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1.
Journal of Southern Medical University ; (12): 985-993, 2023.
Article in Chinese | WPRIM | ID: wpr-987012

ABSTRACT

OBJECTIVE@#To propose a tissue- aware contrast enhancement network (T- ACEnet) for CT image enhancement and validate its accuracy in CT image organ segmentation tasks.@*METHODS@#The original CT images were mapped to generate low dynamic grayscale images with lung and soft tissue window contrasts, and the supervised sub-network learned to recognize the optimal window width and level setting of the lung and abdominal soft tissues via the lung mask. The self-supervised sub-network then used the extreme value suppression loss function to preserve more organ edge structure information. The images generated by the T-ACEnet were fed into the segmentation network to segment multiple abdominal organs.@*RESULTS@#The images obtained by T-ACEnet were capable of providing more window setting information in a single image, which allowed the physicians to conduct preliminary screening of the lesions. Compared with the suboptimal methods, T-ACE images achieved improvements by 0.51, 0.26, 0.10, and 14.14 in SSIM, QABF, VIFF, and PSNR metrics, respectively, with a reduced MSE by an order of magnitude. When T-ACE images were used as input for segmentation networks, the organ segmentation accuracy could be effectively improved without changing the model as compared with the original CT images. All the 5 segmentation quantitative indices were improved, with the maximum improvement of 4.16%.@*CONCLUSION@#The T-ACEnet can perceptually improve the contrast of organ tissues and provide more comprehensive and continuous diagnostic information, and the T-ACE images generated using this method can significantly improve the performance of organ segmentation tasks.


Subject(s)
Learning , Image Enhancement , Tomography, X-Ray Computed
2.
Journal of Southern Medical University ; (12): 620-630, 2023.
Article in Chinese | WPRIM | ID: wpr-986970

ABSTRACT

OBJECTIVE@#To propose a semi-supervised material quantitative intelligent imaging algorithm based on prior information perception learning (SLMD-Net) to improve the quality and precision of spectral CT imaging.@*METHODS@#The algorithm includes a supervised and a self- supervised submodule. In the supervised submodule, the mapping relationship between low and high signal-to-noise ratio (SNR) data was constructed through mean square error loss function learning based on a small labeled dataset. In the self- supervised sub-module, an image recovery model was utilized to construct the loss function incorporating the prior information from a large unlabeled low SNR basic material image dataset, and the total variation (TV) model was used to to characterize the prior information of the images. The two submodules were combined to form the SLMD-Net method, and pre-clinical simulation data were used to validate the feasibility and effectiveness of the algorithm.@*RESULTS@#Compared with the traditional model-driven quantitative imaging methods (FBP-DI, PWLS-PCG, and E3DTV), data-driven supervised-learning-based quantitative imaging methods (SUMD-Net and BFCNN), a material quantitative imaging method based on unsupervised learning (UNTV-Net) and semi-supervised learning-based cycle consistent generative adversarial network (Semi-CycleGAN), the proposed SLMD-Net method had better performance in both visual and quantitative assessments. For quantitative imaging of water and bone materials, the SLMD-Net method had the highest PSNR index (31.82 and 29.06), the highest FSIM index (0.95 and 0.90), and the lowest RMSE index (0.03 and 0.02), respectively) and achieved significantly higher image quality scores than the other 7 material decomposition methods (P < 0.05). The material quantitative imaging performance of SLMD-Net was close to that of the supervised network SUMD-Net trained with labeled data with a doubled size.@*CONCLUSIONS@#A small labeled dataset and a large unlabeled low SNR material image dataset can be fully used to suppress noise amplification and artifacts in basic material decomposition in spectral CT and reduce the dependence on labeled data-driven network, which considers more realistic scenario in clinics.


Subject(s)
Tomography, X-Ray Computed/methods , Image Processing, Computer-Assisted/methods , Algorithms , Signal-To-Noise Ratio , Perception
3.
Journal of Southern Medical University ; (12): 88-92, 2019.
Article in Chinese | WPRIM | ID: wpr-772116

ABSTRACT

OBJECTIVE@#To develop a deep features-based model to classify benign and malignant breast lesions on full- filed digital mammography.@*METHODS@#The data of full-filed digital mammography in both craniocaudal view and mediolateral oblique view from 106 patients with breast neoplasms were analyzed. Twenty-three handcrafted features (HCF) were extracted from the images of the breast tumors and a suitable feature set of HCF was selected using -test. The deep features (DF) were extracted from the 3 pre-trained deep learning models, namely AlexNet, VGG16 and GoogLeNet. With abundant breast tumor information from the craniocaudal view and mediolateral oblique view, we combined the two extracted features (DF and HCF) as the two-view features. A multi-classifier model was finally constructed based on the combined HCF and DF sets. The classification ability of different deep learning networks was evaluated.@*RESULTS@#Quantitative evaluation results showed that the proposed HCF+DF model outperformed HCF model, and AlexNet produced the best performances among the 3 deep learning models.@*CONCLUSIONS@#The proposed model that combines DF and HCF sets of breast tumors can effectively distinguish benign and malignant breast lesions on full-filed digital mammography.


Subject(s)
Female , Humans , Breast Neoplasms , Classification , Diagnostic Imaging , Deep Learning , Diagnosis, Computer-Assisted , Methods , Mammography , Methods
4.
Journal of Southern Medical University ; (12): 192-200, 2019.
Article in Chinese | WPRIM | ID: wpr-772099

ABSTRACT

OBJECTIVE@#To develop a digital breast tomosynthesis (DBT) imaging system with optimizes imaging chain.@*METHODS@#Based on 3D tomography and DBT imaging scanning, we analyzed the methods for projection data correction, geometric correction, projection enhancement, filter modulation, and image reconstruction, and established a hardware testing platform. In the experiment, the standard ACR phantom and high-resolution phantom were used to evaluate the system stability and noise level. The patient projection data of commercial equipment was used to test the effect of the imaging algorithm.@*RESULTS@#In the high-resolution phantom study, the line pairs were clear without confusing artifacts in the images reconstructed with the geometric correction parameters. In ACR phantom study, the calcified foci, cysts, and fibrous structures were more clearly defined in the reconstructed images after filtering and modulation. The patient data study showed a high contrast between tissues, and the lesions were more clearly displayed in the reconstructed image.@*CONCLUSIONS@#This DBT imaging system can be used for mammary tomography with an image quality comparable to that of commercial DBT systems to facilitate imaging diagnosis of breast diseases.


Subject(s)
Female , Humans , Algorithms , Artifacts , Breast , Diagnostic Imaging , Mammography , Methods , Phantoms, Imaging , Radiographic Image Enhancement , Methods
5.
Journal of Medical Postgraduates ; (12): 714-718, 2018.
Article in Chinese | WPRIM | ID: wpr-818049

ABSTRACT

Objective The aim of this study was to explore the regulatory effect of calcitonin gene-related peptide (CGRP) on nitric oxide synthase (NOS) and the nitric oxide (NO) pathway in tibial fracture (TF) healing in the rat model of highly selective denervation.Methods A total of 60 SD rats were randomly divided into three groups of equal number, TF control, TF + sensory denervation (SD), and TF + motor denervation (MD). At 1, 2, 3 and 4 weeks after modeling, osteotylus samples were obtained from the rats for observation of the bone morphology and determination of the expressions of CGRP and NOS by immunohistochemistry and HE staining.Results At 2 and 3 weeks after modeling, the rats of the TF+SD group, as compared with the TF controls, showed significantly decreased expression of CGRP (0.150±0.014 vs 0.210±0.013, P<0.05; 0.143±0.017 vs 0.203±0.013, P<0.05) and that of eNOS in the osteotylus (0.170±0.016 vs 0.219±0.026, P<0.05; 0.158±0.016 vs 0.201±0.013, P<0.05).Conclusion Selective denervation, especially sensory denervation, may change the expression of CGRP and thereby that of NOS in the osteotylus of the rat with tibial fracture, which consequently affects the growth of the osteotylus and fracture healing as well.

6.
Journal of Southern Medical University ; (12): 1331-1337, 2018.
Article in Chinese | WPRIM | ID: wpr-771472

ABSTRACT

OBJECTIVE@#To establish a cone beam computed tomography (ECBCT) system for high-resolution imaging of the extremities.@*METHODS@#Based on three-dimensional X-Ray CT imaging and high-resolution flat plate detector technique, we constructed a physical model and a geometric model for ECBCT imaging, optimized the geometric calibration and image reconstruction methods, and established the scanner system. In the experiments, the pencil vase phantom, image quality (IQ) phantom and a swine feet were scanned using this imaging system to evaluate its effectiveness and stability.@*RESULTS@#On the reconstructed image of the pencil vase phantom, the edges were well preserved with geometric calibrated parameters and no aliasing artifacts were observed. The reconstructed images of the IQ phantom showed a uniform distribution of the CT number, and the noise power spectra were stable in multiple scanning under the same condition. The reconstructed images of the swine feet had clearly displayed the bones with a good resolution.@*CONCLUSIONS@#The ECBCT system can be used for highresolution imaging of the extremities to provide important imaging information to assist in the diagnosis of bone diseases.


Subject(s)
Animals , Algorithms , Artifacts , Calibration , Cone-Beam Computed Tomography , Methods , Equipment Design , Extremities , Diagnostic Imaging , Image Processing, Computer-Assisted , Methods , Phantoms, Imaging , Radiographic Image Enhancement , Methods , Swine
7.
Journal of Zhejiang University. Science. B ; (12): 390-399, 2018.
Article in English | WPRIM | ID: wpr-772775

ABSTRACT

A rapid decline in egg production of laying hens begins after 480 d of age. Such a rapid decrease results predominantly from the ovarian aging, accompanied by endocrine changes, decreased yolk synthesis and accumulation, and the reduction in follicles selected into the preovulatory hierarchy. In this study, hens at 90, 150, 280, and 580 d old (D90, D150, D280, and D580, respectively) were compared for yolk precursor formation in the liver to elucidate effects of aging on laying performance. The results showed that liver lipid synthesis increased remarkably in hens from D90 to D150, but decreased sharply at D580 as indicated by the changes in triglyceride (TG) levels. This result was consistent with the age-related changes of the laying performance. The levels of liver antioxidants and total antioxidant capacity decreased significantly in D580 hens and the methane dicarboxylic aldehyde in D580 hens was much higher than that at other stages. The serum 17β-estradiol level increased from D90 to D280, but decreased at D580 (P<0.05). The expression of estrogen receptor α and β mRNAs in the liver displayed similar changes to the serum 17β-estradiol in D580 hens. Expressions of the genes related to yolk precursor formation and enzymes responsible for fat acid synthesis were all decreased in D580 hens. These results indicated that decreased yolk precursor formation in the liver of the aged hens resulted from concomitant decreases of serum 17β-estradiol level, transcription levels of estrogen receptors and critical genes involved in yolk precursor synthesis, and liver antioxidant status.


Subject(s)
Animals , Female , Age Factors , Antioxidants , Metabolism , Chickens , Egg Yolk , Metabolism , Estradiol , Blood , Lipids , Liver , Metabolism , Oviposition , Receptors, Estrogen , Genetics
8.
Chinese Circulation Journal ; (12): 984-988, 2018.
Article in Chinese | WPRIM | ID: wpr-703914

ABSTRACT

Objectives: To investigate whether remote ischemic conditioning (RIC) applied to patients with ST-segment elevation myocardial infarction (STEMI) before percutaneous coronary intervention (PCI) could affect circulating miR-208b level or not. Methods:Patients diagnosed with STEMI undergoing PCI from January 2016 to July 2017 were enrolled from the Department of Cardiology, Affiliated Zhongshan Hospital of Dalian University.The patients were randomly allocated to two groups: (1) control group (n=25), PCI alone; (2) RIC group (n=50), PCI combined with RIC (three cycles of 5 min inflation and 5 min deflation of the right lower limb with blood pressure cuff performed before reperfusion). Serum miR-208b was measured before and immediately, at 24 h, and 48 h after PCI with real-time quantitative polymerase chain reaction. Results: The expression of miR-208b was significantly higher immediately post PCI than that before operation in the control group (84.1±9.0 vs 77.8±9.4; P=0.032), while it was significantly lower immediately post PCI than that before operationin RIC group (71.0±9.3 vs 77.4±8.8; P=0.028).miR-208b level was similar before PCI between the control and RIC groups (P=0.874), which was significantly reduced immediately post PCI in RIC group as compared with the control group (P=0.021).The peak value of creatine kinase isoenzyme (CK-MB) in the limb RIC group was significantly lower than that in the control group ([135.2±18.6] U/L vs [167.7±17.2] U/L; P=0.038).The area under the CK-MB curve of the RIC group was significantly smaller than that of the control group ([3 060.7±17.1] U/L vs [3 635.9±15.1] U/L); P=0.047]. The left ventricular ejection fraction (LVEF) in RIC group was significantly higher than that in the control group ([57.8±7.8]% vs [51.9±7.9]%; P=0.003) post PCI. The expression level of serum miR-208b was positively correlated with CK-MB AUC in RIC group (r=0.498, P<0.001). Conclusions: RIC of the lower limb prior to PCI could reduce miR-208b level and improve cardiac functionin STEMI patients.

9.
Chinese Journal of Infectious Diseases ; (12): 537-542, 2018.
Article in Chinese | WPRIM | ID: wpr-707249

ABSTRACT

Objective To screen the differential microRNA (miRNA ) in human immunodeficiency virus (HIV) related Burkitt lymphoma (BL) and diffuse large B cell lymphoma (DLBCL).Methods Five freshly frozen tissue samples of BL and 3 freshly frozen tissu samples of DLBCL ,19 paraffin specimens of BL and 15 paraffin specimens of DLBCL were collected from Shanghai Public Health Clinical Center . Agilent human miRNA microarrays were employed to detect the miRNA expressions in fresh frozen BL tissues and fresh frozen DLBCL tissues ,and to find out differential miRNA .SmartRNAplexTMmiRNA was employed to verify the expressions of crucial miRNA in BL formalin fixed and paraffin-embedded tissues and DLBCL FFPET .Bioinformatics methods were used to predict the target genes of the crucial miRNA .Results Compared with DLBCL group ,42 differential miRNA were detected in BL group . Among them ,28 miRNA were up-regulated and 14 miRNA were down-regulated in BL group .According to positive control in eukaryote and high-expression molecular contributing to the emergence of tumor ,5 crucial miRNA were selected from 28 up-regulated miRNA in BL group for validation .The result was consistent with that of Agilent human miRNA microarrays .Compared with the DLBCL group ,5 crucial miRNA were all up-regulated in BL ,which were miRNA-16-2-3p ,miRNA-20a-3p ,miRNA-130b-3p , miRNA-185-5p and miRNA-423-5p (t=2 .7151 ,2 .539 ,2 .750 ,4 .004 ,and 3 .625 ,respectively ,all P<0 .05).The corresponding target genes of miRNA-16-2-3p might be CTNND2 and RAD21 .The target genes of miRNA-20a-3p might mainly be DYRK1A and GPAM .The target genes of miRNA-130b-3p might mainly be IRF1 , DICER1 and PTEN .The target genes of miRNA-185-5p might mainly be VEGFA ,NFATC3 and SEC24C .The target genes of miRNA-423-5p might mainly be PA2G4 and PNKD . Conclusions There are significantly differentially expressed miRNA between BL and DLBCL tissues . These miRNA are expected to provide new molecular markers for diagnosis and differential diagnosis of BL and DLBCL .Potential target genes of crucial miRNA are related with cell survival , proliferation , differentiation ,apoptosis and carcinogenesis ,etc ,which may play important roles in the origination and progress of BL.

10.
Journal of Southern Medical University ; (12): 323-329, 2017.
Article in Chinese | WPRIM | ID: wpr-273766

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the effect of detector performance during digital breast tomography (DBT) projection data acquisition on reconstructed image quality.</p><p><b>METHODS</b>With reference to the traditional detector data correction method and the specific data acquisition pattern in DBT imaging, we utilized dark field correction, light field and its gain correction for processing the projection data collected by the detector. The reconstructed images were evaluated using iterative reconstruction method based on total generalized variation (TGV).</p><p><b>RESULTS</b>In physical breast phantom experiment, the proposed method resulted in a reduced Heel effect caused by nonuniform photon number. The reconstructed DBT images after correction showed obviously improved image quality especially in the details with a low contrast.</p><p><b>CONCLUSION</b>The dark field correction, light field and its gain correction process for DBT image reconstruction can improve the image quality.</p>

11.
Chinese Medical Journal ; (24): 717-721, 2017.
Article in English | WPRIM | ID: wpr-266921

ABSTRACT

<p><b>BACKGROUND</b>Dendritic cells are professional antigen-presenting cells found in an immature state in epithelia and interstitial space, where they capture antigens such as pathogens or damaged tissue. Matrix metallopeptidase 13 (MMP-13), a member of the collagenase subfamily, is involved in many different cellular processes and is expressed in murine bone marrow-derived dendritic cells (DCs). The function of MMP-13 in DCs is not well understood. Here, we investigated the effect of MMP-13 on DC maturation, apoptosis, and phagocytosis.</p><p><b>METHODS</b>Bone marrow-derived dendritic cells were obtained from C57BL/6 mice. One short-interfering RNA specific for MMP-13 was used to transfect DCs. MMP-13-silenced DCs and control DCs were prepared, and apoptosis was measured using real-time polymerase chain reaction and Western blotting. MMP-13-silenced DCs and control DCs were analyzed for surface expression of CD80 and CD86 and phagocytosis capability using flow cytometry.</p><p><b>RESULTS</b>Compared to the control DCs, MMP-13-silenced DCs increased expression of anti-apoptosis-related genes, BAG1 (control group vs. MMP-13-silenced group: 4.08 ± 0.60 vs. 6.11 ± 0.87, P = 0.008), BCL-2 (control group vs. MMP-13-silenced group: 7.54 ± 0.76 vs. 9.54 ± 1.29, P = 0.036), and TP73 (control group vs. MMP-13-silenced group: 4.33 ± 0.29 vs. 5.60 ± 0.32, P = 0.001) and decreased apoptosis-related genes, CASP1 (control group vs. MMP-13-silenced group: 3.79 ± 0.67 vs. 2.54 ± 0.39, P = 0.019), LTBR (control group vs. MMP-13-silenced group: 9.23 ± 1.25 vs. 6.24 ± 1.15, P = 0.012), and CASP4 (control group vs. MMP-13-silenced group: 2.07 ± 0.56 vs. 0.35 ± 0.35, P = 0.002). Protein levels confirmed the same expression pattern. MMP-13-silenced groups decreased expression of CD86 on DCs; however, there was no statistical difference in CD80 surface expression. Furthermore, MMP-13-silenced groups exhibited weaker phagocytosis capability.</p><p><b>CONCLUSION</b>These results indicate that MMP-13 inhibition dampens DC maturation, apoptosis, and phagocytosis.</p>


Subject(s)
Animals , Female , Mice , Apoptosis , Physiology , Bone Marrow Cells , Cell Biology , Dendritic Cells , Cell Biology , Metabolism , Lipopolysaccharides , Pharmacology , Matrix Metalloproteinase 13 , Metabolism , Physiology , Mice, Inbred C57BL , RNA, Small Interfering
12.
Journal of Southern Medical University ; (12): 969-973, 2016.
Article in Chinese | WPRIM | ID: wpr-286864

ABSTRACT

Restriction by hardware caused the very low projection number at a single phase for 4-dimensional cone beam (4D-CBCT) CT imaging, and reconstruction using conventional reconstruction algorithms is thus constrained by serious streak artifacts and noises. To address this problem, we propose an approach to reconstructing 4D-CBCT images with multi-phase projections based on the assumption that the image at one phase can be viewed as the motion-compensated image at another phase. Specifically, we formulated a cost function using multi-phase projections to construct the fidelity term and the TV regularization method. For fidelity term construction, the projection data of the current phase and those at other phases were jointly used by reformulating the imaging model. The Gradient-Projection-Barzilai-Line search (GPBL) method was used to optimize the complex cost function. Physical phantom and patient data results showed that the proposed approach could effectively reduce the noise and artifacts, and the introduction of additional temporal correlation did not introduce new artifacts or motion blur.


Subject(s)
Algorithms , Artifacts , Cone-Beam Computed Tomography , Four-Dimensional Computed Tomography , Models, Theoretical , Motion , Phantoms, Imaging
13.
Acta Pharmaceutica Sinica ; (12): 979-2016.
Article in Chinese | WPRIM | ID: wpr-779266

ABSTRACT

The present project was designed to optimize the microemulsion (ME) formulation of oil in water (O/W) for dexamethasone acetate (DA), and examine its impact on DA percutaneous permeation. The saturated solubility of DA in different oils, surfactants and co-surfactants was tested. The ratio of surfactant to co-surfactant was selected by constructing pseudo three phase diagrams to investigate the maximal microemulsion area. In vitro permeation studies of DA from microemulsion and suspension were performed to optimize the formulation further. Differential scanning calorimetry (DSC) and attenuated total reflection flourier transformed infrared spectroscopy (ATR-FTIR) were performed to investigate the mechanism of microemulsion action on skin. The optimized formulation was composed of oleic acid/Labrasol/propylene glycol/water with 8/45/15/32(w/w), and the DA loading was 0.75% (w/w). The permeation enhancement of microemusion was 6.00-fold as that of suspension, and the DA from microemulsion retained in the skin was 4.79-fold as that of suspension. DSC and ATR-FTIR results suggested that microemulsion could affect the intercellular lipid lamellae and keratin of the stratum corneum. The barrier function of stratum corneum was disordered by the microemulsion so that the dermal drug delivery was enhanced. Therefore, the optimized microemulsion enhanced DA percutaneous permeation significantly through the interaction of microemulsion with skin, microemulsion is a promising approach for DA percutaneous delivery.

14.
Chinese Journal of Medical Aesthetics and Cosmetology ; (6): 143-146, 2016.
Article in Chinese | WPRIM | ID: wpr-497182

ABSTRACT

Objective To explore the long-term efficacy of botulinum toxin type A injections on facial beauty and its long-term safety.Methods A total of 33 beauty-seekers with botulinum toxin type A treatment for more than five years were reviewed as observation group,using digital muscle palpation meter (Myoton PRO) for the determination of the orbicularis oculi muscle and masseter muscle tension (F),the muscle characteristic parameters,such as muscle hardness (S) using a homemade facial questionnaire test for satisfactory rate of beauty from both beauty-seekers and physicians.At sametime,33 normal adults that never accepted botulinum toxin injection with matched age and gender were collected as control group.The same-sex indicators were dtermined and compared with using statistic analysis t test.Results The pairwised parameters of the same sex and site were comparied between the two groups;average F and S values in the observation group were lower than those of the control group,but no statistically significant difference were observed between the two groups (P>0.05);in the observation group,average appearance age was 7.3 years younger than the control group,and the facial shape improved significantly.Conclusions Long-term and repeated application of botulinum toxin A is able to remove crow's feet and decrease the masseter and so the injection is safe with high satisfaction to beauty-seekers.

15.
Journal of Southern Medical University ; (12): 375-379, 2015.
Article in Chinese | WPRIM | ID: wpr-239174

ABSTRACT

<p><b>OBJECTIVE</b>To compare two methods for threshold selection in Huber regularization for low-dose computed tomography imaging.</p><p><b>METHODS</b>Huber regularization-based iterative reconstruction (IR) approach was adopted for low-dose CT image reconstruction and the threshold of Huber regularization was selected based on global versus local edge-detecting operators.</p><p><b>RESULTS</b>The experimental results on the simulation data demonstrated that both of the two threshold selection methods in Huber regularization could yield remarkable gains in terms of noise suppression and artifact removal.</p><p><b>CONCLUSION</b>Both of the two methods for threshold selection in Huber regularization can yield high-quality images in low-dose CT image iterative reconstruction.</p>


Subject(s)
Humans , Artifacts , Image Processing, Computer-Assisted , Tomography, X-Ray Computed
16.
Journal of Southern Medical University ; (12): 1579-1585, 2015.
Article in Chinese | WPRIM | ID: wpr-232567

ABSTRACT

<p><b>OBJECTIVE</b>To develop a computed tomography myocardial perfusion (CT-MP) deconvolution algorithm by incorporating high-dimension total variation (HDTV) regularization.</p><p><b>METHODS</b>A perfusion deconvolution model was formulated for the low-dose CT-MPI data, followed by HDTV regularization to regularize the consistency of the solution by fusing the spatial correlation of the vascular structure and the temporal continuation of the blood flow signal.</p><p><b>RESULTS</b>Both qualitative and quantitative studies were conducted using XCAT and pig myocardial perfusion data to evaluate the present algorithm. The experimental results showed that this algorithm achieved hemodynamic parameter maps with better performances than the existing methods in terms of streak-artifacts suppression, noise-resolution tradeoff, and diagnosis structure preservation.</p><p><b>CONCLUSION</b>The proposed algorithm can achieve high-quality hemodynamic parameter maps in low-dose CT-MPI.</p>


Subject(s)
Animals , Algorithms , Artifacts , Models, Theoretical , Phantoms, Imaging , Swine , Tomography, X-Ray Computed
17.
Journal of Southern Medical University ; (12): 1258-1262, 2015.
Article in Chinese | WPRIM | ID: wpr-333645

ABSTRACT

Ring artifacts often appear in flat-panel detector-based CT images due to the malfunction or mis-calibration of the detector elements that result in stripe artifacts in the line integral projection (sinogram) data. The ring artifacts lower the image quality and affect image-based diagnoses. Here we propose a ring artifacts removal approach based on wavelet filtering in the sinogram domain. The line integral projection (sinogram) dataset were divided into 4 sub-sinogram dataset, and for each of them the wavelet decomposition operation was employed to produce the associated wavelet dataset, followed by filtering operation on the vertical detail band and the low-pass detail band. Wavelet reconstruction operation was then performed, and the weighted moving average filter was used to yield the filtered sinogram, which was processed using filtered back-projection (FBP) for image reconstruction. The results showed that the proposed approach could effectively remove the ring artifacts while preserving the structural information of the image.


Subject(s)
Algorithms , Artifacts , Calibration , Image Processing, Computer-Assisted , Methods , Tomography, X-Ray Computed , Wavelet Analysis
18.
Tianjin Medical Journal ; (12): 353-355,449, 2015.
Article in Chinese | WPRIM | ID: wpr-601165

ABSTRACT

Objective To study the percutaneous permeability through mouse skin of lidocaine hydrochloride-loaded destran-based niosomes(LID-HLD-BNs)in vitro and in vivo. Methods HPLC was employed to exam lidocaine hydrochlo?ride. Lidocaine hydro-chloride-loaded conventional liposomes (LID-CLs) and lidocaine hydrochloride injection (LID-IJ) were used as control. Isolated mouse skin was added into Franz diffusion cell to evaluate the permeability of LID-HLD-BNs in vitro. Confocal Laser Scanning Microscopy(CLSM)was used to observe the permeation depth of mouse skin in vivo. Re?sults The permeation rate and cumulative permeation amount were significantly higher in LID-HLD-BNs group than those of LID-CLs and LID-IJ groups (P<0.05). CLSM studies also confirmed that HLD-BNs reached deeper layers of the skin. Conclusion LID-HLD-BNs has good transdermal ability.

19.
Chinese Journal of Contemporary Pediatrics ; (12): 696-700, 2014.
Article in Chinese | WPRIM | ID: wpr-254219

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the results of Gesell Developmental Scale in follow-up of preterm infants and to determine possible high-risk factors for poor long-term neurological outcome.</p><p><b>METHODS</b>A preterm infants' questionnaire was designed, and a retrospective study was conducted on the clinical data of 181 preterm infants (corrected age 2-12 months) and their mothers. The developmental quotient (DQ) scores were determined by the Gesell Developmental Scale and statistically analyzed.</p><p><b>RESULTS</b>Compared with those with a birth weight (BW) of ≥1 500 g, the preterm infants with a BW of <1 500 g had significantly reduced DQ scores of adaptability, gross motor movement, and fine movement (P<0.05). Compared with those with a gestational age (GA) of ≥32 weeks, the preterm infants with a GA of <32 weeks had significantly reduced DQ scores of adaptability, gross motor movement, fine movement, and social contact (P<0.05). DQ scores on five Gesell subscales were significantly positively correlated with GA and BW (P<0.05). The DQ scores on Gesell subscales showed a significant negative correlation with severe complications in neonatal period (P<0.001).</p><p><b>CONCLUSIONS</b>For preterm infants, BW <1 500 g and GA <32 weeks are high-risk factors for abnormal adaptability, gross motor movement, fine movement, and social contact, and this group of infants should be followed up closely. Severe complications in neonatal period may be associated with poor long-term neurological outcome and should be effectively prevented and treated.</p>


Subject(s)
Humans , Infant , Infant, Newborn , Birth Weight , Child Development , Gestational Age , Infant, Premature , Prognosis , Retrospective Studies
20.
Chinese Journal of Clinical Infectious Diseases ; (6): 207-211, 2014.
Article in Chinese | WPRIM | ID: wpr-450240

ABSTRACT

Objective To apply special staining techniques in pathological diagnosis of fungal infections in HIV/AIDS patients.Methods Pathological data of 20 HIV/AIDS patients complicated with fungi infections in Shanghai Public Health Clinical Center during February 2010 and November 2013 were retrospectively analyzed.Tissue specimens were stained with hematoxylin and eosin (HE),Periodic acidSchiff (PAS) and methenamine silver nitrate (MSN),and the sections were observed under optical microscope.Results Among 20 HIV/AIDS patients complicated with fungi infections,2 were infected with pulmonary cryptococcosis; 3 were penicillium marneffei infections in skin,lung and abdominal mesenteric lymph nodes; 5 were histoplasma capsulatum infections in epiglottis,neck lymph nodes,oral cavity,abdominal cavity and skin; 4 were aspergillus infections in maxillary sinus,lung and vocal cords,and 3 of them were combined with tuberculous lesions; 6 were candida albicans infections in liver,pharynx,esophagus and stomach.In tissues stained with HE the infiltration of inflammatory cells,granuloma formation and coagulative necrosis were observed,and the shape of fungi needed careful observation to avoid missed diagnosis and misdiagnosis.In tissues stained with PAS,fungal spores and pseudohypha were presented in bright amaranth,and cell nucleus was in purple-blue.In tissues stained with MSN,fungal spores and pseudohypha were identified clearly in brown-black.Conclusion HE plus PAS and MSN staining will help pathological diagnosis of fungi infection.

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