Joaquin Martinez Tambella
Staff member publications
Trebicka, J., Gu, W., Ibañez-Samaniego, L., Hernández-Gea, V., Pitarch, C., Garcia, E., Procopet, B., Giráldez, Ã, Amitrano, L., Villanueva, C., Thabut, D., Silva-Junior, G., Martinez, J., Genescà , J., Bureau, C., Llop, E., Laleman, W., Palazon, J. M., Castellote, J., Rodrigues, S., Gluud, L., Ferreira, C. N., Barcelo, R., Cañete, N., Rodríguez, M., Ferlitsch, A., Mundi, J. L., Gronbaek, H., Hernández-Guerra, M., Sassatelli, R., Dell'Era, A., Senzolo, M., Abraldes, J. G., Romero-Gómez, M., Zipprich, A., Casas, M., Masnou, H., Primignani, M., Weiss, E., Catalina, M. V., Erasmus, H. P., Uschner, F. E., Schulz, M., Brol, M. J., Praktiknjo, M., Chang, J., Krag, A., Nevens, F., Calleja, J. L., Robic, M. A., Conejo, I., Albillos, A., Rudler, M., Alvarado, E., Guardascione, M. A., Tantau, M., Bosch, J., Torres, F., Pavesi, M., Garcia-Pagán, J. C., Jansen, C., Bañares, R., (2020). Rebleeding and mortality risk are increased by ACLF but reduced by pre-emptive TIPS Journal of Hepatology 73, (5), 1082-1091 
Background & Aims: The relationship between acute-on-chronic liver failure (ACLF) and acute variceal bleeding (AVB) is poorly understood. Specifically, the prevalence and prognosis of ACLF in the context of AVB is unclear, while the role of transjugular intrahepatic portosystemic shunt (TIPS) in the management in patients with ACLF has not been described to date.
Methods: A multicenter, international, observational study was conducted in 2,138 patients from 34 centers between 2011 and 2015. ACLF was defined and graded according to the EASL-CLIF consortium definition. Placement of pre-emptive TIPS (pTIPS) was based on individual center policy. Patients were followed-up for 1 year, until death or liver transplantation. Cox regression and competing risk models (Gray's test) were used to identify independent predictors of rebleeding or mortality.
Results: At admission, 380/2,138 (17.8%) patients had ACLF according to EASL-CLIF criteria (grade 1: 38.7%; grade 2: 39.2%; grade 3: 22.1%). The 42-day rebleeding (19% vs. 10%; p <0.001) and mortality (47% vs. 10%; p <0.001) rates were higher in patients with ACLF and increased with ACLF grades. Of note, the presence of ACLF was independently associated with rebleeding and mortality. pTIPS placement improved survival in patients with ACLF at 42 days and 1 year. This effect was also observed in propensity score matching analysis of 66 patients with ACLF, of whom 44 received pTIPs and 22 did not.
Conclusions: This large multicenter international real-life study identified ACLF at admission as an independent predictor of rebleeding and mortality in patients with AVB. Moreover, pTIPS was associated with improved survival in patients with ACLF and AVB.
Lay summary: Acute variceal bleeding is a deadly complication of liver cirrhosis that results from severe portal hypertension. This study demonstrates that the presence of acute-on-chronic liver failure (ACLF) is the strongest predictor of mortality in patients with acute variceal bleeding. Importantly, patients with ACLF and acute variceal (re)bleeding benefit from pre-emptive (early) placement of a transjugular intrahepatic portosystemic shunt.
JTD Keywords: Acute variceal bleeding, Acute-on-chronic liver failure, Cirrhosis, Rebleeding
Hernández-Gea, V., Procopet, B., Giráldez, Ã, Amitrano, L., Villanueva, C., Thabut, D., Ibañez-Samaniego, L., Silva-Junior, G., Martinez, J., Genescà, J., Bureau, C., Trebicka, J., Llop, E., Laleman, W., Palazon, J. M., Castellote, J., Rodrigues, S., Gluud, L. L., Noronha Ferreira, C., Barcelo, R., Cañete, N., Rodríguez, M., Ferlitsch, A., Mundi, J. L., Gronbaek, H., Hernández-Guerra, M., Sassatelli, R., Dell'Era, A., Senzolo, M., Abraldes, J. G., Romero-Gómez, M., Zipprich, A., Casas, M., Masnou, H., Primignani, M., Krag, A., Nevens, F., Calleja, J. L., Jansen, C., Robic, M. A., Conejo, I., Catalina, M. V., Albillos, A., Rudler, M., Alvarado, E., Guardascione, M. A., Tantau, M., Bosch, J., Torres, F., Garcia-Pagán, J. C., (2019). Preemptive-TIPS improves outcome in high-risk variceal bleeding: An observational study Hepatology 69, (1), 282-293
Patients admitted with acute variceal bleeding (AVB) and Child-Pugh C score (CP-C) or Child-Pugh B plus active bleeding at endoscopy (CP-B+AB) are at high risk for treatment failure, rebleeding, and mortality. A preemptive transjugular intrahepatic portosystemic shunt (p-TIPS) has been shown to improve survival in these patients, but its use in clinical practice has been challenged and not routinely incorporated. The present study aimed to further validate the role of preemptive TIPS in a large number of high-risk patients. This multicenter, international, observational study included 671 patients from 34 centers admitted for AVB and high risk of treatment failure. Patients were managed according to current guidelines, and use of drugs and endoscopic therapy (D+E) or p-TIPS was based on individual center policy. p-TIPS in the setting of AVB is associated with a lower mortality in CP-C patients compared with D+E (1 year mortality 22% vs. 47% in D+E group; P = 0.002). Mortality rate in CP-B+AB patients was low, and p-TIPS did not improve it. In CP-C and CP-B+AB patients, p-TIPS reduced treatment failure and rebleeding (1-year cumulative incidence function probability of remaining free of the composite endpoint: 92% vs. 74% in the D+E group; P = 0.017) and development of de novo or worsening of previous ascites without increasing rates of hepatic encephalopathy. Conclusion: p-TIPS must be the treatment of choice in CP-C patients with AVB. Because of the strong benefit in preventing further bleeding and ascites, p-TIPS could be a good treatment strategy for CP-B+AB patients..
JTD
Echalier, C., Levato, R., Mateos-Timoneda, M. A., Castaño, O., Déjean, S., Garric, X., Pinese, C., Noël, D., Engel, E., Martinez, J., Mehdi, A., Subra, G., (2017). Modular bioink for 3D printing of biocompatible hydrogels: sol-gel polymerization of hybrid peptides and polymers RSC Advances 7, (20), 12231-12235
An unprecedented generic system allowing the 3D printing of peptide-functionalized hydrogels by soft sol-gel inorganic polymerization is presented. Hybrid silylated inorganic/bioorganic blocks are mixed in biological buffer in an appropriate ratio, to yield a multicomponent bioink that can be printed as a hydrogel without using any photochemical or organic reagent. Hydrolysis and condensation of the silylated precursors occur during the printing process and result in a covalent network in which molecules are linked through siloxane bonds. The viscosity of the colloidal solution used as bioink was monitored in order to set up the optimal conditions for extrusion printing. Grid-patterned hydrogel scaffolds containing a hybrid integrin ligand were printed using a pressure-driven rapid prototyping machine. Finally, they were seeded with mesenchymal stem cells, demonstrating their suitability for cell culture. The versatility of the sol-gel process and its biocompatibility makes this approach highly promising for the preparation of tailor-made cell-laden scaffolds.
JTD
Banos, R. C., Martinez, J., Polo, C., Madrid, C., Prenafeta, A., Juarez, A., (2011). The yfeR gene of Salmonella enterica serovar Typhimurium encodes an osmoregulated LysR-type transcriptional regulator 
Fems Microbiology Letters , 315, (1), 63-71
A genetic screening for osmoregulated genes allowed us to identify the yfeR gene of Salmonella enterica serovar Typhimurium. The yfeR gene product encodes a novel LysR-type transcriptional regulator (LTTR), the expression of which decreases when external osmolarity increases. Out of the adjacent gene yfeH, YfeR modulates expression of several genes that may be required for optimal growth under low osmolarity conditions.
JTD Keywords: YfeR, Salmonella, LysR, Osmoregulation, LTTR
The 2C-methylerythritol 4-phosphate (MEP) pathway for the biosynthesis of isopentenyl pyrophosphate and its isomer dimethylallyl pyrophosphate, which are the precursors of isoprenoids, is present in plants, in the malaria parasite Plasmodium falciparum and in most eubacteria, including pathogenic agents. However, the MEP pathway is absent from fungi and animals, which have exclusively the mevalonic acid pathway. Given the characteristics of the MEP pathway, its enzymes represent potential targets for the generation of selective antibacterial, antimalarial and herbicidal molecules. We have focussed on the enzyme 4-(cytidine 5'-diphospho)-2-C-methyl-D: -erythritol kinase (CMK), which catalyses the fourth reaction step of the MEP pathway. A molecular dynamics simulation was carried out on the CMK dimer complex, and protein-protein interactions analysed, considering also water-mediated interactions between monomers. In order to find small molecules that bind to CMK and disrupt dimer formation, interactions observed in the dynamics trajectory were used to model a pharmacophore used in database searches. Using an intensity-fading matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry approach, one compound was found to interact with CMK. The data presented here indicate that a virtual screening approach can be used to identify candidate molecules that disrupt the CMK-CMK complex. This strategy can contribute to speeding up the discovery of new antimalarial, antibacterial, and herbicidal compounds.
JTD Keywords: Solvent-mediated interactions, Protein-protein interactions, Molecular dynamics, Drug design, Intensisty-fading MALDI-TOF mass spectrometry
