Theaceae, with three tribes, nine genera and more than 200 species, are of great economic and ecological importance. Recent phylogenetic analyses based on plastomic data resolved the relationships ...among the three tribes and the intergeneric relationships within two of those tribes. However, generic-level relationships within the largest tribe, Theeae, were not fully resolved. The role of putative whole-genome duplication (WGD) events in the family and possible hybridization events among genera within Theeae also remain to be tested further.
Transcriptomes or low-depth whole-genome sequencing of 57 species of Theaceae, as well as additional plastome sequence data, were generated. Using a dataset of low-copy nuclear genes, we reconstructed phylogenetic relationships using concatenated, species tree and phylogenetic network approaches. We further conducted molecular dating analyses and inferred possible WGD events by examining the distribution of the number of synonymous substitutions per synonymous site (Ks) for paralogues in each species. For plastid protein-coding sequences , phylogenies were reconstructed for comparison with the results obtained from analysis of the nuclear dataset.
Based on the 610 low-copy nuclear genes (858 606 bp in length) investigated, Stewartieae was resolved as sister to the other two tribes. Within Theeae, the Apterosperma-Laplacea clade grouped with Pyrenaria, leaving Camellia and Polyspora as sister. The estimated ages within Theaceae were largely consistent with previous studies based mainly on plastome data. Two reticulation events within Camellia and one between the common ancestor of Gordonia and Schima were found. All members of the tea family shared two WGD events, an older At-γ and a recent Ad-β; both events were also shared with the outgroups (Diapensiaceae, Pentaphylacaceae, Styracaceae and Symplocaceae).
Our analyses using low-copy nuclear genes improved understanding of phylogenetic relationships at the tribal and generic levels previously proposed based on plastome data, but the phylogenetic position of the Apterosperma-Laplacea clade needs more attention. There is no evidence for extensive intergeneric hybridization within Theeae or for a Theaceae-specific WGD event. Land bridges (e.g. the Bering land bridge) during the Late Oligocene may have permitted the intercontinental plant movements that facilitated the putative ancient introgression between the common ancestor of Gordonia and Schima.
Acrocomia aculeata
is a tree palm species widely distributed throughout the Neotropics, from Mexico to Argentina including some Caribbean islands. The oil from the fruit is used for biodiesel ...production, human consumption, and biomass fuel. Despite the need to better understand its genetic diversity for commercial use and conservation
,
genetic diversity and structure knowledge of this species is scarce in Mesoamerica. We used microsatellite markers to analyze 185 samples of
A. aculeata
, from 18 sampling sites, that essentially covered geographic distribution of this species in Costa Rica. We found low genetic diversity across sampling sites, with He values below 0.50 which, is lower than diversity levels found in South America. Interestingly, samples collected in the national parks Santa Rosa and Rincon de la Vieja National exhibited the highest genetic diversity (He = 0.42 and He = 0.50, respectively). The 18 sampling sites were structured in three clusters. Cluster A contains samples collected in the lower northwestern Pacific, Central Pacific, and Central Region of Costa Rica. Cluster B consisted of samples from sites in the upper northwestern Pacific. Cluster C contains samples from the southeastern Pacific region, being largely separated from Clusters A and B which was supported by the highest differentiation coefficients. This is the first large genetic diversity study of
A. aculeata
in Mesoamerica; therefore, our results serve as reference for future studies on germplasm diversity studies in this region and a baseline for future conservation and management efforts of
A. aculeata
.
Guarea genus comprises tropical and subtropical terrestrial herbs inhabiting Central and South America. These plants, including Guarea guidonia (L.) Sleumer, have anti-inflammatory, analgesic, ...antibacterial, antiviral, and immune-enhancing properties.
Although various species of the Guarea genus are known for their medicinal properties, comprehensive data on their anti-inflammatory effects remain limited. Therefore, we investigated the NLRP3 inflammasome-inhibiting effects of the Guarea genus in this study.
To evaluate the anti-inflammatory activities of 18 members of the Guarea genus, we treated NLRP3 inflammasome activators with their extracts in LPS-primed J774A.1 and THP-1 cells. Cell viability was determined by water soluble tetrazolium salt (WST) and cytokine production, protein expression, and nuclear fractionation were determined by western blotting. Reactive oxygen species (ROS) production and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) oligomerization were measured using confocal microscopic analysis. Inflammation-induced zebrafish was used in the in vivo experiments.
Among the 18 Guarea members tested, Guarea microcarpa C. DC. extract (GM) exhibited no cytotoxicity and specifically suppressed the activation of the NLRP3 inflammasome, but not of the AIM2 or NLRC4 inflammasomes, by inhibiting the ATPase activity of NLRP3. This was achieved without affecting NF-κB signaling, potassium efflux, or intracellular ROS production, all of which are involved in NLRP3 activation. The reduced ATPase activity of NLRP3 led to decreased ASC oligomerization. Furthermore, GM exhibited anti-inflammatory effects in vivo. Additionally, GM treatment alleviated inflammation at the organismal level in an LPS-induced inflammation model using zebrafish embryos.
Our results demonstrate the anti-inflammatory effects of GM via suppressing the NLRP3 inflammasome. Therefore, GM can be a potential therapeutic candidate for various inflammatory diseases caused by aberrant NLRP3 inflammasome activation.
Trichospira verticillata is an annual herb that belongs to the family Asteraceae. Trichospira verticillata extract (TVE) elicits anti‐plasmodial activity; however, there has been no detailed report ...about its anti‐inflammatory effects and molecular mechanisms. In addition, herbal plants exhibit anti‐inflammatory effects by suppressing the NLRP3 inflammasome. Therefore, the primary goal of this study was to examine the effects of TVE on NLRP3 inflammasome activation by measuring interleukin‐1β (IL‐1β) secretion. We treated lipopolysaccharides (LPS)‐primed J774A.1 and THP‐1 cells with TVE, which attenuated NLRP3 inflammasome activation. Notably, TVE did not affect nuclear factor‐kappa B (NF‐κB) signalling or intracellular reactive oxygen species (ROS) production and potassium efflux, suggesting that it inactivates the NLRP3 inflammasome via other mechanisms. Moreover, TVE suppressed the formation of apoptosis‐associated speck‐like protein (ASC) speck and oligomerization. Immunoprecipitation data revealed that TVE reduced the binding of NLRP3 to NIMA‐related kinase 7 (NEK7), resulting in reduced ASC oligomerization and speck formation. Moreover, TVE alleviated neutrophilic asthma (NA) symptoms in mice. This study demonstrates that TVE modulates the binding of NLPR3 to NEK7, thereby reporting novel insights into the mechanism by which TVE inhibits NLRP3 inflammasome. These findings suggest TVE as a potential therapeutic of NLRP3 inflammasome‐mediated diseases, particularly NA.
The genus Daphnopsis has been traditionally used as a purgative, diuretic, stimulant, and psoriasis treatment. In this study, the anti-AD (atopic dermatitis) activities of the Daphnopsis ...costaricensis EtOH extract (DCE) were investigated in an oxazolone (OX)-induced mouse model of AD, and the anti-inflammatory effects of its active compounds were confirmed in PI-sensitized or IgE/DNP-BSA-sensitized RBL-2H3 cells. DCE improved the symptoms of OX-induced inflammatory dermatitis (swelling, erythema, and increased ear thickening) in OX-induced BALB/c mice ears and reduced epidermal thickness and mast cell infiltration. Eleven flavonoid compounds were isolated from DCE, and two compounds (7,8-dimethoxyflavone and 7,2’-dimethoxyflavone) significantly inhibited IL-4 overexpression in PI-induced RBL-2H3 cells and mast cell degranulation in IgE + DNP-BSA-induced RBL-2H3 cells. Our study indicates that DCE and two compounds (7,8-dimethoxyflavone and 7,2’-dimethoxyflavone) might effectively improve inflammatory and atopic skin symptoms.
Introduction
Tropical mountain rain forests (TMRF, natural forests at > 300 m asl) are globally important for biodiversity and ecosystem services and are believed to be highly vulnerable to climate ...change. But there are no specific approaches for rigorous assessment of their vulnerability at the landscape and local scales necessary for management for adaptation. We address the challenge of evaluating the ecological sensitivity to temperature of TMRF, applying a multidimensional approach in protected areas over a 440–2,950 m asl altitudinal gradient in Costa Rica, synthesizing results of a long-term research programme (2012-present). We evaluate the sensitivity to the current spatial temperature gradient of eleven ecosystem properties in three categories: forest composition and diversity, thermal characteristics of forest stands and forest structure and dynamics.
Methods
Data are from 29 to 32 plots of 50 m x 50 m (0.25 ha) distributed over the gradient, in which all trees, palms and tree ferns ≥ 10 dbh are identified to species and measured for recruitment, growth and mortality. An experimental study of leaf litter decomposition rates was carried out in twelve plots. Current and future (SSP 585, 2070) values of mean annual temperatures MAT were obtained from online climate surfaces. Thermal characteristics of forest stands were determined using MATs of species occurrences in GBIF and include a new index, the Community Thermal Capital Index (CTCI), calculated as CTI-MAT.
Results
We classified degrees of sensitivity to temperature as very weak, weak, moderate or substantial. All eleven ecosystem properties are substantially sensitive, so changes in their values are expected under rising temperatures. Species density, the community temperature index CTI, tree recruitment and mortality rates and leaf litter decomposition rates are
positively
related to temperature, while the community weighted mean thermal niche breadth, the CTCI, net basal area increments, stand basal area and carbon in aboveground biomass are
negatively
related. Results point to zones of vulnerability in the protected areas.
Discussion
In montane forests, positive values of the CTCI–climate credit– robust basal area growth and very low mortality and leaf litter decomposition rates suggest healthy ecosystems and no risk of mountaintop extinction. Lowland forests may be vulnerable to degradation and biotic attrition, showing current basal area loss, high mortality and climate debts. National and local actors are participating in a process of adoption of the sensitivity analysis and recommendations regarding zones of vulnerability.
Contexto: El proceso de digitalización de muestras de madera para su identificación y estudio ha tomado relevancia en la última década, por lo que es necesario considerar los aspectos fotográficos ...que generen representatividad de las imágenes con respecto a la muestra física.
Método: Se utilizaron diez especies maderables con no menos de 10 árboles muestreados, de cada individuo se extrajeron cinco cubos de madera de 10 mm de arista y se fotografiaron con un estereoscopio con un aumento de 20X bajo cuatro protocolos de luminosidad. En el proceso se evaluó la variación del color (bajo las coordenadas L*, a* y b*), diferencial de color (ΔE*) y chroma (ΔC*), además de la densidad y diámetro de vasos.
Resultados: Los resultados mostraron que la luminosidad del 50% fue la que mostró la mayor similitud con la colorimetría de la madera, obteniendo valores de ΔE* inferiores a 6 en todas las especies y valores de ΔC* dentro del rango óptimo de 5 a 7. Con respecto a la parte anatómica, se dio el mismo comportamiento con las diez especies, encontrando que los tratamientos de luminosidad al 25 y 50% no mostraron diferencias significativas, mientras las luminosidades al 75 y 100% tendieron a subestimar los valores.
Conclusiones: El tratamiento luminosidad al 25% es poco efectivo por el oscurecimiento de la superficie, mientras que las exposiciones al 75 y 100% tendieron a aclarar la superficie y subestimación de características anatómicas.
Aim
We sought to determine the relationship of forest composition and alpha diversity (the species diversity of a local assemblage) to altitude, soil, and spatial factors over a 440–2,950 m a.s.l ...gradient.
Location
Altitudinal gradient on the Caribbean slope of the Talamanca Cordillera, Costa Rica.
Taxon
Angiosperm and gymnosperm trees, palms, and tree ferns.
Methods
We measured and identified all stems ≥10 cm dbh in 32 0.25‐ha undisturbed rain forest plots over the gradient. We determined compositional patterns using Non‐Metric Multidimensional Scaling (NMS) ordination, and used linear regressions to explore the relationship between four alpha diversity metrics and altitude. With variation partitioning (VARPART), we determined the compositional variation explained by altitude, soil, and spatial variables quantified using Principle Components of Neighbor matrices.
Results
We identified 425 species. NMS axis 1 separated a lowland zone (440–1,120 m asl) from a transitional one dominated by holarctic Oreomunnea mexicana (1,400–1,600 m asl) and Quercus‐dominated forests at altitudes >2,100 m asl. The lowland zone was separated into two clusters of plots on NMS axis 2, the first in the 430–620 m asl range and the second at 1,000–1,120 masl. Regressions showed that all alpha diversity metrics were strongly negatively related to altitude (R2 > 0.78). Overall, adjusted R2 from VARPART was 0.43, with 0.30, 0.21, and 0.17 for altitude, soil, and space respectively. The respective adjusted R2 of individual matrices, on controlling for the other two, was 0.06, 0.05 and 0.09 (p < 0.001).
Main conclusions
There are two well‐defined forest compositional zones on this gradient—lowlands 430–1,120 m asl and montane forests >2,150 m asl—with a transitional zone at 1,400–1,600 m asl, where lowland tropical and montane holarctic species are found together. Montane forests are very distinct in their composition and low alpha diversity. Vegetation and soil respond to altitude, and therefore temperature, as an integrated system, a model that goes beyond niche assembly as shown by the significant effect of space in the VARPART.
In an altitudinal gradient on the Atlantic slope of the Talamanca Cordillera, Costa Rica, we found that forest composition and alpha diversity patterns show distinct lowland and montane zones and a transitional lower montane forest. Vegetation and soil respond to altitude (temperature), as an integrated system, beyond niche assembly.
El objetivo de la investigación ha sido el de confirmar o descartar la correlación de las variables asertividad y participación en estudiantes de pregrado de una universidad de Bogotá. Para la ...recopilación de los datos entre la población señalada, constituida por 1490 estudiantes de todos los programas académicos, se realizó un muestreo probabilístico por racimos sistemático, considerando un nivel de confianza de 95% y un margen de error de 5%, que determinó la participación final de 312 estudiantes. Luego se ejecutó el protocolo de investigación con un diseño no experimental, de alcance correlacional y momento transversal. El análisis descriptivo de los datos arrojó niveles altos de asertividad (76 percentiles promedio) y bajos de participación (36.7). En sintonía con ello, el análisis de estadística inferencial no paramétrico confirmó la correlación negativa y baja de estas dos variables (-.231). Altos niveles de asertividad en relación con niveles bajos de participación pueden sugerir 1) formas no convencionales de participación que han aparecido al mismo tiempo que las redes sociales; 2) conformidad ciudadana con un tipo de democracia liberal y representativa, y 3) la necesidad de llevar a cabo investigaciones que relacionen la participación con otra tipología comportamental más allá de los estilos clásicos.
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