118 resultados para spatial frequency


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This prospective study analyzed the frequency of HLA-B27 and its alleles in 102 Brazilian patients with psoriatic arthritis (PsA). The association of the HLA-B27 alleles with these variants was compared to a control healthy HLA-B27 positive group of 111 individuals. There was a predominance of male gender (59.8%), Caucasian race (89.2%), and negative HLA-B27 (79.4%) patients. Asymmetric oligoarthritis (62.7%) was the most frequently observed clinical PsA subgroup, followed by spondylitis (16.7%), and polyarthritis (15.7%). Male gender and the spondylitis subgroup were statistically associated to the positive HLA-B27, and the oligoarthritis subgroup was associated to the negative HLA-B27. Among the 21 HLA-B27-positive PsA patients, there was a significant prevalence of the HLA-B*2705 allele (90.5%), similar to that observed in the control group (80.2%); HLA-B*2703 and HLA-B*2707 were statistically associated to the control group.

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This retrospective study analyzed the HLA-B*27 alleles in a group of 20 consecutive patients with the diagnosis of Reiter syndrome (RS) followed in a tertiary referral university hospital in Brazil, during the period 1990-2006, and compared the data with that observed in other patients with spondyloarthropathies followed at the same institution. Eight cases were associated to gastrointestinal infection, eight cases to previous urethritis, and four cases presented no established preceding infection. HLA-B*27 alleles were typed by polymerase chain reaction-amplified DNA hybridized with sequence-specific oligonucleotide probes (HLA-B*2701 to HLA-B*2721). They were compared to a group of 108 patients with ankylosing spondylitis (AS), 40 with undifferentiated spondyloarthropathy (uSpA) and 111 healthy controls. Among the 20 patients, 17 were HLA-B*27 positive (85%). Two HLA-B*27 alleles were observed: HLA-B*2705 (65%) and HLA-B*2702 (35%). In the other spondyloarthropathies, the observed alleles were HLA-B*2705 (90% in AS and 92.5% in uSpA), HLA-B*2702 (8% in AS and 5% in uSpA), HLA-B*2704 (1% in AS and 2.5% in uSpA) and HLA-B*2713 (1% in AS). Among the 111 healthy controls, 80% presented HLA-B*2705, followed by HLA-B*2702 in 10%, HLA-B*2703 in 6%, HLA-B*2707 in 3% and HLA-B*2713 in 1%. Concluding, in the HLA-B*27 positive patients with RS in this study there was predominance of HLA-B*2705 allele, in a lower frequency than that observed in patients with other spondyloarthropathies and healthy controls.

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Blood irradiation can be performed using a dedicated blood irradiator or a teletherapy unit. A thermal device providing appropriate storage conditions during blood components irradiation with a teletherapy unit has been recently proposed. However, the most appropriated volume of the thermal device was not indicated. The goal of this study was to indicate the most appropriated blood volume for irradiation using a teletherapy unit in order to minimize both the dose heterogeneity in the volume and the blood irradiation time using these equipments. Theoretical and experimental methods were used to study the dose distribution in the blood volume irradiated using a linear accelerator and a cobalt-60 therapy machine. The calculation of absorbed doses in the middle plane of cylindrical acrylic volumes was accomplished by a treatment planning system. Experimentally, we also used cylindrical acrylic phantoms and thermoluminescent dosimeters to confirm the calculated doses. The data obtained were represented by isodose curves. We observed that an irradiation volume should have a height of 28 cm and a diameter of 28 cm and a height of 35 cm and a diameter of 35 cm, when the irradiation is to be performed by a linear accelerator and a cobalt-60 teletherapy unit, respectively. Calculated values of relative doses varied from 93% to 100% in the smaller volume, and from 66% to 100% in the largest one. A difference of 5.0%, approximately, was observed between calculated and experimental data. The size of these volumes permits the irradiation of blood bags in only one bath without compromising the homogeneity of the absorbed dose over the irradiated volume. Thus, these irradiation volumes can be recommend to minimize the irradiation time when a teletherapy unit is used to irradiate blood. (C) 2010 Elsevier Ltd. All rights reserved.

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GLUT is the major glucose transporter in mammalian cells. Single nucleotide polymorphisms (SNP) at GLUT1 promoter and regulatory regions have been associated to the risk of developing nephropathy in different type 1 and type 2 diabetic populations. It has been demonstrated that differences in allelic and genotypic frequencies of GLUT1 gene (SLC2A1) polymorphisms occur among different populations. Therefore, ethnic differences in distribution of GLUT1 gene polymorphisms may be an important factor in determining gene-disease association. In this study, we investigated the XbaIG > T and HaeIIIT > C polymorphisms in six different Brazilian populations: 102 individuals from Salvador population (Northern Brazil), 56 European descendants from Joinville (South Brazil), 85 Indians from Tiryi tribe (North Brazil) and 127 samples from Southern Brazil: 44 from European descendants, 42 from African descendants and 41 from Japanese descendants. Genotype frequencies from both sites did not differ significantly from those expected under the Hardy-Weinberg equilibrium. We verified that the allele frequencies of both polymorphisms were heterogeneous in these six Brazilian ethnic groups.

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The role of nitric oxide (NO) in the caudal NTS (cNTS) on baseline cardiovascular and respiratory parameters and on changes in respiratory frequency (fR) and cardiovascular responses to chemoreflex activation was evaluated in awake rats. Bilateral microinjections of L-NAME (200 nmoles/50 nL), a non-selective NO synthase (NOS) inhibitor, into the cNTS increased baseline arterial pressure, while microinjections of NPLA (3 pmoles/50 nL), a selective neuronal NOS (nNOS) inhibitor, did not. L-NAME or N-PLA microinjected into the cNTS reduced the increase in fR in response to chemoreflex activation but not cardiovascular responses. These data show that (a) NO produced by non-nNOS in the cNTS is involved in the baseline autonomic control and (b) NO produced by nNOS in the cNTS is involved in modulation of the increase in fR in response to chemoreflex activation but not in the cardiovascular responses. We conclude that NO produced by the neuronal and endothelial NOS play a different role in the cNTS neurons integral to autonomic and respiratory pathways. (C) 2009 Elsevier B.V. All rights reserved.

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Purpose To determine the relationship between ocular hypertension and glaucoma in patients with Graves` orbitopathy. Methods A total of 107 patients with a diagnosis of Graves` orbitopathy, followed at the Oculoplasty sector of the University Hospital, Medical School of Ribeirao Preto, were evaluated by applanation tonometry, computed visual campimetry (Humphrey 30-2, Full Threshold) and analysis and photographic documentation of the optic nerve. The patients considered to have the suspicion of glaucoma were re-evaluated 1 year later for diagnostic confirmation or exclusion. Results A 3.74% prevalence of ocular hypertension (four patients) and a 2.8% prevalence of glaucoma (three patients) was observed. When considering only patients older than 40 years, the prevalence of ocular hypertension was 5.4% (four patients) and the prevalence of glaucoma was 4.76% (three patients). Conclusion The present study did not reveal a statistically significant difference in the prevalence of ocular hypertension or glaucoma between patients with Graves` orbitopathy and the general population.

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Objective: This study aimed to assess the relative validity of a food frequency questionnaire.(FFQ), previously validated to measure usual intakes in adults, for measuring dietary intakes in children 5 to 10 y of age. Methods: Dietary intakes were measured using an FFQ and a 3-d dietary record. Healthy children, 5 to 10 y old (n = 151), were recruited from public schools and asked to answer the questions in the FFQ and to provide non-consecutive 3-d dietary records based on reported estimated portion sizes. Paired sample t tests and Pearson`s correlation coefficients were conducted to determine whether the two instruments reported similar values for energy and nutrients. The agreement of quartile categorization between the two instruments was also examined. Results: Estimated energy and nutrient intakes derived from the FFQ were significantly higher than those derived from 3-d dietary records. As expected, Pearson`s correlations increased after adjusting for residual measurement error, presumably due to exclusion of the high within-person variability in intake of these nutrients. Moderate to high (r > 0.50) correlation coefficients were verified for some nutrients such as calcium, folate, vitamin 132, vitamin A, and vitamin C. Conclusion: This FFQ, originally developed for use in adults, appears to overestimate usual energy and nutrient intakes in children 5 to 10 y of age. Further work is necessary to conduct a calibration study to establish adequate portion sizes before instrument adoption in this population. (c) 2008 Elsevier Inc. All rights reserved.

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Human leukocyte antigen-G (HLA-G) is a non-classical major histocompatibility complex (MHC) class Ib molecule predominantly expressed in cytotrophoblasts, where it acts as a specific immunosuppressor. Literature data have shown that grafts in some settings, such as cardiac and liver/kidney-associated transplantations, express HLA-G and this expression is associated with less severe rejection and also reduces the incidence of rejection. Fourteen-base pair deletion/insertion polymorphism has been reported in exon 8 of the 3`-untranslated region of HLA-G. This polymorphism within exon 8 of the HLA-G gene might influence transcription activity, which in turn may influence the stability of HLA-G transcripts. This influences the stability of the HLA-G protein and therefore is of potential functional relevance. In order to determine a possible correlation between the 14-bp insertion/deletion polymorphism and kidney allograft outcome, we isolated genomic DNA from 83 patients who had received isolated kidney allografts, and we classified the 83 specimens into two groups, grafts presenting Banff features of rejection group and a non-rejection group, and compared them with a control group of 97 healthy subjects. The 14-bp polymorphism at exon 8 was genotyped in all groups. There was no significant difference in allelic frequencies of 14-bp insertion/deletion polymorphism between normal controls and kidney transplant patients. In the RG, the homozygous genotype +14/+14 bp (P = 0.0238) was significantly increased in the group with acute rejection compared with the healthy control group. Analysis of other HLA-G polymorphisms and functional studies on immune regulation are essential to elucidate the role of HLA-G in kidney allografts.

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The critically endangered black-faced lion tamarin, Leontopithecus caissara, has a restricted geographical distribution consisting of small mainland and island populations, each with distinct habitats in coastal southeastern Brazil. Necessary conservation management actions require an assessment of whether differences in habitats are reflected in use of space by the species. We studied two tamarin groups on the mainland at Sao Paulo state between August 2005 and March 2007, and compared the results with data from Superagui Island. Three home range estimators were used: minimum convex polygon (MCP), Kernel, and the new technique presented dissolved monthly polygons (DMP). These resulted, respectively, in home ranges of 345, 297, and 282 ha for the 12-month duration of the study. Spatial overlap of mainland groups was extensive, whereas temporal overlap was not, a pattern that indicates resource partitioning is an important strategy to avoid intraspecific competition. L. caissara large home ranges seem to be dynamic, with constant incorporation of new areas and abandonment of others through time. The main difference between mainland and island groups is the amount and variety of sleeping sites. A better understanding of the home range sizes, day range lengths, and territorial behavior of this species will aid in developing better management strategies for its protection. Additionally, the presented DMP protocol is a useful improvement over the MCP method as it results in more realistic home range sizes for wildlife species. Am. J. Primatol. 73: 1114-1126, 2011. (C) 2011 Wiley Periodicals, Inc.

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The maned wolf (Chrysocyon brachyurus) is the largest canid in South America, weighing up to 30 kg, and exhibits an omnivorous diet based on fruits and small vertebrates. Maned wolves are considered to live in monogamous pairs defending a common territory, with mates living a largely solitary life, but these conclusions come from few studies with small samples. We captured maned wolves in Emas National Park, central Brazil, and monitored their use of space using radiotelemetry. Home-range size and overlap of 45 adults, and interactions between members of 5 pairs, were investigated. Home-range sizes of resident adults averaged 80.18 km(2) using the fixed kernel with 95% of the locations, and averaged 13.78 km(2) with 50% of the locations. Overlap of 95% ranges between male-male, female-female, or mixed dyads was similar, approximately 0.20, whereas 50% ranges of maned wolves showed less overlap overall but more tolerance for overlap with the opposite sex. Members of a pair were located alone more often than together, and even when located simultaneously maintained a mean distance of >0.5 km apart, independent of time of day. Results are in agreement with a spatial organization based on monogamous mating pairs with little intrapair sociality, but the latter needs to be investigated in more detail.

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Oral squamous cell carcinoma (OSCC) is a cancerous lesion with high incidence worldwide. The immunoregulatory events leading to OSCC persistence remain to be elucidated. Our hypothesis is that regulatory T cells (Tregs) are important to obstruct antitumor immune responses in patients with OSCC. In the present study, we investigated the frequency, phenotype, and activity of Tregs from blood and lesions of patients with OSCC. Our data showed that > 80% of CD4(+)CD25(+) T cells isolated from PBMC and tumor sites express FoxP3. Also, these cells express surface Treg markers, such as GITR, CD45RO, CD69, LAP, CTLA-4, CCR4, and IL-10. Purified CD4(+)CD25(+) T cells exhibited stronger suppressive activity inhibiting allogeneic T-cell proliferation and IFN-gamma production when compared with CD4(+)CD25(+) T cells isolated from healthy individuals. Interestingly, approximately 25% of CD4(+)CD25(-) T cells of PBMC from patients also expressed FoxP3 and, although these cells weakly suppress allogeneic T cells proliferative response, they inhibited IFN-gamma and induced IL-10 and TGF-beta secretion in these co-cultures. Thus, our data show that Treg cells are present in OSCC lesions and PBMC, and these cells appear to suppress immune responses both systemically and in the tumor microenvironment.

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Considering that orthognathic surgery promotes changes in orofacial structures constituting the resonating system, functional changes secondary to surgery are expected to affect speech, leading to the need for further speech and voice adjustments. Thus, understanding the possible relationships of these structures with voice production is important. Therefore, this Study aimed to describe the changes in voice fundamental frequency of a patient submitted to orthognathic surgery and observe if there is a relationship with hyoid bone positioning at the different treatment periods. The results revealed that voice fundamental frequency increased after surgery, returning to values close to the preoperative condition, which corresponded to vertical movement of the hyoid bone.

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Objective: Patients using a removable prosthesis are susceptible to a variety of oral lesions that may progress to cancer. Toluidine blue (TB) staining is used to identify premalignant lesions, but the results are still controversial. Since micronuclei (MN) are a biomarker of genetic instability, the objective of this study was to determine the frequency of MN in white lesions of the oral mucosa and to compare the results with those of the TB test. Study Design: The study included 20 removable prosthesis users with white lesions that were previously classified as toluidine positive or negative. The frequency of MN was evaluated in exfoliated cells from lesions and normal mucosa. Nuclear anomalies were also registered. Results: A significant increase (p < 0.05) in the frequency of MN was observed in exfoliated cells from lesions compared to normal mucosal cells, and no relationship was seen with TB staining. Lifestyle factors or gender did not influence the results. Conclusions: The frequency of MN is a sensitive biomarker and can be used to predict genomic instability in white oral lesions. The MN assay may serve as a good parameter in the battery of tests used to identify high-risk individuals, contributing to the identification of the biological conditions of oral lesions. Copyright (C) 2011 S. Karger AG, Basel