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1.
Br J Dermatol ; 172(5): 1338-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25627783

RESUMO

BACKGROUND: Lifestyle has been proven to have a dramatic effect on the risk of age-related diseases. The association of lifestyle and facial ageing has been less well studied. OBJECTIVES: To identify lifestyle factors that associate with perceived facial age in white north European men and women. METHODS: Lifestyle, facial wrinkling and perceived facial age were studied in two cross-sectional studies consisting of 318 Dutch men and 329 women aged 45-75 years who were part of the Leiden Longevity Study, and 162 English women aged 45-75 years who were nonsmokers. RESULTS: In Dutch men, smoking, having skin that went red in the sun, being outside in the sun most of the summer, sunbed use, wearing false teeth and not flossing teeth were all significantly associated (P < 0·05) with a total 9·3-year higher perceived facial age in a multivariate model adjusting for chronological age. In Dutch women, smoking, sunbathing, sunbed use, few remaining teeth and a low body mass index (BMI) were associated with a total 10·9-year higher perceived facial age. In English women, cleaning teeth only once a day, wearing false teeth, irregular skin moisturization and having skin that went red in the sun were associated with a total 9·1-year higher perceived facial age. Smoking and sunbed use were associated more strongly with wrinkling in women than in men. BMI, sun exposure and skincare were associated predominantly with perceived facial age via wrinkling, whereas oral care was associated via other facial features. CONCLUSIONS: Although associative in nature, these results support the notion that lifestyle factors can have long-term beneficial effects on youthful looks.


Assuntos
Imagem Corporal/psicologia , Face , Estilo de Vida , Envelhecimento da Pele/etnologia , Idoso , Estudos Transversais , Inglaterra/etnologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos/etnologia , Percepção , Caracteres Sexuais , População Branca/etnologia
2.
Br J Nutr ; 106(12): 1880-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21736785

RESUMO

Regular consumption of green tea may be cardioprotective. In the present study we investigated the health effects of dietary supplementation with green tea catechins and the potential modifying effect of the catechol-O-methyltransferase (COMT) Val/Met genotype. Subjects (sedentary males, aged 40-69 years, with BMI ≥ 28 and ≤ 38 kg/m(2)) were randomly assigned to consume decaffeinated green tea extract (DGT; 530 mg containing about 400 mg total catechins/capsule, twice daily) and placebo in a complete cross-over design. Ambulatory blood pressure and biomarkers of metabolic function (cholesterol, TAG, glucose and insulin) were measured at weeks 0 and 6. Although a marked increase in the concentration of plasma epigallocatechin gallate (EGCG), urinary epigallocatechin (EGC) and urinary 4'-O-methyl EGC was found after DGT treatment, no effect on blood pressure or biomarkers of metabolic function was observed. However, a period × treatment interaction (P < 0·05) was detected for body-weight change. Despite a similar increase in estimated energy intake during intervention period 1, body weight decreased by 0·64 (sd 2·2) kg and increased by 0·53 (sd 1·9) kg in the DGT and placebo groups, respectively (P = 0·025), suggesting a protective effect of green tea catechins on weight gain. Additionally, the COMT Val/Met genotype influenced urinary accumulation of EGC and 4'-O-methyl EGC (P < 0·01). Mean concentrations were lower in individuals homozygous for the high-activity G-allele, possibly reflecting increased metabolic flux and a more rapid conversion to downstream metabolic species, compared with individuals carrying at least one copy of the low-activity A-allele. Additional studies are needed to confirm these findings and further explore the modifying effect of genotype.


Assuntos
Catequina/administração & dosagem , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Chá/química , Adulto , Idoso , Alelos , Sequência de Bases , Biomarcadores/sangue , Biomarcadores/urina , Cardiotônicos/administração & dosagem , Cardiotônicos/isolamento & purificação , Catequina/análogos & derivados , Catequina/sangue , Catequina/isolamento & purificação , Catequina/urina , Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/metabolismo , Estudos Cross-Over , Primers do DNA/genética , Método Duplo-Cego , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Obesidade/metabolismo , Sobrepeso/genética , Sobrepeso/metabolismo
3.
J Eur Acad Dermatol Venereol ; 24(3): 341-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19758262

RESUMO

BACKGROUND: Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. OBJECTIVE: To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. METHODS: Facial photographs were collected of 250 Chinese women, aged 25-70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. RESULTS: Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans-epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. CONCLUSIONS: We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population.


Assuntos
Envelhecimento/fisiologia , Face/fisiologia , Autoimagem , Envelhecimento da Pele/fisiologia , Adulto , Idoso , China , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade
4.
Psychoneuroendocrinology ; 34(10): 1486-94, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19520518

RESUMO

OBJECTIVES: The cortisol awakening rise (CAR) is defined as cortisol secretory activity in the first 45-60 min immediately post-awakening. It has been suggested that psychological factors may disrupt the normal awakening rise. Recent research has shown that psychological stress may influence the magnitude of the CAR, however the findings have been mixed. This study examined the impact of stress on the CAR and the diurnal mean in a sample of middle-aged women. METHOD: One hundred and eighteen healthy female participants who reported experiencing high or low stress were recruited. Salivary cortisol levels were measured immediately upon awakening (at 0, 15, 30, and 45 min) and at 3, 6, 9 and 12 h on two consecutive days. A number of metabolic and inflammatory biomarkers were also assessed together with measures of mood disturbance and health behaviour. RESULTS: The magnitude of the CAR, assessed by the area under the response curve (AURC) estimate, was significantly lower in the high stress group compared to the low stress group indicating that participants who experienced high stress secreted lower levels of cortisol. The effect was largely accounted for by differences 30 min after waking. The diurnal mean was also lower for the high stress group. Although participants in the high stress group had a slightly worse inflammatory profile, only low-density lipoprotein levels were found to be significantly higher, compared to the low stress group. Lifestyle indicators and mood were also found to be significantly poorer in the high stress group. CONCLUSIONS: The results suggest that psychological stress may be associated with a smaller cortisol awakening rise, a lower diurnal mean, poor lifestyle choices and high levels of psychological distress. These findings may have broader implications for future health risk and for an individual's ability to cope with imminent daily stressors and demands.


Assuntos
Hidrocortisona/metabolismo , Mediadores da Inflamação/sangue , Estresse Psicológico/metabolismo , Adulto , Afeto/fisiologia , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Colesterol/sangue , Ritmo Circadiano/fisiologia , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Interleucina-6/sangue , Pessoa de Meia-Idade , Fatores de Risco , Saliva/metabolismo , Fatores de Tempo , Triglicerídeos/sangue , Vigília/fisiologia
5.
Nature ; 404(6777): 515-8, 2000 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-10761922

RESUMO

One of the main mechanisms of messenger RNA degradation in eukaryotes occurs by deadenylation-dependent decapping which leads to 5'-to-3' decay. A family of Sm-like (Lsm) proteins has been identified, members of which contain the 'Sm' sequence motif, form a complex with U6 small nuclear RNA and are required for pre-mRNA splicing. Here we show that mutations in seven yeast Lsm proteins (Lsm1-Lsm7) also lead to inhibition of mRNA decapping. In addition, the Lsm1-Lsm7 proteins co-immunoprecipitate with the mRNA decapping enzyme (Dcp1), a decapping activator (Pat1/Mrt1) and with mRNA. This indicates that the Lsm proteins may promote decapping by interactions with the mRNA and the decapping machinery. In addition, the Lsm complex that functions in mRNA decay appears to be distinct from the U6-associated Lsm complex, indicating that Lsm proteins form specific complexes that affect different aspects of mRNA metabolism.


Assuntos
Endorribonucleases , Proteínas Fúngicas/metabolismo , Capuzes de RNA , RNA Fúngico/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Saccharomyces cerevisiae , Autoantígenos/química , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Mutação , Proteínas de Ligação ao Cap de RNA , Estabilidade de RNA , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas Nucleares Pequenas/química , Saccharomyces cerevisiae , Técnicas do Sistema de Duplo-Híbrido , Proteínas Centrais de snRNP
6.
EMBO J ; 18(15): 4321-31, 1999 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-10428970

RESUMO

Seven Sm proteins associate with U1, U2, U4 and U5 spliceosomal snRNAs and influence snRNP biogenesis. Here we describe a novel set of Sm-like (Lsm) proteins in Saccharomyces cerevisiae that interact with each other and with U6 snRNA. Seven Lsm proteins co-immunoprecipitate with the previously characterized Lsm4p (Uss1p) and interact with each other in two-hybrid analyses. Free U6 and U4/U6 duplexed RNAs co-immunoprecipitate with seven of the Lsm proteins that are essential for the stable accumulation of U6 snRNA. Analyses of U4/U6 di-snRNPs and U4/U6.U5 tri-snRNPs in Lsm-depleted strains suggest that Lsm proteins may play a role in facilitating conformational rearrangements of the U6 snRNP in the association-dissociation cycle of spliceosome complexes. Thus, Lsm proteins form a complex that differs from the canonical Sm complex in its RNA association(s) and function. We discuss the possible existence and functions of alternative Lsm complexes, including the likelihood that they are involved in processes other than pre-mRNA splicing.


Assuntos
RNA Nuclear Pequeno/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Testes de Precipitina , Splicing de RNA , RNA Nuclear Pequeno/genética , Proteínas Recombinantes de Fusão/metabolismo , Ribonucleoproteínas Nucleares Pequenas/química , Homologia de Sequência de Aminoácidos
7.
RNA ; 5(11): 1470-81, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10580475

RESUMO

Through a combination of in vitro snRNP reconstitution, photocross-linking and immunoprecipitation techniques, we have investigated the interaction of proteins with the spliceosomal U6 snRNA in U6 snRNPs, U4/U6 di-snRNPs and U4/U6.U5 tri-snRNPs. Of the seven Lsm (Sm-like) proteins that associate specifically with this spliceosomal snRNA, three were shown to contact the RNA directly, and to maintain contact as the U6 RNA is incorporated into tri-snRNPs. In tri-snRNPs, the U5 snRNP protein Prp8 contacts position 54 of U6, which is in the conserved region that contributes to the formation of the catalytic core of the spliceosome. Other tri-snRNP-specific contacts were also detected, indicating the dynamic nature of protein interactions with this important snRNA. The uridine-rich extreme 3' end of U6 RNA was shown to be essential but not sufficient for the association of the Lsm proteins. Interestingly, the Lsm proteins associate efficiently with the 3' half of U6, which contains the 3' stem-loop and uridine-rich 3' end, suggesting that the Lsm and Sm proteins may recognize similar features in RNAs.


Assuntos
RNA Nuclear Pequeno/química , RNA Nuclear Pequeno/metabolismo , Ribonucleoproteína Nuclear Pequena U4-U6/química , Ribonucleoproteína Nuclear Pequena U4-U6/metabolismo , Sequência de Bases , Sequência Conservada , Reagentes de Ligações Cruzadas , Escherichia coli/genética , Oligodesoxirribonucleotídeos/química , RNA Bacteriano/química , RNA Bacteriano/efeitos da radiação , RNA de Transferência/química , RNA de Transferência/efeitos da radiação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Spliceossomos/metabolismo , Raios Ultravioleta
8.
Yeast ; 17(2): 95-110, 2000 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10900456

RESUMO

A set of seven structurally related Sm proteins forms the core of the snRNP particles containing the spliceosomal U1, U2, U4 and U5 snRNAs. A search of the genomic sequence of Saccharomyces cerevisiae has identified a number of open reading frames that potentially encode structurally similar proteins termed Lsm (Like Sm) proteins. With the aim of analysing all possible interactions between the Lsm proteins and any protein encoded in the yeast genome, we performed exhaustive and iterative genomic two-hybrid screens, starting with the Lsm proteins as baits. Indeed, extensive interactions amongst eight Lsm proteins were found that suggest the existence of a Lsm complex or complexes. These Lsm interactions apparently involve the conserved Sm domain that also mediates interactions between the Sm proteins. The screens also reveal functionally significant interactions with splicing factors, in particular with Prp4 and Prp24, compatible with genetic studies and with the reported association of Lsm proteins with spliceosomal U6 and U4/U6 particles. In addition, interactions with proteins involved in mRNA turnover, such as Mrt1, Dcp1, Dcp2 and Xrn1, point to roles for Lsm complexes in distinct RNA metabolic processes, that are confirmed in independent functional studies. These results provide compelling evidence that two-hybrid screens yield functionally meaningful information about protein-protein interactions and can suggest functions for uncharacterized proteins, especially when they are performed on a genome-wide scale.


Assuntos
Proteínas Fúngicas/metabolismo , Genoma Fúngico , RNA Mensageiro/metabolismo , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Saccharomyces cerevisiae/genética , Proteínas Fúngicas/genética , Proteoma/análise , Splicing de RNA , RNA Fúngico/metabolismo , Ribonucleoproteínas Nucleares Pequenas/genética , Saccharomyces cerevisiae/metabolismo , Técnicas do Sistema de Duplo-Híbrido
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