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1.
IEEE Trans Biomed Eng ; PP2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33606624

RESUMO

OBJECTIVE: Biopsies are the gold standard for clinical diagnosis. However, a discrepancy between the biopsy sample and target tissue because of misplacement of the biopsy spoon can lead to errors in the diagnosis and subsequent treatment. Thus, correctly determining whether the needle tip is in the tumor is crucial for accurate biopsy results. METHODS: A biopsy needle system was designed with a steerable, flexible, and superelastic concentric tube; electrodes to monitor the electrical resistivity; and load cells to monitor the insertion force. The degrees of freedom were analyzed for two working modes: straight-line and deflection. RESULTS: Experimental results showed that the system could perceive the tissue type in real-time based on the electrical resistivity. In addition, changes in the insertion force indicated transitions between the interfaces of adjacent tissue layers. CONCLUSION: The two monitoring methods guarantee that the biopsy spoon is at the desired position inside the tumor during an operation. SIGNIFICANCE: The proposed biopsy needle system can be integrated into an autonomous robotic biopsy system.

2.
Med Biol Eng Comput ; 59(3): 663-672, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33594630

RESUMO

Superselective intraarterial infusion chemoradiotherapy is a modality of oral cancer therapy in which the artery feeding the tumor is catheterized. 3D information about the carotid artery is required to enable the surgeon to judge whether to advance, retract, or rotate the catheter. For this purpose, we proposed and conducted a model experiment to assess a new method of catheterization that applies a tracking system using registration with a monocular camera using the maxillary arch as the anatomical landmark. In this method, the preoperative 3D computer tomography angiographic image of the carotid artery that the catheter will be passed through is overlaid on the 2D video image. The mean TRE was 0.96 ± 0.36 mm and 0.88 ± 0.31 mm and 1.12 ± 0.46 mm when images were registered with the anterior and posterior teeth as the landmarks, respectively; the difference was not significant (p = 0.21). This tracking system that enables markerless registration simply by taking images of the maxillary anterior teeth with a single camera was convenient and effective for catheterization. In this study, we propose the new application of this tracking system and a novel method of catheterization for superselective intraarterial infusion chemoradiotherapy for oral cancer. In retrograde superselective intraarterial catheterization, a catheter is inserted into a tumor-feeding artery originating from the external carotid artery (ECA) (the lingual artery [LA], facial artery [FA], or maxillary artery [MA]). Because the maxillary dentition is located near the external carotid artery, we focused on real-time markerless registration using maxillary dentition fixed to the skull.

3.
Int J Med Robot ; 17(2): e2229, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33462998

RESUMO

BACKGROUND: Automatic segmentation of temporal bone structures from patients' conventional computed tomography (CT) data plays an important role in the image-guided cochlear implant surgery. Existing convolutional neural network approaches have difficulties in segmenting such small tubular structures. METHODS: We propose a light-weight three-dimensional convolutional neural network referred to as W-Net to achieve multiobjective segmentation of temporal bone structures including the cochlear labyrinth, ossicular chain and facial nerve from conventional temporal bone CT images. Data augmentation with morphological enhancement is proposed to increase the segmentation accuracy of small tubular structures. Evaluation against the state-of-the-art methods is performed. RESULTS: Our method achieved mean Dice similarity coefficients (DSCs) of 0.90, 0.85 and 0.77 for the cochlear labyrinth, ossicular chain and facial nerve, respectively. These results were also close to the DSCs between human expert annotators (0.91, 0.91 and 0.72). CONCLUSIONS: Our method achieves human-level accuracy in the segmentation of the cochlear labyrinth, ossicular chain and facial nerve.

4.
In Vivo ; 35(1): 275-281, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33402474

RESUMO

BACKGROUND/AIM: We investigated pelvic arterial deformation and shift due to intraoperative pneumoperitoneum and postural changes in an animal model. MATERIALS AND METHODS: Computed tomography images of pigs were acquired in different body positions (supine, head down at 5° and 10°, right lateral recumbent at 5° and 15°) before and after insufflation. We used a free software (3D Slicer) for image analysis. After landmark registration using 10 markers inserted into the pelvis, pelvic arterial deformation and shift of seven arterial bifurcation points were evaluated. The distance moved was the target registration error (TRE) from the points registered in the supine position. Fiducial registration error (FRE) was measured using the 10 pelvic markers. RESULTS: TRE average from postural changes ranged from 0.7 to 1.2 mm and was 1.4 mm due to pneumoperitoneum. TRE and FRE averages were 2.1 mm and 0.2 mm, respectively. CONCLUSION: The pelvis was useful for registering anatomical landmarks.

5.
Artigo em Chinês | MEDLINE | ID: mdl-33254288

RESUMO

Objective:To study the feasibility of fully automatic segmentation of labyrinth, facial nerve and ossicles in clinical routine temporal bone CT images based on 3D U-net neural network. Method:Clinical data were divided into two groups: ①Normal group: data were randomly assigned from 30 patients for routine temporal bone CT examination; ②Abnormal group: cochlear, ossicles and facial nerve morphology variation of 1 case each. The structures of facial nerve, labyrinth and ossicles were manually initial segmented and fine segmented by 2 clinicians with Mimics 20.0. Three-dimensional convolutional neural network(3D U-Net) was selected to conduct deep learning on the same data. The dice similarity coefficient(DSC) was used as the evaluation index. Result:The 3D U-net neural network was used to automatically segment the labyrinth, ossicles and facial nerve in the routine temporal bone CT. In the normal group, the DSC of labyrinth, ossicles and facial nerve were 0.79±0.03, 0.64±0.05 and 0.49±0.09, respectively. In the abnormal group, the DSC of these structures were 0.71, 0.54 and 0.40. Conclusion:According to the anatomical characteristics of the temporal bone, the labyrinth, ossicles and the facial nerve can be totally automatic segmented by 3D U-net neural network, and the accuracy was closed to that of manual segmentation. This method is feasible, fast and accurate.

6.
PeerJ ; 8: e9609, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240581

RESUMO

Sophora moorcroftiana is a perennial leguminous low shrub endemic to the Yarlung Zangbo River basin in Tibet with irreplaceable economic and ecological value. To determine the drivers of evolution in this species, 225 individuals belonging to 15 populations from different geographic locations were sampled, and population genetics was studied using high-throughput genotyping-by-sequencing (GBS). Based on genetic diversity analysis, phylogenetic analysis, principal component analysis, and structure analysis, 15 natural populations were clustered into the following five subgroups: subgroup I (Shigatse subgroup) was located in the upper reaches of the Yarlung Zangbo River with a relatively high level of population genetic variation (means for PIC, Shannon and PI were 0.173, 0.326 and 0.0000305, respectively), and gene flow within the subgroup was also high (mean value for Nm was 4.67). Subgroup II (including Pop 7 and Pop 8; means for PIC, Shannon and PI were 0.182, 0.345 and 0.0000321, respectively), located in the middle reaches of the Yarlung Zangbo River had relatively high levels of gene flow with the populations distributed in the upper and lower reaches. The Nm between subgroup II with subgroups I and III was 3.271 and 2.894, respectively. Considering all the genetic diversity indices Pop 8 had relatively high genetic diversity. Subgroup III (the remaining mixed subgroup of Lhasa and Shannan) was located in the middle reaches of the Yarlung Zangbo River and the means for PIC, Shannon and PI were 0.172, 0.324 and 0.0000303, respectively. Subgroup IV (Nyingchi subgroup), located in the lower reaches of the Yarlung Zangbo River basin, showed a further genetic distance from the other subgroups and the means for PIC, Shannon and PI were 0.147, 0.277 and 0.0000263, respectively. Subgroup V (Nyingchi Gongbu Jiangda subgroup), located in the upper reaches of the Niyang River, had the lowest level of genetic variation (means for PIC, Shannon and PI were 0.106, 0.198 and 0.0000187, respectively) and gene flow with other populations (mean value for Nm was 0.42). According to the comprehensive analysis, the S. moorcroftiana populations generally expanded from upstream to downstream and displayed a high level of genetic differentiation in the populations in the upper and lower reaches. There were high levels of gene exchange between the central populations with upstream and downstream populations, and wind-induced seed dispersal was an important factor in the formation of this gene exchange mode.

7.
Surg Endosc ; 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33185764

RESUMO

BACKGROUND: Laparoscopic lateral pelvic lymph node dissection (LPLND) in rectal cancer surgery requires considerable skill because the pelvic arteries, which need to be located to guide the dissection, are covered by other tissues and cannot be observed on laparoscopic views. Therefore, surgeons need to localize the pelvic arteries accurately before dissection, to prevent injury to these arteries. METHODS: This report proposes a surgical navigation system to facilitate artery localization in laparoscopic LPLND by combining ultrasonic imaging and laparoscopy. Specifically, free-hand laparoscopic ultrasound (LUS) is employed to capture the arteries intraoperatively in this approach, and a laparoscopic vision-based tracking system is utilized to track the LUS probe. To extract the artery contours from the two-dimensional ultrasound image sequences efficiently, an artery extraction framework based on local phase-based snakes was developed. After reconstructing the three-dimensional intraoperative artery model from ultrasound images, a high-resolution artery model segmented from preoperative computed tomography (CT) images was rigidly registered to the intraoperative artery model and overlaid onto the laparoscopic view to guide laparoscopic LPLND. RESULTS: Experiments were conducted to evaluate the performance of the vision-based tracking system, and the average reconstruction error of the proposed tracking system was found to be 2.4 mm. Then, the proposed navigation system was quantitatively evaluated on an artery phantom. The reconstruction time and average navigation error were 8 min and 2.3 mm, respectively. A navigation system was also successfully constructed to localize the pelvic arteries in laparoscopic and open surgeries of a swine. This demonstrated the feasibility of the proposed system in vivo. The construction times in the laparoscopic and open surgeries were 14 and 12 min, respectively. CONCLUSIONS: The experimental results showed that the proposed navigation system can guide laparoscopic LPLND and requires a significantly shorter setting time than the state-of-the-art navigation systems do.

8.
J Craniofac Surg ; 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32969928

RESUMO

To investigate the degree of fusion in sutures of the skull, the authors analyzed cranial computed tomography (CT) data using digital technologies to obtain the density values of coronal, sagittal, and lambdoid sutures in Chinese Han adolescents.The authors selected 80 patients who had undergone maxillofacial surgery. They were divided by age into a 9- to 12-year-old group and a 13 to 15-year-old group. The grayscale value of the cranial CT suture was segmented and measured using Mimics 20.0 software. The Mimics software measurement data were imported into SPSS 21.0 for data comparison and analysis.The mean grayscale value of coronal sutures was 1203.25 and the standard deviation was 220.48, while the mean grayscale value of sagittal sutures was 1113.76 and the standard deviation was 197.83. The mean grayscale value of lambdoid sutures was 1106.37, and the standard deviation was 200.01. The grayscale values of coronal sutures were higher than those of sagittal sutures or lambdoid sutures. Further paired sample t tests were performed on the 3 types of cranial sutures. The differences between coronal and sagittal sutures and between coronal and lambdoid sutures were both substantial with statistical significance. Nevertheless, the difference between sagittal and lambdoid sutures was not significant. Further, an independent sample t-test, showed the grayscale values of coronal, sagittal and lambdoid sutures in the 9-12-year)ear-old group were significantly lower than those in the 13 to 15-year-old group (P < 0.001).Through digital technologies, the research findings are more precise and accurate, which is of great significance to research on maxillofacial and associated anatomy.

9.
BMC Genomics ; 21(1): 609, 2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32891118

RESUMO

BACKGROUND: Phytohormones are the key factors regulating vascular development in plants, and they are also involved in tension wood (TW) formation. Although the theory of hormone distribution in TW formation is widely supported, the effects of endogenous hormones on TW formation have not yet been assessed. In this study, TW formation was induced in Catalpa bungei by artificial bending. The phytohormone content of TW, opposite wood (OW) and normal wood (NW) was determined using liquid chromatography-mass spectrometry (LC-MS), and transcriptome sequencing was performed. The hormone content and related gene expression data were comprehensively analyzed. RESULTS: The results of analyses of the plant hormone contents indicated significantly higher levels of cis-zeatin (cZ), indoleacetic acid (IAA) and abscisic acid (ABA) in TW than in OW. Genes involved in the IAA and ABA synthesis pathways, such as ALDH (evm. MODEL: group5.1511) and UGT (evm. MODEL: scaffold36.20), were significantly upregulated in TW. and the expression levels of ARF (evm. MODEL: group5.1332), A-ARR (evm. MODEL: group0.1600), and TCH4 (evm. MODEL: group2.745), which participate in IAA, cZ and Brassinolide (BR) signal transduction, were significantly increased in TW. In particular, ARF expression may be regulated by long noncoding RNAs (lncRNAs) and the HD-ZIP transcription factor ATHB-15. CONCLUSIONS: We constructed a multiple hormone-mediated network of C. bungei TW formation based on hormone levels and transcriptional expression profiles were identified during TW formation.

10.
Int J Comput Assist Radiol Surg ; 15(6): 989-999, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32361857

RESUMO

PURPOSE: The surface-based registration approach to laparoscopic augmented reality (AR) has clear advantages. Nonrigid point-set registration paves the way for surface-based registration. Among current non-rigid point set registration methods, the coherent point drift (CPD) algorithm is rarely used because of two challenges: (1) volumetric deformation is difficult to predict, and (2) registration from intraoperative visible tissue surface to whole anatomical preoperative model is a "part-to-whole" registration that CPD cannot be applied directly to. We preliminarily applied CPD on surgical navigation for laparoscopic partial nephrectomy (LPN). However, it introduces normalization errors and lacks navigation robustness. This paper presents important advances for more effectively applying CPD to LPN surgical navigation while attempting to quantitatively evaluate the accuracy of CPD-based surgical navigation. METHODS: First, an optimized volumetric deformation (Op-VD) algorithm is proposed to achieve accurate prediction of volume deformation. Then, a projection-based partial selection method is presented to conveniently and robustly apply the CPD to LPN surgical navigation. Finally, kidneys with different deformations in vitro, phantom and in vivo experiments are performed to evaluate the accuracy and effectiveness of our approach. RESULTS: The average root-mean-square error of volume deformation was refined to 0.84 mm. The mean target registration error (TRE) of the surface and inside markers in the in vitro experiments decreased to 1.51 mm and 1.29 mm, respectively. The robustness and precision of CPD-based navigation were validated in phantom and in vivo experiments, and the mean navigation TRE of the phantom experiments was found to be [Formula: see text] mm. CONCLUSION: Accurate volumetric deformation and robust navigation results can be achieved in AR navigation of LPN by using surface-based registration with CPD. Evaluation results demonstrate the effectiveness of our proposed methods while showing the clinical application potential of CPD. This work has important guiding significance for the application of the CPD in laparoscopic AR.


Assuntos
Realidade Aumentada , Rim/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Cirurgia Assistida por Computador/métodos , Algoritmos , Humanos , Imagens de Fantasmas
11.
Int J Chron Obstruct Pulmon Dis ; 15: 3407-3416, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408470

RESUMO

Background: Chronic obstructive pulmonary disease (COPD) is an age-related disease, and its incidence rate is increasing every year. MicroRNAs (miRNAs) play critical roles in the COPD process and function as key biomarkers or potential therapeutic targets for patients with COPD. However, the potential roles and functional effects of miR-218 in COPD remain undefined. Methods: The expression levels of miR-218 and bromodomain protein 4 (BRD4) were assessed by real-time quantitative polymerase chain reaction (RT-qPCR) or Western blot, respectively. In addition, a COPD cell model was established using cigarette smoke extract (CSE) in bronchial epithelial cell line (BEAS-2B). Enzyme-linked immunosorbent assay (ELISA) kit was applied to measure the concentrations of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8) in cell supernatants of BEAS-2B cells. Moreover, cell apoptosis was examined by flow cytometry assay. The association relationship between miR-218 and BRD4 was confirmed by dual-luciferase reporter and RNA immunoprecipitation assay. Results: MiR-218 was downregulated in COPD and CSE-induced BEAS-2B cells, and it was positively correlated with forced expiratory volume in 1 second (FEV1) % in COPD patients. Mechanically, overexpression of miR-218 or knockdown of BRD4 mitigated apoptosis and inflammation in BEAS-2B cells induced by CSE. Additionally, overexpression of BRD4 weakened the miR-218-mediated effects on CSE-induced BEAS-2B cells. Conclusion: Overexpression of miR-218 inhibited CSE-induced apoptosis and inflammation in BEAS-2B cells by targeting BRD4 expression.

12.
Technol Health Care ; 27(S1): 229-238, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31045542

RESUMO

BACKGROUND: Previous studies showed that compared with single-bundle (SB) precedures, double-bundle (DB) anterior cruciate ligament (ACL) reconstruction perform better. OBJECTIVE: To make assurance that distance of TT-TG may be altered along with ACL rupture and reconstruction. METHODS: Imaging study of 201 patients's related cases by MRI and CT scans. RESULTS: Compared with the intact knee's overall mean TT-TG value, the mean overall pre/postoperative TT-TG values showed a significant difference. For SB reconstruction, the mean pre/postoperative TT-TG values were 15.67± 2.46 mm and 14.72± 2.48 mm, respectively. Postoperative and intact knee TT-TG values were significantly different (p< 0.001). For DB reconstruction, the pre/postoperative mean TT-TG values were 15.11± 1.99 mm and 13.11± 1.71 mm. Postoperative and intact knee TT-TG values were not significantly different (p= 0.141). CONCLUSIONS: The increased TT-TG value from a ruptured ACL was significantly restored after ACL reconstruction. The TT-TG value after SB reconstruction was still obviously larger than that of the intact knee. It showed no significant difference between the postoperative TT-TG of the DB group and intact knees. The original TT-TG values of the knees were much closer to restoration after DB reconstruction.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/métodos , Tíbia/diagnóstico por imagem , Adolescente , Adulto , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Feminino , Humanos , Instabilidade Articular , Imagem por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tíbia/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
13.
Materials (Basel) ; 12(10)2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31137468

RESUMO

The effects of V vacancy on the thermoelectric performance of the half-Heusler compound VCoSb have been investigated in this study. A certain amount of CoSb secondary phase is generated in the VCoSb matrix when the content of V vacancy is more than 0.1 at%. According to the results, a ZT value of 0.6, together with a power factor of 29 µW cm-1 K-2 at 873 K, were achieved for the nonstoichiometric sample V0.9CoSb. This proved that moderate V vacancy could improve the thermoelectric (TE) properties of VCoSb. The noticeable improvements are mainly owing to the incremental Seebeck coefficient, which may benefit from the optimized carrier concentration. However, too much V vacancy will result in more CoSb impurity and deteriorate the TE performances of VCoSb owing to the increased thermal conductivity.

14.
Genome ; 62(5): 317-328, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30998854

RESUMO

Picea asperata and P. crassifolia have sympatric ranges and are closely related, but the differences between these species at the plastome level are unknown. To better understand the patterns of variation among Picea plastomes, the complete plastomes of P. asperata and P. crassifolia were sequenced. Then, the plastomes were compared with the complete plastomes of P. abies and P. morrisonicola, which are closely and distantly related to the focal species, respectively. We also used these sequences to construct phylogenetic trees to determine the relationships among and between the four species as well as additional taxa from Pinaceae and other gymnosperms. Analysis of our sequencing data allowed us to identify 438 single nucleotide polymorphism (SNPs) point mutation events, 95 indel events, four inversion events, and seven highly variable regions, including six gene spacer regions (psbJ-petA, trnT-psaM, trnS-trnD, trnL-rps4, psaC-ccsA, and rps7-trnL) and one gene (ycf1). The highly variable regions are appropriate targets for future use in the phylogenetic reconstructions of closely related, sympatric species of Picea as well as Pinaceae in general.


Assuntos
Genomas de Plastídeos/genética , Picea/genética , Simpatria , Mutação INDEL , Filogenia , Plastídeos/genética , Polimorfismo de Nucleotídeo Único/genética , Inversão de Sequência/genética
15.
Int J Comput Assist Radiol Surg ; 14(8): 1285-1294, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31016562

RESUMO

Purpose Video see-through augmented reality (VST-AR) navigation for laparoscopic partial nephrectomy (LPN) can enhance intraoperative perception of surgeons by visualizing surgical targets and critical structures of the kidney tissue. Image registration is the main challenge in the procedure. Existing registration methods in laparoscopic navigation systems suffer from limitations such as manual alignment, invasive external marker fixation, relying on external tracking devices with bulky tracking sensors and lack of deformation compensation. To address these issues, we present a markerless automatic deformable registration framework for LPN VST-AR navigation. METHOD: Dense stereo matching and 3D reconstruction, automatic segmentation and surface stitching are combined to obtain a larger dense intraoperative point cloud of the renal surface. A coarse-to-fine deformable registration is performed to achieve a precise automatic registration between the intraoperative point cloud and the preoperative model using the iterative closest point algorithm followed by the coherent point drift algorithm. Kidney phantom experiments and in vivo experiments were performed to evaluate the accuracy and effectiveness of our approach. RESULTS: The average segmentation accuracy rate of the automatic segmentation was 94.9%. The mean target registration error of the phantom experiments was found to be 1.28 ± 0.68 mm (root mean square error). In vivo experiments showed that tumor location was identified successfully by superimposing the tumor model on the laparoscopic view. CONCLUSION: Experimental results have demonstrated that the proposed framework could accurately overlay comprehensive preoperative models on deformable soft organs automatically in a manner of VST-AR without using extra intraoperative imaging modalities and external tracking devices, as well as its potential clinical use.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Rim/diagnóstico por imagem , Laparoscopia , Nefrectomia , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Calibragem , Humanos , Modelos Teóricos , Distribuição Normal , Reconhecimento Automatizado de Padrão , Imagens de Fantasmas , Análise de Componente Principal , Linguagens de Programação , Reprodutibilidade dos Testes
16.
Int J Comput Assist Radiol Surg ; 14(5): 763-773, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30825070

RESUMO

BACKGROUND: Image registration lies in the core of augmented reality (AR), which aligns the virtual scene with the reality. In AR surgical navigation, the performance of image registration is vital to the surgical outcome. METHODS: This paper presents a practical marker-less image registration method for AR-guided oral and maxillofacial surgery where a virtual scene is generated and mixed with reality to guide surgical operation or provide surgical outcome visualization in the manner of video see-through overlay. An intraoral 3D scanner is employed to acquire the patient's teeth shape model intraoperatively. The shape model is then registered with a custom-made stereo camera system using a novel 3D stereo matching algorithm and with the patient's CT-derived 3D model using an iterative closest point scheme, respectively. By leveraging the intraoral 3D scanner, the CT space and the stereo camera space are associated so that surrounding anatomical models and virtual implants could be overlaid on the camera's view to achieve AR surgical navigation. RESULTS: Jaw phantom experiments were performed to evaluate the target registration error of the overlay, which yielded an average error of less than 0.50 mm with the time cost less than 0.5 s. Volunteer trial was also conducted to show the clinical feasibility. CONCLUSIONS: The proposed registration method does not rely on any external fiducial markers attached to the patient. It performs automatically so as to maintain a correct AR scene, overcoming the misalignment difficulty caused by patient's movement. Therefore, it is noninvasive and practical in oral and maxillofacial surgery.


Assuntos
Imageamento Tridimensional/métodos , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Procedimentos Cirúrgicos Bucais/métodos , Imagens de Fantasmas , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Mandíbula/cirurgia , Maxila/cirurgia , Impressão Tridimensional
17.
Int J Med Robot ; 15(4): e1997, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30900789

RESUMO

BACKGROUND: Human-related factors affect the accuracy and safety of the oral and maxillofacial surgery (OMS). This study proposed an autonomous surgical system aiming to conduct the OMS under the assistance and surveillance of the surgeon. METHODS: A markerless navigation module and a compact OMS robot were seamlessly integrated into this system. The specifications of each module and the working concept of the system were elaborated in this paper. A drilling experiment was conducted on five 3D-printed mandible models to test the pose detecting capability and evaluate the operational performance. RESULTS: The experiment showed that this system could successfully guide the robot finishing the operation regardless of the mandible pose. The accuracy of software and hardware are acceptable and potential performance improvement can be achieved in positioning accuracy. CONCLUSION: This system proposed a novel concept and a practical solution to decrease the human-related factors on the OMS, which may change the role of the surgeon in the future operating room and finally benefit the outcomes of OMS.


Assuntos
Mandíbula/cirurgia , Procedimentos Cirúrgicos Bucais , Procedimentos Cirúrgicos Robóticos/métodos , Cirurgia Assistida por Computador/métodos , Desenho de Equipamento , Humanos , Imageamento Tridimensional , Osteotomia , Imagens de Fantasmas , Impressão Tridimensional , Reprodutibilidade dos Testes , Software , Tomografia Computadorizada por Raios X
18.
Gene ; 696: 95-104, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30779945

RESUMO

The high-osmolarity glycerol (HOG) signaling pathway regulates the adaptation of fungi to environmental stressors. The mitogen-activated protein kinase kinase (MAPKK) PBS2 of Saccharomyces cerevisiae serves as a scaffold protein in the HOG pathway. We characterized the pgpbs gene of Pyrenophora graminea, which encodes a MAPKK that is 56% orthologous to PBS2 of S. cerevisiae. A cloning technique based on homology was applied to amplify the pgpbs gene. Specific silent mutations then were generated in pgpbs. We evaluated the potential roles of PGPBS in the osmotic response, vegetative differentiation, cell wall integrity, drug resistance, and pathogenicity. Our findings indicated that the pgpbs coding region comprises 2075 base pairs and encodes a protein of 676 amino acids. Mutants deficient in pgpbs expression had significant reductions in vegetative growth and were sensitive to calcofluor white (CFW), an inhibitor of cell wall synthesis. Mutants also lost pathogenicity and were sensitive to an osmotic stress-inducing medium containing NaCl and sorbitol. Moreover, mutants had increased resistance to the dicarboximide fungicide iprodione and the triazole fungicide tebuconazole. These findings suggest that pgpbs is involved in the osmotic and ionic stress responses, vegetative differentiation, cell wall integrity, virulence, and tolerance to iprodione and tebuconazole. We expect that our findings will help elucidate the pathogenesis of barley leaf stripe and will inform strategies for breeding resistance to this disease.


Assuntos
Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Hordeum/microbiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Doenças das Plantas/microbiologia , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Ascomicetos/genética , Ascomicetos/metabolismo , Benzenossulfonatos/farmacologia , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Parede Celular/metabolismo , Farmacorresistência Fúngica Múltipla/genética , Proteínas Fúngicas/metabolismo , Fungicidas Industriais/farmacologia , Hidantoínas/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mutação , Folhas de Planta/microbiologia , Triazóis/farmacologia , Virulência/genética
19.
Sci Rep ; 8(1): 15250, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30323196

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a common malignant cancer that accounts for 5-10% of all cancers. This study aimed to identify essential genes associated with the prognosis of HNSCC and construct a powerful prognostic model for the risk assessment of HNSCC. RNAseq expression profile data for the patients with HNSCC were obtained from the TCGA database (GEO). A total of 500 samples with full clinical following-up were randomly divided into a training set and a validation set. The training set was used to screen for differentially expressed lncRNAs. Single-factor survival analysis was performed to obtain lncRNAs that associated with prognosis. A robust likelihood-based survival model was constructed to identify the lncRNAs that are essential for the prognosis of HNSCC. A co-expression network between genes and lncRNAs was also constructed to identify lncRNAs co-expressed with genes to serve as the final signature lncRNAs for prognosis. Finally, the prognostic effect of the signature lncRNAs was tested by multi-factor survival analysis and a scoring model for the prognosis of HNSCC was constructed. Moreover, the results of the validation set and the relative expression levels of the signature lncRNAs in the tumour and the adjacent tissue were consistent with the results of the training set. The 5 lncRNAs were distributed among 3 expression modules. Further KEGG pathway enrichment analysis showed that these 3 co-expressed modules participate in different pathways, and many of these pathways are associated with the development and progression of disease. Therefore, we proposed that the 5 validated lncRNAs can be used to predict the prognosis of HNSCC patients and can be applied in postoperative treatment and follow-up.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/genética , RNA Longo não Codificante/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Transcriptoma , Idoso , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Análise de Sobrevida
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(4): 571-577, 2018 08 25.
Artigo em Chinês | MEDLINE | ID: mdl-30124020

RESUMO

Pectus carinatum (PC) is one of the most common chest wall anomalies, which is characterized by the protrusion of the anterior chest wall including the sternum and adjacent costal cartilages. Mildly patients suffer from mental problems such as self-abasement, while severely suffering patients are disturbed by significant cardiopulmonary symptoms. The traditional Haller index, which is widely used clinically to evaluate the severity of PC, is deficient in diagnosis efficiency and classification. This paper presents an improved Haller index algorithm for PC: first, the contour of the patient chest in the axial computed tomography (CT) slice where the most convex thorax presents is extracted; and then a cubic B-spline curve is employed to fit the extracted contour followed by an eclipse fitting procedure; finally, the improved Haller index and the classification index are automatically calculated based on the analytic curves. The results of CT data analysis using 22 preoperative and postoperative patient CT datasets show that the proposed diagnostic index for PC can diagnose and classify PC patients correctly, which confirms the feasibility of the evaluation index. Furthermore, digital measurement techniques can be employed to improve the diagnostic efficiency of PC, achieving one small step towards the computer-aided intelligent diagnosis and treatment for pediatric chest wall malformations.

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