Efficacy of oseltamivir compared with zanamivir in COPD patients with seasonal influenza virus infection: a randomized controlled trial

Influenza viruses exacerbate chronic obstructive pulmonary disease (COPD) with considerable morbidity and mortality. Zanamivir and oseltamivir are effective in treating influenza. However, their efficacy in relieving influenza symptoms in COPD patients remains unknown, with the lack of controlled trials in this subject. Therefore, we conducted this randomized controlled trial to investigate the clinical efficacy of both interventions in this population. Patients were allocated to two groups (80 patients each): oseltamivir (OSELTA) and zanamivir (ZANA) groups. Oseltamivir (75 mg) was orally administered twice daily for 5 days, while zanamivir (10 mg) was inhaled twice daily for 5 days. Clinical parameters including body temperature, influenza symptoms (i.e., sore throat, cough, etc.), and serial blood tests were recorded on days 1, 3, and 7. We analyzed primary (changes in body temperature) and secondary outcomes (changes in non-specific symptoms) using the pre-protocol and intention-to-treat analyses. Differences between groups were assessed using t-test. Oseltamivir and zanamivir significantly reduced body temperature on the 3rd day after treatment; however, the number of patients who reported clinical improvement in influenza-like symptoms was significantly higher in the OSELTA group compared to the ZANA group on days 3 (85 vs 68.8%, P=0.015) and 7 (97.5 vs 83.8%, P=0.003). However, no significant changes in hematological (white blood cells and its subtypes) and inflammatory (C-reactive protein) parameters were noted (P>0.05). Our results suggested that oseltamivir and zanamivir are effective in reducing body temperature, while oseltamivir led to better clinical improvement regarding influenza-like symptoms in patients with COPD.

A Therapeutic Oral Vaccine Candidate against Propionibacterium acnes: Preparation and Immunological Evaluation of Nanoparticles Encapsulated Sialidase-CAMP Fusion Protein

Abstract Acne Vulgaris is a common skin disease caused by Propionibacterium acnes, an anaerobic microbiota of human skin that plays a vital role in the pathology of acne. The aim of this study was to prepare nanoparticles containing an acne recombinant protein and determine its ability as an oral acne vaccine in mice. The recombinant Sialidase-CAMP gene was expressed and purified in a prokaryotic host. The chitosan nanoparticles containing the recombinant protein were prepared, encapsulated, and administered by both oral and subcutaneous routes to Balb/c mice. Sera IgA and IgG and stool IgA titers were measured by ELISA, and the immunized mice were challenged against P. acnes. A 65 kDa recombinant protein was confirmed by SDS-PAGE and western blot. The size and zeta potential of nanoparticles were 80 nm and +18 mV, respectively. After oral immunization, the serum IgG and IgA titers were 1:3200 and 1:16, respectively, and the stool IgA titer was 1:8. In the subcutaneous route, the serum IgG titer was 1:51200. Immunized mice showed no inflammation in the ear of challenged mice. It is the first study that examines a chitosan-nanoparticulated acne fusion protein as an applicable acne vaccine candidate with appropriate immunogenicity potential. Further studies are required to validate the clinical usefulness of this vaccine candidate.

El escándalo de la cloroquina / The chloroquine scandal

El autor aborda el caso de la cloroquina y la hidroxicloroquina en el contexto de la actual pandemia de COVID-19, a través de dos ejes centrales. Por un lado, el escándalo a nivel editorial y de comunicación de la evidencia, y por otro, el de la toma de decisiones en salud pública. Describe flagrantes debilidades en la cadena de generación, difusión y aplicación del nuevo conocimiento. Adicionalmente, explora iniciativas y propuestas que podrían contribuir a solucionar estos problemas. (AU)

The author addresses the case of chloroquine and hydroxychloroquine in the context of the current COVID-19 pandemic, through two central axes. On the one hand, the scandal at the editorial and communication level of the evidence, and on the other, that of decision-making in public health. He describes flagrant weaknesses in the chain of generation, diffusion,and application of new knowledge. Additionally, it explores initiatives and proposals that could contribute to solving these problems. (AU)

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.

Surveillance of antiviral resistance markers in Argentina: detection of E119V neuraminidase mutation in a post-treatment immunocompromised patient

Although vaccines are the best means of protection against influenza, neuraminidase inhibitors are currently the main antiviral treatment available to control severe influenza cases. One of the most frequent substitutions in the neuraminidase (NA) protein of influenza A(H3N2) viruses during or soon after oseltamivir administration is E119V mutation. We describe the emergence of a mixed viral population with the E119E/V mutation in the NA protein sequence in a post-treatment influenza sample collected from an immunocompromised patient in Argentina. This substitution was identified by a real-time reverse transcriptase polymerase chain reaction (RT-PCR) protocol and was confirmed by direct Sanger sequencing of the original sample. In 2014, out of 1140 influenza samples received at the National Influenza Centre, 888 samples (78%) were A(H3N2) strains, 244 (21.3%) were type B strains, and 8 (0.7%) were A(H1N1)pdm09 strains. Out of 888 A(H3N2) samples, 842 were tested for the E119V substitution by quantitative RT-PCR: 841 A(H3N2) samples had the wild-type E119 genotype and in one sample, a mixture of viral E119/ V119 subpopulations was detected. Influenza virus surveillance and antiviral resistance studies can lead to better decisions in health policies and help in medical treatment planning, especially for severe cases and immunocompromised patients.

Bacterial vaginosis in pregnant adolescents: proinflammatory cytokine and bacterial sialidase profile. Cross-sectional study / Vaginose bacteriana em gestantes adolescentes: perfil de citocinas proinflamatórias e sialidases bacterianas. Estudo transversal

ABSTRACT CONTEXT AND OBJECTIVE: Bacterial vaginosis occurs frequently in pregnancy and increases susceptibility to sexually transmitted infections (STI). Considering that adolescents are disproportionally affected by STI, the aim of this study was to evaluate the cervicovaginal levels of interleukin (IL)-1 beta, IL-6, IL-8 and bacterial sialidase in pregnant adolescents with bacterial vaginosis. DESIGN AND SETTING: Cross-sectional study at mother and child referral units in Belém, Pará, Brazil. METHODS: Vaginal samples from 168 pregnant adolescents enrolled were tested for trichomoniasis and candidiasis. Their vaginal microbiota was classified according to the Nugent criteria (1991) as normal, intermediate or bacterial vaginosis. Cervical infection due to Chlamydia trachomatisand Neisseria gonorrhoeae was also assessed. Cytokine and sialidase levels were measured, respectively, using enzyme-linked immunosorbent assays and MUAN conversion in cervicovaginal lavages. Forty-eight adolescents (28.6%) were excluded because they tested positive for some of the infections investigated. The remaining 120 adolescents were grouped according to vaginal flora type: normal (n = 68) or bacterial vaginosis (n = 52). Their cytokine and sialidase levels were compared between the groups using the Mann-Whitney test (P < 0.05). RESULTS: The pregnant adolescents with bacterial vaginosis had higher levels of IL-1 beta, IL-6 and IL-8 (P < 0.05). Sialidase was solely detected in 35 adolescents (67.2%) with bacterial vaginosis. CONCLUSIONS: Not only IL-1 beta and sialidase levels, but also IL-6 and IL-8 levels are higher in pregnant adolescents with bacterial vaginosis, thus indicating that this condition elicits a more pronounced inflammatory response in this population, which potentially increases vulnerability to STI acquisition.

RESUMO CONTEXTO E OBJETIVO: A vaginose bacteriana é uma condição, comum em gestantes, que aumenta a susceptibilidade a infecções sexualmente transmissíveis (IST). Considerando que adolescentes são desproporcionalmente afetadas por IST, o objetivo deste estudo foi avaliar os níveis cervicovaginais de interleucina (IL)-1 beta, IL-6, IL-8 e sialidases bacterianas em gestantes adolescentes com vaginose bacteriana. DESENHO DO ESTUDO E LOCAL: Estudo transversal em Unidade de Referência Materno Infantil (UREMIA), Belém, Pará, Brasil. MÉTODOS: Amostras vaginais das 168 gestantes adolescentes incluídas foram testadas para tricomoníase e candidíase e a microbiota vaginal foi classificada em normal, intermediária e vaginose bacteriana, segundo os critérios de Nugent (1991). Infecções cervicais por Chlamydia trachomatis eNeisseria gonorrhoeae também foram avaliadas. Os níveis de citocinas e sialidades foram quantificados, respectivamente, por método imunoenzimático e pela conversão do MUAN nos lavados cervicovaginais. Foram excluídas 48 (28,6%) adolescentes positivas para alguma das infecções investigadas. As 120 gestantes remanescentes foram agrupadas de acordo com o padrão de flora vaginal em: normal (n = 68) e vaginose bacteriana (n = 52). Níveis de citocinas e sialidases foram comparados pelo teste de Mann-Whitney, P < 0,05. RESULTADOS: As gestantes adolescentes com vaginose bacteriana entre os grupos apresentaram níveis aumentados de IL-1 beta, IL-6 and IL-8 (P < 0,05). Sialidases foram exclusivamente detectadas em 35 (67,2%) adolescentes com vaginose bacteriana. CONCLUSÕES: Não apenas a IL-1 beta e as sialidases estão aumentadas em gestantes adolescentes com vaginose bacteriana, mas também IL-6 e IL-8, indicando resposta inflamatória mais pronunciada dessa alteração de microbiota nesta população, potencializando a vulnerabilidade à aquisição de IST.

Alcohol consumption and burden of disease in the Americas in 2012: implications for alcohol policy / El consumo de alcohol y la carga de morbilidad en la región de las Américas en el 2012: implicaciones para las políticas relacionadas con el consumo de alcohol

OBJECTIVE:To describe the volume and patterns of alcohol consumption up to and including 2012, and to estimate the burden of disease attributable to alcohol consumption as measured in deaths and disability-adjusted life years (DALYs) lost in the Americas in 2012. METHODS: Measures of alcohol consumption were obtained from the World Health Organization (WHO) Global Information System on Alcohol and Health (GISAH). The burden of alcohol consumption was estimated in both deaths and DALYs lost based on mortality data obtained from WHO, using alcohol-attributable fractions. Regional groupings for the Americas were based on the WHO classifications for 2004 (according to child and adult mortality). RESULTS: Regional variations were observed in the overall volume of alcohol consumed, the proportion of the alcohol market attributable to unrecorded alcohol consumption, drinking patterns, prevalence of drinking, and prevalence of heavy episodic drinking, with inhabitants of the Americas consuming more alcohol (8.4 L of pure alcohol per adult in 2012) compared to the world average. The Americas also experienced a high burden of disease attributable to alcohol consumption (4.7% of all deaths and 6.7% of all DALYs lost), especially in terms of injuries attributable to alcohol consumption. CONCLUSIONS: Alcohol is consumed in a harmful manner in the Americas, leading to a high burden of disease, especially in terms of injuries. New cost-effective alcohol policies, such as increasing alcohol taxation, increasing the minimum legal age to purchase alcohol, and decreasing the maximum legal blood alcohol content while driving, should be implemented to decrease the harmful consumption of alcohol and the resulting burden of disease.

OBJETIVO:Describir el volumen y los modelos de consumo de alcohol hasta el año 2012 incluido, y calcular la carga de morbilidad atribuible al consumo de alcohol medida según el número de defunciones y los años de vida ajustados en función de la discapacidad (AVAD) perdidos en la Región de las Américas en el 2012. MÉTODOS: Los datos sobre el consumo de alcohol se obtuvieron a partir del Sistema Mundial de Información sobre el Alcohol y la Salud (GISAH, por sus siglas en inglés) de la Organización Mundial de la Salud (OMS). La carga del consumo de alcohol se calculó según la mortalidad y según los AVAD perdidos con base en los datos de mortalidad obtenidos de la OMS, tomando en consideración las fracciones atribuibles al alcohol. La división en subregiones se basó en las clasificaciones de la OMS del año 2004 (según la mortalidad en niños y adultos). RESULTADOS: Se observaron variaciones regionales en el volumen total de alcohol consumido, la proporción del mercado del alcohol atribuible al consumo de alcohol no registrado, los hábitos de consumo, la prevalencia del consumo y la prevalencia de los episodios de consumo excesivo de alcohol. Los habitantes de la Región de las Américas consumieron más alcohol (8,4 litros de alcohol puro por adulto en el 2012) en comparación con el promedio mundial. La Región también experimentó una alta carga de morbilidad atribuible al consumo de alcohol (4,7% de las defunciones y 6,7% de los AVAD perdidos), especialmente en forma de lesiones atribuibles al consumo de alcohol. CONCLUSIONES: El alcohol se consume de una manera perjudicial en la Región de las Américas y ello comporta una alta carga de morbilidad, especialmente en forma de lesiones. Con objeto de disminuir el consumo perjudicial de bebidas alcohólicas y la carga de morbilidad resultante, es preciso introducir nuevas políticas en materia de consumo de alcohol que sean eficaces en función de los costos, tales como el incremento de los impuestos sobre el alcohol, el aumento de la edad mínima legal para adquirir alcohol, y la disminución de la concentración máxima legal de alcohol en sangre mientras se conduce.

Molecular findings from influenza A(H1N1)pdm09 detected in patients from a Brazilian equatorial region during the pandemic period

After the World Health Organization officially declared the end of the first pandemic of the XXI century in August 2010, the influenza A(H1N1)pdm09 virus has been disseminated in the human population. In spite of its sustained circulation, very little on phylogenetic data or oseltamivir (OST) resistance is available for the virus in equatorial regions of South America. In order to shed more light on this topic, we analysed the haemagglutinin (HA) and neuraminidase (NA) genes of influenza A(H1N1)pdm09 positive samples collected during the pandemic period in the Pernambuco (PE), a northeastern Brazilian state. Complete HA sequences were compared and amino acid changes were related to clinical outcome. In addition, the H275Y substitution in NA, associated with OST resistance, was investigated by pyrosequencing. Samples from PE were grouped in phylogenetic clades 6 and 7, being clustered together with sequences from South and Southeast Brazil. The D222N/G HA gene mutation, associated with severity, was found in one deceased patient that was pregnant. Additionally, the HA mutation K308E, which appeared in Brazil in 2010 and was only detected worldwide the following year, was identified in samples from hospitalised cases. The resistance marker H275Y was not identified in samples tested. However, broader studies are needed to establish the real frequency of resistance in this Brazilian region.

Neuraminidase inhibitors for preventing and treating influenza in healthy adults and children

BACKGROUND: Neuraminidase inhibitors (NIs) are stockpiled and recommended by public health agencies for treating and preventing seasonal and pandemic influenza. They are used clinically worldwide. OBJECTIVE: To describe the potential benefits and harms of NIs for influenza in all age groups by reviewing all clinical study reports of published and unpublished randomised, placebo-controlled trials and regulatory comments. METHODS Search methods: We searched trial registries, electronic databases (to 22 July 2013) and regulatory archives, and corresponded with manufacturers to identify all trials. We also requested clinical study reports. We focused on the primary data sources of manufacturers but we checked that there were no published randomised controlled trials (RCTs) from non-manufacturer sources by running electronic searches in the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, MEDLINE (Ovid), EMBASE, Embase.com, PubMed (not MEDLINE), the Database of Reviews of Effects, the NHS Economic Evaluation Database and the Health Economic Evaluations Database. Selection criteria: Randomised, placebo-controlled trials on adults and children with confirmed or suspected exposure to naturally occurring influenza. Data collection and analysis: We extracted clinical study reports and assessed risk of bias using purpose-built instruments. We analysed the effects of zanamivir and oseltamivir on time to first alleviation of symptoms, influenza outcomes, complications, hospitalisations and adverse events in the intention-to-treat (ITT) population. All trials were sponsored by the manufacturers. MAIN RESULTS: We obtained 107 clinical study reports from the European Medicines Agency (EMA), GlaxoSmithKline and Roche. We accessed comments by the US Food and Drug Administration (FDA), EMA and Japanese regulator. We included 53 trials in Stage 1 (a judgement of appropriate study design) and 46 in Stage ...

Oseltamivir-resistant influenza A(H1N1)pdm09 virus in southern Brazil

The neuraminidase (NA) genes of A(H1N1)pdm09 influenza virus isolates from 306 infected patients were analysed. The circulation of oseltamivir-resistant viruses in Brazil has not been reported previously. Clinical samples were collected in the state of Rio Grande do Sul (RS) from 2009-2011 and two NA inhibitor-resistant mutants were identified, one in 2009 (H275Y) and the other in 2011 (S247N). This study revealed a low prevalence of resistant viruses (0.8%) with no spread of the resistant mutants throughout RS.

Virological surveillance and antiviral resistance of human influenza virus in Argentina, 2005–2008 / Vigilancia virológica y resistencia a los antivíricos del virus de la gripe humana en la Argentina, 2005–2008

Objective. To describe the virological characteristics of the influenza strains circulating in Argentina in 2005–2008 and to assess the prevalence of antiviral resistance. Methods. On the basis of their geographical spread and prevalence, influenza A and B isolates grown in Madin–Darby canine kidney cells were selected after antigenic and genomic characterization to be analyzed for antiviral resistance by enzymatic assay and pyrosequencing. Amantadine susceptibility was evaluated by pyrosequencing for known resistance markers on 45 strains of influenza A. Susceptibility to oseltamivir and zanamivir was evaluated by enzymatic assay of 67 influenza A and 46 influenza B strains, some of which were further analyzed by sequencing the neuraminidase gene. Results. Resistance to amantadine was observed only on A(H3N2) strains (29/33); all of them carried the mutation S31N in their M2 sequence. Oseltamivir resistance was observed in 12 (34.3%) of the 35 A(H1N1) strains from 2008; all of them carried the mutation H275Y in their neuraminidase sequence. All these viruses remained sensitive to zanamivir. Conclusions. This study describes a high incidence of amantadine-resistant influenza A(H3N2) viruses since 2006 and an unprecedented increase in oseltamivir resistance detected only in influenza A(H1N1) viruses isolated in 2008. Influenza A and B viruses were more sensitive to oseltamivir than to zanamivir, and influenza A viruses were more sensitive to both neuraminidase inhibitors than the influenza B viruses. The national data generated and analyzed in this study may help increase knowledge about influenza antiviral drug resistance, which is a problem of global concern.

Objetivo. Describir las características virológicas de las cepas de virus de la gripe que circulaban en la Argentina entre el 2005 y el 2008, y evaluar la prevalencia de la resistencia a los antivíricos. Métodos. Según su diseminación geográfica y su prevalencia, se seleccionaron aislados de gripe A y B cultivados en células renales caninas de Madin-Darby después de su caracterización antigénica y genómica, y se analizó su resistencia a los antivíricos mediante análisis enzimático y pirosecuenciación. La sensibilidad a la amantadina se evaluó por pirosecuenciación para los marcadores conocidos de resistencia en 45 cepas de gripe A. La sensibilidad al oseltamivir y al zanamivir se evaluó mediante análisis enzimático de 67 cepas de gripe A y 46 cepas de gripe B, algunas de las cuales se analizaron en mayor profundidad mediante la secuenciación del gen de la neuraminidasa. Resultados. Se observó resistencia a la amantadina solo en las cepas de gripe A (H3N2) (29/33); todas ellas tenían la mutación S31N en su secuencia de M2. Se observó resistencia al oseltamivir en 12 (34,3%) de las 35 cepas de gripe A (H1N1) aisladas en el 2008; todas ellas tenían la mutación H275Y en su secuencia de neuraminidasa. Todos estos virus conservaron su sensibilidad al zanamivir. Conclusiones. En este estudio se describe una incidencia elevada del virus de la gripe A (H3N2) resistente a la amantadina desde el 2006 y un aumento sin precedentes de la resistencia al oseltamivir detectada solo en los virus de la gripe A (H1N1) aislados en el 2008. Los virus de la gripe A y B fueron más sensibles al oseltamivir que al zanamivir y los virus de la gripe A fueron más sensibles a ambos inhibidores de la neuraminidasa que los virus de la gripe B. Los datos nacionales generados y analizados en este estudio pueden ayudar a aumentar los conocimientos acerca de la resistencia a los fármacos antivíricos dirigidos contra el virus de la gripe, lo que es un motivo de preocupación mundial.

Reactividad del antígeno GST-SAPA de Trypanosoma cruzi frente a sueros de pacientes con enfermedad de Chagas y leishmaniasis / Reactivity of GST-SAPA antigen of Trypanosoma cruzi against sera from patients with Chagas disease and leishmaniasis

El diagnóstico serológico de la infección producida por Trypanosoma cruzi es de especial relevancia dado que los métodos parasitológicos tienen, en las fases indeterminada y crónica, una sensibilidad limitada. El antígeno SAPA fue usado en diversos estudios y demostró ser un buen candidato para el diagnóstico de la infección por T. cruzi. La enfermedad de Chagas y la leishmaniasis son endémicas en el norte de Salta, con posibles zonas de solapamiento. Este hecho suele dar lugar a infecciones mixtas T. cruzi-Leishmania spp., con la consecuente probabilidad de diagnóstico cruzado cuando se usan antígenos no específicos. Se evaluó la reactividad del antígeno GST-SAPA en la prueba de ELISA (ELISA-SAPA) frente a sueros de personas infectadas por T. cruzi (n = 154), con leishmaniasis (n = 66), infecciones mixtas (n = 29) y controles negativos (n = 28), usando como pruebas de referencia para el diagnóstico de la infección por T. cruzi kits comerciales de ELISA y HAI. Se calculó la sensibilidad, especificidad e índice de concordancia kappa de la prueba de ELISA-SAPA, para la detección de infección por T. cruzi. Entre los sueros de pacientes con leishmaniasis estudiados se detectó un 30.5% de infecciones mixtas. Para la detección de infección por T. cruzi, ELISA-SAPA mostró una sensibilidad del 97.1% (intervalo de confianza del 95%: 94.5-99.9), una especificidad del 100% (intervalo de confianza del 95%: 99.5-100) y un índice de concordancia kappa de 96 (intervalo de confianza del 95%:93-99%), comparado con las pruebas serológicas comerciales. Los valores de sensibilidad, especificidad y concordancia calculados muestran una alta eficiencia de ELISA-SAPA.

Serologic diagnosis of Trypanosoma cruzi infection is important due to the limited sensitivity of direct parasitologic methods for diagnosis in the indeterminate and chronic phases of disease. SAPA antigen has been used in several studies and has been shown to be a good marker for use in the diagnosis of T. cruzi infection. Chagas disease and leishmaniasis are endemic in northern Salta with overlapping zones of transmission, which frequently leads to T. cruzi-Leishmania spp. mixed infections. Diagnosis is complicated by the fact that there is significant cross-reactivity when non-specific antigens are used. We evaluated the reactivity of GST-SAPA antigen in the ELISA test (ELISA-SAPA) against sera from persons infected with T. cruzi (n = 154), leishmaniasis (n = 66), mixed infections (29), and healthy controls (n = 28) using commercial ELISA and IHA kits as reference tests. For ELISA-SAPA the sensitivity, specificity and kappa index were calculated for detection of T. cruzi infection. Among sera from patients infected with leishmaniasis, 30.5% of co-infections were detected. ELISA-SAPA sensitivity was 97.1% (confidence interval 95%: 94.5-99.9), specificity was 100% (confidence interval 95%: 99.4-100), and kappa index was 96% (confidence interval 95%: 93-99%), for detection of T. cruzi infection. Sensitivity, specificity and kappa indices have shown a high efficiency of ELISA-SAPA.

Análise filogenética e padronização da técnica de eletroforese em gel com gradientes desnaturantes (DGGE) para caracterização das linhagens do vírus Influenza B identificadas durante as epidemias de 2004 a 2008 / Phylogenetic analysis and standardization of denaturing gradient gel eletrophoresis (DGGE) technique for characterization of Influenza B viruses lineages detected during the 2004-2008 epidemics

Globalmente, as infecções causadas pelos vírus Influenza constituem um importante desafio a Saúde Pública. Os vírus Influenza B pertencem à família Orthomyxoviridae, o genoma viral é constituído por um RNA de fita simples e polaridade negativa. O processo de drift antigênico favorece o contínuo aparecimento de novas variantes virais, o que demanda a reformulação anual da vacina. No início década de 80, foi observada a divergência do vírus Influenza B em duas linhagens antigênica e filogeneticamente distintas: B/Victoria/2/87-like (Vic87) e B/yamagata/16/88-like (Yam88), que têm co-circulado em diferentes países. O objetivo deste estudo consiste na identificação e caracterização molecular das linhagens de Influenza B circulantes em diferentes regiões brasileiras durante as epidemias de 2004 a 2008, com base no sequenciamento dos genes Hemaglutinina (HA) e Neuraminidase (NA). Ainda, padronizamos o protocolo de Eletroforese em Gel com Gradientes Desnaturantes (DGGE), visando à rápida tipagem dos vírus B. Diferentes substituições nos genes da HA e NA foram encontradas, e evidenciamos a co-circulação de ambas as linhagens no período estudado. Contudo, não observamos a ocorrência de rearranjo gênico, e nem a emergência de cepas resistentes aos inibidores de neuraminidase, com base nos genes investigados. No período 2006-2008, observamos a adequada concordância entre as cepas circulantes e as cepas vacinas preconizadas para o uso no Hemisfério Sul. Entretanto, o mesmo não foi verdadeiro para o período 2004-2005. Finalmente, o protocolo de DGGE desenvolvido pode ser eficientemente utilizado para fins de rápida...

Tratamiento y profilaxis de influenza estacional en niños / Treatment and prophylaxis of seasonal influenza in children

Influenza es una enfermedad respiratoria que produce una importante morbi-mortalidad. La prevención más importante es la vacuna anti-influenza. El tratamiento debe indicarse en las formas moderadas a graves, en niños con factores de riesgo e inmunosuprimidos. El tratamiento es efectivo si se inicia antes de las 48 horas del comienzo de los síntomas. Los inhibidores de la neuraminidasa como oseltamivir y zanamivir son efectivos e indicados para su uso en influenza en niños. Oseltamivir esta indicado a partir del año de edad y zanamivir en mayores de 7 años como tratamiento y mayores de 5 años como profilaxis. Ambos acortan los días de enfermedad, evitan la diseminación de la enfermedad y disminuyen complicaciones como la neumonía. En influenza B la eficacia es menor. La resistencia a estos agentes es baja.

Caracterización biológica de tres aislamientos naturales del Rubulavirus porcino (México)

Biological characterization of three natural isolates of the porcine rubulavirus (Mexico). Porcine rubulavirus (PoRV) produces a neurological and reproductive syndrome in pigs called the blue-eye disease, known only from Mexico. Several isolates were grouped by the main symptoms presented during outbreaks: a) neurotropic in piglets, b) broadly neurotropic in piglets and gonadotropic in adults, and c) gonadotropic in adults. We studied some biological properties of three strains, which fall in one of each virus group: La Piedad Michoacán (LPM) and Producción Animal Cerdos 1 (PAC1) and 3 (PAC3), respectively. The analyzed viral properties are mainly related with the trans-membrane hemagglutinin-neuraminidase (HN) and fusion (F) proteins, such as cytopathic effect, hemolysis, hemagglutinating (HA) and neuraminidase (NA) activities. In the infection assays PAC1 strain presented the highest fusogenicity level; however, the most cytolytic strain was PAC3. In addition, HA and NA activities and viral genome of PAC3 strain was detected in supernatants during cell infection earlier than in the other two strains, which shows that PAC3 virions release from the host cell earlier than LPM and PAC1. Experimental determination in purified viruses shows that PAC3 presented a higher HA and NA activities; however, PAC1 shows other interesting properties, such as a high thermostability of HN and differences about substrate profile respect to LPM and PAC3. Our data suggest that NA activity is associated with the virulence of RVP. Rev. Biol. Trop. 56 (2): 487-499. Epub 2008 June 30.

El Rubulavirus porcino causa un síndrome neurológico y reproductivo en cerdos, hasta ahora reportado sólo en México. Los virus aislados se agrupan de acuerdo con los síntomas principales observados durante los brotes en: a) neutrópicos en lechones, b) neurotrópicos en lechones/gonadotrópicos en adultos y c) gonadotrópicos en adultos. En este trabajo se estudiaron tres cepas: La Piedad Michoacán (LPM) y Producción Animal "Cerdos" 1 (PAC1) y 3 (PAC3), ubicadas respectivamente en cada grupo. Las propiedades estudiadas se relacionan principalmente con dos proteínas de la envoltura viral, la hemaglutinina-neuraminidasa (HN) y la proteína de fusión (F). Se cuantificaron el efecto citopático y las actividades de hemólisis, hemaglutinación (HA) y neuraminidasa (NA). En cultivo celular la cepa PAC1 presentó una mayor actividad fusogénica, sin embargo PAC3 presentó la mayor actividad citolítica. La cepa PAC3 fue la primera en ser detectada en sobrenadante de células infectadas (HA, NA y genoma), lo que muestra que sus viriones son liberados al medio antes que las otras dos cepas. PAC3 tuvo las actividades más altas de HA y NA, sin embargo, PAC1 presentó una mayor termoestabilidad en estas actividades de HN y un perfil de substrato algo distinto de los observados para LPM y PAC3. Estos datos sugieren que la actividad de NA está relacionada con la virulencia del RVP.

Síndrome hemolítico-urêmica relacionada à infecção invasiva pelo Streptococcus pneumoniae / Hemolytic-uremic syndrome complicating invasive pneumococcal disease

OBJETIVO: A doença pneumocócica é importante problema de saúde pública e raramente há associação desta infecção com a síndrome hemolítico-urêmica (SHU) grave. O objetivo deste artigo é relatar o caso de um paciente com esta associação. DESCRIÇÃO DO CASO: Criança do sexo masculino, com 17 meses de idade, admitida no hospital com insuficiência respiratória aguda e necessitando de suporte ventilatório. O exame radiológico mostrava extensa opacidade homogênea em hemitórax direito. A hemocultura foi positiva para Streptococcus pneumoniae. Nos exames de admissão, notaram-se: hemoglobina de 6,5g/dL, 38.000 plaquetas/mm³, uréia de 79mg/dL e creatinina de 1,64mg/dL. No primeiro dia, apresentou oligoanúria e hipervolemia, necessitando de hemodiafiltração. Evoluiu com disfunção de múltiplos órgãos e óbito no sétimo dia. A necrópsia mostrou áreas extensas de necrose cortical e tubular renal, com depósito de fibrina nas arteríolas. COMENTÁRIOS: A SHU associada ao pneumococo apresenta morbidade e mortalidade elevadas. Em crianças com doença pneumocócica invasiva e acometimento hematológico ou renal grave, deve-se estar atento a esta rara complicação. Merecem investigação os seguintes aspectos relacionados à doença: a função da detecção precoce de antígenos T ativados no diagnóstico e terapêutica, o papel do fator H na patogênese, o método ideal de substituição renal e a definição do prognóstico em longo prazo.

OBJECTIVE: Pneumococcal diseases are a major public health problem. Severe hemolytic-uremic syndrome is an uncommon complication. The aim of this study is to report a child with this complication. CASE DESCRIPTION: A male child with 17 months old was admitted to the hospital, due to acute respiratory failure, needing ventilatory support. Roentgenogram demonstrated massive condensation of right lung and Streptococcus pneumonia was isolated from blood cultures. Laboratory tests showed hemoglobin level of 6.5g/dL, 38,000 platelets/mm³, blood urea nitrogen of 79mg/dL and creatinine of 1.64mg/dL. On the first day, patient developed oliguria and hypervolemia and needed hemodiafiltration. Multiple organs dysfunction syndrome was followed by death on the seventh day. Necropsy showed extensive renal cortical and tubular necrosis with fibrin deposits on arterioles. COMMENTS: Hemolytic-uremic syndrome complicating invasive pneumococcal disease has high morbidity and mortality rates. Children with pneumococcal infection and severe hematologic or renal abnormalities should be investigated. The usefulness of early recognition of T-antigen activation on diagnosis and therapeutics, the role of complement factor H in the pathology, the ideal renal replacement method and the definition of long term outcome are issues to be investigated.

Detecção do vírus da cinomose canina por RT-PCR utilizando-se oligonucleotídeos para os genes da fosfoproteína, hemaglutinina e neuraminidase / Detection of canine distemper virus by RT-PCR using oligonucleotides targeted to the phosphoprotein, hemagglutinin and neuraminidase genes

Empregou-se a técnica de reação em cadeia pela polimerase precedida de transcrição reversa para detecção do vírus da cinomose canina (CC). Para a padronização da técnica foram selecionados quatro pares de oligonucleotídeos (P1, P2, N1, H1), baseados em seqüências dos genes da fosfoproteína, neuraminidase e hemaglutinina, sendo utilizadas três cepas vacinais de vírus da CC como controles positivos. Foram analisadas três amostras isoladas de cães com cinomose e quatro amostras provenientes de cães com suspeita clínica de cinomose. Não houve amplificação nas amostras com suspeita clínica da doença. Os resultados obtidos com os oligonucleotídeos P1 e N1 foram superiores aos de H1. Os oligonucleotídeos P2 foram considerados inapropriados para a detecção do vírus da CC. Os amplicons obtidos com os oligonucleotídeos P1, N1 e H1 foram clivados com endonucleases de restrição, sendo os perfis das amostras virais comparados aos da amostra vacinal Lederle, utilizada como referência. Um padrão similar de restrição foi observado em todas as amostras analisadas

The reverse transcription-polymerase chain reaction was used to detect canine distemper virus (CDV). Four oligonucleotide pairs were selected (P1, P2, N1, H1), based on the sequences of the phosphoprotein, hemagglutinin and nuraminidase genes for assay standardization, and three CDV vaccine strains were used as positive controls. Three viral isolates from dogs with canine distemper and four samples from animals clinically suspected of distemper were analysed. No amplification was detected in suspected samples. Results obtained by using P1 and N1 oligonucleotides were superior to those with H1 ones. P2 oligonucleotides were considered inadequate for CDV detection. Amplicons resulting from amplification of P1, N1 and H1 oligonucleotides were submitted to cleavage by restriction endonucleases and restriction patterns of viral samples were compared to that of Lederle strain used as reference. A similar restriction pattern was observed in all analysed samples

The non-palindromic adaptor-PCR method for the identification of the T-cell receptor genes of an interferon-gamma-secreting T-cell hybridomaspecific for trans-sialidase, an immunodominant Trypanosoma cruzi antigen

Cloning of the T-cell receptor genes is a critical step when generating T-cell receptor transgenic mice. Because T-cell receptor molecules are clonotypical, isolation of their genes requires reverse transcriptase-assisted PCR using primers specific for each different Valpha or Vß genes or by the screening of cDNA libraries generated from RNA obtained from each individual T-cell clone. Although feasible, these approaches are laborious and costly. The aim of the present study was to test the application of the non-palindromic adaptor-PCR method as an alternative to isolate the genes encoding the T-cell receptor of an antigen-specific T-cell hybridoma. For this purpose, we established hybridomas specific for trans-sialidase, an immunodominant Trypanosoma cruzi antigen. These T-cell hybridomas were characterized with regard to their ability to secrete interferon-gamma, IL-4, and IL-10 after stimulation with the antigen. A CD3+, CD4+, CD8- interferon-gamma-producing hybridoma was selected for the identification of the variable regions of the T-cell receptor by the non-palindromic adaptor-PCR method. Using this methodology, we were able to rapidly and efficiently determine the variable regions of both T-cell receptor chains. The results obtained by the non-palindromic adaptor-PCR method were confirmed by the isolation and sequencing of the complete cDNA genes and by the recognition with a specific antibody against the T-cell receptor variable ß chain. We conclude that the non-palindromic adaptor-PCR method can be a valuable tool for the identification of the T-cell receptor transcripts of T-cell hybridomas and may facilitate the generation of T-cell receptor transgenic mice.