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1.
PLoS Pathog ; 20(5): e1011865, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38805482

RESUMO

The role of bacteria in the etiology of dental caries is long established, while the role of fungi has only recently gained more attention. The microbial invasion of dentin in advanced caries especially merits additional research. We evaluated the fungal and bacterial community composition and spatial distribution within carious dentin. Amplicon 16S rRNA gene sequencing together with quantitative PCR was used to profile bacterial and fungal species in caries-free children (n = 43) and 4 stages of caries progression from children with severe early childhood caries (n = 32). Additionally, healthy (n = 10) and carious (n = 10) primary teeth were decalcified, sectioned, and stained with Grocott's methenamine silver, periodic acid Schiff (PAS) and calcofluor white (CW) for fungi. Immunolocalization was also performed using antibodies against fungal ß-D-glucan, gram-positive bacterial lipoteichoic acid, gram-negative endotoxin, Streptococcus mutans, and Candida albicans. We also performed field emission scanning electron microscopy (FESEM) to visualize fungi and bacteria within carious dentinal tubules. Bacterial communities observed included a high abundance of S. mutans and the Veillonella parvula group, as expected. There was a higher ratio of fungi to bacteria in dentin-involved lesions compared to less severe lesions with frequent preponderance of C. albicans, C. dubliniensis, and in one case C. tropicalis. Grocott's silver, PAS, CW and immunohistochemistry (IHC) demonstrated the presence of fungi within carious dentinal tubules. Multiplex IHC revealed that fungi, gram-negative, and gram-positive bacteria primarily occupied separate dentinal tubules, with rare instances of colocalization. Similar findings were observed with multiplex immunofluorescence using anti-S. mutans and anti-C. albicans antibodies. Electron microscopy showed monomorphic bacterial and fungal biofilms within distinct dentin tubules. We demonstrate a previously unrecognized phenomenon in which fungi and bacteria occupy distinct spatial niches within carious dentin and seldom co-colonize. The potential significance of this phenomenon in caries progression warrants further exploration.


Assuntos
Cárie Dentária , Dentina , Humanos , Cárie Dentária/microbiologia , Cárie Dentária/patologia , Dentina/microbiologia , Masculino , Criança , Feminino , Pré-Escolar , Bactérias/genética , Fungos , RNA Ribossômico 16S
2.
J Neurol Neurosurg Psychiatry ; 95(8): 748-752, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38199813

RESUMO

BACKGROUND: Consistent patterns of reduced cortical thickness have been identified in early Alzheimer's disease (AD). However, the pathological factors that influence rates of cortical thinning within these AD signature regions remain unclear. METHODS: Participants were from the Insight 46 substudy of the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort), a prospective longitudinal cohort study. Linear regression was used to examine associations of baseline cerebral ß-amyloid (Aß) deposition, measured using florbetapir positron emission tomography, and baseline white matter hyperintensity volume (WMHV) on MRI, a marker of cerebral small vessel disease, with subsequent longitudinal changes in AD signature cortical thickness quantified from baseline and repeat MRI (mean [SD] interval 2.4 [0.2] years). RESULTS: In a population-based sample of 337 cognitively normal older white adults (mean [SD] age at baseline 70.5 [0.6] years; 48.1% female), higher global WMHV at baseline related to faster subsequent rates of cortical thinning in both AD signature regions (~0.15%/year faster per 10 mL additional WMHV), whereas baseline Aß status did not. Among Aß positive participants (n=56), there was some evidence that greater global Aß standardised uptake value ratio at baseline related to faster cortical thinning in the AD signature Mayo region, but this did not reach statistical significance (p=0.08). CONCLUSIONS: Cortical thinning within AD signature regions may develop via cerebrovascular pathways. Perhaps reflecting the age of the cohort and relatively low prevalence of Aß-positivity, robust Aß-related differences were not detected. Longitudinal follow-up incorporating additional biomarkers will allow assessment of how these relationships evolve closer to expected dementia onset.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Afinamento Cortical Cerebral , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Substância Branca , Humanos , Feminino , Masculino , Idoso , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Estudos Longitudinais , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Afinamento Cortical Cerebral/diagnóstico por imagem , Afinamento Cortical Cerebral/patologia , Estudos Prospectivos , Etilenoglicóis , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Córtex Cerebral/metabolismo , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/patologia , Compostos de Anilina
3.
BMC Neurol ; 24(1): 40, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263061

RESUMO

BACKGROUND: Although age is the biggest known risk factor for dementia, there remains uncertainty about other factors over the life course that contribute to a person's risk for cognitive decline later in life. Furthermore, the pathological processes leading to dementia are not fully understood. The main goals of Insight 46-a multi-phase longitudinal observational study-are to collect detailed cognitive, neurological, physical, cardiovascular, and sensory data; to combine those data with genetic and life-course information collected from the MRC National Survey of Health and Development (NSHD; 1946 British birth cohort); and thereby contribute to a better understanding of healthy ageing and dementia. METHODS/DESIGN: Phase 1 of Insight 46 (2015-2018) involved the recruitment of 502 members of the NSHD (median age = 70.7 years; 49% female) and has been described in detail by Lane and Parker et al. 2017. The present paper describes phase 2 (2018-2021) and phase 3 (2021-ongoing). Of the 502 phase 1 study members who were invited to a phase 2 research visit, 413 were willing to return for a clinic visit in London and 29 participated in a remote research assessment due to COVID-19 restrictions. Phase 3 aims to recruit 250 study members who previously participated in both phases 1 and 2 of Insight 46 (providing a third data time point) and 500 additional members of the NSHD who have not previously participated in Insight 46. DISCUSSION: The NSHD is the oldest and longest continuously running British birth cohort. Members of the NSHD are now at a critical point in their lives for us to investigate successful ageing and key age-related brain morbidities. Data collected from Insight 46 have the potential to greatly contribute to and impact the field of healthy ageing and dementia by combining unique life course data with longitudinal multiparametric clinical, imaging, and biomarker measurements. Further protocol enhancements are planned, including in-home sleep measurements and the engagement of participants through remote online cognitive testing. Data collected are and will continue to be made available to the scientific community.


Assuntos
Demência , Idoso , Feminino , Humanos , Masculino , Envelhecimento , Assistência Ambulatorial , Encéfalo , Estudos Observacionais como Assunto
4.
Eur J Nucl Med Mol Imaging ; 50(4): 980-995, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36469107

RESUMO

PURPOSE: Quantitative SPECT-CT is a modality of growing importance with initial developments in post radionuclide therapy dosimetry, and more recent expansion into bone, cardiac and brain imaging together with the concept of theranostics more generally. The aim of this document is to provide guidelines for nuclear medicine departments setting up and developing their quantitative SPECT-CT service with guidance on protocols, harmonisation and clinical use cases. METHODS: These practice guidelines were written by members of the European Association of Nuclear Medicine Physics, Dosimetry, Oncology and Bone committees representing the current major stakeholders in Quantitative SPECT-CT. The guidelines have also been reviewed and approved by all EANM committees and have been endorsed by the European Association of Nuclear Medicine. CONCLUSION: The present practice guidelines will help practitioners, scientists and researchers perform high-quality quantitative SPECT-CT and will provide a framework for the continuing development of quantitative SPECT-CT as an established modality.


Assuntos
Medicina Nuclear , Humanos , Cintilografia , Medicina Nuclear/métodos , Diagnóstico por Imagem , Radioisótopos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único
5.
Alzheimers Dement ; 19(6): 2750-2754, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36932979

RESUMO

INTRODUCTION: In Alzheimer's disease (AD), hyperphosphorylated tau is closely associated with focal neurodegeneration, but the mechanism remains uncertain. METHODS: We quantified cortical microstructure using neurite orientation dispersion and density imaging in 14 individuals with young onset AD. Diffusion tensor imaging measured mean diffusivity (MD). Amyloid beta and tau positron emission tomography were acquired and associations with microstructural measures were assessed. RESULTS: When regional volume was adjusted for, in the medial temporal lobe there was a significant negative association between neurite density and tau (partial R2  = 0.56, p = 0.008) and between orientation dispersion and tau (partial R2  = 0.66, p = 0.002), but not between MD and tau. In a wider cortical composite, there was an association between orientation dispersion and tau (partial R2  = 0.43, p = 0.030), but not between other measures and tau. DISCUSSION: Our findings are consistent with tau causing first dendritic pruning (reducing dispersion/complexity) followed by neuronal loss. Advanced magnetic resonance imaging (MRI) microstructural measures have the potential to provide information relating to underlying tau deposition.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Neuritos , Imagem de Tensor de Difusão/métodos , Peptídeos beta-Amiloides , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Biomarcadores , Proteínas tau
6.
West Afr J Med ; 40(12 Suppl 1): S25-S26, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38064409

RESUMO

Background and aim: Workplace humanization, when effectively managed can be instrumental in steering an organization towards efficient, and effective work processes. It is on this backdrop that this study aimed at determining the inter-relationship between employee productivity, dignity and empathy. Materials and methods: This was a cross-sectional study that identified the relationship between the study variables. It was conducted among 233 randomly selected employees of private hospitals in Port Harcourt, Rivers State, Nigeria. A self-administered structured questionnaire was used to assess the study variables. Data analysis was conducted using the Statistical Package for Social Sciences (SPSS) software and the relationship between variables tested using the Spearman correlation test. Statistical significance was set at 0.05. Results: The indicators of employee dignity, empathy and productivity were found to have high mean values which were above the threshold of 2.0. A strong positive significant correlation was found to exist between dignity and task accomplishment (r2: 0.796, p-value: <0.001) as well as empathy and task accomplishment (r2: 0.843, p-value: <0.001). Also, a moderate positive statistically significant correlation was found to exist between dignity and service quality (r2=0.373, p-value: <0.001) as well as between employee empathy and service quality (r2= 0.402, p-value: <0.001). Conclusion and Recommendations: The dignity of an employee alongside empathy as measures of work humanization are significant correlates of employee productivity which can be exploited for organizational growth. It is recommended that organizations through institutionalized policies can successfully manage their workplace for optimal productivity via improved employee dignity and empathy as a means of increasing job satisfaction and reduce brain drain.


Assuntos
Empatia , Respeito , Humanos , Estudos Transversais , Nigéria , Hospitais Privados
7.
Eur J Nucl Med Mol Imaging ; 49(6): 1964-1969, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34910233

RESUMO

AIM: Recent advancements in PET technology have brought with it significant improvements in PET performance and image quality. In particular, the extension of the axial field of view of PET systems, and the introduction of semiconductor technology into the PET detector, initially for PET/MR, and more recently available long-field-of-view PET/CT systems (≥ 25 cm) have brought a step change improvement in the sensitivity of PET scanners. Given the requirement to limit paediatric doses, this increase in sensitivity is extremely welcome for the imaging of children and young people. This is even more relevant with PET/MR, where the lack of CT exposures brings further dose reduction benefits to this population. In this short article, we give some details around the benefits around new PET technology including PET/MR and its implications on the EANM paediatric dosage card. MATERIAL AND METHODS : Reflecting on EANM adult guidance on injected activities, and making reference to bed overlap and the concept of MBq.min bed-1 kg-1, we use published data on image quality from PET/MR systems to update the paediatric dosage card for PET/MR and extended axial field of view (≥ 25 cm) PET/CT systems. However, this communication does not cover the expansion of paediatric dosing for the half-body and total-body scanners that have recently come to market. RESULTS: In analogy to the existing EANM dosage card, new parameters for the EANM paediatric dosage card were developed (class B, baseline value: 10.7 MBq, minimum recommended activity 10 MBq). The recommended administered activities for the systems considered in this communication range from 11 MBq [18F]FDG for a child with a weight of 3 kg to 149 MBq [18F]FDG for a paediatric patient weight of 68 kg, assuming a scan of 3 min per bed position. The mean effective dose over all ages (1 year and older) is 2.85 mSv. CONCLUSION: With this, recommendations for paediatric dosing are given for systems that have not been considered previously.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adolescente , Adulto , Criança , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Tecnologia
8.
Epilepsia ; 63(5): 1238-1252, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35166379

RESUMO

OBJECTIVE: 18F-Fluorodeoxyglucose positron emission tomography (FDG-PET) is widely used in presurgical assessment in patients with drug-resistant focal epilepsy (DRE) if magnetic resonance imaging (MRI) and scalp electroencephalography (EEG) do not localize the seizure onset zone or are discordant. METHODS: In this multicenter, retrospective observational cohort study, we included consecutive patients with DRE who had undergone FDG-PET as part of their presurgical workup. We assessed the utility of FDG-PET, which was defined as contributing to the decision-making process to refer for resection or intracranial EEG (iEEG) or to conclude surgery was not feasible. RESULTS: We included 951 patients in this study; 479 had temporal lobe epilepsy (TLE), 219 extratemporal epilepsy (ETLE), and 253 epilepsy of uncertain lobar origin. FDG-PET showed a distinct hypometabolism in 62% and was concordant with ictal EEG in 74% in TLE and in 56% in ETLE (p < .001). FDG-PET was useful in presurgical decision-making in 396 patients (47%) and most beneficial in TLE compared to ETLE (58% vs. 44%, p = .001). Overall, FDG-PET contributed to recommending resection in 78 cases (20%) and iEEG in 187 cases (47%); in 131 patients (33%), FDG-PET resulted in a conclusion that resection was not feasible. In TLE, seizure-freedom 1 year after surgery did not differ significantly (p = .48) between patients with negative MRI and EEG-PET concordance (n = 30, 65%) and those with positive MRI and concordant EEG (n = 46, 68%). In ETLE, half of patients with negative MRI and EEG-PET concordance and three quarters with positive MRI and concordant EEG were seizure-free postsurgery (n = 5 vs. n = 6, p = .28). SIGNIFICANCE: This is the largest reported cohort of patients with DRE who received presurgical FDG-PET, showing that FDG-PET is a useful diagnostic tool. MRI-negative and MRI-positive cases with concordant FDG-PET results (with either EEG or MRI) had a comparable outcome after surgery. These findings confirm the significance of FDG-PET in presurgical epilepsy diagnostics.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia do Lobo Temporal , Epilepsia , Epilepsia Resistente a Medicamentos/cirurgia , Eletroencefalografia , Epilepsias Parciais/cirurgia , Epilepsia/diagnóstico por imagem , Epilepsia/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons/métodos , Estudos Retrospectivos , Convulsões
9.
Brain ; 144(2): 434-449, 2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33479777

RESUMO

Alzheimer's disease has a preclinical stage when cerebral amyloid-ß deposition occurs before symptoms emerge, and when amyloid-ß-targeted therapies may have maximum benefits. Existing amyloid-ß status measurement techniques, including amyloid PET and CSF testing, are difficult to deploy at scale, so blood biomarkers are increasingly considered for screening. We compared three different blood-based techniques-liquid chromatography-mass spectrometry measures of plasma amyloid-ß, and single molecule array (Simoa) measures of plasma amyloid-ß and phospho-tau181-to detect cortical 18F-florbetapir amyloid PET positivity (defined as a standardized uptake value ratio of >0.61 between a predefined cortical region of interest and eroded subcortical white matter) in dementia-free members of Insight 46, a substudy of the population-based British 1946 birth cohort. We used logistic regression models with blood biomarkers as predictors of amyloid PET status, with or without age, sex and APOE ε4 carrier status as covariates. We generated receiver operating characteristics curves and quantified areas under the curves to compare the concordance of the different blood tests with amyloid PET. We determined blood test cut-off points using Youden's index, then estimated numbers needed to screen to obtain 100 amyloid PET-positive individuals. Of the 502 individuals assessed, 441 dementia-free individuals with complete data were included; 82 (18.6%) were amyloid PET-positive. The area under the curve for amyloid PET status using a base model comprising age, sex and APOE ε4 carrier status was 0.695 (95% confidence interval: 0.628-0.762). The two best-performing Simoa plasma biomarkers were amyloid-ß42/40 (0.620; 0.548-0.691) and phospho-tau181 (0.707; 0.646-0.768), but neither outperformed the base model. Mass spectrometry plasma measures performed significantly better than any other measure (amyloid-ß1-42/1-40: 0.817; 0.770-0.864 and amyloid-ß composite: 0.820; 0.775-0.866). At a cut-off point of 0.095, mass spectrometry measures of amyloid-ß1-42/1-40 detected amyloid PET positivity with 86.6% sensitivity and 71.9% specificity. Without screening, to obtain 100 PET-positive individuals from a population with similar amyloid PET positivity prevalence to Insight 46, 543 PET scans would need to be performed. Screening using age, sex and APOE ε4 status would require 940 individuals, of whom 266 would proceed to scan. Using mass spectrometry amyloid-ß1-42/1-40 alone would reduce these numbers to 623 individuals and 243 individuals, respectively. Across a theoretical range of amyloid PET positivity prevalence of 10-50%, mass spectrometry measures of amyloid-ß1-42/1-40 would consistently reduce the numbers proceeding to scans, with greater cost savings demonstrated at lower prevalence.


Assuntos
Doença de Alzheimer/sangue , Doença de Alzheimer/diagnóstico , Peptídeos beta-Amiloides/sangue , Fragmentos de Peptídeos/sangue , Idoso , Doença de Alzheimer/metabolismo , Biomarcadores/sangue , Diagnóstico Precoce , Feminino , Testes Hematológicos/métodos , Humanos , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
10.
J Med Internet Res ; 24(8): e40384, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36040790

RESUMO

BACKGROUND: Electronic health records (EHRs) with large sample sizes and rich information offer great potential for dementia research, but current methods of phenotyping cognitive status are not scalable. OBJECTIVE: The aim of this study was to evaluate whether natural language processing (NLP)-powered semiautomated annotation can improve the speed and interrater reliability of chart reviews for phenotyping cognitive status. METHODS: In this diagnostic study, we developed and evaluated a semiautomated NLP-powered annotation tool (NAT) to facilitate phenotyping of cognitive status. Clinical experts adjudicated the cognitive status of 627 patients at Mass General Brigham (MGB) health care, using NAT or traditional chart reviews. Patient charts contained EHR data from two data sets: (1) records from January 1, 2017, to December 31, 2018, for 100 Medicare beneficiaries from the MGB Accountable Care Organization and (2) records from 2 years prior to COVID-19 diagnosis to the date of COVID-19 diagnosis for 527 MGB patients. All EHR data from the relevant period were extracted; diagnosis codes, medications, and laboratory test values were processed and summarized; clinical notes were processed through an NLP pipeline; and a web tool was developed to present an integrated view of all data. Cognitive status was rated as cognitively normal, cognitively impaired, or undetermined. Assessment time and interrater agreement of NAT compared to manual chart reviews for cognitive status phenotyping was evaluated. RESULTS: NAT adjudication provided higher interrater agreement (Cohen κ=0.89 vs κ=0.80) and significant speed up (time difference mean 1.4, SD 1.3 minutes; P<.001; ratio median 2.2, min-max 0.4-20) over manual chart reviews. There was moderate agreement with manual chart reviews (Cohen κ=0.67). In the cases that exhibited disagreement with manual chart reviews, NAT adjudication was able to produce assessments that had broader clinical consensus due to its integrated view of highlighted relevant information and semiautomated NLP features. CONCLUSIONS: NAT adjudication improves the speed and interrater reliability for phenotyping cognitive status compared to manual chart reviews. This study underscores the potential of an NLP-based clinically adjudicated method to build large-scale dementia research cohorts from EHRs.


Assuntos
COVID-19 , Demência , Idoso , Algoritmos , Teste para COVID-19 , Cognição , Demência/diagnóstico , Registros Eletrônicos de Saúde , Humanos , Medicare , Processamento de Linguagem Natural , Reprodutibilidade dos Testes , Estados Unidos
11.
Brain ; 143(3): 877-890, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203579

RESUMO

In theory the most powerful technique for functional localization in cognitive neuroscience, lesion-deficit mapping is in practice distorted by unmodelled network disconnections and strong 'parasitic' dependencies between collaterally damaged ischaemic areas. High-dimensional multivariate modelling can overcome these defects, but only at the cost of commonly impracticable data scales. Here we develop lesion-deficit mapping with metabolic lesions-discrete areas of hypometabolism typically seen on interictal 18F-fluorodeoxyglucose PET imaging in patients with focal epilepsy-that inherently capture disconnection effects, and whose structural dependence patterns are sufficiently benign to allow the derivation of robust functional anatomical maps with modest data. In this cross-sectional study of 159 patients with widely distributed focal cortical impairments, we derive lesion-deficit maps of a broad range of psychological subdomains underlying affect and cognition. We demonstrate the potential clinical utility of the approach in guiding therapeutic resection for focal epilepsy or other neurosurgical indications by applying high-dimensional modelling to predict out-of-sample verbal IQ and depression from cortical metabolism alone.


Assuntos
Encéfalo/metabolismo , Encéfalo/fisiologia , Disfunção Cognitiva/metabolismo , Epilepsias Parciais/metabolismo , Adulto , Estudos Transversais , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Adulto Jovem
12.
Eur J Nucl Med Mol Imaging ; 47(8): 1885-1912, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388612

RESUMO

PURPOSE: This joint practice guideline or procedure standard was developed collaboratively by the European Association of Nuclear Medicine (EANM) and the Society of Nuclear Medicine and Molecular Imaging (SNMMI). The goal of this guideline is to assist nuclear medicine practitioners in recommending, performing, interpreting, and reporting the results of dopaminergic imaging in parkinsonian syndromes. METHODS: Currently nuclear medicine investigations can assess both presynaptic and postsynaptic function of dopaminergic synapses. To date both EANM and SNMMI have published procedural guidelines for dopamine transporter imaging with single photon emission computed tomography (SPECT) (in 2009 and 2011, respectively). An EANM guideline for D2 SPECT imaging is also available (2009). Since the publication of these previous guidelines, new lines of evidence have been made available on semiquantification, harmonization, comparison with normal datasets, and longitudinal analyses of dopamine transporter imaging with SPECT. Similarly, details on acquisition protocols and simplified quantification methods are now available for dopamine transporter imaging with PET, including recently developed fluorinated tracers. Finally, [18F]fluorodopa PET is now used in some centers for the differential diagnosis of parkinsonism, although procedural guidelines aiming to define standard procedures for [18F]fluorodopa imaging in this setting are still lacking. CONCLUSION: All these emerging issues are addressed in the present procedural guidelines for dopaminergic imaging in parkinsonian syndromes.


Assuntos
Medicina Nuclear , Transtornos Parkinsonianos , Humanos , Imagem Molecular , Transtornos Parkinsonianos/diagnóstico por imagem , Cintilografia , Tomografia Computadorizada de Emissão de Fóton Único
13.
Ann Intern Med ; 168(6): 385-395, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29459986

RESUMO

Background: Synovitis is believed to play a role in producing symptoms in persons with hand osteoarthritis, but data on slow-acting anti-inflammatory treatments are sparse. Objective: To determine the effectiveness of hydroxychloroquine versus placebo as an analgesic treatment of hand osteoarthritis. Design: Randomized, double-blind, placebo-controlled clinical trial with 12-month follow-up. (ISRCTN registry number: ISRCTN91859104). Setting: 13 primary and secondary care centers in England. Participants: Of 316 patients screened, 248 participants (82% women; mean age, 62.7 years) with symptomatic (pain ≥4 on a 0- to 10-point visual analogue scale) and radiographic hand osteoarthritis were randomly assigned and 210 (84.7%) completed the 6-month primary end point. Intervention: Hydroxychloroquine (200 to 400 mg) or placebo (1:1) for 12 months with ongoing usual care. Measurements: The primary end point was average hand pain during the previous 2 weeks (on a 0- to 10-point numerical rating scale [NRS]) at 6 months. Secondary end points included self-reported pain and function, grip strength, quality of life, radiographic structural change, and adverse events. Baseline ultrasonography was done. Results: At 6 months, mean hand pain was 5.49 points in the placebo group and 5.66 points in the hydroxychloroquine group, with a treatment difference of -0.16 point (95% CI, -0.73 to 0.40 point) (P = 0.57). Results were robust to adjustments for adherence, missing data, and use of rescue medication. No significant treatment differences existed at 3, 6, or 12 months for any secondary outcomes. The percentage of participants with at least 1 joint with synovitis was 94% (134 of 143) on grayscale ultrasonography and 59% on power Doppler. Baseline structural damage or synovitis did not affect treatment response. Fifteen serious adverse events were reported (7 in the hydroxychloroquine group [3 defined as possibly related] and 8 in the placebo group). Limitation: Hydroxychloroquine dosage restrictions may have reduced efficacy. Conclusion: Hydroxychloroquine was no more effective than placebo for pain relief in patients with moderate to severe hand pain and radiographic osteoarthritis. Primary Funding Source: Arthritis Research UK.


Assuntos
Antirreumáticos/uso terapêutico , Mãos , Hidroxicloroquina/uso terapêutico , Osteoartrite/tratamento farmacológico , Método Duplo-Cego , Inglaterra , Feminino , Força da Mão , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Medição da Dor , Qualidade de Vida , Resultado do Tratamento
14.
Lancet ; 390(10103): 1664-1675, 2017 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-28781108

RESUMO

BACKGROUND: Exenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist, has neuroprotective effects in preclinical models of Parkinson's disease. We investigated whether these effects would be apparent in a clinical trial. METHODS: In this single-centre, randomised, double-blind, placebo-controlled trial, patients with moderate Parkinson's disease were randomly assigned (1:1) to receive subcutaneous injections of exenatide 2 mg or placebo once weekly for 48 weeks in addition to their regular medication, followed by a 12-week washout period. Eligible patients were aged 25-75 years, had idiopathic Parkinson's disease as measured by Queen Square Brain Bank criteria, were on dopaminergic treatment with wearing-off effects, and were at Hoehn and Yahr stage 2·5 or less when on treatment. Randomisation was by web-based randomisation with a two strata block design according to disease severity. Patients and investigators were masked to treatment allocation. The primary outcome was the adjusted difference in the Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor subscale (part 3) in the practically defined off-medication state at 60 weeks. All efficacy analyses were based on a modified intention-to-treat principle, which included all patients who completed any post-randomisation follow-up assessments. The study is registered at ClinicalTrials.gov (NCT01971242) and is completed. FINDINGS: Between June 18, 2014, and March 13, 2015, 62 patients were enrolled and randomly assigned, 32 to exenatide and 30 to placebo. Our primary analysis included 31 patients in the exenatide group and 29 patients in the placebo group. At 60 weeks, off-medication scores on part 3 of the MDS-UPDRS had improved by 1·0 points (95% CI -2·6 to 0·7) in the exenatide group and worsened by 2·1 points (-0·6 to 4·8) in the placebo group, an adjusted mean difference of -3·5 points (-6·7 to -0·3; p=0·0318). Injection site reactions and gastrointestinal symptoms were common adverse events in both groups. Six serious adverse events occurred in the exenatide group and two in the placebo group, although none in either group were judged to be related to the study interventions. INTERPRETATION: Exenatide had positive effects on practically defined off-medication motor scores in Parkinson's disease, which were sustained beyond the period of exposure. Whether exenatide affects the underlying disease pathophysiology or simply induces long-lasting symptomatic effects is uncertain. Exenatide represents a major new avenue for investigation in Parkinson's disease, and effects on everyday symptoms should be examined in longer-term trials. FUNDING: Michael J Fox Foundation for Parkinson's Research.


Assuntos
Doença de Parkinson/tratamento farmacológico , Peptídeos/administração & dosagem , Peçonhas/administração & dosagem , Adulto , Idoso , Método Duplo-Cego , Esquema de Medicação , Exenatida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/efeitos dos fármacos , Resultado do Tratamento
15.
Mov Disord ; 33(3): 478-482, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29380907

RESUMO

OBJECTIVE: The objective of this study was to examine whether prediagnostic features of Parkinson's disease (PD) were associated with changes in dopamine reuptake transporter-single-photon emission computed tomography and transcranial sonography. METHODS: Prediagnostic features of PD (risk estimates, University of Pennsylvania Smell Identification Test, Rapid Eye Movement Sleep Behavior Disorder Screening Questionnaire, and finger-tapping scores) were assessed in a large cohort of older U.K. residents. A total of 46 participants were included in analyses of prediagnostic features and MDS-UPDRS scores with the striatal binding ratio on dopamine reuptake transporter-single-photon emission computed tomography and nigral hyperechogenicity on transcranial sonography. RESULTS: The striatal binding ratio was associated with PD risk estimates (P = .040), University of Pennsylvania Smell Identification Test (P = .002), Rapid Eye Movement Sleep Behavior Disorder Screening Questionnaire scores (P = .024), tapping speed (P = .024), and MDS-UPDRS motor scores (P = .009). Remotely collected assessments explained 26% of variation in the striatal binding ratio. The inclusion of MDS-UPDRS motor scores did not explain additional variance. The size of the nigral echogenic area on transcranial sonography was associated with risk estimates (P < .001) and MDS-UPDRS scores (P = .03) only. CONCLUSIONS: The dopamine reuptake transporter-single-photon emission computed tomography results correlated with motor and nonmotor features of prediagnostic PD, supporting its potential use as a marker in the prodromal phase of PD. Transcranial sonography results also correlated with risk scores and motor signs. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Encéfalo/diagnóstico por imagem , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Ultrassonografia Doppler Transcraniana , Idoso , Encéfalo/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Transtornos do Olfato/diagnóstico por imagem , Doença de Parkinson/complicações , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Transtorno do Comportamento do Sono REM/etiologia
16.
Pathobiology ; 85(4): 261-265, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29788010

RESUMO

Mammary liposarcoma is among the rarest of breast tumours. Here we report the presentation, macroscopic, microscopic, and immunohistochemical features of an extremely rare case of metaplastic carcinoma with extensive pleomorphic liposarcomatous differentiation. A 47-year-old woman presented with bilateral grade III breast ptosis and a 3 × 4 cm mass in the lower outer quadrant of the left breast. Mammography and ultrasound confirmed a well-defined mass. A core biopsy performed was diagnosed as pleomorphic liposarcoma. Microscopically, this was a well-defined, lobulated tumour comprising solid sheets of large pleomorphic and spindle cells with bizarre forms, vacuolated cytoplasm, and ample mitoses. Atypical lipoblasts were easily identifiable. Due to the strong, though patchy, cytokeratin expression, the diagnosis of metaplastic carcinoma with pleomorphic liposarcomatous differentiation was made. Extensive sampling, careful search for a biphasic pattern, ductal carcinoma in situ, and/or epithelial differentiation, and a panel of broad-spectrum cytokeratins are essential to establish the diagnosis.


Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma/diagnóstico , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma/patologia , Carcinoma/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Lipossarcoma/diagnóstico , Lipossarcoma/patologia , Mastectomia Segmentar , Pessoa de Meia-Idade
17.
BMC Neurol ; 17(1): 75, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28420323

RESUMO

BACKGROUND: Increasing age is the biggest risk factor for dementia, of which Alzheimer's disease is the commonest cause. The pathological changes underpinning Alzheimer's disease are thought to develop at least a decade prior to the onset of symptoms. Molecular positron emission tomography and multi-modal magnetic resonance imaging allow key pathological processes underpinning cognitive impairment - including ß-amyloid depostion, vascular disease, network breakdown and atrophy - to be assessed repeatedly and non-invasively. This enables potential determinants of dementia to be delineated earlier, and therefore opens a pre-symptomatic window where intervention may prevent the onset of cognitive symptoms. METHODS/DESIGN: This paper outlines the clinical, cognitive and imaging protocol of "Insight 46", a neuroscience sub-study of the MRC National Survey of Health and Development. This is one of the oldest British birth cohort studies and has followed 5362 individuals since their birth in England, Scotland and Wales during one week in March 1946. These individuals have been tracked in 24 waves of data collection incorporating a wide range of health and functional measures, including repeat measures of cognitive function. Now aged 71 years, a small fraction have overt dementia, but estimates suggest that ~1/3 of individuals in this age group may be in the preclinical stages of Alzheimer's disease. Insight 46 is recruiting 500 study members selected at random from those who attended a clinical visit at 60-64 years and on whom relevant lifecourse data are available. We describe the sub-study design and protocol which involves a prospective two time-point (0, 24 month) data collection covering clinical, neuropsychological, ß-amyloid positron emission tomography and magnetic resonance imaging, biomarker and genetic information. Data collection started in 2015 (age 69) and aims to be completed in 2019 (age 73). DISCUSSION: Through the integration of data on the socioeconomic environment and on physical, psychological and cognitive function from 0 to 69 years, coupled with genetics, structural and molecular imaging, and intensive cognitive and neurological phenotyping, Insight 46 aims to identify lifetime factors which influence brain health and cognitive ageing, with particular focus on Alzheimer's disease and cerebrovascular disease. This will provide an evidence base for the rational design of disease-modifying trials.


Assuntos
Diagnóstico Precoce , Projetos de Pesquisa , Idoso , Doença de Alzheimer/diagnóstico , Biomarcadores/análise , Demência/diagnóstico , Inglaterra , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escócia
18.
Bioorg Med Chem ; 25(15): 3947-3963, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601508

RESUMO

We have applied simulated annealing of chemical potential (SACP) to a diverse set of ∼150 very small molecules to provide insights into new interactions in the binding pocket of human renin, a historically difficult target for which to find low molecular weight (MW) inhibitors with good bioavailability. In one of its many uses in drug discovery, SACP provides an efficient, thermodynamically principled method of ranking chemotype replacements for scaffold hopping and manipulating physicochemical characteristics for drug development. We introduce the use of Constrained Fragment Analysis (CFA) to construct and analyze ligands composed of linking those fragments with predicted high affinity. This technique addresses the issue of effectively linking fragments together and provides a predictive mechanism to rank order prospective inhibitors for synthesis. The application of these techniques to the identification of novel inhibitors of human renin is described. Synthesis of a limited set of designed compounds provided potent, low MW analogs (IC50s<100nM) with good oral bioavailability (F>20-58%).


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Renina/antagonistas & inibidores , Animais , Disponibilidade Biológica , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Humanos , Ratos , Relação Estrutura-Atividade , Termodinâmica
19.
Acta Paediatr ; 106(12): 1928-1933, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28833570

RESUMO

AIM: To describe the neural breathing pattern before and after extubation in newborn infants. METHODS: Prospective, observational study. In infants deemed ready for extubation, the diaphragm electrical activity (EAdi) was continuously recorded from 30 minute before to two hours after extubation. RESULTS: Total of 25 neonates underwent 29 extubations; 10 extubations resulted in re-intubation within 72 hours. Postextubation, there was an increase in peak EAdi (EAdi-max) and EAdi-delta (peak minus minimum EAdi) in both groups. The pre- to postextubation change in EAdi-max (8.9-11.1 µv) and EAdi-delta (6-8 µv) was less in the failure group in comparison with the change in EAdi-max (10.2-13.4 µv) and EAdi-delta (6.3-10.6 µv) in the success group, (p = 0.02 and 0.01, respectively). CONCLUSION: In our neonatal cohort, extubation failure was associated with a smaller increase in peak and delta EAdi after extubation. If confirmed, these findings indicate an important cause of extubation failure in preterm infants.


Assuntos
Extubação , Diafragma/fisiologia , Respiração , Feminino , Humanos , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Masculino , Estudos Prospectivos
20.
Eur J Nucl Med Mol Imaging ; 43(7): 1323-36, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26816194

RESUMO

PURPOSE: Quantitative estimates of dopamine transporter availability, determined with [(123)I]FP-CIT SPECT, depend on the SPECT equipment, including both hardware and (reconstruction) software, which limits their use in multicentre research and clinical routine. This study tested a dedicated reconstruction algorithm for its ability to reduce camera-specific intersubject variability in [(123)I]FP-CIT SPECT. The secondary aim was to evaluate binding in whole brain (excluding striatum) as a reference for quantitative analysis. METHODS: Of 73 healthy subjects from the European Normal Control Database of [(123)I]FP-CIT recruited at six centres, 70 aged between 20 and 82 years were included. SPECT images were reconstructed using the QSPECT software package which provides fully automated detection of the outer contour of the head, camera-specific correction for scatter and septal penetration by transmission-dependent convolution subtraction, iterative OSEM reconstruction including attenuation correction, and camera-specific "to kBq/ml" calibration. LINK and HERMES reconstruction were used for head-to-head comparison. The specific striatal [(123)I]FP-CIT binding ratio (SBR) was computed using the Southampton method with binding in the whole brain, occipital cortex or cerebellum as the reference. The correlation between SBR and age was used as the primary quality measure. RESULTS: The fraction of SBR variability explained by age was highest (1) with QSPECT, independently of the reference region, and (2) with whole brain as the reference, independently of the reconstruction algorithm. CONCLUSION: QSPECT reconstruction appears to be useful for reduction of camera-specific intersubject variability of [(123)I]FP-CIT SPECT in multisite and single-site multicamera settings. Whole brain excluding striatal binding as the reference provides more stable quantitative estimates than occipital or cerebellar binding.


Assuntos
Bases de Dados Factuais , Voluntários Saudáveis , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada de Emissão de Fóton Único/instrumentação , Tropanos/metabolismo , Fatores Etários , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Europa (Continente) , Humanos , Sensibilidade e Especificidade
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