Acute pulmonary embolism as a complication in a young male patient with a left popliteal venous aneurysm

Abstract Venous aneurysms are rare and have a prevalence of 0.1 to 0.2% in the reported series. Typically, patients do not present any symptoms, but are prone to develop deep venous thrombosis (DVT) and the most feared complication, pulmonary embolism (PE). We present the case of a previously healthy 36-year-old man who presented at the emergency department with tachycardia, dyspnea, and pleuritic pain. A thoracic computed tomography angiography (CTA) confirmed the diagnosis of acute pulmonary embolism. He was treated with systemic thrombolysis and anticoagulation. In the further workup of the cause of the embolism, computed tomography revealed a fusiform dilation of the left popliteal vein measuring 3 by 3 centimeters (cm) with an incomplete filling defect because of thrombus presence. The patient underwent open surgical repair. At one month follow-up, he was asymptomatic, and an ultrasound revealed complete patency of the popliteal vein without dilatation or thrombus

The long-term safety, public health impact, and cost-effectiveness of routine vaccination with a recombinant, live-attenuated dengue vaccine (Dengvaxia): a model comparison study

This is the final version of the article. Available from the publisher via the DOI in this record.Background: Large Phase III trials across Asia and Latin America have recently demonstrated the efficacy of a recombinant, live-attenuated dengue vaccine (Dengvaxia) over the first 25 mo following vaccination. Subsequent data collected in the longer-term follow-up phase, however, have raised concerns about a potential increase in hospitalization risk of subsequent dengue infections, in particular among young, dengue-naïve vaccinees. We here report predictions from eight independent modelling groups on the long-term safety, public health impact, and cost-effectiveness of routine vaccination with Dengvaxia in a range of transmission settings, as characterised by seroprevalence levels among 9-y-olds (SP9). These predictions were conducted for the World Health Organization to inform their recommendations on optimal use of this vaccine. Methods and Findings: The models adopted, with small variations, a parsimonious vaccine mode of action that was able to reproduce quantitative features of the observed trial data. The adopted mode of action assumed that vaccination, similarly to natural infection, induces transient, heterologous protection and, further, establishes a long-lasting immunogenic memory, which determines disease severity of subsequent infections. The default vaccination policy considered was routine vaccination of 9-y-old children in a three-dose schedule at 80% coverage. The outcomes examined were the impact of vaccination on infections, symptomatic dengue, hospitalised dengue, deaths, and cost-effectiveness over a 30-y postvaccination period. Case definitions were chosen in accordance with the Phase III trials. All models predicted that in settings with moderate to high dengue endemicity (SP9 ≥ 50%), the default vaccination policy would reduce the burden of dengue disease for the population by 6%–25% (all simulations: –3%–34%) and in high-transmission settings (SP9 ≥ 70%) by 13%–25% (all simulations: 10%– 34%). These endemicity levels are representative of the participating sites in both Phase III trials. In contrast, in settings with low transmission intensity (SP9 ≤ 30%), the models predicted that vaccination could lead to a substantial increase in hospitalisation because of dengue. Modelling reduced vaccine coverage or the addition of catch-up campaigns showed that the impact of vaccination scaled approximately linearly with the number of people vaccinated. In assessing the optimal age of vaccination, we found that targeting older children could increase the net benefit of vaccination in settings with moderate transmission intensity (SP9 = 50%). Overall, vaccination was predicted to be potentially cost-effective in most endemic settings if priced competitively. The results are based on the assumption that the vaccine acts similarly to natural infection. This assumption is consistent with the available trial results but cannot be directly validated in the absence of additional data. Furthermore, uncertainties remain regarding the level of protection provided against disease versus infection and the rate at which vaccine-induced protection declines. Conclusions: Dengvaxia has the potential to reduce the burden of dengue disease in areas of moderate to high dengue endemicity. However, the potential risks of vaccination in areas with limited exposure to dengue as well as the local costs and benefits of routine vaccination are important considerations for the inclusion of Dengvaxia into existing immunisation programmes. These results were important inputs into WHO global policy for use of this licensed dengue vaccinSF and MJ received funding from WHO and Gavi, the Vaccine Alliance, to conduct this work. LC is a paid employee at Sanofi Pasteur. GM and JK were funded by the University of Western Australia, with computing resources provided by the Pawsey Supercomputing Centre, which is funded by the Australian Government and the Government of Western Australia. MR is funded by a Royal Society University Research Fellowship. NF, ID and DJL received research funding from the UK Medical Research Council, the UK NIHR under the Health Protection Research Unit initiative, NIGMS under the MIDAS initiative, and the Bill and Melinda Gates Foundation. IRB and DATC were funded by MIDAS Center Grant NIH/NIGMS U54-GM088491 and the Bill and Melinda Gates Foundation. DATC was also supported by NIH/NIAID R01-AI114703. TJH, IL, and CABP were funded by a Dengue Vaccine Initiative Grant to IL, NIH/NIAID R37 AI32042. THJ, IL, and KK were funded by MIDAS Center Grant NIH/NIGMS 1135 U54 GM111274. All other authors have received no specific funding to conduct this work. The funders had no role in the study design, data analyses, decision to publish or preparation of the manuscript

Impacts of urbanization on insect herbivory and plant defences in oak trees

Systematic comparisons of species interactions in urban versus rural environments can improve our understanding of shifts in ecological processes due to urbanization. However, such studies are relatively uncommon and the mechanisms driving urbanization effects on species interactions (e.g. between plants and insect herbivores) remain elusive. Here we investigated the effects of urbanization on leaf herbivory by insect chewers and miners associated with the English oak Quercus robur by sampling trees in rural and urban areas throughout most of the latitudinal distribution of this species. In performing these comparisons, we also controlled for the size of the urban areas (18 cities) and gathered data on CO emissions. In addition, we assessed whether urbanization affected leaf chemical defences (phenolic compounds) and nutritional traits (phosphorus and nitrogen), and whether such changes correlated with herbivory levels. Urbanization significantly reduced leaf chewer damage but did not affect leaf miners. In addition, we found that leaves from urban locations had lower levels of chemical defences (condensed and hydrolysable tannins) and higher levels of nutrients (nitrogen and phosphorus) compared to leaves in rural locations. The magnitude of urbanization effects on herbivory and leaf defences was not contingent upon city size. Importantly, while the effects of urbanization on chemical defences were associated with CO emissions, changes in leaf chewer damage were not associated with either leaf traits or CO levels. These results suggest that effects of urbanization on herbivory occur through mechanisms other than changes in the plant traits measured here. Overall, our simultaneous assessment of insect herbivory, plant traits and abiotic correlates advances our understanding of the main drivers of urbanization effects on plant–herbivore interactions.This research was financially supported by a Spanish National Research Grant (AGL2015-70748-R), a Regional Government of Galicia Grant (IN607D 2016/001) and the Ramón y Cajal Research Programme (RYC-2013-13230).Peer reviewe

Intra-specific latitudinal clines in leaf carbon, nitrogen, and phosphorus and their underlying abiotic correlates in Ruellia nudiflora

8 páginas, 1 figura y 1 tabla.While plant intra-specific variation in the stoichiometry of nutrients and carbon is well documented, clines for such traits have been less studied, despite their potential to reveal the mechanisms underlying such variation. Here we analyze latitudinal variation in the concentration of leaf nitrogen (N), phosphorus (P), carbon (C) and their ratios across 30 populations of the perennial herb Ruellia nudiflora. In addition, we further determined whether climatic and soil variables underlie any such latitudinal clines in leaf traits. The sampled transect spanned 5° latitude (ca. 900 km) and exhibited a four-fold precipitation gradient and 2 °C variation in mean annual temperature. We found that leaf P concentration increased with precipitation towards lower latitudes, whereas N and C did not exhibit latitudinal clines. In addition, N:P and C:P decreased towards lower latitudes and latitudinal variation in the former was weakly associated with soil conditions (clay content and cation exchange capacity); C:N did not exhibit a latitudinal gradient. Overall, these results emphasize the importance of addressing and disentangling the simultaneous effects of abiotic factors associated with intra-specific clines in plant stoichiometric traits, and highlight the previously underappreciated influence of abiotic factors on plant nutrients operating under sharp abiotic gradients over smaller spatial scales.This research was supported by a UC MEXUS-CONACyT collaborative grant (UCM-55592) to LAR, XM, KAM and VPT, a UC MEXUS grant for UC postdocs (UCM-101443), the Ramón y Cajal Research Program (RYC-2013-13230, a grant from the Regional Government of Galicia (IN607D 2016/001), and a Spanish National Research Grant (AGL2015-70748-R) to XM, as well as a grant from the i-COOP+ CSIC program (COOPB20158) to XM and LAR. LAR was also supported by the CONACyT Repatriation Program (#250934).Peer reviewe

Effects of seedling conspecific density and heterospecific frequency on insect herbivory in a tropical dry forest

9 páginas, 1 figura, 1 tablaConspecific plant density and heterospecific frequency are key drivers of herbivore damage. However, most studies have investigated their effects separately and for single (rather than multiple) focal plant species. We conducted an experiment involving three tree species, namely: Cordia dodecandra (Boraginaceae), Manilkara zapota (Zapotaceae), and Piscidia piscipula (Fabaceae). We manipulated understory densities of M. zapota and C. dodecandra (focal species) and their frequency relative to P. piscipula. Three months after planting, we surveyed insect leaf chewer and sucking damage on the former two. Because these species are attacked by different herbivores, we predicted a negative effect of heterospecific frequency on herbivory. Density and frequency varied in the direction and function of their effects on herbivory depending on the plant species and attacking herbivore. As expected, Piscidia piscipula frequency had a negative linear effect on M. zapota leaf-chewer damage, whereas conspecific density did not affect chewer damage on this species. In contrast, density and frequency had non-linear effects on C. dodecandra chewer damage, namely positive (hump-shaped) and negative (U-shaped) relationships, respectively. In addition, density and frequency had positive linear effects on C. dondecandra damage by leafhoppers. These findings call for more work jointly assessing plant inter-specific variation in density- and frequency-dependent variation in herbivory and its underlying drivers.Centro de Educación Ambiental de la Península de YucatánPeer reviewe

Subclavian-Brachial Bypass for Chronic Limb Threatening Ischemia Associated with an Old Motorcycle Accident

Chronic limb-threatening ischemia is rarely associated with previous traumatic injury. We present a case of a 28-year-old male with progressive digit ulcers, a weak pulse, cyanosis, and a cold limb. Eight months prior, he had a motorcycle accident resulting in a right clavicle fracture and brachial plexus injury. Computed tomography angiography revealed occlusion of the right subclavian artery near a surgically implanted reduction plate. The patient underwent an open subclavian-brachial bypass with a reversed saphenous vein graft. His postoperative recovery was uneventful. After 3 months, he had a euthermic right hand with a palpable pulse and his ulcers had completely healed. This case reinforces the need for patients with a neurological deficit in the upper extremity caused by blunt trauma to undergo thorough vascular examination to identify potential arterial injury and compromised perfusion