997 resultados para Domain age


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Purpose The aim of this study was to test the correlation between Fourier-domain (FD) optical coherence tomography (OCT) macular and retinal nerve fibre layer (RNFL) thickness and visual field (VF) loss on standard automated perimetry (SAP) in chiasmal compression. Methods A total of 35 eyes with permanent temporal VF defects and 35 controls underwent SAP and FD-OCT (3D OCT-1000; Topcon Corp.) examinations. Macular thickness measurements were averaged for the central area and for each quadrant and half of that area, whereas RNFL thickness was determined for six sectors around the optic disc. VF loss was estimated in six sectors of the VF and in the central 16 test points in the VF. The correlation between VF loss and OCT measurements was tested with Spearman`s correlation coefficients and with linear regression analysis. Results Macular and RNFL thickness parameters correlated strongly with SAP VF loss. Correlations were generally stronger between VF loss and quadrantic or hemianopic macular thickness than with sectoral RNFL thickness. For the macular parameters, we observed the strongest correlation between macular thickness in the inferonasal quadrant and VF loss in the superior temporal central quadrant (rho=0.78; P<0.001) whereas for the RNFL parameters the strongest correlation was observed between the superonasal optic disc sector and the central temporal VF defect (rho=0.60; P<0.001).

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The myosin-associated giant protein kinases twitchin and titin are composed predominantly of fibronectin- and immunoglobulin-like modules, We report the crystal structures of two autoinhibited twitchin kinase fragments, one from Aplysia and a larger fragment from Caenorhabditis elegans containing an additional C-terminal immunoglobulin-like domain, The structure of the longer fragment shoes that the immunoglobulin domain contacts the protein kinase domain on the opposite side from the catalytic cleft, laterally exposing potential myosin binding residues, Together, the structures reveal the cooperative interactions between the autoregulatory region and the residues from the catalytic domain involved in protein substrate binding, ATP binding, catalysis and the activation loop, and explain the differences between the observed autoinhibitory mechanism and the one found in the structure of calmodulin-dependent kinase I.

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Objective: to determine the relationship between age and in-hospital mortality of elderly patients, admitted to ICU, requiring and not requiring invasive ventilatory support. Design: prospective observational cohort study conducted over a period of 11 months. Setting: medical-surgical ICU at a Brazilian university hospital. Subjects: a total of 840 patients aged 55 years and older were admitted to ICU. Methods: in-hospital death rates for patients requiring and not requiring invasive ventilatory support were compared across three successive age intervals (55-64; 65-74 and 75 or more years), adjusting for severity of illness using the Acute Physiologic Score. Results: age was strongly correlated with mortality among the invasively ventilated subgroup of patients and the multivariate adjusted odds ratios increased progressively with every age increment (OR = 1.60, 95% CI = 1.01-2.54 for 65-74 years old and OR = 2.68, 95% CI = 1.58-4.56 for >= 75 years). For the patients not submitted to invasive ventilatory support, age was not independently associated with in-hospital mortality (OR = 2.28, 95% CI = 0.99-5.25 for 65-74 years old and OR = 1.95, 95% CI = 0.82-4.62 for >= 75 years old). Conclusions: the combination of age and invasive mechanical ventilation is strongly associated with in-hospital mortality. Age should not be considered as a factor related to in-hospital mortality of elderly patients not requiring invasive ventilatory support in ICU.

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Mutations in PKD2 are responsible for approximately 15% of the autosomal dominant polycystic kidney disease cases. This gene encodes polycystin-2, a calcium-permeable cation channel whose C-terminal intracytosolic tail (PC2t) plays an important role in its interaction with a number of different proteins. In the present study, we have comprehensively evaluated the macromolecular assembly of PC2t homooligomer using a series of biophysical and biochemical analyses. Our studies, based on a new delimitation of PC2t, have revealed that it is capable of assembling as a homotetramer independently of any other portion of the molecule. Our data support this tetrameric arrangement in the presence and absence of calcium. Molecular dynamics simulations performed with a modified all-atoms structure-based model supported the PC2t tetrameric assembly, as well as how different populations are disposed in solution. The simulations demonstrated, indeed, that the best-scored structures are the ones compatible with a fourfold oligomeric state. These findings clarify the structural properties of PC2t domain and strongly support a homotetramer assembly of PC2.

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The SH3 domains of src and other nonreceptor tyrosine kinases have been shown to associate with the motif PXXP, where P and X stand for proline and an unspecified amino acid, but a motif that binds to the SH3 domain of myosin has thus far not been characterized. We previously showed that the SH3 domain of Acanthamoeba myosin-IC interacts with the protein Acan125. We now report that the Acan125 protein sequence contains two tandem consensus PXXP motifs near the C terminus. To test for binding, we expressed a polypeptide, AD3p, which includes 344 residues of native C-terminal sequence and a mutant polypeptide, AD3 Delta 977-994p, which lacks the sequence RPKPVPPPRGAKPAPPPR containing both PXXP motifs. The SH3 domain of Acanthamoeba myosin-IC bound AD3p and not AD3 Delta 977-994p, showing that the PXXP motifs are required for SH3 binding. The sequence of Acan125 is related overall to a protein of unknown function coded by Caenorhabditis elegans gene K07G5.1. The K07G5.1 gene product contains a proline-rich segment similar to the SH3 binding motif found in Acan125. The aligned sequences show considerable conservation of leucines and other hydrophobic residues, including the spacing of these residues, which matches a motif for leucine-rich repeats (LRRs). LRR domains have been demonstrated to be sites for ligand binding. Having an LRR domain and an SH3-binding domain, Acan125 and the C. elegans homologue define a novel family of bifunctional binding proteins.

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Objective Cardiovascular risk factors were surveyed in two Indian populations (Guarani, n=60; Tupinikin, n=496) and in a non-Indian group (n=114) living in the same reserve in southeast Brazilian coast. The relationship between an age-dependent blood pressure (BP) increase with salt consumption was also investigated. Methods Overnight (12 h) urine was collected to evaluate Na excretion. Fasting glucose and lipids, anthropometry, BP, ECG and carotid-femoral pulse wave velocity (PWV) were measured in a clinic visit. Participation (318 men/352 women, age 20-94 years; mean=37.6 +/- 14.9 years) comprised 80% of the eligible population. Results The prevalence of hypertension, diabetes and high cholesterol was similar in Tupinikins and in non-Indians and higher than in Guaranis. The prevalence of smoking and obesity was higher in the latter group. Hypertension and diabetes were detected in only one individual of the Guarani group. Mean BP adjusted to age and BMI was significantly lower (P<0.01) in Guaranis (82.8 +/- 1.6 mmHg) than in Tupinikins (92.3 +/- 0.5 mmHg) and non-Indians (91.6 +/- 1.1 mmHg). Urinary Na excretion (mEq/12h), however, was similar in the three groups (Guarani=94 +/- 40; Tupinikin=105 +/- 56; non-Indian=109 +/- 55; P>0.05). PWV (m/s) was lower (P<0.01) in Guarani (7.5 +/- 1.4) than in Tupinikins (8.8 +/- 2.2) and non-Indians (8.4 +/- 2.0). Multiple regression analysis showed that age and waist-to-hip ratio (WHR) were independent predictors of SBP and DBP (r(2)=0.44) in Tupinikins, whereas the WHR was the unique independent predictor of BP variability in Guaranis (r(2)=0.22). Conclusion Lower BP levels in Guaranis cannot be explained by low salt intake observed in other primitive populations. J Hypertens 27:1753-1760 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

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Previous magnetic resonance imaging (MRI) studies described consistent age-related gray matter (GM) reductions in the fronto-parietal neocortex, insula and cerebellum in elderly subjects, but not as frequently in limbic/paralimbic structures. However, it is unclear whether such features are already present during earlier stages of adulthood, and if age-related GM changes may follow non-linear patterns at such age range. This voxel-based morphometry study investigated the relationship between GM volumes and age specifically during non-elderly life (18-50 years) in 89 healthy individuals (48 males and 41 females). Voxelwise analyses showed significant (p < 0.05, corrected) negative correlations in the right prefrontal cortex and left cerebellum, and positive correlations (indicating lack of GM loss) in the medial temporal region, cingulate gyrus, insula and temporal neocortex. Analyses using ROI masks showed that age-related dorsolateral prefrontal volume decrements followed non-linear patterns, and were less prominent in females compared to males at this age range. These findings further support for the notion of a heterogeneous and asynchronous pattern of age-related brain morphometric changes, with region-specific non-linear features. (C) 2009 Elsevier Inc. All rights reserved.

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Study objective-To investigate asthma mortality during 1920-94 in Australia in order to assess the relative role of period and birth cohort effects. Design-Asthma mortality (both sexes) was age standardised and examined for changes over time. The data were also examined for age, period, and cohort (APC) effects using Poisson regression modelling. Setting-National Australian mortality data. Participants-Population (both sexes) aged 15-34 years, 1920-94. Main results-Age adjusted period rates indicate an increase in asthma mortality during the 1950s, and increases and subsequent falls (epidemics) during the mid 1960s and late 1980s. APC modelling suggested an increasing cohort effect (adjusted for both age and period) from the birth cohort 1950-54 onwards. Period effects (adjusted for age and cohort) are characterised by an increase in the 1950s (possibly due to changes in diagnostic labelling), minimal or no increases in the mid 1960s and late 1980s (where period peaks had been noted when data were adjusted for age only), and declines in mortality risk subsequent to the periods where age-period analysis had noted increases. Thus, in Australia, some of the mid 1960s epidemic in asthma deaths, and all of the late 1980s mortality increase, seem to be attributable to cohort effects. Conclusions-The increase in asthma mortality cohort effect is consistent with empirical evidence of recent increases in prevalence (and presumably incidence) of asthma in Australia, and suggests the need for more research into the underlying environmental aetiology of this condition.

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Background: Concurrent autoimmune disorders (CAIDs) have been shown to occur in 22% to 34% of the patients with autoimmune hepatitis (AIH). Their presence has been linked to female gender, older age, and to certain HLA antigens, namely HLA-A11. DRB1*04, and DRB4*01. Aims: To assess the frequency and nature of CAID in Brazilian patients with AIH types 1 (AIH-1) and 2 (AIH-2) and to investigate the influence of age, gender, and genetic background in their occurrence. Patients and Methods: The presence and nature of CAID was studied in 143 patients [117 females, median age 11 (1.3 to 69)] with AIH-1 (n = 125) and AIH-2 (n = 28). HLA typing and tumor necrosis factor a gene promoter and exon I cytotoxic T lymphocyte associated antigen 4 (CTLA-4) gene polymorphisms were determined by polymerase chain reaction-based techniques. Results: The frequency of CAID was similar in patients with AIH-1 (14%) and AIH-2 (18%), but their nature was shown to vary. Arthritis was seen in half of the patients (n = 8) with CAID and AIH-1 and in none of those with AIH-2. Subjects with AIH-1 and CAID were shown to be older [24 (1.3 to 6 1) vs. 11 (1.3 to 69) y P = 0.02] and to have more often circulating antinuclear antibody (76% vs. 40%, P = 0.008) and less frequently antiactin antibodies (33% vs. 75%, P = 0.008) when compared with their counterparts without CAID. No particular HLA-DR and DQ alleles, as well as tumor necrosis factor a and CTLA-4 genotypes, were associated with CAID. Conclusions: The nature, but not the frequency, of CAID was shown to vary in AIH-1 and AIH-2. In subjects with AIH-1, CAID was linked to older subjects and to the presence of antinuclear antibody. No predisposition to CAID was associated to HLA-DRB1*04 or DDB4*01 alleles. The observed lower frequency of CAID could be attributed to the lower age of disease onset in Brazilians and to differences in HLA-encoded susceptibility to AIH-1 observed in South America.

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Fuzzy Bayesian tests were performed to evaluate whether the mother`s seroprevalence and children`s seroconversion to measles vaccine could be considered as ""high"" or ""low"". The results of the tests were aggregated into a fuzzy rule-based model structure, which would allow an expert to influence the model results. The linguistic model was developed considering four input variables. As the model output, we obtain the recommended age-specific vaccine coverage. The inputs of the fuzzy rules are fuzzy sets and the outputs are constant functions, performing the simplest Takagi-Sugeno-Kang model. This fuzzy approach is compared to a classical one, where the classical Bayes test was performed. Although the fuzzy and classical performances were similar, the fuzzy approach was more detailed and revealed important differences. In addition to taking into account subjective information in the form of fuzzy hypotheses it can be intuitively grasped by the decision maker. Finally, we show that the Bayesian test of fuzzy hypotheses is an interesting approach from the theoretical point of view, in the sense that it combines two complementary areas of investigation, normally seen as competitive. (C) 2007 IMACS. Published by Elsevier B.V. All rights reserved.

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Tinnitus is a symptom present in approximately 15% of the world population. Most patients are between 40 and 80 years of age; the prevalence above 60 reaches 33%. About 20% have moderate to severe impact in the quality of life but the factors associated with the tinnitus annoyance are not completely known. Aim: The objective of this study is to evaluate the relationship between age, gender and hearing loss on tinnitus annoyance. Materials and methods: 68 patients were evaluated at the tinnitus center at our hospital, from March 2007 to march 2008, with a detailed interview, complete otolaryngological examination, the Portuguese version of the Tinnitus Handicap Inventory and pure tone audiometry. Results: Age varied from 24 to 83 (mean=59); the mean THI value was 39 (females: 36; males: 44). THI grades were: slight: 32.3%; mild: 19.1%; moderate: 20.6%; severe: 13.2% and catastrophic: 14.7%. No significant correlation was found between gender (p=0.30), age (p=0.77) hearing loss (p>0.05 for all averages analyzed) and tinnitus severity. Conclusion: Gender, age and hearing loss do not influence tinnitus annoyance, using the THI.

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PURPOSE: To compare the ability of Fourier-domain (FD) optical coherence tomography (3D OCT-1000; Top, con, Tokyo, Japan) and time domain (TD) OCT (Stratus; Carl Zeiss Meditec Inc, Dublin, California, USA) to detect axonal loss in eyes with band atrophy (BA) of the optic nerve. DESIGN: Cross-sectional study. METHODS: Thirty-six eyes from 36 patients with BA and temporal visual field (VF) defect from chiasmal compression and 36 normal eyes were studied. Subjects were submitted to standard automated perimetry and macular and retinal nerve fiber layer (RNFL) measurements were taken using 3D OCT-1000 and Stratus OCT. Receiver operating characteristic (ROC) curves were calculated for each parameter. Spearman correlation coefficients were obtained to evaluate the relationship between RNFL and macular thickness parameters and severity of VF loss. Measurements from the two devices were compared. RESULTS: Regardless of OCT device, all RNFL and macular thickness parameters were significantly lower in eyes with BA compared with normal eyes, but no statistically significant difference was found with regard to the area under the ROC curve. Structure-function relationships were also similar for the two devices. In both groups, RNFL and macular thickness measurements were generally and in some cases significantly smaller with 3D OCT-1000 than with Stratus OCT. CONCLUSIONS: The introduction of FD technology did not lead to better discrimination ability for detecting BA of the optic nerve compared with TD technology when using the software currently provided by the manufacturer. 3D OCT-1000 FD OCT RNFL and macular measurements were generally smaller than TD Stratus OCT measurements. Investigators should be aware of this fact when comparing measurements obtained with these two devices. (Am J Oplathalmol 2009;147: 56-63. (c) 2009 by Elsevier Inc. All rights reserved.)

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Objective. To correlate Doppler results with hematological indices at birth in small-for-gestational-age (SGA) fetuses. Design. Prospective study. Setting. Tertiary teaching hospital, Sao Paulo, Brazil. Population. One hundred singleton pregnancies with SGA fetuses of > 27 weeks gestational age. Methods. All women had Doppler velocimetry of the umbilical arteries, middle cerebral artery, and ductus venosus within < 72 hours prior to delivery. After birth, umbilical artery blood was collected for hematological analysis. Main outcome measures. The association between fetal Doppler velocimetry pulsatility index (PI) and some hematological indices. Results. Umbilical artery PI showed a positive correlation with nucleated red blood cell count in the umbilical cord (r = 0.46; p<0.01), and a negative correlation with platelet count (r = -0.53; p<0.01) and white blood cell count (r = -0.42; p<0.01). Middle cerebral artery PI was positively correlated with platelet count (r = 0.43; p<0.01) and white blood cell count (r = 0.38; p<0.01), and was negatively correlated with nucleated red blood cell count (r = -0.39; p<0.01). The ductus venosus pulsatility index showed a positive correlation with nucleated red blood cell count (r = 0.36; p<0.01), and a negative correlation with platelet count (r = -0.37; p<0.01) and white blood cell count (r = -0.26; p<0.01). Conclusion. A significant positive or negative correlation between nucleated red blood cell, platelet and white blood cell counts, and Doppler indices suggests an association between placental insufficiency and the fetal hematological response.

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Purpose of review To review neuroimaging findings that have been reported in samples of patients with cardiovascular disorders and their association with the onset of Alzheimer`s disease, vascular dementia, depression and bipolar disorder in the elderly and to highlight the implications of these findings to the knowledge about the pathophysiology of psychiatric disorders in old age, as well as their potential clinical implications. Recent findings Vascular risk factors, such as hypertension, diabetes, dyslipidemia, smoking habits and heart failure, have all been associated with signs of cerebrovascular dysfunction, including structural MRI findings of signal hyperintensities, lacunes and stroke and functional imaging findings of brain regional hypoperfusion and hypometabolism. Such brain abnormalities have been found to increase the risk of onset of psychiatric disorder (depression, bipolar and dementia) in old age. Summary As vascular risk factors are potentially modifiable when detected in midlife, the early characterization of brain changes associated with the presence of cardiovascular diseases holds promise to afford clinical applications in psychiatry, providing new perspectives for the prevention of old age psychiatric disorders.

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Cognitive deficits are a key feature of recent-onset psychosis, but there is no consensus on whether such deficits are generalized or confined to specific domains. Besides, it is unclear whether cognitive deficits: a) are found in psychotic patients in samples from outside high-income countries; and b) whether they progress uniformly over time in schizophrenia and affective psychoses. We applied 12 tests organized into eight cognitive domains, comparing psychosis patients (n = 56, time from initial contact = 677.95+/-183.27 days) versus healthy controls (n = 70) recruited from the same area of Sao Paulo, Brazil. Longitudinal comparisons (digit span and verbal fluency) were conducted between a previous assessment of the subjects carried out at their psychosis onset, and the current follow-up evaluation. Psychosis patients differed significantly from controls on five domains, most prominently on verbal memory. Cognitive deficits remained detectable in separate comparisons of the schizophrenia subgroup and, to a lesser extent, the affective psychosis subjects against controls. Longitudinal comparisons indicated significant improvement in schizophrenia, affective psychoses, and control subjects, with no significant group-by-time interactions. Our results reinforce the view that there are generalized cognitive deficits in association with recent-onset psychoses, particularly of non-affective nature, which persist over time. (C) 2009 Elsevier Ireland Ltd. All rights reserved.