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In this work we present a brief-review on the state of the art of hydrophilic or waterborne polyurethanes from their synthesis to their applications in biomedicine. The fundamentals of the synthesis are analyzed starting with the chemistry of isocyanates, structure-property relationship, most common commercially available reagents, and the isocyanate blocking reactions. Then, the applicability of polyurethanes in biomaterials is studied focusing on the formulation of hydrogels for wound healing and tissue engineering, as well as drug delivery applications.

A partir de dos intervenciones forenses se exponen los aportes de la arqueología en el proceso de gestación y desarrollo del campo técnico y científico judicial que investiga la violencia política y los crímenes de lesa humanidad en la provincia de Tucumán (Argentina) que tuvo lugar entre los años 1975 y 1983. Tal circunstancia —es decir, que la disciplina arqueológica haya sustentado la conformación del ámbito forense local—, se sugiere, imprimió un carácter particular a la práctica forense que investiga este período. Se propone exponer la experiencia tucumana al centrarse en los resultados parciales de dos investigaciones forenses y en las que los aportes de la arqueología fueron claves para dimensionar las características que asumió el exterminio en Tucumán.

The genus Amphichorda has been recently re-erected as an independent linage from Beauveria, circumscribed within Cordycipitaceae. However, its phylogenetic relationships with other members of this family remain obscure. In our on-going efforts to expand the knowledge on the diversity of culturable ascomycetes from the Mediterranean Sea, we isolated several specimens of Amphichorda. Preliminary sequence analyses revealed great phylogenetic distance with accepted Amphichorda species and a close relation to Onychophora coprophila. Onychophora is a monotypic genus of enteroblastic conidiogenous cells, presumably related to Acremonium (Bionectriaceae); while Amphichorda exhibits holoblastic conidiogenesis. Here, we examine representative strains of Amphichorda species to resolve the taxonomy of the genus and the above-mentioned fungi combining morphological, ultrastructure and multi-locus phylogenetic analyses (ITS, LSU, tef1, BenA). The results revealed Amphichorda as a member of the Bionectriaceae, where its asexual morphs represent a transition between enteroblastic and holoblastic conidiogenesis for this group of fungi. We also describe and illustrate Amphichorda littoralis sp. nov., and propose the new combination Amphichorda coprophila. In addition, we stablish key phenotypic features to distinguish Amphichorda species and demonstrate the higher salt tolerance degree of A. littoralis, consistent with its marine origin. This work provides a comprehensive framework for future studies in the genus.

Calcium/aminoacids based MOFs (CaHis, CaPhe, and CaTrp) were synthesized by the hydrothermal method. Then, these materials were applied as a filler in the synthesis of composites in hydrogel state based on the biopolymer matrix of collagen-guar gum (CG). The calcium MOFs materials were characterized by ATR-FTIR and XRD, while the morphology, the degradation profile, crosslinking and swelling degree, proliferation and cell viability of porcine dermis fibroblasts were the characteristics analyzed for the composites in hydrogel state. The results indicated that the incorporation of Ca-MOFs into the CG matrix enhances the physicochemical properties of CG, but without affecting their biocompatibility. In this way, the CG-CaTrp demonstrated to be the material with the best physicochemical and biological properties for potential application in tissue engineering of skin.

Based on the physicochemical properties of metal-organic frameworks (MOFs), and the need of having an anti-inflammatory and antibacterial effect at the same time in a material for wound healing applications, a multicomponent polymer system was synthesized. Zn-based MOFs having different amino acids acting as ligands (L-tryptophan (Trp), L-phenylalanine (Phe), and L-histidine (His)) in their coordination sphere were successfully prepared and validated by FTIR and XRD. Each MOF was incorporated into a semi-interpenetrated polymeric network (semi-IPN) based on collagen (C)-guar gum (GG)-polyurethane (PU), given composite hydrogels as end products. The physicochemical properties of these novel composite hydrogels, their in vitro biocompatibility, and their use as cell carriers were studied. The maximum swelling capacity was shown by CGG-Zn(Trp) while the crosslinking index was higher for CGG-Zn(Phe) and CGG-Zn(His), indicating that the chemical structure of the amino acid of the Zn-based MOF tailors these physicochemical properties. All composite hydrogels were resistant to a hydrolysis degradation process (at pH=5 and 7.4) being not entirely degraded after 14 days and having residual masses above 57%. The incorporation of Zn-based MOFs increased the biocompatibility in terms of metabolic activity and proliferation of porcine fibroblast in contact with the composite hydrogels. The low release capacity of fibroblast encapsulated inside hydrogels evaluated for 10 days indicated the non-efficient capacity of these matrixes as cell carriers, regardless of the structure of the Zn-based MOF. The strong adhesion of porcine fibroblast to the composite hydrogels is related to improving metabolic activity allowing its proliferation, making these multicomponent polymeric systems useful as efficient materials in biomedical applications such as wound dressing and tissue engineering.

Hydrogels have a three-dimensional structure of polymer chains composed of hydrophilic end groups. The aim of this review is to show how polyelectrolytes have emerged as a promising and innovative toolkit for delivering and targeting therapeutic bioactive substances. Also, here the most relevant contributions related to hydrogel systems based on polyelectrolytes are presented, highlighting of these systems their main characteristics for applications in biomedicine.

In this work, we report the synthesis of molybdenum metal-organic frameworks (Mo-MOFs) using 1,3,5-benzenetricarboxylic acid and the amino acids L-phenylalanine, L- tryptophan, and L-histidine as ligands. They were incorporated in hydrogel matrixes comprised of collagen and guar gum to obtain composite hydrogels. The effect of chemical structure of Mo-MOFs on the structure, physicochemical properties and in vitro biocompatibility of hydrogels was studied. These biomaterials showed a super absorbent performance (higher than 2000 ± 169%) and a high degree of reticulation (higher than 75 ± 6%). The microstructure of the composites showed a granular morphology with some porosity. These composites were degraded entirely by hydrolysis at pH 5 and pH 7 at room temperature in time lapses shorter than 15 days. Also, they were biocompatible with porcine dermis fibroblasts not showing cytotoxic effects up to 48 h of incubation allowing its proliferation, and it was observed that the MOF containing L-tryptophan improved notably the biocompatibility of the collagen/guar gum matrix. Finally, the matrixes were tested as vehicles for cell encapsulation and release. The slow-release rates show that fibroblasts tend to remain inside the hydrogel matrixes. Thus, these materials are more suitable for cell scaffolds and tissue engineering applications such as wound healing dressings.

Selenium is a non-metal that shows biological interest since it is responsible for modulating various proteins at the micronutrient level in living beings. In this work, new complexes based on the Se (IV) ion with amino acids such as phenylalanine (Se-F), histidine (Se-H) and tryptophan (Se-T) were hydrothermally synthesized and characterized. These were incorporated into biomatrixes based on semi-interpenetrated polymeric networks (Semi-IPN) of collagen-polyurethane-guar gum (CPGG) by the microemulsion process using a mass ratio of 1 wt.% with respect to collagen. The structural and crystalline characteristics that the selenium-amino acid complexes show a performance in modulating the properties of the biomatrixes under study. The results indicate that the incorporation of the complex decreases the crosslinking of the hydrogel, generating granular surfaces with porosity dependent on the type of amino acid. The CPGG Se-T biomatrix shows a swelling capacity of 10200 ± 1100 higher than the CPGG base matrix; while the CPGG Se-F and CPGG Se-T biomatrixes present slow degradation at both physiological and acidic pH. Interestingly, the matrix that includes the Se-F complex significantly stimulates the metabolic activity of L929 fibroblasts for up to 48 h, stimulating their proliferation. The fibroblasts encapsulated on these novel biomatrixes show recurrent release capacity for up to 7 days, where the structure of the CPGG Se-H biomatrix exhibits greater release from the encapsulated cells. These results demonstrate that these innovative biomatrixes could be used in biomedical applications such as dermal tissue regeneration and cell release for a specific biological fate.

Primary cultures of bovine chromaffin cells are considered a good model to evaluate potential neuroprotective compounds for two major reasons: (i) they share many common features to neurons as they synthesize, store, and release neurotransmitters; they are excitable cells that express voltage-dependent calcium, potassium, and sodium channels; they express different neuronal receptor subtypes; and (ii) they can be easily cultured in high quantities from adult animals; as adult para-neurons, they can be used to reproduce different neurodegenerative-like cytotoxicity models. In this chapter, we describe protocols to mimic calcium overload (veratridine and thapsigargin) and oxidative stress (rotenone plus oligomycin-A and 6-hydroxydopamine) to evaluate potential neuroprotective compounds.

The fungi of the order Onygenales can cause important human infections; however, their taxonomy and worldwide occurrence is still little known. We have studied and identified a representative number of clinical fungi belonging to that order from a reference laboratory in the USA. A total of 22 strains isolated from respiratory tract (40%) and human skin and nails (27.2%) showed a malbranchea-like morphology. Six genera were phenotypically and molecularly identified, i.e. Auxarthron/Malbranchea (68.2%), Arachnomyces (9.1%), Spiromastigoides (9.1%), and Currahmyces (4.5%), and two newly proposed genera (4.5% each). Based on the results of the phylogenetic study, we synonymized Auxarthron with Malbranchea, and erected two new genera: Pseudoarthropsis and Pseudomalbranchea. New species proposed are: Arachnomyces bostrychodes, A. graciliformis, Currahmyces sparsispora, Malbranchea gymnoascoides, M. multiseptata, M. stricta, Pseudoarthropsis crassispora, Pseudomalbranchea gemmata, and Spiromastigoides geomycoides, along with a new combination for Malbranchea gypsea. The echinocandins showed the highest in vitro antifungal activity against the studied isolates, followed by terbinafine and posaconazole; in contrast, amphotericin B, fluconazole, itraconazole and 5-fluorocytosine were less active or lacked in vitro activity against these fungi.

Although the Pleosporaceae is one of the species-richest families in the Pleosporales, research into less-explored substrates can contribute to widening the knowledge of its diversity. In our ongoing survey on culturable Ascomycota from freshwater sediments in Spain, several pleosporacean specimens of taxonomic interest were isolated. Phylogenetic analyses based on five gene markers (ITS, LSU, gapdh, rbp2, and tef1) revealed that these fungi represent so far undescribed lineages, which are proposed as two novel genera in the family, i.e., Neostemphylium typified by Neostemphylium polymorphum sp. nov., and Scleromyces to accommodate Scleromyces submersus sp. nov. Neostemphylium is characterized by the production of phaeodictyospores from apically swollen and darkened conidiogenous cells, the presence of a synanamorph that consists of cylindrical and brown phragmoconidia growing terminally or laterally on hyphae, and by the ability to produce secondary conidia by a microconidiation cycle. Scleromyces is placed phylogenetically distant to any genera in the family and only produces sclerotium-like structures in vitro. The geographic distribution and ecology of N. polymorphum and Sc. submersus were inferred from metabarcoding data using the GlobalFungi database. The results suggest that N. polymorphum is a globally distributed fungus represented by environmental sequences originating primarily from soil samples collected in Australia, Europe, and the USA, whereas Sc. submersus is a less common species that has only been found associated with one environmental sequence from an Australian soil sample. The phylogenetic analyses of the environmental ITS1 and ITS2 sequences revealed at least four dark taxa that might be related to Neostemphylium and Scleromyces. The phylogeny presented here allows us to resolve the taxonomy of the genus Asteromyces as a member of the Pleosporaceae.

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International audience; Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. Previously (Geiser et al. 2013; Phytopathology 103:400-408. 2013), the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani Species Complex (FSSC). Subsequently, this concept was challenged by one research group (Lombard et al. 2015 Studies in Mycology 80: 189-245) who proposed dividing Fusarium into seven genera, including the FSSC as the genus Neocosmospora, with subsequent justification based on claims that the Geiser et al. (2013) concept of Fusarium is polyphyletic (Sandoval-Denis et al. 2018; Persoonia 41:109-129). Here we test this claim, and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species recently described as Neocosmospora were recombined in Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural and practical taxonomic option available.

Artificial thermal shock conducted on 50 soil samples from a semi-arid geographic region (Catamarca and La Rioja provinces) in northern Argentina yielded 34 heat-resistant fungal strains. These strains were assigned to seventeen taxa in ten ascomycete genera: Arthrinium (1), Aspergillus (3), Epicoccum (1), Gilmaniella (1), Hamigera (2), Leiothecium (1), Penicillium (2), Talaromyces (4), Trichocladium (1), and Trichoderma (1). All strains were identified by phenotypic features, with molecular data additionally obtained for eleven strains. Five species are reported for the first time in Argentina.

Las estructuras metal-orgánicas (MOFs) son polímeros de coordinación que se componen por un centro metálico y un ligando orgánico, que pueden diseñarse empleando iones metálicos biocompatibles (Fe+3, Zn+2, Mg+2, Ca+2 y Mo+6) y ligandos orgánicos bioactivos, permitiendo la modulación de la estructura y propiedades a escala nanométrica. El objetivo del presente trabajo es dar a conocer un panorama de los materiales empleados en la liberación de fármacos, enfatizando las ventajas, avances y retos en la liberación de fármacos con MOFs nanoestructurados, así como su mecanismo de liberación, degradación y actividad antimicrobiana.

Chrysosporium-related fungi, the cause of superficial and deep mycoses, are an emerging infectious disease affecting not only reptiles but also immunocompromized humans. However, the information on Nannizziopsis arthrosporioides is extremely scarce. We herein characterized N. arthrosporioides isolated from a Cuban rock iguana (Cyclura nubila). Three skin ulcers were found in a Cuban rock iguana after captivity for 8 years. Microscopic examination revealed hyperplastic, hyperkeratotic, and ulcerative dermatitis coupled with numerous branched, septate fungal hyphae. The fungal culture yielded growth of zonate, felted cottony-powdery colonies with lobate margins on medium. Maximum-likelihood phylogeny tree based on the combined partial actin and partial β-tubulin genes demonstrated that current isolates were mostly close to N. arthrosporioides. Furthermore, antifungal susceptibility test demonstrated that N. arthrosporioides had lowest minimal inhibitory concentration (MIC) values to isavuconazole, efinaconazole, and luliconazole, which may be the potential treatment of choice for N. arthrosporioides infection. The current study describes the first confirmed case of dermatomycosis caused by N. arthrosporioides of a captive reptile in Asia with detailed descriptions of the clinical, histopathological, and mycological features. The current findings provide new information on global distribution and host range of N. arthrosporioides and can raise the concern on the transboundary or emerging disease of N. arthrosporioides in Asian region.

Currently, the control of the properties of collagen based hydrogels represents a promising area of research to develop novel materials for biomedical applications. The crosslinking of the collagen with trifunctional polyurethane (PU) allows a hybrid matrix to be formed by improving the coupling with exogenous polymeric chains to generate innovative semi-interpenetrated network (semi-IPN) hydrogels. The incorporation of polyacrylate (PA) within a hybrid matrix of collagen-PU allows to regulate the structure and physicochemical properties such as polymerization rate, physicochemical crosslinking, thermal stability, storage module and swelling/degradation behavior of the 3D matrices in the hydrogel state, also exhibiting modulation of their in vitro biocompatibility properties. This work contemplates the study of the effect of PA concentration on the physicochemical properties and the in vitro biological response of these novel semi-IPN hydrogels based on collagen-PU-PA. The results indicate that semi-IPN hydrogels that include 20 wt% of PA exhibit improved swelling with respect to the collagen-PU hydrogel, controlling the degradation rate in acidic, alkaline and proteolytic media; showing E. coli inhibition capacity, high hemocompatibility and not altering the metabolism of monocytes and fibroblasts growing on them. Therefore, these novel hydrogels represent biomaterials with potential application in biomedical strategies such as wound healing dressings.

Human infections by pleosporalean fungi (class Dothideomycetes, phylum Ascomycota) are rarely reported. Because their identification is challenging using morphological characterization, several phylogenetic markers must be sequenced for an accurate identification and taxonomical placement of the isolates. Three isolates of clinical origin were phenotypically characterized, but due to the absence of relevant morphological traits, D1-D2 domains of the 28S nrRNA gene (LSU), the internal transcribed spacer region (ITS) of the nrRNA, and fragments of the RNA polymerase II subunit 2 (rpb2) and translation elongation factor 1-alpha (tef1) genes were sequenced to allow a phylogenetic analysis that would solve their phylogenetic placement. That analysis revealed that these isolates did not match any previously known pleosporalean genera, and they are proposed here as the new fungal genus, Gambiomyces. Unfortunately, the isolates remained sterile, which, consequently, made the morphological description of the reproductive structures impossible. Future studies should try to understand the behaviour of this fungus in nature as well as its characteristics as an opportunistic fungal pathogen. Molecular identification is becoming an essential tool for proper identification of Dothideomycetes of clinical origin. Lay Abstract We describe a new pleosporalen pathogenic fungus, Gambiomyces profunda, found in superficial to deep samples from a human patient. Because all strains remained sterile, the fungus was finally identified following a phylogenetic analysis by using four different molecular markers.

The contamination of water by Pb2+ ions is a problem that requires an imminent solution. Design of hydrogels based on polymers as well as inorganic phases is an innovative alternative for the generation of matrices with adapted properties. This work proposes the synthesis of a novel composite hydrogel based on collagen-polyurethane-chitosan reinforced with manganite; this inorganic phase increases the velocity of the adsorption process of the Pb2+ ions. The effect of the concentration of manganite on the properties of composite hydrogels is studied. The results indicate that the composite reinforced with manganite presents an amorphous structure, improved mechanical properties and resistance to the both acidic and proteolytic degradation. The hydrogel with 35 wt% of manganite show a removal rate of Pb2+ of 91 ± 6% at 24 h. These hydrogel composites could represent an efficient and sustainable alternative for the removal of Pb2+ ions from contaminated water.

Coprophilous fungi are saprotrophic organisms that show great diversity, mainly on herbivore dung. The physico-chemical characteristics of this peculiar substrate combined with the high level of fungal adaptation to different environmental conditions offer the perfect setting for discovering new taxa. This study focused on the species diversity of penicillium-like fungi isolated mainly from herbivore dung collected at different Spanish locations. From 130 samples, a total of 104 isolates were obtained, and 48 species were identified. Preliminary identifications were based on morphology and partial β-tubulin (tub2) gene sequences. Putative new taxa were characterized by a multi-gene sequencing analysis testing the tub2, the internal transcribed spacer rDNA (ITS), calmodulin (cmdA), and RNA polymerase II second largest subunit (rpb2) genes, and a detailed phenotypic study. Using this polyphasic approach and following the genealogical concordance phylogenetic species recognition (GCPSR) method, we propose the new genera Penicillago (for Penicillium nodositatum) and Pseudopenicillium (for Penicillium megasporum and P. giganteum) in the family Aspergillaceae, and 11 new species, including seven Penicillium, three Talaromyces and one Pseudopenicillium. A lectotype and epitype are designed for Penicillium nodositatum. Our results show that the species diversity of penicillium-like fungi on herbivore dung has not been widely studied and that this substrate seems to be a good reservoir of interesting Eurotialean fungi.

Scedosporium spp. are the second most prevalent filamentous fungi after Aspergillus spp. recovered from cystic fibrosis (CF) patients in various regions of the world. Although invasive infection is uncommon prior to lung transplantation, fungal colonization may be a risk factor for invasive disease with attendant high mortality post-transplantation. Abundant in the environment, Scedosporium aurantiacum has emerged as an important fungal pathogen in a range of clinical settings. To investigate the population genetic structure of S. aurantiacum, a MultiLocus Sequence Typing (MLST) scheme was developed, screening 24 genetic loci for polymorphisms on a tester strain set. The six most polymorphic loci were selected to form the S. aurantiacum MLST scheme: actin (ACT), calmodulin (CAL), elongation factor-1α (EF1α), RNA polymerase subunit II (RPB2), manganese superoxide dismutase (SOD2), and β-tubulin (TUB). Among 188 global clinical, veterinary, and environmental strains, 5 to 18 variable sites per locus were revealed, resulting in 8 to 23 alleles per locus. MLST analysis observed a markedly high genetic diversity, reflected by 159 unique sequence types. Network analysis revealed a separation between Australian and non-Australian strains. Phylogenetic analysis showed two major clusters, indicating correlation with geographic origin. Linkage disequilibrium analysis revealed evidence of recombination. There was no clustering according to the source of the strains: clinical, veterinary, or environmental. The high diversity, especially amongst the Australian strains, suggests that S. aurantiacum may have originated within the Australian continent and was subsequently dispersed to other regions, as shown by the close phylogenetic relationships between some of the Australian sequence types and those found in other parts of the world. The MLST data are accessible at http://mlst.mycologylab.org. This is a joined publication of the ISHAM/ECMM working groups on “Scedosporium/Pseudallescheria Infections” and “Fungal Respiratory Infections in Cystic Fibrosis”.

La contaminación por metales pesados es un problema, que hoy en día no se ha logrado disminuir. Por esta razón, es necesario innovar constantemente las técnicas tradicionales con el fin de aplicar procesos eficientes que ayuden a remover los contaminantes e incluso recuperarlos para ser reincorporados a procesos productivos. En este contexto, la adsorción es una técnica tan versátil, que es viable su aplicación con materiales de diferentes características. Entre los materiales que han resultado adsorbentes eficientes, se encuentran las partículas inorgánicas y los polímeros/biopolímeros. Estos componentes por si solos presentan capacidades adsorbentes aceptables, pero en los últimos años se ha explorado la generación de matrices poliméricas en estado hidrogel reforzadas con materiales inorgánicos o mezclas de redes poliméricas generando compósitos, para mejorar o incrementar la capacidad de adsorción. Los hidrogeles compósitos conjugan una adsorción eficaz, buena área superficial específica y de fácil aplicabilidad, por lo que representan una gran alternativa para la disminución de los iones de metales pesados presentes en los ecosistemas acuáticos. Por este motivo, es la presente revisión de los materiales con propiedades adsorbentes, las estrategias para generar compósitos en estado hidrogel y sus propiedades adaptadas para la adsorción de iones de metales pesados, así como los retos y las áreas de oportunidad implícitos en esta generación de materiales innovadores.