Construction of recombinant adenovirus expressing capsid protein of serotype O foot-and-mouth disease virus and analysis of its immunogenicity / 生物工程学报

In order to construct a recombinant replication deficient human type 5 adenovirus (Ad5) expressing a foot-and-mouth disease virus (FMDV) capsid protein, specific primers for P12A and 3B3C genes of FMDV-OZK93 were synthesized. The P12A and 3B3C genes were then amplified and connected by fusion PCR, and a recombinant shuttle plasmid pDC316-mCMV-EGFP-P12A3B3C expressing the FMDV-OZK93 capsid protein precursor P12A and 3B3C protease were obtained by inserting the P12A3B3C gene into the pDC316-mCMV-EGFP plasmid. The recombinant adenovirus rAdv-P12A3B3C-OZK93 was subsequently packaged, characterized and amplified using AdMaxTM adenovirus packaging system, and the expression was verified by infecting human embryonic kidney cell HEK-293. The humoral and cellular immunity levels of well-expressed and purified recombinant adenovirus immunized mice were evaluated. The results showed that rAdv-P12A3B3C-OZK93 could be stably passaged and the maximum virus titer reached 1×109.1 TCID50/mL. Western blotting and indirect immunofluorescence showed that rAdv-P12A3B3C-OZK93 expressed the FMDV-specific proteins P12A and VP1 in HEK-293 cells. In addition, the PK cell infection experiment confirmed that rAdv-P12A3B3C-OZK93 could infect porcine cells, which is essential for vaccination in pigs. Comparing with the inactivated vaccine group, the recombinant adenovirus could induce higher FMDV-specific IgG antibodies, γ-IFN and IL-10. This indicates that the recombinant adenovirus has good immunity for animal, which is very important for the subsequent development of foot-and-mouth disease vaccine.

Development of a Recombinase-aided Amplification Combined With Lateral Flow Dipstick Assay for the Rapid Detection of the African Swine Fever Virus / 生物医学与环境科学（英文）

OBJECTIVE@#To establish a sensitive, simple and rapid detection method for African swine fever virus (ASFV) B646L gene.@*METHODS@#A recombinase-aided amplification-lateral flow dipstick (RAA-LFD) assay was developed in this study. Recombinase-aided amplification (RAA) is used to amplify template DNA, and lateral flow dipstick (LFD) is used to interpret the results after the amplification is completed. The lower limits of detection and specificity of the RAA assay were verified using recombinant plasmid and pathogenic nucleic acid. In addition, 30 clinical samples were tested to evaluate the performance of the RAA assay.@*RESULTS@#The RAA-LFD assay was completed within 15 min at 37 °C, including 10 min for nucleic acid amplification and 5 minutes for LFD reading results. The detection limit of this assay was found to be 200 copies per reaction. And there was no cross-reactivity with other swine viruses.@*CONCLUSION@#A highly sensitive, specific, and simple RAA-LFD method was developed for the rapid detection of the ASFV.

Analysis of hemagglutinin-neuraminidase gene characteristics of human parainfluenza virus type 3 among children with acute respiratory tract infection in Qingdao city / 中华预防医学杂志

The purpose was to discuss the infection status of human parainfluenza virus type 3 (HPIV-3) in children with acute respiratory tract infection(ARTI) in Qingdao, Shandong province, and to analyze the gene characteristics of HPIV-3 hemagglutinin-neuraminidase protein (HN). This study was a cross-sectional study. A total of 1 674 throat swab samples were collected randomly from children with ARTI, in the three hospitals (Qingdao Women and Children's Hospital, West Coast Branch of Affiliated Hospital of Qingdao University, Laoshan Branch of Affiliated Hospital of Qingdao University) from January 2018 to December 2019. Multiplex real-time fluorescence RT-PCR was performed to screen HPIV-3 positive specimens. For HPIV-3 positive specimens, nested PCR was used to amplify the full-length HN gene of HPIV-3. The HN gene was sequenced and compared with the representative strains of HPIV-3 in GenBank, and the phylogenetic tree was established. As results, this study collected 1 674 samples, in which there were 90 HPIV-3 positive samples showed and the detection rate was 5.37%. Among positive specimens, the number of samples from children under 6 years old was 88, accounting for 97.78%. HPIV-3 positive cases were mainly distributed in spring and summer. The full-length sequences of 44 HPIV-3 HN genes were obtained by nested PCR method. Sequence alignment and evolutionary analysis showed that the HPIV-3HN gene belonged to the C3a and C3b branches of C3 genotype, with 30 strains of subtype C3a and 14 strains of subtype C3b. The nucleotide and amino acid homology of the amplified 44 strains of the HPIV-3 HN gene in Qingdao were 97.0%-100.0% and 98.5%-100.0%, respectively. In conclusion, from 2018 to 2019, the C3a and C3b branches of HPIV-3 C3 genotype were circulating prevalent in Qingdao, Shandong province. HN gene variation rate was low, but showed certain regional characteristics in evolution.

Vacuna Johnson & Johnson contra COVID-19: distribución mundial de la vacuna, mecanismo de acción, indicaciones, contraindicaciones y efectos secundarios. Una revisión bibliográfica / Johnson & Johnson vaccine against COVID-19: worldwide vaccine distribution, mechanism of action, indications, contraindications and side effects. A literature review

El SARS-CoV-2, causante de que estemos viviendo una pandemia mundial, tuvo sus orígenes en China, desde donde ha traspasado fronteras rápidamente, llegando a todos los rincones del mundo. Muchos han sido los equipos de investigación que se enfrentan el reto de conseguir una vacuna que logre combatir este mortal virus. Es por este motivo que en esta investigación se pretendió analizar la bibliografía referida a la vacuna Johnson & Johnson (J&J) contra COVID-19: distribución mundial de la vacuna, mecanismo de acción, indicaciones, contraindicaciones y efectos secundarios. Varios estudios demuestran que su eficacia varía de acuerdo con la edad y género de cada individuo; sin embargo, esta vacuna alcanzó un grado de certeza moderada. Los efectos adversos en su mayoría son leves y se resolvieron al cabo de dos días, siendo excepción algunos casos, ya que se registró un efecto adverso poco común denominado trombocitopenia prevalente en mujeres de 18 a 40 años, por este motivo, la FDA (Administración de Alimentos y Medicamentos de EE.UU.) recomienda la precaución en el uso de la vacuna con respecto a este efecto adverso que en algunos casos podría ser mortal (AU)

The SARS-CoV-2, which caused us to be experiencing a global pandemic, had its origins in China, from where it has crossed borders rapidly, reaching all corners of the world. Many research teams have faced the challenge of getting a vaccine to fight this deadly virus. For this reason, this research aimed to analyze the literature on the Johnson & Johnson COVID-19 vaccine: global distribution of the vaccine, mechanism of action, indications, contraindications and side effects. Several studies show that its effectiveness varies according to the age and gender of each individual, but this vaccine reached a moderate degree of certainty. The adverse effects are mostly mild and resolved within two days, with some exceptions being a rare adverse effect called prevalent thrombocytopenia in women aged 18 to 40 years. For this reason, the FDA recommends caution in the use of the vaccine with respect to this potentially fatal adverse effect in some cases (AU)

Caracterización y fisiopatología del Sars-Cov-2, Revisión de la literatura actual / Characterization and pathophysiology of sars-cov-2, actual literature review

RESUMEN La enfermedad por coronavirus 2019 (COVID-19) es causada por un nuevo betacoronavirus conocido como síndrome respiratorio agudo severo coronavirus-2 (SARS-CoV-2). Para el 22 de junio del 2021, el número de casos confirmados en todo el mundo había superado los 178 millones, con más de 3 millones de muertes. La fisiopatología de la COVID-19 a partir de la infección por SARS-CoV-2 no está del todo dilucidada. En el presente artículo se exponen los hallazgos encontrados después de la búsqueda en la literatura científica realizada en la base de datos PubMed entre octubre de 2020 y abril de 2021 en la cual se incluyeron 71 artículos, con el objetivo de la revisión fisiopatológica completa, detallada y actualizada del SARS-CoV-2, abordando temas como la caracterización y ciclo de vida del virus, el mecanismo de transmisión, la cinética viral y la respuesta inmune, junto con la dinámica fisiopatológica de la infección. MÉD.UIS.2021;34(2): 61-75.

ABSTRACT Coronavirus disease 2019 (COVID-19) is caused by a new betacoronavirus named as Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). On June 22nd, 2021, the number of confirmed cases worldwide exceeded 178 million, resulting in more than 3 million deaths. The pathophysiology of COVID-19 from the infection of SARS-CoV-2 is not entirely elucidated. This review presents the findings after the research in the scientific literature carried out in the PubMed database between October 2020 and April 2021, in which 71 articles were included, with the aim of a complete, detailed and updated pathophysiological review of SARS-CoV-2, addressing issues such as the characterization and life cycle of the virus, the transmission mechanism, viral kinetics and immune response, along with the pathophysiological dynamics of the infection. MÉD.UIS.2021;34(2): 61-75.

Sarampión / Measles

En abril de 2019, UNICEF denunció que más de 20 millones de niños en todo el mundo no habían sido vacunados y alertó sobre posibles brotes de sarampión que, por su alta contagiosidad, es la primera enfermedad en emerger entre las prevenibles mediante vacunación. De continuar el descenso en las vacunaciones, podrían reaparecer también pertussis, tétanos y otras enfermedades con menor requerimiento de cobertura para alcanzar protección poblacional. A fin de agosto de 2019 se inició en la Argentina el actual brote de sarampión. Este virus se transmite por vía respiratoria, infecta múltiples órganos e induce inmunosupresión. Su genoma consiste en ARN de cadena simple. La genotipificación se efectúa por secuenciación de un fragmento de 450 nucleótidos de la proteína N que contiene la mayor densidad de variación de nucleótidos del genoma. En Sudamérica circula el genotipo D8, y en Norteamérica hay, además, un 8% de genotipo B3. Cada persona con sarampión infecta, en promedio, otras 12-18 en una población susceptible. La vacunación confiere protección directa e indirecta, e induce tanto anticuerpos como inmunidad celular. Los recién nacidos tienen protección hasta los 6 meses por anticuerpos maternos transmitidos vía placentaria. En la Argentina, el Calendario de Vacunación incluye dos dosis de triple viral, a los 12 meses y a los 5 años, y una dosis cero (6- 11 meses de edad) en distritos con casos de enfermedad. Una dosis protege al 93% de los vacunados a los 12 meses y dos dosis al 97%, de por vida.

In April 2019, UNICEF denounced that more than 20 million children worldwide had not been vaccinated and alerted on possible outbreaks of measles which, due to the high transmissibility of this virus, is the first disease preventable by vaccination to emerge. If the decline in vaccinations continues, pertussis, tetanus and other diseases, which require less coverage to achieve population protection, may also reappear. In Argentina, the current outbreak began in late August 2019. Measles virus is transmitted by air, infects multiple organs, and is associated with immunosuppression. Its genome consists of single stranded RNA. Genotyping is carried out by sequencing a 450-nucleotide fragment of the N protein, which contains the highest density of nucleotide variation. In South America, D8 is the circulating genotype and in North America, B3 accounts for 8% of the cases. Each person with measles infects, on average, another 12-18 people in a susceptible population. Vaccination confers direct and indirect protection, and induces both antibodies and cellular immunity. Newborns are protected by maternal antibodies transmitted via the placenta, up to 6 months. In Argentina, the Vaccination Calendar includes two doses of triple viral vaccine, at 12 months and 5 years, and a zero dose (6- 11 months of age) in districts with disease cases. The protection conferred by the vaccine is 93% at 12 months with a dose, and with 2 doses 97% for life.

Cerebrospinal fluid challenges for the diagnosis of herpes simplex infection in the central nervous system / Desafios do exame do líquido cefalorraquidiano para o diagnóstico de infecção por herpes simplex no sistema nervoso central

Abstract Herpes simplex virus (HSV) is a cause of a severe disease of the central nervous system (CNS) in humans. The demonstration of specific antibodies in the cerebrospinal fluid (CSF) may contribute to the retrospective neurological diagnosis. However, the commercial immunological tests for HSV infection are for use in serum samples. Objective: The aim of the present study was to adapt a commercial kit anti-HSV IgG used for serum samples to be performed with a CSF sample. Methods: Forty CSF specimens from 38 patients with suspected CNS HSV infection were serially diluted for detecting anti-HSV IgG by enzyme immunoassay (EIA). The same samples were also analyzed with the polymerase chain reaction (PCR). Results: The sensitivity of EIA test for HSV was 5% (dilution 1:40) and 65% (dilution 1:2) in CSF, and HSV DNA PCR was 15%. The combined analysis of EIA (dilution 1:2) and PCR increased the sensitivity up to 72.5%. The inflammatory CSF was associated with positive HSV PCR. Conclusions: We demonstrated the importance to adapt serological anti-HSV IgG EIA test for CSF assays to increase the accuracy of the analysis, considering the low concentration of specific antibodies in CSF.

Resumo O vírus herpes simples (HSV) é um dos agentes causadores de uma doença grave no sistema nervoso central (SNC) em humanos. A detecção de anticorpos específicos no líquido cefalorraquidiano (LCR) pode contribuir para o diagnóstico neurológico retrospectivo. Entretanto, os testes imunológicos comerciais são para uso em amostras de soro. Objetivo: Adaptar um kit comercial sorológico anti-HSV IgG para ser utilizado no de LCR. Metodos: Quarenta amostras de LCR de 38 pacientes com suspeita de infecção por HSV no SNC foram diluídas pesquisa de anticorpos anti-HSV IgG pelo método imunoenzimático (EIA). Além disso, as mesmas amostras também foram analisadas por reação em cadeia da polimerase (PCR). Resultados: A sensibilidade do teste EIA para o HSV consistiu em 5% (diluição 1:40) e 65% (diluição 1:2) no LCR, e o PCR do DNA do HSV, 15%. A análise combinada de EIA (diluição 1:2) e PCR aumentou a sensibilidade para 72,5%. Houve associação entre presença do LCR inflamatório e PCR positiva para HSV. Conclusões: Demonstramos a importância na adaptação previa do teste sorológico anti-HSV IgG EIA para ensaios do no LCR, a fim de aumentar a acuracia da análise, considerando a baixa concentração de anticorpos específicos no LCR.

Construction of T7 RNA polymerase gene expression system in Anabaena sp. PCC 7120 for the expression of hG-CSF / 生物工程学报

The low expression rate of exogenous genes in cyanobacteria is one of the bottlenecks of cyanobacteria genetic engineering. The T7 RNA polymerase expression system has achieved the efficient expression of exogenous genes in Escherichia coli. Cyanobacteria and E. coli are both Gram-negative bacteria with high genetic homology. The construction of T7 RNA polymerase expression system in cyanobacteria may improve the expression of foreign genes. In order to construct the T7 RNA polymerase expression system in Anabaena sp. PCC 7120, methods such as overlapping extension PCR and digestion-ligation technique were used to construct a site-specific integration vector pEASY-T1-F1-TacT7RNAPCmR-F2 and a shuttle expression vector pRL-T7-hG-CSF. The site-specific integration vector is capable of expressing T7 RNA polymerase, and the shuttle expression vector expresses hG-CSF driven by the T7 promoter. Then we introduced the site-specific integration vector into the wild type cyanobacteria by electroporation and transferred the shuttle expression vector into the site-integrated transgenic cyanobacteria by triparental conjugative transfer. In the end, we identified the presence of foreign genes in cyanobacteria by PCR, tested the transcription level of foreign genes in cyanobacteria by RT-PCR, and detected the protein expression of foreign genes in cyanobacteria by Western blotting. The two vectors were successfully constructed, the T7 RNA polymerase gene and hG-CSF gene were transferred into cyanobacteria well, and both genes were also expressed in cyanobacteria. In summary, the T7 RNA polymerase expression system was successfully constructed in cyanobacteria, and the expression rate of hG-CSF gene was doubled than the traditional cyanobacteria expression systems. This expression system will provide a better tool for the application of cyanobacteria genetic engineering and will promote the development of cyanobacteria as a chassis cell in the fields of synthetic biology in the future.

Durability of neutralizing antibodies and T-cell response post SARS-CoV-2 infection / 医学前沿

The ongoing pandemic of Coronavirus disease 19 (COVID-19) is caused by a newly discovered β Coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). How long the adaptive immunity triggered by SARS-CoV-2 can last is of critical clinical relevance in assessing the probability of second infection and efficacy of vaccination. Here we examined, using ELISA, the IgG antibodies in serum specimens collected from 17 COVID-19 patients at 6-7 months after diagnosis and the results were compared to those from cases investigated 2 weeks to 2 months post-infection. All samples were positive for IgGs against the S- and N-proteins of SARS-CoV-2. Notably, 14 samples available at 6-7 months post-infection all showed significant neutralizing activities in a pseudovirus assay, with no difference in blocking the cell-entry of the 614D and 614G variants of SARS-CoV-2. Furthermore, in 10 blood samples from cases at 6-7 months post-infection used for memory T-cell tests, we found that interferon γ-producing CD4

TRIM35 mediates protection against influenza infection by activating TRAF3 and degrading viral PB2

Tripartite motif (TRIM) family proteins are important effectors of innate immunity against viral infections. Here we identified TRIM35 as a regulator of TRAF3 activation. Deficiency in or inhibition of TRIM35 suppressed the production of type I interferon (IFN) in response to viral infection. Trim35-deficient mice were more susceptible to influenza A virus (IAV) infection than were wild-type mice. TRIM35 promoted the RIG-I-mediated signaling by catalyzing Lys63-linked polyubiquitination of TRAF3 and the subsequent formation of a signaling complex with VISA and TBK1. IAV PB2 polymerase countered the innate antiviral immune response by impeding the Lys63-linked polyubiquitination and activation of TRAF3. TRIM35 mediated Lys48-linked polyubiquitination and proteasomal degradation of IAV PB2, thereby antagonizing its suppression of TRAF3 activation. Our in vitro and in vivo findings thus reveal novel roles of TRIM35, through catalyzing Lys63- or Lys48-linked polyubiquitination, in RIG-I antiviral immunity and mechanism of defense against IAV infection.

The 40-91 aa sequence of porcine epidemic diarrhea virus ORF3 protein is the key structural domain controlling its location in cytoplasm / 生物工程学报

ORF3 protein, the single accessory protein encoded by porcine epidemic diarrhea virus (PEDV), is related to viral pathogenicity. In order to determine the cytoplasmic location signal of PEDV ORF3, we constructed a series of recombinant plasmids carrying full-length or truncated segments of PEDV DR13 ORF3 protein. When the acquired plasmids were transfected into Vero cells, expression and distribution of the EGFP-fused full-length ORF3 protein and its truncated forms in the cells were observed by laser confocal microscopy. The results showed that ORF3 protein or their truncated forms containing 40-91 aa segment including two transmembrane domains were localized in the cytoplasm, whereas ORF3 truncated peptides without the 40-91 aa segment were distributed in the whole cell (in both cytoplasm and nucleus). This suggests that the 40-91 aa is the key structural domain determining cytoplasmic location of PEDV ORF3 protein. The discovery provides reference for further clarifying intracellular transport and biological function of PEDV ORF3 protein.

Caracterización molecular de la nucleoproteína del virus de la rabia en canes procedentes de Arequipa, Perú / Molecular characterization of the rabies virus' nucleoprotein in dogs from Arequipa, Peru

RESUMEN Objetivos. Caracterizar la nucleoproteína (N) y establecer el origen del virus de la rabia en canes procedentes de Arequipa. Materiales y métodos. Se analizaron 30 muestras de tejido nervioso procedentes de los departamentos de Arequipa y Puno. Se extrajo el ARN total de las muestras y se sintetizó ADNc para amplificar el gen de la nucleoproteína, secuenciarlo y realizar el análisis bioinformático. Resultados. Se obtuvo la formación de un grupo definido con respecto al grupo externo (European bat lyssavirus). Este grupo fue clasificado en dos subgrupos, uno constituido por muestras procedentes de Puno y Arequipa (subgrupo A), y otro por muestras de Puno (subgrupo B), observándose una identidad nucleotídica de 99,9% en el subgrupo A. Conclusiones. Los agrupamientos de las secuencias virales muestran que los casos de rabia canina notificados en Arequipa son el resultado de la expansión de rabia canina procedente de la región endémica de Puno.

ABSTRACT Objective . To characterize the nucleoprotein (N) and establish the origin of the rabies virus in dogs coming from Arequipa. Materials and Methods. Thirty samples of nervous tissue from the departments of Arequipa and Puno were analyzed. Total RNA was extracted from the samples and cDNA was synthesized to amplify the nucleoprotein gene, sequence it, and perform bioinformatics analysis. Results . A defined group was formed with respect to the external group (European bat lyssavirus). This group was classified into two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), exhibiting a nucleotide identity of 99.9% in subgroup A. This group was classified in two subgroups, one constituted by samples coming from Puno and Arequipa (subgroup A), and another one by samples from Puno (subgroup B), observing a nucleotide identity of 99.9% in subgroup A. Conclusions. The groupings of viral sequences show that the cases of canine rabies reported in Arequipa are the result of the expansion of canine rabies from the endemic region of Puno.

Combination of mass spectrometry and GST pull-down techniques to study potential interacting protein of PCV2 ORF4 / 生物工程学报

A novel protein encoded by the open reading frame 4 (ORF4) was recently discovered in porcine circovirus type 2 (PCV2). However, little is known about the interaction proteins of ORF4 which hindered better understanding the biological functions of ORF4 in the life cycle of PCV2. In the present study, the ORF4 was inserted into the multiple cloning site of pCMV-N-Flag-GST, yielding recombinant plasmid pCMV-N-Flag-GST-ORF4. The recombinant plasmid was transfected into 293T cells and the intracellular interaction complex of ORF4 were enriched and separated by GST pull-down and SDS-PAGE, sequentially. The potential interacting proteins of PCV2 ORF4 were stained with silver and identified by mass spectrometry (MS). Finally, five candidate ORF4-interacting proteins, including Serine/threonine-protein phosphatase 6 catalytic subunit, alpha cardiac muscle 1, actin, SEC14-like protein 5 and myosin 9 were identified. These results would benefit a better understanding of the biological function of ORF4 in PCV2 infected cells.

Introducción a la virología I / Introduction to virology I

Los virus han acompañado al hombre a través de toda su historia, provocando infecciones y plagas que han generado la muerte y el temor de poblaciones completas. Muchos han sido los investigadores que han contribuido a conocer la estructura, patogenia e inmunidad involucrada. Es fundamental conocer los aspectos básicos de los virus para entender la enfermedad y el tratamiento, por lo que esperamos contribuir a esto con los apuntes que a continuación presentamos...(AU)

Viruses have accompanied humankind through their history, causing infections and producing death and fear in population. A lot of researchers have contributed to know the structure, pathogeny and immunity involved. To understand the disease and treatment is fundamental to know the basic aspects, which is the reason to present these notes...(AU)

Revisión sistemática: estrategias virales para la inducción de cáncer "virus de Epstein-Barr: latencia y mecanismos asociados a la oncogénesis viral" / Viral strategies for cancer induction "Epstein-Barr virus: latency and mechanisms associated with viral oncogenesis"

Resumen La infección crónica con virus oncogénicos es responsable de aproximadamente el 20% de todos los cánceres reportados en humanos, este proceso de oncogénesis viral presenta una naturaleza compleja, multietapa y multifactorial. Un ejemplo de ello es el Virus de Epstein- Barr (EBV), un herpesvirus que infecta de manera latente a más del 90% de la población. Aunque la infección a menudo cursa de manera asintomática, el EBV es capaz de modificar su expresión genómica estableciendo diferentes fases de latencia, alterando así el metabolismo de sus células blanco, como son los linfocitos B y las células epiteliales, proceso que resulta determinante en la aparición y desarrollo de diferentes patologías que van desde la mononucleosis infecciosa hasta procesos oncológicos como el linfoma de Burkitt, el cáncer gástrico o el cáncer nasofaríngeo.

Abstract Chronic infection with oncogenic viruses is responsible for approximately 20% of all cancers worldwide in humans, this viral transformation represents a complex, multistage and multifactorial process. An example is the Epstein-Barr virus (EBV), a herpesvirus that latently infects over 90% of the population. Although the infection often courses asymptomatically, EBV is able to modify its genomic expression by establishing different latency phases, thus altering the B lymphocytes and epithelial cells metabolism, a determinant process in the appearance and development of different pathologies ranging from infectious mononucleosis to oncological processes such as Burkitt's lymphoma, gastric cancer and nasopharyngeal cancer.

Evolution of equine influenza viruses (H3N8) during a Brazilian outbreak, 2015

Abstract Equine influenza is one of the major respiratory infectious diseases in horses. An equine influenza virus outbreak was identified in vaccinated and unvaccinated horses in a veterinary school hospital in São Paulo, SP, Brazil, in September 2015. The twelve equine influenza viruses isolated belonged to Florida Clade 1. The hemagglutinin and neuraminidase amino acid sequences were compared with the recent isolates from North and South America and the World Organisation for Animal Health recommended Florida Clade 1 vaccine strain. The hemagglutinin amino acid sequences had nine substitutions, compared with the vaccine strain. Two of them were in antigenic site A (A138S and G142R), one in antigenic site E (R62K) and another not in antigenic site (K304E). The four substitutions changed the hydrophobicity of hemagglutinin. Three distinct genetic variants were identified during the outbreak. Eleven variants were found in four quasispecies, which suggests the equine influenza virus evolved during the outbreak. The use of an out of date vaccine strain or updated vaccines without the production of protective antibody titers might be the major contributing factors on virus dissemination during this outbreak.

Hipertensión arterial pulmonar asociada al virus de inmunodeficiencia humana. A 3 décadas de su descripción / Pulmonary arterial hypertension associated with human immunodeficiency virus: thirty years after its description

Resumen El desarrollo de hipertensión arterial pulmonar asociada al virus de inmunodeficiencia humana reduce la probabilidad de sobrevivencia en el paciente afectado en comparación con el que no presenta esta alteración cardiopulmonar. La fisiopatogenia aún es incierta. Existen varias líneas de investigación para asociar las diferentes proteínas del virus en la lesión endo- telial. Desde el punto de vista terapéutico, existen modalidades de tratamiento que permiten una expectativa de vida aceptable.

Abstract The development of pulmonary arterial hypertension associated with human immunodeficiency virus reduces the probability of survival in the patient affected compared to those without cardiopulmonary disease. The pathophysiology is uncertain. There are several lines of research to associate the different proteins of the virus in the endothelial lesion. From a therapeutic point of view there are treatment modalities that allow an acceptable life expectancy.

In silico analysis of amino acid variation in human respiratory syncytial virus: insights into immunodiagnostics

BACKGROUND The highly contagious nature of human respiratory syncytial virus (HRSV) and the gravity of its infection in newborns and vulnerable adults pose a serious public health problem. Thus, a rapid and sensitive diagnostic test for viral detection that can be implemented upon the first appearance of symptoms is needed. The genetic variation of the virus must be considered for immunodiagnostic purposes. OBJECTIVES To analyse HRSV genetic variation and discuss the possible consequences for capture immunoassay development. METHODS We performed a wide analysis of N, F and G protein variation based on the HRSV sequences currently available in the GenBank database. We also evaluated their similarity with homologous proteins from other viruses. FINDINGS The mean amino acid divergences for the N, F, and G proteins between HRSV-A and HRSV-B were determined to be approximately 4%, 10% and 47%, respectively. Due to their high conservation, assays based on the full-length N and F proteins may not distinguish HRSV from human metapneumovirus and other Mononegavirales viruses, and the full-length G protein would most likely produce false negative results due to its high divergence. MAIN CONCLUSIONS We have identified specific regions in each of these three proteins that have higher potential to produce specific results, and their combined utilisation should be considered for immunoassay development.

Short interfering RNAs targeting a vampire-bat related rabies virus phosphoprotein mRNA

Abstract The aim of this study was to assess the in vitro and in vivo effects of short-interfering RNAs (siRNAs) against rabies virus phosphoprotein (P) mRNA in a post-infection treatment for rabies as an extension of a previous report (Braz J Microbiol. 2013 Nov 15;44(3):879-82). To this end, rabies virus strain RABV-4005 (related to the Desmodus rotundus vampire bat) were used to inoculate BHK-21 cells and mice, and the transfection with each of the siRNAs was made with Lipofectamine-2000™. In vitro results showed that siRNA 360 was able to inhibit the replication of strain RABV-4005 with a 1 log decrease in virus titter and 5.16-fold reduction in P mRNA, 24 h post-inoculation when compared to non-treated cells. In vivo, siRNA 360 was able to induce partial protection, but with no significant difference when compared to non-treated mice. These results indicate that, despite the need for improvement for in vivo applications, P mRNA might be a target for an RNAi-based treatment for rabies.

Características de la estructura molecular de las proteínas E del virus del Zika y E1 del virus de la rubéola y posibles implicaciones en el neurotropismo y en las alteraciones del sistema nervioso / E-ZIKV and E1-RV proteins molecular structure and their potential implications in neurotropism and nervous system disorders

Resumen Introducción. El virus del Zika (ZIKV) es un flavivirus con envoltura, transmitido a los seres humanos principalmente por el vector Aedes aegypti. La infección por ZIKV se ha asociado con un gran neurotropismo y con efectos neuropáticos, como el síndrome de Guillain-Barré en el adulto y la microcefalia fetal y posnatal, así como con un síndrome de infección congénita similar al producido por el virus de la rubéola (RV). Objetivo. Comparar las estructuras moleculares de la proteína de envoltura E del virus del Zika (E-ZIKV) y de la E1 del virus de la rubéola (E1-RV), y plantear posibles implicaciones en el neurotropismo y en las alteraciones del sistema nervioso asociadas con el ZIKV. Materiales y métodos. La secuencia de aminoácidos de la proteína E-ZIKV (PDB: 5iZ7) se alineó con la de la glucopreteína E1 del virus de la rubéola (PDB: 4ADG). Los elementos de la estructura secundaria se determinaron usando los programas Vector NTI Advance®, DSSP y POSA, así como herramientas de gestión de datos (AlignX®). Uno de los criterios principales de comparación y alineación fue la asignación de residuos estructuralmente equivalentes, con más de 70 % de identidad. Resultados. La organización estructural de la proteína E-ZIKV (PDB: 5iZ7) fue similar a la de E1-RV (PDB: 4ADG) (70 a 80 % de identidad), y se observó una correspondencia con la estructura definida para las glucoproteínas de fusión de membrana de clase II de los virus con envoltura. E-ZIKV y E1-RV exhibieron elementos estructurales de fusión muy conservados en la región distal del dominio II, asociados con la unión a los receptores celulares de entrada del virus de la rubéola (glucoproteína de mielina del oligodendrocito, Myelin Oligodendrocyte Glycoprotein, MOG), y con los receptores celulares Axl del ZIKV y de otros flavivirus. Conclusión. La comparación de las proteínas E-ZIKV y E1-RV es un paso necesario hacia la definición de otros factores moleculares determinantes del neurotropismo y la patogenia del ZIKV, el cual puede contribuir a generar estrategias de diagnóstico, prevención y tratamiento de las complicaciones neurológicas inducidas por el ZIKV.

Abstract Introduction: Zika virus (ZIKV) is an enveloped flavivirus transmitted to humans mainly by Aedes aegypti. ZIKV infection has been associated with high neurotropism and neuropathic effects such as the Guillain-Barré syndrome in adults, and fetal and postnatal microcephaly and the congenital Zika virus syndrome similar to that produced by rubella virus (VR). Objective: To compare Zika virus membrane protein E (E-ZIKV) and rubella virus membrane protein E1 (E1-RV), and to propose possible implications for neurotropism and nervous system disorders associated with ZIKV infections. Materials and methods: The amino acid sequence of E-ZIKV protein (PDB: 5iZ7) was aligned to that of rubella virus glycoprotein E1 (PDB: 4ADG). The secondary structure elements were determined using the programs Vector NTI Advance®, DSSP, and POSA, and integrated data management tools (AlignX®). One of the main comparison and alignment criteria was the allocation of structurally equivalent residues with more than 70% identity. Results: E-ZIKV structural organization (PDB: 5iZ7) was similar to that of E1-RV (PDB: 4ADG) (70%-80% identity), and it was consistent with relevant structural features of viral membrane class II fusion glycoproteins. E-ZIKV and E1-RV exhibited highly conserved fusion structural elements at the distal region of domain II, which has been associated with the RV myelin oligodendrocyte glycoprotein and Axl cell receptors in ZIKV and other flaviviruses. Conclusion: The comparison of E-ZIKV and E1-RV proteins constitutes an essential step towards the definition of ZIKV neurotropism and pathogenesis molecular determinants, and for the adoption of diagnosis, prevention and treatment strategies against neurological complications induced by ZIKV infection.