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1.
Opt Express ; 32(2): 2257-2270, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297760

RESUMO

The high-speed gaze and high resolution are critical factors for actual monitoring systems. However, the conventional method cannot track and zoom as fast as expected due to the larger inertia and it results in a low resolution due to the digital zoom. In this paper, we proposed a high-speed tracking and zooming optics that is coaxial designed and with an active tracking unit and an optical zooming unit to overcome the above issues. The tracking unit always tracks the object in the center of view by a pan-tilt mirror controller and a visual feedback tracking algorithm within 4 milliseconds response order. The zooming unit can continuously change the magnification from 1X to 2X by three liquid lenses within milliseconds. Besides, the zooming unit provides a compensation algorithm to achieve accurate zoom and focus.

2.
J Opt Soc Am A Opt Image Sci Vis ; 41(3): 468-475, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437438

RESUMO

Dynamic projection mapping for moving objects has attracted much attention in recent years. However, conventional approaches have faced some issues, such as the target objects being limited to the moving speed of the objects, the limitation of the narrow depth-of-field optics, and the planar shape objects. This work proposed an adaptive three-dimensional projection prototype, and it could project an always in-focus image on a non-planar object based on liquid lens optics. The location of the non-planar object could be detected, and the mapped projection contents calculated; as a result, a stable "printed" projection mapping should be viewed on a moving object.

3.
J Org Chem ; 87(12): 7665-7672, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35647791

RESUMO

To explore the reaction universality of bridge nitration, the mononitration of different p-tert-butylcalix[4]arene derivatives was executed with tert-butyl nitrite as a nitration reagent. The effects of calix[4]arene conformations, substituents on the lower rim, and reaction conditions on bridge mononitration are systematically studied. The bridge nitration of p-tert-butylcalix[4]arene derivatives in 1,3-alternate, 1,2-alternate, and partial cone conformations can be smoothly executed while that of p-tert-butylcalix[4]arene derivatives strictly regulated in a cone conformation cannot. The nitration product complexity shows a positive correlation with the bridge-hydrogen types, and the optimal bridge-mononitrated substrate is calix[4]arene with only one bridge-hydrogen type. The electron-withdrawing substituent on the lower rim is apparently beneficial for the bridge mononitration. As a result, a variety of bridging chiral p-tert-butylcalix[4]arenes with a mononitro bridge substituent have been successfully synthesized. The highest bridge-mononitrated yield can reach 27% from 1,3-alternate p-tert-butylcalix[4]arene biscrown-5 under optimal reaction conditions.

4.
Mar Drugs ; 20(3)2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35323513

RESUMO

Two new cyclized thiolopyrrolone derivatives, namely, thiolopyrrolone A (1) and 2,2-dioxidothiolutin (2), together with the kn own compound, thiolutin (3) were identified from a marine-derived Streptomyces sp. BTBU20218885, which was isolated from a mud sample collected from the coastal region of Xiamen, China. Their chemical structures were determined using spectroscopic data, including HRESIMS, 1D and 2D NMR techniques. 1 possessed a unique unsymmetrical sulfur-containing thiolopyrrolone structure. All the compounds were tested for bioactivities against Staphylococcus aureus, Escherichia coli, Bacille Calmette-Guérin (BCG), Mycobacterium tuberculosis, and Candida albicans. 1 displayed antibacterial activities against BCG, M. tuberculosis, and S. aureus with minimum inhibitory concentration (MIC) values of 10, 10, and 100 µg/mL, respectively. Thiolutin (3) showed antibacterial activities against E. coli, BCG, M. tuberculosis, and S. aureus with MIC values of 6.25, 0.3125, 0.625, and 3.125 µg/mL, respectively.


Assuntos
Anti-Infecciosos , Organismos Aquáticos/química , Produtos Biológicos , Pirróis , Streptomyces/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Organismos Aquáticos/genética , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Ciclização , Testes de Sensibilidade Microbiana , Pirróis/química , Pirróis/isolamento & purificação , Pirróis/farmacologia , Streptomyces/genética
5.
J Org Chem ; 86(5): 3952-3959, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577735

RESUMO

In order to prepare bridging chiral p-tert-butylcalix[4]crown-5 with a mononitro bridge substituent in a 1,3-alternate conformation, a mononitration method of calix[4]arene bridging methylene has been first developed with tert-butyl nitrite as a nitration reagent. The effects of solvent, reaction temperature, reaction time, and nitration reagent dosage on bridge mononitration have been deeply explored to obtain an optimal nitration condition. The facile nitration presents a new key for calix[4]arene bridge derivatization. After further modification and diastereoisomeric resolution, a pair of bridging chiral p-tert-butylcalix[4]arenes with a monoamino bridge substituent were produced from the bridge-mono-nitrated calix[4]arene. Their preliminary catalysis results in the Henry reaction show good catalytic activities (up to 95% yield) and still low but obviously enhanced enantioselectivities (up to 22.3% ee from 7a, 6% ee from 1), which confirms that the structural transformation indeed improves asymmetric catalysis performances of bridging chiral calix[4]crown-5 amines in a 1,3-alternate conformation.

6.
J Nat Prod ; 84(5): 1556-1562, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33914536

RESUMO

Longipetalol A (1) is an unprecedented highly modified triterpenoid with a unique 1,2-seco-3-(2-oxo-phenylethyl)-17α-13,30-cyclodammarane skeleton, featuring an acetal-lactone fragment. It was isolated from Dichapetalum longipetalum along with two additional derivatives, namely, longipetalols B (2) and C (3). Their structures were elucidated using spectroscopic analyses combined with single-crystal X-ray diffraction. Compounds 1, 2, and 3 exhibited inhibitory effects on nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Magnoliopsida/química , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , China , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Fitoquelatinas/isolamento & purificação , Fitoquelatinas/farmacologia , Células RAW 264.7 , Triterpenos/isolamento & purificação
7.
J Org Chem ; 84(18): 11774-11782, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31454244

RESUMO

Triarylmethanol adopts a propeller-shaped conformation with either right-handed (P) or left-handed (M) configuration. Herein, new triarylmethanols with two chiral centers were obtained via introduction of two cis-hydroxyl groups on the side chains, affording four stereoisomers. These four stereoisomers were easily separated by silica gel column chromatography into two pairs of propeller-shaped enantiomers, as shown by NMR and X-ray crystallographic studies. High-performance liquid chromatography (HPLC) studies showed that the configurations of the hydroxyl-bearing triarylmethanols are much more stable than those of the bulky tert-butyldimethylsilyl-protected precursors, inconsistent with the general strategy in which the steric repulsion is largely responsible for the configurational stability. Similarly, two hydroxyl-bearing tetrathiatriarylmethyl (TAM) radicals also exhibit excellent configurational stability and are thus separable by CS-HPLC into four stereoisomers. Interestingly, both helical chirality from triaryl group (M or P) and central chirality (R and S) on the side chain have little effect on their electron paramagnetic resonance properties. Our present study provides a new strategy to construct configurationally stable triaryl compounds and demonstrates that the side chain on TAM radicals is a new site for their structural modifications.

8.
J Org Chem ; 81(22): 10683-10687, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27786466

RESUMO

A novel efficient approach to optically pure bridging chiral calix[4]arenes through a homologous anionic ortho-Fries rearrangement of inherently chiral calix[4]arenes was presented for the first time. As a result, two pairs of N,N'-dimethylformamidyl-substituted bridging chiral p-tert-butylcalix[4]arene enantiomers were facilely obtained. Their absolute configurations were determined through ROESY analysis, ECD comparison, and X-ray crystallographic analysis.

9.
Mol Ther ; 23(12): 1867-76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26403887

RESUMO

Recombinant adeno-associated virus serotype 3B (rAAV3B) can transduce cultured human liver cancer cells and primary human hepatocytes efficiently. Serine (S)- and threonine (T)-directed capsid modifications further augment its transduction efficiency. Systemically delivered capsid-optimized rAAV3B vectors can specifically target cancer cells in a human liver cancer xenograft model, suggesting their potential use for human liver-directed gene therapy. Here, we compared transduction efficiencies of AAV3B and AAV8 vectors in cultured primary human hepatocytes and cancer cells as well as in human and mouse hepatocytes in a human liver xenograft NSG-PiZ mouse model. We also examined the safety and transduction efficacy of wild-type (WT) and capsid-optimized rAAV3B in the livers of nonhuman primates (NHPs). Intravenously delivered S663V+T492V (ST)-modified self-complementary (sc) AAV3B-EGFP vectors led to liver-targeted robust enhanced green fluorescence protein (EGFP) expression in NHPs without apparent hepatotoxicity. Intravenous injections of both WT and ST-modified rAAV3B.ST-rhCG vectors also generated stable super-physiological levels of rhesus chorionic gonadotropin (rhCG) in NHPs. The vector genome predominantly targeted the liver. Clinical chemistry and histopathology examinations showed no apparent vector-related toxicity. Our studies should be important and informative for clinical development of optimized AAV3B vectors for human liver-directed gene therapy.


Assuntos
Dependovirus/genética , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos , Neoplasias Hepáticas/genética , Transdução Genética , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Linhagem Celular Tumoral , Modelos Animais de Doenças , Terapia Genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Hepatócitos/metabolismo , Humanos , Fígado/citologia , Neoplasias Hepáticas/terapia , Macaca mulatta , Camundongos , Transplante de Neoplasias
10.
Mol Ther ; 22(7): 1299-1309, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24781136

RESUMO

Some recombinant adeno-associated viruses (rAAVs) can cross the neonatal blood-brain barrier (BBB) and efficiently transduce cells of the central nervous system (CNS). However, in the adult CNS, transduction levels by systemically delivered rAAVs are significantly reduced, limiting their potential for CNS gene therapy. Here, we characterized 12 different rAAVEGFPs in the adult mouse CNS following intravenous delivery. We show that the capability of crossing the adult BBB and achieving widespread CNS transduction is a common character of AAV serotypes tested. Of note, rAAVrh.8 is the leading vector for robust global transduction of glial and neuronal cell types in regions of clinical importance such as cortex, caudate-putamen, hippocampus, corpus callosum, and substantia nigra. It also displays reduced peripheral tissue tropism compared to other leading vectors. Additionally, we evaluated rAAVrh.10 with and without microRNA (miRNA)-regulated expressional detargeting from peripheral tissues for systemic gene delivery to the CNS in marmosets. Our results indicate that rAAVrh.8, along with rh.10 and 9, hold the best promise for developing novel therapeutic strategies to treat neurological diseases in the adult patient population. Additionally, systemically delivered rAAVrh.10 can transduce the CNS efficiently, and its transgene expression can be limited in the periphery by endogenous miRNAs in adult marmosets.


Assuntos
Sistema Nervoso Central/metabolismo , Dependovirus/genética , Animais , Encéfalo/metabolismo , Callithrix , Masculino , Camundongos , MicroRNAs/genética , Primatas
11.
Int J Mol Sci ; 15(6): 9844-58, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24897021

RESUMO

For all microhelices on aromatic rings of inherently chiral calix[4]arene, an expression was derived from one approximation and one hypothesis on the basis of the electron-on-a-helix model of Tinoco and Woody as follows: 1/E = µ(H - KΔα2), where µ = 1 for the right-handed microhelix and µ = -1 for the left-handed microhelix; and H and K are constant and greater than zero. The expression correlates microhelical electronic energy (E) with the atom polarizability difference (Δα) on both microhelix ends, which intuitively and clearly shows the impact of helical substituent polarizability on helical electronic energy. The case analysis almost entirely proves that the qualitative analysis of the helical electronic energy of inherently chiral calix[4]arenes with the expression is scientific and can be used to effectively assign their absolute configuration.


Assuntos
Calixarenos/química , Elétrons , Fenóis/química , Modelos Moleculares , Conformação Molecular , Estereoisomerismo
12.
Phytochemistry ; 217: 113900, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37898415

RESUMO

A phytochemical research on the twigs of Dichapetalum longipetalum (Turcz.) Engl. Resulted in five undescribed dichapetalin-type triterpenoids 1-5. Their chemical structures were determined by spectroscopic analysis of HR-ESIMS and NMR spectra and the absolute configuration of compound 1 was completely elucidated by single crystal X-ray crystallography. Through preliminary anti-inflammatory activity assessment, compound 1 exhibited inhibitory effect on LPS-induced NO production in RAW264.7 murine macrophages with an IC50 value of 2.09 µM.


Assuntos
Triterpenos , Animais , Camundongos , Triterpenos/farmacologia , Triterpenos/química , Macrófagos , Extratos Vegetais/química , Espectroscopia de Ressonância Magnética , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Estrutura Molecular
13.
Hepatology ; 56(6): 2094-105, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22806830

RESUMO

UNLABELLED: Hepatitis C virus (HCV)-specific immune effector responses can cause liver damage in chronic infection. Hepatic stellate cells (HSC) are the main effectors of liver fibrosis. TGFß, produced by HCV-specific CD8(+) T cells, is a key regulatory cytokine modulating HCV-specific effector T cells. Here we studied TGFß as well as other factors produced by HCV-specific intrahepatic lymphocytes (IHL) and peripheral blood cells in hepatic inflammation and fibrogenesis. This was a cross-sectional study of two well-defined groups of HCV-infected subjects with slow (≤ 0.1 Metavir units/year, n = 13) or rapid (n = 6) liver fibrosis progression. HCV-specific T-cell responses were studied using interferon-gamma (IFNγ)-ELISpot ±monoclonal antibodies (mAbs) blocking regulatory cytokines, along with multiplex, enzyme-linked immunosorbent assay (ELISA) and multiparameter fluorescence-activated cell sorting (FACS). The effects of IHL stimulated with HCV-core peptides on HSC expression of profibrotic and fibrolytic genes were determined. Blocking regulatory cytokines significantly raised detection of HCV-specific effector (IFNγ) responses only in slow fibrosis progressors, both in the periphery (P = 0.003) and liver (P = 0.01). Regulatory cytokine blockade revealed HCV-specific IFNγ responses strongly correlated with HCV-specific TGFß, measured before blockade (R = 0.84, P = 0.0003), with only a trend to correlation with HCV-specific IL-10. HCV-specific TGFß was produced by CD8 and CD4 T cells. HCV-specific TGFß, not interleukin (IL)-10, inversely correlated with liver inflammation (R = -0.63, P = 0.008) and, unexpectedly, fibrosis (R = -0.46, P = 0.05). In addition, supernatants from HCV-stimulated IHL of slow progressors specifically increased fibrolytic gene expression in HSC and treatment with anti-TGFß mAb abrogated such expression. CONCLUSION: Although TGFß is considered a major profibrogenic cytokine, local production of TGFß by HCV-specific T cells appeared to have a protective role in HCV-infected liver, together with other T-cell-derived factors, ameliorating HCV liver disease progression.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Hepacivirus/imunologia , Células Estreladas do Fígado/metabolismo , Hepatite C Crônica/metabolismo , Cirrose Hepática/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Estudos Transversais , Progressão da Doença , Feminino , Expressão Gênica , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Fígado/imunologia , Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Metaloproteinase 1 da Matriz/genética , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Proteínas do Core Viral/imunologia
14.
J Biomol Struct Dyn ; 41(24): 15411-15420, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37126536

RESUMO

Obesity has emerged as a global issue, but with the complex structures of multiple related important targets and their agonists or antagonists determined, the mechanism of ligand-protein interaction may offer new chances for developing new generation agonists anti-obesity. Based on the molecule surface of the cryo-EM protein structure 7AUE, we tried to replace D-Ala3 with D-Met in setmelanotide as the linker site for fragment-growing with De novo evolution. The simulation results indicate that the derivatives could improve the binding abilities with the melanocortin 4 receptor and the selectivity over the melanocortin 1 receptor. The improved selectivity of the newly designed derivatives is mainly due to the shape difference of the molecular surface at the orthosteric peptide-binding pocket between melanocortin 4 receptor and melanocortin 1 receptor. The new extended fragments could not only enhance the binding affinities but also function as a gripper to seize the pore, making it easier to balance and stabilize the other component of the new derivatives. Although it is challenging to synthesize the compounds designed in silico, this study may perhaps serve as a trigger for additional anti-obesity research.Communicated by Ramaswamy H. Sarma.


Assuntos
Receptor Tipo 1 de Melanocortina , Receptor Tipo 4 de Melanocortina , Humanos , Simulação de Acoplamento Molecular , Receptor Tipo 4 de Melanocortina/agonistas , Receptor Tipo 4 de Melanocortina/metabolismo , alfa-MSH/química , alfa-MSH/metabolismo , Obesidade
15.
J Biol Chem ; 286(4): 2665-74, 2011 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-21098019

RESUMO

HIV/HCV coinfection leads to accelerated hepatic fibrosis progression, with higher rates of cirrhosis, liver failure, and liver death than does HCV mono-infection. However, the profibrogenic role of HIV on hepatocytes and hepatic stellate cells (HSC) has not been fully clarified. We hypothesized that HIV, HCV induce liver fibrosis through altered regulation of the production of extracellular matrix and matrix metalloproteinases. We examined the fibrogenesis- and fibrolysis-related gene activity in LX2 HSC and Huh7.5.1 cells in the presence of inactivated CXCR4 and CCR5 HIV, as well as HCV JFH1 virus. The role of reactive oxygen species (ROS) upon fibrosis gene expression was assessed using the ROS inhibitor. Fibrosis-related transcripts including procollagen α1(I) (CoL1A), TIMP1, and MMP3 mRNA were measured by qPCR. TIMP1 and MMP3 protein expression were assessed by ELISA. We found that inactivated CXCR4 HIV and CCR5 HIV increased CoL1A, and TIMP1 expression in both HSC and Huh7.5.1 cells; the addition of JFH1 HCV further increased CoL1A and TIMP1 expression. CXCR4 HIV and CCR5 HIV induced ROS production in HSC and Huh7.5.1 cells which was further enhanced by JFH1 HCV. The ROS inhibitor DPI abrogated HIV-and HCV-induced CoL1A and TIMP1 expression. HIV and HCV-induced CoL1A and TIMP1 expression were also blocked by NFκB siRNA. Our data provide further evidence that HIV and HCV independently regulate hepatic fibrosis progression through the generation of ROS; this regulation occurs in an NFκB-dependent fashion. Strategies to limit the viral induction of oxidative stress are warranted to inhibit fibrogenesis.


Assuntos
Infecções por HIV , HIV/metabolismo , Hepacivirus/metabolismo , Hepatite C , Cirrose Hepática , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Infecções por HIV/complicações , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Hepatite C/complicações , Hepatite C/metabolismo , Hepatite C/patologia , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/virologia , Estresse Oxidativo
16.
Gastroenterology ; 140(5): 1642-52, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21277850

RESUMO

BACKGROUND & AIMS: The ubiquitous cross-linking enzyme tissue transglutaminase (TG2) has been implicated in irreversible collagen stabilization in liver fibrosis, although functional evidence is lacking. We studied the contribution of TG2 to hepatic fibrotic matrix stability, as well as liver fibrosis progression and regression in TG2-deficient mice. METHODS: Advanced liver fibrosis was induced by carbon tetrachloride or thioacetamide in TG2(-/-) mice and their wild-type littermates to study fibrosis progression and its spontaneous regression for up to 36 weeks. Pattern and extent of fibrosis were analyzed by histology and hepatic hydroxyproline quantification. Dynamic changes in hepatic matrix cross-linking were assessed by stepwise collagen extraction. Expression of 7 TGs and fibrosis-related genes was determined by quantitative reverse-transcription polymerase chain reaction. RESULTS: Transglutaminase activity was increased in fibrosis, and the level of TG2 messenger RNA correlated with the expression of fibrosis-related genes. Biochemical analysis revealed progressive collagen stabilization, with an up to 6-fold increase in the highly cross-linked, pepsin-insoluble fraction (26%). In TG2(-/-) mice, hepatic TG activity was significantly decreased, but chronic administration of carbon tetrachloride or thioacetamide led to a comparable extent and pattern of liver fibrosis, as in wild-type mice. In TG2(-/-) mice, the composition of hepatic collagen fractions and levels of fibrosis-related transcripts were unchanged, and fibrosis reversal was not facilitated. CONCLUSIONS: TG2 and TG activity are up-regulated during hepatic fibrosis progression, but do not contribute to fibrogenesis or stabilization of the collagen matrix. TG2 deletion does not promote regression of liver fibrosis. TG2-independent collagen cross-linking is a remarkable feature of progressing hepatic fibrosis and represents an important therapeutic target for liver fibrosis.


Assuntos
Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica , Cirrose Hepática Experimental/enzimologia , Fígado/patologia , RNA/genética , Transglutaminases/genética , Animais , Apoptose/genética , Progressão da Doença , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Proteínas de Ligação ao GTP/biossíntese , Fígado/enzimologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína 2 Glutamina gama-Glutamiltransferase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transglutaminases/biossíntese
17.
Comb Chem High Throughput Screen ; 25(9): 1450-1461, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34182904

RESUMO

BACKGROUND: The Peroxisome Proliferator-Activated Receptors (PPARs) are ligandactivated transcription factors belonging to the nuclear receptor family. The roles of PPARα in fatty acid oxidation and PPARγ in adipocyte differentiation and lipid storage have been widely characterized. Compounds with dual PPARα/γ activity have been proposed, combining the benefits of insulin sensitization and lipid lowering into one drug, allowing a single drug to reduce hyperglycemia and hyperlipidemia while preventing the development of cardiovascular complications. METHODS: The new PPARα/γ agonists were screened through virtual screening of pharmacophores and molecular dynamics simulations. First, in the article, the constructed pharmacophore was used to screen the Ligand Expo Components-pub database to obtain the common structural characteristics of representative PPARα/γ agonist ligands. Then, the accepted ligand structure was modified and replaced to obtain 12 new compounds. Using molecular docking, ADMET and molecular dynamics simulation methods to screen the designed 12 ligands, analyze their docking scores when they bind to the PPARα/γ dual targets, their stability and pharmacological properties when they bind to the PPARα/γ dual targets. RESULTS: We performed pharmacophore-based virtual screening for 22949 molecules in Ligand Expo Components-pub database. The compounds that were superior to the original ligand were performed structural analysis and modification, and a series of compounds with novel structures were designed. Using precise docking, ADMET prediction and molecular dynamics methods to screen and verify newly designed compounds, and the above compounds show higher docking scores and lower side effects. CONCLUSION: 9 new PPARα/γ agonists were obtained by pharmacophore modeling, docking analysis and molecular dynamics simulation.


Assuntos
Simulação de Dinâmica Molecular , PPAR alfa , Ligantes , Lipídeos , Simulação de Acoplamento Molecular , PPAR alfa/agonistas , PPAR gama/agonistas
18.
Virology ; 574: 1-8, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35858511

RESUMO

HIV-1 remains one of the most devastating infectious pathogens without available vaccines. A valid neutralization assay using multiple representative virus strains is prerequisite for antibody response analysis in HIV-1 vaccine development, where HIV pseudoviruses (PsVs) commonly serve as surrogate agents for the authentic HIV, offering a safer manipulation in Biosafety Level 2+. However, PsV production is of low efficiency and is unstable in this field. Here, we optimize PsV production conditions via the use of alternative host cells, packaging ratios and gene truncation. We show that a 153-aa truncation of the endodomain substantially enhances the packaging efficiency of HIV PsVs, providing 4 to 25 times higher infection titers than the full-length Env. Further, we obtained a robust HIV-1 PsV panel covering 12 representative global strains for neutralization assay testing. This work sheds light on how to optimize HIV PsV packaging, and provides functional insight into the cytoplasmic domain of HIV-1.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Neutralizantes , Anticorpos Anti-HIV , HIV-1/genética , Humanos , Testes de Neutralização
19.
Vaccine ; 40(47): 6839-6848, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36253220

RESUMO

The ongoing coronavirus disease-19 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has drastically changed our way of life and continues to have an unmitigated socioeconomic impact across the globe. Research into potential vaccine design and production is focused on the spike (S) protein of the virus, which is critical for virus entry into host cells. Yet, whether the degree of glycosylation in the S protein is associated with vaccine efficacy remains unclear. Here, we first optimized the expression of the S protein in mammalian cells. While we found no significant discrepancy in purity, homogeneity, or receptor binding ability among S proteins derived from 293F cells (referred to as 293F S-2P), 293S GnTI- cells (defective in N-acetylglucosaminyl transferase I enzyme; 293S S-2P), or TN-5B1-4 insect cells (Bac S-2P), there was significant variation in the glycosylation patterns and thermal stability of the proteins. Compared with the partially glycosylated 293S S-2P or Bac S-2P, the fully glycosylated 293F S-2P exhibited higher binding reactivity to convalescent sera. In addition, 293F S-2P induced higher IgG and neutralizing antibody titres than 293S or Bac S-2P in mice. Furthermore, a prime-boost-boost regimen, using a combined immunization of S-2P proteins with various degrees of glycosylation, elicited a more robust neutralizing antibody response than a single S-2P alone. Collectively, this study provides insight into ways to design a more effective SARS-CoV-2 immunogen.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Camundongos , Animais , SARS-CoV-2 , Glicosilação , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Anticorpos Antivirais , Mamíferos/metabolismo , Soroterapia para COVID-19
20.
Analyst ; 136(3): 520-6, 2011 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-21109888

RESUMO

Dye conjugation is a common strategy improving the surface enhanced Raman detection sensitivity of biomolecules. Reported is a proof-of-concept study of a novel surface enhanced Raman spectroscopic tagging strategy termed as acid-cleavable SERS tag (ACST) method. Using Rhodamine B as the starting material, we prepared the first ACST prototype that consisted of, from the distal end, a SERS tag moiety (STM), an acid-cleavable linker, and a protein reactive moiety. Complete acid cleavage of the ACST tags was achieved at a very mild condition that is 1.5% trifluoroacetic acid (TFA) aqueous solution at room temperature. SERS detection of this ACST tagged protein was demonstrated using bovine serum albumin (BSA) as the model protein. While the SERS spectrum of intact ACST-BSA was entirely dominated by the fluorescent signal of STM, quality SERS spectra can be readily obtained with the acid cleaved ACST-BSA conjugates. Separation of the acid cleaved STM from protein further enhances the SERS sensitivity. Current SERS detection sensitivity, achieved with the acid cleaved ACST-BSA conjugate is ∼5 nM in terms of the BSA concentration and ∼1.5 nM in ACST content. The dynamic range of the cleaved ACST-BSA conjugate spans four orders of magnitudes from ∼10 nM to ∼100 µM in protein concentrations. Further improvement in the SERS sensitivity can be achieved with resonance Raman acquisition. This cleavable tagging strategy may also be used for elimination of protein interference in fluorescence based biomolecule detection.


Assuntos
Corantes Fluorescentes/química , Proteínas/análise , Rodaminas/química , Análise Espectral Raman/métodos , Ácido Trifluoracético/química , Eletroforese em Gel de Poliacrilamida , Estrutura Molecular , Sensibilidade e Especificidade , Soroalbumina Bovina/análise , Especificidade por Substrato
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