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1.
Adv Sci (Weinh) ; : e2400736, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38639415

ABSTRACT

For decreasing the global cost of corrosion, it is essential to understand the intricate mechanisms of corrosion and enhance the corrosion resistance of materials. However, the ambiguity surrounding the dominant mechanism of calcium-magnesium aluminosilicate (CMAS) molten salt corrosion in extreme environments hinders the mix-and-matching of the key rare earth elements for increasing the resistance of monosilicates against corrosion of CMAS. Herein, an approach based on correlated electron microscopy techniques combined with density functional theory calculations is presented to elucidate the complex interplay of competing mechanisms that control the corrosion of CMAS of monosilicates. These findings reveal a competition between thermodynamics and kinetics that relies on the temperatures and corrosion processes. Innovative medium-entropy monosilicates with exceptional corrosion resistance even at 1500 °C are developed. This is achieved by precisely modulating the radii of rare earth ions in monosilicates to strike a delicate balance between the competition in thermodynamics and kinetics. After 50 and 100 h of corrosion, the thinnest reactive layers are measured to be only 28.8 and 35.4 µm, respectively.

2.
Mol Cancer ; 23(1): 54, 2024 03 14.
Article in English | MEDLINE | ID: mdl-38486218

ABSTRACT

BACKGROUND: Phosphoinositide 3-kinases (PI3Ks) are critical regulators of diverse cellular functions and have emerged as promising targets in cancer therapy. Despite significant progress, existing PI3K inhibitors encounter various challenges such as suboptimal bioavailability, potential off-target effects, restricted therapeutic indices, and cancer-acquired resistance. Hence, novel inhibitors that overcome some of these challenges are needed. Here, we describe the characterization of KTC1101, a novel pan-PI3K inhibitor that simultaneously targets tumor cell proliferation and the tumor microenvironment. Our studies demonstrate that KTC1101 significantly increases the anti-PD-1 efficacy in multiple pre-clinical mouse models. METHODS: KTC1101 was synthesized and characterized employing chemical synthesis, molecular modeling, Nuclear Magnetic Resonance (NMR), and mass spectrometry. Its target specificity was confirmed through the kinase assay, JFCR39 COMPARE analysis, and RNA-Seq analysis. Metabolic stability was verified via liver microsome and plasma assays, pharmacokinetics determined by LC-MS/MS, and safety profile established through acute toxicity assays to determine the LD50. The antiproliferative effects of KTC1101 were evaluated in a panel of cancer cell lines and further validated in diverse BALB/c nude mouse xenograft, NSG mouse xenograft and syngeneic mouse models. The KTC1101 treatment effect on the immune response was assessed through comprehensive RNA-Seq, flow cytometry, and immunohistochemistry, with molecular pathways investigated via Western blot, ELISA, and qRT-PCR. RESULTS: KTC1101 demonstrated strong inhibition of cancer cell growth in vitro and significantly impeded tumor progression in vivo. It effectively modulated the Tumor Microenvironment (TME), characterized by increased infiltration of CD8+ T cells and innate immune cells. An intermittent dosing regimen of KTC1101 enhanced these effects. Notably, KTC1101 synergized with anti-PD-1 therapy, significantly boosting antitumor immunity and extending survival in preclinical models. CONCLUSION: KTC1101's dual mechanism of action-directly inhibiting tumor cell growth and dynamically enhancing the immune response- represents a significant advancement in cancer treatment strategies. These findings support incorporating KTC1101 into future oncologic regimens to improve the efficacy of immunotherapy combinations.


Subject(s)
CD8-Positive T-Lymphocytes , Phosphatidylinositol 3-Kinases , Humans , Animals , Mice , Chromatography, Liquid , Tandem Mass Spectrometry , Immunotherapy
3.
Nat Commun ; 15(1): 2141, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38459024

ABSTRACT

Flexible thermoelectric devices show great promise as sustainable power units for the exponentially increasing self-powered wearable electronics and ultra-widely distributed wireless sensor networks. While exciting proof-of-concept demonstrations have been reported, their large-scale implementation is impeded by unsatisfactory device performance and costly device fabrication techniques. Here, we develop Ag2Se-based thermoelectric films and flexible devices via inkjet printing. Large-area patterned arrays with microscale resolution are obtained in a dimensionally controlled manner by manipulating ink formulations and tuning printing parameters. Printed Ag2Se-based films exhibit (00 l)-textured feature, and an exceptional power factor (1097 µWm-1K-2 at 377 K) is obtained by engineering the film composition and microstructure. Benefiting from high-resolution device integration, fully inkjet-printed Ag2Se-based flexible devices achieve a record-high normalized power (2 µWK-2cm-2) and superior flexibility. Diverse application scenarios are offered by inkjet-printed devices, such as continuous power generation by harvesting thermal energy from the environment or human bodies. Our strategy demonstrates the potential to revolutionize the design and manufacture of multi-scale and complex flexible thermoelectric devices while reducing costs, enabling them to be integrated into emerging electronic systems as sustainable power sources.

4.
Res Sq ; 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38464266

ABSTRACT

Background: Segmented regression, a common model for interrupted time series (ITS) analysis, primarily utilizes two equation parametrizations. Interpretations of coefficients vary between the two segmented regression parametrizations, leading to occasional user misinterpretations. Methods: To illustrate differences in coefficient interpretation between two common parametrizations of segmented regression in ITS analysis, we derived analytical results and present an illustration evaluating the impact of a smoking regulation policy in Italy using a publicly accessible dataset. Estimated coefficients and their standard errors were obtained using two commonly used parametrizations for segmented regression with continuous outcomes. We clarified coefficient interpretations and intervention effect calculations. Results: Our investigation revealed that both parametrizations represent the same model. However, due to differences in parametrization, the immediate effect of the intervention is estimated differently under the two approaches. The key difference lies in the interpretation of the coefficient related to the binary indicator for intervention implementation, impacting the calculation of the immediate effect. Conclusions: Two common parametrizations of segmented regression represent the same model but have different interpretations of a key coefficient. Researchers employing either parametrization should exercise caution when interpreting coefficients and calculating intervention effects.

5.
Gynecol Oncol ; 184: 214-223, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38340647

ABSTRACT

BACKGROUND: Failure to deliver guideline-concordant treatment may contribute to disparities among Hispanic/Latinx cervical cancer patients. This study investigated the association between survival rates in Hispanic/Latinx subpopulations and the provision of guideline-concordant care. METHODS: We analyzed patients with primary cervical cancer from 2004 to 2019 (National Cancer Database). We developed nine quality metrics based on FIGO staging (2009). Clinical and demographic covariates were analyzed using Chi-squared tests. Adjusted associations between receipt of guideline-concordant care and races and ethnicities were analyzed using multivariable marginal Poisson regression models. Adjusted Cox proportional hazard models were utilized to evaluate survival probability. RESULTS: A total of 95,589 patients were included. Hispanic/Latinx and Non-Hispanic Black (NHB) populations were less likely to receive guideline-concordant care in four and five out of nine quality metrics, respectively. Nonetheless, the Hispanic/Latinx group exhibited better survival outcomes in seven of nine quality metrics. Compared to Mexican patients, Cuban patients were 1.17 times as likely to receive timely initiation of treatment in early-stage disease (RR 1.17, 95% CI 1.04-1.37, p < 0.001). Puerto Rican and Dominican patients were, respectively, 1.16 (RR 1.16, 95% CI 1.07-1.27, p < 0.001) and 1.19 (RR 1.19, 95% 1.04-1.37, p > 0.01) times as likely to undergo timely initiation of treatment in early-stage disease. Patients of South or Central American (RR 1.18, 95% CI 1.10-1.27, p < 0.001) origin were more likely to undergo timely initiation of treatment in locally advanced disease. CONCLUSION: Significant differences in survival were identified among our cohort despite the receipt of guideline concordant care, with notably higher survival among Hispanic/Latinx populations.

6.
Zhongguo Zhen Jiu ; 44(1): 51-56, 2024 Jan 12.
Article in English, Chinese | MEDLINE | ID: mdl-38191159

ABSTRACT

OBJECTIVES: To compare the clinical effect on Bell's facial palsy in the acute stage between the staging comprehensive treatment with acupuncture-moxibustion and western medication. METHODS: Sixty patients with Bell's facial palsy in the acute stage were randomly divided into an observation group and a control group, with 30 cases in each one. The patients in the control group were administered orally with prednisone acetate tablets and methylcobalamin tablets until the 28th day of illness. In the observation group, the staging comprehensive treatment with acupuncture-moxibustion was adopted. On the affected side, Qianzheng (EX-HN 16), Yifeng (TE 17), Sibai (ST 2), Yangbai (GB 14), Jiache (ST 6), Dicang (ST 4) and Touwei (ST 8), etc. were stimulated. In the acute stage (Day 1 to 7 of illness), the routine acupuncture and the point-toward-point needle insertion were delivered, no any manipulation was exerted at acupoints, and the needles were retained for 30 min. In the subacute stage (Day 8 to 14 of illness), on the base of the treatment as the acute stage, the depth of needle insertion was adjusted at a part of acupoints and the even needling technique was operated by twisting needle. Besides, electroacupuncture (EA) was attached to Qianzheng (EX-HN 16) and Dicang (ST 4), with continuous wave of low intensity and high frequency, 100 Hz, for 20 min. In the recovery stage (Day 15 to 28 of illness), on the base of the treatment as the subacute stage, the heavy stimulation of acupuncture was given, in which, the sticking and lifting needle techniques were delivered after the needles were inserted from Sibai (ST 2) toward Dicang (ST 4), and from Dicang (ST 4) toward Jiache (ST 6), separately; warm needling was operated at Yifeng (TE 17), and EA changed to stimulate the acupoints with the intermittent wave of high intensity and low frequency, 2 Hz, for 30 min. Acupuncture-moxibustion was given once every other day until the end of the 28th day of illness. The level of House-Brackmann facial nerve function rating scale (H-B grade),the score of Sunnybrook facial nerve grading system (Sunnybrook), the score of facial disability index (FDI), the temperature difference in the infrared thermal imaging facial area and electromyogram (EMG) situation of the affected muscle group were observed before and after treatment in the two groups. Using musculoskeletal ultrasound,the facial nerve diameter was detected and the clinical effect was compared between the two groups. RESULTS: After treatment, the level of H-B grade, Sunnybrook score, the scores of physical function and social life function in FDI were improved when compared with those before treatment in the patients of either group (P<0.01, P<0.05), and the results of these evaluations in the observation group were better than those of the control group (P<0.05). After treatment, the temperature difference of the frontal area, the eye area, the zygomatic area and the mouth corner was declined in comparison with that before treatment in the two groups (P<0.05), and the temperature difference in each area in the observation group was lower than that of the control group (P<0.05).The root mean square (RMS) of the frontal muscle group, the zygomatic muscle group and the orbicularis muscle group on the affected side increased in comparison with that before treatment in the two groups (P<0.01), and RMS of the observation group was higher than that of the control group (P<0.05) after treatment. Before treatment, the diameter of the facial nerve on the affected side was larger than that on the healthy side (P<0.01), and after treatment, the diameter on the affected side was reduced when compared with that before treatment in the two groups (P<0.01); the diameter of the facial nerve on the affected side in the observation group was smaller than that of the control group (P<0.05), while, the diameter on the affected side was larger when compared with the healthy side in the control group (P<0.05). The total effective rate of the observation group was 93.3% (28/30), higher than that of the control group (83.3% [25/30], P<0.05). CONCLUSIONS: The staging comprehensive treatment with acupuncture-moxibustion is clearly effective on Bell's facial palsy in the acute stage, which affirms the effectiveness of acupuncture-moxibustion for the acute stage of Bell's facial palsy in comparison with conventional western medication.


Subject(s)
Acupuncture Therapy , Bell Palsy , Facial Paralysis , Moxibustion , Humans , Facial Paralysis/therapy , Bell Palsy/therapy , Face
7.
J Infect Dis ; 229(2): 422-431, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-37531658

ABSTRACT

BACKGROUND: The epidemiology of respiratory viral infections is complex. How infection with one respiratory virus affects risk of subsequent infection with the same or another respiratory virus is not well described. METHODS: From October 2019 to June 2021, enrolled households completed active surveillance for acute respiratory illness (ARI), and participants with ARI self-collected nasal swab specimens; after April 2020, participants with ARI or laboratory-confirmed severe acute respiratory syndrome coronavirus 2 and their household members self-collected nasal swab specimens. Specimens were tested using multiplex reverse-transcription polymerase chain reaction for respiratory viruses. A Cox regression model with a time-dependent covariate examined risk of subsequent detections following a specific primary viral detection. RESULTS: Rhinovirus was the most frequently detected pathogen in study specimens (406 [9.5%]). Among 51 participants with multiple viral detections, rhinovirus to seasonal coronavirus (8 [14.8%]) was the most common viral detection pairing. Relative to no primary detection, there was a 1.03-2.06-fold increase in risk of subsequent virus detection in the 90 days after primary detection; risk varied by primary virus: human parainfluenza virus, rhinovirus, and respiratory syncytial virus were statistically significant. CONCLUSIONS: Primary virus detection was associated with higher risk of subsequent virus detection within the first 90 days after primary detection.


Subject(s)
Enterovirus Infections , Respiratory Syncytial Virus, Human , Respiratory Tract Infections , Virus Diseases , Viruses , Humans , Infant , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/epidemiology , Washington/epidemiology , Viruses/genetics , Rhinovirus/genetics
8.
Cancer Med ; 12(23): 21452-21464, 2023 12.
Article in English | MEDLINE | ID: mdl-37964735

ABSTRACT

BACKGROUND: Hispanic/Latinx people have the second highest cervical cancer incidence rates in the U.S. However, there is a lack of disaggregated data on clinical outcomes for this diverse and populous group, which is critical to direct resources and funding where they are most needed. This study assessed differences in stage at diagnosis of cervical cancer among Hispanic/Latinx subpopulations and associated factors. METHODS: We analyzed patients with primary cervical cancer from 2004 to 2019 in the National Cancer Database. Hispanic/Latinx patients were further categorized into Mexican, Puerto Rican (PR), Cuban, Dominican, and Central/South American, as per standard NCDB categories, and evaluated based on stage at diagnosis and sociodemographic characteristics. Multinomial logistic regression quantified the odds of advanced stage at presentation. Regression models were adjusted for age, education, neighborhood income, insurance status, and additional factors. RESULTS: Hispanic/Latinx cervical cancer patients were more likely to be uninsured (18.9% vs. 6.0%, p < 0.001) and more likely to live in low-income neighborhoods (28.6% vs. 16.9%, p < 0.001) when compared to non-Hispanic White populations. Uninsured Hispanic/Latinx patients had 37.0% higher odds of presenting with regional versus localized disease (OR 1.37; 95% CI, 1.19-1.58) and 47.0% higher odds of presenting with distant versus. Localized disease than insured patients (OR 1.47; 95% CI, 1.33-1.62). When adjusting for age, education, neighborhood income, and insurance status, PR patients were 48% more likely than Mexican patients to present with stage IV versus stage I disease (OR 1.48; 95% CI, 1.34-1.64). CONCLUSION: Disaggregating health data revealed differences in stage at cervical cancer presentation among Hispanic/Latinx subpopulations, with insurance status as a major predictor. Further work targeting structural factors, such as insurance status, within specific Hispanic/Latinx subpopulations is needed.


Subject(s)
Uterine Cervical Neoplasms , Female , Humans , Educational Status , Hispanic or Latino , United States/epidemiology , Uterine Cervical Neoplasms/epidemiology
9.
Influenza Other Respir Viruses ; 17(6): e13166, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37346095

ABSTRACT

Respiratory syncytial virus (RSV) causes disproportionate morbidity and mortality in vulnerable populations. We tested residents of homeless shelters in Seattle, Washington for RSV in a repeated cross-sectional study as part of community surveillance for respiratory viruses. Of 15 364 specimens tested, 35 had RSV detected, compared to 77 with influenza. The most common symptoms for both RSV and influenza were cough and rhinorrhea. Many individuals with RSV (39%) and influenza (58%) reported that their illness significantly impacted their ability to perform their regular activities. RSV and influenza demonstrated similar clinical presentations and burden of illness in vulnerable populations living in congregate settings.


Subject(s)
Ill-Housed Persons , Influenza, Human , Respiratory Syncytial Virus Infections , Respiratory Syncytial Virus, Human , Viruses , Humans , Influenza, Human/epidemiology , Respiratory Syncytial Virus Infections/diagnosis , Washington/epidemiology , Cross-Sectional Studies
10.
Int J Mol Sci ; 24(11)2023 Jun 05.
Article in English | MEDLINE | ID: mdl-37298710

ABSTRACT

Post-intensive care syndrome (PICS) poses a serious threat to the health of intensive care unit (ICU) survivors, and effective treatment options are currently lacking. With increasing survival rates of ICU patients worldwide, there is a rising interest in developing methods to alleviate PICS symptoms. This study aimed to explore the potential of using Hyaluronan (HA) with different molecular weights as potential drugs for treating PICS in mice. Cecal ligation and puncture (CLP) were used to establish a PICS mice model, and high molecular weight HA (HMW-HA) or oligo-HA were used as therapeutic agents. Pathological and physiological changes of PICS mice in each group were monitored. 16S rRNA sequencing was performed to dissect gut microbiota discrepancies. The results showed that both molecular weights of HA could increase the survival rate of PICS mice at the experimental endpoint. Specifically, 1600 kDa-HA can alleviate PICS in a short time. In contrast, 3 kDa-HA treatment decreased PICS model survivability in the early stages of the experiment. Further, via 16S rRNA sequence analysis, we observed the changes in the gut microbiota in PICS mice, thereby impairing intestinal structure and increasing inflammation. Additionally, both types of HA can reverse this change. Moreover, compared to 1600 kDa-HA, 3 kDa-HA can significantly elevate the proportion of probiotics and reduce the abundance of pathogenic bacteria (Desulfovibrionaceae and Enterobacteriaceae). In conclusion, HA holds the advantage of being a potential therapeutic drug for PICS, but different molecular weights can lead to varying effects. Moreover, 1600 kDa-HA showed promise as a protective agent in PICS mice, and caution should be taken to its timing when considering using 3 kDa-HA.


Subject(s)
Gastrointestinal Microbiome , Hyaluronic Acid , Mice , Animals , Molecular Weight , RNA, Ribosomal, 16S/genetics
11.
Ultramicroscopy ; 247: 113697, 2023 May.
Article in English | MEDLINE | ID: mdl-36804629

ABSTRACT

High-resolution electron backscattering diffraction (HR-EBSD) was used to measure rotations and elastic strains by matching diffraction patterns based on cross-correlation. However, the subset-based phase correlation algorithm was unable to determine pattern shifts accurately when large rotations occurred. In this paper, a new matching algorithm was proposed to measure pattern shifts and recover the elastic strain and lattice rotation with finite deformation theory. The algorithm was implemented in two steps: (a) Integral pixel matching: The pixel-related information of the Kikuchi patterns was mapped to the original three-dimensional sphere to obtain the image projected in parallel by using the feature points as the pattern center through the transformation of its spatial coordinates. The correlation between the images projected in parallel before and after deformation was then obtained. The locations of the integral pixels were determined by the peaks of the surface of correlation obtained by traversing all pixels in the search area. (b) subpixel refinement: the locations of subpixels were obtained by FAGN with an appropriate shape function involving rotation and translation. The algorithm was applied to dynamic simulated test sets, and its results were compared with those of the first-pass cross-correlation and the second-pass cross-correlation method with remapping. The proposed method was more robust in the case of rotation and solved the problem that displacement vectors could not be accurately measured when a larger lattice rotation occurred. The mean errors of the measured displacement, rotation, and strain components were 0.02 pixel, 0.5×10-4rad, and 1×10-4, respectively. Compared with the second-pass cross-correlation method, the angle of rotation was more precisely extracted.

12.
Br J Radiol ; 95(1140): 20220367, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36240450

ABSTRACT

OBJECTIVES: To investigate the efficacy of pretreatment ADC and Ki-67 index in the prediction of the response to neoadjuvant chemotherapy (NACT) in advanced olfactory neuroblastoma (ONB) patients. METHODS: A total of 21 advanced ONB patients (mean 43.48 years ± 14.26; range 25-69 years; 13 men and 8 women) with diffusion-weighted imaging (DWI) before NACT between June 2015 and October 2021 were retrospectively analyzed. Patients were categorized into responders and non-responders according to RECIST 1.1 after two cycles of NACT. The clinical data, ADCmean value, and Ki-67 index were analyzed. RESULTS: Kadish stage, ADCmean value, and Ki-67 index showed statistical significance between responders and non-responders. Patients with Kadish C stage were more likely to respond to platinum-based NACT (p = 0.035). Patients with the lower ADCmean value showed response to NACT (p = 0.002) and the cutoff point was 1.04 × 10-3 mm2/s. Patients with the higher Ki-67 index showed response to NACT (p = 0.003) and the cutoff point was 17.5%. Predictive performance of Ki-67 index and ADCmean value showed no significance between responders and non-responders (p = 0.865). A significant negative correlation was found between ADCmean value and Ki-67 index (r = -0.539, p = 0.038). CONCLUSIONS: The pretreatment ADCmean value, Ki-67 index and Kadish stage have the potential to predict the response to NACT in advanced ONB patients. ADVANCES IN KNOWLEDGE: This is the first study that investigated the feasibility of DWI in predicting the response to NACT in ONB patients and showed that Kadish stage, pretreatment ADCmean and Ki-67 index may play an important role in the prediction.


Subject(s)
Esthesioneuroblastoma, Olfactory , Nose Neoplasms , Male , Humans , Female , Neoadjuvant Therapy/methods , Ki-67 Antigen , Retrospective Studies , Esthesioneuroblastoma, Olfactory/diagnostic imaging , Esthesioneuroblastoma, Olfactory/drug therapy , Diffusion Magnetic Resonance Imaging/methods , Nasal Cavity
13.
Ultramicroscopy ; 242: 113623, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36150291

ABSTRACT

A novel approach, termed line-rotated remapping (LRR), for high resolution electron backscatter diffraction is proposed to remap patterns with large rotation. In LRR, the displacements during the first-pass cross-correlation is modified to a function of the corresponding Kikuchi lines and the points on the reference pattern. Then, the finite rotation matrix to remap the test pattern to a similar orientation of the reference pattern is determined using the parameters of the Kikuchi lines. We apply LRR to simulated Si patterns with random orientations, and obtain measurement errors below ∼1.0 × 10-3 for lattice rotations up to ∼26°. The maximum angle that may be remapped by LRR decreases with the distance between the specimen and the screen, which in turn reduces the number of matched Kikuchi lines. We also employ LRR in experiments to quantitatively characterize rotations and elastic strains of a Ni single crystal subject to nanoindentation and tension measurements. Although more experimental data on pattern center and image contrast are required to properly assess the performance of LRR, our method is a promising technique to improve strain measurements in the presence of large rotations.

14.
J Microsc ; 284(3): 256-265, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34633086

ABSTRACT

Partially missing bands in the preset region for Hough transform might strongly affect the accuracy of indexing Kikuchi patterns and reduce the quality of electron backscatter diffraction (EBSD) maps. This paper proposes a novel local band detection method for such kind of low-quality patterns. The approach involves rotating bands to vertical direction, detecting the local line segments through calculating the largest horizontal average grey gradient with a constant interval of 400 pixels in vertical direction, and applying Hough transform as well as weighted averaging to these line clusters to unify the edges of Kikuchi band. Therefore, even if only part of a Kikuchi band is visible, the entire band can also be accurately extracted. The average interplanar angle error obtained by the proposed method is approximately 29.0% less than those obtained by Hough transform-based technique. Moreover, the comparison of mean angular deviation (MAD) is also discussed. The average MAD of this method is about 38.5% lower than that of Hough transform-based technique. Consequently, the local Kikuchi band detection method is expected to be used for post-processing and re-indexing the EBSD low-quality patterns.

15.
Neuroradiology ; 62(9): 1141-1147, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32430642

ABSTRACT

PURPOSE: To evaluate the diagnostic performance of the quantitative parameters derived from diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) MRI in differentiating lacrimal gland pleomorphic adenomas (LGPAs) from lacrimal gland malignant epithelial tumors (LGMETs). METHODS: Seventy-seven cases with LG epithelial tumors confirmed by histopathology (47 LGPAs and 30 LGMETs) underwent DWI and DCE-MRI. The quantitative parameters including the apparent diffusion coefficient (ADC), the volume transfer constant (Ktrans), the efflux rate constant from the extravascular extracellular space (EES) to blood plasma (Kep), and the extravascular extracellular volume fraction (Ve) were used to differentiate LGPAs from LGMETs. Independent-samples t test was conducted to compare these parameters. The diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis. RESULTS: Compared with LGPAs, LGMETs had significantly lower ADC value (1.090 ± 0.169mm2/s) (P < 0.001), higher Ktrans value (0.892 ± 0.517/min) (P = 0.001), and Kep value (1.300 ± 1.131/min) (P = 0.002). ADC as a diagnostic index showed a better diagnostic efficacy in predicting malignant tumors (AUC 0.914, sensitivity 90.0%, specificity 85.1%, and accuracy 87.0%) than Ktrans and Kep alone. The combination of ADC and Ktrans presented the optimal diagnostic performance for the differentiation (AUC 0.938, sensitivity 93.3%, specificity 87.2%, accuracy 89.6%). CONCLUSION: The quantitative parameters including ADC, Ktrans, and Kep derived from DWI and DCE-MRI might be potential imaging biomarkers in differentiating LGPAs from LGMETs. The combination of ADC and Ktrans is superior to other quantitative parameters in distinguishing LGPAs from LGMETs.


Subject(s)
Adenoma, Pleomorphic/diagnostic imaging , Carcinoma/diagnostic imaging , Lacrimal Apparatus Diseases/diagnostic imaging , Multiparametric Magnetic Resonance Imaging , Adult , Contrast Media , Diagnosis, Differential , Diffusion Magnetic Resonance Imaging , Female , Gadolinium DTPA , Humans , Male , Retrospective Studies , Sensitivity and Specificity
16.
J Magn Reson Imaging ; 51(4): 1045-1052, 2020 04.
Article in English | MEDLINE | ID: mdl-31617290

ABSTRACT

BACKGROUND: Retinoblastomas (RBs) with postlaminar optic nerve invasion (PLONI) increases the risk of local recurrence or systemic metastasis. Most MRI studies on PLONI focused on optic nerve enhancement and tumor size, with reported relatively high specificity (84-98%) but low sensitivity (37-78%), which shows room for improvement, especially with regard to sensitivity. PURPOSE: To evaluate the diagnostic performance for detecting PLONI with RB using MRI features. STUDY TYPE: Retrospective. POPULATION: Fifty patients with histopathologic PLONI and 70 patients without PLONI of RB. FIELD STRENGTH/SEQUENCE: 1.5T and 3.0T, precontrast axial T1 -weighted and T2 -weighted, postcontrast axial, coronal and oblique-sagittal T1 -weighted. ASSESSMENT: The eyes were histopathologically analyzed and the preoperative MRI features of the eyes were independently evaluated by three observers. STATISTICAL TESTS: MRI features suggesting the presence of PLONI were identified by univariate and multivariable analysis. Receiver operating characteristic curve (ROC) and the area under the curve (AUC) were used to analyze diagnostic performance. RESULTS: Significant independent diagnostic factors for PLONI include: 1: Bilateral tumor (odds ratio [OR], 15.32; 95% confidence interval [CI]: 1.63-143.51); 2: Tumor with total coverage of the optic disk (OR, 6.43; 95% CI: 1.04-39.79); and 3: Optic nerve enhancement (OR, 8.43; 95% CI: 3.50-20.31). On the other hand, isointense signal of tumor on T2 WI (OR, 0.30; 95% CI: 0.12-0.75) was an independent diagnostic factor in excluding PLONI. ROC analysis showed AUC of 0.84 (95% CI: 0.77-0.91, P < 0.0001) for PLONI. Based on the cutoff of maximum Youden index, the sensitivity, specificity, and accuracy were 82%, 73%, and 77%, respectively. DATA CONCLUSION: MRI features of RB showed a strong association with PLONI. The model of MRI features demonstrated promising diagnostic performance in detecting PLONI. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:1045-1052.


Subject(s)
Retinal Neoplasms , Retinoblastoma , Humans , Magnetic Resonance Imaging , Neoplasm Invasiveness , Neoplasm Recurrence, Local , Optic Nerve/diagnostic imaging , Retinal Neoplasms/diagnostic imaging , Retinoblastoma/diagnostic imaging , Retrospective Studies
17.
Microsc Res Tech ; 81(10): 1203-1207, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30365200

ABSTRACT

A major challenge when performing scanning electron microscopy and X-ray analysis on many ceramic materials is their electrical insulation properties, which leads to buildup of the surface charge and reduced contrast in the secondary electron image. A new procedure was established to quantitatively determine the neutral state values, E1 and E2 , of yttrium aluminum garnet (YAG) ceramics using the Duane-Hunt limit (EDHL ) of Bremsstrahlung, in order to eliminate this charge effect. Thirty-eight EDHL values were linearly fitted with the last portion of X-ray spectra acquired under the incident energy, E0 , from 0.35 to 5.0 kV. According to the distribution of EDHL , two piecewise linear fitting was first employed with a breakpoint of 1.0 kV. Consequently, two intersection points of 0.54 and 2.48 kV, which correspond to E1 and E2 for YAG ceramics, were directly determined using a theoretical curve (EDHL = E0 ). As a result, the high-resolution images of the YAG ceramic grain structure were successfully obtained using the calculated E1 and E2 values.

18.
J Magn Reson Imaging ; 45(4): 998-1004, 2017 04.
Article in English | MEDLINE | ID: mdl-27648498

ABSTRACT

PURPOSE: To identify magnetic resonance imaging (MRI) features of sinonasal rhabdomyosarcoma in adults, including diffusion-weighted (DW) and dynamic contrast-enhanced (DCE) MRI features as compared with carcinomas. MATERIALS AND METHODS: Sixty-four patients were included in this study, including 12 sinonasal rhabdomyosarcomas and 52 sinonasal carcinomas. MRI was completed in all 64 patients with a 3T MR scanner. Conventional MR (nonenhanced and static contrast-enhanced) imaging features, DCE-MRI parameters, and the apparent diffusion coefficients (ADCs) were analyzed by two authors independently (X.Y.W. and Y.Z.W.). RESULTS: Compared with gray matter, sinonasal rhabdomyosarcomas appeared isointense on T1 -weighted images in 11 cases (91.7%, 11 of 12), and hyperintense on T2 -weighted images in 9 patients (75%, 9 of 12). After contrast, sinonasal rhabdomyosarcomas showed inhomogeneous enhancement in 10 cases (83.3%, 10 of 12). Skull involvement was found in eight patients (66.7%) with rhabdomyosarcomas. On T2 -weighted images, sinonasal carcinomas demonstrated isointense in 31 cases (59.6%, 31/52), hyperintense in 14 (26.9%, 14/52), and hypointense in 7 (13.5%, 7/52). Skull involvement was detected in 14 cases (14/52, 26.9%). There were significant differences in T2 signal intensity (P = 0.005) and skull involvement (P = 0.016) between sinonasal rhabdomyosarcoma and carcinomas. There was a marginal difference in time to peak enhancement (P = 0.061), while no difference in time to maximum enhancement (P = 0.403), maximum contrast index (P = 0.368), and time-intensity curve types (P = 0.138) between rhabdomyosarcoma and carcinomas. The ADCs of sinonasal rhabdomyosarcoma were significantly lower than those of sinonasal carcinomas (P < 0.001). CONCLUSION: A multiparametric approach using conventional MRI with added ADCs had the potential to improve the diagnostic accuracy of sinonasal rhabdomyosarcoma in adults. Evidence level: 4 J. Magn. Reson. Imaging 2017;45:998-1004.


Subject(s)
Carcinoma/diagnostic imaging , Magnetic Resonance Imaging/methods , Nose Neoplasms/diagnostic imaging , Paranasal Sinuses/diagnostic imaging , Rhabdomyosarcoma/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Reproducibility of Results , Young Adult
19.
Microsc Res Tech ; 79(9): 814-9, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27338247

ABSTRACT

In the present work, ultra-high-strength steels with multiphase microstructures containing martensite and bainite were prepared by controlling the cooling rate. A new approach was proposed for quantitatively statistical phase analysis using electron backscatter diffraction (EBSD) based on the band contrast which correlates to the quality and intensity of the diffraction patterns. This approach takes advantage of the inherently greater lattice imperfections of martensite, such as dislocations and low-angle grain boundaries, relative to that of bainite. These can reduce the intensity and quality of the EBSD patterns of martensite, which decrease the band contrast. Thus, combined with morphological observations, Gaussian two-peak fitting was employed to analyze the band contrast profile and confirm the ranges of band contrast for the two phases. The volume fractions of bainite and martensite in different samples were determined successfully. In addition, the results show that increased cooling rates improve the proportion of martensite and the ratio of martensite to bainite. Microsc. Res. Tech. 79:814-819, 2016. © 2016 Wiley Periodicals, Inc.

20.
J Comput Assist Tomogr ; 39(6): 860-5, 2015.
Article in English | MEDLINE | ID: mdl-26359585

ABSTRACT

PURPOSE: The purpose of the study was to explore the characteristic magnetic resonance imaging (MRI) findings of schwannoma of the sinonasal tract. METHODS: Eighteen patients with histopathologically confirmed sinonasal schwannoma underwent conventional MRI, and 12 had dynamic contrast-enhanced MRI studies synchronously. The morphology feature, signal intensity, enhancement degree, and time intensity curve (TIC) pattern of schwannomas were retrospectively analyzed. RESULTS: This entity appeared as a well-circumscribed, oval or fusiform soft tissue mass with a mean greatest diameter of 38 mm. Schwannomas exhibited isointense on T1-weighted image in 12 patients and hypointense in 6. On T2-weighted image, the lesions were heterogeneously isointense in 14 patients and hyperintense in 4. The lesions had heterogeneously moderate and marked contrast enhancement in 2 and 16, respectively. The mottled-, island-, and multicyst-like appearance were identified in 3, 4, and 11, respectively. Compared with inverted papilloma and lobular capillary hemangioma, the type I TIC is characteristic of schwannoma. CONCLUSIONS: A well-circumscribed mass displaying T2 intermediate signal intensity, marked enhancement, and type I TIC, with cystic changes, strongly suggests the diagnosis of sinonasal schwannoma.


Subject(s)
Magnetic Resonance Imaging , Neurilemmoma/pathology , Nose Neoplasms/pathology , Nose/pathology , Adult , Aged , Contrast Media , Female , Humans , Image Enhancement , Male , Middle Aged , Retrospective Studies , Young Adult
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