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101篇 您的检索式:作者名="Helen N"
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1Multispecies probiotic protects gut barrier function in experimental models显示文摘AIM:To investigate the effect of the probiotic combination Lactibiane Tolerance?(LT)on epithelial barrier function in vitro and in vivo.METHODS:The effect of the multispecies probiotic LT was assessed on several models of epithelial barrier function both in vitro(in basal and inflammatory conditions)and in vivo[visceral hypersensitivity induced by chronic stress or by colonic perfusion of a fecal supernatant(FSN)from patients with irritable bowel syndrome(IBS)].In vitro,we measured the permeability of confluent T84 cell monolayers incubated with or without LT by evaluating the paracellular flux of macromolecules,in basal conditions and after stimulation with lipopolysaccharide(LPS)or with conditioned medium of colonic biopsies from IBS patients(IBS-CM).In vivo,male C57/Bl6 mice received orally NaCl or LT for 15 d and were submitted to water avoidance stress(WAS)before evaluating visceral sensitivity by measuring the myoelectrical activity of the abdominal muscle and the paracellular permeability with 51Cr-EDTA.Permeability and sensitivity were also measured after colonic instillation of FSN.Tight-junctions were assessed by immunoblotting and TLR-4 expression was evaluated by immunohistochemistry RESULTS:Incubation of T84 cell monolayers with LT in basal conditions had no significant effect on permeability(P>0.05 vs culture medium).By contrast,addition of LT bacterial bodies(LT)completely prevented the LPS-induced increase in paracellular permeability(P<0.01 vs LPS 10 ng/mL(LPS 10);P<0.01 vs LPS 100ng/mL(LPS 100),P>0.05 vs culture medium).The effect was dose dependent as addition of 109 LT bacterial bodies induced a stronger decrease in absorbance than 106 LT(109 LT+LPS 10:-20.1%±13.4,P<0.01vs LPS 10;106 LT+LPS 10:-11.6%±6.2,P<0.01 vs LPS 10;109 LT+LPS 100:-14.4%±5.5,P<0.01 vs LPS 100;106 LT+LPS 100:-11.6%±7.3,P<0.05 vs LPS 100).Moreover,the increase in paracellular permeability induced by culturing T84 cells with conditioned medium of colonic biopsies from IBS patients(IBS-CM)was completely inhibited in the presence of 109 LT(P<0.01 vs IBS-CM).LT also significantly prevented the epithelial disruption induced by intracolonic infusion of fecal supernatant from IBS patients(P<0.01 vs IBS FSN)or water avoidance stress P<0.01 vs WAS)in C57/Bl6 mice and increased the expression of occludin in vitro and in vivo,as assessed by immnunoblotting.The WAS-induced effect on visceral sensitivity was prevented by LT treatment since values obtained for all steps of colorectal distension were significantly(P<0.01)different from the WAS group.Finally,LT downregulated the response mediated through TLR-4 in vitro(decrease in tumor necrosis factorαsecretion in response to LPS:-65.8%for 109 LT and-52.5%for 106LT,P<0.01 vs LPS)and in vivo(inhibition of WAS induced an increase in TLR-4 expression in the LT treated mice colon,P<0.01 vs WAS).CONCLUSION:The probiotic LT mix prevented the disruption to the epithelial barrier induced by LPS,stress or colonic soluble factors from IBS patients and prevented visceral hypersensitivity.Mylene Nébot-Vivinus Cherryl Harkat Hanene Bzioueche Christel Cartier Raffaella Plichon-Dainese Lara Moussa Helene Eutamene Dorsa Pishvaie Sophie Holowacz Christian Seyrig Thierry Piche Vassilia Theodorou 2014World Journal of Gastroenterology2014,20,22:12
2虚拟现实技术应用于神经心理评估的研究概述显示文摘传统神经心理评估的实验控制和生态效度的平衡问题日益受到研究人员的关注,而新兴的虚拟现实(Virtual Reality,VR)技术为问题的改善带来了希望,它不仅可以模拟现实环境并支持被试的直接交互,而且能对传统测试进行再现和扩展。它所形成的评估系统能对刺激的内容和表象、任务的复杂度和被试的响应进行灵活控制,所获取的信息更丰富、准确。在初步评估注意过程(注意、单侧空间忽略)、记忆(前瞻记忆、情景记忆、空间记忆、地形定向)和执行功能方面已获得了令人满意的效果。然而目前VR评估的应用仍存在技术和设备方面的不足,以及对评估者和被试不同操作要求的局限,因此今后除了要规范化现有VR评估系统,还应该进一步发展基础条件来推动系统的广泛应用。郑霞 SAUZEON Helene 周明全 N'KAOUA Bernard 2010心理科学进展2010,18,3:11
3Counter-regulatory phosphatases TNAP and NPP1 temporally regulate tooth root cementogenesis显示文摘Cementum is critical for anchoring the insertion of periodontal ligament fibers to the tooth root. Several aspects of cementogenesis remain unclear, including differences between acellular cementum and cellular cementum, and between cementum and bone.Biomineralization is regulated by the ratio of inorganic phosphate(Pi) to mineral inhibitor pyrophosphate(PPi), where local Piand PPi concentrations are controlled by phosphatases including tissue-nonspecific alkaline phosphatase(TNAP) and ectonucleotide pyrophosphatase/phosphodiesterase 1(NPP1). The focus of this study was to define the roles of these phosphatases in cementogenesis. TNAP was associated with earliest cementoblasts near forming acellular and cellular cementum. With loss of TNAP in the Alpl null mouse, acellular cementum was inhibited, while cellular cementum production increased, albeit as hypomineralized cementoid. In contrast, NPP1 was detected in cementoblasts after acellular cementum formation, and at low levels around cellular cementum. Loss of NPP1 in the Enpp1 null mouse increased acellular cementum, with little effect on cellular cementum.Developmental patterns were recapitulated in a mouse model for acellular cementum regeneration, with early TNAP expression and later NPP1 expression. In vitro, cementoblasts expressed Alpl gene/protein early, whereas Enpp1 gene/protein expression was significantly induced only under mineralization conditions. These patterns were confirmed in human teeth, including widespread TNAP, and NPP1 restricted to cementoblasts lining acellular cementum. These studies suggest that early TNAP expression creates a low PPienvironment promoting acellular cementum initiation, while later NPP1 expression increases PPi, restricting acellular cementum apposition. Alterations in PPihave little effect on cellular cementum formation, though matrix mineralization is affected.Laura E Zweifler Mudita K Patel Francisco H Nociti Jr Helen F Wimer Jose L Milln Martha J Somerman Brian L Foster 2015International Journal of Oral Science2015,7,1:5
4Apple dwarfing rootstocks exhibit an imbalance in carbohydrate allocation and reduced cell growth and metabolism显示文摘Apple dwarfing rootstocks cause earlier shoot termination and reduced root and shoot mass.To identify physiological factors responsible for rootstock-induced growth restriction,we compared vascular-enriched gene expression between two dwarfing rootstocks(‘M27’and‘M9’)and the vigorous rootstock‘M793’using RNA sequencing and quantitative reverse transcriptase PCR.Differentially expressed genes common to both dwarfing rootstocks belonged to five main biological processes:(1)primary metabolism,(2)cell wall synthesis and modification,(3)secondary metabolism,(4)hormone signalling and response and(5)redox homeostasis.Genes promoting the biosynthesis of amino acids,lipids and cell walls were downregulated in dwarfing rootstocks,whereas genes promoting the breakdown of these compounds were upregulated.The only exception to this trend was the upregulation of starch synthesis genes in dwarfing rootstocks.Non-structural carbohydrate analysis demonstrated that starch concentrations in‘M9’roots,stems and grafted‘Royal Gala’(‘RG’)scions were double that of equivalent tissues from‘RG’homo-grafted trees(‘RG’/‘RG’).Fructose and glucose concentrations were much lower in all three tissues of the‘RG’/‘M9’trees.Together,these data indicate that dwarfing rootstocks are in a state of sugar depletion and reduced cellular activity despite having large starch reserves.Another significant finding was the over-accumulation of flavonoids and the downregulation of auxin influx transporters MdAUX1 and MdLAX2 in dwarfing rootstocks.We propose that both factors reduce polar auxin transport.The results of this study contribute novel information about the physiological state of dwarfing rootstocks.Toshi M Foster Peter A McAtee Chethi N Waite Helen L Boldingh Tony K McGhie 2017Horticulture Research2017,4,1:4
5Causes of encephalitis and differences in their clinical presentations in England: a multicentre, population-based prospective study显示文摘Julia Granerod Helen E Ambrose Nicholas WS Davies Jonathan P Clewley Amanda L Walsh Dilys Morgan Richard Cunningham Mark Zuckerman Ken J Mutton Tom Solomon Katherine N Ward Michael PT Lunn Sarosh R Irani Angela Vincent David WG Brown Natasha S Crowcroft 2010The Lancet Infectious Diseases2010,,12:2
6Positive darwinian selection after gene duplication in primate ribonuclease genes显示文摘ZHANG J HELENE F R MASATOSHI N 1998Proc Natl Acad Sci USA1998,95,:1
7Primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes in the Collaborative Atorvastatin Diabetes Study (CARDS): multicentre randomised placebo-controlled trial显示文摘Helen M Colhoun D John Betteridge Paul N Durrington Graham A Hitman H Andrew W Neil Shona J Livingstone Margaret J Thomason Michael I Mackness Valentine Charlton-Menys John H Fuller 2004The Lancet . 2004 (9435)2004,,9435:1
8Theoretical analysis of the incompressible laminar flow in a macro-roughness cell显示文摘Arghir M Roucou N Helene M 2003ASME J Tribol2003,125,:1
9Cryopreserved-thawedembryo transfer in natural or down-regulated hormonallycontrolled cycles: aretrospectivestudy 显示文摘Tarek G Luciano N Helen H 2006Fertil Steril2006,85,3:1
10A novel method for producing anti-peptide antibodies显示文摘POSNETYZ David N MCGRATH Helen TAM James P 1988The Journal of Biological Chemistry1988,263,4:1
11Performance prediction and its use in parallel and distributed computing systems显示文摘Stephen A Jarvis Daniel P Spooner Helene N Lim Choi Keung 2006Future Generation Computer Systems2006,22,7:1
12High-performance liquid chromatographic resolution of NADP - after induction of fluorescence and its application to assay for an NADPH-dependent enzyme: application to the determination of glutathione reductase activity in p/ant leaf extracts显示文摘Helen A N Pillai P 1996Anal Biochem1996,237,1:1
13Further improvement of the critical charge model for the theoretical evaluation of the breakdown voltage of conductor bundle-toplane gaps显示文摘Alexandrov G N Podporkyn G V Helene Menemenlis 1980IEEE Trans on Power Apparatus and Systems1980,99,2:1
14Glycation compounds in peanuts显示文摘Welllner A Lena N Helen T 2012European Food Research and Technology2012,234,3:1
15Association Between Use of β-Blockers and Prostate Cancer–Specific Survival: A Cohort Study of 3561 Prostate Cancer Patients with High-Risk or Metastatic Disease显示文摘Helene Hartvedt Grytli Morten Wang Fagerland Sophie D. Foss? Kristin Austlid Taskén 2013European Urology2013,,:1
16Treatment of dextran sulfate sodium-induced murine colitis by intracolonic cyclosporin 显示文摘S N S Murfliy Harry S Cooper Helen Shim 1993Dig Dis Sci1993,38,9:1
17Determination of chloramphenicol residues in meat, seafood, egg, honey * milk, plasma and urine with liquid chromatography-tandem mass spectrometry, and the validation of the method based on 2002/657/EC显示文摘Helene T R Kristin E Tone N A 2006Journal of chromatography A2006,1118,:1
18Unsupervised synthetic aperture radar image segmentation using Fisher distribution显示文摘PREDERIC G JEAN-MARIE N HELENE S 2009IEEE Tran on Geoscience and Remote Sensing2009,47,8:1
19Role of lycopene in recovery of radiation induced injury to mammalian cellular organelles显示文摘Saada Helen N Azab Khaled S 2001Pharmazie2001,56,3:1
20Antiapoptotic effects of IGF-1 and PDGF on human intervertebral disc cell in vitro显示文摘Helen E Gruber H James N 0,,:1
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