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Deep learning networks are state-of-the-art approaches for 3D brain image segmentation, and the radiological characteristics extracted from tumors are of great significance for clinical diagnosis, treatment planning, and treatment outcome evaluation. However, two problems have been the hindering factors in brain image segmentation techniques. One is that deep learning networks require large amounts of manually annotated data. Another issue is the computational efficiency of 3D deep learning networks. In this study, we propose a vector quantization (VQ)-based 3D segmentation method that employs a novel unsupervised 3D deep embedding clustering (3D-DEC) network and an efficiency memory reserving-and-fading strategy. The VQ-based 3D-DEC network is trained on volume data in an unsupervised manner to avoid manual data annotation. The memory reserving-and-fading strategy beefs up model efficiency greatly. The designed methodology makes deep learning-based model feasible for biomedical image segmentation. The experiment is divided into two parts. First, we extensively evaluate the effectiveness and robustness of the proposed model on two authoritative MRI brain tumor databases (i.e., IBSR and BrainWeb). Second, we validate the model using real 3D brain tumor data collected from our institute for clinical practice significance. Results show that our method (without data manual annotation) has superior accuracy ( 0.74 ± 0.04 Tanimoto coefficient on IBSR, 97.5% TP and 97.7% TN on BrainWeb, and 91% Dice, 88% sensitivity and 87% specificity on real brain data) and remarkable efficiency (speedup ratio is 18.72 on IBSR, 31.16 on BrainWeb, 31.00 on real brain data) compared to the state-of-the-art methods. The results show that our proposed model can address the lacks of manual annotations, and greatly increase computation speedup with competitive segmentation accuracy compared to other state-of-the-art 3D CNN models. Moreover, the proposed model can be used for tumor treatment follow-ups every 6 months, providing critical details for surgical and postoperative treatment by correctly extracting numerical radiomic features of tumors. [ABSTRACT FROM AUTHOR]

Lobectomy is an effective and well-established therapy for localized lung cancer. This study aimed to assess the lung and lobe change after lobectomy and predict the postoperative lung volume. The study included 135 lung cancer patients from two hospitals who underwent lobectomy (32, right upper lobectomy (RUL); 31, right middle lobectomy (RML); 24, right lower lobectomy (RLL); 26, left upper lobectomy (LUL); 22, left lower lobectomy (LLL)). We initially employ a convolutional neural network model (nnU-Net) for automatically segmenting pulmonary lobes. Subsequently, we assess the volume, effective lung volume (ELV), and attenuation distribution for each lobe as well as the entire lung, before and after lobectomy. Ultimately, we formulate a machine learning model, incorporating linear regression (LR) and multi-layer perceptron (MLP) methods, to predict the postoperative lung volume. Due to the physiological compensation, the decreased TLV is about 10.73%, 8.12%, 13.46%, 11.47%, and 12.03% for the RUL, RML, RLL, LUL, and LLL, respectively. The attenuation distribution in each lobe changed little for all types of lobectomy. LR and MLP models achieved a mean absolute percentage error of 9.8% and 14.2%, respectively. Radiological findings and a predictive model of postoperative lung volume might help plan the lobectomy and improve the prognosis. [ABSTRACT FROM AUTHOR]

Enhancing the capacity and awareness of individuals in disaster prevention and mitigation requires an intuitive and comprehensible method for representing flood hazard education knowledge. To address the challenges of complex information transfer and limited knowledge expression in flood disaster education, this paper proposes a novel strategy. The approach utilizes conceptual graphs to organize and guide the visual representation of flood disaster knowledge. It involves connecting flood data and knowledge elements using concept nodes and relationships, and translating them into dynamic visual representations through instantiation methods. A prototype system was developed to visualize disaster data obtained from flood-affected areas. The visualization output was compared to expert-based reports using a questionnaire, focusing on attractiveness and comprehensibility. The results demonstrated the superiority of our approach, with higher scores of 0.433 and 0.22 (on a scale of 0–1) for attractiveness and comprehensibility, respectively. This highlights the effectiveness of our approach in displaying flood knowledge and facilitating its dissemination. In summary, this paper introduces a comprehensive and dynamic visualization approach for the entire flood process, integrating relevant disaster knowledge. It presents a fresh perspective on digital disaster education tailored to floods, aiming to enhance public awareness of flood risk prevention. [ABSTRACT FROM AUTHOR]

Existing literature increasingly identifies the effect of CEO passion on firm innovation. However, the understanding on how and when CEO passion promotes firm innovation remains limited. We examine the role of the top management team (TMT) creativity as the intervening mechanism in the link between CEO passion and firm innovation, and explore the different roles of flexibility-oriented and control-oriented cultures as contingencies. By using survey data of 245 firms in China, we find that flexibility-oriented culture positively moderates the relationship between CEO passion and TMT creativity, but negatively moderates the relationship between TMT creativity and firm innovation. By contrast, control-oriented culture negatively moderates the relationship between CEO passion and TMT creativity, and insignificantly moderates the relationship between TMT creativity and firm innovation. We also discuss our theoretical contributions and provide some practical implications. [ABSTRACT FROM AUTHOR]

Existing research has established leadership antecedents of team voice behavior. However, the content of team voice has not been distinguished, and limited findings have been generated about the effect of relational leadership, leader-member exchange (LMX), on team voice. Drawing on conservation of resource theory, this research explores the unique and interactive effects of LMX mean and LMX differentiation on promotive and prohibitive team voice. Two multisource studies (Study 1: 293 members and 51 leaders; Study 2: 524 members and 90 leaders) have been conducted to examine the hypotheses. Both studies have revealed that LMX mean is positively related to promotive team voice, and LMX differentiation is negatively related to prohibitive team voice. In addition, LMX differentiation weakens the effect of LMX mean on prohibitive team voice. Study 2 has further verified that LMX differentiation strengthens the effect of LMX mean on promotive team voice. Findings have demonstrated the significant and complex influence of team LMX on team voice. We suggest that team leaders can improve LMX mean and reduce LMX differentiation to encourage team voice behavior. [ABSTRACT FROM AUTHOR]

Detection and segmentation of abnormalities on medical images is highly important for patient management including diagnosis, radiotherapy, response evaluation, as well as for quantitative image research. We present a fully automated pipeline for the detection and volumetric segmentation of non-small cell lung cancer (NSCLC) developed and validated on 1328 thoracic CT scans from 8 institutions. Along with quantitative performance detailed by image slice thickness, tumor size, image interpretation difficulty, and tumor location, we report an in-silico prospective clinical trial, where we show that the proposed method is faster and more reproducible compared to the experts. Moreover, we demonstrate that on average, radiologists & radiation oncologists preferred automatic segmentations in 56% of the cases. Additionally, we evaluate the prognostic power of the automatic contours by applying RECIST criteria and measuring the tumor volumes. Segmentations by our method stratified patients into low and high survival groups with higher significance compared to those methods based on manual contours. Correct interpretation of computer tomography (CT) scans is important for the correct assessment of a patient's disease but can be subjective and timely. Here, the authors develop a system that can automatically segment the non-small cell lung cancer on CT images of patients and show in an in silico trial that the method was faster and more reproducible than clinicians. [ABSTRACT FROM AUTHOR]

Background: Callispheres® microspheres (CSM) are the first drug-eluting bead (DEB) product developed in China; meanwhile, DEB-transarterial chemoembolization (TACE) with CSM is effective and safe in the treatment of hepatocellular carcinoma and intrahepatic cholangiocarcinoma. However, the data regarding the role of irinotecan-eluting beads-TACE (DEBIRI-TACE) using CSM for colorectal cancer liver metastases (CRLM) treatment is limited. Therefore, the present study aimed to investigate the efficacy and safety of DEBIRI-TACE using CSM in the patients with unresectable CRLM. Methods: Totally, 42 unresectable CRLM patients treated with DEBIRI-TACE using CSM were continuously enrolled in this study. Postoperative treatment response (including complete response rate (CR), objective response rate (ORR), and disease control rate (DCR)), survival data (overall survival (OS)), liver function, and adverse events were documented during the follow-up. Results: CR, ORR, and DCR were 19.0%, 92.9%, and 100.0%, respectively, at month (M) 1; were 23.8%, 92.9%, and 97.6%, respectively, at M3; then were 14.3%, 78.6%, and 90.5%, respectively at M6. Regarding survival profiles, 1-year OS was 81.0%; 2-year OS was 58.5%; median OS was 25.0 months (95%CI: 19.3–30.7 months). Additionally, ALT and AST experienced an obviously increased trend at 4 days, but a declined trend at 7 days, while ALB and TBIL had no obvious change. No grade 3 or grade 4 adverse event was observed, and main adverse events included fever (95.3%), pain (57.1%), fatigue (50.0%), and nausea/vomiting (42.8%). Conclusion: DEBIRI-TACE with CSM achieves high treatment response, acceptable survival benefits, and good toleration in unresectable CRLM treatment. [ABSTRACT FROM AUTHOR]

Background and objective: Decreasing X-ray tube voltage is an effective way to reduce radiation and contrast dose, especially in non-obese patients. The current study focuses on CTA in non-obese patients to evaluate image quality and feasibility of 80-kV acquisition protocols with varying iodine delivery rates (IDR) and contrast concentrations in routine clinical practice. Methods: A prospective observational study in patients ≥ 18 years and ≤ 90 kg referred for coronary or craniocervical CTA at 10 centers in China (ClinicalTrials.gov: NCT02840903). Patients were divided into four groups: a standard 100-kV protocol (370 mgI/ml, IDR 1.48 gI/s), and three 80-kV protocols (370 mgI/ml, IDR 1.2 gI/s; 300 mgI/ml, IDR 1.2 gI/s; 300 mgI/ml, IDR 0.96gI/s). The primary outcome was contrast opacification of target vascular segments. Secondary outcomes were image quality (contrast-to-noise ratio, signal-to-noise ratio, visual image quality, and diagnostic confidence assessment), radiation, and iodine dose. Results: From July 2016 to July 2017, 1213 patients were enrolled: 614 coronary and 599 craniocervical CTA. The mean contrast opacification was ≥ 300 HU for 80-kV 1.2 gI/s IDR scanned segments; IDR 0.96 gI/s led to lower opacification. Image quality and diagnostic confidence were fair to excellent (≥ 98% of images), despite lower contrast-to-noise ratios and signal-to-noise ratios in 80-kV images. Compared to the standard protocol, 80-kV protocols led to 44–52% radiation dose reductions (p < 0.001) and 19% iodine dose reductions (p < 0.001). Conclusion: Eighty-kilovolt 1.2 gI/s IDR protocols can be recommended for coronary and craniocervical CTA in non-obese patients, reducing radiation and iodine dose without compromising image quality. Key Points: • Using low-voltage scanning CTA protocols, in which tube voltage and iodine delivery rate are reduced proportionally (voltage: 80 kV, IDR: 1.2 gI/s), reduces radiation and contrast dose without compromising image quality in routine clinical practice. • Reducing iodine delivery rate beyond direct proportionality to tube voltage is not beneficial. [ABSTRACT FROM AUTHOR]

Drinking with others is seen as a necessary activity for business negotiations worldwide. However, employee alcohol use in business context is rarely investigated. This study focuses on employee business drinking (EBD), defined as employee drinking with clients for business matters. Based on role theory, the antecedents and consequences of EBD are examined using three-wave data obtained from 183 full-time Chinese employees. The results show that the leader business drinking norms and coworker business drinking norms have positive effects on EBD. Employees with high performance drinking motives and high alcohol tolerance are more likely to participate in EBD. Furthermore, EBD is positively related to leader-member exchange (LMX), team-member exchange (TMX), and client ties. These results show the drivers and potentially beneficial effects of EBD and provide important theoretical and practical implications. [ABSTRACT FROM AUTHOR]

Objective: To assess the overall diagnostic accuracy of different MR imaging sequences in the detection of the dysplastic nodule (DN). Methods: PubMed, Cochrane Library, and Web of Science were systematically searched. Study selection and data extraction were conducted by two authors independently. Quality assessment of diagnostic accuracy studies (QUADAS) 2 in RevMan software was used to score the included studies and assess their methodological quality. A random-effects model was used for statistical pooling by Meta-Disc. Subgroup analysis and sensitivity analysis were used to explore potential sources of heterogeneity. Results: Fourteen studies (335 DN lesions in total) were included in our meta-analysis. The area under the curve (AUC) of summary receiver operating characteristic (SROC) of T2WI was 0.87. Pooled sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) of DWI were 0.81 (95%CI, 0.73–0.87), 0.90 (95%CI, 0.86–0.93), 7.04 (95%CI, 4.49–11.04), and 0.24 (95%CI, 0.17–0.33) respectively. In the arterial phase, pooled sensitivity, specificity, PLR, and NLR were 0.89 (0.84–0.93), 0.75 (0.72–0.79), 3.72 (2.51–5.51), and 0.17 (0.12–0.25), respectively. Pooled sensitivity, specificity, PLR, and NLR of the delayed phase were 0.78 (0.72–0.83), 0.60 (0.55–0.65), 2.19 (1.55–3.10), and 0.36 (0.23–0.55) separately. Pooled sensitivity, specificity, PLR, and NLR of the hepatobiliary phase were 0.77 (0.71–0.82), 0.92 (0.89–0.94), 8.74 (5.91–12.92), and 0.24 (0.14–0.41) respectively. Pooled sensitivity, specificity, and PLR were higher on DWI and hepatobiliary phase in diagnosing LGDN than HGDN. Conclusion: MR sequences, particularly DWI, arterial phase, and hepatobiliary phase imaging demonstrate high diagnostic accuracy for DN. Key Points: • MRI has dramatically improved the detection and accurate diagnosis of DNs and their differentiation from hepatocellular carcinoma. • Overall diagnostic accuracy of different MRI sequences in the detection of DN has not been studied before. • Our meta-analysis demonstrates that MRI achieves a high diagnostic value for DN, especially when using DWI, arterial phase imaging, and hepatobiliary phase imaging. [ABSTRACT FROM AUTHOR]

The factors that influence graduate student creativity have drawn attention in higher education research. It is controversial whether leader–member exchange (LMX), here representing supervisor–student exchange relationship, can promote creativity. Previous studies on the LMX–creativity relationship have ignored the roles of negative psychological processes and personality differences. From the resource allocation perspective, we consider challenge stress and hindrance stress as the mediators and identify personal initiative (PI) as a moderator to examine the relationship between LMX and graduate student creativity. The results obtained from 576 Chinese samples confirm that LMX promotes graduate student creativity by reducing their hindrance stress; the interaction term between high PI and high LMX increases challenge stress. These findings support the importance of developing high quality supervisor–student exchange relationship for graduate students, adding their challenge stress, reducing their hindrance stress, and cultivating their PI so as to improve their creativity. [ABSTRACT FROM AUTHOR]

The continuing rise in cancer morbidity and mortality all over the world makes cancer the No. 2 cause of death in humans, posing a major public health challenge. Currently, surgery, radiotherapy, and chemotherapy are the three major approaches to treat cancer. However, the disadvantages of serious side effects, and poor therapeutic effect of the aforementioned methods in many clinical cases have become a burning question to be solved. DNA topoisomerases (Topos) are the key enzymes for DNA replication, transcription, recombination and repair, and have been regarded as target enzymes for some anticancer drugs, leading to the development of some successful anticancer drugs now in clinical use. Moreover, medicinal plants with numerous bioactive compounds are one of the most important sources for the discovery and development of anticancer drugs. In an active effort to search for Topo inhibitors from medicinal plants, affinity selection–ultrafiltration/high performance liquid chromatography–mass spectrometry (AS/UF–LC–MS) is among the most efficient techniques in term of sensitivity, throughput, and wide applicability. This review summarized the most recent advances in screening Topo inhibitors with AS/UF–LC–MS from medicinal plants over the past 15 years, with focus on structures, functions, the mechanisms of action of Topos and the procedures of the AS/UF–LC–MS technology, with an aim to provide comprehensive insights for new drug research and the discovery of more effective leading compounds against Topos. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study is to construct two nomograms for predicting the invasive extent of pulmonary adenocarcinoma and nodule growth in patients with pulmonary pure ground-glass nodules (pGGN). Method: Consecutive patients with pGGNs (n = 172) were retrospectively studied at one institution, formed the development cohort in predicting IPAs' nomogram. A separate cohort of patients with pGGNs (n = 116) from another institution was used for validation. For the predicting growth nomogram, the primary cohort of patients with pGGNs (n = 80) was from the former institution. We developed the nomogram for predicting IPA using binary logistic regression model, and a Cox multivariable model for the growth nomogram. We assessed nomogram model performance by calibration and discrimination (C-index). Results: The variables selected in binary logistic regression model (lesion size and shape) had a significant effect on identifying IPA from preinvasive lesion. The C-index of the development and validation cohort were 0.819 (95% CI 0.753–0.874) and 0.811 (95% CI 0.728–0.878), respectively. The risk variables (lesion size, blood vessel types) were selected in the multivariable Cox model. The C-index was 0.880 in the development cohort. Conclusion: Our nomograms are reliable prognostic methods that can predict the invasiveness of pulmonary adenocarcinomas and the growth of pure GGN in preoperative. [ABSTRACT FROM AUTHOR]

As a promising method in artificial intelligence, deep learning has been proven successful in several domains ranging from acoustics and images to natural language processing. With medical imaging becoming an important part of disease screening and diagnosis, deep learning-based approaches have emerged as powerful techniques in medical image areas. In this process, feature representations are learned directly and automatically from data, leading to remarkable breakthroughs in the medical field. Deep learning has been widely applied in medical imaging for improved image analysis. This paper reviews the major deep learning techniques in this time of rapid evolution and summarizes some of its key contributions and state-of-the-art outcomes. The topics include classification, detection, and segmentation tasks on medical image analysis with respect to pulmonary medical images, datasets, and benchmarks. A comprehensive overview of these methods implemented on various lung diseases consisting of pulmonary nodule diseases, pulmonary embolism, pneumonia, and interstitial lung disease is also provided. Lastly, the application of deep learning techniques to the medical image and an analysis of their future challenges and potential directions are discussed. [ABSTRACT FROM AUTHOR]

Objectives: Develop a CT-based radiomics model and combine it with frozen section (FS) and clinical data to distinguish invasive adenocarcinomas (IA) from preinvasive lesions/minimally invasive adenocarcinomas (PM).Methods: This multicenter study cohort of 623 lung adenocarcinomas was split into training (n = 331), testing (n = 143), and external validation dataset (n = 149). Random forest models were built using selected radiomics features, results from FS, lesion volume, clinical and semantic features, and combinations thereof. The area under the receiver operator characteristic curves (AUC) was used to evaluate model performances. The diagnosis accuracy, calibration, and decision curves of models were tested.Results: The radiomics-based model shows good predictive performance and diagnostic accuracy for distinguishing IA from PM, with AUCs of 0.89, 0.89, and 0.88, in the training, testing, and validation datasets, respectively, and with corresponding accuracies of 0.82, 0.79, and 0.85. Adding lesion volume and FS significantly increases the performance of the model with AUCs of 0.96, 0.97, and 0.96, and with accuracies of 0.91, 0.94, and 0.93 in the three datasets. There is no significant difference in AUC between the FS model enriched with radiomics and volume against an FS model enriched with volume alone, while the former has higher accuracy. The model combining all available information shows minor non-significant improvements in AUC and accuracy compared with an FS model enriched with radiomics and volume.Conclusions: Radiomics signatures are potential biomarkers for the risk of IA, especially in combination with FS, and could help guide surgical strategy for pulmonary nodules patients.Key Points: • A CT-based radiomics model may be a valuable tool for preoperative prediction of invasive adenocarcinoma for patients with pulmonary nodules. • Radiomics combined with frozen sections could help in guiding surgery strategy for patients with pulmonary nodules. [ABSTRACT FROM AUTHOR]

Increased attention has been paid to research on the outcomes of voice. However, the existing findings on the relationship between voice and employee performance are inconclusive. To address the insufficient understanding of the voice–employee performance relationship, this study proposed a model that specifies the relationships between two types of voice (i.e., promotive and prohibitive) and employee performance along with the moderating role of power distance orientation. The results of the analysis of a sample in China that comprised 80 leaders and 431 employees showed an inverted U-shaped relationship between promotive voice and employee performance and a positive linear relationship between prohibitive voice and employee performance. Power distance orientation was found to significantly moderate the nonlinear and linear relationships. Specifically, the inverted U-shaped relationship was more pronounced, while the positive linear relationship was weaker among employees with high power distance orientation. Theoretical and practical implications of the findings are discussed, along with the limitations of this study and future research directions. [ABSTRACT FROM AUTHOR]

Independent component analysis (ICA) on group-level voxel-based morphometry (VBM) produces the coefficient matrix and the component matrix. The former contains variability among multiple subjects for further statistical analysis, and the latter reveals spatial maps common for all subjects. ICA algorithms converge to local optimization points in practice and the mostly applied stability investigation approach examines the stability of the extracted components. We found that the practically stable components do not guarantee to produce the practically stable coefficients of ICA decomposition for the further statistical analysis. Consequently, we proposed a novel approach including two steps: (1), the stability index for the coefficient matrix and the stability index for the component matrix were examined, respectively; (2) the two indices were multiplied to analyze the stability of ICA decomposition. The proposed approach was used to study the sMRI data of Type II diabetes mellitus group and the healthy control group (HC). Group differences in VBM were found in the superior temporal gyrus. Besides, it was revealed that the VBMs of the region of the HC group were significantly correlated with Montreal Cognitive Assessment (MoCA) describing the level of cognitive disorder. In contrast to the widely applied approach to investigating the stability of the extracted components for ICA decomposition, we proposed to examine the stability of ICA decomposition by fusion the stability of both coefficient matrix and the component matrix. Therefore, the proposed approach can examine the stability of ICA decomposition sufficiently. [ABSTRACT FROM AUTHOR]

Drawing on a self-regulation perspective, we develop and test a theoretical model linking risk propensity to entrepreneurial intention through the mechanisms of entrepreneurial self-efficacy and regulatory focus. Using survey data collected from a sample of 210 employees and managers in China, the results indicated that entrepreneurial self-efficacy and promotion focus (but not prevention focus) are positively associated with entrepreneurial intention. Furthermore, these two self-regulatory mechanisms partially mediate the relationship between risk propensity and entrepreneurial intention. Implications for entrepreneurship research and practice are offered. [ABSTRACT FROM AUTHOR]

Rhamnus davurica Pall. (R. davurica) has been used as a traditional medicine for many years in China and abroad and shown a wide spectrum of biological activities. Previously, we reported the phytochemical fingerprinting profile of R. davurica, its distinct anti-proliferative activities against HT-29 and SGC-7901 cell lines, and the topoisomerase I (Top I) ligands based on bio-affinity ultrafiltration and HPLC-MS (UF-HPLC-MS). Nevertheless, among the 32 peaks detected in the fingerprinting profile, the common bioactive constituents responsible for the anti-inflammatory and anti-proliferative activities in the extracts remain elusive. To further explore the specific responsible components for their diversified activities and their potential action targets/mechanisms, the method based on bio-affinity UF-HPLC-MS using therapeutic targets like Top I and cyclooxygenase 2 (COX-2) was established to rapidly screen and identify the ligands binding to these known target enzymes. As a result, 12 components were revealed as potential Top I ligands along with 11 components as potential COX-2 ligands, where several components were revealed to possess both activities. Further validations of these bioactive components have also been conducted and confirmed their highlighted activities. This integrated method of UF-HPLC-MS exhibits high efficiency in rapidly screening for multi-target bioactive components responsible for multiple pharmacological effects from the complex natural products and could be very useful to explain the complex action mechanisms of herb medicines in a complex multi-component and multi-target mode at the molecular level.Schematic diagram of UF-HPLC-MS assay to screen for Top I and COX-2 ligands. The principle of the assay usually involves the following steps: incubation, ultrafiltration, and identification. [ABSTRACT FROM AUTHOR]

Improvisation is increasingly recognized as a critical strategy used by entrepreneurs for effectively dealing with unexpected events. Nevertheless, limited effort has been exerted in the investigation of the antecedents of entrepreneur improvisation. This study proposes and analyzes regulatory focus as an important antecedent of entrepreneur improvisation, and examines the moderating role of environmental turbulence in this relationship. Data are obtained from a two-wave survey of 99 entrepreneurs in the largest economic area in China. Empirical results indicate that promotion focus (but not prevention focus) is significantly related to entrepreneur improvisation. Furthermore, environmental turbulence significantly moderates the relationship between prevention focus and entrepreneur improvisation. These findings advance the understanding of entrepreneur improvisation and regulatory focus theory, and provide practical implications for entrepreneurs, investors and boards of directors. [ABSTRACT FROM AUTHOR]

A gas chromatography-mass spectrometry (GC-MS) method was developed for the identification and quantification of 2,8-dichlorodibenzo-p-dioxin (2,8-DCDD) in toothpaste and mouthwash consumer products. Liquid-liquid extraction and solid-phase extraction were used in the sample preparation. The limit of detection was 0.96 ng/g in toothpaste and 0.83 ng/g in mouthwash. The accuracy represented by relative errors was less than 12.5 %. The intra-day and inter-day precision, which are represented by the relative standard deviation values, were within 11.2 and 10.6 %, respectively. The method was successfully applied to analyze 2,8-DCDD in toothpaste and mouthwash products, as well as that from the photo-degradation of triclosan spiked in both sample matrix. [ABSTRACT FROM AUTHOR]

Objectives: To investigate whether DTI allows assessment of renal impairment and pathology in patients with chronic glomerulonephritis.Materials and Methods: Seventy-five patients and 20 healthy volunteers were enrolled in this study. Renal function and kidney biopsies were evaluated. For DTI, a respiratory-triggered coronal EPI sequence was performed (TR, 1400 ms; TE, 76 ms; diffusion direction, 6; NEX, 4; b values, 0 and 600 s/mm2; slices thickness, 6 mm, with no intersection gap). Renal ADC and FA values were calculated and compared between the groups. Correlations between ADC/FA and histopathology were evaluated.Results: ADC values decreased with increased stages. ADC differences in renal parenchyma at different disease stages were found, with the exception of the control group compared with stage 1 patients; similar results were obtained for FA. ADC values in the cortex and medulla in stage 1-3 patients were both statistically different, similar to the FA values. A significant negative correlation was found between the percentage of glomerulosclerosis and FA in the renal cortex (r =  -0.74), similar to the degree of tubulointerstitial fibrosis with FA in the medulla (r = -0.76).Conclusions: ADC and FA values are correlated with the degree of renal impairment, the percentage of glomerulosclerosis, and area of interstitial fibrosis.Key Points: • DTI can be used to assess renal function impairment in patients with chronic glomerulonephritis. • ADC and FA values were correlated with tubulointerstitial fibrosis and glomerulosclerosis. • Identification of renal impairment is helpful for timely treatment. • DTI can be used for non-invasive assessment of renal pathology. [ABSTRACT FROM AUTHOR]

The purpose of the study was to assess diagnostic performance of MSCT images in patients with parotid benign tumors and provide useful criteria for the characterization of their various pathological types preoperatively. Retrospectively analyzed clinical and imaging characteristics of 84 cases of pathologically confirmed primary parotid benign tumors. MSCT plain-scan and enhanced-scan were performed in all cases. After injection of 50 mL contrast material at a rate of 3.5 mL/s, spiral CT scans were obtained at arterial and venous phases with scanning delay of 30 s and 75 s, respectively. The attenuation change and enhancement patterns in the tumors were assessed. Quantitatively assess the increased CT number of the tumors in different enhanced-phases compared with the plain-scan and the ratio of increased CT number at venous phase scanning to that at arterial phase scanning also was calculated. In all of 84 cases, 40 cases were solitary pleomorphic adenomas, 29 cases were adenolyphomas, 6 cases were multiple tumors, 2 cases were bilateral, 15 cases were Basal cell tumor, and one of them had two small lesions. The diameter was 1–5 cm in most of cases, whose margin was smooth and clear, cystic changes in some cases. At two-phase scans, pleomorphic adenomas showed a pattern of slight enhancement and venous enhancement, adenolymphomas showed a pattern of strong enhancement at arterial phase scanning with a decrease at venous phase scanning, basal cell tumor showed a pattern of persistent strong enhancement with commonly significant cystic areas. The ratio of increased CT number was significant different between adenolymphomas and other pathological types. The evaluation of enhancement patterns at two-phase enhanced-scan MSCT is helpful in the differential diagnosis of parotid gland benign tumors. [ABSTRACT FROM AUTHOR]

Proton magnetic resonance spectroscopy (1H MRS) can provide specific biochemical information within breast lesions and the elevated composite choline concentration as a useful diagnostic tool has been used to distinguish malignant from benign breast lesions, early evaluate response to therapy and predict prognosis. However, several obstacles including poor spatial resolution, low signal-to-noise ratio (SNR), long acquisition time and the difficulty of “extra” lipid suppression may have a negative impact on the routine application of in vivo 1H MRS for human breast cancer. At present, optimization H MRS methodology for breast studies has been performed. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical diagnostic value of peripheral lung cancer using multi-slice CT (MSCT) perfusion imaging and the relationship with microvessel density (MVD). Methods: 38 patients with pulmonary masses proved by pathology including 25 cases of peripheral lung cancer and 13 cases of benign masses were studied prospectively with GE Lightspeed Qx/I plus 16-slice helical CT perfusion imaging, and 25 patients with lung cancer were comparative studied with its MVD calculated using LSAB. With the CT perfusion 2-body tumor software, the parameters of CT perfusion including blood value (BV), blood flow (BF), mean transit time (MTT) and permeability surface (PS) were analyzed. Results: The four parameter values in lung cancer were all higher than that in pulmonary benign masses, and there were significant differences among BV, MTT and PS ( P<0.05), especially in BV ( P<0.01). The MVD value of lung cancer was higher than that of pulmonary benign masses ( P<0.05), and the MVD of adenocarcinoma was higher than that of squamous cell carcinoma ( P<0.05). In 25 cases with lung cancer, there was positive correlation only between BV and MVD value ( r=0.852, P<0.01). Conclusion: It is helpful to diagnose the peripheral lung cancer with MSCT perfusion imaging and to differentiate from pulmonary benign masses, its bases are MVD pathologically. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical value of multi-slice helical CT angiography (MSCTA) in diagnosis of cerebral vascular diseases. Methods: 52 patients with cerebral vascular diseases were examined with GE Light Speed 4-slice and 16-slice helical CT. Pitch: 0.5–3, slice thickness: 0.625–1.25 mm, adult injection dosage: 90–100 mL, children injection dosage: 2 mL/kg, injection rate: 2.5–4.0 mL/s, delay time: 15–22 s. Intelligent track scan (Smart prep Rx) were adopted in parts of these cases. Three-dimensional cerebral vascular images were processed at ADW 3.1 and ADW 4.2 workstation. Results: MSCTA could clearly display spacious anatomic details of cerebral aneurysm, including its origin, size, neck width, and trend etc. MSCTA results of 19 cases were consistent with those of operations. The diameter of the smallest cerebral aneurysm shown in our research was about 3 mm. As a non-invasive examination, MSCTA could also be applied in post-operational evaluation of cerebral aneurysm by observing the location of silver clip and the distant vessels. Besides, MSCTA could be used to diagnose arteriovenous malformation and moyamoya disease. Of all the three-dimentional imaging methods, volume rendering (VR) is the best means to display the cerebral vascular diseases. Conclusion: As a non-invasive examination, MSCTA plays an important role in detection, pre-operational and post-operational evaluation of cerebral vascular diseases. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the clinical value of perfusion imaging in neoplasm in the brain and body with Multi-slice helical CT. Methods: Twenty-eight patients with neoplasm were subjected to perfusion imaging with multi-slice helical CT, including 22 patients with brain neoplasm and 6 patients with body neoplasm. At first, CT routine scan was preformed to localize central slices of neoplasm. Then perfusion imaging of 4 and identical slices in central slices of neoplasm was performed by using CT cine scan. Scanning images were transferred into ADW3.1 work-station to create and analyze perfusion images and parameters. Results: Perfusion parameters of cerebral neoplasm had a remarkable increase. But, CBF value of different cerebral neoplasms had partial overlap; CBV value was increased slightly; MTT value had no apparently clinical value; PS value was increased significantly, pituitary neoplasm>meningoma>cerebral glioma≈cerebral metastasis. PS value could reveal the characters of cerebral neoplasm and had apparently clinical value. Perfusion parameters of body neoplasms have a remarkable increase too. Body tumors were liable to be interfered by breath movement. Perfusion parameters were helpful to differentiation diagnosis of neoplasm in the brain and body. PS images of neoplasm in the brain and body were helpful to defining tumor outline and finding small tumor. Conclusion: MSCT perfusion imaging provided a precise and relative simple method to quantitatively estimate blood perfusion status in tumors in the brain and body. The technique can be easily implemented on clinical scanners. [ABSTRACT FROM AUTHOR]

The aim of our study was to investigate the value of Diffusion-weighted MR imaging (DWI) for evaluating differential diagnosis of pulmonary isolated lesions. Twenty-seven consecutive patients enrolled in this study, all of whom underwent single direction DWI examinations and received a histologic and clinical diagnosis. Diffusion factor B value was 300, 500, 800 s/mm2, respectively. DWI images of twenty cases could be satisfied to measurement and diagnosis and success rate was percent 74. Among these, lung tuberculoma 5 cases, harmatoma 3 cases, peripheral lung cancer 12 cases. The apparent diffusion coefficient (ADC) values of the lesions were measured. Statistical analyses were performed with the independent samples t test for comparing difference of ADC values between malignant nodules and benign nodules at different B value. DWI images of twenty cases could be satisfied and its success rate was percent 74. When B value was 300 s/mm2, ADC values of malignant nodules and benign nodules were 0.002192 ± 0.0006091 mm2/s, 0.002454 ± 0.0007892 mm2/s, respectively, and P = 0.442. When B value was 500 s/mm2, ADC value of malignant nodules and benign nodules were 0.002065 ± 0.0006769 mm2/s, 0.002871 ± 0.0007746 mm2/s, respectively, and P = 0.033. When B value was 800 s/mm2, ADC value of malignant nodules and benign nodules were 0.001646 ± 0.0004292 mm2/s, 0.002651 ± 0.0008041 mm2/s, respectively, and P = 0.009. There were the most different between malignant nodules and benign nodules at B value 800 and statistical significance. Lung DWI imaging is helpful to diagnosis and differential diagnosis between malignant and benign isolated nodules. The ADC value of benign lesions was statistically higher than that of malignant tumors. [ABSTRACT FROM AUTHOR]

The aim of our study was to investigate the value of dynamic contrast-enhanced MRI for evaluating differential diagnosis of pulmonary isolated lesions. Twenty-nine consecutive patients enrolled in this study, all of whom underwent DCE-MRI examinations and received a histologic and clinical diagnosis. Among these, lung tuberculoma 7 cases, harmatoma 3 cases, peripheral lung cancer 19 cases. DCE-MRI was acquired with 3D LAVA technique, total 18 phases were acquired, scanner time of per phase was 5–7″. After contrasting agent, twice successive scanning was acquired at 10″ and 50″. Then 1′ 30″, 2′, 2′30″, 3′, 3′30″, 4′, 5′, 6′, 7′, 8′, 9′, 10′, 11′, 12′ performed scanning. Region of interest was placed on the Maximum level in the tumors. According to Schaefer’s standard, four types of time signal intensity curve (TIC) were classified, which were A, B, C and D. Compared the dynamic parameters between benign and malignant nodules. Lung tuberculoma may display three curves: A type 1 case, ring-shaped enhancement 4 cases (periphery ring A type, central region D type), D type 2 cases. Harmatoma may display three curves: A type 1 case, C type 2 case. Peripheral lung cancer may display A type. Except 2 cases D type lung tuberculoma, we compared curve data of 8 cases benign nodules (including tuberculoma A type and periphery ring A type, harmatoma A type and C type) and lung cancer. SIEP%: benign nodules 0.7885 ± 0.5543, lung cancer 1.2623 ± 0.3059, P < 0.05; MER: benign nodules 1.0007 ± 0.4251, lung cancer 1.3694 ± 0.2740, P < 0.05; washout: P > 0.05. Lung MR imaging is helpful to diagnosis and differential diagnosis of isolated benign and malignant nodules. SIEP% and MER could offer valuable information. The evolution of global tuberculosis may be from A type to ring-shaped ennoblement to D type. It was easy to do right diagnosis to lung tuberculoma with ring-shaped ennoblement and D type. Peripheral lung cancer commonly displayed A type and needed identification with acute inflammation. So, it is important to anti-inflammatory follow-up for a few A type nodules. [ABSTRACT FROM AUTHOR]

The purpose of this study is preliminarily to discuss stomach perfusion imaging technique with Multi-slice CT and its clinical application value in stomach neoplasm. Fifteen patients with known stomach neoplasm performed perfusion imaging with 4 or 16 slice CT. Performing perfusion imaging in central slice of neoplasm, using CT cine scan, slice thick 10 mm/2i; with high pressure syringe, injecting quickly from right elbow-front vein, dosage 45–50 mL, injection rate 3.5–4.0 mL/s, scanning delay time 5 s, scanning total time 45 s. We performed perfusion CT post-processing using pancreatic mode of perfusion CT software. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) of gastric wall and tumor were computed for every case. BF, BV, MTT and PS of gastric tumor were 116.68 ± 90.09 mL/(min ·100 g), 9.57 ± 8.12 mL/100 g, 10.07 ± 7.74 s, 20.78 ± 19.68 mL/(min ·100 g), respectively. The P values for each CT perfusion parameters between gastric tumor and normal gastric wall were 0.001, 0.021, 0.155 and 0.031, respectively. Perfusion CT can provide hemodynamics of gastric tumors and play a key role in the diagnosis of gastric tumors. It’s clinical application prospect will be fully broad. [ABSTRACT FROM AUTHOR]

Objective: Large cell carcinoma of lung is a very rare tumor. The clinical characteristics and CT imaging feature of large cell carcinoma of lung were discussed in this article. Methods: Eight cases of large cell carcinoma of lung proven by post-operational pathology were retrospectively analyzed from 2000 to 2005 and the literature on it was reviewed. Results: All 8 cases were men. The average age of patients was 64.88 years. Seven cases were smokers. Six cases had obvious chest stuffy, short breath, thrill dry cough. Hereinto 3 cases had cardinal red blood sputum. CT images of large cell carcinoma of lung were represented as single and peripheral mass or nodule. The distribution of large cell carcinoma of lung was short of some rule. 75% focus had clear finitude. One case showed internal calcification and 2 cases showed cavity. They did not show internal fat density. Conclusion: Large cell carcinoma of lung is difficult to be diagnosed before operation. Its CT finding is nonspecific. [ABSTRACT FROM AUTHOR]

Objective: To evaluate three-dimensional bronchial artery imaging characters in central lung cancer and applied values with multi-slice spiral CT (MSCT) to provide theoretical evidence on blood supply and intervention therapy. Methods: Eighteen patients with central lung cancer underwent MSCT with real time helical thin-slice CT scanning. Three-dimensional bronchial artery reconstruction was done at the console work-station. The space anatomical characters of bronchial artery were observed through different rotations. Results: For 6 cases, the three-dimensional images of bronchial artery (33.33%) could exactly show the origins, the routes (lung inner segment and mediatism segment) and the diameters of bronchial arteries. Vision rate of bronchial arteries was the highest in pulmonary artery stricture and truncation groups, and the vessels’ diameter became larger apparently. These characters demonstrated blood supply of this kind of central lung cancer come from bronchial artery. Volume rendering images were the best ones among three-dimensional images. Conclusion: Three-dimensional imaging with MSCT in bronchial artery can reveal the anatomical characters of bronchial artery and provide theoretical evidence on blood supply and intervention therapy of central lung cancer. [ABSTRACT FROM AUTHOR]

Tracheal Bronchus (TB) is a rare congenital anomaly characterized by the presence of an abnormal bronchus originating from the trachea or main bronchi and directed toward the upper lobe. The airflow pattern in tracheobronchial trees of TB subjects is critical, but has not been systemically studied. This study proposes to simulate the airflow using CT image based models and the computational fluid dynamics (CFD) method. Six TB subjects and three health controls (HC) are included. After the geometric model of tracheobronchial tree is extracted from CT images, the spatial distribution of velocity, wall pressure, wall shear stress (WSS) is obtained through CFD simulation, and the lobar distribution of air, flow pattern and global pressure drop are investigated. Compared with HC subjects, the main bronchus angle of TB subjects and the variation of volume are large, while the cross-sectional growth rate is small. High airflow velocity, wall pressure, and WSS are observed locally at the tracheal bronchus, but the global patterns of these measures are still similar to those of HC. The ratio of airflow into the tracheal bronchus accounts for 6.6-15.6% of the inhaled airflow, decreasing the ratio to the right upper lobe from 15.7-21.4% (HC) to 4.9-13.6%. The air into tracheal bronchus originates from the right dorsal near-wall region of the trachea. Tracheal bronchus does not change the global pressure drop which is dependent on multiple variables. Though the tracheobronchial trees of TB subjects present individualized features, several commonalities on the structural and airflow characteristics can be revealed. The observed local alternations might provide new insight into the reason of recurrent local infections, cough and acute respiratory distress related to TB. [ABSTRACT FROM AUTHOR]