Synthesis and Photophysical Properties of Bipolar Compound: Triphenylamine/Diazafluorene-Carbazole.

Carbazole and triphenylamine, are two well-known hole transporting units that are attached to electron transporting unit 4,5-diazafluorene in a fascinating way to bring out non-planar configuration of a molecule. The synthesized compound exhibits good thermal stability (Td > 515 °C) and high glass transition temperature (Tg, 191 °C). Optical bandgap (Egopt) obtained from solid state absorption spectra was calculated to be 2.93 eV. Solid state photoluminescence spectra displays the emission maxima at 473 nm. The emission characteristics of the compound observed in solvents of different polarity confirms the existence of intramolecular charge transfer in their excited state. Density functional theory studies reveal that HOMO and HOMO-1 localized on triphenylamine is spatially separated from LUMO of 4,5-diazafluorene, which manifest its bipolar character. The realization of long lived charge separated state upon photo-excitation from time resolved photoluminescence studies ascertains the charge transfer from triphenylamine to 4,5-diazafluorene. The experimental and theoretical analysis of the compound proved it to be a promising candidate for the fabrication of OLED devices.

Sublethal neurotoxicity of saxitoxin in early zebrafish development: Impact on sensorimotor function and neurotransmission systems.

Saxitoxin (STX) represents a marine toxin of significant concern due to its deleterious implications for aquatic ecosystems and public food safety. As a potent paralytic agent, the role of STX in obstructing voltage-gated sodium channels (VGSCs) is well-characterized. Yet, the mechanistic details underlying its low-dose toxicity remain largely enigmatic. In the current study, zebrafish embryos and larvae were subjected to subchronic exposure of graded STX concentrations (0, 1, 10, and 100 µg/L) until the 7th day post-fertilization. A tactile stimulus-based assay was employed to evaluate potential behavioral perturbations resulting from STX exposure. Both behavioral and transcription level analyses unveiled a compromised tactile response, which was found to be associated with a notable upregulation in the mRNA of two distinct VGSC isoforms, specifically the scn8aa/ab and scn1Laa/ab transcripts, even at the minimal STX dose. Notably, exposure to this lowest STX concentration also resulted in alterations in the transcriptional patterns of pivotal genes for cholinergic and GABAergic pathways, including ache and gabra1. Furthermore, STX induced a marked decrease in the levels of the neurotransmitter GABA. Our findings underscore that prolonged low-dose STX exposure during early development can significantly compromise the tactile response behavior in zebrafish. This study reveals that chronic low-dose STX exposure of developing zebrafish alters neurotransmission pathways that converge on altered tactile behavior.

Increase of catastrophic and impoverishing health expenditures in Mexico associated to policy changes and the COVID-19 pandemic.

Background: In 2003, the Mexican Congress approved a major reform to provide health care services to the poor population through the public insurance scheme Seguro Popular. This program was dismantled in 2019 as part of a set of health system reforms and substituted with the Health Institute for Welfare (INSABI). These changes were implemented during the initial phases of the coronavirus (COVID-19) pandemic. We aimed to examine the impact of these reforms and the COVID-19 pandemic on financial risk protection in Mexico between 2018 and 2020. Methods: We performed a population-based analysis using cross-sectional data from the 2018 and 2020 rounds of the National Household Income and Expenditures Survey. We used a pooled fixed-effects multivariable two-stage probit model to determine the likelihood of catastrophic health expenditure (CHE), impoverishing health expenditure (IHE), and excessive health expenditure (EHE) among Mexican households. We also mapped the quintiles of changes in EHE in households without health insurance by state. Results: The percentage of households without health insurance almost doubled from 8.8% (three million households) in 2018 to 16.5% (5.8 million households) in 2020. We also found large increases in the proportion of households incurring in CHE (18.4%; 95% confidence interval (CI) = 6.1, 30.7) and EHE (18.7%; 95% CI = 7.9, 29.5). Significant increases in CHE, IHE, and EHE were only observed among households without health insurance (CHE: 90.7%; 95% CI = 31.6, 149.7, EHE: 73.5%; 95% CI = 25.3, 121.8). Virtually all Mexican states (n/N = 31/32) registered an increase in EHE among households without health insurance. This increase has a systematic territorial component affecting mostly central and southern states (range = -1.0% to 194.4%). Conclusions: The discontinuation of the Seguro Popular Program and its substitution with INSABI during the first stages of the COVID-19 pandemic reduced the levels of health care coverage in Mexico. This reduction and the pandemic increased out-of-pocket expenditure in health and the portion of CHE and EHE in the 2018-2020 period. The effect was higher in households without health insurance and households in central and southern states of the country. Further studies are needed to determine the specific effect both of recent policy changes and of the COVID-19 pandemic on the levels of financial protection in health in Mexico.

Catalytic Selective Oxidation of ß-O-4 Bond in Phenethoxybenzene as a Lignin Model Using (TBA)5[PMo10V2O40] Nanocatalyst: Optimization of Operational Conditions.

The catalytic oxidation of phenethoxybenzene as a lignin model compound with a ß-O-4 bond was conducted using the Keggin-type polyoxometalate nanocatalyst (TBA)5[PMo10V2O40]. The optimization of the process's operational conditions was carried out using response surface methodology. The statistically significant variables in the process were determined using a fractional factorial design. Based on this selection, a central circumscribed composite experimental design was used to maximize the phenethoxybenzene conversion, varying temperature, reaction time, and catalyst load. The optimal conditions that maximized the phenethoxybenzene conversion were 137 °C, 3.5 h, and 200 mg of catalyst. In addition, under the optimized conditions, the Kraft lignin catalytic depolymerization was carried out to validate the effectiveness of the process. The depolymerization degree was assessed by gel permeation chromatography from which a significant decrease in the molar mass distribution Mw from 7.34 kDa to 1.97 kDa and a reduction in the polydispersity index PDI from 6 to 3 were observed. Furthermore, the successful cleavage of the ß-O-4 bond in the Kraft lignin was verified by gas chromatography-mass spectrometry analysis of the reaction products. These results offer a sustainable alternative to efficiently converting lignin into valuable products.

The ferryl generation by fenton reaction driven by catechol.

The Fenton and Fenton-like reactions are based on the decomposition of hydrogen peroxide catalyzed by Fe(II), primarily producing highly oxidizing hydroxyl radicals (HO∙). While HO∙ is the main oxidizing species in these reactions, Fe(IV) (FeO2+) generation has been reported as one of the primary oxidants. FeO2+ has a longer lifetime than HO∙ and can remove two electrons from a substrate, making it a critical oxidant that may be more efficient than HO∙. It is widely accepted that the preferential generation of HO∙ or FeO2+ in the Fenton reaction depends on factors such as pH and Fe: H2O2 ratio. Reaction mechanisms have been proposed to generate FeO2+, which mainly depend on the radicals generated in the coordination sphere and the HO∙ radicals that diffuse out of the coordination sphere and react with Fe(III). As a result, some mechanisms are dependent on prior HO∙ radical production. Catechol-type ligands can induce and amplify the Fenton reaction by increasing the generation of oxidizing species. Previous studies have focused on the generation of HO∙ radicals in these systems, whereas this study investigates the generation of FeO2+ (using xylidine as a selective substrate). The findings revealed that FeO2+ production is increased compared to the classical Fenton reaction and that FeO2+ generation is mainly due to the reactivity of Fe(III) with HO∙ from outside the coordination sphere. It is proposed that the inhibition of FeO2+ generation via HO∙ generated from inside the coordination sphere is caused by the preferential reaction of HO∙ with semiquinone in the coordination sphere, favoring the formation of quinone and Fe(III) and inhibiting the generation of FeO2+ through this pathway.

Stress, Sport Anxiety, Neuroticism, and Coping in Student-Athletes: Implications for Patient Mental Health.

CONTEXT: Patients' mental health has been recognized as important in providing patient-centered care in athletic training. OBJECTIVE: To evaluate stress, sport anxiety, neuroticism, and coping in student-athletes. DESIGN: Cross-sectional study. SETTING: University athletics. PATIENTS OR OTHER PARTICIPANTS: The sample comprised 86 student-athletes competing in National Collegiate Athletic Association (NCAA) Division III. MAIN OUTCOME MEASURE(S): The Perceived Stress Scale, Sport Anxiety Scale-2, neuroticism scale of the Big Five Inventory, and Brief COPE were used to measure stress, sport anxiety, neuroticism, and coping, respectively. RESULTS: Sport anxiety was positively related to stress (r = 0.446, P < .001) and neuroticism (r = 0.311, P < .01) and not related to emotion-focused coping (r = 0.270, P = .804). Neuroticism was a negative predictor of emotion-focused coping (b = -0.373, P < .001), and sport anxiety and stress were predictors of dysfunctional coping (b = 0.120, P < .05; b = 0.037, P < .05). Stress, sport anxiety, and neuroticism were not predictors of problem-focused coping. CONCLUSIONS: Support was evident for the relationship among stress, sport anxiety, neuroticism, and coping in NCAA Division III student-athletes. Such results warrant future exploration to inform behavioral interventions targeting student-athlete psychosocial factors to promote improved performance, reduce injury risk factors (eg, stress, personality, coping), and enhance student-athlete mental health and well-being.

Combined use of novel chitosan-grafted N-hydroxyethyl acrylamide polyurethane and human dermal fibroblasts as a construct for in vitro-engineered skin.

A rich plethora of information about grafted chitosan (CS) for medical use has been reported. The capability of CS-grafted poly(N-hydroxyethyl acrylamide) (CS-g-PHEAA) to support human dermal fibroblasts (HDFs) in vitro has been proven. However, CS-grafted copolymers lack good stiffness and the characteristic microstructure of a cellular matrix. In addition, whether CS-g-PHEAA can be used to prepare a scaffold with a suitable morphology and mechanical properties for skin tissue engineering (STE) is unclear. This study aimed to show for the first time that step-growth polymerizations can be used to obtain polyurethane (PU) platforms of CS-g-PHEAA, which can also have enhanced microhardness and be suitable for in vitro cell culture. The PU prepolymers were prepared from grafted CS, polyethylene glycol, and 1,6-hexamethylene diisocyanate. The results proved that a poly(saccharide-urethane) [(CS-g-PHEAA)-PU] could be successfully synthesized with a more suitable microarchitecture, thermal properties, and topology than CS-PU for the dynamic culturing of fibroblasts. Cytotoxicity, proliferation, histological and immunophenotype assessments revealed significantly higher biocompatibility and cell proliferation of the derivative concerning the controls. Cells cultured on (CS-g-PHEAA)-PU displayed a quiescent state compared to those cultured on CS-PU, which showed an activated phenotype. These findings may be critical factors in future studies establishing wound dressing models.

Berberis microphylla G. Forst Intake Reduces the Cardiovascular Disease Plasmatic Markers Associated with a High-Fat Diet in a Mice Model.

Polyphenols are bioactive substances that participate in the prevention of chronic illnesses. High content has been described in Berberis microphylla G. Forst (calafate), a wild berry extensively distributed in Chilean-Argentine Patagonia. We evaluated its beneficial effect through the study of mouse plasma metabolome changes after chronic consumption of this fruit. Characterized calafate extract was administered in water, for four months, to a group of mice fed with a high-fat diet and compared with a control diet. Metabolome changes were studied using UHPLC-DAD-QTOF-based untargeted metabolomics. The study was complemented by the analysis of protein biomarkers determined using Luminex technology, and quantification of OH radicals by electron paramagnetic resonance spectroscopy. Thirteen features were identified with a maximum annotation level-A, revealing an increase in succinic acid, activation of tricarboxylic acid and reduction of carnitine accumulation. Changes in plasma biomarkers were related to inflammation and cardiovascular disease, with changes in thrombomodulin (-24%), adiponectin (+68%), sE-selectin (-34%), sICAM-1 (-24%) and proMMP-9 (-31%) levels. The production of OH radicals in plasma was reduced after calafate intake (-17%), especially for the group fed with a high-fat diet. These changes could be associated with protection against atherosclerosis due to calafate consumption, which is discussed from a holistic and integrative point of view.

Post-weaning social isolation increases the incentive value of nicotine-related contexts and decreases the accumulation of ΔFosB in nucleus accumbens in adolescent rats.

Adolescent social conditions profoundly affect vulnerability to drug abuse. Preclinical studies have shown that preventing social interactions during adolescence increases the rewarding effects of drugs like alcohol, cocaine, or amphetamines, however, little data exist regarding the impact of social isolation on nicotine effects. The current study evaluated the effects of differential rearing conditions during adolescence (isolation or group rearing) on (1) conditioned place preference induced by low nicotine doses (0.1 or 0.3 mg/kg) and (2) sensitization to the locomotor effects of nicotine after sub-chronic administration (3) and accumulation of ΔFosB in nucleus accumbens (NAc). Results showed that nicotine induced place preference in isolated and grouped rats, but the effect was more persistent for the rats reared in isolation. Isolated reared rats also exhibited lower levels of ΔFosB accumulation in NAc. No differences were found in the behavioral sensitization to nicotine effects between rearing conditions. The results suggest that isolation engenders a more robust incentive value of nicotine-related contexts. This effect could be related to the basal expression of ΔFosB: lower levels of this transcription factor seem to impair the motivation of isolated reared rats and increase their vulnerability to the effects of drugs like nicotine.

Nanostructured electrochemical sensor applied to the electrocoagulation of arsenite in WWTP effluent.

A sensitive electroanalytical method for the determination of arsenite, based on a heterostructure of aminated multiwalled carbon nanotubes and gold nanoparticles, was applied in an electrocoagulation (EC) treatment for the elimination of arsenite. A sensitive quantitative response was obtained in the determination of As3+ in a secondary effluent from a wastewater treatment plant from Santiago (Chile). The preconcentration stage was optimized through a Central Composite Face design, and the most sensitive peak current was obtained at 200 s and -600 mV of time and accumulation potential, respectively, after a differential pulse voltammetry sweep. Electroanalytical determination was possible in an interval between 42.89 and 170.00 µg L-1 with a detection limit of 0.39 µg L-1, obtaining recoveries over 99.1%. The developed method was successfully applied in an electrocoagulation treatment to remove 250 µg L-1 of arsenite from a polluted effluent in a batch system. Complete arsenite removal was achieved using a steel EC system with a current density of 6.0 mA cm-2 in less than 3 min of treatment.

Influence of RE (Pr3+, Er3+, Nd3+) doping on structural, vibrational and enhanced persistent photocatalytic properties of ZnO nanostructures.

Rare earth (RE- Pr, Er and Nd) doped ZnO nanostructures were prepared through simple wet chemical precipitation route. The RE doping induced interesting morphological transition from spherical to flower like structures were analyzed. The X-ray diffraction (XRD) measurements revealed that the prepared materials were of highly crystalline in nature and RE dopant ions did not altered the crystal structure of ZnO. The microstrain of ZnO was altered with respect to the nature of dopants. In the case of the Pr doped ZnO, X-ray photoelectron spectroscopy (XPS) analysis confirmed that the dopant (Pr) ions successfully substituted in the ZnO lattice. Raman spectra revealed RE doping induced lower energy side shift and variation in intensity of the peaks related to the characteristic phonon modes of ZnO. In the case of Nd doped ZnO nanostructures, dopant induced suppression in classical Raman modes and evolution of multiphonon related modes were identified. Optical diffuse reflectance spectral (DRS) measurements, along with the characteristic excitonic band of ZnO, other bands associated to the transitions of 4f energy levels related to the RE ions were observed. The partially filled 4f orbitals led to the enhanced photocatalytic activity in RE doped ZnO nanostructures. The observed enhanced photocatalytic activity in RE doped ZnO when compared to bare ZnO was discussed. The decolorization efficiency of MB ensued the following order 96 > 94 > 86 > 78% for ZnErO, ZnNdO, ZnPrO and ZnO, respectively.

In vitro evaluation of the protective effect of crocin on human erythrocytes.

The interactions and the protective effect of the carotenoid crocin (CRO) on human erythrocytes (RBC) and molecular models of its membrane were investigated. The latter consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the RBC membrane, respectively. X-ray diffraction, differential scanning calorimetry (DSC) and electronic paramagnetic resonance spectroscopy (EPR) showed that CRO produced structural perturbations in DMPC bilayers and in isolated unsealed human erythrocyte membranes. On the other hand, scanning electron microscopy (SEM) showed that CRO induced shape changes in the RBC from their normal discoid form to echinocytes. This result indicates that the CRO molecules were mainly localized in the outer monolayer of the RBC membrane. The assessment of the protective capacity of CRO was revealed by the carotenoid inhibition of the morphological alterations caused by hypochlorous acid (HOCl) to RBC.

Piscirickettsia salmonis Produces a N-Acetyl-L-Homoserine Lactone as a Bacterial Quorum Sensing System-Related Molecule.

Piscirickettsia salmonis is the etiological agent of piscirickettsiosis, the most prevalent disease in salmonid species in Chilean salmonids farms. Many bacteria produce N-acyl-homoserine lactones (AHLs) as a quorum-sensing signal molecule to regulate gene expression in a cell density-dependent manner, and thus modulate physiological characteristics and several bacterial mechanisms. In this study, a fluorescent biosensor system method and gas chromatography-tandem mass spectrometry (GC/MS) were combined to detect AHLs produced by P. salmonis. These analyses revealed an emitted fluorescence signal when the biosensor P. putida EL106 (RPL4cep) was co-cultured with both, P. salmonis LF-89 type strain and an EM-90-like strain Ps007, respectively. Furthermore, the production of an AHL-type molecule was confirmed by GC/MS by both P. salmonis strains, which identified the presence of a N-acetyl-L-homoserine Lactone in the supernatant extract. However, It is suggested that an alternate pathway could synthesizes AHLs, which should be address in future experiments in order to elucidate this important bacterial process. To the best of our knowledge, the present report is the first to describe the type of AHLs produced by P. salmonis.

When You "Can't See" a Case of Relapsing Polychondritis.

Relapsing polychondritis (RP) is a rare and, if not treated, potentially lethal autoimmune disorder. Involvement of central nervous system (CNS) in RP is rare and, when present, makes it extremely difficult to diagnose. In this report, we present a case of a 22-year-old Hispanic woman who presented with sudden onset of headache and blurred vision. Magnetic resonance imaging (MRI) of her brain and orbit showed leptomeningeal enhancements in addition to asymmetrical thickening and enhancement of globes. Her lumbar puncture was consistent with aseptic meningitis picture, and she was placed on empirical treatment for presumptive CNS tuberculosis. Her vision deteriorated, and she was diagnosed with RP with CNS and ocular involvement and placed on high-dose steroids with dramatic rapid response. She has been on immunosuppressive treatment, including Sulfasalazine and Methotrexate, since then and her disease has been under control with decreased need for ophthalmic steroid drops. There have been only 19 previous cases found in literature reporting an association of RP with CNS involvement.

Prospects for increasing the utilization of cattle embryo transfer by small-scale milk and meat producers in tropical regions.

Small community cattle farmers in the tropics are facing challenges to deliver quality products whilst under pressure to increase milk and beef yields per cow. These challenges could be partially met by crossbreeding Bos taurus with Bos indicus (F1) cattle utilizing embryo transfer (ET) technology. The Bos taurus infusion would increase milk production, whilst the Bos indicus influence can improve resistance to the harsh environment of the tropics. Here, individuals from existing herds can be used to produce F1 embryos which benefit from hybrid vigour. Resultant female offspring would in turn receive an F1 embryo on reaching breeding maturity. This approach would help to provide a cost-effective, systematic approach to improve productivity in dairy and beef cattle in the tropics. However, full usage of ET, including in vitro applications, in the tropics will require improvements in procedures, resources and education.

Diabetic Muscle Infarction: Resolution of Rare Microangiopathy with Over-The-Counter Medication.

Diabetic muscle infarction (DMI) is a rare complication of poorly controlled type 1 and type 2 diabetes seen mostly in those who have already experienced microvascular complications. Currently, the incidence and prevalence of DMI are difficult to conclude, and there is no clear algorithm or standard of care in managing this condition. Pathogenesis of the microangiopathy of DMI remains unclear. A major finding in this investigation of DMI emphasizes that, within 2-17 weeks, patients who initiate low-dose acetylsalicylic acid, bed rest, and close outpatient follow-up see significant size reduction of lower extremity mass and complete resolution of pain without being subjected to invasive muscle biopsy.

Lemierre Syndrome in a Patient With Splenectomy Secondary to Pyruvate Kinase Deficiency, Complicated by Heparin Resistance.

Lemierre syndrome was first documented in the literature in 1936, and is defined as septic thrombophlebitis of the internal jugular vein. It is typically a result of oropharyngeal infection causing local soft tissue inflammation, which spreads to vasculature, and promotes formation of septic thrombi within the lumen, persistent bacteremia, and septic emboli. We present the case of a 24-year-old incarcerated man, who presented with leukocytosis and a right-sided tender, swollen neck after undergoing left mandibular molar extraction for an infected tooth. Computed tomography revealed a persistent thrombus in the transverse and sigmoid sinuses bilaterally, extending downwards, into the upper jugular veins. He was started on empiric intravenous vancomycin, zosyn, and heparin, but subsequently demonstrated heparin resistance, and was thus anticoagulated with a lovenox bridge to warfarin. Throughout his hospital course, hemocultures demonstrated no growth, so antibiotic treatment was deescalated to oral metronidazole and ceftriaxone. On discharge, the patient was transitioned to oral amoxicillin and metronidazole for an additional 4 weeks with continuation of anticoagulation with warfarin for a total of 3 to 6 months. This case report details a unique presentation of Lemierre syndrome with bilateral transverse sinus, sigmoid sinus, and internal jugular vein thrombosis that was presumably secondary to an odontogenic infectious focus.

Behavioural Fever Promotes an Inflammatory Reflex Circuit in Ectotherms.

BACKGROUND: The communication between the brain and the immune system is a cornerstone in animal physiology. This interaction is mediated by immune factors acting in both health and pathogenesis, but it is unclear how these systems molecularly and mechanistically communicate under changing environmental conditions. Behavioural fever is a well-conserved immune response that promotes dramatic changes in gene expression patterns during ectotherms' thermoregulatory adaptation, including those orchestrating inflammation. However, the molecular regulators activating the inflammatory reflex in ectotherms remain unidentified. METHODS: We revisited behavioural fever by providing groups of fish a thermal gradient environment during infection. Our novel experimental setup created temperature ranges in which fish freely moved between different thermal gradients: (1) wide thermoregulatory range; T° = 6.4 °C; and (2) restricted thermoregulatory range; T° = 1.4 °C. The fish behaviour was investigated during 5-days post-viral infection. Blood, spleen, and brain samples were collected to determine plasmatic pro- and anti-inflammatory cytokine levels. To characterize genes' functioning during behavioural fever, we performed a transcriptomic profiling of the fish spleen. We also measured the activity of neurotransmitters such as norepinephrine and acetylcholine in brain and peripheral tissues. RESULTS: We describe the first set of the neural components that control inflammatory modulation during behavioural fever. We identified a neuro-immune crosstalk as a potential mechanism promoting the fine regulation of inflammation. The development of behavioural fever upon viral infection triggers a robust inflammatory response in vivo, establishing an activation threshold after infection in several organs, including the brain. Thus, temperature shifts strongly impact on neural tissue, specifically on the inflammatory reflex network activation. At the molecular level, behavioural fever causes a significant increase in cholinergic neurotransmitters and their receptors' activity and key anti-inflammatory factors such as cytokine Il10 and Tgfß in target tissues. CONCLUSION: These results reveal a cholinergic neuronal-based mechanism underlying anti-inflammatory responses under induced fever. We performed the first molecular characterization of the behavioural fever response and inflammatory reflex activation in mobile ectotherms, identifying the role of key regulators of these processes. These findings provide genetic entry points for functional studies of the neural-immune adaptation to infection and its protective relevance in ectotherm organisms.

Perfusion Decellularization of Extrahepatic Bile Duct Allows Tissue-Engineered Scaffold Generation by Preserving Matrix Architecture and Cytocompatibility.

Reconstruction of bile ducts damaged remains a vexing medical problem. Surgeons have few options when it comes to a long segment reconstruction of the bile duct. Biological scaffolds of decellularized biliary origin may offer an approach to support the replace of bile ducts. Our objective was to obtain an extracellular matrix scaffold derived from porcine extrahepatic bile ducts (dECM-BD) and to analyze its biological and biochemical properties. The efficiency of the tailored perfusion decellularization process was assessed through histology stainings. Results from 4'-6-diamidino-2-phenylindole (DAPI), Hematoxylin and Eosin (H&E) stainings, and deoxyribonucleic acid (DNA) quantification showed proper extracellular matrix (ECM) decellularization with an effectiveness of 98%. Immunohistochemistry results indicate an effective decrease in immunogenic marker as human leukocyte antigens (HLA-A) and Cytokeratin 7 (CK7) proteins. The ECM of the bile duct was preserved according to Masson and Herovici stainings. Data derived from scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) showed the preservation of the dECM-BD hierarchical structures. Cytotoxicity of dECM-BD was null, with cells able to infiltrate the scaffold. In this work, we standardized a decellularization method that allows one to obtain a natural bile duct scaffold with hierarchical ultrastructure preservation and adequate cytocompatibility.

Overview of toxic cyanobacteria and cyanotoxins in Ibero-American freshwaters: Challenges for risk management and opportunities for removal by advanced technologies.

The increasing occurrence of cyanobacterial blooms worldwide represents an important threat for both the environment and public health. In this context, the development of risk analysis and management tools as well as sustainable and cost-effective treatment processes is essential. The research project TALGENTOX, funded by the Ibero-American Science and Technology Program for Development (CYTED-2019), aims to address this ambitious challenge in countries with different environmental and social conditions within the Ibero-American context. It is based on a multidisciplinary approach that combines ecology, water management and technology fields, and includes research groups from Chile, Colombia, Mexico, Peru and Spain. In this review, the occurrence of toxic cyanobacteria and cyanotoxins in freshwaters from these countries are summarized. The presence of cyanotoxins has been confirmed in all countries but the information is still scarce and further monitoring is required. In this regard, remote sensing or metagenomics are good alternatives at reasonable cost. The risk management of freshwaters from those countries considering the most frequent uses (consumption and recreation) has been also evaluated. Only Spain and Peru include cyanotoxins in its drinking water legislation (only MC-LR) and thus, there is a need for regulatory improvements. The development of preventive strategies like diminishing nutrient loads to aquatic systems is also required. In the same line, corrective measures are urgently needed especially in drinking waters. Advanced Oxidation Processes (AOPs) have the potential to play a major role in this scenario as they are effective for the elimination of most cyanotoxins classes. The research on the field of AOPs is herein summarized considering the cost-effectiveness, environmental character and technical applicability of such technologies. Fenton-based processes and photocatalysis using solar irradiation or LED light represent very promising alternatives given their high cost-efficiency. Further research should focus on developing stable long-term operation systems, addressing their scale-up.