Anatomic patterns of anastomotic leaks after Ivor Lewis esophagectomy for cancer: Impact on management and outcomes.

BACKGROUND: Anastomotic leakage presentation after Ivor Lewis esophagectomy may vary on imaging. Such variations may influence anastomotic leakage management and outcomes. METHODS: All consecutive patients who underwent Ivor Lewis esophagectomy for cancer between 2012 and 2019 in 2 referral centers were included. Anatomical patterns of anastomotic leakage were defined on imaging as follows: eso-mediastinal anastomotic leakage was a leak contained in the posterior mediastinum, eso-pleural anastomotic leakage was a leak involving the pleural cavity, and eso-bronchial anastomotic leakage was a leak communicating with the tracheobronchial tract. According to the Esophageal Complications Consensus Group definition, management and 90-day mortality were evaluated according to these patterns. RESULTS: Among 731 patients, 111 (15%) developed anastomotic leakage consisting of eso-mediastinal anastomotic leakage (n = 87, 79%), eso-pleural anastomotic leakage (n = 16, 14%) and eso-bronchial anastomotic leakage (n = 8, 7%). There was no difference among these groups regarding preoperative characteristics or time to anastomotic leakage diagnosis. There was a significant difference in initial management according to anastomotic leakage anatomic patterns (P = .001). More than half of patients who experienced eso-mediastinal anastomotic leakage (n = 46, 53%) were initially treated conservatively without requiring intervention (Esophageal Complications Consensus Group type I), whereas most patients with eso-pleural anastomotic leakage (n = 14, 87.5%) and all with eso-bronchial anastomotic leakage (n = 8, 100%) initially required interventional or surgical treatment (Esophageal Complications Consensus Group type II-III). Anastomotic leakage anatomic patterns had a statistically significant impact on 90-day mortality, intensive care unit stay, and total hospital stay (P < .001). CONCLUSION: Anastomotic leakage anatomic patterns after Ivor Lewis esophagectomy influence outcomes. Further studies are warranted to validate it in a prospective setting. Anastomotic leakage anatomic patterns may help in guiding anastomotic leakage management.

A QTL on chromosome IV explains a natural variation of QR.pap final position in Caenorhabditis elegans.

In Caenorhabditis elegans , the QR neuroblast and its progeny migrate from the posterior to the anterior part of the animal during the L1 stage. We previously showed that the final position of QR.pa daughters varies among C. elegans wild isolates, with CB4932 displaying a particularly anterior QR.pap position (Dubois et al., 2021). Here, we study the genetic basis of the variation between isolates CB4932 and JU1242. We show that JU1242 alleles behave in a mostly dominant fashion. Using a Bulk Segregant Analysis, we detect a quantitative trait locus (QTL) region on chromosome IV. This QTL was confirmed using reciprocal chromosome IV introgressions.

Precise temporal control of neuroblast migration through combined regulation and feedback of a Wnt receptor.

Many developmental processes depend on precise temporal control of gene expression. We have previously established a theoretical framework for regulatory strategies that can govern such high temporal precision, but experimental validation of these predictions was still lacking. Here, we use the time-dependent expression of a Wnt receptor that controls neuroblast migration in Caenorhabditis elegans as a tractable system to study a robust, cell-intrinsic timing mechanism in vivo. Single-molecule mRNA quantification showed that the expression of the receptor increases non-linearly, a dynamic that is predicted to enhance timing precision over an unregulated, linear increase in timekeeper abundance. We show that this upregulation depends on transcriptional activation, providing in vivo evidence for a model in which the timing of receptor expression is regulated through an accumulating activator that triggers expression when a specific threshold is reached. This timing mechanism acts across a cell division that occurs in the neuroblast lineage and is influenced by the asymmetry of the division. Finally, we show that positive feedback of receptor expression through the canonical Wnt pathway enhances temporal precision. We conclude that robust cell-intrinsic timing can be achieved by combining regulation and feedback of the timekeeper gene.

Rapid electrochemical detection of Mycobacterium tuberculosis in sputum by measuring Ag85 activity with disposable carbon sensors.

An electrochemical assay for the detection of the enzymatic activity of the antigen 85 (Ag85) tuberculosis (TB) biomarker was developed and evaluated for the qualitative detection of Mycobacterium tuberculosis in decontaminated sputum. For this purpose, the electroactive properties of both synthetic p-aminophenyl-6-O-octanoyl-3-d-glucopyranoside (p-APOG) substrate and p-aminophenyl-6-3-d-glucopyranoside (p-APG) product released after the removal of the octanoyl fatty acid by the Ag85 were investigated with disposable carbon screen-printed electrodes by cyclic voltammetry. Since specific anodic responses were obtained for the p-APOG substrate and the p-APG product, the intensity of the oxidation peak of the p-APG (E = + 0.35 V vs. Ag/AgCl) was selected as the analytical response for the detection of the Ag85 acyltransferase activity. Once the proof of concept of the Ag85 electrochemical assay was validated with a commercially-available Ag85B protein, its specificity was further assessed by analyzing pure cultures of various bacteria including tuberculous and non-tuberculous mycobacteria as well as different species found in patients' sputum. Finally, with a specificity of 78% and a sensitivity of 89%, the method was successfully compared to microscopy and culture routine tests for TB testing in 36 frozen fluidized and decontaminated sputum. This suggests that owing to its convenience, rapidity, low-cost and portability, the reported Ag85 electrochemical assay is a promising tool to screen patients for TB.

Field Detection of Highly Oxygenated Organic Molecules in Shanghai by Chemical Ionization-Orbitrap.

Secondary organic aerosol, formed through atmospheric oxidation processes, plays an important role in affecting climate and human health. In this study, we conducted a comprehensive campaign in the megacity of Shanghai during the 2019 International Import Expo (EXPO), with the first deployment of a chemical ionization─Orbitrap mass spectrometer for ambient measurements. With the ultrahigh mass resolving power of the Orbitrap mass analyzer (up to 140,000 Th/Th) and capability in dealing with massive spectral data sets by positive matrix factorization, we were able to identify the major gas-phase oxidation processes leading to the formation of oxygenated organic molecules (OOM) in Shanghai. Nine main factors from three independent sub-range analysis were identified. More than 90% of OOM are of anthropogenic origin and >60% are nitrogen-containing molecules, mainly dominated by the RO2 + NO and/or NO3 chemistry. The emission control during the EXPO showed that even though the restriction was effectual in significantly lowering the primary pollutants (20-70% decrease), the secondary oxidation products responded less effectively (14% decrease), or even increased (50 to >200%) due to the enhancement of ozone and the lowered condensation sink, indicating the importance of a stricter multi-pollutant coordinated strategy in primary and secondary pollution mitigation.

Limited Resection Versus Pancreaticoduodenectomy for Duodenal Gastrointestinal Stromal Tumors? Enucleation Interferes in the Debate: A European Multicenter Retrospective Cohort Study.

BACKGROUND: The optimal surgical procedure for duodenal gastrointestinal stromal tumors (D-GISTs) remains poorly defined. Pancreaticoduodenectomy (PD) allows for a wide resection but is associated with a high morbidity rate. OBJECTIVES: The aim of this study was to compare the short- and long-term outcomes of PD versus limited resection (LR) for D-GISTs and to evaluate the role of tumor enucleation (EN). METHODS: In this retrospective European multicenter cohort study, 100 patients who underwent resection for D-GIST between 2001 and 2013 were compared between PD (n = 19) and LR (n = 81). LR included segmental duodenectomy (n = 47), wedge resection (n = 21), or EN (n = 13). The primary objective was to evaluate disease-free survival (DFS) between the groups, while the secondary objectives were to analyze the overall morbidity and mortality, radicality of resection, and 5-year overall survival (OS) and recurrence rates between groups. Furthermore, the short- and long-term outcomes of EN were evaluated. RESULTS: Baseline characteristics were comparable between the PD and LR groups, except for a more frequent D2 tumor location in the PD group (68.3% vs. 29.6%; p = 0.016). Postoperative morbidity was higher after PD (68.4% vs. 23.5%; p < 0.001). OS (p = 0.70) and DFS (p = 0.64) were comparable after adjustment for D2 location and adjuvant therapy rate. EN was performed more in American Society of Anesthesiologists (ASA) stage III/IV patients with tumors < 5 cm and was associated with a 5-year OS rate of 84.6%, without any disease recurrences. CONCLUSIONS: For D-GISTs, LR should be the procedure of choice due to lower morbidity and similar oncological outcomes compared with PD. In selected patients, EN appears to be associated with equivalent short- and long-term outcomes. Based on these results, a surgical treatment algorithm is proposed.

Temporally regulated cell migration is sensitive to variation in body size.

Few studies have measured the robustness to perturbations of the final position of a long-range migrating cell. In the nematode Caenorhabditis elegans, the QR neuroblast migrates anteriorly, while undergoing three division rounds. We study the final position of two of its great-granddaughters, the end of migration of which was previously shown to depend on a timing mechanism. We find that the variance in their final position is similar to that of other long-range migrating neurons. As expected from the timing mechanism, the position of QR descendants depends on body size, which we varied by changing maternal age or using body size mutants. Using a mathematical model, we show that body size variation is partially compensated for. Applying environmental perturbations, we find that the variance in final position increased following starvation at hatching. The mean position is displaced upon a temperature shift. Finally, highly significant variation was found among C. elegans wild isolates. Overall, this study reveals that the final position of these neurons is quite robust to stochastic variation, shows some sensitivity to body size and to external perturbations, and varies in the species.This article has an associated 'The people behind the papers' interview.

A broad mutational target explains a fast rate of phenotypic evolution.

The rapid evolution of a trait in a clade of organisms can be explained by the sustained action of natural selection or by a high mutational variance, that is the propensity to change under spontaneous mutation. The causes for a high mutational variance are still elusive. In some cases, fast evolution depends on the high mutation rate of one or few loci with short tandem repeats. Here, we report on the fastest evolving cell fate among vulva precursor cells in Caenorhabditis nematodes, that of P3.p. We identify and validate causal mutations underlying P3.p's high mutational variance. We find that these positions do not present any characteristics of a high mutation rate, are scattered across the genome and the corresponding genes belong to distinct biological pathways. Our data indicate that a broad mutational target size is the cause of the high mutational variance and of the corresponding fast phenotypic evolutionary rate.

Heritable characteristics or traits of a group of organisms, for example the large brain size of primates or the hooves of a horse, are determined by genes, the environment, and by the interactions between them. Traits can change over time and generations when enough mutations in these genes have spread in a species to result in visible differences. However, some traits, such as the large brain of primates, evolve faster than others, but why this is the case has been unclear. It could be that a few specific genes important for that trait in question mutate at a high rate, or, that many genes affect the trait, creating a lot of variation for natural selection to choose from. Here, Besnard, Picao-Osorio et al. studied the roundworm Caenorhabditis elegans to better understand the causes underlying the different rates of trait evolution. These worms have a short life cycle and evolve quickly over many generations, making them an ideal candidate for studying mutation rates in different traits. Previous studies have shown that one of C. elegans' six cells of the reproductive system evolves faster than the others. To investigate this further, Besnard, Picao-Osorio et al. analysed the genetic mutations driving change in this cell in 250 worm generations. The results showed that five mutations in five different genes ­ all responsible for different processes in the cells ­ were behind the supercharged evolution of this particular cell. This suggests that fast evolution results from natural selection acting upon a collection of genes, rather than one gene, and that many genes and pathways shape this trait. In conclusion, these results demonstrate that how traits are coded at the molecular level, in one gene or many, can influence the rate at which they evolve.