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2.
PLoS Pathog ; 18(7): e1010631, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35816514

RESUMO

The S:A222V point mutation, within the G clade, was characteristic of the 20E (EU1) SARS-CoV-2 variant identified in Spain in early summer 2020. This mutation has since reappeared in the Delta subvariant AY.4.2, raising questions about its specific effect on viral infection. We report combined serological, functional, structural and computational studies characterizing the impact of this mutation. Our results reveal that S:A222V promotes an increased RBD opening and slightly increases ACE2 binding as compared to the parent S:D614G clade. Finally, S:A222V does not reduce sera neutralization capacity, suggesting it does not affect vaccine effectiveness.


Assuntos
COVID-19 , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/genética , COVID-19/genética , Patrimônio Genético , Humanos , Mutação , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
Arch Biochem Biophys ; 754: 109943, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395125

RESUMO

The small, 78-residue long, regulator SipA interacts with the non-bleaching sensor histidine kinase (NblS). We have solved the solution structure of SipA on the basis of 990 nuclear Overhauser effect- (NOE-) derived distance constraints. The average pairwise root-mean-square deviation (RMSD) for the twenty best structures for the backbone residues, obtained by CYANA, was 1.35 ± 0.21 Å, and 1.90 ± 0.16 Å when all heavy atoms were considered (the target function of CYANA was 0.540 ± 0.08). The structure is that of a ß-II class protein, basically formed by a five-stranded ß-sheet composed of antiparallel strands following the arrangement: Gly6-Leu11 (ß-strand 1), which packs against Leu66-Val69 (ß-strand 5) on one side, and against Gly36-Thr42 (ß-strand 2) on the other side; Trp50-Phe54 (ß-strand 3); and Gly57-Leu60 (ß-strand 4). The protein is highly mobile, as shown by measurements of R1, R2, NOE and ηxy relaxation parameters, with an average order parameter () of 0.70; this mobility encompasses movements in different time scales. We hypothesize that this high flexibility allows the interaction with other proteins (among them NblS), and it explains the large conformational stability of SipA.

4.
Proc Natl Acad Sci U S A ; 115(12): 3042-3047, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29507252

RESUMO

YiiP is a dimeric antiporter from the cation diffusion facilitator family that uses the proton motive force to transport Zn2+ across bacterial membranes. Previous work defined the atomic structure of an outward-facing conformation, the location of several Zn2+ binding sites, and hydrophobic residues that appear to control access to the transport sites from the cytoplasm. A low-resolution cryo-EM structure revealed changes within the membrane domain that were associated with the alternating access mechanism for transport. In the current work, the resolution of this cryo-EM structure has been extended to 4.1 Å. Comparison with the X-ray structure defines the differences between inward-facing and outward-facing conformations at an atomic level. These differences include rocking and twisting of a four-helix bundle that harbors the Zn2+ transport site and controls its accessibility within each monomer. As previously noted, membrane domains are closely associated in the dimeric structure from cryo-EM but dramatically splayed apart in the X-ray structure. Cysteine crosslinking was used to constrain these membrane domains and to show that this large-scale splaying was not necessary for transport activity. Furthermore, dimer stability was not compromised by mutagenesis of elements in the cytoplasmic domain, suggesting that the extensive interface between membrane domains is a strong determinant of dimerization. As with other secondary transporters, this interface could provide a stable scaffold for movements of the four-helix bundle that confers alternating access of these ions to opposite sides of the membrane.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/fisiologia , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/fisiologia , Sítios de Ligação , Microscopia Crioeletrônica , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Modelos Moleculares , Conformação Proteica , Domínios Proteicos
5.
Int J Cancer ; 144(2): 240-250, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29943826

RESUMO

The epidemiological evidence regarding the association of coffee and tea consumption with prostate cancer risk is inconclusive, and few cohort studies have assessed these associations by disease stage and grade. We examined the associations of coffee (total, caffeinated and decaffeinated) and tea intake with prostate cancer risk in the European Prospective Investigation into Cancer and Nutrition. Among 142,196 men, 7,036 incident prostate cancer cases were diagnosed over 14 years of follow-up. Data on coffee and tea consumption were collected through validated country-specific food questionnaires at baseline. We used Cox proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (CI). Models were stratified by center and age, and adjusted for anthropometric, lifestyle and dietary factors. Median coffee and tea intake were 375 and 106 mL/day, respectively, but large variations existed by country. Comparing the highest (median of 855 mL/day) versus lowest (median of 103 mL/day) consumers of coffee and tea (450 vs. 12 mL/day) the HRs were 1.02 (95% CI, 0.94-1.09) and 0.98 (95% CI, 0.90-1.07) for risk of total prostate cancer and 0.97 (95% CI, 0.79-1.21) and 0.89 (95% CI, 0.70-1.13) for risk of fatal disease, respectively. No evidence of association was seen for consumption of total, caffeinated or decaffeinated coffee or tea and risk of total prostate cancer or cancer by stage, grade or fatality in this large cohort. Further investigations are needed to clarify whether an association exists by different preparations or by concentrations and constituents of these beverages.


Assuntos
Café , Neoplasias da Próstata/epidemiologia , Chá , Adulto , Idoso , Estudos de Coortes , Inquéritos sobre Dietas , Europa (Continente) , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Risco
6.
Eur J Nutr ; 58(5): 2003-2010, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29905885

RESUMO

PURPOSE: Dietary guidelines for egg consumption for general population differ among public health agencies. Our aim was to investigate the association between egg intake and both all-cause and specific-cause of mortality in a Mediterranean population. METHODS: The European Prospective Investigation into Cancer and Nutrition (EPIC)-Spain cohort included 40,621 men and women aged 29-69 years old in the nineties from 5 Spanish regions. After a mean of 18 years of follow-up, 3,561 deaths were recorded, of which 1,694 were from cancer, 761 from CVD, and 870 from other causes. Data on egg consumption was collected using a validated diet history at recruitment. Cox proportional hazards models, adjusted for confounders, were used in the analyses. RESULTS: The mean (standard deviation) egg consumption was 22.0 g/day (15.8) and 30.9 g/day (23.1) in women and men, respectively. No association was observed between egg consumption and all-cause mortality for the highest vs the lowest quartile (HR 1.01; 95% CI 0.91-1.11; P trend = 0.96). Likewise, no association was observed with cancer and cardiovascular diseases mortality. However, an inverse association was found between egg consumption and deaths for other causes (HR 0.76; 95% CI 0.63-0.93; P trend = 0.003), particularly for deaths from the nervous system (HR 0.59; 95% CI 0.35-1.00; P trend = 0.036). No interaction was detected with the adherence to Mediterranean diet. CONCLUSIONS: This study shows no association between moderate egg consumption, up to 1 egg per day, and main causes of mortality in a large free-living Mediterranean population.


Assuntos
Ovos/estatística & dados numéricos , Inquéritos Epidemiológicos/estatística & dados numéricos , Mortalidade , Neoplasias/mortalidade , Adulto , Idoso , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Modelos de Riscos Proporcionais , Estudos Prospectivos , Espanha/epidemiologia , Inquéritos e Questionários
7.
J Biol Chem ; 292(40): 16594-16604, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28821608

RESUMO

The function of protein products generated from intramembraneous cleavage by the γ-secretase complex is not well defined. The γ-secretase complex is responsible for the cleavage of several transmembrane proteins, most notably the amyloid precursor protein that results in Aß, a transmembrane (TM) peptide. Another protein that undergoes very similar γ-secretase cleavage is the p75 neurotrophin receptor. However, the fate of the cleaved p75 TM domain is unknown. p75 neurotrophin receptor is highly expressed during early neuronal development and regulates survival and process formation of neurons. Here, we report that the p75 TM can stimulate the phosphorylation of TrkB (tyrosine kinase receptor B). In vitro phosphorylation experiments indicated that a peptide representing p75 TM increases TrkB phosphorylation in a dose- and time-dependent manner. Moreover, mutagenesis analyses revealed that a valine residue at position 264 in the rat p75 neurotrophin receptor is necessary for the ability of p75 TM to induce TrkB phosphorylation. Because this residue is just before the γ-secretase cleavage site, we then investigated whether the p75(αγ) peptide, which is a product of both α- and γ-cleavage events, could also induce TrkB phosphorylation. Experiments using TM domains from other receptors, EGFR and FGFR1, failed to stimulate TrkB phosphorylation. Co-immunoprecipitation and biochemical fractionation data suggested that p75 TM stimulates TrkB phosphorylation at the cell membrane. Altogether, our results suggest that TrkB activation by p75(αγ) peptide may be enhanced in situations where the levels of the p75 receptor are increased, such as during brain injury, Alzheimer's disease, and epilepsy.


Assuntos
Membrana Celular/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptor de Fator de Crescimento Neural/metabolismo , Receptor trkB/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Substituição de Aminoácidos , Animais , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Membrana Celular/genética , Epilepsia/genética , Epilepsia/metabolismo , Humanos , Glicoproteínas de Membrana/genética , Mutagênese , Mutação de Sentido Incorreto , Fosforilação , Domínios Proteicos , Ratos , Receptor de Fator de Crescimento Neural/genética , Receptor trkB/genética , Células Sf9 , Spodoptera
8.
Breast Cancer Res ; 17: 15, 2015 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-25637171

RESUMO

INTRODUCTION: Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer. METHODS: A total of 335,060 women participating in the European Prospective Investigation into Nutrition and Cancer (EPIC) Study, completed a dietary questionnaire from 1992 to 2000, and were followed-up until 2010 for incidence of breast cancer. Hazard ratios (HR) of breast cancer by country-specific, as well as cohort-wide categories of beverage intake were estimated. RESULTS: During an average follow-up of 11 years, 1064 premenopausal, and 9134 postmenopausal breast cancers were diagnosed. Caffeinated coffee intake was associated with lower risk of postmenopausal breast cancer: adjusted HR=0.90, 95% confidence interval (CI): 0.82 to 0.98, for high versus low consumption; Ptrend=0.029. While there was no significant effect modification by hormone receptor status (P=0.711), linear trend for lower risk of breast cancer with increasing caffeinated coffee intake was clearest for estrogen and progesterone receptor negative (ER-PR-), postmenopausal breast cancer (P=0.008). For every 100 ml increase in caffeinated coffee intake, the risk of ER-PR- breast cancer was lower by 4% (adjusted HR: 0.96, 95% CI: 0.93 to 1.00). Non-consumers of decaffeinated coffee had lower risk of postmenopausal breast cancer (adjusted HR=0.89; 95% CI: 0.80 to 0.99) compared to low consumers, without evidence of dose-response relationship (Ptrend=0.128). Exclusive decaffeinated coffee consumption was not related to postmenopausal breast cancer risk, compared to any decaffeinated-low caffeinated intake (adjusted HR=0.97; 95% CI: 0.82 to 1.14), or to no intake of any coffee (HR: 0.96; 95%: 0.82 to 1.14). Caffeinated and decaffeinated coffee were not associated with premenopausal breast cancer. Tea intake was neither associated with pre- nor post-menopausal breast cancer. CONCLUSIONS: Higher caffeinated coffee intake may be associated with lower risk of postmenopausal breast cancer. Decaffeinated coffee intake does not seem to be associated with breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Café , Menopausa , Chá , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Sistema de Registros , Medição de Risco , Fatores de Risco , Inquéritos e Questionários
9.
Eur J Epidemiol ; 29(9): 639-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25154553

RESUMO

Consumption of fruits and vegetables is associated with a lower overall mortality. The aim of this study was to identify causes of death through which this association is established. More than 450,000 participants from the European Prospective Investigation into Cancer and Nutrition study were included, of which 25,682 were reported deceased after 13 years of follow-up. Information on lifestyle, diet and vital status was collected through questionnaires and population registries. Hazard ratios (HR) with 95% confidence intervals (95% CI) for death from specific causes were calculated from Cox regression models, adjusted for potential confounders. Participants reporting consumption of more than 569 g/day of fruits and vegetables had lower risks of death from diseases of the circulatory (HR for upper fourth 0.85, 95% CI 0.77-0.93), respiratory (HR for upper fourth 0.73, 95% CI 0.59-0.91) and digestive system (HR for upper fourth 0.60, 95% CI 0.46-0.79) when compared with participants consuming less than 249 g/day. In contrast, a positive association with death from diseases of the nervous system was observed. Inverse associations were generally observed for vegetable, but not for fruit consumption. Associations were more pronounced for raw vegetable consumption, when compared with cooked vegetable consumption. Raw vegetable consumption was additionally inversely associated with death from neoplasms and mental and behavioral disorders. The lower risk of death associated with a higher consumption of fruits and vegetables may be derived from inverse associations with diseases of the circulatory, respiratory and digestive system, and may depend on the preparation of vegetables and lifestyle factors.


Assuntos
Causas de Morte , Inquéritos sobre Dietas/estatística & dados numéricos , Comportamento Alimentar , Frutas , Verduras , Adulto , Idoso , Doenças Cardiovasculares/mortalidade , Dieta , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários
10.
Biochim Biophys Acta ; 1819(5): 382-90, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22306661

RESUMO

Cyanobacteria respond to environmental stress conditions by adjusting their photosynthesis machinery. In Synechococcus sp. PCC 7942, phycobilisome degradation and other acclimation responses after nutrient or high light stress require activation by the phosphorylation-independent response regulator NblR. Structural modelling of its receiver domain suggested a role for Cys69 and Cys96 on activation of NblR. Here, we investigate this hypothesis by engineering Cys to Ala substitutions. In vivo and in vitro analyses indicated that mutations Cys69Ala and/or Cys96Ala have a minor impact on NblR function, structure, size, or oligomerization state of the protein, and that Cys69 and Cys96 do not seem to form disulphide bridges. Our results argue against the predicted involvement of Cys69 and Cys96 on NblR activation by redox sensing.


Assuntos
Alanina , Proteínas de Bactérias/química , Cisteína , Fotossíntese , Fatores de Transcrição/química , Alanina/genética , Alanina/fisiologia , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Substituição de Aminoácidos/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Cisteína/genética , Cisteína/fisiologia , Regulação Bacteriana da Expressão Gênica , Luz , Oxirredução , Fosforilação , Fotossíntese/genética , Fotossíntese/fisiologia , Ficobilissomas/genética , Ficobilissomas/fisiologia , Conformação Proteica , Alinhamento de Sequência , Estresse Fisiológico , Synechococcus/genética , Synechococcus/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia
11.
Int J Cancer ; 132(9): 2164-75, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23015357

RESUMO

Menstrual and reproductive factors and exogenous hormone use have been investigated as pancreatic cancer risk factors in case-control and cohort studies, but results have been inconsistent. We conducted a prospective examination of menstrual and reproductive factors, exogenous hormone use and pancreatic cancer risk (based on 304 cases) in 328,610 women from the EPIC cohort. Then, in a case-control study nested within the EPIC cohort, we examined 12 single nucleotide polymorphisms (SNPs) in CYP17A1 (an essential gene in sex steroid metabolism) for association with pancreatic cancer in women and men (324 cases and 353 controls). Of all factors analyzed, only younger age at menarche (<12 vs. 13 years) was moderately associated with an increased risk of pancreatic cancer in the full cohort; however, this result was marginally significant (HR = 1.44; 95% CI = 0.99-2.10). CYP17A1 rs619824 was associated with HRT use (p value = 0.037) in control women; however, none of the SNPs alone, in combination, or as haplotypes were associated with pancreatic cancer risk. In conclusion, with the possible exception of an early age of menarche, none of the menstrual and reproductive factors, and none of the 12 common genetic variants we evaluated at the CYP17A1 locus makes a substantial contribution to pancreatic cancer susceptibility in the EPIC cohort.


Assuntos
Adenocarcinoma/etiologia , Neoplasias Pancreáticas/etiologia , Polimorfismo de Nucleotídeo Único/genética , Esteroide 17-alfa-Hidroxilase/genética , Adulto , Estudos de Casos e Controles , Feminino , Seguimentos , Genótipo , Haplótipos/genética , Humanos , Masculino , Menstruação , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , História Reprodutiva , Fatores de Risco
12.
Am J Epidemiol ; 177(8): 787-99, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23492765

RESUMO

A "Western" lifestyle characterized by physical inactivity and excess weight is associated with a number of metabolic and hormonal dysregulations, including increased circulating estrogen levels, hyperinsulinemia, hyperglycemia, and chronic inflammation. The same hormonal and metabolic axes might mediate the association between this lifestyle and the development of endometrial cancer. Using data collected within the European Prospective Investigation into Cancer and Nutrition (EPIC), a prospective cohort study carried out in 10 European countries during 1992-2000, we conducted a factor analysis to delineate important components that summarize the variation explained by a set of biomarkers and to examine their association with endometrial cancer risk. Prediagnostic levels of testosterone, androstenedione, dehydroepiandrosterone sulfate, sex hormone-binding globulin, estrone, estradiol, C-peptide, insulin-like growth factor-binding proteins 1 and 2, adiponectin, high- and low-density lipoprotein cholesterol, glucose, triglycerides, tumor necrosis factor (TNF) α, soluble TNF receptors 1 and 2, C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist were measured in 233 incident endometrial cancer cases and 446 matched controls. Factor analysis identified 3 components associated with postmenopausal endometrial cancer risk that could be labeled "insulin resistance/metabolic syndrome," "steroids," and "inflammation" factors. A fourth component, "lipids," was not significantly associated with endometrial cancer. In conclusion, besides the well-known associations of risk with sex hormones and insulin-regulated physiological axes, our data further support the hypothesis that inflammation factors play a role in endometrial carcinogenesis.


Assuntos
Biomarcadores/sangue , Neoplasias do Endométrio/epidemiologia , Inflamação/sangue , Adiponectina/sangue , Idoso , Glicemia/metabolismo , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Colesterol/sangue , Estudos de Coortes , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/etiologia , Estrogênios/sangue , União Europeia/estatística & dados numéricos , Análise Fatorial , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Incidência , Inflamação/epidemiologia , Interleucina-1/sangue , Interleucina-6/sangue , Estilo de Vida , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Somatomedinas/metabolismo , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue , Circunferência da Cintura
13.
Am J Epidemiol ; 178(4): 590-602, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23599238

RESUMO

In this study, the relation between fruit and vegetable consumption and mortality was investigated within the European Prospective Investigation Into Cancer and Nutrition. Survival analyses were performed, including 451,151 participants from 10 European countries, recruited between 1992 and 2000 and followed until 2010. Hazard ratios, rate advancement periods, and preventable proportions to respectively compare risk of death between quartiles of consumption, to estimate the period by which the risk of death was postponed among high consumers, and to estimate proportions of deaths that could be prevented if all participants would shift their consumption 1 quartile upward. Consumption of fruits and vegetables was inversely associated with all-cause mortality (for the highest quartile, hazard ratio = 0.90, 95% confidence interval (CI): 0.86, 0.94), with a rate advancement period of 1.12 years (95% CI: 0.70, 1.54), and with a preventable proportion of 2.95%. This association was driven mainly by cardiovascular disease mortality (for the highest quartile, hazard ratio = 0.85, 95% CI: 0.77, 0.93). Stronger inverse associations were observed for participants with high alcohol consumption or high body mass index and suggested in smokers. Inverse associations were stronger for raw than for cooked vegetable consumption. These results support the evidence that fruit and vegetable consumption is associated with a lower risk of death.


Assuntos
Inquéritos sobre Dietas/estatística & dados numéricos , Frutas , Neoplasias/mortalidade , Verduras , Adulto , Idoso , Causas de Morte , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de Sobrevida
14.
Br J Nutr ; 110(2): 363-74, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23228223

RESUMO

Different lifestyle patterns across Europe may influence plasma concentrations of B-vitamins and one-carbon metabolites and their relation to chronic disease. Comparison of published data on one-carbon metabolites in Western European regions is difficult due to differences in sampling procedures and analytical methods between studies. The present study aimed, to compare plasma concentrations of one-carbon metabolites in Western European regions with one laboratory performing all biochemical analyses. We performed the present study in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort among 5446 presumptively healthy individuals. Quantile regression was used to compare sex-specific median concentrations between Northern (Denmark and Sweden), Central (France, Germany, The Netherlands and United Kingdom) and Southern (Greece, Spain and Italy) European regions. The lowest folate concentrations were observed in Northern Europe (men, 10·4 nmol/l; women, 10·7 nmol/l) and highest concentrations in Central Europe. Cobalamin concentrations were slightly higher in Northern Europe (men, 330 pmol/l; women, 352 pmol/l) compared with Central and Southern Europe, but did not show a clear north-south gradient. Vitamin B2 concentrations were highest in Northern Europe (men, 22·2 nmol/l; women, 26·0 nmol/l) and decreased towards Southern Europe (P trend< 0·001). Vitamin B(6) concentrations were highest in Central Europe in men (77·3 nmol/l) and highest in the North among women (70·4 nmol/l), with decreasing concentrations towards Southern Europe in women (P trend< 0·001). In men, concentrations of serine, glycine and sarcosine increased from the north to south. In women, sarcosine increased from Northern to Southern Europe. These findings may provide relevant information for the study of regional differences of chronic disease incidence in association with lifestyle.


Assuntos
Ácido Fólico/sangue , Glicina/sangue , Comportamentos Relacionados com a Saúde/etnologia , Estilo de Vida/etnologia , Sarcosina/sangue , Serina/sangue , Vitamina B 12/sangue , Adulto , Idoso , Consumo de Bebidas Alcoólicas/etnologia , Doença Crônica/etnologia , Etnicidade , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores Sexuais , Fumar/etnologia
15.
J Med Chem ; 66(15): 10432-10457, 2023 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-37471688

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, by infecting cells via the interaction of its spike protein (S) with the primary cell receptor angiotensin-converting enzyme (ACE2). To search for inhibitors of this key step in viral infection, we screened an in-house library of multivalent tryptophan derivatives. Using VSV-S pseudoparticles, we identified compound 2 as a potent entry inhibitor lacking cellular toxicity. Chemical optimization of 2 rendered compounds 63 and 65, which also potently inhibited genuine SARS-CoV-2 cell entry. Thermofluor and microscale thermophoresis studies revealed their binding to S and to its isolated receptor binding domain (RBD), interfering with the interaction with ACE2. High-resolution cryoelectron microscopy structure of S, free or bound to 2, shed light on cell entry inhibition mechanisms by these compounds. Overall, this work identifies and characterizes a new class of SARS-CoV-2 entry inhibitors with clear potential for preventing and/or fighting COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Triptofano/farmacologia , Triptofano/metabolismo , Enzima de Conversão de Angiotensina 2/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Microscopia Crioeletrônica , Ligação Proteica
16.
Br J Nutr ; 108(11): 2075-82, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23006416

RESUMO

Olive oil is well known for its cardioprotective properties; however, epidemiological data showing that olive oil consumption reduces incident CHD events are still limited. Therefore, we studied the association between olive oil and CHD in the European Prospective Investigation into Cancer and Nutrition (EPIC) Spanish cohort study. The analysis included 40 142 participants (38 % male), free of CHD events at baseline, recruited from five EPIC-Spain centres from 1992 to 1996 and followed up until 2004. Baseline dietary and lifestyle information was collected using interview-administered questionnaires. Cox proportional regression models were used to assess the relationship between validated incident CHD events and olive oil intake (energy-adjusted quartiles and each 10 g/d per 8368 kJ (2000 kcal) increment), while adjusting for potential confounders. During a 10·4-year follow-up, 587 (79 % male) CHD events were recorded. Olive oil intake was negatively associated with CHD risk after excluding dietary mis-reporters (hazard ratio (HR) 0·93; 95 % CI 0·87, 1·00 for each 10 g/d per 8368 kJ (2000 kcal) and HR 0·78; 95 % CI 0·59, 1·03 for upper v. lower quartile). The inverse association between olive oil intake (per 10 g/d per 8368 kJ (2000 kcal)) and CHD was more pronounced in never smokers (11 % reduced CHD risk (P = 0·048)), in never/low alcohol drinkers (25 % reduced CHD risk (P < 0·001)) and in virgin olive oil consumers (14 % reduced CHD risk (P = 0·072)). In conclusion, olive oil consumption was related to a reduced risk of incident CHD events. This emphasises the need to conserve the traditional culinary use of olive oil within the Mediterranean diet to reduce the CHD burden.


Assuntos
Cardiotônicos/uso terapêutico , Doença das Coronárias/prevenção & controle , Gorduras Insaturadas na Dieta/uso terapêutico , Frutas/química , Olea/química , Óleos de Plantas/uso terapêutico , Adulto , Idoso , Cardiotônicos/administração & dosagem , Estudos de Coortes , Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Gorduras Insaturadas na Dieta/administração & dosagem , Feminino , Seguimentos , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Azeite de Oliva , Óleos de Plantas/administração & dosagem , Modelos de Riscos Proporcionais , Estudos Prospectivos , Risco , Espanha/epidemiologia
17.
Int J Cancer ; 129(8): 2032-7, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21154749

RESUMO

Chronic inflammation has been hypothesized to play a role in endometrial cancer development. Tumor necrosis factor-α (TNF-α), one of the major pro-inflammatory cytokines, has also been implicated in endometrial physiology. We conducted a case-control study nested within the European prospective investigation into cancer and nutrition (EPIC) to examine the association of TNF-α and its two soluble receptors (sTNFR1 and sTNFR2) with endometrial cancer risk. Two-hundred-seventy cases and 518 matched controls were analyzed using conditional logistic regression. All statistical tests were two-sided. We observed an increased risk of endometrial cancer among women in the highest versus lowest quartile of TNF-α (odds ratio [OR]: 1.73, 95% CI: 1.09-2.73, P(trend) = 0.01), sTNFR1 (OR: 1.68, 95% CI: 0.99-2.86, P(trend) = 0.07) and sTNFR2 (OR: 1.53, 95%CI: 0.92-2.55, P(trend) = 0.03) after adjustment for body-mass-index, parity, age at menopause and previous postmenopausal hormone therapy use. Further adjustments for estrogens and C-peptide had minor effect on risk estimates. Our data show that elevated prediagnostic concentrations of TNF-α and its soluble receptors are related to a higher risk of endometrial cancer, particularly strong in women diagnosed within 2 years of blood donation. This is the first study of its kind and therefore deserves replication in further prospective studies.


Assuntos
Neoplasias do Endométrio/sangue , Receptores do Fator de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/sangue , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Risco
18.
Mol Microbiol ; 78(2): 475-89, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20979345

RESUMO

NblS, the most conserved histidine kinase in cyanobacteria, regulates photosynthesis and acclimatization to a variety of environmental conditions. We used in silico, in vivo and in vitro approaches to identify RpaB and SrrA as the cognate response regulators of NblS and to characterize relevant interactions between components of this signalling system. While genetic analysis showed the importance of the NblS to RpaB phosphorylation branch for culture viability in Synechococcus elongatus PCC 7942, in vitro assays indicated a strong preference for NblS to phosphorylate SrrA. This apparent discrepancy can be explained by environmental insulation of the RpaB pathway, achieved by RpaB-dependent repression of srrA under standard, low light culture conditions. After a strong but transient increase in srrA expression upon high light exposure, negative regulation of srrA and other high light inducible genes takes place, suggesting cooperation between pathways under environmental conditions in which both RpaB and SrrA are present. Complex regulatory interactions between RpaB and SrrA, two response regulators with a common evolutionary origin that are controlled by a single histidine kinase, are thus emerging. Our results provide a paradigm for regulatory interactions between response regulators in a branched two-component system.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Synechococcus/genética , Aclimatação , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Histidina Quinase , Luz , Viabilidade Microbiana , Fosforilação , Mutação Puntual , Proteínas Quinases/genética , Regulon , Synechococcus/metabolismo , Synechococcus/efeitos da radiação
19.
Br J Nutr ; 106(10): 1581-91, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21736834

RESUMO

Epidemiological studies show that adherence to a Mediterranean diet (MD) increases longevity; however, few studies are restricted to Mediterranean populations or explore the effect of a MD pattern that directly incorporates olive oil. Therefore the relationship between adherence to the MD and mortality was studied within the the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Spain). The EPIC-Spain analysis included 40 622 participants (37·7 % males) aged 29-69 years who were recruited from five Spanish regions in 1992-1996. During a mean follow-up of 13·4 years, 1855 deaths were documented: 913 from cancer, 399 from CVD, 425 from other causes and 118 from unknown causes of death. Risk of all-cause and cause-specific mortality was assessed according to the level of adherence to a relative MD (rMED) score, measured using an 18-unit scale incorporating nine selected dietary components. A high compared with a low rMED score was associated with a significant reduction in mortality from all causes (hazard ratio (HR) 0·79; 95 % CI 0·69, 0·91), from CVD (HR 0·66; 95 % CI 0·49, 0·89), but not from overall cancer (HR 0·92; 95 % CI 0·75, 1·12). A 2-unit increase in rMED score was associated with a 6 % (P < 0·001) decreased risk of all-cause mortality. A high olive oil intake and moderate alcohol consumption contributed most to this association. In this Spanish cohort, following an olive oil-rich MD was related to a significant reduction in all-cause mortality, and reduced the risk of mortality from CVD. These results support the important role that the MD pattern has on reducing mortality in Mediterranean countries.


Assuntos
Dieta Mediterrânea , Fidelidade a Diretrizes , Mortalidade , Adulto , Idoso , Estudos de Coortes , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Espanha/epidemiologia
20.
Int J Cancer ; 127(10): 2402-11, 2010 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20162568

RESUMO

The carcinogenicity of cigar and pipe smoking is established but the effect of detailed smoking characteristics is less well defined. We examined the effects on cancer incidence of exclusive cigar and pipe smoking, and in combination with cigarettes, among 102,395 men from Denmark, Germany, Spain, Sweden and the United Kingdom in the EPIC cohort. Hazard ratios (HR) and their 95% confidence intervals (CI) for cancer during a median 9-year follow-up from ages 35 to 70 years were estimated using proportional hazards models. Compared to never smokers, HR of cancers of lung, upper aerodigestive tract and bladder combined was 2.2 (95% CI: 1.3, 3.8) for exclusive cigar smokers (16 cases), 3.0 (2.1, 4.5) for exclusive pipe smokers (33 cases) and 5.3 (4.4, 6.4) for exclusive cigarette smokers (1,069 cases). For each smoking type, effects were stronger in current smokers than in ex-smokers and in inhalers than in non-inhalers. Ever smokers of both cigarettes and cigars [HR 5.7 (4.4, 7.3), 120 cases] and cigarettes and pipes [5.1 (4.1, 6.4), 247 cases] had as high a raised risk as had exclusive cigarette smokers. In these smokers, the magnitude of the raised risk was smaller if they had switched to cigars or pipes only (i.e., quit cigarettes) and had not compensated with greater smoking intensity. Cigar and pipe smoking is not a safe alternative to cigarette smoking. The lower cancer risk of cigar and pipe smokers as compared to cigarette smokers is explained by lesser degree of inhalation and lower smoking intensity.


Assuntos
Neoplasias/epidemiologia , Fumar/epidemiologia , Adulto , Idoso , Estudos de Coortes , Europa (Continente)/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fumar/efeitos adversos
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