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1.
Lancet ; 402 Suppl 1: S14, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37997053

RESUMO

BACKGROUND: In May 2018, the Scottish Government set a minimum unit price (MUP) of £0·50 per unit of alcohol sold in Scotland to reduce alcohol-related health harms. We synthesised evidence to establish the effects of MUP on alcohol-related health and social harms, at population level and within specific societal groups. METHODS: We did a theory-based synthesis of academic and grey research evidence about impacts of MUP in Scotland, including compliance, price, consumption, health outcomes, social outcomes, public attitudes, and the alcoholic drinks industry. We searched the Public Health Scotland's MUP evaluation portfolio and relevant grey and academic literature for studies published between Jan 1, 2018, and Jan 31, 2023. We conducted systematic searches and screening of bibliographic databases (Scopus, Public Health Database, EconLit, MEDLINE, ProQuest Public Health, Social Policy and Practice, NHS Scotland Knowledge Network Library Search, medRxiv, bioRxiv, SSRN, Idox Knowledge Exchange, Social Policy & Practice, and Google Search). Search terms were tailored to specific databases but included variants of the terms "minimum unit pricing", "alcohol", and "policy". Eligibility literature included English-language research into impacts of MUP on either the population of Scotland or a specific subpopulation. We excluded conference abstracts, literature reviews, articles that did not report research, and research based solely on data from before the introduction of MUP. FINDINGS: We included 40 reports in our analysis. On the balance of evidence, MUP improved population-level health outcomes, demonstrated most starkly by a 13·4% reduction in alcohol-attributable deaths in Scotland compared with England. There was no evidence of substantial negative effects on the alcoholic drinks industry or social harms at the population level. While population-level outcomes were predominantly positive, some qualitative evidence suggests that MUP might have exacerbated health and social harms for some individuals or groups, especially those with alcohol dependence who were financially vulnerable. INTERPRETATION: MUP in Scotland has been effective in reducing alcohol-related health harms, with little evidence of any effect on social harms. If MUP continues, policymakers should consider raising the £0·50 per unit threshold and supplementing the intervention with policies or services to address any unintended negative effects experienced by specific groups. The synthesis is persuasive due to the prospective, theory-based design of the evaluation portfolio and the quality and comprehensiveness of the evidence. FUNDING: Scottish Government.


Assuntos
Bebidas Alcoólicas , Etanol , Humanos , Estudos Prospectivos , Custos e Análise de Custo , Escócia/epidemiologia , Política Pública , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/prevenção & controle , Comércio
2.
Int J Sport Nutr Exerc Metab ; 30(4): 287-294, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470924

RESUMO

New Zealand blackcurrant (NZBC) contains anthocyanins, known to moderate blood flow and display anti-inflammatory properties that may improve recovery from exercise-induced muscle damage. The authors examined whether NZBC extract supplementation enhances recovery from exercise-induced muscle damage after a half-marathon race. Following a randomized, double-blind, independent groups design, 20 (eight women) recreational runners (age 30 ± 6 years, height 1.73 ± 0.74 m, body mass 68.5 ± 7.8 kg, half-marathon finishing time 1:56:33 ± 0:18:08 hr:min:s) ingested either two 300-mg/day capsules of NZBC extract (CurraNZ™) or a visually matched placebo, for 7 days prior to and 2 days following a half-marathon. Countermovement jump performance variables, urine interleukin-6, and perceived muscle soreness and fatigue were measured pre, post, and at 24 and 48 hr after the half-marathon and analyzed using a mixed linear model with statistical significance set a priori at p < .05. The countermovement jump performance variables were reduced immediately post-half-marathon (p < .05), with all returning to pre-half-marathon levels by 48 hr, except the concentric and eccentric peak force and eccentric duration, with no difference in response between groups (p > .05). Urine interleukin-6 increased 48-hr post-half-marathon in the NZBC group only (p < .01) and remained unchanged compared with pre-half-marathon levels in the placebo group (p > .05). Perceived muscle soreness and fatigue increased immediately post-half-marathon (p < .01) and returned to pre-half-marathon levels by 48 hr, with no difference between groups (p > .05). Supplementation with NZBC extract had no effect on the recovery of countermovement jump variables and perceptions of muscle soreness or fatigue following a half-marathon in recreational runners.


Assuntos
Corrida de Maratona , Fadiga Muscular/efeitos dos fármacos , Músculo Esquelético/fisiologia , Mialgia/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Ribes/química , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Masculino , Nova Zelândia , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
3.
Curr Genomics ; 14(4): 256-67, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24294106

RESUMO

Skeletal muscle is a post-mitotic tissue maintained by repair and regeneration through a population of stem cell-like satellite cells. Following muscle injury, satellite cell proliferation is mediated by local signals ensuring sufficient progeny for tissue repair. Age-related changes in satellite cells as well as to the local and systemic environment potentially impact on the capacity of satellite cells to generate sufficient progeny in an ageing organism resulting in diminished regeneration. 'Rejuvenation' of satellite cell progeny and regenerative capacity by environmental stimuli effectors suggest that a subset of age-dependent satellite cell changes may be reversible. Epigenetic regulation of satellite stem cells that include DNA methylation and histone modifications which regulate gene expression are potential mechanisms for such reversible changes and have been shown to control organismal longevity. The area of health and ageing that is likely to benefit soonest from advances in the biology of adult stem cells is the emerging field of regenerative medicine. Further studies are needed to elucidate the mechanisms by which epigenetic modifications regulate satellite stem cell function and will require an increased understanding of stem-cell biology, the environment of the aged tissue and the interaction between the two.

4.
J Diet Suppl ; 19(5): 672-688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33949254

RESUMO

New Zealand blackcurrant (NZBC) extract is a rich source of anthocyanins and in order to exert physiological effects, the anthocyanin-derived metabolites need to be bioavailable in vivo. We examined the plasma uptake of selected phenolic acids following NZBC extract supplementation alongside maintaining a habitual diet (i.e. not restricting habitual polyphenol intake). Twenty healthy volunteers (nine females, age: 28 ± 7 years, height 1.73 ± 0.09 m, body mass 73 ± 11 kg) consumed a 300 mg NZBC extract capsule (CurraNZ®; anthocyanin content 105 mg) following an overnight fast. Venous blood samples were taken pre and 1, 1.5, 2, 3, 4, 5, and 6 h post-ingestion of the capsule. Reversed-phase high-performance liquid chromatography (HPLC) was used for analysis of two dihydroxybenzoic acids [i.e. vanillic acid (VA) and protocatechuic acid (PCA)] and one trihydroxybenzoic acid [i.e. gallic acid (GA)] in plasma following NZBC extract supplementation. Habitual anthocyanin intake was 168 (95%CI:68-404) mg⋅day-1 and no associations were observed between this and VA, PCA, and GA plasma uptake by the NZBC extract intake. Plasma time-concentration curves revealed that GA, and PCA were most abundant at 4, and 1.5 h post-ingestion, representing a 261% and 320% increase above baseline, respectively, with VA remaining unchanged. This is the first study to demonstrate that an NZBC extract supplement increases the plasma uptake of phenolic acids GA, and PCA even when a habitual diet is followed in the days preceding the experimental trial, although inter-individual variability is apparent.


Assuntos
Antocianinas , Ribes , Adulto , Suplementos Nutricionais , Feminino , Ácido Gálico , Humanos , Masculino , Nova Zelândia , Extratos Vegetais , Ribes/química , Adulto Jovem
5.
Biochim Biophys Acta ; 1799(9): 642-52, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20800709

RESUMO

Antibodies to the six chicken histone H1 subtypes and the variant histone H5 have been used in immunoprecipitations of crosslinked chromatin fragments (xChIPs) to map linker histones across the ß-globin locus and the widely expressed glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and carbonic anhydrase (CA) genes in three cell types: 15-day embryo chicken erythrocytes, 15-day embryo chicken brain and the early erythroid cell line HD24. In erythrocytes, where the ß-adult and ß-hatching genes are active, the H1.01, H1.11L and H1.11R subtypes are substantially depleted throughout the ß-globin locus and the neighboring heterochromatin, in contrast to the other four subtypes, in particular the more abundant H5. Active genes therefore carry high levels of some but not all linker histone subtypes. The situation is similar in HD24 cells, except that substantial depletions are found at the promoters of the adult ß(A) and embryonic ß(ρ) and ß(ε) genes, despite these genes not yet being active in HD24 cells. The distributions in the brain tissue are characterised by the absence of H1.02, H1.03 and H5 from the hypersensitive site HS3 and from the ß-adult 3' enhancer for the H1.11L and H1.11R subtypes. The data show that although linker histone subtypes play distinct cell-type specific roles in gene regulation, their widespread distribution indicates they are not intrinsically inhibitory to basic chromatin transactions.


Assuntos
Histonas/genética , Histonas/metabolismo , Proteínas Repressoras/metabolismo , Animais , Embrião de Galinha , Imunoprecipitação da Cromatina , Mapeamento Cromossômico/métodos , Reagentes de Ligações Cruzadas/farmacologia , Regulação da Expressão Gênica , Loci Gênicos , Humanos , Ligação Proteica , Sequências Reguladoras de Ácido Nucleico/fisiologia , Proteínas Repressoras/classificação , Proteínas Repressoras/imunologia , Globinas beta/genética , Globinas beta/metabolismo
6.
Nat Cell Biol ; 6(1): 73-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14661024

RESUMO

Lysine residues within histones can be mono-, di - or tri-methylated. In Saccharomyces cerevisiae tri-methylation of Lys 4 of histone H3 (K4/H3) correlates with transcriptional activity, but little is known about this methylation state in higher eukaryotes. Here, we examine the K4/H3 methylation pattern at the promoter and transcribed region of metazoan genes. We analysed chicken genes that are developmentally regulated, constitutively active or inactive. We found that the pattern of K4/H3 methylation shows similarities to S. cerevisiae. Tri-methyl K4/H3 peaks in the 5' transcribed region and active genes can be discriminated by high levels of tri-methyl K4/H3 compared with inactive genes. However, our results also identify clear differences compared to yeast, as significant levels of K4/H3 methylation are present on inactive genes within the beta-globin locus, implicating this modification in maintaining a 'poised' chromatin state. In addition, K4/H3 di-methylation is not genome-wide and di-methylation is not uniformly distributed throughout the transcribed region. These results indicate that in metazoa, di- and tri-methylation of K4/H3 is linked to active transcription and that significant differences exist in the genome-wide methylation pattern as compared with S. cerevisiae.


Assuntos
Células Eucarióticas/metabolismo , Regulação da Expressão Gênica/genética , Histonas/metabolismo , Lisina/metabolismo , Metilação , Animais , Galinhas , Mapeamento Cromossômico , Genes/genética , Genoma , Globinas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Ativação Transcricional/genética
7.
Public Health Ethics ; 14(1): 109-116, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34234843

RESUMO

We have been asked to consider the feasibility of piloting a Citizens' Basic Income (CBI): a basic, unconditional, universal, individual, regular payment that would replace aspects of social security and be introduced alongside changes to taxes. Piloting and evaluating a CBI as a Cluster Randomized Control Trial (RCT) raises the question of whether intervention and comparison groups would be in equipoise, and thus whether randomization would be ethical. We believe that most researchers would accept that additional income, or reduced conditions on receiving income would be likely to improve health, especially at lower income levels. However, there are genuine uncertainties about the impacts on other outcomes, and CBI as a mechanism of providing income. There is also less consensus amongst civil servants and politicians about the impacts on health, and substantial disagreement about whether these would outweigh other impacts. We believe that an RCT is ethical because of these uncertainties. We also argue that the principle of equipoise should apply to randomized and non-randomized trials; that randomization is a fairer means of allocating to intervention and comparison groups; and that there is an ethical case for experimentation to generate higher-quality evidence for policymaking that may otherwise do harm.

8.
BMJ Open Sport Exerc Med ; 7(1): e000982, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33489310

RESUMO

OBJECTIVE: Altitude-related and exercise-related elevations in blood pressure (BP) increase the likelihood of developing pulmonary hypertension and high-altitude illness during high-altitude sojourn. This study examined the antihypertensive effect and potential exercise benefit of the angiotensin II receptor antagonist losartan when taken at altitude. METHODS: Twenty participants, paired for age and ACE genotype status, completed a double-blinded, randomised study, where participants took either losartan (100 mg/day) or placebo for 21 days prior to arrival at 5035 m (Whymper Hut, Mt Chimborazo, Ecuador). Participants completed a maximal exercise test on a supine cycle ergometer at sea level (4 weeks prior) and within 48 hours of arrival to 5035 m (10-day ascent). Power output, beat-to-beat BP, oxygen saturation (SpO2) and heart rate (HR) were recorded during exercise, with resting BP collected from daily medicals during ascent. Before and immediately following exercise at 5035 m, extravascular lung water prevalence was assessed with ultrasound (quantified via B-line count). RESULTS: At altitude, peak power was reduced relative to sea level (p<0.01) in both groups (losartan vs placebo: down 100±29 vs 91±28 W, p=0.55), while SpO2 (70±6 vs 70±5%, p=0.96) and HR (146±21 vs 149±24 bpm, p=0.78) were similar between groups at peak power, as was the increase in systolic BP from rest to peak power (up 80±37 vs 69±33 mm Hg, p=0.56). Exercise increased B-line count (p<0.05), but not differently between groups (up 5±5 vs 8±10, p=0.44). CONCLUSION: Losartan had no observable effect on resting or exercising BP, exercise-induced symptomology of pulmonary hypertension or performance at 5035 m.

9.
BMJ Open Sport Exerc Med ; 6(1): e000662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32341794

RESUMO

INTRODUCTION: Proteinuria increases at altitude and with exercise, potentially as a result of hypoxia. Using urinary alpha-1 acid glycoprotein (α1-AGP) levels as a sensitive marker of proteinuria, we examined the impact of relative hypoxia due to high altitude and blood pressure-lowering medication on post-exercise proteinuria. METHODS: Twenty individuals were pair-matched for sex, age and ACE genotype. They completed maximal exercise tests once at sea level and twice at altitude (5035 m). Losartan (100 mg/day; angiotensin-receptor blocker) and placebo were randomly assigned within each pair 21 days before ascent. The first altitude exercise test was completed within 24-48 hours of arrival (each pair within ~1 hour). Acetazolamide (125 mg two times per day) was administrated immediately after this test for 48 hours until the second altitude exercise test. RESULTS: With placebo, post-exercise α1-AGP levels were similar at sea level and altitude. Odds ratio (OR) for increased resting α1-AGP at altitude versus sea level was greater without losartan (2.16 times greater). At altitude, OR for reduced post-exercise α1-AGP (58% lower) was higher with losartan than placebo (2.25 times greater, p=0.059) despite similar pulse oximetry (SpO2) (p=0.95) between groups. Acetazolamide reduced post-exercise proteinuria by approximately threefold (9.3±9.7 vs 3.6±6.0 µg/min; p=0.025) although changes were not correlated (r=-0.10) with significant improvements in SpO2 (69.1%±4.5% vs 75.8%±3.8%; p=0.001). DISCUSSION: Profound systemic hypoxia imposed by altitude does not result in greater post-exercise proteinuria than sea level. Losartan and acetazolamide may attenuate post-exercise proteinuria, however further research is warranted.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31349618

RESUMO

The Scottish Government launched a tobacco control strategy in 2013 with the ambition of making Scotland tobacco smoke-free by 2034. However, 17% of the adult population in Scotland smoke cigarettes. This study aimed to provide insight into why policies are successful or not and provide suggestions for future policy actions. Individual interviews with ten tobacco control experts were conducted and the results were analyzed using thematic analysis. Key successes included strong political leadership, mass media campaigns, legislation to address availability and marketing of cigarettes and tobacco products, and legislation to reduce second-hand smoke exposure. Challenges included implementing policy actions, monitoring and evaluation of tobacco control actions, addressing health inequalities in smoking prevalence, and external factors that influenced the success of policy actions. Key suggestions put forward for future policy actions included addressing the price and availability of tobacco products, maintaining strong political leadership on tobacco control, building on the success of the 'Take it Right Outside' mass media campaign with further mass media campaigns to tackle other aspects of tobacco control, and developing and testing methods of addressing inequalities in cigarette smoking prevalence. The findings of this study can inform future tobacco control policy in Scotland and have relevance for tobacco control policies in other countries.


Assuntos
Atitude Frente a Saúde , Marketing/legislação & jurisprudência , Saúde Pública/legislação & jurisprudência , Prevenção do Hábito de Fumar/legislação & jurisprudência , Poluição por Fumaça de Tabaco/legislação & jurisprudência , Fumar Tabaco/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Escócia
11.
Nucleic Acids Res ; 34(14): 4025-35, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16914441

RESUMO

Native chromatin IP assays were used to define changes in core histone acetylation at the lysozyme locus during developmental maturation of chicken macrophages and stimulation to high-level expression by lipo-polysaccharide. In pluripotent precursors the lysozyme gene (Lys) is inactive and there is no acetylation of core histones at the gene, its promoter or at the upstream cis-control elements. In myeloblasts, where there is a very low level of Lys expression, H4 acetylation appears at the cis-control elements but not at the Lys gene or its promoter: neither H3 nor H2B become significantly acetylated in myeloblasts. In mature macrophages, Lys expression increases 5-fold: H4, H2B and H2A.Z are all acetylated at the cis-control elements but H3 remains unacetylated except at the -2.4 S silencer. Stimulation with LPS increases Lys expression a further 10-fold: this is accompanied by a rise in H3 acetylation throughout the cis-control elements; H4 and H2B acetylation remain substantial but acetylation at the Lys gene and its promoter remains low. Acetylation is thus concentrated at the cis-control elements, not at the Lys gene or its immediate promoter. H4 acetylation precedes H3 acetylation during development and H3 acetylation is most directly linked to high-level Lys expression.


Assuntos
Galinhas/genética , Elementos Facilitadores Genéticos , Histonas/metabolismo , Macrófagos/metabolismo , Muramidase/genética , Acetilação , Animais , Anticorpos , Linhagem Celular , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica no Desenvolvimento , Células Precursoras de Granulócitos/metabolismo , Histonas/imunologia , Muramidase/metabolismo , Células-Tronco Pluripotentes/metabolismo , RNA Mensageiro/metabolismo , Ativação Transcricional
12.
Nucleic Acids Res ; 33(17): 5633-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16204459

RESUMO

The replacement histone H2A.Z is variously reported as being linked to gene expression and preventing the spread of heterochromatin in yeast, or concentrated at heterochromatin in mammals. To resolve this apparent dichotomy, affinity-purified antibodies against the N-terminal region of H2A.Z, in both a triacetylated and non-acetylated state, are used in native chromatin immmuno-precipitation experiments with mononucleosomes from three chicken cell types. The hyperacetylated species concentrates at the 5' end of active genes, both tissue specific and housekeeping but is absent from inactive genes, while the unacetylated form is absent from both active and inactive genes. A concentration of H2A.Z is also found at insulators under circumstances implying a link to barrier activity but not to enhancer blocking. Although acetylated H2A.Z is widespread throughout the interphase genome, at mitosis its acetylation is erased, the unmodified form remaining. Thus, although H2A.Z may operate as an epigenetic marker for active genes, its N-terminal acetylation does not.


Assuntos
Histonas/análise , Transcrição Gênica , Acetilação , Animais , Anticorpos/imunologia , Células Cultivadas , Embrião de Galinha , Galinhas/genética , Histonas/imunologia , Histonas/metabolismo
13.
Curr Protoc Cell Biol ; 74: 17.20.1-17.20.10, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28256719

RESUMO

Techniques for studying RNA-protein interactions have lagged behind those for DNA-protein interactions as a consequence of the complexities associated with working with RNA. This unit describes a method for the adaptation of the In Situ Hybridization-Proximity Ligation Assay (ISH-PLA) to the study of RNA regulation (rISH-PLA). The rISH-PLA assay allows the identification of a given RNA-protein complex at subcellular and single-cell resolution, thus avoiding the lack of spatial resolution and sensitivity associated with assaying heterogeneous cell populations from which conventional RNA-protein interaction detection techniques suffer. This technique will be particularly usefully for studying the activity of RNA binding proteins (RBPs) in complex mixtures of cells, for example tissue sections or whole embryos. © 2017 by John Wiley & Sons, Inc.


Assuntos
Hibridização In Situ/métodos , Mapeamento de Interação de Proteínas/métodos , Proteínas de Ligação a RNA/análise , RNA/análise , Animais , Oócitos/metabolismo , RNA/química , Xenopus
14.
Gene ; 599: 78-86, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27836664

RESUMO

Vesicle shuttling is critical for many cellular and organismal processes, including embryonic development. GDI proteins contribute to vesicle shuttling by regulating the activity of Rab GTPases, controlling their cycling between the inactive cytosol and active membrane bound states. While identifying genes controlled by A-form DNA sequences we discovered a previously unknown member of the GDI family, GDI3. The GDI3 gene is found only in amphibians and fish and is developmentally expressed in Xenopus from neurula stages onwards in the neural plate, and subsequently in both dorsal and anterior structures. Depletion or over-expression of the GDI3 protein in Xenopus embryos gives rise to very similar phenotypes, suggesting that strict control of GDI3 protein levels is required for correct embryonic development. Our analysis suggests the evolutionary origins of GDI3 and that it is functionally distinct from GDI1. Predicted structural analysis of GDI3 suggests that the key difference between GDI1 and GDI3 lies in their lipid binding pockets.


Assuntos
Inibidores de Dissociação do Nucleotídeo Guanina/metabolismo , Neurogênese/fisiologia , Proteínas de Xenopus/metabolismo , Xenopus/embriologia , Xenopus/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Inibidores de Dissociação do Nucleotídeo Guanina/química , Inibidores de Dissociação do Nucleotídeo Guanina/genética , Modelos Moleculares , Neurogênese/genética , Filogenia , Xenopus/genética , Proteínas de Xenopus/química , Proteínas de Xenopus/genética , Proteínas rab de Ligação ao GTP/química , Proteínas rab de Ligação ao GTP/genética
15.
Biochim Biophys Acta ; 1729(1): 57-63, 2005 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-15823506

RESUMO

Formaldehyde-crosslinked and sonicated chromatin fragments were obtained from 15-day chicken embryo erythrocytes and purified on caesium chloride gradients. Polyclonal antibodies raised against chicken HMGB1 were used to immuno-precipitate fragments carrying HMGB1 in two protocols: (1) affinity purified antibodies covalently coupled to agarose beads and (2) diluted antiserum. The DNA of the antibody-bound chromatin was quantified and its sequence content assessed by quantitative real-time PCR to give values of the absolute enrichments generated. Amplicons were monitored within the active beta-globin locus, in the adjacent heterochromatin, in the lysozyme locus (containing an active housekeeping gene and the inactive lysozyme gene) and at the promoter of the inactive ovalbumin gene. For all amplicons the Bound/Input ratio was close to unity, implying no preferential location of HMGB1 on the chromatin. This initially unexpected result can now be understood in the light of the exceptional mobility of HMGB1 revealed by FLIP experiments showing that only 1-2 s are needed for HMGB1 to cross the nucleus: crosslinking times of 1 min were used in the present experiments.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Eritrócitos/metabolismo , Proteína HMGB1/metabolismo , Heterocromatina/metabolismo , Matriz Nuclear/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Embrião de Galinha , Imunoprecipitação da Cromatina , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica , Locos de Características Quantitativas/fisiologia
16.
PLoS One ; 11(1): e0147967, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26824753

RESUMO

Techniques for studying RNA-protein interactions have lagged behind those for DNA-protein complexes as a consequence of the complexities associated with working with RNA. Here we present a method for the modification of the existing In Situ Hybridisation-Proximity Ligation Assay (ISH-PLA) protocol to adapt it to the study of RNA regulation (rISH-PLA). As proof of principle we used the well-characterised interaction of the Xenopus laevis Staufen RNA binding protein with Vg1 mRNA, the complex of which co-localises to the vegetal pole of Xenopus oocytes. The applicability of both the Stau1 antibody and the Locked Nucleic Acid probe (LNA) recognising Vg1 mRNA were independently validated by whole-mount Immunohistochemistry and whole-mount in situ hybridisation assays respectively prior to combining them in the rISH-PLA assay. The rISH-PLA assay allows the identification of a given RNA-protein complex at subcellular and single cell resolution, thus avoiding the lack of spatial resolution and sensitivity associated with assaying heterogenous cell populations from which conventional RNA-protein interaction detection techniques suffer. This technique will be particularly usefully for studying the activity of RNA binding proteins (RBPs) in complex mixtures of cells, for example tissue sections or whole embryos.


Assuntos
Bioensaio , Imuno-Histoquímica/métodos , Oócitos/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Análise de Célula Única/métodos , Proteínas de Xenopus/metabolismo , Animais , Anticorpos/química , Sítios de Ligação , Biotina/química , Expressão Gênica , Hibridização In Situ , Camundongos , Oligonucleotídeos/química , Oócitos/citologia , Ligação Proteica , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Coelhos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Proteínas de Xenopus/genética , Xenopus laevis
17.
Mol Biotechnol ; 20(1): 1-15, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11876294

RESUMO

The analysis of protein interactions with chromatin is vital for the understanding of DNA sequence recognition in vivo. Chromatin binding requires the interaction of proteins with DNA lying on the macromolecular protein surface of nucleosomes, a situation that can alter factor binding characteristics substantially when compared with naked DNA. It is therefore important to study these protein-DNA interactions in the context of a chromatin substrate, the more physiologically relevant binding situation. In this article we review techniques used in the investigation of protein interactions with defined nucleosomal templates.


Assuntos
Cromatina/metabolismo , Biologia Molecular/métodos , Fatores de Transcrição/análise , Fatores de Transcrição/metabolismo , Animais , Histonas/metabolismo , Oócitos , Ligação Proteica/fisiologia , Relação Estrutura-Atividade , Xenopus
18.
Methods Mol Biol ; 287: 21-44, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15273401

RESUMO

Chromatin immunoprecipitation (ChIP) is a technique widely used for determining the genomic location of modified histones and other chromatin-associated factors. Here we describe the methodology we have used in our laboratory for the immunoprecipitation of chromatin isolated from cells in the absence of crosslinking. Chromatin released from nuclei by micrococcal nuclease digestion is centrifuged through sucrose gradients to allow selection of mono- or dinucleosomes. This allows a protein or modification at a particular gene or locus to be mapped at higher resolution than in a crosslinked ChIP experiment. Two methods for the immunoprecipitation of chromatin are described: a large-scale fractionation by which it is possible to visualize the proteins of the immunoprecipitate by polyacrylamide gel electrophoresis, PAGE and a small-scale method that is more appropriate when the quantity of chromatin is limited. The sequence content of DNA extracted from the immunoprecipitated chromatin is analyzed by hybridization of Southern or slot blots, or by quantitative polymerase chain reaction. Enrichment of particular sequences in the immunoprecipitated fraction reveals the presence and extent of the modification at this location.


Assuntos
Cromatina/química , Cromatina/isolamento & purificação , Testes de Precipitina/métodos , Animais , Anticorpos/isolamento & purificação , Células Cultivadas , Galinhas/genética , Cromatina/imunologia , DNA/análise , Eritrócitos/química , Eritrócitos/fisiologia , Histonas/química , Humanos , Células K562 , Reação em Cadeia da Polimerase/métodos
20.
Suicide Life Threat Behav ; 41(1): 98-109, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21309828

RESUMO

This article presents a sociologically informed critique of a range of academic literatures relating to self-injury. It is noted how a lack of consensus on definitional issues, together with the inaccurate portrayal of the "typical self-injurer" in the clinical literature, has impeded the development of a sound understanding of self-injury. Some of the more problematic explanations for self-injury are explored. The individualistic focus of existing research is found to be inadequate, since it fails to account for the social context in which self-injury occurs. Social scientific approaches critically examine psychiatric and psychological constructions of self-injury, explore wider social and cultural meanings of the behavior, and examine its distribution across different social groups. The inclusion of social scientific perspectives into current debates will greatly improve understanding of self-injury.


Assuntos
Comportamento Autodestrutivo/psicologia , Sociologia , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Automutilação/classificação , Automutilação/psicologia , Comportamento Autodestrutivo/classificação , Fatores Sexuais , Sexualidade/psicologia , Classe Social , Suicídio/classificação , Suicídio/psicologia , Terminologia como Assunto , Adulto Jovem
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