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1.
Proc Biol Sci ; 291(2026): 20240778, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38955231

RESUMEN

Mammals influence nearly all aspects of energy flow and habitat structure in modern terrestrial ecosystems. However, anthropogenic effects have probably altered mammalian community structure, raising the question of how past perturbations have done so. We used functional diversity (FD) to describe how the structure of North American mammal palaeocommunities changed over the past 66 Ma, an interval spanning the radiation following the K/Pg and several subsequent environmental disruptions including the Palaeocene-Eocene Thermal Maximum (PETM), the expansion of grassland, and the onset of Pleistocene glaciation. For 264 fossil communities, we examined three aspects of ecological function: functional evenness, functional richness and functional divergence. We found that shifts in FD were associated with major ecological and environmental transitions. All three measures of FD increased immediately following the extinction of the non-avian dinosaurs, suggesting that high degrees of ecological disturbance can lead to synchronous responses both locally and continentally. Otherwise, the components of FD were decoupled and responded differently to environmental changes over the last ~56 Myr.


Asunto(s)
Biodiversidad , Fósiles , Mamíferos , Animales , Mamíferos/fisiología , América del Norte , Ecosistema , Evolución Biológica
2.
Parasite ; 31: 29, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38860920

RESUMEN

A parasitological investigation of Cyprinella venusta and Notropis cf. stramineus sampled in Texas, USA, in the Guadalupe River, revealed the presence of Gyrodactylus crysoleucas Mizelle and Kritsky, 1967 on C. venusta, and Gyrodactylus mediotorus King, Marcogliese, Forest, McLaughlin & Bentzen, 2013 on both fish species. This represents new leuscicid fish hosts and locality records for these two gyrodactylids. Gyrodactylus crysoleucas previously identified from both non-native Californian Notemigonus crysoleucas and from farmed stocks in Minnesota demonstrated intraspecific variability in terms of morphology and genetics as a local adaptation associated with isolation by distance. Results further confirmed G. crysoleucas as alien in the western USA and suggested host-switching involving C. venusta and N. crysoleucas. Conservative morphology and genetics on the part of G. mediotorus from C. venusta and N. cf. stramineus (Guadalupe River) was observed, while higher genetic divergence in the ITS sequences associated with morphological discrepancy was found between the studied G. mediotorus specimens and those of Notropis hudsonius than when considering the parasites of Notropis texanus. The separation of G. mediotorus into geographical subgroups may indicate ongoing speciation linked to the Pleistocene glaciations in North America, and to hydrographic barriers that facilitated separate evolutionary paths leading to speciation. We suggest that deep investigations of Gyrodactylus populations will help to understand the speciation of these parasites and their adaptation to Nearctic fish hosts.


Title: Variation intraspécifique chez Gyrodactylus mediotorus et G. crysoleucas (Gyrodactylidae), parasites de ménés néarctiques (Leuciscidae) : preuves d'une spéciation en cours, d'un changement d'hôte et d'une translocation de parasites. Abstract: Une enquête parasitologique sur Cyprinella venusta et Notropis cf. stramineus échantillonnés au Texas, États-Unis, dans la rivière Guadalupe, a révélé la présence de Gyrodactylus crysoleucas Mizelle et Kritsky, 1967 sur C. venusta, et de Gyrodactylus mediotorus King, Marcogliese, Forest, McLaughlin & Bentzen, 2013 sur les deux espèces de poissons. Ceci représente de nouveaux poissons Leuciscidae hôtes et des nouvelles localités pour ces deux Gyrodactylidae. Gyrodactylus crysoleucas, identifié précédemment à partir de Notemigonus crysoleucas californiens non indigènes et de stocks d'élevage du Minnesota a démontré une variabilité intraspécifique en termes de morphologie et de génétique en tant qu'adaptation locale associée à l'isolement par la distance. Les résultats ont en outre confirmé que G. crysoleucas était exotique dans l'ouest des États-Unis et ont suggéré un changement d'hôte impliquant C. venusta et N. crysoleucas. Une morphologie et une génétique conservatrices pour G. mediotorus de C. venusta et N. cf. stramineus (rivière Guadalupe) ont été observées, tandis qu'une divergence génétique plus élevée dans les séquences ITS, associée à une divergence morphologique, a été trouvée chez les spécimens étudiés de G. mediotorus et de Notropis hudsonius lorsque l'on considère les parasites de Notropis texanus. La séparation de G. mediotorus en sous-groupes géographiques peut indiquer une spéciation continue liée aux glaciations du Pléistocène en Amérique du Nord et à des barrières hydrographiques qui ont facilité des chemins évolutifs séparés menant à la spéciation. Nous suggérons que des études approfondies sur les populations de Gyrodactylus aideront à comprendre la spéciation de ces parasites et leur adaptation aux poissons hôtes néarctiques.


Asunto(s)
Enfermedades de los Peces , Infecciones por Trematodos , Animales , Enfermedades de los Peces/parasitología , Infecciones por Trematodos/parasitología , Infecciones por Trematodos/veterinaria , Texas , Ríos/parasitología , Variación Genética , Trematodos/clasificación , Trematodos/genética , Trematodos/anatomía & histología , Trematodos/aislamiento & purificación , Especiación Genética , Cyprinidae/parasitología , Filogenia , Especificidad del Huésped , Interacciones Huésped-Parásitos
3.
Int J Neonatal Screen ; 10(2)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38920845

RESUMEN

Newborn bloodspot screening (NBS) began in the early 1960s based on the work of Dr. Robert "Bob" Guthrie in Buffalo, NY, USA. His development of a screening test for phenylketonuria on blood absorbed onto a special filter paper and transported to a remote testing laboratory began it all. Expansion of NBS to large numbers of asymptomatic congenital conditions flourishes in many settings while it has not yet been realized in others. The need for NBS as an efficient and effective public health prevention strategy that contributes to lowered morbidity and mortality wherever it is sustained is well known in the medical field but not necessarily by political policy makers. Acknowledging the value of national NBS reports published in 2007, the authors collaborated to create a worldwide NBS update in 2015. In a continuing attempt to review the progress of NBS globally, and to move towards a more harmonized and equitable screening system, we have updated our 2015 report with information available at the beginning of 2024. Reports on sub-Saharan Africa and the Caribbean, missing in 2015, have been included. Tables popular in the previous report have been updated with an eye towards harmonized comparisons. To emphasize areas needing attention globally, we have used regional tables containing similar listings of conditions screened, numbers of screening laboratories, and time at which specimen collection is recommended. Discussions are limited to bloodspot screening.

4.
Animals (Basel) ; 14(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38929405

RESUMEN

Avian metapneumovirus (aMPV) has been identified as an important cause of respiratory and reproductive disease, leading to significant productive losses worldwide. Different subtypes have been found to circulate in different regions, with aMPV-A and B posing a significant burden especially in the Old World, and aMPV-C in North America, albeit with limited exceptions of marginal economic relevance. Recently, both aMPV-A and aMPV-B have been reported in the U.S.; however, the route of introduction has not been investigated. In the present study, the potential importation pathways have been studied through phylogenetic and phylodynamic analyses based on a broad collection of partial attachment (G) protein sequences collected worldwide. aMPV-B circulating in the U.S. seems the descendant of Eastern Asian strains, which, in turn, are related to European ones. A likely introduction pathway mediated by wild bird migration through the Beringian crucible, where the East Asian and Pacific American flight paths intersect, appears likely and was previously reported for avian influenza. aMPV-A, on the other hand, showed a Mexican origin, involving strains related to Asian ones. Given the low likelihood of trade or illegal importation, the role of wild birds appears probable also in this case, since the region is covered by different flight paths directed in a North-South direction through America. Since the information on the role of wild birds in aMPV epidemiology is still scarce and scattered, considering the significant practical implications for the poultry industry demonstrated by recent U.S. outbreaks, further surveys on wild birds are encouraged.

5.
Harm Reduct J ; 21(1): 92, 2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734643

RESUMEN

BACKGROUND: Mortality related to opioid overdose in the U.S. has risen sharply in the past decade. In California, opioid overdose death rates more than tripled from 2018 to 2021, and deaths from synthetic opioids such as fentanyl increased more than seven times in those three years alone. Heightened attention to this crisis has attracted funding and programming opportunities for prevention and harm reduction interventions. Drug checking services offer people who use drugs the opportunity to test the chemical content of their own supply, but are not widely used in North America. We report on qualitative data from providers and clients of harm reduction and drug checking services, to explore how these services are used, experienced, and considered. METHODS: We conducted in-depth semi-structured key informant interviews across two samples of drug checking stakeholders: "clients" (individuals who use drugs and receive harm reduction services) and "providers" (subject matter experts and those providing clinical and harm reduction services to people who use drugs). Provider interviews were conducted via Zoom from June-November, 2022. Client interviews were conducted in person in San Francisco over a one-week period in November 2022. Data were analyzed following the tenets of thematic analysis. RESULTS: We found that the value of drug checking includes but extends well beyond overdose prevention. Participants discussed ways that drug checking can fill a regulatory vacuum, serve as a tool of informal market regulation at the community level, and empower public health surveillance systems and clinical response. We present our findings within three key themes: (1) the role of drug checking in overdose prevention; (2) benefits to the overall agency, health, and wellbeing of people who use drugs; and (3) impacts of drug checking services at the community and systems levels. CONCLUSION: This study contributes to growing evidence of the effectiveness of drug checking services in mitigating risks associated with substance use, including overdose, through enabling people who use and sell drugs to test their own supply. It further contributes to discussions around the utility of drug checking and harm reduction, in order to inform legislation and funding allocation.


Asunto(s)
Reducción del Daño , Humanos , Femenino , Investigación Cualitativa , Masculino , Sobredosis de Opiáceos/prevención & control , Adulto , San Francisco , Consumidores de Drogas , Trastornos Relacionados con Opioides/prevención & control , Sobredosis de Droga/prevención & control
7.
J Microsc ; 294(3): 420-439, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38747464

RESUMEN

In September 2023, the two largest bioimaging networks in the Americas, Latin America Bioimaging (LABI) and BioImaging North America (BINA), came together during a 1-week meeting in Mexico. This meeting provided opportunities for participants to interact closely with decision-makers from imaging core facilities across the Americas. The meeting was held in a hybrid format and attended in-person by imaging scientists from across the Americas, including Canada, the United States, Mexico, Colombia, Peru, Argentina, Chile, Brazil and Uruguay. The aims of the meeting were to discuss progress achieved over the past year, to foster networking and collaborative efforts among members of both communities, to bring together key members of the international imaging community to promote the exchange of experience and expertise, to engage with industry partners, and to establish future directions within each individual network, as well as common goals. This meeting report summarises the discussions exchanged, the achievements shared, and the goals set during the LABIxBINA2023: Bioimaging across the Americas meeting.

8.
Glob Chang Biol ; 30(5): e17298, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38712640

RESUMEN

Diversified crop rotations have been suggested to reduce grain yield losses from the adverse climatic conditions increasingly common under climate change. Nevertheless, the potential for climate change adaptation of different crop rotational diversity (CRD) remains undetermined. We quantified how climatic conditions affect small grain and maize yields under different CRDs in 32 long-term (10-63 years) field experiments across Europe and North America. Species-diverse and functionally rich rotations more than compensated yield losses from anomalous warm conditions, long and warm dry spells, as well as from anomalous wet (for small grains) or dry (for maize) conditions. Adding a single functional group or crop species to monocultures counteracted yield losses from substantial changes in climatic conditions. The benefits of a further increase in CRD are comparable with those of improved climatic conditions. For instance, the maize yield benefits of adding three crop species to monocultures under detrimental climatic conditions exceeded the average yield of monocultures by up to 553 kg/ha under non-detrimental climatic conditions. Increased crop functional richness improved yields under high temperature, irrespective of precipitation. Conversely, yield benefits peaked at between two and four crop species in the rotation, depending on climatic conditions and crop, and declined at higher species diversity. Thus, crop species diversity could be adjusted to maximize yield benefits. Diversifying rotations with functionally distinct crops is an adaptation of cropping systems to global warming and changes in precipitation.


Asunto(s)
Cambio Climático , Productos Agrícolas , Zea mays , Productos Agrícolas/crecimiento & desarrollo , Zea mays/crecimiento & desarrollo , América del Norte , Europa (Continente) , Grano Comestible/crecimiento & desarrollo , Agricultura/métodos , Biodiversidad , Producción de Cultivos/métodos
9.
Integr Zool ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38601992

RESUMEN

Traditional Dipodomys (sub)species identification uses geography, phenotype, and external/skull measurements. Such measurements are correlated with size and thus redundant. I assessed the value of scaled cranial shape, based on two-dimensional landmarks (analyzed using geometric morphometric methods) in distinguishing Dipodomys taxa, and in summarizing their variation. My dataset includes 601 adult specimens from 20 species (49 operational taxonomic units - OTUs) across 190 localities. Cranial shape was highly useful in classifying Dipodomys taxa without considering geography. The auditory bulla was the most variable region-taxa differed in its hypertrophy, accompanied by different degrees of nearby structure crowding. Cranial shape was weakly allometric, with no significant sexual dimorphism. Weak size dimorphism was detected. (Sub)specific taxonomy is not reflective of shape variation, as the number of subspecies per species is not associated with disparity. Shape had significant phylogenetic signal, but subspecies did not always cluster with conspecifics and species did not always cluster according to phylogenetic relationship/taxonomy. Shape variation was correlated with climate, and species differed in morphological disparity and degree of specialization, which may contribute to divergence in shape variation patterns from phylogeny. D. deserti was the most specialized species, diverging greatly from the genus mean; D. heermanni was the least specialized. This study provides new insights into morphological variation of North American keystone species, several of conservation interest, for example, D. heermanni berkeleyensis, D. h. dixoni, D. nitratoides brevinasus, and D. n. nitratoides.

10.
Sci Rep ; 14(1): 7893, 2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570549

RESUMEN

The Anthropocene rise in global temperatures is facilitating the expansion of tropical species into historically non-native subtropical locales, including coral reef fish. This redistribution of species, known as tropicalization, has serious consequences for economic development, livelihoods, food security, human health, and culture. Measuring the tropicalization of subtropical reef fish assemblages is difficult due to expansive species ranges, temporal distribution shifts with the movement of isotherms, and many dynamic density-dependent factors affecting occurrence and density. Therefore, in locales where tropical and subtropical species co-occur, detecting tropicalization changes relies on regional analyses of the relative densities and occurrence of species. This study provides a baseline for monitoring reef fish tropicalization by utilizing extensive monitoring data from a pivotal location in southeast Florida along a known transition between tropical and subtropical ecotones to define regional reef fish assemblages and use benthic habitat maps to spatially represent their zoogeography. Assemblages varied significantly by ecoregion, habitat depth, habitat type, and topographic relief. Generally, the southern assemblages had higher occurrences and densities of tropical species, whereas the northern assemblages had a higher occurrence and density of subtropical species. A total of 108 species were exclusive to regions south of the Bahamas Fracture Zone (BFZ) (South Palm Beach, Deerfield, Broward-Miami) and 35 were exclusive to the north (North Palm Beach, Martin), supporting the BFZ as a pivotal location that affects the coastal biogeographic extent of tropical marine species in eastern North America. Future tropicalization of reef fish assemblages are expected to be evident in temporal deviance of percent occurrence and/or relative species densities between baseline assemblages, where the poleward expansion of tropical species is expected to show the homogenization of assemblage regions as adjacent regions become more similar or the regional boundaries expand poleward. Ecoregions, habitat depth, habitat type, and relief should be incorporated into the stratification and analyses of reef fish surveys to statistically determine assemblage differences across the seascape, including those from tropicalization.


Asunto(s)
Arrecifes de Coral , Fracturas Óseas , Animales , Humanos , Ecosistema , Peces , Florida , Bahamas
11.
Sci Rep ; 14(1): 9041, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38641589

RESUMEN

Monitoring methane emissions is crucial in mitigating climate change as it has a relatively short atmospheric lifetime of about 12 years and a significant radiative forcing impact. To measure the impact of methane-controlling policies and techniques, a deep understanding of methane emissions is of great importance. Remote sensing offers scalable approaches for monitoring methane emissions at various scales, from point-source high-resolution monitoring to regional and global estimates. The TROPOMI satellite instrument provides daily XCH4 data globally, offering the opportunity to monitor methane at a moderate spatial resolution with an acceptable level of sensitivity. To infer emissions from TROPOMI data, we used the prior emission estimates from global and national inventories and the GEOS-Chem chemical transport model to simulate atmospheric methane along with actual observations of TROPOMI. In this study, methane emissions from Toronto, Montreal, New York, Los Angeles, Houston, and Mexico City have been estimated using the analytical solution of Bayesian inversion using the cloud-based Integrated Methane Inversion (IMI) framework. Using the result from ensemble inversions, and city boundaries, the average total emissions were as follows: Toronto 230.52 Gg a-1, Montreal 111.54 Gg a-1, New York 144.38 Gg a-1, Los Angeles 207.03 Gg a-1, Houston 650.16 Gg a-1, and Mexico City 280.81 Gg a-1. The resulting gridded scale factors ranged from 0.22 to 6.2, implying methane prior emission underestimations in most of these cities. As such, this study underscores the key role of remote sensing in accurately assessing urban methane emissions, informing essential climate mitigation efforts.

12.
Folia Parasitol (Praha) ; 712024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38567406

RESUMEN

Morphological data are used to describe a new nematode species, Heterocheilus floridensis sp. n. (Heterocheilidae) from the digestive tract of the Florida manatee Trichechus manatus latirostris (Harlan) (Trichechidae, Sirenia) from Florida, USA. Examination by light and scanning electron microscopy revealed that the new species differs from the related Heterocheilus tunicatus Diesing, 1839 mainly by having dentigerous ridges on the inner surface of the lips, a median unpaired papilla located anterior to the cloaca, and a considerably larger body size. Sequence data for subunits I and II of mitochondrial cytochrome oxidase gene, 18S small subunit and 28S ribosomal RNA genes were provided for molecular characterisation of the new species. However, the current unavailability of homologous sequence data for congeneric specimens precluded a molecular assessment of the morphological species hypothesis, and ascaridoid phylogenetic hypotheses could not be advanced. Specimens of Heterocheilus sp. collected from the Antillean manatee Trichechus manatus manatus Linnaeus in Puerto Rico, on loan from the US National Museum of Natural History, were morphologically consistent with the new species, so apparently all congeneric nematodes reported from both subspecies of the West Indian manatee Trichechus manatus Linnaeus and previously identified as H. tunicatus belong rather to H. floridensis sp. n. Heterocheilus hagenbecki (Khalil et Vogelsang, 1932) Sprent 1980 is here considered to be a species inquirenda. A key to valid species of Heterocheilus Diesing, 1839 is provided.


Asunto(s)
Nematodos , Trichechus manatus , Animales , Sirenia , Filogenia
13.
J Med Entomol ; 61(3): 595-602, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38431876

RESUMEN

Vector-borne disease incidence and burden are on the rise. Weather events and climate patterns are known to influence vector populations and disease distribution and incidence. Changes in weather trends and climatic factors can shift seasonal vector activity and host behavior, thus altering pathogen distribution and introducing diseases to new geographic regions. With the upward trend in global temperature, changes in the incidence and distribution of disease vectors possibly linked to climate change have been documented. Forecasting and modeling efforts are valuable for incorporating climate into predicting changes in vector and vector-borne disease distribution. These predictions serve to optimize disease outbreak preparedness and response. The purpose of this scoping review was to describe the use of climate data in vector-borne disease prediction in North America between 2000 and 2022. The most investigated diseases were West Nile virus infection, Lyme disease, and dengue. The uneven geographical distribution of publications could suggest regional differences in the availability of surveillance data required for vector-borne disease predictions and forecasts across the United States, Canada, and Mexico. Studies incorporated environmental data from ground-based sources, satellite data, previously existing data, and field-collected data. While environmental data such as meteorological and topographic factors were well-represented, further research is warranted to ascertain if relationships with less common variables, such as oceanographic characteristics and drought, hold among various vector populations and throughout wider geographical areas. This review provides a catalogue of recently used climatic data that can inform future assessments of the value of such data in vector-borne disease models.


Asunto(s)
Cambio Climático , Enfermedades Transmitidas por Vectores , Enfermedades Transmitidas por Vectores/epidemiología , Enfermedades Transmitidas por Vectores/transmisión , América del Norte/epidemiología , Animales , Humanos , Modelos Biológicos , Predicción
14.
J Med Internet Res ; 26: e53437, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38536065

RESUMEN

BACKGROUND: Digital health and telemedicine are potentially important strategies to decrease health care's environmental impact and contribution to climate change by reducing transportation-related air pollution and greenhouse gas emissions. However, we currently lack robust national estimates of emissions savings attributable to telemedicine. OBJECTIVE: This study aimed to (1) determine the travel distance between participants in US telemedicine sessions and (2) estimate the net reduction in carbon dioxide (CO2) emissions attributable to telemedicine in the United States, based on national observational data describing the geographical characteristics of telemedicine session participants. METHODS: We conducted a retrospective observational study of telemedicine sessions in the United States between January 1, 2022, and February 21, 2023, on the doxy.me platform. Using Google Distance Matrix, we determined the median travel distance between participating providers and patients for a proportional sample of sessions. Further, based on the best available public data, we estimated the total annual emissions costs and savings attributable to telemedicine in the United States. RESULTS: The median round trip travel distance between patients and providers was 49 (IQR 21-145) miles. The median CO2 emissions savings per telemedicine session was 20 (IQR 8-59) kg CO2). Accounting for the energy costs of telemedicine and US transportation patterns, among other factors, we estimate that the use of telemedicine in the United States during the years 2021-2022 resulted in approximate annual CO2 emissions savings of 1,443,800 metric tons. CONCLUSIONS: These estimates of travel distance and telemedicine-associated CO2 emissions costs and savings, based on national data, indicate that telemedicine may be an important strategy in reducing the health care sector's carbon footprint.


Asunto(s)
Telemedicina , Viaje , Estados Unidos , Humanos , Telemedicina/estadística & datos numéricos , Telemedicina/métodos , Telemedicina/economía , Viaje/estadística & datos numéricos , Estudios Retrospectivos , Dióxido de Carbono/análisis , Contaminación del Aire , Huella de Carbono/estadística & datos numéricos
15.
Lancet Reg Health Am ; 32: 100706, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38495312

RESUMEN

Tick-borne diseases (TBD) remain prevalent worldwide, and risk assessment of tick habitat suitability is crucial to prevent or reduce their burden. This scoping review provides a comprehensive survey of models and data used to predict I. scapularis distribution and abundance in North America. We identified 4661 relevant primary research articles published in English between January 1st, 2012, and July 18th, 2022, and selected 41 articles following full-text review. Models used data-driven and mechanistic modelling frameworks informed by diverse tick, hydroclimatic, and ecological variables. Predictions captured tick abundance (n = 14, 34.1%), distribution (n = 22, 53.6%) and both (n = 5, 12.1%). All studies used tick data, and many incorporated both hydroclimatic and ecological variables. Minimal host- and human-specific data were utilized. Biases related to data collection, protocols, and tick data quality affect completeness and representativeness of prediction models. Further research and collaboration are needed to improve prediction accuracy and develop effective strategies to reduce TBD.

16.
Int J Parasitol Parasites Wildl ; 23: 100922, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38516639

RESUMEN

The genus Dracunculus contains numerous species of subcutaneous parasites of mammals and reptiles. In North America, there are at least three mammal-infecting species of Dracunculus. Reports of Dracunculus infections have been reported from river otters (Lontra canadensis) since the early 1900s; however, little is known about the species infecting otters or their ecology. Most reports of Dracunculus do not have a definitive species identified because females, the most common sex found due to their larger size and location in the extremities of the host, lack distinguishing morphological characteristics, and few studies have used molecular methods to confirm identifications. Thus, outside of Ontario, Canada, where both D. insignis and D. lutrae have been confirmed in otters, the species of Dracunculus in river otters is unknown. In the current study, molecular characterization of nematodes from river otters revealed a high diversity of Dracunculus species. In addition to confirming D. insignis infections, two new clades were detected. One clade was a novel species in any host and the other was a clade previously detected in Virginia opossums (Didelphis virginiana) from the USA and a domestic dog from Spain. No infections with D. lutrae were detected and neither new lineage was genetically similar to D. jaguape, which was recently described from a neotropical otter (Lontra longicaudis) from Argentina. These data also indicate that Dracunculus spp. infections in otters are widespread throughout Eastern North America. Currently the life cycles for most of the Dracunculus spp. infecting otters are unknown. Studies on the diversity, life cycle, and natural history of Dracunculidae parasites in wildlife are important because the related parasite, D. medinensis (human Guinea worm) is the subject of an international eradication campaign and there are increasing reports of these parasites in new geographic locations and new hosts, including new species in humans and domestic dogs.

17.
Conserv Biol ; 38(2): e14225, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38328897

RESUMEN

Private land protection is an important and growing tool to address biodiversity loss and climate change. Thus, better empirical evidence on the effectiveness of private land protection and organizational practices, such as targeting of lands for protection and choice of protection mechanism (i.e., fee simple land acquisition and conservation easements), is needed. We addressed this gap by estimating the impacts of The Nature Conservancy's (TNC) (a large nongovernmental organization with relatively decentralized management) conservation land acquisitions and easements from 1988 to 2016 in three regions of the United States (Mid-Atlantic, New England and New York, and California). We estimated impact in terms of avoided conversion by comparing natural land cover on 3179 protected parcels with matched unprotected parcels. Nineteen of 21 ecoregional plans used threats of agriculture and development to identify priorities for protection. When regions and protection mechanisms were pooled, on average there was no evidence of avoided conversion from 1988 to 2016. Accounting for mechanisms, TNC land acquisitions avoided conversion and easements did not. TNC's easements on parcels acquired by conservation partners did avoid conversion. Limitations of these results include focus on a single measure of impact, inability to capture future avoided conversion, and low land cover change accuracy in California. Our results suggest that private land protection managers who seek to avoid land conversion in the near to medium term should increase focus on areas with higher threats. Special attention should be paid to strengthening accountability and the role of partners, improving or clarifying how easements are used, and facilitating the flow of resources to work with the greatest potential impact.


Comprensión de la variación en el impacto de las áreas protegidas privadas sobre las regiones y los mecanismos de protección para guiar las prácticas organizativas Resumen La protección de terreno privado es una herramienta importante, aunque su naturaleza voluntaria puede sesgar la protección hacia parcelas menos amenazadas­lo que resulta en que la conversión no se evite o se evite muy poco. Además, muchos programas de protección privada tienen una supervisión limitada y pocos reportes de sus resultados. Por lo tanto, se necesitan mejores evidencias empíricas de la efectividad de la protección en suelo privado y las prácticas organizativas, como el enfoque en tierras para protección y la selección de los mecanismos de protección (adquisición de terrenos a título oneroso y servidumbres de conservación). Abordamos esta brecha con la estimación de impactos de las adquisiciones de suelo de The Nature Conservancy (TNC, una gran organización no gubernamental con un manejo relativamente descentralizado) y las servidumbres implementadas entre 1988 y 2016 en tres regiones de los Estados Unidos: Atlántico Medio, Nueva Inglaterra y Nueva York, y California. Estimamos el impacto en términos de la conversión que se evitó al comparar la cobertura de suelo en 3,179 parcelas protegidas con parcelas desprotegidas equivalentes. Diecinueve de los 21 planes eco­regionales usaron las amenazas a la agricultura y al desarrollo para identificar las prioridades de protección. Cuando agrupamos las regiones y los mecanismos de protección, en promedio no hubo impacto alguno. Si se consideran los mecanismos, las adquisiciones de suelo de la TNC tuvieron un impacto mientras que las servidumbres no. Las servidumbres de la TNC en las parcelas adquiridas por socios de conservación sí tuvieron un impacto, aunque esta manera de proteger sólo se presentó en las regiones del Atlántico Medio y de Nueva Inglaterra y Nueva York. Nuestros resultados sugieren que la protección privada, especialmente mediante servidumbres, puede estar sesgada hacia suelos no amenazados. Los gestores que buscan evitar la conversión del suelo a mediano o corto plazo deberían enfocarse más en las áreas con más amenazas. Se debería prestar especial atención al fortalecimiento del papel y las responsabilidades de los socios, a la mejora o aclaración de cómo se usan las servidumbres y la facilitación del flujo de recursos para trabajar con el mayor impacto potencial.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Estados Unidos , Biodiversidad , Agricultura , Cambio Climático
18.
J Helminthol ; 98: e4, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38167343

RESUMEN

Via molecular and morphological analyses, we describe adult specimens of a new species of Versteria (Cestoda: Taeniidae) infecting mink and river otter (Carnivora: Mustelidae) in Western Canada, as well as larval forms from muskrat and mink. These sequences closely matched those reported from adult specimens from Colorado and Oregon, as well as larval infections in humans and a captive orangutan. We describe here a new species from British Columbia and Alberta (Canada), Versteria rafei n. sp., based upon morphological diagnostic characteristics and genetic distance and phylogeny. Versteria rafei n. sp. differs from the three other described species of the genus in the smaller scolex and cirrus sac. It also differs from V. mustelae (Eurasia) and V. cuja (South America) by having an armed cirrus, which is covered in hair-like bristles, and in the shape of its hooks, with a long thorn-like blade, and short or long handle (vs. a short sharply curved blade and no difference in handle size in previously described species). The poorly known V. brachyacantha (Central Africa) also has an armed cirrus and similarly shaped hooks. However, it differs from the new species in the number and size of hooks. Phylogenetic analysis of the cox1 and nad1 mitochondrial regions showed that our specimens clustered with isolates from undescribed adults and larval infections in North America, and separate from V. cuja, confirming them to be a distinct species from the American Clade.


Asunto(s)
Cestodos , Infecciones por Cestodos , Nutrias , Humanos , Animales , Visón , Filogenia , Alberta
19.
Vet Parasitol ; 327: 110118, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38278035

RESUMEN

Nationwide sampling by Venkatesan and colleagues (2023) described the resistance status of the canine hookworm, Ancylostoma caninum, to benzimidazoles across the USA via ß-tubulin isotype-1 amplicon metabarcoding. In this study, we aimed to use the existing public amplicon metabarcoding data and mine it for the presence of ß-tubulin isotype-1 sequences that belong to hookworm species other than A. caninum. Through bioinformatics analysis we assigned species to A. caninum, Ancylostoma braziliense, Ancylostoma tubaeforme and Uncinaria stenocephala. All non-A. caninum sequences contained only the benzimidazole susceptible residues of ß-tubulin isotype-1. Using two ß-tubulin isotype-1 metabarcoding sequence data (assay targeting 134 and 167 codons, and assay targeting 198 and 200 codons), 2.0% (6/307) and 2.9% (9/310) individual samples had hookworms other than A. caninum (A. braziliense n = 5, A. tubaeforme n = 4 and U. stenocephala n = 2), respectively. We identified one sample containing A. braziliense in each of the Northeastern region and Midwestern region, and in three samples from the Southern region. Presence of A. tubaeforme in dog faeces is considered as pseudoparasitism. There were no statistically significant regional differences for the distribution of each species, for either of the two assays independently or combined (χ2 tests, P > 0.05). Our work demonstrates the utility of the amplicon metabarcoding for the identification of species through antemortem assays, thus resolving the dilemma of assigning hookworm species based on either post-mortem or egg sizes for the identification of hookworms.


Asunto(s)
Ancylostoma , Enfermedades de los Perros , Animales , Perros , Ancylostoma/genética , Ancylostomatoidea/genética , Tubulina (Proteína)/genética , Polimorfismo de Nucleótido Simple , Bencimidazoles , Codón
20.
J Clin Microbiol ; 62(2): e0114123, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38193696

RESUMEN

Azole resistance in Aspergillus fumigatus (AFM) is increasing and often associated with cyp51 alterations. We evaluated the activity of isavuconazole and other mold-active azoles against 731 AFM isolates causing invasive aspergillosis collected in Europe (EU; n = 449) and North America (NA; n = 282). Isolates were submitted to CLSI susceptibility testing and epidemiological cutoff value (ECV) criteria. A posaconazole ECV of 0.5 mg/L was used as no CLSI ECV was determined. Azole non-wild-type (NWT) isolates were submitted for cyp51 sequencing by whole genome sequencing. Overall, isavuconazole activity (92.7%/94.0% WT in EU/NA) was comparable to other azoles (WT rate range, 90.9%-96.4%/91.8%-98.6%, respectively), regardless of the region. A total of 79 (10.8%) azole NWT isolates were detected, and similar rates of these isolates were noted in EU (10.7%) and NA (11.0%). Although most AFM were WT to azoles, increasing azole NWT rates were observed in NA (from 6.0% in 2017 to 29.3% in 2021). Azole NWT rates varied from 4.9% (2019) to 20.6% (2018) in EU without an observed trend. cyp51 alterations occurred in 56.3%/54.8% of azole NWT from EU/NA, respectively. The cyp51A TR34/L98H alteration was observed only in EU isolates (72.0% of EU isolates), while cyp51A I242V occurred only in NA isolates (58.3%). Isavuconazole remained active (MIC, ≤1 mg/L) against 18.5/47.1% of azole NWT AFM exhibiting cyp51 alterations in EU/NA, along with voriconazole (29.6/82.4%; MIC, ≤1 mg/L) and posaconazole (48.1/88.2%; MIC, ≤0.5 mg/L). Fourteen different cyp51 alterations were detected in 44 of 79 NWT isolates. The in vitro activity of the azoles varied in AFM that displayed cyp51 alterations. IMPORTANCE A few microbiology laboratories perform antifungal susceptibility testing locally for systemically active antifungal agents. The identification of emerging azole-resistant Aspergillus fumigatus is worrisome. As such, there is a critical role for antifungal surveillance in tracking emerging resistance among both common and uncommon opportunistic fungi. Differences in the regional prevalence and antifungal resistance of these fungi render local epidemiological knowledge essential for the care of patients with a suspected invasive fungal infection.


Asunto(s)
Aspergillus fumigatus , Infecciones Fúngicas Invasoras , Nitrilos , Piridinas , Triazoles , Humanos , Azoles/farmacología , Antifúngicos/farmacología , Hongos , Europa (Continente)/epidemiología , Farmacorresistencia Fúngica/genética , Pruebas de Sensibilidad Microbiana , Proteínas Fúngicas/genética
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