Elucidating oncogenic mechanisms in human B cell malignancies

This study consists of two pieces of work investigating haematological malignancies; Acute Lymphoblastic Leukaemia (ALL) and Diffuse Large B Cell Lymphoma (DLBCL). Firstly, Pre-B ALL represents the most common paediatric malignancy and despite increasingly improved outcomes for patients, ~ 20% of all patients diagnosed with ALL relapse. Activating mutations in the RAS pathway are common (~50%) and result in hyperactivation of the MAPK pathway. I identified Erk negative feedback control via DUSP6 to be crucial for NRASG12D-mediated pre-B cell transformation and investigated its potential as a therapeutic target. I showed that a small molecule inhibitor of DUSP6 (BCI) selectively induced cell death in patient-derived pre-B ALL cells; with a higher sensitivity observed in relapse pre-B ALL. I also discovered that a high level of Erk activity is required for proliferation of normal pre-B cells, but dispensable in leukemic pre-B ALL cells. In addition, I found that human B cell malignancies can be grouped into three categories that fundamentally differ in their ability to control Erk signalling strength. Secondly, DLBCL is the most common haematological malignancy and although potentially curable with chemotherapy, 40% of patients still succumb from their disease. Recent exome sequencing studies have identified hundreds of genetic alterations but, for most, their contribution to disease, or their importance as therapeutic targets, remains uncertain. I optimised a novel approach to screen the functional importance of these mutations. This was achieved by reconstituting non-malignant, primary, human germinal centre B cells (GC B cells) with combinations of wildtype and mutant genes to recapitulate the genetic events of DLBCL. When injected into immunodeficient mice, these oncogene-transduced GC B cells gave rise to tumours that closely resemble human DLBCL, reinforcing the biological relevance of this system. To screen potential tumour suppressor mutations in this system in a high throughput fashion, I developed a lymphoma-focused CRISPR library of 692 genes recurrently altered in B cell lymphomas. These experiments identified GNA13 as an unexpectedly potent tumour suppressor in human GC B cells and provided new understanding to its mechanism of action. These findings provide novel understanding of the complexity of oncogenic mechanisms in human B cell malignancies

Modelagem do efeito antagônico de Lactobacillus sobre Escherichia coli, Listeria monocytogenes e Staphylococcus aureus pela análise de sobrevivęncia com enfoque Bayesiano /

Orientador: Carlos Ricardo SoccolCo-orientador: José Luiz ParadaInclui apęndiceDissertaçăo (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduaçao em Processos Biotecnológicos. Defesa: Curitiba, 2007Inclui bibliografia e anexo

Genetic manipulation and immortalized culture of ex vivo primary human germinal center B cells.

Next-generation sequencing has transformed our knowledge of the genetics of lymphoid malignancies. However, limited experimental systems are available to model the functional effects of these genetic changes and their implications for therapy. The majority of mature B-cell malignancies arise from the germinal center (GC) stage of B-cell differentiation. Here we describe a detailed protocol for the purification and ex vivo expansion of primary, nonmalignant human GC B cells. We present methodology for the high-efficiency transduction of these cells to enable combinatorial expression of putative oncogenes. We also describe alternative approaches for CRISPR-Cas9-mediated deletion of putative tumor suppressors. Mimicking genetic changes commonly found in lymphoid malignancies leads to immortalized growth in vitro, while engraftment into immunodeficient mice generates genetically customized, synthetic models of human lymphoma. The protocol is simple and inexpensive and can be implemented in any laboratory with access to standard cell culture and animal facilities. It can be easily scaled up to enable high-throughput screening and thus provides a versatile platform for the functional interrogation of lymphoma genomic data.D.H. was personally supported by a Clinician Scientist Fellowship from the Medical Research Council (MR/M008584/1). Research in the Hodson laboratory is supported by the Kay Kendall Leukaemia Fund, The Addenbrooke’s Charitable Trust and the Evelyn Trust. The Hodson laboratory receives core funding from Wellcome (203151/Z/16/Z) and MRC to the WellcomeMRC Cambridge Stem Cell Institute and from CRUK to the CRUK Cambridge Centre (A25117

HCP report no. 12 : the state of household food security in Cape Town, South Africa

High levels of inequality in food security are consistent with findings in the broader literature on poverty and inequality across the city of Cape Town. This is the first city-wide representative household food security survey of Cape Town. The main finding is that the food system does not service all residents equally. From a food system perspective, the Hungry Cities Food Purchases Matrix (HCFPM) findings are presented and analyzed in depth and confirm that supermarkets dominate food purchases with 94% of households patronizing them. Urban agriculture and informal food are important to poorer communities, but ignored in city policy.Social Sciences and Humanities Research Council (SSHRC

Meta-análise de estudos sobre o efeito do fogo nos biomas florestais em relação aos microrganismos fúngicos

O fogo é um elemento da mudança global que pode influenciar as comunidades fúngicas, com o intuito de compreender como o incêndio afeta essas comunidades, foi realizado uma revisão sistemática com uma metanálise de 30 estudos que abordam ou com o tema respostas fúngicas ao fogo. Os estudos selecionados 56,67% obtêm resultados positivos para o uso da função pública e 43,33% dos efeitos negativos, 56,66% das análises de microrganismos fúngicos que foram utilizados pela coleta de solo. Como as respostas dos microrganismos fúngicos ao fogo diferem entre os tipos de vegetação, uma biomassa fúngica que queima queimaduras em flores boreais, mas não ocorre depois de queimadas em flores e temperadas florestais, uma floresta tropical não comparada entre os florestais e os medicamentos prescritos.Foi registrado nesta meta-análise que os incêndios florestais levam a uma redução maior da comunidade fúngica que queimada prescrita. Os mecanismos ou processos responsáveis pela diversidade de espécies de fungos após o uso do fogo tanto para queimaduras como queimaduras permanentes são desconhecidas. Desta forma, uma padronização das metodologias é necessária para realizar comparações entre os estudos da mesma tipologia de vegetação

Estudos de efeito antagônico entre Lactobacillus sakei em Escherichia coli, Listeria monocytogenes e Staphylococcus aureus

The antimicrobial activity of a commercial probiotic culture, Lactobacillus sakei(ATCC 1521) at followingconcentrations (30, 42, 60, 78 and 90 μg/ml, 105 - 107UFC/mL), temperatures of interaction (4, 10, 20, 30, 37 °C) and initial pH (3.5, 4.0, 4.5, 5.0 and 5.5) were tested against three foodborne pathogens, Escherichia coli, Listeria monocytogenesand Staphylococcus aureus. The antagonistic effect of the probiotic culture in vitro was performed by liquid microdilution method. The results indicated that the inhibitory substance present on a 24 hours culture broth could be an advantage when keeping the culture dominant during longer fermentations. For the highest lactic acid production, the incubation period of lactic acid bacteria (1.04 % v/v) was on MRS Broth in aerobic conditions, at 37 ºC/24 hours, which gave a minimum pH value of the supernatant (3.5). The data suggest that supernatant can have significant bacteriostatic activity against E. coli, L. monocytogenesand S. aureus, and may provide curedmeats with a degree of protection against this microorganism, particularly if employed with a combination of acid pH, and adequate refrigeration.A atividade antimicrobiana de uma cultura comercial probiótica  deLactobacillus  sakei  (ATCC  1521)  foi avaliada em termos de concentração celular (30, 42, 60, 78 e 90 mcg / ml, 105 - 107UFC/mL), temperatura de incubação (4, 10, 20, 30, 37 ° C) e pH inicial do meio de cultura (3.5, 4.0, 4.5, 5.0 e 5.5) contra três patógenos alimentares, Escherichia coli, Listeria monocytogenes e Staphylococcus aureus. O efeito antagônico da cultura probiótica in vitro foi realizada através da aplicação de método quantitativo espectrofotométrico. Os resultados indicaram que uma substância inibitória presente em caldo de cultura de 24 horas poderia ser vantajoso quando mantendo a cultura dominante durante fermentações mais prolongadas. Para a maior produção de ácido láctico (1,04%v/v), o período de incubação da bactéria em caldo MRS foi de 24 horas em condições aeróbicas e a 37 ºC, com um valor de pH mínimo do sobrenadante (3,5). Os dados sugerem que o sobrenadante pode ter atividade bacteriostática significativa contra E. coli,L. monocytogenes e S. aureus, e pode fornecer carnes curadas com um grau de protecção contra este microorganismo, particularmente se empregada com uma combinação de pH ácido, e de refrigeração adequada

SOFTWARES LIVRES E EQUIPAMENTOS MANUFATURADOS: possíveis recursos para a integração curricular das TDIC

This article reports an experience of teacher training, with an emphasis on computational thinking, through videotape production. A multimedia studio was created using the technological resources of LIFE (computer, multimedia projector, TV and digital slate) and manufactured mechanisms of alternative materials. We also prioritized the softwares and free platforms, described in this article. The videotapes produced by the pilot group have shown that the curriculum integration of digital media, despite lacking public policies committed to a medium and long term process, can be enhanced through existing resources in educational institutions and through the creation of networks of sharing of products and practices.   KEYWORDS: digital technologies; computational thinking; videotapes, teacher training; alternative materials.Este artículo relata una experiencia de formación de profesores, con énfasis en el pensamiento computacional, vía producción de videojuegos. Se creó un estudio multimedia utilizando los recursos tecnológicos de LIFE (ordenador, proyector multimedia, TV y pizarra digital) y mecanismos manufacturados de materiales alternativos. También se han priorizado los softwares y plataformas libres, descritos en este artículo. Las videocas producidas por la clase piloto mostraron que la integración curricular de los medios digitales, a pesar de carecer de políticas públicas comprometidas con un proceso de mediano y largo plazo, puede ser potencializada a través de recursos existentes en las instituciones educativas y por la creación de redes de distribución de los productos y prácticas desarrolladas.   PALABRAS CLAVE: Tecnologías digitales; Pensamiento computacional; videoconferencia, formación de profesores; materiales alternativos.Este artigo relata uma experiência de formação de professores, com ênfase no pensamento computacional, via produção de videoaulas. Foi criado um estúdio de multimídia utilizando os recursos tecnológicos do LIFE (computador, projetor multimídia, TV e lousa digital) e mecanismos manufaturados de materiais alternativos. Também foram priorizados os softwares e plataformas livres, descritos neste artigo. As videoaulas produzidas pela turma piloto mostraram que a integração curricular das mídias digitais, apesar de carecer de políticas públicas comprometidas com um processo de médio e longo prazo, pode ser potencializada via recursos existentes nas instituições educacionais e pela criação de redes de compartilhamento dos produtos e práticas desenvolvidas.   PALAVRAS-CHAVE: tecnologias digitais; pensamento computacional; videoaulas, formação de professores; materiais alternativos.   ABSTRACT This article reports an experience of teacher training, with an emphasis on computational thinking, through videotape production. A multimedia studio was created using the technological resources of LIFE (computer, multimedia projector, TV and digital slate) and manufactured mechanisms of alternative materials. We also prioritized the softwares and free platforms, described in this article. The videotapes produced by the pilot group have shown that the curriculum integration of digital media, despite lacking public policies committed to a medium and long term process, can be enhanced through existing resources in educational institutions and through the creation of networks of sharing of products and practices.   KEYWORDS: digital technologies; computational thinking; videotapes, teacher training; alternative materials.   RESUMEN Este artículo relata una experiencia de formación de profesores, con énfasis en el pensamiento computacional, vía producción de videojuegos. Se creó un estudio multimedia utilizando los recursos tecnológicos de LIFE (ordenador, proyector multimedia, TV y pizarra digital) y mecanismos manufacturados de materiales alternativos. También se han priorizado los softwares y plataformas libres, descritos en este artículo. Las videocas producidas por la clase piloto mostraron que la integración curricular de los medios digitales, a pesar de carecer de políticas públicas comprometidas con un proceso de mediano y largo plazo, puede ser potencializada a través de recursos existentes en las instituciones educativas y por la creación de redes de distribución de los productos y prácticas desarrolladas.   PALABRAS CLAVE: Tecnologías digitales; Pensamiento computacional; videoconferencia, formación de profesores; materiales alternativos

Determining water content and other impurities in Siparuna guianensis Aublet essential oil using differential scanning calorimetry

Siparuna guianensis Aublet is a predominant species in the Brazilian Cerrado. Some studies found that its essential oil has properties that could be useful for manufacturing new products. Its quality depends on physicochemical properties, since its degradation, as well as water content and other volatile materials may cause several changes in its features. The differential scanning calorimetry (DSC) was used to determine the water content in the S. guianensis essential oil in order to evaluate its thermal parameters. The method is based on the hypothesis that the desolvation enthalpy (ΔHdesol) needed for removing n water moles from the essential oil is approximately the enthalpy needed for melting the same n water moles (nΔHf). Thus, the current study considers the dissociation enthalpy (ΔHdiss) to be negligible. The total number of moles was calculated from the molecular mass value of the main essential oil components mentioned in the literature. The DSC curve in nitrogen atmosphere indicated the melting temperature of 1.6°C (ΔH=18.95 Jg-1). Based on the dehydration enthalpies demonstrated in the DSC curve, it was possible to infer that the calculations on the number of water moles and other constant volatile materials found in the S. guianensis essential oil were compatible with Karl Fischer Titration (KFT) method. This method is commonly used to determine the water content in substances.Key words: Siparuna guianensis, differential scanning calorimetry, thermogravimetric analyses