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Influence of Sub-Lethal and Lethal Concentrations of Chlorhexidine on Morphology and Glucosyltransferase Genes Expression in Streptococcus mutans UA159

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Advances in Microbiology 2014年第13期4卷 945-954页

作者： Andréa Cristina Barbosa da silva Rafael Nóbrega Stipp Renata de Oliveira Mattos-Graner fábio Correia Sampaio demetrius Antonio Machado de Araújo Graduate Program in dentistry Center of SciencesTechnology and HealthState University of ParaibaUEPBArarunaParaíbaBrazil department of Oral Diagnosis Piracicaba Dental SchoolUniversity of CampinasUNICAMPSao PauloBrazil department of Clinical and Social dentistry Health Science CenterBrazilian Northeast Network on BiotechnologyFederal University of ParaibaJoao PessoaBrazil department of Biotechnology Center of BiotechnologyBrazilian Northeast Network on BiotechnologyFederal University of ParaibaJoao PessoaBrazil

Chlorhexidine (CHX) is regarded as one of the most successful antiplaque agents in controlling the formation of dental biofilm. Nevertheless, molecular mechanisms of their effects in Streptococcus mutans are largely unknown. In this work, the effects of sub-lethal and lethal concentrations of chlorhexidine (CHX) on planktonic or biofilm-organized Streptococcus mutans cells were investigated in dose- and time-dependent manner. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) for planktonic cells and biofilm conditions were determined by standard methods. Quantitative PCR (qPCR) was used to quantify the relative levels of glucosyltransferase B (gtfB), gtfC and gtfD transcription of S. mutans in the presence of CHX. The CHX activity in the initial biofilm structure and morphological alterations in planktonic cells were examined by Scanning Electron Microscopy (SEM). The results indicate that CHX increased expression of gtfC and gtfD in planktonic S. mutans cells and CHX reduced the expression of gtfB, gtfC, and gtfD in biofilms. High concentrations of CHX resulted in several wilted S. mutans planktonic cells with spilled intracellular material, while decreased cells’ chain length and matrix was found when the initial biofilm was exposed to increasing concentrations of CHX. CHX’s effects against bacteria depend on the type of growth organization and the concentration and time of exposure to the drug. At sub-lethal concentrations, CHX affects the expression of glucosyltransferases, which may have anticariogenic effect.

关键词： Planktonic Cells Biofilm Microorganism Scanning Electron Microscopy

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Gas Exchange and Growth of Medicinal Plant Subjected to Salinity and Application of Biofertilizers

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American Journal of Plant Sciences 2014年第16期5卷 2520-2527页

作者： Sergiane Beatriz da silva Mesquita Jose Adriano da silva Rafael Santiago da Costa Moises Wilkson Nunes dos Santos Claudivan feitosa de Lacerda Aiala Vieira Amorim Antonio Marcos Esmeraldo Bezerra Universidade da Integracao Internacional da Lusofonia Afro-Brasileira(UNILAB) Campus da LiberdadeRedencaoBrasil Universidade federal do Ceará(UfC) FortalezaBrasil

The objective of this study was to evaluate the use of biofertilizers and saline waters on gas exchange and growth of medicinal plant Plectrantus amboinicus. The experiment was conducted in the period february to May 2013 in a greenhouse. The experimental design was completely randomized in a 2 × 4 factorial arrangement, with two levels of salinity of irrigation water (ECw: 0.7 and 3.1 dS m-1) and four levels of bovine liquid biofertilizer applied to the soil, corresponding to 0%, 10%, 20% and 30% of the soil volume, with five replications. The experiment lasted 60 days, counted from the beginning of the treatments. The stomatal conductance (gs), photosynthesis (A), transpiration (E), intrinsic water use efficiency (WUEi) were performed at the end of the experiment, and the height, number of leaves and stem diameter at the beginning and at the end. Generally plants subjected to salinity of irrigation water of 3.1 dS m-1 had the lowest values of gas exchange. Moreover, the application of biofertilizers and the interaction between this and salinity did not affect any growth variable studied except the stem length in the final phase which was influenced by salinity at 5% probability by f test. The average values of this variable were 57.22 cm and 69.65 cm when applied water ECw: 0.7 to 3.1 dS m-1, respectively. The application of biofertilizers can reduce the effect of salinity on the final plant height of Plectrantus amboinicus, especially when the plants were fertilized with a dose of 20% of biofertilizers.

关键词： Medicinal Plants Salt Stress fertilizers

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航空轮胎胎面胶配方

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现代橡胶技术 2018年第2期44卷 31-40页

作者：文兴 José Carlos araujo da silva Aurélie TRIGUEL

本发明是有关航空轮胎的发明。本发明轮胎的胎面胶配方至少有一种二烯系橡胶、一种补强填充剂和一种交联体系。二烯系橡胶为乙烯、α-烯烃和非共轭二烯的三元聚合物。本发明轮胎可明显改善着陆性能,特别是可明显改善在非常高速下的轮胎... 详细信息

本发明是有关航空轮胎的发明。本发明轮胎的胎面胶配方至少有一种二烯系橡胶、一种补强填充剂和一种交联体系。二烯系橡胶为乙烯、α-烯烃和非共轭二烯的三元聚合物。本发明轮胎可明显改善着陆性能,特别是可明显改善在非常高速下的轮胎耐磨性。

关键词：航空轮胎胎面胶配方耐磨性

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Red Onion (Allium Cepa L.) Methanolic Extract Increases Extracellular Nucleotide Hydrolysis in Rat Serum

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Open Journal of Applied Sciences 2020年第12期10卷 864-876页

作者： Janayne Luihan silva Bruno Quintanilha faria Vinícius Marques Arruda fernanda Cardoso da silva Joyce ferreira da Costa Guerra Cristina Ribas fürstenau Instituto de Ciências Biológicas Universidade Federal de Minas Gerais Belo Horizonte Brazil Curso de Biotecnologia Universidade Federal de Uberlandia Patos de Minas Brazil Programa de Pós-graduaç o em Biotecnologia Instituto de Biotecnologia Universidade Federal de Uberlandia Patos de Minas Brazil Centro de Ciências Naturais e Humanas Universidade Federal do ABC Santo André Brazil

Ectonucleotidases are enzymes involved in nucleotides metabolism. The amount of circulating nucleotides may modulate distinct pathophysiological processes in the vasculature, including platelet aggregation and vascular tone. Onion (Allium cepa L.) phenolic compounds modulate enzymatic activity. The present study evaluated the total phenolic content of red onion methanolic extract, its antioxidant capacity, and its ability to interfere in nucleotides hydrolyses in rat serum. Total phenolic content was determined with the folin-Ciocalteau reagent using gallic acid as a standard, while total flavonoid content was obtained through the aluminum chloride colorimetric method with quercetin as a standard. Antioxidant capacity was evaluated from the ability of the extract to scavenge ABTS·+ and DPPH· radicals. ATP, ADP, AMP, and p-Nph-5'-TMP hydrolyses were colorimetrically determined in response to different onion extract concentrations (0, 125, 250, 500, or 1000 μg/mL). Phenolic content of the extract was 54.35 mg GAE 100 g-1 sample, while flavonoid content was 7.22 mg quercetin g-1 sample. The IC50 value for ABTS·+ was 374.13 ± 7.52 μg/mL, while it was 440.29 ± 15.17 μg/mL for DPPH·. Red onion extract increased ADP and p-Nph-5'-TMP hydrolysis. The results confirmed that red onion contains high content of antioxidant, mainly flavonoids, and high antioxidant capacity. Additionally, biochemical studies suggest that the increased ADP breakdown may be important to regulate vascular processes. As it occurs for other enzymes, the antioxidant capacity of onion extract may neutralize reactive oxygen species (ROS) formation and favor ectonucleotidase activity and the hydrolysis of ADP, a major platelet agonist.

关键词： Red Onion flavonoids Reactive Oxygen Species Ectonucleotidases Vascular Homeostasis

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Hepatocellular Carcinoma: Risk factors, Diagnosis, Staging and Treatment in a Referral Centre

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Journal of Cancer Therapy 2013年第2期4卷 384-393页

作者： Raphael Raphe Willian J. Duca Paulo C. Arroyo Jr. Rita C. da silva Renato f. da silva Postgrauduate Course Faculty of Medicine of Sao Jose do Rio Preto FAMERP Sao Jose do Rio Preto Brazil Unit of Surgery and Liver Transplant Department of Surgery Hospital de Base FUNFARME/FAMERP Sao Jose do Rio Preto Brazil Unit of Surgery and Liver Transplant Department of Medicine Hospital de Base FUNFARME/FAMERP Sao Jose do Rio Preto Brazil

Introduction: Hepatocellular carcinoma is the most common primary neoplasm of the liver and a significant cause of mortality in patients with cirrhosis. A retrospective cross-sectional study was performed to analyze epidemiological aspects related to risk factors, diagnosis, staging and first-line treatment in a closed population. Methods: The medical records of patients seen between November 1998 and May 2011 were revisited. Results: Of the 272 patients included in this study, 229 (84.2%) were male and the average age was 57.1 years (standard deviation 10.9 years). The most common etiology was hepatitis C virus infection in 145 (55.1%) patients, with this being the single cause in 88 (33.4%) patients. The largest masses ranged from 6 mm to 260 mm in diameter with a mean of 61.4 mm (standard deviation 41.5 mm). Only one mass was found in 145 (64.2%) cases, two masses in 26 (11.5%), three masses in 9 (4%) and 46 patients (20.3%) had multifocal disease. Early stage disease was diagnosed in 47 patients (22.0%), advanced stage in 65 (30.4%) and terminal stage in 32 (14.9%). Hepatocellular carcinoma was found by chance in 11%. Diagnosis was by means of imaging in 175 (68.1%) cases. The level of alpha-fetoprotein was measured in 209 patients, with 29.2% having levels lower than 20 ng/mL and 34.9% having levels above 400 ng/mL. Specific treatment was administered in 236 patients (86.8%) with hepatic chemoembolization in 127 (46.7%) and liver transplantation in 72 (26.5%);of these 33 (45.8%) received hepatic chemoembolization as a bridge to transplantation. Thirty-four patients (12.5%) received only supportive therapy. Conclusions: Patients are chiefly male and disease involvement generally occurs in the 5th decade of life. Cirrhosis was present in most patients and hepatitis C virus infection was the commonest etiologic agent. Only one imaging examination was required for diagnosis in most patients. The measurement of alpha-fetoprotein levels did not prove to be a good too

关键词： Hepatocellular Carcinoma Epidemiology Risk factors Liver Cancer Hepatitis Alcohol

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Cluster Analysis for Political Scientists

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Applied Mathematics 2014年第15期5卷 2408-2415页

作者： dalson Britto figueiredo filho Enivaldo Carvalho da Rocha José Alexandre da silva Júnior Ranulfo Paranhos Mariana Batista da silva Bárbara Sofia félix Duarte department of Political Science Federal University of Pernambuco Recife Brazil Institute of Social Science Federal University of Alagoas Maceió Brazil

This paper provides an intuitive introduction to cluster analysis. Our targeting audience are both scholars and students in Political Science. Methodologically, we use basic simulation to illustrate the underlying logic of cluster analysis and we replicate data from Coppedge, Alvarez and Maldonado (2008)?[1]?to classify political regimes according to dahl’s (1971)?[2]?polyarchy dimensions: contestation and inclusiveness. With this paper, we hope to help novice scholars to understand and employ cluster analysis in Political Science empirical research.

关键词： Cluster Analysis Q Analysis Political Regimes

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Peptides Radiofluorination: Main Methods and Highlights

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International Journal of Organic Chemistry 2022年第4期12卷 161-172页

作者： Ana Carolina A. Bispo fernanda A. f. Almeida Juliana B. silva Marcelo Mamede Radiopharmaceutical Research and Production Unit Nuclear Technology Development Center Belo Horizonte Brazil Anatomy and Imaging department Faculty of Medicine Federal University of Minas Gerais Belo Horizonte Brazil

Peptides have an important role in organism and its high quantity present in tumors leading to development of radiolabeled peptides for tumor-specific imaging. Once the traditional methodologies used for radiofluorination do not work with peptides, due to their harsh conditions, other radiolabeling strategies had to be developed to supply the need. Direct radiofluorination is either an inefficient method, and the use of bidirectional groups, or prosthetic groups, is needed to enable the binding between the radionuclide fluorine-18 and a peptide functionalized. New peptides radiolabeling strategies have been developed sourcing increase the synthesis yield, its chemoselectivity, and the binding stability, and reduce the total process time and the number of steps required. The progress of radiofluorination methodologies led to development of the amidation, acylation, imidation, and alkylation techniques, the use of thiol groups, photochemical conjugation, chemoselective reactions, and “click chemistry”, in addition to use of fDG molecule and heteroatoms as linkers. This paper presents the main strategies used for peptides radiofluorination, presenting their positive and negative points, and the prosthetic groups most used in each method.

关键词： Radiofluorination Radiolabeling Peptides Prosthetic Groups fluorine-18

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Mental functioning of Workers with Cancer Diagnosis by Brazilian Version of the Work Role functioning Questionnaire—WRfQ-Br

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Health 2016年第14期8卷 1495-1505页

作者： Cristiane Helena Gallasch Neusa Maria Costa Alexandre Sergio Carlos Barros Esteves Eugenio fuentes Pérez Júnior Magda Guimarães de araujo faria Elias Barbosa de Oliveira Priscila Cristina da silva Thiengo Patricia Campos Pavan Baptista faculty of Nursing Rio de Janeiro State University Rio de Janeiro Brazil Post Graduation Programs Professor Group of Studies and Researches in Occupational Health and Ergonomics Leader Faculty of Nursing State University of Campinas Campinas Brazil CAISM Hospital da Mulher Dr. José Aristodemo Pinotti State University of Campinas Campinas Brazil Post Graduation and Under Graduation Programs Professor Mental Health and Work Study Group Leader (GESMT) Faculty of Nursing Rio de Janeiro State University Rio de Janeiro Brazil Post Graduation and Under graduation Programs Professor Leader of the Group of Studies on the Health of Nursing Worker (GESTE) School of Nursing University of S&atilde o Paulo S&atilde o Paulo Brazil

Aim: To evaluate data related to mental work functioning of workers with cancer diagnosis in radiotherapy in a private service in the city of Campinas, State of São Paulo, Brazil. Method: It consists in a cross-sectional, observational and analytical study with comparison between cancer patients and healthy people, using the Brazilian version of the Work Role functioning Questionnaire (WRfQ-Br). descriptive and statistical analysis is performed by the Mann-Whitney test. Results: There was a significant difference between the groups in the evaluation of mental demand;however, the population diagnosed with malignant neoplasm submitted to radiotherapy had unexpected higher scores, reflecting lower mental exigency. Conclusions: The observed context may occur due to extensive support of family, government and interdisciplinary team of health care for individuals diagnosed with cancer. This data provide support for new research studies related to the importance of the work to promote mental health, considering aspects related to social interaction and productivity as the support system members. The importance of disseminating these results and limitation is based in the necessity of investments to improve research and actions to promote the permanence and early return to work for cancer survivors in Brazil and Latin America.

关键词： Neoplasms Mental Health Social Support Occupational Health Nursing

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Environmental assessment and nano-mineralogical characterization of coal,overburden and sediment from Indian coal mining acid drainage

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地学前缘：英文版 2017年第6期8卷 1285-1297页

作者： Madhulika Dutta Jyotilima Saikia Silvio R.Taffarel frans B.Waanders Diego de Medeiros Cesar M.N.L.Cutruneo Luis f.O.silva Binoy K.Saikia department of Chemistry CNB CollegeBokakhat785612AssamIndia Polymer Petroleum and Coal Chemistry Group Materials Science and Technology DivisionCSIR-North East Institute of Science&TechnologyJorhat785006India School of Applied Sciences Department of ChemistryUniversity of Science&TechnologyMeghalayaIndia Academy of Scientific Innovative Research CSIR-NEIST CampusJorhat785006India Laboratory of Environmental Researches and Nanotechnology development Centro Universitario La SalleMestrado em Avaliacao de Impactos Ambientais em MineracaoVictor Barreto2288 Centro92010-000CanoasRSBrazil School of Chemical and Minerals Engineering North West University(Potchefstroom Campus)Potchefstroom2531South Africa Research Group in Environmental Management and Sustainability Faculty of Environmental SciencesUniversidad De La CostaCalle 58#55-66080002BarranquillaAtla nticoColombia Universidade do Vale do Rio dos Sinos.Av.Unisinos 950 Cristo Rei 90510030Sao LeopoldoRSBrazil

The deterioration of environmental conditions is the major contributory factor to poor health and quality of life that hinders sustainable development in any *** mining is one of the major industries that contribute to the economy of a country but it also impacts the *** chemical parameters of the coal,overburden,soil and sediments along with the coal mine drainage(CMD)were investigated in order to understand the overall environmental impact from high sulphur coal mining at northeastern coalfield(India).It was found that the total sulphur content of the coal is noticeably high compared to the overburden(OB)and *** volatile matter of the coal is sufficiently high against the high ash content of the soil and *** water samples have a High Electrical Conductivity(EC)and high Total Dissolve Solid(TDS).Lower values of pH,indicate the dissolution of minerals present in the coal as well as other minerals in the mine rejects/*** chemical and nano-mineralogical composition of coal,soil and overburden samples was studied using a High Resolution-Transmission Electron Microscopy(HR-TEM),Energy Dispersive Spectroscopy(EDS),Selected-Area Diffraction(SAED),field Emission-Scanning Electron Microscopy(fE-SEM)/EDS,X-ray diffraction(XRD),fourier Transform Infrared Spectroscopy(fTIR),Raman and Ion-Chromatographic analysis,and Mossbauer *** different geochemical analysis it has been found that the mine water sample from Ledo colliery has the lowest pH value of 3.30,Tirap colliery samples have the highest electrical conductivity value of5.40 ms cm^(-1)Both Ledo and Tirap coals have total sulphur contents within the range 3-3.50%.The coal mine water from Tirap colliery(TW-15 B)has high values of Mg^(2+)(450 ppm),and Br^-(227.17 ppm).XRD analysis revealed the presence of minerals including quartz and hematite in the *** analysis of coal mine overburden(OB)indicates the presence both of pyrite and marcasite which was also

关键词： Coal mine drainage Environmental assessment Indian coal Chemical analysis Nano-mineralogy Advance characterization

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Ambient nanoparticles/nanominerals and hazardous elements from coal combustion activity:Implications on energy challenges and health hazards

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Geoscience frontiers 2018年第3期9卷 863-875页

作者： Binoy K.Saikia Jyotilima Saikia Shahadev Rabha Luis f.O.silva Robert finkelman Polymer Petroleum and Coal Chemistry Group Materials Science and Technology DivisionCSIR-North East Institute of Science and TechnologyJorhat785006AssamIndia Academy of Scientific and Innovative Research CSIR-NEIST CampusJorhat785006India Research group in Environmental Management and Sustainability Department of Civil and Environmental EngineeringUniversidad de la CostaBarranquillaColombia University of Texas at dallas RichardsonTXUSA

Coal is the most abundant fossil fuel in the world. Because of the growth of coal mining, coal-fired power plants and coal-burning industries, the increase of the emission of particulates(coarse, fine or ultrafine)is of great concern. There is a relationship between increasing human morbidity and mortality and progressive environmental air pollution caused by these types of particles. Thus, the knowledge of the physico-chemical composition and ambient concentrations of coal-derived nanoparticles will improve pollution control strategy. Given the current importance of this area of research, the advanced characterization of this coal combustion-derived nanoparticles/nanominerals as well as hazardous elements is likely to be one of the hottest research fields in coming days. In this review, we try to compile the existing knowledge on coal-derived nanoparticles/nanominerals and discuss the advanced level of characterization techniques for future research. This review also provides some of aspects of health risks associated with exposure to ambient nanoparticles. In addition, the presence of some of the hazardous elements in coal and coal combustion activities is also reviewed.

关键词： Coal combustion Nanoparticles Nanominerals Hazardous elements Human health Coal energy challenge

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