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Punctual mutations in 23S rRNA gene of clarithromycinresistant Helicobacter pylori in Colombian populations

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World Journal of Gastroenterology 2018年第14期24卷 1531-1539页

作者： Andrés Jenuer Matta Diana Carolina Zambrano alvaro Jairo Pazos Registro Poblacional de Cáncer de Cali Department of Pathology School of Medicine Universidad del Valle Faculty of Education and Sports Sciences Institución Universitaria Escuela Nacional del Deporte Department of Biology Universidad de Nari?o

AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H. pylori) and determine their association with therapeutic *** PCR products of 23S rRNA gene V domain of 74 H. pylori isolates; 34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC) population: TumacoColombia, and 5 from a high-risk population: TuquerresColombia) and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres) were sequenced using capillary electrophoresis. The concordance between mutations of V domain 23S rRNA gene of H. pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H. pylori mutationsand clarithromycin ***23S rRNA gene from H. pylori was amplified in 56/74 isolates, of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres, respectively). In 17 resistant isolates(13 from Tumaco and 4 from Túquerres) the following mutations were found: A1593 T1, A1653 G2, C1770 T, C1954 T1, and G1827 C in isolates from Tumaco, and A2144 G from Túquerres. The mutations T2183 C, A2144 G and C2196 T in H. pylori isolates resistant to clarithromycin from Colombia are reported for the first time. No association between the H. pylori mutations and in vitro clarithromycin resistance was found. However, therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H. pylori(κ = 0.71).CONCLUSION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H. pylori.

关键词： Clarithromycin In vitro resistance Point mutation Helicobacter pylori Gastric cancer 23S rRNA

[As_(3)M(As_(3)Pb_(3))]^(3−)(M=Nb,Ta):Ternary Heterometallic Clusters with Early Transition Metal Atoms and Aromatic[Pb_(3)]^(2−)

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Chinese Journal of Chemistry 2021年第7期39卷 1953-1957页

作者： Cong-Cong Shu Lei Qiao alvaro Muñoz-Castro Zhong-Ming Sun Tianjin Key Lab for Rare Earth Materials and Applications State Key Laboratory of Elemento-Organic ChemistrySchool of Materials Science and EngineeringNankai UniversityTianjin300350 China Grupo de Química Inorgánicay Materiales Moleculares Facultad de IngenieriaUniversidad Autonoma de ChileEl Llano SubercaseauxSantiago2801 Chile

Main observation and conclusion Two ternary clusters,[As_(3)Nb(As_(3)Pb_(3))]^(3−)1 and[As_(3)Ta(As_(3)Pb_(3))]^(3−)2,were directly extracted from“K_(8)NbPbAs_(5)”and“K_(8)TaPbAs_(5)”intermetallic solid in the presence of ethylenediamine and 2.2.2-crypt,*** 1 and 2,comprising an electron-poor early transition metal-atom Nb or Ta coordinated to a As3 triangle and a bowl-like As_(3)Pb_(3).

关键词： Cluster compounds Aromaticity Zintl anions DFT calculation Sandwich structure

Magnetic filtration of an iron oxide aerosol by means of magnetizable grates

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China Particuology 2007年第1期5卷 140-144页

作者： A. alvaro J.M. Rodríguez Paulo A. Augusto A.M. Estvez Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering University of Salamanca Plaza de los Caídos 1-5 37008 Salamanca Spain Department of Chemical Engineering Faculty of Engineering University of Porto Rua Dr. Roberto Frias 4200-465 Porto Portugal

The cleaning of gases with low concentrations of small ferromagnetic or paramagnetic particles is a difficult task for conventional filtration. A new alternative procedure, magnetic filtration, is used in this work. Iron oxide aerosol was generated by elutriation of iron oxide particles from a fluidized bed consisting of a mixture of Geldart-C iron oxide powder and large spherical Geldart-B sand particles. The aerosol was filtered by means of a magnetic filter which consisted of one, two or three iron grates staggered to each other. The experimental installation contained also an isokinetic sampling system and a Microtrac SRA 150 Particle Analyser. A theoretical expression for filtration efficiency was deduced from a previous model taking into account the different forces acting on the iron oxide particles. Experimental filtration efficiency matches quite well calculated theoretical efficiency. It was found that an increase in particle size, in thee number of grates or in the applied magnetic field produced higher filtration efficiencies up to 100% in some cases. In all filtration experiments pressure drop through the magnetic filter was very small.

关键词： Iron oxide aerosol Magnetic filtration Iron grates

Adjuvant chemotherapy in breast cancer: To use or not to use, the anthracyclines

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World Journal of Clinical Oncology 2014年第3期5卷 529-538页

作者： Jennifer A Crozier Abhisek Swaika alvaro Moreno-Aspitia Department of Hematology and Oncology Mayo Clinic JacksonvilleFL 32224 United States

Breast cancer continues to be one of the leading causes of cancer mortality in the world. The treatment generally involves multiple modalities including surgery, radiation and/or chemotherapy. Anthracyclines, one of the first chemotherapeutic agents introduced in the 1960 s, has been the backbone for the last 30 years and has been used extensively so far. However, the cardiac toxicity and the concern for secondary hematological malignancy has always been a challenge. A better understanding of the tumor biology, role of Her2 expression and the discovery of trastuzumab and other anti-Her 2 agents along with other effective novel therapeutic options, have revolutionized the treatment for breast cancer. The role of anthracyclines has come under close scrutiny, especially in the adjuvant setting for patients with early stage breast cancer and those with low or intermediate risk of disease recurrence. Recent studies have highlighted such a shift in the use of anthracyclines in both the academic and community clinical practice. However, in patients with a high risk of relapse, anthracyclines still hold promise. Ongoing clinical trials are underway to further define the role of anthracyclines in such a patient population. This review highlights the development, clinical utility, limitations and potential future use of anthracyclinesin the adjuvant setting for patients with breast cancer. We consulted Pub Med, Scopus, MEDLINE, ASCO annual symposium abstracts, and http://***/ for the purpose of this review.

关键词： Breast cancer Adjuvant Neoadjuvant Chemotherapy Anthracyclines

XDEM multi-physics and multi-scale simulation technology: Review of DEM-CFD coupling, methodology and engineering applications

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Particuology 2019年第3期17卷 176-193页

作者： Bernhard Peters Maryam Baniasadi Mehdi Baniasadi Xavier Besseron alvaro Estupinan Donoso Mohammad Mohseni Gabriele Pozzetti Universite du Luxembourg 6. rue Coudenhove-Kalergi L-1359 Luxembourg

The extended discrete element method (XDEM) multi-physics and multi-scale simulation platform is being developed at the Institute of Computational Engineering, the University of Luxembourg. The platform is an advanced multi-physics simulation technology that combines flexibility and versatility to establish the next generation of multi-physics and multi-scale simulation tools. For this purpose, the simulation framework relies on coupling various predictive tools based on an Eulerian and Lagrangian approach. The Euleria n approach represents the wide field of con tinuum models;the Lagra ngian approach is perfect for characterising discrete phases. Continuum models thus include classical simulation tools, such as computational fluid dynamics simulation and finite element analysis, while an extended configuration of the classical discrete element method addresses the discrete (e.g., particulate) phase. Apart from predicting the trajectories of in dividual particles, XDEM-suite extends the application of the XDEM to estimating the thermodynamic state of each particle using advanced and optimised algorithms. The thermodynamic state may include temperature and species distributions due to chemical reaction and external heat sources. Hence, coupling these extended features with either computational fluid dynamics simulation or finite element analysis opens a wide range of applications as diverse as pharmaceuticals, agriculture, food processing, mining, construction and agricultural machinery, metals manufacturing, energy production and systems biology.

关键词： Multi-phase modelling Coupled computational fluid dynamics-discrete element method

Corneal stem cells and tissue engineering: Current advances and future perspectives

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World Journal of Stem Cells 2015年第5期7卷 806-814页

作者： Aline Lütz de Araujo Joséalvaro Pereira Gomes Clínica Lentecor Porto Alegre-RS 90570041Brazil Department of Ophthalmology and Visual Sciences Universidade Federal de São PauloSao Paulo-SP 04023062Brazil

Major advances are currently being made in regenerative medicine for cornea. Stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there aremany challenges ahead given the singularities of each cellular layer of the cornea. This review recapitulates the current data on corneal epithelial stem cells, corneal stromal stem cells and corneal endothelial cell progenitors. Corneal limbal autografts containing epithelial stem cells have been transplanted in humans for more than 20 years with great successful rates, and researchers now focus on ex vivo cultures and other cell lineages to transplant to the ocular surface. A small population of cells in the corneal endothelium was recently reported to have self-renewal capacity, although they do not proliferate in vivo. Two main obstacles have hindered endothelial cell transplantation to date: culture protocols and cell delivery methods to the posterior cornea in vivo. Human corneal stromal stem cells have been identified shortly after the recognition of precursors of endothelial cells. Stromal stem cells may have the potential to provide a direct cell-based therapeutic approach when injected to corneal scars. Furthermore, they exhibit the ability to deposit organized connective tissue in vitro and may be useful in corneal stroma engineering in the future. Recent advances and future perspectives in the field are discussed.

关键词： Cornea Stem cells Cell-based therapy Limbal transplantation Tissue engineering Cornealendothelium

Grid-connected Converters with Virtual Electromechanical Characteristics:Experimental Verification

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CSEE Journal of Power and Energy Systems 2017年第3期3卷 286-295页

作者： Weiyi Zhang Daniel Remon Ignacio Candela alvaro Luna Pedro Rodriguez Electrical Engineering Department Technical University of CataloniaBarcelona 08222Spain Department of Engineering University Loyola Andaluc´ıaSeville 41014Spain

Grid-connected power converters,which are frequently used to link renewable generation plants with the grid,are required to provide a better functionality for large scale integration of *** are expected to be gridfriendly,or even grid-supportive,instead of simply grid-feeding or *** paper designs a synchronous power controller for grid-connected converters in detail,emulating the electromechanical characteristics of synchronous machines and improving even its actual performance,as it is based on a virtual *** on this design,the grid-interfacing units are capable of showing inertia,damping,and droop characteristics as synchronous machines and presenting thus a grid-supporting *** detailed control design and experimental validation on a 10 kW laboratory setup acts as the main contribution of this paper,compared with the existing studies on generator emulation controls.

关键词： DC-AC power conversion power generation control synchronous power controller virtual electromechanical characteristics

Multiple cells of origin in cholangiocarcinoma underlie biological,epidemiological and clinical heterogeneity

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World Journal of Gastrointestinal Oncology 2012年第5期4卷 94-102页

作者： Vincenzo Cardinale Guido Carpino Lola Reid Eugenio Gaudio Domenico alvaro Department of MedicoSurgical Sciences and Biotechnologies Polo PontinoSapienza University of Rome00137 RomeItaly Department of Health Sciences University of Rome "Foro Italico"000135 RomeItaly Department of Anatomical HistologicalForensic Medicine and Orthopedics SciencesSapienza University of Rome000137 RomeItaly Department of Cell and Molecular Physiology Biomedical EngineeringProgram in Molecular Biology and BiotechnologyUNC School of MedicineChapel HillNC 27599United States Eleonora Lorillard Spencer-Cenci Foundation 00156 RomeItaly

Recent histological and molecular characterization of cholangiocarcinoma(CCA) highlights the heterogeneity of this cancer that may emerge at different sites of the biliary tree and with different macroscopic or morphological ***,different stem cell niches have been recently described in the liver and biliarytree,suggesting this as the basis of the heterogeneity of intrahepatic(IH)-and extrahepatic(EH)-CCAs,which are two largely different tumors from both biological and epidemiological points of *** complexity of the organization of the liver stem cell compartments could underlie the CCA clinical-pathological heterogeneity and the criticisms in classifying primitive liver *** recent advances highlight a possible new classification of CCAs based on cells of origin and this responds to the need of generating homogenous diagnostic,prognostic and,hopefully,therapeutic categories of IH-and EH-CCAs.

关键词： Intrahepatic cholangiocarcinoma Extrahepatic cholangiocarcinoma Cholangiocarcinoma classification Cholangiolocarcinoma Cells of origin Cancer stem cells Peribiliary glands Biliary tree stem/progenitor cells Human hepatic stem cells Risk factors Targeted therapies

Exploratory study on bitumen content determination for foamed bitumen mixes based on porosity and indirect tensile strength

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第2期4卷 131-144页

作者： May Namutebi Bjorn Birgisson alvaro Guarin Denis Jelagin Division of Highway and Railway Engineering KTH Royal Institute of Technology Stockholm Sweden Department of Civil and Environmental Engineering Makerere University Kampala Uganda

Optimum bitumen content determination is one of the major aims for foamed bitumen mix design. However, mix design procedures for foamed bitumen mixes are still under development. In this paper a method to determine the optimum bitumen content for given foamed bitumen mix based on primary aggregate structure porosity and indirect tensile strength criterion is proposed. Using packing theory concepts, the aggregate gradation is divided into three aggregate structures which are oversize, primary and secondary struc- tures. Porosity for the primary aggregate structure is determined for given bitumen contents. A maximum value for porosity of 50% for the primary aggregate structure is used to choose initial bitumen content. Furthermore, a minimum indirect tensile strength criteria is suggested to refine this bitumen content. This method enables a bitumen content value to be chosen prior to the start of experimental work, as porosity is expressed in terms of physical parameters such as aggregate and binder specific gravity, and aggregate gradation which are known before the mix design process. The bitumen content is then later refined when the indirect tensile strength is determined in the laboratory. This method would reduce resources such as time and materials that may be required during the mix design procedure.

关键词： Foamed bitumen Bitumen content Aggregate Porosity Gradation framework Indirect tensile strength