EXD2 governs germ stem cell homeostasis and lifespan by promoting mitoribosome integrity and translation

Mitochondria are subcellular organelles critical for meeting the bioenergetic and biosynthetic needs of the cell. Mitochondrial function relies on genes and RNA species encoded both in the nucleus and mitochondria, as well as their coordinated translation, import and respiratory complex assembly. Here we describe the characterization of exonuclease domain like 2 (EXD2), a nuclear encoded gene that we show is targeted to the mitochondria and prevents the aberrant association of mRNAs with the mitochondrial ribosome. The loss of EXD2 resulted in defective mitochondrial translation, impaired respiration, reduced ATP production, increased reactive oxygen species and widespread metabolic abnormalities. Depletion of EXD2/CG6744 in D.melanogaster caused developmental delays and premature female germline stem cell attrition, reduced fecundity and a dramatic extension of lifespan that could be reversed with an anti-oxidant diet. Our results define a conserved role for EXD2 in mitochondrial translation that influences development and aging

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Surgery for Bismuth-Corlette Type 4 Perihilar Cholangiocarcinoma:Results from a Western Multicenter Collaborative Group

Contains fulltext : 239075.pdf (Publisher’s version ) (Open Access)BACKGROUND: Although Bismuth-Corlette (BC) type 4 perihilar cholangiocarcinoma (pCCA) is no longer considered a contraindication for curative surgery, few data are available from Western series to indicate the outcomes for these patients. This study aimed to compare the short- and long-term outcomes for patients with BC type 4 versus BC types 2 and 3 pCCA undergoing surgical resection using a multi-institutional international database. METHODS: Uni- and multivariable analyses of patients undergoing surgery at 20 Western centers for BC types 2 and 3 pCCA and BC type 4 pCCA. RESULTS: Among 1138 pCCA patients included in the study, 826 (73%) had BC type 2 or 3 disease and 312 (27%) had type 4 disease. The two groups demonstrated significant differences in terms of clinicopathologic characteristics (i.e., portal vein embolization, extended hepatectomy, and positive margin). The incidence of severe complications was 46% for the BC types 2 and 3 patients and 51% for the BC type 4 patients (p = 0.1). Moreover, the 90-day mortality was 13% for the BC types 2 and 3 patients and 12% for the BC type 4 patients (p = 0.57). Lymph-node metastasis (N1; hazard-ratio [HR], 1.62), positive margins (R1; HR, 1.36), perineural invasion (HR, 1.53), and poor grade of differentiation (HR, 1.25) were predictors of survival (all p ≤0.004), but BC type was not associated with prognosis. Among the N0 and R0 patients, the 5-year overall survival was 43% for the patients with BC types 2 and 3 pCCA and 41% for those with BC type 4 pCCA (p = 0.60). CONCLUSIONS: In this analysis of a large Western multi-institutional cohort, resection was shown to be an acceptable curative treatment option for selected patients with BC type 4 pCCA although a more technically challenging surgical approach was required

Simultaneous resection of colorectal cancer and synchronous liver metastases: what determines the risk of unfavorable outcomes? An international multicenter retrospective cohort study

BACKGROUND: The use of a simultaneous resection (SIMR) in patients with synchronous colorectal liver metastases (sCRLM) has increased over the past decades. However, it remains unclear when a SIMR is beneficial and when it should be avoided. The aim of this retrospective cohort study was therefore to compare the outcomes of a SIMR for sCRLM in different settings, and to assess which factors are independently associated with unfavorable outcomes. METHODS: To perform this retrospective cohort study, patients with sCRLM undergoing SIMR (2004-2019) were extracted from an international multicenter database, and their outcomes were compared after stratification according to the type of liver and colorectal resection performed. Factors associated with unfavorable outcomes were identified through multivariable logistic regression. RESULTS: Overall, 766 patients were included, encompassing colorectal resections combined with a major liver resection (n=122), minor liver resection in the anterolateral (n=407), or posterosuperior segments ('Technically major', n=237). Minor and technically major resections, compared to major resections, were more often combined with a rectal resection (29.2 and 36.7 vs. 20.5%, respectively, both P=0.003) and performed fully laparoscopic (22.9 and 23.2 vs. 6.6%, respectively, both P = 0.003). Major and technically major resections, compared to minor resections, were more often associated with intraoperative transfusions (42.9 and 38.8 vs. 20%, respectively, both P = 0.003) and unfavorable incidents (9.6 and 9.8 vs. 3.3%, respectively, both P≤0.063). Major resections were associated, compared to minor and technically major resections, with a higher overall morbidity rate (64.8 vs. 50.4 and 49.4%, respectively, both P≤0.024) and a longer length of stay (12 vs. 10 days, both P≤0.042). American Society of Anesthesiologists grades ≥3 [adjusted odds ratio (aOR): 1.671, P=0.015] and undergoing a major liver resection (aOR: 1.788, P=0.047) were independently associated with an increased risk of severe morbidity, while undergoing a left-sided colectomy was associated with a decreased risk (aOR: 0.574, P=0.013). CONCLUSIONS: SIMR should primarily be reserved for sCRLM patients in whom a minor or technically major liver resection would suffice and those requiring a left-sided colectomy. These findings should be confirmed by randomized studies comparing SIMR with staged resections

Portal Vein Embolization is Associated with Reduced Liver Failure and Mortality in High-Risk Resections for Perihilar Cholangiocarcinoma

Background Preoperative portal vein embolization (PVE) is frequently used to improve future liver remnant volume (FLRV) and to reduce the risk of liver failure after major liver resection. Objective This paper aimed to assess postoperative outcomes after PVE and resection for suspected perihilar cholangiocarcinoma (PHC) in an international, multicentric cohort. Methods Patients undergoing resection for suspected PHC across 20 centers worldwide, from the year 2000, were included. Liver failure, biliary leakage, and hemorrhage were classified according to the respective International Study Group of Liver Surgery criteria. Using propensity scoring, two equal cohorts were generated using matching parameters, i.e. age, sex, American Society of Anesthesiologists classification, jaundice, type of biliary drainage, baseline FLRV, resection type, and portal vein resection. Results A total of 1667 patients were treated for suspected PHC during the study period. In 298 patients who underwent preoperative PVE, the overall incidence of liver failure and 90-day mortality was 27% and 18%, respectively, as opposed to 14% and 12%, respectively, in patients without PVE (p &lt; 0.001 and p = 0.005). After propensity score matching, 98 patients were enrolled in each cohort, resulting in similar baseline and operative characteristics. Liver failure was lower in the PVE group (8% vs. 36%, p &lt; 0.001), as was biliary leakage (10% vs. 35%, p &lt; 0.01), intra-abdominal abscesses (19% vs. 34%, p = 0.01), and 90-day mortality (7% vs. 18%, p = 0.03). Conclusion PVE before major liver resection for PHC is associated with a lower incidence of liver failure, biliary leakage, abscess formation, and mortality. These results demonstrate the importance of PVE as an integral component in the surgical treatment of PHC

Surgery for Bismuth-Corlette Type 4 Perihilar Cholangiocarcinoma : Results from a Western Multicenter Collaborative Group

Background: Although Bismuth-Corlette (BC) type 4 perihilar cholangiocarcinoma (pCCA) is no longer considered a contraindication for curative surgery, few data are available from Western series to indicate the outcomes for these patients. This study aimed to compare the short- and long-term outcomes for patients with BC type 4 versus BC types 2 and 3 pCCA undergoing surgical resection using a multi-institutional international database. Methods: Uni- and multivariable analyses of patients undergoing surgery at 20 Western centers for BC types 2 and 3 pCCA and BC type 4 pCCA. Results: Among 1138 pCCA patients included in the study, 826 (73%) had BC type 2 or 3 disease and 312 (27%) had type 4 disease. The two groups demonstrated significant differences in terms of clinicopathologic characteristics (i.e., portal vein embolization, extended hepatectomy, and positive margin). The incidence of severe complications was 46% for the BC types 2 and 3 patients and 51% for the BC type 4 patients (p = 0.1). Moreover, the 90-day mortality was 13% for the BC types 2 and 3 patients and 12% for the BC type 4 patients (p = 0.57). Lymph-node metastasis (N1; hazard-ratio [HR], 1.62), positive margins (R1; HR, 1.36), perineural invasion (HR, 1.53), and poor grade of differentiation (HR, 1.25) were predictors of survival (all p ≤0.004), but BC type was not associated with prognosis. Among the N0 and R0 patients, the 5-year overall survival was 43% for the patients with BC types 2 and 3 pCCA and 41% for those with BC type 4 pCCA (p = 0.60). Conclusions: In this analysis of a large Western multi-institutional cohort, resection was shown to be an acceptable curative treatment option for selected patients with BC type 4 pCCA although a more technically challenging surgical approach was required

The Bicoid Stability Factor Controls Polyadenylation and Expression of Specific Mitochondrial mRNAs in Drosophila melanogaster

The bicoid stability factor (BSF) of Drosophila melanogaster has been reported to be present in the cytoplasm, where it stabilizes the maternally contributed bicoid mRNA and binds mRNAs expressed from early zygotic genes. BSF may also have other roles, as it is ubiquitously expressed and essential for survival of adult flies. We have performed immunofluorescence and cell fractionation analyses and show here that BSF is mainly a mitochondrial protein. We studied two independent RNAi knockdown fly lines and report that reduced BSF protein levels lead to a severe respiratory deficiency and delayed development at the late larvae stage. Ubiquitous knockdown of BSF results in a severe reduction of the polyadenylation tail lengths of specific mitochondrial mRNAs, accompanied by an enrichment of unprocessed polycistronic RNA intermediates. Furthermore, we observed a significant reduction in mRNA steady state levels, despite increased de novo transcription. Surprisingly, mitochondrial de novo translation is increased and abnormal mitochondrial translation products are present in knockdown flies, suggesting that BSF also has a role in coordinating the mitochondrial translation in addition to its role in mRNA maturation and stability. We thus report a novel function of BSF in flies and demonstrate that it has an important intra-mitochondrial role, which is essential for maintaining mtDNA gene expression and oxidative phosphorylation

Higher Postoperative Mortality and Inferior Survival After Right-Sided Liver Resection for Perihilar Cholangiocarcinoma: Left-Sided Resection is Preferred When Possible

Background: A right- or left-sided liver resection can be considered in about half of patients with perihilar cholangiocarcinoma (pCCA), depending on tumor location and vascular involvement. This study compared postoperative mortality and long-term survival of right- versus left-sided liver resections for pCCA. Methods: Patients who underwent major liver resection for pCCA at 25 Western centers were stratified according to the type of hepatectomy—left, extended left, right, and extended right. The primary outcomes were 90-day mortality and overall survival (OS). Results: Between 2000 and 2022, 1701 patients underwent major liver resection for pCCA. The 90-day mortality was 9% after left-sided and 18% after right-sided liver resection (p&nbsp;&lt;&nbsp;0.001). The 90-day mortality rates were 8% (44/540) after left, 11% (29/276) after extended left, 17% (51/309) after right, and 19% (108/576) after extended right hepatectomy (p&nbsp;&lt;&nbsp;0.001). Median OS was 30 months (95% confidence interval [CI] 27–34) after left and 23 months (95% CI 20–25) after right liver resection (p&nbsp;&lt;&nbsp;0.001), and 33 months (95% CI 28–38), 27 months (95% CI 23–32), 25 months (95% CI 21–30), and 21 months (95% CI 18–24) after left, extended left, right, and extended right hepatectomy, respectively (p&nbsp;&lt;&nbsp;0.001). A left-sided resection was an independent favorable prognostic factor for both 90-day mortality and OS compared with right-sided resection, with similar results after excluding 90-day fatalities. Conclusions: A left or extended left hepatectomy is associated with a lower 90-day mortality and superior OS compared with an (extended) right hepatectomy for pCCA. When both a left and right liver resection are feasible, a left-sided liver resection is preferred

An International Expert Delphi Consensus on Defining Textbook Outcome in Liver Surgery (TOLS)

Objective: To reach global expert consensus on the definition of TOLS in minimally invasive and open liver resection among renowned international expert liver surgeons using a modified Delphi method. Background: Textbook outcome is a novel composite measure combining the most desirable postoperative outcomes into one single measure and representing the ideal postoperative course. Despite a recently developed international definition of Textbook Outcome in Liver Surgery (TOLS), a standardized and expert consensus-based definition is lacking. Methods: This international, consensus-based, qualitative study used a Delphi process to achieve consensus on the definition of TOLS. The survey comprised 6 surgical domains with a total of 26 questions on individual surgical outcome variables. The process included 4 rounds of online questionnaires. Consensus was achieved when a threshold of at least 80% agreement was reached. The results from the Delphi rounds were used to establish an international definition of TOLS. Results: In total, 44 expert liver surgeons from 22 countries and all 3 major international hepato-pancreato-biliary associations completed round 1. Forty-two (96%), 41 (98%), and 41 (98%) of the experts participated in round 2, 3, and 4, respectively. The TOLS definition derived from the consensus process included the absence of intraoperative grade ≥2 incidents, postoperative bile leakage grade B/C, postoperative liver failure grade B/C, 90-day major postoperative complications, 90-day readmission due to surgery-related major complications, 90-day/in-hospital mortality, and the presence of R0 resection margin. Conclusions: This is the first study providing an international expert consensus-based definition of TOLS for minimally invasive and open liver resections by the use of a formal Delphi consensus approach. TOLS may be useful in assessing patient-level hospital performance and carrying out international comparisons between centers with different clinical practices to further improve patient outcomes