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Neuronal activity controls the development of interneurons in the somatosensory cortex

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Frontiers in Biology 2016年第6期11卷 459-470页

作者： rachel Babij Natalia De Marco Garcia Center for Neurogenetics Brain and Mind Research Institute Weill Cornell Medical College New York NY 10065 USA Weill Cornell/Rockefeller/Sloan Kettering Tri-lnstitutional MD-PhD Program New York USA

BACKGROUND： Neuronal activity in cortical areas regulates neurodevelopment by interacting with defined genetic programs to shape the mature central nervous system. Electrical activity is conveyed to sensory cortical areas via intracortical and thalamocortical neurons, and includes oscillatory patterns that have been measured across cortical regions. OBJECTIVE： In this work, we review the most recent findings about how electrical activity shapes the developmental assembly of functional circuitry in the somatosensory cortex, with an emphasis on intemeuron maturation and integration. We include studies on the effect of various neurotransmitters and on the influence of thalamocortical afferent activity on circuit development. We additionally reviewed studies describing network activity patterns. METHODS： We conducted an extensive literature search using both the PubMed and Google Scholar search engines. The following keywords were used in various iterations：＂intemeuron＂, ＂somatosensory＂, ＂development＂, ＂activity＂, ＂network patterns＂, ＂thalamocortical＂, ＂NMDA receptor＂, ＂plasticity＂. We additionally selected papers known to us from past reading, and those recommended to us by reviewers and members of our lab. RESULTS： We reviewed a total of 132 articles that focused on the role of activity in interneuronal migration, maturation, and circuit development, as well as the source of electrical inputs and pattems of cortical activity in the somatosensory cortex. 79 of these papers included in this timely review were written between 2007 and 2016. CONCLUSIONS： Neuronal activity shapes the developmental assembly of functional circuitry in the somatosensory cortical interneurons. This activity impacts nearly every aspect of development and acquisition of mature neuronal characteristics, and may contribute to changing phenotypes, altered transmitter expression, and plasticity in the adult. Progressively changing oscillatory network patterns contribute to this activity in the earl

关键词： interneuron neurodevelopment neuroplasticity thalamocortical NMDA receptors neuronal maturation

Analysis of residual crosslinking agent content in UV cross-linked poly(ethylene oxide) hydrogels for dermatological application by gas chromatography

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Journal of Pharmaceutical Analysis 2016年第5期6卷 307-312页

作者： rachel Shet Hui Wong Mark Ashton Kalliopi Dodou Department of Pharmacy Health and Wellbeing Faculty of Applied Sciences University of Sunderland Science Complex

Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), *** assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels.

关键词： Poly(ethylene oxide) (PEO) Residual monomer HydrogelGas chromatography–mass spectrometry (GC–MS) Gas chromatography–flame ionization detection (GC–FID)

Research on Prostate MRI Segmentation with Random Walker and GAN

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Research on Prostate MRI Segmentation with Random Walker and...

作者： Nubwimana rachel 河北工业大学

学位级别：硕士

前列腺癌是男性第二常见的恶性肿瘤,仅次于肺癌,在发达国家的发病率更高。前列腺癌早期可能无症状,病程缓慢,只有在癌症进展时才会出现症状。因此,如果早发现、早诊断、早治疗,治愈率可以大大提高。前列腺癌的诊断和治疗主要采用MRI图... 详细信息

前列腺癌是男性第二常见的恶性肿瘤,仅次于肺癌,在发达国家的发病率更高。前列腺癌早期可能无症状,病程缓慢,只有在癌症进展时才会出现症状。因此,如果早发现、早诊断、早治疗,治愈率可以大大提高。前列腺癌的诊断和治疗主要采用MRI图像检测技术,其中许多问题包括腹部MRI中前列腺的准确性和自动分割,这对临床应用至关重要。目前,大多数现有的前列腺分割方法都是通过一系列的程序进行的,每一步都需要手动经验参数调整,且存在分割效率低和精度低等问题,为此,研究有利于计算机辅助诊断、适用于有限样本图像集的全自动算法是非常有意义的。此外,由于存在腺体边界模糊,分割不足或过度等问题,以及大数据处理的需要,研究前列腺MRI图像分割的深度学习方法非常必要,尤其是生成性对抗网络(GAN)由于其灵活的结构和强大的功能,已逐渐应用于各种图像处理任务。为此,本论文针对上述问题开展了以下工作。(1)基于随机游走算法的前列腺MRI图像分割研究。为解决分割效率低、轮廓不完整、分割泄漏和偏差大等问题,并适应于有限的图像集和全自动处理,提出一种改进的随机游走算法,即多图谱RW进行图像分割,其算法步骤如下:选择具有可见前列腺轮廓的切片,生成其真值(正确的标注值),用于图谱和多图谱生成。在此过程中,真值图像被采样成相同的像素大小和图像大小,然后,所有真值图像被叠加到一个单独的图像空间中。在堆叠过程之后,在该图像空间中生成概率图,并选择两个概率级别来提取内部种子(前景种子)和外部种子(背景种子)。生成的种子被作为随机行走算法的自动种子。通过实验分析,将提出的多图谱RW与图谱RW的和基本RW进行比较,并使用形状相似性进行评估,平均Dice相似系数(DSC)分别为0.72、0.62和0.52,平均Jaccard相似系数(JSC)分别为0.71、0.62和0.54。同样使用距离和体积差进行评估,Hausdorff距离(H)分别为4.87、5.93和5.89,相对体积差(RVD)分别为0.36、0.48和0.57。研究结果表明提出的多图谱RW是切实可行且行之有效的。(2)基于生成对抗网络(GAN)的前列腺MRI图像分割研究。为克服腺体边界模糊,前列腺内组织的异质性导致的分割不足或过度,以及患者或病理学之间的生理差异等问题,并适应于大数据图集处理,提出一种基于端到端深度学习生成对抗网络(GAN)的前列腺分割模式(PGAN),其任务是区分结构分割过程中使用的真值掩模和分割掩模,具有EM距离的生成对抗网络(GAN)进行像素级语义分割。然后将PGAN模式应用于四种不同的GAN结构,即带有基本鉴别器的PGAN、带有早期融合网络的PGAN、带有回归网络的PGAN和带有乘积网络的PGAN。在实验分析中,使用Dice相似系数(DSC)、Jaccard相似系数、相对体积差异(RVD)和Hausdorff距离(H)等多种指标对前列腺分割进行比较,并在一个数据集上进行评估,该数据集包含493个磁共振成像作为训练数据,98个磁共振成像作为实验测试数据。研究结果表明,所提出的带回归网络的PGAN的DSC平均值为0.97,JSC平均值为0.97,RVD平均值为0.01,H平均值为2.93。显然,它优于基本GAN和随机Walker等分割方法,是一种适合大数据处理的分割方法。

关键词：磁共振图像前列腺图像分割随机行走算法生成对抗网络

BRCA mutated pancreatic cancer:A change is coming

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World Journal of Gastroenterology 2021年第17期27卷 1943-1958页

作者： Michael N Rosen rachel A Goodwin Michael M Vickers Faculty of Medicine The University of OttawaOttawa K1H 8L6OntarioCanada The Ottawa Hospital Cancer Center The University of OttawaOttawa K1H 8L6OntarioCanada

Pancreatic cancer remains a leading cause of cancer-related death with few available therapies for advanced ***,patients with germline BRCA mutations have received increased attention due to advances in the management of BRCA mutated ovarian and breast *** BRCA mutations significantly increase risk of developing pancreatic cancer and can be found in up to 8%of patients with sporadic pancreatic *** patients with germline BRCA mutations,platinum-based chemotherapies and poly(ADP-ribose)polymerase inhibitors are effective treatment options which may offer survival *** review will focus on the molecular biology,epidemiology,and management of BRCA-mutated pancreatic ***-more,we will discuss future directions for this area of research and promising active areas of research.

关键词： Pancreatic cancer Systemic therapy Platinum chemotherapy BRCA Deoxyribonucleic acid repair Poly(ADP-ribose)polymerase inhibitors

Molecular recognition and specificity of biomolecules to titanium dioxide from molecular dynamics simulations

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npj Computational Materials 2020年第1期6卷 1390-1397页

作者： Janani Sampath Andrew Kullman rachel Gebhart Gary Drobny Jim Pfaendtner Physical Sciences Division Pacific Northwest National LaboratoryRichlandWAUSA Department of Chemical Engineering University of WashingtonSeattleWAUSA Department of Chemistry University of WashingtonSeattleWAUSA

Titania(TiO_(2))is used extensively in biomedical applications;efforts to boost the biocompatibility of TiO_(2) include coating it with the titania binding hexamer,*** understand the binding mechanism of this peptide,we employ molecular dynamics simulations enhanced by metadynamics to study three amino acids present in the peptide—arginine(R),lysine(K),and aspartate(D),on four TiO2 variants that have different degrees of surface hydroxyl groups.

关键词： dynamics titanium dioxide

Intravitreal aflibercept in neovascular age-related macular degeneration previously treated with ranibizumab

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International Journal of Ophthalmology(English edition) 2017年第3期10卷 423-426页

作者： rachel Hui Fen Lim Bhaskar Gupta Peter Simcock Royal Devon and Exeter NHS Foundation Trust BarrackRoad Exeter EX2 5DW United Kingdom

AIM：To report the change in visual acuity and central macular thickness（CMT）following treatment with intravitreal aflibercept injections in patients with neovascular agerelated macular degeneration（n AMD）with suboptimum response to ***：This was a retrospective study. The inclusion criteria were patients with n AMD who responded poorly to ranibizumab. Patients then received either 3 consecutive aflibercept injections followed by pro re nata（PRN）treatment or PRN alone. Primary endpoints were mean change in bestcorrected visual acuity（BCVA）and CMT at 12 mo. Secondary endpoints were number of injections and adverse ***：Forty-nine eyes from 49 patients met the inclusion criteria and completed 12-month follow up on aflibercept. Thirty-eight eyes received 3 consecutive aflibercept injections followed by PRN treatment and 11 eyes received PRN injections alone. At 12 mo,mean BCVA improved by one letters（log MAR 0.56±0.31 to 0.54±0.34）and mean CMT decreased from 303.9±82.1 to 259.2±108.3 μ*** percent of eyes gained 15 letters or more,6% lost more than 15 letters and the remaining 90% had stable BCVA. The mean number of aflibercept injections was *** was one case of infectious ***：Intravitreal aflibercept in patients with n AMD with a previous suboptimal response to ranibizumab resulted in an anatomical improvement in macular appearance at 12 mo without a corresponding improvement in visual acuity.

关键词： aflibercept ranibizumab neovascular agerelated macular degeneration

Use of rifaximin in gastrointestinal and liver diseases

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World Journal of Gastroenterology 2016年第29期22卷 6638-6651页

作者： Rani H Shayto rachel Abou Mrad Ala I Sharara Division of Gastroenterology Department of Internal Medicine American University of Beirut Medical Center

Rifaximin is a broad spectrum oral antibiotic with antimicrobial activity against Gram-positive and Gram-negative aerobic and anaerobic bacteria. It is poorly absorbed and thus has a highly favorable safety profile. Rifaximin has been shown to be effective in the treatment of traveler’s diarrhea, functional bloating and irritable bowel syndrome, small bowel bacterial overgrowth and in the prevention of recurrent overt hepatic encephalopathy. In addition, there is emerging evidence for a possible beneficial effect of rifaximin in the treatment of uncomplicated diverticular disease and in the prevention of recurrent diverticulitis. The use of rifaximin is associated with a low incidence of development, or persistence of spontaneous bacterial mutants. Moreover, the development of important drug resistance among extra-intestinal flora during rifaximin therapy is unlikely because of minimal systemic absorption and limited cross-resistance of rifaximin with other antimicrobials. This review addresses the current and emerging role of rifaximin in the treatment of gastrointestinal and liver disorders.

关键词： Irritable bowel syndrome Inflammatory bowel disease Hepatic encephalopathy Bacterial overgrowth Diverticular disease

Incorporating novelty and novel ecosystems into restoration planning and practice in the 21st century

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Ecological Processes 2013年第1期2卷 175-182页

作者： Michael P Perring rachel J Standish Richard J Hobbs Ecosystem Restoration and Intervention Ecology Research Group School of Plant BiologyThe University of Western Australia35 Stirling HighwayCrawleyWA 6009Australia

Novelty pervades the *** some cases,potentially irreversible abiotic and/or biotic changes have led to the crossing of thresholds and thus the formation of“novel ecosystems.”Their widespread emergence(particularly on land)and the presence of continued environmental change challenge a traditional restoration goal of restoring an historical ***,we argue that restoration could broaden its frame of reference to consider how novel ecosystems might be used to maintain global biodiversity and provide ecosystem services and,in doing so,save potentially wasted efforts in attempting to fulfil traditional *** we explore this contention in more depth by addressing:Are novel ecosystems innovative planning or lowering the bar?We show that novel ecosystems were not innovative planning in their original *** the contrary,they were recognized as ecosystems that were recalcitrant to traditional restoration approaches,coupled with an awareness that they had arisen inadvertently through deliberate human activity,either on-or *** recalcitrance to traditional restoration suggests that alternative goals may exist for these ecosystems using sometimes innovative *** management may include biodiversity conservation or restoration for ecological *** elucidate the latter aspect with reference to an experiment in the wheatbelt of Western Australia—The Ridgefield Multiple Ecosystem Services Experiment—the design of which has been informed by ecological theory and the acceptance of novelty as an ecosystem *** novel ecosystems do provide opportunities to broaden restoration planning and practice,and ultimately maintain and conserve global biodiversity in this era of environmental change,they necessarily“lower the bar”in restoration if the bar is considered to be the historical ***,in these times of flux,such a bar is increasingly ***,careful and appropriate interventions are required

关键词： No-analogue ecosystem Biodiversity conservation Ecosystem function Ecological restoration Restoration baseline Ridgefield multiple ecosystem services experiment York gum woodland

Effect of Niobium on Transformations From Austenite to Ferrite in Low Carbon Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 208-212页

作者： Parker Sally Rose Andrew West Geoff Thomson rachel Steel Metallurgy Department Tata Steel RD and TSwinden Technology CentreRotherhamS60 3ARUK Department of Materials Loughborough UniversityLoughboroughLE11 3TUUK

Niobium has an important effect on the transformation behaviour,grain size refinement and precipitation strengthening during hot rolling and subsequent cooling in low carbon steels,with even a low content of niobium having a strong effect on the transformation rate from austenite to ***,the effects of niobium on transformation behaviour have not been fully characterised and understood to *** paper examines in detail austenite grain growth as a function of austenitisation time in high strength low alloy (HSLA) steels with three different niobium contents,together with the effect of niobium on the isothermal transformation kinetics from austenite to ferrite as a function of *** is shown that austenite has the slowest grain growth rate in the steel with the highest niobium *** austenite grain sizes are consistent,the steel with the highest niobium content was found to have the slowest transformation rate from austenite to ferrite.

关键词： niobium transformation kinetics austenite grain growth low carbon steels