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1.
Biomedical and Environmental Sciences ; (12): 431-440, 2023.
Article in English | WPRIM | ID: wpr-981071

ABSTRACT

OBJECTIVE@#To develop a few-shot learning (FSL) approach for classifying optical coherence tomography (OCT) images in patients with inherited retinal disorders (IRDs).@*METHODS@#In this study, an FSL model based on a student-teacher learning framework was designed to classify images. 2,317 images from 189 participants were included. Of these, 1,126 images revealed IRDs, 533 were normal samples, and 658 were control samples.@*RESULTS@#The FSL model achieved a total accuracy of 0.974-0.983, total sensitivity of 0.934-0.957, total specificity of 0.984-0.990, and total F1 score of 0.935-0.957, which were superior to the total accuracy of the baseline model of 0.943-0.954, total sensitivity of 0.866-0.886, total specificity of 0.962-0.971, and total F1 score of 0.859-0.885. The performance of most subclassifications also exhibited advantages. Moreover, the FSL model had a higher area under curves (AUC) of the receiver operating characteristic (ROC) curves in most subclassifications.@*CONCLUSION@#This study demonstrates the effective use of the FSL model for the classification of OCT images from patients with IRDs, normal, and control participants with a smaller volume of data. The general principle and similar network architectures can also be applied to other retinal diseases with a low prevalence.


Subject(s)
Humans , Tomography, Optical Coherence , Deep Learning , Retinal Diseases/diagnostic imaging , Retina/diagnostic imaging , ROC Curve
2.
West China Journal of Stomatology ; (6): 13-18, 2019.
Article in Chinese | WPRIM | ID: wpr-772431

ABSTRACT

OBJECTIVE@#To investigate the effect of sex determining region Y-box 9 (SOX9) on epithelial mesenchymal transition (EMT) and cloning of oral squamous cell carcinoma (OSCC).@*METHODS@#siRNA control, SOX9 siRNA were transfected into BcaCD885 cells in OSCC. Simultaneously, cells that did not undergo transfection were used as the control. Quantitative real time polymerase chain reaction (qRT-PCR) and Western blot were used to select SOX9 siRNA1 with enhanced interference effect. A cell cloning assay was used to determine the cell's clone formation ability. E-cadherin and Vimentin expressions were detected by immunofluorescence. The expressions of E-cadherin, matrix metalloprotease 2 (MMP-2), Vimentin and matrix metalloprotease 9 (MMP-9) were detected by Western blot. Cell invasion and migration were detected in the Transwell compartment.@*RESULTS@#The levels of SOX9 mRNA and protein in SOX9 siRNA cells were significantly lower than those of the control (P<0.05). An increase in the number of SOX9 siRNA1 cell clonesled to the considerable decrease of the number of cell invasion and migration. In addition, levels of MMP-2 and MMP-9 proteins in cells decreased significantly compared with the control (P<0.05). The level of Vimentin expression in SOX9 siRNA1 cells decreased, and expression level of E-cadherin was elevated. Cell EMT was inhibited compared with the control, and the difference was statistically significant (P<0.05).@*CONCLUSIONS@#Down-regulation of SOX9 inhibited EMT, clonogenic formation, cell invasion and OSCC migration.


Subject(s)
Humans , Cadherins , Carcinoma, Squamous Cell , Cell Line, Tumor , Cell Movement , Down-Regulation , Epithelial-Mesenchymal Transition , Mouth Neoplasms , Vimentin
3.
Biomedical and Environmental Sciences ; (12): 407-412, 2018.
Article in English | WPRIM | ID: wpr-690641

ABSTRACT

<p><b>OBJECTIVE</b>The aim of this study was to determine the repeatability and reproducibility of optical coherence tomography angiography (OCTA) based on optical microangiography (OMAG) measurements of macular vessels in normal eyes.</p><p><b>METHODS</b>In this prospective cohort study, 40 eyes of 40 healthy volunteers underwent repeated OCTA (Cirrus HD-OCT 5000 angiography system, Carl Zeiss Meditec, Inc.) scans on two separate visit days. On each visit day, the eyes were scanned three times. The following parameters were used to quantitatively describe the OCTA images of the superficial vascular network: vessel area density (VAD), vessel skeleton density (VSD), vessel diameter index (VDI), vessel perimeter index (VPI), vessel complexity index (VCI), flux, and foveal avascular zone (FAZ). Coefficient of variation (CV) and intraclass correlation coefficient (ICC) were calculated for evaluating intravisit and intervisit repeatability, as well as interobserver reproducibility.</p><p><b>RESULTS</b>The measurements showed high repeatability [CVs ⪕ 4.2% (intravisit) and ⪕ 4.6% (intervisit)] and interobserver reproducibility (ICCs ⪖ 0.923) for all parameters.</p><p><b>CONCLUSION</b>This study demonstrated good repeatability and reproducibility of OCTA based on OMAG for the measurement of superficial vessel parameters in normal eyes.</p>


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Young Adult , Cohort Studies , Evaluation Studies as Topic , Fluorescein Angiography , Reference Standards , Healthy Volunteers , Image Processing, Computer-Assisted , Microvessels , Diagnostic Imaging , Prospective Studies , Reproducibility of Results , Retina , Diagnostic Imaging , Retinal Vessels , Diagnostic Imaging , Tomography, Optical Coherence , Reference Standards
4.
China Journal of Orthopaedics and Traumatology ; (12): 957-960, 2017.
Article in Chinese | WPRIM | ID: wpr-259823

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the efficacy, advantages and disadvantages of internal and external elbow joint approach and olecranon osteotomy approach for the treatment of intercondylar fracture of humerus.</p><p><b>METHODS</b>From October 2012 to May 2016, 18 cases of intercondylar fracture of humerus were treated by operation including 12 males and 6 females with a mean age of 33.5 years old (ranged from 4 to 56 years old); 8 cases were operated by internal and external elbow joint approach, 10 cases were operated by olecranon osteotomy approach. According to AO classification, 3 cases were type C1, 8 cases were type C2, 7 cases were type C3. All patients were excluded from neurologic and vascular injuries.</p><p><b>RESULTS</b>All patients were followed up from 12 to 26 months with an average of 15 months. The incision healed well and no heterotopic ossification was found. According to the modified Cassebaum elbow function score, the result was excellence in 14 cases, good in 3 cases, fair in 1 case.</p><p><b>CONCLUSIONS</b>According to the fracture type, the appropriate surgical approach and fixation were selected in order to get anatomic reduction. Rigid fixation, and early functional exercise is important condition for successful operation and satisfactory functional recovery in intercondylar fracture of the humerus.</p>

5.
Chinese Medical Journal ; (24): 1292-1297, 2013.
Article in English | WPRIM | ID: wpr-342187

ABSTRACT

<p><b>BACKGROUND</b>Indirect traumatic optic neuropathy (TON) is an acute injury of the optic nerve associated with severe visual dysfunction, which may be a result of secondary mechanical injury and vascular disorder of the optic nerve due to trauma. We analyzed the natural course of axonal loss and blood flow disturbances in patients with indirect TON to find a possible therapeutic window.</p><p><b>METHODS</b>A cohort of 54 patients with indirect TON recruited between October 2008 and October 2010 at Beijing Tongren Hospital was retrospectively analyzed. The patients were divided into no light perception group (NLP) and better than NLP (btNLP) group. Specifically, the thickness of the retinal nerve fiber layer (RNFL) measured by spectral domain optical coherence tomography (SD-OCT), and hemodynamic parameters of the ophthalmic artery (OA), central retinal artery (CRA) and posterior ciliary artery (PCA) were determined.</p><p><b>RESULTS</b>Two weeks after injury, there was a statistically significant decrease in the thickness of RNFL in the btNLP group as compared with the fellow control eyes (P < 0.05). In contrast, in the NLP group, RNFL thickness slightly increased for 2 weeks following injury, then overtly reduced after 4 weeks (P < 0.05). Peak systolic velocity (PSV) of CRA was significantly decreased 4 weeks after injury (P < 0.05) in both the NLP group and btNLP group (P < 0.05). The thickness of RNFL in the NLP group was negatively correlated with PSV of CRA after 1 week of injury (P < 0.05, r = -0.962).</p><p><b>CONCLUSIONS</b>SD-OCT is a useful supplement in detecting the axonal loss in TON. The dynamic change of the thickness of RNFL appears to correlate with the hemodynamic disturbances in the natural course of TON. The first 2 weeks following an injury is critical and should be considered as the therapeutic window for TON patients.</p>


Subject(s)
Adult , Female , Humans , Male , Middle Aged , Nerve Fibers , Physiology , Optic Nerve , Physiology , Optic Nerve Injuries , Retinal Neurons , Physiology , Retrospective Studies , Tomography, Optical Coherence
6.
Chinese Journal of Applied Clinical Pediatrics ; (24): 1537-1539, 2013.
Article in Chinese | WPRIM | ID: wpr-733175

ABSTRACT

Objective To study the relationship between cyclic adenosine monophosphate/protein kinase A (cAMP/PKA) pathway and glutamine-stimulated insulin secretion.Methods In the prerequisite of the existence of glucose(0.25 mmol/L),the insulin secretion of βHC9 cells was stimulated with different concentrations of glutamine (0.0,0.5,1.0,2.0,5.0 mmol/L),then culture liquids were extracted and centrifugalized,and the insulin levels in the cell culture liquids and the cAMP levels in βHC9 cells were determined,so as to study the effects of glutamine stimulation on the insulin level in cell culture liquids and cAMP levels in βHC9 cells were assayed.Results In the prerequisite of the glucose existence,with the increasing of the concentrations of glutamine(0.0,0.5,1.0,2.0,5.0 mmol/L),the insulin levels[0.0 ng/(mL · million),19.1 ng/(mL · million),29.1 ng/(mL · million),30.1 ng/(mL · million),33.9 ng/(mL · million)] in cell culture liquids and the cAMP levels (0.0 pmol/million,40.0 pmol/million,51.5 pmol/million,52.5 pmol/million,61.3 pmoL/million) in βHC9 cells increased accordingly.Conclusion Glutamine has amplifying effect on glucose stimulated insulin secretion,such amplifying effect needs the existence of cAMP to be prerequisite.

7.
Chinese Medical Journal ; (24): 4440-4444, 2012.
Article in English | WPRIM | ID: wpr-331357

ABSTRACT

<p><b>BACKGROUND</b>Choroidal melanoma is the most common intraocular malignant tumor in adults. It threatens not only the visual function but also the patient's life. Therefore, it is important to find a non-traumatic, quantitative and repetitive diagnostic method. This study investigated the value of quantitative analysis of contrast-enhanced ultrasound (CEUS) in the diagnosis of choroidal melanoma.</p><p><b>METHODS</b>CEUS were performed in 51 cases of choroidal melanoma, which were diagnosed either pathologically or clinically and in 14 cases of choroidal hemangioma. The characteristics of the time-intensity curve of the contrast agent were analyzed. For the quantitative analysis, the following parameters of the contrast agent in the lesion were included: rising time (RT), time to peak (TTP), maximum intensity (MI) and the mean transit time (MTT).</p><p><b>RESULTS</b>Choroidal melanoma had the following characteristics on CEUS: Choroidal lesions were completely filled with contrast agent. The typical filling pattern was centripetal, with the peripheral of the choroidal lesion filled with the contrast agent first and then the center of the lesion. In some cases, areas with contrast agent filling defect were observed in the lesions. The contrast agent filled the lesion slower than the normal eye and orbital tissue but faded faster in the lesion. Quantitative analysis showed that in choroidal melanoma, MI of contrast agent (191.31% ± 146.90%) was significantly more than that of the normal tissue (100.00% ± 0.00%) (P < 0.05) and MTT ((63.56 ± 26.04) seconds) was significantly less than that of the normal tissue ((149.87 ± 182.68) seconds) (P < 0.05). TTP (22.80 ± 9.85) was less than that of the normal tissue ((29.57 ± 24.76) seconds) and RT ((18.52 ± 7.09) seconds) was less than that of the normal tissue ((26.45 ± 21.83) seconds). Both the differences of TTP and RT were not statistically significant though. Logistic regression showed that to predict choroidal melanoma and choroidal hemangioma with MI and MTT, the sensitivity was 90.5% and the specific degrees was 85.7%.</p><p><b>CONCLUSIONS</b>CEUS is a new method to diagnose tumors in the eye. Choroidal melanoma may be diagnosed objectively and accurately by combining the graphic characteristics on CEUS and the time-intensity curve quantitative analysis.</p>


Subject(s)
Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Choroid Neoplasms , Diagnosis , Diagnostic Imaging , Contrast Media , Melanoma , Diagnosis , Diagnostic Imaging , Ultrasonography
8.
Chinese Journal of Experimental Ophthalmology ; (12): 692-698, 2012.
Article in Chinese | WPRIM | ID: wpr-635870

ABSTRACT

Background Choroidal melanoma (CM)is the most common primary intraocular tumor,and brachytherapy is one of the most common therapeutic modality in the treatment of the tumor.However,this irradiation approach has not been evaluated in China. Objective The present study was to analyze the effectiveness and safety of domestic 125I plaque irradiation in the treatment of CM. Methods Forty New Zealand albino rabbits were randomized into 5 groups with 8 rabbits 8 eyes (right eyes) in each group.CM models were established in 16 of 40 New Zealand albino rabbits by implanting the rat B16F10 melanoma cell fragments into the suprachoroidal space of right eyes.After 3 weeks,domestic 125I plaque was fixed at the location of CM in the irradiation group 1,and 8 rabbits with CM served as model control group.The clinical effectiveness of 125I plaque for CM was evaluated based on the fundus examination with indirect ophthalmoscopy,B scan ultrasonography,fundus photographs and color Dopplerimaging.Regarding the safety study,domestic 125I plaque was fixed on the normal right cycs of normal rabbits,while the plaques without 125I seeds were used as the sham group.No intervene was performed in the rabbits of blank group.The number of CD4+,CD8+ T cells in peripheral blood was detected by flow cytometry before plaques implanted and on 3,7,15 and 30 days after the plaque was removed.The animals were sacrificed and the eyes were obtained for histology examination.The use of the experimental animals complied with Statement of ARVO. Results After implantation of B16F10 melanoma cell fragments,CM grew steadily and rapidly with the similar size between irradiation group 1 and model control group ( P =0.550).One week after administration of the treatment,tumor size was(0.31±0.07 )cm in irradiation group 1 and (0.85±0.18 )em in the model control group,with the significant difference between them( P=0.001 ).Two week after application of 125I plaque,the size of tumor was smaller than that before irradiation (P=0.007 ).Histologically,the tumors were mostly limited beneath the pigment epithelial layer with less neovascularization,fibrosis in the tumor was found in some area in the irradiation group when compared with model control group.No significant differences were found in the proportions of CD4+,CD8+ T cells and CD4+/CD8+ at different time points in the irradiation groups of normal eyes and sham group (Fgroup =0.770,8.110,2.230; P=0.380,0.060,0.140; Ftime =0.770,3.220,4.230; P =0.550,0.170,0.004 ).Chronic inflammatory cells infiltration cornea,subconjunctival epithelial and selera surface,but sclera had no necrosis and organization.Conclusions These results suggest that domestic 125I plaque irradiation is effective for the treatment of CM,and has limited side effects on normal rabbits.

9.
West China Journal of Stomatology ; (6): 118-124, 2011.
Article in Chinese | WPRIM | ID: wpr-350222

ABSTRACT

<p><b>OBJECTIVE</b>To study the distribution of stress of simulating teeth with wedge shaped defects in the cervical region.</p><p><b>METHODS</b>The models of anisotropic enamel of the mandibular first premolar and the opposite maxillary first premolar crown were created. A defect was introduced into the model of mandibular premolar in the buccal cervical region along the enamelo-dentinal junction (DEJ). The stress distribution in the cervical region of the mandibular premolar was investigated considering lateral condition simulating working micromotions. In this case, the stroke was applied to the maxillary first mandibular in a stepping procedure using nonlinear contact analysis.</p><p><b>RESULTS</b>The stresses were concentrated in the defect of the enamel and dentin at the DEJ in the condition of lateral loading. As the defect length increased in size, the peak maximum principal stress (MPS) value and the magnitude of the stress field along the DEJ both increased.</p><p><b>CONCLUSION</b>Undermined cervical DEJ had a significant effect on the stress distribution in the buccal cervical region.</p>


Subject(s)
Humans , Bicuspid , Dental Enamel , Dental Stress Analysis , Dentin , Finite Element Analysis , Mandible , Maxilla
10.
Chinese Medical Journal ; (24): 2152-2156, 2008.
Article in English | WPRIM | ID: wpr-350783

ABSTRACT

<p><b>BACKGROUND</b>Ciliary body tumors are usually difficult to diagnose and treat in early stages. However, treatment of such tumors has trended toward ocular conservation instead of enucleation. Local excision of ciliary body tumors has become effective with the development of the modern vitrectomy, but long-term outcomes are still not clear. Therefore, we reported the outcome of locally excised ciliary body tumors after long-term follow-up.</p><p><b>METHODS</b>Twenty-two patients (22 eyes), who had been diagnosed with ciliary body tumors in Beijing Tongren Hospital from January 1996 to June 2001, were enrolled in this prospective cohort study. Localized lamellar sclera-ciliary excisions were performed. In some cases, vitrectomies, scleral graft transplantations, and further excisions of the anterior choroid were performed. Diagnoses were confirmed by histopathologic examination. Patients were followed from five to eleven years after surgery. Their visual acuity, intraocular pressure and local recurrence were recorded with descriptive percentages.</p><p><b>RESULTS</b>After surgery, all patients maintained normal eyeball appearances. Six patients maintained circular pupils. The final best corrected visual acuities (BCVA) varied from 0.02 - 1.00, including 18 patients (81.82%) who had BCVA equal to or better than that before surgery. Fifteen patients (68.18%) had BCVA better than 0.3. Only two patients had intraocular pressure (IOP) of less than 10 mmHg and the other patients maintained normal IOP. Nine cases (40.91%) were given confirmed diagnosis of malignant melanoma, four (18.18%) of melanocytoma, six (27.27%) of nonpigmented ciliary epithelial adenoma, two (9.09%) of neurofibroma, and one (4.55%) of neurinoma. Twenty patients (90.91%) had no recurrence during the follow-up period. In one case melanocytoma recurred seven years after surgery and enucleation was performed. One patient, whose operation removed a malignant melanoma with a diameter of 16 mm, died of hepatic metastasis five years after the operation.</p><p><b>CONCLUSION</b>For some ciliary body tumors, especially in the early stages, local excision is an effective and safe method to save the vision and the eyeball.</p>


Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Ciliary Body , Cohort Studies , Intraocular Pressure , Melanoma , General Surgery , Prospective Studies , Uveal Neoplasms , Diagnosis , Pathology , General Surgery , Visual Acuity
11.
West China Journal of Stomatology ; (6): 383-385, 2007.
Article in Chinese | WPRIM | ID: wpr-348042

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the relationship between wedge-shaped defects and occlusal interference.</p><p><b>METHODS</b>Following examination from 46 patients, a total of 157 teeth were identified to have the criteria set for wedge-shaped defects and regarded as the experiment group. Also, 157 adjacent teeth exhibiting no such noncarious cervical lesions were randomly selected from the same group of patients and regarded as the control group. The distribution of occlusal force and time were examined with T-Scan II system in 46 patients with wedge-shaped defects in intercuspal occlusion position, protrusive movement and lateral movement. Occlusal interference and premature contact were evaluated and compared between the two groups.</p><p><b>RESULTS</b>The proportion of the teeth with premature contact in experiment group was 6.37%, while the control group was 2.55%, there was no significant difference between the two groups (P > 0.05). The total proportion with occlusal interferences in experiment group was 23.57%, which was significantly higher than that of the control group (10.19%, P < 0.05), in experiment group the proportion with working side interferences was 15.92%, and in control group, the proportion was 3.82%, there was significant difference between the two groups (P < 0.01). At the same time, the teeth with occlusal interferences had more serious degree of the wedge-shape defects than those with no occlusal interference.</p><p><b>CONCLUSION</b>The increased occlusal force has relation to the formation as well as severity of wedge-shaped defects.</p>


Subject(s)
Humans , Male , Bicuspid , Bite Force , Dental Occlusion , Tooth Abrasion
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