Interferência de Commelina benghalensis no crescimento inicial de Eucalyptus grandis no inverno e no verão

Eucalyptus seedlings are sensitive to the interference imposed by weed community, especially during the initial growth period, which is the first year after crop establishment. Thus, this study aimed at evaluating the effect of increasing densities of Commelina benghalensis L. on the initial growth of Eucalyptus grandis Hill (ex Maiden) plants at two seasons of the year. For this, two experiments were carried out using 70 L boxes in an open and semi-controlled area: one in winter (during 90 days) and another in summer (during 120 days). Both experiments were randomized block designs with four replicates each. The treatments consisted of increasing densities of tropical spiderwort, namely: 0 (control), 4, 8, 16, 20, 28, 36, 40, 60 and 80 plants m-2. Fifteen days after planting the tropical spiderwort seedlings, one seedling of eucalyptus was planted in the center of each box. The height, diameter, leaf area and total dry mass of eucalyptus were evaluated at the end of the experimental periods. Densities from 4 plants m-2 negatively interfered with eucalyptus growth, reducing by 38.4% the leaf area and 35% the dry mass in winter. While in summer, we found reductions of 52.9% in the leaf area and 64.7% in the dry mass. We concluded that the density from 4 plants m-2 interferes with the growth of eucalyptus and that the weed shows a more aggressive competitive behavior in the summer causing greater interference in the eucalyptus.Plantas de eucalipto são sensíveis à interferência imposta pela comunidade infestante, principalmente durante o crescimento inicial, período que compreende o primeiro ano após a instalação da cultura. Sendo assim, o presente estudo objetivou avaliar o efeito de densidades crescentes de Commelina benghalensis L. (trapoeraba) sobre o crescimento inicial de plantas de Eucalyptus grandis Hill (ex Maiden) em duas estações do ano (inverno e verão). Foram realizados dois experimentos, um no inverno (durante 90 dias) e outro no verão (durante 120 dias), em área aberta, semicontrolada, em caixas de 70 L. Para ambos os experimentos utilizou-se delineamento em blocos casualizados, com quatro repetições e os tratamentos consistiram de densidades crescentes de trapoeraba: 0 (testemunha), 4, 8, 16, 20, 28, 36, 40, 60 e 80 plantas m-2. Quinze dias após o plantio das mudas de trapoeraba, foi plantada uma muda de eucalipto no centro de cada caixa. Ao final dos períodos experimentais, foram avaliados a altura, o diâmetro, a área foliar e a massa seca da parte aérea do eucalipto. Observou-se que a partir de 4 plantas m-2 já houve interferência negativa no crescimento do eucalipto, com reduções de 38,4% na área foliar e 35% na massa seca, no inverno; e reduções de 52,9% na área foliar e 64,7% na massa seca, no período de verão. Conclui-se que a partir da densidade de 4 plantas m-2 há interferência no crescimento do eucalipto e que, no período de verão, a planta daninha apresenta comportamento competitivo mais agressivo, causando maior interferência nas plantas de eucalipto

Anti-angiogenic effects of pterogynidine alkaloid isolated from Alchornea glandulosa

<p>Abstract</p> <p>Background</p> <p>Angiogenesis, a complex multistep process that comprehends proliferation, migration and anastomosis of endothelial cells (EC), has a major role in the development of pathologic conditions such as inflammatory diseases, tumor growth and metastasis. Brazilian flora, the most diverse in the world, is an interesting spot to prospect for new chemical leads, being an important source of new anticancer drugs. Plant-derived alkaloids have traditionally been of interest due to their pronounced physiological activities. We investigated the anti-angiogenic potential of the naturally occurring guanidine alkaloid pterogynidine (Pt) isolated from the Brazilian plant <it>Alchornea glandulosa</it>. The purpose of this study was to examine which features of the angiogenic process could be disturbed by Pt.</p> <p>Methods</p> <p>Human umbilical vein endothelial cells (HUVEC) were incubated with 8 μM Pt and cell viability, proliferation, apoptosis, invasion and capillary-like structures formation were addressed. Nuclear factor κB (NFκB), a transcription factor implicated in these processes, was also evaluated in HUVEC incubated with Pt. Quantifications were expressed as mean ± SD of five independent experiments and one-way analysis of variance (ANOVA) followed by the Dunnet test was used.</p> <p>Results</p> <p>A significant decrease in proliferation and invasion capacity and an effective increase in apoptosis as assessed by bromodeoxyuridine (BrdU), double-chamber and terminal transferase dUTP nick end labeling (TUNEL) assay, respectively, have been found. Pt also led to a drastic reduction in the number of capillary-like structures formation when HUVEC were cultured on growth factor reduced-Matrigel (GFR-Matrigel) coated plates. In addition, incubation of HUVEC with Pt resulted in reduced NFκB activity.</p> <p>Conclusion</p> <p>These findings emphasize the potential use of Pt against pathological situations where angiogenesis is stimulated as tumor development.</p

Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure &lt;= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Diversity of helminth parasites of Colomesus psittacus on the Soure Marine Extractives Reserve in the Brazilian Amazon

The objective of this study was to record the parasitic fauna of Colomesus psittacus from Marajó Island, State of Pará, in the Brazilian Amazon. The fish were necropsied, and their organs were individualized in a petri dish to search for helminths using a stereomicroscope. These helminths were then clarified and identified. Of the 50 specimens examined, 76% were parasitized by one or more species, and a total of 807 parasites were recovered. Among the helminths, it was possible to identify five nematodes (Huffmanela psittacus (70%), Anisakis sp. (12%), Hysterothylacium sp. (8%), Philometra sp. 1 (28%), Philometra sp. 2 (2%), Cucullanus marajoara (28%), Cucullanus sp. L3 (34%), a trematode Bianium sp. (2%), and two parasites belonging to the phylum Acanthocephala. The helminth community in C. psittacus was characterized by a high richness of nematodes and a small number of digenetics and acanthocephala. Thus, this is a new record of parasitic fauna in C. psittacus in Brazil

Increasing the efficiency of conventional LFR technologies: A new CLFR "Etendue-Matched" CSP collector

Solar concentrating technologies are seen as an important part of the strategy to increase the production of both renewable electricity and heat. Several technologies have been proved to be technically feasible; commercially Parabolic Through systems (PTR) have been in the lead in installed capacity in new power plants. One promising technology that has a lower investment cost per m2 is the LFR, Linear Fresnel Reflector collector. First demonstration plants in Spain and in the USA, are proving the concept technically, but failing yet to be a generalized choice, since their global efficiency conversion is still low. CLFR technology said to be “Étendue Matched” and designed to take full advantage of ideal non-imaging optics is a very promising alternative. In fact, through a joint optimization of primary and secondary stages of concentration, it is possible to find an answer to this problem, practically doubling the achieved concentration in conventional LFR configurations, substantially reducing optical losses due to shading and blocking and taking advantage of a multi-receiver design (that is what the “C” stands for). The present paper explains the concept and describes the prototype being proposed for demonstration

Ozolaimus megatyphlon and Ozolaimus cirratus parasitizing the Iguana iguana (Linnaeus, 1758) from Marajó Island, Pará, Brasil: new occurrence and morphological redescription

Abstract This study aimed to redescribe two species of Ozolaimus, parasites of free-living green iguanas native to Marajó Island. The gastrointestinal system of four iguana specimens was evaluated for the presence of helminths. Altogether, 12,028 nematodes were found, with a prevalence of 100%, an infection range of 780 to 7,736 nematodes, an infection intensity of 3.007, and a mean abundance of 3,007. Light microscopy and scanning electron microscopy were used to determine the species of nematodes found. The cecum was the site of infection that had the highest parasitic load. Morphologically, the nematodes were compatible with the genus Ozolaimus Dujardin, 1844, with the species Ozolaimus megatyphlon (Rudolphi, 1819) Dujardin, 1845, and Ozolaimus cirratus Linstow, 1906. Scanning electron microscopy showed the presence of small structures (serrated in Ozolaimus cirratus and rounded in Ozolaimus megatyphlon) located below the esophageal leaves. We also evidenced the phasmids in both species; this is the first record of these structures in nematodes of the genus Ozolaimus. In addition, this work expands the records on the geographic distribution of these parasites