Search

Symptoms of COVID-19 range from asymptomatic/mild symptoms to severe illness and death, consequence of an excessive inflammatory process triggered by SARS-CoV-2 infection. The diffuse inflammation leads to endothelium dysfunction in pulmonary blood vessels, uncoupling eNOS activity, lowering NO production, causing pulmonary physiological alterations and coagulopathy. On the other hand, iNOS activity is increased, which may be advantageous for host defense, once NO plays antiviral effects. However, overproduction of NO may be deleterious, generating a pro-inflammatory effect. In this review, we discussed the role of endogenous NO as a protective or deleterious agent of the respiratory and vascular systems, the most affected in COVID-19 patients, focusing on eNOS and iNOS roles. We also reviewed the currently available NO therapies and pointed out possible alternative treatments targeting NO metabolism, which could help mitigate health crises in the present and future CoV’s spillovers., Graphical abstract Image 1

COVID-19 has resulted in more than 490 million people being infected worldwide, with over 6 million deaths by April 05th, 2022. Even though the development of safe vaccine options is an important step to reduce viral transmission and disease progression, COVID-19 cases will continue to occur, and for those cases, efficient treatment remains to be developed. Here, a drug repurposing strategy using nanotechnology is explored to develop a therapy for COVID-19 treatment. Nanoparticles (NPs) based on PLGA for fingolimod (FTY720) encapsulation show a size of ∼150 nm and high drug entrapment (∼90%). The NP (NP@FTY720) can control FTY720 release in a pH-dependent manner. Cytotoxicity assays using different cell lines show that NP@FTY720 displays less toxicity than the free drug. Flow cytometry and confocal microscopy reveal that NPs are actively internalized mostly through caveolin-mediated endocytosis and macropinocytosis pathways and co-localized with lysosomes. Finally, NP@FTY720 not only exhibits anti-SARS-CoV-2 activity at non-cytotoxic concentrations, but its biological potential for viral infection inhibition is nearly 70 times higher than that of free drug treatment. Based on these findings, the combination of drug repurposing and nanotechnology as NP@FTY720 is presented for the first time and represents a promising frontline in the fight against COVID-19.

Yellow fever (YF) is an acute viral hemorrhagic disease transmitted by infected mosquitoes. Large epidemics of YF occur when the virus is introduced into heavily populated areas with high mosquito density and low vaccination coverage. The lack of a specific small molecule drug treatment against YF as well as for homologous infections, such as zika and dengue, highlights the importance of these flaviviruses as a public health concern. With the advancement in computer hardware and bioactivity data availability, new tools based on machine learning methods have been introduced into drug discovery, as a means to utilize the growing high throughput screening (HTS) data generated to reduce costs and increase the speed of drug development. The use of predictive machine learning models using previously published data from HTS campaigns or data available in public databases, can enable the selection of compounds with desirable bioactivity and absorption, distribution, metabolism, and excretion profiles. In this study, we have collated cell-based assay data for yellow fever virus from the literature and public databases. The data were used to build predictive models with several machine learning methods that could prioritize compounds for in vitro testing. Five molecules were prioritized and tested in vitro from which we have identified a new pyrazolesulfonamide derivative with EC50 3.2 μM and CC50 24 μM, which represents a new scaffold suitable for hit-to-lead optimization that can expand the available drug discovery candidates for YF.

SARS-CoV-2 non-structural protein 3 (Nsp3) contains a macrodomain that is essential for coronavirus pathogenesis and is thus an attractive target for drug development. This macrodomain is thought to counteract the host interferon (IFN) response, an important antiviral signalling cascade, via the reversal of protein ADP-ribosylation, a post-translational modification catalysed by host poly(ADP-ribose) polymerases (PARPs). However, the main cellular targets of the coronavirus macrodomain that mediate this effect are currently unknown. Here, we use a robust immunofluorescence-based assay to show that activation of the IFN response induces ADP-ribosylation of host proteins and that ectopic expression of the SARS-CoV-2 Nsp3 macrodomain reverses this modification in human cells. We further demonstrate that this assay can be used to screen for on-target and cell-active macrodomain inhibitors. This IFN-induced ADP-ribosylation is dependent on PARP9 and its binding partner DTX3L, but surprisingly the expression of the Nsp3 macrodomain or the deletion of either PARP9 or DTX3L do not impair IFN signalling or the induction of IFN-responsive genes. Our results suggest that PARP9/DTX3L-dependent ADP-ribosylation is a downstream effector of the host IFN response and that the cellular function of the SARS-CoV-2 Nsp3 macrodomain is to hydrolyse this end product of IFN signalling, rather than to suppress the IFN response itself.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico O vírus Chikungunya (CHIKV) é o agente etiológico da febre de Chikungunya, uma doença transmitida globalmente através de mosquitos do gênero Aedes sp. Até o momento, não há tratamento antiviral ou vacina aprovados contra o CHIKV, sendo mandatório o desenvolvimento de novas estratégias terapêuticas. Nesse contexto, as proteínas isoladas dos venenos de serpentes têm demonstrado atividade antiviral contra diversos vírus, incluindo arboviroses relevantes para o sistema público de saúde. A fosfolipase A2CB (PLA2CB), uma proteína isolada da peçonha de Crotalus durissus terrificus, demonstrou possuir atividades anti-inflamatórias, antiparasitárias, antibacterianas e antivirais. Neste estudo, nós investigamos os vários efeitos da PLA2CB no ciclo replicativo do CHIKV in vitro. A atividade antiviral da PLA2CB foi avaliada usando CHIKV-nanoluciferase, uma construção viral inserida de um gene repórter (-nanoluc), para infectar células de rim de hamster bebê (BHK-21) e avaliar a viabilidade celular (ensaio MTT) e as taxas de infectividade (níveis de luminescência). Os resultados demostraram que a PLA2CB possui uma potente atividade antiviral, avaliada pelo índice de seletividade de 128 (razão de citotoxicidade por atividade antiviral). Identificamos que o tratamento com PLA2CB protegeu as células contra a infecção pelo CHIKV em 84%, e reduziu significativamente a entrada do vírus nas células hospedeiras por um efeito virucida maior que 99%, ou reduzindo a adsorção e desnudamento em 98 e 95%, respectivamente. Adicionalmente, a PLA2CB apresentou um efeito moderado, porém significante, inibindo 64% das etapas pós-entrada do ciclo replicativo do CHIKV. Cálculos envolvendo ancoramento molecular foram realizados, e os resultados sugerem interações entre PLA2CB e as glicoproteínas do CHIKV, principalmente com a E1, por meio de interações hidrofóbicas. Adicionalmente, análises de espectroscopia no infravermelho indicou interações da PLA2CB com glicoproteínas do CHIKV, corroborando com os dados das análises in silico. Nossos dados demonstraram os múltiplos efeitos antivirais da PLA2CB no ciclo replicativo do CHIKV, e sugerem as interações da PLA2CB com glicoproteínas do CHIKV como um modo de ação desse composto bloqueando a entrada do vírus nas células hospedeiras. Chikungunya virus (CHIKV) is the etiologic agent of Chikungunya fever, a globally spreading mosquito-borne disease. To date, there is no approved antiviral treatment or vaccine against CHIKV, being mandatory the development of new therapeutic strategies. In this context, proteins isolated from snake venoms have demonstrated antiviral activity against several virus, including arbovirus which are relevant the public health system. The phospholipase A2CB (PLA2CB), a protein isolated from the venom of Crotalus durissus terrificus, demonstrated to possess anti-inflammatory, antiparasitic, antibacterial, and antiviral activities. In this study, we investigated the multiple effects of PLA2CB on the CHIKV replicative cycle in vitro. The antiviral activity of PLA2CB was assessed using CHIKV-nanoluciferase, a viral construct inserted of a reporter gene (-nanoluc), to infect baby hamster kidney cells (BHK-21) cells and evaluate cell viability (MTT assay) and infectivity rates (luminescence levels). The results demonstrated that PLA2CB possess a strong antiviral activity judged by the selective index of 128 (ratio of cytotoxicity to antiviral activity). We identified that the treatment with PLA2CB protected the cells against CHIKV infection in 84% and strongly impaired virus entry to the host cells by a virucidal effect of over 99%, or by reducing adsorption and uncoating in 98 and 95 %, respectively. Moreover, PLA2CB presented a modest yet significant activity inhibiting 64 % of post-entry stages of CHIKV replicative cycle. Molecular docking calculations were performed and results suggested binding interactions between PLA2CB and CHIKV glycoprotein, mainly with E1 through hydrophobic interactions. In addition, infrared spectroscopy spectral analysis indicated interactions of PLA2CB and CHIKV glycoproteins, corroborating with data from in silico analyzes. Our data demonstrated the multiple antiviral effects of PLA2CB on the CHIKV replicative cycle, and suggest the interactions of PLA2CB with CHIKV glycoproteins as a mode of action of this compound on blocking virus entry to the host cells. Dissertação (Mestrado) 2022-07-24

This work was supported by Instituto Evandro Chagas/Secretaria de Vigil?ncia em Sa?de/Minist?rio da Sa?de (IEC/SVS/MS) and Funda??o Amaz?nia Paraense de Amparo ? Pesquisa (FAPESPA) Universidade Federal do Par?. N?cleo de Medicina Tropical. Programa de P?s-Gradua??o Stricto Sensu em Patologia Tropical. Bel?m, PA, Brasil / Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia e Biologia Molecular. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro de Inova??es Tecnol?gicas. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Centro de Inova??es Tecnol?gicas. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia e Biologia Molecular. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia e Biologia Molecular. Ananindeua, PA, Brasil. Minist?rio da Sa?de. Secretaria de Vigil?ncia em Sa?de. Instituto Evandro Chagas. Laborat?rio de Virologia e Biologia Molecular. Ananindeua, PA, Brasil. Universidade Federal do Par?. N?cleo de Medicina Tropical. Programa de P?s-Gradua??o Stricto Sensu em Patologia Tropical. Bel?m, PA, Brasil. Introduction: Human cytomegalovirus is one of the causes of opportunist infections in immunocompromised patients, and is triggered by factors such as state of viral latency, weakened immune responses, and development of antiviral resistance to ganciclovir, the only drug offered by the public health system in Brazil to treat the infection. The goal of this study was to identify mutations that may be associated with antiviral resistance in immunocompromised patients. Methods: Molecular analysis was performed in 82 blood samples and subjected to genomic DNA extraction by a silica-based method. Three sequences of the HCMV UL97 gene, which encodes a phosphotransferase protein required for activation of ganciclovir, were amplified by polymerase chain reaction. Pyrosequencing methods were applied to one external 2096-bp segment DNA and two internal sequences between nucleotides 1087 to 1828 to detect mutations in this gene. Results: Approximately 10% of sequences contained mutations between nucleotides 377 and 594, in conserved regions of the UL97 gene, leading to amino acid changes. Eleven coding mutations were identified, including changes leading to amino acid substitutions, E596K and S604F, which were observed in 100% of samples and are described for the first time in Brazil. In addition, one mutation (A594V) that is associated with ganciclovir resistance was detected in a kidney transplant patient. Conclusions: Further studies to detect mutations associated with HCMV resistance to antiviral drugs are required to demonstrate the need to increase the variety and availability of drugs used to treat viral infections in the public health care system in Brazil

Made available in DSpace on 2019-10-06T16:46:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Background: The World Health Organization estimates that 1% of the world population (71 million) is infected with hepatitis C virus (HCV). In 2015, three direct-acting antivirals (DAAs), simeprevir (SMV), sofosbuvir (SOF) and daclatasvir (DCV) were included in the Brazilian protocol for the treatment of chronic hepatitis C. Despite the fact that the use of these drugs is associated with higher treatment response rates and with lower incidence of side effects, studies have shown the association between the presence of viral resistance mutations and the failure of pharmacological treatment. Aim: This way, this study aimed to evaluate the safety and effectiveness of treatment for HCV genotypes 1a and 1b infected patients with these DAAs, also analyzing the occurrence and prevalence of baseline resistance associated substitutions (RAS), observing the impact of these mutations into the treatment success. Methods: Clinical data were collected from all the 262 HCV infected patients included for comparative analysis, while serum samples collected from 144 of these individuals, before treatment, were submitted to molecular biology approaches for mutation analysis into NS3, NS5A and NS5B regions. Results: Regarding the treatment regimens, 49.6% of the patients received SOF + DCV ± ribavirin and 50.4% used SOF + SMV ± ribavirin. The sustained virological response at 12 weeks post-treatment (SVR12) rate was 92.7% (93.9% for SOF plus DCV and 91.7% for SOF plus SMV). No clinical or laboratorial factor was statistically associated with SVR. The most common adverse reactions were haematological events, nausea/vomiting, headache and asthenia. Out of 144 blood samples, 70 (48.6%) had detected RAS, 34.8% treated with SOF + DCV ± ribavirin and 61.3% SOF + SMV ± ribavirin. The resistance mutations against SMV were detected into NS3: substitutions G122S (28%), I170V (22.7%), Y56F (17.3%) and V132I (14.7%). The mutations against DCV R30Q (9.1%), P58H (6.1%) and Q62E (6.1%) were observed into NS5A, and for SOF the mutations A421V (10.6%), L159F (6.4%) and C316N (6.4%) were present inside NS5B viral protein. Four patients did not reach SVR, three of them presented viruses carrying RAS (1 treated with SOF + DCV and 2 with SOF + SMV). Some of these mutations, like R30Q (present in relapsing samples) and L159F, are well known by their influence on antiviral resistance, while others, like C316N, have a compensatory effect on viral fitness, maintaining these baseline RAS. Conclusion: The use of treatment regimens composed of SOF and DCV or SOF and SMV showed a high SVR rate, despite of a high rate of RAS, and a good tolerability profile in patients with HCV genotype 1. However, the high occurrence of baseline RAS observed in this casuistic is still a concern and studies like this show the necessity to understand how they are maintained in the population and to direct more efficiently the use of DAAs. FCFRP-USP - University of São Paulo Ribeirão Preto Faculty of Pharmaceutical Sciences–Café avenue UNESP - São Paulo State University Institute of Bioscience Language and Exact Science–IBILCE Department of Biology, Cristóvão Colombo Street, 2265 FMRP-USP–University of São Paulo Ribeirão Preto School of Medicine, Bandeirantes Avenue, 3900 UNESP - São Paulo State University Institute of Bioscience Language and Exact Science–IBILCE Department of Biology, Cristóvão Colombo Street, 2265

The Zika virus (ZIKV) is an arthropod-borne virus that belongs to the Flaviviridae family. The ZIKV infection is usually asymptomatic or is associated with mild clinical manifestations; however, increased numbers of cases of microcephaly and birth defects have been recently reported. To date, neither a vaccine nor an antiviral treatment has become available to control ZIKV replication. Among the natural compounds recognized for their medical properties, flavonoids, which can be found in fruits and vegetables, have been found to possess biological activity against a variety of viruses. Here, we demonstrate that the citrus flavanone naringenin (NAR) prevented ZIKV infection in human A549 cells in a concentration-dependent and ZIKV-lineage independent manner. NAR antiviral activity was also observed when primary human monocyte-derived dendritic cells were infected by ZIKV. NAR displayed its antiviral activity when the cells were treated after infection, suggesting that NAR acts on the viral replication or assembly of viral particles. Moreover, a molecular docking analysis suggests a potential interaction between NAR and the protease domain of the NS2B-NS3 protein of ZIKV which could explain the anti-ZIKV activity of NAR. Finally, the results support the potential of NAR as a suitable candidate molecule for developing anti-ZIKV treatments.

BackgroundTreatment of hepatitis C virus infection in post-transplantation patients is a challenge due to poor tolerance and low success rates.ObjectiveTo determine the response rate to pegylated interferon and ribavirin in post-liver transplant patients with hepatitis C recurrence.MethodsBetween 18 May 2002 and 18 December 2011, 601 patients underwent liver transplantation at our service (Hospital Universitário Walter Cantídio, University of Ceará), 176 (29.2%) of whom were hepatitis C virus positive. Forty received antiviral therapy and were included in this cohort study. Twenty-eight (70%) completed the treatment protocol, which consisted of pegylated interferon and ribavirin for 48 weeks.ResultsThe sustained virological response rate was 55% according to intention-to-treat analysis. Recipient age and exposure to antiviral drugs prior to liver transplantation were associated with sustained virological response in the multivariate analysis. Patients were followed for 57 months on the average. Survival at 1 and 5 years was 100% in responders, versus 100% and 78%, respectively, in non-responders.ConclusionSustained virological response rates were satisfactory in our series of liver transplantation patients, and decreased with increasing recipient age. Non-exposure to antiviral drugs prior to liver transplantation was positively associated with sustained virological response. The overall survival of responders and non-responders was similar. ContextoO tratamento da infecção do vírus da hepatite C pós-transplante é um desafio devido à baixa tolerância dos pacientes e às baixas taxas de resposta.ObjetivoDeterminar a taxa de resposta ao interferon peguilado e ribavirina no tratamento da recorrência da hepatite C após transplante de fígado.MétodosEntre 18 de maio de 2002 e 18 de dezembro de 2011, 601 pacientes realizaram transplante hepático no Hospital Universitário Walter Cantídio, 176 (29,2%) desses eram infectados pelo vírus da hepatite C. Quarenta pacientes receberam terapia antiviral e foram incluídos nesse estudo. Vinte e sete (70%) completaram o protocolo de tratamento, que consistia de interferon peguilado e ribavirina por 48 semanas.ResultadosA taxa de resposta virológica sustentada foi de 55% de acordo com a análise por intenção de tratar. A idade dos receptores e a exposição prévia ao transplante de antivirais foram fatores associados com a resposta virológica sustentada na análise multivariada. Pacientes foram acompanhados por 57 meses em média. A sobrevida em 1 e 5 anos foi de 100% em respondedores, enquanto que em não respondedores foi de 100% e 78% respectivamente.ConclusãoA resposta virológica sustentada foi satisfatória na série de pacientes transplantados e diminuiu com o aumento da idade. A não exposição prévia ao transplante a drogas antivirais teve impacto positivo na chance de resposta virológica sustentada. A sobrevida global foi similar em respondedores e não respondedores.

The X-ray single crystal analysis of isomeric ortho, meta, and para bromo-substituted α-methylsulfonyl-α-diethoxyphosphoryl acetophenones showed that this class of compound adopts synclinal (gauche) conformations for both [-P(O)(OEt)2] and [-S(O)2Me] groups, with respect to the carbonyl functional group. The phosphonate, sulfonyl, and carbonyl functional groups are joined through an intramolecular network of attractive interactions, as detected by molecular orbital calculations at the M06-2X/6-31G(d,p) level. These interactions are responsible for the more stable conformations in the gas phase, which also persist in the solid-state structures. The main structural distinction in the title compounds relates to the torsion angle of the aryl group (with respect to the carbonyl group), which gives rise to different interactions in the crystal packing, due to the different positions of the Br atom.

Although Zika virus (ZIKV) infection is often asymptomatic, in some cases, it can lead to birth defects in newborns or serious neurologic complications in adults. However, little is known about the interplay between immune and neural cells that could contribute to the ZIKV pathology. To understand the mechanisms at play during infection and the antiviral immune response, we focused on neural precursor cells (NPCs)-microglia interactions. Our data indicate that human microglia infected with the current circulating Brazilian ZIKV induces a similar pro-inflammatory response found in ZIKV-infected human tissues. Importantly, using our model, we show that microglia interact with ZIKV-infected NPCs and further spread the virus. Finally, we show that Sofosbuvir, an FDA-approved drug for Hepatitis C, blocked viral infection in NPCs and therefore the transmission of the virus from microglia to NPCs. Thus, our model provides a new tool for studying neuro-immune interactions and a platform to test new therapeutic drugs.

Ganciclovir (GCV; systematic name: 2-amino-9-{[(1,3-dihydroxypropan-2-yl)oxy]methyl}-6,9-dihydro-1H-purin-6-one), C9H13N5O4, an antiviral drug for treating cytomegalovirus infections, has two known polymorphs (Forms I and II), but only the structure of the metastable Form II has been reported [Kawamura & Hirayama (2009). X-ray Struct. Anal. Online, 25, 51–52]. We describe a successful preparation of GCV Form I and its crystal structure. GCV is an achiral molecule in the sense that its individual conformers, which are generally chiral objects, undergo fast interconversion in the liquid state and cannot be isolated. In the crystalline state, GCV exists as two inversion-related conformers in Form I and as a single chiral conformer in Form II. This situation is similar to that observed for glycine, also an achiral molecule, whose α-polymorph contains two inversion-related conformers, while the γ-polymorph contains a single conformer that is chiral. The hydrogen bonds are exclusively intermolecular in Form I, but both inter- and intramolecular in Form II, which accounts for the different molecular conformations in the two polymorphs.

Hepatitis B (HBV) and hepatitis C (HCV) are the most common causes of chronic liver disease. Due to shared routes of transmission, co-infection with HBV and HCV is not uncommon. Higher rates of cirrhosis and hepatocelular carcinoma have been demonstrated in HBV/HCV co-infected patients. No treatment standard has been established for HBV/HCV co-infected patients. Treatment decisions must be made based upon identification of the dominant virus, usually HCV, thus patients should receive pegylated interferon alpha with ribavirin as for HCV monoinfection. Sustained virological response rates for HCV are broadly comparable with HCV monoinfected patients. There is limited information regarding the benefit of combination with nucleos(t)ide analogues. Treatment decisions may modify the complex interaction between HBV and HCV, as flares of the untreated virus may occur, namely with reactivation of HBV. The authors report a case of HBV/HCV co-infection, without a dominant profile, in which the treatment response exceeded expectations regarding the available evidence.

A atividade de três fármacos antivirais (Aciclovir [ACV], Ganciclovir [GCV] e Foscarnet [PFA]) foi testada in vitro frente aos herpesvírus bovino tipos 1 (BoHV-1), 2 (BoHV-2) e 5 (BoHV-5). Para isso, utilizou-se o teste de reducao de placas virais em cultivo celular, testando-se diferentes concentracoes dos farmacos frente a 100 doses infectantes para 50% dos cultivos celulares (DICC50) dos respectivos virus. Pelo teste de MTT (3-(4,5-Dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide), verificou-se que concentracoes inferiores a 200ƒÊg/mL dos tres antivirais resultaram em indices de viabilidade de celulas MDBK e Hep2 superiores a 80%. Com base na concentracao citotoxica para 50% das celulas (CC50) e na concentracao dos farmacos efetiva para inibir em 50% o numero de placas virais (EC50), calculou-se o indice de seletividade (IS) dos antivirais para os tres herpesvirus. Assim, o ACV demonstrou ser moderadamente ativo frente ao BoHV-1 (EC50: 112,9ƒÊg/mL e IS: 4,5), ao BoHV-2 (EC50: 114,2 ƒÊg/mL e IS: 4,5) e BoHV-5 (EC50: 96,9ƒÊg/mL e IS: 5,3). O GCV apresentou atividade moderada frente ao BoHV-2 (EC50: 33,5ƒÊg/mL e IS: 16,6) e, em menor grau, contra o BoHV-5 (EC50: 123,2ƒÊg/mL e IS: 4,5), sendo ineficaz frente ao BoHV-1 (EC50: 335,8ƒÊg/mL e IS: 1,7). O PFA apresentou atividade antiviral mais pronunciada, sendo o unico farmaco que, na concentracao de 100ƒÊg/mL, inibiu completamente a producao de placas pelos tres virus testados. O PFA foi o mais efetivo in vitro frente ao BoHV-1 (EC50: 29,5ƒÊg/mL e IS: 42,2), ao BoHV-2 (EC50: 45,2ƒÊg/mL e IS: 27,6) e ao BoHV-5 (EC50: 7,8ƒÊg/mL e IS: 160,6). Portanto, os resultados obtidos indicam que o PFA pode se constituir em um candidato para terapia experimental de infeccoes pelos herpesvirus de bovinos in vivo. The activity of three anti-herpetic drugs (Acyclovir [ACV], Gancyclovir [GCV] and Foscarnet [PFA]) was tested against bovine herpesvirus 1 (BoHV-1), 2 (BoHV-2) and 5 (BoHV-5) in vitro using the plaque reduction assay. Different drug concentrations were tested against one hundred 50% tissue culture infectious dose (TCID50) of the respective viruses. Drug concentrations lower than 200μg/mL resulted in viability rates of more than 80% for MDBK and Hep2 cells in the MTT test (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). The selectivity index (IS) of the drugs was calculated dividing the concentration of the drug that is cytotoxic for 50% of the cells (CC50) by the concentration of the drug that was effective in reducing by 50% the number of viral plaques (EC50) for the three herpesviruses. Thus, ACV was shown to be moderately active against BoHV-1 (EC50: 112.9μg/mL; IS: 4.5), BoHV-2 (EC50: 114.2μg/mL; IS: 4.5) and BoHV-5 (EC50: 96.9μg/mL; IS: 5.3). GCV was effective against BoHV-2 (EC50: 33.5μg/mL; IS: 16.6), moderately effective against BoHV-5 (EC50: 123.2μg/mL; IS: 4.5) and poorly active against BoHV-1 (EC50: 335.8μg/mL; IS: 1.7). PFA exhibited the highest antiviral activity, being the only drug that, at concentration of 100μg/mL, completely inhibited plaque formation by all three viruses. PFA was the most effective in vitro against BoHV-1 (EC50: 29.5μg/mL; IS: 42.2), BoHV-2 (EC50: 45.2μg/mL; IS: 27.6) and BoHV-5 (EC50: 7.8μg/mL; IS: 160.6). Thus, the results indicate that PFA is a promising candidate for experimental therapeutic testing in vivo against bovine herpesviruses.

O efeito antiviral do Foscarnet (PFA) foi demonstrado anteriormente em células de cultivo infectadas com três herpesvírus bovino (BoHV). No presente estudo, investigaram-se os seus efeitos sobre a infecção e doença causadas pelo BoHV-1 e BoHV-5 em coelhos infectados experimentalmente. Coelhos inoculados com o BoHV-5 pela via intraconjuntival (IC) e tratados com o PFA (100mg/kg/dia) a partir do dia 1 pós-inoculação (pi) apresentaram uma redução nos títulos de vírus excretados entre os dias 2 e 6 pi em comparação com o grupo não-tratado; essa diferença foi significativa no dia 3 pi [F(9,108) = 2,23; P

Resumo: A transmissão da artrite encefalite caprina pelo sêmen inviabiliza o uso de reprodutores soropositivos de alto valor genético. Como o vírus da artrite encefalite caprina (CAEV), é encontrado no sêmen na forma de RNA viral (vírus livre) ou DNA pró-viral dentro das células não espermáticas, possibilita que pesquisas com plantas com potencial antiviral sejam algo promissor para viabilizar o sêmen de reprodutores caprinos de grande valor zootécnico infectados. Diante disso, com essa revisão objetivou-se elucidar o potencial de fitocompostos, com comprovada ação antiviral, que poderiam vir a ser alvo de estudo para inativar o lentivírus caprino no sêmen. Inúmeras plantas de muitas famílias botânicas já foram estudadas para validação de efeito antiviral contra diversos vírus que acometem animais e humanos. Folhas, raízes, flores, e sementes demonstraram ao longo do tempo em sua constituição fitoquímica substâncias antivirais promissoras. De acordo com o tipo de planta, não apenas algumas partes dela, mas regiões inteiras da mesma são alvos das pesquisas por fitocompostos a ser usado como alternativa no combate as doenças virais. A base dos estudos nessa vertente são os metabólitos secundários, pois nas pesquisas têm apresentado compostos bioativos antivirais de alto potencial atuando nas diferentes fases do ciclo de desenvolvimento viral. Dessa forma, a biodiversidade da flora brasileira aliada à tendência de formar fitocompostos poderiam contribuir no avanço das pesquisas, a fim de encontrar uma alternativa de base natural, potencialmente eficaz, para eliminar os riscos de transmissão do CAEV pelo sêmen. [[Prospectives of herbal remedies in the treatment of caprine semen infected by Caprine Arthritis Encephalitis virus]. Abstract: The transmission of Caprine Arthritis Encephalitis in semen limits the use of seropositive bucks that have high genetic value. The Caprine Arthritis Encephalitis virus (CAEV) may be found in the form of RNA virus (free virus) or pro-viral DNA within non-spermatic cells in semen. Thus, researches involving plants with potential antiviral activity are promising for developing techniques that allow the use of semen from high-quality production goats that are infected by this virus. Therefore, this review aimed to elucidate the potential of phytocompounds that have known antiviral activity and could be used in studies to assess inactivation of the caprine lentivirus in semen. Several plants from many botanical families have been tested for validation of antiviral effect against viruses that infect animals and humans. Leaves, roots, flowers and seeds have demonstrated promising antiviral substances in their phytochemical composition. According to the type of plant, entire regions of the specimens are used for researching phytocompounds that can serve as alternatives in the treatment of viral diseases. Most of the studies involving this subject focus on secondary metabolites and several have identified high potential compounds with bioactive antiviral activity in different stages of the viral development cycle. Hence, the biodiversity of Brazilian flora, which has a tendency for phytocompound formation, provides adequate material for research aimed at finding a natural alternative to eliminate the risk of CAEV transmission through semen. Made available in DSpace on 2019-09-27T00:41:18Z (GMT). No. of bitstreams: 1 cnpc2019Perspectivas.pdf: 231992 bytes, checksum: 140c812e42b31d726cd363880d1d4f76 (MD5) Previous issue date: 2018

Dolabellane diterpenes have considerable antiviral activity, but most studies have been focused towards compounds isolated from Dictyota brown algae. Although soft corals are also a significant source of these diterpenes, their antiviral potential has not been studied in detail. With the aim of assessing the biological activity of marine sources, we evaluated the dolabellane content in the soft corals Eunicea laciniata and E. asperula collected in Santa Marta, Colombian Caribbean. Dolabellanes 1-6 were isolated from E. laciniata while compounds 2, 4 and 5 were isolated from E. asperula. All compounds were identified by NMR, GC-EIMS, optical rotation and comparison with previously reported dolabellanes. GC-EIMS analyses showed that dolabellatrienone (2) transforms into compounds 4 and 5 as oxidation products upon prolonged storage; however, those compounds were also naturally present in the extract of the studied organisms. Pure dolabellanes were tested in vitro in antiviral assays against HSV-1. Compound 6 inhibited virus replication in infected cells (73.7% of inhibition at 50 µM) without cytotoxic effect (CC50 = 95 9), showing similar activity to the positive control Acyclovir®. Thus, compound 6 is an interesting candidate for further studies of dolabellanes as antivirals. Resumen Los dolabellanos son diterpenos con actividad antiviral, la mayor parte de los estudios se han realizado con compuestos aislados de algas pardas del genero Dictyota. Los corales blandos son también una importante fuente de dolabellanos, pero el potencial antiviral de estos ha sido muy poco estudiado. Se llevó a cabo el estudio químico de los dolabellanos presentes en los octocorales Eunicea laciniata y Eunicea asperula, recolectados en Santa Marta, Caribe colombiano. Los dolabellanos 1-6 fueron aislados del octocoral E. laciniata mientras que en E. asperula se encontraron los compuestos 2, 4 y 5. La elucidaci6n estructural se llev6 a cabo mediante RMN, espectrometría de masas, rotaci6n 6ptica y comparaci6n con reportes previos. El análisis por CG-EM evidenci6 que la dolabellatrienona (2) se puede transformar en los compuestos 4 y 5 como producto del almacenamiento prolongado, no obstante, tales compuestos también estuvieron presentes en los extractos de los organismos estudiados. El compuesto 6 inhibi6 la replicaci6n del VHS-1 (73,7% de inhibición en células infectadas a una concentraci6n de 50 µM) sin efecto citot6xico (CC50 = 959), mostrando una citotoxicidad similar al Aciclovir®, un control positivo, por lo cual es un candidato para la realizaci6n de estudios adicionales sobre el potencial antiviral de los dolabellanos. Resumo Os dolabellanos são diterpenos que têm mostrado atividade antiviral, os estudos neste campo estão centrados nos compostos isolados de algas do gênero Dictyota. Os octocorais também são uma fonte importante de dolabellanos, mas não tem sido estudados. Foirealizado o estudo químico dos octocorais Eunicea laciniata e Eunicea asperula, coletados em Santa Marta, Caribe Colombiano. O estudo químico dos dois organismos permitiu o isolamento dos dolabellanos 1-6 de E. laciniata, enquanto que para E. aspérula foram identificados os compostos 2, 4 e 5. A elucidação estrutural foi realizada mediante RMN, espectrometria de massas, rotação óptica e comparação com os dados da literatura. A análise por GC-MS evidenciou que a dolabelatrienona (2) pode gerar os compostos 4 e 5 como produto de degradação, a partir de um armazenamento prolongado. No entanto, os compostos também estavam presentes nos extratos dos organismos estudados. O composto 6 mostrou uma citotoxicidade similar ao Aciclovir®, um controle positivo, numa porcentagem de inibição da replicação do HVS-1 (73,7% de inibição em células infectadas na concentração de 50 µM) sem efeito citotóxico (CC50 = 959), o quetorna esse composto um candidato para o desenvolvimento de antivirais.

Chronic hepatitis C virus (HCV) infection exists in a large proportion of patients undergoing renal transplantation. Nowadays it is not considered to be an absolute contraindication to transplantation; however, it is associated with an increased risk for the patient and accounts for a shorter half-life of the renal allograft. We present three transplant recipients who displayed serious hepatic dysfunction after renal transplantation due to an HCV infection. In two of these cases, the liver biopsies established the diagnosis of FCH. In the third case, the liver biopsy was compatible with the early stages of FCH. All patients were started on peg-interferon alfa 2-b and ribavirin with subsequent normalization of hepatic function and early complete viral responses.

CONTEXT: Chronic hepatitis C as well as non-alcoholic fatty liver disease are recognized as the main cause of liver disease in Western countries. It is common to see the concomitance of the diseases and the influence of steatosis in the sustained virological response of patients with hepatitis C virus. OBJECTIVE: Assess the sustained virological response in chronic hepatitis C patients according to the presence of liver steatosis. METHODS: One hundred sixty patients with chronic hepatitis C were retrospectively evaluated. Demographic data such as gender, age, body mass index, presence of diabetes mellitus and systemic arterial hypertension, virus genotype and use of pegylated interferon were analyzed, as was the staging of fibrosis and the presence of steatosis at histology. RESULTS: Most patients were male (57.5%), with a mean age of 48 ± 9.7 years. The most frequent genotype observed was 3 (56.9%) and, in the histological evaluation, steatosis was observed in 65% of the patients (104/160). Sustained virological response in patients with steatosis occurred in 38.5%, and in 32.1% in patients without steatosis (P = 0.54). When we analyzed possible factors associated with the presence of steatosis, only body mass index and systemic arterial hypertension revealed a significant association. When the factors that influenced sustained virological response were evaluated in a logistic regression, genotype and use of pegylated interferon proved to be independent factors associated to the response. CONCLUSION: In the evaluated patients the presence of liver steatosis did not influence the sustained virological response of patients with chronic hepatitis C treated with interferon and ribavirin. CONTEXTO: Tanto a hepatite crônica pelo vírus C quanto a doença hepática gordurosa não-alcoólica são reconhecidas como causas frequentes de doença hepática nos países ocidentais. É comum observar a concomitância das duas doenças e a influência da esteatose na resposta virológica sustentada dos pacientes com hepatite crônica pelo vírus C. OBJETIVO: Avaliar a resposta virológica sustentada nos pacientes com hepatite crônica pelo vírus C de acordo com a presença de esteatose. MÉTODOS: Foram avaliados, retrospectivamente, 160 pacientes com hepatite crônica C. Dados demográficos, como sexo, idade, índice de massa corpórea, presença de diabetes mellitus e hipertensão arterial sistêmica, genótipo do vírus e uso de interferon peguilado foram analisados, bem como o estadiamento e a presença de esteatose, quando da histologia. RESULTADOS: A maioria dos pacientes era masculina (57,5%), com média de idade de 48 anos ± 9,7. O genótipo mais frequente foi o 3 (56,9%) e, na avaliação histológica, foi observada esteatose em 65% dos pacientes (104/160). A resposta virológica sustentada nos pacientes com esteatose foi de 38,5%, sendo de 32,1% nos pacientes sem esteatose (P = 0,54). Quando se analisaram possíveis fatores associados à presença de esteatose, somente índice de massa corpórea e hipertensão arterial sistêmica estiveram associados de forma significativa. Quando se avaliaram em regressão logística os fatores que influenciaram a resposta virológica sustentada, genótipo e uso de interferon peguilado mostraram-se fatores independentes associados à resposta. CONCLUSÃO: A presença de esteatose hepática não influenciou a resposta virológica sustentada de pacientes com hepatite crônica pelo vírus C tratados com interferon e ribavirina.

Cytomegalovirus (CMV) is the most common viral infection after transplantation. Valganciclovir (VGC) is established for prophylaxis and treatment of CMV infections, but leukopenia which appears in 10% to 13% (severe in 4.9%) is the principal side effect. We have recently noted an increased incidence of leukopenia and severe neutropenia among our renal transplant patients and thought to identify the associated factors. We conducted a retrospective analysis of all kidney transplantations performed between January 2005 and December 2006. All patients received mycophenolate mofetil (MMF), tacrolimus, and steroids. VGC was used for targeted prophylaxis and preemptive therapy of CMV infection, with doses adjusted to renal function. Of the 64 patients undergoing renal transplantation 13 (20.3%) developed leukopenia within 3 +/- 2 months after transplantation with severe neutropenia in 5 (7.8%). All patients were on MMF and VGC (VGC 605 +/- 296 mg/d). Leukopenia was significantly associated with simultaneous liver-kidney transplantation and with second kidney transplantations (P < .01). The incidence of leukopenia was higher among patients under VGC since day 1 of transplantation (P = .008) with maximal incidence observed among patients prescribed 900 mg/d as opposed to those on lower doses (P < .01). There was no increase in CMV infection among patients with a low dose of VGC. No patient developed clinical CMV disease. In conclusion, VGC prophylaxis was associated with an increased frequency of leukopenia on MMF-tacrolimus treated patients or regimens. Low-dose VGC for CMV prophylaxis appeared to be as effective as high-dose treatment, and associated less frequently with leukopenia and neutropenia.