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1.
PLoS Biol ; 22(1): e3002486, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38236896

RESUMEN

Acute gastrointestinal infection with intracellular pathogens like Salmonella Typhimurium triggers the release of the proinflammatory cytokine interleukin 1ß (IL-1ß). However, the role of IL-1ß in intestinal defense against Salmonella remains unclear. Here, we show that IL-1ß production is detrimental during Salmonella infection. Mice lacking IL-1ß (IL-1ß -/-) failed to recruit neutrophils to the gut during infection, which reduced tissue damage and prevented depletion of short-chain fatty acid (SCFA)-producing commensals. Changes in epithelial cell metabolism that typically support pathogen expansion, such as switching energy production from fatty acid oxidation to fermentation, were absent in infected IL-1ß -/- mice which inhibited Salmonella expansion. Additionally, we found that IL-1ß induces expression of complement anaphylatoxins and suppresses the complement-inactivator carboxypeptidase N (CPN1). Disrupting this process via IL-1ß loss prevented mortality in Salmonella-infected IL-1ß -/- mice. Finally, we found that IL-1ß expression correlates with expression of the complement receptor in patients suffering from sepsis, but not uninfected patients and healthy individuals. Thus, Salmonella exploits IL-1ß signaling to outcompete commensal microbes and establish gut colonization. Moreover, our findings identify the intersection of IL-1ß signaling and the complement system as key host factors involved in controlling mortality during invasive Salmonellosis.


Asunto(s)
Interleucina-1beta , Infecciones por Salmonella , Animales , Humanos , Ratones , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Neutrófilos/metabolismo , Infecciones por Salmonella/metabolismo , Salmonella typhimurium/metabolismo , Virulencia
2.
Syst Biol ; 72(2): 249-263, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35583314

RESUMEN

Oenothera sect. Calylophus is a North American group of 13 recognized taxa in the evening primrose family (Onagraceae) with an evolutionary history that may include independent origins of bee pollination, edaphic endemism, and permanent translocation heterozygosity. Like other groups that radiated relatively recently and rapidly, taxon boundaries within Oenothera sect. Calylophus have remained challenging to circumscribe. In this study, we used target enrichment, flanking noncoding regions, gene tree/species tree methods, tests for gene flow modified for target-enrichment data, and morphometric analysis to reconstruct phylogenetic hypotheses, evaluate current taxon circumscriptions, and examine character evolution in Oenothera sect. Calylophus. Because sect. Calylophus comprises a clade with a relatively restricted geographic range, we were able to extensively sample across the range of geographic, edaphic, and morphological diversity in the group. We found that the combination of exons and flanking noncoding regions led to improved support for species relationships. We reconstructed potential hybrid origins of some accessions and note that if processes such as hybridization are not taken into account, the number of inferred evolutionary transitions may be artificially inflated. We recovered strong evidence for multiple evolutionary origins of bee pollination from ancestral hawkmoth pollination, edaphic specialization on gypsum, and permanent translocation heterozygosity. This study applies newly emerging techniques alongside dense infraspecific sampling and morphological analyses to effectively reconstruct the recalcitrant history of a rapid radiation. [Gypsum endemism; Oenothera sect. Calylophus; Onagraceae; phylogenomics; pollinator shift; recent radiation; target enrichment.].


Asunto(s)
Oenothera , Animales , Filogenia , Oenothera/genética , Sulfato de Calcio , Polinización
3.
Dev Psychopathol ; : 1-9, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38415403

RESUMEN

Dante Cicchetti's remarkable contributions to the field of developmental psychopathology include the advancement of key principles such as the interplay of typical and atypical development, multifinality and equifinality, the dynamic processes of resilience, and the integration of multiple levels of analysis into developmental theories. In this paper we assert that person-centered data analytic methods are particularly well-suited to advancing these tenets of developmental psychopathology. We illustrate their utility with a brief novel empirical study focused on underlying patterns of childhood neuroendocrine regulation and prospective links with emerging adult functioning. Results indicate that a childhood neuroendocrine profile marked by high diurnal cortisol paired with low diurnal DHEA was uniquely associated with more adaptive functioning in emerging adulthood. We discuss these findings, and person-centered methods more broadly, within the future of developmental psychopathology.

4.
Psychol Med ; 53(7): 2974-2981, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37449490

RESUMEN

BACKGROUND: Although the prevalence rates of preadolescent eating disorders (EDs) are on the rise, considerably less is known about the correlates and treatment of EDs in this age group. Clarifying the epidemiology of EDs in preadolescent children is a necessary first step to understand the nature and scope of this problem in this age group. METHODS: Analysis of data collected in the ABCD Study release 2.0.1. The ABCD cohort was a population-based sample that consisted of 11 721 children ages 9-10 years. Measures included reports of a lifetime and current mental disorders determined using a diagnostic interview for DSM-5 disorders, sociodemographic factors, and psychiatric treatment utilization. RESULTS: The lifetime prevalence of EDs was 0.95%. Being Black, multiracial, having unmarried parents, and family economic insecurity were significant predictors for developing an ED. Among psychiatric conditions, the major depressive disorder was most robustly associated with EDs in both cross-sectional and temporal analyses. Only 47.40% of children who had a lifetime ED received some type of psychiatric treatment. EDs were not a significant predictor of psychiatric treatment utilization after accounting for sex, sexual orientation, parent marital status, economic insecurity, and all other psychiatric diagnoses. CONCLUSIONS: Despite increasing prevalence rates of preadolescent EDs, the current findings suggest that the majority of children with these disorders remain untreated. Devoting increased attention and resources to reaching families of children with EDs with the least means for receiving care, and screening for EDs in children with depression, may be important steps for reducing this unmet need.


Asunto(s)
Trastorno Depresivo Mayor , Trastornos de Alimentación y de la Ingestión de Alimentos , Humanos , Masculino , Niño , Femenino , Prevalencia , Estudios Transversales , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Psicoterapia
5.
Am J Bot ; 110(2): e16133, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36706341

RESUMEN

PREMISE: Whole-genome duplication is considered a major mechanism of sympatric speciation due to the creation of strong and instantaneous reproductive barriers. Although postzygotic reproductive isolation between diploids and polyploids is often expected, the extent of reproductive incompatibility must be empirically determined and compared to patterns of genetic isolation to fully characterize the reproductive dynamics between cytotypes. METHODS: We investigated reproductive compatibility between diploid and tetraploid Lycium australe in two mixed-cytotype populations using (1) controlled crossing experiments to evaluate fruit and seed production and (2) germination trials to test seed viability following homoploid and heteroploid crosses. We contrast these experiments with a single-nucleotide polymorphism (SNP) data set to measure genetic isolation between cytotypes and explore whether cytotype or population origin better explains patterns of genetic variation. Finally, we explore mating patterns using the observed germination rates of naturally produced seeds in each population. RESULTS: Although homoploid and heteroploid crosses resulted in similar fruit and seed production, reproductive isolation between co-occurring diploids and tetraploids was nearly complete, due to low seed viability following heteroploid crosses. Of 191,182 total SNPs, 21,679 were present in ≥90% of individuals and replicate runs using unlinked SNPs revealed strong clustering by cytotype and differentiation of tetraploids based on population origin. CONCLUSIONS: As often reported, diploid and tetraploid L. australe experience strong postzygotic isolation via hybrid seed inviability. Consistent with this result, cytotype explained a greater amount of variation in the SNP data set than population origin, despite some evidence of historical introgression.


Asunto(s)
Diploidia , Lycium , Tetraploidía , Aislamiento Reproductivo , Poliploidía
6.
J Am Soc Nephrol ; 33(9): 1677-1693, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35961788

RESUMEN

BACKGROUND: Secondary hyperparathyroidism (SHP) is a common complication of CKD that increases morbidity and mortality. In experimental SHP, increased parathyroid hormone (PTH) expression is due to enhanced PTH mRNA stability, mediated by changes in its interaction with stabilizing AUF1 and destabilizing KSRP. The isomerase Pin1 leads to KSRP dephosphorylation, but in SHP parathyroid Pin1 activity is decreased and hence phosphorylated KSRP fails to bind PTH mRNA, resulting in high PTH mRNA stability and levels. The up- and downstream mechanisms by which CKD stimulates the parathyroid glands remain elusive. METHODS: Adenine-rich high-phosphate diets induced CKD in rats and mice. Parathyroid organ cultures and transfected cells were incubated with Pin1 inhibitors for their effect on PTH expression. Mass spectrometry was performed on both parathyroid and PTH mRNA pulled-down proteins. RESULTS: CKD led to changes in rat parathyroid proteome and phosphoproteome profiles, including KSRP phosphorylation at Pin1 target sites. Furthermore, both acute and chronic kidney failure led to parathyroid-specific Pin1 Ser16 and Ser71 phosphorylation, which disrupts Pin1 activity. Pharmacologic Pin1 inhibition, which mimics the decreased Pin1 activity in SHP, increased PTH expression ex vivo in parathyroid glands in culture and in transfected cells through the PTH mRNA-protein interaction element and KSRP phosphorylation. CONCLUSIONS: Kidney failure leads to loss of parathyroid Pin1 activity by inducing Pin1 phosphorylation. This predisposes parathyroids to increase PTH production through impaired PTH mRNA decay that is dependent on KSRP phosphorylation at Pin1-target motifs. Pin1 and KSRP phosphorylation and the Pin1-KSRP-PTH mRNA axis thus drive SHP.


Asunto(s)
Hiperparatiroidismo Secundario , Fallo Renal Crónico , Insuficiencia Renal , Ratas , Ratones , Animales , Glándulas Paratiroides/metabolismo , ARN Mensajero/metabolismo , Fosforilación , Hiperparatiroidismo Secundario/etiología , Hormona Paratiroidea , Fallo Renal Crónico/complicaciones , Insuficiencia Renal/complicaciones
7.
BMC Genomics ; 23(1): 124, 2022 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-35151274

RESUMEN

BACKGROUND: Plant volatiles play an important role in both plant-pollinator and plant-herbivore interactions. Intraspecific polymorphisms in volatile production are ubiquitous, but studies that explore underlying differential gene expression are rare. Oenothera harringtonii populations are polymorphic in floral emission of the monoterpene (R)-(-)-linalool; some plants emit (R)-(-)-linalool (linalool+ plants) while others do not (linalool- plants). However, the genes associated with differential production of this floral volatile in Oenothera are unknown. We used RNA-Seq to broadly characterize differential gene expression involved in (R)-(-)-linalool biosynthesis. To identify genes that may be associated with the polymorphism for this trait, we used RNA-Seq to compare gene expression in six different Oenothera harringtonii tissues from each of three linalool+ and linalool- plants. RESULTS: Three clusters of differentially expressed genes were enriched for terpene synthase activity: two were characterized by tissue-specific upregulation and one by upregulation only in plants with flowers that produce (R)-(-)-linalool. A molecular phylogeny of all terpene synthases identified two putative (R)-(-)-linalool synthase transcripts in Oenothera harringtonii, a single allele of which is found exclusively in linalool+ plants. CONCLUSIONS: By using a naturally occurring polymorphism and comparing different tissues, we were able to identify candidate genes putatively involved in the biosynthesis of (R)-(-)-linalool. Expression of these genes in linalool- plants, while low, suggests a regulatory polymorphism, rather than a population-specific loss-of-function allele. Additional terpene biosynthesis-related genes that are up-regulated in plants that emit (R)-(-)-linalool may be associated with herbivore defense, suggesting a potential economy of scale between plant reproduction and defense.


Asunto(s)
Oenothera biennis , Oenothera , Onagraceae , Flores/genética , Expresión Génica , Regulación de la Expresión Génica de las Plantas , Odorantes
8.
Proc Biol Sci ; 289(1978): 20220589, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35858051

RESUMEN

The study of song development has focused on temperate zone birds in which typically only males sing. In the bay wren, Cantorchilus nigricapillus, both sexes sing, performing precisely timed, female-initiated duets in which birds alternate sex-specific song phrases. We investigated the development of these sex differences by collecting bay wren eggs and nestlings, and hand-raising them in individual acoustic isolation chambers. Each bird was tutored with either monophonic or stereophonic recordings of bay wren duets or heard no song. As adults, each tutored bird sang repertoires of complete duets, singing both male and female phrases. In addition, some birds sang only the male or female part of some duets to which they were exposed. Mono-tutored birds showed no sex-specificity in these solo songs, whereas stereo-tutored birds only sang solos consistent with their sex. In addition, stereo-tutored birds acquired songs over a longer period than did mono-tutored birds, and stereo-tutored females showed more sex-specificity than did males during early song production. Finally, we observed that tutored and acoustically isolated birds of both sexes invented male-like songs, whereas only males invent songs in the wild. These results reveal the relative roles of environmental versus innate influences in the development of sex-specific song in this species.


Asunto(s)
Pájaros Cantores , Animales , Femenino , Aprendizaje , Masculino , Caracteres Sexuales , Vocalización Animal
9.
Am J Bot ; 108(4): 694-710, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33811320

RESUMEN

PREMISE: Long-distance dispersal has been important in explaining the present distributions of many plant species. Despite being infrequent, such dispersal events have considerable evolutionary consequences, because bottlenecks during colonization can result in reduced genetic diversity. We examined the phylogeographic history of Lycium carolinianum, a widespread taxon that ranges from southeastern North America to several Pacific islands, with intraspecific diversity in sexual and mating systems. METHODS: We used Bayesian, likelihood, and coalescent approaches with nuclear and plastid sequence data and genome-wide single nucleotide polymorphisms to reconstruct the dispersal history of this species. We also compared patterns of genetic variation in mainland and island populations using single nucleotide polymorphisms and allelic diversity at the S-RNase mating system gene. RESULTS: Lycium carolinianum is monophyletic and dispersed once from the North American mainland, colonizing the Pacific islands ca. 40,100 years ago. This dispersal was accompanied by a loss of genetic diversity in SNPs and the S-RNase locus due to a colonization bottleneck and the loss of self-incompatibility. Additionally, we documented at least two independent transitions to gynodioecy: once following the colonization of the Hawaiian Islands and loss of self-incompatibility, and a second time associated with polyploidy in the Yucatán region of Mexico. CONCLUSIONS: Long-distance dispersal via fleshy, bird dispersed fruits best explains the unusually widespread distribution of L. carolinianum. The collapse of diversity at the S-RNase locus in island populations suggests that self-fertilization may have facilitated the subsequent colonization of Pacific islands following a single dispersal from mainland North America.


Asunto(s)
Lycium , Teorema de Bayes , Hawaii , Islas , Lycium/genética , México , América del Norte , Islas del Pacífico , Filogenia
10.
Mol Ecol ; 29(9): 1684-1703, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32268445

RESUMEN

Small increases in ocean temperature can disrupt the obligate symbiosis between corals and dinoflagellate microalgae, resulting in coral bleaching. Little is known about the genes that drive the physiological and bleaching response of algal symbionts to elevated temperature. Moreover, many studies to-date have compared highly divergent strains, making it challenging to accredit specific genes to contrasting traits. Here, we compare transcriptional responses at ambient (27°C) and bleaching-relevant (31°C) temperatures in a monoclonal, wild-type (WT) strain of Symbiodiniaceae to those of a selected-strain (SS), derived from the same monoclonal culture and experimentally evolved to elevated temperature over 80 generations (2.5 years). Thousands of genes were differentially expressed at a log fold-change of >8 between the WT and SS over a 35 days temperature treatment period. At 31°C, WT cells exhibited a temporally unstable transcriptomic response upregulating genes involved in the universal stress response such as molecular chaperoning, protein repair, protein degradation and DNA repair. Comparatively, SS cells exhibited a temporally stable transcriptomic response and downregulated many stress response genes that were upregulated by the WT. Among the most highly upregulated genes in the SS at 31°C were algal transcription factors and a gene probably of bacterial origin that encodes a type II secretion system protein, suggesting interactions with bacteria may contribute to the increased thermal tolerance of the SS. Genes and functional pathways conferring thermal tolerance in the SS could be targeted in future genetic engineering experiments designed to develop thermally resilient algal symbionts for use in coral restoration and conservation.


Asunto(s)
Antozoos , Dinoflagelados , Estrés Fisiológico , Simbiosis , Temperatura , Adaptación Fisiológica/genética , Animales , Antozoos/genética , Arrecifes de Coral , Dinoflagelados/genética , Evolución Molecular , Laboratorios , Microalgas/genética
12.
Am J Bot ; 106(5): 733-743, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31042317

RESUMEN

PREMISE: As Baker's law suggests, the successful colonization of oceanic islands is often associated with uniparental reproduction (self-fertility), but the high incidence of dimorphism (dioecy, gynodioecy) on islands complicates this idea. Lycium carolinianum is widespread, occurring on the North American mainland and the Hawaiian Islands. We examined Baker's ideas for mainland and island populations of L. carolinianum and examined inbreeding depression as a possible contributor to the evolution of gynodioecy on Maui. METHODS: Controlled crosses were conducted in two mainland populations and two populations in Hawaii. Treatments included self and cross pollination, unmanipulated controls, and autogamy/agamospermy. Alleles from the self-incompatibility S-RNase gene were isolated and compared between mainland and island populations. Given self-compatibility in Hawaii, we germinated seeds from self- and cross- treatments and estimated inbreeding depression using seven traits and a measure of cumulative fitness. RESULTS: Mainland populations of Lycium carolinianum are predominately self-incompatible with some polymorphism for self-fertility, whereas Hawaiian populations are self-compatible. Concordantly, S-RNase allelic diversity is reduced in Hawaii compared to the mainland. Hawaiian populations also exhibit significant inbreeding depression. CONCLUSIONS: Self-compatibility in Hawaii and individual variation in self-fertility in mainland populations suggests that a colonization filter promoting uniparental reproduction may be acting in this system. Comparison of S-RNase variation suggests a collapse of allelic diversity and heterozygosity at the S-RNase locus in Hawaii, which likely contributed to mate limitation upon arrival to the Pacific. Inbreeding depression coupled with autonomous self-fertilization may have led to the evolution of gynodioecy on Maui.


Asunto(s)
Evolución Biológica , Lycium/fisiología , Dispersión de las Plantas , Hawaii , Especies Introducidas , Islas , Reproducción
13.
Mol Biol Evol ; 33(9): 2201-15, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27301593

RESUMEN

Corals rely on photosynthesis by their endosymbiotic dinoflagellates (Symbiodinium spp.) to form the basis of tropical coral reefs. High sea surface temperatures driven by climate change can trigger the loss of Symbiodinium from corals (coral bleaching), leading to declines in coral health. Different putative species (genetically distinct types) as well as conspecific populations of Symbiodinium can confer differing levels of thermal tolerance to their coral host, but the genes that govern dinoflagellate thermal tolerance are unknown. Here we show physiological and transcriptional responses to heat stress by a thermo-sensitive (physiologically susceptible at 32 °C) type C1 Symbiodinium population and a thermo-tolerant (physiologically healthy at 32 °C) type C1 Symbiodinium population. After nine days at 32 °C, neither population exhibited physiological stress, but both displayed up-regulation of meiosis genes by ≥ 4-fold and enrichment of meiosis functional gene groups, which promote adaptation. After 13 days at 32 °C, the thermo-sensitive population suffered a significant decrease in photosynthetic efficiency and increase in reactive oxygen species (ROS) leakage from its cells, whereas the thermo-tolerant population showed no signs of physiological stress. Correspondingly, only the thermo-tolerant population demonstrated up-regulation of a range of ROS scavenging and molecular chaperone genes by ≥ 4-fold and enrichment of ROS scavenging and protein-folding functional gene groups. The physiological and transcriptional responses of the Symbiodinium populations to heat stress directly correlate with the bleaching susceptibilities of corals that harbored these same Symbiodinium populations. Thus, our study provides novel, foundational insights into the molecular basis of dinoflagellate thermal tolerance and coral bleaching.


Asunto(s)
Antozoos/genética , Dinoflagelados/genética , Aclimatación/genética , Adaptación Fisiológica/genética , Animales , Antozoos/metabolismo , Cambio Climático , Arrecifes de Coral , Dinoflagelados/metabolismo , Calor , Chaperonas Moleculares/genética , Fotosíntesis/genética , Estrés Fisiológico/genética , Simbiosis , Transcriptoma
14.
J Eukaryot Microbiol ; 64(5): 588-597, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28120360

RESUMEN

Dinoflagellates within the genus Symbiodinium are photosymbionts of many tropical reef invertebrates, including corals, making them central to the health of coral reefs. Symbiodinium have therefore gained significant research attention, though studies have been constrained by technical limitations. In particular, the generation of viable cells with their cell walls removed (termed protoplasts) has enabled a wide range of experimental techniques for bacteria, fungi, plants, and algae such as ultrastructure studies, virus infection studies, patch clamping, genetic transformation, and protoplast fusion. However, previous studies have struggled to remove the cell walls from armored dinoflagellates, potentially due to the internal placement of their cell walls. Here, we produce the first Symbiodinium protoplasts from three genetically and physiologically distinct strains via incubation with cellulase and osmotic agents. Digestion of the cell walls was verified by a lack of Calcofluor White fluorescence signal and by cell swelling in hypotonic culture medium. Fused protoplasts were also observed, motivating future investigation into intra- and inter-specific somatic hybridization of Symbiodinium. Following digestion and transfer to regeneration medium, protoplasts remained photosynthetically active, regrew cell walls, regained motility, and entered exponential growth. Generation of Symbiodinium protoplasts opens exciting, new avenues for researching these crucial symbiotic dinoflagellates, including genetic modification.


Asunto(s)
Celulasa/metabolismo , Dinoflagelados/ultraestructura , Protoplastos/ultraestructura , Pared Celular/metabolismo , Arrecifes de Coral , Protoplastos/metabolismo , Simbiosis
15.
Am J Bot ; 104(3): 451-460, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28298376

RESUMEN

PREMISE OF THE STUDY: Floral morphology is expected to evolve following the transition from cosexuality to gender dimorphism in plants, as selection through male and female function becomes dissociated. Specifically, male-biased dimorphism in flower size can arise through selection for larger flowers through male function, selection for smaller flowers through female function, or both. The evolutionary pathway to floral dimorphism can be most effectively reconstructed in species with intraspecific variation in sexual system. We examined the evolution of flower size and shape in Lycium californicum, whose populations are either gender dimorphic with male and female plants, or cosexual with hermaphroditic plants. METHODS: Floral morphology was characterized in populations spanning the species' complete range. For a subset of the range where cosexual and dimorphic populations are in close proximity, we compared the size and shape of flowers from female and male plants in dimorphic populations to hermaphrodites in cosexual populations, accounting for variation associated with abiotic environmental conditions. KEY RESULTS: The magnitude of flower size dimorphism varied across dimorphic populations. After controlling for environmental variation across cosexual and dimorphic populations, flowers on males were larger than flowers on females and hermaphrodites, whereas flower size did not differ between females and hermaphrodites. Flower shape differences were associated with mating type, sexual system, and environmental variation. CONCLUSIONS: While abiotic environmental gradients shape both overall flower size and shape, male-biased flower size dimorphism in L. californicum appears to arise through selection for larger flowers in males but not smaller flowers in females.


Asunto(s)
Flores/genética , Lycium/genética , Evolución Biológica , Ambiente , Flores/anatomía & histología , Flores/crecimiento & desarrollo , Flores/fisiología , Geografía , Lycium/anatomía & histología , Lycium/crecimiento & desarrollo , Lycium/fisiología , Infertilidad Vegetal , Reproducción , Caracteres Sexuales , Especificidad de la Especie
16.
Ann Bot ; 117(2): 307-17, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26546375

RESUMEN

BACKGROUND AND AIMS: Polyploidy has important effects on reproductive systems in plants and has been implicated in the evolution of dimorphic sexual systems. In particular, higher ploidy is associated with gender dimorphism across Lycium species (Solanaceae) and across populations within the species Lycium californicum. Previous research on the association of cytotype and sexual system within L. californicum sampled a limited portion of the species range, and did not investigate evolutionary transitions between sexual systems. Lycium californicum occurs in arid regions on offshore islands and mainland regions in the south-western United States and Mexico, motivating a more comprehensive analysis of intraspecific variation in sexual system and cytotype across the full range of this species. METHODS: Sexual system (dimorphic vs. cosexual) was determined for 34 populations across the geographical range of L. californicum using field observations of pollen production, and was confirmed using morphological measurements and among-plant correlations of primary sexual traits. Ploidy was inferred using flow cytometry in 28 populations. DNA sequence data from four plastid and two nuclear regions were used to reconstruct relationships among populations and to map transitions in sexual system and ploidy. KEY RESULTS: Lycium californicum is monophyletic, ancestrally diploid and cosexual, and the association of gender dimorphism and polyploidy appears to have two evolutionary origins in this species. Compared with cosexual populations, dimorphic populations had bimodal anther size distributions, negative correlations between male and female floral traits, and larger coefficients of variation for primary sexual traits. Flow cytometry confirmed tetraploidy in dimorphic populations, whereas cosexual populations were diploid. CONCLUSIONS: Tetraploidy and gender dimorphism are perfectly correlated in L. californicum, and the distribution of tetraploid-dimorphic populations is restricted to populations in Arizona and the Baja California peninsula. The analysis suggests that tetraploidy and dimorphism likely established in Baja California and may have evolved multiple times.


Asunto(s)
Lycium/genética , Polimorfismo Genético , Reproducción/fisiología , Arizona , California , Cloroplastos/genética , Ecotipo , Genética de Población , Haplotipos , Lycium/fisiología , México , Filogenia , Poliploidía , Reproducción/genética
17.
Am J Bot ; 101(12): 2160-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25480712

RESUMEN

UNLABELLED: • PREMISE OF THE STUDY: An association between polyploidy and gender dimorphism has been noted in several plant lineages. Whereas the majority of Lycium species are diploid and have hermaphroditic flowers in cosexual populations, gender dimorphism (gynodioecy, dioecy) has been shown to be uniformly associated with polyploidy in previous studies. Preliminary field observations suggested that some populations of Lycium carolinianum were dimorphic, providing a test of this association.• METHODS: We assessed sexual systems and cytotype variation (to infer ploidy) across 17 populations of L. carolinianum. Comparison of flowers in cosexual and dimorphic populations were used to infer changes in reproductive morphology associated with the evolution of gynodioecy.• KEY RESULTS: The majority of populations were cosexual in gender expression, but dimorphism was present in the Yucatán and in some populations in Hawaii. Populations varied in ploidy and were either diploid or tetraploid. Floral sexual dimorphism was present in all gynodioecious populations, though the magnitude differed and was cryptic in some cases. Our results are consistent with the hypothesis that following the evolution of gynodioecy, flowers on hermaphrodites increased in size.• CONCLUSIONS: Dimorphic sexual systems have likely evolved convergently in L. carolinianum. In contrast to previous studies, dimorphism is not perfectly associated with polyploidy. Although our sample from the Yucatán was both tetraploid and dimorphic, all populations in Hawaii were diploid regardless of sexual system. Ongoing phylogeographic and mating system studies will contribute to our understanding of reproductive evolution in this widespread, polymorphic species.


Asunto(s)
Evolución Biológica , Flores/anatomía & histología , Variación Genética , Lycium/genética , Poliploidía , Hawaii , Lycium/anatomía & histología , Lycium/fisiología , México , Reproducción
18.
Transl Psychiatry ; 14(1): 152, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38503761

RESUMEN

Although posttraumatic stress disorder (PTSD) has been well characterized in adults, its epidemiology in children is unclear. The current study provides the first population-based examination of the prevalence of PTSD, sociodemographic and psychiatric correlates, clinical sequelae, and associations with psychiatric treatment in preadolescents 9-10 years old in the United States. Data from the Adolescent Brain and Cognitive Development (ABCD) Study (release 5.0) was analyzed. Participants (unweighted n = 11,875) were recruited from 21 sites across the United States. Current and lifetime PTSD prevalence were estimated, as was treatment use among children with PTSD. Sociodemographic, psychiatric correlates and sequelae of PTSD were analyzed using logistic regression, as was the association between PTSD and psychiatric treatment. After the application of propensity weights, lifetime prevalence of PTSD was 2.17%. Sexual minority status, being multiracial, having unmarried parents, and family economic insecurity were associated with greater odds of PTSD. Among psychiatric disorders, separation anxiety was most strongly associated with PTSD, although general comorbid psychopathology was associated with greater odds of PTSD. Prior history of PTSD predicted a new onset of other psychiatric disorders after PTSD remission. Nearly one in three children with lifetime PTSD did not receive psychiatric treatment, despite negative long-term outcomes of PTSD and significant psychiatric comorbidity. Even among preadolescents who experience full remission of PTSD, a significant risk for future psychiatric illness remains. Further, the current findings underscore the need for improved efforts to reduce unmet treatment needs among those with PTSD at this age.


Asunto(s)
Trastornos por Estrés Postraumático , Adulto , Niño , Adolescente , Humanos , Estados Unidos/epidemiología , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/terapia , Trastornos por Estrés Postraumático/diagnóstico , Prevalencia , Comorbilidad , Psicopatología , Progresión de la Enfermedad
19.
Anim Microbiome ; 6(1): 19, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38650014

RESUMEN

BACKGROUND: A mother's milk is considered the gold standard of nutrition in neonates and is a source of cytokines, immunoglobulins, growth factors, and other important components, yet little is known about the components of canine milk, specifically colostrum, and the knowledge related to its microbial and metabolic profiles is particularly underwhelming. In this study, we characterized canine colostrum and milk microbiota and metabolome for several breeds of dogs and examined profile shifts as milk matures in the first 8 days post-whelping. RESULTS: Through untargeted metabolomics, we identified 63 named metabolites that were significantly differentially abundant between days 1 and 8 of lactation. Surprisingly, the microbial compositions of the colostrum and milk, characterized using 16S rRNA gene sequencing, were largely similar, with only two differentiating genera. The shifts observed, mainly increases in several sugars and amino sugars over time and shifts in amino acid metabolites, align with shifts observed in human milk samples and track with puppy development. CONCLUSION: Like human milk, canine milk composition is dynamic, and shifts are well correlated with developing puppies' needs. Such a study of the metabolic profile of canine milk, and its relation to the microbial community, provides insights into the changing needs of the neonate, as well as the ideal nutrition profile for optimal functionality. This information will add to the existing knowledge base of canine milk composition with the prospect of creating a quality, tailored milk substitute or supplement for puppies.

20.
Heliyon ; 10(8): e29324, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38628754

RESUMEN

Objective: This study aimed to assess the effect of increased omega-3 consumption on fertilization rates and the probability of women getting pregnant. This study is needed because different perspectives exist regarding the use of omega-3 fatty acids in enhancing fertility among women with reproductive issues, and information for those planning a spontaneous pregnancy is limited. Methods: PubMed, Clinical Trials, CINAHL/EBSCO, Medline Complete, Cochrane Library, and Google Scholar were searched for articles published until April 2021, and the search was limited to articles in English language. The search strategy included the following key words: "in-vitro fertilization (IVF)," "intracytoplasmic sperm injection techniques (ICSI)," "pregnancy," "omega-3 fatty acid," "alpha-linolenic acid," "eicosapentaenoic acid," "docosahexaenoic acid," "n-3 polyunsaturated fatty acid," and "fish oil and seafood." Studies reporting female fertility occurring naturally or IVF/ICSI concurrent with omega-3 intake were included. Retrospective studies, studies including postmenopausal women, and unevenly matched control and study groups were excluded. To assess bias, we used the Cochrane Handbook for Systematic Reviews of Interventions, version 5.1.0. To synthesize the findings from the studies included in this review, a meta-analysis was conducted using calculated or extracted odds ratios (OR) of clinical pregnancies and fertilization rates for each group in each study. Results: We included six trials involving 1789 women who received fertility treatment, four trials involving 2607 women who conceived naturally, and three trials involving 1725 oocytes for fertility rates. Aggregated ORs for the effects of omega-3 on pregnancies were 1.74, 1.36, and 2.14 for women who received fertility treatment, those who conceived naturally, and fertilization rate, respectively. All these results were significant (p ≤ 0.01), although they had high heterogeneity I2>68 %. Conclusion: This systematic review and meta-analysis suggest that omega-3 intake significantly improves women's pregnancy and fertilization rates; however, the high heterogeneity in this review somewhat limits its interpretation. Therefore, further prospective randomized studies are necessary to better understand this relationship.

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