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1.
Cell ; 178(5): 1057-1071.e11, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31442400

RESUMEN

The Zika epidemic in the Americas has challenged surveillance and control. As the epidemic appears to be waning, it is unclear whether transmission is still ongoing, which is exacerbated by discrepancies in reporting. To uncover locations with lingering outbreaks, we investigated travel-associated Zika cases to identify transmission not captured by reporting. We uncovered an unreported outbreak in Cuba during 2017, a year after peak transmission in neighboring islands. By sequencing Zika virus, we show that the establishment of the virus was delayed by a year and that the ensuing outbreak was sparked by long-lived lineages of Zika virus from other Caribbean islands. Our data suggest that, although mosquito control in Cuba may initially have been effective at mitigating Zika virus transmission, such measures need to be maintained to be effective. Our study highlights how Zika virus may still be "silently" spreading and provides a framework for understanding outbreak dynamics. VIDEO ABSTRACT.


Asunto(s)
Epidemias , Genómica/métodos , Infección por el Virus Zika/epidemiología , Aedes/virología , Animales , Cuba/epidemiología , Humanos , Incidencia , Control de Mosquitos , Filogenia , ARN Viral/química , ARN Viral/metabolismo , Análisis de Secuencia de ARN , Viaje , Indias Occidentales/epidemiología , Virus Zika/clasificación , Virus Zika/genética , Virus Zika/aislamiento & purificación , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/virología
2.
Proc Natl Acad Sci U S A ; 120(7): e2201944119, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36745805

RESUMEN

Biodiversity loss poses a major threat to ecosystem function, which has already been severely impacted by global late-Quaternary defaunation. The loss of mammalian megafauna from many insular systems has rendered reptiles into key modulators of many ecosystem services, such as seed dispersal and pollination. How late-Quaternary extinction events impacted reptile functional diversity remains unclear but can provide critical guidance on traits that render reptiles vulnerable to extinction, as well as anthropogenic, environmental, and evolutionary histories that may promote stability and resilience. This study reconstructs the trajectory of functional diversity change in the Caribbean reptile fauna, a speciose biota distributed over a diverse set of islands with heterogeneous histories of human habitation and exploitation. Human-induced Quaternary extinctions have completely removed key functional entities (FEs)-groupings of species with similar traits that are expected to provide similar ecosystem services-from the region, but functional redundancy on large islands served as a buffer to major functional diversity loss. Small islands, on the other hand, lose up to 67% of their native FEs with only a few exceptions, underscoring the importance of a place's anthropogenic history in shaping present-day biodiversity. While functional redundancy has shielded ecosystems from significant functional diversity loss in the past, it is being eroded and not replenished by species introductions, leaving many native FEs and the communities that they support vulnerable to extinction and functional collapse. This research provides critical data on long-term functional diversity loss for a taxonomic group whose contributions to ecosystem function are understudied and undervalued.


Asunto(s)
Biodiversidad , Ecosistema , Animales , Humanos , Biota , Reptiles , Indias Occidentales , Mamíferos
3.
Proc Natl Acad Sci U S A ; 120(41): e2301128120, 2023 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-37748079

RESUMEN

Humans did not arrive on most of the world's islands until relatively recently, making islands favorable places for disentangling the timing and magnitude of natural and anthropogenic impacts on species diversity and distributions. Here, we focus on Amazona parrots in the Caribbean, which have close relationships with humans (e.g., as pets as well as sources of meat and colorful feathers). Caribbean parrots also have substantial fossil and archaeological records that span the Holocene. We leverage this exemplary record to showcase how combining ancient and modern DNA, along with radiometric dating, can shed light on diversification and extinction dynamics and answer long-standing questions about the magnitude of human impacts in the region. Our results reveal a striking loss of parrot diversity, much of which took place during human occupation of the islands. The most widespread species, the Cuban Parrot, exhibits interisland divergences throughout the Pleistocene. Within this radiation, we identified an extinct, genetically distinct lineage that survived on the Turks and Caicos until Indigenous human settlement of the islands. We also found that the narrowly distributed Hispaniolan Parrot had a natural range that once included The Bahamas; it thus became "endemic" to Hispaniola during the late Holocene. The Hispaniolan Parrot also likely was introduced by Indigenous people to Grand Turk and Montserrat, two islands where it is now also extirpated. Our research demonstrates that genetic information spanning paleontological, archaeological, and modern contexts is essential to understand the role of humans in altering the diversity and distribution of biota.


Asunto(s)
Amazona , Animales , Humanos , Indias Occidentales , Región del Caribe , Bahamas , Efectos Antropogénicos
4.
Nature ; 570(7759): 58-64, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31168105

RESUMEN

Biological invasions are both a pressing environmental challenge and an opportunity to investigate fundamental ecological processes, such as the role of top predators in regulating biodiversity and food-web structure. In whole-ecosystem manipulations of small Caribbean islands on which brown anole lizards (Anolis sagrei) were the native top predator, we experimentally staged invasions by competitors (green anoles, Anolis smaragdinus) and/or new top predators (curly-tailed lizards, Leiocephalus carinatus). We show that curly-tailed lizards destabilized the coexistence of competing prey species, contrary to the classic idea of keystone predation. Fear-driven avoidance of predators collapsed the spatial and dietary niche structure that otherwise stabilized coexistence, which intensified interspecific competition within predator-free refuges and contributed to the extinction of green-anole populations on two islands. Moreover, whereas adding either green anoles or curly-tailed lizards lengthened food chains on the islands, adding both species reversed this effect-in part because the apex predators were trophic omnivores. Our results underscore the importance of top-down control in ecological communities, but show that its outcomes depend on prey behaviour, spatial structure, and omnivory. Diversity-enhancing effects of top predators cannot be assumed, and non-consumptive effects of predation risk may be a widespread constraint on species coexistence.


Asunto(s)
Biodiversidad , Cadena Alimentaria , Lagartos/fisiología , Conducta Predatoria , Animales , Evolución Biológica , Biota , Conducta Competitiva , Conducta Alimentaria , Femenino , Lagartos/clasificación , Masculino , Especificidad de la Especie , Indias Occidentales
5.
Mol Ecol ; 33(8): e17321, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38529721

RESUMEN

Fundamental to holobiont biology is recognising how variation in microbial composition and function relates to host phenotypic variation. Sponges often exhibit considerable phenotypic plasticity and also harbour dense microbial communities that function to protect and nourish hosts. One of the most prominent sponge genera on Caribbean coral reefs is Agelas. Using a comprehensive set of morphological (growth form, spicule), chemical and molecular data on 13 recognised species of Agelas in the Caribbean basin, we were able to define only five species (=clades) and found that many morphospecies designations were incongruent with phylogenomic and population genetic analyses. Microbial communities were also strongly differentiated between phylogenetic species, showing little evidence of cryptic divergence and relatively low correlation with morphospecies assignment. Metagenomic analyses also showed strong correspondence to phylogenetic species, and to a lesser extent, geographical and morphological characters. Surprisingly, the variation in secondary metabolites produced by sponge holobionts was explained by geography and morphospecies assignment, in addition to phylogenetic species, and covaried significantly with a subset of microbial symbionts. Spicule characteristics were highly plastic, under greater impact from geographical location than phylogeny. Our results suggest that while phenotypic plasticity is rampant in Agelas, morphological differences within phylogenetic species affect functionally important ecological traits, including the composition of the symbiotic microbial communities and metabolomic profiles.


Asunto(s)
Agelas , Poríferos , Animales , Filogenia , Región del Caribe , Indias Occidentales , Arrecifes de Coral , Poríferos/genética
6.
Nature ; 560(7716): 88-91, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30046104

RESUMEN

Hurricanes are catastrophically destructive. Beyond their toll on human life and livelihoods, hurricanes have tremendous and often long-lasting effects on ecological systems1,2. Despite many examples of mass mortality events following hurricanes3-5, hurricane-induced natural selection has not previously been demonstrated. Immediately after we finished a survey of Anolis scriptus-a common, small-bodied lizard found throughout the Turks and Caicos archipelago-our study populations were battered by Hurricanes Irma and Maria. Shortly thereafter, we revisited the populations to determine whether morphological traits related to clinging capacity had shifted in the intervening six weeks and found that populations of surviving lizards differed in body size, relative limb length and toepad size from those present before the storm. Our serendipitous study, which to our knowledge is the first to use an immediately before and after comparison6 to investigate selection caused by hurricanes, demonstrates that hurricanes can induce phenotypic change in a population and strongly implicates natural selection as the cause. In the decades ahead, as extreme climate events are predicted to become more intense and prevalent7,8, our understanding of evolutionary dynamics needs to incorporate the effects of these potentially severe selective episodes9-11.


Asunto(s)
Tormentas Ciclónicas , Desastres , Lagartos/anatomía & histología , Selección Genética , Animales , Tamaño Corporal , Extremidades/anatomía & histología , Femenino , Fémur/anatomía & histología , Húmero/anatomía & histología , Islas , Masculino , Indias Occidentales
7.
Environ Res ; 246: 117955, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38159660

RESUMEN

BACKGROUND: The cardiotoxicity of prenatal exposure to mercury has been suggested in populations having regular contaminated seafood intake, though replications in the literature are inconsistent. METHODS: The Timoun Mother-Child Cohort Study was set up in Guadeloupe, an island in the Caribbean Sea where seafood consumption is regular. At seven years of age, 592 children underwent a medical examination, including cardiac function assessment. Blood pressure (BP) was taken using an automated blood pressure monitor, heart rate variability (HRV, 9 parameters) and electrocardiogram (ECG) characteristics (QT, T-wave parameters) were measured using Holter cardiac monitoring during the examination. Total mercury concentrations were measured in cord blood at birth (median = 6.6 µg/L, N = 399) and in the children's blood at age 7 (median = 1.7 µg/L, N = 310). Adjusted linear and non-linear modelling was used to study the association of each cardiac parameter with prenatal and childhood exposures. Sensitivity analyses included co-exposures to lead and cadmium, adjustment for maternal seafood consumption, selenium and polyunsaturated fatty acids (n3-PUFAs), and for sporting activity. RESULTS: Higher prenatal mercury was associated with higher systolic BP at 7 years of age (ßlog2 = 1.02; 95% Confidence Interval (CI) = 0.10, 1.19). In boys, intermediate prenatal exposure was associated with reduced overall HRV and parasympathetic activity, and longer QT was observed with increasing prenatal mercury (ßlog2 = 4.02; CI = 0.48, 7.56). In girls, HRV tended to increase linearly with prenatal exposure, and no association was observed with QT-wave related parameters. Mercury exposure at 7 years was associated with decreased BP in girls (ßlog2 = -1.13; CI = -2.22, -0.004 for diastolic BP). In boys, the low/high-frequency (LF/HF) ratio increased for intermediate levels of exposure. CONCLUSION: Our study suggests sex-specific and non-monotonic modifications in some cardiac health parameters following prenatal exposure to mercury in pre-pubertal children from an insular fish-consuming population.


Asunto(s)
Mercurio , Efectos Tardíos de la Exposición Prenatal , Masculino , Embarazo , Recién Nacido , Femenino , Animales , Humanos , Niño , Mercurio/análisis , Estudios de Cohortes , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Guadalupe/epidemiología , Indias Occidentales
8.
Euro Surveill ; 29(13)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38551097

RESUMEN

In 2023, dengue virus serotype 2 (DENV2) affected most French overseas territories. In the French Caribbean Islands, viral circulation continues with > 30,000 suspected infections by March 2024. Genome sequence analysis reveals that the epidemic lineage in the French Caribbean islands has also become established in French Guiana but not Réunion. It has moreover seeded autochthonous circulation events in mainland France. To guide prevention of further inter-territorial spread and DENV introduction in non-endemic settings, continued molecular surveillance and mosquito control are essential.


Asunto(s)
Epidemias , Humanos , Guyana Francesa/epidemiología , Epidemiología Molecular , Indias Occidentales/epidemiología , Francia/epidemiología
9.
Mol Biol Evol ; 39(11)2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36251862

RESUMEN

Despite a century of genetic analysis, the evolutionary processes that have generated the patterns of exceptional genetic and phenotypic variation in the model organism Drosophila melanogaster remains poorly understood. In particular, how genetic variation is partitioned within its putative ancestral range in Southern Africa remains unresolved. Here, we study patterns of population genetic structure, admixture, and the spatial structuring of candidate incompatibility alleles across a global sample, including 223 new accessions, predominantly from remote regions in Southern Africa. We identify nine major ancestries, six that primarily occur in Africa and one that has not been previously described. We find evidence for both contemporary and historical admixture between ancestries, with admixture rates varying both within and between continents. For example, while previous work has highlighted an admixture zone between broadly defined African and European ancestries in the Caribbean and southeastern USA, we identify West African ancestry as the most likely African contributor. Moreover, loci showing the strongest signal of introgression between West Africa and the Caribbean/southeastern USA include several genes relating to neurological development and male courtship behavior, in line with previous work showing shared mating behaviors between these regions. Finally, while we hypothesized that potential incompatibility loci may contribute to population genetic structure across the range of D. melanogaster; these loci are, on average, not highly differentiated between ancestries. This work contributes to our understanding of the evolutionary history of a key model system, and provides insight into the partitioning of diversity across its range.


Asunto(s)
Evolución Biológica , Drosophila melanogaster , Animales , Drosophila melanogaster/genética , Alelos , África , Indias Occidentales , Genética de Población , Variación Genética
10.
J Autoimmun ; 139: 103086, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37356346

RESUMEN

OBJECTIVES: To describe the epidemiology, characteristics, response to initial treatment, and outcomes of Adult-Onset Still's disease (AOSD) in the Afro-Caribbean population of Martinique with free and easy access to specialised care. METHODS: We conducted a retrospective study from 2004 to 2022 in the island of Martinique, French West-Indies which total population was 354 800 in 2021. Patients were identified from multiple sources including standardised databases. To be included, patients had to be residents of the island and fulfilled Yamaguchi and/or Fautrel's criteria for AOSD, or have a compatible disease course, without a diagnosis of cancer, auto-immune disease or another auto-inflammatory disorder. Date of diagnosis, clinical and biological characteristics, treatments, and outcomes were collected. RESULTS: The prevalence was 7.6/100 000 inhabitants in 2021. The mean incidence was 0.4/100 000 during study period. Thirty-three patients (70.6% females) with a median follow-up of 35 months [7.5 to 119] were included. Twenty-six patients (78.8%) had a systemic pattern. Patients with a systemic monocyclic pattern had significantly more polyarticular involvement than patients with systemic polycyclic pattern (p = 0.016). Pulmonary involvement occurred in 51.5% of patients at diagnosis and systemic Pouchot score has been identified as an independent predictive factor for pulmonary involvement; OR of 3.29 [CI 95% 1.20; 9.01]. At first flare, all patients but one received oral glucocorticoids, 11 patients (32.4%) received intravenous glucocorticoids pulse and 12 patients (33%) received anti-IL1 therapy. Nineteen patients (57%) relapsed in a median time of 9 months [6 to 12] Three patients (9%) developed hemophagocytosis lymphohistiocytosis, fatal in 1 case. All deceased patients (n = 4, 11.76%) belonged to the systemic polycyclic pattern, with an event-free survival of 13.6 months [IQR 5.7; 29.5] CONCLUSION: AOSD in the Afro-Caribbean population of Martinique shares some similarities with other ethnic groups, but exhibit differences, such as a high proportion of lung involvement. Comparative studies are needed to confirm these results.


Asunto(s)
Enfermedad de Still del Adulto , Adulto , Femenino , Humanos , Masculino , Pueblos Caribeños/estadística & datos numéricos , Etnicidad , Glucocorticoides/uso terapéutico , Martinica/epidemiología , Estudios Retrospectivos , Enfermedad de Still del Adulto/diagnóstico , Enfermedad de Still del Adulto/tratamiento farmacológico , Enfermedad de Still del Adulto/epidemiología , Enfermedad de Still del Adulto/etnología , Indias Occidentales/epidemiología
11.
BMC Cancer ; 23(1): 1197, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057723

RESUMEN

BACKGROUND: A worldwide increased incidence of HM has been marked in recent decades. Therefore, to update epidemiological characteristics of HM in a French West Indies territory, we have performed analysis through Martinique's population-based cancer registry database. METHODS: We included cancer case data, from 2009-2018, coded in strict compliance with international standards set by International Agency for Research on Cancer. We calculated standardized incidence rates, cumulative rate (ages 0-74), and temporal trends for cases and deaths using the global population standard, by sex and five age group. Mortality rates were obtained from the French Epidemiology Center on Medical Causes of Death (CépiDc). RESULTS: One thousand forty seven new cases and 674 deaths from HM were recorded, of which 501 MM (47.8%), 377 LMNH (36%), 123 LAM (11.8%), and 46 LH (4.4%) were reported in both sexes. MM is one of the hematological malignancies with the highest incidence in Martinique among men. Temporal trends of incidence rates for all HM decreased overall in both sexes, except for MM in men. There is significant variability in mortality rates for both sexes. In addition, over the period, the temporal trends of mortality rates for all HMs has decreased overall. Gender-specific rates, between 2009 and 2018, showed that all lymphoid HM have a multimodal distribution curve that increased with age. CONCLUSIONS: Characteristics of HM in Martinique over the reporting periods differ from mainland France. Higher incidences have been observed, particularly for MM, and non-significant sub-mortality is observed compared to mainland France. Moreover, temporal distribution of mortality and incidence trends had decreased over the reporting periods except for MM. Our results showed similarities with African-Americans groups in United States and in particular an equivalence in the frequency distribution of diagnosed HM. However, SMR remains lower compared to US black ethnic groups. Our results contributed to expanding knowledge on the epidemiology of HM with Caribbean data.


Asunto(s)
Neoplasias Hematológicas , Neoplasias , Masculino , Femenino , Humanos , Neoplasias/epidemiología , Neoplasias Hematológicas/epidemiología , Indias Occidentales , Incidencia , Sistema de Registros
12.
Ann Bot ; 131(7): 1133-1147, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37208295

RESUMEN

BACKGROUND AND AIMS: The genus Buxus has high levels of endemism in the Caribbean flora, with ~50 taxa. In Cuba, 82 % grow on ultramafic substrates and 59 % are nickel (Ni) accumulators or Ni hyperaccumulators. Hence it is an ideal model group to study if this diversification could be related to adaptation to ultramafic substrates and to Ni hyperaccumulation. METHODS: We generated a well-resolved molecular phylogeny, including nearly all of the Neotropical and Caribbean Buxus taxa. To obtain robust divergence times we tested for the effects of different calibration scenarios, and we reconstructed ancestral areas and ancestral character states. Phylogenetic trees were examined for trait-independent shifts in diversification rates and we used multi-state models to test for state-dependent speciation and extinction rates. Storms could have contributed to Cuba acting as a species pump and to Buxus reaching other Caribbean islands and northern South America'. KEY RESULTS: We found a Caribbean Buxus clade with Mexican ancestors, encompassing three major subclades, which started to radiate during the middle Miocene (13.25 Mya). Other Caribbean islands and northern South America were reached from ~3 Mya onwards. CONCLUSIONS: An evolutionary scenario is evident in which Buxus plants able to grow on ultramafic substrates by exaptation became ultramafic substrate endemics and evolved stepwise from Ni tolerance through Ni accumulation to Ni hyperaccumulation, which has triggered species diversification of Buxus in Cuba. Storms could have contributed to Cuba acting as a species pump and to Buxus reaching other Caribbean islands and northern South America'.


Asunto(s)
Buxus , Níquel , Filogenia , Cuba , Islas , Región del Caribe , Indias Occidentales , Especiación Genética
13.
Proc Natl Acad Sci U S A ; 117(3): 1587-1595, 2020 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-31907312

RESUMEN

Many large-bodied marine fishes that form spawning aggregations, such as the Nassau grouper (Epinephelus striatus), have suffered regional overfishing due to exploitation during spawning. In response, marine resource managers in many locations have established marine protected areas or seasonal closures to recover these overfished stocks. The challenge in assessing management effectiveness lies largely in the development of accurate estimates to track stock size through time. For the past 15 y, the Cayman Islands government has taken a series of management actions aimed at recovering collapsed stocks of Nassau grouper. Importantly, the government also partnered with academic and nonprofit organizations to establish a research and monitoring program (Grouper Moon) aimed at documenting the impacts of conservation action. Here, we develop an integrated population model of 2 Cayman Nassau grouper stocks based on both diver-collected mark-resight observations and video censuses. Using both data types across multiple years, we fit parameters for a state-space model for population growth. We show that over the last 15 y the Nassau grouper population on Little Cayman has more than tripled in response to conservation efforts. Census data from Cayman Brac, while more sparse, show a similar pattern. These findings demonstrate that spatial and seasonal closures aimed at rebuilding aggregation-based fisheries can foster conservation success.


Asunto(s)
Lubina/fisiología , Conservación de los Recursos Naturales , Animales , Conservación de los Recursos Naturales/métodos , Conservación de los Recursos Naturales/estadística & datos numéricos , Monitoreo del Ambiente , Explotaciones Pesqueras , Peces/fisiología , Modelos Biológicos , Océanos y Mares , Densidad de Población , Encuestas y Cuestionarios , Indias Occidentales
14.
Psychol Health Med ; 28(6): 1411-1420, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35686310

RESUMEN

The COVID-19 pandemic has caused increased anxiety among medical students due to the uncertainty of the long-term effects on the future of medical education. There are currently insufficient studies aimed at investigating the changes in the mental health and studying habits of medical students during public health emergencies such as this pandemic, as well as methods that can be incorporated to appropriately manage anxiety effectively. To investigate the psychological impact and associated factors on medical students during the pandemic. This retrospective, cross-sectional study consisted of 291 medical students of the faculty of medical sciences at the university of the West Indies, St. Augustine campus, Trinidad and Tobago. The mental health and study habits of said students were assessed with the use of questionnaires via an online survey platform. Data of our study showed that 56% of the students were experiencing increased stress and anxiety. Students of 82.8% experienced irregular sleeping habits and 76.3% of participants experienced a change in eating habits brought on by the pandemic. Participants of 67.4% studied less than 4 hrs. a day, 61.5% were less productive, 62.2% showed an inability to focus and avoid distractions in their study environment during the COVID-19 pandemic. There is a need for proper supportive strategies to assist students in effectively managing anxiety and depression during public health emergencies such as COVID-19. It is suggested that all universities, colleges and education bodies alike implement a pandemic preparedness course as well as an accessible online support forum.


Asunto(s)
COVID-19 , Estudiantes de Medicina , Humanos , COVID-19/epidemiología , Salud Mental , Pandemias , Estudios Transversales , Urgencias Médicas , Estudios Retrospectivos , Indias Occidentales/epidemiología , Hábitos
15.
J Zoo Wildl Med ; 54(2): 332-335, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37428696

RESUMEN

The endemic Grand Cayman or blue iguana (Cyclura lewisi) is endangered. Beginning in 2015 significant morbidity and mortality occurred in captive and wild blue iguanas within Grand Cayman's Queen Elizabeth II Botanic Park (QEIIBP). Investigation identified a novel Helicobacter sp., provisionally named Helicobacter sp. Grand Cayman Blue Iguana 1 (GCBI1), as the cause. Invasive green iguanas (Iguana iguana) are believed to play a role in GCBI1 transmission to the blue iguana; however, the origin and transmission pathways have not been determined. To assess the likelihood of blue iguanas asymptomatically harboring GCBI1, in May 2022 population-level screening of captive blue iguanas at QEIIBP was conducted on half (n = 102) of the captive blue iguana population (n = 201) including half of each age class. Helicobacter sp. GCBI1 is closely related to a chelonian Helicobacter sp. and 10 sympatric wild north Antillean sliders (Trachemys decussata angusta) were sampled in October 2019. Combined choana/cloacal swabs were screened by a GCBI1-specific quantitative polymerase chain reaction (qPCR) assay. All samples were negative, suggesting that GCBI1 is not present asymptomatically in the captive blue iguana population or in north Antillean sliders. These results provide support for the hypothesis that GCBI1 is periodically introduced to captive and wild blue iguanas from another species or source.


Asunto(s)
Caimanes y Cocodrilos , Iguanas , Animales , Indias Occidentales/epidemiología
16.
Ecol Lett ; 25(11): 2384-2396, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36192673

RESUMEN

Ecological community structure ultimately depends on the production of community members by speciation. To understand how macroevolution shapes communities, we surveyed Anolis lizard assemblages across elevations on Jamaica and Hispaniola, neighbouring Caribbean islands similar in environment, but contrasting in the richness of their endemic evolutionary radiations. The impact of diversification on local communities depends on available spatial opportunities for speciation within or between ecologically distinct sub-regions. In the spatially expansive lowlands of both islands, communities converge in species richness and average morphology. But communities diverge in the highlands. On Jamaica, where limited highland area restricted diversification, communities remain depauperate and consist largely of elevational generalists. In contrast, a unique fauna of high-elevation specialists evolved in the vast Hispaniolan highlands, augmenting highland richness and driving islandwide turnover in community composition. Accounting for disparate evolutionary opportunities may illuminate when regional diversity will enhance local diversity and help predict when communities should converge in structure.


Asunto(s)
Lagartos , Animales , Lagartos/genética , Evolución Biológica , Biota , Indias Occidentales , Filogenia
17.
Mol Biol Evol ; 38(1): 84-95, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33035304

RESUMEN

Reconstructing the evolutionary history of island biotas is complicated by unusual morphological evolution in insular environments. However, past human-caused extinctions limit the use of molecular analyses to determine origins and affinities of enigmatic island taxa. The Caribbean formerly contained a morphologically diverse assemblage of caviomorph rodents (33 species in 19 genera), ranging from ∼0.1 to 200 kg and traditionally classified into three higher-order taxa (Capromyidae/Capromyinae, Heteropsomyinae, and Heptaxodontidae). Few species survive today, and the evolutionary affinities of living and extinct Caribbean caviomorphs to each other and to mainland taxa are unclear: Are they monophyletic, polyphyletic, or paraphyletic? We use ancient DNA techniques to present the first genetic data for extinct heteropsomyines and heptaxodontids, as well as for several extinct capromyids, and demonstrate through analysis of mitogenomic and nuclear data sets that all sampled Caribbean caviomorphs represent a well-supported monophyletic group. The remarkable morphological and ecological variation observed across living and extinct caviomorphs from Cuba, Hispaniola, Jamaica, Puerto Rico, and other islands was generated through within-archipelago evolutionary radiation following a single Early Miocene overwater colonization. This evolutionary pattern contrasts with the origination of diversity in many other Caribbean groups. All living and extinct Caribbean caviomorphs comprise a single biologically remarkable subfamily (Capromyinae) within the morphologically conservative living Neotropical family Echimyidae. Caribbean caviomorphs represent an important new example of insular mammalian adaptive radiation, where taxa retaining "ancestral-type" characteristics coexisted alongside taxa occupying novel island niches. Diversification was associated with the greatest insular body mass increase recorded in rodents and possibly the greatest for any mammal lineage.


Asunto(s)
ADN Antiguo/análisis , Roedores/genética , Animales , Filogeografía , Indias Occidentales
18.
Mol Phylogenet Evol ; 175: 107558, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35772621

RESUMEN

Understanding the evolution of the tribe Gochnatieae (Compositae) has been the subject of considerable effort in the past decade. This is due to the key position of this tribe in the phylogeny of the sunflower family and the corresponding implications for biogeographic and morphological evolution of Compositae. Previous studies have confirmed the monophyly of this tribe as well as most of the genera that belong to it. However, phylogenetic resolution of Gochnatieae at both the genus- and species-level has remained poor. A subset of new phylogenomic loci used in this study has proven effective and has improved phylogenetic resolution in this group. The results of this work demonstrate Gochnatieae is a well-supported clade comprised of nine genera (Anastraphia, Cnicothamnus, Cyclolepis, Gochnatia, Moquiniastrum, Nahuatlea, Pentaphorus, Richterago, Tehuasca). One recently described genus, Vickia, was not included in this study; but its placement in Gochnatieae as a tenth genus in the tribe is well-justified. The monospecific Cyclolepis, which had been circumscribed within the tribe since its inception but was subsequently removed and designated as incertae sedis since 2014, is also shown to belong to Gochnatieae. We confirmed the monophyletic Moquiniastrum with two well-supported subclades. Ancestral area reconstruction analyses show that Gochnatieae originated in Eastern South America about 53 my. Apparently, except for Cyclolepis and Richterago, the ancestors of the other genera of Gochnatieae originated about 44 my from an area that now corresponds to the central Andes. The presence of the genera in the Chaco phytogeographic province, central Chile, and Mexico-United States-Caribbean is a result of dispersal from the central Andes. The ancestral distribution of Moquiniastrum corresponds to a large area comprising Eastern South America and the current central Andes, about 32 my. Ancestral character state reconstruction that included four characters indicates several states associated with complex plant reproductive biology such as gynodioecy, gynomonoecy, and polygamodioecy are derived in Gochnatieae as are heterogamous capitula (in Moquiniastrum and Richterago), dimorphic and subdimorphic corollas (in Cnicothamnus, Moquiniastrum, and Richterago), and the presence of marginal female corollas (in Moquiniastrum and Richterago). Within Moquiniastrum, two subclades (Densicephalum and Polymorphum) exhibit divergent patterns of trait evolution associated with these reproductive characters which suggests this genus can serve as a model to understand the sexual system evolution in plants.


Asunto(s)
Asteraceae , Región del Caribe , Chile , Filogenia , Indias Occidentales
19.
Mol Phylogenet Evol ; 174: 107548, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35690377

RESUMEN

The genus Cyclura includes nine extant species and six subspecies of West Indian Rock Iguanas and is one of the most imperiled genera of squamate reptiles globally. An understanding of species diversity, evolutionary relationships, diversification, and historical biogeography in this group is crucial for implementing sound long-term conservation strategies. We collected DNA samples from 1 to 10 individuals per taxon from all Cyclura taxa (n = 70 ingroup individuals), focusing where possible on incorporating individuals from different populations of each species. We also collected 1-2 individuals from each of seven outgroup species of iguanas (Iguana delicatissima; five Ctenosaura species) and Anolis sagrei (n = 12 total outgroup individuals). We used targeted genomic sequence capture to isolate and to sequence 1,872 loci comprising of 687,308 base pairs (bp) from each of the 82 individuals from across the nuclear genome. We extracted mitochondrial reads and assembled and annotated mitogenomes for all Cyclura taxa plus outgroup species. We present well-supported phylogenomic gene tree/species tree analyses for all extant species of Cyclura using ASTRAL-III, SVDQuartets, and StarBEAST2 methods, and discuss the taxonomic, biogeographic, and conservation implications of these data. We find a most recent common ancestor of the genus 9.91 million years ago. The earliest divergence within Cyclura separates C. pinguis from a clade comprising all other Cyclura. Within the latter group, a clade comprising C. carinata from the southern Lucayan Islands and C. ricordii from Hispaniola is the sister taxon to a clade comprising the other Cyclura. Among the other Cyclura, the species C. cornuta and C. stejnegeri (from Hispaniola and Isla Mona) form the sister taxon to a clade of species from Jamaica (C. collei), Cuba and Cayman Islands (C. nubila and C. lewisi), and the eastern (C. rileyi) and western (C. cychlura) Lucayan Islands. Cyclura cychlura and C. rileyi form a clade whose sister taxa are C. nubila and C. lewisi. Cyclura collei is the sister taxon to these four species combined.


Asunto(s)
Iguanas , Lagartos , Animales , Cuba , Humanos , Iguanas/genética , Lagartos/genética , Filogenia , Análisis de Secuencia de ADN , Indias Occidentales
20.
BMC Cancer ; 22(1): 783, 2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-35843938

RESUMEN

BACKGROUND: Geographical disparities in cancer incidence are observed at different scales and may highlight areas of high risk that need special attention to improve health policies. In Guadeloupe, a French archipelago in the Caribbean, environmental and socioeconomic factors are potential factors associated with cancer incidence. Our objective was to describe geographical variations of cancer incidence in Guadeloupe at a small-area level, in order to identify potential clusters. METHODS: We conducted spatial analyses for the 18 most frequent cancer sites, using data collected by the population-based cancer registry of Guadeloupe over the period 2008-2017. For each cancer sites, we used the Besag, York and Mollié model to estimate smoothed standardized incidence ratios (SIRs) at a sub-municipality level. In addition, we performed ascendant hierarchical clustering of these smoothed SIRs to describe the relationship between the different cancer sites and to identify geographical clusters. RESULTS: We observed geographical disparities with a spatial pattern that varied across cancer sites. Clustering of the smoothed SIRs showed aggregations between breast cancer and multiple myeloma, thyroid and stomach cancer, cervical and head and neck cancers, lung and rectal cancers, ovarian and endometrial cancers. Cluster analysis also identified six geographical clusters. Features of these clusters suggest alcohol consumption, exposure to pesticides, pollution generated by open landfills, and ethnicity as possible explanatory factors. DISCUSSION/CONCLUSION: Our study provided for the first time an extensive description of geographical disparities in cancer incidence in Guadeloupe, in a region where socioeconomic and environmental issues are major concerns. Although the identification of underlying factors was out of the scope of the present study, we highlighted areas of special interest and put forward some hypotheses that warrant to be further investigated in more in-depth analyses.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/epidemiología , Análisis por Conglomerados , Femenino , Guadalupe/epidemiología , Humanos , Incidencia , Indias Occidentales
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