74 research outputs found

    Technological characterization of vaginal probiotic lactobacilli: resistance to osmotic stress and strains compatibility

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    Aims: The aim was to evaluate the osmotic stress resistance of vaginal beneficial probiotic strains, their growth kinetics and parameters when growing in salt-added culture media, and their compatibility to go further in the design of a probiotic formula for reconstitution of vaginal microbiome in women. Methods and Results: The resistance to osmotic stress of the lactobacilli was evaluated by determining their growth in MRS (as control) added with NaCl (2–8%). The most resistant strains were Lactobacillus gasseri CRL1509, L. rhamnosus CRL1332 and L. reuteri CRL1327 selected by statistical approaches and growth parameters. Electron microscopy was applied to determine changes. They maintain probiotic properties and viability. Some strains showed incompatibility, then they cannot be included in multistrain formulas. Conclusions: The resistance to different salt concentrations in vaginal lactobacilli is strain-specific, because the behaviour is different in strains identified into the same species. The resistance is not related to the metabolic groups. Significance and Impact of the Study: The resistance and survival to extreme osmotic resistance is one of the specific requirements of beneficial bacteria after the technological processes for their inclusion in probiotic formulas, in a way to express their beneficial characteristics and exert the effect on the host.Fil: Silva, Jessica Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Marchesi, Antonella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Birgitt, Wiese. Hannover Medical School; AlemaniaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

    Sequence and functional characterization of hypoxia inducible factors, HIF1α, HIF2αa, and HIF3α, from the estuarine fish, Fundulus heteroclitus

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    Author Posting. © The Author(s), 2016. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 312 (2017): R412-R425, doi:10.1152/ajpregu.00402.2016.The hypoxia inducible factor (HIF) family of transcription factors plays central roles in the development, physiology, pathology, and environmental adaptation of animals. Because many aquatic habitats are characterized by episodes of low dissolved oxygen, fish represent ideal models to study the roles of HIF in the response to aquatic hypoxia. The estuarine fish Fundulus heteroclitus occurs in habitats prone to hypoxia, it responds to low oxygen via behavioral, physiological, and molecular changes, and one member of the HIF family, HIF2α, has been previously described. Herein, cDNA sequencing, phylogenetic analyses, and genomic approaches were used to determine other members of the HIFα family from F. heteroclitus and their relationships to HIFα subunits from other vertebrates. In vitro and cellular approaches demonstrated that full-length forms of HIF1α, 2α, and 3α independently formed complexes with the β subunit (ARNT) to bind to hypoxia response elements and activate reporter gene expression. Quantitative PCR showed that HIFα mRNA abundance varied among organs of normoxic fish in an isoform-specific fashion. Analysis of the F. heteroclitus genome revealed a locus encoding a second HIF2α, HIF2αb, a predicted protein lacking oxygen sensing and transactivation domains. Finally, sequence analyses demonstrated polymorphism in the coding sequence of each F. heteroclitus HIFα subunit, suggesting that genetic variation in these transcription factors may play a role in the variation in hypoxia responses among individuals or populations.This research was supported in part by the National Science Foundation (IBN-0236494 and DEB-1120263) and by National Institute of Environmental Health Sciences (NIEHS) grant P42ES007381 (Superfund Basic Research Program at Boston University). Data interpretation was aided by reference to a preliminary draft of the F. heteroclitus genome sequence, which was supported by funding from the National Science Foundation (collaborative research grants DEB-1120512, DEB-1265282, DEB-1120013, DEB-1120263, DEB-1120333, DEB-1120398)

    First results with twisted mass fermions towards the computation of parton distribution functions on the lattice

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    We report on our exploratory study for the evaluation of the parton distribution functions from lattice QCD, based on a new method proposed in Ref.~arXiv:1305.1539. Using the example of the nucleon, we compare two different methods to compute the matrix elements needed, and investigate the application of gauge link smearing. We also present first results from a large production ensemble and discuss the future challenges related to this method.Comment: 7 pages, 4 figures, talk given at the 32nd International Symposium on Lattice Field Theory (Lattice 2014), June 23-28 2014, New York, US

    Novel inter-subunit contacts in Barley Stripe Mosaic Virus revealed by Cryo-Electron Microscopy

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    Barley stripe mosaic virus (BSMV, genus Hordeivirus) is a rod-shaped single-stranded RNA virus similar to viruses of the structurally characterized and well-studied genus Tobamovirus. Here we report the first high-resolution structure of BSMV at 4.1 Ă… obtained by cryo-electron microscopy. We discovered that BSMV forms two types of virion that differ in the number of coat protein (CP) subunits per turn and interactions between the CP subunits. While BSMV and tobacco mosaic virus CP subunits have a similar fold and interact with RNA using conserved residues, the axial contacts between the CP of these two viral groups are considerably different. BSMV CP subunits lack substantial axial contacts and are held together by a previously unobserved lateral contact formed at the virion surface via an interacting loop, which protrudes from the CP hydrophobic core to the adjacent CP subunit. These data provide an insight into diversity in structural organization of helical viruses

    Smad7 in T cells drives T helper 1 responses in multiple sclerosis and experimental autoimmune encephalomyelitis

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    Autoreactive CD4+ T lymphocytes play a vital role in the pathogenesis of multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis. Since the discovery of T helper 17 cells, there is an ongoing debate whether T helper 1, T helper 17 or both subtypes of T lymphocytes are important for the initiation of autoimmune neuroinflammation. We examined peripheral blood CD4+ cells from patients with active and stable relapsing–remitting multiple sclerosis, and used mice with conditional deletion or over-expression of the transforming growth factor-β inhibitor Smad7, to delineate the role of Smad7 in T cell differentiation and autoimmune neuroinflammation. We found that Smad7 is up-regulated in peripheral CD4+ cells from patients with multiple sclerosis during relapse but not remission, and that expression of Smad7 strongly correlates with T-bet, a transcription factor defining T helper 1 responses. Concordantly, mice with transgenic over-expression of Smad7 in T cells developed an enhanced disease course during experimental autoimmune encephalomyelitis, accompanied by elevated infiltration of inflammatory cells and T helper 1 responses in the central nervous system. On the contrary, mice with a T cell-specific deletion of Smad7 had reduced disease and central nervous system inflammation. Lack of Smad7 in T cells blunted T cell proliferation and T helper 1 responses in the periphery but left T helper 17 responses unaltered. Furthermore, frequencies of regulatory T cells were increased in the central nervous system of mice with a T cell-specific deletion and reduced in mice with a T cell-specific over-expression of Smad7. Downstream effects of transforming growth factor-β on in vitro differentiation of naïve T cells to T helper 1, T helper 17 and regulatory T cell phenotypes were enhanced in T cells lacking Smad7. Finally, Smad7 was induced during T helper 1 differentiation and inhibited during T helper 17 differentiation. Taken together, the level of Smad7 in T cells determines T helper 1 polarization and regulates inflammatory cellular responses. Since a Smad7 deletion in T cells leads to immunosuppression, Smad7 may be a potential new therapeutic target in multiple sclerosis

    Zusammenhänge zwischen Verhaltensabhängiger Elterlicher Aufmerksamkeit, Studieninteresse und Lebenszufriedenheit : Eine empirische Untersuchung an der HAW Hamburg

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    Die Anwendung Verhaltensabhängiger Elterlicher Aufmerksamkeit (VEA) in der Kindererziehung wird in diversen deutschen Erziehungsratgebern empfohlen, um das Verhalten von Kindern zu lenken. Der von Richard M. Ryan und Edward L. Deci entwickelten Selbstbestimmungstheorie (SDT) zufolge kann dieser Erziehungsstil unter Umständen zwar die erwünschten Ergebnisse erzielen, dabei sind jedoch verschiedene negative Nebeneffekte zu beobachten. Im akademischen Bereich ist dies vor allem eine Verringerung der intrinsischen Motivation und dem Interesse am Lernen selbst zugunsten eines notenfokussierten Lernens. Zudem wird das psychische Wohlbefinden aufgrund nicht befriedigter psychischer Grundbedürfnisse langfristig verringert. In der vorliegenden Arbeit wurde anhand einer Umfrage untersucht, ob bei Studierenden der HAW Hamburg ein Zusammenhang zwischen dem Erziehungsstil VEA im akademischen Bereich und dem Studieninteresse sowie der Lebenszufriedenheit nachgewiesen werden kann

    Effects of culture conditions on the growth and auto-aggregation ability of vaginal Lactobacillus johnsonii CRL 1294

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    Aims: To evaluate the effects of different physico-chemical factors on the growth and auto-aggregating ability of vaginal Lactobacillus johnsonii CRL 1294. Methods and Results: L. johnsonii CRL 1294 was cultivated in different culture media, initial pH and temperature of incubation. The growth parameters were estimated by the Gompertz model, being optimal (higher final biomass and growth rate, and shorter lag phase) at an initial pH of 6-5 and at a temperature of 37°C, both in LAPTg and MRS. The auto-aggregation ability, which was assessed by a model of exponential association, was evidenced in all the growth phases, being higher at pH 5 or 6-5. Conclusions: The growth of L. johnsonii CRL 1294 was affected in different way by all the physico-chemical factors tested. However, the auto-aggregation ability increased mainly at low initial pH of growth media. Significance and Impact of the Study: The auto-aggregation ability under different culture conditions of a vaginal Lactobacillus strain was systematically and statistically evaluated for the first time. The higher cellular aggregation evidenced at low pH could be a fundamental characteristic in the acidic vaginal environment to promote the protective role of lactobacilli.Fil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Wiese, Birgitt. Institute Of Biometry, Hannover Medical School; AlemaniaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

    Bioarchaeological research in northwestern Argentina: analyses by classification and regression trees

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    This bioarchaeological study investigates biological characteristic of human groups localised in archaeological sites in the department Belén in Northwestern Argentina. They cover a period from the Formative period till the Incas and the Spanish Conquest. To understand the variability over the time as well as the systems of interchange and the social differentiation data from 35 human skulls were analysed. The 49 discrete variables per skull represent facial features and morphological attributes. The aim was to establish relationships between individuals from the different sites or to find attributes which can discriminate between the archaeological sites. One specific problem in analysing these data was the significant percentage of missing values since some of the skulls were not complete. The method used for this analysis was CART (Classification and Regression Trees). CART can handle cases with incomplete data by identifying surrogate predictor variables. The result show a classification tree of five terminal nodes with the discriminating factors "hueso epiptérico", "foramen oval incomplete", "sutura infraorbitaria complete" and "hueso astérionico". These characteristics are known as heritabilities and do not show an ecological influence. This allow us to propose that there has been a considerable social and spatial mobility over the time in the observer area, with a longer preservation of the genotype in the communities of earlier origin and an increasing heterogeneity towards the later periods

    Survival of beneficial vaginal lactobacilli (BVL) to different gastrointestinal tract conditions

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    Background: Lactobacilli are the dominant bacteria in the healthy vaginal tract, preventing the income of pathogenic microorganisms, either sexually or not transmitted. Probiotics are used to restore the vaginal microbiome by local administration. However, the ascendant colonization is proposed as a way to restore the vaginal balance, and to exert some complementary effects on the host, situation that requires that probiotic strains resist the gastrointestinal tract passage. Objective: To determine which probiotic vaginal strains were able to resist different gastrointestinal factors (pH, bile salts, and enzymes) to advance in the design of oral formulas. Methods: Different protocols were applied to evaluate the growth of 24 beneficial vaginal lactic bacteria (BVL) strains at low pH and high bile salts (individually evaluated) and in combined protocols. The viability of the strains in simulated gastrointestinal tract conditions was studied to select the most resistant strains. Results: A low number of BVL was able to grow at low pH. Most of the strains did not survive at high bile salts concentration. The passage through pH first and bile salts later showed that only three strains were able to survive. In the simulated intestinal conditions, only Lactobacillus gasseri CRL1290, L. jensenii CRL1313, and L. jensenii CRL1349 decrease one or two logarithmic growth units (UFC/ml) at the end of the assay, maintaining their beneficial properties. Conclusion: The behavior of BVL in the conditions assayed is not related to specific strain or metabolic group, because the resistance is strain-specific. The results highlight the importance of the screening performed in a way to select the most adequate strains to be included in the oral designed formula for the restoration of the vaginal tract microbiome.Fil: Marchesi, Antonella. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Silva, Jessica Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Wiese, Birgitt. Hannover Medical School; AlemaniaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

    Physicochemical factors differentially affect the biomass and bacteriocin production by bovine Enterococcus mundtii CRL1656

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    Bovine Enterococcus mundtii CRL1656 (Centro de Referencia para Lactobacilos Culture Collection) produces an anti-Listeria and anti-Streptococcus dysgalactiae bacteriocin identified as mundticin CRL1656. The strain and its bacteriocin are candidates to be included in a beneficial product to prevent bovine mastitis as an alternative to antimicrobial agents. To optimize the production of biomass and mundticin CRL1656 by E. mundtii CRL1656, a complete 3 × 24 factorial design was applied. The effect of culture medium, initial pH, inoculum size, incubation temperature, and agitation conditions on biomass and bacteriocin production was evaluated simultaneously. Growth parameters were determined using the modified Gompertz model. A nonlinear model was used to estimate the effects of the variables on growth parameters. Bacteriocin production was analyzed using a linear mixed model. Optimal biomass and mundticin CRL1656 production by E. mundtii CRL1656 were obtained in different conditions. Maximal growth was recorded in autolyzed yeast, peptone, tryptone, Tween 80, and glucose or M17 broths, pH 6.5, 5.0% inoculum, 30°C, with agitation. However, bacteriocin titers were higher in autolyzed yeast, peptone, tryptone, Tween 80, and glucose or de Man-Rogosa-Sharpe (MRS) broths, pH 6.5, 30°C, both with or without agitation. Knowledge of the optimum conditions for growth and bacteriocin production of E. mundtii CRL1656 will allow the obtainment of high levels of biomass and mundticin CRL1656 as bioingredients of potential products to prevent bovine mastitis.Fil: Espeche, Maria Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Juárez Tomás, María Silvina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Wiese, Birgitt. Medizinische Hochschule Hannover; AlemaniaFil: Bru Chauve, Elena Magdalena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Nader, Maria Elena Fatima. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin
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