A standardised approach to the biomechanical evaluation of tracheal grafts

[EN] The ideal tracheal substitute must have biomechanical properties comparable to the native trachea, but currently there is no standardised approach to evaluating these properties. Here we propose a novel method for evaluating and comparing the properties of tracheal substitutes, thus systematising both measurement and data curation. This system was tested by comparing native rabbit tracheas to frozen and decellularised specimens and determining the histological characteristics of those specimens. We performed radial compression tests on the anteroposterior tracheal axis and longitudinal axial tensile tests with the specimens anastomosed to the jaw connected to a measuring system. All calculations and results were adjusted according to tracheal size, always using variables relative to the tracheal dimensions, thus permitting comparison of different sized organs. The biomechanical properties of the decellularised specimens were only slightly reduced compared to controls and significant in regard to the maximum stress withstood in the longitudinal axis (-0.246 MPa CI [-0.248, -0.145] MPa) and the energy stored per volume unit (-0.124 mJ & BULL;mm(-3) CI [-0.195, -0.055] mJ & BULL;mm(-3)). The proposed method is suitable for the systematic characterisation of the biomechanical properties of different tracheal substitutes, regardless of the size or nature of the substitute, thus allowing for direct comparisons.This research was funded by the 2018 Spanish Society of Thoracic Surgery grant to National Multicentric Study [Number 180101 to N.J.M.-H.] and [PI16-01315 to M.M.-R.] from the Instituto de Salud Carlos III. CIBERER is funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and the Instituto de Salud Carlos III, with assistance from the European Regional Development Fund.Martínez-Hernández, NJ.; Más Estellés, J.; Milián-Medina, L.; Martínez-Ramos, C.; Cerón-Navarro, J.; Galbis-Caravajal, J.; Roig-Bataller, A.... (2021). A standardised approach to the biomechanical evaluation of tracheal grafts. Biomolecules. 11(10):1-12. https://doi.org/10.3390/biom11101461S112111

Ayotzinapa y la crisis del estado neoliberal mexicano

¿Qué pasó en Ayotzinapa? Es la pregunta que surgió el 26 de septiembre de 2014, que no encuentra una respuesta satisfactoria pese a la intervención de actores de distintas instancias, niveles y nacionalidades, y al esbozo de múltiples hipótesis sobre los enfrentamientos registrados en Iguala, Guerrero, que derivaron en la muerte de varias personas y la desaparición de 43 estudiantes de la Normal Rural “Isidro Burgos”, en una tragedia que evidenció la crisis que atraviesa el estado mexicano y que afecta a todo el país. A partir de lo acontecido en Ayotzinapa y con base en la teoría general de los campos de Pierre Bourdieu y su propuesta de análisis teórico metodológico sobre el estado, en esta obra se realiza un análisis de la práctica sistemática y generalizada de las desapariciones forzadas en México, con el fin de ofrecer otra manera de comprender el entretejido político–económico–social que hace posible este grave fenómeno, que desgarra tanto a familias como a la comunidad. La herida abierta por Ayotzinapa sangra y el objetivo último de este libro es contribuir a evitar que se cierre en tanto no se responda la interrogante de qué pasó ahí y que crímenes de lesa humanidad como este sigan aconteciendo en México.ITESO, A.C

Handmade fish meal as a partial replacement of soybean meal in diets for feedlot lambs: Effects on growth performance, dietary energy and meat quality

With the aim to evaluate a handmade fishmeal (HFM) as a partial replacement of soybean meal (SBM) in finishing diets, 36 intact male Dorper × Pelibuey lambs (41.43±7.38 kg of initial weight) were used in a completely randomized block design to test the following treatments: 1) Cracked corn-based diet containing 12% SBM, 2) inclusion of 3.5% of HFM partially replacing SBM, and 3) inclusion of 7% of HFM partially replacing SBM. Urea and limestone were utilized to balance diets in CP and calcium content. The feeding trial lasted 30 days. Replacement of SBM with HFM did not modify the effects on average daily gain (ADG) and dry matter intake (DMI), but there were numerical differences in ADG; HFM inclusion linearly improved gain-to-feed ratio; dietary net energy (NE) and observed-to-expected diet NE. Hot carcass weight and dressing percentage were not affected by HFM. Except a linear increase on C22:6, the effect of SBM replacement on fatty acid profile in meat was not significant. The meat pH registered at 24 h post-mortem linearly increased with HFM inclusion, but meat colour and sensorial values were unaffected. It was concluded that inclusion of up to 7% of HFM in diet as partial replacement of soybean meal did not negatively affect DMI and ADG, but can increase feed efficiency and dietary energy utilization. The effects of HFM on carcass and meat quality were inappreciable. Due to variations in handmade processing, it is important to verify its chemical composition before HFM can be incorporated into diets

VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro

Expression of AT1 and AT2 angiotensin receptors in astrocytomas is associated with poor prognosis

Astrocytomas develop intense vascular proliferation, essential for tumour growth and invasiveness. Angiotensin II (ANGII) was initially described as a vasoconstrictor; recent studies have shown its participation in cellular proliferation, vascularisation, and apoptosis. We conducted a prospective study to evaluate the expression of ANGII receptors – AT1 and AT2 – and their relationship with prognosis. We studied 133 tumours from patients with diagnosis of astrocytoma who underwent surgery from 1997 to 2002. AT1 and AT2 were expressed in 52 and 44% of the tumours, respectively, when determined by both reverse transcriptase–polymerase chain reaction and immunohistochemistry. Ten per cent of low-grade astrocytomas were positive for AT1, whereas grade III and IV astrocytomas were positive in 67% (P<0.001). AT2 receptors were positive in 17% of low-grade astrocytomas and in 53% of high-grade astrocytomas (P=0.01). AT1-positive tumours showed higher cellular proliferation and vascular density. Patients with AT1-positive tumours had a lower survival rate than those with AT1-negative (P<0.001). No association to survival was found for AT2 in the multivariate analysis. Expression of AT1 and AT2 is associated with high grade of malignancy, increased cellular proliferation, and angiogenesis, and is thus related to poor prognosis. These findings suggest that ANGII receptors might be potential therapeutic targets for high-grade astrocytomas

Exploring the link between MORF4L1 and risk of breast cancer.

INTRODUCTION: Proteins encoded by Fanconi anemia (FA) and/or breast cancer (BrCa) susceptibility genes cooperate in a common DNA damage repair signaling pathway. To gain deeper insight into this pathway and its influence on cancer risk, we searched for novel components through protein physical interaction screens. METHODS: Protein physical interactions were screened using the yeast two-hybrid system. Co-affinity purifications and endogenous co-immunoprecipitation assays were performed to corroborate interactions. Biochemical and functional assays in human, mouse and Caenorhabditis elegans models were carried out to characterize pathway components. Thirteen FANCD2-monoubiquitinylation-positive FA cell lines excluded for genetic defects in the downstream pathway components and 300 familial BrCa patients negative for BRCA1/2 mutations were analyzed for genetic mutations. Common genetic variants were genotyped in 9,573 BRCA1/2 mutation carriers for associations with BrCa risk. RESULTS: A previously identified co-purifying protein with PALB2 was identified, MRG15 (MORF4L1 gene). Results in human, mouse and C. elegans models delineate molecular and functional relationships with BRCA2, PALB2, RAD51 and RPA1 that suggest a role for MRG15 in the repair of DNA double-strand breaks. Mrg15-deficient murine embryonic fibroblasts showed moderate sensitivity to γ-irradiation relative to controls and reduced formation of Rad51 nuclear foci. Examination of mutants of MRG15 and BRCA2 C. elegans orthologs revealed phenocopy by accumulation of RPA-1 (human RPA1) nuclear foci and aberrant chromosomal compactions in meiotic cells. However, no alterations or mutations were identified for MRG15/MORF4L1 in unclassified FA patients and BrCa familial cases. Finally, no significant associations between common MORF4L1 variants and BrCa risk for BRCA1 or BRCA2 mutation carriers were identified: rs7164529, Ptrend = 0.45 and 0.05, P2df = 0.51 and 0.14, respectively; and rs10519219, Ptrend = 0.92 and 0.72, P2df = 0.76 and 0.07, respectively. CONCLUSIONS: While the present study expands on the role of MRG15 in the control of genomic stability, weak associations cannot be ruled out for potential low-penetrance variants at MORF4L1 and BrCa risk among BRCA2 mutation carriers.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are