Skin-associated lactic acid bacteria from North American bullfrogs as potential control agents of batrachochytrium dendrobatidis

The fungal pathogen Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis and has been a key driver in the catastrophic decline of amphibians globally. While many strategies have been proposed to mitigate Bd outbreaks, few have been successful. In recent years, the use of probiotic formulations that protect an amphibian host by killing or inhibiting Bd have shown promise as an effective chytridiomycosis control strategy. The North American bullfrog (Lithobates catesbeianus) is a common carrier of Bd and harbours a diverse skin microbiota that includes lactic acid bacteria (LAB), a microbial group containing species classified as safe and conferring host benefits. We investigated beneficial/probiotic properties: anti-Bd activity, and adhesion and colonisation characteristics (hydrophobicity, biofilm formation and exopolysaccharide-EPS production) in two confirmed LAB (cLAB-Enterococcus gallinarum CRL 1826, Lactococcus garvieae CRL 1828) and 60 presumptive LAB (pLAB) [together named as LABs] isolated from bullfrog skin.We challenged LABs against eight genetically diverse Bd isolates and found that 32% of the LABs inhibited at least one Bd isolate with varying rates of inhibition. Thus, we established a score of sensitivity from highest (BdGPL AVS7) to lowest (BdGPL C2A) for the studied Bd isolates. We further reveal key factors underlying host adhesion and colonisation of LABs. Specifically, 90.3% of LABs exhibited hydrophilic properties that may promote adhesion to the cutaneous mucus, with the remaining isolates (9.7%) being hydrophobic in nature with a surface polarity compatible with colonisation of acidic, basic or both substrate types. We also found that 59.7% of LABs showed EPS synthesis and 66.1% produced biofilm at different levels: 21% weak, 29% moderate, and 16.1% strong. Together all these properties enhance colonisation of the host surface (mucus or epithelial cells) and may confer protective benefits against Bd through competitive exclusion. Correspondence analysis indicated that biofilm synthesis was LABs specific with high aggregating bacteria correlating with strong biofilm producers, and EPS producers being correlated to negative biofilm producing LABs. We performed Random Amplified Polymorphic DNA (RAPD)-PCR analysis and demonstrated a higher degree of genetic diversity among rod-shaped pLAB than cocci. Based on the LAB genetic analysis and specific probiotic selection criteria that involve beneficial properties, we sequenced 16 pLAB which were identified as Pediococcus pentosaceus, Enterococcus thailandicus, Lactobacillus pentosus/L. plantarum, L. brevis, and L. curvatus. Compatibility assays performed with cLAB and the 16 species described above indicate that all tested LAB can be included in a mixed probiotic formula. Based on our analyses, we suggest that E. gallinarum CRL 1826, L. garvieae CRL 1828, and P. pentosaceus 15 and 18B represent optimal probiotic candidates for Bd control and mitigation. © 2019 Niederle et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited149FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2016/25358-3This research was supported by Consejo Nacional de Investigaciones Científicas y Técnicas (PIP 063 to SEP), Consejo de Investigaciones de la Universidad Nacional de Tucumán (PIUNT 26/D 414 and 26/D 645 to SEP, and PIUNT 528), Agencia Nacional de Promoción Científica y Tecnológica (PICT 2017-2244 to SEP, PICT 2015-2467 to CEA, and PICT2017-4324 to MENM), Ministerio de Economía y Competitividad de España (CGL2015-70070-R to JB), Fondo Nacional de Desarrollo Científico y Tecnológico (1181758 to CSA and 3180107 to AVS), Fundação de Amparo à Pesquisa do Estado de São Paulo (2016/25358-3 to LFT). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscrip

Serrated polyp detection and risk of interval post-colonoscopy colorectal cancer: a population-based study

Background Adenoma detection rate (ADR) is a well-established quality indicator for colonoscopy and is inversely associated with the incidence of interval post-colonoscopy colorectal cancer. However, interval post-colonoscopy colorectal cancers frequently develop from serrated polyps, which are not included in the ADR. Therefore, the proximal serrated polyp detection rate (PSPDR) has been proposed as a quality indicator, but its association with interval post-colonoscopy colorectal cancer has not been studied. We aimed to evaluate this potential association based on data collected in the Dutch colorectal cancer screening programme. Methods In this population-based study, using colonoscopy data from the Dutch faecal immunochemical test-based colorectal cancer screening programme and cancer data from the Netherlands Cancer Registry, we evaluated the association between endoscopists' individual PSPDR and their patients' risk of interval post-colonoscopy colorectal cancer with a shared frailty Cox proportional-hazard regression analysis. Participants in the screening programme who were eligible for inclusion were aged 55-76 years, had a positive faecal immunochemical test (cutoff 15 mu g Hb/g faeces at start and changed mid-2014 to 47 mu g Hb/g faeces), were asymptomatic, and underwent a colonoscopy between Jan 1, 2014, and Dec 31, 2020. The PSPDR was defined as the proportion of colonoscopies in which at least one serrated polyp proximal to the descending colon was detected, confirmed by histopathology. The ADR was defined as the proportion of all colonoscopies in which at least one conventional adenoma was detected, confirmed by histopathology. Detection rates were determined for each endoscopist individually. We additionally evaluated the risk of interval post-colonoscopy colorectal cancer for endoscopists with a PSPDR and ADR above the median versus endoscopists with either one or both parameters below the median. This study is registered with the Netherlands Trial Registry, NL8350. Findings During the study period, 329 104 colonoscopies were done, of which 277 555, done by 441 endoscopists, were included in the PSPDR calculations. The median PSPDR was 11.9% (IQR 8.3-15.8) and median ADR was 66.3% (61.4-69.9). The correlation between the PSDPR and ADR was moderate (r=0.59; p < 0middot0001). During a median follow-up of 33 months (IQR 21-42), 305 interval post-colonoscopy colorectal cancers were detected. For each percentage point increase in PSPDR, the adjusted interval post-colonoscopy colorectal cancer hazard was 7% lower (hazard ratio [HR] 0.93, 95% CI 0.90-0.95; p < 0middot0001). Compared with endoscopists with a PSPDR greater than 11middot9% and ADR greater than 66middot3%, the HR of interval post-colonoscopy colorectal cancer for endoscopists with a low PSPDR and high ADR was 1.79 (95% CI 1.22-2.63), for endoscopists with a high PSPDR and low ADR was 1.97 (1.19-3.24), and for endoscopists with a low PSPDR and low ADR was 2.55 (1.89-3.45). Gastroenterology, (Prof Gastroenterology the (Prof Interpretation The PSPDR of an endoscopist is inversely associated with the incidence of interval post-colonoscopy colorectal cancer. Implementation of PSPDR monitoring, in addition to ADR monitoring, could optimise colorectal cancer prevention. Copyright (C) 2022 Elsevier Ltd. All rights reserved.Cellular mechanisms in basic and clinical gastroenterology and hepatolog

Acciones implementadas para promover la donación voluntaria de sangre

La donación de sangre es un pilar fundamental para el mejoramiento de la salud pública. Por esto, la donación voluntaria se considera como uno de los medios más adecuados para proveer la sangre necesaria para los bancos de sangre públicos. En la Argentina, el sistema predominante para cumplir con el requerimiento de sangre para las personas que la necesitan es la donación por reposición (90%). Sin embargo, el mundo avanza hacia un nuevo paradigma: la donación habitual, voluntaria y solidaria de sangre. En este sentido, el grupo VIDAS (Voluntarios Interconectados por la Donación Altruista de Sangre) formado por alumnos, docentes, graduados, personal administrativo y de servicios de la Universidad Nacional de Quilmes (UNQ) y miembros de la comunidad, busca realizar acciones para contribuir a la solución de la problemática de la donación de sangre en la Argentina. Este trabajo, muestra las acciones que se están realizando desde el proyecto de Extensión Universitaria: “Donación Voluntaria de Sangre: Formación, Difusión y Organización de campañas de donación“. Estas acciones abarcan tres líneas principales: (1) Organización de campañas de donación de sangre; (2) Difusión y concientización, y (3) Formación de promotores de la donación voluntaria de sangre. Hasta el momento se organizaron seis campañas de donación de sangre (colectas externas) en la UNQ con el Hospital Garrahan, con el fin de incrementar el número de donaciones voluntarias de manera directa. Mediante encuestas, se detectó que más del 50% de los donantes en las colectas, lo son por primera vez; así como también se logró la fidelización de muchos otros. Durante las colectas, se focaliza en la difusión de información a la población en general, con el fin de concientizar y educar en los temas referentes a la donación de sangre. Además, periódicamente se realizan publicaciones en redes sociales y medios de comunicación de la zona de influencia (radio, TV y diarios). En colaboración con el Hospital Garrahan se dictaron tres cursos de formación de promotores, formándose grupos de personas con conocimiento de la problemática y capaces de difundir un mensaje claro, respetando las líneas del Plan Nacional de Sangre. Si bien la zona de influencia esta focalizada en los alrededores de la UNQ y a la población de la misma, el efecto es claramente multiplicador hacia la sociedad entera. A futuro, se contempla extender y replicar esta experiencia en otras regiones y/o instituciones, haciendo foco en la difusión y en la promoción.

The First Millennium-Age Araucaria Araucana in Patagonia

This item is part of the Tree-Ring Research (formerly Tree-Ring Bulletin) archive. For more information about this peer-reviewed scholarly journal, please email the Editor of Tree-Ring Research at [email protected]

Anisotropic flow of charged hadrons, pions and (anti-)protons measured at high transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}=2.76 TeV

The elliptic, $v_2$, triangular, $v_3$, and quadrangular, $v_4$, azimuthal anisotropic flow coefficients are measured for unidentified charged particles, pions and (anti-)protons in Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. Results obtained with the event plane and four-particle cumulant methods are reported for the pseudo-rapidity range $|\eta|<0.8$ at different collision centralities and as a function of transverse momentum, $p_{\rm T}$, out to $p_{\rm T}=20$ GeV/$c$. The observed non-zero elliptic and triangular flow depends only weakly on transverse momentum for $p_{\rm T}>8$ GeV/$c$. The small $p_{\rm T}$ dependence of the difference between elliptic flow results obtained from the event plane and four-particle cumulant methods suggests a common origin of flow fluctuations up to $p_{\rm T}=8$ GeV/$c$. The magnitude of the (anti-)proton elliptic and triangular flow is larger than that of pions out to at least $p_{\rm T}=8$ GeV/$c$ indicating that the particle type dependence persists out to high $p_{\rm T}$.Comment: 16 pages, 5 captioned figures, authors from page 11, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/186

Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm{NN}}} = 2.76 TeV

The inclusive transverse momentum ($p_{\rm T}$) distributions of primary charged particles are measured in the pseudo-rapidity range $|\eta|<0.8$ as a function of event centrality in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=2.76$ TeV with ALICE at the LHC. The data are presented in the $p_{\rm T}$ range $0.15<p_{\rm T}<50$ GeV/$c$ for nine centrality intervals from 70-80% to 0-5%. The Pb-Pb spectra are presented in terms of the nuclear modification factor $R_{\rm{AA}}$ using a pp reference spectrum measured at the same collision energy. We observe that the suppression of high-$p_{\rm T}$ particles strongly depends on event centrality. In central collisions (0-5%) the yield is most suppressed with $R_{\rm{AA}}\approx0.13$ at $p_{\rm T}=6$-7 GeV/$c$. Above $p_{\rm T}=7$ GeV/$c$, there is a significant rise in the nuclear modification factor, which reaches $R_{\rm{AA}} \approx0.4$ for $p_{\rm T}>30$ GeV/$c$. In peripheral collisions (70-80%), the suppression is weaker with $R_{\rm{AA}} \approx 0.7$ almost independently of $p_{\rm T}$. The measured nuclear modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/284

Measurement of charm production at central rapidity in proton-proton collisions at s=2.76\sqrt{s} = 2.76 TeV

The $p_{\rm T}$-differential production cross sections of the prompt (B feed-down subtracted) charmed mesons D$^0$, D$^+$, and D$^{*+}$ in the rapidity range $|y|<0.5$, and for transverse momentum $1< p_{\rm T} <12$ GeV/$c$, were measured in proton-proton collisions at $\sqrt{s} = 2.76$ TeV with the ALICE detector at the Large Hadron Collider. The analysis exploited the hadronic decays D$^0 \rightarrow$K$\pi$, D$^+ \rightarrow$K$\pi\pi$, D$^{*+} \rightarrow$D$^0\pi$, and their charge conjugates, and was performed on a $L_{\rm int} = 1.1$ nb$^{-1}$ event sample collected in 2011 with a minimum-bias trigger. The total charm production cross section at $\sqrt{s} = 2.76$ TeV and at 7 TeV was evaluated by extrapolating to the full phase space the $p_{\rm T}$-differential production cross sections at $\sqrt{s} = 2.76$ TeV and our previous measurements at $\sqrt{s} = 7$ TeV. The results were compared to existing measurements and to perturbative-QCD calculations. The fraction of cdbar D mesons produced in a vector state was also determined.Comment: 20 pages, 5 captioned figures, 4 tables, authors from page 15, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/307

Particle-yield modification in jet-like azimuthal di-hadron correlations in Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV

The yield of charged particles associated with high-$p_{\rm T}$ trigger particles ($8 < p_{\rm T} < 15$ GeV/$c$) is measured with the ALICE detector in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jet-like correlation peaks in azimuthal di-hadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta $p_{\rm T}> 3$ GeV/$c$ on the away-side drops to about 60% of that observed in pp collisions, while on the near-side a moderate enhancement of 20-30% is found.Comment: 15 pages, 2 captioned figures, 1 table, authors from page 10, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/350

Reconocimiento de diásporas de Malveae (Malvaceae) en muestras de suelos de zonas serranas (Sierras Chicas, Córdoba, Argentina) afectadas por incendios

En el marco de un estudio de regeneración post-incendio de la vegetación autóctona en campos de sierra ubicados en proximidades de Falda del Carmen (Sierras Chicas, Córdoba, Argentina), se ha analizado el banco de semillas aéreo para facilitar la identificación de las especies presentes en las muestras de suelo. Entre las familias con mayor diversidad y abundancia en la zona evaluada, las Malvaceae se encuentran representadas por 14 especies pertenecientes a los géneros: Abutilon Mill., Gaya Kunth., Krapovickasia Fryxell, Malvastrum A. Gray, Pavonia Cav., Pseudabutilon R. E. Fr., Sida L. y Sphaeralcea A. St.-Hil.. Se presentan dos claves dicotómicas para diferenciar las especies utilizando caracteres morfológicos de las diásporas, mericarpos y semillas respectivamente, acompañadas por las descripciones y las ilustraciones de las estructuras consideradas. Se tienen en cuenta aspectos morfológicos de los mericarpos (forma, tamaño, superficie de las caras dorsal y laterales, dehiscencia, aristas, pubescencia, divisiones internas, número de semillas por mericarpo) y de las semillas (forma, tamaño, superficie, pubescencia, hilo)