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1.
J Magn Reson Imaging ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39036994

RESUMEN

BACKGROUND: Conventional liver magnetic resonance elastography (MRE) requires breath-holding (BH) to avoid motion artifacts, which is challenging for children. While radial free-breathing (FB)-MRE is an alternative for quantifying liver stiffness (LS), previous methods had limitations of long scan times, acquiring two slices in 5 minutes, and not resolving motion during reconstruction. PURPOSE: To reduce FB-MRE scan time to 4 minutes for four slices and to investigate the impact of self-gated (SG) motion compensation on FB-MRE LS quantification in terms of agreement, intrasession repeatability, and technical quality compared to conventional BH-MRE. STUDY TYPE: Prospective. POPULATION: Twenty-six children without fibrosis (median age: 12.9 years, 15 females). FIELD STRENGTH/SEQUENCE: 3 T; Cartesian gradient-echo (GRE) BH-MRE, research application radial GRE FB-MRE. ASSESSMENT: Participants were scanned twice to measure repeatability, without moving the table or changing the participants' position. LS was measured in areas of the liver with numerical confidence ≥90%. Technical quality was examined using measurable liver area (%). STATISTICAL TESTS: Agreement of LS between BH-MRE and FB-MRE was evaluated using Bland-Altman analysis for SG acceptance rates of 40%, 60%, 80%, and 100%. LS repeatability was assessed using within-subject coefficient of variation (wCV). The differences in LS and measurable liver area were examined using Kruskal-Wallis and Wilcoxon signed-rank tests. P < 0.05 was considered significant. RESULTS: FB-MRE with 60% SG achieved the closest agreement with BH-MRE (mean difference 0.00 kPa). The LS ranged from 1.70 to 1.83 kPa with no significant differences between BH-MRE and FB-MRE with varying SG rates (P = 0.52). All tested methods produced repeatable LS with wCV from 4.4% to 6.5%. The median measurable liver area was smaller for FB-MRE (32%-45%) than that for BH-MRE (91%-93%) (P < 0.05). DATA CONCLUSION: FB-MRE with 60% SG can quantify LS with close agreement and comparable repeatability with respect to BH-MRE in children. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 1.

2.
MAGMA ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39039272

RESUMEN

OBJECTIVE: To review the recent advancements in free-breathing MRI techniques for proton-density fat fraction (PDFF) and R2* quantification in the liver, and discuss the current challenges and future opportunities. MATERIALS AND METHODS: This work focused on recent developments of different MRI pulse sequences, motion management strategies, and reconstruction approaches that enable free-breathing liver PDFF and R2* quantification. RESULTS: Different free-breathing liver PDFF and R2* quantification techniques have been evaluated in various cohorts, including healthy volunteers and patients with liver diseases, both in adults and children. Initial results demonstrate promising performance with respect to reference measurements. These techniques have a high potential impact on providing a solution to the clinical need of accurate liver fat and iron quantification in populations with limited breath-holding capacity. DISCUSSION: As these free-breathing techniques progress toward clinical translation, studies of the linearity, bias, and repeatability of free-breathing PDFF and R2* quantification in a larger cohort are important. Scan acceleration and improved motion management also hold potential for further enhancement.

3.
Zookeys ; 1200: 65-74, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751966

RESUMEN

Lycodongammiei (Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of L.gammiei rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that L.gammiei constitutes an independent evolutionary lineage, forming a clade with L.fasciatus (Anderson, 1879), L.gongshan Vogel & Luo, 2011, L.butleri Boulenger, 1900, and L.cavernicolus Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between L.gammiei and its congeners was 10.2%. The discovery of L.gammiei in Medog County, China, signifies an eastward expansion of its known geographical distribution.

4.
Magn Reson Med ; 92(3): 1149-1161, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38650444

RESUMEN

PURPOSE: To improve image quality, mitigate quantification biases and variations for free-breathing liver proton density fat fraction (PDFF) and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ quantification accelerated by radial k-space undersampling. METHODS: A free-breathing multi-echo stack-of-radial MRI method was developed with compressed sensing with multidimensional regularization. It was validated in motion phantoms with reference acquisitions without motion and in 11 subjects (6 patients with nonalcoholic fatty liver disease) with reference breath-hold Cartesian acquisitions. Images, PDFF, and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ maps were reconstructed using different radial view k-space sampling factors and reconstruction settings. Results were compared with reference-standard results using Bland-Altman analysis. Using linear mixed-effects model fitting (p < 0.05 considered significant), mean and SD were evaluated for biases and variations of PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ , respectively, and coefficient of variation on the first echo image was evaluated as a surrogate for image quality. RESULTS: Using the empirically determined optimal sampling factor of 0.25 in the accelerated in vivo protocols, mean differences and limits of agreement for the proposed method were [-0.5; -33.6, 32.7] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-1.0%; -5.8%, 3.8%] for PDFF, close to those of a previous self-gating method using fully sampled radial views: [-0.1; -27.1, 27.0] s-1 for R 2 * $$ {\mathrm{R}}_2^{\ast } $$ and [-0.4%; -4.5%, 3.7%] for PDFF. The proposed method had significantly lower coefficient of variation than other methods (p < 0.001). Effective acquisition time of 64 s or 59 s was achieved, compared with 171 s or 153 s for two baseline protocols with different radial views corresponding to sampling factor of 1.0. CONCLUSION: This proposed method may allow accelerated free-breathing liver PDFF and R 2 * $$ {\mathrm{R}}_2^{\ast } $$ mapping with reduced biases and variations.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Hígado , Imagen por Resonancia Magnética , Fantasmas de Imagen , Humanos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Femenino , Masculino , Procesamiento de Imagen Asistido por Computador/métodos , Persona de Mediana Edad , Respiración , Algoritmos , Adulto , Reproducibilidad de los Resultados , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Movimiento (Física) , Tejido Adiposo/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Anciano
5.
Heliyon ; 10(7): e29055, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38576565

RESUMEN

Background: Anaplastic thyroid cancer (ATC), a rare and aggressive malignancy with a poor prognosis, has shown promise with the approved dabrafenib/trametinib combination for BRAFV600E mutation. Co-occurring PI3KCA mutations, identified as negative prognostic factors in lung cancer with BRAFV600E mutation, emphasize the need to target both pathways. Exploring trametinib and alpelisib combination becomes crucial for ATC. Methods: A patient-derived xenograft (PDX) and primary cell line were obtained from an ATC patient with BRAF and PI3KCA co-mutation. Individual testing of targeted therapies against BRAF, MEK, and PI3KCA was followed by a combination treatment. Synergistic effects were evaluated using the combination index. Immunoblotting assessed the efficacy, with validation performed using a PDX model. Results: In this study, the ATC0802 cell line and PDX were established from a refractory ATC patient. NGS revealed BRAF and PI3KCA co-mutations pre- and post-dabrafenib/trametinib treatment. Trametinib/alpelisib combination showed synergy, suppressing both pERK and pAKT levels, unlike monotherapies or BRAF knockdown. The combination induced apoptosis and, in the PDX model, demonstrated superior tumor growth inhibition compared to monotherapies. Conclusions: The combination of trametinib and alpelisib showed promise as a strategy for treating ATC with co-mutations in BRAF and PI3KCA, both in vitro and in vivo. This combination offers insights into overcoming resistance to BRAF-targeted treatments in ATC with mutations in BRAF and PI3KCA.

6.
MAGMA ; 37(3): 491-506, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38300360

RESUMEN

OBJECTIVE: Increased subcutaneous and visceral adipose tissue (SAT/VAT) volume is associated with risk for cardiometabolic diseases. This work aimed to develop and evaluate automated abdominal SAT/VAT segmentation on longitudinal MRI in adults with overweight/obesity using attention-based competitive dense (ACD) 3D U-Net and 3D nnU-Net with full field-of-view volumetric multi-contrast inputs. MATERIALS AND METHODS: 920 adults with overweight/obesity were scanned twice at multiple 3 T MRI scanners and institutions. The first scan was divided into training/validation/testing sets (n = 646/92/182). The second scan from the subjects in the testing set was used to evaluate the generalizability for longitudinal analysis. Segmentation performance was assessed by measuring Dice scores (DICE-SAT, DICE-VAT), false negatives (FN), and false positives (FP). Volume agreement was assessed using the intraclass correlation coefficient (ICC). RESULTS: ACD 3D U-Net achieved rapid (< 4.8 s/subject) segmentation with high DICE-SAT (median ≥ 0.994) and DICE-VAT (median ≥ 0.976), small FN (median ≤ 0.7%), and FP (median ≤ 1.1%). 3D nnU-Net yielded rapid (< 2.5 s/subject) segmentation with similar DICE-SAT (median ≥ 0.992), DICE-VAT (median ≥ 0.979), FN (median ≤ 1.1%) and FP (median ≤ 1.2%). Both models yielded excellent agreement in SAT/VAT volume versus reference measurements (ICC > 0.997) in longitudinal analysis. DISCUSSION: ACD 3D U-Net and 3D nnU-Net can be automated tools to quantify abdominal SAT/VAT volume rapidly, accurately, and longitudinally in adults with overweight/obesity.


Asunto(s)
Grasa Abdominal , Imagenología Tridimensional , Grasa Intraabdominal , Imagen por Resonancia Magnética , Redes Neurales de la Computación , Obesidad , Humanos , Imagen por Resonancia Magnética/métodos , Femenino , Masculino , Persona de Mediana Edad , Adulto , Imagenología Tridimensional/métodos , Grasa Abdominal/diagnóstico por imagen , Obesidad/diagnóstico por imagen , Grasa Intraabdominal/diagnóstico por imagen , Estudios Longitudinales , Sobrepeso/diagnóstico por imagen , Reproducibilidad de los Resultados , Anciano , Medios de Contraste , Algoritmos , Interpretación de Imagen Asistida por Computador/métodos
7.
MAGMA ; 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349453

RESUMEN

OBJECTIVE: To develop and evaluate a technique combining eddy current-nulled convex optimized diffusion encoding (ENCODE) with random matrix theory (RMT)-based denoising to accelerate and improve the apparent signal-to-noise ratio (aSNR) and apparent diffusion coefficient (ADC) mapping in high-resolution prostate diffusion-weighted MRI (DWI). MATERIALS AND METHODS: Eleven subjects with clinical suspicion of prostate cancer were scanned at 3T with high-resolution (HR) (in-plane: 1.0 × 1.0 mm2) ENCODE and standard-resolution (1.6 × 2.2 mm2) bipolar DWI sequences (both had 7 repetitions for averaging, acquisition time [TA] of 5 min 50 s). HR-ENCODE was retrospectively analyzed using three repetitions (accelerated effective TA of 2 min 30 s). The RMT-based denoising pipeline utilized complex DWI signals and Marchenko-Pastur distribution-based principal component analysis to remove additive Gaussian noise in images from multiple coils, b-values, diffusion encoding directions, and repetitions. HR-ENCODE with RMT-based denoising (HR-ENCODE-RMT) was compared with HR-ENCODE in terms of aSNR in prostate peripheral zone (PZ) and transition zone (TZ). Precision and accuracy of ADC were evaluated by the coefficient of variation (CoV) between repeated measurements and mean difference (MD) compared to the bipolar ADC reference, respectively. Differences were compared using two-sided Wilcoxon signed-rank tests (P < 0.05 considered significant). RESULTS: HR-ENCODE-RMT yielded 62% and 56% higher median aSNR than HR-ENCODE (b = 800 s/mm2) in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT achieved 63% and 70% lower ADC-CoV than HR-ENCODE in PZ and TZ, respectively (P < 0.001). HR-ENCODE-RMT ADC and bipolar ADC had low MD of 22.7 × 10-6 mm2/s in PZ and low MD of 90.5 × 10-6 mm2/s in TZ. CONCLUSIONS: HR-ENCODE-RMT can shorten the acquisition time and improve the aSNR of high-resolution prostate DWI and achieve accurate and precise ADC measurements in the prostate.

8.
Zhongguo Zhong Yao Za Zhi ; 49(2): 361-369, 2024 Jan.
Artículo en Chino | MEDLINE | ID: mdl-38403312

RESUMEN

The 4-coumarate: CoA ligase(4CL) is a key enzyme in the upstream pathway of phenylpropanoids such as flavonoids, soluble phenolic esters, lignans, and lignins in plants. In this study, 13 4CL family members of Arabidopsis thaliana were used as reference sequences to identify the 4CL gene family candidate members of Isatis indigotica from the reported I. indigotica genome. Further bioinformatics analysis and analysis of the expression pattern of 4CL genes and the accumulation pattern of flavonoids were carried out. Thirteen 4CL genes were obtained, named Ii4CL1-Ii4CL13, which were distributed on chromosomes 1, 2, 3, 4, and 6. The analysis of the gene structure and conserved structural domains revealed the intron number of I. indigotica 4CL genes was between 1 and 12 and the protein structural domains were highly conserved. Cis-acting element analysis showed that there were multiple response elements in the promoter sequence of I. indigotica 4CL gene family, and jasmonic acid had the largest number of reaction elements. The collinearity analysis showed that there was a close relationship between the 4CL gene family members of I. indigotica and A. thaliana. As revealed by qPCR results, the expression analysis of the 4CL gene family showed that 10 4CL genes had higher expression levels in the aboveground part of I. indigotica. The content assay of flavonoids in different parts of I. indigotica showed that flavonoids were mainly accumulated in the aboveground part of plants. This study provides a basis for further investigating the roles of the 4CL gene family involved in the biosynthesis of flavonoids in I. indigotica.


Asunto(s)
Isatis , Ligasas , Ligasas/genética , Isatis/genética , Regiones Promotoras Genéticas , Plantas/metabolismo , Flavonoides , Coenzima A Ligasas/genética , Coenzima A Ligasas/química , Coenzima A Ligasas/metabolismo
9.
Am J Occup Ther ; 78(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38215306

RESUMEN

IMPORTANCE: Establishing empirical evidence on the psychometric properties of the Test of Visual-Motor Skills (3rd ed.; TVMS-3) is helpful for guiding its use as an assessment of visual-motor integration (VMI) skills in kindergarten children with developmental coordination disorder (DCD). OBJECTIVE: To investigate the test-retest reliability, criterion-related validity, and ecological validity of the TVMS-3 in Taiwanese kindergarten children with DCD. DESIGN: A nonexperimental, descriptive, correlational design. SETTING: A hospital in Central Taiwan. PARTICIPANTS: Fifty-seven kindergarten children with DCD were recruited in the study. OUTCOMES AND MEASURES: Intraclass correlation coefficient, percentage of minimal detectable change, and paired t test (Wilcoxon signed rank test) were used to investigate the test-retest reliability of the TVMS-3. The correlations (Pearson's r) between the TVMS-3 accuracy score and the scores of each of the four domains and the adaptive behavior composite score of the Vineland Adaptive Behavior Scales (3rd ed.; Vineland-3) were calculated, respectively, to examine criterion-related validity and ecological validity. RESULTS: The accuracy score of the TVMS-3 had excellent test-retest reliability and acceptable random measurement error. Moreover, it showed good criterion-related validity and sufficient ecological validity with the Vineland-3 in Taiwanese kindergarten children with DCD. CONCLUSIONS AND RELEVANCE: The accuracy score of the TVMS-3 is applicable to Taiwanese kindergarten children with DCD in clinical and research settings. Plain-Language Summary: The accuracy score of the Test of Visual-Motor Skills (3rd ed.; TVMS-3) is a useful assessment tool to detect deficits in visual-motor integration for Taiwanese kindergarten children with developmental coordination disorder. The TVMS-3 has excellent test-retest reliability, good criterion-related validity, and sufficient ecological validity.


Asunto(s)
Trastornos de la Destreza Motora , Destreza Motora , Niño , Humanos , Trastornos de la Destreza Motora/diagnóstico , Reproducibilidad de los Resultados , Escolaridad , Instituciones Académicas , Psicometría
10.
CNS Neurosci Ther ; 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082503

RESUMEN

Neurodegenerative diseases (NDs) constitute a group of disorders characterized by the progressive deterioration of nervous system functionality. Currently, the precise etiological factors responsible for NDs remain incompletely elucidated, although it is probable that a combination of aging, genetic predisposition, and environmental stressors participate in this process. Accumulating evidence indicates that viral infections, especially neurotropic viruses, can contribute to the onset and progression of NDs. In this review, emerging evidence supporting the association between viral infection and NDs is summarized, and how the autophagy pathway mediated by viral infection can cause pathological aggregation of cellular proteins associated with various NDs is discussed. Furthermore, autophagy-related genes (ARGs) involved in Herpes simplex virus (HSV-1) infection and NDs are analyzed, and whether these genes could link HSV-1 infection to NDs is discussed. Elucidating the mechanisms underlying NDs is critical for developing targeted therapeutic approaches that prevent the onset and slow the progression of NDs.

11.
Endocr Relat Cancer ; 30(12)2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37902083

RESUMEN

Ataxia telangiectasia and Rad3-related protein (ATR) is a critical component of the DNA damage response and a potential target in the treatment of cancers. An ATR inhibitor, BAY 1895344, was evaluated for its use in differentiated thyroid cancer (DTC) therapy. BAY 1895344 inhibited cell viability in four DTC cell lines (TPC1, K1, FTC-133, and FTC-238) in a dose-dependent manner. BAY 1895344 treatment arrested DTC cells in the G2/M phase, increased caspase-3 activity, and caused apoptosis. BAY 1895344 in combination with either sorafenib or lenvatinib showed mainly synergistic effects in four DTC cell lines. The combination of BAY 1895344 with dabrafenib plus trametinib revealed synergistic effects in K1 cells that harbor BRAFV600E. BAY 1895344 monotherapy retarded the growth of K1 and FTC-133 tumors in xenograft models. The combinations of BAY 1895344 plus lenvatinib and BAY 1895344 with dabrafenib plus trametinib were more effective than any single therapy in a K1 xenograft model. No appreciable toxicity appeared in animals treated with either a single therapy or a combination treatment. Our findings provide the rationale for the development of clinical trials of BAY 1895344 in the treatment of DTC.


Asunto(s)
Adenocarcinoma , Neoplasias de la Tiroides , Animales , Humanos , Neoplasias de la Tiroides/patología , Compuestos de Fenilurea/farmacología , Compuestos de Fenilurea/uso terapéutico , Sorafenib/farmacología , Adenocarcinoma/tratamiento farmacológico , Proteínas de la Ataxia Telangiectasia Mutada
12.
Otolaryngol Head Neck Surg ; 169(6): 1424-1435, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37548067

RESUMEN

OBJECTIVES: To evaluate the efficacy and safety of macrolide antibiotics therapy in patients with chronic rhinosinusitis (CRS) receiving endoscopic sinus surgery. DATA SOURCES: PubMed, Web of Science, Embase, and Cochrane Library. REVIEW METHODS: The electronic databases were comprehensively searched on June 2, 2022, for randomized controlled trials on macrolide antibiotics in the treatment of patients undergoing CRS endoscopic surgery. The primary outcome measures were the sinonasal outcome test (SNOT) score and the visual analog scale (VAS) score. The secondary outcome measures were the nasal endoscopy score (NES), the sinus computed tomography score, and adverse events. RESULTS: A total of 8 studies were included, involving 606 patients who used macrolide for a long time. Meta-analysis showed that no significant difference was observed in SNOT (standardized mean difference [SMD] = -0.13; 95% confidence interval [CI]: -0.38 to 0.13, I2 = 0%) and VAS (SMD = -0.10; 95% CI, -0.88 to 0.68, I2 = 81%) between the macrolide and placebo groups. However, macrolide outperformed the placebo in improving NES (SMD = -0.32; 95% CI, -0.62 to -0.03, I2 = 21%). The use of macrolide did not increase the incidence of adverse events. CONCLUSION: Long-term use of macrolide after CRS surgery may not significantly improve the quality of life and disease severity of the patients but may play a role in improving postoperative NES in patients with CRS. There is still no sufficient evidence to determine whether the disease phenotype of CRS or the patient's race will affect the efficacy of long-term use of macrolide after CRS.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Macrólidos/uso terapéutico , Calidad de Vida , Rinitis/tratamiento farmacológico , Rinitis/cirugía , Pólipos Nasales/cirugía , Sinusitis/tratamiento farmacológico , Sinusitis/cirugía , Antibacterianos/uso terapéutico , Enfermedad Crónica , Endoscopía/métodos
13.
Zhongguo Zhong Yao Za Zhi ; 48(6): 1510-1517, 2023 Mar.
Artículo en Chino | MEDLINE | ID: mdl-37005838

RESUMEN

Chalcone isomerase is a key rate-limiting enzyme in the biosynthesis of flavonoids in higher plants, which determines the production of flavonoids in plants. In this study, RNA was extracted from different parts of Isatis indigotica and reverse-transcribed into cDNA. Specific primers with enzyme restriction sites were designed, and a chalcone isomerase gene was cloned from I. indigotica, named IiCHI. IiCHI was 756 bp in length, containing a complete open reading frame and encoding 251 amino acids. Homology analysis showed that IiCHI was closely related to CHI protein of Arabidopsis thaliana and had typical active sites of chalcone isomerase. Phylogenetic tree analysis showed that IiCHI was classified into type Ⅰ CHI clade. Recombinant prokaryotic expression vector pET28a-IiCHI was constructed and purified to obtain IiCHI recombinant protein. In vitro enzymatic analysis showed that the IiCHI protein could convert naringenin chalcone into naringenin, but could not catalyze the production of liquiritigenin by isoliquiritigenin. The results of real-time quantitative polymerase chain reaction(qPCR) showed that the expression level of IiCHI in the aboveground parts was higher than that in the underground parts and the expression level was the highest in the flowers of the aboveground parts, followed by leaves and stems, and no expression was observed in the roots and rhizomes of the underground parts. This study has confirmed the function of chalcone isomerase in I. indigotica and provided references for the biosynthesis of flavonoid components.


Asunto(s)
Arabidopsis , Isatis , Isatis/genética , Proteínas de Plantas/metabolismo , Filogenia , Arabidopsis/genética , Flavonoides , Clonación Molecular
14.
Magn Reson Med ; 89(4): 1567-1585, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36426730

RESUMEN

PURPOSE: To develop a deep learning-based method for rapid liver proton-density fat fraction (PDFF) and R2 * quantification with built-in uncertainty estimation using self-gated free-breathing stack-of-radial MRI. METHODS: This work developed an uncertainty-aware physics-driven deep learning network (UP-Net) to (1) suppress radial streaking artifacts because of undersampling after self-gating, (2) calculate accurate quantitative maps, and (3) provide pixel-wise uncertainty maps. UP-Net incorporated a phase augmentation strategy, generative adversarial network architecture, and an MRI physics loss term based on a fat-water and R2 * signal model. UP-Net was trained and tested using free-breathing multi-echo stack-of-radial MRI data from 105 subjects. UP-Net uncertainty scores were calibrated in a validation dataset and used to predict quantification errors for liver PDFF and R2 * in a testing dataset. RESULTS: Compared with images reconstructed using compressed sensing (CS), UP-Net achieved structural similarity index >0.87 and normalized root mean squared error <0.18. Compared with reference quantitative maps generated using CS and graph-cut (GC) algorithms, UP-Net achieved low mean differences (MD) for liver PDFF (-0.36%) and R2 * (-0.37 s-1 ). Compared with breath-holding Cartesian MRI results, UP-Net achieved low MD for liver PDFF (0.53%) and R2 * (6.75 s-1 ). UP-Net uncertainty scores predicted absolute liver PDFF and R2 * errors with low MD of 0.27% and 0.12 s-1 compared to CS + GC results. The computational time for UP-Net was 79 ms/slice, whereas CS + GC required 3.2 min/slice. CONCLUSION: UP-Net rapidly calculates accurate liver PDFF and R2 * maps from self-gated free-breathing stack-of-radial MRI. The pixel-wise uncertainty maps from UP-Net predict quantification errors in the liver.


Asunto(s)
Aprendizaje Profundo , Humanos , Incertidumbre , Interpretación de Imagen Asistida por Computador/métodos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Protones
15.
J Magn Reson Imaging ; 57(2): 508-518, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35778376

RESUMEN

BACKGROUND: MRI acquisition for pediatric pancreatic fat quantification is limited by breath-holds (BH). Full segmentation (FS) or small region of interest (ROI) analysis methods may not account for pancreatic fat spatial heterogeneity, which may limit accuracy. PURPOSE: To improve MRI acquisition and analysis for quantifying pancreatic proton-density fat fraction (pPDFF) in children by investigating free-breathing (FB)-MRI, characterizing pPDFF spatial heterogeneity, and relating pPDFF to clinical markers. STUDY TYPE: Prospective. POPULATION: A total of 34 children, including healthy (N = 16, 8 female) and overweight (N = 18, 5 female) subjects. FIELD STRENGTH AND SEQUENCES: 3 T; multiecho gradient-echo three-dimensional (3D) stack-of-stars FB-MRI, multiecho gradient-echo 3D Cartesian BH-MRI. ASSESSMENT: A radiologist measured FS- and ROI-based pPDFF on FB-MRI and BH-MRI PDFF maps, with anatomical images as references. Regional pPDFF in the pancreatic head, body, and tail were measured on FB-MRI. FS-pPDFF, ROI-pPDFF, and regional pPDFF were compared, and related to clinical markers, including hemoglobin A1c. STATISTICAL TESTS: T-test, Bland-Altman analysis, Lin's concordance correlation coefficient (CCC), one-way analysis of variance, and Spearman's rank correlation coefficient were used. P < 0.05 was considered significant. RESULTS: FS-pPDFF and ROI-pPDFF from FB-MRI and BH-MRI had mean difference = 0.4%; CCC was 0.95 for FS-pPDFF and 0.62 for ROI-pPDFF. FS-pPDFF was higher than ROI-pPDFF (10.4% ± 6.4% vs. 4.2% ± 2.8%). Tail-pPDFF (11.6% ± 8.1%) was higher than body-pPDFF (8.9% ± 6.3%) and head-pPDFF (8.7% ± 5.2%). Head-pPDFF and body-pPDFF positively correlated with hemoglobin A1c. DATA CONCLUSION: FB-MRI pPDFF is comparable to BH-MRI. Spatial heterogeneity affects pPDFF quantification. Regional measurements of pPDFF in the head and body were correlated with hemoglobin A1c, a marker of insulin sensitivity. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Humanos , Niño , Femenino , Estudios Prospectivos , Hemoglobina Glucada , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Protones , Biomarcadores , Hígado
16.
Magn Reson Imaging ; 95: 70-79, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36270417

RESUMEN

PURPOSE: Stack-of-radial MRI allows free-breathing abdominal scans, however, it requires relatively long acquisition time. Undersampling reduces scan time but can cause streaking artifacts and degrade image quality. This study developed deep learning networks with adversarial loss and evaluated the performance of reducing streaking artifacts and preserving perceptual image sharpness. METHODS: A 3D generative adversarial network (GAN) was developed for reducing streaking artifacts in stack-of-radial abdominal scans. Training and validation datasets were self-gated to 5 respiratory states to reduce motion artifacts and to effectively augment the data. The network used a combination of three loss functions to constrain the anatomy and preserve image quality: adversarial loss, mean-squared-error loss and structural similarity index loss. The performance of the network was investigated for 3-5 times undersampled data from 2 institutions. The performance of the GAN for 5 times accelerated images was compared with a 3D U-Net and evaluated using quantitative NMSE, SSIM and region of interest (ROI) measurements as well as qualitative scores of radiologists. RESULTS: The 3D GAN showed similar NMSE (0.0657 vs. 0.0559, p = 0.5217) and significantly higher SSIM (0.841 vs. 0.798, p < 0.0001) compared to U-Net. ROI analysis showed GAN removed streaks in both the background air and the tissue and was not significantly different from the reference mean and variations. Radiologists' scores showed GAN had a significant improvement of 1.6 point (p = 0.004) on a 4-point scale in streaking score while no significant difference in sharpness score compared to the input. CONCLUSION: 3D GAN removes streaking artifacts and preserves perceptual image details.


Asunto(s)
Artefactos , Imagen por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Respiración , Movimiento (Física) , Procesamiento de Imagen Asistido por Computador/métodos
17.
J Perinatol ; 43(1): 44-51, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36319757

RESUMEN

INTRODUCTION: Maternal body composition may influence fetal body composition. OBJECTIVE: The objective of this pilot study was to investigate the relationship between maternal and fetal body composition. METHODS: Three pregnant women cohorts were studied: healthy, gestational diabetes (GDM), and fetal growth restriction (FGR). Maternal body composition (visceral adipose tissue volume (VAT), subcutaneous adipose tissue volume (SAT), pancreatic and hepatic proton-density fat fraction (PDFF) and fetal body composition (abdominal SAT and hepatic PDFF) were measured using MRI between 30 to 36 weeks gestation. RESULTS: Compared to healthy and FGR fetuses, GDM fetuses had greater hepatic PDFF (5.2 [4.2, 5.5]% vs. 3.2 [3, 3.3]% vs. 1.9 [1.4, 3.7]%, p = 0.004). Fetal hepatic PDFF was associated with maternal SAT (r = 0.47, p = 0.02), VAT (r = 0.62, p = 0.002), and pancreatic PDFF (r = 0.54, p = 0.008). When controlling for maternal SAT, GDM increased fetal hepatic PDFF by 0.9 ([0.51, 1.3], p = 0.001). CONCLUSION: In this study, maternal SAT, VAT, and GDM status were positively associated with fetal hepatic PDFF.


Asunto(s)
Diabetes Gestacional , Humanos , Femenino , Embarazo , Retardo del Crecimiento Fetal/diagnóstico por imagen , Retardo del Crecimiento Fetal/patología , Proyectos Piloto , Composición Corporal , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Imagen por Resonancia Magnética/métodos , Feto/diagnóstico por imagen
18.
Zookeys ; 1166: 315-331, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38328667

RESUMEN

A new species, Achalinushunanensissp. nov., is described from middle and western Hunan Province based on the results of molecular systematics and morphological characters. It diverges from known congeners by a significant genetic divergence (p-distance 3.2%-16.9% based on CO1 mitochondrial gene), and it can be distinguished from all known congeners by the following morphological characters: (1) all dorsal scales strongly keeled, 23 rows throughout the body, the outmost one strongly keeled and enlarged; (2) tail relatively short, TaL/TL 0.221 ~ 0.225; (3) maxillary teeth 23; (4) the suture between internasals 2 × as long as that between prefrontals; (5) loreal one, subrectangular, LorH/LorL 0.62 ~ 0.70; (6) supralabials 6, the 4th and 5th touch the eye; (7) the two anterior temporals in contact with eye; (8) ventrals 163-165, subcaudals 69-72, not paired. This raises the number of known species of Achalinus to 24.

19.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6442-6456, 2023 Dec.
Artículo en Chino | MEDLINE | ID: mdl-38212002

RESUMEN

The present study aimed to investigate the effect of Xianglian Pills(XLP) on lipid metabolism in obese mice and explore the underlying mechanism based on network pharmacology and intestinal flora. Firstly, network pharmacology was used to predict the possible effect of XLP on obesity. Secondly, an obese mouse model induced by a high-fat diet was established to observe changes in mouse body weight, adiposity index, liver and adipose tissue pathology. Lipid profiles, liver and kidney function markers, insulin content, and the expression of recombinant uncoupling protein 1(UCP-1) and PR structural domain protein 16(PRDM16) were measured. The 16S rRNA gene sequencing technology was used to analyze the changes in the intestinal flora. Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis showed that XLP mainly played a role in improving obesity by regulating lipolysis, type 2 diabetes mellitus, and insulin resistance. The results of animal experiments showed that XLP significantly reduced body weight, adiposity, blood lipid levels, and serum insulin levels in obese mice, while enhancing the expression of UCP-1 and PRDM16 in adipose tissue without causing damage to the liver or kidneys. The 16S rRNA gene sequencing results showed that XLP decreased the Firmicutes/Bacteroidetes(F/B) ratio at the phylum level, increased the relative abundance of Akkermansia and Bacteroides at the family and genus levels, and reduced the abundance of Allobaculum. Therefore, XLP can effectively improve lipid metabolism disorders in high-fat diet-induced obese mice, and the mechanism is related to the improvement of brown adipose function, the browning of white fat, the accelerated lipid metabolism, and the improvement of intestinal flora. However, its effect on promoting the conversion of white adipose to brown adipose still needs to be further studied.


Asunto(s)
Diabetes Mellitus Tipo 2 , Medicamentos Herbarios Chinos , Dislipidemias , Microbioma Gastrointestinal , Ratones , Animales , Ratones Obesos , Dieta Alta en Grasa/efectos adversos , Farmacología en Red , ARN Ribosómico 16S , Diabetes Mellitus Tipo 2/complicaciones , Obesidad/tratamiento farmacológico , Obesidad/genética , Peso Corporal , Lípidos , Insulina , Factores de Transcripción , Dislipidemias/tratamiento farmacológico , Dislipidemias/genética , Ratones Endogámicos C57BL
20.
Zhongguo Zhong Yao Za Zhi ; 47(15): 4074-4083, 2022 Aug.
Artículo en Chino | MEDLINE | ID: mdl-36046897

RESUMEN

The lignan glycosyltransferase UGT236(belonging to the UGT71 B family) from Isatis indigotica can catalyze the production of phloridzin from phloretin in vitro. UGT236 shares high identity with P2'GT from apple. In this study, the recombinant plasmid pET28 a-MBP-UGT236 was transferred into Escherichia coli Rosetta(DE3) cells and induced by isopropyl-ß-D-thiogalactoside(IPTG). The purified UGT236 protein was used for enzymatic characterization with phloretin as substrate. The results showed that UGT236 had the optimal reaction temperature of 40 ℃ and the optimal pH 8(Na_2HPO_4-NaH_2PO_4 system). The UGT236 activity was inhibited by Ni~(2+) and Al~(3+), enhanced by Fe~(2+), Co~(2+), and Mn~(2+), and did not affected by Mg~(2+), Ca~(2+), Li~+, Na~+, or K~+. The K_m, K_(cat), and K_(cat)/K_m of phloretin were 61.03 µmol·L~(-1), 0.01 s~(-1), and 157.11 mol~(-1)·s~(-1)·L, and those of UDPG were 183.6 µmol·L~(-1), 0.01 s~(-1), and 51.91 mol~(-1)·s~(-1)·L, respectively. The possible active sites were predicted by homologous modeling and molecular docking. By mutagenisis and catalytic activity detection, three key active sites, Glu391, His15, and Thr141, were identified, while Phe146 was related to product diversity. In summary, we found that the lignan glycosyltransferase UGT236 from I.indigotica could catalyze the reaction of phloretin into phloridzin. Several key amino acid residues were identified by structure prediction, molecular docking, and site-mutagenesis, which provided a basis for studying the specificity and diversity of phloretin glycoside products. This study can provide a reference for artificially producing glycosyltransferase elements with high efficiency and specific catalysis.


Asunto(s)
Isatis , Lignanos , Glucosiltransferasas/genética , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Lignanos/metabolismo , Simulación del Acoplamiento Molecular , Floretina/metabolismo , Florizina/metabolismo
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