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991.
Marcos da Silveira Regueira‐Neto Saulo Relison Tintino Ana Raquel Pereira da Silva Maria do Socorro Costa Cícera Datiane de Morais Oliveira‐Tintino Aline Augusti Boligon Irwin R. A. Menezes Valdir de Queiroz Balbino Henrique Douglas Melo Coutinho 《化学与生物多样性》2019,16(9)
The aim of this study was to investigate the antibacterial activity of red propolis and resin and their association with standard antibiotics to evaluate possible differences of activity. We also submitted red propolis and the resin to a HPLC analysis to confirm the botanical origin. The extracts were tested against P. aeruginosa and S. aureus alone and in association with gentamicin and imipenem. The HPLC analysis identified seven compounds with six of them present in both substances. The lowest MIC values obtained in this study were observed against S. aureus. In general, MIC values showed to be lower for red propolis against all species tested in comparison to resin. Despite the synergistic behavior to be similar for both substances, we observed that inhibitory concentrations of drugs were lower when associated with red propolis in comparison to resin. 相似文献
992.
Paulo S. G. de Mattos Neto George D. C. Cavalcanti Francisco Madeiro Tiago A. E. Ferreira 《PloS one》2015,10(9)
The particulate matter (PM) concentration has been one of the most relevant environmental concerns in recent decades due to its prejudicial effects on living beings and the earth’s atmosphere. High PM concentration affects the human health in several ways leading to short and long term diseases. Thus, forecasting systems have been developed to support decisions of the organizations and governments to alert the population. Forecasting systems based on Artificial Neural Networks (ANNs) have been highlighted in the literature due to their performances. In general, three ANN-based approaches have been found for this task: ANN trained via learning algorithms, hybrid systems that combine search algorithms with ANNs, and hybrid systems that combine ANN with other forecasters. Independent of the approach, it is common to suppose that the residuals (error series), obtained from the difference between actual series and forecasting, have a white noise behavior. However, it is possible that this assumption is infringed due to: misspecification of the forecasting model, complexity of the time series or temporal patterns of the phenomenon not captured by the forecaster. This paper proposes an approach to improve the performance of PM forecasters from residuals modeling. The approach analyzes the remaining residuals recursively in search of temporal patterns. At each iteration, if there are temporal patterns in the residuals, the approach generates the forecasting of the residuals in order to improve the forecasting of the PM time series. The proposed approach can be used with either only one forecaster or by combining two or more forecasting models. In this study, the approach is used to improve the performance of a hybrid system (HS) composed by genetic algorithm (GA) and ANN from residuals modeling performed by two methods, namely, ANN and own hybrid system. Experiments were performed for PM2.5 and PM10 concentration series in Kallio and Vallila stations in Helsinki and evaluated from six metrics. Experimental results show that the proposed approach improves the accuracy of the forecasting method in terms of fitness function for all cases, when compared with the method without correction. The correction via HS obtained a superior performance, reaching the best results in terms of fitness function and in five out of six metrics. These results also were found when a sensitivity analysis was performed varying the proportions of the sets of training, validation and test. The proposed approach reached consistent results when compared with the forecasting method without correction, showing that it can be an interesting tool for correction of PM forecasters. 相似文献
993.
Monique Matsuda Rodolfo Bonatti M?nica V. Marquezini Maria L. B. Garcia Ubiratan P. Santos Alfésio L. F. Braga Milton R. Alves Paulo H. N. Saldiva Mário L. R. Monteiro 《PloS one》2015,10(11)
Background
Air pollution is one of the most environmental health concerns in the world and has serious impact on human health, particularly in the mucous membranes of the respiratory tract and eyes. However, ocular hazardous effects to air pollutants are scarcely found in the literature.Design
Panel study to evaluate the effect of different levels of ambient air pollution on lacrimal film cytokine levels of outdoor workers from a large metropolitan area.Methods
Thirty healthy male workers, among them nineteen professionals who work on streets (taxi drivers and traffic controllers, high pollutants exposure, Group 1) and eleven workers of a Forest Institute (Group 2, lower pollutants exposure compared to group 1) were evaluated twice, 15 days apart. Exposure to ambient PM2.5 (particulate matter equal or smaller than 2.5 μm) was 24 hour individually collected and the collection of tears was performed to measure interleukins (IL) 2, 4, 5 and 10 and interferon gamma (IFN-γ) levels. Data from both groups were compared using Student’s t test or Mann- Whitney test for cytokines. Individual PM2.5 levels were categorized in tertiles (lower, middle and upper) and compared using one-way ANOVA. Relationship between PM2.5 and cytokine levels was evaluated using generalized estimating equations (GEE).Results
PM2.5 levels in the three categories differed significantly (lower: ≤22 μg/m3; middle: 23–37.5 μg/m3; upper: >37.5 μg/m3; p<0.001). The subjects from the two groups were distributed unevenly in the lower category (Group 1 = 8%; Group 2 = 92%), the middle category (Group 1 = 89%; Group 2 = 11%) and the upper category (Group 1 = 100%). A significant relationship was found between IL-5 and IL-10 and PM2.5 levels of the group 1, with an average decrease of 1.65 pg/mL of IL-5 level and of 0.78 pg/mL of IL-10 level in tear samples for each increment of 50 μg/m3 of PM2.5 (p = 0.01 and p = 0.003, respectively).Conclusion
High levels of PM2.5 exposure is associated with decrease of IL-5 and IL-10 levels suggesting a possible modulatory action of ambient air pollution on ocular surface immune response. 相似文献994.
Carla Andréa Avelar Pires Fernando Octávio Machado Jucá Neto Nahima Castelo de Albuquerque Geraldo Mariano Moraes Macedo Keila de Nazaré Madureira Batista Marília Brasil Xavier 《PLoS neglected tropical diseases》2015,9(6)
BackgroundLeprosy, caused by Mycobacterium leprae, can lead to scarring and deformities. Human immunodeficiency virus (HIV), a lymphotropic virus with high rates of replication, leads to cell death in various stages of infection. These diseases have major social and quality of life costs, and although the relevance of their comorbidity is recognized, several aspects are still not fully understood.Conclusions/SignificanceThis study used a large sample and makes a significant contribution to the clinical outcomes of patients in the reactive state with comorbid HIV and leprosy. The data indicate that these diseases, although concurrent, have independent courses. 相似文献
995.
Gustavo Torres de Souza Claudinéia Pereira Maranduba Camila Maurmann de Souza Danielle Luciana Aurora Soares do Amaral Francisco Carlos da Guia Rafaella de Souza Salom?o Zanette Jo?o Vitor Paes Rettore Natana Chaves Rabelo Lucas Mendes Nascimento ícaro Fran?a Navarro Pinto Júlia Boechat Farani Abrah?o Elias Hallack Neto Fernando de Sá Silva Carlos Magno da Costa Maranduba Angelo Atalla 《World journal of stem cells》2015,7(1):106-115
Despite the advances in the hematology field, blood transfusion-related iatrogenesis is still a major issue to be considered during such procedures due to blood antigenic incompatibility. This places pluripotent stem cells as a possible ally in the production of more suitable blood products. The present review article aims to provide a comprehensive summary of the state-of-theart concerning the differentiation of both embryonic stem cells and induced pluripotent stem cells to hematopoietic cell lines. Here, we review the most recently published protocols to achieve the production of blood cells for future application in hemotherapy, cancer therapy and basic research. 相似文献
996.
Macedo T. Z. Okada D. Y. Delforno T. P. Braga J. K. Silva E. L. Varesche M. B. A. 《Bioprocess and biosystems engineering》2015,38(10):1835-1844
Bioprocess and Biosystems Engineering - The efficiency of linear alkylbenzene sulfonate (LAS) removal from laundry wastewater and the related microbial community was investigated in an anaerobic... 相似文献
997.
Plasma Cytokine Levels Fall in Preterm Newborn Infants on Nasal CPAP with Early Respiratory Distress
Clarissa Gutierrez Carvalho Rita de Cassia Silveira Eurico Camargo Neto Renato Soibelmann Procianoy 《PloS one》2015,10(3)
Introduction
Early nCPAP seems to prevent ventilator-induced lung injury in humans, although the pathophysiological mechanisms underlying this beneficial effect have not been clarified yet.Objective
To evaluate plasma levels IL-1β, IL-6, IL-8, IL-10, and TNF-α immediately before the start of nCPAP and 2 hours later in preterm infants.Methods
Prospective cohort including preterm infants with 28 to 35 weeks gestational age with moderate respiratory distress requiring nCPAP. Extreme preemies, newborns with malformations, congenital infections, sepsis, surfactant treatment, and receiving ventilatory support in the delivery room were excluded. Blood samples were collected right before and 2 hours after the start of nCPAP.Results
23 preterm infants (birth weight 1851±403 grams; GA 32.3±1.7 weeks) were treated with nCPAP. IL-1β, IL-10, TNF-α levels were similar, IL-8 levels were reduced in 18/23 preterm infants and a significant decrease in IL-6 levels was observed after 2 hours of nCPAP. All newborns whose mothers received antenatal steroids had lower cytokine levels at the onset of nCPAP than those whose mothers didn’t receive it; this effect was not sustained after 2 hours of nCPAP.Conclusion
Early use nCPAP is not associated with rising of plasma pro-inflammatory cytokines and it seems to be a less harmful respiratory strategy for preterm with moderate respiratory distress. 相似文献998.
The role of effective mass and hand speed in the performance of kung fu athletes compared with nonpractitioners 总被引:1,自引:0,他引:1
The main goal of this article is to quantify the contribution of effective mass (me) and handspeed (shi) on the palm strike performance of kung fu athletes (kung fu group) compared with nonpractitioners (control group). All subjects were asked to strike a basketball. Hand and ball speed (sbf) were determined by high-speed video analysis. The value for me was determined by an equation that does not depend upon postimpact measurement of the hand speed. The results show that kung fu athletes had greater shi (6.67 [SD 1.42] m/s), p = 0.042), higher me (2.62 [SD 0.33] kg, p = 0.004), and greater sbf (9.00 [SD 1.89] m/s), p = 0.004) than the nonpractitioners (5.04 [SD 0.57] m/s, 1.33 [SD 0.19] kg, and 5.72 [SD 0.44] m/s, respectively). Comparing the average values obtained for me and hand and forearm mass (m), it was found that for the control group me is statistically equal to m (p = 0.917), whereas for the kung fu group me is significant greater than m (p = 0.003). It is suggested that for impacts against heavier objects, the effective mass would be the main factor to distinguish a martial arts-trained from an untrained subject. 相似文献
999.
1000.
Oliveira MF Gandara AC Braga CM Silva JR Mury FB Dansa-Petretski M Menezes D Vannier-Santos MA Oliveira PL 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2007,146(1-2):168-174
Hemozoin (Hz) is a heme crystal produced by several blood-feeding organisms in order to detoxify free heme released upon hemoglobin (Hb) digestion. Here we show that heme crystallization also occurs in three species of triatomine insects. Ultraviolet-visible and infrared light absorption spectra of insoluble pigments isolated from the midgut of three triatomine species Triatoma infestans, Dipetalogaster maximus and Panstrongylus megistus indicated that all produce Hz. Morphological analysis of T. infestans and D. maximus midguts revealed the close association of Hz crystals to perimicrovillar membranes and also as multicrystalline assemblies, forming nearly spherical structures. Heme crystallization was promoted by isolated perimicrovillar membranes from all three species of triatomine bugs in vitro in heat-sensitive reactions. In conclusion, the data presented here indicate that Hz formation is an ancestral adaptation of Triatominae to a blood-sucking habit and that the presence of perimicrovillar membranes plays a central role in this process. 相似文献