First consensus document of waiting list prioritization for liver transplantation by the Spanish Society of Liver Transplantation (SETH).

Spain is worldwide leader in deceased donation rates per million habitants and count on a strong network of twenty-five liver transplant institutions. Although the access to liver transplantation is higher than in other countries, approximately 10% of patients qualifying for liver transplantation in Spain will die in the waiting list or would be excluded due to clinical deterioration. A robust waiting list prioritization system is paramount to grant the sickest patients with the first positions in the waiting list for an earlier access to transplant. In addition, the allocation policy may not create or perpetuate inequities, particularly in a public and universal healthcare system. Hitherto, Spain lacks a unique national allocation system for elective liver transplantation. Most institutions establish their own rules for liver allocation and only two autonomous regions, namely Andalucía and Cataluña, share part of their waiting list within their territory to provide regional priority to patients requiring more urgent transplantation. This heterogeneity is further aggravated by the recently described sex-based disparities for accessing liver transplantation in Spain, and by the expansion of liver transplant indications, mainly for oncological indications, in absence of clear guidance on the optimal prioritization policy. The present document contains the recommendations from the first consensus of waiting list prioritization for liver transplantation issued by the Spanish Society of Liver Transplantation (SETH). The document was supported by all liver transplant institutions in Spain and by the Organización Nacional de Trasplantes (ONT). Its implementation will allow to homogenize practices and to improve equity and outcomes among patients with end-stage liver disease.

FibroScan compared to liver biopsy for accurately staging recurrent hepatic steatosis and fibrosis after transplantation for MASH.

BACKGROUND AND AIMS: Metabolic dysfunction-associated steatotic liver disease (MASLD) recurrence after liver transplantation (LT) seems unavoidable and gradual. We aimed to evaluate the diagnostic accuracy in the post-LT setting of patients transplanted for metabolic dysfunction-associated steatohepatitis (MASH) of recurrent hepatic steatosis and fibrosis identified with FibroScan, compared to biopsy findings. METHODS: This prospective cohort study included adults transplanted for MASH between 2010 and 2022 in three LT centres in Spain who underwent FibroScan and biopsy at least 1-year after LT. RESULTS: In total, 44 patients transplanted for MASH after LT were included. The median time from LT to biopsy and FibroScan was 24.5 (interquartile range [IQR]:16-46) and 26.0 (IQR: 16.8-41.5) months, respectively. The median time between biopsy and FibroScan was 2.0 (IQR: 0-5) months. On FibroScan, significant steatosis was diagnosed in about half of the patients (n = 21, 47.7%), yet advanced fibrosis in only two cases (4.6%). On biopsy, a quarter of biopsied patients (n = 11, 25%) had a MASH diagnosis, two (4.6%) with significant fibrosis and one (2.3%) with cirrhosis. All patients with liver stiffness measurement (LSM) values <8 kPa (n = 35, 79.5%) had a fibrosis stage ≤F1 (negative predictive value = 100%). The combination of post-LT hypertension (odds ratio [OR]: 12.0, 95% confidence interval [CI]: 1.8-80.4, p = .010) and post-LT dyslipidaemia (OR: 7.9, 95% CI: 1.3-47.1, p = .024) with LSM (OR: 1.7, 95% CI: 1.1-2.8, p = .030) was independently associated with MASLD. CONCLUSIONS: Although biopsy remains the gold standard for detecting fibrosis, our results suggest that LSM values <8 kPa after LT for MASH are strongly correlated with absence of significant/advanced fibrosis.

Reproductive and pregnancy control in Wilson disease patients in Spain.

BACKGROUND AND AIM: Recommendations on pregnancy, lactation, and contraception in women with Wilson disease are briefly stated in international guidelines but are not entirely homogeneous. Data regarding the management of these special events among patients with Wilson disease in Spain are lacking. We used the Wilson Registry platform of the Spanish Association for the Study of the Liver to question patients on their reproductive and gestational lives. METHODS: This was a multicentre ambispective study including adult women with Wilson disease in the Spanish Wilson Registry interviewed about their contraception, childbearing, pregnancy, and lactation experiences. Clinical and analytical data were extracted from the registry. RESULTS: The study included 92 women from 17 centres in Spain. Most (63%) reported having a previous pregnancy history. The rate of spontaneous miscarriages was 21.6%, mainly occurring in the first trimester and up to one third among undiagnosed patients. Most pregnant women received chelator therapy during pregnancy, but dose reduction was recommended in less than 10%. After delivery, artificial lactation predominated (60.3%) and its use was mainly based on physician's recommendations (68%). Up to 40% of the women included reported some concerns about their reproductive lives, mainly related to the potential drug toxicity to their children. Most of the patients considered the information given by specialists to be sufficient. CONCLUSION: Gestational management among women with Wilson disease in Spain was found to be highly heterogeneous and frequently different from what is described in international guidelines. Education on rare liver diseases should be a priority for scientific societies in order to homogenize patient follow-up and recommendations.

GEMA-Na and MELD 3.0 severity scores to address sex disparities for accessing liver transplantation: a nationwide retrospective cohort study.

Background: The Gender-Equity Model for liver Allocation corrected by serum sodium (GEMA-Na) and the Model for End-stage Liver Disease 3.0 (MELD 3.0) could amend sex disparities for accessing liver transplantation (LT). We aimed to assess these inequities in Spain and to compare the performance of GEMA-Na and MELD 3.0. Methods: Nationwide cohort study including adult patients listed for a first elective LT (January 2016-December 2021). The primary outcome was mortality or delisting for sickness within the first 90 days. Independent predictors of the primary outcome were evaluated using multivariate Cox's regression with adjusted relative risks (RR) and 95% confidence intervals (95% CI). The discrimination of GEMA-Na and MELD 3.0was assessed using Harrell c-statistics (Hc). Findings: The study included 6071 patients (4697 men and 1374 women). Mortality or delisting for clinical deterioration occurred in 286 patients at 90 days (4.7%). Women had reduced access to LT (83.7% vs. 85.9%; p = 0.037) and increased risk of mortality or delisting for sickness at 90 days (adjusted RR = 1.57 [95% CI 1.09-2.28]; p = 0.017). Female sex remained as an independent risk factor when using MELD or MELD-Na but lost its significance in the presence of GEMA-Na or MELD 3.0. Among patients included for reasons other than tumours (n = 3606; 59.4%), GEMA-Na had Hc = 0.753 (95% CI 0.715-0.792), which was higher than MELD 3.0 (Hc = 0.726 [95% CI 0.686-0.767; p = 0.001), showing both models adequate calibration. Interpretation: GEMA-Na and MELD 3.0 might correct sex disparities for accessing LT, but GEMA-Na provides more accurate predictions of waiting list outcomes and could be considered the standard of care for waiting list prioritization. Funding: Instituto de Salud Carlos III, Agencia Estatal de Investigación (Spain), and European Union.

Characterizing Hepatitis Delta in Spain and the gaps in its management.

BACKGROUND AND AIMS: Chronic hepatitis D (CHD) is a severe form of chronic viral hepatitis. The estimated hepatitis delta prevalence in Spain is around 5% of patients with hepatitis B. Reimbursement of new antiviral therapies (Bulevirtide, BLV) was delayed in our country until February 2024. We aimed to characterize the clinical profile of patients with HDV/HBV infection in Spain and current barriers in their management at the time of BLV approval. METHOD: Multicenter registry including patients with positive anti-HDV serology actively monitored in 30 Spanish centers. Epidemiological, clinical and virological variables were recorded at the start of follow-up and at the last visit. RESULTS: We identified 329 anti-HDV patients, 41% were female with median age 51 years. The most common geographical origin was Spain (53%) and East Europe (24%). Patients from Spain were older and had HCV and HIV coinfection probably associated to past drug injection (p<0.01). HDV-RNA was positive in 138 of 221 assessed (62%). Liver cirrhosis was present at diagnosis in 33% and it was more frequent among viremic patients (58% vs 25%, p<0.01). After a median follow-up of 6 (3-12) years, 44 (16%) resolved infection (18 spontaneously and 26 after Peg-INF). An additional 10% of patients developed cirrhosis (n=137) during follow-up (45% had portal hypertension and 14% liver decompensation). Liver disease progression was associated to persisting viremia. CONCLUSION: One-third of the patients with CHD already have cirrhosis at diagnosis. Persistence of positive viremia is associated to rapid liver disease progression. Importantly, barriers to locally determine/quantify HDV-RNA were present.

Multidrug-resistant bacterial infections after liver transplantation: Prevalence, impact, and risk factors.

BACKGROUND & AIMS: Infections by multidrug-resistant bacteria (MDRB) are an increasing healthcare problem worldwide. This study analyzes the incidence, burden, and risk factors associated with MDRB infections after liver transplant(ation) (LT). METHODS: This retrospective, multicenter cohort study included adult patients who underwent LT between January 2017 and January 2020. Risk factors related to pre-LT disease, surgical procedure, and postoperative stay were analyzed. Multivariate logistic regression analysis was performed to identify independent predictors of MDRB infections within the first 90 days after LT. RESULTS: We included 1,045 LT procedures (960 patients) performed at nine centers across Spain. The mean age of our cohort was 56.8 ± 9.3 years; 75.4% (n = 782) were male. Alcohol-related liver disease was the most prevalent underlying etiology (43.2.%, n = 451). Bacterial infections occurred in 432 patients (41.3%) who presented with a total of 679 episodes of infection (respiratory infections, 19.3%; urinary tract infections, 18.5%; bacteremia, 13.2% and cholangitis 11%, among others). MDRB were isolated in 227 LT cases (21.7%) (348 episodes). Enterococcus faecium (22.1%), Escherichia coli (18.4%), and Pseudomonas aeruginosa (15.2%) were the most frequently isolated microorganisms. In multivariate analysis, previous intensive care unit admission (0-3 months before LT), previous MDRB infections (0-3 months before LT), and an increasing number of packed red blood cell units transfused during surgery were identified as independent predictors of MDRB infections. Mortality at 30, 90, 180, and 365 days was significantly higher in patients with MDRB isolates. CONCLUSION: MDRB infections are highly prevalent after LT and have a significant impact on prognosis. Enterococcus faecium is the most frequently isolated multi-resistant microorganism. New pharmacological and surveillance strategies aimed at preventing MDRB infections after LT should be considered for patients with risk factors. IMPACT AND IMPLICATIONS: Multidrug-resistant bacterial infections have a deep impact on morbidity and mortality after liver transplantation. Strategies aimed at improving prophylaxis, early identification, and empirical treatment are paramount. Our study unveiled the prevalence and main risk factors associated with these infections, and demonstrated that gram-positive bacteria, particularly Enterococcus faecium, are frequent in this clinical scenario. These findings provide valuable insights for the development of prophylactic and empirical antibiotic treatment protocols after liver transplantation.

Higher Plant-Derived Biostimulants: Mechanisms of Action and Their Role in Mitigating Plant Abiotic Stress.

Modern agriculture is being challenged by deteriorating edaphoclimatic conditions and increasing anthropogenic pressure. This necessitates the development of innovative crop production systems that can sustainably meet the demands of a growing world population while minimizing the environmental impact. The use of plant biostimulants is gaining ground as a safe and ecologically sound approach to improving crop yields. In this review, biostimulants obtained from different higher plant sources are presented under the term higher plant-derived biostimulants (hPDBs). Their mechanisms of action regulate physiological processes in plants from germination to fructification, conditioned by responses induced in plant mineral nutrition and primary metabolism, specialized metabolism, photosynthetic processes, oxidative metabolism, and signaling-related processes. The aim of this review is to collect and unify the abundant information dispersed in the literature on the effects of these biostimulants, focusing on crops subjected to abiotic stress conditions and the underlying mechanisms of action.

Clinical profile of Spanish hepatitisC virus-infected treatment-naïve patients with compensated cirrhosis in the CREST study. / Perfil clínico de los pacientes españoles con hepatitisC naïve con cirrosis compensada tratados en el estudio CREST.

BACKGROUND AND AIM OF THE STUDY: There are still patients with hepatitisC in Spain who have yet to be diagnosed, but their clinical profile is unclear. In 2021, 21.93% of patients diagnosed had cirrhosis and were mostly treatment-naïve. METHODS: This sub-analysis describes the clinical profile of the 60Spanish treatment-naïve patients with compensated cirrhosis who were included in the CREST study. MAJOR RESULTS: Sixty percent of patients were male, median age 56years, and 33% had a history of drug use. Almost three-quarters (71.3%) had more than one comorbidity and 78.3% took concomitant medication. At treatment initiation, median platelet count was 139×103/µL and FibroScan® 17kPa. No virological failure was observed and no patient discontinued treatment due to adverse events. No clinically significant changes were noted during or after treatment in the median platelet, albumin, bilirubin, and transaminase levels. CONCLUSIONS: Treatment with glecaprevir/pibrentasvir for 8weeks in this cohort of treatment-naïve patients with compensated cirrhosis in Spain was safe and effective. This information reinforces the use of this short antiviral regimen even when there is compensated cirrhosis, simplifying the approach to hepatitisC among those patients still to be diagnosed and treated in Spain.

Recruitment of the 40S ribosomal subunit by the West Nile virus 3' UTR promotes the cross-talk between the viral genomic ends for translation regulation.

Flaviviral RNA genomes are composed of discrete RNA structural units arranged in an ordered fashion and grouped into complex folded domains that regulate essential viral functions, e.g. replication and translation. This is achieved by adjusting the overall structure of the RNA genome via the establishment of inter- and intramolecular interactions. Translation regulation is likely the main process controlling flaviviral gene expression. Although the genomic 3' UTR is a key player in this regulation, little is known about the molecular mechanisms underlying this role. The present work provides evidence for the specific recruitment of the 40S ribosomal subunit by the 3' UTR of the West Nile virus RNA genome, showing that the joint action of both genomic ends contributes the positioning of the 40S subunit at the 5' end. The combination of structural mapping techniques revealed specific conformational requirements at the 3' UTR for 40S binding, involving the highly conserved SL-III, 5'DB, 3'DB and 3'SL elements, all involved in the translation regulation. These results point to the 40S subunit as a bridge to ensure cross-talk between both genomic ends during viral translation and support a link between 40S recruitment by the 3' UTR and translation control.

Screening and risk of hepatocellular carcinoma in patients with advanced fibrosis after hepatitis C virus eradication.

INTRODUCTION: the risk of hepatocellular carcinoma (HCC) after eradication of the hepatitis C virus (HCV) is highly variable in patients with advanced fibrosis (F3). Long-term surveillance for HCC after sustained virological response (SVR) is controversial in these patients. The objective of this study was to describe the post-SVR follow-up in clinical practice in patients with F3 and determine the predictive factors for the development of HCC. PATIENTS AND METHODS: a multicenter, observational and retrospective study was performed, which included HCV-monoinfected patients with F3 fibrosis determined by transient elastography who achieved SVR between 2015 and 2022, with follow-up until May 2023. Clinical-demographic, laboratory, elastography, and ultrasound variables were recorded before and after treatment. A descriptive and inferential analysis, Cox regression analysis and survival analysis were carried out with the R statistical software. RESULTS: two hundred and nineteen patients were included in the study (65.3 % males, median age 57 years), and 175 (79.9 %) received ultrasound screening after SVR for 62 (6-90) months. The prescribing service was the only independent variable related to performing ultrasound surveillance (p = 0.004). Eight patients developed HCC. In multivariate analysis adjusted for sex, age, presence of diabetes and alcohol consumption, a post-SVR FIB-4 ≥ 3.25 was associated with a 12-fold increase in HCC risk. The cumulative probability of HCC was higher in the group of patients with FIB-4 ≥ 3.25 after SVR (p < 0.001). CONCLUSION: post-SVR follow-up of patients with F3 fibrosis is variable in clinical practice. Using the FIB-4 after SVR allows us to identify those patients with a higher risk of HCC who benefit from biannual ultrasound screening.

Inter- and Intramolecular RNA-RNA Interactions Modulate the Regulation of Translation Mediated by the 3' UTR in West Nile Virus.

RNA viruses rely on genomic structural elements to accomplish the functions necessary to complete the viral cycle. These elements participate in a dynamic network of RNA-RNA interactions that determine the overall folding of the RNA genome and may be responsible for the fine regulation of viral replication and translation as well as the transition between them. The genomes of members of the genus Flavivirus are characterized by a complexly folded 3' UTR with a number of RNA structural elements that are conserved across isolates of each species. The present work provides evidence of intra- and intermolecular RNA-RNA interactions involving RNA structural elements in the 3' UTR of the West Nile virus genome. The intermolecular interactions can be visualized in vitro by the formation of molecular dimers involving the participation of at least the SLI and 3'DB elements. Certainly, the 3' UTR of dengue virus, which lacks the SLI element, forms molecular dimers in lower quantities via a single interaction site, probably 3'DB. The functional analysis of sequence or deletion mutants revealed an inverse relationship between 3' UTR dimerization and viral translation efficiency in cell cultures. A network of RNA-RNA interactions involving 3' UTR structural elements might therefore exist, helping to regulate viral translation.

Significant heterogeneity in the diagnosis and long-term management of Wilson disease: Results from a large multicenter Spanish study.

There is uncertainty regarding Wilson's disease (WD) management. OBJECTIVES: To assess, in a multicenter Spanish retrospective cohort study, whether the approach to WD is homogeneous among centers. METHODS: Data on WD patients followed at 32 Spanish hospitals were collected. RESULTS: 153 cases, 58% men, 20.6 years at diagnosis, 69.1% hepatic presentation, were followed for 15.5 years. Discordant results in non-invasive laboratory parameters were present in 39.8%. Intrahepatic copper concentration was pathologic in 82.4%. Genetic testing was only done in 56.6% with positive results in 83.9%. A definite WD diagnosis (Leipzig score ≥4) was retrospectively confirmed in 92.5% of cases. Chelating agents were standard initial therapy (75.2%) with frequent modifications (57%), particularly to maintenance zinc. Enzyme normalization was not achieved by one third, most commonly in the setting of poor compliance, lack of genetic mutations and/or presence of cardiometabolic risk factors. Although not statistically significant, there were trends for sex differences in number of diagnosed cases, age at diagnosis and biochemical response. CONCLUSIONS: Significant heterogeneity in diagnosis and management of WD patients emerges from this multicenter study that includes both small and large reference centers. The incorporation of genetic testing will likely improve diagnosis. Sex differences need to be further explored.

Nivolumab after selective internal radiation therapy for the treatment of hepatocellular carcinoma: a phase 2, single-arm study.

PURPOSE: To evaluate the safety and efficacy of selective internal radiation therapy (SIRT) in combination with a PD-1 inhibitor in patients with unresectable hepatocellular carcinoma (uHCC) and liver-only disease ineligible for chemoembolization. PATIENTS AND METHODS: NASIR-HCC is a single-arm, multicenter, open-label, phase 2 trial that recruited from 2017 to 2019 patients who were naïve to immunotherapy and had tumors in the BCLC B2 substage (single or multiple tumors beyond the up-to-7 rule), or unilobar tumors with segmental or lobar portal vein invasion (PVI); no extrahepatic spread; and preserved liver function. Patients received SIRT followed 3 weeks later by nivolumab (240 mg every 2 weeks) for up to 24 doses or until disease progression or unacceptable toxicity. Safety was the primary endpoint. Secondary objectives included objective response rate (ORR), time to progression (TTP), and overall survival (OS). RESULTS: 42 patients received SIRT (31 BCLC-B2, 11 with PVI) and were followed for a median of 22.2 months. 27 patients discontinued and 1 never received Nivolumab. 41 patients had any-grade adverse events (AE) and 21 had serious AEs (SAE). Treatment-related AEs and SAEs grade 3-4 occurred in 8 and 5 patients, respectively. Using RECIST 1.1 criteria, ORR reported by investigators was 41.5% (95% CI 26.3% to 57.9%). Four patients were downstaged to partial hepatectomy. Median TTP was 8.8 months (95% CI 7.0 to 10.5) and median OS was 20.9 months (95% CI 17.7 to 24.1). CONCLUSIONS: The combination of SIRT and nivolumab has shown an acceptable safety profile and signs of antitumor activity in the treatment of patients with uHCC that were fit for SIRT. TRIAL REGISTRATION NUMBER: NCT03380130.

Redox post-translational modifications and their interplay in plant abiotic stress tolerance.

The impact of climate change entails a progressive and inexorable modification of the Earth's climate and events such as salinity, drought, extreme temperatures, high luminous intensity and ultraviolet radiation tend to be more numerous and prolonged in time. Plants face their exposure to these abiotic stresses or their combination through multiple physiological, metabolic and molecular mechanisms, to achieve the long-awaited acclimatization to these extreme conditions, and to thereby increase their survival rate. In recent decades, the increase in the intensity and duration of these climatological events have intensified research into the mechanisms behind plant tolerance to them, with great advances in this field. Among these mechanisms, the overproduction of molecular reactive species stands out, mainly reactive oxygen, nitrogen and sulfur species. These molecules have a dual activity, as they participate in signaling processes under physiological conditions, but, under stress conditions, their production increases, interacting with each other and modifying and-or damaging the main cellular components: lipids, carbohydrates, nucleic acids and proteins. The latter have amino acids in their sequence that are susceptible to post-translational modifications, both reversible and irreversible, through the different reactive species generated by abiotic stresses (redox-based PTMs). Some research suggests that this process does not occur randomly, but that the modification of critical residues in enzymes modulates their biological activity, being able to enhance or inhibit complete metabolic pathways in the process of acclimatization and tolerance to the exposure to the different abiotic stresses. Given the importance of these PTMs-based regulation mechanisms in the acclimatization processes of plants, the present review gathers the knowledge generated in recent years on this subject, delving into the PTMs of the redox-regulated enzymes of plant metabolism, and those that participate in the main stress-related pathways, such as oxidative metabolism, primary metabolism, cell signaling events, and photosynthetic metabolism. The aim is to unify the existing information thus far obtained to shed light on possible fields of future research in the search for the resilience of plants to climate change.

The Genomic 3' UTR of Flaviviruses Is a Translation Initiation Enhancer.

Viruses rely on the cellular machinery of host cells to synthesize their proteins, and have developed different mechanisms enabling them to compete with cellular mRNAs for access to it. The genus Flavivirus is a large group of positive, single-stranded RNA viruses that includes several important human pathogens, such as West Nile, Dengue and Zika virus. The genome of flaviviruses bears a type 1 cap structure at its 5' end, needed for the main translation initiation mechanism. Several members of the genus also use a cap-independent translation mechanism. The present work provides evidence that the WNV 5' end also promotes a cap-independent translation initiation mechanism in mammalian and insect cells, reinforcing the hypothesis that this might be a general strategy of flaviviruses. In agreement with previous reports, we show that this mechanism depends on the presence of the viral genomic 3' UTR. The results also show that the 3' UTR of the WNV genome enhances translation of the cap-dependent mechanism. Interestingly, WNV 3' UTR can be replaced by the 3' UTR of other flaviviruses and the translation enhancing effect is maintained, suggesting a molecular mechanism that does not involve direct RNA-RNA interactions to be at work. In addition, the deletion of specific structural elements of the WNV 3' UTR leads to increased cap-dependent and cap-independent translation. These findings suggest the 3' UTR to be involved in a fine-tuned translation regulation mechanism.

Interaction between Melatonin and NO: Action Mechanisms, Main Targets, and Putative Roles of the Emerging Molecule NOmela.

Melatonin (MEL), a ubiquitous indolamine molecule, has gained interest in the last few decades due to its regulatory role in plant metabolism. Likewise, nitric oxide (NO), a gasotransmitter, can also affect plant molecular pathways due to its function as a signaling molecule. Both MEL and NO can interact at multiple levels under abiotic stress, starting with their own biosynthetic pathways and inducing a particular signaling response in plants. Moreover, their interaction can result in the formation of NOmela, a very recently discovered nitrosated form of MEL with promising roles in plant physiology. This review summarizes the role of NO and MEL molecules during plant development and fruit ripening, as well as their interactions. Due to the impact of climate-change-related abiotic stresses on agriculture, this review also focuses on the role of these molecules in mediating abiotic stress tolerance and the main mechanisms by which they operate, from the upregulation of the entire antioxidant defense system to the post-translational modifications (PTMs) of important molecules. Their individual interaction and crosstalk with phytohormones and H2S are also discussed. Finally, we introduce and summarize the little information available about NOmela, an emerging and still very unknown molecule, but that seems to have a stronger potential than MEL and NO separately in mediating plant stress response.

How Donor and Surgical Factors Affect the Viability and Functionality of Human Hepatocytes Isolated From Liver Resections.

Liver resections are a significant source of primary human hepatocytes used mainly in artificial liver devices and pharmacological and biomedical studies. However, it is not well known how patient-donor and surgery-dependent factors influence isolated hepatocytes' yield, viability, and function. Hence, we aimed to analyze the impact of all these elements on the outcome of human hepatocyte isolation. Patients and methods: Hepatocytes were isolated from liver tissue from patients undergoing partial hepatectomy using a two-step collagenase method. Hepatocyte viability, cell yield, adhesion, and functionality were measured. In addition, clinical and analytical patient variables were collected and the use or absence of vascular clamping and its type (continuous or intermittent) plus the ischemia times during surgery. Results: Malignant disease, previous chemotherapy, and male gender were associated with lower hepatocyte viability and isolation cell yields. The previous increase in transaminases was also associated with lower yields on isolation and lower albumin production. Furthermore, ischemia secondary to vascular clamping during surgery was inversely correlated with the isolated hepatocyte viability. An ischemia time higher than 15 min was related to adverse effects on viability. Conclusion: Several factors correlated with the patient and the surgery directly influence the success of human hepatocyte isolation from patients undergoing liver resection.

Mortality and Causes of Death After Liver Transplantation: Analysis of Sex Differences in a Large Nationwide Cohort.

In the last few years, several studies have analyzed sex and gender differences in liver transplantation (LT), but none have performed a disaggregated analysis of both mortality and causes of death. Data from 15,998 patients, 11,914 (74.5%) males and 4,069 (25.5%) females, transplanted between 2000 and 2016 were obtained from the Liver Transplantation Spanish Registry. Survival analysis was applied to explore recipient sex as a risk factor for death. The causes of death at different follow-up duration were disaggregated by recipient sex for analysis. Short-term survival was higher in males, whereas long-term survival was higher in females. Survival at 1, 5 and 10 years post-transplant was 87.43%, 73.83%, and 61.23%, respectively, in males and 86.28%, 74.19%, and 65.10%, respectively, in females (p = 0.05). Post-LT mortality related to previous liver disease also presented sex differences. Males had 37% increased overall mortality from acute liver failure (p = 0.035) and 37% from HCV-negative cirrhosis (p < 0.001). Females had approximately 16% increased mortality when the liver disease was HCV-positive cirrhosis (p = 0.003). Regarding causes of death, non-malignancy HCV+ recurrence (6.3% vs. 3.9% of patients; p < 0.001), was more frequently reported in females. By contrast, death because of malignancy recurrence (3.9% vs. 2.2% of patients; p = 0.003) and de novo malignancy (4.8% vs. 2.5% of patients; p < 0.001) were significantly more frequent in male recipients. Cardiovascular disease, renal failure, and surgical complications were similar in both. In summary, male patients have lower short-term mortality than females but higher long-term and overall mortality. In addition, the post-LT mortality risk related to previous liver disease and the causes of mortality differ between males and females.

Cumulative exposure to tacrolimus and incidence of cancer after liver transplantation.

Cancer is the leading cause of death after liver transplantation (LT). This multicenter case-control nested study aimed to evaluate the effect of maintenance immunosuppression on post-LT malignancy. The eligible cohort included 2495 LT patients who received tacrolimus-based immunosuppression. After 13 922 person/years follow-up, 425 patients (19.7%) developed malignancy (cases) and were matched with 425 controls by propensity score based on age, gender, smoking habit, etiology of liver disease, and hepatocellular carcinoma (HCC) before LT. The independent predictors of post-LT malignancy were older age (HR = 1.06 [95% CI 1.05-1.07]; p < .001), male sex (HR = 1.50 [95% CI 1.14-1.99]), smoking habit (HR = 1.96 [95% CI 1.42-2.66]), and alcoholic liver disease (HR = 1.53 [95% CI 1.19-1.97]). In selected cases and controls (n = 850), the immunosuppression protocol was similar (p = .51). An increased cumulative exposure to tacrolimus (CET), calculated by the area under curve of trough concentrations, was the only immunosuppression-related predictor of post-LT malignancy after controlling for clinical features and baseline HCC (CET at 3 months p = .001 and CET at 12 months p = .004). This effect was consistent for de novo malignancy (after excluding HCC recurrence) and for internal neoplasms (after excluding non-melanoma skin cancer). Therefore, tacrolimus minimization, as monitored by CET, is the key to modulate immunosuppression in order to prevent cancer after LT.

In Vitro Methods to Decipher the Structure of Viral RNA Genomes.

RNA viruses encode essential information in their genomes as conserved structural elements that are involved in efficient viral protein synthesis, replication, and encapsidation. These elements can also establish complex networks of RNA-RNA interactions, the so-called RNA interactome, to shape the viral genome and control different events during intracellular infection. In recent years, targeting these conserved structural elements has become a promising strategy for the development of new antiviral tools due to their sequence and structural conservation. In this context, RNA-based specific therapeutic strategies, such as the use of siRNAs have been extensively pursued to target the genome of different viruses. Importantly, siRNA-mediated targeting is not a straightforward approach and its efficiency is highly dependent on the structure of the target region. Therefore, the knowledge of the viral structure is critical for the identification of potentially good target sites. Here, we describe detailed protocols used in our laboratory for the in vitro study of the structure of viral RNA genomes. These protocols include DMS (dimethylsulfate) probing, SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension) analysis, and HMX (2'-hydroxyl molecular interference). These methodologies involve the use of high-throughput analysis techniques that provide extensive information about the 3D folding of the RNA under study and the structural tuning derived from the interactome activity. They are therefore a good tool for the development of new RNA-based antiviral compounds.