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Growth factor-and cytok.ne-driven pathways governing liver stemness and differentiation

World Journal of Gastroenterology 2010年第41期16卷 5148-5161页

作者： aránzazu sánchez Isabel Fabregat school of Pharmacy Complutense University 28040 Madrid Spain Bellvitge Biomedical Research Institute (IDI- BELL) and University of Barcelona Molecular Oncology Laboratory Hospital Duran i Reynals. Gran Via de Hospitalet 199 L' Hospitalet 08907 Barcelona Spain

Liver is unique in its capacity to regenerate in response to injury or tissue loss. Hepatocytes and other liver cells are able to proliferate and repopulate the liver. However, when this response is impaired, the contribution of hepatic progenitors becomes very relevant. Here, we present an update of recent studies on growth factors and cytok.ne-driven intracellular pathways that govern liver stem/pro-genitor cell expansion and differentiation, and the rel-evance of these signals in liver development, regeneration and carcinogenesis. Tyrosine k.nase receptor signaling, in particular, c-Met, epidermal growth factor receptors or fibroblast growth factor receptors, contribute to prolifera-tion, survival and differentiation of liver stem/progenitor cells. Different evidence suggests a dual role for the trans-forming growth factor (TGF)-β signaling pathway in liver stemness and differentiation. On the one hand, TGF-βmediates progression of differentiation from a progenitor stage, but on the other hand, it contributes to the expan-sion of liver stem cells. Hedgehog family ligands are nec-essary to promote hepatoblast proliferation but need to be shut off to permit subsequent hepatoblast differentiation. In the same line, the Wnt family and β-catenin/T-cell fac-tor pathway is clearly involved in the maintenance of liver stemness phenotype, and its repression is necessary for liver differentiation during development. Collectively, data indicate that liver stem/progenitor cells follow their own rules and regulations. The same signals that are essential for their activation, expansion and differentiation are good candidates to contribute, under adequate conditions, to the paradigm of transformation from a pro-regenerative to a pro-tumorigenic role. From a clinical perspective, this is a fundamental issue for liver stem/progenitor cell-based therapies.

关键词： Hepatocyte growth factor Epidermal growth factor Fibroblast growth factor Transforming growth factor-β Hedgehog and β-catenin Liver stem cell

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Pharmacologically tested aldose reductase inhibitors isolated from plant sources—A concise report

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中国天然药物 2012年第5期10卷 388-400页

作者： D. k. Patel R. k.mar k. sairam s. Hemalatha Pharmacognosy Research Laboratory Department of Pharmaceutics Institute of Technology Banaras Hindu University

Aldose reductase (ar), a cytosolic, monomeric oxidoreductase, is a k.y enzyme in the polyol pathway which controls the conversion of glucose to sorbitol. The accumulation of sorbitol by the activation of ar enzymes in lens, retina, and sciatic nerves leads to the cause of diabetic defects resulting in various secondary complications, viz. retinopathy, neuropathy, nephropathy and Alzheimer's disease. Thus, reduction of the polyol pathway flux by ar inhibitors could be a potential therapeutic opening in the treatment and prevention of diabetic complications. At present, the ar inhibitors belong to two different chemical classes. One is the hydantoin derivatives, such as sorbinil, Dilantin, and Minalrestat, and the other is the carboxylic acid derivatives, such as Epalrestat, Alrestatin, and Tolrestat. However, it is k.own that most of these synthethic compounds have unacceptable side-effects. Well k.own medicinal plants lik. Chrysanthemum indicum, Chrysanthemum morifolium, Prunus mume, Myrcia multiflora, Centella asiatica, and salacia reticulata, salacia oblonga, and salacia chinensis exhibited potent ar inhibitory activity. The present review summarizes the list of plant material, and their isolated phytoconstituents which have been tested for their ar inhibitory activity. This litreature review covers the period to 2011, and a total of 72 plants are listed.

关键词： Aldose reductase Cataracts Enzyme Human recombinant ar Medicinal plants Phytoconstituents Polyol pathway Rat lens ar Rat lens

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Fine mapping and identification of candidate genes for the peach powdery mildew resistance gene Vr3

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Horticulture Research 2020年第1期7卷 343-351页

作者： Neus Marimon Jordi Luque Pere arús Iban Eduardo Centre for Research in Agricultural Genomics(CRAG)CsIC-IRTA-UAB-UB Campus UAB08193 BellaterraBarcelonaSpain IRTA(Institut de Recerca i Tecnologia Agroalimentàries) BarcelonaSpain Plant Pathology IRTA CabrilsCarretera de Cabrils km 208348 CabrilsSpain

Powdery mildew is one of the major diseases of peach(Prunus persica),caused by the ascomycete Podosphaera ***,it is controlled through calendar-based fungicide treatments starting at petal fall,but an alternative is to develop resistant peach *** studies mapped a resistance gene(Vr3)in interspecific populations between almond(‘Texas’)and peach(‘Earlygold’).To obtain molecular mark.rs highly link.d to Vr3 and to reduce the number of candidate genes,we fine-mapped Vr3 to a genomic region of 270 k. with 27 annotated *** find evidence supporting one of these positional candidate genes as being responsible of Vr3,we analyzed the polymorphisms of the resequences of both parents and used near-isogenic lines(NILs)for expression analysis of the positional candidate genes in symptomatic or asymptomatic *** differentially expressed between resistant and susceptible individuals were annotated as a Disease Resistance Protein RGA2(Prupe2G111700)or an Eceriferum 1 protein involved in epicuticular wax biosynthesis(Prupe2G112800).Only Prupe2G111700 contained a variant predicted to have a disruptive effect on the encoded protein,and was overexpressed in both heterozygous and homozygous individuals containing the Vr3 almond allele,compared with susceptible *** information was also useful to identify and validate molecular mark.rs tightly link.d and flank.ng *** addition,the NILs used in this work.will facilitate the introgression of this gene into peach elite materials,alone or pyramided with other k.own resistance genes such as peach powdery mildew resistance gene Vr2.

关键词： resistance peach mapping

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Photolysis studies on HCOOH and HCOO^- in presence of TiO_2 photocatalyst as suspension in aqueous medium

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Journal of Natural Gas Chemistry 2009年第1期18卷 50-54页

作者： G. R. Dey k. N. R. Nair k. k. Pushpa Radiation and Photochemistry Division Bhabha Atomic Research Centre Trombay Mumbai 400 085 India

Photolysis studies on formic acid （HCOOH） and formate ion （HCOO-） in presence of TiO2, a photocatalyst, as suspension in water were carried out separately using 350 nm ultraviolet light. The products, such as H2, CO, CO2 and CH4, generated during the experiments were monitored with varying the ambient, light exposure time, and the concentration of HCOOH/HCOO-. The yields of CO in all these systems increased with light exposure time. In aerated systems, CO yields were higher in contrast to the deoxygenated （ar-purged） systems under identical conditions. It is proposed apparently that the formation of CO is tak.ng place during the chemical reduction of in-situ generated CO2, a photo-mineralized product of HCOOH/HCOO-, but not through the direct photodecomposition or photodehydration （CO＋H2O） of solute molecules. The rates of CO formation during 1.3 M HCOOH photolysis in presence of TiO2 photocatalyst were evaluated to be 0.21 and 0.13 μl/min in aerated and ar-purged systems, respectively. As compared with HCOOH systems, the CO yields are lower when 0.2 M HCOONa was exposed to light under identical conditions. The CO growth rates were evaluated to be 0.07 and 0.046 μl/min^-1 for aerated and deoxygenated HCOONa systems, respectively; moreover, the trend is quite similar to that of the HCOOH system. Under these conditions, the emission of H2 was also observed, and its yield was significantly higher in ar-purged system as compared with the CO yields. However, in aerated system, the yields of these products were just opposite. The formation of low yield of methane was observed during photolysis of HCOOH/HCOO ions. In CO2 ambient, the yields of CO and H2 varied drastically with time.

关键词： formic acid formate ion photolysis TiO2

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Immunohistochemical analysis of p53,cyclinD1,RB1,c-fos and N-ras gene expression in hepatocellular carcinoma in Iran

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World Journal of Gastroenterology 2007年第4期13卷 588-593页

作者： sJ Moghaddam EN Haghighi s samiee N shahid ar k.ramati s Dadgar MR Zali Research Center for Gastroenterology and Liver Disease Shaheed Beheshti University of Medical Sciences and Academy of Medical Sciences Iran

AIM： TO study the effect of some genes especially those involved in cell cycle regulation on hepatocellular carcinoma. METHODs： Paraffin-embedded tissue samples of 25 patients （18 males and 7 females） with hepatocellular carcinoma were collected from 22 pathology centers in Tehran during 2000-2001, and stained using immunohistochemistry method （avidin-biotin-peroxidase） for detection of p53, cyclinD1, RB1, c-los and N-ras proteins. REsULTs： six （24%）, 5 （20%）, 12 （48%） and 2 samples （8%） were positive for p53, cyclinDl, C-los and N-ras expression, respectively. Twenty-two （88%） samples had alterations in the （31 cell-cycle check.oint protein expression （RBI or cyclinD1）. P53 positive samples showed a higher （9 times） risk.of being positive for RBI protein than p53 negative samples. Loss of expression of RBI in association with p53 over-expression was observed in 4 （66.7%） of 6 samples. Loss of expression of RBI was seen in all cyclinD1 positive, 20 （90.9%） N-ras negative, and ii （50%） C-fos positive samples, respectively. CyclinD1 positive samples showed a higher （2.85 and 4.75 times） risk.of being positive for c-los and N-ras expression than cyclinD1 negative samples. CONCLUsION： The expression of p53, RB1 and c-los genes appears to have a k.y role in the pathogenesis of hepatocellular carcinoma in Iran. simultaneous overexpression of these genes is significantly associated with their loss of expression during development of hepatocellular carcinoma.

关键词： Hepatocellular Carcinoma Iran Expressionof p53, cyclinD1, RB1, c-fos and N-ras genes

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A comprehensive survey of augmented reality assembly research

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Advances in Manufacturing 2016年第1期4卷 1-22页

作者： X. Wang s. k. Ong A. Y. C. Nee Graduate school for Integrative sciences and Engineering National University of Singapore 28 Medical DriveSingapore 117456 Singapore Department of Mechanical Engineering Faculty ofEngineering National University of Singapore9 Engineering Drive 1 Singapore 117576 Singapore

In the past two decades, augmented reality （ar） has received a growing amount of attention by researchers in the manufacturing technology community, because ar can be applied to address a wide range of problems throughout the assembly phase in the lifecycle of a product, e.g., planning, design, ergonomics assessment, operation guidance and training. However, to the best of authors＇ k.owledge, there has not been any comprehensive review of ar-based assembly systems. This paper aims to provide a concise overview of the technical features, characteristics and broad range of applications of ar- based assembly systems published between 1990 and 2015. Among these selected articles, two thirds of them were published between 2005 and 2015, and they are considered as recent pertinent work. which will be discussed in detail. In addition, the current limitation factors and future trends in the development will also be discussed.

关键词： Augmented reality (ar) Assembly processAssembly guidance Assembly systems

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Cylinder Pressure Prediction of An HCCI Engine Using Deep Learning

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Chinese Journal of Mechanical Engineering 2021年第2期34卷 160-167页

作者： Halit Yaşar Gültek.nÇağıl Orhan Tork.l MerveŞişci Department of Mechanical Engineering Engineering FacultySakarya UniversityEsentepe Campus54187 SerdivanSakaryaTurkey Department of Industrial Engineering Engineering FacultySakarya UniversityEsentepe Campus54187 SerdivanSakaryaTurkey

Engine tests are both costly and time consuming in developing a new internal combustion ***,it is of great importance to predict engine characteristics with high accuracy using artificial ***,it is possible to reduce engine testing costs and speed up the engine development *** Learning is an effective artificial intelligence method that shows high performance in many research areas through its ability to learn high-level hidden features in data *** present paper describes a method to predict the cylinder pressure of a Homogeneous Charge Compression Ignition(HCCI)engine for various excess air coefficients by using Deep Neural Network.which is one of the Deep Learning methods and is based on the artificial Neural Network.ANN).The Deep Learning results were compared with the ANN and experimental *** results show that the difference between experimental and the Deep Neural Network.DNN)results were less than 1%.The best results were obtained by Deep Learning *** cylinder pressure was predicted with a maximum accuracy of 97.83%of the experimental value by using *** the other hand,the accuracy value was increased up to 99.84%using *** results show that the DNN method can be used effectively to predict cylinder pressures of internal combustion engines.

关键词： artificial neural network Deep neural network HCCI engine Cylinder pressure Excess air coefficient

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spatial analysis and structure of a cross-timber stand in the TallGrass Prairie Preserve (Pawhusk., Ok.ahoma)

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Journal of Forestry Research 2013年第1期24卷 47-52页

作者： José Ramón arévalo Departamento de Ecología Facultad de BiologíaUniversidad de La LagunaLa Laguna 38206Spain

I analyzed the spatial distribution and structure of trees in a cross timber forest in the Tallgrass Prairie Preserve （Pawhusk., Ok.ahoma, UsA）. I mapped and measured diameter of all stems, saplings （〉1.5 m tall） and dead trees in a 4-ha plot. The stand was dominated by Quercus stellata and Q. marilandica. In total, I mapped 7,636 trees, consisting of 6,785 Q. stellata, 846 Q. marilandica, 2 Celtis occidentalis, 1 Fraxinus pensilvanica and 2 Prunus americana. For saplings, I mapped 54 Q. stellata and 21 Q. marilandica. The size class distribution of the two dominant species did not differ. The dominant mortality class was “standing dead”, while I only found saplings less than 2 m tall. The spatial distribution of the species indicated segregation in the use of the environment, generating a clumped univariate distribution of stems of the same species within radii of 30 m, but repulsion outside 30 m. This segregation can be explained by the different ecological requirements of each species.

关键词： conservation point pattern analysis Quercus stellata Q.marilandica size class distribution

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On the space bv_p(F) of sequences of p-bounded Variation of Fuzzy Numbers

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Acta Mathematica sinica,English series 2008年第7期24卷 1205-1212页

作者： zer TALO Feyzi BA■ar Fatih niversitesi Fen-Edebiyat FakltesiMatematik BlmBykekmece Kamps 34500-stanbulTrkiye

Recently, the space bvp of real or complex numbers consisting of all sequences whose differences are in the space lp has been studied by Basar, Altay [Uk.ainian Math. J. 55（1）（2003）, 136-147], where 1 ≤ p ≤ ∞. The main purpose of the present paper is to introduce the space bvp（F） of sequences of p-bounded variation of fuzzy numbers. Moreover, it is proved that the space bvp（F） includes the space lp（F） and also shown that the spaces bvp（F） and lp（F） axe isomorphic for 1 ≤ p ≤∞. Furthermore, some inclusion relations have been given.

关键词： sequence of fuzzy numbers space of difference sequences isomorphic spaces and inclusion relations

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Computational Prediction of Micro RNAs from Toxoplasma gondii Potentially Regulating the Hosts' Gene Expression

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Genomics, Proteomics & Bioinformatics 2014年第5期12卷 228-238页

作者： Müs?erref Duygu saar Caner Bagc? Jens Allmer Molecular Biology and Genetics Izmir Institute of Technology Urla Izmir 35430 Turkey Biotechnology Izmir Institute of Technology Urla Izmir 35430 Turkey Bionia Incorporated IZTEKGEB A8 Urla Izmir 35430 Turkey

MicroRNAs （miRNAs） were discovered two decades ago, yet there is still a great need for further studies elucidating their genesis and targeting in different phyla. since experimental discovery and validation of miRNAs is difficult, computational predictions are indispensable and today most computational approaches employ machine learning. Toxoplasma gondii, a parasite residing within the cells of its hosts lik. human, uses miRNAs for its post-transcriptional gene reg- ulation. It may also regulate its hosts＇ gene expression, which has been shown in brain cancer. since previous studies have shown that overexpressed miRNAs within the host are causal for disease onset, we hypothesized that T. gondii could export miRNAs into its host cell. We computationally predicted all hairpins from the genome of T. gondii and used mouse and human models to filter possible candidates. These were then further compared to k.own miRNAs in human and rodents and their expression was examined for T. gondii grown in mouse and human hosts, respectively. We found that among the millions of potential hairpins in T. gondii, only a few thousand pass filtering using a human or mouse model and that even fewer of those are expressed. since they are expressed and differentially expressed in rodents and human, we suggest that there is a chance that T. gondii may export miRNAs into its hosts for direct regulation.

关键词： Toxoplasma gondii MicroRNA Regulation Host interaction Parasite

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