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Transforming growth factor-β1 induces intestinal myofibroblast differentiation and modulates their migration

World Journal of Gastroenterology 2009年第12期15卷 1431-1442页

作者： Julia Brenmoehl sandra nicole miller Claudia Hofmann Daniela Vogl Werner Falk Jrgen Schlmerich Gerhard Rogler Department of Internal Medicine Ⅰ University of Regensburg93055 Regensburg Germany Department of Internal Medicine Ⅱ University of Jena07747 Jena Germany Clinic of Gastroenterology and Hepatology Department of Internal MedicineUniversity Hospital of Zurich8091 ZurichSwitzerland

AIM:To investigate the effects of transforming growth factorβ1(TGF-β1)on the differentiation of colonic lamina propria fibroblasts(CLPF)into myofibroblasts in vitro. METHODS:Primary CLPF cultures were incubated with TGF-β1 and analyzed for production ofα-smooth muscle actin(α-SMA),fibronectin(FN)and FN *** assays were performed in a modified 48-well Boyden *** of total and phosphorylated focal adhesion kinase(FAK)in CLPF were analyzed after induction of ***:Incubation of CLPF with TGF-β1 for 2 d did not changeα-SMA levels,while TGF-β1 treatment for 6 d significantly increasedα-SMA production. Short term incubation(6 h)with TGF-β1 enhanced CLPF migration,while long term treatment(6 d)of CLPF with TGF-β1 reduced migration to 15%-37% compared to untreated *** and FN isoform mRNA expression were increased after short term incubation with TGF-β1(2 d)in contrast to long term incubation with TGF-β1 for 6 *** induction of migration, TGF-β1-preincubated CLPF showed higher amounts of FN and its isoforms and lower levels of total and phosphorylated FAK than untreated cells. CONCLUSION:Long term incubation of CLPF with TGF-β1 induced differentiation into myofibroblasts with enhancedα-SMA,reduced migratory potential and FAK phosphorylation,and increased FN *** contrast,short term contact(6 h)of fibroblasts with TGF-β1 induced a dose-dependent increase of cell migration and FAK phosphorylation without induction ofα-SMA production.

关键词：转化生长因子细胞分化移民成纤维细胞生长因子平滑肌肌动蛋白 FAK磷酸化 Boyden小室肌纤维母细胞

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Forage production and persistence characteristics of grazed native warm-season grass mixtures with or without nitrogen fertilizer

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Grassland Research 2022年第3期1卷 157-165页

作者： Caroline nicole Chappell Marty Landon Marks Katie Michelle Mason Liliane Severino da Silva Joshua Luke Jacobs Mary Kimberly Mullenix sandra Leanne Dillard Russell Brian Muntifering Department of Animal Sciences Auburn UniversityAuburnAlabamaUSA Department of Animal Science University of TennesseeKnoxvilleTennesseeUSA Department of Animal and Veterinary Sciences Clemson UniversityClemsonSouth CarolinaUSA University of Kentucky Cooperative Extension Service CarlisleKentuckyUSA

Background:Native warm-season grass(NWSG)mixtures may provide a lownitrogen(N)-input summer perennial forage option to extensively managed forage-livestock ***:Mixed pastures of big bluestem(Andropogon gerardii Vitman),little bluestem(Schizachyrium scoparium Michx.),and indiangrass(Sorghastrum nutans L.)fertilized with 0 or 67 kgNha−1 were continuously stocked with beef heifers and *** mass,nutritive value,and canopy heights were determined every 2 weeks during the grazing *** persistence measures included the canopy cover and leaf area index(LAI)and plant crown density at spring emergence following 3 years of grazing ***:Forage mass,canopy height,and stocking densities were greater for N-fertilized NWSG than unfertilized NWSG for the first 30 days of the growing season across the 3-year *** NWSG fertilized with N had a greater decrease in LAI during the growing season(51%decrease)than unfertilized *** NWSG plant density estimates following 3 years of grazing did not differ across N management ***:Forage NWSG mixtures supported superior forage attributes and greater stocking densities early in the grazing season under low-level N than zero-N-input systems and may provide a low-N-input alternative for improved species use in southeastern US forage-livestock systems.

关键词： continuous stocking grazing native warm-season grass mixtures nitrogen fertilization

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Verteporfin synergizes the efflcacy of anti-PD-1 in cholangiocarcinoma

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Hepatobiliary & Pancreatic Diseases International 2022年第5期21卷 485-492页

作者： Jianyang Fu nicole A McGrath Jihye Lee Xin Wang Gagandeep Brar Changqing Xie Thoracic and Gastrointestinal Malignancies Branch Center for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesdaMD 20892USA sandra and Edward Meyer Cancer Center Weill Cornell MedicineNew YorkNY 10065USA

Background:Cholangiocarcinoma(CCA)is one of the primary hepatobiliary malignant neoplasms with only 10%of 5-year survival *** immunotherapy with the blockade of immune checkpoints has no clear benefit in *** inhibition of YAP1 signaling by verteporfin has shown encouraging results by inhibiting cell proliferation and inducing *** study aimed to evaluate the potential benefit of the combination of verteporfin and anti-programmed cell death 1(PD-1)in CCA mouse ***:We assessed the cytotoxicity of verteporfin in human CCA cell lines in vitro,including both intrahepatic CCA and extrahepatic CCA *** examined the in vitro effect of verteporfin on cell proliferation,apoptosis,and *** evaluated the in vivo efflcacy of verteporfin,anti-PD-1,and a combination of both in subcutaneous CCA mouse ***:Our study showed that verteporfin reduced tumor cell growth and enhanced apoptosis of human CCA tumor cells in vitro in a dose-dependent ***,verteporfin impaired stemness evidenced by reduced spheroid formation and colony formation,decreased numbers of cells with aldehyde dehydrogenase activity and positive cancer stem cell markers(all P<0.05).The combination of verteporfin and anti-PD-1 reduced tumor burden in CCA subcutaneous SB1 tumor model compared to either agent ***:Verteporfin exhibits antitumor effects in both intrahepatic and extrahepatic CCA cell lines and the combination with anti-PD-1 inhibited tumor growth.

关键词： Verteporfin YAP1 Anti-programmed cell death-1 Immunotherapy Cholangiocarcinoma

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基于特征学习的校园场景识别与定位

基于特征学习的校园场景识别与定位

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作者： UMURUNGI sandra nicole 北京交通大学

学位级别：硕士

计算机视觉是一门跨学科的科学领域,涉及计算机如何从数字图像中获得高级理解。从工程学的角度来看,它试图理解人类视觉系统可以完成的任务并通过编程的方式实现。计算机视觉任务包括用于获取、处理、分析、理解数字图像和提取可产生数... 详细信息

计算机视觉是一门跨学科的科学领域,涉及计算机如何从数字图像中获得高级理解。从工程学的角度来看,它试图理解人类视觉系统可以完成的任务并通过编程的方式实现。计算机视觉任务包括用于获取、处理、分析、理解数字图像和提取可产生数字或符号形式的决策信息的高维数据的方法。场景识别是机器人和计算机视觉应用的基本问题,而学习特征是计算机视觉的一个重要技术,它是允许系统从原始数据中自动发现特征检测或分类所需的表示形式的技术。本研究的校园场景识别和定位的基本特征学习是属于图像定位领域的,对图像中的物体进行定位、摄像机拍摄的场景图像的定位与识别又是计算机视觉领域的一项任务,也是解决识别问题的第一步。现有的研究说明了场景识别和分类定位的重要性。本文采取了五种不同的行为方式,如鼓掌,拳击,挥手,投掷和步行。使用HOG＆SIFT等特征检测技术,并在支持向量机上训练,最终给出了准确的结果。基于图像定位的目的是从单一的查询图像中检索出感兴趣区域内摄像机的姿态（方位和位置）,并显示出可识别的目标位置,本研究的目标是通过使用摄像机拍摄各个建筑物不同角度的照片,来对这些位置进行定位。本文使用了一种对图像预处理的方法,目的是去除不必要的信息,帮助模型有效地学习图像的特征,从而提高了精度。本文还介绍了图像预处理的几种方法,包括调整图像大小、创建图像像素阵列和数据采集、去除图像中的背景噪声。特征提取对正确检测目标具有重要作用,本文提出了一种基于兴趣的局部特征提取方法用于检测图像中的关键点,该方法通过计算该点周围区域的方向梯度（HOG）直方图,并用尺度不变特征变换（SIFT）提取特征,该变换包括四个主要阶段:尺度空间的极值检测、特征点定位、特征方向赋值和特征点描述。为了评价本研究提出方法的性能,使用一组新的测试图像预测其类别,并给出位置预测的准确性。将支持向量机（SVM）算法用于特征提取后的图像分类。支持向量机是一组用于分类的监督式学习方法,适用于广义线性分类。支持向量机的特点是,它能同时最小化经验分类误差和最大化几何边缘区,因此支持向量机（SVM）被称为最大边缘区分类器。支持向量机将输入向量映射到一个高维特征空间,在该空间中构造一个最大分离超平面,在分离超平面的每一侧构造两个平行超平面,分离超平面是使两个平行超平面之间的距离最大化的超平面。这些平行超平面之间的差距或距离越大,则说明分类器的泛化误差就越小,论文的最后在对常见评估指标进行了比较的基础上,我们将混淆矩阵用于评估本研究提出方法的性能。混淆矩阵是一个表格,通常用于描述一个分类模型在一组已知真实值的测试数据上的性能。它允许可视化算法的性能,并显示分类模型在进行预测时被混淆的部分。本研究首先介绍了所使用的数据集,并对数据集进行了预处理,然后对数据进行提取特征,最后将每幅图像对应的特征组合成不同类别的分类图像用于场景识别。由于定义场景识别是计算机视觉的一项里程碑式的任务,因此可以定义用于对象识别的上下文。该方法同时利用图像的全局特征描述符、局部特征描述符以及对应于每个图像的描述符,从每幅图像中提取与检测到的关键点相对应的尺度不变特征变换（SIFT）特征。本研究主要利用sklimage库（scikit图像）进行特征提取。对应于图像中的每个关键点,都存在一个尺度不变的特征变换描述符,其尺寸由参数步长（描述符采样点之间的距离）和半径（描述扫描区域的尺寸）控制。本研究还提取了一个与不同粒度的整个图像相对应的标准方向梯度（HOG）描述子直方图（利用像素/单元、单元/块和方向的参数）,该直方图允许我们选择不同尺度的特征。实验采用标准支持向量机（SVM）分类器进行场景识别。我们利用sckit-learn（sklearn）库来实现支持向量机,通过将数据集随机分成训练集和测试集来进行交叉验证,并从划分的训练集中构造训练特征向量。最后我们通过得到的总体准确性、混淆矩阵以及标准信息检索数据,如精确率、召回率和F值来评价本研究提出的方法的性能。我们收集了北京交通大学收集的数据,将各个建筑的地标作为该地点的标志位置,在每组中构建了53组用于场景识别的建筑地标图像,其中包含了该建筑地标在不同角度的更多图像。然后将用于场景识别的数据集分为两类（训练和测试）,通过随机选择训练集和测试集,得到了特、场景识别和定位技术上的实验结果。最后我们可以在数据集中检索图像进行场景匹配,并分析了实例级地标匹配对场景识别等影响定位精度的因素。在本研究的实验中使用python编写来实现特征提取和分类器模型。实验实现了从所有训练图像中提取的尺度不变特征变换（SIFT）描述子。在单用尺度不变特征变换（SIFT）描述子时,分类准确率为76%,平均准确率为76%,平均召回率为75%,平均F1分数为71%。在只使用方向梯度直方图（HOG）时的分类准确率为56%,平均准确率为61%,

关键词：学习特征提取特征场景识别场景分类

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Prepartum dietary energy intake alters adipose tissue transcriptome profiles during the periparturient period in Holstein dairy cows

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Journal of Animal Science and Biotechnology 2020年第2期11卷 410-423页

作者： Andrea Minuti Massimo Bionaz Vincenzo Lopreiato nicole A.Janovick sandra L.Rodriguez-Zas James K.Drackley Juan J.Loor Department of Animal Sciences Food and NutritionFaculty of AgricultureFood and Environmental ScienceUniversitàCattolica del Sacro Cuore29122 PiacenzaItaly Animal and Rangeland Sciences Oregon State UniversityCorvallisOR 97330USA Department of Animal Sciences Division of Nutritional SciencesUniversity of IllinoisUrbanaIL 61801USA

Background:The aim of the study was to investigate the effect of energy overfeeding during the dry period on adipose tissue transcriptome profiles during the periparturient period in dairy ***:Fourteen primiparous Holstein cows from a larger cohort receiving a higher-energy diet(1.62 Mcal of net energy for lactation/kg of dry matter;15%crude protein)for ad libitum intake to supply 150%(OVR)or 100%(CTR)of energy requirements from dry off until parturition were *** calving,all cows received the same lactation *** adipose tissue(SAT)biopsies were collected at−14,1,and 14d fromparturition(d)and used for transcriptome profiling using a bovine oligonucleotide *** mining of differentially expressed genes(DEG)between treatments and due to sampling time was performed using the Dynamic Impact Approach(DIA)and Ingenuity Pathway Analysis(IPA).Results:There was a strong effect of over-feeding energy on DEG with 2434(False discovery rate-corrected P<0.05)between OVR and CTR at−14 d,and only 340 and 538 at 1 and 14 *** most-impacted and activated pathways in the Kyoto Encyclopedia of Genes and Genomes(KEGG)database that were highlighted by DIA analysis at−14 d in OVR *** included 9 associated with carbohydrate metabolism,with‘Pyruvate metabolism’,‘Glycolysis/gluconeogenesis’,and‘Pentose phosphate pathway’among the *** surprisingly,OVR led to marked activation of lipid metabolism(e.g.‘Fatty acid biosynthesis’and‘Glycerolipid metabolism’).Unexpected metabolic pathways that were activated at−14 d in OVR included several related to metabolism of amino acids(*** chain)and of cofactors and vitamins(thiamin).Among endocrine and immune system pathways,at−14 d OVR led to marked activation of‘PPAR signalling’and‘Antigen processing and presentation’.Among key pathways affected over time in OVR,a number were related to translation(*** signaling),endocrine/immune signaling(CXCR4 and IGF1),and lipid metabolism(oxidative

关键词： Periparturient cow Prepartum overfeeding Subcutaneous adipose tissue Transcriptome

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