Characterization of the Adherence of Clostridium difficile Spores: The Integrity of the Outermost Layer Affects Adherence Properties of Spores of the Epidemic Strain R20291 to Components of the Intestinal Mucosa

Indexación: Web of Science.Clostridium difficile is the causative agent of the most frequently reported nosocomial diarrhea worldwide. The high incidence of recurrent infection is the main clinical challenge of C. difficile infections (CBI). Formation of C. difficile spores of the epidemic strain R20291 has been shown to be essential for recurrent infection and transmission of the disease in a mouse model. However, the underlying mechanisms of how these spores persist in the colonic environment remains unclear. In this work, we characterized the adherence properties of epidemic R20291 spores to components of the intestinal mucosa, and we assessed the role of the exosporium integrity in the adherence properties by using cdeC mutant spores with a defective exosporium layer. Our results showed that spores and vegetative cells of the epidemic R20291 strain adhered at high levels to monolayers of Caco-2 cells and mucin. Transmission electron micrographs of Caco-2 cells demonstrated that the hair-like projections on the surface of R20291 spores are in close proximity with the plasma membrane and microvilli of undifferentiated and differentiated monolayers of Caco-2 cells. Competitive-binding assay in differentiated Caco-2 cells suggests that spore-adherence is mediated by specific binding sites. By using spores of a cdeC mutant we demonstrated that the integrity of the exosporium layer determines the affinity of adherence of C. difficile spores to Caco-2 cells and mucin. Binding of fibronectin and vitronectin to the spore surface was concentration-dependent, and depending on the concentration, spore-adherence to Caco-2 cells was enhanced. In the presence of an aberrantly-assembled exosporium (cdeC spores), binding of fibronectin, but not vitronectin, was increased. Notably, independent of the exosporium integrity, only a fraction of the spores had fibronectin and vitronectin molecules binding to their surface. Collectively, these results demonstrate that the integrity of the exosporium layer of strain R20291 contributes to selective spore adherence to components of the intestinal mucosa.http://journal.frontiersin.org/article/10.3389/fcimb.2016.00099/ful

Mitogenome and Nuclear-encoded Fungicide-target Genes of Thecaphora frezii - Causal Agent of Peanut Smut

Background: Thecaphora frezii Carranza and Lindquist causes smut disease in peanut (Arachis hypogaea L.) resulting in up to 35% yield losses. Fungicides have shown ineffective in controlling the disease; whereas research on the molecular basis of that fungicide resistance has been hindered because of the lack of genetic information about T. frezii. The goal of this work was to provide molecular information about fungicide-target loci in T. frezii, including its mitochondrial genome (mitogenome) and critical nuclear-encoded genes. Results: Here we report the complete annotated mitogenome of T. frezii, a 123,773 bp molecule containing the standard 14 genes that form part of mitochondrial complexes I, III, IV and V, 22 transfer RNAs, small and large subunits of ribosomal RNA, DNA polymerase, ribonuclease P, GII-reverse transcriptase/maturase, nine hypothetical open-reading frames and homing endonucleases (LAGLIDADG, GIY-YIG, HEG). In addition, we report the full-length cDNA sequence of T. frezii cytochrome b (cob) and cytochrome oxidase 1 (cox1) genes; as well as partial sequences of T. frezii succinate dehydrogenase (sdhb), ergosterol biosynthesis (Erg4), cytochrome P450 (cyp51), and beta tubulin (β-tubulin) genes, which are respective targets of strobilurins, quinone oxidation inhibitors, triazoles and beta-tubulin inhibitor fungicides commonly used in the peanut crop. Translation of cob and sdhb genes in this particular T. frezii isolate suggests potential resistance to strobilurin and carboxamide fungicides. Conclusion: The mitogenome and nuclear-encoded gene sequences presented here provide the molecular tools to research T. frezii fungicide-target loci

Discriminant analysis using fatty acids profile, stable carbon isotopes and tocopherols content as tool for feeding system prediction in Iberian pigs

Aim of study: The application of three analytical methods (fatty acids: FA, tocopherols: TOC, and isotope ratio: ISO) to distinguish the feeding type received by Iberian pigs during the fattening stage.Area of study: This distinction is very important for the labelling of Iberian high-quality products in the Quercus forest located on the southwest of Iberian Peninsula, where several production systems coexist.Material and methods: Discriminant analysis on fat samples with unknown background obtained from commercial pigs was applied. The feasibility of the combination method to determine the authentication of feeding background was studied on samples from different fattening system: free-range feeding with acorn and pastures (BE); free-range feeding acorn and pastures plus commercial feeds (RE); open-air feeding with commercial feeds (CA); standard feeding with commercial feeds (CE).Main results: In a first application of the methods, the overall success rate was 60.1% for FA, 49.7% for ISO and 49.3% for TOC. When some of the batches were reclassified attending to those previous results and additional information available about farm characteristics, ISO and TOC analyses had a 70% of success rate in the four categories, whereas FA showed 40.5%, attributable to the use of high-oleic commercial diets. The predictions improved with the method combination. The ISO+TOC combination achieved a 84.1% of success in prediction. When it was reduced to just two categories (acorn vs non-acorn), the success reached a 95% for FA+TOC and ISO+TOC.Research highlights: The use of these methods as a complementary tool for quality controls is highly recommended to avoid undesirable misclassifications

A Jerte Valley Cherry-Based Product as a Supply of Tryptophan

L-Tryptophan (tryptophan) is an essential amino acid in humans. It has important roles as a precursor of different bioactive compounds. Based on previous studies in which tryptophan has been shown to be present in fresh cherries, the aim of the present work was to analyze the tryptophan content of a Jerte Valley cherry-based product. A previously optimized method of analysis of tryptophan was used, ie, high-performance liquid chromatography with fluorescence detection (HPLC/FL). As expected, HPLC/FL technique permitted to detect and quantify the tryptophan content in a different matrix rather than fresh cherries. In fact, the Jerte Valley cherry-based product contained 69.54 ± 10.64 ppm of tryptophan, thereby showing that this product is a good source of tryptophan. In summary, it has been proven that the Jerte Valley cherry-based product is rich in tryptophan and may be indicated as a supply of this essential amino acid as well as having potential health benefits for conditions where tryptophan is necessary

Reversible Dimerization/Polymerization of a Janus Diradical Producing Labile CC Bonds and Giant Chromism

En esta comunicación se presenta el estudio espectroscópico y téorico de la dimerización/oligomerización reversible de un birradical derivado de naftoditiofeno el cual en su forma monomérica presenta una intenso color azul mientras que al agregar se muestra incoloro, siendo éstas formas intercambiables gracias a la aplicación de estímulos débiles como presión o temperatura.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Constraining very-high-energy and optical emission from FRB 121102 with the MAGIC telescopes

Fast radio bursts (FRBs) are bright flashes observed typically at GHz frequencies with millisecond duration, whose origin is likely extragalactic. Their nature remains mysterious, motivating searches for counterparts at other wavelengths. FRB 121102 is so far the only source known to repeatedly emit FRBs and is associated with a host galaxy at redshift z ≃ 0.193.We conducted simultaneous observations of FRB 121102 with the Arecibo and MAGIC telescopes during several epochs in 2016-2017. This allowed searches for millisecond time-scale burst emission in very-high-energy (VHE) gamma-rays as well as the optical band. While a total of five FRBs were detected during these observations, no VHE emission was detected, neither of a persistent nature nor burst-like associated with the FRBs. The average integral flux upper limits above 100 GeV at 95 per cent confidence level are 6.6 × 10 -12 photons cm -2 s -1 (corresponding to luminosity LVHE ≲ 10 45 erg s -1 ) over the entire observation period, and 1.2 × 10 -7 photons cm -2 s -1 (LVHE ≳ 10 49 erg s -1 ) over the total duration of the five FRBs. We constrain the optical U-band flux to be below 8.6 mJy at 5σ level for 1-ms intervals around the FRB arrival times. A bright burst with U-band flux 29 mJy and duration ~12 ms was detected 4.3 s before the arrival of one FRB. However, the probability of spuriously detecting such a signal within the sampled time space is 1.5 per cent (2.2, post-trial), i.e. consistent with the expected background. We discuss the implications of the obtained upper limits for constraining FRB models

Efecto del hongo entomopatógeno Beauveria bassiana en el control de garrapatosis en ganado bovino

This study was carried out to determine the effect of the entomopathogenic fungus Beauveria bassiana on the control of ticks in cattle. In total, 20 Fleckvieh female cattle were distributed in five treatments: T1 = control group, T2 = excipients (water + 0.6 ml of surfactant), T3 = 1.2x107 conidia (80 g of fungus + 0.2 ml surfactant), T4 = 2.4 x107 conidia (160 g of fungus + 0.4 ml of surfactant), T5 = 3.6x107 conidia (240 g of fungus + 0.6 ml of surfactant). The fungus was washed with water and surfactant to detach them from the substrate and then applied to the cattle by thick-drop spraying. The tick count was performed in six areas (neck table, groin, armpit) on days 0 (before treatment), 1, 2, 3, 5, 7, 9, 11 and 14. The significant decrease in the number of ticks were observed from day 7 on T3, T4, T5. The decrease in ticks on day 14 was 99% in T5, while in T3 and T4 it was 91 and 82%, respectively.La investigación fue realizada para determinar el efecto del hongo entomopatógeno Beauveria bassiana en el control de garrapatas en ganado bovino. Se trabajó con 20 bovinos hembra de raza Fleckvieh distribuidos en cinco tratamientos: T1= grupo control, T2= excipientes (agua + 0.6 ml de surfactante), T3= 1.2x107 conidias (80 g de hongo + 0.2 ml surfactante), T4= 2.4x107 conidias (160 g de hongo + 0.4 ml de surfactante), T5 = 3.6x107 conidias (240 g de hongo + 0.6 ml de surfactante). El hongo fue lavado con agua y surfactante, con el fin de desprenderlas del sustrato para luego ser aplicado a los bovinos por medio de aspersión por gota gruesa. El conteo de garrapatas se realizó en seis zonas (tabla del cuello, entrepierna, axila) los días 0 (antes del tratamiento), 1, 2, 3, 5, 7, 9, 11 y 14. La disminución significativa en el número de garrapatas se observó a partir del día 7 en T3, T4, T5. La disminución de garrapatas en el día 14 fue de 99% en T5, mientras que en T3 y T4 fue de 91 y 82%, respectivamente

Diagnostic accuracy of ultrasound signs for detecting adnexal torsion: systematic review and meta-analysis

Objective: To evaluate the diagnostic accuracy of different ultrasound signs for diagnosing adnexal torsion, using surgery as the reference standard. Methods: This was a systematic review and meta-analysis of studies published between January 1990 and November 2021 evaluating ovarian edema, adnexal mass, ovarian Doppler flow findings, the whirlpool sign and pelvic fluid as ultrasound signs (index tests) for detecting adnexal torsion, using surgical findings as the reference standard. The search for studies was performed in PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov and Web of Science databases. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was used to evaluate the quality of the studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios were calculated separately, and the post-test probability of adnexal torsion following a positive or negative test was also determined. Results: The search identified 1267 citations after excluding duplicates. Eighteen studies were ultimately included in the qualitative and quantitative syntheses. Eight studies (809 patients) analyzed the presence of ovarian edema, eight studies (1044 patients) analyzed the presence of an adnexal mass, 14 studies (1742 patients) analyzed ovarian Doppler flow, six studies (545 patients) analyzed the whirlpool sign and seven studies (981 patients) analyzed the presence of pelvic fluid as ultrasound signs of adnexal torsion. Overall, the quality of most studies was considered to be moderate or good. However, there was a high risk of bias in the patient-selection and index-text domains (with the exception of the whirlpool sign) in a significant proportion of studies. Pooled sensitivity, specificity, and positive and negative likelihood ratios of each ultrasound sign were 58%, 86%, 4.0 and 0.49 for ovarian edema, 69%, 46%, 1.3 and 0.67 for adnexal mass, 65%, 91%, 7.6 and 0.38 for the whirlpool sign, 53%, 95%, 11.0 and 0.49 for ovarian Doppler findings and 55%, 69%, 1.7 and 0.66 for pelvic fluid. Heterogeneity was high for all analyses. Conclusions: The presence of an adnexal mass or pelvic fluid have poor diagnostic accuracy as ultrasound signs of adnexal torsion, while the presence of ovarian edema, the whirlpool sign and decreased or absent ovarian Doppler flow have good specificity but moderate sensitivity for detecting adnexal torsion. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.Objetivo.Evaluar la precision diagnostica de diferentes indicios ecograficos para el diagnostico de la torsion anexial,utilizando la cirugia como patron de referencia. Metodos. Se trata de una revision sistematica y un metaanalisis de los estudios publicados entre enero de 1990 y noviembre de 2021 que evaluaron el edema ovarico, la masa anexial, los resultados del flujo Doppler ovarico, el ‘‘signo del remolino’’ (torsion ovarica) y el liquido pelvico como indicios ecograficos (pruebas de referencia) para detectar la torsion anexial, utilizando los resultados quirurgicos como patron de referencia. La busqueda de estudios se realizo en las bases de datos PubMed/MEDLINE, CINAHL, Scopus, The Cochrane Library, ClinicalTrials.gov y Web of Science.Para evaluar la calidad de los estudios se utilizo la herramienta de Evaluacion de Calidad de los Estudios de Precision Diagnostica-2 (QUADAS-2, por sus siglas en ingles). Se calcularon por separado los valores combinados de sensibilidad,especificidad y cocientes de verosimilitud positivos y negativos, y se determino tambien la probabilidad posterior a la prueba de la torsion anexial tras una prueba positiva o negativa. Resultados. La busqueda identifico 1267 citas, una vez excluidas las duplicadas. Se incluyeron dieciocho estudios en las sıntesis cualitativa y cuantitativa. Ocho estudios (809 pacientes) analizaron la presencia de edema ovarico, ocho estudios(1044 pacientes) analizaron la presencia de una masa anexial, 14 estudios (1742 pacientes) analizaron el flujo Doppler ovarico, seis estudios (545 pacientes) analizaron el ‘‘signo del remolino’’ y siete estudios (981 pacientes) analizaron la presencia de lıquido pelvico como indicios ecograficos de torsion anexial. En general, la calidad de la mayorıa de los estudios se considero moderada o buena. Sin embargo, hubo un alto riesgo de sesgo en una proporcion significativa de estudios en las areas de seleccion de pacientes y texto de referencia (con la excepcion del ‘‘signo del remolino’’). Los valores combinados de la sensibilidad, la especificidad y los cocientes de probabilidad positivos y negativos de cada indicio ecografico fueron del 58%, 86%, 4,0 y 0,49 para el edema ovarico, del 69%, 46%, 1,3 y 0,67 para la masa anexial, del 65%, 91%, 7,6 y 0,38 para el ‘‘signo del remolino’’, del 53%, 95%, 11,0 y 0,49 para los resultados del Doppler ovarico y del 55%, 69%, 1,7 y 0,66 para el liquido pelvico. La heterogeneidad fue elevada en todos los analisis. Conclusion. La presencia de una masa anexial o de liquido pelvico apenas tienen precision diagnostica como indicios ecograficos de torsion anexial, mientras que la presencia de edema ovarico, el ‘‘signo del remolino’’ y la disminucion o ausencia de flujo Doppler ovarico tienen una buena especificidad, pero una sensibilidad moderada para detectar la torsion anexial

The Gluonic Field of a Heavy Quark in Conformal Field Theories at Strong Coupling

We determine the gluonic field configuration sourced by a heavy quark undergoing arbitrary motion in N=4 super-Yang-Mills at strong coupling and large number of colors. More specifically, we compute the expectation value of the operator tr[F^2+...] in the presence of such a quark, by means of the AdS/CFT correspondence. Our results for this observable show that signals propagate without temporal broadening, just as was found for the expectation value of the energy density in recent work by Hatta et al. We attempt to shed some additional light on the origin of this feature, and propose a different interpretation for its physical significance. As an application of our general results, we examine when the quark undergoes oscillatory motion, uniform circular motion, and uniform acceleration. Via the AdS/CFT correspondence, all of our results are pertinent to any conformal field theory in 3+1 dimensions with a dual gravity formulation.Comment: 1+38 pages, 16 eps figures; v2: completed affiliation; v3: corrected typo, version to appear in JHE

Advancing in Schaaf-Yang syndrome pathophysiology: from bedside to subcellular analyses of truncated MAGEL2

Background Schaaf-Yang syndrome (SYS) is caused by truncating mutations in MAGEL2, mapping to the Prader-Willi region (15q11-q13), with an observed phenotype partially overlapping that of Prader-Willi syndrome. MAGEL2 plays a role in retrograde transport and protein recycling regulation. Our aim is to contribute to the characterisation of SYS pathophysiology at clinical, genetic and molecular levels. Methods We performed an extensive phenotypic and mutational revision of previously reported patients with SYS. We analysed the secretion levels of amyloid-β 1-40 peptide (Aβ1-40) and performed targeted metabolomic and transcriptomic profiles in fibroblasts of patients with SYS (n=7) compared with controls (n=11). We also transfected cell lines with vectors encoding wild- type (WT) or mutated MAGEL2 to assess stability and subcellular localisation of the truncated protein. Results Functional studies show significantly decreased levels of secreted Aβ1-40 and intracellular glutamine in SYS fibroblasts compared with WT. We also identified 132 differentially expressed genes, including non-coding RNAs (ncRNAs) such as HOTAIR, and many of them related to developmental processes and mitotic mechanisms. The truncated form of MAGEL2 displayed a stability similar to the WT but it was significantly switched to the nucleus, compared with a mainly cytoplasmic distribution of the WT MAGEL2. Based on the updated knowledge, we offer guidelines for the clinical management of patients with SYS. Conclusion A truncated MAGEL2 protein is stable and localises mainly in the nucleus, where it might exert a pathogenic neomorphic effect. Aβ1-40 secretion levels and HOTAIR mRNA levels might be promising biomarkers for SYS. Our findings may improve SYS understanding and clinical management