972 resultados para ZrO(2)center dot nH(2)O nanoparticles


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Ticlopidine hydrochloride (TICLID (R)) is a platelet antiaggregating agent whose use as a potent antithrombotic pharmaceutical ingredient is widespread, even though this drug has not been well characterized in the solid state. Only the crystal phase used for drug product manufacturing is known. Here, a new polymorph of ticlopidine hydrochloride was discovered and its structure was determined. While the antecedent polymorph crystallizes in the triclinic space group P (1) over bar, the new crystal phase was solved in the monoclinic space group P2(1)/c. Both polymorphs crystallize as racemic mixtures of enantiomeric (ticlopidine)(+) cations. Detailed geometrical and packing comparisons between the crystal structures of the two polymorphs have allowed us to understand how different supramolecular architectures are assembled. It was feasible to conclude that the main difference between the two polymorphs is a rotation of about 120 degrees on the bridging bond between the thienopyridine and o-chlorobenzyl moieties. The differential o-chlorobenzyl conformation is related to changeable patterns of weak intermolecular contacts involving this moiety, such as edge-to-face Cl center dot center dot center dot pi and C-H center dot center dot center dot pi interactions in the new polymorph and face-to-face pi center dot center dot center dot pi contacts in the triclinic crystal phase, leading to a symmetry increase in the ticlopidine hydrochloride solid state form described for the first time in this study. Other conformational features are slightly different between the two polymorphs, such as the thienopyridine puckerings and the o-chlorophenyl orientations. These conformational characteristics were also correlated to the crystal packing patterns.

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The title compound [systematic name: 3 beta-lup-20(29)-en-3-ol], C(30)H(50)O, was isolated from the leaves of Garcinia brasiliensis (common name: bacupari; a member of the Guttiferae family) and has been shown to have many useful medicinal and biological properties. The lupeol molecule consists of four six-membered rings (adopting chair conformations) and one five-membered ring (with an envelope conformation), all fused in trans fashion. Lupeol is isomorphic with the pentacyclic triterpene 3 beta,30-dihydroxylup-20(29)-ene, which differs from lupeol due to the presence of an additional hydroxy group. The crystal packing is stabilized by van der Waals interactions and intermolecular O-H center dot center dot center dot O hydrogen bonds, giving rise to an infinite helical chain along the c axis.

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center dot Dynamic resistance exercise promotes a sizeable increase in blood pressure during its execution in non medicated hypertensives. WHAT THIS STUDY ADDS center dot Atenolol not only decreases blood pressure level but also mitigates the increase of blood pressure during dynamic resistance exercise in hypertensive patients. An increase in blood pressure during resistance exercise might be at least in part attributed to an increase in cardiac output. AIMS This study was conducted to determine whether atenolol was able to decrease BP level and mitigate BP increase during dynamic resistance exercise performed at three different intensities in hypertensives. METHODS Ten essential hypertensives (systolic/diastolic BP between 140/90 and 160/105 mmHg) were blindly studied after 6 weeks of placebo and atenolol. In each phase, volunteers executed, in a random order, three protocols of knee-extension exercises to fatigue: (i) one set at 100% of 1 RM; (ii) three sets at 80% of 1 RM; and (iii) three sets at 40% of 1 RM. Intra-arterial radial blood pressure was measured throughout the protocols. RESULTS Atenolol decreased systolic BP maximum values achieved during the three exercise protocols (100% = 186 +/- 4 vs. 215 +/- 7, 80% = 224 +/- 7 vs. 247 +/- 9 and 40% = 223 +/- 7 vs. 252 +/- 16 mmHg, P < 0.05). Atenolol also mitigated an increase in systolic BP in the first set of exercises (100% = +38 +/- 5 vs. +54 +/- 9; 80% = +68 +/- 11 vs. +84 +/- 13 and 40% = +69 +/- 7 vs. +84 +/- 14, mmHg, P < 0.05). Atenolol decreased diastolic BP values and mitigated its increase during exercise performed at 100% of 1 RM (126 +/- 6 vs. 145 +/- 6 and +41 +/- 6 vs. +52 +/- 6, mmHg, P < 0.05), but not at the other exercise intensities. CONCLUSIONS Atenolol was effective in both reducing systolic BP maximum values and mitigating BP increase during resistance exercise performed at different intensities in hypertensive subjects.

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Aims. The aims of this study were to assess the internal reliability (internal consistency), construct validity, sensitivity and ceiling and floor effects of the Brazilian-Portuguese version of the Impact of Event Scale (IES). Design. Methodological research design. Method. The Brazilian-Portuguese version of the IES was applied to a group of 91 burned patients at three times: the first week after the burn injury (time one), between the fourth and the sixth months (time two) and between the ninth and the 12th months (time three). The internal consistency, construct validity (convergent and dimensionality), sensitivity and ceiling and floor effects were tested. Results. Cronbach`s alpha coefficients showed high internal consistency for the total scale (0 center dot 87) and for the domains intrusive thoughts (0 center dot 87) and avoidance responses (0 center dot 76). During the hospitalisation (time one), the scale showed low and positive correlations with pain measures immediately before (r = 0 center dot 22; p < 0 center dot 05) and immediately after baths and dressings (r = 0 center dot 21; p < 0 center dot 05). After the discharge, we found strong and negative correlations with self-esteem (r = -0 center dot 52; p < 0 center dot 01), strong and positive with depression (r = 0 center dot 63; p < 0 center dot 01) and low and negative with the Bodily pain (r = -0 center dot 24; p < 0 center dot 05), Social functioning (r = -0 center dot 34; p < 0 center dot 01) and Mental health (r = -0 center dot 27; p < 0 center dot 05) domains of the SF-36 at time two. Regarding the sensitivity, no statistically significant differences were observed between mean scale scores according to burned body surface (p = 0 center dot 21). The floor effect was observed in most of the IES items. Conclusion. The adapted version of the scale showed to be reliable and valid to assess postburn reactions on the impact of the event in the group of patients under analysis. Relevance to clinical practice. The Impact of Event Scale can be used in research and clinical practice to assess nursing interventions aimed at decreasing stress during rehabilitation.

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The effects of copper sprays on annual and polyetic progress of citrus canker, caused by Xanthomonas citri subsp. citri, in the presence of the Asian citrus leafminer (Phyllocnistis citrella), were evaluated in a study conducted in a commercial orchard in northwest Parana state, Brazil, where citrus canker is endemic. Nonlinear monomolecular, logistic and Gompertz models were fitted to monthly disease incidence data (proportion of leaves with symptoms) for each treatment for three seasons. The logistic model provided the best estimate of disease progress for all years and treatments evaluated and logistic parameter estimates were used to describe polyetic disease dynamics. Although citrus canker incidence increased during each of the seasons studied, it decreased over the whole study period, more so in copper-treated trees than in water-sprayed controls. Copper treatment reduced disease incidence compared with controls in every year, especially 2004-2005, when incidence was ca. 10-fold higher in controls than in treated plots (estimated asymptote values 0 center dot 82 and 0 center dot 07, respectively). Copper treatment also reduced estimated initial disease incidence and epidemic growth rates every year.

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Objectives: To evaluate biomarkers of endothelial dysfunction and oxidative stress in glucose intolerance (GI) compared to overt diabetes (DM2). Design and methods: 140 volunteers including 96 with DM2, 32 with GI and 12 controls (C) were Studied. NO metabolites, NO synthase inhibitors. thiols and N-acetyl-beta-glucosaminidase (NAGase) activity were analyzed by chemiluminescence, capillary electrophoresis, ELISA and colorimetric assay, respectively. Results: (center dot)NO metabolites were higher in GI (NOx: P=0.03 S-nitrosothiols: p=0.001) and DM2 (p=0.006; p=0.0006) groups in relation to group C, while nitrotyrosine was higher only in the DM2 group in comparison 10 the other groups. NAGase activity was elevated in GI (p=0.003) and DM2 (p=0.0004) groups in relation to group C, as well as, ADMA (p=0.01: p=0.003) and GSSG (p=0.01 p=0.002). Conclusions: (center dot)NO metabolites. (center dot)NO synthase inhibitors. thiols and NAGase are biomarkers Suitable to indicate endothelial dysfunction and oxidative stress in the early stages of impaired response to insulin. (c) 2008 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

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The objective of this work was to characterize exotic fruits (cambuci, araca-boi, camu-camu, jaracatia, araca) and commercial frozen pulps (araca, cambuci, umbu, coquinho, pana, native passion fruit, cagaita) from Brazil in relation to their bioactive compounds contents and antioxidant capacity. Camu-camu (Myrciaria dubia) presented the highest vitamin C and total phenolics contents (397 and 1797 mg/100 g f.w., respectively) and the highest DPPH(center dot) scavenging capacity. Coquinho (Butia capitata) also showed a significant vitamin C content (43 mg/100 g f.w.). Among the commercial frozen pulps, cagaita presented the higher DPPH scavenging activity and inhibition of beta-carotene bleaching. A good correlation between total phenols and DPPH scavenging activity was found for fruits (r = 0.997) and commercial frozen pulps (r = 0.738). However, no correlation was found for total phenols and inhibition of beta-carotene bleaching. Quercetin and kaempferol derivatives were the main flavonoids present in all samples and cyanidin derivatives were detected only in camu-camu. Camu-camu and araca (Psidium guineensis) showed the highest total ellagic acid contents (48 and 63.5 mg/100 g f.w.). All commercial frozen pulps presented lower contents of bioactive compounds and antioxidant capacity than their respective fruits. According to our results, camu-camu and araca might be sources of bioactive compounds.

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This paper reports theoretical and experimental studies of gas-phase fragmentation reactions of four naturally occurring isoflavones. The samples were analyzed in negative ion mode by direct infusion in ESI-QqQ, ESI-QqTOF and ESI-Orbitrap systems. The MS/MS and MS(n) spectra are in agreement with the fragmentation proposals and high-resolution analyses have confirmed the formulae for each ion observed. As expected, compounds with methoxyl aromatic substitution have showed a radical elimination of center dot CH(3) as the main fragmentation pathway. A second radical loss (center dot H) occurs as previously observed for compounds which exhibit a previous homolytic center dot CH(3) cleavage (radical anion) and involves radical resonance to stabilize the anion formed. However, in this study we suggest another mechanism for the formation of the main ions, on the basis of the enthalpies for each species. Compounds without methoxy substituent dissociate at the highest energies and exhibit the deprotonated molecule as the most intense ion. Finally, energy-resolved experiments were carried out to give more details about the gas-phase dissociation reaction of the isoflavones and the results are in agreement with the theoretical approaches. Copyright (C) 2011 John Wiley & Sons, Ltd.

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The beta-carbolines 1-methyl-9H-pyrido [3,4-b]indole and 9H-pyrido[3,4b]indole have been implicated as having causative roles in a number of human diseases, such as Parkinson`s disease and cancer. As they can be formed during the heating of protein-rich food, a number of analytical methodologies have been proposed for their detection and quantification in foodstuff For this purpose, LC-MS and LC-MS/MS have emerged as the most specific analytical methods, and the quantification is based on the occurrence of unusual ions, such as [M+H-(H(center dot))](+) and [M + H-2H](+). In this study, we have investigated the formation of these ions by accurate-mass electrospray MS/MS and demonstrated that these ions are formed from gas-phase ion-molecule reactions between water vapor present in the collision cell and the protonated molecule of 1-methyl-9H-pyrido [3,4-b]indole and 9H-pyrido[3,4b]indole. Although this reaction has been previously described for heterocyclic amine ions, it has been overlooked in the most of recent LC-MS and LC-MS/MS studies, and no complete data of the fragmentation are reported. Our results demonstrate that additional attention should be given with respect to eliminating water vapor residues in the mass spectrometer when analysis of beta-carbolines is performed, as this residue may affect the reliability in the results of quantification.

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Background Brazil has one of the highest stroke mortality rates in the world, these rates are most endemic in the poor. We verified the prevalence of stroke in a deprived neighbourhood in the city of Sao Paulo, Brazil and compared it with other surveys worldwide. Methods A questionnaire with six questions concerning limb and facial weakness, articulation, sensory disturbances, impaired vision, and past diagnosis of stroke was completed door-to-door in a well-defined area of 15 000 people. Questionnaires were considered positive when a participant answered two or more questions about stroke symptoms or the presence of stroke being confirmed by a physician, or at least three questions in the positive, even if not confirmed by a doctor. Results Of the 4496 individuals over 35-years old living in the area, 243 initially screened positive for stroke. The age-adjusted prevalence rate for men was 4 center dot 6% (95% confidence interval 3 center dot 5-5 center dot 7). For women, the prevalence rate was 6 center dot 5% (95% confidence interval 5 center dot 5-7 center dot 5); when considering only one question, the rate was 4 center dot 8% (95% confidence interval 3 center dot 9-5 center dot 7). The most commonly reported symptoms were limb weakness and sensory disturbances. Hypertension and heart disease were the conditions most commonly associated with previous stroke. Conclusion Stroke prevalence rates were higher in this poor neighbourhood compared with other surveys.

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Methods: Six adult mixed breed dogs (two males and four females) weighing 7 to 14 kg (10 center dot 5 +/- 1 center dot 5 kg) and aged two to five years were used. Each dog received both treatments in random order: levobupivacaine alone (LBA; n=6) or levobupivacaine plus hyaluronidase (LBH; n=6) administered in the lumbosacral epidural space. Systemic effects, spread and duration of anaesthesia and motor block were determined before treatment and at predetermined intervals. Results: The duration of local anaesthesia was 90 +/- 10 minutes (P=0 center dot 001) for LBH treatment and 150 +/- 15 minutes for LBA treatment. In the LBH treatment, anaesthesia reached the T12 to T13 dermatome and in the LBA treatment it reached the T11 to T12 dermatome in all animals in 5 and 15 minutes, respectively. Complete motor blockade was 75 +/- 12 minutes (P=0 center dot 01) and 120 +/- 15 minutes for LBH and LBA treatments, respectively. Clinical Significance: Hyaluronidase added to levobupivacaine significantly shortens the duration of epidural anaesthesia with the same dermatome spread into the epidural space in dogs.

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P>Background The nonclassical human leucocyte antigen (HLA)-G molecule has been well recognized as a tolerogenic molecule and few studies have evaluated the role of the molecule in inflammatory cutaneous autoimmune diseases. Objectives To evaluate the expression of HLA-G in skin specimens of patients with psoriasis and to analyse its correlation with epidemiological and clinical variables. Methods Thirty untreated patients with psoriasis and 32 healthy individuals were enrolled. Immunohistochemistry was applied to identify HLA-G expression in formalin-fixed paraffin-embedded cutaneous skin biopsies. Results Soluble and membrane-bound HLA-G expression was detected in 30 (90%) of the skin specimens from patients presenting clinical and histopathological features of psoriasis. Although infiltrating lymphomononuclear cells of the dermis exhibited HLA-G expression, the epidermis was primarily targeted. HLA-G expression was also observed in 27% (three of 11) of the specimens that exhibited no clinical and histopathological features of psoriasis (nonaffected areas). In contrast, skin specimens obtained from healthy individuals exhibited no HLA-G expression (P < 0 center dot 0001). The intensity of HLA-G expression was not associated with type I/II psoriasis, Psoriasis Area and Severity Index score or clinical forms. Conclusions As the HLA-G molecule was consistently expressed in affected and, to a lesser extent, in nonaffected areas of untreated patients with psoriasis, irrespective of the severity of the clinical variants, one may hypothesize that the presence of HLA-G may be responsible, at least in part, for the regulation of autoimmune effector cells.

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center dot Citalopram (CITA) pharmacokinetics are enantioselective in healthy volunteers and the metabolism of (+)-(S)-CITA to (+)-(S)-DCITA is dependent on CYP2C19. Omeprazole is a potent CYP2C19 inhibitor. WHAT THIS STUDY ADDS center dot This study indicates that omeprazole induces a loss of enantioselectivity in the CITA pharmacokinetics because of the selective inhibition of (+)-(S)-CITA metabolism. AIM The study assessed the influence of omeprazole on the kinetic disposition of the (+)-(S)-citalopram (CITA) and (-)-(R)-CITA enantiomers in healthy volunteers. METHODS In a cross-over study, healthy volunteers (n = 9) phenotyped as extensive metabolizers of CYP2C19 and CYP2D6 and with an oral midazolam clearance ranging from 10.9 to 149.3 ml min-1 kg-1 received a single dose of racemic CITA (20 mg orally) in combination or not with omeprazole (20 mg day-1 for 18 days). Serial blood samples were collected up to 240 h after CITA administration. CITA and demethylcitalopram (DCITA) enantiomers were analyzed by LC-MS/MS using a Chiralcel (R) OD-R column. RESULTS The kinetic disposition of CITA was enantioselective in the absence of treatment with omeprazole, with the observation of a greater proportion of plasma (-)-(R)-CITA [AUC S : R ratio of 0.53 (95% CI 0.41, 0.66) for CITA and 1.08 (95% CI 0.80, 1.76) for DCITA] than (+)-(S)-CITA. Racemic CITA administration to healthy volunteers in combination with omeprazole showed a loss of enantioselectivity in CITA pharmacokinetics with an increase of approximately 120% in plasma (+)-(S)-CITA concentrations [AUC S : R ratio of 0.95 (95% CI 0.72, 1.10) for CITA and 0.95 (95% CI 0.44, 1.72) for DCITA]. CONCLUSIONS The administration of multiple doses of omeprazole preferentially inhibited (+)-(S)-CITA metabolism in healthy volunteers. Although omeprazole increased plasma concentrations of (+)-(S)-CITA by approximately 120%, it is difficult to evaluate the clinical outcome because the range of plasma CITA concentrations related to maximum efficacy and minimum risk of adverse effects has not been established.

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P>The purpose of this study was to evaluate the influence of age on the electromyographic activity of masticatory muscles. All volunteers were Brazilian, fully dentate (except for Group I - mixed dentition), Caucasian, aged 7-80, and divided into five groups: I (7-12 years), II (13-20 years), III (21-40 years), IV (41-60 years) and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided with respect to gender (20 M/20 F). Surface electromyographic records of masticatory muscles were obtained at rest and during maximal voluntary contraction, right and left laterality, maximal jaw protrusion and maximal clenching in the intercuspal position. Statistically significant differences (P < 0 center dot 05) were found in all clinical conditions among the different age groups. Considerably different patterns of muscle activation were found across ages, with greater electromyographic activity in children and youth, and decreasing from adults to aged people.

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P>The determination of normal parameters is an important procedure in the evaluation of the stomatognathic system. We used the surface electromyography standardization protocol described by Ferrario et al. (J Oral Rehabil. 2000;27:33-40, 2006;33:341) to determine reference values of the electromyographic standardized indices for the assessment of muscular symmetry (left and right side, percentage overlapping coefficient, POC), potential lateral displacing components (unbalanced contractile activities of contralateral masseter and temporalis muscles, TC), relative activity (most prevalent pair of masticatory muscles, ATTIV) and total activity (integrated areas of the electromyographic potentials over time, IMPACT) in healthy Brazilian young adults, and the relevant data reproducibility. Electromyography of the right and left masseter and temporalis muscles was performed during maximum teeth clenching in 20 healthy subjects (10 women and 10 men, mean age 23 years, s.d. 3), free from periodontal problems, temporomandibular disorders, oro-facial myofunctional disorder, and with full permanent dentition (28 teeth at least). Data reproducibility was computed for 75% of the sample. The values obtained were POC Temporal (88 center dot 11 +/- 1 center dot 45%), POC masseter (87 center dot 11 +/- 1 center dot 60%), TC (8 center dot 79 +/- 1 center dot 20%), ATTIV (-0 center dot 33 +/- 9 center dot 65%) and IMPACT (110 center dot 40 +/- 23 center dot 69 mu V/mu V center dot s %). There were no statistical differences between test and retest values (P > 0 center dot 05). The Technical Errors of Measurement (TEM) for 50% of subjects assessed during the same session were 1 center dot 5, 1 center dot 39, 1 center dot 06, 3 center dot 83 and 10 center dot 04. For 25% of the subjects assessed after a 6-month interval, the TEM were 0 center dot 80, 1 center dot 03, 0 center dot 73, 12 center dot 70 and 19 center dot 10. For all indices, there was good reproducibility. These electromyographic indices could be used in the assessment of patients with stomatognathic dysfunction.