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Thinking outside the black box:are the brain endothelial cells the new main target in Alzheimer's disease?

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Neural Regeneration Research 2023年第12期18卷 2592-2598页

作者： Enrique Estudillo adolfo López-Ornelas Alejandro Rodríguez-Oviedo Neptali Gutiérrez de la cruz marco Antonio Vargas-Hernández Adriana Jiménez Laboratorio de Reprogramación Celular Instituto Nacional de Neurología y Neurocirugía Manuel Velasco SuárezMexico CityMexico División de Investigación Hospital Juárez de MéxicoMexico CityMexico Hospital Nacional Homeopático Hospitales Federales de ReferenciaMexico CityMexico Facultad de Ciencias Universidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de morfología Escuela Militar de Graduados de SanidadSecretaría de la Defensa NacionalBatalla de CelayaLomas de SoteloMiguel HidalgoMexico CityMexico Escuela militar de Graduados de Sanidad Secretaría de la Defensa NacionalBatalla de CelayaLomas de SoteloMiguel HidalgoMexico CityMexico

The blood-brain barrier is the interface through which the brain interacts with the milieu and consists mainly of a sophisticated network of brain endothelial cells that forms blood vessels and selectively moves molecules inside and outside the brain through multiple mechanisms of *** brain endothelial cell function is crucial for brain homeostasis,their role in neurodegenerative diseases has historically not been considered with the same importance as other brain cells such as microglia,astroglia,neurons,or even molecules such as amyloid beta,Tau,or ***'s disease is the most common neurodegenerative disease,and brain endothelial cell dysfunction has been reported by several ***,its impairment has barely been considered as a potential therapeutic *** we review the most recent advances in the relationship between Alzheimer's disease and brain endothelial cells commitment and analyze the possible mechanisms through which their alterations contribute to this neurodegenerative disease,highlighting their inflammatory phenotype and the possibility of an impaired secretory pattern of brain endothelial cells that could contribute to the progression of this ***,we discuss why shall brain endothelial cells be appreciated as a therapeutic target instead of solely an obstacle for delivering treatments to the injured brain in Alzheimer's disease.

关键词： dementia endothelial cells neurodegeneration neuroinflammation neuronal death paracellular transport transcellular transport

On a Generalized model in Accelerated Life Testing

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Open Journal of Statistics 2012年第2期2卷 184-187页

作者： Eduardo L. cruz adolfo m. De Guzman Department of Epidemiology and Biostatistics University of the Philippines Manila Philippines School of Statistics University of the Philippines Quezon City Philippines

The main objective of accelerated life tests in this setting is the recovery of the distribution of the random variable representing lifetime which is difficult to observe at a certain level of a given stress factor. A general model for accelerated life test is proposed that utilizes the inverse problem approach, that is, the variable is observe at different level/s and the transfer function is used to recover the elusive random variable (life time). The problem then is reduced to finding the transfer function. We derive some properties of the proposed general model. The Lognormal distribution and the Arrhenius model for lifetime are used as examples. Its relationship with the Cox proportional hazards model is also discussed.

关键词： Accelerated Life Test Arrhenius model Inverse Problem

BaTiO_(3)solid solutions co-doped with Gd^(3+)and Eu^(3+):Synthesis,structural evolution and dielectric properties

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Journal of Rare Earths 2024年第10期42卷 1920-1926页

作者： R.martínez-López m.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández m.Reyes-Pérez m.I.Valenzuela-Carrillo G.Urbano-Reyes V.E.Reyes-cruz G.I.Dávila-Pulido Academic Area of Earth Sciences and materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico metallurgy and materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and Eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and Eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 mPa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)Eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and Eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic Eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and Eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium Europium Synthesis Rare earths

Performance Evaluation of Wavelength Division multiplexing Photonic Analogue-to-Digital Converters for High-Resolution Radar Systems

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Optics and Photonics Journal 2019年第12期9卷 219-234页

作者： Pedro E. D. cruz Tiago m. F. Alves adolfo V. T. Cartaxo Instituto de Telecomunicações Lisboa Portugal Instituto Universitário de Lisboa (ISCTE-IUL) Lisboa Portugal

The performance of the wavelength division multiplexing (WDm) photonic analogue-to-digital converter (ADC) used for digitization of high-resolution radar systems is evaluated numerically by using the peak signal-to-noise ratio (SNR) metric. Two different WDm photonic ADC architectures are considered for the digitization of radar signals with 5 GHz of bandwidth (spatial resolution of 3 cm), in order to provide a comprehensive study of the compromises present when deploying radar signals with high-resolution: 1) a four-channel architecture with each channel employing an ADC with 5 GSamples/s, and 2) an eight-channel architecture with each channel employing an ADC with 2.5 GSamples/s. For peak powers of the pulsed source between 10 and 20 dBm and a distance between the radar antenna and the sensing object of 2.4 meters, peak SNR levels between 29 and 39 dB are achieved with the eight-channel architecture, which shows higher peak SNR levels when compared with the four-channel architecture. For the eight-channel architecture and for the same peak powers of the pulsed source, peak SNR levels between 11 and 16 dB are obtained when the distance increases to 13.5 meters. With this evaluation using the peak SNR, it is possible to assess the performance limits when choosing a specific radar range, while keeping the same resolution.

关键词： Analogue-to-Digital Converter Radar Signal-to-Noise Ratio Wavelength Division multiplexing

Solid Particle Erosion Behaviour of TiN Coating on AISI 4140 Steel

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Journal of Surface Engineered materials and Advanced Technology 2014年第1期4卷 1-8页

作者： J. R. Laguna-Camacho J. E. Escalante-martínez R. cruz-Vicencio J. V. méndez-méndez I. Arzate-Vázquez I. Hernández-Romero m. Vite-Torres Centro de Nanociencias y micro y Nanotecnologías IPN Mexico City México Faculty of Chemical Engineering Universidad Veracruzana Poza Rica de Hidalgo Veracruz México Faculty of Electric and mechanical Engineering Universidad Veracruzana Poza Rica de Hidalgo Veracruz México Instituto Politécnico Nacional SEPI ESIME Unidad Profesional “Adolfo López Mateos” Tribology Group Mechanical Engineering Department Mexico City México

In this study, the performance against erosive wear of PVD TiN (titanium nitride) coating was evaluated using an erosion test rig similar to that described in the standard ASTm G76-95. This coating normally has various industrial applications such as tapping, drilling, dry machining and punching. Angular silicon carbide (SiC) was used as an abrasive particle with a grain size of 350-450 μm. Erosion tests were carried out using different incident angles, 30°, 45°, 60° and 90° with a particle velocity of 24 ± 2 m/s, an abrasive flow rate of 0.7 ± 0.5 g/min, and the test temperature was between 35°C and 40°C. The particle velocity and the abrasive flow rate were low in all of the tests to reduce the interaction between the incident and the rebounding particles in the system. The surfaces were examined with a scanning electron microscope (SEm) to characterize the erosive damage. The wear mechanisms identified were brittle fracture characterized by radial cracks on the surface by multiple impact and a few pits at 30°, while a few cracks and the formation of craters in random positions were observed at angles near or at 90°. Elliptical scars were observed at 30° and 45°, which are a characteristic feature when the specimens are impacted at low-incident angles (α ≤ 45°) whereas a roughly circular scar was seen at 60° and 90°. In addition, roughness variations were analyzed using atomic force microscopy (AFm), before and after the erosion tests, and the results exhibited an increase in the roughness as the TiN samples were impacted at angles near or at 90°.

关键词： Erosion Wear PVD Nitride Coating TiN Wear mechanisms

Novel TINF2 gene mutation in dyskeratosis congenita with extremely short telomeres:A case report

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World Journal of Clinical Cases 2022年第33期10卷 12440-12446页

作者： Verónica Judith Picos-Cárdenas Saúl Armando Beltrán-Ontiveros JoséAlfonso cruz-Ramos JoséAlfredo Contreras-Gutiérrez Eliakym Arámbula-meraz Carla Angulo-Rojo Alma marlene Guadrón-Llanos Emir adolfo Leal-León Dora maría Cedano-Prieto Juan Pablo meza-Espinoza Laboratorio de Genética Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Centro de Investigación y Docencia en Ciencias de la Salud Hospital Civil de CuliacánUniversidad Autónoma de SinaloaCuliacán 80030SinaloaMexico Departamento de Clínicas médicas Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340JaliscoMexico Facultad de medicina Universidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Laboratorio de Genética y Biología molecular Facultad de Ciencias Químico-BiológicasUniversidad Autónoma de SinaloaCuliacán 80010SinaloaMexico Laboratorio de Neurociencias Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Laboratorio de Diabetes y Comorbilidades Facultad de MedicinaUniversidad Autónoma de SinaloaCuliacán 80018SinaloaMexico Facultad de medicina Universidad Autónoma de TamaulipasMatamoros 87349TamaulipasMexico

BACKGROUND Dyskeratosis congenita is a rare disease characterized by bone marrow failure and a clinical triad of oral leukoplakia,nail dystrophy,and abnormal skin *** genetics of dyskeratosis congenita include mutations in genes involved in telomere maintenance,including *** SUmmARY Here,we report a female patient who presented thrombocytopenia,anemia,reticulate hyperpigmentation,dystrophy in fingernails and toenails,and leukoplakia on the tongue.A histopathological study of the skin showed dyskeratocytes;however,a bone marrow biopsy revealed normal cell *** patient was diagnosed with dyskeratosis congenita,but her family history did not reveal significant ***-exome sequencing showed a novel heterozygous punctual mutation in exon 6 from the TINF2 gene,namely,Nm_001099274.1:-c.854delp.(Val285-Alafs*32).An analysis of telomere length showed short telomeres relative to the patient’s *** The disease in this patient was caused by a germline novel mutation of TINF2 in one of her parents.

关键词： Dyskeratosis congenita TINF2 Germline mutation Novel mutation Short telomeres Case report

The timing of bowel preparation before colonoscopy determines the quality of cleansing,and is a significant factor contributing to the detection of flat lesions:A randomized study

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World Journal of Gastroenterology 2006年第38期12卷 6161-6166页

作者： adolfo Parra-Blanco David Nicolás-Pérez Antonio Gimeno-García Begoa Grosso Alejandro Jiménez Juan Ortega Enrique Quintero Department of Gastroenterology Hospital Universitario de Canarias La Laguna 38109 Santa Cruz de Tenerife Spain Research Unit Hospital Universitario de Canarias La Laguna 38109 Santa Cruz de Tenerife Spain

AIm： To compare the cleansing quality of polyethylene glycol electrolyte solution and sodium phosphate with different schedules of administration, and to evaluate whether the timing of the administration of bowel preparation affects the detection of polyps. mETHODS： One hundred and seventy-seven consecutive outpatients scheduled for colonoscopy were randomized in one of four groups to receive polyethylene glycol electrolyte solution or oral sodium phosphate with two different timing schedules. Quality of cleansing, polyp detection, and tolerance were evaluated. RESULTS： Patients receiving polyethylene glycol or sodium phosphate on the same day as the colonoscopy, obtained good to excellent global cleansing scores more frequently than patients who received polyethylene glycol or sodium phosphate on the day prior to the procedure （P 〈 0.001）. Flat lesions, but not fiat adenomas, were more frequent in patients prepared on the same day （P = 0.02）. CONCLUSION： The quality of colonic cleansing and the detection of fiat lesions are significantly improved when the preparation is taken on the day of the colonoscopy.

关键词： Colonoscopy Preparation Polyp Flat lesion Sodium phosphate Polyethylene glycol

Achieving the best bowel preparation for colonoscopy

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World Journal of Gastroenterology 2014年第47期20卷 17709-17726页

作者： adolfo Parra-Blanco Alex Ruiz manuel Alvarez-Lobos Ana Amorós Juan Cristóbal Gana Patricio Ibáez Akiko Ono Takahiro Fujii Department of Gastroenterology Escuela de MedicinaPontificia Universidad Católica de ChileSantiago 833-0024Chile Department of Gastroenterology Hospital Universitario de la Candelaria38916 Santa Cruz de TenerifeSpain Gastroenterology and Nutrition Unit Division of PediatricsEscuela de MedicinaPontificia Universidad Católica de ChileSantiago 833-0024Chile Department of Gastroenterology Hospital Universitario Virgen de la Arrixaca30001 MurciaSpain TF Clinic Tokyo 197-0804Japan

Bowel preparation is a core issue in colonoscopy,as it is closely related to the quality of the *** often find that bowel preparation is the most unpleasant part of the *** is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic *** spite of its importance and potential implications,until recently,bowel preparation has not been the subject of much *** most commonly used agents are high-volume polyethylene glycol(PEG)electrolyte solution and sodium *** has been some confusion,even in published meta-analyses,regarding which of the two agents provides better *** is clear now that both PEG and sodium phosphate are effectivewhen administered with proper ***,the timing of administration is recognized as one of the central factors to the quality of *** bowel preparation agent should be administered,at least in part,a few hours in advance of the *** low volume agents are available,and either new or modified schedules with PEG that usually improve *** adjuvants can also be used to reduce the volume of PEG,or to improve the efficacy of other *** factors apart from the choice of agent can improve the quality of bowel *** instance,the effect of diet before colonoscopy has not been completely clarified,but an exclusively liquid diet is probably not required,and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the *** patients,such as diabetics and persons with heart or kidney disease,require modified procedures and certain *** preparation for pediatric patients is also reviewed *** such cases,PEG remains the most commonly used *** detecting neoplasia is not the main objective with these patients,less intensive preparation may *** considerations must be made for patients with inflammatory bowel disease,including

关键词： Colonoscopy Optimal preparation Polyethylene glycol Sodium phosphate Special patients Timing

medicinal properties of Angelica archangelica root extract: Cytotoxicity in breast cancer cells and its protective effects against in vivo tumor development

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Journal of Integrative medicine 2019年第2期17卷 132-140页

作者： Carlos R.Oliveira Daniel G.Spindola Daniel m.Garcia adolfo Erustes Alexandre Bechara Caroline Palmeira-dos-Santos Soraya S.Smaili Gustavo J.S.Pereira André Hinsberger Ezequiel P.Viriato maria Cristina marcucci Alexandra C.H.F.Sawaya Samantha L.Tomaz Elaine G.Rodrigues Claudia Bincoletto Departamento de Farmacologia Escola Paulista de Medicina (EPM) Universidade Federal de Sao Paulo (UNIFESP) Grupo de Fitocomplexos e Sinalizacao Celular Escola de Ciências da Saúde Universidade Anhembi Morumbi Faculdade de Ciências Farmacêuticas e Bioquímicas Oswaldo cruz Laboratório de Produtos Naturais e Quimiometria Programa de pós-graduacao em Farmácia e Biotecnologia Universidade Anhanguera de Sao Paulo Faculdade de Ciências Farmacêuticas Universidade Estadual de Campinas (UNICAMP) Unidade de Oncologia Experimental EPM Universidade Federal de Sao Paulo (UNIFESP)

Objective: Although Angelica archangelica is a medicinal and aromatic plant with a long history of use for both medicinal and food purposes, there are no studies regarding the antineoplastic activity of its *** study aimed to evaluate the cytotoxicity and antitumor effects of the crude extract of A. archangelica root(CEAA) on breast ***: The cytotoxicity of CEAA against breast adenocarcinoma cells(4T1 and mCF-7) was evaluated by a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide(mTT) assay. morphological and biochemical changes were detected by Hoechst 33342/propidium iodide(PI) and annexin V/PI staining. Cytosolic calcium mobilization was evaluated in cells staining with FURA-4 NW. Immunoblotting was used to determine the effect of CEAA on anti-and pro-apoptotic proteins(Bcl-2 and Bax, respectively).The 4 T1 cell-challenged mice were used for in vivo ***: Using ultra-high-performance liquid chromatography–mass spectrometry analysis, angelicin, a constituent of the roots and leaves of A. archangelica, was found to be the major constituent of the CEAA evaluated in this study(73 mg/mL). The CEAA was cytotoxic for both breast cancer cell lines studied but not for human fibroblasts. Treatment of 4 T1 cells with the CEAA increased Bax protein levels accompanied by decreased Bcl-2 expression, in the presence of cleaved caspase-3 and cytosolic calcium mobilization, suggesting mitochondrial involvement in breast cancer cell death induced by the CEAA in this cell line. No changes on the Bcl-2/Bax ratio were observed in CEAA-treated mCF7 cells. Gavage administration of the CEAA(500 mg/kg) to 4T1 cell-challenged mice significantly decreased tumor growth when compared with untreated ***: Altogether, our data show the antitumor potential of the CEAA against breast cancer cells in vitro and in vivo. Further research is necessary to better elucidate the pharmacological application of the CEAA in breast cancer therapy.

关键词： Angelica archangelica Umbelliferae Apoptosis Cell death Breast cancer Angelicin