Registration area and accuracy when integrating laser-scanned and maxillofacial cone-beam computed tomography images

Sun, LiJun,Hwang, Hyeon-Shik,Lee, Kyung-Min Elsevier 2018 American journal of orthodontics and dentofacial o Vol.153 No.3

<P><B>Introduction</B></P> <P>The purpose of this study was to examine changes in registration accuracy after including occlusal surface and incisal edge areas in addition to the buccal surface when integrating laser-scanned and maxillofacial cone-beam computed tomography (CBCT) dental images.</P> <P><B>Methods</B></P> <P>CBCT scans and maxillary dental casts were obtained from 30 patients. Three methods were used to integrate the images: R1, only the buccal and labial surfaces were used; R2, the incisal edges of the anterior teeth and the buccal and distal marginal ridges of the second molars were used; and R3, labial surfaces, including incisal edges of anterior teeth, and buccal surfaces, including buccal and distal marginal ridges of the second molars, were used. Differences between the 2 images were evaluated by color-mapping methods and average surface distances by measuring the 3-dimensional Euclidean distances between the surface points on the 2 images.</P> <P><B>Results</B></P> <P>The R1 method showed more discrepancies between the laser-scanned and CBCT images than did the other methods. The R2 method did not show a significant difference in registration accuracy compared with the R3 method.</P> <P><B>Conclusions</B></P> <P>The results of this study indicate that accuracy when integrating laser-scanned dental images into maxillofacial CBCT images can be increased by including occlusal surface and incisal edge areas as registration areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Registration areas were compared for integrating laser-scanned and CBCT images. </LI> <LI> Using facial surfaces only caused the greatest discrepanices. </LI> <LI> Using incisal edge and marginal ridge was comparable with using them plus facial surfaces. </LI> <LI> Incisal edge and marginal ridge are appropriate for integrating laser-scanned and CBCT images. </LI> </UL> </P>

Reproducibility of an intraoral scanner: A comparison between in-vivo and ex-vivo scans

Sun, LiJun,Lee, Jin-Sol,Choo, Hyun-Hee,Hwang, Hyeon-Shik,Lee, Kyung-Min Elsevier 2018 American journal of orthodontics and dentofacial o Vol.154 No.2

<P><B>Introduction</B></P> <P>The purpose of this study was to assess the reproducibility of in-vivo and ex-vivo scans using an intraoral scanner.</P> <P><B>Methods</B></P> <P>Twenty adults with no missing teeth except for third molars were included in the study. Alginate impressions were taken, and plaster models were made from the impressions. Each subject underwent full-arch intraoral scanning twice with a TRIOS scanner (3Shape, Copenhagen, Denmark) at an interval of 2 weeks, and, the plaster models were scanned at the same interval with the same scanner. The first images of each scan were superimposed on the second scanned images using surface-based registration. In each case, the differences between the 2 scanned images were evaluated with color mapping. The reproducibility between the in-vivo and ex-vivo scans was compared using independent <I>t</I> tests and Bland-Altman analysis.</P> <P><B>Results</B></P> <P>The discrepancies between the first and second images were greater in the posterior than in the anterior regions for both the in-vivo and ex-vivo scans. Average surface differences between the first and second images were greater for the in-vivo scans (0.04 mm) than for the ex-vivo scans (0.02 mm). The Bland-Altman plots showed that the reproducibility of both scans was within the limits of agreement.</P> <P><B>Conclusions</B></P> <P>The reproducibility of in-vivo scanning was comparable with ex-vivo scanning, although it showed a slight difference (0.02 mm) compared with ex-vivo scanning.</P> <P><B>Highlights</B></P> <P> <UL> <LI> In-vivo intraoral scanning showed a 0.041-mm average mean difference between 2 scans. </LI> <LI> Ex-vivo intraoral scanning showed a 0.019-mm average mean difference between 2 scans. </LI> <LI> Reproducibility of in-vivo scanning was similar to that of ex-vivo scanning. </LI> </UL> </P>

Overexpression of Rcan1-1L Inhibits Hypoxia-Induced Cell Apoptosis through Induction of Mitophagy

Sun, Lijun,Hao, Yuewen,An, Rui,Li, Haixun,Xi, Cong,Shen, Guohong Korean Society for Molecular and Cellular Biology 2014 Molecules and cells Vol.37 No.11

Mitophagy, a cellular process that selectively targets dysfunctional mitochondria for degradation, is currently a hot topic in research into the pathogenesis and treatment of many human diseases. Considering that hypoxia causes mitochondrial dysfunction, which results in cell death, we speculated that selective activation of mitophagy might promote cell survival under hypoxic conditions. In the present study, we introduced the Regulator of calcineurin 1-1L (Rcan1-1L) to initiate the mitophagy pathway and aimed to evaluate the effect of Rcan1-1L-induced mitophagy on cell survival under hypoxic conditions. Recombinant adenovirus vectors carrying Rcan1-1L were transfected into human umbilical vein endothelial cells and human adult cardiac myocytes. Using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay and Trypan blue exclusion assay, Rcan1-1L overexpression was found to markedly reverse cell growth inhibition induced by hypoxia. Additionally, Rcan1-1L overexpression inhibited cell apoptosis under hypoxic conditions, as detected by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) apoptosis assay. Meanwhile, the mitochondria-mediated cell apoptotic pathway was inhibited by Rcan1-1L. In contrast, knockdown of Rcan1-1L accelerated hypoxia-induced cell apoptosis. Moreover, Rcan1-1L overexpression significantly reduced mitochondrial mass, decreased depolarized mitochondria, and downregulated ATP and reactive oxygen species production. We further delineated that the loss of mitochondrial mass was due to the activation of mitophagy induced by Rcan1-1L. Rcan1-1L overexpression activated autophagy flux and promoted translocation of the specific mitophagy receptor Parkin into mitochondria from the cytosol, whereas inhibition of autophagy flux resulted in the accumulation of Parkin-loaded mitochondria. Finally, we demonstrated that mitochondrial 1permeability transition pore opening was significantly increased by Rcan1-1L overexpression, which suggested that Rcan1-1L might evoke mitophagy through regulating mitochondrial permeability transition pores. Taken together, we provide evidence that Rcan1-1L overexpression induces mitophagy, which in turn contributes to cell survival under hypoxic conditions, revealing for the first time that Rcan1-1L-induced mitophagy may be used for cardioprotection.

Three-Dimensional Evaluation of the Postsurgical Stability of Mandibular Setback With the Surgery-First Approach: Comparison Between Patients With Symmetry and Asymmetry

Sun, LiJun,Lee, Kyung-Min Elsevier 2019 Journal of oral and maxillofacial surgery Vol.77 No.7

<P><B>Purpose</B></P> <P>The purpose of the present study was to evaluate the 3-dimensional postsurgical stability of mandibular setback with a surgery-first (SF) orthodontic treatment approach in patients with skeletal Class III malocclusions and facial asymmetry using cone-beam computed tomographic (CBCT) images.</P> <P><B>Patients and Methods</B></P> <P>Thirty-six patients who underwent mandibular setback with an SF approach for the correction of mandibular prognathism were enrolled in the present study. Patients were divided into symmetrical (n = 18) and asymmetrical (n = 18) groups according to their degree of menton deviation. CBCT images were acquired before surgery, 1, 6, and 12 months after surgery, and at the end of treatment. After reorienting of CBCT images using automatic volume-based registration, the position of the mandible at each time point was evaluated relative to its post-treatment position. MATLAB (MathWorks, Natick, MA) was used to represent all sequential changes in postoperative mandibular position. The increase in posterior vertical dimension at surgery was measured and then correlated with postsurgical mandibular stability.</P> <P><B>Results</B></P> <P>For up to 6 months after surgery, the position of the mandible differed considerably from its post-treatment position. At 12 months after surgery, the position of the mandible no longer differed substantially from its post-treatment position. The asymmetry group exhibited greater outward displacement of the proximal segment. The symmetrical and asymmetrical groups exhibited a positive correlation between postsurgical mandibular instability and the increase in posterior vertical dimension.</P> <P><B>Conclusion</B></P> <P>These results indicate that mandibular position stabilizes 12 months after surgery performed with an SF approach. It is necessary to consider mandibular forward movement from the increase in posterior vertical dimension in surgical occlusion during the treatment planning stage. Moreover, clinicians should maintain the surgical position of proximal segments during postsurgical orthodontic treatment at least until 12 months after surgery.</P>

Overexpression of Rcan1-1L Inhibits Hypoxia-Induced Cell Apoptosis through Induction of Mitophagy

Lijun Sun,Yuewen Hao,Rui An,Haixun Li,Cong Xi,Guohong Shen 한국분자세포생물학회 2014 Molecules and cells Vol.37 No.11

Mitophagy, a cellular process that selectively targets dysfunctional mitochondria for degradation, is currently a hot topic in research into the pathogenesis and treatment of many human diseases. Considering that hypoxia causes mitochondrial dysfunction, which results in cell death, we speculated that selective activation of mitophagy might promote cell survival under hypoxic conditions. In the present study, we introduced the Regulator of calcineurin 1-1L (Rcan1-1L) to initiate the mitophagy pathway and aimed to evaluate the effect of Rcan1-1L-induced mitophagy on cell survival under hypoxic conditions. Recombinant adenovirus vectors carrying Rcan1-1L were transfected into human umbilical vein endothelial cells and human adult cardiac myocytes. Using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay and Trypan blue exclusion assay, Rcan1-1L overexpression was found to markedly reverse cell growth inhibition induced by hypoxia. Additionally, Rcan1-1L overexpression inhibited cell apoptosis under hypoxic conditions, as detected by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) apoptosis assay. Meanwhile, the mitochondria-mediated cell apoptotic pathway was inhibited by Rcan1-1L. In contrast, knockdown of Rcan1-1L accelerated hypoxia-induced cell apoptosis. Moreover, Rcan1-1L overexpression significantly reduced mitochondrial mass, decreased depolarized mitochondria, and downregulated ATP and reactive oxygen species production. We further delineated that the loss of mitochondrial mass was due to the activation of mitophagy induced by Rcan1-1L. Rcan1-1L overexpression activated autophagy flux and promoted translocation of the specific mitophagy receptor Parkin into mitochondria from the cytosol, whereas inhibition of autophagy flux resulted in the accumulation of Parkin-loaded mitochondria. Finally, we demonstrated that mitochondrial permeability transition pore opening was significantly increased by Rcan1-1L overexpression, which suggested that Rcan1-1L might evoke mitophagy through regulating mitochondrial permeability transition pores. Taken together, we provide evidence that Rcan1-1L overexpression induces mitophagy, which in turn contributes to cell survival under hypoxic conditions, revealing for the first time that Rcan1-1L-induced mitophagy may be used for cardioprotection.

Two Novel A-seco-Rearranged Lanostane Triterpenoids From Abies Sachalinensis

Sun, Bohang,Hou, Bailing,Huang, Jian,Wu, Lijun,Kuroyanagi, Masonori,Gao, Huiyuan 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.12

Further chemical study led to two new A-seco-rearranged lanostane triterpenoid derivatives (1-2) and one known compound Abiesanolide C (3) from the ethyl acetate (EtOAc) soluble fraction of the MeOH extract of Abies sachalinensis needles. The new compounds were identified as 3,4-seco-8-($14{\rightarrow}13R$)abeo-17, l3-friedo-$9{\beta}$-lanosta-4(28), 7, 14, 24-tetraen- 26,23-olide-23-hydroxy-3-oic acid and methyl-3,4-seco-8-($14{\rightarrow}13R$) abeo-17,13-friedo-$9{\beta}$-lanosta-4(28), 7, 14, 24-tetraen-26,23-olide-23-hydroxy-3-oate, respectively. Structural determination of these compounds were carried out by the spectral studies especially by the two digital (2D)-NMR and high-resolution (HR)-MS experiences.

Fractal Dimension Analysis of MDCT Images for Quantifying the Morphological Changes of the Pulmonary Artery Tree in Patients with Pulmonary Hypertension

Sun Haitao,Li Ning,Guo Lijun,Gao Fei,Liu Cheng 대한영상의학회 2011 Korean Journal of Radiology Vol.12 No.3

Objective: The aim of this study was to use fractal dimension (FD) analysis on multidetector CT (MDCT) images for quantifying the morphological changes of the pulmonary artery tree in patients with pulmonary hypertension (PH). Materials and Methods: Fourteen patients with PH and 17 patients without PH as controls were studied. All of the patients underwent contrast-enhanced helical CT and transthoracic echocardiography. The pulmonary artery trees were generated using post-processing software, and the FD and projected image area of the pulmonary artery trees were determined with ImageJ software in a personal computer. The FD, the projected image area and the pulmonary artery pressure (PAP) were statistically evaluated in the two groups. Results: The FD, the projected image area and the PAP of the patients with PH were higher than those values of the patients without PH (p < 0.05, t-test). There was a high correlation of FD with the PAP (r = 0.82, p < 0.05, partial correlation analysis). There was a moderate correlation of FD with the projected image area (r = 0.49, p < 0.05, partial correlation analysis). There was a correlation of the PAP with the projected image area (r = 0.65, p < 0.05, Pearson correlation analysis). Conclusion: The FD of the pulmonary arteries in the PH patients was significantly higher than that of the controls. There is a high correlation of FD with the PAP. Objective: The aim of this study was to use fractal dimension (FD) analysis on multidetector CT (MDCT) images for quantifying the morphological changes of the pulmonary artery tree in patients with pulmonary hypertension (PH). Materials and Methods: Fourteen patients with PH and 17 patients without PH as controls were studied. All of the patients underwent contrast-enhanced helical CT and transthoracic echocardiography. The pulmonary artery trees were generated using post-processing software, and the FD and projected image area of the pulmonary artery trees were determined with ImageJ software in a personal computer. The FD, the projected image area and the pulmonary artery pressure (PAP) were statistically evaluated in the two groups. Results: The FD, the projected image area and the PAP of the patients with PH were higher than those values of the patients without PH (p < 0.05, t-test). There was a high correlation of FD with the PAP (r = 0.82, p < 0.05, partial correlation analysis). There was a moderate correlation of FD with the projected image area (r = 0.49, p < 0.05, partial correlation analysis). There was a correlation of the PAP with the projected image area (r = 0.65, p < 0.05, Pearson correlation analysis). Conclusion: The FD of the pulmonary arteries in the PH patients was significantly higher than that of the controls. There is a high correlation of FD with the PAP.

An LDPC-COFDM based High Speed Mobile Wireless Communication System

Hongyu Sun,Lijun Bi,Xiang Lu,Yinjing Guo 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.12

Coded Orthogonal Frequency Division Multiplexing (COFDM) is very well matched to the terrestrial channel, being able to cope with severe multi-path and the presence of co-channel narrowband interference. This paper presents an image and video transmission scheme based on COFDM for high speed mobile wireless communication system in which a good Rate-Compatible Low-Density Parity-Check codes structure is applied, this structure can provide a large range of supporting rates, and provide very good error performance, low decoding latency and low computational complexity at the decoder. The test experiment was made in television live transmitting to validate the designed system. The results show that our COFDM-based mobile wireless digital multimedia broadcasting system can transmit high definition image and video when it being equipped for 486Kilometre/Hour’s high speed rail, The Channel Bit Error Rate <2.0E-4 and Carrier to noise ratio(C/N) >30dB when the output power at 30dBm.

Two Novel A-seco-Rearranged Lanostane Triterpenoids From Abies Sachalinensis

Bohang Sun,Bailing Hou,Jian Huang,Lijun Wu,Masonori Kuroyanagi,Huiyuan Gao 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.12

Further chemical study led to two new A-seco-rearranged lanostane triterpenoid derivatives (1-2) and one known compound Abiesanolide C (3) from the ethyl acetate (EtOAc) soluble fraction of the MeOH extract of Abies sachalinensis needles. The new compounds were identified as 3,4-seco-8-(14→13R)abeo-17,13-friedo-9β-lanosta-4(28), 7, 14, 24-tetraen-26,23-olide-23-hydroxy-3-oic acid and methyl-3,4-seco-8-(14→13R) abeo-17,13-friedo-9β-lanosta-4(28), 7, 14, 24-tetraen-26,23-olide-23- hydroxy-3-oate, respectively. Structural determination of these compounds were carried out by the spectral studies especially by the two digital (2D)-NMR and high-resolution (HR)-MS experiences.

EEG-based Safety Driving Performance Estimation and Alertness Using Support Vector Machine

Hongyu Sun,Lijun Bi,Bisheng Chen,Yinjing Guo 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.6

Safety driving performance estimation and alertness (SDPEA) has drawn the attention of researchers in preventing traffic accidents caused by drowsiness while driving. Psychophysiological measures, such as electroencephalogram (EEG), are accurately investigated to be robust candidates for drivers’ drowsiness evaluation. This paper presents an effective EEG-based driver drowsiness monitoring system by analyzing the changes of brain activities in a simulator driving environment. The proposed SDPEA system can translate EEG signals into drowsiness level. Firstly, Independent component analysis (ICA) is performed on EEG data to remove artifacts. Then, eight EEG-band powers- related features: beta, alpha, theta, delta, (alpha plus theta)/beta, alpha / beta, (alpha plus theta)/(alpha plus beta) and theta / beta are extracted from the preprocessed EEG signals by employing the Fast Fourier Transform (FFT). Subsequently, fisher score technique selects the most descriptive features for further classification. Finally, Support Vector Machine (SVM) is employed as a classifier to distinguish drowsiness level. Experimental results show that the quantitative driving performance can be correctly estimated through analyzing driver’s EEG signals by the SDPEA system.