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Effect of roselle calyx extract on in vitro viability and biofilm formation ability of oral pathogenic bacteria

Asian Pacific Journal of Tropical Medicine 2016年第2期9卷 115-120页

作者： Herastuti Sulistyani mari.Fujita Hiroshi Miyakawa Futoshi Nakazawa Department of Oral Microbiology School of Dentistry Health Sciences University of Hokkaido

Objective: To investigate the effect of the roselle calyx extract(RCE)(Hibiscus sabdariffa L.) on the in vitro viability and biofilm formation ability of oral pathogenic bacteria. Methods:RCE was prepared by soaking roselle calyx powder with ethyl alcohol for 24 h at room temperature. After centrifugation, the extract was lyophilized. Then, the extract was dissolved in phosphate-buffered saline, the p H was adjusted, and the extract was aseptically filtered. We used Streptococcus mutans, Streptococcus sanguinis, lactobacillus casei, Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in this study. The antibacterial activity of the RCE was determined by treating the cells of these bacteria with the extract for 10 or 20 min at room temperature. The minimum inhibitory concentration(MIC) and minimum bactericidal concentration was determined using the micro dilution method, and the effect of the RCE on the ability to form biofilm was determined using a polystyrene micro plate assay. In addition, we used the WST-1 assay to determine the cytotoxicity of the RCE on HGF, Ca9-22 and KB cells. Results: The RCE had antibacterial activity against oral bacteria used in this study. In particular, most significant antibacterial activity was observed against Fusobacterium nucleatum, Prevotella intermedia and Porphyromonas gingivalis. The MIC and minimum bactericidal concentration were 7.2 mg/m L–28.8 mg/m L and 14.4 to >57.6 mg/m L. The RCE had an inhibitory effect on biofilm formation at the MIC and sub-MIC levels. In addition, the RCE had low cytotoxic effects on HGF, Ca9-22 and KB cells. Conclusions: Thus, our results indicate that the RCE may be used for preventing oral diseases.

关键词： Oral bacteria Oral biofilm Oral cells Roselle calyx extract

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Microstructure, Mechanical Properties and Wear Behaviourof Deep-Cryogenic-Treated HSS

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材料热处理学报 2004年第5期25卷 540-545页

作者： V. Leskovek M. Kalin J. vi■intin Institute of Metals and Technology Ljubljana SloveniaUniversity of Ljubljana Center for Tribology and Technical Diagnostics Ljubljana SloveniaUniversity of Ljubljana Center for Tribology and Technical Diagnostics Ljubljana Slovenia

In this paper we compare the wear behaviour of a vacuum-heat-treated ESR AISI M2 high-speed steel and the same steel that was vacuum heat treated in conjunction with a deep-cryogenic treatment at -196 °C. Four different tempering temperatures for the specimens austenized at the same austenitizing temperature were carefully selected to obtain various in-advance-determined combinations of the microstructures, the fracture toughness, KIc and the Rockwell-C hardness. Each of the eight specimens was therefore characterised by these microstructures and resulting material properties. The wear study was performed using a reciprocating sliding device under well-controlled contact conditions. Relatively high loads were used to provide enough wear for a comparison of the selected samples. A much harder and dissimilar model counter-material, i.e. silicon nitride ceramic, was used in order to avoid excessive wear of the counter samples and adhesion, which could occur in contacts with similar materials (metals/steels) under such high loads and in non-lubricated conditions. The wear behaviours were then compared and discussed in terms of these microstructures and the related properties. The differences in the wear resistance obtained in our investigation were as high as an order of magnitude. However, the beneficial effects are not a direct result of the type of the treatment, but relate to a proper combination of the resulting fracture toughness and the hardness. The more uniform and moderate values, which, however, tend to be obtained with a deep-cryogenic treatment, are beneficial to the high wear resistance of the selected high-speed steel.

关键词：高速钢显微结构深低温处理机械性质磨损性能

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The Janus face of N-terminal lysines in α-synuclein

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Neural Regeneration Research 2020年第10期15卷 1840-1841页

作者： Ana Belén Uceda laura mari.o Miquel Adrover Institut Universitari d’Investigació en Ciències de la Salut (IUNICS) Institut d’Investigació Sanitària Illes Balears (Id ISBa) Departament de Química Universitat de les Illes Balears

Parkinson’s disease(PD)is the second most prevalent progressive neurodegenerative disorder after Alzheimer’s *** usually starts with a tremor in the extremities(usually in the hands)and gradually evolves with other symptoms such as bradykinesia,muscle stiffness,impaired posture,loss of automatic movements or speech *** symptoms worsen as the condition progresses and eventually lead to death.

关键词： impaired Alzheimer eventually

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The Impact of Topography on Social Factors,a Case Study of Montenegro

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Journal of Mountain Science 2014年第1期11卷 131-141页

作者： TELBISZ Tamás BOTTLIK Zsolt mari.László KOSZEGI Margit Department of Physical Geography Eotvos University Department of Regional Science Eotvos University

Relationships between environmental and social factors have long been studied by ***,GIS-aided statistical analysis provides new tools to explore these *** order to detect the impact of topography on social factors,we selected the country of Montenegro as a case example due to its high topographic *** compared the spatial pattern of population,settlements and ethnic minorities to physical geographic factors,especially to topography,but lithology and land cover data were also taken into *** found that certain factors are closely correlated,*** settlement density linearly decreases with elevation,while the characteristic settlement area shows an exponential increase *** population density is not related to absolute elevation,but it is in close correlation with height(*** relative to the local minimum).Population change and illiteracy are also topography-related social *** the contrary,the variable ethnic pattern of Montenegro is influenced by historical,political and economic effects rather than by environmental factors or topographic *** a conclusion we state that in the scale of a country or a region,the environment can strongly impact some social factors.

关键词： Human-environment relations Dinarides GIS Settlements Population Ethnic groups

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Degradable magnesium-hydroxyapatite interpenetrating phase composites processed by current assisted metal infiltration in additive-manufactured porous preforms

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Journal of Magnesium and Alloys 2022年第12期10卷 3641-3656页

作者： mari.no Casas-Luna Edgar B.Montufar Norbert Hort Sebastian Díaz-de-la-Torre JoséClaudio Méndez-García Lucie vištejnová Adam Brínek AlešDanhel Karel Dvorak Jozef Kaiser ladislav Celko Central European Institute of Technology Brno University of TechnologyPurkynova 123Brno 61200Czech Republic Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Straße 1Geesthacht 21502Germany Institute of Product and Process Innovation Leuphana University LüneburgUniversitätsallee 1Lüneburg 21335Germany Centro de Investigación e Innovación Tecnológica Instituto Politécnico NacionalCerrada de Cecati s/nMexico City 02250Mexico Biomedical Center Faculty of Medicine in PilsenCharles UniversityAlej Svobody 1655/76Plzen 32300Czech Republic Institute of Biophysics of the Czech Academy of Sciences Královopolská135Brno 61265Czech Republic Faculty of Civil Engineering Brno University of TechnologyPurkynova 139Brno 61200Czech Republic

This work explores ceramic additive manufacturing in combination with liquid metal infiltration for the production of degradable interpenetrating phase magnesium/hydroxyapatite(Mg/HA) composites. Material extrusion additive manufacturing was used to produce stoichiometric,and calcium deficient HA preforms with a well-controlled open pore network, allowing the customization of the topological relationship of the composite. Pure Mg and two different Mg alloys were used to infiltrate the preforms by means of an advanced liquid infiltration method inspired by spark plasma sintering, using a novel die design to avoid the structural collapse of the preform. Complete infiltration was achieved in 8 min, including the time for the Mg melting. The short processing time enabled to restrict the decomposition of HA due to the reducing capacity of liquid Mg. The pure Mg-base composites showed compressive yield strength above pure Mg in cast state. Mg alloy-based composites did not show higher strength than the bare alloys due to grain coarsening, but showed similar mechanical properties than other Mg/HA composites that have significantly higher fraction of metallic phase. The composites showed faster degradation rate under simulated body conditions than the bare metallic component due to the formation of galvanic pairs at microstructural level. Mg dissolved preferentially over HA leaving behind a scaffold after a prolonged degradation period. In turn, the fast production of soluble degradation products caused cell metabolic changes after 24 h of culture with not-diluted material extracts. The topological optimization and reduction of the degradation rate are the topics for future research.

关键词： Interpenetrating phase composite Biodegradable metal Topological relationship Direct ink writing Metal infiltration Computed aided design

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Cesium＇s Affects on Morphological Changes of Human Erythrocytes

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Chinese Journal of Chemistry 2012年第2期30卷 427-432页

作者： Feng,Yunxiao la,Ming Chemistry and Chemical Engineering Department Pingdingshan UniversityPingdingshanHenan 467000China

Cesium could play a toxic role in several pathological processes. Atomic force microscopy （AFM） was used to study morphological changes of human erythrocytes after incubating with different concentrations of CsCI, and the Raman spectra were used to study the effects of CsCl on the chemistry components of erythrocyte membrane. The AFM images showed that the ＂domain structures＂ that appeared after incubation with higher concentration of CsCl （150 mmol-L-1）, are featured by the particles aggregated to form ranges and the separations among them enlarged to gorges, and this change may increase the permeability of cell membranes. The Raman results showed that the polar part of membrane phospholipid become more order and with the increasing of the concentration of CsCl, the longitudinal order of nonpolar parts first decreased and then increased. It is concluded that the aggregation of mem- brane proteins and the order changes of the phospholipid cause a change in the distribution and conformation of the phospholipid membrane. And the effects of CsCl on the erythrocyte membrane are mainly dependent on its concentration.

关键词： cesium human erythrocytes membrane domain structure AFM Raman spectroscopy

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Rifaximin discontinuation during broad-spectrum antibiotic treatment in critically ill patients with hepatic encephalopathy

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World Journal of Hepatology 2024年第11期16卷 1356-1360页

作者： Lorenzo Ridola Alessandro mari Department of Medical and Surgical Sciences and Biotechnologies Sapienza University of RomePolo PontinoRome 00185Italy

Hepatic encephalopathy(HE)is one of the main complications of cirrhosis,characterized by a wide spectrum of neuropsychiatric alterations that lead to an increase in mortality,morbidity and recurrent *** to the central role in HE pathogenesis of ammonia and other neurotoxins primari.y produced by the gut microbiota,the main therapeutic approaches for the treatment of HE are based on the modulation of the gut *** is a non-absorbable broad-spectrum antibiotic,that is effective against ammonia-producing grampositive,gram-negative,and anaerobic species,approved for the treatment of HE in secondary *** chronic administration of rifaximin in this setting is associated with a lower risk of HE recurrence and mortality,while the role of rifaximin for the treatment of an overt-HE episode in inpatients is still *** data exist about the coadministration of rifaximin and broad-spectrum antibiotics commonly used to treat concomitant infections,as patients receiving or recently treated with antibiotics were frequently excluded from clinical *** this editorial we comment on the article by Ward et al published in the recent issue of the World Journal of *** is a single center,retrospective,quasiexperimental,pharmacist-driven protocol,with the aim to evaluate the feasibility and safety of rifaximin discontinuation in critically ill patients with HE and chronic liver disease receiving broad-spectrum antibiotic therapies in intensive care *** study revealed no differences between the protocol and control group in terms of primary outcome(days alive and free of delirium and coma to day 14)and secondary outcomes which include:Intensive care mortality,intensive care length of stay,intravenous vasopressor requirement changes and adverse effects ***,rifaximin discontinuation during broad-spectrum antibiotic therapy does not appear to negatively impact the clinical status of critically ill liver patient

关键词： Hepatic encephalopathy Rifaximin discontinuation Broad-spectrum antibiotics Critically ill patients Intensive care unit

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Analysis of structural response under blast loads using the coupled SPH-FEM approach

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1184-1192页

作者： Jun-xiang XU Xi-la LIU Department of Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

A numerical model using the coupled smoothed panicle hydrodynamics-finite element method （SPH-FEM） approach is presented for analysis of structures under blast loads. The analyses on two numerical cases, one for free field explosive and the other for structural response under blast loads, are performed to model the whole processes from the propagation of the pressure wave to the response of structures. Based on the simulation, it is concluded that this model can be used for reasonably accurate explosive analysis of structures. The resulting information would be valuable for protecting structures under blast loads.

关键词： Smoothed particle hydrodynamics (SPH) Finite element method (FEM) Reinforced concrete structure Explosion

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Dominant edge direction based fast intra mode decision in the H.264/AVC encoder

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 767-777页

作者： Byeongdu la Minyoung EOM Yoonsik CHOE Department of Electrical and Electronic Engineering Yonsei University

The H.264/AVC video coding standard uses an intra prediction mode with 4×4 and 16×16 blocks for luma and 8×8 blocks for chroma. This standard uses the rate distortion optimization (RDO) method to determine the best coding mode based on the compression performance and video quality. This method offers a large improvement in coding efficiency compared to other compression standards, but the computational complexity is greater due to the various intra prediction modes. This paper proposes a fast intra mode decision algorithm for real-time encoding of H.264/AVC based on the dominant edge direction (DED). The DED is extracted using pixel value summation and subtraction in the horizontal and vertical directions. By using the DED, three modes instead of nine are chosen for RDO calculation to decide on the best mode in the 4×4 luma block. For the 16×16 luma and the 8×8 chroma, only two modes are chosen instead of four. Experimental results show that the entire encoding time saving of the proposed algorithm is about 67% compared to the full intra search method with negligible loss of quality.

关键词： H 264 Intra prediction Mode decision Dominant edge direction

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Stakeholders’power in the networking structuration processes of the urban resilience concept in Habitat III agenda(2012-2016)

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Geography and Sustainability 2022年第1期3卷 46-57页

作者： Daniela mari.o Céline Rozenblat Institute of Geography and Sustainability Faculty of GeosciencesUniversity of LausanneLausanne 1015Switzerland

The urban resilience concept was introduced in 2016 as a key concept in the Habitat III New Urban Agenda for the next 20 *** wonder how this urban resilience concept was elaborated and who influenced it the most?The preparatory events structured several stakeholders’*** relations between stakeholders allowed the flow of ideas in the consultation and production *** influential stakeholders strongly oriented definition of urban resilience concepts by taking power in the networking process of the consecutive *** paper analyzes the network of stakeholders/concepts,during the building process between 2012 and 2016(5,539 discourses from 290 stakeholders,in 357 events).The application of textual mining and machine learning topic modelling algorithm exposed the structure of the principal topics for building the concept of urban resilience,and presented how relations of main stakeholders with funders was crucial for the investment in policy ***,we underlined for the first time in an empirical way,different kinds of actors’power in the construction process that supported the Habitat III resilience *** demonstrated how far some official stakeholders,but also external and private ones,oriented the construction of ideologies to validate the knowledge that supported the related actions in laboratory cities.

关键词： Urban resilience Cities Habitat III Urban agenda Networks of power Global

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