G. L. Stebbins' most effective pollinator principle states that when pollinators are not limiting, plants are expected to specialize and adapt to the most abundant and effective pollinator species available. In this study, we quantify the effectiveness of bees, hummingbirds and hawkmoths in a Chilean population of (Phrymaceae), and examine whether flower traits are subject to pollinator-mediated selection by the most effective pollinator species during two consecutive years. Unlike most species in the pollinator community, the visitation rate of the recently arrived did not change substantially between years, which together with its high and stable pollen delivery to flower stigmas made this species the most important in the pollinator assemblage, followed by the solitary bee Flower traits were under significant selection in the direction expected for short-tongue bees, suggesting that is in the initial steps of adaptation to the highly effective exotic bumblebee Our results illustrate the applicability of Stebbins' principle for new invasive pollinators, and stress their importance in driving flower adaptation of native plant species, a critical issue in the face of biotic exchange and homogenization.
Introduction: Pubertal onset is triggered by multiple neuroendocrine interactions. The role of prepubertal IGF-1 in this process has not been explored in both sexes. Our objective is to analyze the association of prepubertal IGF-1 concentration with age at thelarche (B2) and menarche (M) in girls and age at gonadarche (G2) in boys. Methods: Longitudinal study (n=1196 boys and girls) within the Growth and Obesity Chilean cohort Study (GOCS). At ages ≈ 6.7 years blood sample for IGF-1. Subjects analyzed into 4 groups according to the onset age of the pubertal event. Results: Higher prepubertal IGF-1 levels were observed at earlier ages of thelarche (p=0.003) and menarche onset (p=0.041). A taller prepubertal height was observed at younger ages of thelarche and menarche (p=<0.001 and 0.002, respectively). The proportional hazard regression (HR) models showed that with an increase of 1 SD in IGF-1, the HR of presenting thelarche at younger ages was 1.25 and this association was maintained when adjusted for confounding variables. Similarly, the HR of presenting menarche at earlier ages was 1.21. This association was maintained only when adjusting for BMI but not using further confounders. In boys, prepubertal IGF-1 showed a tendency to be significantly higher in children with earlier gonadarche and taller height (both p<0.001). The HR of presenting gonadarche at younger ages was 1.22 and this association was maintained after adjusting for confounders. Conclusions: higher IGF-I levels in mid-childhood are associated with earlier puberty onset. The role of IGF-I in the onset of puberty requires further investigation.
Incidence of thyroid cancer in an oncological clinic of Santiago, Chile Background: In Chile, Thyroid cancer (TC) is included in a list of diseases that have a guaranteed access to treatment, endorsed by the Ministry of Health. The care burden of the disease will depend on its incidence. Aim: To estimate the incidence of TC in Chilean patients with access to thyroid surgery and describe its histopathological characteristics. Material and methods: Analysis of the registry of all thyroidectomies performed at a private oncological clinic in Metropolitan Santiago, between 2016 and 2018. Incidence was estimated the number of persons affiliated to an insurance system managed by the same clinic, separated by age and gender. Results: TC adjusted incidence varied from 60.8 cases per 100,000 persons/year in 2016 to 48.7 cases per 100,000 persons/ year in 2018. The proportion of microtumors was 34% when the diameter of all foci was considered. Papillary and follicular carcinomas were the pathological diagnoses in 96 and 2% of cases respectively. Twenty-one percent of tumors had extra-thyroidal invasion. Conclusions: The TC incidence herein reported is higher than the figure of 7.9 cases per 100,000 persons/year reported by us in 2014. This difference could be due to a true increase in the incidence of TC, following worldwide trends or to differences in the methods used in both studies.
Background: The use of convalescent plasma (CP) to treat COVID-19 has shown promising results; however, its effectiveness remains uncertain. The purpose of this study was to determine the safety and mortality of CP among patients hospitalized with COVID-19. Study Design and Methods: This multicenter, open-label, uncontrolled clinical trial is currently being conducted at nine hospitals in Chile. Patients hospitalized due to COVID-19 who were still within 14 days since symptom onset were classified into four groups: Patients with cancer and severe COVID-19. Patients with cancer and non-severe COVID-19. Patients with severe COVID-19 and patients with non-severe COVID-19 only. The intervention involved two 200-cc. CP transfusions with anti-SARS-CoV-2 IgG titers ≥ 1:320 collected from COVID-19-recovered donors. Results: 192 patients hospitalized for COVID-19 received CP transfusions. At the first transfusion, 90.6% fulfilled the criteria for severity, and 41.1% required mechanical ventilation. 11.5% of the patients had cancer. Overall 7-day and 30-day mortality since the first CP transfusion was 5.7% and 16.1% respectively. There were no differences at either time point in mortality between the four groups. Patients on mechanical ventilation when receiving CP had higher mortality rates than those who were not (22.8% vs. 11.5%; p = 0.037). Overall 30-day mortality was higher in patients over 65 than in younger patients (p = 0.019). Severe adverse events were reported in four patients (2.1%) with an overall transfusion-related lung injury rate of 1.56%. No CP-related deaths occurred. Discussion: CP is safe when used in patients with COVID-19 even when also presenting severity criteria or risk factors. Our mortality rate is comparable to reports from larger studies. Controlled clinical trials are required to determine efficacy.
Lung cancer frequency has been progressively increasing; this has been linked to the use of inhaled tobacco and air pollution. In Chile, air pollution has reached alarming levels due to motor vehicle traffic, firewood burning for heating and minerals in urban areas; for this reason, our objective was to evaluate the association between the incidence of lung cancer and the concentration of the main air pollutants monitored in the country. We carried out a cross-sectional ecological study that evaluated the association between the average incidence of lung cancer in a 5-year period (2015-2019) with the average annual concentration of six atmospheric pollutants in the 5 years prior in 14 Chilean boroughs, using the population of beneficiaries of the Fundación Arturo-López-Pérez Cancer Institute. The annualised incidence of lung cancer was 9.77 per 100,000 and it varied significantly within the boroughs studied. When evaluating the relationship between lungcancer incidence and the average concentration of atmospheric pollutants, we only found a direct and significant correlation between the level of respirable particulates 2.5 and the incidence of adenocarcinomas (β: 0.16; p: 0.023).
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