Examinando por Autor "Toro, M."

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    Clinical applications of ultrasound imaging in dentistry: A comprehensive literature review
    (Elsevier, 2024-06) Díaz, L.; Contador, R.; Albrecht, H.; Ibáñez, M.; Urrutia, P.; Bencze, B.; Toro, M.; Sáenz-Ravello, G.
    Ultrasonography (USG) is a diagnostic imaging technique based on the application of ultrasound waves with a frequency greater than 20.000 Hz, corresponding to the upper limit of audible human sound. The frequencies used in ultrasound imaging typically range from 1 MHz to 16 MHz. The principles and applications of this type of waves were first described by the Curie brothers and despite the time that has passed, their use in dentistry has not currently become widespread. The generation of images in USG is the result of the relationship and behavior experienced by different bodies and structures before the application of ultrasound pulses. Ultrasound imaging and its different modes have been used in different areas of dentistry, surgery, and maxillofacial aesthetics, in the description of cysts and tumors, identification of caries, dental fractures or cracks, periodontal bone defects, maxillofacial fractures, temporomandibular disorders, evaluation of periodontal and peri‑implant tissues, in addition to the identification of anatomical structures in the facial region. Although USG in dentistry offers considerable advantages over other frequently used diagnostic imaging techniques, further research is still required in relation to the equipment used for the study of the maxillofacial area, the different tissues and anatomical spaces that are part of it.
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    Evaluating the capacity of human gut microorganisms to colonize the zebrafish larvae (Danio rerio)
    (Frontiers Media, 2018-05) Valenzuela, M.-J.; Caruffo, M.; Herrera, Y.; Medina, D.A.; Coronado, M.; Feijóo, C.G.; Muñoz, S.; Garrido, D.; Troncoso, M.; Figueroa, G.; Toro, M.; Reyes-Jara, A.; Magne, F.; Navarrete, P.
    In this study we evaluated if zebrafish larvae can be colonized by human gut microorganisms. We tested two strategies: (1) through transplantation of a human fecal microbiota and (2) by successively transplanting aerotolerant anaerobic microorganisms, similar to the colonization in the human intestine during early life. We used conventionally raised zebrafish larvae harboring their own aerobic microbiota to improve the colonization of anaerobic microorganisms. The results showed with the fecal transplant, that some members of the human gut microbiota were transferred to larvae. Bacillus, Roseburia, Prevotella, Oscillospira, one unclassified genus of the family Ruminococcaceae and Enterobacteriaceae were detected in 3 days post fertilization (dpf) larvae; however only Bacillus persisted to 7 dpf. Successive inoculation of Lactobacillus, Bifidobacterium and Clostridioides did not improve their colonization, compared to individual inoculation of each bacterial species. Interestingly, the sporulating bacteria Bacillus clausii and Clostridioides difficile were the most persistent microorganisms. Their endospores persisted at least 5 days after inoculating 3 dpf larvae. However, when 5 dpf larvae were inoculated, the proportion of vegetative cells in larvae increased, revealing proliferation of the inoculated bacteria and better colonization of the host. In conclusion, these results suggest that it is feasible to colonize zebrafish larvae with some human bacteria, such as C. difficile and Bacillus and open an interesting area to study interactions between these microorganisms and the host. © 2018 Valenzuela, Caruffo, Herrera, Medina, Coronado, Feijóo, Muñoz, Garrido, Troncoso, Figueroa, Toro, Reyes-Jara, Magne and Navarrete.
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    Genomic diversity of listeria monocytogenes isolated from clinical and non-clinical samples in Chile
    (MDPI AG, 2018-08) Toledo, V.; Den Bakker, H.C.; Hormazábal, J.C.; González-Rocha, G.; Bello-Toledo, H.; Toro, M.; Moreno-Switt, A.I.
    Listeria monocytogenes is the causative agent of listeriosis, which is an uncommon but severe infection associated with high mortality rates in humans especially in high-risk groups. This bacterium survives a variety of stress conditions (e.g., high osmolality, low pH), which allows it to colonize different niches especially niches found in food processing environments. Additionally, a considerable heterogeneity in pathogenic potential has been observed in different strains. In this study, 38 isolates of L. monocytogenes collected in Chile from clinical samples (n = 22) and non-clinical samples (n = 16) were analyzed using whole genome sequencing (WGS) to determine their genomic diversity. A core genome Single Nucleotide Polymorphism (SNP) tree using 55 additional L. monocytogenes accessions classified the Chilean isolates in lineages I (n = 25) and II (n = 13). In silico, Multi-locus sequence typing (MLST) differentiated the isolates into 13 sequence types (ST) in which the most common were ST1 (15 isolates) and ST9 (6 isolates) and represented 55% of the isolates. Genomic elements associated with virulence (i.e., LIPI-1, LIPI-3, inlA, inlB, inlC, inlG, inlH, inlD, inlE, inlK, inlF, and inlJ) and stress survival (i.e., stress survival islet 1 and stress survival islet 2) were unevenly distributed among clinical and non-clinical isolates. In addition, one novel inlA premature stop codon (PMSC) was detected. Comparative analysis of L. monocytogenes circulating in Chile revealed the presence of globally distributed sequence types along with differences among the isolates analyzed at a genomic level specifically associated with virulence and stress survival. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.