Outcomes of elective liver surgery worldwide: a global, prospective, multicenter, cross-sectional study

Background: The outcomes of liver surgery worldwide remain unknown. The true population-based outcomes are likely different to those vastly reported that reflect the activity of highly specialized academic centers. The aim of this study was to measure the true worldwide practice of liver surgery and associated outcomes by recruiting from centers across the globe. The geographic distribution of liver surgery activity and complexity was also evaluated to further understand variations in outcomes. Methods: LiverGroup.org was an international, prospective, multicenter, cross-sectional study following the Global Surgery Collaborative Snapshot Research approach with a 3-month prospective, consecutive patient enrollment within January–December 2019. Each patient was followed up for 90 days postoperatively. All patients undergoing liver surgery at their respective centers were eligible for study inclusion. Basic demographics, patient and operation characteristics were collected. Morbidity was recorded according to the Clavien–Dindo Classification of Surgical Complications. Country-based and hospital-based data were collected, including the Human Development Index (HDI). (NCT03768141). Results: A total of 2159 patients were included from six continents. Surgery was performed for cancer in 1785 (83%) patients. Of all patients, 912 (42%) experienced a postoperative complication of any severity, while the major complication rate was 16% (341/2159). The overall 90-day mortality rate after liver surgery was 3.8% (82/2,159). The overall failure to rescue rate was 11% (82/ 722) ranging from 5 to 35% among the higher and lower HDI groups, respectively. Conclusions: This is the first to our knowledge global surgery study specifically designed and conducted for specialized liver surgery. The authors identified failure to rescue as a significant potentially modifiable factor for mortality after liver surgery, mostly related to lower Human Development Index countries. Members of the LiverGroup.org network could now work together to develop quality improvement collaboratives

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Study of the signal transduction from the TNF receptors and characterization of USP31

The tumor necrosis factor superfamily of cytokines and receptors (TNF/TNFR) activate signalling pathways for cell proliferation, differentiation and apoptosis. CD40 Receptor is a member of the Tumor Necrosis Factor Receptors (TNFR) and is expressed mainly on the surface of B lymphocytes. CD40 interacts with CD40 Ligand (CD154) which is expressed mainly on T lymphocytes. LMP1 is a pseudoreceptor of the TNFR superfamily which mimics CD40 signalling and is constitutively activated. TRAFs constitute a family of proteins that participate in signal transduction by members of the TNF receptor superfamily. The amino terminal region of TRAFs is rich in cysteine and histidine residues, arranged in putative zinc-finger motifs and a more complex RING finger motif. TRAF2 and TRAF6 have a ubiquitin ligase activity which is dependent on the integrity of their RING finger domain and has been associated with the ability to activate the NF-κB and AP1 signalling pathways. Protein modification by ubiquitination has been primarily associated with degradation by the proteasome. However, protein ubiquitination has also been implicated in other cellular functions, including cell cycle regulation, signal transduction, transcription regulation, receptor endocytosis, ribosomal function etc. In previous studies of our research team, a yeast two-hybrid screening was performed in order to elucidate further the TRAF2 signalling mechanism. One of the isolated proteins demonstrated a strong positive interaction with wild type TRAF2, but very weak or no interaction with a mutant TRAF2 at the RING finger domain. This protein was studied further and turned out to be identical to a ubiquitin specific protease named USP31. Comparison of the USP31 cDNA sequence with human ESTs revealed that at least two USP31 cDNAs exist. One cDNA encodes for a 1035-amino-acid long polypeptide (USP31, long isoform) whereas the other encodes for a 485-amino-acid long polypeptide (short isoform, USP31S1). The two isoforms of USP31 share a common amino terminal region of 483 amino acids and contain all eight characteristic motifs of known deubiquitinases. Northern blot analysis of normal tissues and cancer cell lines revealed two major mRNA species of approximately 4.4 and 2.4 kb. The 4.4 kb mRNA was expressed in all normal tissues and cancer cell lines tested, while the 2.4 kb mRNA was expressed only in cancer cell lines. These mRNAs are likely to be derived from alternative splicing and may code for USP31 and USP31S1 respectively. USP31 was examined for its ability to act as a ubiquitin specific protease (USP/UBP). In addition to wild type USP31, a point mutant containing a serine instead of cysteine at position 98 (USP31C98S) was constructed and tested for its enzymatic activity. Cysteine-98 corresponds to a highly conserved cysteine of the catalytic domain of deubiquitinating enzymes (Cys box). USP31, USP31C98S and USP31S1 were tested for their ability to cleave tetraubiquitin in vitro. Wild type full length USP31 readily cleaved the tetrameric substrate to its monomer, dimer and trimer. However, the point mutant USP31C98S and the short isoform USP31S1 were enzymatically inactive. Furthermore, USP31 was tested for its deubiquitinating specificity towards lysine-48 or lysine-63-linked polyubiquitin chains. Lysine-48-linked polyubiquitin chains usually mark proteins for proteasomal degradation whereas lysine-63-linked polyubiquitin chains have been associated primarily with non-proteolytic regulatory processes. Wild type USP31 cleaved almost completely lysine-63-linked polyubiquitin. Moreover, it cleaved partially lysine-48-linked polyubiquitin. The point mutant USP31C98S or the short isoform USP31S1 did not cleave any of the two substrates. These results demonstrate that USP31 is a deubiquitinating enzyme that cleaves preferentially lysine-63-linked polyubiquitin chains. USP31 can also cleave lysine-48-linked polyubiquitin chains albeit to a lesser extent. The ability of USP31 to interact with TRAF2 in mammalian cells was tested by co-immunoprecipitation experiments in HEK 293T cells. These experiments confirmed the specific interaction of USP31 and TRAF2 which requires an intact RING finger domain of TRAF2. Indirect immunofluorescense showed that USP31 is localized predominantly in the nucleus and to some extent in the cytoplasm. .................................................................................................Tα μέλη της υπεροικογένειας των κυτοκινών και των υποδοχέων του παράγοντα νέκρωσης όγκων (TNF/TNFR) ενεργοποιούν μονοπάτια μεταγωγής σήματος για τον κυτταρικό πολλαπλασιασμό, τη διαφοροποίηση και την απόπτωση. Ο υποδοχέας CD40 είναι μέλος της οικογένειας των υποδοχέων TNFR και εκφράζεται κυρίως σε Β-λεμφοκύτταρα. Αλληλεπιδρά με τον συνδέτη CD40L (CD154), ο οποίος εκφράζεται κυρίως σε Τ-λεμφοκύτταρα. Η πρωτεΐνη LMP1 είναι ένας «ψευδοϋποδοχέας» της υπεροικογένειας TNFR, που μιμείται τη μεταγωγή σήματος από τον υποδοχέα CD40 και είναι συνεχώς ενεργoποιημένος. Oι πρωτεΐνες ΤRAF συμμετέχουν στη μεταγωγή σήματος από τους υποδοχείς της υπεροικογένειας TNFR. Η αμινοτελική περιοχή των πρωτεϊνών TRAF είναι πλούσια σε κυστεΐνη και ιστιδίνη, οι οποίες συγκροτούν δομές δακτυλίων ψευδαργύρου καθώς και μια πιο σύνθετη δομή που ονομάζεται RING Finger. Οι πρωτεΐνες TRAF2 και TRAF6 έχουν ενζυμική δράση λιγάσης της ουβικιτίνης, η οποία εξαρτάται από την ακεραιότητα της δομής RING Finger και σχετίζεται με την ικανότητά τους να ενεργοποιούν τους μεταγραφικούς παράγοντες NF-κΒ και AP1. H ουβικιτίνωση των πρωτεϊνών είναι μια μετά-μεταφραστική τροποποίηση, η οποία έχει συσχετιστεί πρωταρχικά με την αποικοδόμηση από το πρωτεάσωμα. Ωστόσο, η ουβικιτίνωση εμπλέκεται και σε άλλες κυτταρικές λειτουργίες, όπως η ρύθμιση του κυτταρικού κύκλου, η μεταγωγή σήματος, η ρύθμιση της μεταγραφής, η ενδοκυττάρωση υποδοχέων, η λειτουργία των ριβοσωμάτων κ.α. Σε προηγούμενες μελέτες της ερευνητικής μας ομάδας, έγινε χρήση της τεχνικής των δύο υβριδίων στο σακχαρομύκητα, προκειμένου να διερευνηθεί περαιτέρω ο μηχανισμός μεταγωγής σήματος από την πρωτεΐνη TRAF2. Με τη βοήθεια της τεχνικής των δύο υβριδίων απομονώθηκε μια πρωτεΐνη, η οποία παρουσιάζει ισχυρή θετική αλληλεπίδραση με την «άγριου τύπου» πρωτεΐνη TRAF2. Αντίθετα, δεν αλληλεπιδρά με μια μεταλλαγμένη μορφή της πρωτεΐνης TRAF2, ως προς στην περιοχή RING Finger. Η συγκεκριμένη πρωτεΐνη μελετήθηκε περαιτέρω και αποδείχτηκε ότι ταυτίζεται με μια ειδική πρωτεάση της ουβικιτίνης που ονομάζεται USP31 (Ubiquitin Specific Protease 31). Η σύγκριση του cDNA της πρωτεΐνης USP31 με αλληλουχίες cDNA του ανθρώπου από βάσεις δεδομένων (ESTs) αποκάλυψε την ύπαρξη τουλάχιστον δύο cDNA για την πρωτεΐνη USP31. Το ένα cDNA κωδικοποιεί μια πρωτεΐνη 1035 αμινοξέων (USP31, μεγάλη ισομορφή), ενώ το δεύτερο κωδικοποιεί μια πρωτεΐνη 485 αμινοξέων (USP31S1, μικρή ισομορφή). Οι δύο ισομορφές έχουν κοινή αμινοτελική περιοχή 483 αμινοξέων και περιέχουν και τα οκτώ χαρακτηριστικά μοτίβα των γνωστών ενζύμων αποουβικιτίνωσης. Ο υβριδισμός τύπου Northern που έγινε τόσο σε φυσιολογικούς ιστούς, όσο και σε καρκινικές κυτταρικές σειρές, αποκάλυψε την ύπαρξη δύο mRNA μεγέθους 4,4 και 2,4 χιλιάδων βάσεων. To mRNA μεγέθους 4,4 χιλιάδων βάσεων ανιχνεύθηκε σε όλους τους ιστούς και τις καρκινικές κυτταρικές σειρές που δοκιμάστηκαν. To mRNA μεγέθους 2,4 χιλιάδων βάσεων ανιχνεύθηκε μόνο σε καρκινικά κύτταρα. Τα συγκεκριμένα mRNA μπορεί να προκύπτουν με εναλλακτική διασύνδεση (alternative splicing) και μπορεί να κωδικοποιούν αντίστοιχα τη μεγάλη (USP31) και τη μικρή ισομορφή (USP31S1). Η πρωτεΐνη USP31 εξετάστηκε ως προς την ικανότητά της να δρα ως ειδική πρωτεάση της ουβικιτίνης (USP/UBP). Για το σκοπό αυτό, κατασκευάστηκε επιπλέον μια μεταλλαγμένη πρωτεΐνη (USP31C98S), στην οποία η κυστεΐνη στη θέση 98 έχει αντικατασταθεί από το αμινοξύ σερίνη. Η κυστεΐνη-98 αντιστοιχεί σε μια ιδιαίτερα διατηρημένη κυστεΐνη της καταλυτικής περιοχής («κουτί» κυστεΐνης). Η πρωτεΐνη USP31, η μετάλλαξη USP31C98S και η μικρή ισομορφή USP31S1 εξετάστηκαν ως προς την ικανότητά τους να υδρολύουν το υπόστρωμα της τετραουβικιτίνης in vitro. Η πρωτεΐνη USP31 υδρολύει το τετραμερές υπόστρωμα στα μονομερή, διμερή και τριμερή ουβικιτίνης αντίστοιχα. Αντίθετα, οι πρωτεΐνες USP31C98S και USP31S1 είναι ενζυμικά ανενεργές. Επιπρόσθετα, διερευνήθηκε η εξειδίκευση της ενζυμικής δράσης της πρωτεΐνης USP31, απέναντι σε αλυσίδες πολυουβικιτίνης που συνδέονται μέσω της λυσίνης-48, ή της λυσίνης-63, κάθε μορίου ουβικιτίνης. ......................................................................................................................................

Biofilm Formation on Hybrid, Resin-Based CAD/CAM Materials for Indirect Restorations: A Comprehensive Review

Hybrid materials are a recent addition in the field of restorative dentistry for computer-aided design/computer-aided manufacturing (CAD/CAM) indirect restorations. The long-term clinical success of modern dental restorative materials is influenced by multiple factors. Among the characteristics affecting the longevity of a restoration, the mechanical properties and physicοchemical interactions are of utmost importance. While numerous researchers constantly evaluate mechanical properties, the biological background of resin-based CAD/CAM biomaterials is scarcely investigated and, therefore, less described in the literature. This review aims to analyze biofilm formation on the surfaces of novel, hybrid, resin-based CAD/CAM materials and evaluate the methodological protocols followed to assess microbial growth. It is demonstrated that the surface structure, the composition and the finishing and polishing procedures on the surface of a dental restorative material influence initial bacterial adhesion; however, most studies focus on in vitro protocols, and in vivo and/or in situ research of microbiomics in CAD/CAM restorative materials is lacking, obstructing an accurate understanding of the bioadhesion phenomenon in the oral cavity

Prolactin Inhibits Activity of Pyruvate Kinase M2 to Stimulate Cell Proliferation

Mitogenic and prosurvival effects underlie the tumorigenic roles of prolactin (PRL) in the pathogenesis of breast cancer. PRL signaling is mediated through its receptor (PRLr). A proteomics screen identified the pyruvate kinase M2 (PKM2), a glycolytic enzyme known to play an important role in tumorigenesis, as a protein that constitutively interacts with PRLr. Treatment of cells with PRL inhibited pyruvate kinase activity and increased the lactate content in human cells in a manner that was dependent on the abundance of PRLr, activation of Janus kinase 2, and tyrosine phosphorylation of the intracellular domain of PRLr. Knockdown of PKM2 attenuated PRL-stimulated cell proliferation. The extent of this proliferation was rescued by the knock-in of the wild-type PKM2 but not of its mutant insensitive to PRL-mediated inhibition. We discuss a hypothesis that the inhibition of PKM2 by PRL contributes to the PRL-stimulated cell proliferation

WIPI1 is a conserved mediator of right ventricular failure

Right ventricular dysfunction is highly prevalent across cardiopulmonary diseases and independently predicts death in both heart failure (HF) and pulmonary hypertension (PH). Progression towards right ventricular failure (RVF) can occur in spite of optimal medical treatment of HF or PH, highlighting current insufficient understanding of RVF molecular pathophysiology. To identify molecular mechanisms that may distinctly underlie RVF, we investigated the cardiac ventricular transcriptome of advanced HF patients, with and without RVF. Using an integrated systems genomic and functional biology approach, we identified an RVF-specific gene module, for which WIPI1 served as a hub and HSPB6 and MAP4 as drivers, and confirmed the ventricular specificity of Wipi1, Hspb6, and Map4 transcriptional changes in adult murine models of pressure overload induced RV- versus LV- failure. We uncovered a shift towards non-canonical autophagy in the failing RV that correlated with RV-specific Wipi1 upregulation. In vitro siRNA silencing of Wipi1 in neonatal rat ventricular myocytes limited non-canonical autophagy and blunted aldosterone-induced mitochondrial superoxide levels. Our findings suggest that Wipi1 regulates mitochondrial oxidative signaling and non-canonical autophagy in cardiac myocytes. Together with our human transcriptomic analysis and corroborating studies in an RVF mouse model, these data render Wipi1 a potential target for RV-directed HF therapy

A novel role for phospholamban in the thalamic reticular nucleus

Abstract The thalamic reticular nucleus (TRN) is a brain region that influences vital neurobehavioral processes, including executive functioning and the generation of sleep rhythms. TRN dysfunction underlies hyperactivity, attention deficits, and sleep disturbances observed across various neurodevelopmental disorders. A specialized sarco-endoplasmic reticulum calcium (Ca2+) ATPase 2 (SERCA2)-dependent Ca2+ signaling network operates in the dendrites of TRN neurons to regulate their bursting activity. Phospholamban (PLN) is a prominent regulator of SERCA2 with an established role in myocardial Ca2 +-cycling. Our findings suggest that the role of PLN extends beyond the cardiovascular system to impact brain function. Specifically, we found PLN to be expressed in TRN neurons of the adult mouse brain, and utilized global constitutive and innovative conditional genetic knockout mouse models in concert with electroencephalography (EEG)-based somnography and the 5-choice serial reaction time task (5-CSRTT) to investigate the role of PLN in sleep and executive functioning, two complex behaviors that map onto thalamic reticular circuits. The results of the present study indicate that perturbed PLN function in the TRN results in aberrant TRN-dependent phenotypes in mice (i.e., hyperactivity, impulsivity and sleep deficits) and support a novel role for PLN as a critical regulator of SERCA2 in the TRN neurocircuitry