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1.
Br J Educ Psychol ; 94(1): 282-305, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37984992

RESUMO

BACKGROUND: Despite evidence that synthetic phonics teaching has increased reading attainments, a sizable minority of children struggle to acquire phonics skills and teachers lack clear principles for deciding what types of additional support are most beneficial. Synthetic phonics teaches children to read using a decoding strategy to translate letters into sounds and blend them (e.g., c-a-t = "k - ae - t" = "cat"). To use a decoding strategy, children require letter-sound knowledge (LSK) and the ability to blend sound units (phonological awareness; PA). Training on PA has been shown to benefit struggling beginning readers. However, teachers in English primary schools do not routinely check PA. Instead, struggling beginner readers usually receive additional LSK support. AIMS: Until now, there has been no systematic comparison of the effectiveness of training on each component of the decoding process. Should additional support for struggling readers focus on improving PA, or on supplementary LSK and/or decoding instruction? We aim to increase understanding of the roles of LSK and PA in children's acquisition of phonics skills and uncover which types of additional training are most likely to be effective for struggling beginner readers. SAMPLE AND METHOD: We will compare training on each of these components, using a carefully controlled experimental design. We will identify reception-age children at risk of reading difficulties (target n = 225) and randomly allocate them to either PA, LSK or decoding (DEC) training. We will test whether training type influences post-test performance on word reading and whether any effects depend on participants' pre-test PA and/or LSK. RESULTS AND CONCLUSIONS: Two hundred and twenty-two participants completed the training. Planned analyses showed no effects of condition on word reading. However, exploratory analyses indicated that the advantage of trained over untrained words was significantly greater for the PA and DEC conditions. There was also a significantly greater improvement in PA for the DEC condition. Overall, our findings suggest a potential advantage of training that includes blending skills, particularly when decoding words that had been included in training. Future research is needed to develop a programme of training on blending skills combined with direct vocabulary instruction for struggling beginner readers.


Assuntos
Pessoal de Educação , Fonética , Criança , Humanos , Cognição , Leitura , Vocabulário
2.
Vet Rec ; 192(3): 131, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36734558
3.
Eur J Sport Sci ; 22(8): 1196-1203, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34187318

RESUMO

This study examined the role of fundamental movement skills (FMS) and perceived competence in the relationship between physical fitness and technical soccer skills in children. Seventy boys aged 7-12 years of age (Mean ± SD = 9 ± 2 years) who were regularly engaged in grassroots soccer participated in the present study. The Test of Gross Motor Development-2 (Ulrich, 2001. Test of gross motor development (2nd ed.). Austin, TX: PRO-ED) was used to assess FMS and the Perceived Physical Ability Scale for Children (Colella, Morano, Bortoli, & Robazza, 2008. A physical self-efficacy scale for children. Social Behavior and Personality: an International Journal, 36, 841-848) was used to assess perceived competence. Technical skill was determined from three tests reflecting dribbling, passing and shooting. Z-scores of each measure were summed, creating a composite measure of technical skill. Three measures of physical fitness were employed; 15m sprint time, standing long jump, and seated medicine ball (1kg) throw. Z-scores for each measure were summed creating a composite measure of physical fitness. The relationship between technical skill and FMS, fitness, perceived competence and age was examined via path analysis. Results indicated two significant mediated pathways: from physical fitness to technical skills via FMS, and from physical fitness to technical skills via perceived competence. Once these mediators had been accounted for, there was no direct link from physical fitness to technical skills. Coaches should therefore seek to avoid one-sided delivery of practice by not solely focusing on football type drills, and focusing on a range of activities which enhance a broad foundation of FMS and promote strategies to positively influence a child's perception of their own competence.HighlightsFundamental movement skills (FMS) are considered the foundation for physical activity and sport performance yet they tend to be overlooked, in favour of physical fitness, in the development of soccer talent.We examined mediating effects of FMS and perceived competence in the relationship between physical fitness and technical soccer skills in 70, 7-12 year old grassroots soccer players.We suggests there is no direct effect of physical fitness on technical skills in soccer but both FMS and perceived competence act as mediators of the physical fitness-technical skill relationship in children aged 7-12 years old.Coaches should therefore look to develop a broad base of FMS and a higher perception of competence to improve children's technical soccer skills.


Assuntos
Futebol , Aptidão , Criança , Exercício Físico , Humanos , Masculino , Destreza Motora , Aptidão Física
4.
Br J Educ Psychol ; 92(1): 105-130, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34244991

RESUMO

BACKGROUND: Despite the fact that literacy instruction is a main focus of primary education, many children struggle to meet nationally set standards. AIMS: We aimed to test which components of a comprehensive reading programme (ABRACADABRA: https://eur03.safelinks.protection. OUTLOOK: com/?url=https%3A%2F%2Fdoi.org%2F10.1186%2FISRCTN18254678&data=04%7C01%7Cjanet.vousden%40ntu.ac.uk%7C880280e0b00749df855308d94068a0bb%7C8acbc2c5c8ed42c78169ba438a0dbe2f%7C1%7C0%7C637611640381216902%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=%2B4U9sGfofkyCPEY7lWz8n3TPoMOAeJMXyFwdhW6EpUw%3D&reserved=0) mediated the effect of the programme on nationally assessed literacy outcomes. SAMPLE: Following blind allocation, 516 Year 1 pupils from 40 schools were randomized to the programme group, and 908 Year 1 pupils, to a control condition. METHODS: Pupils in the programme completed 20 weeks of instruction in grapheme/phoneme knowledge, decoding, and comprehension. Control children received regular classroom instruction. RESULTS: Children in the programme group were significantly better at these taught skills after the programme finished (effect sizes: grapheme/phoneme knowledge, ß = .33, 95% CI [0.09-0.57]; decoding, ß = .26, 95% CI [0.09-0.43]; and comprehension, ß = .26, 95% CI [0.05-0.47]). Improvements in the programme group's decoding and comprehension skills fully mediated the improvements in national literacy assessments serving as a delayed post-test 12 months after the programme. Programme group pupils were 2.3 (95% CI [1.4-4.1]) times more likely to achieve/exceed the expected standard in reading, and 1.8 (95% CI [1.2-2.6]) times more likely to achieve/exceed the expected standard in writing due to an increase in the trained skills. CONCLUSIONS: These results provide strong evidence that a programme that incorporates decoding and comprehension instruction for typically developing beginning readers improves distal educational outcomes in reading and writing through increasing proficiencies targeted by the reading programme.


Assuntos
Dislexia , Leitura , Criança , Compreensão , Humanos , Alfabetização , Redação
5.
Dev Sci ; 24(1): e12986, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32412095

RESUMO

We reconcile competing theories of the role of phonological memory in reading development, by uncovering their dynamic relationship during the first 5 years of school. Phonological memory, reading and phoneme awareness were assessed in 780 phonics-educated children at age 4, 5, 6 and 9. Confirmatory factor analyses demonstrated that phonological memory loaded onto two factors: verbal short-term memory (verbal STM; phonological tasks that loaded primarily on serial order memory) and nonword repetition. Using longitudinal structural equation models, we found that verbal STM directly predicted early word-level reading from age 4 to 6, reflecting the importance of serial-order memory for letter-by-letter decoding. In contrast, reading had no reciprocal influence on the development of verbal STM. The relationship between nonword repetition and reading was bidirectional across the 5 years of study: nonword repetition and reading predicted each other both directly and indirectly (via phoneme awareness). Indirect effects from nonword repetition (and verbal STM) to reading support the view that phonological memory stimulates phonemically detailed representations through repeated encoding of complex verbal stimuli. Similarly, the indirect influence of reading on nonword repetition suggests that improved reading ability promotes the phoneme-level specificity of phonological representations. Finally, the direct influence from reading to nonword repetition suggests that better readers use orthographic cues to help them remember and repeat new words accurately. A video abstract of this article can be viewed at https://www.youtube.com/watch?v=70LZfTR0BjE.


Assuntos
Fonética , Leitura , Criança , Pré-Escolar , Humanos , Estudos Longitudinais , Memória de Curto Prazo , Rememoração Mental
7.
Anal Chem ; 91(14): 8908-8917, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31251585

RESUMO

Influenza vaccine potency is determined by the quantification of immunologically active hemagglutinin capable of eliciting neutralizing antibodies upon immunization. Currently, the single radial immunodiffusion (SRID) method is the standard in vitro potency assay used for lot release of seasonal inactivated influenza vaccines. Despite the proven usage of SRID, significant limitations such as the time-consuming preparation of reagents and limited dynamic range warrant the need for the development of alternative potency assays. Such alternative approaches need to discriminate and quantify relevant hemagglutinin material, provide strain identity, and be independent of strain-specific and seasonal reagents. Herein, we present a proof of concept method that combines the capture of conformationally well-folded hemagglutinin via a sialic acid binding step with the resolving power of reversed-phase high-performance liquid chromatography for strain identity and determination. Details of the protocol for the selective capture of receptor-binding hemagglutinin, its release from the receptor, and its relative determination are presented. This approach was found to provide flexibility for the reagents to be used and was adaptable to varying strain compositions of influenza vaccines. This proof of concept approach was developed as an antibody-independent methodology.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A/imunologia , Vacinas contra Influenza/imunologia , Animais , Aves , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa , Glicoproteínas de Hemaglutininação de Vírus da Influenza/isolamento & purificação , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/imunologia , Influenza Aviária/prevenção & controle , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Modelos Moleculares , Ácido N-Acetilneuramínico/química , Potência de Vacina , Vacinas de Produtos Inativados/imunologia
8.
ChemMedChem ; 14(14): 1321-1324, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31183991

RESUMO

We recently identified AG1, a small-molecule activator that functions by promoting oligomerization of glucose-6-phosphate dehydrogenase (G6PD) to the catalytically competent forms. Biochemical experiments indicate that the activation of G6PD by the original hit molecule (AG1) is noncovalent and that one C2 -symmetric region of the G6PD homodimer is important for ligand function. Consequently, the disulfide in AG1 is not required for activation of G6PD, and a number of analogues were prepared without this reactive moiety. Our study supports a mechanism of action whereby AG1 bridges the dimer interface at the structural nicotinamide adenine dinucleotide phosphate (NADP+ ) binding sites of two interacting G6PD monomers. Small molecules that promote G6PD oligomerization have the potential to provide a first-in-class treatment for G6PD deficiency. This general strategy could be applied to other enzyme deficiencies in which control of oligomerization can enhance enzymatic activity and/or stability.


Assuntos
Ativadores de Enzimas/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Indóis/metabolismo , Sítios de Ligação , Ativadores de Enzimas/síntese química , Glucosefosfato Desidrogenase/química , Glucosefosfato Desidrogenase/genética , Humanos , Indóis/síntese química , Ligantes , Simulação de Acoplamento Molecular , Mutação , NADP/química , NADP/metabolismo , Ligação Proteica , Multimerização Proteica/efeitos dos fármacos
9.
Cell Chem Biol ; 26(7): 1013-1026.e4, 2019 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-31105061

RESUMO

Immune targeting of (glyco)protein tumor markers has been useful to develop cancer and virus vaccines. However, the ganglioside family of tumor-associated glycolipids remains intractable to vaccine approaches. Here we show that synthetic antigens mimicking the carbohydrate moiety of GD2 or GD3 gangliosides can be used as vaccines to activate a selective humoral and cellular immunity that is therapeutic against several cancers expressing GD2 or GD3. Adoptive transfer of T cells generated after vaccination elicits tumor-infiltrating lymphocytes of the γδ T cell receptor and CD8+ phenotypes; and affords a high therapeutic index. The glycomimetic vaccine principles can be expanded to target the family of tumor gangliosides and other carbohydrates expressed primarily in pathological states.


Assuntos
Vacinas Anticâncer/imunologia , Gangliosídeos/imunologia , Glicolipídeos/imunologia , Animais , Anticorpos Monoclonais , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Feminino , Gangliosídeos/uso terapêutico , Humanos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Linfócitos do Interstício Tumoral/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T/imunologia , Vacinação/métodos
10.
Front Microbiol ; 10: 156, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30787920

RESUMO

Lake Fryxell, situated in the McMurdo Dry Valleys of Antarctica, is an intriguing aquatic ecosystem because of its perennial ice cover, highly stratified water column, and extreme physicochemical conditions, which collectively restrict lake biodiversity to solely microbial forms. To expand our current understanding of the cultivable biodiversity of Lake Fryxell, water samples were collected from depths of 10 and 17 m, and pure cultures of eight diverse strains of aerobic, chemoorganotrophic bacteria were obtained. Despite having high 16S rRNA gene sequence similarity to mesophilic bacteria inhabiting various temperate environments, all Lake Fryxell isolates were psychrotolerant, with growth occurring at 0°C and optimal growth from 18-24°C for all isolates. Phylogenetic analyses showed the isolates to be members of six taxonomic groups, including the genera Brevundimonas, Arthrobacter, Sphingobium, Leifsonia, and Pseudomonas, as well as the family Microbacteriaceae (one strain could not reliably be assigned to a specific genus based on our analysis). Pseudomonas strain LFY10 stood out as a useful tool for teaching laboratory activities because of its substantial cold adaptation (visible growth is evident in 1-2 days at 4°C), beta-hemolytic activity, and halotolerance to 8.5% (w/v) NaCl. These cold-adapted bacteria likely play a role in carbon mineralization and other nutrient cycling in Lake Fryxell, and their characterization broadens our understanding of microbial biodiversity in aquatic polar ecosystems.

11.
Protein Eng Des Sel ; 30(6): 431-440, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28475686

RESUMO

In many cases of familial amyotrophic lateral sclerosis (ALS), mutant forms of the Cu,Zn superoxide dismutase protein (SOD1) misfold and aggregate in motor neurons. Monomers of the normally homodimeric SOD1 have been found in patient tissue, presymptomatic mouse models of ALS, and in vitro misfolding assays which suggests that monomerization might be an early step in the pathological SOD1 misfolding pathway. In this study, we targeted the dimer interface with small molecules that might act as chemical chaperones to stabilize the native dimer and prevent downstream misfolding and aggregation. We performed a computational screen with a library of ~4400 drugs and natural compounds that were docked to two pockets around the SOD1 dimer interface. Of the resultant hits, seven were tested for misfolding and aggregation inhibition activity with A4V mutant SOD1. Quercitrin, quercetin-3-ß-d-glucoside (Q3BDG), and, to a markedly lesser extent, epigallocatechin gallate (EGCG) were found to combat misfolding and aggregation induced by hydrogen peroxide, a physiologically relevant stress, as assessed by a gel-based assay and 8-anilinonaphthalene-1-suflonic acid (ANS) fluorescence. Isothermal titration calorimetry (ITC) and a colourimetric assay determined that these molecules directly bind A4V SOD1. Based on these findings, we speculate that quercitrin and Q3BDG may be potential therapeutic inhibitors of misfolding and aggregation in SOD1-associated ALS.


Assuntos
Chaperonas Moleculares/metabolismo , Quercetina/análogos & derivados , Quercetina/metabolismo , Superóxido Dismutase-1/metabolismo , Descoberta de Drogas , Chaperonas Moleculares/química , Simulação de Acoplamento Molecular , Mutação , Dobramento de Proteína , Quercetina/química , Superóxido Dismutase-1/química , Superóxido Dismutase-1/genética
12.
Cell Rep ; 18(11): 2592-2599, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28297664

RESUMO

G6PD deficiency, an enzymopathy affecting 7% of the world population, is caused by over 160 identified amino acid variants in glucose-6-phosphate dehydrogenase (G6PD). The clinical presentation of G6PD deficiency is diverse, likely due to the broad distribution of variants across the protein and the potential for multidimensional biochemical effects. In this study, we use bioinformatic and biochemical analyses to interpret the relationship between G6PD variants and their clinical phenotype. Using structural information and statistical analyses of known G6PD variants, we predict the molecular phenotype of five uncharacterized variants from a reference population database. Through multidimensional analysis of biochemical data, we demonstrate that the clinical phenotypes of G6PD variants are largely determined by a trade-off between protein stability and catalytic activity. This work expands the current understanding of the biochemical underpinnings of G6PD variant pathogenicity and suggests a promising avenue for correcting G6PD deficiency by targeting essential structural features of G6PD.


Assuntos
Biocatálise , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Mutação/genética , Substituição de Aminoácidos , Bases de Dados de Proteínas , Glucosefosfato Desidrogenase/química , Humanos , Modelos Moleculares , Análise de Componente Principal , Estabilidade Proteica
13.
Curr Opin Struct Biol ; 44: 59-66, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28063303

RESUMO

Protein-protein interactions are essential for almost all intracellular and extracellular biological processes. Regulation of protein-protein interactions is one strategy to regulate cell fate in a highly selective manner. Specifically, peptides are ideal candidates for inhibition of protein-protein interactions because they can mimic a protein surface to effectively compete for binding. Additionally, peptides are synthetically accessible and can be stabilized by chemical modifications. In this review, we survey screening and rational design methods for identifying peptides to inhibit protein-protein interactions, as well as methods for stabilizing peptides to effectively mimic protein surfaces. In addition, we discuss recent applications of peptides to regulate protein-protein interactions for both basic research and therapeutic purposes.


Assuntos
Descoberta de Drogas/métodos , Peptídeos/farmacologia , Peptidomiméticos/farmacologia , Sequência de Aminoácidos , Animais , Humanos , Terapia de Alvo Molecular , Peptídeos/química , Peptidomiméticos/química , Ligação Proteica , Estrutura Secundária de Proteína
14.
Glycobiology ; 27(4): 358-369, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28096310

RESUMO

The Gram-negative bacterium Campylobacter jejuni 81116 (Penner serotype HS:6) has a class E lipooligosaccharide (LOS) biosynthesis locus containing 19 genes, which encode for 11 putative glycosyltransferases, 1 lipid A acyltransferase and 7 enzymes thought to be involved in the biosynthesis of dideoxyhexosamine (ddHexN) moieties. Although the LOS outer core structure of C. jejuni 81116 is still unknown, recent mass spectrometry analyses suggest that it contains acetylated forms of two ddHexN residues. For this investigation, five of the genes encoding enzymes reportedly involved in the biosyntheses of these sugar residues were examined, rmlA, rmlB, wlaRA, wlaRB and wlaRG. Specifically, these genes were cloned and expressed in Escherichia coli, and the corresponding enzymes were purified and tested for biochemical activity. Here we present data demonstrating that RmlA functions as a glucose-1-phosphate thymidylyltransferase and that RmlB is a thymidine diphosphate (dTDP)-glucose 4,6-dehydratase. We also show, through nuclear magnetic resonance spectroscopy and mass spectrometry analyses, that WlaRG, when utilized in coupled assays with either WlaRA or WlaRB and dTDP-4-keto-6-deoxyglucose, results in the production of either dTDP-3-amino-3,6-dideoxy-d-galactose (dTDP-Fuc3N) or dTDP-3-amino-3,6-dideoxy-d-glucose (dTDP-Qui3N), respectively. In addition, the X-ray crystallographic structures of the 3,4-ketoisomerases, WlaRA and WlaRB, were determined to 2.14 and 2.0 Å resolutions, respectively. Taken together, the data reported herein demonstrate that C. jejuni 81116 utilizes five enzymes to synthesize dTDP-Fuc3N or dTDP-Qui3N and that WlaRG, an aminotransferase, can function on sugars with differing stereochemistry about their C-4' carbons. Importantly, the data reveal that C. jejuni 81116 has the ability to synthesize two isomeric ddHexN forms.


Assuntos
Aciltransferases/genética , Campylobacter jejuni/genética , Galactose/genética , Glicosiltransferases/genética , Nucleotidiltransferases/genética , Aciltransferases/química , Aciltransferases/metabolismo , Vias Biossintéticas/genética , Campylobacter jejuni/enzimologia , Cristalografia por Raios X , Escherichia coli/genética , Galactose/química , Galactose/metabolismo , Glucose/química , Glucose/metabolismo , Glicosiltransferases/química , Glicosiltransferases/metabolismo , Lipopolissacarídeos/biossíntese , Lipopolissacarídeos/genética , Nucleotidiltransferases/química , Nucleotidiltransferases/metabolismo , Nucleotídeos de Timina/química , Nucleotídeos de Timina/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-29854050

RESUMO

A variety of plants synthesize natural products that either kill or inhibit the growth of various microorganisms. These plant products may serve as useful natural alternatives to synthetic antimicrobial pharmaceuticals and can be especially important in regions where commercial drugs are often not available. Despite this, the role of plants as producers of natural antimicrobial agents is often understated or even ignored in undergraduate biology curricula. In this laboratory exercise, students extract water-soluble constituents from two plants, Moringa oleifera (moringa) and Allium sativum (garlic), and determine their activity against both a gram-positive (Bacillus cereus strain 971) and a gram-negative (Escherichia coli strain K12) bacterium using a disk diffusion assay on Mueller-Hinton agar. Disks infused with commercially available antibiotics (e.g., penicillin and tetracycline) serve as controls. Following an incubation period of 24 hours, students obtain quantitative data by measuring zones of growth inhibition that develop as a result of strain sensitivity. To determine the effectiveness of the learning objectives, an unannounced quiz was administered both before and after the activity, and the students showed significant gains in their understanding of key concepts. Because this activity combines aspects of two major branches of biology-plant biology and microbiology-it is suitable for use as a laboratory exercise in courses related to either discipline, or it may be used as a laboratory component of a general biology course.

16.
Matters (Zur) ; 20172017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-30148135

RESUMO

Over 220 different amino acid variants have been identified in human glucose-6-phosphate dehydrogenase (G6PD), covering over 30% of the protein sequence. Many of these variants are pathogenic, causing varying degrees of G6PD deficiency with symptoms ranging from severe chronic anemia (class I) to milder triggered hemolytic episodes (classes II and III). The phenotypic effects of most G6PD variants have been reported, providing an opportunity to correlate phenotypic and structural information. In particular, we sought to investigate the tetramer interface of G6PD in relation to pathogenic variation, as there are conflicting reports indicating the importance of tetramerization for G6PD activity. Using a three-dimensional spatial scan statistic, hotspots of structural enrichment were identified for each class of pathogenic G6PD variants. Class I variants, the most phenotypically severe, were enriched at the dimer interface, consistent with previous evidence that dimerization is essential for G6PD activity. Class II variants were enriched near the tetramer interface, suggesting that tetramerization is also important for G6PD activity. This analysis explains why these two classes, both yielding 10% or less G6PD activity as compared to normal, lead to different clinical outcomes.

17.
Health Info Libr J ; 33(4): 323-328, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27870321

RESUMO

This feature has been co-authored by Anna Cunningham and her supervisor Frances Johnson. It is based on the research Anna conducted for her dissertation, which she completed as part of her MA in Library and Information Management at Manchester Metropolitan University. The study explored how people assess the trustworthiness of online health information, and the participants were asked to talk aloud whilst viewing information on the consumer health information website patients.co.uk. The study confirmed that their assessment was based on the information usefulness and credibility as well as identifying the factors relating to information quality and website design that helped to form these judgements. A. M.


Assuntos
Confiabilidade dos Dados , Comportamento de Busca de Informação , Mídias Sociais/normas , Confiança/psicologia , Humanos , Internet , Bibliotecários/educação , Biblioteconomia/educação , Pesquisa Qualitativa
18.
Clin Perinatol ; 43(2): 341-54, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27235212

RESUMO

Hyperbilirubinemia occurs frequently in newborns, and in severe cases can progress to kernicterus and permanent developmental disorders. Glucose-6-phosphate dehydrogenase (G6PD) deficiency, one of the most common human enzymopathies, is a major risk factor for hyperbilirubinemia and greatly increases the risk of kernicterus even in the developed world. Therefore, a novel treatment for kernicterus is needed, especially for G6PD-deficient newborns. Oxidative stress is a hallmark of bilirubin toxicity in the brain. We propose that the activation of G6PD via a small molecule chaperone is a potential strategy to increase endogenous defense against bilirubin-induced oxidative stress and prevent kernicterus.


Assuntos
Antioxidantes/uso terapêutico , Deficiência de Glucosefosfato Desidrogenase/metabolismo , Hiperbilirrubinemia Neonatal/terapia , Kernicterus/prevenção & controle , Chaperonas Moleculares/uso terapêutico , Fototerapia , Deficiência de Glucosefosfato Desidrogenase/complicações , Humanos , Hiperbilirrubinemia Neonatal/complicações , Hiperbilirrubinemia Neonatal/metabolismo , Recém-Nascido , Kernicterus/etiologia , Kernicterus/metabolismo , Kernicterus/terapia
19.
Int J Parasitol Drugs Drug Resist ; 6(1): 74-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27054066

RESUMO

Parasitic diseases cause ∼ 500,000 deaths annually and remain a major challenge for therapeutic development. Using a rational design based approach, we developed peptide inhibitors with anti-parasitic activity that were derived from the sequences of parasite scaffold proteins LACK (Leishmania's receptor for activated C-kinase) and TRACK (Trypanosoma receptor for activated C-kinase). We hypothesized that sequences in LACK and TRACK that are conserved in the parasites, but not in the mammalian ortholog, RACK (Receptor for activated C-kinase), may be interaction sites for signaling proteins that are critical for the parasites' viability. One of these peptides exhibited leishmanicidal and trypanocidal activity in culture. Moreover, in infected mice, this peptide was also effective in reducing parasitemia and increasing survival without toxic effects. The identified peptide is a promising new anti-parasitic drug lead, as its unique features may limit toxicity and drug-resistance, thus overcoming central limitations of most anti-parasitic drugs.


Assuntos
Leishmania/efeitos dos fármacos , Peptídeos/síntese química , Peptídeos/farmacologia , Proteínas de Protozoários/antagonistas & inibidores , Receptores de Superfície Celular/antagonistas & inibidores , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Desenho de Fármacos , Leishmania/química , Leishmania/genética , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Camundongos , Parasitemia/tratamento farmacológico , Peptídeos/administração & dosagem , Proteínas de Protozoários/química , Receptores de Quinase C Ativada , Receptores de Superfície Celular/química , Alinhamento de Sequência , Tripanossomicidas/administração & dosagem , Tripanossomicidas/química , Trypanosoma/genética , Tripanossomíase/tratamento farmacológico , Tripanossomíase/parasitologia
20.
J Biol Chem ; 291(26): 13608-21, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27129213

RESUMO

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an important glycolytic enzyme, has a non-catalytic (thus a non-canonical) role in inducing mitochondrial elimination under oxidative stress. We recently demonstrated that phosphorylation of GAPDH by δ protein kinase C (δPKC) inhibits this GAPDH-dependent mitochondrial elimination. δPKC phosphorylation of GAPDH correlates with increased cell injury following oxidative stress, suggesting that inhibiting GAPDH phosphorylation should decrease cell injury. Using rational design, we identified pseudo-GAPDH (ψGAPDH) peptide, an inhibitor of δPKC-mediated GAPDH phosphorylation that does not inhibit the phosphorylation of other δPKC substrates. Unexpectedly, ψGAPDH decreased mitochondrial elimination and increased cardiac damage in an animal model of heart attack. Either treatment with ψGAPDH or direct phosphorylation of GAPDH by δPKC decreased GAPDH tetramerization, which corresponded to reduced GAPDH glycolytic activity in vitro and ex vivo Taken together, our study identified the potential mechanism by which oxidative stress inhibits the protective GAPDH-mediated elimination of damaged mitochondria. Our study also identified a pharmacological tool, ψGAPDH peptide, with interesting properties. ψGAPDH peptide is an inhibitor of the interaction between δPKC and GAPDH and of the resulting phosphorylation of GAPDH by δPKC. ψGAPDH peptide is also an inhibitor of GAPDH oligomerization and thus an inhibitor of GAPDH glycolytic activity. Finally, we found that ψGAPDH peptide is an inhibitor of the elimination of damaged mitochondria. We discuss how this unique property of increasing cell damage following oxidative stress suggests a potential use for ψGAPDH peptide-based therapy.


Assuntos
Inibidores Enzimáticos/farmacologia , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/antagonistas & inibidores , Glicólise/efeitos dos fármacos , Peptídeos/farmacologia , Proteína Quinase C-delta/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Glicólise/fisiologia , Humanos , Masculino , Camundongos , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Proteína Quinase C-delta/genética , Multimerização Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Peixe-Zebra
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