948 resultados para 6 minutes walk test
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Background and purpose: D-Fructose-1,6-bisphosphate (FBP) is an intermediate in the glycolytic pathway, exerting pharmacological actions on inflammation by inhibiting cytokine production or interfering with adenosine production. Here, the possible antinociceptive effect of FBP and its mechanism of action in the carrageenin paw inflammation model in mice were addressed, focusing on the two mechanisms described above. Experimental approach: Mechanical hyperalgesia (decrease in the nociceptive threshold) was evaluated by the electronic pressure-metre test; cytokine levels were measured by elisa and adenosine was determined by high performance liquid chromatography. Key results: Pretreatment of mice with FBP reduced hyperalgesia induced by intraplantar injection of carrageenin (up to 54%), tumour necrosis factor alpha (40%), interleukin-1 beta (46%), CXCL1 (33%), prostaglandin E(2) (41%) or dopamine (55%). However, FBP treatment did not alter carrageenin-induced cytokine (tumour necrosis factor alpha and interleukin-1 beta) or chemokine (CXCL1) production. On the other hand, the antinociceptive effect of FBP was prevented by systemic and intraplantar treatment with an adenosine A(1) receptor antagonist (8-cyclopentyl-1,3-dipropylxanthine), suggesting that the FBP effect is mediated by peripheral adenosine acting on A(1) receptors. Giving FBP to mice increased adenosine levels in plasma, and adenosine treatment of paw inflammation presented a similar antinociceptive mechanism to that of FBP. Conclusions and implications: In addition to anti-inflammatory action, FBP also presents an antinociceptive effect upon inflammatory hyperalgesia. Its mechanism of action seems dependent on adenosine production but not on modulation of hyperalgesic cytokine/chemokine production. In turn, adenosine acts peripherally on its A(1) receptor inhibiting hyperalgesia. FBP may have possible therapeutic applications in reducing inflammatory pain.
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SETTING: Five medical schools in three cities in Rio de Janeiro State, Brazil, with different tuberculosis (TB) incidence rates. OBJECTIVE: To evaluate the prevalence of the booster phenomenon and its associated factors in a voting universally BCG-vaccinated TB-exposed population. DESIGN: A two-step tuberculin skin test (TST) was performed among undergraduate medical students. Boosting was defined as an induration >= 10 mm in the second TST (TST2), with an increase of at least 6 mm over the first TST (TST1). The association of boosting with independent variables was evaluated using multivariate analysis. RESULTS: Of the 764 participants (mean age 21.9 +/- 2.7 years), 672 (87.9%) had a BCG scar. The overall booster SUMMARY phenomenon prevalence was 8.4% (95%CI 6.5-10.6). Boosting was associated with TST1 reactions of 1-9 mm (aOR 2.5, 95%CI 1.04-5.9) and with BCG vaccination, mostly after infancy, i.e., after age two years (aOR 9.1, 95%,CI 1.2-70.7). CONCLUSION: The prevalence of the booster phenomenon was high. A two-step TST in young BCG-vaccinated populations, especially in those with TST1 reactions of 1-9 mm, can avoid misdiagnosis as a false conversion and potentially reduce unnecessary treatment for latent TB infection.
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Context Novel therapies have improved the remission rate in chronic inflammatory disorders including juvenile idiopathic arthritis (JIA). Therefore, strategies of tapering therapy and reliable parameters for detecting subclinical inflammation have now become challenging questions. Objectives To analyze whether longer methotrexate treatment during remission of JIA prevents flares after withdrawal of medication and whether specific biomarkers identify patients at risk for flares. Design, Setting, and Patients Prospective, open, multicenter, medication-withdrawal randomized clinical trial including 364 patients (median age, 11.0 years) with JIA recruited in 61 centers from 29 countries between February 2005 and June 2006. Patients were included at first confirmation of clinical remission while continuing medication. At the time of therapy withdrawal, levels of the phagocyte activation marker myeloid-related proteins 8 and 14 heterocomplex (MRP8/14) were determined. Intervention Patients were randomly assigned to continue with methotrexate therapy for either 6 months (group 1 [n = 183]) or 12 months (group 2 [n = 181]) after induction of disease remission. Main Outcome Measures Primary outcome was relapse rate in the 2 treatment groups; secondary outcome was time to relapse. In a prespecified cohort analysis, the prognostic accuracy of MRP8/14 concentrations for the risk of flares was assessed. Results Intention-to-treat analysis of the primary outcome revealed relapse within 24 months after the inclusion into the study in 98 of 183 patients (relapse rate, 56.7%) in group 1 and 94 of 181 (55.6%) in group 2. The odds ratio for group 1 vs group 2 was 1.02 (95% CI, 0.82-1.27; P=.86). The median relapse-free interval after inclusion was 21.0 months in group 1 and 23.0 months in group 2. The hazard ratio for group 1 vs group 2 was 1.07 (95% CI, 0.82-1.41; P=.61). Median follow-up duration after inclusion was 34.2 and 34.3 months in groups 1 and 2, respectively. Levels of MRP8/14 during remission were significantly higher in patients who subsequently developed flares (median, 715 [IQR, 320-1110] ng/mL) compared with patients maintaining stable remission (400 [IQR, 220-800] ng/mL; P=.003). Low MRP8/14 levels indicated a low risk of flares within the next 3 months following the biomarker test (area under the receiver operating characteristic curve, 0.76; 95% CI, 0.62-0.90). Conclusions In patients with JIA in remission, a 12-month vs 6-month withdrawal of methotrexate did not reduce the relapse rate. Higher MRP8/14 concentrations were associated with risk of relapse after discontinuing methotrexate.
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Objective-To compare analgesic effects of tramadol, codeine, and ketoprofen administered alone and in combination and their effects on concentrations of blood glucose, serum cortisol, and serum interleukin (IL)-6 in dogs undergoing maxillectomy or mandibulectomy. Animals-42 dogs with oral neoplasms. Procedures-30 minutes before the end of surgery, dogs received SC injections of tramadol (2 mg/kg), codeine (2 mg/kg), ketoprofen (2 mg/kg), tramadol + ketoprofen, or codeine + ketoprofen (at the aforementioned dosages). Physiologic variables, analgesia, and sedation were measured before (baseline) and 1, 2, 3, 4, 5, and 24 hours after surgery. Blood glucose, serum cortisol, and serum IL-6 concentrations were measured 1, 3, 5, and 24 hours after administration of analgesics. Results-All treatments provided adequate postoperative analgesia. Significant increases in mean +/- SD blood glucose concentrations were detected in dogs receiving tramadol (96 +/- 14 mg/dL), codeine (120 +/- 66 mg/dL and 96 +/- 21 mg/dL), ketoprofen (105 +/- 22 mg/dL), and codeine + ketoprofen (104 +/- 16 mg/dL) at 5, 1 and 3, 5, and 3 hours after analgesic administration, respectively, compared with preoperative (baseline) values. There were no significant changes in physiologic variables, serum IL-6 concentrations, or serum cortisol concentrations. Dogs administered codeine + ketoprofen had light but significant sedation at 4, 5, and 24 hours. Conclusions and Clinical Relevance-Opioids alone or in combination with an NSAID promoted analgesia without adverse effects during the 24-hour postoperative period in dogs undergoing maxillectomy or mandibulectomy for removal of oral neoplasms. (Am J Vet Res 2010;71:1019-1026)
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The hepatic effects of the anesthetic association zolazepam/tiletamine were investigated in dogs by analyzing the serum concentration of hepatic enzymes. Ten healthy dogs were divided into two groups of five, group I (GI) and group II (GII). The animals of GI received a single dose of 6,6 mg/kg of zolazepam/tiletamine, by intramuscular (IM) injection. GII dogs received 6,6 mg/kg of zolazepam/tiletamine by the IM route; after a period of 50 - 80 minutes the animals received two additional doses (3,3 mg/kg) by intravenous administration[SAH1]. The hepatic function were analyzed by monitoring the serum concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl-transferase (GGT). Four blood samples were collected in different moments during the analyses: M0, before the first application of the drug; and M1 to M4. M1 through M3 was collected with intervals of 20 minutes before M0, while M4 was obtained 24 hours after M1. The normality of the obtained results was analyzed by Kolmogorov-Smirnov Test; while the Tukey`s test compared the means, using a level of significance of 5% for both statistical analyses. The mean values of all enzymes evaluated were within normal limits for both experimental groups, without any significant statistical alteration being observed between and within these groups. These results demonstrated that the association of zolazepam/tiletamine at the dosage of 6.6 mg/kg, followed by two applications additional of 3.3 mg/kg resulted in elevation of the evaluated hepatic enzymes without exceeding the physiologic values. Additionally, a single application of 6.6 mg/kg of zolazepam/tiletamine by the intramuscular route resulted in lower values when compared to three applications.
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Objective To establish the correlation between the bispectral index (BIS) and different rates of infusion of propofol in dogs. Study design Prospective experimental trial. Animals Eight adult dogs weighing 6-20 kg. Methods Eight animals underwent three treatments at intervals of 20 days. Propofol was used for induction of anesthesia (10 mg kg(-1) IV), followed by a continuous rate infusion (CRI) at 0.2 mg kg(-1) minute(-1) (P2), 0.4 mg kg(-1) minute(-1) (P4) or 0.8 mg kg(-1) minute(-1) (P8) for 55 minutes. The BIS values were measured at 10, 20, 30, 40, and 50 minutes (T10, T20, T30, T40, and T50, respectively) after the CRI of propofol was started. Numeric data were submitted to analysis of variance followed by Tukey test (p < 0.05). Results The BIS differed significantly among groups at T40, when P8 was lower than P2 and P4. At T50, P8 was lower than P2. The electromyographic activity (EMG) in P2 and P4 was higher than P8 at T40 and T50. Conclusion An increase in propofol infusion rates decreases the BIS values and EMG.
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Objective: The purpose of the study was to investigate whether dentine irradiation with a pulsed CO(2) laser (10.6 mu m) emitting pulses of 10 ms is capable of reducing dentine calcium and phosphorus losses in an artificial caries model. Design: The 90 dentine slabs obtained from bovine teeth were randomly divided into six groups (n = 15): negative control group (GC); positive control group, treated with fluoride 1.23% (GF); and laser groups irradiated with 8 J/cm(2) (L8); irradiated as in L8 + fluoride 1.23% (L8F); irradiated with 11j/cm(2) (L11); irradiated as in L11 + fluoride 1.23% (L11F). After laser irradiation the samples were submitted to a pH-cycling model for 9 days. The calcium and phosphorous contents in the de- and remineralization solutions were measured by means of inductively coupled plasma optical emission spectrometer - ICP-OES. Additionally intra-pulpal temperature measurements were performed. The obtained data were analysed by means of ANOVA and Tukey`s test (alpha = 0.05). Results: In the demineralization solutions the groups L11F and GF presented significantly lower means of calcium and phosphorous losses than the control group; and in L11F means were significantly lower than in the fluoride group. Both irradiation parameters tested caused intrapulpal temperature increase below 2 degrees C. Conclusion: It can be concluded that under the conditions of this study, CO(2) laser irradiation (10.6 mu m) with 11J/cm(2) (540 mJ and 10 Hz) of fluoride treated dentine surfaces decreases the loss of calcium and phosphorous in the demineralization process and does not cause excessive temperature increase inside the pulp chamber. (C) 2010 Elsevier Ltd. All rights reserved.
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Objectives: The aim of this study was to test the effect of adhesive temperature on the bond strength to dentin (mu TBS) and silver nitrate uptake (SNU) of an ethanol/water (Adper Single Bond 2 [SB]) and an acetone-based (Prime&Bond 2.1 [PB]) etch-and-rinse adhesive system. Methods: The bottles of each adhesive were kept in various temperatures (5 degrees C, 20 degrees C, 37 degrees C and 50 degrees C) for 1 h previously to its application in the occlusal demineralized dentin of 40 molars. Bonded sticks (0.8 mm(2)) were tested in tension (0.5 mm/min) immediately (IM) or after 6 months (6 M) of water storage. Two bonded sticks from each hemi-tooth were immersed in silver nitrate and analyzed by SEM. Data were analyzed by two-way repeated measures ANOVA and Tukey`s test (alpha = 0.05). Results: No significant difference in mu TBS was detected for both adhesives at 5 degrees C and 20 degrees C. The highest bond strength for PB was observed in the 37 degrees C group while for SB it was in the 50 degrees C. Significant reductions of bond strengths were observed for PB at 37 degrees C and SB at 50 degrees C after 6 M of water storage. Silver nitrate deposition was seen in all hybrid layers, irrespective of the group. Lower silver nitrate deposition (water trees) in the adhesive layer was seen for PB and SB at higher temperatures. Conclusions: The heating or refrigeration of the adhesives did not improve their resin-dentin bond resistance to water degradation over time. (C) 2009 Elsevier Ltd. All rights reserved.
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Purpose: The objective of this study was to verify the influence of test environment on the flexural strength of dental porcelains with distinct microstructures. Material and Methods: Disk-shaped specimens from three dental porcelains with distinct leucite content (VM: zero; CE: 12; NS: 22 vol%) were manufactured and tested for biaxial flexural strength in air and immersed in artificial saliva. The results were analyzed by means of two-way ANOVA and Tukey`s test (alpha = 0.05). Results: The flexural strength (MPa) obtained for ambient air and artificial saliva environments, respectively, were: 110.0 +/- 16.0 and 81.5 +/- 10.8 for VM; 51.9 +/- 4.0 and 42.0 +/- 4.7 for CE; 72.0 +/- 11.5 and 63.6 +/- 5.8 for NS. A numerical decrease in the mean flexural strength was observed for all groups when specimens were tested under artificial saliva; however, the difference was only statistically significant for VM. Conclusions: The results indicate that the effect of water immersion on the flexural strength of dental porcelains varies according to their leucite content, as only the material without leucite in its microstructure (VM) showed significant strength degradation when tested under water.
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Objectives: To evaluate the influence of two surface sealants (BisCover/Single Bond) and three application techniques (unsealed/conventional/co-polymerization) on the roughness of two composites (Filtek Z250/Z350) after the toothbrushing test. Methods: Seventy-two rectangular specimens (5 mm x 10 mm x 3 mm) were fabricated and assigned into 12 groups (n = 6). Each sample was subjected to three random roughness readings at baseline, after 100,000 (intermediate), and 200,000 (final) toothbrushing strokes. Roughness (R) at each stage was obtained by the arithmetic mean of the reading of each specimen. Sealant removal was qualitatively examined (optical microscope) and classified into scores (0-3). Data were analyzed by Student`s paired t-test, two-way ANOVA/Tukey`s test, and by Wilcoxon, Kruskal-Wallis and Miller`s test (alpha = 0.05). Results: Z250 groups at baseline did not differ statistically from each other. Unsealed Z350 at baseline had lower R values. All the unsealed groups presented gradual decrease in R from baseline to final brushing. From baseline to the inter-mediate stage, Z250 co-polymerized groups presented a significant reduction in R (score 3). Conventionally sealed groups had no significant changes in R (scores 2-0.8). From baseline to the intermediate stage, the conventionally sealed Z350 Single Bond group had an increase in R (score 1.5). In the final stage, all the conventionally sealed groups presented a reduction in R (scores 0.7-0). Co-polymerized Single Bond groups had a significant reduction in R (scores 2.5-2.7), and co-polymerized BisCover groups an increase in R (scores 2.8-3). Conclusions: At any brushing stage, sealed composites presented superior performance when compared with unsealed composites. (C) 2009 Elsevier Ltd. All rights reserved.
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Objective: To evaluate whether the type of cola drink (regular or diet) could influence the wear of enamel subjected to erosion followed by brushing abrasion, Method and !Materials: Ten volunteers wore intraoral devices that each had eight bovine enamel blocks divided into four groups; ER, erosion with regular cola; EAR, erosion with regular cola plus abrasion; EL, erosion with light cola; and EAL, erosion with light cola plus abrasion, Each day for 1 week, half of each device was immersed in regular cola for 5 minutes, Then, two blocks were brushed using a fluoridated toothpaste and electric toothbrush for 30 seconds four times daily, Immediately after, the other half of the device was subjected to the same procedure using a light cola, The pH, calcium, phosphorus, and fluoride concentrations of the colas were analyzed using standard procedures, Enamel alterations were measured by profilometry. Data were tested using two-way ANOVA and Bonferroni test (P < .05), Results: Regarding chemical characteristics, light cola presented pH 3.0, 13.7 mg Ca/L, 15.5 mg P/L, and 0.31 mg F/L, while regular cola had pH 2.6, 32.1 mg Ca/L, 1:8.1 mg P/L, and 0.26 mg F/L, The light cola promoted less enamel loss (EL, 0.36 pm; EAL, 0.39 pm) than its regular counterpart (ER, 0.72 pm; EAR, 0.95 pm) for both conditions, There was not a significant difference (P > .05) between erosion and erosion plus abrasion for light cola, However, for regular cola, erosion plus abrasion resulted in higher enamel loss than erosion alone,.nclusion: The data suggest that light cola promoted less enamel wear even when erosion was followed by brushing abrasion, (Quintessence Int 2011;42:xxx-xx)()
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Purpose: This study evaluated the effect of different microwave polymerization cycles on the color changes of a microwave-processed denture base resin after accelerated aging and immersion in beverages. Materials and Methods: Specimens of light pink acrylic resin were divided into three groups according to polymerization cycle: (A) 500 W for 3 minutes, (B) 90 W for 13 minutes + 500 W for 90 seconds, and (C) 320 W for 3 minutes + 0 W for 4 minutes + 720 W for 3 minutes. Control groups were a heat-processed acrylic resin (T) and a chemically activated denture repair resin (Q). Eight specimens per group were aged in an artificial aging chamber and evaluated at 20, 192, and 384 hours. Another series of 40 specimens per group were immersed in water, coffee, tea, cola, or red wine and evaluated at 1, 12, and 36 days. Color was measured by a spectrophotometer before and after aging or immersion. Color changes (Delta E) were analyzed by ANOVA/Bonferroni t-test (alpha = 0.05). Results: Mean Delta E (+/- SD) after 384 hours of accelerated aging were (A) 2.51 +/- 0.50; (B) 3.16 +/- 1.09; (C) 2.89 +/- 1.06; (T) 2.64 +/- 0.34; and (Q) 9.03 +/- 0.40. Group Q had a significantly higher Delta E than the other groups. Color changes of immersed specimens were significantly influenced by solutions and time, but the five groups showed similar values. Mean Delta E at 36 days were (water) 1.4 +/- 0.8; (coffee) 1.3 +/- 0.6; (tea) 1.7 +/- 0.5; (cola) 1.4 +/- 0.7; and (red wine) 10.2 +/- 2.7. Results were similar among the five test groups. Conclusions: Color changes of the microwave-polymerized denture base resin tested were not affected by different polymerization cycles after accelerated aging or immersion in beverages. These changes were similar to the conventional heat-polymerized acrylic resin test, but lower than the repair resin after accelerated aging.
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Objectives: (1) To establish test performance measures for Transient Evoked Otoacoustic Emission testing of 6-year-old children in a school setting; (2) To investigate whether Transient Evoked Otoacoustic Emission testing provides a more accurate and effective alternative to a pure tone screening plus tympanometry protocol. Methods: Pure tone screening, tympanometry and transient evoked otoacoustic emission data were collected from 940 subjects (1880 ears), with a mean age of 6.2 years. Subjects were tested in non-sound-treated rooms within 22 schools. Receiver operating characteristics curves along with specificity, sensitivity, accuracy and efficiency values were determined for a variety of transient evoked otoacoustic emission/pure tone screening/tympanometry comparisons. Results: The Transient Evoked Otoacoustic Emission failure rate for the group was 20.3%. The failure rate for pure tone screening was found to be 8.9%, whilst 18.6% of subjects failed a protocol consisting of combined pure tone screening and tympanometry results. In essence, findings from the comparison of overall Transient Evoked Otoacoustic Emission pass/fail with overall pure tone screening pass/fail suggested that use of a modified Rhode Island Hearing Assessment Project criterion would result in a very high probability that a child with a pass result has normal hearing (true negative). However, the hit rate was only moderate. Selection of a signal-to-noise ratio (SNR) criterion set at greater than or equal to 1 dB appeared to provide the best test performance measures for the range of SNR values investigated. Test performance measures generally declined when tympanometry results were included, with the exception of lower false alarm rates and higher positive predictive values. The exclusion of low frequency data from the Transient Evoked Otoacoustic Emission SNR versus pure tone screening analysis resulted in improved performance measures. Conclusions: The present study poses several implications for the clinical implementation of Transient Evoked Otoacoustic Emission screening for entry level school children. Transient Evoked Otoacoustic Emission pass/fail criteria will require revision. The findings of the current investigation offer support to the possible replacement of pure tone screening with Transient Evoked Otoacoustic Emission testing for 6-year-old children. However, they do not suggest the replacement of the pure tone screening plus tympanometry battery. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.
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The insulin hypoglycemia test (IHT) is widely regarded as the 'gold standard' for dynamic stimulation of the hypothalamic-pituitary-adrenal (HPA) axis. This study aimed to investigate the temporal relationship between a rapid decrease in plasma glucose and the corresponding rise in plasma adenocorticotropic hormone (ACTH), and to assess the reproducibility of hormone responses to hypoglycemia in normal humans. Ten normal subjects underwent IHTs, using an insulin dose of 0.15 U/kg. Of these, eight had a second IHT (IHT2) and three went on to a third test (IHT3). Plasma ACTH and cortisol were measured at 15-min intervals and, additionally, in four IHT2s and the three IHT3s, ACTH was measured at 2.5- or 5-min intervals. Mean glucose nadirs and mean ACTH and cortisol responses were not significantly different between IHT1, IHT2 and IHT3. Combined data from all 21 tests showed the magnitude of the cortisol responses, but not the ACTH responses, correlated significantly with the depth and duration of hypoglycemia. All subjects achieved glucose concentrations of of less than or equal to 1.6 mmol/l before any detectable rise in ACTH occurred. In the seven tests performed with frequent sampling, an ACTH rise never preceeded the glucose nadir, but occurred at the nadir, or up to 15 min after. On repeat testing, peak ACTH levels varied markedly within individuals, whereas peak cortisol levels were more reproducible (mean coefficient of variation 7%). In conclusion, hypoglycemia of less than or equal to 1.6 mmol/l was sufficient to cause stimulation of the HPA axis in all 21 IHTs conducted in normal subjects. Nonetheless; our data cannot reveal whether higher glucose nadirs would stimulate increased HPA axis activity in all subjects. Overall, the cortisol response to hypoglycemia is more reproducible than the ACTH response but, in an individual subject, the difference in peak cortisol between two IHTs may exceed 100 nmol/l.