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1.
BMJ Support Palliat Care ; 10(1): 91-104, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31831511

RESUMO

BACKGROUND: Q3 conditions are progressive, metabolic, neurological or chromosomal childhood conditions without a cure. Children with these conditions face an unknown lifespan as well as unstable and uncomfortable symptoms. Clinicians and other healthcare professionals are challenged by a lack of evidence for symptom management for these conditions. AIMS: In this scoping review, we systematically identified and mapped the existing literature on symptom management for children with Q3 conditions. We focused on the most common and distressing symptoms, namely alertness, behavioural problems, bowel incontinence, breathing difficulties, constipation, feeding difficulties, sleep disturbance, temperature regulation, tone and motor problems and urinary incontinence. For children with complex health conditions, good symptom management is pertinent to ensure the highest possible quality of life. METHODS: Scoping review. Electronic database searches in Ovid MEDLINE, Embase and CINAHL and a comprehensive grey literature search. RESULTS: We included 292 studies in our final synthesis. The most commonly reported conditions in the studies were Rett syndrome (n=69), followed by Cornelia de Lange syndrome (n=25) and tuberous sclerosis (n=16). Tone and motor problems were the most commonly investigated symptom (n=141), followed by behavioural problems (n=82) and sleep disturbance (n=62). CONCLUSION: The evidence for symptom management in Q3 conditions is concentrated around a few conditions, and these studies may not be applicable to other conditions. The evidence is dispersed in the literature and difficult to access, which further challenges healthcare providers. More research needs to be done in these conditions to provide high-quality evidence for the care of these children.


Assuntos
Estado Terminal/psicologia , Cuidados Paliativos/psicologia , Qualidade de Vida , Doenças Raras/psicologia , Adolescente , Criança , Estado Terminal/terapia , Feminino , Humanos , Masculino , Cuidados Paliativos/métodos , Doenças Raras/terapia
2.
CMAJ ; 191(40): E1113-E1114, 2019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591103
3.
Pain ; 160(8): 1698-1707, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31335640

RESUMO

We know little about the safety or efficacy of pharmacological medicines for children and adolescents with chronic pain, despite their common use. Our aim was to conduct an overview review of systematic reviews of pharmacological interventions that purport to reduce pain in children with chronic noncancer pain (CNCP) or chronic cancer-related pain (CCRP). We searched the Cochrane Database of Systematic Reviews, Medline, EMBASE, and DARE for systematic reviews from inception to March 2018. We conducted reference and citation searches of included reviews. We included children (0-18 years of age) with CNCP or CCRP. We extracted the review characteristics and primary outcomes of ≥30% participant-reported pain relief and patient global impression of change. We sifted 704 abstracts and included 23 systematic reviews investigating children with CNCP or CCRP. Seven of those 23 reviews included 6 trials that involved children with CNCP. There were no randomised controlled trials in reviews relating to reducing pain in CCRP. We were unable to combine data in a meta-analysis. Overall, the quality of evidence was very low, and we have very little confidence in the effect estimates. The state of evidence of randomized controlled trials in this field is poor; we have no evidence from randomised controlled trials for pharmacological interventions in children with cancer-related pain, yet cannot deny individual children access to potential pain relief. Prospero ID: CRD42018086900.


Assuntos
Analgésicos/uso terapêutico , Dor Crônica/tratamento farmacológico , Manejo da Dor , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
4.
Sci Rep ; 9(1): 6537, 2019 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-31024057

RESUMO

This work presents a simulation study evaluating relative biological effectiveness at 10% survival fraction (RBE10) of several different positron-emitting radionuclides in heavy ion treatment systems, and comparing these to the RBE10s of their non-radioactive counterparts. RBE10 is evaluated as a function of depth for three positron-emitting radioactive ion beams (10C, 11C and 15O) and two stable ion beams (12C and 16O) using the modified microdosimetric kinetic model (MKM) in a heterogeneous skull phantom subject to a rectangular 50 mm × 50 mm × 60 mm spread out Bragg peak. We demonstrate that the RBE10 of the positron-emitting radioactive beams is almost identical to the corresponding stable isotopes. The potential improvement in PET quality assurance image quality which is obtained when using radioactive beams is evaluated by comparing the signal to background ratios of positron annihilations at different intra- and post-irradiation time points. Finally, the incidental dose to the patient resulting from the use of radioactive beams is also quantified and shown to be negligible.


Assuntos
Radioterapia com Íons Pesados , Método de Monte Carlo , Radioatividade , Simulação por Computador , Relação Dose-Resposta à Radiação , Elétrons , Humanos , Imagens de Fantasmas , Dosagem Radioterapêutica , Eficiência Biológica Relativa
5.
J Palliat Care ; 34(3): 151-159, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30060727

RESUMO

Perinatal palliative care is an emerging area of health care. To date, no published tools assess health-care provider's knowledge and level of comfort in providing such care. A 2-phase study was undertaken to develop and implement a survey to evaluate the self-assessed competency, attitudes, and knowledge of health-care providers working in perinatal palliative care. Phase 1 included a review of the literature and appraisal of palliative and death-related instruments to inform the initial draft of the Perinatal Palliative Care Survey (PPCS). Twenty-four Canadian pediatric palliative care specialists critiqued the PPCS, establishing its face and content validity. Phase 2 involved administering the PPCS at 4 sites across Canada, resulting in 167 responses from nurses, physicians, and midwives. The majority of participants responded that they possessed a degree of comfort in providing perinatal palliative care, particularly with assessing pain (76%), managing pain (69%), assessing other symptoms (85%), and managing other symptoms (78%). Two areas where participants level of confidence or extreme confidence was diminished included having conversations with families about the possibility of their infant dying (55%) and knowing and accessing community palliative care resources (32%). Responses in the knowledge section identified gaps related to opioid use, pharmacological interventions for breathlessness, pain behaviors, and tolerance developed to opioids and sedatives. Eighty-six percent of respondents stated that if education about palliative care was made available, they would participate with priority topics identified as communication with families (75%), managing symptoms (69%), pain management (69%), and ethical issues (66%). The PPCS provides a useful assessment to determine the educational needs of health-care providers delivering perinatal palliative care.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Cuidados Paliativos , Inquéritos e Questionários , Adulto , Idoso , Canadá , Feminino , Humanos , Pessoa de Meia-Idade
6.
Sci Rep ; 8(1): 16257, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30390002

RESUMO

This paper presents Neutron Capture Enhanced Particle Therapy (NCEPT), a method for enhancing the radiation dose delivered to a tumour relative to surrounding healthy tissues during proton and carbon ion therapy by capturing thermal neutrons produced inside the treatment volume during irradiation. NCEPT utilises extant and in-development boron-10 and gadolinium-157-based drugs from the related field of neutron capture therapy. Using Monte Carlo simulations, we demonstrate that a typical proton or carbon ion therapy treatment plan generates an approximately uniform thermal neutron field within the target volume, centred around the beam path. The tissue concentrations of neutron capture agents required to obtain an arbitrary 10% increase in biological effective dose are estimated for realistic treatment plans, and compared to concentrations previously reported in the literature. We conclude that the proposed method is theoretically feasible, and can provide a worthwhile improvement in the dose delivered to the tumour relative to healthy tissue with readily achievable concentrations of neutron capture enhancement drugs.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Radioterapia com Íons Pesados/métodos , Neoplasias/radioterapia , Nêutrons , Prótons , Boro/administração & dosagem , Terapia por Captura de Nêutron de Boro/instrumentação , Simulação por Computador , Relação Dose-Resposta à Radiação , Estudos de Viabilidade , Gadolínio/administração & dosagem , Radioterapia com Íons Pesados/instrumentação , Humanos , Isótopos/administração & dosagem , Modelos Biológicos , Método de Monte Carlo , Imagens de Fantasmas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
7.
Glob Adv Health Med ; 7: 2164956118763523, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29619284

RESUMO

BACKGROUND: The practice of yoga has been shown to improve disease- and treatment-related side effects in the noncurative cancer patient. OBJECTIVE: This user experience study aimed to examine the feasibility and usefulness of a DVD-based yoga program for young adult cancer patients with a noncurative diagnosis. METHODS: Participants were asked to partake in a 7-week DVD-based yoga program and complete measures of program use and usefulness. RESULTS: Nine patients expressed study interest and 5 consented to participate. Four completed the full study protocol. Participants reported being satisfied with the program and described that it provided an opportunity for self-care. Improvements in functional, physical, and spiritual well-being and overall quality of life were found. Barriers included competing time demands and feeling unwell. No adverse events were reported. CONCLUSION: The program was viewed as an accessible and useful activity option; however, a desire for greater social support from relatable others was highlighted.

8.
Cochrane Database Syst Rev ; 7: CD012563, 2017 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-28737843

RESUMO

BACKGROUND: Pain is a common feature of childhood and adolescence around the world, and for many young people, that pain is chronic. The World Health Organization (WHO) guidelines for pharmacological treatments for persisting pain in children acknowledge that pain in children is a major public health concern of high significance in most parts of the world. Views on children's pain have changed over time and relief of pain is now seen as important. In the past, pain was largely dismissed and was frequently left untreated, and it was assumed that children quickly forgot about painful experiences.We designed a suite of seven reviews in chronic non-cancer pain and cancer pain (looking at antidepressants, antiepileptic drugs, non-steroidal anti-inflammatory drugs, opioids, and paracetamol as priority areas) to review the evidence for children's pain using pharmacological interventions.As one of the leading causes of mortality and morbidity for children and adolescents in the world today, childhood cancer (and its associated pain) is a major health concern. Specific mortality and morbidity data relating to children are not currently identified. All childhood cancer rates are on the rise; for example, in the USA approximately 10,380 children aged under 15 years were expected to be diagnosed with cancer by the end of 2016. However, with survival rates also increasing, over 80% of paediatric cancer patients are expected to survive for five years or more, thus identifying the need to address pain management in this population.Cancer pain in infants, children, and adolescents is primarily nociceptive pain with negative long term effects. Cancer-related pain is generally caused directly by the tumour itself such as compressing on the nerve or inflammation of the organs. Cancer-related pain generally occurs as a result of perioperative procedures, nerve damage caused by radiation or chemotherapy treatments, or mucositis. However, this review focused on pain caused directly by the tumour itself such as nerve infiltration, external nerve compression, and other inflammatory events.Non-steroidal anti-inflammatory drugs (NSAIDs) are used to treat pain, reduce fever, and for their anti-inflammatory properties. They are commonly used within paediatric pain management. NSAIDs are currently licensed for use in western countries, however not approved for infants aged under three months. Primary adverse effects include gastrointestinal issues and possible renal impairment with long term use. Other adverse effects in children include diarrhoea, headache, nausea, constipation, rash, dizziness, and abdominal pain. OBJECTIVES: To assess the analgesic efficacy, and adverse events, of non-steroidal anti-inflammatory drugs (NSAIDs) used to treat cancer-related pain in children and adolescents aged from birth and 17 years, in any setting. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online, MEDLINE via Ovid, and Embase via Ovid from inception to 21 February 2017. We also searched the reference lists of retrieved studies and reviews, and searched online clinical trial registries. SELECTION CRITERIA: Randomised, double-blind trials of any dose, and any route, treating cancer-related pain in children and adolescents, comparing NSAIDs with placebo or an active comparator. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for eligibility. We planned to use dichotomous data to calculate risk ratio and number needed to treat for one additional event, using standard methods. We assessed GRADE (Grading of Recommendations Assessment, Development and Evaluation) and planned to create a 'Summary of findings' table. MAIN RESULTS: No studies were eligible for inclusion in this review (very low quality evidence). We downgraded the quality of evidence by three levels due to the lack of data reported for any outcome. AUTHORS' CONCLUSIONS: There is no evidence from randomised controlled trials that non-steroidal anti-inflammatory drugs (NSAIDs) reduce cancer-related pain in children and adolescents. This means that no reliance or conclusions can be made about efficacy or harm in the use of NSAIDs to treat chronic cancer-related pain in children and adolescents.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Dor do Câncer/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
9.
Cochrane Database Syst Rev ; 7: CD012564, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28722116

RESUMO

BACKGROUND: Pain is a common feature of childhood and adolescence around the world, and for many young people, that pain is chronic. The World Health Organization (WHO) guidelines for pharmacological treatments for children's persisting pain acknowledge that pain in children is a major public health concern of high significance in most parts of the world. Views on children's pain have changed over time and relief of pain is now seen as important. In the past, pain was largely dismissed and was frequently left untreated, and it was assumed that children quickly forgot about painful experiences.We designed a suite of seven reviews in chronic non-cancer pain and cancer pain (looking at antidepressants, antiepileptic drugs, non-steroidal anti-inflammatory drugs, opioids, and paracetamol) to review the evidence for children's pain using pharmacological interventions.As one of the leading causes of mortality and morbidity for children and adolescents in the world today, childhood cancer (and its associated pain) is a major health concern. Cancer pain in infants, children, and adolescents is primarily nociceptive pain with negative long term effects. Cancer-related pain is generally caused directly by the tumour itself such as compressing on the nerve or inflammation of the organs. Cancer-related pain generally occurs as a result of perioperative procedures, nerve damage caused by radiation or chemotherapy treatments, or mucositis. However, this review focused on pain caused directly by the tumour itself such as nerve infiltration, external nerve compression, and other inflammatory events.Opioids are used worldwide for the treatment of pain. Currently available opioids include: buprenorphine, codeine, fentanyl, hydromorphone, methadone, morphine, oxycodone, and tramadol. Opioids are generally available in healthcare settings across most developed countries but access may be restricted in developing countries. To achieve adequate pain relief in children using opioids, with an acceptable grade of adverse effects, the recommended method is to start with a low dose gradually titrated to effect or unacceptable adverse effect in the child. OBJECTIVES: To assess the analgesic efficacy, and adverse events, of opioids used to treat cancer-related pain in children and adolescents aged between birth and 17 years, in any setting. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online, MEDLINE via Ovid and Embase via Ovid from inception to 22 February 2017. We also searched the reference lists of retrieved studies and reviews, and searched online clinical trial registries. SELECTION CRITERIA: Randomised controlled trials (RCTs), with or without blinding, of any dose, and any route, treating cancer-related pain in children and adolescents, comparing opioids with placebo or an active comparator. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for eligibility. We planned to use dichotomous data to calculate risk ratio and number needed to treat for one additional event, using standard methods. We assessed GRADE (Grading of Recommendations Assessment, Development and Evaluation) and planned to create a 'Summary of findings' table. MAIN RESULTS: No studies were identified that were eligible for inclusion in this review (very low quality evidence). Several studies tested opioids on adults with cancer-related pain, but none in participants aged from birth to 17 years.We rated the quality of evidence as very low, downgraded due to a lack of available data; no analyses could be undertaken. AUTHORS' CONCLUSIONS: No conclusions can be drawn about efficacy or harm in the use of opioids to treat cancer-related pain in children and adolescents. As a result, there is no RCT evidence to support or refute the use of opioids to treat cancer-related pain in children and adolescents.


Assuntos
Analgésicos Opioides/uso terapêutico , Dor do Câncer/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido
10.
J Med Chem ; 58(15): 6214-24, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26177000

RESUMO

This study reports the synthesis, [(123)I]radiolabeling, and biological profile of a new series of iodinated compounds for potential translation to the corresponding [(131)I]radiolabeled compounds for radionuclide therapy of melanoma. Radiolabeling was achieved via standard electrophilic iododestannylation in 60-90% radiochemical yield. Preliminary SPECT imaging demonstrated high and distinct tumor uptake of all compounds, as well as high tumor-to-background ratios compared to the literature compound [(123)I]4 (ICF01012). The most favorable compounds ([(123)I]20, [(123)I]23, [(123)I]41, and [(123)I]53) were selected for further biological investigation. Biodistribution studies indicated that all four compounds bound to melanin containing tissue with low in vivo deiodination; [(123)I]20 and [(123)I]53 in particular displayed high and prolonged tumor uptake (13% ID/g at 48 h). [(123)I]53 had the most favorable overall profile of the cumulative uptake over time of radiosensitive organs. Metabolite analysis of the four radiotracers found [(123)I]41 and [(123)I]53 to be the most favorable, displaying high and prolonged amounts of intact tracer in melanin containing tissues, suggesting melanin specific binding. Results herein suggest that compound [(123)I]53 displays favorable in vivo pharmacokinetics and stability and hence is an ideal candidate to proceed with further preclinical [(131)I] therapeutic evaluation.


Assuntos
Radioisótopos do Iodo/química , Radioisótopos do Iodo/uso terapêutico , Melaninas/química , Melanoma/radioterapia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Tomografia Computadorizada de Emissão de Fóton Único
11.
EJNMMI Res ; 5: 9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25853015

RESUMO

BACKGROUND: Recent research has demonstrated the potential of 18-kDa translocator protein (TSPO) to serve as a target for nuclear imaging of gliomas. The aim of this study was to evaluate SPECT imaging of GL26 mouse glioma using radioiodinated CLINDE, a TSPO-specific tracer. METHODS: GL26 cells, previously transfected with an enhanced green fluorescent protein (EGFP)-expressing lentivirus, were stereotactically implanted in the striatum of C57/Bl6 mice. At 4 weeks post-injection, dynamic SPECT scans with [(123)I]CLINDE were performed. A displacement study assessed specificity of tracer binding. SPECT images were compared to results of autoradiography, fluorescence microscopy, in situ nucleic acid hybridization, histology, and immunohistochemistry. Western blotting was performed to verify TSPO production by the tumor. RESULTS: Specific uptake of tracer by the tumor is observed with a high signal-to-noise ratio. Tracer uptake by the tumor is indeed 3.26 ± 0.32 times higher than that of the contralateral striatum, and 78% of the activity is displaceable by unlabeled CLINDE. Finally, TSPO is abundantly expressed by the GL26 cells. CONCLUSIONS: The present study demonstrates the feasibility of [(123)I]CLINDE SPECT in translational studies and underlines its potential for clinical glioma SPECT imaging.

12.
Neuroimage ; 99: 365-76, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24862069

RESUMO

PURPOSE: The partial saturation approach (PSA) is a simple, single injection experimental protocol that will estimate both B(avail) and appK(D) without the use of blood sampling. This makes it ideal for use in longitudinal studies of neurodegenerative diseases in the rodent. The aim of this study was to increase the range and applicability of the PSA by developing a data driven strategy for determining reliable regional estimates of receptor density (B(avail)) and in vivo affinity (1/appK(D)), and validate the strategy using a simulation model. METHODS: The data driven method uses a time window guided by the dynamic equilibrium state of the system as opposed to using a static time window. To test the method, simulations of partial saturation experiments were generated and validated against experimental data. The experimental conditions simulated included a range of receptor occupancy levels and three different B(avail) and appK(D) values to mimic diseases states. Also the effect of using a reference region and typical PET noise on the stability and accuracy of the estimates was investigated. RESULTS: The investigations showed that the parameter estimates in a simulated healthy mouse, using the data driven method were within 10±30% of the simulated input for the range of occupancy levels simulated. Throughout all experimental conditions simulated, the accuracy and robustness of the estimates using the data driven method were much improved upon the typical method of using a static time window, especially at low receptor occupancy levels. Introducing a reference region caused a bias of approximately 10% over the range of occupancy levels. CONCLUSIONS: Based on extensive simulated experimental conditions, it was shown the data driven method provides accurate and precise estimates of B(avail) and appK(D) for a broader range of conditions compared to the original method.


Assuntos
Algoritmos , Encéfalo/diagnóstico por imagem , Antagonistas de Dopamina/administração & dosagem , Tomografia por Emissão de Pósitrons/métodos , Racloprida/administração & dosagem , Compostos Radiofarmacêuticos/administração & dosagem , Receptores de Dopamina D2/metabolismo , Animais , Simulação por Computador , Injeções , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neurodegenerativas/diagnóstico por imagem , Reprodutibilidade dos Testes
13.
Neuroimage ; 97: 29-40, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24742918

RESUMO

Positron emission tomography (PET) with [(11)C]Raclopride is an important tool for studying dopamine D2 receptor expression in vivo. [(11)C]Raclopride PET binding experiments conducted using the Partial Saturation Approach (PSA) allow the estimation of receptor density (B(avail)) and the in vivo affinity appK(D). The PSA is a simple, single injection, single scan experimental protocol that does not require blood sampling, making it ideal for use in longitudinal studies. In this work, we generated a complete Monte Carlo simulated PET study involving two groups of scans, in between which a biological phenomenon was inferred (a 30% decrease of B(avail)), and used it in order to design an optimal data processing chain for the parameter estimation from PSA data. The impact of spatial smoothing, noise removal and image resolution recovery technique on the statistical detection was investigated in depth. We found that image resolution recovery using iterative deconvolution of the image with the system point spread function associated with temporal data denoising greatly improves the accuracy and the statistical reliability of detecting the imposed phenomenon. Before optimisation, the inferred B(avail) variation between the two groups was underestimated by 42% and detected in 66% of cases, while a false decrease of appK(D) by 13% was detected in more than 11% of cases. After optimisation, the calculated B(avail) variation was underestimated by only 3.7% and detected in 89% of cases, while a false slight increase of appK(D) by 3.7% was detected in only 2% of cases. We found during this investigation that it was essential to adjust a factor that accounts for difference in magnitude between the non-displaceable ligand concentrations measured in the target and in the reference regions, for different data processing pathways as this ratio was affected by different image resolutions.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Animais , Simulação por Computador , Interpretação Estatística de Dados , Antagonistas de Dopamina , Processamento de Imagem Assistida por Computador , Camundongos , Método de Monte Carlo , Tomografia por Emissão de Pósitrons/estatística & dados numéricos , Racloprida , Compostos Radiofarmacêuticos , Receptores de Dopamina D2/efeitos dos fármacos , Reprodutibilidade dos Testes
14.
EJNMMI Res ; 3(1): 80, 2013 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-24330526

RESUMO

BACKGROUND: Sigma2 (σ2) receptors are highly expressed in cancer cell lines and in tumours. Two novel selective 18F-phthalimido σ2 ligands, 18F-SIG343 and 18F-SIG353, were prepared and characterised for their potential tumour imaging properties. METHODS: Preparation of 18F-SIG343 and 18F-SIG353 was achieved via nucleophilic substitution of their respective nitro precursors. In vitro studies including radioreceptor binding assays in the rat brain membrane and cell uptake studies in the A375 cell line were performed. In vivo studies were carried out in mice bearing A375 tumours including positron emission tomography (PET) imaging, biodistribution, blocking and metabolite studies. RESULTS: In vitro studies showed that SIG343 and SIG353 displayed excellent affinity and selectivity for σ2 receptors (Ki(σ2) = 8 and 3 nM, σ2:σ1 = 200- and 110-fold, respectively). The σ2 selectivity of 18F-SIG343 was further confirmed by blocking studies in A375 cells, however, not noted for 18F-SIG353. Biodistribution studies showed that both radiotracers had similar characteristics including moderately high tumour uptake (4%ID/g to 5%ID/g); low bone uptake (3%ID/g to 4%ID/g); and high tumour-to-muscle uptake ratios (four- to sevenfold) up to 120 min. Although radiotracer uptake in organs known to express σ receptors was significantly blocked by pre-injection of competing σ ligands, the blocking effect was not observed in the tumour. PET imaging studies indicated major radioactive localisation in the chest cavity for both ligands, with approximately 1%ID/g uptake in the tumour at 120 min. Metabolite studies showed that the original radiotracers remained unchanged 65% to 80% in the tumour up to 120 min. CONCLUSIONS: The lead ligands showed promising in vitro and in vivo characteristics. However, PET imaging indicated low tumour-to-background ratios. Furthermore, we were unable to demonstrate that uptake in the A375 tumour was σ2-specific. 18F-SIG343 and 18F-SIG343 do not display ideal properties for imaging the σ2 receptor in the A375 tumour model. However, since the radiotracers show promising in vitro and in vivo characteristics, longer scans using appropriate half-life isotopes and alternative tumour models will be carried out in future studies to fully validate the imaging characteristics of these radiotracers.

15.
J Nucl Med ; 54(2): 291-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23321458

RESUMO

UNLABELLED: Glial neuroinflammation is associated with the development and progression of multiple sclerosis. PET imaging offers a unique opportunity to evaluate neuroinflammatory processes longitudinally in a noninvasive and clinically translational manner. (18)F-PBR111 is a newly developed PET radiopharmaceutical with high affinity and selectivity for the translocator protein (TSPO), expressed on activated glia. This study aimed to investigate neuroinflammation at different phases of relapsing-remitting (RR) experimental autoimmune encephalomyelitis (EAE) in the brains of SJL/J mice by postmortem histologic analysis and in vivo by PET imaging with (18)F-PBR111. METHODS: RR EAE was induced by immunization with PLP(139-151) peptide in complete Freund's adjuvant. Naive female SJL/J mice and mice immunized with saline-complete Freund's adjuvant were used as controls. The biodistribution of (18)F-PBR111 was measured in 13 areas of the central nervous system and compared with PET imaging results during different phases of RR EAE. The extents of TSPO expression and glial activation were assessed with immunohistochemistry, immunofluorescence, and a real-time polymerase chain reaction. RESULTS: There was significant TSPO expression in all of the central nervous system areas studied at the peak of the first clinical episode and, importantly, at the preclinical stage. In contrast, only a few TSPO-positive cells were observed at the second episode. At the third episode, there was again an increase in TSPO expression. TSPO expression was associated with microglial cells or macrophages without obvious astrocyte labeling. The dynamics of (18)F-PBR111 uptake in the brain, as measured by in vivo PET imaging and biodistribution, followed the pattern of TSPO expression during RR EAE. CONCLUSION: PET imaging with the TSPO ligand (18)F-PBR111 clearly reflected the dynamics of microglial activation in the SJL/J mouse model of RR EAE. The results are the first to highlight the discrepancy between the clinical symptoms of EAE and TSPO expression in the brain, as measured by PET imaging at the peaks of various EAE episodes. The results suggest a significant role for PET imaging investigations of neuroinflammation in multiple sclerosis and allow for in vivo follow-up of antiinflammatory treatment strategies.


Assuntos
Sistema Nervoso Central/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Tomografia por Emissão de Pósitrons/métodos , Receptores de GABA/biossíntese , Animais , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Imuno-Histoquímica/métodos , Inflamação , Macrófagos/citologia , Camundongos , Microscopia de Fluorescência/métodos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Transporte Proteico , Reação em Cadeia da Polimerase em Tempo Real/métodos
16.
Can J Anaesth ; 58(11): 1016-23, 2011 Nov.
Artigo em Francês | MEDLINE | ID: mdl-21887601

RESUMO

PURPOSE: The aim of the study was to test the validity of a French language version of the Non-Communicating Children's Pain Checklist - Postoperative Version (NCCPC-PV): grille d'évaluation de la douleur-déficience intellectuelle (GED-DI). METHODS: We assessed the intensity of pain in 87 intellectually disabled surgical patients recruited in four Canadian and French hospitals in the pre- and post-operative settings using the GED-DI, a 100-mm visual analogue pain scale (VAS) and the Rosen sedation scale. The validity of the GED-DI was measured by the difference in scores between pre- and postoperative conditions. The checklist was made up of 30 items divided into seven subgroups. Items were rated from 0 to 3 for a total score ranging from 0 to 90 points. RESULTS: The mean (standard deviation) age of the patients was 17 (11) yr and the mean mental age 24.5 (24) months. The total GED-DI score was 6.1 (4.9) pre- and 13.4 (11.2) post-surgery (P < 0.001). All subgroups had a higher score after surgery (P < 0.001). The receiver operating characteristic (ROC) curves, comparing the absence of pain to mild pain scores and moderate to severe pain scores, showed a cutoff at 6 (mild pain) and 11 (moderate to severe pain). CONCLUSION: The French version of the NCCPC-PV can be used to assess pain in non-communicating patients with intellectual disabilities in a postoperative setting. It has good content validity, as the total pre-surgery score for the GED-DI was significantly lower than the postoperative score, and showed a good concurrent validity when compared to the VAS.


Assuntos
Medição da Dor , Dor Pós-Operatória/diagnóstico , Adolescente , Adulto , Criança , Comunicação , Crianças com Deficiência , Humanos , Curva ROC
17.
Eur J Nucl Med Mol Imaging ; 38(8): 1516-28, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21484375

RESUMO

PURPOSE: The purpose of this study was to assess the feasibility and sensitivity of the high-affinity translocator protein (TSPO) ligand [(123)I]-CLINDE in imaging TSPO changes in vivo and characterise and compare astroglial and TSPO changes in the cuprizone model of demyelination and remyelination in C57BL/6 mice. METHODS: C57BL/6 mice were fed with cuprizone for 4 weeks to induce demyelination followed by 2-4 weeks of standard diet (remyelination). Groups of mice were followed by in vivo single photon emission computed tomography (SPECT)/CT imaging using [(123)I]-CLINDE and uptake correlated with biodistribution, autoradiography, immunohistochemistry, immunofluorescence and real-time polymerase chain reaction (RT-PCR). RESULTS: The uptake of [(123)I]-CLINDE in the brain as measured by SPECT imaging over the course of treatment reflects the extent of the physiological response, with significant increases observed during demyelination followed by a decrease in uptake during remyelination. This was confirmed by autoradiography and biodistribution studies. A positive correlation between TSPO expression and astrogliosis was found and both activated astrocytes and microglial cells expressed TSPO. [(123)I]-CLINDE uptake reflects astrogliosis in brain structures such as corpus callosum, caudate putamen, medium septum and olfactory tubercle as confirmed by both in vitro and in vivo results. CONCLUSION: The dynamics in the cuprizone-induced astroglial and TSPO changes, observed by SPECT imaging, were confirmed by immunofluorescence, RT-PCR and autoradiography. The highly specific TSPO radioiodinated ligand CLINDE can be used as an in vivo marker for early detection and monitoring of a variety of neuropathological conditions using noninvasive brain imaging techniques.


Assuntos
Astrócitos/diagnóstico por imagem , Astrócitos/patologia , Compostos Bicíclicos Heterocíclicos com Pontes , Cuprizona/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Corpo Caloso/patologia , Inflamação/induzido quimicamente , Inflamação/diagnóstico por imagem , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Traçadores Radioativos , Receptores de GABA/genética , Regulação para Cima/efeitos dos fármacos
18.
J Med Chem ; 54(6): 1860-70, 2011 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-21351733

RESUMO

Interest in radiolabeled amino acids for metabolic imaging of cancer and limitations with [(11)C]methionine has prompted the development of a new (18)F-labeled methionine derivative S-(3-[(18)F]fluoropropyl)homocysteine ([(18)F]FPHCys). The L and D enantiomers of [(18)F]FPHCys were prepared from their respective protected S-(3-tosyloxypropyl)homocysteine precursors 1 by [(18)F]fluoride substitution using K(2.2.2) and potassium oxalate, followed by acid hydrolysis on a Tracerlab FX(FN) synthesis module. [(18)F]-L-FPHCys and [(18)F]-D-FPHCys were isolated in 20 ± 5% radiochemical yield and >98% radiochemical and enantiomeric purity in 65 min. Competitive uptake studies in A375 and HT29 tumor cells suggest that L- and D-[(18)F]FPHCys are taken up by the L-transporter system. [(18)F]-L-FPHCys and [(18)F]-D-FPHCys displayed good stability In Vivo without incorporation into protein at least 2 h postinjection. Biodistribution studies demonstrate good uptake in A375 tumor-bearing rodents with tumor to blood ratios of 3.5 and 5.0 for [(18)F]-L-FPHCys and [(18)F]-D-FPHCys, respectively, at 2 h postinjection.


Assuntos
Homocisteína/análogos & derivados , Neoplasias Experimentais/diagnóstico por imagem , Compostos Radiofarmacêuticos/síntese química , Sistema A de Transporte de Aminoácidos/antagonistas & inibidores , Sistema A de Transporte de Aminoácidos/metabolismo , Sistema L de Transporte de Aminoácidos/antagonistas & inibidores , Sistema L de Transporte de Aminoácidos/metabolismo , Animais , Linhagem Celular Tumoral , Radioisótopos de Flúor , Homocisteína/síntese química , Homocisteína/química , Homocisteína/farmacocinética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Estereoisomerismo , Relação Estrutura-Atividade , Distribuição Tecidual
19.
J Pain Symptom Manage ; 38(6): 837-48, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19819666

RESUMO

Cystic fibrosis (CF) has been transformed from a fatal diagnosis in infancy to a chronic disease of children and young adults. Symptom patterns and disease burden in CF may be shifting to reflect the relatively healthier, older population with the disease. Self-management of symptoms is a hallmark of chronic illness, and yet we do not have a good understanding of how CF patients monitor or manage their symptoms. Children and adults were recruited through clinics in three Canadian provinces. Questionnaires with open-ended and close-ended questions in English and French, designed to assess the frequency, severity, and self-management of pain, breathlessness, and cough, were mailed to all the eligible participants. One hundred twenty-three respondents completed the survey, for a response rate of 64%. Eighty-four percent (103 of 123) of participants reported having pain. They reported an average of 2.1 locations of pain, with headache and abdominal pain most frequently described. Sixty-four percent (76 of 123) of participants reported having breathlessness, and 83% (99 of 123) of participants reported experiencing cough. Sixty-three percent (62 of 99) of participants with cough reported that cough always or sometimes interfered with their sleep. A variety of pharmacological and nonpharmacological treatments were used to manage symptoms. Pain and dyspnea are more common than suspected and a wide variety of pharmacological and nonpharmacological measures are used to treat symptoms. Cough is difficult to assess, but disturbed sleep may be an indicator of cough severity and an important symptom to consider when evaluating the overall burden of illness in those with CF.


Assuntos
Tosse/etiologia , Tosse/terapia , Fibrose Cística/complicações , Fibrose Cística/terapia , Dispneia/etiologia , Dispneia/terapia , Manejo da Dor , Dor/etiologia , Adolescente , Adulto , Canadá/epidemiologia , Criança , Tosse/epidemiologia , Fibrose Cística/epidemiologia , Dispneia/epidemiologia , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Dor/epidemiologia , Autocuidado , Adulto Jovem
20.
J Cereb Blood Flow Metab ; 29(9): 1601-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19491921

RESUMO

Smoking is associated with a lower incidence of Parkinson's disease (PD), which might be related to a neuroprotective action of nicotine. Postmortem studies have shown a decrease of cerebral nicotinic acetylcholine receptors (nAChRs) in PD. In this study, we evaluated the decrease of nAChRs in PD in vivo using positron emission tomography (PET), and we explored the relationship between nAChRs density and PD severity using both clinical scores and the measurement of striatal dopaminergic function. Thirteen nondemented patients with PD underwent two PET scans, one with 6-[(18)F]fluoro-3,4-dihydroxy-L-phenylalanine (6-[(18)F]fluoro-L-DOPA) to measure the dopaminergic function and another with 2-[(18)F]fluoro-3-[2(S)-2-azetidinylmethoxy]pyridine (2-[(18)F]fluoro-A-85380), a radiotracer with high affinity for the nAChRs. Distribution volumes (DVs) of 2-[(18)F]fluoro-A-85380 measured in the PD group were compared with those obtained from six nonsmoking healthy controls, with regions-of-interest and voxel-based approaches. Both analyses showed a significant (P <0.05) decrease of 2-[(18)F]fluoro-A-85380 DV in the striatum (-10%) and substantia nigra (-14.9%) in PD patients. Despite the wide range of PD stages, no correlation was found between DV and the clinical and PET markers of PD severity.


Assuntos
Corpo Estriado/metabolismo , Doença de Parkinson/metabolismo , Receptores Nicotínicos/metabolismo , Substância Negra/metabolismo , Adulto , Idoso , Azetidinas/metabolismo , Dopamina/metabolismo , Feminino , Radioisótopos de Flúor/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Tomografia por Emissão de Pósitrons , Fumar
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