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Putamen iron quantification in diseases with neurodegeneration: a meta-analysis of the quantitative susceptibility mapping technique. Brain Imaging Behav 2024:10.1007/s11682-024-00895-6. [PMID: 38758278 DOI: 10.1007/s11682-024-00895-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2024] [Indexed: 05/18/2024]
Abstract
Quantitative susceptibility mapping (QSM) is an MRI technique that accurately measures iron concentration in brain tissues. This meta-analysis synthesized evidence from 30 studies that used QSM to quantify the iron levels in the putamen. The PRISMA statement was adhered to when conducting the systematic reviews and meta-analyses. We conducted a meta-analysis using a random-effects model, as well as subgroup analyses (disease type, geographic region, field strength, coil, disease type, age, and sex) and sensitivity analysis. A total of 1247 patients and 1035 controls were included in the study. Pooled results showed a standardized mean difference (SMD) of 0.41 (95% CI 0.19 to 0.64), with the strongest effect seen in Alzheimer's disease (AD) at 1.01 (95% CI 0.50 to 1.52). Relapsing-remitting multiple sclerosis (RRMS) also showed increased putaminal iron at 0.37 (95% CI 0.177 to 0.58). No significant differences were observed in Parkinson's disease (PD). No significant differences were found between subgroups based on geographic region, field strength, coil, disease type, age, and sex. The studies revealed significant heterogeneity, with field strength as the primary source, while other factors, such as disease type, location, age, sex, and coil type, may have contributed. The sensitivity analysis showed that these factors did not have a significant influence on the overall results. In summary, this meta-analysis supports abnormalities in putaminal iron content across different diseases with neurodegeneration, especially AD and RRMS, as measured by QSM. This highlights the potential of QSM as an imaging biomarker to better understand disease mechanisms involving disturbances in brain iron homeostasis.
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Post-COVID-19 conditions: a systematic review on advanced magnetic resonance neuroimaging findings. Neurol Sci 2024; 45:1815-1833. [PMID: 38421524 DOI: 10.1007/s10072-024-07427-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/23/2024] [Indexed: 03/02/2024]
Abstract
Post-COVID conditions (PCCs) cover a wide spectrum of lingering symptoms experienced by survivors of coronavirus disease 2019 (COVID-19). Neurological and neuropsychiatric sequelae are common in PCCs. Advanced magnetic resonance imaging (MRI) techniques can reveal subtle alterations in brain structure, function, and perfusion that underlie these sequelae. This systematic review aimed to synthesize findings from studies that used advanced MRI to characterize brain changes in individuals with PCCs. A detailed literature search was conducted in the PubMed and Scopus databases to identify relevant studies that used advanced MRI modalities, such as structural MRI (sMRI), diffusion tensor imaging (DTI), functional MRI (fMRI), and perfusion-weighted imaging (PWI), to evaluate brain changes in PCCs. Twenty-five studies met the inclusion criteria, comprising 1219 participants with PCCs. The most consistent findings from sMRI were reduced gray matter volume (GMV) and cortical thickness (CTh) in cortical and subcortical regions. DTI frequently reveals increased mean diffusivity (MD), radial diffusivity (RD), and decreased fractional anisotropy (FA) in white matter tracts (WMTs) such as the corpus callosum, corona radiata, and superior longitudinal fasciculus. fMRI demonstrated altered functional connectivity (FC) within the default mode, salience, frontoparietal, somatomotor, subcortical, and cerebellar networks. PWI showed decreased cerebral blood flow (CBF) in the frontotemporal area, thalamus, and basal ganglia. Advanced MRI shows changes in the brain networks and regions of the PCCs, which may cause neurological and neuropsychiatric problems. Multimodal neuroimaging may help understand brain-behavior relationships. Longitudinal studies are necessary to better understand the progression of these brain anomalies.
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Parkinson's disease and Parkinsonism syndromes: Evaluating iron deposition in the putamen using magnetic susceptibility MRI techniques - A systematic review and literature analysis. Heliyon 2024; 10:e27950. [PMID: 38689949 PMCID: PMC11059419 DOI: 10.1016/j.heliyon.2024.e27950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 02/29/2024] [Accepted: 03/08/2024] [Indexed: 05/02/2024] Open
Abstract
Magnetic resonance imaging (MRI) techniques, such as quantitative susceptibility mapping (QSM) and susceptibility-weighted imaging (SWI), can detect iron deposition in the brain. Iron accumulation in the putamen (PUT) can contribute to the pathogenesis of Parkinson's disease (PD) and atypical Parkinsonian disorders. This systematic review aimed to synthesize evidence on iron deposition in the PUT assessed by MRI susceptibility techniques in PD and Parkinsonism syndromes. The PubMed and Scopus databases were searched for relevant studies. Thirty-four studies from January 2007 to October 2023 that used QSM, SWI, or other MRI susceptibility methods to measure putaminal iron in PD, progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and healthy controls (HCs) were included. Most studies have found increased putaminal iron levels in PD patients versus HCs based on higher quantitative susceptibility. Putaminal iron accumulation correlates with worse motor scores and cognitive decline in patients with PD. Evidence regarding differences in susceptibility between PD and atypical Parkinsonism is emerging, with several studies showing greater putaminal iron deposition in PSP and MSA than in PD patients. Alterations in putaminal iron levels help to distinguish these disorders from PD. Increased putaminal iron levels appear to be associated with increased disease severity and progression. Thus, magnetic susceptibility MRI techniques can detect abnormal iron accumulation in the PUT of patients with Parkinsonism. Moreover, quantifying putaminal susceptibility may serve as an MRI biomarker to monitor motor and cognitive changes in PD and aid in the differential diagnosis of Parkinsonian disorders.
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Thalamic Alterations in Motor Neuron Diseases: A Systematic Review of MRI Findings. J Integr Neurosci 2024; 23:77. [PMID: 38682227 DOI: 10.31083/j.jin2304077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/03/2024] [Accepted: 01/09/2024] [Indexed: 05/01/2024] Open
Abstract
BACKGROUND Motor neuron diseases (MNDs) are progressive neurodegenerative disorders characterized by motor impairment and non-motor symptoms. The involvement of the thalamus in MNDs, especially in conditions such as amyotrophic lateral sclerosis (ALS), and its interaction with frontotemporal dementia (FTD), has garnered increasing research interest. This systematic review analyzed magnetic resonance imaging (MRI) studies that focused on thalamic alterations in MNDs to understand the significance of these changes and their correlation with clinical outcomes. METHODS Following PRISMA 2020 guidelines, the PubMed and Scopus databases were searched from inception to June 2023 for studies related to MRI findings in the thalamus of patients with MNDs. Eligible studies included adult patients diagnosed with ALS or other forms of MND who underwent brain MRI, with outcomes related to thalamic alterations. Studies were evaluated for risk of bias using the Newcastle-Ottawa scale. RESULTS A total of 52 studies (including 3009 MND patients and 2181 healthy controls) used various MRI techniques, including volumetric analysis, diffusion tensor imaging, and functional MRI, to measure thalamic volume, connectivity, and other alterations. This review confirmed significant thalamic changes in MNDs, such as atrophy and microstructural degradation, which are associated with disease severity, progression, and functional disability. Thalamic involvement varies across different MND subtypes and is influenced by the presence of cognitive impairment and mutations in genes including chromosome 9 open reading frame 72 (C9orf72). The synthesis of findings across studies indicates that thalamic pathology is a prevalent early biomarker of MNDs that contributes to motor and cognitive deficits. The thalamus is a promising target for monitoring as its dysfunction underpins a variety of clinical symptoms in MNDs. CONCLUSIONS Thalamic alterations provide valuable insights into the pathophysiology and progression of MNDs. Multimodal MRI techniques are potent tools for detecting dynamic thalamic changes, indicating structural integrity, connectivity disruption, and metabolic activity.
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Breast percent density changes in digital mammography pre- and post-radiotherapy. J Med Radiat Sci 2024. [PMID: 38571377 DOI: 10.1002/jmrs.788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 03/20/2024] [Indexed: 04/05/2024] Open
Abstract
INTRODUCTION Breast cancer (BC), the most frequently diagnosed malignancy among women worldwide, presents a public health challenge and affects mortality rates. Breast-conserving therapy (BCT) is a common treatment, but the risk from residual disease necessitates radiotherapy. Digital mammography monitors treatment response by identifying post-operative and radiotherapy tissue alterations, but accurate assessment of mammographic density remains a challenge. This study used OpenBreast to measure percent density (PD), offering insights into changes in mammographic density before and after BCT with radiation therapy. METHODS This retrospective analysis included 92 female patients with BC who underwent BCT, chemotherapy, and radiotherapy, excluding those who received hormonal therapy or bilateral BCT. Percent/percentage density measurements were extracted using OpenBreast, an automated software that applies computational techniques to density analyses. Data were analysed at baseline, 3 months, and 15 months post-treatment using standardised mean difference (SMD) with Cohen's d, chi-square, and paired sample t-tests. The predictive power of PD changes for BC was measured based on the receiver operating characteristic (ROC) curve analysis. RESULTS The mean age was 53.2 years. There were no significant differences in PD between the periods. Standardised mean difference analysis revealed no significant changes in the SMD for PD before treatment compared with 3- and 15-months post-treatment. Although PD increased numerically after radiotherapy, ROC analysis revealed optimal sensitivity at 15 months post-treatment for detecting changes in breast density. CONCLUSIONS This study utilised an automated breast density segmentation tool to assess the changes in mammographic density before and after BC treatment. No significant differences in the density were observed during the short-term follow-up period. However, the results suggest that quantitative density assessment could be valuable for long-term monitoring of treatment effects. The study underscores the necessity for larger and longitudinal studies to accurately measure and validate the effectiveness of quantitative methods in clinical BC management.
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Quantitative susceptibility mapping for iron monitoring of multiple subcortical nuclei in type 2 diabetes mellitus: a systematic review and meta-analysis. Front Endocrinol (Lausanne) 2024; 15:1331831. [PMID: 38510699 PMCID: PMC10950952 DOI: 10.3389/fendo.2024.1331831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 02/19/2024] [Indexed: 03/22/2024] Open
Abstract
Introduction Iron accumulation in the brain has been linked to diabetes, but its role in subcortical structures involved in motor and cognitive functions remains unclear. Quantitative susceptibility mapping (QSM) allows the non-invasive quantification of iron deposition in the brain. This systematic review and meta-analysis examined magnetic susceptibility measured by QSM in the subcortical nuclei of patients with type 2 diabetes mellitus (T2DM) compared with controls. Methods PubMed, Scopus, and Web of Science databases were systematically searched [following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines] for studies reporting QSM values in the deep gray matter (DGM) regions of patients with T2DM and controls. Pooled standardized mean differences (SMDs) for susceptibility were calculated using fixed-effects meta-analysis models, and heterogeneity was assessed using I2. Sensitivity analyses were conducted, and publication bias was evaluated using Begg's and Egger's tests. Results Six studies including 192 patients with T2DM and 245 controls were included. This study found a significant increase in iron deposition in the subcortical nuclei of patients with T2DM compared to the control group. The study found moderate increases in the putamen (SMD = 0.53, 95% CI 0.33 to 0.72, p = 0.00) and dentate nucleus (SMD = 0.56, 95% CI 0.27 to 0.85, p = 0.00) but weak associations between increased iron levels in the caudate nucleus (SMD = 0.32, 95% CI 0.13 to 0.52, p = 0.00) and red nucleus (SMD = 0.22, 95% CI 0.00 0.44, p = 0.05). No statistical significance was found for iron deposition alterations in the globus pallidus (SMD = 0.19; 95% CI -0.01 to 0.38; p = 0.06) and substantia nigra (SMD = 0.12, 95% CI -0.10, 0.34, p = 0.29). Sensitivity analysis showed that the findings remained unaffected by individual studies, and consistent increases were observed in multiple subcortical areas. Discussion QSM revealed an increase in iron in the DGM/subcortical nuclei in T2DM patients versus controls, particularly in the motor and cognitive nuclei, including the putamen, dentate nucleus, caudate nucleus, and red nucleus. Thus, QSM may serve as a potential biomarker for iron accumulation in T2DM patients. However, further research is needed to validate these findings.
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Advanced magnetic resonance neuroimaging techniques: feasibility and applications in long or post-COVID-19 syndrome - a review. Ann Med Surg (Lond) 2024; 86:1584-1589. [PMID: 38463042 PMCID: PMC10923379 DOI: 10.1097/ms9.0000000000001808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Accepted: 01/29/2024] [Indexed: 03/12/2024] Open
Abstract
Long-term or post-COVID-19 syndrome (PCS) is a condition that affects people infected with SARS‑CoV‑2, the virus that causes COVID-19. PCS is characterized by a wide range of persistent or new symptoms that last months after the initial infection, such as fatigue, shortness of breath, cognitive dysfunction, and pain. Advanced magnetic resonance (MR) neuroimaging techniques can provide valuable information on the structural and functional changes in the brain associated with PCS as well as potential biomarkers for diagnosis and prognosis. In this review, we discuss the feasibility and applications of various advanced MR neuroimaging techniques in PCS, including perfusion-weighted imaging (PWI), diffusion-weighted imaging (DWI), susceptibility-weighted imaging (SWI), functional MR imaging (fMRI), diffusion tensor imaging (DTI), and tractography. We summarize the current evidence on neuroimaging findings in PCS, the challenges and limitations of these techniques, and the future directions for research and clinical practice. Although still uncertain, advanced MRI techniques show promise for gaining insight into the pathophysiology and guiding the management of COVID-19 syndrome, pending larger validation studies.
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Brain metastases from breast cancer using magnetic resonance imaging: A systematic review. J Med Radiat Sci 2024; 71:133-141. [PMID: 37563948 PMCID: PMC10920938 DOI: 10.1002/jmrs.715] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 08/01/2023] [Indexed: 08/12/2023] Open
Abstract
Despite improvements in imaging and treatment approaches, brain metastases (BMs) continue to be the primary cause of mortality and morbidity in about 20% of adult cancer patients. This research aimed to review the magnetic resonance imaging (MRI) and clinical characteristics of BMs resulting from breast cancer (BC). A systematic review of original research articles published from January 2000 to June 2023. We selected studies that reported MRI findings of BMs in BC patients. We excluded reviews, case reports, books/book chapters, animal studies and irrelevant records. We identified 24 studies that included 1580 BC patients with BMs. T1-weighted (T1-w) (pre- and postcontrast), T2-weighted (T2-w), fluid-attenuated inversion recovery (FLAIR) and T2*-weighted (T2*-w) was used to measure the lesion size, shape and area. In other studies, advanced structural techniques including diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI) and susceptibility-weighted imaging (SWI) were used to more precisely and sensitively evaluate the pathological area. Furthermore, functional and metabolic techniques like functional MRI (fMRI), magnetic resonance spectroscopy (MRS) and perfusion-weighted imaging (PWI) have also been utilised. The MRI findings of BMs varied depending on the MRI technique, the BC subtype, the lesion size and shape, the presence of haemorrhage or necrosis and the comparison with other brain tumours. Some MRI findings were associated with prognosis, recurrence or cognitive impairment in BC patients with BMs. MRI detects, characterises and monitors BMs from BC. Findings vary by MRI technique, BC subtype, lesion characteristics and comparison with other brain tumours. More research should validate emerging MRI techniques, determine the clinical implications of findings and explore the underlying mechanisms and biology of BMs from BC. MRI is a valuable tool for diagnosis, targeted therapy and studying BC metastasis.
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Marker-controlled watershed algorithm and fuzzy C-means clustering machine learning: automated segmentation of glioblastoma from MRI images in a case series. Ann Med Surg (Lond) 2024; 86:1460-1475. [PMID: 38463066 PMCID: PMC10923355 DOI: 10.1097/ms9.0000000000001756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 01/16/2024] [Indexed: 03/12/2024] Open
Abstract
Introduction and importance Automated segmentation of glioblastoma multiforme (GBM) from MRI images is crucial for accurate diagnosis and treatment planning. This paper presents a new and innovative approach for automating the segmentation of GBM from MRI images using the marker-controlled watershed segmentation (MCWS) algorithm. Case presentation and methods The technique involves several image processing techniques, including adaptive thresholding, morphological filtering, gradient magnitude calculation, and regional maxima identification. The MCWS algorithm efficiently segments images based on local intensity structures using the watershed transform, and fuzzy c-means (FCM) clustering improves segmentation accuracy. The presented approach achieved improved segmentation accuracy in detecting and segmenting GBM tumours from axial T2-weighted (T2-w) MRI images, as demonstrated by the mean characteristics performance metrics for GBM segmentation (sensitivity: 0.9905, specificity: 0.9483, accuracy: 0.9508, precision: 0.5481, F_measure: 0.7052, and jaccard: 0.9340). Clinical discussion The results of this study underline the importance of reliable and accurate image segmentation for effective diagnosis and treatment planning of GBM tumours. Conclusion The MCWS technique provides an effective and efficient approach for the segmentation of challenging medical images.
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Iron quantification in basal ganglia: quantitative susceptibility mapping as a potential biomarker for Alzheimer's disease - a systematic review and meta-analysis. Front Neurosci 2024; 18:1338891. [PMID: 38469572 PMCID: PMC10925682 DOI: 10.3389/fnins.2024.1338891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Accepted: 02/13/2024] [Indexed: 03/13/2024] Open
Abstract
Introduction Alzheimer's disease (AD), characterized by distinctive pathologies such as amyloid-β plaques and tau tangles, also involves deregulation of iron homeostasis, which may accelerate neurodegeneration. This meta-analysis evaluated the use of quantitative susceptibility mapping (QSM) to detect iron accumulation in the deep gray matter (DGM) of the basal ganglia in AD, contributing to a better understanding of AD progression, and potentially leading to new diagnostic and therapeutic approaches. Methods Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched the PubMed, Scopus, Web of Sciences, and Google Scholar databases up to October 2023 for studies employing QSM in AD research. Eligibility criteria were based on the PECO framework, and we included studies assessing alterations in magnetic susceptibility indicative of iron accumulation in the DGM of patients with AD. After initial screening and quality assessment using the Newcastle-Ottawa Scale, a meta-analysis was conducted to compare iron levels between patients with AD and healthy controls (HCs) using a random-effects model. Results The meta-analysis included nine studies comprising 267 patients with AD and 272 HCs. There were significantly higher QSM values, indicating greater iron deposition, in the putamen (standardized mean difference (SMD) = 1.23; 95% CI: 0.62 to 1.84; p = 0.00), globus pallidus (SMD = 0.79; 95% CI: 0.07 to 1.52; p = 0.03), and caudate nucleus (SMD = 0.72; 95% CI: 0.39 to 1.06; p = 0.00) of AD patients compared to HCs. However, no significant differences were found in the thalamus (SMD = 1.00; 95% CI: -0.42 to 2.43; p = 0.17). The sensitivity analysis indicated that no single study impacted the overall results. Age was identified as a major contributor to heterogeneity across all basal ganglia nuclei in subgroup analysis. Older age (>69 years) and lower male percentage (≤30%) were associated with greater putamen iron increase in patients with AD. Conclusion The study suggests that excessive iron deposition is linked to the basal ganglia in AD, especially the putamen. The study underscores the complex nature of AD pathology and the accumulation of iron, influenced by age, sex, and regional differences, necessitating further research for a comprehensive understanding.
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MRI biomarkers and neuropsychological assessments of hippocampal and parahippocampal regions affected by ALS: A systematic review. CNS Neurosci Ther 2024; 30:e14578. [PMID: 38334254 PMCID: PMC10853901 DOI: 10.1111/cns.14578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 12/11/2023] [Accepted: 12/13/2023] [Indexed: 02/10/2024] Open
Abstract
BACKGROUND AND OBJECTIVE Amyotrophic lateral sclerosis (ALS) is a progressive motor and extra-motor neurodegenerative disease. This systematic review aimed to examine MRI biomarkers and neuropsychological assessments of the hippocampal and parahippocampal regions in patients with ALS. METHODS A systematic review was conducted in the Scopus and PubMed databases for studies published between January 2000 and July 2023. The inclusion criteria were (1) MRI studies to assess hippocampal and parahippocampal regions in ALS patients, and (2) studies reporting neuropsychological data in patients with ALS. RESULTS A total of 46 studies were included. Structural MRI revealed hippocampal atrophy, especially in ALS-FTD, involving specific subregions (CA1, dentate gyrus). Disease progression and genetic factors impacted atrophy patterns. Diffusion tensor imaging (DTI) showed increased mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), and decreased fractional anisotropy (FA) in the hippocampal tracts and adjacent regions, indicating loss of neuronal and white matter integrity. Functional MRI (fMRI) revealed reduced functional connectivity (FC) between the hippocampus, parahippocampus, and other regions, suggesting disrupted networks. Perfusion MRI showed hypoperfusion in parahippocampal gyri. Magnetic resonance spectroscopy (MRS) found changes in the hippocampus, indicating neuronal loss. Neuropsychological tests showed associations between poorer memory and hippocampal atrophy or connectivity changes. CA1-2, dentate gyrus, and fimbria atrophy were correlated with worse memory. CONCLUSIONS The hippocampus and the connected regions are involved in ALS. Hippocampal atrophy disrupted connectivity and metabolite changes correlate with cognitive and functional decline. Specific subregions can be particularly affected. The hippocampus is a potential biomarker for disease monitoring and prognosis.
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A systematic review of brain metastases from lung cancer using magnetic resonance neuroimaging: Clinical and technical aspects. J Med Radiat Sci 2024. [PMID: 38234262 DOI: 10.1002/jmrs.756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 01/06/2024] [Indexed: 01/19/2024] Open
Abstract
INTRODUCTION Brain metastases (BMs) are common in lung cancer (LC) and are associated with poor prognosis. Magnetic resonance imaging (MRI) plays a vital role in the detection, diagnosis and management of BMs. This review summarises recent advances in MRI techniques for BMs from LC. METHODS This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive literature search was conducted in three electronic databases: PubMed, Scopus and the Web of Science. The search was limited to studies published between January 2000 and March 2023. The quality of the included studies was evaluated using appropriate tools for different study designs. A narrative synthesis was carried out to describe the key findings of the included studies. RESULTS Sixty-five studies were included. Standard MRI sequences such as T1-weighted (T1w), T2-weighted (T2w) and fluid-attenuated inversion recovery (FLAIR) were commonly used. Advanced techniques included perfusion-weighted imaging (PWI), diffusion-weighted imaging (DWI) and radiomics analysis. DWI and PWI parameters could distinguish tumour recurrence from radiation necrosis. Radiomics models predicted genetic mutations and the risk of BMs. Diagnostic accuracy was improved with deep learning (DL) approaches. Prognostic factors such as performance status and concurrent chemotherapy impacted survival. CONCLUSION Advanced MRI techniques and specialised MRI methods have emerging roles in managing BMs from LC. PWI and DWI improve diagnostic accuracy in treated BMs. Radiomics and DL facilitate personalised prognosis and treatment. Magnetic resonance imaging plays a key role in the continuum of care for BMs of patients with LC, from screening to treatment monitoring.
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An uncommon presentation of early brainstem high-grade glioma in a 33-year-old male: A case study and review of literature. Int J Surg Case Rep 2024; 114:109152. [PMID: 38141508 PMCID: PMC10800718 DOI: 10.1016/j.ijscr.2023.109152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/21/2023] [Accepted: 12/02/2023] [Indexed: 12/25/2023] Open
Abstract
INTRODUCTION AND IMPORTANCE Unlike children, high-grade brainstem glioma (HG-BSG) in adults is a rare and diverse group of tumors. They can be classified based on their location and physical characteristics, which distinguishes them from pediatric brainstem gliomas. They are rare in adults, constituting only 1 % to 2 % of intracranial gliomas. They are often aggressive and have a poor prognosis, with a median survival time of 24 months. The diagnosis of brainstem gliomas typically involves a combination of clinical evaluation and imaging studies, mainly magnetic resonance imaging (MRI), which provides detailed images and can help identify the characteristics of the tumor. CASE PRESENTATION AND METHODS We present a case study of an uncommon presentation of an early stage of HG-BSG in a 33-year-old male, who had a contrast-enhancing lesion in the ventrolateral medulla that extended to the lower aspect of the fourth ventricle and caused ventricular compression. CLINICAL DISCUSSION The findings were consistent with the literature on the current state of HG-BSG MRI findings, which typically show contrast-enhancing, hyperintense, and infiltrative lesions that involve the pons, midbrain, or medulla oblongata. The diagnosis of HG-BSG was based on clinical and radiological criteria, as the patient refused to undergo a surgical biopsy. We also performed a literature review on the current state of brainstem HG-BSG MRI findings, summarizing the main features and patterns of these tumors. CONCLUSION MRI can offer useful information regarding the tumor's location, size, and features, as well as its impact on surrounding tissues and cerebrospinal fluid circulation.
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Investigating the safety and efficacy of nerve stimulation for management of groin pain after surgical herniorrhaphy: a systematic review and meta-analysis. Hernia 2023; 27:1363-1373. [PMID: 37597107 DOI: 10.1007/s10029-023-02861-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 08/07/2023] [Indexed: 08/21/2023]
Abstract
PURPOSE Chronic post-operative inguinal pain (CPIP) following inguinal hernia repair has been a major sequela affecting 4000-48000 patients annually. Optimal management of CPIP has been a challenge, and pharmacological management particularly with opioids has shown unsatisfactory results. The main objective of this systematic review is to investigate the safety and efficacy of neuromodulation as an alternative intervention for the management of post-operative inguinal pain. METHODS A literature search was conducted by three reviewers to identify all relevant studies on the use of neuromodulatory interventions for treating post-operative inguinal pain. Data on study characteristics, neuromodulatory modalities, and patient's clinical data such as pre/post-interventional pain scores and analgesic requirements were extracted and reported. RESULTS A total of 389 patients with 357 (95.9%) males and 15 (4.1%) females were evaluated. The mean age of study participants was 47.9 ± 10.4 years. There were 187 (48.1%) and 202 (51.9%) patients allocated to the control and trial groups, respectively. The most common neuromodulation modality was TENS (4, 36.4%), followed by SCS (3, 27.3%), PNS (3, 27.3%), and acupuncture-assisted (2, 18.2%). The overall mean follow-up duration of the entire cohort was 3.8 months. The mean difference between pre-operative and post-operative VAS scores in the trial groups was 4.65 (95% Confidence Interval [CI], 2.97, 6.33), which was statistically significant (P value < 0.05). Patient-reported outcome measures showed significant responsiveness toward their treatments. CONCLUSION Nerve stimulation, in its many forms, is a safe and feasible option for the management of post-operative inguinal pain.
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Obstructive sleep apnea and attention deficits: A systematic review of magnetic resonance imaging biomarkers and neuropsychological assessments. Brain Behav 2023; 13:e3262. [PMID: 37743582 PMCID: PMC10636416 DOI: 10.1002/brb3.3262] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 09/07/2023] [Accepted: 09/12/2023] [Indexed: 09/26/2023] Open
Abstract
BACKGROUND AND OBJECTIVE Obstructive sleep apnea (OSA) is a common sleep disorder that causes intermittent hypoxia and sleep fragmentation, leading to attention impairment and other cognitive deficits. Magnetic resonance imaging (MRI) is a powerful modality that can reveal the structural and functional brain alterations associated with attention impairment in OSA patients. The objective of this systematic review is to identify and synthesize the evidence on MRI biomarkers and neuropsychological assessments of attention deficits in OSA patients. METHODS We searched the Scopus and PubMed databases for studies that used MRI to measure biomarkers related to attention alteration in OSA patients and reported qualitative and quantitative data on the association between MRI biomarkers and attention outcomes. We also included studies that found an association between neuropsychological assessments and MRI findings in OSA patients with attention deficits. RESULTS We included 19 studies that met our inclusion criteria and extracted the relevant data from each study. We categorized the studies into three groups based on the MRI modality and the cognitive domain they used: structural and diffusion tensor imaging MRI findings, functional, perfusion, and metabolic MRI findings, and neuropsychological assessment findings. CONCLUSIONS We found that OSA is associated with structural, functional, and metabolic brain alterations in multiple regions and networks that are involved in attention processing. Treatment with continuous positive airway pressure can partially reverse some of the brain changes and improve cognitive function in some domains and in some studies. This review suggests that MRI techniques and neuropsychological assessments can be useful tools for monitoring the progression and response to treatment of OSA patients.
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Automated segmentation of meningioma from contrast-enhanced T1-weighted MRI images in a case series using a marker-controlled watershed segmentation and fuzzy C-means clustering machine learning algorithm. Int J Surg Case Rep 2023; 111:108818. [PMID: 37716060 PMCID: PMC10514425 DOI: 10.1016/j.ijscr.2023.108818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/07/2023] [Accepted: 09/09/2023] [Indexed: 09/18/2023] Open
Abstract
INTRODUCTION AND IMPORTANCE Accurate segmentation of meningiomas from contrast-enhanced T1-weighted (CE T1-w) magnetic resonance imaging (MRI) is crucial for diagnosis and treatment planning. Manual segmentation is time-consuming and prone to variability. To evaluate an automated segmentation approach for meningiomas using marker-controlled watershed segmentation (MCWS) and fuzzy c-means (FCM) algorithms. CASE PRESENTATION AND METHODS CE T1-w MRI of 3 female patients (aged 59, 44, 67 years) with right frontal meningiomas were analyzed. Images were converted to grayscale and preprocessed with Otsu's thresholding and FCM clustering. MCWS segmentation was performed. Segmentation accuracy was assessed by comparing automated segmentations to manual delineations. CLINICAL DISCUSSION The approach successfully segmented meningiomas in all cases. Mean sensitivity was 0.8822, indicating accurate identification of tumors. Mean Dice similarity coefficient between Otsu's and FCM1 was 0.6599, suggesting good overlap between segmentation methods. CONCLUSION The MCWS and FCM approach enables accurate automated segmentation of meningiomas from CE T1-w MRI. With further validation on larger datasets, this could provide an efficient tool to assist in delineating meningioma boundaries for clinical management.
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Iron quantification in basal ganglia using quantitative susceptibility mapping in a patient with ALS: a case report and literature review. Front Neurosci 2023; 17:1229082. [PMID: 37877011 PMCID: PMC10593460 DOI: 10.3389/fnins.2023.1229082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 09/04/2023] [Indexed: 10/26/2023] Open
Abstract
Background Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique that can measure the magnetic susceptibility of tissues, which can reflect their iron content. QSM has been used to detect iron accumulation in cortical and subcortical brain regions. However, its application in subcortical regions such as the basal ganglia, particularly the putamen, is rare in patients with amyotrophic lateral sclerosis (ALS). Case presentation and literature review We present the case of a 40-year-old male patient with ALS who underwent an MRI for QSM. We compared his QSM images with those of a control subject and performed a quantitative analysis of the magnetic susceptibility values in the putamen regions. We also reviewed the literature on previous QSM studies in ALS and summarized their methods and findings. Our QSM analysis revealed increased magnetic susceptibility values in the bilateral putamen of the ALS patient compared to controls, indicating iron overload. This finding is consistent with previous studies reporting iron dysregulation in subcortical nuclei in ALS. We also discussed the QSM processing techniques used in our study and in the literature, highlighting their advantages and limitations. Conclusion This case report demonstrates the potential of QSM as a sensitive MRI biomarker for evaluating iron levels in subcortical regions of ALS patients. QSM can provide quantitative information on iron deposition patterns in both motor and extra-motor areas of ALS patients, which may help understand the pathophysiology of ALS and monitor disease progression. Further studies with larger samples are needed to validate these results and explore the clinical implications of QSM in ALS.
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Post-COVID-19 Vaccination CNS Magnetic Resonance Imaging Findings: A Systematic Review. THE CANADIAN JOURNAL OF INFECTIOUS DISEASES & MEDICAL MICROBIOLOGY = JOURNAL CANADIEN DES MALADIES INFECTIEUSES ET DE LA MICROBIOLOGIE MEDICALE 2023; 2023:1570830. [PMID: 37427078 PMCID: PMC10325882 DOI: 10.1155/2023/1570830] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/18/2023] [Accepted: 06/23/2023] [Indexed: 07/11/2023]
Abstract
Objective This systematic review aims to synthesize and analyze the available literature on central nervous system (CNS) magnetic resonance imaging (MRI) findings in individuals who have received COVID-19 vaccinations. Our objective is to enhance understanding of potential neurological side effects, inform clinical practice, and guide future research on the neurological implications of COVID-19 vaccination. Methods In this systematic review, we conducted a comprehensive search in PubMed, Scopus, and Web of Science from January 2020 to April 2023, using terms related to COVID-19 vaccination and CNS MRI findings. We evaluated the quality of the study, extracted relevant data, and included 89 eligible studies that covered various vaccines, demographics of patients, symptoms, and MRI findings to provide a thorough understanding of SARS-CoV-2 vaccination-related CNS problems. Results We investigated CNS MRI findings following COVID-19 vaccination across various vaccine types. Common diseases associated with post-vaccination CNS MRI findings included cerebral venous sinus thrombosis (CVST), vaccine-induced immune thrombotic thrombocytopenia (VITT), acute disseminated encephalomyelitis (ADEM), acute myelitis, autoimmune encephalitis (AE), and others. Patients presented with diverse onset symptoms and neurological manifestations. Abnormalities identified in CNS MRI findings included white matter (WM) hyperintensity. Our analysis offers a comprehensive overview of the current literature on post-vaccination CNS MRI findings. Discussion. We highlight a range of post-COVID-19 vaccination CNS MRI findings, including CVST, with a higher incidence in individuals receiving the ChAdOx1 (AstraZeneca) vaccine. Other notable observations include cases of ADEM, myelitis or transverse myelitis (TM), Guillain-Barré syndrome (GBS), and acute encephalopathy following COVID-19 vaccination. The incidence of these neurological complications is extremely rare, and the benefits of vaccination outweigh the risks. The reviewed studies were primarily case reports or case series, and thus large-scale epidemiological studies and controlled clinical trials are needed to better understand the underlying mechanisms and risk factors associated with these neurological complications following COVID-19 vaccination.
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MRI findings in movement disorders and associated sleep disturbances. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2023; 13:77-94. [PMID: 37457325 PMCID: PMC10349287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 06/22/2023] [Indexed: 07/18/2023]
Abstract
BACKGROUND One of the most useful tools for identifying sleep disturbances is neuroimaging, especially magnetic resonance imaging (MRI). This review research was to look at the role of MRI findings in movement disorders and sleep disturbances. METHODS This review collects all MRI data on movement disorders and sleep disruptions. Between 2000 and 2022, PubMed and Google Scholar were utilized to find original English publications and reviews. According to the inclusion and exclusion criteria, around 100 publications were included. We only looked at research that explored MRI modality together with movement problems, sleep disorders, and brain area involvement. Most of the information focuses on movement irregularities and sleep interruptions. RESULTS Movement disorders such as Parkinson's disease (PD), Huntington's disease (HD), neuromuscular diseases, rapid eye movement (REM) sleep behavior movement disorder (RBD), cerebellar movement disorders, and brainstem movement disorders are assessed using MRI-based neuroimaging techniques. Some of the brain areas were associated with disorders in movement abnormalities and related sleep disturbances. This review found that many people with mobility disorders also have sleep problems. Some brain areas' malfunctions may cause motor and sleep issues. CONCLUSION Neuroimaging helps us understand the sleep difficulties associated with movement disorders by examining the structural and functional implications of movement disorders and sleep disturbances.
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Neurological manifestation in COVID-19 disease with neuroimaging studies. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2023; 12:42-84. [PMID: 37213710 PMCID: PMC10195392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 04/03/2023] [Indexed: 05/23/2023]
Abstract
OBJECTIVE Magnetic resonance imaging (MRI) of the brain or spine examines the findings as well as the time interval between the onset of symptoms and other adverse effects in coronavirus disease that first appeared in 2019 (COVID-19) patients. The goal of this study is to look at studies that use neuroimaging to look at neurological and neuroradiological symptoms in COVID-19 patients. METHODS We try to put together all of the research on how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes neurological symptoms and cognitive-behavioral changes and give a full picture. RESULTS We have categorized neuroimaging findings into subtitles such as: headache and dizziness; cerebrovascular complications after stroke; Intracerebral Hemorrhage (ICH); Cerebral Microbleeds (CMBs); encephalopathy; meningitis; encephalitis and myelitis; altered mental status (AMS) and delirium; seizure; neuropsychiatric symptoms; Guillain-Barre Syndrome (GBS) and its variants; smell and taste disorders; peripheral neuropathy; Mild Cognitive Impairment (MCI); and myopathy and myositis. CONCLUSION In this review study, we talked about some MRI findings that show how COVID-19 affects the nervous system based on what we found.
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Tomographic phase and attenuation extraction for a sample composed of unknown materials using x-ray propagation-based phase-contrast imaging. OPTICS LETTERS 2022; 47:1945-1948. [PMID: 35427307 DOI: 10.1364/ol.445802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
Propagation-based phase-contrast x-ray imaging (PB-PCXI) generates image contrast by utilizing sample-imposed phase-shifts. This has proven useful when imaging weakly attenuating samples, as conventional attenuation-based imaging does not always provide adequate contrast. We present a PB-PCXI algorithm capable of extracting the x-ray attenuation β and refraction δ, components of the complex refractive index of distinct materials within an unknown sample. The method involves curve fitting an error-function-based model to a phase-retrieved interface in a PB-PCXI tomographic reconstruction, which is obtained when Paganin-type phase retrieval is applied with incorrect values of δ and β. The fit parameters can then be used to calculate true δ and β values for composite materials. This approach requires no a priori sample information, making it broadly applicable. Our PB-PCXI reconstruction is single-distance, requiring only one exposure per tomographic angle, which is important for radiosensitive samples. We apply this approach to a breast-tissue sample, recovering the refraction component δ, with 0.6-2.4% accuracy compared with theoretical values.
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Systematic Projected Shell Model Study of Even-Even Dysprosium Isotopes. ATOM INDONESIA 2022. [DOI: 10.17146/aij.2022.1190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Design and validation of a tool to assess the safety principles of working with nanomaterials in nanotechnology laboratories. Occup Med (Lond) 2022. [DOI: 10.18502/tkj.v13i3.8197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Introduction: The unique properties of nanomaterials, in addition to their applications in science and technology, can be a threat to human health and the environment. Exposure to these materials may occur in workplaces or research laboratories. It can be said that about half of people with occupational exposure to nanomaterials work in academic environments and laboratories. So, the present study was conducted to design and validate a tool to investigate the principles of working safely with nanomaterials in research laboratories.
Materials & Methods: The tool was designed using reports, instructions and articles related to " Methods of working safely with nanomaterials". The validity of the tool was assessed using Lawshe method by calculating CVI and CVR. The reliability of the instrument was evaluated using Cronbach's alpha coefficient and kappa coefficient.
Results: The tool was designed in 5 sections: "General Information", "Transportation and Storage of Nanomaterials", "Engineering Controls", "Administrative Controls" and "Personal Protection Equipment". After validation, 5 items did not get the necessary points to stay in the tool and were removed. The Cronbach's alpha value for each section of the tool was more than 0.80, indicating that the was "appropriate".
Conclusion: According to the results, it seems that the tool studied in this study is compatible for the designed purpose and is ready to be used as a questionnaire or checklist.
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Shedding light on thyroid hormone disorders and Parkinson disease pathology: mechanisms and risk factors. J Endocrinol Invest 2021; 44:1-13. [PMID: 32500445 DOI: 10.1007/s40618-020-01314-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/27/2020] [Indexed: 02/07/2023]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons. Dopaminergic system is interconnected with the hypothalamic-pituitary-thyroid axis. Dopamine (DA) upregulates thyrotropin releasing hormone (TRH) while downregulating thyroid stimulating hormone (TSH) and thyroid hormones. Moreover, TRH stimulates DA release. PD is associated with impaired regulation of TSH and thyroid hormones (TH) levels, which in turn associate with severity and different subtypes of PD, while levodopa and bromocriptine treatment can interfere with hypothalamic-pituitary-thyroid axis. Thyroid disturbances, including hypothyroidism, Hashimoto's thyroiditis (HT), hyperthyroidism and Graves' disease (GD) not only increase the risk of PD but also share some clinical signs with PD. Also, several genes including RASD2, WSB1, MAPT, GIRK2, LRRK2 and gene products like neurotensin and NOX/DUOX affect the risk for both PD and thyroid disease. Hypothyroidism is associated with obesity, hypercholesterolemia, anemia and altered cerebral blood flow which are associated with PD pathology. Herein we provide a comprehensive view on the association between PD and thyroid hormones regulation and dysregulations, hoping to provide new avenues towards targeted treatment of PD. We performed a comprehensive search in literature using Pubmed and Scopus, yielding to a total number of 36 original articles that had addressed the association between thyroid hormone disorders and PD.
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Tunable transport properties in graphene-DNA and silicene-DNA by controlling the thickness of nanopores. Chem Phys 2021. [DOI: 10.1016/j.chemphys.2020.111048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Curcumin-gold-polyethylene glycol nanoparticles as a nanosensitizer for photothermal and sonodynamic therapies: In vitro and animal model studies. Photodiagnosis Photodyn Ther 2020; 33:102139. [PMID: 33310015 DOI: 10.1016/j.pdpdt.2020.102139] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 10/21/2020] [Accepted: 12/04/2020] [Indexed: 12/18/2022]
Abstract
Photothermal and ultrasound therapies are novel non-invasive strategies for tumor treatment which are equipped with a photosensitizer and sonosensitizer subsequent activation by laser irradiation and ultrasound exposure. In this study, curcumin-gold-polyethylene glycol nanoparticles (Cur-Au NPs-PEG) were synthesized, and the dual role in photothermal (PTT) and sonodynamic (SDT) therapies of melanoma cancer was evaluated. The toxicity effect of Cur-Au NPs-PEG against a mouse malignant melanoma cell line C540 (B16/F10) was firstly inspected in vitro. Cur-Au NPs-PEG provided a hyperthermal microenvironment and generated reactive oxygen species upon PTT and STD, respectively, with representing synergism effects. Studies in vivo in a tumor-bearing animal also demonstrate the superiority of PTT and SDT in destroying melanoma tumor.
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Abstract
BACKGROUND Osteopontin (OPN) plays a critical role in cell proliferation and drug resistance in cancer treatment and hematological malignancies. In T cell acute lymphoblastic leukemia, most initial therapies can induce remission while some patients then relapse and do not respond well to chemotherapy. The sesquiterpene lactone parthenolide (PTL) can induce apoptosis in a variety of cancer cell lines via inhibition of pro-inflammatory transcription factor nuclear factor kappa B and has anti-tumor activity in acute lymphoblastic leukemia treatment. AIM To study the role of OPN in conferring in vitro resistance to PTL in Jurkat cells. METHODS Jurkat cells were cultured with 8-20 μm PTL for 48 h. Transfection with OPN siRNA was provided. Apoptosis assays were performed with Annexin V-Alexa Fluor-488/PI. Quantitative real-time polymerase chain reaction was used to measure OPN gene expression using the 2-2-ΔΔCt method. RESULTS PTL has cytotoxic and apoptotic effect on Jurkat cells with IC50 values of 16.1 μm, and growth inhibition effect of PTL does not differ significantly in combination with OPN-siRNA. OPN gene expression is not affected by PTL. CONCLUSIONS Parthenolide induces apoptosis in Jurkat cells, but inhibition of osteopontin gene expression with siRNA does not reduce apoptotic effect of parthenolide.
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Photothermal/sonodynamic therapy of melanoma tumor by a gold/manganese dioxide nanocomposite: In vitro and in vivo studies. Photodiagnosis Photodyn Ther 2020; 31:101846. [DOI: 10.1016/j.pdpdt.2020.101846] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/18/2020] [Accepted: 05/27/2020] [Indexed: 02/06/2023]
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The prevalence of human bocavirus in <2-year-old children with acute bronchiolitis. New Microbes New Infect 2020; 37:100736. [PMID: 32983545 PMCID: PMC7493080 DOI: 10.1016/j.nmni.2020.100736] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 07/24/2020] [Accepted: 07/28/2020] [Indexed: 11/23/2022] Open
Abstract
Acute bronchiolitis is one of the most common lower respiratory tract infections in children with less than 2 years of age. Nowadays, molecular methods provide an opportunity to better understand the etiology of bronchiolitis. Several viral agents including Respiratory syncytial virus (RSV), Rhinovirus, Parainfluenza and Human bocavirus (HBoV) are responsible for acute bronchiolitis. There are growing studies on the prevalence of HBoV in patients with bronchiolitis. The present systematic review and meta-analysis were conducted to determine the pooled prevalence of HBoV in the respiratory samples of children with acute bronchiolitis. A literature search was conducted in the databases of PubMed, Scopus and Web of Science to recruit studies reporting the frequency of HBoV in <2-year-old children with acute bronchiolitis from 2005 to 2019. Only studies that used polymerase chain reaction (PCR)-based methods to detect the virus in nasopharyngeal samples were included. A total of 22 studies assessing 6751 cases were analyzed. According to the meta-analysis based on the random-effects model, the overall prevalence of HBoV in children with <2 years old was obtained 13% (95% CI: 0.09-0.17). Additionally, the rates of single (as the sole organism) and mixed (in combination with other viruses) HBoV infections were 4% and 9%, respectively. This study showed a high rate of HBoV detection in children with acute bronchiolitis. This should be considered as part of a diagnostic test panel for respiratory infections in children with bronchiolitis.
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Hemolytic disease of the fetus and newborn caused by anti-Hr 0 in a 27-year-old female with Dc- phenotype: A case report. Transfus Apher Sci 2020; 60:102913. [PMID: 32943324 DOI: 10.1016/j.transci.2020.102913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 11/18/2022]
Abstract
Anti-Hr0 (Anti-Rh17) is a rare immune Immunoglobulin G (IgG) to high-frequency Rh antigens that may cause severe and often fatal Hemolytic disease of the fetus and newborn (HDFN) in D--, Dc- and DCw- mothers who have been exposed to red cells of the common Rh phenotype by transfusion or pregnancy. Several pregnant women have been affected by this antibody leading to perinatal death. Therefore, immediate and effective management of these cases is of great importance. We report a case of HDFN in a 27-year-old (G5, P3, L1), woman with Rh Dc- phenotype managed successfully using intravenous immunoglobulin (IVIg) and simple transfusions.
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Experimental and theoretical studies of free vibration of a sandwich functionally graded nanocomposite beam under thermal condition. SN APPLIED SCIENCES 2020. [DOI: 10.1007/s42452-020-3080-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Consensus on definition and severity grading of lymphatic complications after kidney transplantation. Br J Surg 2020; 107:801-811. [PMID: 32227483 DOI: 10.1002/bjs.11587] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/23/2020] [Accepted: 02/14/2020] [Indexed: 01/08/2023]
Abstract
BACKGROUND The incidence of lymphatic complications after kidney transplantation varies considerably in the literature. This is partly because a universally accepted definition has not been established. This study aimed to propose an acceptable definition and severity grading system for lymphatic complications based on their management strategy. METHODS Relevant literature published in MEDLINE and Web of Science was searched systematically. A consensus for definition and a severity grading was then sought between 20 high-volume transplant centres. RESULTS Lymphorrhoea/lymphocele was defined in 32 of 87 included studies. Sixty-three articles explained how lymphatic complications were managed, but none graded their severity. The proposed definition of lymphorrhoea was leakage of more than 50 ml fluid (not urine, blood or pus) per day from the drain, or the drain site after removal of the drain, for more than 1 week after kidney transplantation. The proposed definition of lymphocele was a fluid collection of any size near to the transplanted kidney, after urinoma, haematoma and abscess have been excluded. Grade A lymphatic complications have a minor and/or non-invasive impact on the clinical management of the patient; grade B complications require non-surgical intervention; and grade C complications require invasive surgical intervention. CONCLUSION A clear definition and severity grading for lymphatic complications after kidney transplantation was agreed. The proposed definitions should allow better comparisons between studies.
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Impact of choice of volumetry software and nodule management guidelines on recall rates in lung cancer screening. Eur J Radiol 2019; 120:108646. [DOI: 10.1016/j.ejrad.2019.108646] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 08/07/2019] [Accepted: 08/30/2019] [Indexed: 11/15/2022]
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Dysregulation of helper T lymphocytes in esophageal squamous cell carcinoma (ESCC) patients is highly associated with aberrant production of miR-21. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz268.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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P4592Total arterial revascularization in severe coronary artery disease: a 25-years single-center experience. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Objective
To evaluate very long-term survival of Total Arterial Revascularization (TAR) in patients with severe coronary artery disease (CAD) undergoing Coronary Artery Bypass Grafting (CABG).
Methods
Between January 1992 and December 2017, 13798 patients aged 70 years or less underwent primary isolated CABG with at least two grafts in our department. Patients receiving TAR were matched by propensity-score analysis to the rest of the population. All pre- and peri-operative data were collected prospectively in our institutional database. Long-term survival was assessed using provincial vital statistics data. The primary outcome was very-long time survival, secondary outcomes were operative mortality and early complications.
Results
Propensity-score matching identified 602 pairs with similar preoperative characteristics. In the matched control group, 65.4% and 30.9% of patients received 1 and 2 arterial grafts, respectively, whereas 3 or more arterial grafts were used in 3.6%. Less distal anastomoses (2.57±0.77 vs 3.39±0.97, p<0.0001) were performed in TAR patients, who therefore had a shorter cross-clamping time (44.2±14.7 vs 52.9±19.6, p<0.0001). Operative mortality was similar (0.5% vs 1.0%, p=0.51) and there was no difference in the rate of mediastinitis (2.5% vs 0.8%, p=0.28)for the TAR and matched control groups, respectively. TAR patients were less likely to receive blood transfusions (34.9% vs 40.7%, p=0.04). The average follow-up was 13.4±6.7 years. Cox-adjusted survival was significantly better in patients receiving TAR compared to the matched population, up to 25 years postoperatively (HR 0.87 [0.86–0.88], p<0.0001, Figure 1).
Figure 1
Conclusion
Total arterial revascularization is not associated with increased perioperative risk of complications and provides long-term survival benefits up to 25 years postoperatively.
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Aquatic animal colors and skin temperature: Biology's selection for reducing oceanic dolphin's skin friction drag. J Therm Biol 2019; 84:292-310. [PMID: 31466767 DOI: 10.1016/j.jtherbio.2019.07.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/14/2019] [Accepted: 07/14/2019] [Indexed: 10/26/2022]
Abstract
There is currently a growing interest in the area of drag reduction. In this work, the thermal effects of body color of some species of aquatics like Orcas and Dusky dolphins are investigated with respect to their swimming routes and geometric and behavioral characteristics. Considering the marine and atmospheric characteristics of these aquatics' routes, a thermal analysis is performed. The surrounding fluxes including the water flux, sun irradiation, and core temperature are considered in an energy balance to determine the skin temperature of the top side of the animal/organism's body. To study the effects of color on the surface temperature of the aquatic species, an experiment is carried out in the water on a flat plate with black and white color. Applying a turbulent analytical solution for heated boundary layers, it will be shown that the black color on the top of the bodies of these marine organisms is very efficient in terms of skin drag reduction. Moreover, to investigate the effects of the temperature on underwater skin friction drag reduction, the turbulent flow is simulated around a flat plate and a 2- dimensional modeled Killer whale at different temperatures. The results show that the top black body color of Orca and Dusky dolphin decreases their skin friction drag by 7%. This study will also provide the reason for this evolution of color scheme of other extremely fast marine animals, such as billfish, whales, and sharks. This method of drag reduction can be considered as one of the effective factors in skin drag reduction of underwater robots.
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Modelling current and future potential distributions of two desert jerboas under climate change in Iran. ECOL INFORM 2019. [DOI: 10.1016/j.ecoinf.2019.04.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Identification of chemical compositions in some medicinal plants by GC/MS analysis. LEBANESE SCIENCE JOURNAL 2019. [DOI: 10.22453/lsj-020.1.161-172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Medicinal plantsused in treatment of diseases earlier times, are potential sources of new drugs. In this study, chemical compositions of Echium khuzestanicum, Marrubium anisodan and Echinops cephalotes were identified by Gas Chromatography-Mass Spectrometry(GC/MS).M.anisodanand E.cephalotes aerial organs and E.khuzistanicum flowers were extracted by maceration method. According to the results, 46 kinds of chemical compounds found in methanol extract of E.khuzestanicum. There are mucilage, fatty acids, flavonoid and diterpenes in the flower of E.khuzestanicum. Seventy sixkinds of chemical compounds were found in methanol extract of E.cephalotesincludingaldehydes (7.9%), phenols (7.5%), fatty acids (5.8%) and furfural (5.4%)and86 kinds of chemical compounds found in M.anisodan extract. Furfural, steroids, vitamin B and flavonoids are the main compounds of M.anisodan.
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Habitat modeling of the common pheasant Phasianus colchicus (Galliformes: Phasianidae) in a highly modified landscape: application of species distribution models in the study of a poorly documented bird in Iran. EUROPEAN ZOOLOGICAL JOURNAL 2018. [DOI: 10.1080/24750263.2018.1510994] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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The Prevalence of Depression and its Associated Demographic Factors in the Elderly with Electronic Health Records in Zanjan. PREVENTIVE CARE IN NURSING AND MIDWIFERY JOURNAL 2018. [DOI: 10.29252/pcnm.8.2.18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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Meta-analysis of the prognostic role of perioperative platelet count in posthepatectomy liver failure and mortality. Br J Surg 2018; 105:1254-1261. [PMID: 29999190 DOI: 10.1002/bjs.10906] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 12/11/2022]
Abstract
BACKGROUND Emerging evidence suggests that the perioperative platelet count (PLT) can predict posthepatectomy liver failure (PHLF). In this systematic review and meta-analysis, the impact of perioperative PLT on PHLF and mortality was evaluated. METHODS MEDLINE and Web of Science databases were searched systematically for relevant literature up to January 2018. All studies comparing PHLF or mortality in patients with a low versus high perioperative PLT were included. Study quality was assessed using methodological index for non-randomized studies (MINORS) criteria. Meta-analyses were performed using Mantel-Haenszel tests with a random-effects model, and presented as odds ratios (ORs) with 95 per cent confidence intervals. RESULTS Thirteen studies containing 5260 patients were included in the meta-analysis. Two different cut-off values for PLT were used: 150 and 100/nl. Patients with a perioperative PLT below 150/nl had higher PHLF (4 studies, 817 patients; OR 4·79, 95 per cent c.i. 2·89 to 7·94) and mortality (4 studies, 3307 patients; OR 3·78, 1·48 to 9·62) rates than patients with a perioperative PLT of 150/nl or more. Similarly, patients with a PLT below 100/nl had a significantly higher risk of PHLF (4 studies, 949 patients; OR 4·65, 2·60 to 8·31) and higher mortality rates (7 studies, 3487 patients; OR 6·35, 2·99 to 13·47) than patients with a PLT of 100/nl or greater. CONCLUSION A low perioperative PLT correlates with higher PHLF and mortality rates after hepatectomy.
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Benchmarking of Siemens Linac in Electron Modes: 8-14 MeV Electron Beams. J Biomed Phys Eng 2018; 8:157-166. [PMID: 29951442 PMCID: PMC6015647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 07/27/2017] [Indexed: 11/23/2022]
Abstract
BACKGROUND Radiation therapy using electron beams is a promising method due to its physical dose distribution. Monte Carlo (MC) code is the best and most accurate technique for forespeaking the distribution of dose in radiation treatment of patients. MATERIAL AND METHODS We report an MC simulation of a linac head and depth dose on central axis, along with profile calculations. The purpose of the present research is to carefully analyze the application of MC methods for the calculation of dosimetric parameters for electron beams with energies of 8-14 MeV at a Siemens Primus linac. The principal components of the linac head were simulated using MCNPX code for different applicators. RESULTS The consequences of measurements and simulations revealed a good agreement. Gamma index values were below 1 for most points, for all energy values and all applicators in percent depth dose and dose profile computations. A number of states exhibited rather large gamma indices; these points were located at the tail of the percent depth dose graph; these points were less used in in radiotherapy. In the dose profile graph, gamma indices of most parts were below 1. The discrepancies between the simulation results and measurements in terms of Zmax, R90, R80 and R50 were insignificant. The results of Monte Carlo simulations showed a good agreement with the measurements. CONCLUSION The software can be used for simulating electron modes of a Siemens Primus linac when direct experimental measurements are not feasible.
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1.11-P8Afghan mothers with near-miss morbidity face disparity in obstetric care at university hospitals in Tehran, Iran. Eur J Public Health 2018. [DOI: 10.1093/eurpub/cky048.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Parametric optimization of daylight and thermal performance through louvers in hot and dry climate of Tehran. JOURNAL OF FUNDAMENTAL AND APPLIED SCIENCES 2018. [DOI: 10.4314/jfas.v8i3.32] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Immunomodulation in systemic lupus erythematosus: induction of M2 population in monocyte-derived macrophages by pioglitazone. Lupus 2017; 26:1318-1327. [PMID: 28457196 DOI: 10.1177/0961203317701842] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Macrophages have recently gained attention in systemic lupus erythematosus (SLE) pathogenesis for their role in the anti-inflammatory clearance of apoptotic cells. The M1/M2 polarization of macrophages improves efferocytic capability. Peroxisome proliferator-activated receptor γ is proposed to function in the expansion of the M2 subpopulation. Pioglitazone is a peroxisome proliferator-activated receptor γ agonist with a variety of anti-inflammatory effects. In this paper, we investigated the ex vivo alterations of monocyte-derived macrophages of 15 newly diagnosed SLE patients and 10 normal subjects triggered by apoptotic cells among SLE patients following pioglitazone treatment. The phagocytosis capacity of macrophages and M1/M2 polarization (CD86/CD163) was evaluated. The supernatants were also analyzed for the expression of interleukin (IL)-10, IL-12, transforming growth factor β1 and TNF-α. The mRNA expression of IL-1β and mannose receptor C-type 1 were also quantified among treated and non-treated monocyte-derived macrophages. We found that efferocytosis is defective among monocyte-derived macrophages of SLE patients and might be a major underlying mechanism involved in the sustained inflammation. Pioglitazone could enhance alternative activation of monocyte-derived macrophages and consequently immunomodulation in these patients.
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WHAT IS THE PROSTHESIS TYPE OF CHOICE DURING MITRAL VALVE REPLACEMENT FOR SEVERE ISCHEMIC MITRAL REGURGITATION? Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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INCIDENCE, PREDICTORS, AND IMPACT OF BIOPROSTHETIC VALVE HEMODYNAMIC DETERIORATION FOLLOWING AORTIC VALVE REPLACEMENT. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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TRANSCAROTID TRANSCATHETER AORTIC VALVE REPLACEMENT: WORK IN PROGRESS. Can J Cardiol 2017. [DOI: 10.1016/j.cjca.2017.07.173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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An odd very early marjolin's ulcer after minimal hand burn. ANNALS OF BURNS AND FIRE DISASTERS 2017; 30:218-219. [PMID: 29849527 PMCID: PMC5946743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 08/13/2017] [Indexed: 06/08/2023]
Abstract
Marjolin's ulcer refers to any malignant transformation of chronic wounds. Different chronic wounds may be transformed into malignancies, although they usually have a latency period of between 25 to 40 years after the primary injury. We herein present an otherwise healthy man who developed squamous cell carcinoma (SCC) three weeks after burn injury. It is an interesting case because of this acute transformation into SCC, and may be considered as different to the usual presentation of Marjolin's ulcers.
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[Computational neuroanatomy and microstructure imaging using magnetic resonance imaging]. DER NERVENARZT 2017; 88:839-849. [PMID: 28721539 DOI: 10.1007/s00115-017-0373-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Current computational neuroanatomy focuses on morphological measurements of the brain using standard magnetic resonance imaging (MRI) techniques. In comparison quantitative MRI (qMRI) typically provides a better tissue contrast and also greatly improves the sensitivity and specificity with respect to the microstructural characteristics of tissue. OBJECTIVE Current methodological developments in qMRI are presented, which go beyond morphology because this provides standardized measurements of the microstructure of the brain. The concept of in-vivo histology is introduced, based on biophysical modelling of qMRI data (hMRI) for determination of quantitative histology-like markers of the microstructure. RESULTS The qMRI metrics can be used as direct biomarkers of the microstructural mechanisms driving observed morphological findings. The hMRI metrics utilize biophysical models of the MRI signal in order to determine 3‑dimensional maps of histology-like measurements in the white matter. CONCLUSION Non-invasive brain tissue characterization using qMRI or hMRI has significant implications for both scientific and clinical applications. Both approaches improve the comparability across sites and time points, facilitate multicenter and longitudinal studies as well as standardized diagnostics. The hMRI is expected to shed new light on the relationship between brain microstructure, function and behavior both in health and disease. In the future hMRI will play an indispensable role in the field of computational neuroanatomy.
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