105 research outputs found

    Course of seasonal influenza A/Brisbane/59/07 H1N1 infection in the ferret

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    Every year, influenza viruses infect approximately 5-20% of the population in the United States leading to over 200,000 hospitalizations and 36,000 deaths from flu-related complications. In this study, we characterized the immune and pathological progression of a seasonal strain of H1N1 influenza virus, A/Brisbane/59/2007 in a ferret model. The immune response of the animals showed a dose-dependent increase with increased virus challenge, as indicated by the presence of virus specific IgG, IgM, and neutralizing antibodies. Animals infected with higher doses of virus also experienced increasing severity of clinical symptoms and fever at 2 days post-infection (DPI). Interestingly, weight loss was more pronounced in animals infected with lower doses of virus compared to those infected with a higher dose; these results were consistent with viral titers of swabs collected from the nares, but not the throat. Analyzed specimens included nasal and throat swabs from 1, 3, 5, and 7 DPI as well as tissue samples from caudal lung and nasal turbinates. Viral titers of the swab samples in all groups were higher on 1 and 3 DPI and returned to baseline levels by 7 DPI. Analysis of nasal turbinates indicated presence of virus at 3 DPI in all infected groups, whereas virus was only detected in the lungs of animals in the two highest dose groups. Histological analysis of the lungs showed a range of pathology, such as chronic inflammation and bronchial epithelial hypertrophy. The results provided here offer important endpoints for preclinical testing of the efficacy of new antiviral compounds and experimental vaccines

    Discutindo a educação ambiental no cotidiano escolar: desenvolvimento de projetos na escola formação inicial e continuada de professores

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    A presente pesquisa buscou discutir como a Educação Ambiental (EA) vem sendo trabalhada, no Ensino Fundamental e como os docentes desta escola compreendem e vem inserindo a EA no cotidiano escolar., em uma escola estadual do município de Tangará da Serra/MT, Brasil. Para tanto, realizou-se entrevistas com os professores que fazem parte de um projeto interdisciplinar de EA na escola pesquisada. Verificou-se que o projeto da escola não vem conseguindo alcançar os objetivos propostos por: desconhecimento do mesmo, pelos professores; formação deficiente dos professores, não entendimento da EA como processo de ensino-aprendizagem, falta de recursos didáticos, planejamento inadequado das atividades. A partir dessa constatação, procurou-se debater a impossibilidade de tratar do tema fora do trabalho interdisciplinar, bem como, e principalmente, a importância de um estudo mais aprofundado de EA, vinculando teoria e prática, tanto na formação docente, como em projetos escolares, a fim de fugir do tradicional vínculo “EA e ecologia, lixo e horta”.Facultad de Humanidades y Ciencias de la Educació

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    NUC041, a Prodrug of the DNA Methytransferase Inhibitor 5-aza-2′,2′-Difluorodeoxycytidine (NUC013), Leads to Tumor Regression in a Model of Non-Small Cell Lung Cancer

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    5-aza-2′,2′-difluorodeoxycytidine (NUC013) has been shown to be significantly safer and more effective than decitabine in xenograft models of human leukemia and colon cancer. However, it suffers from a similar short half-life as other DNA methyltransferase inhibitors with a 5-azacytosine base, which is problematic for nucleosides that primarily target tumor cells in S phase. Because of the relative instability of 5-azanucleosides, a prodrug approach was developed to improve the pharmacology of NUC013. NUC013 was conjugated with trimethylsilanol (TMS) at the 3′ and 5′ position of the sugar, rendering the molecule hydrophobic and producing 3′,5′-di-trimethylsilyl-2′,2′-difluoro-5-azadeoxycytidine (NUC041). NUC041 was designed to be formulated in a hydrophobic vehicle, protecting it from deamination and hydrolysis. In contact with blood, the TMS moieties are readily hydrolyzed to release NUC013. The half-life of NUC013 administered intravenously in mice is 20.1 min, while that of NUC013 derived from intramuscular NUC041 formulated in a pegylated-phospholipid depot is 3.4 h. In a NCI-H460 xenograft of non-small cell lung cancer, NUC013 was shown to significantly inhibit tumor growth and improve survival. Treatment with NUC041 also led to significant tumor growth inhibition. However, NUC041-treated mice had significantly more tumors ulcerate than either NUC013 treated mice or saline control mice, and such ulceration occurred at significantly lower tumor volumes. In these nude mice, tumor regression was likely mediated by the derepression of the tumor suppressor gene p53 and resultant activation of natural killer (NK) cells

    Patterns of West Nile Virus Infection in Ohio Blue Jays: Implications for Initiation of the Annual Cycle

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    West Nile virus (WNV) was first detected in North America in New York City in 1999 and rapidly moved westward. Understanding the mechanisms by which the amplification cycle is reinitiated each year increases our ability to predict epizootics and geographic expansion of the disease. Such understanding is enhanced by knowledge of the patterns of infection in the vertebrate reservoir hosts. Blue jays (Cyanocitta cristata) may serve as reservoir hosts for WNV. We examined the influence of age and date on the prevalence of WNV in jay carcasses in Ohio during May–August 2002. Percent of carcasses that were infected increased significantly with time from 3% in May to more than 90% by August. We found no difference in prevalence between juvenile (nestlings and fledglings) and adult jays early in the season, which contradicts the expected pattern if the majority of the adults sampled in 2002 had been exposed to the virus in 2001. Therefore, jays infected in 2001 were unlikely to have been important in initiating the 2002 virus cycle in Ohio

    Pathogenesis of a Genogroup II Human Norovirus in Gnotobiotic Pigs

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    We evaluated the gnotobiotic (Gn) pig as a model to study the pathogenesis of human norovirus (HuNoV) and to determine the target cells for viral replication. Sixty-five Gn pigs were inoculated with fecal filtrates of the NoV/GII/4/HS66/2001/US strain or with pig-passaged intestinal contents (IC) and euthanized acutely (n = 43) or after convalescence (n = 22). Age-matched Gn piglets (n = 14) served as mock-inoculated controls. Seventy-four percent (48/65) of the inoculated animals developed mild diarrhea compared to 0 of 14 controls. Pigs from postinoculation days (PID) 1 to 4 tested positive for HuNoV by reverse transcription-PCR of rectal swab fluids (29/65) and IC (9/43) and by antigen (Ag) enzyme-linked immunosorbent assay (ELISA) using antiserum to virus-like particles of HuNoV GII/4. No control pigs were positive. Histopathologic examination showed mild lesions in the proximal small intestine of only one pig (1/7). Seroconversion after PID 21 was detected by antibody ELISA in 13 of 22 virus-inoculated pigs (titers, 1:20 to 1:200) but not in controls. Immunofluorescent microscopy using a monoclonal antibody to HuNoV GII capsid revealed patchy infection of duodenal and jejunal enterocytes of 18 of 31 HuNoV-inoculated pigs with a few stained cells in the ileum and no immunofluorescence (IF) in mock-inoculated controls. Immunofluorescent detection of the viral nonstructural N-terminal protein antigen in enterocytes confirmed translation. Transmission electron microscopy of intestines from HuNoV-inoculated pigs showed disrupted enterocytes, with cytoplasmic membrane vesicles containing calicivirus-like particles of 25 to 40 nm in diameter. In summary, serial passage of HuNoV in pigs, with occurrence of mild diarrhea and shedding, and immunofluorescent detection of the HuNoV structural and nonstructural proteins in enterocytes confirm HuNoV replication in Gn pigs

    Iodine Intakes of Victorian Schoolchildren Measured Using 24-h Urinary Iodine Excretion

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    Mandatory fortification of bread with iodized salt was introduced in Australia in 2009, and studies using spot urine collections conducted post fortification indicate that Australian schoolchildren are now replete. However an accurate estimate of daily iodine intake utilizing 24-h urinary iodine excretion (UIE μg/day) has not been reported and compared to the estimated average requirement (EAR). This study aimed to assess daily total iodine intake and status of a sample of primary schoolchildren using 24-h urine samples. Victorian primary school children provided 24-h urine samples between 2011 and 2013, from which urinary iodine concentration (UIC, μg/L) and total iodine excretion (UIE, μg/day) as an estimate of intake was determined. Valid 24-h urine samples were provided by 650 children, mean (SD) age 9.3 (1.8) years (n = 359 boys). The mean UIE of 4–8 and 9–13 year olds was 94 (48) and 111 (57) μg/24-h, respectively, with 29% and 26% having a UIE below the age-specific EAR. The median (IQR) UIC was 124 (83,172) μg/L, with 36% of participants having a UIC < 100 μg/L. This convenience sample of Victorian schoolchildren were found to be iodine replete, based on UIC and estimated iodine intakes derived from 24-h urine collections, confirming the findings of the Australian Health Survey

    Comparative pathology study of Venezuelan, eastern, and western equine encephalitis viruses in non-human primates

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    Venezuelan, eastern, and western equine encephalitis viruses (VEEV, EEEV, and WEEV) are mosquito-borne viruses in the Americas that cause central nervous system (CNS) disease in humans and equids. In this study, we directly characterized the pathogenesis of VEEV, EEEV, and WEEV in cynomolgus macaques following subcutaneous exposure because this route more closely mimics natural infection via mosquito transmission or by an accidental needle stick. Our results highlight how EEEV is significantly more pathogenic compared to VEEV similarly to what is observed in humans. Interestingly, EEEV appears to be just as neuropathogenic by subcutaneous exposure as it was in previously completed aerosol exposure studies. In contrast, subcutaneous exposure of cynomolgus macaques with WEEV caused limited disease and is contradictory to what has been reported for aerosol exposure. Several differences in viremia, hematology, or tissue tropism were noted when animals were exposed subcutaneously compared to prior aerosol exposure studies. This study provides a more complete picture of the pathogenesis of the encephalitic alphaviruses and highlights how further defining the neuropathology of these viruses could have important implications for the development of medical countermeasures for the neurovirulent alphaviruses
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