129 research outputs found

    Will all scientists working on snails and the diseases they transmit please stand up?

    Get PDF
    Copyright © 2012 Adema et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.No abstract available

    A Somatically Diversified Defense Factor, FREP3, Is a Determinant of Snail Resistance to Schistosome Infection

    Get PDF
    Schistosomiasis, a neglected tropical disease, owes its continued success to freshwater snails that support production of prolific numbers of human-infective cercariae. Encounters between schistosomes and snails do not always result in the snail becoming infected, in part because snails can mount immune responses that prevent schistosome development. Fibrinogen-related protein 3 (FREP3) has been previously associated with snail defense against digenetic trematode infection. It is a member of a large family of immune molecules with a unique structure consisting of one or two immunoglobulin superfamily domains connected to a fibrinogen domain; to date fibrinogen containing proteins with this arrangement are found only in gastropod molluscs. Furthermore, specific gastropod FREPs have been shown to undergo somatic diversification. Here we demonstrate that siRNA mediated knockdown of FREP3 results in a phenotypic loss of resistance to Schistosoma mansoni infection in 15 of 70 (21.4%) snails of the resistant BS-90 strain of Biomphalaria glabrata. In contrast, none of the 64 control BS-90 snails receiving a GFP siRNA construct and then exposed to S. mansoni became infected. Furthermore, resistance to S. mansoni was overcome in 22 of 48 snails (46%) by pre-exposure to another digenetic trematode, Echinostoma paraensei. Loss of resistance in this case was shown by microarray analysis to be associated with strong down-regulation of FREP3, and other candidate immune molecules. Although many factors are certainly involved in snail defense from trematode infection, this study identifies for the first time the involvement of a specific snail gene, FREP3, in the phenotype of resistance to the medically important parasite, S. mansoni. The results have implications for revealing the underlying mechanisms involved in dictating the range of snail strains used by S. mansoni, and, more generally, for better understanding the phenomena of host specificity and host switching. It also highlights the role of a diversified invertebrate immune molecule in defense against a human pathogen. It suggests new lines of investigation for understanding how susceptibility of snails in areas endemic for S. mansoni could be manipulated and diminished

    Effects of Genetic Variants in ADCY5, GIPR, GCKR and VPS13C on Early Impairment of Glucose and Insulin Metabolism in Children

    Get PDF
    OBJECTIVE: Recent genome-wide association studies identified novel candidate genes for fasting and 2 h blood glucose and insulin levels in adults. We investigated the role of four of these loci (ADCY5, GIPR, GCKR and VPS13C) in early impairment of glucose and insulin metabolism in children. RESEARCH DESIGN AND METHODS: We genotyped four variants (rs2877716; rs1260326; rs10423928; rs17271305) in 638 Caucasian children with detailed metabolic testing including an oGTT and assessed associations with measures of glucose and insulin metabolism (including fasting blood glucose, insulin levels and insulin sensitivity/secretion indices) by linear regression analyses adjusted for age, sex, BMI-SDS and pubertal stage. RESULTS: The major allele (C) of rs2877716 (ADCY5) was nominally associated with decreased fasting plasma insulin (P = 0.008), peak insulin (P = 0.009) and increased QUICKI (P = 0.016) and Matsuda insulin sensitivity index (P = 0.013). rs17271305 (VPS13C) was nominally associated with 2 h blood glucose (P = 0.009), but not with any of the insulin or insulin sensitivity parameters. We found no association of the GIPR and GCKR variants with parameters of glucose and insulin metabolism. None of the variants correlated with anthropometric traits such as height, WHR or BMI-SDS, which excluded potential underlying associations with obesity. CONCLUSIONS: Our data on obese children indicate effects of genetic variation within ADCY5 in early impairment of insulin metabolism and VPS13C in early impairment of blood glucose homeostasis

    Outcomes after urgent thyroidectomy following rapid control of thyrotoxicosis in Graves’ disease are similar to those after elective surgery in well-controlled disease

    Get PDF
    Background Surgery for Graves’ disease (GD) is usually performed after adequate control with medical treatment. Occasionally, rapid pre-operative optimization is required. The primary objective was to compare the outcomes of patients undergoing elective surgery for well-controlled GD with those undergoing rapid pre-operative treatment. We also propose a formal treatment protocol for future use. Methods A retrospective cohort study in a tertiary referral centre included 247 patients with well-controlled GD undergoing elective surgery and 19 patients with poorly controlled disease undergoing surgery after rapid optimization. The latter group did not respond well to thionamides (carbimazole and/or propylthiouracil) or had intolerance or side effects to thionamides and were treated with a range of non-thionamide drugs, including Lugol’s iodine, cholestyramine, beta blockers and steroids (with or without thionamides), and closely monitored for 1–2 weeks before surgery. Outcome measures included thyroid storm, hypoparathyroidism and recurrent laryngeal nerve palsy. Results In total, 266 patients with male-to-female ratio of 1:6 and median (interquartile range) age of 39 (31–51) were included. Overall, long-term recurrent laryngeal palsy and hypoparathyroidism occurred in 1 (0.38%) and 13 (4.9%) patients, respectively. No patient had thyroid storm. There was no significant difference in hypoparathyroidism (p = 1), vocal cord palsy (p = 0.803) and post-operative bleeding (p = 0.362), between elective surgery and rapid optimization groups. Conclusion Rapid pre-operative treatment is effective, safe and is associated with similar outcomes compared to usual treatment. A rapid pre-operative optimization protocol is proposed

    Interactive models of communication at the nanoscale using nanoparticles that talk to one another

    Full text link
    [EN] 'Communication' between abiotic nanoscale chemical systems is an almost-unexplored field with enormous potential. Here we show the design and preparation of a chemical communication system based on enzyme-powered Janus nanoparticles, which mimics an interactive model of communication. Cargo delivery from one nanoparticle is governed by the biunivocal communication with another nanoparticle, which involves two enzymatic processes and the interchange of chemical messengers. The conceptual idea of establishing communication between nanodevices opens the opportunity to develop complex nanoscale systems capable of sharing information and cooperating.A. L.-L. is grateful to 'La Caixa' Banking Foundation for his PhD fellowship. We wish to thank the Spanish Government (MINECO Projects MAT2015-64139-C4-1, CTQ2014-58989-P and CTQ2015-71936-REDT and AGL2015-70235-C2-2-R) and the Generalitat Valenciana (Project PROMETEOII/2014/047) for support. The Comunidad de Madrid (S2013/MIT-3029, Programme NANOAVANSENS) is also gratefully acknowledged.Llopis-Lorente, A.; Díez, P.; Sánchez, A.; Marcos Martínez, MD.; Sancenón Galarza, F.; Martínez-Ruiz, P.; Villalonga, R.... (2017). Interactive models of communication at the nanoscale using nanoparticles that talk to one another. Nature Communications. 8:1-7. https://doi.org/10.1038/ncomms15511S178Tseng, R., Huang, J., Ouyang, J., Kaner, R. & Yang, Y. Polyaniline nanofiber/gold nanoparticle nonvolatile memory. Nano Lett. 5, 1077–1080 (2005).Liu, R. & Sen, A. Autonomous nanomotor based on copper-platinum segmented nanobattery. J. Am. Chem. Soc. 133, 20064–20067 (2011).Valov, I. et al. Nanobatteries in redox-based resistive switches require extension of memristor theory. Nat. Commun. 4, 1771 (2013).Tarn, D. et al. Mesoporous silica nanoparticle nanocarriers: biofunctionality and biocompatibility. Acc. Chem. Res. 46, 792–801 (2013).Kline, T. & Paxton, W. Catalytic nanomotors: remote-controlled autonomous movement of striped metallic nanorods. Angew. Chem. Int. Ed. 117, 754–756 (2005).Akyildiz, I. F., Brunetti, F. & Blázquez, C. Nanonetworks: a new communication paradigm. Comput. Netw. 52, 2260–2279 (2008).Suda, T., Moore, M., Nakano, T., Egashira, R. & Enomoto, A. Exploratory research on molecular communication between nanomachines. Nat. Comput. 25, 1–30 (2005).Malak, D. & Akan, O. B. Molecular communication nanonetworks inside human body. Nano Commun. Netw. 3, 19–35 (2012).Akyildiz, I. F., Jornet, J. M. & Pierobon, M. Nanonetworks: a new frontier in communications. Commun. ACM 54, 84–89 (2011).Nakano, T., Moore, M. J., Wei, F., Vasilakos, A. V. & Shuai, J. Molecular communication and networking: opportunities and challenges. IEEE Trans. Nanobiosci. 11, 135–148 (2012).Waters, C. M. & Bassler, B. L. Quorum sensing: cell-to-cell communication in bacteria. Annu. Rev. Cell Dev. Biol. 21, 319–346 (2005).Dickschat, J. S. Quorum sensing and bacterial biofilms. Nat. Prod. Rep. 27, 343–369 (2010).Kerényi, Á., Bihary, D., Venturi, V. & Pongor, S. Stability of multispecies bacterial communities: signaling networks may stabilize microbiomes. PLoS ONE 8, e57947 (2013).Gotti, C. & Clementi, F. Neuronal nicotinic receptors: from structure to pathology. Prog. Neurobiol. 74, 363–396 (2004).Betke, K. M., Wells, C. A. & Hamm, H. E. GPCR mediated regulation of synaptic transmission. Prog. Neurobiol. 96, 304–321 (2012).Qian, L., Winfree, E. & Bruck, J. Neural network computation with DNA strand displacement cascades. Nature 475, 368–372 (2011).Benenson, Y. Biomolecular computing systems: principles, progress and potential. Nat. Rev. Genet. 13, 455–468 (2012).Ball, P. Chemistry meets computing. Nature 406, 118–120 (2000).de Silva, A. P. & McClenaghan, N. D. Molecular-Scale Logic Gates. Chem. Eur. J. 10, 574–586 (2004).Condon, A. Automata make antisense. Nature 429, 351–352 (2004).Seelig, G., Soloveichik, D., Zhang, D. Y. & Winfree, E. Enzyme-free nucleic acid logic circuits. Science 314, 1585–1588 (2006).Douglas, S. M., Bachelet, I. & Church, G. M. A logic-gated nanorobot for targeted transport of molecular payloads. Science 335, 831–834 (2012).Angelos, S., Yang, Y. W., Khashab, N. M., Stoddart, J. F. & Zink, J. I. Dual-controlled nanoparticles exhibiting AND logic. J. Am. Chem. Soc. 131, 11344–11346 (2009).Liu, H. et al. Dual-responsive surfaces modified with phenylboronic acid-containing polymer brush to reversibly capture and release cancer cells. J. Am. Chem. Soc. 135, 7603–7609 (2013).Lee, J. W. & Klajn, R. Dual-responsive nanoparticles that aggregate under the simultaneous action of light and CO2 . Chem. Commun. 51, 2036–2039 (2015).Liu, D. et al. Resettable, multi-readout logic gates based on controllably reversible aggregation of gold nanoparticles. Angew. Chem. Int. Ed. 50, 4103–4107 (2011).Chitode, J. S. Communication Theory Technical Publications (2010).Wood, J. T. Communication in Our Lives Wadsworth (2009).Guardado-Alvarez, T. M., Sudha Devi, L., Russell, M. M., Schwartz, B. J. & Zink, J. I. Activation of snap-top capped mesoporous silica nanocontainers using two near-infrared photons. J. Am. Chem. Soc. 135, 14000–14003 (2013).Baeza, A., Guisasola, E., Ruiz-Hernández, E. & Vallet-Regí, M. Magnetically triggered multidrug release by hybrid mesoporous silica nanoparticles. Chem. Mater. 24, 517–524 (2012).Zhang, Z. et al. Biocatalytic release of an anticancer drug from nucleic-acids-capped mesoporous SiO2 using DNA or molecular biomarkers as triggering stimuli. ACS Nano 7, 8455–8468 (2013).Tang, F., Li, L. & Chen, D. Mesoporous silica nanoparticles: synthesis, biocompatibility and drug delivery. Adv. Mater. 24, 1504–1534 (2012).Li, Z., Barnes, J. C., Bosoy, A., Stoddart, J. F. & Zink, J. I. Mesoporous silica nanoparticles in biomedical applications. Chem. Soc. Rev. 41, 2590–2605 (2012).Coll, C., Bernardos, A., Martínez-Máñez, R. & Sancenón, F. Gated silica mesoporous supports for controlled release and signaling applications. Acc. Chem. Res. 46, 339–349 (2013).Aznar, E. et al. Gated materials for on-command release of guest molecules. Chem. Rev. 116, 561–718 (2016).Díez, P. et al. Toward the design of smart delivery systems controlled by integrated enzyme-based biocomputing ensembles. J. Am. Chem. Soc. 136, 9116–9123 (2014).Villalonga, R. et al. Enzyme-controlled sensing-actuating nanomachine based on Janus Au-mesoporous silica nanoparticles. Chem. Eur. J. 19, 7889–7894 (2013).Jerez, G., Kaufman, G., Prystai, M., Schenkeveld, S. & Donkor, K. K. Determination of thermodynamic pKa values of benzimidazole and benzimidazole derivatives by capillary electrophoresis. J. Sep. Sci. 32, 1087–1095 (2009).Sheffner, A. L. The reduction in vitro in viscosity of mucoprotein solutions by a new mucolytic agent, N-acetyl-L-cysteine. Ann. N. Y. Acad. Sci. 106, 298–310 (1963).Turkevich, J., Stevenson, P. C. & Hillier, J. A study of the nucleation and growth processes in the synthesis of colloidal gold. Discuss. Faraday Soc. 11, 55–75 (1951).Frens, G. Controlled Nucleation for the Regulation of the Particle Size in Monodisperse Gold Suspensions. Nature 241, 20–22 (1973).Yousef, F. O., Zughul, M. B. & Badwan, A. A. The modes of complexation of benzimidazole with aqueous β-cyclodextrin explored by phase solubility, potentiometric titration, 1H-NMR and molecular modeling studies. J. Incl. Phenom. Macrocycl. Chem. 57, 519–523 (2007).Sánchez, A., Díez, P., Martínez-Ruíz, P., Villalonga, R. & Pingarrón, J. M. Janus Au-mesoporous silica nanoparticles as electrochemical biorecognition-signaling system. Electrochem. Commun. 30, 51–54 (2013).Akyildiz, I. F., Pierobon, M., Balasubramaniam, S. & Koucheryavy, Y. The internet of Bio-Nano things. IEEE Commun. Mag. 53, 32–40 (2015).Sancenón, F., Pascual, L., Oroval, M., Aznar, E. & Martínez-Máñez, R. Gated silica mesoporous materials in sensing applications. ChemistryOpen 4, 418–437 (2015).Akyildiz, I. & Jornet, J. The Internet of nano-things. IEEE Wirel. Commun. 17, 58–63 (2010).Giménez, C. et al. Towards chemical communication between gated nanoparticles. Angew. Chem. Int. Ed. 53, 12629–12633 (2014).Davis, B. G., Lloyd, R. C. & Jones, J. B. Controlled site-selective glycosylation of proteins by a combined site-directed mutagenesis and chemical modification approach. J. Org. Chem. 63, 9614–9615 (1998)

    Neuroanatomical heterogeneity and homogeneity in individuals at clinical high risk for psychosis

    Full text link
    Individuals at Clinical High Risk for Psychosis (CHR-P) demonstrate heterogeneity in clinical profiles and outcome features. However, the extent of neuroanatomical heterogeneity in the CHR-P state is largely undetermined. We aimed to quantify the neuroanatomical heterogeneity in structural magnetic resonance imaging measures of cortical surface area (SA), cortical thickness (CT), subcortical volume (SV), and intracranial volume (ICV) in CHR-P individuals compared with healthy controls (HC), and in relation to subsequent transition to a first episode of psychosis. The ENIGMA CHR-P consortium applied a harmonised analysis to neuroimaging data across 29 international sites, including 1579 CHR-P individuals and 1243 HC, offering the largest pooled CHR-P neuroimaging dataset to date. Regional heterogeneity was indexed with the Variability Ratio (VR) and Coefficient of Variation (CV) ratio applied at the group level. Personalised estimates of heterogeneity of SA, CT and SV brain profiles were indexed with the novel Person-Based Similarity Index (PBSI), with two complementary applications. First, to assess the extent of within-diagnosis similarity or divergence of neuroanatomical profiles between individuals. Second, using a normative modelling approach, to assess the 'normativeness' of neuroanatomical profiles in individuals at CHR-P. CHR-P individuals demonstrated no greater regional heterogeneity after applying FDR corrections. However, PBSI scores indicated significantly greater neuroanatomical divergence in global SA, CT and SV profiles in CHR-P individuals compared with HC. Normative PBSI analysis identified 11 CHR-P individuals (0.70%) with marked deviation (>1.5?SD) in SA, 118 (7.47%) in CT and 161 (10.20%) in SV. Psychosis transition was not significantly associated with any measure of heterogeneity. Overall, our examination of neuroanatomical heterogeneity within the CHR-P state indicated greater divergence in neuroanatomical profiles at an individual level, irrespective of psychosis conversion. Further large-scale investigations are required of those who demonstrate marked deviation.© 2022. The Author(s)

    Structure of a Murine Norovirus NS6 Protease-Product Complex Revealed by Adventitious Crystallisation

    Get PDF
    Murine noroviruses have emerged as a valuable tool for investigating the molecular basis of infection and pathogenesis of the closely related human noroviruses, which are the major cause of non-bacterial gastroenteritis. The replication of noroviruses relies on the proteolytic processing of a large polyprotein precursor into six non-structural proteins (NS1–2, NS3, NS4, NS5, NS6pro, NS7pol) by the virally-encoded NS6 protease. We report here the crystal structure of MNV NS6pro, which has been determined to a resolution of 1.6 Å. Adventitiously, the crystal contacts are mediated in part by the binding of the C-terminus of NS6pro within the peptide-binding cleft of a neighbouring molecule. This insertion occurs for both molecules in the asymmetric unit of the crystal in a manner that is consistent with physiologically-relevant binding, thereby providing two independent views of a protease-peptide complex. Since the NS6pro C-terminus is formed in vivo by NS6pro processing, these crystal contacts replicate the protease-product complex that is formed immediately following cleavage of the peptide bond at the NS6-NS7 junction. The observed mode of binding of the C-terminal product peptide yields new insights into the structural basis of NS6pro specificity

    Frequent loss of the AXIN1 locus but absence of AXIN1 gene mutations in adenocarcinomas of the gastro-oesophageal junction with nuclear β-catenin expression

    Get PDF
    Up to 60% of gastro-oesophageal junction (GEJ) adenocarcinomas show nuclear β-catenin expression, pointing to activated T-cell factor (TCF)/β-catenin-driven gene transcription. We demonstrate in five human GEJ adenocarcinoma cell lines that nuclear β-catenin expression indeed correlates with enhanced TCF-mediated transcription of a reporter gene. In several tumour types, TCF/β-catenin activation is caused by mutations in either adenomatous polyposis coli (APC), β-catenin exon 3, AXIN1, AXIN2 or β-transducin repeat-containing protein (β-TrCP). In GEJ adenocarcinomas, very few APC and β-catenin mutations have been found. Therefore, the mechanism of Wnt pathway activation remains unclear. In the present study, we did not find AXIN1 gene mutations in 17 GEJ tumours with nuclear β-catenin expression (without β-catenin exon 3 mutations). Six intragenic single nucleotide polymorphisms (SNPs) were identified. One of these, the AXIN1 gene T1942C SNP, has a frequency of 21% but is only very recently described despite numerous AXIN1 gene mutational studies. We provide evidence why this SNP was missed in single strand conformation polymorphism analyses. The AXIN1 gene G2063A variation was previously described as a gene mutation but we demonstrate that this is a polymorphism. With these six SNPs loss of heterozygosity (LOH) was found in 11 of 15 (73%) informative tumours. To investigate a possible AXIN1 gene dosage effect in GEJ tumours expressing nuclear β-catenin, AXIN1 locus LOH was determined in 20 tumours expressing membranous and no nuclear β-catenin. LOH was found in 10 of 13 (77%) informative cases. AXIN1 protein immunohistochemistry revealed cytoplasmic expression in all tumours irrespective of the presence of AXIN1 locus LOH. These data indicate that nuclear β-catenin expression is indicative for activated Wnt signalling and that neither AXIN1 gene mutations nor AXIN1 locus LOH are involved in Wnt pathway activation in GEJ adenocarcinomas

    Fires can benefit plants by disrupting antagonistic interactions

    Get PDF
    Fire has a key role in the ecology and evolution of many ecosystems, yet its effects on plant–insect interactions are poorly understood. Because interacting species are likely to respond to fire differently, disruptions of the interactions are expected. We hypothesized that plants that regenerate after fire can benefit through the disruption of their antagonistic interactions. We expected stronger effects on interactions with specialist predators than with generalists. We studied two interactions between two Mediterranean plants (Ulex parviflorus, Asphodelus ramosus) and their specialist seed predators after large wildfires. In A. ramosus we also studied the generalist herbivores. We sampled the interactions in burned and adjacent unburned areas during 2 years by estimating seed predation, number of herbivores and fruit set. To assess the effect of the distance to unburned vegetation we sampled plots at two distance classes from the fire perimeter. Even 3 years after the fires, Ulex plants experienced lower seed damage by specialists in burned sites. The presence of herbivores on Asphodelus decreased in burned locations, and the variability in their presence was significantly related to fruit set. Generalist herbivores were unaffected. We show that plants can benefit from fire through the disruption of their antagonistic interactions with specialist seed predators for at least a few years. In environments with a long fire history, this effect might be one additional mechanism underlying the success of fire-adapted plants

    Integral strategy to supportive care in breast cancer survivors through occupational therapy and a m-health system: design of a randomized clinical trial

    Get PDF
    Background: Technological support using e-health mobile applications (m-health) is a promising strategy to improve the adherence to healthy lifestyles in breast cancer survivors (excess in energy intake or low physical activity are determinants of the risk of recurrence, second cancers and cancer mortality). Moreover, cancer rehabilitation programs supervised by health professionals are needed due to the inherent characteristics of these breast cancer patients. Our main objective is to compare the clinical efficacy of a m-health lifestyle intervention system alone versus an integral strategy to improve Quality of Life in breast cancer survivors. Methods: This therapeutic superiority study will use a two-arm, assessor blinded parallel RCT design. Women will be eligible if: they are diagnosed of stage I, II or III-A breast cancer; are between 25 and 75 years old; have a Body Mass Index > 25 kg/m2; they have basic ability to use mobile apps; they had completed adjuvant therapy except for hormone therapy; and they have some functional shoulder limitations. Participants will be randomized to one of the following groups: integral group will use a mobile application (BENECA APP) and will receive a face-to-face rehabilitation (8-weeks); m-health group will use the BENECA app for 2-months and will received usual care information. Study endpoints will be assessed after 8 weeks and 6 months. The primary outcome will be Quality of Life measured by The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core and breast module. The secondary outcomes: body composition; upper-body functionality (handgrip, Disability of the Arm, Shoulder and Hand questionnaire, goniometry); cognitive function (Wechsler Adult Intelligence Scale, Trail Making Test); anxiety and depression (Hospital Anxiety and Depression Scale); physical fitness (Short version of the Minnesota Leisure Time Physical Activity Questionnaire, Self-Efficacy Scale for Physical Activity); accelerometry and lymphedema. Discussion: This study has been designed to seek to address the new needs for support and treatment of breast cancer survivors, reflecting the emerging need to merge new low cost treatment options with much-needed involvement of health professionals in this type of patients. Trial registration: ClinicalTrials.gov Identifier: NCT02817724 (date of registration: 22/06/2016).The study was funded by the Spanish Ministry of Economy and Competitiveness (Plan Estatal de I + D + I 2013-2016), Fondo de Investigación Sanitaria del Instituto de Salud Carlos III (PI14/01627), Fondos Estructurales de la Unión Europea (FEDER) and by the Spanish Ministry of Education (FPU14/01069). This is part of a Ph.D. Thesis conducted in the Clinical Medicine and Public Health Doctoral Studies of the University of Granada, Spain
    corecore