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Progressive hepatic damage and fibrosis are major features of chronic liver diseases of different etiology, yet the underlying molecular mechanisms remain to be fully defined. N-RAS, a member of the RAS family of small guanine nucleotide-binding proteins also encompassing the highly homologous H-RAS and K-RAS isoforms, was previously reported to modulate cell death and renal fibrosis; however, its role in liver damage and fibrogenesis remains unknown. Here, we approached this question by using N-RAS deficient (N-RAS-/-) mice and two experimental models of liver injury and fibrosis, namely carbon tetrachloride (CCl4) intoxication and bile duct ligation (BDL). In wild-type (N-RAS+/+) mice both hepatotoxic procedures augmented N-RAS expression in the liver. Compared to N-RAS+/+ counterparts, N-RAS-/- mice subjected to either CCl4 or BDL showed exacerbated liver injury and fibrosis, which was associated with enhanced hepatic stellate cell (HSC) activation and leukocyte infiltration in the damaged liver. At the molecular level, after CCl4 or BDL, N-RAS-/- livers exhibited augmented expression of necroptotic death markers along with JNK1/2 hyperactivation. In line with this, N-RAS ablation in a human hepatocytic cell line resulted in enhanced activation of JNK and necroptosis mediators in response to cell death stimuli. Of note, loss of hepatic N-RAS expression was characteristic of chronic liver disease patients with fibrosis. Collectively, our study unveils a novel role for N-RAS as a negative controller of the progression of liver injury and fibrogenesis, by critically downregulating signaling pathways leading to hepatocyte necroptosis. Furthermore, it suggests that N-RAS may be of potential clinical value as prognostic biomarker of progressive fibrotic liver damage, or as a novel therapeutic target for the treatment of chronic liver disease., Ministerio de Ciencia e Innovación, Unión Europea, Comunidad de Madrid, Depto. de Inmunología, Oftalmología y ORL, Fac. de Medicina, TRUE, pub

Methods We performed subtotal (90%) hepatectomies in 10 female MiniPigs using a simplified transection technique with a tourniquet. Blood tests, hepatic and systemic hemodynamics, and hepatic function and histology were assessed before (Bas), 15 min (t-15 min) and 24 h (t-24 h) after the operation. Some pigs underwent computed tomography (CT) scans for hepatic volumetry (n = 4) and intracranial pressure (ICP) monitoring (n = 3). Postoperative care was performed in an intensive care unit environment. Results All hepatectomies were successfully performed, and hepatic volumetry confirmed liver remnant volumes of 9.2% [6.2–11.2]. The hepatectomy resulted in characteristic hepatic hemodynamic alterations, including portal hyperperfusion, relative decrease of hepatic arterial blood flow, and increased portal pressure (PP) and portal-systemic pressure gradient. The model reproduced major diagnostic features including the development of cholestasis, coagulopathy, encephalopathy with increased ICP, ascites, and renal failure, hyperdynamic circulation, and hyperlactatemia. Two animals (20%) died before t-24 h. Histological liver damage was observed at t-15 min and at t-24 h. The degree of histological damage at t-24 h correlated with intraoperative PP (r = 0.689, p = 0.028), hepatic arterial blood flow (r = 0.655, p = 0.040), and hepatic arterial pulsatility index (r = 0.724, p = 0.066). All animals with intraoperative PP > 20 mmHg presented liver damage at t-24 h. Conclusion The present 90% hepatectomy porcine experimental model is a feasible and reproducible model for investigating the “Small-for-Flow” syndrome., Sociedad Española de Trasplante Hepático (SETH), Instituto de Salud Carlos III, Depto. de Farmacología y Toxicología, Fac. de Veterinaria, TRUE, pub

Curcumin is a natural molecule widely tested in preclinical and clinical studies due to its antioxidant and anti-inflammatory activity. Nevertheless, its high hydrophobicity and low bioavailability limit in vivo applications. To overcome curcumin´s drawbacks, small extracellular vesicles (sEVs) have emerged as potential drug delivery systems due to their non-immunogenicity, nanometric size and amphiphilic composition. This work presents curcumin cargo into milk sEV structure and further in vitro and in vivo evaluation as a therapeutic nanoplatform. The encapsulation of curcumin into sEV was performed by two methodologies under physiological conditions: a passive incorporation and active cargo employing saponin. Loaded sEVs (sEVCurPas and sEVCurAc) were fully characterized by physicochemical techniques, confirming that neither methodology affects the morphology or size of the nanoparticles (sEV: 113.3±5.1 nm, sEVCurPas: 127.0±4.5 nm and sEVCurAc: 98.5±3.6 nm). Through the active approach with saponin (sEVCurAc), a three-fold higher cargo was obtained (433.5 µg/mL) in comparison with the passive approach (129.1 µg/mL). These sEVCurAc were further evaluated in vitro by metabolic activity assay (MTT), confocal microscopy, and flow cytometry, showing a higher cytotoxic effect in the tumoral cells RAW264.7 and HepG2 than in primary hepatocytes, specially at high doses of sEVCurAc (4%, 15% and 30% of viability). In vivo evaluation in an experimental model of liver fibrosis confirmed sEVCurAc therapeutic effects, leading to a significant decrease of serum markers of liver damage (ALT) (557 U/L to 338 U/L with sEVCurAc therapy) and a tendency towards decreased liver fibrogenesis and extracellular matrix (ECM) deposition., Depto. de Inmunología, Oftalmología y ORL, Fac. de Medicina, TRUE, pub

Individuals exhibiting an intermediate alcohol drinking pattern in conjunction with signs of metabolic risk present clinical features of both alcohol-associated and metabolic-associated fatty liver diseases. However, such combination remains an unexplored area of great interest, given the increasing number of patients affected. In the present study, we aimed to develop a preclinical DUAL (alcohol-associated liver disease plus metabolic-associated fatty liver disease) model in mice. C57BL/6 mice received 10% vol/vol alcohol in sweetened drinking water in combination with a Western diet for 10, 23, and 52 weeks (DUAL model). Animals fed with DUAL diet elicited a significant increase in body mass index accompanied by a pronounced hypertrophy of adipocytes, hypercholesterolemia, and hyperglycemia. Significant liver damage was characterized by elevated plasma alanine aminotransferase and lactate dehydrogenase levels, extensive hepatomegaly, hepatocyte enlargement, ballooning, steatosis, hepatic cell death, and compensatory proliferation. Notably, DUAL animals developed lobular inflammation and advanced hepatic fibrosis. Sequentially, bridging cirrhotic changes were frequently observed after 12 months. Bulk RNA-sequencing analysis indicated that dysregulated molecular pathways in DUAL mice were similar to those of patients with steatohepatitis. Conclusion: Our DUAL model is characterized by obesity, glucose intolerance, liver damage, prominent steatohepatitis and fibrosis, as well as inflammation and fibrosis in white adipose tissue. Altogether, the DUAL model mimics all histological, metabolic, and transcriptomic gene signatures of human advanced steatohepatitis, and therefore serves as a preclinical tool for the development of therapeutic targets., Depto. de Inmunología, Oftalmología y ORL, Fac. de Medicina, TRUE, pub

Background. Portal vein embolization is performed weeks before extended hepatic resections to increase the future liver remnant and prevent posthepatectomy liver failure. Portal vein embolization performed closer to the operation also could be protective, but worsening of portal hyper-perfusion is a major concern. We determined the hepatic hemodynamic effects of a portal vein embolization performed 24 hours prior to hepatic operation. Methods. An extended (90%) hepatectomy was performed in swine undergoing (portal vein embolization) or not undergoing (control) a portal vein embolization 24 hours earlier (n = 10/group). Blood tests, hepatic and systemic hemodynamics, hepatic function (plasma disappearance rate of indocyanine green), liver histology, and volumetry (computed tomographic scanning) were assessed before and after the hepatectomy. Hepatocyte proliferating cell nuclear antigen expression and hepatic gene expression also were evaluated. Results. Swine in the control and portal vein embolization groups maintained stable systemic hemodynamics and developed similar increases of portal blood flow (302 ± 72% vs 486 ± 92%, P = .13). Portal pressure drastically increased in Controls (from 9.4 ± 1.3 mm Hg to 20.9 ± 1.4 mm Hg, P < .001), while being markedly attenuated in the portal vein embolization group (from 11.4 ± 1.5 mm Hg to 16.1 ± 1.3 mm Hg, P = .061). The procedure also improved the preservation of the hepatic artery blood flow, liver function, and periportal edema. These effects occurred in the absence of hepatocyte proliferation or hepatic growth and were associated with the induction of the vasoprotective gene Klf2. Conclusion. Portal vein embolization preconditioning represents a potential hepato-protective strategy for extended hepatic resections. Further preclinical studies should assess its medium-term effects, including survival. Our study also supports the relevance of hepatic hemodynamics as the main pathogenetic factor of post-hepatectomy liver fa, Mineco, ISCIII-Fondos FEDER, Sociedad Española de Trasplante Hepático, Depto. de Farmacología y Toxicología, Fac. de Veterinaria, TRUE, pub

Background: Metabolic-associated fatty liver disease (MAFLD) has risen as one of the leading etiologies for hepatocellular carcinoma (HCC). Oncogenes have been suggested to be responsible for the high risk of MAFLD-related HCC. We analyzed the impact of the proto-oncogene c-MYC in the development of human and murine MAFLD and MAFLD-associated HCC. Methods: alb-myctg mice were studied at baseline conditions and after administration of Western diet (WD) in comparison to WT littermates. c-MYC expression was analyzed in biopsies of patients with MAFLD and MAFLD-associated HCC by immunohistochemistry. Results: Mild obesity, spontaneous hyperlipidaemia, glucose intolerance and insulin resistance were characteristic of 36-week-old alb-myctg mice. Middle-aged alb-myctg exhibited liver steatosis and increased triglyceride content. Liver injury and inflammation were associated with elevated ALT, an upregulation of ER-stress response and increased ROS production, collagen deposition and compensatory proliferation. At 52 weeks, 20% of transgenic mice developed HCC. WD feeding exacerbated metabolic abnormalities, steatohepatitis, fibrogenesis and tumor prevalence. Therapeutic use of metformin partly attenuated the spontaneous MAFLD phenotype of alb-myctg mice. Importantly, upregulation and nuclear localization of c-MYC were characteristic of patients with MAFLD and MAFLD-related HCC. Conclusions: A novel function of c-MYC in MAFLD progression was identified opening new avenues for preventative strategies., Ministerio de Economía y Competitividad (MINECO), Instituto de Salud Carlos III (ISCIII), Fundación La Caixa, Asociación Española Contra el Cáncer (AECC), German Research Foundation, Fundación Ramón y Cajal, Universidad Complutense de Madrid / Banco Santander, Gobierno Andaluz / FEDER, Depto. de Genética, Fisiología y Microbiología, Fac. de Ciencias Biológicas, TRUE, pub

Las prótesis totales de rodilla (PTR) primarias tienen resultados excelentes en términos de supervivencia con cifras cercanas al 95% a 10 años, pero estos datos se empobrecen en las PTR de revisión con supervivencias cercanas al 79% a 10 años. En la cirugía de revisión suelen emplearse PTR de alta constricción como las prótesis constreñidas condilares varo-valgo (CCK) y la bisagras rotatorias (BR) siendo, teóricamente, la CCK la de menor constricción de las dos. La elección del grado de constricción suele depender del reserva ósea remanente y del estado de los ligamentos colaterales. La bibliografía disponible muestra una tendencia creciente hacia el uso de prótesis de BR frente al uso de CCK en casos complejos de cirugía de revisión..

La metatarsalgia es una causa frecuente de dolor a nivel del antepié. El tratamiento quirúrgico se basa en la realización de osteotomías a nivel de los radios menores para mejorar la distribución de las cargas y la biomecánica de marcha. En los últimos años la cirugía percutánea, y más concretamente las osteotomías metatarsales mínimamente invasivas, se han postulado como una opción quirúrgica válida con resultados similares a la cirugía abierta tradicional y menor agresión a las partes blandas. Su realización requiere la utilización de radioscopia intraoperatoria. JUSTIFICACIÓN, HIPÓTESIS Y OBJETIVOS: El objetivo de este estudio es analizar la utilidad de la ecografía en la realización de osteotomías metatarsales mínimamente invasivas...

La metatarsalgia es una causa frecuente de dolor a nivel del antepié. El tratamiento quirúrgico se basa en la realización de osteotomías a nivel de los radios menores para mejorar la distribución de las cargas y la biomecánica de marcha. En los últimos años la cirugía percutánea, y más concretamente las osteotomías metatarsales mínimamente invasivas, se han postulado como una opción quirúrgica válida con resultados similares a la cirugía abierta tradicional y menor agresión a las partes blandas. Su realización requiere la utilización de radioscopia intraoperatoria. JUSTIFICACIÓN, HIPÓTESIS Y OBJETIVOS: El objetivo de este estudio es analizar la utilidad de la ecografía en la realización de osteotomías metatarsales mínimamente invasivas..., Metatarsalgia is a frequent cause of forefoot pain. Surgical treatment is based on the performance of osteotomies at the level of the minor radii to restore a normal distribution of pressure within the forefoot and improve the biomechanics during gait. In recent years, percutaneous surgery of the foot, and specifically distal metatarsal minimal invasive osteotomy , have proven to be a valid technique, providing satisfactory clinical results, similar to open osteotomy with less soft tissue aggression. The percutaneous surgery requires intraoperative fluorocopy to be performed. BACKGROUND: This study aims to analyse our results with the surgical procedure of distal metatarsal minimally invasive osteotomy guided by ultrasonography...

Las prótesis totales de rodilla (PTR) primarias tienen resultados excelentes en términos de supervivencia con cifras cercanas al 95% a 10 años, pero estos datos se empobrecen en las PTR de revisión con supervivencias cercanas al 79% a 10 años. En la cirugía de revisión suelen emplearse PTR de alta constricción como las prótesis constreñidas condilares varo-valgo (CCK) y la bisagras rotatorias (BR) siendo, teóricamente, la CCK la de menor constricción de las dos. La elección del grado de constricción suele depender del reserva ósea remanente y del estado de los ligamentos colaterales. La bibliografía disponible muestra una tendencia creciente hacia el uso de prótesis de BR frente al uso de CCK en casos complejos de cirugía de revisión.., The number of total knee arthroplasties (TKA) implanted annually has tripled in the last decade, with a parallel increase in the number of revision surgeries. The primary TKA has excellent results in terms of survival, being close to 95% at 10 years, but these data are impoverished in the revision TKA with survivals close to 79% at 10 years.In revision surgery, highly constricted TKAs are usually used, such as constricted varus-valgus condylar prostheses (CCK) and rotating hinges (BR), with the CCK being theoretically the least constricted of them. The choice of the degree of constriction usually depends on the remaining bone stock and the collateral ligaments competence. The available literature shows a growing trend towards the use of BR prostheses compared to the use of CCK in complex cases of revision surgery...