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1.
Behav Brain Res ; 476: 115265, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307286

RESUMEN

We have previously demonstrated that machine learning-based video analysis, conducted via DeepLabCut, is more sensitive for detecting subtle deficits in hand grasping behavior than traditional end-point performance assessments. This superiority was observed in a nonhuman primate (NHP) model of cervical spinal cord injury, specifically a dorsal column lesion (DCL). The current study aims to further characterize the kinematic aspects of the deficits in hand reaching, grasping, and retrieving behavior from a 3D perspective following a DCL. Squirrel monkeys were trained to retrieve sugar pellets from eight wells, which were located either on a flat plate or a raised tube with varying well depths. This setup was designed to require coordinated finger movements during the task. Immediately after the DCL, the animals exhibited measurable behavioral deficits. These were characterized by significant increases in grasping speed squared and trial completion time, markedly widened movement trajectories of individual fingers, and abnormalities in inter-finger distance and orientation. Increased task difficulty was associated with more pronounced behavioral deficits. By three months post-DCL, video-based measurements indicated no significant recovery, even though global end-point performance had returned to baseline levels. Our findings demonstrate that deprivation of tactile information results in impaired dexterous hand behavior involving coordinated finger movements, and the impairment is sustained for 20 weeks. This spinal cord injury (SCI) model, along with DeepLapCut analysis, provides a valuable platform for separately evaluating sensory and motor functions and their contributions to dexterous hand behavior and may be used for evaluating therapeutic interventions using more sensitive behavioral outcome readouts.

2.
World J Gastroenterol ; 30(32): 3730-3738, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39221065

RESUMEN

This editorial discusses a recently published paper in the World Journal of Gastroenterology. Our research focuses on p53's regulatory mechanism for controlling ferroptosis, as well as the intricate connection between ferroptosis and liver diseases. Ferroptosis is a specific form of programmed cell death that is de-pendent on iron and displays unique features in terms of morphology, biology, and genetics, distinguishing it from other forms of cell death. Ferroptosis can affect the liver, which is a crucial organ responsible for iron storage and meta-bolism. Mounting evidence indicates a robust correlation between ferroptosis and the advancement of liver disorders. P53 has a dual effect on ferroptosis through various distinct signaling pathways. However, additional investigations are required to clarify the regulatory function of p53 metabolic targets in this complex association with ferroptosis. In the future, researchers should clarify the mechanisms by which ferroptosis and other forms of programmed cell death contribute to the progression of liver diseases. Identifying and controlling important regulatory factors associated with ferroptosis present a promising therapeutic strategy for liver disorders.


Asunto(s)
Ferroptosis , Hierro , Hepatopatías , Hígado , Transducción de Señal , Proteína p53 Supresora de Tumor , Ferroptosis/fisiología , Humanos , Hepatopatías/metabolismo , Hepatopatías/patología , Hierro/metabolismo , Hígado/metabolismo , Hígado/patología , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Animales , Progresión de la Enfermedad
3.
Mol Psychiatry ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215183

RESUMEN

Educational attainment (EA), socioeconomic status (SES) and cognition are phenotypically and genetically linked to health outcomes. However, the role of copy number variations (CNVs) in influencing EA/SES/cognition remains unclear. Using a large-scale (n = 305,401) genome-wide CNV-level association analysis, we discovered 33 CNV loci significantly associated with EA/SES/cognition, 20 of which were novel (deletions at 2p22.2, 2p16.2, 2p12, 3p25.3, 4p15.2, 5p15.33, 5q21.1, 8p21.3, 9p21.1, 11p14.3, 13q12.13, 17q21.31, and 20q13.33, as well as duplications at 3q12.2, 3q23, 7p22.3, 8p23.1, 8p23.2, 17q12 (105 kb), and 19q13.32). The genes identified in gene-level tests were enriched in biological pathways such as neurodegeneration, telomere maintenance and axon guidance. Phenome-wide association studies further identified novel associations of EA/SES/cognition-associated CNVs with mental and physical diseases, such as 6q27 duplication with upper respiratory disease and 17q12 (105 kb) duplication with mood disorders. Our findings provide a genome-wide CNV profile for EA/SES/cognition and bridge their connections to health. The expanded candidate CNVs database and the residing genes would be a valuable resource for future studies aimed at uncovering the biological mechanisms underlying cognitive function and related clinical phenotypes.

4.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(4): 1300-1304, 2024 Aug.
Artículo en Chino | MEDLINE | ID: mdl-39192435

RESUMEN

With the development of transfusion medicine, platelet pathogen contamination is of increasing concern to the industry. Currently, pathogen reduction technology (PRT) has been successfully applied to platelets and achieved good results. This paper provides an overview of the research progress of commercial platelet PRT, a comprehensive analysis of the current application status of platelet PRT, preclinical mechanism studies, clinical cohort studies and alternative or complementary strategies, and makes recommendations to provide a scientific basis for safeguarding blood safety in China and developing platelet PRT products applicable to our national conditions.


Asunto(s)
Plaquetas , Humanos , Plaquetas/microbiología , Seguridad de la Sangre , Transfusión de Plaquetas , China , Control de Calidad
5.
Artículo en Inglés | MEDLINE | ID: mdl-39024077

RESUMEN

Transcranial-focused ultrasound (tFUS) procedures such as neuromodulation and blood-brain barrier (BBB) opening require precise focus placement within the brain. MRI is currently the most reliable tool for focus localization but can be prohibitive for procedures requiring recurrent therapies. We designed, fabricated, and characterized a patient-specific, 3-D-printed, stereotactic frame for repeated tFUS therapy. The frame is compact, with minimal footprint, can be removed and re-secured between treatments while maintaining sub-mm accuracy, and will allow for precise and repeatable transcranial FUS treatment without the need for MR-guidance following the initial calibration scan. Focus localization and repeatability were assessed via MR-thermometry and MR-acoustic radiation force imaging (ARFI) on an ex vivo skull phantom and in vivo nonhuman primates (NHPs), respectively. Focal localization, registration, steering, and re-steering were accomplished during the initial MRI calibration scan session. Keeping steering coordinates fixed in subsequent therapy and imaging sessions, we found good agreement between steered foci and the intended target, with target registration error (TRE) of 1.2 ± 0.3 ( n = 4 , ex vivo) and 1.0 ± 0.5 ( n = 3 , in vivo) mm. Focus position (steered and non-steered) was consistent, with sub-mm variation in each dimension between studies. Our 3-D-printed, patient-specific stereotactic frame can reliably position and orient the ultrasound transducer for repeated targeting of brain regions using a single MR-based calibration. The compact frame allows for high-precision tFUS to be carried out outside the magnet and could help reduce the cost of tFUS treatments where repeated application of an ultrasound focus is required with high precision.


Asunto(s)
Diseño de Equipo , Fantasmas de Imagen , Animales , Humanos , Terapia por Ultrasonido/métodos , Terapia por Ultrasonido/instrumentación , Imagen por Resonancia Magnética/métodos , Técnicas Estereotáxicas/instrumentación , Impresión Tridimensional , Encéfalo/diagnóstico por imagen , Macaca mulatta
6.
Theranostics ; 14(9): 3548-3564, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948068

RESUMEN

Over the past two decades, metronomic chemotherapy has gained considerable attention and has demonstrated remarkable success in the treatment of cancer. Through chronic administration and low-dose regimens, metronomic chemotherapy is associated with fewer adverse events but still effectively induces disease control. The identification of its antiangiogenic properties, direct impact on cancer cells, immunomodulatory effects on the tumour microenvironment, and metabolic reprogramming ability has established the intrinsic multitargeted nature of this therapeutic approach. Recently, the utilization of metronomic chemotherapy has evolved from salvage treatment for metastatic disease to adjuvant maintenance therapy for high-risk cancer patients, which has been prompted by the success of several substantial phase III trials. In this review, we delve into the mechanisms underlying the antitumour effects of metronomic chemotherapy and provide insights into potential combinations with other therapies for the treatment of various malignancies. Additionally, we discuss health-economic advantages and candidates for the utilization of this treatment option.


Asunto(s)
Administración Metronómica , Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/tratamiento farmacológico , Microambiente Tumoral/efectos de los fármacos , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación
7.
Proc Natl Acad Sci U S A ; 121(22): e2316117121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38776372

RESUMEN

We report the reliable detection of reproducible patterns of blood-oxygenation-level-dependent (BOLD) MRI signals within the white matter (WM) of the spinal cord during a task and in a resting state. Previous functional MRI studies have shown that BOLD signals are robustly detectable not only in gray matter (GM) in the brain but also in cerebral WM as well as the GM within the spinal cord, but similar signals in WM of the spinal cord have been overlooked. In this study, we detected BOLD signals in the WM of the spinal cord in squirrel monkeys and studied their relationships with the locations and functions of ascending and descending WM tracts. Tactile sensory stimulus -evoked BOLD signal changes were detected in the ascending tracts of the spinal cord using a general-linear model. Power spectral analysis confirmed that the amplitude at the fundamental frequency of the response to a periodic stimulus was significantly higher in the ascending tracts than the descending ones. Independent component analysis of resting-state signals identified coherent fluctuations from eight WM hubs which correspond closely to the known anatomical locations of the major WM tracts. Resting-state analyses showed that the WM hubs exhibited correlated signal fluctuations across spinal cord segments in reproducible patterns that correspond well with the known neurobiological functions of WM tracts in the spinal cord. Overall, these findings provide evidence of a functional organization of intraspinal WM tracts and confirm that they produce hemodynamic responses similar to GM both at baseline and under stimulus conditions.


Asunto(s)
Imagen por Resonancia Magnética , Saimiri , Médula Espinal , Sustancia Blanca , Animales , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/fisiología , Médula Espinal/fisiología , Médula Espinal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Descanso/fisiología , Oxígeno/sangre , Oxígeno/metabolismo , Masculino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/fisiología , Femenino
8.
Artículo en Inglés | MEDLINE | ID: mdl-38783717

RESUMEN

CONTEXT: Small cohorts of youth with congenital adrenal hyperplasia (CAH) demonstrate increased risk of obesity and poor cardiometabolic health. OBJECTIVE: To determine the odds of cardiometabolic-related diagnoses in youth with CAH compared to matched controls in a cross-sectional analysis in a large, multisite database (PEDSnet). DESIGN: Electronic health record data (2009-2019) were used to determine odds of cardiometabolic-related outcomes based on diagnosis, anthropometric and laboratory data using logistic regression among youth with CAH vs. controls. SETTING: Six PEDSnet sites. PATIENTS OR OTHER PARTICIPANTS: Youth with CAH and >1 outpatient visit in PEDSnet (n=1,647) were propensity-score matched on 8 variables to controls (n=6,588). A subset of youth with classic CAH (n=547, with glucocorticoid and mineralocorticoid prescriptions) were matched to controls (n=2,188). INTERVENTION(S): N/A. MAIN OUTCOME MEASURE(S): Odds of having cardiometabolic-related diagnoses among youth over 2 years with CAH compared to matched controls. RESULTS: Outcomes were calculated for all individuals with CAH (median age at last visit 12.9 years [7.3, 17.6]) and a subset with classic CAH (median age at last visit 11.6 years [4.7, 17.5]) compared to their matched controls. All patients with CAH had higher odds of overweight/obesity (odds ratio [95% confidence interval] 3.63 [3.24,4.07]), hypertension (3.07 [2.60,3.64]), dysglycemia (1.95 [1.35,2.82], dyslipidemia (2.28 [1.79,2.91]) and liver dysfunction (2.30 [1.91,2.76]) compared to matched controls. Patients with classic CAH had higher odds of overweight/obesity (3.21 [2.61,3.93]), hypertension (8.22 [6.71,10.08]), and liver dysfunction (2.11 [1.55,2.89]) compared to matched controls. CONCLUSIONS: Overall, youth with CAH are at increased risk of diagnoses related to worse cardiometabolic health.

9.
IEEE Trans Biomed Eng ; 71(9): 2740-2748, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38640051

RESUMEN

OBJECTIVE: Transcranial focused ultrasound (tFUS) is being explored for neuroscience research and clinical applications due to its ability to affect precise brain regions noninvasively. The ability to target specific brain regions and localize the beam during these procedures is important for these applications to avoid damage and minimize off-target effects. Here, we present a method to combine optical tracking with magnetic resonance (MR) acoustic radiation force imaging to achieve targeting and localizing of the tFUS beam. This combined method provides steering coordinates to target brain regions within a clinically practical time frame. METHODS: Using an optically tracked hydrophone and bias correction with MR imaging we transformed the FUS focus coordinates into the MR space for targeting and error correction. We validated this method in vivo in 18 macaque FUS studies. RESULTS: Across these in vivo studies a single localization scan allowed for the average targeting error to be reduced from 4.8 mm to 1.4 mm and for multiple brain regions to be targeted with one transducer position. CONCLUSIONS: By reducing targeting error and providing the means to target multiple brain regions within a single session with high accuracy this method will allow further study of the effects of tFUS neuromodulation with more advanced approaches such as simultaneous dual or multi-site brain stimulation.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Animales , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Macaca mulatta , Reproducibilidad de los Resultados
10.
Neuroimage ; 289: 120549, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38382864

RESUMEN

The directional organization of multiple nociceptive regions, particularly within obscure operculoinsular areas, underlying multidimensional pain processing remains elusive. This study aims to establish the fundamental organization between somatosensory and insular cortices in routing nociceptive information. By employing an integrated multimodal approach of high-field fMRI, intracranial electrophysiology, and transsynaptic viral tracing in rats, we observed a hierarchically organized connection of S1/S2 → posterior insula → anterior insula in routing nociceptive information. The directional nociceptive pathway determined by early fMRI responses was consistent with that examined by early evoked LFP, intrinsic effective connectivity, and anatomical projection, suggesting fMRI could provide a valuable facility to discern directional neural circuits in animals and humans non-invasively. Moreover, our knowledge of the nociceptive hierarchical organization of somatosensory and insular cortices and the interface role of the posterior insula may have implications for the development of targeted pain therapies.


Asunto(s)
Corteza Insular , Imagen por Resonancia Magnética , Humanos , Ratas , Animales , Imagen por Resonancia Magnética/métodos , Nocicepción/fisiología , Corteza Somatosensorial/diagnóstico por imagen , Corteza Somatosensorial/fisiología , Mapeo Encefálico , Dolor
11.
Behav Brain Res ; 459: 114808, 2024 02 29.
Artículo en Inglés | MEDLINE | ID: mdl-38081518

RESUMEN

A mathematical model-based parcellation of magnetic resonance diffusion tensor images (DTI) has been developed to quantify progressive changes in three types of tissues - grey (GM), white matter (WM), and damaged spinal cord tissue, along with behavioral assessments over a 6 month period following targeted spinal cord injuries (SCI) in monkeys. Sigmoid Gompertz function based fittings of DTI metrics provide early indicators that correlate with, and predict, recovery of hand grasping behavior. Our three tissue pool model provided unbiased, data-driven segmentation of spinal cord images and identified DTI metrics that can serve as reliable biomarkers of severity of spinal cord injuries and predictors of behavioral outcomes.


Asunto(s)
Imagen de Difusión Tensora , Traumatismos de la Médula Espinal , Animales , Humanos , Saimiri , Imagen de Difusión Tensora/métodos , Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Imagen de Difusión por Resonancia Magnética , Traumatismos de la Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/patología
12.
Mol Imaging Biol ; 26(2): 240-252, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38151582

RESUMEN

PURPOSE: The degree and dynamic progression of neuroinflammation after traumatic spinal cord injuries (SCI) are crucial determinants of the severity of injury and potential for recovery. We used Positron Emission Tomography (PET) to monitor neuroinflammation longitudinally, correlating it with Chemical Exchange Saturation Transfer (CEST) Magnetic Resonance Imaging (MRI) and behavior in contusion-injured rats. These studies help validate CEST metrics and confirm how imaging may be used to evaluate the efficacy of therapies and understand their mechanisms of action. PROCEDURES: 12 SCI and 4 sham surgery rats were subjected to CEST MRI and PET-Translocator Protein (TSPO) scans for 8 weeks following injury. Z-spectra from the SCI were analyzed using a 5-Lorentzian pool model for fitting. Weekly motor and somatosensory behavior were correlated with imaging metrics, which were validated through post-mortem histological and immuo-staining using ionized calcium-binding adaptor protein-1 (iba-1, microglia) and glial fibrillary acidic protein (GFAP, astrocytes). RESULTS: PET-TSPO showed widespread inflammation and post-mortem histology confirmed the presence of activated microglia. Changes in CEST and nuclear Overhauser Effect (NOE) peaks at 3.5 ppm and -1.6 ppm respectively were largest within the first week after injury and more pronounced in rostral versus caudal segments. These temporal indices of neuroinflammation corresponded to the recovery of locomotor behaviors and somatic sensation in rats with moderate contusion injury. The results confirm that CEST MRI metrics are sensitive indices of states of neuroinflammation within injured spinal cords. CONCLUSIONS: The detection of dynamic spatiotemporal features of neuroinflammation progression underscores the importance of considering their timings and locations for neuroprotective and anti-inflammatory therapies. The availability of noninvasive MRI indices of neuroinflammation may facilitate clinical trials aimed at treatments that promote recovery after SCI.


Asunto(s)
Contusiones , Traumatismos de la Médula Espinal , Ratas , Animales , Enfermedades Neuroinflamatorias , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/patología , Médula Espinal/patología , Inflamación/metabolismo , Proteínas Portadoras/metabolismo
13.
J Control Release ; 363: 707-720, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37827222

RESUMEN

The use of focused ultrasound to open the blood-brain barrier (BBB) has the potential to deliver drugs to specific regions of the brain. The size of the BBB opening and ability to localize the opening determines the spatial extent and is a limiting factor in many applications of BBB opening where targeting a small brain region is desired. Here we evaluate the performance of a system designed for small opening volumes and highlight the unique challenges associated with pushing the spatial precision of this technique. To achieve small volume openings in cortical regions of the macaque brain, we tested a custom 1 MHz array transducer integrated into a magnetic resonance image-guided focused ultrasound system. Using real-time cavitation monitoring, we demonstrated twelve instances of single sonication, small volume BBB opening with average volumes of 59 ± 37 mm3 and 184 ± 2 mm3 in cortical and subcortical targets, respectively. We found high correlation between subject-specific acoustic simulations and observed openings when incorporating grey matter segmentation (R2 = 0.8577), and the threshold for BBB opening based on simulations was 0.53 MPa. Analysis of MRI-based safety assessment and cavitation signals indicate a safe pressure range for 1 MHz BBB opening and suggest that our system can be used to deliver drugs and gene therapy to small brain regions.


Asunto(s)
Barrera Hematoencefálica , Macaca , Animales , Barrera Hematoencefálica/patología , Encéfalo/diagnóstico por imagen , Ultrasonografía , Sonicación/métodos , Imagen por Resonancia Magnética , Microburbujas
14.
Brain Stimul ; 16(5): 1430-1444, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37741439

RESUMEN

BACKGROUND: MRI-guided transcranial focused ultrasound (MRgFUS) as a next-generation neuromodulation tool can precisely target and stimulate deep brain regions with high spatial selectivity. Combined with MR-ARFI (acoustic radiation force imaging) and using fMRI BOLD signal as functional readouts, our previous studies have shown that low-intensity FUS can excite or suppress neural activity in the somatosensory cortex. OBJECTIVE: To investigate whether low-intensity FUS can suppress nociceptive heat stimulation-induced responses in thalamic nuclei during hand stimulation, and to determine how this suppression influences the information processing flow within nociception networks. FINDINGS: BOLD fMRI activations evoked by 47.5 °C heat stimulation of hand were detected in 24 cortical regions, which belong to sensory, affective, and cognitive nociceptive networks. Concurrent delivery of low-intensity FUS pulses (650 kHz, 550 kPa) to the predefined heat nociceptive stimulus-responsive thalamic centromedial_parafascicular (CM_para), mediodorsal (MD), ventral_lateral (VL_ and ventral_lateral_posteroventral (VLpv) nuclei suppressed their heat responses. Off-target cortical areas exhibited reduced, enhanced, or no significant fMRI signal changes, depending on the specific areas. Differentiable thalamocortical information flow during the processing of nociceptive heat input was observed, as indicated by the time to reach 10% or 30% of the heat-evoked BOLD signal peak. Suppression of thalamic heat responses significantly altered nociceptive processing flow and direction between the thalamus and cortical areas. Modulation of contralateral versus ipsilateral areas by unilateral thalamic activity differed. Signals detected in high-order cortical areas, such as dorsal frontal (DFC) and ventrolateral prefrontal (vlPFC) cortices, exhibited faster response latencies than sensory areas. CONCLUSIONS: The concurrent delivery of FUS suppressed nociceptive heat response in thalamic nuclei and disrupted the nociceptive network. This study offers new insights into the causal functional connections within the thalamocortical networks and demonstrates the modulatory effects of low-intensity FUS on nociceptive information processing.


Asunto(s)
Nocicepción , Núcleos Talámicos , Núcleos Talámicos/fisiología , Tálamo , Encéfalo , Cognición
15.
Cereb Cortex Commun ; 4(3): tgad018, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37753115

RESUMEN

Resting-state fMRI based on analyzing BOLD signals is widely used to derive functional networks in the brain and how they alter during disease or injury conditions. Resting-state networks can also be used to study brain functional connectomes across species, which provides insights into brain evolution. The squirrel monkey (SM) is a non-human primate (NHP) that is widely used as a preclinical model for experimental manipulations to understand the organization and functioning of the brain. We derived resting-state networks from the whole brain of anesthetized SMs using Independent Component Analysis of BOLD acquisitions. We detected 15 anatomically constrained resting-state networks localized in the cortical and subcortical regions as well as in the white-matter. Networks encompassing visual, somatosensory, executive control, sensorimotor, salience and default mode regions, and subcortical networks including the Hippocampus-Amygdala, thalamus, basal-ganglia and brainstem region correspond well with previously detected networks in humans and NHPs. The connectivity pattern between the networks also agrees well with previously reported seed-based resting-state connectivity of SM brain. This study demonstrates that SMs share remarkable homologous network organization with humans and other NHPs, thereby providing strong support for their suitability as a translational animal model for research and additional insight into brain evolution across species.

16.
J Med Imaging (Bellingham) ; 10(5): 055001, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37744953

RESUMEN

Purpose: Transcranial focused ultrasound (tFUS) is a therapeutic ultrasound method that focuses sound through the skull to a small region noninvasively and often under magnetic resonance imaging (MRI) guidance. CT imaging is used to estimate the acoustic properties that vary between individual skulls to enable effective focusing during tFUS procedures, exposing patients to potentially harmful radiation. A method to estimate acoustic parameters in the skull without the need for CT is desirable. Approach: We synthesized CT images from routinely acquired T1-weighted MRI using a 3D patch-based conditional generative adversarial network and evaluated the performance of synthesized CT (sCT) images for treatment planning with tFUS. We compared the performance of sCT with real CT (rCT) images for tFUS planning using Kranion and simulations using the acoustic toolbox, k-Wave. Simulations were performed for 3 tFUS scenarios: (1) no aberration correction, (2) correction with phases calculated from Kranion, and (3) phase shifts calculated from time reversal. Results: From Kranion, the skull density ratio, skull thickness, and number of active elements between rCT and sCT had Pearson's correlation coefficients of 0.94, 0.92, and 0.98, respectively. Among 20 targets, differences in simulated peak pressure between rCT and sCT were largest without phase correction (12.4%±8.1%) and smallest with Kranion phases (7.3%±6.0%). The distance between peak focal locations between rCT and sCT was <1.3 mm for all simulation cases. Conclusions: Real and synthetically generated skulls had comparable image similarity, skull measurements, and acoustic simulation metrics. Our work demonstrated similar results for 10 testing cases comparing MR-sCTs and rCTs for tFUS planning. Source code and a docker image with the trained model are available at https://github.com/han-liu/SynCT_TcMRgFUS.

18.
Exp Mol Med ; 55(7): 1462-1478, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37394585

RESUMEN

The role of Gli-similar 2 (Glis2) in hepatic fibrosis (HF) is controversial. In this study, we focused on the functional and molecular mechanisms involved in the Glis2-mediated activation of hepatic stellate cells (HSCs)-a milestone event leading to HF. The expression levels of Glis2 mRNA and protein were significantly decreased in the liver tissues of patients with severe HF and in mouse fibrotic liver tissues as well as HSCs activated by TGFß1. Functional studies indicated that upregulated Glis2 significantly inhibited HSC activation and alleviated BDL-induced HF in mice. Downregulation of Glis2 was found to correlate significantly with DNA methylation of the Glis2 promoter mediated by methyltransferase 1 (DNMT1), which restricted the binding of hepatic nuclear factor 1-α (HNF1-α), a liver-specific transcription factor, to Glis2 promoters. In addition, the enrichment of DNMT1 in the Glis2 promoter region was mediated by metastasis-associated lung adenocarcinoma transcriptor-1 (MALAT1) lncRNA, leading to transcriptional silencing of Glis2 and activation of HSCs. In conclusion, our findings reveal that the upregulation of Glis2 can maintain the resting state of HSCs. The decreased expression of Glis2 under pathological conditions may lead to the occurrence and development of HF with the expression silencing of DNA methylation mediated by MALAT1 and DNMT1.


Asunto(s)
ARN Largo no Codificante , Ratones , Animales , ARN Largo no Codificante/metabolismo , Cirrosis Hepática/metabolismo , Regulación de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Células Estrelladas Hepáticas/metabolismo
19.
Magn Reson Imaging ; 102: 184-200, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37343904

RESUMEN

Multi-parametric MRI (mpMRI) technology enables non-invasive and quantitative assessments of the structural, molecular, and functional characteristics of various neurological diseases. Despite the recognized importance of studying spinal cord pathology, mpMRI applications in spinal cord research have been somewhat limited, partly due to technical challenges associated with spine imaging. However, advances in imaging techniques and improved image quality now allow longitudinal investigations of a comprehensive range of spinal cord pathological features by exploiting different endogenous MRI contrasts. This review summarizes the use of mpMRI techniques including blood oxygenation level-dependent (BOLD) functional MRI (fMRI), diffusion tensor imaging (DTI), quantitative magnetization transfer (qMT), and chemical exchange saturation transfer (CEST) MRI in monitoring different aspects of spinal cord pathology. These aspects include cyst formation and axonal disruption, demyelination and remyelination, changes in the excitability of spinal grey matter and the integrity of intrinsic functional circuits, and non-specific molecular changes associated with secondary injury and neuroinflammation. These approaches are illustrated with reference to a nonhuman primate (NHP) model of traumatic cervical spinal cord injuries (SCI). We highlight the benefits of using NHP SCI models to guide future studies of human spinal cord pathology, and demonstrate how mpMRI can capture distinctive features of spinal cord pathology that were previously inaccessible. Furthermore, the development of mechanism-based MRI biomarkers from mpMRI studies can provide clinically useful imaging indices for understanding the mechanisms by which injured spinal cords progress and repair. These biomarkers can assist in the diagnosis, prognosis, and evaluation of therapies for SCI patients, potentially leading to improved outcomes.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Traumatismos de la Médula Espinal , Animales , Humanos , Imagen de Difusión Tensora/métodos , Traumatismos de la Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/patología , Imagen por Resonancia Magnética/métodos , Médula Espinal/diagnóstico por imagen , Médula Espinal/patología , Modelos Animales
20.
Plant Dis ; 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129350

RESUMEN

Zizania latifolia is perennial plant, belonging to the rice tribe (Oryzeae) of the grass family Poaceae (Xu et al. 2020), which is also called jiaobai in China and commonly consumed as a vegetable crop. In 2022, a sheath rot occurred on Z. latifolia plants in Lishui, the Zhejiang Province of China. Symptoms occurred on the leaf sheath and initially showed as water-soaked chlorotic spots, later enlarging to irregular, elliptic, and elongated dark brown necrotic lesions. Later, lesions fused and extended to most of the leaf sheath leading to wilting. Almost 60% of the surveyed Z. latifolia plants in 100 hectare were affected. Diseased samples were collected for pathogen isolation. Symptomatic tissues were taken from the edge of lesions, sterilized for 10 s in 70% ethanol, then 2 min in 1% NaClO, washed three times with sterile distilled water, and placed on potato dextrose agar (PDA) at 26 °C in the dark. Fungal colonies displaying similar morphology were picked and purified by single spore isolation. In total, 8 isolates were obtained from 8 plant samples. When cultured on PDA, fungal colonies were white, gradually turning pale yellow with time. Macroconidia only were produced on Carnation leaf agar (CLA) and were hyaline, slender, falcate with single foot cells, 3 to 5 septate, and measured 29 to 50 µm × 3.75 to 5.0 µm. Chlamydospores were globose to subglobose and measured 6.8 to 16.5 µm. These morphological features were consistent with the description of Fusarium asiaticum (Leslie and Summerell 2006). For molecular identification, the partial translation elongation factor 1 alpha (TEF1-α) gene and RNA polymerase II second largest subunit (RPB2) gene of three representative isolates were amplified and sequenced (O'Donnell et al. 1998). These sequences were identical to each other, and one representative, Z-3-1, was deposited in GenBank (Accession No. OQ129437 and OQ858619, respectively). Analysis of the TEF1-α and RPB2 sequences of Z-3-1 showed that they were 99.85% (688/689) and 100% (945/945) identical to F. asiaticum strain Daya350-3 (KT380124) and MRC 1976 (MH582121), respectively, in NCBI, and had 99.38% and 100% identity to F. asiaticum strain CBS 110257 (AF212451 and JX171573) in Fusarium-ID. A combined phylogenetic tree based on the TEF1-α and RPB2 sequences showed that Z-3-1 was clustered with F. asiaticum using the neighbor-joining algorithm. Pathogenicity testing was conducted by inoculating potted Z. latifolia plants with a 1×105 conidial suspension of isolate Z-3-1, which was prepared by culturing the fungal strain in PDB at 26°C for 4 days in a shaker incubator. Conidial suspensions (1 mL) were dropped onto sheaths of potted Z. latifolia plants with sterile water serving as controls. All inoculated plants were covered with plastic bags and maintained in a humid growth chamber at 26°C with a photoperiod of 16 h. The inoculation experiment was repeated twice with 5 replicates per test. Four days later, the sheaths of potted inoculated plants displayed symptoms similar to those observed in the field. No symptoms were observed on control plants. Fusarium asiaticum was re-isolated specifically from the symptomatic inoculated Z. latifolia plants and confirmed by morphological and molecular methods, thus fulfilling Koch's postulates. Fusarium asiaticum has been reported to be a pathogen of other plants in China, such as Ligusticum (Zhu et al. 2022) and Setaria italica (Kong et al. 2022). To our knowledge, this is the first report of F. asiaticum causing sheath rot of Z. latifolia in China. The identification of the pathogen is the first step in developing appropriate field management strategies for this new disease.

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