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1.
Mol Biol Evol ; 39(4)2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35277960

RESUMEN

Neuropeptides are a diverse class of signaling molecules in metazoans. They occur in all animals with a nervous system and also in neuron-less placozoans. However, their origin has remained unclear because no neuropeptide shows deep homology across lineages, and none have been found in sponges. Here, we identify two neuropeptide precursors, phoenixin (PNX) and nesfatin, with broad evolutionary conservation. By database searches, sequence alignments, and gene-structure comparisons, we show that both precursors are present in bilaterians, cnidarians, ctenophores, and sponges. We also found PNX and a secreted nesfatin precursor homolog in the choanoflagellate Salpingoeca rosetta. PNX, in particular, is highly conserved, including its cleavage sites, suggesting that prohormone processing occurs also in choanoflagellates. In addition, based on phyletic patterns and negative pharmacological assays, we question the originally proposed GPR-173 (SREB3) as a PNX receptor. Our findings revealed that secreted neuropeptide homologs derived from longer precursors have premetazoan origins and thus evolved before neurons.


Asunto(s)
Coanoflagelados , Ctenóforos , Neuropéptidos , Animales , Evolución Biológica , Coanoflagelados/genética , Sistema Nervioso , Neuropéptidos/genética
2.
Mol Biol Evol ; 38(11): 4847-4866, 2021 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-34272863

RESUMEN

Neuropeptides are diverse signaling molecules in animals commonly acting through G-protein coupled receptors (GPCRs). Neuropeptides and their receptors underwent extensive diversification in bilaterians and the relationships of many peptide-receptor systems have been clarified. However, we lack a detailed picture of neuropeptide evolution in lophotrochozoans as in-depth studies only exist for mollusks and annelids. Here, we analyze peptidergic systems in Nemertea, Brachiopoda, and Phoronida. We screened transcriptomes from 13 nemertean, 6 brachiopod, and 4 phoronid species for proneuropeptides and neuropeptide GPCRs. With mass spectrometry from the nemertean Lineus longissimus, we validated several predicted peptides and identified novel ones. Molecular phylogeny combined with peptide-sequence and gene-structure comparisons allowed us to comprehensively map spiralian neuropeptide evolution. We found most mollusk and annelid peptidergic systems also in nemerteans, brachiopods, and phoronids. We uncovered previously hidden relationships including the orthologies of spiralian CCWamides to arthropod agatoxin-like peptides and of mollusk APGWamides to RGWamides from annelids, with ortholog systems in nemerteans, brachiopods, and phoronids. We found that pleurin neuropeptides previously only found in mollusks are also present in nemerteans and brachiopods. We also identified cases of gene family duplications and losses. These include a protostome-specific expansion of RFamide/Wamide signaling, a spiralian expansion of GnRH-related peptides, and duplications of vasopressin/oxytocin before the divergence of brachiopods, phoronids, and nemerteans. This analysis expands our knowledge of peptidergic signaling in spiralians and other protostomes. Our annotated data set of nearly 1,300 proneuropeptide sequences and 600 GPCRs presents a useful resource for further studies of neuropeptide signaling.


Asunto(s)
Invertebrados , Transducción de Señal , Secuencia de Aminoácidos , Animales , Invertebrados/genética , Filogenia , Receptores Acoplados a Proteínas G/genética
3.
PLoS Biol ; 17(7): e3000408, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31356592

RESUMEN

Most bilaterian animals excrete toxic metabolites through specialized organs, such as nephridia and kidneys, which share morphological and functional correspondences. In contrast, excretion in non-nephrozoans is largely unknown, and therefore the reconstruction of ancestral excretory mechanisms is problematic. Here, we investigated the excretory mode of members of the Xenacoelomorpha, the sister group to Nephrozoa, and Cnidaria, the sister group to Bilateria. By combining gene expression, inhibitor experiments, and exposure to varying environmental ammonia conditions, we show that both Xenacoelomorpha and Cnidaria are able to excrete across digestive-associated tissues. However, although the cnidarian Nematostella vectensis seems to use diffusion as its main excretory mode, the two xenacoelomorphs use both active transport and diffusion mechanisms. Based on these results, we propose that digestive-associated tissues functioned as excretory sites before the evolution of specialized organs in nephrozoans. We conclude that the emergence of a compact, multiple-layered bilaterian body plan necessitated the evolution of active transport mechanisms, which were later recruited into the specialized excretory organs.


Asunto(s)
Cnidarios/genética , Digestión/genética , Sistema Digestivo/metabolismo , Eliminación Intestinal/genética , Neoptera/genética , Amoníaco/metabolismo , Animales , Transporte Biológico/genética , Cnidarios/clasificación , Cnidarios/metabolismo , Difusión , Digestión/fisiología , Sistema Digestivo/anatomía & histología , Regulación de la Expresión Génica , Eliminación Intestinal/fisiología , Neoptera/clasificación , Neoptera/metabolismo , Filogenia
4.
Dev Biol ; 434(1): 15-23, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29197505

RESUMEN

In situ hybridization is a widely employed technique allowing spatial visualization of gene expression in fixed specimens. It has greatly advanced our understanding of biological processes, including developmental regulation. In situ protocols are today routinely followed in numerous laboratories, and although details might change, they all include a hybridization step, where specific antisense RNA or DNA probes anneal to the target nucleic acid sequence. This step is generally carried out at high temperatures and in a denaturing solution, called hybridization buffer, commonly containing 50% (v/v) formamide - a hazardous chemical. When applied to the soft-bodied hydrozoan medusa Clytia hemisphaerica, we found that this traditional hybridization approach was not fully satisfactory, causing extensive deterioration of morphology and tissue texture which compromised our observation and interpretation of results. We thus tested alternative solutions for in situ detection of gene expression and, inspired by optimized protocols for Northern and Southern blot analysis, we substituted the 50% formamide with an equal volume of 8M urea solution in the hybridization buffer. Our new protocol not only yielded better morphologies and tissue consistency, but also notably improved the resolution of the signal, allowing more precise localization of gene expression and reducing aspecific staining associated with problematic areas. Given the improved results and reduced manipulation risks, we tested the urea protocol on other metazoans, two brachiopod species (Novocrania anomala and Terebratalia transversa) and the priapulid worm Priapulus caudatus, obtaining a similar reduction of aspecific probe binding. Overall, substitution of formamide by urea during in situ hybridization offers a safer alternative, potentially of widespread use in research, medical and teaching contexts. We encourage other workers to test this approach on their study organisms, and hope that they will also obtain better sample preservation, more precise expression patterns and fewer problems due to aspecific staining, as we report here for Clytia medusae and Novocrania and Terebratalia developing larvae.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Hidrozoos/metabolismo , Hibridación in Situ/métodos , Urea/química , Animales , Regulación de la Expresión Génica , Hidrozoos/genética , Especificidad de la Especie
5.
Front Zool ; 16: 28, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31333754

RESUMEN

BACKGROUND: The trochozoan excitatory peptide (EP) and its ortholog, the arthropod CCHamide, are neuropeptides that are only investigated in very few animal species. Previous studies on different trochozoan species focused on their physiological effect in adult specimens, demonstrating a myo-excitatory effect, often on tissues of the digestive system. The function of EP in the planktonic larvae of trochozoans has not yet been studied. RESULTS: We surveyed transcriptomes from species of various spiralian (Orthonectida, Nemertea, Brachiopoda, Entoprocta, Rotifera) and ecdysozoan taxa (Tardigrada, Onychophora, Priapulida, Loricifera, Nematomorpha) to investigate the evolution of EPs/CCHamides in protostomes. We found that the EPs of several pilidiophoran nemerteans show a characteristic difference in their C-terminus. Deorphanization of a pilidiophoran EP receptor showed, that the two splice variants of the nemertean Lineus longissimus EP activate a single receptor. We investigated the expression of EP in L. longissimus larvae and juveniles with customized antibodies and found that EP positive nerves in larvae project from the apical organ to the ciliary band and that EP is expressed more broadly in juveniles in the neuropil and the prominent longitudinal nerve cords. While exposing juvenile L. longissimus specimens to synthetic excitatory peptides did not show any obvious effect, exposure of larvae to either of the two EPs increased the beat frequency of their locomotory cilia and shifted their vertical swimming distribution in a water column upwards. CONCLUSION: Our results show that EP/CCHamide peptides are broadly conserved in protostomes. We show that the EP increases the ciliary beat frequency of L. longissimus larvae, which shifts their vertical distribution in a water column upwards. Endogenous EP may be released at the ciliary band from the projections of apical organ EP positive neurons to regulate ciliary beating. This locomotory function of EP in L. longissimus larvae stands in contrast to the repeated association of EP/CCHamides with its myo-excitatory effect in adult trochozoans and the general association with the digestive system in many protostomes.

6.
J Exp Biol ; 220(Pt 3): 425-436, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27852754

RESUMEN

Ammonia is a toxic waste product from protein metabolism and needs to be either converted into less toxic molecules or, in the case of fish and aquatic invertebrates, excreted directly as is. In contrast to fish, very little is known regarding the ammonia excretion mechanism and the participating excretory organs in marine invertebrates. In the current study, ammonia excretion in the marine burrowing polychaete Eurythoe complanata was investigated. As a potential site for excretion, the 100-200 µm long, 30-50 µm wide and up to 25 µm thick dentrically branched, well ventilated and vascularized branchiae (gills) were identified. In comparison to the main body, the branchiae showed considerably higher mRNA expression levels of Na+/K+-ATPase, V-type H+-ATPase, cytoplasmic carbonic anhydrase (CA-2), a Rhesus-like protein, and three different ammonia transporters (AMTs). Experiments on the intact organism revealed that ammonia excretion did not occur via apical ammonia trapping, but was regulated by a basolateral localized V-type H+-ATPase, carbonic anhydrase and intracellular cAMP levels. Interestingly, the V-type H+-ATPase seems to play a role in ammonia retention. A 1 week exposure to 1 mmol l-1 NH4Cl (HEA) did not cause a change in ammonia excretion rates, while the three branchial expressed AMTs showed a tendency to be down-regulated. This indicates a shift of function in the branchial ammonia excretion processes under these conditions.


Asunto(s)
Amoníaco/metabolismo , Anélidos/metabolismo , Branquias/metabolismo , Animales , Anélidos/genética , Anélidos/ultraestructura , Transporte Biológico , Anhidrasa Carbónica II/análisis , Anhidrasa Carbónica II/genética , Anhidrasa Carbónica II/metabolismo , AMP Cíclico/análisis , AMP Cíclico/genética , AMP Cíclico/metabolismo , Regulación de la Expresión Génica , Branquias/ultraestructura , Filogenia , ARN Mensajero/genética , ATPasa Intercambiadora de Sodio-Potasio/análisis , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , ATPasas de Translocación de Protón Vacuolares/análisis , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo
7.
BMC Med Ethics ; 17(1): 39, 2016 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-27405974

RESUMEN

Biobanks have been heralded as essential tools for translating biomedical research into practice, driving precision medicine to improve pathways for global healthcare treatment and services. Many nations have established specific governance systems to facilitate research and to address the complex ethical, legal and social challenges that they present, but this has not lead to uniformity across the world. Despite significant progress in responding to the ethical, legal and social implications of biobanking, operational, sustainability and funding challenges continue to emerge. No coherent strategy has yet been identified for addressing them. This has brought into question the overall viability and usefulness of biobanks in light of the significant resources required to keep them running. This review sets out the challenges that the biobanking community has had to overcome since their inception in the early 2000s. The first section provides a brief outline of the diversity in biobank and regulatory architecture in seven countries: Australia, Germany, Japan, Singapore, Taiwan, the UK, and the USA. The article then discusses four waves of responses to biobanking challenges. This article had its genesis in a discussion on biobanks during the Centre for Health, Law and Emerging Technologies (HeLEX) conference in Oxford UK, co-sponsored by the Centre for Law and Genetics (University of Tasmania). This article aims to provide a review of the issues associated with biobank practices and governance, with a view to informing the future course of both large-scale and smaller scale biobanks.


Asunto(s)
Discusiones Bioéticas , Bancos de Muestras Biológicas , Investigación Biomédica , Apoyo Financiero , Medicina de Precisión , Control Social Formal , Bancos de Muestras Biológicas/economía , Bancos de Muestras Biológicas/ética , Bancos de Muestras Biológicas/legislación & jurisprudencia , Investigación Biomédica/economía , Investigación Biomédica/ética , Investigación Biomédica/legislación & jurisprudencia , Humanos
8.
Angew Chem Int Ed Engl ; 54(35): 10308-12, 2015 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-26179443

RESUMEN

Imitating nature's approach in nucleophile-activated formaldehyde dehydrogenation, air-stable ruthenium complexes proved to be exquisite catalysts for the dehydrogenation of formaldehyde hydrate as well as for the transfer hydrogenation to unsaturated organic substrates at loadings as low as 0.5 mol %. Concatenation of the chemical hydrogen-fixation route with an oxidase-mediated activation of methanol gives an artificial methylotrophic in vitro metabolism providing methanol-derived reduction equivalents for synthetic hydrogenation purposes. Moreover, for the first time methanol reforming at room temperature was achieved on the basis of this bioinduced dehydrogenation path delivering hydrogen gas from aqueous methanol.


Asunto(s)
Formaldehído/química , Hidrógeno/química , Metanol/química , Rutenio/química , Hidrogenación , Oxidorreductasas/metabolismo , Temperatura
9.
Elife ; 122024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727714

RESUMEN

Neuropeptides are ancient signaling molecules in animals but only few peptide receptors are known outside bilaterians. Cnidarians possess a large number of G protein-coupled receptors (GPCRs) - the most common receptors of bilaterian neuropeptides - but most of these remain orphan with no known ligands. We searched for neuropeptides in the sea anemone Nematostella vectensis and created a library of 64 peptides derived from 33 precursors. In a large-scale pharmacological screen with these peptides and 161 N. vectensis GPCRs, we identified 31 receptors specifically activated by 1 to 3 of 14 peptides. Mapping GPCR and neuropeptide expression to single-cell sequencing data revealed how cnidarian tissues are extensively connected by multilayer peptidergic networks. Phylogenetic analysis identified no direct orthology to bilaterian peptidergic systems and supports the independent expansion of neuropeptide signaling in cnidarians from a few ancestral peptide-receptor pairs.


Asunto(s)
Neuropéptidos , Filogenia , Receptores Acoplados a Proteínas G , Anémonas de Mar , Animales , Anémonas de Mar/genética , Neuropéptidos/metabolismo , Neuropéptidos/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Transducción de Señal
10.
JMIR Cancer ; 9: e39631, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36719719

RESUMEN

BACKGROUND: Precision health offers the promise of advancing clinical care in data-driven, evidence-based, and personalized ways. However, complex data sharing infrastructures, for-profit (commercial) and nonprofit partnerships, and systems for data governance have been created with little attention to the values, expectations, and preferences of patients about how they want to be engaged in the sharing and use of their health information. We solicited patient opinions about institutional policy options using public deliberation methods to address this gap. OBJECTIVE: We aimed to understand the policy preferences of current and former patients with cancer regarding the sharing of health information collected in the contexts of health information exchange and commercial partnerships and to identify the values invoked and perceived risks and benefits of health data sharing considered by the participants when formulating their policy preferences. METHODS: We conducted 2 public deliberations, including predeliberation and postdeliberation surveys, with patients who had a current or former cancer diagnosis (n=61). Following informational presentations, the participants engaged in facilitated small-group deliberations to discuss and rank policy preferences related to health information sharing, such as the use of a patient portal, email or SMS text messaging, signage in health care settings, opting out of commercial data sharing, payment, and preservation of the status quo. The participants ranked their policy preferences individually, as small groups by mutual agreement, and then again individually in the postdeliberation survey. RESULTS: After deliberation, the patient portal was ranked as the most preferred policy choice. The participants ranked no change in status quo as the least preferred policy option by a wide margin. Throughout the study, the participants expressed concerns about transparency and awareness, convenience, and accessibility of information about health data sharing. Concerns about the status quo centered around a lack of transparency, awareness, and control. Specifically, the patients were not aware of how, when, or why their data were being used and wanted more transparency in these regards as well as greater control and autonomy around the use of their health data. The deliberations suggested that patient portals would be a good place to provide additional information about data sharing practices but that over time, notifications should be tailored to patient preferences. CONCLUSIONS: Our study suggests the need for increased disclosure of health information sharing practices. Describing health data sharing practices through patient portals or other mechanisms personalized to patient preferences would minimize the concerns expressed by patients about the extent of data sharing that occurs without their knowledge. Future research and policies should identify ways to increase patient control over health data sharing without reducing the societal benefits of data sharing.

11.
Nat Commun ; 14(1): 2814, 2023 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-37198188

RESUMEN

Bacterial symbioses allow annelids to colonise extreme ecological niches, such as hydrothermal vents and whale falls. Yet, the genetic principles sustaining these symbioses remain unclear. Here, we show that different genomic adaptations underpin the symbioses of phylogenetically related annelids with distinct nutritional strategies. Genome compaction and extensive gene losses distinguish the heterotrophic symbiosis of the bone-eating worm Osedax frankpressi from the chemoautotrophic symbiosis of deep-sea Vestimentifera. Osedax's endosymbionts complement many of the host's metabolic deficiencies, including the loss of pathways to recycle nitrogen and synthesise some amino acids. Osedax's endosymbionts possess the glyoxylate cycle, which could allow more efficient catabolism of bone-derived nutrients and the production of carbohydrates from fatty acids. Unlike in most Vestimentifera, innate immunity genes are reduced in O. frankpressi, which, however, has an expansion of matrix metalloproteases to digest collagen. Our study supports that distinct nutritional interactions influence host genome evolution differently in highly specialised symbioses.


Asunto(s)
Anélidos , Poliquetos , Animales , Simbiosis/genética , Anélidos/genética , Poliquetos/genética , Poliquetos/metabolismo , Genoma/genética , Genómica , Filogenia
12.
Am J Bioeth ; 17(9): 63-65, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28829254
13.
Nat Ecol Evol ; 5(2): 231-242, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33199869

RESUMEN

The causes and consequences of genome reduction in animals are unclear because our understanding of this process mostly relies on lineages with often exceptionally high rates of evolution. Here, we decode the compact 73.8-megabase genome of Dimorphilus gyrociliatus, a meiobenthic segmented worm. The D. gyrociliatus genome retains traits classically associated with larger and slower-evolving genomes, such as an ordered, intact Hox cluster, a generally conserved developmental toolkit and traces of ancestral bilaterian linkage. Unlike some other animals with small genomes, the analysis of the D. gyrociliatus epigenome revealed canonical features of genome regulation, excluding the presence of operons and trans-splicing. Instead, the gene-dense D. gyrociliatus genome presents a divergent Myc pathway, a key physiological regulator of growth, proliferation and genome stability in animals. Altogether, our results uncover a conservative route to genome compaction in annelids, reminiscent of that observed in the vertebrate Takifugu rubripes.


Asunto(s)
Anélidos , Evolución Molecular , Animales , Anélidos/genética , Ligamiento Genético , Genoma , Takifugu/genética
14.
Open Biol ; 7(8)2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28835571

RESUMEN

Animal behaviour often comprises spatially separated sub-reactions and even ciliated larvae are able to coordinate sub-reactions of complex behaviours (metamorphosis, feeding). How these sub-reactions are coordinated is currently not well understood. Neuropeptides are potential candidates for triggering larval behaviour. However, although their immunoreactivity has been widely analysed, their function in trochozoan larvae has only been studied for a few cases. Here, we investigate the role of neuropeptides in the defence behaviour of brachiopod larvae. When mechanically disturbed, the planktonic larvae of Terebratalia transversa protrude their stiff chaetae and sink down slowly. We identified endogenous FLRFamide-type neuropeptides (AFLRFamide and DFLRFamide) in T. transversa larvae and show that the protrusion of the chaetae as well as the sinking reaction can both be induced by each of these peptides. This also correlates with the presence of FLRFamidergic neurons in the apical lobe and adjacent to the trunk musculature. We deorphanized the AFLRFamide/DFLRFamide receptor and detected its expression in the same tissues. Furthermore, the ability of native and modified FLRFamide-type peptides to activate this receptor was found to correspond with their ability to trigger behavioural responses. Our results show how FLRFamide-type neuropeptides can induce two coherent sub-reactions in a larva with a simple nervous system.


Asunto(s)
FMRFamida/metabolismo , Receptores de Péptidos de Invertebrados/metabolismo , Zooplancton/fisiología , Animales , Conducta Animal , Invertebrados , Larva/fisiología , Neuronas/metabolismo , Zooplancton/metabolismo
15.
J Community Genet ; 8(3): 183-197, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28382416

RESUMEN

Scholarship on newborn screening, dried bloodspot retention, and large population biobanking call consistently for improved public engagement. Communication with participants likely occurs only in the context of collection, consent, or notification, if at all. We ran an 11-week advertising campaign to inform Michigan Facebook users unlikely to know that their or their children's dried bloodspots (DBSs) were stored in a state biobank. We investigated the pattern and content of comments posted during the campaign, focusing on users' questions, attitudes and concerns, and the role the moderator played in addressing them. We used Facebook data to quantitatively assess engagement and employed conventional content analysis to investigate themes, attitudes, and social dynamics among user and moderator comments. Five ad sets elicited comments during campaign weeks 4-8, reaching ∼800,000 Facebook users ($6000). Gravitating around broad, underlying ethical, legal, and social issues, 180 posts from 129 unique users related to newborn screening or biobanking. Thirty six conveyed negative attitudes and 33 conveyed positive attitudes; 53 posed questions. The most prevalent themes identified were consent, privacy, bloodspot use, identifiability, inclusion criteria, research benefits, (mis)trust, genetics, DBS destruction, awareness, and the role of government. The moderator's 81 posts were responsive-answering questions, correcting or clarifying information, or providing information about opting out. Facebook ad campaigns can improve engagement by pushing out relevant content and creating dynamic, responsive, visible forums for discussion. Reduced control over messaging may be worth the trade-off for creating accessible, transparent, people-centered engagement on public health issues that are sensitive and complex.

16.
Structure ; 12(3): 477-86, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15016363

RESUMEN

ADP-ribosyl cyclase catalyzes the elimination of nicotinamide from NAD and cyclization to cADPR, a known second messenger in cellular calcium signaling pathways. We have determined to 2.0 A resolution the structure of Aplysia cyclase with ribose-5-phosphate bound covalently at C3' and with the base exchange substrate (BES), pyridylcarbinol, bound to the active site. In addition, further refinement at 2.4 A resolution of the structure of nicotinamide-bound cyclase, which was previously reported, reveals that ribose-5-phosphate is also covalently bound in this structure, and a second nicotinamide site was identified. The structures of native and mutant Glu179Ala cyclase were also solved to 1.7 and 2.0 A respectively. It is proposed that the second nicotinamide site serves to promote cyclization by clearing the active site of the nicotinamide byproduct. Moreover, a ribosylation mechanism can be proposed in which the cyclization reaction proceeds through a covalently bound intermediate.


Asunto(s)
ADP-Ribosil Ciclasa/química , ADP-Ribosil Ciclasa/metabolismo , Secuencia de Aminoácidos , Animales , Aplysia/enzimología , Secuencia Conservada , Cristalografía por Rayos X , Datos de Secuencia Molecular , Mononucleótido de Nicotinamida/metabolismo , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Ribosamonofosfatos/metabolismo , Alineación de Secuencia
17.
JMIR Public Health Surveill ; 2(1): e27, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27244774

RESUMEN

BACKGROUND: The interpersonal, dialogic features of social networking sites have untapped potential for public health communication. We ran a Facebook advertising campaign to raise statewide awareness of Michigan's newborn screening and biobanking programs. OBJECTIVE: We ran a Facebook advertising campaign to stimulate public engagement on the complex and sensitive issue of Michigan's newborn screening and biobank programs. METHODS: We ran an 11-week, US $15,000 Facebook advertising campaign engaging Michigan Facebook users aged 18-64 years about the state's newborn screening and population biobank programs, and we used a novel "engagement spectrum" framework to contextualize and evaluate engagement outcomes ranging from observation to multi-way conversation. RESULTS: The campaign reached 1.88 million Facebook users, yielding a range of engagement outcomes across ad sets that varied by objective, content, budget, duration, and bid type. Ad sets yielded 9009 page likes (US $4125), 15,958 website clicks (US $5578), and 12,909 complete video views to 100% (US $3750). "Boosted posts" yielded 528 comments and 35,966 page post engagements (US $1500). Overall, the campaign led to 452 shares and 642 comments, including 176 discussing newborn screening and biobanking. CONCLUSIONS: Facebook advertising campaigns can efficiently reach large populations and achieve a range of engagement outcomes by diversifying ad types, bid types, and content. This campaign provided a population-based approach to communication that also increased transparency on a sensitive and complex topic by creating a forum for multi-way interaction.

19.
J Mol Biol ; 339(2): 437-45, 2004 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-15136045

RESUMEN

In order to understand the structural basis for the high thermostability of phytase from Aspergillus fumigatus, its crystal structure was determined at 1.5 A resolution. The overall fold resembles the structure of other phytase enzymes. Aspergillus niger phytase shares 66% sequence identity, however, it is much less heat-resistant. A superimposition of these two structures reveals some significant differences. In particular, substitutions with polar residues appear to remove repulsive ion pair interactions and instead form hydrogen bond interactions, which stabilize the enzyme; the formation of a C-terminal helical capping, induced by arginine residue substitutions also appears to be critical for the enzyme's ability to refold to its active form after denaturation at high temperature. The heat-resilient property of A.fumigatus phytase could be due to the improved stability of regions that are critical for the refolding of the protein; and a heat-resistant A.niger phytase may be achieved by mutating certain critical residues with the equivalent residues in A.fumigatus phytase. Six predicted N-glycosylation sites were observed to be glycosylated from the experimental electron density. Furthermore, the enzyme's catalytic residue His59 was found to be partly phosphorylated and thus showed a reaction intermediate, providing structural insight, which may help understand the catalytic mechanism of the acid phosphatase family. The trap of this catalytic intermediate confirms the two-step catalytic mechanism of the acid histidine phosphatase family.


Asunto(s)
6-Fitasa/química , Aspergillus fumigatus/enzimología , Histidina/química , 6-Fitasa/metabolismo , Secuencia de Aminoácidos , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Estabilidad de Enzimas , Glicosilación , Calor , Enlace de Hidrógeno , Datos de Secuencia Molecular , Conformación Proteica , Homología de Secuencia de Aminoácido
20.
Public Health Genomics ; 18(1): 26-39, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25359560

RESUMEN

BACKGROUND: Michigan's BioTrust for Health, a public health research biobank comprised of residual dried bloodspot (DBS) cards from newborn screening contains over 4 million samples collected without written consent. Participant-centric initiatives are IT tools that hold great promise to address the consent challenges in biobank research. METHODS: Working with Private Access Inc., a pioneer in patient-centric web solutions, we created and pilot tested a dynamic informed consent simulation, paired with an educational website, focusing on consent for research utilizing DBSs in Michigan's BioTrust for Health. RESULTS: Out of 187 pilot testers recruited in 2 groups, 137 completed the consent simulation and exit survey. Over 50% indicated their willingness to set up an account if the simulation went live and to recommend it to others. Participants raised concerns about the process of identity verification and appeared to have little experience with sharing health information online. CONCLUSIONS: Applying online, dynamic approaches to address the consent challenges raised by biobanks with legacy sample collections should be explored, given the positive reaction to our pilot test and the strong preference for active consent. Balancing security and privacy with accessibility and ease of use will continue to be a challenge.


Asunto(s)
Acceso a la Información/ética , Bancos de Muestras Biológicas , Simulación por Computador , Confidencialidad/ética , Consentimiento Informado , Adulto , Bancos de Muestras Biológicas/ética , Bancos de Muestras Biológicas/organización & administración , Investigación Biomédica/ética , Investigación Biomédica/organización & administración , Femenino , Humanos , Recién Nacido , Difusión de la Información , Masculino , Michigan , Persona de Mediana Edad , Tamizaje Neonatal , Proyectos Piloto , Manejo de Especímenes
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