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1.
Cell ; 171(1): 32-33, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28938121

RESUMO

A hallmark of Huntington's disease is the presence of intracellular aggregates of mutant huntingtin, the pathological significance of which has long been debated. Using cryo-electron tomography, Bauerlein et al. reveal the fibrillary structure of huntingtin aggregates in situ and show that huntingtin fibrils interact with the endoplasmic reticulum, distorting its morphology and dynamics.


Assuntos
Proteína Huntingtina , Proteínas do Tecido Nervoso/química , Animais , Retículo Endoplasmático , Humanos , Doença de Huntington , Proteínas Nucleares/química
2.
Nature ; 591(7851): 659-664, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658713

RESUMO

Symmetric cell division requires the even partitioning of genetic information and cytoplasmic contents between daughter cells. Whereas the mechanisms coordinating the segregation of the genome are well known, the processes that ensure organelle segregation between daughter cells remain less well understood1. Here we identify multiple actin assemblies with distinct but complementary roles in mitochondrial organization and inheritance in mitosis. First, we find a dense meshwork of subcortical actin cables assembled throughout the mitotic cytoplasm. This network scaffolds the endoplasmic reticulum and organizes three-dimensional mitochondrial positioning to ensure the equal segregation of mitochondrial mass at cytokinesis. Second, we identify a dynamic wave of actin filaments reversibly assembling on the surface of mitochondria during mitosis. Mitochondria sampled by this wave are enveloped within actin clouds that can spontaneously break symmetry to form elongated comet tails. Mitochondrial comet tails promote randomly directed bursts of movement that shuffle mitochondrial position within the mother cell to randomize inheritance of healthy and damaged mitochondria between daughter cells. Thus, parallel mechanisms mediated by the actin cytoskeleton ensure both equal and random inheritance of mitochondria in symmetrically dividing cells.


Assuntos
Actinas/química , Actinas/metabolismo , Mitocôndrias/metabolismo , Mitose , Citoesqueleto de Actina/química , Citoesqueleto de Actina/metabolismo , Animais , Divisão Celular , Linhagem Celular , Citocinese , Retículo Endoplasmático/metabolismo , Hipocampo/citologia , Hipocampo/embriologia , Humanos , Mitocôndrias/química , Neurônios , Ratos
3.
Proc Natl Acad Sci U S A ; 121(6): e2305944121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38252845

RESUMO

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.


Assuntos
Biodiversidade , Ecossistema , Humanos , Animais , Agricultura , Animais Selvagens , Mudança Climática
4.
Naturwissenschaften ; 111(1): 3, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252296

RESUMO

The Neotropical genus Atelopus is the most diverse genus of bufonids comprising 99 species. Tadpoles of these frogs are readily distinguished based on the presence of a belly sucker, used by them to stay attached to rocks in fast-flowing streams. Despite their intriguing biology, information about their anatomy is scarce and many morphological systems are unknown. We describe the buccopharyngeal cavity of five Atelopus species. The Atelopus buccopharyngeal cavity is characterized by (1) presence of a pendulum-like papillae in the prenarial arena, (2) presence of a glandular zone in the prenarial arena, (3) narial vacuities, (4) conical median ridge, (5) absence of buccal roof arena papillae, (6) absence of buccal roof pustulations, (7) single pair of infralabial papillae, (8) absence of lingual papillae, and (9) absence of pustulations in the buccal floor. We propose that characters 1, 2, and 3 are new synapomorphies for the genus. We also propose that the presence of a single pair of infralabial papillae is a synapomorphy for bufonid. Finally, we discuss the convergent evolution of gastromyzophorous and suctorial tadpoles withing anurans.


Assuntos
Anuros , Bufonidae , Animais , Larva , Filogenia , Rios
5.
Naturwissenschaften ; 111(3): 21, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598027

RESUMO

Frogs of the Allophrynidae are an enigmatic family from South America. To date, published information is lacking regarding this group's reproductive biology and larval morphology. Here, we provide the first detailed description of the reproductive mode, developmental mode, and tadpole morphology for Allophryne ruthveni. We developed a captive breeding and rearing protocol for this species and then conducted a series of observations to describe aspects of its reproductive biology. In captivity, this species exhibits aquatic oviposition, where single eggs are laid ungrouped within a simple jelly capsule and are scattered free in the water column before sinking to develop on benthic substrates. We did not observe parental care nor any parental interactions with eggs post-fertilization. Tadpoles are characterized by an oval body, anteroventral oral disc, a labial tooth row formula of 2(2)/3, and a dextral vent tube. The buccopharyngeal cavity is marked by the presence of two pairs of infralabial papilla and four lingual papillae. Cranial morphology is characterized by the presence of the commissura quadratoorbital. This species possesses an additional slip of the m. rectus cervicis and of the m. levator arcuum branchialium III. We discuss our results in comparison with glassfrogs (Centrolenidae).


Assuntos
Anuros , Reprodução , Feminino , Animais , Oviposição , Larva , Crânio
6.
Am J Primatol ; 86(4): e23598, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38258612

RESUMO

We report on an analytical and biological validation of a commercial cortisol enzyme immunoassay (EIA) to measure glucocorticoids (GC) in feces of Geoffroy's spider monkeys (Ateles geoffroyi). Validation of endocrinological methods for each sample matrix and study species is crucial to establish that the methods produce reliable results. For the analytical validation of the EIA, we assessed parallelism, accuracy, and precision. We carried out a biological validation based on three well-studied GC patterns with the following predictions: (1) increased fecal GC metabolite (fGCM) concentrations after veterinary intervention; (2) increased fGCM concentrations during early morning hours; and (3) higher fGCM concentrations during gestation than in other female reproductive states. For the first prediction, we sampled feces of two zoo-housed females 2 days before, the day of, and 2 days after a veterinary intervention. For the second prediction, we analyzed 284 fecal samples collected from 12 wild males using a linear mixed model (LMM). For the third prediction, we analyzed 269 fecal samples of eight wild females using an LMM. Analytical validation revealed that the EIA showed parallelism, was accurate, and precise within each assay. However, there was elevated variation in between-assay precision. The biological validation supported all predictions: (1) the two zoo-housed females showed a substantial increase in fGCM concentrations 2.5 and 11 h after veterinary intervention; (2) there was a negative effect of sample collection time on fGCM concentrations (i.e., higher concentrations during early morning); (3) gestating females had significantly higher fGCM concentrations than lactating females. Thus, we analytically validated the commercial EIA and, despite between-assay variation, we were able to find three biologically relevant GC signals in captive and wild settings, and in males and females. We are therefore confident that the method can be used to noninvasively address behavioral endocrinology questions in Geoffroy's spider monkeys.


Assuntos
Ateles geoffroyi , Glucocorticoides , Masculino , Animais , Feminino , Glucocorticoides/metabolismo , Lactação , Hidrocortisona , Fezes
7.
Am J Primatol ; 86(8): e23651, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38804875

RESUMO

Leading collective movements and arriving first at feeding sites may improve food acquisition. Specifically, the first individual to discover and exploit a feeding site may gain a feeding advantage known as the "finder's advantage." The aim of this research was to verify if the probability of leading group movements to feeding sites in mantled howler monkeys (Alouatta palliata) varied by sex and reproductive status, and whether finders had higher foraging success than followers. We studied 18 adult individuals from two groups in La Flor de Catemaco over a year (978 h), and sampled group movements (n = 211) and foraging behavior (n = 215 feeding episodes). Gestating females were leaders and finders of group movements to feeding sites more often than expected but were also replaced in the leading position more frequently than individuals of other sex/reproductive states. Feeding behavior was not influenced by the order of arrival at feeding sites per se, but gestating females had higher food intake rate, bite rate, and feeding time when arriving earlier (i.e., occupying front group positions) than later. Therefore, leadership and the finder's advantage occur in this species and are probably employed by gestating females to maintain their energetic condition.


Assuntos
Alouatta , Comportamento Alimentar , Liderança , Animais , Feminino , Masculino , Alouatta/fisiologia , Comportamento Social , Fatores Sexuais
8.
Am J Primatol ; 86(1): e23568, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37850516

RESUMO

Anthropogenic noise is a major global pollutant but its effects on primates are poorly understood, limiting our ability to develop mitigation actions that favor their welfare and conservation. In this study, we used an experimental approach to determine the impact of variation in noise intensity on mantled howler monkeys (Alouatta palliata). We conducted the study at Los Tuxtlas (México), where we studied the physiological stress (proxied via fecal glucocorticoid metabolites, fGCM) and behavioral responses of 16 males. We played back chainsaw noise at two intensities (40 and 80 dB) and used days in which groups were not exposed to noise as matched controls. With increased noise intensity fGCM increased, vigilance and vocalizations were longer, and vigilance, vocalizations, and flight occurred quicker. Physiological and behavioral responses occurred even after low-intensity noise playbacks (i.e., 40 dB). Therefore, noise intensity is a significant factor explaining the responses of mantled howler monkeys to anthropogenic noise. These results imply that management actions aimed at eradicating anthropogenic noise are required for the conservation and welfare of mantled howler monkeys at Los Tuxtlas.


Assuntos
Alouatta , Glucocorticoides , Masculino , Animais , Glucocorticoides/metabolismo , Comportamento Animal/fisiologia , Alouatta/fisiologia , Primatas , México
9.
Chaos ; 34(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38885072

RESUMO

The equatorial region of the Earth's atmosphere serves as both a significant locus for phenomena, including the Madden-Julian Oscillation (MJO), and a source of formidable complexity. This complexity arises from the intricate interplay between nonlinearity and thermodynamic processes, particularly those involving moisture. In this study, we employ a normal mode decomposition of atmospheric reanalysis ERA-5 datasets to investigate the influence of nonlinearity and moisture on amplitude growth, propagation speed, and mode coupling associated with equatorially trapped waves. We focus our analysis on global-scale baroclinic Kelvin and Rossby waves, recognized as crucial components contributing to the variability of the MJO. We examine the dependence of wave amplitudes on the background moisture field in the equatorial region, as measured by total column water vapor. Our analysis demonstrates the crucial role of moisture in exciting these waves. We further investigate the dependence of the propagation speed of the waves on their amplitudes and the background moisture field. Our analysis reveals a robust correlation between the phase speed of the normal modes and their corresponding amplitude, whereas a weaker correlation is found between the eigenmodes' phase speed and the moisture field. Hence, our findings suggest that moisture plays a role in exciting the global-scale Rossby-Kelvin structure of the MJO. In this context, the propagation speed of the eigenmodes is mainly influenced by their amplitudes, underscoring the significant role of nonlinearity in wave propagation.

10.
Environ Sci Technol ; 57(24): 8902-8910, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37290054

RESUMO

Antibiotic resistance (AR) determinants are enriched in animal manures, a significant portion of which is land-applied as a soil amendment or as fertilizer, leading to potential AR runoff and microbial pollution in adjacent surface waters. To effectively inform AR monitoring and mitigation efforts, a thorough understanding and description of the persistence and transport of manure-derived AR in flowing waters are needed. We used experimental recirculating mesocosms to assess water-column removal rates of antibiotic resistance genes (ARGs) originating from a cow manure slurry collected from a dairy farm. We quantified the effect of three benthic (i.e., bottom) substrate variations and particle sizes of manure slurry on water column removal rates. Overall, we observed variation in ARG behavior across substrate treatments and particle sizes. For ARGs associated with small particles, removal rates were higher in mesocosms with a substrate. tetW was typically removed at the highest rates across particle size and treatment, followed by ermB and blaTEM. Our data suggests that both substrate character and particle size exert control on the fate and transport of ARGs in surface waters, laying the foundation for future research in this area to establish a predictive framework for AR persistence and fate in flowing waters.


Assuntos
Antibacterianos , Esterco , Animais , Bovinos , Feminino , Antibacterianos/farmacologia , Tamanho da Partícula , Genes Bacterianos , Rios , Microbiologia do Solo , Resistência Microbiana a Medicamentos/genética , Solo
11.
Environ Sci Technol ; 57(35): 13161-13171, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37610829

RESUMO

Environmental DNA (eDNA) in aquatic systems is a complex mixture that includes dissolved DNA, intracellular DNA, and particle-adsorbed DNA. Information about the various components of eDNA and their relative proportions could be used to discern target organism abundance and location. However, a limited knowledge of eDNA adsorption dynamics and interactions with other materials hinders these applications. To address this gap, we used recirculating stream mesocosms to investigate the impact of suspended materials (fine particulate organic matter, plankton, clay, and titanium dioxide) on the eDNA concentration and particle size distribution (PSD) from two fish species in flowing water. Our findings revealed that eDNA rapidly adsorbs to other materials in the water column, affecting its concentration and PSD. Nonetheless, only particulate organic matter affected eDNA removal rate after 30 h. Moreover, we observed that the removal of larger eDNA components (≥10 µm) was more strongly influenced by physical processes, whereas the removal of smaller eDNA components was driven by biological degradation. This disparity in removal mechanisms between larger and smaller eDNA components could explain changes in eDNA composition over time and space, which have implications for modeling the spatial distribution and abundance of target species and optimizing eDNA detection in high turbidity systems.


Assuntos
DNA Ambiental , Animais , Tamanho da Partícula , Fenômenos Físicos , Adsorção , Material Particulado , Água
12.
Nano Lett ; 22(7): 2611-2617, 2022 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-35362986

RESUMO

Protein detection is a universal tool critical to many applications in medicine, agriculture, and biotechnology. We developed a novel protein detection method combining light transmission spectroscopy and particle-size analysis of gold nanospheres monovalently functionalized with polyclonal antibodies and applied it to an emerging challenge for such technologies─the monitoring of environmental proteins (eProteins) present in natural aquatic systems. These are an underreported source of pollution and include the pseudopersistent Cry toxins that enter aquatic ecosystems from surrounding genetically engineered crops. The assay is capable of detecting proteins in complex matrices, such as water samples collected in the field, making it a competitive assay for eProtein detection. It is sensitive, reaching 1.25 ng mL-1, and we demonstrate its application to the detection of Cry1Ab from subsurface tile-drain and streamwater samples from agricultural waterways. The assay can also be quickly adapted for other protein detection applications in the future.


Assuntos
Ouro , Nanopartículas Metálicas , Proteínas de Bactérias/genética , Ecossistema , Ouro/química , Proteínas Hemolisinas/análise , Nanopartículas Metálicas/química , Plantas Geneticamente Modificadas/química , Plantas Geneticamente Modificadas/metabolismo , Análise Espectral
13.
Univers Access Inf Soc ; 22(2): 525-536, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35069063

RESUMO

Remote monitoring of biometric data in the elderly population is an important asset for improving the quality of life and level of independence of elderly people living alone. However, the design and implementation of health technological solutions often disregard the elderly physiological and psychological abilities, leading to low adoption of these technologies. We evaluate the usability of a remote patient monitoring solution, VITASENIOR-MT, which is based on the interaction with a television set. Twenty senior participants (over 64 years) and a control group of 20 participants underwent systematic tests with the health platform and assessed its usability through several questionnaires. Elderly participants scored high on the usability of the platform, very close to the evaluation of the control group. Sensory, motor and cognitive limitations were the issues that most contributed to the difference in usability assessment between the elderly group and the control group. The solution showed high usability and acceptance regardless of age, digital literacy, education and impairments (sensory, motor and cognitive), which shows its effective viability for use and implementation as a consumer product in the senior market.

14.
BMC Psychiatry ; 22(1): 713, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36384505

RESUMO

BACKGROUND: Mental Health Literacy (MHL) has become a focus of research in recent decades, as a prerequisite for early identification and intervention for mental health problems. Although several instruments have been developed for assessing MHL, there is a need for brief and psychometrically sound measures to capture important aspects of MHL in large and diverse adult samples. The present study aimed to: (1) provide a revised and shorter version of a previously validated questionnaire for assessing MHL; and (2) examine the psychometric properties of the MHLq-SVa in student samples from six different countries (China, India, Indonesia, Portugal, Thailand, and United States). METHODS: The study involved 2180 senior school and undergraduate students, aged between 17 and 25 years old, from China, India, Indonesia, Portugal, Thailand, and the United States. Participants responded to the Mental Health Literacy Questionnaire for young adults (MHLq-ya), in their native language, following its translation and adaptation for each culture. The MHLq-ya comprises 29 items, organized into four dimensions: Knowledge of mental health problems; Erroneous beliefs/stereotypes; First-aid skills and help-seeking behavior; Self-help strategies. Confirmatory factor analyses and internal consistency analyses were performed on the combined data. RESULTS: Data from the different countries supported a shorter version of the questionnaire (MHLq-SVa), composed of 16 items that fit with previously defined dimensions. Internal consistency and between-factor correlations further supported the adequacy of the instrument's psychometric properties. CONCLUSION: The study provided preliminary support for the construct validity and reliability of the MHLq-SVa as a measure for assessing MHL in young adults from six different countries and languages. Future studies are needed to further validate the measure and undertake multicultural comparisons of MHL in diverse samples from around the globe.


Assuntos
Letramento em Saúde , Adulto Jovem , Humanos , Estados Unidos , Adolescente , Adulto , Letramento em Saúde/métodos , Saúde Mental , Reprodutibilidade dos Testes , Indonésia , Portugal , Tailândia , Inquéritos e Questionários , China
15.
Ann Vasc Surg ; 79: 153-161, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34644633

RESUMO

OBJECTIVES: Vascular surgery patients commonly have several comorbidities that cumulatively lead to a frailty status. The cumulative comorbidities disproportionately increase the risk of adverse events and are also associated with worsened long-term prognosis. In recent years, several tools have been elaborated with the objective of quantifying a patient's frailty. One of them is the modified frailty index-5 (mFI-5), a simplified and easy to use index. There is scarce data regarding its value as a prognostic factor in aortoiliac occlusive disease. The aim of this work is to validate mFI-5 as a potential postoperative prognostic indicator in this population. METHODS: From January 2013 to January 2020, 109 patients who underwent elective revascularizations, either endovascular or open surgery, having Trans-Atlantic Inter-Society Consensus II type D aortoiliac lesions in a tertiary and a regional hospital were selected from a prospective vascular registry. Demographic data was collected including diabetes mellitus, chronic heart failure, chronic obstructive pulmonary disease, arterial hypertension requiring medication and functional status. The 30-d and subsequent long-term surveillance outcomes were also collected including major adverse cardiovascular events (MACE), major adverse limb events (MALE) and all-cause mortality were assessed in the 30-d post-procedure and in the subsequent long-term surveillance period. The mFI-5 was applied to this population to evaluate the prognostic impact of this frailty marker on mortality and morbidity. RESULTS: In the long-term follow-up, mFI-5 was significantly associated with MACE (hazard ratio [HR] 2.469; 95% confidence interval [CI]: 1.267-4.811; P = .008) and all-cause mortality (HR 2.585; 95% CI: 1.270-5.260; P = .009). However, there was no significant association with 30-day outcomes. Along with the presence of chronic kidney disease, mFI-5 was the prognostic factor better able of predicting MACE. No prognostic value was found regarding short-term outcomes. CONCLUSION: The mFI-5 index may have a role in predicting long term outcomes, namely MACE and all-cause mortality, in the subset of patients with extensive aortoiliac occlusive disease. Its ease of use can foster its application in risk stratification and contribute for the decision-making process.


Assuntos
Doenças da Aorta/cirurgia , Arteriopatias Oclusivas/cirurgia , Procedimentos Endovasculares , Idoso Fragilizado , Fragilidade/complicações , Artéria Ilíaca/cirurgia , Procedimentos Cirúrgicos Vasculares , Fatores Etários , Idoso , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/mortalidade , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/mortalidade , Comorbidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Fragilidade/diagnóstico , Fragilidade/mortalidade , Nível de Saúde , Humanos , Artéria Ilíaca/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/mortalidade
16.
Am J Primatol ; 84(11): e23437, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36128630

RESUMO

Most primate taxa are threatened by extinction and their populations are decreasing. The persistence of primates is thus conditional on conservation actions aimed at protecting them and their habitat. Here, we focus on the conservation of mantled howler monkeys (Alouatta palliata) in the Los Tuxtlas Biosphere Reserve, Mexico. Following the creation of the reserve in 1998, habitat availability and howler monkey abundance increased, suggesting that progress was being made in terms of the conservation of this species. Recent events, however, suggest otherwise, as mantled howler monkey habitat within the biosphere reserve is being disturbed by mining operations endorsed by the Mexican government. We report this case to raise awareness about the challenges for primate and habitat conservation in protected areas.


Assuntos
Alouatta , Fragilidade , Animais , Ecossistema , México
17.
Am J Primatol ; 84(6): e23377, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35417046

RESUMO

Anthropogenic noise is increasingly disturbing natural soundscapes and affecting the physiology, behavior, and fitness of wildlife. However, our knowledge about the impact of anthropogenic noise on wild primates is scant. Here, we assess the effects of anthropogenic noise on the behavior of male mantled howler monkeys (Alouatta palliata). Specifically, we describe the types, rates, and sound pressure level (SPL) of anthropogenic noise that occurs in areas inhabited by mantled howler monkeys and determine if the behavioral responses of males to anthropogenic noise are influenced by noise attributes. For 1 year (1753 h), we characterized anthropogenic noise in the Los Tuxtlas Biosphere Reserve (Veracruz, Mexico) and studied the behavior of males belonging to five groups. Anthropogenic noise was common, diverse, and varied among areas in terms of rate, type, and SPL. Males did not display behavioral responses toward most (60%) anthropogenic noises, but were more likely to respond to certain noise types (e.g., aerial traffic) and toward noise with high SPL. Group identity influenced the likelihood of displaying behavioral responses to noise. The most common behavioral responses were vocalizations and vigilance. Males vocalized in response to noise with high SPL, although this relationship depended on group identity. The effect of the number of noises on vocalizations also varied among groups. Males were more likely to display vigilance toward high SPL and infrequent noise, but, again, these relationships varied among groups. In sum, anthropogenic noise is pervasive in areas inhabited by mantled howler monkeys and influences male behavior. Experience and frequency of exposure may modulate the behavioral responses of male mantled howler monkeys to noise and explain the group differences.


Assuntos
Alouatta , Alouatta/fisiologia , Animais , Comportamento Animal/fisiologia , Atividades Humanas , Masculino , México , Ruído
18.
Environ Sci Technol ; 55(8): 4688-4697, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33755442

RESUMO

Environmental proteins (eProteins), such as Cry proteins associated with genetically engineered (GE) organisms, are present in ecosystems worldwide, but only rarely reach concentrations with detectable ecosystem-level impacts. Despite their ubiquity, the degradation and fate of Cry and other eProteins are mostly unknown. Here, we report the results of an experiment where we added Cry proteins leached from GE Bt maize to a suite of 19 recirculating experimental streams. We found that Cry exhibited a biphasic degradation with an initial phase of rapid and variable degradation within 1 h, followed by a slow and steady phase of degradation with traces of protein persisting after 48 h. The initial degradation was correlated with heterotrophic respiration and water column dissolved oxygen, confirming a previously documented association with stream metabolism. However, protein degradation persisted even with no biofilm and was faster at a more acidic pH, suggesting that water chemistry is also a critical factor in both degradation and subsequent detection. We suggest that Cry, as well as other eProteins, will have a rapid degradation caused by denaturation of proteins and pH changes, which confirms that the detection of Cry proteins in natural streams must be the result of steady and consistent leaching into the environment.


Assuntos
Toxinas de Bacillus thuringiensis , Plantas Geneticamente Modificadas , Rios , Proteínas de Bactérias/genética , Ecossistema , Endotoxinas , Concentração de Íons de Hidrogênio , Água/química , Zea mays
19.
Am J Phys Anthropol ; 174(3): 396-406, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33429455

RESUMO

OBJECTIVE: Reproduction entails several challenges to primate females, among which energetic costs are remarkable at certain stages of the reproductive cycle. Still, females may use behavioral and physiological strategies to cope with those challenges. We had previously reported covariation between female energetic condition through the reproductive cycle and time-budget adjustments in mantled howler monkeys (Alouatta palliata). Accordingly, we suggested that behavioral flexibility allowed coping with the energetic challenges of reproduction. Subsequent evidence from the same population, however, suggested otherwise, so we performed a follow-up study on the variation in female reproductive energetics based on a larger sample of females. METHODS: We studied 48 free-ranging adult females at Los Tuxtlas (Mexico). We assessed energy balance via urinary C-peptide concentrations (2717 urine samples), behavioral energy intake and expenditure (5728 sampling hours), and physiological energy expenditure via fecal triiodothyronine metabolites (fTH3; 3138 fecal samples). RESULTS: We found that energy balance varied among reproductive states: (a) cycling was a period of low C-peptide concentrations; (b) the highest C-peptide concentrations occurred during gestation; and (c) the beginning of lactation marked a notable decrease in C-peptide concentrations, which then improved at mid-lactation to again decline at lactation offset. These peaks and valleys in energy balance did not seem to be associated with variation in energy acquisition but were rather mirrored by activity levels and fTH3 during lactation. DISCUSSION: Energy balance was not preserved through the reproductive cycle, supporting previous contentions that the reproductive performance of female mantled howler monkeys may be energetically constrained. The contrast between these and results that we have previously reported, highlights the importance of conducting follow-up studies to continually improve our understanding of the reproductive energetics of primate females.


Assuntos
Alouatta/fisiologia , Metabolismo Energético/fisiologia , Reprodução/fisiologia , Animais , Antropologia Física , Peptídeo C/urina , Ingestão de Energia/fisiologia , Fezes/química , Comportamento Alimentar/fisiologia , Feminino , Seguimentos , Lactação/fisiologia , México , Hormônios Tireóideos/análise
20.
Am J Primatol ; 83(5): e23252, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33666267

RESUMO

Loud calls (i.e., long-range acoustic signals) regulate resource competition among neighboring groups of conspecifics in several nonhuman primate species. Ultimate explanations for primate loud calls include mate, offspring, and food defense. Additionally, loud calls may provide valuable information pertaining to the identity and health status of callers, their competitive abilities, and their spatial location. The loud calls of howler monkeys (Alouatta) have been thoroughly studied and seem to play an important function in the defense of valuable resources in a variety of socioecological contexts. Here, we examined whether the behavioral responses of mantled howler monkeys (Alouatta palliata) to natural loud calls from neighbors are linked to three factors: food availability, familiarity, and distance between groups. We studied three groups of mantled howler monkeys at La Flor de Catemaco (Los Tuxtlas, Mexico) for 15 months (1817 observation hours), during which we recorded 236 neighbor loud calls. Food availability per se did not influence the behavior of groups receiving loud calls, although males produced longer vocal responses toward unfamiliar neighbors when food availability decreased. Groups vocalized quicker and both vocalized and moved for longer after loud calls from unfamiliar neighbors. Additionally, groups vocalized and moved for longer at shorter distances from unfamiliar neighbors compared with familiar neighbors. Finally, groups usually moved away from calling neighbors that were closer. These results indicate that the behavioral responses of mantled howler monkeys to loud calls from neighbor groups are associated with the integration of information pertaining to caller identity as well as to their ecological and spatial context.


Assuntos
Alouatta , Acústica , Animais , Masculino , Movimento , Reprodução
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