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In vivo biofilm formation on stainless steel bonded retainers during different oral health-care regimens

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International Journal of Oral Science 2015年第1期7卷 42-48页

作者： Marije A Jongsma Henny C van der Mei Jelly Atema-Smit Henk J Busscher Yijin Ren Department of Orthodontics University of Groningen and University Medical Centre Department of Biomedical Engineering University of Groningen and University Medical Centre

Retention wires permanently bonded to the anterior teeth are used after orthodontic treatment to prevent the teeth from relapsing to pre-treatment positions. A disadvantage of bonded retainers is biofilm accumulation on the wires, which produces a higher incidence of gingival recession, increased pocket depth and bleeding on probing. This study compares in vivo biofilm formation on single-strand and multi-strand retention wires with different oral health-care regimens. Two-centimetre wires were placed in brackets that were bonded to the buccal side of the first molars and second premolars in the upper arches of 22 volunteers. Volunteers used a selected toothpaste with or without the additional use of a mouthrinse containing essential oils. Brushing was performed manually. Regimens were maintained for 1 week, after which the wires were removed and the oral biofilm was collected to quantify the number of organisms and their viability, determine the microbial composition and visualize the bacteria by electron microscopy. A 6-week washout period was employed between regimens. Biofilm formation was reduced on single-strand wires compared with multi-strand wires; bacteria were observed to adhere between the strands. The use of antibacterial toothpastes marginally reduced the amount of biofilm on both wire types, but significantly reduced the viability of the biofilm organisms. Additional use of the mouthrinse did not result in significant changes in biofilm amount or viability. However, major shifts in biofilm composition were induced by combining a stannous fluoride- or triclosan-containing toothpaste with the mouthrinse. These shifts can be tentatively attributed to small changes in bacterial cell surface hydrophobicity after the adsorption of the toothpaste components, which stimulate bacterial adhesion to the hydrophobic oil, as illustrated for a Streptococcus mutans strain.

关键词： antimicrobials biofilm bonded retention wires mouthrinse orthodontics

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The heterogeneity-diversity-system performance nexus

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National Science Review 2023年第7期10卷 251-260页

作者： Nico Eisenhauer Gerrit Angst Ana E.B.Asato Rémy Beugnon Elisabeth B?nisch Simone Cesarz Peter Dietrich Stephanie D.Jurburg Anna-Maria Madaj Rine C.Reuben Christian Ristok Marie Sünnemann Huimin Yi Carlos A.Guerra Jes Hines German centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig Institute of biology Leipzig University Institute of Soil biology and Biogeochemistry Biology Centre of the Czech Academy of Sciences Leipzig Institute for Meteorology Universit?t Leipzig CEFE Univ Montpellier CNRS EPHE IRD Department of Environmental Microbiology Helmholtz Centre for Environmental Research – UFZ

Ever-growing human population and nutritional demands,supply chain disruptions,and advancing climate change have led to the re alization that changes in diversity and system performance are intimately ***,diversity and system performance depend on *** changes in system performance and promoting sustainable living conditions requires transformative ***,we introduce the heterogeneity-diversity-system performance(HDP) nexus as the conceptual basis upon which to formulate transformative *** suggest that managing the heterogeneity of systems will best allow diversity to provide multiple benefits to *** on ecological theory,we pose that the HDP nexus is broadly applicable across systems,disciplines,and sectors,and should thus be considered in future decision making as a way to have a more sustainable global future.

关键词： heterogeneity diversity biodiversity-ecosystem functioning global change homogenization

An updated systematic review of Zika virus-linked complications

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Asian Pacific Journal of Tropical Medicine 2018年第1期11卷 1-8页

作者： Braira Wahid Amjad Ali Muhammad Waqar Muhammad Idrees centre for Applied Molecular biology University of the Punjab Genome centre for Molecular Based Diagnostics and Research centre Hazara University

Objective: To determine the breadth of Zika virus(ZIKV)-associated brain anomalies in neonates and adults. Methods: Systematic review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) statement using electronic databases ScienceDirect, Pubmed, Medline, Scopus, and Global Health *** those research articles, case studies, case-control studies, case-cohort studies, crosssectional studies, and organizational survey reports were included in the study that reported any fetal outcomes for pregnant women who had infected with ZIKV during the gestational period and ZIKV-related neurological complications in adults as well. Results: Out of total 72 retrieved articles, 50 met the inclusion criteria. We estimated a significant increase in incidence of neural abnormalities such as Guillain-Barre syndrome and microcephaly in the regions that are experiencing ZIKV outbreaks. Other neurological malformations found in ZIKV patients include hydrancephaly/hydrops fetalis, myasthenia gravis,meningoencephalitis and myelitis. Conclusion: Our systematic analysis provides the broad spectrum of neurological malformations in ZIKV infected patients and these data further support the causal link of ZIKV with neurological disorders.

关键词： Zika virus Microcephaly Guillain-Barre syndrome Acute myelitis Meningoencephalitis hydrancephaly/hydrops fetalis Myasthenia gravis

Using presence signs to discriminate between similar species

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Integrative Zoology 2009年第3期4卷 258-264页

作者： Sara M.SANTOS António P.MIRA Maria Luz MATHIAS centre of Environmental biology Department of Animal BiologyUniversity of LisbonLisbonPortugal and Institute of Mediterranean Agricultural Sciences Department of BiologyUniversity ofévoraévoraPortugal

The Lusitanian and the Mediterranean pine voles(Microtus lusitanicus Gerbe,1879 and Microtus duodecimcostatus de Selys-Longchamps,1839)are fossorial sister species and have an allopatric pattern of distribution in Portugal,which includes a potential sympatry area in the centre of the *** present study aimed to determine the validity of using presence signs in the field for discrimination of the two species in an area of sympatry(Northern Alentejo)and the characteristics that achieve the best classification accuracy.A total of 175 trapping plots were sampled across the study *** to the set up of traps,ten presence signs were randomly selected for measure-ments of four variables:proportion of soil mounds,mean diameter of mounds,proportion of burrow openings and mean diameter of burrow *** the basis of a classification tree analysis,results showed that presence signs can be used to discriminate plots inhabited by one or the other species in the studied sympatry *** character-istic that most accurately enables species identification is the proportion of burrow openings:for every ten pres-ence signs found in a plot,if more than eight have an opening,then it is inhabited by ***(*** burrow openings with few or no mounds present);if eight or fewer have an opening,*** is present(*** mounds with few or no burrow openings).

关键词： Microtus duodecimcostatus Microtus lusitanicus presence signs species identification.

Association of rare SPINK1 gene mutation with another base substitution in chronic pancreatitis patients

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World Journal of Gastroenterology 2006年第33期12卷 5352-5356页

作者： Viacheslav N Kalinin Jussuf T Kaifi Heidi Schwarzenbach Anatoly S Sergeyev Bjoern C Link Dean Bogoevski Yogesh Vashist Jakob R Izbicki Emre F Yekebas Department of General Visceral and Thoracic Surgery University Medical Center Hamburg-Eppendorf Hamburg Germany Institute for Tumor biology University Medical Center Hamburg-Eppendorf Hamburg Germany Research centre for medical Genetics Moscow Russia

AIM: To verify and expand the known spectrum of serine protease inhibitor Kazal type 1 (SPINK1) gene mutations in chronic pancreatitis. METHODS: DNA extracted from 172 chronic pancreatitis patients was assayed for SPINK1 gene mutations by PCR and DNA sequencing. A control cohort of 90 unrelated healthy individuals was analysed by the same methods for presence of common populational polymorphisms, and frequency of five-loci haplotypes was calculated. Linkages of gene aberrations in single SPINK1 gene copies were analysed by long-distance PCR followed by allele-specifi c PCR and DNA sequencing. RESULTS: The most frequent SPINK1 gene mutation N34S was found at a frequency of 6%. Furthermore, we detected the heterozygous intervening sequence (IVS) 3 + 2 T > C mutated gene in 2 German patients and 1 Macedonian chronic pancreatitis patient. In all three SPINK1 gene copies an additional rare base substitution was found: 5’untranslated region (UTR)-215 G > A. Poly-morphism analysis revealed that all three affected genes carried the same fi ve-loci haplotype. DNA sequencing of another chronic pancreatitis-related gene PRSS1 (cationic trypsinogen) did not reveal any mutations in these 3 ***: We found in 3 (2%) of 172 chronic pancreatitis patients an IVS3 + 2 T > C SPINK1 gene mutation and a base substitution 5’UTR-215 G > A inthe same gene copy. Most probably the 5’UTR-215 G >A represents a rare polymorphism and not a mutationas previously concluded. Haplotype analysis suggests acommon origin of the IVS3 + 2 T > C mutation in thesepatients.

关键词： Chronic pancreatitis Serine protease inhibitor Kazal type 1 Gene mutations

Three-dimensional size and orientation of the precipitates in AZ91 magnesium alloys measured by TEM techniques

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Chinese Physics B 2009年第10期18卷 4370-4379页

作者：郑鸥马家艳王建波周嘉萍金磊赵东山王仁卉 Department of Physics and Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education Wuhan University centre for electron Microscopy Wuhan University

Knowledge of the microscopic structure, including three-dimensional （3-D） size and orientation of the precipitates, is essential to fully understand the mechanical properties of the magnesium alloys and designing the alloys with better performance. Analytical TEM with high spatial resolution offers the simultaneous measurements of 3-D size, structure, orientation, composition of the precipitates from one typical sample along an established crystallographic axis. Besides popular Burgers orientation relationship （OR）, other ORs such as Pitsch-Schrader OR, Crawley OR, Potter OR and a new OR with the form of [0001]α 1.0° from [311]γ and （1120）α 2.0° from （033）γ between the magnesium matrix and the precipitate γ-MglTAl 12 are identified by TEM imaging and diffraction techniques. As a case study, the thicknesses of the individual precipitates with Burgers OR are further measured to be 100 200 nm through both electron energy-loss spectroscopy and x-ray energy dispersive spectroscopy combining differential x-ray absorption and extrapolation, which are in agreement with the overall 3-D size statistic distribution results obtained through analysing various samples along various directions. Furthermore, the fabricated wedge-shape structure provides a platform on which to study the dependence of the interfacial strain on the variation of the thickness.

关键词： transmission electron microscopy microstructure Mg electron energy loss spectroscopy

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The microbiota is dispensable for the early stages of peripheral regulatory T cell induction within mesenteric lymph nodes

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Cellular & Molecular Immunology 2021年第5期18卷 1211-1221页

作者： Carolin Wiechers Mangge Zou Eric Galvez Michael Beckstette Maria Ebel Till Strowig Jochen Huehn Joern Pezoldt Department Experimental Immunology Helmholtz Centre for Infection ResearchBraunschweigGermany Department Microbial Immune Regulation Helmholtz Centre for Infection ResearchBraunschweigGermany Department of Computational biology for Individualised Medicine Centre for Individualised Infection MedicineHelmholtz Centre for Infection Research and Hannover Medical SchoolHannoverGermany Cluster of Excellence RESIST(EXC 2155) Hannover Medical SchoolHannoverGermany Laboratory of Systems biology and Genetics École Polytechnique Fédérale de LausanneLausanneSwitzerland

Intestinal Foxp3+regulatory T cell(Treg)subsets are crucial players in tolerance to microbiota-derived and food-borne antigens,and compelling evidence suggests that the intestinal microbiota modulates their generation,functional specialization,and *** bacterial species and microbiota-derived metabolites,such as short-chain fatty acids(SCFAs),have been reported to promote Treg homeostasis in the intestinal lamina ***,gut-draining mesenteric lymph nodes(mLNs)are particularly efficient sites for the generation of peripherally induced Tregs(pTregs).Despite this knowledge,the direct role of the microbiota and their metabolites in the early stages of pTreg induction within mLNs is not fully ***,using an adoptive transfer-based pTreg induction system,we demonstrate that neither transfer of a dysbiotic microbiota nor dietary SCFA supplementation modulated the pTreg induction capacity of *** mice housed under germ-free(GF)conditions displayed equivalent pTreg induction within *** molecular characterization of these de novo induced pTregs from mLNs by dissection of their transcriptomes and accessible chromatin regions revealed that the microbiota indeed has a limited impact and does not contribute to the initialization of the Treg-specific epigenetic ***,our data suggest that the microbiota is dispensable for the early stages of pTreg induction within mLNs.

关键词： Peripheral regulatory T cells Microbiota Tolerance

Towards a multiscale model of colorectal cancer

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World Journal of Gastroenterology 2007年第9期13卷 1399-1407页

作者： Ingeborg MM van Leeuwen Carina M Edwards Mohammad Ilyas Helen M Byrne centre for Mathematical Medicine and biology School of Mathematical Sciences University of Nottingham Nottingham NG7 2RD United Kingdom centre for Mathematical biology Oxford Centre for Industrial and Applied Mathematics Mathematical Institute University of Oxford Oxford OX1 3LB United Kingdom Division of Pathology School of Molecular Medical SciencesQueen’s Medical Centre University of Nottingham Nottingham NG7 2UHUnited Kingdom

Colorectal cancer (CRC) is one of the best characterised cancers, with extensive data documenting the sequential gene mutations that underlie its development. Complementary datasets are also being generated describing changes in protein and RNA expression, tumour biology and clinical outcome. Both the quantity and the variety of information are inexorably increasing and there is now an accompanying need to integrate these highly disparate datasets. In this article we aim to explain why we believe that mathematical modelling represents a natural tool or language with which to integrate these data and, in so doing, to provide insight into CRC.

关键词： Intestinal epithelium Crypt fission APC mutations Mathematical modelling Stem cell niche Wnt signalling

A negative feedback loop controls ROS production in plant immunity

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Molecular Plant 2021年第8期14卷 1221-1222页

作者： Michael Wrzaczek Institute of Plant Molecular biology Biology CentreCzech Academy of Sciences37005 Ceske BudejoviceCzech Republic Organismal and Evolutionary biology Research Programme Viikki Plant Science CentreUniversity of Helsinki00014 HelsinkiFinland

Over the past two decades the view of reactive oxygen species(ROS)as merely cytotoxic compounds has changed considerably(Waszczak et al.,2018).While still being considered as reactive chemicals with potentially devastating detrimental effects,ROS have been shown to be used by plants and animals alike as messengers in numerous signaling networks,including responses to biotic and abiotic environmental cues as well as developmental processes(Waszczak et al.,2018;Zandalinas et al.,2020).

关键词： immunity chemicals numerous