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1.
Aging Clin Exp Res ; 35(11): 2333-2348, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37801265

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a debilitating neurodegenerative disease. Early diagnosis of AD and its precursor, mild cognitive impairment (MCI), is crucial for timely intervention and management. Radiomics involves extracting quantitative features from medical images and analyzing them using advanced computational algorithms. These characteristics have the potential to serve as biomarkers for disease classification, treatment response prediction, and patient stratification. Of note, Magnetic resonance imaging (MRI) radiomics showed a promising result for diagnosing and classifying AD, and MCI from normal subjects. Thus, we aimed to systematically evaluate the diagnostic performance of the MRI radiomics for this task. METHODS AND MATERIALS: A comprehensive search of the current literature was conducted using relevant keywords in PubMed/MEDLINE, Embase, Scopus, and Web of Science databases from inception to August 5, 2023. Original studies discussing the diagnostic performance of MRI radiomics for the classification of AD, MCI, and normal subjects were included. Method quality was evaluated with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) and the Radiomics Quality Score (RQS) tools. RESULTS: We identified 13 studies that met the inclusion criteria, involving a total of 5448 participants. The overall quality of the included studies was moderate to high. The pooled sensitivity and specificity of MRI radiomics for differentiating AD from normal subjects were 0.92 (95% CI [0.85; 0.96]) and 0.91 (95% CI [0.85; 0.95]), respectively. The pooled sensitivity and specificity of MRI radiomics for differentiating MCI from normal subjects were 0.74 (95% CI [0.60; 0.85]) and 0.79 (95% CI [0.70; 0.86]), respectively. Also, the pooled sensitivity and specificity of MRI radiomics for differentiating AD from MCI were 0.73 (95% CI [0.64; 0.80]) and 0.79 (95% CI [0.64; 0.90]), respectively. CONCLUSION: MRI radiomics has promising diagnostic performance in differentiating AD, MCI, and normal subjects. It can potentially serve as a non-invasive and reliable tool for early diagnosis and classification of AD and MCI.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/diagnóstico , Disfunção Cognitiva/diagnóstico , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade
2.
Cancers (Basel) ; 15(18)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37760399

RESUMO

Glioma and glioblastoma multiform (GBM) remain among the most debilitating and life-threatening brain tumors. Despite advances in diagnosing approaches, patient follow-up after treatment (surgery and chemoradiation) is still challenging for differentiation between tumor progression/recurrence, pseudoprogression, and radionecrosis. Radiomics emerges as a promising tool in initial diagnosis, grading, and survival prediction in patients with glioma and can help differentiate these post-treatment scenarios. Preliminary published studies are promising about the role of radiomics in post-treatment glioma/GBM. However, this field faces significant challenges, including a lack of evidence-based solid data, scattering publication, heterogeneity of studies, and small sample sizes. The present review explores radiomics's capabilities in following patients with glioma/GBM status post-treatment and to differentiate tumor progression, recurrence, pseudoprogression, and radionecrosis.

3.
BMC Cancer ; 23(1): 627, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37407931

RESUMO

BACKGROUND: The COVID-19 pandemic has affected all aspects of the healthcare system, including prevention, treatment, rehabilitation of diseases and health education; access to essential therapies; allocation of finance & facilities to health issues, and governance of diseases, including COVID-19 and other diseases. Consequently, the burden of COVID-19 was not only attributable to the multiorgan involvement and detailed presentation of the disease but also to the inadequate management of other diseases resulting from the exclusive allocation of resources and medical personnel to the pandemic crisis. Over the mentioned period, one observed deficiency was the lack of public and official favor for conventional screening protocols. To this end, this study aims to evaluate the impact of the COVID-19 pandemic on colorectal cancer (CRC) screening protocols at Shahid Beheshti University of Medical Sciences in Tehran, Iran, in an effort to identify individuals at risk for CRC and provide them with intensive screening and therapy. METHODS: This is an observational study comparing the number of candidates for CRC screening referred to primary, secondary, and tertiary health-care centers under supervision of Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran in a 2-year interval before and after COVID-19 pandemics. Patients with intermediate- and high-risk criteria for colorectal cancer were included in the study and were screened by fecal immunochemical test. Patients with positive or indeterminate fecal test results were further evaluated with colonoscopy in research institute for gastroenterology and liver diseases where is a tertiary referral center for CRC screening. Finally, the decrease percentage of screening tests and endoscopic findings during the pandemic period compared to pre-pandemic period was calculated and interpreted. RESULTS: A significant decrease in the number of performed fecal immunochemical tests (FITs), referred positive FITs, and referred patients with positive alarm signs to the Research Institute of Gastroenterology and Liver Diseases (RIGLD) center inevitably led to a considerable decrease in the number of endoscopic findings, including high-risk adenomas, sessile serrated polyps, and even early-stage colorectal cancers (CRCs). CONCLUSION: The disruption of screening protocols caused by the COVID-19 pandemic appears to increase the number of patients with high-grade and end-stage CRCs referred in the near future.


Assuntos
COVID-19 , Neoplasias Colorretais , Humanos , COVID-19/diagnóstico , COVID-19/epidemiologia , Irã (Geográfico)/epidemiologia , Pandemias , Detecção Precoce de Câncer/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Colonoscopia , Sangue Oculto , Programas de Rastreamento/métodos
4.
Biomed Eng Online ; 22(1): 68, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430259

RESUMO

BACKGROUND: Osteoporosis is a significant health problem in the skeletal system, associated with bone tissue changes and its strength. Machine Learning (ML), on the other hand, has been accompanied by improvements in recent years and has been in the spotlight. This study is designed to investigate the Diagnostic Test Accuracy (DTA) of ML to detect osteoporosis through the hip dual-energy X-ray absorptiometry (DXA) images. METHODS: The ISI Web of Science, PubMed, Scopus, Cochrane Library, IEEE Xplore Digital Library, CINAHL, Science Direct, PROSPERO, and EMBASE were systematically searched until June 2023 for studies that tested the diagnostic precision of ML model-assisted for predicting an osteoporosis diagnosis. RESULTS: The pooled sensitivity of univariate analysis of seven studies was 0.844 (95% CI 0.791 to 0.885, I2 = 94% for 7 studies). The pooled specificity of univariate analysis was 0.781 (95% CI 0.732 to 0.824, I2 = 98% for 7 studies). The pooled diagnostic odds ratio (DOR) was 18.91 (95% CI 14.22 to 25.14, I2 = 93% for 7 studies). The pooled mean positive likelihood ratio (LR+) and the negative likelihood ratio (LR-) were 3.7 and 0.22, respectively. Also, the summary receiver operating characteristics (sROC) of the bivariate model has an AUC of 0.878. CONCLUSION: Osteoporosis can be diagnosed by ML with acceptable accuracy, and hip fracture prediction was improved via training in an Architecture Learning Network (ALN).


Assuntos
Fraturas do Quadril , Osteoporose , Ossos Pélvicos , Humanos , Osteoporose/diagnóstico por imagem , Algoritmos , Aprendizado de Máquina
5.
Radiol Case Rep ; 18(6): 2259-2263, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37123042

RESUMO

Anaplastic lymphoma kinase (ALK)-positive histiocytosis is an uncommon condition, recently considered a separate condition from other histiocytosis by WHO 5th edition. It can involve intracranial structures. This manuscript describes a case of ALK-positive histiocytosis of the cavernous sinus, focusing on the radiologic and pathologic presentation of the entity. Our case had MRI manifestations mimicking meningioma, metastasis, and Langerhans histiocytosis. On CT imaging, benign osseous remodeling of the cavernous sinus was detected, which can be helpful in differentiating it from more common meningioma.

6.
Iran J Child Neurol ; 17(2): 111-117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37091465

RESUMO

Objectives: Computed tomography (CT) scans are used more frequently in medical centers, increasing unnecessary requests for it as a first-line evaluation. This study aimed to investigate the rate and prevalence of abnormal findings in a brain CT scan in children at the Children's Hospital of Tabriz, Iran. Materials &Methods: This study was a cross-sectional descriptive-analytical study that included all children under 15 years old undergoing a brain CT scan at the Children's Hospital of Tabriz, Iran. All patients who fulfilled the inclusion criteria and were referred to the Children's Hospital of Tabriz during the spring of 2018 entered the study. Age, gender, patient history, and clinical findings were examined. In the next step, the results of each patient's CT scan were evaluated. Results: In this study, 108 patients were studied with a median age of 18.0 months. CT scan results were normal in seventy-four cases (68.5%), hydrocephalus was seen in 15 (13.9%), and benign infantile hydrocephalus was seen in eight (7.4%). The study revealed a statistically significant relationship between patient history and CT scan results (p=0.017). A statistically significant relationship was observed between the clinical findings and CT scan results (p=0.042). Conclusion: Brain CT scans have more abnormal findings in patients with positive clinical findings. Although a CT scan is a highly sensitive and specificmodality in diagnosing central nervous system (CNS) abnormalities, its value depends on the underlying medical history and physical exam.

7.
Top Magn Reson Imaging ; 32(2): 15-26, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-37093700

RESUMO

ABSTRACT: Functional 1H magnetic resonance spectroscopy (fMRS) is a derivative of dynamic MRS imaging. This modality links physiologic metabolic responses with available activity and measures absolute or relative concentrations of various metabolites. According to clinical evidence, the mitochondrial glycolysis pathway is disrupted in many nervous system disorders, especially Alzheimer disease, resulting in the activation of anaerobic glycolysis and an increased rate of lactate production. Our study evaluates fMRS with J-editing as a cutting-edge technique to detect lactate in Alzheimer disease. In this modality, functional activation is highlighted by signal subtractions of lipids and macromolecules, which yields a much higher signal-to-noise ratio and enables better detection of trace levels of lactate compared with other modalities. However, until now, clinical evidence is not conclusive regarding the widespread use of this diagnostic method. The complex machinery of cellular and noncellular modulators in lactate metabolism has obscured the potential roles fMRS imaging can have in dementia diagnosis. Recent developments in MRI imaging such as the advent of 7 Tesla machines and new image reconstruction methods, coupled with a renewed interest in the molecular and cellular basis of Alzheimer disease, have reinvigorated the drive to establish new clinical options for the early detection of Alzheimer disease. Based on the latter, lactate has the potential to be investigated as a novel diagnostic and prognostic marker for Alzheimer disease.


Assuntos
Doença de Alzheimer , Ácido Láctico , Humanos , Ácido Láctico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética
8.
J Biomed Phys Eng ; 13(1): 3-16, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36818013

RESUMO

Background: Alzheimer's disease (AD) is one of the most significant public health concerns and tremendous economic challenges. Studies conducted over the past decades show that exposure to radiofrequency electromagnetic fields (RF-EMFs) may relieve AD symptoms. Objective: To determine if exposure to RF-EMFs emitted by cellphones affect the risk of AD. Material and Methods: In this review, all relevant published articles reporting an association of cell phone use with AD were studied. We systematically searched international datasets to identify relevant studies. Finally, 33 studies were included in the review. Our review discusses the effects of RF-EMFs on the amyloid ß (Aß), oxidative stress, apoptosis, reactive oxygen species (ROS), neuronal death, and astrocyte responses. Moreover, the role of exposure parameters, including the type of exposure, its duration, and specific absorption rate (SAR), are discussed. Results: Progressive factors of AD such as Aß, myelin basic protein (MBP), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and neurofilament light polypeptide (NFL) were decreased. While tau protein showed no change, factors affecting brain activity such as glial fibrillary acidic protein (GFAP), mitogen-activated protein kinases (MAPKs), cerebral blood flow (CBF), brain temperature, and neuronal activity were increased. Conclusion: Exposure to low levels of RF-EMFs can reduce the risk of AD by increasing MAPK and GFAP and decreasing MBP. Considering the role of apoptosis in AD and the effect of RF-EMF on the progression of the process, this review indicates the positive effect of these exposures.

10.
Iran J Parasitol ; 15(3): 374-382, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082802

RESUMO

BACKGROUND: We aimed to detect Toxoplasma gondii in ovine aborted fetuses and evaluate its genetic variations in the southwest of Iran. METHODS: This cross-sectional study was performed on 100 aborted ovine fetuses collected from the different region of Kohgiluyeh and Boyer-Ahmad Province, Iran, in lambing season during 2017 and 2018. DNA was extracted from the brain samples of all of the aborted fetuses and PCR amplified, targeting a 529 bp repetitive element gene of T. gondii. Moreover, to find out the heterogeneity of the positive samples, PCR-DNA amplification of the two main genetic markers, B1 and GRA6, of T. gondii were performed. Nucleotide sequencing and phylogenetic analysis were performed, using the BLAST program and MEGA-X software. RESULTS: The 529 bp gene of T. gondii was detected in 2 out of 100 (2%) of the ovine aborted samples. The sequences analysis of GRA6 and B1 genes revealed that both isolates from the aborted fetuses of sheep belonged to type I of T. gondii. Intra-divergence was more seen in GRA6 gene whereas less divergence was observed in B1 gene. CONCLUSION: Congenital infection with Type I of T. gondii during the neonatal period is associated with abortion in ovine. Evaluation of more aborted samples from broader geographical areas is needed to elucidate the molecular epidemiology and also the genotypes of T. gondii associated with abortion.

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