996 resultados para CHALLENGE TEST


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Motor impairments of Parkinson`s disease (PD) appear only after the loss of more than 70% of the DAergic neurons of the substantia nigra pars compacta (SNc). An earlier phase of this disease can be modeled in rats that received a unilateral infusion of the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrindine (MPTP) into the SNc. Though these animals do not present gross motor impairments, they rotate towards the lesioned side when challenged with DAergic drugs, like amphetamine and apomorphine. The present study aimed to test whether these effects occur because the drugs disrupt compensatory mechanisms that keep extracellular levels of dopamine in the striatum (DA(E)) unchanged. This hypothesis was tested by an in vivo microdialysis study in awake rats with two probes implanted in the right and left striatum. Undrugged rats did not present turning behaviour and their basal DA(E) did not differ between the lesioned and sham-lesioned sides. However, after apomorphine treatment, DA(E) decreased in both sides, but to a larger extent in the lesioned side at the time the animals started ipsiversive turning behaviour. After amphetamine challenge, DA(E) increased in both sides, becoming significantly higher in the non-lesioned side at the time the animals started ipsiversive turning behaviour. These results are in agreement with the hypothesis that absence of gross motor impairments in this rat model of early phase PD depends on maintenance of extracellular DA by mechanisms that may be disrupted by events demanding its alteration to higher or lower levels. (C) 2010 Elsevier B.V. All rights reserved.

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The effect of intraseptal injections of lidocaine before a first or a second session in the elevated plus-maze, in a test-retest paradigm, was investigated. In addition to gross session analyses, a minute-by-minute analysis of the sessions was used to evaluate both anxiety and memory. Lidocaine injections before the test session produced increases in the frequency of entries, time spent and distance run in the open arms without affecting activity occurring in the closed arms. During the retest session, saline- and lidocaine-treated rats exhibited increased indices of anxiety and lidocaine-treated rats exhibited decreased closed-arm entries. The minute-by-minute analysis showed a faster decrease in anxiety-related behaviors during the test session by saline- than by lidocaine-treated rats and a significant decrease in closed-arm exploration by saline-treated rats, but not by lidocaine-treated ones. Lidocaine injection before the retest session produced increases in the frequency of entries, time spent and distance run in the open arms in the second session when compared with saline-treated rats. Minute-by-minute analysis showed an increase in the time spent in the open arms by lidocaine animals at the beginning of the retest session in comparison to saline animals and a significant decrease in closed-arm exploration by both groups. These results suggest that inactivation of the medial septum by lidocaine affects the expression of unconditioned and conditioned forms of anxiety in the elevated plus-maze and, in a lesser way, the acquisition and retention of spatial information. (C) 2010 Elsevier B.V. All rights reserved.

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The inferior colliculus (IC) together with the dorsal periaqueductal gray (dPAG), the amygdala and the medial hypothalamus make part of the brain aversion system, which has mainly been related to the organization of unconditioned fear. However, the involvement of the IC and dPAG in the conditioned fear is still unclear. It is certain that GABA has a regulatory role on the aversive states generated and elaborated in these midbrain structures. In this study, we evaluated the effects of injections of the GABA-A receptor agonist muscimol (1.0 and 2.0 nmol/0.2 mu L) into the IC or dPAG on the freezing and fear-potentiated startle (FPS) responses of rats submitted to a context fear conditioning. Intra-IC injections of muscimol did not cause any significant effect on the FPS or conditioned freezing but enhanced the startle reflex in non-conditioned animals. In contrast, intra-dPAG injections of muscimol caused significant reduction in FPS and conditioned freezing without changing the startle reflex in non-conditioned animals. Thus, intra-dPAG injections of muscimol produced the expected inhibitory effects on the anxiety-related responses, the FPS and the freezing whereas these injections into the IC produced quite opposite effects suggesting that descending inhibitory pathways from the IC, probably mediated by GABA-A mechanisms, exert a regulatory role on the lower brainstem circuits responsible for the startle reflex. (C) 2008 Elsevier Inc. All rights reserved.

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Although several reports have demonstrated physiological and behavioral changes in adult rats due to neonatal immune challenges, little is known about their effects in adolescence. Since neonatal exposure to lipopolysaccharide (LPS) alters the neural substrates involved in cognitive disorders, we tested the hypothesis that it may also alter the response to novel environments in adolescent rats. At 3 and 5 days of age, male Wistar rats received intraperitoneal injections of either vehicle solution or E. coli LPS (0.05 mg/kg) or were left undisturbed. In the mid-adolescent period, between 40 and 46 days of age, the rats were exposed to the following behavioral tests: elevated plus-maze, open-field, novel-object exploration task, hole-board and the modified Porsolt forced swim test. The results showed that, in comparison with control animals, LPS-treated rats exhibited (1) less anxiety-related behaviors and enhanced patterns of locomotion and rearing in the plus-maze and the open-field tests, (2) high levels of exploration of both objects in the novel-object task and of corner and central holes in hole-board test, and (3) more time spent diving, an active behavior in the forced swim test. The present findings suggest that neonatal LPS exposure has long-lasting effects on the behavior profile adolescent rats exhibit in response to novelty. This behavioral pattern, characterized by heightened exploratory activity in novel environments, also suggests that early immune stimulation may contribute to the development of impulsive behavior in adolescent rats. (C) 2010 Elsevier B.V. All rights reserved.

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A central tenet of life-history theory is the presence of a trade-off between the size and number of offspring that a female can produce for a given clutch. A crucial assumption of this trade-off is that larger offspring perform better than smaller offspring. Despite the importance of this assumption empirical, field-based tests are rare, especially for marine organisms. We tested this assumption for the marine invertebrate, Diplosoma listerianum, a colonial ascidian that commonly occurs in temperate marine communities. Colonies that came from larger larvae had larger feeding structures than colonies that came from smaller larvae. Colonies that came from larger larvae also had higher survival and growth after 2 weeks in the field than colonies that came from smaller larvae. However, after 3 weeks in the field the colonies began to fragment and we could not detect an effect of larval size. We suggest that offspring size can have strong effects on the initial recruitment of D. listerianum but because of the tendency of this species to fragment, offspring size effects are less persistent in this species than in others.

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The object of this study is to assess informative possibilities of some technical indicators of the Test of Photos of Professions (BBT - Berufsbilder test), a projective method to clarify professional inclination, proposed by Martin Achtnich. This psychological evaluation technique is composed of 96 photos of professionals, performing various types of activities. The test subject classifies the photos into three groups: positive (agreeable), negative (disagreeable) and indifferent (neutral). Among those chosen positively, five preferences are chosen and a story is developed that includes them, an activity that is requested two times during the Vocational Guidance process: in the beginning (or middle) and at the end of the intervention. In this study, 160 stories were created by 80 youths, between 15 and 20 years of age, in public and private schools in a mid-sized Brazilian city. The stories were compared in three analytical categories: protagonist, professional conflict and resolution. The results were submitted to Wilcoxon nonparametric statistical analysis (p < .05), significant and relevant indicators of resolution being found in the process of occupational choice. This technical resource was shown, from this empirical evidence, to be promising for use in evaluation of intervention processes of Vocational Guidance.

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Tuberculosis, a polymorphic disease, is a diagnostic challenge, particularly when arises concomitantly to an autoimmune disease such as rheumatoid arthritis (RA). Herein, the authors describe a 33-year-old woman with nodular RA who was being treated with methotrexate, sulfasalazine and corticosteroids and presented with subcutaneous nodules simultaneously with aseptic meningitis. Mycobacterium tuberculosis was identified in cultures from a biopsy of an axillary nodule. The patient also developed polyuria and polydipsia with normal glycemia; antidiuretic hormone (ADH) treatment before and after a 3% saline infusion test was performed and diabetes insipidus was diagnosed. An encephalic MRI showed sellar and suprasellar masses, suggesting central diabetes insipidus (CDI). The patient received standard tuberculosis (TB) treatment for 6 months and also DDAVP (desmopressin acetate) during this period. Control of CDI was observed. A pre-surgical magnetic resonance imaging (MRI) showed no pituitary mass. It is known that intrasellar tuberculoma occurs in only 1% of TB patients. TB should be considered in the differential diagnosis of CDI, especially in immunosupressed patients and in countries where this infection is a serious public health problem.

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Two longitudinal experiments involving Angora goats challenged with either bovine or ovine strains of Mycobacterium avium subspecies paratuberculosis (Map) have been conducted over a period of 54 and 35 months, respectively. Blood samples for the interferon-gamma (IFN-gamma) test and the absorbed ELISA and faecal samples for bacteriological culture were taken pre-challenge and monthly post-challenge. Persistent shedding, IFN-gamma production, seroconversion and clinical disease occurred earlier with the bovine Map gut mucosal tissue challenge inoculum than with cultured bacteria. The IFN-gamma responses of the gut mucosal tissue and bacterial challenge groups were substantially and consistently higher than those of the control group. The in vivo and cultured cattle strains were much more pathogenic for goats than the sheep strains with persistent faecal shedding, seroconversion and clinical disease occurring in the majority of bovine Map challenged goats. With the ovine Map, 3 goats developed persistent antibody responses but only one of these goats developed persistent faecal shedding and clinical disease. However, there was no significant difference between the IFN-gamma responses of the tissue challenged, bacterial challenged and control groups. Compared with sheep, the ELISA appeared to have higher sensitivity and the IFN-gamma test lower specificity. (C) 2005 Elsevier B.V. All rights reserved.

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Introduction: Number 3 cleft or oral-nasal-ocular cleft is a well-known entity that was described by Morian over a century ago. This malformation is a paranasal-medial orbitomaxillary cleft running across the lacrimal segment of the lower eyelid and over the lacrimal groove. The Tessier number 3 naso-ocular cleft represents one of the most difficult and challenging malformations to correct for the reconstructive surgeon. We have conducted a retrospective analysis of our series consisting of 21 cases. Objective: The objective was to review the functional outcome and aesthetic results of the different techniques applied for each case. Materials and Methods: From 1997 to 2007, 21 patients with a Tessier number 3 cleft were treated in our craniofacial units. The clinical findings, tomographic studies, and surgical procedures were reviewed and analyzed. We have discussed our protocol of the treatment. Results: We have treated facial malformation in 2 craniofacial centers. Fourteen patients were evaluated in the first year of their life, with an average age at presentation of 3 years. Twelve patients were female, and 9 were male; 6 patients had amniotic bands in limbs, 5 patients had an association with Tessier number 11 cleft, 3 patients with number 9 cleft, and 1 with number 7 cleft. Related to cleft lip, 10 patients had bilateral cleft lip, and 8 patients had unilateral cleft lip. Three patients did not have any involvement of the upper lip. The alar base was deviated upward in 19 patients, 11 cases had severe anatomic alteration with the lateral border of the ala above the medial canthus, and 8 cases had a mild dislocation. Nine cases of lacrimal duct obstruction and 8 cases of lacrimal duct extrophy were identified. Twelve patients had a lower eyelid coloboma of varying grades, and there were 2 cases of microblepharia. Aiming the soft tissue reconstruction, eyelid, nose, and upper lip were evaluated regarding their position, absence of tissue, and position of medial canthus and ala. Twelve of our patients underwent correction in the same moment, their medial canthus rotated upward and the ala downward, using the contralateral side as the reference. The lip was treated using a Millard-like technique. Neo-conjunctivorhinostomy was performed in the same moment in 2 patients or later in 1 case. Four patients had plagiocephaly due to the cranial involvement, and they were submitted to cranioplasty. Three had neurosurgical approach and advancement of the frontal bandeau. One adult patient received an acrylic plate to reshape the frontal area. Conclusions: Tessier number 3 cleft is one of the most difficult and challenging malformations to correct for the reconstructive surgeon. Besides the difficulties of its treatment, patients with Tessier number 3 cleft may achieve good results when the team has good skills.

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We identify a test of quantum mechanics versus macroscopic local realism in the form of stochastic electrodynamics. The test uses the steady-state triple quadrature correlations of a parametric oscillator below threshold.

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BACKGROUND: Persons with human immunodeficiency virus (HIV) risk behaviors are excluded from donation to reduce the risk of transfusion-transmitted infection. Persons donating to be tested for HIV may therefore deny risk behaviors. STUDY DESIGN AND METHODS: A random sample of donors completed a survey on motivations, knowledge, and attitudes on the screening process. Donors were considered test seekers if they agreed with two statements ""I think that blood donation is a good, fast, and anonymous way to get my blood tested"" and ""I donate to get my test results."" This study was conducted from June to November 2006 at the largest blood bank in Sao Paulo, Brazil. RESULTS: Of 3061 participants, 208 (7%) were test seekers. They tended to be male and had a lower educational level. They were more likely to have incorrect knowledge about blood safety (e.g., not knowing that a unit can test antibody negative and still transmit infection, 60% vs. 42%, p = 0.02), express dissatisfaction with screening questions (e.g., feeling that important questions were not asked, 14% vs. 5%, p < 0.01), and concur that donors do not answer questions truthfully (e.g., donors have more sexual partners than they admit, 29% vs. 18%, p < 0.01). Test seekers were more likely to believe that it is acceptable to donate blood to get tested for HIV (41% vs. 10%, p < 0.01). CONCLUSIONS: Test-seeking motivation, coupled with low knowledge of window period risk, is counter to improving blood safety and to donor prevention needs. Donor education needs to be improved along with availability of appropriate HIV counseling and testing.

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P>Background: Many patients with common variable immunodeficiency (CVID) have a clinical history suggestive of allergic respiratory disease. However, in such individuals, the prevalence of asthma and the role of atopy have not been well established. The objective of this study was to evaluate pulmonary function and identify asthma in patients with CVID. We also investigated the role of IgE as a trigger of asthma in these patients. Methods: Sixty-two patients diagnosed with CVID underwent spirometry, as well as skin prick testing and in vitro determination of serum-specific IgE levels for aeroallergens, together with bronchial provocation with histamine and allergen. Results: The most common alteration identified through spirometry was obstructive lung disease, which was observed in 29 (47.5%) of the 62 patients evaluated. Eighteen (29.0%) of the 62 patients had a clinical history suggestive of allergic asthma. By the end of the study, asthma had been diagnosed in nine (14.5%) patients and atopy had been identified in six (9.7%). In addition, allergic asthma had been diagnosed in four patients (6.5% of the sample as a whole; 22.2% of the 18 patients with a clinical history suggestive of the diagnosis). Conclusion: In this study, CVID patients testing negative for specific IgE antibodies and suspected of having allergic asthma presented a positive response to bronchial provocation tests with allergens. To our knowledge, this is the first such study. When CVID patients with a history suggestive of allergic asthma test negative on traditional tests, additional tests designed to identify allergic asthma might be conducted.

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In breast cancer patients, primary chemotherapy is associated with the same survival benefits as adjuvant chemotherapy. Residual tumors represent a clinical challenge, Lis they may be resistant to additional cycles of the same drugs. Our aim was to identify differential transcripts expressed in residual tumors, after neoadjuvant chemotherapy, that might be related with tumor resistance. Hence, 16 patients with paired tumor samples, collected before and after treatment (4 cycles doxorubicin/cyclophosphamide, AC) had their gene expression evaluated on cDNA microarray slides containing 4,608 genes. Three hundred and eighty-nine genes were differentially expressed (paired Student`s t-test, pFDR<0.01) between pre- and post-chemotherapy samples and among the regulated functions were the JNK cascade and cell death. Unsupervised hierarchical clustering identified one branch comprising exclusively, eight pre-chemotherapy samples and another branch, including the former correspondent eight post-chemotherapy samples and other 16 paired pre/post-chemotherapy samples. No differences in clinical and tumor parameters could explain this clustering. Another group of I I patients with paired samples had expression of selected genes determined by real-time RT-PCR and CTGF and DUSP1 were confirmed more expressed in post- as compared to pre-chemotherapy samples. After neoadjuvant chemotherapy some residual samples may retain their molecular signature while others present significant changes in their gene expression, probably induced by the treatment. CTGF and DUSP1 overexpression in residual samples may be a reflection of resistance to further administration of AC regimen.