Lipidómica de fungos patogénicos em plantas e oportunistas em humanos do género Lasiodiplodia

The fungal kingdom comprises many complex and dangerous, yet misunderstood species. Pathogenic fungi are known to cause several detrimental effects to plants, animals, and humans. Lasiodiplodia genus belongs to the Botryosphaeriaceae family and causes disease on a variety of plant hosts but has also been reported to cause infections in humans. Lasiodiplodia theobromae and Lasiodiplodia hormozganensis are fungal crosskingdom pathogens, meaning that they can repeatedly infect organisms from different kingdoms of life. It is known that lipids produced by pathogenic fungi have important roles in the host-pathogen relationship. In order to further understand the pathogenic behaviour of species of the genus Lasiodiplodia, the aim of this study was to fully characterize the lipidome of L. theobromae and L. hormozganensis. For this purpose, liquid and gas chromatography coupled to mass spectrometry technology were used to identify phospholipids, sphingolipids, triacylglycerols and fatty acids. The different lipids present in the lipidome of both fungal species amounted to 255 molecular species. Because most lipids identified are present in both fungi, the total of identifications made was of 423. Regarding phospholipids, 147 molecular species of the classes phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, phosphatidic acid, cardiolipin, phosphatidylinositol, phosphatidylglycerol and phosphatidylserine were identified. Regarding sphingolipids, two ceramides were identified. In the triacylglycerol profile 83 molecular ions were identified, varying between TG C47 to C61. In the fatty acid profile 23 acids were identified, varying between FA C14 to C24. The most abundant fatty acids were C16:0, C16:1, C16:2, C18:0, C18:1, C18:2 and C18:3. Odd numbered fatty acids such as C15:0, C17:0 and C19:0 have also been observed in the lipidome of both species. In general, the lipidomic profiles of both species is very similar. This is the most complete study of the lipidome of Lasiodiplodia species until date. We hope this work can help to better understand fungal lipidomics and provide information on the lipids that constitute filamentous fungi, particularly plant pathogenic and human opportunistic species.O reino dos fungos inclui várias espécies complexas e perigosas, apesar de pouco entendidas. Os fungos patogénicos são conhecidos por causarem inúmeros efeitos nefastos em plantas, animais e humanos. O género Lasiodiplodia pertence à família Botryosphaeriaceae e inclui fungos que causam doenças em vários hospedeiros vegetais, mas que também têm sido reportados como causadores de infeção em humanos. Lasiodiplodia theobromae e Lasiodiplodia hormozganensis são duas espécies conhecidas pela sua capacidade de “cross-kingdom host jump”, isto é, por conseguirem infetar repetidamente organismos de diferentes reinos. Sabe-se que lípidos produzidos por fungos patogénicos têm papéis importantes na sua relação com os hospedeiros. De maneira a compreender melhor o comportamento patogénico de espécies do género Lasiodiplodia, o objetivo deste estudo foi caracterizar em detalhe o lipidoma de L. theobromae e L. hormozganensis. Para este propósito, foi utilizada a cromatografia líquida e gasosa associada à espectrometria de massa para identificar fosfolípidos, esfingolípidos, triacilgliceróis e ácidos gordos. Os diferentes lípidos presentes no lipidoma das espécies em estudo corresponderam a 255 espécies moleculares identificadas por LC-MS. Como a maioria dos lípidos identificados estão presentes em ambas as espécies, o total de identificações feito equivaleu a 423. Relativamente a fosfolípidos, foram identificadas 147 espécies moleculares das classes fosfatidilcolina, fosfatidiletanolamina, esfingomielina, ácido fosfatídico, cardiolipina, fosfatidilinositol, fofatidilglicerol e fosfatidilserina. Relativamente a esfingolípidos, foram identificadas duas ceramidas. No perfil de triacilgliceróis foram identificados 83 iões moleculares, que variaram entre TG C47 e TG C61. No perfil de ácidos gordos foram identificados 23 ácidos, que variaram entre FA C14 e C24. Os ácidos gordos mais abundantes foram C16:0, C16:1, C16:2, C18:0, C18:1, C18:2 e C18:3. Ácidos gordos ímpares como C15, C17 e C19 também foram observados no lipidoma de ambas as espécies. Em geral, o perfil lipídico das duas espécies é bastante semelhante. Este é o estudo mais completo do lipidoma de espécies de Lasiodiplodia realizado até à data. Esperamos que este trabalho possa ajudar a entender a lipidómica de fungos e fornecer informação acerca dos lípidos que constituem os fungos filamentosos, particularmente espécies patogénicas em plantas e oportunistas em humanos.Mestrado em Biotecnologi

Polymorphism & Parasites: Structure, Diversity and Selection of the MHCII Genes in a Weakly Electric Fish, Brachyhypopomus Occidentalis

The major histocompatibility complex (MHC) class II molecules play a key role in inducing an immune response, by presenting foreign peptides to T-lymphocytes. They are considered one of the most polymorphic genes in the vertebrate genome and diversity has been associated with species diversification mediated by parasite, viral and bacterial infections. While MHC genes are well documented in teleost fish, none thus far have been described in the Gymnotiform order – a highly diverse group of neotropical electric fishes. Using a combination of a recently annotated genome and whole genome resequencing data, I identified and characterized both the classical MHCII DAB, DAA and non-classical DBB genes in populations of the electric fish Brachyhypopomus occidentalis. I found highly polymorphic sites within the classical MHCII genes, and significant genetic divergence between populations widespread throughout the isthmus of Panama. To explore whether drift or selection is driving genetic diversity in MHCII genes, I compared variation between the MHCIIB and a neutral mitochondrial gene (COI). Geographic distance between sites was only correlated with variation in the COI gene, suggesting that selective pressures could be driving diversification in the MHCIIB. Further analysis showed that prevalence of parasites within drainages was associated with rate of non-synonymous mutations in the MHCIIB, which highlights the potential role parasites play in driving genetic diversity. Overall, my results highlight the highly polymorphic nature of the MHCII genes in electric fishes, and provides evidence for selection as a driver of variation at this locus. Although further analyses are needed, these findings contribute to a better understanding of what drives diversification in Neotropical electric fishes

Qualidade da água e estado trófico em um trecho do rio Cubatão Sul no município de Santo Amaro da Imperatriz – SC.

TCC(graduação) - Universidade Federal de Santa Catarina. Centro de Ciências Biológicas. Biologia.A demanda de consumo de água tem aumentado significativamente e a disponibilidade hídrica em condições de utilização para fornecimento à população não tem crescido na mesma proporção. O Rio Cubatão Sul, objeto de estudo que atravessa centros urbanos, é um manancial superficial de grande importância na região metropolitana de Florianópolis - SC. Além de ser essencial no equilíbrio do ecossistema abrigado, esse manancial é utilizado como fonte de água para abastecimento público e deve ter garantida a qualidade de suas águas. O presente estudo tem por objetivo caracterizar um trecho do Rio Cubatão Sul, localizado em Santo Amaro da Imperatriz, Santa Catarina, de acordo com o Índice de Estado Trófico (IET) para Fósforo e aplicar o Índice da Comunidade fitoplanctônica (ICF). De acordo com os resultados, o manancial, apesar de toda influência antrópica exercida sobre ele, apresenta bons resultados para os nutrientes analisados. O IET classifica o manancial como mesotrófico, ou seja, com produtividade intermediária. O ICF determinou que, nos dois pontos analisados, as águas do manancial estão classificadas entre Boa e Ótima

Effect of ph on the removal of fluoxetine from aqueous solutions by granular activated carbon

The widespread use of pharmaceuticals in human and veterinary medicine has led to the continuous release of these micropollutants and their metabolites into environmental matrices. The aim of this work is to assess the sorption capacity of activated carbon and to evaluate the effect of the solution pH on the removal of fluoxetine from dilute solutions (5 mg/L). Kinetic assays were performed in batch experiments at different pH values, from 2 to 9. The pH of zero point of charge, pHzpc, obtained for activated carbon was 8.3. The results revealed that the solution pH strongly influences the electrostatic interactions between the net surface charge of the adsorbent and the electric charge of fluoxetine molecules. The adsorption of fluoxetine onto activated carbon was therefore dependent on the solution pH, being the maximum uptake attained at pH 9 (q = 48.5 mg/g).info:eu-repo/semantics/publishedVersio

Social media in hotel crisis communication: a case study

The evolution of social media has transformed the way people communicate, share experiences and search for information before and after a trip. These platforms can bring countless benefits to businesses but implementing them effectively brings countless challenges. In the hotel industry, the use of social media as a digital marketing strategy has become fundamental to promote brands and services, as well as to create a closer relationship with the customer. It then becomes essential to understand how hotels can use these platforms effectively. Moreover, defining communication strategies, especially in periods of global crisis, with customers and public that include social networks are fundamental and a great challenge. In this sense, in this paper a case study of a hotel in a period including the global pandemic crisis of COVID-19 was conducted where good practices for social media management in hospitality are proposed, supported by the literature review and the practical learning provided in the fieldwork. These good practices also take into consideration the application of successful social media strategies in a hotel during times of crisis.info:eu-repo/semantics/publishedVersio

Towards glycoconjugate vaccines against carbapenem-resistance Klebsiella pneumoniae

Antimicrobial resistant bacteria account for high mortality rates due to the lack of effective methods to combat the pathogens. Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a bacterial group of huge concern that is resistant to nearly all available antibiotics. CRKP has been classified as an “urgent threat” to public health with a dire need to develop new drugs alternative treatments. Antibody therapy or even better, a vaccine, targeting this group would be a viable alternative to resolve this threat. Current strategies to target CRKP rely mostly on the bacterial capsular polysaccharides as antigens. However, the high variability in the CPS composition and low epidemiological correlation of clinical isolates would lead to vaccines with limited target spectrum and numerous antibodies for each CPS variant would be needed for acute treatment, making it a very costly approach. Contrary, O-antigens that are part of the bacterial LPS, account with just four serotypes for the majority of clinically relevant strains, with the O2afg serotype as the most frequent in the CRKP group. The use of native LPS-based antigens for vaccine development is hampered by the low immunogenicity, the lack of a T-cell dependent immune answer, and endotoxin contaminations in LPS batches, which can lead to lethal side effects. Thus, no LPS based vaccines are currently in development. In my thesis I address this bottleneck by exploring a semi-synthetic glycoconjugate vaccine using a highly pure and well-characterized synthetic oligosaccharide that mimics the native O2afg antigen of CRKP. The antigen was designed based on a hexasaccharide repeating unit of O2afg and synthesized by Dr. Dacheng Shen. The glycan was subsequently conjugated to CRM197, a carrier protein, and adsorbed into alum as adjuvant, creating a semi-synthetic glycoconjugate vaccine against CRKP based on approved and validated technology. I provide conclusive evidence that the novel glycoconjugate vaccine induces a strong T-cell dependent supported by an immune response with a long-term memory effect at very low antigen concentrations. The resulting antibodies activate complement deposition, thereby activating the opsophagocytic pathway. The generated antibodies are well suited for passive immunization and result in a significant improvement of several physiological parameters in a mouse model for acute pneumonia. This included lower levels of cytotoxic enzymes, neutrophil infiltration and the reduction of permeability and lung edema. Hospital-acquired pneumonia is the major problem caused by K. pneumoniae, especially among individuals with critical illness, for example HIV and cancer in intensive care units. Recently, the pathogen has also been associated with SARS-CoV-2 pulmonary co-infections contributing to chronic obstructive pulmonary diseases, a severe COVID-19 condition with high mortality rates. Thus, the antibodies would significantly reduce the burden as a result of co-infection and increase the chances of survival. I show that a highly effective and low cost glycoconjugate vaccine targeting conserved LPS structures can be developed based on proven technology and opens up for a safer alternative to fight antimicrobial resistant pathogens without the effect of evolutionary selection of resistant strain caused by the currently treatment with antibiotics

Evaluation of the physical properties of enamel submitted to at-home bleaching with different thickeners : an in situ study

Orientador: Debora Alves Nunes Leite LimaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: O objetivo deste estudo foi avaliar in situ a influência do peróxido de carbamida 10%(PC) contendo diferentes espessantes (carbopol, carbopol+glicerina e natrosol) sobre as características físicas do esmalte dental, como: cor, microdureza e rugosidade. Oitenta e quatro blocos de esmalte e dentina (4 × 4 × 2,5 mm) obtidos a partir de dentes bovinos foram manchados com chá preto, divididos em sete grupos (n=12) e fixados em dispositivos intra-bucais palatinos utilizados por 12 voluntários. Os espécimes foram submetidos a diferentes tratamentos: PC+carbopol (FGM), PC+carbopol+glicerina (Ultradent), PC+natrosol (Gel experimental), apenas com o gel de carbopol, apenas com o gel de glicerina+carbopol, apenas com gel de natrosol e sem nenhum tratamento (grupo controle). As propriedades físicas testadas foram cor (?E), rugosidade média (Ra) e microdureza Knoop (KHN). A morfologia da superfície de esmalte foi avaliada por microscopia de força atômica (AFM). Os dados foram submetidos à análise de variância (ANOVA) em esquema fatorial com tratamento adicional (2 x 3 +1), teste de Tukey e teste Dunnet. Como todos os pacientes receberam todos os tratamentos, o efeito "voluntário" foi inserido na análise de variância. Foi considerado o nível de significância de 5%. Entre as propriedades físicas avaliadas, quando avaliada a alteração de cor, todos os grupos apresentaram alteração, exceto o grupo não clareado com espessante carbopol, o qual foi semelhante ao grupo controle. Os grupos tratados com o espessante natrosol tiveram uma maior alteração na cor, apresentando-se mais claro que os demais. Com relação à microdureza, houve diminuição da mesma para os grupos tratados apenas com o gel de carbopol e com o gel de carbopol+glicerina, os quais diferiram do grupo controle. Para a rugosidade, houve aumento em todos os grupos clareados quando comparado com o grupo controle, porém o grupo PC+natrosol apresentou menor aumento. Dessa forma, pode-se concluir que a utilização de géis de clareadores contendo espessante natrosol promoveu menores alterações no esmalte do que géis clareadores com espessante carbopol e carbopol+glicerina, além de permitir um clareamento eficazAbstract: The objective of this study was to evaluate in situ the influence of carbamide peroxide 10% (PC) containing different thickeners on the physical characteristics of dental enamel, such as: color, microhardness and enamel roughness. Eighty-four blocks of enamel and dentin (4 × 4 × 2.5 mm) obtained from bovine teeth were divided into seven groups (n = 12) fixed in palatal intraoral devices used by 12 volunteers. The specimens were submitted to different treatments: PC + carbopol (FGM), PC + carbopol + glycerin (Ultradent), PC + natrosol (experimental gel), with carbopol gel only, with glycerin + carbopol gel, only with Natrosol gel and without any treatment (control group). The physical properties tested were color (?E), roughness (Ra) and Knoop microhardness (KHN). The morphology of the enamel surface was evaluated with atomic force microscopy (AFM). The data were submitted to analysis of variance (ANOVA) in a factorial scheme with additional treatment (2 x 3 +1), Tukey's test and Dunnet test. As all patients received all treatments, the "voluntary" effect was inserted in the analysis of variance. The level of significance was set at 5%. Among the physical properties evaluated, when the color change was evaluated, all the groups presented alteration, except the group treated only with carbopol thickener, which was similar to the control group. The groups treated with the thickener natrosol had a greater color change, being clearer than the others. Regarding the microhardness, there was a decrease in the same for the groups treated with carbopol gel and carbopol + glycerin gel, which differed from the control group. For roughness, there was an increase in all bleached groups when compared to the control group, but the PC + natrosol group presented a smaller increase. In this way it can be concluded that the use of bleaching gels containing natrosol thickener was less deleterious to the enamel than bleaching gels with carbopol thickeners and carbopol + glycerin, in addition to allowing an effective bleachingMestradoDentísticaMestra em Clínica Odontológic