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¿Tienen GPT-3.5 y GPT-4 un estilo de escritura diferente del estilo humano? : un estudio exploratorio para el español
(RAEL : Revista Electrónica de Lingüística Aplicada, 2024) Alonso Simón, Lara; Fernández-Pampillón Cesteros, Ana María; Fernández Trinidad, Marianela; Márquez Cruz, Manuel
RESUMEN: La cuestión que se aborda en este trabajo de investigación es la comprobación, mediante técnicas estadísticas, de que los modelos generativos de lenguaje GPT-3.5 (versión gratuita) y GPT-4 (versión de pago) de ChatGPT tienen un estilo de escritura distinto al de los humanos, y que pueden diferenciarse, al menos, por tres tipos de rasgos: léxicos, signos de puntuación y estructura sintáctica de las oraciones. Determinar si los grandes modelos de lenguaje tienen un estilo propio es relevante de cara a poder detectar la autoría automática de los textos. En trabajos anteriores se construyó un corpus comparable de textos humanos y automáticos en español y, mediante un estudio cualitativo, se localizó un conjunto de rasgos lingüísticos y estilísticos propios de cada autor. En este trabajo se ha podido comprobar cuantitativamente que 17 variables lingüísticas presentan diferencias estadísticamente significativas entre autores humanos y los modelos GPT-3.5 y GPT-4.
Toxicity at the edge of life: a review on cyanobacterial toxins from extreme environments
(Marine Drugs, 2017) Cirés, Samuel; Casero, María Cristina; Quesada, Antonio
Cyanotoxins are secondary metabolites produced by cyanobacteria, of varied chemical nature and toxic effects. Although cyanobacteria thrive in all kinds of ecosystems on Earth even under very harsh conditions, current knowledge on cyanotoxin distribution is almost restricted to freshwaters from temperate latitudes. In this review, we bring to the forefront the presence of cyanotoxins in extreme environments. Cyanotoxins have been reported especially in polar deserts (both from the Arctic and Antarctica) and alkaline lakes, but also in hot deserts, hypersaline environments, and hot springs. Cyanotoxins detected in these ecosystems include neurotoxins—anatoxin-a, anatoxin-a (S), paralytic shellfish toxins, β-methylaminopropionic acid, N-(2-aminoethyl) glycine and 2,4-diaminobutyric acid- and hepatotoxins –cylindrospermopsins, microcystins and nodularins—with microcystins being the most frequently reported. Toxin production there has been linked to at least eleven cyanobacterial genera yet only three of these (Arthrospira, Synechococcus and Oscillatoria) have been confirmed as producers in culture. Beyond a comprehensive analysis of cyanotoxin presence in each of the extreme environments, this review also identifies the main knowledge gaps to overcome (e.g., scarcity of isolates and –omics data, among others) toward an initial assessment of ecological and human health risks in these amazing ecosystems developing at the very edge of life.
Humor Styles in Healthcare Professionals: a Correlational Study
(Holistic Nursing Practice, 2024) Leñero Cirujano, Miriam; Moro-Tejedor, Mª Nieves; Torres González, Juan Ignacio; González Ordi, Héctor; Gómez Higuera, Jacinto
Using humor as a caregiving strategy can help professionals perceive daily and work-related events from a more optimistic and light-hearted perspective. The main objective of this study was to analyze humor styles among health care professionals. A cross-sectional and correlational design was employed. Data were collected using the Humor Styles Questionnaire, which measures four humor styles: affiliative, self-enhancing, aggressive, and self-defeating humor. Health care professionals scored higher in positive humor than negative humor. Age exhibited a negative correlation with positive humor. Significant differences were observed between marital status and affiliative and self-enhancing humor, professional category and hospital unit with aggressive humor, shift work and self-enhancing humor, and type of contract and experience with affiliative humor. Health care professionals employ various humor styles based on their social and work contexts. It is crucial for health care professionals to receive training in the use of positive humor to consciously avoid humor styles that can hinder well-being.
Paclitaxel-Loaded Folate-Targeted Albumin-Alginate Nanoparticles Crosslinked with Ethylenediamine. Synthesis and In Vitro Characterization
(Polymers, 2021) Martínez Relimpio, Ana María; Benito, Marta; Pérez Izquierdo, Elena; Teijón López, César; Olmo López, Rosa María; Blanco Gaitán, María Dolores
Among the different ways to reduce the secondary effects of antineoplastic drugs in cancer treatment, the use of nanoparticles has demonstrated good results due to the protection of the drug and the possibility of releasing compounds to a specific therapeutic target. The α-isoform of the folate receptor (FR) is overexpressed on a significant number of human cancers; therefore, folate-targeted crosslinked nanoparticles based on BSA and alginate mixtures and loaded with paclitaxel (PTX) have been prepared to maximize the proven antineoplastic activity of the drug against solid tumors. Nanometric-range-sized particles (169 ± 28 nm–296 ± 57 nm), with negative Z-potential values (between −0.12 ± 0.04 and −94.1± 0.4), were synthesized, and the loaded PTX (2.63 ± 0.19–3.56 ±0.13 µg PTX/mg Np) was sustainably released for 23 and 27 h. Three cell lines (MCF-7, MDA-MB-231 and HeLa) were selected to test the efficacy of the folate-targeted PTX-loaded BSA/ALG nanocarriers. The presence of FR on the cell membrane led to a significantly larger uptake of BSA/ALG–Fol nanoparticles compared with the equivalent nanoparticles without folic acid on their surface. The cell viability results demonstrated a cytocompatibility of unloaded nanoparticle– Fol and a gradual decrease in cell viability after treatment with PTX-loaded nanoparticle–Fol due to the sustainable PTX release.
Gypsum gardens: self-assembled tubular structures of calcium sulfate with relevance for the detection of extraterrestrial Life
(Angewandte Chemie International Edition, 2025) Reigl, Selina; Wagner, Elisabeth; Pimentel Guerra, Carlos; Kunz, Werner; Van Driessche, Alexander E. S.; Kellermeier, Matthias
Form is a common and intuitive criterion to distinguish between the realm of living species and the inanimate nature. However, there are in fact no strict boundaries in terms of morphology, as exemplified by so-called chemical gardens, which form by self-assembly in purely inorganic systems and yet closely mimic the appearance of trees and other plants. While such structures have been reported for a broad range of compositions–most notably silicates of various types of metal cations as well as prominent (bio)minerals like calcium carbonate or phosphate–one important material has been missing in the comprehensive list of these chemobrionic systems: calcium sulfate. In the present work, we succeeded in preparing well-developed CaSO4-based chemical gardens by addition of a concentrated solution of sodium sulfate to solid crystals of calcium chloride. The formed structures were characterized in detail with respect to their growth behavior, mineralogy, and texture. We find hollow tubular architectures consisting of oriented gypsum crystals and delineating smooth curvatures with multiple branching sites. Beyond the sheer beauty of these self-assembled mineral structures, the results of our study bear deep implications for the detection and interpretation of potential past life on Mars, where abundant deposits of calcium sulfate exist. In addition, the current picture of geochemical environments on the early red planet is fully consistent with the experimental conditions used in the present work, rendering the formation and presence of chemical gardens on Mars plausible.
Fundamental drivers for endolithic microbial community assemblies in the hyperarid Atacama Desert
(Environmental Microbiology, 2018) Meslier, Victoria; Casero, María Cristina; Dailey, Micah; Wierzchos, Jacek; Ascaso, Carmen; Artieda, Octavio; McCullough, Peter; DiRuggiero, Jocelyne
In hyperarid deserts, endolithic microbial communities colonize the rocks’ interior as a survival strategy. Yet, the composition of these communities and the drivers promoting their assembly are still poorly understood. We analysed the diversity and community composition of endoliths from four different lithic substrates – calcite, gypsum, ignimbrite and granite – collected in the hyperarid zone of the Atacama Desert, Chile. By combining microscopy, mineralogy, spectroscopy and high throughput sequencing, we found these communities to be highly specific to their lithic substrate, although they were all dominated by the same four main phyla, Cyanobacteria, Actinobacteria, Chloroflexi and Proteobacteria. Our finding indicates a fine scale diversification of the microbial reservoir driven by substrate properties. The data suggest that the overall rock chemistry and the light transmission properties of the substrates are not essential drivers of community structure and composition. Instead, we propose that the architecture of the rock, i.e., the space available for colonization and its physical structure, linked to water retention capabilities, is ultimately the driver of community diversity and composition at the dry limit of life.
Nanogeochemistry of Ni, Co, and Cu in zoned marcasite-pyrite crystals
(American Mineralogist, 2025) Ferreira García, Amira Rosa; González Jiménez , José María; Yesares Ortiz, María Dolores; Blanco Quintero, Idael Francisco; Piña García, Rubén; Gervilla, Fernando
This study describes the incorporation mechanism of Ni, Co, and Cu in zoned marcasite-pyrite (FeS2) crystals from vein-type hydrothermal mineralization in the Sierra de Orihuela (Betic Cordillera, SE Spain). Single-spot analyses and X-ray mapping by electron probe microanalyzer (EPMA) of zoned marcasite-pyrite grains reveal positive correlations among Ni (up to 12.8 wt%), Co (up to 4.42 wt%), and Cu (up to 7.33 wt%), as well as a negative correlation between these elements and Fe. In contrast, nanoscale analysis using high-resolution transmission electron microscopy (HRTEM) reveals that these compositional variations arise from a combination of solid solutions and mineral nanoparticles of Ni, Co, and Cu. The cores of the zoned grains are marcasite, which is depleted in Ni, Co, Cu, and other trace metals. Cores are surrounded by zoned rims that contain inner portions with nanoscale zoning defined by alternating layers (∼500 nm thickness) of pyrite (FeS2) with cattierite (CoS2) and/or carrollite (CuCo2S4). This transitions to outer portions exhibiting Pa3 pyrite with frequent discrete mineral nanoparticles, including 80–120 nm sized cubic carrollite (CuCo2S4), tetragonal, chalcopyrite (CuFeS2), and cubic, violarite (FeNi2S4). The shift in the mode of Ni, Co, and Cu occurrence, from incorporation via solid solution to nanoparticles, reflects variations in the physicochemical conditions of the crystallizing system rather than the specific nature of the crystalline mineral matrix forming the zoned structure. The formation of the zoned structure begins with the initial crystallization of trace-element-poor cores of marcasite. This is followed by pyrite rims displaying an outward progressive enlargement of the crystal lattice due to the incorporation of Ni, Co, and Cu in solid solution, reaching characteristic d-spacings of carrollite and cattierite. Finally, direct precipitation of pyrite and Ni-Co-Cu-rich nanoparticles occurs when pH increases and salinity decreases. Nanoscale insights from Sierra de Orihuela mineralization provide an unprecedented view of the partitioning of Ni, Co, and Cu into Fe-sulfides. These findings reveal mechanisms of metal enrichment in hydrothermal systems that are invisible to conventional tools used in the study of mineral deposits.
Molecular detection of extended spectrum β-lactamase genes in Escherichia coli clinical isolates from diarrhoeic children in Kano, Nigeria
(Plos One, 2020) Saka, Habeeb Kayode; García-Soto, Silvia; Dabo, Nasir Tukur; López Chavarrías, Vicente; Muhammad, Bashir; Ugarte Ruiz, María; Álvarez Sánchez, Julio
The increase in antimicrobial resistance in developed and developing countries is a global public health challenge. In this context β-lactamase production is a major contributing factor to resistance globally. The aim of this study was to determine the prevalence of phenotypic and genotypic extended spectrum β-lactamases (ESBLs) in 296 E. coli isolates recovered from diarrhoeic children younger than five years in Kano whose susceptibility profile against 7 antimicrobials had been determined. The E. coli isolates were subjected to double disc synergy test for phenotypic ESBLs detection and ESBL associated genes (blaCTX-M, blaTEM and blaSHV) were detected using conventional PCR. Phenotypically, 12.8% (38/296) E. coli isolates presented a ESBLs phenotype, with a significantly higher proportion in isolates from females compared with males (P-value = 0.024). blaCTX-M 73.3% and blaTEM 73.3% were the predominant resistance genes in the ESBLs positive E. coli (each detected in 22/30 isolates, of which 14 harboured both). In addition, 1/30 harboured blaCTX-M + blaTEM + blaSHV genes simultaneously. This study demonstrates the presence of ESBLs E. coli isolates in clinically affected children in Kano, and demonstrates the circulation of blaCTX-M and blaTEM associated with those phenotypes. Enactment of laws on prudent antibiotic use is urgently needed in Kano
Generation and NGS profiling of naïve rabbit antibody libraries for efficient monoclonal antibody selection
(New Biotechnology, 2026) Rodríguez Gómez, Santiago; García García, Aina; Martín De Santos, María Del Rosario; García Lacarra, Teresa
Rabbit monoclonal antibodies (mAbs) are highly valued for their exceptional affinity and specificity, yet naïve rabbit antibody libraries generated by phage display remain rarely described, limiting the in vitro exploitation of the unique rabbit immune repertoire. To address this gap, we constructed two naïve scFv phage display libraries—one incorporating κ and the other λ light chains—assembled from bone marrow, spleen, and peripheral blood of rabbits from two breeds. Together, they yielded a combined theoretical diversity of 7 × 10⁹ independent clones, with the λ library providing access to a rarely explored component of the rabbit repertoire. Next-generation sequencing (NGS) confirmed the high genetic diversity of the libraries and allowed exploration of antibody repertoire regions in rabbits that have been scarcely characterized. A diverse panel of scFvs specific to two major sesame allergens (11S globulins and 2S albumins) have been isolated from both libraries as a proof of concept of their functionality. Selected scFvs were successfully reformatted into full-length rabbit IgG retaining target specificity and expressed in CHO cells at high expression yields. Overall, the constructed libraries provide a robust and versatile resource for antibody discovery, enabling the development of high-quality rabbit mAbs for applications in diagnostics, food safety, and broader analytical applications.
The Bilinear Bochner-Riesz Operator at the Critical Index
(Potential Analysis, 2026) Carro Rossell, María Jesús; Luque Martínez, Teresa Elvira; Sánchez Pascuala Dones, Laura
We study boundedness properties for the bilinear Bochner-Riesz operator at the critical index. Starting from the weighted estimate previously established by Jotsaroop, Shrivastava, and Shuin, we develop a technique that combines quantitative bilinear Rubio de Francia extrapolation with a suitable bilinear version of Yano’s extrapolation theorem. This method yields a range of new weighted endpoint estimates. Our results cover all open endpoints and include both one-weight and two-weight inequalities.
Stream channel morphology and water flow in ice-free areas of Byers Peninsula, South Shetland Islands, Antarctica
(Geomorphology, 2026) Ortega Becerril, José Antonio; Schmid, Thomas; Corella, Juan Pablo; Carcavilla Urquí, Luis; Calle Navarro, Mikel; López Martínez, Jerónimo
Fluvial stream channels in Antarctic ice-free areas provide valuable insights into deglaciation/neoglaciation, and the pace of morphogenetic processes shaping the landscape. The northern Antarctic Peninsula, particularly the South Shetland Islands, offers unique conditions for such studies due to extensive ice-free zones, glacial history, and rapidly changing environments. This research focuses on Byers Peninsula (BP), the largest ice-free area of the archipelago, characterized by a well-developed drainage system previously studied and mapped. This paper expands knowledge of channel development, water flow, and related morphologies, relevant for understanding other ice-free Antarctic regions. Morphometric analyses were conducted on 26 streams, alongside evaluation of channel equilibrium in three selected watersheds. Water flow was monitored for two years in two streams using data loggers, with complementary field data from a third. Seven morphotypes were distinguished within a theoretical watershed, including diffuse drainage, platform lakes, braided systems, canyons, cutting raised platforms, open braided channels, entrenched channels on raised beaches, lagoons and/or small fans. Results highlight significant variability in channel size and hydraulic properties across sub-basins. Southern BP streams reveal higher fluvial energy, while Western streams, draining larger basins with higher stream orders, display more advanced fluvial development and concentrate the main systems of the region. Basin orientation, glacier proximity, and topography emerged as key factors shaping channel dimensions, while glacial lake outburst floods strongly influenced morphology and sediment dynamics. The presence of paired morphometrically similar channels on North and South coasts supports a stepwise west–east retreat of Rotch Dome Glacier, marked by stagnation phases producing mature channels and rapid retreats yielding less developed systems.
Técnicas geoeléctricas para la detección y monitorización de filtraciones en embalses
(Ingeopres, 2004) Martínez-Pagán, Pedro; Aracil Ávila, Enrique; Faz, Ángel
En este artículo se describe brevemente una serie de técnicas geoeléctricas que han resultado positivas en la detección de filtraciones o fugas de agua a través del revestimiento de embalses, pantanos u otro tipo de estructuras hidráulicas de almacenamiento, con el fin de darlas a conocer entre el colectivo de profesionales que, de alguna forma, estén implicados con las obras hidráulicas (Administración, gestores, ingenieros, constructores, etc.). La información que proporcionan estas técnicas es muy adecuada tanto para conocer el estado del revestimiento frente a posibles roturas, cortes accidentales o perforaciones, como para determinar a tiempo la ubicación de una fuga y poder llevar a cabo la actuación correspondiente mitigando de esta manera el peligro que podría correr la integridad de la estructura hidráulica y evitando la pérdida del agua y sus graves efectos en el entorno.
Human-wildlife ecological interactions shape Escherichia coli population and resistome in two sloth species from Costa Rica
(Antimicrobials and resistance, 2025) Calvo-Fernandez, Cristina; Dolcet-Negre, Marta M.; Martin-Maldonado, Barbara; Pulido-Vadillo, Mario; Montero Serra, Natalia; Such, Roger; García-Vila, Encarnación; Delgado Blas, José Francisco; González Zorn, Bruno
Antimicrobial resistance (AMR) is a global health concern, with natural ecosystems acting as reservoirs for resistant bacteria. We assessed AMR in Escherichia coli isolated from two wild sloth species in Costa Rica. E. coli from two-toed sloths (Choloepus hoffmanni), a species with greater mobility and a broader diet, showed resistance to sulfamethoxazole (25%), tetracycline (9.4%), chloramphenicol (6.3%), ampicillin (6.3%), trimethoprim (3.1%), and ciprofloxacin (3.1%), which correlated with the presence of resistance genes (tet(A), tet(B), blaTEM-1B, aph(3")-Id, aph(6)-Id, sul2, qnrS1, floR and dfrA8). E. coli from three-toed sloths (Bradypus variegatus) showed 40% resistance to sulfamethoxazole despite no detected resistance genes, suggesting a regional effect. A significant negative correlation was found between AMR and distance to human-populated areas, highlighting anthropogenic impact on AMR spread. Notably, E. coli isolates from remote areas with no human impact indicate that some ecosystems remain unaffected. Preserving these areas is essential to protect environmental and public health
Comparing serotyping with whole-genome sequencing for subtyping of non-typhoidal Salmonella enterica: a large-scale analysis of 37 serotypes with a public health impact in the USA
(Microbiology Society, 2020) Elnekave, Ehud; Hong, Samuel L.; Lim, Seunghyun; Johnson, Timothy J.; Perez, Andres; Álvarez Sánchez, Julio
Serotyping has traditionally been used for subtyping of non-typhoidal Salmonella (NTS) isolates. However, its discriminatory power is limited, which impairs its use for epidemiological investigations of source attribution. Whole-genome sequencing (WGS) analysis allows more accurate subtyping of strains. However, because of the relative newness and cost of routine WGS, large-scale studies involving NTS WGS are still rare. We aimed to revisit the big picture of subtyping NTS with a public health impact by using traditional serotyping (i.e. reaction between antisera and surface antigens) and comparing the results with those obtained using WGS. For this purpose, we analysed 18 282 sequences of isolates belonging to 37 serotypes with a public health impact that were recovered in the USA between 2006 and 2017 from multiple sources, and were available at the National Center for Biotechnology Information (NCBI). Phylogenetic trees were reconstructed for each serotype using the core genome for the identification of genetic subpopulations. We demonstrated that WGS-based subtyping allows better identification of sources potentially linked with human infection and emerging subpopulations, along with providing information on the risk of dissemination of plasmids and acquired antimicrobial resistance genes (AARGs). In addition, by reconstructing a phylogenetic tree with representative isolates from all serotypes (n=370), we demonstrated genetic variability within and between serotypes, which formed monophyletic, polyphyletic and paraphyletic clades. Moreover, we found (in the entire data set) an increased detection rate for AARGs linked to key antimicrobials (such as quinolones and extended-spectrum cephalosporins) over time. The outputs of this large-scale analysis reveal new insights into the genetic diversity within and between serotypes; the polyphyly and paraphyly of certain serotypes may suggest that the subtyping of NTS to serotypes may not be sufficient. Moreover, the results and the methods presented here, leading to differentiation between genetic subpopulations based on their potential risk to public health, as well as narrowing down the possible sources of these infections, may be used as a baseline for subtyping of future NTS infections and help efforts to mitigate and prevent infections in the USA and globally
Global Distribution of Extended Spectrum Cephalosporin and Carbapenem Resistance and Associated Resistance Markers in Escherichia coli of Swine Origin – A Systematic Review and Meta-Analysis
(Frontiers in Microbiology, 2022) Hayer, Shivdeep Singh; Casanova-Higes, Alejandro; Paladino, Eliana; Elnekave, Ehud; Nault, Andre; Johnson, Timothy; Bender, Jeff; Perez, Andres; Álvarez Sánchez, Julio
Third generation cephalosporins and carbapenems are considered critically important antimicrobials in human medicine. Food animals such as swine can act as reservoirs of antimicrobial resistance (AMR) genes/bacteria resistant to these antimicrobial classes, and potential dissemination of AMR genes or resistant bacteria from pigs to humans is an ongoing public health threat. The objectives of this systematic review and meta-analysis were to: (1) estimate global proportion and animal-level prevalence of swine E. coli phenotypically resistant to third generation cephalosporins (3GCs) and carbapenems at a country level; and (2) measure abundances and global distribution of the genetic mechanisms that confer resistance to these antimicrobial classes in these E. coli isolates. Articles from four databases (CAB Abstracts, PubMed/MEDLINE, PubAg, and Web of Science) were screened to extract relevant data. Overall, proportion of E. coli resistant to 3GCs was lower in Australia, Europe, and North America compared to Asian countries. Globally, <5% of all E. coli were carbapenem-resistant. Fecal carriage rates (animal-level prevalence) were consistently manifold higher as compared to pooled proportion of resistance in E. coli isolates. blaCTX–M were the most common 3GC resistance genes globally, with the exception of North America where blaCMY were the predominant 3GC resistance genes. There was not a single dominant blaCTX–M gene subtype globally and several blaCTX–M subtypes were dominant depending on the continent. A wide variety of carbapenem-resistance genes (blaNDM–, VIM–, IMP–, OXA–48, and KPC–) were identified to be circulating in pig populations globally, albeit at very-low frequencies. However, great statistical heterogeneity and a critical lack of metadata hinders the true estimation of prevalence of phenotypic and genotypic resistance to these antimicrobials. Comparatively frequent occurrence of 3GC resistance and emergence of carbapenem resistance in certain countries underline the urgent need for improved AMR surveillance in swine production systems in these countries
Dissemination Routes of Carbapenem and Pan-Aminoglycoside Resistance Mechanisms in Hospital and Urban Wastewater Canalizations of Ghana
(mSystems, 2022) Delgado Blas, José Francisco; Valenzuela Agüi, Cecilia; Marin Rodriguez, Elena; Serna Bernaldo, Carlos; Montero Serra, Natalia; Saba, Courage Kosi Setsoafia; González Zorn, Bruno
Wastewater has a major role in antimicrobial resistance (AMR) dynamics and public health. The impact on AMR of wastewater flux at the community-hospital interface in low- and middle-income countries (LMICs) is poorly understood. Therefore, the present study analyzed the epidemiological scenario of resistance genes, mobile genetic elements (MGEs), and bacterial populations in wastewater around the Tamale metropolitan area (Ghana). Wastewater samples were collected from the drainage and canalizations before and after three hospitals and one urban waste treatment plant (UWTP). From all carbapenem/pan-aminoglycoside-resistant bacteria, 36 isolates were selected to determine bacterial species and phenotypical resistance profiles. Nanopore sequencing was used to screen resistance genes and plasmids, whereas, sequence types, resistome and plasmidome contents, pan-genome structures, and resistance gene variants were analyzed with Illumina sequencing. The combination of these sequencing data allowed for the resolution of the resistance gene-carrying platforms. Hospitals and the UWTP collected genetic and bacterial elements from community wastewater and amplified successful resistance gene-bacterium associations, which reached the community canalizations. Uncommon carbapenemase/β-lactamase gene variants, like blaDIM-1, and novel variants, including blaVIM-71, blaCARB-53, and blaCMY-172, were identified and seem to spread via clonal expansion of environmental Pseudomonas spp. However, blaNDM-1, blaCTX-M-15, and armA genes, among others, were associated with MGEs that allowed for their dissemination between environmental and clinical bacterial hosts. In conclusion, untreated hospital wastewater in Ghana is a hot spot for the emergence and spread of genes and gene-plasmid-bacterium associations that accelerate AMR, including to last-resort antibiotics. Urgent actions must be taken in wastewater management in LMICs in order to delay AMR expansion. IMPORTANCE Antimicrobial resistance (AMR) is one the major threats to public health today, especially resistance to last-resort compounds for the treatment of critical infections, such as carbapenems and aminoglycosides. Innumerable works have focused on the clinical ambit of AMR, but studies addressing the impact of wastewater cycles on the emergence and dissemination of resistant bacteria are still limited. The lack of knowledge is even greater when referring to low- and middle-income countries, where there is an absence of accurate sanitary systems. Furthermore, the combination of short- and long-read sequencing has surpassed former technical limitations, allowing the complete characterization of resistance genes, mobile genetic platforms, plasmids, and bacteria. The present study deciphered the multiple elements and routes involved in AMR dynamics in wastewater canalizations and, therefore, in the local population of Tamale, providing the basis to adopt accurate control measures to preserve and promote public health
Addressing challenges in wildlife rehabilitation: antimicrobial-resistant patterns in Staphylococcus spp. from wounds and fractures in wild birds
(Animals, 2024) Sánchez Ortiz, Esther; Blanco Gutiérrez, María Del Mar; Calvo Fernández, Cristina; Mencía Gutiérrez, Aida; Pastor Tiburón, Natalia; Alvarado Piqueras, Alberto; Pablos Tanarro, Alba; Martín Maldonado, Bárbara
Injuries and bone fractures are the most frequent causes of admission at wildlife rescue centers. Wild birds are more susceptible to open fractures due to their anatomical structure, which can lead to osteomyelitis and necrosis. Antibiotic therapy in these cases is indispensable, but the increase of antimicrobial-resistant isolates in wildlife has become a significant concern in recent years. In this context, the likelihood of antibiotic failure and death of animals with infectious issues is high. This study aimed to isolate, identify, and assess the antimicrobial resistance pattern of bacteria in wounds and open fractures in wild birds. To this end, injured birds admitted to a wildlife rescue center were sampled, and bacterial isolation and identification were performed. Then, antimicrobial susceptibility testing was assessed according to the disk diffusion method. In total, 36 isolates were obtained from 26 different birds. The genera detected were Staphylococcus spp. (63.8%), Escherichia (13.9%), Bacillus (11.1%), Streptococcus (8.3%), and Micrococcus (2.8%). Among Staphylococcus isolates, S. lentus and S. aureus were the most frequent species. Antimicrobial resistance was detected in 82.6% of the isolates, among which clindamycin resistance stood out, and 31.6% of resistant isolates were considered multidrug-resistant. Results from this study highlight the escalating scope of antimicrobial resistance in wildlife. This level of resistance poses a dual concern for wildlife: firstly, the risk of therapeutic failure in species of significant environmental value, and, secondly, the circulation of resistant bacteria in ecosystems.
The enigmatic ailurid Magerictis imperialensis (Mammalia: Carnivora) unveiled: a systematic approach to the early Ailuridae
(Journal of Systematic Palaeontology, 2025) Morales,Jorge; Abella,Juan; Caballero, Oscar; De Miguel, Daniel; Peláez- Campomanes, Pablo; Valenciano Vaquero, Alberto
We present a detailed description of the craniodental and postcranial remains of the enigmatic Magerictis imperialensis, a basal Ailuridae previously known only from a single m2 from the Middle Miocene of the Madrid Basin (Spain). The discovery of new specimens from eight Middle Miocene (MN5–MN6) localities in Madrid has yielded comprehensive information on the dentition, mandibular morphology, and postcranial skeleton of this species. These new fossils provide an excellent opportunity to revise the phylogenetic relationships of Magerictis and related musteloids from the Oligocene and Miocene of Eurasia and North America. Our phylogenetic analysis indicates that Magerictis and Rothictis gen. nov. are the most basal members of the Aiuluridae. Both genera, together with Alopecocyon, Actiocyon, and Protursus, underwent a limited adaptive radiation during the Middle and Late Miocene in Eurasia and North America. This radiation potentially includes the ancestors of the most specialized ailurids (Simocyon, and the ailurines Parailurus, Pristinailurus and Ailurus). The postcranial elements attributed to Magerictis, particularly the astragalus and calcaneus, exhibit a morphological pattern comparable to that of Ailurus, thereby distinguishing it from other Musteloidea. A systematic rearrangement of the primitive Holartic musteloids from the Oligocene and Miocene is proposed. The Ailuridae are divided into three subfamilies: (i) Ailurinae for Ailurus, Parailurus and Pristinailurus; (ii) Simocyoninae, which includes Simocyon, Protursus, Alopecocyon and Actiocyon; and (iii) Magerictinae nov. rank for Magerictis and Rothictis gen. nov. (type species Rothictis wintershofensis comb. nov.). The family Amphictidae Winge, Citation1895 is revalidated for Amphictis and Bonisictis gen. nov. (type species Bonisictis ambiguus comb. nov.).
In field study on immune-genes expression during an outbreak of rainbow trout (Onchorhynchus mykiss) lactococcosis
(Aquaculture, 2023) Khalil, Sarker Mohammed Ibrahim; Saccà, Elena; Galeotti, Marco; Sciuto, Simona; Stoppani, Nadia; Acutis, Pier Luigi; Öztürk, Rafet Cagri; Bitchava, Konstantina; Blanco Gutiérrez, María Del Mar; Fariano, Lucio; Prearo, Marino; Colussi, Silvia; Volpatti, Donatella
Italian rainbow trout (Oncorhynchus mykiss) farms are periodically affected by outbreaks of lactococcosis caused by Lactococcus garvieae, and rearing basins reveal simultaneously asymptomatic and symptomatic fish. The present study, as part of an “in field” sanitary survey, was designed to describe the expression of immune related genes in infected versus healthy fish, as well as to explore a Near Infrared Spectroscopy (NIR) as a novel approach to discriminate between them. Measurements/sampling were performed in a farm of Northern Italy and included two groups of fish (150–300 g), sharing the same basin: asymptomatic (n = 10) and symptomatic (n = 9). Fingerling (n = 5, 15 g) were also sampled from the farm internal hatchery and considered as L. garvieae-free reference group. NIR spectra were collected from the abdominal region of the fish through the SCiO molecular device. Spleen and head kidney were sampled for bacterial detection (PCR). Head kidney was also subjected to gene expression analysis (qPCR). Seven out of nine (7/9) symptomatic trout were L.garvieae positive (bacterial DNA) while all the asymptomatic (10/10) and fingerling (2/2) were L. garvieae negative. SCiO scanning provided two different spectral populations, almost coinciding with the two fish groups considered (asymptomatic and symptomatic). Among cytokines, IL-1β showed significant up-regulation in symptomatic group compared to asymptomatic group (P < 0.05) while IL-8 showed very high (P < 0.01) and high significant (P < 0.05) differences in its up-regulation in symptomatic group compared to asymptomatic group and fingerling, respectively. IL-10 showed a tendency of significant over-expressed in symptomatic fish compared to fingerling (P < 0.1). TCR-β showed significant (P < 0.05) down-regulation in symptomatic fish compared to asymptomatic ones and MHC-II resulted in down-regulation in a very significant (P < 0.01) manner in symptomatic trout compared to fingerling and asymptomatic. Concerning immunoglobulin genes expression, the level of mRNA transcript of IgT was significantly higher in symptomatic trout compared to fingerling (P < 0.05) and tended to be higher in asymptomatic trout compared to fingerling (P < 0.1). No significant differences were observed for IL-6, TNF-α, TLR5, MHC-I and IgM. In this study, a NIR based approach was used for the first time in the field of fish pathology/immunology with the aim of differentiating between healthy and diseased fish. Moreover, our results on immune related genes modulation highlighted how the outcome of a L. garvieae infection might be influenced by a specific gene expression pattern, which is crucial in the mode of action of trout immune system against L. garvieae.
Environmental surveillance and other control measures in the prevention of nosocomial fungal infections
(Clinical Microbiology and Infection, 2001) Muñoz, P.; Burillo Albizua, Almudena; Bouza Santiago, Emilio
The steady world-wide increase in the number of severely immunocompromised patients in most hospitals has made the control and prevention of nosocomial systemic fungal infections a critical quality-of-care standard. Early diagnosis and antifungal prophylaxis of these infections are complicated, so avoiding the acquisition of the pathogen in the case of Aspergillus and minimizing the predisposing risk factors in the case of Candida are more effective approaches. The maintenance of good air quality in critical areas in hospitals is mandatory to reduce the incidence of invasive aspergillosis. We review the currently available Center for Disease Control recommendations and report our own experiences in the field. The indications and problems of fungal environmental and patient surveillance are also discussed.

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