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1.
BMC Public Health ; 24(1): 1836, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982399

RESUMO

BACKGROUND: Some clients who access healthcare services experience problems due to the wider determinants of health which cannot be addressed (solely) by the medical sector. Social Prescribing (SP) addresses clients ' wider health needs and is based on linkworkers who support primary care clients in accessing social, community and voluntary care services that support their needs. Previous literature has provided valuable insights about what works (or not) in an early stage of implementing SP. However, there is limited insight into what works for the implementation of SP towards embedding. This study provides guiding principles by which SP can be successfully implemented towards the embedding stage and identifies which contextual factors and mechanisms influence these guiding principles. METHODS: A Rapid Realist Review was conducted to examine what works, for whom, why, and in which contexts. A local Dutch reference panel consisting of health and care organisations helped to inform the research questions. Additionally, a workshop was held with the panel, to discuss what the international insights mean for their local contexts. This input helped to further refine the literature review's findings. RESULTS: Five guiding principles were identified for successful implementation of SP at the embedding stage: • Create awareness for addressing the wider determinants of health and the role SP services can play; • Ensure health and care professionals build trusting relationships with all involved stakeholders to create a cyclical referral process; • Invest in linkworkers' skills and capacity so that they can act as a bridge between the sectors; • Ensure clients receive appropriate support to improve their self-reliance and increase their community participation; • Invest in the aligning of structures, processes and resources between involved sectors to support the use of SP services. CONCLUSION: To embed SP, structural changes on a system level as well as cultural changes are needed. This will require a shift in attitude amongst health and care professionals as well as clients towards the use, role and benefit of SP services in addressing the wider determinants of health. It will also require policymakers and researchers to involve communities and include their perspectives.


Assuntos
Atenção Primária à Saúde , Humanos , Países Baixos , Determinantes Sociais da Saúde , Acessibilidade aos Serviços de Saúde
2.
BMC Pediatr ; 23(1): 111, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890472

RESUMO

BACKGROUND: Blueberry muffin is a descriptive term for a neonate with multiple purpuric skin lesions. Many causes are known, amongst them life-threatening diseases like congenital infections or leukemia. Indeterminate cell histiocytosis (ICH) is an exceptionally rare cause of blueberry muffin rash. ICH is a histiocytic disorder which can be limited to the skin or can present with systemic involvement. A mutation that has been described in histiocytic disorders is a MAP2K1 mutation. In ICH, this mutation has previously been described in merely one case. CASE PRESENTATION: A term male neonate was admitted to the neonatology ward directly after birth because of a blueberry muffin rash. ICH was diagnosed on skin biopsy. The lesions resolved spontaneously. The patient is currently 3 years old and has had no cutaneous lesions or systemic involvement so far. This disease course is similar to that of the Hashimoto-Pritzker variant of LCH. CONCLUSIONS: ICH can manifest in neonates as resolving skin lesions. It is limited to the skin in most cases, but systemic development is possible. Therefore, it is essential to confirm the diagnosis with a biopsy before the lesions resolve and to monitor these patients closely with routine follow-up.


Assuntos
Exantema , Histiocitose de Células de Langerhans , Púrpura , Dermatopatias , Recém-Nascido , Lactente , Feminino , Humanos , Masculino , Pré-Escolar , Histiocitose de Células de Langerhans/complicações , Histiocitose de Células de Langerhans/diagnóstico , Histiocitose de Células de Langerhans/congênito , Dermatopatias/complicações , Dermatopatias/congênito , Dermatopatias/patologia , Pele , Exantema/etiologia
3.
Clin Infect Dis ; 71(8): e281-e288, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31790556

RESUMO

BACKGROUND: Ciprofloxacin is used as antimicrobial prophylaxis in pediatric acute lymphoblastic leukemia (ALL) to decrease infections with gram-negative bacteria. However, there are no clear guidelines concerning prophylactic dose. AIMS: To determine the pharmacokinetics and pharmacodynamics (PKPD) of ciprofloxacin prophylaxis in a pediatric ALL population. The effect of patient characteristics and antileukemic treatment on ciprofloxacin exposure, the area under the concentration time curve over minimal inhibitory concentration (AUC24/MIC) ratios, and emergence of resistance were studied. METHODS: A total of 615 samples from 129 children (0-18 years) with ALL were collected in a multicenter prospective study. A population pharmacokinetic model was developed. Microbiological cultures were collected prior to and during prophylaxis. An AUC24/MIC of ≥125 was defined as target ratio. RESULTS: A 1-compartment model with zero-order absorption and allometric scaling best described the data. No significant (P < .01) covariates remained after backward elimination and no effect of asparaginase or azoles were found. Ciprofloxacin AUC24 was 16.9 mg*h/L in the prednisone prophase versus 29.3 mg*h/L with concomitant chemotherapy. Overall, 100%, 81%, and 18% of patients at, respectively, MIC of 0.063, 0.125, and 0.25 mg/L achieved AUC24/MIC ≥ 125. In 13% of the patients, resistant bacteria were found during prophylactic treatment. CONCLUSION: Ciprofloxacin exposure shows an almost 2-fold change throughout the treatment of pediatric ALL. Depending on the appropriateness of 125 as target ratio, therapeutic drug monitoring or dose adjustments might be indicated for less susceptible bacteria starting from ≥ 0.125 mg/L to prevent the emergence of resistance and reach required targets for efficacy.


Assuntos
Ciprofloxacina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Área Sob a Curva , Criança , Ciprofloxacina/farmacologia , Ciprofloxacina/uso terapêutico , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estudos Prospectivos
4.
Support Care Cancer ; 28(12): 5983-5993, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32285260

RESUMO

PURPOSE: To assess the impact of maintenance therapy and the additional impact of dexamethasone treatment on cancer-related fatigue and sleep-wake rhythms in pediatric acute lymphoblastic leukemia (ALL) patients and to determine the association between these outcomes. METHODS: A national cohort of pediatric ALL patients (≥ 2 years) was included (± 1 year post-diagnosis). Patients receiving dexamethasone were assessed twice (assessment with and without dexamethasone). Actigraphy assessments were used to calculate sleep-wake outcomes with nonparametric methods. Cancer-related fatigue was assessed with the PedsQL Multidimensional Fatigue Scale. Sleep-wake rhythms and cancer-related fatigue were compared between patients participating in the assessment without dexamethasone and healthy children (linear regression) and between assessments with and without dexamethasone (mixed models). Using linear regression, associations between sleep-wake outcomes and cancer-related fatigue were determined during assessments with and without dexamethasone. RESULTS: Responses were collected for 125 patients (113 assessments with and 81 without dexamethasone). The sleep-wake rhythm was less stable (p = 0.03) and less robust (p = 0.01), with lower physical activity levels (p < 0.001) and higher cancer-related fatigue levels (p < 0.001) in ALL patients compared to healthy children. Physical activity was lower (p = 0.001) and cancer-related fatigue more severe (p ≤ 0.001) during assessments with dexamethasone compared to without dexamethasone. Sleep-wake outcomes were significantly associated with cancer-related fatigue during periods without dexamethasone, but not during periods with dexamethasone. CONCLUSION: Sleep-wake rhythms are disturbed, physical activity levels lower, and cancer-related fatigue levels higher during maintenance therapy. Interventions aimed to enhance sleep-wake rhythms during maintenance therapy could improve cancer-related fatigue. Families should be supported in coping with the additional burden of dexamethasone treatment to improve well-being of ALL patients.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Dexametasona/efeitos adversos , Fadiga/fisiopatologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Transtornos do Sono-Vigília/induzido quimicamente , Sono/efeitos dos fármacos , Actigrafia , Antineoplásicos Hormonais/uso terapêutico , Criança , Pré-Escolar , Dexametasona/uso terapêutico , Feminino , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Transtornos do Sono-Vigília/fisiopatologia
5.
Support Care Cancer ; 28(6): 2867-2873, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31732853

RESUMO

PURPOSE: The aims were to evaluate the construct validity and reliability of the Dutch version of the pediatric-modified Total Neuropathy Score (ped-mTNS) for assessing vincristine-induced peripheral neuropathy (VIPN) in Dutch pediatric oncology patients aged 5-18 years. METHODS: Construct validity (primary aim) of the ped-mTNS was determined by testing hypotheses about expected correlation between scores of the ped-mTNS (range: 0-32) and the Common Terminology Criteria for Adverse Events (CTCAE) (range: 0-18) for patients and healthy controls and by comparing patients and controls regarding their total ped-mTNS scores and the proportion of children identified with VIPN. Inter-rater and intra-rater reliability and measurement error (secondary aims) were assessed in a subgroup of study participants. RESULTS: Among the 112 children (56 patients and 56 age- and gender-matched healthy controls) evaluated, correlation between CTCAE and ped-mTNS scores was as expected (moderate (r = 0.60)). Moreover, as expected, patients had significantly higher ped-mTNS scores and more frequent symptoms of VIPN compared with controls (both p < .001). Reliability as measured within the intra-rater group (n = 10) (intra-class correlation coefficient (ICCagreement) = 0.64, standard error of measurement (SEMagreement) = 2.92, and smallest detectable change (SDCagreement) = 8.1) and within the inter-rater subgroup (n = 10) (ICCagreement = 0.63, SEMagreement = 3.7, and SDCagreement = 10.26) indicates insufficient reliability. CONCLUSION: The Dutch version of the ped-mTNS appears to have good construct validity for assessing VIPN in a Dutch pediatric oncology population, whereas reliability appears to be insufficient and measurement error high. To improve standardization of VIPN assessment in children, future research aimed at evaluating and further optimizing the psychometric characteristics of the ped-mTNS is needed.


Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Psicometria/métodos , Vincristina/efeitos adversos , Adolescente , Criança , Pré-Escolar , Feminino , História do Século XVII , Humanos , Masculino , Doenças do Sistema Nervoso Periférico/induzido quimicamente
6.
Int J Obes (Lond) ; 37(2): 263-71, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22349571

RESUMO

BACKGROUND: High protein (HP) diets during energy restriction have been studied extensively regarding their ability to reduce body fat and preserve lean body mass, but little is known about their effects on protein metabolism in lean tissues. OBJECTIVE: To determine the effects of energy restriction and protein intake on protein anabolism and catabolism in rats. METHODS: For 5 weeks, 56 male Wistar rats were fed an obesity induction (OI) diet . They were then subjected to a 40% energy restriction using the OI diet or a balanced HP diet for 3 weeks, whereas a control group was fed the OI diet ad libitum (n=8 per group). HP-restricted rats were divided into five groups differing only in terms of their protein source: total milk proteins, casein (C), whey (W), a mix of 50% C and W, and soy (n=8). The animals were then killed in the postprandial state and their body composition was determined. Protein synthesis rates were determined in the liver, gastrocnemius and kidney using a subcutaneous (13)C valine flooding dose. mRNA levels were measured for key enzymes involved in the three proteolysis pathways. RESULTS: Energy restriction, but not diet composition, impacted weight loss and adiposity, whereas lean tissue mass (except in the kidney) was not influenced by diet composition. Levels of neoglucogenic amino acids tended to fall under energy restriction (P<0.06) but this was reversed by a high level of protein. The postprandial protein synthesis rates in different organs were similar in all groups. By contrast, mRNA levels encoding proteolytic enzymes rose under energy restriction in the muscle and kidney, but this was counteracted by a HP level. CONCLUSIONS: In adult obese rats, energy restriction but not diet composition affected fat pads and had little impact on protein metabolism, despite marked effects on proteolysis in the kidney and muscle.


Assuntos
Tecido Adiposo/metabolismo , Caseínas/metabolismo , Proteínas Alimentares/metabolismo , Proteínas do Leite/metabolismo , Obesidade/metabolismo , Proteínas de Soja/metabolismo , Tecido Adiposo/patologia , Animais , Composição Corporal , Peso Corporal , Dieta , Modelos Animais de Doenças , Metabolismo Energético , Rim/patologia , Fígado/patologia , Masculino , Músculo Esquelético/patologia , Ratos , Ratos Wistar
7.
Eur Child Adolesc Psychiatry ; 22(7): 443-50, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23296472

RESUMO

INTRODUCTION: A somatic disorder may initially be overlooked when a child presents with psychiatric symptoms. We report two children with anorexia nervosa as initial diagnosis and in whom there was a delay in the final diagnosis of the underlying malignancy. A literature survey was performed including patients under 18 years of age with psychiatric symptoms in whom later on an oncological diagnosis became evident as an explanation. RESULTS: We have found 30 additional cases, with a median delay of 12 months until the diagnosis of the tumour. Overall, 16 boys and 16 girls had a solid tumour: 26 central nervous system tumours, 3 tumours of the gastrointestinal tract and 3 others. In 25 out of 32 patients anorexia nervosa was assumed, although it always appeared to be atypical. Patients younger than 7 years had a significantly longer delay until final diagnosis, while no other patient characteristics correlated with such delay. DISCUSSION: In addition to careful physical (including full neurological) examination, we advise additional neuroimaging especially in each case of atypical presentation of anorexia nervosa, in order to avoid a delay in diagnosis of a possible malignancy. Furthermore, it is desirable to perform a re-examination when a psychiatric disorder does not respond to therapy, in order not to overlook an underlying oncological disease.


Assuntos
Anorexia Nervosa/diagnóstico , Neoplasias/diagnóstico , Adolescente , Anorexia Nervosa/complicações , Criança , Pré-Escolar , Diagnóstico Tardio , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Neoplasias/complicações
9.
Hum Vaccin Immunother ; 18(5): 2066424, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-35704772

RESUMO

Sublingual immunotherapy (SLIT) is a well-tolerated, safe, and effective approach to treating allergic rhinitis (AR). Oralair® is a five-grass pollen SLIT tablet containing natural pollen allergens from five of the major grass species responsible for seasonal AR due to grass pollen allergy. Recommended use is in a pre-coseasonal regimen, starting daily treatment approximately 4 months before the start of the pollen season, with treatment then continued daily throughout the season; treatment should continue for 3-5 y. Clinical efficacy and safety of Oralair® in patients with grass pollen-induced AR has been demonstrated in a comprehensive clinical development program of randomized controlled trials. Effectiveness has been substantiated in subsequent observational studies with sustained efficacy following treatment cessation and a favorable level of adherence, quality of life, benefit, and satisfaction for the patients. Supportive evidence for a benefit in reducing the risk or delaying the development of allergic asthma is emerging.


Assuntos
Rinite Alérgica , Imunoterapia Sublingual , Administração Sublingual , Alérgenos , Antígenos de Plantas , Humanos , Extratos Vegetais , Poaceae , Pólen , Qualidade de Vida , Rinite Alérgica/terapia , Imunoterapia Sublingual/efeitos adversos , Comprimidos , Resultado do Tratamento
10.
Genes Immun ; 10(3): 210-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19129850

RESUMO

The objective of this study was to identify molecular profiles that may distinguish clinical subtypes in systemic sclerosis (SSc). Large-scale gene expression profiling was performed on peripheral blood (PB) from 12 SSc patients and 6 healthy individuals. Significance analysis of microarrays, two-way hierarchical cluster analysis and PANTHER (Protein ANalysis THrough Evolutionary Relationships) ontology classification were used to analyze the data. Quantitative PCR was applied for validation in a cohort of 43 SSc patients. The results show that the expression of genes involved in immune defense, cell cycle and signal transduction was significantly elevated in PB of SSc patients (n=12) compared with healthy individuals (n=6). SSc patients could be stratified into subgroups based on differential expression of genes induced by type I interferon (IFN) and genes involved in antimicrobial (AM) activity. Differential expression of type I IFN or AM signature genes was validated and extended in an independent cohort of 31 patients by quantitative PCR. Low expression of IFN response genes was associated with the presence of anti-centromere antibodies, whereas increased expression was associated with the appearance of digital ulcers. In conclusion, patients with SSc can be classified on the basis of differential expression of immune defense genes. Differences in the activity of the type I IFN response program stratify patients into two clinically relevant subgroups.


Assuntos
Anticorpos Antinucleares/imunologia , Centrômero/imunologia , Interferon Tipo I/genética , Escleroderma Sistêmico/genética , Úlcera Cutânea/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Feminino , Dedos , Perfilação da Expressão Gênica , Humanos , Interferon Tipo I/imunologia , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/classificação , Escleroderma Sistêmico/imunologia , Úlcera Cutânea/imunologia , Regulação para Cima/genética , Regulação para Cima/imunologia
11.
Phys Med Biol ; 64(9): 095004, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30917353

RESUMO

Hybrid MR-linac systems enable intrafraction motion monitoring during radiation therapy. Since time-resolved 3D MRI is still challenging, various motion models have been developed that rely on time-resolved 2D imaging. Continuous validation of these models is important for accurate dose accumulation mapping. In this study we used 2D simultaneous multislice (SMS) imaging to improve the PCA-based motion modeling method developed previously (Stemkens et al 2016 Phys. Med. Biol. 61 5335-55). From the additional simultaneously acquired slices, several independent motion models could be generated, which allowed for an assessment of the sensitivity of the motion model to the location of the time-resolved 2D slices. Additionally, the best model could be chosen at every time-point, increasing the method's robustness. Imaging experiments were performed in six healthy volunteers using three simultaneous slices, which generated three independent models per volunteer. For each model the motion traces of the liver tip and both kidneys were estimated. We found that the location of the 2D slices influenced the model's error in five volunteers significantly with a p -value <0.05, and that selecting the best model at every time-point can improve the method. This allows for more accurate and robust motion characterization in MR-guided radiotherapy.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Modelos Biológicos , Movimento , Aceleradores de Partículas , Doses de Radiação , Radioterapia Guiada por Imagem/métodos , Fracionamento da Dose de Radiação , Voluntários Saudáveis , Humanos , Fígado/diagnóstico por imagem , Fígado/efeitos da radiação , Imagens de Fantasmas
12.
Phys Med Biol ; 63(15): 155023, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-29995645

RESUMO

Hybrid MR-linac systems can use fast dynamic MR sequences for tumor tracking and adapt the radiation treatment in real-time. For this the imaging latency must be as short as possible. This work describes how different acquisition parameters influence this latency. First, the latency was measured for Cartesian readouts with phase encode orderings linear, reverse-linear, and high-low. Second, the latency was measured for radial readouts with linear and golden angle profile orderings. To reduce the latency, a spatio-temporal (k-t) filter that suppresses the k-space center of earlier acquired spokes was implemented for the golden angle sequence. For Cartesian readouts a high-low ordering achieved a three times lower latency compared to a linear ordering with our sampling parameters. For radial readouts the filter was able to reduce the acquisition latency from half the acquisition time to a quarter of the acquisition time. The filter did not compromise the signal-to-noise ratio and the artifact power.


Assuntos
Imageamento por Ressonância Magnética/métodos , Radioterapia Guiada por Imagem/métodos , Humanos , Imageamento por Ressonância Magnética/normas , Radioterapia Guiada por Imagem/normas , Razão Sinal-Ruído , Tempo
13.
Oncogene ; 25(49): 6447-56, 2006 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16878161

RESUMO

Nonsteroidal anti-inflammatory drugs show chemopreventive efficacy in colon cancer, but the mechanism behind this remains unclear. Elucidating this mechanism is seen as vital to the development of new chemopreventive agents. We studied the effects of aspirin on the oncogenic Wnt/beta-catenin pathway activity in colorectal cancer cell lines and observed that aspirin dose-dependently decreased the activity of this pathway, as judged by TCF-driven luciferase activity, reduced Wnt target gene expression and increased phosphorylation of beta-catenin by immunoblotting. Furthermore, the ubiquitination and cytoplasmic levels of beta-catenin were assessed by immunoblotting, and also the localization of beta-catenin was shown by green fluorescent protein-tagged beta-catenin and time-lapse fluorescent imaging. Importantly, aspirin treatment caused increased phosphorylation of protein phosphatase 2A (PP2A), an event associated with inhibition of PP2A enzymatic activity, which was confirmed by a reduction in enzymatic PP2A activity. Moreover, this inhibition of PP2A enzymatic activity was essential for the effects of aspirin on the Wnt/beta-catenin pathway as shown by transient transfection with PP2A constructs. The findings in this article provide a molecular explanation for the efficacy of aspirin in chemoprevention of colorectal cancer and shows biochemical evidence that PP2A is an important regulator of Wnt/beta-catenin pathway activity in these cells.


Assuntos
Aspirina/farmacologia , Fosfoproteínas Fosfatases/fisiologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Ciclossomo-Complexo Promotor de Anáfase , Anti-Inflamatórios não Esteroides/farmacologia , Citoplasma/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Reporter/efeitos dos fármacos , Células HCT116 , Humanos , Fosfoproteínas Fosfatases/metabolismo , Fosforilação/efeitos dos fármacos , Proteína Fosfatase 2 , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Fatores de Transcrição TCF/metabolismo , Células Tumorais Cultivadas , Ubiquitina/metabolismo , Complexos Ubiquitina-Proteína Ligase/genética
15.
Int J Med Inform ; 76(4): 297-305, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16533618

RESUMO

PURPOSES: The development of a national protocol to formalize the screening of Dutch cancer survivors on potential late cancer treatment effects and the medical terminology used in describing the patient follow up procedures. METHODS: A combined evidence-based and qualitative approach, the Glaser's State of the Art Strategy, was used to reach consensus on how to screen Dutch cancer survivors on late cancer treatment effects. A core working group set up a first proposal of a screening protocol and a handbook of medical term definitions by incorporating available research evidence (1980-2003), clinical expertise and definitions from Dutch medical dictionaries and textbooks. External experts reviewed this proposal in a cycle of two postal and two discussion rounds. The follow-up procedures and medical term definitions described in the draft screening protocol were to be accepted if consensus among external experts was > or =50%. RESULTS: A protocol for screening cancer survivors on late cancer treatment effects was developed describing the follow-up procedures for cancer survivors according to previous therapeutic exposures. Four hundred and twenty one medical terms were used in describing these follow-up procedures. One hundred and fifteen of these terms were classified as multi-interpretable and 101 of these terms were defined. No definitions could be found for the remaining 14 medical terms. CONCLUSIONS: We succeeded in reaching consensus throughout The Netherlands on a protocol to screen cancer survivors on late cancer treatment effects. This protocol is now in use by all Dutch outpatient clinics and warrants that the screening of cancer survivors is consistent across The Netherlands. The screening protocol specifies in detail how screening of cancer survivors should take place and can therefore be used by clinicians who were not involved in the consensus study.


Assuntos
Programas de Rastreamento/normas , Neoplasias/terapia , Sobrevida , Protocolos Antineoplásicos , Medicina Baseada em Evidências , Humanos , Sistemas Computadorizados de Registros Médicos , Países Baixos , Pacientes Ambulatoriais , Pediatria , Garantia da Qualidade dos Cuidados de Saúde , Resultado do Tratamento
16.
Mol Imaging Biol ; 19(5): 683-693, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28213832

RESUMO

PURPOSE: The combination of ultrasound and microbubbles can facilitate cellular uptake of (model) drugs via transient permeabilization of the cell membrane. By using fluorescent molecules, this process can be studied conveniently with confocal fluorescence microscopy. This study aimed to investigate the relation between cellular uptake and fluorescence intensity increase of intercalating model drugs. PROCEDURES: SYTOX Green, an intercalating fluorescent dye that displays >500-fold fluorescence enhancement upon binding to nucleic acids, was used as a model drug for ultrasound-induced cellular uptake. SYTOX Green uptake was monitored in high spatiotemporal resolution to qualitatively assess the relation between uptake and fluorescence intensity in individual cells. In addition, the kinetics of fluorescence enhancement were studied as a function of experimental parameters, in particular, laser duty cycle (DC), SYTOX Green concentration and cell line. RESULTS: Ultrasound-induced intracellular SYTOX Green uptake resulted in local fluorescence enhancement, spreading throughout the cell and ultimately accumulating in the nucleus during the 9-min acquisition. The temporal evolution of SYTOX Green fluorescence was substantially influenced by laser duty cycle: continuous laser (100 % DC) induced a 6.4-fold higher photobleaching compared to pulsed laser (3.3 % DC), thus overestimating the fluorescence kinetics. A positive correlation of fluorescence kinetics and SYTOX Green concentration was found, increasing from 0.6 × 10-3 to 2.2 × 10-3 s-1 for 1 and 20 µM, respectively. Finally, C6 cells displayed a 2.4-fold higher fluorescence rate constant than FaDu cells. CONCLUSIONS: These data show that the temporal behavior of intracellular SYTOX Green fluorescence enhancement depends substantially on nuclear accumulation and not just on cellular uptake. In addition, it is strongly influenced by the experimental conditions, such as the laser duty cycle, SYTOX Green concentration, and cell line.


Assuntos
Substâncias Intercalantes/metabolismo , Microbolhas , Microscopia de Fluorescência/métodos , Ultrassom , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Sobrevivência Celular , Humanos , Cinética , Compostos Orgânicos/metabolismo , Fotodegradação , Processamento de Sinais Assistido por Computador
17.
PLoS One ; 12(1): e0171138, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28141852

RESUMO

BACKGROUND: Complications might occur after great vessel stent implantation in children. Therefore follow-up using imaging is warranted. PURPOSE: To determine the optimal imaging modality for the assessment of stents used to treat great vessel obstructions in children. MATERIAL AND METHODS: Five different large vessel stents were evaluated in an in-vitro setting. All stents were expanded to the maximal vendor recommended diameter (20mm; n = 4 or 10mm; n = 1), placed in an anthropomorphic chest phantom and imaged with a 256-slice CT-scanner. MRI images were acquired at 1.5T using a multi-slice T2-weighted turbo spin echo, an RF-spoiled three-dimensional T1-weighted Fast Field Echo and a balanced turbo field echo 3D sequence. Two blinded observers assessed stent lumen visibility (measured diameter/true diameter *100%) in the center and at the outlets of the stent. Reproducibility of diameter measurements was evaluated using the intraclass correlation coefficient for reliability and 95% limits of agreement for agreement analysis. RESULTS: Median stent lumen visibility was 88 (IQR 86-90)% with CT for all stents at both the center and outlets. With MRI, the T2-weighted turbo spin echo sequence was preferred which resulted in 82 (78-84%) stent lumen visibility. Interobserver reliability and agreement was good for both CT (ICC 0.997, mean difference -0.51 [-1.07-0.05] mm) and MRI measurements (ICC 0.951, mean difference -0.05 [-2.52 --2.41] mm). CONCLUSION: Good in-stent lumen visibility was achievable in this in-vitro study with both CT and MRI in different great vessel stents. Overall reliability was good with clinical acceptable limits of agreement for both CT and MRI. However, common conditions such as in-stent stenosis and associated aneurysms were not tested in this in-vitro study, limiting the value of the in-vitro study.


Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Stents , Tomografia Computadorizada por Raios X/métodos , Criança , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
18.
J Agric Food Chem ; 54(14): 5197-202, 2006 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-16819935

RESUMO

The effect of a commercial Phaseolus vulgaris extract (PVE, starch stopper) on ileal and fecal endogenous protein losses was studied. Growing rats were fed for 14 days a protein-free diet containing PVE at a nutritional concentration of 0% (PF1), 0.4% (PF2), or 1.1% PVE (PF3) or 1.1% autoclaved PVE (PF4). An indigestible marker (TiO(2)) was included in each diet. Ileal endogenous amino acid (AA) losses were significantly higher (P < 0.05) in PF3 (20% higher than in PF1), except for Pro, Gly, Ala, and His. Endogenous ileal N losses were 22% higher in PF3 than in PF1. Endogenous fecal AA and N losses were all significantly higher (P < 0.05) in PF3. Starch digestibility ( approximately 100%), food intake (single daily meal, d10-23), and body weight loss were not significantly different among the groups. PVE, at 1.1% of the diet, not only was ineffective in reducing starch digestibility but also led to increased ileal endogenous N losses, possibly due to the antinutritional factors (trypsin inhibitor, lectin) present in the PVE.


Assuntos
Aminoácidos/metabolismo , Íleo/efeitos dos fármacos , Íleo/metabolismo , Phaseolus/química , Extratos Vegetais/farmacologia , Proteínas/metabolismo , Animais , Digestão , Fezes/química , Íleo/crescimento & desenvolvimento , Masculino , Nitrogênio/metabolismo , Ratos , Ratos Sprague-Dawley , Amido/metabolismo
19.
Structure ; 9(8): 707-16, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11587645

RESUMO

BACKGROUND: FhuA, an integral membrane protein of Escherichia coli, actively transports ferrichrome and the structurally related antibiotic albomycin across the outer membrane. The transport is coupled to the proton motive force, which energizes FhuA through the inner-membrane protein TonB. FhuA also transports the semisynthetic rifamycin derivative CGP 4832, although the chemical structure of this antibiotic differs markedly from that of ferric hydroxamates. RESULTS: X-ray crystallography revealed that rifamycin CGP 4832 occupies the same ligand binding site as ferrichrome and albomycin, thus demonstrating a surprising lack of selectivity. However, the binding of rifamycin CGP 4832 is deviant from the complexes of FhuA with hydroxamate-type ligands in that it does not result in the unwinding of the switch helix but only in its destabilization, as reflected by increased B factors. Unwinding of the switch helix is proposed to be required for efficient binding of TonB to FhuA and for coupling the proton motive force of the cytoplasmic membrane with energy-dependent ligand transport. The transport data from cells expressing mutant FhuA proteins indicated conserved structural and mechanistic requirements for the transport of both types of compounds. CONCLUSIONS: We conclude that the binding of rifamycin CGP 4832 destabilizes the switch helix and promotes the formation of a transport-competent FhuA-TonB complex, albeit with lower efficiency than ferrichrome. Active transport of this rifamycin derivative explains the 200-fold increase in potency as compared to rifamycin, which is not a FhuA-specific ligand and permeates across the cell envelope by passive diffusion only.


Assuntos
Proteínas da Membrana Bacteriana Externa/química , Proteínas de Escherichia coli/química , Receptores Virais/química , Rifamicinas/química , Rifamicinas/farmacologia , Sítio Alostérico , Proteínas de Bactérias/química , Sítios de Ligação , Transporte Biológico , Transporte Biológico Ativo , Membrana Celular/metabolismo , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Escherichia coli/química , Ferricromo/química , Ligantes , Proteínas de Membrana/química , Modelos Moleculares , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Espectrometria de Fluorescência , Fatores de Tempo , Triptofano/química
20.
Ned Tijdschr Geneeskd ; 150(14): 799-803, 2006 Apr 08.
Artigo em Holandês | MEDLINE | ID: mdl-16649400

RESUMO

A 2-year-old boy presented with acute cerebellar ataxia without opsoclonus. The ataxia was assumed to be post-viral. After a period of years a neuroblastoma was detected. Treatment with a curative intent was successful and consisted of metaiodobenzylguanidine I 131, chemotherapy, tumour resection, chemotherapy again and follow-up treatment with isotretinoin after irradiation. In the literature, 5 other children have been described with acute cerebellar ataxia without opsoclonus in whom neuroblastoma was detected eventually. The mean age of these children at initial presentation was 26 months. The mean time between initial presentation and diagnosis ofneuroblastoma or ganglioneuroblastoma was 12 months. Urine concentrations of catecholamine metabolites were normal in 5 of the 6 total children; concentrations were elevated in 1 child. The tumour was located paravertebrally in 5 of the 6 children. Ataxia resolved following resection of the neuroblastoma in all patients. Each child with prolonged or recurrent acute cerebellar ataxia should be extensively investigated for the presence of neuroblastoma, even in the absence of opsoclonus.


Assuntos
Ataxia Cerebelar/etiologia , Neoplasias do Mediastino/complicações , Neuroblastoma/complicações , Doença Aguda , Pré-Escolar , Humanos , Masculino , Neoplasias do Mediastino/diagnóstico , Neoplasias do Mediastino/terapia , Neuroblastoma/diagnóstico , Neuroblastoma/terapia , Transtornos da Motilidade Ocular/epidemiologia
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