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1.
J Trace Elem Med Biol ; 84: 127462, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38701651

RESUMO

Aging is associated with a decline in physiological functions and an increased risk of age-related diseases, emphasizing the importance of identifying dietary strategies for healthy aging. Minerals play a crucial role in maintaining optimal health during aging, making them relevant targets for investigation. Therefore, we aimed to analyze the effect of different dietary pattern on mineral status in the elderly. We included 502 individuals aged 50-80 years in a 36-month randomized controlled trial (RCT) (NutriAct study). This article focuses on the results within the two-year intervention period. NutriAct is not a mineral-modulating-targeted intervention study, rather examining nutrition in the context of healthy aging in general. However, mineral status might be affected in an incidental manner. Participants were assigned to either NutriAct dietary pattern (proportionate intake of total energy consumption (%E) of 35-45 %E carbohydrates, 35-40 %E fats, and 15-25 %E protein) or the German Nutrition Society (DGE) dietary pattern (proportionate intake of total energy consumption (%E) of 55 %E carbohydrates, 30 %E fats, and 15 %E protein), differing in the composition of macronutrients. Data from 368 participants regarding dietary intake (energy, calcium, magnesium, iron, and zinc) and serum mineral concentrations of calcium, magnesium, iron, copper, zinc, selenium, iodine, and manganese, free zinc, and selenoprotein P were analyzed at baseline, as well as after 12 and 24 months to gain comprehensive insight into the characteristics of the mineral status. Additionally, inflammatory status - sensitive to changes in mineral status - was assessed by measurement of C-reactive protein and interleukin-6. At baseline, inadequate dietary mineral intake and low serum concentrations of zinc and selenium were observed in both dietary patterns. Throughout two years, serum zinc concentrations decreased, while an increase of serum selenium, manganese and magnesium concentrations was observable, likely influenced by both dietary interventions. No significant changes were observed for serum calcium, iron, copper, or iodine concentrations. In conclusion, long-term dietary interventions can influence serum mineral concentrations in a middle-aged population. Our findings provide valuable insights into the associations between dietary habits, mineral status, and disease, contributing to dietary strategies for healthy aging.


Assuntos
Envelhecimento Saudável , Minerais , Humanos , Pessoa de Meia-Idade , Idoso , Masculino , Feminino , Alemanha , Envelhecimento Saudável/sangue , Idoso de 80 Anos ou mais , Minerais/sangue , Estado Nutricional , Dieta , Padrões Dietéticos
2.
Life Sci Alliance ; 5(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34857647

RESUMO

In Wilson disease, excessive copper accumulates in patients' livers and may, upon serum leakage, severely affect the brain according to current viewpoints. Present remedies aim at avoiding copper toxicity by chelation, for example, by D-penicillamine (DPA) or bis-choline tetrathiomolybdate (ALXN1840), the latter with a very high copper affinity. Hence, ALXN1840 may potentially avoid neurological deterioration that frequently occurs upon DPA treatment. As the etiology of such worsening is unclear, we reasoned that copper loosely bound to albumin, that is, mimicking a potential liver copper leakage into blood, may damage cells that constitute the blood-brain barrier, which was found to be the case in an in vitro model using primary porcine brain capillary endothelial cells. Such blood-brain barrier damage was avoided by ALXN1840, plausibly due to firm protein embedding of the chelator bound copper, but not by DPA. Mitochondrial protection was observed, a prerequisite for blood-brain barrier integrity. Thus, high-affinity copper chelators may minimize such deterioration in the treatment of neurologic Wilson disease.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Cobre/metabolismo , Molibdênio/farmacologia , Penicilamina/farmacologia , Animais , Transporte Biológico , Biomarcadores , Barreira Hematoencefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Sobrevivência Celular , Quelantes/farmacologia , Cobre/efeitos adversos , Cobre/química , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Modelos Moleculares , Tomografia por Emissão de Pósitrons , Ligação Proteica , Ratos , Albumina Sérica/química , Albumina Sérica/metabolismo , Relação Estrutura-Atividade
3.
Dtsch Arztebl Int ; 117(35-36): 575-582, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-33161940

RESUMO

BACKGROUND: In Germany, public interest in a vegan diet is steadily growing. There are, however, no current data on the macro- and micronutrient status of vegans. METHODS: In a cross-sectional study entitled "The Risks and Benefits of a Vegan Diet" (RBVD), we investigated the dietary intake, basic laboratory parameters, vitamin status, and trace-element status of 36 vegans and 36 persons on an omnivorous diet. Each group consisted of 18 men and 18 women aged 30-60. RESULTS: Nearly all the vegans and one-third of the persons on a mixed diet had consumed supplements in the previous 4 weeks. Vegans and nonvegans had similar energy intake but differed in the intake of both macronutrients (e.g., dietary fiber) and micronutrients (e.g., vitamins B12, B2, D, E, and K, as well as folate, iodine, and iron). There were no intergroup differences in the biomarkers of vitamin B12, vitamin D, or iron status. The ferritin values and blood counts indicated iron deficiency in four vegans and three non-vegans. Measurements in 24-hour urine samples revealed lower calcium excretion and markedly lower iodine excretion in vegans compared to non-vegans; in one-third of the vegans, iodine excretion was lower than the WHO threshold value (<20 µg/L) for severe iodine deficiency. CONCLUSION: Vitamin B12 status was similarly good in vegans and non-vegans, even though the vegans consumed very little dietary B12. This may be due to the high rate of supplementation. The findings imply a need to also assure adequate iodine intake in the population, especially among persons on a vegan diet.


Assuntos
Dieta Vegana , Vitaminas , Adulto , Estudos Transversais , Dieta Vegetariana , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Minerais
4.
Nutrients ; 12(3)2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32131476

RESUMO

Soils in Germany are commonly low in selenium; consequently, a sufficient dietary supply is not always ensured. The extent of such provision adequacy is estimated by the optimal effect range of biomarkers, which often reflects the physiological requirement. Preceding epidemiological studies indicate that low selenium serum concentrations could be related to cardiovascular diseases. Inter alia, risk factors for cardiovascular diseases are physical inactivity, overweight, as well as disadvantageous eating habits. In order to assess whether these risk factors can be modulated, a cardio-protective diet comprising fixed menu plans combined with physical exercise was applied in the German MoKaRi (modulation of cardiovascular risk factors) intervention study. We analyzed serum samples of the MoKaRi cohort (51 participants) for total selenium, GPx activity, and selenoprotein P at different timepoints of the study (0, 10, 20, 40 weeks) to explore the suitability of these selenium-associated markers as indicators of selenium status. Overall, the time-dependent fluctuations in serum selenium concentration suggest a successful change in nutritional and lifestyle behavior. Compared to baseline, a pronounced increase in GPx activity and selenoprotein P was observed, while serum selenium decreased in participants with initially adequate serum selenium content. SELENOP concentration showed a moderate positive monotonic correlation (r = 0.467, p < 0.0001) to total Se concentration, while only a weak linear relationship was observed for GPx activity versus total Se concentration (r = 0.186, p = 0.021). Evidently, other factors apart from the available Se pool must have an impact on the GPx activity, leading to the conclusion that, without having identified these factors, GPx activity should not be used as a status marker for Se.


Assuntos
Dieta , Exercício Físico , Estado Nutricional , Selênio/sangue , Selenoproteína P/sangue , Adulto , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares , Feminino , Glutationa Peroxidase/sangue , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Trace Elem Med Biol ; 37: 78-84, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27320638

RESUMO

Thio-dimethylarsinic acid (thio-DMA(V)) is a human urinary metabolite of the class 1 human carcinogen inorganic arsenic as well as of arsenosugars. Thio-DMA(V) exerts strong cellular toxicity, whereas its toxic modes of action are not fully understood. For the first time, this study characterises the impact of a long-term (21days) in vitro incubation of thio-DMA(V) on the expression of selected genes related to cell death, stress response, epigenetics and DNA repair. The observed upregulation of DNMT1 might be a cellular compensation to counterregulate the in a very recent study observed massive global DNA hypomethylation after chronic thio-DMA(V) incubation. Moreover, our data suggest that chronic exposure towards subcytotoxic, pico- to nanomolar concentrations of thio-DMA(V) causes a stress response in human urothelial cells. The upregulation of genes encoding for proteins of DNA repair (Apex1, Lig1, XRCC1, DDB2, XPG, ATR) as well as damage response (GADD45A, GADD45G, Trp53) indicate a potential genotoxic risk emanating from thio-DMA(V) after long-term incubation.


Assuntos
Ácido Cacodílico/análogos & derivados , Reparo do DNA/genética , Perfilação da Expressão Gênica , Reação em Cadeia da Polimerase em Tempo Real , Ácido Cacodílico/toxicidade , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Reparo do DNA/efeitos dos fármacos , Humanos , Membranas Mitocondriais/efeitos dos fármacos
6.
Artigo em Inglês | MEDLINE | ID: mdl-25569887

RESUMO

This paper presents a comparison between two different technologies of acquisition systems (BrainNet36 and Emotiv Epoc) for an Independent-BCI based on Steady-State Visual Evoked Potential (SSVEP). Two stimuli separated by a viewing angle <; 1° were used. Multivariate Synchronization Index (MSI) technique was used as feature extractor and five subjects participated in the experiments. The class is obtained through a criterion of maxima. The left and right flicker stimuli were modulated at frequencies of 8.0 and 13.0 Hz, respectively. Acquisition via BrainNet system showed better results, obtaining the highest value for accuracy (100%) and the highest ITR (35.18 bits/min). This Independent-BCI is based on covert attention.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados Visuais , Adulto , Interfaces Cérebro-Computador , Humanos , Masculino , Exame Neurológico , Estimulação Luminosa , Tecnologia sem Fio
7.
Med Eng Phys ; 35(8): 1155-64, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23339894

RESUMO

This work presents a brain-computer interface (BCI) used to operate a robotic wheelchair. The experiments were performed on 15 subjects (13 of them healthy). The BCI is based on steady-state visual-evoked potentials (SSVEP) and the stimuli flickering are performed at high frequency (37, 38, 39 and 40 Hz). This high frequency stimulation scheme can reduce or even eliminate visual fatigue, allowing the user to achieve a stable performance for long term BCI operation. The BCI system uses power-spectral density analysis associated to three bipolar electroencephalographic channels. As the results show, 2 subjects were reported as SSVEP-BCI illiterates (not able to use the BCI), and, consequently, 13 subjects (12 of them healthy) could navigate the wheelchair in a room with obstacles arranged in four distinct configurations. Volunteers expressed neither discomfort nor fatigue due to flickering stimulation. A transmission rate of up to 72.5 bits/min was obtained, with an average of 44.6 bits/min in four trials. These results show that people could effectively navigate a robotic wheelchair using a SSVEP-based BCI with high frequency flickering stimulation.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Paralisia/reabilitação , Robótica/instrumentação , Córtex Visual/fisiopatologia , Percepção Visual , Cadeiras de Rodas , Adulto , Biorretroalimentação Psicológica/instrumentação , Eletroencefalografia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Sistemas Homem-Máquina , Pessoa de Meia-Idade , Paralisia/fisiopatologia , Estimulação Luminosa/instrumentação , Estimulação Luminosa/métodos , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-22255400

RESUMO

This work presents a robotic wheelchair that can be commanded by a Brain Computer Interface (BCI) through Steady-State Visual Evoked Potential (SSVEP), Motor Imagery and Word Generation. When using SSVEP, a statistical test is used to extract the evoked response and a decision tree is used to discriminate the stimulus frequency, allowing volunteers to online operate the BCI, with hit rates varying from 60% to 100%, and guide a robotic wheelchair through an indoor environment. When using motor imagery and word generation, three mental task are used: imagination of left or right hand, and imagination of generation of words starting with the same random letter. Linear Discriminant Analysis is used to recognize the mental tasks, and the feature extraction uses Power Spectral Density. The choice of EEG channel and frequency uses the Kullback-Leibler symmetric divergence and a reclassification model is proposed to stabilize the classifier.


Assuntos
Potenciais Evocados Visuais , Robótica , Fala , Cadeiras de Rodas , Árvores de Decisões , Análise Discriminante , Eletroencefalografia , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-21096297

RESUMO

Several students of Bioengineering complain about the excess of theoretical classes and the difficulty to assimilate the subject taught. This article presents a strategy to mix theory and practice when teaching, thus motivating students to engage in their studies.


Assuntos
Bioengenharia/métodos
10.
Comput Biol Med ; 38(6): 659-67, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18462711

RESUMO

This work discusses the implementation of incremental hidden Markov model (HMM) training methods for electrocardiogram (ECG) analysis. The HMMs are used to model the ECG signal as a sequence of connected elementary waveforms. Moreover, an adaptation process is implemented to adapt the HMMs to the ECG signal of a particular individual. The adaptation training strategy is based on incremental versions of the expectation-maximization, segmental k-means and Bayesian approaches. Performance of the training methods was assessed through experiments considering the QT and ST-T databases. The results obtained show that the incremental training improves beat segmentation and ischemia detection performance with the advantage of low computational effort.


Assuntos
Algoritmos , Eletrocardiografia/estatística & dados numéricos , Cadeias de Markov , Bases de Dados Factuais , Humanos , Isquemia/diagnóstico , Funções Verossimilhança , Processamento de Sinais Assistido por Computador
11.
AIDS ; 19(7): 734-5, 2005 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-15821402

RESUMO

We report on the first HLA B13-restricted minimal cytotoxic T lymphocyte (CTL) epitope RQDILDLWI (RI9, amino acids 106-114 in HIV-1 Nef). In most patients the frequency of RI9-specific CTL exceeded the number of CTL against other epitopes, indicating that RI9 is a dominant epitope in HLA B13-positive patients. Targeting this conserved Nef epitope may be an important factor for the published association of HLA B13 with a favourable course of HIV-1 infection.


Assuntos
Epitopos de Linfócito T , Produtos do Gene nef , Infecções por HIV/imunologia , HIV-1/imunologia , Antígenos HLA-B , Linfócitos T Citotóxicos/imunologia , Motivos de Aminoácidos , Sequência Consenso , Citotoxicidade Imunológica , Mapeamento de Epitopos , Infecções por HIV/mortalidade , HIV-1/isolamento & purificação , Antígeno HLA-B13 , Humanos , Epitopos Imunodominantes , Taxa de Sobrevida , Produtos do Gene nef do Vírus da Imunodeficiência Humana
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