Comparison of arterial hypotension incidence during general anesthesia induction - target-controlled infusion vs. bolus injection of propofol: a randomized clinical trial.

BACKGROUND: The incidence of arterial hypotension during induction of general anesthesia is influenced by the method of propofol administration, but there is a dearth of randomized clinical trials comparing bolus injection and target-controlled infusion in relation to arterial hypotension. This study seeks to compare the incidence of arterial hypotension between these two methods of propofol administration. METHODS: This prospective, randomized, single-center, non-blinded study included 60 patients (aged 35 to 55 years), classified as ASA physical status I or II, who were undergoing non-cardiac surgeries. They were randomly allocated using a computer to two groups based on the method of propofol administration during the induction of general anesthesia: the Target Group, receiving target-controlled infusion at 4 µg.mL-1, and the Bolus Group, receiving a bolus infusion of 2 mg.kg-1. Both groups also received midazolam 2 mg, fentanyl 3 µg.kg-1, and rocuronium 0.6 mg.kg-1. Over the first 10 minutes of anesthesia induction, Mean Arterial Pressure (MAP), Heart Rate (HR), level of Consciousness (qCON), and Suppression Rate (SR) were recorded every 2 minutes. RESULTS: Twenty-seven patients remained in the TCI group, while 28 were in the Bolus group. Repeated measure analysis using mixed-effects models could not reject the null hypothesis for the effect of group-time interactions in MAP (p = 0.85), HR (p = 0.49), SR (p = 0.44), or qCON (p = 0.72). The difference in means for qCON (60.2 for TCI, 50.5 for bolus, p < 0.001), MAP (90.3 for TCI, 86.2 for bolus, p < 0.006), HR (76.2 for TCI, 76.9 for bolus, p = 0.93), and SR (0.01 for TCI, 5.5 for bolus, p < 0.001), irrespective of time (whole period means), revealed some significant differences. CONCLUSION: Patients who received propofol bolus injection exhibited a lower mean arterial pressure, a greater variation in the level of consciousness, and a higher suppression rate compared to those who received it as a target-controlled infusion. However, the interaction effect between groups and time remains inconclusive.

SNX27: A trans-species cognitive modulator with implications for anxiety and stress susceptibility.

Sorting Nexin 27 (SNX27) is a brain-enriched endosome-associated cargo adaptor that shapes excitatory control, being relevant for cognitive and reward processing, and for several neurological conditions. Despite this, SNX27's role in the nervous system remains poorly explored. To further understand SNX27 function, we performed an extensive behavioral characterization comprising motor, cognitive and emotional dimensions of SNX27+/- mice. Furthermore, attending on the recently described association between SNX27 function and cellular stress signaling mechanisms in vitro, we explored SNX27-stress interplay using a Caenorhabditis elegans Δsnx-27 mutant and wild-type (WT) rodents after stress exposure. SNX27+/- mice, as C. elegans Δsnx-27 mutants, present cognitive impairments, highlighting a conserved role for SNX27 in cognitive modulation across species. Interestingly, SNX27 downmodulation leads to anxiety-like behavior in mice evaluated in the Elevated Plus Maze (EPM). This anxious phenotype is associated with increased dendritic complexity of the bed nucleus of the stria terminalis (BNST) neurons, and increased complexity of the basolateral amygdala (BLA) pyramidal neurons. These findings highlight the still unknown role of SNX27 in anxiety regulation. Moreover, we uncovered a direct link between SNX27 dysfunction and stress susceptibility in C. elegans and found that stress-exposed rodents display decreased SNX27 levels in stress-susceptible brain regions. Altogether, we provided new insights on SNX27's relevance in anxiety-related behaviors and neuronal structure in stress-associated brain regions.

MicroRNA-124-3p Modulates Alpha-Synuclein Expression Levels in a Paraquat-Induced in vivo Model for Parkinson's Disease.

Parkinson's disease (PD) is the second most prevalent neurodegenerative disease and the most common movement disorder. Although PD etiology is not fully understood, alpha (α)-synuclein is a key protein involved in PD pathology. MicroRNAs (miRNA), small gene regulatory RNAs that control gene expression, have been identified as biomarkers and potential therapeutic targets for brain diseases, including PD. In particular, miR-124 is downregulated in the plasma and brain samples of PD patients. Recently we showed that the brain delivery of miR-124 counteracts 6-hydroxydopamine-induced motor deficits. However, its role in α-synuclein pathology has never been addressed. Here we used paraquat (PQ)-induced rat PD model to evaluate the role of miR-124-3p in α-synuclein accumulation and dopaminergic neuroprotection. Our results showed that an intranigral administration of miR-124-3p reduced the expression and aggregation of α-synuclein in the substantia nigra (SN) of rats exposed to PQ. NADPH oxidases (NOX), responsible for reactive oxygen species generation, have been considered major players in the development of α-synuclein pathology. Accordingly, miR-124-3p decreased protein expression levels of NOX1 and its activator, small GTPase Rac1, in the SN of PQ-lesioned rats. Moreover, miR-124-3p was able to counteract the reduced levels of pituitary homeobox 3 (PITX3), a protein required for the dopaminergic phenotype, induced by PQ in the SN. This is the first study showing that miR-124-3p decreases PQ-induced α-synuclein levels and the associated NOX1/Rac1 signaling pathway, and impacts PITX3 protein levels, supporting the potential of miR-124-3p as a disease-modifying agent for PD and related α-synucleinopathies.

Remodulation of bacterial transcriptome after acquisition of foreign DNA: the case of irp-HPI high-pathogenicity island in Vibrio anguillarum.

The high-pathogenicity island irp-HPI is widespread in Vibrionaceae and encodes the siderophore piscibactin, as well as the regulator PbtA that is essential for its expression. In this work, we aim to study whether PbtA directly interacts with irp-HPI promoters. Furthermore, we hypothesize that PbtA, and thereby the acquisition of irp-HPI island, may also influence the expression of other genes elsewhere in the bacterial genome. To address this question, an RNAseq analysis was conducted to identify differentially expressed genes after pbtA deletion in Vibrio anguillarum RV22 genetic background. The results showed that PbtA not only modulates the irp-HPI genes but also modulates the expression of a plethora of V. anguillarum core genome genes, inducing nitrate, arginine, and sulfate metabolism, T6SS1, and quorum sensing, while repressing lipopolysaccharide (LPS) production, MARTX toxin, and major porins such as OmpV and ChiP. The direct binding of the C-terminal domain of PbtA to piscibactin promoters (PfrpA and PfrpC), quorum sensing (vanT), LPS transporter wza, and T6SS structure- and effector-encoding genes was demonstrated by electrophoretic mobility shift assay (EMSA). The results provide valuable insights into the regulatory mechanisms underlying the expression of irp-HPI island and its impact on Vibrios transcriptome, with implications in pathogenesis.IMPORTANCEHorizontal gene transfer enables bacteria to acquire traits, such as virulence factors, thereby increasing the risk of the emergence of new pathogens. irp-HPI genomic island has a broad dissemination in Vibrionaceae and is present in numerous potentially pathogenic marine bacteria, some of which can infect humans. Previous works showed that certain V. anguillarum strains exhibit an expanded host range plasticity and heightened virulence, a phenomenon linked to the acquisition of the irp-HPI genomic island. The present work shows that this adaptive capability is likely achieved through comprehensive changes in the transcriptome of the bacteria and that these changes are mediated by the master regulator PbtA encoded within the irp-HPI element. Our results shed light on the broad implications of horizontal gene transfer in bacterial evolution, showing that the acquired DNA can directly mediate changes in the expression of the core genome, with profounds implications in pathogenesis.

Unconventional structure and mechanisms for membrane interaction and translocation of the NF-κB-targeting toxin AIP56.

Bacterial AB toxins are secreted key virulence factors that are internalized by target cells through receptor-mediated endocytosis, translocating their enzymatic domain to the cytosol from endosomes (short-trip) or the endoplasmic reticulum (long-trip). To accomplish this, bacterial AB toxins evolved a multidomain structure organized into either a single polypeptide chain or non-covalently associated polypeptide chains. The prototypical short-trip single-chain toxin is characterized by a receptor-binding domain that confers cellular specificity and a translocation domain responsible for pore formation whereby the catalytic domain translocates to the cytosol in an endosomal acidification-dependent way. In this work, the determination of the three-dimensional structure of AIP56 shows that, instead of a two-domain organization suggested by previous studies, AIP56 has three-domains: a non-LEE encoded effector C (NleC)-like catalytic domain associated with a small middle domain that contains the linker-peptide, followed by the receptor-binding domain. In contrast to prototypical single-chain AB toxins, AIP56 does not comprise a typical structurally complex translocation domain; instead, the elements involved in translocation are scattered across its domains. Thus, the catalytic domain contains a helical hairpin that serves as a molecular switch for triggering the conformational changes necessary for membrane insertion only upon endosomal acidification, whereas the middle and receptor-binding domains are required for pore formation.

Early innate immune responses in European sea bass (Dicentrarchus labrax L.) following Tenacibaculum maritimum infection.

Introduction: The marine aquaculture industry has been witnessing a worldwide emergence of tenacibaculosis, a poorly understood bacterial disease caused by Tenacibaculum maritimum that affects commercially important fish. So far, knowledge on the T. maritimum virulence mechanisms is scarce and the pathogen-host interaction operating in tenacibaculosis remain to be disclosed. This study aimed at contributing to a better understanding of this disease, by evaluating the early innate immune response triggered in European sea bass (Dicentrarchus labrax) by a bath-challenge with T. maritimum. Methods: Groups of sea bass were bath-challenged with T. maritimum (challenged fish) or mock-challenged. Undisturbed fish were used as controls (time 0). Samples of blood, liver and mucosal organs (skin, gills and posterior-intestine) were collected at 0 h (control) and at 6, 24, 48 and 72 h post-challenge (n=12). Mucosal organs were used for analyzing the expression of immune-related genes by RT-qPCR, as well as blood samples for assessing haematological and innate humoral parameters and liver for oxidative stress assessment. Results: An increased expression of il-1ß, il8, mmp9 and hamp1 was detected in all mucosal organs of infected fish when compared with control and mock-challenged fish, suggesting a pro-inflammatory response against T. maritimum transversal to all organs. The faster induction of these pro-inflammatory genes was observed in the gills. Regarding the systemic response, challenged fish presented neutrophilia, monocytosis, signs of anemia, and a decrease of bactericidal and lysozyme activities in plasma. Almost no variations were observed regarding hepatic oxidative stress. Discussion/Conclusions: The present study suggests that T. maritimum induces a local innate immune response upon bath infection not only in the skin of European sea bass, but also in the gills and posterior-intestine, likely triggered by the T. maritimum's capacity to adhere, colonize and damage these organs that can function as entry ways to bacteria, leading ultimately to the seen host's systemic response.

Comparison of Zinc Oxide Nanoparticle Integration into Non-Woven Fabrics Using Different Functionalisation Methods for Prospective Application as Active Facemasks.

The development of advanced facemasks stands out as a paramount priority in enhancing healthcare preparedness. In this work, different polypropylene non-woven fabrics (NWF) were characterised regarding their structural, physicochemical and comfort-related properties. The selected NWF for the intermediate layer was functionalised with zinc oxide nanoparticles (ZnO NPs) 0.3 and 1.2wt% using three different methods: electrospinning, dip-pad-dry and exhaustion. After the confirmation of ZnO NP content and distribution within the textile fibres by morphological and chemical analysis, the samples were evaluated regarding their antimicrobial properties. The functionalised fabrics obtained via dip-pad-dry unveiled the most promising data, with 0.017 ± 0.013wt% ZnO NPs being mostly located at the fibre's surface and capable of total eradication of Staphylococcus aureus and Escherichia coli colonies within the tested 24 h (ISO 22196 standard), as well as significantly contributing (**** p < 0.0001) to the growth inhibition of the bacteriophage MS2, a surrogate of the SARS-CoV-2 virus (ISO 18184 standard). A three-layered structure was assembled and thermoformed to obtain facemasks combining the previously chosen NWF, and its resulting antimicrobial capacity, filtration efficiency and breathability (NP EN ISO 149) were assessed. The developed three-layered and multiscaled fibrous structures with antimicrobial capacities hold immense potential as active individual protection facemasks.

Low salinity activates a virulence program in the generalist marine pathogen Photobacterium damselae subsp. damselae.

Facultative marine bacterial pathogens sense environmental signals so that the expression of virulence factors is upregulated on entry into hosts and downregulated during the free-living lifestyle in the environment. In this study, we utilized transcriptome sequencing to compare the transcriptional profiles of Photobacterium damselae subsp. damselae, a generalist pathogen that causes disease in diverse marine animals and fatal infections in humans at NaCl concentrations that mimic the free-living lifestyle or host internal milieu, respectively. We here show that NaCl concentration constitutes a major regulatory signal that shapes the transcriptome and uncover 1,808 differentially expressed genes (888 upregulated and 920 downregulated in response to low-salt conditions). Growth at 3% NaCl, a salinity that mimics the free-living lifestyle, upregulated genes involved in energy production, nitrogen metabolism, transport of compatible solutes, utilization of trehalose and fructose, and carbohydrate and amino acid metabolism with strong upregulation of the arginine deiminase system (ADS). In addition, we observed a marked increase in resistance to antibiotics at 3% NaCl. On the contrary, the low salinity conditions (1% NaCl) that mimic those encountered in the host triggered a virulence gene expression profile that maximized the production of the type 2 secretion system (T2SS)-dependent cytotoxins damselysin, phobalysin P, and a putative PirAB-like toxin, observations that were corroborated by the analysis of the secretome. Low salinity also upregulated the expression of iron-acquisition systems, efflux pumps, and other functions related to stress response and virulence. The results of this study greatly expand our knowledge of the salinity-responsive adaptations of a generalist and versatile marine pathogen. IMPORTANCE Pathogenic Vibrionaceae species experience continuous shifts of NaCl concentration in their life cycles. However, the impact of salinity changes in gene regulation has been studied in a small number of Vibrio species. In this study, we analyzed the transcriptional response of Photobacterium damselae subsp. damselae (Pdd), a generalist and facultative pathogen, to changes in salinity, and demonstrate that growth at 1% NaCl in comparison to 3% NaCl triggers a virulence program of gene expression, with a major impact in the T2SS-dependent secretome. The decrease in NaCl concentration encountered by bacteria on entry into a host is proposed to constitute a regulatory signal that upregulates a genetic program involved in host invasion and tissue damage, nutrient scavenging (notably iron), and stress responses. This study will surely inspire new research on Pdd pathobiology, as well as on other important pathogens of the family Vibrionaceae and related taxa whose salinity regulons still await investigation.

CtBP Neuroprotective Role in Toxin-Based Parkinson's Disease Models: From Expression Pattern to Dopaminergic Survival.

C-terminal binding proteins (CtBP) are transcriptional co-repressors regulating gene expression. CtBP promote neuronal survival through repression of pro-apoptotic genes, and may represent relevant targets for neurodegenerative disorders, such as Parkinson's disease (PD). Nevertheless, evidence of the role of CtBP1 and CtBP2 in neurodegeneration are scarce. Herein, we showed that CtBP1 and CtBP2 are expressed in neurons, dopaminergic neurons, astrocytes, and microglia in the substantia nigra (SN) and striatum of adult mice. Old mice showed a lower expression of CtBP1 in the SN and higher expression of CtPB2 in the SN and striatum compared with adult mice. In vivo models for PD (paraquat, MPTP, 6-OHDA) showed increased expression of CtBP1 in the SN and striatum while CtBP2 expression was increased in the striatum of paraquat-treated rats only. Moreover, an increased expression of both CtBP was found in a dopaminergic cell line (N27) exposed to 6-OHDA. In the 6-OHDA PD model, we found a dual effect using an unspecific ligand of CtBP, the 4-methylthio 2-oxobutyric acid (MTOB): higher concentrations (e.g. 2500 µM, 1000 µM) inhibited dopaminergic survival, while at 250 µM it counteracted cell death. In vitro, this latter protective role was absent after the siRNA silencing of CtBP1 or CtBP2. Altogether, this is the first report exploring the cellular and regional expression pattern of CtBP in the nigrostriatal pathway and the neuroprotective role in PD toxin-based models. CtBP could counteract dopaminergic cell death in the 6-OHDA PD model and, therefore, CtBP function and therapeutic potential in PD should be further explored.

Characterization and Vaccine Potential of Outer Membrane Vesicles from Photobacterium damselae subsp. piscicida.

Photobacterium damselae subsp. piscicida (Phdp) is a Gram-negative fish pathogen with worldwide distribution and broad host specificity that causes heavy economic losses in aquaculture. Although Phdp was first identified more than 50 years ago, its pathogenicity mechanisms are not completely understood. In this work, we report that Phdp secretes large amounts of outer membrane vesicles (OMVs) when cultured in vitro and during in vivo infection. These OMVs were morphologically characterized and the most abundant vesicle-associated proteins were identified. We also demonstrate that Phdp OMVs protect Phdp cells from the bactericidal activity of fish antimicrobial peptides, suggesting that secretion of OMVs is part of the strategy used by Phdp to evade host defense mechanisms. Importantly, the vaccination of sea bass (Dicentrarchus labrax) with adjuvant-free crude OMVs induced the production of anti-Phdp antibodies and resulted in partial protection against Phdp infection. These findings reveal new aspects of Phdp biology and may provide a basis for developing new vaccines against this pathogen.

Word reading skills in autism spectrum disorder: A systematic review.

A growing body of research suggests that children with autism spectrum disorder (ASD) are at risk of reading and learning difficulties. However, there is mixed evidence on their weaknesses in different reading components, and little is known about how reading skills characterize in ASD. Thereby, the current study aimed to systematically review the research investigating this function in children with ASD. To this purpose, we reviewed 24 studies that compared (1) children with ASD and children with typical development (TD) in word and nonword reading performance, (2) children with ASD and normative data of word and nonword reading tests, and (3) the results obtained by children with ASD in word and nonword reading tests. Most of the comparisons (62%) contrasting the reading performance of children with ASD and children with TD did not find significant differences between groups in both word and nonword reading. However, all the comparisons that reported standardized results showed that children with ASD had scores that fell within population norms. Regarding the third comparison of interest, about 54% of the studies presented data for both word and nonword reading, but only one study tested the difference between them and showed that children with ASD had higher levels of word than of nonword reading. Despite these results, the heterogeneous and small samples do not allow to draw sound conclusions regarding the strategies that children with ASD use to read words. As consequence, the nature of reading difficulties presented by children with ASD are still unknown, requiring future research conducted with larger and well-characterized samples of ASD and TD, using homogeneous specific tasks designed to assess word reading strategies.

Observational study on medication administration errors at a University Hospital in Brazil: incidence, nature and associated factors.

BACKGROUND: Medication administration errors are frequent and cause significant harm globally. However, only a few data are available on their prevalence, nature, and severity in developing countries, particularly in Brazil. This study attempts to determine the incidence, nature, and factors associated with medication administration errors observed in a university hospital. METHODS: This was a prospective observational study, conducted in a clinical and surgical unit of a University Hospital in Brazil. Two previously trained professionals directly observed medication preparation and administration for 15 days, 24 h a day, in February 2020. The type of error, the category of the medication involved, according to the anatomical therapeutic chemical classification system, and associated risk factors were analyzed. Multivariate logistic regression was adopted to identify factors associated with errors. RESULTS: The administration of 561 drug doses was observed. The mean total medication administration error rate was 36.2% (95% confidence interval 32.3-40.2). The main factors associated with time errors were interruptions. Regarding technique errors, the primary factors observed were the route of administration, interruptions, and workload. CONCLUSIONS: Here, we identified a high total medication administration error rate, the most frequent being technique, wrong time, dose, and omission errors. The factors associated with errors were interruptions, route of administration and workload, which agrees well with the results of other national and international studies.

Chemical Composition of the "Galo de Barcelos" (Barcelos Rooster Raw Meat).

Ten roosters produced according to "Barcelos Confraria" rules and ten roosters of autochthonous "Amarela" breed, reared on a similar traditional production system, were analyzed, and the chemical profile of two of the most significant meat portions, breast and drumstick, was determined. The results demonstrated that the "Barcelos" rooster raw meat is rich in proteins (22.3%) and fat (4.31%), particularly in monounsaturated fatty acids (39.1%). Significant differences (p ≤ 0.01) were observed, with the breast having a higher protein content (25.1 vs. 19.7%) and less fat (1.9% vs. 6.7%), compared to the drumstick. The fatty acid profile revealed (SFA 30.0%, MUFA 39.1%, and PUFA 24.6%) a similar composition to the roosters reared in the traditional or organic production systems, such as the "Amarela" autochthonous rooster. The "Barcelos" rooster can be regarded as a highly nutritional meat, with an interesting chemical profile ensuring a high-quality traditional product to consumers.

IBRORS-MCL study: a Spanish retrospective and observational study of relapsed/refractory mantle-cell lymphoma treated with ibrutinib in routine clinical practice.

This retrospective study evaluated 66 patients diagnosed with relapsed and/or refractory mantle cell lymphoma (R/R MCL) treated with ibrutinib in Spain in routine clinical practice. At diagnosis, patients had a median age of 64.5 years, 63.6% presented with intermediate/high sMIPI (simplified prognostic index for advanced-stage mantle cell lymphoma), 24.5% had the blastoid variant, and 55.6% had a Ki67 > 30%. Patients had received a median of 2 prior lines of therapy (range 1-2; min-max 1-7). Overall response rate was 63.5%, with 38.1% of patients achieving complete response (CR). With a median duration of ibrutinib exposure of 10.7 months (range 5.2-19.6; min-max 0.3-36), the median progression-free survival (PFS) and overall survival (OS) were 20 months [95% confidence interval (CI) 8.8-31.1] and 32 months (95% CI 22.6-41.3), respectively, and were not reached in patients achieving CR. No grade ≥ 3 cardiovascular toxicity or bleeding was reported. This study supports that treatment with ibrutinib leads to high response rates and favorable survival outcomes in patients with R/R MCL.

Antimicrobial resistance in Escherichia coli isolated from on-farm and conventional hatching broiler farms in Ireland.

BACKGROUND: On-farm hatching (OH) systems are becoming more common in broiler production. Hatching conditions differ from conventional farms as OH chicks avoid exposure to handling, transport, post-hatch water and feed deprivation. In contrast, chicks in conventional hatching conditions (CH) are exposed to standard hatchery procedures and transported post hatching. The objectives of this pilot study were to investigate the prevalence and frequency of Escherichia coli resistant to antimicrobials, including presumptive ESBL/AmpC-producing E. coli, isolated from environmental and faecal samples from OH versus CH hatching systems, and to investigate the presence of ESBL/AmpC-producing encoding genes. RESULTS: Environmental samples were collected from one flock in 10 poultry farms (5 OH farms, 5 CH farms) on day 0 post disinfection of the facilities to assess hygiene standards. On D10 and D21 post egg/chick arrival onto the farm, samples of faeces, boot swabs and water drinker lines were collected. E. coli were isolated on MacConkey agar (MC) and MacConkey supplemented with cefotaxime (MC+). Few E. coli were detected on D0. However, on D10 and D21 E. coli isolates were recovered from faeces and boot swabs. Water samples had minimal contamination. In this study, 100% of cefotaxime resistant E. coli isolates (n=33) detected on selective media and 44% of E. coli isolates (84/192) detected on nonselective media were multidrug resistant (MDR). The antimicrobial resistance (AMR) genotype for the 15 ESBL/AmpC producing isolates was determined using multiplex PCR. Six of these were selected for Sanger sequencing of which two were positive for blaCMY-2, two for blaTEM-1 and two were positive for both genes. CONCLUSIONS: There was no difference in E. coli isolation rates or prevalence of AMR found between the OH versus CH systems, suggesting that the OH system may not be an additional risk of resistant E. coli dissemination to broilers compared to the CH systems. The frequency of ß-lactam resistant E. coli in boot swab and faeces samples across both OH (24/33 (73%)) and CH (9/33 (27%)) systems may indicate that hatcheries could be a reservoir and major contributor to the transmission of AMR bacteria to flocks after entry to the rearing farms.

Susceptibility of Sea Bream (Sparus aurata) to AIP56, an AB-Type Toxin Secreted by Photobacterium damselae subsp. piscicida.

Photobacterium damselae subsp. piscicida (Phdp) is a Gram-negative bacterium that infects a large number of marine fish species in Europe, Asia, and America, both in aquacultures and in the natural environment. Among the affected hosts are economically important cultured fish, such as sea bream (Sparus aurata), sea bass (Dicentrarchus labrax), yellowtail (Seriola quinqueradiata), and cobia (Rachycentron canadum). The best characterized virulence factor of Phdp is the Apoptosis-Inducing Protein of 56 kDa (AIP56), a secreted AB-type toxin that has been shown to induce apoptosis of sea bass phagocytes during infection. AIP56 has an A subunit that displays metalloprotease activity against NF-kB p65 and a B subunit that mediates binding and internalization of the A subunit in susceptible cells. Despite the fact that the aip56 gene is highly prevalent in Phdp isolates from different fish species, the toxicity of AIP56 has only been studied in sea bass. In the present study, the toxicity of AIP56 for sea bream was evaluated. Ex vivo assays showed that sea bream phagocytes are resistant to AIP56 cytotoxicity and that resistance was associated with an inefficient internalization of the toxin by those cells. Accordingly, in vivo intoxication assays revealed that sea bream is much more resistant to AIP56-induced lethality than sea bass. These findings, showing that the effect of AIP56 is different in sea bass and sea bream, set the basis for future studies to characterize the effects of AIP56 and to fully elucidate its virulence role in different Phdp susceptible hosts.

Exploiting Polyelectrolyte Complexation for the Development of Adhesive and Bioactive Membranes Envisaging Guided Tissue Regeneration.

Mussels secrete protein-based byssal threads to tether to rocks, ships, and other organisms underwater. The secreted marine mussel adhesive proteins (MAPs) contain the peculiar amino acid L-3,4-dihydroxyphenylalanine (DOPA), whose catechol group content contributes greatly to their outstanding adhesive properties. Inspired by such mussel bioadhesion, we demonstrate that catechol-modified polysaccharides can be used to obtain adhesive membranes using the compaction of polyelectrolyte complexes (CoPEC) method. It is a simple and versatile approach that uses polyelectrolyte complexes as building blocks that coalesce and dry as membrane constructs simply as a result of sedimentation and mild temperature. We used two natural and biocompatible polymers: chitosan (CHI) as a polycation and hyaluronic acid (HA) as a polyanion. The CoPEC technique also allowed the entrapment of ternary bioactive glass nanoparticles to stimulate mineralization. Moreover, combinations of these polymers modified with catechol groups were made to enhance the adhesive properties of the assembled membranes. Extensive physico-chemical characterization was performed to investigate the successful production of composite CoPEC membranes in terms of surface morphology, wettability, stability, mechanical performance, in vitro bioactivity, and cellular behavior. Considering the promising properties exhibited by the obtained membranes, new adhesives suitable for the regeneration of hard tissues can be envisaged.

Poly(Lactic Acid)/Graphite Nanoplatelet Nanocomposite Filaments for Ligament Scaffolds.

The anterior cruciate ligament (ACL) is one of the most prone to injury in the human body. Due to its insufficient vascularization and low regenerative capacity, surgery is often required when it is ruptured. Most of the current tissue engineering (TE) strategies are based on scaffolds produced with fibers due to the natural ligament's fibrous structure. In the present work, composite filaments based on poly(L-lactic acid) (PLA) reinforced with graphite nanoplatelets (PLA+EG) as received, chemically functionalized (PLA+f-EG), or functionalized and decorated with silver nanoparticles [PLA+((f-EG)+Ag)] were produced by melt mixing, ensuring good filler dispersion. These filaments were produced with diameters of 0.25 mm and 1.75 mm for textile-engineered and 3D-printed ligament scaffolds, respectively. The resulting composite filaments are thermally stable, and the incorporation of graphite increases the stiffness of the composites and decreases the electrical resistivity, as compared to PLA. None of the filaments suffered significant degradation after 27 days. The composite filaments were processed into 3D scaffolds with finely controlled dimensions and porosity by textile-engineered and additive fabrication techniques, demonstrating their potential for ligament TE applications.

The two-component system RstAB regulates production of a polysaccharide capsule with a role in virulence in the marine pathogen Photobacterium damselae subsp. damselae.

The marine bacterium Photobacterium damselae subsp. damselae (Pdd) causes disease in marine animals and humans. Previous studies demonstrated that mutation of the two-component system RstAB strongly impacts virulence of this pathogen, but the RstAB regulon has not been thoroughly elucidated. We here compared the transcriptomes of Pdd RM-71 and ΔrstA and ΔrstB derivatives using RNA-seq. In accordance with previous studies, RstAB positively regulated cytotoxins Dly, PhlyP and PhlyC. This analysis also demonstrated a positive regulation of outer membrane proteins, resistance against antimicrobials and potential virulence factors by this system. Remarkably, RstAB positively regulated two hitherto uncharacterised gene clusters involved in the synthesis of a polysaccharide capsule. Presence of a capsular layer in wild-type cells was confirmed by transmission electron microscopy, whereas rstA and rstB mutants were non-capsulated. Mutants for capsule synthesis genes, wza and wzc exhibited acapsular phenotypes, were impaired in resistance against the bactericidal action of fish serum and mucus, and were strongly impaired in virulence for fish, indicating a major role of capsule in virulence. Collectively, this study demonstrates that RstAB is a major positive regulator of key virulence factors including a polysaccharide capsule essential for full virulence in a pathogenic Photobacterium.

Predictors for incomplete response to ursodeoxycholic acid in primary biliary cholangitis. Data from a national registry of liver disease.

BACKGROUND: The current standard of treatment in primary biliary cholangitis (PBC) is ursodeoxycholic acid (UDCA), although a considerable proportion of patients show incomplete response resulting in disease progression. OBJECTIVE: This study aimed to assess the prevalence of incomplete response to UDCA and determine associated patients' characteristics. METHODS: Patients with PBC as main diagnosis were included from a national multicentric patient registry-Liver.pt. Main endpoints included incomplete response to UDCA treatment according to Barcelona, Paris I and Paris II criteria, Globe and UK PBC scores and the association between baseline characteristics and incomplete response according to Paris II criteria. RESULTS: A total of 434 PBC patients were identified, with a mean age of 55 years and 89.2% females. Nearly half of patients were asymptomatic at diagnosis and 93.2% had positive anti-mitochondrial antibodies. Almost all patients (95.6%) had been prescribed at least one drug for PBC treatment. At the last follow-up visit, 93.3% were under treatment of which 99.8% received UDCA. Incomplete response to UDCA was observed in 30.7%, 35.3%, 53.7% and 36.4% of patients according to Barcelona, Paris I, Paris II criteria and Globe score, respectively. After adjusting for age and sex, and accordingly to Paris II criteria, the risk for incomplete biochemical response was 25% higher for patients with cirrhosis at diagnosis (odds ratio [OR] = 1.25; 95% confidence interval [95%CI]: 1.02-1.54; p = 0.033) and 35% (95%CI:1.06-1.72; p = 0.016) and 5% (OR = 1.05; 95%CI:1.01-1.10; p = 0.013) for those with elevated gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP). CONCLUSION: A considerable proportion of patients showed incomplete biochemical response to UDCA treatment according to Paris II criteria. Cirrhosis, elevated GGT and ALP at diagnosis were identified as associated risk factors for incomplete response. Early identification of patients at risk of incomplete response could improve treatment care and guide clinical decision to a more careful patient monitorization.