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2.
J Orthop Translat ; 46: 65-78, 2024 May.
Article in English | MEDLINE | ID: mdl-38808263

ABSTRACT

Backgroud: Iron overload is a prevalent condition in the elderly, often associated with various degenerative diseases, including intervertebral disc degeneration (IDD). Nevertheless, the mechanisms responsible for iron ion accumulation in tissues and the mechanism that regulate iron homeostasis remain unclear. Transferrin receptor-1 (TFR1) serves as the primary cellular iron gate, playing a pivotal role in controlling intracellular iron levels, however its involvement in IDD pathogenesis and the underlying mechanism remains obscure. Methods: Firstly, IDD mice model was established to determine the iron metabolism associated proteins changes during IDD progression. Then CEP chondrocytes were isolated and treated with TBHP or pro-inflammatory cytokines to mimic pathological environment, western blotting, immunofluorescence assay and tissue staining were employed to explore the underlying mechanisms. Lastly, TfR1 siRNA and Feristatin II were employed and the degeneration of IDD was examined using micro-CT and immunohistochemical analysis. Results: We found that the IDD pathological environment, characterized by oxidative stress and pro-inflammatory cytokines, could enhance iron influx by upregulating TFR1 expression in a HIF-2α dependent manner. Excessive iron accumulation not only induces chondrocytes ferroptosis and exacerbates oxidative stress, but also triggers the innate immune response mediated by c-GAS/STING, by promoting mitochondrial damage and the release of mtDNA. The inhibition of STING through siRNA or the reduction of mtDNA replication using ethidium bromide alleviated the degeneration of CEP chondrocytes induced by iron overload. Conclusion: Our study systemically explored the role of TFR1 mediated iron homeostasis in IDD and its underlying mechanisms, implying that targeting TFR1 to maintain balanced iron homeostasis could offer a promising therapeutic approach for IDD management. The translational potential of this article: Our study demonstrated the close link between iron metabolism dysfunction and IDD, indicated that targeting TfR1 may be a novel therapeutic strategy for IDD.

3.
J Comput Assist Tomogr ; 48(2): 303-310, 2024.
Article in English | MEDLINE | ID: mdl-37654056

ABSTRACT

INTRODUCTION: In glioma patients that have undergone surgical tumor resection, the ability to reliably distinguish between pseudoprogression (PsP) and a recurrent tumor (RT) is of key clinical importance. Accordingly, this meta-analysis evaluated the utility of dynamic susceptibility contrast-enhanced perfusion-weighted imaging as a means of distinguishing between PsP and RT when analyzing patients with high-grade glioma. MATERIALS AND METHODS: The PubMed, Web of Science, and Wanfang databases were searched for relevant studies. Pooled analyses of sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) values were conducted, after which the area under the curve (AUC) for summary receiver operating characteristic curves was computed. RESULTS: This meta-analysis ultimately included 21 studies enrolling 879 patients with 888 lesions. Cerebral blood volume-associated diagnostic results were reported in 20 of the analyzed studies, and the respective pooled sensitivity, specificity, PLR, and NLR values were 86% (95% confidence interval [CI], 0.81-0.89), 83% (95% CI, 0.77-0.87), 4.94 (95% CI, 3.61-6.75), and 0.18 (95% CI, 0.13-0.23) for these 20 studies. The corresponding AUC value was 0.91 (95% CI, 0.88-0.93), and the publication bias risk was low ( P = 0.976). Cerebral blood flow-related diagnostic results were additionally reported in 6 of the analyzed studies, with respective pooled sensitivity, specificity, PLR, and NLR values of 85% (95% CI, 0.78-0.90), 85% (95% CI, 0.76-0.91), 5.54 (95% CI, 3.40-9.01), and 0.18 (95% CI, 0.12-0.26). The corresponding AUC value was 0.92 (95% CI, 0.89-0.94), and the publication bias risk was low ( P = 0.373). CONCLUSIONS: The present meta-analysis results suggest that dynamic susceptibility contrast-enhanced perfusion-weighted imaging represents an effective diagnostic approach to distinguishing between PsP and RT in high-grade glioma patients.


Subject(s)
Brain Neoplasms , Glioma , Humans , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/pathology , Sensitivity and Specificity , Glioma/diagnostic imaging , Glioma/pathology , Magnetic Resonance Angiography , Perfusion
4.
Asia Pac J Oncol Nurs ; 10(6): 100238, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37273821

ABSTRACT

This report presents a case involving a 21-year-old male patient with acute promyelocytic leukemia, where the peripherally inserted central catheter (PICC) tip location was diagnosed differently using ultrasound and computed tomography. The PICC was inserted into the left upper arm via the basilic vein. Echocardiography performed in the left lateral recumbent position suggested the PICC tip to be in the right atrium, deepest at the level of the tricuspid annulus. However, trans-catheter contrast-enhanced echocardiography, performed with a different posture involving left shoulder abduction and slight external rotation, revealed the tip to be at the cavo-atrial junction. Additionally, chest computed tomography, conducted in the supine position with raised arms, indicated the tip to be located at the upper one-third of the superior vena cava. These contradictory diagnoses can be attributed to the use of different body postures during the assessments. Considering the clinical efficacy and safety, it is crucial to fully consider the influence of multiple postures on PICC tip location during placement and determination. We recommend incorporating at least two opposite extreme daily postures to assess the nearest and farthest positions of the tip, ensuring effective and safe PICC placement and reducing the risk of complications.

5.
Chin J Physiol ; 63(5): 218-226, 2020.
Article in English | MEDLINE | ID: mdl-33109788

ABSTRACT

Cognitive impairments are associated with advancing age. Trans-cinnamaldehyde (CIN) and ellagic acid (ELA) have multiplex activities to reduce various age-related cognitive disorders. In this study, we investigated the effects of these compounds separately or in combination on the cognitive outcomes, mitochondrial function, and inflammatory and apoptotic mediators in aged male Wistar rats. Thirty-two old (22 months old) and eight young (5 months old) rats were randomly allocated to five groups of young control, aged control, ELA-aged, CIN-aged, and ELA + CIN-aged. ELA (15 mg/kg, orally) and CIN (50 mg/kg, intraperitoneally) separately or in combination were administered for 1 month in aged animals. Spatial memory and cognitive activity were evaluated by the Barnes maze and novel object recognition tests. Mitochondrial function (its reactive oxygen species [ROS], mitochondrial membrane potential and ATP level), pro-inflammatory cytokines such as interleukin (IL)-1ß and IL-6 and pro-apoptotic caspase 3 and Bax, and anti-apoptotic Bcl2 levels and their ratio were assessed in the prefrontal cortex. Behavioral results revealed that CIN separately or in combination with ELA significantly alleviates aging-induced memory impairment. Moreover, co-administration of agents effectively decreased inflammatory cytokines, cleaved-caspase 3, Bax and Bax/Bcl2 levels, mitochondrial ROS production, and mitochondrial membrane depolarization and increased Bcl2 and ATP level as compared with untreated aged control rats. Combination therapy was greater than those of individual treatments in all parameters. Therefore, combination therapy with CIN and ELA improved aging-induced cognitive impairment through anti-inflammatory, anti-apoptotic, and mitochondrial-boosting effects in aged rats.


Subject(s)
Acrolein/analogs & derivatives , Aging/pathology , Apoptosis/drug effects , Cognitive Dysfunction , Ellagic Acid/pharmacology , Mitochondria/drug effects , Acrolein/pharmacology , Animals , Anti-Inflammatory Agents/pharmacology , Cognitive Dysfunction/drug therapy , Male , Prefrontal Cortex , Rats , Rats, Wistar
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(5): 1019-24, 2011 Oct.
Article in Chinese | MEDLINE | ID: mdl-22097275

ABSTRACT

This paper is to provide a basis for the establishment of an early diagnostic system for hypoxic-ischemic encephalopathy (HIE) by performing segmentation and feature extraction of lesions on the MR images of neonatal babies with HIE. The segmentation on MR images of HIE based on the genetic algorithm (GA) combined with a pulse-coupled neural network (PCNN) were carried out. There were better segmentation results by using PCNN segmentation based on GA than PCNN segmentation with fixed parameters. The data suggested that a PCNN based on GA could provide effective assistance for diagnosis and research.


Subject(s)
Hypoxia-Ischemia, Brain/diagnosis , Image Processing, Computer-Assisted , Magnetic Resonance Imaging/methods , Neural Networks, Computer , Algorithms , Female , Humans , Hypoxia-Ischemia, Brain/physiopathology , Infant, Newborn , Male
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 28(4): 814-8, 829, 2011 Aug.
Article in Chinese | MEDLINE | ID: mdl-21936387

ABSTRACT

This paper is aimed to study a method and feasibility of early diagnostic system using hypoxic ischemic encephalopathy (HIE) in the newborns. Fifteen non-invasive indicators with high sensitivity and specificity were selected for the early diagnosis of HIE on the basis of related researches from the literature and the researches in our laboratory. The diagnostic test was done with 140 cases with the HIE, using the fussy BP neural network experiment system. The initial results showed that the accuracy rate was 100% for the training set and 95% for the testing set, and the error rate was 5%. The data suggested that the fuzzy back-propagation neural networks, with the clinical comprehensive indicators, exhibited a high accuracy for the early diagnosis of HIE. This method provides an objective and convenient new way for the early clinical diagnosis of the HIE.


Subject(s)
Fuzzy Logic , Hypoxia-Ischemia, Brain/diagnosis , Neural Networks, Computer , Pattern Recognition, Automated/methods , Algorithms , Diagnosis, Computer-Assisted/methods , Early Diagnosis , Female , Humans , Infant, Newborn , Male , Reproducibility of Results , Sensitivity and Specificity
8.
Exp Gerontol ; 44(9): 594-600, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19563877

ABSTRACT

Iron is necessary for life but also a potent pro-oxidant implicated in the pathogenesis of age-related diseases. We sought to determine if iron levels change with age and by sex in various tissues from several commonly studied mouse strains. Brain, liver, heart, retina, and retinal pigment epithelium (RPE)/choroid were dissected from male and female mice of young adult (2-6 month old) and aged (16-19 month old) C57BL/6, DBA/2J, and BALB/c mice. Iron was quantified through a chromagen-based spectrophotometric method or through atomic absorption spectrophotometry for increased sensitivity. Brain, liver, and heart iron increased by 30-70% in aged vs. young adult groups of all strains, while retina and RPE/choroid iron had variable age-related changes. Significant gender differences were observed in BALB/c and DBA/2J strains. Males had as much as 2- to 3-fold more brain, RPE/choroid, and retinal iron, while females had as much as 2- to 3-fold more liver iron. There was no significant gender difference observed in heart iron. The different profiles of change between gender and among strains suggest that hormones and genetics influence iron regulation with aging. Future manipulation of iron levels in mice will test the role of iron in aging and disease, and the data reported herein will be essential in directing such manipulations.


Subject(s)
Aging/physiology , Iron/metabolism , Oxidative Stress/physiology , Reactive Oxygen Species/metabolism , Sex Characteristics , Subcutaneous Tissue/metabolism , Analysis of Variance , Animals , Female , Iron/physiology , Male , Mice , Spectrophotometry
9.
Invest Ophthalmol Vis Sci ; 49(9): 4071-7, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18421081

ABSTRACT

PURPOSE: To study photoreceptor apoptosis and iron migration as mechanisms of retinotoxicity in a rabbit model of subretinal hemorrhage (SRH) and to assess intravitreal triamcinolone acetonide (IVTA) for anti-apoptotic and neuroprotective effects. METHODS: In adult rabbits, eyes were studied histologically after subretinal injection of autologous blood. For comparisons of control eyes with eyes injected with 2 mg IVTA, morphometric analysis was performed with light microscopy, whereas apoptosis was quantified with terminal dUTP nick end labeling (TUNEL) and fluorescence microscopy. Localization of retinal iron was assessed with Perls' stain. RESULTS: Photoreceptor degeneration was initiated 48 hours after exposure to subretinal blood and progressed over 7 days. Increased TUNEL positivity demonstrating apoptotic cell death was associated with SRH and photoreceptor loss. VIP-Perls staining demonstrated iron in the photoreceptor layer and retinal pigment epithelium that correlated with photoreceptor degeneration. Treatment with IVTA enhanced photoreceptor cell survival by 11% at 48 hours and by 45% at 72 hours (P = 0.01) and reduced photoreceptor apoptosis ratios by 25% at 48 hours (P = 0.006). CONCLUSIONS: Photoreceptor toxicity caused by SRH occurs at least in part by apoptosis and is associated with iron migration to the photoreceptor layer. Treatment with IVTA reduced photoreceptor loss and apoptosis, indicating a neuroprotective action. Therapies to target SRH may augment anti-VEGF treatments in exudative age-related macular degeneration and other diseases of choroidal neovascularization.


Subject(s)
Apoptosis/drug effects , Neuroprotective Agents/therapeutic use , Photoreceptor Cells/physiopathology , Retinal Hemorrhage/drug therapy , Triamcinolone Acetonide/therapeutic use , Vitreous Body/physiopathology , Animals , Disease Models, Animal , Female , Iron/metabolism , Neuroprotective Agents/administration & dosage , Photoreceptor Cells/drug effects , Photoreceptor Cells/pathology , Propoxycaine/pharmacology , Pupil/drug effects , Pupil/physiology , Rabbits , Retinal Hemorrhage/pathology , Retinal Hemorrhage/physiopathology , Triamcinolone Acetonide/administration & dosage , Vitreous Body/drug effects
10.
Invest Ophthalmol Vis Sci ; 49(6): 2728-36, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18326691

ABSTRACT

PURPOSE: Iron is an essential element in human metabolism but also is a potent generator of oxidative damage with levels that increase with age. Several studies suggest that iron accumulation may be a factor in age-related macular degeneration (AMD). In prior studies, both iron overload and features of AMD were identified in mice deficient in the ferroxidase ceruloplasmin (Cp) and its homologue hephaestin (Heph) (double knockout, DKO). In this study, the location and timing of iron accumulation, the rate and reproducibility of retinal degeneration, and the roles of oxidative stress and complement activation were determined. METHODS: Morphologic analysis and histochemical iron detection by Perls' staining was performed on retina sections from DKO and control mice. Immunofluorescence and immunohistochemistry were performed with antibodies detecting activated complement factor C3, transferrin receptor, L-ferritin, and macrophages. Tissue iron levels were measured by atomic absorption spectrophotometry. Isoprostane F2alpha-VI, a specific marker of oxidative stress, was quantified in the tissue by gas chromatography/mass spectrometry. RESULTS: DKOs exhibited highly reproducible age-dependent iron overload, which plateaued at 6 months of age, with subsequent progressive retinal degeneration continuing to at least 12 months. The degeneration shared some features of AMD, including RPE hypertrophy and hyperplasia, photoreceptor degeneration, subretinal neovascularization, RPE lipofuscin accumulation, oxidative stress, and complement activation. CONCLUSIONS: DKOs have age-dependent iron accumulation followed by retinal degeneration modeling some of the morphologic and molecular features of AMD. Therefore, these mice are a good platform on which to test therapeutic agents for AMD, such as antioxidants, iron chelators, and antiangiogenic agents.


Subject(s)
Ceruloplasmin/physiology , Disease Models, Animal , Iron Overload/pathology , Macular Degeneration/pathology , Membrane Proteins/physiology , Animals , Apoferritins/metabolism , Choroid/metabolism , Complement Activation , Complement C3/metabolism , Complement Factor B/metabolism , Dinoprost/analogs & derivatives , Dinoprost/metabolism , Gas Chromatography-Mass Spectrometry , Iron/metabolism , Iron Overload/metabolism , Macrophages/pathology , Macular Degeneration/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Oxidative Stress , Pigment Epithelium of Eye/metabolism , Receptors, Transferrin/metabolism , Retina/metabolism , Spectrophotometry, Atomic
11.
Prog Retin Eye Res ; 26(6): 649-73, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17921041

ABSTRACT

Iron is essential for many metabolic processes but can also cause damage. As a potent generator of hydroxyl radical, the most reactive of the free radicals, iron can cause considerable oxidative stress. Since iron is absorbed through diet but not excreted except through menstruation, total body iron levels buildup with age. Macular iron levels increase with age, in both men and women. This iron has the potential to contribute to retinal degeneration. Here we present an overview of the evidence suggesting that iron may contribute to retinal degenerations. Intraocular iron foreign bodies cause retinal degeneration. Retinal iron buildup resulting from hereditary iron homeostasis disorders aceruloplasminemia, Friedreich's ataxia, and panthothenate kinase-associated neurodegeneration cause retinal degeneration. Mice with targeted mutation of the iron exporter ceruloplasmin have age-dependent retinal iron overload and a resulting retinal degeneration with features of age-related macular degeneration (AMD). Post mortem retinas from patients with AMD have more iron and the iron carrier transferrin than age-matched controls. Over the past 10 years much has been learned about the intricate network of proteins involved in iron handling. Many of these, including transferrin, transferrin receptor, divalent metal transporter-1, ferritin, ferroportin, ceruloplasmin, hephaestin, iron-regulatory protein, and histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis (HFE) have been found in the retina. Some of these proteins have been found in the cornea and lens as well. Levels of the iron carrier transferrin are high in the aqueous and vitreous humors. The functions of these proteins in other tissues, combined with studies on cultured ocular tissues, genetically engineered mice, and eye exams on patients with hereditary iron diseases provide clues regarding their ocular functions. Iron may play a role in a broad range of ocular diseases, including glaucoma, cataract, AMD, and conditions causing intraocular hemorrhage. While iron deficiency must be prevented, the therapeutic potential of limiting iron-induced ocular oxidative damage is high. Systemic, local, or topical iron chelation with an expanding repertoire of drugs has clinical potential.


Subject(s)
Homeostasis , Iron/metabolism , Iron/poisoning , Retinal Degeneration/chemically induced , Retinal Degeneration/metabolism , Animals , Biological Transport , Epithelial Cells/metabolism , Humans , Lens, Crystalline/metabolism , Oxidative Stress , Retina/metabolism
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