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1.
Plant Cell Physiol ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619117

RESUMO

Verticillium dahliae is a kind of pathogenic fungus that brings about wilt disease and great losses in cotton. The molecular mechanism of the effectors in V. dahliae regulating cotton immunity remains largely unknown. Here we identified an effector of V. dahliae, VdPHB1, whose gene expression is highly induced by infection. VdPHB1 protein is localized in the intercellular space of cotton plants. Knockout VdPHB1 gene in V. dahliae had no effect on pathogen growth, but decreased the virulence in cotton. VdPHB1 ectopically expressed Arabidopsis plants were growth-inhibited and significantly susceptible to V. dahliae. Further, VdPHB1 interacted with the type II metacaspase GhMC4. GhMC4 gene silenced cotton plants were more sensitive to V. dahliae with reduced expressions of pathogen defense-related and programmed cell death genes. The accumulation of GhMC4 protein were concurrently repressed when VdPHB1 protein expressed during infection. In summary, these results revealed a novel molecular mechanism of virulence regulation that the secreted effector VdPHB1 represses the activity of cysteine protease for helping V. dahliae infection in cotton.

2.
NMR Biomed ; : e5176, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884131

RESUMO

Early tumor response prediction can help avoid overtreatment with unnecessary chemotherapy sessions. It is important to determine whether multiple apparent diffusion coefficient indices (S index, ADC-diff) are effective in the early prediction of pathological response to neoadjuvant chemotherapy (NAC) in breast cancer (BC). Patients with stage II and III BCs who underwent T1WI, diffusion-weighted imaging (DWI), and dynamic contrast-enhanced MRI using a 3 T system were included. They were divided into two groups: major histological responders (MHRs, Miller-Payne G4/5) and nonmajor histological responders (nMHRs, Miller-Payne G1-3). Three b values were used for DWI to derive the S index; ADC-diff values were obtained using b = 0 and 1000 s/mm2. The different interquartile ranges of percentile S-index and ADC-diff values after treatment were calculated and compared. The assessment was performed at baseline and after two and four NAC cycles. A total of 59 patients were evaluated. There are some correlations of interquartile ranges of S-index parameters and ADC-diff values with histopathological prognostic factors (such as estrogen receptor and human epidermal growth factor receptor 2 expression, all p < 0.05), but no significant differences were found in some other interquartile ranges of S-index parameters or ADC-diff values between progesterone receptor positive and negative or for Ki-67 tumors (all P > 0.05). No differences were found in the dynamic contrast-enhanced MRI characteristics between the two groups. HER-2 expression and kurtosis of the S-index distribution were screened out as independent risk factors for predicting MHR group (p < 0.05, area under the curve (AUC) = 0.811) before NAC. After early NAC (two cycles), only the 10th percentile S index was statistically significant between the two groups (p < 0.05, AUC = 0.714). No significant differences were found in ADC-diff value at any time point of NAC between the two groups (P > 0.1). These findings demonstrate that the S-index value may be used as an early predictor of pathological response to NAC in BC; the value of ADC-diff as an imaging biomarker of NAC needs to be further confirmed by ongoing multicenter prospective trials.

3.
J Magn Reson Imaging ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38708838

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is associated with increased, and early cardiovascular disease risk. Changes in hemodynamics within the left ventricle (LV) respond to cardiac remodeling. The LV hemodynamics in nondialysis CKD patients are not clearly understood. PURPOSE: To use four-dimensional blood flow MRI (4D flow MRI) to explore changes in LV kinetic energy (KE) and the relationship between LV KE and LV remodeling in CKD patients. STUDY TYPE: Retrospective. POPULATION: 98 predialysis CKD patients (Stage 3: n = 21, stage 4: n = 21, and stage 5: n = 56) and 16 age- and sex-matched healthy controls. FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession (SSFP) cine sequence, 4D flow MRI with a fast field echo sequence, T1 mapping with a modified Look-Locker SSFP sequence, and T2 mapping with a gradient recalled and spin echo sequence. ASSESSMENT: Demographic characteristics (age, sex, height, weight, blood pressure, heart rate, aortic regurgitation, and mitral regurgitation) and laboratory data (eGFR, Creatinine, hemoglobin, ferritin, transferrin saturation, potassium, and carbon dioxide bonding capacity) were extracted from patient records. Myocardial T1, T2, LV ejection fraction, end diastolic volume (EDV), end systolic volume, LV flow components (direct flow, delayed ejection, retained inflow, and residual volume) and KE parameters (peak systolic, systolic, diastolic, peak E-wave, peak A-wave, E/A ratio, and global) were assessed. The KE parameters were normalized to EDV (KEiEDV). Parameters were compared between disease stage in CKD patients, and between CKD patients and healthy controls. STATISTICAL TESTS: Differences in clinical and imaging parameters between groups were compared using one-way ANOVA, Kruskal Walls and Mann-Whitney U tests, chi-square test, and Fisher's exact test. Pearson or Spearman's correlation coefficients and multiple linear regression analysis were used to compare the correlation between LV KE and other clinical and functional parameters. A P-value of <0.05 was considered significant. RESULTS: Compared with healthy controls, peak systolic (24.76 ± 5.40 µJ/mL vs. 31.86 ± 13.18 µJ/mL), systolic (11.62 ± 2.29 µJ/mL vs. 15.27 ± 5.10 µJ/mL), diastolic (7.95 ± 1.92 µJ/mL vs. 13.33 ± 5.15 µJ/mL), peak A-wave (15.95 ± 4.86 µJ/mL vs. 31.98 ± 14.51 µJ/mL), and global KEiEDV (9.40 ± 1.64 µJ/mL vs. 14.02 ± 4.14 µJ/mL) were significantly increased and the KEiEDV E/A ratio (1.16 ± 0.67 vs. 0.69 ± 0.53) was significantly decreased in CKD patients. As the CKD stage progressed, both diastolic KEiEDV (10.45 ± 4.30 µJ/mL vs. 12.28 ± 4.85 µJ/mL vs. 14.80 ± 5.06 µJ/mL) and peak E-wave KEiEDV (15.30 ± 7.06 µJ/mL vs. 14.69 ± 8.20 µJ/mL vs. 19.33 ± 8.29 µJ/mL) increased significantly. In multiple regression analysis, global KEiEDV (ß* = 0.505; ß* = 0.328), and proportion of direct flow (ß* = -0.376; ß* = -0.410) demonstrated an independent association with T1 and T2 times. DATA CONCLUSION: 4D flow MRI-derived LV KE parameters show altered LV adaptations in CKD patients and correlate independently with T1 and T2 mapping that may represent myocardial fibrosis and edema. TECHNICAL EFFICACY: Stage 3.

4.
Eur Radiol ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38334760

RESUMO

BACKGROUND: Increasing attention has been given to the peritumoral region. However, conflicting findings have been reported regarding the relationship between peritumoral region features on MRI and the prognosis of breast cancer. PURPOSE: To evaluate the relationship between peritumoral region features on MRI and prognosis of breast cancer. MATERIALS AND METHODS: A retrospective meta-analysis of observational studies comparing either qualitative or quantitative assessments of peritumoral MRI features on breast cancer with poor prognosis and control subjects was performed for studies published till October 2022. Pooled odds ratios (ORs) or standardized mean differences and 95% confidence intervals (CIs) were estimated by using random-effects models. The heterogeneity across the studies was measured using the statistic I2. Sensitivity analyses were conducted to test this association according to different study characteristics. RESULTS: Twenty-four studies comprising 1853 breast cancers of poor prognosis and 2590 control participants were included in the analysis. Peritumoral edema was associated with non-luminal breast cancers (OR=3.56; 95%CI: 2.17, 5.83; p=.000), high expression of the Ki-67 index (OR=3.70; 95%CI: 2.41, 5.70; p =.000), high histological grade (OR=5.85; 95%CI: 3.89, 8.80; p=.000), lymph node metastasis (OR=2.83; 95%CI: 1.71, 4.67; p=.000), negative expression of HR (OR=3.15; 95%CI: 2.03, 4.88; p=.000), and lymphovascular invasion (OR=1.72; 95%CI: 1.28, 2.30; p=.000). The adjacent vessel sign was associated with greater odds of breast cancer with poor prognosis (OR=2.02; 95%CI: 1.68, 2.44; p=.000). Additionally, breast cancers with poor prognosis had higher peritumor-tumor ADC ratio (SMD=0.67; 95%CI: 0.54, 0.79; p=.000) and peritumoral ADCmean (SMD=0.29; 95%CI: 0.15, 0.42; p=.000). A peritumoral region of 2-20 mm away from the margin of the tumor is recommended. CONCLUSION: The presence of peritumoral edema and adjacent vessel signs, higher peritumor-tumor ADC ratio, and peritumoral ADCmean were significantly correlated with poor prognosis of breast cancer. CLINICAL RELEVANCE STATEMENT: MRI features of the peritumoral region can be used as a non-invasive index for the prognostic evaluation of invasive breast cancer. KEY POINTS: • Peritumoral edema was positively associated with non-luminal breast cancer, high expression of the Ki-67 index, high histological grade, lymph node metastasis, negative expression of HR, and lymphovascular invasion. • The adjacent vessel sign was associated with greater odds of breast cancers with poor prognosis. • Breast cancers with poor prognosis had higher peritumor-tumor ADC ratio and peritumoral ADCmean.

5.
Analyst ; 149(5): 1473-1480, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38294023

RESUMO

Phosphorescence analyses have attracted broad attention due to their remarkable merits of the elimination of auto-fluorescence and scattering light. However, it remains a great challenge to develop novel materials with uniform size and morphology, stability, long lifetime, and aqueous-phase room temperature phosphorescence (RTP) characteristics. Herein, monodisperse and uniform RTP nanobeads were fabricated by an in situ covalent hybridization of carbon dots (CDs) and dendritic mesoporous silicon nanoparticles (DMSNs) via silane hydrolysis. The formation of Si-O-C and Si-C/N covalent bonds is beneficial for the fixation of vibrations and rotations of the luminescent centers. Specially, the nanopores of DMSNs provide a confined area that can isolate the triplet state of CDs from water and oxygen and thus ensure the occurrence of aqueous-phase RTP with an ultra-long lifetime of 1.195 s (seen by the naked eye up to 9 seconds). Through surface modifying folic acid (FA), CDs@DMSNs can serve as a probe to distinguish different cell lines that feature varying FA receptor expression levels. In addition, taking MCF-7 as the model, highly sensitive and quantitative detection (linear range: 103-106 cells per mL) has been achieved via an RTP probe. Furthermore, their potential applications in cellular and in vivo time-gated phosphorescence imaging have been proposed and demonstrated, respectively. This work would provide a new route to design CD-based RTP composites and promote their further applications in the medical and biological fields.


Assuntos
Dióxido de Silício , Silício , Carbono , Linhagem Celular , Medições Luminescentes
6.
Plant Biotechnol J ; 21(11): 2374-2388, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37596974

RESUMO

Ethylene plays an essential role in the development of cotton fibres. Ethylene biosynthesis in plants is elaborately regulated by the activities of key enzymes, 1-aminocyclopropane-1-carboxylate oxidase (ACO) and 1-aminocyclopropane-1-carboxylate synthase (ACS); however, the potential mechanism of post-translational modification of ACO and ACS to control ethylene synthesis in cotton fibres remains unclear. Here, we identify an E3 ubiquitin ligase, GhXB38D, that regulates ethylene biosynthesis during fibre elongation in cotton. GhXB38D gene is highly expressed in cotton fibres during the rapid elongation stage. Suppressing GhXB38D expression in cotton significantly enhanced fibre elongation and length, accompanied by the up-regulation of genes associated with ethylene signalling and fibre elongation. We demonstrated that GhXB38D interacts with the ethylene biosynthesis enzymes GhACS4 and GhACO1 in elongating fibres and specifically mediates their ubiquitination and degradation. The inhibition of GhXB38D gene expression increased the stability of GhACS4 and GhACO1 proteins in cotton fibres and ovules, resulting in an elevated concentration of ethylene. Our findings highlight the role of GhXB38D as a regulator of ethylene synthesis by ubiquitinating ACS4 and ACO1 proteins and modulating their stability. GhXB38D acts as a negative regulator of fibre elongation and serves as a potential target for enhancing cotton fibre yield and quality through gene editing strategy.


Assuntos
Fibra de Algodão , Etilenos , Ubiquitina-Proteína Ligases/genética , Ubiquitinação , Regulação da Expressão Gênica de Plantas , Gossypium/genética
7.
BMC Cancer ; 23(1): 1026, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37875815

RESUMO

BACKGROUND: Noninvasive and precise methods to estimate treatment response and identify hepatocellular carcinoma (HCC) patients who could benefit from transarterial chemoembolization (TACE) are urgently required. The present study aimed to investigate the ability of intratumoral and peritumoral radiomics based on contrast-enhanced magnetic resonance imaging (CE-MRI) to preoperatively predict tumor response to TACE in HCC patients. METHODS: A total of 138 patients with HCC who received TACE were retrospectively included and randomly divided into training and validation cohorts at a ratio of 7:3. Total 1206 radiomics features were extracted from arterial, venous, and delayed phases images. The inter- and intraclass correlation coefficients, the spearman's rank correlation test, and the gradient boosting decision tree algorithm were used for radiomics feature selection. Radiomics models on intratumoral region (TR) and peritumoral region (PTR) (3 mm, 5 mm, and 10 mm) were established using logistic regression. Three integrated radiomics models, including intratumoral and peritumoral region (T-PTR) (3 mm), T-PTR (5 mm), and T-PTR (10 mm) models, were constructed using TR and PTR radiomics scores. A clinical-radiological model and a combined model incorporating the optimal radiomics score and selected clinical-radiological predictors were constructed, and the combined model was presented as a nomogram. The discrimination, calibration, and clinical utilities were evaluated by receiver operating characteristic curve, calibration curve, and decision curve analysis, respectively. RESULTS: The T-PTR radiomics models performed better than the TR and PTR models, and the T-PTR (3 mm) radiomics model demonstrated preferable performance with the AUCs of 0.884 (95%CI, 0.821-0.936) and 0.911 (95%CI, 0.825-0.975) in both training and validation cohorts. The T-PTR (3 mm) radiomics score, alkaline phosphatase, tumor size, and satellite nodule were fused to construct a combined nomogram. The combined nomogram [AUC: 0.910 (95%CI, 0.854-0.958) and 0.918 (95%CI, 0.831-0.986)] outperformed the clinical-radiological model [AUC: 0.789 (95%CI, 0.709-0.863) and 0.782 (95%CI, 0.660-0.902)] in the both cohorts and achieved good calibration capability and clinical utility. CONCLUSIONS: CE-MRI-based intratumoral and peritumoral radiomics approach can provide an effective tool for the precise and individualized estimation of treatment response for HCC patients treated with TACE.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Estudos Retrospectivos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética
8.
J Magn Reson Imaging ; 57(2): 493-505, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35735273

RESUMO

BACKGROUND: Microsatellite instability (MSI), caused by mismatch repair (MMR) protein defects that lead to uncorrectable mismatch bases, results in the accumulation of gene mutations and ultimately to tumors. Preoperative prediction of MSI can provide a basis for personalized and precise treatment of endometrial cancer (EC) patients. PURPOSE: To investigate amide proton transfer weighting (APTw) imaging combined with intravoxel incoherent motion (IVIM) in the assessment of MSI in EC. STUDY TYPE: Retrospective. POPULATION: A total of 71 patients with EC (12 classified as the MSI group and 22 as the microsatellite stabilization [MSS] group after entering and leaving the group standard). FIELD STRENGTH/SEQUENCE: A 3.0 T/IVIM, diffusion-weighted imaging (DWI) and APTw. ASSESSMENT: Amide proton transfer (APT) value, apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) were calculated and compared between MSI and MSS groups. STATISTICAL TESTS: The Kendall's W test; Mann-Whitney U-test; Chi-square test or Fisher's exact test; logistic regression analysis; Area under the receiver operating characteristic (ROC) curve (AUC); The Delong test; Pearson or Spearman correlation coefficients. The significance threshold was set at P < 0.05. RESULTS: APT and D* values of the MSI group were significantly higher than those of the MSS group. While ADC, D, and f values in the MSI group were significantly lower than those in the MSS group. The multivariate analysis revealed that only APT and D* values were independent predictors to evaluate the MSI status. And the ROC curves indicated that the combination of APT and D* values could distinguish the MSI status of EC with the highest diagnostic efficacy (AUC = 0.973), even without significant difference to those by APT (AUC = 0.894) or D* (AUC = 0.920) value separately (P = 0.149 and 0.078, respectively). CONCLUSION: Combination of APTw and IVIM imaging may serve as an effective noninvasive method for clinical assessment of MSI in EC. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias do Endométrio , Prótons , Feminino , Humanos , Instabilidade de Microssatélites , Amidas , Estudos Retrospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/genética , Movimento (Física)
9.
BMC Cardiovasc Disord ; 23(1): 42, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36690952

RESUMO

BACKGROUND: A subset of patients with hypertrophic cardiomyopathy (HCM) will experience adverse clinical events such as heart failure (HF), cardiovascular death, and new-onset atrial fibrillation (AF). Current risk stratification methods are imperfect and limit the identification of patients at high risk for HCM. This study aimed to evaluate the role of cardiac magnetic resonance (CMR)-derived left atrial strain parameters in the occurrence of adverse clinical events in patients with HCM. METHODS: Left atrial (LA) structural, functional, and strain parameters were evaluated in 99 patients with HCM and compared with 89 age-, sex-, and BMI-matched control subjects. LA strain parameters were derived from CMR two- and four-chamber cine images by a semiautomatic method. LA strain parameters include global longitudinal strain (GLS) and global circumferential strain (GCS). The LA GLS includes reservoir strain (GLS reservoir), conduit strain (GLS conduit), and booster strain (GLS booster). Three LA GLS strain rate (SR) parameters were derived: SR reservoir, SR conduit, and SR booster. The primary endpoint was set as a composite of adverse clinical events, including SCD, new-onset or worsening to hospitalized HF, new-onset AF, thromboembolic events, and fatal ventricular arrhythmias. RESULTS: LA GLS, GLS SR and GCS were impaired in HCM patients compared to control subjects (all p < 0.001). After a mean follow-up of 37.94 ± 23.69 months, 18 HCM patients reached the primary endpoint. LA GLS, GLS SR, and GCS were significantly lower in HCM patients with adverse clinical events than in those without adverse clinical events (all p < 0.05). In stepwise multiple Cox regression analysis, LV SV, LA diameter, pre-contraction LAV (LAV pre-ac), passive LA ejection fraction (EF), and LA GLS booster were all independent determinants of adverse clinical events. LA GLS booster ≤ 8.9% was the strongest determinant (HR = 8.9 [95%CI (1.951, 40.933)], p = 0.005). Finally, LA GLS booster provided predictive adverse clinical events value (AUC = 0.86 [95%CI 0.77-0.98]) that exceeded traditional outcome predictors. CONCLUSION: LA strain assessment, a measure of LA function, provides additional predictive information for established predictors of HCM patients. LA GLS booster was independently associated with adverse clinical events in patients with HCM.


Assuntos
Fibrilação Atrial , Cardiomiopatia Hipertrófica , Insuficiência Cardíaca , Humanos , Átrios do Coração , Volume Sistólico , Imagem Cinética por Ressonância Magnética , Função Ventricular Esquerda
10.
Chem Eng J ; 468: 143616, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37251501

RESUMO

Förster or fluorescence resonance energy transfer (FRET) enables to probe biomolecular interactions, thus playing a vital role in bioassays. However, conventional FRET platforms suffer from limited sensitivity due to the low FRET efficiency and poor anti-interference of existing FRET pairs. Here we report a NIR-II (1000-1700 nm) FRET platform with extremely high FRET efficiency and exceptional anti-interference capability. This NIR-II FRET platform is established based on a pair of lanthanides downshifting nanoparticles (DSNPs) by employing Nd3+ doped DSNPs as an energy donor and Yb3+ doped DSNPs as an energy acceptor. The maximum FRET efficiency of this well-engineered NIR-II FRET platform reaches up to 92.2%, which is much higher than most commonly used ones. Owing to the all-NIR advantage (λex = 808 nm, λem = 1064 nm), this highly efficient NIR-II FRET platform exhibits extraordinary anti-interference in whole blood, and thus enabling background-free homogeneous detection of SARS-CoV-2 neutralizing antibodies in clinical whole blood sample with high sensitivity (limit of detection = 0.5 µg/mL) and specificity. This work opens up new opportunities for realizing highly sensitive detection of various biomarkers in biological samples with severe background interference.

11.
Plant Physiol ; 187(3): 1779-1794, 2021 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-34618046

RESUMO

Plants exhibit remarkable developmental plasticity, enabling them to adapt to adverse environmental conditions such as low nitrogen (N) in the soil. Brassinosteroids (BRs) promote root foraging for nutrients under mild N deficiency, but the crosstalk between the BR- and N-signaling pathways in the regulation of root growth remains largely unknown. Here, we show that CALMODULIN-LIKE-38 (CML38), a calmodulin-like protein, specifically interacts with the PEP1 RECEPTOR 2 (PEPR2), and negatively regulates root elongation in Arabidopsis (Arabidopsis thaliana) in response to low nitrate (LN). CML38 and PEPR2 are transcriptionally induced by treatments of exogenous nitrate and BR. Compared with Col-0, the single mutants cml38 and pepr2 and the double mutant cml38 pepr2 displayed enhanced primary root growth and produced more lateral roots under LN. This is consistent with their higher nitrate absorption abilities, and their stronger expression of nitrate assimilation genes. Furthermore, CML38 and PEPR2 regulate common downstream genes related to BR signaling, and they have positive roles in BR signaling. Low N facilitated BR signal transmission in Col-0 and CML38- or PEPR2-overexpressing plants, but not in the cml38 and pepr2 mutants. Taken together, our results illustrate a mechanism by which CML38 interacts with PEPR2 to integrate LN and BR signals for coordinating root development to prevent quick depletion of N resources in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Brassinosteroides/metabolismo , Calmodulina/genética , Nitratos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Calmodulina/metabolismo , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Proteínas Serina-Treonina Quinases/metabolismo
12.
NMR Biomed ; 35(6): e4676, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35043481

RESUMO

In the current study, we propose a single-voxel (SV) magnetic resonance spectroscopy (MRS) pulse sequence, based on intermolecular double-quantum coherence (iDQC), for in vivo specific assessment of brown adipose tissue (BAT) at 3 T. The multilocular adipocyte, present in BAT, typically contains a large number of small lipid droplets surrounded by abundant intracellular water, while the monolocular adipocyte, present in white adipose tissue (WAT), accommodates only a single large lipid droplet with much less water content. The SV-iDQC sequence probes the spatial correlation between water and fat spins at a distance of about the size of an adipocyte, thus can be used for assessment of BAT, even when mixed with WAT and/or muscle tissues. This sequence for measurement of water-to-fat (water-fat) iDQC signals was tested on phantoms and mouse BAT and WAT tissues. It was then used to differentiate adipose tissues in the supraclavicular and subcutaneous regions of healthy youth human volunteers (n = 6). Phantom results with water-fat emulsions demonstrated enhanced water-fat iDQC signal with increased voxel size, increased energy level of emulsification, or increased distribution balance of water and fat spins. The animal tissue experiments resulted in obvious water-fat iDQC signal in mouse BAT, while this signal was almost absent in the WAT spectrum. The optimal choice of the dipolar coupling distance for the observation was approximately 100 µm, as tested on both emulsion phantom and animal tissue. The water-fat iDQC signals observed in the supraclavicular adipose tissues were higher than in the subcutaneous adipose tissues in healthy young volunteers (0.43 ± 0.36 vs. 0.10 ± 0.06, p = 0.06). It was concluded that the iDQC-based sequence has potential for assessment of mouse and human BAT at 3 T, which is of interest for clinical research and the diagnosis of obesity and associated diseases.


Assuntos
Tecido Adiposo Marrom , Tecido Adiposo Branco , Tecido Adiposo Marrom/diagnóstico por imagem , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/diagnóstico por imagem , Adolescente , Animais , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Água
13.
Neurol Sci ; 43(11): 6433-6440, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35971044

RESUMO

Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) is a rare autosomal dominant disorder caused by mutations in the colony-stimulating factor 1 receptor (CSF1R) gene. As of 2022, more than 100 different CSF1R mutations were reported in patients with CSF1R-related leukoencephalopathy. In this case report, we describe ALSP in a previously healthy 46-year-old woman who presented with memory impairment, poor interpersonal behavior, and decreased verbal fluency. Brain magnetic resonance imaging (MRI) showed confluent white matter changes and atrophy of the corpus callosum. Whole-exome sequencing identified a novel splice-site mutation (C.1858 + 5G > A) in intron 13 of the CSF1R gene, resulting in an intron 12 retention and an exon 13 deletion of CSF1R mRNA.


Assuntos
Leucoencefalopatias , Feminino , Humanos , Pessoa de Meia-Idade , Encéfalo/diagnóstico por imagem , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/genética , Imageamento por Ressonância Magnética , Mutação/genética , Neuroglia , Idade de Início
14.
Acta Radiol ; 63(12): 1634-1642, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34860127

RESUMO

BACKGROUND: Strain analysis has become commonly used in clinical practice in various heart diseases. PURPOSE: To explore whether late gadolinium enhancement (LGE)-negative areas with coronary artery chronic total occlusion (CTO) appear normal when analyzed for longitudinal strain using cardiac magnetic resonance (CMR) imaging. MATERIAL AND METHODS: A total of 16 patients and 31 healthy controls who underwent 1.5-T MR at our hospital between January 2015 and July 2017 were included in the study. The LGE-CMR of patients with CTO was negative. Left ventricular functional parameters, segmental longitudinal strain/strain rate, and perfusion parameters were measured using CVI42 software. RESULTS: For myocardial segments supplied by CTO vessels, systolic longitudinal strain rate (SLSR)was significantly lower than that of healthy controls, and diastolic longitudinal strain rate (DLSR) was significantly higher (1.19 1/s vs. 1.02 1/s; P = 0.018). Moreover, longitudinal strain (LS), SLSR, and DLSR did not differ between good and poor collateral circulation. Perfusion index of CTO territory segments was lower than non-CTO territory segments (0.20 vs. 0.22; P = 0.027). No correlation was found between longitudinal strain parameters and perfusion parameters. CONCLUSION: Although LGE-CMR was negative in patients with CTO, the myocardial SLSR of CTO territory segments was significantly lower than that of healthy controls.


Assuntos
Meios de Contraste , Gadolínio , Humanos , Coração , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Imagem Cinética por Ressonância Magnética/métodos , Valor Preditivo dos Testes
15.
Acta Radiol ; 63(5): 596-605, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33887964

RESUMO

BACKGROUND: Intravoxel incoherent motion imaging (IVIM) can non-invasively evaluate diffusion and microvascular perfusion. PURPOSE: To explore the myocardium microcirculation of a healthy Chinese population by using cardiac magnetic resonance (CMR) IVIM. MATERIAL AND METHODS: A total of 80 healthy volunteers (44 men, 36 women) who underwent 3.0-T CMR examination were enrolled. All participants had cardiac cine imaging and short-axis CMR-IVIM of the left ventricle (LV) using multiple b-values. The consistency of the IVIM parameters was assessed by intraclass correlation coefficient (ICC) and the Bland-Altman test. Spearman correlation analysis was performed between IVIM parameters and age, and body mass index (BMI). The differences of IVIM parameters were analyzed between gender and different ages. RESULTS: LV end-diastolic volume (EDV), end-systolic volume (ESV), LVmass, cardiac output (CO), and BMI in the male group were higher than those in the female group (P<0.05). IVIM parameters had good intra-observer and inter-observer consistency (≥0.75). Bland-Altman analysis also showed good intra-observer and inter-observer consistency. ADCfast decreased with increasing female age (rs = -0.37; P = 0.01), while IVIM parameters had no correlation with BMI regardless of sex. ADCfast in the female group had a statistical difference between different age groups. The ADCslow and f in the male group were lower than those in the female group (P<0.05); however, there was no statistical difference in ADCfast between genders. CONCLUSION: IVIM parameters in healthy Chinese volunteers provided good consistency. There was a negative correlation between ADCfast and age in the female group.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , China , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Masculino , Microcirculação , Movimento (Física) , Miocárdio , Reprodutibilidade dos Testes
16.
J Magn Reson Imaging ; 53(4): 1066-1079, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33217114

RESUMO

BACKGROUND: Preoperative prediction of early recurrence (ER) of hepatocellular carcinoma (HCC) plays a critical role in individualized risk stratification and further treatment guidance. PURPOSE: To investigate the role of radiomics analysis based on multiparametric MRI (mpMRI) for predicting ER in HCC after partial hepatectomy. STUDY TYPE: Retrospective. POPULATION: In all, 113 HCC patients (ER, n = 58 vs. non-ER, n = 55), divided into training (n = 78) and validation (n = 35) cohorts. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T, gradient-recalled-echo in-phase T1 -weighted imaging (I-T1 WI) and opposed-phase T1 WI (O-T1 WI), fast spin-echo T2 -weighted imaging (T2 WI), spin-echo planar diffusion-weighted imaging (DWI), and gradient-recalled-echo contrast-enhanced MRI (CE-MRI). ASSESSMENT: In all, 1146 radiomics features were extracted from each image sequence, and radiomics models based on each sequence and their combination were established via multivariate logistic regression analysis. The clinicopathologic-radiologic (CPR) model and the combined model integrating the radiomics score with the CPR risk factors were constructed. A nomogram based on the combined model was established. STATISTICAL TESTS: Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminative performance of each model. The potential clinical usefulness was evaluated by decision curve analysis (DCA). RESULTS: The radiomics model based on I-T1 WI, O-T1 WI, T2 WI, and CE-MRI sequences presented the best performance among all radiomics models with an area under the ROC curve (AUC) of 0.771 (95% confidence interval (CI): 0.598-0.894) in the validation cohort. The combined nomogram (AUC: 0.873; 95% CI: 0.756-0.989) outperformed the radiomics model and the CPR model (AUC: 0.742; 95% CI: 0.577-0.907). DCA demonstrated that the combined nomogram was clinically useful. DATA CONCLUSION: The mpMRI-based radiomics analysis has potential to predict ER of HCC patients after hepatectomy, which could enhance risk stratification and provide support for individualized treatment planning. EVIDENCE LEVEL: 4. TECHNICAL EFFICACY: Stage 4.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Imageamento por Ressonância Magnética Multiparamétrica , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética , Estudos Retrospectivos
17.
J Comput Assist Tomogr ; 45(1): 12-17, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33186174

RESUMO

METHODS: Hepatic fat fractions were quantified by noncontrast (HFFnon-CE) and contrast-enhanced single-source dual-energy computed tomography in arterial phase (HFFAP), portal venous phase (HFFPVP) and equilibrium phase (HFFEP) using MMD in 19 nonalcoholic fatty liver disease patients. The fat concentration was measured on fat (water)-based images. As the standard of reference, magnetic resonance iterative decomposition of water and fat with echo asymmetry and least-squares estimation-iron quantification images were reconstructed to obtain HFF (HFFIDEAL-IQ). RESULTS: There was a strong correlation between HFFnon-CE, HFFAP, HFFPVP, HFFEP, fat concentration and HFFIDEAL-IQ (r = 0.943, 0.923, 0.942, 0.952, and 0.726) with HFFs having better correlation with HFFIDEAL-IQ. Hepatic fat fractions did not significantly differ across scanning phases. The HFFs of 3-phase contrast-enhanced computed tomography had a good consistency with HFFnon-CE. CONCLUSIONS: Hepatic fat fraction using MMD has excellent correlation with that of magnetic resonance imaging, is independent of the computed tomography scanning phases, and may be used as a routine technique for quantitative assessment of HFF.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Tomografia Computadorizada por Raios X/métodos , Tecido Adiposo/patologia , Adulto , Idoso , Algoritmos , Meios de Contraste , Feminino , Humanos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Água
18.
Biochem Biophys Res Commun ; 533(1): 104-109, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-32933749

RESUMO

NRT1.2 has been characterized as a low-affinity nitrate transporter and an abscisic acid (ABA) transporter in Arabidopsis. In this study, we demonstrate that NRT1.2 positively regulated the ABA response during germination and seedling development. The transgenic Arabidopsis NRT1.2-over-expressionors showed increased sensitivity to ABA during these processes. qRT-PCR assays indicated that NRT1.2 over-production in 7-days-old seedlings up-regulated the expression of ABA-responsive genes: ABI1, ABI2, ABI3, ABI4, ABI5, RAB18, RD29A, and RD29B and PHOSPHOLIPASE Dα1 (PLDα1). The expression of these genes was suppressed in the nrt1.2 mutant in comparison with the wild type following ABA treatment. Importantly, bimolecular fluorescence complementation assays indicated that NRT1.2 interacts with PLDα1 at the plasma membrane. Their interaction was further confirmed by using yeast two hybrid (Y2H) experiments with the mating-based split ubiquitin system (MbSUS). Moreover, genetic assays indicated that PLDα1 acts epistatically on NRT1.2 to affect ABA signaling. Taken together, our results provide detailed mechanisms of NRT1.2 in ABA-mediated seed germination and seedling development.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Fosfolipase D/metabolismo , Proteínas de Plantas/metabolismo , Plântula/crescimento & desenvolvimento , Proteínas de Transporte de Ânions/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Germinação , Fosfolipase D/genética , Proteínas de Plantas/genética , Mapas de Interação de Proteínas , Plântula/genética , Plântula/metabolismo
19.
Med Sci Monit ; 26: e922170, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32887868

RESUMO

BACKGROUND The purpose of this research was to study and analyze the diagnostic value of magnetic resonance (MR) combined with computed tomography (CT) in patients with stress injury of the femoral neck. MATERIAL AND METHODS The 58 patients with stress injury of the femoral neck who were treated in our hospital from July 2017 until July 2019 were selected as subjects on the basis of clinical pathology and surgery, MR and CT examination, and related imaging data retrospectively analyzed. We observed all patients using different diagnostic methods to determine the value of diagnosis and treatment of disease. RESULTS The patients selected for this study were confirmed by clinicopathology and surgery; the positive rate of CT diagnosis was 65.5%, the positive rate of MR diagnosis was 74.1%, and the positive rate of combined diagnosis was 91.4%. Through statistical analysis, CT and MR showed no significant difference in the detection of stress lesions in different femoral necks, indicating no statistical significance (P>0.05). However, the amount of stress lesions detected in the combined diagnosis was higher than that in the two separate detection methods, with statistically significant difference (P<0.05). The grading of stress lesions in all patients examined through MR showed that there was no proportion of grade 0, whereas grades 3-4 were the highest, accounting for 20.7% and 32.8% respectively. In CT scanning of all patients, fracture lines were observed in 35 patients, of which 25 were transparent lines and 10 were strip dense shadows; Periosteal reaction was observed in 34 patients, of whom umbilical concave was observed in 18 patients. Osteoporosis was observed in 30 patients, and the lesion showed a zone of reduced density in the cortical bone, with a stripelike shape and unclear boundary. The density tended to increase in the cavum medullare of 32 patients, with porosis being visible. Compared with CT diagnosis, the accuracy, sensitivity, and specificity of MR detection were not significantly different (P>0.05). The accuracy, sensitivity, and specificity of the combined detection were higher than that of CT and MR detection alone, with statistically significant differences between groups (P<0.05). CONCLUSIONS The application of MR combined with CT in early clinical diagnosis and treatment of femoral neck stress injury will improve the diagnosis rate; the imaging signal is obvious, which is helpful to further evaluate the severity of disease.


Assuntos
Colo do Fêmur/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
J Cell Biochem ; 120(10): 17699-17708, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31127654

RESUMO

The long noncoding RNA HANR has been shown to be involved in the progression of hepatocellular carcinoma (HCC). However, the underlying mechanism of HCC-associated long noncoding RNA (HANR)-regulated HCC metastasis and lymphangiogenesis has not been elucidated. RT-qPCR and Western blot methods were utilized to detect the gene expressions. Interaction of HANR with miR-296 was predicted by a bioinformatic program and validated by a dual-luciferase reporter assay. For the functional experiment, a transwell invasion assay was utilized to examine the invasion abilities of HepG2 and Huh-7 cells. The lymphatic vessel formation assay was used to show the HCC-associated lymphatic vessel formation ability of human dermal lymphatic endothelial cells (HDLEC). HANR was shown to directly bind to miR-296, and miR-296 downregulated HANR expression in HepG2 cells. Then, we observed that miR-296 inhibitor transfection in shHANR HCC cells could promote lymphatic vessel formation and invasion of HDLEC cells compared with shHANR HCC cells. EAG1 or VEGFA overexpression in HDLEC cells rescued lymphatic vessel formation and invasion in HDLEC cells coincubated with the medium of HepG2 cells expressing shHANR or miR-296 mimic. Ultimately, HANR knockdown and miR-296 mimic led to a significant decrease in the EAG1 and VEGFA expression levels in HepG2 cells. Here, we reveal a novel molecular mechanism in which the HANR/miR-296/EAG1/VEGF axis is responsible for the lymphangiogenesis of HCC cells. Our findings provide more insights into developing therapeutical or diagnostic methods by targeting HANR.


Assuntos
Carcinoma Hepatocelular/genética , Células Endoteliais/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Exossomos/metabolismo , Linfangiogênese/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Sequência de Bases , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Modelos Biológicos , Invasividade Neoplásica , RNA Longo não Codificante/genética , Transdução de Sinais
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