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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

Patellar reconstruction in primary total knee arthroplasty using bone chips from routine cuts:A case report and review of literature

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World Journal of Methodology 2024年第2期14卷 158-166页

作者： Juan ignacio perez-Abdala Franco L De Cicco Tomas Nicolino Juan Astoul Institute of Orthopaedics“Carlos E.Ottolenghi” Italian Hospital of Buenos AiresCapital Federal 1198Argentina

BACKGROUND Total patellectomy is currently reserved for exceptional cases,such as recalcitrant patellofemoral instability and comminuted fractures,due to its demonstrated negative impact on knee ***,managing patellectomy is crucial to mitigate its inherent deleterious *** techniques have been described,including autologous or allogeneic bone grafts for reconstruction and soft tissue realignment to enhance the extensor *** SUMMARY A 73-year-old male underwent a patellectomy due to a comminuted fracture,subsequently developing osteoarthritis and experiencing a decline in functional *** with total knee replacement,we conducted a patellar reconstruction,incorporating routine bone cuts and utilizing bone chips to fashion a new *** intervention resulted in the restoration of full extension and improvement of knee *** Patellar reconstruction demonstrates benefits on knee mechanics and stabilization,contributing to enhanced outcomes and satisfaction following knee *** present an affordable technique for managing patellectomized patients undergoing total knee replacement.

关键词： Patellectomy Patella Reconstruction Knee arthroplasty Autologous bone Knee osteoarthritis Case report

Precision silviculture:use of UAVs and comparison of deep learning models for the identification and segmentation of tree crowns in pine crops

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International Journal of Digital Earth 2022年第1期15卷 2223-2238页

作者： Manuel ignacio perez Bruno Karelovic Roberto Molina Rodrigo Saavedra Pierluigi Cerulo guillermo Cabrera Department of Computer Sciences Universidad de Concepcion Biblioteca CentralConcepcionChile Celulosa Arauco y Constitucion SA I&DSantiagoChile

The monitoring of trees is crucial for the management of large areas of forest cultivations,but this process may be ***,remotely sensed data offers a solution to automate this *** this work,we used two neural network methods named You Only Look Once(YOLO)and Mask R-CNN to overcome the challenging tasks of counting,detecting,and segmenting high dimensional Red–Green–Blue(RGB)images taken from unmanned aerial vehicles(UAVs).We present a processing framework,which is suitable to generate accurate predictions for the aforementioned tasks using a reasonable amount of labeled *** compared our method using forest stands of different ages and *** counting,YOLO overestimates 8.5%of the detected trees on average,whereas Mask R-CNN overestimates a 4.7%of the *** the detection task,YOLO obtains a precision of 0.72 and a recall of 0.68 on average,while Mask R-CNN obtains a precision of 0.82 and a recall of *** segmentation,YOLO overestimates a 13.5%of the predicted area on average,whereas Mask R-CNN overestimates a 9.2%.The proposed methods present a cost-effective solution for forest monitoring using RGB images and have been successfully used to monitor∼146,500 acres of pine cultivations.

关键词： Artificial intelligence tree identification forestry remote sensing

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

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

Memory for location and visual cues in white-eared hummingbirds Hylocharis leucotis

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Current Zoology 2011年第4期57卷 468-476页

作者： guillermo perez Carlos LARA Jose VICCON-PALE Martha SIGNORET-POILLON Doctorado en Ciencias Biologicas Universidad Autonoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 Moxico D.F. Moxico Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtoncatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Moxico. Departamento el Hombre y su Ambiente. Universidad Autdnoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 MExico D.F. Mexico

In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 （4）： 468-476, 2011].

关键词： Visual cues Location White-eared hummingbird Foraging

Description of a Propulsion Unit Used in Guiding a Walking Machine by Recognizing a Three-point Bordered Path

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Chinese Journal of Mechanical Engineering 2016年第6期29卷 1157-1166页

作者： NUNEZ-ALTAMIRANO Diego A JUAREZ-CAMPOS ignacio MARQUEZ-perez Lucia FLORES-DIAZ Ociel School of Mechanical Engineering Universidad Michoacana de San Nicolas de Hidalgo Morelia Michoacan Mexico

A reconfigurable propulsion unit based on the Peaucellier-Lipkin mechanism has the ability to describe exact straight or curved paths depending on the selected ratio between the lengths of two of its links. The Peaucellier-Lipkin mechanism with one degree of freedom is transformed into a more sophisticated parallel kinematic chain by including four more degrees of freedom. The resulting propulsion unit is able to adapt its kinematic structure and reach instant centers of rotation, in accordance with the presence of three points that border a geometric path. A laser sensor mounted on the body of the machine detects each point. Once the machine has detected the exact location of the border of the road, it walks along a curve parallel to that border. Although the proposed research describes only one propulsion unit or leg, the methodology can be applied to all the legs of the walking machine. The novel 5-DOF leg is able to reach different centers of rotation, providing either the concave or convex arcs that satisfy the basic principle of displacement of walking machines.

关键词： Propulsion unit Peaucellier-Lipkin walking machine straight line mechanism.

Soil organic carbon stocks in native forest of Argentina:a useful surrogate for mitigation and conservation planning under climate variability

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Ecological Processes 2024年第1期13卷 3-24页

作者： Pablo L.Peri Juan Gaitán Matías Mastrangelo Marcelo Nosetto Pablo E.Villagra Ezequiel Balducci Martín Pinazo Roxana P.Eclesia Alejandra Von Wallis Sebastián Villarino Francisco Alaggia Marina González Polo Silvina Manrique Pablo A.Meglioli Julián Rodríguez-Souilla Martín Mónaco Jimena E.Chaves Ariel Medina ignacio Gasparri Eugenio Alvarez Arnesi María Paula Barral Axel von Müller Norberto M.Pahr Josefina Uribe Echevarria Pedro Fernández Marina Morsucci Dardo López Juan Manuel Cellini Leandro Alvarez ignacio Barberis Hernán Colomb Ludmila La Manna Sebastián Barbaro Cecilia Blundo Ximena Sirimarco Laura Cavallero Gualberto Zalazar guillermo Martínez Pastur Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Luján Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) CCT San Luis Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IANIGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Universidad Nacional de Cuyo Instituto de Investigaciones en Biodiversidad y Medioambiente (INIBIOMA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto de Investigaciones en Energía No Convencional CCT Salta-JujuyConsejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Dirección Nacional de Bosques Ministerio de Ambiente y Desarrollo Sostenible de la Nación Instituto de Ecología Regional Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )Universidad Nacional de Tucumán Universidad Nacional de Rosario Instituto de Investigaciones en Ciencias Agrarias de Rosario Centro Científico Tecnológico CONICET Grupo de Estudio de Agroecosistemas y Paisajes Rurales (GEAP) Universidad Nacional de Mar del Plata Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de La Plata (UNLP) Administración de Parques Nacionales (APN) Parque Nacional Los Alerces Centro de Estudios Ambientales Integrados (CEAI) Universidad Nacional de la Patagonia San Juan Bosco (UNPASJB) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background The nationally determined contribution（NDC） presented by Argentina within the framework of the Paris Agreement is aligned with the decisions made in the context of the United Nations Framework Conven-tion on Climate Change（UNFCCC） on the reduction of emissions derived from deforestation and forest degradation, as well as forest carbon conservation（REDD+）. In addition, climate change constitutes one of the greatest threats to forest biodiversity and ecosystem services. However, the soil organic carbon（SOC） stocks of native forests have not been incorporated into the Forest Reference Emission Levels calculations and for conservation planning under cli-mate variability due to a lack of information. The objectives of this study were:（i） to model SOC stocks to 30 cm of native forests at a national scale using climatic, topographic and vegetation as predictor variables, and（ii） to relate SOC stocks with spatial–temporal remotely sensed indices to determine biodiversity conservation concerns due to threats from high inter-annual climate *** We used 1040 forest soil samples（0–30 cm） to generate spatially explicit estimates of SOC native forests in Argentina at a spatial resolution of approximately 200 m. We selected 52 potential predictive environmental covari-ates, which represent key factors for the spatial distribution of SOC. All covariate maps were uploaded to the Google Earth Engine cloud-based computing platform for subsequent modelling. To determine the biodiversity threats from high inter-annual climate variability, we employed the spatial–temporal satellite-derived indices based on Enhanced Vegetation Index（EVI） and land surface temperature（LST） images from Landsat *** SOC model（0–30 cm depth） prediction accounted for 69% of the variation of this soil property across the whole native forest coverage in Argentina. Total mean SOC stock reached 2.81 Pg C（2.71–2.84 Pg C with a probability of 90%） for a total area of 460,790 km2,

关键词： Soil organic carbon Biodiversity Native forest Climate change mitigation Modelling Resilience

Immunotherapy and immunoescape in colorectal cancer

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World Journal of Gastroenterology 2007年第44期13卷 5822-5831页

作者： guillermo Mazzolini Oihana Murillo Catalina Atorrasagasti Juan Dubrot Iigo Tirapu Miguel Rizzo Ainhoa Arina Carlos Alfaro Arantza Azpilicueta Carmen Berasain José L perez-Gracia Alvaro Gonzalez ignacio Melero Liver Unit Facultad de Ciencias Biomédicas Universidad Austral Presidente Perón 1500 (1635) Derqui-Pilar Buenos Aires Argentina Centro de Investigación Médica Aplicada and Clínica Universitaria Universidad de Navarra Pamplona Spain

Immunotherapy encompasses a variety of interventions and techniques with the common goal of eliciting tumor cell destructive immune responses. Colorectal carcinoma often presents as metastatic disease that impedes curative surgery. Novel strategies such as active immunization with dendritic cells (DCs), gene transfer of cytokines into tumor cells or administration of immunostimulatory monoclonal antibodies (such as anti-CD137 or anti-CTLA-4) have been assessed in preclinical studies and are at an early clinical development stage. Importantly, there is accumulating evidence that chemotherapy and immunotherapy can be combined in the treatment of some cases with colorectal cancer, with synergistic potentiation as a result of antigens cross-presented by dendritic cells and/or elimination of competitor or suppressive T lymphocyte populations (regulatory T-cells). However, genetic and epigenetic unstable carcinoma cells frequently evolve mechanisms of immunoevasion that are the result of either loss of antigen presentation, or an active expression of immunosuppressive substances. Some of these actively immunosuppressive mechanisms are inducible by cytokines that signify the arrival of an effector immune response. For example, induction of 2, 3 indoleamine dioxygenase (IDO) by IFNγ in colorectal carcinoma cells. Combinational and balanced strategies fostering antigen presentation, T-cell costimulation and interference with immune regulatory mechanisms will probably take the stage in translational research in the treatment of colorectal carcinoma.

关键词： Colorectal carcinoma Immunotherapy Gene therapy interleukin-12 Dendritic cells CD137 indoleamine 2, 3 dioxygenase