32 research outputs found

    Growth inhibition and ultrastructural alterations induced by Δ24(25)-sterol methyltransferase inhibitors in Candida spp. isolates, including non-albicans organisms

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    <p>Abstract</p> <p>Background</p> <p>Although <it>Candida </it>species are commensal microorganisms, they can cause many invasive fungal infections. In addition, antifungal resistance can contribute to failure of treatment.</p> <p>The purpose of this study was to evaluate the antifungal activity of inhibitors of Δ<sup>24(25)</sup>-sterol methyltransferase (24-SMTI), 20-piperidin-2-yl-5α-pregnan-3β-20(R)-diol (AZA), and 24(R,S),25-epiminolanosterol (EIL), against clinical isolates of <it>Candida </it>spp., analysing the ultrastructural changes.</p> <p>Results</p> <p>AZA and EIL were found to be potent growth inhibitors of <it>Candida </it>spp. isolates. The median MIC<sub>50 </sub>was 0.5 μg.ml<sup>-1 </sup>for AZA and 2 μg.ml<sup>-1 </sup>for EIL, and the MIC<sub>90 </sub>was 2 μg.ml<sup>-1 </sup>for both compounds. All strains used in this study were susceptible to amphotericin B; however, some isolates were fluconazole- and itraconazole-resistant. Most of the azole-resistant isolates were <it>Candida </it>non-<it>albicans </it>(CNA) species, but several of them, such as <it>C. guilliermondii, C. zeylanoides</it>, and <it>C. lipolytica</it>, were susceptible to 24-SMTI, indicating a lack of cross-resistance. Reference strain <it>C. krusei </it>(ATCC 6258, FLC-resistant) was consistently susceptible to AZA, although not to EIL. The fungicidal activity of 24-SMTI was particularly high against CNA isolates. Treatment with sub-inhibitory concentrations of AZA and EIL induced several ultrastructural alterations, including changes in the cell-wall shape and thickness, a pronounced disconnection between the cell wall and cytoplasm with an electron-lucent zone between them, mitochondrial swelling, and the presence of electron-dense vacuoles. Fluorescence microscopy analyses indicated an accumulation of lipid bodies and alterations in the cell cycle of the yeasts. The selectivity of 24-SMTI for fungal cells versus mammalian cells was assessed by the sulforhodamine B viability assay.</p> <p>Conclusion</p> <p>Taken together, these results suggest that inhibition of 24-SMT may be a novel approach to control <it>Candida </it>spp. infections, including those caused by azole-resistant strains.</p

    BioTIME 2.0 : expanding and improving a database of biodiversity time series

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    Funding: H2020 European Research Council (Grant Number(s): GA 101044975, GA 101098020).Motivation: Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database. Main Types of Variables: Included The database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years. Spatial Location and Grain: Sampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size. Time Period and Grain: The earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample-level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric. Major Taxa and Level of Measurement: The database includes any eukaryotic taxa, with a combined total of 56,400 taxa. Software Format: csv and. SQL.Peer reviewe

    BioTIME 2.0 : expanding and improving a database of biodiversity time series

    Get PDF
    Motivation. Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database. Main Types of Variables Included. The database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years. Spatial Location and Grain. Sampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size. Time Period and Grain. The earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample-level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric. Major Taxa and Level of Measurement. The database includes any eukaryotic taxa, with a combined total of 56,400 taxa. Software Format. csv and. SQL

    Kinetics of Serum Myoglobin and Creatine Kinase Related to Exercise-Induced Muscle Damage and ACTN3 Polymorphism in Military Paratroopers Under Intense Exercise

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    Background: Physical conditioning is essential to meet the operational demands of military environments. However, high-intensity exercise provokes muscle microinjuries resulting in exercise-induced muscle damage. This condition is typically monitored using serum biomarkers such as creatine kinase (CK), myoglobin (MYO), and lactate dehydrogenase (LDH). Nevertheless, individual variability and genetic factors complicate the interpretation. In this context, the rs1815739 variant (ACTN3), the most common variant related to exercise phenotypes, hypothetically could interfere with the muscle physiological response. This study aimed to evaluate the kinetics of serum biomarkers during a high-intensity activity and their potential association with rs1815739 polymorphism. Materials and Methods: 32 male cadets were selected during the Army Paratrooper Course. Serum was obtained at six distinct moments while they performed regular course tests and recovery time. Borg scale was assessed in 2 moments (~11 and ~17). Results: Serum levels of CK, CK-MB, MYO, and LDH significantly increase after exercise, proportionally to Borg&rsquo;s level, following the applicability of longitudinal studies to understand biomarker levels in response to exercise. R allele carriers (ACTN3) were only slightly associated with greater levels of MYO and CK, mainly in relative kinetic levels, and especially at moments of greater physical demand/recovery. Although the ACTN3 was slightly related to different biomarker levels in our investigation, the success or healthiness in military activities is multifactorial and does not depend only on interindividual variability or physical capacity. Conclusions: Monitoring biomarkers and multiple genomic regions can generate more efficient exercise-related phenotype interventions

    Nosocomial candidiasis in Rio de Janeiro State: Distribution and fluconazole susceptibility profile

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    One hundred and forty-one Candida species isolated from clinical specimens of hospitalized patients in Rio de Janeiro, Brazil, during 2002 to 2007, were analized in order to evaluate the distribution and susceptibility of these species to fluconazole. Candida albicans was the most frequent species (45.4%), followed by C. parapsilosis sensu lato (28.4%), C. tropicalis (14.2%), C. guilliermondii (6.4%), C. famata (2.8%), C. glabrata (1.4%), C. krusei (0.7%) and C. lambica (0.7%). The sources of fungal isolates were blood (47.5%), respiratory tract (17.7%), urinary tract (16.3%), skin and mucous membrane (7.1%), catheter (5.6%), feces (2.1%) and mitral valve tissue (0.7%). The susceptibility test was performed using the methodology of disk-diffusion in agar as recommended in the M44-A2 Document of the Clinical and Laboratory Standards Institute (CLSI). The majority of the clinical isolates (97.2%) was susceptible (S) to fluconazole, although three isolates (2.1%) were susceptible-dose dependent (S-DD) and one of them (0.7%) was resistant (R). The S-DD isolates were C. albicans, C. parapsilosis sensu lato and C. tropicalis. One isolate of C. krusei was resistant to fluconazole. This work documents the high susceptibility to fluconazole by Candida species isolated in Rio de Janeiro, Brazil

    Nosocomial candidiasis in Rio de Janeiro State: Distribution and fluconazole susceptibility profile

    No full text
    One hundred and forty-one Candida species isolated from clinical specimens of hospitalized patients in Rio de Janeiro, Brazil, during 2002 to 2007, were analized in order to evaluate the distribution and susceptibility of these species to fluconazole. Candida albicans was the most frequent species (45.4%), followed by C. parapsilosis sensu lato (28.4%), C. tropicalis (14.2%), C. guilliermondii (6.4%), C. famata (2.8%), C. glabrata (1.4%), C. krusei (0.7%) and C. lambica (0.7%). The sources of fungal isolates were blood (47.5%), respiratory tract (17.7%), urinary tract (16.3%), skin and mucous membrane (7.1%), catheter (5.6%), feces (2.1%) and mitral valve tissue (0.7%). The susceptibility test was performed using the methodology of disk-diffusion in agar as recommended in the M44-A2 Document of the Clinical and Laboratory Standards Institute (CLSI). The majority of the clinical isolates (97.2%) was susceptible (S) to fluconazole, although three isolates (2.1%) were susceptible-dose dependent (S-DD) and one of them (0.7%) was resistant (R). The S-DD isolates were C. albicans, C. parapsilosis sensu lato and C. tropicalis. One isolate of C. krusei was resistant to fluconazole. This work documents the high susceptibility to fluconazole by Candida species isolated in Rio de Janeiro, Brazil
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