345 resultados para MACAQUES MACACA-FUSCATA


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The current understanding of hormonal regulation of matrix metalloproteinase-26 (MMP-26) in the primate endometrium is incomplete. The goal of this work was to clarify estrogen and progesterone regulation of MMP-26 in the endometrium of ovariectomized, hormone-treated rhesus macaques.Ovariectomized rhesus macaques (n 66) were treated with estradiol (E-2), E-2 plus progesterone, E-2 followed by progesterone alone or no hormone. Endometrium was collected from the hormone-treated animals during the early, mid- and late proliferative and secretory phases of the artificial menstrual cycle. MMP-26 expression was quantified by real-time PCR, and MMP-26 transcript and protein were localized by in situ hybridization and immunohistochemistry and correlated with estrogen receptor 1 and progesterone receptor (PGR).MMP-26 was localized to glandular epithelium and was undetectable in the endometrial stroma and vasculature. MMP-26 transcript levels were minimal in the hormone-deprived macaques and treatment with E-2 alone did not affect MMP-26 levels. Treatment with progesterone both in the presence and absence of E-2 stimulated MMP-26 expression in the early and mid-secretory phases (P 0.001). MMP-26 expression preceded decidualization of endometrial stroma. MMP-26 levels then declined to baseline in the late secretory phase (P 0.01) despite continued E-2 plus progesterone treatment. Loss of detectable MMP-26 expression in the late secretory phase was correlated with late secretory phase loss of glandular epithelial PGR.Endometrial MMP-26 expression is dependent on the presence of progesterone in the early secretory phase and then gradually becomes refractory to progesterone stimulation in the late secretory phase. In the macaque, MMP-26 is a marker of the pre-decidual, secretory endometrium. During the second half of the late secretory phase, and during decidualization, MMP-26 loses its response to progesterone concurrent with the loss of epithelial PGR. The decline in MMP-26 levels between the mid- and late secretory phases may play a role in the receptive window for embryo implantation.

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The orbitofrontal cortex (OfC) is a heterogeneous prefrontal sector selectively connected with a wide constellation of other prefrontal, limbic, sensory and premotor areas. Among the limbic cortical connections, the ones with the bippocampus and parabippocampal cortex are particularly salient. Sensory cortices connected with the OfC include areas involved in olfactory, gustatory, somatosensory, auditory and visual processing. Subcortical structures with prominent OfC connections include the amygdala, numerous thalamic nuclei, the striatum, hypothalamus, periaqueductal gray matter, and biochemically specific cell groups in the basal forebrain and brainstem. Architectonic and connectional evidence supports parcellation of the OfC. The rostrally placed isocortical sector is mainly connected with isocortical areas, including sensory areas of the auditory, somatic and visual modalities, whereas the caudal non-isocortical sector is principally connected with non-isocortical areas, and, in the sensory domain, with olfactory and gustatory areas. The connections of the isocortical and non- isocortical orbital sectors with the amygdala, thalamus, striatum, hypotbalamus and periaqueductal gray matter are also specific. The medial sector of the OfC is selectively connected with the bippocampus, posterior parabippocampal cortex, posterior cingulate and retrosplenial areas, and area prostriata, while the lateral orbitofrontal sector is the most heavily connected with sensory areas of the gustatory, somatic and visual modalities, with premotor regions, and with the amygdala.

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O presente trabalho objetivou adaptar um procedimento mecânico para o isolamento de folículos pré-antrais a partir de ovários de Cebus apella. Para isso, foi testado o efeito do intervalo de cortes seriados do tissue chopper sobre o número de folículos pré-antrais isolados a partir de ovários (n=6) de três fêmeas de C. apella, duas pré-púberes e uma adulta. Os ovários foram divididos em quatro partes iguais e fragmentados com auxílio de um tissue chopper, ajustado para a realização de secções seriadas a intervalos de 250, 500, 750 e 1000µm, respectivamente. Os folículos isolados foram contados em câmara de Neubauer e classificados em primordiais, primários e secundários. O número (média ± EP) de folículos pré-antrais isolados de 1/4 de ovário variou de 68.330+17.590, no intervalo de corte de 1.000µm, a 300.830+111.460, no intervalo de corte de 500µm, o de melhores resultados. O diâmetro médio dos folículos pré-antrais isolados variou de 11,6µm a 27, 8µm.

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Chimpanzees have been the traditional referential models for investigating human evolution and stone tool use by hominins. We enlarge this comparative scenario by describing normative use of hammer stones and anvils in two wild groups of bearded capuchin monkeys (Cebus libidinosus) over one year. We found that most of the individuals habitually use stones and anvils to crack nuts and other encased food items. Further, we found that in adults (1) males use stone tools more frequently than females, (2) males crack high resistance nuts more frequently than females, (3) efficiency at opening a food by percussive tool use varies according to the resistance of the encased food, (4) heavier individuals are more efficient at cracking high resistant nuts than smaller individuals, and (5) to crack open encased foods, both sexes select hammer stones on the basis of material and weight. These findings confirm and extend previous experimental evidence concerning tool selectivity in wild capuchin monkeys (Visalberghi et al., 2009b; Fragaszy et al., 2010b). Male capuchins use tools more frequently than females and body mass is the best predictor of efficiency, but the sexes do not differ in terms of efficiency. We argue that the contrasting pattern of sex differences in capuchins compared with chimpanzees, in which females use tools more frequently and more skillfully than males, may have arisen from the degree of sexual dimorphism in body size of the two species, which is larger in capuchins than in chimpanzees. Our findings show the importance of taking sex and body mass into account as separate variables to assess their role in tool use. (C) 2011 Elsevier Ltd. All rights reserved.

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The capuchin monkey is widespread both north and south of the Legal Amazon and in the Brazilian cerrado. Ten clinically healthy capuchin monkeys were submitted to an anatomical and radiographic study of their thoracic cavities. The radiographic evaluation allowed the description of biometric values associated with the cardiac silhouette and thoracic structures. Application of the VHS (vertebral heart size) method showed positive correlation (P<0.05) with depth of the thoracic cavity, as well as between the body length of vertebrae T 3, T 4, T 5 and T 6 and the cardiac length and width. The lung fields showed a diffuse interstitial pattern, more visible in the caudal lung lobes and a bronchial pattern in the middle and cranial lung lobes. The radiographic examination allowed preliminary inferences to be made concerning the syntopy of the thoracic structures and modifiication of the pulmonary patterns and cardiac anatomy for the capuchin monkey.

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Abstract Background Smallpox is a lethal disease that was endemic in many parts of the world until eradicated by massive immunization. Due to its lethality, there are serious concerns about its use as a bioweapon. Here we analyze publicly available microarray data to further understand survival of smallpox infected macaques, using systems biology approaches. Our goal is to improve the knowledge about the progression of this disease. Results We used KEGG pathways annotations to define groups of genes (or modules), and subsequently compared them to macaque survival times. This technique provided additional insights about the host response to this disease, such as increased expression of the cytokines and ECM receptors in the individuals with higher survival times. These results could indicate that these gene groups could influence an effective response from the host to smallpox. Conclusion Macaques with higher survival times clearly express some specific pathways previously unidentified using regular gene-by-gene approaches. Our work also shows how third party analysis of public datasets can be important to support new hypotheses to relevant biological problems.

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Prehension in an act of coordinated reaching and grasping. The reaching component is concerned with bringing the hand to object to be grasped (transport phase); the grasping component refers to the shaping of the hand according to the object features (grasping phase) (Jeannerod, 1981). Reaching and grasping involve different muscles, proximal and distal muscles respectively, and are controlled by different parietofrontal circuit (Jeannerod et al., 1995): a medial circuit, involving area of superior parietal lobule and dorsal premotor area 6 (PMd) (dorsomedial visual stream), is mainly concerned with reaching; a lateral circuit, involving the inferior parietal lobule and ventral premotor area 6 (PMv) (dorsolateral visual stream), with grasping. Area V6A is located in the caudalmost part of the superior parietal lobule, so it belongs to the dorsomedial visual stream; it contains neurons sensitive to visual stimuli (Galletti et al. 1993, 1996, 1999) as well as cells sensitive to the direction of gaze (Galletti et al. 1995) and cells showing saccade-related activity (Nakamura et al. 1999; Kutz et al. 2003). Area V6A contains also arm-reaching neurons likely involved in the control of the direction of the arm during movements towards objects in the peripersonal space (Galletti et al. 1997; Fattori et al. 2001). The present results confirm this finding and demonstrate that during the reach-to-grasp the V6A neurons are also modulated by the orientation of the wrist. Experiments were approved by the Bioethical Committee of the University of Bologna and were performed in accordance with National laws on care and use of laboratory animals and with the European Communities Council Directive of 24th November 1986 (86/609/EEC), recently revised by the Council of Europe guidelines (Appendix A of Convention ETS 123). Experiments were performed in two awake Macaca fascicularis. Each monkey was trained to sit in a primate chair with the head restrained to perform reaching and grasping arm movements in complete darkness while gazing a small fixation point. The object to be grasped was a handle that could have different orientation. We recorded neural activity from 163 neurons of the anterior parietal sulcus; 116/163 (71%) neurons were modulated by the reach-to-grasp task during the execution of the forward movements toward the target (epoch MOV), 111/163 (68%) during the pulling of the handle (epoch HOLD) and 102/163 during the execution of backward movements (epoch M2) (t_test, p ≤ 0.05). About the 45% of the tested cells turned out to be sensitive to the orientation of the handle (one way ANOVA, p ≤ 0.05). To study how the distal components of the movement, such as the hand preshaping during the reaching of the handle, could influence the neuronal discharge, we compared the neuronal activity during the reaching movements towards the same spatial location in reach-to-point and reach-to-grasp tasks. Both tasks required proximal arm movements; only the reach-to-grasp task required distal movements to orient the wrist and to shape the hand to grasp the handle. The 56% of V6A cells showed significant differences in the neural discharge (one way ANOVA, p ≤ 0.05) between the reach-to-point and the reach-to-grasp tasks during MOV, 54% during HOLD and 52% during M2. These data show that reaching and grasping are processed by the same population of neurons, providing evidence that the coordination of reaching and grasping takes place much earlier than previously thought, i.e., in the parieto-occipital cortex. The data here reported are in agreement with results of lesions to the medial posterior parietal cortex in both monkeys and humans, and with recent imaging data in humans, all of them indicating a functional coupling in the control of reaching and grasping by the medial parietofrontal circuit.

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Many psychophysical studies suggest that target depth and direction during reaches are processed independently, but the neurophysiological support to this view is so far limited. Here, we investigated the representation of reach depth and direction by single neurons in an area of the medial posterior parietal cortex (V6A). Single-unit activity was recorded from V6A in two Macaca fascicularis monkeys performing a fixation-to-reach task to targets at different depths and directions. We found that in a substantial percentage of V6A neurons depth and direction signals jointly influenced fixation, planning and arm movement-related activity in 3D space. While target depth and direction were equally encoded during fixation, depth tuning became stronger during arm movement planning, execution and target holding. The spatial tuning of fixation activity was often maintained across epochs, and this occurred more frequently in depth. These findings support for the first time the existence of a common neural substrate for the encoding of target depth and direction during reaching movements in the posterior parietal cortex. Present results also highlight the presence in V6A of several types of cells that process independently or jointly eye position and arm movement planning and execution signals in order to control reaches in 3D space. It is possible that depth and direction influence also the metrics of the reach action and that this effect on the reach kinematic variables can account for the spatial tuning we found in V6A neural activity. For this reason, we recorded and analyzed behavioral data when one monkey performed reaching movements in 3-D space. We evaluated how the target spatial position, in particular target depth and target direction, affected the kinematic parameters and trajectories describing the motor action properties.

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In dieser Arbeit wurden Zellkulturen primärer Hepatozyten von Ratte und Mensch hinsichtlich ihrer Eignung untersucht Speziesunterschiede der toxischen Wirkung und des Metabolismus von Substanzen darzustellen und inwieweit die in vitro-Ergebnisse in vivo vergleichbar bzw. übertragbar sind. Des Weiteren wurde ein Zellkulturmodell entwickelt, das eine Kultivierung von primären Hepatozyten aus Ratte, Mensch und Maus über einen Zeitraum von mindestens einer bis zwei Wochen erlaubt.rnrnDie Zellkulturen primärer Hepatozyten von Ratte und Mensch zeigten deutliche Unterschiede in der substanzinduzierten Veränderung der Genexpression nach Behandlung mit den, vor allem für den Menschen, lebertoxischen Substanzen Diclofenac und Troglitazon. Diese Unterschiede traten hauptsächlich in der Induktion fremdstoffmetabolisierender Enzyme sowie deren transkriptionsregulierenden Kernrezeptoren in den humanen Hepatozyten auf. Ebenso war eine verstärkte Stressantwort zu beobachten.rnDeutliche Speziesunterschiede konnten ebenso in der Wirkung der Arzneimittelentwicklungssubstanz EMD 392949 auf die Aktivität bzw. Genexpression von Cytochrom P450 Enzymen sowie deren Regulatoren nachgewiesen werden. Des Weiteren konnte hier eine sehr gute Übereinstimmung der Ergebnisse aus den Zellkulturen primärer Ratten- bzw. Humanhepatozyten mit jenen aus in vivo-Experimenten mit Ratten bzw. Affen (Macaca fascicularis) beobachtet werden, was die Aussagekraft der Primärkulturen verdeutlichte.rnDie große Übereinstimmung zwischen Enzymaktivität und Genexpression in der Induktion fremdstoffmetabolisierender Enzyme konnte durch die Behandlung mit einer Reihe speziesspezifischer Induktoren in Zellkulturen primärer Ratten- bzw. Humanhepatozyten bestätigt werden; vor allem nach dem von der amerikanischen Arzneimittelzulassungsbehörde (FDA, Food and Drug Administartion) vorgeschlagenen Bewertungsschema zur Untersuchung der CYP-Induktion.rnrnDie Lebensdauer sowie der Differenzierungsgrad von primären Hepatozyten in Kultur sind stark abhängig von den Zellkulturbedingungen. Durch diese Arbeit konnte gezeigt werden, dass spezifische Eigenschaften von Rattenleberzellen durch Kultivierung in einem Sandwich aus zwei hydratisierten Collagengelschichten und unter serumfreien Bedingungen für einen Zeitraum von mindestens zwei Wochen aufrechterhalten werden können. Dieses Kulturmodel konnte auf Primärhepatozyten von Mensch und Maus übertragen werden und erweitert die möglichen Anwendungen hin zu einer Behandlung über einen längeren Zeitraum und der Untersuchung von subchronischen Effekten.rn

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To enhance understanding of the metabolic indicators of type 2 diabetes mellitus (T2DM) disease pathogenesis and progression, the urinary metabolomes of well characterized rhesus macaques (normal or spontaneously and naturally diabetic) were examined. High-resolution ultra-performance liquid chromatography coupled with the accurate mass determination of time-of-flight mass spectrometry was used to analyze spot urine samples from normal (n = 10) and T2DM (n = 11) male monkeys. The machine-learning algorithm random forests classified urine samples as either from normal or T2DM monkeys. The metabolites important for developing the classifier were further examined for their biological significance. Random forests models had a misclassification error of less than 5%. Metabolites were identified based on accurate masses (<10 ppm) and confirmed by tandem mass spectrometry of authentic compounds. Urinary compounds significantly increased (p < 0.05) in the T2DM when compared with the normal group included glycine betaine (9-fold), citric acid (2.8-fold), kynurenic acid (1.8-fold), glucose (68-fold), and pipecolic acid (6.5-fold). When compared with the conventional definition of T2DM, the metabolites were also useful in defining the T2DM condition, and the urinary elevations in glycine betaine and pipecolic acid (as well as proline) indicated defective re-absorption in the kidney proximal tubules by SLC6A20, a Na(+)-dependent transporter. The mRNA levels of SLC6A20 were significantly reduced in the kidneys of monkeys with T2DM. These observations were validated in the db/db mouse model of T2DM. This study provides convincing evidence of the power of metabolomics for identifying functional changes at many levels in the omics pipeline.

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High levels of HIV-1 replication during the chronic phase of infection usually correlate with rapid progression to severe immunodeficiency. However, a minority of highly viremic individuals remains asymptomatic and maintains high CD4⁺ T cell counts. This tolerant profile is poorly understood and reminiscent of the widely studied nonprogressive disease model of SIV infection in natural hosts. Here, we identify transcriptome differences between rapid progressors (RPs) and viremic nonprogressors (VNPs) and highlight several genes relevant for the understanding of HIV-1-induced immunosuppression. RPs were characterized by a specific transcriptome profile of CD4⁺ and CD8⁺ T cells similar to that observed in pathogenic SIV-infected rhesus macaques. In contrast, VNPs exhibited lower expression of interferon-stimulated genes and shared a common gene regulation profile with nonpathogenic SIV-infected sooty mangabeys. A short list of genes associated with VNP, including CASP1, CD38, LAG3, TNFSF13B, SOCS1, and EEF1D, showed significant correlation with time to disease progression when evaluated in an independent set of CD4⁺ T cell expression data. This work characterizes 2 minimally studied clinical patterns of progression to AIDS, whose analysis may inform our understanding of HIV pathogenesis.

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BrainMaps.org is an interactive high-resolution digital brain atlas and virtual microscope that is based on over 20 million megapixels of scanned images of serial sections of both primate and non-primate brains and that is integrated with a high-speed database for querying and retrieving data about brain structure and function over the internet. Complete brain datasets for various species, including Homo sapiens, Macaca mulatta, Chlorocebus aethiops, Felis catus, Mus musculus, Rattus norvegicus, and Tyto alba, are accessible online. The methods and tools we describe are useful for both research and teaching, and can be replicated by labs seeking to increase accessibility and sharing of neuroanatomical data. These tools offer the possibility of visualizing and exploring completely digitized sections of brains at a sub-neuronal level, and can facilitate large-scale connectional tracing, histochemical and stereological analyses.

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BACKGROUND: A key aspect of representations for object recognition and scene analysis in the ventral visual stream is the spatial frame of reference, be it a viewer-centered, object-centered, or scene-based coordinate system. Coordinate transforms from retinocentric space to other reference frames involve combining neural visual responses with extraretinal postural information. METHODOLOGY/PRINCIPAL FINDINGS: We examined whether such spatial information is available to anterior inferotemporal (AIT) neurons in the macaque monkey by measuring the effect of eye position on responses to a set of simple 2D shapes. We report, for the first time, a significant eye position effect in over 40% of recorded neurons with small gaze angle shifts from central fixation. Although eye position modulates responses, it does not change shape selectivity. CONCLUSIONS/SIGNIFICANCE: These data demonstrate that spatial information is available in AIT for the representation of objects and scenes within a non-retinocentric frame of reference. More generally, the availability of spatial information in AIT calls into questions the classic dichotomy in visual processing that associates object shape processing with ventral structures such as AIT but places spatial processing in a separate anatomical stream projecting to dorsal structures.

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The predominant route of human immunodeficiency virus type 1 (HIV-1) transmission is infection across the vaginal mucosa. Epithelial cells, which form the primary barrier of protection against pathogens, are the first cell type at these mucosal tissues to encounter the virus but their role in HIV infection has not been clearly elucidated. Although mucosal epithelial cells express only low levels of the receptors required for successful HIV infection, productive infection does occur at these sites. The present work provides evidence to show that HIV exposure, without the need for productive infection, induces human cervical epithelial cells to produce Thymic Stromal Lymphopoietin (TSLP), an IL7-like cytokine, which potently activated human myeloid dendritic cells (mDC) to cause the homeostatic proliferation of autologous CD4+ T cells that serve as targets for HIV infection. Rhesus macaques inoculated with simian immunodeficiency virus (SIV) or with the simian-human immunodeficiency virus (SHIV) by the vaginal, oral or rectal route exhibited dramatic increases in: TSLP expression, DC and CD4+ T cell numbers, and viral replication, in the vaginal, oral, and rectal tissues, respectively within the first 2 weeks after virus exposure. Evidence obtained showed that HIV-mediated TSLP production by cervical cells is dependent upon the expression of the cell surface salivary agglutinin (SAG) protein gp340. Epithelial cells expressing gp340 exhibited HIV endocytosis and TSLP expression and genetic knockdown of gp340 or use of a gp340-blocking antibody inhibited TSLP expression by HIV. On the other hand, gp340-null epithelial cells failed to endocytose HIV and produce TSLP, but transfection of gp340 resulted in HIV-induced TSLP expression. Finally, HIV-induced TSLP expression was found to be mediated by TLR7/8 signaling and NF-kB activity because silencing these pathways or use of specific inhibitors abrogated TSLP expression in gp340-postive but not in gp340-null epithelial cells. Overall these studies identify TSLP as a key player in the acute phase of HIV-1 infection in permitting HIV to successfully maneuver the hostile vaginal mucosal microenvironment by creating a conducive environment for sustaining the small amount of virus that initially crosses the mucosal barrier allowing it to successfully cause infection and spread to distal compartments of the body