964 resultados para Larvae survival rates


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Burkholderia phage AP3 (vB_BceM_AP3) is a temperate virus of the Myoviridae and the Peduovirinae subfamily (P2likevirus genus). This phage specifically infects multidrug-resistant clinical Burkholderia cenocepacia lineage IIIA strains commonly isolated from cystic fibrosis patients. AP3 exhibits high pairwise nucleotide identity (61.7%) to Burkholderia phage KS5, specific to the same B. cenocepacia host, and has 46.7% - 49.5% identity to phages infecting other species of Burkholderia. The lysis cassette of these related phages has a similar organization (putative antiholin, putative holin, endolysin and spanins) and shows 29-98% homology between specific lysis genes, in contrast to Enterobacteria phage P2, the hallmark phage of this genus. The AP3 and KS5 lysis genes have conserved locations and high amino acid sequence similarity. The AP3 bacteriophage particles remain infective up to 5 h at pH 4-10 and are stable at 60°C for 30 min, but are sensitive to chloroform, with no remaining infective particles after 24 h of treatment. AP3 lysogeny can occur by stable genomic integration and by pseudo-lysogeny. The lysogenic bacterial mutants did not exhibit any significant changes in virulence compared to wild-type host strain when tested in the Galleria mellonella moth wax model. Moreover, AP3 treatment of larvae infected with B. cenocepacia revealed a significant increase (P < 0.0001) in larvae survival in comparison to AP3-untreated infected larvae. AP3 showed robust lytic activity, as evidenced by its broad host range, the absence of increased virulence in lysogenic isolates, the lack of bacterial gene disruption conditioned by bacterial tRNA downstream integration site, and the absence of detected toxin sequences. These data suggest the AP3 phage is a promising potent agent against bacteria belonging to most common B. cenocepacia IIIA lineage strains.

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Thesis (Ph.D.)--University of Washington, 2016-08

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O cancro é um dos maiores causadores globais de mortalidade e morbilidade, ocorrendo cerca de 14 milhões de novos casos por ano e 8,2 milhões de mortes anuais com esta patologia, números que tendem a aumentar 70% nas próximas duas décadas. A característica tumoral mais nefasta é a sua capacidade de metastização para outros órgãos, um mecanismo que pode ser despoletado pela falha dos mecanismos normais de controlo de crescimento, proliferação e reparação celulares, que facilita o processo de transformação de células normais em células cancerígenas. A oncogénese processa-se em três etapas, a iniciação, a promoção e a progressão e pode ter origem em células estaminais cancerígenas, que regulam as capacidades de propagação e recidiva do tumor. As neoplasias hematológicas resultam de alterações genéticas e /ou epigenéticas que conduzem à desregulação da proliferação, ao bloqueio da diferenciação e/ou à resitência à apoptose. Para além dos fatores de risco exógenos, como agentes carcinogénicos físicos, químicos e biológicos, existem também fatores endógenos, incluindo características genéticas, que podem alterar a predisposição para o aparecimento de neoplasias, bem como influenciar a resposta à terapêutica. Uma das terapêuticas aplicadas no tratamento do cancro é a quimioterapia. Os fármacos administrados a doentes oncológicos seguem normalmente o percurso de absorção, distribuição, metabolização e eliminação. Este curso pode sofrer alterações caso as proteínas transportadoras e metabolizadoras necessárias não atuem corretamente. Para um melhor conhecimento da influência das alterações provocadas por variações nos genes que codificam proteínas transportadoras de efluxo (MDR1, MRP1), proteínas de influxo (OCTN2) e proteínas metabolizadoras (UCK2), o objetivo deste trabalho consistiu na avaliação de polimorfismos nos genes MDR1, MRP1, OCTN2 e UCK2 e da sua relação com a predisposição para o desenvolvimento de neoplasias hematológicas. Para isto, foram utilizadas amostras de 307 doentes com neoplasias hematológicas, 83 de Síndrome Mielodisplásica (SMD), 63 Leucemia Mieloide Aguda (LMA), 16 de Síndrome Mielodisplásica/Neoplasias Mieloproliferativas (SMD/NMP), 77 de Mieloma Múltiplo (MM) e 68 de Gamapatia Monoclonal de Significado Indeterminado (MGUS) e 164 de controlos não neoplásicos e/ou indivíduos saudáveis. As amostras de ADN foram extraídas do sangue periférico com protocolo adequado. De forma a determinar os genótipos correspondentes a cada amostra, realizaram-se técnicas de RFLP-PCR e ARMS-PCR. Posteriormente, calcularam-se estatisticamente as frequências alélicas e genotípicas relativas às variantes polimórficas dos genes MDR1, MRP1, OCTN2 e UCK2 e verificou-se se estavam em Equilíbrio de Hardy-Weinberg. De seguida, avaliou-se a força de associação entre as formas polimórficas e o risco de desenvolvimento de neoplasias hematológicas, através do cálculo do risco relativo por análise de regressão logística. Avaliaram-se ainda os perfis genéticos e a possível relação com o desenvolvimento e progressão da neoplasia com recurso a regressão logística e análise de Kaplan-Meier. De um modo geral as frequências alélicas e genotípicas não se revelaram alteradas comparativamente ao esperado. A análise do odds ratio associado ao polimorfismo rs1045642 do gene MDR1 revelou que o genótipo CT pode constituir um fator de risco aumentado de 1,84x para o desenvolvimento de Gamapatias Monoclonais e 2,27x para o desenvolvimento de Mieloma Múltiplo. Por outro lado, a presença de genótipos portadores do alelo T têm um efeito protetor no desenvolvimento de MM (OR=0,41). O cálculo do risco associado ao polimorfismo rs4148330 do gene MRP1 revela que o genótipo AG é um fator protetor (OR=0,50) para o desenvolvimento de LMA, assim como o alelo G (OR=0,50). Além disso, verificámos que existe uma associação de risco de desenvolver neoplasia com o polimorfismo rs2185268 do gene UCK2. De facto, a presença dos genótipos CC e AC representam um fator de risco 4,59x aumentado para o desenvolvimento de SMD/NMP. O polimorfismo rs274561 do gene OCTN2 não apresenta relação com o risco relativo de desenvolvimento neoplásico. Da avaliação da influência dos polimorfismos em estudo na sobrevivência global dos doentes, podemos assumir que a presença do genótipo GG relativo ao polimorfismo rs2185268 do gene UCK2 representa uma diminuição da sobrevivência em 11 meses. Os resultados obtidos a partir do nosso estudo permitem-nos concluir que os polimorfismos podem ser fatores relevantes na predisposição para o desenvolvimento de neoplasias hematológicas e na progressão destas doenças.

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Introdução: Uma adequada planificação é condição sine qua non para o êxito do tratamento com implantes. No entanto, nem sempre a colocação dos implantes na posição tridimensional ideal é, logo à partida, viável. Neste contexto, a correção dos colapsos da crista óssea com tecidos duros assume especial importância. Objetivos: O objetivo desta revisão narrativa é avaliar a eficácia dos diversos procedimentos existentes para aumento do rebordo com tecidos duros, de forma a facilitar a escolha do tratamento ideal. Materiais e Métodos: Pesquisou-se nas bases de dados MEDLINE, B-on e Google Académico. As palavras-chave utilizadas foram: “guided bone regeneration”, “ridge augmentation”, “seibert classification”, “alveolar bone splitting”, “horizontal bone augmentation” e “vertical bone augmentation”. Deu-se especial ênfase a revisões sistemáticas e meta-análises. A pesquisa foi limitada a artigos publicados em inglês, espanhol e em português até abril de 2016. Foram ainda consultados os livros “Tratado de Periodontia Clínica e Implantologia Oral” de Lindhe et al. (2005), “Implantes Dentais Contemporâneos” de Misch et al. (2009) e “Reabilitação com implantes endo-ósseos” de Alcoforado et al. (2008). Resultados: De um modo geral, todos os procedimentos analisados obtiveram altas taxas de sobrevivência aquando da reabilitação com implantes. No entanto, não houve diferenças significativas entre as diversas técnicas que possam levar a uma conclusão relevante sobre qual a melhor técnica a utilizar para este tipo de procedimento. Conclusão: Há evidências insuficientes para sugerir qual a técnica que deve ser preferida para o aumento de rebordo com tecidos duros, pelo que mais estudos são necessários.

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Intensification of aquaculture production in Uganda is likely to result into disease out-breaks leading to economic losses to commercial fish farms and associated natural aquatic ecosystems. This survey assessed health profiles of selected commercial fish farms and adjacent natural aquatic ecosystemsto identify fish diseases and parasites affecting Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus) in aquaculture systems in Uganda. Fish farms encounter disease out-breaks that cause low survival rates (0 - 30%), especially catfish hatcheries. Health management issues are not well understood by fish farmers, with some unable to detect diseased fish. Current control strategies to control aquatic pathogens include use of chemotherapeutants and antibiotics. Bacterial pathogens isolated included Flavobacterium columnare, Aeromonas sp., Edwardsiella sp., Psuedomonus sp., Steptococcus sp., Staphylococcus sp., Proteus sp., and Vibrio sp. A high occurrence of Flavobacterium columnare exists in both asymptomatic and symptomatic fish was observed. Parasites included protozoans (Ichthyopthirius multiphilis, Trichodina sp. and Icthyobodo sp.) and trematodes (Cleidodiscus sp. and Gyrodactylus sp.). Diagnosis and control of diseases and parasites in aquaculture production systems requires adoption of a regional comprehensive biosecurity strategy: the East African (EAC) region unto which this study directly contributes.

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Colorectal cancer (CRC) is the second most common cancer in Europe, with the second highest mortality rate. Although prognosis is improving, survival rates remain poor for those presenting with the most advanced stages of the disease. There is therefore a need for improved early diagnosis and thus a greater understanding of the early stages of the development of colorectal tumours is desirable. Additionally, as most deaths in colorectal cancer are due to advanced metastatic disease, it is of great interest to explore any potential mechanisms by which metastatic disease can be inhibited. N-WASP is a ubiquitously expressed protein with multiple intracellular roles including actin regulation and maintaining stability of epithelial cell-cell junctions. Through its role as an actin regulator, it has been implicated in the processes of invasion and metastasis of multiple cancer types. Its role in the development and progression of colorectal cancer however has not been fully explored. This thesis will present a series of in vitro and in vivo studies that were carried out with the aim of answering the following questions: • Does N-Wasp have a role in normal intestinal homeostasis? • Does N-Wasp knockout affect the development of tumours in a mouse model of intestinal tumourigenesis? • Does N-Wasp knockout affect the invasive properties of intestinal cancer in vitro? • Does N-WASP correlate with prognosis or other indicators in human colorectal cancer TMAs? Findings from the in vivo experiments, using an inducible, gut-specific knockout model, have uncovered potential roles for N-Wasp in regulating differentiation and migration of intestinal epithelial cells. Although it had no effect in short term models of intestinal hyperproliferation, N-Wasp knockout increased tumour burden and decreased survival in an established in vivo model of intestinal tumourigenesis, in which there is heterozygous loss of Apc (Apcfl/+). No effect was seen on tumour development or survival when additional N-WASP knockout was introduced into a more rapid model, with heterozygous loss of Apc and mutation of Kras (Apcfl/+ KrasG12D/+). N-WASP expression in human colorectal cancer was assessed using immunohistochemical staining of two tissue microarrays. Low levels of N-WASP expression were found to be associated with presence of MMR deficiency. There was no statistically significant difference in overall or cancer specific survival based on N-WASP expression. Collectively, the data presented here suggest a previously unreported role for N-WASP in regulation of intestinal epithelial differentiation and indicate that it may act as a tumour suppressor against development of benign precursor lesions of colorectal cancer. Further research is warranted to delineate the mechanisms underlying these processes.

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Objetivos: Analisar dados demográficos, apresentação clínica, fatores de risco, opções terapêuticas e sobrevida de doentes com adenocarcinoma nasossinusal. Material e Métodos: Estudo retrospetivo de doentes com Adenocarcinoma Nasossinusal tratados entre 2000 e 2014, no IPOFGL. Resultados: Identificamos 33 doentes com diagnóstico de Adenocarcinoma. A idade média foi de 65.6 anos. A terapêutica mais comum foi cirurgia com radioterapia adjuvante. A sobrevida global e livre de doença aos 3 anos foi de 57.6% e 40.5%. A invasão do seio esfenoidal (p=0.038) e da base do crânio (p=0.003) influenciaram a sobrevida global. O desenvolvimento de metástases à distância teve impacto sobre a sobrevida livre de doença (p=0.01). Conclusões: Os Adenocarcinomas são tumores raros. A excisão da lesão toma um papel determinante no tratamento dos doentes. Na nossa amostra, a invasão do seio esfenoidal, da base do crânio e o desenvolvimento de metástases à distância estão associados a um pior prognóstico.

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Kidney transplantation has been recognised as the optimal treatment choice for most end stage renal disease patients and the increase of allograft survival rates is achieved through the refinement of novel immunosuppressive agents. Chronic Graft Disease (CGD) is a multifactorial process that likely includes a combination of immunological, apoptotic and inflammatory factors. The application of individualised immunosuppressive therapies will also depend on the identification of risk factors that can influence chronic disease. Despite being the subject of several independent studies, investigations of the relationship between transforming growth factor-b1 (TGF-b1) polymorphisms and kidney graft outcome continue to be plagued by contradictory conclusions.

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Background: Non-small cell lung cancer (NSCLC) imposes a substantial burden on patients, health care systems and society due to increasing incidence and poor survival rates. In recent years, advances in the treatment of metastatic NSCLC have resulted from the introduction of targeted therapies. However, the application of these new agents increases treatment costs considerably. The objective of this article is to review the economic evidence of targeted therapies in metastatic NSCLC. Methods: A systematic literature review was conducted to identify cost-effectiveness (CE) as well as cost-utility studies. Medline, Embase, SciSearch, Cochrane, and 9 other databases were searched from 2000 through April 2013 (including update) for full-text publications. The quality of the studies was assessed via the validated Quality of Health Economic Studies (QHES) instrument. Results: Nineteen studies (including update) involving the MoAb bevacizumab and the Tyrosine-kinase inhibitors erlotinib and gefitinib met all inclusion criteria. The majority of studies analyzed the CE of first-line maintenance and second-line treatment with erlotinib. Five studies dealt with bevacizumab in first-line regimes. Gefitinib and pharmacogenomic profiling were each covered by only two studies. Furthermore, the available evidence was of only fair quality. Conclusion: First-line maintenance treatment with erlotinib compared to Best Supportive Care (BSC) can be considered cost-effective. In comparison to docetaxel, erlotinib is likely to be cost-effective in subsequent treatment regimens as well. The insights for bevacizumab are miscellaneous. There are findings that gefitinib is cost-effective in first- and second-line treatment, however, based on only two studies. The role of pharmacogenomic testing needs to be evaluated. Therefore, future research should improve the available evidence and consider pharmacogenomic profiling as specified by the European Medicines Agency. Upcoming agents like crizotinib and afatinib need to be analyzed as well. © Lange et al.

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International audience

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Background: We screened RARβ methylation in primary glioblastoma multiforme (GBM) and the results were evaluated based on the clinical data and treatment type. Objective: The objective of this study was to find new areas for the usage of MS-HRM applications in the determination of methylation levels in primary GBM samples and it shows the association of RARβ methylation with the clinical outcome. Methods: In our study, tumor samples were collected during surgical resection by the Department of Neurosurgery. The clinical and radiologic data was carefully reviewed, compared, and evaluated with the histological results. The methylation status of RARβ was determined by using MS-HRM. Results: RARβ gene methylation was detected in 24 out of 40 cases (60%), with different quantitative methylation levels. The mean survival time was 19 months form ethylated cases and 15 months for the non-methylated cases. The survival time of the patients who received treatment was 25 months and the survival time of the patients who received radiotherapy alone or where no treatment protocol applied was 15-20 months. Therefore, a significant difference in survival rates has been observed (P<0.05). This study indicates a potential prognostic value for GBM treatment planning. Conclusion: Our study is the first study to investigate RARβ methylation in primary GBMs. We conclude that the RARβ gene could be a new prognostic and predictive candidate marker to designate the treatment protocol for primary GBMs. Keywords:

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As the number of fungal pathogen outbreaks become more frequent worldwide across taxa, so have the number of species extirpations and communities persisting with the pathogen. This phenomenon raises questions, such as: “what leads to host extinction during an outbreak?” and “how are hosts persisting once the pathogen establishes?.” But the data on host populations and communities across life stages before and after pathogen arrival rarely exist to answer these questions. Over the past three to four decades, the amphibian-killing fungus Batrachochytrim dendrobatidis (Bd) spread in a wave-like manner across Central America, leading to rapid species extirpations and population declines. I collected data on tadpole and adult amphibians in El Copé, Panama before, during, and after the Bd outbreak to answer these questions. I used Bayesian statistical approaches to account for imperfect host and pathogen detection of marked and unmarked individuals. In the tadpole community, within 11 months of Bds arrival, density and occupancy rapidly declined. Species losses were phylogenetically correlated, with glass frogs disappearing first, and tree frogs and poison-dart frogs remaining. I found that tadpole communities resembled one another more strongly after the outbreak than they did before Bd invasion. I found no tadpoles within 22 months of the outbreak and limited signs of recovery within 10 years. In contrast, at the same site, for a population of male glass frogs, Espadarana prosopleon, I found that 10 years post-outbreak, the population was consistently half its historic abundance, and that the lack of recruits to the population explained why the population had not rebounded, rather than high pathogen-induced mortality. And finally, examining the entire amphibian community, I found high pathogen prevalence, low infection intensities, and high survival rates of uninfected and infected hosts. Bd transmission risk, i.e., the probability a susceptible host becomes infected, did not relate to host density, pathogen prevalence, or infection intensity– Bd transmission risk was uniform across the study area. My results are especially relevant to conservation biologists aiming to predict the future impacts of Bd outbreaks, those trying to manage persisting populations, and those interested in reintroducing species back into wild amphibian communities.

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Background: The survival rates of preterm infants has increased over the last years, but oral feeding difficulties are the most common problems encountered by them Objectives: This study aimed at comparing the effects of non-nutritive sucking (NNS) and pre-feeding oral stimulation on feeding skills, length of hospital stay and weight gain of 26-32 weeks gestational age preterm infants in NICU, to determine the more effective intervention. Patients and Methods: Thirty-two preterm infants were assigned randomly into three groups. One intervention group received pre-feeding oral stimulation program and the other received non-nutritive sucking stimulation, while the control group received a sham intervention. Gestational age of infants was calculated during 1, 4 and 8 oral feeding and discharge time from NICU. The infants’ weights were measured weekly from birth and at discharge time. Results: Mean gestational age on 8 time oral feeding per day, in 3 groups was not significant (P = 0.282). Although NNS and pre-feeding oral stimulation groups has fulfilled this criterion 7.55 and 6.07 days sooner than the control group, respectively (a result which is of great clinical and economic importance), but the difference did not reach statistical significance. Weight gaining at discharge time in NNS group was significantly higher than control and pre-feeding oral stimulation groups (P < 0.05). Conclusions: This study revealed that pre-feeding oral stimulation and NNS programs both were effective on oral feeding skills and weight gaining of the immature newborns. Yet, it seems that NNS program was more effective than pre-feeding oral stimulation on weight gaining.

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Background: There are a few published studies about prognostic markers of Epstein-B virus (EBV) related to outcomes in pediatric Hodgkin Lymphoma (HL). Objectives: We aimed to investigate the prognostic value and effect of EBV on survival by using biopsy materials in children and adolescents diagnosed with HL. Patients and Methods: EBV LMP-1 expression was examined using immunohistochemical methods in 58 tumor samples. Clinical features, overall survival (OS) and failure free survival time (FFS) were compared between EBV LMP-1 positive and negative patients. Results: In 20 (35%) patients tumors were LMP-1 positive. When compared with patients above 10 years old, EBV LMP-1 was often positive in patients under 10 years old (30% vs. 70%, P = 0.02). In our most cases having B symptoms and advanced stage, EBV positiveness in Hodgkin Reed-Stenberg cells (H-RS) was not a significant determinant for survival (P = 0.78). Half of the past clinical trials in childhood HL reported longer survival rates in EBV LMP-1 positive patients. In some trials similar to our results there was no significant relationship between EBV and prognosis. Conclusions: The reason of diminished EBV positiviness may be related to technical methods such as not using immunohistochemical and in situ hybridization for EBER antigen but in laboratory conditions painting of control tissues with EBV impair this probability. In addition, cases enrolled to our study were living in Istanbul where social and economical factors are improved rather than generally.