855 resultados para objective-based coordination
Resumo:
Background: Neuropsychological deficits have been reported in association with first-episode psychosis (FEP). Reductions in grey matter (GM) volumes have been documented in FEP subjects compared to healthy controls. However, the possible inter-relationship between the findings of those two lines of research has been scarcely investigated. Objective: To investigate the relationship between neuropsychological deficits and GM volume abnormalities in a population-based sample of FEP patients compared to healthy controls from the same geographical area. Methods: FEP patients (n = 88) and control subjects (n = 86) were evaluated by neuropsychological assessment (Controlled Oral Word Association Test, forward and backward digit span tests) and magnetic resonance imaging using voxel-based morphometry. Results: Single-group analyses showed that prefrontal and temporo-parietal GM volumes correlated significantly (p < 0.05, corrected) with cognitive performance in FEP patients. A similar pattern of direct correlations between neocortical GM volumes and cognitive impairment was seen in the schizophrenia subgroup (n = 48). In the control group, cognitive performance was directly correlated with GM volume in the right dorsal anterior cingulate cortex and inversely correlated with parahippocampal gyral volumes bilaterally. Interaction analyses with ""group status"" as a predictor variable showed significantly greater positive correlation within the left inferior prefrontal cortex (BA46) in the FEP group relative to controls, and significantly greater negative correlation within the left parahippocampal gyrus in the control group relative to FEP patients. Conclusion: Our results indicate that cognitive deficits are directly related to brain volume abnormalities in frontal and temporo-parietal cortices in FEP subjects, most specifically in inferior portions of the dorsolateral prefrontal cortex. (C) 2009 Elsevier B.V. All rights reserved.
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Objective. To assess the histopathological, immunohistochemical (IHC), and in situ hybridization (ISH) features found in the submandibular (SM) and sublingual (SL) glands of 105 acquired immunodeficiency syndrome (AIDS) patients at autopsy. Study design. Gender, age, CD4 cell level, and clinical histories were obtained from clinical charts (SM: n = 103; SL: n = 92). Histologic analysis of hematoxylin and eosin, Gomori-Grocott, and Ziehl-Neelsen stained tissues, IHC to detect infectious agents and characterize inflammatory cells in sialadenitis, and ISH for EBER-1/2 were performed. Results. The mean age of the patients and CD4 cell count were 36 years and 76 cells/mu L, respectively. Fifty-eight cases (SM: n = 51 [49%]; SL: n = 54 [59%]) were considered to be microscopically normal. The most common infectious conditions were mycobacteriosis (SM: n = 11 [10%]; SL: n = 7 [7%]), followed by cytomegalovirus (CMV) (SM: n = 14 [13%]; SL: n = 2 [2%]), and cryptococcosis (SM: n = 3 [3%]; SL: n = 4 [4%]). Human immunodeficiency virus (HIV) p24 (SM: n = 2 [2%]; SL: n = 1 [1%]) and EBER-1/2 (SM: n = 9 [39%]; SL: n = 4 [20%]) were seen only in macrophages and lymphocytes, respectively. The most prevalent cells seen in chronic nonspecific sialadenitis (SM: n = 25; SL: n = 25) were CD8+ T lymphocytes, whereas CD68+ macrophages were predominant in the mycobacteriosis-associated granulomatous and nonspecific diffuse macrophagic sialadenitis. Concomitant infections occurred in 5 cases (SM: n = 4; SL: n = 1) and non-Hodgkin lymphoma in 1 case. Conclusions. Infectious diseases and chronic nonspecific sialadenitis were the main alterations found in the SM and SL glands. These alterations were greater in the SM than in the SL glands. CD8+ T lymphocytes and CD68+ macrophages might be relevant to the pathogenesis of the sialadenitis. Clinicians should consider these diseases when assessing the major salivary glands in advanced AIDS patients and follow biosafety procedures to avoid contamination by HIV, CMV, mycobacteriosis, and cryptococcosis. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: 216-226)
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Wastewater control at storage terminals of liquid chemical products in bulk is very difficult because of the variety of products handled in the facilities generating effluents of variable composition. The main objective of this work was to verify if the Vibrio fischeri acute toxicity test could be routinely included in the wastewater management of those facilities along with physical and chemical analysis in order to evaluate and improve the quality of the generated effluents. The study was performed in two phases before and after the implementation of better operational practices/treatment technologies. Chemical oxygen demand (COD) and toxicity of treated effluents did not correlate showing that effluents with low COD contain toxic substances and non-biodegradable organic matter, which may be not degraded when discharged into the aquatic environment. Segregation of influents or pre-treatment based on toxicity results and biodegradability index were implemented in the facilities generating significant improvements in the quality of final effluents with reduction of Biochemical oxygen demand (BOD) and toxicity. The integration of physical and chemical analysis with the V.fischeri toxicity test turned out to be an excellent tool for wastewater management in chemical terminals allowing rapid decision making for pollution control and prevention measures. Reuse of rain water was also proposed and when implemented by the facilities resulted in economical and environmental benefits. (C) 2010 Elsevier B.V. All rights reserved.
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Context Diffusion tensor imaging (DTI) studies in adults with bipolar disorder (BD) indicate altered white matter (WM) in the orbitomedial prefrontal cortex (OMPFC), potentially underlying abnormal prefrontal corticolimbic connectivity and mood dysregulatioin in BD. Objective: To use tract-based spatial statistics (TBSS) to examine VVM skeleton (ie, the most compact whole-brain WM) in subjects with BD vs healthy control subjects. Design: Cross-sectional, case-control, whole-brain DTI using TBSS. Setting: University research institute. Participants: Fifty-six individuals, 31 having a DSM-IV diagnosis of BD type 1 (mean age, 35.9 years [age range, 24-52 years]) and 25 controls (mean age, 29.5 years [age range, 19-52 years]). Main Outcome Measures: Fractional anisotropy (FA) longitudinal and radial diffusivities in subjects with BD vs controls (covarying for age) and their relationships with clinical and demographic variables. Results: Subjects with BD vs controls had significantly greater FA (t > 3.0, P <=.05 corrected) in the left uncinate fasciculus (reduced radial diffusivity distally and increased longitudinal diffusivity centrally), left optic radiation (increased longitudinal diffusivity), and right anterothalamic radiation (no significant diffusivity change). Subjects with BD vs controls had significantly reduced FA (t > 3.0, P <=.05 corrected) in the right uncinate fasciculus (greater radial diffusivity). Among subjects with BD, significant negative correlations (P <.01) were found between age and FA in bilateral uncinate fasciculi and in the right anterothalamic radiation, as well as between medication load and FA in the left optic radiation. Decreased FA (P <.01) was observed in the left optic radiation and in the right anterothalamic radiation among subjects with BD taking vs those not taking mood stabilizers, as well as in the left optic radiation among depressed vs remitted subjects with BD. Subjects having BD with vs without lifetime alcohol or other drug abuse had significantly decreased FA in the left uncinate fasciculus. Conclusions: To our knowledge, this is the first study to use TBSS to examine WM in subjects with BD. Subjects with BD vs controls showed greater WM FA in the left OMPFC that diminished with age and with alcohol or other drug abuse, as well as reduced WM FA in the right OMPFC. Mood stabilizers and depressed episode reduced WM FA in left-sided sensory visual processing regions among subjects with BD. Abnormal right vs left asymmetry in FA in OMPFC WM among subjects with BD, likely reflecting increased proportions of left-sided longitudinally aligned and right-sided obliquely aligned myelinated fibers, may represent a biologic mechanism for mood dysregulation in BD.
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Objective: To describe the findings of proton magnetic resonance spectroscopy (H-1-MRS) in Alzheimer`s disease (AD) and cognitive impairment, no dementia (CIND) elderly from a community-based sample. Methods: Thirteen patients with AD, 12 with CIND and 15 normal individuals were evaluated. The H-1-MRS was performed in the right temporal, left parietal and medial occipital regions studying the metabolites N-acetylaspartate (NAA), creatine (Cr), choline (Cho) and myoinositol (ml). The clinical diagnosis was based on standardized cognitive tests - MMSE and CAMDEX - and the results correlated with the H-1-MRS. Results: Parietal Cho was higher in control individuals and lower in CIND subjects. AD and control groups were better identified by temporal and parietal ml combined with the temporal NAA/Cr ratio. CIND was better identified by parietal Cho. Conclusion: The H-1-MRS findings confirmed the hypothesis that metabolic alterations are present since the first symptoms of cognitively impaired elderly subjects. These results suggest that combining MRS from different cerebral regions can help in the diagnosis and follow-up of community elderly individuals with memory complaints and AD. Copyright (C) 2008 S. Karger AG, Basel.
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The objective of this study was to evaluate the productive performance, nutrients digestion and metabolism of three different genetic groups fed with the same diet based on corn silage. 30 heifers in growth were used of three groups of cattle, the following: Nellore (Bos taurus indicus) (n = 10), Holstein (Bos taurus taurus) (n = 10), and Mediterranean buffaloes (Bubalis bubalis) (n = 10). The animals were fed in groups and received the same experimental diet composed of corn silage and concentrate for growing heifers. In the evaluation of animals the performance, consumption and total apparent digestibility of dry matter and nutrients with the aid of internal markers (chromic oxide) and external (iADF), rumen fermentation, excretion of purine derivatives, nitrogen balance and blood metabolites were measured. No differences were observed in animal performance. There were differences in nutrient intake and apparent digestibility of dry matter and nutrients in different groups of cattle. The concentration of ammonia nitrogen (NH3-N) and short chain fatty acids (SCFA) in the rumen were higher and lower, respectively, for the group of buffaloes in relation to other experimental groups evaluated. When considering the excretion of total purine derivatives, buffaloes showed the lowest value compared to other genetic groups evaluated; about 61.76% of the total genetic group Nellore and 57.62% of the total genetic group Holstein with an average of 33.67 mmol/day. For the buffaloes, the excretion of xanthine and hypoxanthine observed was of 5.11% of total purine derivatives. There was a better nitrogen balance (g/day) for groups of Holstein heifers and Nellore in relation to the group of buffalo heifers. There were differences in the concentrations of urea and urea nitrogen in serum and liver enzymes where the buffaloes had higher values in relation at the bovines. There is a great metabolic diversity among the experimental groups evaluated and it was more exacerbated among buffaloes and bovines, when submitted to the same diet and same management conditions. (C) 2011 Elsevier B.V. All rights reserved.
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The objective of this study was to evaluate the effects of treatment with an intravaginal progesterone-releasing device (CIDR) and estradiol benzoate (EB) on follicular dynamics in Bos indicus (n = 23), Bos taurus (n = 25), and cross-bred (n = 23) heifers. To assess the influence of reduced serum progesterone concentrations during 8 days of treatment with a progesterone-releasing device on follicular dynamics, half of the heifers received PGF at CIDR insertion (Day 0; 3 x 2 factorial design). Mean ( +/- S.E.M.) serum progesterone concentrations during CIDR treatment varied (P < 0.05) among genetic groups: B. indicus (5.4 +/- 0.1 ng/mL), B. taurus (3.3 +/- 0.0 ng/mL), and cross-bred (4.3 +/- 0.1 ng/mL). Maximum diameter of the dominant follicle (DF) was smaller (P < 0.01) in B. indicus heifers (9.5 +/- 0.5 mm) than in cross-bred (12.3 +/- 0.4 mm) or B. taurus heifers (11.6 +/- 0.5 mm). B. indicus experienced lower (P < 0.01) ovulation rate (39.1%) than did B. taurus (72.7%) and cross-bred (84.0%). Heifers treated with PGF on Day 0 had lower (P < 0.05) serum progesterone concentrations during progesterone treatment. The PGF treatment on Day 0 increased (P < 0.01) the diameter of the DF (11.9 +/- 0.4 mm vs. 10.5 +/- 0.4 mm). Moreover, greater (P = 0.02) ovulation rates (78.8 vs. 54.0%) occurred in heifers treated with PGF on Day 0. In summary, B. indicus heifers had greater serum progesterone concentrations, smaller DF diameter, and a lower ovulation rate compared to B. taurus heifers. Prostaglandin treatment on the day of CIDR insertion reduced serum progesterone during treatment, and resulted in increased maximum DF diameter and ovulation rate. (c) 2008 Elsevier Inc. All rights reserved.
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Our long-term objective is to devise reliable methods to generate biological replacement teeth exhibiting the physical properties and functions of naturally formed human teeth. Previously, we demonstrated the successful use of tissue engineering approaches to generate small, bioengineered tooth crowns from harvested pig and rat postnatal dental stem cells (DSCs). To facilitate characterizations of human DSCs, we have developed a novel radiographic staging system to accurately correlate human third molar tooth developmental stage with anticipated harvested DSC yield. Our results demonstrated that DSC yields were higher in less developed teeth (Stages 1 and 2), and lower in more developed teeth (Stages 3, 4, and 5). The greatest cell yields and colony-forming units (CFUs) capability was obtained from Stages 1 and 2 tooth dental pulp. We conclude that radiographic developmental staging can be used to accurately assess the utility of harvested human teeth for future dental tissue engineering applications.
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Objective. The purpose of this research was to provide further evidence to demonstrate the precision and accuracy of maxillofacial linear and angular measurements obtained by cone-beam computed tomography (CBCT) images. Study design. The study population consisted of 15 dry human skulls that were submitted to CBCT, and 3-dimensional (3D) images were generated. Linear and angular measurements based on conventional craniometric anatomical landmarks, and were identified in 3D-CBCT images by 2 radiologists twice each independently. Subsequently, physical measurements were made by a third examiner using a digital caliper and a digital goniometer. Results. The results demonstrated no statistically significant difference between inter-and intra-examiner analysis. Regarding accuracy test, no statistically significant differences were found of the comparison between the physical and CBCT-based linear and angular measurements for both examiners (P = .968 and .915, P = .844 and .700, respectively). Conclusions. 3D-CBCT images can be used to obtain dimensionally accurate linear and angular measurements from bony maxillofacial structures and landmarks. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: 430-436)
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Purpose: Orthodontic miniscrews are commonly used to achieve absolute anchorage during tooth movement. One of the most frequent complications is screw loss as a result of root contact. Increased precision during the process of miniscrew insertion would help prevent screw loss and potential root damage, improving treatment outcomes. Stereo lithographic surgical guides have been commonly used for prosthetic implants to increase the precision of insertion. The objective of this paper was to describe the use of a stereolithographic surgical guide suitable for one-component orthodontic miniscrews based on cone beam computed tomography (CBCT) data and to evaluate implant placement accuracy. Materials and Methods: Acrylic splints were adapted to the dental arches of four patients, and six radiopaque reference points were filled with gutta-percha. The patients were submitted to CBCT while they wore the occlusal splint. Another series of images was captured with the splint alone. After superimposition and segmentation, miniscrew insertion was simulated using planning software that allowed the user to check the implant position in all planes and in three dimensions. In a rapid-prototyping machine, a stereolithographic guide was fabricated with metallic sleeves located at the insertion points to allow for three-dimensional control of the pilot bur. The surgical guide was worn during surgery. After implant insertion, each patient was submitted to CBCT a second time to verify the implant position and the accuracy of the placement of the miniscrews. Results: The average differences between the planned and inserted positions for the ten miniscrews were 0.86 mm at the coronal end, 0.71 mm at the center, and 0.87 mm at the apical tip. The average angular discrepancy was 1.76 degrees. Conclusions: The use of stereolithographic surgical guides based on CBCT data allows for accurate orthodontic mini screw insertion without damaging neighboring anatomic structures. INT J ORAL MAXILLOFAC IMPLANTS 2011;26:860-865
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Objective. To evaluate the effect of two additives, aldehyde or diketone, on the wear, roughness and hardness of bis-GMA-based composites/copolymers containing TEGDMA, propoxylated bis-GMA (CH(3)bis-GMA) or propoxylated fluorinated bis-GMA (CF(3)bis-GMA). Methods. Fifteen experimental composites and 15 corresponding copolymers were prepared combining bis-GMA and TEGDMA, CH3bis-GMA or CF3bis-GMA, with aldehyde (24mol% and 32 mol%) or diketone (24 mol% and 32 mol%) totaling 30 groups. For composites, hybrid treated filler (barium aluminosilicate glass/pyrogenic silica; 60 wt%) was added to monomer mixtures. Photopolymerization was affected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Wear (W) test was conducted in a toothbrushing abrasion machine (n = 6) and quantified using a profilometer. Surface roughness (R) changes, before and after abrasion test, were determined using a rugosimeter. Microhardness (H) measurements were performed for dry and wet samples using a Knoop microindenter (n = 6). Data were analyzed by one-way ANOVA and Tukey`s test (alpha = 0.05). Results. Incorporation of additives led to improved W and H values for bis-GMA/TEGDMA and bis-GMA/CH(3)bis-GMA systems. Additives had no significant effect on the W and H changes of bis-GMA/CF(3)bis-GMA. With regard to R changes, additives produced decreased values for bis-GMA/CH3bis-GMA and bis-GMA/CF3bis-GMA composites. Bis-GMA/TEGDMA and bis-GMA/CH(3)bis-GMA copolymers with additives became smoother after abrasion test. Significance. The findings correlate with additives ability to improve degree of conversion of some composites/copolymers thereby enhancing mechanical properties. Published by Elsevier Ltd on behalf of Academy of Dental Materials
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Objective. To evaluate the effects of surface moisture (wet or dry) and storage (24h or 3 months) on the microtensile bond strength (BS) of resin/dentin bonds mediated by two water/ethanol based adhesives Single Bond, 3M-ESPE, (SB) and Opti Bond Solo Plus, Kerr, (OB), and two acetone-based adhesives, One Step, Bisco, (OS) and Prime&Bond NT, Caulk/Dentsply, (PB). Materials and methods. Flat dentin surfaces were polished with 600-grit SiC paper, etched with 35% phosphoric acid for 15 s and rinsed for 20 s. Half the surface was maintained moist and the other half was air-dried for 30 s. Each adhesive was applied simultaneously to both halves, left undisturbed for 30 s and light-cured. Four-mm resin build-ups were constructed incrementally. After storage in water at 37 degrees C for 24h, slabs were produced by transversal sectioning and trimmed to an hourglass shape (0.8 mm 2). Half of the specimens were tested in tension at 0.6 mm/min immediately after trimming and the other half after 3 months of water storage. Data were analyzed by two-way ANOVA and SNK for each material. Results. Both moisture and storage affected BS to dentin, and was material- dependent. Dry, bonding affected mostly the acetone-based adhesives. Larger reductions in bond strength were associated with dry bonding after 3 months of water storage. Significance. Wet bonding resulted in more stable bonds over 3 months of water storage for most of the materials tested. (C) 2007 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
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In the design of lattice domes, design engineers need expertise in areas such as configuration processing, nonlinear analysis, and optimization. These are extensive numerical, iterative, and lime-consuming processes that are prone to error without an integrated design tool. This article presents the application of a knowledge-based system in solving lattice-dome design problems. An operational prototype knowledge-based system, LADOME, has been developed by employing the combined knowledge representation approach, which uses rules, procedural methods, and an object-oriented blackboard concept. The system's objective is to assist engineers in lattice-dome design by integrating all design tasks into a single computer-aided environment with implementation of the knowledge-based system approach. For system verification, results from design examples are presented.
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Objective: To test the feasibility of an evidence-based clinical literature search service to help answer general practitioners' (GPs') clinical questions. Design: Two search services supplied GPs who submitted questions with the best available empirical evidence to answer these questions. The GPs provided feedback on the value of the service, and concordance of answers from the two search services was assessed. Setting: Two literature search services (Queensland and Victoria), operating for nine months from February 1999. Main outcome measures: Use of the service; time taken to locate answers; availability of evidence; value of the service to GPs; and consistency of answers from the two services. Results: 58 GPs asked 160 questions (29 asked one, 11 asked five or more). The questions concerned treatment (65%), aetiology (17%), prognosis (13%), and diagnosis (5%). Answering a question took a mean of 3 hours 32 minutes of personnel time (95% Cl, 2.67-3.97); nine questions took longer than 10 hours each to answer, the longest taking 23 hours 30 minutes. Evidence of suitable quality to provide a sound answer was available for 126 (79%) questions. Feedback data for 84 (53%) questions, provided by 42 GPs, showed that they appreciated the service, and asking the questions changed clinical care. There were many minor differences between the answers from the two centres, and substantial differences in the evidence found for 4/14 questions. However, conclusions reached were largely similar, with no or only minor differences for all questions. Conclusions: It is feasible to provide a literature search service, but further assessment is needed to establish its cost effectiveness.
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OBJECTIVE: To establish body mass index (BMI) norms for standard figural stimuli using a large Caucasian population-based sample. In addition, we sought to determine the effectiveness of the figural stimuli to identify individuals as obese or thin. DESIGN: All Caucasian twins born in Virginia between 1915 and 1971 were identified by public birth record. In addition, 3347 individual twins responded to a letter published in the newsletter of the American Association of Retired Persons (AARP). All adult twins (aged 18 and over) from both of these sources and their family members were mailed a 16 page 'Health and Lifestyle' questionnaire. SUBJECTS: BMI and silhouette data were available on 16 728 females and 11 366 males ranging in age from 18- 100. MEASUREMENTS: Self-report information on height-weight, current body size, desired body size and a discrepancy score using standard figural stimuli. RESULTS: Gender- and age-specific norms are presented linking BMI to each of the figural stimuli. Additional norms for desired body size and discrepancy scores are also presented. Receiver operating curves (ROC) indicate that the figural stimuli are effective in classifying individuals as obese or thin. CONCLUSIONS: With the establishment of these norms, the silhouettes used in standard body image assessment can now be linked to BMI. Differences were observed between women and men in terms of desired body size and discrepancy scores, with women preferring smaller sizes. The figural stimuli are a robust technique for classifying individuals as obese or thin.