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Vargas-Zamarripa M, Rivera AA, Sierra U, Salas P, Serafín-Muñoz AH, Ramírez-García G. Improved charge-transfer resonance in graphene oxide/ZrO 2 substrates for plasmonic-free SERS determination of methyl parathion. Chemosphere 2023; 320:138081. [PMID: 36758819 DOI: 10.1016/j.chemosphere.2023.138081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/06/2023] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
This work reports a sensitive SERS substrate based on graphene oxide (GO) and quantum-sized ZrO2 nanoparticles (GO/ZrO2) for label-free determination of the organophosphate pesticide methyl parathion (MP). The enhanced light-matter interactions and the consequent SERS effect in these substrates resulted from the effective charge transfer (CT) mechanism attributed to synergistic contributions of three main factors: i) the strong molecular adherence of the MP molecules and the ZrO2 surface which allows the first layer-effect, ii) the relatively abundant surface defects in low dimensional ZrO2 semiconductor NPs, which act as intermediate electronic states that reduce the large bandgap barrier, and iii) the hindered charge recombination derived from the transference of the photoinduced holes to the GO layer. This mechanism allowed an enhancement factor of 8.78 × 104 for GO/ZrO2-based substrates, which is more than 5-fold higher than the enhancement observed for platforms without GO. A detection limit of 0.12 μM was achieved with an outstanding repeatability (variation ≤4.5%) and a linear range up to 10 μM, which is sensitive enough to determine the maximal MP concentration permissible in drinking water according to international regulations. Furthermore, recovery rates between 97.4 and 102.1% were determined in irrigation water runoffs, strawberry and black tea extracts, demonstrating the reliability of the hybrid GO/ZrO2 substrate for the organophosphate pesticides quantification in samples related to agri-food sectors and environmental monitoring.
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Affiliation(s)
- Marlene Vargas-Zamarripa
- Biofunctional Nanomaterials Laboratory, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico; División de Ingenierías, Universidad de Guanajuato, Av. Juárez 77, C.P. 36000, Guanajuato, Mexico
| | - Aura A Rivera
- Biofunctional Nanomaterials Laboratory, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico
| | - Uriel Sierra
- Laboratorio Nacional de Materiales Grafénicos. Centro de Investigación en Química Aplicada, 140, Blvd. Enrique Reyna, Saltillo, Coahuila, 25294, Mexico
| | - Pedro Salas
- Biofunctional Nanomaterials Laboratory, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico
| | - Alma H Serafín-Muñoz
- División de Ingenierías, Universidad de Guanajuato, Av. Juárez 77, C.P. 36000, Guanajuato, Mexico
| | - Gonzalo Ramírez-García
- Biofunctional Nanomaterials Laboratory, Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico.
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Thomas CA, Naidu SP, Scheirich P, Moskovitz NA, Pravec P, Chesley SR, Rivkin AS, Osip DJ, Lister TA, Benner LAM, Brozović M, Contreras C, Morrell N, Rożek A, Kušnirák P, Hornoch K, Mages D, Taylor PA, Seymour AD, Snodgrass C, Jørgensen UG, Dominik M, Skiff B, Polakis T, Knight MM, Farnham TL, Giorgini JD, Rush B, Bellerose J, Salas P, Armentrout WP, Watts G, Busch MW, Chatelain J, Gomez E, Greenstreet S, Phillips L, Bonavita M, Burgdorf MJ, Khalouei E, Longa-Peña P, Rabus M, Sajadian S, Chabot NL, Cheng AF, Ryan WH, Ryan EV, Holt CE, Agrusa HF. Orbital period change of Dimorphos due to the DART kinetic impact. Nature 2023; 616:448-451. [PMID: 36858072 PMCID: PMC10115635 DOI: 10.1038/s41586-023-05805-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 02/07/2023] [Indexed: 03/03/2023]
Abstract
The Double Asteroid Redirection Test (DART) spacecraft successfully performed the first test of a kinetic impactor for asteroid deflection by impacting Dimorphos, the secondary of near-Earth binary asteroid (65803) Didymos, and changing the orbital period of Dimorphos. A change in orbital period of approximately 7 min was expected if the incident momentum from the DART spacecraft was directly transferred to the asteroid target in a perfectly inelastic collision1, but studies of the probable impact conditions and asteroid properties indicated that a considerable momentum enhancement (β) was possible2,3. In the years before impact, we used lightcurve observations to accurately determine the pre-impact orbit parameters of Dimorphos with respect to Didymos4-6. Here we report the change in the orbital period of Dimorphos as a result of the DART kinetic impact to be -33.0 ± 1.0 (3σ) min. Using new Earth-based lightcurve and radar observations, two independent approaches determined identical values for the change in the orbital period. This large orbit period change suggests that ejecta contributed a substantial amount of momentum to the asteroid beyond what the DART spacecraft carried.
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Affiliation(s)
| | - Shantanu P Naidu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Peter Scheirich
- Astronomical Institute of the Czech Academy of Sciences, Ondřejov, Czech Republic
| | | | - Petr Pravec
- Astronomical Institute of the Czech Academy of Sciences, Ondřejov, Czech Republic
| | - Steven R Chesley
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Andrew S Rivkin
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - David J Osip
- Carnegie Institution for Science, Las Campanas Observatory, La Serena, Chile
| | | | - Lance A M Benner
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Marina Brozović
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Carlos Contreras
- Carnegie Institution for Science, Las Campanas Observatory, La Serena, Chile
| | - Nidia Morrell
- Carnegie Institution for Science, Las Campanas Observatory, La Serena, Chile
| | - Agata Rożek
- University of Edinburgh, Royal Observatory, Edinburgh, UK
| | - Peter Kušnirák
- Astronomical Institute of the Czech Academy of Sciences, Ondřejov, Czech Republic
| | - Kamil Hornoch
- Astronomical Institute of the Czech Academy of Sciences, Ondřejov, Czech Republic
| | - Declan Mages
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | | | | | | | - Uffe G Jørgensen
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | | | - Jon D Giorgini
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Brian Rush
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | - Julie Bellerose
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
| | | | | | | | | | | | - Edward Gomez
- Las Cumbres Observatory, Goleta, CA, USA
- Cardiff University, Cardiff, UK
| | | | - Liz Phillips
- Las Cumbres Observatory, Goleta, CA, USA
- University of California, Santa Barbara, Santa Barbara, CA, USA
| | | | | | | | | | - Markus Rabus
- Universidad Católica de la Santísima Concepción, Concepción, Chile
| | | | - Nancy L Chabot
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Andrew F Cheng
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - William H Ryan
- Magdalena Ridge Observatory, New Mexico Institute of Mining and Technology, Socorro, NM, USA
| | - Eileen V Ryan
- Magdalena Ridge Observatory, New Mexico Institute of Mining and Technology, Socorro, NM, USA
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Bademci R, Temidayo Talabi MO, Salas P, Blanco MR, Riart GC, Bollo J, Raventós VA. Impact of biliary drainage prior to pancreatectomy. Acta Chir Belg 2022; 122:390-395. [PMID: 33929304 DOI: 10.1080/00015458.2021.1920659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 04/18/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND There is still a lack of clarity about the benefits of preoperative biliary drainage (PBD), which was introduced to improve the perioperative outcome in patients with obstructive jaundice caused by a periampullary tumour. The aim of this study was to determine whether operative and postoperative complications increase in patients undergoing PBD during pancreatoduodenectomy (PD). MATERIAL AND METHODS Retrospective examination was made of patients who underwent PBD for a periampullary tumour in our hospital between 2006 and 2014. From these, the patients were identified who had PBD with endoscopic retrograde cholangiopancreatography and these patients were further separated into two groups, as one group of patients with plastic stents and the other group of patients with metallic stents. Patients with pancreas head cancer were also separated into two groups as those who were and were not applied with PBD. The preoperative, intraoperative and postoperative characteristics of the patients were evaluated. RESULTS A total of 123 patients were retrospectively reviewed. Biliary stent placement with PBD was applied to 48 patients, of whom 31 had metallic stents and 17 had plastic stents. In general, there was no difference between the PBD and the non-PBD groups in respect of the preoperative, operative and postoperative results. When patients with tumour of the pancreas head only were examined, the rate of wound infection was higher in the PBD group and there was no difference in the other parameters. Moreover, there was no difference between the patients with metallic stents and those with plastic stents in respect of outcomes. CONCLUSIONS With the exception of wound site infection, although no difference was observed between the PBD and the non-PBD groups based on intraoperative and postoperative complications, because of the distinctive inherent complications of PBD it is essential to manage such patients properly and to carefully select the patients for the PBD procedure.
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Affiliation(s)
- Refik Bademci
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Michael Olusegun Temidayo Talabi
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Pedro Salas
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Manuel Rodríguez Blanco
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Gemma Cerdán Riart
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Jesus Bollo
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
| | - Vicente Artigas Raventós
- Division of Hepatobiliary and Pancreatic Surgery, Department of Surgery, Hospital de la Santa Creu i Sant Pau, University Autònoma de Barcelona, Bellaterra, Spain
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Panikar SS, Sekhar Reddy KC, Gonzalez AL, Ramírez-García G, Rodríguez ÁG, Mondragon Sosa MA, Salas P, Mota-Morales JD. Deep Eutectic Solvent-Enabled Plasmonic Nanocellulose Aerogel: On-Demand Three-Dimensional (3D) SERS Hotspot Based on Collapsing Mechanism. Anal Chem 2022; 94:16470-16480. [DOI: 10.1021/acs.analchem.2c03964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sandeep Surendra Panikar
- Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México
| | - Kolli Chandra Sekhar Reddy
- Centro de Investigación y de Estudios Avanzados (CINVESTAV) Unidad Querétaro, Querétaro, 76230, México
- Department of Electrical and Electronics Engineering, Birla Institute of Technology and Science Pilani Hyderabad Campus, Hyderabad 500078, India
| | - Ana L. Gonzalez
- Instituto de Física, Benemérita Universidad Autónoma de Puebla, Apdo. Post. J-48, Puebla, 72570, México
| | - Gonzalo Ramírez-García
- Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México
| | - Ángel G. Rodríguez
- Coordinación para la Innovación y la Aplicación de la Ciencia y la Tecnología (CIACYT), Universidad Autónoma de San Luis Potosí (UASLP), Álvaro Obregón 64, 78000 San Luis Potosí, S.L.P. México
| | - María Antonieta Mondragon Sosa
- Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México
| | - Pedro Salas
- Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México
| | - Josué D. Mota-Morales
- Centro de Física Aplicada y Tecnología Avanzada (CFATA), Universidad Nacional Autónoma de México (UNAM), Querétaro, 76230, México
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Carreño-Vega O, Vargas-Zamarripa M, Salas P, Ramírez-García G. Poly(allylamine)-copper(II) coordination complex grafted on core@shell upconversion nanoparticles for ultrafast and sensitive determination of the phytohormone salicylic acid in plant extracts. Dalton Trans 2022; 51:11630-11640. [PMID: 35861610 DOI: 10.1039/d2dt01392d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Salicylic acid (SA) is a phenolic phytohormone with critical roles in plant growth regulation and resistance to biotic and abiotic stress. Since low SA concentrations can modulate many plant biochemical responses, innovative analytical tools are required to deeply understand its activity and to control its exogenous application in modern agricultural systems. Herein, a NIR-activated composite based on NaYF4:Yb,Er@NaYF4 core@shell upconversion nanoparticles decorated with the poly(allylamine)-Cu(II) complex [UCNPs-PAAm-Cu(II)] was developed to sensitively determine the SA molecule in plant-derived samples. Accordingly, the PAAm-Cu(II) complex grafted on the UCNPs induces a strategic charge transfer band which triggers a quenching process through a resonance energy transfer (RET) mechanism. Such process is gradually deactivated upon the addition of SA and the consequent formation of the SA-Cu(II) complex, allowing a luminescence recovery in the 1-800 nM linear range. This mechanism is promoted by the strong stability of the SA-Cu(II) complex (log β2-SA/Cu = 19.01) which is over twelve orders of magnitude stronger than the PAAm-Cu2+ counterpart. Furthermore, the equilibrium and kinetic studies on the involved mononuclear Cu2+ complexes formation permitted instantaneous analytical responses and excellent selectivity against other representative phytohormones and metallic cations. The reliability of this method was demonstrated by determining the SA content of some edible fruits and vegetables comprising apple, lemon, kiwi, tomato, and cucumber, whose concentrations ranged from 0.30 to 2.99 μg g-1, with percent recoveries between 94.6 to 102.3%. Thereby, the reported nanocomplex can help to understand the SA activity in plants with significant applications in crop yield improvement and food quality assessment.
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Affiliation(s)
- Osvaldo Carreño-Vega
- Universidad Nacional Autónoma de México. Centro de Física Aplicada y Tecnología Avanzada, Biofunctional Nanomaterials Laboratory. 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico.
| | - Marlene Vargas-Zamarripa
- División de Ciencias e Ingenierías, Universidad de Guanajuato, Av. Juárez 77, C.P. 36000, Guanajuato, Mexico
| | - Pedro Salas
- Universidad Nacional Autónoma de México. Centro de Física Aplicada y Tecnología Avanzada, Biofunctional Nanomaterials Laboratory. 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico.
| | - Gonzalo Ramírez-García
- Universidad Nacional Autónoma de México. Centro de Física Aplicada y Tecnología Avanzada, Biofunctional Nanomaterials Laboratory. 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico.
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Figueroa R, Taramasco C, Flores C, Ortiz L, Vásquez-Venegas C, Salas P, Zeng-Treilter Q. A physician's perspective on the incorporation of pictograms as a supplement to medical instructions in Chile: A pilot study. Ing Rech Biomed 2022. [DOI: 10.1016/j.irbm.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Panikar SS, Banu N, Haramati J, Del Toro-Arreola S, Riera Leal A, Salas P. Nanobodies as efficient drug-carriers: Progress and trends in chemotherapy. J Control Release 2021; 334:389-412. [PMID: 33964364 DOI: 10.1016/j.jconrel.2021.05.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 05/03/2021] [Accepted: 05/04/2021] [Indexed: 01/24/2023]
Abstract
Nanobodies (Nb) have a promising future as a part of next generation chemodrug delivery systems. Nb, or VHH, are small (15 kDa) monomeric antibody fragments consisting of the antigen binding region of heavy chain antibodies. Heavy chain antibodies are naturally produced by camelids, however the structure of their VHH regions can be readily reproduced in industrial expression systems, such as bacteria or yeast. Due to their small size, high solubility, remarkable stability, manipulatable characteristics, excellent in vivo tissue penetration, conjugation advantages, and ease of production, Nb have many advantages when compared against their antibody precursors. In this review, we discuss the generation and selection of Nbs via phage display libraries for easy screening, and the conjugation techniques involved in creating target-specific nanocarriers. Furthermore, we provide a comprehensive overview of recent developments and perspectives in the field of Nb drug conjugates (NDCs) and Nb-based drug vehicles (NDv) with respect to antitumor therapeutics.
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Affiliation(s)
- Sandeep Surendra Panikar
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autonoma de México (UNAM), Apartado Postal 1-1010, Queretaro, Queretaro 76000, Mexico.
| | - Nehla Banu
- Instituto de Enfermedades Crónico-Degenerativas, Departamento de Biología Molecular y Genómica, CUCS, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
| | - Jesse Haramati
- Laboratorio de Inmunobiología, Departamento de Biología Celular y Molecular, CUCBA, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Susana Del Toro-Arreola
- Instituto de Enfermedades Crónico-Degenerativas, Departamento de Biología Molecular y Genómica, CUCS, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico
| | - Annie Riera Leal
- UC Davis Institute for Regenerative Cures, Department of Dermatology, University of California, Davis, 2921 Stockton Blvd, Rm 1630, Sacramento, CA 95817, USA
| | - Pedro Salas
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autonoma de México (UNAM), Apartado Postal 1-1010, Queretaro, Queretaro 76000, Mexico
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Panikar SS, Banu N, Escobar ER, García GR, Cervantes-Martínez J, Villegas TC, Salas P, De la Rosa E. Stealth modified bottom up SERS substrates for label-free therapeutic drug monitoring of doxorubicin in blood serum. Talanta 2020; 218:121138. [DOI: 10.1016/j.talanta.2020.121138] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/05/2020] [Accepted: 05/06/2020] [Indexed: 12/26/2022]
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Ayala‐Fonseca LA, Amieva EJ, Rodriguez‐Gonzalez C, Angeles‐Chavez C, De la Rosa E, Castaño VM, Salas P. Enhanced Raman Effect of Solvothermal Synthesized Reduced Graphene Oxide/Titanium Dioxide Nanocomposites. ChemistrySelect 2020. [DOI: 10.1002/slct.202000335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Luis A. Ayala‐Fonseca
- Centro de Física Aplicada y Tecnología AvanzadaUniversidad Nacional Autónoma de México 3001, Boulevard Juriquilla 76230 Querétaro México
| | - Edgar J.‐C. Amieva
- Centro de Física Aplicada y Tecnología AvanzadaUniversidad Nacional Autónoma de México 3001, Boulevard Juriquilla 76230 Querétaro México
| | - Claramaria Rodriguez‐Gonzalez
- Centro de Física Aplicada y Tecnología AvanzadaUniversidad Nacional Autónoma de México 3001, Boulevard Juriquilla 76230 Querétaro México
| | - Carlos Angeles‐Chavez
- Gerencia de Desarrollo de Materiales y Productos QuímicosInstituto Mexicano del Petróleo eje Central Lázaro Cárdenas No. 152, C.P. 07730 Ciudad de México, México
| | - Elder De la Rosa
- Universidad De La Salle Bajío Campus Campestre León Guanajuato 37150, México
| | - Victor M. Castaño
- Centro de Física Aplicada y Tecnología AvanzadaUniversidad Nacional Autónoma de México 3001, Boulevard Juriquilla 76230 Querétaro México
| | - Pedro Salas
- Centro de Física Aplicada y Tecnología AvanzadaUniversidad Nacional Autónoma de México 3001, Boulevard Juriquilla 76230 Querétaro México
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Ramírez-García G, De la Rosa E, López-Luke T, Panikar SS, Salas P. Controlling trapping states on selective theranostic core@shell (NaYF 4:Yb,Tm@TiO 2-ZrO 2) nanocomplexes for enhanced NIR-activated photodynamic therapy against breast cancer cells. Dalton Trans 2019; 48:9962-9973. [PMID: 31074748 DOI: 10.1039/c9dt00482c] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Photodynamic and immune therapies are innovative medical strategies against cancer, and their integration with upconversion nanoparticles (UCNPs) can improve the diagnosis and treatment of the disease. The UCNPs convert the deep penetrating near-infrared (NIR) light into higher energy emissions, allowing the imaging and detection of malignant cells and the simultaneous energy transfer for activation of the photosensitizers. In this work, the UCNPs were coated with a photocatalytic TiO2/ZrO2 shell and an increase of oxygen defects (VO) was observed as a result of the partial substitution of Ti4+ by Zr4+ ions in the crystalline lattice of TiO2. Such defects act as trapping states improving charge separation and then reducing the recombination rate of the electron-hole pairs (e-/h+) generated upon resonant energy transfer from the donor (UCNPs) to acceptors (shell). The overall results are the enhancement of both ROS production and the emission band centered at 801 nm which is useful for tracking cells at the deep tissue level. However, an excess of those defects produces deleterious effects on both processes as a result of charge migration. The specificity against HER2 positive breast cancer was provided by bioconjugation with the monoclonal antibody trastuzumab. After administration of the synthesized NaYF4:Yb,Tm@TiO2/ZrO2-trastuzumab theranostic nanocomplex doped with an optimal ZrO2 molar concentration (25%) and subsequent exposure to 975 nm light (0.71 W cm-2) during 5 minutes, HER2-positive SKBr3 breast cancer cells were suppressed with 88% drop of the cell viability, 28% higher than UCNPs decorated with a pure TiO2 shell.
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Affiliation(s)
- Gonzalo Ramírez-García
- Cátedras CONACyT-Centro de Investigación en Química Aplicada, COITTEC, Saltillo, Coahuila 25294, Mexico.
| | - Elder De la Rosa
- Universidad De La Salle Bajío, Campus Campestre, León, Guanajuato 37150, Mexico.
| | - Tzarara López-Luke
- Instituto de Investigación en Metalurgia y Materiales, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Morelia, 58030, Mexico
| | - Sandeep S Panikar
- Universidad De La Salle Bajío, Campus Campestre, León, Guanajuato 37150, Mexico. and Centro de Investigación y Asistencia en Tecnología y Diseño del Estado de Jalisco (CIATEJ, A.C.), Medical and Pharmaceutical Biotechnology Department. 800, Av. Normalistas, Guadalajara, Jalisco 44270, Mexico
| | - Pedro Salas
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, 3001, Boulevard Juriquilla, 76230, Querétaro, Mexico
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Cuadrado S, Salas P, Goicoechea JR, Cernicharo J, Tielens AGGM, Báez-Rubio A. Direct estimation of electron density in the Orion Bar PDR from mm-wave carbon recombination lines. Astron Astrophys 2019; 625:10.1051/0004-6361/201935556. [PMID: 31186576 PMCID: PMC6558286 DOI: 10.1051/0004-6361/201935556] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
CONTEXT A significant fraction of the molecular gas in star-forming regions is irradiated by stellar UV photons. In these environments, the electron density (n e) plays a critical role in the gas dynamics, chemistry, and collisional excitation of certain molecules. AIMS We determine n e in the prototypical strongly irradiated photodissociation region (PDR), the Orion Bar, from the detection of new millimeter-wave carbon recombination lines (mmCRLs) and existing far-IR [13Cii] hyperfine line observations. METHODS We detect 12 mmCRLs (including α, β, and γ transitions) observed with the IRAM 30m telescope, at ~ 25″ angular resolution, toward the H/H2 dissociation front (DF) of the Bar. We also present a mmCRL emission cut across the PDR. RESULTS These lines trace the C+/C/CO gas transition layer. As the much lower frequency carbon radio recombination lines, mmCRLs arise from neutral PDR gas and not from ionized gas in the adjacent Hii region. This is readily seen from their narrow line profiles (Δv = 2.6 ± 0.4 km s-1) and line peak velocities (ν LSR = +10.7 ± 0.2 km s-1). Optically thin [13Cii] hyperfine lines and molecular lines - emitted close to the DF by trace species such as reactive ions CO+ and HOC+ - show the same line profiles. We use non-LTE excitation models of [13Cii] and mmCRLs and derive n e = 60 - 100 cm-3 and T e = 500 - 600 K toward the DF. CONCLUSIONS The inferred electron densities are high, up to an order of magnitude higher than previously thought. They provide a lower limit to the gas thermal pressure at the PDR edge without using molecular tracers. We obtain P th ≥ (2 - 4)·108 cm-3 K assuming that the electron abundance is equal to or lower than the gas-phase elemental abundance of carbon. Such elevated thermal pressures leave little room for magnetic pressure support and agree with a scenario in which the PDR photoevaporates.
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Affiliation(s)
- S. Cuadrado
- Instituto de Física Fundamental (IFF-CSIC). Calle Serrano
121-123, E28006 Madrid, Spain
| | - P. Salas
- Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA
Leiden, The Netherlands
| | - J. R. Goicoechea
- Instituto de Física Fundamental (IFF-CSIC). Calle Serrano
121-123, E28006 Madrid, Spain
| | - J. Cernicharo
- Instituto de Física Fundamental (IFF-CSIC). Calle Serrano
121-123, E28006 Madrid, Spain
| | - A. G. G. M. Tielens
- Leiden Observatory, Leiden University, P.O. Box 9513, NL-2300 RA
Leiden, The Netherlands
| | - A. Báez-Rubio
- Centro de Astrobiología (CSIC-INTA), Ctra. de Torrejón
a Ajalvir, km 4, E28850 Torrejón de Ardoz, Madrid, Spain
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Bollo J, Salas P, Martinez MC, Hernandez P, Rabal A, Carrillo E, Targarona E. Intracorporeal versus extracorporeal anastomosis in right hemicolectomy assisted by laparoscopy: study protocol for a randomized controlled trial. Int J Colorectal Dis 2018; 33:1635-1641. [PMID: 30191370 DOI: 10.1007/s00384-018-3157-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/29/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND Colorectal cancer (CRC) is the third most frequent cancer diagnosed in men and the second in women. Laparoscopic surgery has been a technical revolution in colorectal surgery, facilitating a better recovery of patients with lower morbidity and better esthetic results, compared to traditional surgery via laparotomy, without compromising safety and long-term oncological results. PURPOSE The trial is a randomized controlled trial indented to evaluate the two interventions with thorough measurements of the postoperative variables and complications to improve the evaluation of the surgical technique. The primary endpoint is to compare the hospital stay, which will be measured in days between both groups. The purpose of the study at secondary endpoints is to compare intraoperative and postoperative events between both groups in terms of operating time, anastomotic performance time, intraoperative complications, number of harvested lymph nodes, need for blood transfusion, length of the surgical wound, start and tolerance of oral intake, beginning of digestive functionality, postoperative pain, need for analgesic administration, surgical wound infection, paralytic ileus, anastomosis leakage or dehiscence, need for surgical reintervention, and hospital readmission within the first 30 days after surgery. METHODS This trial is a prospective, randomized, single-blind, and single-center clinical trial comparing intracorporeal anastomosis versus extracorporeal anastomosis for right laparoscopic hemicolectomy. CONCLUSIONS Nowadays, there are several retrospective trials comparing the benefits for extracorporeal anastomosis versus intracorporeal anastomosis in right colon cancer patients. Considering the impact for laparoscopic surgery, we think it is necessary to do a randomized trial comparing extracorporeal versus intracorporeal anastomosis modalities. TRIAL REGISTRATION www.clinicaltrials.gov No. NCT02667860 and Hospital de la Santa Creu i Sant Pau Research Institute No. IIBSP-AIE-2015-01.
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Affiliation(s)
- J Bollo
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain.
| | - P Salas
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
| | - M C Martinez
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
| | - P Hernandez
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
| | - A Rabal
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
| | - E Carrillo
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
| | - E Targarona
- Department of Medicine of the Autonomous University of Barcelona, Hospital de la Santa Creu i Sant Pau, Carrer de Sant Quintí, 89, 08041, Barcelona, Spain
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Rodríguez-González C, Velázquez-Villalba P, Salas P, Castaño VM. Green synthesis of nanosilver-decorated graphene oxide sheets. IET Nanobiotechnol 2016; 10:301-307. [PMID: 27676378 PMCID: PMC8676033 DOI: 10.1049/iet-nbt.2015.0043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 01/25/2016] [Accepted: 02/18/2016] [Indexed: 09/22/2023] Open
Abstract
A green facile method has been successfully used for the synthesis of graphene oxide sheets decorated with silver nanoparticles (rGO/AgNPs), employing graphite oxide as a precursor of graphene oxide (GO), AgNO3 as a precursor of Ag nanoparticles (AgNPs), and geranium (Pelargonium graveolens) extract as reducing agent. Synthesis was accomplished using the weight ratios 1:1 and 1:3 GO/Ag, respectively. The synthesised nanocomposites were characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction, UV-visible spectroscopy, Raman spectroscopy, energy dispersive X-ray spectroscopy and thermogravimetric analysis. The results show a more uniform and homogeneous distribution of AgNPs on the surface of the GO sheets with the weight ratio 1:1 in comparison with the ratio 1:3. This eco-friendly method provides a rGO/AgNPs nanocomposite with promising applications, such as surface enhanced Raman scattering, catalysis, biomedical material and antibacterial agent.
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Affiliation(s)
- Claramaría Rodríguez-González
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, 76230 Juriquilla, Querétaro, México
| | - Pamela Velázquez-Villalba
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, 76230 Juriquilla, Querétaro, México
| | - Pedro Salas
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, 76230 Juriquilla, Querétaro, México
| | - Víctor M Castaño
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Boulevard Juriquilla 3001, 76230 Juriquilla, Querétaro, México.
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Perez-Mayen L, Oliva J, Salas P, De la Rosa E. Nanomolar detection of glucose using SERS substrates fabricated with albumin coated gold nanoparticles. Nanoscale 2016; 8:11862-11869. [PMID: 27230115 DOI: 10.1039/c6nr00163g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This work presents the design of substrates for Surface Enhanced Raman Scattering (SERS) using star-like gold nanoparticles synthesized by a wet chemical method. The SERS substrates were used for glucose detection for concentrations as low as 10(-7) M, which represents an enhancement factor (EF) of 10(9), as a result of the hot spot formed by the spike termination and appropriate distribution of the gold nanoparticles. An improvement of two orders of magnitude was obtained by coating the gold nanoparticles with albumin with the configuration: glass/Au nanoparticles/albumin. In this case the lowest detection was at a concentration of 10(-9) M for an EF of 10(11). The albumin molecule allowed us to enhance the Raman signal because of the formation of peptide bonds (COOH-NH2) generated due to the interaction of glucose with albumin, and the appropriate separation distance between the glucose molecules and gold nanoparticles. The presence of such peptide conjugates was confirmed by FTIR spectra. Thus, our results suggest that our SERS substrates can be useful for the detection of very low concentrations of glucose, which is important for the diagnosis of diabetes in the field of medicine.
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Affiliation(s)
| | - Jorge Oliva
- Centro de Investigaciones en Óptica A.C., A.P. 1-948, León, Gto 37160, México.
| | - P Salas
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, A.P. 1-1010, Querétaro, Qro. 76000, México
| | - Elder De la Rosa
- Centro de Investigaciones en Óptica A.C., A.P. 1-948, León, Gto 37160, México.
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Cepeda-Pérez E, López-Luke T, Salas P, Plascencia-Villa G, Ponce A, Vivero-Escoto J, José-Yacamán M, de la Rosa E. SERS-active Au/SiO2 clouds in powder for rapid ex vivo breast adenocarcinoma diagnosis. Biomed Opt Express 2016; 7:2407-18. [PMID: 27375955 PMCID: PMC4918593 DOI: 10.1364/boe.7.002407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/27/2016] [Accepted: 05/17/2016] [Indexed: 05/26/2023]
Abstract
In the present work, we report a dry-based application technique of Au/SiO2 clouds in powder for rapid ex vivo adenocarcinoma diagnosis through surface-enhanced Raman scattering (SERS); using low laser power and an integration time of one second. Several characteristic Raman peaks frequently used for the diagnosis of breast adenocarcinoma in the range of the amide III are successfully enhanced by breading the tissue with Au/SiO2 powder. The SERS activity of these Au/SiO2 powders is attributed to their rapid rehydration upon contact with the wet tissues, which promotes the formation of gold nanoparticle aggregates. The propensity of the Au/SiO2 cloud structures to adsorb biomolecules in the vicinity of the gold nanoparticle clusters promotes the necessary conditions for SERS detection. In addition, electron microscopy, together with elemental analysis, have been used to confirm the structure of the new Au/SiO2 cloud material and to investigate its distribution in breast tissues.
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Affiliation(s)
| | | | - Pedro Salas
- Universidad Nacional Autónoma de México, Centro de Física Aplicada y Tecnología Avanzada, Querétaro 76000, Mexico
| | - Germán Plascencia-Villa
- Department of Physics and Astronomy, The University of Texas at San Antonio (UTSA), One UTSA Circle, San Antonio, USA
| | - Arturo Ponce
- Department of Physics and Astronomy, The University of Texas at San Antonio (UTSA), One UTSA Circle, San Antonio, USA
| | - Juan Vivero-Escoto
- Department of Chemistry, The University of North Carolina at Charlotte, 9201 University City Blvd. Charlotte, NC 28223, USA
| | - Miguel José-Yacamán
- Department of Physics and Astronomy, The University of Texas at San Antonio (UTSA), One UTSA Circle, San Antonio, USA
| | - Elder de la Rosa
- Centro de Investigaciones en Óptica, León, Gto., C.P. 37150, Mexico
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Hyun J, Romero L, Riveron R, Flores C, Kanagavelu S, Chung KD, Alonso A, Sotolongo J, Ruiz J, Manukyan A, Chun S, Singh G, Salas P, Targan SR, Fukata M. Human intestinal epithelial cells express interleukin-10 through Toll-like receptor 4-mediated epithelial-macrophage crosstalk. J Innate Immun 2014; 7:87-101. [PMID: 25171731 DOI: 10.1159/000365417] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/23/2014] [Indexed: 12/12/2022] Open
Abstract
In the intestine, interaction between epithelial cells and macrophages (MΦs) create a unique immunoregulatory microenvironment necessary to maintain local immune and tissue homeostasis. Human intestinal epithelial cells (IECs) have been shown to express interleukin (IL)-10, which keeps epithelial integrity. We have demonstrated that bacterial signaling through Toll-like receptor (TLR) 4 induces 15-deoxy-Δ-12,14-prostaglandin J2 (15d-PGJ2) synthesis in intestinal MΦs by cyclooxygenase (Cox)-2 expression. Here, we show that TLR4 signaling generates crosstalk between IECs and MΦs that enhances IL-10 expression in IECs. Direct stimulation of TLR4 leads to the expression of IL-10 in IECs, while the presence of MΦs in a Transwell system induces another peak in IL-10 expression in IECs at a later time point. The second peak of the IL-10 expression is two times greater than the first peak. This late induction of IL-10 depends on the nuclear receptor peroxisome proliferator-activated receptor (PPAR) γ that is accumulated in IECs by TLR4-mediated inhibition of the ubiquitin-proteasomal pathway. TLR4 signaling in MΦs in turn synthesizes 15d-PGJ2 through p38 and ERK activation and Cox-2 induction, which activates PPARγ in IECs. These results suggest that TLR4 signaling maintains IL-10 production in IECs by generating epithelial-MΦs crosstalk, which is an important mechanism in the maintenance of intestinal homeostasis mediated through host-bacterial interactions.
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Affiliation(s)
- Jinhee Hyun
- Division of Gastroenterology, Department of Medicine, University of Miami Miller School of Medicine, Miami, Fla., USA
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Caliz R, Ferrer MA, Soto MJ, Garcia A, Utrilla A, Salas P, Lopez-Sidro M, Romani L, Acevedo Z, Notario I, Sainz J, Cáliz R. FRI0183 Long-term survival of tumor necrosis factor-alpha inhibitor therapies in a spanish cohort of rheumatoid arthritis patients. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Haller M, Van Biesen W, Webster AC, Vanholder R, Nagler EV, Lee JE, Kim SK, Park SK, Yun GY, Choi HY, Ha SK, Park HC, Hernandez-Sevillano B, Rodriguez JR, Perez del Valle K, de Lorenzo A, Salas P, Bienvenido M, Sanchez-Heras M, Basterrechea MA, Tallon S, de Arriba G, Greenberg A, Verbalis J, Burst V, Haymann JP, Poch E, Chiodo J, Nagler EV, Vanmassenhove J, van der Veer SN, Nistor I, Van Biesen W, Webster AC, Vanholder R, Pignataro A, Alfieri V, Cesano G, Timbaldi M, Torta E, Boero R, Nagler EV, Haller MC, Van Biesen W, Vanholder R, Webster AC, Cucchiari D, Podesta M, Merizzoli E, Angelini C, Badalamenti S, Alves MT, Moyses RM, Jorgetti V, Heilberg I, Menon V, Lhotta K, Muendlein A, Meusburger E, Zitt E, Bijarnia R, Pasch A, Hwang SW, Lee CH, Kim GH, Leckstrom D, Pereira C, Bultitude M, McGrath A, Goldsmith DJ, Vasquez D, Fernandez B, Palomo S, Aller C, Gordillo R, Perez V, Bustamante J, Coca A, Vitale C, Bagnis C, Tricerri A, Gallo L, Dutto F, Migliardi M, Marangella M, Outerelo C, Figueiredo P, Freitas J, Teixeira Costa F, Ramos A, Rambod M, Melikterminas E, Atallah H, Saadi M, Connery S, Mulla Z, Tolouian R, Cristofaro R, Masola V, Ceol M, Priante G, Familiari A, Gambaro G, Anglani F. Acid-base / electrolytes / nephrolithiasis. Nephrol Dial Transplant 2013. [DOI: 10.1093/ndt/gft139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Romero V, De la Rosa E, Salas P, Velázquez-Salazar J. Strong blue and white photoluminescence emission of BaZrO3 undoped and lanthanide doped phosphor for light emitting diodes application. J SOLID STATE CHEM 2012. [DOI: 10.1016/j.jssc.2012.06.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gattas MV, Forteza R, Fragoso MA, Fregien N, Salas P, Salathe M, Conner GE. Oxidative epithelial host defense is regulated by infectious and inflammatory stimuli. Free Radic Biol Med 2009; 47:1450-8. [PMID: 19703552 PMCID: PMC2767478 DOI: 10.1016/j.freeradbiomed.2009.08.017] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/05/2009] [Accepted: 08/19/2009] [Indexed: 12/15/2022]
Abstract
Epithelia express oxidative antimicrobial protection that uses lactoperoxidase (LPO), hydrogen peroxide (H(2)O(2)), and thiocyanate to generate the reactive hypothiocyanite. Duox1 and Duox2, found in epithelia, are hypothesized to provide H(2)O(2) for use by LPO. To investigate the regulation of oxidative LPO-mediated host defense by bacterial and inflammatory stimuli, LPO and Duox mRNA were followed in differentiated primary human airway epithelial cells challenged with Pseudomonas aeruginosa flagellin or IFN-gamma. Flagellin upregulated Duox2 mRNA 20-fold, but upregulated LPO mRNA only 2.5-fold. IFN-gamma increased Duox2 mRNA 127-fold and upregulated LPO mRNA 10-fold. DuoxA2, needed for Duox2 activity, was also upregulated by flagellin and IFN-gamma. Both stimuli increased H(2)O(2) synthesis and LPO-dependent killing of P. aeruginosa. Reduction of Duox1 by siRNA showed little effect on basal H(2)O(2) production, whereas Duox2 siRNA markedly reduced basal H(2)O(2) production and resulted in an 8-fold increase in Nox4 mRNA. In conclusion, large increases in Duox2-mediated H(2)O(2) production seem to be coordinated with increases in LPO mRNA and, without increased LPO, H(2)O(2) levels in airway secretion are expected to increase substantially. The data suggest that Duox2 is the major contributor to basal H(2)O(2) synthesis despite the presence of greater amounts of Duox1.
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Affiliation(s)
| | - Radia Forteza
- Department of Cell Biology and Anatomy, University of Miami, Miami, FL 33136 USA
| | - Miryam A. Fragoso
- Department of Cell Biology and Anatomy, University of Miami, Miami, FL 33136 USA
| | - Nevis Fregien
- Department of Cell Biology and Anatomy, University of Miami, Miami, FL 33136 USA
| | - Pedro Salas
- Department of Cell Biology and Anatomy, University of Miami, Miami, FL 33136 USA
| | - Matthias Salathe
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
| | - Gregory E. Conner
- Department of Cell Biology and Anatomy, University of Miami, Miami, FL 33136 USA
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
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Angeles-Chavez C, Salas P, Díaz-Torres LA, de la Rosa E, Esparza R, Perez R. Structural and chemical characterization of Yb2O3-ZrO2 system by HAADF-STEM and HRTEM. Microsc Microanal 2009; 15:46-53. [PMID: 19144257 DOI: 10.1017/s1431927609090047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
ZrO2:Yb3+ nanocrystalline phosphors with high concentrations of ytterbium ions were prepared using the sol-gel method. X-ray diffraction, high-angle annular-dark-field scanning transmission electron microscopy (HAADF-STEM), energy dispersive X-ray spectroscopy, and high-resolution transmission electron microscopy (HRTEM) were used to characterize the nanocrystalline phosphors annealed at 1000 degrees C. Unit-cell distortion and changes in the crystalline structure of the monoclinic zirconia to tetragonal zirconia, and subsequently cubic zirconia, were observed with increased Yb concentration. Yb ions were randomly distributed into the lattice of the crystalline structure. No segregation of Yb2O3 phase was observed. The substitution of Zr atoms by Yb atoms on different crystalline phases was confirmed by the experimental results and theoretical simulations of HRTEM and HAADF-STEM.
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Affiliation(s)
- C Angeles-Chavez
- Instituto Mexicano del Petroleo, Programa de Ingeniería Molecular, Eje Central Lazaro Cardenas 152, A. P. 14-805, 07730 México, D. F. Mexico.
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Diaz-Torres LA, Salas P, Perez-Huerta JS, Angeles-Chavez C, De la Rosa E. A new blue, green and red upconversion emission nanophosphor: BaZrO3:Er,Yb. J Nanosci Nanotechnol 2008; 8:6425-6430. [PMID: 19205216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Strong Blue, green, and red upconversion emission of Er3+ in nanocrystalline BaZrO3:(Yb3+Er3+) is observed. Powder samples were obtained by a facile hydrothermal process at 100 degrees C. The as synthesized nanocrystallites preserve a stable cubic perovskite phase under subsequent annealing treatment up to 1000 degrees C. No other phase or segregation of other compounds was detected. Crystallites sizes were around 115 nm and well faceted. Under IR excitation in the range between 900 and 1050 nm the Er3+ blue emission was almost not present in single Er3+ doped BaZrO3, whereas it became easily observable when Yb3+ was added as codopant. Besides, both green and red upconversion emission or upconverted signal of Er3+ are enhanced by around three orders of magnitude in comparison with the single Er3+ doped BaZrO3. The strong blue emission presents dependence on both excitation power and excitation wavelength. This is the first time that upconversion emission is observed in BaZrO3. A possible mechanism for the upconversion process that leads to the observed blue, green and red emissions under NIR excitation is suggested based on the experimental results.
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Affiliation(s)
- L A Diaz-Torres
- Centro de Investigaciones en Optica A.C., Leon, Gto. 37150 Mexico
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Rodríguez RA, De la Rosa E, Romero VH, Meléndrez R, Salas P, Diaz-Torres LA, Barboza-Flores M. Thermoluminescence properties of undoped and Dy3+ doped ZrO2 nanophosphor under beta-ray irradiation. J Nanosci Nanotechnol 2008; 8:6419-6424. [PMID: 19205215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The thermoluminescence (TL) of undoped and Dy3+ doped ZrO2 nanocrystals under beta-ray irradiation is reported. The TL glow curves are the result of the overlapping of four TL peaks produced partly by the intrinsic defect of highly asymmetrical monoclinic structure and partly due to defects produced during the synthesis process. The introduction of dopant ions induces changes in the glow curve due to the enhancement of high temperature peaks intensity. The results show that both undoped and doped ZrO2 nanocrystalline phosphor present good TL efficiency as well as good dose response which qualify them as a potential beta-ray dosimeter.
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Affiliation(s)
- R A Rodríguez
- Universidad de Guadalajara, Unidad Lagos, Lagos de Moreno, Jal. 47460, México
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Salas P, Nava N, Angeles-Chavez C, De la Rosa E, Díaz-Torres LA. Structural and spectroscopic characterization of ZrO2:Eu3+ nanoparticles. J Nanosci Nanotechnol 2008; 8:6431-6436. [PMID: 19205217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
ZrO2:Eu3+ nanocrystals were prepared by the sol-gel technique. The structural and luminescence properties of europium doped zirconia with 0.5 to 2 mol% were studied by Mössbauer spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and photoluminescence (PL) under UV excitation. Structural characterization shows a crystallite size between 16 to 55 nm and monoclinic and tetragonal zirconia phases as the main crystalline structure. XRD patterns shown that the content of the active ions stabilizes the tetragonal structure of ZrO2 at 1000 degrees C, being 100% for 2 mol% Eu2O3 doped sample. Such results are in agreement with HRTEM and Raman spectroscopy. The Mössbauer spectra of the ZrO2:Eu3+ samples show a single peak near zero velocity which is attributed to Eu+3. Luminescence characterization shows the typical emission band centered at 595 and 611 nm. Change in the structure of such band was observed and explained in terms of crystalline phase change. The dependence between the fluorescence emission and the crystalline structure is discussed.
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Affiliation(s)
- P Salas
- Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, A. P 1-1010, Querétaro, Qro. 76000, México
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Catanuto P, Espinosa-Heidmann D, Pereira-Simon S, Sanchez P, Salas P, Hernandez E, Cousins SW, Elliot SJ. Mouse retinal pigmented epithelial cell lines retain their phenotypic characteristics after transfection with human papilloma virus: a new tool to further the study of RPE biology. Exp Eye Res 2008; 88:99-105. [PMID: 19013153 DOI: 10.1016/j.exer.2008.10.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 10/15/2008] [Accepted: 10/16/2008] [Indexed: 11/26/2022]
Abstract
Development of immortalized mouse retinal pigmented epithelial cell (RPE) lines that retain many of their in vivo phenotypic characteristics, would aid in studies of ocular diseases including age related macular degeneration (AMD). RPE cells were isolated from 18-month-old (estrogen receptor knockout) ERKOalpha and ERKObeta mice and their C57Bl/6 wildtype littermates. RPE65 and cellular retinaldehyde binding protein (CRALBP) expression, in vivo markers of RPE cells, were detected by real-time RT-PCR and western analysis. We confirmed the presence of epithelial cell markers, ZO1, cytokeratin 8 and 18 by immunofluorescence staining. In addition, we confirmed the distribution of actin filaments and the expression of ezrin. To develop cell lines, RPE cells were isolated, propagated and immortalized using human papilloma virus (HPV) 16 (E6/E7). RPE-specific markers and morphology were assessed before and after immortalization. In wildtype littermate controls, there was no evidence of any alterations in the parameters that we examined including MMP-2, TIMP-2, collagen type IV, and estrogen receptor (ER)alpha and ERbeta protein expression and ER copy number ratio. Therefore, immortalized mouse RPE cell lines that retain their in vivo phenotype can be isolated from either pharmacologically or genetically manipulated mice, and may be used to study RPE cell biology.
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Affiliation(s)
- Paola Catanuto
- Department of Surgery, University of Miami, Miller School of Medicine, Miami, Florida 33136, USA.
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27
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Chen L, Noreña L, Wang J, Zhou X, Navarrete J, Hernández I, Montoya A, Romo PP, Salas P, Pergher SC. A study of n-hexane hydroisomerization catalyzed with the Pt/H3PW12O40/Zr-MCM-41 catalysts. Catal Today 2008. [DOI: 10.1016/j.cattod.2007.12.115] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Diaz-Torres L, De la Rosa E, Salas P, Romero V, Angeles-Chávez C. Efficient photoluminescence of Dy3+ at low concentrations in nanocrystalline ZrO2. J SOLID STATE CHEM 2008. [DOI: 10.1016/j.jssc.2007.09.033] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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29
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Salas P, Oyarzo-Llaipen JC, Wang D, Chase K, Mansur L. Genetic mapping of seed shape in three populations of recombinant inbred lines of soybean (Glycine max L. Merr.). Theor Appl Genet 2006; 113:1459-66. [PMID: 17036219 DOI: 10.1007/s00122-006-0392-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 08/06/2006] [Indexed: 05/12/2023]
Abstract
Round soybean seeds are sought-after for food-type soybean. Also the genetic control of seed geometry is of scientific interest. The objectives of this study were to estimate heritability and map quantitative trait loci (QTLs) responsible for seed shape traits. Three densely mapped recombinant inbred populations each with 192 segregants were used, Minsoy x Archer, Minsoy x Noir1, and Noir1 x Archer. A two rep two location experiment was conducted in Los Andes, Chile, and East Lansing, MI, USA. Seed height (SH), width (SW), length (SL), and seed volume (SV) as width x height x length were measured to determine seed shape. Heritability was estimated by variance component analysis. A total of 19 significant QTLs (LOD >or= 3.7) in ten linkage groups (LG) were detected for all the traits. Only one QTL was stable across populations and environments and six were stable in at least two populations in both environments. The amount of phenotypic variation explained by a single QTL varied from 7.5% for SH, to 18.5% for SW and at least 30% of the genetic variation for the traits is controlled by four QTL or less. All traits were highly correlated with each other in all populations with values ranging from 0.5 to 0.9, except for SL and SW that were not significantly correlated or had a low correlation in all populations. Narrow sense heritabilities for all traits ranged from 0.42 to 0.88. We note that LG u9, u11, and u14 are hot points of the genome for QTLs for various traits. The number and genomic distribution of the QTLs confirms the complex genetic control of seed shape. Transgressive segregation was observed for all traits suggesting that careful selection of parents with similar phenotypes but different genotypes using molecular markers can result in desirable transgressive segregants.
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Affiliation(s)
- P Salas
- Facultad de Agronomía, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
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Tagle LH, Diaz FR, Salas P. Polymerization by Phase‐Transfer Catalysis. 8. Synthesis and Characterization of Polythiocarbonates from Diphenols with Methyl Groups. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/00222338908052051] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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31
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Pino V, Ramsauer VP, Salas P, Carothers Carraway CA, Carraway KL. Membrane Mucin Muc4 Induces Density-dependent Changes in ERK Activation in Mammary Epithelial and Tumor Cells. J Biol Chem 2006; 281:29411-20. [PMID: 16891313 DOI: 10.1074/jbc.m604858200] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The membrane mucin Muc4 has been shown to alter cellular behavior through both anti-adhesive effects on cell-cell and cell-extracellular matrix interactions and its ability to act as an intramembrane ligand for the receptor tyrosine kinase ErbB2. The ERK pathway is regulated by both cell-matrix and cell-cell adhesion. An analysis of the effects of Muc4 expression on ERK phosphorylation in mammary tumor and epithelial cells, which exhibit both adhesion-dependent growth and contact inhibition of growth, showed that the effects are density dependent, with opposing effects on proliferating cells and contact-inhibited cells. In these cells, cell-matrix interactions through integrins are required for activation of the ERK mitogenesis pathway. However, cell-cell interactions via cadherins inhibit the ERK pathway. Expression of Muc4 reverses both of these effects. In contact-inhibited cells, Muc4 appears to activate the ERK pathway at the level of Raf-1; this activation does not depend on Ras activation. The increase in ERK activity correlates with an increase in cyclin D(1) expression in these cells. This abrogation of contact inhibition is dependent on the number of mucin repeats in the mucin subunit of Muc4, indicative of an anti-adhesive effect. The mechanism by which Muc4 disrupts contact inhibition involves a Muc4-induced relocalization of E-cadherin from adherens junctions at the lateral membrane of the cells to the apical membrane. Muc4-induced abrogation of contact inhibition may be an important mechanism by which tumors progress from an early, more benign state to invasiveness.
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Affiliation(s)
- Vanessa Pino
- Departments of Cell Biology and Anatomy and Biochemistry and Molecular Biology, University of Miami School of Medicine, Miami, Florida 33101, USA
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Pino V, Salas P, Carraway CAC, Carraway KL. Membrane Mucin Muc4 Induces Density Dependent Changes in Erk Activation in Mammary Epithelial and Tumor Cells. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a510-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Vanessa Pino
- Biochemistry and Molecular BiologyUniversity of Miami School of Medicine1550 NW 10th AveMiamiFL33136
| | - Pedro Salas
- University of Miami School of Medicine1600 NW 10th AveMiamiFL33136
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De la Rosa E, Salas P, Díaz-Torres LA, Martínez A, Angeles C. Strong visible cooperative up-conversion emission in ZrO2:Yb3+ nanocrystals. J Nanosci Nanotechnol 2005; 5:1480-6. [PMID: 16193961 DOI: 10.1166/jnn.2005.320] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Blue, green, and red emission was observed under infrared excitation in ZrO2:Yb3+ nanocrystals prepared by the sol-gel process. The structural characterization was performed by using XRD and HRTEM, suggesting that the crystalline phase of the nanoparticles is controlled by the active ion concentration being mainly tetragonal for 2 mol% of dopant and mainly monoclinic for 0.5 mol%. The blue emission was explained in terms of the cooperative deexcitation of an Yb-Yb pair, while the green and red bands were associated with the up-conversion of traces of Er ion. The number of photons involved in the luminescence process is analyzed in order to confirm that cooperative emission is produced by the interaction of an Yb pair and that the green and red emission are the results of energy transfer between Yb-Er ions. The high efficiency of all bands is explained in terms of the high surface area of the nanoparticles.
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Affiliation(s)
- E De la Rosa
- Centro de Investigaciones en Optica, A.P. 1-948, León Gto, 37160, Mexico
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34
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Rosati P, Pinto V, Delucchi A, Salas P, Cano F, Zambrano P, Lagos E, Rodriguez E, Hevia P, Ramirez K, Quiero X, Azócar M, Rodriguez S, Aguiló J, Varela M, Ferrario M, Ramirez R, Palacios JM, Turu I, Jimenez O, Godoy J, Gaete J, Maluenda X, Villegas R. Pediatric Renal Transplantation: 13 Years of Experience—Report From The Chilean Cooperative Multicenter Group. Transplant Proc 2005; 37:1569-73. [PMID: 15866676 DOI: 10.1016/j.transproceed.2004.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Between 1989 and 2002, 178 renal transplants were performed in 168 pediatric patients in Chile. The mean age was 10.9 +/- 3.7 years (range 1 to 17.9). End-state renal disease etiologies were: congenital renal hypoplasia/dysplasia, chronic glomerulonephritis, and reflux nephropathy. Seventy received a graft from a living donor (LD), and 108 from a cadaveric donor (CD). Only 9% received antibody induction. Acute rejection episodes were reported in 76 patients: 38% in LD recipients and 48% in CD recipients (P = NS). One-, 3-, and 5-year graft survivals were 88%, 84%, and 76%, respectively, for LD and 86%, 79%, and 68% for CD recipients. Actuarial graft survival was significantly better among those patients with serum creatinine < 1 mg/dL at 1 year posttransplant compared with those with creatinine > 1 mg/dL (P < .05). The graft survival rate has improved from the first period (1989 to 1996) to the second period (1997 to 2002); (P = .05). Patient survival rates at 1, 3, and 5 years were 98%, 98%, and 98%, respectively, for LD, and 95%, 94%, and 94% for CD. Global height/age Z-score decreased from -0.7 at birth to -1.5 when dialysis started, and to -2.4 at the time of transplantation. The Z-score height/age at 1, 3, and 5 years posttransplantation was -2.25, -2.24, and -2.5. No significant differences were observed in transplant outcomes comparing patients younger than 7 years with those older ones. In conclusion, pediatric renal transplant has been performed in Chile with acceptable morbidity. The patient and graft survivals are similar to the reported international experience. In the last period there was a significant improvement in graft survival.
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Affiliation(s)
- P Rosati
- University of Chile, School of Medicine, Santiago, Chile.
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35
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Abstract
The results of transmission electron microscopy and thermoluminescence (TL) studies in silica samples containing Fe and Cu nanosized particles show an important enhancement of their TL response when compared with known reports for pure silica samples. The effect of surface electronic states in the nanoparticles, interacting with the matrix, may be responsible for this new size-dependent effect.
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Affiliation(s)
- D Mendoza-Anaya
- Instituto Nacional de Investigaciones Nucleares, km 36.5 Carretera México-Toluca, Ocoyoacac, Edo. de México 52045, Mexico
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36
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Salas P, De la Rosa-Cruz E, Diaz-Torres L, Castaño V, Meléndrez R, Barboza-Flores M. Monoclinic ZrO2 as a broad spectral response thermoluminescence UV dosemeter. RADIAT MEAS 2003. [DOI: 10.1016/s1350-4487(02)00174-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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37
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Arraga-Alvarado C, Palmar M, Parra O, Salas P. Ehrlichia platys (Anaplasma platys) in dogs from Maracaibo, Venezuela: an ultrastructural study of experimental and natural infections. Vet Pathol 2003; 40:149-56. [PMID: 12637754 DOI: 10.1354/vp.40-2-149] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Since 1982 Ehrlichia platys, now emended as Anaplasma platys, has been diagnosed in dogs from Maracaibo, Venezuela, using buffy coat smears stained with Dip Quick. Three dogs were inoculated with an A. platys strain. When parasitemia reached 60-97%, blood samples obtained from the inoculated dogs and from two naturally infected dogs were centrifuged to obtain platelet-rich plasma, which was mixed with 0.1% glutaraldehyde at 37 C for 10 minutes. Platelet pellets were fixed in 3% glutaraldehyde for 72 hours and processed for conventional transmission electron microscopy. Platelets contained pleomorphic organisms with a distinct double membrane that was not observed when the bodies were in a determinate developmental stage. There were 1-15 individual bodies included in a host cell vacuole. The organisms had an electron-lucent inner area, whereas the internal surface of their inner plasma membranes exhibited an electron-dense rough substance. In naturally infected dogs, organisms with different ultrastructural features were found inside the same platelet. Some organisms contained central dense material surrounded by a pale zone, which was in turn surrounded by a moderately dense peripheral area. Other organisms contained an eccentrically electron-dense material. The intravacuolar space appeared fully electron-lucent. Each organism usually exhibited inner fine strands. Empty structures displaying junctions with the vacuolar membrane were observed. Our results indicate that distinct ultrastructural characteristics are associated with different stages of A. platys development and may differ among A. platys strains.
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Affiliation(s)
- C Arraga-Alvarado
- Unidad de Investigacioned Clínicas-Facultad de Ciencias Veterinarias, Universidad del Zulia, Maracaibo, Venezuela.
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38
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Hott HH, Ibanez C, Puente R, Guzman S, Salas P. EFFECTIVENESS OF THE LOOP ELECTROCHIRURGICAL EXCISION PROCEDURE (LEEP) APPLIED TO SOUTHERN CHILEAN WOMEN WITH INTRAEPITHELIAL NEOPLASIA OF THE UTERINE CERVIX. Int J Gynecol Cancer 2003. [DOI: 10.1136/ijgc-00009577-200303001-00360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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39
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Pedrero M, Salas P, Gálvez R, Manuel de Villena FJ, Pingarrón JM. Ruthenium and ruthenium dioxide-modified graphite-ethylene/ propylene/diene and graphite-teflon composite electrodes as amperometric flow detectors. Application to the determination of methionine. Fresenius J Anal Chem 2001; 371:507-13. [PMID: 11760061 DOI: 10.1007/s002160101032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The flow injection amperometric performance of solid composite graphite electrodes with ethylene/propylene/diene (EPD) or Teflon as binding agents, and with Ru or RuO2 particles as electrocatalytic modifiers has been compared. Both, Ru and RuO2 modified electrodes exhibited electrocatalytic properties on the methionine oxidation process in alkaline media. The electrodes composition and the hydrodynamic and chemical variables were optimized. Graphite-EPD (GEPD) electrodes showed a better analytical performance than graphite-Teflon (GPTFE) electrodes. Furthermore, a better sensitivity, repeatability and reproducibility was observed for RuO2-GEPD electrodes when compared with Ru-GEPD electrodes. At an applied potential of +0.50 V, a detection limit for methionine of 4.8x10(-5) mol L(-1), similar to those reported in the literature for other RuO2-modified electrodes, was obtained. The analytical applicability of RuO2-GEPD electrodes was demonstrated by determining methionine in a complex pharmaceutical formulation.
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Affiliation(s)
- M Pedrero
- Departamento de Química Analítica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Spain
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40
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Delucchi A, Marin V, Trabucco G, Azócar M, Salas P, Gutierrez E, Guardia S, Cano F, Cumsille MA. Dyslipidemia and dietary modification in Chilean renal pediatric transplantation. Transplant Proc 2001; 33:2008-13. [PMID: 11267605 DOI: 10.1016/s0041-1345(00)02770-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- A Delucchi
- Division of Pediatric Nephrology Hospital Luis Calvo Mackenna, Exequiel Gonzalez Cortes, Gustavo Fricke, San Juan de Dios, Santiago, Chile
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41
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Delucchi A, Marín V, Trabucco G, Azócar M, Salas P, Gutierrez E, Guardia S, Cano F, Cumsille MA. Dyslipidemia and dietary modification in Chilean renal pediatric transplantation. Transplant Proc 2001; 33:1297-301. [PMID: 11267300 DOI: 10.1016/s0041-1345(01)01915-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- A Delucchi
- Division of Pediatric Nephrology, Hospital Luis Calvo Mackenna, Exequiel Gonzalez Cortes, Gustavo Fricke, San Juan De Dios, Chile.
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Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP and cGMP-regulated chloride channel critical to the regulation of intestinal fluid, chloride, and bicarbonate secretion. In cystic fibrosis (CF), mutations in CFTR result in downregulation of CFTR function and small intestinal obstruction. Unlike the human CF intestine, severe gastrointestinal disease and lethal obstruction is common in transgenic mice deficient in CFTR. The relevance of the physiology of CFTR and pathophysiology of CF in genetically altered mice to that of human CF disease remains incompletely understood. We hypothesized that the expression and distribution of CFTR in mouse intestine may differ from that of human and may contribute to the variation in disease expression between the two species. Using immunocytochemical and immunoblot techniques and well-characterized anti-rodent anti-CFTR antibodies, we examined the cellular distribution of CFTR in the mouse intestinal tract. We identified significant differences in villus distribution for CFTR in the mouse proximal small intestine compared to those previously reported for human and rat. These observations are important to the understanding of CFTR pathophysiology in transgenic CF mouse model systems and bear relevance to the different phenotypic expression of disease in mice compared to human.
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Affiliation(s)
- N Ameen
- Department of Pediatrics, University of Miami School of Medicine, MCCD, FL 33136, USA.
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43
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Pilleux L, Ponticas M, Carrasco C, León A, Salas P, Rodríguez C, Caorsi I. [Invasive hepatosplenic hyalohyphomycosis. Report of a case]. Rev Med Chil 2000; 128:641-6. [PMID: 11016064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Invasive fungal infections are an increasingly common problem in patients with cancer and other vulnerable groups. We report a case of hepatosplenic hialohifomycosis probably by Aspergillus sp. In a patient with acute leukemia, and prolonged neutropenia, treated with corticosteroids and broad spectrum antibiotics. A review concerning diagnosis, clinical course and treatment of this condition is presented.
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Affiliation(s)
- L Pilleux
- Instituto de Hematología, Facultad de Medicina, Universidad Austral de Chile.
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44
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Affiliation(s)
- G. Fetter
- Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Blvd. 14 Sur y Avenida San Claudio, C.P. 72570, Puebla, Pue., Mexico
| | - P. Salas
- Instituto de Física, Universidad Nacional Autónoma de México, A.P.1, C.P. 1010, Querétaro, Qro., Mexico
| | - L. A. Velazquez
- Departamento de Química, Universidad Autónoma Metropolitana−Iztapalapa, Michoacán esq. Purísima, Iztapalapa, C.P. 09340, México, D.F., Mexico
| | - P. Bosch
- Departamento de Química, Universidad Autónoma Metropolitana−Iztapalapa, Michoacán esq. Purísima, Iztapalapa, C.P. 09340, México, D.F., Mexico
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45
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Arraga-Alvarado C, Palmar M, Parra O, Salas P. Fine structural characterisation of a Rickettsia-like organism in human platelets from patients with symptoms of ehrlichiosis. J Med Microbiol 1999; 48:991-997. [PMID: 10535642 DOI: 10.1099/00222615-48-11-991] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Since 1982, Ehrlichia platys infection has been diagnosed in canines from Venezuela by the use of buffy coat smears. In 1992, ehrlichia-like bodies were observed in platelets from a severely ill girl by light microscopy. The patient was seropositive to E. chaffeensis by the indirect fluorescent antibody test (IFAT). Tetracycline was administered and the patient recovered. More than 400 cases with such intra-platelet organisms have been studied at this laboratory over the past 6 years, and all the patients had a good response to the treatment. To determine whether the organisms in human blood platelets were truly platelet ehrlichiae, IFAT and transmission electron microscopy (TEM) studies were undertaken in four patients. Light microscopic examination of blood samples revealed the dense organism inside platelets, and a great reactivity of the blood cells. Sera from the four patients were seronegative against E. chaffeensis and E. platys antigens. Three of four samples contained the intra-platelet organisms when examined by TEM. Electron microscopy showed platelets with vacuoles containing pleomorphic organisms. These organisms had a thickened membrane, an electron-translucent inner area and an electron-dense granular component in the periphery. An abundant electron-dense material was observed surrounding them. The ultrastructure of such micro-organisms has not been reported previously, Based on the similarity of many of their characteristics with rickettsiae, we suggest that the microorganisms found in the present study might belong to the family Rickettsiaceae.
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Affiliation(s)
- Cruz Arraga-Alvarado
- Unidad de Investigaciones Clinicas, Facultad de Ciencias Veterinarias, Universidad del Zulia, Maracaibo
| | - Maria Palmar
- Instituto de Investigaciones Biologicas, Facultad de Medicina, Universidad del Zulia, Maracaibo
| | - Omaira Parra
- Unidad de Investigaciones Clinicas, Facultad de Ciencias Veterinarias, Universidad del Zulia, Maracaibo
| | - Pedro Salas
- Unidad de Microscopia Electronica, Universidad Nacional Experimental Francisco de Miranda, Coro, Venezuela
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46
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47
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Salas P, Hernández J, Montoya J, Navarrete J, Salmones J, Schifter I, Morales J. Effect of tin content on silica mixed oxides: Sulfated and unsulfated catalysts. ACTA ACUST UNITED AC 1997. [DOI: 10.1016/s1381-1169(97)00054-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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48
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Luque E, Peña J, Salas P, Jimena I, Martin JD. Changes in satellite cell population associated with regenerating muscle fibers in rats. J Submicrosc Cytol Pathol 1996; 28:305-11. [PMID: 8765575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Qualitative and quantitative analysis of satellite cells in regenerating muscles was performed at 4, 7 and 30 days after necrosis induced by mepivacaine injection. At 4 days, the small regenerating fibers were accompanied by a high number of satellite cells showing signs of activation; at 7 days, the number of satellite cells decreased and two morphological types of these cells were observed; at 30 days, satellite cells were similar in both number and characteristics to those of the control group. These results would indicate that satellite cells may vary both in number and morphological and morphometric features, according to the degree of maturity of the regenerating muscle fiber.
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Affiliation(s)
- E Luque
- Department of Morphological Sciences (Section of Histology), Faculty of Medicine, University of Córdoba, Spain
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49
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Bartels G, Herrera A, Salas P, Sierra R, Lomonte B. Antibodies to Helicobacter pylori in dyspeptic patients, asymptomatic adults, and children from Costa Rica. APMIS 1995; 103:428-32. [PMID: 7546645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
An enzyme immunoassay for the detection of serum IgG antibodies to H. pylori whole bacterial sonicate was used in a study of dyspeptic adult patients (n = 165), apparently healthy blood donors (n = 154), and children (n = 66) from Costa Rica, where a very high incidence of gastric carcinoma is observed. The mean antibody levels and frequency distributions were similar in the dyspeptic patients and the blood donors. Meanwhile lower antibody levels to H. pylori were more frequently observed in children than in adults, suggesting an age-dependent increase in seroprevalence, as described in studies from other populations.
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Affiliation(s)
- G Bartels
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José
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Toledo JA, Valenzuela MA, Armend�riz H, Aguilar-R�os G, Zapata B, Montoya A, Nava N, Salas P, Schifter I. Oxidative dehydrogenation of 1 -butene to butadiene on ?-Fe2O3/ZnAl2O4 and ZnFexAl2-xO4 catalysts. Catal Letters 1995. [DOI: 10.1007/bf00813694] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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