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1.
Journal of Preventive Medicine ; (12): 803-808, 2022.
Article in Chinese | WPRIM | ID: wpr-936799

ABSTRACT

Objective@#To identify the most appropriate meteorological variable for forecasting the health risk of high temperatures.@*Methods@#The surveillance on causes of death, meteorological data and surveillance on air quality among registered residents in Ningbo City, Zhejiang Province during the period between May and October from 2013 to 2019 were collected. The association models of daily minimum temperature, average daily temperature, daily maximum temperature, daily minimum heat index, average daily heat index, daily maximum heat index, average daily apparent temperature and torridity index with deaths and years of life lost (YLL) were created using time series analysis and distributed lag non-linear models, and the model fitting effect was evaluated using the minimum Akaike information criterion (AIC) procedure. The most appropriate meteorological variable for forecasting gender-, age- and mortality-specific health risks of high temperatures was identified.@*Results@#A total of 120 628 deaths were reported during the study period, with daily deaths of 94 cases, and daily YLL rate of 19.74 person-years/105. Except for daily minimum heat index and torridity index, the exposure-response relationships between other six meteorological variables and deaths and overall YLL rate all appeared a “J” shape. The lowest AIC values and the optimal model fitting effects were measured for the association models between average daily temperature and whole populations, females, subjects at ages of 65 years and older, and deaths and YLL rates due to circulatory diseases and respiratory diseases.@*Conclusion@#High model fitting effects are observed between average daily temperature and deaths and YLL rates, which are more suitable for forecasting the health risk of high temperature.

2.
Article in Chinese | WPRIM | ID: wpr-936155

ABSTRACT

OBJECTIVE@#To explore the construction process of the digital reference crown models, and to initially establish the digital reference crown models of the primary teeth to lay the foundation for the establishment of the standardized crown models and the future related applications of computer-aided design/computer-aided manufacture (CAD/CAM) technology to pediatric dentistry.@*METHODS@#This study randomly selected children who were caries free, aged from 4 to 5 years in several kindergartens of Haidian District of Beijing.Plaster dental models were made for the children after taking complete impressions.The digital dental models were reconstructed by using the three-dimensional (3D) dental model scanner.And then, Geomagic Studio, a 3D reverse engineering software, was employed to extract the single dental crown data, the mesiodistal and buccolingual diameters and the height of the crowns were measured.The object was reduced or enlarged by a numerical factor, and then the size of each dental crown was standardized.A total of 3-5 points features on the crown were created, and all the objects were aligned through the functions of feature-based alignment.Finally, through average-based object creation and smoothing, the digital models of reference crowns of the primary teeth were established.@*RESULTS@#A total of 40 plaster dental models from 16 boys and 26 girls were selected out for our further study.The digital dental models were reconstructed, and the mesiodistal and buccolingual diameters and the height of the crowns were measured by using reverse engineering technology.Comparing the results of using mesiodistal diameter, buccolingual diameter and height as the standards, we chose the mesiodistal diameters of crowns to do the standardization, and successfully established the digital reference models of 20 primary teeth crowns with detailed surface characteristics.@*CONCLUSION@#In this study, the digital reference crown models of the primary teeth were established by reverse engineering technology, providing reference value for the standardized crown models and application for clinical practice, scientific research and teaching.Furthermore, this study also contributes to the extensive application of CAD/CAM technology in pediatric dentistry and the development of CAD/CAM dental systems with independent intellectual property rights.


Subject(s)
Child , Computer-Aided Design , Crowns , Dental Prosthesis Design , Female , Humans , Male , Software , Tooth Crown , Tooth, Deciduous
3.
Article in Chinese | WPRIM | ID: wpr-923776

ABSTRACT

Objective To examine the effects of Toxoplasma gondii infection on the proportion, quantity, differentiation and function of mouse and human uterine natural killer cells (uNK cells), so as to explore the role of uNK cells in abortion of early pregnancy caused by T. gondii infection. Methods Pregnant mice were injected intraperitoneally with T. gondii tachyzoites on day 6.5 of pregnancy, and the abortion mouse model caused by T. gondii infections was constructed. Mouse uterine lymphocytes were isolated on day 9.5 of pregnancy. Human uterine lymphocytes were isolated from fresh human decidual specimens after abortion in normal early pregnancy and co-cultured with tachyzoites of the T. gondii RH strain for 48 h at T. gondii/uterine lymphocytes ratios of 0.5:1, 1:1 and 2:1. The phenotypes of mouse uNK cells (CD122, NK1.1, DX5) and human uNK cells (CD3, CD56, CD11b, CD27) and the expression of intracellular cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) were detected by flow cytometry. Mouse and human uNK cells were sorted by magnetic beads, and the cytotoxicity of uNK cells was tested using the lactate dehydrogenase (LDH) release assay at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1 with mouse or human uNK cells as effector cells and mouse YAC-1 cells or human K562 cells as target cells. Results On day 9.5 of pregnancy, the mouse abortion rate was significantly higher in the infected group than that in the control group (83.02% vs. 3.51%; χ2 = 71.359, P < 0.001). Significantly lower absolute number of uNK cells [(4 547 ± 1 610) cells/mouse vs. (8 978 ± 3 339) cells/mouse; U = 2.000, P < 0.05], lower NK1.1 expression on uNK cell surface [(74.53 ± 8.37)% vs. (93.00 ± 1.11)%; U = 0.000, P < 0.05], higher proportion of NK1.1-DX5-cells [(20.10 ± 8.03)% vs. (5.04 ± 0.68)%; U = 0.000, P < 0.05], lower proportion of NK1.1+ DX5+ cells [(21.70 ± 12.48)% vs. (45.75 ± 2.26)%; U = 0.000, P < 0.05] and higher IFN-γ expression [(16.74 ± 1.36)% vs. (8.13 ± 1.90)%; U = 0.000, P < 0.05] were detected in the infected group than in the control group, while no significant difference was seen in TNF-α expression between the two groups [(67.98 ± 9.20)% vs. (52.93 ± 10.42)%; U = 2.000, P > 0.05]. The mouse uNK cells showed a strong cytotoxicity in the infected group, and the cytotoxicity gradually increased with the effector/target cell ratio. The cytotoxicity of uNK cells against YAC-1 cells was 2.30%, 4.32%, 8.12% and 12.65% in the infected group and 1.21%, 1.63%, 2.51% and 3.22% in the control group at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1, respectively. Following co-culture of human uterine lymphocytes and tachyzoites of the T. gondii RH strain for 48 h, the proportion [TOX 2:1 group vs. control group: (6.61 ± 1.75)% vs. (17.48 ± 4.81)%; F = 7.307, P < 0.01], and absolute number of human uNK cells in uterine lymphocytes of human uNK cells in uterine lymphocytes [TOX 2:1 group vs. control group: (12 104 ± 5 726) cells/well vs. (65 285 ± 21 810) cells/well; H = 11.540, P < 0.01] were significantly lower in the infected group than in the control group. A lower proportion of CD56brightCD16- NK cells [TOX 2:1 group vs. control group: (25.25 ± 5.90)% vs. (36.03 ± 4.51)%; F = 3.213, P > 0.05] and higher proportion of CD56dimCD16+ NK cells [TOX 2:1 group vs. control group: (11.15 ± 2.15)% vs. (7.09 ± 2.24)%; F = 2.992, P > 0.05] were detected in uNK cells in the infected group than in the control group, and the ratio of CD56brightCD16- cells/CD56dimCD16+ cells was significantly lower in the infected group than in the control group [TOX2:1 group vs. control group: (2.37 ± 0.92) vs. (5.58 ± 2.39); H = 8.228, P < 0.05]. In addition, the proportion of CD11b+CD27- cells in human uNK cells was significantly higher in the infected group than in the control group [TOX 2:1 group vs. control group: (30.28 ± 6.91)% vs. (17.48 ± 4.67)%; H = 6.556, P < 0.05], while no significant differences were found between the two groups in terms of IFN-γ [TOX 2:1 group vs. control group: (14.13 ± 1.28)% vs. (15.19 ± 1.64)%; F = 1.639, P > 0.05] or TNF-α expression [TOX 2:1 group vs. control group: (54.76 ± 10.02)% vs. (50.33 ± 3.67)%; F = 0.415, P > 0.05]. Human uNK cells presented a strong cytotoxicity in the infected group, and the cytotoxicity gradually increased with the effector/target cell ratio. The cytotoxicity of human uNK cells against K562 cells was 11.90%, 28.11%, 49.91% and 73.35% in the infected group and 12.21%, 21.63%, 33.51% and 48.22% in the control group at effector/target cell ratios of 1:1, 5:1, 10:1 and 20:1, respectively. Conclusions T. gondii infection presents diverse effects on the differentiation and secretion ability of mouse and human uNK cells. However, T. gondii infection causes a reduction in the absolute number and enhances the cytotoxicity of both mouse and human uNK cells.

4.
China Pharmacy ; (12): 885-890, 2022.
Article in Chinese | WPRIM | ID: wpr-923198

ABSTRACT

OBJECTIVE To provide reference and ideas for optimizing the continuing education system of pharmacists in China. METHODS By introducing the continuing professional development (CPD)model of pharmacists in Japan ,the current situation and existing problems for continuing education of pharmacists in China were analyzed to puts forward some suggestions. RESULTS & CONCLUSIONS The continuing education system of CPD model for pharmacists in Japan included five continuous cycle processes :self-assessment,making plan ,implementing plan ,learning record and result evaluation. It emphasized the autonomy and sustainability of pharmacists ’learning and promoted the sustainable development of pharmacists ’career. The education and training of pharmacists in Japan were subject to the certification system ,and a diversified implementation organization composed of industry associations ,colleges and universities and commercial education institutions had been formed. After continuous reform ,Japan had established a relatively mature and perfect sustainable career development model for pharmacists. Our country can refer to the CPD model of Japanese pharmacists ,promote the legislation of pharmacists ,explore the unified management model (the unity of hospital pharmacists and licensed pharmacists ),explore the construction of pharmacists ’ continuing education certification mechanism ,carry out refined continuing education for pharmacists in different practice fields , improve the enthusiasm of industry associations ,and add practical content to pharmacists ’continuing education projects.

5.
Journal of Clinical Hepatology ; (12): 1999-2004, 2022.
Article in Chinese | WPRIM | ID: wpr-942650

ABSTRACT

In March 2022, EASL released a new version of the clinical practice guidelines on haemochromatosis. Haemochromatosis is characterized by elevated transferrin saturation (TSAT) and progressive iron overload mainly involving the liver, and early diagnosis and venesection can prevent liver cirrhosis, hepatocellular carcinoma, diabetes, arthritis, and other complications. For patients with p.Cys282Tyr homozygous mutation of the hemochromatosis gene HFE , haemochromatosis can be diagnosed if serum iron parameters show TSAT > 45% and ferritin > 200 μg/L in female patients, or TSAT > 50% and ferritin > 300 μg/L in male patients and postmenopausal female patients. If a patient has elevated TSAT and ferritin and belongs to other HFE genotypes, magnetic resonance or liver biopsy is needed to confirm iron overload in the liver. Liver fibrosis stage and damage to other organs should be carefully assessed at the time of diagnosis, which will help to determine management strategies. Hepatocellular carcinoma should be screened for patients with progressive liver fibrosis. The goal of venesection is to achieve ferritin < 50 μg/L during the induction stage and ferritin < 100 μg/L during the maintenance stage.

6.
Article in Chinese | WPRIM | ID: wpr-940841

ABSTRACT

Objetive: To investigate the mechanism of antidepressant effect of verbascoside based on high-throughput sequencing technology (RNA-Seq),and to explore the possible targets and signaling pathways. MethodsForty C57BL/6 mice were randomly divided into control group,model group,fluoxetine group and verbascoside group,10 mice in each group. Except for the control group,all the other three groups were constructed with chronic unpredictable mild stimulation (CUMS) combined with solitary feeding for four weeks. Control group,fluoxetine group and verbascoside group were administered by gavage once daily for three weeks during the second week of modeling. The mice were assessed by sugar-water preference test,forced swimming test,open field test,elevated cross maze test,and water maze test. Enzyme linked immunosorbent assay(ELISA) was performed to detect the levels of major neurotransmitters and inflammatory factors in mice serum,and mRNA high-throughput sequencing was performed in the nucleus accumben and colon to screen differentially expressed genes and perform pathway enrichment analysis. Real-time polymerase chain reaction(Real-time PCR) was used to detect the mRNA expression of Gad,Slc32a1(VGAT) and brain-derived neurotrophic factor (BDNF) in nucleus accumbens. ResultCompared with the control group,the anxiety and depression-like behaviors in the model group increased,while the learning and memory ability decreased significantly. The content of neurotransmitter in serum decreased significantly. The content of pro-inflammatory factors increased significantly. The mRNA expression of Gad and Slc32a1(VGAT) in nucleus accumbens decreased significantly,while that of BDNF increased significantly. Compared with the model group,the anxiety and depression-like behavior of mice in verbascoside group was significantly relieved. The neurotransmitter content increased significantly,and the pro-inflammatory factors decreased significantly. The mRNA expression of Gad and Slc32a1(VGAT) in nucleus accumbens increased significantly,while that of BDNF decreased significantly.A total of 48 differentially expressed genes in nucleus accumbens and 43 differentially expressed genes in colon were screened by high-throughput sequencing. Differential genes in nucleus accumbens mainly focus on neuroactive ligand-receptor interaction, γ-aminobutyric acid(GABA)ergic synapse,synaptic vesicle cycle and other pathways. Colonic differential genes are mainly concentrated in GABAergic synapses,synaptic vesicle circulation,cyclic adenosine monophosphate(cAMP) signal pathway and other signal pathways. Compared with the control group,the mRNA expression of Gad and Slc32a1(VGAT) in nucleus accumbens of model group decreased significantly,while the mRNA expression of BDNF increased significantly. ConclusionVerbascoside has significant antidepressant effects. Its antidepressant effect may be related to the increase of monoamine neurotransmitters,the decrease of pro-inflammatory factors and the restoration of neurotransmitter homeostasis by increasing GABA,and it mainly acts through the signaling pathways such as neuroactive ligand-receptor interaction,GABAergic synapses,synaptic vesicle cycle and cAMP signaling pathway.

7.
Article in Chinese | WPRIM | ID: wpr-940690

ABSTRACT

ObjectiveTo establish a traditional Chinese medicine (TCM) syndrome model with yin deficiency and internal heat, discuss the rationality of model evaluation, and analyze differentially expressed genes in multiple dimensions to explore the molecular mechanism-signaling pathways as well as key targets of Baihe Dihuangtang (BHDH) in treating depression with Yin deficiency and internal heat. MethodForty male SD rats were randomly divided into a blank control group,a model group,a fluoxetine group (positive drug),a BHDH group, and a Zhibai Dihuangtang group (positive drug for Yin deficiency and internal heat). The depression model with Yin deficiency and internal heat was induced by chronic unpredictable mild stress (CUMS)combined with Chinese herbal drugs with warm and heat nature. The model established was comprehensively evaluated by the detection of the basic condition, behavioral performance, and biochemical indicators of rats in each group. The differentially expressed genes were screened out by mRNA sequencing and underwent Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses. The protein-protein interaction (PPI) network was plotted and key genes were analyzed to explore the underlying mechanism of BHDH in treating depression with Yin deficiency and internal heat. ResultThe comparison of basic conditions, behavioral assays, energy metabolism, endocrine hormones, cytokines, and neurotransmitters showed that the model was properly induced. BHDH could significantly improve depression with Yin deficiency and internal heat by regulating the pathways related to the nervous system, endocrine system, and inflammatory and immune system. The key genes of the PPI network were Fos, Epha8, Npy2r, Htr2c, and Nr4a1. ConclusionUnder the guidance of TCM theories of treatment based on syndrome differentiation and etiology and pathogenesis,this study established a depression model with yin deficiency and internal heat in animals and evaluation system in accordance with the symptoms and signs of emotional diseases, and further confirmed the scientificity of the modeling method and the underlying mechanism of BHDH in interfering with depression with Yin deficiency and internal heat based on the results of mRNA sequencing.

8.
Article in Chinese | WPRIM | ID: wpr-940370

ABSTRACT

In the clinical practice of rheumatic immune diseases in traditional Chinese medicine (TCM),it`s still unclear about the dominant diseases and breakthrough points. It`s urgent missions to formulate TCM diagnosis and treatment guidelines widely recognized and integrated by traditional Chinese medicine and Western medicine. In order to clarify the dominant diseases and breakthrough points in rheumatism,China association of Chinese medicine initiated a research group covering experts in the field of rheumatism of traditional Chinese medicine and Western medicine. Based on questionnaire survey and on-site discussion,experts had reached the following consensus. Evidence-based medicine research using modern medical methods and scientific methods should be carried out to provide objective clinical evidences. "Four mutuality" were put forward as the basis for the work of integrated traditional Chinese and Western medicine,that is the mutual communication using the exchangeable context,the mutual explanation using common theories,the mutual certification using common standards,and the mutual integration using common means. Key works should focus on solving refractory rheumatism in the future. In terms of dominant diseases and breakthrough points,this paper introduces 21 breakthrough points in 6 dominant diseases,including rheumatoid arthritis,ankylosing spondylitis,Sjogren's syndrome,hyperuricemia and gout,systemic lupus erythematosus and fibromyalgia syndrome. Advice on this discussion can provide valuable references for developing the treatment scheme of rheumatism with TCM and integrated Chinese and Western medicine and clinical practice and scientific research.

9.
International Eye Science ; (12): 1523-1527, 2022.
Article in Chinese | WPRIM | ID: wpr-940015

ABSTRACT

AIM:To evaluate the application effect of iris hooks combined with suture fixation of capsular tension ring(CTR)in the treatment of phacoemulsification with secondary glaucoma associated with lens subluxation.METHODS: Retrospective case series. A total of 18 eyes of patients with serious secondary glaucoma associated with lens subluxation were enrolled in Aier Eye Hospital(Changchun)from October 2017 to May 2020 as the observation group. All the patients had iris hooks inserted to support the capsule during the phacoemulsification combined with intraocular lens(IOL)implantation. Iris hooks were inserted through the incisions and placed in the capsulorhexis to support the capsule, then CTR was implanted and sutured onto the sclera of the dislocation side. A total of 11 eyes of patients had intracapsular cataract extraction combined with IOL suspension were enrolled in Aier Eye Hospital(Changchun)from October 2015 to October 2017 as the control group. The postoperative complications were recorded. The postoperative examinations included visual acuity, intraocular pressure(IOP)and positions of the capsule and IOL.RESULTS: The postoperative follow-up at least 12(12-40)mo, both the IOP of observation group and control group returned to normal, with statistically significant difference compared with pre-operation(t=9.994, 8.790, all P&#x003C;0.001). At 12mo after operation, the best corrected visual acuity of the two groups were significantly improved compared with surgery before(Z=-3.900, P&#x003C;0.001; Z=-3.002, P=0.003). The IOL in the observation group of the 18 eyes were in the expected position without complications such as an obvious tilt or displacement. In the control group with 11 eyes, the position of IOL in 8 eyes were centered, 3 eyes were slightly biased, and 2 eyes with cystoids macular edema.CONCLUSION: The application of suture fixation capsular tension ring and iris hooks for secondary glaucoma associated with lens subluxation in patients can be used as an effective auxiliary method, it could effectively control the IOP and maintain long-term stability of the capsule.

10.
Article in Chinese | WPRIM | ID: wpr-936134

ABSTRACT

OBJECTIVE@#To automatically construct lips symmetry reference plane (SRP) based on posed smile, and to evaluate its advantages over conventional digital aesthetic design.@*METHODS@#Eighteen subjects' three-dimensional facial and dentition data were gathered in this study. The lips SRP of experimental groups were used with the standard weighted Procrustes analysis (WPA) algorithm and iterative closest point (ICP), respectively. A reference plane defined by experts based on regional ICP algorithm, served as the truth plane. The angle error values between the lips SRP of WPA algorithm in the experimental groups and the truth plane were evaluated in this study, and the lips SRP of ICP algorithm of the experimental groups was calculated in the same way. The lips SRP based on posed smile as a reference for aesthetic design and evaluate preliminary clinical application.@*RESULTS@#The average angle error between the lips SRP of WPA algorithm and the truth plane was 1.78°±1.24°, which was smaller than that between the lips SRP of ICP and the truth plane 7.41°±4.31°. There were significant differences in the angle errors among the groups (P < 0.05). In the aesthetic design of anterior teeth, automatically constructing the lips SRP of WPA algorithm based on posed smile and the original symmetry plane by re-ference compared with the prosthetic design, the subjects' scores on the lips SRP of WPA algorithm based on posed smile (8.48±0.57) were higher than those on the original symmetry plane (5.20±1.31).@*CONCLUSION@#Automatically constructing the lips SRP of WPA algorithm based on posed smile was more accurate than ICP algorithm, which was consistent with the truth plane. Moreover, it can provide an important reference for oral aesthetic diagnosis and aesthetic analysis of the restoration effect. In the aesthetic design of anterior teeth, automatically constructing the lips SRP of WPA algorithm based on posed smile can improve the patients' satisfaction in esthetic rehabilitation.


Subject(s)
Esthetics, Dental , Humans , Lip , Smiling , Tooth , Workflow
11.
Article in Chinese | WPRIM | ID: wpr-936124

ABSTRACT

OBJECTIVE@#To establish a deep learning algorithm that can accurately determine three-dimensional facial anatomical landmarks, multi-view stacked hourglass convolutional neural networks (MSH-CNN) and to construct three-dimensional facial midsagittal plane automatically based on MSH-CNN and weighted Procrustes analysis algorithm.@*METHODS@#One hundred subjects with no obvious facial deformity were collected in our oral clinic. Three-dimensional facial data were scanned by three-dimensional facial scanner. Experts annotated twenty-one facial landmarks and midsagittal plane of each data. Eighty three-dimensional facial data were used as training set, to train the MSH-CNN in this study. The overview of MSH-CNN network architecture contained multi-view rendering and training the MSH-CNN network. The three-dimensional facial data were rendered from ninety-six views that were fed to MSH-CNN and the output was one heatmap per landmark. The result of the twenty-one landmarks was accurately placed on the three-dimensional facial data after a three-dimensional view ray voting process. The remaining twenty three-dimensional facial data were used as test set. The trained MSH-CNN automatically determined twenty-one three-dimensional facial anatomical landmarks of each case of data, and calculated the distance between each MSH-CNN landmark and the expert landmark, which was defined as position error. The midsagittal plane of the twenty subjects' could be automatically constructed, using the MSH-CNN and Procrustes analysis algorithm. To evaluate the effect of midsagittal plane by automatic method, the angle between the midsagittal plane constructed by the automatic method and the expert annotated plane was calculated, which was defined as angle error.@*RESULTS@#For twenty subjects with no obvious facial deformity, the average angle error of the midsagittal plane constructed by MSH-CNN and weighted Procrustes analysis algorithm was 0.73°±0.50°, in which the average position error of the twenty-one facial landmarks automatically determined by MSH-CNN was (1.13±0.24) mm, the maximum position error of the orbital area was (1.31±0.54) mm, and the minimum position error of the nasal area was (0.79±0.36) mm.@*CONCLUSION@#This research combines deep learning algorithms and Procrustes analysis algorithms to realize the fully automated construction of the three-dimensional midsagittal plane, which initially achieves the construction effect of clinical experts. The obtained results constituted the basis for the independent intellectual property software development.


Subject(s)
Algorithms , Deep Learning , Face , Humans , Neural Networks, Computer , Software
12.
Article in Chinese | WPRIM | ID: wpr-936120

ABSTRACT

OBJECTIVE@#To compare the retentions of different designs of cobalt-chromium (Co-Cr), pure titanium (CP Ti), and titanium alloy (Ti-6Al-4V) removable partial denture (RPD) circumferential clasps manufactured by selective laser melting (SLM) and to analyze the stress distribution of these clasps during the removal from abutment teeth.@*METHODS@#Clasps with clasp arm size A (1.9 mm width/1.1 mm thickness at the body and 0.8-taper) or B (1.2 times A) and 0.25 mm or 0.50 mm undercut engagement were modeled on a prepared first premolar die, named as designs A1, A2, A3, and A4, respectively. The density and elastic modulus of SLM-built Co-Cr, CP Ti, and Ti-6Al-4V were measured and given to different groups of clasps. The density, elastic modulus, and Poisson ' s ratio of enamel were given to the die. The control group was the cast Co-Cr clasp with design A1, to which the density and elastic modulus of cast Co-Cr alloy were given. The Poisson's ratio of all metals was 0.33. The initial 5 N dislodging force was applied, and the maximum displacement of the clasp along the insertion path was computed. The load was reapplied with an increment of 5 N than in the last simulation until the clasp was completely dislodged. The retentive force range of different groups of clasps was obtained. The retentive forces of the SLM-built Co-Cr, CP Ti, and Ti-6Al-4V clasps with equivalent computed retentive force range to the control group were validated through the insertion/removal experiment. The von Mises stress distributions of these three groups of SLM-built clasps under 15 N loads were analyzed.@*RESULTS@#SLM-built Co-Cr, CP Ti, and Ti-6Al-4V clasps with designs B1 or B2, and Co-Cr clasps with design A2 had higher retentive forces than those of the control group. SLM-built CP Ti and Ti-6Al-4V clasps with design A1 had lower retentive forces than those of the control group. SLM-built Co-Cr clasp with design A1 and SLM-built CP Ti and Ti-6Al-4V clasps with design A2 had equivalent retentive forces to those of the control group. The insertion/removal experiment showed that the measured retentive forces of these three groups of SLM-built clasps were (21.57±5.41) N, (19.75±4.47) N, and (19.32±2.04) N, respectively. No statistically significant measured retentive force difference was found among these three groups of SLM-built clasps (P>0.05). The maximum von Mises stress of these three groups of SLM-built clasps exceeded their responding yield strength except for the Ti-6Al-4V one.@*CONCLUSION@#SLM-built Co-Cr circumferential clasps had higher retention than CP Ti and Ti-6Al-4V ones with the same clasp arm size and undercut engagement. The retention of SLM-built circumferential clasps could be adjusted by changing the undercut engagement and clasp arm size. If SLM-built circumferential clasps are used in clinical practice, the Ti-6Al-4V clasp with clasp arm size A and 0.50 mm undercut engagement is recommended considering the long-term use of RPD in the patient's mouth.


Subject(s)
Chromium Alloys , Dental Clasps , Denture Retention , Denture, Partial, Removable , Finite Element Analysis , Humans , Lasers , Titanium
13.
Chinese Journal of Stomatology ; (12): 540-546, 2022.
Article in Chinese | WPRIM | ID: wpr-935899

ABSTRACT

With the advent of the era of big data, artificial intelligence based on machine learning, especially artificial neural network has rapidly developed and applicated in the field of stomatology, owning huge potential in segmentation and labelling of three-dimensional intraoral anatomical features. Automatic segmentation, labelling and diagnosis can assist dentists and technicians to complete heavy and repeat work, change stomatology from subjective perception to objective science, and help to make diagnosis and treatment plan efficiently and accurately. This review briefly summarized related knowledge and development of machine learning and artificial neural network, its application status and existing problems in the field of segmentation and labelling of three-dimensional intraoral anatomical features, and provided an outlook of its future development.


Subject(s)
Artificial Intelligence , Machine Learning , Neural Networks, Computer
14.
Chinese Journal of Stomatology ; (12): 358-365, 2022.
Article in Chinese | WPRIM | ID: wpr-935875

ABSTRACT

Objective: To explore the establishment of an efficient and automatic method to determine anatomical landmarks in three-dimensional (3D) facial data, and to evaluate the effectiveness of this method in determining landmarks. Methods: A total of 30 male patients with tooth defect or dentition defect (with good facial symmetry) who visited the Department of Prosthodontics, Peking University School and Hospital of Stomatology from June to August 2021 were selected, and these participants' age was between 18-45 years. 3D facial data of patients was collected and the size normalization and overlap alignment were performed based on the Procrustes analysis algorithm. A 3D face average model was built in Geomagic Studio 2013 software, and a 3D face template was built through parametric processing. MeshLab 2020 software was used to determine the serial number information of 32 facial anatomical landmarks (10 midline landmarks and 22 bilateral landmarks). Five male patients with no mandibular deviation and 5 with mild mandibular deviation were selected from the Department of Orthodontics or Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June to August 2021. 3D facial data of patients was collected as test data. Based on the 3D face template and the serial number information of the facial anatomical landmarks, the coordinates of 32 facial anatomical landmarks on the test data were automatically determined with the help of the MeshMonk non-rigid registration algorithm program, as the data for the template method to determine the landmarks. The positions of 32 facial anatomical landmarks on the test data were manually determined by the same attending physician, and the coordinates of the landmarks were recorded as the data for determining landmarks by the expert method. Calculated the distance value of the coordinates of facial anatomical landmarks between the template method and the expert method, as the landmark localization error, and evaluated the effect of the template method in determining the landmarks. Results: For 5 patients with no mandibular deviation, the landmark localization error of all facial anatomical landmarks by template method was (1.65±1.19) mm, the landmark localization error of the midline facial anatomical landmarks was (1.19±0.45) mm, the landmark localization error of bilateral facial anatomical landmarks was (1.85±1.33) mm. For 5 patients with mild mandibular deviation, the landmark localization error of all facial anatomical landmarks by template method was (2.55±2.22) mm, the landmark localization error of the midline facial anatomical landmarks was (1.85±1.13) mm, the landmark localization error of bilateral facial anatomical landmarks was (2.87±2.45) mm. Conclusions: The automatic determination method of facial anatomical landmarks proposed in this study has certain feasibility, and the determination effect of midline facial anatomical landmarks is better than that of bilateral facial anatomical landmarks. The effect of determining facial anatomical landmarks in patients without mandibular deviation is better than that in patients with mild mandibular deviation.


Subject(s)
Adolescent , Adult , Algorithms , Anatomic Landmarks , Cephalometry/methods , Face/anatomy & histology , Female , Humans , Imaging, Three-Dimensional/methods , Male , Malocclusion , Middle Aged , Orthodontics , Software , Young Adult
15.
Chinese Journal of Stomatology ; (12): 162-167, 2022.
Article in Chinese | WPRIM | ID: wpr-935843

ABSTRACT

Objective: To evaluate the effect of adding a geometric feature on the accuracy of digital impressions obtained by intraoral scanners for implant restoration of edentulous jaw quantitatively. Methods: A dentiform model of the maxilla of completely edentulous arch with 6 implant analogs+scan bodies (No. 1-6) was selected as the reference model. Without geometric feature, the dentiform model was scanned by dental model scanner and repeated for 5 times as true value group. Before and after adding the geometric feature, the same operator used intraoral scanner A (Trios 3) and B (Aoralscan 2) to scan the dentiform model with the same scanning path. Each type of intraoral scanner scanned 10 times and ".stl " datas were obtained. The results were imported into reverse engineering software (Geomagic Studio 2015). The linear distances of center point of upper plane between sacn body 1 to 6 was calculated, denoted as D12, D13, D14, D15 and D16. Trueness was the absolute value subtracted from the measured value of the intraoral scanner groups and true value; precision was the absolute value of pairwise subtraction of the measured values in the intraoral scanner groups.The smaller the value, the better the accuracy or precision.With or without the feature, all scan data were statistically analyzed, and the effect of adding geometric feature on the trueness and precision of the two intraoral scanners were evaluated. Results: As for intraoral scanner A, with the feature in place, significant differences were found in D14, D15, D16 for tureness(t=2.66, 2.75, 2.95, P<0.05); the trueness for D16 decreased from (101.9±47.1) μm to (49.6±30.3) μm. On the other hand, with features on the edentulous area, the precision was significantly increased in D15 and D16 (U=378.00, 672.00, P<0.05); the precision for D15 decreased from 40.8 (45.1) μm to 13.1 (17.0) μm. As for intraoral scanner B, the trueness of D12, D13 and D14 after adding geometric features was significantly better than before (t=3.02, 2.66, U=22.00, P<0.05). With feature on the edentulous area, the trueness for D13 decreased from (116.6±41.2) μm to (70.8±35.5) μm. There was no statistical significance in the trueness of D15 and D16 with or without geometric feature (P>0.05), however, the precision of D15 and D16 after adding geometric feature was significantly better than before (U=702.00, 489.00,P<0.05). The precision of D16 decreased from 112.5 (124.7) μm to 35.9 (85.8) μm. Conclusions: The use of geometric feature in edentulous space improves the trueness and precision of the different principle intraoral scanners tested.


Subject(s)
Computer-Aided Design , Dental Implants , Dental Impression Technique , Imaging, Three-Dimensional , Models, Dental
16.
Chinese Journal of Epidemiology ; (12): 523-527, 2022.
Article in Chinese | WPRIM | ID: wpr-935421

ABSTRACT

Objective: To investigate the distribution of HIV-1 genetic subtypes and pretreatment drug resistance (PDR) among men who have sex with men (MSM) from 19 cities of 6 provinces in China. Methods: From April to November 2019, 574 plasma samples of ART-naive HIV-1 infected MSM were collected from 19 cities in Hebei, Shandong, Jiangsu, Zhejiang, Fujian, and Guangdong provinces, total ribonucleic acid (RNA) was extracted and amplified the HIV-1 pol gene region by nested polymerase chain reaction (PCR) after reverse transcription. Then sequences were used to construct a phylogenetic tree to determine genetic subtypes and submitted to the Stanford drug resistance database for drug resistance analysis. Results: A total of 479 samples were successfully amplified by PCR. The HIV-1 genetic subtypes included CRF01_AE, CRF07_BC, B, CRF55_01B, CRF59_01B, CRF65_cpx, CRF103_01B, CRF67_01B, CRF68_01B and unrecognized subtype, which accounted for 43.4%, 36.3%, 6.3%, 5.9%, 0.8%, 0.8%, 0.4%, 0.4%, 0.2% and 5.5%, respectively. The distribution of genetic subtypes among provinces is statistically different (χ2=44.141, P<0.001). The overall PDR rate was 4.6% (22/479), the drug resistance rate of non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, and protease inhibitors were 3.5% (17/479), 0.8% (4/479) and 0.2% (1/479), respectively. The PDR rate of recent infections was significantly higher than that of long-term infections (χ2=4.634, P=0.031). Conclusions: The HIV-1 genetic subtypes among MSM infected with HIV-1 from 19 cities of 6 provinces in China are diverse, and the distribution of subtypes is different among provinces. The overall PDR rate is low, while the PDR rate of recent infections was significantly higher than that of long-term infections, suggesting the surveillance of PDR in recent infections should be strengthened.


Subject(s)
China/epidemiology , Cities , Drug Resistance , Drug Resistance, Viral/genetics , Female , Genotype , HIV Infections/epidemiology , HIV Seropositivity/drug therapy , HIV-1/genetics , Homosexuality, Male , Humans , Male , Phylogeny , Reverse Transcriptase Inhibitors/therapeutic use , Sexual and Gender Minorities
17.
Article in Chinese | WPRIM | ID: wpr-933628

ABSTRACT

Objective:To investigate the effect of albumin to fibrinogen ratio on the prognosis of patients undergoing radical resection for colorectal cancer.Methods:Clinical and pathological data of 216 patients who underwent laparoscopic radical resection of colorectal cancer at the General Surgery Department of Taizhou People's Hospital from Aug 2015 to Jul 2017 were retrospectively analyzed. Albumin and fibrinogen results within 7 days before surgery was collected. The optimal cut-off point of AFR was determined by Youden index of ROC curve. Kaplan-Meier analysis, univariate and multivariate COX regression models were used to analyze the prognostic factors of OS and DFS.Results:The best postoperative OS threshold of AFR for patients undergoing laparoscopic radical resection of colorectal cancer was 9.43. Univariate analysis and multivariate COX regression analysis showed that age ≤65 years, TNM stage Ⅰ-Ⅱ, and AFR≥9.43 had better OS and DFS (all P<0.05). Conclusions:Preoperative AFR level had a good predictive value on postoperative survival of patients undergoing laparoscopic radical resection of colorectal cancer, and AFR<9.43 was an independent risk factor for postoperative OS and DFS.

18.
Chinese Journal of Orthopaedics ; (12): 618-625, 2022.
Article in Chinese | WPRIM | ID: wpr-932873

ABSTRACT

Objective:To explore the clinical features and treatment strategies of the transsyndesmotic ankle fracture dislocation.Methods:Data of 26 patients of transsyndesmotic ankle fracture dislocation who were treated in our hospital from December 2013 to November 2020 were retrospectively analyzed. There were 16 men and 10 women with an average age of 49.54±12.81 years (range, 26-68 years). Open injuries in 17 cases, of which the Gustilo-Anderson II type in 6 cases, IIIA type in 11 cases, closed injuries in 9 cases. According to the AO/OTA fracture classification, 44B type in 4 cases, 44C type in 22 cases. According to the Lauge-Hansen classification, there were 16 cases of pronation-abduction, 10 cases of pronation-external rotation, including 4 cases of Maisonneuve fractures, and of the 4 cases of Maisonneuve fractures, there were 3 cases of double Maisonneuve fracture. The talar dislocation was anterior, neutral, and posterior within the distal tibiofibular joint in 10 cases, 7 cases, and 9 cases. Fibular fractures in 26 cases, medial malleolar fractures in 24 cases, deltoid ligament rupture in 2 cases, posterior malleolar fractures in 13 cases, and anterior malleolar fractures in 8 cases. All closed injuries were closed reduction and plaster fixation and all open injuries were emergently debridement and reduced under the tibial plafond in the emergency department. Surgical treatment was taken until the soft tissue conditions to be allowed. The reduction quality was assessed by postoperative radiography according to the criteria proposed by Burwell-Charnley. The function of the ankle joint was assessed by the ankle-hindfoot rating system of the American Orthopaedic Foot and Ankle Society (AOFAS), and the posttraumatic arthritis and objectively quantified was assessed using the Kellgren-Lawrence grading scale.Results:There were 4 cases were unreduced due to the tibial posterior tendon to flip through the ankle joint and dislocate anterior to the tibia through the interosseous membrane. Stabilization of fibular fractures were achieved with plate in 25 cases. There were 24 cases of medial malleolar fractures, and the fixation were achieved with cannulated screws in 23 cases and with K-wire fixation in 1 case. There were 12 cases of posterior malleolar fractures treated with open reduction and internal fixation including cannulated screws in 9 cases and antiglide plates in 3 cases. There were 7 cases of anterior malleolar fractures treated with open reduction and internal fixation including suture anchors in 1 case and cannulated screws in 6 cases. Stabilization of syndesmosis was achieved with syndesmotic screws in 14 cases and with TightRope in 2 cases. All patients were followed up for 20.23±9.70 months (range, 12-60 months). According to the Burwell-Charnley criteria of reduction quality, anatomic reduction was obtained in 22 cases, and satisfactory reduction was gained in 4 cases. All fractures healed in 16.31±3.64 weeks (range, 10-24 weeks). Functional examination of the ankle joint (angle measurement method): dorsiflexion average angle 10.38°±6.66°, plantarflexion average angle 34.04°±7.20°. At latest follow up, the AOFAS score was 83.30±13.94 (range, 24-100). Ten (38%) of 26 patients had radiographic evidence of posttraumatic ankle arthritis. According to the Kellgren-Lawrence grading scale criteria, there were grade I in 5 cases, II in 2 cases, III in 2 cases, and IV in 1 case. 2 cases of wound dishence were recovered through changing dressing and 2 cases of skin necrosis were recovered by skin graft and flap transposition respectively. There were no significant complications such as infection, nonunion, or implant failure.Conclusion:The transsyndesmotic ankle fracture dislocation, represents an exceptional pattern of high-energy fractures with significant syndesmotic disruption, and potential soft tissue compromise. Careful attention to radiographic findings can identify unique fracture characteristics relative to operative decision-making. Tibialis posterior tendon dislocation, a rare complication in the transsyndesmotic ankle fracture dislocation injuries, can impede anatomical reduction of the ankle mortise. The open reduction and internal fixation may be an optimal approach to treat transsyndesmotic ankle fracture dislocation injuries. However, the rate of posttraumatic arthritis is relatively high.

19.
Article in Chinese | WPRIM | ID: wpr-932697

ABSTRACT

It is necessary to place bolus on skin to increase the surface dose when using high-energy rays to treat superficial lesions because of its build-up effect. It is well known that the set-up reproducibility of hand-made bolus is poor, and the main concern of commercialized bolus is the inadvertent air gap between the bolus and irregular skin. Owing to the advantage of making individualized and complex-shaped bolus, 3D-printing technology is playing an important role in making the bolus. The aim of this review is to summarize the current research status of hand-made, commercialized and 3D-printed bolus materials and future development trend of the bolus, providing reference for clinical application.

20.
Article in Chinese | WPRIM | ID: wpr-932559

ABSTRACT

Objective:To evaluate the effects of simultaneous integrated boost intensity-modulated radical radiotherapy (SIB-IMRT) on the long-term prognosis of patients with cervical and upper thoracic esophageal cancer.Methods:From January 2011 to December 2014, a retrospective analysis was performed in 172 patients with cervical and upper thoracic esophageal cancer who were eligible for IMRT. First, the prognosis of all the patients was evaluated using single factor and multivariate analyses. According to the different irradiation method of the patients, the patients were divided into two groups, one of which received conventional IMRT (C-IMRT) and the other of which received SIB-IMRT. Propensity score matching (PSM) analysis was applied to match the two groups of patients and to determine the treatment efficacy of patients after PSM, prognostic factors, failure modes, and side effects. SPSS19.0 statistical software was used to conduct statistical analysis.Results:The median overall survival (OS) and progression-free survival (PFS) times of all the patients were 30 months and 20 months, respectively. The fact whether the surrounding tissues and organs of esophageal lesions were invaded, clinical node staging (cN staging), chemotherapy, and GTV-maximum transverse diameter were observed to be independent influencing factors of OS and PFS in all the patients ( P<0.001, P=0.013, 0.005, 0.002; P<0.001, P=0.017, 0.034, 0.002). In addition, the independent influencing factors of PFS showed short-term efficacy ( P=0.036). After PSM, there were 54 patients in each of the two groups. The result of multivariate analysis showed that the fact whether the surrounding tissues and organs of esophageal lesions were invaded, cN staging, cTNM staging, prescribed dose, GTV-maximum transverse diameter, and irradiation method were independent factors affecting the OS ( P<0.001, P=0.008, 0.014, 0.021, 0.010, 0.008). Similarly, the fact whether the surrounding tissues and organs of esophageal lesions were invaded, cN staging, and GTV-maximum transverse diameter were observed to be independent factors that affect the PFS of patients ( P<0.001, P=0.044, 0.013). The difference in the total failure rate (70.4% vs. 50.0%) and the local regional recurrence rate (61.1% vs. 31.5%) between the C-IMRT and SIB-IMRT groups after treatment was significant ( χ2=4.68, 9.53, P=0.031, 0.002). The incidence of radiation pneumonitis of grade ≥ 1 in the C-IMRT group was significantly higher than that of the SIB-IMRT group ( χ2=6.16, P=0.046), whereas the leukocyte suppression of grade ≥ 2 in the C-IMRT group was significantly lower than that in the SIB-IMRT group ( χ2=12.77, P=0.005). Conclusions:As shown by the result of this study, compared with C-IMRT, SIB-IMRT can improve the OS of patients with cervical and upper thoracic esophageal cancer to a certain extent. Whether SIB-IMRT can improve the PFS of patients requires further research.

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