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1.
Osteology (Basel) ; 4(2): 98-110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39474235

RESUMO

Evaluation of 3D bone morphology of the glenohumeral joint is necessary for pre-surgical planning. Zero echo time (ZTE) magnetic resonance imaging (MRI) provides excellent bone contrast and can potentially be used in place of computed tomography. Segmentation of shoulder anatomy, particularly humeral head and acetabulum, is needed for detailed assessment of each anatomy and for pre-surgical preparation. In this study we compared performance of two popular deep learning models based on Google's DeepLab and U-Net to perform automated segmentation on ZTE MRI of human shoulders. Axial ZTE images of normal shoulders (n=31) acquired at 3-Tesla were annotated for training with a DeepLab and 2D U-Net, and the trained model was validated with testing data (n=13). While both models showed visually satisfactory results for segmenting the humeral bone, U-Net slightly over-estimated while DeepLab under-estimated the segmented area compared to the ground truth. Testing accuracy quantified by Dice score was significantly higher (p<0.05) for U-Net (88%) than DeepLab (81%) for the humeral segmentation. We have also implemented the U-Net model onto an MRI console for a push-button DL segmentation processing. Although this is an early work with limitations, our approach has the potential to improve shoulder MR evaluation hindered by manual post-processing and may provide clinical benefit for quickly visualizing bones of the glenohumeral joint.

2.
J Imaging ; 10(9)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39330443

RESUMO

Non-contrast magnetic resonance angiography (NC-MRA), including fresh blood imaging (FBI), is a suitable choice for evaluating patients with peripheral artery disease (PAD). We evaluated standard FBI (sFBI) and centric ky-kz FBI (cFBI) acquisitions, using 1D and 2D parallel imaging factors (PIFs) to assess the trade-off between scan time and image quality due to blurring. The bilateral legs of four volunteers (mean age 33 years, two females) were imaged in the coronal plane using a body array coil with a posterior spine coil. Two types of sFBI and cFBI sequences with 1D PIF factor 5 in the phase encode (PE) direction (in-plane) and 2D PIF 3 (PE) × 2 (slice encode (SE)) (in-plane, through-slice) were studied. Image quality was evaluated by a radiologist, the vessel's signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured, and major vessel width was measured on the coronal maximum intensity projection (MIP) and 80-degree MIP. Results showed significant time reductions from 184 to 206 s on average when using sFBI down to 98 to 162 s when using cFBI (p = 0.003). Similar SNRs (averaging 200 to 370 across all sequences and PIF) and CNRs (averaging 190 to 360) for all techniques (p > 0.08) were found. There was no significant difference in the image quality (averaging 4.0 to 4.5; p > 0.2) or vessel width (averaging 4.1 to 4.9 mm; p > 0.1) on coronal MIP due to sequence or PIF. However, vessel width measured using 80-degree MIP demonstrated a significantly wider vessel in cFBI (5.6 to 6.8 mm) compared to sFBI (4.5 to 4.7 mm) (p = 0.022), and in 1D (4.7 to 6.8 mm) compared to 2D (4.5 to 5.6 mm) (p < 0.05) PIF. This demonstrated a trade-off in T2 blurring between 1D and 2D PIF: 1D using a PIF of 5 shortened the acquisition window, resulting in sharper arterial blood vessels in coronal images but significant blur in the 80-degree MIP. Two-dimensional PIF for cFBI provided a good balance between shorter scan time (relative to sFBI) and good sharpness in both in- and through-plane, while no benefit of 2D PIF was seen for sFBI. In conclusion, this study demonstrated the usefulness of FBI-based techniques for peripheral artery imaging and underscored the need to strike a balance between scan time and image quality in different planes through the use of 2D parallel imaging.

3.
Magn Reson Med Sci ; 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39231732

RESUMO

PURPOSE: Fresh blood imaging (FBI) utilizes physiological blood signal differences between diastole and systole, causing a long acquisition time. The purpose of this study is to develop a fast FBI technique using a centric ky - kz k-space trajectory (cFBI) and an exponential refocusing flip angle (eFA) scheme with fast longitudinal restoration. METHODS: This study was performed on 8 healthy subjects and 2 patients (peripheral artery disease and vascular disease) with informed consent, using a clinical 3-Tesla MRI scanner. A numeric simulation using extended phase graph (EPG) and phantom studies of eFA were carried out to investigate the restoration of longitudinal signal by lowering refocusing flip angles in later echoes. cFBI was then acquired on healthy subjects at the popliteal artery station to assess the effect of varying high/low flip ratios on the longitudinal restoration effects. In addition, trigger-delays of cFBI were optimized owing to the long acquisition window in zigzag centric ky - kz k-space trajectory. After optimizations, cFBI images were compared against standard FBI (sFBI) images in terms of scan time, motion artifacts, Nyquist N/2 artifacts, blurring, and overall image quality. We also performed two-way repeated measures analysis of variance. RESULTS: cFBI with eFA achieved nearly a 50% scan time reduction compared to sFBI. The high/low flip angle of 180/2 degrees with lower refocusing pulses shows fast longitudinal restoration with the highest blood signals, yet also more sensitive to the background signals. Overall, 180/30 degrees images show reasonable blood signal recovery while minimizing the background signal artifacts. After the trigger delay optimization, maximum intensity projection image of cFBI after systole-diastole subtraction demonstrates less motion and N/2 artifacts than that of sFBI. CONCLUSION: Together with eFA for fast longitudinal signal restoration, the proposed cFBI technique achieved a 2-fold reduction in scan time and improved image quality without major artifacts.

4.
Sensors (Basel) ; 24(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39275753

RESUMO

INTRODUCTION: The disco-vertebral junction (DVJ) of the lumbar spine contains thin structures with short T2 values, including the cartilaginous endplate (CEP) sandwiched between the bony vertebral endplate (VEP) and the nucleus pulposus (NP). We previously demonstrated that ultrashort-echo-time (UTE) MRI, compared to conventional MRI, is able to depict the tissues at the DVJ with improved contrast. In this study, we sought to further optimize UTE MRI by characterizing the contrast-to-noise ratio (CNR) of these tissues when either single echo or echo subtraction images are used and with varying echo times (TEs). METHODS: In four cadaveric lumbar spines, we acquired 3D Cones (a UTE sequence) images at varying TEs from 0.032 ms to 16 ms. Additionally, spin echo T1- and T2-weighted images were acquired. The CNRs of CEP-NP and CEP-VEP were measured in all source images and 3D Cones echo subtraction images. RESULTS: In the spin echo images, it was challenging to distinguish the CEP from the VEP, as both had low signal intensity. However, the 3D Cones source images at the shortest TE of 0.032 ms provided an excellent contrast between the CEP and the VEP. As the TE increased, the contrast decreased in the source images. In contrast, the 3D Cones echo subtraction images showed increasing CNR values as the second TE increased, reaching statistical significance when the second TE was above 10 ms (p < 0.05). CONCLUSIONS: Our study highlights the feasibility of incorporating UTE MRI for the evaluation of the DVJ and its advantages over conventional spin echo sequences for improving the contrast between the CEP and adjacent tissues. Additionally, modulation of the contrast for the target tissues can be achieved using either source images or subtraction images, as well as by varying the echo times.


Assuntos
Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Vértebras Lombares/diagnóstico por imagem , Disco Intervertebral/diagnóstico por imagem , Razão Sinal-Ruído , Imageamento Tridimensional/métodos , Núcleo Pulposo/diagnóstico por imagem
5.
J Clin Med ; 13(16)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39200736

RESUMO

Background: Computed tomography (CT) is the preferred imaging modality for bone evaluation of the knee, while MRI of the bone is actively being developed. We present three techniques using short-interval delta ultrashort echo time (δUTE), field echo (FE), and FE with high resolution-deep learning reconstruction (HR-DLR) for direct bone MRI. Methods: Knees of healthy volunteers (n = 5, 3 females, 38 ± 17.2 years old) were imaged. CT-like images were generated by averaging images from multiple echoes and inverting. The bone signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were determined. Results: The δUTE depicted a cortical bone with high signal intensity but could not resolve trabeculae. In contrast, both the FE and FE HR-DLR images depicted cortical and trabecular bone with high signal. Quantitatively, while δUTE had a good bone SNR of ~100 and CNR of ~40 for the cortical bone, the SNR for the FE HR-DLR was significantly higher (p < 0.05), at over 400, and CNR at over 200. Conclusions: For 3D rendering of the bone surfaces, the δUTE provided better image contrast and separation of bone from ligaments and tendons than the FE sequences. While there still is no MRI technique that provides a perfect CT-like contrast, continued advancement of MRI techniques may provide benefits for specific use cases.

6.
Radiol Clin North Am ; 62(5): 837-847, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059975

RESUMO

Imaging of rheumatologic diseases has historically been performed using conventional radiography. MRI offers an opportunity for detection of altered marrow signal in early disease that is not visible on other imaging modalities such as radiography, computed tomography, or sonography. This review describes the advantages of current MRI techniques in the diagnosis and treatment monitoring of rheumatologic diseases. In addition, this review discusses novel MRI techniques at high-field magnetic strength which may be deployed in the future to allow for improved imaging resolution and quantitative assessment of both axial and peripheral joints.


Assuntos
Imageamento por Ressonância Magnética , Doenças Reumáticas , Humanos , Imageamento por Ressonância Magnética/métodos , Doenças Reumáticas/diagnóstico por imagem , Reumatologia/métodos
7.
Bioengineering (Basel) ; 11(7)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39061790

RESUMO

Intrinsic cerebrospinal fluid (CSF) dynamics in the brain have been extensively studied, particularly the egress sites of tagged intrinsic CSF in the meninges. Although spinal CSF recirculates within the central nervous system (CNS), we hypothesized that CSF outflows from the lumbar spinal canal. We aimed to visualize and semi-quantify the outflow using non-contrast MRI techniques. We utilized a 3 Tesla clinical MRI with a 16-channel spine coil, employing time-spatial labeling inversion (Time-SLIP) with tag-on and tag-off acquisitions, T2-weighted coronal 2D fluid-attenuated inversion recovery (FLAIR) and T2-weighted coronal 3D centric ky-kz single-shot FSE (cSSFSE). Images were acquired using time-spatial labeling inversion pulse (Time-SLIP) with tag-on and tag-off acquisitions with varying TI periods. Ten healthy volunteers with no known spinal diseases participated. Variations in tagged CSF outflow were observed across different thoracolumbar nerve root segments in all participants. We quantified CSF outflow at all lumbar levels and the psoas region. There was no significant difference among the ROIs for signal intensity. The tagged CSF outflow from the spinal canal is small but demonstrates egress to surrounding tissues. This finding may pave the way for exploring intrathecal drug delivery, understanding of CSF-related pathologies and its potential as a biomarker for peripheral neuropathy and radiculopathy.

8.
J Cosmet Dermatol ; 23(9): 2943-2955, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38807549

RESUMO

BACKGROUND: Androgenetic alopecia (AGA) is a common and chronic problem characterized by hair follicle miniaturization. AIMS: In this study, heat-treated Limosilactobacillus fermentum LM1020 (HT-LM1020) was investigated in human follicle dermal papilla cell (HFDPC), scalp tissue, and clinical trials for patients with AGA. PATIENTS/METHODS: Cell proliferation and the expression of cyclins and cyclin-dependent kinases (CDKs) were measured in HFDPC. The relative gene expression of 5α-reductase and growth factors were investigated in hair scalp. This double-blind, randomized, placebo-controlled clinical trial was conducted over 24 weeks. Primary efficacy was evaluated by measuring hair density, and secondary efficacy was assessed by experts and self-assessment. Changes in the microbiota of the hair scalps were analyzed using 16S metagenome amplicon sequencing. RESULTS: HT-LM1020 promoted cell growth (p < 0.001) and cyclin B1 expression, and it reduced 5α-reductase and induced fibroblast growth factor 7 (FGF7), FGF10, and epithelial growth factor7 (EGF7) (p < 0.001). In the clinical trial, the experimental group demonstrated an increase in hair density from 133.70 to 148.87 n/cm2 at Week 24 (p < 0.001), while also expressing satisfaction with their hair density, reduced hair loss, and hairline. At Week 24, the total ratio of lactic acid bacteria operational taxonomic unit (OTU) in the scalp increased from 6.65% to 26.19%. At the same period, placebo-controlled group decreased Staphylococcus caprae OTU from 77.95% to 14.57% while experimental group decreased from 65.80% to 41.02%. CONCLUSIONS: These present results showed that HT-LM1020 was a co-effector of ingredients for anti-hair loss contributing to cell proliferation and the expression of CDKs.


Assuntos
Alopecia , Limosilactobacillus fermentum , Microbiota , Couro Cabeludo , Humanos , Alopecia/terapia , Alopecia/microbiologia , Alopecia/tratamento farmacológico , Método Duplo-Cego , Couro Cabeludo/microbiologia , Microbiota/efeitos dos fármacos , Adulto , Limosilactobacillus fermentum/fisiologia , Limosilactobacillus fermentum/isolamento & purificação , Masculino , Feminino , Cabelo/microbiologia , Cabelo/crescimento & desenvolvimento , Pessoa de Meia-Idade , Folículo Piloso/microbiologia , Temperatura Alta , Proliferação de Células/efeitos dos fármacos
9.
Jpn J Radiol ; 42(7): 785-797, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38536557

RESUMO

PURPOSE: This study aimed to develop novel non-contrast MR perfusion techniques for assessing micro-vascularity of the foot in human subjects. METHODS: All experiments were performed on a clinical 3 T scanner using arterial spin labeling (ASL). Seven healthy subjects (30-72 years old, 5 males and 2 females) were enrolled and bilateral feet were imaged with tag-on and tag-off alternating inversion recovery spin labeling for determining micro-vascularity. We compared an ASL technique with 1-tag against 4-tag pulses. For perfusion, we determined signal increase ratio (SIR) at varying inversion times (TI) from 0.5 to 2 s. SIR versus TI data were fit to determine perfusion metrics of peak height (PH), time to peak (TTP), full width at half maximum (FWHM), area under the curve (AUC), and apparent blood flow (aBF) in the distal foot and individual toes. Using analysis of variance (ANOVA), effects of tag pulse and region of interest (ROI) on the mean perfusion metrics were assessed. In addition, a 4-tag pulse perfusion experiment was performed on patients with peripheral artery disease (PAD) and Raynaud's disease. RESULTS: Using our MR perfusion techniques, SIR versus TI data showed well-defined leading and trailing edges, with a peak near TI of 0.75-1.0 s and subsiding quickly to near zero by TI of 2 s, particularly when 4-tag pulses were used. When imaged with 4-tag pulse, we found significantly greater values in perfusion metrics, as compared to 1-tag pulse. The patients with PAD and Raynaud's disease showed a reduced or scattered perfusion curves compared to the healthy control. CONCLUSION: MR perfusion imaging of the distal foot shows greater SIR and perfusion metrics with the 4-tag pulse compared to the 1-tag pulse technique. This will likely benefit those with low perfusion due to aging, PAD, diabetic foot, and other vascular diseases.


Assuntos
, Dedos do Pé , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Idoso , Pé/irrigação sanguínea , Pé/diagnóstico por imagem , Dedos do Pé/irrigação sanguínea , Dedos do Pé/diagnóstico por imagem , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Doença de Raynaud/diagnóstico por imagem , Doença de Raynaud/fisiopatologia
10.
Skeletal Radiol ; 53(4): 649-656, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37740079

RESUMO

OBJECTIVE: Cartilage degeneration involves structural, compositional, and biomechanical alterations that may be detected non-invasively using quantitative MRI. The goal of this study was to determine if topographical variation in T1rho values correlates with indentation stiffness and biochemical contents of human patellar cartilage. DESIGN: Cadaveric patellae from unilateral knees of 5 donors with moderate degeneration were imaged at 3-Telsa with spiral chopped magnetization preparation T1rho sequence. Indentation testing was performed, followed by biochemical analyses to determine water and sulfated glycosaminoglycan contents. T1rho values were compared to indentation stiffness, using semi-circular regions of interest (ROIs) of varying sizes at each indentation site. ROIs matching the resected tissues were analyzed, and univariate and multivariate regression analyses were performed to compare T1rho values to biochemical contents. RESULTS: Grossly, superficial degenerative change of the cartilage (i.e., roughened texture and erosion) corresponded with regions of high T1rho values. High T1rho values correlated with low indentation stiffness, and the strength of correlation varied slightly with the ROI size. Spatial variations in T1rho values correlated positively with that of the water content (R2 = 0.10, p < 0.05) and negatively with the variations in the GAG content (R2 = 0.13, p < 0.01). Multivariate correlation (R2 = 0.23, p < 0.01) was stronger than either of the univariate correlations. CONCLUSION: These results demonstrate the sensitivity of T1rho values to spatially varying function and composition of cartilage and that the strength of correlation depends on the method of data analysis and consideration of multiple variables.


Assuntos
Cartilagem Articular , Humanos , Cartilagem Articular/diagnóstico por imagem , Patela/diagnóstico por imagem , Joelho , Imageamento por Ressonância Magnética/métodos , Água
11.
Magn Reson Med Sci ; 23(2): 171-183, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36908171

RESUMO

PURPOSE: Cerebrospinal fluid (CSF) clearance is essential for maintaining a healthy brain and cognition by removal of metabolic waste from the central nervous system. Physical exercise has been shown to improve human health; however, the effect of physical exercise on intrinsic CSF outflow in humans remains unexplored. The purpose of this study was to investigate intrinsic CSF outflow pathways and quantitative metrics of healthy individuals with active and sedentary lifestyles. In addition, the effect of exercise was investigated among the sedentary subjects before and after 3 weeks of physical activity. METHODS: This study was performed on 18 healthy adults with informed consent, using a clinical 3-Tesla MRI scanner. We classified participants into two groups based on reported time spent sitting per day (active group: < 7 hours sitting per day and sedentary group: ≥ 7 hours sitting per day). To elucidate the effect of exercise, sedentary individuals increased their activity to 3.5 hours for 3 weeks. RESULTS: We show that there are two intrinsic CSF egress pathways of the dura mater and lower parasagittal dura (PSD). The adults with an active lifestyle had greater intrinsic CSF outflow metrics than adults with a more sedentary lifestyle. However, after increased physical activity, the sedentary group showed improved CSF outflow metrics. This improvement was particularly notable at the lower PSD, where outflow metrics were highest among the active group. CONCLUSION: Our findings describe the relationship between physical activity and intrinsic CSF outflow and show a potential selective outflow pathway with increasing physical activity in the lower PSD pathway, potentially from the perivascular space or cortical venous subpial space.


Assuntos
Encéfalo , Exercício Físico , Adulto , Humanos , Encéfalo/fisiologia , Imageamento por Ressonância Magnética , Dura-Máter
12.
Magn Reson Med Sci ; 23(2): 193-203, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36948628

RESUMO

PURPOSE: Fatty acid composition of the orbit makes it challenging to achieve complete fat suppression during orbit MR imaging. Implementation of a fat suppression technique capable of suppressing signals from saturated (aliphatic) and unsaturated (olefinic or protons at double-bonded carbon sites) fat would improve the visualization of an optical nerve. Furthermore, the ability to semi-quantify the fractions of aliphatic and olefinic fat may potentially provide valuable information in assessing orbit pathology. METHODS: A phantom study was conducted on various oil samples on a clinical 3 Tesla scanner. The imaging protocol included three 2D fast spin echo (FSE) sequences: in-phase, polarity-altered spectral and spatial selective acquisition (PASTA), and a combination of PASTA with opposed phase in olefinic and aliphatic chemical shift. The results were validated against high-resolution 11.7T NMR and compared with images acquired with spectral attenuated inversion recovery (SPAIR) and chemical shift selective (CHESS) fat suppression techniques. In-vivo data were acquired on eight healthy subjects and were compared with the prior histological studies. RESULTS: PASTA with opposed phase achieved complete suppression of fat signals in the orbits and provided images of well-delineated optical nerves and muscles in all subjects. The olefinic fat fraction in the olive, walnut, and fish oil phantoms at 3T was found to be 5.0%, 11.2%, and 12.8%, respectively, whereas 11.7T NMR provides the following olefinic fat fractions: 6.0% for olive, 11.5% for walnut, and 12.6% for fish oils. For the in-vivo study, on average, olefinic fat accounted for 9.9% ± 3.8% of total fat while the aliphatic fat fraction was 90.1% ± 3.8%, in the normal orbits. CONCLUSION: We have introduced a new fat suppression technique using PASTA with opposed phase and applied it to human orbits. The purposed method achieves an excellent orbital fat suppression and the quantification of aliphatic and olefinic fat signals.


Assuntos
Alcenos , Órbita , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Imagens de Fantasmas , Tecido Adiposo/diagnóstico por imagem
14.
Nat Med ; 29(12): 3120-3126, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37919438

RESUMO

Various types of cellular injection have become a popular and costly treatment option for patients with knee osteoarthritis despite a paucity of literature establishing relative efficacy to each other or corticosteroid injections. Here we aimed to identify the safety and efficacy of cell injections from autologous bone marrow aspirate concentrate, autologous adipose stromal vascular fraction and allogeneic human umbilical cord tissue-derived mesenchymal stromal cells, in comparison to corticosteroid injection (CSI). The study was a phase 2/3, four-arm parallel, multicenter, single-blind, randomized, controlled clinical trial with 480 patients with a diagnosis of knee osteoarthritis (Kellgren-Lawrence II-IV). Participants were randomized to the three different arms with a 3:1 distribution. Arm 1: autologous bone marrow aspirate concentrate (n = 120), CSI (n = 40); arm 2: umbilical cord tissue-derived mesenchymal stromal cells (n = 120), CSI (n = 40); arm 3: stromal vascular fraction (n = 120), CSI (n = 40). The co-primary endpoints were the visual analog scale pain score and Knee injury and Osteoarthritis Outcome Score pain score at 12 months versus baseline. Analyses of our primary endpoints, with 440 patients, revealed that at 1 year post injection, none of the three orthobiologic injections was superior to another, or to the CSI control. In addition, none of the four groups showed a significant change in magnetic resonance imaging osteoarthritis score compared to baseline. No procedure-related serious adverse events were reported during the study period. In summary, this study shows that at 1 year post injection, there was no superior orthobiologic as compared to CSI for knee osteoarthritis. ClinicalTrials.gov Identifier: NCT03818737.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/tratamento farmacológico , Dor/tratamento farmacológico , Dor/etiologia , Método Simples-Cego , Resultado do Tratamento
15.
Sensors (Basel) ; 23(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37766055

RESUMO

Isthmic spondylolysis results in fracture of pars interarticularis of the lumbar spine, found in as many as half of adolescent athletes with persistent low back pain. While computed tomography (CT) is the gold standard for the diagnosis of spondylolysis, the use of ionizing radiation near reproductive organs in young subjects is undesirable. While magnetic resonance imaging (MRI) is preferable, it has lowered sensitivity for detecting the condition. Recently, it has been shown that ultrashort echo time (UTE) MRI can provide markedly improved bone contrast compared to conventional MRI. To take UTE MRI further, we developed supervised deep learning tools to generate (1) CT-like images and (2) saliency maps of fracture probability from UTE MRI, using ex vivo preparation of cadaveric spines. We further compared quantitative metrics of the contrast-to-noise ratio (CNR), mean squared error (MSE), peak signal-to-noise ratio (PSNR), and structural similarity index (SSIM) between UTE MRI (inverted to make the appearance similar to CT) and CT and between CT-like images and CT. Qualitative results demonstrated the feasibility of successfully generating CT-like images from UTE MRI to provide easier interpretability for bone fractures thanks to improved image contrast and CNR. Quantitatively, the mean CNR of bone against defect-filled tissue was 35, 97, and 146 for UTE MRI, CT-like, and CT images, respectively, being significantly higher for CT-like than UTE MRI images. For the image similarity metrics using the CT image as the reference, CT-like images provided a significantly lower mean MSE (0.038 vs. 0.0528), higher mean PSNR (28.6 vs. 16.5), and higher SSIM (0.73 vs. 0.68) compared to UTE MRI images. Additionally, the saliency maps enabled quick detection of the location with probable pars fracture by providing visual cues to the reader. This proof-of-concept study is limited to the data from ex vivo samples, and additional work in human subjects with spondylolysis would be necessary to refine the models for clinical use. Nonetheless, this study shows that the utilization of UTE MRI and deep learning tools could be highly useful for the evaluation of isthmic spondylolysis.


Assuntos
Aprendizado Profundo , Fraturas Ósseas , Espondilólise , Adolescente , Humanos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Espondilólise/diagnóstico por imagem
16.
Food Chem ; 429: 136844, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454617

RESUMO

This study aimed to increase epigallocatechin gallate (EGCG) levels and attenuate the toxicity in Inulabritannica by fermentation using Lactobacillus plantarum SY12. The optimal medium was composed of 10 g of I. britannica, 4 g of xylose, 5 g of soytone, and 5 g of beef extract. The predicted value of EGCG was 237.327 µg/mL. To investigate damage in HepG2 cell lines by I. britannica extracts (IE) or fermented I. britannica extracts (FIE), cell viability, mitochondria membrane potential, the expression of apoptosis and autophagy genes, and chemical composition were measured. FIE increased cell viability, regulation of the gene expression (decreased p53, p62, p-ERK 1/2, and p-p38; increased CDK2 and CDK4) compared with IE. These results were explained by an increase in 1,3-dicaffeoylquinic acid and a decrease in 1-O-caffeoylquinic acid, 1-O-acetylbritannilactone, and ergolide in FIE. In conclusion, these results indicated that fermentation can mitigate the toxicity in I. britannica.


Assuntos
Inula , Lactobacillus plantarum , Animais , Bovinos , Inula/química , Inula/metabolismo , Extratos Vegetais/química , Lactobacillus plantarum/metabolismo , Fermentação
17.
Sci Rep ; 13(1): 12212, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500806

RESUMO

Probiotics are defined as live organisms in the host that contribute to health benefits. Lactobacillus gasseri LM1065, isolated from human breast milk, was investigated for its probiotic properties based on its genome. Draft genome map and de novo assembly were performed using the PacBio RS II system and hierarchical genome assembly process (HGAP). Probiotic properties were determined by the resistance to gastric conditions, adherence ability, enzyme production, safety assessment and mobile genetic elements. The fungistatic effect and inhibition of hyphae transition were studied using the cell-free supernatant (CFS). L. gasseri LM1065 showed high gastric pepsin tolerance and mild tolerance to bile salts. Auto-aggregation and hydrophobicity were measured to be 61.21% and 61.55%, respectively. The adherence to the human intestinal epithelial cells was measured to be 2.02%. Antibiotic-resistance genes and putative virulence genes were not predicted in the genomic analysis, and antibiotic susceptibility was satisfied by the criteria of the European Food Safety Authority. CFS showed a fungistatic effect and suppressed the tricarboxylic acid cycle in Candida albicans (29.02%). CFS also inhibited the transition to true hyphae and damaged the blastoconidia. This study demonstrates the essential properties of this novel probiotic, L. gasseri LM1065, and potential to inhibit vaginal C. albicans infection.


Assuntos
Lactobacillus gasseri , Probióticos , Feminino , Humanos , Lactobacillus gasseri/fisiologia , Intestinos , Antibacterianos/farmacologia , Indústria Alimentícia , Probióticos/farmacologia
18.
Magn Reson Med ; 90(5): 2001-2010, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37288577

RESUMO

PURPOSE: To develop 3D ultrashort-TE (UTE) sequences with tight TE intervals (δTE), allowing for accurate T 2 * $$ {\mathrm{T}}_2^{\ast } $$ mapping of lungs under free breathing. METHODS: We have implemented a four-echo UTE sequence with δTE (< 0.5 ms). A Monte-Carlo simulation was performed to identify an optimal number of echoes that would result in a significant improvement in the accuracy of the T 2 * $$ {\mathrm{T}}_2^{\ast } $$ fit within an acceptable scan time. A validation study was conducted on a phantom with known short T 2 * $$ {\mathrm{T}}_2^{\ast } $$ values (< 5 ms). The scanning protocol included a combination of a standard multi-echo UTE with six echoes (2.2-ms intervals) and a new four-echo UTE (TE < 2 ms) with tight TE intervals δTE. The human imaging was performed at 3 T on 6 adult volunteers. T 2 * $$ {\mathrm{T}}_2^{\ast } $$ mapping was performed with mono-exponential and bi-exponential models. RESULTS: The simulation for the proposed 10-echo acquisition predicted over 2-fold improvement in the accuracy of estimating the short T 2 * $$ {\mathrm{T}}_2^{\ast } $$ compared with the regular six-echo acquisition. In the phantom study, the T 2 * $$ {\mathrm{T}}_2^{\ast } $$ was measured up to three times more accurately compared with standard six-echo UTE. In human lungs, T 2 * $$ {\mathrm{T}}_2^{\ast } $$ maps were successfully obtained from 10 echoes, yielding average values T 2 * $$ {\mathrm{T}}_2^{\ast } $$ = 1.62 ± 0.48 ms for mono-exponential and T 2 s * $$ {\mathrm{T}}_{2s}^{\ast } $$ = 1.00 ± 0.53 ms for bi-exponential models. CONCLUSION: A UTE sequence using δTE was implemented and validated on short T 2 * $$ {\mathrm{T}}_2^{\ast } $$ phantoms. The sequence was successfully applied for lung imaging; the bi-exponential signal model fit for human lung imaging may provide valuable insights into the diseased human lungs.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética , Adulto , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Imagens de Fantasmas , Interpretação de Imagem Assistida por Computador/métodos , Pulmão/diagnóstico por imagem
19.
Jpn J Radiol ; 41(11): 1308-1315, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37247122

RESUMO

PURPOSE: For biochemical evaluation of soft tissues of the knee, T1rho magnetic resonance imaging (MRI) has been proposed. Purpose of this study was to compare three T1rho sequences based on fast advanced spin echo (FASE), ultrashort echo time (UTE), and magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (MAPSS) acquisitions for the knee evaluation. MATERIALS AND METHODS: We developed two T1rho sequences using 3D FASE or 3D radial UTE acquisitions. 3D MAPSS T1rho was provided by the manufacturer. Agarose phantoms with varying concentrations were imaged. Additionally, bilateral knees of asymptomatic subjects were imaged sagittally. T1rho values of the phantoms and 4 regions of interest (ROI) of the knees (i.e., anterior and posterior meniscus, femoral and tibial cartilage) were determined. RESULTS: In phantoms, all T1rho values monotonically decreased with increasing agarose concentration. 3D MAPSS T1rho values of 51, 34, and 38 ms were found for 2, 3, and 4% agarose, respectively, similar to published values on another platform. In the knee, the raw images were detailed with good contrast. Cartilage and meniscus T1rho values varied with the pulse sequence, being the lowest in the 3D UTE T1rho sequence. Comparing different ROIs, menisci generally had lower T1rho values compared to cartilage, as expected in healthy knees. CONCLUSION: We have successfully developed and implemented the new T1rho sequences and validated them using agarose phantoms and volunteer knees. All sequences were optimized to be clinically feasible (~ 5 min or less) and yielded satisfactory image quality and T1rho values consistent with the literature.


Assuntos
Imageamento Tridimensional , Articulação do Joelho , Humanos , Sefarose , Imageamento Tridimensional/métodos , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Tíbia
20.
Eur Spine J ; 32(7): 2358-2367, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37195362

RESUMO

PURPOSE: Using ultrashort echo time (UTE) MRI, we determined prevalence of abnormal cartilaginous endplate (CEP), and the relationship between CEP and disc degeneration in human lumbar spines. MATERIALS AND METHODS: Lumbar spines from 71 cadavers (age 14-74 years) were imaged at 3 T using sagittal UTE and spin echo T2 map sequences. On UTE images, CEP morphology was defined as "normal" with linear high signal intensity or "abnormal" with focal signal loss and/or irregularity. On spin echo images, disc grade and T2 values of the nucleus pulposus (NP) and annulus fibrosus (AF) were determined. 547 CEPs and 284 discs were analysed. Effects of age, sex, and level on CEP morphology, disc grade, and T2 values were determined. Effects of CEP abnormality on disc grade, T2 of NP, and T2 of AF were also determined. RESULTS: Overall prevalence of CEP abnormality was 33% and it tended to increase with older ages (p = 0.08) and at lower spinal levels of L5 than L2 or L3 (p = 0.001). Disc grades were higher and T2 values of the NP were lower in older spines (p < 0.001) and at lower disc level of L4-5 (p < 0.05). We found significant association between CEP and disc degeneration; discs adjacent to abnormal CEPs had high grades (p < 0.01) and lower T2 values of the NP (p < 0.05). CONCLUSION: These results suggest that abnormal CEPs are frequently found, and it associates significantly with disc degeneration, suggesting an insight into pathoetiology of disc degeneration.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Núcleo Pulposo , Humanos , Idoso , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Degeneração do Disco Intervertebral/diagnóstico por imagem , Cartilagem , Imageamento por Ressonância Magnética/métodos , Vértebras Lombares/diagnóstico por imagem
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