Machine learning decision tree models for multiclass classification of common malignant brain tumors using perfusion and spectroscopy MRI data

Background

To investigate the contribution of machine learning decision tree models applied to perfusion and spectroscopy MRI for multiclass classification of lymphomas, glioblastomas, and metastases, and then to bring out the underlying key pathophysiological processes involved in the hierarchization of the decision-making algorithms of the models.

Methods

From 2013 to 2020, 180 consecutive patients with histopathologically proved lymphomas (n = 77), glioblastomas (n = 45), and metastases (n = 58) were included in machine learning analysis after undergoing MRI. The perfusion parameters (rCBVmax, PSRmax) and spectroscopic concentration ratios (lac/Cr, Cho/NAA, Cho/Cr, and lip/Cr) were applied to construct Classification and Regression Tree (CART) models for multiclass classification of these brain tumors. A 5-fold random cross validation was performed on the dataset.

Results

The decision tree model thus constructed successfully classified all 3 tumor types with a performance (AUC) of 0.98 for PCNSLs, 0.98 for GBM and 1.00 for METs. The model accuracy was 0.96 with a RSquare of 0.887. Five rules of classifier combinations were extracted with a predicted probability from 0.907 to 0.989 for that end nodes of the decision tree for tumor multiclass classification. In hierarchical order of importance, the root node (Cho/NAA) in the decision tree algorithm was primarily based on the proliferative, infiltrative, and neuronal destructive characteristics of the tumor, the internal node (PSRmax), on tumor tissue capillary permeability characteristics, and the end node (Lac/Cr or Cho/Cr), on tumor energy glycolytic (Warburg effect), or on membrane lipid tumor metabolism.

Conclusion

Our study shows potential implementation of machine learning decision tree model algorithms based on a hierarchical, convenient, and personalized use of perfusion and spectroscopy MRI data for multiclass classification of these brain tumors.

WNT/β-catenin pathway and circadian rhythms in obsessive-compulsive disorder

The neuropsychiatric disease named obsessive-compulsive disorder is composed by obsessions and/or compulsions. Obsessive-compulsive disorder etiologies are undefined. However, numerous mechanisms in several localizations are implicated. Some studies showed that both glutamate, inflammatory factors and oxidative stress could have main functions in obsessive-compulsive disorder. Glycogen synthase kinase-3β, the major negative controller of the WNT/β-catenin pathway is upregulated in obsessive-compulsive disorder. In obsessive-compulsive disorder, some studies presented the actions of the different circadian clock genes. WNT/β-catenin pathway and circadian clock genes appear to be intricate. Thus, this review focuses on the interaction between circadian clock genes and the WNT/β-catenin pathway in obsessive-compulsive disorder.

The Key Role of the WNT/β-Catenin Pathway in Metabolic Reprogramming in Cancers under Normoxic Conditions

Simple Summary

The canonical WNT/β-catenin pathway is upregulated in cancers and plays a major role in proliferation, invasion, apoptosis and angiogenesis. Recent studies have shown that cancer processes are involved under normoxic conditions. These findings completely change the way of approaching the study of the cancer process. In this review, we focus on the fact that, under normoxic conditions, the overstimulation of the WNT/β-catenin pathway leads to modifications in the tumor micro-environment and the activation of the Warburg effect, i.e., aerobic glycolysis, autophagy and glutaminolysis, which in turn participate in tumor growth.

Abstract

The canonical WNT/β-catenin pathway is upregulated in cancers and plays a major role in proliferation, invasion, apoptosis and angiogenesis. Nuclear β-catenin accumulation is associated with cancer. Hypoxic mechanisms lead to the activation of the hypoxia-inducible factor (HIF)-1α, promoting glycolytic and energetic metabolism and angiogenesis. However, HIF-1α is degraded by the HIF prolyl hydroxylase under normoxia, conditions under which the WNT/β-catenin pathway can activate HIF-1α. This review is therefore focused on the interaction between the upregulated WNT/β-catenin pathway and the metabolic processes underlying cancer mechanisms under normoxic conditions. The WNT pathway stimulates the PI3K/Akt pathway, the STAT3 pathway and the transduction of WNT/β-catenin target genes (such as c-Myc) to activate HIF-1α activity in a hypoxia-independent manner. In cancers, stimulation of the WNT/β-catenin pathway induces many glycolytic enzymes, which in turn induce metabolic reprogramming, known as the Warburg effect or aerobic glycolysis, leading to lactate overproduction. The activation of the Wnt/β-catenin pathway induces gene transactivation via WNT target genes, c-Myc and cyclin D1, or via HIF-1α. This in turn encodes aerobic glycolysis enzymes, including glucose transporter, hexokinase 2, pyruvate kinase M2, pyruvate dehydrogenase kinase 1 and lactate dehydrogenase-A, leading to lactate production. The increase in lactate production is associated with modifications to the tumor microenvironment and tumor growth under normoxic conditions. Moreover, increased lactate production is associated with overexpression of VEGF, a key inducer of angiogenesis. Thus, under normoxic conditions, overstimulation of the WNT/β-catenin pathway leads to modifications of the tumor microenvironment and activation of the Warburg effect, autophagy and glutaminolysis, which in turn participate in tumor growth.

PPARγ Agonists: Emergent Therapy in Endometriosis

Endometriosis is one of the major gynecological diseases of reproductive-age women. This disease is characterized by the presence of glands and stroma outside the uterine cavity. Several studies have shown the major role of inflammation, angiogenesis, adhesion and invasion, and apoptosis in endometriotic lesions. Nevertheless, the mechanisms underlying endometriotic mechanisms still remain unclear and therapies are not currently efficient. The introduction of new agents can be effective by improving the condition of patients. PPARγ ligands can directly modulate these pathways in endometriosis. However, data in humans remain low. Thus, the purpose of this review is to summarize the potential actions of PPARγ agonists in endometriosis by acting on inflammation, angiogenesis, invasion, adhesion, and apoptosis.

Opposed Interplay between IDH1 Mutations and the WNT/β-Catenin Pathway: Added Information for Glioma Classification

Gliomas are the main common primary intraparenchymal brain tumor in the central nervous system (CNS), with approximately 7% of the death caused by cancers. In the WHO 2016 classification, molecular dysregulations are part of the definition of particular brain tumor entities for the first time. Nevertheless, the underlying molecular mechanisms remain unclear. Several studies have shown that 75% to 80% of secondary glioblastoma (GBM) showed IDH1 mutations, whereas only 5% of primary GBM have IDH1 mutations. IDH1 mutations lead to better overall survival in gliomas patients. IDH1 mutations are associated with lower stimulation of the HIF-1α a, aerobic glycolysis and angiogenesis. The stimulation of HIF-1α and the process of angiogenesis appears to be activated only when hypoxia occurs in IDH1-mutated gliomas. In contrast, the observed upregulation of the canonical WNT/β-catenin pathway in gliomas is associated with proliferation, invasion, aggressive-ness and angiogenesis.. Molecular pathways of the malignancy process are involved in early stages of WNT/β-catenin pathway-activated-gliomas, and this even under normoxic conditions. IDH1 mutations lead to decreased activity of the WNT/β-catenin pathway and its enzymatic targets. The opposed interplay between IDH1 mutations and the canonical WNT/β-catenin pathway in gliomas could participate in better understanding of the observed evolution of different tumors and could reinforce the glioma classification.

Potential role of cannabidiol in Parkinson's disease by targeting the WNT/β-catenin pathway, oxidative stress and inflammation

Parkinson's disease (PD) is a major neurodegenerative disease (ND), presenting a progressive degeneration of the nervous system characterized by a loss of dopamine in the substantia nigra pars compacta. Recent findings have shown that oxidative stress and inflammation play key roles in the development of PD. However, therapies remain uncertain and research for new treatment is of the utmost importance. This review focuses on the potential effects of using cannabidiol (CBD) as a potential therapeutic strategy for the treatment of PD and on some of the presumed mechanisms by which CBD provides its beneficial properties. CBD medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. Activation of the WNT/β-catenin could be associated with the control of oxidative stress and inflammation. Future prospective clinical trials should focus on CBD and its multiple interactions in the treatment of PD.

Interplay of Opposing Effects of the WNT/β-Catenin Pathway and PPARγ and Implications for SARS-CoV2 Treatment

The Coronavirus disease 2019 (COVID-19), caused by the novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), has quickly reached pandemic proportions. Cytokine profiles observed in COVID-19 patients have revealed increased levels of IL-1β, IL-2, IL-6, and TNF-α and increased NF-κB pathway activity. Recent evidence has shown that the upregulation of the WNT/β-catenin pathway is associated with inflammation, resulting in a cytokine storm in ARDS (acute respire distress syndrome) and especially in COVID-19 patients. Several studies have shown that the WNT/β-catenin pathway interacts with PPARγ in an opposing interplay in numerous diseases. Furthermore, recent studies have highlighted the interesting role of PPARγ agonists as modulators of inflammatory and immunomodulatory drugs through the targeting of the cytokine storm in COVID-19 patients. SARS-CoV2 infection presents a decrease in the angiotensin-converting enzyme 2 (ACE2) associated with the upregulation of the WNT/β-catenin pathway. SARS-Cov2 may invade human organs besides the lungs through the expression of ACE2. Evidence has highlighted the fact that PPARγ agonists can increase ACE2 expression, suggesting a possible role for PPARγ agonists in the treatment of COVID-19. This review therefore focuses on the opposing interplay between the canonical WNT/β-catenin pathway and PPARγ in SARS-CoV2 infection and the potential beneficial role of PPARγ agonists in this context.

Lithium: a potential therapeutic strategy in obsessive-compulsive disorder by targeting the canonical WNT/β pathway

Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder characterized b-y recurrent and distinctive obsessions and/or compulsions. The etiologies remain unclear. Recent findings have shown that oxidative stress, inflammation, and the glutamatergic pathway play key roles in the causes of OCD. However, first-line therapies include cognitive-behavioral therapy but only 40% of the patients respond to this first-line therapy. Research for a new treatment is mandatory. This review focuses on the potential effects of lithium, as a potential therapeutic strategy, on OCD and some of the presumed mechanisms by which lithium provides its benefit properties. Lithium medication downregulates GSK-3β, the main inhibitor of the WNT/β-catenin pathway. The activation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway. Future prospective clinical trials could focus on lithium and its different and multiple interactions in OCD.

Cannabidiol and the Canonical WNT/β-Catenin Pathway in Glaucoma

Glaucoma is a progressive neurodegenerative disease which constitutes the main frequent cause of irreversible blindness. Recent findings have shown that oxidative stress, inflammation and glutamatergic pathway play key roles in the causes of glaucoma. Recent studies have shown a down regulation of the WNT/β-catenin pathway in glaucoma, associated with overactivation of the GSK-3β signaling. WNT/β-catenin pathway is mainly associated with oxidative stress, inflammation and glutamatergic pathway. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid derived from Cannabis sativa plant which possesses many therapeutic properties across a range of neuropsychiatric disorders. Since few years, CBD presents an increased interest as a possible drug in anxiolytic disorders. CBD administration is associated with increase of the WNT/β-catenin pathway and decrease of the GSK-3β activity. CBD has a lower affinity for CB1 but can act through other signaling in glaucoma, including the WNT/β-catenin pathway. CBD downregulates GSK3-β activity, an inhibitor of WNT/β-catenin pathway. Moreover, CBD was reported to suppress pro-inflammatory signaling and neuroinflammation, oxidative stress and glutamatergic pathway. Thus, this review focuses on the potential effects of cannabidiol, as a potential therapeutic strategy, on glaucoma and some of the presumed mechanisms by which this phytocannabinoid provides its possible benefit properties through the WNT/β-catenin pathway.

Altered phospholipid and high-energy phosphate metabolism in the basal ganglia and thalamus of severe obsessive compulsive patients with treatment resistance: A phosphorus 31 nuclear magnetic resonance spectroscopy study

INTRODUCTION

Cerebral metabolism in obsessive-compulsive-disorder(OCD) has been the subject of numerous studies using proton magnetic resonance spectroscopy(MRS). Despite heterogeneous results, some studies have unraveled membrane turnover and energy metabolism abnormalities in different brain regions, suggesting that alterations in these processes may contribute to the pathophysiology. So far, no authors have explored phospholipids and high-energy phosphate metabolism using ³¹P-MRS, which allows in vivo quantification of phosphorus metabolites that are considered to be related to membrane turnover and energy metabolism.

MATERIALS AND METHODS

The aim of our study was to describe and compare brain metabolic changes using ³¹P-MRS in the striatum and the thalamus, between 23 severe OCD patients and 22 healthy controls. All subject underwent a clinical examination and a same ³¹P-MRS protocol.

RESULTS

Significantly, increased concentrations of PC, PDE,PME,GPC,PME/PCr,PDE/PCr were found in patients compared to controls in the striatum and the thalamus. PCr and tATP were decreased in the striatum. Finally, significant correlations were found in the striatum and the thalamus between illness duration and some specific measured parameters.

CONCLUSION

Our results showed significant modifications of the membrane and energy metabolism in the basal ganglia of severe OCD patients and suggests a link between energetic buffer and serotonin metabolism disorder.

Parkinson's Disease: Potential Actions of Lithium by Targeting the WNT/β-Catenin Pathway, Oxidative Stress, Inflammation and Glutamatergic Pathway

Parkinson's disease (PD) is one of the major neurodegenerative diseases (ND) which presents a progressive neurodegeneration characterized by loss of dopamine in the substantia nigra pars compacta. It is well known that oxidative stress, inflammation and glutamatergic pathway play key roles in the development of PD. However, therapies remain uncertain and research for new treatment is mandatory. This review focuses on the potential effects of lithium, as a potential therapeutic strategy, on PD and some of the presumed mechanisms by which lithium provides its benefit properties. Lithium medication downregulates GSK-3beta, the main inhibitor of the WNT/β-catenin pathway. The stimulation of the WNT/β-catenin could be associated with the control of oxidative stress, inflammation, and glutamatergic pathway. Future prospective clinical trials could focus on lithium and its different and multiple interactions in PD.

Riluzole: a therapeutic strategy in Alzheimer's disease by targeting the WNT/β-catenin pathway

Alzheimer's disease (AD) is a neurodegenerative disease, where the etiology remains unclear. AD is characterized by amyloid-(Aβ) protein aggregation and neurofibrillary plaques deposits. Oxidative stress and chronic inflammation have been suggested as causes of AD. Glutamatergic pathway dysregulation is also mainly associated with AD process. In AD, the canonical WNT/β-catenin pathway is downregulated. Downregulation of WNT/β-catenin, by activation of GSK-3β-induced Aβ, and inactivation of PI3K/Akt pathway involve oxidative stress in AD. The downregulation of the WNT/β-catenin pathway decreases the activity of EAAT2, the glutamate receptors, and leads to neuronal death. In AD, oxidative stress, neuroinflammation and glutamatergic pathway operate in a vicious circle driven by the dysregulation of the WNT/β-catenin pathway. Riluzole is a glutamate modulator and used as treatment in amyotrophic lateral sclerosis. Recent findings have highlighted its use in AD and its potential increase power on the WNT pathway. Nevertheless, the mechanism by which Riluzole can operate in AD remains unclear and should be better determine. The focus of our review is to highlight the potential action of Riluzole in AD by targeting the canonical WNT/β-catenin pathway to modulate glutamatergic pathway, oxidative stress and neuroinflammation.

Circadian Rhythms in Exudative Age-Related Macular Degeneration: The Key Role of the Canonical WNT/β-Catenin Pathway

Age-related macular degeneration (AMD) is considered as the main worldwide cause of blindness in elderly adults. Exudative AMD type represents 10 to 15% of macular degeneration cases, but is the main cause of vision loss and blindness. Circadian rhythm changes are associated with aging and could further accelerate it. However, the link between circadian rhythms and exudative AMD is not fully understood. Some evidence suggests that dysregulation of circadian functions could be manifestations of diseases or could be risk factors for the development of disease in elderly adults. Biological rhythms are complex systems interacting with the environment and control several physiological pathways. Recent findings have shown that the dysregulation of circadian rhythms is correlated with exudative AMD. One of the main pathways involved in exudative AMD is the canonical WNT/β-catenin pathway. Circadian clocks have a main role in some tissues by driving the circadian expression of genes involved in physiological and metabolic functions. In exudative AMD, the increase of the canonical WNT/β-catenin pathway is enhanced by the dysregulation of circadian rhythms. Exudative AMD progression is associated with major metabolic reprogramming, initiated by aberrant WNT/β-catenin pathway, of aerobic glycolysis. This review focuses on the interest of circadian rhythm dysregulation in exudative AMD through the aberrant upregulation of the canonical WNT/β-catenin pathway.

Curcumin: a therapeutic strategy in cancers by inhibiting the canonical WNT/β-catenin pathway

Numerous studies have presented that curcumin could have a positive effect in the prevention of cancer and then in tumor therapy. Several hypotheses have highlighted that curcumin could decreases tumor growth and invasion by acting on both chronic inflammation and oxidative stress. This review focuses on the interest of use curcumin in cancer therapy by acting on the WNT/β-catenin pathway to repress chronic inflammation and oxidative stress. In the cancer process, one of the major signaling pathways involved is the WNT/β-catenin pathway, which appears to be upregulated. Curcumin administration participates to the downregulation of the WNT/β-catenin pathway and thus, through this action, in tumor growth control. Curcumin act as PPARγ agonists. The WNT/β-catenin pathway and PPARγ act in an opposed manner. Chronic inflammation, oxidative stress and circadian clock disruption are common and co-substantial pathological processes accompanying and promoting cancers. Circadian clock disruption related to the upregulation of the WNT/β-catenin pathway is involved in cancers. By stimulating PPARγ expression, curcumin can control circadian clocks through the regulation of many key circadian genes. The administration of curcumin in cancer treatment would thus appear to be an interesting therapeutic strategy, which acts through their role in regulating WNT/β-catenin pathway and PPARγ activity levels.

Targeting the Canonical WNT/β-Catenin Pathway in Cancer Treatment Using Non-Steroidal Anti-Inflammatory Drugs

Chronic inflammation and oxidative stress are common and co-substantial pathological processes accompanying and contributing to cancers. Numerous epidemiological studies have indicated that non-steroidal anti-inflammatory drugs (NSAIDs) could have a positive effect on both the prevention of cancer and tumor therapy. Numerous hypotheses have postulated that NSAIDs could slow tumor growth by acting on both chronic inflammation and oxidative stress. This review takes a closer look at these hypotheses. In the cancer process, one of the major signaling pathways involved is the WNT/β-catenin pathway, which appears to be upregulated. This pathway is closely associated with both chronic inflammation and oxidative stress in cancers. The administration of NSAIDs has been observed to help in the downregulation of the WNT/β-catenin pathway and thus in the control of tumor growth. NSAIDs act as PPARγ agonists. The WNT/β-catenin pathway and PPARγ act in opposing manners. PPARγ agonists can promote cell cycle arrest, cell differentiation, and apoptosis, and can reduce inflammation, oxidative stress, proliferation, invasion, and cell migration. In parallel, the dysregulation of circadian rhythms (CRs) contributes to cancer development through the upregulation of the canonical WNT/β-catenin pathway. By stimulating PPARγ expression, NSAIDs can control CRs through the regulation of many key circadian genes. The administration of NSAIDs in cancer treatment would thus appear to be an interesting therapeutic strategy, which acts through their role in regulating WNT/β-catenin pathway and PPARγ activity levels.

Circadian Rhythms and Energy Metabolism Reprogramming in Parkinson's Disease

Entropy rate is increased by several metabolic and thermodynamic abnormalities in neurodegenerative diseases (NDs). Changes in Gibbs energy, heat production, ionic conductance or intracellular acidity are irreversible processes impelling modifications of the entropy rate. The present review focuses on the thermodynamic implications in the reprogramming of cellular energy metabolism enabling in Parkinson's disease (PD) through the contrasting interplay of the molecular signaling pathways WNT/ β-catenin and PPARγ. In PD, WNT/β-catenin pathway is downregulated while PPARγ is upregulated. Thermodynamic behaviors of metabolic enzymes are modified by dysregulation of the canonical WNT/β-catenin pathway. Downregulation of WNT/β-catenin pathway leads to hypometabolism, oxidative stress and cell death through inactivation of glycolytic enzymes such as Glut, PKM2, PDK1, MCT-1, LDH-A but also to activation of PDH. In addition, in NDs, PPARγ is dysregulated even though it contributes to the regulation of several key circadian genes. PD processes may be considered as dissipative structures that exchange energy or matter with their environment far-from the thermodynamic equilibrium. Far-from-equilibrium thermodynamics are notions driven by circadian rhythms, which directly contribute to regulation of the molecular pathways WNT/β-catenin and PPARγ involved in the reprogramming of cellular energy metabolism enabling in Parkinson's disease.

Metabolic reprogramming in atherosclerosis: Opposed interplay between the canonical WNT/β-catenin pathway and PPARγ

Atherosclerosis, a chronic inflammatory and age-related disease, is a complex mechanism presenting a dysregulation of vessel structures. During this process, the canonical WNT/β-catenin pathway is increased whereas PPARγ is downregulated. The two systems act in an opposite manner. This paper reviews the opposing interplay of these systems and their metabolic-reprogramming pathway in atherosclerosis. Activation of the WNT/β-catenin pathway enhances the transcription of targets involved in inflammation, endothelial dysfunction, the proliferation of vascular smooth muscle cells, and vascular calcification. This complex mechanism, which is partly controlled by the WNT/β-catenin pathway, presents several metabolic dysfunctions. This phenomenon, called aerobic glycolysis (or the Warburg effect), consists of a shift in ATP production from mitochondrial oxidative phosphorylation to aerobic glycolysis, leading to the overproduction of intracellular lactate. This mechanism is partially due to the injury of mitochondrial respiration and an increase in the glycolytic pathway. In contrast, PPARγ agonists downregulate the WNT/β-catenin pathway. Therefore, the development of therapeutic targets, such as PPARγ agonists, for the treatment of atherosclerosis could be an interesting and innovative way of counteracting the canonical WNT pathway.

PPARγ agonists: potential treatment for autism spectrum disorder by inhibiting the canonical WNT/β-catenin pathway

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that is characterized by a deficit in social interactions and communication with repetitive and restrictive behavior. No curative treatments are available for ASD. Pharmacological treatments do not address the core ASD behaviors, but target comorbid symptoms. Dysregulation of the core neurodevelopmental pathways is associated with the clinical presentation of ASD, and the canonical WNT/β-catenin pathway is one of the major pathways involved. The canonical WNT/β-catenin pathway participates in the development of the central nervous system, and its dysregulation involves developmental cognitive disorders. In numerous tissues, the canonical WNT/β-catenin pathway and peroxisome proliferator-activated receptor gamma (PPARγ) act in an opposed manner. In ASD, the canonical WNT/β-catenin pathway is increased while PPARγ seems to be decreased. PPARγ agonists present a beneficial effect in treatment for ASD children through their anti-inflammatory role. Moreover, they induce the inhibition of the canonical WNT/β-catenin pathway in several pathophysiological states. We focus this review on the hypothesis of an opposed interplay between PPARγ and the canonical WNT/β-catenin pathway in ASD and the potential role of PPARγ agonists as treatment for ASD.

Vasculogenesis and angiogenesis initiation under normoxic conditions through Wnt/β-catenin pathway in gliomas

The canonical Wnt/β-catenin pathway is up-regulated in gliomas and involved in proliferation, invasion, apoptosis, vasculogenesis and angiogenesis. Nuclear β-catenin accumulation correlates with malignancy. Hypoxia activates hypoxia-inducible factor (HIF)-1α by inhibiting HIF-1α prolyl hydroxylation, which promotes glycolytic energy metabolism, vasculogenesis and angiogenesis, whereas HIF-1α is degraded by the HIF prolyl hydroxylase under normoxic conditions. We focus this review on the links between the activated Wnt/β-catenin pathway and the mechanisms underlying vasculogenesis and angiogenesis through HIF-1α under normoxic conditions in gliomas. Wnt-induced epidermal growth factor receptor/phosphatidylinositol 3-kinase (PI3K)/Akt signaling, Wnt-induced signal transducers and activators of transcription 3 (STAT3) signaling, and Wnt/β-catenin target gene transduction (c-Myc) can activate HIF-1α in a hypoxia-independent manner. The PI3K/Akt/mammalian target of rapamycin pathway activates HIF-1α through eukaryotic translation initiation factor 4E-binding protein 1 and STAT3. The β-catenin/T-cell factor 4 complex directly binds to STAT3 and activates HIF-1α, which up-regulates the Wnt/β-catenin target genes cyclin D1 and c-Myc in a positive feedback loop. Phosphorylated STAT3 by interleukin-6 or leukemia inhibitory factor activates HIF-1α even under normoxic conditions. The activation of the Wnt/β-catenin pathway induces, via the Wnt target genes c-Myc and cyclin D1 or via HIF-1α, gene transactivation encoding aerobic glycolysis enzymes, such as glucose transporter, hexokinase 2, pyruvate kinase M2, pyruvate dehydrogenase kinase 1 and lactate dehydrogenase-A, leading to lactate production, as the primary alternative of ATP, at all oxygen levels, even in normoxic conditions. Lactate released by glioma cells via the monocarboxylate lactate transporter-1 up-regulated by HIF-1α and lactate anion activates HIF-1α in normoxic endothelial cells by inhibiting HIF-1α prolyl hydroxylation and preventing HIF labeling by the von Hippel-Lindau protein. Increased lactate with acid environment and HIF-1α overexpression induce the vascular endothelial growth factor (VEGF) pathway of vasculogenesis and angiogenesis under normoxic conditions. Hypoxia and acidic pH have no synergistic effect on VEGF transcription.

Aerobic glycolysis in amyotrophic lateral sclerosis and Huntington's disease

Neurodegenerative cells are the sites of numerous metabolic and energetic abnormalities with abnormalities in energy production. Energy is the primary determinant of neuronal viability. In neurodegenerative cells, metabolic enzymes are modified by the dysregulation of the canonical WNT/β-catenin pathway. In amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD), WNT/β-catenin pathway is upregulated. We focused this review on the hypothesis of aerobic glycolysis stimulated by the upregulation of WNT/β-catenin pathway in ALS and HD. Upregulation of WNT/β-catenin pathway induces aerobic glycolysis, named Warburg effect, through activation of glucose transporter (Glut), pyruvate kinase M2 (PKM2), pyruvate dehydrogenase kinase 1 (PDK1), monocarboxylate lactate transporter 1 (MCT-1), lactate dehydrogenase kinase-A (LDH-A), and inactivation of pyruvate dehydrogenase complex (PDH). Aerobic glycolysis consists of a supply of a large part of glucose into lactate regardless of oxygen. Aerobic glycolysis is less efficient in terms of ATP production compared with oxidative phosphorylation because of the shunt of the TCA cycle. Dysregulation of energetic metabolism promotes cell death and disease progression in ALD and HD. Aerobic glycolysis regulation is an attractive mechanism for developing therapeutic interventions.

Opposite Interplay Between the Canonical WNT/β-Catenin Pathway and PPAR Gamma: A Potential Therapeutic Target in Gliomas

In gliomas, the canonical Wingless/Int (WNT)/β-catenin pathway is increased while peroxisome proliferator-activated receptor gamma (PPAR-γ) is downregulated. The two systems act in an opposite manner. This review focuses on the interplay between WNT/β-catenin signaling and PPAR-γ and their metabolic implications as potential therapeutic target in gliomas. Activation of the WNT/β-catenin pathway stimulates the transcription of genes involved in proliferation, invasion, nucleotide synthesis, tumor growth, and angiogenesis. Activation of PPAR-γ agonists inhibits various signaling pathways such as the JAK/STAT, WNT/β-catenin, and PI3K/Akt pathways, which reduces tumor growth, cell proliferation, cell invasiveness, and angiogenesis. Nonsteroidal anti-inflammatory drugs, curcumin, antipsychotic drugs, adiponectin, and sulforaphane downregulate the WNT/β-catenin pathway through the upregulation of PPAR-γ and thus appear to provide an interesting therapeutic approach for gliomas. Temozolomide (TMZ) is an antiangiogenic agent. The downstream action of this opposite interplay may explain the TMZ-resistance often reported in gliomas.

Demyelination in Multiple Sclerosis: Reprogramming Energy Metabolism and Potential PPARγ Agonist Treatment Approaches

Demyelination in multiple sclerosis (MS) cells is the site of several energy metabolic abnormalities driven by dysregulation between the opposed interplay of peroxisome proliferator-activated receptor γ (PPARγ) and WNT/β-catenin pathways. We focus our review on the opposing interactions observed in demyelinating processes in MS between the canonical WNT/β-catenin pathway and PPARγ and their reprogramming energy metabolism implications. Demyelination in MS is associated with chronic inflammation, which is itself associated with the release of cytokines by CD4⁺ Th17 cells, and downregulation of PPARγ expression leading to the upregulation of the WNT/β-catenin pathway. Upregulation of WNT/β-catenin signaling induces activation of glycolytic enzymes that modify their energy metabolic behavior. Then, in MS cells, a large portion of cytosolic pyruvate is converted into lactate. This phenomenon is called the Warburg effect, despite the availability of oxygen. The Warburg effect is the shift of an energy transfer production from mitochondrial oxidative phosphorylation to aerobic glycolysis. Lactate production is correlated with increased WNT/β-catenin signaling and demyelinating processes by inducing dysfunction of CD4⁺ T cells leading to axonal and neuronal damage. In MS, downregulation of PPARγ decreases insulin sensitivity and increases neuroinflammation. PPARγ agonists inhibit Th17 differentiation in CD4⁺ T cells and then diminish release of cytokines. In MS, abnormalities in the regulation of circadian rhythms stimulate the WNT pathway to initiate the demyelination process. Moreover, PPARγ contributes to the regulation of some key circadian genes. Thus, PPARγ agonists interfere with reprogramming energy metabolism by directly inhibiting the WNT/β-catenin pathway and circadian rhythms and could appear as promising treatments in MS due to these interactions.

Thermodynamics in Neurodegenerative Diseases: Interplay Between Canonical WNT/Beta-Catenin Pathway-PPAR Gamma, Energy Metabolism and Circadian Rhythms

Entropy production rate is increased by several metabolic and thermodynamics abnormalities in neurodegenerative diseases (NDs). Irreversible processes are quantified by changes in the entropy production rate. This review is focused on the opposing interactions observed in NDs between the canonical WNT/beta-catenin pathway and PPAR gamma and their metabolic and thermodynamic implications. In amyotrophic lateral sclerosis and Huntington's disease, WNT/beta-catenin pathway is upregulated, whereas PPAR gamma is downregulated. In Alzheimer's disease and Parkinson's disease, WNT/beta-catenin pathway is downregulated while PPAR gamma is upregulated. The dysregulation of the canonical WNT/beta-catenin pathway is responsible for the modification of thermodynamics behaviors of metabolic enzymes. Upregulation of WNT/beta-catenin pathway leads to aerobic glycolysis, named Warburg effect, through activated enzymes, such as glucose transporter (Glut), pyruvate kinase M2 (PKM2), pyruvate dehydrogenase kinase 1(PDK1), monocarboxylate lactate transporter 1 (MCT-1), lactic dehydrogenase kinase-A (LDH-A) and inactivation of pyruvate dehydrogenase complex (PDH). Downregulation of WNT/beta-catenin pathway leads to oxidative stress and cell death through inactivation of Glut, PKM2, PDK1, MCT-1, LDH-A but activation of PDH. In addition, in NDs, PPAR gamma is dysregulated, whereas it contributes to the regulation of several key circadian genes. NDs show many dysregulation in the mediation of circadian clock genes and so of circadian rhythms. Thermodynamics rhythms operate far-from-equilibrium and partly regulate interactions between WNT/beta-catenin pathway and PPAR gamma. In NDs, metabolism, thermodynamics and circadian rhythms are tightly interrelated.

Warburg effect hypothesis in autism Spectrum disorders

Autism spectrum disorder (ASD) is a neurodevelopmental disease which is characterized by a deficit in social interactions and communication with repetitive and restrictive behavior. In altered cells, metabolic enzymes are modified by the dysregulation of the canonical WNT/β-catenin pathway. In ASD, the canonical WNT/β-catenin pathway is upregulated. We focus this review on the hypothesis of Warburg effect stimulated by the overexpression of the canonical WNT/β-catenin pathway in ASD. Upregulation of WNT/β-catenin pathway induces aerobic glycolysis, named Warburg effect, through activation of glucose transporter (Glut), pyruvate kinase M2 (PKM2), pyruvate dehydrogenase kinase 1(PDK1), monocarboxylate lactate transporter 1 (MCT-1), lactate dehydrogenase kinase-A (LDH-A) and inactivation of pyruvate dehydrogenase complex (PDH). The aerobic glycolysis consists to a supply of a large part of glucose into lactate regardless of oxygen. Aerobic glycolysis is less efficient in terms of ATP production than oxidative phosphorylation because of the shunt of the TCA cycle. Dysregulation of energetic metabolism might promote cell deregulation and progression of ASD. Warburg effect regulation could be an attractive target for developing therapeutic interventions in ASD.

Thermodynamic Aspects and Reprogramming Cellular Energy Metabolism during the Fibrosis Process

Fibrosis is characterized by fibroblast proliferation and fibroblast differentiation into myofibroblasts, which generate a relaxation-free contraction mechanism associated with excessive collagen synthesis in the extracellular matrix, which promotes irreversible tissue retraction evolving towards fibrosis. From a thermodynamic point of view, the mechanisms leading to fibrosis are irreversible processes that can occur through changing the entropy production rate. The thermodynamic behaviors of metabolic enzymes involved in fibrosis are modified by the dysregulation of both transforming growth factor β (TGF-β) signaling and the canonical WNT/β-catenin pathway, leading to aerobic glycolysis, called the Warburg effect. Molecular signaling pathways leading to fibrosis are considered dissipative structures that exchange energy or matter with their environment far from the thermodynamic equilibrium. The myofibroblastic cells arise from exergonic processes by switching the core metabolism from oxidative phosphorylation to glycolysis, which generates energy and reprograms cellular energy metabolism to induce the process of myofibroblast differentiation. Circadian rhythms are far-from-equilibrium thermodynamic processes. They directly participate in regulating the TGF-β and WNT/β-catenin pathways involved in energetic dysregulation and enabling fibrosis. The present review focusses on the thermodynamic implications of the reprogramming of cellular energy metabolism, leading to fibroblast differentiation into myofibroblasts through the positive interplay between TGF-β and WNT/β-catenin pathways underlying in fibrosis.

Effects of cannabidiol interactions with Wnt/β-catenin pathway and PPARγ on oxidative stress and neuroinflammation in Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative disease, in which the primary etiology remains unknown. AD presents amyloid beta (Aβ) protein aggregation and neurofibrillary plaque deposits. AD shows oxidative stress and chronic inflammation. In AD, canonical Wingless-Int (Wnt)/β-catenin pathway is downregulated, whereas peroxisome proliferator-activated receptor γ (PPARγ) is increased. Downregulation of Wnt/β-catenin, through activation of glycogen synthase kinase-3β (GSK-3β) by Aβ, and inactivation of phosphatidylinositol 3-kinase/Akt signaling involve oxidative stress in AD. Cannabidiol (CBD) is a non-psychotomimetic phytocannabinoid from Cannabis sativa plant. In PC12 cells, Aβ-induced tau protein hyperphosphorylation is inhibited by CBD. This inhibition is associated with a downregulation of p-GSK-3β, an inhibitor of Wnt pathway. CBD may also increase Wnt/β-catenin by stimulation of PPARγ, inhibition of Aβ and ubiquitination of amyloid precursor protein. CBD attenuates oxidative stress and diminishes mitochondrial dysfunction and reactive oxygen species generation. CBD suppresses, through activation of PPARγ, pro-inflammatory signaling and may be a potential new candidate for AD therapy.

Interactions between TGF-β1, canonical WNT/β-catenin pathway and PPAR γ in radiation-induced fibrosis

Radiation therapy induces DNA damage and inflammation leading to fibrosis. Fibrosis can occur 4 to 12 months after radiation therapy. This process worsens with time and years. Radiation-induced fibrosis is characterized by fibroblasts proliferation, myofibroblast differentiation, and synthesis of collagen, proteoglycans and extracellular matrix. Myofibroblasts are non-muscle cells that can contract and relax. Myofibroblasts evolve towards irreversible retraction during fibrosis process. In this review, we discussed the interplays between transforming growth factor-β1 (TGF-β1), canonical WNT/β-catenin pathway and peroxisome proliferator-activated receptor gamma (PPAR γ) in regulating the molecular mechanisms underlying the radiation-induced fibrosis, and the potential role of PPAR γ agonists. Overexpression of TGF-β and canonical WNT/β-catenin pathway stimulate fibroblasts accumulation and myofibroblast differentiation whereas PPAR γ expression decreases due to the opposite interplay of canonical WNT/β-catenin pathway. Both TGF-β1 and canonical WNT/β-catenin pathway stimulate each other through the Smad pathway and non-Smad pathways such as phosphatidylinositol 3-kinase/serine/threonine kinase (PI3K/Akt) signaling. WNT/β-catenin pathway and PPAR γ interact in an opposite manner. PPAR γ agonists decrease β-catenin levels through activation of inhibitors of the WNT pathway such as Smad7, glycogen synthase kinase-3 (GSK-3 β) and dickkopf-related protein 1 (DKK1). PPAR γ agonists also stimulate phosphatase and tensin homolog (PTEN) expression, which decreases both TGF-β1 and PI3K/Akt pathways. PPAR γ agonists by activating Smad7 decrease Smads pathway and then TGF-β signaling leading to decrease radiation-induced fibrosis. TGF-β1 and canonical WNT/β-catenin pathway promote radiation-induced fibrosis whereas PPAR γ agonists can prevent radiation-induced fibrosis.

PPARγ agonists: Potential treatments for exudative age-related macular degeneration

Choroidal neovascularization (CNV) characterizes the progression of exudative age-related macular degeneration (AMD) with the deterioration in the central vision. Vascular inflammation, and overproduction of inflammatory cytokines, growth factors and aberrant endothelial cell migration, initiate defective blood vessel proliferation in exudative AMD. CNV formation is initiated by the interplay between inflammation, the hallmark of exudative AMD, and the activation of WNT/β-catenin pathway. Upregulation of WNT/β-catenin pathway involves activation of PI3K/Akt pathway and then the Warburg effect to produce lactate. Lactate production generates VEGF expression and then participates to the initiation of CNV in exudative AMD. WNT/β-catenin pathway and PPARγ act in an opposite manner in several diseases. We focus this review on the interplay between PPARγ and canonical WNT/β-catenin pathway and the anti-inflammatory role of PPARγ in exudative AMD. In exudative AMD, PPARγ agonists downregulate inflammation and the WNT/β-catenin pathway. PPARγ agonists can appear as promising treatment against the initiation and the progression of CNV in exudative AMD.

Aerobic Glycolysis Hypothesis Through WNT/Beta-Catenin Pathway in Exudative Age-Related Macular Degeneration

Exudative age-related macular degeneration (AMD) is characterized by molecular mechanisms responsible for the initiation of choroidal neovascularization (CNV). Inflammatory processes are associated with upregulation of the canonical WNT/beta-catenin pathway in exudative AMD. We focus this review on the link between WNT/beta-catenin pathway activation and neovascular progression in exudative AMD through activation of aerobic glycolysis for production of angiogenic factors. Increased WNT/beta-catenin pathway involves hexokinase 2 (HK2) and pyruvate kinase M2 (PKM2). WNT/beta-catenin pathway stimulates PI3K/Akt pathway and then HIF-1alpha which activates glycolytic enzymes: glucose transporter (Glut), pyruvate dehydrogenase kinase 1 (PDK1), lactate dehydrogenase A (LDH-A), and monocarboxylate lactate transporter (MCT-1). This phenomenon is called aerobic glycolysis or the Warburg effect. Consequently, phosphorylation of PDK-1 inhibits the pyruvate dehydrogenase complex (PDH). Thus, a large part of pyruvate cannot be converted into acetyl-CoA in mitochondria and only a part of acetyl-CoA can enter the tricarboxylic acid cycle. Cytosolic pyruvate is converted into lactate through the action of LDH-A. In exudative AMD, high level of cytosolic lactate is correlated with increase of VEGF expression, the angiogenic factor of CNV. Photoreceptors in retina cells can metabolize glucose through aerobic glycolysis to protect them against oxidative damage, as cancer cells do.

Thermodynamics in Gliomas: Interactions between the Canonical WNT/Beta-Catenin Pathway and PPAR Gamma

Gliomas cells are the site of numerous metabolic and thermodynamics abnormalities with an increasing entropy rate which is characteristic of irreversible processes driven by changes in Gibbs energy, heat production, intracellular acidity, membrane potential gradient, and ionic conductance. We focus our review on the opposing interactions observed in glioma between the canonical WNT/beta-catenin pathway and PPAR gamma and their metabolic and thermodynamic implications. In gliomas, WNT/beta-catenin pathway is upregulated while PPAR gamma is downregulated. Upregulation of WNT/beta-catenin signaling induces changes in key metabolic enzyme that modify their thermodynamics behavior. This leads to activation pyruvate dehydrogenase kinase 1(PDK-1) and monocarboxylate lactate transporter 1 (MCT-1). Consequently, phosphorylation of PDK-1 inhibits pyruvate dehydrogenase complex (PDH). Thus, a large part of pyruvate cannot be converted into acetyl-CoA in mitochondria and in TCA (tricarboxylic acid) cycle. This leads to aerobic glycolysis despite the availability of oxygen, named Warburg effect. Cytoplasmic pyruvate is, in major part, converted into lactate. The WNT/beta-catenin pathway induces also the transcription of genes involved in cell proliferation, cell invasiveness, nucleotide synthesis, tumor growth, and angiogenesis, such as c-Myc, cyclin D1, PDK. In addition, in gliomas cells, PPAR gamma is downregulated, leading to a decrease in insulin sensitivity and an increase in neuroinflammation. Moreover, PPAR gamma contributes to regulate some key circadian genes. Abnormalities in the regulation of circadian rhythms and dysregulation in circadian clock genes are observed in gliomas. Circadian rhythms are dissipative structures, which play a key role in far-from-equilibrium thermodynamics through their interactions with WNT/beta-catenin pathway and PPAR gamma. In gliomas, metabolism, thermodynamics, and circadian rhythms are tightly interrelated.

On a minimal model for hemodynamics and metabolism of lactate: application to low grade glioma and therapeutic strategies

WHO II low grade glioma evolves inevitably to anaplastic transformation. Magnetic resonance imaging is a good non-invasive way to watch it, by hemodynamic and metabolic modifications, thanks to multinuclear spectroscopy (1)H/(31)P. In this work we study a multi-scale minimal model of hemodynamics and metabolism applied to the study of gliomas. This mathematical analysis leads us to a fast-slow system. The control of the position of the stationary point brings to the concept of domain of viability. Starting from this system, the equations bring to light the parameters that push glioma cells out of their domain of viability. Four fundamental factors are highlighted. The first two are cerebral blood flow and the rate of lactate transport through monocarboxylate transporters, which must be reduced in order to push glioma out of its domain of viability. Another factor is the intra arterial lactate, which must be increased. The last factor is pH, indeed a decrease of intra cellular pH could interfere with glioma growth. These reflections suggest that these four parameters could lead to new therapeutic strategies for the management of low grade gliomas.

Imaging-based assessment of the mineral composition of urinary stones: an in vitro study of the combination of hounsfield unit measurement in noncontrast helical computerized tomography and the twinkling artifact in color Doppler ultrasound

We evaluated the value of combining noncontrast helical computerized tomography (NCHCT) and color Doppler ultrasound in the assessment of the composition of urinary stones. In vitro, we studied 120 stones of known composition, that separate into the five main types: 18 calcium oxalate monohydrate (COM) stones, 41 calcium oxalate dihydrate (COD) stones, 24 uric acid stones, 25 calcium phosphate stones and 12 cystine calculi. Stones were characterized in terms of their Hounsfield density (HU) in NCHCT and the presence of a twinkling artifact (TA) in color Doppler ultrasound. There were statistically significant HU differences between calcium and non-calcium stones (p < 0.001), calcium oxalate stones and calcium phosphate stones (p < 0.001) and uric acid stones and cystine calculi (p < 0.001) but not between COM and COD stones (p = 0.786). Hence, the HU was a predictive factor of the composition of all types of stones, other than for COM and COD stones within the calcium oxalate class (p > 0.05). We found that the TA does not enable differentiation between calcium and non-calcium stones (p > 0.999), calcium oxalate stones and calcium phosphate stones (p = 0.15), or uric acid stones and cystine calculi (p = 0.079). However, it did reveal a significant difference between COM and COD stones (p = 0.002). The absence of a TA is a predictive factor for the presence of COM stones (p = 0.008). Hence, the association of NCHCT and Doppler enables the accurate classification of the five types of stones in vitro.

[Multimodal magnetic resonance imaging of brain tumors]

Magnetic resonance imaging arose as a reference for diagnosis, pre-therapeutic and follow-up of brain tumors. Among parameters obtained from standard MRI (of low specificity), only volumetric growth allows prognostic information. The multiple "advanced" sequences have leaded to increase both sensitivity and specificity of brain MRI. Yet, perfusion-weighted imaging and spectroscopy provide metabolic information, and diffusion tensor imaging and cortical activation provide functional information. Characterization, grading, therapeutic management and follow-up have improved, with prognostic information.

3T MR imaging of postoperative recurrent middle ear cholesteatomas: value of periodically rotated overlapping parallel lines with enhanced reconstruction diffusion-weighted MR imaging

BACKGROUND AND PURPOSE

MR diagnostic of postoperative recurrent cholesteatomas is difficult. Our purpose was to compare multishot fast spin-echo periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) diffusion-weighted MR imaging (DWI) with array spatial sensitivity encoding technique (ASSET) single-shot echo-planar DWI and late postgadolinium T1-weighted MR imaging for the detection of postoperative recurrent middle ear cholesteatomas with a 3T imaging unit.

MATERIALS AND METHODS

Thirty-five patients with suggested postoperative recurrent middle ear cholesteatoma underwent 3T MR imaging with PROPELLER DWI, ASSET echo-planar DWI, and late postgadolinium T1-weighted MR imaging. Three radiologists (2 seniors, 1 fellow) analyzed unlabeled images for visualization of recurrence. Interobserver and intraobserver agreement was assessed by using the Cohen kappa statistic test. Sensitivity, specificity, and predictive value were assessed for the 3 observers.

RESULTS

Nineteen recurrent cholesteatomas were diagnosed. PROPELLER interobserver agreement was very good (1, 0.89, 0.89) among the 3 observers. Intraobserver agreement between PROPELLER and T1-weighted imaging was very good to moderate (0.88, 0.57, 0.58). PROPELLER DWI provided less interobserver variability than other sequences, and the best sensitivity, specificity, and predictive value.

CONCLUSIONS

On a 3T imaging unit, multishot fast spin-echo PROPELLER DWI allows an easier detection of postoperative recurrent middle ear cholesteatoma than T1-weighted imaging by reducing artifacts and by its better contrast. DWI with PROPELLER is diagnostically robust and accurate.

[Ankle and foot sprains: conventional radiography aspects]

Emergency departments frequently encounter pathology resulting from injury to the foot and ankle, with approximately 6000 case per day in France. In an ankle sprain, 85% of the lesions involve the lateral collateral ligament. Many other, much rarer, types of lesion with different therapeutic consequences can present, however. Interpretation of the initial conventional radiographs is vital to establishing the type lesion and to proposing adapted and rapid treatment. The objective of this article is to review the various osteoarticular and ligament injuries encountered in the foot and the ankle.

[Cerebral tumours: which images?]

Magnetic resonance imaging became the gold standard examination of pretherapeutic planning and post-treatment follow-up of cerebral tumours, even if computed tomography remains useful. During the last years, many new modalities of magnetic resonance examination arose, thus leading to increase its specificity. Then, spectroscopy allows better understanding of tumoural metabolism, whereas perfusion weighted imaging provides informations on its neovascularisation. Functional cortical activation imaging and diffusion tensor imaging allows delineation of tumoural extension towards eloquent areas and fiber bundles. Last, peroperative magnetic resonance imaging may lead to better control tumour resection during operation. However, while numerous and increasing the specificity of magnetic resonance examination, confrontation to pathology data remains necessary.

Percutaneous Vertebroplasty for Spinal Metastases: Complications

PURPOSE

To retrospectively evaluate complications of percutaneous vertebroplasty (PV) performed with polymethylmethacrylate cement to treat pain in patients with metastases to the spine.

MATERIALS AND METHODS

This study had institutional review board approval; patient informed consent for the review of records and images was not required. In 2 years, 117 patients (38 men [32.5%] and 79 women [67.5%]; mean age, 58.2 years) underwent 159 fluoroscopy-guided PV procedures to treat 304 vertebrae. Spinal metastases included osteolytic, osteoblastic, and mixed lesions. Complications were characterized as local or systemic. Evaluated data included immediate imaging findings (on radiographs and computed tomographic scans) and clinical findings at 30-day follow-up. Chi2 or Fisher exact testing was performed for univariate analysis of variables.

RESULTS

The primary cancers were breast cancers (45.3%), lung cancers (14.5%), myeloma (7.7%), or other cancers (32.5%). Among the 423 cement leakages identified, 332 (78.5%) were vascular and 91 (21.5%) were nonvascular. Vascular leaks were classified as venous epidural leaks, paravertebral and foraminal plexus leaks, and leaks to the vena cava, while nonvascular leaks included puncture trajectory leaks, paravertebral soft tissue leaks, and diskal leaks. Patients with nonvascular leaks were asymptomatic. Eight (6.8%) patients experienced complications, and seven of these complications were symptomatic. Among these eight patients, six (5.1%) had local complications (puncture site hematoma in two patients and radicular pain [successfully treated with nonsteroidal anti-inflammatory drugs or corticosteroids] in four patients), and two (1.7%) had systemic complications (pulmonary embolism resulting from cement migration through the vena cava). One of the latter patients died. Univariate analyses revealed a significant association between cement migration through the vena cava and pulmonary embolism (P = .001) but not between foraminal venous leakage and radicular pain (P = .123).

CONCLUSION

Despite numerous technical incidents (leaks), PV-induced complications were rare, leading to the hypothesis that systemic complications are a consequence of intravascular leakage while local complications are a consequence of cement-related irritation, compression and/or ischemia, and/or needle-induced trauma.

Unruptured intracranial aneurysms treated by three-dimensional coil embolization: evaluation of the postoperative aneurysm occlusion volume

Our purpose was to evaluate the postoperative aneurysm occlusion volume and clinical results of treating unruptured intracranial aneurysm using three-dimensional (3D) coils. Over a 2-year period 62 aneurysms (39 with a neck < or =4 mm, 23 with a neck >4 mm) in 62 patients in five participating centres were treated. The procedure consisted, firstly, of framing the aneurysm with one or more spherical 3D coils, and secondly, of filling it with two-dimensional (2D) helical coils. Anatomical and clinical results were evaluated by univariate analysis. Multivariate analysis was used to identify independent predictors of these results. For neck sizes < or =4 and >4 mm, angiographic occlusion was complete in 31 (79%) and 16 (70%) aneurysms, respectively; the mean percentage of occlusion volume was 31.4% and 29.5%, respectively, and postoperative morbidity was 3% and 4%, respectively, with no significant differences between the two groups. There were no deaths. However, occlusion volume correlated with sac size (P = 0.037) and sac-to-neck ratio <1.5 (P = 0.073), except when three or more 3D coils per aneurysm were used (P = 0.516 and P = 0.308, respectively). Occlusion volume correlated with the number of 3D coils per aneurysm (P < 0.001) and was an independent predictor of angiographic complete occlusion (P = 0.002). The use of the largest number of 3D coils per aneurysm was safe and may improve the postoperative volume and angiographic occlusion of aneurysms with a neck >4 mm, provided the sac-to-neck ratio is > or =1.5.

Selective intra-arterial chemoembolization of pelvic and spine bone metastases

The purpose of this study was to determine the effect of interventional palliative therapy by using chemoembolization on metastatic bone pain and tumor bulk in inoperable metastases where chemotherapy and radiotherapy had failed. Twenty-five patients (mean age: 59 years) underwent chemoembolization of symptomatic lytic lesions involving the spinal column (n=10), iliac bone and sacrum (n=15). The study design consisted of at least three procedures based on combined chemoembolization performed under analog-sedation. Therapeutic agents were carboplatin for selective chemotherapy and pirarubicin mixed with polyvinyl alcohol foam for chemoembolization. Fifteen of 18 (83%) patients had significant pain relief, as shown by the decrease of analgesic drug use. Mean clinical response duration was 12 months. Radiologically, ten patients were stable. A partial response was observed in four patients, while a complete response was seen in two others. Selective intra-arterial chemoembolization gives longer pain relief than embolization, compared to the literature data, probably because of partial response with local anti-cancer drugs.

Endovascular treatment of intracranial wide-necked aneurysms using three-dimensional coils: predictors of immediate anatomic and clinical results

BACKGROUND AND PURPOSE

Aneurysms with a wide neck constitute a persistent challenge for endovascular therapy with coils. Our purpose was to evaluate the immediate anatomic and clinical results of treating intracranial wide-necked aneurysms by using three-dimensional (3D) coils.

METHODS

During a 2-year period, 160 aneurysms (116 with a neck < or = 4 mm, group A; 44 with a neck > 4 mm, group B) in 157 patients in eight participating centers were consecutively treated. The procedure consisted first of framing the aneurysm with one or more 3D spherical coils and then filling it with helical coils. Results were evaluated with univariate analysis. Multivariate analysis was used to identify independent predictors of these results.

RESULTS

Angiographic occlusion was complete in 84 (72%) and 30 (68%) aneurysms in groups A and B, respectively. Mean percentage of volumic occlusion in these groups was 30.9% and 29.2%, respectively. Perioperative morbidity and mortality rates were 4%, respectively, in group A and 2%, respectively, in group B. No significant difference between the two groups was observed. However, percentage of volumic occlusion correlated with sac-to-neck ratio less than 1.5 (P =.061) and with sac size (P =.002) except when three or more 3D coils per aneurysm were used (P =.222). The better the percentage of volumic occlusion, the better the degree of angiographic occlusion (P =.004). Percentage of volumic occlusion was an independent predictor of angiographic complete occlusion (P =.001). World Federation of Neurological Surgeons subarachnoid hemorrhage scale grade 5 was an independent predictor of perioperative mortality (P =.043).

CONCLUSION

Three-dimensional coils proved to be useful for improving coil packing and angiographic and volumic occlusion of aneurysms with a neck greater than 4 mm, at the time of treatment, provided the sac-to-neck ratio was 1.5 or greater, and the largest number of 3D coils were first positioned.

In Vitro Polyvinylformaldehyde Particle Compatibility with Chemotherapeutic Drugs Used for Chemoembolization Therapy

PURPOSE

Because the effects of pirarubicin and carboplatin on the physical structure of particles made from polyvinylformaldehyde are not well known, we describe an experiment to test the in vitro polyvinylformaldehyde particle compatibility with these drugs used for chemoembolization of bone metastases.

MATERIALS AND METHODS

Polyvinylformaldehyde particles (Ultra-Drivalon) were mixed in vitro with either pirarubicin or carboplatin as experimental samples, and with distilled water as control samples, and left for 24 h at 37 degrees C. The particles used measured 150-250 microm and 600-1000 microm in diameter. Particle morphology, including appearance, overall shape, and surface characteristics were examined using a microscope equipped with a videocamera. Particle size was measured by granulometry. Qualitative and quantitative variables were analyzed using, respectively, the two-sided Fisher's exact test and the Wilcoxon signed rank test for paired values, with a significance level of 0.05.

RESULTS

No broken particles or microscopic degradations in the appearance, overall shape, or surface characteristics of any particles were observed. The particle size distribution was not significantly different between the experimental samples containing pirarubicin or carboplatin and the control sample of particles with diameters in the same range.

CONCLUSION

Particles made from polyvinylformaldehyde can be mixed with pirarubicin or carboplatin without any risk of damaging their physical properties.

In vitro study of the compatibility of tris-acryl gelatin microspheres with various chemotherapeutic agents

PURPOSE

To evaluate the in-vitro effects of chemotherapeutic agents on the physical structure of tris-acryl gelatin microspheres.

MATERIALS AND METHODS

Microspheres (Embospheres) were mixed in vitro with carboplatin, mitomycin C, 5-fluorouracil, or pirarubicin as experimental samples and with distilled water as control samples and kept for 24 hours at 37 degrees C. The microspheres used measured 100-300 micro m and 700-900 micro m in diameter. Microsphere morphology, including appearance, overall shape, smoothness of surface, and thickness of gelatin coating, was examined with use of a microscope equipped with a cold light. Microsphere dimensions including larger diameter, smaller diameter, and surface area were measured by granulometry. Microsphere geometry was evaluated by calculating a sphericity index and surface regularity index. Qualitative and quantitative variables, respectively, were analyzed with the two-sided Fisher exact test and Wilcoxon signed-rank test for paired values, with a significance level of 0.05.

RESULTS

No broken microspheres or microscopic degradations in the appearance, overall shape, smoothness of surface, or thickness of gelatin coating of any microspheres were observed. The respective distributions of large and small diameters, surface area, sphericity index, or surface regularity index of the microspheres were not significantly different between the experimental samples containing carboplatin, mitomycin C, 5-fluorouracil, or pirarubicin and the control sample of microspheres with similar diameters.

CONCLUSION

Embosphere microspheres can be mixed with carboplatin, mitomycin C, 5-fluorouracil, or pirarubicin for chemoembolization therapy without any risk of damaging their morphology, dimensions, or geometric characteristics.

Combined central retinal arterial and venous obstruction: emergency ophthalmic arterial fibrinolysis

PURPOSE

To investigate the role of urokinase selectively perfused into the ophthalmic artery as an emergency treatment for combined central retinal arterial obstruction (CRAO) and central retinal venous obstruction (CRVO).

MATERIALS AND METHODS

Over a 6-year period, 11 consecutive patients presented with recent combined CRAO and CRVO (< or =72 hours). Urokinase (300,000 IU) was selectively perfused via the femoral artery into the ophthalmic artery for 40 minutes. Evaluation criteria were Snellen visual acuity with best correction, funduscopic results, and retinal arteriovenous transit time assessed over a mean 3.5-year follow-up. Mean vision and retinal perfusion were tested by means of repeated-measures analysis of variance. The correlation between visual improvement and retinal perfusion improvement was evaluated by means of Spearman rank correlation.

RESULTS

Substantial improvement in vision and retinal perfusion was noted in seven of the 11 patients treated. Mean vision improvement was significant (P =.009) within 24-48 hours after fibrinolysis, increased until 1 month after (P =.006), then remained stable throughout the follow-up (P >.10). Visual improvement correlated with retinal perfusion improvement during the period from before fibrinolysis to 24-48 hours after (P =.028). In all patients with improved results, retinal hemorrhages transiently increased. One patient had intravitreal hemorrhage shortly after fibrinolysis.

CONCLUSION

For this uncommon clinical entity, which typically has a poor visual outcome, these results suggest that ophthalmic arterial fibrinolysis may restore retinal perfusion, which leads to rapid substantial visual improvement in many cases of combined CRAO and CRVO, without systemic complications, but it may be responsible for intravitreal hemorrhage.

Percutaneous coaxial transpedicular biopsy of vertebral body lesions during vertebroplasty

We evaluated the safety and histological results of percutaneous transpedicular biopsy in patients undergoing vertebroplasty for vertebral collapse. Over a 6 year period, we carried out biopsies in 46 patients who underwent percutaneous injection of acrylic surgical cement for 57 collapsed vertebrae, because the diagnosis was not clearly established on clinical or imaging grounds. All procedures were performed under fluoroscopic guidance via a coaxial bitranspedicular approach used for vertebroplasty. We performed a clinical examination and CT after every procedure and approximately 6 months thereafter. Biopsies contributed to in 55 (96.5%) of the 57 vertebral lesions. Biopsy material was inadequate in one case (1.7%) and one biopsy was a false-negative (1.7%). The accuracy of the histological results was 98.2%, allowing a correct diagnosis in 55 of the 56 procedures. Of the 37 lesions in 28 patients with a history of a tumour, the final diagnosis was osteoporotic collapse in 25 (67.6%), metastasis in nine (24.3%), and myeloma in three (8.1%). The final diagnosis in the 19 lesions in 17 patients without a known tumour was osteoporotic collapse in 12 (63.2%), metastasis in five (26.3%), and amyloidosis in two (10.5%), the latter in one patient. No complications were observed.

Chronic cervical radiculopathy: lateral-approach periradicular corticosteroid injection

Thirty-two patients underwent periradicular corticosteroid injections with a lateral percutaneous approach under fluoroscopic guidance, to treat 34 foci of chronic cervical radiculopathy unresponsive to medical treatment alone. The mean evolutionary trends for radicular and neck pain relief were significant at 14 days (P <.001) and at 6 months (P <.001). The procedure did not produce any complications.

[Value of local ophthalmic artery fibrinolysis in severe forms of central retinal vein occlusion]

PURPOSE

To assess the value of selective ophthalmic artery thrombolysis as a treatment for central retinal vein occlusion (CRVO) for which no alternative therapy is available.

MATERIALS AND METHODS

Patients included in this study presented with recent severe non-ischemic CRVO. Urokinase (300,000 IU) was perfused for 40 minutes into the ophthalmic artery. Visual acuity, fundoscopy and retinal arteriovenous transit time were assessed during one year of follow-up.

RESULTS

Five of the 13 patients treated experienced a marked improvement of vision (p = 0.05) and retinal perfusion within 24-48 hours, and exhibited progressive lesion regression at fundoscopy within 2-4 weeks. The clinical course of the 5 patients prior to treatment resembled that of combined central retinal artery and vein obstruction (CRAO/CRVO), which typically has a poor visual outcome. One patient relapsed 1 month after thrombolysis. No technical complications were observed.

CONCLUSION

Although there was no control group, the short period between fibrinolysis and significant visual improvement combined with marked retinal perfusion improvement, suggests that local thrombolysis is beneficial for CRVO, especially recent CRAO/CRVO.