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1.
Artículo en Inglés | MEDLINE | ID: mdl-38963604

RESUMEN

Since the inception of in vitro fertilization (IVF), monitoring of controlled ovarian stimulation (COS) has traditionally involved numerous appointments for ultrasound and laboratory testing to guide medication use and dosing, determine trigger timing, and allow for measures to reduce the risk of ovarian hyperstimulation syndrome (OHSS). Recent advances in the field of assisted reproductive technology (ART) have called into question the timing and frequency of COS monitoring appointments, as discussed in this commentary.

2.
Plants (Basel) ; 13(1)2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38202439

RESUMEN

When colonizing new ranges, plant populations may benefit from the absence of the checks imposed by the enemies, herbivores, and pathogens that regulated their numbers in their original range. Therefore, rates of plant damage or infestation by natural enemies are expected to be lower in the new range. Exposing both non-native and native plant populations in the native range, where native herbivores are present, can be used to test whether resistance mechanisms have diverged between populations. Datura stramonium is native to the Americas but widely distributed in Spain, where populations show lower herbivore damage than populations in the native range. We established experiments in two localities in the native range (Mexico), exposing two native and two non-native D. stramonium populations to natural herbivores. Plant performance differed between the localities, as did the abundance of the main specialist herbivore, Lema daturaphila. In Teotihuacán, where L. daturaphila is common, native plants had significantly more adult beetles and herbivore damage than non-native plants. The degree of infestation by the specialist seed predator Trichobaris soror differed among populations and between sites, but the native Ticumán population always had the lowest level of infestation. The Ticumán population also had the highest concentration of the alkaloid scopolamine. Scopolamine was negatively related to the number of eggs deposited by L. daturaphila in Teotihuacán. There was among-family variation in herbivore damage (resistance), alkaloid content (scopolamine), and infestation by L. daturaphila and T. soror, indicating genetic variation and potential for further evolution. Although native and non-native D. stramonium populations have not yet diverged in plant resistance/constitutive defense, the differences between ranges (and the two experimental sites) in the type and abundance of herbivores suggest that further research is needed on the role of resource availability and adaptive plasticity, specialized metabolites (induced, constitutive), and the relationship between genealogical origin and plant defense in both ranges.

3.
G3 (Bethesda) ; 14(2)2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38113048

RESUMEN

Plant resistance refers to the heritable ability of plants to reduce damage caused by natural enemies, such as herbivores and pathogens, either through constitutive or induced traits like chemical compounds or trichomes. However, the genetic architecture-the number and genome location of genes that affect plant defense and the magnitude of their effects-of plant resistance to arthropod herbivores in natural populations remains poorly understood. In this study, we aimed to unveil the genetic architecture of plant resistance to insect herbivores in the annual herb Datura stramonium (Solanaceae) through quantitative trait loci mapping. We achieved this by assembling the species' genome and constructing a linkage map using an F2 progeny transplanted into natural habitats. Furthermore, we conducted differential gene expression analysis between undamaged and damaged plants caused by the primary folivore, Lema daturaphila larvae. Our genome assembly resulted in 6,109 scaffolds distributed across 12 haploid chromosomes. A single quantitative trait loci region on chromosome 3 was associated with plant resistance, spanning 0 to 5.17 cM. The explained variance by the quantitative trait loci was 8.44%. Our findings imply that the resistance mechanisms of D. stramonium are shaped by the complex interplay of multiple genes with minor effects. Protein-protein interaction networks involving genes within the quantitative trait loci region and overexpressed genes uncovered the key role of receptor-like cytoplasmic kinases in signaling and regulating tropane alkaloids and terpenoids, which serve as powerful chemical defenses against D. stramonium herbivores. The data generated in our study constitute important resources for delving into the evolution and ecology of secondary compounds mediating plant-insect interactions.


Asunto(s)
Datura stramonium , Animales , Datura stramonium/genética , Herbivoria , Insectos , Ecología , Plantas , Cromosomas
4.
Rev. Bras. Saúde Mater. Infant. (Online) ; 24: e20220431, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1558984

RESUMEN

Abstract Objectives: identify the sociodemographic conditions of the community and determine the prevalence of the nutritional status of children under six years of age in the Nasa Paéz Indigenous Reserve, Rionegro-Huila, Colombia. Methods: cross-sectional descriptive study whose data was obtained from two databases, one of sociodemographic conditions and other anthropometric measurements of children under six years of age. The sample corresponded to the total population of less than six years. The data was analyzed using descriptive statistics using the R Studio 3.4 software. Results: 98.6% of the population is enrolled in the health system. Water consumption comes from 71.6% of non-potable sources. 25.5% of the population has access to wastewater disposal systems. Regarding nutritional status, the prevalence of delay in growth and risk of delay in growth is 43.3% in the population under six months and 69.4% in those aged between six months and six years. Furthermore, 34.3% of children under six months of age are at risk of being overweight. Conclusions: sociodemographic conditions are determined by different inequities, low education levels, inadequate housing, drinking water consumption, as well as a high prevalence of child malnutrition.


Resumen Objetivos: identificar las condiciones sociodemográficas de la comunidad y determinar la prevalencia del estado nutricional de niños menores de seis años en el Resguardo Indígena Nasa Paéz, Rionegro-Huila, Colombia. Métodos: estudio descriptivo transversal cuyos datos se obtuvieron de dos bases de datos, una de las condiciones sociodemográficas y otra de medidas antropométricas de niños menores de seis años. La muestra correspondió a la totalidad población menor seis años. Los datos se analizaron mediante estadística descriptiva utilizando el software R Studio 3.4. Resultados: el 98,6% de la población está inscrito en el sistema de salud. El consumo de agua proviene en un 71,6% de fuentes no potables. El 25,5% de la población tiene acceso a sistemas de eliminación de aguas residuales. En cuanto al estado nutricional, la prevalencia de retraso en el crecimiento y riesgo de retraso en el crecimiento es del 43,3% en la población menor de seis meses y del 69,4% en edad entre los seis meses a seis años. Además, el 34,3% de los niños menores de seis meses estaban en riesgo de tener sobrepeso. Conclusiones: las condiciones sociodemográficas están determinadas por diferentes inequidades, bajos niveles de educación, vivienda inadecuada, consumo de agua no potable, así como por una alta prevalencia de malnutrición infantil.

5.
Ecol Evol ; 13(12): e10794, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38077505

RESUMEN

The expression of plant resistance traits against arthropod herbivores often comes with costs to other essential plant functions such as growth and fitness. These trade-offs are shaped by the allocation of limited resources. However, plants might also possess the capability to allocate resources to both resistance and growth, thereby ensuring their survival when under herbivore attacks. Additionally, the extent of damage caused by herbivores could vary across different years or seasons, subsequently impacting plant performance. In this study, we aimed to investigate how the annual variations in herbivore abundance and damage levels affect plant performance. We generated F2 progeny through a cross between two populations of the annual herb Datura stramonium (Solanaceae). These populations are known to have differing levels of chemical defense and herbivory. These F2 plants were cultivated in a common natural environment for two consecutive years (2017 and 2018). Our findings reveal that plants with higher resistance, attained higher seed production but this trend was evident only during 2018. This relationship coincided with a five-fold increase in the abundance of Lema daturaphila (Chrysomelidae) larvae in 2018. Indeed, the plants experienced a 13-fold increase in damage during this second year of study. Furthermore, our results indicated that there was no trade-off between resistance, growth, and fitness in either of the 2 years. In contrast, during 2018, when plants faced stronger herbivore pressure, they allocated all available nutritional resources to enhance both resistance and growth. Our study highlights how the selection for plant resistance is dependent upon the inter-annual variation in herbivore abundance.

6.
Front Reprod Health ; 5: 1239175, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37965590

RESUMEN

The present study compares two protocols for ovarian controlled stimulation in terms of number of cumulus-oocyte complexes and metaphase II oocytes. We employed a single injection of 150mcg of corifollitropin alfa after a 7-day oral contraceptive pill-free interval for TAIL group and a conventional administration of corifollitropin alfa after a 5-day OCP-free interval with additional rFSH from 8th of ovarian controlled stimulation. Prospective, randomized, comparative, non-inferiority, opened and controlled trial carried out in 180 oocyte donors 31 were excluded, 81 were randomized to the control group and 68 to the TAIL group. No differences were found in the number of follicles larger than 14 and 17 mm at triggering day. However, a lower number of cumulus-oocyte complexes and metaphase II oocytes were obtained in TAIL group compared to the control group, expressed as median (interquartile range): 10.5 (5.5-19) vs. 14 [11-21] and 9 (4-13) vs. 12 (9-17) respectively. Additionally, the incidence of failed retrieval or metaphase II oocytes = 0 was higher in TAIL group 7(10.3%) vs. 1(1.2%) p = 0.024. The use of a single injection of corifollitropin alfa after a 7-day oral contraceptive pill-free interval in oocyte donors resulted in a lower number of cumulus-oocyte complexes and metaphase II oocytes. No additional rFSH was administered in this group. Clinical Trial Registration: https://www.clinicaltrialsregister.eu/ctr-search/trial/2019-001343-44/results.

7.
Front Endocrinol (Lausanne) ; 14: 1285040, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38027116

RESUMEN

Introduction: Embryo implantation is a complex and poorly understood process. Most studies to date have focused on the analysis of the endometrium at the end of the estrogenic phase, while the available data on its importance after secretory transformation are limited and inconsistent. Current evidence does not allow for a conclusive interpretation of the changes observed in the pre-implantation endometrium, whether in the natural or replacement cycle, and their relevance in the development of a pregnancy or the implications for clinical practice. Methods: Multicenter prospective observational cohort study. Based on our sample size calculation, the study group will consist of 206 women (exposed or "compaction" group: 103 women with a decrease of ≥ 5% in endometrial thickness between the estrogenic phase and the day of embryo transfer; non-exposed "non-compaction" group: 103 women with similar or greater endometrial thickness between these time points). The main objective of this study is to compare the ongoing pregnancy rates in natural cycles for euploid embryo transfer in patients who present endometrial compaction at the time of transfer versus those who with a stable or greater endometrial thickness with respect to the estrogenic phase. The estimated duration of the study is 30 months. Inclusion criteria are: 18 to 50 years of age, with primary or secondary infertility, subjected to endometrial preparation in a modified natural cycle for transfer of a genetically euploid blastocyst, from their own oocyte or oocyte donation, with a normal uterine cavity. Exclusion criteria are: uterine or endometrial disease (e.g., multiple myomatosis, severe adenomyosis, Asherman syndrome, refractory endometrium), conditions that prevent correct ultrasound assessment (tilted uterus), or a history of recurrent implantation failure or repeated miscarriages. Discussion: The findings from this study will provide valuable insights into the potential influence of the "endometrial compaction" phenomenon on reproductive outcomes during natural cycle endometrial preparation. By examining this aspect, we aim to contribute to a better understanding of the factors that may impact successful outcomes in fertility treatments.


Asunto(s)
Implantación del Embrión , Transferencia de Embrión , Embarazo , Humanos , Femenino , Estudios Prospectivos , Índice de Embarazo , Transferencia de Embrión/métodos , Endometrio , Estudios Observacionales como Asunto , Estudios Multicéntricos como Asunto
8.
PLoS One ; 18(9): e0291945, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37756353

RESUMEN

Knowing how species and communities respond to environmental change is fundamental in the context of climate change. The search for patterns of abundance and phenotypic variation along altitudinal gradients can provide evidence on adaptive limits. We evaluated the species abundance and the variation in morphometric and stomatal characters in five tree ferns species (Cyathea fulva, C. divergens, C. myosuroides, Alsophila firma and Gymnosphaera salvinii) distributed along an elevation gradient in a well-preserved Mexican cloud forest. Variation at the community and species level was assessed using exploratory and multivariate data analysis methods. We wanted to explore if the species abundance is environmentally determined, to determine the degree of variation along the elevation gradient, to test for differences between zones and associations with elevation, humidity and soil nutrients, and to assess contribution of the intra- and interspecific variation to the community response to elevation and soil nutrients. The studied fern community showed strong species turnover along the elevation gradient, with some influence of soil nutrient concentration, supporting environmental determinism. All measured characters displayed variation along the gradient. Stomatal characters (size and density) had significantly less variation than morphometric characters (trunk diameter, stipe length and blade length), but stomatal density also shows interesting intraspecific patterns. In general, patterns within the fern community suggest a strong influence of species identity, especially of species inhabiting the lower edge of the cloud forest, which showed the clearest morphometric and stomatal patterns, associated to contrasting environments rather than to changes in elevation. The coincidence between morphometric and stomatal patterns in this area suggest hydraulic adjustments in response to contrasting environments. Our results provide evidence that tree ferns species respond to environmental changes through adjustments of morphometric plasticity and stomatal density, which is relevant to predict possible responses to variation in environmental conditions resulting from climate change.

9.
Plants (Basel) ; 12(14)2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37514225

RESUMEN

Macroevolutionary patterns in the association between plant species and their herbivores result from ecological divergence promoted by, among other factors, plants' defenses and nutritional quality, and herbivore adaptations. Here, we assessed the performance of the herbivores Lema trilineata daturaphila, a trophic specialist on Datura, and Spodoptera frugiperda, a polyphagous pest herbivore, when fed with species of Datura. We used comparative phylogenetics and multivariate methods to examine the effects of Datura species' tropane alkaloids, leaf trichomes, and plant macronutrients on the two herbivores´ performances (amount of food consumed, number of damaged leaves, larval biomass increment, and larval growth efficiency). The results indicate that species of Datura do vary in their general suitability as food host for the two herbivores. Overall, the specialist performs better than the generalist herbivore across Datura species, and performance of both herbivores is associated with suites of plant defenses and nutrient characteristics. Leaf trichomes and major alkaloids of the Datura species are strongly related to herbivores' food consumption and biomass increase. Although hyoscyamine better predicts the key components of the performance of the specialist herbivore, scopolamine better predicts the performance of the generalist; however, only leaf trichomes are implicated in most performance components of the two herbivores. Nutrient quality more widely predicts the performance of the generalist herbivore. The contrasting effects of plant traits and the performances of herbivores could be related to adaptive differences to cope with plant toxins and achieve nutrient balance and evolutionary trade-offs and synergisms between plant traits to deal with a diverse community of herbivores.

10.
Plants (Basel) ; 12(3)2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36771638

RESUMEN

Agricultural losses brought about by insect herbivores can be reduced by understanding the strategies that plants use against insect herbivores. The two main strategies that plants use against herbivory are resistance and tolerance. They are, however, predicted to be mutually exclusive, yet numerous populations have them both (hence a mixed defense strategy). This has been explained, among other alternatives, by the non-linear behavior of the costs and benefits of resistance and tolerance and their interaction with plants' mating system. Here, we studied how non-linearity and mating system affect the evolutionary stability of mixed defense strategies by means of agent-based model simulations. The simulations work on a novel model that was built upon previous ones. It incorporates resistance and tolerance costs and benefits, inbreeding depression, and a continuously scalable non-linearity. The factors that promoted the evolutionary stability of mixed defense strategies include a multiplicative allocation of costs and benefits of resistance and tolerance, a concave non-linearity, non-heritable selfing, and high tolerance costs. We also found new mechanisms, enabled by the mating system, that are worth considering for empirical studies. One was a double trade-off between resistance and tolerance, predicted as a consequence of costs duplication and the inducibility of tolerance, and the other was named the resistance-cost-of-selfing, a term coined by us, and was derived from the duplication of costs that homozygous individuals conveyed when a single resistance allele provided full protection.

11.
Glob Health Promot ; 30(2): 86-94, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36268647

RESUMEN

RESUMEN: La soberanía alimentaria es el derecho colectivo a decidir sobre la producción, distribución y consumo de alimentos y promueve la generación de suministros alimenticios para el consumo local de tal forma que los consumidores queden resguardados de la volatilidad de los precios de mercados internacionales. En los pueblos indígenas esta tendencia resulta trascendental para hacer frente a condiciones de inequidad histórica que han impactado negativamente su salud pública. No obstante, es ignorada en algunos casos y en otros reemplazada por nociones centradas en la seguridad alimentaria, término alineado con políticas transnacionales derivadas del modelo económico dominante. OBJETIVO: analizar con tres comunidades indígenas de Colombia las perspectivas de soberanía alimentaria y su influencia en la salud. MÉTODO: investigación participativa basada en la comunidad, para recolectar datos mediante grupos de discusión, entrevistas y observación. La población de estudio fueron tres comunidades indígenas del sur de Colombia. La selección de participantes se realizó según su trayectoria en la comunidad. RESULTADOS: las comunidades entienden la soberanía alimentaria como la conservación de semillas nativas y alimentos propios, vista como oportunidad para el cuidado de la salud. Su debilitamiento se relaciona con el desarrollo de enfermedades de las personas y de la madre tierra. Para su fortalecimiento identificaron el tul, el yatul y la chagra (huerta) que reafirman la unión familiar, contribuyen a la recuperación de modos de producción desde la sabiduría ancestral y se posicionan como alternativa para la sostenibilidad económica. CONCLUSIÓN: la soberanía alimentaria conserva los saberes y prácticas tradicionales para una alimentación propia, debilitada por los sistemas agroindustriales. Es asumida como iniciativa local suscrita en un proyecto global de resistencia política y económica para la salud colectiva de los pueblos.


Asunto(s)
Estudios Retrospectivos , Humanos , Colombia
12.
Physis (Rio J.) ; 33: e33089, 2023. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1529163

RESUMEN

Resumen La autonomía alimentaria permite a las comunidades determinar sus prácticas alimentarias, comenzando con la producción agrícola en sus territorios garantizando la economía propia y la armonía con la madre tierra, en este contexto, la pandemia por COVID-19 generó cambios en las practicas sociales en las comunidades indígenas, incluidas sus prácticas alimentarias. Objetivo: Describir prácticas de autonomía alimentaria revitalizadas a partir del confinamiento por COVID-19 en una comunidad indígena Nasa del sur de Colombia. Método: Estudio cualitativo orientado en investigación participativa basada en comunidad (CBPR) realizado en una comunidad indígena Nasa del sur de Colombia. La recolección e interpretación de información se efectuó con técnicas de la investigación cualitativa: codificación abierta y axial y hasta llegar a la descripción de categorías emergentes. Resultados: Se fortalecieron prácticas ancestrales del sistema alimentario para mejorar el acceso a los alimentos sanos producidos en sus territorios, dentro de las que se destacan: tul (huerta familiar), trueque, mano-cambio, mercado Nasa y recetas tradicionales. Conclusiones: El confinamiento representó una oportunidad para retomar y revitalizar las prácticas alimentarias ancestrales de la comunidad que respondieron a necesidades concretas de salud y de alimentación, fortaleciendo el tejido social y la identidad indígena, acciones que pueden trascender a políticas públicas, planes de vida y aspiraciones de buen vivir.


Abstract Food autonomy allows communities to determine their food practices, starting with agricultural production in their territories, guaranteeing their own economy and harmony with Mother Earth. In this context, the COVID-19 pandemic generated changes in social practices in the communities. indigenous communities, including their food practices. Objective: Describe food autonomy practices revitalized following the COVID-19 confinement in a Nasa indigenous community in southern Colombia. Method: Qualitative study oriented on community-based participatory research (CBPR) carried out in a Nasa indigenous community in southern Colombia. The collection and interpretation of information was carried out with qualitative research techniques: open and axial coding and until reaching the description of emerging categories. Results: Ancestral practices of the food system were strengthened to improve access to healthy foods produced in their territories, among which the following stand out: tul (family garden), barter, hand-exchange, Nasa market and traditional recipes. Conclusions: Confinement represented an opportunity to resume and revitalize the community's ancestral food practices that responded to specific health and food needs, strengthening the social fabric and indigenous identity, actions that can transcend public policies, life plans and aspirations for a good life.


Abstract A autonomia alimentar permite que as comunidades determinem suas práticas alimentares, começando pela produção agrícola em seus territórios, garantindo sua própria economia e harmonia com a Mãe Terra. Nesse contexto, a pandemia da Covid-19 gerou mudanças nas práticas sociais nas comunidades indígenas, incluindo suas práticas alimentares. Objetivo: Descrever as práticas de autonomia alimentar revitalizadas após o confinamento da COVID-19 em uma comunidade indígena Nasa no sul da Colômbia. Método: Estudo qualitativo orientado à pesquisa participativa de base comunitária (CBPR) realizada em uma comunidade indígena Nasa no sul da Colômbia. A coleta e interpretação das informações foram realizadas com técnicas de pesquisa qualitativa: codificação aberta e axial e até chegar à descrição das categorias emergentes. Resultados: As práticas ancestrais do sistema alimentar foram fortalecidas para melhorar o acesso aos alimentos saudáveis produzidos em seus territórios, entre os quais se destacam: tul (horta familiar), escambo, troca de mãos, mercado Nasa e receitas tradicionais. Conclusões: O confinamento representou uma oportunidade para retomar e revitalizar as práticas alimentares ancestrais da comunidade que respondiam às necessidades específicas de saúde e alimentação, fortalecendo o tecido social e a identidade indígena, ações que podem transcender as políticas públicas, os planos de vida e as aspirações por uma vida boa.

13.
PeerJ ; 10: e13553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35910763

RESUMEN

Background: Characterized by an inflammatory pathogenesis, acne is the most common skin disorder worldwide. Altered sebum production, abnormal proliferation of keratinocytes, and microbiota dysbiosis represented by disbalance in Cutibacterium acnes population structure, have a synergic effect on inflammation of acne-compromised skin. Although the role of C. acnes as a single factor in acne development is still under debate, it is known that skin and skin-resident immune cells recognize this bacterium and produce inflammatory markers as a result. Control of the inflammatory response is frequently the target for acne treatment, using diverse chemical or physical agents including antibiotics. However, some of these treatments have side effects that compromise patient adherence and drug safety and in the case of antibiotics, it has been reported C. acnes resistance to these molecules. Phage therapy is an alternative to treat antibiotic-resistant bacterial strains and have been recently proposed as an immunomodulatory therapy. Here, we explore this perspective about phage therapy for acne, considering the potential immunomodulatory role of phages. Methodology: Literature review was performed using four different databases (Europe PubMed Central-ePMC, Google Scholar, PubMed, and ScienceDirect). Articles were ordered and selected according to their year of publication, number of citations, and quartile of the publishing journal. Results: The use of lytic bacteriophages to control bacterial infections has proven its promising results, and anti-inflammatory effects have been found for some bacteriophages and phage therapy. These effects can be related to bacterial elimination or direct interaction with immune cells that result in the regulation of pro-inflammatory cytokines. Studies on C. acnes bacteriophages have investigated their lytic activity, genomic structure, and stability on different matrices. However, studies exploring the potential of immunomodulation of these bacteriophages are still scarce. Conclusions: C. acnes bacteriophages, as well as other phages, may have direct immunomodulatory effects that are yet to be fully elucidated. To our knowledge, to the date that this review was written, there are only two studies that investigate anti-inflammatory properties for C. acnes bacteriophages. In those studies, it has been evidenced reduction of pro-inflammatory response to C. acnes inoculation in mice after bacteriophage application. Nevertheless, these studies were conducted in mice, and the interaction with the immune response was not described. Phage therapy to treat acne can be a suitable therapeutic alternative to C. acnes control, which in turn can aid to restore the skin's balance of microbiota. By controlling C. acnes colonization, C. acnes bacteriophages can reduce inflammatory reactions triggered by this bacterium.


Asunto(s)
Acné Vulgar , Bacteriófagos , Terapia de Fagos , Ratones , Animales , Acné Vulgar/terapia , Piel/microbiología , Bacteriófagos/genética , Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico
14.
Am J Bot ; 109(9): 1394-1409, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36031775

RESUMEN

PREMISE: Although ecological differentiation driven by altitude and soil is hypothesized to promote coexistence of sympatric tree species of Damburneya (Lauraceae), the mechanistic role of leaf functional variation on ecological differentiation among co-occurring species remains unexplored. We aimed to determine whether the patterns of leaf trait variation reflect ecological differences among sympatric Damburneya species. We tested whether trait correlations underlying functional strategies and average species traits vary in response to local soil heterogeneity along an altitudinal gradient, potentially affecting species distributions. METHODS: At two contrasting altitudes (100, 1100 m a.s.l.) in a Mexican tropical rainforest, we characterized soil chemical and physical properties and sampled four Damburneya species to quantify five leaf functional traits. We used linear models to analyze paired and multivariate trait correlations, spatial and interspecific effects on trait variation, and trait response to local soil heterogeneity. Relative contributions of intra- and interspecific variation to local trait variability were quantified with an ANOVA. RESULTS: Soil nutrient availability was higher at low altitude, but all species had a high leaf N:P ratio across altitudes suggesting a limited P supply for plants. Species distribution differed altitudinally, with some species constrained to low or high altitude, potentially reflecting soil nutrient availability. Leaf traits responded to altitude and local soil properties, suggesting interspecific differences in functional strategies according to the leaf economics spectrum (conservative vs. acquisitive). CONCLUSIONS: The interspecific divergence in functional strategies in response to local environmental conditions suggests that trait variation could underlie ecological differentiation among Damburneya sympatric species.


PREMISA: Aunque se ha propuesto que la diferenciación ecológica impulsada por la variación del suelo y la altitud ha promovido la coexistencia de especies arbóreas simpátricas de Damburneya (Lauraceae), el papel de la variación de funcional foliar como mecanismo para explicar las diferencias ecológicas entre especies que coocurren sigue sin explorarse. Nuestro objetivo fue determinar si los patrones de variación de los rasgos funcionales foliares reflejan diferencias ecológicas entre especies simpátricas de Damburneya. Hipotetizamos que, tanto las correlaciones entre los rasgos que determinan las estrategias funcionales, como los valores promedio de los rasgos de las especies, varían en respuesta a la heterogeneidad local del suelo a lo largo de un gradiente altitudinal, afectando potencialmente la distribución de las especies. MÉTODO: En dos altitudes contrastantes (100, 1000 m s.n.m) en una selva húmeda tropical mexicana caracterizamos propiedades físicas y químicas del suelo y muestreamos cuatro especies de Damburneya para cuantificar cinco rasgos funcionales foliares. Usamos modelos lineales para analizar las correlaciones pareadas y multivariadas entre rasgos, los efectos espaciales e interespecíficos en la variación de rasgos, y la respuesta de los rasgos a la heterogeneidad local del suelo. Además, cuantificamos la contribución relativa de la variación intra- e interespecífica en la varianza local de los rasgos con un análisis de varianza. RESULTADOS: La disponibilidad de nutrientes en el suelo fue mayor en la zona baja, pero todas las especies tuvieron valores altos de N:P foliar en ambas altitudes, lo que sugiere un suministro limitado de P para las plantas. La distribución de las especies difirió altitudinalmente y algunas de ellas se restringieron a zonas altas o bajas, reflejando potencialmente la disponibilidad de nutrientes en el suelo. Los rasgos foliares respondieron a la altitud y a las propiedades edáficas locales, sugiriendo diferencias interespecíficas en las estrategias funcionales según el espectro de economía foliar (conservativa vs. adquisitiva). CONCLUSIONES: La divergencia interespecífica en las estrategias funcionales en respuesta a las condiciones ambientales locales sugiere que la variación de rasgos podría explicar algunas diferencias ecológicas entre las especies simpátricas de Damburneya.


Asunto(s)
Lauraceae , Árboles , Hojas de la Planta/fisiología , Bosque Lluvioso , Suelo/química , Simpatría , Árboles/fisiología
15.
Am J Bot ; 108(9): 1793-1807, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34519027

RESUMEN

PREMISE: The mechanisms generating the geographical distributions of genetic diversity are a central theme in evolutionary biology. The amount of genetic diversity and its distribution are controlled by several factors, including dispersal abilities, physical barriers, and environmental and climatic changes. We investigated the patterns of genetic diversity and differentiation among populations of the widespread species Brosimum alicastrum in Mexico. METHODS: Using nuclear DNA microsatellite data, we tested whether the genetic structure of B. alicastrum was associated with the roles of the Trans-Mexican Volcanic Belt and the Isthmus of Tehuantepec as geographical barriers to gene flow and to infer the role of past events in the genetic diversity patterns. We further used a maximum-likelihood population-effects mixed model (MLPE) to identify the main factor affecting population differentiation in B. alicastrum. RESULTS: Our results suggested that Mexican B. alicastrum is well differentiated into three main lineages. Patterns of the genetic structure at a finer scale did not fully correspond to the current geographical barriers to gene flow. According to the MLPE mixed model, isolation by distance is the best model for explaining the genetic differentiation of B. alicastrum in Mexico. CONCLUSIONS: We propose that the differentiation patterns might reflect (1) an ancient differentiation that occurred in Central and South America, (2) the effects of past climatic changes, and (3) the functions of some physical barriers to gene flow. This study provides insights into the possible mechanisms underlying the geographic genetic variation of B. alicastrum along a moisture gradient in tropical lowland forests.


Asunto(s)
Variación Genética , Moraceae , Flujo Génico , México , Repeticiones de Microsatélite/genética
16.
PeerJ ; 9: e11466, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34178440

RESUMEN

BACKGROUND: Plants have evolved physical-chemical defense to prevent/diminish damage by their enemies. Chemical defense involves the synthesis' pathways of specialized toxic, repellent, or anti-nutritive metabolites to herbivores. Molecular evolutionary studies have revealed the origin of new genes, acquisition and functional diversification along time in different plant lineages. METHODS: Using bioinformatic tools we analyze gene divergence of tropane alkaloids (TAs) and terpene synthases (TPSs) in Datura stramonium and other species of Solanaceae; compared gene and amino acids sequence of TAs and TPSs on genomes, cDNA and proteins sequences of Viridiplantae. We analyzed two recently assembled genomes of D. stramonium (Ticumán and Teotihuacán), transcriptomes of Datura metel and genomes of other Solanaceae. Hence, we analyzed variation of TAs and TPSs to infer genes involved in plant defense and plant responses before stress. We analyzed protein modeling and molecular docking to predict interactions between H6H and ligand; we translated the sequences (Teo19488, Tic8550 and Tic8549) obtained from the two genomes of D. stramonium by using Swiss-Model and Ramachandran plot and MolProbity structure validation of Teo19488 protein model. RESULTS: For TAs, we detected an expansion event in the tropinone reductase II (TRII) and the ratio synonymous/non-synonymous substitutions indicate positive selection. In contrast, a contraction event and negative selection was detected in tropinone reductase I (TRI). In Hy-oscyamine 6 b-hydroxylase (H6H), enzyme involved in the production of tropane alkaloids atropine and scopolamine, the synonymous/non-synonymous substitution ratio in its dominion indicates positive selection. For terpenes (TPS), we found 18 DsTPS in D. stramomiun and seven in D. metel; evolutionary analyses detected positive selection in TPS10.1 and TPS10.2 of D. stramonium and D. metel. Comparison of copies of TPSs in D. stramonium detected variation among them in the binding site. Duplication events and differentiation of TAs and TPSs of D. stramonium, as compared to other Solanaceae, suggest their possible involvement on adaptive evolution of defense to herbivores. Protein modeling and docking show that the three protein structures obtained of DsH6H from Teo19488, Tic-8550 and Tic8549 maintain the same interactions and the union site of 2OG-FeII_Oxy with the Hy-o ligand as in 6TTM of D. metel. CONCLUSION: Our results indicate differences in the number of gene copies involved in the synthesis of tropane alkaloids, between the genomes of D. stramonium from two Mexican populations. More copies of genes related to the synthesis of tropane alkaloids (TRI, TRII, H6H, PMT) are found in D. stramonium as compared to Viridiplantae. Likewise, for terpene synthases (TPS), TPS-10 is duplicated in D. stramonium and D. metel. Further studies should be directed to experimentally assess gain (overexpression) or loss (silencing) of function of duplicated genes.

17.
PeerJ ; 9: e10698, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33777507

RESUMEN

Plant mating system determines, to a great extent, the demographic and genetic properties of populations, hence their potential for adaptive evolution. Variation in plant mating system has been documented between phylogenetically related species as well between populations of a species. A common evolutionary transition, from outcrossing to selfing, is likely to occur under environmental spatial variation in the service of pollinators. Here, we studied two phenotypically (in floral traits) and genetically (in neutral molecular markers) differentiated populations of the annual, insect-pollinated, plant Datura inoxia in Mexico, that differ in the service of pollinators (Mapimí and Cañada Moreno). First, we determined the populations' parameters of phenotypic in herkogamy, outcrossing and selfing rates with microsatellite loci, and assessed between generation (adults and seedlings) inbreeding, and inbreeding depression. Second, we compared the relationships between parameters in each population. Results point strong differences between populations: plants in Mapimí have, on average, approach herkogamy, higher outcrossing rate (t m = 0.68), lower primary selfing rate (r = 0.35), and lower inbreeding at equilibrium (F e = 0.24) and higher inbreeding depression (δ = 0.25), than the populations of Cañada. Outcrossing seems to be favored in Mapimí while selfing in Cañada. The relationship between r and F e were negatively associated with herkogamy in Mapimí; here, progenies derived from plants with no herkogamy or reverse herkogamy had higher selfing rate and inbreeding coefficient than plants with approach herkogamy. The difference F e-F is positively related to primary selfing rate (r) only in Cañada Moreno which suggests inbreeding depression in selfing individuals and then genetic purging. In conclusion, mating system evolution may occur differentially among maternal lineages within populations of Datura inoxia, in which approach herkogamy favors higher outcrossing rates and low levels of inbreeding and inbreeding depression, while no herkogamy or reverse herkogamy lead to the evolution of the "selfing syndrome" following the purge of deleterious alleles despite high inbreeding among individuals.

18.
Glob Health Promot ; 28(3): 50-58, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33506721

RESUMEN

INTRODUCTION: Indigenous peoples' food systems have weakened as a result of pressures exerted by agro-commercial policies and chains, which has led to the dependency and deterioration of their ways of life. It is in this context that the construction of perspectives on food autonomy positions itself as a potential and strategic field of social decolonial mobilization for indigenous peoples' health and buen vivir. OBJECTIVE: The aim of this study was to analyze the meanings of food autonomy from the perspectives of a Nasa Indigenous community in Colombia. METHOD: This was a qualitative study, involving 38 Indigenous people belonging to the Nasa Huila Indigenous community, aged between 18 and 73, with different occupations. The information was obtained by means of discussion groups and processed through content analysis. The project had the consent and ethical endorsement of the indigenous community. RESULTS: According to the study group, food autonomy is related to the Nasa identity, today weakened by territorial conditions, proximity to non-indigenous populations and the external influence of institutional food programs. Food autonomy develops by means of practices aimed at the production, distribution, preparation and consumption of healthy, chemical-free, homegrown food products from the family level, for self-consumption and in resistance to dependence on external commercial chains. CONCLUSION: Food autonomy positions itself as a community and political strategy that integrates the strengthening of family gardens, the adaptation of a food program menu, education and governance towards the development of autonomous processes from a decolonial perspective, for the promotion of health and buen vivir.


Asunto(s)
Servicios de Salud del Indígena , Pueblos Indígenas , Adolescente , Adulto , Anciano , Colombia , Abastecimiento de Alimentos , Humanos , Persona de Mediana Edad , Grupos de Población , Adulto Joven
19.
Evolution ; 74(12): 2629-2643, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32935854

RESUMEN

Because most species are collections of genetically variable populations distributed to habitats differing in their abiotic/biotic environmental factors and community composition, the pattern and strength of natural selection imposed by species on each other's traits are also expected to be highly spatially variable. Here, we used genomic and quantitative genetic approaches to understand how spatially variable selection operates on the genetic basis of plant defenses to herbivores. To this end, an F2 progeny was generated by crossing Datura stramonium (Solanaceae) parents from two populations differing in their level of chemical defense. This F2 progeny was reciprocally transplanted into the parental plants' habitats and by measuring the identity by descent (IBD) relationship of each F2 plant to each parent, we were able to elucidate how spatially variable selection imposed by herbivores operated on the genetic background (IBD) of resistance to herbivory, promoting local adaptation. The results highlight that plants possessing the highest total alkaloid concentrations (sum of all alkaloid classes) were not the most well-defended or fit. Instead, specific alkaloids and their linked loci/alleles were favored by selection imposed by different herbivores. This has led to population differentiation in plant defenses and thus, to local adaptation driven by plant-herbivore interactions.


Asunto(s)
Adaptación Biológica/genética , Alcaloides/farmacología , Datura stramonium/genética , Herbivoria/efectos de los fármacos , Defensa de la Planta contra la Herbivoria/genética , Alcaloides/análisis , Alcaloides/genética , Animales , Escarabajos , Datura stramonium/química , Ecosistema , Aptitud Genética , México , Selección Genética
20.
Ecol Evol ; 9(18): 10176-10184, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31632642

RESUMEN

Theories of plant invasion based on enemy release in a new range assume that selection exerted by specialist herbivores on defence traits should be reduced, absent, or even selected against in the new environment. Here, we measured phenotypic selection on atropine and scopolamine concentration of Datura stramonium in eight native (Mexico) and 14 non-native (Spain) populations. Native populations produced between 20 and 40 times more alkaloid than non-native populations (atropine: 2.0171 vs. 0.0458 mg/g; scopolamine: 1.004 vs. 0.0488 mg/g, respectively). Selection on alkaloids was negative for atropine and positive for scopolamine concentration in both ranges. However, the effect sizes of selection gradients were only significant in the native range. Our results support the assumption that the reduction of plant defence in the absence of the plant's natural enemies in invasive ranges is driven by natural selection.

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