A Weight of Evidence approach to support the assessment of the quality of Manila clam farming sites in a coastal lagoon

Aquaculture productivity in coastal lagoons is endangered by a complex interplay of anthropogenic and environmental factors, amplified by the effects of climate change in these sensitive areas. To reach a more comprehensive assessment of farming sites quality, a quantitative Weight of Evidence approach (QWoE) is applied for the first time to data collected at four Manila clam (R. philippinarum) farming sites in the Venice lagoon (Italy). This included sediment quality, chemical bioaccumulation, and biological responses. Results revealed a greater hazard for sites closer to the open sea. In these areas, the combination of sediment characteristics and a higher frequency of salinity and temperature stress could explain the alterations measured at a transcriptional and biomarker level. The findings demonstrate that a QWoE approach that integrates multiple sources of evidence should also include physicochemical conditions in order to better understand the impacts of human activities and other stressors on clam aquaculture productivity.

Long term follow-up of a multicentre cohort of COVID-19 patients with pulmonary embolism: Anticoagulation management and outcomes

BACKGROUND AND AIMS

Pulmonary embolism (PE) is a frequent complication in COVID19 hospitalized patients. Inflammatory storm and endothelial dysfunction due to the virus seem to be the two major risk factors for PE. Consequently, PE related to COVID19 could be consider as triggered by a transient inflammatory acute phase and treated for no longer than 3 months. However, few data are available on management of anticoagulation and risk of venous thromboembolic (VTE) recurrences in these patients and guidelines are still undefined. Aim of the present study is to evaluate the long-term follow-up of a cohort of covid-19 patients with PE.

METHODS

We conducted a retrospective multicenter study in four Italian hospitals between March 1st, 2020, and May 31st, 2021 in patients who experienced a PE during hospitalization for a COVID-19 pneumonia, excluding patients who died during hospitalization. Baseline characteristics were collected and patients were grouped according to duration of anticoagulant treatment (< 3 months or > 3 months). The primary outcome was incidence of VTE recurrence while secondary outcome was the composite of deaths, major hemorrhages and VTE recurrence during follow-up.

RESULTS

106 patients with PE were discharged, of these 95 (89.6 %) had follow up longer than 3 months (seven patients were lost to follow up and four died within three months). The median follow-up was 13 months (IQR 1-19). Overall, 23 % of subjects (22/95) were treated for 3 months or less and 76.8 % (73/95) received anticoagulation for >3 months. Of patients in the short treatment group, 4.5 % died, compared with 5.5 % of those in the longer treatment group (p = NS); no difference was shown in risk of VTE recurrence (0 % vs 4.1 %, p = NS), major bleeding (4.5 % vs 4.1 %, p = NS) or in composite outcome (9.1 % vs 11 %, p = NS). No difference was found between the two treatment groups for composite outcome using the Kaplan-Meier analysis (Log Rank Test p = 0.387).

CONCLUSION

In our retrospective multi-center cohort, prolongation of duration of anticoagulation seems not to affect risk of VTE recurrences, deaths and bleeding after a PE related to COVID-19.

Selective advantage of epigenetically disrupted cancer cells via phenotypic inertia

The evolution of established cancers is driven by selection of cells with enhanced fitness. Subclonal mutations in numerous epigenetic regulator genes are common across cancer types, yet their functional impact has been unclear. Here, we show that disruption of the epigenetic regulatory network increases the tolerance of cancer cells to unfavorable environments experienced within growing tumors by promoting the emergence of stress-resistant subpopulations. Disruption of epigenetic control does not promote selection of genetically defined subclones or favor a phenotypic switch in response to environmental changes. Instead, it prevents cells from mounting an efficient stress response via modulation of global transcriptional activity. This "transcriptional numbness" lowers the probability of cell death at early stages, increasing the chance of long-term adaptation at the population level. Our findings provide a mechanistic explanation for the widespread selection of subclonal epigenetic-related mutations in cancer and uncover phenotypic inertia as a cellular trait that drives subclone expansion.

Interferon regulatory factor 1 (IRF1) controls the metabolic programmes of low-grade pancreatic cancer cells

OBJECTIVE

Pancreatic ductal adenocarcinomas (PDACs) include heterogeneous mixtures of low-grade cells forming pseudoglandular structures and compact nests of high-grade cells organised in non-glandular patterns. We previously reported that low-grade PDAC cells display high expression of interferon regulatory factor 1 (IRF1), a pivotal transcription factor of the interferon (IFN) system, suggesting grade-specific, cell-intrinsic activation of IFN responses. Here, we set out to determine the molecular bases and the functional impact of the activation of IFN-regulated responses in human PDACs.

DESIGN

We first confirmed the correlation between glandular differentiation and molecular subtypes of PDAC on the one hand, and the expression of IRF1 and IFN-stimulated genes on the other. We next used unbiased omics approaches to systematically analyse basal and IFN-regulated responses in low-grade and high-grade PDAC cells, as well as the impact of IRF1 on gene expression programmes and metabolic profiles of PDAC cells.

RESULTS

High-level expression of IRF1 in low-grade PDAC cells was controlled by endodermal lineage-determining transcription factors. IRF1-regulated gene expression equipped low-grade PDAC cells with distinctive properties related to antigen presentation and processing as well as responsiveness to IFN stimulation. Notably, IRF1 also controlled the characteristic metabolic profile of low-grade PDAC cells, suppressing both mitochondrial respiration and fatty acid synthesis, which may in part explain its growth-inhibiting activity.

CONCLUSION

IRF1 links endodermal differentiation to the expression of genes controlling antigen presentation and processing as well as to the specification of the metabolic profile characteristic of classical PDAC cells.

Effects of environmental concentrations of the fragrance amyl salicylate on the mediterranean mussel Mytilus galloprovincialis

Amyl salicylate (AS) is a fragrance massively used as a personal care product and following the discharged in wastewaters may end up in the aquatic environment representing a potential threat for the ecosystem and living organisms. AS was recently detected in water of the Venice Lagoon, a vulnerable area continuously subjected to the income of anthropogenic chemicals. The lagoon is a relevant area for mollusc farming, including the Mediterranean mussels (Mytilus galloprovincialis) having an important economic and ecological role. Despite high levels of AS occurred in water of the Lagoon of Venice, no studies investigated the possible consequences of AS exposures on species inhabiting this ecosystem to date. For the first time, we applied a multidisciplinary approach to investigate the potential effects of the fragrance AS on Mediterranean mussels. To reach such a goal, bioaccumulation, cellular, biochemical, and molecular analyses (RNA-seq and microbiota characterization) were measured in mussels treated for 7 and 14 days with different AS Venice lagoon environmental levels (0.1 and 0.5 μg L^-1). Despite chemical investigations suggested low AS bioaccumulation capability, cellular and molecular analyses highlighted the disruption of several key cellular processes after the prolonged exposures to the high AS concentration. Among them, potential immunotoxicity and changes in transcriptional regulation of pathways involved in energy metabolism, stress response, apoptosis and cell death regulations have been observed. Conversely, exposure to the low AS concentration demonstrated weak transcriptional changes and transient increased representation of opportunistic pathogens, as Arcobacter genus and Vibrio aestuarianus. Summarizing, this study provides the first overview on the effects of AS on one of the most widely farmed mollusk species.

Tumor cell heterogeneity and its transcriptional bases in pancreatic cancer: a tale of two cell types and their many variants

Pancreatic ductal adenocarcinoma (PDAC), one of the most highly lethal tumors, is characterized by complex histology, with a massive fibrotic stroma in which both pseudo-glandular structures and compact nests of abnormally differentiated tumor cells are embedded, in different proportions and with different mutual relationships in space. This complexity and the heterogeneity of the tumor component have hindered the development of a broadly accepted, clinically actionable classification of PDACs, either on a morphological or a molecular basis. Here, we discuss evidence suggesting that such heterogeneity can to a large extent, albeit not exclusively, be traced back to two main classes of PDAC cells that commonly coexist in the same tumor: cells that maintained their ability to differentiate toward endodermal, mucin-producing epithelia and epithelial cells unable to form glandular structures and instead characterized by various levels of squamous differentiation and the expression of mesenchymal lineage genes. The underlying gene regulatory networks and how they are controlled by distinct transcription factors, as well as the practical implications of these two different populations of tumor cells, are discussed.

Pancreatic Cancer Cells Require the Transcription Factor MYRF to Maintain ER Homeostasis

Many tumors of endodermal origin are composed of highly secretory cancer cells that must adapt endoplasmic reticulum (ER) activity to enable proper folding of secreted proteins and prevent ER stress. We found that pancreatic ductal adenocarcinomas (PDACs) overexpress the myelin regulatory factor (MYRF), an ER membrane-associated transcription factor (TF) released by self-cleavage. MYRF was expressed in the well-differentiated secretory cancer cells, but not in the poorly differentiated quasi-mesenchymal cells that coexist in the same tumor. MYRF expression was controlled by the epithelial identity TF HNF1B, and it acted to fine-tune the expression of genes encoding highly glycosylated, cysteine-rich secretory proteins, thus preventing ER overload. MYRF-deficient PDAC cells showed signs of ER stress, impaired proliferation, and an inability to form spheroids in vitro, while in vivo they generated highly secretory but poorly proliferating and hypocellular tumors. These data indicate a role of MYRF in the control of ER homeostasis in highly secretory PDAC cells.

The effects of glyphosate and AMPA on the mediterranean mussel Mytilus galloprovincialis and its microbiota

Glyphosate, the most widely used herbicide worldwide, targets the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme in the shikimate pathway found in plants and some microorganisms. While the potential for glyphosate to induce a broad range of biological effects in exposed organisms has been demonstrated, the global molecular mechanisms of toxicity and potential effects in bacterial symbionts remain unclear, in particular for ecologically important marine species such as bivalve molluscs. Here, the effects of glyphosate (GLY), its degradation product aminomethylphosphonic acid (AMPA), and a mixture of both (MIX) on the mussel M. galloprovincialis were assessed in a controlled experiment. For the first time, next generation sequencing (RNA-seq and 16S rRNA amplicon sequencing) was used to evaluate such effects at the molecular level in both the host and its respective microbiota. The results suggest that the variable capacity of bacterial species to proliferate in the presence of these compounds and the impairment of host physiological homeostasis due to AMPA and GLY toxicity may cause significant perturbations to the digestive gland microbiota, as well as elicit the spread of potential opportunistic pathogens such as Vibrio spp.. The consequent host-immune system activation identified at the molecular and cellular level could be aimed at controlling changes occurring in the composition of symbiotic microbial communities. Overall, our data raise further concerns about the potential adverse effects of glyphosate and AMPA in marine species, suggesting that both the effects of direct toxicity and the ensuing changes occurring in the host-microbial community must be taken into consideration to determine the overall ecotoxicological hazard of these compounds.

FOXA2 controls the cis-regulatory networks of pancreatic cancer cells in a differentiation grade-specific manner

Differentiation of normal and tumor cells is controlled by regulatory networks enforced by lineage-determining transcription factors (TFs). Among them, TFs such as FOXA1/2 bind naïve chromatin and induce its accessibility, thus establishing new gene regulatory networks. Pancreatic ductal adenocarcinoma (PDAC) is characterized by the coexistence of well- and poorly differentiated cells at all stages of disease. How the transcriptional networks determining such massive cellular heterogeneity are established remains to be determined. We found that FOXA2, a TF controlling pancreas specification, broadly contributed to the cis-regulatory networks of PDACs. Despite being expressed in both well- and poorly differentiated PDAC cells, FOXA2 displayed extensively different genomic distributions and controlled distinct gene expression programs. Grade-specific functions of FOXA2 depended on its partnership with TFs whose expression varied depending on the differentiation grade. These data suggest that FOXA2 contributes to the regulatory networks of heterogeneous PDAC cells via interactions with alternative partner TFs.

Abstract LB-202: Role of the FOXA transcription factors in shaping distinct transcriptional programs in human pancreatic cancers

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest types of cancer and is characterized by a high intra-tumor heterogeneity, with the coexistence of well- and poorly-differentiated cells in virtually all the tumor cases. FOXA1/2 play a fundamental role in pancreas development and are believed to act as pioneer factors, namely to create accessible chromatin by displacing nucleosomes early in development and making genomic regulatory elements available to other transcriptional regulators. Therefore, we asked whether FOXA1/2 also control differentiation in human PDAC. Whereas FOXA1 showed a remarkable propensity to be expressed selectively by well-differentiated tumor areas and cell lines, FOXA2 showed a broad profile of expression throughout PDAC stages. Through the combination of genomic and functional assays we found that FOXA2 contributed to activate distinct transcriptional programs in tumor cells of different grades. Such complexity in FOXA2 activity specifically depended on its interaction with distinct transcription factors selectively expressed in high- or low-grade tumor cells. While in low-grade (well-differentiated) PDAC cells FOXA2 binding specificity relied on the interaction with the epithelial transcription factor HNF1beta, in high-grade cells it depended on the cooperation with HOXB8 and HOXB9. Knocking out these transcription factors was sufficient to abolish differential recruitment of FOXA2 to grade specific genomic sites. In summary, we found that FOXA2 is broadly express throughout PDAC stages and, through the interaction with different transcription factors, shapes the transcriptional program of the different tumor grades in pancreatic cancer. These findings help to shed light on the complexity of PDAC heterogeneity and on the circuitries that maintain PDAC differentiation and grading.

Citation Format: Marta Milan, Gioacchino Natoli. Role of the FOXA transcription factors in shaping distinct transcriptional programs in human pancreatic cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-202.

Ecotoxicological effects of the herbicide glyphosate in non-target aquatic species: Transcriptional responses in the mussel Mytilus galloprovincialis

Glyphosate has been the most widely used herbicide worldwide over the last three decades, raising increasing concerns for its potential impacts on environmental and human health. Recent studies revealed that glyphosate occurs in soil, surface water, and groundwater, and residues are found at all levels of the food chain, such as drinking water, plants, animals, and even in humans. While research has demonstrated that glyphosate can induce a broad range of biological effects in exposed organisms, the global molecular mechanisms of action still need to be elucidated, in particular for marine species. In this study, we characterized for the first time the molecular mechanisms of action of glyphosate in a marine bivalve species after exposure to environmentally realistic concentrations. To reach such a goal, Mediterranean mussels Mytilus galloprovincialis, an ecologically and economically relevant species, were exposed for 21 days to 10, 100, and 1000 μg/L and digestive gland transcriptional profiles were investigated through RNA-seq. Differential expression analysis identified a total of 111, 124, and 211 differentially regulated transcripts at glyphosate concentrations of 10, 100, and 1000 μg/L, respectively. Five genes were found consistently differentially expressed at all investigated concentrations, including SERP2, which plays a role in the protection of unfolded target proteins against degradation, the antiapoptotic protein GIMAP5, and MTMR14, which is involved in macroautophagy. Functional analysis of differentially expressed genes reveals the disruption of several key biological processes, such as energy metabolism and Ca2+ homeostasis, cell signalling, and endoplasmic reticulum stress response. Together, the results obtained suggest that the presence of glyphosate in the marine ecosystem should raise particular concern because of its significant effects even at the lowest concentration.

Long-term exposure of Mytilus galloprovincialis to diclofenac, Ibuprofen and Ketoprofen: Insights into bioavailability, biomarkers and transcriptomic changes

Non-steroidal anti-inflammatory drugs (NSAIDs) represent a growing concern for marine ecosystems due to their ubiquitous occurrence and documented adverse effects on non-target organisms. Despite the remarkable efforts to elucidate bioaccumulation and ecotoxicological potential under short-term conditions, limited and fragmentary information is available for chronic exposures. In this study bioavailability, molecular and cellular effects of diclofenac (DIC), ibuprofen (IBU) and ketoprofen (KET) were investigated in mussels Mytilus galloprovincialis exposed to the realistic environmental concentration of 2.5 μg/L for up to 60 days. Results indicated a significant accumulation of DIC and IBU but without a clear time-dependent trend; on the other hand, KET concentrations were always below the detection limit. Analyses of a large panel of molecular, biochemical and cellular biomarkers highlighted that all investigated NSAIDs caused alterations of immunological parameters, genotoxic effects, modulation of lipid metabolism and changes in cellular turn-over. This study provided the evidence of long-term ecotoxicological potential of NSAIDs, further unraveling the possible hazard for wild marine organisms.

Comparison of Four Different Short Dialysis Techniques

The goal of shortening dialysis treatment time has stimulated the development of new, highly efficient dialytic strategies. In this study the Authors compared four different short dialysis treatments in terms of efficiency, clinical tolerance, technological investment and costs: 1) Rapid bicarbonate dialysis with 1.5 sq.m. cuprophane membrane; 2) High flux biofiltration with 1.2 sq.m. AN69S hollow fiber membrane; 3) Hemodiafiltration with 1.2-1.9. sq.m. polysulphonic hollow fiber hemodiafilters, and 4) High flux hemodiafiltration with two serial hemodiafilters with AN69s membrane (total 2.4 sq.m.).

Hydraulic properties and solute clearances at different blood flows (300-500 ml/min) were tested for each technique. Once the optimal operative level was established three patients were treated with each technique for at least six months. Since BUN clearance averaged 310 ml/min, the treatment duration varied from 120 to 180 min/session with KT/V always higher than 1. The average protein catabolic rate was 0.9 g/kg/24h. Clinical tolerance was generally good, slightly better in treatments with a high convective component. Despite the greater efficiency of treatment No. 4, the technological requirements and costs are such that the others are currently more feasible and acceptable in clinical routine.

The study demonstrates that reduction of dialysis treatment time is possible in all centres in a selected population with adequate blood access. Treatment No. 1 can even be performed with standard equipment and cuprophan membranes, while bicarbonate in the dialysate is mandatory. The real limit to shortening treatment time seems to be related to the maximal rate of ultrafiltration achievable in the patient during dialysis.

Technical and clinical evaluation of a new polyamide hollow fiber hemofilter for CAVH

We carried out an in-vivo and in-vitro evaluation of a new polyamide hollow fiber hemofilter especially designed to operate under conditions of low pressure and low blood flow, such as in continuous arteriovenous hemofiltration (CAVH).

The results obtained suggest that this filter is a prototype of a new generation of hemofilters especially designed for CAVH. Its low resistance permits its use even in patients with severe hypotension. The high blood flows achieved at a given pressure reduce the risk of clotting and increase the ultrafiltration rate. When an average ultrafiltration of 20-25 ml/min is achieved in 24 hours CAVH becomes very efficient, and alternative techniques to increase its efficiency are no longer required.

Solute and Water Transport during Continuous Arteriovenous Hemofiltration (CAVH)

The transport mechanisms governing solvent and solute removal during CAVH were elucidated on the basis of in vitro and in vivo observations.

Using a typical hemofilter (Diafilter D-20, AMICON), filtration rate rose with inlet blood flow rate until an asymptote was reached at blood flows of approximately 150 ml/min. The onset of the asymptote coincided with transition from a regime controlled by oncotic pressure (filtration pressure equilibrium), to one governed by simple Darcy's law filtration behaviour. Subsequent measurements showed that under clinical conditions, CAVH is generally in the pre-asymptotic regime and operates at filtration pressure equilibrium.

These observations offer the theoretical bases for a new design for CAVH hemofilters.

As a possible corollary, middle-molecule sieving coefficients were found to be stable with time during CAVH in vivo, whereas in chronic mechanical hemofiltration they declined significantly during clinical treatment. The sieving coefficients, however, were lower in mechanical hemofiltration from the beginning of the session.

These observations suggest that the measured sieving coefficient for a membrane is not necessarily a constant directly and solely related to the membrane standard reflection coefficient for a given solute. Concentration polarization and the ultrafiltration rate per unit of surface area may in fact have a major effect on the final concentration of solutes in the ultrafiltrate.

In Vitro and in Vivo Evaluation of a New Polysulfone Membrane for Hemodialysis. Reference Methodology and Clinical Results: (Part 1: In Vitro Study)

Different high flux membranes have been recently developed. The present study is aimed at describing the technical features and the clinical performances of a new high flux polysulfone membrane (T-sulfone, Toray Japan). The study has been carried out on two different dialyzers (surface area = 1.3 and 1.8 m2). The filters have been tested in vitro under definite experimental conditions. The hydraulic flow resistance, the pressure drop in the blood compartment and the hydraulic permeability have been determined in a wide range of in vitro experimental conditions. The in vitro sieving coefficients for various solutes have also been determined utilizing human blood. Hydraulic permeability was found in the range of 28.4 ml/h/mmHg/m2 and sieving coefficients were between 0.96 and 1.0 for all low molecular weight solutes. The sieving coefficient for inulin was 0.95. The pressure drop in the filter at 300 ml/min of blood flow was 95 mmHg for the 1.3 m2 and 57 mmHg for the 1.8 m2. The filters are then designed to operate in the presence of high blood flows without excessive resistance in the blood compartment. The blood compartment analyzed by means of a special radiological sequence obtained with a helical scanner after dye injection confirmed the homogeneous distribution of the blood flow in several cross sections of the bundle. Adequate distribution of dialysate was confirmed with a similar method applied to the dialysate compartment. The new imaging techniques utilized were greatly helpful to determine adequacy of filter design and flows distribution.

Double Pass Dialysis: A New Method of Renal Replacement in Patients with Malfunctioning Vascular Access

Several patients undergoing chronic renal replacement therapy present problems related to their vascular access. Low blood flows and high rates of recirculation are common in such patients in which, for this reason, it becomes difficult to apply highly efficient techniques or techniques where diffusion and convection are combined as in hemodiafiltration. In these patients we studied the possibility of partially recirculating the blood in the extracorporeal circuit in order to increase the flow rate per single hollow fiber; we defined our system “double pass dialysis”. We evaluated the system's efficiency in 12 patients during 24 dialysis sessions: 12 high flux dialysis sessions (without reinfusion) and 12 hemodiafiltration sessions (9 liters reinfusion). Different surfaces of polyacrylonitrile dialyzers were utilized (1.3-1.7-2.1 sqm) at 250 and 350 ml/min of blood flow with or without 100 ml/min of recirculation. During each dialysis session blood and dialysate samples were taken in order to calculate BUN, Creatinine, Phosphate and Inuline clearances from both the blood and dialysate side. The clearances of low molecular weight solutes were not really influenced by the artificial increase of the blood flow, but on the other hand, the clearances of higher molecular weight solutes increased from 10 to 30% during both high flux dialysis and hemodiafiltration with recirculation. This increase was evident mostly in hemodiafiltration suggesting that the cleaning effect on the membrane has a positive impact on the permeability. The good clinical results obtained with the double pass dialysis show that the system is safe and reliable and may become a valid support in critical situations in order to reach adequate dialysis treatment.

On line filtration of dialysate: structural and functional features of an asymmetric polysulfone hollow fiber ultrafilter (Diaclean®)

The endotoxin transfer across dialysis membranes has been investigated using specific in vitro circuits. Backdiffusion and backfiltration have been analyzed and most dialysis membranes have shown to be permeable to LAL positive substances. Synthetic membranes however display the better capacity of retention of these products despite their higher porosity and permeability. For such reason synthetic polysulfone ultrafilters are used as pyrogen filters to obtain ultrapure dialysate. We have investigated the characteristics of a polysulfone ultrafilter named Diaclean and manufactured by Amicon Ireland. The capacity of endotoxin retention has been investigated both in filtration and backfiltration modes on new and used ultrafilters. The capacity of endotoxin adsorption was investigated as well. Used ultrafilters appeared to maintain the retention capacity and the adsorption capacity up to 4 months of use. Only slight differences were noted from the baseline values (p = n.s.). The best adsorption capacity is always displayed by the outer layer of the membrane suggesting its best utilization in back filtration mode with tangential flow. No morphological changes were observed in the used membrane analyzed by scanning electron microscopy.