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The ocean sampling day consortium.
Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world's oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits
AIP56, an AB toxin secreted by Photobacterium damselae subsp. piscicida, has tropism for myeloid cells
"Introduction: The AB-type toxin AIP56 is a key virulence factor of Photobacterium damselae subsp. piscicida (Phdp), inducing apoptosis in fish immune cells. The discovery of AIP56-like and AIP56-related toxins in diverse organisms, including human-associated Vibrio strains, highlights the evolutionary conservation of this toxin family, suggesting that AIP56 and its homologs may share conserved receptors across species. These toxins have potential for biotechnological applications, such as therapeutic protein delivery and immune modulation.
Methods: Herein, the cell specificity of AIP56 for immune cells was characterized. The tropism of AIP56 for cells of the sea bass, mouse and human immune system was analyzed by following toxin internalization by flow cytometry and arrival of the toxin in the cytosol by evaluating the cleavage of NF-kB p65 by western blotting.
Results: Only a small population of sea bass neutrophils internalized AIP56, indicating that most of the neutrophilic destruction during Phdp infection and/or AIP56 intoxication does not result from the direct action of the toxin. Moreover, the cellular tropism of AIP56 for myeloid cells was observed in the three species, including its preference for macrophages. Further, mouse and human M0 and M2-like macrophages internalized more toxin than M1-like macrophages. Despite the limited interaction of lymphoid cells with AIP56, mouse B1-cells were able to internalize the toxin, possibly due to its myeloid features.
Conclusion: AIP56 has tropism for sea bass, mouse and human myeloid cells, with greater affinity for macrophages. This points to an evolutionary conservation of its receptor(s) and mechanism of action across species, raising the possibility that AIP56-like and -related toxins may also play a role in pathogenesis. These findings are relevant for both pathogenicity and biomedical contexts."The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by National funds through FCT under the project UIDB/04293/2020 and by FEDER funds through Programa Operacional Factores de Competitividade – COMPETE and by national funds through FCT – Fundação para a Ciência e a Tecnologia under the project PTDC/BIA-MIC/29910/2017. AV was funded by Portuguese national funds through the FCT – Fundação para a Ciência e a Tecnologia, I.P. and, when eligible, by COMPETE 2020 FEDER funds, under the Scientific Employment Stimulus - Individual Call- 2021.02251.CEECIND/CP1663/CT0016. Inês Lua Freitas received an FCT PhD fellowship (2020.05402.BD)
Local iron homeostasis in the breast ductal carcinoma microenvironment
Abstract
BACKGROUND:
While the deregulation of iron homeostasis in breast epithelial cells is acknowledged, iron-related alterations in stromal inflammatory cells from the tumor microenvironment have not been explored.
METHODS:
Immunohistochemistry for hepcidin, ferroportin 1 (FPN1), transferrin receptor 1 (TFR1) and ferritin (FT) was performed in primary breast tissues and axillary lymph nodes in order to dissect the iron-profiles of epithelial cells, lymphocytes and macrophages. Furthermore, breast carcinoma core biopsies frozen in optimum cutting temperature (OCT) compound were subjected to imaging flow cytometry to confirm FPN1 expression in the cell types previously evaluated and determine its cellular localization.
RESULTS:
We confirm previous results by showing that breast cancer epithelial cells present an 'iron-utilization phenotype' with an increased expression of hepcidin and TFR1, and decreased expression of FT. On the other hand, lymphocytes and macrophages infiltrating primary tumors and from metastized lymph nodes display an 'iron-donor' phenotype, with increased expression of FPN1 and FT, concomitant with an activation profile reflected by a higher expression of TFR1 and hepcidin. A higher percentage of breast carcinomas, compared to control mastectomy samples, present iron accumulation in stromal inflammatory cells, suggesting that these cells may constitute an effective tissue iron reservoir. Additionally, not only the deregulated expression of iron-related proteins in epithelial cells, but also on lymphocytes and macrophages, are associated with clinicopathological markers of breast cancer poor prognosis, such as negative hormone receptor status and tumor size.
CONCLUSIONS:
The present results reinforce the importance of analyzing the tumor microenvironment in breast cancer, extending the contribution of immune cells to local iron homeostasis in the tumor microenvironment context.info:eu-repo/semantics/publishedVersio
Structural changes induced by dehydration in the crystalline layered silicate Na-RUB-18: a computational/experimental combined study
Na-RUB-18 layered silicate (Na(8)Si(32)O(64)(OH)(8) center dot 32H(2)O) is prepared following the procedure reported in the literature (ref. 1: K. Kosuge and A. Tsunashima, J. Chem. Soc., Chem. Commun., 1995, 2427) and its significant structural modifications induced by progressive removal of hydration water molecules are studied for the first time by a combined experimental (TGA and variable temperature XRD and FTIR) and theoretical approach. A novel structure of a partially de-hydrated Na-RUB-18 obtained upon heating at 75 degrees C under inert gas flow, which leads to a reversible phase transformation in agreement with XRD and FTIR results, is found. TGA indicates that at this stage, two of the four hydration water molecules per Na ion are lost. Theoretical results based on DFT calculations suggest that the apical water molecules of the solvated octahedrally coordinated sodium ion, forming weak H-bonds with the silicate oxygen atoms, are removed at this stage. As a consequence of the dehydration, the silicate layers get closer, and, similarly to that observed for zeolites, the sodium ions move towards lattice oxygen atoms, to restore their coordination shell. A combination of IR spectroscopy and computational models is used to describe the vibrational properties of silanol/silanolate (SiOH/SiO)(-1) bridges, which are responsible for the proton conduction of Na-RUB-18. The method described can be of general utility to refine structures which are not fully accessible to standard X-ray structure analysis.191726102617European CommunityRegione Piemont
Is it possible folic acid reduce anorectal malformations ethylenethiourea induced in rats?
Stroke Correlates in Chagasic and Non-Chagasic Cardiomyopathies
BACKGROUND: Aging and migration have brought changes to the epidemiology and stroke has been shown to be independently associated with Chagas disease. We studied stroke correlates in cardiomyopathy patients with focus on the chagasic etiology. METHODOLOGY/PRINCIPAL FINDINGS: We performed a cross-sectional review of medical records of 790 patients with a cardiomyopathy. Patients with chagasic (329) and non-chagasic (461) cardiomyopathies were compared. There were 108 stroke cases, significantly more frequent in the Chagas group (17.3% versus 11.1%; p<0.01). Chagasic etiology (odds ratio [OR], 1.79), pacemaker (OR, 2.49), atrial fibrillation (OR, 3.03) and coronary artery disease (OR, 1.92) were stroke predictors in a multivariable analysis of the entire cohort. In a second step, the population was split into those with or without a Chagas-related cardiomyopathy. Univariable post-stratification stroke predictors in the Chagas cohort were pacemaker (OR, 2.73), and coronary artery disease (CAD) (OR, 2.58); while atrial fibrillation (OR, 2.98), age over 55 (OR, 2.92), hypertension (OR, 2.62) and coronary artery disease (OR, 1.94) did so in the non-Chagas cohort. Chagasic stroke patients presented a very high frequency of individuals without any vascular risk factors (40.4%; OR, 4.8). In a post-stratification logistic regression model, stroke remained associated with pacemaker (OR, 2.72) and coronary artery disease (OR, 2.60) in 322 chagasic patients, and with age over 55 (OR, 2.38), atrial fibrillation (OR 3.25) and hypertension (OR 2.12; p = 0.052) in 444 non-chagasic patients. CONCLUSIONS/SIGNIFICANCE: Chagas cardiomyopathy presented both a higher frequency of stroke and an independent association with it. There was a high frequency of strokes without any vascular risk factors in the Chagas as opposed to the non-Chagas cohort. Pacemaker rhythm and CAD were independently associated with stroke in the Chagas group while age over 55 years, hypertension and atrial fibrillation did so in the non-Chagas cardiomyopathies
Production and characterization of a monoclonal antibody against an Ascaris suum allergenic component
Ascaris suum allergenic components (PIII) separated by gel filtration chromatography of an adult worm extract were used to immunize BALB/c mice. Popliteal lymph node cells taken from the immunized animals were fused with SP2/O myeloma cells using polyethylene glycol (MW 1450) as fusogen. The hybridomas were cultured in HAT-containing medium and cloned at limiting dilutions. Supernatants from the growing hybrids were screened by ELISA using plates coated with PIII or the A. suum crude extract. The monoclonal antibody obtained, named MAC-3 (mouse anti-A. suum allergenic component), is an IgG1 kappa mouse immunoglobulin that specifically recognizes a 29,000 molecular weight protein (called allergenic protein) with an affinity constant of 1.7 x 10(9) M-1. The A. suum components recognized by MAC-3 induce specific IgE antibody production in immunized BALB/c mice. Ascitic fluid induced in Swiss mice by injecting ip the hybridoma cells and incomplete Freund's adjuvant was purified by affinity chromatography using a protein A-Sepharose column. The purified monoclonal antibody was then coupled to activated Sepharose beads in order to isolate the A. suum allergenic component from the whole extract by affinity chromatography
Immunohistochemistry of the uterine cervix of rats bearing the Walker 256 tumor treated with copaiba balsam
A saúde no licenciamento ambiental: uma proposta metodológica para a avaliação dos impactos da indústria de petróleo e gás
Genetic characterization of Toxoplasma gondii isolates from eared doves (Zenaida auriculata) in Brazil
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