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Valorization of the hemicellulose fraction of plant biomass is crucial for the sustainability of lignocellulosic biorefineries. The Cellulomonas genus comprises Gram-positive Actinobacteria that degrade cellulose and other polysaccharides by secreting a complex array of enzymes. In this work, we studied the specificity and synergy of two enzymes, CsXyn10A and CsAbf62A, which were identified as highly abundant in the extracellular proteome of Cellulomonas sp. B6 when grown on wheat bran. To explore their potential for bioprocessing, the recombinant enzymes were expressed and their activities were thoroughly characterized. rCsXyn10A is a GH10 endo-xylanase (EC 3.2.1.8), active across a broad pH range (5 to 9), at temperatures up to 55 °C. rCsAbf62A is an α-L-arabinofuranosidase (ABF) (EC 3.2.1.55) that specifically removes α-1,2 and α-1,3-L-arabinosyl substituents from arabino-xylo-oligosaccharides (AXOS), xylan, and arabinan backbones, but it cannot act on double-substituted residues. It also has activity on pNPA. No differences were observed regarding activity when CsAbf62A was expressed with its appended CBM13 module or only the catalytic domain. The amount of xylobiose released from either wheat arabinoxylan or arabino-xylo-oligosaccharides increased significantly when rCsXyn10A was supplemented with rCsAbf62A, indicating that the removal of arabinosyl residues by rCsAbf62A improved rCsXyn10A accessibility to ß-1,4-xylose linkages, but no synergism was observed in the deconstruction of wheat bran. These results contribute to designing tailor-made, substrate-specific, enzymatic cocktails for xylan valorization. KEY POINTS: • rCsAbf62A removes α-1,2 and α-1,3-L-arabinosyl substituents from arabino-xylo-oligosaccharides, xylan, and arabinan backbones. • The appended CBM13 of rCsAbf62A did not affect the specific activity of the enzyme. • Supplementation of rCsXyn10A with rCsAbf62A improves the degradation of AXOS and xylan.

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RESUMEN Introducción: El feocromocitoma es una neoplasia neuroendocrina localizada en la médula adrenal. Objetivo: Destacar la importancia que todavía posee en la práctica clínica el interrogatorio y el examen físico minucioso, a pesar de los novedosos medios diagnósticos con que se cuenta en la actualidad. Presentación del caso : Se presenta caso clínico de paciente masculino de 17 años de edad, con incidentaloma suprarrenal izquierdo, catalogado inicialmente como tumor renal abscedado, cuya biopsia de pieza operatoria demostró finalmente que correspondía a un feocromocitoma benigno. La determinación de catecolaminas fue normal, en la tomografía computarizada se evidenció una masa retroperitoneal que involucraba riñón y suprarrenal izquierdos. Se realizó la resección de la neoplasia y fue dado de alta médica en buenas condiciones. Conclusiones: El feocromocitoma es una patología infrecuente y compleja, cuya resolución quirúrgica es mandatoria.

ABSTRACT Background: Pheochromocytoma is a neuroendocrine neoplasm located in the adrenal medulla. Objective: To highlight the importance of physical examination and the detailed clinical practice, despite the new diagnostic means that are currently available. Case presentation: A 17-years-old male patient with left adrenal incidentaloma, initially classified as an abscessed renal tumor, whose surgical specimen biopsy finally showed that it corresponded to a benign pheochromocytoma it is presented. The catecholamine determination was normal, the computed tomography revealed a retroperitoneal mass that involved the left kidney and adrenal. The neoplasm was resected and he was discharged in good condition. Conclusions: Pheochromocytoma is an infrequent and complex pathology, whose surgical resolution is necessary.

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One of the main distinguishing features of bacteria belonging to the Cellulomonas genus is their ability to secrete multiple polysaccharide degrading enzymes. However, their application in biomass deconstruction still constitutes a challenge. We addressed the optimisation of the xylanolytic activities in extracellular enzymatic extracts of Cellulomonas sp. B6 and Cellulomonas fimi B-402 for their subsequent application in lignocellulosic biomass hydrolysis by culture in several substrates. As demonstrated by secretomic profiling, wheat bran and waste paper resulted to be suitable inducers for the secretion of xylanases of Cellulomonas sp. B6 and C. fimi B-402, respectively. Both strains showed high xylanolytic activity in culture supernatant although Cellulomonas sp. B6 was the most efficient xylanolytic strain. Upscaling from flasks to fermentation in a bench scale bioreactor resulted in equivalent production of extracellular xylanolytic enzymatic extracts and freeze drying was a successful method for concentration and conservation of the extracellular enzymes, retaining 80% activity. Moreover, enzymatic cocktails composed of combined extra and intracellular extracts effectively hydrolysed the hemicellulose fraction of extruded barley straw into xylose and xylooligosaccharides. KEY POINTS: • Secreted xylanase activity of Cellulomonas sp. B6 and C. fimi was maximised. • Biomass-induced extracellular enzymes were identified by proteomic profiling. • Combinations of extra and intracellular extracts were used for barley straw hydrolysis.

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Introducción: La litiasis vesical secundaria se forma en el reservorio vesical y requiere la existencia de condiciones patológicas previas como lo son los cuerpos extraños. Objetivo: Describir dos casos clínicos de litiasis vesical secundaria a migración de un dispositivo intrauterino. Caso clínico: Se presentan dos casos de migración intravesical de dispositivo intrauterino con litiasis vesical secundaria. Se diagnosticaron años después de su inserción, ante la aparición de dolor pélvico, cistitis a repetición y hematuria. La laparoscopia no fue útil para su diagnóstico. En consulta de Urología la ultrasonografía y la radiografía de pelvis fueron herramientas diagnósticas útiles ante la sospecha inicial de esta patología. Presentaron buena evolución y regresión total de los síntomas tras cistolitotomía suprapúbica. Conclusión: Se debe pensar en la posibilidad de migración de un dispositivo intrauterino a vejiga ante la cronicidad de síntomas urinarios irritativos bajos en toda mujer que emplee este método anticonceptivo y desconozca su paradero(AU)

Introduction: Secondary bladder lithiasis is formed in the bladder reservoir and requires the existence of previous pathological conditions such as foreign bodies. Objective: To describe two clinical cases of bladder lithiasis secondary to intrauterine device migration. Clinical case report: Two cases of intravesical migration of an intrauterine device with secondary bladder stones are reported. They were diagnosed years after insertion, due to the appearance of pelvic pain, recurrent cystitis and hematuria. Laparoscopy was not helpful for its diagnosis. In Urology consultation, ultrasound and pelvic radiography were useful diagnostic tools in the event of the initial suspicion of this pathology. They showed good evolution and total regression of symptoms after suprapubic cystolithotomy. Conclusion: The possibility of an intrauterine device migration to the bladder should be considered when chronicity of irritative low urinary symptoms in every woman who uses this contraceptive method and which locations are unknown(AU)

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In the efficient bioconversion of polysaccharides from lignocellulosic biomass, endoglucanases and ß-glucosidases are key enzymes for the deconstruction of ß-glucans. In this work, we focused on a GH8 endoglucanase (Cel8Pa) and a GH1 ß-glucosidase (Bg1Pa) from Paenibacillus xylanivorans A59. Cel8Pa was active on a broad range of substrates, such as ß-glucan from barley (24.5 IU/mg), lichenan (17.9 IU/mg), phosphoric acid swollen cellulose (PASC) (9.7 IU/mg), carboxi-methylcellulose (CMC) (7.3 IU/mg), chitosan (1.4 IU/mg) and xylan (0.4 IU/mg). Bg1Pa was active on cellobiose (C2) and cello-oligosaccharides up to C6, releasing glucose as the main product. When both enzymes were used jointly, there was a synergic effect in the conversion rate of polysaccharides to glucose. Cel8Pa and Bg1Pa presented important properties for simultaneous saccharification and fermentation (SSF) processes in second generation bioethanol production, such as tolerance to high concentration of glucose and ethanol.

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Woody biomass represents an important source of carbon on earth, and its global recycling is highly dependent on Agaricomycetes fungi. White-rot Basidiomycetes are a very important group in this regard, as they possess a large and diverse enzymatic repertoire for biomass decomposition. Among these enzymes, the recently discovered lytic polysaccharide monooxygenases (LPMOs) have revolutionized biomass processing with their novel oxidative mechanism of action. The strikingly high representation of LPMOs in fungal genomes raises the question of their functional versatility. In this work, we studied an AA9 LPMO from the white-rot basidiomycete Pycnoporus sanguineus, PsAA9A. Successfully produced as a recombinant secreted protein in Pichia pastoris, PsAA9A was found to be a C1-specific LPMO active on cellulosic substrates, generating native and oxidized cello-oligosaccharides in the presence of an external electron donor. PsAA9A boosted cellulolytic activity of glysoside hydrolases from families GH1, GH5, and GH6.This study serves as a starting point towards understanding the functional versatility and biotechnological potential of this enzymatic family, highly represented in wood decay fungi, in Pycnoporus genus. KEY POINTS: • PsAA9A is the first AA9 from P. sanguineus to be characterized. • PsAA9A has activity on cellulose, producing C1-oxidized cello-oligosaccharides. • Boosting activity with GH1, GH5, and GH6 was proven.

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Glycoside hydrolase family 8 (GH8) includes endoglucanases, lichenases, chitosanases and xylanases, which are essential for polysaccharides breakdown. In this work, we studied a thermally stable GH8 from the cellulose synthase complex of Enterobacter sp. R1, for deconstruction of ß-glucans. The biochemical characterization of the recombinant GH8ErCel showed high specificity towards barley ß-glucan and lichenan and lower activity on carboxymethylcellulose and swollen cellulose, yielding different length oligosaccharides. By molecular modeling, six conserved subsites for glucose binding and some possible determinants for its lack of xylanase and chitosanase activity were identified. GH8ErCel was active at a broad range of pH and temperature and presented remarkable stability at 60 °C. Additionally, it hydrolyzed ß-glucan from oat and wheat brans mainly to tri- and tetraoligosaccharides. Therefore, GH8ErCel may be a good candidate for enzymatic deconstruction of ß-glucans at high temperature in food and feed industries, including the production of prebiotics and functional foods.

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