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Daniels J, Liang L, Benedict KB, Brahney J, Rangel R, Weathers KC, Ponette-González AG. Satellite-based aerosol optical depth estimates over the continental U.S. during the 2020 wildfire season: Roles of smoke and land cover. Sci Total Environ 2024; 921:171122. [PMID: 38395165 DOI: 10.1016/j.scitotenv.2024.171122] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 02/16/2024] [Accepted: 02/18/2024] [Indexed: 02/25/2024]
Abstract
Wildfires produce smoke that can affect an area >1000 times the burn extent, with far-reaching human health, ecologic, and economic impacts. Accurately estimating aerosol load within smoke plumes is therefore crucial for understanding and mitigating these impacts. We evaluated the effectiveness of the latest Collection 6.1 MODIS Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm in estimating aerosol optical depth (AOD) across the U.S. during the historic 2020 wildfire season. We compared satellite-based MAIAC AOD to ground-based AERONET AOD measurements during no-, light-, medium-, and heavy-smoke conditions identified using the Hazard Mapping System Fire and Smoke Product. This smoke product consists of maximum extent smoke polygons digitized by analysts using visible band imagery and classified according to smoke density. We also examined the strength of the correlations between satellite- and ground-based AOD for major land cover types under various smoke density levels. MAIAC performed well in estimating AOD during smoke-affected conditions. Correlations between MAIAC and AERONET AOD were strong for medium- (r = 0.91) and heavy-smoke (r = 0.90) density, and MAIAC estimates of AOD showed little bias relative to ground-based AERONET measurements (normalized mean bias = 3 % for medium, 5 % for heavy smoke). During two high AOD, heavy smoke episodes, MAIAC underestimated ground-based AERONET AOD under mixed aerosol (i.e., smoke and dust; median bias = -0.08) and overestimated AOD under smoke-dominated (median bias = 0.02) aerosol. MAIAC most overestimated ground-based AERONET AOD over barren land (mean NMB = 48 %). Our findings indicate that MODIS MAIAC can provide robust estimates of AOD as smoke density increases in coming years. Increased frequency of mixed aerosol and expansion of developed land could affect the performance of the MAIAC algorithm in the future, however, with implications for evaluating wildfire-associated health and welfare effects and air quality standards.
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Affiliation(s)
- Jacob Daniels
- Department of Electrical Engineering, University of North Texas, 1155 Union Circle #305279, Denton, TX 76203, USA
| | - Lu Liang
- Department of Geography and the Environment, University of North Texas, 1155 Union Circle #305279, Denton, TX 76203, USA
| | - Katherine B Benedict
- Earth and Environmental Science Division, Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, NM 87545, USA
| | - Janice Brahney
- Department of Watershed Sciences and Ecology Center, Utah State University, 5210 Old Main Hill, Logan, UT 84322, USA
| | - Roman Rangel
- Department of Geography and the Environment, University of North Texas, 1155 Union Circle #305279, Denton, TX 76203, USA
| | | | - Alexandra G Ponette-González
- Natural History Museum of Utah, University of Utah, 301 Wakara Way, Salt Lake City, UT 84108, USA; Department of City and Metropolitan Planning, University of Utah, 375 South 1530 East, Suite 220, Salt Lake City, UT 84112, USA.
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Valenzuela-Hernandez G, Berman-Mendoza D, Rangel R, Vazquez J, Bohorquez C, Contreras OE, Carrillo R, García-Gutierrez R, Ramos-Carrazco A. Ammonia thermally treated gallium nitride deposited on gold-nucleation sites. Chem Pap 2022. [DOI: 10.1007/s11696-022-02520-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ramos-Corona A, Rangel R, Espino J, Lara J, Nuñez R, Bartolo-Pérez P, Alvarado-Gil J. High-yield of Lignin degradation under N-ZnO/Graphene oxide compounds. Catal Today 2022. [DOI: 10.1016/j.cattod.2021.04.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Ramos-Corona A, Rangel R, Lara J, Trejo-Tzab R, Bartolo P, Alvarado-Gil JJ. Novel nitrogen plasma doping on CdS/GO compounds and their photocatalytic assessment. Nanotechnology 2021; 33:055705. [PMID: 34678792 DOI: 10.1088/1361-6528/ac328c] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 10/22/2021] [Indexed: 06/13/2023]
Abstract
Nitrogen-doping of cadmium sulfide nanostructured compounds was carried out under a nitrogen plasma source to produce CdS-N compounds. Once prepared, it was supported on graphene oxide sheets for producing CdS-N/GO photocatalysts, which were tested in the degradation of lignin and methylene blue (MB) molecules. Photocatalytic reactions were carried out under UV and visible (vis) energy irradiation. To provide insight on the catalytic behavior the CdS, CdS-N, GO, and CdS-N/GO compounds were characterized using different techniques including x-ray diffraction, scanning electron microscopy, Raman, and UV-vis diffuse reflectance spectroscopy. X-ray photoelectron spectroscopy allowed determining the chemical composition in samples. It was observed an outstanding performance in photocatalytic activity tests, attributed to the extended response towards the visible light regime, and the synergistic effect between CdS-N and GO particles. The catalytic activity tests, reveal that the CdS-N/GO compound achieved over 90% lignin degradation and 100% of MB degradation. In addition, a remarkable performance is observed in the CdS-N/GO compound which exhibited stability after performing several reaction cycles.
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Affiliation(s)
- A Ramos-Corona
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Gral. Francisco J. Múgica S/N, Ciudad Universitaria, Z.P. 58030 Morelia, Michoacán, Mexico
| | - R Rangel
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Gral. Francisco J. Múgica S/N, Ciudad Universitaria, Z.P. 58030 Morelia, Michoacán, Mexico
| | - J Lara
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Gral. Francisco J. Múgica S/N, Ciudad Universitaria, Z.P. 58030 Morelia, Michoacán, Mexico
| | - R Trejo-Tzab
- Facultad de Ingeniería Química, UADY. Mérida, Yucatán, Mexico
| | - P Bartolo
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
| | - J J Alvarado-Gil
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
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Rodríguez-López J, Rangel R, Ramos-Carrazco A, Berman-Mendoza D, Quintana-Owen P, Bartolo-Pérez P, Alvarado-Gil JJ. Columnar nitrogen-doped ZnO nanostructured thin films obtained through atomic layer deposition. Nanotechnology 2021; 32:405704. [PMID: 34186516 DOI: 10.1088/1361-6528/ac0fa1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/29/2021] [Indexed: 06/13/2023]
Abstract
The present study was aimed to develop nitrogen-doped nanostructured ZnO thin films. These films were produced in a sequential procedure involving the atomic layer deposition technique, and a hydrothermal process supported by microwave heating. Employing the atomic layer deposition technique, through self-limited reactions of diethylzinc (DEZn) and H2O, carried out at 3.29 × 10-4atm and 190 °C, a high-quality ZnO seed was grown on a Si (100) substrate, producing a textured film. In a second stage, columnar ZnO nanostructures were grown perpendicularly oriented to the silicon substrate on those films, using a solvothermal process in a microwave heating facility, employing Zn(NO3)2as zinc precursor, while hexamethylenetetramine (HMTA) was used to produce the bridging of Zn2+ions. The consequence of N-doping concentration on the physicochemical properties of ZnO thin films was studied. The manufactured films were structurally analyzed by scanning electron microscopy and x-ray diffraction. Also, x-ray photoelectron spectroscopy, Raman, and UV-vis spectroscopies were used to provide further insight on the effect of nitrogen doping. The N-doped films displayed textured wurtzite-like structures that changes their preferential growth from the (002) to the (100) crystallographic plane, apparently promoted by the increase of nitrogen precursor. It is also shown that nitrogen-doped films undergo a reduction in their bandgap, compared to ZnO. The methodology presented here provides a viable way to perform high-quality N-ZnO nanostructured thin films.
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Affiliation(s)
- J Rodríguez-López
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicólas de Hidalgo, Morelia, Michoacán, Mexico
| | - R Rangel
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicólas de Hidalgo, Morelia, Michoacán, Mexico
| | - A Ramos-Carrazco
- Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora, Mexico
| | - D Berman-Mendoza
- Departamento de Investigación en Física, Universidad de Sonora, Hermosillo, Sonora, Mexico
| | - P Quintana-Owen
- Departamento de Física Aplicada, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Mérida, Yucatán, Mexico
| | - P Bartolo-Pérez
- Departamento de Física Aplicada, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Mérida, Yucatán, Mexico
| | - J J Alvarado-Gil
- Departamento de Física Aplicada, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Mérida, Yucatán, Mexico
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Cervantes-López JL, Rangel R, Meneses-Rodríguez D, Rodríguez-Gattorno G, Alvarado-Gil JJ. Ce, Eu incorporation through doping of ALD-ZnO thin films for enhancing their photoluminescent properties. Nanotechnology 2021; 32:145601. [PMID: 33352537 DOI: 10.1088/1361-6528/abd5ea] [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] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Nanostructured ZnO nanoarrays deposited on silicon oriented substrates is a very promising area in the study of the control of physicochemical properties, in which photoluminescence plays a crucial role. This optical property inherent to ZnO, can be favorably modified through the inclusion of doping elements, with the purpose of appropriately modifying their optical absorption and luminescence. Following this objective, in the present work we present the development of Zn(1-x-y)Ce(x)Eu(y)O nanostructured thin films. The samples were produced in two steps process by atomic layer deposition technique followed by a solvothermal synthesis. The purpose of Cerium and Europium incorporation into the ZnO compound is to enhance the photoluminescence in ZnO thin films. In a first stage textured thin films were obtained from diethylzinc at a temperature of 190 °C and a pressure of 3.29 × 10-4 atm, on silicon substrates (111). Subsequently, the perpendicular growth of nanostructures was induced under a solvothermal process, where Zn(NO3)2 was used as Zn precursor and hexamethylene-tetramine operating as a dual-ligand to promote the linking of Zn2+ ions. The growth of cerium-europium ZnO nanostructures was promoted with Ce(C2H3O2)3·H2O and Eu(NO3)3·5H2O. The obtained Zn(1-x-y)Ce(x)Eu(y)O nanostructured thin films, were examined through SEM-microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and photoluminescence studies. The attained results show that it is feasible to produce Ce-Eu-doped ZnO nanostructures with tailored photoluminescence and crystal size. Interestingly the Ce-Eu doping induces a strong shift in comparison to the typical UV emission of ZnO; an effect that can be related with the increase of lattice defects in ZnO.
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Affiliation(s)
- J L Cervantes-López
- División de estudios de Posgrado, Facultad de Ingeniería Química, Universidad Michoacana de S.N.H., Morelia, Mexico
- Departamento de Física Aplicada, CINVESTAV-IPN, Unidad Mérida, Mérida, Yucatán, Mexico
| | - R Rangel
- División de estudios de Posgrado, Facultad de Ingeniería Química, Universidad Michoacana de S.N.H., Morelia, Mexico
| | - D Meneses-Rodríguez
- Departamento de Física Aplicada, CINVESTAV-IPN, Unidad Mérida, Mérida, Yucatán, Mexico
| | - G Rodríguez-Gattorno
- Departamento de Física Aplicada, CINVESTAV-IPN, Unidad Mérida, Mérida, Yucatán, Mexico
| | - J J Alvarado-Gil
- Departamento de Física Aplicada, CINVESTAV-IPN, Unidad Mérida, Mérida, Yucatán, Mexico
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Gonzalez-A E, Rangel R, Solís-Garcia A, Venezia A, Zepeda T. FTIR investigation under reaction conditions during CO oxidation over Ru(x)-CeO2 catalysts. Molecular Catalysis 2020. [DOI: 10.1016/j.mcat.2020.111086] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ramos-Corona A, Rangel R, Alvarado-Gil JJ, Bartolo-Pérez P, Quintana P, Rodríguez-Gattorno G. Photocatalytic performance of nitrogen doped ZnO structures supported on graphene oxide for MB degradation. Chemosphere 2019; 236:124368. [PMID: 31323553 DOI: 10.1016/j.chemosphere.2019.124368] [Citation(s) in RCA: 10] [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: 03/12/2019] [Revised: 07/06/2019] [Accepted: 07/13/2019] [Indexed: 06/10/2023]
Abstract
In the present work, the photocatalytic efficiency of a novel system based on ZnO doped with nitrogen (ZT) and supported on graphene oxide (GO) is investigated. ZnO synthesis and their N doping were carried out in a microwave reactor using thiourea as nitrogen source, while the GO was prepared through a variation of the Hummers' method. Structural, morphological and photochemical characterization of the developed material was performed by X-ray diffraction (XRD), UV-Vis spectroscopy, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), analysis by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The compounds were used to photodegrade the methylene blue molecule, which confirms the efficiency of nitrogen doped supported system compared to pristine ZnO. The degradation percentage of MB under UV energy using nitrogen-doped ZnO/GO, in a time of 35 min, reached 98% degradation; while using visible light 93% of degradation was reached.
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Affiliation(s)
- A Ramos-Corona
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Z.P. 58030, Morelia, Michoacán, Mexico
| | - R Rangel
- División de Estudios de Posgrado de la Facultad de Ingeniería Química, Universidad Michoacana de San Nicolás de Hidalgo, Z.P. 58030, Morelia, Michoacán, Mexico.
| | - J J Alvarado-Gil
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
| | - P Bartolo-Pérez
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
| | - P Quintana
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
| | - G Rodríguez-Gattorno
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional-Unidad Mérida, Z.P. 97310, Mérida, Yucatán, Mexico
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Leal B, Carvalho C, Chaves J, Bettencourt A, Ferreira R, Rangel R, Santos A, Boleixa D, Freitas J, Lopes J, Ramalheira J, Martins da Silva B, Costa P, Martins da Silva A, Correia-de-Sá P. Inverse correlation between miR-22 serum levels and p2x7r-mediated inflammatory response in mesial temporal lobe epilepsy patients. J Neurol Sci 2017. [DOI: 10.1016/j.jns.2017.08.295] [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: 11/16/2022]
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Seminoff JA, Eguchi T, Carretta J, Allen CD, Prosperi D, Rangel R, Gilpatrick JW, Forney K, Peckham SH. Loggerhead sea turtle abundance at a foraging hotspot in the eastern Pacific Ocean: implications for at-sea conservation. ENDANGER SPECIES RES 2014. [DOI: 10.3354/esr00601] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Rangel R, Maya-Yescas R, García R. Novel [Ce1−xLaxO2, La2−yCeyO3]/Bi2Mo0.9W0.1O6 catalysts for CO oxidation at low temperature. Catal Sci Technol 2012. [DOI: 10.1039/c2cy00368f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Rangel R, Bartolo-Pérez P, Martínez E, Trejo-Cruz XA, Díaz G, Galván DH. Catalytic activity and X-ray photoelectron spectroscopy performance of Bi2MoxW(1−x)O6 solid-solutions. Catal Sci Technol 2012. [DOI: 10.1039/c2cy00506a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Flores MS, Tamez-Treviño E, Castañeda F, Tijerina-Menchaca R, Galan-Wong L, Rangel R. Preparation ofEntamoeba histolyticaantigens without enzymatic inhibitors. Parasitology 2005; 131:231-6. [PMID: 16145939 DOI: 10.1017/s0031182005007730] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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: 11/06/2022]
Abstract
The goal of this work is to report a novel assay that preserves antigenicity of extracts with high protease content without using enzymatic inhibitors. A great reduction of proteolytic activity in the insoluble chloroform/methanol and heated amoebic fraction (IC[ratio ]MC) was obtained by this method, even in the presence of sodium dodecyl sulphate and 2-mercaptoethanol. The substrates azo-casein and the hide powder azure were used to determine the reduction of proteolytic activity of IC[ratio ]MC compared with the activity of crude extract and crude extract with iodoacetamide. The IC[ratio ]MC SDS-PAGE pattern shows a higher quantity of bands than extract with the inhibitor iodoacetamide or than crude extract. In addition, anti-Entamoeba histolyticaantibodies from amoebic liver abscess patients recognized a richer antigenic Western blot pattern in the IC[ratio ]MC fraction than in crude extract alone or with inhibitor. The described method has proved to be suitable to preserve amoebic antigens for its use in diagnostic tests and it can be used for immunological response studies againstE. histolyticaantigens. Furthermore we propose that this method to obtain the IC[ratio ]MC fraction can be applied for the study of other microorganisms or cells with high enzymatic content.
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Affiliation(s)
- M S Flores
- Departamento de Microbiologia, Facultad de Medicina, UANL Apdo. Postal 4355-H, Monterrey N.L. C.P. 64000, Mexico.
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Siddiqa A, Sims-Mourtada JC, Guzman-Rojas L, Rangel R, Guret C, Madrid-Marina V, Sun Y, Martinez-Valdez H. Regulation of CD40 and CD40 ligand by the AT-hook transcription factor AKNA. Nature 2001; 410:383-7. [PMID: 11268217 DOI: 10.1038/35066602] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [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: 11/08/2022]
Abstract
Proteins containing AT hooks bind A/T-rich DNA through a nine-amino-acid motif and are thought to co-regulate transcription by modifying the architecture of DNA, thereby enhancing the accessibility of promoters to transcription factors. Here we describe AKNA, a human AT-hook protein that directly binds the A/T-rich regulatory elements of the promoters of CD40 and CD40 ligand (CD40L) and coordinately regulates their expression. Consistent with its function, AKNA is a nuclear protein that contains multiple PEST protein-cleavage motifs, which are common in regulatory proteins with high turnover rates. AKNA is mainly expressed by B and T lymphocytes, natural killer cells and dendritic cells. During B-lymphocyte differentiation, AKNA is mainly expressed by germinal centre B lymphocytes, a stage in which receptor and ligand interactions are crucial for B-lymphocyte maturation. Our findings show that an AT-hook molecule can coordinately regulate the expression of a key receptor and its ligand, and point towards a molecular mechanism that explains homotypic cell interactions.
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Affiliation(s)
- A Siddiqa
- Department of Immunology, Box 178, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030, USA
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Abreu T, Plaisance K, Rexroad V, Nogueira S, Oliveira RH, Evangelista LA, Rangel R, Silva IS, Knupp C, Lambert JS. Bioavailability of once- and twice-daily regimens of didanosine in human immunodeficiency virus-infected children. Antimicrob Agents Chemother 2000; 44:1375-6. [PMID: 10770783 PMCID: PMC89876 DOI: 10.1128/aac.44.5.1375-1376.2000] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [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: 11/20/2022] Open
Abstract
The bioavailability of didanosine at 180 mg/m(2) once daily was compared to that at 90 mg/m(2) twice daily in 24 children with advanced human immunodeficiency virus infection. Children were studied at steady state using optimal sampling and prior pharmacokinetic parameter estimates. Relative bioavailability was 0. 95 +/- 0.49, supporting the potential clinical adequacy of once-daily dosing.
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Affiliation(s)
- T Abreu
- Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Abstract
BACKGROUND Psychosocial factors have been considered important in the initiation of drug abuse and seem to affect its clinical course and outcome. Several studies have reported psychopathology, namely depression, to be consistently high in addiction. The aim of this investigation was to evaluate the prevalence of depression and its relationship to the severity of drug abuse in a Portuguese sample of drug addicts. METHODS Two hundred and eighty-five drug addicts (23 women and 262 men, aged between 16 and 41 years old), diagnosed according to the DSM-IV criteria, were contacted during their first visit for treatment at public health centres. Social, demographic and behavioural characteristics of the study sample were obtained by interview using a structured questionnaire. The severity of drug abuse was evaluated using a Portuguese version of the Drug Abuse Screening Test, and depression was assessed by the Zung self-rating depression scale. RESULTS The prevalence of depression was 51.2% and was higher in females than males (77.8 vs. 48.7%, p = 0.034). A significant correlation was also found between the severity of drug abuse and depression scores, which was also stronger in females (r = 0.53 vs. r = 0.24). CONCLUSIONS This study showed a high prevalence of depression in drug addicts, regardless of the type and duration of drug abuse, and a significant association between depression and severity of drug addiction.
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Affiliation(s)
- R Coelho
- Department of Psychiatry, University of Porto Medical School, Porto, Portugal.
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Guzman-Rojas L, Sims JC, Rangel R, Guret C, Sun Y, Alcocer JM, Martinez-Valdez H. PRELI, the human homologue of the avian px19, is expressed by germinal center B lymphocytes. Int Immunol 2000; 12:607-12. [PMID: 10784606 DOI: 10.1093/intimm/12.5.607] [Citation(s) in RCA: 22] [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: 11/14/2022] Open
Abstract
We report the identification of a human cDNA encoding a 25 kDa protein of relevant evolutionary and lymphoid interest (PRELI). PRELI was cloned by screening a B lymphocyte-specific cDNA library with a probe generated by mRNA differential display. PRELI amino acid sequence is 85% similar to the avian px19 protein, expressed within the blood islands and in the liver during avian embryo development. PRELI and px19 contain tandem repeats (A/TAEKAK) of the late embryogenesis abundant (LEA) motif, characteristic of a group of survival molecules and originally thought to be present only in plant proteins. Interestingly, PRELI expression is high in the fetal liver, a major site for B cell lymphopoiesis, while the mRNA levels in other fetal tissues such as the brain, lung, and kidney are comparatively low. At the adult stage, PRELI expression is drastically reduced in the liver but exhibits high mRNA levels in the spleen, brain, lung and kidney tissues, suggesting that PRELI expression may be important for the development of vital and immunocompetent organs. Moreover, PRELI is also highly expressed in the adult lymph nodes and peripheral blood leukocytes, further stressing that at the adult stage, PRELI expression may be important during secondary immune responses. Consistent with this hypothesis, the expression of PRELI is predominant within germinal centers (GC), a stage in which B lymphocytes are under a stressful selection pressure. Taken together these data: (i) strongly support the notion that the conserved LEA motif represents a phylogenetic link between plants and animals, (ii) reveal a novel molecule whose expression may play a role in the maturation of distinct human tissues, and (iii) suggest that PRELI expression may be important for GC B lymphocytes.
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Affiliation(s)
- L Guzman-Rojas
- Department of Immunology, Box 178, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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Reis JL, Vasconcelos C, Rangel R, Xavier J, Barroso C, Melo-Pires M, Carvalho E. [Dysembryoplastic neuroepithelial tumors]. Rev Neurol 2000; 30:436-41. [PMID: 10775970] [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: 02/16/2023]
Abstract
INTRODUCTION The dysembryoplastic neuroepithelial tumors tend to occur in young patients, with partial complex partial seizures which is refractory to medical treatment. These are stable lesions, with defined histological features, specially with clinical data corroboration. CLINICAL CASES The clinical, imagiological, operative, and histopathological data of six patients with proved dysembryoplastic neuroepithelial tumors were reviewed. All patients had seizures with age at onset ranged from 7 to 27 years. Five lesions were located in the temporal lobe and one in the parietal lobe. Common features included cortical to subcortical location, low density in CT-scan, very low signal intensity on T1-weighted images and high signal on T2-weighted images. Calcification occurred in two lesions, and three showed contrast enhancement. Complete resection of the tumor was performed in three cases, and subtotal resection in other three cases. Pathological features included oligodendroglial-like cells, glioneural component, and few cases showed dysplastic cortical disorganization. The postoperative period of follow-up ranged from 2 to 18 months. Four patients were seizure free, two of which had subtotal resection of the lesion. The remaining two patients maintained seizures. CONCLUSIONS The clinical, imagiological and histopathological data of the six cases presented are generally compatible with those of the reports reviewed by the authors. The imagiological features are nonspecific. Surgical treatment permits histological diagnosis and epilepsy control.
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Affiliation(s)
- J L Reis
- Servicio de Neurocirugía, Hospital Geral Santo António, Porto, Portugal.
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da Costa JP, de Sousa MJ, Magalhaes T, Ribeiro C, Grams AC, Ramon J, Rangel R. Assessment of drug addiction. The experience of the Medico Legal Institute of Oporto. Med Law 2000; 19:309-319. [PMID: 10994216] [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: 05/23/2023]
Abstract
Since 1993 in Portugal, it is possible, by legal enforcement, to request forensic examination to study possible conditions of drug addiction. On the basis of examinations carried out in the Medico Legal Institute of Oporto, we present a study of 494 cases involving the relation to the demographic data of the examined individuals, their family background, legal situation, age at which drug consumption began, consumption profile at the beginning and at time of forensic examination and our conclusions.
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Abstract
OBJECTIVE The study reports the cost-effectiveness results of end-stage renal disease (ESDR) patients in Mexico in terms of years of life gained and quality of life and the economic cost with regards to three treatment alternatives that could be considered mutually exclusive: continuous peritoneal ambulatory dialysis (CAPD), hemodialysis (HD) and renal transplant (RT). METHOD The economic costs were calculated by using the average cost case-management methodology and further, the probable of life expectancy and the quality of life were cross-sectionally assessed by means of the Quality Adjusted Life Years (QALY) measured by the Rosser Index. RESULTS The results show that economic costs in US$ of the three treatment alternatives were: CAPD $5,643.07, HD $9,631.60, and RT $3,021.63. The probability of life expectancy for CAPD and RT for the first and third year were: 86.2% and 66.9%, and 89.9% and 79.6%, respectively. The QALY scores for patients were: CAPD 0.8794, HD 0.8640, and RT 0.9783. CONCLUSION The intervention with the highest cost-effectiveness coefficient was the renal transplant (3,088.69), followed by the CAPD (6,416.95) and HD (11,147.68). A significant difference was found between the transplanted patients and patients undergoing dialysis. Finally, this study concluded that the RT offers the least expensive alternative and the greatest number of years of life gained as well as providing significant changes in the quality of life of ESRD patients.
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Affiliation(s)
- A Arredondo
- Departamento de Investigación en Costos y Financiamiento para la Salud, Instituto Nacional de Salud Pública, Cuernavaca Morelos, México.
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Galván DH, Rangel R, Alonso G. Experimental and Theoretical Studies of Microstructural Instabilities in WS2Undergoing Electron Irradiation. ACTA ACUST UNITED AC 1998. [DOI: 10.1080/10641229809350253] [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: 10/22/2022]
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Affiliation(s)
- R Rangel
- University of Zulia School of Medicine, Maracaibo, Venezuela
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Abstract
INTRODUCTION The results of a study which identified the cost of health interventions in the management of patients with chronic renal disease are presented. MATERIAL AND METHOD The costing method was based on a consensus technique and the instrumentation of case management through the identification of the materials used and functions of production for the demand of each service solicited. The interventions included: peritoneal dialysis, hemodialysis, and renal transplant. RESULTS The cost per event in U.S. dollars was $3.71, $57.95, and $8,778.32, respectively. The annual cost of case management was: Peritoneal Dialysis $5,643.07, Hemodialysis $9,631.60 and renal transplant $3,021.67. CONCLUSIONS The information generated from the costs of the events differed considerably from the information that was generated by the annual cost of case management. These differences are significant for the design and evaluation of patterns for allocating resources.
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Affiliation(s)
- A Arredondo
- Departamento de Investigación en Costos y Financiamiento para la Salud, Instituto Nacional de Salud Pública, Morelos, México
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Medina E, Kardar M, Rangel R. Magnetoconductance anisotropy and interference effects in variable-range hopping. Phys Rev B Condens Matter 1996; 53:7663-7672. [PMID: 9982210 DOI: 10.1103/physrevb.53.7663] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Poss JE, Rangel R. Working effectively with interpreters in the primary care setting. Nurse Pract 1995; 20:43-47. [PMID: 8610033] [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: 05/22/2023]
Abstract
Because of immigration to the United States, the number of persons who speak languages other than English has grown over the past several decades. In addition, many groups whose primary language is not English are exhibiting rapid population growth rates. As a result, health care providers may find they require an interpreter to communicate with patients. Guidelines are presented to facilitate the effective choice and utilization of interpreters in primary care. Suggestions are also presented to help interpreters work effectively in the health care setting.
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Affiliation(s)
- J E Poss
- Daemen College, Buffalo, NY, USA
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Renthal R, McMillan K, Guerra L, Garcia MN, Rangel R, Jen CM. Long-range effects on the retinal chromophore of bacteriorhodopsin caused by surface carboxyl group modification. Biochemistry 1995; 34:7869-78. [PMID: 7794898 DOI: 10.1021/bi00024a011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 01/27/2023]
Abstract
Carboxyl groups of bacteriorhodopsin (bR) that are modified by 1-ethyl-3-[3-(trimethylamino)-propyl]carbodiimide (ETC) have been identified. Reaction of deionized purple membrane with a 400-fold molar excess of ETC or [14C]ETC for 1 h at 0 degree C incorporates about 3.5 mol of ETC/mol of bR. Proteinase K cleavage of ETC-modified bacterioopsin (bO) produced small 14C-labeled peptides. Amino acid sequence analysis showed three major ETC-modified residues: Glu 234, Asp 38, and Glu 74. Proteolysis of purple membrane with papain removes the ETC site at Glu 234. Treatment of ETC-modified, papain-cleaved purple membrane with hydroxylamine removes half of the remaining ETC label. Subsequent cleavage with chymotrypsin, followed by amino acid sequence analysis, revealed that most of the remaining label was at Glu 74. bR modified by ETC primarily at Glu 74 displays two alterations in the retinal chromophore, located in the membrane interior at a distance more than 2 nm away from the modified carboxyl group. (1) The acid-induced purple-to-blue transition undergoes a shift in apparent pK from 3.2 to 2.3. (2) The second-order rate constant for chromophore regeneration from bO and retinal is diminished from 3600 to 1700 M-1 s-1 in membrane sheets. Most of the shift in the pK of the purple-to-blue transition can be explained by the quaternary ammonium ion of ETC attached to Glu 74 overlapping the postulated location of the guanidinium group of Arg 82.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R Renthal
- Division of Earth and Physical Sciences, University of Texas at San Antonio 78249, USA
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Rangel R, Rocha L, Ramirez JL, Ibarra MJ, Solorza G, Monroy A, Ramirez MA, Herrera A, Weiss-Steider B. Generation of memory CD4+, CD8+, CD45RO+ and CD16- lymphocytes activated with IL-2, INF-gamma, and TNF-alpha with specific cytotoxicity against autologous cervical cancer cells in a mixed leukocyte-tumour cell culture. Eur Cytokine Netw 1995; 6:195-202. [PMID: 8589277] [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: 01/31/2023]
Abstract
Cytotoxic T lymphocytes (CTL) specific against autologous human cervical cancer cells were generated in vitro from peripheral blood leukocytes (PBL) from four patients with non-keratinized epidermoid carcinoma. For this purpose, these patients' PBL were co-cultured for 28 days either with IL-2 or a mixture of IL-2, IFN-gamma and TNF-alpha in the presence of autologous tumour cells (ATC). Our results showed that these CTL were highly cytotoxic for ATC, weakly cytotoxic for heterologous cervical cancer tumour cells, and not cytotoxic for carcinoma cell lines, normal cervix cells nor autologous PBL. Proliferation and cytotoxicity against ATC were greater when the PBL were activated with the three cytokines. These CTL had a CD4:CD8 ratio of 1:1, were CD16- and CD45RO+ and their killing activity was inhibited by antibodies against CD3, CD8 and MHC-class I but not by antibodies against CD4, CD16 or HLA-class II. The possibility of generating specific CTL in long term cultures for cervical cancer therapy is also discussed.
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MESH Headings
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Autoimmunity
- CD4 Antigens/analysis
- CD8 Antigens/analysis
- CD8 Antigens/immunology
- Carcinoma, Squamous Cell/immunology
- Carcinoma, Squamous Cell/pathology
- Cervix Uteri/immunology
- Cytotoxicity, Immunologic
- Female
- HLA Antigens/analysis
- HLA Antigens/immunology
- HLA-D Antigens/analysis
- HLA-D Antigens/immunology
- Humans
- Immunologic Memory/drug effects
- Interferon-gamma/pharmacology
- Interleukin-2/pharmacology
- Laryngeal Neoplasms/pathology
- Leukocyte Common Antigens/analysis
- Leukocytes, Mononuclear/immunology
- Lymphocyte Activation/drug effects
- Lymphocyte Culture Test, Mixed
- Lymphocyte Subsets/chemistry
- Lymphocyte Subsets/drug effects
- Muromonab-CD3/pharmacology
- Receptors, IgG/analysis
- Receptors, IgG/immunology
- Recombinant Proteins
- T-Lymphocytes, Cytotoxic/chemistry
- T-Lymphocytes, Cytotoxic/drug effects
- Tumor Cells, Cultured
- Tumor Necrosis Factor-alpha/pharmacology
- Uterine Cervical Neoplasms/immunology
- Uterine Cervical Neoplasms/pathology
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Affiliation(s)
- R Rangel
- Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autonoma de Mexico, Mexico D.F
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Lin JC, Taylor PL, Rangel R. Ferromagnetic phase transition in random Potts spin chains. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1993; 47:981-985. [PMID: 9960095 DOI: 10.1103/physreve.47.981] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Fernández JF, Rangel R, Rivero J. Crossover length from invasion percolation to diffusion-limited aggregation in porous media. Phys Rev Lett 1991; 67:2958-2961. [PMID: 10044602 DOI: 10.1103/physrevlett.67.2958] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Rangel R, Guerrero LE. Multifractality, multifractal phase transitions, and symmetry-increasing bifurcations in ac-driven phase-slip centers. Phys Rev A 1991; 43:669-680. [PMID: 9905084 DOI: 10.1103/physreva.43.669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Oyen O, Tsay T, Rangel R. [Facial symmetry and functional symmetry (3)]. Pract Odontol 1990; 11:11-3, 15-7. [PMID: 2132260] [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: 12/30/2022]
Abstract
The literature abounds in analyses of the causes, diagnosis and treatment schemes for handling dental-facial asymmetries. In the course of time, however, our understanding of the subject has improved considerably, thanks to efforts and findings contributed by different researchers.
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Affiliation(s)
- O Oyen
- Case Western Reserve University, Cleveland, Ohio 44106
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Abstract
Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.
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Affiliation(s)
- B J Wilder
- Neurology Service, Veterans Administration Medical Center, Gainesville, FL 32602
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Abstract
Clinical and computerized tomography findings in patients with miliary infestation of cysticerci in brain parenchyma are presented. Cysticercotic encephalitis produces a severe and frequently fatal neurological disorder. Although parenchymal cysticercosis is common in endemic areas, in the cases reported here, the pathology is induced by a severe inflammatory response in brain parenchyma rather than by the physical presence of multiple cysts. As a result of diffuse brain edema, all cases develop subacute severe intracranial hypertension and compromise of visual function. One important feature of this form of neurocysticercosis is that it particularly affects young women.
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Hartung GH, Rangel R. Exercise training in post-myocardial infarction patients: comparison of results with high risk coronary and post-bypass patients. Arch Phys Med Rehabil 1981; 62:147-50. [PMID: 6972205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Measurements were made before and following 3 to 6 months of exercise therapy in 24 patients who had had myocardial infarction (group MI), in 16 patients having positive test and/or multiple risk factors for coronary heart disease (Group CHD), and in 10 patients who had undergone coronary artery bypass surgery (Group CAB). All patients were men and had a mean age of 51.6 years. Exercise training was conducted 3 times per week for a duration of 20 to 40 minutes per session. Walking and jogging both on a treadmill and a track and stationary cycling were used as training modalities. A paired t test was used to determine significance of differences between pre- and post-treatment results for each group. Percent body fat decreased in each group and aerobic capacity increased significantly (p less than 0.01) in all 3 groups (6.2 ml/kg . min-1 in MI, 7.0 ml/kg . min-1) in CHD, and 8.0 ml/kg . min-1 in CAB). Changes in other exercise related variables were found not to be statistically significant. Analysis of variance yielded no difference among the 3 groups for any of the variables evaluated. The results clearly indicate that the trainability of the MI patient is equivalent to that of the cardiac patient who has not suffered an infarct and to that of the post-CAB patient.
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Beaudry PH, Marks MI, McDougall D, Desmond K, Rangel R. Is anti-Pseudomonas therapy warranted in acute respiratory exacerbations in children with cystic fibrosis? J Pediatr 1980; 97:144-7. [PMID: 7381634 DOI: 10.1016/s0022-3476(80)80155-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A controlled study was designed to clarify the indications for antibiotic therapy in children with advanced cystic fibrosis hospitalized with respiratory exacerbations. Twenty-two children with severe CF and signs of acute lower respiratory infection were randomly assigned to receive either cloxacillin or carbenicillin plus gentamicin administered intravenously for ten days. Other aspects of therapy were constant. The groups were comparable in all respects and Pseudomonas aeruginosa was the predominant sputum pathogen in most patients. Clinical improvement, chest radiograph changes, evidence of airway obstruction, and bacteriologic flora of sputum were no different regardless of the regimen used. These results suggest that the use of anti-Pseudomonas medication in these children may not always be necessary. These observations need to be confirmed by blind-controlled studies in larger numbers of patients with mild as well as severe respiratory involvement.
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Hartung GH, Smolensky MH, Harrist RB, Rangel R, Skrovan C. Effects of varied durations of training on improvement in cardiorespiratory endurance. J Hum Ergol (Tokyo) 1977; 6:61-8. [PMID: 608958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Twenty-nine subjects trained for 6 weeks for the purpose of comparing the effects of various durations of exercise. All subjects trained three days per week at 75% of maximum heart rate. Training durations were 5 min (N = 10), 15 min (N = 10) and 25 min (N = 9) with over 80% of the training sessions consisting of monitored treadmill walking on a grade. Pre and post-testing consisted of a maximal treadmill walk and a submaximal bicycle ride for the three training groups and a control group (N = 10). The improvements in treadmill time were 7.7%, 14.7% and 20.2% for the three training groups, all significant. The improvement for the 5 min group was not different than that of the control or 15 min groups. Improvement in the 25 min group was significantly greater than the control and 5 min groups, but not the 15 min group. The same differences were noted when estimated maximal oxygen uptake changes were analyzed. The results indicate that at least 15 and preferably 25 min of exercise is necessary to produce optimal endurance improvement with the training intensity and frequency used in this study.
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