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A review of Helicobacter pylori diagnosis, treatment, and methods to detect eradication

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World Journal of Gastroenterology 2014年第6期20卷 1438-1449页

作者： Elvira Garza-González Guillermo Ignacio perez-perez Héctor Jesús Maldonado-Garza Francisco Javier Bosques-padilla Servicio de Gastroenterología y Departamento de Patología Clínica Hospital Universitario "Dr. José Eleuterio González" Universidad Autónoma de Nuevo León Departments of Medicine and Microbiology New York University School of Medicine

Helicobacter pylori (H. pylori) affects nearly half of the world’s population and, thus, is one of the most frequent and persistent bacterial infections worldwide. H. pylori is associated with peptic ulcer disease, gastric ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Various diagnostic methods exist to detect infection, and the choice of one method or another depends on several factors, such as accessibility, advantages and disadvantages of each method, cost, and the age of patients. Once H. pylori infection is diagnosed, the clinician decides whether treatment is necessity, according to the patient’s clinical condition. Typically, eradication of H. pylori is recommended for treatment and prevention of the infection. Cure rates with the standard triple therapy are acceptable, and effective quadruple therapies, sequential therapies, and concomitant therapies have been introduced as key alternatives to treat H. pylori infection. In this work, we review the main diagnostic methods used to identify H. pylori infection and to confirm eradication of infection. In addition, key factors related to treatment are reviewed.

关键词： Diagnosis Helicobacter pylori Treatment Hybrid therapy Concomitant therapy Sequential therapy

L^1→L^q Poincare Inequalities for 0y Representation Formulas

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Acta Mathematica Sinica,English Series 2002年第1期18卷 1-20页

作者： perez Carlos Departamento dr Matematicas. Universidad Autónoma de Madrid. 28049 Madrid. Spain

Civen two doubling measures μ and v in a metric apace (S.p)of homogeneous type. let B_0 S be a given ball. It has been a well-known result bv now (see)[1 4])theat the validity of an L^1→L^1 Poincaré inequality of the following form: f_B|f-f_B|dv≤cr(B)f_Bgdμ. for all metric balls B B_0 S, implies a variant of representation formula of fractonal integral type: |f(x)-f_(B(11))|≤C integral from n=B_(11) g(y)p(x, y)/μ(B(x, p(x, y)))dμ(y)+C(r(B_0))/(μ(B_0))integral from n=B_0 g(y)dμ(y). One of the main results of this paper shows that an L^1 to L^q Poincaré inequality for some 01, i.e.. (f_B|f-f_B|~q dv)^(1/q)≤cr(B) f_B gdμ, for all metric balls B B_0. will suffice to imply the above representation formula. As an immediate corollary, we can show that the weak-type condition. sup_(λ>0)(λv({x ∈ B:|f(x)-f_B|>λ}))/v(B)≤Gr (B)f_B gdμ. also implies the same formula. Analogous theorems related to high-order Poincaréinequalities and Sobolev spaces in metric spaces are also proved.

关键词： Sobolev spaces Representation formulas High-order derivatives Vector fields Metric spaces Polynomials Doubling measures Poincare inequalities

Role of dup A in virulence of Helicobacter pylori

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World Journal of Gastroenterology 2016年第46期22卷 10118-10123页

作者： Amin Talebi Bezmin Abadi Guillermo perez-perez Department of Bacteriology Faculty of Medical Sciences Tarbiat Modares University Departments of Medicine and Microbiology New York University School of Medicine and VA Medical Center

Helicobacter pylori(H. pylori) is a gastric human pathogen associated with acute and chronic gastritis, 70% of all gastric ulcers, 85% of all duodenal ulcers, and both forms of stomach cancer, mucosal-associated lymphoid tissue(MALT) lymphoma and adenocarcinoma. Recently, attention has focused on possible relationship between presence of certain virulence factor and H. pylori-associated diseases. Some contradictory data between this bacterium and related disorders has been observed since not all the colonized individuals develop to severe disease. The reported diseases plausibility related to H. pylori specific virulence factors became an interesting story about this organism. Although a number of putative virulence factors have been identified including cytotoxin-associated gene a(cag A) and vac A, there are conflicting data about their actual participation as specific risk factor for H. pylori-related diseases. Duodenal ulcer promoting gene a(dup A) is a virulence factor of H. pylori that is highly associated with duodenal ulcer development and reduced risk of gastric cancer. The prevalence of dup A in H. pylori strains isolated from western countries is relatively higher than in H. pylori strains from Asian countries. Current confusing epidemiological reports will continue unless future sophisticated and molecular studies provide data on functional and complete dup A cluster in H. pylori infected individuals. This paper elucidates available knowledge concerning role of dup A in virulence of H. pylori after a decade of its discovery.

关键词： Helicobacter pylori dup A Bacterial virulence infection Clinical outcome

mRNA levels of TLR4 and TLR5 are independent of H pylori

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World Journal of Gastroenterology 2008年第34期14卷 5306-5310页

作者： Elvira Garza-González Virgilio Bocanegra-García Francisco Javier Bosques-padilla Juan Pablo Flores-Gutiérrez Francisco Moreno Guillermo Ignacio perez-perez Departmento de Microbiología Facultad de MedicinaUniversidad Autónoma de Nuevo León Departmento de Biología Molecular y Bioingeniería UAM Reynosa Aztlán Universidad Autónoma de Tamaulipas Hospital Universitario "Dr. José Eleuterio González" Universidad Autónoma de Nuevo León Department of Medicine and Microbiology New York University School of Medicine

AIM:To determine if the presence H pylori or its viru- lence affect toll-like receptor 4 (TLR4) and TLR5 mRNA expression levels. METHODS:For the in vivo assays, gastric biopsies were obtained from 40 patients and H pylori status was determined. For the in vitro assays, human gastric adenocarcinoma mucosal cells (AGS) were cultured in the presence or absence of twelve selected H pylori strains. H pylori strains isolated from culture-positive patients and selected strains were genotyped for cagA and vacA. The cDNA was obtained from mRNA extracted from biopsies and from infected AGS cells. TLR4 and TLR5 mRNA levels were examined by real-time PCR. RESULTS: The presence of H pylori did not affect the mRNA levels of TLR4 or TLR5 in gastric biopsies. The mRNA levels of both receptors were not influenced by the vacA status (P > 0.05 for both receptors) andthere were no differences in TLR4 or TLR5 mRNA levels among the different clinical presentations/histological fi ndings (P > 0.05). In the in vitro assay, the mRNA levels of TLR4 or TLR5 in AGS cells were not influenced by the vacAs1 status or the clinical condition as-sociated with the strains (P > 0.05 for both TLR4 and TLR5). CONCLUSION: The results of this study show that the mRNA levels of TLR4 and TLR5 in gastric cells, both in vivo and in vitro, are independent of H pylori colonization and suggest that vacA may not be a significant player in the first step of innate immune recognition mediated by TLR4 or TLR5.

关键词： H pylori Toll-like receptor 4 Toll-likereceptor 5 AGS cells mRNA

The Finite-dimensional Decomposition Property in Non-Archimedean Banach Spaces

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1833-1845页

作者： Albert KUBZDELA Cristina perez-GARCIA Institute of Civil Engineering Poznań University of TechnologyUl.Piotrowo 561-138 PoznańPoland Department of Mathematics Facultad de CienciasUniversidad de CantabriaAvda.de los Castros s/n39071SantanderSpain

A non-Archimedean Banach space has the orthogonal finite-dimensional decomposition property（OFDDP） if it is the orthogonal direct sum of a sequence of finite-dimensional *** property has an influence in the non-Archimedean Grothendieck＇s approximation theory,where an open problem is the following： Let E be a non-Archimedean Banach space of countable type with the OFDDP and let D be a closed subspace of *** D have the OFDDP？ In this paper we give a negative answer to this question; we construct a Banach space of countable type with the OFDDP having a one-codimensional subspace without the *** we prove that,however,for certain classes of Banach spaces of countable type,the OFDDP is preserved by taking finite-codimensional subspaces.

关键词： Non-Archimedean Banach spaces finite-dimensional decomposition property orthogonal base

Implementing a vector surveillanceresponse system for chagas disease control:a 4-year field trial in Nicaragua

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Infectious Diseases of Poverty 2017年第1期6卷 154-165页

作者： Kota yoshioka Doribel Tercero Byron perez Jiro Nakamura Lenin perez Doctor of Public Health Program Harvard T.H.Chan School of Public HealthBostonUSA School of Tropical Medicine and Global Health Nagasaki UniversityNagasakiJapan Former Chagas Disease Control Project Japan International Cooperation AgencyManaguaNicaragua Department of Disease Prevention Ministry of Health in NicaraguaManaguaNicaragua

Background:Chagas disease is one of the neglected tropical diseases(NTDs).International goals for its control involve elimination of vector-borne *** American countries face challenges in establishing sustainable vector control programmes,since the main vector,Triatoma dimidiata,cannot be *** 2012,the Ministry of Health in Nicaragua started a field test of a vector surveillance-response system to control domestic vector *** paper reports the main findings from this pilot ***:This study was carried out from 2012 to 2015 in the Municipality of *** Japan International Cooperation Agency provided technical cooperation in designing and monitoring the surveillance-response system until *** system involved 1)vector reports by householders to health facilities,2)data analysis and planning of responses at the municipal health centre and 3)house visits or insecticide spraying by health personnel as a *** registered all vector reports and responses in a digital *** collected data were used to describe and analyse the system performance in terms of amount of vector reports as well as rates and timeliness of ***:During the study period,*** was reported 396 *** analysis identified some high-risk *** houses reported to be infested were visited by health personnel in 2013 and this response rate dropped to 39%in *** of insecticide spraying rose above 80%in 2013 but no spraying was carried out in the following 2 *** timeliness of house visits improved significantly after the responsibility was transferred from a vector control technician to primary health care ***:We argue that the proposed vector surveillance-response system is workable within the resourceconstrained health system in *** to the primary health care services was a key to improve the system *** efforts are necessary to keep adap

关键词： Chagas disease Triatoma dimidiata Vector control Surveillance-response system Programme integration Nicaragua

In vitro germination and shoot proliferation of the threatened species Cinchona officinalis L(Rubiaceae).

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Journal of Forestry Research 2016年第6期27卷 1229-1236页

作者： Rosa Armijos-Gonzalez Cesar perez-Ruiz Departamento de Ciencias Naturales Universidad Tecnica Particular de LojaCP 1101 608 LojaEcuador Departamento de Biotecnologia y Biologia Vegetal E.T.S.Ingenieros AgronomosUniversidad Politecnica de MadridCP 728040 MadridSpain

Cinchona officinalis （Rubiaceae） is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosystem, C. officinalis populations are threatened. Currently, natural regeneration of the populations is low, despite its high plant regeneration and seed formation capacity. In the present study, an efficient protocol for germination, shoot proliferation and plantlets regeneration was developed for this species. Phenolic content and germination rate of C. officinalis seeds were compared with a control species, C. pubescens. Nodal segments from seedlings of C. officinalis were cultured on Gamborg medium supplemented with different combinations of plant growth regulators. Because the phenol content is high in C. officinalis, the phenolic should be removed with hydrogen peroxide or water washes to stimulate germination. Shoots and callus developed from nodal segments within 45 days using most of the tested combinations of plant growth regulators. The best rates of shoot proliferation, callus formation and adventitious buds were obtained in medium supplemented with 5.0 mg L^-1 6-benzyl-aminopurine and 3.0 mg L^-1 indole- 3-butyfic acid.

关键词： Callus Cinchona officinalis Germination Phenols Rubiaceae Shoot

Effect of grain recrystallization on stir zone and mechanical property behavior of TRIP 780 steel

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Journal of Iron and Steel Research International 2020年第2期27卷 188-196页

作者： Gladys perez-Medina Hugo Lopez Argelia Miranda-perez Eduardo Hurtado-Delgado Postgraduate Studies Mexican Corporation in Materials ResearchSaltillo Coahuila 25290Mexico Materials Department University of Wisconsin-MilwaukeeMilwaukeeWI 53201USA

Electron backscatter diffraction(EBSD)and transmission electron microscopy were used to determine the presence of retained austenite and displacive-type phase transformation in the stir zone of friction stir welding(FSW).Severe plastic deformations occurred in the stir zone where there was an increase in the temperature attributed to the FSW process and subsequently a grain *** the recrystallization phenomena,the formation of grain evolution development in steels was resolved using *** addition,a tensile test was carried out in order to reveal the results of mechanical *** was found that the fracture zone occurred in the stir zone with an ultimate tensile strength of 587 MPa,a decrease of 267 MPa compared with that of the base *** this result,it is evident that the fracture exhibits numerous elongated dimples,distributed homogeneously,and certain locations contain cleavage fractures due to differences in the microstructure of the base *** profile tests of the welding regions were conducted,and the results showed that the stir zone was present with elevated hardness(near 350 HV).Characterization techniques revealed that the austenite-to-martensite transformation occurred in the stir zone,resulting in a loss of mechanical properties in the joint.

关键词： Friction welding Transformation-induced plasticity steel Stir zone Mechanical property Tensile test

Synthesis of hydroxymethylfurfural and furfural from hardwood and softwood pulp using ferric sulphate as catalyst

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Frontiers of Chemical Science and Engineering 2019年第3期13卷 531-542页

作者： Agneev Mukherjee Guillermo Portillo-perez Marie-Josee Dumont Bioresource Engineering Department McGill UniversityQC H9X 3V9Canada

Hydroxymethylfurfural (HMF) and furfural are promising chemicals for the creation of a bio-based economy. The development of an inexpensive catalytic system for converting cellulosic biomass into these chemicals is an important step in this regard. Ferric sulphate is a common, cheap and non-toxic Lewis acid that has been used to catalyse reactions such as wood depolymerisation. In this work, ferric sulphate was used to help the production of HMF and furfural from hardwood and softwood pulps. It was found that for hardwood pulp, the use of ferric sulphate alone gave a maximum HMF yield of 31.6 mol-%. The addition of the ionic liquid [BMIM]Cl or HCl as co-catalysts did not lead to an increase in the yields obtained. A prior decationisation step, however, resulted in HMF yields of 50.4 mol-%. Softwood pulp was harder to depolymerise than hardwood, with a yield of 28.7% obtained using ferric sulphate alone. The maximum HMF yield from softwood, 37.9 mol-%, was obtained using a combination of ferric sulphate and dilute HCl. It was thus concluded that ferric sulphate is a promising catalyst for HMF synthesis from cellulosic biomass.

关键词： 5-hydroxymethylftirfural hardwood softwood ferric sulphate biorefinery