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1.
Proc Natl Acad Sci U S A ; 121(30): e2319628121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012821

RESUMO

Heterotrophic protists are vital in Earth's ecosystems, influencing carbon and nutrient cycles and occupying key positions in food webs as microbial predators. Fossils and molecular data suggest the emergence of predatory microeukaryotes and the transition to a eukaryote-rich marine environment by 800 million years ago (Ma). Neoproterozoic vase-shaped microfossils (VSMs) linked to Arcellinida testate amoebae represent the oldest evidence of heterotrophic microeukaryotes. This study explores the phylogenetic relationship and divergence times of modern Arcellinida and related taxa using a relaxed molecular clock approach. We estimate the origin of nodes leading to extant members of the Arcellinida Order to have happened during the latest Mesoproterozoic and Neoproterozoic (1054 to 661 Ma), while the divergence of extant infraorders postdates the Silurian. Our results demonstrate that at least one major heterotrophic eukaryote lineage originated during the Neoproterozoic. A putative radiation of eukaryotic groups (e.g., Arcellinida) during the early-Neoproterozoic sustained by favorable ecological and environmental conditions may have contributed to eukaryotic life endurance during the Cryogenian severe ice ages. Moreover, we infer that Arcellinida most likely already inhabited terrestrial habitats during the Neoproterozoic, coexisting with terrestrial Fungi and green algae, before land plant radiation. The most recent extant Arcellinida groups diverged during the Silurian Period, alongside other taxa within Fungi and flowering plants. These findings shed light on heterotrophic microeukaryotes' evolutionary history and ecological significance in Earth's ecosystems, using testate amoebae as a proxy.


Assuntos
Ecossistema , Fósseis , Processos Heterotróficos , Filogenia , Biodiversidade , Evolução Biológica , Amebozoários/genética , Amebozoários/classificação , Amoeba/genética , Amoeba/classificação , Amoeba/fisiologia , Eucariotos/genética , Eucariotos/classificação
2.
Artigo em Inglês | MEDLINE | ID: mdl-38908504

RESUMO

CO2 exposure has been used to investigate the panicogenic response in patients with panic disorder. These patients are more sensitive to CO2, and more likely to experience the "false suffocation alarm" which triggers panic attacks. Imbalances in locus coeruleus noradrenergic (LC-NA) neurotransmission are responsible for psychiatric disorders, including panic disorder. These neurons are sensitive to changes in CO2/pH. Therefore, we investigated if LC-NA neurons are differentially activated after severe hypercapnia in mice. Further, we evaluated the participation of LC-NA neurons in ventilatory and panic-like escape responses induced by 20% CO2 in male and female wild type mice and two mouse models of altered LC-NA synthesis. Hypercapnia activates the LC-NA neurons, with males presenting a heightened level of activation. Mutant males lacking or with reduced LC-NA synthesis showed hypoventilation, while animals lacking LC noradrenaline present an increased metabolic rate compared to wild type in normocapnia. When exposed to CO2, males lacking LC noradrenaline showed a lower respiratory frequency compared to control animals. On the other hand, females lacking LC noradrenaline presented a higher tidal volume. Nevertheless, no change in ventilation was observed in either sex. CO2 evoked an active escape response. Mice lacking LC noradrenaline had a blunted jumping response and an increased freezing duration compared to the other groups. They also presented fewer racing episodes compared to wild type animals, but not different from mice with reduced LC noradrenaline. These findings suggest that LC-NA has an important role in ventilatory and panic-like escape responses elicited by CO2 exposure in mice.


Assuntos
Dióxido de Carbono , Hiperventilação , Locus Cerúleo , Norepinefrina , Animais , Locus Cerúleo/metabolismo , Locus Cerúleo/efeitos dos fármacos , Feminino , Masculino , Norepinefrina/metabolismo , Camundongos , Hipercapnia/metabolismo , Camundongos Endogâmicos C57BL , Pânico/efeitos dos fármacos , Pânico/fisiologia , Modelos Animais de Doenças , Transtorno de Pânico/metabolismo , Transtorno de Pânico/induzido quimicamente , Transtorno de Pânico/fisiopatologia , Camundongos Knockout , Caracteres Sexuais
3.
Sci Rep ; 13(1): 18639, 2023 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903898

RESUMO

In semi-arid environments, resources necessary for survival may be unevenly distributed across the landscape. Gould's wild turkeys (Meleagris gallopavo mexicana) are spatially restricted to mountainous semi-arid areas of southwestern United States and Mexico, and information on their distribution and habitat use is limited. We described how landcover type and topographical features influenced space use and habitat selection by Gould's wild turkeys in southeastern Arizona. We used GPS data from 51 Gould's wild turkeys to describe resource selection during 2016-2017 in southeastern Arizona, USA. We estimated home ranges and calculated resource selection functions using distance from landcover types, slope, aspect, and elevation at used locations and random locations within individual home ranges. Gould's wild turkeys selected areas closer to pine forest and water. Likewise, Gould's wild turkeys selected locations with moderate elevations of 1641 ± 235 m (range = 1223-2971 m), and on north and west facing slopes with a 10° ± 8.5 (range = 0.0-67.4°) incline. Our findings suggest that conserving portions of the landscape with appropriate topography and landcover types as described above will promote habitat availability for Gould's wild turkeys.


Assuntos
Animais Selvagens , Ecossistema , Animais , Arizona , Sudoeste dos Estados Unidos , México , Perus
4.
R Soc Open Sci ; 10(6): 230065, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37351500

RESUMO

This study investigated the possibility of using low-cost, handheld, retinal imaging devices for the automatic extraction of quantifiable measures of retinal blood vessels. Initially, the available handheld devices were compared using a Zeiss model eye incorporating a USAF resolution test chart to assess their optical properties. The only suitable camera of the five evaluated was the Horus DEC 200. This device was then subjected to a detailed evaluation in which images in human eyes taken from the handheld camera were compared in a quantitative analysis with those of the same eye from a Canon CR-DGi retinal desktop camera. We found that the Horus DEC 200 exhibited shortcomings in capturing images of human eyes by comparison with the Canon. More images were rejected as being unevaluable or suffering failures in automatic segmentation than with the Canon, and even after exclusion of affected images, the Horus yielded lower measurements of vessel density than the Canon. A number of issues affecting handheld cameras in general and some features of the Horus in particular have been identified that might contribute to the observed differences in performance. Some potential mitigations are discussed which might yield improvements in performance, thus potentially facilitating use of handheld retinal imaging devices for quantitative retinal microvascular measurements.

5.
PLoS One ; 17(9): e0266283, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36112656

RESUMO

Haloclavidae Verrill, 1899 is a family of burrowing sea anemones grouped within the superfamily Actinioidea (Rafinesque, 1815). Currently, it includes 30 species in 10 genera. Characters given for this family in descriptions of its taxa have not been consistent, with numerous exceptions to the expectations of the familial diagnosis. Previous phylogenetic analyses have shown that Haloclavidae is potentially a polyphyletic group, but resolution of relationships of the few representatives of Haloclavidae included in analyses has been problematic. Here we address questions of monophyly and affinity of Haloclavidae using three mitochondrial and two nuclear markers. We assess the monophyly of Haloclavidae in the context of all major lineages of Actiniaria Hertwig, 1882, emphasizing diversity of superfamily Actinioidea. We use parsimony-based character optimization to interpret the distribution of key traits in the superfamily. We find that Haloclavidae is not monophyletic and propose two new families, Peachiidae fam. nov. and Harenactidae fam. nov., while also retaining some species in the family Haloclavidae, so that taxonomy better reflects relationships and diversity of the group. In addition, we redescribe a species within the newly created Peachiidae, Peachia chilensis Carlgren, 1931. We use recent larval samples obtained in Antofagasta, Chile, and the histological slides from the original description to redescribe P. chilensis, to provide a complete account of cnidae, external, and internal morphology. Finally, we compare P. chilensis to other burrowing anemones found in Chile and provide an understanding of the genus Peachia that reflects recent phylogenetic perspective on diversity of anemones previously assigned to family Haloclavidae.


Assuntos
Anêmonas-do-Mar , Animais , Núcleo Celular/genética , Chile , Filogenia , Anêmonas-do-Mar/anatomia & histologia , Anêmonas-do-Mar/genética
6.
Animals (Basel) ; 11(8)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34438617

RESUMO

Our objective was to determine the impact of different habituation protocols on beef cattle behavior, physiology, and temperament in response to human handling. Beef heifers were exposed to three habituation strategies: (1) tactile stimulation (brushing) in the working chute for seven consecutive days (STI; n = 18); (2) passage through the working chute for seven consecutive days (CHU; n = 19) and; (3) no habituation (CON; n = 19). Individual heifer respiratory rate (RR; n/min), internal vaginal temperature (VAGT; °C), and blood cortisol were measured. Further, behavior parameters were observed to generate a behavior score, and heifer interaction with students and their behavioral responses were recorded. Habituation with STI and CHU resulted in improved numerical behavioral scores compared to CON, and greater (p ≤ 0.05) handling latencies. Vaginal temperature was decreased in STI compared to CHU and CONT (p ≤ 0.05). Cortisol concentration did not differ among treatments, but decreased (p ≤ 0.05) from the start of the experiment to 14 days after treatment initiation. Both habituation protocols showed benefits, but heifers that received the positive tactile stimulation in the chute had the greatest behavior improvements. Furthermore, these heifers responded more calmly during student-animal interactions in class, which is beneficial for the students' and animals' safety.

7.
Am J Physiol Lung Cell Mol Physiol ; 321(2): L466-L476, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34231389

RESUMO

Allergic asthma is a chronic airway inflammatory response to different triggers like inhaled allergens. Excessive ATP in fluids from patients with asthma is considered an inflammatory signal and an important autocrine/paracrine modulator of airway physiology. Here, we investigated the deleterious effect of increased extracellular ATP (eATP) concentration on the mucociliary clearance (MCC) effectiveness and determined the role of ATP releasing channels during airway inflammation in an ovalbumin (OVA)-sensitized mouse model. Our allergic mouse model exhibited high levels of eATP measured in the tracheal fluid with a luciferin-luciferase assay and reduced MCC velocity determined by microspheres tracking in the trachea ex vivo. Addition of ATP had a dual effect on MCC, where lower ATP concentration (µM) increased microspheres velocity, whereas higher concentration (mM) transiently stopped microspheres movement. Also, an augmented ethidium bromide uptake by the allergic tracheal airway epithelium suggests an increase in ATP release channel functionality during inflammatory conditions. The use of carbenoxolone, a nonspecific inhibitor of connexin and pannexin1 channels reduced the eATP concentration in the allergic mouse tracheal fluid and dye uptake by the airway epithelium, providing evidence that these ATP release channels are facilitating the net flux of ATP to the lumen during airway inflammation. However, only the specific inhibition of pannexin1 with 10Panx peptide significantly reduced eATP in bronchoalveolar lavage and decreased airway hyperresponsiveness in OVA-allergic mouse model. These data provide evidence that blocking eATP may be a pharmacological alternative to be explored in rescue therapy during episodes of airflow restriction in patients with asthma.


Assuntos
Trifosfato de Adenosina/imunologia , Asma/imunologia , Carbenoxolona/farmacologia , Conexinas/imunologia , Proteínas do Tecido Nervoso/imunologia , Mucosa Respiratória/imunologia , Traqueia/imunologia , Animais , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/patologia , Conexinas/antagonistas & inibidores , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Peptídeos/imunologia , Peptídeos/farmacologia , Mucosa Respiratória/patologia , Traqueia/patologia
8.
Environ Monit Assess ; 192(10): 648, 2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32951088

RESUMO

Here, we present a framework for a beach litter monitoring process, based on free and open-source software (FOSS), which allows customization for any sampling design. The framework was developed by means of a GIS project (QGIS), a GIS collector (QField), and an R code, allowing further adjustments according to the area to be surveyed and research questions. The aim is to improve data collection, accessibility, and interoperability, as well as to help to fill the currently existing gap between fieldwork and data analysis, preventing typos and allowing better data processing. Therefore, it is expected to take less than an hour from ending fieldwork to obtaining up-to-date products. To test the developed open-source geospatial framework, it was applied in different sectors and dates on an important southern Brazilian touristic beach. Results obtained from the open-source geospatial framework application produce baseline information on beach litter issues, such as amounts, sources, and spatial and temporal patterns. Adoption of the framework can facilitate data collection by local and regional stakeholders, and the results obtained from it can be applied to support management strategies. For researchers, it produces spatialized data for each item in an already tidy format, which can be used for robust and complex models. A series of supplementary files support reproducibility and provide a guide to future users.


Assuntos
Praias , Plásticos , Brasil , Monitoramento Ambiental , Reprodutibilidade dos Testes , Resíduos/análise
9.
BMC Biol ; 18(1): 84, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620168

RESUMO

BACKGROUND: Heliconius butterflies are widely distributed across the Neotropics and have evolved a stunning array of wing color patterns that mediate Müllerian mimicry and mating behavior. Their rapid radiation has been strongly influenced by hybridization, which has created new species and allowed sharing of color patterning alleles between mimetic species pairs. While these processes have frequently been observed in widespread species with contiguous distributions, many Heliconius species inhabit patchy or rare habitats that may strongly influence the origin and spread of species and color patterns. Here, we assess the effects of historical population fragmentation and unique biology on the origins, genetic health, and color pattern evolution of two rare and sparsely distributed Brazilian butterflies, Heliconius hermathena and Heliconius nattereri. RESULTS: We assembled genomes and re-sequenced whole genomes of eight H. nattereri and 71 H. hermathena individuals. These species harbor little genetic diversity, skewed site frequency spectra, and high deleterious mutation loads consistent with recent population bottlenecks. Heliconius hermathena consists of discrete, strongly isolated populations that likely arose from a single population that dispersed after the last glacial maximum. Despite having a unique color pattern combination that suggested a hybrid origin, we found no genome-wide evidence that H. hermathena is a hybrid species. However, H. hermathena mimicry evolved via introgression, from co-mimetic Heliconius erato, of a small genomic region upstream of the color patterning gene cortex. CONCLUSIONS: Heliconius hermathena and H. nattereri population fragmentation, potentially driven by historical climate change and recent deforestation, has significantly reduced the genetic health of these rare species. Our results contribute to a growing body of evidence that introgression of color patterning alleles between co-mimetic species appears to be a general feature of Heliconius evolution.


Assuntos
Evolução Biológica , Borboletas/genética , Ecossistema , Genoma , Hibridização Genética , Animais , Brasil , Feminino , Masculino , Sequenciamento Completo do Genoma
10.
Intern Med J ; 50(6): 691-697, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31180163

RESUMO

BACKGROUND: Respiratory infections are one of the leading causes of mortality, and comorbid conditions play a significant role in the severity and fatality of these infections. AIMS: We evaluated the Charlson Comorbidity Index (CCI) score and possible predictors of mortality in hospitalised patients with severe acute respiratory infection (SARI), aiming to test if the CCI is a valid in-hospital prognostic indicator. METHODS: Patients older than 14 years, hospitalised from 2010 to 2016 due to SARI by viral infection and who were submitted to respiratory virus testing were included. We assessed comorbidity retrospectively through chart review and calculated four variants of the CCI. RESULTS: Of the 291 patients assessed, 72.8% (n = 212) presented comorbidities, and 24% died (n = 70). The most recurrent comorbidities were chronic pulmonary disease (n = 76/212, 36%) and HIV (n = 50/212, 23.6%). The 1994 age-adjusted CCI predicted in-hospital mortality in SARI patients (P = 0.04), and HIV was associated with in-hospital mortality (P = 0.032). CONCLUSIONS: The comorbidity scores used to assess mortality risk in hospitalised patients with SARI displayed poor results, but HIV infection was considered a marker of severity. However, other factors should be considered in order to compose a score system that allows us to specifically assess the risk of mortality in patients with SARI.


Assuntos
Infecções por HIV , Infecções Respiratórias , Comorbidade , Hospitais , Humanos , Prognóstico , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Medição de Risco
11.
Clin Infect Dis ; 71(4): 1000-1007, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31773126

RESUMO

BACKGROUND: Campylobacter infection is associated with impaired growth of children, even in the absence of symptoms. To examine the underlying mechanisms, we evaluated associations between Campylobacter infection, linear growth, and fecal microbial community features in a prospective birth cohort of 271 children with a high burden of diarrhea and stunting in the Amazonian lowlands of Peru. METHODS: Campylobacter was identified using a broadly reactive, genus-specific enzyme-linked immunosorbent assay. 16S rRNA-based analyses were used to identify bacterial taxa in fecal samples at ages 6, 12, 18, and 24 months (N = 928). Associations between infection, growth, and gut microbial community composition were investigated using multiple linear regression adjusting for within-child correlations, age, and breastfeeding. Indicator species analyses identified taxa specifically associated with Campylobacter burden. RESULTS: Ninety-three percent (251) of children had Campylobacter present in asymptomatic fecal samples during the follow-up period. A 10% increase in the proportion of stools infected was associated with mean reductions of 0.02 length-for-age z scores (LAZ) at 3, 6, and 9 months thereafter (P < .01). We identified 13 bacterial taxa indicative of cumulative Campylobacter burden and 14 taxa significantly associated with high or low burden of enteroaggregative Escherichia coli, norovirus, or Giardia. CONCLUSIONS: Campylobacter infection is common in this cohort and associated with changes in microbial community composition. These results support the notion that disruptions to the fecal microbiota may help explain the observed effects of asymptomatic infections on growth in early life.


Assuntos
Infecções por Campylobacter , Campylobacter , Microbioma Gastrointestinal , Adolescente , Adulto , Infecções por Campylobacter/epidemiologia , Criança , Fezes , Feminino , Humanos , Lactente , Peru/epidemiologia , Estudos Prospectivos , RNA Ribossômico 16S/genética , Adulto Jovem
12.
Clin Infect Dis ; 71(4): 989-999, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31773127

RESUMO

BACKGROUND: Detrimental effects of diarrhea on child growth and survival are well documented, but details of the underlying mechanisms remain poorly understood. Recent evidence demonstrates that perturbations to normal development of the gut microbiota in early life may contribute to growth faltering and susceptibility to related childhood diseases. We assessed associations between diarrhea, gut microbiota configuration, and childhood growth in the Peruvian Amazon. METHODS: Growth, diarrhea incidence, illness, pathogen infection, and antibiotic exposure were assessed monthly in a birth cohort of 271 children aged 0-24 months. Gut bacterial diversity and abundances of specific bacterial taxa were quantified by sequencing 16S rRNA genes in fecal samples collected at 6, 12, 18, and 24 months. Linear and generalized linear models were used to determine whether diarrhea was associated with altered microbiota and, in turn, if features of the microbiota were associated with the subsequent risk of diarrhea. RESULTS: Diarrheal frequency, duration, and severity were negatively associated with bacterial diversity and richness (P < .05). Children born stunted (length-for-age z-score [LAZ] ≤ -2) who were also severely stunted (LAZ ≤ -3) at the time of sampling exhibited the greatest degree of diarrhea-associated reductions in bacterial diversity and the slowest recovery of bacterial diversity after episodes of diarrhea. Increased bacterial diversity was predictive of reduced subsequent diarrhea from age 6 to 18 months. CONCLUSIONS: Persistent, severe growth faltering may reduce the gut microbiota's resistance and resilience to diarrhea, leading to greater losses of diversity and longer recovery times. This phenotype, in turn, denotes an increased risk of future diarrheal disease and growth faltering.


Assuntos
Microbioma Gastrointestinal , Adolescente , Adulto , Criança , Pré-Escolar , Diarreia/epidemiologia , Fezes , Humanos , Lactente , Recém-Nascido , Peru/epidemiologia , RNA Ribossômico 16S/genética , Adulto Jovem
13.
Ecol Evol ; 8(11): 5530-5540, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29938071

RESUMO

Mangroves of the semiarid Caatinga region of northeastern Brazil are being rapidly converted to shrimp pond aquaculture. To determine ecosystem carbon stocks and potential greenhouse gas emissions from this widespread land use, we measured carbon stocks of eight mangrove forests and three shrimp ponds in the Acaraú and Jaguaribe watersheds in Ceará state, Brazil. The shrimp ponds were paired with adjacent intact mangroves to ascertain carbon losses and potential emissions from land conversion. The mean total ecosystem carbon stock of mangroves in this semiarid tropical landscape was 413 ± 94 Mg C/ha. There were highly significant differences in the ecosystem carbon stocks between the two sampled estuaries suggesting caution when extrapolating carbon stock across different estuaries even in the same landscape. Conversion of mangroves to shrimp ponds resulted in losses of 58%-82% of the ecosystem carbon stocks. The mean potential emissions arising from mangrove conversion to shrimp ponds was 1,390 Mg CO2e/ha. Carbon losses were largely from soils which accounted for 81% of the total emission. Losses from soils >100 cm in depth accounted for 33% of the total ecosystem carbon loss. Soil carbon losses from shrimp pond conversion are equivalent to about 182 years of soil carbon accumulation. Losses from mangrove conversion are about 10-fold greater than emissions from conversion of upland tropical dry forest in the Brazilian Caatinga underscoring the potential value for their inclusion in climate change mitigation activities.

14.
Anim Behav Cogn ; 5(1): 9-18, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32864425

RESUMO

Human children will select a novel object from among a group of known objects when presented with a novel object name. This disambiguation by exclusion may facilitate new name-object mappings and may play a role in the rapid word learning shown by young children. Animals including dogs, apes, monkeys, and birds make similar exclusion choices. However, evidence regarding whether children and nonhuman animals learn new associations through choice by exclusion is mixed. In the present study we dissociate choice by exclusion from learning by exclusion in rhesus monkeys using a paired-associate task. In experiment 1, monkeys demonstrated choice by exclusion by choosing a novel comparison image from among known comparison images when presented with a novel sample image. In experiment 2, monkeys failed to benefit from choice by exclusion in learning new sets of paired associates. Monkeys learned new sets of four paired associates by trial and error alone or by a combination of exclusion and trial and error. Despite choosing correctly by exclusion on almost 100% of opportunities, monkeys did not learn any faster by exclusion than by trial and error alone. These results indicate that monkeys chose, but do not learn, through exclusion, highlighting the importance of separately evaluating choice and learning in studies of exclusion in word learning.

15.
J Am Assoc Lab Anim Sci ; 54(4): 399-404, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26224440

RESUMO

Listeria monocytogenes is an endemic agent in the primate population at the California National Primate Research Center and has been associated with both sporadic cases and a general outbreak of pregnancy failures. The primary objective of this study was to verify the incidence of L. monocytogenes-associated abortion and fetal deaths in the Center's outdoor breeding colony. In addition, we sought to compare the group of female macaques that presented with Listeria-associated abortion with both those with nonlisteria-associated abortion and animals with successful pregnancy outcome. We calculated the incidence of L. monocytogenes-associated abortion and stillbirth by dividing the number of positive L. monocytogenes cultures from aborted fetuses by the number of pregnant female macaques from 1989 through 2009. To compare the pregnancy outcome of female macaques that have presented L. monocytogenes-associated abortion and stillbirth, we created 2 control groups: female macaques with successful pregnancy outcomes during the 1999 breeding season and animals with nonlisteria-associated pregnancy failure. These macaques were followed for 2 subsequent breeding seasons. The results showed a range in the incidence of L. monocytogenes-associated abortion and stillbirth from 0% to 8.39% throughout the 1989 to 2009 breeding seasons. In addition, the Listeria-associated abortion group did not present statistically significant differences in fertility and abortion rates when compared with the control groups. We conclude that although L. monocytogenes is an endemic agent at the Center's outdoor breeding colony, the agent's incidence varied in significance. Furthermore, an episode of L. monocytogenes-associated abortion did not affect subsequent pregnancies.


Assuntos
Aborto Animal/microbiologia , Listeria monocytogenes/fisiologia , Listeriose/veterinária , Macaca mulatta , Doenças dos Macacos/microbiologia , Natimorto/veterinária , Aborto Animal/epidemiologia , Aborto Animal/etiologia , Animais , California/epidemiologia , Surtos de Doenças , Feminino , Incidência , Doenças dos Macacos/epidemiologia , Gravidez
16.
J Exp Biol ; 217(Pt 14): 2462-7, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24737768

RESUMO

The polarisation of light is used by many species of cephalopods and crustaceans to discriminate objects or to communicate. Most visual systems with this ability, such as that of the fiddler crab, include receptors with photopigments that are oriented horizontally and vertically relative to the outside world. Photoreceptors in such an orthogonal array are maximally sensitive to polarised light with the same fixed e-vector orientation. Using opponent neural connections, this two-channel system may produce a single value of polarisation contrast and, consequently, it may suffer from null points of discrimination. Stomatopod crustaceans use a different system for polarisation vision, comprising at least four types of polarisation-sensitive photoreceptor arranged at 0, 45, 90 and 135 deg relative to each other, in conjunction with extensive rotational eye movements. This anatomical arrangement should not suffer from equivalent null points of discrimination. To test whether these two systems were vulnerable to null points, we presented the fiddler crab Uca heteropleura and the stomatopod Haptosquilla trispinosa with polarised looming stimuli on a modified LCD monitor. The fiddler crab was less sensitive to differences in the degree of polarised light when the e-vector was at -45 deg than when the e-vector was horizontal. In comparison, stomatopods showed no difference in sensitivity between the two stimulus types. The results suggest that fiddler crabs suffer from a null point of sensitivity, while stomatopods do not.


Assuntos
Braquiúros/fisiologia , Crustáceos/fisiologia , Células Fotorreceptoras de Invertebrados/fisiologia , Visão Ocular/fisiologia , Animais , Comportamento Animal , Movimentos Oculares , Luz
17.
Nat Genet ; 45(2): 208-13, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23291585

RESUMO

To identify susceptibility loci for visceral leishmaniasis, we undertook genome-wide association studies in two populations: 989 cases and 1,089 controls from India and 357 cases in 308 Brazilian families (1,970 individuals). The HLA-DRB1-HLA-DQA1 locus was the only region to show strong evidence of association in both populations. Replication at this region was undertaken in a second Indian population comprising 941 cases and 990 controls, and combined analysis across the three cohorts for rs9271858 at this locus showed P(combined) = 2.76 × 10(-17) and odds ratio (OR) = 1.41, 95% confidence interval (CI) = 1.30-1.52. A conditional analysis provided evidence for multiple associations within the HLA-DRB1-HLA-DQA1 region, and a model in which risk differed between three groups of haplotypes better explained the signal and was significant in the Indian discovery and replication cohorts. In conclusion, the HLA-DRB1-HLA-DQA1 HLA class II region contributes to visceral leishmaniasis susceptibility in India and Brazil, suggesting shared genetic risk factors for visceral leishmaniasis that cross the epidemiological divides of geography and parasite species.


Assuntos
Predisposição Genética para Doença/genética , Cadeias alfa de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Leishmaniose Visceral/genética , Brasil , Eletroforese em Gel de Ágar , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos/genética , Humanos , Índia , Modelos Lineares , Razão de Chances , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único/genética
18.
Mov Disord ; 20(4): 479-484, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15641013

RESUMO

We report on a large Brazilian kindred with young-onset parkinsonism due to either a homozygous or heterozygous mutation in parkin. A total of 6 members were affected: 5 were homozygous and 1 heterozygous for a deletion in exon 4. Two other heterozygotes also had extrapyramidal signs. All affected subjects showed characteristic features of parkin disease with foot dystonia and an excellent response to levodopa complicated by motor fluctuations and dyskinesia within 3 years of therapy. Careful clinical follow-up over 10 years showed the phenotype was similar in all the homozygotes with asymmetrical limb bradykinesia and early walking difficulties. Some acceleration of disability was observed in some of the cases as they entered the third decade of illness, but dementia was absent.


Assuntos
Heterozigoto , Transtornos Parkinsonianos/etnologia , Transtornos Parkinsonianos/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Antiparkinsonianos/efeitos adversos , Brasil , Análise Mutacional de DNA , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/fisiopatologia , Éxons/genética , Feminino , Seguimentos , Pé/fisiopatologia , Genótipo , Humanos , Levodopa/efeitos adversos , Masculino , Transtornos Parkinsonianos/tratamento farmacológico , Linhagem , Mutação Puntual/genética
19.
J Leukoc Biol ; 73(3): 356-62, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12629149

RESUMO

Eosinophils are important inflammatory cells in allergic diseases. In the present study, we have investigated the effects of CCL22 on the recruitment of eosinophils in vivo and in vitro. CCL22 induced a dose- and time-dependent recruitment of eosinophils into the pleural cavity of mice, and this was dependent on the release of platelet-activating factor (PAF) and subsequent generation of CCL11. However, in an allergic pleurisy model, an anti-CCL22 polyclonal antibody given during sensitization or before challenge had no significant effect on eosinophil recruitment. CCL22 did not induce eosinophil chemotaxis in vitro but was able to induce eosinophil degranulation in vitro and in vivo. In conclusion, we show that although exogenously added CCL22 may induce eosinophil migration in vivo via release of PAF and CCL11 (eotaxin), endogenous production of CCL22 does not drive eosinophil migration during allergic inflammation. However, CCL22 may be an important activator of eosinophils once these cells have migrated into tissue.


Assuntos
Quimiocinas CC/farmacologia , Quimiotaxia/efeitos dos fármacos , Eosinófilos/citologia , Pleurisia/patologia , Receptores Acoplados a Proteínas G , Animais , Anticorpos/farmacologia , Degranulação Celular/efeitos dos fármacos , Quimiocina CCL11 , Quimiocina CCL22 , Quimiocinas CC/administração & dosagem , Quimiocinas CC/imunologia , Quimiocinas CC/fisiologia , Fatores Quimiotáticos de Eosinófilos/imunologia , Fatores Quimiotáticos de Eosinófilos/fisiologia , Hipersensibilidade/patologia , Leucotrieno B4/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Glicoproteínas da Membrana de Plaquetas/genética , Glicoproteínas da Membrana de Plaquetas/fisiologia , Pleurisia/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/fisiologia
20.
Am J Primatol ; 59(3): 123-8, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12619046

RESUMO

The rhesus macaque breeding colony of the Oswaldo Cruz Foundation (FIOCRUZ) was established in 1932 from a founding stock of 100 animals. This population has remained closed to new animal introductions for almost 70 years. A serologic survey was performed to determine the prevalence of antibodies to selected viruses as a first approach to identifying viral pathogens endemic in this population. Banked serum samples were tested for antibodies to simian immunodeficiency virus (SIV), simian T-lymphotropic virus (STLV), simian type D retrovirus (SRV), cercopithecine herpesvirus type-1 (B virus), rhesus cytomegalovirus (RhCMV), measles virus (MV), and hepatitis A virus (HAV). All samples were negative for antibodies against the simian retroviruses. The overall prevalence of antibodies was 95% for RhCMV, 45% for B virus, 35% for HAV, and 1% for MV. Prevalence was found to vary by age group.


Assuntos
Anticorpos Antivirais/sangue , Macaca fascicularis/virologia , Macaca mulatta/imunologia , Macaca mulatta/virologia , Doenças dos Macacos/virologia , Animais , Betaretrovirus/isolamento & purificação , Brasil/epidemiologia , Citomegalovirus/isolamento & purificação , Feminino , Vírus da Hepatite A/isolamento & purificação , Herpesvirus Cercopitecino 1/isolamento & purificação , Masculino , Vírus do Sarampo/isolamento & purificação , Doenças dos Macacos/epidemiologia , Doenças dos Macacos/imunologia , Estudos Soroepidemiológicos , Vírus da Imunodeficiência Símia/isolamento & purificação , Vírus Linfotrópico T Tipo 1 de Símios/isolamento & purificação
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