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BACKGROUND: Neuroinflammation is one of the most important pathogeneses in secondary brain injury after traumatic brain injury (TBI). Neutrophil extracellular traps (NETs) forming neutrophils were found throughout the brain tissue of TBI patients and elevated plasma NET biomarkers correlated with worse outcomes. However, the biological function and underlying mechanisms of NETs in TBI-induced neural damage are not yet fully understood. Here, we used Cl-amidine, a selective inhibitor of NETs to investigate the role of NETs in neural damage after TBI. METHODS: Controlled cortical impact model was performed to establish TBI. Cl-amidine, 2'3'-cGAMP (an activator of stimulating Interferon genes (STING)), C-176 (a selective STING inhibitor), and Kira6 [a selectively phosphorylated inositol-requiring enzyme-1 alpha [IRE1α] inhibitor] were administrated to explore the mechanism by which NETs promote neuroinflammation and neuronal apoptosis after TBI. Peptidyl arginine deiminase 4 (PAD4), an essential enzyme for neutrophil extracellular trap formation, is overexpressed with adenoviruses in the cortex of mice 1 day before TBI. The short-term neurobehavior tests, magnetic resonance imaging (MRI), laser speckle contrast imaging (LSCI), Evans blue extravasation assay, Fluoro-Jade C (FJC), TUNEL, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), western blotting, and quantitative-PCR were performed in this study. RESULTS: Neutrophils form NETs presenting in the circulation and brain at 3 days after TBI. NETs inhibitor Cl-amidine treatment improved short-term neurological functions, reduced cerebral lesion volume, reduced brain edema, and restored cerebral blood flow (CBF) after TBI. In addition, Cl-amidine exerted neuroprotective effects by attenuating BBB disruption, inhibiting immune cell infiltration, and alleviating neuronal death after TBI. Moreover, Cl-amidine treatment inhibited microglia/macrophage pro-inflammatory polarization and promoted anti-inflammatory polarization at 3 days after TBI. Mechanistically, STING ligand 2'3'-cGAMP abolished the neuroprotection of Cl-amidine via IRE1α/ASK1/JNK signaling pathway after TBI. Importantly, overexpression of PAD4 promotes neuroinflammation and neuronal death via the IRE1α/ASK1/JNK signaling pathway after TBI. However, STING inhibitor C-176 or IRE1α inhibitor Kira6 effectively abolished the neurodestructive effects of PAD4 overexpression after TBI. CONCLUSION: Altogether, we are the first to demonstrate that NETs inhibition with Cl-amidine ameliorated neuroinflammation, neuronal apoptosis, and neurological deficits via STING-dependent IRE1α/ASK1/JNK signaling pathway after TBI. Thus, Cl-amidine treatment may provide a promising therapeutic approach for the early management of TBI.
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Lesiones Traumáticas del Encéfalo , Trampas Extracelulares , Humanos , Ratones , Animales , Sistema de Señalización de MAP Quinasas , Interferón-alfa/metabolismo , Enfermedades Neuroinflamatorias , Endorribonucleasas , Modelos Animales de Enfermedad , Proteínas Serina-Treonina Quinasas/metabolismo , Lesiones Traumáticas del Encéfalo/patología , Apoptosis , Ratones Endogámicos C57BLRESUMEN
OBJECTIVES: Endothelial cell-derived microparticles (EMPs) are directly indicative of endothelial cell activation or apoptosis, and may also reflect endothelial inflammation, increased coagulation, and vascular tone. The aim of this study is to investigate whether EMPs would be able to evaluate system involvement and be a new indicators of disease activity in Behçet's disease (BD). METHODS: Thirty-nine consecutive BD patients (who fulfilled the modified 1990 International Study Group on Behçet's disease or the 2006 International Criteria for Behçet's Disease) and 30 age- and sex-matched healthy controls were enrolled. The plasma levels of EMPs were measured by flow cytometry utilising specific labels for endothelial MPs (CD31+ and CD42b-). RESULTS: The levels of circulating EMPs (CD31+ and CD42b-) were significantly elevated in the case group compared with the healthy control group (p =0.000). Moreover, BD patients plasma EMPs were positively correlated with BD current activity form (r=0.802, p =0.000). Vascular and gastrointestinal involvement in BD patients were significantly increased (p=0.004 and p=0.011, respectively) with respect to patients without vascular and gastrointestinal EMPs. CONCLUSIONS: Levels of circulating EMPs are elevated in BD patients and correlate with the disease activity; the elevated EMPs may be a potential indicator to predict disease activity of BD. The plasma level of EMPs was increased, which indicated the increased risk of vascular and digestive tract involvement in BD.
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Síndrome de Behçet , Micropartículas Derivadas de Células , Humanos , Síndrome de Behçet/diagnóstico , Micropartículas Derivadas de Células/fisiología , Inflamación , Endotelio Vascular , BiomarcadoresRESUMEN
The discovery and isolation of new non-Bt insecticidal bacteria and genes are significant for the development of new biopesticides against coleopteran pests. In this study, we evaluated the insecticidal activity of non-Bt insecticidal bacteria, PPBiotE33, IPPBiotC41, IPPBiotA42 and IPPBiotC43, isolated from the peanut rhizosphere. All these strains showed insecticidal activity against first- and third-instar larvae of Holotrichia parallela, Holotrichia oblita, Anomala corpulenta and Potosia brevitarsis. IPPBiotE33 showed the highest toxicity among the four strains and exhibited virulence against Colaphellus bowringi. The genome of IPPBiotE33 was sequenced, and a new protein, 03673, with growth inhibition effects on C. bowringi was obtained. In addition, IPPBiotE33 had a synergistic effect with Bacillus thuringiensis Bt185 against H. parallela in bioassays and back-inoculation experiments with peanut seedlings. IPPBiotE33 induced a decrease in hemocytes and an increase in phenol oxidase activity in H. parallela hemolymph, known as the immunosuppressive effect, which mediated synergistic activity with Bt185. This study increased our knowledge of the new insecticidal strain IPPBiotE33 and shed new light on the research on new insecticidal coaction mechanisms and new blended pesticides.
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Pest feeding affects the rhizobacteria community. The rhizomicrobiota activates salicylic acid and jasmonic acid signaling pathways to help plants deal with pest infestation. However, whether plants can recruit special pesticidal microorganisms to deal with attack from herbivores is unclear. A system composed of peanuts and first-instar larvae of Holotrichia parallela were used to analyze whether peanuts truly enrich the insecticidal bacteria after feeding by larvae, and whether inoculation of the enriched bacteria promotes the resistance of plants to herbivore. In this study, high-throughput sequencing of 16 S rRNA gene amplicons was used to demonstrate that infestation of the subterranean pest H. parallela quickly changed the rhizosphere bacterial community structure within 24 h, and the abundance of Enterobacteriaceae, especially Enterobacter, was manifestly enriched. Root feeding induced rhizobacteria to form a more complex co-occurrence network than the control. Rhizosphere bacteria were isolated, and 4 isolates with high toxicity against H. parallela larvae were obtained by random forest analysis. In a back-inoculation experiment using a split-root system, green fluorescent protein (GFP)-labeled Enterobacter sp. IPPBiotE33 was observed to be enriched in uneaten peanut roots. Additionally, supplementation with IPPBiotE33 alleviated the adverse effects of H. parallela on peanuts. Our findings indicated that herbivore infestation could induce plants to assemble bacteria with specific larvicidal activity to address threats.
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Escarabajos , Insecticidas , Animales , Herbivoria , Insecticidas/farmacología , Insecticidas/metabolismo , Escarabajos/microbiología , Larva , Bacterias/genética , Plantas , Raíces de Plantas/microbiologíaRESUMEN
Objectives: Patients with traumatic brain injury (TBI) often suffer memory and cognitive impairments, and oxiracetam-like drugs are considered to have a positive impact on these symptoms potentially. However, the efficacy and safety of l-oxiracetam and oxiracetam in TBI patients have not been sufficiently investigated. Methods: The study adopts a multicenter, randomized, double-blind, parallel-group, phase 3 clinical trial design in 74 centers across 51 hospitals in China. A total of 590 TBI patients meeting criteria will be randomly allocated into three groups in a 2:2:1 ratio: l-oxiracetam group, oxiracetam group, and placebo group. The treatment period is 14 days, with a follow-up period of 90 days. The primary outcome measure is the change in the Loewenstein Occupational Therapy Cognitive Assessment score at 90 days after treatment. Secondary outcomes include changes in other cognitive assessments, neurological function, activities of daily living, and safety assessments. Discussion: There is no robust evidence to suggest that l-oxiracetam and oxiracetam can enhance memory and cognitive function in patients with mild to moderate TBI. This study has the potential to answer this crucial clinical question. Trial registration: chinadrugtrials.org.cn, identifier CTR20192539; ClinicalTrials.gov, identifier NCT04205565.
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BACKGROUND: Despite its prevalence, there is ongoing debate regarding the optimal management strategy for chronic subdural hematoma (CSDH), reflecting the variability in clinical presentation and treatment outcomes. This ambidirectional, nationwide, multicenter registry study aims to assess the efficacy and safety of multimodality treatment approaches for CSDH in the Chinese population. METHODS/DESIGN: A multicenter cohort of CSDH patients from 59 participating hospitals in mainland China was enrolled in this study. The treatment modalities encompassed a range of options and baseline demographics, clinical characteristics, radiographic findings, and surgical techniques were documented. Clinical outcomes, including hematoma resolution, recurrence rates, neurological status, and complications, were assessed at regular intervals during treatment, 3 months, 6 months, 1 year, and 2 years follow-up. RESULT: Between March 2022 and August 2023, a comprehensive cohort comprising 2173 individuals who met the criterion was assembled across 59 participating clinical sites. Of those patients, 81.1% were male, exhibiting an average age of 70.12 ± 14.53 years. A historical record of trauma was documented in 48.0% of cases, while headache constituted the predominant clinical presentation in 58.1% of patients. The foremost surgical modality employed was the burr hole (61.3%), with conservative management accounting for 25.6% of cases. Notably, a favorable clinical prognosis was observed in 88.9% of CSDH patients at 3 months, and the recurrence rate was found to be 2.4%. CONCLUSION: This registry study provides critical insights into the multimodality treatment of CSDH in China, offering a foundation for advancing clinical practices, optimizing patient management, and ultimately, improving the quality of life for individuals suffering from this challenging neurosurgical condition. TRIAL REGISTRATION: ChiCTR2200057179.
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A convergent, enantiocontrolled total synthesis of the 15-membered macrolide, amphidinolide P, is described. The synthesis utilizes three nonracemic components for an efficient assembly of the macrolactone in 12 steps via the longest linear pathway. Key developments include studies of the Hosomi-Sakurai reaction for the formation of the C6-C7 bond, a "ligandless" palladium-mediated Stille cross-coupling of the vinylic stannane 4 and the alkenyl bromide 5 to produce a highly functionalized dienol, and a thermally induced, intramolecular lactonization via the late-stage formation of an intermediate α-acylketene.
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Macrólidos/síntesis química , Macrólidos/química , Conformación MolecularRESUMEN
Endoplasmic reticulum (ER) stress and ER stress-mediated apoptosis play an important role during secondary brain damage after traumatic brain injury (TBI). Increased neutrophil extracellular traps (NETs) formation has been demonstrated to be associated with neurological damage after TBI. However, the correlation between ER stress and NETs remains unclear, and the specific function of NETs in neurons has not been defined. In this study, we found that the levels of NETs circulating biomarkers were remarkably elevated in the plasma of TBI patients. We then inhibited NETs formation by peptidylarginine deiminase 4 (PAD4, a critical enzyme for NETs formation) deficiency and discovered that ER stress activation and ER stress-mediated neuronal apoptosis were reduced. The degradation of NETs via DNase I showed similar outcomes. Furthermore, overexpression of PAD4 aggravated neuronal ER stress and ER stress-associated apoptosis, while TLR9 antagonist administration abrogated the damage caused by NETs. In addition to in vivo experiments, in vitro experiments revealed that treatment with a TLR9 antagonist alleviated NETs-induced ER stress and apoptosis in HT22 cells. Collectively, our results indicated that ER stress as well as the accompanying neuronal apoptosis can be ameliorated by disruption of NETs and that suppression of the TLR9-ER stress signaling pathway may contribute to positive outcomes after TBI.
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Lesiones Traumáticas del Encéfalo , Trampas Extracelulares , Humanos , Trampas Extracelulares/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Apoptosis/fisiología , Lesiones Traumáticas del Encéfalo/metabolismo , Neuronas/metabolismo , Estrés del Retículo Endoplásmico/fisiología , Neutrófilos/metabolismoRESUMEN
NOD-like receptor (NLR) family pyrin domain-containing 1 (NLRP1) is a member of the NLR family. The NLRP1 inflammasome consists of the NLRP1 protein, the adaptor protein apoptosis-associated speck-like protein containing a CARD domain, and the effector molecule pro-caspase-1. When stimulated, the inflammasome initiates the cleavage of pro-caspase-1 and converts it into its active form, caspase-1; then, caspase-1 facilitates the cleavage of the proinflammatory cytokines interleukin-1ß and interleukin-18 into their active and secreted forms. In addition, caspase-1 also mediates the cleavage of gasdermin D, which leads to pyroptosis, an inflammatory form of cell death. Pathological events that damage the brain and result in neuropathological conditions can generally be described as brain injury. Neuroinflammation, especially that driven by NLRP1, plays a considerable role in the pathophysiology of brain injury, such as early brain injury (EBI) of subarachnoid hemorrhage, ischemic brain injury during stroke, and traumatic brain injury (TBI). In this article, a thorough overview of NLRP1 is presented, including its structure, mechanism of activation, and role in neuroinflammation. We also present recent studies on NLRP1 as a target for the treatment of EBI, ischemic brain injury, TBI, and other types of brain injury, thus highlighting the perspective of NLRP1 as an effective mediator of catastrophic brain injury.
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Lesiones Traumáticas del Encéfalo , Lesiones Encefálicas , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Lesiones Encefálicas/patología , Lesiones Traumáticas del Encéfalo/terapia , Caspasa 1/metabolismo , Humanos , Inflamasomas/metabolismo , Proteínas NLR/metabolismoRESUMEN
The radial error is the key performance indicator of ultra-precision axis. In order to measure and evaluate the radial error of ultra-precision axis with nanometer accuracy, a measurement system with an accuracy of nanometer based on capacitive displacement probes and standard spheres is developed. The nonlinearity error of capacitive displacement probes, misalignment error of the probes, eccentric error of standard spheres, error caused by environment temperature change, environment vibration and error separation methods are analyzed and the effects of the above factors are obtained; Multiple measurement examples carried out with the measurement system this paaper constructed indicate the repeatability of the measurement system reaches 10.5 nm and the roundness error of artifact separated is less than 4.03 nm. In order to evaluate the measurement dispersion of the ultra-precision axis radial error, the major uncertainty components and the complete process of the comprehensive evaluation of the measurement uncertainty are proposed. The combined uncertainty of radial error motion measurement of the ultra-precision axis with Donaldson reversal is 31.64 nm (k = 2).
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Cellular homeostasis requires critical communications between the endoplasmic reticulum (ER) and mitochondria to maintain the viability of cells. This communication is mediated and maintained by the mitochondria-associated membranes and may be disrupted during acute traumatic brain injury (TBI), leading to structural and functional damage of neurons and supporting cells. To test this hypothesis, we subjected male C57BL/6 mice to severe TBI (sTBI) using a controlled cortical impact device. We analyzed the physical ER-mitochondrion contacts in the perilesional cortex using transmission electron microscopy, Western blot, and immunofluorescence. We specifically measured changes in the production of reactive oxygen species (ROS) in mitochondria, the unfolded protein response (UPR), the neuroinflammatory response, and ER stress-mediated apoptosis in the traumatic injured cerebral tissue. A modified neurological severity score was used to evaluate neurological function in the sTBI mice. We found that sTBI induced significant reorganizations of mitochondria-associated ER membranes (MAMs) in the cerebral cortex within the first 24 h post-injury. This ER-mitochondrion coupling was enhanced, reaching its peak level at 6 h post-sTBI. This enhanced coupling correlated closely with increases in the expression of the Ca2+ regulatory proteins (inositol 1,4,5-trisphosphate receptor type 1 [IP3R1], voltage-dependent anion channel 1 [VDAC1], glucose-regulated protein 75 [GRP75], Sigma 1 receptor [Sigma-1R]), production of ROS, degree of ER stress, levels of UPR, and release of proinflammatory cytokines. Further, the neurological function of sTBI mice was significantly improved by silencing the gene for the ER-mitochondrion tethering factor PACS2, restoring the IP3R1-GRP75-VDAC1 axis of Ca2+ regulation, alleviating mitochondria-derived oxidative stress, suppressing inflammatory response through the PERK/eIF2α/ATF4/CHOP pathway, and inhibiting ER stress and associated apoptosis. These results indicate that dysfunctional ER-mitochondrion coupling might be primarily involved in the neuronal apoptosis and neurological deficits, and modulating the ER-mitochondrion crosstalk might be a novel therapeutic strategy for sTBI.
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Traumatismos Craneocerebrales , Estrés del Retículo Endoplásmico , Animales , Apoptosis , Retículo Endoplásmico/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Roedores , Proteínas de Transporte Vesicular/metabolismoRESUMEN
Neuroinflammation is an important mediator of secondary injury pathogenesis that exerts dual beneficial and detrimental effects on pathophysiology of the central nervous system (CNS) after traumatic brain injury (TBI). Fluvoxamine is a serotonin selective reuptake inhibitor (SSRI) and has been reported to have the anti-inflammatory properties. However, the mechanisms and therapeutic effects of fluvoxamine in neuroinflammation after TBI have not be defined. In this study, we showed that fluvoxamine inhibited peripheral immune cell infiltration and glia activation at 3 days in mice subjected to TBI. Fluvoxamine treatment promoted microglial/macrophage phenotypic transformation from pro-inflammatory M1-phenotype to anti-inflammatory M2-phenotype in in vivo and in vitro experiments. In addition, fluvoxamine treatment attenuated neuronal apoptosis, blood-brain barrier (BBB) disruption, cerebrovascular damage, and post-traumatic edema formation, thereby improving neurological function of mice subjected to TBI. These findings support the clinical evaluation of fluvoxamine as a neuroprotective therapy for TBI.
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Lesiones Traumáticas del Encéfalo , Microglía , Animales , Antiinflamatorios/farmacología , Lesiones Traumáticas del Encéfalo/complicaciones , Modelos Animales de Enfermedad , Fluvoxamina/farmacología , Fluvoxamina/uso terapéutico , Leucocitos/patología , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Microglía/patología , NeuroprotecciónRESUMEN
BACKGROUND: Endoplasmic reticulum (ER) stress and unfolded protein response (UPR) is associated with neuroinflammation and subsequent cell death following traumatic brain injury (TBI). The sigma-1 receptor (Sig-1R) acts as a dynamic pluripotent modulator of fundamental cellular processes at the mitochondria-associated membranes (MAMs). The activation of Sig-1R is neuroprotective in a variety of central nervous system diseases, but its impact on ER stress induced by traumatic brain injury is not known. This study investigated the role of Sig-1R in regulating the ER stress-mediated microglial activation and programmed cell death (apoptosis and pyroptosis) induced by TBI. METHODS: Ten human brain tissues were obtained from The Tianjin Medical University General Hospital. Four normal brain tissues were obtained from patients who underwent surgery for cerebral vascular malformation, through which peripheral brain tissues were isolated. Six severe TBI tissues were from patients with brain injury caused by accidents. None of the patients had any other known neurological disorders. Mice with Sig-1R deletion using CRISPR technology were subjected to controlled cortical impact-induced injury. In parallel, wild type C57BL/6J mice were analyzed for outcomes after they were exposed to TBI and received the Sig-1R agonist PRE-084 (10 mg/kg daily for three days) either alone or in combination with the Sig-1R antagonist BD-1047 (10 mg/kg). RESULTS: The expression of Sig-1R and the 78 kDa glucose-regulated protein, a known UPR marker, were significantly elevated in the injured cerebral tissues from TBI patients and mice subjected to TBI. PRE-084 improved neurological function, restored the cerebral cortical perfusion, and ameliorated and brain edema in C57BL/6J mice subjected to TBI by reducing endoplasmic reticulum stress-mediated apoptosis, pyroptosis, and microglia activation. The effect of PRE-084 was abolished in mice receiving Sig-1R antagonist BD-1047. CONCLUSIONS: ER stress and UPR were upregulated in TBI patients and mice subjected to TBI. Sig-1R activation by the exogenous activator PRE-084 attenuated microglial cells activation, reduced ER stress-associated programmed cell death, and restored cerebrovascular and neurological function in TBI mice.
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We propose to align distributional data from the perspective of Wasserstein means. We raise the problem of regularizing Wasserstein means and propose several terms tailored to tackle different problems. Our formulation is based on the variational transportation to distribute a sparse discrete measure into the target domain. The resulting sparse representation well captures the desired property of the domain while reducing the mapping cost. We demonstrate the scalability and robustness of our method with examples in domain adaptation, point set registration, and skeleton layout.
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Changes in cognitive performance due to neurodegenerative diseases such as Alzheimer's disease (AD) are closely correlated to the brain structure alteration. A univariate and personalized neurodegenerative biomarker with strong statistical power based on magnetic resonance imaging (MRI) will benefit clinical diagnosis and prognosis of neurodegenerative diseases. However, few biomarkers of this type have been developed, especially those that are robust to image noise and applicable to clinical analyses. In this paper, we introduce a variational framework to compute optimal transportation (OT) on brain structural MRI volumes and develop a univariate neuroimaging index based on OT to quantify neurodegenerative alterations. Specifically, we compute the OT from each image to a template and measure the Wasserstein distance between them. The obtained Wasserstein distance, Wasserstein Index (WI) for short to specify the distance to a template, is concise, informative and robust to random noise. Comparing to the popular linear programming-based OT computation method, our framework makes use of Newton's method, which makes it possible to compute WI in large-scale datasets. Experimental results, on 314 subjects (140 Aß + AD and 174 Aß- normal controls) from the Alzheimer's Disease Neuroimaging Initiative (ADNI) baseline dataset, provide preliminary evidence that the proposed WI is correlated with a clinical cognitive measure (the Mini-Mental State Examination (MMSE) score), and it is able to identify group difference and achieve a good classification accuracy, outperforming two other popular univariate indices including hippocampal volume and entorhinal cortex thickness. The current pilot work suggests the application of WI as a potential univariate neurodegenerative biomarker.
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Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Interpretación de Imagen Asistida por Computador/métodos , Neuroimagen/métodos , Anciano , Algoritmos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Proyectos PilotoRESUMEN
Fusing multimodal brain image features to empower statistical analysis has attracted considerable research interest. Generally, a feature mapping is learned in the fusion process so the cross-modality relationship in the multimodal data can be more effectively extracted in a common feature space. Most of the prior work achieve this goal by data-driven approaches without considering the geometry properties of the feature spaces where the data are embedded. It results in a huge sacrifice of untapped information. Here, we propose to fuse the multimodal brain images through a novel geometric approach. The key idea is to encode various brain image features with the local metric change on brain shapes, such that the feature mapping can be efficiently solved by some geometric mapping functions, i.e., quasiconformal and harmonic mappings. We approach our multimodal fusion framework (MFRM) in two steps: surface feature mapping and volumetric feature mapping. For each of them, we design an informative Riemannian metric based on distinct brain anatomical features and achieve image fusion via diffeomorphic maps. We evaluate our proposed method on two brain image cohorts. The experimental results reveal the effectiveness of our proposed framework which yields better statistical performances than state-of-the-art data-driven methods.
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We propose a new clustering method based on optimal transportation. We discuss the connection between optimal transportation and k-means clustering, solve optimal transportation with the variational principle, and investigate the use of power diagrams as transportation plans for aggregating arbitrary domains into a fixed number of clusters. We drive cluster centroids through the target domain while maintaining the minimum clustering energy by adjusting the power diagram. Thus, we simultaneously pursue clustering and the Wasserstein distance between the centroids and the target domain, resulting in a measure-preserving mapping. We demonstrate the use of our method in domain adaptation, remeshing, and learning representations on synthetic and real data.
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Fluorodeoxyglucose (FDG) positron emission tomography (PET) measures the decline in the regional cerebral metabolic rate for glucose, offering a reliable metabolic biomarker even on presymptomatic Alzheimer's disease (AD) patients. PET scans provide functional information that is unique and unavailable using other types of imaging. However, the computational efficacy of FDG-PET data alone, for the classification of various Alzheimers Diagnostic categories, has not been well studied. This motivates us to correctly discriminate various AD Diagnostic categories using FDG-PET data. Deep learning has improved state-of-the-art classification accuracies in the areas of speech, signal, image, video, text mining and recognition. We propose novel methods that involve probabilistic principal component analysis on max-pooled data and mean-pooled data for dimensionality reduction, and multilayer feed forward neural network which performs binary classification. Our experimental dataset consists of baseline data of subjects including 186 cognitively unimpaired (CU) subects, 336 mild cognitive impairment (MCI) subjects with 158 Late MCI and 178 Early MCI, and 146 AD patients from Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset. We measured F1-measure, precision, recall, negative and positive predictive values with a 10-fold cross validation scheme. Our results indicate that our designed classifiers achieve competitive results while max pooling achieves better classification performance compared to mean-pooled features. Our deep model based research may advance FDG-PET analysis by demonstrating their potential as an effective imaging biomarker of AD.
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AIM: To assess the feasibility and safety of a novel enteroscope, negative-pressure suction endoscope in examining the small intestine of a porcine model. METHODS: In vitro experiments in small intestinal loops from 20 pigs and in vivo experiments in 20 living pigs were conducted. RESULTS: In in vitro experiments, a negative pressure of > 0.06 MPa was necessary for optimal visualization of the intestine, and this pressure did not cause gross or histological damage to the mucosa. For satisfactory examination of the small intestine in vivo, higher negative pressure (> 1.00 MPa) was required. Despite this higher pressure, the small intestine did not show any gross or microscopic damage in the suctioned areas. The average time of examination in the living animals was 60 ± 7.67 min. The animals did not experience any apparent ill effects from the procedure. CONCLUSION: Small intestine endoscope was safely performed within a reasonable time period and enabled complete visualization of the intestine in most cases.
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Endoscopía Gastrointestinal/instrumentación , Endoscopía Gastrointestinal/métodos , Intestino Delgado/diagnóstico por imagen , Animales , Modelos Animales de Enfermedad , Estudios de Factibilidad , Técnicas In Vitro , Seguridad del Paciente , Presión , PorcinosRESUMEN
The alterations of brain structures and functions have been considered closely correlated to the change of cognitive performance due to neurodegenerative diseases such as Alzheimer's disease. In this paper, we introduce a variational framework to compute the optimal transformation (OT) in 3D space and propose a univariate neuroimaging index based on OT to measure such alterations. We compute the OT from each image to a template and measure the Wasserstein distance between them. By comparing the distances from all the images to the common template, we obtain a concise and informative index for each image. Our framework makes use of the Newton's method, which reduces the computational cost and enables itself to be applicable to large-scale datasets. The proposed work is a generic approach and thus may be applicable to various volumetric brain images, including structural magnetic resonance (sMR) and fluorodeoxyglucose positron emission tomography (FDG-PET) images. In the classification between Alzheimer's disease patients and healthy controls, our method achieves an accuracy of 82.30% on the Alzheimers Disease Neuroimaging Initiative (ADNI) baseline sMRI dataset and outperforms several other indices. On FDG-PET dataset, we boost the accuracy to 88.37% by leveraging pairwise Wasserstein distances. In a longitudinal study, we obtain a 5% significance with p-value = 1.13×105 in a t-test on FDG-PET. The results demonstrate a great potential of the proposed index for neuroimage analysis and the precision medicine research.