Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Attach Hum Dev ; 25(3-4): 353-367, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37078577

RESUMO

A better understanding of protective factors against childhood depression may allow for the mitigation of severe and chronic symptoms and the timely implementation of intervention strategies. This study investigated the protective effect of having a secure base script on depressive symptoms when children face daily stressors. To test this hypothesis, moderation analyses were performed in a cross-sectional study with 378 children (48.5% boys, 51.5%) aged 8-12 years (M = 10.20; SD = 0.57). The results provided some support for the moderation effect when secure base script knowledge was investigated as a categorical variable in middle childhood. However, the results did not support the moderation effect when investigating secure base script as a continuous variable. Therefore, future investigations may need to address whether a categorical approach could better elucidate the protective role of secure base script knowledge in childhood depression.


Assuntos
Depressão , Apego ao Objeto , Masculino , Humanos , Criança , Feminino , Depressão/epidemiologia , Estudos Transversais , Suscetibilidade a Doenças , Cognição
2.
Attach Hum Dev ; 25(1): 104-116, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-33871320

RESUMO

The current study investigated whether variations at the level of the cortisol stress response moderate the association between parental support and attachment development. To test this hypothesis, we conducted a one-year longitudinal study with two waves in which 101 children (56% girls, Mage = 11.15, SDage = 0.70) participated. Attachment anxiety and avoidance were measured at baseline (Wave 1) and one year later (Wave 2). Parental support and children's cortisol stress response during the Trier Social Stress Test were measured at Wave 2. Children's cortisol stress response was found to moderate the association between parental support and relative change in anxious attachment. A strong cortisol stress response weakened the associated between parental support and relative change in anxious attachment. No moderation effects were found for relative change in avoidant attachment.


Assuntos
Hidrocortisona , Apego ao Objeto , Criança , Feminino , Humanos , Lactente , Masculino , Estudos Longitudinais , Ansiedade , Pais
3.
Food Chem ; 236: 68-75, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28624091

RESUMO

In this study, the molecular mobility of water and biopolymers in coarse, ground, and pericarp-enriched (PE) wheat bran and refined flour was investigated using time-domain proton nuclear magnetic resonance relaxometry, and related to their hydration properties. Several specific proton populations were present in the bran samples but not in flour. These populations were mainly assigned to protons of bran-related compounds such as arabinoxylan, cellulose, and lipids. All bran samples showed similar proton distributions at a 44% moisture level, although the chemical composition of coarse/ground bran and PE bran differed. When bran was further moistened up to 80%, an additional, more mobile water peak was noticed in coarse and PE bran, but not in ground bran. This can be explained by the fact that coarse and PE bran hold more weakly bound water than ground bran, which is most probably water entrapped in between bran particles.


Assuntos
Fibras na Dieta/análise , Triticum/química , Água/química , Biopolímeros , Farinha/análise
4.
Food Chem ; 236: 76-86, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28624092

RESUMO

Water binding is suggested to be key in the deleterious effect of wheat bran on bread quality. This study investigates water mobility and biopolymer behavior during bran-rich bread making and storage, using 1H NMR. Coarse, ground, and pericarp-enriched bran were incorporated in bread dough, and their impact on freshly baked and stored bread properties was assessed. Compared to wheat flour control dough, bran incorporation resulted in a progressive immobilization of water during dough resting, which could be linked to changes in evolution of dough height during fermentation and oven rise. This, together with modified starch gelatinization behavior upon baking, can be related with the inferior quality of bran-rich breads. The impact was most pronounced with pericarp-enriched bran. Textural quality during storage was less affected for coarse or ground bran-rich bread compared to wheat flour bread, which could be principally attributed to retardation of amylopectin retrogradation in the presence of bran.


Assuntos
Pão/análise , Fibras na Dieta/análise , Espectroscopia de Ressonância Magnética/métodos , Água/química , Pão/normas , Farinha , Triticum
5.
Artigo em Inglês | MEDLINE | ID: mdl-28429863

RESUMO

BACKGROUND: Electrical stimulation of the cervical vagus nerve (VNS) prevents postoperative ileus (POI) in mice. As this approach requires an additional cervical procedure, we explored the possibility of peroperative abdominal VNS in mice and human. METHODS: The effect of cervical and abdominal VNS was studied in a murine model of POI and lipopolysaccharide (LPS)-induced sepsis. Postoperative ileus was quantified by assessment of intestinal transit of fluorescent dextran expressed as geometric center (GC). Next, the effect of cervical and abdominal VNS on heart rate was determined in eight Landrace pigs to select the optimal electrode for VNS in human. Finally, the effect of sham or abdominal VNS on LPS-induced cytokine production of whole blood was studied in patients undergoing colorectal surgery. KEY RESULTS: Similar to cervical VNS, abdominal VNS significantly decreased LPS-induced serum tumor necrosis factor-α (TNFα) levels (abdominal VNS: 366±33 pg/mL vs sham: 822±105 pg/mL; P<.01). In line, in a murine model of POI, abdominal VNS significantly improved intestinal transit (GC: sham 5.1±0.2 vs abdominal VNS: 7.8±0.6; P<.01) and reduced intestinal inflammation (abdominal VNS: 35±7 vs sham: 80±8 myeloperoxidase positive cells/field; P<.05). In pigs, heart rate was reduced by cervical VNS but not by abdominal VNS. In humans, abdominal VNS significantly reduced LPS-induced IL8 and IL6 production by whole blood. CONCLUSIONS & INFERENCES: Abdominal VNS is feasible and safe in humans and has anti-inflammatory properties. As abdominal VNS improves POI similar to cervical VNS in mice, our data indicate that peroperative abdominal VNS may represent a novel approach to shorten POI in man.


Assuntos
Íleus/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Estimulação do Nervo Vago/métodos , Animais , Citocinas/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Polipeptídeo Pancreático/sangue , Projetos Piloto , Suínos
6.
Neurogastroenterol Motil ; 27(11): 1542-52, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26227790

RESUMO

BACKGROUND: The orexigenic peptide ghrelin has anti-inflammatory properties in colitis, however, the mechanism of action and the immune cells targeted remain still to be elucidated. Here, we assessed the possible effect of ghrelin on T helper (Th) cells in a T cell transfer model of chronic colitis. METHODS: Disease was induced in the recombination activating gene 1 knockout mice (Rag1(-/-) ) by adoptive transfer of naïve Th cells from ghrelin receptor knockout mice (GRLN-R(-/-) ) or littermate wild-type (WT) mice. The course and severity of colitis was assessed by monitoring body weight, diarrhea score, histological analysis, gene expression, and flow cytometry analysis. The possible effects of ghrelin on Th cell proliferation, polarization, and apoptosis was examined in vitro. KEY RESULTS: Our data showed that Rag1(-/-) mice injected with GRLN-R(-/-) Th cells displayed increased severity of colitis compared to mice injected with WT Th cells. In addition, Rag1(-/-) mice injected with GRLN-R(-/-) Th cells had significantly higher intestinal inflammation and increased accumulation of Th1 and Th17 cells in the colon. In vitro, ghrelin directly affected proliferation of Th cells and induced apoptosis whereas it did not influence Th cell polarization. CONCLUSION & INFERENCES: Our observations suggest that ghrelin modulates Th effector cells in the gut controlling proliferation and inducing apoptosis. Our findings further support the use of ghrelin as a novel therapeutic option to treat intestinal inflammatory diseases.


Assuntos
Colite/imunologia , Receptores de Grelina/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Transferência Adotiva , Animais , Apoptose/imunologia , Proliferação de Células , Modelos Animais de Doenças , Citometria de Fluxo , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real
7.
Int J Obes (Lond) ; 38(4): 547-51, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24335763

RESUMO

OBJECTIVE: The current study investigates the aspects of self-regulation skills in overweight and normal-weight children, which may be related to their overeating problems. It is hypothesised that overweight children may show poor decision-making behaviour, and this may be because of two processes: hypersensitivity to reward or future insensitivity. SUBJECTS: Average weight children (n=66) and overweight children (n=64) between 11 and 16 years were tested with the developmentally appropriate analogue of the Iowa gambling task. RESULTS: The results reveal that overweight children show decision-making failure ensued from future insensitivity. CONCLUSION: These findings provide support for the reward deficiency hypothesis or the anhedonic route to obesity in children.


Assuntos
Comportamento do Adolescente/psicologia , Comportamento Infantil/psicologia , Comportamento de Escolha , Sobrepeso/psicologia , Recompensa , Controles Informais da Sociedade , Adolescente , Análise de Variância , Criança , Tomada de Decisões , Função Executiva , Comportamento Alimentar , Feminino , Jogo de Azar , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Testes Neuropsicológicos , Análise e Desempenho de Tarefas
8.
Strahlenther Onkol ; 188(10): 887-93, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22961046

RESUMO

PURPOSE: The goal of the present study was to analyze long-term results of fractionated stereotactic radiotherapy (SRT) in patients with a meningioma. METHODS AND MATERIALS: A total of 72 patients treated between 1996 and 2008 in MAASTRO clinic (n = 45) and University Hospital Zurich (n = 27) were included. SRT was given as primary treatment (n = 46), postoperatively (n = 19) or at recurrence (n = 7); 49 tumours (68%) were located in the skull base. Median total dose was 54 Gy. RESULTS: Median follow-up was 4.13 years (range 0.66-11 years). The 3- and 5-year overall survival were 92 and 79% for grade 0 and I meningioma. Progression-free survival for grade 0 and I was 95% at 3 and 5 years, and 40% for grade II and III at 3 years. In 98.4% of patients, clinical symptoms were stable or improved. The majority of symptoms improved within 24 months after SRT. Local control is significantly better if patients are irradiated immediately after diagnosis compared to a watchful waiting policy (p = 0.017). Grade IV toxicity was low (4.2%, n = 3) CONCLUSION: SRT is an effective treatment with high local and clinical control. Early SRT resulted in better outcome than late treatment at progression.


Assuntos
Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/radioterapia , Meningioma/diagnóstico , Meningioma/radioterapia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/prevenção & controle , Radiocirurgia/métodos , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Strahlenther Onkol ; 188(1): 84-90, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22194025

RESUMO

PURPOSE: The goal was to provide a quantitative evaluation of the accuracy of three different fixation systems for stereotactic radiotherapy and to evaluate patients' acceptance for all fixations. METHODS: A total of 16 consecutive patients with brain tumours undergoing fractionated stereotactic radiotherapy (SCRT) were enrolled after informed consent (Clinical trials.gov: NCT00181350). Fixation systems evaluated were the BrainLAB® mask, with and without custom made bite-block (fixations S and A) and a homemade neck support with bite-block (fixation B) based on the BrainLAB® frame. The sequence of measurements was evaluated in a randomized manner with a cross-over design and patients' acceptance by a questionnaire. RESULTS: The mean three-dimensional (3D) displacement and standard deviations were 1.16 ± 0.68 mm for fixation S, 1.92 ± 1.28 and 1.70 ± 0.83 mm for fixations A and B, respectively. There was a significant improvement of the overall alignment (3D vector) when using the standard fixation instead of fixation A or B in the craniocaudal direction (p = 0.037). Rotational deviations were significantly less for the standard fixation S in relation to fixations A (p = 0.005) and B (p = 0.03). EPI imaging with off-line correction further improved reproducibility. Five out of 8 patients preferred the neck support with the bite-block. CONCLUSION: The mask fixation system in conjunction with a bite-block is the most accurate fixation for SCRT reducing craniocaudal and rotational movements. Patients favoured the more comfortable but less accurate neck support. To optimize the accuracy of SCRT, additional regular portal imaging is warranted.


Assuntos
Adenoma/cirurgia , Neoplasias Encefálicas/cirurgia , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento Tridimensional/instrumentação , Aceitação pelo Paciente de Cuidados de Saúde , Posicionamento do Paciente/instrumentação , Radiocirurgia/instrumentação , Planejamento da Radioterapia Assistida por Computador/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Artefatos , Astrocitoma/cirurgia , Humanos , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Países Baixos , Neuroma Acústico/cirurgia , Neoplasias Hipofisárias/cirurgia , Estudos Prospectivos , Inquéritos e Questionários
10.
Med Phys ; 35(2): 576-85, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18383679

RESUMO

Respiratory motion in PET and PET/CT blurs the images and can cause attenuation-related errors in quantitative parameters such as standard uptake values. In rare instances, this problem even causes localization errors and the disappearance of tumors that should be detectable. Attenuation errors are severe near the diaphragm and can be enhanced when the attenuation correction is based on a CT series acquired during a breath-hold. To quantify the errors and identify the parameters associated with them, the authors performed a simulated PET scan based on respiratory-gated CT studies of five lung cancer patients. Diaphragmatic motion ranged from 8 to 25 mm in the five patients. The CT series were converted to 511-keV attenuation maps which were forward-projected and exponentiated to form sinograms of PET attenuation factors at each phase of respiration. The CT images were also segmented to form a PET object, moving with the same motion as the CT series. In the moving PET object, spherical 20 mm mobile tumors were created in the vicinity of the dome of the liver and immobile 20 mm tumors in the midchest region. The moving PET objects were forward-projected and attenuated, then reconstructed in several ways: phase-matched PET and CT, gated PET with ungated CT, ungated PET with gated CT, and conventional PET. Spatial resolution and statistical noise were not modeled. In each case, tumor uptake recovery factor was defined by comparing the maximum reconstructed pixel value with the known correct value. Mobile 10 and 30 mm tumors were also simulated in the case of a patient with 11 mm of breathing motion. Phase-matched gated PET and CT gave essentially perfect PET reconstructions in the simulation. Gated PET with ungated CT gave tumors of the correct shape, but recovery was too large by an amount that depended on the extent of the motion, as much as 90% for mobile tumors and 60% for immobile tumors. Gated CT with ungated PET resulted in blurred tumors and caused recovery errors between -50% and +75%. Recovery in clinical scans would be 0%-20% lower than stated because spatial resolution was not included in the simulation. Mobile tumors near the dome of the liver were subject to the largest errors in either case. Conventional PET for 20 mm tumors was quantitative in cases of motion less than 15 mm because of canceling errors in blurring and attenuation, but the recovery factors were too low by as much as 30% in cases of motion greater than 15 mm. The 10 mm tumors were blurred by motion to a greater extent, causing a greater SUV underestimation than in the case of 20 mm tumors, and the 30 mm tumors were blurred less. Quantitative PET imaging near the diaphragm requires proper matching of attenuation information to the emission information. The problem of missed tumors near the diaphragm can be reduced by acquiring attenuation-correction information near end expiration. A simple PET/CT protocol requiring no gating equipment also addresses this problem.


Assuntos
Artefatos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Pulmonares/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Mecânica Respiratória , Técnica de Subtração , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Movimento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Med Phys ; 33(6): 1840-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16872091

RESUMO

The motion of lung tumors with respiration causes difficulties in the imaging with computed tomography (CT) and positronemitted tomography (PET). Since an accurate knowledge of the position of the tumor and the surrounding tissues is needed for radiation treatment planning, it is important to improve CT/PET image acquisition. The purpose of this study was to evaluate the potential to improve image acquisition using phased attenuation correction in respiration correlated CT/PET, where data of both modalities were binned retrospectively. Respiration correlated scans were made on a Siemens Biograph Sensation 16 CT/PET scanner which was modified to make a low pitch CT scan and list mode PET scan possible. A lollipop phantom was used in the experiments. The sphere with a diameter of 3.1 cm was filled with approximately 20 MBq 18F-FDG. Three longitudinal movement amplitudes were tested: 2.5, 3.9, and 4.8 cm. After collection of the raw CT data, list mode PET data, and the respiratory signal CT/PET images were binned to ten phases with the help of in-house-built software. Each PET phase was corrected for attenuation with CT data of the corresponding phase. For comparison, the attenuation correction was also performed with nonrespiration correlated (non-RC) CT data. The volume and the amplitude of the movement were calculated for every phaseof both the CT and PET data (with phased attenuation correction). Maximum and average activity concentrations were compared between the phased and nonphased attenuation corrected PET. With a standard non-RC CT/PET scan, the volume was underestimated by as much as 46% in CT and the PET volume was overestimated to 370%. The volumes found with RC-CT/PET scanning had average deviations of 1.9% (+/- 4.8%) and 1.5% (+/- 3.4%) from the actual volume, for the CT and PET volumes, respectively. Evaluation of the maximum activity concentration showed a clear displacement in the images with non-RC attenuation correction, and activity values were on average14% (+/- 12%) lower than with phased attenuation correction. The standard deviation of the maximum activity values found in the different phases was a factor of 10 smaller when phased attenuation correction was applied. In this phantom study, we have shown that a combination of respiration correlated CT/PET scanning with application of phased attenuation correction can improve the imaging of moving objects and can lead to improved volume estimation and a more precise localization and quantification of the activity.


Assuntos
Aumento da Imagem/métodos , Pulmão/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada de Emissão/métodos , Humanos , Processamento de Imagem Assistida por Computador , Pulmão/fisiologia , Imagens de Fantasmas , Reprodutibilidade dos Testes , Mecânica Respiratória , Sensibilidade e Especificidade
12.
Sci Total Environ ; 272(1-3): 151-8, 2001 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-11379903

RESUMO

This paper describes the new approach to control radiation exposure from natural sources to inhabitants of dwellings that is presently being considered in the Netherlands. The goal of this approach is to uphold the current rather favorable situation (average annual effective dose due to indoor radon and external radiation in dwellings is approx. 1 mSv). To achieve this goal a model is foreseen to predict the potential effective dose an inhabitant may receive from a dwelling on basis of its building plan. A scheme to calculate this dose is proposed in this paper. In future, such a scheme will be included in the Dutch Building Codes and houses to be built will be evaluated by using this scheme and comparing the results with, yet to be posed, limits to the potential effective dose.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Contaminação Radioativa do Ar/análise , Habitação , Poluentes Radioativos do Ar/efeitos adversos , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/prevenção & controle , Contaminação Radioativa do Ar/efeitos adversos , Contaminação Radioativa do Ar/prevenção & controle , Materiais de Construção/efeitos adversos , Materiais de Construção/análise , Raios gama/efeitos adversos , Humanos , Modelos Estatísticos , Países Baixos , Radônio/efeitos adversos , Radônio/análise , Gestão de Riscos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA