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Journal of Rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya J.M.del Río A.de J.Morales-Ramirez M.Corea Escuela Superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.Lindavista Escuela Superior de Ingenieria Química e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.Lindavista Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/n

Polymeric nanoparticles of poly(methyl methacrylate) were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-IR) and ultraviolet-visible(UV-Vis) *** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEM).The polymeric materials were used for recovery of [Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85% of [Eu] at pH of *** images of SEM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50% of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of6.

关键词： Chelating effect Emulsion polymerization Extraction process Rare earths Stripping process [Eu]recovery

Unusual presentation of multiorgan extrapulmonary sarcoidosis

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Rheumatology & Autoimmunity 2024年第1期4卷 62-64页

作者： Ana Lilia Peralta Amaro Tania Stefanía Cabrera Castillo María de losÁngeles Macias Clavijo Fernando Méndez Gallegos Abihai Lucas Hernández Internal Medicine department Hospital de Especialidades“Dr.Antonio Fraga Mouret”Centro Médico Nacional La RazaInstituto Mexicano del Seguro SocialCiudad de MéxicoMéxico departamento de Estudios de posgrado Universidad Nacional Autónoma de México(UNAM)Ciudad de MéxicoMéxico Pathological Anatomy department Hospital de Especialidades“Dr.Antonio Fraga Mouret”Centro Médico Nacional La RazaInstituto Mexicano del Seguro SocialCiudad de MéxicoMéxico

To the Editor,Sarcoidosis is a disease known for over a century and remains enigmatic in etiology and pathophysiology.1 While the pulmonary manifestation prevails in more than 90%of cases,sarcoidosis can affect any ***,it targets the eyes,skin,lymph nodes,and,in rare instances,the liver and spleen.2 The development of the disease is significantly influenced by genetic and environmental factors,as well as gene variations on chromosome ***,first-degree relatives of patients have a heightened risk factor of *** adverse prognostic factors involve being of Black race,female gender,and having a lower *** increased incidence of sarcoidosis among firefighters who responded to the 9/11 disaster highlighted environmental triggers,including agricultural employment,metalworking,firefighting,exposure to inorganic and silica dust,and handling building supplies.1 Clinical symptoms can vary widely depending on the affected *** often relies on characteristic chest radiography findings,but approximately 10%of patients show noncaseating granulomas on biopsy without pulmonary abnormalities.2 Herein,we present a unique case of multiorgan sarcoidosis,where the sole manifestations were severe thrombocytopenia,weight loss,and a history of cerebral vascular events.

关键词： sarcoidosis spleen disaster

The movement of ＂false antennae＂ in butterflies with ＂false head＂ wing patterns

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Current Zoology 2015年第4期61卷 758-764页

作者： Tania G. LOPEZ-PALAFOX Armando LUIS-MARTINEZ Carlos CORdeRO posgrado en Ciencias Biologicas Instituto de Ecologia Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico Museo de Zoologia Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autonoma de Mexico Distrito Federal 04510 Mexico departamento de Ecologia Evolutiva Instituto de Ecologia Universidad Nacional Autonoma de M6xico Distrito Federal 04510 Mexico

In many butterfly species of the family Lycaenidae, the morphology and color pattern of the hind wings, together with certain behaviors, suggests the presence of a false head （FH） at the posterior end of the perching individual. This FH is consi- dered an adaptation to escape from visually oriented predators. A frequent component of the FH are the tails that presumably resemble the antennae, and the typical hind wings back-and-forth movement along the sagittal plane （HWM） performed while perching apparently move the tails in a way that mimics antennal movement. By exposing 33 individuals from 18 species of Lycaenidae to a stuffed insectivorous bird, we tested two alternative hypotheses regarding HWM. The first hypothesis proposes that, when the butterfly is observed at close range, the HWM distorts the shape of the false head thus reducing its deceiving effect and, therefore, selection will favor butterflies that stop moving their wings when a predator is close by; the second hypothesis says that an increase in the frequency of HWM improves its deflective effect when the butterfly confronts a predator at close range. Our results tend to support the second hypothesis because half of the butterflies started to move their hind wings or increased the rate of HWM when exposed to the stuffed bird; however a substantial proportion of butterflies （30%） stopped moving their hind wings or decreased the rate of HWM as expected from the first hypothesis. Our observations also showed that there is great variation in the rates of HWM, and demonstrated the existence of alternative ways of producing ＂vivid＂ movement of the hind wing tails （the ＂false antennae＂） in the absence of HWM [Current Zoology 61 （4）： 758-764, 2015].

关键词： Butterflies Lycaenidae Predator deception Anti-predator behavior Wing morphology

Synthesis and characterization of nano-hydroxyapatite added with magnesium obtained by wet chemical precipitation

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Progress in Natural Science:Materials International 2021年第4期31卷 575-582页

作者： Brandon A.Correa-Pi?a Omar M.Gomez-Vazquez Sandra M.Londo?o-Restrepo Luis F.Zubieta-Otero Beatriz M.Millan-Malo Mario E.Rodriguez-García posgrado en Ciencia e Ingeniería de Materiales Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla departamento de Nanotecnología Centro de Física Aplicada y Tecnología Avanzada Universidad Nacional Autónoma de México Campus Juriquilla

Biogenic hydroxyapatites from mammalian bones naturally contain traces of ions, like Mg, which play a vital role in the bone remodeling process. In this way, synthetic hydroxyapatites should include this kind of mineral. In this work, hydroxyapatite added with Mg was synthesized by wet precipitation using（NH;）H;PO;, Ca（NO;）;.4 H;O,and Mg（NO;）;.6 H;O（0, 0.032, 0.061, and 0.123 M）. Inductively coupled plasma and X-ray diffraction evidenced the Mg inclusion in the hydroxyapatite lattice in the same levels reported for natural hydroxyapatites. The calcination at 600℃ was performed to remove the reaction by-products, but it also gave rise to physicochemical changes as the coalescence and crystals recrystallization. It produced, in turn, an improvement in the crystalline quality, according to Raman analysis. despite those physicochemical changes, all the samples remained nanometric according to scanning electron microscopy imaging.

关键词： Magnesium Physicochemical properties Calcination Nanometric crystal size Coalescence Recrystallization

Socio-spatial organization reveals paternity and low kinship in the Honduran white bat(Ectophylla alba)in Costa Rica

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Integrative Zoology 2021年第5期16卷 646-658页

作者： Edgar G.GUTIÉRREZ Isabela VIVAS-TORO Daniela CARMONA-RUÍZ David VILLALOBOS-CHAVES Bernal RODRÍGUEZ-HERRERA Melina del REAL-MONROY Gloria LEÓN-AVILA Jorge ORTEGA Laboratorio de Bioconservación y Manejo Posgrado en Ciencias QuimicobiológicasDepartamento de ZoologíaEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico department of Biology University of WashingtonSeattleWashingtonUSA Escuela de Biología Universidad de Costa RicaSan JoséCosta Rica Laboratorio de Genómica Evolutiva Doctorado en Ciencias BásicasUniversidad Autónoma de ZacatecasZacatecasZac.México Laboratorio de Genética Posgrado en Ciencias QuimicobiológicasDepartamento de ZoologíaEscuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico

Ectophylla alba is a tent-making bat that roosts in mixed-sex clusters comprising adults and *** goal was to determine the genetic identity of individuals belonging to different roosting *** tested the hypothesis of kin selection as a major force structuring group *** used 9 microsatellites designed for *** to determine the genetic identity and probability of parentage of *** analyzed parentage and kinship using the software ML-Relate,GenAIEx,and *** obtained relationship probabilities(0.5)revealed a clear maternal relationship between female adults and offspring with allele compatibility,and at least 5 relationships between male adults and *** found a low degree of relatedness within roosting *** roosting groups at different sites,the mean probability of a half-sibling relationship ranged from 0.214 to 0.244 and,for full-sibling relationship,from 0.383 to ***,adult individuals were poorly related within clusters,and kinship as an evolutionary force could not explain group membership.

关键词： Ectophylla alba group composition kinship microsatellites relatedness

Cancer stem cell impact on clinical oncology

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World Journal of Stem Cells 2018年第12期10卷 183-195页

作者： Mariel E Toledo-Guzmán Gabriele D Bigoni-Ordonez Miguel Ibanez Hernandez Elizabeth Ortiz-Sánchez Subdirección de Investigación Básica Instituto Nacional de CancerologíaMexico City 14080Mexico departamento de Bioquímica Laboratorio de Terapia GénicaEscuela Nacional de Ciencias BiológicasPosgrado de Biomedicina y Biotecnología MolecularInstituto Politécnico NacionalMexico City 11340Mexico

Cancer is a widespread worldwide chronic disease. In most cases, the high mortality rate from cancer correlates with a lack of clear symptoms, which results in late diagnosis for patients, and consequently, advanced tumor disease with poor probabilities for cure, since many patients will show chemo-and radio-resistance. Several mechanisms have been studied to explain chemo-and radio-resistance to anti-tumor therapies, including cell signaling pathways, anti-apoptotic mechanisms, stemness, metabolism, and cellular phenotypes. Interestingly, the presence of cancer stem cells(CSCs), which are a subset of cells within the tumors, has been related to therapy resistance. In this review, we focus on evaluating the presence of CSCs in different tumors such as breast cancer, gastric cancer, lung cancer, and hematological neoplasias, highlighting studies where CSCs were identified in patient samples. It is evident that there has been a great drive to identify the cell surface phenotypes of CSCs so that they can be used as a tool for anti-tumor therapy treatment design. We also review the potential effect of nanoparticles, drugs, natural compounds, aldehyde dehydrogenase inhibitors, cell signaling inhibitors, and antibodies to treat CSCs from specific tumors. Taken together, we present an overview of the role of CSCs in tumorigenesis and how research is advancing to target these highly tumorigenic cells to improve oncology patient outcomes.

关键词： Cancer Targeted therapy Clinical outcome Drug resistance Cancer stem cells

Historical fluxes of metal and metalloids in an aquatic ecosystem affected by land-use change and mining activities in northwestern Mexico

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International Journal of Sediment Research 2023年第5期38卷 724-738页

作者： Ochoa-Contreras Roberto Jara-Marini Martín Enrique Ruiz-Fernández Ana Carolina Sanchez-Cabeza Joan Albert Meza-Figueroa Diana Pérez-Bernal Libia Hascibe posgrado en Ciencias Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo 2. Centro de Investigación en Alimentación y Desarrollo Unidad Hermosillo Unidad Acad emica Mazatlán Instituto de Ciencias del Mar y Limnología Universidad Nacional Autónoma de M exico departamento de Geología División de Ciencias Exactas y Naturales Universidad de Sonora Rosales y Encinas

Freshwater reservoirs are essential owing because of their ecological, economic, and social *** are particularly vulnerable to contamination, as of metal and metalloids, derived from anthropogenic activities like mining. The temporal variations in trace element concentrations(arsenic(As),mercury(Hg), chromium(Cr), copper(Cu), nickel(Ni), lead(Pb), and zinc(Zn)), enrichment, fluxes, and possible sources were evaluated by studying two sediment cores from the La Angostura(ANG) Reservoir(northwest Mexico), using210Pb geochronology. The enrichment factors showed from null to minor enrichment for most elements, but moderate to severe enrichment of mercury(Hg). Most trace element concentrations had a detrital origin, and notable Hg concentration increases since the past decade were associated with severe drought periods, likely resulting from wildfires. The observed sediment concentrations of As and Hg can cause adverse effects on biota in the ecosystem since they are above the probable effect level(PEL). development of strategies for metal attenuation in this reservoir is recommended and metals should be controlled until specific ecotoxicological studies are performed.

关键词： Aquatic ecosystems ~(210)Pb geochronology Mining activities Metals Metalloids Enrichment factors

Changes in niche differentiation and environmental filtering over a hydric stress gradient

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Journal of Plant Ecology 2020年第2期13卷 185-194页

作者： Alejandra Martínez-Blancas Carlos Martorell departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCoyoacán04510 Ciudad de MéxicoMexico posgrado en Ciencias Biológicas Universidad Nacional Autónoma de MéxicoAv.Ciudad Universitaria 3000C.P.04510CoyoacánCiudad de MéxicoMexico

Aims Diversity in communities is determined by species’ability to coexist with each other and to overcome environmental stress that may act as an environmental *** differentiation(ND)results in stronger intra-than interspecific competition and promotes *** stress affects interactions,the strength of ND may change along stress gradients.A greater diversity of plant growth forms has been observed in stressful habitats,such as deserts and alpine regions,suggesting greater ND when stress is *** tested the hypothesis that niche differences and environmental filters become stronger with *** In a semiarid grassland in southern Mexico,we sowed six annual species in the field along a hydric stress *** were grown alone(without interactions),with conspecific neighbors(intraspecific interactions)or with heterospecific neighbors(interspecific interactions).We analyzed how the ratio of intra-to interspecific competition changed along the gradient to assess how water availability determines the strength of *** also determined if hydric stress represented an environmental *** Findings We observed stronger intra-than interspecific competition,especially where hydric stress was ***,we found ND in at least some portion of the gradient for all but one *** species were hindered by stress,but others were favored by it perhaps because it eliminates soil *** strong ND was slightly more frequent with stress,our species sample was small and there were exceptions to the general pattern,so further research is needed to establish if this is a widespread phenomenon in nature.

关键词： hydrological niche species interactions environmental constraints species coexistence stabilizing mechanisms equalizing mechanisms

Reproductive performance of the Mesa silverside(Chirostoma jordani Woolman,1894)under natural and controlled photoperiods

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BIOCELL 2012年第3期36卷 105-111页

作者： JOSÉLUIS ARREDONDO-FIGUEROA LAURA GEORGINA NÚÑEZ-GARCÍA PALOMA ADRIANA HEREDIA-GUZMÁN JESÚS T.PONCE-PALAFOX Posta Zootécnica Departamento de ZootecniaCentro de Ciencias AgropecuariasUniversidad Autónoma de AguascalientesJesús MaríaAguascalientesMéxico Planta Experimental de Producción Acuícola Departamento de HidrobiologíaCBSUniversidad Autónoma Metropolitana IztapalapaMéxicoD.F Facultad de Estudios Superiores Iztacala Universidad Nacional Autónoma de MéxicoEstado de MéxicoMéxico Centro de Innovación y Transferencia Tecnológica CENITT Posgrado CBAPEscuela Nacional de Ingeniería PesqueraUniversidad Autónoma de NayaritTepicNayaritMéxico

Chirostoma jordani is a native annual species inhabiting lacustrine waters of the Central Mexico *** is widely distributed and is currently facing high environmental *** experi-ments were performed to study the reproductive performance of this *** of the experiments were conducted in 270-L indoor recirculation *** males and one female at the first stage of reproduction were included in each test.A photoperiod of 14 light hours and 10 dark hours was *** a fifth experiment,10 females and 15 males were kept in an outdoor 3,000-L recirculation tank under natural *** number of spawns,fertilised eggs and 30-day-old juveniles were counted and the survival rate was *** results indicated significant differences(Pder controlled photoperiod,and higher numbers of juveniles and a higher survival rate were observed under natural *** trials exhibited different patterns of egg produc-tion during the *** egg production in the natural-photoperiod trials followed a polynomial curve *** contrast,the trials under the controlled photoperiod showed an irregular pattern of increases and decreases in egg production.

关键词： breeding Atherinopsidae eggs juveniles survival rate

Chemical Structure of TiO Organometallic Particles Obtained by Plasma

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Advances in Nanoparticles 2013年第3期2卷 229-235页

作者： Ma. Guadalupe Olayo Francisco González-Salgado Guillermo J. Cruz Lidia Ma. Gómez Genoveva García-Rosales Maribel Gonzalez-Torres Osvaldo G. Lopez-Gracia departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México departamento de posgrado Instituto Tecnológico de Toluca Metepec México departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México posgrado en Ciencia de Materiales Facultad de Química Universidad Autónoma del Estado de México Toluca México departamento de Física Instituto Nacional de Investigaciones Nucleares Ocoyoacac México posgrado en Ciencias Químicas Facultad de Química Universidad Autónoma del Estado de México Toluca México departamento de posgrado Instituto Tecnológico de Toluca Metepec México

This work presents a study about the chemical structure of titanium oxide (TiO) particles synthesized by plasmas using titanium tetrapropoxide, Ti(-O-CH2-CH2-CH3)4. In plasmas, practically all chemical bonds are susceptible to participate in the reactions producing different results than those obtained by the traditional chemical routes. The particles obtained this way are semispheres and fibers grouped in random and layered structures in the 120-500 nm interval and mean diameter of 86.4 nm (fibers) and 308.6 nm (semispheres). The analysis of the resulting TiO structure was performed by IR and XPS finding that the main chemical state of Ti in these conditions was O2-Ti-O2 (Ti surrounded by O) which is part of the precursor structure, however, in O, the main chemical state was Ti-O-Ti formed with the rupture of the pre- cursor Ti-O-C bonds. These last bonds reduce the conjugation between the structure of both elements, O2-Ti-O2 and Ti-O-Ti, to produce organometallic compounds. Other chemical states appeared showing consecutive dehydrogenation steps during the synthesis with the formation of multiple bonds as a consequence of the continuous collisions in the plasma. These results allow us to follow the chemical reactions promoted by this kind of plasmas to produce TiO nanoparticles which are essentially conformed of intensive dehydrogenation.

关键词： TiO Particles Plasma degradation XPS TTP