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1.
Am J Primatol ; 85(2): e23464, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36642976

RESUMO

The Tropical Andes Biodiversity Hotspot holds a remarkable number of species at risk of extinction due to anthropogenic habitat loss, hunting, and climate change. One of these species, the critically endangered yellow-tailed woolly monkey (Lagothrix flavicauda), was recently observed in the region Junín, 206 km south of its previously known distribution. This range extension, combined with continued habitat loss, calls for a reevaluation of the species distribution, and available suitable habitat. Here, we present novel data from surveys at 53 sites in the regions of Junín, Cerro de Pasco, Ayacucho, and Cusco. We encountered L. flavicauda at 9 sites, all in Junín, and the congeneric Lagothrix lagotricha tschudii at 20 sites, but never in sympatry. Using these new localities along with all previous geographic localities for the species, we made predictive species distribution models based on ecological niche modeling using a generalized linear model and maximum entropy. Each model incorporated bioclimatic variables, forest cover, vegetation measurements, and elevation as predictor variables. The model evaluation showed >80% accuracy for all measures. Precipitation was the strongest predictor of species presence. Habitat suitability maps illustrate potential corridors for gene flow between the southern and northern populations, although much of this area is inhabited by L. l. tschudii whereas L. flavicauda has yet to be officially confirmed in these areas, by these or any other scientific surveys. An analysis of the current protected area (PA) network showed that ~75% of remaining suitable habitat is unprotected. With this, we suggest priority areas for new PAs or expansions to existing reserves that would conserve potential corridors between L. flavicauda populations. Further surveys and characterization of the distribution in intermediate areas, combined with studies on gene flow through these areas, are still needed to protect this species.


Assuntos
Atelinae , Ecossistema , Animais , Peru , Atelinae/genética , Florestas
2.
Proc Biol Sci ; 289(1982): 20221254, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36100027

RESUMO

In the last 300 thousand years, the genus Chlorocebus expanded from equatorial Africa into the southernmost latitudes of the continent, where colder climate was a probable driver of natural selection. We investigated population-level genetic variation in the mitochondrial uncoupling protein 1 (UCP1) gene region-implicated in non-shivering thermogenesis (NST)-in 73 wild savannah monkeys from three taxa representing this southern expansion (Chlorocebus pygerythrus hilgerti, Chlorocebus cynosuros and Chlorocebus pygerythrus pygerythrus) ranging from Kenya to South Africa. We found 17 single nucleotide polymorphisms with extended haplotype homozygosity consistent with positive selective sweeps, 10 of which show no significant linkage disequilibrium with each other. Phylogenetic generalized least-squares modelling with ecological covariates suggest that most derived allele frequencies are significantly associated with solar irradiance and winter precipitation, rather than overall low temperatures. This selection and association with irradiance is demonstrated by a relatively isolated population in the southern coastal belt of South Africa. We suggest that sunbathing behaviours common to savannah monkeys, in combination with the strength of solar irradiance, may mediate adaptations to thermal stress via NST among savannah monkeys. The variants we discovered all lie in non-coding regions, some with previously documented regulatory functions, calling for further validation and research.


Assuntos
Aclimatação , Termogênese , Animais , Chlorocebus aethiops , Filogenia , África do Sul , Proteína Desacopladora 1
3.
Naturwissenschaften ; 107(5): 40, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870408

RESUMO

Paleontology has long relied on assumptions about the genetic and developmental influences on skeletal variation. The last few decades of developmental genetics have elucidated the genetic pathways involved in making teeth and patterning the dentition. Quantitative genetic analyses have refined this genotype:phenotype map even more, especially for primates. We now have the ability to define dental traits with a fair degree of fidelity to the underlying genetic architecture; for example, the molar module component (MMC) and the premolar-molar module (PMM) that have been defined through quantitative genetic analyses. We leverage an extensive dataset of extant and extinct hominoid dental variation to explore how these two genetically patterned phenotypes have evolved through time. We assess MMC and PMM to test the hypothesis that these two traits reveal a more biologically informed taxonomy at the genus and species levels than do more traditional measurements. Our results indicate that MMC values for hominids fall into two categories and that Homo is derived compared with earlier taxa. We find a more variable, species-level pattern for PMM. These results, in combination with previous research, demonstrate that MMC reflects the phenotypic output of a more evolutionarily stable, or phylogenetically congruent, genetic mechanism, and PMM is a reflection of a more evolutionarily labile mechanism. These results suggest that the human lineage since the split with chimpanzees may not represent as much genus-level variation as has been inferred from traits whose etiologies are not understood.


Assuntos
Dentição , Fósseis/anatomia & histologia , Hominidae/classificação , Hominidae/genética , Filogenia , Animais , Genótipo , Humanos , Fenótipo
4.
Am J Phys Anthropol ; 171(1): 89-99, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31675103

RESUMO

OBJECTIVES: To compare longitudinal weight gain in captive and wild juvenile vervet monkeys and conduct an empirical assessment of different mechanistic growth models. METHODS: Weights were collected from two groups of captive monkeys and two consecutive cohorts of wild monkeys until the end of the juvenile period (~800 days). The captive groups were each fed different diets, while the wild groups experienced different ecological conditions. Three different growth curve models were compared. RESULTS: By 800 days, the wild juveniles were lighter, with a slower maximum growth rate, and reached asymptote earlier than their captive counterparts. There were overall differences in weight and growth rate across the two wild cohorts. This corresponded to differences in resource availability. There was considerable overlap in growth rate and predicted adult weight of male and females in the first, but not the second, wild cohort. Maternal parity was not influential. While the von Bertalanffy curve provided the best fit to the data sets modeled together, the Logistic curve best described growth in the wild cohorts when considered separately. CONCLUSIONS: The growth curves of the two captive cohorts are likely to lie near the maximum attainable by juvenile vervets. It may be helpful to include deviations from these rates when assessing the performance of wild vervet monkeys. The comparison of wild and captive juveniles confirmed the value of comparing different growth curve models, and an appreciation that the best models may well differ for different populations. Choice of mechanistic growth model can, therefore, be empirically justified, rather than theoretically predetermined.


Assuntos
Animais Selvagens/crescimento & desenvolvimento , Animais de Zoológico/crescimento & desenvolvimento , Chlorocebus aethiops/crescimento & desenvolvimento , Dieta/veterinária , Animais , Feminino , Masculino , Modelos Biológicos
5.
Proc Natl Acad Sci U S A ; 113(33): 9262-7, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27402751

RESUMO

Developmental genetics research on mice provides a relatively sound understanding of the genes necessary and sufficient to make mammalian teeth. However, mouse dentitions are highly derived compared with human dentitions, complicating the application of these insights to human biology. We used quantitative genetic analyses of data from living nonhuman primates and extensive osteological and paleontological collections to refine our assessment of dental phenotypes so that they better represent how the underlying genetic mechanisms actually influence anatomical variation. We identify ratios that better characterize the output of two dental genetic patterning mechanisms for primate dentitions. These two newly defined phenotypes are heritable with no measurable pleiotropic effects. When we consider how these two phenotypes vary across neontological and paleontological datasets, we find that the major Middle Miocene taxonomic shift in primate diversity is characterized by a shift in these two genetic outputs. Our results build on the mouse model by combining quantitative genetics and paleontology, and thereby elucidate how genetic mechanisms likely underlie major events in primate evolution.


Assuntos
Evolução Biológica , Genética , Paleontologia , Papio hamadryas/genética , Dente/anatomia & histologia , Animais , Feminino , Masculino , Camundongos , Papio hamadryas/anatomia & histologia , Papio hamadryas/classificação , Fenótipo , Filogenia
6.
Genome Res ; 25(12): 1921-33, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26377836

RESUMO

We describe a genome reference of the African green monkey or vervet (Chlorocebus aethiops). This member of the Old World monkey (OWM) superfamily is uniquely valuable for genetic investigations of simian immunodeficiency virus (SIV), for which it is the most abundant natural host species, and of a wide range of health-related phenotypes assessed in Caribbean vervets (C. a. sabaeus), whose numbers have expanded dramatically since Europeans introduced small numbers of their ancestors from West Africa during the colonial era. We use the reference to characterize the genomic relationship between vervets and other primates, the intra-generic phylogeny of vervet subspecies, and genome-wide structural variations of a pedigreed C. a. sabaeus population. Through comparative analyses with human and rhesus macaque, we characterize at high resolution the unique chromosomal fission events that differentiate the vervets and their close relatives from most other catarrhine primates, in whom karyotype is highly conserved. We also provide a summary of transposable elements and contrast these with the rhesus macaque and human. Analysis of sequenced genomes representing each of the main vervet subspecies supports previously hypothesized relationships between these populations, which range across most of sub-Saharan Africa, while uncovering high levels of genetic diversity within each. Sequence-based analyses of major histocompatibility complex (MHC) polymorphisms reveal extremely low diversity in Caribbean C. a. sabaeus vervets, compared to vervets from putatively ancestral West African regions. In the C. a. sabaeus research population, we discover the first structural variations that are, in some cases, predicted to have a deleterious effect; future studies will determine the phenotypic impact of these variations.


Assuntos
Chlorocebus aethiops/genética , Genoma , Genômica , Animais , Chlorocebus aethiops/classificação , Coloração Cromossômica , Biologia Computacional/métodos , Evolução Molecular , Rearranjo Gênico , Variação Genética , Genômica/métodos , Cariótipo , Complexo Principal de Histocompatibilidade/genética , Anotação de Sequência Molecular , Filogenia , Filogeografia
7.
Biomacromolecules ; 19(1): 71-84, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29227674

RESUMO

Drug delivery to bone is challenging, whereby drug distribution is commonly <1% of injected dose, despite development of several bone-targeted drug delivery systems specific to hydroxyapatite. These bone-targeted drug delivery systems still suffer from poor target cell localization within bone, as at any given time overall bone volume is far greater than acutely remodeling bone volume, which harbors relevant cell targets (osteoclasts or osteoblasts). Thus, there exists a need to target bone-acting drugs specifically to sites of bone remodeling. To address this need, this study synthesized oligo(ethylene glycol) copolymers based on a peptide with high affinity to tartrate-resistant acid phosphatase (TRAP), an enzyme deposited by osteoclasts during the bone resorption phase of bone remodeling, which provides greater specificity relevant for bone cell drugging. Gradient and random peptide orientations, as well as polymer molecular weights, were investigated. TRAP-targeted, high molecular weight (Mn) random copolymers exhibited superior accumulation in remodeling bone, where fracture accumulation was observed for at least 1 week and accounted for 14% of tissue distribution. Intermediate and low Mn random copolymer accumulation was lower, indicating residence time depends on Mn. High Mn gradient polymers were cleared, with only 2% persisting at fractures after 1 week, suggesting TRAP binding depends on peptide density. Peptide density and Mn are easily modified in this versatile targeting platform, which can be applied to a range of bone drug delivery applications.


Assuntos
Sistemas de Liberação de Medicamentos , Peptídeos/metabolismo , Polímeros/farmacocinética , Acrilamida/química , Animais , Remodelação Óssea , Células Cultivadas , Feminino , Corantes Fluorescentes/química , Humanos , Masculino , Camundongos Endogâmicos C57BL , Peso Molecular , Osteoclastos/enzimologia , Peptídeos/química , Polímeros/química , Fosfatase Ácida Resistente a Tartarato/metabolismo , Distribuição Tecidual
8.
Am J Phys Anthropol ; 166(3): 682-707, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29577231

RESUMO

OBJECTIVES: Direct comparative work in morphology and growth on widely dispersed wild primate taxa is rarely accomplished, yet critical to understanding ecogeographic variation, plastic local variation in response to human impacts, and variation in patterns of growth and sexual dimorphism. We investigated population variation in morphology and growth in response to geographic variables (i.e., latitude, altitude), climatic variables (i.e., temperature and rainfall), and human impacts in the vervet monkey (Chlorocebus spp.). METHODS: We trapped over 1,600 wild vervets from across Sub-Saharan Africa and the Caribbean, and compared measurements of body mass, body length, and relative thigh, leg, and foot length in four well-represented geographic samples: Ethiopia, Kenya, South Africa, and St. Kitts & Nevis. RESULTS: We found significant variation in body mass and length consistent with Bergmann's Rule in adult females, and in adult males when excluding the St. Kitts & Nevis population, which was more sexually dimorphic. Contrary to Rensch's Rule, although the South African population had the largest average body size, it was the least dimorphic. There was significant, although very small, variation in all limb segments in support for Allen's Rule. Females in high human impact areas were heavier than those with moderate exposures, while those in low human impact areas were lighter; human impacts had no effect on males. CONCLUSIONS: Vervet monkeys appear to have adapted to local climate as predicted by Bergmann's and, less consistently, Allen's Rule, while also responding in predicted ways to human impacts. To better understand deviations from predicted patterns will require further comparative work in vervets.


Assuntos
Tamanho Corporal/fisiologia , Chlorocebus aethiops/anatomia & histologia , Chlorocebus aethiops/fisiologia , África Subsaariana , Animais , Antropologia Física , Extremidades/anatomia & histologia , Extremidades/fisiologia , Feminino , Masculino , Caracteres Sexuais
9.
Bull Environ Contam Toxicol ; 101(2): 294, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29971608

RESUMO

The original version of this article contained a mistake. Author name in the text citation and reference in section should be Maldonado et al (2016), it was incorrectly spelled as Maldinado et al (2015).

10.
Bull Environ Contam Toxicol ; 100(6): 741-747, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29796875

RESUMO

Northern Cardinal eggs from six neighborhoods near Washington DC were analyzed for organochlorine pesticides and PCBs. All compounds were detected more frequently and at higher concentrations in more heavily urbanized neighborhoods. DDT (mostly as p,p'-DDE) was detected in all neighborhoods. p,p'-DDT was typically 0.5‒16 ng/g (ww) in most suburban neighborhoods but was not detected (< 0.1 ng/g) in more rural areas; however, p,p'-DDT was 127‒1130 ng/g in eggs from two suburban Maryland nests and comprised 65.7% of total p,p'-DDT isomers in the most contaminated sample, indicating recent exposure to un-weathered DDT. Total chlordane (sum of 5 compounds) was 2‒70 ng/g; concentrations were greatest in older suburban neighborhoods. Total PCB (sum of detected congeners) was < 5‒21 ng/g. Congener patterns were similar in all neighborhoods and resembled those typical of weathered mixtures. Results indicate that wildlife remains exposed to low concentrations of legacy contaminants in suburban neighborhoods and that cardinal eggs can be used to monitor localized contamination.


Assuntos
Ovos/análise , Poluentes Ambientais/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Animais , Aves , DDT/análise , Diclorodifenil Dicloroetileno/análise , District of Columbia , Monitoramento Ambiental/métodos , Hidrocarbonetos Clorados/análise
11.
BMC Anesthesiol ; 17(1): 72, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28558697

RESUMO

BACKGROUND: Lack of familiarity with the content of current guidelines is a major factor associated with non-compliance by clinicians. It is conceivable that cognitive aids with regularly updated medical content can guide clinicians' task performance by evidence-based practices, even if they are unfamiliar with the actual guideline. Acute hyponatraemia as a consequence of TURP syndrome is a rare intraoperative event, and current practice guidelines have changed from slow correction to rapid correction of serum sodium levels. The primary objective of this study was to compare the management of a simulated severe gynaecological transurethral resection of the prostate (TURP) syndrome under spinal anaesthesia with either: an electronic cognitive aid, or with management from memory alone. The secondary objective was to assess the clinical relevance and participant perception of the usefulness of the cognitive aid. METHODS: Anaesthetic teams were allocated to control (no cognitive aid; n = 10) or intervention (cognitive aid provided; n = 10) groups. We identified eight evidence-based management tasks for severe TURP syndrome from current guidelines and subdivided them into acute heart failure (AHF)/pulmonary oedema tasks (5) and acute hyponatraemia tasks (3). Implementation of the treatment steps was measured by scoring task items in a binary fashion (yes/no). To assess whether or not the cognitive aid had prompted a treatment step, participants from the cognitive aid group were questioned during debriefing on every single treatment step. At the end of the simulation, session participants were asked to complete a survey. RESULTS: Teams in the cognitive aid group considered evidence-based treatment steps significantly more often than teams of the control group (96% vs. 50% for 'AHF/pulmonary oedema' p < 0.001; 79% vs. 12% for 'acute hyponatraemia' p < 0.001). Without the cognitive aid, performance would have been comparable across both groups. Nurses, trainees, and consultants derived equal benefit from the cognitive aid. CONCLUSIONS: The cognitive aid improved the implementation of evidence-based practices in a simulated intraoperative scenario. Cognitive aids with current medical content could help to close the translational gap between guideline publication and implementation in acute patient care. It is important that the cognitive aid should be familiar, in a format that has been used in practice and training.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Técnicas de Apoio para a Decisão , Emergências , Hiponatremia/terapia , Raquianestesia , Cesárea , Humanos , Complicações Intraoperatórias , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Treinamento por Simulação , Método Simples-Cego
12.
BMC Anesthesiol ; 17(1): 46, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28320312

RESUMO

BACKGROUND: Cognitive aids have come to be viewed as promising tools in the management of perioperative critical events. The majority of published simulation studies have focussed on perioperative crises that are characterised by time pressure, rare occurrence, or complex management steps (e.g., cardiac arrest emergencies, management of the difficult airway). At present, there is limited information on the usefulness of cognitive aids in critical situations with moderate time pressure and complexity. Intraoperative myocardial infarction may be an emergency to which these limitations apply. METHODS: Anaesthetic teams were allocated to control (no cognitive aid; n = 10) or intervention (cognitive aid provided; n = 10) groups. The primary aim of this study was to compare cognitive aid versus memory for intraoperative ST-elevation myocardial infarction (STEMI) management in a simulation of caesarean delivery under spinal anaesthesia. We identified nine evidence-based metrics of essential care from current guidelines and subdivided them into mandatory (high level of evidence; no interference with surgery) and optional (lower class of recommendation; possible impact on surgery) tasks. Six clinically relevant tasks were added by consensus. Implementation of these steps was measured by scoring task items in a binary fashion (yes/no). The interval between the diagnosis of STEMI and the first contact with the cardiac catheterisation lab was measured. To determine whether or not the cognitive aid had prompted an action, participants from the cognitive aid group were interviewed during debriefing on every single treatment step. At the end of the simulation, session participants were asked to complete a survey. RESULTS: The presence of the cognitive aid did not shorten the time interval until the cardiac catheterisation lab was contacted. The availability of the cognitive aid improved task performance in the tasks identified from the guidelines (93% vs. 69%; p < 0.001) as well as overall task performance (87.5% vs. 59%; p < 0.001). The observed difference in performance can be attributed to the use of the cognitive aid, as performance from memory alone would have been comparable across both groups. Trainees appeared to derive greater benefit from the cognitive aid than did consultants and nurses. CONCLUSIONS: The management of intraoperative ST-elevation myocardial infarction can be improved if teams use a cognitive aid. Trainees appeared to derive greater benefit from the cognitive aid than did consultants and nurses.


Assuntos
Cesárea/efeitos adversos , Técnicas de Apoio para a Decisão , Gerenciamento Clínico , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Treinamento por Simulação/métodos , Feminino , Humanos , Complicações Intraoperatórias/terapia , Gravidez , Complicações Cardiovasculares na Gravidez/terapia , Estudos Prospectivos , Distribuição Aleatória , Método Simples-Cego , Análise e Desempenho de Tarefas
13.
Appl Environ Microbiol ; 82(19): 5910-7, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27474712

RESUMO

UNLABELLED: Staphylococcus aureus is an important pathogen of humans and animals. We genome sequenced 90 S. aureus isolates from The Gambia: 46 isolates from invasive disease in humans, 13 human carriage isolates, and 31 monkey carriage isolates. We inferred multiple anthroponotic transmissions of S. aureus from humans to green monkeys (Chlorocebus sabaeus) in The Gambia over different time scales. We report a novel monkey-associated clade of S. aureus that emerged from a human-to-monkey switch estimated to have occurred 2,700 years ago. Adaptation of this lineage to the monkey host is accompanied by the loss of phage-carrying genes that are known to play an important role in human colonization. We also report recent anthroponotic transmission of the well-characterized human lineages sequence type 6 (ST6) and ST15 to monkeys, probably because of steadily increasing encroachment of humans into the monkeys' habitat. Although we have found no evidence of transmission of S. aureus from monkeys to humans, as the two species come into ever-closer contact, there might be an increased risk of additional interspecies exchanges of potential pathogens. IMPORTANCE: The population structures of Staphylococcus aureus in humans and monkeys in sub-Saharan Africa have been previously described using multilocus sequence typing (MLST). However, these data lack the power to accurately infer details regarding the origin and maintenance of new adaptive lineages. Here, we describe the use of whole-genome sequencing to detect transmission of S. aureus between humans and nonhuman primates and to document the genetic changes accompanying host adaptation. We note that human-to-monkey switches tend to be more common than the reverse and that a novel monkey-associated clade is likely to have emerged from such a switch approximately 2,700 years ago. Moreover, analysis of the accessory genome provides important clues as to the genetic changes underpinning host adaptation and, in particular, shows that human-to-monkey switches tend to be associated with the loss of genes known to confer adaptation to the human host.


Assuntos
Chlorocebus aethiops , Genoma Bacteriano , Doenças dos Macacos/transmissão , Infecções Estafilocócicas/transmissão , Staphylococcus aureus/fisiologia , Animais , Portador Sadio , Gâmbia , Humanos , Doenças dos Macacos/microbiologia , Filogenia , Análise de Sequência de DNA , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/classificação , Staphylococcus aureus/genética
15.
Am J Phys Anthropol ; 159(1): 17-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26265297

RESUMO

OBJECTIVE: Vervet monkeys are common in most tree-rich areas of South Africa, but their absence from grassland and semi-desert areas of the country suggest potentially restricted and mosaic local population patterns that may have relevance to local phenotype patterns and selection. A portion of the mitochondrial DNA control region was sequenced to study patterns of genetic differentiation. METHODS: DNA was extracted, and mitochondrial DNA sequences were obtained from 101 vervet monkeys at 15 localities, which represent both an extensive (widely across the distribution range) and intensive (more than one troop at most of the localities) sampling strategy. Analyses utilized Arlequin 3.1, MEGA 6, BEAST v1.5.2, and Network V3.6.1. RESULTS: The dataset contained 26 distinct haplotypes, with six populations fixed for single haplotypes. Pairwise P-distance among population pairs showed significant differentiation among most population pairs, but with nonsignificant differences among populations within some regions. Populations were grouped into three broad clusters in a maximum likelihood phylogenetic tree and a haplotype network. These clusters correspond to i) north-western, northern, and north-eastern parts of the distribution range as well as the northern coastal belt; ii) central areas of the country; and iii) southern part of the Indian Ocean coastal belt and adjacent inland areas. CONCLUSIONS: Apparent patterns of genetic structure correspond to current and past distribution of suitable habitat, geographic barriers to gene flow, geographic distance, and female philopatry. However, further work on nuclear markers and other genomic data are necessary to confirm these results.


Assuntos
Chlorocebus aethiops/classificação , Chlorocebus aethiops/genética , DNA Mitocondrial/genética , Animais , Antropologia Física , Evolução Molecular , Feminino , Genética Populacional , Masculino , Filogenia , África do Sul
16.
Bull Environ Contam Toxicol ; 97(5): 593-600, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27289222

RESUMO

Lead (Pb) and calcium (Ca) concentrations were measured in fillet samples of longear sunfish (Lepomis megalotis) and redhorse suckers (Moxostoma spp.) collected in 2005-2012 from the Big River, which drains a historical mining area in southeastern Missouri and where a consumption advisory is in effect due to elevated Pb concentrations in fish. Lead tends to accumulated in Ca-rich tissues such as bone and scale. Concentrations of Pb in fish muscle are typically low, but can become elevated in fillets from Pb-contaminated sites depending in part on how much bone, scale, and skin is included in the sample. We used analysis-of-covariance to normalize Pb concentration to the geometric mean Ca concentration (415 ug/g wet weight, ww), which reduced variation between taxa, sites, and years, as was the number of samples that exceeded Missouri consumption advisory threshold (300 ng/g ww). Concentrations of Pb in 2005-2012 were lower than in the past, especially after Ca-normalization, but the consumption advisory is still warranted because concentrations were >300 ng/g ww in samples of both taxa from contaminated sites. For monitoring purposes, a simple linear regression model is proposed for estimating Ca-normalized Pb concentrations in fillets from Pb:Ca molar ratios as a way of reducing the effects of differing preparation methods on fillet Pb variation.


Assuntos
Cálcio/análise , Monitoramento Ambiental , Peixes/metabolismo , Chumbo/análise , Mineração , Rios/química , Animais , Cipriniformes/metabolismo , Produtos Pesqueiros/análise , Missouri , Perciformes/metabolismo , Fatores de Tempo , Poluentes Químicos da Água/análise
17.
J Virol ; 88(10): 5687-705, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24623416

RESUMO

UNLABELLED: African green monkeys (AGMs) are naturally infected with simian immunodeficiency virus (SIV) at high prevalence levels and do not progress to AIDS. Sexual transmission is the main transmission route in AGM, while mother-to-infant transmission (MTIT) is negligible. We investigated SIV transmission in wild AGMs to assess whether or not high SIV prevalence is due to differences in mucosal permissivity to SIV (i.e., whether the genetic bottleneck of viral transmission reported in humans and macaques is also observed in AGMs in the wild). We tested 121 sabaeus AGMs (Chlorocebus sabaeus) from the Gambia and found that 53 were SIV infected (44%). By combining serology and viral load quantitation, we identified 4 acutely infected AGMs, in which we assessed the diversity of the quasispecies by single-genome amplification (SGA) and documented that a single virus variant established the infections. We thus show that natural SIV transmission in the wild is associated with a genetic bottleneck similar to that described for mucosal human immunodeficiency virus (HIV) transmission in humans. Flow cytometry assessment of the immune cell populations did not identify major differences between infected and uninfected AGM. The expression of the SIV coreceptor CCR5 on CD4+ T cells dramatically increased in adults, being higher in infected than in uninfected infant and juvenile AGMs. Thus, the limited SIV MTIT in natural hosts appears to be due to low target cell availability in newborns and infants, which supports HIV MTIT prevention strategies aimed at limiting the target cells at mucosal sites. Combined, (i) the extremely high prevalence in sexually active AGMs, (ii) the very efficient SIV transmission in the wild, and (iii) the existence of a fraction of multiparous females that remain uninfected in spite of massive exposure to SIV identify wild AGMs as an acceptable model of exposed, uninfected individuals. IMPORTANCE: We report an extensive analysis of the natural history of SIVagm infection in its sabaeus monkey host, the African green monkey species endemic to West Africa. Virtually no study has investigated the natural history of SIV infection in the wild. The novelty of our approach is that we report for the first time that SIV infection has no discernible impact on the major immune cell populations in natural hosts, thus confirming the nonpathogenic nature of SIV infection in the wild. We also focused on the correlates of SIV transmission, and we report, also for the first time, that SIV transmission in the wild is characterized by a major genetic bottleneck, similar to that described for HIV-1 transmission in humans. Finally, we report here that the restriction of target cell availability is a major correlate of the lack of SIV transmission to the offspring in natural hosts of SIVs.


Assuntos
Infecções por Lentivirus/veterinária , Doenças dos Macacos/transmissão , Doenças dos Macacos/virologia , Vírus da Imunodeficiência Símia/isolamento & purificação , Animais , Chlorocebus aethiops , Análise por Conglomerados , Feminino , Citometria de Fluxo , Gâmbia , Genótipo , Infecções por Lentivirus/imunologia , Infecções por Lentivirus/transmissão , Infecções por Lentivirus/virologia , Subpopulações de Linfócitos/imunologia , Masculino , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Vírus da Imunodeficiência Símia/classificação , Vírus da Imunodeficiência Símia/genética
18.
PLoS Pathog ; 9(1): e1003011, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23349627

RESUMO

Pathogenesis studies of SIV infection have not been performed to date in wild monkeys due to difficulty in collecting and storing samples on site and the lack of analytical reagents covering the extensive SIV diversity. We performed a large scale study of molecular epidemiology and natural history of SIVagm infection in 225 free-ranging AGMs from multiple locations in South Africa. SIV prevalence (established by sequencing pol, env, and gag) varied dramatically between infant/juvenile (7%) and adult animals (68%) (p<0.0001), and between adult females (78%) and males (57%). Phylogenetic analyses revealed an extensive genetic diversity, including frequent recombination events. Some AGMs harbored epidemiologically linked viruses. Viruses infecting AGMs in the Free State, which are separated from those on the coastal side by the Drakensberg Mountains, formed a separate cluster in the phylogenetic trees; this observation supports a long standing presence of SIV in AGMs, at least from the time of their speciation to their Plio-Pleistocene migration. Specific primers/probes were synthesized based on the pol sequence data and viral loads (VLs) were quantified. VLs were of 10(4)-10(6) RNA copies/ml, in the range of those observed in experimentally-infected monkeys, validating the experimental approaches in natural hosts. VLs were significantly higher (10(7)-10(8) RNA copies/ml) in 10 AGMs diagnosed as acutely infected based on SIV seronegativity (Fiebig II), which suggests a very active transmission of SIVagm in the wild. Neither cytokine levels (as biomarkers of immune activation) nor sCD14 levels (a biomarker of microbial translocation) were different between SIV-infected and SIV-uninfected monkeys. This complex algorithm combining sequencing and phylogeny, VL quantification, serology, and testing of surrogate markers of microbial translocation and immune activation permits a systematic investigation of the epidemiology, viral diversity and natural history of SIV infection in wild African natural hosts.


Assuntos
Chlorocebus aethiops , Evolução Molecular , Variação Genética , Síndrome de Imunodeficiência Adquirida dos Símios/epidemiologia , Vírus da Imunodeficiência Símia/isolamento & purificação , Animais , Sequência de Bases , Feminino , Interações Hospedeiro-Patógeno , Masculino , Dados de Sequência Molecular , Taxa de Mutação , Recombinação Genética , Sequências Repetitivas de Ácido Nucleico , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/genética , África do Sul/epidemiologia
19.
Mol Phylogenet Evol ; 82 Pt B: 495-510, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24751996

RESUMO

Using complete mitochondrial genome sequences, we provide the first molecular analysis of the phylogenetic position of the yellow-tailed woolly monkey, Lagothrix flavicauda (a.k.a. Oreonax flavicauda), a critically endangered neotropical primate endemic to northern Perú. The taxonomic status and phylogenetic position of yellow-tailed woolly monkeys have been debated for many years, but in this study both Bayesian and maximum likelihood phylogenetic reconstructions unequivocally support a monophyletic woolly monkey clade that includes L. flavicauda as the basal taxon within the radiation. Bayesian dating analyses using several alternative calibrations suggest that the divergence of yellow-tailed woolly monkeys from other Lagothrix occurred in the Pleistocene, ∼2.1Ma, roughly 6.5 my after the divergence of woolly monkeys from their sister genus, Brachyteles. Additionally, comparative analysis of the cytochrome oxidase subunit 2 (COX2) gene shows that genetic distances between yellow-tailed woolly monkeys and other Lagothrix from across the genus' geographic distribution fall well within the range of between-species divergences seen in a large number of other platyrrhine primate genera at the same locus and outside the range of between-genus divergences. Our results thus confirm a position within Lagothrix for the yellow-tailed woolly monkey and strongly suggest that the name Oreonax be formally considered a synonym for this genus. This revision in taxonomic status does not change the dire conservation threats facing the yellow-tailed woolly monkey in Perú, where the remaining wild population is estimated at only ∼10,000 individuals living in a highly fragmented landscape.


Assuntos
Atelidae/classificação , Evolução Biológica , Filogenia , Animais , Atelidae/genética , Teorema de Bayes , DNA Mitocondrial/genética , Funções Verossimilhança , Modelos Genéticos , Peru , Análise de Sequência de DNA , América do Sul
20.
Environ Sci Technol ; 49(16): 9639-47, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26230836

RESUMO

Observations of reddish to "purple" discolored eggs in the ovaries of adult female blue catfish (Ictalurus furcatus) from the northern arm of Eufaula Lake, a eutrophic multiuse impoundment in east-central Oklahoma, were first reported in 2006. Blue catfish eggs are normally cream to light yellow. Reports peaked in 2007-2008 and declined through 2009-2010; purple eggs have not been reported between 2010 and 2014. In the laboratory, all tissues and fluids of affected fish were strongly orange-red fluorescent under UV illumination, with the fluorescence most apparent in the lipid-rich ovaries and eggs. The causative agent was isolated chromatographically and confirmed by mass spectrometry as stentorin (1,3,4,6,8,10,11,13-octahydroxy-2,5-diisopropyl-phenanthro[1,10,9,8,o,p,q,r,a]perylene-7,14-dione), the fluorescent, lipophilic pigment associated with the photoreceptor protein of the ciliated protozoan Stentor coeruleus (Heterotrichea; Stentoridae). Larval medaka (Orizias latipes) readily consumed S. coeruleus in the laboratory and were observed to fluoresce in the same manner as the affected blue catfish. Potential deleterious effects of stentorin bioaccumulation remain to be determined, as do the geographic extent and the identities of other fluorescent compounds isolated from catfish eggs and ovaries.


Assuntos
Ictaluridae/metabolismo , Ovário/fisiopatologia , Óvulo/metabolismo , Compostos Policíclicos/metabolismo , Animais , Feminino , Humanos , Lagos , Oklahoma , Raios Ultravioleta
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