The ERECTA Receptor-Like Kinase Regulates Cell Wall-Mediated Resistance to Pathogens in Arabidopsis thaliana.

Some receptor-like kinases (RLK) control plant development while others regulate immunity. The Arabidopsis ERECTA (ER) RLK regulates both biological processes. To discover specific components of ER-mediated immunity, a genetic screen was conducted to identify suppressors of erecta (ser) susceptibility to Plectosphaerella cucumerina fungus. The ser1 and ser2 mutations restored disease resistance to this pathogen to wild-type levels in the er-1 background but failed to suppress er-associated developmental phenotypes. The deposition of callose upon P. cucumerina inoculation, which was impaired in the er-1 plants, was also restored to near wild-type levels in the ser er-1 mutants. Analyses of er cell walls revealed that total neutral sugars were reduced and uronic acids increased relative to those of wild-type walls. Interestingly, in the ser er-1 walls, neutral sugars were elevated and uronic acids were reduced relative to both er-1 and wild-type plants. The cell-wall changes found in er-1 and the ser er-1 mutants are unlikely to contribute to their developmental alterations. However, they may influence disease resistance, as a positive correlation was found between uronic acids content and resistance to P. cucumerina. We propose a specific function for ER in regulating cell wall-mediated disease resistance that is distinct from its role in development.

Lengua negra pilosa asociada a carcinoma escamocelular de esófago / Black hairy tongue associated with squamous cell carcinoma of the esophagus

Resumen La lengua negra pilosa (LNP) es una alteración benigna caracterizada por coloración oscura e hipertrofia con hiperqueratosis en las papilas filiformes de la superficie de la lengua. Han sido implicados varios factores intrínsecos y extrínsecos como causales, entre ellos la pobre higiene dental, el tabaquismo, la ingesta de bebidas oscuras, el uso de antibióticos y algunas patologías malignas. Reportamos el caso de un paciente con carcinoma escamocelular avanzado de esófago medio conjunto con LNP, asociación no encontrada previamente en la literatura.

Abstract Black hairy tongue (BHT) is a benign disorder characterized by dark coloration and hypertrophy with hyperkeratosis in filiform papillae on the surface of the tongue. Several intrinsic and extrinsic factors, including poor dental hygiene, smoking, drinking dark beverages, indiscriminate use of antibiotics, and some malignant diseases, have been proposed as potential causes. This is the case of a patient with advanced squamous cell carcinoma of the mid esophagus in conjunction with BHT, a previously unknown association.

Cohortes de premedicación en endoscopia alta con simeticona, N-acetilcisteína, Hedera helix y validación de la escala visual / Cohorts of premedication for endoscopy of the upper gastrointestinal tract with simethicone, N-acetylcysteine, Hedera helix and visual scale validation

Resumen Los parámetros de calidad para endoscopia digestiva alta han introducido indicadores intraprocedimiento, dentro de los cuales la adecuada visibilidad de la mucosa, libre de saliva, moco o burbujas, puede aumentar la posibilidad de detección de lesiones en fase temprana. Sin embargo, el uso de mucolíticos y antiburbujas ha mostrado gran variabilidad de eficiencia según las soluciones, concentraciones, tiempos de exposición y escala de visibilidad aplicados. Objetivos: determinar la efectividad de diferentes soluciones de premedicación para la limpieza de la mucosa digestiva; validar, mediante una prueba de concordancia interobservador, una nueva escala de adecuada visualización de la mucosa (TVMS) para el esófago, estómago y duodeno; y reportar eventos adversos o complicaciones relacionadas con las soluciones utilizadas y los procedimientos realizados. Material y métodos: estudio de cohortes prospectivas comparativas. Se incluyeron 412 pacientes adultos, ASA I y ASA II, para endoscopia diagnóstica bajo sedación consciente, distribuidos en 6 cohortes similares, divididas en dos grupos: no premedicación, 2 cohortes C1 (ayuno de 6 a 8 horas)y C2 (agua 100 mL); premedicación, 4 cohortes C3 a C6 (C3: agua 100 m L + simeticona 1000 mg; C4: agua 100 mL + simeticona 200 mg + N-acetilcisteína 600 mg; C5: agua 100 mL + simeticona 200 mg + N-acetilcisteína 1000 mg; C6: agua 100 mL + simeticona 200 mg + Hedera helix 70 mg). Se ingirió la solución 15 a 30 minutos antes del paso por cricofaríngeo. Se realizó la prueba de Kappa para medir la concordancia interobservador de la escala TVMS. Resultados: De 412 pacientes, 58% fueron de sexo femenino; 23% (136) fue de cohortes C1 y C2 y 67% (276) fue de cohortes C3 a C6. El tiempo medio de exposición a cada solución fue de 24,4 minutos. El volumen de lavado para lograr una adecuada visualización fue significativamente diferente entre ambos grupos: en los pacientes con premedicación se utilizaron 75,6 mL, mientras que en los pacientes sin premedicación se utilizaron 124 mL (p = 0,000), con una calidad de TVMS excelente de 88,7% frente al 41,4%, respectivamente. La cohorte C4 (agua 100 mL + simeticona 200 mg + N-acetilcisteína 600 mg) mostró ser la más efectiva con una diferencia significativa (p = 0,001) frente a C1 (ayuno) y C2 (placebo con agua 100 mL), y también tuvo una eficiencia superior frente a C3, C5 y C6 en su orden. No se presentaron eventos adversos o complicaciones en relación con la endoscopia, la sedación y los productos usados en la premedicación. Conclusiones: la solución más efectiva como premedicación para lograr una excelente visibilidad de la mucosa digestiva correspondió a la cohorte C4 (SIM 200 + NAC 600 + H2O 100 mL). La escala TVMS propuesta es una herramienta muy completa y fácil de aplicar por más de un observador. La premedicación ingerida, con antiburbuja, mucolítico y agua hasta 100 mL, entre 15 y 30 minutos previos a endoscopia, es segura en las condiciones descritas en este estudio.

Abstract Quality parameters for upper gastrointestinal endoscopy have introduced intraprocedural indicators, including adequate mucosal visualization free of saliva, mucus, or bubbles, which may increase the possibility of early-stage injury detection. The use of mucolytics and anti-foaming agents has shown great efficiency variability depending on the type of solution, concentrations, exposure times and visibility scale applied. Objectives: To determine the effectiveness of different premedication solutions for cleaning the digestive mucosa; to validate, by means of an interobserver concordance test, a new scale for the adequate visualization of the mucosa (TVMS) for the esophagus, stomach, and duodenum; and to report adverse events or complications associated with the solutions used and the procedures performed. Material and methods: Prospective, comparative cohort study. 412 adult patients, ASA I and ASA II, were included for diagnostic endoscopy under conscious sedation. They were distributed in 6 similar cohorts and divided into two groups: non-premedication, 2 in C1 (fasting 6 to 8 hours) and C2 (water 100 mL) cohorts; premedication, 4 C3 to C6 cohorts (C3: water 100 mL + simethicone 1000 mg; C4: water 100 ml + simethicone 200 mg + N-acetylcysteine 600 mg; C5: water 100 ml + simethicone 200 mg + N-acetylcysteine 1000 mg; C6: water 100 ml + simethicone 200 mg + Hedera helix 70 mg). The solution was swallowed 15 to 30 minutes passing through the cricopharyngeus muscle. The Kappa test was performed to measure interobserver concordance of the TVMS scale. Results: Of 412 patients, 58% were female; 23% (136) were included in the C1 and C2 cohorts; and 67% (276) were in the C3 to C6 cohorts. The average exposure time to each solution was 24.4 minutes. The wash volume for proper visualization was significantly different between the two groups. In premedicated patients, 75.6 mL of solution were used, while in patients without premedication, 124 mL were used (p = 0.000), with an excellent quality of TVMS of 88.7% versus 41.4%, respectively. The C4 cohort (water 100 mL + simethicone 200 mg + N-acetylcysteine 600 mg) was the most effective with a significant difference (p= 0.001) compared with the C1 (fasting) and C2 (placebo with water 100 mL) cohorts. It also had better efficiency compared to the C3, C5 and C6 cohorts in that order. There were no adverse events or complications associated with endoscopy, sedation, or premedication products. Conclusions: The most effective solution as a premedication to achieve excellent visibility of the digestive mucosa was that used in the C4 cohort (SIM 200 + NAC 600 + H2OR 100 mL). The proposed TVMS scale is a very complete and easy tool to apply by more than one observer. Premedication ingested, with anti-foam, mucolytic and water up to 100 mL, between 15 and 30 minutes before endoscopy, is safe under the conditions described in this study.

Arabidopsis heterotrimeric G-protein regulates cell wall defense and resistance to necrotrophic fungi.

The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi. The agb1 mutant impaired in the Gß subunit displays enhanced susceptibility to these pathogens. Gß/AGB1 forms an obligate dimer with either one of the Arabidopsis Gγ subunits (γ1/AGG1 and γ2/AGG2). Accordingly, we now demonstrate that the agg1 agg2 double mutant is as susceptible as agb1 plants to the necrotrophic fungus Plectosphaerella cucumerina. To elucidate the molecular basis of heterotrimeric G-protein-mediated resistance, we performed a comparative transcriptomic analysis of agb1-1 mutant and wild-type plants upon inoculation with P. cucumerina. This analysis, together with metabolomic studies, demonstrated that G-protein-mediated resistance was independent of defensive pathways required for resistance to necrotrophic fungi, such as the salicylic acid, jasmonic acid, ethylene, abscisic acid, and tryptophan-derived metabolites signaling, as these pathways were not impaired in agb1 and agg1 agg2 mutants. Notably, many mis-regulated genes in agb1 plants were related with cell wall functions, which was also the case in agg1 agg2 mutant. Biochemical analyses and Fourier Transform InfraRed (FTIR) spectroscopy of cell walls from G-protein mutants revealed that the xylose content was lower in agb1 and agg1 agg2 mutants than in wild-type plants, and that mutant walls had similar FTIR spectratypes, which differed from that of wild-type plants. The data presented here suggest a canonical functionality of the Gß and Gγ1/γ2 subunits in the control of Arabidopsis immune responses and the regulation of cell wall composition.

Impairment of cellulose synthases required for Arabidopsis secondary cell wall formation enhances disease resistance.

Cellulose is synthesized by cellulose synthases (CESAs) contained in plasma membrane-localized complexes. In Arabidopsis thaliana, three types of CESA subunits (CESA4/IRREGULAR XYLEM5 [IRX5], CESA7/IRX3, and CESA8/IRX1) are required for secondary cell wall formation. We report that mutations in these proteins conferred enhanced resistance to the soil-borne bacterium Ralstonia solanacearum and the necrotrophic fungus Plectosphaerella cucumerina. By contrast, susceptibility to these pathogens was not altered in cell wall mutants of primary wall CESA subunits (CESA1, CESA3/ISOXABEN RESISTANT1 [IXR1], and CESA6/IXR2) or POWDERY MILDEW-RESISTANT5 (PMR5) and PMR6 genes. Double mutants indicated that irx-mediated resistance was independent of salicylic acid, ethylene, and jasmonate signaling. Comparative transcriptomic analyses identified a set of common irx upregulated genes, including a number of abscisic acid (ABA)-responsive, defense-related genes encoding antibiotic peptides and enzymes involved in the synthesis and activation of antimicrobial secondary metabolites. These data as well as the increased susceptibility of ABA mutants (abi1-1, abi2-1, and aba1-6) to R. solanacearum support a direct role of ABA in resistance to this pathogen. Our results also indicate that alteration of secondary cell wall integrity by inhibiting cellulose synthesis leads to specific activation of novel defense pathways that contribute to the generation of an antimicrobial-enriched environment hostile to pathogens.

Estudio prospectivo y randomizado de 2 tipos de anastomosis como método de reconstrucción después de gastrectomía total / Randomized and prospective study of 2 types of anastomosis as reconstruction method after total gastrectomy

Se realizó un estudio prospectivo y randomizado comparando los resultados inmediatos de 2 tipos de anastomosis después de gastrectomía total por cáncer gástrico. Hubo 37 pacientes seleccionados para una anastomosis esofagoyeyunal terminolateral simple y 43 pacientes para una anastomosis tipo Tomoda. No se observó diferencias significativas en ambos grupos en cuanto a características epidemiológicas. La duración de la operación, las complicaciones sépticas postoperatorias y la incidencia de fístulas anastomóticas fueron similares en ambos grupos al igual que la estadía postoperatoria. Falta evaluar los resultados a largo plazo para comprobar si hay diferencias entre ambas anastomosis