324 research outputs found
Reassessment of morphological siagnostic characters and species boundaries requires taxonomical changes for the genus Orthopyxis L. Agassiz, 1862 (Campanulariidae, Hydrozoa) and some related Campanulariids
The genus Orthopyxis is widely known for its morphological variability, making species identification particularly difficult. A number of nominal species have been recorded in the southwestern Atlantic, although most of these records are doubtful. The goal of this study was to infer species boundaries in the genus Orthopyxis from the southwestern Atlantic using an integrative approach. Intergeneric limits were also tested using comparisons with specimens of the genus Campanularia. We performed DNA analyses using the mitochondrial genes 16S and COI and the nuclear ITS1 and ITS2 regions. Orthopyxis was monophyletic in maximum likelihood analyses using the combined dataset and in analyses with 16S alone. Four lineages of Orthopyxis were retrieved for all analyses, corresponding morphologically to the species Orthopyxis sargassicola (previously known in the area), Orthopyxis crenata (first recorded for the southwestern Atlantic), Orthopyxis caliculata (= Orthopyxis minuta Vannucci, 1949 and considered a synonym of O. integra by some authors), and Orthopyxis mianzani sp. nov. A re-evaluation of the traditional morphological diagnostic characters, guided by our molecular analyses, revealed that O. integra does not occur in the study area, and O. caliculata is the correct identification of one of the lineages occurring in this region, corroborating the validity of that species. Orthopyxis mianzani sp. nov. resembles O. caliculata with respect to gonothecae morphology and a smooth hydrothecae rim, although it shows significant differences for other characters, such as perisarc thickness, which has traditionally been thought to have wide intraspecific variation. The species O. sargassicola is morphologically similar to O. crenata, although they differ in gonothecae morphology, and these species can only be reliably identified when this structure is present.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio (Capes)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) (grant no. 562143/2010-6; 563106/2010-7; 564945/2010-2; 477156/2011-8; 458555/2013-4; 305805/2013-4) (ACM)São Paulo Research Foudation (FAPESP) (grant no. 2004/ 09961-4; 2010/52324-6; 2011/50242-5; 2013/50484-4 – ACM, 2011/22260-9 – AFC),Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (grant no. PIP 0152 CONICET) (GNG
Longitudinal association of 25-Hydroxyvitamin D with adipokines and markers of glucose metabolism among Brazilian pregnant women
This study aimed to evaluate the longitudinal association of vitamin D status with glycaemia, insulin, Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), adiponectin and leptin. A prospective cohort with 181 healthy, pregnant Brazilian women was followed at the 5th–13th, 20th–26th, and 30th–36th gestational weeks. In this cohort, 25(OH)D plasma concentrations were analysed using liq¬uid chromatography-tandem mass spectrometry. Vitamin D status was categorized as sufficient or insufficient using the Endocrine Society Practice Guidelines (ES) (≥75/<75 nmol/L) and the Institute of Medicine (IOM) (≥50/<50 nmol/L) thresholds. Linear mixed-effect regression models were employed to evaluate the association between vitamin D status and each outcome, considering the interaction terms between vitamin D status and gestational age (P<0.1). At baseline, 70.7% of pregnant women had 25(OH)D levels <75 nmol/L and 16% had levels <50 nmol/L. Women with sufficient vitamin D status at baseline, using both the ES and IOM thresholds, presented lower glycaemia than those with insufficient 25(OH)D. Pregnant women with 25(OH)D concentrations <75 nmol/L showed lower insulin (β=-0.12; 95% CI -0.251, 0.009; P=0.069) and adiponectin (β=-0.070; 95% CI -0.150, 0.010; P=0.085) concentrations throughout pregnancy than those with 25(OH)D levels ≥75 nmol/L. Pregnant women with 25(OH)D <50 nmol/L at baseline presented significantly higher leptin concentrations than those with 25(OH)D levels ≥50 nmol/L (β=-0.253, 95% CI: -0.044; 0.550, P=0.095). The baseline status of vitamin D influences the biomarkers involved in glucose metabolism. Vitamin D sufficient women at baseline had higher increases of insulin and adiponectin changes throughout gestation than those who were insufficient
Case report: Diagnostic and therapeutic challenges of fungal endocarditis by Trichosporon asahii in a child with congenital heart defects
Backgroundpatients with congenital cardiopathies are the main group at risk for infective endocarditis (IE) in the pediatric population. Fungal etiology is responsible for 2%–4% of all IEs, and the Trichosporon genus is an increasingly prevalent cause of infections in human beings.Case presentationWe describe a 9-year-old male with multiple surgical procedures to correct congenital cardiopathy defects, including insertion of RV-PA conduit, who was admitted due to suspicion of pneumonia and needed a surgical approach after being diagnosed with a mycotic pseudoaneurysm in the right ventricle’s outflow tract, with dilation of the RV-PA conduit. The conduit was removed and antifungal treatment was started with Voriconazole after the agent was identified (T. asahii), with satisfactory therapeutic response. Approximately 4 years later, the patient was readmitted, presenting with intermittent fever, associated with nocturnal diaphoresis, dry cough, anxiety and chest pain. Vegetations consistent with T. asahii were evidenced in the RV-PA conduit, and a surgical approach was once again necessary.Discussiondiagnostic methods and treatment of T. asahii endocarditis aren't yet standardized, and recurrent surgical approaches are needed due to the inefficacy of antifungal treatment
Direct evidence for phosphorus limitation on Amazon forest productivity
The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.The authors acknowledge funding from the UK Natural Environment Research Council (NERC), grant number NE/L007223/1. This is publication 850 in the technical series of the BDFFP. C.A.Q. acknowledges the grants from Brazilian National Council for Scientific and Technological Development (CNPq) CNPq/LBA 68/2013, CNPq/MCTI/FNDCT no. 18/2021 and his productivity grant. C.A.Q., H.F.V.C., F.D.S., I.A., L.F.L., E.O.M. and S.G. acknowledge the AmazonFACE programme for financial support in cooperation with Coordination for the Improvement of Higher Education Personnel (CAPES) and the National Institute of Amazonian Research as part of the grants CAPES-INPA/88887.154643/2017-00 and 88881.154644/2017-01. T.F.D. acknowledges funds from FundacAo de Amparo a Pesquisa do Estado de SAo Paulo (FAPESP), grant 2015/50488-5, and the Partnership for Enhanced Engagement in Research (PEER) programme grant AID-OAA-A-11-00012. L.E.O.C.A. thanks CNPq (314416/2020-0)
Plant-made vaccines in support of the Millennium Development Goals
Vaccines are one of the most successful public health achievements of the last century. Systematic immunisation programs have reduced the burden of infectious diseases on a global scale. However, there are limitations to the current technology, which often requires costly infrastructure and long lead times for production. Furthermore, the requirement to keep vaccines within the cold-chain throughout manufacture, transport and storage is often impractical and prohibitively expensive in developing countries—the very regions where vaccines are most needed. In contrast, plant-made vaccines (PMVs) can be produced at a lower cost using basic greenhouse agricultural methods, and do not need to be kept within such narrow temperature ranges. This increases the feasibility of developing countries producing vaccines locally at a small-scale to target the specific needs of the region. Additionally, the ability of plant-production technologies to rapidly produce large quantities of strain-specific vaccine demonstrates their potential use in combating pandemics. PMVs are a proven technology that has the potential to play an important role in increasing global health, both in the context of the 2015 Millennium Development Goals and beyond
A Novel Neurotrophic Drug for Cognitive Enhancement and Alzheimer's Disease
Currently, the major drug discovery paradigm for neurodegenerative diseases is based upon high affinity ligands for single disease-specific targets. For Alzheimer's disease (AD), the focus is the amyloid beta peptide (Aß) that mediates familial Alzheimer's disease pathology. However, given that age is the greatest risk factor for AD, we explored an alternative drug discovery scheme that is based upon efficacy in multiple cell culture models of age-associated pathologies rather than exclusively amyloid metabolism. Using this approach, we identified an exceptionally potent, orally active, neurotrophic molecule that facilitates memory in normal rodents, and prevents the loss of synaptic proteins and cognitive decline in a transgenic AD mouse model
- …