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1.
Sci Adv ; 9(45): eadi9135, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37948521

RESUMO

The extent of vegetation openness in past European landscapes is widely debated. In particular, the temperate forest biome has traditionally been defined as dense, closed-canopy forest; however, some argue that large herbivores maintained greater openness or even wood-pasture conditions. Here, we address this question for the Last Interglacial period (129,000-116,000 years ago), before Homo sapiens-linked megafauna declines and anthropogenic landscape transformation. We applied the vegetation reconstruction method REVEALS to 96 Last Interglacial pollen records. We found that light woodland and open vegetation represented, on average, more than 50% cover during this period. The degree of openness was highly variable and only partially linked to climatic factors, indicating the importance of natural disturbance regimes. Our results show that the temperate forest biome was historically heterogeneous rather than uniformly dense, which is consistent with the dependency of much of contemporary European biodiversity on open vegetation and light woodland.


Assuntos
Ecossistema , Florestas , Humanos , Biodiversidade , Pólen , Madeira , Árvores
2.
J Laryngol Otol ; 136(2): 176-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34649636

RESUMO

BACKGROUND: Cochlear implantation can be used when a patient's hearing cannot satisfactorily be improved after optimised hearing aid fitting. However, in patients with a cochlear nerve or brain disorder affecting hearing, the benefits of cochlear implants are not so straightforward. METHODS: This paper describes a 58-year-old patient suffering from multiple sclerosis and profound sensorineural hearing loss, rehabilitated with a cochlear implant. Literature concerning cochlear implantation in demyelinating conditions was systematically reviewed using PubMed/Medline and Web of Science databases. RESULTS: The patient's cochlear implantation was successful, with speech discrimination scores remaining above 90 per cent for eight years post-operatively. No previous cases of cochlear implantation with multiple sclerosis related hearing loss have been reported, despite the high incidence of hearing loss in multiple sclerosis patients. CONCLUSION: This paper demonstrates that multiple sclerosis lesions should not be an exclusion criterion in an otherwise suitable candidate for cochlear implantation.


Assuntos
Implante Coclear , Perda Auditiva Neurossensorial/reabilitação , Esclerose Múltipla/fisiopatologia , Perda Auditiva Neurossensorial/complicações , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Índice de Gravidade de Doença , Resultado do Tratamento
3.
Sci Adv ; 7(31)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34330702

RESUMO

The effects of climate change on species richness are debated but can be informed by the past. Here, we generated a sedimentary ancient DNA dataset covering 10 lakes and applied novel methods for data harmonization. We assessed the impact of Holocene climate changes and nutrients on terrestrial plant richness in northern Fennoscandia. We find that richness increased steeply during the rapidly warming Early Holocene. In contrast to findings from most pollen studies, we show that richness continued to increase thereafter, although the climate was stable, with richness and the regional species pool only stabilizing during the past three millennia. Furthermore, overall increases in richness were greater in catchments with higher soil nutrient availability. We suggest that richness will increase with ongoing warming, especially at localities with high nutrient availability and assuming that human activity remains low in the region, although lags of millennia may be expected.


Assuntos
DNA Antigo , Plantas , Mudança Climática , Ecossistema , Humanos , Lagos , Plantas/genética , Pólen
4.
Sci Rep ; 11(1): 7, 2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33414490

RESUMO

Dogs (Canis familiaris) are the first animals to be domesticated by humans and the only ones domesticated by mobile hunter-gatherers. Wolves and humans were both persistent, pack hunters of large prey. They were species competing over resources in partially overlapping ecological niches and capable of killing each other. How could humans possibly have domesticated a competitive species? Here we present a new hypothesis based on food/resource partitioning between humans and incipient domesticated wolves/dogs. Humans are not fully adapted to a carnivorous diet; human consumption of meat is limited by the liver's capacity to metabolize protein. Contrary to humans, wolves can thrive on lean meat for months. We present here data showing that all the Pleistocene archeological sites with dog or incipient dog remains are from areas that were analogous to subarctic and arctic environments. Our calculations show that during harsh winters, when game is lean and devoid of fat, Late Pleistocene hunters-gatherers in Eurasia would have a surplus of animal derived protein that could have been shared with incipient dogs. Our partitioning theory explains how competition may have been ameliorated during the initial phase of dog domestication. Following this initial period, incipient dogs would have become docile, being utilized in a multitude of ways such as hunting companions, beasts of burden and guards as well as going through many similar evolutionary changes as humans.


Assuntos
Evolução Biológica , Cães , Domesticação , Animais , Animais Domésticos , Regiões Árticas , Restos Mortais , Humanos , Camada de Gelo , Proteínas , Estações do Ano , Lobos
5.
Sci Rep ; 9(1): 15805, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31676769

RESUMO

We test several quantitative algorithms as palaeoclimate reconstruction tools for North American and European fossil pollen data, using both classical methods and newer machine-learning approaches based on regression tree ensembles and artificial neural networks. We focus on the reconstruction of secondary climate variables (here, January temperature and annual water balance), as their comparatively small ecological influence compared to the primary variable (July temperature) presents special challenges to palaeo-reconstructions. We test the pollen-climate models using a novel and comprehensive cross-validation approach, running a series of h-block cross-validations using h values of 100-1500 km. Our study illustrates major benefits of this variable h-block cross-validation scheme, as the effect of spatial autocorrelation is minimized, while the cross-validations with increasing h values can reveal instabilities in the calibration model and approximate challenges faced in palaeo-reconstructions with poor modern analogues. We achieve well-performing calibration models for both primary and secondary climate variables, with boosted regression trees providing the overall most robust performance, while the palaeoclimate reconstructions from fossil datasets show major independent features for the primary and secondary variables. Our results suggest that with careful variable selection and consideration of ecological processes, robust reconstruction of both primary and secondary climate variables is possible.

6.
Nat Commun ; 9(1): 2851, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-30030443

RESUMO

The Eemian (the Last Interglacial; ca. 129-116 thousand years ago) presents a testbed for assessing environmental responses and climate feedbacks under warmer-than-present boundary conditions. However, climate syntheses for the Eemian remain hampered by lack of data from the high-latitude land areas, masking the climate response and feedbacks in the Arctic. Here we present a high-resolution (sub-centennial) record of Eemian palaeoclimate from northern Finland, with multi-model reconstructions for July and January air temperature. In contrast with the mid-latitudes of Europe, our data show decoupled seasonal trends with falling July and rising January temperatures over the Eemian, due to orbital and oceanic forcings. This leads to an oceanic Late-Eemian climate, consistent with an earlier hypothesis of glacial inception in Europe. The interglacial is further intersected by two strong cooling and drying events. These abrupt events parallel shifts in marine proxy data, linked to disturbances in the North Atlantic oceanic circulation regime.

7.
J Mater Chem B ; 4(11): 2051-2058, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263082

RESUMO

In this study, the antibacterial efficacy of NO-releasing porous silicon nanoparticles (pSiNPs) is reported. NO-releasing pSiNPs were produced via the conjugation of S-nitrosothiol (SNO) and S-nitrosoglutathione (GSNO) donors to the nanoparticle surfaces. The release of the conjugated NO caused by the decomposition of the conjugated SNO and GSNO was boosted in the presence of ascorbic acid. The released NO was bactericidal to Gram-positive (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli), and eliminated bacterial growth within 2 h of incubation without compromising the viability of mammalian cells. These results demonstrate the advantages of NO-releasing pSiNPs for antibacterial applications, for example, in chronic wound treatment.

8.
Biomater Sci ; 3(12): 1555-65, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26343506

RESUMO

In this study, thermally hydrocarbonised porous silicon nanoparticles (THCpSiNPs) capped with polyethylenimine (PEI) were fabricated, and their potential for small interfering RNA (siRNA) delivery was investigated in an in vitro glioblastoma model. PEI coating following siRNA loading enhanced the sustained release of siRNA, and suppressed burst release effects. The positively-charged surface improved the internalisation of the nanoparticles across the cell membrane. THCpSiNP-mediated siRNA delivery reduced mRNA expression of the MRP1 gene, linked to the resistence of glioblastoma to chemotherapy, by 63% and reduced MRP1-protein levels by 70%. MRP1 siRNA loaded nanoparticles did not induce cytotoxicity in glioblastoma cells, but markedly reduced cell proliferation. In summary, the results demonstrated that non-cytotoxic cationic THCpSiNPs are promising vehicles for therapeutic siRNA delivery.


Assuntos
Glioblastoma/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Nanopartículas/administração & dosagem , Polietilenoimina/química , RNA Interferente Pequeno/administração & dosagem , Silício/química , Linhagem Celular Tumoral , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Nanopartículas/química , Polietilenoimina/metabolismo , Porosidade , RNA Interferente Pequeno/química
9.
Nat Commun ; 6: 6809, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25858780

RESUMO

Holocene summer temperature reconstructions from northern Europe based on sedimentary pollen records suggest an onset of peak summer warmth around 9,000 years ago. However, pollen-based temperature reconstructions are largely driven by changes in the proportions of tree taxa, and thus the early-Holocene warming signal may be delayed due to the geographical disequilibrium between climate and tree populations. Here we show that quantitative summer-temperature estimates in northern Europe based on macrofossils of aquatic plants are in many cases ca. 2 °C warmer in the early Holocene (11,700-7,500 years ago) than reconstructions based on pollen data. When the lag in potential tree establishment becomes imperceptible in the mid-Holocene (7,500 years ago), the reconstructed temperatures converge at all study sites. We demonstrate that aquatic plant macrofossil records can provide additional and informative insights into early-Holocene temperature evolution in northernmost Europe and suggest further validation of early post-glacial climate development based on multi-proxy data syntheses.


Assuntos
Organismos Aquáticos/fisiologia , Fósseis , Modelos Estatísticos , Pólen/fisiologia , Árvores/fisiologia , Clima , Simulação por Computador , Europa (Continente) , Dispersão Vegetal/fisiologia , Estações do Ano , Temperatura
10.
Clin Microbiol Infect ; 21(1): 87.e1-87.e10, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25636940

RESUMO

A prospective, observational, multicentre study of invasive candidosis (IC) in surgical patients in intensive care units (ICUs) was conducted from 2006 to 2008 in 72 ICUs in 14 European countries. A total of 779 patients (62.5% males, median age 63 years) with IC were included. The median rate of candidaemia was 9 per 1000 admissions. In 10.8% the infection was already present at the time of admission to ICU. Candida albicans accounted for 54% of the isolates, followed by Candida parapsilosis 18.5%, Candida glabrata 13.8%, Candida tropicalis 6%, Candida krusei 2.5%, and other species 5.3%. Infections due to C. krusei (57.9%) and C. glabrata (43.6%) had the highest crude mortality rate. The most common preceding surgery was abdominal (51.5%), followed by thoracic (20%) and neurosurgery (8.2%). Candida glabrata was more often isolated after abdominal surgery in patients ≥60 years, and C. parapsilosis was more often isolated in neurosurgery and multiple trauma patients as well as children ≤1 year of age. The most common first-line treatment was fluconazole (60%), followed by caspofungin (18.7%), liposomal amphotericin B (13%), voriconazole (4.8%) and other drugs (3.5%). Mortality in surgical patients with IC in ICU was 38.8%. Multivariate analysis showed that factors independently associated with mortality were: patient age ≥60 years (hazard ratio (HR) 1.9, p 0.001), central venous catheter (HR 1.8, p 0.05), corticosteroids (HR 1.5, p 0.03), not receiving systemic antifungal treatment for IC (HR 2.8, p <0.0001), and not removing intravascular lines (HR 1.6, p 0.02).


Assuntos
Candida , Candidíase Invasiva/epidemiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibioticoprofilaxia , Antifúngicos/uso terapêutico , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/prevenção & controle , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
11.
Philos Trans R Soc Lond B Biol Sci ; 370(1660): 20130382, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25487333

RESUMO

We compared DNA, pollen and macrofossil data obtained from Weichselian interstadial (age more than 40 kyr) and Holocene (maximum age 8400 cal yr BP) peat sediments from northern Europe and used them to reconstruct contemporary floristic compositions at two sites. The majority of the samples provided plant DNA sequences of good quality with success amplification rates depending on age. DNA and sequencing analysis provided five plant taxa from the older site and nine taxa from the younger site, corresponding to 7% and 15% of the total number of taxa identified by the three proxies together. At both sites, pollen analysis detected the largest (54) and DNA the lowest (10) number of taxa, but five of the DNA taxa were not detected by pollen and macrofossils. The finding of a larger overlap between DNA and pollen than between DNA and macrofossils proxies seems to go against our previous suggestion based on lacustrine sediments that DNA originates principally from plant tissues and less from pollen. At both sites, we also detected Quercus spp. DNA, but few pollen grains were found in the record, and these are normally interpreted as long-distance dispersal. We confirm that in palaeoecological investigations, sedimentary DNA analysis is less comprehensive than classical morphological analysis, but is a complementary and important tool to obtain a more complete picture of past flora.


Assuntos
DNA de Plantas/genética , Fósseis , Sedimentos Geológicos/química , Pólen/genética , Solo/química , Sequência de Bases , DNA de Plantas/classificação , DNA de Plantas/história , Finlândia , História Antiga , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Multiplex , Federação Russa , Análise de Sequência de DNA/métodos
12.
B-ENT ; 9(1): 23-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23641587

RESUMO

OBJECTIVES: A decreasing but still substantial proportion of elderly persons with hearing aids use them only occasionally. Because the prevalence of age-related hearing loss is increasing, it is important for the hearing rehabilitation process to be effective. The aim of this study was to use a mailed questionnaire to evaluate the rate of hearing aid use and the reasons for minimal use or nonuse. METHODS: Questions about hearing aid use and associated problems were included in a survey of hearing mailed to 4,067 people in age cohorts of 70, 75, 80 and 85 years in an industrialized urban community in Finland. RESULTS: In this sample of 249 hearing aid users, 55.4% used their hearing aid daily, and 27.3% used it > 6 hours a day. The percentage of subjects who never used their hearing aid was 10.7%. Use of hearing aids tended to decline with advancing age. The most common reasons for minimal use were disturbing background noise, acoustic feedback problems, battery cost, and a lack of motivation to use the hearing aid. CONCLUSIONS: Compliance with hearing aid use by the elderly is increasing, but a significant proportion of hearing aids are still used only occasionally or never. We discuss methods to improve compliance in this patient group. Our results may be used to reexamine existing procedures for fitting hearing aids for counseling, which may increase patient compliance with hearing aids, leading to greater benefits from their use.


Assuntos
Auxiliares de Audição/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Presbiacusia/reabilitação , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Finlândia , Auxiliares de Audição/economia , Auxiliares de Audição/psicologia , Humanos , Masculino , Motivação , Ruído , Cooperação do Paciente/psicologia , Inquéritos e Questionários , População Urbana
13.
Diabetologia ; 56(7): 1494-502, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23568273

RESUMO

AIMS/HYPOTHESIS: The aim of this work was to investigate whether measurement of the mean common carotid intima-media thickness (CIMT) improves cardiovascular risk prediction in individuals with diabetes. METHODS: We performed a subanalysis among 4,220 individuals with diabetes in a large ongoing individual participant data meta-analysis involving 56,194 subjects from 17 population-based cohorts worldwide. We first refitted the risk factors of the Framingham heart risk score on the individuals without previous cardiovascular disease (baseline model) and then expanded this model with the mean common CIMT (CIMT model). The absolute 10 year risk for developing a myocardial infarction or stroke was estimated from both models. In individuals with diabetes we compared discrimination and calibration of the two models. Reclassification of individuals with diabetes was based on allocation to another cardiovascular risk category when mean common CIMT was added. RESULTS: During a median follow-up of 8.7 years, 684 first-time cardiovascular events occurred among the population with diabetes. The C statistic was 0.67 for the Framingham model and 0.68 for the CIMT model. The absolute 10 year risk for developing a myocardial infarction or stroke was 16% in both models. There was no net reclassification improvement with the addition of mean common CIMT (1.7%; 95% CI -1.8, 3.8). There were no differences in the results between men and women. CONCLUSIONS/INTERPRETATION: There is no improvement in risk prediction in individuals with diabetes when measurement of the mean common CIMT is added to the Framingham risk score. Therefore, this measurement is not recommended for improving individual cardiovascular risk stratification in individuals with diabetes.


Assuntos
Doenças Cardiovasculares/epidemiologia , Espessura Intima-Media Carotídea , Diabetes Mellitus/epidemiologia , Humanos , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
14.
J Vet Pharmacol Ther ; 34(1): 76-81, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21219348

RESUMO

The objective of the study was to determine the absorption, bioavailability and sedative effect of detomidine administered to horses as an oromucosal gel compared to intravenous and intramuscular administration of detomidine injectable solution. The study was open and randomized, with three sequences crossover design. Nine healthy horses were given 40 µg/kg detomidine intravenously, intramuscularly or administered under the tongue with a 7-day wash-out period between treatments. Blood samples were collected before and after drug administration for the measurement of detomidine concentrations in serum. The effects of the route of administration on heart rate and rhythm were evaluated and the depth of sedation assessed. Mean (±SD) bioavailability of detomidine was 22% (±5.3%) after sublingual administration and 38.2% (±7.9%) after intramuscular administration. The sedative effects correlated with detomidine concentrations regardless of the route of administration. We conclude that less detomidine is absorbed when given sublingually than when given intramuscularly, because part of it does not reach the circulation. Sublingual administration of detomidine oromucosal gel at 40 µg/kg produces safe sedation in horses. Slow absorption leads to fewer and less pronounced adverse effects than the more rapid absorption after intramuscular injection.


Assuntos
Disponibilidade Biológica , Géis , Cavalos/sangue , Hipnóticos e Sedativos/farmacocinética , Imidazóis/farmacocinética , Administração Sublingual , Animais , Estudos Cross-Over , Vias de Administração de Medicamentos , Feminino , Hipnóticos e Sedativos/sangue , Imidazóis/sangue , Masculino
16.
Med Mycol ; 48(3): 458-65, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19672782

RESUMO

Deep, respiratory tract and ear infections due to Microascaceae (Pseudallescheria, Scedosporium, Microascus or Scopulariopsis) were studied nationwide in Finland during 1993-2002. The data were based on 52,000 fungal cultures that represented about 50% of all such specimens in Finland and included all Finnish cases of profound immunosuppression. There were 39 cases that were re-evaluated as clinically significant, i.e., three pneumonias, two deep pedal infections and five wound infections, 11 sinusitis and 18 ear infections. The pedal infections and most pneumonias occurred in immunocompromised patients. Most cases, except the ear infections, were due to Pseudallescheria boydii. Two patients had lethal P. boydii pneumonia and a deep P. boydii infection of the foot contributed to a third lethal case. Two of the patients with lethal outcomes had received an allogeneic haematopoietic stem cell transplantation (AHSCT). Two patients with haematological malignancies were cured of deep site infections by a prolonged course of itraconazole. Wound, sinus and ear infections were cured or improved by local surgery or topical therapy. There were 0.8-1.7 cases of any type of infection per million inhabitants per year (MY) and 3.4 cases/1000 AHSCT. Mortality associated with Microascaceae in any type of patient was 0.06-0.12 MY.


Assuntos
Ascomicetos/isolamento & purificação , Micoses/epidemiologia , Micoses/microbiologia , Otite/epidemiologia , Otite/microbiologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/administração & dosagem , Criança , Desbridamento , Feminino , Finlândia/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Pessoa de Meia-Idade , Micoses/mortalidade , Micoses/terapia , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
17.
J Control Release ; 137(2): 166-70, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19345247

RESUMO

Peptides may represent potential treatment options for many severe illnesses. However, they need an effective delivery system to overcome rapid degradation after their administration. One possible way to prolong peptide action is to use particulate drug delivery systems. In the present study, thermally hydrocarbonized mesoporous silicon (THCPSi) microparticles (38-53 microm) were studied as a peptide delivery system in vivo. D-lys-GHRP6 (ghrelin antagonist, GhA) was used as a model peptide. The effects of GhA-loaded THCPSi microparticles on food intake (s.c., GhA dose 14 mg/kg) and on blood pressure (s.c., GhA dose 4 mg/kg) were examined in mice and rats, respectively. In addition, the effects of THCPSi microparticles (2 mg) on cytokine secretion in mice after single s.c. administration were examined by determining several cytokine plasma concentrations. The present results demonstrate that GhA can be loaded into THCPSi microparticles with a high loading degree (20% w/w). GhA loaded THCPSi microparticles inhibited food intake for a prolonged time, and increased blood pressure more slowly than encountered with a GhA solution. Furthermore, THCPSi microparticles did not increase cytokine activity. The present results suggest that THCPSi might be used as a drug delivery system for peptides.


Assuntos
Grelina/antagonistas & inibidores , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Silício/química , Animais , Pressão Sanguínea/efeitos dos fármacos , Citocinas/sangue , Citocinas/imunologia , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Ratos , Ratos Wistar , Silício/administração & dosagem , Silício/imunologia , Silício/farmacologia , Fatores de Tempo
18.
Heart ; 95(13): 1067-71, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19321489

RESUMO

BACKGROUND: Risk stratification for cardiovascular outcomes is gaining importance in general population. Prognostic value of natriuretic peptides has been established in patients with heart failure. However, the prognostic significance of natriuretic peptides with respect to stroke is not well known in general populations. METHODS: Plasma natriuretic peptides were measured in a representative population-based sample of 958 men (age 46-65 years) from Eastern Finland. There were 46 cases of stroke, 74 of atrial fibrillation and 31 cases of ischaemic strokes during a follow-up of 9.6 years. RESULTS: The multivariable adjusted risk was 1.35-fold (95% CI 1.01 to 1.84, p = 0.049) for any stroke and 1.30-fold (95% CI 0.90 to 1.91, p = 0.0150) for ischaemic stroke for each log-transformed SD (0.240 pmol/l) increment in N-terminal fragment of proA-type natriuretic peptide. The respective risks were 1.36-fold (95% CI 1.05 to 1.76, p = 0.010) and 1.50-fold (95% CI 1.12 to 2.02, p = 0.007) for each log-transformed SD (0.237 pmol/l) increment in N-terminal fragment of proB-type natriuretic peptide. The multivariate adjusted risks for future atrial fibrillation were 1.71 (95% CI 1.32 to 2.22, p<0.001) and 1.68-fold (95% CI 1.38 to 2.07, p<0.001) for each log-transformed SD increment in N-terminal fragments of proA- and proB-type natriuretic peptides, respectively. CONCLUSIONS: N-terminal fragments of pro-atrial natriuretic peptide and pro-brain natriuretic peptide are new additional predictors of any stroke and atrial fibrillation. Natriuretic peptides provide prognostic information for stroke and atrial fibrillation and may help in identifying subjects at risk for stroke and atrial fibrillation.


Assuntos
Fibrilação Atrial/diagnóstico , Peptídeos Natriuréticos/sangue , Acidente Vascular Cerebral/diagnóstico , Idoso , Fibrilação Atrial/sangue , Fator Natriurético Atrial/sangue , Biomarcadores/sangue , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Prognóstico , Precursores de Proteínas/sangue , Medição de Risco/métodos , Acidente Vascular Cerebral/sangue
19.
Stat Med ; 28(8): 1218-37, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19222087

RESUMO

One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154,012 participants in 31 cohorts


Assuntos
Estudos de Coortes , Interpretação Estatística de Dados , Metanálise como Assunto , Modelos Estatísticos , Simulação por Computador , Doença das Coronárias/metabolismo , Feminino , Fibrinogênio/análise , Humanos , Masculino
20.
Eur J Clin Nutr ; 63(5): 684-91, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18270526

RESUMO

BACKGROUND/OBJECTIVES: To assess safety during a diet based on low-fat foods enriched with nonesterified wood-derived plant sterols and mineral nutrients related to serum phytosterol, sex hormone and fat-soluble vitamin metabolism. SUBJECTS/METHODS: Seventy-one study participants (52 women, 19 men) with mild-to-moderate hypercholesterolemia completed the double-blind, placebo-controlled feeding trial lasting for 15 weeks. The subjects were randomly allocated to the sterol group receiving food items enriched with mineral nutrients as well as with a total of 1.25, 2.5 and 5.0 g per day of plant sterols during the first, second and third 5-week periods, respectively, or to the placebo group receiving similar food items without plant sterols. This outpatient clinical trial with free-living subjects was carried out at two hospital clinics. RESULTS: Two significant findings were observed. Serum sitosterol concentrations increased from 2.84 to 5.35 mg l(-1) (P<0.004 vs placebo) but those of serum total plant sterols did not because of compensatory changes in other phytosterols. The highest plant sterol levels did not exceed 0.6% of total serum sterols. Serum alpha-tocopherol concentrations decreased in the sterol group by 10% (P<0.0002), but the between-group difference disappeared after adjusting for the change in the carrier (LDL cholesterol). CONCLUSIONS: Fifteen-week consumption of natural nonesterified plant sterol-enriched food does not cause any serious adverse effects during such a period. However, serum alpha-tocopherol levels were somewhat reduced in the sterol group suggesting that long-term effects of plant sterols on serum fat-soluble vitamin concentrations should be further explored, especially in relation to very low-fat diets.


Assuntos
Alimentos Fortificados , Hipolipemiantes/sangue , Fitosteróis/efeitos adversos , Sitosteroides/sangue , Adulto , Idoso , LDL-Colesterol/sangue , Dieta , Método Duplo-Cego , Feminino , Finlândia , Hormônios Esteroides Gonadais/sangue , Humanos , Hipercolesterolemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fitosteróis/sangue , Fitosteróis/uso terapêutico , Vitaminas/sangue , alfa-Tocoferol/sangue
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