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1.
Artigo em Inglês | MEDLINE | ID: mdl-34137266

RESUMO

Photothermal/electrothermal advanced functional form-stable phase change materials (FSPCMs) can efficiently make use of solar energy and electrical energy by using supporting materials to encapsulate phase change materials. Herein, a novel low-cost integrated supporting material, denoted PDVB-12/PPy NTs, is quickly constructed via wrapping the polypyrrole (PPy) on the mesoporous polydivinylbenzene nanotubes (PDVB-12 NTs) through a fast oxidative initiation method. PDVB-12/PPy NTs exhibits good loading capacity (72.9 wt %) for industrial paraffin wax (IPW) due to the large specific surface area, and the resulting FSPCM composite (IPW@PDVB-12/PPy) exhibits a large latent heat of fusion (145.7 J/g), high thermal stability, and excellent shape stability. In addition, PPy imparts the IPW@PDVB-12/PPy composite with high electrical conductivity (55.6 S m-1) and high photoabsorption ability (whole visible light band). The energy stored in the IPW@PDVB-12/PPy composite could be triggered and released under relatively low voltages (2.5 V) with electrothermal energy conversion efficiency (89.6%) or solar radiation (100 mW cm-2) with photothermal energy conversion efficiency (85.2%). This study provides a low-cost and fast method for large-scale fabrication of supporting materials, which can be a good candidate in energy storage applications.

2.
J Contam Hydrol ; 241: 103815, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33964551

RESUMO

In the contaminant remediation of groundwater, the release history of contaminant sources and hydraulic conductivity field are two key parameters that need to know, but their actual values are difficult to obtain and can only be inversely identified by limited measured data. However, the process of solving the inverse problem needs to repeatedly call the forward model of contaminant transport, which is very time-consuming, especially for the high-dimensional inverse problems. In this study, based on the training data generated from a prior range of parameters (the release strength of contaminant sources and hydraulic conductivity at pilot points), the self-organizing maps (SOM) algorithm was employed to construct the surrogate model for the numerical model of contaminant transport in a simplified hypothetical aquifer, then the surrogate model was used to retrieve jointly the contaminant strength of sources and the hydraulic conductivity at pilot points, and the Kriging method of geostatistics was further used to process the estimated K-values at pilot points to obtain the hydraulic conductivity field. Also, to investigate the ability of the SOM-based surrogate model for retrieving both contaminant source strengths and hydraulic conductivity, we gradually expanded the prior range and increased the number of inversion terms in each prior range. Moreover, the robustness of the SOM-based surrogate model for inversion was illustrated by proposing the scarcity of data and different degrees of measurement error in the limited actual observation data. When the actual observation data is reduced by 2/3, the Root Mean Square Error (RMSE) of retrieving source strengths and hydraulic conductivity at pilot points are 1.07 and 0.09, respectively. The results indicated the SOM-based surrogate model shows remarkable inversion precision and robustness, and an accurate estimation of the actual hydraulic conductivity field could be obtained by the Kriging method based on that.

3.
Bioconjug Chem ; 32(6): 1094-1104, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34013721

RESUMO

Antibody-drug conjugates (ADCs) are complex pharmaceutical molecules that combine monoclonal antibodies with biologically active drugs through chemical linkers. ADCs are designed to specifically kill disease cells by utilizing the target specificity of antibodies and the cytotoxicity of chemical drugs. However, the traditional ADCs were only applied to a few disease targets because of some limitations such as the huge molecular weight, the uncontrollable coupling reactions, and a single mechanism of action. Here we report a simple, one-pot, successive reaction method to produce dual payload conjugates with the site-specifically engineered cysteine and p-acetyl-phenylalanine using Herceptin (trastuzumab), an anti-HER2 antibody drug widely used for breast cancer treatment, as a tool molecule. This strategy enables antibodies to conjugate with two mechanistically distinct cytotoxic drugs through different functional groups sequentially, therefore, rendering the newly designed ADCs with functional diversity and the potential to overcome drug resistance and enhance the therapeutic efficacy.

4.
Dalton Trans ; 50(23): 8243-8257, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34036954

RESUMO

Eleven copper chloride coordination compounds (1-11) with 4'-(4'-substituted-phenyl)-2,2':6',2''-terpyridine ligands bearing hydrogen (L1), cyano (L2), p-hydroxyl (L3), m-hydroxyl (L4), o-hydroxyl (L5), methoxyl (L6), iodo (L7), bromo (L8), chloro (L9), fluoro (L10) or methylsulfonyl (L11) were prepared and characterized by IR spectroscopy, elemental analysis and single crystal X-ray diffraction. Antiproliferative activities against tumor cells were investigated and DNA interactions were studied by circular dichroism spectroscopy and molecular modeling methods. In vitro data demonstrate that all the compounds exhibit higher antiproliferative activities as compared to cisplatin against five human carcinoma cell lines: A549, Bel-7402, Eca-109, HeLa and MCF-7. Compound 6 with methoxyl shows the best anti-proliferation activity. Spectrophotometric results reveal the strong affinity of the compounds for binding with DNA as intercalators and induce DNA conformational transitions. The results of molecular docking studies show that the compounds interact with DNA through π-π stacking, van der Waals forces, hydrophobic interactions and hydrogen bonds. The binding energies between compound 11 and three macromolecules, including DNA duplex, oligonucleotide and DNA-Topo I complex, are the lowest. The binding stability of compounds containing hydroxyl, methoxy and methylsulfonyl groups with biological macromolecules mainly relies on the hydrogen bonds. The ability of a compound to form hydrogen bonds can promote its binding to biological targets, thereby exhibiting high antiproliferative activity.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33923225

RESUMO

Exploring the relationship between environmental air quality (EAQ) and climatic conditions on a large scale can help better understand the main distribution characteristics and the mechanisms of EAQ in China, which is significant for the implementation of policies of joint prevention and control of regional air pollution. In this study, we used the concentrations of six conventional air pollutants, i.e., carbon monoxide (CO), sulfur dioxide (SO2), nitrogen dioxide (NO2), fine particulate matter (PM2.5), coarse particulate matter (PM10), and ozone (O3), derived from about 1300 monitoring sites in eastern China (EC) from January 2015 to December 2018. Exploiting the grading concentration limit (GB3095-2012) of various pollutants in China, we also calculated the monthly average air quality index (AQI) in EC. The results show that, generally, the EAQ has improved in all seasons in EC from 2015 to 2018. In particular, the concentrations of conventional air pollutants, such as CO, SO2, and NO2, have been decreasing year by year. However, the concentrations of particulate matter, such as PM2.5 and PM10, have changed little, and the O3 concentration increased from 2015 to 2018. Empirical mode decomposition (EOF) was used to analyze the major patterns of AQI in EC. The first mode (EOF1) was characterized by a uniform structure in AQI over EC. These phenomena are due to the precipitation variability associated with the East Asian summer monsoon (EASM), referred to as the "summer-winter" pattern. The second EOF mode (EOF2) showed that the AQI over EC is a north-south dipole pattern, which is bound by the Qinling Mountains and Huaihe River (about 35° N). The EOF2 is mainly caused by seasonal variations of the mixed concentration of PM2.5 and O3. Associated with EOF2, the Mongolia-Siberian High influences the AQI variation over northern EC by dominating the low-level winds (10 m and 850 hPa) in autumn and winter, and precipitation affects the AQI variation over southern EC in spring and summer.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Monitoramento Ambiental , Mongólia , Material Particulado/análise , Estações do Ano
6.
Planta ; 253(5): 112, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33914134

RESUMO

MAIN CONCLUSION: We discovered a potential defense pathway of cucumber to downy mildew. The signaling that activates the pathways of ROS and lignin accumulation may play an important role in the defense response. Many resistance genes were identified by transcriptome analysis. Downy mildew (DM), caused by Pseudoperonospora cubensis, is one of the most destructive diseases and causes severe yield losses of cucumber. However, the genes and pathways involved in regulating DM resistance were still poorly understood. In our study, we observed that the highly sensitive inbred line 53 (IL53) exhibited more severe disease symptoms than the highly resistant inbred line 51 (IL51) under P. cubensis infection. Furthermore, lignin, limiting the germination and extension of P. cubensis, and H2O2, as a signaling molecule during the resistant process, were both shown to increase, indicating that the signaling that activates these pathways might be responsible for the resistance divergence between IL51 and IL53. Transcriptome analysis, using the resistant and susceptible pools in F2 populations with IL51 and IL53 as parents, showed that a series of differentially expressed genes was involved in multiple functions of defense response: pathogen-associated molecular pattern recognition, signal transduction, reactive oxygen species and lignin accumulation, and transcription regulators. Combining physiological data with transcriptomes, we predicted a potential molecular mechanism of cucumber resistance to DM. Our research provided a foundation for further studies on the mechanism of cucumber resistance to DM.


Assuntos
Cucumis sativus , Peronospora , Cucumis sativus/genética , Resistência à Doença/genética , Perfilação da Expressão Gênica , Peróxido de Hidrogênio , Doenças das Plantas/genética , Transcriptoma/genética
7.
Int Immunopharmacol ; 94: 107507, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33657523

RESUMO

Hemorrhagic transformation (HT) is a frequent complication of ischemic stroke after thrombolytic therapy and seriously affects the prognosis of stroke. Due to the limited therapeutic window and hemorrhagic complications, tissue plasminogen activator (t-PA) is underutilized in acute ischemic stroke. Currently, there are no clinically effective drugs to decrease the incidence of t-PA-induced HT. Hypoxia-inducible factor 1 (HIF-1) is an important transcription factor that maintains oxygen homeostasis and mediates neuroinflammation under hypoxia. However, the effect of HIF-1 on t-PA-induced HT is not clear. The aim of this study was to investigate the role of HIF-1 in t-PA-induced HT by applying YC-1, an inhibitor of HIF-1. In the present study, we found that HIF-1 expression was significantly increased in ischemic brain tissue after delayed t-PA treatment and was mainly localized in neurons and endothelial cells. Inhibition of HIF-1 by YC-1 improved infarct volume and neurological deficits. YC-1 inhibited matrix metalloproteinase protein expression, increased tight junction protein expression, and ameliorated BBB disruption and the occurrence of HT. Furthermore, YC-1 suppressed the release of inflammatory factors, neutrophil infiltration and the activation of the HMGB1/TLR4/NF-κB signaling pathway. These results demonstrated that inhibition of HIF-1 could protect BBB integrity by suppressing HMGB1/TLR4/NF-κB-mediated neutrophil infiltration, thereby reducing the risk of t-PA-induced HT. Thus, HIF-1 may be a potential therapeutic target for t-PA-induced HT.


Assuntos
Isquemia Encefálica/imunologia , Hemorragia Cerebral/imunologia , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Acidente Vascular Cerebral/imunologia , Tromboembolia/imunologia , Ativador de Plasminogênio Tecidual , Animais , Células Endoteliais/efeitos dos fármacos , Proteína HMGB1/imunologia , Indazóis/farmacologia , Masculino , NF-kappa B/imunologia , Infiltração de Neutrófilos/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Ratos Sprague-Dawley , Receptor 4 Toll-Like/imunologia
8.
J Card Surg ; 36(6): 2029-2034, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33738816

RESUMO

OBJECTIVE: This study aimed to evaluate the long-term outcomes of patients with patent ductus arteriosus (PDA) associated with unilateral absence of a pulmonary artery (UAPA). METHODS: Patients diagnosed with PDA associated with UAPA between January 2005 and June 2019 were retrospectively enrolled in this study. Demographic and clinical characteristics, treatments, and follow-up information were evaluated. RESULTS: A total of 11 patients were diagnosed with PDA associated with UAPA. Percutaneous closure was successfully conducted in nine patients. The mean diameters of the PDA measured by aortogram and occluders were 5.3 ± 1.8 mm and 11.5 ± 3.9 mm, respectively. The median pulmonary systemic flow ratio (Qp:Qs) in five patients was 1.41, and the median total lung resistance was 12 Wood Units. The mean systolic pulmonary artery (PA) pressure was 68.3 ± 19.1 mmHg. In five patients with pre- and postprocedure catheter data, the systolic pulmonary arterial pressure decreased significantly after closure (from 77.0 ± 20.2 to 58.8 ± 17.5 mmHg; p = .024), as did the mean pulmonary arterial pressure (from 58.2 ± 14.6 to 39.0 ± 14.1 mmHg; p = .18). The PA pressure and heart size gradually decreased to normal levels in eight patients, and their quality of life was significantly improved. The ratio of lung to systemic circulation pressure was less than 0.75. CONCLUSIONS: In appropriate patients with PDA associated with UAPA, transcatheter closure of PDA has the potential to improve PA hypertension. A ratio of lung to systemic circulation pressure less than 0.75 may be an important reference index for predicting whether PA pressure can be reduced to a normal level after occlusion.


Assuntos
Permeabilidade do Canal Arterial , Cateterismo Cardíaco , Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/cirurgia , Humanos , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia , Qualidade de Vida , Estudos Retrospectivos , Sístole , Resultado do Tratamento
9.
Autophagy ; : 1-15, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33629929

RESUMO

Glioma is the most common primary malignant brain tumor with poor survival and limited therapeutic options. The non-psychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against glioma; however, the molecular target and mechanism of action of CBD in glioma are poorly understood. Here we investigated the molecular mechanisms underlying the antitumor effect of CBD in preclinical models of human glioma. Our results showed that CBD induced autophagic rather than apoptotic cell death in glioma cells. We also showed that CBD induced mitochondrial dysfunction and lethal mitophagy arrest, leading to autophagic cell death. Mechanistically, calcium flux induced by CBD through TRPV4 (transient receptor potential cation channel subfamily V member 4) activation played a key role in mitophagy initiation. We further confirmed TRPV4 levels correlated with both tumor grade and poor survival in glioma patients. Transcriptome analysis and other results demonstrated that ER stress and the ATF4-DDIT3-TRIB3-AKT-MTOR axis downstream of TRPV4 were involved in CBD-induced mitophagy in glioma cells. Lastly, CBD and temozolomide combination therapy in patient-derived neurosphere cultures and mouse orthotopic models showed significant synergistic effect in both controlling tumor size and improving survival. Altogether, these findings showed for the first time that the antitumor effect of CBD in glioma is caused by lethal mitophagy and identified TRPV4 as a molecular target and potential biomarker of CBD in glioma. Given the low toxicity and high tolerability of CBD, we therefore propose CBD should be tested clinically for glioma, both alone and in combination with temozolomide.Abbreviations: 4-PBA: 4-phenylbutyrate; AKT: AKT serine/threonine kinase; ATF4: activating transcription factor 4; Baf-A1: bafilomycin A1; CANX: calnexin; CASP3: caspase 3; CAT: catalase; CBD: cannabidiol; CQ: chloroquine; DDIT3: DNA damage inducible transcript 3; ER: endoplasmic reticulum; GBM: glioblastoma multiforme; GFP: green fluorescent protein; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; PARP1: poly(ADP-ribose) polymerase; PINK1: PTEN induced kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; SLC8A1: solute carrier family 8 member A1; SQSTM1: sequestosome 1; TCGA: The cancer genome atlas; TEM: transmission electron microscopy; TMZ: temozolomide; TRIB3: tribbles pseudokinase 3; TRPC: transient receptor potential cation channel subfamily C; TRPV4: transient receptor potential cation channel subfamily V member 4.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33573358

RESUMO

Given that there are no practical quantitative indicators of traffic conditions for facility location selection in the process of urbanization, this article proposes a comprehensive accessibility index of location and its measurement method. Urban land is rasterized using GIS to obtain the grids, and the road network data are used to calculate the external accessibility and internal accessibility of the grids. The external accessibility and the internal accessibility of a grid are combined to obtain the comprehensive accessibility of the location. The comprehensive accessibilities of grids are measured for Zhicheng, an urban area in China. The results show that the pattern of gradual spatial changes in the comprehensive accessibility of the grids in Zhicheng is highly consistent with the urban land's spatial development trend, which verifies the feasibility and accuracy of the comprehensive accessibility measurement method. On one hand, the comprehensive accessibility of the grid is more portable than the accessibility of a single point and can be calculated in batches. On the other hand, it is more specific than the regional accessibility and better guides the location selection of urban facilities.


Assuntos
Reforma Urbana , Urbanização , China
11.
Clin Res Hepatol Gastroenterol ; 45(2): 101312, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33592427

RESUMO

BACKGROUND: The morbidity of nonalcoholic fatty liver disease (NAFLD) has increased consistently in recent years. Exenatide could reverse liver fibrosis and lower the occurrence of fatty liver. The aim of the study was to identify and characterize mRNA and miRNA expression to elucidate the mechanism of exenatide in the gerbil model. METHODS: Gerbils were fed a high-fat diet for 8 weeks to induce a fibrosis model; then, the gerbil models were treated with exenatide for 4 weeks. The total RNA extracted from the liver tissue samples was used to prepare the library and sequence on a HiSeq 2000. Bioinformatic methods were employed to analyze the sequence data to identify the mRNAs and miRNAs and to acquire the miRNA-mRNA regulatory network. RESULTS: By RNA-seq, 2344 differentially expressed genes (DEGs) and 72 miRNAs were found in the model group. Compared with the model group, 591 DEGs and 19 miRNAs were found in the quercetin group, whereas 876 DEGs and 18 miRNAs were found in the treatment group. The miRNA-mRNA regulatory network was constructed in a gerbil model. Immunohistochemistry and RNA sequencing confirmed that the therapeutic effect of exenatide may be derived from extrahepatic signal transduction. The key differential genes are CYP3A, CYP4A11, ACAA1, ACSM, PHX1, MAO, FMO, UGT, ACOX2, ABAT, PIK3C and PLCG1. The key miRNAs are miR-15a, miR-27b, miR-532-3P, miR-627, miR-3596, miR-142-3P, Let-7e-5p, miR-214-5, miR-101-3p, miR-378d. New miRNAs, such as novel_127, novel_143, novel_15, novel_204 are associated with liver fibrosis, while novel_127, novel_15, and novel_54 are associated with reverse treated with exenatide. CONCLUSIONS: Our research represents the first description of mRNA/miRNA profiles in a gerbil model of fatty liver fibrosis treated with exenatide, which may provide insights into the pathogenesis or treatment of the metabolic syndrome.

12.
Medicine (Baltimore) ; 100(7): e24788, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33607833

RESUMO

RATIONALE: In recent decades, the incidence of advanced syphilis has declined due to early recognition and the application of effective antibiotics. Advanced syphilis often manifests in the cardiovascular system as simple aortitis, aortic valve insufficiency, coronary artery stenosis or obstruction, Aortic aneurysm and mucinous myocarditis. In most case reports on the subject, acute myocardial infarction caused by syphilis was reported to be due to aortic valve insufficiency and coronary stenosis as a result of the involvement of the aorta. PATIENT CONCERNS: The patient was a 48-year-old woman. She was admitted to our hospital because of intermittent upper abdominal pain with chest tightness for 3 hours. The patient reported a past syphilis infection, when she was hospitalized for hysteromyoma surgery four years ago, and had no related treatment. DIAGNOSIS: According to the characteristics of coronary angiography and results of lab tests and echocardiography, she was finally diagnosed with myocardial infarction associated with syphilis. INTERVENTIONS: At the first diagnosis of syphilis, the patient did not received antibiotics treatment. After the diagnosis of myocardial infarction, she received the percutaneous coronary intervention (PCI) operation assisted by extracorporeal membrane oxygenation (ECMO) technology, successfully got drug -eluted stents in right coronary artery ostium and left main ostium. Then the patient received penicillin to treat the syphilis infection. OUTCOMES: After coronary revascularization, the cardiac function of the patients was gradually improved, and the left ventricular ejection fraction was gradually improved after combined with optimized drug therapy. LESSONS: The cardiovascular system is often involved in the stages of advanced syphilis with severe complications like myocardial infarction. Standard treatment should be given as soon as syphilis is diagnosis. For stenosis of coronary ostium, the PCI assisted by ECMO technology did not only ensure the effectiveness of the treatment, but also reduce the surgical risk of the patient. This case indicated the effectiveness of ECMO-assisted PCI, and thus may provide a reference for future patient treatment.


Assuntos
Infarto do Miocárdio/etiologia , Sífilis Cardiovascular/complicações , Angiografia Coronária , Ecocardiografia , Oxigenação por Membrana Extracorpórea , Feminino , Humanos , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Penicilinas/uso terapêutico , Intervenção Coronária Percutânea , Sífilis Cardiovascular/tratamento farmacológico , Resultado do Tratamento
13.
Artigo em Inglês | MEDLINE | ID: mdl-33616703

RESUMO

Large quantities of microplastics (MPs) are discharged into the hydrosphere via the municipal wastewater treatment plant (WWTP) as an important route. Herein, we sampled the influent, effluent and sludge of WWTP in order to investigate the abundance, size, type, and shape of MPs. The detected MPs were primarily in the shape of fiber with the abundance up to 44 particles per liter. Polyethylene terephthalate, polypropylene, and polyethylene were found to be the three largest types of MPs. MPs in the influent was effectively eliminated with a removal efficiency of ~ 96%. However, a large quantity of MPs was still discharged in the effluent and the excess sludge, approximately 2.87 × 108 particles per day, indicating that some specific control facilities should be installed at WWTP to minimize the environmental impacts of MPs.

14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 35(1): 104-110, 2021 Jan 15.
Artigo em Chinês | MEDLINE | ID: mdl-33448207

RESUMO

Objective: After using hyaluronic acid (HA) to modify curcumin (CUR), the effects of calcium phosphate cement (CPC) combined with HA/CUR on the proliferation and osteogenesis of osteoblasts were investigated. Methods: First, HA and CUR were esterified and covalently combined to prepare HA/CUR, and the characteristics were observed and the infrared spectrum was tested. Then, HA, CUR, and HA/CUR were mixed with CPC according to 5% ( W/ W) to prepare HA-CPC, CUR-CPC, and HA/CUR-CPC, respectively. Setting time detection, scanning electron microscope observation, injectable performance test, and compression strength test were conducted; and the CPC was used as a control. Osteoblasts were isolated and cultured from the skull of newborn Sprague Dawley rats, and the 2nd generation cells were cultured with the 4 types of bone cement, respectively. The effects of HA/CUR-CPC on the proliferation and osteogenesis of osteoblasts were estimated by the scanning electron microscopy observation, live/dead cell fluorescence staining, cell counting, osteopontin (OPN) immunofluorescence staining, alkaline phosphatase (ALP) staining,and alizarin red staining. Results: Infrared spectroscopy test showed that HA and CUR successfully covalently combined. The HA/CUR-CPC group had no significant difference in initial setting time, final setting time, injectable rate, and compressive strength when compared with the other 3 groups ( P>0.05); scanning electron microscope observation showed that HA/CUR was scattered on CPC surface. After co-culture of bone cement and osteoblasts, scanning electron microscopy observation showed that the osteoblasts, which had normal morphology and the growth characteristics of osteoblasts, clustered and adhered to HA/CUR-CPC. There was no significant difference in cell survival rate between HA/CUR-CPC group and other groups ( P>0.05), and the number of cells significantly increased ( P<0.05); the degrees of OPN immunofluorescence staining, ALP staining, and alizarin red staining were stronger than other groups. Conclusion: HA/CUR-CPC has good biocompatibility and mechanical properties, which can promote the proliferation and osteogenesis of osteoblasts.


Assuntos
Curcumina , Osteogênese , Animais , Cimentos Ósseos , Fosfatos de Cálcio/farmacologia , Proliferação de Células , Curcumina/farmacologia , Ácido Hialurônico/farmacologia , Osteoblastos , Ratos , Ratos Sprague-Dawley
15.
J Appl Toxicol ; 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33469990

RESUMO

Mitochondria are important organelles in human cells, providing more than 95% of the energy. However, some drugs and environmental chemicals could induce mitochondrial dysfunction, which might cause complex diseases and even worsen the condition of patients with mitochondrial damage. Some drugs have been withdrawn from the market due to their severe mitochondrial toxicity, such as troglitazone. Therefore, there is an urgent need to develop models that could accurately predict the mitochondrial toxicity of chemicals. In this paper, suitable data were obtained from literature and databases first. Then nine types of fingerprints were used to characterize these compounds. Finally, different algorithms were used to build models. Meanwhile, the applicability domain of the prediction models was defined. We have also explored the structural alerts of mitochondrial toxicity, which would be helpful for medicinal chemists to better predict mitochondrial toxicity and further optimize lead compounds.

16.
Nat Commun ; 12(1): 303, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436610

RESUMO

The construction of enzyme-inspired artificial catalysts with enzyme-like active sites and microenvironment remains a great challenge. Herein, we report a single-atomic-site Co catalyst supported by carbon doped boron nitride (BCN) with locally polarized B-N bonds (Co SAs/BCN) to simulate the reductive dehalogenases. Density functional theory analysis suggests that the BCN supports, featured with ionic characteristics, provide additional electric field effect compared with graphitic carbon or N-doped carbon (CN), which could facilitate the adsorption of polarized organochlorides. Consistent with the theoretical results, the Co SAs/BCN catalyst delivers a high activity with nearly complete dechlorination (~98%) at a potential of -0.9 V versus Ag/AgCl for chloramphenicol (CAP), showing that the rate constant (k) contributed by unit mass of metal (k/ratio) is 4 and 19 times more active than those of the Co SAs/CN and state-of-the-art Pd/C catalyst, respectively. We show that Co single atoms coupled with BCN host exhibit high stability and selectivity in CAP dechlorination and suppress the competing hydrogen evolution reaction, endowing the Co SAs/BCN as a candidate for sustainable conversion of organic chloride.

17.
Toxicol In Vitro ; 72: 105089, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33444712

RESUMO

In recent years, the decline of honey bees and the collapse of bee colonies have caught the attention of ecologists, and the use of pesticides is one of the main reasons for the decline. Therefore, ecological risk assessment of pesticides is essential and necessary. In silico tools, such as QSAR models can play an important role in predicting physicochemical and biological properties of chemicals. In this study, a total of 54 classification models were developed by combination of 6 machine learning methods along with 9 kinds of molecular fingerprints based on the experimental honey bees acute contact toxicity data (LD50) of 676 structurally diverse pesticides. The best model proposed was SVM algorithm combined with CDK extended fingerprint. The analysis of the applicability domain of the model successfully excluded some extreme molecules. Additionally, 9 structural alerts about honey bees acute contact toxicity were identified by information gain and substructure frequency analysis.

18.
Prep Biochem Biotechnol ; : 1-11, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439089

RESUMO

Crude glycerol, a by-product of biodiesel production, was employed as the carbon source to produce lipase using Pichia pastoris. Under identical fermentation conditions, cell growth and lipase activity were improved using crude glycerol instead of pure glycerol. The impacts of crude glycerol impurities (methyl ester, grease, glycerol, methanol, and metal ions Na+, Ca2+, and Fe3+) on lipase production were investigated. Impurities accelerated P. pastoris entering the stationary phase. Na+, Ca2+, and grease in waste crude glycerol were the main factors influencing higher lipase activity. Through response surface optimization of Ca2+, Na+, and grease concentrations, lipase activity reached 1437 U/mL (15,977 U/mg), which was 2.5 times that of the control. This study highlights the economical and highly efficient valorization of crude glycerol, demonstrating its possible utilization as a carbon source to produce lipase by P. pastoris without pretreatment.

19.
Sheng Wu Gong Cheng Xue Bao ; 37(1): 88-99, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33501792

RESUMO

The formation of most proteins consists of two steps: the synthesis of precursor proteins and the synthesis of functional proteins. In these processes, propeptides play important roles in assisting protein folding or inhibiting its activity. As an important polypeptide chain coded by a gene sequence in lipase gene, propeptide usually functions as an intramolecular chaperone, assisting enzyme molecule folding. Meanwhile, some specific sites on propeptide such as glycosylated sites, have important effect on the activity, stability in extreme environment, methanol resistance and the substrate specificity of the lipase. Studying the mechanism of propeptide-mediated protein folding, as well as the influence of propeptide on lipases, will allow to regulate lipase by alternating the propeptide folding behavior and in turn pave new ways for protein engineering research.


Assuntos
Lipase , Dobramento de Proteína , Lipase/genética , Lipase/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Precursores de Proteínas , Especificidade por Substrato
20.
Cell Biol Int ; 45(4): 820-830, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33325118

RESUMO

Rupture of atherosclerotic plaques constitutes the major cause of thrombosis and acute ischemic coronary syndrome. Bone marrow-derived mesenchymal stem cells microvesicles (BMSCs-MVs) are reported to promote angiogenesis. This study investigated the role of BMSCs-MVs in stabilizing atherosclerotic plaques. BMSCs-MVs in mice were isolated and identified. The mouse model of atherosclerosis was established, and mice were injected with BMSCs-MVs via the tail vein. The macrophage model with high glucose and oxidative damage was established and then incubated with BMSCs-MVs. Nod-like receptor protein 3 (NLRP3) expression, pyroptosis-related proteins, and inflammatory factors were detected. Actinomycin D was used to inhibit the secretion of BMSCs-MVs to verify the source of microRNA-223 (miR-223). The binding relationship between miR-223 and NLRP3 was predicted and verified. BMSCs-MVs with knockdown of miR-223 were cocultured with bone marrow-derived macrophages with knockdown of NLRP3, and then levels of miR-223, NLRP3, pyroptosis-related proteins, and inflammatory factors were detected. BMSCs-MVs could reduce the vulnerability index of atherosclerotic plaques and intima-media thickness in mice, and inhibit pyroptosis and inflammation. BMSCs-MVs inhibited pyroptosis and inflammatory factors in macrophages. BMSCs-MVs carried miR-223 to inhibit NLRP3 expression and reduce macrophage pyroptosis, thereby stabilizing the atherosclerotic plaques.

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