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1.
BMC Plant Biol ; 24(1): 114, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38365570

RESUMEN

BACKGROUND: The small YABBY plant-specific transcription factor has a prominent role in regulating plant growth progress and responding to abiotic stress. RESULTS: Here, a total of 16 PvYABBYs from switchgrass (Panicum virgatum L.) were identified and classified into four distinct subgroups. Proteins within the same subgroup exhibited similar conserved motifs and gene structures. Synteny analyses indicated that segmental duplication contributed to the expansion of the YABBY gene family in switchgrass and that complex duplication events occurred in rice, maize, soybean, and sorghum. Promoter regions of PvYABBY genes contained numerous cis-elements related to stress responsiveness and plant hormones. Expression profile analysis indicated higher expression levels of many PvYABBY genes during inflorescence development and seed maturation, with lower expression levels during root growth. Real-time quantitative PCR analysis demonstrated the sensitivity of multiple YABBY genes to PEG, NaCl, ABA, and GA treatments. The overexpression of PvYABBY14 in Arabidopsis resulted in increased root length after treatment with GA and ABA compared to wild-type plants. CONCLUSIONS: Taken together, our study provides the first genome-wide overview of the YABBY transcription factor family, laying the groundwork for understanding the molecular basis and regulatory mechanisms of PvYABBY14 in response to ABA and GA responses in switchgrass.


Asunto(s)
Arabidopsis , Panicum , Panicum/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Reguladores del Crecimiento de las Plantas , Genes de Plantas , Estrés Fisiológico/genética , Factores de Transcripción/genética , Regulación de la Expresión Génica de las Plantas , Filogenia , Proteínas de Plantas/metabolismo
2.
Langmuir ; 40(6): 3248-3259, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38298055

RESUMEN

Coalescence-induced jumping has promised a substantial reduction in the droplet detachment size and consequently shows great potential for heat-transfer enhancement in dropwise condensation. In this work, using molecular dynamics simulations, the evolution dynamics of the liquid bridge and the jumping velocity during coalescence-induced nanodroplet jumping under a perpendicular electric field are studied for the first time to further promote jumping. It is found that using a constant electric field, the jumping performance at the small intensity is weakened owing to the continuously decreased interfacial tension. There is a critical intensity above which the electric field can considerably enhance the stretching effect with a stronger liquid-bridge impact and, hence, improve the jumping performance. For canceling the inhibition effect of the interfacial tension under the condition of the weak electric field, a square-pulsed electric field with a paused electrical effect at the expansion stage of the liquid bridge is proposed and presents an efficient nanodroplet jumping even using the weak electric field.

3.
J Xray Sci Technol ; 32(2): 229-252, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38306088

RESUMEN

Compared with conventional single-energy computed tomography (CT), dual-energy CT (DECT) provides better material differentiation but most DECT imaging systems require dual full-angle projection data at different X-ray spectra. Relaxing the requirement of data acquisition is an attractive research to promote the applications of DECT in wide range areas and reduce the radiation dose as low as reasonably achievable. In this work, we design a novel DECT imaging scheme with dual quarter scans and propose an efficient method to reconstruct the desired DECT images from the dual limited-angle projection data. We first study the characteristics of limited-angle artifacts under dual quarter scans scheme, and find that the negative and positive artifacts of DECT images are complementarily distributed in image domain because the corresponding X-rays of high- and low-energy scans are symmetric. Inspired by this finding, a fusion CT image is generated by integrating the limited-angle DECT images of dual quarter scans. This strategy enhances the true image information and suppresses the limited-angle artifacts, thereby restoring the image edges and inner structures. Utilizing the capability of neural network in the modeling of nonlinear problem, a novel Anchor network with single-entry double-out architecture is designed in this work to yield the desired DECT images from the generated fusion CT image. Experimental results on the simulated and real data verify the effectiveness of the proposed method. This work enables DECT on imaging configurations with half-scan and largely reduces scanning angles and radiation doses.


Asunto(s)
Algoritmos , Tomografía Computarizada por Rayos X , Fantasmas de Imagen , Tomografía Computarizada por Rayos X/métodos , Redes Neurales de la Computación , Cintigrafía
4.
Langmuir ; 39(2): 829-840, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36594668

RESUMEN

Random vapor nucleation leads to flooding condensation with degraded heat-transfer efficiency. Since an external electric field has a significant effect on manipulating droplets' motion, it is possible to be one of the effective methods to hinder flooding phenomena and improve the heat-transfer rate by applying the external electric field during condensation. However, the motion of nanodroplets is more sensitive to the electric field owing to the scale effect on the nanoscale. The effect of the electric field on growth has not explicitly been comprehended. This work studied the condensation processes on a nanodimpled surface under an electric field with various strengths and directions. The results showed that condensed droplets' growth under the electric field depends on the competition between the electric field force and solid-liquid interactions. Increased vertical electric field strength, the higher torsion by the electric field hindered the motion of vapor, decreased the collision frequency for water molecules with the cooled surface, and elongated the cluster when the electric field force dominates, thus deteriorating the condensation performance. While applying the horizontal electric field, the greater electric field strength leads to better condensation performance by the larger contacting area for heat exchange. A wetting transition induced by the electric field was observed when the electric field strength increased to a certain extent (E > 5.2 × 108 V/m in this study). When the V-shaped surface replaced the dimpled surface as the condensed substrate, the same wetting transition phenomena occurred under a more significant horizontal electric field strength, showing that this method is universal. Besides, different electric field frequencies influenced both the growth and the nucleation, thus exhibiting various condensation performances.

5.
Langmuir ; 39(49): 18052-18059, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38010376

RESUMEN

We investigated the microscale electrohydrodynamic (EHD) conduction pumps in a wide range of working regimes, from the saturation regime to the ohmic regime. We showed that the existing macro- and microscale theoretical models could not accurately predict the electric force of microscale EHD conduction pumps, especially for the cases of a strong diffusion effect. We clarified that the failure is caused by a rough estimate of the heterocharge layer thickness. We revised the expression of heterocharge layer thickness by considering the diffusion effect and developed a new theoretical model for the microscale EHD conduction pumps based on the revised expression of heterocharge layer thickness. The results showed that our model can accurately predict the dimensionless electric force of the microscale EHD conduction pumps even for the cases of a strong diffusion effect. Furthermore, we developed a working regime map of microscale EHD conduction pumps and found that the microscale EHD conduction pumps more easily fall into the saturation regime compared with the macroscale EHD conduction pumps due to the enhanced diffusion effect; in other words, the microscale EHD conduction pumps have a wider saturation regime. We showed that the conduction number C0 could not distinguish the working regime of the microscale EHD conduction pumps because it does not take the diffusion effect into account. By employing the revised expression of heterocharge layer thickness, we proposed a new dimensionless number, C0D to distinguish the working regimes of microscale EHD conduction pumps.

6.
Biomacromolecules ; 24(11): 5467-5477, 2023 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-37862241

RESUMEN

Biofouling due to nonspecific proteins or cells on the material surfaces is a major challenge in a range of applications such as biosensors, medical devices, and implants. Even though poly(ethylene glycol) (PEG) has become the most widely used stealth material in medical and pharmaceutical products, the number of reported cases of PEG-triggered rare allergic responses continues to increase in the past decades. Herein, a new type of antifouling material poly(amine oxide) (PAO) has been evaluated as an alternative to overcome nonspecific foulant adsorption and impart comparable biocompatibility. Alkyl-substituted PAO containing diethyl, dibutyl, and dihexyl substituents are prepared, and their solution properties are studied. Photoreactive copolymers containing benzophenone as the photo-cross-linker are prepared by reversible addition-fragmentation chain-transfer polymerization and fully characterized by gel permeation chromatography and dynamic light scattering. Then, these water-soluble polymers are anchored onto a silicon wafer with the aid of UV irradiation. By evaluating the fouling resistance properties of these modified surfaces against various types of foulants, protein adsorption and bacterial attachment assays show that the cross-linked PAO-modified surface can efficiently inhibit biofouling. Furthermore, human blood cell adhesion experiments demonstrate that our PAO polymer could be used as a novel surface modifier for biomedical devices.


Asunto(s)
Incrustaciones Biológicas , Polímeros , Humanos , Polímeros/farmacología , Polímeros/química , Incrustaciones Biológicas/prevención & control , Óxidos , Aminas , Polietilenglicoles/química , Propiedades de Superficie , Adsorción
7.
J Interv Cardiol ; 2023: 4611602, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37415784

RESUMEN

Objective: To evaluate the value of the cardiac magnetic resonance intravoxel incoherent motion (IVIM) technique in microcirculatory dysfunction in patients with hypertrophic cardiomyopathy (HCM). Methods: The medical records of 19 patients with HCM in our hospital from January 2020 to May 2021 were collected retrospectively, and 23 healthy people with a similar age and gender distribution to the patients with HCM were included as controls. All the included subjects underwent clinical assessment and cardiac magnetic resonance imaging. The original IVIM images were analysed, and the imaging parameters of each segment were measured. The HCM group was divided into non-hypertrophic myocardium and hypertrophic myocardium groups. The differences in imaging parameters between the normal and HCM groups were compared. A Spearman correlation analysis was used to explore the correlation between end-diastolic thickness (EDTH) and each IVIM parameter. Results: The D∗ and f values in the HCM group were lower than those in the normal group (p < 0.0001 and p = 0.004, respectively). The f, D, D∗, and EDTH values of the hypertrophic segment, non-hypertrophic segment, and normal groups were statistically significant (p < 0.05). The difference in D∗ values among the mild, moderate, severe, and very severe HCM groups was statistically significant (p < 0.05). There was a statistically significant difference in EDTH among the mild, moderate, severe, and very severe groups (p < 0.001). There were significant differences in the values of D, D∗, and f between the non-delayed enhancement group and the delayed enhancement group (p < 0.05). The EDTH values of 304 segments in the HCM group were negatively correlated with f (r = -0.219, p = 0.028) and D∗ values (r = -0.310, p < 0.001). Conclusion: The use of IVIM technology can achieve a non-invasive early quantitative assessment of microvascular disease in HCM without the injection of a contrast agent and provide a reference for the early diagnosis of and intervention in myocardial ischemia in patients with HCM.


Asunto(s)
Cardiomiopatía Hipertrófica , Humanos , Estudios Retrospectivos , Microcirculación , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Espectroscopía de Resonancia Magnética
8.
Eur Radiol ; 33(12): 8809-8820, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37439936

RESUMEN

OBJECTIVES: To develop and validate a radiomics-based model (ADGGIP) for predicting adult-type diffuse gliomas (ADG) grade by combining multiple diffusion modalities and clinical and imaging morphologic features. METHODS: In this prospective study, we recruited 103 participants diagnosed with ADG and collected their preoperative conventional MRI and multiple diffusion imaging (diffusion tensor imaging, diffusion kurtosis imaging, neurite orientation dispersion and density imaging, and mean apparent propagator diffusion-MRI) data in our hospital, as well as clinical information. Radiomic features of the diffusion images and clinical information and morphological data from the radiological reports were extracted, and multiple pipelines were used to construct the optimal model. Model validation was performed through a time-independent validation cohort. ROC curves were used to evaluate model performance. The clinical benefit was determined by decision curve analysis. RESULTS: From June 2018 to May 2021, 72 participants were recruited for the training cohort. Between June 2021 and February 2022, 31 participants were enrolled in the prospective validation cohort. In the training cohort (AUC 0.958), internal validation cohort (0.942), and prospective validation cohort (0.880), ADGGIP had good accuracy in predicting ADG grade. ADGGIP was also significantly better than the single-modality prediction model (AUC 0.860) and clinical imaging morphology model (0.841) (all p < .01) in the prospective validation cohort. When the threshold probability was greater than 5%, ADGGIP provided the greatest net benefit. CONCLUSION: ADGGIP, which is based on advanced diffusion modalities, can predict the grade of ADG with high accuracy and robustness and can help improve clinical decision-making. CLINICAL RELEVANCE STATEMENT: Integrated multi-modal predictive modeling is beneficial for early detection and treatment planning of adult-type diffuse gliomas, as well as for investigating the genuine clinical significance of biomarkers. KEY POINTS: • Integrated model exhibits the highest performance and stability. • When the threshold is greater than 5%, the integrated model has the greatest net benefit. • The advanced diffusion models do not demonstrate better performance than the simple technology.


Asunto(s)
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Imagen de Difusión Tensora/métodos , Estudios Prospectivos , Neoplasias Encefálicas/diagnóstico por imagen , Clasificación del Tumor , Estudios Retrospectivos , Glioma/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos
9.
Neuroradiology ; 65(2): 245-256, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36036278

RESUMEN

PURPOSE: To investigate early neurological deficits-related change patterns in gray matter (GM) volume in patients with carbon monoxide poisoning (COP) and GM volume differences between patients with and without delayed neurological sequelae (DNS) and those with and without T2 hyperintense lesions after COP. METHODS: Forty-one COP patients (24 patients with DNS) and 36 sex- and age-matched healthy controls (HC) were enrolled in this study. The neurological assessments were administered within 24 h after MRI scans. Voxel-based morphometry analysis was used to detect regional GM volume change. RESULTS: The COP group had statistically significant GM atrophy in the bilateral prefrontal and temporal lobes, anterior cingulate (ACC), thalamus, posterior cerebellum, and right hippocampus compared to the HC group. Atrophy in the left medial orbital superior frontal gyrus (SFG), bilateral ACC, and bilateral thalamus were related to lower Mini-Mental State Examination (MMSE) scores and higher Unified Parkinson's Disease Rating Scale subsection III and neuro-psychiatric inventory scores. Atrophy in the hippocampus and posterior cerebellum were also related to decrease MMSE scores. The DNS subgroup had greater GM atrophy in the limbic system than the non-DNS subgroup. Compared to the subgroup without T2 hyperintense lesions, greater GM atrophy in the limbic system, motor and visual cortex, and default network was observed in the subgroup with T2 hyperintense lesions. CONCLUSION: GM atrophy in the medial orbital SFG, ACC, thalamus, hippocampus, and posterior cerebellum is associated with early neurological deficits in patients with COP. Greater atrophy occurred in patients with DNS and those with T2 hyperintense lesions.


Asunto(s)
Intoxicación por Monóxido de Carbono , Sustancia Gris , Humanos , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Intoxicación por Monóxido de Carbono/complicaciones , Intoxicación por Monóxido de Carbono/diagnóstico por imagen , Imagen por Resonancia Magnética , Corteza Prefrontal/patología , Atrofia/patología
10.
Neuroradiology ; 65(1): 55-64, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35835879

RESUMEN

PURPOSE: To evaluate two advanced diffusion models, diffusion kurtosis imaging and the newly proposed mean apparent propagation factor-magnetic resonance imaging, in the grading of gliomas and the assessing of their proliferative activity. METHODS: Fifty-nine patients with clinically diagnosed and pathologically proven gliomas were enrolled in this retrospective study. All patients underwent DKI and MAP-MRI scans. Manually outline the ROI of the tumour parenchyma. After delineation, the imaging parameters were extracted using only the data from within the ROI including mean diffusion kurtosis (MK), return-to-origin probability (RTOP), Q-space inverse variance (QIV) and non-Gaussian index (NG), and the differences in each parameter in the classification of glioma were compared. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic performance of these parameters. RESULTS: MK, NG, RTOP and QIV were significantly different amongst the different grades of glioma. MK, NG and RTOP had excellent diagnostic value in differentiating high-grade from low-grade glioma, with largest areas under the curve (AUCs; 0.929, 0.933 and 0.819, respectively; P < 0.01). MK and NG had the largest AUCs (0.912 and 0.904) when differentiating grade II tumours from III tumours (P < 0.01) and large AUCs (0.791 and 0.786) when differentiating grade III from grade IV tumours. Correlation analysis of tumour proliferation activity showed that MK, NG and QIV were strongly correlated with the Ki-67 LI (P < 0.001). CONCLUSION: MK, RTOP and NG can effectively represent the microstructure of these altered tumours. Multimodal diffusion-weighted imaging is valuable for the preoperative evaluation of glioma grade and tumour proliferative activity.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Estudios Retrospectivos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Sensibilidad y Especificidad , Clasificación del Tumor , Glioma/diagnóstico por imagen , Glioma/patología , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética , Proliferación Celular
11.
Int J Mol Sci ; 24(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37895031

RESUMEN

Winter wheat is used as forage at the tillering stage in many countries; however, the regrowth pattern of wheat after mowing remains unclear. In this study, the growth patterns of wheat were revealed through cytological and physiological assessments as well as transcriptome sequencing. The results of agronomic traits and paraffin sections showed that the shoot growth rate increased, but root growth was inhibited after mowing. The submicroscopic structure revealed a decrease in heterochromatin in the tillering node cell and a change in mitochondrial shape in the tillering node and secondary root. Analysis of the transcriptome showed the number of differentially expressed genes (DEGs) involved in biological processes, cellular components, and molecular functions; 2492 upregulated DEGs and 1534 downregulated DEGs were identified. The results of the experimental study showed that mowing induced expression of DEGs in the phenylpropanoid biosynthesis pathway and increased the activity of PAL and 4CL. The upregulated DEGs in the starch and sucrose metabolism pathways and related enzyme activity alterations indicated that the sugar degradation rate increased. The DEGs in the nitrogen metabolism pathway biosynthesis of the amino acids, phenylpropanoid biosynthesis metabolism, and in the TCA pathway also changed after mowing. Hormone content and related gene expression was also altered in the tillering and secondary roots after mowing. When jasmonic acid and ethylene were used to treat the wheat after mowing, the regeneration rate increased, whereas abscisic acid inhibited regrowth. This study revealed the wheat growth patterns after mowing, which could lead to a better understanding of the development of dual-purpose wheat.


Asunto(s)
Perfilación de la Expresión Génica , Triticum , Triticum/metabolismo , Transcriptoma , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas
12.
Molecules ; 28(14)2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37513272

RESUMEN

This study investigated the effects of a modified rice bran arabinoxylan compound (RBAC) as a dietary supplement on the gut microbiota of healthy adults. Ten volunteers supplemented their diet with 1 g of RBAC for six weeks and 3 g of RBAC for another six weeks, with a three-week washout period. Faecal samples were collected every 3 weeks over 21 weeks. Microbiota from faecal samples were profiled using 16S rRNA sequencing. Assessment of alpha and beta microbiota diversity was performed using the QIIME2 platform. The results revealed that alpha and beta diversity were not associated with the experimental phase, interventional period, RBAC dosage, or time. However, the statistical significance of the participant was detected in alpha (p < 0.002) and beta (weighted unifrac, p = 0.001) diversity. Explanatory factors, including diet and lifestyle, were significantly associated with alpha (p < 0.05) and beta (p < 0.01) diversity. The individual beta diversity of six participants significantly changed (p < 0.05) during the interventional period. Seven participants showed statistically significant taxonomic changes (ANCOM W ≥ 5). These results classified four participants as responders to RBAC supplementation, with a further two participants as likely responders. In conclusion, the gut microbiome is highly individualised and modulated by RBAC as a dietary supplement, dependent on lifestyle and dietary intake.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Oryza , Adulto , Humanos , Oryza/genética , ARN Ribosómico 16S/genética , Suplementos Dietéticos , Heces
13.
Angew Chem Int Ed Engl ; 62(22): e202302355, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-36971597

RESUMEN

We report a covalent organic framework (COF) induced seeding strategy to fabricate metal-organic framework (MOF) membranes. Contrary to graphene oxide nuclei-depositing substrate, COF substrate has uniform pore size, high microporosity and abundant functional groups. We designed a series of charged COF nanosheets to induce the formation of ZIF-8@COF nanosheet seeds with high aspect ratio over 150, which were readily processed into a compact and uniform seed layer. The resulting ZIF-8 membranes with thickness down to 100 nm exhibit an ultrahigh C3 H6 /C3 H8 separation performance and superior long-term stability. Our strategy is also validated by fabricating ultrathin ZIF-67 and UiO-66 membranes.

14.
Radiology ; 302(3): 652-661, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34874198

RESUMEN

Background The isocitrate dehydrogenase (IDH) genotype and 1p/19q codeletion status are key molecular markers included in glioma pathologic diagnosis. Advanced diffusion models provide additional microstructural information. Purpose To compare the diagnostic performance of histogram features of multiple diffusion metrics in predicting glioma IDH and 1p/19q genotyping. Materials and Methods In this prospective study, participants were enrolled from December 2018 to December 2020. Diffusion-weighted imaging was performed by using a spin-echo echo-planar imaging sequence with five b values (500, 1000, 1500, 2000, and 2500 sec/mm2) in 30 directions for every b value and one b value of 0. Diffusion metrics of diffusion-tensor imaging (DTI), diffusion-kurtosis imaging (DKI), neurite orientation dispersion and density imaging (NODDI), and mean apparent propagator (MAP) were calculated, and their histogram features were analyzed in regions that included the entire tumor and peritumoral edema. Comparisons between groups were performed according to IDH genotype and 1p/19q codeletion status. Logistic regression analysis was used to predict the IDH and 1p/19q genotypes. Results A total of 215 participants (115 men, 100 women; mean age, 48 years ± 13 [standard deviation]) with grade II (n = 68), grade III (n = 35), and grade IV (n = 112) glioma were included. Among the DTI, DKI, NODDI, MAP, and total diffusion models, there were no significant differences in the areas under the receiver operating characteristic curve (AUCs) for predicting IDH mutations (AUC, 0.76, 0.82, 0.78, 0.81, and 0.82, respectively; P > .05) and 1p/19q codeletion in gliomas with IDH mutations (AUC, 0.83, 0.81, 0.82, 0.83, and 0.88, respectively; P > .05). A regression model with an R2 value of 0.84 was used for the Ki-67 labeling index and histogram features of the diffusion metrics. Conclusion Whole-tumor histogram analysis of multiple diffusion metrics is a promising approach for glioma isocitrate dehydrogenase and 1p/19q genotyping, and the performance of diffusion-tensor imaging is similar to that of advanced diffusion models. Clinical trial registration no. ChiCTR2100048119 © RSNA, 2021 Online supplemental material is available for this article. An earlier incorrect version appeared online. This article was corrected on December 14, 2021.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Imagen de Difusión Tensora/métodos , Glioma/diagnóstico por imagen , Glioma/genética , Isocitrato Deshidrogenasa/genética , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/genética , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Prospectivos
15.
J Magn Reson Imaging ; 56(5): 1505-1512, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35394092

RESUMEN

BACKGROUND: Prenatal quantitative evaluation of myelin is important. However, few techniques are suitable for the quantitative evaluation of fetal myelination. PURPOSE: To optimize a modified Look-Locker inversion recovery (MOLLI) T1 mapping sequence for fetal brain development study. STUDY TYPE: Prospective observational preliminary cohort study. POPULATION: A total of 71 women with normal fetuses divided into mid-pregnancy (gestational age 24-28 weeks, N = 25) and late pregnancy (gestational age > 28 weeks, N = 46) groups. FIELD STRENGTH/SEQUENCE: A 3 T/MOLLI sequence. ASSESSMENT: T1 values were measured in pedunculus cerebri, basal ganglia, thalamus, posterior limb of the internal capsule, temporal white matter, occipital white matter, frontal white matter, and parietal white matter by two radiologists (11 and 16 years of experience, respectively). STATISTICAL TESTS: The Kruskal-Wallis test was used for reginal comparison. For each region of interest (ROI), differences in T1 values between the mid and late pregnancy groups were assessed by the Mann Whitney U test. Pearson correlation coefficients (r) were used to evaluate the correlations between T1 values and gestational age for each ROI. Intraobserver and interobserver agreement was determined by the intraclass correlation coefficient (ICC). A P value <0.05 was considered statistically significant. RESULTS: Interobserver and intraobserver agreements of T1 were good for all ROIs (all ICCs > 0.700). There were significant differences in T1 values between lobal white matter and deep regions, respectively. Significant T1 values differences were found between middle and late pregnancy groups in pedunculus cerebri, basal ganglion, thalamus, posterior limb of the internal capsule, temporal, and occipital white matter. The T1 values showed significantly negative correlations with gestational weeks in pedunculus cerebri (r = -0.80), basal ganglion (r = -0.60), thalamus (r = -0.68), and posterior limb of the internal capsule (r = -0.77). DATA CONCLUSION: The T1 values of fetal brain may be assessed using the MOLLI sequence and may reflect the myelination. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Encéfalo , Vaina de Mielina , Encéfalo/diagnóstico por imagen , Estudios de Cohortes , Femenino , Feto/diagnóstico por imagen , Edad Gestacional , Humanos , Lactante , Imagen por Resonancia Magnética , Embarazo , Reproducibilidad de los Resultados
16.
Eur Radiol ; 32(10): 7295-7306, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36048205

RESUMEN

OBJECTIVE: To develop a quantitative Response Evaluation Criteria in Solid Tumors (qRECIST) for evaluating response to neoadjuvant therapy (nT) in ESCCs relying on multiparametric (mp) MRI. METHODS: Patients with cT2-T4a/N0-N3/M0 ESCC undergoing pre-nT and post-nT esophageal mpMRI before radical resection were prospectively included. Images were reviewed by two experienced radiologists. qRECIST was redefined using four methods including conventional criterion (cRECIST) and three model-dependent RECIST relying on quantitative MRI measurements at pre-nT, post-nT, and delta pre-post nT, respectively. Pathological tumor regression grades (TRGs) were used as a reference standard. The rates of agreement between four qRECIST methods and TRGs were determined with a Cronbach's alpha test, area under the curve (AUC), and a diagnostic odds ratio meta-analysis. RESULTS: Ninety-one patients were enrolled. All four methods revealed high inter-reader agreements between the two radiologists, with a Kappa coefficient of 0.96, 0.87, 0.88, and 0.97 for cRECIST, pre-nT RECIST, post-nT RECIST, and delta RECIST, respectively. Among them, delta RECIST achieved the highest overall agreement rate (67.0% [61/91]) with TRGs, followed by post-nT RECIST (63.8% [58/91]), cRECIST (61.5% [56/91]), and pre-nT RECIST (36.3% [33/91]). Especially, delta RECIST achieved the highest accuracy (97.8% [89/91]) in distinguishing responders from non-responders, with 97.3% (34/35) for responders and 98.2% (55/56) for non-responders. Post-nT RECIST achieved the highest accuracy (93.4% [85/91]) in distinguishing complete responders from non-pCRs, with 77.8% (11/18) for pCRs and 94.5% (69/73) for non-pCRs. CONCLUSION: The qRECIST with mpMRI can assess treatment-induced changes and may be used for early prediction of response to nT in ESCC patients. KEY POINTS: • Quantitative mpMRI can reliably assess tumor response, and delta RECIST model had the best performance in evaluating response to nT in ESCCs, with an AUC of 0.98, 0.95, 0.80, and 0.82 for predicting TRG0, TRG1, TRG2, and TRG3, respectively. • In distinguishing responders from non-responders, the rate of agreement between delta RECIST and pathology was 97.3% (34/35) for responders and 98.2% (55/56) for non-responders, resulting in an overall agreement rate of 97.8% (89/91). • In distinguishing pCRs from non-pCR, the rate of agreement between MRI and pathology was 77.8% (11/18) for pCRs and 94.5% (69/73) for non- pCRs, resulting in an overall agreement rate of 91.2% (83/91).


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Humanos , Terapia Neoadyuvante , Criterios de Evaluación de Respuesta en Tumores Sólidos , Resultado del Tratamiento
17.
Eur Radiol ; 32(9): 5930-5942, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35384460

RESUMEN

OBJECTIVES: To develop and validate an optimal model based on the 1-mm-isotropic-3D contrast-enhanced StarVIBE MRI sequence combined with clinical risk factors for predicting survival in patients with esophageal squamous cell carcinoma (ESCC). METHODS: Patients with ESCC at our institution from 2015 to 2017 participated in this retrospective study based on prospectively acquired data, and were randomly assigned to training and validation groups at a ratio of 7:3. Random survival forest (RSF) and variable hunting methods were used to screen for radiomics features and LASSO-Cox regression analysis was used to build three models, including clinical only, radiomics only and combined clinical and radiomics models, which were evaluated by concordance index (CI) and calibration curve. Nomograms and decision curve analysis (DCA) were used to display intuitive prediction information. RESULTS: Seven radiomics features were selected from 434 patients, combined with clinical features that were statistically significant to construct the predictive models of disease-free survival (DFS) and overall survival (OS). The combined model showed the highest performance in both training and validation groups for predicting DFS ([CI], 0.714, 0.729) and OS ([CI], 0.730, 0.712). DCA showed that the net benefit of the combined model and of the clinical model is significantly greater than that of the radiomics model alone at different threshold probabilities. CONCLUSIONS: We demonstrated that a combined predictive model based on MR Rad-S and clinical risk factors had better predictive efficacy than the radiomics models alone for patients with ESCC. KEY POINTS: • Magnetic resonance-based radiomics features combined with clinical risk factors can predict survival in patients with ESCC. • The radiomics nomogram can be used clinically to predict patient recurrence, DFS, and OS. • Magnetic resonance imaging is highly reproducible in visualizing lesions and contouring the whole tumor.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Supervivencia sin Enfermedad , Neoplasias Esofágicas/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Nomogramas , Estudios Retrospectivos
18.
Cell Mol Biol (Noisy-le-grand) ; 68(2): 153-161, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35869709

RESUMEN

It was to investigate the diagnostic value of keratin 7 (KRT7) in malignant metastasis of epithelial ovarian cancer and benign epithelial ovarian tumors. From January 2018 to January 2019, 30 fresh tissues of benign epithelial ovarian tumors, 30 fresh tissues of borderline tumors, 30 fresh tissues of metastatic ovarian were collected in The First Affiliated Hospital of Fujian Medical University, and 30 fresh tissues of normal ovarian tissues were collected as the control group. Federation of gynecology and obstetrics (FIGO) staging criteria: 25 cases of stage I, 26 cases of stage II, 16 cases of stage III, and 23 cases of stage IV. The relative expression of KRT7 was detected by real-time fluorescence quantitative PCR, and the relationship between KRT7 expression and epithelial ovarian cancer grading was analyzed. The results showed that the positive expression rate of KRT7 was 12.1% in normal ovarian tissues, 28.4% in benign epithelial ovarian tumors, 53.5% in borderline tumors, and 24.2% in metastatic ovarian cancer. With the increase of tumor stage malignancy, the relative expression of KRT7 decreased significantly, but there was no significant difference between stage I and stage II, stage III and stage IV (P > 0.05). The difference between stage I and stage III, and stage IV was significant (P < 0.05). Patients with epithelial ovarian cancer had a significant difference compared with the control group (P < 0.05). In summary, compared with the control group, the expression of KRT7 in patients with benign epithelial ovarian tumors and borderline tumors was significantly decreased. The expression level of KRT7 in benign epithelial ovarian tumors was lower than that in borderline tumors. The expression of KRT7 was related to the occurrence, development, and deterioration of ovarian cancer, which provided a basis for targeted therapy of tumors.


Asunto(s)
Neoplasias Ováricas , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/patología , Femenino , Humanos , Inmunohistoquímica , Queratina-7/genética , Estadificación de Neoplasias , Neoplasias Ováricas/patología
19.
Bioorg Chem ; 125: 105867, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35576739

RESUMEN

Baeyer-Villiger monooxygenase (BVMO) mediated sulfoxidation is a sustainable approach for the synthesis of esomeprazole. In this work, a novel phenylacetone monooxygenase from Limnobacter sp. (LnPAMO) was found to have trace activity for synthesis of enantiopure esomeprazole. Through engineering in the substrate tunnel using a mutagenesis strategy called "nonpolarity paving" and some modifications in cofactor binding domains, a mutant harboring 15 mutations (LnPAMO Mu15) was obtained with 6.6 × 103-fold higher activity to convert omeprazole sulfide into esomeprazole. The activities of the mutant for synthesis of (S)-methyl phenyl sulfoxide and (S)-pantoprazole also increased much, indicating the versatility of the mutant for sulfoxide synthesis. Importantly, no over-oxidation byproduct omeprazole sulfone was detected in the sulfoxidation products by both mass spectrometry and HPLC analysis. Then NADP-dependent Burkholderia stabili formate dehydrogenase was ligated behind Mu15 along with a ribosome binding site sequence in pET-28a for co-expression. By single whole-cell of recombinant Escherichia coli BL21 coexpressing Mu15 and formate dehydrogenase, omeprazole sulfide was efficiently converted into esomeprazole without production of sulfone (16 g/L substrate, enantiomeric excess > 99.9% (S) and > 99% conversion) and the space-time-yield reached 1.67 g product/L/h.


Asunto(s)
Esomeprazol , Oxigenasas de Función Mixta , Acetona/análogos & derivados , Acetona/metabolismo , Escherichia coli/genética , Esomeprazol/metabolismo , Formiato Deshidrogenasas/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Oxidación-Reducción , Especificidad por Sustrato
20.
BMC Pregnancy Childbirth ; 22(1): 349, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35459146

RESUMEN

BACKGROUND: To investigate the diagnostic value of monoexponential, biexponential, and diffusion kurtosis MR imaging (MRI) in differentiating placenta accreta spectrum (PAS) disorders. METHODS: A total of 65 patients with PAS disorders and 27 patients with normal placentas undergoing conventional DWI, IVIM, and DKI were retrospectively reviewed. The mean, minimum, and maximum parameters including the apparent diffusion coefficient (ADC) and exponential ADC (eADC) from standard DWI, diffusion kurtosis (MK), and mean diffusion coefficient (MD) from DKI and pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) from IVIM were measured from the volumetric analysis and compared between patients with PAS disorders and patients with normal placentas. Univariate and multivariated logistic regression analyses were used to evaluate the value of the above parameters for differentiating PAS disorders. Receiver operating characteristics (ROC) curve analyses were used to evaluate the diagnostic efficiency of different diffusion parameters for predicting PAS disorders. RESULTS: Multivariate analysis demonstrated that only D mean and D max differed significantly among all the studied parameters for differentiating PAS disorders when comparisons between accreta lesions in patients with PAS (AP) and whole placentas in patients with normal placentas (WP-normal) were performed (all p < 0.05). For discriminating PAS disorders, a combined use of these two parameters yielded an AUC of 0.93 with sensitivity, specificity, and accuracy of 83.08, 88.89, and 83.70%, respectively. CONCLUSION: The diagnostic performance of the parameters from accreta lesions was better than that of the whole placenta. D mean and D max were associated with PAS disorders.


Asunto(s)
Placenta Accreta , Biomarcadores , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Femenino , Humanos , Placenta Accreta/diagnóstico por imagen , Embarazo , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad
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