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1.
Ultraschall Med ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38802093

RESUMEN

Purpose To investigate the associations between contrast-enhanced ultrasound imaging features and disease recurrence among patients with locally advanced breast cancer treated with neoadjuvant chemotherapy. Materials and Methods In the study, pre- and post-neoadjuvant chemotherapy contrast-enhanced ultrasound images of 43 patients with breast cancer were retrospectively analysed. Post-acquisition image processing involved the placement of freehand-drawn regions of interest, followed by the generation of blood flow kinetics representing blood volume and velocity for these regions of interest. Qualitative and quantitative contrast-enhanced ultrasound parameters were compared to predict recurrence, and receiver operating characteristic analysis was used to evaluate predictive ability. Results Among the 43 patients, 10 (23%) exhibited disease recurrence (median [range]: 27 [4-68] months). Post-neoadjuvant chemotherapy peak enhancement, wash-in area under the curve, wash-out area under the curve, and wash-in and wash-out area under the curve (p=0.003, p=0.004, p=0.026, and p=0.014, respectively) differed between the no-recurrence and recurrence groups. The area under the receiver operating characteristic curve (0.88; 95% confidence interval: 0.75-1.00) for post-neoadjuvant chemotherapy peak enhancement was the highest among the contrast-enhanced ultrasound parameters, with a cut-off of 13.33 arbitrary units. Conclusion Higher peak enhancement on post-neoadjuvant chemotherapy contrast-enhanced ultrasound images were associated with recurrence in women with locally advanced breast cancer and is a potential biomarker of tumour recurrence.

2.
Dement Neurocogn Disord ; 23(2): 115, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38720823

RESUMEN

[This corrects the article on p. 117 in vol. 22, PMID: 37545866.].

3.
ACS Appl Mater Interfaces ; 16(19): 25511-25518, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703111

RESUMEN

Colloidal quantum dots (QDs) are promising candidates for next-generation display technology because of their unique optical properties and have already appeared in the market as a high-end product. On the basis of their extraordinary properties, QD emissions with a given chemical composition can be tailored in a wide spectral window due to quantum size effects, which constitutes a key advantage of QDs in the display field. Specifically, investigations of structure-dependent and composition-dependent characterizations outside the quantum confinement effect have become an important part of practical applications. Therefore, from the perspective of designing nanostructures with well-defined heterointerfaces, strong quantum confinement effects with effective carrier confinement are desirable. Our results show that the photoluminescence (PL) intensity of CdSe/CdZnS core-shell QDs was enhanced 5.7 times compared with that of the CdSe core QDs. Supplementary analytical techniques involving transmission electron microscopy revealed the heterointerface configuration and composition distribution of the core and shell materials. The effects of the heterointerface on carrier dynamics in core-shell QDs were revealed by monitoring wavelength-dependent time-resolved PL. To further develop the QD light-emitting diodes (QD-LEDs), we produced an all-solution processed inverted QD-LEDs using CdSe/CdZnS core-shell QDs as the emitter. The electroluminescence spectrum of deep-red emissive QD-LEDs with CIE chromaticity coordinates of (0.68, 0.32) exhibited a peak at 638 nm.

5.
Nat Commun ; 15(1): 1742, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38453921

RESUMEN

Super Typhoon Mangkhut, which traversed the North Equatorial Current (NEC; 8-17 °N) in the western North Pacific in 2018, was the most intense Category-5 tropical cyclone (TC) with the longest duration in history-3.5 days. Here we show that the combination of two factors-high ocean heat content (OHC) and increased stratification - makes the NEC region the most favored area for a rapid intensification (RI) of super typhoons, instead of the Eddy Rich Zone (17-25 °N), which was considered the most relevant for RI occurrence. The high OHC results from a northward deepening thermocline in geostrophic balance with the westward-flowing NEC. The stratification is derived from precipitation associated with the Inter-Tropical Convergence Zone in the summer peak typhoon season. These factors, which are increasingly significant over the past four decades, impede the TC-induced sea surface cooling, thus enhancing RI of TCs and simultaneously maintaining super typhoons over the NEC region.

6.
Case Rep Oncol ; 17(1): 317-328, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38404405

RESUMEN

Introduction: Breast cancer exhibits vast genomic diversity, leading to varied clinical manifestations. Integrating molecular subtyping with in-depth genomic profiling is pivotal for informed treatment choices and prognostic insights. Whole-genome clinical analysis provides a holistic view of genome-wide variations, capturing structural changes and affirming tumor suppressor gene loss of heterozygosity. Case Presentation: Here we detail four unique breast cancer cases from Seoul St. Mary's Hospital, highlighting the actionable benefits and clinical value of whole-genome sequencing (WGS). As an all-in-one test, WGS demonstrates significant clinical utility in these cases, including: (1) detecting homologous recombination deficiency with underlying somatic causal variants (case 1), (2) distinguishing double primary cancer from metastasis (case 2), (3) uncovering microsatellite instability (case 3), and (4) identifying rare germline pathogenic variants in TP53 gene (case 4). Our observations underscore the enhanced clinical relevance of WGS-based testing beyond pinpointing a few driver mutations in conventional targeted panel sequencing platforms. Conclusion: With genomic advancements and decreasing sequencing costs, WGS stands out as a transformative tool in oncology, paving the way for personalized treatment plans rooted in individual genetic blueprints.

7.
Med Phys ; 51(3): 1985-1996, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37722712

RESUMEN

BACKGROUND: In proton therapy, a highly steep distal dose penumbra can be utilized for dose conformity, given the Bragg peak characteristic of protons. However, the location of the Bragg peak in patients (i.e., the beam range) is very sensitive to range uncertainty. Even a small shift of beam range can produce a significant variation of delivered dose to tumor and normal tissues, thus degrading treatment quality and threatening patient safety. This range uncertainty issue, therefore, is one of the important aspects to be managed in proton therapy. PURPOSE: For better management of range uncertainty, range verification has been widely studied, and prompt gamma imaging (PGI) is considered one of the promising methods in that effort. In this context, a PGI system named the gamma electron vertex imaging (GEVI) system was developed and recently upgraded for application to pencil-beam scanning (PBS) proton therapy. Here, we report the first experimental results using the therapeutic spot scanning proton beams. METHODS: A homogeneous slab phantom and an anthropomorphic phantom were employed. Spherical and cubic planning target volumes (PTVs) were defined. Various range shift scenarios were introduced. Prompt gamma (PG) measurement was synchronized with beam irradiation. The measured PG distributions were aggregated to improve the PG statistics. The range shift was estimated based on the relative change of the centroid in the measured PG distribution. The estimated range shifts were analyzed by range shift mapping, confidence interval (CI) estimation, and statistical hypothesis testing. RESULTS: The range shift mapping results showed an obvious measured range shift tendency following the true shift values. However, some fluctuations were found for spots that had still-low PG statistics after spot aggregation. The 99% CI distributions showed clearly distributed range shift measurement data. The overall accuracy and precision for all investigated scenarios were 0.36 and 0.20 mm, respectively. The results of one-sample t-tests confirmed that every shift scenario could be observed up to 1 mm of shift. The ANOVA results proved that the measured range shift data could be discriminated from one another, except for 16 (of 138) comparison cases having 1-2 mm shift differences. CONCLUSIONS: This study demonstrated the feasibility of the GEVI system for measurement of range shift in spot scanning proton therapy. Our experimental results showed that the proton beam can be measured up to 1 mm of range shift with high accuracy and precision. We believe that the GEVI system is one of the most promising PGI systems for in vivo range verification. Further research for application to more various cases and patient treatments is planned.


Asunto(s)
Terapia de Protones , Humanos , Terapia de Protones/métodos , Electrones , Protones , Planificación de la Radioterapia Asistida por Computador/métodos , Diagnóstico por Imagen , Fantasmas de Imagen , Dosificación Radioterapéutica
8.
Eur J Radiol ; 170: 111251, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38128255

RESUMEN

PURPOSE: This study aims to compare the image quality, apparent diffusion coefficient (ADC), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) values, and scan time between readout-segmented echo planar imaging (rs-EPI) and simultaneous multislice (SMS) rs-EPI sequences. METHODS: A total of 80 consecutive women who underwent breast diffusion-weighted imaging (DWI) were included, and two rs-EPI DWI sequences with and without SMS were acquired and compared. Qualitative analysis involved three radiologists independently scoring image quality and radiologist preference. For quantitative comparison, the radiologists independently measured the ADC values in patients, while SNR, CNR, and ADC values were measured on a phantom. RESULTS: The acquisition time was 5:47 min for rs-EPI and 3:20 min for SMS rs-EPI. In terms of image quality, scores were similar between rs-EPI and SMS rs-EPI sequences in the pooled data set, with the exception of skin-line distinction (p = 0.001) and background noise (p < 0.001). All radiologists considered SMS rs-EPI as equal or superior to rs-EPI in more than 70 % of cases. SMS rs-EPI demonstrated significantly higher ADC values than rs-EPI by all radiologists (p ≤ 0.002). For the phantom measurement, ADC (SMS: 1.26 ± 0.68 and RS: 1.26 ± 0.68, p = 0.198), SNR (SMS: 540.6 ± 342.1 and RS: 558.8 ± 523.2, p = 0.927), and CNR (SMS: 235.5 ± 38.9 and RS: 252.8 ± 108.0, p = 0.784) values did not significantly differ between the two sequences. CONCLUSION: SMS rs-EPI exhibited comparable image quality and similar ADC, SNR, and CNR values to rs-EPI while reducing the scan time by 42%.


Asunto(s)
Mama , Imagen Eco-Planar , Humanos , Femenino , Imagen Eco-Planar/métodos , Mama/diagnóstico por imagen , Relación Señal-Ruido , Imagen de Difusión por Resonancia Magnética/métodos , Fantasmas de Imagen , Reproducibilidad de los Resultados
9.
Int J Mol Sci ; 24(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38139287

RESUMEN

Tagetes erecta and Ocimum basilicum are medicinal plants that exhibit anti-inflammatory effects against various diseases. However, their individual and combined effects on osteoarthritis (OA) are unknown. Herein, we aimed to demonstrate the effects of T. erecta, O. basilicum, and their mixture, WGA-M001, on OA pathogenesis. The administration of total extracts of T. erecta and O. basilicum reduced cartilage degradation and inflammation without causing cytotoxicity. Although WGA-M001 contained lower concentrations of the individual extracts, it strongly inhibited the expression of pathogenic factors. In vivo OA studies also supported that WGA-M001 had protective effects against cartilage destruction at lower doses than those of T. erecta and O. basilicum. Moreover, its effects were stronger than those observed using Boswellia and Perna canaliculus. WGA-M001 effectively inhibited the interleukin (IL)-1ß-induced nuclear factor kappa-light-chain-enhancer of the activated B cell (NF-κB) pathway and ERK phosphorylation. Furthermore, RNA-sequence analysis also showed that WGA-M001 decreased the expression of genes related to the IL-1ß-induced NF-κB and ERK signaling pathways. Therefore, WGA-M001 is more effective than the single total extracts of T. erecta and O. basilicum in attenuating OA progression by regulating ERK and NF-κB signaling. Our results open new possibilities for WGA-M001 as a potential therapeutic agent for OA treatment.


Asunto(s)
Ocimum basilicum , Osteoartritis , Tagetes , FN-kappa B/metabolismo , Tagetes/metabolismo , Condrocitos/metabolismo , Cartílago/metabolismo , Osteoartritis/patología
10.
Korean J Orthod ; 53(6): 420-430, 2023 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-37989578

RESUMEN

Objective: : The purpose of this finite element method (FEM) study was to analyze the biomechanical differences and tooth displacement patterns according to the traction direction, methods, and sites for total distalization of the mandibular dentition using clear aligner treatment (CAT). Methods: : A finite element analysis was performed on four FEM models using different traction methods (via a precision cut hook or button) and traction sites (mandibular canine or first premolar). A distalization force of 1.5 N was applied to the traction site by changing the direction from -30 to +30° to the occlusal plane. The initial tooth displacement and von Mises stress on the clear aligners were analyzed. Results: : All CAT-based total distalization groups showed an overall trend of clockwise or counterclockwise rotation of the occlusal plane as the force direction varied. Mesiodistal tipping of individual teeth was more prominent than that of bodily movements. The initial displacement pattern of the mandibular teeth was more predominant based on the traction site than on the traction method. The elastic deformation of clear aligners is attributed to unintentional lingual tipping or extrusion of the mandibular anterior teeth. Conclusions: : The initial tooth displacement can vary according to different distalization strategies for CAT-based total distalization. Discreet application and biomechanical understanding of traction sites and directions are necessary for appropriate mandibular total distalization.

11.
Orthod Craniofac Res ; 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37792583

RESUMEN

OBJECTIVES: The purpose was to identify the maxillary basal arch forms utilizing the root apices and compare the maxillary basal arch form of groups with cleft lip and palate (CLP) and normal group. MATERIALS AND METHODS: This study included 30 patients (21.8 ± 3.5 years old) with unilateral CLP (ULCP group) and 30 patients (20.9 ± 2.2 years old) with bilateral CLP (BCLP group). The normal group consisted of 30 non-cleft patients (21.2 ± 2.3 years old) with normal occlusion. Three-dimensional (3D) Cartesian coordinates of the root apices of each tooth were determined using cone-beam computed tomography. The 3D coordinates were projected onto the palatal plane to create the 2D coordinates. Thereafter, the basal arch forms were constructed by the Procrustes superimposition. Finally, For the basal arch form comparisons among groups, the inter-root widths were measured. RESULTS: Both CLP groups had a narrower inter-root width than the normal group. The BCLP group had significantly narrower premolar and molar widths than the UCLP group (P < .05). Especially, the inter-first molar width of the UCLP and BCLP groups was 3.7 ± 0.7 (P < .001) and 6.6 ± 0.8 (P < .001) mm smaller than that of the normal group, respectively. CONCLUSIONS: We used the root apices to identify the basal arch forms. The basal arch form of patients with CLP was narrower than that of the normal group. The basal arch form of patients with BCLP was narrower than that of patients with UCLP. Our findings may help clinicians better comprehend basal arch forms in patients with CLP and transverse discrepancies.

13.
J Magn Reson Imaging ; 2023 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-37596823

RESUMEN

BACKGROUND: Deep learning models require large-scale training to perform confidently, but obtaining annotated datasets in medical imaging is challenging. Weak annotation has emerged as a way to save time and effort. PURPOSE: To develop a deep learning model for 3D breast cancer segmentation in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using weak annotation with reliable performance. STUDY TYPE: Retrospective. POPULATION: Seven hundred and thirty-six women with breast cancer from a single institution, divided into the development (N = 544) and test dataset (N = 192). FIELD STRENGTH/SEQUENCE: 3.0-T, 3D fat-saturated gradient-echo axial T1-weighted flash 3D volumetric interpolated brain examination (VIBE) sequences. ASSESSMENT: Two radiologists performed a weak annotation of the ground truth using bounding boxes. Based on this, the ground truth annotation was completed through autonomic and manual correction. The deep learning model using 3D U-Net transformer (UNETR) was trained with this annotated dataset. The segmentation results of the test set were analyzed by quantitative and qualitative methods, and the regions were divided into whole breast and region of interest (ROI) within the bounding box. STATISTICAL TESTS: As a quantitative method, we used the Dice similarity coefficient to evaluate the segmentation result. The volume correlation with the ground truth was evaluated with the Spearman correlation coefficient. Qualitatively, three readers independently evaluated the visual score in four scales. A P-value <0.05 was considered statistically significant. RESULTS: The deep learning model we developed achieved a median Dice similarity score of 0.75 and 0.89 for the whole breast and ROI, respectively. The volume correlation coefficient with respect to the ground truth volume was 0.82 and 0.86 for the whole breast and ROI, respectively. The mean visual score, as evaluated by three readers, was 3.4. DATA CONCLUSION: The proposed deep learning model with weak annotation may show good performance for 3D segmentations of breast cancer using DCE-MRI. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

14.
Life (Basel) ; 13(8)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37629601

RESUMEN

Diffusion-weighted imaging (DWI) utilizing maximum-intensity projection (MIP) was suggested as a cost-effective alternative tool without the risk of gadolinium-based contrast agents. The purpose of this study was to investigate whether DWI MIPs played a supportive role in young (≤60) patients with marked background parenchymal enhancement (BPE) on contrast-enhanced MRI (CE-MRI). The research included 1303 patients with varying degrees of BPE, and correlations between BPE on CE-MRI, the background diffusion signal (BDS) on DWI, and clinical parameters were analyzed. Lesion detection scores were compared between CE-MRI and DWI, with DWI showing higher scores. Among the 186 lesions in 181 patients with marked BPE on CE-MRI, the main lesion on MIPs of CE-MRI was partially or completely seen in 88.7% of cases, while it was not seen in 11.3% of cases. On the other hand, the main lesion on MIPs of DWI was seen in 91.4% of cases, with only 8.6% of cases showing no visibility. DWI achieved higher scores for lesion detection compared to CE-MRI. The presence of a marked BDS was significantly associated with a lower likelihood of a higher DWI score (p < 0.001), and non-mass lesions were associated with a decreased likelihood of a higher DWI score compared with mass lesions (p = 0.196). In conclusion, the inclusion of MIPs of DWI in the preoperative evaluation of breast cancer patients, particularly young women with marked BPE, proved highly beneficial in improving the overall diagnostic process.

15.
J Korean Soc Radiol ; 84(2): 345-360, 2023 Mar.
Artículo en Coreano | MEDLINE | ID: mdl-37051391

RESUMEN

In Korea, the number of institutions providing breast MRI, as well as the number of breast MRIs, has recently increased. However, MRI-guided procedures, including biopsy and needle localization, are rarely performed compared to ultrasound-guided or stereotactic biopsy. As breast MRI has high sensitivity but limited specificity, lesions detected only on MRI require pathologic confirmation through MRI-guided biopsy or surgical excision with MRI-guided needle localization. Thus, we aimed to review MRI-guided procedures, including their indications, techniques, procedural considerations, and limitations.

16.
Korean J Orthod ; 53(2): 99-105, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36960720

RESUMEN

Objective: The study aimed to evaluate the changes in mandibular width after sagittal split ramus osteotomy (SSRO) in patients with mandibular asymmetric prognathism using cone-beam computed tomography (CBCT). Methods: Seventy patients who underwent SSRO for mandibular setback surgery were included in two groups, symmetric (n = 35) and asymmetric (n = 35), which were divided according to the differences in their right and left setback amounts. The mandibular width was evaluated three-dimensionally using CBCT images taken immediately before surgery (T1), 3 days after surgery (T2), and 6 months after surgery (T3). Repeated measures analysis of variance was applied to verify the differences in mandibular width statistically. Results: Both groups showed a significant increase in the mandibular width at T2, followed by a significant decrease at T3. No significant difference was observed between T1 and T3 in any of the measurements. No significant differences were found between the two groups (p > 0.05). Conclusions: After mandibular asymmetric setback surgery using SSRO, the mandibular width increased immediately but returned to its original width 6 months after surgery.

18.
Foods ; 12(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36766037

RESUMEN

This study aimed to investigate and optimize the quality and sensory properties of baked products with lutein-enriched marigold flower powder (MP). Lutein-enriched marigold flowers produced via hydroponic methods using LED lights were used as a functional material in sponge cakes to increase lutein content. MP particles were divided into coarse (Dv50 = 315 µm), fine (Dv50 = 119 µm), and superfine MP (Dv50 = 10 µm) fractions and added to the sponge cake after being designated to control (sponge cake prepared without MP), coarse MPS (sponge cake prepared with coarse MP), fine MPS (sponge cake prepared with fine MP), and superfine MPS (sponge cake prepared with superfine MP) groups. The sizes and surface properties of superfine MP particles were more homogeneous and smoother than the other samples. As the particle size decreased, the specific volume increased, whereas baking loss, hardness, and chewiness of the sponge cake decreased. Superfine MP and superfine MPS had the highest lutein content. The flavor of marigold and the overall acceptability of sponge cake with superfine MP were 7.90 ± 0.97 and 7.55 ± 0.76, which represents the highest values among the samples. The results of this study have shown that jet milling can contribute to improvements in texture, lutein content, and sensory qualities for baked products with MP.

19.
Diagnostics (Basel) ; 13(3)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36766617

RESUMEN

This study aimed to determine whether apparent diffusion coefficient (ADC) and morphological features on diffusion-weighted MRI (DW-MRI) can discriminate metastatic axillary lymph nodes (ALNs) from benign in patients with breast cancer. Two radiologists measured ADC, long and short diameters, long-to-short diameter ratio, and cortical thickness and assessed eccentric cortical thickening, loss of fatty hilum, irregular margin, asymmetry in shape or number, and rim sign of ALNs on DW-MRI and categorized them into benign or suspicious ALNs. Pathologic reports were used as a reference standard. Statistical analysis was performed using the Mann-Whitney U test and chi-square test. Overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of DW-MRI were calculated. The ADC of metastatic ALNs was 0.905 × 10-3 mm2/s, and that of benign ALNs was 0.991 × 10-3 mm2/s (p = 0.243). All morphologic features showed significant difference between the two groups. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy of the final categorization on DW-MRI were 77.1%, 93.3%, 79.4%, 92.5%, and 86.2%, respectively. Our results suggest that morphologic evaluation of ALNs on DWI can discriminate metastatic ALNs from benign. The ADC value of metastatic ALNs was lower than that of benign nodes, but the difference was not statistically significant.

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