788 resultados para iris recognition
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The innate and adaptive immune responses of dendritic cells (DCs) to enteroinvasive Escherichia coli (EIEC) infection were compared with DC responses to Shigella flexneri infection. EIEC triggered DCs to produce interleukin (IL)-10, IL-12 and tumour necrosis factor (TNF)-alpha, whereas S. flexneri induced only the production of TNF-alpha. Unlike S. flexneri, EIEC strongly increased the expression of toll like receptor (TLR)-4 and TLR-5 in DCs and diminished the expression of co-stimulatory molecules that may cooperate to inhibit CD4(+) T-lymphocyte proliferation. The inflammation elicited by EIEC seems to be related to innate immunity both because of the aforementioned results and because only EIEC were able to stimulate DC transmigration across polarised Caco-2 cell monolayers, a mechanism likely to be associated with the secretion of CC chemokine ligands (CCL) 20 and TNF-alpha. Understanding intestinal DC biology is critical to unravelling the infection strategies of EIEC and may aid in the design of treatments for infectious diseases.
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Background: Despite the fact that public speaking is a common academic activity and that social phobia has been associated with lower educational achievement and impaired academic performance, little research has examined the prevalence of social phobia in college students. The aim of this study was to evaluate the prevalence of social phobia in a large sample of Brazilian college students and to examine the academic impact of this disorder. Methods: The Social Phobia Inventory (SPIN) and the MINI-SPIN, used as the indicator of social phobia in the screening phase, were applied to 2319 randomly selected students from two Brazilian universities. For the second phase (diagnostic confirmation), four psychiatrists and one clinical psychologist administered the SCID-IV to subjects with MINI-SPIN scores of 6 or higher. Results: The prevalence of social phobia among the university students was 11.6%. Women with social phobia had significantly lower grades than those without the disorder. Fear of public speaking was the most common social fear. Only two of the 237 students with social phobia (0.8%) had previously received a diagnosis of social phobia and were under treatment. Limitations: Social phobia comorbidities were not evaluated in this study. The methods of assessment employed by the universities (written exams) may mask the presence of social phobia. This was not a population-based study, and thus the results are not generalizable to the entire population with social phobia. Conclusion: Preventive strategies are recommended to reduce the under-recognition and the adverse impact of social phobia on academic performance and overall quality of life of university students. (C) 2011 Elsevier B.V. All rights reserved.
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To describe a new method for iris fixation of intraocular lens in the absence of capsular support during penetrating keratoplasty. Its a new technique of iris fixation of intraocular lens without capsular support during penetrating keratoplasty. This technique is used in cases with a healthy iris and partial or total absence of capsular support during penetrating keratoplasty. Tied Out Open Sky is a technique easy to perform for iris fixation of intraocular lens during penetrating keratoplasty. The big advantage is being able to tie off the intraocular lens off the eye and fasten it securely.
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Objectives: To evaluate the colour stability of paints used for ocular prosthesis iris painting submitted for accelerated artificial ageing (AAA). Materials and methods: Forty specimens of acrylic resin for sclera (16 x 2 mm) were made and separated into eight groups (n = 10) according to the type of paint (gouache, GP; oil, OP; acrylic AP; and composite resin for characterisation, CR) and the colours used (blue/brown). After drying (72 h), a new layer of colourless acrylic resin was applied and the initial colour readout was performed (Spectrophotometer PCB 6807). New colour readouts were performed after AAA, and Delta E was calculated. Results: Statistical analysis (two-way ANOVA-Bonferroni, p < 0.05) demonstrated that the brown colour showed lower Delta E means in comparison with the blue colour, with statistically significant difference for AP only. Blue colour showed no statistically significant difference with regard to the type of paint used. Brown AP showed lower Delta E than the other groups, with significant difference for OP and GP. GP showed greater alteration in Delta E for the brown colour, being statistically similar only to OP. Conclusions: Only the AP group for brown pigment shows clinically acceptable values for colour stability after AAA.
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Introduction: Impairments in facial emotion recognition (PER) have been reported in bipolar disorder (BD) during all mood states. FER has been the focus of functional magnetic resonance imaging studies evaluating differential activation of limbic regions. Recently, the alpha 1-C subunit of the L-type voltage-gated calcium channel (CACNA1C) gene has been described as a risk gene for BD and its Met allele found to increase CACNA1C mRNA expression. In healthy controls, the CACNA1C risk (Met) allele has been reported to increase limbic system activation during emotional stimuli and also to impact on cognitive function. The aim of this study was to investigate the impact of CACNA1C genotype on FER scores and limbic system morphology in subjects with BD and healthy controls. Material and methods: Thirty-nine euthymic BD I subjects and 40 healthy controls were submitted to a PER recognition test battery and genotyped for CACNA1C. Subjects were also examined with a 3D 3-Tesla structural imaging protocol. Results: The CACNA1C risk allele for BD was associated to FER impairment in BD, while in controls nothing was observed. The CACNA1C genotype did not impact on amygdala or hippocampus volume neither in BD nor controls. Limitations: Sample size. Conclusion: The present findings suggest that a polymorphism in calcium channels interferes FER phenotype exclusively in BD and doesn't interfere on limbic structures morphology. (C) 2012 Elsevier B.V. All rights reserved.
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Recent research has shown that entrance guards of the stingless bee Tetragonisca angustula make less errors in distinguishing nestmates from non-nestmates than all other bee species studied to date, but how they achieve this is unknown. We performed four experiments to investigate nestmate recognition by entrance guards in T. angustula. We first investigated the effect of colony odours on acceptance. Nestmates that acquired odour from non-nestmate workers were 63% more likely to be rejected while the acceptance rate of non-nestmates treated with nestmate odour increased by only 7%. We further hypothesised that guards standing on the wax entrance tube might use the tube as an odour referent. However, our findings showed that there was no difference in the acceptance of non-nestmates by guards standing on their own colony's entrance tube versus the non-nestmate's entrance tube. Moreover, treatment of bees with nestmate and non-nestmate resin or wax had a negative effect on acceptance rates of up to 65%, regardless of the origin of the wax or resin. The role of resin as a source of recognition cues was further investigated by unidirectionally transferring resin stores between colonies. Acceptance rates of nestmates declined by 37% for hives that donated resin, contrasting with resin donor hives where acceptance of non-nestmates increased by 21%. Overall, our results confirm the accuracy of nestmate recognition in T. angustula and reject the hypothesis that this high level of accuracy is due to the use of the wax entrance tubes as a referent for colony odour. Our findings also suggest that odours directly acquired from resin serve no primary function as nestmate recognition cues. The lack of consistency among colonies plus the complex results of the third and fourth experiments highlight the need for further research on the role of nest materials and cuticular profiles in understanding nestmate recognition in T. angustula.
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The spleen plays a crucial role in the development of immunity to malaria, but the role of pattern recognition receptors (PRRs) in splenic effector cells during malaria infection is poorly understood. In the present study, we analysed the expression of selected PRRs in splenic effector cells from BALB/c mice infected with the lethal and non-lethal Plasmodium yoelii strains 17XL and 17X, respectively, and the non-lethal Plasmodium chabaudi chabaudi AS strain. The results of these experiments showed fewer significant changes in the expression of PRRs in AS-infected mice than in 17X and 17XL-infected mice. Mannose receptor C type 2 (MRC2) expression increased with parasitemia, whereas Toll-like receptors and sialoadhesin (Sn) decreased in mice infected with P. chabaudi AS. In contrast, MRC type 1 (MRC1), MRC2 and EGF-like module containing mucin-like hormone receptor-like sequence 1 (F4/80) expression decreased with parasitemia in mice infected with 17X, whereas MRC1 an MRC2 increased and F4/80 decreased in mice infected with 17XL. Furthermore, macrophage receptor with collagenous structure and CD68 declined rapidly after initial parasitemia. SIGNR1 and Sn expression demonstrated minor variations in the spleens of mice infected with either strain. Notably, macrophage scavenger receptor (Msr1) and dendritic cell-associated C-type lectin 2 expression increased at both the transcript and protein levels in 17XL-infected mice with 50% parasitemia. Furthermore, the increased lethality of 17X infection in Msr1 -/- mice demonstrated a protective role for Msr1. Our results suggest a dual role for these receptors in parasite clearance and protection in 17X infection and lethality in 17XL infection.
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Toxosplasma gondii is the model parasite of the phylum Apicomplexa, which contains numerous obligate intracellular parasites of medical and veterinary importance, including Eimeria, Sarcocystis, Cryptosporidium, Cyclospora, and Plasmodium species. Members of this phylum actively enter host cells by a multistep process with the help of microneme protein (MIC) complexes that play important roles in motility, host cell attachment, moving junction formation, and invasion. T. gondii (Tg)MIC1-4-6 complex is the most extensively investigated microneme complex, which contributes to host cell recognition and attachment via the action of TgMIC1, a sialic acid-binding adhesin. Here, we report the structure of TgMIC4 and reveal its carbohydrate-binding specificity to a variety of galactose-containing carbohydrate ligands. The lectin is composed of six apple domains in which the fifth domain displays a potent galactose-binding activity, and which is cleaved from the complex during parasite invasion. We propose that galactose recognition by TgMIC4 may compromise host protection from galectin-mediated activation of the host immune system.
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Although a large amount of data have been published in past years on the taxonomic status of the Anastrepha fraterculus (Wiedemann) species complex, there is still a need to know how many species this complex comprises, the distribution of each one, and their distinguishing features. In this study, we assessed the morphometric variability of 32 populations from the A. fraterculus complex, located in major biogeographical areas from the Neotropics. Multivariate techniques for analysis were applied to the measurements of 21 variables referring to the mesonotum, aculeus, and wing. For the first time, our results identified the presence of seven distinct morphotypes within this species complex. According to the biogeographical areas, populations occurring in the Mesoamerican dominion (Mexico, Guatemala, and Panama) were clustered within a single natural entity labeled as the "Mexican" morphotype; whereas in the northwestern South American dominion, samples fell into three distinct groups: the "Venezuelan" morphotype with a single population from the Caribbean lowlands of Venezuela, the "Andean" morphotype from the highlands of Venezuela and Colombia, and the third group or "Peruvian" morphotype comprised the samples from the Pacific coastal lowlands of Ecuador and Peru. Three additional groups were identified from the Chacoan and Paranaense sub-regions: the morphotype "Brazilian-1" was recognized as including the Argentinean samples with most pertaining to Brazil, and widely distributed in these biogeographical areas; the morphotype "Brazilian-2" was recognized as including two samples from the state of Sao Paulo (Ilha-Bela and Sao Sebastiao); whereas the morphotype "Brazilian-3" included a single population from Botucatu (state of Sao Paulo). Based on data published by previous authors showing genetic and karyotypic differentiation, as well as reproductive isolation, we have concluded that such morphotypes indeed represent natural groups and distinct taxonomic entities.
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NIH, ICGEB, FAPESP, CNPq
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Cognitive dysfunction is found in patients with brain tumors and there is a need to determine whether it can be replicated in an experimental model. In the present study, the object recognition (OR) paradigm was used to investigate cognitive performance in nude mice, which represent one of the most important animal models available to study human tumors in vivo. Mice with orthotopic xenografts of the human U87MG glioblastoma cell line were trained at 9, 14, and 18days (D9, D14, and D18, respectively) after implantation of 5×10(5) cells. At D9, the mice showed normal behavior when tested 90min or 24h after training and compared to control nude mice. Animals at D14 were still able to discriminate between familiar and novel objects, but exhibited a lower performance than animals at D9. Total impairment in the OR memory was observed when animals were evaluated on D18. These alterations were detected earlier than any other clinical symptoms, which were observed only 22-24days after tumor implantation. There was a significant correlation between the discrimination index (d2) and time after tumor implantation as well as between d2 and tumor volume. These data indicate that the OR task is a robust test to identify early behavior alterations caused by glioblastoma in nude mice. In addition, these results suggest that OR task can be a reliable tool to test the efficacy of new therapies against these tumors.
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[EN]Gender recognition has achieved impressive results based on the face appearance in controlled datasets. Its application in the wild and large datasets is still a challenging task for researchers. In this paper, we make use of classical techniques to analyze their performance in controlled and uncontrolled condition respectively with the LFW and MORPH datasets. For both sets the benchmarking protocol follows the 5-fold cross-validation proposed by the BEFIT challenge.
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One of the problems in the analysis of nucleus-nucleus collisions is to get information on the value of the impact parameter b. This work consists in the application of pattern recognition techniques aimed at associating values of b to groups of events. To this end, a support vec- tor machine (SVM) classifier is adopted to analyze multifragmentation reactions. This method allows to backtracing the values of b through a particular multidimensional analysis. The SVM classification con- sists of two main phase. In the first one, known as training phase, the classifier learns to discriminate the events that are generated by two different model:Classical Molecular Dynamics (CMD) and Heavy- Ion Phase-Space Exploration (HIPSE) for the reaction: 58Ni +48 Ca at 25 AMeV. To check the classification of events in the second one, known as test phase, what has been learned is tested on new events generated by the same models. These new results have been com- pared to the ones obtained through others techniques of backtracing the impact parameter. Our tests show that, following this approach, the central collisions and peripheral collisions, for the CMD events, are always better classified with respect to the classification by the others techniques of backtracing. We have finally performed the SVM classification on the experimental data measured by NUCL-EX col- laboration with CHIMERA apparatus for the previous reaction.