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1.
Radiol Med ; 2024 Jul 13.
Article in English | MEDLINE | ID: mdl-38997568

ABSTRACT

BACKGROUND: The accurate identification of microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) is of great clinical importance. PURPOSE: To develop a radiomics nomogram based on susceptibility-weighted imaging (SWI) and T2-weighted imaging (T2WI) for predicting MVI in early-stage (Barcelona Clinic Liver Cancer stages 0 and A) HCC patients. MATERIALS AND METHODS: A prospective cohort of 189 participants with HCC was included for model training and testing, and an additional 34 participants were enrolled for external validation. ITK-SNAP was used to manually segment the tumour, and PyRadiomics was used to extract radiomic features from the SWI and T2W images. Variance filtering, student's t test, least absolute shrinkage and selection operator regression and random forest (RF) were applied to select meaningful features. Four machine learning classifiers, including K-nearest neighbour, RF, logistic regression and support vector machine-based models, were established. Independent clinical and radiological risk factors were also determined to establish a clinical model. The best radiomics and clinical models were further evaluated in the validation set. In addition, a nomogram was constructed from the radiomic model and independent clinical factors. Diagnostic efficacy was evaluated by receiver operating characteristic curve analysis with fivefold cross-validation. RESULTS: AFP levels greater than 400 ng/mL [odds ratio (OR) 2.50; 95% confidence interval (CI) 1.239-5.047], tumour diameter greater than 5 cm (OR 2.39; 95% CI 1.178-4.839), and absence of pseudocapsule (OR 2.053; 95% CI 1.007-4.202) were found to be independent risk factors for MVI. The areas under the curve (AUCs) of the best radiomic model were 1.000 and 0.882 in the training and testing cohorts, respectively, while those of the clinical model were 0.688 and 0.6691. In the validation set, the radiomic model achieved better diagnostic performance (AUC = 0.888) than the clinical model (AUC = 0.602). The combination of clinical factors and the radiomic model yielded a nomogram with the best diagnostic performance (AUC = 0.948). CONCLUSION: SWI and T2WI-derived radiomic features are valuable for noninvasively and accurately identifying MVI in early-stage HCC. Furthermore, the integration of radiomics and clinical factors yielded a predictive nomogram with satisfactory diagnostic performance and potential clinical benefits.

2.
Eur Radiol ; 33(3): 1737-1745, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36380196

ABSTRACT

OBJECTIVES: To investigate the value of pre-treatment quantitative synthetic MRI (SyMRI) for predicting a good response to neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer. METHODS: This prospective study enrolled 63 patients with locally advanced rectal cancer scheduled to undergo preoperative chemoradiotherapy from January 2019 to June 2021. T1 relaxation time (T1), T2 relaxation time (T2), proton density (PD) from synthetic MRI, and apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) were measured. Independent-sample t-test, the Mann-Whitney U test, the Delong test, and receiver operating characteristic curve (ROC) analyses were used to predict the pathologic complete response (pCR) and T-downstaging. RESULTS: Among the 63 patients, 19 (30%) achieved pCR and 44 (70%) did not, and 24 (38%) achieved T-downstaging, while 44 (62%) did not. The mean T1 and T2 values were significantly lower in the pCR group compared with those in the non-pCR group and in the T-downstage group compared with those in the non-T-downstage group (all p < 0.05). There were no significant differences in the PD and ADC values between the two groups. There were no significant differences between the mean values of T1 and T2 for predicting pCR after CRT (AUC, 0.767 vs. 0.831, p = 0.37). There were no significant differences between the AUC values of T1 and T2 values for the assessment of post-CRT T-downstaging (AUC, 0.746 vs. 0.820, p = 0.506). CONCLUSIONS: In patients with locally advanced rectal cancer, the synthetic MRI-derived T1 relaxation time and T2 relaxation time values are promising imaging markers for predicting a good response to neoadjuvant chemoradiotherapy. KEY POINTS: • Mean T1 and T2 values were significantly lower in the pathologic complete response group and the T-downstage group. • There were no significant differences in the proton density and apparent diffusion coefficient values between the two groups.


Subject(s)
Neoadjuvant Therapy , Rectal Neoplasms , Humans , Prospective Studies , Protons , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/therapy , Rectal Neoplasms/pathology , Treatment Outcome , Magnetic Resonance Imaging , Diffusion Magnetic Resonance Imaging/methods , Chemoradiotherapy
3.
Environ Res ; 204(Pt A): 111949, 2022 03.
Article in English | MEDLINE | ID: mdl-34478720

ABSTRACT

Photocatalysis is regarded as one of the most effective strategies for the removal of the toxic organic pollutants from aqueous solutions. However, a lack of the efficient photocatalysts prevents the widespread practical application. Herein, the electrostatic self-assembly method has been designed for facile synthesis of a novel BaSnO3/PDDA/MXene (BSO/P/MX) nanocomposite as high efficient photocatalyst. In this nanocomposite, the BaSnO3 (BSO), poly (dimethyl-diallylammonium chloride) (PDDA) and MXene (Ti3C2Tx) act as the active species, structure stabilizer and efficient electron transfer medium, respectively. Due to the strong synergy of the nanocomposite, the electron-transferring ability as well as the charge separation efficiency is boosted and thus high catalytic activity achieves towards the photodegradation of 4-nitrophenol. The superior degradation rate of 98.8% and a rate constant K of 0.09113 min-1 have been realized within 75 min of ultraviolet (UV) light irradiation over the BSO/P/MX-8% catalyst. This as-prepared nanocomposite with the excellent catalytic activity can be employed as a promising photocatalyst for treating the organic pollutants from aqueous solutions.


Subject(s)
Nanocomposites , Catalysis , Nitrophenols , Photolysis , Static Electricity
4.
Eur Radiol ; 30(5): 2454-2462, 2020 May.
Article in English | MEDLINE | ID: mdl-32002636

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate the clinical outcome of patients receiving microwave ablation (MWA), either after downstaging of hepatocellular carcinoma (HCC) with transarterial chemoembolization (TACE), or without downstaging when meeting initially the Milan criteria. METHODS: From January 2012 to January 2018, 66 patients with HCC beyond the Milan criteria who were downstaged by TACE previous to MWA comprised the study group. The control group comprised 190 patients who underwent MWA as first-line treatment as they met initially the Milan criteria. Cumulative overall survival (OS) and recurrence-free survival (RFS) rates were compared. The propensity score analysis was performed to reduce potential bias. RESULTS: Baseline characteristics were balanced between the two groups after 1:1 propensity score matching. The OS rates were 100%, 79%, and 73% at 1, 3, and 5 years in the downstaging group and 95%, 83%, and 72%, respectively, in the Milan group. The corresponding RFS rate were 77%, 40%, and 31% in the downstaging group and 76%, 45%, and 34% in the Milan group. There were no significant differences in the OS and RFS rates between the two groups (p = 0.981 and p = 0.586). CONCLUSIONS: The long-term therapeutic outcomes of MWA for downstaged HCC with TACE were similar to HCC that initially met the Milan criteria. KEY POINTS: • Patients treated with MWA of HCC after downstaging with transarterial chemoembolization (TACE) were similar to those with HCC that initially met Milan criteria. • Microwave ablation (MWA) can be an effective treatment for hepatocellular carcinoma (HCC) that is downstaged to the Milan criteria.


Subject(s)
Carcinoma, Hepatocellular/therapy , Liver Neoplasms/therapy , Microwaves/therapeutic use , Propensity Score , Radiofrequency Therapy/methods , Survival Rate/trends , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/mortality , Female , Humans , Liver Neoplasms/diagnosis , Liver Neoplasms/mortality , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed , Treatment Outcome
5.
Jpn J Clin Oncol ; 50(5): 602-608, 2020 May 05.
Article in English | MEDLINE | ID: mdl-31943047

ABSTRACT

OBJECTIVES: Postoperative recurrences, especially anastomotic recurrence and regional lymph node recurrence were common in patients even with curative esophageal cancer surgery. Endobronchial ultrasound-guided transbronchial needle aspiration is an alternative to mediastinoscopy in patients with lung cancer and mediastinal lymphadenopathy. The aim of our study is to evaluate the utility of endobronchial ultrasound-guided transbronchial needle aspiration in postoperative patients suffered from esophageal malignancy. METHODS: All endobronchial ultrasound-guided transbronchial needle aspiration cases performed between August 2015 and December 2018 in our center were all retrospective reviewed. The patients with enlarged mediastinal lymph node and/or unknown intrathoracic mass after esophageal cancer surgery were enrolled. Final diagnoses were determined by the result of endobronchial ultrasound-guided transbronchial needle aspiration, second surgery and/or clinical follow-up for at least 6 months. RESULTS: Overall 29 patients were included in the analysis with 30 lesions sampled. No endobronchial ultrasound-guided transbronchial needle aspiration related complications were observed. In total, 22 of these (73.3%) had a diagnosis of tumor recurrence, whereas eight (26.7%) had a different diagnosis: two (6.7%) had a second primary malignancy and three (10.0%) had non-neoplastic diagnosis. Cases were false-negative in 3 (10.0%) out of 30 lesions. The overall sensitivity, negative predicted value and diagnostic accuracy were 88.9, 50.0 and 90.0%, respectively. CONCLUSIONS: Given its safety, low invasiveness, high sensitivity and diagnostic accuracy, endobronchial ultrasound-guided transbronchial needle aspiration could be considered for mediastinal lymphadenopathy and intrathoracic masses of unknown origin in patients after radical esophageal cancer resection, and its strategic role in the management of these patients was confirmed.


Subject(s)
Endoscopic Ultrasound-Guided Fine Needle Aspiration , Esophageal Neoplasms/diagnosis , Esophageal Neoplasms/surgery , Esophagus/pathology , Esophagus/surgery , Neoplasm Recurrence, Local/pathology , Aged , Esophageal Neoplasms/diagnostic imaging , Esophageal Neoplasms/pathology , Esophagus/diagnostic imaging , Female , Humans , Lung Neoplasms/pathology , Lymph Nodes/pathology , Male , Mediastinoscopy , Middle Aged , Retrospective Studies , Ultrasonography
6.
Radiol Med ; 125(7): 647-653, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32072391

ABSTRACT

INTRODUCTION: To determine the value of whole-tumor histogram analysis of apparent diffusion coefficient (ADC) maps in differentiating nasopharyngeal carcinoma (NPC) from lymphoma (NPL) at the primary site METHOD AND MATERIALS: One hundred forty-seven patients with nasopharyngeal tumors (89 NPCs and 38 NPLs) who had undergone magnetic resonance imaging (MRI) and diffusion-weighted imaging were retrospectively analyzed. ADC histogram-derived parameters were compared between the NPC and NPL groups by using the Mann-Whitney U test. Receiver operating characteristic (ROC) curves of the histogram parameters were plotted for diagnostic accuracy. Sensitivity and specificity were calculated for each histogram parameter. RESULTS: In whole-tumor histogram analysis, the mean, median, and 10th and 25th percentiles of ADC were all significantly higher in NPC than NPL (P = 0.045, P = 0.035, P = 0.005, and P = 0.016, respectively). Uniformity was significantly higher in NPC than NPL (P = 0.001). Skewness was significantly lower in NPC than NPL (P = 0.039). For the conventional ROI-based method, ADCmean values were significantly higher in NPC than in NPL (P = 0.009). The ROC curve analysis showed that uniformity yielded the largest area under the curve (AUC = 0.768) for differentiating NPC from NPL among all ADC metrics, followed by 10th percentiles of ADC (AUC = 0.725); sensitivity and specificity were 76.5% and 71.4%, respectively. CONCLUSION: Whole-tumor histogram analysis of ADC maps could be helpful for differentiating NPC from NPL.


Subject(s)
Diffusion Magnetic Resonance Imaging/methods , Lymphoma/diagnostic imaging , Nasopharyngeal Carcinoma/diagnostic imaging , Nasopharyngeal Neoplasms/diagnostic imaging , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Humans , Lymphoma/pathology , Male , Middle Aged , Nasopharyngeal Carcinoma/pathology , Nasopharyngeal Neoplasms/pathology , Retrospective Studies , Sensitivity and Specificity
7.
Radiology ; 293(3): 707-715, 2019 12.
Article in English | MEDLINE | ID: mdl-31638492

ABSTRACT

Background Transarterial chemoembolization (TACE) is an effective downstaging procedure for hepatocellular carcinoma (HCC). However, knowledge of the effectiveness of radiofrequency ablation (RFA) after downstaging of HCC is currently lacking. Purpose To evaluate the clinical outcomes of RFA after downstaging of HCC by using TACE. Materials and Methods This retrospective study investigated a cohort of patients who underwent RFA with curative intent after downstaging with TACE to meet Milan criteria (one lesion up to 5 cm or no more than three lesions ≤3 cm without vascular invasion or extrahepatic metastasis) from January 2012 to July 2017. A control group of patients initially meeting the Milan criteria also underwent RFA as first-line treatment in the same period. Overall survival (OS), disease-free survival (DFS), and major complication rates were compared by using the log-rank test. To reduce potential bias, a propensity score analysis was also performed. Results There were 72 patients (median age, 56.5 years; range, 30-78 years; 67 men) in the downstaging group and 357 patients meeting the Milan criteria (median age, 58.0 years; range, 25-87 years; 313 men) included in this study. After propensity score matching, the 1-, 3-, and 5-year OS rates were 99%, 80%, and 66%, respectively, for the patients in the downstaging group and 94%, 84%, and 69%, respectively, for the patients in the Milan criteria group. The 1-, 3-, and 5-year DFS rate were 73%, 34%, and 24% for the downstaging group and 74%, 43%, and 37% for the Milan criteria group. There were no differences in the OS, DFS, or major complication rates between the two groups (P = .74, P = .39, P = .73, respectively). Conclusion The long-term patient survival and major complication rates of radiofrequency ablation following transarterial chemoembolization downstaging for hepatocellular carcinoma were similar to that of patients initially meeting the Milan criteria. © RSNA, 2019 See also the editorial by vanSonnenberg and Mueller in this issue.


Subject(s)
Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/surgery , Chemoembolization, Therapeutic , Liver Neoplasms/drug therapy , Liver Neoplasms/surgery , Radiofrequency Ablation , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/pathology , Female , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/pathology , Male , Middle Aged , Neoplasm Staging , Propensity Score , Retrospective Studies , Survival Rate , Tomography, X-Ray Computed
8.
BMC Cancer ; 19(1): 470, 2019 May 17.
Article in English | MEDLINE | ID: mdl-31101029

ABSTRACT

BACKGROUND: To explore prognostic value of the pre-treatment primary lesion apparent diffusion coefficient (ADC) in locoregionally advanced nasopharyngeal carcinoma (LA-NPC). METHODS: A total of 843 patients with newly diagnosed LA-NPC were enrolled from January 2011 to April 2014 and divided into two groups based on ADC values: the low-ADC group and high-ADC group. The 3-year local relapse-free survival (LRFS), distant metastasis free survival (DMFS), disease-free survival (DFS) and overall survival (OS) rates between two groups were compared using Kaplan-Meier curve, and Cox regression analyses were performed to test prognostic value of the pretreatment ADC in LA-NPC. RESULTS: The cut-off value of the pretreatment ADC for predicting local relapse was 784.5 × 10- 6 mm2/s (AUC [area under curve] = 0.604; sensitivity = 0.640; specificity = 0.574), thus patients were divided into low-ADC (< 784.5 × 10- 6; n = 473) group and high-ADC (≥784.5 × 10- 6; n = 370) group. The low-ADC group had significantly higher 3-year LRFS rate and DFS rate than the high-ADC group (LRFS: 96.2% vs. 91.4%, P = 0.003; DFS: 81.4% vs. 73.0%, P = 0.0056). Multivariate analysis showed that the pretreatment ADC is an independent prognostic factor for LRFS (HR, 2.04; 95% CI, 1.13-3.66; P = 0.017) and DFS (HR, 1.41; 95% CI, 1.04-1.89; P = 0.024). CONCLUSIONS: The pretreatment ADC of the primary lesion is an independent prognostic factor for LRFS and DFS in LA-NPC patients.


Subject(s)
Diffusion Magnetic Resonance Imaging , Nasopharyngeal Carcinoma/diagnosis , Nasopharyngeal Neoplasms/diagnosis , Adolescent , Adult , Aged , Child , Disease-Free Survival , Female , Humans , Male , Middle Aged , Prognosis , Retrospective Studies , Young Adult
9.
Mar Drugs ; 17(12)2019 Dec 12.
Article in English | MEDLINE | ID: mdl-31842317

ABSTRACT

As filter-feeding animals mainly ingesting microalgae, bivalves could accumulate paralytic shellfish toxins (PSTs) produced by harmful algae through diet. To protect themselves from the toxic effects of PSTs, especially the concomitant oxidative damage, the production of superoxide dismutase (SOD), which is the only eukaryotic metalloenzyme capable of detoxifying superoxide, may assist with toxin tolerance in bivalves. To better understand this process, in the present study, we performed the first systematic analysis of SOD genes in bivalve Chlamys farreri, an important aquaculture species in China. A total of six Cu/Zn-SODs (SOD1-6) and two Mn-SODs (SOD7, SOD8) were identified in C. farreri, with gene expansion being revealed in Cu/Zn-SODs. In scallops exposed to two different PSTs-producing dinoflagellates, Alexandrium minutum and A. catenella, expression regulation of SOD genes was analyzed in the top ranked toxin-rich organs, the hepatopancreas and the kidney. In hepatopancreas, which mainly accumulates the incoming PSTs, all of the six Cu/Zn-SODs showed significant alterations after A. minutum exposure, with SOD1, 2, 3, 5, and 6 being up-regulated, and SOD4 being down-regulated, while no significant change was detected in Mn-SODs. After A. catenella exposure, up-regulation was observed in SOD2, 4, 6, and 8, and SOD7 was down-regulated. In the kidney, where PSTs transformation occurs, SOD4, 5, 6, and 8 were up-regulated, and SOD7 was down-regulated in response to A. minutum feeding. After A. catenella exposure, all the Cu/Zn-SODs except SOD1 were up-regulated, and SOD7 was down-regulated in kidney. Overall, in scallops after ingesting different toxic algae, SOD up-regulation mainly occurred in the expanded Cu/Zn-SOD group, and SOD6 was the only member being up-regulated in both toxic organs, which also showed the highest fold change among all the SODs, implying the importance of SOD6 in protecting scallops from the stress of PSTs. Our results suggest the diverse function of scallop SODs in response to the PST-producing algae challenge, and the expansion of Cu/Zn-SODs might be implicated in the adaptive evolution of scallops or bivalves with respect to antioxidant defense against the ingested toxic algae.


Subject(s)
Dinoflagellida/physiology , Pectinidae/genetics , Superoxide Dismutase/genetics , Animals , Down-Regulation , Gene Expression Regulation, Enzymologic , Genome , Up-Regulation
10.
Proc Natl Acad Sci U S A ; 113(30): 8460-5, 2016 07 26.
Article in English | MEDLINE | ID: mdl-27402763

ABSTRACT

Brain and heart pathologies are caused by editing defects of transfer RNA (tRNA) synthetases, which preserve genetic code fidelity by removing incorrect amino acids misattached to tRNAs. To extend understanding of the broader impact of synthetase editing reactions on organismal homeostasis, and based on effects in bacteria ostensibly from small amounts of mistranslation of components of the replication apparatus, we investigated the sensitivity to editing of the vertebrate genome. We show here that in zebrafish embryos, transient overexpression of editing-defective valyl-tRNA synthetase (ValRS(ED)) activated DNA break-responsive H2AX and p53-responsive downstream proteins, such as cyclin-dependent kinase (CDK) inhibitor p21, which promotes cell-cycle arrest at DNA damage checkpoints, and Gadd45 and p53R2, with pivotal roles in DNA repair. In contrast, the response of these proteins to expression of ValRS(ED) was abolished in p53-deficient fish. The p53-activated downstream signaling events correlated with suppression of abnormal morphological changes caused by the editing defect and, in adults, reversed a shortened life span (followed for 2 y). Conversely, with normal editing activities, p53-deficient fish have a normal life span and few morphological changes. Whole-fish deep sequencing showed genomic mutations associated with the editing defect. We suggest that the sensitivity of p53 to expression of an editing-defective tRNA synthetase has a critical role in promoting genome integrity and organismal homeostasis.


Subject(s)
Amino Acyl-tRNA Synthetases/metabolism , DNA Damage , Tumor Suppressor Protein p53/metabolism , Zebrafish Proteins/metabolism , Zebrafish/metabolism , Amino Acyl-tRNA Synthetases/genetics , Animals , Embryo, Nonmammalian/embryology , Embryo, Nonmammalian/metabolism , Female , Gene Expression Regulation, Developmental , Male , Mutation , RNA Editing , Tumor Suppressor Protein p53/genetics , Zebrafish/embryology , Zebrafish/genetics , Zebrafish Proteins/genetics
11.
PLoS Genet ; 10(6): e1004409, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24967584

ABSTRACT

Spinster (Spin) in Drosophila or Spinster homolog 1 (Spns1) in vertebrates is a putative lysosomal H+-carbohydrate transporter, which functions at a late stage of autophagy. The Spin/Spns1 defect induces aberrant autolysosome formation that leads to embryonic senescence and accelerated aging symptoms, but little is known about the mechanisms leading to the pathogenesis in vivo. Beclin 1 and p53 are two pivotal tumor suppressors that are critically involved in the autophagic process and its regulation. Using zebrafish as a genetic model, we show that Beclin 1 suppression ameliorates Spns1 loss-mediated senescence as well as autophagic impairment, whereas unexpectedly p53 deficit exacerbates both of these characteristics. We demonstrate that 'basal p53' activity plays a certain protective role(s) against the Spns1 defect-induced senescence via suppressing autophagy, lysosomal biogenesis, and subsequent autolysosomal formation and maturation, and that p53 loss can counteract the effect of Beclin 1 suppression to rescue the Spns1 defect. By contrast, in response to DNA damage, 'activated p53' showed an apparent enhancement of the Spns1-deficient phenotype, by inducing both autophagy and apoptosis. Moreover, we found that a chemical and genetic blockage of lysosomal acidification and biogenesis mediated by the vacuolar-type H+-ATPase, as well as of subsequent autophagosome-lysosome fusion, prevents the appearance of the hallmarks caused by the Spns1 deficiency, irrespective of the basal p53 state. Thus, these results provide evidence that Spns1 operates during autophagy and senescence differentially with Beclin 1 and p53.


Subject(s)
Apoptosis Regulatory Proteins/antagonists & inhibitors , Lysosomes/metabolism , Membrane Proteins/genetics , Tumor Suppressor Protein p53/genetics , Vacuolar Proton-Translocating ATPases/metabolism , Zebrafish Proteins/antagonists & inhibitors , Zebrafish Proteins/genetics , Aging/genetics , Animals , Apoptosis Regulatory Proteins/genetics , Autophagy/genetics , Beclin-1 , DNA Damage/genetics , DNA Repair/genetics , Enzyme Inhibitors/pharmacology , Gene Knockdown Techniques , Green Fluorescent Proteins/genetics , Lysosomes/genetics , Macrolides/pharmacology , Mitochondria/genetics , Mitochondria/metabolism , Vacuolar Proton-Translocating ATPases/antagonists & inhibitors , Zebrafish
12.
Talanta ; 271: 125658, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38219325

ABSTRACT

As a biogenic calcium carbonate, the seashell plays a crucial role in marine environmental studies. In these studies, it is essential to investigate the composition of the seashell. In this study, we used laser-induced breakdown spectroscopy (LIBS) to analyze the elemental composition of cultured scallop-shell (Patinopecten yessoensis), with a specific focus on examining the organic elements (C, N, O, H) to track the shell organic matrix (SOM). Our findings indicate that the seashell organic layer can be accurately identified by referencing the strong emission of nitrogen or the low signal of calcium. To further confirm the presence of this layer, we employed fluorescence spectroscopy, Raman spectroscopy and FTIR spectroscopy. Correlation analysis revealed a strong connection between LIBS emissions (H, O, CC) and seashell organics, as well as demonstrated the presence of organics in metallic emissions (Si, Ba). However, when we conducted elemental mapping on the shell cross-section, the distribution similarity was observed between the elements N, Ba, and Sr. Based on the correlation of organics and the distribution similarity, it is concluded that barium is an element associated with the SOM. These results highlight the potential of LIBS for organic analysis, which can complement traditional seashell analysis.

13.
Neuro Oncol ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991556

ABSTRACT

BACKGROUND: Artificial intelligence has been proposed for brain metastasis (BM) segmentation but it has not been fully clinically validated. The aim of this study was to develop and evaluate a system for BM segmentation. METHODS: A deep-learning-based BM segmentation system (BMSS) was developed using contrast-enhanced MR images from 488 patients with 10,338 brain metastases. A randomized crossover, multi-reader study was then conducted to evaluate the performance of the BMSS for BM segmentation using data prospectively collected from 50 patients with 203 metastases at five centers. Five radiology residents and five attending radiologists were randomly assigned to contour the same prospective set in assisted and unassisted modes. Aided and unaided Dice similarity coefficients (DSCs) and contouring times per lesion were compared. RESULTS: The BMSS alone yielded a median DSC of 0.91 (95% confidence interval, 0.90-0.92) in the multi-center set and showed comparable performance between the internal and external sets (p = 0.67). With BMSS assistance, the readers increased the median DSC from 0.87 (0.87-0.88) to 0.92 (0.92-0.92) (p < 0.001) with a median time saving of 42% (40-45%) per lesion. Resident readers showed a greater improvement than attending readers in contouring accuracy (improved median DSC, 0.05 [0.05-0.05] vs. 0.03 [0.03-0.03]; p < 0.001), but a similar time reduction (reduced median time, 44% [40-47%] vs. 40% [37-44%]; p = 0.92) with BMSS assistance. CONCLUSIONS: The BMSS can be optimally applied to improve the efficiency of brain metastasis delineation in clinical practice.

14.
Hortic Res ; 10(9): uhad162, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37731861

ABSTRACT

Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea, cacao, and coffee, but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear. Here, we report a novel transcription factor Camellia sinensis Senescnece 40 (CsS40) as a caffeine biosynthesis regulator, which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase (TCS1) promoter. Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays, a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter. Consistently, immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells. The expression pattern of CsS40 in 'Fuding Dabai' developing leaves was opposite to that of TCS1; and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels, respectively. The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of 'Fuding Dabai'. Furthermore, overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants, meanwhile, increased their susceptibility to aging. CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors. Taken together, we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar 'Fuding Dabai'. The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.

15.
Neuro Oncol ; 25(3): 544-556, 2023 03 14.
Article in English | MEDLINE | ID: mdl-35943350

ABSTRACT

BACKGROUND: Errors have seldom been evaluated in computer-aided detection on brain metastases. This study aimed to analyze false negatives (FNs) and false positives (FPs) generated by a brain metastasis detection system (BMDS) and by readers. METHODS: A deep learning-based BMDS was developed and prospectively validated in a multicenter, multireader study. Ad hoc secondary analysis was restricted to the prospective participants (148 with 1,066 brain metastases and 152 normal controls). Three trainees and 3 experienced radiologists read the MRI images without and with the BMDS. The number of FNs and FPs per patient, jackknife alternative free-response receiver operating characteristic figure of merit (FOM), and lesion features associated with FNs were analyzed for the BMDS and readers using binary logistic regression. RESULTS: The FNs, FPs, and the FOM of the stand-alone BMDS were 0.49, 0.38, and 0.97, respectively. Compared with independent reading, BMDS-assisted reading generated 79% fewer FNs (1.98 vs 0.42, P < .001); 41% more FPs (0.17 vs 0.24, P < .001) but 125% more FPs for trainees (P < .001); and higher FOM (0.87 vs 0.98, P < .001). Lesions with small size, greater number, irregular shape, lower signal intensity, and located on nonbrain surface were associated with FNs for readers. Small, irregular, and necrotic lesions were more frequently found in FNs for BMDS. The FPs mainly resulted from small blood vessels for the BMDS and the readers. CONCLUSIONS: Despite the improvement in detection performance, attention should be paid to FPs and small lesions with lower enhancement for radiologists, especially for less-experienced radiologists.


Subject(s)
Brain Neoplasms , Humans , Prospective Studies , ROC Curve , Brain Neoplasms/diagnostic imaging , Magnetic Resonance Imaging/methods , Computers , Sensitivity and Specificity
16.
Quant Imaging Med Surg ; 12(7): 3580-3591, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35782274

ABSTRACT

Background: Numerous factors are related to the prognosis of rectal cancer, including T stage, N stage, metastasis, extramural venous invasion (EMVI), circumferential resection margin (CRM), and tumor differentiation. However, it is still a challenge to precisely evaluate them before therapy; therefore, we investigate whether synthetic magnetic resonance imaging and apparent diffusion coefficient (ADC) values could help predict the prognostic factors of rectal cancer. Methods: Eighty-seven patients (55 men and 32 women; mean age, 59±11 years) with pathologically confirmed rectal cancer were enrolled. Preoperative quantitative metrics, including T1, T2, proton density (PD), and ADC values, were measured with diffusion-weighted imaging (DWI) acquired by a single-shot echo-planar sequence and synthetic magnetic resonance imaging acquired by a multi-dynamic multi-echo sequence at 3.0 T, in patients with rectal cancer by two radiologists. We evaluated the diagnostic performance of synthetic magnetic resonance imaging using the independent sample t-test or Mann-Whitney U test and receiver operating characteristic (ROC) curve and multivariate logistic regression analyses and compared the area under the ROC curve of quantitative values using the DeLong test. Results: The T2 and PD values showed a significant reduction among patients with poor differentiation and lymph node metastasis in rectal cancer. The area under the ROC curve values of T2 and PD values for predicting magnetic resonance imaging N stage and differentiation were 0.734, 0.682, and 0.673, 0.686, respectively. Moreover, combining T2 and PD values for magnetic resonance imaging N stage slightly improved the area under the ROC curve value of 0.774 (95% CI, 0.673-0.876). In the present study, the ADC and T1 values were not significant in the differentiation or clinical stage of rectal cancer (RC). Conclusions: Quantitative T2 and PD values obtained by synthetic magnetic resonance imaging might be used for evaluating prognostic factors of rectal cancer noninvasively. Furthermore, combining T2 and PD values further improved the diagnostic performance of magnetic resonance imaging N staging in rectal cancer. The ADC and T1 values were not significant in the differentiation or clinical stage of RC.

17.
J Colloid Interface Sci ; 615: 69-78, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35124507

ABSTRACT

Engineering of electromagnetic wave absorbing materials featuring long-term durability in harsh outdoor environments (e.g., humidity, acid, and alkali conditions) is meaningful for their effective and sustainable implementation. Herein, morphology-controlled erbium oxide-reduced graphene oxide composites are designed for effective absorption of electromagnetic microwaves either in an acidic or alkaline environment. The engineered nanocomposites with chrysanthemum-like structures display good impedance matching, moderate attenuation constant, exchange resonance, natural resonance, multiple reflections, and polarization relaxations, therefore exhibiting excellent microwave absorption capacity with a minimum reflection loss of -37.18 dB and an effective absorption bandwidth of 5.1 GHz. In addition, the chrysanthemum-like composite also displays self-cleaning property, strong weatherability, and acid- and alkali-resistance, enabling sustained electromagnetic wave absorbing performance even in corrosive conditions (1 M HCl, 1 M NaOH). The findings indicate that, through structural engineering, erbium oxide-reduced graphene oxide composites can serve as a promising microwave absorber in harsh outdoor environments.


Subject(s)
Microwaves , Nanocomposites , Erbium , Graphite , Hydrophobic and Hydrophilic Interactions , Oxides
18.
Abdom Radiol (NY) ; 47(6): 2014-2022, 2022 06.
Article in English | MEDLINE | ID: mdl-35368206

ABSTRACT

PURPOSE: Restriction spectrum imaging (RSI) is a novel diffusion MRI model that separates water diffusion into several microscopic compartments. The restricted compartment correlating to the tumor cellularity is expected to be a potential indicator of rectal cancer aggressiveness. Our aim was to assess the ability of RSI model for rectal tumor grading. METHODS: Fifty-eight patients with different rectal cancer grading confirmed by biopsy were involved in this study. DWI acquisitions were performed using single-shot echo-planar imaging (SS-EPI) with multi-b-values at 3 T. We applied a three-compartment RSI model, along with ADC model and diffusion kurtosis imaging (DKI) model, to DWI images of 58 patients. ROC and AUC were used to compare the performance of the three models in differentiating the low grade (G1 + G2) and high grade (G3). Mean ± standard deviation, ANOVA, ROC analysis, and correlation analysis were used in this study. RESULTS: The volume fraction of restricted compartment C1 from RSI was significantly correlated with grades (r = 0.403, P = 0.002). It showed significant difference between G1 and G3 (P = 0.008) and between G2 and G3 (P = 0.01). As for the low-grade and high-grade discrimination, significant difference was found in C1 (P < 0.001). The AUC of C1 for differentiation between low-grade and high-grade groups was 0.753 with a sensitivity of 72.0% and a specificity of 70.0%. CONCLUSION: The three-compartment RSI model was able to discriminate the rectal cancer of low and high grades. The results outperform the traditional ADC model and DKI model in rectal cancer grading.


Subject(s)
Diffusion Magnetic Resonance Imaging , Rectal Neoplasms , Diffusion Magnetic Resonance Imaging/methods , Diffusion Tensor Imaging/methods , Humans , Neoplasm Grading , ROC Curve , Rectal Neoplasms/diagnostic imaging , Rectal Neoplasms/pathology , Sensitivity and Specificity
19.
Nat Ecol Evol ; 6(12): 1891-1906, 2022 12.
Article in English | MEDLINE | ID: mdl-36280781

ABSTRACT

Contrary to classic theory prediction, sex-chromosome homomorphy is prevalent in the animal kingdom but it is unclear how ancient homomorphic sex chromosomes avoid chromosome-scale degeneration. Molluscs constitute the second largest, Precambrian-originated animal phylum and have ancient, uncharacterized homomorphic sex chromosomes. Here, we profile eight genomes of the bivalve mollusc family of Pectinidae in a phylogenetic context and show 350 million years sex-chromosome homomorphy, which is the oldest known sex-chromosome homomorphy in the animal kingdom, far exceeding the ages of well-known heteromorphic sex chromosomes such as 130-200 million years in mammals, birds and flies. The long-term undifferentiation of molluscan sex chromosomes is potentially sustained by the unexpected intertwined regulation of reversible sex-biased genes, together with the lack of sexual dimorphism and occasional sex chromosome turnover. The pleiotropic constraint of regulation of reversible sex-biased genes is widely present in ancient homomorphic sex chromosomes and might be resolved in heteromorphic sex chromosomes through gene duplication followed by subfunctionalization. The evolutionary dynamics of sex chromosomes suggest a mechanism for 'inheritance' turnover of sex-determining genes that is mediated by translocation of a sex-determining enhancer. On the basis of these findings, we propose an evolutionary model for the long-term preservation of homomorphic sex chromosomes.


Subject(s)
Biological Evolution , Sex Chromosomes , Animals , Phylogeny , Sex Chromosomes/genetics , Genome , Sex Characteristics , Mammals/genetics
20.
Front Physiol ; 12: 633301, 2021.
Article in English | MEDLINE | ID: mdl-33613325

ABSTRACT

Inhibitors of apoptosis proteins (IAPs) are conserved regulators involved in cell cycle, cell migration, cell death, immunity and inflammation, should be due to the fact that they can assist with the ability to cope with different kinds of extrinsic or intrinsic stresses. Bivalve molluscs are well adapted to highly complex marine environments. As free-living filter feeders that may take toxic dinoflagellates as food, bivalves can accumulate and put up with significant levels of paralytic shellfish toxins (PSTs). PSTs absorption and accumulation could have a deleterious effect on bivalves, causing negative impact on their feeding and digestion capabilities. In the present study, we analyzed IAP genes (PyIAPs) in Yesso scallop (Patinopecten yessoensis), a major fishery and aquaculture species in China. Forty-seven PyIAPs from five sub-families were identified, and almost half of the PyIAP genes were localized in clusters on two chromosomes. Several sites under positive selection was revealed in the significantly expanded sub-families BIRC4 and BIRC5. After exposure to PST-producing dinoflagellates, Alexandrium catenella, fourteen PyIAPs showed significant responses in hepatopancreas and kidney, and more than eighty-five percent of them were from the expanded sub-families BIRC4 and BIRC5. The regulation pattern of PyIAPs was similar between the two tissues, with more than half exhibited expression suppression within three days after exposure. In contrast to hepatopancreas, more acute changes of PyIAPs expression could be detected in kidney, suggesting the possible involvement of these PyIAPs in tissue-specific PST tolerance. These findings also imply the adaptive expansion of bivalve IAP genes in response to algae derived biotoxins.

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