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1.
Dis Model Mech ; 16(10)2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37728477

RESUMO

Tissue injury-induced neutrophil recruitment is a prerequisite for the initiation and amplification of inflammatory responses. Although multiple proteases and enzymes involved in post-translational modification (PTM) of proteins regulate leukocyte recruitment, an unbiased functional screen of enzymes regulating inflammatory leukocyte recruitment has yet to be undertaken. Here, using a zebrafish tail fin amputation (TFA) model to screen a chemical library consisting of 295 compounds that target proteases and PTM enzymes, we identified multiple histone deacetylase (HDAC) inhibitors that modulate inflammatory neutrophil recruitment. AR-42, a pan-HDAC inhibitor, was shown to inhibit neutrophil recruitment in three different zebrafish sterile tissue injury models: a TFA model, a copper-induced neuromast damage and mechanical otic vesicle injury (MOVI) model, and a sterile murine peritonitis model. RNA sequencing analysis of AR-42-treated fish embryos revealed downregulation of neutrophil-associated cytokines/chemokines, and exogenous supplementation with recombinant human IL-1ß and CXCL8 partially restored the defective neutrophil recruitment in AR-42-treated MOVI model fish embryos. We thus demonstrate that AR-42 non-cell-autonomously modulates neutrophil recruitment by suppressing transcriptional expression of cytokines/chemokines, thereby identifying AR-42 as a promising anti-inflammatory drug for treating sterile tissue injury-associated diseases.


Assuntos
Inibidores de Histona Desacetilases , Peixe-Zebra , Humanos , Animais , Camundongos , Inibidores de Histona Desacetilases/farmacologia , Infiltração de Neutrófilos , Neutrófilos , Quimiocinas , Peptídeo Hidrolases
2.
Animals (Basel) ; 13(14)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37508030

RESUMO

African swine fever is a highly contagious virus that causes pig disease. Its onset process is short, but the mortality rate is as high as 100%. There are still no effective drugs that have been developed to treat African swine fever, and prevention and control measures are currently the best means to avoid infection in pig herds. In this paper, two fractional order mathematical models with media coverage are constructed to describe the transmission of African swine fever. The first model is a basic model with media coverage, and no control measures are considered. For this model, the reproduction number is obtained by using the next generation matrix method. Then, the sufficient conditions for the existence and stability of two equilibriums are obtained. Based on the first model, the second model is established incorporating two control measures. By using Pontryagin's maximal principle, the optimal control solution is derived. After that, some numerical simulations are performed for the two models to verify the theoretical results. Both the qualitative analysis and numerical results indicate that timely media coverage combined with disinfection control measures is crucial to preventing the spread of disease.

3.
J Immunol ; 211(3): 462-473, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37326485

RESUMO

Cell spreading is an initial and critical step in neutrophil adhesion and migration, leading to neutrophil recruitment to inflammatory tissues. Sideroflexin (Sfxn) family proteins are metabolite transporters located in the mitochondrial membrane. Recombinant SFXN5 protein is a citrate transporter in vitro; however, whether Sfxn5 regulates any cellular behavior or function remains unknown. In this study, we found that small interfering RNA transfection or morpholino injection achieving Sfxn5 deficiency in neutrophils significantly decreased neutrophil recruitment in mice and zebrafish, respectively. Sfxn5 deficiency impaired neutrophil spreading and spreading-associated cellular phenotypes, such as cell adhesion, chemotaxis, and ROS production. Actin polymerization is critical for neutrophil spreading, and we found that actin polymerization in spreading neutrophils was partially inhibited by Sfxn5 deficiency. Mechanistically, we observed that the levels of cytosolic citrate and its downstream metabolic products, acetyl-CoA and cholesterol, were decreased in Sfxn5-deficient neutrophils. The levels of phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a mediator for the regulation of actin polymerization by cholesterol, were reduced in the plasma membrane of Sfxn5-deficient neutrophils. Exogenous supplementation with citrate or cholesterol partially reversed the reduction in PI(4,5)P2 levels, defective neutrophil actin polymerization, and cell spreading. Altogether, we demonstrated that Sfxn5 maintains cytosolic citrate levels and ensures the synthesis of sufficient cholesterol to promote actin polymerization in a PI(4,5)P2-dependent manner during neutrophil spreading, which is essential for the eventual inflammatory recruitment of neutrophils. Our study revealed the importance of Sfxn5 in neutrophil spreading and migration, thus identifying, to our knowledge, for the first time, the physiological cellular functions of the Sfxn5 gene.


Assuntos
Actinas , Neutrófilos , Animais , Camundongos , Actinas/metabolismo , Neutrófilos/metabolismo , Ácido Cítrico/metabolismo , Peixe-Zebra/metabolismo , Polimerização , Colesterol/metabolismo
4.
Int J Biol Macromol ; 244: 125386, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37327924

RESUMO

We designed targeted drug delivery systems containing folate (FOL), the functionalized carbon nanotube (f-CNT) and doxorubicin (DOX), and studied the targeting properties of folate, f-CNT-FOL and DOX/f-CNT-FOL to folate receptor α (FRα). Folate was actively targeted to FRα in molecular dynamics simulations, and the dynamic process, effect of folate receptor evolution, and characteristics were analyzed. On this basis, the f-CNT-FOL and DOX/f-CNT-FOL nano-drug-carrier systems were designed, and the drug delivery process targeted to FRα was studied by 4 times MD simulations. The system evolution and detailed interactions of f-CNT-FOL and DOX/f-CNT-FOL with FRα residues were examined. We found that though the connection of CNT with the FOL could decrease the insertion depth of the pterin of FOL into the pocket of FRα, the loading of drug molecules could reduce this effect. Representative snapshots from the MD simulations were analyzed, showing that the location of DOX on the surface of CNT was constantly changed during the MD simulation, but the surface of the four rings of DOX were almost always parallel to the surface of CNT. The RMSD and RMSF were used to further analyze. The results may provide new insights for the design of novel targeted nano-drug-delivery systems.


Assuntos
Simulação de Dinâmica Molecular , Nanotubos de Carbono , Nanotubos de Carbono/química , Receptor 1 de Folato/metabolismo , Ácido Fólico/química , Sistemas de Liberação de Medicamentos/métodos , Doxorrubicina/química , Portadores de Fármacos/química
5.
Phys Chem Chem Phys ; 25(19): 13265-13274, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-36924456

RESUMO

Inspired by the requirements of miniaturization and multifunction of molecular devices, we investigate the quantum transport properties of three unique molecular devices with silicon carbide chains bridging gold electrodes by an ab initio approach. The pronounced quantum effects, including the oscillation of charge, conductance, and current, together with the negative differential resistance (NDR), have been observed simultaneously over a wide region in the double-chain device. It changes the regular situation that these two effects usually emerge in single-chain systems at the same time. Inspections of the visible differences in the transport behaviors relevant to length and bias between the three devices further evidence that the interchain interaction and molecule-electrode coupling are decisive factors for achieving the quantum effects of oscillation and NDR. These two factors can improve electronic transport capability through enhancing transmission, strengthening the delocalization of frontier molecular orbitals, and reducing potential barriers. Our results not only lay a solid foundation for the application of silicon carbide chains in the miniaturized and multifunctional molecular devices with good performance, but also provide an efficient way to the continuing search for materials with multiple controllable quantum effects in nanoelectronics.

6.
J Biomol Struct Dyn ; 41(19): 9602-9613, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36373329

RESUMO

Since the main protease (Mpro) is crucial for the COVID-19 virus replication and transcription, searching for Mpro inhibitors is one possible treatment option. In our study, 258 small molecules were collected from lung-related herbal medicines, and their structures were optimized with the B3LYP-D3/6-31G* method. After the molecular docking with Mpro, we selected the top 20 compounds for the further geometry optimization with the larger basis sets. After the further molecular docking, the top eight compounds were screened out. Then we performed molecular dynamics simulations and binding free energy calculations to determine stability of the complexes. Our results show that mulberrofuran G, Xambioona, and kuwanon D can bind Mpro well. In quantum chemistry studies, such as ESP and CDFT analyses, the compounds properties are predicted. Additionally, the drug-likeness analyses and ADME studies on these three candidate compounds verified that all of them conform to Libinski's rule and may be drug-like compounds.


Assuntos
COVID-19 , Plantas Medicinais , Simulação de Acoplamento Molecular , SARS-CoV-2 , Simulação de Dinâmica Molecular , Inibidores de Proteases/farmacologia , Extratos Vegetais
7.
Front Cell Infect Microbiol ; 13: 1320933, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38268789

RESUMO

Background: In the context of increasing reports of co-infection with coronavirus disease 2019 (COVID-19), particularly with human herpes viruses (HHVs), it is important to consider the appropriate treatment options for HHVs that have been reactivated by COVID-19. Case presentation: This study presents two cases of severe COVID-19 with HHV co-infection. The first case involved a critically ill patient with COVID-19 co-infected with herpes simplex virus type 1, confirmed using metagenomic next-generation sequencing, and another patient with severe COVID-19 experiencing Epstein-Barr virus (EBV) reactivation, as evidenced by elevated EBV-DNA levels in the serum. Treatment included high-dose glucocorticoids and sivelestat sodium, with notable improvements observed after initiating ganciclovir anti-herpesvirus therapy. Conclusion: This study underscores the significance of recognizing HHV co-infections in severe COVID-19 cases and highlights the potential of combining anti-HHV treatment, increased glucocorticoid dosages, and anti-cytokine storm therapy to enhance prognosis.


Assuntos
COVID-19 , Coinfecção , Dermatite , Infecções por Vírus Epstein-Barr , Humanos , Coinfecção/tratamento farmacológico , COVID-19/complicações , Herpesvirus Humano 4 , Imunoterapia
8.
Int J Biochem Cell Biol ; 151: 106297, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36108948

RESUMO

Emphysematous phenotype is the most important phenotypic component of chronic obstructive pulmonary disease and is associated with substantial morbidity and mortality. The current pharmaceutical treatments and therapeutic procedures do not reduce pulmonary damage in patients with emphysematous phenotype. Therefore, it is important to identify effector molecules that can be used as interfering targets in such patients. Apoptosis of type II alveolar epithelial cells plays a key role in the phenotypic formation. This study aimed to further explore the molecular mechanisms involved in this process. The number of type II alveolar epithelial cells was significantly reduced due to increased apoptosis in patients with emphysematous phenotype compared to those with non-emphysematous phenotype. Pleckstrin homology like domain, family A, member 1 (PHLDA1) was mainly distributed in type II alveolar epithelial cells in both groups but was markedly reduced in patients with emphysematous phenotype. Overexpression of PHLDA1 prevented cigarette smoke extract-stimulated apoptosis of type II alveolar epithelial cells, whereas its knockdown worsened the apoptosis. PHLDA1 binding ability to tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein epsilon (YWHAE) was weakened after exposure to cigarette smoke extract, with decreased PHLDA1 level lowering the abundance of YWHAE and attenuating the binding ability of YWHAE to p-Bad. These results demonstrate that considerable apoptosis of type II alveolar epithelial cells occurs in patients with emphysematous phenotype, and PHLDA1 may act as an effective antiapoptotic factor via YWHAE. Moreover, PHLDA1 may serve as a potential interfering target, providing insights into therapeutic strategies for emphysematous phenotype.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Triptofano Hidroxilase/metabolismo , Triptofano , Células Epiteliais Alveolares , Apoptose/genética , Proteínas Sanguíneas , Humanos , Fenótipo , Fosfoproteínas , Triptofano/genética , Tirosina 3-Mono-Oxigenase/genética
9.
Diabetes Metab Syndr Obes ; 15: 2197-2205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35923251

RESUMO

Purpose: Trimethylamine N-oxide (TMAO) is a metabolite of phosphatidylcholine in red meat and other diets, which is associated with cardiovascular and other diseases. The aim of this study is to evaluate the associations of serum TMAO with mild cognitive impairment (MCI) in the Chinese type 2 diabetes mellitus (T2DM) population. Materials and Methods: A total of 253 hospitalized T2DM patients and 150 healthy controls were included in this cross-sectional study. Montreal Cognitive Assessment (MoCA) assessed the cognition function, and the 253 T2DM patients were divided into 74 subjects with MCI and 179 with non-MCI. Demographic data and biochemical test results were evaluated. Serum TMAO level was measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Results: A higher serum TMAO level was observed in T2DM patients compared with the healthy controls (P < 0.001). Among all T2DM patients, the MCI group (n = 74) showed higher serum TMAO levels than the non-MCI group. Spearman correlation test showed that TMAO levels were significantly positively correlated with age (r = 0.147, P = 0.019), body mass index (BMI) (r = 0.153, P = 0.015), diabetes duration (r = 0.160, P = 0.011), HbA1c (r = 0.138, P = 0.029), triglyceride (TG) (r = 0.138, P = 0.029), creatinine (r = 0.184, p = 0.003), hs-CRP (r = 0.243, P < 0.001), and were negatively correlated with HDL-C (r = -0.144, P = 0.022), BDNF (r = -0.165, p = 0.009), and MoCA (r = -0.386, P < 0.001) score (all P < 0.05). Multivariable Logistic regression identified high serum TMAO level as a significant independent factor of MCI in the T2DM patients (OR = 1.404, 95% CI = 1.255-1.571; P < 0.001). Conclusion: Our study showed that T2DM patients with MCI have elevated serum TMAO levels.

10.
J Mol Model ; 28(8): 205, 2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35780236

RESUMO

Eight novel fluorescent antifolates were designed and docked with folate receptors FRα and FRß. The structures of the complexes were further calculated by molecular dynamic (MD) simulations. The binding energies were calculated by molecular docking and molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) studies. The binding energy differences between FRα and FRß (|Ebα|-|Ebß|) values for compounds 3 and 8 were 1.3 and 1.1 kcal/mol calculated by molecular docking, and 13.9 and 10.4 kcal/mol by MM-PBSA simulation, respectively. The results indicated that compounds 3 and 8 may be the best candidates for targeted drug delivery to FRα. The binding structures, interaction residues, negatively charged pocket volume, and surface area were analyzed for all the complexes. We further calculated the root mean square displacement and secondary structural elements of the bound complexes using molecular dynamics simulations. The purpose of this study is to design novel antifolates targeted to FRα and FRß, and to further distinguish between cancer cells and inflammation.


Assuntos
Antagonistas do Ácido Fólico , Simulação de Dinâmica Molecular , Ácido Fólico , Antagonistas do Ácido Fólico/farmacologia , Simulação de Acoplamento Molecular
11.
RSC Adv ; 12(9): 5357-5368, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35425531

RESUMO

Recent outbreaks of coronavirus have brought serious challenges to public health around the world, and it is essential to find effective treatments. In this study, the 3C-like proteinase (3CLpro) of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) has been considered as an important drug target because of its role in viral replication. We initially optimized 251 compounds at the PM7 level of theory for docking with 3CLpro, and then we selected the top 12 compounds for further optimization with the B3LYP-D3/6-311G** method and obtained the top four compounds by further molecular docking. Quantum chemistry calculations were performed to predict molecular properties, such as the electrostatic potential and some CDFT descriptors. We also performed molecular dynamics simulations and free energy calculations to determine the relative stability of the selected four potential compounds. We have identified key residues controlling the 3CLpro/ligand binding from per-residue based decomposition of the binding free energy. Convincingly, the comprehensive results support the conclusion that the compounds have the potential to become a candidate for anti-coronavirus treatment.

12.
Front Mol Biosci ; 8: 650604, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277700

RESUMO

Chronic obstructive pulmonary disease (COPD) is a highly heterogeneous disease. Emphysematous phenotype is the most common and critical phenotype, which is characterized by progressive lung destruction and poor prognosis. However, the underlying mechanism of this structural damage has not been completely elucidated. A total of 12 patients with COPD emphysematous phenotype (COPD-E) and nine patients with COPD non-emphysematous phenotype (COPD-NE) were enrolled to determine differences in differential abundant protein (DAP) expression between both groups. Quantitative tandem mass tag-based proteomics was performed on lung tissue samples of all patients. A total of 29 and 15 lung tissue samples from patients in COPD-E and COPD-NE groups, respectively, were used as the validation cohort to verify the proteomic analysis results using western blotting. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were conducted for DAPs. A total of 4,343 proteins were identified, of which 25 were upregulated and 11 were downregulated in the COPD-E group. GO and KEGG analyses showed that wound repair and retinol metabolism-related pathways play an essential role in the molecular mechanism of COPD emphysematous phenotype. Three proteins, namely, KRT17, DHRS9, and FMO3, were selected for validation. While KRT17 and DHRS9 were highly expressed in the lung tissue samples of the COPD-E group, FMO3 expression was not significantly different between both groups. In conclusion, KRT17 and DHRS9 are highly expressed in the lung tissue of patients with COPD emphysematous phenotype. Therefore, these proteins might involve in wound healing and retinol metabolism in patients with emphysematous phenotype and can be used as phenotype-specific markers.

13.
Front Pharmacol ; 12: 669403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177583

RESUMO

Background: The mechanisms underlying differences in the susceptibility to chronic obstructive pulmonary disease (COPD) exacerbations between patients are not well understood. Recent studies have shown that the patients with frequent COPD exacerbations is related to specific protein expression in lung tissue. Anterior gradient 3 (AGR3) is expressed in airway epithelial cells in the lung and proteomic analysis revealed that its expression is decreased in patients with frequent COPD exacerbations. Moreover, the loss of epithelial integrity might facilitate trans-epithelial permeability of pathogens in such patients. This study was performed to determine that AGR3 protein play a role in COPD frequency exacerbators. Methods: Human lung tissues were collected from current-smoking patients (Control; n = 15) as well as patients with infrequent COPD exacerbations (IFCOPD; n = 18) and frequent COPD exacerbations (FCOPD; n = 8). While AGR3 protein expression was measured by immunohistochemistry and western blotting, AGR mRNA expression was determined by real time quantitative polymerase chain reaction (RT-qPCR). Furthermore, adherent junctions (AJs) and tight junctions (TJs) protein expression in human lung tissues were measured by immunohistochemistry. The effects of cigarette smoke extract (CSE) on AJ and TJ protein and mRNA expression in BEAS-2B cells were assessed by western blotting and RT-qPCR. In addition, the effect of AGR3 overexpression and knockdown on AJ and TJ protein expression was determined. Results: AGR3 was mainly expressed in the airway epithelium and AGR3-positive products were localized in the cytoplasm. Western blotting and RT-qPCR results showed that AGR3 protein (p = 0.009) and mRNA (p = 0.04) expression in the FCOPD group was significantly lower than that in the IFCOPD group. Moreover, E-cadherin, occludin, and zonula occludens-1 (ZO-1) expression was lower in the FCOPD group than in the IFCOPD group. The protein and mRNA expression of E-cadherin, occludin, and ZO-1 was decreased within 24 h post-CSE exposure. AGR3 overexpression rescued CSE-induced downregulation of E-cadherin, occludin, and ZO-1. Conclusion: Difference in AGR3 expression in the lung tissue might be correlated with increased susceptibility to COPD exacerbation. AGR3 can prevent CSE-induced downregulation of E-cadherin, occludin, and ZO-1 in airway epithelial cells. Loss of AGR3 might promote viral and bacterial infection and induce immune inflammation to increase COPD exacerbation.

14.
Cancer Manag Res ; 13: 3723-3737, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994812

RESUMO

INTRODUCTION: Glioma is the most common malignant brain tumor in adults. Radiation is a key therapy in glioma. However, the radioresistance of glioma was a big challenge. HLA complex P5 (HCP5) has been reported dysregulated in several types of malignant tumor, including glioma. The role of HCP5 in the radiosensitivity of glioma is so far unknown. The present study aimed to investigate the effect of HCP5 on radiosensitivity in gliomas. METHODS: The levels of HCP5 and microRNA (miR)-128 were detected using qRT-PCR. The cell growth curve was used to show the cell proliferation and evaluate the radiosensitivity of glioma cells following exposure to X-ray. Senescence-associated ß-galactosidase (SA-ß-Gal) staining was used to test the cellular senescence. Luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to determine the correlation between HCP5 and miR-128. RESULTS: HCP5 level of glioma cells was significantly higher than human astrocytes, whereas miR-128 level was lower in glioma cells. Besides, the HCP5 expression was increased in glioma tissues compared to normal brain tissues (NBTs). Knockdown of HCP5 inhibited cell proliferation and increased radiosensitivity in glioma cells. MiR-128 was predicted to be a target of HCP5. It was demonstrated that HCP5 directly bound to miR-128 and regulated its expression in glioma cells. Furthermore, the effects of HCP5 knockdown on radiosensitivity of glioma cells were attenuated by the inhibitor of miR-128. CONCLUSION: These findings suggested that interaction between lncRNA HCP5 and microRNA-128 could regulate the radiosensitivity of glioma cells by intervening in cellular senescence. This might be used as the potential radio-sensitization targets for glioma therapy.

15.
Rice (N Y) ; 14(1): 37, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33881644

RESUMO

Anthocyanins cause purple, brown or red colors in various tissues of rice plants, but the specific determinant factors and regulatory systems for anthocyanin biosynthesis in almost all tissues remain largely unknown. In the present study, we mapped and isolated two complementary genes, OsC1 encoding a R2R3-MYB transcriptional factor and OsDFR encoding a dihydroflavonol 4-reductase, which are responsible for the purple coloration of apiculi and stigmas in indica cultivar Xieqingzao by the map-based cloning strategy. We also identified two tissue-specific pigmentation genes, OsPa for apiculi and OsPs for stigmas, by phylogenetic analysis of all anthocyanin biosynthesis-associated bHLH transcriptional factors in maize and rice, CRISPR/Cas9 knockout and transcriptional expression analysis. The OsC1, OsPa and OsPs proteins are all localized in the nucleus while the OsDFR protein is localized in the nucleus and cytoplasm, and the OsC1 and OsDFR genes are preferentially strongly expressed in both purple-colored tissues while the OsPa and OsPs genes are preferentially strongly expressed in apiculi and stigmas, respectively. OsC1 specifically interacts with OsPa or OsPs to activate OsDFR and other anthocyanin biosynthesis genes, resulting in purple-colored apiculi or stigmas. OsC1 itself does not produce color but can produce brown apiculi when functioning together with OsPa. Loss of function of OsDFR alone leads to brown apiculi and straw-white stigmas. Genotyping and phenotyping of a panel of 176 rice accessions revealed diverse genotypic combinations of OsC1, OsDFR, OsPa and OsPs that enable accurate prediction of their apiculus and stigma pigmentation phenotypes, thus validating the general applicability of the OsC1-OsDFR-OsPa and OsC1-OsDFR-OsPs models to natural populations. Our findings disclosed the biological functions of OsC1, OsPa and OsPs, and shed light on the specific regulatory systems of anthocyanin biosynthesis in apiculi and stigmas, a further step in understanding the regulatory network of anthocyanin biosynthesis in rice.

16.
J Mol Graph Model ; 104: 107842, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33529934

RESUMO

To study the binding mechanism of 4',6-diamidino-2-phenylindole (DAPI) and polyphosphate (Poly-P) and find fluorescent dyes which can dye Poly-P better, the interaction model of DAPI and Poly-P was calculated by the self-consistent-charge, density functional tight-binding (SCC-DFTB-D) method, and the binding sites of DAPI and Poly-P were analyzed. Further, Cy3, Rhodamine 6G and Fluorescein, which are structurally similar to DAPI, were selected to analyze their interactions with Poly-P. The binding energies and frontier orbital properties of the complexes were analyzed. These four fluorescent dyes were further used to dye the activated sludge smear and observe the fluorescence property. The Simulation results show that the N-containing indole ring structures in DAPI plays an important role in the interaction with Poly-P; the binding energies for DAPI, Cy3, Rhodamine 6G and Fluorescein with Poly-P are -42.6, -165.4, -34.7 and -28.9 kcal/mol, respectively. The frontier orbital properties for the complexes were studied, which further indicates that the interactions between Cy3, Rhodamine 6G and Poly-P are stronger than that of Fluorescein and Poly-P. The experimental results showed that Cy3 had excellent dyeing effect on Poly-P and could recognize them, while Fluorescein could not dye Poly-P. The experimental results were in good agreement with those predicted by simulation, which verified the correctness of our calculation method and provided a new strategy for finding more reliable, more sensitive and more economical fluorescent dyes capable of dyeing Poly-P.


Assuntos
Corantes Fluorescentes , Polifosfatos , Sítios de Ligação , Espectrometria de Fluorescência
17.
Virus Res ; 288: 198111, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32791169

RESUMO

In this paper, a basic fractional-order model is proposed to describe the transmission of African swine fever. Two cases are considered: constant control and optimal control. In the former case, the existence and uniqueness of positive solution is proved firstly; then the basic reproduction number and the sufficient conditions for the stability of two equilibriums are obtained by using the next generation matrix method and Lyapunov LaSalle's invariance principle. In the latter case, optimal control is considered. By using the Hamiltonian function and Pontryagin's maximum principle, the optimal control formula is obtained. In addition, some examples and numerical simulations (based on Adama-Bashforth-Moulton predictor-corrector method) are performed to verify the theoretical results. At last, we present some brief discussion and conclusion.


Assuntos
Febre Suína Africana/transmissão , Febre Suína Africana/virologia , Modelos Teóricos , Animais , Número Básico de Reprodução , Humanos , Suínos
18.
J Mol Graph Model ; 100: 107663, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32659629

RESUMO

A series of novel antifolates (32 compounds) were used to study the interactions with folate receptors α and ß. The compounds had different sizes of methyl (-CH3), carboxyl (-COOH), hydroxyl (-OH), and amino groups (-NH2). The binding properties of the complexes were studied by molecular docking, molecular dynamic (MD) simulations, and MM/PBSA free energy calculations. The docked binding energies and modes were analyzed to identify compounds with good recognition of FRα from FRß. The stable conformers, root mean square displacement, root mean square fluctuation free binding energy, and contribution of residues to the binding energy of the complexes were further analyzed to illustrate the interactions between the novel compounds and folate receptors. The data show that introducing long functional groups in folate will increase the binding affinity with FRα but will decrease the binding affinity with FRß. The results provide a strategy for the design of novel antifolates targeted to FRα.


Assuntos
Antagonistas do Ácido Fólico , Ácido Fólico , Antagonistas do Ácido Fólico/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular
19.
J Mol Model ; 26(6): 162, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32474655

RESUMO

Taxanes (paclitaxel, docetaxel, cabazitaxel) are anticancer drugs as microtubule inhibitors. Following our previous studies on paclitaxel and docetaxel, in this work, we examine cabazitaxel and compare these three taxenes. The binding interaction of three taxanes with various ß-tubulin isotypes is studied by homology modeling, molecular docking, and molecular dynamics simulations. The results show that the effects of docetaxel on ßI-tubulin (- 29.5 kcal/mol) and of paclitaxel on ßIIa-tubulin (- 25.5 kcal/mol) are much stronger than their effects on ßIII-tubulin (- 17.8 kcal/mol and - 8.6 kcal/mol, respectively). However, the effect of cabazitaxel on ßIII-tubulin (- 23.0 kcal/mol) is comparable with that on ßI-tubulin (- 24.0 kcal/mol) and ßIIa-tubulin (- 25.9 kcal/mol), consistent with the fact that overexpression of ßIII-tubulin increases the drug resistance to paclitaxel and docetaxel, but has little influence for cabazitaxel. This theoretical research supports the use of cabazitaxel for patients who are resistant to the action of paclitaxel and docetaxel.


Assuntos
Taxoides/farmacologia , Tubulina (Proteína)/metabolismo , Antineoplásicos/farmacologia , Docetaxel/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Microtúbulos/efeitos dos fármacos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Paclitaxel/farmacologia , Termodinâmica , Moduladores de Tubulina/farmacologia
20.
Sci Rep ; 10(1): 420, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31942006

RESUMO

Emphysematous smokers with normal spirometry form a considerable proportion of the clinical population. However, despite presenting with respiratory symptoms and activity limitation, they cannot be diagnosed with chronic obstructive lung disease (COPD) according to current criteria. Thus, we aimed to determine whether emphysema in smokers has a different pathogenesis from that in patients with COPD. We compared 12 pairs of lung tissue samples from emphysematous patients with normal spirometry and COPD, and determined the degree of emphysema using computed tomography. With a focus on COPD-related pathogenesis, we independently assessed inflammatory response, protease-antiprotease balance, oxidative stress, and apoptosis in both groups. Both groups showed similar pathological changes at a comparable degree of emphysema; the expression of inflammatory factors was comparable, with overexpression of proteases and decreased levels of antiproteases. Moreover, there was no significant difference in the activities of glutathione and superoxide dismutase, and expression of apoptosis-related factors. In conclusion, emphysema in smokers with normal spirometry and in patients with COPD had similar pathogenesis. Forced expiratory volume in 1 second cannot be used as the sole diagnostic criterion in patients with COPD; early intervention is of great importance to such patients.


Assuntos
Enfisema/fisiopatologia , Inflamação/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/fisiopatologia , Fumantes/estatística & dados numéricos , Fumar/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Enfisema/induzido quimicamente , Feminino , Volume Expiratório Forçado , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Testes de Função Respiratória , Espirometria
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