Publications by authors named "Sheng Xie"

139 Publications

A low noise transimpedance amplifier for optical receiver.

Rev Sci Instrum 2021 Mar;92(3):034706

Tianjin Key Laboratory of Imaging and Sensing Microelectronic Technology, School of Microelectronics, Tianjin University, Tianjin 300072, China.

In this paper, a regulated cascode (RGC) structure and a shunt-feedback transimpedance amplifier are cascaded. By analyzing the average input-referred noise current, this paper used the method of adjusting the metal-oxide-semiconductor size and increasing the transimpedance gain to optimize the circuit noise characteristics without introducing redundant structures and noise sources. The measured results demonstrated that when the photodetector capacitance is 300 pF and the supply voltage is 1.8 V, the fabricated transimpedance amplifier has a transimpedance gain of 59.5 dBΩ and a -3 dB bandwidth of 4 GHz. Simultaneously, the average input-referred noise current spectral density is less than 7 pA/√Hz, and the data rate is as high as 5 Gb/s. The circuit takes advantage of the traditional shunt-feedback transimpedance amplifier and introduces a RGC structure between it and the input terminal as a current buffer structure. A π-type matching network was formed by adding an inductor between the shunt-feedback amplifier and the introduced RGC. All these structures can effectively improve the gain-bandwidth product of the designed amplifier.
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http://dx.doi.org/10.1063/5.0031658DOI Listing
March 2021

MicroRNA-4429 suppresses proliferation of prostate cancer cells by targeting distal-less homeobox 1 and inactivating the Wnt/β-catenin pathway.

BMC Urol 2021 Mar 19;21(1):40. Epub 2021 Mar 19.

Department of Andrology, Renmin Hospital, Hubei University of Medicine, No. 39 Chaoyang Middle Road, Maojian District, Shiyan, 442000, Hubei, People's Republic of China.

Background: Emerging evidence suggests that microRNAs (miRNAs) play multiple roles in human cancers through regulating mRNAs and distinct pathways. This paper focused on the functions of miR-4429 in prostate cancer (PCa) progression and the molecules involved.

Methods: Expression of miR-4429 in PCa tissues and cells was determined. Upregulation of miR-4429 was introduced in PCa cells to examine its role in the malignant behaviors of cells. The putative target mRNA of miR-4429 involved in PCa progression was predicted from a bioinformatic system and validated through luciferase assays. Overexpression of distal-less homeobox 1 (DLX1) was further induced in cells to validate its implication in miR-4429-mediated events. The activity of Wnt/β-catenin pathway was determined.

Results: miR-4429 was poorly expressed in PCa tissues and cells. Artificial upregulation of miR-4429 significantly reduced proliferation, growth, invasion, migration and resistance to death of cancer cells and inactivated the Wnt/β-catenin pathway. DLX1 mRNA was found as a target of miR-4429. Upregulation of DLX1 restored the malignant behaviors of PCa cells which were initially suppressed by miR-4429, and it activated the Wnt/β-catenin pathway.

Conclusion: Our study highlights that miR-4429 inhibits the growth of PCa cells by down-regulating DLX1 and inactivating the Wnt/β-catenin pathway. This finding may offer novel insights into PCa treatment.
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http://dx.doi.org/10.1186/s12894-021-00810-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7980590PMC
March 2021

Radiomics study on pulmonary infarction mimicking community-acquired pneumonia.

Clin Respir J 2021 Mar 8. Epub 2021 Mar 8.

Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China.

Introduction And Objectives: Pulmonary infarction (PI) shares similar symptoms and imaging presentations with community-acquired pneumonia (CAP), which might delay diagnosis and lead to devastating consequences. Noncontrast computed tomography (CT) is the first-line examination for the patients with the respiratory symptoms. This study aimed to investigate a radiomics method to differentiate PI from CAP using noncontrast-enhanced CT.

Methods: Noncontrast-enhanced CT images of 54 patients with PI and 64 patients with CAP were retrospectively selected. All patients were confirmed using computed tomography pulmonary angiography (CTPA). A radiomics model was built with 18 texture features that showed significant differences between PI and CAP patients. For comparison, a clinical model using clinical biomarkers and an integrated model combining the radiomics and clinical biomarkers were also generated. An experienced radiologist performed diagnoses using the noncontrast-enhanced CT images. The parameters of the models were generated using a training dataset of 61 patients, whereas the performance of the models was evaluated using receiver operating characteristic (ROC) analysis and Harrell's concordance index (C-index) applied to a separate validation dataset of 57 patients.

Results: The integrated model achieved the best performance (C-index 0.760, sensitivity 0.703, specificity 0.867, positive predictive value [PPV] 0.826, and negative predictive value [NPV] 0.765). The radiomics model was better than both the clinical model and the radiologist's interpretations (C-index 0.721, 0.707, 0.665, respectively; sensitivity 0.667, 0.630, 0.593; specificity 0.800, 0.785, 0.733; PPV 0.750, 0.739, 0.667; and NPV 0.727, 0.706, 0.667).

Conclusions: Radiomics features generated from noncontrast-enhanced CT images allow PI to be differentiated from CAP with considerable accuracy. The radiomics-based method could provide useful information in clinical practice.
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http://dx.doi.org/10.1111/crj.13341DOI Listing
March 2021

Expression of CEACAM1 and CD105 in Renal Cell Carcinoma and Its Correlation with Microvessel Density.

Crit Rev Eukaryot Gene Expr 2021 ;31(1):1-9

Department of Andrology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China.

We investigated expression of carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and endoglin (CD105) in renal cell carcinoma (RCC), and its potential role in predicting tumor growth and progression. A total of 47 RCC specimens and 15 adjacent normal kidney tissues were obtained. Expression of CEACAM1 and CD105 was assessed by immunohistochemistry. Microvessel density (MVD) was counted under the microscope by labeling the endothelial cells with biomarker CD34. The positivity of CEACAM1 expression in RCC (42.6%) was significantly lower than that in the normal kidney (73.%, P = 0.038). In contrast, the positivity of CD105 expression was significantly higher in RCC (78.7%) compared to that in the normal kidney (46.7%, P = 0.017). The expression level of CD105 in 47 RCC patients was significantly associated with the clinical stages of RCC (P < 0.05) but not with gender, age, tumor size, or histologic grade. Average MVD in RCC (78.05 ± 16.57) was significantly higher than that in normal tissue (43.62 ± 12.37, P < 0.05), and was significantly higher in RCC patients with advanced histologic grades (P < 0.05) or clinical stages (P < 0.01). In addition, MVD was significantly correlated with CD105 but negatively correlated with CEACAM1. Our findings suggest that down-regulation of CEACAM1 may promote angiogenesis in RCC, and that up-regulation of CD105 may promote RCC progress. MVD may be an indicator of RCC malignancy.
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http://dx.doi.org/10.1615/CritRevEukaryotGeneExpr.2020037168DOI Listing
January 2021

Uncontrollable Hemoptysis Due to Pseudoangiosarcomatous Carcinoma of the Lung.

Am J Respir Crit Care Med 2021 Feb 24. Epub 2021 Feb 24.

China-Japan Friendship Hospital, 36635, Radiology, Beijing, China.

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http://dx.doi.org/10.1164/rccm.202004-1307IMDOI Listing
February 2021

The utility of simultaneous CT-guided localization for multiple pulmonary nodules using microcoil before video-assisted thoracic surgery.

BMC Pulm Med 2021 Jan 25;21(1):39. Epub 2021 Jan 25.

Department of Radiology, China-Japan Friendship Hospital, No. 2 Yinghua East Street, Chaoyang District, Beijing, 100029, China.

Background: To evaluate the feasibility and safety of microcoil in simultaneous localization for multiple pulmonary nodules before video-assisted thoracic surgery (VATS).

Methods: Twenty-eight consecutive patients (26 two-nodule, 2 three-nodule; 58 nodules in total; Group A) underwent simultaneous CT-guided localization of multiple pulmonary nodules before VATS using microcoil. Successful targeting, localization, and VATS were defined as implantation of microcoil at the target site on CT image which was obtained immediately after the marking procedure, visualization of nodule location, and complete resection of the target nodule with adequate margin, respectively. Meanwhile, the clinical characteristics, localization procedure-related variables of the nodules and procedure-related complications in group A were also assessed and compared with those in a control group (221 single-localization procedures in 221 patients; Group B).

Results: Similar rates of successful targeting, localization and VATS were observed in group A and B (96.6% vs. 98.2%; 91.4% vs. 91.0%; 100% vs. 99.1%). Although the rate of overall complications (including localized pneumothorax and intrapulmonary hemorrhage) was a bit higher in group A than that in group B (32.8% vs. 30.8%, p = 0.771), only minor complications were observed in the subjects of the two groups with no need for further treatment. In addition, the duration of simultaneous localization procedures was significantly longer than that of single localization (24 ± 7.5 vs.13 ± 6 min, p < 0.001).

Conclusions: CT-guided simultaneous microcoil localization for multiple pulmonary nodules before VATS was clinically feasible and safe with acceptable increase in the procedure time. Compared with localization for a single pulmonary nodule, simultaneous microcoil localizations for multiple nodules were prone to pneumothorax and hemorrhage. However, no statistically significant differences were observed between the two groups.
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http://dx.doi.org/10.1186/s12890-021-01393-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831238PMC
January 2021

Associations between gastro-oesophageal reflux disease and a range of diseases: an umbrella review of systematic reviews and meta-analyses.

BMJ Open 2020 12 30;10(12):e038450. Epub 2020 Dec 30.

Department of Administration, The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning, Guangxi, China

Objective: Numerous meta-analyses have revealed the association between gastro-oesophageal reflux disease (GORD) and a range of diseases; however, the certainty of the evidence remains unclear. This study aimed to summarise and assess the certainty of evidence derived from meta-analyses.

Methods: Embase, PubMed, Web of Science, Cochrane Databases of Systematic Reviews, CNKI and Wangfang databases from their inception to 22 February 2020 were queried for systematic reviews and meta-analyses on the association between GORD and various diseases. The methodological quality of the included studies was assessed using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), and evidence certainty was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Statistical analysis was conducted using Stata V.15.

Results: Ten publications with associations between GORD and different types of diseases were included. There was high heterogeneity (I >75%) among seven independent meta-analyses. Evidence for publication bias in two independent meta-analyses was also observed. According to the AMSTAR 2 approach, the methodological quality was high for 20% of meta-analyses, moderate for 10%, low for 40% and critically low for 30%. Based on GRADE approach, the certainty of evidence was high for the association between GORD and higher risk of chronic obstructive pulmonary disease (COPD) exacerbation (OR 5.37; 95% CI 2.71 to 10.64) and higher prevalence of oesophageal adenocarcinoma (OR 4.57; 95% CI 3.89 to 5.36), and it was moderate for the association between GORD and higher chronic rhinosinusitis prevalence (OR 2.16; 95% CI 1.37 to 3.48).

Conclusion: The association between GORD and a range of diseases was extensively studied, and our findings revealed a high certainty of evidence of the association between GORD and an increased risk of COPD exacerbation as well as increased prevalence of oesophageal adenocarcinoma. Further investigations using systematic reviews and meta-analyses of high methodological quality that include prospective large cohort studies and adjusted confounders are warranted.

Prospero Registration Number: CRD42019122264.
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http://dx.doi.org/10.1136/bmjopen-2020-038450DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7780720PMC
December 2020

[Application of the Green Model to lifestyle intervention in male sterility patients].

Zhonghua Nan Ke Xue 2020 May;26(5):441-445

Department of Andrology, Shiyan People's Hospital / People's Hospital Affiliated to Hubei Medical College, Shiyan, Hubei 442000, China.

Objective: To evaluate the application of the Green Model to lifestyle intervention in male infertility patients.

Methods: A total of 120 male infertility patients treated from October 2018 to January 2019 were equally randomized into a control and an observation group, the former given conventional nursing and the latter Green Model intervention in addition. Comparisons were made between the two groups of patients in their satisfaction with nursing intervention, scores on lifestyle knowledge, beliefs and behaviors, and compliance with the healthy lifestyle.

Results: The patients in the observation group showed a dramatically higher satisfaction with the nursing intervention than the controls (96.67% vs 75.00%, P < 0.01) as well as higher scores on lifestyle knowledge (8.92 ± 1.08 vs 5.89 ± 1.99, P < 0.05), beliefs (8.78 ± 0.68 vs 5.98 ± 1.50, P < 0.05) and behaviors (19.32 ± 1.12 vs 13.88 ± 2.11, P < 0.05) and their compliance with the healthy lifestyle (61.67% vs 38.33, P < 0.05).

Conclusions: Green Model intervention can help male infertility patients to obtain correct lifestyle cognition, beliefs and behaviors, promote their compliance with the healthy lifestyle and improve their satisfaction with nursing intervention.
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May 2020

LINC00680 Promotes the Progression of Non-Small Cell Lung Cancer and Functions as a Sponge of miR-410-3p to Enhance HMGB1 Expression.

Onco Targets Ther 2020 18;13:8183-8196. Epub 2020 Aug 18.

Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, People's Republic of China.

Purpose: LINC00680 was reported to be involved in various cancers through multiple mechanisms. Therefore, we intended to investigate its role in the progression of non-small cell lung cancer (NSCLC).

Materials And Methods: Firstly, quantitative real-time polymerase chain reaction (qRT-PCR) was used to test LINC00680 in NSCLC tissue and cell lines. Subsequently, A549 and H1299 cells were transfected with LINC00680 overexpressing plasmids and their proliferation and colony formation and apoptosis was tested by Transwell assay and flow cytometry. In addition, xenograft tumor experiments in nude mice also affirmed. Meanwhile, we predicted that miR-410-3p, LINC00680 and high-mobility group protein box 1(HMGB1) relationship by Starbase, dual-luciferase reporter and RIP assay. Finally, the carcinogenic effects of LINC00680 were reversed by ethyl pyruvate (EP), a specific inhibitor of HMGB1.

Results: LINC00680 was upregulated in NSCLC and was closely related to the malignancy and poor prognosis of NSCLC patients. LINC00680 promoted proliferation and colony formation and inhibited apoptosis of A549 and H1299 cells. In addition, overexpressing LINC00680 accelerated the growth of NSCLC cells in xenograft tumor experiments in nude mice also affirmed. Meanwhile, high-mobility group protein box 1(HMGB1) was astoundingly amplified in NSCLC and was negatively regulated by miR-410-3p. Further, HMGB1 acted as a downstream target of miR-410-3p, upregulating miR-410-3p to attenuate HMGB1, while LINC00680 strengthened the expression of HMGB1 in A549 and H1299 cells.

Discussion: Thus, these results indicated that LINC00680 was cancerogenic in NSCLC by upregulating HMGB1 via sponging miR-410-3p.
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http://dx.doi.org/10.2147/OTT.S259232DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7455755PMC
August 2020

Assessment of Clinical Stage IA Lung Adenocarcinoma with pN1/N2 Metastasis Using CT Quantitative Texture Analysis.

Cancer Manag Res 2020 28;12:6421-6430. Epub 2020 Jul 28.

Department of Radiology, China-Japan Friendship Hospital, Beijing 100029, People's Republic of China.

Objective: To explore the application of texture analysis basing on computed tomography (CT) images in predicting lymph-node metastasis in patients with clinical stage IA lung adenocarcinoma.

Methods: In total, 256 patients with clinical stage IA lung adenocarcinoma who had underwentgone preoperative CT examinations were enrolled. A total of 25 texture features using MaZda (version 4.6) software and conventional radiological features were extracted from raw CT data sets. Based on surgical results, patients were stratified into lymph node metastasis-positive and -negative groups. Independent-sample -tests and Mann-Whitney tests were used to compare continuous variables between the groups. Continuity-correction and χ tests were used for categorical variable comparison. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of lymph-node metastasis.

Results: In total, 256 clinical stage IA lung adenocarcinoma cases were proved by pathology: 39 (15.23%) cases with lymph-node metastasis (14 N1a, seven N1b, six N2a1, ten N2a2, and two N2b) and 217 (84.77%) cases without lymph-node metastasis. Univariate and multivariate logistic regression analyses demonstrated that total volume (OR 3.777, =0.015), average CT value of whole tumor (OR 16.271, <0.001), three texture parameters (mean OR 8.473, <0.001; skewness OR 6.393, =0.001; and entropy OR 0.343, =0.049) were independent factors associated with lymph-node status. As such, early-stage lung adenocarcinoma with higher total volume (>4.05 cm), average CT value of whole tumor (>-70 HU), mean (>133.79), entropy (>1.98), and lower skewness (≤0.02) pointed to positive lymph-node metastasis.

Conclusion: Texture parameters were independent factors associated with lymph-node status in clinical stage IA lung adenocarcinoma.
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http://dx.doi.org/10.2147/CMAR.S251598DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7396813PMC
July 2020

Nonenzyme Cascaded Amplification Biosensor Based on Effective Aggregation Luminescence Caused by Disintegration of Silver Nanoparticles.

ACS Sens 2020 07 7;5(7):1912-1920. Epub 2020 Jul 7.

Department of Chemistry, Department of Chemical and Biological Engineering, Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute for Advanced Study, Institute of Molecular Functional Materials, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.

Sensitive and portable quantification of biomarkers has particular significance in the monitoring and treatment of clinical diseases. Conventional immunoassays were accustomed to introducing or incorporating enzymes for signal amplification, which commonly suffered from poor stability and inferior tolerance. Herein, we constructed a novel nonenzyme amplification methodology based on fluorogenic Ag-tetrazolate aggregation coupled with silver corrosion sensitization for biomarker determination. A significant cascade enhancement strategy was achieved by the valid aggregation luminescence caused by the potent disintegration of silver nanoparticles. Furthermore, efficient magnetic separation was also combined and performed for the rapidity and simplicity of operation. As the target, the detection limit of prostate-specific antigen was 15.66 pg/mL in our designed biosensor. Besides, a good linear relationship was obtained. The designed biosensor demonstrated good specificity and was successfully applied to clinical serum sample detection.
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http://dx.doi.org/10.1021/acssensors.9b02355DOI Listing
July 2020

The morphological characteristics of hippocampus and thalamus in mesial temporal lobe epilepsy.

BMC Neurol 2020 Jun 8;20(1):235. Epub 2020 Jun 8.

Department of Neurology, China-Japan Friendship Hospital, Beijing, 100029, China.

Background: Mesial temporal lobe epilepsy (MTLE) is the most common form of focal epilepsy, which is frequently characterized by hippocampal sclerosis (HS). Accumulating studies have suggested widespread cortico-cortical connections related to MTLE. The role of subcortical structures involved in general epilepsy has been extensively investigated, but it is still limited in MTLE. Our purpose was to determine the specific morphological correlation between sclerotic hippocampal and thalamic sub-regions, using quantitative analysis, in MTLE.

Methods: In this study, 23 MTLE patients with unilateral hippocampal sclerosis and 24 healthy controls were examined with three-dimensional T1 MRI. Volume quantitative analysis in the hippocampus and thalamus was conducted and group-related volumetric difference was assessed. Moreover, vertex analysis was further performed using automated software to delineate detailed morphological patterns of the hippocampus and thalamus. The correlation was used to examine whether there is a relationship between volume changes of two subcortical structures and clinical characteristics.

Results: The patients had a significant volume decrease in the sclerotic hippocampus (p < 0.001). Compared to controls, obvious atrophic patterns were observed in the bilateral hippocampus in MTLE (p < 0.05). Only small patches of shrinkage were noted in the bilateral thalamus (p < 0.05). Moreover, the volume change of the hippocampus had a significant positive correlation with that of the thalamus (P < 0.001). Intriguingly, volume changes of the hippocampus and thalamus were correlated with the duration of epilepsy (hippocampus: P = 0.024; thalamus: P = 0.022). However, only volume changes of thalamus possibly differentiated between two prognostic groups in patients (P = 0.026).

Conclusions: We demonstrated the morphological characteristics of the hippocampus and thalamus in MTLE, providing new insights into the interrelated mechanisms between the hippocampus and thalamus, which have potential clinical significance for refining neuromodulated targets.
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http://dx.doi.org/10.1186/s12883-020-01817-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7282186PMC
June 2020

CT-guided microcoil localization for pulmonary nodules before VATS: a retrospective evaluation of risk factors for pleural marking failure.

Eur Radiol 2020 Oct 26;30(10):5674-5683. Epub 2020 May 26.

Department of Radiology, China-Japan Friendship Hospital, No.2 Yinghua East Street, Chaoyang District, Beijing, 100029, China.

Objectives: To summarize the experiences of CT-guided microcoil localization before video-assisted thoracoscopic surgery (VATS) and to investigate the risk factors associated with pleural marking failure.

Methods: Totally, 249 consecutive patients with 279 pulmonary nodules who underwent CT-guided microcoil localization prior to VATS were enrolled in this study. According to intraoperative observation, all the nodules were divided into two groups. The clinical characteristics and microcoil localization procedure-related variables of the nodules were analyzed by univariate analysis and multivariate logistic regression analysis to screen the independent factors associated with procedure results.

Results: Among the 279 nodules, 28 failed to observe the proximal end of the microcoil deployed on visceral pleura during VATS. The logistic regression revealed that needle-pleura angle (≤ 30°: OR = 39.022, p = 0.003), pleura-microcoil distance (≤ 10 mm: OR = 87.054, p < 0.001; 10~20 mm: OR = 10.088, p = 0.010), and presence of pleural indentation (OR = 21.623, p < 0.001) were independent risk factors for pleural marking failure.

Conclusions: CT-guided microcoil localization for pulmonary nodules is a safe and effective procedure. Small needle-pleura angle (≤ 30°), pleura-microcoil distance (≤ 20 mm), and the presence of pleural indentation during the procedure are significant risk factors contributing to microcoil pleura marking failure.

Key Points: • CT-guided microcoil localization for pulmonary nodules was a safe and effective procedure. • CT-guided microcoil localization for pulmonary nodules yielded low complication rates. • Small needle-pleura angle, short pleura-microcoil distance, and the presence of pleural indentation were contributing to pleura marking failure.
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http://dx.doi.org/10.1007/s00330-020-06954-yDOI Listing
October 2020

Directional axonal regrowth induced by an aligned fibrin nanofiber hydrogel contributes to improved motor function recovery in canine L2 spinal cord injury.

J Mater Sci Mater Med 2020 Apr 21;31(5):40. Epub 2020 Apr 21.

State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China.

Spinal cord injuries (SCI) normally disrupt the long axonal tracts of the spinal cord and cause permanent neurological deficits, for which there is currently a lack of effective therapeutic methods. Biomaterial-based regenerative medicine is a pivotal strategy to induce axonal regeneration through delivery of biophysical and/or biochemical regulatory cues by biomaterials. We previously fabricated a hierarchically aligned fibrin hydrogel (AFG) that could promote neurogenic differentiation of stem cells in vitro and has been successfully applied for peripheral nerve and spinal cord regeneration in rats. In this study, AFG was used to repair a canine lumbar segment 2 hemisection spinal cord injury, and the consistency of histological, imageological and behavioral results was compared. AFG was used to construct an aligned fiber bridge that supported cell adhesion in vitro and rapidly facilitated tissue invasion along the long axis of fibers in vivo, Moreover, in vivo results demonstrated regrowth of axons in an oriented pattern connecting the rostral and caudal stumps. Consistent results were confirmed by diffusion tensor imaging, which allowed successful tracing of reconnected nerve fibers across the defect. As a result, directional axonal regrowth contributed to significantly improved recovery of motor functional behavior of SCI canines with AFG implantation. Our results suggest that AFG has great promise for rapidly directing axonal regrowth for nerve regeneration.
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http://dx.doi.org/10.1007/s10856-020-06375-9DOI Listing
April 2020

Bearing-Only Formation Control With Prespecified Convergence Time.

IEEE Trans Cybern 2020 Apr 8. Epub 2020 Apr 8.

This article considers the bearing-only formation control problem, where the control of each agent only relies on relative bearings of their neighbors. A new control law is proposed to achieve target formations in finite time. Different from the existing results, the control law is based on a time-varying scaling gain. Hence, the convergence time can be arbitrarily chosen by users, and the derivative of the control input is continuous. Furthermore, sufficient conditions are given to guarantee almost global convergence and interagent collision avoidance. Then, a leader-follower control structure is proposed to achieve global convergence. By exploring the properties of the bearing Laplacian matrix, the collision avoidance and smooth control input are preserved. A multirobot hardware platform is designed to validate the theoretical results. Both simulation and experimental results demonstrate the effectiveness of our design.
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http://dx.doi.org/10.1109/TCYB.2020.2980963DOI Listing
April 2020

Electrophilic Azides for Materials Synthesis and Chemical Biology.

Acc Chem Res 2020 04 24;53(4):937-948. Epub 2020 Mar 24.

Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, Massachusetts 01854, United States.

Organic azides are involved in a variety of useful transformations, including nitrene chemistry, reactions with nucleophiles and electrophiles, and cycloadditions. The 1,3-dipolar cycloadditions of azides constitute a major class of highly reliable and versatile reactions, as shown by the development and rapid adoption of click chemistry and bioorthogonal chemistry. Metal-catalyzed azide-alkyne cycloaddition (Cu/RuAAC), the prototypical click reaction, has found wide utility in pharmaceutical, biomedical, and materials sciences. The strain-promoted, or distortion-accelerated, azide-alkyne cycloaddition eliminates the need for a metal catalyst.In the azide-mediated 1,3-dipolar cycloaddition reactions, azides are ambiphilic, i.e., HOMO-LUMO-controlled dipoles where both the HOMO and LUMO interact strongly with the dipolarophile. Azide-alkyne cycloaddition proceeds primarily through the HOMO-LUMO interaction, and electron-deficient dipolarophiles react more readily. The inverse-electron-demand reaction, involving the LUMO-HOMO interaction, is less common because of the low stability of electron-deficient azides such as acyl, sulfonyl, and phosphoryl azides. Nevertheless, there have been reports since the 1960s showing enhanced reaction kinetics between electron-poor azides and electron-rich dipolarophiles. Our laboratory has developed the use of perfluoroaryl azides (PFAAs), a class of stable electron-deficient azides, as nitrene precursors and for reactions with nucleophiles and electron-rich dipolarophiles. Perfluorination on the aryl ring also facilitates the synthesis of PFAAs and quantitative analysis of the products by F NMR spectroscopy.In this Account, we summarize key reactions involving electrophilic azides and applications of these reactions in materials synthesis and chemical biology. These electron-deficient azides exhibit unique reactivity toward nucleophiles and electron-rich or strained dipolarophiles, in some cases leading to new transformations that do not require any catalysts or products that are impossible to obtain from the nonelectrophilic azides. We highlight work from our laboratories on reactions of PFAAs with enamines, enolates, thioacids, and phosphines. In the reactions of PFAAs with enamines or enolates, the triazole or triazoline cycloaddition products undergo further rearrangement to give amidines or amides as the final products at rates of up to 10 times faster than their non-fluorinated anlogues. Computational investigations by the distortion/interaction activation strain model reveal that perfluorination lowers the LUMO of the aryl azide as well as the overall activation energy of the reaction by decreasing the distortion energies of the reactants to reach the transition states. The PFAA-enamine reaction can be carried out in a one-pot fashion using readily available starting materials of aldehyde and amine, making the reaction especially attractive, for example, in the functionalization of nanomaterials and derivatization of antibiotics for the preparation of theranostic nanodrugs. Similar fast kinetics was also observed for the PPAA-mediated Staudinger reaction, which proceeds at 10 times higher rate than the classic Staudinger ligation, giving stable phosphoimines in high yields. The reaction is biorthogonal, allowing cell-surface labeling with minimal background noise.
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http://dx.doi.org/10.1021/acs.accounts.0c00046DOI Listing
April 2020

MRI-determined liver fat correlates with risk of metabolic syndrome in patients with nonalcoholic fatty liver disease.

Eur J Gastroenterol Hepatol 2020 06;32(6):754-761

Department of Gastroenterology, China-Japan Friendship Hospital, Beijing, China.

Background And Aim: Little is known about that the relationship between hepatic fat content (HFC) and metabolic syndrome (MetS). We aimed to determine whether HFC correlated with MetS in patients with nonalcoholic fatty liver disease (NAFLD).

Methods: HFC was measured by MRI-determined proton density fat fraction (MRI-PDFF) for 131 suspected NAFLD subjects. Patients with NAFLD defined as MRI-PDFF ≥5% were stratified into two groups based on whether they were above or below the median MRI-PDFF value; the MRI-PDFF value for the control group was <5%. The primary outcome was the presence of MetS. Logistic regression models were used to obtain the associations between the severity of liver fat and MetS, and the corresponding odds ratios (ORs) and 95% confidence intervals (CIs) were recorded.

Results: Compared to NAFLD patients with low-HFC (n = 48) and the control group (n = 35), NAFLD patients with high-HFC (n = 48) had significantly greater prevalence of central obesity, hypertension, hyperglycemia, and hypertriglyceridemia (all P < 0.05). NAFLD patients with high-HFC had a higher prevalence of MetS than NAFLD patients with low-HFC (79.2% vs. 56.2%, P < 0.05). The multivariate-adjusted OR for the prevalence of MetS comparing NAFLD patient with low-HFC and high-HFC to the control group were 4.56 (95% CI: 0.54-38.79, P = 0.165) and 22.91 (95% CI: 1.80-292.21, P = 0.016), respectively (Ptrend = 0.014).

Conclusion: Increased hepatic fat quantitatively measured by MRI-PDFF had a significant dose-relationship with the presence of MetS, and the amount of liver fat may affect cardiovascular risk.
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http://dx.doi.org/10.1097/MEG.0000000000001688DOI Listing
June 2020

Evaluation of acute pulmonary embolism and clot burden on CTPA with deep learning.

Eur Radiol 2020 Jun 16;30(6):3567-3575. Epub 2020 Feb 16.

Department of Radiology, China-Japan Friendship Hospital, 2 Yinghua Dong Street, Hepingli, Chao Yang District, Beijing, 100029, China.

Objectives: To take advantage of the deep learning algorithms to detect and calculate clot burden of acute pulmonary embolism (APE) on computed tomographic pulmonary angiography (CTPA).

Materials And Methods: The training set in this retrospective study consisted of 590 patients (460 with APE and 130 without APE) who underwent CTPA. A fully deep learning convolutional neural network (DL-CNN), called U-Net, was trained for the segmentation of clot. Additionally, an in-house validation set consisted of 288 patients (186 with APE and 102 without APE). In this study, we set different probability thresholds to test the performance of U-Net for the clot detection and selected sensitivity, specificity, and area under the curve (AUC) as the metrics of performance evaluation. Furthermore, we investigated the relationship between the clot burden assessed by the Qanadli score, Mastora score, and other imaging parameters on CTPA and the clot burden calculated by the DL-CNN model.

Results: There was no statistically significant difference in AUCs with the different probability thresholds. When the probability threshold for segmentation was 0.1, the sensitivity and specificity of U-Net in detecting clot respectively were 94.6% and 76.5% while the AUC was 0.926 (95% CI 0.884-0.968). Moreover, this study displayed that the clot burden measured with U-Net was significantly correlated with the Qanadli score (r = 0.819, p < 0.001), Mastora score (r = 0.874, p < 0.001), and right ventricular functional parameters on CTPA.

Conclusions: DL-CNN achieved a high AUC for the detection of pulmonary emboli and can be applied to quantitatively calculate the clot burden of APE patients, which may contribute to reducing the workloads of clinicians.

Key Points: • Deep learning can detect APE with a good performance and efficiently calculate the clot burden to reduce the physicians' workload. • Clot burden measured with deep learning highly correlates with Qanadli and Mastora scores of CTPA. • Clot burden measured with deep learning correlates with parameters of right ventricular function on CTPA.
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http://dx.doi.org/10.1007/s00330-020-06699-8DOI Listing
June 2020

Particle Image Velocimetry (PIV) Investigation of the Turbulent Airflow in Slot-Die Melt Blowing.

Polymers (Basel) 2020 Jan 31;12(2). Epub 2020 Jan 31.

State Key Lab of Chemical Engineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.

In order to explore the forming mechanism of the fiber whipping motion in slot-die melt blowing, the turbulent airflow in slot-die melt blowing was measured online with the approach of the Particle Image Velocimetry (PIV) technique. The PIV results visualized the structure of the turbulent airflow and provided the distributions of air velocity components (, , and ). Moreover, the PIV results also demonstrated the evolutive process of turbulent airflow at successive time instants. By comparing the characteristics of the turbulent airflow with the fiber whipping path, the PIV results provide a preliminary explanation for the specific fiber whipping motion in slot-die melt blowing.
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http://dx.doi.org/10.3390/polym12020279DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7077474PMC
January 2020

Association between infection and health Outcomes: an umbrella review of systematic reviews and meta-analyses.

BMJ Open 2020 01 9;10(1):e031951. Epub 2020 Jan 9.

Department of Administration, The First Affiliated Hospital of Guangxi University of Chinese Medicine, Nanning, Guangxi, China

Objective: Systematic reviews and meta-analyses have revealed the associations between infection and various health outcomes. We aimed to evaluate the strength and breadth of evidence on the associations.

Design: Umbrella review of systematic reviews and meta-analyses.

Setting: No settings.

Participants: No patients involved.

Data Sources: Embase, PubMed, Web of Science, Cochrane Library Databases, CNKI, VIP database and Wangfang database from inception to February 1, 2019.

Outcomes Measures: Diverse diseases (such as cancer and ischaemic heart disease).

Results: Sixty articles reporting 88 unique outcomes met the eligible criteria. 74 unique outcomes had nominal significance (p<0.05). Of the outcomes with significance, 61 had harmful associations and 13 had beneficial associations. Furthermore, 73% (64) of the outcomes exhibited significant heterogeneity . Of the these meta-analyses, 32 had moderate to high heterogeneity (I=50%-75%) and 24 had high heterogeneity (I>75%). Moreover, 20% exhibited publication bias (p<0.1). In addition, 97% of the methodological qualities were rated 'critically low'. 36% of the evidence qualities of outcomes were rated 'low', 56% of the evidence qualities were rated 'very low' and 8% of the evidence qualities were rated 'moderate'. infection may be associated with an increased risk of five diseases and a decreased risk of irritable bowel syndrome.

Conclusion: Although 60 meta-analyses explored 88 unique outcomes, moderate quality evidence only existed for six outcomes with statistical significance. infection may be associated with a decreased risk of irritable bowel syndrome and an increased risk of hypertriglyceridemia, chronic cholecystitis and cholelithiasis, gestational diabetes mellitus, gastric cancer and systemic sclerosis.

Trial Registration: CRD42019124680.
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http://dx.doi.org/10.1136/bmjopen-2019-031951DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6955574PMC
January 2020

Characterizing MRI features of rectal cancers with different KRAS status.

BMC Cancer 2019 Nov 14;19(1):1111. Epub 2019 Nov 14.

Department of Radiology, China-Japan Friendship Hospital, No.2 Yinghua East Street, Chaoyang District, Beijing, 100029, People's Republic of China.

Background: To investigate whether MRI findings, including texture analysis, can differentiate KRAS mutation status in rectal cancer.

Methods: Totally, 158 patients with pathologically proved rectal cancers and preoperative pelvic MRI examinations were enrolled. Patients were stratified into two groups: KRAS wild-type group (KRAS group) and KRAS mutation group (KRAS group) according to genomic DNA extraction analysis. MRI findings of rectal cancers (including texture features) and relevant clinical characteristics were statistically evaluated to identify the differences between the two groups. The independent samples t test or Mann-Whitney U test were used for continuous variables. The differences of the remaining categorical polytomous variables were analyzed using the Chi-square test or Fisher exact test. A receiver operating characteristic (ROC) curve analysis was performed to evaluate the discriminatory power of MRI features. The area under the ROC curve (AUC) and the optimal cut-off values were calculated using histopathology diagnosis as a reference; meanwhile, sensitivity and specificity were determined.

Results: Mean values of six texture parameters (Mean, Variance, Skewness, Entropy, gray-level nonuniformity, run-length nonuniformity) were significantly higher in KRAS group compared to KRAS group (p < 0.0001, respectively). The AUC values of texture features ranged from 0.703~0.813. In addition, higher T stage and lower ADC values were observed in the KRAS group compared to KRAS group (t = 7.086, p = 0.029; t = - 2.708, p = 0.008).

Conclusion: The MRI findings of rectal cancer, especially texture features, showed an encouraging value for identifying KRAS status.
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http://dx.doi.org/10.1186/s12885-019-6341-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6857233PMC
November 2019

Photoactivatable Fluorogens by Intramolecular C-H Insertion of Perfluoroaryl Azide.

J Org Chem 2019 11 29;84(22):14520-14528. Epub 2019 Oct 29.

Department of Chemistry , University of Massachusetts Lowell , Lowell , Massachusetts 01854 , United States.

Molecules, capable of fluorescence turn-on by light, are highly sought-after in spatio-temporal labeling, surface patterning, monitoring cellular and molecular events, and high-resolution fluorescence imaging. In this work, we report a fluorescence turn-on system based on photoinitiated intramolecular C-H insertion of azide into the neighboring aromatic ring. The azide-masked fluorogens were efficiently synthesized via a cascade nucleophilic aromatic substitution of perfluoroaryl azides with carbazoles. The scaffold also allows for derivatization with biological ligands, as exemplified with d-mannose in this study. This photoinitiated intramolecular transformation led to high yields, high photo-conversion efficiency, and well-separated wavelengths for photoactivation and fluorescence excitation. The mannose-derivatized structure enabled spatio-temporal activation and showed high contrast and signal amplification. Live cell imaging suggested that the mannose-tagged fluorogen was transported to the lysosomes.
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http://dx.doi.org/10.1021/acs.joc.9b02050DOI Listing
November 2019

A Versatile Catalyst-Free Perfluoroaryl Azide-Aldehyde-Amine Conjugation Reaction.

Mater Chem Front 2019 Feb 4;3(2):251-256. Epub 2018 Dec 4.

Department of Chemistry, KTH-Royal Institute of Technology, Stockholm, Sweden.

A tri-component reaction, involving an electrophilically-activated perfluoroaryl azide, an enolizable aldehyde and an amine, reacts readily at room temperature without any catalysts in solvents including aqueous conditions to yield a stable amidine conjugate. The versatility of this reaction is demonstrated in the conjugation of an amino acid without prior protection of the carboxyl group, and in the synthesize antibiotic-nanoparticle conjugates.
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http://dx.doi.org/10.1039/C8QM00516HDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6754110PMC
February 2019

Automatic segmentation of arterial tree from 3D computed tomographic pulmonary angiography (CTPA) scans.

Comput Assist Surg (Abingdon) 2019 10 10;24(sup2):79-86. Epub 2019 Aug 10.

Department of Radiology, China-Japan Friendship Hospital , Beijing , China.

Pulmonary embolism (PE) and other pulmonary vascular diseases, have been found associated with the changes in arterial morphology. To detect arterial changes, we propose a novel, fully automatic method that can extract pulmonary arterial tree in computed tomographic pulmonary angiography (CTPA) images. The approach is based on the fuzzy connectedness framework, combined with 3D vessel enhancement and Harris Corner detection to achieve accurate segmentation. The effectiveness and robustness of the method is validated in clinical datasets consisting of 10 CT angiography scans (6 without PE and 4 with PE). The performance of our method is compared with manual classification and machine learning method based on random forest. Our method achieves a mean accuracy of 92% when compared to manual reference, which is higher than the 89% accuracy achieved by machine learning. This performance of the segmentation for pulmonary arteries may provide a basis for the CAD application of PE.
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http://dx.doi.org/10.1080/24699322.2019.1649077DOI Listing
October 2019

Effects of hypogonadism on brain development during adolescence in girls with Turner syndrome.

Hum Brain Mapp 2019 12 7;40(17):4901-4911. Epub 2019 Aug 7.

State Key Laboratory of Cognitive Neuroscience and Learning &IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.

Gonadal steroids play an important role in brain development, particularly during puberty. Girls with Turner syndrome (TS), a genetic disorder characterized by the absence of all or part of the second X chromosome, mostly present a loss of ovarian function and estrogen deficiency, as well as neuroanatomical abnormalities. However, few studies have attempted to isolate the indirect effects of hormones from the direct genetic effects of X chromosome insufficiency. Brain structural (i.e., gray matter [GM] morphology and white matter [WM] connectivity) and functional phenotypes (i.e., resting-state functional measures) were investigated in 23 adolescent girls with TS using multimodal MRI to assess the role of hypogonadism in brain development in TS. Specifically, all girls with TS were divided into a hormonally subnormal group and an abnormal subgroup according to their serum follicle-stimulating hormone (FSH) levels, with the karyotypes approximately matched between the two groups. Statistical analyses revealed significant effects of the "group-by-age" interaction on GM volume around the left medial orbitofrontal cortex and WM diffusion parameters around the bilateral corticospinal tract, anterior thalamic radiation, left superior longitudinal fasciculus, and cingulum bundle, but no significant "group-by-age" or group differences were observed in resting-state functional measures. Based on these findings, estrogen deficiency has a nontrivial impact on the development of the brain structure during adolescence in girls with TS. Our present study provides novel insights into the mechanism by which hypogonadism influences brain development during adolescence in girls with TS, and highlights the important role of estrogen replacement therapy in treating TS.
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http://dx.doi.org/10.1002/hbm.24745DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6865434PMC
December 2019

Lactate Dehydrogenase-to-Lymphocyte Ratio Represents a Powerful Prognostic Tool of Metastatic Renal Cell Carcinoma Patients Treated with Tyrosine Kinase Inhibitors.

Pathol Oncol Res 2020 Apr 6;26(2):1319-1324. Epub 2019 Aug 6.

Department of Emergency, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China.

Inflammation parameters were verified to predict clinical outcomes of metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase inhibitors (TKIs). Here, we developed a novel marker, lactate dehydrogenase (tumor burden marker) to lymphocytes (inflammation marker) ratio (LLR), aimed to reveal the prognostic role of LLR for mRCC patients treated with TKIs. We collected clinical data of mRCC patients treated with TKIs. Receiver operating curve analysis was used to determine the optimal cut-off value. The c-index method was used to determine the best predictive marker for overall survival (OS). Clinicopathological characteristics on OS and progression-free survival (PFS) were evaluated by univariate analysis, and multivariate analyses. LLR provided the greatest improvement in the c-index, and displayed the best marker of the prognostic accuracy for OS. Univariate analysis revealed that LLR, ECOG PS and IMDC risks were significant predictors of OS and PFS. However, multivariate analysis indicated that IMDC risks failed to predict PFS, and only showed predictor of OS. We finally stratifed patients into low LLR (<150) and high LLR (≥150) group with different clinical outcomes. LLR represents a powerful prognostic tool of clinical outcome in mRCC patients treated with TKIs.
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http://dx.doi.org/10.1007/s12253-019-00707-zDOI Listing
April 2020

Specific and Quantitative Detection of Albumin in Biological Fluids by Tetrazolate-Functionalized Water-Soluble AIEgens.

ACS Appl Mater Interfaces 2019 Aug 7;11(33):29619-29629. Epub 2019 Aug 7.

State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering , Hunan University , Changsha 410082 , China.

The analysis of albumin has clinical significance in diagnostic tests and obvious value to research studies on the albumin-mediated drug delivery and therapeutics. The present immunoassay, instrumental techniques, and colorimetric methods for albumin detection are either expensive, troublesome, or insensitive. Herein, a class of water-soluble tetrazolate-functionalized derivatives with aggregation-induced emission (AIE) characteristics is introduced as novel fluorescent probes for albumin detection. They can be selectively lighted up by site-specific binding with albumin. The resulting albumin fluorescent assay exhibits a low detection limit (0.21 nM), high robustness in aqueous buffer (pH = 6-9), and a broad tunable linear dynamic range (0.02-3000 mg/L) for quantification. The tetrazolate functionality endows the probes with a superior water solubility (>0.01 M) and a high binding affinity to albumin ( = 0.25 μM). To explore the detection mechanism, three unique polar binding sites on albumin are computationally identified, where the multivalent tetrazolate-lysine interactions contribute to the tight binding and restriction of the molecular motion of the AIE probes. The key role of lysine residues is verified by the detection of poly-l-lysine. Moreover, we applied the fluorogenic method to quantify urinary albumin in clinical samples and found it a feasible and practical strategy for albumin analysis in complex biological fluids.
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http://dx.doi.org/10.1021/acsami.9b10359DOI Listing
August 2019

Automated robot-assisted assessment for wrist active ranges of motion.

Med Eng Phys 2019 09 15;71:98-101. Epub 2019 Jul 15.

School of Electronic and Electrical Engineering, The University of Leeds, Leeds, United Kingdom.

The measurement of wrist active range of motion (ROM) is essential for determining the progress of hand functional recovery, which can provide insight into quantitative improvements and enable effective monitoring during hand rehabilitation. Compared with manual methods, which depend on the experience of the therapist, the proposed robot-assisted assessment technique can measure active ROM of human wrists. The robot with a reconfigurable handle design allows for multiple wrist motions. Experiments were conducted with 11 human subjects to measure ROMs of human wrist flexion/extension and radial/ulnar deviation. Reliability analysis was conducted by calculating the intra-class correlation coefficients (ICC), standard error of measurement (SEM) and SEM%. Results showed high reliability (ICC ≥ 0.89, SEM ≤ 2.36°, SEM% ≤ 6.81%). Future will focus on adaptive joint self-alignment design between human users and robots to further improve its assessment accuracy.
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http://dx.doi.org/10.1016/j.medengphy.2019.07.003DOI Listing
September 2019

Spiro-Functionalized Diphenylethenes: Suppression of a Reversible Photocyclization Contributes to the Aggregation-Induced Emission Effect.

J Am Chem Soc 2019 06 18;141(25):9803-9807. Epub 2019 Jun 18.

Department of Chemistry , Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Institute for Advanced Study and HKUST-Shenzhen Research Institute, The Hong Kong University of Science & Technology , Hong Kong , China.

Many aggregation-induced emission (AIE) materials are featured by the diphenylethene (DPE) moiety which exhibits rich photophysical and photochemical activities. The understanding of these activities behind AIE is essential to guide the design of fluorescent materials with improved performance. Herein by fusing a flexible DPE with a rigid spiro scaffold, we report a class of novel deep-blue material with solid-state fluorescent quantum yield (Φ) up to 99.8%. Along with the AIE phenomenon, we identified a reversible photocyclization (PC) on DPE with visible chromism, which is, on the contrary, popularized in solutions but blocked by aggregation. We studied the steric and electronic effects of structural perturbation and concluded that the PC is a key process behind the RIMs (restriction of intramolecular motions) mechanism for these materials. Mitigation of the PC leads to enhanced fluorescence in solutions and loss of the AIE characteristics.
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http://dx.doi.org/10.1021/jacs.9b04426DOI Listing
June 2019

Fluorescent Silver Staining of Proteins in Polyacrylamide Gels.

J Vis Exp 2019 04 21(146). Epub 2019 Apr 21.

Ming Wai Lau Centre for Reparative Medicine, Karolinska Institutet;

Silver staining is a colorimetric technique widely used to visualize protein bands in polyacrylamide gels following sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The classic silver stains have certain drawbacks, such as high background staining, poor protein recovery, low reproducibility, a narrow linear dynamic range for quantification, and limited compatibility with mass spectrometry (MS). Now, with the use of a fluorogenic Ag probe, TPE-4TA, we developed a fluorescent silver staining method for the total protein visualization in polyacrylamide gels. This new stain avoids the troublesome silver reduction step in traditional silver stains. Moreover, the fluorescent silver stain demonstrates good reproducibility, sensitivity, and linear quantification in protein detection, making it a useful and practical protein gel stain.
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http://dx.doi.org/10.3791/58669DOI Listing
April 2019