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Conservation laws for energy and momentum in curved spaces

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 665-668页

作者： lópez-BONIllA J. morales J. OVANDO G. Section of Postgraduate Studies and Research Superior School of Mechanical and Electrical EngineeringNational Polytechnic InstituteCP 07738Mexico Division of Basic Sciences and Engineering Autonomous Metropolitan UniversityCP 02200Mexico

In arbitrary Riemannian 4-spaces, continuity equations are constructed which could be interpreted as conservation laws for the energy and momentum of the gravitational field. Special attention is given to general relativity to obtain, of natural manner, the pseudotensors of Einstein, landau-lifshitz, Moeller, Goldberg and Stachel, and also the conservation equations of Komar, Trautman, DuPlessis and Moss.

关键词： Noether theorem lagrangians in curved spaces Energy and momentum in Riemannian spaces Rund-lovelock identities

Cytotoxic effect of Spirulina platensis extracts on human acute leukemia Kasumi-1 and chronic myelogenous leukemia K-562 cell lines

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Asian Pacific Journal of Tropical Biomedicine 2017年第1期7卷 14-19页

作者： Flor Yohana Flores Hernandez Sanghamitra Khandual Inocencia guadalupe Ramírez lópez Center for Investigation and Assistance in Technology Design for State of JaliscoC.P.45019ZapopanJaliscoMexico

Objective: To evaluate the cytotoxic effects of Spirulina platensis extracts on acute leukemia Kasumi-1 and chronic leukemia K-562 cancer cell ***: Various concentrations of Spirulina platensis extracts(0.25–50.00 mg/m l)obtained with different solvents were used to treat cell lines for 72 h. For cytotoxic effect studies, cell viability test with trypan blue solution, MTT assay and microscopic cytomorphological assessment were ***: Spirulina extract obtained with 70% ethanol showed significant cytotoxicity in K562 and Kasumi-1 cell lines. With trypan blue solution, IC_(50) values were found to be4.64 mg/m l for K-562 and 3.68 mg/m l for Kusumi-1 cell lines. Spirulina aqueous extract also showed cytotoxicity with trypan blue method, at a slightly higher dose; where IC_(50) values were 12.68 mg/m l for K-562 and 2.13 mg/m l for Kusumi-1 cell lines. The IC_(50) values were found 0.40 mg/m l for K-562 and 0.31 mg/m l for Kusumi-1 cell lines for the 70% ethanol extract according to the MTT assay. Spirulina extract obtained with water also showed cytotoxicity but the dose was a little higher where IC_(50) values were15.77 mg/m l for K-562 and 9.44 mg/m l for Kusumi-1 cell lines. The effect of cytotoxicity with ethanol extract is quite comparable with that observed for cyclophosphamide, which is a chemical used as anticancer ***: The cytotoxicity exhibited by Spirulina extract to cancer cell lines might be due to the presence of phytopigments(carotenoids, chlorophyll, phycocyanin) as well as polysaccharides that were reported previously as constituents of the extract. So crude extracts of Spirulina can be used as a source to develop anticancer drugs.

关键词： leukemia Cytotoxicity Spirulina Carotenoids

liver histological changes and lipid peroxidation in the amphibian Ambystoma mexicanum induced by sediment elutriates from the lake Xochimilco

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Journal of Environmental Sciences 2016年第8期28卷 156-164页

作者： Esperanza Ortiz-Ordonez Eugenia lópez-lópez Jacinto Elías Sedeno-Díaz Esther Uría Ignacio Andrés morales María Estela Pérez Mineko Shibayama Instituto Politécnico Nacional Depto.de Formación Básica e InterdisciplinariaCICS-USTAv.de los Maestros s/n.Col.Sto Instituto Politécnico Nacional Laboratorio de Evaluación de la Salud de Ecosistemas AcuáticosENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Instituto Politécnico Nacional Coordinación Politécnica para la SustentabilidadEdificio de la Biblioteca Nacional3er PisoAv.Instituto Politécnico Nacional s/nesq.Wilfrido MassieuCol Instituto Politécnico Nacional Laboratorio de HistologíaENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Unidad de Servicio Académico Acuario BiologíaFacultad de CienciasUniversidad Autónoma de MéxicoCiudad Universitaria laboratorio de Infectómica Centro de Investigación y de Estudios Avanzados del IPNAv.Instituto Politécnico Nacional

lacustrine sediments accumulate pollutants that input from the lake watershed and can be released to the water column by sediment resuspension; thus, pollutants can change their bioavailability and exert adverse effects to aquatic biota. Shallow-urban lakes are particularly susceptible to receive pollutants from urban discharges and sediment resuspension. lake Xochimilco, in Mexico City, an urban-shallow lake, faces multiple problems： urban sprawl, overexploitation of aquifers, drying of springs, discharge of wastewater from treatment plants, and sediment resuspension. The aquatic biota living in this ecosystem is continuously exposed to the release of pollutants from the sediments. We assessed the risk that pollutants released from sediments from lake Xochimilco, Touristic（TZ） and Agriculture zone（AZ）, can exert on a native amphibian species of the lake（Ambystoma mexicanum） through exposure bioassays to sediment elutriates. We evaluate alterations in the amphibian by three approaches： biochemical（level of lipid peroxidation,lPO）, cellular（ultrastructure） and the liver histology of A. mexicanum and we compare them with a batch control. Additionally, we assessed heavy metals（Pb, Cd and Hg） in *** from TZ showed the highest concentrations of the metals assessed. Organisms exposed to sediment elutriates from either study sites showed higher lPO values than control organisms（p 〈 0.05）. Organisms exposed to elutriates from the TZ showed the most conspicuous damages： hepatic vasodilation of sinusoids, capillaries with erythrocytes,leukocyte infiltration and cytoplasmic vacuolation in hepatocytes. The biological responses assessed reflected the risk that faces A. mexicanum when is exposed for prolonged periods to sediment resuspension in lake Xochimilco.

关键词： Elutriates Amphibian liver Histological alterations Ultrastructure Oxidative stress Metals Urban lake

Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma

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World Journal of Gastroenterology 2024年第29期30卷 3479-3487页

作者： Miriam lópez-Gómez Maria morales Rebeca Fuerte Marta Muñoz Pedro-David Delgado-lópez Jorge Francisco Gómez-Cerezo Enrique Casado Department of Medical Oncology Precision Oncology LaboratoryInfanta Sofía University HospitalSan Sebastián de los Reyes 28231MadridSpain Department of Medical Oncology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Internal Medicine Infanta Sofía University HospitalSan Sebastián de los Reyes 28703MadridSpain Department of Pathology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Neurosurgery Burgos University HospitalBurgos 09006Spain Department of Internal Medicine Infanta Sofía University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain Department of Medical Oncology Infanta Sofia University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain

BACKGROUND Helicobacter pylori(***)is a widespread microorganism related to gastric adenocarcinoma(AC).In contrast,it has been reported that an inverse association exists between *** infection and esophageal *** mechanisms underlying this supposedly protective effect remain *** To determine the prevalence of *** infection in esophageal carcinoma patients,we performed a retrospective observational study of esophageal tumors diagnosed in our *** We retrospectively reviewed the prevalence of *** infection in a cohort of patients diagnosed with esophageal *** or previous proton pump inhibitor(PPI)usage was also *** A total of 89 patients with esophageal carcinoma(69 males,77.5%),with a mean age of 66 years(range,26-93 years)were *** was the most frequent pathological variant(n=47,52.8%),followed by squamous cell carcinoma(n=37,41.6%).Fourteen ACs(29.8%)originated in the gastroesophageal junction and 33(70.2%)in the esophageal ***,54 patients(60.7%)presented at stages III and *** *** infection occurred only in 4 patients(4.5%),3 with AC(6.3%of all ACs)and 1 with squamous cell carcinoma(2.7%of all squamous cell tumors).All patients with previous *** infection had stage *** one patient had received prior *** eradication therapy,whereas 86(96.6%)had received previous or concomitant PPI *** In our cohort of patients,and after histologic evaluation of paraffin-embedded primary tumors,we found a very low prevalence of previous *** *** also reviewed the medical history of the patients,concluding that the majority had received or were on PPI *** minimal prevalence of *** infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

关键词： Helicobacter pylori Eradication Esophageal tumor Dysbiosis Proton pump inhibitors Carcinogenesis Microbiota Incidence

Arylhydrazones Derivatives Containing a Benzothiazole Moiety, Efficient ligands in the Palladium-Catalyzed Mizoroki-Heck and Suzuki-Miyaura Cross-coupling Reactions under IR Irradiation

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Chinese Journal of Chemistry 2017年第12期35卷 1881-1888页

作者： Fernando Ortega-Jiménez José Guillermo Penieres-Carrillo José guadalupe lópez-Cortés M. Carmen Ortega-Alfaro Selene lagunas-Rivera Departamento de Cieneias Qulmicas Facultad de Estudios Superiores Cuautitlān-UNAM Campo i Avenida lro. de Mayo s/n Cuautitlán Izcalli C.P. 54740 Estado de México México Instituto de Qulmiea UNAM Circuito Exterior Ciudad Universitaria Coyoacán C.P. 04360 Cuidad de México México Instituto de Ciencias Nucleares UNAM Circuito Exterior Ciudad Universitaria Coyoacán C.P. 04360 Ciudad de México México Catedrático CONA CyT-TecNM-Instituto Tecnológico de Tuxtla Gutiérrez Carretera Panamericana Km 1080 Col Juan Crispin Tuxtla Gutiérrez C.P. 29050 Chiapas México

A simple arylhydrazone containing the benzothiazole moiety which may be used as an efficient ligand in the palladium-catalyzed Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions, under infrared irradiation as an alternative source of energy, is presented. The reactions proceeded with extremely high efficiency under mild conditions and produced very good yields.

关键词： arylhydrazones palladium-catalyzed cross-coupling reaction IR-irradiation

Pathological features and diagnosis of intraductal papillary mucinous neoplasm of the pancreas

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World Journal of Gastrointestinal Oncology 2014年第9期6卷 311-324页

作者： Víctor M Castellano-Megías Carolina Ibarrola-de Andrés guadalupe lópez-Alonso Francisco Colina-Ruizdelgado Department of Pathology Hospital Universitario de Fuenlabrada Department of Pathology Hospital Universitario "12 de Octubre"

Intraductal papillary mucinous neoplasm(IPMN) of the pancreas is a noninvasive epithelial neoplasm of mucinproducing cells arising in the main duct(MD) and/or branch ducts(BD) of the *** ducts are dilated and filled with neoplastic papillae and mucus in variable *** lacks ovarian-type stroma,unlike mucinous cystic neoplasm,and is defined as a grossly visible entity(≥ 5 mm),unlike pancreatic intraepithelial *** the use of high-resolution imaging techniques,very small IPMNs are increasingly being *** IPMNs are solitary and located in the pancreatic head,although 20%-40% are *** classification in MD type,BD type and mixed or combined type reflects biological differences with important prognostic and preoperative clinical management *** on cytoarchitectural atypia,IPMN is classified into low-grade,intermediategrade and high-grade *** on histological features and mucin(MUC) immunophenotype,IPMNs are classified into gastric,intestinal,pancreatobiliary and oncocytic *** different phenotypes can be observed together,with the IPMN classified according to the predominant *** pathways have been suggested:gastric phenotype corresponds to less aggressive uncommitted cells(MUC1-,MUC2-,MUC5 AC +,MUC6 +) with the capacity to evolve to intestinal phenotype(intestinal pathway)(MUC1-,MUC2 +,MUC5 AC +,MUC6- or weak +) or pancreatobiliary /oncocytic phenotypes(pyloropancreatic pathway)(MUC1 +,MUC 2-,MUC5 AC +,MUC 6 +) becoming more *** of IPMN is excellent but critically worsens when invasive carcinoma arises(about 40% of IPMNs),except in some cases of minimal *** clinical challenge is to establish which IPMNs should be removed because of their higher risk of developing invasive *** resected,they must be extensively sampled or,much better,submitted in its entirety for microscopic study to completely rule out associated invasive carcinoma.

关键词： Mucinous pancreatic cysts Intraductal papillary mucinous neoplasm Main duct intraductal papillary mucinous neoplasm Branch duct intraductal papillary mucinous neoplasm Mucins

Bacterial extracts and bioformulates as a promising control of fruit body rot and root rot in avocado cv. Hass

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Journal of Integrative Agriculture 2020年第3期19卷 748-758页

作者： David GRANADA lorena lÓpez-lUJAN Sara RAMIREZ-RESTREPO Juan morales Carlos PElÁEZ-JARAMIllO Galdino ANDRADE Juan Carlos BEDOYA-PEREZ Phytosanitary and Biological Control Unit Corporation for Biological ResearchMedellin 050034Colombia Faculty of Health Sciences Institution University Colegio Mayor de AntioquiaMedellin 050034Colombia Department of Agronomic Sciences National University of ColombiaMedellin 050034Colombia Faculty of Exact Sciences University of AntioquiaMedellin 050010Colombia Department of Microbiology Londrina State UniversityLondrina 86051-990Brazil

At least 20-40% of annual losses of avocado crops are caused by pathogenic *** chemical treatments of these diseases are inefficient,cause environmental pollution and are increasingly restricted by international *** work aimed to assess the biocontrol capacity of a bacterial extract to protect avocado fruits and plants from pathogen *** from the bacterial isolate Serratia ***5.1 were obtained from liquid fermentations in a biorreactor.A body rot postharvest infection model with Colletotrichum gloeosporioides on fruits was ***,packaging conditions were simulated using the bacterial extract and the commercial fungicide prochloraz as a positive ***,seedlings infections with Phytophthora cinnamomi were performed on two types of avocado(West Indian race and ***).The Area Under Disease Progress Curve(AUDPC) was recorded using the bacterial extract and a commercial product with fosetyl-aluminium as *** bacterial extract significantly reduced infections by *** on injured avocado fruits at 31.1 μg ml^-*** fruits were also protected against body rot infections at the same concentration and showed no significant differences with the commercial *** the other hand,AUDPC in the seedlings was significantly reduced with the extract treatment at 3 μg ml^-1 compared to the ***,a possible phytotoxicity effect of the extract was evidenced in the seedlings and confirmed by pathogen recovery and tests on Raphanus sativus ***,formulations of the extracts(emulsion and emulsifiable concentrate) were prepared,and bioactive stability was assessed for 8 *** emulsion formulates demonstrated very stable bioactivity against *** extract and the emulsion formulate showed promising results for the control of avocado *** bioproducts based on this type of active principles could be developed for the benefit of avocado industry.

关键词： Colletotrichum gloeosporioides Phytophthora cinnamomi Serratia sp. antagonistic microbes secondary metabolites biofungicide

Spectrum of neuropsychiatric symptoms in chronic post-stroke aphasia

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World Journal of Psychiatry 2022年第3期12卷 450-469页

作者： lisa Edelkraut Diana lópez-Barroso María JoséTorres-Prioris Sergio E Starkstein Ricardo E Jorge Jessica Aloisi Marcelo l Berthier guadalupe Dávila Department of Psychobiology and Methodology of Behavioral Science Faculty of Psychology and Speech TherapyUniversity of MalagaMalaga 29071Spain Cognitive Neurology and Aphasia Unit Centro de Investigaciones Médico-SanitariasUniversity of MalagaMalaga 29010Spain Instituto de Investigación Biomédica de Málaga University of MalagaMalaga 29010Spain School of Psychiatry and Neurosciences The University of Western AustraliaPerth 6009Australia Department of Psychiatry and Behavioral Sciences Baylor College of MedicineHoustonTX 77030United States

BACKGROUND Neuropsychiatric symptoms(NPS)have been insufficiently examined in persons with aphasia(PWA)because most previous studies exclude participants with language and communication *** To report a two-part study consisting of a literature review and an observational study on NPS in post-stroke *** Study 1 reviewed articles obtained from PubMed,PsycINFO,Google Scholar and Cochrane databases after cross-referencing key words of post-stroke aphasia to NPS and *** 2 examined language deficits and activities of daily living in 20 PWA(median age:58,range:28-65 years;13 men)with the Western Aphasia Battery-Revised and the Barthel Index,*** of these 20 PWA were proxy-evaluated with the Neuropsychiatric Inventory and domain-specific scales,including the Stroke Aphasia Depression Questionnaire-10 item version and the Starkstein Apathy *** addition,an adapted version of the Hospital Anxiety and Depression Scale was directly administered to the PWA *** observational study is based on the baseline assessment of an intervention clinical trial(EudraCT:2017-002858-36;*** identifier:NCT04134416).RESUlTS The literature review revealed a broad spectrum of NPS in PWA,including depression,anxiety,apathy,agitation/aggression,eating and sleep disorders,psychosis,and hypomania/*** findings alert to the need for improving assessment and treatment approaches of NPS taking into consideration their frequent occurrence in *** 2 showed that the 20 participants had mild-to-moderate aphasia severity and were functionally independent.A wide range of comorbid NPS was found in the post-stroke aphasic population(median number of NPS:5,range:1-8).The majority of PWA(75%)had depressive symptoms,followed by agitation/aggression(70%),irritability(70%),anxiety(65%)and appetite/eating symptoms(65%).Half of them also presented symptoms of apathy,whereas euphoria and psychotic symptoms were rare(5%).Domain

关键词： Aphasia Stroke Neuropsychiatric symptoms Anxiety Apathy Depression

Ion channels in liver diseases and hepatocellular carcinoma: potential tools for diagnosis, prognosis, and therapy

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Hepatoma Research 2020年第4期6卷 1-16页

作者： María de guadalupe Chávez-lópez Andrea Cruz-Díaz Karla Nicol Tlapalcoyoa-Apanco Julio IsaelPérez-Carreón Javier Camacho Department of Pharmacology Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMexico City 07360Mexico Escuela de Ciencias de la Salud Universidad del Valle de MéxicoMexico City 04910Mexico Instituto Nacional de Medicina Genómica Mexico City 14610Mexico

Cancer is a major cause of death *** carcinoma(HCC)is one of the malignancies with the highest mortality-to-incidence ratio(>0.9),and in some countries this value is up to ***,many patients are diagnosed at advanced stages of the ***,HCC early markers,as well as novel therapeutic approaches,are urgently *** is the main type of liver cancer and it is associated with different factors including alcohol use,viral infections,and fatty liver disease.A significant percentage of HCC patients previously had liver *** ion channels have been proposed as novel potential markers and therapeutic targets for diverse cancers including ***,we review most of the findings associating ion channel expression with HCC and its etiological factors,as well as some possible pro-tumorigenic mechanisms of action for ion channels in *** therapies for HCC treatment and prevention are also *** channel targeting offers a plethora of opportunities for HCC prevention,early diagnosis,and therapy that may help to reduce the extremely high mortality-to-incidence ratio of this malignancy.

关键词： Ion channels hepatocellular carcinoma hepatitis virus cirrhosis liver disease alcohol