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BACKGROUND AND AIM OF THE STUDY: Many studies support that the no-touch (NT) procedure can improve the patency rate of vein grafts. However, it is not clear that the sequential vein graft early expansion in the NT technique during off-pump coronary artery bypass grafting (CABG). This study will explore this issue. METHODS: This was a prospective single-center randomized controlled clinical trial. A total of 100 patients undergoing off-pump CABG with the sequential saphenous graft were randomly assigned to two groups: the NT and conventional (CON) groups. Perioperative and postoperative data were collected during the hospital stay. The mean diameter of sequential grafts was measured using cardiac computed tomography angiography 3 months after the operation. RESULTS: There was a significant difference in the average diameter of sequential grafts between the two groups (NT: [2.98 ± 0.42], CON: [3.26 ± 0.51], p = .005). There was no difference in occlusion of sequential venous grafts between the two groups (NT: 4/48 [8.3%], CON: 5/49 [10.2%], p = 1.000). There were differences in surgery time between the two groups (NT: 220 [188,240], CON: 190 [175,230], p = .009). CONCLUSIONS: The sequential graft early expansion in the NT technique is not as pronounced as that in the conventional technique, which may have a long-term protective effect on the grafts.
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Ponte de Artéria Coronária sem Circulação Extracorpórea , Veia Safena , Angiografia Coronária , Ponte de Artéria Coronária , Humanos , Estudos Prospectivos , Veia Safena/diagnóstico por imagem , Resultado do Tratamento , Grau de Desobstrução VascularRESUMO
Objectives: To compare the long-term outcomes of coronary artery bypass grafting (CABG) vs. percutaneous coronary intervention (PCI) with drug-eluting stents (DESs) for coronary artery disease (CAD) patients with chronic kidney disease (CKD). Methods: Coronary artery disease patients with decreased kidney function (estimated glomerular filtration rate <60 ml/min/1.73 m2) who underwent CABG (n = 533) or PCI with DES (n = 952) from 2013 to 2020 were enrolled at a single center. The baseline characteristics and clinical outcomes were compared between the CABG and PCI groups for each matched pair of patients with CKD. The primary endpoint was the occurrence of all-cause death. The secondary endpoints were major adverse cardiovascular events (MACCEs) such as death, myocardial infarction (MI), stroke, and repeat revascularization. Results: A total of 1,485 patients underwent revascularization, such as 533 CABG and 952 patients with PCI. The median follow-up duration was 55.6 months (interquartile range 34.3-74.7 months). Multivariable Cox regression models were used for risk adjustment, and after propensity score matching (PSM), 399 patients were well matched in each group. The in-hospital mortality rate in the CABG group was higher than that in the PCI group, but the difference was not statistically significant (5.0 vs. 2.5%, p = 0.063). At the 1-year follow-up, CABG was associated with a lower survival rate than PCI (94.2 vs. 98.0%, hazard ratio [HR] of 3.72, 95% CI = 1.63-8.49, p < 0.01). At the end of the 5-year follow-up, the freedom from MI and the freedom from repeated revascularization were both better in the CABG group compared to the PCI group (89.1 vs. 81.7%, HR of 0.59, 95% CI = 0.38-0.92, p = 0.019; 86.9 vs. 73.8%, HR of 0.54, 95% CI = 0.36-0.81, p = 0.003, respectively). Furthermore, the freedom from MACCEs was also better in the patients of CABG compared with the patients of PCI (58.5 vs. 51.3%, HR of 0.71, 95% CI = 0.55-0.91, p = 0.030). CABG had a higher cumulative survival rate (68.4 vs. 66.0%) but without a statistically significant difference (HR of 0.92, 95% CI = 0.67-1.27, p = 0.602) compared with that of PCI. Conclusions: Compared to the use of PCI with a drug-eluting stent among patients with CKD, the use of CABG was associated with a lower MI rate, repeat revascularization rate, and lower number of MACCEs during the long-term follow-up. At a follow-up of 1 year, the number of MACCEs and other adverse events were comparable between the two cohorts, but CABG showed a lower survival rate than PCI.
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Objectives: Aims to compare the contemporary and long-term outcomes of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in coronary artery disease (CAD) patients with advanced chronic kidney disease (CKD). Methods: 823 CAD patients with advanced CKD (eGFR < 30â ml/min/1.73â m2) were collected, including 247 patients who underwent CABG and 576 patients received PCI from January 2014 to February 2021. The primary endpoint was all-cause death. The secondary endpoints included major adverse cardiac and cerebrovascular events (MACCEs), myocardial infarction (MI), stroke and revascularization. Results: Multivariable Cox regression models were used and propensity score matching (PSM) was also performed. After PSM, the 30-day mortality rate in the CABG group was higher than that in the PCI group but without statistically significant (6.6% vs. 2.4%, p = 0.24). During the first year, patients referred for CABG had a hazard ratio (HR) of 1.42 [95% confidence interval (CI), 0.41-3.01] for mortality compared with PCI. At the end of the 5-year follow-up, CABG group had a HR of 0.58 (95%CI, 0.38-0.86) for repeat revascularization, a HR of 0.77 (95%CI, 0.52-1.14) for survival rate and a HR of 0.88(95%CI, 0.56-1.18) for MACCEs as compared to PCI. Conclusions: Among patients with CAD and advanced CKD who underwent CABG or PCI, the all-cause mortality and MACCEs were comparable between the two groups in 30 days, 1-year and 5 years. However, CABG was only associated with a significantly lower risk for repeat revascularization compared with PCI at 5 years follow-up.
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Novel 2'-fluoro-6'-methylene-carbocyclic adenosine (9) was synthesized and evaluated its anti-HBV activity. The titled compound demonstrated significant antiviral activity against wild-type as well as lamivudine, adefovir and double lamivudine/entecavir resistant mutants. Molecular modeling study indicate that the 2'-fluoro moiety by a hydrogen bond, as well as the van der Waals interaction of the carbocyclic ring with the phenylalanine moiety of the polymerase promote the positive binding, even in the drug resistant mutants.
Assuntos
Adenosina/análogos & derivados , Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Mutação , Adenosina/química , Adenosina/farmacologia , Antivirais/química , Vírus da Hepatite B/genética , Testes de Sensibilidade Microbiana , Modelos MolecularesRESUMO
BACKGROUND: In the mid-1990s, the Swedish expert team proposed saphenous vein graft (SVG) harvesting with pedicle tissue. The short-term and long-term patency rates of the great saphenous vein obtained by the no-touch (NT) were higher than those obtained by the conventional (CON). In the past, NT harvesting was mainly used in on-pump coronary artery bypass grafting (CABG), and vein grafts were mostly single vein grafts. In this study, we retrospectively analyzed the safety and effectiveness of sequential vein grafts using NT harvesting in off-pump CABG. METHODS: From 2017 to 2019, a total of 505 patients were included in the study. There were 150 patients in the NT group and 355 patients in the CON group. After applying propensity score matching (1:1 matching), 148 patients were included in each group. Baseline data, graft patency, post-operative complications, leg wound complications and 1-year major adverse cardiac and cerebrovascular events (MACCEs) were compared between the two groups. RESULTS: There was no significant difference in the patency rate of sequential venous grafts between the two groups 1 year after the operation either before [NT: 7.1% (10/141) vs. CON: 11.5% (38/331), p = 0.149) or after matching (NT: 7.1% (10/140) vs. CON: 7.3% (9/124), p = 0.971]. There was no significant difference in the composite clinical endpoint between the two groups either before [NT: 3 (2.3%) vs. CON: 9 (2.8%), p = 1.000] or after matching [NT: 3 (2.3%) vs. CON: 3 (2.5%), p = 1.000]. There were differences in leg wound complications between the two groups both before [NT: 9 (6.9%) vs. CON: 6 (1.9%), p = 0.007] and after matching [NT: 9 (6.9%) vs. CON: 2 (1.7%), p = 0.043]. CONCLUSIONS: The application of the NT harvesting in off-pump CABG with sequential vein grafts is safe and effective. NT method has disadvantages in leg wound.
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BACKGROUND: Acute kidney injury (AKI) after coronary artery bypass graft (CABG) surgery is associated with significant morbidity and mortality. This retrospective study aimed to establish a risk score for postoperative AKI in a Chinese population. METHODS: A total of 1138 patients undergoing CABG were collected from September 2018 to May 2020 and divided into a derivation and validation cohort. AKI was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Multivariable logistic regression analysis was used to determine the independent predictors of AKI, and the predictive ability of the model was determined using a receiver operating characteristic (ROC) curve. RESULTS: The incidence of cardiac surgery-associated acute kidney injury (CSA-AKI) was 24.17%, and 0.53% of AKI patients required dialysis (AKI-D). Among the derivation cohort, multivariable logistic regression showed that age ≥ 70 years, body mass index (BMI) ≥ 25 kg/m2, estimated glomerular filtration rate (eGFR) ≤ 60 mL/min per 1.73 m2, ejection fraction (EF) ≤ 45%, use of statins, red blood cell transfusion, use of adrenaline, intra-aortic balloon pump (IABP) implantation, postoperative low cardiac output syndrome (LCOS) and reoperation for bleeding were independent predictors. The predictive model was scored from 0 to 32 points with three risk categories. The AKI frequencies were as follows: 0-8 points (15.9%), 9-17points (36.5%) and ≥ 18 points (90.4%). The area under of the ROC curve was 0.730 (95% CI: 0.691-0.768) in the derivation cohort. The predictive index had good discrimination in the validation cohort, with an area under the curve of 0.735 (95% CI: 0.655-0.815). The model was well calibrated according to the Hosmer-Lemeshow test (P = 0.372). CONCLUSION: The performance of the prediction model was valid and accurate in predicting KDIGO-AKI after CABG surgery in Chinese patients, and could improve the early prognosis and clinical interventions.
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SCY-635 is a novel nonimmunosuppressive cyclosporine-based analog that exhibits potent suppression of hepatitis C virus (HCV) replication in vitro. SCY-635 inhibited the peptidyl prolyl isomerase activity of cyclophilin A at nanomolar concentrations but showed no detectable inhibition of calcineurin phosphatase activity at concentrations up to 2 microM. Metabolic studies indicated that SCY-635 did not induce the major cytochrome P450 enzymes 1A2, 2B6, and 3A4. SCY-635 was a weak inhibitor and a poor substrate for P-glycoprotein. Functional assays with stimulated Jurkat cells and stimulated human peripheral blood mononuclear cells indicated that SCY-635 is a weaker inhibitor of interleukin-2 secretion than cyclosporine. A series of two-drug combination studies was performed in vitro. SCY-635 exhibited synergistic antiviral activity with alpha interferon 2b and additive antiviral activity with ribavirin. SCY-635 was shown to be orally bioavailable in multiple animal species and produced blood and liver concentrations of parent drug that exceeded the 50% effective dose determined in the bicistronic con1b-derived replicon assay. These results suggest that SCY-635 warrants further investigation as a novel therapeutic agent for the treatment of individuals who are chronically infected with HCV.
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Antivirais/farmacologia , Ciclosporinas/química , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Imunossupressores/química , RNA Viral/genética , Animais , Antivirais/química , Antivirais/farmacocinética , Antivirais/uso terapêutico , Linhagem Celular , Células Cultivadas , Ciclofilina A/metabolismo , Ciclosporinas/farmacocinética , Ciclosporinas/farmacologia , Ciclosporinas/uso terapêutico , Cães , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Haplorrinos , Hepatite C/tratamento farmacológico , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Interleucina-2/metabolismo , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Camundongos , Estrutura Molecular , Ratos , Replicação Viral/efeitos dos fármacosRESUMO
An efficient synthesis of [D-lysine](8)cyclosporin A has been developed. Several analogs of [D-lysine](8)cyclosporin A have been synthesized and show promising anti-HCV activity, particularly compounds 39 and 43, which each exhibit an anti-HCV EC(50)<200 nM, and are each ≥50-fold less immunosuppressive than cyclosporin A.
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Antivirais/síntese química , Antivirais/farmacologia , Ciclosporina/síntese química , Ciclosporina/farmacologia , Hepacivirus/efeitos dos fármacos , Cristalografia por Raios X , Modelos MolecularesRESUMO
BACKGROUND: Numerous studies have highlighted that long noncoding RNA (lncRNA) can indirectly regulate the expression of mRNAs by binding to microRNA (miRNA). LncRNA-associated ceRNA networks play a vital role in the initiation and progression of several pathological mechanisms. However, the lncRNA-miRNA-mRNA ceRNA network in endothelial cells under cyclic stretch is seldom studied. METHODS: The miRNA, mRNA, and lncRNA expression profiles of 6 human umbilical vein endothelial cells (HUVECs) under circumferential stress were obtained by next-generation sequencing (NGS). We identified the differential expression of miRNAs, mRNAs, and lncRNAs using the R software package GDCRNATools. Cytoscape was adopted to construct a lncRNA-miRNA-mRNA ceRNA network. In addition, through GO and KEGG pathway annotations, we analyzed gene functions and their related pathways. We also adopted ELISA and TUNEL to investigate the effect of si-NEAT1 on endothelial inflammation and apoptosis. RESULTS: We recognized a total of 32978 lncRNAs, 1046 miRNAs, and 31958 mRNAs in 6 samples; among them, 155 different expressed lncRNAs, 74 different expressed miRNAs, and 960 different mRNAs were adopted. Based on the established theory, the ceRNA network was composed of 13 lncRNAs, 44 miRNAs, and 115 mRNAs. We constructed and visualized a lncRNA-miRNA-mRNA network, and the top 20 nodes are identified after calculating their degrees. The nodes with most degrees in three kinds of RNAs are hsa-miR-4739, NEAT1, and MAP3K2. Functional analysis showed that different biological processes enriched in biological regulation, response to stimulus and cell communication. Pathway analysis was mainly enriched in longevity regulating, cell cycle, mTOR, and FoxO signaling pathway. Circumferential stress can significantly downregulate NEAT1, and after transducing si-NEAT1 for 24 h, inflammatory cytokine IL-6 and MCP-1 were significantly increased; furthermore, fewer TUNEL-positive cells were found in the si-NEAT1 treated group. CONCLUSIONS: The establishing of a ceRNA network can help further understand the mechanism of vein graft failure. Our data demonstrated that NEAT1 may be a core factor among the mechanical stress factors and that cyclic stress can significantly reduce expression of NEAT1, give rise to inflammation in the early stage of endothelial dysfunction, and promote EC apoptosis, which may play an essential role in vein graft failure.
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The fully glycosylated human omega interferon produced from CHO-SS cells (glycosylated IFN-omega) has been shown to be well-tolerated in man and to induce a sustained virologic response in patients infected with hepatitis C virus (HCV). We examined the antiviral activity of glycosylated IFN-omega and various human IFNs (IFN-alpha, -beta, -gamma and non-glycosylated bacterial (Escherichia coli) recombinant IFN-omega (non-glycosylated IFN-omega)) against HCV RNA replicons and several viruses related to HCV. Since none of the IFNs displayed cytotoxicity we compared their activities based on the effective concentration of the IFN that inhibited virus growth by 50% (EC50). Glycosylated IFN-omega was found to be the most potent antiviral agent of all the IFNs tested against bovine viral diarrhea virus (BVDV), yellow fever virus and West Nile virus. With HCV RNA replicons, non-glycosylated IFN-omega was comparable in activity to IFN-alpha while glycosylated IFN-omega was markedly more potent, indicating that glycosylation has an important effect on its activity. Drug combination analysis of glycosylated IFN-omega+ribavirin (RBV) in BVDV showed a synergy of antiviral effects similar to IFN-alpha+RBV, as well as a unique antagonism of RBV cytotoxic effects by glycosylated IFN-omega. Transcription factor (TF) profiling indicated that IFN-alpha or glycosylated IFN-omega treatment upregulated the same 17 TFs. IFN-alpha and glycosylated IFN-omega also upregulated 9 and 40 additional unique TFs, respectively. The differences in the expression of these TFs were modest, but statistically significantly different for eight of the TFs that were upregulated exclusively by glycosylated IFN-omega. The activation of these additional TFs by glycosylated IFN-omega might contribute to its high potency.
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Antivirais/farmacologia , Hepacivirus/genética , Interferon Tipo I/farmacologia , Interferons/farmacologia , Replicon/efeitos dos fármacos , Animais , Antivirais/imunologia , Células CHO , Bovinos , Chlorocebus aethiops , Cricetinae , Cricetulus , Combinação de Medicamentos , Humanos , Interferon Tipo I/imunologia , Interferons/imunologia , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Replicon/genética , Fatores de Transcrição/genética , Células VeroRESUMO
The global prevalence of hepatitis C virus (HCV) infection and serious health consequences associated with chronic state of the disease have become a significant health problem worldwide. Currently, there is no vaccine to prevent the disease and no specific antiviral drug directed against HCV infection. The current standard of care, interferon-based therapies, both alone or in combination with ribavirin, has demonstrated limited success and is associated with undesirable side effects. Thus, the treatment of the chronic HCV infection represents an unmet medical need. With advances in the understanding of HCV replication and the crystal structures of the virally encoded enzymes, the HCV NS3/4A serine protease and the NS5B RNA-dependent RNA polymerase have emerged as ideal targets toward the control of the disease and the development of new anti-HCV agents. In this review, we will summarize the current treatment options, and outline the approaches toward discovery of small molecule antivirals against the virally encoded enzymes. The current clinical studies of promising lead compounds are also reviewed.
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Antivirais/uso terapêutico , Desenho de Fármacos , Inibidores Enzimáticos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Inibidores de Serina Proteinase/uso terapêutico , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/química , Antivirais/farmacologia , Proteínas de Transporte/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Hepacivirus/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Inibidores de Serina Proteinase/farmacologia , Proteínas Virais/antagonistas & inibidoresRESUMO
We report here the nucleotide and deduced amino acid (aa) sequences of the small hydrophobic (SH) gene of the avian pneumovirus strain Colorado (APV/CO). The SH gene of APV/CO is 628 nucleotides in length from gene-start to gene-end. The longest ORF of the SH gene encoded a protein of 177 aas in length. Comparison of the deduced aa sequence of the SH protein of APV/CO with the corresponding published sequences of other members of genera metapneumovirus showed 28% identity with the newly discovered human metapneumovirus (hMPV), but no discernable identity with the APV subgroup A or B. Collectively, this data supports the hypothesis that: (i) APV/CO is distinct from European APV subgroups and belongs to the novel subgroup APV/C (APV/US); (ii) APV/CO is more closely related to hMPV, a mammalian metapneumovirus, than to either APV subgroup A or B. The SH gene of APV/CO was cloned using a genomic walk strategy which initiated cDNA synthesis from genomic RNA that traversed the genes in the order 3'-M-F-M2-SH-G-5', thus confirming that gene-order of APV/CO conforms in the genus Metapneumovirus. We also provide the sequences of transcription-signals and the M-F, F-M2, M2-SH and SH-G intergenic regions of APV/CO.
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Metapneumovirus/classificação , Metapneumovirus/genética , Pneumovirus/classificação , Pneumovirus/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Aves/virologia , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Estados Unidos , Proteínas Virais/químicaRESUMO
BACKGROUND: Human HBV and HIV integrate their retro-transcribed DNA proviruses into the human host genome. Existing antiretroviral drug regimens fail to directly target these intrachromosomal xenogenomes, leading to persistence of viral genetic information. Retinazone (RTZ) constitutes a novel vitamin A-derived (retinoid) thiosemicarbazone derivative with broad-spectrum antiviral activity versus HIV, HCV, varicella-zoster virus and cytomegalovirus. METHODS: The in vitro inhibitory action of RTZ on HIV-1 strain LAI, human HBV strain ayw, HCV-1b strain Con1, enhanced green fluorescent protein-expressing Ebola virus Zaire 1976 strain Mayinga, wild-type Ebola virus Zaire 1976 strain Mayinga, human herpesvirus 6B and Kaposi's sarcoma-associated herpesvirus replication was investigated. The binding of RTZ to human glucocorticoid receptor was determined. RESULTS: RTZ inhibits blood-borne human HBV multiplication in vitro by covalent inactivation of intragenic and intraexonic viral glucocorticoid response elements, and, in close analogy, RTZ suppresses HIV-1 multiplication in vitro. RTZ disrupts the multiplication of blood-borne human HCV and Ebola Zaire virus at nanomolar concentrations in vitro. RTZ has the capacity to bind to human glucocorticoid receptor, to selectively and covalently bind to intraexonic viral glucocorticoid response elements, and thereby to inactivate human genome-integrated proviral DNA of human HBV and HIV. CONCLUSIONS: RTZ represents the first reported antiviral agent capable of eradicating HIV and HBV proviruses from their human host. Furthermore, RTZ represents a potent and efficacious small-molecule in vitro inhibitor of Ebola virus Zaire 1976 strain Mayinga replication.
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Antivirais/farmacologia , Ebolavirus/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Hepacivirus/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Tiossemicarbazonas/farmacologia , Vitamina A/análogos & derivados , Antivirais/química , Ebolavirus/classificação , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Tiossemicarbazonas/química , Vitamina A/química , Vitamina A/farmacologiaRESUMO
PURPOSE: Although chronic hepatitis C virus (HCV) infection has been treated with the combination of interferon alpha (IFN-α) and ribavirin (RBV) for over a decade, the mechanism of antiviral synergy is not well understood. We aimed to determine the synergistic antiviral mechanisms of IFN-α and RBV combination treatment using HCV cell culture. METHODS: The antiviral efficacy of IFN-α, RBV alone and in combination was quantitatively measured using HCV infected and replicon cell culture. Direct antiviral activity of these two drugs at the level of HCV internal ribosome entry site (IRES) mediated translation in Huh-7 cell culture was investigated. The synergistic antiviral effect of IFN-α and RBV combination treatment was verified using both the CalcuSyn Software and MacSynergy Software. RESULTS: RBV combination with IFN-α efficiently inhibits HCV replication cell culture. Our results demonstrate that IFN-α, interferon lambda (IFN-λ) and RBV each inhibit the expression of HCV IRES-GFP and that they have a minimal effect on the expression of GFP in which the translation is not IRES dependent. The combination treatments of RBV along with IFN-α or IFN-λ were highly synergistic with combination indexes <1. We show that IFN-α treatment induce levels of PKR and eIF2α phosphorylation that prevented ribosome loading of the HCV IRES-GFP mRNA. Silencing of PKR expression in Huh-7 cells prevented the inhibitory effect of IFN-α on HCV IRES-GFP expression. RBV also blocked polyribosome loading of HCV-IRES mRNA through the inhibition of cellular IMPDH activity, and induced PKR and eIF2α phosphorylation. Knockdown of PKR or IMPDH prevented RBV induced HCV IRES-GFP translation. CONCLUSIONS: We demonstrated both IFN-α and RBV inhibit HCV IRES through prevention of polyribosome formation. The combination of IFN-α and RBV treatment synergistically inhibits HCV IRES translation via using two different mechanisms involving PKR activation and depletion of intracellular guanosine pool through inhibition of IMPDH.
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Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Interferons/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/genética , RNA Viral/genética , Ribavirina/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Sinergismo Farmacológico , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Genoma Viral , Humanos , IMP Desidrogenase/metabolismo , Polirribossomos/metabolismo , Ligação Proteica/efeitos dos fármacos , Biossíntese de Proteínas/fisiologia , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Replicon , Replicação Viral/efeitos dos fármacos , eIF-2 Quinase/metabolismoRESUMO
Hepatitis C virus (HCV) infection is a serious problem worldwide, but no effective drugs are currently available. Through screening of our privileged structure library, quinoxalin-2(1H)-one derivative N-(7-(cyclohexyl(methyl)amino)-3-oxo-3,4-dihydroquinoxalin-6-ylcarbamothioyl)benzamide (compound 1) was identified as potent HCV inhibitor in vitro. Subsequently, a structure-activity relationship analysis was carried out that showed N-(7-(cyclohexyl(methyl)amino)-3-oxo-3,4-dihydroquinoxalin-6-ylcarbamothioyl)furan-2-carboxamide (compound 11, EC(50)=1.8 µM, SI=9.6), 6-(cyclohexyl(methyl)amino)-7-(4-phenylthiazol-2-ylamino)quinoxalin-2(1H)-one (compound 33, EC(50)=1.67 µM, SI=37.4), 2-(cyclohexyl(methyl)amino)-3-(4-phenylthiazol-2-ylamino)-7,8,9,10-tetrahydro-5H-pyrido[1,2-a]quinoxalin-6(6aH)-one (compound 60, EC(50)=1.19 µM, SI=9.27), 8-(cyclohexyl(methyl)amino)-7-(4-phenylthiazol-2-ylamino)pyrrolo[1,2-a]quinoxalin-4(5H)-one (compound 65, EC(50)=1.82 µM, SI=9.9), and 6-(diethylamino)-7-(4-phenylthiazol-2-ylamino)quinoxalin-2(1H)-one (compound 78, EC(50)=1.27 µM, SI=17.9) acted against HCV. The data from the structure-activity relationship study suggests that quinoxalin-2(1H)-one derivatives exhibited potent activity against HCV.
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Hepacivirus/efeitos dos fármacos , Quinoxalinas/química , Quinoxalinas/farmacologia , Replicação Viral/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Modelos Químicos , Modelos Moleculares , Estrutura Molecular , Quinoxalinas/síntese química , Relação Estrutura-AtividadeRESUMO
The novel small molecule, BIT225 (N-[5-(1-methyl-1H-pyrazol-4-yl)-napthalene-2-carbonyl]-guanidine: CAS No. 917909-71-8), was initially identified using a screening strategy designed to detect inhibitors of Hepatitis C virus (HCV) p7 ion channel activity. Here we report that BIT225 has potent stand-alone antiviral activity against the HCV model pestivirus bovine viral diarrhea virus (BVDV) with an IC(50) of 314nM. Combinations of BIT225 with recombinant interferon alpha-2b (rIFNalpha-2b) show synergistic antiviral action against BVDV and the synergy is further enhanced by addition of ribavirin. Synergy was also observed between BIT225 and two nucleoside analogues known to inhibit the HCV RNA-dependent RNA polymerase. BIT225 has successfully completed a phase Ia dose escalating, single dose safety trial in healthy volunteers and a phase Ib/IIa trial to evaluate the safety and pharmacokinetics of repeated dosing for selected doses of BIT225 in HCV-infected persons. A modest, but statistically significant drop in patient viral load was detected over the 7 days of dosing (ref. www.biotron.com.au). Given the critical role of the p7 protein in the HCV life cycle and pathogenicity, our data indicate that molecules like BIT225, representing a new class of antiviral compounds, may be developable for therapeutic use against HCV infection, either as monotherapy, or in combination with other HCV drugs.
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Antivirais/farmacologia , Vírus da Diarreia Viral Bovina/efeitos dos fármacos , Interferon-alfa/farmacologia , Ribavirina/farmacologia , Proteínas Virais/antagonistas & inibidores , Animais , Bovinos , Linhagem Celular , Ensaios Clínicos como Assunto , Sinergismo Farmacológico , Humanos , Concentração Inibidora 50 , Interferon alfa-2 , Estrutura Molecular , Proteínas RecombinantesRESUMO
A series of 7-deazaneplanocin A (7-DNPA, 2) analogues were synthesized and evaluated for in vitro antiviral activity against HBV and HCV. The syntheses of target carbocyclic nucleosides were accomplished via a convergent procedure. 7-Substitutions were introduced by using 7-substituted-7-deaza heterocyclic base precursors (F, Cl, Br, and I) or via substitution reactions after the synthesis of the carbocyclic nucleosides. Among the synthesized compounds, 2, 13-15, 24, and 27 exhibited significant anti-HCV activity (EC(50) ranged from 1.8 to 20.1 microM) and compounds 2, 15, 22, and 24 demonstrated moderate to potent anti-HBV activity (EC(50) = 0.3-3.3 microM). In addition, compound 24 also showed activity against lamivudine- and adefovir-associated HBV mutants.
Assuntos
Adenosina/análogos & derivados , Antivirais/síntese química , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Vírus da Hepatite B/efeitos dos fármacos , Adenosina/síntese química , Adenosina/química , Adenosina/farmacologia , Antivirais/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Hepacivirus/fisiologia , Vírus da Hepatite B/genética , Humanos , Estrutura Molecular , Mutação/genética , Replicação Viral/efeitos dos fármacosRESUMO
The treatment of viral diseases remains an intractable problem facing the medical community. Conventional antivirals focus upon selective targeting of virus-encoded targets. However, the plasticity of viral nucleic acid mutation, coupled with the large number of progeny that can emerge from a single infected cells, often conspire to render conventional antivirals ineffective as resistant variants emerge. Compounding this, new viral pathogens are increasingly recognized and it is highly improbable that conventional approaches could address emerging pathogens in a timely manner. Our laboratories have adopted an orthogonal approach to combat viral disease: Target the host to deny the pathogen the ability to cause disease. The advantages of this novel approach are many-fold, including the potential to identify host pathways that are applicable to a broad-spectrum of pathogens. The acquisition of drug resistance might also be minimized since selective pressure is not directly placed upon the viral pathogen. Herein, we utilized this strategy of host-oriented therapeutics to screen small molecules for their abilities to block infection by multiple, unrelated virus types and identified FGI-104. FGI-104 demonstrates broad-spectrum inhibition of multiple blood-borne pathogens (HCV, HBV, HIV) as well as emerging biothreats (Ebola, VEE, Cowpox, PRRSV infection). We also demonstrate that FGI-104 displays an ability to prevent lethality from Ebola in vivo. Altogether, these findings reinforce the concept of host-oriented therapeutics and present a much-needed opportunity to identify antiviral drugs that are broad-spectrum and durable in their application.
RESUMO
Woodchuck hepatitis virus (WHV) is a valuable animal model system for studies of hepatitis B virus infection and accurate assessments of WHV viral load are necessary in these studies. Wild-captured woodchucks that are naturally infected with WHV are sometimes used in these studies, however, the sequence variation in WHV isolates generally precludes the use of TaqMan PCR. To facilitate this, we have created a real-time TaqMan PCR assay for WHV using degenerate primers with inosine residues employed at the locations of known sequence heterogeneity. This TaqMan assay has a dynamic range of 10-10(8) genomic equivalents (ge) of WHV DNA per reaction and the assay is robust and reproducible in the 10(2)-10(7) ge WHV DNA per reaction range (intra-assay coefficient of variation (CV) <2.1%, inter-assay CV <2.9%). During our assay validation, we cloned and analyzed a series of six naturally occurring virus variants that contained sequence heterogeneity in the TaqMan primer sequence region. We showed that the presence of some of these sequence variations prevented the PCR amplification of the target when regular primer sequences were used, while degenerate primer sequences were able to efficiently amplify all tested sequences equally well.
Assuntos
Primers do DNA/genética , DNA Viral/análise , DNA Viral/genética , Vírus da Hepatite B da Marmota/genética , Reação em Cadeia da Polimerase/métodos , Taq Polimerase/metabolismo , Animais , Sequência de Bases , Genoma Viral , Genótipo , Vírus da Hepatite B da Marmota/isolamento & purificação , Dados de Sequência Molecular , Plasmídeos/genética , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e EspecificidadeRESUMO
Paramyxoviruses such as human parainfluenza viruses that bear inserts encoding protective antigens of heterologous viruses can induce an effective immunity against the heterologous viruses in experimental animals. However, vectors based on common human pathogens would be expected to be restricted in replication in the adult human population due to high seroprevalence, an effect that would reduce vector immunogenicity. To address this issue, we evaluated Newcastle disease virus (NDV), an avian paramyxovirus that is serotypically distinct from common human pathogens, as a vaccine vector. Two strains were evaluated: the attenuated vaccine strain LaSota (NDV-LS) that replicates mostly in the chicken respiratory tract and the Beaudette C (NDV-BC) strain of intermediate virulence that produces mild systemic infection in chickens. A recombinant version of each virus was modified by the insertion, between the P and M genes, of a gene cassette encoding the human parainfluenza virus type 3 (HPIV3) hemagglutinin-neuraminidase (HN) protein, a test antigen with considerable historic data. The recombinant viruses were administered to African green monkeys (NDV-BC and NDV-LS) and rhesus monkeys (NDV-BC only) by combined intranasal and intratracheal routes at a dose of 10(6.5) PFU per site, with a second equivalent dose administered 28 days later. Little or no virus shedding was detected in nose-throat swabs or tracheal lavages following immunization with either strain. In a separate experiment, direct examination of lung tissue confirmed a highly attenuated, restricted pattern of replication by parental NDV-BC. The serum antibody response to the foreign HN protein induced by the first immunization with either NDV vector was somewhat less than that observed following a wild-type HPIV3 infection; however, the titer following the second dose exceeded that observed with HPIV3 infection, even though HPIV3 replicates much more efficiently than NDV in these animals. NDV appears to be a promising vector for the development of vaccines for humans; one application would be in controlling localized outbreaks of emerging pathogens.