999 resultados para Whittle, Andrea
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We aimed to investigate the vascular effects of hyperhomocysteinemia (HHcy) on carotid arteries from young and adult rats. With this purpose young and adult rats received a solution of DL-homocysteine-thiolactone (1 g/kg body weight/day) in the drinking water for 7, 14 and 28 days. Increase on plasma homocysteine occurred in young and adult rats treated with DL-homocysteine-thiolactone in all periods. Vascular reactivity experiments using standard muscle bath procedures showed that HHcy enhanced the contractile response of endothelium-intact, carotid rings to phenylephrine in both young and adult rats. However, in young rats, the increased phenylephrine-induced contraction was observed after hyperhomocysteinemia for 14 and 28 days, whereas in adult rats this response was already apparent after 7 day treatment. HHcy impaired acetylcholine-induced relaxation in arteries from adult but not young rats. The contraction induced by phenylephrine in carotid arteries in the presence of Y-27632 was reversed to control values in arteries from young but not adult rats with hyperhomocysteinemia. HHcy did not alter the contraction induced by CaCl(2) in carotid arteries from young rats, but enhanced CaCl(2)-induced contraction in the arteries from adult rats. HHcy increased the basal levels of superoxide anion in arteries from both groups. Finally, HHcy decreased the basal levels of nitrite in arteries from adult but not young rats. The major new finding of the present work is that arteries from young rats are more resistant to vascular changes evoked by HHcy than arteries from adult rats. Also, we verified that the enhanced vascular response to phenylephrine observed in carotid arteries of DL-homocysteine thiolactone-treated rats is mediated by different mechanisms in young and adult rats. (C) 2010 Published by Elsevier Inc.
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Introduction: Changes in gait cadence caused by challenging situations in daily life might induce higher demand for strength and propulsion in diabetic neuropathic (DN) subjects. Methods: Forty-six subjects (healthy and DN) walked at two cadences (self-selected and 25% higher). Kinematic and electromyographic data were obtained from lower limbs and compared across the gait cycle. Results: DN subjects showed a delayed peak in plantarflexor activity along the whole cycle (irrespective of cadence) compared with healthy subjects. However, during the imposed cadence, DN individuals showed reduced ankle range of motion along the entire cycle compared with the self-selected condition and healthy individuals walking at both cadences (P = 0.002). Conclusions: These findings suggest that when diabetic individuals face a new challenging situation that induces a higher demand for muscle strength and propulsion, the necessary range of motion and neuromuscular control around distal joints are insufficient. Muscle Nerve 44: 258-268, 2011
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Compared with other specialties, the field of physical and rehabilitation medicine has not received the deserved recognition from clinicians and researchers in the scientific community. One of the reasons is the lack of sound evidence to support the traditional physical and rehabilitation medicine treatments. The best way to change this disadvantage is through a well conducted clinical research, such as standard placebo- or sham-controlled randomized clinical trials. Therefore, having placebo groups in clinical trials is essential to improve the level of evidence-based practice in physical and rehabilitation medicine that ultimately translates to better clinical care. To address the challenges for the use of placebo in physical and rehabilitation medicine and randomized clinical trials and to create useful recommendations, we convened a working group during the inaugural International Symposium in Placebo (February 2009, in Sao Paulo, Brazil) in which the following topics were discussed: (1) current status of randomized clinical trials in physical and rehabilitation medicine, (2) challenges for the use of placebo in physical and rehabilitation medicine, (3) bioethics, (4) use of placebo in acupuncture trials and for the treatment of low-back pain, (5) mechanisms of placebo, and (6) insights from other specialties. The current article represents the consensus report from the working group.
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Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.
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Medulloblastomas are the most common malignant tumors of the central nervous system in childhood. The incidence is about 19-20% between children younger than 16 years old with peak incidence between 4 and 7 years. Despite its sensibility to no specific therapeutic means like chemotherapy and radiotherapy, the treatment is very aggressive and frequently results in regression, growth deficit, and endocrine dysfunction. From this point of view, new treatment approaches are needed such as molecular targeted therapies. Studies in glioblastoma demonstrated that ASPM gene was overexpressed when compared to normal brain and ASPM inhibition by siRNA-mediated inhibits tumor cell proliferation and neural stem cell proliferation, supporting ASPM gene as a potential molecular target in glioblastoma. The aim of this work was to evaluate ASPM expression in medulloblastoma fragment samples, and to compare the results with the patient clinical features. Analysis of gene expression was performed by quantitative PCR real time using SYBR Green system in tumor samples from 37 children. The t test was used to analyze the gene expression, and Mann-Whitney test was performed to analyze the relationship between gene expressions and clinical characteristics. Kaplan-Meier test evaluated curve survival. All samples overexpressed ASPM gene more than 40-fold. However, we did not find any association between the overexpressed samples and the clinical parameters. ASPM overexpression may modify the ability of stem cells to differentiate during the development of the central nervous system, contributing to the development of medulloblastoma, a tumor of embryonic origin from cerebellar progenitor cells.
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Childhood-onset mitochondrial encephalomyopathies are usually severe, relentlessly progressive conditions that have a fatal outcome. However, a puzzling infantile disorder, long known as `benign cytochrome c oxidase deficiency myopathy` is an exception because it shows spontaneous recovery if infants survive the first months of life. Current investigations cannot distinguish those with a good prognosis from those with terminal disease, making it very difficult to decide when to continue intensive supportive care. Here we define the principal molecular basis of the disorder by identifying a maternally inherited, homoplasmic m.14674T > C mt-tRNA(Glu) mutation in 17 patients from 12 families. Our results provide functional evidence for the pathogenicity of the mutation and show that tissue-specific mechanisms downstream of tRNA(Glu) may explain the spontaneous recovery. This study provides the rationale for a simple genetic test to identify infants with mitochondrial myopathy and good prognosis.
Trypan blue staining for capsulorhexis: Ultrastructural effect on lens epithelial cells and capsules
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PURPOSE: To evaluate the ultrastructural effect of trypan blue 0.1% staining for capsulorhexis on lens epithelial cells (LECs) and capsules SETTING: Division of Ophthalmology. University of Sao Paulo, Sao Paulo, Brazil METHODS: Before capsulorhexis, patients were randomly assigned to 1 of 2 groups Trypan blue 0 1% staining was performed in the treatment group No trypan blue was used in the control group Samples of capsules with LECs were fixed and analyzed with routine optical microscopy techniques. immunohistochemistry for beclin-1 expression (a marker of autophagy), terminal deoxynucleotidyl transf erase-mediated dUTP-biotin nick-end labeling to detect apoptosis, and transmission electron microscopy (TEM) Morphometric analyses were performed. and the 2 sets of data were compared. RESULTS: Each group comprised 15 patients Cell death by autophagy and apoptosis was observed in the treatment group but not in the control group The TEM images of subcapsular epithelium cells showed mitochondria` rupture, dilation of the cisterns of the endoplasmic reticulum, increased cytoplasmic and nuclear electron density, and abnormalities in the nuclear profile of trypan blue-stained cells. Morphometric analysis showed statistically significant differences between the 2 groups in the longest nuclear axes and the ratio between the total nuclear perimeter and the cell area (P = .03) The difference in capsule thickness between groups was not significant. CONCLUSION: Trypan blue caused LEC death, which supports the hypothesis that staining with trypan blue 0 1% can help reduce the incidence of posterior capsule pacification after cataract surgery
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Conclusion: The cochlear implant was beneficial as an attempt to restore hearing and improve communication abilities in this patient with profound sensorineural hearing loss secondary to Susac syndrome. Objective: To report the audiological outcomes of cochlear implantation (CI) in a young woman with Susac syndrome after a 6-month follow-up period. Susac syndrome is a rare disorder. It is clinically characterized by a typical triad of sensorineural deafness, encephalopathy, and visual defect, due to microangiopathy involving the brain, inner ear, and retina. Methods: This was a retrospective review of a case at a tertiary referral center. After diagnosis, the patient was evaluated by a multidisciplinary team and received a cochlear implant in her right ear. Results: The patient achieved 100% open-set sentence recognition in noise conditions and 92% monosyllable and 68% medial consonant recognition in quiet conditions after 6 months of implant use. She reported the use of the telephone 3 months after activation.
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Objective: The aim of this study was to evaluate the effects of estrogen and isoflavones on postmenopausal skin morphological parameters. Study design: A randomized, double-blind, estrogen-controlled trial was performed on postmenopausal women treated in the Gynecology Department of the Federal University of Sao Paulo. This study was designed to analyze the effects of topical administration of estradiol and isoflavones on facial skin for 24 weeks. The participants were divided into two groups: G1-17-betaestradiol 0.01% (n = 18) and G2-isoflavones 40% (genistein 4%, n = 18). Skin biopsies were performed on each patient before and after the treatment. The skin samples were processed for histological analysis, stained with haematoxylin and eosin, and examined using light microscopy. Results: After 24 weeks of treatment, the estradiol group had a significant increase in skin parameters analyzed compared to the isoflavone group and to the baseline measurements: epidermal thickness (a 75% increase in the estrogen group and 20% in the isoflavone group), number of dermal papillae (a rise of 125% with estrogen, no significant gain with isoflavones), fibroblasts (a 123% accretion with estradiol, no significant gain with isoflavones), and vessels (a 77% increase with estrogen and 36% with isoflavones). Conclusion: Our data suggest that estrogens may have a stronger effect on histomorphometrical parameters than isoflavones. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
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Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic joint inflammation and continuous immune cell infiltration in the synovium. These changes are linked to inflammatory cytokine release, leading to eventual destruction of cartilage and bone. During the last decade new therapeutic modalities have improved the prognosis, with the introduction of novel biological response modifiers including anti-TNF alpha CTLA4Ig and, more recently, anti-IL6. In the present study we looked at the immunological effects of these three forms of therapy. Serum, obtained from patients with RA was analyzed for TNF alpha, IL6, IL10, IFN gamma, and VEGF, and in parallel, circulating plasmacytoid and myeloid dendritic cells (DC) were enumerated before and after three infusions of the respective biological treatments. After treatment with anti-IL6, we found a significant reduction of IL6 and TNF alpha levels and the percentage of both DC subsets decreased. Although the results did not reach statistical significance for anti-TNF alpha treatment, similar trends were observed. Meanwhile, CTLA4Ig therapy led to the reduction IFN gamma levels only. None of the treatments modified significantly VEGF or IL10 levels. These findings may explain why patients with RA improve more rapidly on IL-6 therapy than with the other two modalities.
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Aims: The heterogeneity of the Brazilian population renders the extrapolation of pharmacogenomic data derived from well-defined ethnic groups inappropriate. We investigated the influence of self-reported `race/color`, geographical origin and genetic ancestry on the distribution of four VKORC1 SNPs and haplotypes in Brazilians. Comparative data were obtained from two major ancestral roots of Brazilians: Portuguese and Africans from former Portuguese colonies. Materials & methods: A total of 1037 healthy adults Brazilians, recruited at four different geographical regions and self identified as white, brown or black (race/color categories), 89 Portuguese and 216 Africans from Angola and Mozambique were genotyped for the VKORC1 3673G>A (rs9923231), 5808T>G (rs2884737), 6853G>C (rs8050894) and 9041G>A (rs7294) polymorphisms using TaqMan (R) (Applied Biosystems, CA, USA) assays. VKORC1 haplotypes were statistically inferred using the haplo.stats software. We inferred the statistical association between the distribution of the VKORC1 polymorphisms among Brazilians and self-reported color, geographical region and genetic ancestry by fitting multinomial log linear models via neural networks. Individual proportions of European and African ancestry were used to assess the impact of genetic admixture on the frequency distribution of VKORC1 polymorphisms among Brazilians, and for the comparison of Brazilians with Portuguese and Africans. Results: The frequency distribution of the 3673G>A and 5808T>G polymorphisms, and VKORC1 haplotypes among Brazilians varies across geographical regions, within self-reported color categories and according to the individual proportions of European and African genetic ancestry. Notably, the frequency of the warfarin sensitive VKORC1 3673A allele and the distribution of VKORC1 haplotypes varied continuously as the individual proportion of European ancestry increased in the entire cohort, independently of race/color categorization and geographical origin. Brazilians with more than 80% African ancestry differ significantly from Angolans and Mozambicans in frequency of the 3673G>A, 5808T>G and 6853G>C polymorphisms and haplotype distribution, whereas no such differences are observed between Brazilians with more than 90% European ancestry and Portuguese individuals. Conclusion: The diversity of the Brazilian population, evident in the distribution of VKORC1 polymorphisms, must be taken into account in the design of pharmacogenetic clinical trials and dealt with as a continuous variable. Warfarin dosing algorithms that include `race` terms defined for other populations are clearly not applicable to the heterogeneous and extensively admixed Brazilian population.
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Structural magnetic resonance imaging and postmortem studies showed volume loss in the hippocampus in schizophrenia. The noted tissue reduction in the posterior section suggests that some cellular subfractions within this structure might be reduced in schizophrenia. To address this, we investigated numbers and densities of neurons, oligodendrocytes and astrocytes in the posterior hippocampal subregions in postmortem brains from ten patients with schizophrenia and ten matched controls using design-based stereology performed on Nissl-stained sections. Compared to the controls, the patients with schizophrenia showed a significant decrease in the mean number of oligodendrocytes in the left and right CA4. This is the first finding of reduced numbers of oligodendrocytes in CA4 of the posterior part of the hippocampus in schizophrenia. Our results are in line with earlier findings in the literature concerning decreased numbers of oligodendrocytes in the prefrontal cortex in schizophrenia. Our results may indicate disturbed connectivity of the CA4 of the posterior part of the hippocampus in schizophrenia and, thus, contribute to the growing number of studies showing the involvement of posterior hippocampal pathology in the pathophysiology of schizophrenia.
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Objective: Gorticosteroids have been proposed to be effective in modulating the inflammatory response and pulmonary tissue remodeling in acute lung injury (ALI). We hypothesized that steroid treatment might act differently in models of pulmonary (p) or extrapulmonary (exp) ALI with similar mechanical compromise. Design: Prospective, randomized, controlled experimental study. Setting: University research laboratory. Subjects: One hundred twenty-eight BALB/c mice (20-25 g). Interventions: Mice were divided into six groups. In control animals sterile saline solution was intratracheally (0.05 mL, Cp) or intraperitoneally (0.5 mL, Gexp) injected, whereas ALI animals received Escherichia coli lipopolysaccharide intratracheally (10 mu g, ALIp) or intraperitoneally (125 mu g, ALIexp). Six hours after lipopolysaccharide administration, ALIp and ALlexp animals were further randomized into subgroups receiving saline (0.1 mL intravenously) or methylprednisolone (2 mg/kg intravenously, Mp and Mexp, respectively). Measurements and Main Results: At 24 hrs, lung state elastance, resistive and viscoelastic pressures, lung morphometry, and collagen fiber content were similar in both ALI groups. KC, interieukin-6, and transforming growth factor (TGF)-beta levels in bronchoatveolar lavage fluid, as well as tumor necrosis factor (TNF)-alpha, migration inhibitory factor (MIF), interferon (IFN)-gamma, TGF-beta 1 and TGF-beta 2 messenger RNA expression in lung tissue were higher in ALIp than in ALIexp animals. Methylprednisolone attenuated mechanical and morphometric changes, cytokine levels, and TNF-alpha, MIF, IFN gamma, and TGF-beta 2 messenger RNA expression only in ALIp animals, but prevented any changes in collagen fiber content in both ALI groups. Conclusions. Methylprednisolone is effective to inhibit fibrogenesis independent of the etiology of ALI, but its ability to attenuate inflammatory responses and lung mechanical changes varies according to the cause of ALI.
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Objective: To evaluate the effectiveness of acupuncture for fibromyalgia. Methods: Fifty-eight women with fibromyalgia were allocated randomly to receive either acupuncture together with tricyclic antidepressants and exercise (n = 34), or tricyclic antidepressants and exercise only (n=24). Patients rated their pain on a visual analogue scale. A blinded assessor evaluated both the mean pressure pain threshold value over all 18 fibromyalgia points and quality of life using SF-36. Results: At the end of 20 sessions, patients who received acupuncture were significantly better than the control group in all measures of pain and in 5 of the SF-36 subscales. After 6 months, the acupuncture group was significantly better than the control group in numbers of tender points, mean pressure pain threshold at the 18 tender points and 3 subscales of SF-36. After one year, the acupuncture group showed significance in one subscale of the SF-36; at 2 years there were no significant differences in any outcome measures. Conclusion: Addition of acupuncture to usual treatments for fibromyalgia may be beneficial for pain and quality of life for 3 months after the end of treatment. Future research is needed to evaluate the specific effects of acupuncture for fibromyalgia.
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Measures employed to control visceral leishmaniasis in Brazil have focused on vector control by residual insecticide spraying and diagnosis of infection with elimination of positive dogs. We describe dog culling and replacement in a Brazilian endemic area (the Alvorada District, Aracatuba, SP) in order to better understand dog population dynamics when elimination of the dog reservoir is adopted as the main control measure. From August 2002 to July 2004, 60.9% of the estimated dog population for the area was culled with a mean age of 34 months old. The presence of anti-Leishmania sp. antibodies was recorded for only 26.7% of the euthanized canines. Replacement was observed in 38.8% of the cases, some of them by 2 or more dogs and in a mean time of 4 months. Dogs were replaced mostly by puppies of both sexes with a mean age of 6.8 months. From August 2002 to April 2005 we were able to follow-up 116 of these dogs, during a mean time of 8.7 months. Canine visceral leishmaniasis seropositivity by ELISA was observed in 42.2% of the followed dogs, 30.6% of which were already positive at the first evaluation. By the end of the follow-up period 37% of the dogs were submitted to euthanasia, with a mean age of 18.3 months. In the studied CVL endemic area of Brazil, euthanasia and the subsequent replacement ratio were high, increasing the dog population turnover and leading to a younger population that might be more susceptible to a variety of other infectious diseases in addition to CVL. Dog culling as a control strategy for VL should be reassessed. (C) 2008 Elsevier B.V. All rights reserved.