18 research outputs found
Characterisation of myo-inositol hexakisphosphate deposits from larval Echinococcus granulosus
The abundant metabolite myo-inositol hexakisphosphate (InsP6) can form vesicular deposits with cations, a widespread phenomenon in plants also found in the cestode parasite, Echinococcus granulosus. In this organism, the deposits are exocytosed, accumulating in a host-exposed sheath of extracellular matrix termed the laminated layer. The formation and mobilization of InsP6 deposits, which involve precipitation and solubilization reactions, respectively, cannot yet be rationalized in quantitative chemical terms, as the solids involved have not been formally described. We report such a description for the InsP6 deposits from E. granulosus, purified as the solid residue left by mild alkaline digestion of the principal mucin component of the laminated layer. The deposits are largely composed of the compound Ca5H2L·16H2O (L representing fully deprotonated InsP6), and additionally contain Mg2+ (6â9% molar ratio with respect to Ca2+), but not K+. Calculations employing recently available chemical constants show that the precipitation of Ca5H2L·16H2O is predicted by thermodynamics in secretory vesicle-like conditions. The deposits appear to be similar to microcrystalline solids when analysed under the electron microscope; we estimate that each crystal comprises around 200 InsP6 molecules. We calculate that the deposits increase, by three orders of magnitude, the surface area available for adsorption of host proteins, a salient ability of the laminated layer. The major inositol phosphate in the deposits, other than InsP6, is myo-inositol (1,2,4,5,6) pentakisphosphate, or its enantiomer, inositol (2,3,4,5,6) pentakisphosphate. The compound appears to be a subproduct of the intracellular pathways leading to the synthesis and vesicular accumulation of InsP6, rather than arising from extracellular hydrolysis of InsP6
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Biogeosciences Perspectives on Integrated, Coordinated, Open, Networked (ICON) Science.
This article is composed of three independent commentaries about the state of Integrated, Coordinated, Open, Networked (ICON) principles in the American Geophysical Union Biogeosciences section, and discussion on the opportunities and challenges of adopting them. Each commentary focuses on a different topic: (a) Global collaboration, technology transfer, and application (Section 2), (b) Community engagement, community science, education, and stakeholder involvement (Section 3), and (c) Field, experimental, remote sensing, and real-time data research and application (Section 4). We discuss needs and strategies for implementing ICON and outline short- and long-term goals. The inclusion of global data and international community engagement are key to tackling grand challenges in biogeosciences. Although recent technological advances and growing open-access information across the world have enabled global collaborations to some extent, several barriers, ranging from technical to organizational to cultural, have remained in advancing interoperability and tangible scientific progress in biogeosciences. Overcoming these hurdles is necessary to address pressing large-scale research questions and applications in the biogeosciences, where ICON principles are essential. Here, we list several opportunities for ICON, including coordinated experimentation and field observations across global sites, that are ripe for implementation in biogeosciences as a means to scientific advancements and social progress
Tooth ankylosis in deciduous teeth of children with cleft lip and/or palate Anquilose dentĂĄria na dentição decĂdua em crianças com fissura de lĂĄbio e/ou palato
The present study aimed at evaluating the prevalence of tooth ankylosis in deciduous molars of Caucasian children with cleft lip and/or palate aged 5 to 12 years, of both genders. A total of 330 patients seen at the Hospital for Rehabilitation of Craniofacial Anomalies of the University of SĂŁo Paulo for routine treatment were clinically evaluated. The prevalence of ankylosis was analyzed in relation to gender, age range (5-7, 8-10, 11-12 years), type of cleft, affected tooth and arch. The total group showed a prevalence of 18%, with no statistical difference between genders and among types of cleft; ankylosis was more often in the mandibular arch, lower first molars and among children in the age ranges 8-10 and 11-12 years. The results agreed with those observed in the related literature for patients without clefts, pointing out the absence of influence of the cleft on the prevalence of ankylosis. This reinforces the importance of early diagnosis of this anomaly and of the treatment of choice, which are similar in patients with or without clefts.<br>Este estudo avaliou a prevalĂȘncia de anquilose dentĂĄria em molares decĂduos de portadores de fissura de lĂĄbio e/ou palato, brancos, de ambos os sexos, com idade entre 5 e 12 anos. Um total de 330 pacientes atendidos no Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de SĂŁo Paulo para tratamento de rotina foi clinicamente avaliado. A prevalĂȘncia de anquilose foi analisada em relação a gĂȘnero, idade (5-7; 8-10; 11-12 anos), tipo de fissura, dente e arco afetados. O grupo total demonstrou prevalĂȘncia de 18%, sem diferença estatĂstica entre gĂȘneros e tipos de fissura, sendo mais acometido o arco mandibular, o primeiro molar inferior e as faixas etĂĄrias de 8 a 10 e de 11 a 12 anos. Os resultados estĂŁo de acordo com aqueles observados na literatura para pacientes sem fissuras, destacando a ausĂȘncia da influĂȘncia das fissuras na prevalĂȘncia de anquilose. Isso reforça a importĂąncia do diagnĂłstico precoce dessa anomalia e do tratamento de escolha, que sĂŁo similares aos de pacientes sem fissuras