384 research outputs found
Evaluation of potential nirs to predict pastures nutritive value
This paper describes the capability of near infra-reflectance (NIRS) to predict the nutritional quality of pastures
from southern Chile (39°-40°S). A Fourier transformed near-infrared (FT-NIR) method for rapid determination
of dry matter (DM), crude protein (CP), in vitro digestibility (IVD) and metabolizable energy (ME) was used.
Calibration models were developed between chemical and NIRS spectral data using partial least squares (PLS)
regression and external validation. The coefficients of determination in calibration (R2c) were high varying between
0.89-0.99 and the root mean square errors of calibration (RMSEC) were low, ranging between 0.46-2.55 for the
parameters analysed. The Residual Prediction Deviation (RPD) was higher than 2.5. Our results confirmed the
convenience of using a wide range of samples applicability in the calibration set. Data also showed that the use of
an independent set of samples for external validation increases the robustness of the models to predict unknown
samples. Our results indicated RPD values higher than 2.5 which is the minimum recommended for this type of
prediction. Thus, the result showed that NIRS was useful to estimate the nutritional quality of permanent pastures,
and has a great potential to be used as a rapid decision tool for the studied analysis.Thanks the Fondo Nacional de Desarrollo Científico y
Tecnológico (FONDECYT) post-doc grant n°3120069.info:eu-repo/semantics/publishedVersio
The spin axes orbital alignment of both stars within the eclipsing binary system V1143Cyg using the Rossiter-McLaughlin effect
Context: The Rossiter-McLaughlin (RM) effect, a rotational effect in
eclipsing systems, provides unique insight into the relative orientation of
stellar spin axes and orbital axes of eclipsing binary systems.
Aims: Our aim is to develop a robust method to analyze the RM effect in an
eclipsing system with two nearly equally bright components. This gives access
to the orientation of the stellar rotation axes and may shed light on questions
of binary formation and evolution.
Methods: High-resolution spectra have been obtained both out of eclipse and
during the primary and secondary eclipses in the V1143Cyg system, using the
high-resolution Hamilton Echelle Spectrograph at the Lick Observatory. The
Rossiter-McLaughlin effect is analyzed in two ways: (1) by measuring the shift
of the line center of gravity during different phases of the eclipses and (2)
by analysis of the line shape change of the rotational broadening function
during eclipses.
Results: The projected axes of both stars are aligned with the orbital spin
within the observational uncertainties, with the angle of the primary rotation
axis beta_p=0.3+-1.5 deg, and the angle of the secondary rotation axis
beta_s=-1.2+-1.6 deg, thereby showing that the remaining difference between the
theoretical and observed apsidal motion for this system is not due to a
misalignment of the stellar rotation axes. Both methods utilized in this paper
work very well, even at times when the broadening profiles of the two stars
overlap.[abridged]Comment: Accepted for publication in A&A; 11 pages, 9 figures, 3 tables ; a
typo in the abstract has been correcte
In vivo induction of neutrophils chemotaxis by secretory aspartyl proteinases of Candida albicans
Secretory aspartyl proteinases (Saps) of Candida albicans are key virulence traits which cause inflammasome-dependent, aseptic inflammation in a mouse model of vaginitis. In this paper, neutrophil migration in response to Sap2, Sap6 and chemo-attractive products released from Sap-treated vaginal epithelium was measured in vitro, ex vivo and in vivo. Our results show that Sap2 and Sap6 induce neutrophil migration and production of potent chemoattractive chemokines such as IL-8 and MIP-2 by vaginal epithelial cells. Our data suggest that at least part of MIP-2 production depends upon IL-1β activity. The vaginal fluid of Candida-infected mice contained a heat-labile inhibitor of neutrophil candidacidal activity that was absent from the vaginal fluid of Sap-treated mice. Overall, our data provide additional information on the capacity of C. albicans Saps to cause aseptic vaginal inflammation and highlight the potential role of some chemokines released from vaginal epithelial cells in this phenomenon
Induction of caspase-11 by aspartyl proteinases of Candida albicans and implication in promoting inflammatory response
We recently demonstrated that the secreted aspartyl proteinases (Saps), Sap2 and Sap6, of Candida albicans have the potential to induce the canonical activation of NLRP3-inflammasome leading to the secretion of IL-1β and IL-18 via caspase-1 activation. We also observed that the activation of caspase-1 is partially independent from the NLRP3 activation pathway. In this study, we examined whether Sap2 and Sap6 are also able to activate the noncanonical inflammasome pathway in murine macrophages. Our data show that both, Sap2 and Sap6, can activate caspase-11 through type I IFN production. Caspase-11 concurs to activate caspase-1 with subsequent increase of IL-1β secretion. Endocytosis and internalization of Saps are required for the induction of type I IFN production, that is essential for induction of noncanonical inflammasome activation. Our study indicates a sophisticated interplay between caspase-1 and caspase-11 that connects canonical and noncanonical pathways of inflammasome activation in response to C. albicans Saps
The Facultative Intracellular Pathogen Candida glabrata Subverts Macrophage Cytokine Production and Phagolysosome Maturation
Human albumin enhances the pathogenic potential of Candida glabrata on vaginal epithelial cells
Funding: M.P., H.H., T.G., and B.H. received funding from the European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 642095 (OPATHY). A.K. and B. H. received support from the European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 812969 (FunHoMic). S.A. and B.H. were supported by funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 847507 (HDM-FUN). B.H. is further supported by the DFG within the Collaborative Research Centre (CRC)/Transregio (TRR) 124 “FungiNet” project C1 (DFG project number 210879364) and the Balance of the Microverse Cluster (Germany´s Excellence Strategy – EXC 2051 – Project-ID 390713860). M.S.G. was supported by the German Research Foundation (Deutsche Forschungsgemeinschaft - DFG) Emmy Noether Program (project no. 434385622 / GR 5617/1-1), and a Research Grant 2019 from the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. M.P. and H.H. received salary from grant agreement No 642095 (OPATHY) (2016-2019). A.K. received salary from grant agreement No 812969 (FunHoMic) (2019-2022).Peer reviewedPublisher PD
Expression and methylation status of tissue factor pathway inhibitor-2 gene in non-small-cell lung cancer
Tissue factor pathway inhibitor-2 (TFPI-2) is a Kunitz-type serine proteinase inhibitor that inhibits plasmin-dependent activation of several metalloproteinases. Downregulation of TFPI-2 could thus enhance the invasive potential of neoplastic cells in several cancers, including lung cancer. In this study, TFPI-2 mRNA was measured using a real-time PCR method in tumours of 59 patients with non-small-cell lung cancer (NSCLC). Tumour TFPI-2 mRNA levels appeared well correlated with protein expression evaluated by immunohistochemistry and were 4–120 times lower compared to those of nonaffected lung tissue in 22 cases (37%). Hypermethylation of the TFPI-2 gene promoter was demonstrated by restriction enzyme-polymerase chain reaction in 12 of 40 cases of NSCLC (30%), including nine of 17 for whom tumour TFPI-2 gene expression was lower than in noncancerous tissue. In contrast, this epigenetic modification was shown in only three of 23 tumours in which no decrease in TFPI-2 synthesis was found (P=0.016). Decreased TFPI-2 gene expression and hypermethylation were more frequently associated with stages III or IV NSCLC (eight out of 10, P=0.02) and the TFPI-2 gene promoter was more frequently hypermethylated in patients with lymph node metastases (eight out of 16, P=0.02). These results suggest that silencing of the TFPI-2 gene by hypermethylation might contribute to tumour progression in NSCLC
The Hyphal-Associated Adhesin and Invasin Als3 of Candida albicans Mediates Iron Acquisition from Host Ferritin
Iron sequestration by host iron-binding proteins is an important mechanism of resistance to microbial infections. Inside oral epithelial cells, iron is stored within ferritin, and is therefore not usually accessible to pathogenic microbes. We observed that the ferritin concentration within oral epithelial cells was directly related to their susceptibility to damage by the human pathogenic fungus, Candida albicans. Thus, we hypothesized that host ferritin is used as an iron source by this organism. We found that C. albicans was able to grow on agar at physiological pH with ferritin as the sole source of iron, while the baker's yeast Saccharomyces cerevisiae could not. A screen of C. albicans mutants lacking components of each of the three known iron acquisition systems revealed that only the reductive pathway is involved in iron utilization from ferritin by this fungus. Additionally, C. albicans hyphae, but not yeast cells, bound ferritin, and this binding was crucial for iron acquisition from ferritin. Transcriptional profiling of wild-type and hyphal-defective C. albicans strains suggested that the C. albicans invasin-like protein Als3 is required for ferritin binding. Hyphae of an Δals3 null mutant had a strongly reduced ability to bind ferritin and these mutant cells grew poorly on agar plates with ferritin as the sole source of iron. Heterologous expression of Als3, but not Als1 or Als5, two closely related members of the Als protein family, allowed S. cerevisiae to bind ferritin. Immunocytochemical localization of ferritin in epithelial cells infected with C. albicans showed ferritin surrounding invading hyphae of the wild-type, but not the Δals3 mutant strain. This mutant was also unable to damage epithelial cells in vitro. Therefore, C. albicans can exploit iron from ferritin via morphology dependent binding through Als3, suggesting that this single protein has multiple virulence attributes
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