Qualidade de vida: nutrição, higiene e segurança dos alimentos.

bitstream/item/128275/1/EMA-5-VIDA.pdfProjeto Minibibliotecas

Coordinated regulation of the ESCRT-III component CHMP4C by the chromosomal passenger complex and centralspindlin during cytokinesis

The chromosomal passenger complex (CPC)-composed of Aurora B kinase, Borealin, Survivin and INCENP-surveys the fidelity of genome segregation throughout cell division. The CPC has been proposed to prevent polyploidy by controlling the final separation (known as abscission) of the two daughter cells via regulation of the ESCRT-III CHMP4C component. The molecular details are, however, still unclear. Using atomic force microscopy, we show that CHMP4C binds to and remodels membranes $\textit{in vitro}$. Borealin prevents the association of CHMP4C with membranes, whereas Aurora B interferes with CHMP4C's membrane remodelling activity. Moreover, we show that CHMP4C phosphorylation is not required for its assembly into spiral filaments at the abscission site and that two distinctly localized pools of phosphorylated CHMP4C exist during cytokinesis. We also characterized the CHMP4C interactome in telophase cells and show that the centralspindlin complex associates preferentially with unphosphorylated CHMP4C in cytokinesis. Our findings indicate that gradual dephosphorylation of CHMP4C triggers a 'relay' mechanism between the CPC and centralspindlin that regulates the timely distribution and activation of CHMP4C for the execution of abscission.This work was supported by Cancer Research UK grant no. C12296/A12541 to P.P.D., who is also the recipient of the Maplethorpe Fellowship from Murray Edwards College, Cambridge, UK. I.M. and J.M.E. were supported by Biotechnology and Biological Research Council grant no. BB/J018236/1. A.A.J. is supported by Wellcome Trust Career Development grant no. 095822 and European Commission Career Integration grant no. 334291

Estudo do potencial de degradação de toxina Cry por bactéria isolada de solo. I - Estudo da influência do pH e do tampão de ativação.

Microrganismos da rizosfera sofrem influência direta de exsudados de raízes das plantas. Plantas transgênicas podem exsudar novas proteínas produzidas a partir de respostas de genes instalados nessas plantas, o que poderia gerar impactos à microbiota do solo. Este trabalho teve por objetivo avaliar a dinâmica de crescimento de um microrganismo isolado em meio mínimo, a partir de solo rizosférico de algodão Bt, em dois pH e na presença e ausência de tampão carbonato (tampão de ativação). Estas respostas são essenciais para a etapa futura do trabalho de estudo da degradação da proteína Cry. O crescimento foi realizado em meio mínimo líquido mineral, a pH 7,0 e 8,0 na presença e ausência de tampão ativador da proteína, a 180 rpm, 28º C por 72 horas. Verificou-se o crescimento bacteriano, em nutriente ágar, após 48 horas de incubação a 28º C, sendo expresso em unidades formadoras de colônias por mL (UFC/mL). Observou-se que não houve diferença significativa entre os crescimentos a diferentes pH e na presença ou ausência do tampão

A novel BRCA2 splice variant identified in a young woman

Background: BRCA1/2 VUSs represent an important clinical issue in risk assessment for the breast/ovarian cancer families (HBOC) families. Among them, some occurring within the intron-exon boundary may lead to aberrant splicing process by altering or creating de novo splicing regulatory elements or unmasking cryptic splice site. Defining the impact of these potential splice variants at functional level is important to establish their pathogenic role. Methods: Genomic DNA was extracted from peripheral blood sample of a young woman affected with breast cancer belonging to a HBOC family and the entire coding regions of the BRCA1 and BRCA2 genes were amplified using the Ion AmpliSeq BRCA1 and BRCA2 Panel. The BRCA2 c.682-2delA variant has been characterized by RT-PCR analysis performed on mRNA extracted from blood and lymphoblastoid cell line. Results: We demonstrated that a novel BRCA2 c.682-2delA variant at the highly conserved splice consensus site in intron 8 disrupts the canonical splice acceptor site generating a truncated protein as predicted by several bioinformatics tools. Segregations analysis in the family and LOH performed on proband breast cancer tissue further confirmed its classification as pathogenic variant. Conclusion: Combining different methodologies, we characterized this new BRCA2 variant and provided findings of clinical utility for its classification as pathogenic variant

Manipueira: its use in obtaining a biofungicide.

In the search for an alternative to the intensive use of fungicides in crop production, a soil bacterium was isolated in Guaira, Sao Paulo State (Brazil). This Bacillus gave good control of the fungus Fusarium solani, an important plant disease. In order to apply this bacterium in larger experimental areas, it was necessary to study its production by liquid fermentation on cheap agroindustrial residues. Manipueira (the waste water from cassava flour industry) was the main component of the medium, supplemented by sugarcane molasses. It was inoculated with the Bacillus sp. (isolated from Guaira soil) and incubated under constant agitation and temperatura in 250 ml Erlenmeyer flasks. Bacterial growth, pH and sugar consumption were analyzed over 48 h of fermentation. The results obtained indicated the ability of the residue to support the growth of the strain tested and the importance of scaling up the fermentation process

HER2-positive male breast cancer: An update

none7noAlthough rare, male breast cancer (MBC) remains a substantial cause for morbidity and mortality in men. Based on age frequency distribution, age-specific incidence rate pattern, and prognostic factor profiles, MBC is considered similar to postmenopausal breast cancer (BC). Compared with female BC (FBC), MBC cases are more often hormonal receptor (estrogen receptor/progesterone receptor [ER/PR]) positive and human epidermal growth factor receptor 2 (HER2) negative. Treatment of MBC patients follows the same indications as female postmenopausal with surgery, systemic therapy, and radiotherapy. To date, ER/PR and HER2 status provides baseline predictive information used in selecting optimal adjuvant/neoadjuvant therapy and in the selection of therapy for recurrent or metastatic disease. HER2 represents a very interesting molecular target and a number of compounds (trastuzumab [Herceptin®; F. Hoffmann-La Roche, Basel, Switzerland] and lapatinib [Tykerb®, GlaxoSmithKline, London, UK]) are currently under clinical evaluation. Particularly, trastuzumab, a monoclonal antibody which selectively binds the extracellular domain of HER2, has become an important therapeutic agent for women with HER2-positive (HER2+) BC. Currently, data regarding the use of trastuzumab in MBC patients is limited and only few case reports exist. In all cases, MBC patients received trastuzumab concomitantly with other drugs and no severe toxicity above grade 3 was observed. However, MBC patients that would be candidate for trastuzumab therapy (ie, HER2+/ER+ or HER2+/ER- MBCs) represent only a very small percentage of MBC cases. This is noteworthy, when taking into account that trastuzumab is an important and expensive component of systemic BC therapy. Since there is no data supporting the fact that response to therapy is different for men or women, we concluded that systemic therapy in MBC should be considered on the same basis as for FBC. Particularly in male patients, trastuzumab should be considered exclusively for advanced disease or high-risk HER2+ early BCs. On the other hand, lapatinib (Tykerb), a novel oral dual tyrosine kinase inhibitor that targets both HER2 and epidermal growth factor receptor, may represent an interesting and promising therapeutic agent for trastuzumab-resistant MBC patients.openOttini L.; Capalbo C.; Rizzolo P.; Silvestri V.; Bronte G.; Rizzo S.; Russo A.Ottini, L.; Capalbo, C.; Rizzolo, P.; Silvestri, V.; Bronte, G.; Rizzo, S.; Russo, A