Instituto De Investigaciones Research Articles

Trabajando con población migrante en Costa Rica: reflexiones sobre la relación entre organizaciones de ayuda y las bases para la acción colectiva

En este artículo reflexionamos sobre las funciones de organizaciones de ayuda a migrantes, y posibilidades de desarrollar acciones políticas colectivas. A través de los seminarios de migración y subjetividad del Instituto de Investigaciones Sociales de la Universidad de Costa Rica con profesionales que trabajan en las ONG para la atención a inmigrantes, se pudo hallar que la priorización de labores asistenciales en las organizaciones, la lucha por el financiamiento externo, y las diferencias en el enfoque de la temática migratoria son algunos de los obstáculos para la acción política colectiva. Los esfuerzos de algunas organizaciones se enfocan en la resolución de necesidades inmediatas como la regularización, mientras que el fortalecimiento de la población migrante como sujetos políticos parece secundario y este es un aspecto hacia el cual proponemos dirigir el trabajo con la población migrante.

SIMAC: Development and implementation of a coral reef monitoring network in Colombia

Significant coral reef decline has been observed in Colombia during the last three decades. However, due to the lack of monitoring activities, most of the information about health and changes was fragmentary or inadequate. To develop an expanded nation-wide reef-monitoring program, in 1998 INVEMAR (Instituto de Investigaciones Marinas y Costeras: "Colombian Institute of Marine and Coastal Research") designed and implemented SIMAC (Sistema Nacional de Monitorco de Arrecifes Coralinos en Colombia: "National Monitoring System of Coral Reefs in Colombia") with the participation of other institutions. By the end of 2003 the SIMAC network reached more than twice its initial size, covering ten reef areas (seven in the Caribbean and three in the Pacific), 63 reef sites and 263 permanent transects. SIMAC monitoring continued without interruption until 2008 and should persist in the long-term. The SIMAC has a large database and consists basically of water quality measurements (temperature, salinity, turbidity) and a yearly estimation of benthic reef cover, coral disease prevalence, gorgonian density, abundance of important mobile invertebrates, fish diversity and abundance of important fish species. A methods manual is available in the Internet. Data and results of SIMAC have been widely circulated through a summary report published annually since 2000 for the Colombian environmental agencies and the general public, as well as numerous national and international scientific papers and presentations at meetings. SIMAC information has contributed to support regional and global reef monitoring networks and databases (i.e. CARICOMP, GCRMN, ReefBase).

WWW.Farmakologiportalen.No – A Common National Database For Pharmacological Laboratory Services

CLiNiCAL diLi NETwoRkS ANd CoNSoRTiA: whAT LESSoNS hAVE wE LEARNT? R.J. Andrade Head, Department of Medicine and Gastroenterology Service, Instituto de Investigacion Biomedica de Malaga (IBIMA), Hospital Universitario Virgen de la Victoria, Universidad de Malaga, Malaga, Spain; and Centro de Investigacion Biomedica en Red de Enfermedades Hepaticas y Digestivas (CIBERehd), Madrid, Spain Drug-induced liver injury (DILI) is a rare but potentially severe adverse event concerning mostly patients but also pharmaceutical industry, clinicians, and regulatory authorities. The necessity of concerted efforts to obtain reliable information on DILI causal agents, phenotypes, and risk factors has stimulated groups in USA and Europe to develop large DILI prospective registries. The Spanish DILI Registry (www.spanishdili.uma.es) and the Drug-Induced Liver Injury Network (http://dilin.duke.edu) are collaborative multicenter networks with large databases and biosample collections of prospectively recorded DILI cases in Spain and the US, respectively, and subsequently important resources for hepatotoxicity studies. The Spanish DILI Registry has recently initiated a new branch into South America, the Spanish-Latin American DILI Network (SLATINDILI; www.slatindili.uma.es), and into Europe, leading the EuroProDILI Registry fostered by the European Association for the Study of the Liver. In this presentation I will discuss on how DILI registries have expanded our knowledge on this fascinating yet challenging and complex disease.

Rainfall intensity modulates the interaction between the marsh cordgrass Spartina densiflora and the mouse Akodon azarae

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 523:71-80 (2015) - DOI: https://doi.org/10.3354/meps11119 Rainfall intensity modulates the interaction between the marsh cordgrass Spartina densiflora and the mouse Akodon azarae Jesús Pascual*, Alejandro D. Canepuccia, Juan Alberti, Pedro Daleo, Oscar Iribarne Instituto de Investigaciones Marinas y Costeras (IIMyC), CONICET - UNMDP, Lab. Ecología, Dpto. Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, CC 573 Correo Central, B7600WAG, Mar del Plata, Argentina *Corresponding author: pascualjesu@gmail.com ABSTRACT: Changes in rainfall patterns caused by anthropogenic global climate change or planetary-scale events, such as the El Niño Southern Oscillation, can significantly affect the abundance and distribution of organisms. Despite the evidence of such effects on marine and terrestrial systems, ecological consequences of rainfall fluctuations in coastal marine ecosystems remain poorly understood. Here we evaluate the effects of rainfall intensity on the interaction between the cordgrass Spartina densiflora and Azara’s grass mouse Akodon azarae in a southwestern Atlantic salt marsh (Mar Chiquita coastal lagoon, Argentina). Field surveys showed that the abundance of A. azarae increased during rainy summers (i.e. El Niño 2005 and 2007) and had lowest values during dry summers (i.e. La Niña 2008). Salt content in sediment and plant tissue were negatively related with rainfall. In addition, field experiments showed that increased sediment salinity resulted in increased salt content in plant tissues. Elevated soil salinity also increased the proportion of senescent S. densiflora tissues and reduced plant growth. The consumption of S. densiflora leaves by A. azarae also decreased with increased soil salinity. The proportion of S. densiflora in feces collected during the driest summer was very small. Therefore, changes in the abundance of A. azarae could be mediated by plant-rodent trophic interaction or by plant cover changes. In conclusion, rainfall fluctuations changed the abiotic environment (i.e. salinity), decreasing primary production and indirectly modifying habitat use by the omnivore A. azarae and its trophic interaction with S. densiflora. The present study provides evidence that rainfall can modify ecological processes that affect the structure and dynamics of coastal marine ecosystems. KEY WORDS: Climate change · Rainfall changes · Spartina densiflora · Akodon azarae · Habitat use Full text in pdf format PreviousNextCite this article as: Pascual J, Canepuccia AD, Alberti J, Daleo P, Iribarne O (2015) Rainfall intensity modulates the interaction between the marsh cordgrass Spartina densiflora and the mouse Akodon azarae. Mar Ecol Prog Ser 523:71-80. https://doi.org/10.3354/meps11119 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 523. Online publication date: March 16, 2015 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2015 Inter-Research.

Prostaglandin E2 inhibits the proinflammatory phenotype induced by TGF-β on monocyte-derived dendritic cells

Prostaglandin E2 inhibits the proinflammatory phenotype induced by TGF-β on monocyte-derived dendritic cells

Comprehensive investigation in patients affected by sperm macrocephaly and globozoospermia.

The aim of this study was to provide a comprehensive genetic/phenotypic characterization of subjects suffering infertility owing to sperm macrocephaly (n = 3) or globozoospermia (n = 9) and to investigate whether the patients' genetic status was correlated with the alteration of various sperm parameters. AURKC was sequenced in case of sperm macrocephaly while the DPY19L2 status has been analyzed by multiple approaches including a novel qPCR-based copy number assay in case of globozoospermia. Globozoospermic patients were also analyzed for SPACA1, a novel candidate gene herein tested for the first time in humans. The effect of the patients' genetic status was interrogated by implementing the molecular screening with the characterization of several sperm parameters: (i) routine sperm analysis, integrated with transmission electron microscopy; (ii) sperm fluorescent in situ hybridization (FISH) analysis; (iii) sperm DNA fragmentation (DF) analysis. Moreover, for the first time, we performed microsatellite instability analysis as a marker of genome instability in men with sperm macrocephaly and globozoospermia. Finally, artificial reproductive technology (ART) history has been reported for those patients who underwent the treatment. Macrocephalic patients had an AURKC mutation and >89% tetraploid, highly fragmented spermatozoa. DPY19L2 was mutated in all patients with >80% globozoospermia: the two homozygous deleted men and the compound heterozygous showed the severest phenotype (90-100%). The newly developed qPCR method was fully validated and has the potential of detecting also yet undiscovered deletions. DPY19L2 status is unlikely related to FISH anomalies and DF, although globozoospermic men showed a higher disomy rate and DF compared with internal reference values. No patient was mutated for SPACA1. Our data support the general agreement on the negative correlation between macro/globozoospermia and conventional intracytoplasmic sperm injection outcomes. Microsatellites were stable in all patients analyzed. The comprehensive picture provided on these severe phenotypes causing infertility is of relevance in the management of patients undergoing ART.

Una nueva especie del género Opuntia (Cactaceae) para el estado de Veracruz, México

Se describe e ilustra la Opuntia perotensis Scheinvar, Olalde & Gallegos, nueva especie de un nopal silvestre del Frijol Colorado, Cofre de Perote, Veracruz, México. La nueva especie estaba identificada como O. huajuapensis Bravo en el herbario del Instituto de Investigaciones Biológicas de la Universidad Veracruzana. Opuntia huajuapensis es una especie endémica de la mixteca oaxacense, distinguiéndose de O. perotensis , la cual presenta epidermis papilosa, cladodios con espinas en todas las aréolas, con algunos pelos negros; flores de dos colores; frutos subglobosos con paredes anchas; arilo piloso, semillas ubicadas en el centro del fruto y granos de polen de dos tipos morfológicos. Se considera que se trata de una especie nueva, posiblemente de origen híbrida, ubicada en la serie Criniferae Pfeiff.

Altered frequency of IL-10+ B cells in apolipoprotein E deficient mice with established atherosclerosis

Altered frequency of IL-10+ B cells in apolipoprotein E deficient mice with established atherosclerosis

Alterations in the frequency and phenotype of B cells during experimental atherosclerosis are associated with hipercholesterolemia

Alterations in the frequency and phenotype of B cells during experimental atherosclerosis are associated with hipercholesterolemia

Microparticles forming immune complexes in Rheumatoid Arthritis patients could be associated with the altered phenotype of classical and intermediate monocyte subsets

Microparticles forming immune complexes in Rheumatoid Arthritis patients could be associated with the altered phenotype of classical and intermediate monocyte subsets

Assessing the ability of two specific, immunodominant Taenia solium antigens to differentiate non-infected from cysticercotic subjects

Event Abstract Back to Event Assessing the ability of two specific, immunodominant Taenia solium antigens to differentiate non-infected from cysticercotic subjects Yuliet M. Diaz1, Gladis Fragoso1, Edda Sciutto1, Julio C. Carrero1, Ada N. Martínez2, Juan Pedro Laclette1 and Raúl J. Bobes1* 1 Universidad Nacional Autónoma de México, Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Mexico 2 Universidad Nacional Autónoma de México, Departamento de Patología, Facultad de Medicina Veterinaria y Zootecnia, Mexico INTRODUCTION: Human and porcine cysticercosis are infectious diseases associated to poverty and poor sanitary conditions. Cysticercosis is a severe public health issue and causes great economic losses at the rustic pork rearing industry in Mexico and other developing countries. Many variables can influence the current Immunodiagnostic methods and alter the assay sensitivity and specificity. This has prevented the development of a suitable diagnostic test for a highly specific diagnosis. OBJECTIVE: This work is aimed to find recombinant antigens or derivative peptides suitable to develop a more sensitive and specific diagnostic test for human and porcine cysticercosis. METHODS: Based on the amino acid sequence of two antigens identified in a previous study as specific for porcine cysticercosis (annexin B1 and cAMP-dependent kinase), peptides with the highest antigenicity rates were identified by bioinformatic tools. These peptides were evaluated for their suitability as antigen source in a cysticercosis ELISA, using serum samples from cysticercotic and non-cysticercotic pigs as antibody source. Additionally, the coding sequences for the selected antigens were cloned in a prokaryotic system to evaluate the diagnostic usefulness of the entire protein. RESULTS: Seven peptides with the highest antigenic index for annexin B1 and 12 peptides for cAMP-dependent kinase were selected. A series of ELISA experiments led us to identify those peptides that were most recognized by antibodies in pig serum samples. For annexin B1, 3 peptides out of 7 showed higher recognition, while 5 out of 12 peptides showed higher recognition for cAMP-dependent kinase. The cloning, expression, and purification of the recombinant proteins annexin B1 and cAMP-dependent kinase were also performed. CONCLUSIONS: The antigens evaluated in this work, annexin B1 and cAMP-dependent kinase include linear peptides which might be good candidates to be used in a diagnostic test for cysticercosis. Acknowledgements This work is supported in part by grants from PAPIIT-UNAM: IN228609-3 and CONACyT: 61334. Keywords: Cysticercosis, diagnosis, Antigenicity, Specific antigens, Taenia solium Conference: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología, Medellin, Colombia, 13 Oct - 16 Oct, 2015. Presentation Type: Poster Presentation Topic: Infectious and parasitic diseases Citation: Diaz YM, Fragoso G, Sciutto E, Carrero JC, Martínez AN, Laclette J and Bobes RJ (2015). Assessing the ability of two specific, immunodominant Taenia solium antigens to differentiate non-infected from cysticercotic subjects. Front. Immunol. Conference Abstract: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología. doi: 10.3389/conf.fimmu.2015.05.00191 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Apr 2015; Published Online: 14 Sep 2015. * Correspondence: PhD. Raúl J Bobes, Universidad Nacional Autónoma de México, Departamento de Inmunología, Instituto de Investigaciones Biomédicas, México, D. F., Mexico, rbobes@biomedicas.unam.mx Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Yuliet M Diaz Gladis Fragoso Edda Sciutto Julio C Carrero Ada N Martínez Juan Pedro Laclette Raúl J Bobes Google Yuliet M Diaz Gladis Fragoso Edda Sciutto Julio C Carrero Ada N Martínez Juan Pedro Laclette Raúl J Bobes Google Scholar Yuliet M Diaz Gladis Fragoso Edda Sciutto Julio C Carrero Ada N Martínez Juan Pedro Laclette Raúl J Bobes PubMed Yuliet M Diaz Gladis Fragoso Edda Sciutto Julio C Carrero Ada N Martínez Juan Pedro Laclette Raúl J Bobes Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Inhibins regulate peripheral Treg induction through modulation of dendritic cell function.

Event Abstract Back to Event Inhibins regulate peripheral Treg induction through modulation of dendritic cell function. SANDRA ORTEGA1*, Marisol De La Fuente Granada1, Roxana Olguín Alor1, Jesús Ramsés Chávez-Ríos1, Laura Bonifaz Alfonso2, Eduardo A. García-Zepeda1 and Gloria Soldevila Melgarejo1 1 UNAM, Depto de Inmunología, Instituto de Investigaciones Biomédicas, Mexico 2 Centro Médico Nacional Siglo XXI, IMSS, Mexico Inhibins and Activins, members of the Transforming Growth Factorb superfamily, participate in the immune system as key regulators of several cellular functions. Despite some reports indicate that Activins may regulate DC maturation and function, the role of Inhibins in these processes remains elusive. Here, we investigated the role of Inhibins in DC maturation and function and its impact in Treg induction and Th effector differentiation. Analysis of mature Inhα-/- BMDCs obtained after lipopolysaccharide (LPS) stimulation (mBMDC) showed a significant reduction in the surface expression of MHC II and CD86 (a semi-mature phenotype), and a concomitant increase in PD-L1, compared to WT mBMDC. In addition, the Inhα-/- mBMDC showed reduced migration towards CCL19 and CCL21 both in vitro chemotaxis assays as well as and in vivo, in in vivo adoptive competitive transfer assays, in comparison to WT. To evaluate if these findings correlated with a “tolerogenic” phenotype, functional responses were assayed showing that mBMDC from Inhα-/- displayed reduced capacity to induce proliferation of allogeneic CD4+ naïve T cells. This correlated with an increased induction of iTregs (CD25+Foxp3+) from CD4+ naïve T cells in the presence of low concentrations of anti-CD3 and TGFb as well as with increased absolute numbers of iTregs and nTreg (CD4+CD25+Foxp3+Helios- and Helios+, respectively) in peripheral lymph nodes of 4 week-old Inhα-/- mice compared to WT. Interestingly, Inhα-/- T cells showed a reduced induction of Tregs in the absence of APCs, suggesting an intrinsic role of Inhibins in the differentiation of T cells. Analysis of Th effector differentiation is currently being performed using an OVA-specific transgenic mouse model. Our data demonstrate for the first time a direct role of Inhibins in the regulation of DC mediated functions and point out the importance of Inhibin signaling to maintain the balance between inflammation and tolerance. Acknowledgements Work supported by PAPIIT, DGAPA, UNAM (Grant IN209615). Keywords: Inhibins, T cells diferentiation, Dendritic cells function, T regs induction, Dendritic cells maturation Conference: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología, Medellin, Colombia, 13 Oct - 16 Oct, 2015. Presentation Type: Poster Presentation Topic: Adaptive Immunity Citation: ORTEGA S, De La Fuente Granada M, Olguín Alor R, Chávez-Ríos J, Bonifaz Alfonso L, García-Zepeda E and Soldevila Melgarejo G (2015). Inhibins regulate peripheral Treg induction through modulation of dendritic cell function.. Front. Immunol. Conference Abstract: IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología. doi: 10.3389/conf.fimmu.2015.05.00374 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 15 May 2015; Published Online: 16 Sep 2015. * Correspondence: Ms. SANDRA ORTEGA, UNAM, Depto de Inmunología, Instituto de Investigaciones Biomédicas, México, D.F., Mexico, amyrisortega@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers SANDRA ORTEGA Marisol De La Fuente Granada Roxana Olguín Alor Jesús Ramsés Chávez-Ríos Laura Bonifaz Alfonso Eduardo A. García-Zepeda Gloria Soldevila Melgarejo Google SANDRA ORTEGA Marisol De La Fuente Granada Roxana Olguín Alor Jesús Ramsés Chávez-Ríos Laura Bonifaz Alfonso Eduardo A. García-Zepeda Gloria Soldevila Melgarejo Google Scholar SANDRA ORTEGA Marisol De La Fuente Granada Roxana Olguín Alor Jesús Ramsés Chávez-Ríos Laura Bonifaz Alfonso Eduardo A. García-Zepeda Gloria Soldevila Melgarejo PubMed SANDRA ORTEGA Marisol De La Fuente Granada Roxana Olguín Alor Jesús Ramsés Chávez-Ríos Laura Bonifaz Alfonso Eduardo A. García-Zepeda Gloria Soldevila Melgarejo Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Expansion and generation of Tregs cells with potential clinical application in kidney transplantation

Expansion and generation of Tregs cells with potential clinical application in kidney transplantation

Global transcriptome analysis of alveolar macrophage from tuberculosis patients and non-infected controls

Global transcriptome analysis of alveolar macrophage from tuberculosis patients and non-infected controls

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

IgG response to different stage-specific antigens of Mycobacterium tuberculosis

Effect of Dexamethasone, LPS, or INFγ on the production of TNFα, IL-12, IL-6, IL-10, CXCL8, CXCL10, and CLC3, by bovine macrophages infected in vitro with Mycobacterium avium paratuberculosis.

Effect of Dexamethasone, LPS, or INFγ on the production of TNFα, IL-12, IL-6, IL-10, CXCL8, CXCL10, and CLC3, by bovine macrophages infected in vitro with Mycobacterium avium paratuberculosis.

Naturally-ocurring biflavonoids modulate macrophage response in vitro and are atheroprotective in vivo

Naturally-ocurring biflavonoids modulate macrophage response in vitro and are atheroprotective in vivo

TIME COURSE MODIFICATIONS INDUCED BY PERINATAL ASPHYXIA IN RAT CNS

TIME COURSE MODIFICATIONS INDUCED BY PERINATAL ASPHYXIA IN RAT CNS

Radiocarbon Dating of Atacama (Chile) Snuff Trays: An Update on Stylistic and Chronological Correlations

The Atacama region of Chile has the highest concentration of hallucinogenic paraphernalia from prehistoric cemeteries on the planet. These artifacts have been studied since the late 19th century, primarily from the perspective of stylistic classification, which has been used to infer their temporal assignation. However, direct chronological dating of the snuff trays has not been addressed until now, through an interdisciplinary study conducted in San Pedro de Atacama on the psychotropic paraphernalia collection of the Instituto de Investigaciones Arqueológicas y Museo R.P. Gustavo Le Paige S.J. (IIAM), part of the Universidad Católica del Norte. In this study, samples were taken from eight snuff trays for radiocarbon dating and to develop a suitable procedure and protocol for sample extraction and handling of wooden archaeological pieces. This article provides the results of these activities by establishing the existence of a sequence of styles in the hallucinogenic paraphernalia that goes from the Middle to Late Intermediate period (about AD 300 to 1400), which shows that in this time-span there were two styles (Tiwanaku and local), and then both were replaced by a macroregional style.

Primer registro de Tlacuatzin canescens, (Mammalia, Didelphimorphia: Marmosidae) en Veracruz, México

Introduction: The Mexican Mouse Opossum ( Marmosa mexicana ) and the grayish mouse opossum ( Tlacuatzin canescens ) were the only two known species of tribu Marmosini (Mammalia, Didelphimorphi, Didelphidae) in Mexico. The genus Tlacuatzin and its species Tlacuatzin canescens are endemic. Its distribution extends from the south of the State of Sonora to the State of Chiapas. It is also found on the Islas Marias, in the state of Jalisco, in the Yucatan Peninsula, and in the State of Puebla. So far, T. canescens has not been previously sighted in the State of Veracruz or in the north coast of the Gulf of Mexico. This report describes the first official sighting of T. canescens from Veracruz, Mexico. Methods: The records were obtained: a) from voucher specimens deposited at the Coleccion Mastozoologica, Instituto de Investigaciones Biologicas, Universidad Veracruzana, and b) by accidentally trapping these mammals in botanical surveys conducted at the El Centro de Investigaciones Costeras La Mancha, Instituto de Ecologia A.C. and its surroundings. Results: The presence of T. canescens in Veracruz State was documented by nine records collected at three different localities, from the central region of Veracruz, Mexico. All the locations were found in deciduous forest areas. Discussion and Conclusions: These new records increase the species’ known geographic distribution in 139 km, on a straight line from the nearest locality found in the state of Puebla. It is important to recall that these locations are all located on both sides of the Sierra Madre Oriental Mountain system (average altitude higher than 2000 meters above sea level, between localities), which serves as a barrier between the populations of Puebla and Veracruz. Key words: Didelphimorphia, geographic distribution, local distribution, marsupial, opossum-souris cendre