New Insights About Albumin and Liver Disease.

Decompensated liver cirrhosis has a dismal prognosis, with an overall survival of 2-4 years, which is worse than for many oncological diseases. Albumin is an important tool in the management of patients with cirrhosis, since it decreases for less than half the risk for post-paracentesis cardiocirculatory dysfunction and mortality associated with spontaneous bacterial infection, as well as, it triplicates the response to terlipressin in patients with hepatorenal syndrome. Recently, research on albumin has been a hot topic, with important new insights such as the characterization of the pleiotropic effects of albumin (which surpass its oncotic properties) and the concept of effective albumin concentration. In fact, patients with liver cirrhosis present posttranslational modifications on albumin that compromises its function. Those modified albumin forms were proved to have prognostic value and its knowledge may change the paradigm of albumin treatment. In this review, we critically summarize the latest evidence on the potential benefits of albumin in patients with end-stage liver disease.

Exploiting Kinetic Features of ORAC Assay for Evaluation of Radical Scavenging Capacity.

The analysis and interpretation of data retrieved from Oxygen Radical Absorbance Capacity (ORAC) assays represent a challenging task. ORAC indexes originate from different mathematical approaches often lacking correct elucidation of kinetic features concerning radical scavenging reactions by antioxidant compounds. In this work, the expression of ORAC values as area under fluorescein (FL) decay curves (AUC) and lag time are critically compared. This multi-parametric analysis showed the extension of radical scavenging reactions beyond the lag time period for caffeic acid, gallic acid, reduced glutathione and quercetin, extending their antioxidant protection of FL. Ethanol delayed the reaction of both FL and antioxidant compounds with free radical species generated from 2,2'-azobis(2-amidinopropane) dihydrochloride thermolysis. Trolox equivalent values, commonly used to express ORAC values, were more affected by the differences in radical scavenging kinetics between the reference and the tested antioxidant compounds when calculated from AUC than from lag time. These findings stressed the importance of choosing calibrator compounds presenting ORAC kinetics similar to samples to prevent biased estimation of the antioxidant capacity. Additionally, the framework proposed here provides a sustainable analytical method for the evaluation of antioxidant capacity, with an AGREE score of 0.73.

Non-canonical Wnt signaling regulates junctional mechanocoupling during angiogenic collective cell migration.

Morphogenesis of hierarchical vascular networks depends on the integration of multiple biomechanical signals by endothelial cells, the cells lining the interior of blood vessels. Expansion of vascular networks arises through sprouting angiogenesis, a process involving extensive cell rearrangements and collective cell migration. Yet, the mechanisms controlling angiogenic collective behavior remain poorly understood. Here, we show this collective cell behavior is regulated by non-canonical Wnt signaling. We identify that Wnt5a specifically activates Cdc42 at cell junctions downstream of ROR2 to reinforce coupling between adherens junctions and the actin cytoskeleton. We show that Wnt5a signaling stabilizes vinculin binding to alpha-catenin, and abrogation of vinculin in vivo and in vitro leads to uncoordinated polarity and deficient sprouting angiogenesis in Mus musculus. Our findings highlight how non-canonical Wnt signaling coordinates collective cell behavior during vascular morphogenesis by fine-tuning junctional mechanocoupling between endothelial cells.

Acute pancreatitis in the elderly: a cause for increased concern?

BACKGROUND: Acute pancreatitis (AP) is an aggressive and potentially fatal clinical condition. Although all age groups are at risk, the elderly may be a group of special concern. We aimed at evaluating clinical outcomes of patients with elderly-onset AP. MATERIALS AND METHODS: Using a single-center retrospective database, treatment and follow-up records of 550 patients admitted with AP were reviewed. Outcomes included mortality, admission to the ICU, need for interventional procedures, nutritional support, and length of hospital and ICU stay. Elderly-onset AP was defined as an episode of AP occurring in patients older than 65 years. RESULTS: A total of 263 patients were classified as having elderly-onset AP. There was an association between older age and higher Ranson and the bedside index of severity in AP scores, translating into longer lengths of hospital stay, higher requirements for ICU admission, interventional procedures, organ failure, persistent organ failure, and overall mortality. In multivariate analysis, age was an independent predictor of mortality in AP. CONCLUSIONS: Age was strongly associated with a more severe course of AP. Early recognition and prompt action are essential to improve outcomes in this population.

Signet Ring Cell Carcinoma, Ileal Crohn Disease or Both? - A Case of Diagnostic Challenge.

Signet ring cell carcinoma is a rare form of adenocarcinoma that predominantly affects the stomach. Signet ring cell carcinoma originated from the ileum is extremely rare and the prognosis is poor. We present a case of small bowel obstruction with features suggesting Crohn disease of the ileum. The symptoms were chronic diarrhea and abdominal pain with a family history of inflammatory bowel disease. The patient underwent surgery and histopathology revealed both aspects of signet ring cell carcinoma and Crohn disease of the ileum. An association between long-standing inflammation and the development of this subtype of tumor has been proposed but there are no established surveillance guidelines for small bowel neoplasm in inflammatory bowel disease.

O carcinoma de células em anel de sinete é uma forma rara de adenocarcinoma que afeta predominantemente o estômago. A forma primária do íleon é muito rara e apresenta mau prognóstico. Apresentamos um caso de doença de Crohn do íleon cuja forma de apresentação cursou com quadro oclusivo associado a adenocarcinoma de células em anel de sinete do íleon. A doente apresentava história prévia de diarreia crónica e tinha história familiar de doença inflamatória. Foi submetida a ressecção cirúrgica e os achados histopatológicos revelaram a presença de aspetos compatíveis com doença de Crohn do íleon e adenocarcinoma de células em anel de sinete. Foi proposta uma associação com esta forma rara de tumor e inflamação de longa duração, contudo, não existem recomendações estabelecidas de vigilância de neoplasia na doença inflamatória intestinal com atingimento ileal.

YAP and TAZ regulate adherens junction dynamics and endothelial cell distribution during vascular development.

Formation of blood vessel networks by sprouting angiogenesis is critical for tissue growth, homeostasis and regeneration. How endothelial cells arise in adequate numbers and arrange suitably to shape functional vascular networks is poorly understood. Here we show that YAP/TAZ promote stretch-induced proliferation and rearrangements of endothelial cells whilst preventing bleeding in developing vessels. Mechanistically, YAP/TAZ increase the turnover of VE-Cadherin and the formation of junction associated intermediate lamellipodia, promoting both cell migration and barrier function maintenance. This is achieved in part by lowering BMP signalling. Consequently, the loss of YAP/TAZ in the mouse leads to stunted sprouting with local aggregation as well as scarcity of endothelial cells, branching irregularities and junction defects. Forced nuclear activity of TAZ instead drives hypersprouting and vascular hyperplasia. We propose a new model in which YAP/TAZ integrate mechanical signals with BMP signaling to maintain junctional compliance and integrity whilst balancing endothelial cell rearrangements in angiogenic vessels.

Predicting short-term and long-term mortality of hospitalized Portuguese patients with alcoholic hepatitis.

BACKGROUND: Alcohol abuse can result in a spectrum of liver injury that ranges from mild fatty infiltration to alcoholic hepatitis (AH), cirrhosis, and hepatocellular carcinoma. The present study aimed to evaluate current scoring systems in predicting short-term and long-term mortality because of AH. PATIENTS AND METHODS: Records of 170 consecutive patients with AH admitted to a tertiary center between January 2005 and October 2015 were reviewed. Clinical and biochemical parameters were retrieved for the assessment of AH scores for the day of admission (D1) and for the seventh day of hospitalization (D7). Endpoints included admission to the ICU, and 30-day, 90-day, and 1-year mortality. RESULTS: The Maddrey discriminant function and the Model of End-Stage Liver Disease (MELD) were modest predictors of the need for ICU admission. In-hospital, 30-day, 90-day, and 1-year mortality were 15.9, 18.2, 21.8, and 30.0%, respectively. There was a numerical, albeit nonsignificant, trend for higher accuracy using D7 scores, especially the MELD, in predicting 30-day and 1-year mortality. Overall, all scores showed high negative predictive values (30 day: 91.2-98.7% and 1 year: 78.8-93.7%), but modest positive predictive values (30 day: 30.6-70.8% and 1 year: 42.1-61.2%). Survival rates were the highest among patients showing a decrease in the MELD, Glasgow Alcoholic Hepatitis Score, and Age, serum Bilirubin, International normalized ratio, and serum Creatinine score over the first week of admission. DISCUSSION: AH scores were comparable in identifying patients at low risk of mortality up to 1 year following admission. Reassessment of the MELD, Glasgow Alcoholic Hepatitis Score, and Age, serum Bilirubin, International normalized ratio, and serum Creatinine score scores after 1 week further improved mortality prediction.

Development and validation of a liquid chromatography-MS/MS method for simultaneous quantification of tenofovir and efavirenz in biological tissues and fluids.

Millions of people worldwide live with human immunodeficiency virus (HIV) infection thus justifying the continuous search for new prevention and treatment strategies, including topical microbicide products combining antiretroviral drugs (ARVs) such as tenofovir (TFV) and efavirenz (EFV). Therefore, the aim of this work was to develop and validate a high performance liquid chromatography method coupled to triple quadrupole-tandem mass spectrometry (HPLC-MS/MS) for the quantification of TFV and EFV in biological matrices (mouse vaginal tissue, vaginal lavage and blood plasma). Chromatographic separation was achieved using a reversed phase C18 column (3µm, 100×2.1mm) at 45°C and elution in gradient mode using a combination of 0.1% (v/v) formic acid in water and 0.1% (v/v) formic acid in acetonitrile at 0.35mLmin-1. Total run time was 9min, with retention time of 2.8 and 4.1min for TFV and EFV, respectively. The MS was operated in positive ionization mode (ESI+) for TFV and in negative ionization mode (ESI-) for EFV detection. Data were acquired in selected reaction monitoring (SRM) mode and deuterated ARVs were employed as internal standards. Calibration curves were linear for ARV concentrations ranging from 4 to 500ngmL-1 with LOD and LOQ for both analytes ≤0.4 and ≤0.7ngmL-1 in sample extracts, respectively. The method was found to be specific, accurate (96.0-106.0% of nominal values) and precise (RSD<2.4%) in all matrices. Both TFV and EFV were found to be stable in all matrices after standing 24h at room temperature (20°C) or in the autosampler, and after three freeze-thawing cycles. Mean recovery values of ARVs spiked in mice tissues or fluids were ≥88.4%. Matrix effects were observed for EFV determination in tissue and plasma extracts but compensated by the use of deuterated internal standards. The proposed methodology was successfully applied to a pharmacokinetic study following intravaginal administration of both ARVs.

Endothelial cell dynamics in vascular remodelling.

In this ESCHM 2016 conference talk report, we summarise two recently published original articles Franco et al. PLoS Biology 2015 and Franco et al. eLIFE 2016. The vascular network undergoes extensive vessel remodelling to become fully functional. Is it well established that blood flow is a main driver for vascular remodelling. It has also been proposed that vessel pruning is a central process within physiological vessel remodelling. However, despite its central function, the cellular and molecular mechanisms regulating vessel regression, and their interaction with blood flow patterns, remain largely unexplained. We investigated the cellular process governing developmental vascular remodelling in mouse and zebrafish. We established that polarised reorganization of endothelial cells is at the core of vessel regression, representing vessel anastomosis in reverse. Moreover, we established for the first time an axial polarity map for all endothelial cells together with an in silico method for the computation of the haemodynamic forces in the murine retinal vasculature. Using network-level analysis and microfluidics, we showed that endothelial non-canonical Wnt signalling regulates endothelial sensitivity to shear forces. Loss of Wnt5a/11 renders endothelial cells more sensitive to shear, resulting in axial polarisation at lower shear stress levels. Collectively our data suggest that non-canonical Wnt signalling stabilizes forming vascular networks by reducing endothelial shear sensitivity, thus keeping vessels open under low flow conditions that prevail in the primitive plexus.