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1.
J Magn Reson Imaging ; 60(3): 964-976, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38112331

RESUMO

BACKGROUND: Meningioma subtype is crucial in treatment planning and prognosis delineation, for grade 1 meningiomas. T2 relaxometry could provide detailed microscopic information but is often limited by long scanning times. PURPOSE: To investigate the potential of T2 maps derived from multiple overlapping-echo detachment imaging (MOLED) for predicting meningioma subtypes and Ki-67 index, and to compare the diagnostic efficiency of two different region-of-interest (ROI) placements (whole-tumor and contrast-enhanced, respectively). STUDY TYPE: Prospective. PHANTOM/SUBJECTS: A phantom containing 11 tubes of MnCl2 at different concentrations, eight healthy volunteers, and 75 patients with grade 1 meningioma. FIELD STRENGTH/SEQUENCE: 3 T scanner. MOLED, T2-weighted spin-echo sequence, T2-dark-fluid sequence, and postcontrast T1-weighted gradient echo sequence. ASSESSMENT: Two ROIs were delineated: the whole-tumor area (ROI1) and contrast-enhanced area (ROI2). Histogram parameters were extracted from T2 maps. Meningioma subtypes and Ki-67 index were reviewed by a neuropathologist according to the 2021 classification criteria. STATISTICAL TESTS: Linear regression, Bland-Altman analysis, Pearson's correlation analysis, independent t test, Mann-Whitney U test, Kruskal-Wallis test with Bonferroni correction, and multivariate logistic regression analysis with the P-value significance level of 0.05. RESULTS: The MOLED T2 sequence demonstrated excellent accuracy for phantoms and volunteers (Meandiff = -1.29%, SDdiff = 1.25% and Meandiff = 0.36%, SDdiff = 2.70%, respectively), and good repeatability for volunteers (average coefficient of variance = 1.13%; intraclass correlation coefficient = 0.877). For both ROI1 and ROI2, T2 variance had the highest area under the curves (area under the ROC curve = 0.768 and 0.761, respectively) for meningioma subtyping. There was no significant difference between the two ROIs (P = 0.875). Significant correlations were observed between T2 parameters and Ki-67 index (r = 0.237-0.374). DATA CONCLUSION: MOLED T2 maps can effectively differentiate between meningothelial, fibrous, and transitional meningiomas. Moreover, T2 histogram parameters were significantly correlated with the Ki-67 index. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 2.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Imagens de Fantasmas , Humanos , Meningioma/diagnóstico por imagem , Feminino , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Adulto , Estudos Prospectivos , Idoso , Antígeno Ki-67/metabolismo , Meios de Contraste , Curva ROC , Gradação de Tumores
2.
J Magn Reson Imaging ; 57(5): 1423-1430, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36094322

RESUMO

BACKGROUND: Unsaturated fatty acids (UFAs) of bone marrow play a critical role in osteoporosis. However, it is difficult to resolve the UFA, especially in the presence of trabecular bone, using conventional magnetic resonance spectroscopy (MRS) methods. PURPOSE: To preliminarily compare the bone marrow fatty acids (FAs) composition in the presence of trabecular bone of postmenopausal osteoporosis (PMOP) and healthy controls (HC). STUDY TYPE: Prospective. SUBJECTS: Total thirty-six postmenopausal women were recruited with CT-confirmed PMOP (n = 19) and HC (n = 17). FIELD STRENGTH/SEQUENCES: A 3 T scanner. Localized 2D intermolecular double-quantum coherence-based MRS (iDQC-MRS). ASSESSMENT: In addition to the conventional water and fat peaks, another four crossing peaks of the FAs were well resolved from the L4 vertebral bone marrow using iDQC-MRS technique: allylic methylene (2.0 ppm), terminal methylene (2.2 ppm), diallylic methylene (2.7 ppm), and olefinic (5.3 ppm). The monounsaturated fatty acids (MOFA) and polyunsaturated fatty acids (PUFAs) were then calculated. STATISTICAL TESTS: Differences between PMOP and HC were investigated using the analysis of a t-test, and the relationships were investigated using regression analysis. RESULTS: MOFAs and PUFAs fractions were significantly lower in the PMOP group compared to the HC group. In contrast, the saturated FAs fraction is significantly higher in the PMOP group. Additionally, decreased PUFAs, MOFAs were moderately negatively correlated with the volumetric bone mineral density (vBMD) in the PMOP group. Furthermore, increased SFAs in PMOP were strongly associated with vBMD. DATA CONCLUSION: Using spectra resolution enhanced 2D iDQC-MRS technique, we observed low unsaturated FAs levels in the vertebral bone marrow of the PMOP patients. The reduced unsaturated FAs levels in PMOP may be associated with dysfunction of the balance between osteoblastogenesis and osteoclastogenesis. TECHNICAL EFFICACY STAGE: 1.


Assuntos
Osteoporose Pós-Menopausa , Humanos , Feminino , Estudos Prospectivos , Medula Óssea , Espectroscopia de Ressonância Magnética/métodos , Ácidos Graxos , Ácidos Graxos Insaturados/análise
3.
Acad Radiol ; 31(1): 187-198, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37316368

RESUMO

RATIONALE AND OBJECTIVES: This project aims to investigate the diagnostic performance of multiple overlapping-echo detachment imaging (MOLED) technique-derived transverse relaxation time (T2) maps in predicting progesterone receptor (PR) and S100 expression in meningiomas. MATERIALS AND METHODS: 63 meningioma patients were enrolled from October 2021 to August 2022, who underwent a complete routine magnetic resonance imaging and T2 MOLED, which can characterize the whole brain transverse relaxation time within 32 seconds in a single scan. After the surgical resection of meningiomas, the expression levels of PR and S100 were determined by an experienced pathologist using immunohistochemistry techniques. Histogram analysis was performed in tumor parenchyma based on the parametric maps. Independent t test and Mann-Whitney U test were applied for the comparison of histogram parameters between different groups, with a significance level of P < .05. Logistic regression and receiver operating characteristic (ROC) analysis with 95% confidence interval were conducted for the diagnostic efficiency evaluation. RESULTS: PR-positive group had significantly elevated T2 histogram parameters (P = .001-.049) compared to the PR-negative group. The multivariate logistic regression model with T2 showed the highest area under the ROC curve (AUC) for predicting PR expression (AUC=0.818). Additionally, the multivariate model also had the best diagnostic performance for predicting meningioma S100 expression (AUC=0.768). CONCLUSION: The MOLED technique-derived T2 maps can distinguish PR and S100 status in meningiomas preoperatively.


Assuntos
Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/diagnóstico por imagem , Meningioma/cirurgia , Meningioma/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Prospectivos , Receptores de Progesterona , Imageamento por Ressonância Magnética/métodos , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Estudos Retrospectivos
4.
Acad Radiol ; 31(6): 2488-2500, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38142175

RESUMO

RATIONALE AND OBJECTIVES: Stroke patients commonly face challenges during magnetic resonance imaging (MRI) examinations due to involuntary movements. This study aims to overcome these challenges by utilizing multiple overlapping-echo detachment (MOLED) quantitative technology. Through this technology, we also seek to detect microstructural changes of the normal-appearing corticospinal tract (NA-CST) in subacute-chronic stroke patients. MATERIALS AND METHODS: 79 patients underwent 3.0 T MRI scans, including routine scans and MOLED technique. A deep learning network was utilized for image reconstruction, and the accuracy, reliability, and resistance to motion of the MOLED technique were validated on phantoms and volunteers. Subsequently, we assessed motor dysfunction severity, ischemic lesion volume, T2 values of the bilateral NA-CST, and the T2 ratio (rT2) between the ipsilesional and contralesional NA-CST in patients. RESULTS: The MOLED technique showed high accuracy (P < 0.001) and excellent repeatability, with a mean coefficient of variation (CoV) of 1.11%. It provided reliable quantitative results even under head movement, with a mean difference (Meandiff)= 0.28% and a standard deviation difference (SDdiff)= 1.34%. Additionally, the T2 value of the ipsilesional NA-CST was significantly higher than contralesional side (P < 0.001), and a positive correlation was observed between rT2 and the severity of motor dysfunction (rs =0.575, P < 0.001). Furthermore, rT2 successfully predicted post-stroke motor impairment, with an area under the curve (AUC) was 0.883. CONCLUSION: The MOLED technique offers significant advantages for quantitatively imaging stroke patients with involuntary movements. Additionally, T2 mapping from MOLED can detect microstructural changes in the NA-CST, potentially aiding in monitoring stroke-induced motor impairment.


Assuntos
Imageamento por Ressonância Magnética , Tratos Piramidais , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Tratos Piramidais/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/complicações , Imageamento por Ressonância Magnética/métodos , Idoso , Reprodutibilidade dos Testes , Doença Crônica , Adulto , Movimento (Física) , Imagens de Fantasmas , Aprendizado Profundo
5.
Aging (Albany NY) ; 14(8): 3446-3463, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35452413

RESUMO

Lymphoma is accompanied by the impairment of multiple immune functions. Cytokines play an important role in a variety of immune-related functions and affect the tumor microenvironment. However, the exact regulatory mechanisms between them remain unclear. This study aimed to explore the cytokines expression and function in Hodgkin's lymphoma (HL), diffuse large B-cell lymphoma (DLBCL), and mantle cell lymphoma (MCL). We performed a transcriptome integration analysis of 14 lymphoma datasets including 240 Hodgkin's lymphoma, 891 diffuse large B-cell lymphoma, 216 mantle cell lymphoma, and 64 health samples. The results showed that multiple immune functions and signal pathway damage were shared by all three types of lymphoma, and these functions were related to cytokines. Furthermore, through co-expression network and functional interaction network analysis, we identified CXCL14 as a key regulator and it affects cell chemotaxis and migration functions. The functional experiment showed that CXCL14 knockdown inhibited cell migration in MCL cell lines. This study suggested that high expression of CXCL14 may aggravate MCL via promoting cell migration. Our findings provide novel insights into the biology of this disease and would be helpful for the pathogenesis study and drug discovery of lymphomas.


Assuntos
Doença de Hodgkin , Linfoma Difuso de Grandes Células B , Linfoma de Célula do Manto , Movimento Celular/genética , Quimiocinas CXC/genética , Citocinas , Humanos , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Célula do Manto/genética , Microambiente Tumoral/genética
6.
Water Environ Res ; 93(8): 1370-1380, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33528855

RESUMO

The effect of pH regulation in phase I on hydrolysis and acidogenesis rate, metabolites production, microbial community, and the overall energy recovery efficiency during two-phase anaerobic digestion (AD) of food waste (FW) was investigated. pH strongly affected the acidogenesis rate and the yield of the fermentation products. The highest acidogenesis efficiency (60.4%) and total volatile fatty acids (VFA)/ethanol concentration (12.4 g/L) were obtained at pH 8 during phase I. Microbial community analysis revealed that Clostridium IV was enriched at pH 8, relating to the accumulation of butyrate. Also, Clostridium sensu stricto played a crucial role in hydrogen production and was abundant at pH 6, resulting in the highest hydrogen yield (212.2 ml/g VS). In phase II, the highest cumulative methane yield (412.6 ml/g VS) was obtained at pH 8. By considering the hydrogen and methane production stages, the highest energy yield (22.8 kJ/g VS, corresponding to a 76.4% recovery efficiency) was generated at pH 8, which indicates that pH 8 was optimal for energy recovery during two-phase AD of FW. Overall, the results demonstrated the possibility of increasing the energy recovery from FW by regulating the pH in the hydrolysis/acidogenesis phase based on the two-phase AD system. PRACTITIONER POINTS: pH 8 was suitable for hydrolysis, acidogenesis, and methanogenesis. High hydrogen yields were obtained at pH 5-8 (about 200 ml/d). Clostridium sensu stricto might have played a crucial role in hydrogen production. High methane production (about 400 ml/g VS) was obtained at pH 7-9. pH 8 was optimal for energy recovery from FW with an efficiency of 76.4% (22.8 kJ/g VS).


Assuntos
Alimentos , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Concentração de Íons de Hidrogênio
7.
Am J Transl Res ; 12(8): 4757-4771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32913548

RESUMO

Ischemia reperfusion (I/R) injury, an inevitable event accompanying heart transplantation, is the primary factor leading to organ failure and graft rejection. In order to prevent I/R injury, we established murine heart transplantation model with I/R and cell culture system to determine whether ß-catenin is a mediate factor in preventing I/R injury in heart transplantation. After successfully established heterotopic heart transplantation mice model, the I/R injury was induced, and two dynamic temporal were studied during different I/R phases. With the increase of ischemia and reperfusion time, heart damage was more severe. In the initial study, we observed that ß-catenin was significantly decreased, while ROCK1 and PTEN increased during the perfusion phase from day 0 to day 1, and remain the same level until 3 days later. The similar pattern that ß-catenin was down-regulated while ROCK1 and PTEN were up-regulated was also observed in the dynamic temporal ischemia study. To further investigate the role of ß-catenin signaling in I/R injury in vitro, ß-catenin over-expressing plasmid was transfected into HL-1 cells, a cardiac cell line. We noted that ß-catenin over-expressing cardiomyocytes showed decreased ROCK1/PTEN expression both at mRNA and protein levels. In addition, cobalt dichloride (CoCl2) -induced oxidative stress model was further established to mimic cardiac I/R injury. We observed that CoCl2-induced activation of ROCK1/PTEN signaling pathway were attenuated by transient transfection of a ß-catenin over-expressing plasmid. Taken together, our results suggest that cardiac transplant induced IR injury is closely associated with the down-regulation of ß-catenin and up-regulation of ROCK1 and PTEN expression.

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