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1.
Nat Commun ; 15(1): 4330, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773072

RESUMO

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Microscopia Crioeletrônica , Infecções por Henipavirus , Proteínas Virais de Fusão , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Anticorpos Antivirais/imunologia , Infecções por Henipavirus/virologia , Infecções por Henipavirus/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais de Fusão/química , Humanos , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/química , Vírus Nipah/imunologia , Internalização do Vírus/efeitos dos fármacos , Henipavirus/imunologia , Cricetinae , Reações Cruzadas/imunologia , Vírus Hendra/imunologia , Macaca , Mesocricetus , Cristalografia por Raios X
2.
Fitoterapia ; 175: 105957, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604260

RESUMO

Curcuma wenyujin (C. wenyujin) is a medicinal plant that is traditionally used to treat blood stagnation, liver fibrosis, pain, and jaundice. In this study, we examined the effect of C. wenyujin rhizome extract on hepatic lipid accumulation both in vivo and in vitro. We found that the petroleum ether fraction of C. wenyujin rhizome extract (CWP) considerably reduced the accumulation of lipids in HepG2 cells treated with oleic and palmitic acid. Ultra-high-performance liquid chromatography coupled with LTQ-Orbitrap mass spectrometry was used to analyze the main chemical constituents of CWP, and 21 sesquiterpenes were identified. In vivo experiments revealed that the administration of CWP significantly reduced the body weight and serum total cholesterol (TC) level of low-density-lipoprotein receptor knockout mice treated with a high-fat diet without affecting their food intake. CWP also significantly reduced the levels of liver TC, liver triglycerides, aspartate transaminase, and alanine transaminase. Histological examination revealed that CWP dose-dependently reduced steatosis in liver tissue, significantly downregulated the expression of lipogenesis genes, and increased the ß-oxidation of fatty acids. CWP also significantly increased autophagy-related proteins. In conclusion, CWP rich in sesquiterpenes reduces the accumulation of lipids in vivo and in vitro by improving lipid metabolism and activating autophagy.


Assuntos
Curcuma , Metabolismo dos Lipídeos , Camundongos Knockout , Extratos Vegetais , Rizoma , Sesquiterpenos , Curcuma/química , Rizoma/química , Animais , Humanos , Camundongos , Células Hep G2 , Extratos Vegetais/farmacologia , Sesquiterpenos/farmacologia , Sesquiterpenos/isolamento & purificação , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Colesterol/sangue , Colesterol/metabolismo , Dieta Hiperlipídica , Receptores de LDL/metabolismo , Receptores de LDL/genética , Estrutura Molecular
3.
Front Immunol ; 14: 1239179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868993

RESUMO

Introduction: The SARS-CoV-2 Omicron variant has become the dominant SARS-CoV-2 variant and exhibits immune escape to current COVID-19 vaccines, the further boosting strategies are required. Methods: We have conducted a non-randomized, open-label and parallel-controlled phase 4 trial to evaluate the magnitude and longevity of immune responses to booster vaccination with intramuscular adenovirus vectored vaccine (Ad5-nCoV), aerosolized Ad5-nCoV, a recombinant protein subunit vaccine (ZF2001) or homologous inactivated vaccine (CoronaVac) in those who received two doses of inactivated COVID-19 vaccines. Results: The aerosolized Ad5-nCoV induced the most robust and long-lasting neutralizing activity against Omicron variant and IFNg T-cell response among all the boosters, with a distinct mucosal immune response. SARS-CoV-2-specific mucosal IgA response was substantially generated in subjects boosted with the aerosolized Ad5-nCoV at day 14 post-vaccination. At month 6, participants boosted with the aerosolized Ad5-nCoV had remarkably higher median titer and seroconversion of the Omicron BA.4/5-specific neutralizing antibody than those who received other boosters. Discussion: Our findings suggest that aerosolized Ad5-nCoV may provide an efficient alternative in response to the spread of the Omicron BA.4/5 variant. Clinical trial registration: https://www.chictr.org.cn/showproj.html?proj=152729, identifier ChiCTR2200057278.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Imunidade nas Mucosas , Anticorpos
4.
Signal Transduct Target Ther ; 7(1): 139, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35478188

RESUMO

The SARS-CoV-2 Omicron variant shows substantial resistance to neutralization by infection- and vaccination-induced antibodies, highlighting the demands for research on the continuing discovery of broadly neutralizing antibodies (bnAbs). Here, we developed a panel of bnAbs against Omicron and other variants of concern (VOCs) elicited by vaccination of adenovirus-vectored COVID-19 vaccine (Ad5-nCoV). We also investigated the human longitudinal antibody responses following vaccination and demonstrated how the bnAbs evolved over time. A monoclonal antibody (mAb), named ZWD12, exhibited potent and broad neutralization against SARS-CoV-2 variants Alpha, Beta, Gamma, Kappa, Delta, and Omicron by blocking the spike protein binding to the angiotensin-converting enzyme 2 (ACE2) and provided complete protection in the challenged prophylactic and therapeutic K18-hACE2 transgenic mouse model. We defined the ZWD12 epitope by determining its structure in complex with the spike (S) protein via cryo-electron microscopy. This study affords the potential to develop broadly therapeutic mAb drugs and suggests that the RBD epitope bound by ZWD12 is a rational target for the design of a broad spectrum of vaccines.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais/genética , Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19/prevenção & controle , Vacinas contra COVID-19/genética , Microscopia Crioeletrônica , Epitopos , Humanos , Camundongos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinação , Proteínas do Envelope Viral
5.
Int J Anal Chem ; 2021: 5524361, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567122

RESUMO

OBJECTIVE: To develop a new method for quantitatively analyzing six tyrosine kinase inhibitors (gefitinib, erlotinib, icotinib, afatinib, osimertinib, and crizotinib) used in the treatment of non-small cell lung cancer (NSCLC) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). METHODS: The analytes were detected in the selected reaction monitoring mode on a triple quadrupole mass spectrometer with the positive ionization mode. Carbamazepine was utilized as the internal standard. The pretreatment of the plasma sample was completed based on protein precipitation with acetonitrile, and the analytes were separated on an Agilent Zorbax SB-C18 reversed-phase column (2.1 mm × 100 mm, 3.5 µm, Agilent, USA) using gradient elution. The mobile phase consisted of 0.1% formic acid in water (phase A) and 0.1% formic acid in acetonitrile (phase B). The flow rate was 0.3 mL/min, and the injection volume was 5 µL. The column temperature was set and maintained at 35°C. RESULTS: The calibration curves were linear over the range from 5.0 to 1000.0 ng/mL for gefitinib, crizotinib, and osimertinib; from 50.0 to 4000.0 ng/mL for icotinib and erlotinib; and from 5.0 to 400.0 ng/mL for afatinib. Linear correlation coefficients were >0.990 for all regression curves. The intra- and interday accuracy and precision of the method were within ±15.0% and not more than 15.0%, respectively. The mean recovery of all the analytes ranged from 70.18% to 110.76%, the matrix effect was from 88.85% to 127.58%, and stability was within ±15.0%. CONCLUSION: This newly developed method was sensitive, simple, and robust and could be used in therapeutic drug monitoring of six tyrosine kinase inhibitors in NSCLC patients.

6.
Viruses ; 12(3)2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-32120864

RESUMO

The Rift Valley fever virus (RVFV) is an arthropod-borne virus that can not only cause severe disease in domestic animals but also in humans. However, the licensed vaccines or available therapeutics for humans do not exist. Here, we report two Gn-specific neutralizing antibodies (NAbs), isolated from a rhesus monkey immunized with recombinant human adenoviruses type 4 expressing Rift Valley fever virus Gn and Gc protein (rHAdV4-GnGcopt). The two NAbs were both able to protect host cells from RVFV infection. The interactions between NAbs and Gn were then characterized to demonstrate that these two NAbs might preclude RVFV glycoprotein rearrangement, hindering the exposure of fusion loops in Gc to endosomal membranes after the virus invades the host cell. The target region for the two NAbs is located in the Gn domain III, implying that Gn is a desired target for developing vaccines and neutralizing antibodies against RVFV.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Febre do Vale de Rift/imunologia , Vírus da Febre do Vale do Rift/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Epitopos , Humanos , Imunização , Macaca mulatta , Modelos Moleculares , Conformação Molecular , Testes de Neutralização , Ligação Proteica , Febre do Vale de Rift/virologia , Relação Estrutura-Atividade , Proteínas do Envelope Viral/química
7.
Mol Med Rep ; 18(1): 391-398, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29749520

RESUMO

Upregulated gene 11 (URG11) represents a gene upregulated by hepatitis B virus X protein and is involved in the biological processes of multifarious tumors. The present study aimed to investigate the protective effects and regulatory mechanisms of URG11 in benign prostatic hyperplasia (BPH). URG11, Ras homolog family member A (RhoA) and Rho­associated protein kinase 1 (ROCK1) expression was detected in patients with BPH using reverse transcription­quantitative polymerase chain reaction (RT­qPCR). Furthermore, URG11 expression was silenced using URG11­targeting small interfering RNAs. In addition, cell viability was determined by performing a Cell Counting Kit­8 assay, and the effect of URG11 on the cell cycle was investigated by flow cytometry. Expression levels of cyclin D1, p27, E­cadherin, N­cadherin, vimentin, RhoA and ROCK1 were investigated by RT­qPCR and western blotting. The results revealed that the expression levels of URG11, RhoA and ROCK1 were enhanced in patients with BPH­1 cells compared with matched healthy controls. Furthermore, it was demonstrated that transforming growth factor­ß (TGF­ß) induced the proliferation of BPH­1 cells in vitro, and silencing of URG11 inhibited the effects of TGF­ß on BPH­1 cell proliferation and the cell cycle. In addition, silencing of URG11 altered the expression levels of cell cycle­associated genes, epithelial­mesenchymal transition­associated genes, and RhoA and ROCK1 protein levels. Thus, the results of the present study suggest that URG11 may be a potential therapeutic target, which may be important to inhibit the development and progression of prostatic hyperplasia.


Assuntos
Proliferação de Células , Transição Epitelial-Mesenquimal , Inativação Gênica , Hiperplasia Prostática/metabolismo , Transdução de Sinais , Transativadores/biossíntese , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Adulto , Idoso , Linhagem Celular , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Quinases Associadas a rho/genética , Proteína rhoA de Ligação ao GTP/genética
8.
Biomarkers ; 23(5): 435-445, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29465000

RESUMO

CONTEXT: Prostate cancer (PCa) is one of the most commonly diagnosed malignancy in men in the western world. OBJECTIVE: We aim to investigate the biological role of long non-coding RNA FENDRR and its mechanism in PCa. MATERIALS AND METHODS: We determined the expression of FENDRR and miR-18a-5p in PCa tissues and examined the regulatory mechanism in PCa cell lines. RESULTS: FENDRR transcripts in human PCa tissues were significantly decreased compared with the normal controls. Reduced expression of FENDRR was correlated with the increase of pathological degree and poor prognosis in PCa patients. Upregulation of FENDRR inhibited cell proliferation, increased apoptosis and decreased invasion and migration ability, which was inhibited by miR-18a-5p mimic. Knockdown of FENDRR resulted in a significant increase of PCa cell proliferation and decrease of apoptosis and this effect was inhibited miR-18a-5p inhibitor. FENDRR and RUNX1 contain potential target sites for miR-18a-5p. miR-18a-5p mimic inhibited RUNX1 expression and luciferase activity. FENDRR could increase RUNX1 expression, which was inhibited by miR-18a-5p. The effect of FENDRR on cell proliferation, apoptosis and invasion and migration ability was suppressed by silence of RUNX1. DISCUSSION AND CONCLUSION: These results position FENDRR/miR-18a-5p/RUNX1 as a potential therapeutic target and biomarker for PCa.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , RNA Longo não Codificante/farmacologia , Apoptose/efeitos dos fármacos , Ligação Competitiva/fisiologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Masculino
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