The rise and fall of a secondary policy: la Joyanca (Guatemala)

International audiencePaleoenvironmental studies have recently made impressive contributions to our understanding of the Maya Lowland Terminal Classic crisis. They put much emphasis on the detection of drought episodes during the ninth century and later. There is no doubt that such events had an impact on Maya sociopolitical dynamics, although ninth-century droughts may have entailed relatively moderate rainfall reduction.Not only Maya agriculture but also urban populations were vulnerable to variation in precipitation.Moreover, the impact of reconstructed climatic events does not appear to have been as direct and synchronous as we would expect, and the concatenation of environmental and sociopolitical factors remains poorly investigated

Paysages, pratiques agricoles et dégradation des sols dans les Basses Terres mayas du Préclassique au Postclassique : le cas du site de "La Joyanca" (Petén, Guatemala)

International audienceLa péninsule du Yucatan a été le centre du développement de la civilisation maya, dont l'aire de peuplement s'étend sur 5 pays. Dans cet espace, les Basses Terres jouent un rôle fondamental dans le développement de la civilisation Classique à partir de 250 AD. Les conditions d'installation et de croissance de la civilisation classique ne vont pas sans poser certaines interrogations, en particulier en ce qui concerne le système agraire. Le système extensif, basé sur le maïs-courge-haricot, est complété par les apports d'un jardin-verger ou d'une horticulture à côté des habitations. Les résultats obtenus sur le site de la Joyanca confirment l'hypothèse d'un impact agricole précoce dans le Petén, dès le début du IIè millénaire

Resultados de la tercera temprada de campo 2001 del proyecto Peten noroccidente - La Joyanca, la libertad, Peten

International audienceSe presenta la información arqueológica y geográfica más reciente recuperada en el Noroccidente de Petén a través de investigaciones sistemáticas realizadas tanto en el centro y la periferia del sitio arqueológico La Joyanca como en la región circundante, proponiendo una visión de carácter local y regional. En general, ha existido una laguna de información y excavaciones en esta región de la tierras bajas mayas. Dichas investigaciones aqui resumidas en la presente ponencia aportan nuevos datos sobre las formas del asentamiento de La Joyanca, una "ciudad" de tercer orden, y de otros sitios estudiados en la región

Au pays maya des lacs et des marais recherches archéologiques et géographiques (1999-2001)

National audienceLes sociétés mayas des hautes terres ont connu un déclin culturel marqué à la fin du Préclassique (vers 100-250 apr. JC) au moment où, pour la plupart, les cités mayas des basses terres prenaient leur essor au début du Classique (250-300 apr. J.C.). Environ 600 ans plus tard, celles du Petén (Guatemala) étaient presque toutes abandonnées alors que celles des basses terres du nord connaissaient leur apogée jusqu'au début du Postclassique. En termes géographiques, il s'agit d'analyser l'évolution d'anthropo-systèmes formés en forêt tropicale humide de mousson, soit une des rares zones où s'est développée dans le passé une civilisation puissante, agricole et urbaine sur une longue durée. Le projet Petén nord-ouest La Joyanca a pour objet l'étude d'une communauté socio-politique de rang moyen, d'époque classique, située dans une région des basses terres jusqu'à présent quasiment inconnue du point de vue archéologique. Ce projet est particulier, d'une part car il associe une approche archéologique et géographique, cherchant à restituer l'histoire des hommes en même temps que l'histoire du milieu, d'autre part parce que l'initiative de cette recherche et son financement proviennent d'une compagnie pétrolière. Ce site de la Joyanca apporte des éléments nouveaux dans le corpus des "cités" mayas classiques des basses terres du Petén : désintégration du centre politico-religieux et des ensembles de palais, association étroite au centre, dans le temps et dans l'espace, des lieux de culte et d'un grand édifice politique complexe, faible densité de l'habitat

Identification of Conserved and HLA Promiscuous DENV3 T-Cell Epitopes

Anti-dengue T-cell responses have been implicated in both protection and immunopathology. However, most of the T-cell studies for dengue include few epitopes, with limited knowledge of their inter-serotype variation and the breadth of their human leukocyte antigen (HLA) affinity. In order to expand our knowledge of HLA-restricted dengue epitopes, we screened T-cell responses against 477 overlapping peptides derived from structural and non-structural proteins of the dengue virus serotype 3 (DENV3) by use of HLA class I and II transgenic mice (TgM): A2, A24, B7, DR2, DR3 and DR4. TgM were inoculated with peptides pools and the T-cell immunogenic peptides were identified by ELISPOT. Nine HLA class I and 97 HLA class II novel DENV3 epitopes were identified based on immunogenicity in TgM and their HLA affinity was further confirmed by binding assays analysis. A subset of these epitopes activated memory T-cells from DENV3 immune volunteers and was also capable of priming naïve T-cells, ex vivo, from dengue IgG negative individuals. Analysis of inter- and intra-serotype variation of such an epitope (A02-restricted) allowed us to identify altered peptide ligands not only in DENV3 but also in other DENV serotypes. These studies also characterized the HLA promiscuity of 23 HLA class II epitopes bearing highly conserved sequences, six of which could bind to more than 10 different HLA molecules representing a large percentage of the global population. These epitope data are invaluable to investigate the role of T-cells in dengue immunity/pathogenesis and vaccine design. © 2013 Nascimento et al

Pitfalls in assessing stromal tumor infiltrating lymphocytes (sTILs) in breast cancer

Abstract: Stromal tumor-infiltrating lymphocytes (sTILs) are important prognostic and predictive biomarkers in triple-negative (TNBC) and HER2-positive breast cancer. Incorporating sTILs into clinical practice necessitates reproducible assessment. Previously developed standardized scoring guidelines have been widely embraced by the clinical and research communities. We evaluated sources of variability in sTIL assessment by pathologists in three previous sTIL ring studies. We identify common challenges and evaluate impact of discrepancies on outcome estimates in early TNBC using a newly-developed prognostic tool. Discordant sTIL assessment is driven by heterogeneity in lymphocyte distribution. Additional factors include: technical slide-related issues; scoring outside the tumor boundary; tumors with minimal assessable stroma; including lymphocytes associated with other structures; and including other inflammatory cells. Small variations in sTIL assessment modestly alter risk estimation in early TNBC but have the potential to affect treatment selection if cutpoints are employed. Scoring and averaging multiple areas, as well as use of reference images, improve consistency of sTIL evaluation. Moreover, to assist in avoiding the pitfalls identified in this analysis, we developed an educational resource available at www.tilsinbreastcancer.org/pitfalls

Report on computational assessment of Tumor Infiltrating Lymphocytes from the International Immuno-Oncology Biomarker Working Group

Funder: U.S. Department of Health & Human Services | NIH | National Cancer Institute (NCI)Funder: National Center for Research Resources under award number 1 C06 RR12463-01, VA Merit Review Award IBX004121A from the United States Department of Veterans Affairs Biomedical Laboratory Research and Development Service, the DOD Prostate Cancer Idea Development Award (W81XWH-15-1-0558), the DOD Lung Cancer Investigator-Initiated Translational Research Award (W81XWH-18-1-0440), the DOD Peer Reviewed Cancer Research Program (W81XWH-16-1-0329), the Ohio Third Frontier Technology Validation Fund, the Wallace H. Coulter Foundation Program in the Department of Biomedical Engineering and the Clinical and Translational Science Award Program (CTSA) at Case Western Reserve University.Funder: Susan G Komen Foundation (CCR CCR18547966) and a Young Investigator Grant from the Breast Cancer Alliance.Funder: The Canadian Cancer SocietyFunder: Breast Cancer Research Foundation (BCRF), Grant No. 17-194Abstract: Assessment of tumor-infiltrating lymphocytes (TILs) is increasingly recognized as an integral part of the prognostic workflow in triple-negative (TNBC) and HER2-positive breast cancer, as well as many other solid tumors. This recognition has come about thanks to standardized visual reporting guidelines, which helped to reduce inter-reader variability. Now, there are ripe opportunities to employ computational methods that extract spatio-morphologic predictive features, enabling computer-aided diagnostics. We detail the benefits of computational TILs assessment, the readiness of TILs scoring for computational assessment, and outline considerations for overcoming key barriers to clinical translation in this arena. Specifically, we discuss: 1. ensuring computational workflows closely capture visual guidelines and standards; 2. challenges and thoughts standards for assessment of algorithms including training, preanalytical, analytical, and clinical validation; 3. perspectives on how to realize the potential of machine learning models and to overcome the perceptual and practical limits of visual scoring

Application of a risk-management framework for integration of stromal tumor-infiltrating lymphocytes in clinical trials

Funder: Breast Cancer Research Foundation (BCRF); doi: https://doi.org/10.13039/100001006Abstract: Stromal tumor-infiltrating lymphocytes (sTILs) are a potential predictive biomarker for immunotherapy response in metastatic triple-negative breast cancer (TNBC). To incorporate sTILs into clinical trials and diagnostics, reliable assessment is essential. In this review, we propose a new concept, namely the implementation of a risk-management framework that enables the use of sTILs as a stratification factor in clinical trials. We present the design of a biomarker risk-mitigation workflow that can be applied to any biomarker incorporation in clinical trials. We demonstrate the implementation of this concept using sTILs as an integral biomarker in a single-center phase II immunotherapy trial for metastatic TNBC (TONIC trial, NCT02499367), using this workflow to mitigate risks of suboptimal inclusion of sTILs in this specific trial. In this review, we demonstrate that a web-based scoring platform can mitigate potential risk factors when including sTILs in clinical trials, and we argue that this framework can be applied for any future biomarker-driven clinical trial setting

La structure de l’habitat du site maya classique de La Joyanca (Petén Nord-Ouest, Guatemala) dans son environnement local

International audienc

Neighborhoods in Classic Lowland Maya Societies: Their Identification and Definition from La Joyanca Case Study (Northwestern Peten, Guatemala)

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