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1.
Front Oncol ; 10: 1715, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33014850

RESUMEN

Objective: To generate virtual non-contrast (VNC) computed tomography (CT) from intravenous enhanced CT through convolutional neural networks (CNN) and compare calculated dose among enhanced CT, VNC, and real non-contrast scanning. Method: 50 patients who accepted non-contrast and enhanced CT scanning before and after intravenous contrast agent injections were selected, and two sets of CT images were registered. A total of 40 and 10 groups were used as training and test datasets, respectively. The U-Net architecture was applied to learn the relationship between the enhanced and non-contrast CT. VNC images were generated in the test through the trained U-Net. The CT values of non-contrast, enhanced and VNC CT images were compared. The radiotherapy treatment plans for esophageal cancer were designed, and dose calculation was performed. Dose distributions in the three image sets were compared. Results: The mean absolute error of CT values between enhanced and non-contrast CT reached 32.3 ± 2.6 HU, and that between VNC and non-contrast CT totaled 6.7 ± 1.3 HU. The average CT values in enhanced CT of great vessels, heart, lungs, liver, and spinal cord were all significantly higher than those of non-contrast CT (p < 0.05), with the differences reaching 97, 83, 42, 40, and 10 HU, respectively. The average CT values of the organs in VNC CT showed no significant differences from those in non-contrast CT. The relative dose differences of the enhanced and non-contrast CT were -1.2, -1.3, -2.1, and -1.5% in the comparison of mean doses of planned target volume, heart, great vessels, and lungs, respectively. The mean dose calculated by VNC CT showed no significant difference from that by non-contrast CT. The average γ passing rate (2%, 2 mm) of VNC CT image was significantly higher than that of enhanced CT image (0.996 vs. 0.973, p < 0.05). Conclusion: Designing a treatment plan based on enhanced CT will enlarge the dose calculation uncertainty in radiotherapy. This paper proposed the generation of VNC CT images from enhanced CT images based on U-Net architecture. The dose calculated through VNC CT images was identical with that obtained through real non-contrast CT.

2.
Mitochondrial DNA B Resour ; 4(2): 2757-2758, 2019 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-33365716

RESUMEN

Sarcophaga tuberosa has certain sanitary and epidemiological significance and takes proteins from decaying matter. In this study, we first sequenced and analyzed the complete mitochondrial genome (mitogenome) of S. tuberosa. The length of mitogenome was 15,173 bp, consisting of A (39.5%), G (9.4%), T (37.0%), and C (14.1%), and the order and orientation of genes were identical with that from the mittogenomes of flesh flies previously reported. Phylogenetic analyses showed that S. tuberosa was clustered separately, but which was closed to the species of Sarcophaga portschinskyi. This study provided better support for further understanding of phylogenetic relationships and enriched the mitogenome database of flesh flies.

3.
Herald of Medicine ; (12): 161-166, 2024.
Artículo en Zh | WPRIM | ID: wpr-1023693

RESUMEN

Objective To study the protective effect of Wedelolactone(WEL)against inflammatory injury in human umbilical vein endothelial cells(HUVECs)and its molecular mechanism by inducing PI3K/Akt/mTOR.Methods The model of atherosclerosis(AS)oxidative stress injury in HUVECs was induced with 200 μmol·L-1 of hydrogen peroxide for 24 h.The experimental groups were as follows:normal control group,DMSO(dimethyl sulfoxide)group,H2O2 group,and WEL group.MTT was used to measure the cell survival rate of each group;flow cytometry was used to assess intracellular ROS levels;fluorescence microscopy was used to detect the expression of p62 protein;immunoblotting assay was used to determine the protein expression levels for apoptosis-related proteins associated with PI3K/Akt/mTOR signaling pathway and autophagy-related proteins.Results Compared with the H2 O2 group,the HUVEC cell survival rate was significantly inhibited in the WEL group(P<0.05).ROS production was significantly lower,and the protein expressions of SOD1 and p62 were significantly increased in the WEL group as compared to the hydrogen peroxide group.The protein expression of p-mTOR,p-Akt,and p-PI3K was significantly decreased in hydrogen peroxide(P<0.01);In the WEL experiment,p-mTOR,p-Akt,and p-PI3K were increased significantly in the post-injury HUVECs(P<0.01).Conclusion Wedelolactone inhibits HUVECs'autophagy by suppressing H2O2-induced inflammatory damage in HUVECs,which may be related to the fact that WEL promotes the phosphorylation of PI3K,Akt,and mTOR proteins,inhibits autophagy and thus resists oxidative stress damage in HUVECs cells.

4.
Artículo en Zh | WPRIM | ID: wpr-1026189

RESUMEN

A dose reconstruction algorithm for electrionic portal imaging device(EPID)based on calibration and calculation is developed.The raw data of EPID in continuous acquisition mode are corrected for dark field and gain,and the gray level features of bright field are used to determine the field boundary.Subsequently,MU calibration,off-axis calibration and field size calibration are performed on the EPID data,and dose reconstruction is carried out based on the calibrated superimposed flux and the Monte Carlo model of the linac head.Nine cases of IMRT plans are selected for verification and measurement using EPID and MapCheck separately,and the passing rates between the two tools are compared under different gamma criteria(3%/3 mm and 2%/2 mm).For a planned case,the average passing rates of multiple cases verified by MapCheck under the two criteria were 99.02%±1.28%and 90.84%±4.49%,and the average passing rates of the EPID reconstruction models were 98.86%±1.19%and 91.39%±4.80%.Compared with MapCheck,the EPID reconstruction algorithm based on calibration and calculation has no significant difference in the passing rate of IMRT plan verification(P>0.05),which meets the clinical requirements of dose verification.

5.
Artículo en Zh | WPRIM | ID: wpr-1039029

RESUMEN

Alzheimer’s disease (AD) is a central neurodegenerative disease characterized by progressive cognitive dysfunction and behavioral impairment, and there is a lack of effective drugs to treat AD clinically. Existing medications for the treatment of AD, such as Tacrine, Donepezil, Rivastigmine, and Aducanumab, only serve to delay symptoms and but not cure disease. To add insult to injury, these medications are associated with very serious adverse effects. Therefore, it is urgent to explore effective therapeutic drugs for AD. Recently, studies have shown that a variety of enzyme inhibitors, such as cholinesterase inhibitors, monoamine oxidase (MAO)inhibitors, secretase inhibitors, can ameliorate cholinergic system dysfunction, Aβ production and deposition, Tau protein hyperphosphorylation, oxidative stress damage, and the decline of synaptic plasticity, thereby improving AD symptoms and cognitive function. Some plant extracts from natural sources, such as Umbelliferone, Aaptamine, Medha Plus, have the ability to inhibit cholinesterase activity and act to improve learning and cognition. Isochromanone derivatives incorporating the donepezil pharmacophore bind to the catalytic active site (CAS) and peripheral anionic site (PAS) sites of acetylcholinesterase (AChE), which can inhibit AChE activity and ameliorate cholinergic system disorders. A compound called Rosmarinic acid which is found in the Lamiaceae can inhibit monoamine oxidase, increase monoamine levels in the brain, and reduce Aβ deposition. Compounds obtained by hybridization of coumarin derivatives and hydroxypyridinones can inhibit MAO-B activity and attenuate oxidative stress damage. Quinoline derivatives which inhibit the activation of AChE and MAO-B can reduce Aβ burden and promote learning and memory of mice. The compound derived from the combination of propargyl and tacrine retains the inhibitory capacity of tacrine towards cholinesterase, and also inhibits the activity of MAO by binding to the FAD cofactor of monoamine oxidase. A series of hybrids, obtained by an amide linker of chromone in combine with the benzylpiperidine moieties of donepezil, have a favorable safety profile of both cholinesterase and monoamine oxidase inhibitory activity. Single domain antibodies (such as AAV-VHH) targeted the inhibition of BACE1 can reduce Aβ production and deposition as well as the levels of inflammatory cells, which ultimately improve synaptic plasticity. 3-O-trans-p-coumaroyl maslinic acid from the extract of Ligustrum lucidum can specifically inhibit the activity of γ-secretase, thereby rescuing the long-term potentiation and enhancing synaptic plasticity in APP/PS1 mice. Inhibiting γ-secretase activity which leads to the decline of inflammatory factors (such as IFN-γ, IL-8) not only directly improves the pathology of AD, but also reduces Aβ production. Melatonin reduces the transcriptional expression of GSK-3β mRNA, thereby decreasing the levels of GSK-3β and reducing the phosphorylation induced by GSK-3β. Hydrogen sulfide can inhibitGSK-3β activity via sulfhydration of the Cys218 site of GSK-3β, resulting in the suppression of Tau protein hyperphosphorylation, which ameliorate the motor deficits and cognitive impairment in mice with AD. This article reviews enzyme inhibitors and conformational optimization of enzyme inhibitors targeting the regulation of cholinesterase, monoamine oxidase, secretase, and GSK-3β. We are hoping to provide a comprehensive overview of drug development in the enzyme inhibitors, which may be useful in treating AD.

6.
Artículo en Zh | WPRIM | ID: wpr-1003568

RESUMEN

In the current clinical diagnosis, medical images have become an important basis for diagnosis, and different modes of medical images provide different tissue information and functional information. Single-mode images can only provide single diagnostic information, by which difficult and complicated diseases cannot be diagnosed, and comprehensive and accurate diagnostic results can be obtained only with the help of multiple diagnostic information. The multimodal fusion technology fuses multiple modes of medical images into single-mode images, and thus the single-mode images contain complementary information between multiple modes of images, so that sufficient information for clinical diagnosis can be obtained in a single image. In this paper, the multimodal medical image fusion methods are sorted into two types, namely the traditional fusion method and the fusion method based on deep learning.

7.
Artículo en Zh | WPRIM | ID: wpr-993165

RESUMEN

Objective:To develop the real-time radiotherapy monitoring system of three-dimensional (3D) point cloud by using depth camera and verify its feasibility.Methods:Taking the depth camera coordinate system as the world coordinate system, the conversion relationship between the simulation CT coordinate system and the world coordinate system was obtained from the calibration module. The patient's simulation CT point cloud was transformed into the world coordinate system through the above relationship, and registered with the patient's surface point cloud obtained in real-time manner by the depth camera to calculate the six-dimensional (6D) error, and complete the positioning verification and fractional internal position error monitoring in radiotherapy. Mean and standard deviation of 6D calculation error, Hausdorff distance of point cloud after registration and the running time of each part of the program were calculated to verify the feasibility of the system. Fifteen real patients were selected to calculate the 6D error between the system and cone beam CT (CBCT).Results:In the phantom experiment, the errors of the system in the x, y and z axes were (1.292±0.880)mm, (1.963±1.115)mm, (1.496±1.045)mm, respectively, and the errors in the rotation, pitch and roll directions were 0.201°±0.181°, 0.286°±0.326°, 0.181°±0.192°, respectively. For real patients, the translational error of the system was within 2.6 mm, the rotational error was approximately 1°, and the program run at 1-2 frames/s. The precision and speed met the radiotherapy requirement. Conclusion:The 3D point cloud radiotherapy real-time monitoring system based on depth camera can automatically complete the positioning verification before radiotherapy, real-time monitoring of body position during radiotherapy, and provide error visual feedback, which has potential clinical application value.

8.
Artículo en Zh | WPRIM | ID: wpr-1027422

RESUMEN

Objective:To construct a cycle dual-task network based on cycleGAN to implement 3D CT synthesis from single-view projection for adaptive radiotherapy of thoracic tumor and then evaluate image quality and dose accuracy.Methods:A total of 45 thoracic tumor patients admitted to the Affiliated Changzhou No.2 People's Hospital of Nanjing Medical University were collected, and 991 cases were also selected from public dataset as pretrained dataset. Multi-view projections were acquired by ASTRA algorithm. The public dataset was divided into a training set of 800 cases, a validation set of 160 cases and a test set of 31 cases. The dataset obtained from patients in our hospital was divided into a training set of 40 cases and a test set of 5 cases. The network included synthetic CT model and multi-view projection prediction model and achieved the dual-task training. The final test only used the synthetic CT model to acquire the predicted CT images and deliver image quality [mean absolute error (MAE), peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM)] and dose evaluation.Results:Image quality evaluation metrics for synthetic CT showed high image synthesis accuracy with MAE of 0.05±0.01, PSNR of 19.08±1.69, SSIM of 0.75±0.04, respectively. The dose distribution calculated on synthetic CT was also close to the actual dose distribution. The mean 3%/3 mm γ pass rate for synthetic CT was 93.1%.Conclusions:A dual-task cycle network modified on cycleGAN has been implemented to rapidly and accurately predict 3D CT from single-view projection, which can be applied to the workflow of adaptive radiotherapy for thoracic cancer. Both image generation quality and dosimetric evaluation demonstrate that synthetic CT can meet the clinical requirements for radiotherapy.

9.
Asian Journal of Andrology ; (6): 719-724, 2023.
Artículo en Inglés | WPRIM | ID: wpr-1009785

RESUMEN

Long-segment lichen sclerosus (LS) urethral stricture is a challenge for urologists. Limited data are available for surgeons to make a surgical decision between Kulkarni and Asopa urethroplasty. In this retrospective study, we investigated the outcomes of these two procedures in patients with LS urethral stricture. Between January 2015 and December 2020, 77 patients with LS urethral stricture underwent Kulkarni and Asopa procedures for urethroplasty in the Department of Urology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine (Shanghai, China). Of the 77 patients, 42 (54.5%) underwent the Asopa procedure and 35 (45.5%) underwent the Kulkarni procedure. The overall complication rate was 34.2% in the Kulkarni group and 19.0% in the Asopa group, and no difference was observed ( P = 0.105). Among the complications, no statistical difference was observed in the incidence of urethral stricture recurrence ( P = 0.724) or glans dehiscence ( P = 0.246) except for postoperative meatus stenosis ( P = 0.020). However, the recurrence-free survival rate between the two procedures was significantly different ( P = 0.016). Cox survival analysis showed that antiplatelet/anticoagulant therapy use ( P = 0.020), diabetes ( P = 0.003), current/former smoking ( P = 0.019), coronary heart disease ( P < 0.001), and stricture length ( P = 0.028) may lead to a higher hazard ratio of complications. Even so, these two techniques can still provide acceptable results with their own advantages in the surgical treatment of LS urethral strictures. The surgical alternative should be considered comprehensively according to the patient characteristics and surgeon preferences. Moreover, our results showed that antiplatelet/anticoagulant therapy use, diabetes, coronary heart disease, current/former smoking, and stricture length may be contributing factors of complications. Therefore, patients with LS are advised to undergo early interventions for better therapeutic effects.


Asunto(s)
Masculino , Humanos , Estrechez Uretral/etiología , Estudios Retrospectivos , Constricción Patológica/cirugía , Liquen Escleroso y Atrófico/cirugía , Resultado del Tratamiento , Procedimientos Quirúrgicos Urológicos Masculinos/métodos , China , Uretra/cirugía , Complicaciones Posoperatorias/etiología , Mucosa Bucal , Diabetes Mellitus/etiología , Anticoagulantes , Enfermedad Coronaria
10.
Asian Journal of Andrology ; (6): 294-298, 2022.
Artículo en Inglés | WPRIM | ID: wpr-928557

RESUMEN

General recommendations regarding surgical techniques are not always appropriate for all Peyronie's disease (PD) patients. Therefore, the purpose of this study was to investigate the effects of plication procedures in PD patients with severe penile curvature and the effects of early surgical correction in patients who no longer have progressive deformities. The clinical data from 72 patients who underwent plication procedures were analyzed in this study. Patients were divided into Groups A and B according to the curvature severity (≤60° or >60°) and Groups 1 and 2 according to the duration of disease stabilization (≥3 months or <3 months). At the 1-year follow-up, 90.0% (36/40) and 90.6% (29/32) patients reported complete penile straightening, and 60.0% (24/40) and 100.0% (32/32) patients reported penile shortening in Groups A and B, respectively. No curvature recurrence occurred in any patient, and no significant differences were observed in postoperative International Index of Erectile Function-Erectile Function domain (IIEF-EF), erectile pain, sensitivity, or suture knots on the penis whether such outcomes were grouped according to the curvature severity or the duration of stabilization. However, the duration from symptom onset to surgical management in Group 1 was significantly longer than that in Group 2 (mean ± standard deviation [s.d.]: 20.9 ± 2.0 months and 14.3 ± 1.2 months, respectively, P < 0.001). The present study showed that the plication procedures seemed to be an effective choice for the surgical treatment of PD patients with severe penile curvature. In addition, the early surgical treatment seemed to benefit those patients who already had no erectile pain and no longer exhibited progressive deformity.


Asunto(s)
Humanos , Masculino , Disfunción Eréctil/cirugía , Satisfacción del Paciente , Dolor Pélvico , Induración Peniana/cirugía , Pene/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
11.
Chinese Journal of Trauma ; (12): 136-141, 2022.
Artículo en Zh | WPRIM | ID: wpr-932218

RESUMEN

Objective:To investigate the clinical effect of combined treatment of comminuted inferior pole patellar fracture with micro-plate and tension-band wire.Methods:A retrospective cohort study was conducted in 50 patients with comminuted inferior pole patellar fracture (AO classification of type 34-A1) admitted to First Affiliated Hospital of University of Science and Technology of China from October 2018 to October 2020, including 28 males and 22 females, aged 17-77 years[(51.4±11.5)years]. A total of 23 patients were treated with micro-plate combined with tension-band wire (Group A) and 27 patients were treated with cable wire looping combined with tension-band wire (Group B). Fracture union, union time and last follow-up evaluation of knee range of motion and Bostman score were compared between the two groups. Complications (infection, internal fixation failure, internal fixation irritation, etc.) were also observed.Results:All patients were followed up for 12-18 months[(14.1±2.1) months]. All patients had bone union, with no statistical difference between Group A[(9.9±1.8)weeks]and Group B[(10.3±1.4)weeks]in union time ( P>0.05). Knee range of motion was (129.2±9.7)° in Group A at the last follow-up, better than (122.3±11.0)° in Group B ( P<0.05). Knee Bostman score was (27.6±1.8)points in Group A, showing no statistical difference from that in Group B[(26.8±1.9)points]( P>0.05). There were no postoperative complications in Group A. Two patients with tension band shedding of Kirschner wire after fracture healing were found in Group B, with no special treatment given due to no obvious discomfort. Conclusions:For comminuted inferior pole patellar fracture, micro-plate combined with tension-band wire is more effective and provides better knee mobility with no complications of implant failure as compared with cable wire looping combined with tension-band wire. Therefore, the technique deserves clinical promotion.

12.
Journal of Forensic Medicine ; (6): 601-605, 2022.
Artículo en Inglés | WPRIM | ID: wpr-984153

RESUMEN

OBJECTIVES@#To establish a carbofuran intragastric administration death model in rabbits, and to observe the postmortem distribution and postmortem redistribution of carbofuran-7-phenyl glucuronic acid (Glu-7PH) in rabbits.@*METHODS@#The postmortem distribution: Rabbits were given an administration of 1/2LD50, LD50, 2LD50 carbofuran. Dead rabbits were dissected immediately. Rabbits that had remained alive 2 hours were sacrificed by carbon dioxide (CO2) inhalation and dissected immediately. The myocardium, cardiac blood, liver, spleen, lung, kidney, brain and right hindlimb muscle were collected. The postmortem redistribution: After giving an administration of 4LD50 carbofuran, the myocardium, cardiac blood, liver, spleen, lung, kidney, brain, and right hindlimb muscle were collected at 0, 12, 24, 48, and 72 h postmortem in supine position at 15 ℃ room temperature. The quantity of Glu-7PH was determined by LC-MS/MS.@*RESULTS@#The postmortem distribution: Among the three dose groups, there were significant differences in the quantities of Glu-7PH in different tissues. The postmortem redistribution: There was no significant difference in the Glu-7PH quantities in cardiac blood, mycardium, spleen, kidney, brain and right hindlimb muscle, but there was a significant difference in the Glu-7PH quantities in the liver and lung.@*CONCLUSIONS@#The mycardium, cardiac blood, liver, lung, kidney, brain and hindlimb muscle of rabbits can be used as appropriate samples for Glu-7PH detection. However, it should be noted that Glu-7PH was redistributed postmortem in rabbit liver and lung.


Asunto(s)
Animales , Conejos , Carbofurano , Cromatografía Liquida , Cambios Post Mortem , Espectrometría de Masas en Tándem , Autopsia
13.
Artículo en Zh | WPRIM | ID: wpr-965551

RESUMEN

@#<b>Objective</b> To investigate the dosimetric effect of truncated regions in computed tomography (CT) images on the targets and organs at risk in volumetric modulated arc therapy (VMAT) for middle thoracic esophageal cancer. <b>Methods</b> CT images of 15 patients with middle thoracic esophageal cancer were selected. Circle masks were used to make the volume of the truncated region account for 10%, 20%, 30%, and 40% of the arm volume, and the corresponding truncated CT images were obtained. The real CT was denoted as CT0. Two radiotherapy plans were made on CT0. One plan was VMAT_1F with full arcs, and the other one was VMAT_3F with arm avoidance. The plans were transplanted to four truncated CT, respectively, and the dosimetric differences between different plans were compared using Wilcoxon signed-rank test. <b>Results</b> Compared with VMAT_1F in CT0, <i>D</i><sub>mean</sub> and <i>V</i><sub>5</sub> of the lung decreased in VMAT_3F, but <i>D</i><sub>max</sub> of the spinal cord, <i>D</i><sub>mean</sub> of the heart, and <i>V</i><sub>20</sub> of the lung increased. In VMAT_3F, there was no statistically significant difference between the dosimetric parameters in the four truncated CT and those in CT0 (all <i>P</i> > 0.05). In VMAT_1F, except for homogeneity index and <i>D</i><sub>max</sub> of the spinal cord, the dosimetric parameters in four truncated CT were significantly different from those in CT0 (<i>P</i> < 0.05). The dosimetric difference increased with the increase in truncated region-to-volume ratio. <b>Conclusion</b> Complete CT data should be collected in clinical practice, and the radiation field avoiding the truncated regionshould be set if necessary to reduce the influence of the truncated region on dosimetry.

14.
Artículo en Zh | WPRIM | ID: wpr-974383

RESUMEN

Medical images can provide clinicans with accurate and comprehensive patients’ information. Morphological or functional abnormalities caused by various diseases can be manifested in many aspects. Although MR images and CT images can highlight the medical image data of different tissue structures of patients, single MR images or CT images cannot fully reflect the complexity of diseases. Using MR image to predict CT image is one of the cross-modal prediction of medical images. In this paper, the methods of MR image prediction for CTmage are classified into four categoriesincluding registration based on atlas, based on image segmentationmethod, based on learning method and based on deep learning method. In our research, we concluded that the method based on deep learning should bemore promoted in the future by compering the existing problems and future development of MR image predicting CT image method.

15.
Asian Journal of Andrology ; (6): 484-489, 2021.
Artículo en Inglés | WPRIM | ID: wpr-888460

RESUMEN

Surgical correction can be considered for treating patients with a chronic phase of Peyronie's disease (PD) and persistent penile curvature. In clinical practice, some patients pay too much attention to surgical complications and refuse the recommended feasible surgical types. Meanwhile, they require operations according to their preferences. This study aimed to evaluate the effects of patients' own choice of surgical type on postoperative satisfaction. This retrospective study analyzed data from 108 patients with PD who underwent surgical correction according to doctors' recommendations or patients' own demands. The objective and subjective surgical outcomes were assessed. Patients' understanding of the disease was analyzed using a questionnaire survey. Objective measurements of surgical outcomes, including penile straightening, penile length, and sexual function, in patients who received the recommended surgery, were similar to those in patients who did not accept the recommended surgery. However, subjective evaluations, including erectile pain, discomfort because of nodules on the penis, and decreased sensitivity in the penis, were more obvious in patients who did not follow doctors' recommendations. In addition, a questionnaire survey showed that understanding PD and the purpose of surgery of patients who did not follow doctors' advice were inappropriate, as they did not conform to the principle of treatment. The present study showed that surgical correction seemed to be an objectively effective option in the management of patients in the stable chronic phase of PD. Low patient satisfaction might be related to patients' lack of correct understanding of the disease and its treatment strategy as well as unrealistic expectations.

16.
Artículo en Zh | WPRIM | ID: wpr-910345

RESUMEN

Objective:To develop a 3D visualization technology-assisted patient positioning system for radiotherapy and compare it with traditional patient positioning method for breast and pelvic radiotherapy.Methods:A total of 40 patients receiving radiotherapy in Changzhou No.2 People′s Hospital from June 2020 to April 2021 were selected for this study, including 20 patients with breast cancer and 20 patients with pelvic cancer.3D visualization reconstruction was carried out using the CT data of the patients for positioning. Then the 3D visualization models were integrated with the real treatment environment and were then shifted to the isocentral positions of accelerators through interactive operations. Based on this, the patients were actually positioned. Every week, all of the patients were firstly treated with traditional positioning, followed by 3D visualization-guided positioning. As a result, 240 times of positioning data of all patients were collected in three weeks. They were compared with the data of cone-beam CT(CBCT)-guided positioning, which served as the gold standard.Results:The absolute positioning errors of 3D visualization-guided positioning along x, y and z axes were (1.92±1.23), (2.04±1.16), and (1.77±1.37)mm, respectively for patients with breast cancer and were (2.07±1.08), (1.33±0.88), and (1.99±1.25)mm, respectively for patients with pelvic cancer. Compared with traditional positioning method , the accuracy of 3D visualization-guided positioning along x、 y, and z axes was increased by 38.83%, 52.40% and 33%, respectively for patients with breast cancer and was improved by 36.84%, 54.04% and 52.58% for patients with pelvic cancer, with all differences being statistically significant along y and z axes ( t=2.956-5.734, P< 0.05). Meanwhile, the error distribution of the two positioning method was statistically significant along in y axis for patients with breast cancer( χ2=7.481, P<0.05) and was statistically significant along each axis for patients with pelvic cancer( χ2=5.900, 6.415, 7.200, P<0.05). Conclusions:The positioning method guided by 3D visualization technology can effectively improve the positioning accuracy of patients with breast cancer and patients with pelvic cancer and is of value in potential clinical application.

17.
Artículo en Zh | WPRIM | ID: wpr-910553

RESUMEN

Objective:To explore the volume resolution of prostate motion target by four-dimensional (4D) ultrasound.Methods:The prostate ultrasound model was selected, and the group comparison study was conducted using 4D ultrasound to outline the prostate target under different motion amplitudes (A) and motion period (T). The simulated A value was set as 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, and 5 mm, respectively. The T value was set as 1 s, 2 s, 3 s, and 4 s, respectively. The volume of the target of the model prostate was calculated, and the static ultrasound image of the target was used as the control group to analyze the difference between two groups.Results:When the model was still, the size of the target of ultrasound was consistent with that of CT scan ( P>0.05). When the A values were 0.5 mm and 1 mm, there was no statistical difference between the volume in period 1-4 s and the volume in the target at rest (all P>0.05). When the A values were 2 mm and 3 mm, and the T values were 1 s, 2 s and 3 s there was statistical difference between the volume of target and that of of static ultrasonic target (all P<0.05). When the A value was 2 mm and the T value was 4 s, there was no statistical difference between the target volume and the static target volume ( P=0.710). The range within the group was 6.7 cm 3, and the standard deviation was 1.15 cm 3. When the A value was 3 mm and the T value was 4 s, the volume repeatability of the target was poor, and the range within the group was 14.4 cm 3; when the A values were 4 mm and 5 mm, and the T values were 1-4 s, the range within the group was 3.27-17.63 cm 3 and 6.51-21.02 cm 3, respectively. The volume repeatability of the target under each period was extremely poor, which could not meet the clinical requirements. Conclusion:4D ultrasound can provide reliable reference data for patients′ target delineation within 1-4 s of motion cycle and within 1 mm of motion amplitude, which exerts on effect upon the original position of probe.

18.
Eur J Radiol ; 55(1): 139-45, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15950111

RESUMEN

INTRODUCTION: With the promotion and application of digital imaging technology in the medical domain, the amount of medical images has grown rapidly. However, the commonly used compression methods cannot acquire satisfying results. METHODS: In this paper, according to the existed and stated experiments and conclusions, the lifting step approach is used for wavelet decomposition. The physical and anatomic structure of human vision is combined and the contrast sensitivity function (CSF) is introduced as the main research issue in human vision system (HVS), and then the main designing points of HVS model are presented. On the basis of multi-resolution analyses of wavelet transform, the paper applies HVS including the CSF characteristics to the inner correlation-removed transform and quantization in image and proposes a new HVS-based medical image compression model. RESULTS: The experiments are done on the medical images including computed tomography (CT) and magnetic resonance imaging (MRI). At the same bit rate, the performance of SPIHT, with respect to the PSNR metric, is significantly higher than that of our algorithm. But the visual quality of the SPIHT-compressed image is roughly the same as that of the image compressed with our approach. Our algorithm obtains the same visual quality at lower bit rates and the coding/decoding time is less than that of SPIHT. CONCLUSIONS: The results show that under common objective conditions, our compression algorithm can achieve better subjective visual quality, and performs better than that of SPIHT in the aspects of compression ratios and coding/decoding time.


Asunto(s)
Algoritmos , Compresión de Datos/métodos , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Percepción Visual , Humanos , Variaciones Dependientes del Observador , Psicofísica
19.
China Pharmacy ; (12): 1272-1276, 2020.
Artículo en Zh | WPRIM | ID: wpr-821619

RESUMEN

OBJECTIVE:To investiga te the role of clinical pharmacists in drug therapy for patients with severe pemphigus. METHODS:Clinical pharmacists participated in drug therapy for a patient with severe pemphigus. Clinical pharmacist adjusted the doctor’s medication plan in time according to the symptoms and adverse reactions of the patients. In view of several new blisters on the hand palms and back that may be caused by hormone reduction ,the clinical pharmacist suggested that the dosage of Prednisone acetate tablets should be adjusted to 70 mg before administration ,once a day. For poor infection control ,it was recommended to adjust the dose of minocycline to 100 mg,bid;for hypokalemia ,the clinical pharmacist advised the patients to take potassium orally,and added it into juice ,milk or honey for taking ;in order to prevent osteoporosis caused by glucocorticoid ,the clinical pharmacist suggested that patients supplement Calcium carbonate and vitamin D 3 chewable tablets and Alendronate sodium and vitamin D 3 tablets 70 mg at the same time ,once a week. For Candida albicans in patient ’s oral mucosa ,according to the results of drug sensitivity test ,the clinical pharmacists suggested that Itraconazole capsules should be adjusted to Fluconazole capsules 50 mg,once a day. At the same time ,pharmacist paid close attention to the adverse reactions after the infusion of Rituximab injection and pharmaceutical care was provided ,such as ADR monitoring ,discharge medication education. RESULTS :The doctors took all the advice of clinical pharmacists. The patient recovered and was discharged 47 days later. CONCLUSIONS :During drug therapy for the patient with severe pemphigus. Clinical pharmacists can help doctors improve the treatment plan so as to ensure the effectiveness and safety of patients ’medication.

20.
Journal of Medical Biomechanics ; (6): E364-E371, 2020.
Artículo en Zh | WPRIM | ID: wpr-862393

RESUMEN

Objective To study the relationship of the tibial plateau subchondral trabecular bone (STB) microstructure and the cartilage degeneration with the lower limb alignment based on individual trabecula segmentation (ITS) and histology analysis in knee osteoarthritis (OA). Methods Hip-knee-ankle (HKA) angles were measured on the full-length lower extremity films of patients before total knee arthroplasty (TKA). The tibial plateau excised from the TKA were collected for micro-CT scanning and ITS analysis. The cartilage degeneration was evaluated by histology. The relationship between the HKA angle and the changes in microstructural parameters of STB and cartilage degeneration were analyzed. ResultsThe plate, rod and axial bone trabecular volume fraction (BV/TV, pBV/TV, pBV/TV), ratio of trabecular plate versus rod (P/R), plate trabecular number density (pTb.N), plate trabecular thickness (pTb.Th), trabecular plate surface area (pTb.S), trabecular rod length (rTb.L), and plate-plate and plate-rod junction density (P-P Junc.D, P-R Junc.D) of the subchondral bone of the tibial plateau were significantly related to the cartilage degeneration OARSI score and the HKA angle. The greater the deviation of the lower limb alignment, the greater the number of subchondral trabeculae, the thicker the trabeculae, the greater the bone mass, the stronger the connectivity, especially the plate trabeculae on the affected side of tibial plateau, and the higher the OARSI score of cartilage degeneration. Conclusions Abnormal lower limb alignment may cause abnormal microstructure of the plate and rod STB of the tibial plateau by changing the stress distribution of the knee, especially the significant increase and thickening of the plate trabecular and axial trabecular bone, which may be an important risk factor that further aggravates the degeneration of articular cartilage and the progress of OA. Therefore, lower limb alignment correction with surgical intervention and improving STB with bone metabolism agents may efficiently contribute to preventing cartilage damage and mitigate OA progression.

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