Influence of grapevine (Vitis vinifera L.) on cover crops : a biomathematical model of the transition of amensalism to comensalism

En este trabajo se estudia la dinámica de transición en la interacción entre vid (Vitis vinifera L.) y cultivo de cobertura. A partir de datos obtenidos en un ensayo de campo se postuló un modelo estadístico para investigar dicha interacción biológica y se pudo determinar que el sistema vid-cultivo de cobertura cambió de una interacción biológica del tipo comensalismo a otra de amensalismo, siendo la vid la que no se ve afectada. Sobre la base de esta información, se formuló un modelo biomatemático para describir esta interacción, se estimaron los parámetros del mismo y se analizó la estabilidad de los puntos de equilibrio. Se evidencia en el presente estudio que el cultivo de cobertura no afecta el crecimiento de la vid, durante el período considerado en el ensayo.In this paper, we study the dynamics of transition in the interaction between vine (Vitis vinifera L.) and cover crop. From data obtained in a field essay, we propose a statistical model to investigate such biological interaction and we could determine that the vine-cover crop system changed from a biological interaction of commensalism type to another of amensalism type, being the vine not affected. Based on this information, we formulate a biomathematical model to describe this interaction, we estimate its parameters, and analyze the stability of the equilibrium points. It is evident, in this study, that the cover crop does not affect vine growth during the period considered in the essay.Fil: Bageta, Carlos Rubén. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Alberto, Marcelo. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Sartor, Carmen. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Cecconato, Adrián. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Bevaqua, Alicia. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Tirador, Marta. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Garriga, Marcela. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Nodaro, Verónica. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Quiroga, Alejandro. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Uliarte, Ernesto. Universidad Nacional de Cuyo. Facultad de Ciencias Agraria

Human infectiousness and parasite load in chronic patients seropositive for Trypanosoma cruzi in a rural area of the Argentine Chaco

A key parameter in the transmission of vector-borne infections, including Chagas disease, is the ability of the different host species to transmit the parasite to the vector (infectiousness). Here, we determined infectiousness to the vector of Trypanosoma cruzi-seropositive humans examined by artificial xenodiagnosis (XD), established its relationship with T. cruzi DNA levels (a surrogate of intensity of parasitemia) quantified by real-time PCR (qPCR), and assessed whether infectiousness was associated with the body mass index (BMI), age, ethnic background and parasite genotype. XD was performed to 117 T. cruzi-seropositive residents from Pampa del Indio and parasite load was quantified in 81 of them. Using optical microscopy (OM) 33.6% of the seropositive people tested were infectious and this fraction nearly doubled (66.0%) when XD triatomines were examined by kDNA-PCR. The mean infectiousness (defined as the percentage of all infected triatomines detected by OM at any time point among the total number of insects examined by OM 30 days post-feeding) was 5.2%, and the mean parasite load was 0.51 parasite equivalents per ml. Infectiousness to the vector was associated negatively with age and BMI, and positively with the detection of parasitemia by kDNA-PCR, and parasite load by qPCR in bivariate analysis. Patients with a positive XD by OM exhibited a significantly higher mean parasite load. Using multiple regression, infectiousness was associated with parasite load (positively) and with the household presence of T. infestans and Qom ethnic group (negatively); no significant association was observed with age or its interaction with ethnicity. We did not find significant associations between identified DTUs and infectiousness or parasite load. Infectiousness was aggregated: 18% of the people examined by XD generated 80% of the infected triatomines. Detecting and treating the super-infectious fraction of the infected human would disproportionally impact on domestic transmission risks. Nonetheless, treatment of all eligible infected people who meet the inclusion criteria regardless of their parasitemia should be ensured to improve their prognosis.Fil: Macchiaverna, Natalia Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Enriquez, Gustavo Fabián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Bua, Jacqueline Elena. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”. Instituto Nacional de Parasitología "Dr. Mario Fatala Chaben”; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernandez, Maria del Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Sartor, Paula Andrea. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas y Naturales y Agrimensura; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gurtler, Ricardo Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Cardinal, Marta Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentin

Risk Factors and Outcomes of Infections by Multidrug-Resistant Gram-Negative Bacteria in Patients Undergoing Hematopoietic Stem Cell Transplantation

Abstract The objective of this study was to determine risk factors and outcomes of infections by multidrug-resistant gram-negative (MDR GN) bacteria in 241 recipients of hematopoietic stem cell transplantation (HSCT). The cumulative incidence of infections was 10.5% (95% CI, 12.0% to 25.8%), with 57% of infections occurring during the period of severe neutropenia (neutrophil count  6 /L). In multivariate analysis, allogeneic transplant and colonization with MDR GN bacteria at admission to the transplant unit were significantly associated with an increased risk of infection. Although we observed neither transplant-related mortality (TRM) nor deaths due to infections by MDR GN bacteria after autologous transplant, in the allogeneic setting a significant difference was reported in terms of overall survival (OS) and TRM between patients who developed infections and those who did not (1-year OS, 39% versus 68%; 1-year TRM, 42% versus 19%). In multivariate analysis, refractory disease and development of grades III to IV graft-versus-host disease (GVHD) were factors that affected both TRM and OS, whereas occurrence of infections by MDR GN pathogens significantly reduced OS. We conclude that eligibility to allogeneic HSCT in MDR GN bacteria carriers should be carefully evaluated together with all other factors that independently influence outcome (disease status, donor, and GVHD risk)

Influencia de la vid (Vitis vinifera L.) sobre cultivos de cobertura: un modelo biomatemático de la transición de amensalismo a comensalismo

In this paper, we study the dynamics of transition in the interaction between vine (Vitis vinifera L.) and cover crop. From data obtained in a field essay, we propose a statistical model to investigate such biological interaction and we could determine that the vine-cover crop system changed from a biological interaction of commensalism type to another of amensalism type, being the vine not affected. Based on this information, we formulate a biomathematical model to describe this interaction, we estimate its parameters, and analyze the stability of the equilibrium points. It is evident, in this study, that the cover crop does not affect vine growth during the period considered in the essay.En este trabajo se estudia la dinámica de transición en la interacción entre vid (Vitisvinifera L.) y cultivo de cobertura. A partir de datos obtenidos en un ensayo de campo ser postuló un modelo estadístico para investigar dicha interacción biológica y se pudo determinar que el sistema vid-cultivo de cobertura cambió de una interacción biológica del tipo comensalismo a otra de amensalismo, siendo la vid la que no se ve afectada. Sobre la base de esta información, se formuló un modelo biomatemático para describir esta interacción, se estimaron los parámetros del mismo y se analizó la estabilidad de los puntos de equilibrio. Se evidencia en el presente estudio que el cultivo de cobertura no afecta el crecimiento de la vid, durante el período considerado en el ensayo. &nbsp

Metabolically-Defined Body Size Phenotypes and Risk of Endometrial Cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Background: Obesity is a risk factor for endometrial cancer but whether metabolic dysfunction is associated with endometrial cancer independent of body size is not known. Methods: The association of metabolically defined body size phenotypes with endometrial cancer risk was investigated in a nested case-control study (817 cases/ 817 controls) within the European Prospective Investigation into Cancer and Nutrition (EPIC). Concentrations of C-peptide were used to define metabolically healthy (MH; _1st tertile) status among the control participants. These metabolic health definitions were combined with normal weight (NW); body mass index (BMI)_25 kg/m2 or WC >_80 cm or WHR >_0. 8) status, generating four phenotype groups for each anthropometric measure: (i) MH/NW, (ii) MH/OW, (iii) MU/ NW, and (iv) MU/OW. Results: In a multivariable-adjusted conditional logistic regression model, compared with MH/NW individuals, endometrial cancer risk was higher among those classified as MU/NW [ORWC, 1.48; 95% confidence interval (CI), 1.05-2.10 and ORWHR, 1.68; 95% CI, 1.21- 2.35] and MU/OW (ORBMI, 2.38; 95% CI, 1.73-3.27; ORWC, 2.69; 95% CI, 1.92-3.77 and ORWHR, 1.83; 95% CI, 1.32-2.54). MH/OW individuals were also at increased endometrial cancer risk compared with MH/NW individuals (ORWC, 1.94; 95% CI, 1.24-3.04). Conclusions: Women with metabolic dysfunction appear to have higher risk of endometrial cancer regardless of their body size. However, OW status raises endometrial cancer risk even among women with lower insulin levels, suggesting that obesity related pathways are relevant for the development of this cancer beyond insulin. Impact: Classifying women by metabolic health may be of greater utility in identifying those at higher risk for endometrial cancer than anthropometry per se

Polyphenol Intake and Epithelial Ovarian Cancer Risk in the European Prospective Investigation into Cancer and Nutrition (EPIC) Study

We thank Bertrand Hemon for his valuable help with the EPIC database. We also thank the Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, and the National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands; Public Health Directorate, Asturias, Spain; the Oxford University, the Cambridge University, and the Imperial College of London, the UK, for their contribution and ongoing support to the EPIC Study. The authors also express their gratitude to all participants in the EPIC cohorts for their invaluable contribution to the study. This research was funded by the Women's Health Dexeus Foundation (R.Z.-R.). The coordination of EPIC is financially supported by the International Agency for Research on Cancer (IARC) and also by the Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, which has additional infrastructure support provided by the NIHR Imperial Biomedical Research Centre (BRC). The national cohorts are supported by: Danish Cancer Society (Denmark); Ligue Contre le Cancer, Institut Gustave Roussy, Mutuelle Generale de l'Education Nationale, Institut National de la Sante et de la Recherche Medicale (INSERM) (France); German Cancer Aid, German Cancer Research Center (DKFZ), German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), Federal Ministry of Education and Research (BMBF) (Germany); Associazione Italiana per la Ricerca sul Cancro-AIRC-Italy, Compagnia di SanPaolo and National Research Council (Italy); Dutch Ministry of Public Health, Welfare and Sports (VWS), Netherlands Cancer Registry (NKR), LK Research Funds, Dutch Prevention Funds, Dutch ZON (Zorg Onderzoek Nederland), World Cancer Research Fund (WCRF), Statistics Netherlands (The Netherlands); Health Research Fund (FIS)-Instituto de Salud Carlos III (ISCIII), Regional Governments of Andalucia, Asturias, Basque Country, Murcia and Navarra, and the Catalan Institute of Oncology-ICO (Spain); Swedish Cancer Society, Swedish Research Council and County Councils of Skane and Vasterbotten (Sweden); Cancer Research UK (14136 to EPIC-Norfolk; C8221/A29017 to EPIC-Oxford), Medical Research Council (1000143 to EPIC-Norfolk; MR/M012190/1 to EPIC-Oxford) (United Kingdom). We thank CERCA Program/Generalitat de Catalunya for institutional support. R.Z.-R. would like to thank the "Miguel Servet" program (CPII20/00009) from the Institute of Health Carlos III (Spain) and the European Social Fund (ESF).Despite some epidemiological evidence on the protective effects of polyphenol intake on epithelial ovarian cancer (EOC) risk from case-control studies, the evidence is scarce from prospective studies and non-existent for several polyphenol classes. Therefore, we aimed to investigate the associations between the intake of total, classes and subclasses of polyphenols and EOC risk in a large prospective study. The study was conducted in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, which included 309,129 adult women recruited mostly from the general population. Polyphenol intake was assessed through validated country-specific dietary questionnaires and the Phenol-Explorer database. During a mean follow-up of 14 years, 1469 first incident EOC cases (including 806 serous, 129 endometrioid, 102 mucinous, and 67 clear cell tumours) were identified. In multivariable-adjusted Cox regression models, the hazard ratio in the highest quartile of total polyphenol intake compared with the lowest quartile (HRQ4vsQ1) was 1.14 (95% CI 0.94–1.39; p-trend = 0.11). Similarly, the intake of most classes and subclasses of polyphenols were not related to either overall EOC risk or any EOC subtype. A borderline statistically significant positive association was observed between phenolic acid intake (HRQ4vsQ1 = 1.20, 95% CI 1.01–1.43; p-trend = 0.02) and EOC risk, especially for the serous subtype and in women with obesity, although these associations did not exceed the Bonferroni correction threshold. The current results do not support any association between polyphenol intake and EOC in our large European prospective study. Results regarding phenolic acid intake need further investigationJulius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, UtrechtNational Institute for Public Health and the Environment (RIVM), Bilthoven, the NetherlandsPublic Health Directorate, Asturias, SpainOxford UniversityWorld Health OrganizationNIHR Imperial Biomedical Research Centre (BRC)Danish Cancer SocietyLigue nationale contre le cancerInstitut Gustave RoussyMutuelle Generale de l'Education NationaleInstitut National de la Sante et de la Recherche Medicale (Inserm)Deutsche Krebshilfe Helmholtz Association Federal Ministry of Education & Research (BMBF)Fondazione AIRC per la ricerca sul cancroConsiglio Nazionale delle Ricerche (CNR)Dutch Ministry of Public Health, Welfare and Sports (VWS), Netherlands Cancer Registry (NKR), LK Research Funds Dutch Prevention Funds Netherlands Organization for Scientific Research (NWO) World Cancer Research Fund (WCRF), Statistics NetherlandsHealth Research Fund (FIS)-Instituto de Salud Carlos III (ISCIII)Swedish Cancer Society Swedish Research CouncilEuropean CommissionVasterbotten (Sweden)Cancer Research UK 14136 C8221/A29017UK Research & Innovation (UKRI) Medical Research Council UK (MRC)European Commission 1000143 MR/M012190/1CERCA Program/Generalitat de Catalunya CPII20/00009 Instituto de Salud Carlos IIIEuropean Social Fund (ESF)University of CambridgeImperial College of London, the UKWomen's Health Dexeus Foundatio

Integrating plant physiology into simulation of fire behavior and effects

Wildfires are a global crisis, but current fire models fail to capture vegetation response to changing climate. With drought and elevated temperature increasing the importance of vegetation dynamics to fire behavior, and the advent of next generation models capable of capturing increasingly complex physical processes, we provide a renewed focus on representation of woody vegetation in fire models. Currently, the most advanced representations of fire behavior and biophysical fire effects are found in distinct classes of fine-scale models and do not capture variation in live fuel (i.e. living plant) properties. We demonstrate that plant water and carbon dynamics, which influence combustion and heat transfer into the plant and often dictate plant survival, provide the mechanistic linkage between fire behavior and effects. Our conceptual framework linking remotely sensed estimates of plant water and carbon to fine-scale models of fire behavior and effects could be a critical first step toward improving the fidelity of the coarse scale models that are now relied upon for global fire forecasting. This process-based approach will be essential to capturing the influence of physiological responses to drought and warming on live fuel conditions, strengthening the science needed to guide fire managers in an uncertain future