SARS- CoV-2 infection and oxidative stress in early-onset preeclampsia

SARS-CoV-2 causes coronavirus disease 2019 (COVID-19) also in pregnant women. Infection in pregnancy leads to maternal and placental functional alterations. Pregnant women with vascular defects such as preeclampsia show high susceptibility to SARS-CoV-2 infection by undefined mechanisms. Pregnant women infected with SARS-CoV-2 show higher rates of preterm birth and caesarean delivery, and their placentas show signs of vasculopathy and inflammation. It is still unclear whether the foetus is affected by the maternal infection with this virus and whether maternal infection associates with postnatal affections. The SARS-CoV-2 infection causes oxidative stress and activation of the immune system leading to cytokine storm and next tissue damage as seen in the lung. The angiotensin-converting-enzyme 2 expression is determinant for these alterations in the lung. Since this enzyme is expressed in the human placenta, SARS-CoV-2 could infect the placenta tissue, although reported to be of low frequency compared with maternal lung tissue. Early-onset preeclampsia (eoPE) shows higher expression of ADAM17 (a disintegrin and metalloproteinase 17) causing an imbalanced renin-angiotensin system and endothelial dysfunction. A similar mechanism seems to potentially account for SARS-CoV-2 infection. This review highlights the potentially common characteristics of pregnant women with eoPE with those with COVID-19. A better understanding of the mechanisms of SARS-CoV-2 infection and its impact on the placenta function is determinant since eoPE/COVID-19 association may result in maternal metabolic alterations that might lead to a potential worsening of the foetal programming of diseases in the neonate, young, and adult

Unusual presentation of hepatitis B serological markers in an Amerindian community of Venezuela with a majority of occult cases

<p>Abstract</p> <p>Background</p> <p>Occult hepatitis B infection (OBI) is characterized by the presence of hepatitis B virus (HBV) DNA in the absence of HBsAg in the serum of patients. The aim of this study was to characterize HBV infection among a Piaroa community, an Amerindian group which exhibits significant evidence of exposure to HBV but relatively low presence of HBsAg, and to explore the presence of OBI in this population.</p> <p>Results</p> <p>Of 150 sera, with 17% anti-HBc and 1.3% HBsAg prevalence, 70 were tested for the presence of HBV DNA. From these, 25 (36%) were found positive for HBV DNA by PCR in the core region. Two of these 25 sera were HBsAg positive, indicating an overt infection. Of the remaining 68 sera tested, 23 exhibited OBI. Of these, 13 were HBV DNA out of 25 anti-HBc positive (52%) and 10 HBV DNA positive, out of 43 anti-HBc negative (23%), with a statistical significance of <it>p </it>= 0.03. Viral DNA and HBsAg were present intermittently in follow up sera of 13 individuals. Sequence analysis in the core region of the amplified DNA products showed that all the strains belonged to HBV genotype F3. The OBI isolates displayed 96-100% nucleotide identity between them. One isolate exhibited the co-circulation of a wild type variant with a variant with a premature stop codon at the core protein, and a variant exhibiting a deletion of 28 amino acids.</p> <p>Conclusions</p> <p>The frequency of OBI found in this Amerindian group warrants further studies in other communities exhibiting different degrees of HBV exposure.</p

Etiology and Viral Genotype in Patients with End-Stage Liver Diseases admitted to a Hepatology Unit in Colombia

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the principal risk factor associated to end-stage liver diseases in the world. A study was carried out on end-stage liver disease cases admitted to an important hepatology unit in Medellin, the second largest city in Colombia. From 131 patients recruited in this prospective study, 71% of cases were diagnosed as cirrhosis, 12.2% as HCC, and 16.8% as cirrhosis and HCC. Regarding the risk factors of these patients, alcohol consumption was the most frequent (37.4%), followed by viral etiology (17.6%). Blood and/or hepatic tissue samples from patients with serological markers for HCV or HBV infection were characterized; on the basis of the phylogenetic analysis of HCV 5′ UTR and HBV S gene, isolates belonged to HCV/1 and HBV/F3, respectively. These results confirm the presence of strains associated with poor clinical outcome, in patients with liver disease in Colombia; additionally, HBV basal core promoter double mutant was identified in HCC cases. Here we show the first study of cirrhosis and/or HCC in Colombian and HBV and HCV molecular characterization of these patients. Viral aetiology was not the main risk factor in this cohort but alcohol consumption

Antiviral activity of flavonoids present in aerial parts of Marcetia taxifolia against Hepatitis B virus, Poliovirus, and Herpes Simplex Virus in vitro

Marcetia taxifolia is a neotropical plant present in South America and it has been evaluated in several biological models due to the presence of active metabolites. Nevertheless, there is a limited quantity of studies related to the antiviral activity of the compounds present in this genus. In our work, the antiviral effect of the compounds isolated from the aerial parts of Marcetia taxifolia was evaluated against Hepatitis B virus (HBV), Herpes Simplex Virus type 1 (HSV-1), and Poliovirus type 1 (PV-1). The cytopathic effect and viral quantification by qPCR were determined as indicative of antiviral activity. Our data show that myricetin rhamnoside (MyrG), myricetin-3-α-O-ramnosil (1→6)-α-galactoside (MyrGG), 5,3'-dihydroxy-3,6,7,8,4’-pentamethoxyflavone (PMF), 5-hydroxy-3,6,7,3',4'pentamethoxyflavone (PMF-OH) had antiviral activity without cytotoxic effects. The methoxyflavones PMF and PMF-OH were the most active compounds, showing an antiviral effect against all the evaluated viruses. Computational studies showed that these compounds could interact with the Reverse Transcriptase. Altogether, these results suggest that the flavonoids (related to myricetin and methoxyflavones) are the main antiviral compounds present in the aerial parts of Marcetia taxifolia. Furthermore, our results showed that the methoxyflavones have a broad antiviral activity, which represents an opportunity to evaluate these flavonoids as lead molecules to develop new antiviral compounds

Genetic history of Hepatitis C virus in Venezuela: high diversity and long time of evolution of HCV genotype 2

Background: The subtype diversity of the hepatitis C virus (HCV) genotypes is unknown in Venezuela. Methodology/Principal Findings: Partial sequencing of the NS5B region was performed in 310 isolates circulating in patients from 1995 to 2007. In the samples collected between 2005 and 2007, HCV genotype 1 (G1) was the most common genotype (63%), composed as expected of mainly G1a and G1b. G2 was the second most common genotype (33%), being G2a almost absent and G2j the most frequent subtype. Sequence analysis of the core region confirmed the subtype assignment performed within the NS5b region in 63 isolates. The complete genome sequence of G2j was obtained. G2j has been described in France, Canada and Burkina Fasso, but it was not found in Martinique, where several subtypes of G2 circulate in the general population. Bayesian coalescence analysis indicated a most recent common ancestor (MRCA) of G2j around 1785, before the introduction of G1b (1869) and G1a (1922). While HCV G1a and G1b experienced a growth reduction since 1990, coincident with the time when blood testing was implemented in Venezuela, HCV G2j did not seem to reach growth equilibrium during this period. Conclusions/Significance: Assuming the introduction of G2j from Africa during the slave trade, the high frequency of G2j found in Venezuela could suggest: 1- the introduction of African ethnic groups different from the ones introduced to Martinique or 2- the occurrence of a founder effect. This study represents an in-depth analysis of the subtype diversity of HCV in Venezuela, which is still unexplored in the Americas and deserves further studies.Fil: Sulbarán, Maria Z.. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Di Lello, Federico Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Virología; ArgentinaFil: Sulbarán, Yoneira. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Cosson, Clarisa. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Loureiro, Carmen. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Rangel, Héctor R.. Instituto Venezolano de Investigaciones Cientificas; VenezuelaFil: Cantaloube, Jean F.. Etablissement Français du Sang Alpes-Méditerranée. Unité Emergence et Co-évolution virale; FranciaFil: Campos, Rodolfo Hector. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Virología; ArgentinaFil: Moratorio, Gonzalo. Universidad de la Republica; Uruguay. Instituto Pasteur de Montevideo; UruguayFil: Cristina, Juan. Universidad de la Republica; UruguayFil: Pujol, Flor H.. Instituto Venezolano de Investigaciones Cientificas; Venezuel

Performance of molecular methods for identification of unusual subtypes of hepatitis C virus genotype 2

Introduction: Hepatitis C virus (HCV) displays high genetic variability, with seven genotypes and numerous subtypes. The determination of the viral type has been essential for the selection and timing of antiviral treatment. In Venezuela, HCV genotype 2 is relatively diverse, being particularly prevalent subtype 2j. Objective: To evaluate the performance of methodologies for genotyping HCV, particularly for identification of subtype 2j. Materials and methods: HCV genotype and subtype were determined by reverse hybridization technique (LiPA) and sequencing of the HCV 5’UTR and NS5B regions. Results: A total of 65 samples from HCV-infected patients were analyzed. PCR amplifications of the 5’UTR region exhibited the highest sensitivity (100% vs 91% for LiPA and 77% for NS5B). Genotype determination, taking as reference test NS5B, showed 100% concordance with the other methods, and 67% and 59% for subtypes with 5´NC and LiPA, respectively. NS5B sequencing allowed the identification of subtypes 2j and 2s, which were not detected by the other methods. A specific LiPA pattern was not observed for HCV subtype 2j. Conclusion: Although being the methodology with lowest sensitivity for amplification of HCV RNA, sequencing NS5B region remains a powerful tool for correct discrimination of the different HCV subtypes, which is of epidemiological relevance

Diversidad mitocondrial en el nor-occidente de venezuela. implicaciones para probables rutas migratorias prehispánicas

RESUMEN La utilidad del ADN mitocondrial (ADNmt) para determinar afinidad genética entre grupos indígenas contemporáneos e inferir sobre migraciones, ha sido demostrada; pero la imposibilidad de estudiar grupos prehispánicos extintos, limita las inferencias sobre migraciones en esa época. El mestizaje en poblaciones neoamericanas ha sido caracterizado por uniones entre hombres europeos y mujeres indígenas, permitiendo detectar en la población contemporánea haplogrupos mitocondriales amerindios que informan sobre poblaciones extintas. Para conocer los linajes femeninos en el occidente de Venezuela, se estudiaron los haplogrupos del ADNmt a partir de RFLP, en una muestra de 193 individuos con antepasados procedentes del occidente de Venezuela, 81 del Estado Lara (Barquisimeto) y 112 de tres pueblos del Estado Falcón (Macu-quita=25, Macanillas=29 y Churuguara=58). Se comparó la distribución de haplogrupos entre las poblaciones y se estimó el mestizaje por línea femenina en ellas. Se comparó la distribución de cuatro haplogrupos indígenas con otras regiones de América. Se observa que en las cuatro poblaciones predominan haplogrupos amerindios, seguidos de los africanos. Al comparar la fracción indígena con el resto de América encontramos que Macanillas, Lara y Churuguara se asemejan a grupos de Amazonas y Suramérica, mientras que Macuquita a Aruba. Esto sugiere una diversidad genética importante en esa zona como probable ruta de paso hacia el sur y el Caribe; además refleja vínculos genéticos importantes entre grupos prehispánicos de Aruba y los de la Península de Paraguaná. Evidencias arqueológicas soportan estos postulados. Se recomienda aumentar la muestra y realizar análisis de secuencias para un nivel mayor de precisión. Palabras clave: ADN mitocondrial, haplogrupos, población venezolana, grupos indígenas. ABSTRACT Mitocondrial DNA (mtDNA) has been widely used to study genetic relationships between contemporary Amerindian groups and to infer ancestral migration movements; however inferences about migration routes of prehispanic extinct groups are difficult. Admixture of Neoamerican groups has been characterized by unions between European males and Amerindian females. This allows the identification in present populations of Amerindian mitocondrial haplogroups which give information on ancestral groups. In order to investigate female lineages present in western Venezuela, RFLP haplogroups from mtDNA were obtained from 193 individuals with grandparents from this region, 81 from the State of Lara (Barquisimeto) and 112 from 3 towns of the State of Falcon (Macuquita=25; Macanilla=29 and Churuguara=58). Comparison of haplogroup distributions between groups was performed, and admixture estimates based on female lineages were obtained. The distribution of four Amerindian haplogroups was compared with those of other populations from the American Continent. In our four samples Amerindian haplogroups predominate, followed by those of African origin. In the comparison of the mtDNA Amerindian fraction with other populations we find that Macanillas, Lara and Churuguara are similar to South American and Amazonian groups whilst Macuquita is similar to groups from Aruba. Our findings suggest an important genetic diversity in this region, explained by migration routes to and from the south and the Caribean. They also suggest genetic relationship between prehispanic groups from Aruba and those from the Paraguaná peninsula, which have been inferred by archeological evidences. An increase in sample size and analysis of sequences for more precision is recommended. Key words: Mitocondrial DNA, haplogroups, Venezuelan population, Amerindians

World Society for Virology first international conference: Tackling global virus epidemics

This communication summarizes the presentations given at the 1st international conference of the World Society for Virology (WSV) held virtually during 16–18 June 2021, under the theme of tackling global viral epidemics. The purpose of this biennial meeting is to foster international collaborations and address important viral epidemics in different hosts. The first day included two sessions exclusively on SARS-CoV-2 and COVID-19. The other two days included one plenary and three parallel sessions each. Last not least, 16 sessions covered 140 on-demand submitted talks. In total, 270 scientists from 49 countries attended the meeting, including 40 invited keynote speakers.Peer reviewe

World Society for Virology first international conference: Tackling global virus epidemics.

Funder: Department of Health, Australian GovernmentThis communication summarizes the presentations given at the 1st international conference of the World Society for Virology (WSV) held virtually during 16-18 June 2021, under the theme of tackling global viral epidemics. The purpose of this biennial meeting is to foster international collaborations and address important viral epidemics in different hosts. The first day included two sessions exclusively on SARS-CoV-2 and COVID-19. The other two days included one plenary and three parallel sessions each. Last not least, 16 sessions covered 140 on-demand submitted talks. In total, 270 scientists from 49 countries attended the meeting, including 40 invited keynote speakers