532 resultados para Fixed effect


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Purpose: To compare the efficacy and tolerability of the fixed combination of timolol maleate 0.5%/brimonidine tartrate 0.2% versus fixed combination of timolol maleate 0.5%/dorzolamide 2% in patients with elevated intraocular pressure (IOP) over 8 weeks. Patients and Methods: This 8-week, multicentric. interventional, randomized, open-label, parallel group study was conducted Lit 4 centers in Brazil and 1 center in Argentina. Patients with open-angle glaucoma or ocular hypertension were randomized to receive bilaterally fixed combination of brimonidine/timolol maleate 0.5% or fixed combination of dorzolamide 2%/timolol 0.5% twice daily at 8:00 AM and 8:00 PM. A modified diurnal tension curve (8:00 AM 10:30 AM, 02:00 PM, and 4:00 PM) followed by the water drinking test (WDT), which estimates IOP peak of diurnal tension curve, were performed in the baseline and week-8 visits. Adverse events data were recorded at each visit. Results: A total of 210 patients were randomized (brimonidine/timolol, n = 111; dorzolamide/timolol, n = 99). Mean baseline IOP was 23.43 +/- 3.22 mm Hg and 23.43 +/- 4.06 mm Hg in the patients treated with brimonidine/timolol and dorzolamide/timolol, respectively (P = 0.993). Mean diurnal IOP reduction after 8 weeks were 7.02 +/- 3.06 mm Hg and 6.91 +/- 3.67 mm Hg. respectively (P = 0.811). The adjusted difference between groups (analysis of covariance) Lit week 8 was not statistically significant (P = 0.847). Mean baseline WDT peak was 27.79 +/- 4.29 mm Hg in the brimonidine/timolol group and 27.68 +/- 5.46 mm Hg in the dorzolamide/timolol group. After 8 weeks of treatment, mean WDT peaks were 20.94 +/- 3.76 mm Hg (P < 0.001) and 20.98 +/- 4.19 (P < 0.001), respectively. The adjusted difference between groups (analysis of covariance) was not statistically significant (P = 0.469). No statistical difference in terms of adverse events was Found between groups. Conclusions: Both fixed combinations were capable of significantly reducing the mean diurnal IOP, mean diurnal peak, and mean WDT peak after 8 weeks of treatment. Also, both fixed combinations are well tolerated with few side effects.

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PURPOSE: To investigate the combined effects of ethanol and mitomycin C (MMC) application on the corneal stroma of rabbits that underwent photorefractive keratectomy (PRK). METHODS: Twenty-four rabbits (24 eyes) underwent PRK to correct -9.00 diopters of myopia. Twelve eyes had ethanol application before removing the epithelium and 12 eyes had the epithelium manually removed without ethanol, Eyes in both groups had topical MMC 0.02% application for 12 seconds immediately after excimer laser ablation. Twelve rabbits were sacrificed at two time points-4 hours and 4 weeks after surgery-and immunohistochemistry was performed with TUNEL assay, alpha-smooth muscle actin (alpha-SMA), and DAPI. RESULTS: More TUNEL-positive cells were observed in the ethanol-treated group compared to the mechanical debridement group at 4 hours after surgery (P<.01). No significant difference in alpha-SMA-positive cells was detected, between the two groups at 4 weeks after sugery. However, decreased keratocyte density in the anterior stroma was more pronounced in the ethanol-treated group compared to the mechanical debridement (P<.02). CONCLUSIONS: Ethanol application for epithelial removal during PRK seems to produce a synergistic effect with MMC, resulting in fewer keratocytes in the anterior stroma of rabbit corneas treated with MMC and ethanol than in corneas treated with MMC alone after PRK.

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Objective: To analyze the antiangiogenic effects of the selective cyclooxygenase-2 (COX-2) inhibitor parecoxib on the growth of endometrial implants in a rat model of peritoneal endometriosis. Design: Pharmacologic interventions in an experimental model of peritoneal endometriosis. Setting: Research laboratory in the Federal University of Rio de Janeiro. Animal(s): Twenty female Sprague-Dawley rats with experimentally induced endometriosis. Intervention(s): After implantation and establishment of autologous endometrium onto the peritoneum abdominal wall, rats were randomized into groups and treated with parecoxib or the vehicle by IM injection for 30 days. Main Outcome Measure(s): Vascular density, the expression of vascular endothelial growth factor (VEGF) and its receptor Flk-1, the distribution of activated macrophages, the expression of COX-2, and the prostaglandin concentration in the endometriotic lesions treated with parecoxib were analyzed. Result(s): The treatment significantly decreased the implant size, and histologic examination indicated mostly atrophy and regression. A reduction in microvessel density and in the number of macrophages, associated with decreased expression of VEGF and Flk-1, also were observed. The treatment group showed a low concentration of prostaglandin E(2). Conclusion(s): These results suggest that the use of COX-2 selective inhibitors could be effective to suppress the establishment and growth of endometriosis, partially through their antiangiogenic activity. (Fertil Steril (R) 2010; 93: 2674-9. (C) 2010 by American Society for Reproductive Medicine.)

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Objective: To analyze the effects of sildenafil citrate on clitoral blood flow and sexual response in postmenopausal women with orgasmic dysfunction. Method: In this randomized, double-blind, placebo-controlled trial 22 women received a 50-mg dose of sildenafil (n=11) or placebo (n=11) daily for 15 days. The Golombok Rust Inventory of Sexual Satisfaction (GRISS) was used for subjective evaluation of the sexual-response cycle. Clitoral blood flow was measured by color and pulse Doppler at baseline, after 1 hour of taking the first dose, and after 15 days of treatment. Results: Blood flow was significantly more improved in the sildenafit than in the placebo group (P<0.05), and a positive correlation between Doppler values and GRISS scores was noted in the sildenafil group after only 15 days of treatment. Conclusion: Sildenafil may improve clitoral blood flow and increase the GRISS scores in postmenopausal women with orgasmic dysfunction. (C) 2008 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

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Alcohol and tobacco consumption are well-recognized risk factors for head and neck cancer (HNC). Evidence suggests that genetic predisposition may also play a role. Only a few epidemiologic studies, however, have considered the relation between HNC risk and family history of HNC and other cancers. We pooled individual-level data across 12 case-control studies including 8,967 HNC cases and 13,627 controls. We obtained pooled odds ratios (OR) using fixed and random effect models and adjusting for potential confounding factors. All statistical tests were two-sided. A family history of HNC in first-degree relatives increased the risk of HNC (OR = 1.7, 95% confidence interval, CI, 1.2-2.3). The risk was higher when the affected relative was a sibling (OR = 2.2, 95% CI 1.6-3.1) rather than a parent (OR = 1.5, 95% CI 1.1-1.8) and for more distal HNC anatomic sites (hypopharynx and larynx). The risk was also higher, or limited to, in subjects exposed to tobacco. The OR rose to 7.2 (95% CI 5.5-9.5) among subjects with family history, who were alcohol and tobacco users. A weak but significant association (OR = 1.1, 95% CI 1.0-1.2) emerged for family history of other tobacco-related neoplasms, particularly with laryngeal cancer (OR = 1.3, 95% CI 1.1-1.5). No association was observed for family history of nontobacco-related neoplasms and the risk of HNC (OR = 1.0, 95% CI 0.9-1.1). Familial factors play a role in the etiology of HNC. In both subjects with and without family history of HNC, avoidance of tobacco and alcohol exposure may be the best way to avoid HNC. (C) 2008 Wiley-Liss, Inc,

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Background. - Tardive dyskinesia (TD) is a movement disorder observed after chronic neuroleptic treatment. Smoking is presumed to increase the prevalence of TD. The question of a cause-effect-relationship between smoking and TD, however, remains to be answered. Purpose of this study was to examine the correlation between the degree of smoking and the severity of TD with respect to differences caused by medication. Method. - We examined 60 patients suffering from schizophrenia and TD, We compared a clozapine-treated group With a group treated with typical neuroleptics. Movement disorders were assessed using the Abnormal-Involuntary-Movement-Scale and the technical device digital image processing, providing rater independent information on perioral movements. Results. - We found a strong correlation (.80 < r < .90, always p < .0001) between the degree of smoking and severity of TD. Repeated measurements revealed a positive correlation between changes in cigarette consumption and changes of the severity of TD (p < .0001). Analyses of covariance indicated a significant group-effect with a lower severity of TD in the clozapine-group compared to the typical-neuroleptics-group (p = .010). Interaction-analyses indicated a higher impact of smoking oil the severity of TD in the typical-neuroleptics-group compared to the clozapine-group (p = .033). Conclusion. - Concerning a possible cause-effect-relationship between smoking and TD, smoking is more of a general health hazard than neuroleptic exposure in terms of TD. (C) 2008 Elsevier Masson SAS. All rights reserved.

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In South America, visceral leishmaniasis is a zoonosis caused by the protozoan species Leishmania infantum (syn. L. chagasi) and is primarily transmitted through the bite of the female Lutzomyia longipalpis. Its main reservoir in urban areas is the dog. The application of control measures recommended by health agencies have not achieved significant results in reducing the incidence of human cases, and the lack of effective drugs to treat dogs resulted in the prohibition of this course of action in Brazil. Therefore, it is necessary to search new alternatives for the treatment of canine and human visceral leishmaniasis. The objectives of this study were to evaluate the in vitro effect of fractions from Aloe vera (aloe), Coriandrum sativum (coriander), and Ricinus communis (castor) on promastigotes and amastigotes of L. infantum and to analyze the toxicity against the murine monocytic cells RAW 264.7. To determine the viability of these substances on 50% parasites (IC50), we used a tetrazolium dye (MU) colorimetric assay (bromide 3-4.5-dimethylthiazol-2-yl-2,5-dephenyltetrazolium), and on amastigotes we performed an in situ ELISA. All fractions were effective against L. infantum promastigotes and did not differ from the positive control pentamidine (p > 0.05). However, the R. communis ethyl acetate and chloroform fractions, as well as the C. sativum methanol fraction, were the most effective against amastigotes and did not differ from the positive control amphotericin B (p > 0.05). The R. communis ethyl acetate fraction was the least toxic, presenting 83.5% viability of RAW 264.7 cells, which was similar to the results obtained with amphotericin B (p > 0.05). Based on these results, we intend to undertake in vivo studies with R. communis ethyl acetate fractions due the high effectiveness against amastigotes and promastigotes of L. infantum and the low cytotoxicity towards murine monocytic cells. (C) 2011 Elsevier B.V. All rights reserved.

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Anti-IgE, omalizumab, inhibits the allergen response in patients with asthma. This has not been directly related to changes in inflammatory conditions. We hypothesized that anti-IgE exerts its effects by reducing airway inflammation. To that end, the effect of anti-IgE on allergen-induced inflammation in bronchial biopsies in 25 patients with asthma was investigated in a randomized, double-blind, placebo-controlled study. Allergen challenge followed by a bronchoscopy at 24 h was performed at baseline and after 12 weeks of treatment with anti-IgE or placebo. Provocative concentration that causes a 20% fall in forced expiratory volume in 1 s (PC(20)) methacholine and induced sputum was performed at baseline, 8 and 12 weeks of treatment. Changes in the early and late responses to allergen, PC(20), inflammatory cells in biopsies and sputum were assessed. Both the early and late asthmatic responses were suppressed to 15.3% and 4.7% following anti-IgE treatment as compared with placebo (P < 0.002). This was paralleled by a decrease in eosinophil counts in sputum (4-0.5%) and postallergen biopsies (15-2 cells/0.1 mm(2)) (P < 0.03). Furthermore, biopsy IgE+ cells were significantly reduced between both the groups, whereas high-affinity IgE receptor and CD4+ cells were decreased within the anti-IgE group. There were no significant differences for PC(20) methacholine. The response to inhaled allergen in asthma is diminished by anti-IgE, which in bronchial mucosa is paralleled by a reduction in eosinophils and a decline in IgE-bearing cells postallergen without changing PC(20) methacholine. This suggests that the benefits of anti-IgE in asthma may be explained by a decrease in eosinophilic inflammation and IgE-bearing cells.

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Indomethacin administration in animals increases permeability of the small intestine, leading to inflammation that mimics Crohn`s disease. Nonsteroidal anti-inflammatory drugs increase the permeability of the intestinal epithelial barrier and should therefore be used with caution in patients with Crohn`s disease. We analyzed the protective effects of octreotide and the tumor necrosis factor-alpha inhibitor infliximab in a rat model of indomethacin-induced enterocolitis. Male Wistar rats received 20 mg of infliximab or 10 mu g of octreotide 24 h prior to injection with indomethacin. Intestinal permeability was analyzed using Cr-51-ethylenediaminetetraacetic acid clearance. No microscopic or macroscopic alterations were observed in the rats receiving infliximab or octreotide, both of which increased permeability (P < 0.001 versus controls). Our macroscopic and microscopic findings might be related to the low specificity of infliximab and suggest that cytokines affect the intestinal epithelial barrier, as evidenced by the protective effect that infliximab had on the permeability parameters evaluated.

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The aim of this study was to evaluate the effect of the pulsed ultrasound therapy (PUT) in stimulating myoregeneration and collagen deposition in an experimental model of lacerative gastrocnemius muscle lesion in 30 Wistar rats. Fifteen rats were treated (TG) daily with 1 MHz pulsed ultrasound (50%) at 0.57 W/cm(2) for 5 min, and 15 were control animals (CG). Muscle samples were analyzed on postoperative days 4, 7 and 14 through H&E, Picrosirius-polarization and immunohistochemistry for desmin. The lesions presented similar inflammatory responses in both treated and control groups. The areal fraction of fibrillar collagen was larger in the TG at 4 days post-operatively (17.53 +/- 6.2% vs 6.79 +/- 1.3%, p = 0.0491), 7 days (31.07 +/- 7.45% vs 12.57 +/- 3.6%, p = 0.0021) and 14 days (30.39 +/- 7.3% vs 19.13 +/- 3.51%, p = 0.0118); the areal fraction of myoblasts and myotubes was larger in the TG at 14 days after surgery (41.66 +/- 2.97% vs 34.83 +/- 3.08%, p = 0.025). Our data suggest that the PUT increases the differentiation of muscular lineage cells, what would favor tissue regeneration. On the other hand, it is also suggested that there is a larger deposition of collagenous fibers, what could mean worse functional performance. However, the percentage of fibers seems to have stabilized at day 7 in TG and kept increasing in CG. Furthermore, the collagen supramolecular organization achieved by the TG is also significant according to the Sirius red staining results. (C) 2008 Elsevier B.V. All rights reserved.

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In this study, the effect of phospholipase A2 (PLA2) derived from Crotalus durissus collilineatus was evaluated in vitro and in vivo on experimental cutaneous leishmaniasis. The promastigote and amastigote forms treated with PLA2 presented increased growth rate. In vivo studies showed that PLA2-treated Leishmania (Leishmania) amazonensis promastigotes increased the size of lesions in BALB/c mice, and histopathological analysis showed numerous necrotic regions presenting a higher density of polymorphonuclear, mononuclear, and amastigote cells. Additionally, infected macrophages treated with PLA2 were able to generate prostaglandin E2 (PGE2). Cytokine quantification showed that the supernatant from infected macrophages presented moderate and high amounts of IL-2 and IL-10, respectively. However, in PLA2-treated infected macrophages, suppression of IL-2 levels occurred, but not of IL-10 levels. Observation also revealed that both the supernatant and lysate of L. (L.) amazonensis promastigotes exhibited PLA2 activity, which, in the presence of dexamethasone, showed no reduction in their activities; while glucocorticoid maintained the ability of promastigote forms to infect macrophages, which presented values similar to controls. In conclusion, the results indicate that PLA2 may be a progression factor for cutaneous leishmaniasis, since the PLA2 effect suppressed IL-2 levels and generated PGE2, an inflammatory lipid mediator.

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Exposure to air pollution can elicit cardiovascular health effects. Children and unborn fetuses appear to be particularly vulnerable. However, the mechanisms involved in cardiovascular damage are poorly understood. It has been suggested that the oxidative stress generated by air pollution exposure triggers tissue injury. To investigate whether prenatal exposure can enhance oxidative stress in myocardium of adult animals, mice were placed in a clean chamber (CC, filtered urban air) and in a polluted chamber (PC, Sao Paulo city) during the gestational period and/or for 3 mo after birth, according to 4 protocols: control group-prenatal and postnatal life in CC; prenatal group-prenatal in PC and postnatal life in CC; postnatal group-prenatal in CC and postnatal life in PC; and pre-post group-prenatal and postnatal life in PC. As an indicator of oxidative stress, levels of lipid peroxidation in hearts were measured by malondialdehyde (MDA) quantification and by quantification of the myocardial immunoreactivity for 15-F2t-isoprostane. Ultrastructural studies were performed to detect cellular alterations related to oxidative stress. Concentration of MDA was significantly increased in postnatal (2.45 +/- 0.84 nmol/mg) and pre-post groups (3.84 +/- 1.39 nmol/mg) compared to the control group (0.31 +/- 0.10 nmol/mg) (p < .01). MDA values in the pre-post group were significantly increased compared to the prenatal group (0.71 +/- 0.15 nmol/mg) (p = .017). Myocardial isoprostane area fraction in the pre-post group was increased compared to other groups (p <= .01). Results show that ambient levels of air pollution elicit cardiac oxidative stress in adult mice, and that gestational exposure may enhance this effect.

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We studied the anisotropic aggregation of spherical latex particles dispersed in a lyotropic liquid crystal presenting three nematic phases; calamitic, biaxial, and discotic. We observed that in the nematic calamitic phase aggregates of latex particles are formed, which become larger and anisotropic in the vicinity of the transition to the discotic phase, due to a coalescence process. Such aggregates are weakly anisotropic and up to 50 mu m long and tend to align parallel to the director field. At the transition to the discotic phase, the aggregates dissociated and re-formed when the system was brought back to the calamitic phase. This shows that the aggregation is due to attractive and repulsive forces generated by the particular structure of the nematic phase. The surface-induced positional order was investigated by surface force apparatus experiments with the lyotropic system confined between mica surfaces, revealing the existence of a presmectic wetting layer around the surfaces and oscillating forces of increasing amplitude as the confinement thickness was decreased. We discuss the possible mechanisms responsible for the reversible aggregation of latex particles, and we propose that capillary condensation of the N(C) phase, induced by the confinement between the particles, could reduce or remove the gradient of order parameter, driving the transition of aggregates from solidlike to liquidlike and gaslike.

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Intense lifestyle modifications can change the high-density lipoprotein (HDL) cholesterol concentration. The aim of the present study was to analyze the early effects of short-term exercise training, without any specific diet, on the HDL cholesterol plasma levels and HDL functional characteristics in patients with the metabolic syndrome (MS). We studied 30 sedentary subjects, 20 with and 10 without the MS. The patients with the MS underwent moderate intensity exercise training for 3 months on bicycle ergometers. Blood was sampled before and after training for biochemical analysis, paraoxonase-1 activity, and HDL subfraction composition and antioxidative capacity. Lipid transfer to HDL was assayed in vitro using a labeled nanoemulsion as the lipid donor. At baseline, the MS group had greater triglyceride levels and a lower HDL cholesterol concentration and lower paraoxonase-1 activity than did the controls. Training decreased the plasma triglycerides but did not change the low-density lipoprotein or HDL cholesterol levels. Nonetheless, exercise training increased the HDL subfractions` antioxidative capacity and paraoxonase-1 activity. After training, the MS group had compositional changes in the smallest HDL subfractions associated with increased free cholesterol and cholesterol ester transfers to HDL, reaching normal values. In conclusion, the present investigation has added relevant information about the dissociation between the quantitative and qualitative aspects of HDL after short-term exercise training without any specific diet in those with the MS, highlighting the importance of evaluating the functional aspects of the lipoproteins, in addition to their plasma levels. (C) 2011 Elsevier Inc. All rights reserved. (Am J Cardiol 2011;107:1168-1172)

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Objective: To compare the volume of the hippocampus and parahippocampal gyrus in elderly individuals with and without depressive disorders, and to determine whether the volumes of these regions correlate with scores on memory tests. Method: Clinical and demographic differences, as well as differences in regional gray matter volumes, were assessed in 48 elderly patients with depressive disorders and 31 control subjects. Brain (structural MRI) scans were processed using statistical parametric mapping and voxel-based morphometry. Cognitive tests were administered to subjects in both groups. Results: There were no between-group gray matter volume differences in the hippocampus or parahippocampal gyrus. In the elderly depressed group only, the volume of the left parahippocampal gyrus correlated with scores on the delayed naming portion of the visual verbal learning test. There were also significant direct correlations in depressed subjects between the volumes of the left hippocampus, right and left parahippocampal gyrus and immediate recall scores on verbal episodic memory tests and visual learning tests. In the control group, there were direct correlations only between overall cognitive performance (as assessed with the MMSE) and the volume of right hippocampus, and between the total score on the visual verbal learning test and the volume of the right and left parahippocampal gyrus. Conclusions: These findings highlight different patterns of relationship between cognitive performance and volumes of medial temporal structures in depressed individuals and healthy elderly subjects. The direct correlation between delayed visual verbal memory recall scores with left parahippocampal volumes specifically in elderly depressed individuals provides support to the view that depression in elderly populations may be a risk factor for dementia. (C) 2009 Elsevier Inc. All rights reserved.