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1.
Am J Primatol ; 86(5): e23609, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38409820

RESUMEN

The degree of dietary flexibility in primates is species specific; some incorporate a wider array of resources than others. Extreme interannual weather variability in Madagascar results in seasonal resource scarcity which has been linked to specialized behaviors in lemurs. Prolemur simus, for example, has been considered an obligate specialist on large culm bamboo with >60% of its diet composed of woody bamboos requiring morphological and physiological adaptations to process. Recent studies reported an ever-expanding list of dietary items, suggesting that this species may not be an obligate specialist. However, long-term quantitative feeding data are unavailable across this species' range. To explore the dietary flexibility of P. simus, we collected data at two northern sites, Ambalafary and Sahavola, and one southern site, Vatovavy, from September 2010 to January 2016 and May 2017 to September 2018, respectively. In total, we recorded 4022 h of behavioral data using instantaneous sampling of adult males and females from one group in Ambalafary, and two groups each in Sahavola and Vatovavy. We recorded 45 plant species eaten by P. simus over 7 years. We also observed significant differences in seasonal dietary composition between study sites. In Ambalafary, bamboo was the most frequently observed resource consumed (92.2%); however, non-bamboo resources comprised nearly one-third of the diet of P. simus in Sahavola and over 60% in Vatovavy. Consumption of all bamboo resources increased during the dry season at Ambalafary and during the wet season at Vatovavy, but never exceeded non-bamboo feeding at the latter. Culm pith feeding was only observed at Ambalafary, where it was more common during the dry season. We identify P. simus as a bamboo facultative specialist capable of adjusting its feeding behavior to its environment, indicating greater dietary flexibility than previously documented, which may enable the species to survive in increasingly degraded habitats.


Asunto(s)
Lemur , Lemuridae , Femenino , Masculino , Animales , Madagascar , Lemuridae/fisiología , Lemur/fisiología , Conducta Alimentaria/fisiología , Dieta/veterinaria
2.
Sci Total Environ ; 810: 152235, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34890677

RESUMEN

The distribution of bamboo is sensitive to climate change and is also potentially affected by increasing atmospheric CO2 concentrations due to its C3 photosynthetic pathway. Yet the effect of CO2 in climate impact assessments of potential changes in bamboo distribution has to date been overlooked. In this study, we proposed a simple and quantitative method to incorporate the impact of atmospheric CO2 concentration into a species distribution modeling framework. To do so, we implemented 10 niche modeling algorithms with regionally downscaled climatic variables and combined field campaign observations. We assessed future climate impacts on the distribution of an economically and ecologically important and widely distributed bamboo species in Madagascar, and examined the effect of increasing CO2 on future projections. Our results suggested that future climatic changes negatively impact potential bamboo distribution in Madagascar, leading to a decline of 34.8% of climatic suitability and a decline of 63.6 ± 3.2% in suitable areas towards 2100 under RCP 8.5. However, increasing atmosphere CO2 offsets the climate impact for bamboo, and led to a smaller reduction of 19.8% in suitability and a potential distribution expansion of +111.6 ± 9.8% in newly suitable areas. We also found that the decline in climatic suitability for bamboo was related to increasing monthly potential evapotranspiration of the warmest quarter and minimum temperature of the warmest month. Conversely, the decreasing isothermality and increasing precipitation of the warmest quarter contributed to projected increase in bamboo-suitable areas. Our study suggested that elevated CO2 may mitigate the decrease in climatic suitability and increase bamboo-suitable areas, through enhancing water use efficiency and decreasing potential evapotranspiration. Our results highlight the importance of accounting for the CO2 effect on future plant species distributions, and provide a mechanistic approach to do so for ecosystems constrained by water.


Asunto(s)
Cambio Climático , Ecosistema , Dióxido de Carbono , Predicción , Madagascar
3.
Proc Biol Sci ; 288(1957): 20210552, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34403636

RESUMEN

Interactions between hosts and their resident microbial communities are a fundamental component of fitness for both agents. Though recent research has highlighted the importance of interactions between animals and their bacterial communities, comparative evidence for fungi is lacking, especially in natural populations. Using data from 49 species, we present novel evidence of strong covariation between fungal and bacterial communities across the host phylogeny, indicative of recruitment by hosts for specific suites of microbes. Using co-occurrence networks, we demonstrate marked variation across host taxonomy in patterns of covariation between bacterial and fungal abundances. Host phylogeny drives differences in the overall richness of bacterial and fungal communities, but the effect of diet on richness was only evident in the mammalian gut microbiome. Sample type, tissue storage and DNA extraction method also affected bacterial and fungal community composition, and future studies would benefit from standardized approaches to sample processing. Collectively these data indicate fungal microbiomes may play a key role in host fitness and suggest an urgent need to study multiple agents of the animal microbiome to accurately determine the strength and ecological significance of host-microbe interactions.


Asunto(s)
Microbiota , Micobioma , Animales , Bacterias/genética , Interacciones Microbiota-Huesped , Filogenia
4.
Pain ; 161(1): 47-60, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31569141

RESUMEN

Posttraumatic widespread pain (PTWP) and posttraumatic stress symptoms (PTSS) are frequent comorbid sequelae of trauma that occur at different rates in women and men. We sought to identify microRNA (miRNA) that may contribute to sex-dependent differences in vulnerability to these outcomes. Monte Carlo simulations (x10,000) identified miRNA in which predicted targeting of PTWP or PTSS genes was most enriched. Expression of the leading candidate miRNA to target PTWP/PTSS-related genes, miR-19b, has been shown to be influenced by estrogen and stress exposure. We evaluated whether peritraumatic miR-19b blood expression levels predicted PTWP and PTSS development in women and men experiencing trauma of motor vehicle collision (n = 179) and in women experiencing sexual assault trauma (n = 74). A sex-dependent relationship was observed between miR-19b expression levels and both PTWP (ß = -2.41, P = 0.034) and PTSS (ß = -3.01, P = 0.008) development 6 months after motor vehicle collision. The relationship between miR-19b and PTSS (but not PTWP) was validated in sexual assault survivors (ß = -0.91, P = 0.013). Sex-dependent expression of miR-19b was also observed in blood and nervous tissue from 2 relevant animal models. Furthermore, in support of increasing evidence indicating a role for the circadian rhythm (CR) in PTWP and PTSS pathogenesis, miR-19b targets were enriched in CR gene transcripts. Human cohort and in vitro analyses assessing miR-19b regulation of key CR transcripts, CLOCK and RORA, supported the potential importance of miR-19b to regulating the CR pathway. Together, these results highlight the potential role that sex-dependent expression of miR-19b might play in PTWP and PTSS development after trauma/stress exposure.


Asunto(s)
MicroARNs/metabolismo , Dolor/metabolismo , Trastornos por Estrés Postraumático/metabolismo , Accidentes de Tránsito/psicología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Dolor/genética , Dolor/psicología , Factores de Riesgo , Factores Sexuales , Delitos Sexuales/psicología , Trastornos por Estrés Postraumático/genética , Trastornos por Estrés Postraumático/psicología , Adulto Joven
5.
Folia Primatol (Basel) ; 88(6): 507-522, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29393266

RESUMEN

Population viability analysis is a predictive procedure that uses a combination of different modelling approaches to estimate species vulnerability to extinction. Javan gibbons (Hylobates moloch) are vulnerable to local extinction primarily due to loss of habitat and hunting for the illegal pet trade. Using the modelling software VORTEX, we assessed the status of Javan gibbons in 3 areas (Ujung Kulon National Park, Halimun-Salak National Park, and Dieng Mountains) which hold over half of the remaining estimated number of gibbons on Java. Ujung Kulon and Halimun-Salak are long-time protected areas, whereas Dieng Mountains remain unprotected. For each area, we calculated the probability of extinction over a 100-year time period by testing different area-specific scenarios (e.g., hunting, deforestation, and increase in carrying capacity). Our modelling suggests each of the populations has a high chance of becoming extinct within the next 100 years if hunting and deforestation persist. If these threats are eliminated, the model shows each of the populations are large enough to persist in the long term whilst maintaining high levels of current genetic diversity. We conclude that specific actions should be implemented to develop more inclusive conservation management practices, especially improving awareness regarding the illegal wildlife trade and increased protection of wild populations and their habitats.


Asunto(s)
Hylobates/fisiología , Animales , Comercio/legislación & jurisprudencia , Conservación de los Recursos Naturales , Ecosistema , Extinción Biológica , Femenino , Hylobates/crecimiento & desarrollo , Indonesia , Masculino , Modelos Biológicos , Vigilancia de la Población , Programas Informáticos
6.
PLoS One ; 10(3): e0119609, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25811467

RESUMEN

Rehabilitation of animals followed by reintroduction into the wild can benefit conservation by supplementing depleted wild populations or reintroducing a species in an area where it has been extirpated or become extinct. The western lowland gorilla (WLG, Gorilla g. gorilla) is persistently poached; infants are often illegally traded and used as pets. Some are confiscated and rehabilitated, then kept in sanctuaries or reintroduced into the wild. Prior to reintroduction, the ability of the orphans to survive independently in their environment needs to be assessed. Here, we performed a multivariate analysis, including diet composition, activity-budget, and pattern of strata using of a group of five juvenile WLG in the process of rehabilitation and distinguished three sub-periods of ecological significance: the high furgivory period, the Dialium fruits consumption period, and the high folivory period. The consequences of these variations on their well-being (play behaviour) and the group cohesion (spatial proximity and social interactions) were examined. Like wild WLGs, diets shifted seasonally from frugivorous to folivorous, while the same staple foods were consumed and large amounts of Dialium fruits were seasonally gathered high in trees. When succulent fruit intake was the highest, thus providing high energy from sugar, juveniles spent less time feeding, more time playing and group cohesion was the highest. Conversely, the cohesion decreased with increasing folivory, individuals spent more time feeding and less time playing together. Nonetheless, the group cohesion also decreased after the death of one highly social, wild-born orphan. This may underscore the importance of skilled individuals in the cohesion and well-being of the entire group and, ultimately, to rehabilitation success. This study evaluates the rehabilitation success with regards to the methods used and highlights the need to consider a set of individual and environmental factors for enhancing rehabilitation while preserving the local biodiversity and individual well-being.


Asunto(s)
Conducta Animal , Gorilla gorilla , Animales , Gabón , Parques Recreativos
7.
Nucleic Acids Res ; 40(12): 5637-50, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22396527

RESUMEN

Trypanosoma brucei undergoes an essential process of mitochondrial uridine insertion and deletion RNA editing catalyzed by a 20S editosome. The multiprotein mitochondrial RNA-binding complex 1 (MRB1) is emerging as an equally essential component of the trypanosome RNA editing machinery, with additional functions in gRNA and mRNA stabilization. The distinct and overlapping protein compositions of reported MRB1 complexes and diverse MRB1 functions suggest that the complex is composed of subcomplexes with RNA-dependent and independent interactions. To determine the architecture of the MRB1 complex, we performed a comprehensive yeast two-hybrid analysis of 31 reported MRB1 proteins. We also used in vivo analyses of tagged MRB1 components to confirm direct and RNA-mediated interactions. Here, we show that MRB1 contains a core complex comprised of six proteins and maintained by numerous direct interactions. The MRB1 core associates with multiple subcomplexes and proteins through RNA-enhanced or RNA-dependent interactions. These findings provide a framework for interpretation of previous functional studies and suggest that MRB1 is a dynamic complex that coordinates various aspects of mitochondrial gene regulation.


Asunto(s)
Proteínas Mitocondriales/metabolismo , Proteínas Protozoarias/metabolismo , Edición de ARN , Proteínas de Unión al ARN/metabolismo , Trypanosoma brucei brucei/metabolismo , Subunidades de Proteína/metabolismo , ARN Protozoario/metabolismo , Trypanosoma brucei brucei/genética , Técnicas del Sistema de Dos Híbridos
8.
Folia Primatol (Basel) ; 82(2): 118-29, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21952419

RESUMEN

To improve our knowledge of the distribution of the critically endangered greater bamboo lemur Prolemur simus, we surveyed 6 sites in eastern Madagascar. We found its characteristic feeding signs at 5 sites and made a direct sighting at one of these. One site represents a northern extension of 45 km of the known extant range of the species. Two sites are located in a forest corridor approximately halfway between the previously known southern and northern populations, therefore suggesting a broadly continuous distribution of the species within its range rather than the previously suspected distribution of two distinct populations separated by a distance of over 200 km. Our results illustrate the benefit of species-focussed surveys in determining the true distribution of endangered species, a realistic measure which is necessary in order to assess their current status and to prioritise long-term conservation interventions.


Asunto(s)
Especies en Peligro de Extinción , Lemuridae/fisiología , Animales , Conservación de los Recursos Naturales , Conducta Alimentaria , Madagascar , Densidad de Población
9.
J Zoo Wildl Med ; 41(3): 522-5, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20945654

RESUMEN

This brief communication describes the successful treatment of acute systemic anaphylaxis in a wild-born but captive infant western lowland gorilla (Gorilla gorilla gorilla) in the Republic of Congo. The infant demonstrated signs of acute respiratory distress, lingual swelling, and reaction to intradermal tuberculin, given 55 hr earlier. Details of the treatment with steroids, anesthetic induction, and i.v. epinephrine are all reported, and potential antigens that may have initiated the anaphylactic shock are discussed.


Asunto(s)
Anafilaxia/veterinaria , Enfermedades del Simio Antropoideo/tratamiento farmacológico , Gorilla gorilla , Prueba de Tuberculina/veterinaria , Tuberculina/efectos adversos , Anafilaxia/inducido químicamente , Anafilaxia/tratamiento farmacológico , Anestesia/veterinaria , Animales , Antiinflamatorios/uso terapéutico , Enfermedades del Simio Antropoideo/patología , Dexametasona/uso terapéutico , Epinefrina/uso terapéutico , Femenino , Simpatomiméticos/uso terapéutico , Prueba de Tuberculina/efectos adversos
11.
J Org Chem ; 73(9): 3508-15, 2008 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-18351744

RESUMEN

Small molecule TRPV1 antagonists have been a recent focus in the search for pain treatment agents. We herein describe a practical and scalable synthesis of AMG 628 (1), a bis-substituted pyrimidine derivative that was identified as a highly efficacious agent, suitable for clinical development. Highlights of our approach include a practical route to a substituted benzothiazole, a scalable synthesis of an enantiopure piperazine fragment, and identification of conditions for selective coupling reactions on 2,6-dichloropyrimidine, to access the active pharmaceutical ingredient in high purity and overall yield.


Asunto(s)
Canales Catiónicos TRPV/antagonistas & inhibidores , Acetamidas/síntesis química , Acetamidas/química , Benzotiazoles/síntesis química , Benzotiazoles/química , Catálisis , Metales/química , Estructura Molecular , Piperazina , Piperazinas/síntesis química , Piperazinas/química , Pirimidinas/síntesis química , Pirimidinas/química , Estereoisomerismo , Canales Catiónicos TRPV/metabolismo , Tiadiazoles/síntesis química , Tiadiazoles/química
12.
J Org Chem ; 69(25): 8723-30, 2004 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-15575749

RESUMEN

The preparation of 3-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl)propan-1-amine 2a and 3-[(7R)-7-methyl-5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl]propan-1-amine 2b, key intermediates in the synthesis of alpha(V)beta(3) antagonists, is described. The syntheses rely on the efficient double Sonogashira reactions of 2,5-dibromopyridine 3 with acetylenic alcohols 4a/4b and protected propargylamines 10a-e followed by Chichibabin cyclizations of 3,3'-pyridine-2,5-diyldipropan-1-amines 9a/9b.


Asunto(s)
Integrina alfaVbeta3/antagonistas & inhibidores , Naftiridinas/síntesis química , Propano/análogos & derivados , Propano/síntesis química , Estructura Molecular
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