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1.
Proc Natl Acad Sci U S A ; 119(34): e2122667119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35972961

RESUMEN

Field biology is an area of research that involves working directly with living organisms in situ through a practice known as "fieldwork." Conducting fieldwork often requires complex logistical planning within multiregional or multinational teams, interacting with local communities at field sites, and collaborative research led by one or a few of the core team members. However, existing power imbalances stemming from geopolitical history, discrimination, and professional position, among other factors, perpetuate inequities when conducting these research endeavors. After reflecting on our own research programs, we propose four general principles to guide equitable, inclusive, ethical, and safe practices in field biology: be collaborative, be respectful, be legal, and be safe. Although many biologists already structure their field programs around these principles or similar values, executing equitable research practices can prove challenging and requires careful consideration, especially by those in positions with relatively greater privilege. Based on experiences and input from a diverse group of global collaborators, we provide suggestions for action-oriented approaches to make field biology more equitable, with particular attention to how those with greater privilege can contribute. While we acknowledge that not all suggestions will be applicable to every institution or program, we hope that they will generate discussions and provide a baseline for training in proactive, equitable fieldwork practices.


Asunto(s)
Discusiones Bioéticas , Biología , Biología/ética , Humanos
2.
Mol Biol Evol ; 40(10)2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37791477

RESUMEN

Amphibians are ideal for studying visual system evolution because their biphasic (aquatic and terrestrial) life history and ecological diversity expose them to a broad range of visual conditions. Here, we evaluate signatures of selection on visual opsin genes across Neotropical anurans and focus on three diurnal clades that are well-known for the concurrence of conspicuous colors and chemical defense (i.e., aposematism): poison frogs (Dendrobatidae), Harlequin toads (Bufonidae: Atelopus), and pumpkin toadlets (Brachycephalidae: Brachycephalus). We found evidence of positive selection on 44 amino acid sites in LWS, SWS1, SWS2, and RH1 opsin genes, of which one in LWS and two in RH1 have been previously identified as spectral tuning sites in other vertebrates. Given that anurans have mostly nocturnal habits, the patterns of selection revealed new sites that might be important in spectral tuning for frogs, potentially for adaptation to diurnal habits and for color-based intraspecific communication. Furthermore, we provide evidence that SWS2, normally expressed in rod cells in frogs and some salamanders, has likely been lost in the ancestor of Dendrobatidae, suggesting that under low-light levels, dendrobatids have inferior wavelength discrimination compared to other frogs. This loss might follow the origin of diurnal activity in dendrobatids and could have implications for their behavior. Our analyses show that assessments of opsin diversification in across taxa could expand our understanding of the role of sensory system evolution in ecological adaptation.


Asunto(s)
Opsinas , Venenos , Animales , Opsinas/genética , Filogenia , Opsinas de Bastones/genética
3.
Proc Biol Sci ; 291(2020): 20232340, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38593845

RESUMEN

Studies of adaptive radiations have played a central role in our understanding of reproductive isolation. Yet the focus has been on human-biased visual and auditory signals, leaving gaps in our knowledge of other modalities. To date, studies on chemical signals in adaptive radiations have focused on systems with multimodal signalling, making it difficult to isolate the role chemicals play in reproductive isolation. In this study we examine the use of chemical signals in the species recognition and adaptive radiation of Hawaiian Tetragnatha spiders by focusing on entire communities of co-occurring species, and conducting behavioural assays in conjunction with chemical analysis of their silks using gas chromatography-mass spectrometry. Male spiders significantly preferred the silk extracts of conspecific mates over those of sympatric heterospecifics. The compounds found in the silk extracts, long chain alkyl methyl ethers, were remarkably species-specific in the combination and quantity. The differences in the profile were greatest between co-occurring species and between closely related sibling species. Lastly, there were significant differences in the chemical profile between two populations of a particular species. These findings provide key insights into the role chemical signals play in the attainment and maintenance of reproductive barriers between closely related co-occurring species.


Asunto(s)
Arañas , Animales , Humanos , Masculino , Hawaii , Especificidad de la Especie , Aislamiento Reproductivo , Seda
4.
Mol Phylogenet Evol ; 195: 108065, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38531492

RESUMEN

Poison frogs (Dendrobatidae) are famous for their aposematic species, having a combination of diverse color patterns and defensive skin toxins, yet most species in this family are inconspicuously colored and considered non-aposematic. Epipedobates is among the youngest genus-level clades of Dendrobatidae that includes both aposematic and inconspicuous species. Using Sanger-sequenced mitochondrial and nuclear markers, we demonstrate deep genetic divergences among inconspicuous species of Epipedobates but relatively shallow genetic divergences among conspicuous species. Our phylogenetic analysis includes broad geographic sampling of the inconspicuous lineages typically identified as E. boulengeri and E. espinosai, which reveals two putative new species, one in west-central Colombia (E. sp. 1) and the other in north-central Ecuador (E. aff. espinosai). We conclude that E. darwinwallacei is a junior subjective synonym of E. espinosai. We also clarify the geographic distributions of inconspicuous Epipedobates species including the widespread E. boulengeri. We provide a qualitative assessment of the phenotypic diversity in each nominal species, with a focus on the color and pattern of inconspicuous species. We conclude that Epipedobates contains eight known valid species, six of which are inconspicuous. A relaxed molecular clock analysis suggests that the most recent common ancestor of Epipedobates is âˆ¼11.1 million years old, which nearly doubles previous estimates. Last, genetic information points to a center of species diversity in the Chocó at the southwestern border of Colombia with Ecuador. A Spanish translation of this text is available in the supplementary materials.


Asunto(s)
Anuros , Ranas Venenosas , Animales , Filogenia , Anuros/genética , Mitocondrias , Ecuador
5.
J Evol Biol ; 37(2): 141-151, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38271116

RESUMEN

Secondary sexual traits can convey information on mate quality with the signal honesty maintained by the costly nature of trait expression. Mating signals are also often underpinned by physiological, morphological, and behavioural adaptations, which may require the evolution of novelty, but the genetic basis in many cases is unknown. In orchid bees, males acquire chemical compounds from the environment that act as pheromone-like bouquets (perfumes) during courtship displays. This process could be costly, potentially due to the cognitive demands of learning and the physiological demands of collecting a mix of extrinsic chemical compounds that may require detoxification. Furthermore, a novel trait, a specialized perfume pouch in the hind leg, is required for compound storage. We studied gene expression in the brain, hind leg, and Malpighian tubules-a tissue involved in detoxification-to investigate changes in gene expression following perfume collection. We detected upregulation of genes enriched in functions related to transcription, odorant binding, and receptor activity in the Malpighian tubules. On the other hand, we did not find any evidence for learning processes following perfume collection, or gene expression changes in the hind leg, perhaps due to constitutive expression, or the age of the sampled bees. We did identify high expression of chemosensory proteins in the hind legs, which we suggest could play a role in perfume collection or storage, with further functional studies necessary to determine their binding properties and potential physiological importance. Los rasgos sexuales secundarios pueden servir como indicadores de calidad de la pareja, y en algunos casos la honestidad de la señal se mantiene por el costo de expresar el rasgo. A menudo las señales sexuales están respaldadas por adaptaciones fisiológicas, morfológicas y de comportamiento por lo tanto pueden requerir la evolución de nuevos rasgos, pero en muchos casos se desconoce la base genética. En las abejas de las orquídeas, los machos recolectan compuestos químicos del medio ambiente, los cuales actúan como feromonas (perfumes) durante el despliegue de cortejo. Este proceso podría ser costoso, posiblemente debido a las demandas cognitivas del aprendizaje y las demandas fisiológicas de recolectar una mezcla de compuestos químicos extrínsecos que pueden requerir desintoxicación. Además, se requiere la evolución de un contenedor para almacenar perfumes en la pata trasera. Para investigar los cambios en la expresión génica después de la recolección de perfume, estudiamos la expresión génica en el cerebro, la pata trasera y los túbulos de Malpighi (tejido involucrado en la desintoxicación). Encontramos varios genes regulados positivamente en los túbulos de Malpighi después de la recolección que están enriquecidos en factores de transcripción, proteínas de fijación de olores, y proteínas con actividad de receptor. Por otro lado, no encontramos ninguna evidencia de procesos de aprendizaje posteriores a la recolección de perfumes, o cambios en la expresión génica en la pata trasera, esto quizás debido a la expresión constitutiva o la edad de las abejas muestreadas. Además, identificamos una alta expresión de proteínas quimio-sensoriales en las patas traseras, que podría desempeñar un papel en la recolección o almacenamiento de perfumes. Más estudios funcionales son necesarios para determinar las propiedades de fijación de las proteínas y su potencial importancia fisiológica.


Asunto(s)
Perfumes , Masculino , Abejas/genética , Animales , Transcriptoma , Perfilación de la Expresión Génica
6.
J Chem Ecol ; 50(9-10): 430-438, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38958679

RESUMEN

Male orchid bees are unique in the animal kingdom for making perfumes that function as sex pheromone. Males collect volatile chemicals from the environment in the neotropical forests, including floral and non-floral sources, creating complex but species-specific blends. Male orchid bees exhibit several adaptations to facilitate perfume collection and storage. When collecting volatile compounds, males apply lipid substances that they secrete from cephalic labial glands onto the fragrant substrate. These lipids help dissolve and retain the volatiles, similar to the process of 'enfleurage' in the traditional perfume industry. We investigated how the chemical composition of acquired perfume and labial gland secretions varied across the phylogeny of orchid bees, including 65 species in five genera from Central and South America. Perfumes showed rapid evolution as revealed by low overall phylogenetic signal, in agreement with the idea that perfume compounds diverge rapidly and substantially among closely related species due to their role in species recognition. A possible exception were perfumes in the genus Eulaema, clustering closely in chemospace, partly mediated by high proportions of carvone and trans-carvone oxide. Labial gland secretions, in contrast, showed a strong phylogenetic signal at the genus level, with secretions of Eufriesea and Exaerete dominated by fatty acids and Eulaema dominated by saturated acetates of chain lengths 12 to 16 C-atoms. Secretions of the majority of Euglossa were heavily dominated by one unsaturated long chain diacetate, (9Z)-Eicosen-1,20-diyldiacetate. However, we also identified few highly divergent species of Euglossa in four subclades (11 species) that appear to have secondarily replaced the diacetate with other compounds. In comparison with environment-derived perfumes, the evolution of labial gland secretion is much slower, likely constrained by the underlying biochemical pathways, but perhaps influenced by perfume-solvent chemical interactions.


Asunto(s)
Orchidaceae , Filogenia , Animales , Abejas/metabolismo , Abejas/química , Masculino , Orchidaceae/química , Orchidaceae/metabolismo , Lípidos/análisis , Lípidos/química , Perfumes/análisis , Perfumes/química , Perfumes/metabolismo , Atractivos Sexuales/química , Atractivos Sexuales/metabolismo , Atractivos Sexuales/análisis , Evolución Biológica , Compuestos Orgánicos Volátiles/metabolismo , Compuestos Orgánicos Volátiles/análisis , Compuestos Orgánicos Volátiles/química , Especificidad de la Especie
7.
J Chem Ecol ; 50(1-2): 1-10, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38110848

RESUMEN

Sex pheromones are species-specific chemical signals that facilitate the location, identification, and selection of mating partners. These pheromones can vary between individuals, and act as signals of mate quality. Here, we investigate the variation of male pheromones in the mesosomal glands of the large carpenter bee Xylocopa sonorina, within a Northern California population. We tested the hypothesis that morphological traits are correlated with the observed variation in chemical blend composition of these bees. We also conducted behavioral assays to test whether these male pheromones act as long-range attractants to conspecifics. We found that larger males with darker mesosomal glands have a higher pheromone amount in their glands. Our analysis also suggests that this pheromone blend functions as a long-range attractant to both males and females. We show that both male body size and sexual maturation are important factors influencing pheromone abundance, and that this pheromone blend acts as a long-range attractant. We hypothesize that this recorded variation in male pheromone could be important for female choice.


Asunto(s)
Preferencia en el Apareamiento Animal , Atractivos Sexuales , Humanos , Abejas , Masculino , Femenino , Animales , Feromonas , Conducta Sexual Animal , Reproducción
8.
Appl Microbiol Biotechnol ; 108(1): 258, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38466440

RESUMEN

Environmental concerns about residues and the traditional disposal methods are driving the search for more environmentally conscious processes, such as pyrolysis and gasification. Their main final product is synthesis gas (syngas) composed of CO, CO2, H2, and methane. Syngas can be converted into various products using CO-tolerant microorganisms. Among them, Rhodospirillum rubrum is highlighted for its biotechnological potential. However, the extent to which high doses of CO affect its physiology is still opaque. For this reason, we have studied R. rubrum behavior under high levels of this gas (up to 2.5 bar), revealing a profound dependence on the presence or absence of light. In darkness, the key variable affected was the lag phase, where the highest levels of CO retarded growth to more than 20 days. Under light, R. rubrum ability to convert CO into CO2 and H2 depended on the presence of an additional carbon source, such as acetate. In those conditions where CO was completely exhausted, CO2 fixation was unblocked, leading to a diauxic growth. To enhance R. rubrum tolerance to CO in darkness, a UV-accelerated adaptive laboratory evolution (UVa-ALE) trial was conducted to isolate clones with shorter lag phases, resulting in the isolation of clones 1.4-2B and 1.7-2A. The adaptation of 1.4-2B was mainly based on mutated enzymes with a metabolic function, while 1.7-3A was mostly affected at regulatory genes, including the anti-repressor PpaA/AerR. Despite these mutations having slight effects on biomass and pigment levels, they successfully provoked a significant reduction in the lag phase (-50%). KEYPOINTS: • CO affects principally R. rubrum lag phase (darkness) and growth rate (light) • CO is converted to CO2/H2 during acetate uptake and inhibits CO2 fixation (light) • UVa-ALE clones showed a 50% reduction in the lag phase (darkness).


Asunto(s)
Monóxido de Carbono , Rhodospirillum rubrum , Monóxido de Carbono/metabolismo , Rhodospirillum rubrum/genética , Rhodospirillum rubrum/metabolismo , Dióxido de Carbono/metabolismo , Acetatos/metabolismo
9.
J Stroke Cerebrovasc Dis ; 33(4): 107553, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38340555

RESUMEN

INTRODUCTION: Delayed Cerebral Ischemia (DCI) is a significant complication following aneurysmal subarachnoid hemorrhage (aSAH) that can lead to poor outcomes. Machine learning techniques have shown promise in predicting DCI and improving risk stratification. METHODS: In this study, we aimed to develop machine learning models to predict the occurrence of DCI in patients with aSAH. Patient data, including various clinical variables and co-factors, were collected. Six different machine learning models, including logistic regression, multilayer perceptron, decision tree, random forest, gradient boosting machine, and extreme gradient boosting (XGB), were trained and evaluated using performance metrics such as accuracy, area under the curve (AUC), precision, recall, and F1 score. RESULTS: After data augmentation, the random forest model demonstrated the best performance, with an AUC of 0.85. The multilayer perceptron neural network model achieved an accuracy of 0.93 and an F1 score of 0.85, making it the best performing model. The presence of positive clinical vasospasm was identified as the most important feature for predicting DCI. CONCLUSIONS: Our study highlights the potential of machine learning models in predicting the occurrence of DCI in patients with aSAH. The multilayer perceptron model showed excellent performance, indicating its utility in risk stratification and clinical decision-making. However, further validation and refinement of the models are necessary to ensure their generalizability and applicability in real-world settings. Machine learning techniques have the potential to enhance patient care and improve outcomes in aSAH, but their implementation should be accompanied by careful evaluation and validation.


Asunto(s)
Isquemia Encefálica , Hemorragia Subaracnoidea , Humanos , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/diagnóstico por imagen , Isquemia Encefálica/etiología , Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Aprendizaje Automático , Factores de Tiempo
10.
J Helminthol ; 98: e18, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38347824

RESUMEN

A new species of the free-living nematode genus Trachactinolaimus, collected in natural habitats of northern Iran, is described, including morphological and molecular (28S-rDNA) data. Trachactinolaimus persicus sp. n. is characterized by its 1.95-2.44 mm long body, lip region weakly offset by depression and 18-20 µm wide, odontostyle 25-27 µm long, neck 540-636 µm long, pharyngeal expansion occupying one-half of the total neck length, bipartite uterus 2.6-3.9 body diameters long, vulva (V = 49-53) pore-like, tail long and filiform in both sexes (174-223 µm, c = 10.0-13.4, c' = 5.9-7.0 in females, 165-196 µm, c = 10.7-13.8, c' = 4.6-5.8 in males), spicules 68-75 µm long, and 12-14 almost contiguous ventromedian supplements with hiatus. Molecular data supports the monophyly of the genus and the hypothesis that Dorylaimidae are the sister group of actinolaims. The taxonomy of Trachactinolaimus is updated, including diagnosis, list of species, key to their identification, and a compendium of their main morphometrics. Dominiactinolaimus is regarded as its junior synonym.


Asunto(s)
Helmintos , Nematodos , Masculino , Femenino , Animales , Irán , Evolución Biológica , Filogenia
11.
J Helminthol ; 98: e32, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38618914

RESUMEN

Two new species of the genus Sectonema found in northern Iran are characterized, including morphological descriptions and molecular (18S-, 28S-rDNA) analyses. Sectonema tehranense sp. nov. is distinguished by its 7.22 - 8.53 mm long body, lip region offset by constriction and 24 - 31 µm wide with perioral lobes and abundant setae- or cilia-like projections covering the oral field, mural tooth 15.5 - 17 µm long at its ventral side, neck 1091 - 1478 µm long, pharyngeal expansion occupying 61 - 71% of the total neck length, female genital system diovarian, uterus simple and 3.9 - 4.2 times the corresponding body diameter long, transverse vulva (V = 49 - 59), tail short and rounded (44 - 65 µm, c = 99 - 162, c' = 0.6 - 0.8), spicules 111 - 127 µm long, and 7 - 10 spaced ventromedian supplements with hiatus. Sectonema noshahrense sp. nov. displays a 4.07 - 4.73 mm long body, lip region offset by constriction and 23 - 25 µm wide with perioral lobes and abundant setae- or cilia-like projections covering the oral field, odontostyle 14 - 14.5 µm long, neck 722 - 822 µm long, pharyngeal expansion occupying 66 - 68% of the total neck length, female genital system diovarian, uterus simple and 2.4 - 2.7 times the corresponding body diameter long, transverse vulva (V = 54 - 55), tail convex conoid (39 - 47 µm, c = 91 - 111, c' = 0.8 - 0.9), spicules 82 µm long, and seven spaced ventromedian supplements with hiatus. Molecular analyses confirm a maximally supported (Epacrolaimus + Metaporcelaimus + Sectonema) clade and a tentative biogeographical pattern, with sequences of Indolamayan taxa forming a clade separated from those of Palearctic ones. Parallel or convergent evolution processes might be involved in the phylogeny of the species currently classified under Sectonema. This genus is certainly more heterogeneous than previously assumed.


Asunto(s)
Helmintos , Nematodos , Femenino , Animales , Irán , Citoesqueleto , ADN Ribosómico/genética , Nematodos/genética
12.
Mol Biol Evol ; 39(2)2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34963012

RESUMEN

The diversity of herbivorous insects is attributed to their propensity to specialize on toxic plants. In an evolutionary twist, toxins betray the identity of their bearers when herbivores coopt them as cues for host-plant finding, but the evolutionary mechanisms underlying this phenomenon are poorly understood. We focused on Scaptomyza flava, an herbivorous drosophilid specialized on isothiocyanate (ITC)-producing (Brassicales) plants, and identified Or67b paralogs that were triplicated as mustard-specific herbivory evolved. Using in vivo heterologous systems for the expression of olfactory receptors, we found that S. flava Or67bs, but not the homologs from microbe-feeding relatives, responded selectively to ITCs, each paralog detecting different ITC subsets. Consistent with this, S. flava was attracted to ITCs, as was Drosophila melanogaster expressing S. flava Or67b3 in the homologous Or67b olfactory circuit. ITCs were likely coopted as olfactory attractants through gene duplication and functional specialization (neofunctionalization and subfunctionalization) in S. flava, a recently derived herbivore.


Asunto(s)
Drosophilidae , Receptores Odorantes , Animales , Drosophila melanogaster , Drosophilidae/genética , Herbivoria/genética , Planta de la Mostaza , Aceites de Plantas , Receptores Odorantes/genética
13.
J Evol Biol ; 36(4): 675-686, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36820763

RESUMEN

Traits that mediate reproductive isolation between species, such as those involved in mate choice and/or recognition, are predicted to experience stabilizing selection towards the species mean. Male orchid bees collect chemical compounds from many sources, such as plants and fungi, which they use as a perfume signal (pheromone) during courtship display, and are suggested to contribute to reproductive isolation between species. Environmentally acquired signals are more prone to variation as source availability can vary through space and time. If orchid bee perfumes are important for reproductive isolation between species, we expect them to exhibit stable species-specific differences in time and space. Here, we describe phenotypic patterns of inter- and intraspecific variation in the male perfumes of three sympatric species of Euglossa orchid bees across an entire year, investigating both their seasonality and species specificity. Our analysis revealed considerable within-species variation in perfumes. However, species specificity was maintained consistently throughout the year, supporting the idea that these perfumes could play an important role in reproductive isolation and are experiencing stabilizing selection towards a species mean. Our analysis also identified strong correlations in the abundance of some compounds, possibly due to shared collection sources between species. Our study suggests that orchid bee perfumes are robust in the face of environmental changes in resource availability and thus can maintain reproductive isolation between species.


El aislamiento reproductivo entre especies es usualmente controlado por rasgos que juegan un papel importante en la selección y/o reconocimiento de pareja. Estos rasgos usualmente están bajo la presión de selección estabilizadora, lo que hace que se mantengan cerca al promedio de la especie. Los machos de las abejas de las orquídeas recolectan compuestos químicos de plantas y hongos y los usan como señales de feromonas durante el cortejo. Se piensa que las feromonas de las abejas de las orquídeas contribuyen al aislamiento reproductivo entre especies. Al ser obtenidas del ambiente, estas señales químicas (perfumes) son más propensas a la variación, ya que la disponibilidad de la fuente puede variar en el espacio y el tiempo. Si los perfumes contribuyen al aislamiento reproductivo, se esperaría que las diferencias entre especies sean estables tanto en el tiempo como en el espacio. Aquí, investigamos la estacionalidad y la especificidad a nivel de especie de los perfumes durante todo un año en tres especies simpátricas de abejas del género Euglossa. Nuestro análisis reveló variación considerable en los perfumes de cada especie. Sin embargo, la especificidad de cada especie se mantuvo durante todo el año, lo cual sugiere que los perfumes juegan un papel importante en el aislamiento reproductivo y que experimentan selección estabilizadora hacia la media de la especie. Nuestro análisis también identificó fuertes correlaciones en la abundancia de algunos compuestos, posiblemente debido a que diferentes especies comparten las mismas fuentes de recolección. Nuestro estudio sugiere que los perfumes de las abejas de las orquídeas son robustos frente a los cambios ambientales y la variación en la disponibilidad de recursos y por lo tanto pueden contribuir al aislamiento reproductivo.


Asunto(s)
Feromonas , Reproducción , Abejas , Animales , Especificidad de la Especie , Estaciones del Año
14.
Cerebrovasc Dis ; 52(5): 519-525, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36566750

RESUMEN

INTRODUCTION: Moyamoya has been extensively described in East Asian populations, and despite its accepted clinical presentation and course, it is fundamental to describe major cerebrovascular complications in other ethnically diverse samples. Hence, we sought to determine if distinct ethnic groups are at higher risk of developing stroke using the National Inpatient Sample (NIS) database. METHODS: We included all moyamoya patients admitted from January 2013 until December 2018 in the NIS database. Multivariate regression analysis was used to determine the risk of developing stroke and poor outcomes in different races compared to white patients. RESULTS: Out of the 6093 admissions with diagnosis of moyamoya disease that were captured, 2,520 were white (41.6%), 2,078 were African American (AA) (34.1%), 721 were Hispanic (11.8%), and 496 were Asian (8.14%). For arterial ischemic stroke (AIS), we found that AA race had a significantly reduced risk of AIS compared to white patients (odds ratio = 0.8, 95% confidence interval: 0.7-0.9, p = 0.031). While being Hispanic or Asian significantly increased 1.5 and 2-fold the risk of hemorrhagic stroke. CONCLUSION: This study highlights the unique features and phenotypes of moyamoya cases among different ethnicities. While possibly AA are protected from developing AIS due to underlying causes of moyamoya such as sickle cell disease, Asians seems to be more susceptible to hemorrhagic stroke.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular Isquémico , Enfermedad de Moyamoya , Accidente Cerebrovascular , Humanos , Enfermedad de Moyamoya/complicaciones , Enfermedad de Moyamoya/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Factores de Riesgo , Accidente Cerebrovascular Isquémico/complicaciones , Fenotipo
15.
Microb Cell Fact ; 22(1): 47, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36899367

RESUMEN

BACKGROUND: Microbially produced bioplastics are specially promising materials since they can be naturally synthesized and degraded, making its end-of-life management more amenable to the environment. A prominent example of these new materials are polyhydroxyalkanoates. These polyesters serve manly as carbon and energy storage and increase the resistance to stress. Their synthesis can also work as an electron sink for the regeneration of oxidized cofactors. In terms of biotechnological applications, the co-polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate), or PHBV, has interesting biotechnological properties due to its lower stiffness and fragility compared to the homopolymer poly(3-hydroxybutyrate) (P3HB). In this work, we explored the potentiality of Rhodospirillum rubrum as a producer of this co-polymer, exploiting its metabolic versatility when grown in different aeration conditions and photoheterotrophically. RESULTS: When shaken flasks experiments were carried out with limited aeration using fructose as carbon source, PHBV production was triggered reaching 29 ± 2% CDW of polymer accumulation with a 75 ± 1%mol of 3-hydroxyvalerate (3HV) (condition C2). Propionate and acetate were secreted in this condition. The synthesis of PHBV was exclusively carried out by the PHA synthase PhaC2. Interestingly, transcription of cbbM coding RuBisCO, the key enzyme of the Calvin-Benson-Bassham cycle, was similar in aerobic and microaerobic/anaerobic cultures. The maximal PHBV yield (81% CDW with 86%mol 3HV) was achieved when cells were transferred from aerobic to anaerobic conditions and controlling the CO2 concentration by adding bicarbonate to the culture. In these conditions, the cells behaved like resting cells, since polymer accumulation prevailed over residual biomass formation. In the absence of bicarbonate, cells could not adapt to an anaerobic environment in the studied lapse. CONCLUSIONS: We found that two-phase growth (aerobic-anaerobic) significantly improved the previous report of PHBV production in purple nonsulfur bacteria, maximizing the polymer accumulation at the expense of other components of the biomass. The presence of CO2 is key in this process demonstrating the involvement of the Calvin-Benson-Bassham in the adaptation to changes in oxygen availability. These results stand R. rubrum as a promising producer of high-3HV-content PHBV co-polymer from fructose, a PHBV unrelated carbon source.


Asunto(s)
Dióxido de Carbono , Rhodospirillum rubrum , Rhodospirillum rubrum/metabolismo , Anaerobiosis , Bicarbonatos , Poliésteres/metabolismo , Hidroxibutiratos
16.
Clin Exp Rheumatol ; 41(3): 704-710, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35930489

RESUMEN

OBJECTIVES: Patient centred care is an increasingly important paradigm. Applying a treat-to-target strategy to the impact of the disease in patients' lives seems a very promising tool to serve this purpose. We aimed to evaluate if maximum acceptable impact scores (target-values) defined at the population level provide an appropriate representation for most individual patients. To determine if the individually established target values of impact are consistent enough to be used in a treat-to-target strategy. METHODS: Consecutive patients with rheumatoid arthritis were asked to indicate, in two consecutive visits, the maximum severity of impact they considered acceptable to live with for the rest of their lives, in the seven domains of Rheumatoid Arthritis Impact of Disease score. The individual adequacy of population-based reference values was assessed by measures of dispersion. Stability of individual target-values were evaluated through intraclass correlation coefficient. Socio-demographic, clinical and psychological features were tested as co-factors of stability. RESULTS: 299 patients were included. The dispersion of targets was wide (CV>0.68), thus limiting the use of any population-based single values as targets for the individual patients. Although the mean target values were very similar in both visits for all domains, reliability was poor in all cases (ICCs: 0.37-0.47). Only 25-30% of the patients selected the same target value in the 2 visits. No explanatory factors for (non-)stability were identified. CONCLUSIONS: Quantified impact targets defined at population level are not appropriate for individual patient care. Research on alternative tools to support patient-centred, target-oriented management strategies is warranted.


Asunto(s)
Artritis Reumatoide , Humanos , Reproducibilidad de los Resultados , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/terapia , Artritis Reumatoide/psicología
17.
Platelets ; 34(1): 2216802, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37246516

RESUMEN

This prospective study was aimed to test changes in hemostasis in patients with GBM, occurring at baseline (before surgery, time 0, T0) and 2 (T2), 24 (T24), and 48-hour (T48) after surgery. We enrolled consecutive patients subjected to GBM resection (GBR group; N = 60), laparoscopic colon cancer resection (comparative CCR group; N = 40), and healthy blood donors (HBD group; N = 40). We performed 1. conventional coagulation tests 2. ROTEM (rotational thromboelastometry) parameters and 3. platelet function tests, including PFA-200 closure time when stimulated by collagen/epinephrine (COL-EPI) and ROTEM platelet, using three different activators (arachnoid acid in ARATEM, adenosine diphosphate in ADPTEM, and thrombin receptor-activating peptide-6 in TRAPTEM). Variables associated with unfavorable 1-year clinical outcome were investigated, too. We observed in GBR patients that platelet aggregometry, as assessed by ROTEM platelet parameters, was significantly impaired along with a shortened closure time. These changes were evident from T0 to T48. A decreased area under the aggregation curve in TRAPTEM was associated with improved survival (adjusted odd ratio (95% CI), 1.03 (1.01-1.06)). This study suggests that patients with GBM presented a decreased platelet aggregation from before surgery and thorough the postoperative period. Decreased platelet aggregation improved clinical outcome.


What is the context? Glioblastoma has an impact on the platelet number and the functional state of platelets. Platelets can be activated by tumor cells, and platelets count and function may impact patient survival. It has been showed an association between thrombocytosis and a decreased overall survival, with a small reduction in glioma risk associated with the long-term use of low-dose aspirin.Platelet function before and during the perioperative period in patients with glioblastoma has not been systematically investigated. Limited data suggest that platelet function may be impaired before and throughout the perioperative period, and that impaired platelet function affects clinical outcome.What is new? In this prospective study, we systematically investigated how glioblastoma provokes systemic alterations of hemostasis. We enrolled 60 consecutive patients (sample size calculated) subjected to resection of glioblastoma multiforme, and other 40 consecutive patients undergoing laparoscopic resection of colon cancer, as a comparative group, in order to differentiate hemostasis and coagulation profiles of two tumors (glioblastoma and colon adenocarcinoma) with high prothrombotic power. Forty healthy volunteers were also included to establish local reference values.We performed 1. conventional coagulation tests 2. ROTEM (rotational thromboelastometry) parameters and 3. platelet function tests, including PFA-200 closure time when stimulated by collagen/epinephrine (COL-EPI) and ROTEM platelet, using three different activators (arachnoid acid in ARATEM, adenosine diphosphate in ADPTEM, and thrombin receptor-activating peptide-6 in TRAPTEM). Variables associated with unfavorable 1-year clinical outcome were investigated, too. All these analyses were carried out at baseline (T0, time 0, before surgery) and 2 (T2), 24(T24) and 48-hour (T48) after surgery.We observed in GBR patients that platelet aggregometry, as assessed by ROTEM platelet parameters, was significantly impaired along with a shortened closure time. These changes were evident from T0 to T48. A decreased area under the aggregation curve in TRAPTEM was associated with improved survival (adjusted odd ratio (95% CI), 1.03 (1.01­1.06)).What is the impact? This study provides further evidence that patients with GBM presented a decreased platelet aggregation from before surgery and thorough the postoperative period. Decreased platelet aggregation improved clinical outcome.The cut-offs obtained can potentially to provide risk stratification for clinical outcome and to be hypothesis generating research to be confirmed by RCTs.


Asunto(s)
Glioblastoma , Agregación Plaquetaria , Humanos , Estudios Prospectivos , Glioblastoma/cirugía , Hemostasis , Pruebas de Coagulación Sanguínea , Plaquetas , Tromboelastografía
18.
PLoS Genet ; 16(10): e1009038, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33075065

RESUMEN

Recent biological invasions offer 'natural' laboratories to understand the genetics and ecology of adaptation, hybridization, and range limits. One of the most impressive and well-documented biological invasions of the 20th century began in 1957 when Apis mellifera scutellata honey bees swarmed out of managed experimental colonies in Brazil. This newly-imported subspecies, native to southern and eastern Africa, both hybridized with and out-competed previously-introduced European honey bee subspecies. Populations of scutellata-European hybrid honey bees rapidly expanded and spread across much of the Americas in less than 50 years. We use broad geographic sampling and whole genome sequencing of over 300 bees to map the distribution of scutellata ancestry where the northern and southern invasions have presently stalled, forming replicated hybrid zones with European bee populations in California and Argentina. California is much farther from Brazil, yet these hybrid zones occur at very similar latitudes, consistent with the invasion having reached a climate barrier. At these range limits, we observe genome-wide clines for scutellata ancestry, and parallel clines for wing length that span hundreds of kilometers, supporting a smooth transition from climates favoring scutellata-European hybrid bees to climates where they cannot survive winter. We find no large effect loci maintaining exceptionally steep ancestry transitions. Instead, we find most individual loci have concordant ancestry clines across South America, with a build-up of somewhat steeper clines in regions of the genome with low recombination rates, consistent with many loci of small effect contributing to climate-associated fitness trade-offs. Additionally, we find no substantial reductions in genetic diversity associated with rapid expansions nor complete dropout of scutellata ancestry at any individual loci on either continent, which suggests that the competitive fitness advantage of scutellata ancestry at lower latitudes has a polygenic basis and that scutellata-European hybrid bees maintained large population sizes during their invasion. To test for parallel selection across continents, we develop a null model that accounts for drift in ancestry frequencies during the rapid expansion. We identify several peaks within a larger genomic region where selection has pushed scutellata ancestry to high frequency hundreds of kilometers past the present cline centers in both North and South America and that may underlie high-fitness traits driving the invasion.


Asunto(s)
Abejas/genética , Genoma de los Insectos/genética , Hibridación Genética/genética , Selección Genética/genética , África Oriental , Américas , Animales , Argentina , Brasil , California , Miel , Hibridación de Ácido Nucleico , Polimorfismo de Nucleótido Simple/genética , Secuenciación Completa del Genoma
19.
Proc Natl Acad Sci U S A ; 117(46): 28887-28893, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33139548

RESUMEN

Migratory animals exhibit traits that allow them to exploit seasonally variable habitats. In environments where migration is no longer beneficial, such as oceanic islands, migration-association traits may be selected against or be under relaxed selection. Monarch butterflies are best known for their continent-scale migration in North America but have repeatedly become established as nonmigrants in the tropical Americas and on Atlantic and Pacific Islands. These replicated nonmigratory populations provide natural laboratories for understanding the rate of evolution of migration-associated traits. We measured >6,000 museum specimens of monarch butterflies collected from 1856 to the present as well as contemporary wild-caught monarchs from around the world. We determined 1) how wing morphology varies across the monarch's global range, 2) whether initial long-distance founders were particularly suited for migration, and 3) whether recently established nonmigrants show evidence for contemporary phenotypic evolution. We further reared >1,000 monarchs from six populations around the world under controlled conditions and measured migration-associated traits. Historical specimens show that 1) initial founders are well suited for long-distance movement and 2) loss of seasonal migration is associated with reductions in forewing size and elongation. Monarch butterflies raised in a common garden from four derived nonmigratory populations exhibit genetically based reductions in forewing size, consistent with a previous study. Our findings provide a compelling example of how migration-associated traits may be favored during the early stages of range expansion, and also the rate of reductions in those same traits upon loss of migration.


Asunto(s)
Mariposas Diurnas/anatomía & histología , Alas de Animales/anatomía & histología , Migración Animal/fisiología , Animales , Evolución Biológica , Mariposas Diurnas/fisiología , América del Norte , Oceanía , Fenotipo , Alas de Animales/fisiología
20.
Proc Natl Acad Sci U S A ; 117(31): 18574-18581, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32661155

RESUMEN

Many vertebrates have distinctive blue-green bones and other tissues due to unusually high biliverdin concentrations-a phenomenon called chlorosis. Despite its prevalence, the biochemical basis, biology, and evolution of chlorosis are poorly understood. In this study, we show that the occurrence of high biliverdin in anurans (frogs and toads) has evolved multiple times during their evolutionary history, and relies on the same mechanism-the presence of a class of serpin family proteins that bind biliverdin. Using a diverse combination of techniques, we purified these serpins from several species of nonmodel treefrogs and developed a pipeline that allowed us to assemble their complete amino acid and nucleotide sequences. The described proteins, hereafter named biliverdin-binding serpins (BBS), have absorption spectra that mimic those of phytochromes and bacteriophytochromes. Our models showed that physiological concentration of BBSs fine-tune the color of the animals, providing the physiological basis for crypsis in green foliage even under near-infrared light. Additionally, we found that these BBSs are most similar to human glycoprotein alpha-1-antitrypsin, but with a remarkable functional diversification. Our results present molecular and functional evidence of recurrent evolution of chlorosis, describe a biliverdin-binding protein in vertebrates, and introduce a function for a member of the serpin superfamily, the largest and most ubiquitous group of protease inhibitors.


Asunto(s)
Anuros/fisiología , Biliverdina/metabolismo , Serpinas/metabolismo , Pigmentación de la Piel/fisiología , Animales , Anuros/clasificación , Anuros/genética , Biliverdina/química , Mimetismo Biológico/fisiología , Serpinas/química , Serpinas/genética , Pigmentación de la Piel/genética
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