompanied by a series of assessments including Von Frey filament testing, analysis of weight-bearing behaviors, and micro-CT imaging, all aimed at assessing the effectiveness of DZ2002. The findings emphasized the effectiveness of DZ2002 in mitigating osteoclastogenesis induced by M-CSF/RANKL, evident through a reduction in TRAP-positive OCs and bone resorption. Moreover, DZ2002 modulated bone resorption-associated gene and protein expression (CTSK, CTR, Integrin ß3) via the MEK/ERK pathway. Encouragingly, DZ2002 also alleviates MIA-induced pain, cartilage degradation, and bone loss. In conclusion, DZ2002 emerges as a potential therapeutic contender for OA, as evidenced by its capacity to hinder in vitro M-CSF/RANKL-induced osteoclastogenesis and mitigate in vivo osteoarthritis progression. This newfound perspective provides substantial support for considering DZ2002 as a compelling agent for osteoarthritis intervention.


Assuntos
Reabsorção Óssea , Cartilagem Articular , Osteoartrite , Ratos , Animais , Ácido Iodoacético/efeitos adversos , Ácido Iodoacético/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Sistema de Sinalização das MAP Quinases , Osteoartrite/induzido quimicamente , Osteoartrite/tratamento farmacológico , Osteoartrite/metabolismo , Dor/tratamento farmacológico , Cartilagem Articular/metabolismo , Reabsorção Óssea/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Modelos Animais de Doenças
13.
Antiviral Res ; 221: 105763, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008192

RESUMO

Development of new anti-hepatitis B virus (HBV) drugs that target viral capsid assembly is a very active research field. We identify a novel phthalazinone derivative, compound 5832, as a potent HBV inhibitor. In this study, we intend to elaborate the antiviral effect and mechanism of 5832 against HBV in vitro and in vivo. Compound 5832 treatment induces the formation of genome-free empty capsid by interfering with the core protein assembly domain, which significantly decreases the extracellular and intracellular HBV DNA. In the AAV-HBV transduced mouse model, 5832 suppresses serum HBV DNA after 4-week treatment, and decreases HBsAg and HBeAg levels. 5832 treatment also reduces intrahepatic HBV RNA, DNA and HBcAg levels. During the follow-up period after treatment withdrawal, serum antigen levels demonstrated no increase. We demonstrate 5832 treatment could active apoptotic signaling by elevating the expression of death receptor 5 (DR5), which participated in corresponding HBcAg-positive hepatocyte eradication. Phthalazinone derivative 5832 may serve as a promising anti-HBV drug candidate to improve the treatment options for chronic HBV infection.


Assuntos
Hepatite B Crônica , Hepatite B , Camundongos , Animais , Vírus da Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B/metabolismo , Capsídeo , DNA Viral/genética , Proteínas do Capsídeo/metabolismo , Antígenos de Superfície da Hepatite B , Antivirais/uso terapêutico
14.
Innovation (Camb) ; 4(6): 100524, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38028132
15.
Immun Inflamm Dis ; 11(11): e1069, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38018571

RESUMO

BACKGROUND: Ulcerative colitis (UC), a chronic inflammatory disease, is caused by abnormal immune system reactions resulting in inflammation and ulcers in the large intestine. Phillygenin (PHI) is a natural compound found in Forsythia suspensa (Thunb.) Vahl, which is known for its antipyretic, anti-inflammatory, antiobesity, and other biological activities. However, the therapeutic role and molecular mechanisms of PHI on UC are still insufficiently researched. METHODS: In this study, dextran sulfate sodium (DSS) and 2.5% 2,4,6-trinitro-Benzenesulfonic acid (TNBS)-induced acute UC were used to investigate the therapeutic effects of PHI. We evaluated the effects of PHI on disease activity index (DAI), body weight, mortality, intestinal mucosal barrier, cytokine secretion, and macrophage infiltration into colon tissue using various techniques such as flow cytometry, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), RT-qPCR, and Western blot analysis. RESULTS: Our findings revealed that PHI has therapeutic properties in UC treatment. PHI was able to maintain body weight, reduce DAI and mortality, restore the intestinal mucosal barrier, and inhibit cytokine secretion. Flow cytometry assay and immunofluorescence indicated that PHI reduces macrophage infiltration into colon tissue. Mechanistically, PHI may exert anti-inflammatory effects by downregulating the TLR4/MyD88/NF-κB pathway and inhibiting the activation of NLRP3 inflammasome. CONCLUSION: In conclusion, PHI possesses significant anti-inflammatory properties and is expected to be a potential drug for UC treatment. Our study delves into the underlying mechanisms of PHI therapy and highlights the potential for further research in developing PHI-based treatments for UC.


Assuntos
Colite Ulcerativa , Forsythia , NF-kappa B/metabolismo , Colite Ulcerativa/tratamento farmacológico , Inflamassomos/efeitos adversos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Fator 88 de Diferenciação Mieloide/farmacologia , Receptor 4 Toll-Like/metabolismo , Forsythia/metabolismo , Transdução de Sinais , Anti-Inflamatórios/efeitos adversos , Citocinas/metabolismo , Peso Corporal
16.
Phytomedicine ; 119: 154977, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37506573

RESUMO

BACKGROUND: Dengue virus (DENV) is a major public health threat. However, there are no specific therapeutic drugs for DENV. Many Chinese heat-cleaning formulas, such as Liang-Ge-San (LGS), have been frequently used in the virus-induced diseases. The antiviral effect of LGS has not been reported yet. PURPOSE: In this study, the effect of LGS on the inhibition of dengue virus serotype 2 (DENV-2) was investigated and the relevant mechanism was explored. METHODS: High-performance liquid chromatography was applied to analyze the chemical characterization of LGS. The in vitro antiviral activities of LGS against DENV-2 were evaluated by time-of-drug-addition assay. The binding of heat shock protein 70 (Hsp70) and envelope (E) protein or caveolin1 (Cav1) were analyzed by immunofluorescence and immunoprecipitation assays. Then the role of Cav1 in the anti-DENV-2 effects of LGS was further examined. DENV-2 infected Institute of Cancer Research suckling mice (n = 10) and AG129 mice (n = 8) were used to examine the protective effects of LGS. RESULTS: It was found that geniposide, liquiritin, forsythenside A, forsythin, baicalin, baicalein, rhein, and emodin maybe the characteristic components of LGS. LGS inhibited the early stage of DENV-2 infection, decreased the expression levels of viral E and non-structural protein 1 (NS1) proteins. LGS also reduced E protein and Hsp70 binding and attenuated the translocation of Hsp70 from cytoplasm to the cell membrane. Moreover, LGS decreased the binding of Hsp70 to Cav1. Further study showed that the overexpression of Cav1 reversed LGS-mediated E protein and Hsp70 inhibition in the plasma membrane. In the in vivo study, LGS was highly effective in prolonging the survival time, reducing viral loads. CONCLUSION: This work demonstrates for the first time that LGS exerts anti-DENV-2 activity in vitro and in vivo. LGS decreases DENV-2-stimulated cytoplasmic Hsp70 translocation into the plasma membrane by Cav1 inhibition, thereby inhibiting the early stage of virus infection. These findings indicate that LGS may be a candidate for the treatment of DENV.


Assuntos
Vírus da Dengue , Dengue , Animais , Camundongos , Dengue/tratamento farmacológico , Proteínas de Choque Térmico HSP70 , Sorogrupo , Membrana Celular , Antivirais/farmacologia , Antivirais/uso terapêutico , Citoplasma/metabolismo
18.
Eur J Med Chem ; 257: 115485, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37229833

RESUMO

CAMs were disclosed to alter cccDNA levels with sustained hepatitis B surface antigen (HBsAg) loss or seroconversion in preclinical investigation. Here, we report the discovery of a prodrug Yhhu6669 as CAMs based on the intestinal peptide transporter. This compound exhibited the promising anti-HBV activity with sustained suppression of HBV DNA, as well as HBsAg and HBeAg in the AAV HBV mouse model by oral treatment for 7 weeks and maintained for a further 8 weeks following drug withdraw. Our results show an alternative possibility for a functional cure by specific CAMs and provide the basis for the further mechanism study.


Assuntos
Hepatite B Crônica , Pró-Fármacos , Animais , Camundongos , Antígenos de Superfície da Hepatite B/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Antígenos E da Hepatite B , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Vírus da Hepatite B/genética , Capsídeo , Antivirais/farmacologia , Antivirais/uso terapêutico , Proteínas do Capsídeo , DNA Viral
20.
PLoS One ; 18(4): e0284140, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37043500

RESUMO

Gas drainage materials are one critical aspect of preventing coal mine gas explosions. Here, a novel dual-liquid gas sealing material was developed to improve gas extraction. The mechanical properties and hydration mechanism of the proposed material were determined. The novel dual-liquid gas sealing material's performance was verified experimentally and with field testing, with practical application explored in the YunGaiShan 2 coal mine. The results showed that the main factor responsible for gas drainage leakage was the poor sealing effect of the sealing materials on the cracks around the borehole. The novel dual-liquid gas sealing material reduced damage to the rock surrounding the borehole and significantly improved the gas drainage performance. The initial and final setting times of the novel dual-liquid material were shown to be controllable, and the slurry exhibited good fluidity, with a 28-day uniaxial compressive strength of 11.06 MPa. The analysis of the microscopic hydration mechanism showed that the production of ettringite (AFt) in the dual-liquid material increased significantly, forming a denser network interlace that functioned as a network skeleton, improving the compressive strength of the material and achieving the characteristics of plastic deformation. Field-based analysis was performed to verify the practical applicability of the proposed material, showing that the gas drainage concentration increased by 200.5% compared to the original sealing material. Moreover, the average gas drainage negative pressure increased from 7.8 kPa (using the conventional sealing technique) to 16.6 kPa using the proposed material. Overall, the proposed materials are suitable for sealing materials for effective gas drainage performance and can help control gas disasters.


Assuntos
Carvão Mineral , Mineração
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