943 resultados para NON-HUMAN PRIMATE


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Dentro del marco del aborto involuntario recurrente (AIR), se han propuesto causas autoinmunes y alogénicas, e implementación de terapias como la inmunización activa con leucocitos alogénicos de la pareja o de donantes. La evidencia disponible en cuanto a la efectividad de estos tratamientos es contradictoria, por lo que se desea realizar una revisión sistemática para evaluar la efectividad de la inmunización activa con leucocitos alogénicos de la pareja o de donantes para esta condición. Se realizó un estudio tipo revisión sistemática de la literatura, usando las siguientes bases de datos: Medline, Embase, Cochrane Library y Scielo. Se realizó una búsqueda a través del registro de ensayos clínicos del Instituto Nacional de Salud de los Estados Unidos (www.clinicaltrials.gov) y, una búsqueda manual a través de las referencias de los estudios seleccionados siguiendo la estrategia de bola de nieve. Se seleccionaron ensayos clínicos y estudios de cohorte analítica, en idioma inglés y español. Se realizó un análisis cuantitativo de la información por medio de un metaanálisis. El tratamiento inmunomodulador con linfocitos puede considerarse como una terapia efectiva para mantener la gestación y lograr recién nacido vivo según resultados estadísticos; sin embargo la calidad de los estudios incluidos es baja, por lo que no se aconseja para la práctica rutinaria. Se sugiere la realización de estudios con metodologías robustas y que apoyen los resultados presentados en esta investigación.

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A central obstacle to the design of a global HIV-1 vaccine is virus diversity. Pathogen diversity is not unique to HIV-1, and has been successfully conquered in other fields by the creation of vaccine cocktails. Here we describe the testing of an HIV-1 envelope cocktail vaccine. Six macaques received the vaccine, delivered by successive immunizations with recombinant DNA, recombinant vaccinia virus and recombinant envelope proteins. Following vaccination, animals developed a diversity of anti-envelope antibody binding and neutralizing activities toward proteins and viruses that were not represented by sequence in the vaccine. T-cells were also elicited, as measured by gamma-interferon production assays with envelope-derived peptide pools. Vaccinated and control animals were then challenged with the heterologous pathogenic SHIV, 89.6P. Vaccinated monkeys experienced significantly lower virus titers and better maintenance of CD4+ T-cells than unvaccinated controls. The B- and T-cell immune responses were far superior post-challenge in the vaccinated group. Four of six vaccinated animals and only one of six control animals survived a 44-week observation period post-challenge. The present report is the first to describe pathogenic SHIV disease control mediated by a heterologous HIV-1 vaccine, devoid of 89.6 or SIV derivatives.

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The circadian system consists of multiple oscillators organized hierarchically, with the suprachiasmatic nucleus (SCN) as the master oscillator to mammalians. There are lots of evidences that each SCN cell is an oscillator and that entrainment depends upon coupling degree between them. Knowledge of the mechanism of coupling between the SCN cells is essential for understanding entrainment and expression of circadian rhythms, and thus promote the development of new treatments for circadian rhythmicity disorders, which may cause various diseases. Some authors suggest that the dissociation model of circadian rhythm activity of rats under T22, period near the limit of synchronization, is a good model to induce internal desynchronization, and in this way, enhance knowledge about the coupling mechanism. So, in order to evaluate the pattern of the motor activity circadian rhythm of marmosets, Callithrix jacchus, in light-dark cycles at the lower limit of entrainment, two experiments were conducted: 1) 6 adult females were submitted to the LD symmetric cycles T21, T22 and T21.5 for 60, 35 and 48 days, respectively; 2) 4 male and 4 female adults were subjected to T21 for 24 days followed by 18 days of LL, and then back to T21 for 24 days followed by 14 days of LL. Vocalizations of all animals and motor activity of each one of them were continuously recorded throughout the experiments, but the vocalizations were recorded only in Experiment 1. Under the Ts shorter than 24 h, two simultaneous circadian components appeared in motor activity, one with the same period of LD cycle, named light-entrained component, and the other in free-running, named non-light-entrained component. Both components were displayed for all the animals in T21, five animals (83.3%) in T21.5 and two animals (33.3%) in T22. For vocalizations both components were observed under the three Ts. Due to the different characteristics of these components we suggest that dissociation is result of partial synchronization to the LD cycle, wherein at least one group oscillator is synchronized to the LD by relative coordination and masking processes, while at least another group of oscillators is in free-running, but also under the influence of masking by the LD. As the T21 h was the only cycle able to promote the emergence of both circadian components in circadian rhythms of all Callithrix jacchus, this was then considered the lower entrainment limit of LD cycle promoter of dissociation in circadian rhythmicity of this species, and then suggested as a non-human primate model for forced desynchronization

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Several studies have assessed the morphology and thickness of hybrid layer, the dentin bend strengths as well as sealing ability of dentin adhesive systems. However, few in vivo studies have evaluated the biocompatibility of the adhesive systems following application to deep dentin or directly to the pulp of human teeth. Many studies performed in non-human primate teeth or teeth of rats have reported pulp healing and dentin bridging following pulp capping with bonding agents. In addition, a few clinical and radiographical reports of the success of resin pulp capping have been described in the dental literature.Objectives: the aim of this review was to evaluate the literature on pulp responses following total acid etching and application of adhesive resins on deep cavities or pulp exposures. In addition, the clinical/radiographical evidence for the apparent success of vital pulp therapy and results obtained from animal and human studies were compared and discussed.Significance and conclusions: the self-etching adhesive systems may be useful and safe when applied on dentin, In contrast, persistent inflammatory reactions as well as delay in pulpal healing and failure of dentin bridging were seen in human pulps capped with bonding agents. The results observed in animal teeth cannot be directly extrapolated to human clinical conditions. Consequently, vital pulp therapy using acidic agents and adhesive resins seems to be contraindicated. (C) 2000 Academy of Dental Materials. Published by Elsevier B.V. Ltd. All rights reserved.

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Background: The accumulation of pus in the orbit originating from an infected dental root is classified as odontogenic intraorbital abscess. Methods: Clinical, laboratory, and image evaluation of a non-human primate was performed. Results: The patient was cured after surgical therapy. Conclusions: This represents the first report of an odontogenic periodontal abscess in Cebus apella. © 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pós-graduação em Medicina Veterinária - FMVZ

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The subdivisions of the medial geniculate complex can be distinguished based on the immunostaining of calcium-binding proteins and by the properties of the neurons within each subdivision. The possibility of changes in neurochemistry in this and other central auditory areas are important aspects to understand the basis that contributing to functional variations determined by environmental cycles or the animal's cycles of activity and rest. This study investigated, for the first time, day/night differences in the amounts of parvalbumin-, calretinin- and calbindin-containing neurons in the thalamic auditory center of a non-human primate, Sapajus apella. The immunoreactivity of the PV-IR, CB-IR and CR-IR neurons demonstrated different distribution patterns among the subdivisions of the medial geniculate. Moreover, a high number of CB- and CR-IR neurons were found during day, whereas PV-IR was predominant at night. We conclude that in addition to the chemical heterogeneity of the medial geniculate nucleus with respect to the expression of calcium-binding proteins, expression also varied relative to periods of light and darkness, which may be important for a possible functional adaptation of central auditory areas to environmental changes and thus ensure the survival and development of several related functions.

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We previously reported the development of a lethal myeloid sarcoma in a non-human primate model utilizing retroviral vectors to genetically modify hematopoietic stem and progenitor cells. This leukemia was characterized by insertion of the vector provirus into the BCL2A1 gene, with resultant BCL2A1 over-expression. There is little information on the role of this anti-apoptotic member of the BCL2 family in hematopoiesis or leukemia induction. Therefore we studied the impact of Bcl2a1a lentiviral over-expression on murine hematopoietic stem and progenitor cells. We demonstrated the anti-apoptotic function of this protein in hematopoietic cells, but did not detect any impact of Bcl2a1a on in vitro cell growth or cell cycle kinetics. In vivo, we showed a higher propensity of HSCs over-expressing Bcl2a1a to engraft and contribute to hematopoiesis. Mice over-expressing Bcl2a1a in the hematologic compartment eventually developed an aggressive malignant disease characterized as a leukemia/lymphoma of B-cell origin. Secondary transplants carried out to investigate the primitive origin of the disease revealed the leukemia was transplantable. Thus, Bcl2a1 should be considered as a protooncogene with a potential role in both lymphoid and myeloid leukemogenesis, and a concerning site for insertional activation by integrating retroviral vectors utilized in hematopoietic stem cell gene therapy.

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Background An adult male Brachyteles arachanoides, kept in captivity since 1990, was found dead without apparent clinical evidence. Methods Necropsy report, histopathology, immunohistochemistry, and ultrastructural examination were conducted. Results Pulmonary syncytial cells were positive for respiratory syncytial virus (RSV), and ultrastructural examination revealed viral particles inside macrophages compatible with the Paramyxoviridae family. Conclusions Muriquis are susceptible to RSV pneumonia followed by respiratory distress syndrome and death.

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Introduction. Postnatal neurogenesis in the hippocampal dentate gyrus, can be modulated by numerous determinants, such as hormones, transmitters and stress. Among the factors positively interfering with neurogenesis, the complexity of the environment appears to play a particularly striking role. Adult mice reared in an enriched environment produce more neurons and exhibit better performance in hippocampus-specific learning tasks. While the effects of complex environments on hippocampal neurogenesis are well documented, there is a lack of information on the effects of living under socio-sensory deprivation conditions. Due to the immaturity of rats and mice at birth, studies dealing with the effects of environmental enrichment on hippocampal neurogenesis were carried out in adult animals, i.e. during a period of relatively low rate of neurogenesis. The impact of environment is likely to be more dramatic during the first postnatal weeks, because at this time granule cell production is remarkably higher than at later phases of development. The aim of the present research was to clarify whether and to what extent isolated or enriched rearing conditions affect hippocampal neurogenesis during the early postnatal period, a time window characterized by a high rate of precursor proliferation and to elucidate the mechanisms underlying these effects. The experimental model chosen for this research was the guinea pig, a precocious rodent, which, at 4-5 days of age can be independent from maternal care. Experimental design. Animals were assigned to a standard (control), an isolated, or an enriched environment a few days after birth (P5-P6). On P14-P17 animals received one daily bromodeoxyuridine (BrdU) injection, to label dividing cells, and were sacrificed either on P18, to evaluate cell proliferation or on P45, to evaluate cell survival and differentiation. Methods. Brain sections were processed for BrdU immunhistochemistry, to quantify the new born and surviving cells. The phenotype of the surviving cells was examined by means of confocal microscopy and immunofluorescent double-labeling for BrdU and either a marker of neurons (NeuN) or a marker of astrocytes (GFAP). Apoptotic cell death was examined with the TUNEL method. Serial sections were processed for immunohistochemistry for i) vimentin, a marker of radial glial cells, ii) BDNF (brain-derived neurotrofic factor), a neurotrophin involved in neuron proliferation/survival, iii) PSA-NCAM (the polysialylated form of the neural cell adhesion molecule), a molecule associated with neuronal migration. Total granule cell number in the dentate gyrus was evaluated by stereological methods, in Nissl-stained sections. Results. Effects of isolation. In P18 isolated animals we found a reduced cell proliferation (-35%) compared to controls and a lower expression of BDNF. Though in absolute terms P45 isolated animals had less surviving cells than controls, they showed no differences in survival rate and phenotype percent distribution compared to controls. Evaluation of the absolute number of surviving cells of each phenotype showed that isolated animals had a reduced number of cells with neuronal phenotype than controls. Looking at the location of the new neurons, we found that while in control animals 76% of them had migrated to the granule cell layer, in isolated animals only 55% of the new neurons had reached this layer. Examination of radial glia cells of P18 and P45 animals by vimentin immunohistochemistry showed that in isolated animals radial glia cells were reduced in density and had less and shorter processes. Granule cell count revealed that isolated animals had less granule cells than controls (-32% at P18 and -42% at P45). Effects of enrichment. In P18 enriched animals there was an increase in cell proliferation (+26%) compared to controls and a higher expression of BDNF. Though in both groups there was a decline in the number of BrdU-positive cells by P45, enriched animals had more surviving cells (+63) and a higher survival rate than controls. No differences were found between control and enriched animals in phenotype percent distribution. Evaluation of the absolute number of cells of each phenotype showed that enriched animals had a larger number of cells of each phenotype than controls. Looking at the location of cells of each phenotype we found that enriched animals had more new neurons in the granule cell layer and more astrocytes and cells with undetermined phenotype in the hilus. Enriched animals had a higher expression of PSA-NCAM in the granule cell layer and hilus Vimentin immunohistochemistry showed that in enriched animals radial glia cells were more numerous and had more processes.. Granule cell count revealed that enriched animals had more granule cells than controls (+37% at P18 and +31% at P45). Discussion. Results show that isolation rearing reduces hippocampal cell proliferation but does not affect cell survival, while enriched rearing increases both cell proliferation and cell survival. Changes in the expression of BDNF are likely to contribute to he effects of environment on precursor cell proliferation. The reduction and increase in final number of granule neurons in isolated and enriched animals, respectively, are attributable to the effects of environment on cell proliferation and survival and not to changes in the differentiation program. As radial glia cells play a pivotal role in neuron guidance to the granule cell layer, the reduced number of radial glia cells in isolated animals and the increased number in enriched animals suggests that the size of radial glia population may change dynamically, in order to match changes in neuron production. The high PSA-NCAM expression in enriched animals may concur to favor the survival of the new neurons by facilitating their migration to the granule cell layer. Conclusions. By using a precocious rodent we could demonstrate that isolated/enriched rearing conditions, at a time window during which intense granule cell proliferation takes place, lead to a notable decrease/increase of total granule cell number. The time-course and magnitude of postnatal granule cell production in guinea pigs are more similar to the human and non-human primate condition than in rats and mice. Translation of current data to humans would imply that exposure of children to environments poor/rich of stimuli may have a notably large impact on dentate neurogenesis and, very likely, on hippocampus dependent memory functions.

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Numerous studies have shown that animals have a sense of quantity and can distinguish between relative amounts. The concepts of relative numerousness, estimation, and subitizing are well established in species as diverse as chimpanzees and salamanders. Mobile animals have practical use for an understanding of number in common situations such as predation, mating, and competition. However, the ability to identify discrete quantities has only been firmly established in humans. The purpose of this study was to test for such “absolute numerousness” judgments in three lion-tailed macaques (Macaca silenus), a non-human primate. The three macaques tested had previously been trained on a computerized matchto- sample (MTS) task using geometric shapes. In this study, they were introduced to a MTS task containing a numerical cue, which required the monkeys to match stimuli containing either one or two items for rewards. If monkeys were successful at the initial matching task, they were tested with stimuli in which the position of the items and then the surface area of the items was controlled. If the monkeys could match successfully without using these non-numerical cues, they would demonstrate the capability to make absolute numerousness judgments. None of the monkeys matched successfully using the numerical cue, so no evidence of absolute numerosity was found. Each macaque progressed through the experiment in an individualized manner, attempting a variety of strategies to obtain rewards. These included side preferences and an alternating-side strategy that were unrelated to the numerical cues in the stimuli. When it became clear that the monkeys were not matching based on a stimulus-based cue, they were tested again on matching geometric shapes. All three macaques stopped using their alternate strategies and were able to match shapes successfully, demonstrating that they were still capable of completing the matching task. The data suggest that the monkeys could not transfer this ability to the numerical stimuli. This indicates that the macaques lack a sense of exact quantity, or that they could not recognize the numerical cues in the stimuli as being relevant to the task.

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I studied the apolipoprotein (apo) B 3$\sp\prime$ variable number tandem repeat (VNTR) and did computer simulations of the stepwise mutation model to address four questions: (1) How did the apo B VNTR originate? (2) What is the mutational mechanism of repeat number change at the apo B VNTR? (3) To what extent are population and molecular level events responsible for the determination of the contemporary apo B allele frequency distribution? (4) Can VNTR allele frequency distributions be explained by a simple and conservative mutation-drift model? I used three general approaches to address these questions: (1) I characterized the apo B VNTR region in non-human primate species; (2) I constructed haplotypes of polymorphic markers flanking the apo B VNTR in a sample of individuals from Lorrain, France and studied the associations between the flanking-marker haplotypes and apo B VNTR size; (3) I did computer simulations of the one-step stepwise mutation model and compared the results to real data in terms of four allele frequency distribution characteristics.^ The results of this work have allowed me to conclude that the apo B VNTR originated after an initial duplication of a sequence which is still present as a single copy sequence in New World monkey species. I conclude that this locus did not originate by the transposition of an array of repeats from somewhere else in the genome. It is unlikely that recombination is the primary mutational mechanism. Furthermore, the clustered nature of these associations implicates a stepwise mutational mechanism. From the high frequencies of certain haplotype-allele size combinations, it is evident that population level events have also been important in the determination of the apo B VNTR allele frequency distribution. Results from computer simulations of the one-step stepwise mutation model have allowed me to conclude that bimodal and multimodal allele frequency distributions are not unexpected at loci evolving via stepwise mutation mechanisms. Short tandem repeat loci fit the stepwise mutation model best, followed by microsatellite loci. I therefore conclude that there are differences in the mutational mechanisms of VNTR loci as classed by repeat unit size. (Abstract shortened by UMI.) ^

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Dengue fever is a strictly human and non-human primate disease characterized by a high fever, thrombocytopenia, retro-orbital pain, and severe joint and muscle pain. Over 40% of the world population is at risk. Recent re-emergence of dengue outbreaks in Texas and Florida following the re-introduction of competent Aedes mosquito vectors in the United States have raised growing concerns about the potential for increased occurrences of dengue fever outbreaks throughout the southern United States. Current deficiencies in vector control, active surveillance and awareness among medical practitioners may contribute to a delay in recognizing and controlling a dengue virus outbreak. Previous studies have shown links between low-income census tracts, high population density, and dengue fever within the United States. Areas of low-income and high population density that correlate with the distribution of Aedes mosquitoes result in higher potential for outbreaks. In this retrospective ecologic study, nine maps were generated to model U.S. census tracts’ potential to sustain dengue virus transmission if the virus was introduced into the area. Variables in the model included presence of a competent vector in the county and census tract percent poverty and population density. Thirty states, 1,188 counties, and 34,705 census tracts were included in the analysis. Among counties with Aedes mosquito infestation, the census tracts were ranked high, medium, and low risk potential for sustained transmission of the virus. High risk census tracts were identified as areas having the vector, ≥20% poverty, and ≥500 persons per square mile. Census tracts with either ≥20% poverty or ≥500 persons per square mile and have the vector present are considered moderate risk. Census tracts that have the vector present but have <20% poverty and <500 persons per square mile are considered low risk. Furthermore, counties were characterized as moderate risk if 50% or more of the census tracts in that county were rated high or moderate risk, and high risk if 25% or greater were rated high risk. Extreme risk counties, which were primarily concentrated in Texas and Mississippi, were considered having 50% or greater of the census tracts ranked as high risk. Mapping of geographic areas with potential to sustain dengue virus transmission will support surveillance efforts and assist medical personnel in recognizing potential cases. ^

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En este trabajo se presenta una hipótesis evolucionista acerca del desarrollo. Se compara la infancia humana con la de los primates no humanos y se describen sus rasgos exclusivos vinculados con la extensión y transformación del mundo emocional, la interacción adulto-bebé y la formación de procesos psicológicos complejos. Se argumenta a favor del papel constitutivo de las artes temporales en cada uno de los rasgos descriptos