151 research outputs found
Diagramación de guía metodológica del programa EPSUM dirigido a los estudiantes de EPS de la USAC, así como infografías de apoyo en el material educativo y diseño de página web para la divulgación de información programa.
Diseño de la página web, y de los recursos gráficos digitales, para la información y la divulgación de la labor que el programa de becas EPSUN, brinda a los estudiantes próximos a realizar el Ejercicio Profesional Supervisado -EPS-; y de las acciones de integración entre los equipos multiprofesionales con los estudiantes de los programas EPS, PPS y DDC
Study of PMT target specificity in Ustilago maydis
Ustilago maydis is a pathogenic fungi responsible for the corn smut fungus disease, which causes a significant loss in mayze production every year. The PMT is a family of well-conserved O-mannosylating proteins. In Ustilago maydis, the deletion of Pmt2 has been shown to be deleterious and the deletion of Pmt4 disrupts completely the infectious process; on the other hand, the deletion of Pmt1 doesn't manifest any phenotype. All PMT proteins have three domains, named PMT, MIR and 4TMC, and several transmembrane regions. We hipothesized that one of these domains of Pmt4 is responsable for the substrate specificity that confers the virulence phenotype in Ustilago maydis Pmt4 and, if this would be the case, we could develop an antifungal drug specific to this domain. To check this, we built three chimerical protein strains, chanching one domain in Pmt4 for the same domain of Pmt1 at a time, and measure the tumor formation in 3 independent experiments. We also built a full Pmt4 length strain as a positive control. The results indicate that either the protein requires all three Pmt4 domains to infect or the chimerical protein is not working properly.Furthermore, we also wanted to check what region gives Pmt2 its specificity for growth. In Schizosaccharomyces pombe, a ortholog of Pmt2, named Ogm2, present the same essencial-for-growth phenotype than in U. maydis. Since U. maydis doesn't have any repressable promoter, we built a S. pombe strain with the shut-off promoter nmt81 in the endougenous Ogm2 gene and will complement the phenotype with mutagenized plasmids containing the U. maydis Pmt2 and measure its viability.Finally, we also plan to build other three strains interchanching Pmt4 domains in the Pmt1 protein
Individual and Joint Effect of Alpha-Tocopherol and Hydroxytyrosol Acetate on the Oxidation of Sunflower Oil Submitted to Oxidative Conditions: A Study by Proton Nuclear Magnetic Resonance
[EN] This study tackles the individual and joint effect of alpha-tocopherol and hydroxytyrosol acetate on the oxidation of sunflower oil submitted to accelerated storage conditions at intermediate temperature, in order to deepen the understanding of antioxidant–prooxidant behaviour. This was accomplished by 1H Nuclear Magnetic Resonance. For this purpose, the evolution of the degradation of both the main components of the oil and the aforementioned added compounds was monitored by this technique throughout the storage time. Furthermore, the formation of a very large number of oxylipins and the evolution of their concentration up to a very advanced stage of oil oxidation, as well as the occurrence of lipolysis, were also simultaneously studied. The results obtained show very clearly and thoroughly that in the oxidation process of the oil enriched in binary mixtures, interactions occur between alpha-tocopherol and hydroxytyrosol acetate that notably reduce the antioxidant effect of the latter compound with the corresponding negative consequences that this entails. The methodology used here has proved to be very efficient to evaluate the antioxidant power of mixtures of compoundsThis work has been funded by the Spanish Ministry of Science and Innovation (MINECO,
AGL2015-65450-R, AEI/FEDER-EU) and by the Basque Government and its Departments of Univer-
sities and Research (EJ-GV, IT-916-16
Influence of Hydroxytyrosol Acetate Enrichment of an Oil Rich in Omega-6 Groups on the Evolution of Its Oxidation and Oxylipin Formation When Subjected to Accelerated Storage. A Global Study by Proton Nuclear Magnetic Resonance
Sunflower oil samples, both unenriched and enriched with four different concentrations of hydroxytyrosol acetate, were subjected to accelerated storage at 70 °C until a very advanced oxidation stage and the process was monitored by 1H NMR spectroscopy. The aim of the study is to know the effect that the presence of this antioxidant has on the oxidation process of sunflower oil under the aforementioned conditions, as well as on the formation and evolution of the concentration of a significant number of oxylipins. The oxidation process was studied globally by monitoring, during storage time, the degradation of both the linoleic acyl group of sunflower oil, which is the main component of sunflower oil, and the added hydroxytyrosol acetate. Simultaneously, the identification of up to twenty-six different types of oxylipins formed in the oxidation process and the monitoring of the evolution of their concentration over the storage time were carried out. In this way, essential information about the effect that hydroxytyrosol acetate provokes on the oxidation of this oil rich in omega-6 polyunsaturated acyl groups, has been obtained. It has also been shown that the enrichment of sunflower oil with this antioxidant under the conditions tested does not prevent the oxidation process but slows it down, affecting the entire oxidation process.This work has been funded by the Spanish Ministry of Science and Innovation (MINECO, AGL2015-65450-R, AEI/FEDER-EU) and by the Basque Government and its Departments of Universities and Research (EJ-GV, IT-916-16
Alpha-Tocopherol, a Powerful Molecule, Leads to the Formation of Oxylipins in Polyunsaturated Oils Differently to the Temperature Increase: A Detailed Study by Proton Nuclear Magnetic Resonance of Walnut Oil Oxidation
Lipid oxidation causes food degradation and the formation of toxic compounds. Therefore, the addition to foods of compounds able to avoid, delay or minimize this degradative process is a commonly used strategy. Nevertheless, neither the identity of most of the formed compounds in this complex process nor the way in which their formation is affected by the strategy used are well known. In this context, the effect the temperature increase and the enrichment level in alpha-tocopherol on the evolution of the walnut oil oxidation, as a model of an oil rich in polyunsaturated omega-6 acyl groups, submitted to storage conditions, are tackled by 1H NMR. The study has allowed knowing the degradation kinetic of both the oil acyl groups and alpha-tocopherol, the identification of a very high number of oxylipins and the kinetic of their formation. The temperature increase accelerates the formation of all oxylipins, favouring the formation of hydroperoxy conjugated E,E-dienes and related derivatives versus that of the Z,E-isomers. The enrichment in alpha-tocopherol accelerates the formation of hydroperoxy conjugated Z,E-dienes and related derivatives, and delays in relation to the formation of the former that of the E,E-isomers and related derivatives, hindering, to a certain extent, the formation of the latter in line with the enrichment level.This work has been funded by the Spanish Ministry of Science and Innovation (MINECO, AGL2015-65450-R, AEI/FEDER-EU) and by the Basque Government and its Departments of Universities and Research (EJ-GV, IT-916-16)
Liposomas decorados con Apo2L/TRAIL como tratamiento antitumoral de tumores sólidos
El propósito principal de este trabajo de fin grado consiste en llevar a cabo la purificación de la proteína Apo2L/TRAIL (TRAIL) y unirla a la superficie de nanopartículas lipídicas (LUV-TRAIL) con el objetivo de usarla como tratamiento antitumoral en tumores sólidos, en concreto de colon, para lo cual se utilizó la línea celular HCT-116 y de riñón empleando la línea celular Caki-1. Para ello, se ha llevado a cabo la purificación de dicha proteína, y la generación de las nanopartículas lipídicas y posteriormente se unió la proteína a su superficie para analizar su bioactividad y capacidad como tratamiento antitumoral comparándola con la proteína soluble. Apo2l/TRAIL es un ligando mortal que interaccionan con sus receptores pro-apoptóticos en células tumorales activando la vía extrínseca de la apoptosis e induciendo la muerte de células cancerosas. Por ello, antes de llevar a cabo los ensayos de citotoxicidad se estudió en ambas líneas la expresión de los receptores de Apo2L/TRAIL. Una vez confirmada ésta, se llevaron a cabo estudios de la citotoxicidad de los LUV-TRAIL comparándolos con TRAIL soluble realizando ensayos dosis-respuesta y se analizó la muerte de las células tumorales mediante citometría de flujo y MTT. También se emplearon durante estos experimentos un anticuerpo bloqueante específico de TRAIL; RIK, con el objetivo de demostrar que la muerte inducida por los LUV-TRAIL en dichas líneas se debe específicamente a TRAIL. Para estudiar los cambios morfológicos nucleares que sufren las células tras el tratamiento con los LUV-TRAIL se realizó una tinción nuclear empleando la sonda fluorescente Hoechst y se analizó mediante microscopía de fluorescencia. Se observó en ambas líneas celulares que tras el tratamiento con los LUV-TRAIL se producían los eventos característicos de la apoptosis como la condensación de la cromatina, la fragmentación del núcleo y la formación de burbujas nucleares llamadas “blebs”. Finalmente, para analizar la capacidad de los LUV-TRAIL de inducir apoptosis se analizó su capacidad de activarlas principales caspasas implicadas en la vía extrínseca de la apoptosis. Para ello, se realizó un Western Blot para ambas líneas celulares tratadas con los LUV-TRAIL para analizar la activación de la caspasa 8 y la caspasa 3, y se realizaron experimentos de citotxicidad empleando los inhibidores de caspasas ZVAD (inhibidor general de caspasas) e IETD (inhibidor específico de caspasa 8), con el objetivo de demostrar que la muerte inducida por los LUV-TRAIL en dichas líneas se produce como consecuencia de la activación de caspasas
Antibiotics in Dairy Production: Where Is the Problem?
Antibiotics have long been used for the prevention and treatment of common diseases and for prophylactic purposes in dairy animals. However, in recent decades it has become a matter of concern due to the widespread belief that there has been an abuse or misuse of these drugs in animals and that this misuse has led to the presence of residues in derived foods, such as milk and dairy products. Therefore, this review aims to compile the scientific literature published to date on the presence of antibiotic residues in these products worldwide. The focus is on the reasons that lead to their presence in food, on the potential problems caused by residues in the characteristics of dairy products and in their manufacturing process, on the development and spread of antibiotic-resistant bacteria, and on the effects that both residues and resistant bacteria can cause on human and environmental health.he research group was funded by The University of the Basque Country (UPV/EHU) (grant COLAB20/14) and by the Basque Government, grant to Research Groups number IT944-16. G. Santamarina-García received a predoctoral grant from the University of the Basque Country
Characterization of Microbial Shifts during the Production and Ripening of Raw Ewe Milk-Derived Idiazabal Cheese by High-Throughput Sequencing
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Open AccessArticle
Characterization of Microbial Shifts during the Production and Ripening of Raw Ewe Milk-Derived Idiazabal Cheese by High-Throughput Sequencing
by Gorka Santamarina-García
* [ORCID] , Igor Hernández
[ORCID] , Gustavo Amores
[ORCID] and Mailo Virto
* [ORCID]
Lactiker Research Group, Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Paseo de la Universidad 7, 01006 Vitoria-Gasteiz, Spain
*
Authors to whom correspondence should be addressed.
Academic Editor: Huizhong Chen
Biology 2022, 11(5), 769; https://doi.org/10.3390/biology11050769
Received: 13 April 2022 / Revised: 5 May 2022 / Accepted: 11 May 2022 / Published: 18 May 2022
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Simple Summary
Idiazabal is a traditional cheese produced from raw ewe milk in the Basque Country (Southwestern Europe). The sensory properties of raw milk cheeses have been attributed, among other factors, to microbial shifts that occur during the production and ripening processes. In this study, we used high-throughput sequencing technologies to investigate the microbiota of Latxa ewe raw milk and the dynamics during cheese production and ripening processes. The microbiota of raw milk was composed of lactic acid bacteria (LAB), environmental bacteria and non-desirable bacteria. Throughout the cheese making and ripening processes, the growth of LAB was promoted, whereas that of non-desirable and environmental bacteria was inhibited. Moreover, some genera not reported previously in raw ewe milk were detected and clear differences were observed in the bacterial composition of raw milk and cheese among producers, in relation to LAB and environmental or non-desirable bacteria, some of which could be attributed to the production of flavour related compounds.
Abstract
In this study, we used high-throughput sequencing technologies (sequencing of V3–V4 hypervariable regions of 16S rRNA gene) to investigate for the first time the microbiota of Latxa ewe raw milk and the bacterial shifts that occur during the production and ripening of Idiazabal cheese. Results revealed several bacterial genera not reported previously in raw ewe milk and cheese, such as Buttiauxella and Obesumbacterium. Both the cheese making and ripening processes had a significant impact on bacterial communities. Overall, the growth of lactic acid bacteria (LAB) (Lactococcus, Lactobacillus, Leuconostoc, Enterococcus, Streptococcus and Carnobacterium) was promoted, whereas that of non-desirable and environmental bacteria was inhibited (such as Pseudomonas and Clostridium). However, considerable differences were observed among producers. It is noteworthy that the starter LAB (Lactococcus) predominated up to 30 or 60 days of ripening and then, the growth of non-starter LAB (Lactobacillus, Leuconostoc, Enterococcus and Streptococcus) was promoted. Moreover, in some cases, bacteria related to the production of volatile compounds (such as Hafnia, Brevibacterium and Psychrobacter) also showed notable abundance during the first few weeks of ripening. Overall, the results of this study enhance our understanding of microbial shifts that occur during the production and ripening of a raw ewe milk-derived cheese (Idiazabal), and could indicate that the practices adopted by producers have a great impact on the microbiota and final quality of this cheese.This research was funded by the Basque Government, grant to Research Groups number IT944-16. G. Santamarina-García received a predoctoral grant from the University of the Basque Country (UPV/EHU)
Vaginal Formulations for Prevention of Sexual Transmission of HIV
According to UNAIDS, as there is still no effective vaccine against HIV, pre-exposure prophylasis (PrEP) is necessary to reduce its incidence. Sexual transmission rate is higher from men to women in developing countries and vertical transmission may also occur from mother to child. Hence, vaginal formulations are an interesting proposal for the protection of women, preventing the virus from infecting vagina through different mechanisms. Several drugs, such as Dapivirine, Tenofovir or Maraviroc, have been assessed and showed to be effective in this field. These microbicides are included in different dosage forms able to release the drug once in contact with the vaginal medium. Innovative excipients are being employed for the development of different systems trying to get an easier posology through control release and high comfortability, thus leading to a better compliance. In this line, several formulations have been developed and tested, such as rings, tablets, gels or films. Some of them are nowadays in clinical trials, such as a Tenofovir gel or a Dapivirine vaginal ring. The aim of this chapter is to synthetize the research and findings in the field of the development and assessment of vaginal formulations in the PrEP of HIV sexual transmission
Relationship between the Dynamics of Gross Composition, Free Fatty Acids and Biogenic Amines, and Microbial Shifts during the Ripening of Raw Ewe Milk-Derived Idiazabal Cheese
This study reports for the first time the relationship between bacterial succession, characterized by high-throughput sequencing (sequencing of V3–V4 16S rRNA regions), and the evolution of gross composition, free fatty acids (FFAs) and biogenic amines (BAs) during cheese ripening. Specifically, Idiazabal PDO cheese, a raw ewe milk-derived semi-hard o hard cheese, was analysed. Altogether, 8 gross parameters were monitored (pH, dry matter, protein, fat, Ca, Mg, P and NaCl) and 21 FFAs and 8 BAs were detected. The ripening time influenced the concentration of most physico-chemical parameters, whereas the producer mainly affected the gross composition and FFAs. Through an O2PLS approach, the non-starter lactic acid bacteria Lactobacillus, Enterococcus and Streptococcus were reported as positively related to the evolution of gross composition and FFAs release, while only Lactobacillus was positively related to BAs production. Several environmental or non-desirable bacteria showed negative correlations, which could indicate the negative impact of gross composition on their growth, the antimicrobial effect of FFAs and/or the metabolic use of FFAs by these genera, and their ability to degrade BAs. Nonetheless, Obesumbacterium and Chromohalobacter were positively associated with the synthesis of FFAs and BAs, respectively. This research work provides novel information that may contribute to the understanding of possible functional relationships between bacterial communities and the evolution of several cheese quality and safety parameters.This research was funded by the Basque Government, grant number IT944-16. G. Santamarina-García received a predoctoral grant from the University of the Basque Country (UPV/EHU)
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