63 research outputs found

    Tempo and Mode in Evolution of Transcriptional Regulation

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    Perennial questions of evolutionary biology can be applied to gene regulatory systems using the abundance of experimental data addressing gene regulation in a comparative context. What is the tempo (frequency, rate) and mode (way, mechanism) of transcriptional regulatory evolution? Here we synthesize the results of 230 experiments performed on insects and nematodes in which regulatory DNA from one species was used to drive gene expression in another species. General principles of regulatory evolution emerge. Gene regulatory evolution is widespread and accumulates with genetic divergence in both insects and nematodes. Divergence in cis is more common than divergence in trans. Coevolution between cis and trans shows a particular increase over greater evolutionary timespans, especially in sex-specific gene regulation. Despite these generalities, the evolution of gene regulation is gene- and taxon-specific. The congruence of these conclusions with evidence from other types of experiments suggests that general principles are discoverable, and a unified view of the tempo and mode of regulatory evolution may be achievable

    Ecological phytochemistry of Cerrado (Brazilian savanna) plants

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    The Cerrado (the Brazilian savanna) is one of the vegetation formations of great biodiversity in Brazil and it has experienced strong deforestation and fragmentation. The Cerrado must contain at least 12,000 higher plant species.We discuss the ecological relevance of phytochemical studies carried out on plants from the Cerrado, including examples of phytotoxicity, antifungal, insecticidal and antibacterial activities. The results have been classified according to activity and plant family. The most active compounds have been highlighted and other activities are discussed. A large number of complex biochemical interactions occur in this system. However, only a small fraction of the species has been studied from the phytochemical viewpoint to identify the metabolites responsible for these interactions

    Reduction of microglial activity in a model of multiple sclerosis by dipyridamole

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    BACKGROUND: Despite extensive and persistent activation of microglia in multiple sclerosis (MS), microglia inhibitors have not yet been identified for treatment of the disorder. We sought to identify medications already in clinical use that could inhibit the activation of microglia. On the basis of the reported inhibitory effects of dipyridamole on phosphodiesterase activity that result in the production of various anti-inflammatory outcomes, we selected it for study. Dipyridamole is used clinically for secondary prevention in stroke. In this study, dipyridamole was examined using microglia in culture and in the mouse model of MS, experimental autoimmune encephalomyelitis (EAE). RESULTS: We found that dipyridamole attenuated the elevation of several cytokines and chemokines in human microglia caused by Toll-like receptor stimulation. Morphological characteristics of activated microglia in culture were also normalized by dipyridamole. In mice, dipyridamole decreased the clinical severity of EAE and reduced microglial activity and other histological indices of EAE in the spinal cord. CONCLUSIONS: Dipyridamole is an inhibitor of microglia activation and may have a role in MS and other neurological conditions to attenuate microglial activity

    Natural environments, ancestral diets, and microbial ecology: is there a modern “paleo-deficit disorder”? Part II

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    Lower eyelid repair utilizing triangular skin flaps with subcutaneous pedicles

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    Made available in DSpace on 2019-09-12T16:53:30Z (GMT). No. of bitstreams: 0 Previous issue date: 1991Fifty-four patients were studied during the period from 1984 to 1989. The lower eyelid was repaired in 55 cases utilising a triangular flap with a subcutaneous pedicle. Repair was achieved in 39 cases with a triangular flap only and in 16 it was necessary to use a chondromucosal graft of nasal septum as well. The method is described and is feasible for repairs ranging from the simplest to the most complex in different locations of the lid.Universidade de Taubaté (Unitau),HOSP TRAINING,PLAST SURG SERV,SAO PAULO,BRAZIL; FED UNIV MINAS GERAIS,SCH MED,BR-30000 BELO HORIZONTE,MG,BRAZI

    Latin American study on patient acceptance of the International Prostate Symptom Score (IPSS) in the evaluation of symptomatic benign prostatic hyperplasia

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    Objectives. To determine the acceptance of the self-administered International Prostate Symptom Score (IPSS) by people of differing educational levels in two different countries. Methods. The questionnaire adopted by the World Health Organization and known as the IPSS attempts to measure the severity of lower urinary tract symptoms in men with benign prostatic hyperplasia. An international study was performed in Brazil and Argentina and included 768 patients. The IPSS was self-administered and used to evaluate and quantify the clinical symptoms resulting from benign prostatic hyperplasia. The patients were asked not to answer any questions that they did not clearly understand or about which they were unsure of the information they should give. The patients were assessed into two subgroups according to their level of education. The Brazilian group consisted of 458 men in which subgroup 1 was composed of 244 (53%) men who had an elementary school education, whereas subgroup 2 consisted of 214 (47%) men who had a higher education level, including a university degree. The Argentinian group consisted of 310 patients, 158 (51%) of whom had an elementary school education, whereas the remaining 152 (49%) had received higher education, including a university degree. Results. A total of 77 men (16.8%), 35 (45.5%) from subgroup 1 and 42 (54.5%) from subgroup 2, failed to complete the questionnaire. The difference between the two subgroups was not significant. A total of 189 questions were not answered. There was no significant difference among the three questions most frequently unanswered by each subgroup. A total of 40 (12.9%) men filled out the questionnaire incompletely, 31 (77.5%) in the lower-education subgroup and 9 (22.5%) in the higher-education subgroup. An incomplete questionnaire was more frequent among the patients with lower education (P <0.01). Conclusions. In spite of the cultural variations, there was no significant difference in the number of patients unable to answer the questionnaire in the two countries. Copyright 1997 by Elsevier Science Inc.491464
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