Engineered genetic tools for directed gene regulation

Genetic manipulation or genetic engineering is the ability to modify the behaviour of a gene or group of genes. In biological research, since nucleic acids were shown to be responsible for control of cellular functions and transfer of biological information, the urge to understand how genetic material works led to the development of tools in order to manipulate gene expression. Genetic manipulation is a powerful tool for biological research and the clinics. The improvement and development of gene manipulation techniques as well as gene delivery tools is crucial for the success and advancements of the field. In this thesis, we aimed to produce gene delivery tools that are more specific and efficient on delivering a gene of interest. We also aimed to utilise our delivery tools to test effective gene manipulation techniques to assist us on answering interesting scientific questions: Is the CRLF3 receptor linked to Epo mediated neuroprotection in mammals? Does a snoRNA derived miRNA behave as a classical miRNA

Diferentes embalagens na conservação pós-colheita do minitomate Sweet Grape

Objetivou-se avaliar a vida útil do minitomate (Lycopersicum esculentum Mill.), variedade Sweet Grape, produzido em hidroponia e armazenado sob condição ambiente e refrigerada, em diferentes embalagens. Adotou-se o delineamento experimental inteiramente casualizado, em que os tratamentos consistiram na combinação da condição de armazenamento: ambiente (a) e refrigerada (r), e tipo de embalagem: filme flexível de policloreto de vinila (PVC); polietileno de baixa densidade (PEBD); biofilme de fruto de Solanum lycocarpum A.St.-Hil (lobeira) (BFL); biofilme de fécula de mandioca (BFM); cera de Copernicia prunifera (carnaúba) (CC), e sem embalagem - testemunha (T). As análises físico-químicas e sensoriais foram realizadas no início (dia zero), aos 8, 19 e 33 dias de armazenamento (DA). Os frutos submetidos às embalagens PVCr, PEBDa, PEBDr e CCr apresentam vida útil aceitável de 33 dias de armazenamento. A aplicação de biofilmes de amidos de fruto de lobeira e mandioca não é eficaz no controle da perda de massa fresca. A condição refrigerada é a melhor forma para a conservação pós-colheita dos frutos de minitomate. O tratamento CCr é o que mais agrada os julgadores, e o PCV, o de maior índice de rejeição.This paper aims at evaluating the shelf life of mini tomatoes (Lycopersicum esculentum Mill.) cultivar ‘Sweet Grape’, grown in hydroponics, and stored under environmental and refrigerated conditions inside different packages. We adopted a completely randomized design, in which treatments were combinations of storage conditions: environment (e) and refrigerated (r) with packaging: polyvinyl chloride film (PVC); low-density polyethylene (LDPE); biofilm of tomato fruit of Solanum lycocarpum A.St.-Hil (lobeira) (TFB); cassava starch biofilm (CSB); carnauba wax (Copernicia prunifera) (CW), and without packaging - control (C). Physicochemical and sensory tests were carried out at the beginning (day zero), and at 8, 19, and 33 days of storage (DS). Fruit stored inside PVCr, LDPEe, LDPEr, and CWr had an acceptable shelf life of 33 days. The use of cassava and tomato starches were not effective in controlling fruit fresh weight loss. ‘Sweet Grape’ tomato postharvest conservation was enhanced under refrigerated conditions. The sensory evaluation results revealed that CWr treatment most pleased appraisers, while PCV had the highest rejection rate

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Enhanced Production of Exosome-Associated AAV by Overexpression of the Tetraspanin CD9

Research on cell-free vesicles revealed a multitude of characteristics, in particular of microvesicles and exosomes, that range from their potential as biomarkers to a function in horizontal transfer of genetic information from cell to cell and also include supportive functions in viral infection. Exosome-associated adeno-associated viruses (exo-AAVs) are of particular interest for the past couple of years, because they introduced a new source of highly potent recombinant AAVs with improved features, including accelerated transduction rates and more efficient immune escape. However, key factors like the mode of action, efficiency of production, or engineering of exo-AAVs remain elusive to a large extent. Here, we used the established system of CD9 overexpression to boost the exosome output of AAV producing HEK-AAV cells. The CD9-powered high-exosome environment was established during exo-AAV1 production, and we could demonstrate that the yield of exo-AAVs dramatically increased when compared to standard exo-AAVs. Furthermore, we report that exo-AAV-CD9GFP was more efficient in transduction of cells in the same titer ranges as standard exo-AAVs. Our results provide a technological approach for the generation of exo-AAVs with superior performance. Keywords: exosomes, recombinant AAV, CD9, exo-AAV, gene delivery, viral vecto

Gastrointestinal parasites in feral cats and rodents from the Fernando de Noronha Archipelago, Brazil

Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37) and rodents (n = 30) from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago

Hydrological Effects on the Reproduction of the Giant South American River Turtle Podocnemis expansa (Testudines: Podocnemididae)

Understanding the relationship between species and the environment is crucial to predicting their responses to human-induced global changes, i.e., habitat conversion, biological invasions, and global warming. Precipitation and river level are relevant factors that regulate the populations of aquatic organisms. We used long-term data to assess the effects of climate on nest number, clutch size (number of eggs per nest), hatching success, and unviable eggs of the Giant South American River Turtle (Podocnemis expansa) in a protected area of Brazilian Amazonia. We found a positive relationship between the number of nests and precipitation on headwaters in May. We also observed that clutch size increased when the local river level rose; hatching success increased with rising local river level, mainly during October and November; and egg failure increased with rising headwater river level. We show how precipitation and river level (at local and headwater) can influence reproductive success in P. expansa, highlighting the perils of human-induced environmental changes.Fil: Simoncini, Melina Soledad. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina. Universidade Federal Do Tocantins; BrasilFil: Campos De Sousa, Heitor. Universidade Federal Do Tocantins; BrasilFil: Costa Gonçalves Portelinha, Thiago. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina. Universidade Federal Do Tocantins; BrasilFil: Falcon, Guth Berger. Instituto Chico Mendes de Conservação da Biodiversidade; BrasilFil: Collicchio, Erich. Universidade Federal Do Tocantins; BrasilFil: Machado Balestra, Rafael A.. Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios; BrasilFil: Ferreira Luz, Vera L.. Centro Nacional de Pesquisa e Conservação de Répteis e Anfíbios; BrasilFil: Colli, Guarino Rinaldi. Universidade do Brasília; BrasilFil: Malvásio, Adriana. Universidade Federal Do Tocantins; Brasi