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1.
Proc Natl Acad Sci U S A ; 121(22): e2316117121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38776372

RESUMO

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.


Assuntos
Imageamento por Ressonância Magnética , Saimiri , Medula Espinal , Substância Branca , Animais , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia , Medula Espinal/fisiologia , Medula Espinal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Descanso/fisiologia , Oxigênio/sangue , Oxigênio/metabolismo , Masculino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/fisiologia , Feminino
2.
Artigo em Inglês | MEDLINE | ID: mdl-38783717

RESUMO

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.

3.
IEEE Trans Biomed Eng ; PP2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640051

RESUMO

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.

4.
Neuroimage ; 289: 120549, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382864

RESUMO

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.


Assuntos
Córtex Insular , Imageamento por Ressonância Magnética , Humanos , Ratos , Animais , Imageamento por Ressonância Magnética/métodos , Nociceptividade/fisiologia , Córtex Somatossensorial/diagnóstico por imagem , Córtex Somatossensorial/fisiologia , Mapeamento Encefálico , Dor
5.
Behav Brain Res ; 459: 114808, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38081518

RESUMO

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.


Assuntos
Imagem de Tensor de Difusão , Traumatismos da Medula Espinal , Animais , Humanos , Saimiri , Imagem de Tensor de Difusão/métodos , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Imagem de Difusão por Ressonância Magnética , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia
6.
Mol Imaging Biol ; 26(2): 240-252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38151582

RESUMO

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.


Assuntos
Contusões , Traumatismos da Medula Espinal , Ratos , Animais , Doenças Neuroinflamatórias , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia , Medula Espinal/patologia , Inflamação/metabolismo , Proteínas de Transporte/metabolismo
7.
J Control Release ; 363: 707-720, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37827222

RESUMO

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.


Assuntos
Barreira Hematoencefálica , Macaca , Animais , Barreira Hematoencefálica/patologia , Encéfalo/diagnóstico por imagem , Ultrassonografia , Sonicação/métodos , Imageamento por Ressonância Magnética , Microbolhas
8.
Brain Stimul ; 16(5): 1430-1444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37741439

RESUMO

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.


Assuntos
Nociceptividade , Núcleos Talâmicos , Núcleos Talâmicos/fisiologia , Tálamo , Encéfalo , Cognição
9.
J Med Imaging (Bellingham) ; 10(5): 055001, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37744953

RESUMO

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.

10.
Cereb Cortex Commun ; 4(3): tgad018, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37753115

RESUMO

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.

11.
Exp Mol Med ; 55(7): 1462-1478, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37394585

RESUMO

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.


Assuntos
RNA Longo não Codificante , Camundongos , Animais , RNA Longo não Codificante/metabolismo , Cirrose Hepática/metabolismo , Regulação da Expressão Gênica , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células Estreladas do Fígado/metabolismo
13.
Magn Reson Imaging ; 102: 184-200, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37343904

RESUMO

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.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Traumatismos da Medula Espinal , Animais , Humanos , Imagem de Tensor de Difusão/métodos , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia , Imageamento por Ressonância Magnética/métodos , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Modelos Animais
14.
Plant Dis ; 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37129350

RESUMO

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.

15.
Diagn Pathol ; 18(1): 33, 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36864456

RESUMO

BACKGROUND: Lung adenocarcinoma (LUAD) is a prevalent malignancy. SNHG15 has been demonstrated to be oncogenic in many kinds of cancers, however the mechanism of SNHG15 in LUAD cisplatin (DDP) resistance remains unclear. In this study, we demonstrated the effect of SNHG15 on DDP resistance in LUAD and its related mechanism. METHODS: Bioinformatics analysis was adopted to assess SNHG15 expression in LUAD tissues and predict the downstream genes of SNHG15. The binding relationship between SNHG15 and downstream regulatory genes was proved through RNA immunoprecipitation, chromatin immunoprecipitation and dual-luciferase reporter assays. Cell counting kit-8 assay was adopted to evaluate LUAD cell viability, and gene expression was determined by Western blot and quantitative real-time polymerase chain reaction. We then performed comet assay to assess DNA damage. Cell apoptosis was detected by Tunnel assay. Xenograft animal models were created to test the function of SNHG15 in vivo. RESULTS: SNHG15 was up-regulated in LUAD cells. Moreover, SNHG15 was also highly expressed in drug-resistant LUAD cells. Down-regulated SNHG15 strengthened the sensitivity of LUAD cells to DDP and induced DNA damage. SNHG15 could elevate ECE2 expression through binding with E2F1, and it could induce DDP resistance by modulating the E2F1/ECE2 axis. In vivo experiments verified that the SNHG15 could enhance DDP resistance in LUAD tissue. CONCLUSION: The results suggested that SNHG15 could up-regulate ECE2 expression by recruiting E2F1, thereby enhancing the DDP resistance of LUAD.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Animais , Humanos , Cisplatino/farmacologia , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Reparo do DNA/genética
16.
bioRxiv ; 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36909495

RESUMO

Focused ultrasound blood-brain barrier (BBB) opening is a promising tool for targeted delivery of therapeutic agents into the brain. The volume of opening determines the extent of therapeutic administration and sets a lower bound on the size of targets which can be selectively treated. We tested a custom 1 MHz array transducer optimized for cortical regions in the macaque brain with the goal of achieving small volume openings. We integrated this device into a magnetic resonance image guided focused ultrasound system and demonstrated twelve instances of small volume BBB opening with average opening volumes of 59 ± 37 mm 3 and 184 ± 2 mm 3 in cortical and subcortical targets, respectively. We developed real-time cavitation monitoring using a passive cavitation detector embedded in the array and characterized its performance on a bench-top flow phantom mimicking transcranial BBB opening procedures. We monitored cavitation during in-vivo procedures and compared cavitation metrics against opening volumes and safety outcomes measured with FLAIR and susceptibility weighted MR imaging. Our findings show small BBB opening at cortical targets in macaques and characterize the safe pressure range for 1 MHz BBB opening. Additionally, we used subject-specific simulations to investigate variance in measured opening volumes and found high correlation (R 2 = 0.8577) between simulation predictions and observed measurements. Simulations suggest the threshold for 1 MHz BBB opening was 0.53 MPa. This system enables BBB opening for drug delivery and gene therapy to be targeted to more specific brain regions.

17.
World J Gastroenterol ; 29(9): 1446-1459, 2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36998425

RESUMO

Liver fibrosis is a wound-healing response following chronic liver injury caused by hepatitis virus infection, obesity, or excessive alcohol. It is a dynamic and reversible process characterized by the activation of hepatic stellate cells and excess accumulation of extracellular matrix. Advanced fibrosis could lead to cirrhosis and even liver cancer, which has become a significant health burden worldwide. Many studies have revealed that noncoding RNAs (ncRNAs), including microRNAs, long noncoding RNAs and circular RNAs, are involved in the pathogenesis and development of liver fibrosis by regulating signaling pathways including transforming growth factor-ß pathway, phosphatidylinositol 3-kinase/protein kinase B pathway, and Wnt/ß-catenin pathway. NcRNAs in serum or exosomes have been reported to tentatively applied in the diagnosis and staging of liver fibrosis and combined with elastography to improve the accuracy of diagnosis. NcRNAs mimics, ncRNAs in mesenchymal stem cell-derived exosomes, and lipid nanoparticles-encapsulated ncRNAs have become promising therapeutic approaches for the treatment of liver fibrosis. In this review, we update the latest knowledge on ncRNAs in the pathogenesis and progression of liver fibrosis, and discuss the potentials and challenges to use these ncRNAs for diagnosis, staging and treatment of liver fibrosis. All these will help us to develop a comprehensive understanding of the role of ncRNAs in liver fibrosis.


Assuntos
MicroRNAs , RNA Longo não Codificante , Humanos , RNA não Traduzido/genética , Cirrose Hepática/diagnóstico , Cirrose Hepática/genética , Cirrose Hepática/terapia , Fibrose , RNA Longo não Codificante/genética , Via de Sinalização Wnt
18.
J Clin Med ; 12(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36836091

RESUMO

Abnormal blood pressure is common in critically ill stroke patients. However, the association between mean arterial pressure (MAP) and mortality of critically ill stroke patients remains unclear. We extracted eligible acute stroke patients from the MIMIC-III database. The patients were divided into three groups: a low MAP group (MAP ≤ 70 mmHg), a normal MAP group (70 mmHg < MAP ≤ 90 mmHg), and a high MAP group (MAP > 90 mmHg). The Cox proportional hazards model and restricted cubic splines were used to assess the association between MAP and mortality. Sensitivity analyses were conducted to investigate whether MAP had different effects on mortality in different subpopulations. A total of 2885 stroke patients were included in this study. The crude 7-day and 28-day mortality was significantly higher in the low MAP group than that in the normal MAP group. By contrast, patients in the high MAP group did not have higher crude 7-day and 28-day mortality than those in the normal MAP group. After multiple adjustments using the Cox regression model, patients with low MAP were consistently associated with higher 7-day and 28-day mortality than those with normal MAP in the following subgroups: age > 60 years, male, those with or without hypertension, those without diabetes, and those without CHD (p < 0.05), but patients with high MAP were not necessarily associated with higher 7-day and 28-day mortality after adjustments (most p > 0.05). Using the restricted cubic splines, an approximately L-shaped relationship was established between MAP and the 7-day and 28-day mortality in acute stroke patients. The findings were robust to multiple sensitivity analyses in stroke patients. In critically ill stroke patients, a low MAP significantly increased the 7-day and 28-day mortality, while a high MAP did not, suggesting that a low MAP is more harmful than a high MAP in critically ill stroke patients.

19.
ACS Appl Mater Interfaces ; 15(6): 7911-7918, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36719898

RESUMO

Achieving large-area organic photovoltaic (OPV) modules with reasonable cost and performance is an important step toward commercialization. In this work, solution-processed conventional and inverted OPV modules with an area of 216 cm2 were fabricated by the blade coating method. Film uniformity was controlled by adjusting the fabrication parameters of the blade coating procedure. The influence of the concentration of the solutions of the interfacial materials on OPV module performance was investigated. For OPV modules based on the PM6:Y6 photoactive layer, a certificated power conversion efficiency (PCE) of 9.10% was achieved for the conventional OPV modules based on the TASiW-12 interfacial layer while a certificated PCE of 11.27% was achieved for the inverted OPV modules based on the polyethylenimine (PEI) interfacial layer. As for OPV modules based on a commercially available photoactive layer, PV-X Plus, a PCE of 8.52% was achieved in the inverted OPV modules. A halogen-free solvent, o-xylene, was used as the solvent for PV-X Plus, which makes the industrial production much more environmentally friendly.

20.
Magn Reson Med ; 89(2): 729-737, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36161670

RESUMO

PURPOSE: To calculate temperatures from T2 *-weighted images collected during optogenetic fMRI based on proton resonance frequency (PRF) shift thermometry, to monitor confounding heating effects and determine appropriate light parameters for optogenetic stimulation. METHODS: fMRI is mainly based on long-TE gradient-recalled echo acquisitions that are also suitable for measuring small temperature changes via the PRF shift. A motion- and respiration-robust processing pipeline was developed to calculate temperature changes based on the PRF shift directly from the T2 *-weighted images collected for fMRI with a two-shot 2D gradient-recalled echo-EPI sequence at 9.4T. Optogenetic fMRI protocols which differed in stimulation durations (3, 6 and 9 s) within a total block duration of 30 s were applied in a squirrel monkey to validate the methods with blue and green light (20 Hz, 30 mW) delivery interleaved between periods. General linear modeling was performed on the resulting time series temperature maps to verify if light delivery with each protocol resulted in significant heating in the brain around the optical fiber. RESULTS: The temperature SD was 0.05°C with the proposed imaging protocol and processing. Statistical analysis showed that the optogenetic stimulation protocol with a 3 s stimulation duration did not result in significant temperature rises. Significant temperature rises up to 0.13°C (p < 0. 05) were observed with 6 and 9 s stimulation durations for blue and green light. CONCLUSION: The proposed processing pipeline can be useful for the design of optogenetic stimulation protocols and for monitoring confounding heating effects.


Assuntos
Imageamento por Ressonância Magnética , Optogenética , Imageamento por Ressonância Magnética/métodos , Calefação , Encéfalo/diagnóstico por imagem , Prótons , Lasers , Imagens de Fantasmas
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