Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
1.
Molecules ; 28(20)2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37894660

RESUMO

Type 2 diabetes mellitus and diabetic foot ulcers remain serious worldwide health problems. Caffeic acid is one of the natural products that has been experimentally proven to have diverse pharmacological properties. This study aimed to assess the inhibitory activity of caffeic acid and ethanolic extract of spent coffee grounds targeting DPP-4 and MMP-9 enzymes and evaluate the molecular interactions through 50-ns molecular dynamics simulations. This study also introduced our new version of PyPLIF HIPPOS, PyPLIF HIPPOS 0.2.0, which allowed us to identify protein-ligand interaction fingerprints and interaction hotspots resulting from molecular dynamics simulations. Our findings revealed that caffeic acid inhibited the DPP-4 and MMP-9 activity with an IC50 of 158.19 ± 11.30 µM and 88.99 ± 3.35 µM while ethanolic extract of spent coffee grounds exhibited an IC50 of 227.87 ± 23.80 µg/100 µL and 81.24 ± 6.46 µg/100 µL, respectively. Molecular dynamics simulations showed that caffeic acid interacted in the plausible allosteric sites of DPP-4 and in the active site of MMP-9. PyPLIF HIPPOS 0.2.0 identified amino acid residues interacting more than 10% throughout the simulation, which were Lys463 and Trp62 in the plausible allosteric site of DPP-4 and His226 in the active site of MMP-9.


Assuntos
Café , Diabetes Mellitus Tipo 2 , Humanos , Café/química , Metaloproteinase 9 da Matriz , Etanol , Extratos Vegetais/farmacologia
2.
Environ Monit Assess ; 195(10): 1211, 2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37707663

RESUMO

The hypothesis that local hypoxia and chlorophyll concentration are spatially tethered to local, sediment-driven nutrient release was examined in a small, nutrient-impacted estuary in the Southern Gulf of St. Lawrence, Canada. Sediment reactor core samples were taken at 10 locations between 0.25 and 100% of the estuary area in spring and fall (2019) and used to estimate nitrogen and phosphate flux. Sediment organic matter, carbonate, percent nitrogen, percent carbon, δ13C, and δ15N were measured from the reactor core stations. Oxygen was recorded continually using oxygen loggers while chlorophyll and salinity were measured bi-weekly. A hydrodynamic model was used to determine water renewal time at each station. The most severe eutrophication effects were in the upper one-fifth of the estuary. There were strong local relationships between sediment biogeochemistry, hypoxia, and chlorophyll metrics but not with water renewal time. Internal nutrient loading represented 65% and 69% of total N loading, and 98% and 89% of total P loading to the estuary in June and September, respectively. Sediment nitrogen flux was highly predictable from a range of local sediment variables that reflect either nutrient content, or organic carbon enrichment in general. Percent nitrogen and percent carbon were highly correlated but sediment P flux was poorly predicted from sediment parameters examined. The highest correlations were with percent nitrogen and percent carbon. These results indicate that incorporating internal nutrient loading into nutrient monitoring programs is a critical next step to improve predictive capacity for eutrophication endpoints and to mitigate nutrient effects.


Assuntos
Monitoramento Ambiental , Estuários , Humanos , Hipóxia , Oxigênio , Carbono , Clorofila , Nitrogênio , Nutrientes , Água
3.
Mar Environ Res ; 170: 105432, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34329883

RESUMO

While high levels of siltation are known to be deleterious to eastern oysters (Crassostrea virginica), the collective effect of suspended and bedded sediment is understudied from the perspective of oyster farming and bed restoration. In this study, we used laboratory experiments to explore spat settlement rates on a wild bed proxy substrate (i.e., empty shells on the bottom of experimental tanks) in conditions simulating a siltation event and the presence of suspended spat collectors. Using high-frequency valvometry, we also described the behavioural effects of acute sediment burial on wild adult oysters in situ. The vast majority of larvae settled on bottom substrate as opposed to suspended collectors. Sediment negatively affected overall oyster spat settlement on bottom shell, as spat densities were ≈3 × lower when sediment was present. This negative effect was largely attributed to severely depressed spat densities on the upper side (top) of bottom shells. Settlement on the underside of bottom shell was less affected. Wild adult oyster behaviour was negatively affected by acute burial, which ultimately resulted in death. We suggest that the reduction in settlement in the presence of siltation is likely due to the combined effects of suspended sediment on cue detection and bedded sediment on substrate availability. Given that oysters are ecosystem engineers, the negative effects of siltation on both larval and adult oysters can ultimately result in cascading effects to the surrounding biological community.


Assuntos
Crassostrea , Animais , Ecossistema , Larva
4.
Ultramicroscopy ; 231: 113264, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33902952

RESUMO

Inline electron holography, the recovery of amplitude and phase of an electron wave function having passed through a thin specimen from a focal series recorded in a transmission electron microscope is being applied in many labs worldwide. At medium range magnification (i.e. typically ≥0.8 nm where the lattice of small unit cell crystals such as silicon is not resolved), where the defocus needs to be varied over a rather large range of several hundred nm or even µm, the retrieval of low spatial frequency information is severely affected by the choice of experimental parameters as well as the way of data normalization. Methods to quantitatively analyze the reliability of phase maps obtained by inline electron holography are presented, and data recorded and processed in different ways are compared. While, even under optimized conditions, the phase reconstructed from an experimental focal series still lacks very low spatial frequency components, regularization schemes exist and are demonstrated to effectively hide artifacts associated with this lack of information.

5.
J Am Chem Soc ; 142(30): 12976-12986, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32597176

RESUMO

Covalent triazine frameworks are an emerging material class that have shown promising performance for a range of applications. In this work, we report on a metal-assisted and solvent-mediated reaction between calcium carbide and cyanuric chloride, as cheap and commercially available precursors, to synthesize two-dimensional triazine structures (2DTSs). The reaction between the solvent, dimethylformamide, and cyanuric chloride was promoted by calcium carbide and resulted in dimethylamino-s-triazine intermediates, which in turn undergo nucleophilic substitutions. This reaction was directed into two dimensions by calcium ions derived from calcium carbide and induced the formation of 2DTSs. The role of calcium ions to direct the two-dimensionality of the final structure was simulated using DFT and further proven by synthesizing molecular intermediates. The water content of the reaction medium was found to be a crucial factor that affected the structure of the products dramatically. While 2DTSs were obtained under anhydrous conditions, a mixture of graphitic material/2DTSs or only graphitic material (GM) was obtained in aqueous solutions. Due to the straightforward and gram-scale synthesis of 2DTSs, as well as their photothermal and photodynamic properties, they are promising materials for a wide range of future applications, including bacteria and virus incapacitation.

6.
Mar Pollut Bull ; 133: 261-270, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30041313

RESUMO

Simple empirical models can sometimes capture salient patterns without sacrificing predictive capacity when compared to more complex models. Herein we examine dissolved oxygen as an indicator of eutrophication status for shallow estuaries. Dissolved oxygen was measured hourly in the upper estuary of 15 watersheds along a nutrient-loading and geographic gradient. Metrics describing hypoxia and supersaturation were devised and then analyzed using multivariate statistics. Results revealed independent responses for hypoxia and supersaturation with hypoxia-related metrics correlating strongly with water residence. A metric integrating hypoxia and supersaturation effectively discriminated between seagrass and algae-dominated habitats and was significantly correlated with both water residence and nitrate-N loading. Chlorophyll, measured bi-weekly, was not correlated with our predictor variables likely because it does not account for benthic production. Over 70% of the variability in hypoxia was explained by water residence and nitrate-N loading indicating that this model can be of use for managers.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Eutrofização , Modelos Teóricos , Oxigênio/análise , Canadá , Clorofila/análise , Ecossistema
7.
Opt Express ; 26(9): 11819-11833, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29716099

RESUMO

The transport of intensity equation (TIE) relates the variation of intensity of a wave-front along its mean direction of propagation with its phase. In experimental application, characteristic artefacts may affect the retrieved phase. These originate from inadequacies in estimating the axial derivative and the amplification of noise in the inversion of the TIE. To tackle these issues, images recorded at multiple planes of focus can be integrated into a multi-focus TIE (MFTIE) solution. This methodology relies on the efficient sampling of phase information in the spatial-frequency domain, typically by the definition of band pass filters implemented as a progression of sharp spatial frequency cut-offs. We present a convenient MFTIE implementation which avoids the need for recording images at very specific planes of focus and applies overlapping cut-offs, greatly simplifying the experimental application. This new approach additionally also accounts for partial spatial coherence in a flux-preserving framework. Using simulated data as well as experimental data from optical microscopy and electron microscopy we show that the frequency response of this MFTIE algorithm recovers efficiently a wide range of spatial frequencies of the phase that can be further extended by simple iterative refinement.

8.
Europace ; 20(2): e1-e10, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339818

RESUMO

Aims: Cardiac resynchronization therapy (CRT) reduces morbidity and mortality in systolic heart failure patients with ventricular conduction delay. Variability of individual response to CRT warrants improved patient selection. The Markers and Response to CRT (MARC) study was designed to investigate markers related to response to CRT. Methods and results: We prospectively studied the ability of 11 clinical, 11 electrocardiographic, 4 echocardiographic, and 16 blood biomarkers to predict CRT response in 240 patients. Response was measured by the reduction of indexed left ventricular end-systolic volume (LVESVi) at 6 months follow-up. Biomarkers were related to LVESVi change using log-linear regression on continuous scale. Covariates that were significant univariately were included in a multivariable model. The final model was utilized to compose a response score. Age was 67 ± 10 years, 63% were male, 46% had ischaemic aetiology, LV ejection fraction was 26 ± 8%, LVESVi was 75 ± 31 mL/m2, and QRS was 178 ± 23 ms. At 6 months LVESVi was reduced to 58 ± 31 mL/m2 (relative reduction of 22 ± 24%), 130 patients (61%) showed ≥ 15% LVESVi reduction. In univariate analysis 17 parameters were significantly associated with LVESVi change. In the final model age, QRSAREA (using vectorcardiography) and two echocardiographic markers (interventricular mechanical delay and apical rocking) remained significantly associated with the amount of reverse ventricular remodelling. This CAVIAR (CRT-Age-Vectorcardiographic QRSAREA -Interventricular Mechanical delay-Apical Rocking) response score also predicted clinical outcome assessed by heart failure hospitalizations and all-cause mortality. Conclusions: The CAVIAR response score predicts the amount of reverse remodelling after CRT and may be used to improve patient selection. Clinical Trials: NCT01519908.

9.
Ultramicroscopy ; 184(Pt B): 98-105, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29102829

RESUMO

Electron energy-loss spectroscopy and energy-dispersive X-ray spectroscopy are two of the most common means for chemical analysis in the scanning transmission electron microscope. The marked progress of the instrumentation hardware has made chemical analysis at atomic resolution readily possible nowadays. However, the acquisition and interpretation of atomically resolved spectra can still be problematic due to image distortions and poor signal-to-noise ratio of the spectra, especially for investigation of energy-loss near-edge fine structures. By combining multi-frame spectrum imaging and automatic energy-offset correction, we developed a spectrum imaging technique implemented into customized DigitalMicrograph scripts for suppressing image distortions and improving the signal-to-noise ratio. With practical examples, i.e. SrTiO3 bulk material and Sr-doped La2CuO4 superlattices, we demonstrate the improvement of elemental mapping and the EELS spectrum quality, which opens up new possibilities for atomically resolved EELS fine structure mapping.

10.
Mar Pollut Bull ; 121(1-2): 339-351, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28633948

RESUMO

We analyzed surface sediments from 23 northeast USA estuaries, from Maine to Delaware, and nine estuaries from Prince Edward Island (PEI, Canada), to determine how dinoflagellate cyst assemblages varied with nutrient loading. Overall the abundance of cysts of heterotrophic dinoflagellates correlates with modeled nitrogen loading, but there were also regional signals. On PEI cysts of Gymnodinium microreticulatum characterized estuaries with high nitrogen loading while the sediments of eutrophic Boston Harbor were characterized by high abundances of Spiniferites spp. In Delaware Bay and the Delaware Inland Bays Polysphaeridium zoharyi correlated with higher temperatures and nutrient loading. This is the first study to document the dinoflagellate cyst eutrophication signal at such a large geographic scale in estuaries, thus confirming their value as indicators of water quality change and anthropogenic impact.


Assuntos
Dinoflagellida , Eutrofização , Animais , Canadá , Cistos , Delaware , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Maine , Nitrogênio , Fósforo , Ilha do Príncipe Eduardo , Poluentes da Água/análise
11.
PeerJ ; 5: e3080, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28348927

RESUMO

Eutrophic aquatic habitats are characterized by the proliferation of vegetation leading to a large standing biomass that upon decomposition may create hypoxic (low-oxygen) conditions. This is indeed the case in nutrient impacted estuaries of Prince Edward Island, Canada, where macroalgae, from the genus Ulva, form submerged ephemeral mats. Hydrological forces and gases released from photosynthesis and decomposition lead to these mats occasionally floating to the water's surface, henceforth termed floating mats. Here, we explore the hypothesis that floating mats are refugia during periods of sustained hypoxia/anoxia and examine how the invertebrate community responds to it. Floating mats were not always present, so in the first year (2013) sampling was attempted monthly and limited to when both floating and submerged mats occurred. In the subsequent year sampling was weekly, but at only one estuary due to logistical constraints from increased sampling frequency, and was not limited to when both mat types occurred. Water temperature, salinity, and pH were monitored bi-weekly with dissolved oxygen concentration measured hourly. The floating and submerged assemblages shared many of the same taxa but were statistically distinct communities; submerged mats tended to have a greater proportion of benthic animals and floating mats had more mobile invertebrates and insects. In 2014, sampling happened to occur in the weeks before the onset of anoxia, during 113 consecutive hours of sustained anoxia, and for four weeks after normoxic conditions returned. The invertebrate community on floating mats appeared to be unaffected by anoxia, indicating that these mats may be refugia during times of oxygen stress. Conversely, there was a dramatic decrease in animal abundances that remained depressed on submerged mats for two weeks. Cluster analysis revealed that the submerged mat communities from before the onset of anoxia and four weeks after anoxia were highly similar to each other, indicating recovery. When mobile animals were considered alone, there was an exponential relationship between the percentage of animals on floating mats, relative to the total number on both mat types, and hypoxia. The occupation of floating mats by invertebrates at all times, and their dominance there during hypoxia/anoxia, provides support for the hypothesis that floating mats are refugia.

12.
Ecol Evol ; 6(16): 5648-62, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27547344

RESUMO

Few biogeographic studies of dinoflagellate cysts include the near-shore estuarine environment. We determine the effect of estuary type, biogeography, and water quality on the spatial distribution of organic-walled dinoflagellate cysts from the Northeast USA (Maine to Delaware) and Canada (Prince Edward Island). A total of 69 surface sediment samples were collected from 27 estuaries, from sites with surface salinities >20. Dinoflagellate cysts were examined microscopically and compared to environmental parameters using multivariate ordination techniques. The spatial distribution of cyst taxa reflects biogeographic provinces established by other marine organisms, with Cape Cod separating the northern Acadian Province from the southern Virginian Province. Species such as Lingulodinium machaerophorum and Polysphaeridinium zoharyi were found almost exclusively in the Virginian Province, while others such as Dubridinium spp. and Islandinium? cezare were more abundant in the Acadian Province. Tidal range, sea surface temperature (SST), and sea surface salinity (SSS) are statistically significant parameters influencing cyst assemblages. Samples from the same type of estuary cluster together in canonical correspondence analysis when the estuaries are within the same biogeographic province. The large geographic extent of this study, encompassing four main estuary types (riverine, lagoon, coastal embayment, and fjord), allowed us to determine that the type of estuary has an important influence on cyst assemblages. Due to greater seasonal variations in SSTs and SSSs in estuaries compared to the open ocean, cyst assemblages show distinct latitudinal trends. The estuarine context is important for understanding present-day species distribution, the factors controlling them, and to better predict how they may change in the future.

13.
Adv Mater ; 27(33): 4845-50, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26178685

RESUMO

Semipolar {101¯1} InGaN quantum wells are grown on (001) Si substrates with an Al-free buffer and wafer-scale uniformity. The novel structure is achieved by a bottom-up nano-heteroepitaxy employing self-organized ZnO nanorods as the strain-relieving layer. This ZnO nanostructure unlocks the problems encountered by the conventional AlN-based buffer, which grows slowly and contaminates the growth chamber.


Assuntos
Gálio/química , Nanotecnologia/métodos , Nanotubos/química , Silício/química , Equipamentos e Provisões Elétricas , Nanotecnologia/instrumentação
14.
Dent Mater J ; 34(5): 572-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25948142

RESUMO

Among other factors, the precision of dental impressions is an important and determining factor for the fit of dental restorations. The aim of this study was to examine the three-dimensional (3D) precision of gypsum dies made using a range of impression techniques and materials. Ten impressions of a steel canine were fabricated for each of the 24 material-method-combinations and poured with type 4 die stone. The dies were optically digitized, aligned to the CAD model of the steel canine, and 3D differences were calculated. The results were statistically analyzed using one-way analysis of variance. Depending on material and impression technique, the mean values had a range between +10.9/-10.0 µm (SD 2.8/2.3) and +16.5/-23.5 µm (SD 11.8/18.8). Qualitative analysis using colorcoded graphs showed a characteristic location of deviations for different impression techniques. Three-dimensional analysis provided a comprehensive picture of the achievable precision. Processing aspects and impression technique were of significant influence.


Assuntos
Materiais para Moldagem Odontológica/química , Materiais para Moldagem Odontológica/classificação , Coloides/química , Éteres/química , Imageamento Tridimensional , Silicones/química
15.
J Therm Biol ; 43: 54-60, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24956958

RESUMO

The color-mediated thermoregulation hypothesis predicts that dark body color (low reflectance) allows organisms to gain heat more efficiently than does pale coloration (high reflectance). This prediction is intuitive and widely assumed to be true, but has poor empirical support. We used rare, captive-bred, mutant melanistic, albino and wild-type Australian bluetongue lizards, Tiliqua scincoides to measure the effects of skin reflectance on the heating and cooling rates. We measured heating under an artificial radiant heat source and cooling rates in an ice-cooled box using live lizards in a room with still air. The effect of skin reflectance on heat transfer was clear, despite the substantial influence of body size. Melanistic T. scincoides showed low reflectance and gained heat faster than highly reflective albinos. Melanistic lizards also lost heat faster than albinos. Wild-type lizards were intermediate in reflectance, gained heat at rates indistinguishable from melanistic lizards, and lost heat at rates indistinguishable from albino lizards. This study system allowed us to control for variables that were confounded in other studies and may explain the inconsistent support for the color-mediated thermoregulation hypothesis. Our results provide clear evidence that skin reflectance influences the rate of heating and cooling in ectotherms.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Lagartos/fisiologia , Pigmentação/fisiologia , Animais , Temperatura Corporal , Temperatura Baixa , Temperatura Alta
16.
Circ Heart Fail ; 7(2): 279-87, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24519908

RESUMO

BACKGROUND: Physical activity (PA) predicts cardiovascular mortality in the population at large. Less is known about its prognostic value in patients with chronic heart failure (HF). METHODS AND RESULTS: Data from 836 patients with implantable cardioverter defibrillator without or with cardiac resynchronization therapy enrolled in the Sensitivity of the InSync Sentry OptiVol feature for the prediction of Heart Failure (SENSE-HF)(1) study and the Diagnostic Outcome Trial in Heart Failure (DOT-HF) were pooled. The devices continuously measured and stored total daily active time (single-axis accelerometer). Early PA (average daily activity over the earliest 30-day study period) was studied as a predictor of time to death or HF-related hospital admission (primary end point). Data from 781 patients were analyzed (65±10 years; 85% men; left ventricular ejection fraction, 26±7%). Older age, shorter height, ischemic cause, peripheral artery disease, atrial fibrillation, diabetes mellitus, rales, peripheral edema, higher New York Heart Association class, lower diastolic blood pressure, and no angiotensin II receptor blocker/angiotensin-converting enzyme inhibitor use were associated with reduced early PA. The primary end point occurred in 135 patients (15±7 months of follow-up). In multivariable analysis including baseline variables, early PA predicted death or HF hospitalization, with a 4% reduction in risk for each 10 minutes per day additional activity (hazard ratio [HR], 0.96; confidence interval [CI], 0.94-0.98; P=0.0002 compared with a model with the same baseline variables but without PA). PA also predicted death (HR, 0.93; CI, 0.90-0.96; P<0.0001) and HF hospitalization (HR, 0.97; CI, 0.95-0.99; P=0.011). CONCLUSIONS: Early PA, averaged over a 30-day window early after defibrillator implantation or cardiac resynchronization therapy in patients with chronic HF, predicted death or HF hospitalization, as well as mortality and HF hospitalization separately, accounting for baseline HF severity. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00400985, NCT00480077.


Assuntos
Desfibriladores Implantáveis , Insuficiência Cardíaca/fisiopatologia , Atividade Motora/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Feminino , Seguimentos , Saúde Global , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Prognóstico , Estudos Retrospectivos , Volume Sistólico , Taxa de Sobrevida , Fatores de Tempo
17.
Nanotechnology ; 24(4): 045601, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23291468

RESUMO

Well-controlled growth of Ag nanoparticles (NPs) on Si substrates is important for next generation Si-based optoelectronic devices, but only randomly oriented Ag NPs have been previously reported. In this work, well-oriented Ag NPs with regular shapes are pseudomorphically grown on Si(100) and Si(111) substrates with crystallographic relationships of {100} mathematical left angle bracket 010 mathematical right angle bracket Ag ∥ {100} mathematical left angle bracket 010 mathematical right angle bracket Si and {111} mathematical left angle bracket 110 mathematical right angle bracket Ag ∥ {111} mathematical left angle bracket 110 mathematical right angle bracket Si, respectively. From a cross-sectional image, the Ag NPs on Si(100) substrates penetrate into Si and generate an inverted pyramid-like structure terminated by {111} planes embedded in Si substrates. In contrast, the Ag NPs on Si(111) substrates show flat morphology with the top plane terminated by Ag {111}. The Si underneath Ag NPs was not penetrated by Ag and a SiO(2) layer was formed between Ag and Si. Photoluminescence spectra of the Ag NPs show ultraviolet emissions centered in the 340-343 nm range. The mathematical left angle bracket 111 mathematical right angle bracket-oriented Ag particles show stronger emissions with an extra peak at 343 nm compared with mathematical left angle bracket 100 mathematical right angle bracket-oriented Ag NPs. Raman spectra show that the mathematical left angle bracket 100 mathematical right angle bracket - and mathematical left angle bracket 111 mathematical right angle bracket-oriented Ag NPs can enhance the peak intensity of Si(100) and Si(111) by 45.3% and 32.5%, respectively. The orientation-controlled Ag NPs with anisotropic optical properties are promising materials for Si-based optoelectronics.


Assuntos
Cristalização/métodos , Nanopartículas Metálicas/química , Silício/química , Prata/química , Adsorção , Luz , Teste de Materiais , Nanopartículas Metálicas/efeitos da radiação , Conformação Molecular/efeitos da radiação , Tamanho da Partícula , Refratometria , Espalhamento de Radiação , Prata/efeitos da radiação , Propriedades de Superfície/efeitos da radiação
18.
Atherosclerosis ; 219(1): 200-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21726863

RESUMO

AIM: Inflammation is a risk factor for coronary heart disease (CHD). A common deletion-allele in the promoter region of NFKB1 results in lower protein levels of the NF-κB p50 subunit. Recent evidence suggests that the NF-κB p50 dimer has anti-inflammatory effects. We aimed to investigate the association of the functional ATTG NFKB1 insertion/deletion variant with risk of CHD in three independent prospective studies of generally healthy men and women. METHODS AND RESULTS: The NFKB1 ins/del polymorphism was genotyped in studies of CHD nested within the Diet, Cancer and Health (DCH) study, the Health Professionals Follow-up (HPFS) and the Nurses' Health (NHS) studies, totaling 1008, 428 and 439 cases, respectively. The minor allele frequency in the combined sample was 0.38 among controls. In a pooled analysis, the relative risk (RR) among heterozygous men and women was 1.22 (95% CI: 1.07-1.40), compared to the most common ins/ins genotype. The RR among homozygotes was 1.20 (95% CI: 0.94-1.53). There was no evidence of an allele-dosage effect, and in a dominant model the RR among del-allele carriers was 1.22 (95% CI: 1.07-1.39). The risk was similar in women and men (RR was 1.20 in women and 1.23 in men, respectively). The NFKB1 variant was not associated with plasma lipid levels, but del-carriers had lower levels of C-reactive protein. CONCLUSIONS: The NFKB1 promoter variant, previously shown to cause partial depletion of NF-κB p50, was associated with a higher risk of CHD in three independent prospective studies of generally healthy Caucasians.


Assuntos
Doença das Coronárias/genética , Mutação INDEL , Subunidade p50 de NF-kappa B/genética , Deleção de Sequência , Adulto , Idoso , Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Dinamarca/epidemiologia , Feminino , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Estudos Prospectivos , Risco , Estados Unidos/epidemiologia
19.
J Natl Cancer Inst ; 102(8): 529-37, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20371762

RESUMO

BACKGROUND: It is widely believed that cancer can be prevented by high intake of fruits and vegetables. However, inconsistent results from many studies have not been able to conclusively establish an inverse association between fruit and vegetable intake and overall cancer risk. METHODS: We conducted a prospective analysis of the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to assess relationships between intake of total fruits, total vegetables, and total fruits and vegetables combined and cancer risk during 1992-2000. Detailed information on the dietary habit and lifestyle variables of the cohort was obtained. Cancer incidence and mortality data were ascertained, and hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using multivariable Cox regression models. Analyses were also conducted for cancers associated with tobacco and alcohol after stratification for tobacco smoking and alcohol drinking. RESULTS: Of the initial 142 605 men and 335 873 women included in the study, 9604 men and 21 000 women were identified with cancer after a median follow-up of 8.7 years. The crude cancer incidence rates were 7.9 per 1000 person-years in men and 7.1 per 1000 person-years in women. Associations between reduced cancer risk and increased intake of total fruits and vegetables combined and total vegetables for the entire cohort were similar (200 g/d increased intake of fruits and vegetables combined, HR = 0.97, 95% CI = 0.96 to 0.99; 100 g/d increased intake of total vegetables, HR = 0.98, 95% CI = 0.97 to 0.99); intake of fruits showed a weaker inverse association (100 g/d increased intake of total fruits, HR = 0.99, 95% CI = 0.98 to 1.00). The reduced risk of cancer associated with high vegetable intake was restricted to women (HR = 0.98, 95% CI = 0.97 to 0.99). Stratification by alcohol intake suggested a stronger reduction in risk in heavy drinkers and was confined to cancers caused by smoking and alcohol. CONCLUSIONS: A very small inverse association between intake of total fruits and vegetables and cancer risk was observed in this study. Given the small magnitude of the observed associations, caution should be applied in their interpretation.


Assuntos
Comportamento Alimentar , Frutas , Neoplasias/epidemiologia , Neoplasias/prevenção & controle , Verduras , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Variações Dependentes do Observador , Razão de Chances , Estudos Prospectivos , Sistema de Registros , Projetos de Pesquisa , Medição de Risco , Fatores de Risco , Inquéritos e Questionários
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA