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Pérez-Torres A, Hernández-Barreto DF, Bernal V, Giraldo L, Moreno-Piraján JC, da Silva EA, Alves MDCM, Morais J, Hernandez Y, Cortés MT, Macías MA. Sulfur-Doped g-C 3N 4 Heterojunctions for Efficient Visible Light Degradation of Methylene Blue. ACS Omega 2023; 8:47821-47834. [PMID: 38144128 PMCID: PMC10734029 DOI: 10.1021/acsomega.3c06320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 10/25/2023] [Accepted: 11/20/2023] [Indexed: 12/26/2023]
Abstract
The discharge of synthetic dyes from different industrial sources has become a global issue of concern. Enormous amounts are released into wastewater each year, causing concerns due to the high toxic consequences. Photocatalytic semiconductors appear as a green and sustainable form of remediation. Among them, graphitic carbon nitride (g-C3N4) has been widely studied due to its low cost and ease of fabrication. In this work, the synthesis, characterization, and photocatalytic study over methylene blue of undoped, B/S-doped, and exfoliated heterojunctions of g-C3N4 are presented. The evaluation of the photocatalytic performance showed that exfoliated undoped/S-doped heterojunctions with 25, 50, and 75 mass % of S-doped (g-C3N4) present enhanced activity with an apparent reaction rate constant (kapp) of 1.92 × 10-2 min-1 for the 75% sample. These results are supported by photoluminescence (PL) experiments showing that this heterojunction presents the less probable electron-hole recombination. UV-vis diffuse reflectance and valence band-X-ray photoelectron spectroscopy (VB-XPS) allowed the calculation of the band-gap and the valence band positions, suggesting a band structure diagram describing a type I heterojunction. The photocatalytic activities calculated demonstrate that this property is related to the surface area and porosity of the samples, the semiconductor nature of the g-C3N4 structure, and, in this case, the heterojunction that modifies the band structure. These results are of great importance considering that scarce reports are found concerning exfoliated B/S-doped heterojunctions.
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Affiliation(s)
- Andrés
F. Pérez-Torres
- Crystallography
and Chemistry of Materials, CrisQuimMat, Department of Chemistry, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - Diego F. Hernández-Barreto
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Valentina Bernal
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Liliana Giraldo
- Facultad
de Ciencias, Departamento de Química, Grupo de Calorimetría, Universidad Nacional de Colombia, Sede Bogotá 01, Bogotá D.C. 111321, Colombia
| | - Juan Carlos Moreno-Piraján
- Facultad
de Ciencias, Departamento de Química, Grupo de Investigación
en Sólidos Porosos y Calorimetría, Universidad de los Andes, Bogotá
D.C. 111711, Colombia
| | - Edjan Alves da Silva
- Electron
Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Maria do Carmo Martins Alves
- Instituto
de Química, Universidade Federal
do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Jonder Morais
- Electron
Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS, Brazil
| | - Yenny Hernandez
- Department
of Physics, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - María T. Cortés
- Departamento
de Química, Universidad de los Andes, Bogotá D.C. 111711, Colombia
| | - Mario A. Macías
- Crystallography
and Chemistry of Materials, CrisQuimMat, Department of Chemistry, Universidad de los Andes, Bogotá D.C. 111711, Colombia
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2
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Martínez-Tapia R, Estrada-Rojo F, López-Aceves T, García-Velasco S, Rodríguez-Mata V, Pulido-Camarillo E, Pérez-Torres A, López-Flores E, Ugalde-Muñiz P, Noriega-Navarro R, Navarro L. A model of traumatic brain injury in rats is influenced by neuroprotection of diurnal variation which improves motor behavior and histopathology in white matter myelin. Heliyon 2023; 9:e16088. [PMID: 37215868 PMCID: PMC10196591 DOI: 10.1016/j.heliyon.2023.e16088] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 04/07/2023] [Accepted: 05/04/2023] [Indexed: 05/24/2023] Open
Abstract
Traumatic brain injury (TBI) represents a significant public health concern and has been associated with high rates of morbidity and mortality. TBI generates two types of brain damage: primary and secondary. Secondary damage originates a series of pathophysiological processes, which include metabolic crisis, excitotoxicity, and neuroinflammation, which have deleterious consequences for neuronal function. However, neuroprotective mechanisms are also activated. The balance among these tissue responses, and its variations throughout the day determines the fate of the damage tissue. We have demonstrated less behavioral and morphological damage when a rat model of TBI was induced during the light hours of the day. Moreover, here we show that rats subjected to TBI in the dark lost less body weight than those subjected to TBI in the light, despite no change in food intake. Besides, the rats subjected to TBI in the dark had better performance in the beam walking test and presented less histological damage in the corpus callosum and the cingulum bundle, as shown by the Klüver-Barrera staining. Our results suggest that the time of day when the injury occurs is important. Thus, this data should be used to evaluate the pathophysiological processes of TBI events and develop better therapies.
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Affiliation(s)
- R.J. Martínez-Tapia
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
| | - F. Estrada-Rojo
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
| | - T.G. López-Aceves
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
- Programa Regional de Posgrado en Biotecnología, Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Sinaloa, Culiacán, Sinaloa, Mexico
| | - S. García-Velasco
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
| | - V. Rodríguez-Mata
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - E. Pulido-Camarillo
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - A. Pérez-Torres
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - E.Y. López-Flores
- Residente de Anatomía Patológica, CMN “20 de Noviembre”, ISSSTE, Ciudad de México, Mexico
| | - P. Ugalde-Muñiz
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
| | - R. Noriega-Navarro
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
| | - L. Navarro
- Laboratory of Neuroendocrinology, Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, Mexico
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Pérez-Torres A, González-Hernández M, Ortiz P, Cortés MT. Statistical Study of the Influence of Electrosynthesis Conditions on the Capacitance of Polypyrrole. ACS Omega 2022; 7:15580-15595. [PMID: 35571838 PMCID: PMC9096924 DOI: 10.1021/acsomega.1c06843] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/05/2022] [Indexed: 06/15/2023]
Abstract
Polypyrrole (PPy) is a promising material for the fabrication of flexible energy storage devices and much research has been published. However, no statistical tools have been used to relate PPy synthesis conditions to its energy storage performance, considering not only the main synthesis factors but also their interactions. In this work, we use a factorial design of experiments to evaluate the influence of two electropolymerization methods and three synthesis parameters on the energy storage capacity of PPy coatings. The polymers were characterized by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), electrochemical impedance spectroscopy (EIS), Raman spectroscopy, and scanning electron microscopy (SEM). Statistical tests showed that ClO4 --doped PPy exhibits higher capacitances than p-toluenesulfonate (pTS)-doped PPy, with a maximum capacitance of 353.75 ± 1.6 F g-1 at 1 A g-1. However, the pTS-doped PPy had better cycling stability, losing only 10% of its original energy storage capability after 5000 charge-discharge cycles at 1 A g-1. The best energy densities and power densities were 49.1 ± 0.2 Wh kg-1 and 2297 ± 15 W kg-1 (ClO4 --doped PPy) and 47.8 ± 1.5 Wh kg-1 and 2191 ± 91 W kg-1 (pTS-doped PPy), respectively, which indicates that through statistical tools, the optimal synthesis conditions are refined to take advantage of the energy storage properties of this polymer.
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Affiliation(s)
| | | | - Pablo Ortiz
- Department
of Chemical Engineering, Universidad de
los Andes, Bogotá 111711, Colombia
| | - María T. Cortés
- Department
of Chemistry, Universidad de los Andes, Bogotá 111711, Colombia
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4
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Torres-García D, Pérez-Torres A, Manoutcharian K, Orbe U, Servín-Blanco R, Fragoso G, Sciutto E. GK-1 peptide reduces tumor growth, decreases metastatic burden, and increases survival in a murine breast cancer model. Vaccine 2017; 35:5653-5661. [PMID: 28890195 DOI: 10.1016/j.vaccine.2017.08.060] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [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: 06/07/2017] [Revised: 08/10/2017] [Accepted: 08/19/2017] [Indexed: 12/31/2022]
Abstract
GK-1 is a parasite-derived peptide adjuvant of 18 amino acid-length that enhances T-cell function and increases survival in B16-F10 melanoma tumor-bearing mice. This study was designed to evaluate in vivo the antitumor efficacy of GK-1 on 4T1 mouse mammary carcinoma. BALB/c mice with palpable primary tumors were weekly intravenously injected three times with saline solution or three different concentrations (10, 50, or 100μg per mouse) of GK-1. GK-1 significantly increased lifespan (p<0.0001) and reduced the primary tumor weight (p=0.014) and volume (p<0.0001) with respect to control mice, with no statistically significant differences among GK-1 doses. At the primary tumor, we found increased necrotic areas associated with a reduction in tumor mass, as well as an increase in the antitumor cytokine IL-12. Especially encouraging is the ability of GK-1 to reduce the number of lung metastasis (p=0.006) disregarding the dose used. The participation of IL-6 in metastasis development and the decreased levels of CCL-2, CCL-3, TNF-α, CXCL-9, GM-CSF, and b-FGF found in lungs of GK-1-treated mice is discussed. Our study supports the effectiveness of GK-1 as an antineoplastic agent that merits further exploration in combination with other therapeutic approaches in future translational studies.
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Affiliation(s)
- D Torres-García
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - A Pérez-Torres
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - K Manoutcharian
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - U Orbe
- Departamento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - R Servín-Blanco
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - G Fragoso
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico
| | - E Sciutto
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, 04510 Mexico City, Mexico.
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5
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Villaseñor-Cardoso MI, Salaiza N, Delgado J, Gutiérrez-Kobeh L, Pérez-Torres A, Becker I. Mast cells are activated by Leishmania mexicana LPG and regulate the disease outcome depending on the genetic background of the host. Parasite Immunol 2011; 30:425-34. [PMID: 18507782 DOI: 10.1111/j.1365-3024.2008.01042.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The regulatory effect of mast cells on the pathogenesis of leishmaniasis is unclear. We report a comparative analysis of TLR2 membrane expression, TNF-α, IL-10 and MIP-1α production, and granule release of bone marrow-derived mast cells (BMMCs) from susceptible BALB/c and resistant C57BL/6 mice, stimulated in vitro with Leishmania mexicana lipophosphoglycan (LPG). We studied the kinetics of mast cell degranulation and parasite numbers in lesions of both mouse strains infected with L. mexicana. We found that BMMCs of C57BL/6 mice expressed more TLR2 and produced higher levels of both cytokines and MIP-1α, whereas BALB/c BMMCs significantly augmented their granule release. Lesions of BALB/c mice showed higher levels of degranulated mast cells at 3 h of infection, whereas after 3 days of infection, the number of degranulated mast cells in C57BL/6 was higher than in BALB/c lesions. Throughout infection, BALB/c mice harboured more parasites. The regulatory effect of mast cells seems to depend on the genetic background of the host: mast cells of BALB/c mice facilitate disease progression due to an augmented inflammatory response early in the infection, whereas mast cells of C57BL/6 mice produce cytokines that regulate inflammation and maintain an elevated number of immune cells in the lesions, promoting disease control.
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Affiliation(s)
- M I Villaseñor-Cardoso
- Departamento de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, México, D.F., México
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6
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Reyes-Montes MR, Rodríguez-Arellanes G, Pérez-Torres A, Rosas-Rosas AG, Parás-García A, Juan-Sallés C, Taylor ML. Identification of the source of histoplasmosis infection in two captive maras (Dolichotis patagonum) from the same colony by using molecular and immunologic assays. Rev Argent Microbiol 2009; 41:102-104. [PMID: 19623900] [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: 05/28/2023] Open
Abstract
Histoplasma capsulatum was isolated from the spleen of a first infected mara (Dolichotis patagonum) and from a second mara's liver and adrenal gland, both in the same colony at the Africam Safari, Puebla, Mexico. Studies of H. capsulatum isolates, using nested-PCR of a 100-kDa protein coding gene (Hcp100) fragment and a two-primer RAPD-PCR method, suggest that these isolates were spreading in the environment of the maras' enclosure. By using a Dot-ELISA method, sera from mice inoculated with three homogenates of soil samples from the maras' enclosed space developed positive brown spot reactions to a purified H. capsulatum antigen, which identified the probable source of the maras' infection.
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Affiliation(s)
- M R Reyes-Montes
- Departamento de Microbiología-Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de Mexico, DF Mexico
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7
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Toriello C, Pérez-Torres A, Burciaga-Díaz A, Navarro-Barranco H, Pérez-Mejía A, Lorenzana-Jiménez M, Mier T. Lack of acute pathogenicity and toxicity in mice of an isolate of Metarhizium anisopliae var. anisopliae from spittlebugs. Ecotoxicol Environ Saf 2006; 65:278-87. [PMID: 16139361 DOI: 10.1016/j.ecoenv.2005.07.016] [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] [Received: 09/01/2004] [Revised: 05/27/2005] [Accepted: 07/06/2005] [Indexed: 05/04/2023]
Abstract
A monospore strain of Metarhizium anisopliae var. anisopliae (EH-479/2), isolated in Mexico from Aeneolamia sp., was tested for oral acute intragastric pathogenicity and toxicity in CD-1 mice, including a thorough histological study. Animals were inoculated by gavage with one dose (10(8) conidia/animal) of viable (72 mice) and nonviable (24 mice) conidia and compared to 18 control mice. Clinical observations were done daily; mycological and histological tests were performed during necropsies at days 3, 10, 17, and 21 after the inoculation. At the end of the study, no mice showed clinical symptoms of illness, and the animals' mean weight corresponded to that of healthy adults. No inflammatory reactions were identified in analyzed organs, suggesting the nonimmunogenic status of this fungal strain. Evidence of fungal germination was noted in two lymph nodes and in liver and lung of one dead mouse, out of 72 viable-conidia treated mice. There was no evidence of toxicity symptoms in mice inoculated with nonviable conidia. The results obtained support the nonpathogenic and nontoxic status of this fungal strain when administered in a sole intragastric dose in mice.
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Affiliation(s)
- C Toriello
- Departamento de Microbiología y Parasitología, Mexico.
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8
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Segura-Velázquez R, Pérez-Torres A, Rosas G, Toledo A, Restelli M, Acosta E, Corral R, Rosetti F, Fragoso G, Grinstein S, Sciutto E. A novel synthetic adjuvant effectively enhances the immunogenicity of the influenza vaccine. Vaccine 2006; 24:1073-80. [PMID: 16202486 DOI: 10.1016/j.vaccine.2005.09.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2005] [Revised: 08/25/2005] [Accepted: 09/05/2005] [Indexed: 11/20/2022]
Abstract
Influenza vaccination is a key intervention to reduce morbidity and mortality provoked by this disease. To date, the challenge of improving its efficacy remains unmet. The immunogenic synthetic peptide GK1 from Taenia crassiceps cysticerci was tested herein in its capacity as adjuvant, co-administered with the inactivated anti-influenza vaccine before and after challenge with influenza virus in both young and aged mice. Co-administration of GK1 with the influenza vaccine increased levels of anti-influenza antibodies in aged mice before and after infection, reduced the local inflammation that accompanied influenza vaccination itself and favored virus clearance after infection in both young and aged mice.
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Affiliation(s)
- R Segura-Velázquez
- Instituto de Investigaciones Biomédicas, A.P. 70228, Ciudad Universitaria, 04510 México, D.F., México
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9
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Aguirre-García MM, Escalona-Montaño AR, Bakalara N, Pérez-Torres A, Gutiérrez-Kobeh L, Becker I. Leishmania major: detection of membrane-bound protein tyrosine phosphatase. Parasitology 2006; 132:641-9. [PMID: 16393367 DOI: 10.1017/s0031182005009595] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Revised: 09/09/2005] [Accepted: 10/14/2005] [Indexed: 11/07/2022]
Abstract
PTPases have been reported as a virulence factor in different pathogens. Recent studies suggest that PTPases play a role in the pathogenesis of Leishmania infections through activation of macrophage PTPases by the parasite. We report here the presence of a membrane-bound PTPase in Leishmania major promastigotes. We detected differences in the PTPases present in the procyclic and metacyclic stages of promastigotes. In metacyclic promastigotes, the PTPase activity was totally inhibited by specific PTPase and serine/threonine inhibitors, whereas in procyclic promastigotes the PTPase activity was inhibited only with PTPase inhibitors. Two antibodies against the catalytic domains of the human placental PTPase1B and a PTPase from Trypanosoma brucei cross-reacted with a 55-60 kDa molecule present in the soluble detergent-extracted fraction of a Leishmania homogenate. Metacyclic promastigotes expressed more of this molecule than parasites in the procyclic stage. Yet the specific activity of the enzyme was lower in metacyclic than in procyclic promastigotes. Ultrastructural localization of the enzyme showed that it was more membrane-associated in metacyclic promastigotes, whereas in procyclic promastigotes it was scattered throughout the cytoplasm. This is the first demonstration of a PTPase present in Leishmania major promastigotes that differs in expression, activity and ultrastructural localization between the procyclic and metacyclic stages of the parasite's life-cycle.
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Affiliation(s)
- M M Aguirre-García
- Departamento de Medicina Experimental, Facultad de Medicina, Universidad Nacional Autónoma de México, México, D.F., México.
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Abstract
Mammalian Langerhans cells (LC) are epidermal dendritic cells which originate in bone marrow and migrate toward the T cell area of lymph nodes, where they act as professional antigen-presenting cells. A variety of cell surface markers, such as the ectoenzyme adenosine triphosphatase (ATPase), Ia and CDla antigens, have been used extensively to identify LC. Ultrastructural identification of this cell type in the mammalian epidermis is made by the demonstration of a typical and unique cytoplasmic organelle, the Birbeck granule (BG). Although we had earlier demonstrated the coexpression of ATPase and Ia antigens on epidermal dendritic cells of the chicken epidermis, the presence of the BG has not previously been documented. The aim of the present study was to investigate whether chicken epidermal LC-like cells possess an organelle similar to the BG, and thus to complete their identification. Our findings are the first demonstration of characteristic rod-shaped, racket-shaped and disc-shaped intracytoplasmic organelles, morphologically similar to the mammalian BG, in avian LC.
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Affiliation(s)
- A Pérez-Torres
- Departamento de Biologia Cellular y Tisular, Facultad de Medicina, UNAM, DF, Mexico.
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11
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Salaiza-Suazo N, Volkow P, Tamayo R, Moll H, Gillitzer R, Pérez-Torres A, Pérez-Montfort R, Domínguez JD, Velasco-Castrejón O, Crippa M, Becker I. Treatment of two patients with diffuse cutaneous leishmaniasis caused by Leishmania mexicana modifies the immunohistological profile but not the disease outcome. Trop Med Int Health 1999; 4:801-11. [PMID: 10632987 DOI: 10.1046/j.1365-3156.1999.00491.x] [Citation(s) in RCA: 30] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Two patients with diffuse cutaneous leishmaniasis caused by Leishmania mexicana were treated with two leishmanicidal drugs (pentamidine and allopurinol) combined with recombinant interferon-gamma restoring Th-1 favouring conditions in the patients. Parasites decreased dramatically in the lesions and macrophages diminished concomitantly, while IL-12-producing Langerhans cells and interferon-gamma- producing NK and CD8 + lymphocytes increased in a reciprocal manner. The CD4+/CD8 + ratio in the peripheral blood normalized. During exogenous administration of interferon-gamma the parasites' capacity to inhibit the oxidative burst of the patients' monocytes was abolished. Even though Th-1-favouring conditions were restored, both patients relapsed two months after therapy was discontinued. We conclude that the tendency to develop a disease-promoting Th-2 response in DCL patients is unaffected by, and independent of, parasite numbers. Even though intensive treatment in DCL patients induced Th-1 disease restricting conditions, the disease-promoting immunomodulation of few persistent Leishmania sufficed to revert the immune response.
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Affiliation(s)
- N Salaiza-Suazo
- Departamento de Medicina Experimental, Faculdad de Medicina, UNAM, Mexico
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12
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Becker I, Pérez-Montfort R, Pérez-Torres A, Rondán-Zárate A, Montfort I, Pérez-Tamayo R. Entamoeba histolytica: localization of a 30-kDa cysteine proteinase using a monoclonal antibody. Exp Parasitol 1996; 82:171-81. [PMID: 8617344 DOI: 10.1006/expr.1996.0022] [Citation(s) in RCA: 9] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We produced a monoclonal antibody against a major cysteine proteinase of 30kDa from trophozoites of Entamoeba histolytica strain HM1:IMSS. The specificity of the monoclonal antibody was confirmed by specific inhibition of azocasein digestion and by electrophoretic analysis, in the presence of sodium dodecyl sulfate or on a substrate gel, of the antigen precipitated by the antibody. Immunofluorescent staining of trophozoites with the monoclonal antibody revealed heterogeneity in the intensity of whole cell fluorescence and subcellular localization of the stain. The latter was also observed in trophozoites, which were stained by conventional immunohistochemical methods, from experimental liver abscesses in hamsters. Ultrastructural analysis showed antigen distributed mainly in clear amorphous zones in the cytoplasm, which were not limited by a visible membrane. Proteinases are translocated from these compartments to phagocytic vacuoles after trophozoites ingest erythrocytes, suggesting that these regions might be a lysosomal equivalent of this primitive eukaryotic cell.
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Affiliation(s)
- I Becker
- Departamento de Medicina Experimental, Facultad de Medicina U.N.A.M., Mexico City D.F., Mexico
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13
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Abstract
In mammalian epidermis, Langerhans cells (LC) are the only antigen-presenting dendritic cells that possess the ectoenzyme adenosine triphosphase (ATPase) and constitutively express class II molecules encoded by the major histocompatibility complex. Recently, we demonstrated the presence of LC in chicken epidermis. The aim of the present study is to demonstrate the presence of LC-like cells in turtle Kinosternum integrum, epidermis by light and ultrastructural ATPase histochemistry. ATPase-positive dendritic cells were observed in epidermal sheets whose maximum mean number was 192 cells/mm2. Electron microscopy for ATPase stained sections showed an electrondense precipitate in the plasma membrane of dendritic clear cells located among basal and suprabasal keratinocytes, ultrastructurally similar to LC. In serial sections, some dendritic cells showed LC (Birbeck) granules. The present study demonstrates for the first time ATPase-positive dendritic cells, morphologically similar to LC, in reptilian epidermis.
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Affiliation(s)
- A Pérez-Torres
- Departmento de Biología Celular y Tisular, Facultad de Medicina, Universidad Nacional Autónoma de México, México, D.F
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