Spontaneous virus reactivation in cattle chronically infected with bovine leukemia virus

Background: The absence of virus expression during the chronic stage of bovine leukemia virus (BLV) infection and its reactivation upon ex vivo culture has become a long-lived Dogma. During the chronic stage of BLV infection the immune response limits viral replication and the mitotic division of latently infected cells, carrying BLV provirus, allows viral expansion and disease progression towards a lymphoproliferative disorder. Several stressor factors have been associated with animal production and handling. As natural mediator of stress, glucocorticoids are strong immunosuppressive agents; moreover, they can bind long-terminal repeat region of retroviruses and induce viral expression. In the present study, we present a case report describing the spontaneous reactivation of BLV infection in naturally infected cattle. Case presentation: In order to investigate if virus reactivation occurred in vivo during the course of BLV infection, we followed up for 328 days one Holstein cow (> 3 years) chronically infected with BLV which presented high-proviral loads. This animal was neither lactating nor pregnant. Furthermore, we investigated if a stressor stimulus, in this case the administration of a synthetic glucocorticoid (dexamethasone), could impact the course of BLV infection in three additional cattle. For the first time, we observed a high level of BLV transcripts in a total of four cattle chronically infected with BLV. The detection of viral transcripts corresponding to pol gene strongly suggests virus reactivation in these animals. Interestingly, this simultaneous virus reactivation was unrelated to dexamethasone treatment. Conclusions: We reported for the first time spontaneous and high level of BLV transcriptional activation in cattle chronically infected with BLV. Although virus reactivation was unrelated to dexamethasone treatment, other stressor stimuli might have influenced this outcome. Future studies will be necessary to understand these observations, since the spontaneous virus reactivation presented here might have implications on BLV pathogenesis and transmission.Instituto de VirologíaFil: Jaworski, Juan Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Petersen, Marcos Iván. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Carignano, Hugo. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Trono, Karina Gabriela. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; Argentin

Quantification of bovine leukemia virus proviral DNA using a low-cost real-time polymerase chain reaction

The detection of bovine leukemia virus (BLV) proviral DNA is an important tool to address whether an animal is infected with BLV. Compared with serological assays, real-time PCR accounts for greater sensitivity and can serve as a confirmatory test for the clarification of inconclusive or discordant serological test results. However, the high cost related to real-time PCR assays has limited their systematic inclusion in BLV surveillance and eradication programs. The aim of the present study was to validate a low-cost quantitative real-time PCR. Interestingly, by using SYBR Green detection dye, we were able to reduce the cost of a single reaction by a factor of 5 compared with most common assays based on the use of fluorogenic probes (i.e., TaqMan technology). This approach allowed a highly sensitive and specific detection and quantification of BLV proviral DNA from purified peripheral blood leukocytes and a milk matrix. Due to its simplicity and low cost, our in-house BLV SYBR quantitative real-time PCR might be used either as a screening or as a confirmatory test in BLV control programs.Fil: Petersen Cruceño, Marcos Iván. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alvarez, Irene. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Trono, Karina Gabriela. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jaworski, Juan Pablo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

BLOGS ESCOLARES SOBRE SEXUALIDADE: ESTUDO EXPLORATÓRIO DOCUMENTAL

O objetivo foi analisar a estrutura e a utilização do blog escolar por adolescentes, ao abordarem a temática da sexualidade. Trata-se de pesquisa quantitativa exploratória documental, realizada com 11 blogs criados por estudantes que estavam disponíveis online em março de 2012. As informações foram submetidas à análise hipertextual e daestatística descritiva, observando-se os preceitos éticos em pesquisa. Os blogs grupais e educacionais desenvolvidos em escolas portuguesas e brasileiras eram na maioria assinados pelos autores e sofreram poucas atualizações. As publicações escritas mesclaram linguagem científica com informal, apresentavam vídeos e imagens. Informações sobre a quantidade de seguidores, acessos, comentários e contato para dúvidas não foram encontrados na totalidade dos blogs. Entre os assuntos discutidos, destacaram-se métodos contraceptivos e doenças sexualmente transmissíveis (DSTs). Os blogs são recurso de educação em saúde que necessitam assumir o seu espaço de discussão ativa e podemcontar com a participação de profissionais da saúde

Overexpression Of Muts Alpha Complex Proteins Predicts Poor Prognosis In Oral Squamous Cell Carcinoma

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The DNA mismatch repair (MMR) system is responsible for the detection and correction of errors created during DNA replication, thereby avoiding the incorporation of mutations in dividing cells. The prognostic value of alterations in MMR system has not previously been analyzed in oral squamous cell carcinoma (OSCC). The study comprised 115 cases of OSCC diagnosed between 1996 and 2010. The specimens collected were constructed into tissue microarray blocks. Immunohistochemical staining for MutS alpha complex proteins hMSH2 and hMSH6 was performed. The slides were subsequently scanned into high-resolution images, and nuclear staining of hMSH2 and hMSH6 was analyzed using the Nuclear V9 algorithm. Univariable and multivariable Cox proportional hazard regression models were performed to evaluate the prognostic value of hMSH2 and hMSH6 in OSCC. All cases in the present cohort were positive for hMSH2 and hMSH6 and a direct correlation was found between the expression of the proteins (P<0.05). The mean number of positive cells for hMSH2 and hMSH6 was 64.44 +/- 15.21 and 31.46 +/- 22.38, respectively. These values were used as cutoff points to determine high protein expression. Cases with high expression of both proteins simultaneously were classified as having high MutS alpha complex expression. In the multivariable analysis, high expression of the MutS alpha complex was an independent prognostic factor for poor overall survival (hazard ratio: 2.75, P = 0.02). This study provides a first insight of the prognostic value of alterations in MMR system in OSCC. We found that MutS alpha complex may constitute a molecular marker for the poor prognosis of OSCC.9522Brazilian National Council for Scientific and Technological Development (CNPq)Postgraduate Research Group of the Porto Alegre University Hospital [GPPG/FIPE: 15-0210]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Webquest y blog como estrategias educativas en salud escolar

Objetivo: Descrever ação de educação em saúde sobre alimentação saudável utilizando como estratégia o webquest e o blog com estudantes do ensino fundamental de uma escola pública.Método: Relato da atividade de educação em saúde realizada em 2014 com quatorze estudantes do 8º ano de escola pública. O "Blog da Alimentação Saudável" foi desenvolvido pelos estudantes utilizando a metodologia da webquest orientados pela enfermeira durante quatro períodos da disciplina de ciências.Resultados: Em três grupos de trabalho os estudantes realizaram o webquest disponibilizado em site com as etapas introdução, tarefa, processos e recursos. O blog foi elaborado em site gratuito em resposta às questões do webquest. A avaliação dos estudantes destacou os aspectos positivos, as dificuldades e as recomendações para futuras atividades.Conclusão: Essa tecnologia torna a busca pelo conhecimento participativa e ativa, além de ser um espaço de integração dos profis-sionais da saúde no ambiente escolar.Objective: To describe health education strategy on healthy eating using webquest and blog with elementary school students from a public school.Method: Report the health education activity carried out in 2014 with fourteen students from the 8th year of public school. The "Healthy Eating Blog" was developed by the students using the webquest methodology guided by the nurse during four periods of the science discipline.Results: In three work groups the students performed the webquest made available on site with the introduction, task, process and resource stages. The blog was written in a free website in response to WebQuest questions. The students’ evaluation highlighted the positives, difficulties and recommendations for future activities.Conclusion: This technology makes the search for participatory and active knowledge, besides being a space for integration of health professionals in the school environment.Objetivo: Describir la acción de educación en salud en la alimentación saludable mediante una estrategia de búsqueda en la red y el blog con los estudiantes de primaria en una escuela pública.Método: Actividades de educación en salud realizado en 2014 con catorce estudiantes de la escuela pública de 8º grado. La "Alimen-tación saludable Blog" fue desarrollado por los estudiantes utilizando la metodología de la webquest guiada por la enfermera durante cuatro períodos de la disciplina de la ciencia.Resultados: En los tres grupos de trabajo que los estudiantes llevan a cabo la búsqueda en la red disponible en el sitio con los pasos de introducción, tareas, procesos y recursos. El blog se preparó de sitio web gratuito en respuesta a preguntas webquest. La evaluación de los estudiantes destacó los aspectos positivos, dificultades y recomendaciones para las actividades futuras.Conclusión: Esta tecnología hace que la búsqueda del conocimiento participativa y activa, además de ser uno de los espacios de integración profesionales de la salud en el entorno escolar

Webquest e blog como estratégias educativas em saúde escolar

Objetivo: Descrever ação de educação em saúde sobre alimentação saudável utilizando como estratégia o webquest e o blog com estudantes do ensino fundamental de uma escola pública.Método: Relato da atividade de educação em saúde realizada em 2014 com quatorze estudantes do 8º ano de escola pública. O “Blog da Alimentação Saudável” foi desenvolvido pelos estudantes utilizando a metodologia da webquest orientados pela enfermeira durante quatro períodos da disciplina de ciências.Resultados: Em três grupos de trabalho os estudantes realizaram o webquest disponibilizado em site com as etapas introdução, tarefa, processos e recursos. O blog foi elaborado em site gratuito em resposta às questões do webquest. A avaliação dos estudantes destacou os aspectos positivos, as dificuldades e as recomendações para futuras atividades.Conclusão: Essa tecnologia torna a busca pelo conhecimento participativa e ativa, além de ser um espaço de integração dos profissionais da saúde no ambiente escolar.Palavras-chave: Enfermagem. Blogging. Educação em saúde. Saúde escolar

Competence in Streptococcus pneumoniae and Close Commensal Relatives: Mechanisms and Implications

The mitis group of streptococci comprises species that are common colonizers of the naso-oral-pharyngeal tract of humans. Streptococcus pneumoniae and Streptococcus mitis are close relatives and share ~60–80% of orthologous genes, but still present striking differences in pathogenic potential toward the human host. S. mitis has long been recognized as a reservoir of antibiotic resistance genes for S. pneumoniae, as well as a source for capsule polysaccharide variation, leading to resistance and vaccine escape. Both species share the ability to become naturally competent, and in this context, competence-associated killing mechanisms such as fratricide are thought to play an important role in interspecies gene exchange. Here, we explore the general mechanism of natural genetic transformation in the two species and touch upon the fundamental clinical and evolutionary implications of sharing similar competence, fratricide mechanisms, and a large fraction of their genomic DNA

Surface Curvature Differentially Regulates Stem Cell Migration and Differentiation via Altered Attachment Morphology and Nuclear Deformation

Signals from the microenvironment around a cell are known to influence cell behavior. Material properties, such as biochemical composition and substrate stiffness, are today accepted as significant regulators of stem cell fate. The knowledge of how cell behavior is influenced by 3D geometric cues is, however, strongly limited despite its potential relevance for the understanding of tissue regenerative processes and the design of biomaterials. Here, the role of surface curvature on the migratory and differentiation behavior of human mesenchymal stem cells (hMSCs) has been investigated on 3D surfaces with well-defined geometric features produced by stereolithography. Time lapse microscopy reveals a significant increase of cell migration speed on concave spherical compared to convex spherical structures and flat surfaces resulting from an upward-lift of the cell body due to cytoskeletal forces. On convex surfaces, cytoskeletal forces lead to substantial nuclear deformation, increase lamin-A levels and promote osteogenic differentiation. The findings of this study demonstrate a so far missing link between 3D surface curvature and hMSC behavior. This will not only help to better understand the role of extracellular matrix architecture in health and disease but also give new insights in how 3D geometries can be used as a cell-instructive material parameter in the field of biomaterial-guided tissue regeneration.Peer reviewe

A biomaterial with a channel-like pore architecture induces endochondral healing of bone defects

Biomaterials developed to treat bone defects have classically focused on bone healing via direct, intramembranous ossification. In contrast, most bones in our body develop from a cartilage template via a second pathway called endochondral ossification. The unsolved clinical challenge to regenerate large bone defects has brought endochondral ossification into discussion as an alternative approach for bone healing. However, a biomaterial strategy for the regeneration of large bone defects via endochondral ossification is missing. Here we report on a biomaterial with a channel-like pore architecture to control cell recruitment and tissue patterning in the early phase of healing. In consequence of extracellular matrix alignment, CD146+ progenitor cell accumulation and restrained vascularization, a highly organized endochondral ossification process is induced in rats. Our findings demonstrate that a pure biomaterial approach has the potential to recapitulate a developmental bone growth process for bone healing. This might motivate future strategies for biomaterial-based tissue regeneration

Hidden Gems in the Transcriptome Maps of Competent Streptococci

Natural transformation is regarded as an important mechanism in bacteria that allows for adaptation to different environmental stressors by ensuring genome plasticity. Since the discovery of this phenomenon in Streptococcus pneumoniae, remarkable progress has been made in the understanding of the molecular mechanisms and pathways coordinating this process. Recently, the advent of high-throughput sequencing allows the posing of questions that address the system at a larger scale but also allow for the creation of high-resolution maps of transcription. Thus, while much is already known about genetic competence in streptococci, recent studies continue to reveal intricate novel regulation pathways and components. In this perspective article, we highlight the use of transcriptional profiling and mapping as a valuable resource in the identification and characterization of “hidden gems” pertinent to the natural transformation system. Such strategies have recently been employed in a variety of different species. In S. mutans, for example, genome editing combined with the power of promoter mapping and RNA-Seq allowed for the identification of a link between the ComCDE and the ComRS systems, a ComR positive feedback loop mediated by SigX, and the XrpA peptide, encoded within sigX, which inhibits competence. In S. pneumoniae, a novel member of the competence regulon termed BriC was found to be directly under control of ComE and to promote biofilm formation and nasopharyngeal colonization but not competence. Together these new technologies enable us to discover new links and to revisit old pathways in the compelling study of natural genetic transformation