Differential Volatile Organic Compound Expression in the Interaction of Daldinia eschscholtzii and Mycena citricolor.

Fungi exhibit a wide range of ecological guilds, but those that live within the inner tissues of plants (also known as endophytes) are particularly relevant due to the benefits they sometimes provide to their hosts, such as herbivory deterrence, disease protection, and growth promotion. Recently, endophytes have gained interest as potential biocontrol agents against crop pathogens, for example, coffee plants (Coffea arabica). Published results from research performed in our laboratory showed that endophytic fungi isolated from wild Rubiaceae plants were effective in reducing the effects of the American leaf spot of coffee (Mycena citricolor). One of these isolates (GU11N) from the plant Randia grandifolia was identified as Daldinia eschscholtzii (Xylariales). Its antagonism mechanisms, effects, and chemistry against M. citricolor were investigated by analyzing its volatile profile alone and in the presence of the pathogen in contactless and dual culture assays. The experimental design involved direct sampling of agar plugs in vials for headspace (HS) and headspace solid-phase microextraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS) analysis. Additionally, we used ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS) to identify nonvolatile compounds from organic extracts of the mycelia involved in the interaction. Results showed that more volatile compounds were identified using HS-SPME (39 components) than those by the HS technique (13 components), sharing only 12 compounds. Statistical tests suggest that D. eschscholtzii inhibited the growth of M. citricolor through the release of VOCs containing a combination of 1,8-dimethoxynapththalene and terpene compounds affecting M. citricolor pseudopilei. The damaging effects of 1,8-dimethoxynaphthalene were corroborated in an in vitro test against M. citricolor pseudopilei; scanning electron microscopy (SEM) photographs confirmed structural damage. After analyzing the UHPLC-HRMS/MS data, a predominance of fatty acid derivatives was found among the putatively identified compounds. However, a considerable proportion of features (37.3%) remained unannotated. In conclusion, our study suggests that D. eschscholtzii has potential as a biocontrol agent against M. citricolor and that 1,8-dimethoxynaphthalene contributes to the observed damage to the pathogen's reproductive structures.

Interferome signature dynamics during the anti-dengue immune response: a systems biology characterization.

Dengue virus (DENV) infection manifests as a febrile illness with three distinct phases: early acute, late acute, and convalescent. Dengue can result in clinical manifestations with different degrees of severity, dengue fever, dengue hemorrhagic fever, and dengue shock syndrome. Interferons (IFNs) are antiviral cytokines central to the anti-DENV immune response. Notably, the distinct global signature of type I, II, and III interferon-regulated genes (the interferome) remains uncharacterized in dengue patients to date. Therefore, we performed an in-depth cross-study for the integrative analysis of transcriptome data related to DENV infection. Our systems biology analysis shows that the anti-dengue immune response is characterized by the modulation of numerous interferon-regulated genes (IRGs) enriching, for instance, cytokine-mediated signaling (e.g., type I and II IFNs) and chemotaxis, which is then followed by a transcriptional wave of genes associated with cell cycle, also regulated by the IFN cascade. The adjunct analysis of disease stratification potential, followed by a transcriptional meta-analysis of the interferome, indicated genes such as IFI27, ISG15, and CYBRD1 as potential suitable biomarkers of disease severity. Thus, this study characterizes the landscape of the interferome signature in DENV infection, indicating that interferome dynamics are a crucial and central part of the anti-dengue immune response.

YouTube™ as a source of tooth avulsion information: A video analysis study.

BACKGROUND/AIM: Evaluate the informative content in tooth avulsion videos intended for dentists available on YouTube™ and analyse their compliance with the International Association of Dental Traumatology (IADT) guidelines 2020. MATERIALS AND METHODS: Google Trends was used to identify the most searched term for tooth avulsion. Tooth avulsion-related videos in Brazilian Portuguese intended for dentists were searched on YouTube™ with a 12-month filter. Two raters reviewed these videos to extract their features and evaluate and qualify them with two 9-point checklists based on the IADT 2020 guidelines. The emergency steps for tooth avulsion at the accident site were assessed before, during and after clinical management; each step received 1 point if present and 0 points if absent. The final score ranged from 0 to 9 points on each checklist (18 points total), and the total score was used to classify the videos as having poor, moderate or rich content. Reliability and video quality were evaluated by an adapted version of the DISCERN tool and global quality scale (GQS), respectively. The data were analysed with the Mann-Whitney U-test, Pearson chi-square test, and the Kappa statistic (p < .05). RESULTS: Of 60 videos, 8 were included. All were uploaded by dental professionals or undergraduate students; the average duration was 11 min (range: 0.40-65 min), and the average number of views was 56.75. Half the videos (50%) had maximum completeness scores for questions about emergency dentist referral before clinical management, and more than half (75%) had maximum completeness regarding the steps required during and after treatment. Rich videos had higher GQS scores (p = .049) without significant correlation. CONCLUSIONS: Although most videos in Brazilian Portuguese were considered high-quality according to the IADT checklist, half of them presented partial absence of information regarding orientations at the accident site.

Methodology to Analyse Three-Dimensional Asymmetries in the Forces Applied to the Pedals in Cycling.

The asymmetries study between both legs of the forces applied to the pedals in cycling is important because they may affect the performance of the cyclist or prevent the occurrence of injuries. Studies focused on analysing asymmetries in forces tend to consider only the effective force, disregarding the three-dimensional nature of the force. Furthermore, these studies do not analyse the possible physical or neurological causes that may have led to the appearance of the asymmetries. This paper presents a methodology to carry out three-dimensional analysis of the asymmetries of the forces applied in both pedals and discriminate the possible sources of these asymmetries. Seven participants, amateurs and without pathologies, were analysed. Two commercial pedals were instrumented to measure the three components of the force applied to each pedal. The Normalized Symmetry Index (NSI) and the Cross Correlation Coefficient (CCC) were used for the asymmetries analysis. Results showed that both indexes need to be used in conjunction to analyse the causes of asymmetry in the pedal forces from a 3D perspective along the pedal cycle. The NSI is an index that makes it possible to evaluate asymmetry by considering only the value of the force applied by each leg at each instant. The CCC makes it possible to evaluate whether the temporal evolutions of the forces applied by each leg are similar. Preliminary results suggest that the proposed methodology is effective for analysing asymmetries in the forces in a pedalling cycle from a three-dimensional point of view. Forces in the sagittal plane showed a high level of symmetry. The lateral-medial force presented the highest level of asymmetry due to the difference in the magnitudes of the applied forces by both legs and the existing time shift between the two force patterns. The results of this work will allow for more complete and accurate three-dimensional dynamic analyses of the lower body during pedalling.

Design and Validation of a Device Attached to a Conventional Bicycle to Measure the Three-Dimensional Forces Applied to a Pedal.

Knowledge of the forces applied to the pedals during cycling is of great importance both from the point of view of improving sporting performance and medical analysis of injuries. The most common equipment for measuring pedal forces is usually limited to the study of forces in the sagittal plane. Equipment that measures three-dimensional forces tends to be bulky and to be incorporated into bicycles that are modified to accommodate it, which can cause the measurements taken to differ from those obtained in real pedalling conditions. This work presents a device for measuring the 3D forces applied to the pedal, attachable to a conventional bicycle and pedals, which does not alter the natural pedalling of cyclists. The equipment consists of four gauges located on the pedal axis and two on the crank, controlled by a microcontroller. Pedal forces measurements were made for six cyclists, with results similar to those shown in the literature. The correct estimation of the lateral-medial direction force is of great interest when evaluating a possible overload at the joints; it will also allow a comparison of the effectiveness index during pedalling, showing the role of this component in this index from a mechanical standpoint.

Anti-platelet activity and chemical characterization by UPLC-DAD-ESI-QTOF-MS of the main polyphenols in extracts from Psidium leaves and fruits.

In Costa Rica, two species of Psidium fruits, P. guajava and P. friedrichsthalianum, are widely consumed as food and used in folk medicine. Although studies have revealed the health effects of these fruits, there has been little research showing the antiplatelet activity of these species. This work evaluated the antiplatelet potential of aqueous extracts made from leaves and fruits of pink guava and Costa Rican guava. Platelet aggregation was induced by the platelet agonists ADP, TRAP-6, collagen and PMA. Platelet activation and secretion were studied using flow cytometry. The chemical profiles of the four extracts were characterized using UPLC-DAD-ESI-QTOF-MS. The studies revealed that the aqueous extracts of leaves and fruits of P. guajava and P. friedrichsthalianum inhibited platelet aggregation induced by ADP (4 µM), TRAP-6 (5 µM), collagen (1 µg mL-1) and PMA (100 nM), and the effect was dependent on the extract concentration. Extracts of leaves and fruits of pink guava and Costa Rican guava reduced secretion of P-selectin and activation of GP IIb/IIIa. The extracts of leaves and fruits of pink guava and Costa Rican guava proved to be a rich source of phenolic compounds, mainly quercetin aglycones and proanthocyanidins derived from (epi) catechin units. Other compounds such as ellagitannins, and benzophenones were also putatively identified. This research showed that P. guajava and P. friedrichsthalianum could potentially be used for the prevention of thrombotic events.

Reproducible molecular networking of untargeted mass spectrometry data using GNPS.

Global Natural Product Social Molecular Networking (GNPS) is an interactive online small molecule-focused tandem mass spectrometry (MS2) data curation and analysis infrastructure. It is intended to provide as much chemical insight as possible into an untargeted MS2 dataset and to connect this chemical insight to the user's underlying biological questions. This can be performed within one liquid chromatography (LC)-MS2 experiment or at the repository scale. GNPS-MassIVE is a public data repository for untargeted MS2 data with sample information (metadata) and annotated MS2 spectra. These publicly accessible data can be annotated and updated with the GNPS infrastructure keeping a continuous record of all changes. This knowledge is disseminated across all public data; it is a living dataset. Molecular networking-one of the main analysis tools used within the GNPS platform-creates a structured data table that reflects the molecular diversity captured in tandem mass spectrometry experiments by computing the relationships of the MS2 spectra as spectral similarity. This protocol provides step-by-step instructions for creating reproducible, high-quality molecular networks. For training purposes, the reader is led through a 90- to 120-min procedure that starts by recalling an example public dataset and its sample information and proceeds to creating and interpreting a molecular network. Each data analysis job can be shared or cloned to disseminate the knowledge gained, thus propagating information that can lead to the discovery of molecules, metabolic pathways, and ecosystem/community interactions.

Shifts in the diversity of an amphibian community from a premontane forest of San Ramón, Costa Rica

Biological communities are experiencing rapid shifts of composition in Neotropical ecosystems due to several factors causing population declines. However, emerging evidence has provided insights on the adaptive potential of multiple species to respond to illnesses and environmental pressures. In Costa Rica, the decline of amphibian populations is a remarkable example of these changes. Here we provide evidence of variation in the amphibian richness of a premontane forest of San Ramón (Costa Rica) across a ~30 year period. We also quantified changes in the composition and abundance of the leaf-litter frog community occurring in the same premontane forest, by comparing diversity data with a difference of ~18 years. We evaluated the similarity of species richness from 1980s to 2010s based on several sources, and the dissimilarity of species diversity in the site comparing 28 standardized surveys from 1994-1995 and 2011-2012. We compared the relative abundance of some frogs that inhabit the leaf-litter layer between these same periods. Our results show that there is more similarity in amphibian richness between 1980s and 2010s (~ 52 %) than between 1980s and 1990s (~ 40 %). The richness of leaf-litter anurans was ~ 65 % similar between 1990s and 2010s. The diversity of leaf-litter anuran was clearly different between 1994-1995 and 2011-2012, and it was clustered among those periods. We determined that the amphibian community in this premontane forest drastically changed: many species have disappeared, or gradually declined through the decades (e.g. Pristimantis ridens, P. cruentus, Craugastor bransfordii) as in other well studied localities of Costa Rica, while some few species flourished after being almost absent from the site in the 1990s (e.g. Craugastor crassidigitus, Lithobates warszewistchii). Currently dominant species such as C. crassidigitus would be using developed resistance against Bd-fungus as an advantage (apparent competition) in the premontane forest where the disease is more virulent than in lowlands. Our analysis supports the hypothesis of individualized responses of anuran populations under distinct site and elevations. We suggest to continue monitoring the amphibian communities of premontane tropical forests to understand how this ecosystem gradually resist and adapts to this catastrophic time of biodiversity loss.

Las comunidades biológicas están experimentando rápidos cambios de composición en los ecosistemas neotropicales debido a varios factores que causan disminuciones de las poblaciones. Sin embargo, la evidencia emergente ha proporcionado información sobre el potencial de adaptación de múltiples especies para responder a enfermedades y presiones ambientales. En Costa Rica, el declive de las poblaciones de anfibios es un ejemplo notable de estos cambios. Aquí proporcionamos evidencia de variación en la riqueza de anfibios de un bosque premontano de San Ramón (Costa Rica) en un período de ~ 30 años. También cuantificamos los cambios en el ensamblaje, y las oscilaciones poblacionales, de la comunidad de ranas de hojarasca que ocurren en el mismo bosque premontano, tras comparar datos de diversidad con una diferencia de ~ 18 años. Evaluamos la similitud de la riqueza de especies desde la década de 1980 hasta la de 2010 basados en varias fuentes, así como la disimilitud de la diversidad de especies en el sitio comparando 28 muestreos estandarizados entre 1994-1995 y 2011-2012. Comparamos la abundancia relativa de algunas ranas que habitan la hojarasca entre 1994-1995 y 2011-2012. Nuestros resultados muestran que existe una similitud un poco mayor en la riqueza de anfibios entre los años 1980 y 2010 que entre los 1980 y 1990 (~ 40 %). La riqueza de los anuros de la hojarasca fue aproximadamente un 65 % similar entre la década de 1990 y 2010. La diversidad de anuros de la hojarasca fue claramente diferente entre 1994-1995 y 2011-2012, y se agrupó entre esos períodos. Determinamos que la comunidad de anfibios en este bosque premontano cambió drásticamente: muchas especies han desaparecido o han disminuido gradualmente a lo largo de las décadas como en otras localidades bien estudiadas de Costa Rica (por ejemplo, Pristimantis ridens, P. cruentus, Craugastor bransfordii), mientras algunas pocas especies florecieron tras casi desaparecer de nuestro sitio en la década de 1990 (por ejemplo, Craugastor crassidigitus, Lithobates warszewistchii). Actualmente, las especies dominantes como C. crassidigitus podrían tener resistencia contra el hongo quitridio, desarrollada como una ventaja (competición aparente) en el bosque premontano donde la enfermedad es más virulenta que en las tierras bajas. Nuestro análisis apoya la hipótesis de las respuestas individualizadas de las poblaciones de anuros en distintos sitios y elevaciones. Sugerimos continuar con el monitoreo de las comunidades de anfibios de los bosques neotropicales premontanos para comprender cómo este ecosistema resiste gradualmente y se adapta a este momento catastrófico de pérdida de biodiversidad.

Itaca, Nueva York, Estados Unidos de América. Zona Tropical Publications

ook review directed to local tourism guides, naturalists and biologists on the new book "Amphibians of Costa Rica: A field guide" by TwanLeenders.

Calcium and phosphate release from resin-based materials containing different calcium orthophosphate nanoparticles.

The study compared ion release from resin-based materials containing calcium orthophosphates. Amorphous calcium phosphate (ACP), dicalcium phosphate anhydrous (DCPA), dicalcium phosphate dihydrate (DCPD), and tricalcium phosphate (ß-TCP) nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), and surface area (nitrogen adsorption isotherms, BET method). Nanoparticles were added to a dimethacrylate-based resin and materials were tested for degree of conversion (DC) and calcium/phosphate release up to 28 days under pH 5.5 and 7.0. Data were analyzed by ANOVA/Tukey test (alpha: 0.05).The crystallinity of DCPA, DCPD, and ß-TCP were confirmed, as well as the ACP amorphous nature. DCPD and ß-TCP presented larger agglomerates than DCPA and ACP. The surface area of ACP was 5-11 times higher than those of the other nanoparticles. Materials showed similar DC. The material containing ACP released significantly more ions than the others, which released similar amounts of calcium and, in most cases, phosphate. Ion release was not affected by pH. Calcium release decreased between 7 and 21 days, while phosphate levels remained constant after 14 days. In conclusion, ACP higher ion release can be ascribed to its high surface area. DCPA, DCPD, and ß-TCP had similar performances as ion-releasing fillers.

Aderência de Actinobacillus actinomycetemcomitans às células epiteliais bucais: estabilidade e aspectos ultra-estruturais / Actinobacillus actinomycetemcomitans attached to oral epithelial cells: stability and ultrastructural aspects

Actinobacillus actinomycetemcomitans é considerado um importante patógeno periodontal, particularmente na periodontite juvenil localizada. O mecanismo de adesäo bacteriana às células epiteliais bucais (CEB), aos dentes e a outras bactérias, constitui-se o passo inicial na colonizaçäo e patogênese nos quadros de gengivite e periodontite. neste estudo, avaliou-se a aderência às CEB, a sua variabilidade e os aspectos ultra-estruturais de 21 isolados e de uma cepa de referência de A. actinomycetemcomitans, quando submetidos a repiques sucessivos. Todos os isolados testados aderiram às CEB e os repiques sucessivos determinaram variaçöes nas taxas de aderência de cada isolado. Os isolados que apresentaram altos índices de aderência também produziram quantidades elevadas de componentes extracelulares, tais como fímbrias, vesículas e/ou material amorfo extracelular