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1.
Heliyon ; 10(9): e30030, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707442

RESUMO

Objective: To investigate the knowledge of diagnostic reference levels (DRLs), image quality, radiation dose and protocol parameters among Jordanian medical imaging professionals (MIPs) involved in PET/CT and CT scan procedures. Materials and methods: A questionnaire was designed and distributed to MIPs in Jordan. The survey comprised four sections: demographic data, MIP knowledge on dose/protocol parameters, image quality, and DRLs. Statistical analyses were performed utilizing Pearson's correlation, t-tests, ANOVA, and linear regression, with a significance level of 95 % and a p-value threshold of <0.05. Results: The study involved 147 participants. Most respondents were male (76.2 %), and most were aged 26-35 years (44.2 %). Approximately 51 % held a bachelor's degree, and the most common range of experience was 3-5 years (28.6 %). Participants showed a moderate level of knowledge regarding dose and protocol parameters, with a mean score of 61.8 %. The mean scores for knowledge of image quality and DRLs were 45.2 % and 44.8 %, respectively. The age group of the MIPs and the total experience were found to have a significant impact on the knowledge of the dose and protocol parameters, as well as the DRLs. Additionally, experience was found to have a significant influence on knowledge of the dose and protocol parameters. The study revealed a positive and significant effect of MIPs' knowledge of dose/protocol parameters and image quality on their knowledge of DRLs. Conclusions: This study indicates that professionals across five specialties who are engaged in PET/CT and CT imaging possess a moderate understanding of dosage and protocol parameters. However, there is a notable gap in knowledge regarding DRLs and image quality. To address this issue, it is recommended that MIPs actively engage in educational programs emphasizing exposure parameters and their impact on image quality. Additionally, access to comprehensive education and training programs will enable MIPs to grasp the complexities of DRLs and their implications, facilitating their implementation in clinical practice.

2.
J Radiol Prot ; 44(1)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38387102

RESUMO

This study aims to report the findings of Jordanian national diagnostic reference level (NDRL) survey for fluorodeoxyglucose (18F-FDG) and local diagnostic reference level (LDRL) of computed tomography (CT) used for attenuation correction and anatomical localisation (AC-AL); and AC and diagnostic CT (AC-DX) within the context of whole-body WB and half-body HB adult oncology PET/CT scanning. Two-structured questionnaires were prepared to gather the necessary information: dosimetry data, patient demographics, equipment specification, and acquisition protocols for identified18F-FDG PET/CT procedures. The NDRL and achievable dose were reported based on the 75th and 50th percentiles for18F-FDG administered activity (AA), respectively. The LDRL was reported based on the 50th percentile for (CTDIvol) and (DLP). Data from 562 patients from four Jordanian PET/CT centres were collected. The survey revealed that Jordanian NDRL for AA (303 MBq) was within the acceptable range compared to the published-peer NDRL data (240-590 MBq). However, the18F-FDG AA varied across the participated PET/CT centres. The reported LDRL CTDIvoland DLP of CT used for (AC-AL) was 4.3 mGy and 459.3 mGy.cm for HB CT scan range, and 4.1 mGy and 659.9 mGy.cm for WB CT scans. The reported LDRL for CTDIvoland DLP for HB CT was higher when compared with the United Kingdom (3.2 mGy and 310 mGy.cm). Concurrently, in the context of WB CT, the reported values (i.e. CTDIvol and DLP) were also higher than both Kuwait (3.6 mGy and 659 mGy.cm) and Slovenia (3.6 mGy and 676 mGy.cm). The reported HB CT(AC-DX) was higher than Nordic, New Zealand and Swiss NDRLs and for WB (AC-DX) CT it was higher than Swiss NDRLs. This study reported the first Jordanian NDRL for18F-FDG and LDRL for HB and WB CT associated with18F-FDG PET/CT scans. This data is useful for Jordanian PET/CT centres to compare their LDRL to the suggested DRLs and utilise it in the process of optimising CT radiation doses.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adulto , Humanos , Níveis de Referência de Diagnóstico , Doses de Radiação , Jordânia , Valores de Referência , Tomografia Computadorizada por Raios X
3.
Nucl Med Commun ; 44(11): 937-943, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37615527

RESUMO

PET-computed tomography (PET/CT) is a hybrid imaging technique that combines anatomical and functional information; to investigate primary cancers, stage tumours, and track treatment response in paediatric oncology patients. However, there is debate in the literature about whether PET/CT could increase the risk of cancer in children, as the machine is utilizing two types of radiation, and paediatric patients have faster cell division and longer life expectancy. Therefore, it is essential to minimize radiation exposure by justifying and optimizing PET/CT examinations and ensure an acceptable image quality. Establishing diagnostic reference levels (DRLs) is a crucial quantitative indicator and effective tool to optimize paediatric imaging procedures. This review aimed to distinguish and acknowledge variations among published DRLs for paediatric patients in PET/CT procedures. A search of relevant articles was conducted using databases, that is, Embase, Scopus, Web of Science, and Medline, using the keywords: PET-computed tomography, computed tomography, PET, radiopharmaceutical, DRL, and their synonyms. Only English and full-text articles were included, with no limitations on the publication year. After the screening, four articles were selected, and the review reveals different DRL approaches for paediatric patients undergoing PET/CT, with primary variations observed in patient selection criteria, reporting of radiation dose values, and PET/CT equipment. The study suggests that future DRL methods for paediatric patients should prioritize data collection in accordance with international guidelines to better understand PET/CT dose discrepancies while also striving to optimize radiation doses without compromising the quality of PET/CT images.


Assuntos
Níveis de Referência de Diagnóstico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Criança , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Doses de Radiação , Tomografia Computadorizada por Raios X , Compostos Radiofarmacêuticos , Valores de Referência
4.
Acad Radiol ; 29 Suppl 3: S114-S121, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-29054676

RESUMO

RATIONALE AND OBJECTIVE: This study is a dedicated 2D-shear wave elastography (2D-SWE) review aimed at systematically eliciting up-to-date evidence of its clinical value in differential diagnosis of benign and malignant thyroid nodules. METHODS: PubMed, Web of Science, and Scopus databases were searched for studies assessing the diagnostic value of 2D-SWE for thyroid malignancy risk stratification published until December 2016. The retrieved titles and abstracts were screened and evaluated according to the predefined inclusion and exclusion criteria. Methodological quality of the studies was assessed using the Quality Assessment of Studies of Diagnostic Accuracy included in Systematic Review 2 (QUADAS-2) tool. Extracted 2D-SWE diagnostic performance data were meta-analyzed to assess the summary sensitivity, specificity, and area under the receiver operating characteristic curve. RESULTS: After stepwise review, 14 studies in which 2D-SWE was used to evaluate 2851 thyroid nodules (1092 malignant, 1759 benign) from 2139 patients were selected for the current study. Study quality on QUADAS-2 assessment was moderate to high. The summary sensitivity, specificity and area under the receiver operating characteristic curve of 2D-SWE for differential diagnosis of benign and malignant thyroid nodules were 0.66 (95% confidence interval [CI]: 0.64-0.69), 0.78 (CI: 0.76-0.80), and 0.851 (Q* = 0.85), respectively. The pooled diagnostic odds ratio, negative likelihood ratio, and positive likelihood ratio were 12.73 (CI: 8.80-18.43), 0.31 (CI: 0.22-0.44), and 3.87 (CI: 2.83-5.29), respectively. CONCLUSION: Diagnostic performance of quantitative 2D-SWE for malignancy risk stratification of thyroid nodules is suboptimal with mediocre sensitivity and specificity, contrary to earlier reports of excellence.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/patologia
5.
PLoS One ; 16(9): e0252883, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34547018

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a major neurocognitive disorder identified by memory loss and a significant cognitive decline based on previous level of performance in one or more cognitive domains that interferes in the independence of everyday activities. The accuracy of imaging helps to identify the neuropathological features that differentiate AD from its common precursor, mild cognitive impairment (MCI). Identification of early signs will aid in risk stratification of disease and ensures proper management is instituted to reduce the morbidity and mortality associated with AD. Magnetic resonance imaging (MRI) using structural MRI (sMRI), functional MRI (fMRI), diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (1H-MRS) performed alone is inadequate. Thus, the combination of multiparametric MRI is proposed to increase the accuracy of diagnosing MCI and AD when compared to elderly healthy controls. METHODS: This protocol describes a non-interventional case control study. The AD and MCI patients and the healthy elderly controls will undergo multi-parametric MRI. The protocol consists of sMRI, fMRI, DTI, and single-voxel proton MRS sequences. An eco-planar imaging (EPI) will be used to perform resting-state fMRI sequence. The structural images will be analysed using Computational Anatomy Toolbox-12, functional images will be analysed using Statistical Parametric Mapping-12, DPABI (Data Processing & Analysis for Brain Imaging), and Conn software, while DTI and 1H-MRS will be analysed using the FSL (FMRIB's Software Library) and Tarquin respectively. Correlation of the MRI results and the data acquired from the APOE genotyping, neuropsychological evaluations (i.e. Montreal Cognitive Assessment [MoCA], and Mini-Mental State Examination [MMSE] scores) will be performed. The imaging results will also be correlated with the sociodemographic factors. The diagnosis of AD and MCI will be standardized and based on the DSM-5 criteria and the neuropsychological scores. DISCUSSION: The combination of sMRI, fMRI, DTI, and MRS sequences can provide information on the anatomical and functional changes in the brain such as regional grey matter volume atrophy, impaired functional connectivity among brain regions, and decreased metabolite levels specifically at the posterior cingulate cortex/precuneus. The combination of multiparametric MRI sequences can be used to stratify the management of MCI and AD patients. Accurate imaging can decide on the frequency of follow-up at memory clinics and select classifiers for machine learning that may aid in the disease identification and prognostication. Reliable and consistent quantification, using standardised protocols, are crucial to establish an optimal diagnostic capability in the early detection of Alzheimer's disease.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Malásia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
6.
J Alzheimers Dis ; 82(2): 673-687, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34092633

RESUMO

BACKGROUND: Cognitive frailty (CF) is identified as one of the main precursors of dementia. Multidomain intervention has been found to delay or prevent the onset of CF. OBJECTIVE: The aim of our present study is to determine the effectiveness of a comprehensive, multidomain intervention on CF; to evaluate its cost effectiveness and the factors influencing adherence toward this intensive intervention. METHODS: A total of 1,000 community dwelling older adults, aged 60 years and above will be screened for CF. This randomized controlled trial involves recruitment of 330 older adults with CF from urban, semi-urban, and rural areas in Malaysia. Multidomain intervention comprised of physical, nutritional, cognitive, and psychosocial aspects will be provided to participants in the experimental group (n = 165). The control group (n = 165) will continue their usual care with their physician. Primary outcomes include CF status, physical function, psychosocial and nutritional status as well as cognitive performance. Vascular health and gut microbiome will be assessed using blood and stool samples. A 24-month intensive intervention will be prescribed to the participants and its sustainability will be assessed for the following 12 months. The effective intervention strategies will be integrated as a personalized telerehabilitation package for the reversal of CF for future use. RESULTS: The multidomain intervention developed from this trial is expected to be cost effective compared to usual care as well as able is to reverse CF. CONCLUSION: This project will be part of the World-Wide FINGERS (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability) Network, of which common identifiable data will be shared and harmonized among the consortia.


Assuntos
Cognição/fisiologia , Disfunção Cognitiva , Dieta Saudável/métodos , Idoso Fragilizado/psicologia , Desempenho Físico Funcional , Serviços Preventivos de Saúde , Intervenção Psicossocial/métodos , Idoso , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/psicologia , Análise Custo-Benefício , Feminino , Humanos , Vida Independente , Masculino , Programas de Rastreamento/métodos , Serviços Preventivos de Saúde/economia , Serviços Preventivos de Saúde/métodos , Avaliação de Programas e Projetos de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Telerreabilitação/métodos
7.
J Magn Reson Imaging ; 54(6): 1804-1818, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34080265

RESUMO

BACKGROUND: Cosmos caudatus (CC) is traditional Asian vegetable, commonly consumed among the Southeast Asian population. It has been reported to be high in flavonoids and might potentially improve brain activity among older adults with mild cognitive impairment (MCI). The effect of CC in brain activation improvement using neuroimaging is yet to be discovered. PURPOSE: To investigate the effects of CC supplement on brain activity using functional magnetic resonance imaging (fMRI) among older adults with MCI. STUDY TYPE: Prospective, randomized, double-blind, placebo-controlled trial. POPULATION/SUBJECTS: Twenty older adults with mild cognitive impairment (60-75 years old), 14 of them (70%) were female subjects. FIELD STRENGTH/SEQUENCE: A 3.0-T, T1-weighted anatomical images, T2*-weighted imaging data, A single shot, gradient echo-echo planar imaging (EPI) sequence. ASSESSMENT: All subjects were asked to consume two 500 mg capsules of either CC supplement or placebo (maltodextrin) daily for 12 weeks. Cognitive function was measured using validated neuropsychological tests (i.e. Mini-mental State Examination and Digit Span) and task-based fMRI (N-back and Stroop Color Word Test) at baseline and 12th week. Brodmann's area 9, 46 and anterior cingulate cortex were selected as the regions of interest to define dorsolateral prefrontal cortex (DLPFC) in fMRI analysis. STATISTICAL TESTS: Normality test was performed with the Shapiro-Wilk test. Two-way repeated ANOVA determined the intervention effects of the CC supplementation on brain activity after adjustments for covariates. Significance level at P < 0.05 for independent-t test and Chi square test; adjusted P < 0.0042 for two-way repeated ANOVA after Bonferroni correction. RESULTS: Findings showed significant improvements in digit span (partial η2  = 0.559), increment in right DLPFC activation while performing 1-back task (partial η2  = 0.586) and left DLPFC activation while performing Stroop Color Word Test (SCWT) (congruent) task (partial η2  = 0.432) at 12th week of CC supplementation. CONCLUSION: CC supplementation might have the ability to improve DLPFC activation, potentially leading to improved working memory among older adults with MCI after 12 weeks of administration. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 4.


Assuntos
Disfunção Cognitiva , Córtex Pré-Frontal Dorsolateral , Idoso , Cognição , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/tratamento farmacológico , Suplementos Nutricionais , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem , Estudos Prospectivos
8.
Hum Brain Mapp ; 42(9): 2941-2968, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33942449

RESUMO

Resting-state fMRI (rs-fMRI) detects functional connectivity (FC) abnormalities that occur in the brains of patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). FC of the default mode network (DMN) is commonly impaired in AD and MCI. We conducted a systematic review aimed at determining the diagnostic power of rs-fMRI to identify FC abnormalities in the DMN of patients with AD or MCI compared with healthy controls (HCs) using machine learning (ML) methods. Multimodal support vector machine (SVM) algorithm was the commonest form of ML method utilized. Multiple kernel approach can be utilized to aid in the classification by incorporating various discriminating features, such as FC graphs based on "nodes" and "edges" together with structural MRI-based regional cortical thickness and gray matter volume. Other multimodal features include neuropsychiatric testing scores, DTI features, and regional cerebral blood flow. Among AD patients, the posterior cingulate cortex (PCC)/Precuneus was noted to be a highly affected hub of the DMN that demonstrated overall reduced FC. Whereas reduced DMN FC between the PCC and anterior cingulate cortex (ACC) was observed in MCI patients. Evidence indicates that the nodes of the DMN can offer moderate to high diagnostic power to distinguish AD and MCI patients. Nevertheless, various concerns over the homogeneity of data based on patient selection, scanner effects, and the variable usage of classifiers and algorithms pose a challenge for ML-based image interpretation of rs-fMRI datasets to become a mainstream option for diagnosing AD and predicting the conversion of HC/MCI to AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Conectoma/normas , Imageamento por Ressonância Magnética/normas , Humanos , Aprendizado de Máquina , Valor Preditivo dos Testes
9.
PLoS One ; 16(2): e0245579, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33630876

RESUMO

Achieving biologically interpretable neural-biomarkers and features from neuroimaging datasets is a challenging task in an MRI-based dyslexia study. This challenge becomes more pronounced when the needed MRI datasets are collected from multiple heterogeneous sources with inconsistent scanner settings. This study presents a method of improving the biological interpretation of dyslexia's neural-biomarkers from MRI datasets sourced from publicly available open databases. The proposed system utilized a modified histogram normalization (MHN) method to improve dyslexia neural-biomarker interpretations by mapping the pixels' intensities of low-quality input neuroimages to range between the low-intensity region of interest (ROIlow) and high-intensity region of interest (ROIhigh) of the high-quality image. This was achieved after initial image smoothing using the Gaussian filter method with an isotropic kernel of size 4mm. The performance of the proposed smoothing and normalization methods was evaluated based on three image post-processing experiments: ROI segmentation, gray matter (GM) tissues volume estimations, and deep learning (DL) classifications using Computational Anatomy Toolbox (CAT12) and pre-trained models in a MATLAB working environment. The three experiments were preceded by some pre-processing tasks such as image resizing, labelling, patching, and non-rigid registration. Our results showed that the best smoothing was achieved at a scale value, σ = 1.25 with a 0.9% increment in the peak-signal-to-noise ratio (PSNR). Results from the three image post-processing experiments confirmed the efficacy of the proposed methods. Evidence emanating from our analysis showed that using the proposed MHN and Gaussian smoothing methods can improve comparability of image features and neural-biomarkers of dyslexia with a statistically significantly high disc similarity coefficient (DSC) index, low mean square error (MSE), and improved tissue volume estimations. After 10 repeated 10-fold cross-validation, the highest accuracy achieved by DL models is 94.7% at a 95% confidence interval (CI) level. Finally, our finding confirmed that the proposed MHN method significantly outperformed the normalization method of the state-of-the-art histogram matching.


Assuntos
Aprendizado Profundo , Dislexia/classificação , Dislexia/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Biomarcadores , Bases de Dados Factuais , Humanos , Distribuição Normal , Razão Sinal-Ruído
10.
Nutrients ; 13(2)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572715

RESUMO

Cosmos caudatus (CC) contains high flavonoids and might be beneficial in neuroprotection. It has the potential to prevent neurodegenerative diseases. Therefore, we aimed to investigate the effects of 12 weeks of Cosmos caudatus supplement on cognitive function, mood status, blood biochemical profiles and biomarkers among older adults with mild cognitive impairment (MCI) through a double-blind, placebo-controlled trial. The subjects were randomized into CC supplement (n = 24) and placebo group (n = 24). Each of them consumed one capsule of CC supplement (250 mg of CC/capsule) or placebo (500 mg maltodextrin/capsule) twice daily for 12 weeks. Cognitive function and mood status were assessed at baseline, 6th week, and 12th week using validated neuropsychological tests. Blood biochemical profiles and biomarkers were measured at baseline and 12th week. Two-way mixed analysis of variance (ANOVA) analysis showed significant improvements in mini mental state examination (MMSE) (partial η2 = 0.150, p = 0.049), tension (partial η2 = 0.191, p = 0.018), total mood disturbance (partial η2 = 0.171, p = 0.028) and malondialdehyde (MDA) (partial η2 = 0.097, p = 0.047) following CC supplementation. In conclusion, 12 weeks CC supplementation potentially improved global cognition, tension, total mood disturbance, and oxidative stress among older adults with MCI. Larger sample size and longer period of intervention with incorporation of metabolomic approach should be conducted to further investigate the underlying mechanism of CC supplementation in neuroprotection.


Assuntos
Asteraceae , Disfunção Cognitiva/terapia , Suplementos Nutricionais , Flavonoides/administração & dosagem , Extratos Vegetais/administração & dosagem , Afeto/efeitos dos fármacos , Idoso , Análise de Variância , Cognição/efeitos dos fármacos , Método Duplo-Cego , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resultado do Tratamento
11.
Front Hum Neurosci ; 15: 765451, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35046782

RESUMO

Working memory is developed in one region of the brain called the dorsolateral prefrontal cortex (DLPFC). The dysfunction of this region leads to synaptic neuroplasticity impairment. It has been reported that several biochemical parameters and anthropometric measurements play a vital role in cognition and brain health. This study aimed to investigate the relationships between cognitive function, serum biochemical profile, and anthropometric measurements using DLPFC activation. A cross-sectional study was conducted among 35 older adults (≥60 years) who experienced mild cognitive impairment (MCI). For this purpose, we distributed a comprehensive interview-based questionnaire for collecting sociodemographic information from the participants and conducting cognitive tests. Anthropometric values were measured, and fasting blood specimens were collected. We investigated their brain activation using the task-based functional MRI (fMRI; N-back), specifically in the DLPFC region. Positive relationships were observed between brain-derived neurotrophic factor (BDNF) (ß = 0.494, p < 0.01) and Mini-Mental State Examination (MMSE) (ß = 0.698, p < 0.01); however, negative relationships were observed between serum triglyceride (ß = -0.402, p < 0.05) and serum malondialdehyde (MDA) (ß = -0.326, p < 0.05) with right DLPFC activation (R 2 = 0.512) while the participants performed 1-back task after adjustments for age, gender, and years of education. In conclusion, higher serum triglycerides, higher oxidative stress, and lower neurotrophic factor were associated with lower right DLPFC activation among older adults with MCI. A further investigation needs to be carried out to understand the causal-effect mechanisms of the significant parameters and the DLPFC activation so that better intervention strategies can be developed for reducing the risk of irreversible neurodegenerative diseases among older adults with MCI.

12.
Acad Radiol ; 28(10): 1447-1463, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651050

RESUMO

BACKGROUND: There is compelling evidence that neurochemical changes measured by proton magnetic resonance spectroscopy (1H-MRS) occur at different phases of Alzheimer's disease (AD). However, the extent to which these neurochemical changes are associated with validated AD biomarkers and/or apolipoprotein (APOE) ε4 is yet to be established. OBJECTIVE: This systematic review analyzed the available evidence on (1) neurochemical changes; and (2) the relations between brain metabolite and validated cerebrospinal fluid biomarkers, and/or APOE in AD. METHODS: PubMed, Cochrane, Scopus, and gray literature were systematically screened for studies deemed fit for the purpose of the current systematic review. RESULTS: Twenty four articles met the inclusion criteria. Decreased levels of N-acetyl aspartate (NAA), NAA/(creatine) Cr, and NAA/(myo-inositol) ml, and increased ml, ml/Cr, Cho (choline)/Cr, and ml/NAA were found in the posterior cingulate cortex/precuneus. Increased ml is associated with increased tau levels, reduced NAA/Cr is associated with increased tau. ml/Cr is negatively correlated with Aß42, and ml/Cr is positively correlated with t-tau. NAA and glutathione levels are reduced in APOE ε4 carriers. APOE ε4 exerts no modulatory effect on NAA/Cr. There is interaction between APOE ε4, Aß42, and ml/Cr. CONCLUSION: NAA, ml, NAA/Cr, NAA/ml and ml/Cr may be potentially useful biomarkers that may highlight functional changes in the clinical stages of AD. The combinations of ml and tau, NAA/Cr and Aß42, and NAA/Cr and tau may support the diagnostic process of differentiating MCI/AD from healthy individuals. Large, longitudinal studies are required to clarify the effect of APOE ε4 on brain metabolites.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/diagnóstico por imagem , Apolipoproteínas , Encéfalo/diagnóstico por imagem , Humanos , Espectroscopia de Prótons por Ressonância Magnética
13.
BMC Complement Med Ther ; 20(1): 315, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33076878

RESUMO

BACKGROUND: Persicaria minor extract exhibits antioxidant and anti-inflammatory properties and has potential effects on cognitive function and mood. However, the effects of P.minor on brain activation and biomarkers have not been studied among older adults. This multicentre, randomized, double-blinded, placebo-controlled study aimed to investigate the effect of 6 months P.minor extract supplement (Biokesum®) on cognition, mood, biomarkers, and brain activation among older adults with Mild Cognitive Impairment (MCI). METHOD: A total of 36 Malaysian community-dwelling older adults with MCI (60-75-year-old) were randomized into Biokesum® (n = 18) and placebo group (n = 18). Each subject consumed one capsule of Biokesum® (250 mg/capsule) or placebo (maltodextrin, 280 mg/capsule) twice daily for 6 months. Cognitive function and mood were assessed at baseline, 3rd, and 6th-month using neuropsychological tests (MMSE, Digit Span, RAVLT, Digit Symbol, and Visual Reproduction) and Profile of Mood State (POMS) questionnaire. Blood lipid profile, fasting blood glucose, and biomarkers (MDA, LPO, COX-2, iNOS, and BDNF) were measured at baseline and 6th month. By the end of the intervention, there were 30 compliers (Biokesum®: N = 15; Placebo: N = 15) and 6 dropouts. For brain activation assessment, 15 subsamples (Biokesum®: N = 8; Placebo: N = 7) completed N-back and Stroop tasks during fMRI scanning at baseline and 6th month. The dorsolateral prefrontal cortex (Brodmann's area 9 and 46) was identified as a region of interest (ROI) for brain activation analysis using SPM software. RESULTS: Two-way mixed ANOVA analysis showed significant improvements in Visual Reproduction II (p = 0.012, partial η2 = 0.470), tension (p = 0.042, partial η2 = 0.147), anger (p = 0.010, partial η2 = 0.207), confusion (p = 0.041, partial η2 = 0.148), total negative subscales (p = 0.043, partial η2 = 0.145), BDNF (p = 0.020, partial η2 = 0.179) and triglyceride (p = 0.029, partial η2 = 0.237) following 6 months of Biokesum® supplementation. Preliminary finding also demonstrated significant improvement at 0-back task-induced right DLPFC activation (p = 0.028, partial η2 = 0.652) among subsamples in Biokesum® group. No adverse events were reported at the end of the study. CONCLUSION: Six months Biokesum® supplementation potentially improved visual memory, negative mood, BDNF, and triglyceride levels among older adults with MCI. Significant findings on brain activation at the right DPLFC must be considered as preliminary. TRIAL REGISTRATION: Retrospectively registered on 30th August 2019 [ ISRC TN12417552 ].


Assuntos
Afeto/efeitos dos fármacos , Disfunção Cognitiva/tratamento farmacológico , Suplementos Nutricionais , Extratos Vegetais/uso terapêutico , Idoso , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos , Teste de Stroop
14.
Exp Brain Res ; 238(4): 945-956, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32179941

RESUMO

The present study examined the impact of white noise on word recall performance and brain activity in 40 healthy adolescents, split in two groups (normal and low) depending on their auditory working memory capacity (AWMC). Using functional magnetic resonance imaging, participants performed a backward recall task under four different signal-to-noise ratio (SNR) conditions: 15, 10, 5, and 0-dB SNR. Behaviorally, normal AWMC individuals scored significantly higher than low AWMC individuals across noise levels. Whole-brain analyses showed brain activation not to be statistically different between groups across noise levels. In the normal group, a significant positive relationship was found between performance and number of activated voxels in the right superior frontal gyrus. In the low group, significant positive correlations were found between performance and number of activated voxels in left superior frontal gyrus, left inferior frontal gyrus, and left anterior cingulate cortex. These findings suggest that the strategic structure involved in the enhancement of AWM performance may differ in normal and low AWMC individuals.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Mapeamento Encefálico , Giro do Cíngulo/fisiologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Córtex Pré-Frontal/fisiologia , Adolescente , Feminino , Giro do Cíngulo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Ruído , Córtex Pré-Frontal/diagnóstico por imagem
15.
J Magn Reson Imaging ; 51(4): 1142-1153, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31386268

RESUMO

BACKGROUND: Working memory and cognitive flexibility are supported by the dorsolateral prefrontal cortex (DLPFC). Aging adults from low-income households are individuals with a high risk of cognitive decline who incorporate ulam in their daily diet. PURPOSE: To examine relationship between ulam consumption and the working memory and cognitive flexibility among aging adults from low-income households who are more susceptible to cognitive decline. STUDY TYPE: Cross-sectional. POPULATION/SUBJECTS: Thirty-two aging adults (45-75 years old). FIELD STRENGTH/SEQUENCE: Task-based fMRI, 3.0T, T1 -weighted anatomical images, T2 *-weighted imaging data. ASSESSMENT: The dietary and ulam consumption were assessed using the respective validated Dietary History and semiquantitative Food Frequency questionnaires. Working memory and cognitive flexibility were evaluated by using neuropsychological batteries (ie, mini-mental state examination [MMSE], Digit Span, and Rey auditory verbal learning test [RAVLT]) and task-based fMRI (N-back and Stroop Color Word Test [SCWT]). Brodmann's areas 9 and 46 were the regions of interest (ROIs) of DLPFC activation. STATISTICAL TESTS: Multiple linear regression used to understand the relationship between ulam consumption and the working memory and cognitive flexibility, while analysis of covariance (ANCOVA) was used to compare the difference of working memory and cognitive flexibility among four percentiles of ulam consumption, after age, gender, and education years adjustments. Significance was decided by two-sided, P < 0.0042 and P < 0.05. RESULTS: The multiple linear regression revealed that ulam consumption was positively associated with the Digit Span (R2 = 0.51, ß = 0.702, P < 0.001), right DLPFC activation (1-back) (R2 = 0.34, ß = 0.591, P = 0.001), left DLPFC activation (SCWT-1) (R2 = 0.33, ß = 0.553, P = 0.002), and left DLPFC activation (SCWT-2) (R2 = 0.34, ß = 0.497, P = 0.004). The ulam consumption at the 75th and 100th percentile from the ANCOVA analysis had shown a better working memory and cognitive flexibility as compared with those of the 25th and 50th percentiles (P < 0.05). DATA CONCLUSION: This study found that high ulam consumption was related to a high intensity of brain activation in DLPFC; however, the elucidation of the neuroprotective properties of ulam have yet to be established from clinical trial studies. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:1142-1153.


Assuntos
Imageamento por Ressonância Magnética , Verduras , Adulto , Idoso , Envelhecimento , Encéfalo/diagnóstico por imagem , Estudos Transversais , Humanos , Memória de Curto Prazo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Córtex Pré-Frontal
16.
J Magn Reson Imaging ; 51(6): 1821-1828, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31794119

RESUMO

BACKGROUND: The auditory and prefrontal cortex supports auditory working memory processing. Many neuroimaging studies have shown hemispheric lateralization of auditory working memory brain regions in the presence of background noise, but few studies have focused on the lateralization of these regions during stochastic resonance. PURPOSE: To investigate the effects of stochastic resonance on lateralization of auditory working memory regions, and also to examine the brain-behavior relationship during stochastic resonance. STUDY TYPE: Cross-sectional. POPULATION/SUBJECTS: Forty healthy young adults (18-24 years old). FIELD STRENGTH/SEQUENCE: 3.0T, T1 , and T2 *-weighted imaging. ASSESSMENT: The auditory working memory performance was assessed using a backward recall task. Functional magnetic resonance imaging (fMRI) was used to measure brain activity during task performance. Functional MRI data were analyzed using SPM12 and WFU PickAtlas. STATISTICAL TESTS: One-way independent analyses of variance (ANOVA) were conducted on the behavioral and functional data to examine the main effect of noise level on performance (P < 0.01) and brain activity (P < 0.0042). Hemispheric lateralization was determined by calculating the laterality index. A paired samples t-test was performed to compare brain activity between hemispheres (P < 0.05). Pearson's correlation analysis and simple linear regression (P < 0.0042) were used to examine the relationship between brain activity and behavioral performance. RESULTS: Performance was significantly enhanced during the 50 and 55 dB sound pressure level (SPL) conditions via the stochastic resonance mechanism [F(1,195) = 49.17, P < 0.001]. Activity of the right superior frontal gyrus in the 55 dB SPL condition was significantly positively correlated with performance (R2 = 0.681, P < 0.001). DATA CONCLUSION: Our findings demonstrate changes in the lateralization of auditory working memory regions during stochastic resonance and suggest that the right superior frontal gyrus may be a strategic structure involved in the enhancement of auditory working memory performance. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2020;51:1821-1828.


Assuntos
Mapeamento Encefálico , Imageamento por Ressonância Magnética , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Estudos Transversais , Lateralidade Funcional , Humanos , Memória de Curto Prazo , Adulto Jovem
17.
Heliyon ; 5(9): e02444, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687551

RESUMO

Research suggests that white noise may facilitate auditory working memory performance via stochastic resonance. Stochastic resonance is quantified by plotting cognitive performance as a function of noise intensity. The plot would appear as an inverted U-curve, that is, a moderate noise is beneficial for performance whereas too low and too much noise attenuates performance. However, knowledge about the optimal signal-to-noise ratio (SNR) needed for stochastic resonance to occur in the brain, particularly in the neural network of auditory working memory, is limited and demand further investigation. In the present study, we extended previous works on the impact of white noise on auditory working memory performance by including multiple background noise levels to map out the inverted U-curve for the stochastic resonance. Using functional magnetic resonance imaging (fMRI), twenty healthy young adults performed a word-based backward recall span task under four signal-to-noise ratio conditions: 15, 10, 5, and 0-dB SNR. Group results show significant behavioral improvement and increased activation in frontal cortices, primary auditory cortices, and anterior cingulate cortex in all noise conditions, except at 0-dB SNR, which decreases activation and performance. When plotted as a function of signal-to-noise ratio, behavioral and fMRI data exhibited a noise-benefit inverted U-shaped curve. Additionally, a significant positive correlation was found between the activity of the right superior frontal gyrus (SFG) and performance in 5-dB SNR. The predicted phenomenon of SR on auditory working memory performance is confirmed. Findings from this study suggest that the optimal signal-to-noise ratio to enhance auditory working memory performance is within 10 to 5-dB SNR and that the right SFG may be a strategic structure involved in enhancement of auditory working memory performance.

18.
Asian Pac J Cancer Prev ; 20(5): 1427-1432, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31127903

RESUMO

Objective: This study aims to investigate the public pattern in seeking breast cancer screening information in Malaysia using Google Trends. Methods: The Google Trends database was evaluated for the relative Internet search popularity of breast cancer and screening-related search terms from 2007 to 2018. Results: Result showed downward trends in breast cancer search, whereas mammogram and tomosynthesis search fluctuated consistently. A significant increment was found during Pink October month. Breast cancer search term achieved the highest popularity in the east coast of Malaysia with [x2 (5, N=661) = 110.93, P<0.05], whereas mammogram attained the highest search volume in central Malaysia [x2 (4, N=67) = 18.90, P<0.05]. The cross-correlation for breast cancer was moderate among northern Malaysia, Sabah, and Sarawak (0.3 ≤ rs ≤ 0.7). Conclusion: Public interest trend in breast cancer screening is strongly correlated with the breast cancer awareness campaign, Pink October. Breast cancer screening should be promoted in the rural areas in Malaysia.


Assuntos
Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/estatística & dados numéricos , Comportamento de Busca de Informação , Internet/estatística & dados numéricos , Mamografia/estatística & dados numéricos , Ferramenta de Busca/tendências , Neoplasias da Mama/psicologia , Detecção Precoce de Câncer/psicologia , Feminino , Humanos , Malásia , Prognóstico
19.
Clin Interv Aging ; 14: 43-51, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30613138

RESUMO

BACKGROUND: Dorsolateral prefrontal cortex (DLPFC) is a key node in the cognitive control network that supports working memory. DLPFC dysfunction is related to cognitive impairment. It has been suggested that dietary components and high-density lipoprotein cholesterol (HDL-C) play a vital role in brain health and cognitive function. PURPOSE: This study aimed to investigate the relationships between dietary nutrient intake and lipid levels with functional MRI (fMRI) brain activation in DLPFC among older adults with mild cognitive impairment. PARTICIPANTS AND METHODS: A total of 15 community-dwelling older adults with mild cognitive impairment, aged ≥60 years, participated in this cross-sectional study at selected senior citizen clubs in Klang Valley, Malaysia. The 7-day recall Diet History Questionnaire was used to assess participants' dietary nutrient intake. Fasting blood samples were also collected for lipid profile assessment. All participants performed N-back (0- and 1-back) working memory tasks during fMRI scanning. DLPFC (Brodmann's areas 9 and 46, and inferior, middle, and superior frontal gyrus) was identified as a region of interest for analysis. RESULTS: Positive associations were observed between dietary intake of energy, protein, cholesterol, vitamins B6 and B12, potassium, iron, phosphorus, magnesium, and HDL-C with DLPFC activation (P<0.05). Multivariate analysis showed that vitamin B6 intake, ß=0.505, t (14)=3.29, P=0.023, and Digit Symbol score, ß=0.413, t (14)=2.89, P=0.045; R 2=0.748, were positively related to DLPFC activation. CONCLUSION: Increased vitamin B6 intake and cognitive processing speed were related to greater activation in the DLPFC region, which was responsible for working memory, executive function, attention, planning, and decision making. Further studies are needed to elucidate the mechanisms underlying the association.


Assuntos
HDL-Colesterol/sangue , Cognição , Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Vitamina B 6/administração & dosagem , Idoso , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Dieta , Registros de Dieta , Humanos , Imageamento por Ressonância Magnética , Memória de Curto Prazo , Pessoa de Meia-Idade , Nutrientes/administração & dosagem , Córtex Pré-Frontal/fisiopatologia
20.
J Alzheimers Dis ; 70(s1): S43-S62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30594926

RESUMO

BACKGROUND: Many studies on biochemical and psychological variables have aimed to elucidate the association between aging and cognitive function. Demographic differences and protein expression have been reported to play a role in determining the cognitive capability of a population. OBJECTIVE: This study aimed to determine the effect of age on the protein profile of Malay individuals and its association with cognitive competency. METHODS: A total of 160 individuals were recruited and grouped accordingly. Cognitive competency of each subject was assessed with several neuropsychological tests. Plasma samples were collected and analyzed with Q Exactive HF Orbitrap. Proteins were identified and quantitated with MaxQuant and further analyzed with Perseus to determine differentially expressed proteins. PANTHER, Reactome, and STRING were applied for bioinformatics output. RESULTS: Our data showed that the Malay individuals are vulnerable to the deterioration of cognitive function with aging, and most of the proteins were differentially expressed in concordance. Several physiological components and pathways were shown to be involved, giving a hint of a promising interpretation on the induction of aging toward the state of the Malays' cognitive function. Nevertheless, some proteins have shown a considerable interaction with the generated protein network, which provides a direction of focus for further investigation. CONCLUSION: This study demonstrated notable changes in the expression of several proteins as age increased. These changes provide a promising platform for understanding the biochemical factors affecting cognitive function in the Malay population. The exhibited network of protein-protein interaction suggests the possibility of implementing regulatory intervention in ameliorating Malay cognitive function.


Assuntos
Envelhecimento/psicologia , Cognição/fisiologia , Proteoma , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Estudos Transversais , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Proteômica , Espectrometria de Massas em Tandem
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