Search

Listeria monocytogenes is a saprophytic gram-positive bacterium, and an opportunistic foodborne pathogen that can produce listeriosis in humans and animals. It has evolved an exceptional ability to adapt to stress conditions encountered in different environments, resulting in a ubiquitous distribution. Because some food preservation methods and disinfection protocols in food-processing environments cannot efficiently prevent contaminations, L. monocytogenes constitutes a threat to human health and a challenge to food safety. In the host, Listeria colonizes the gastrointestinal tract, crosses the intestinal barrier, and disseminates through the blood to target organs. In immunocompromised individuals, the elderly, and pregnant women, the pathogen can cross the blood-brain and placental barriers, leading to neurolisteriosis and materno-fetal listeriosis. Molecular and cell biology studies of infection have proven L. monocytogenes to be a versatile pathogen that deploys unique strategies to invade different cell types, survive and move inside the eukaryotic host cell, and spread from cell to cell. Here, we present the multifaceted Listeria life cycle from a comprehensive perspective. We discuss genetic features of pathogenic Listeria species, analyze factors involved in food contamination, and review bacterial strategies to tolerate stresses encountered both during food processing and along the host’s gastrointestinal tract. Then we dissect host–pathogen interactions underlying listerial pathogenesis in mammals from a cell biology and systemic point of view. Finally, we summarize the epidemiology, pathophysiology, and clinical features of listeriosis in humans and animals. This work aims to gather information from different fields crucial for a comprehensive understanding of the pathogenesis of L. monocytogenes., Graphical abstract

Rosette morphology across Arabidopsis accessions exhibits considerable variation. Here we report a high-throughput phenotyping approach based on automatic image analysis to quantify rosette shape and dissect the underlying genetic architecture. Shape measurements of the rosettes in a core set of Recombinant Inbred Lines from an advanced mapping population (Multiparent Advanced Generation Inter-Cross or MAGIC) derived from inter-crossing 19 natural accessions. Image acquisition and analysis was scaled to extract geometric descriptors from time stamped images of growing rosettes. Shape analyses revealed heritable morphological variation at early juvenile stages and QTL mapping resulted in over 116 chromosomal regions associated with trait variation within the population. Many QTL linked to variation in shape were located near genes related to hormonal signalling and signal transduction pathways while others are involved in shade avoidance and transition to flowering. Our results suggest rosette shape arises from modular integration of sub-organ morphologies and can be considered a functional trait subjected to selective pressures of subsequent morphological traits. On an applied aspect, QTLs found will be candidates for further research on plant architecture.

670 Background: Pancreatic Ductal Adenocarcinoma (PDAC) has historically been an important diagnostic and therapeutic challenge. The multidisciplinary approach and new diagnostic techniques’ implementation have modified this process. Methods: We conducted a retrospective analysis based on clinical data of patients with PDAC between the years 2010 to 2021, analyzing the diagnosis and initial treatment evolution. Results: 673 patients between 2010-2021 with a suspected diagnosis of pancreatic adenocarcinoma were reviewed. Most of them were metastatic (n=362; 53.8%), followed by locally advanced unresectable (n=166; 24.7%) and resectable or borderline resectable (n=145; 21.5%). Regarding the pathological diagnosis, it was not possible in 62 patients (9.2%), varying over time from 21.2% in 2010-2012 to 1% in 2019-2021 (p

740 Background: Several inflammatory scores such as the Systemic Inflammation Response Index (SIRI), the Inflammation Index Score (IIS), and the Neutrophil Lymphocyte Ratio (NLR) have been reported to have prognostic value in PDAC with different results. We hypothesize that the KS, designed to predict the risk of cancer-associated thrombosis, may also be a surrogate marker for inflammation to be included as a relevant prognostic index for PDAC. Methods: Baseline characteristics and individual SIRI, IIS, NLR and KS indexes from 197 PDAC patients diagnosed in our center between 2019 and 2021 have been retrospectively recorded. PFS and OS (Log-rank test) have been used to compare the different scores of each index in the whole population as well as in the metastatic setting. Kruskal-Wallis test and Mann-Whitney test were also done to determine if the SIRI varies significantly between KRS values. Results: Of the 197 patients analyzed, 41 were resectable (20.8%), 54 locally advanced (27.4%) and 102 metastatic (51.8%). Patients with intermediate risk according to KS (2 points, n = 131, 66.5%) had a significantly higher median PFS (8.4 vs. 4.8 months, p = 0.03) and significantly higher OS (12.9 vs. 7.7 months, p = 0.002) than those with high-risk (> 3 points, n = 66, 33.5%). The median OS for patients with low (< 3,000) and high (> 3,000) SIRI was 13.1 and 9.3 months respectively (p = 0.05). No significant differences were observed in PFS. In the metastatic setting, a low SIRI was significantly associated with higher OS (10.6 vs. 5.8, p = 0.016). No significant differences were observed in patients with low vs. high IIS and NLR. The Kruskal-Wallis test indicates that SIRI values vary between at least two KS values (p < 0.001). The Mann-Whitney test found significant differences between the SIRI values from S 2 and 3 (p = 0.002) as well as 2 and 4 (p = 0.04). SIRI values were higher in patients with KRS > 3 vs. 2. Conclusions: This retrospective analysis showed that patients with lower KS live longer and progress later than those with higher KS. Lower SIRI is associated with better survival in metastatic patients, being on the verge of statistical significance in the whole cohort. There is a strong correlation between SIRI and KS. In this cohort of unselected PDAC patients, KS is a prognostic factor for OS and PFS that correlates with subclinical inflammation and demonstrates to be a better predictor than other inflammatory indexes that deserves further analysis.

Listeria monocytogenes is a saprophytic gram-positive bacterium, and an opportunistic foodborne pathogen that can produce listeriosis in humans and animals. It has evolved an exceptional ability to adapt to stress conditions encountered in different environments, resulting in a ubiquitous distribution. Because some food preservation methods and disinfection protocols in food-processing environments cannot efficiently prevent contaminations, L. monocytogenes constitutes a threat to human health and a challenge to food safety. In the host, Listeria colonizes the gastrointestinal tract, crosses the intestinal barrier, and disseminates through the blood to target organs. In immunocompromised individuals, the elderly, and pregnant women, the pathogen can cross the blood-brain and placental barriers, leading to neurolisteriosis and materno-fetal listeriosis. Molecular and cell biology studies of infection have proven L. monocytogenes to be a versatile pathogen that deploys unique strategies to invade different cell types, survive and move inside the eukaryotic host cell, and spread from cell to cell. Here, we present the multifaceted Listeria life cycle from a comprehensive perspective. We discuss genetic features of pathogenic Listeria species, analyze factors involved in food contamination, and review bacterial strategies to tolerate stresses encountered both during food processing and along the host’s gastrointestinal tract. Then we dissect host–pathogen interactions underlying listerial pathogenesis in mammals from a cell biology and systemic point of view. Finally, we summarize the epidemiology, pathophysiology, and clinical features of listeriosis in humans and animals. This work aims to gather information from different fields crucial for a comprehensive understanding of the pathogenesis of L. monocytogenes. Spanish Ministry of Science and Innovation (PGC2018-096364-B-I00). JJQ was supported by the Generalitat Valenciana (GV/2018/A/183) and the Spanish Ministry of Science and Innovation (PID2019-110764RA-I00 /AEI/10.13039/501100011033). FG-dP was supported by the European Union’s Horizon 2020 Research-and-Innovation Program under Marie Sklodowska-Curie grant agreement no. 721456. JJQ was a recipient of the “Ramón y Cajal” Programme from the Spanish Ministry of Science, Innovation, and Universities (RYC-2018-024985-I). AM-G was funded by the Youth Employment Initiative from the Comunidad de Madrid. CP-G was funded by the Universidad Cardenal Herrera-CEU

Background: Liver abscesses are uncommon, but they are associated with a hospital mortality rate of 10% in patients without cancer. However, its relevance in cancer patients in terms of survival and length of hospitalization is unknown. Patients and Methods: We conducted an observational study in order to analyze the impact of liver abscesses in hospitalized cancer patients. Eligible patients were adults with a solid tumor, received antineoplastic treatment and were hospitalized in our department with a diagnosis of liver abscesses. Primary end-points of the study were overall survival (OS) and mean hospital stay (MHS). Secondary end-points were the description of risk factors of liver abscesses, isolated microorganisms and the specific treatment. Results: In our study the incidence of liver abscesses in cancer patients was 1.18%. Median age was 63 years, 60% were men, and the vast majority of patients had an advanced bilio-pancreatic tumor (85%). With a median follow-up of 18 months, median OS was 6 months (95% CI: 1-11); and OS probability at 18-month was 19%. MHS was 27.2 days (95% CI: 20.3-40.7). Risk factors for developing liver abscesses were: a) bilio-pancreatic cancers; b) chemotherapy administration; c) severe malnutrition; and d) biliary drainage/prosthesis. Ten patients (50%) had bacteremia, and the most common isolated microorganism was E.coli (30%). Percutaneous drainage of abscesses was performed in 40% of the patients, and all patients were treated with broad-spectrum antibiotics. Conclusions: Although liver abscesses were uncommon, they were associated with a prolonged hospitalization and poor outcome in cancer patients.