Nutrients cause grassland biomass to outpace herbivory

Fil: Borer, Elizabeth T. University of Minnesota. Department of Ecology, Evolution and Behavior. St. Paul, MN, USA.Fil: Harpole, W. Stanley. Helmholtz Center for Environmental Research. Department of Physiological Diversity. Leipzig, Germany.Fil: Harpole, W. Stanley. German Centre for Integrative Biodiversity Research (iDiv). Leipzig, Germany.Fil: Harpole, W. Stanley. Martin Luther University Halle - Wittenberg. Saale, Germany.Fil: Adler, Peter B. Utah State University. Department of Wildland Resources and the Ecology Center. Logan, UT, USA.Fil: Arnillas, C. A. University of Toronto - Scarborough. Department of Physical and Environmental Sciences. Toronto, ON, Canada.Fil: Bugalho, M. N. University of Lisbon. School of Agriculture. Centre for Applied Ecology (CEABN-InBIO).Tapada da Ajuda, Lisbon, Portugal.Fil: Cadotte, Marc William. University of Toronto - Scarborough. Department of Biological Sciences. Toronto, ON, Canada.Fil: Caldeira, M. C. University of Lisbon. School of Agriculture. Forest Research Center. Tapada da Ajuda, Lisbon, Portugal.Fil: Campana, María Sofía. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.Fil: Campana, María Sofía. CONICET – Universidad de Buenos Aires. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs (‘consumer-controlled’). Alternatively, nutrient supply is predicted to increase biomass here herbivores alter community composition or are limited by factors other than food (‘resource-controlled’). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in aboveground live biomass\nover a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilizationinduced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk.grafs

Nutrients cause grassland biomass to outpace herbivory : author correction

Fil: Borer, Elizabeth T. University of Minnesota. Department of Ecology, Evolution and Behavior. St. Paul, MN, USA.Fil: Harpole, W. Stanley. Helmholtz Center for Environmental Research. Department of Physiological Diversity. Leipzig, Germany.Fil: Harpole, W. Stanley. German Centre for Integrative Biodiversity Research (iDiv). Leipzig, Germany.Fil: Harpole, W. Stanley. Martin Luther University Halle - Wittenberg. Saale, Germany.Fil: Adler, Peter B. Utah State University. Department of Wildland Resources and the Ecology Center. Logan, UT, USA.Fil: Arnillas, C. A. University of Toronto - Scarborough. Department of Physical and Environmental Sciences. Toronto, ON, Canada.Fil: Bugalho, M. N. University of Lisbon. School of Agriculture. Centre for Applied Ecology (CEABN-InBIO). Tapada da Ajuda, Lisbon, Portugal.Fil: Cadotte, Marc William. University of Toronto - Scarborough. Department of Biological Sciences. Toronto, ON, Canada.Fil: Caldeira, M. C. University of Lisbon. School of Agriculture. Forest Research Center. Tapada da Ajuda, Lisbon, Portugal.Fil: Campana, María Sofía. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.Fil: Campana, María Sofía. CONICET – Universidad de Buenos Aires. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA). Buenos Aires, Argentina.Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs (‘consumer-controlled’). Alternatively, nutrient supply is predicted to increase biomass where herbivores alter community composition or are limited by factors other than food (‘resource-controlled’). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in aboveground live biomass over a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilizationinduced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Increase in perivascular innervation of the human umbilical cord of newborns prenatally exposed to cocaine: impact on clinical variables

Introduction: Substance use during pregnancy represents a critical public health concern, linked with several harmful maternal and fetal consequences. Women are at their highest risk of developing a substance use disorder throughout their reproductive years. Particularly, cocaine use represents a worldwide problem. Given that vasoconstriction is modulated by sympathetic innervation, and cocaine is a sympathomimetic drug, we hypothesized that modifications in this type of innervation around umbilical vessels could compromise maternal filial blood flow, however, the impact of these changes remains to be evaluated. Objectives: Study the perivascular sympathetic innervation in newborns’ umbilical cord (UC) from cocaine pregnant users and seek for correlations between UC innervation and clinical manifestations. The impact of tobacco consumption was also addressed to identify possible deleterious exposure combinations. Methods: Perinatal clinical histories (SIP; by PAHO) of UC donors were evaluated (informed consent: INDT version-N°6/30-10-18). Analyses were conducted in: Control-group (clinically normal pregnancies; no pre-gestational/gestational pathologies); cocaine-group (self reported history of cocaine use during pregnancy); tobacco-group (self-reported history of tobacco smoking without other drug consumption during pregnancy). Influence of polyconsumption, gestational age and mother’s nutritional status were considered. Immunofluorescence: UC cryosections were co-labelled with anti-human PGP 9.5 (Abcam rabbit), a general nerve fiber marker; and anti-TH (Tyrosine Hydroxylase; Millipore-mouse), a specific marker for sympathetic fibers. Results: We found a subpopulation of newborns’ UC from cocaine users that had increased perivascular sympathetic innervation compared to healthy peers. Additionally, there was a negative correlation between the immunoreactive area occupied by nerve fibers in the umbilical arteries and the body weight, size and cephalic perimeter percentiles of newborns. No difference in age, size, weight and BMI (body mass index) of mothers from different groups was found. Also, we confirmed that 66% of UC from newborns of tobacco-group were not innervated. Conclusions: The subpopulation of newborns prenatally exposed to cocaine that had altered innervation in their umbilical arteries were those who presented the lowest size and weight. This supports our hypothesis and reveals a potential mechanism underlying the relationship between developmental disorders and prenatal drug exposure. Our results from the tobacco group will allow us to assess the effect of poly-substance use during pregnancies.Agencia Nacional de Investigación e InnovaciónPrograma de Desarrollo de las Ciencias Básica

Informe final del proyecto: Riesgos en la primera infancia del consumo de cocaína en el embarazo: estudio de la inervación del cordón umbilical del recién nacido

Un equipo multidisciplinario de investigadores abordó el estudio del impacto del consumo de drogas de abuso como un factor crítico en torno a las alteraciones del desarrollo en la primera infancia Los primeros resultados obtenidos en el Instituto de Investigaciones Biológicas Clemente Estable (IIBCE) mostraron que existe una sub-población de niños recién nacidos en el Hospital de Clínicas, de madres consumidoras de cocaína que presentan una inervación simpática exacerbada en los vasos sanguíneos de su cordón umbilical. El proyecto “Riesgos en la primera infancia del consumo de cocaína en el embarazo: estudio de la inervación del cordón umbilical del recién nacido” propone correlacionar los datos generados en IIBCE con datos cuantitativos recabados por la Encuesta de Nutrición, Desarrollo Infantil y Salud (ENDIS) 2018. El establecimiento de una asociación entre variables clínico-básicas del recién nacido con los datos de la ENDIS contribuirá a la generación de políticas públicas basadas en evidencias tendientes a resolver problemas de la primera infancia en Uruguay El proyecto fue apoyado a través del Fondo Sectorial de Salud en Primera Infancia junto al Programa “Uruguay Crece Contigo” del Ministerio de Desarrollo Social.Agencia Nacional de Investigación e Innovació

Informe final del proyecto: Riesgos en la primera infancia del consumo de cocaína en el embarazo: estudio de la inervación del cordón umbilical del recién nacido

Un equipo multidisciplinario de investigadores abordó el estudio del impacto del consumo de drogas de abuso como un factor crítico en torno a las alteraciones del desarrollo en la primera infancia Los primeros resultados obtenidos en el Instituto de Investigaciones Biológicas Clemente Estable (IIBCE) mostraron que existe una sub-población de niños recién nacidos en el Hospital de Clínicas, de madres consumidoras de cocaína que presentan una inervación simpática exacerbada en los vasos sanguíneos de su cordón umbilical. El proyecto “Riesgos en la primera infancia del consumo de cocaína en el embarazo: estudio de la inervación del cordón umbilical del recién nacido” propone correlacionar los datos generados en IIBCE con datos cuantitativos recabados por la Encuesta de Nutrición, Desarrollo Infantil y Salud (ENDIS) 2018. El establecimiento de una asociación entre variables clínico-básicas del recién nacido con los datos de la ENDIS contribuirá a la generación de políticas públicas basadas en evidencias tendientes a resolver problemas de la primera infancia en Uruguay El proyecto fue apoyado a través del Fondo Sectorial de Salud en Primera Infancia junto al Programa “Uruguay Crece Contigo” del Ministerio de Desarrollo Social.Agencia Nacional de Investigación e Innovació

The Role of α-Glucosidase in Germinating Barley Grains1[W][OA]

The importance of α-glucosidase in the endosperm starch metabolism of barley (Hordeum vulgare) seedlings is poorly understood. The enzyme converts maltose to glucose (Glc), but in vitro studies indicate that it can also attack starch granules. To discover its role in vivo, we took complementary chemical-genetic and reverse-genetic approaches. We identified iminosugar inhibitors of a recombinant form of an α-glucosidase previously discovered in barley endosperm (ALPHA-GLUCOSIDASE97 [HvAGL97]), and applied four of them to germinating grains. All four decreased the Glc-to-maltose ratio in the endosperm 10 d after imbibition, implying inhibition of maltase activity. Three of the four inhibitors also reduced starch degradation and seedling growth, but the fourth did not affect these parameters. Inhibition of starch degradation was apparently not due to inhibition of amylases. Inhibition of seedling growth was primarily a direct effect of the inhibitors on roots and coleoptiles rather than an indirect effect of the inhibition of endosperm metabolism. It may reflect inhibition of glycoprotein-processing glucosidases in these organs. In transgenic seedlings carrying an RNA interference silencing cassette for HvAgl97, α-glucosidase activity was reduced by up to 50%. There was a large decrease in the Glc-to-maltose ratio in these lines but no effect on starch degradation or seedling growth. Our results suggest that the α-glucosidase HvAGL97 is the major endosperm enzyme catalyzing the conversion of maltose to Glc but is not required for starch degradation. However, the effects of three glucosidase inhibitors on starch degradation in the endosperm indicate the existence of unidentified glucosidase(s) required for this process