962 resultados para Oncogenic viruses


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A continuous cell line (SISK) from kidney of sea bass, Lates calcarifer, has been established and characterized. The cell line was maintained in Leibovitz' L-15 supplemented with 15% fetal bovine serum. This cell line has been subcultured more than 100 times over a period of 2 years. The SISK cell line consists of predominantly of epithelial-like cells. These cells showed strong positive for epithelial markers such as cytokeratin 19 and pancytokeratin. The cells were able to grow at temperature between 25 and 32 °C with optimum temperature of 28 °C. The growth rate of sea bass kidney cells increased as the FBS proportion increased from 2% to 20% at 28 °C with optimum growth at the concentrations of 15% or 20% FBS. The distribution of chromosome number was 30 to 56 with a modal peak at 48 chromosomes. Polymerase chain reaction products were obtained from SISK cells and tissues of sea bass with primer sets of microsatellite markers of sea bass. Five fish viruses were tested on this cell line to determine its susceptibility to these viruses and this was found to be susceptible to MABV NC1 and nodavirus, and the infection was confirmed by RT-PCR and CPE. This suggests that the SISK cell line has good potential for the isolation of various fish viruses. This cell line has been shown to be susceptible to bacterial extracellular products. The SISK cell line is the India's first marine fish cell line.

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Lack of a valid shrimp cell line has been hampering the progress of research on shrimp viruses. One of the reasons identified was the absence of an appropriate medium which would satisfy the requirements of the cells in vitro. We report the first attempt to formulate an exclusive shrimp cell culture medium (SCCM) based on the haemolymph components of Penaeus monodon prepared in isosmotic seawater having 27 % salinity. The SCCM is composed of 22 amino acids, 4 sugars, 6 vitamins, cholesterol, FBS, phenol red, three antibiotics, potassium dihydrogen phosphate and di-sodium hydrogen phosphate at pH 6.8–7.2. Osmolality was adjusted to 720 ± 10 mOsm kg-1 and temperature of incubation was 25 8C. The most appropriate composition was finally selected based on the extent of attachment of cells and their proliferation by visual observation. Metabolic activity of cultured cells was measured by MTT assay and compared with that in L-15 (29), modified L-15 and Grace’s insect medium, and found better performance in SCCM especially for lymphoid cells with 107 % increase in activity and 85 ± 9 days of longevity. The cells from ovary and lymphoid organs were passaged twice using the newly designed shrimp cell dissociation ‘‘cocktail’’.

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Hepcidin is cysteine-rich short peptide of innate immune system of fishes, equipped to perform prevention and proliferation of invading pathogens like bacteria and viruses by limiting iron availability and activating intracellular cascades. Hepcidins are diverse in teleost fishes, due to the varied aquatic environments including exposure to pathogens, oxygenation and iron concentration. In the present study, we report a 87-amino acid (aa) preprohepcidin (Hepc-CB1) with a signal peptide of 24 aa, a prodomain of 39 aa and a bioactive mature peptide of 24 aa from the gill mRNA transcripts of the deep-sea fish spinyjaw greeneye, Chlorophthalmus bicornis. Molecular characterisation and phylogenetic analysis categorised the peptide to HAMP2-like group with a mature peptide of 2.53 kDa; a net positive charge (?3) and capacity to form b-hairpin-like structure configured by 8 conserved cysteines. The present work provides new insight into the mass gene duplication events and adaptive evolution of hepcidin isoforms with respect to environmental influences and positive Darwinian selection. This work reports a novel hepcidin isoform under the group HAMP2 from a nonacanthopterygian deep-sea fish, C. bicornis

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There are a number of genes involved in the regulation of functional process in marine bivalves. In the case of pearl oyster, some of these genes have major role in the immune/defence function and biomineralization process involved in the pearl formation in them. As secondary filter feeders, pearl oysters are exposed to various kinds of stressors like bacteria, viruses, pesticides, industrial wastes, toxic metals and petroleum derivatives, making susceptible to diseases. Environmental changes and ambient stress also affect non-specific immunity, making the organisms vulnerable to infections. These stressors can trigger various cellular responses in the animals in their efforts to counteract the ill effects of the stress on them. These include the expression of defence related genes which encode factors such as antioxidant genes, pattern recognition receptor proteins etc. One of the strategies to combat these problems is to get insight into the disease resistance genes, and use them for disease control and health management. Similarly, although it is known that formation of pearl in molluscs is mediated by specialized proteins which are in turn regulated by specific genes encoding them, there is a paucity of sufficient information on these genes.In view of the above facts, studies on the defence related and pearl forming genes of the pearl oyster assumes importance from the point of view of both sustainable fishery management and aquaculture. At present, there is total lack of sufficient knowledge on the functional genes and their expressions in the Indian pearl oyster Pinctada fucata. Hence this work was taken up to identify and characterize the defence related and pearl forming genes, and study their expression through molecular means, in the Indian pearl oyster Pinctada fucata which are economically important for aquaculture at the southeast coast of India. The present study has successfully carried out the molecular identification, characterization and expression analysis of defence related antioxidant enzyme genes and pattern recognition proteins genes which play vital role in the defence against biotic and abiotic stressors. Antioxidant enzyme genes viz., Cu/Zn superoxide dismutase (Cu/Zn SOD), glutathione peroxidise (GPX) and glutathione-S-transferase (GST) were studied. Concerted approaches using the various molecular tools like polymerase chain reaction (PCR), random amplification of cDNA ends (RACE), molecular cloning and sequencing have resulted in the identification and characterization of full length sequences (924 bp) of the Cu/Zn SOD, most important antioxidant enzyme gene. BLAST search in NCBI confirmed the identity of the gene as Cu/Zn SOD. The presence of the characteristic amino acid sequences such as copper/zinc binding residues, family signature sequences and signal peptides were found out. Multiple sequence alignment comparison and phylogenetic analysis of the nucleotide and amino acid sequences using bioinformatics tools like BioEdit,MEGA etc revealed that the sequences were found to contain regions of diversity as well as homogeneity. Close evolutionary relationship between P. fucata and other aquatic invertebrates was revealed from the phylogenetic tree constructed using SOD amino acid sequence of P. fucata and other invertebrates as well as vertebrates

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With this document, we provide a compilation of in-depth discussions on some of the most current security issues in distributed systems. The six contributions have been collected and presented at the 1st Kassel Student Workshop on Security in Distributed Systems (KaSWoSDS’08). We are pleased to present a collection of papers not only shedding light on the theoretical aspects of their topics, but also being accompanied with elaborate practical examples. In Chapter 1, Stephan Opfer discusses Viruses, one of the oldest threats to system security. For years there has been an arms race between virus producers and anti-virus software providers, with no end in sight. Stefan Triller demonstrates how malicious code can be injected in a target process using a buffer overflow in Chapter 2. Websites usually store their data and user information in data bases. Like buffer overflows, the possibilities of performing SQL injection attacks targeting such data bases are left open by unwary programmers. Stephan Scheuermann gives us a deeper insight into the mechanisms behind such attacks in Chapter 3. Cross-site scripting (XSS) is a method to insert malicious code into websites viewed by other users. Michael Blumenstein explains this issue in Chapter 4. Code can be injected in other websites via XSS attacks in order to spy out data of internet users, spoofing subsumes all methods that directly involve taking on a false identity. In Chapter 5, Till Amma shows us different ways how this can be done and how it is prevented. Last but not least, cryptographic methods are used to encode confidential data in a way that even if it got in the wrong hands, the culprits cannot decode it. Over the centuries, many different ciphers have been developed, applied, and finally broken. Ilhan Glogic sketches this history in Chapter 6.

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Dictyostelium discoideum is a social amoeba that serves as a model system for RNA interference and related mechanisms. Its position between plants and animals enables evolutionary snapshot of mechanisms and protein machinery involved in investigated subjects. MiRNAs are small regulatory RNAs that are evolutionary conserved and present in animals, plants, viruses and some prokaryotes. They have roles in development, cell growth and differentiation, apoptosis and their miss-regulation is associated with many diseases such as cancer, neurodegenerative disorders and diabetes. Recently, through sequencing of DNA libraries miRNAs have been discovered in D. discoideum. In this work, it has been shown that heterologues miRNA let-7 can be expressed and processed in D. discoideum. Expression of let-7 miRNA in social amoeba resulted in a strong developmental phenotype suggesting an overload of the processing/silencing system or/and endogenous targets. The various effects on prel-7 strain have been observed and characterized, serving as a background for postulation of miRNA roles. An artificial miRNA system has been established and imposed to D. discoideum, showing that miRNAs in Dictyostelium could mediate gene expression on the level of mRNA stability and on the posttranscriptional level. Furthermore, presence of translational inhibition as a type of gene control was shown for the first time in this organism. Due to it new structures representing co-localities of miRNA and target mRNA have been detected. Taken together, this work shows functional artificial miRNA system and postulates roles of endogenous small RNA in social amoeba.

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Intrinsic resistance to the epidermal growth factor receptor (EGFR; HER1) tyrosine kinase inhibitor (TKI) gefitinib, and more generally to EGFR TKIs, is a common phenomenon in breast cancer. The availability of molecular criteria for predicting sensitivity to EGFR-TKIs is, therefore, the most relevant issue for their correct use and for planning future research. Though it appears that in non-small-cell lung cancer (NSCLC) response to gefitinib is directly related to the occurrence of specific mutations in the EGFR TK domain, breast cancer patients cannot be selected for treatment with gefitinib on the same basis as such EGFR mutations have been reported neither in primary breast carcinomas nor in several breast cancer cell lines. Alternatively, there is a general agreement on the hypothesis that the occurrence of molecular alterations that activate transduction pathways downstream of EGFR (i.e., MEK1/MEK2 - ERK1/2 MAPK and PI-3'K - AKT growth/survival signaling cascades) significantly affect the response to EGFR TKIs in breast carcinomas. However, there are no studies so far addressing a role of EGF-related ligands as intrinsic breast cancer cell modulators of EGFR TKI efficacy. We recently monitored gene expression profiles and sub-cellular localization of HER-1/-2/-3/-4 related ligands (i.e., EGF, amphiregulin, transforming growth factor-α, ß-cellulin, epiregulin and neuregulins) prior to and after gefitinib treatment in a panel of human breast cancer cell lines. First, gefitinibinduced changes in the endogenous levels of EGF-related ligands correlated with the natural degree of breast cancer cell sensitivity to gefitinib. While breast cancer cells intrinsically resistant to gefitinib (IC50 ≥15 μM) markedly up-regulated (up to 600 times) the expression of genes codifying for HERspecific ligands, a significant down-regulation (up to 106 times) of HER ligand gene transcription was found in breast cancer cells intrinsically sensitive to gefitinib (IC50 ≤1 μM). Second, loss of HER1 function differentially regulated the nuclear trafficking of HER-related ligands. While gefitinib treatment induced an active import and nuclear accumulation of the HER ligand NRG in intrinsically gefitinib-resistant breast cancer cells, an active export and nuclear loss of NRG was observed in intrinsically gefitinib-sensitive breast cancer cells. In summary, through in vitro and pharmacodynamic studies we have learned that, besides mutations in the HER1 gene, oncogenic changes downstream of HER1 are the key players regulating gefitinib efficacy in breast cancer cells. It now appears that pharmacological inhibition of HER1 function also leads to striking changes in both the gene expression and the nucleo-cytoplasmic trafficking of HER-specific ligands, and that this response correlates with the intrinsic degree of breast cancer sensitivity to the EGFR TKI gefitinib. The relevance of this previously unrecognized intracrine feedback to gefitinib warrants further studies as cancer cells could bypass the antiproliferative effects of HER1-targeted therapeutics without a need for the overexpression and/or activation of other HER family members and/or the activation of HER-driven downstream signaling cascades

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This is the INFO2009 project for group 17 Our topic is Security. Our resource is a website that contains links to different questionnaires we created to help educate people in various subtopics of Security

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La EPOC es una causa importante de morbilidad y mortalidad en el mundo y su prevalencia en Bogotá alcanza hasta 8,5%. Las exacerbaciones están asociadas a deterioro funcional y de la calidad de vida por lo que se consideran un factor cardinal de la enfermedad. En la literatura se ha descrito que las infecciones por bacterias y/o virus son las responsables del 78% de las exacerbaciones. Estos datos han sido descritos en poblaciones diferentes y no hay datos en la literatura que muestren cual es la epidemiología local de las exacerbaciones de EPOC y menos aún de aquellas que se asocian a consolidaciones neumónicas. Objetivo: Comparar la microbiología de las exacerbaciones severas de la EPOC que requieren ingreso a UCI con y sin infiltrados alveolares. Materiales y métodos: Estudio de corte transversal en el que se estudiaron pacientes con EPOC que ingresaron a la UCI Médica de la FCI-IC por exacerbación severa, asociada o no a infiltrados alveolares. Se tomaron muestras de microbiología, serológicas y radiografía de tórax para evaluar la etiología de la exacerbación, si se asocia a coinfección viral y a consolidación neumónica o no. Resultados: No se encontró una diferencia estadísticamente significativa en la microbiología de los diferentes grupos evaluados. Se encontró un resistencia global del 24% y llama la atención que hay una alta prevalencia de Serratia Marcescens AMPc entre los 2 grupos, germen que no está descrito como patógeno común en la literatura. Se encontraron diferencias en cuanto a factores de riesgo para presentar neumonía asociada como lo son un mayor índice de paquetes/año (55.1.6 vs. 36.3 paq/año, sig.=0.021). Así mismo se demostró que los pacientes con neumonía asociada presentan mayor necesidad de IOT (48.9 vs. 23.9, sig.=0.013). No hay diferencia significativa en desenlaces como mortalidad (20.5 vs. 13.0, sig.=0.346). Conclusiones: A pesar de no haber diferencia microbiológica entre los 2 grupos se encontraron variables como factores de riesgo y variables clínicas que pueden ayudar a proponer planes de manejo en los dos escenarios. El hecho de encontrar un paciente con neumonía asociada al cuadro de exacerbación no debe afectar en la toma de decisiones en relación al tratamiento antibiótico.

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Infections are believed to contribute to the maturation of the immune system from the innate to the adaptive phases and therefore may take part in the induction of autoimmune conditions. In the current study, we present an extensive analysis conducted on sera samples of patients with rheumatoid arthritis in order to seek evidence of previous or coexisting infectious processes using the Bio-Rad BioPlex immunoassay analyzer. We detected higher rates of serological evidence of infections with Epstein–Barr virus and cytomegalovirus viruses. Our findings may indicate a role of these viruses in the pathogenesis of RA.

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Introducción. Con la creación de la vacuna contra el virus de papiloma humano en los años ochentas, se ha promovido su aplicación de manera sistemática para evitar el cáncer cervical, que es la segunda causa de mortalidad por cáncer en mujeres en edad fértil. Actualmente se desconoce el impacto de los resultados de su aplicación. Se pretendió evaluar la mejor evidencia relacionada con los resultados de la vacuna contra VPH en mujeres en edad fértil. Metodología Se realizó una revisión sistemática de literatura incluyendo los artículos con mejor evidencia en los últimos cinco años. Los términos mesH incluyeron HPV vaccine, women, efficacy entre otros. Todos los artículos fueron clasificados por evidencia antes de ser analizados. Resultados Se encontraron un total de 557 artículos relacionados con el tema de los cuales 21 cumplieron criterios para su selección. La mayoría de artículos fueron clasificados como evidencia II. Las causas más frecuentes de exclusión fueron por tema no acorde y título. Discusión Los resultados de la revisión sistemática permiten definir que la eficacia de la vacuna contra VPH, tanto y la vacuna bivalente como y la cuadrivalente supera el 97% cuando se completan tres dosis. No hay reportes de eventos adversos graves, la edad de aplicación ideal es entre 9-14 años de edad.

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La influenza es una entidad clínica, que es causada por los virus de la influenza A, B y C del género Influenza. El virus de la influenza A se clasifica en subtipos, con base en 2 antígenos de superficie: la hemaglutinina y la neuraminidasa. La respuesta inmune frente a estos antígenos (especialmente frente a la hemaglutinina), disminuye la probabilidad de infección, así como la severidad del cuadro clínico. La intención de este trabajo es describir el funcionamiento del programa de vigilancia centinela de influenza y otros virus respiratorios en Colombia, que permite identificar en que medida se alcanza la finalidad de esta actividad y que dificultades en general afectan su funcionamiento.

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La presente investigación tiene como objetivo analizar la incidencia de las agresiones cibernéticas en el desarrollo informático de las Fuerzas Armadas de Estados Unidos. Los diferentes estudios que se han realizado sobre el ciberespacio se han enfocado en el papel del individuo como actor principal y se ha dejado de lado las repercusiones que éste ha tenido para el Estado, como un nuevo eje de amenazas. Teniendo en cuenta lo anterior, esta investigación demostrará a partir del concepto de securitización, que se busca priorizar la “ciberseguridad” dentro de la agenda del gobierno estadounidense. Al ser este un estudio que aborda experiencias concretas durante un periodo de tiempo de más de 10 años, el diseño metodológico de la investigación será longitudinal, ya que abarcará estudios, artículos, textos y resoluciones que se han realizado desde 2003 hasta la actualidad.

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Introducción: La infección por un tipo de Virus del Papiloma Humano de alto riesgo (VPH-AR), es el factor principal en el desarrollo de Cáncer de Cérvix (CC). La carga viral puede modular esta asociación, por lo que resulta importante su cuantificación y el establecimiento de su relación con lesiones precursoras de CC. Metodología: 60 mujeres con lesiones escamosas intraepiteliales (LEI) y 120 mujeres sin LEI, confirmadas por colposcopia, fueron incluidas en el estudio. Se determinó la carga viral de 6 tipos de VPH-AR, mediante PCR en tiempo real. Se estimaron OR crudos y ajustados para evaluar la asociación entre la carga viral de cada tipo y las lesiones cervicales. Resultados: 93.22% de mujeres con LEI y 91.23% de mujeres negativas, fueron positivas para al menos un tipo de VPH. VPH-18 y VPH-16 fueron los tipos más prevalentes, junto con VPH-31 en mujeres sin LEI. No se encontraron diferencias estadísticamente significativas de las cargas virales entre éstos dos grupos, aunque se observó un mayor carga viral en lesiones para algunos tipos virales. Una mayor frecuencia de lesiones se asoció a infecciones con carga baja de VPH-16 (ORa: 3.53; IC95%: 1.16 – 10.74), en comparación a mujeres con carga alta de VPH-16, (ORa: 2.63; IC95%: 1.09 – 6.36). En infecciones por VPH-31, la presencia de carga viral alta, se asoció con una menor frecuencia de lesiones (ORa: 0.34; IC95%: 0.15 – 0.78). Conclusiones: La prevalencia tipo-específica de VPH se corresponde con las reportadas a nivel mundial. La asociación entre la carga viral del VPH y la frecuencia de LEI es tipo específica y podría depender de la duración de la infección, altas cargas relacionadas con infecciones transitorias, y bajas cargas con persistentes. Este trabajo contribuye al entendimiento del efecto de la carga viral en la historia natural del CC; sin embargo, estudios prospectivos son necesarios para confirmar estos resultados.

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Introducción: Todos los trabajadores del área de la salud están en riesgo de padecer un accidente biológico. No obstante los estudiantes de estas aéreas, pueden presentar más riesgo porque apenas están en formación y no tienen la práctica o experiencia suficiente. Existen varios artículos que han estudiado la incidencia y prevalencia de accidentes biológicos en los trabajadores del área de la salud, Sin embargo, sobre esta problemática de la población estudiantil del área de la salud, se encuentra menos literatura. Por lo tanto con esta revisión sistemática se busca analizar y actualizar este tema. Métodos: Se realizó una revisión de la literatura científica de artículos publicados en los últimos 14 años, en relación con la prevalencia de accidentes biológicos en estudiantes de medicina, odontología, enfermería y residentes del área de la salud a nivel mundial. Se llevó a cabo la búsqueda en la base de datos de Pubmed, encontrando un total de 100 artículos, escritos en inglés, francés, español o portugués. Resultados: Las prevalencias encontradas sobre accidentes biológicos en estudiantes fueron las siguientes: en países europeos a nivel de enfermería los valores oscilan entre 10.2 % a 32%, en medicina fueron del 16%-58.8%, y en odontología del 21 %. En países asiáticos, se encontró que en enfermería el porcentaje varía de 49%-96 %, en medicina van del 35% -68%, y en odontología varia de 68.a 75.4%. En Norte América, en medicina las cifras fluctúan alrededor del 11-72.7 % y en odontología giran alrededor del 19.1%. Finalmente respecto a Suramérica la prevalencia fue de 31.2 a 46.7% en medicina, y del 40% en enfermería. Conclusiones: Por lo anterior se pudo concluir que, la prevalencia de accidentes biológicos en los estudiantes del área de la salud es elevada y varía según el continente en el que se encuentren.