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1.
文章 在 中文 | WPRIM | ID: wpr-1021605

摘要

BACKGROUND:Myocardial patches are used as an effective way to repair damaged myocardium,and there is controversy over which cells to use to make myocardial patches and how to maximize the therapeutic effect of myocardial patches in vivo. OBJECTIVE:To find out the best way to make myocardial patches by overviewing the cellular sources of myocardial patches and strategies for perfecting them. METHODS:The first author searched PubMed and Web of Science databases by using"cell sheet,cell patch,cardiomyocytes,cardiac progenitor cells,fibroblasts,embryonic stem cell,mesenchymal stem cells"as English search terms,and searched CNKI and Wanfang databases by using"myocardial patch,biological 3D printing,myocardial"as Chinese search terms.After enrollment screening,94 articles were ultimately included in the result analysis. RESULTS AND CONCLUSION:(1)The cellular sources of myocardial patches are mainly divided into three categories:somatic cells,monoenergetic stem cells,and pluripotent stem cells,respectively.There are rich sources of cells for myocardial patches,but not all of them are suitable for making myocardial patches,e.g.,myocardial patches made from fibroblasts and skeletal myoblasts carry a risk of arrhythmogenicity,and mesenchymal stem cells have a short in vivo duration of action and ethical concerns.With the discovery of induced multifunctional stem cells,a reliable source of cells for making myocardial patches is available.(2)There are two methods of making myocardial patches.One is using cell sheet technology.The other is using biological 3D printing technology.Cell sheet technology can preserve the extracellular matrix components intact and can maximally mimic the cell growth ring in vivo.However,it is still difficult to obtain myocardial patches with three-dimensional structure by cell sheet technology.Biologicasl 3D printing technology,however,can be used to obtain myocardial patches with three-dimensional structures through computerized personalized design.(3)The strategies for perfecting myocardial patches mainly include:making myocardial patches after co-cultivation of multiple cells,improving the ink formulation and scaffold composition in biological 3D printing technology,improving the therapeutic effect of myocardial patches,suppressing immune rejection after transplantation,and perfecting the differentiation and cultivation protocols of stem cells.(4)There is no optimal cell source or method for making myocardial patches,and myocardial patches obtained from a particular cell or technique alone often do not achieve the desired therapeutic effect.Therefore,researchers need to choose the appropriate strategy for making myocardial patches based on the desired therapeutic effect before making them.

2.
文章 在 中文 | WPRIM | ID: wpr-986048

摘要

Objective: To investigate the effects of duration, temperature and shake on paraquat (PQ) concentration in the blood of PQ-exposed rats during the specinen preservation and transportation. Methods: In March 2021, 60 SD male rats of Specific Pathogen Free class were randomly divided into low-dose group (10 mg/kg PQ) and high-dose group (80 mg/kg PQ). Each group was divided into 5 subgroups (normal temperature group, cold storage group, 37 ℃ storage group, shaking on normal temperature group and shaking on 37 ℃ group), six rats in each subgroup. The rats were given intraperitoneal injection of PQ, 1 h after exposure, the blood samples were obtained by cardiac extraction. After different interventions, the concentrations of PQ were detected and compared before and after the intervention in each subgroup. Results: In the shaking on 37 ℃ group, the results of PQ concentrations in PQ-exposed rats were significantly lower than those before the intervention (P<0.05). In the other subgroups, the results were not significantly different compared with before intervention (P>0.05) . Conclusion: The concentration of PQ in the blood of rats exposed to PQ was decreased by shaking for 4 hours at 37 ℃.


Subject(s)
Rats , Male , Animals , Rats, Sprague-Dawley , Paraquat/pharmacology , Lung
3.
文章 在 中文 | WPRIM | ID: wpr-1045899

摘要

This article uses the "behavioural and social drivers of vaccination" model released by the World Health Organization (WHO) in 2022 to analyze influenza vaccine policy documents issued by the state and governments. This indicates that the current influenza vaccination policy in China has paid some attention to "publicity and mobilization", but it still pays insufficient attention to "vaccination convenience". It is recommended to continue to strengthen publicity and mobilization, explore ways to improve the convenience of vaccination, formulate corresponding plans to improve the convenience of vaccination, scientifically set vaccination rate targets, and encourage areas with conditions to carry out free vaccination projects for key populations.

4.
文章 在 中文 | WPRIM | ID: wpr-1046222

摘要

This article uses the "behavioural and social drivers of vaccination" model released by the World Health Organization (WHO) in 2022 to analyze influenza vaccine policy documents issued by the state and governments. This indicates that the current influenza vaccination policy in China has paid some attention to "publicity and mobilization", but it still pays insufficient attention to "vaccination convenience". It is recommended to continue to strengthen publicity and mobilization, explore ways to improve the convenience of vaccination, formulate corresponding plans to improve the convenience of vaccination, scientifically set vaccination rate targets, and encourage areas with conditions to carry out free vaccination projects for key populations.

5.
Chinese Journal of Epidemiology ; (12): 183-188, 2022.
文章 在 中文 | WPRIM | ID: wpr-935368

摘要

Objective: To analyze the time distribution of the first positive nucleic acid detection in imported cases infected with SARS-CoV-2 reported nationwide in China and provide references for further improvement of the prevention and control of COVID-19 in international travelers. Methods: The data of imported cases infected with SARS-CoV-2 reported by provinces from 24 July 2020 and 23 July 2021 were collected for the analysis on the time distribution of the first positive nucleic acid detection after entering China. Results: A total of 7 199 imported cases infected with SARS-CoV-2 were reported in 28 provinces during 24 July 2020 to 23 July 2021. The median interval (Q1, Q3) from the entry to the first positive nucleic acid detection of SARS-CoV-2 was 1 (0, 5) day. The imported cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry accounted for 95.15% (6 850/7 199) and 4.85% (349/7 199) respectively. Among these cases, 3.65% (263/7 199), 0.88% (63/7 199) and 0.32% (23/7 199) had the first positive nucleic acid detections within 15-21 days, 22-28 days and 28 days later after the entry respectively. The proportion of asymptomatic infections were 47.24% (3 236/6 850) and 63.61% (222/349) among the cases who had the first positive nucleic acid detections within 14 days and 14 days later after the entry respectively. A total of 39.54% (138/349) of cases infected with SARS-CoV-2 with the first positive nucleic acid detections 14 days later after the entry had inter-provincial travel after the discharge of entry point isolation. Conclusions: About 5% of the imported cases infected with SARS-CoV-2 were first positive 14 days later after the entry. In order to effectively reduce the risk of domestic COVID-19 secondary outbreaks caused by imported cases, it is suggested to add a nucleic acid test on 8th -13th day after the entry.


Subject(s)
Humans , Asymptomatic Infections , COVID-19 , China/epidemiology , Nucleic Acids , SARS-CoV-2
6.
文章 在 英语 | WPRIM | ID: wpr-939587

摘要

Objectives@#Hand, foot and mouth disease (HFMD) is a widespread infectious disease that causes a significant disease burden on society. To achieve early intervention and to prevent outbreaks of disease, we propose a novel warning model that can accurately predict the incidence of HFMD.@*Methods@#We propose a spatial-temporal graph convolutional network (STGCN) that combines spatial factors for surrounding cities with historical incidence over a certain time period to predict the future occurrence of HFMD in Guangdong and Shandong between 2011 and 2019. The 2011-2018 data served as the training and verification set, while data from 2019 served as the prediction set. Six important parameters were selected and verified in this model and the deviation was displayed by the root mean square error and the mean absolute error.@*Results@#As the first application using a STGCN for disease forecasting, we succeeded in accurately predicting the incidence of HFMD over a 12-week period at the prefecture level, especially for cities of significant concern.@*Conclusions@#This model provides a novel approach for infectious disease prediction and may help health administrative departments implement effective control measures up to 3 months in advance, which may significantly reduce the morbidity associated with HFMD in the future.


Subject(s)
Humans , China/epidemiology , Cities/epidemiology , Data Visualization , Disease Outbreaks/statistics & numerical data , Forecasting/methods , Hand, Foot and Mouth Disease/prevention & control , Incidence , Neural Networks, Computer , Reproducibility of Results , Spatio-Temporal Analysis , Time Factors
7.
文章 在 中文 | WPRIM | ID: wpr-942227

摘要

OBJECTIVE@#To construct a preoperative evaluation system for partial nephrectomy using CT three-dimensional visualization technology and to explore its practical value.@*METHODS@#The clinical data of the patients who underwent partial nephrectomy for renal tumors in Department of Urology, Peking University First Hospital were collected retrospectively. At the same time, the homogenized standard data of patients who underwent partial nephrectomy for renal tumors were collected in 16 clinical centers in China. The CT three-dimensional visualization system was applied (IPS system, Yorktal) to evaluate tumor anatomy, blood supply, perirenal fat and other information. The parameters were summarized to build a three-dimensional nephrometry system, on the basis of which virtual surgery design and intraoperative navigation were completed.@*RESULTS@#A three-dimensional visualization image was established based on the enhanced CT urography. The nephrometry system included the longest diameter and volume of the tumor, proportion volume of tumor invading the parenchyma, maximum depth of the tumor invading the parenchyma, contact surface area, flatness of the tumor surface, renal segment where the tumor was located, vascular variation, and perirenal fat. The average two-dimensional diameter of the tumor was (2.78±1.43) cm, the average three-dimensional maximum diameter was (3.09±1.35) cm, and the average postoperative pathological size was (3.01±1.38) cm. The maximum tumor diameter in the three-dimensional image was significantly related to the prolonged renal artery clamping time and intra-operative blood loss (r=0.502, P=0.020; r=0.403, P=0.046). The three-dimensional and pathological tumor volume were (25.7±48.4) cm3 and (33.0±36.4) cm3, respectively (P=0.229). The tumor volume was significantly related to the intraoperative blood loss (r=0.660, P < 0.001). The proportion volume of the tumor invading into renal parenchyma was significantly related to the prolongation of renal artery clamping and the occurrence of postoperative complications (r=0.410, P=0.041; r=0.587, P=0.005). The tumor contact surface area and the presence of vascular variation did not show correlation with the perioperative data and postoperative complications. While the preoperative evaluation was completed, the reconstructed three-dimensional image could be zoomed, rotated, combined display, color adjustment, transparency, and simulated cutting on the Touch Viewer system. The process generally consisted of showing or hiding the tissue, adjusting the transparency of the interested area, rotating and zooming the image to match the position of the surgical patient. Together, these functions met the requirements of preoperative virtual surgery plan and intraoperative auxiliary navigation.@*CONCLUSION@#Three-dimensional images can provide a more intuitive anatomical structure. The CT three-dimensional visua-lization system clearly displays tumor anatomical parameters, blood supply and perirenal fat. The three-dimensional nephrometry system for renal tumors can help predict the difficulty of partial nephrectomy and perioperative complications. Importing the reconstructed three-dimensional visualization image into the specified program or robot operating system can complete virtual surgery and intraoperative navigation, helping the surgeon to better grasp the surgical process. The indexes included in the nephrometry system and the score weights of each index need to be confirmed and perfected by multi-center study with large samples.


Subject(s)
Humans , China , Kidney/surgery , Kidney Neoplasms/surgery , Laparoscopy , Nephrectomy , Retrospective Studies
8.
Chinese Pharmacological Bulletin ; (12): 490-497, 2021.
文章 在 中文 | WPRIM | ID: wpr-1014388

摘要

Aim To investigate the role of Nampt in regulating ERK1/2 in cardiac hypertrophy and its mechanisms. Methods The primary neonatal rat cardiomyocytes were stimulated by phenylephrine (PE) (100 μmol · L

9.
Journal of Experimental Hematology ; (6): 1266-1270, 2021.
文章 在 中文 | WPRIM | ID: wpr-888550

摘要

OBJECTIVE@#To analyze the genotypes and distribution of thalassemia in children in Quanzhou Region so as to provide reference for the prevention and control of thalassemia.@*METHODS@#A total of 1 302 children with suspected thalassemia were collected from January 2014 to April 2020 in Quanzhou Region. The deletional α-thalassemia was detected by Gap-PCR, and DNA reverse dot blot (RDB) hybridization was used to detect α- and β-thalassemia mutations.@*RESULTS@#In the 1 302 cases, 667 cases were identified as thalassemia carriers, and the positive detection rate was about 51.23%. Among them, 380 cases of α-thalassemia gene were detected, and --@*CONCLUSION@#There are various genotypes of thalassemia in children in Quanzhou Region, and many children with thalassemia major or intermedia. Therefore, further prevention and control of thalassemia need to be strengthened for reducing the birth of thalassemia major or intermedia.


Subject(s)
Child , Humans , China , Genetic Testing , Genotype , Heterozygote , Mutation , alpha-Thalassemia/genetics , beta-Thalassemia/genetics
10.
Journal of Experimental Hematology ; (6): 1256-1260, 2020.
文章 在 中文 | WPRIM | ID: wpr-827130

摘要

OBJECTIVE@#To explore the effect of miR-144 to the biological behavior of multiple myeloma cells and its mechanism.@*METHODS@#RT-PCR was used to detect the expression of miR-144 in multiple myeloma cells and plasma of MM patients. MTT assay was used to detect the proliferation and cloning ability of myeloma cells transfected by miR-144. Flow cytometry was used to detect the cell cycle distribution of myeloma cells with over-expression of miR-144. Apoptosis of myeloma cells with over-expression of miR-144 was detected by TUNEL assay. Transwell cell invasion and migration assay was used to detect the invasion and migration ability of myeloma cells with overexpressing on miR-144.Western blot analysis was used to detect the protein expression levels of MMP-9 and MMP-2 in myeloma cells with over expression of miR-144, as well as the expression levels of proteins related to Wnt/β-catenin signaling pathway.@*RESULTS@#The expression level of miR-144 in MM cell lines and blood of MM patients was significantly lower than that in control group (P<0.05). The proliferation, invasion and migration of myeloma cells with over-expression of miR-144 were significantly decreased (P<0.05), and the apoptosis level was increased (P<0.05). The expression levels of MMP-9, MMP-2, Wnt/β-catenin signaling pathway in myeloma cells with over-expression of miR-144 were significantly lower than those in control group (P<0.05).@*CONCLUSION@#MiR-144 can inhibit the proliferation, migration and invasion of multiple myeloma cells and induce cell apoptosis. The specific mechanism may be related with the activity of inhibiting Wnt/β-catenin signaling pathway.


Subject(s)
Humans , Apoptosis , Biological Products , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , MicroRNAs , Multiple Myeloma , Wnt Signaling Pathway , Wnt4 Protein , beta Catenin
11.
Chinese Medical Journal ; (24): 1390-1396, 2020.
文章 在 英语 | WPRIM | ID: wpr-827665

摘要

BACKGROUND@#Critical patients with the coronavirus disease 2019 (COVID-19), even those whose nucleic acid test results had turned negative and those receiving maximal medical support, have been noted to progress to irreversible fatal respiratory failure. Lung transplantation (LT) as the sole therapy for end-stage pulmonary fibrosis related to acute respiratory distress syndrome has been considered as the ultimate rescue therapy for these patients.@*METHODS@#From February 10 to March 10, 2020, three male patients were urgently assessed and listed for transplantation. After conducting a full ethical review and after obtaining assent from the family of the patients, we performed three LT procedures for COVID-19 patients with illness durations of more than one month and extremely high sequential organ failure assessment scores.@*RESULTS@#Two of the three recipients survived post-LT and started participating in a rehabilitation program. Pearls of the LT team collaboration and perioperative logistics were summarized and continually improved. The pathological results of the explanted lungs were concordant with the critical clinical manifestation, and provided insight towards better understanding of the disease. Government health affair systems, virology detection tools, and modern communication technology all play key roles towards the survival of the patients and their rehabilitation.@*CONCLUSIONS@#LT can be performed in end-stage patients with respiratory failure due to COVID-19-related pulmonary fibrosis. If confirmed positive-turned-negative virology status without organ dysfunction that could contraindicate LT, LT provided the final option for these patients to avoid certain death, with proper protection of transplant surgeons and medical staffs. By ensuring instant seamless care for both patients and medical teams, the goal of reducing the mortality rate and salvaging the lives of patients with COVID-19 can be attained.


Subject(s)
Aged , Humans , Male , Middle Aged , Betacoronavirus , Coronavirus Infections , Mortality , Extracorporeal Membrane Oxygenation , Lung Transplantation , Methods , Pandemics , Pneumonia, Viral , Mortality , Pulmonary Fibrosis , Mortality , General Surgery , Respiratory Distress Syndrome , Mortality , General Surgery
12.
文章 在 英语 | WPRIM | ID: wpr-827782

摘要

A series of novel pyrano[2, 3-d]trizaole compounds were synthesized and their α-glucosidase inhibitory activities were evaluated by in vitro enzyme assay. The experimental data demonstrated that compound 10f showed up to 10-fold higher inhibition (IC74.0 ± 1.3 μmol·L) than acarbose. The molecular docking revealed that compound 10f could bind to α-glucosidase via the hydrophobic, π-π stacking, and hydrogen bonding interactions. The results may benefit further structural modifications to find new and potent α-glucosidase inhibitors.

13.
文章 在 中文 | WPRIM | ID: wpr-802345

摘要

Objective:To investigate the effect of Whenshen prescription on hepatic encephalopathy in patients with HBV-related hepatic cirrhosis and kidney Yang deficiency syndrome and the content of high-mobility group protein B1 (HMGB1) and Toll-like receptor 4 (TLR4). Method:The 66 patients treated in the Hospital of Chengdu University of Traditional Chinese Medicine from August 2013 to January 2015 were included. A prospective, parallel controlled design was used. The 66 cases were randomly divided into treatment group and control group according to 1:1 ratio, with 33 cases in each group.The control group was treated with comprehensive therapy, colon dialysis and placebo enema, while treatment group was treated with comprehensive therapy, colon dialysis and Whenshen prescription enema for 10 days. Finally, liver function, number connect test (NCT), digit-symbol test (SDT), awake time, the total effective rate and content of HMGB1 and TLR4 were analyzed. Result:There was no significant difference between two groups at baseline. The total effective rate in treatment group was 93.9%, which was higher than 72.7% in control group (PP1 and TLR4 in treatment group were lower than those in the control group. Conclusion:Whenshen prescription can significantly improve the clinical efficacy by inhibiting the contents of HMGB1 and TLR4.

14.
文章 在 中文 | WPRIM | ID: wpr-781664

摘要

To investigate the value of diffusion-weighted imaging(DWI)and apparent diffusion coefficient(ADC)in the diagnosis and differential diagnosis of posterior fossa solid hemangioblastoma(PFSH). We retrospectively analyzed the clinical data of 15 PFSH patients and 58 patients with other hypervascular tumors in the posterior fossa(the latter included 23 cases of meningioma,5 cases of medulloblastoma,8 cases of acoustic neuroma,4 cases of hemangiopericytoma,5 cases of lymphoma,9 cases of metastatic tumor,3 cases of astrocytoma,and 1 case of choroid plexus papilloma)confirmed by operation and pathology.All patients underwent axial DWI scans,and the mean ADC value of solid part of the tumors and the adjacent normal cerebellar white matter were measured,and then the normalized ADC was calculated.In addition, test was used to compare the differences in mean ADC and normalized ADC between these two groups,and receiver operating characteristic(ROC)curve was applied to analyze the diagnostic performance of normalized ADC. Of all the 15 PFSH patients,DWI appeared hypointense in 12 patients and isointense in 3 patients;the signals on ADC maps were isointense or hyperintense;the mean ADC value of PFSHs was(1.881±0.445)×10 mm /s and the normalized ADC was 2.70±0.62.In contrast,in 58 patients with other tumors in the posterior fossa,DWI appeared hyperintense in 51 cases,isointense in 3 cases,and hypointense in 4 cases;the mean ADC value was(0.771±0.202)×10 mm /s,and the normalized ADC was 1.17±0.33.Thus,the ADC value and normalized ADC value were significantly higher in PFSH than in other tumors in the posterior fossa(=9.419,<0.001;=9.184,<0.001).The cut-off value of the normalized ADC for the diagnosis of solid hemangioblastoma was 1.89,with the sensitivity and specificity being 100%and 96.6%respectively,and the area under the ROC curve was 0.989. ADC and normalized ADC are valuable in the differential diagnosis of PFSH from other tumors with abundant blood supply.


Subject(s)
Humans , Diagnosis, Differential , Diffusion Magnetic Resonance Imaging , Hemangioblastoma , Diagnosis , ROC Curve , Retrospective Studies
15.
Chinese Medical Journal ; (24): 2783-2789, 2019.
文章 在 英语 | WPRIM | ID: wpr-781743

摘要

BACKGROUND@#Lung transplantation (LT) has been demonstrated as the only effective therapy for patients with end-stage lung diseases. Increasing listed lung transplant candidates and expanding volumes of lung transplant centers across China require well-organized programs and registry data collection based on the large population. This study aimed to summarize and analyze the data of LT development in China.@*METHODS@#We retrospectively collected and analyzed data from the China Lung Transplantation Registry (CLuTR). Key data were reported from the registry with transplant types, indications, donor and recipient characteristics, outcomes and survival. The survival Grade 0), renal insufficiency (estimated glomerular filtration rate <60 mL·min·1.73 m), were independently associated with a higher risk for 3-year mortality in the entire cohort.@*CONCLUSIONS@#Facing more end-stage of lung diseases and comorbidities, this study analyzed the outcomes and survival of LT recipients in China. Further prospectively stratified analyses with longer follow-up will be needed.

16.
文章 在 中文 | WPRIM | ID: wpr-687380

摘要

Combined use of drugs is a hot spot in the research of new drugs nowadays, and traditional Chinese medicine (TCM) is a classic practice in the combined use of drugs. In this paper, the compatibility of TCM prescriptions and the related properties of composed herbs were calculated and studied to verify and discuss the feasibility of the results in guiding compatibility. Research Group on New Drug Design, Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences had established a structured database of TCM prescriptions by using traditional Chinese medicine inheritance support system (TCMISS V2.0), including 4 012 prescription compatibilities, 2 072 drug components, 381 kinds of TCM diseases, 316 kinds of TCM syndromes and 26 kinds of drug properties. On the basis of the created database above, Support Vector Machine (SVM) was used to analyze the prescription compatibility data and establish a model for predicting feasibility of drug compatibilities. Analytic Hierarchy Process (AHP) and cluster analysis were used to study the influence of drug properties in the rationality of prescription compatibility. The computational results showed that the accuracy in efficacy prediction of two data sets, i.e. prescription-disease and prescription-syndrome, was up to 90% in the linear SVM model. The macro₋averaging and micro₋averaging of the two models were around 0.92, 0.46, respectively. After AHP mapping, most of the incompatible combinations showed significant difference with other drug combinations during the clustering process in the vertical icicle, indicating that the proper machine learning algorithm can be used to lay the foundation for further exploring the combination rules in TCM and establishing more detailed drug-disease and syndrome predicting models, and provide theoretical guidance for the study of the combined use of drugs to a certain degree.

17.
文章 在 中文 | WPRIM | ID: wpr-751916

摘要

Objective To analyze the problems and reasons in the clinical medicine postgraduate cultivation.We stated the competency of clinical medicine postgraduates according to the transition of health demands global medical development and practical requirements for clinical personnel. Me thods Questionnaire surveys combined with interviews were conducted, and statistical analysis was performed. In the first part, we selected the permanent staff with qualifications of medical clinicians, including: chief physicians, associate chief physicians, physicians, residents, accounting for 72% of the interviewees; And related personnel, including nurses, administrators and patients, were also interviewed, accounting for 28% of the total. 90 questionnaires were distributed, and 86 valid questionnaires were recovered, with an effective rate of 95.56%. In the second part, graduate students with clinical professional degrees were selected for interviews, 96 questionnaires were distributed, and 92 valid questionnaires were collected, and the effective rate was 95.83%.Re s ults There was a certain gap between the expected goal and the actual situation of the post competency of clinical professional degree graduate students, and the gap had a certain statistical significance. The clinical professional degree graduate students paid more attention to the doctor-patient communication, teamwork. Conclus ions We elaborated the required post competence for clinical medicine postgraduates on the basis of its content and characteristic. We propose to strengthen the cultivation of clinical medicine postgraduates by the reform and support of the government enhanced construction of teachers improved course plan and cultivation process perfected assessment system in order to make the students competent to their posts.

18.
文章 在 英语 | WPRIM | ID: wpr-772768

摘要

Excessive forces may cause root resorption and insufficient forces would introduce no effect in orthodontics. The objective of this study was to investigate the optimal orthodontic forces on a maxillary canine, using hydrostatic stress and logarithmic strain of the periodontal ligament (PDL) as indicators. Finite element models of a maxillary canine and surrounding tissues were developed. Distal translation/tipping forces, labial translation/tipping forces, and extrusion forces ranging from 0 to 300 g (100 g=0.98 N) were applied to the canine, as well as the force moment around the canine long axis ranging from 0 to 300 g·mm. The stress/strain of the PDL was quantified by nonlinear finite element analysis, and an absolute stress range between 0.47 kPa (capillary pressure) and 12.8 kPa (80% of human systolic blood pressure) was considered to be optimal, whereas an absolute strain exceeding 0.24% (80% of peak strain during canine maximal moving velocity) was considered optimal strain. The stress/strain distributions within the PDL were acquired for various canine movements, and the optimal orthodontic forces were calculated. As a result the optimal tipping forces (40-44 g for distal-direction and 28-32 g for labial-direction) were smaller than the translation forces (130-137 g for distal-direction and 110-124 g for labial-direction). In addition, the optimal forces for labial-direction motion (110-124 g for translation and 28-32 g for tipping) were smaller than those for distal-direction motion (130-137 g for translation and 40-44 g for tipping). Compared with previous results, the force interval was smaller than before and was therefore more conducive to the guidance of clinical treatment. The finite element analysis results provide new insights into orthodontic biomechanics and could help to optimize orthodontic treatment plans.


Subject(s)
Humans , Biomechanical Phenomena , Computer Simulation , Cuspid , Physiology , Models, Dental , Finite Element Analysis , Imaging, Three-Dimensional , Maxilla , Orthodontic Friction , Physiology , Periodontal Ligament , Physiology , Rotation , Stress, Mechanical , Tooth Movement Techniques
19.
Chinese Medical Journal ; (24): 2938-2946, 2018.
文章 在 英语 | WPRIM | ID: wpr-772890

摘要

Background@#Decision-making concerning the treatment of choroid plexus tumor (CPT) in pediatric patients remains a topic of considerable debate. The aim of this work was to describe clinical features and prognostic risk factors of CPT in the pediatric population and to provide theoretical opinions regarding clinical decisions for CPT.@*Methods@#The data of 96 patients with CPT and younger than 14 years were retrospectively analyzed. Clinical characteristics such as pathological type of CPTs, rate and severity of hydrocephalus, treatment and outcome, and recurrence were investigated. For categorical variables, the Pearson's Chi-square test was performed. The Mann-Whitney U-test was used for comparisons between nonnormally distributed parameters. Log-rank test was used for progression-free survival (PFS).@*Results@#The study included 70 choroid plexus papilloma (CPP) cases, 17 atypical choroid plexus papilloma (aCPP) cases, and 9 choroid plexus carcinoma (CPC) cases. Compared with patients with CPP or aCPP, patients with CPC had a shorter disease course (median: CPP, 4 months; aCPP, 2 months; CPC, 1 month; H: 23.5, P 0.05). Patients with CPC experienced shorter time for recurrence than those with CPP or aCPP (χ = 40.1, P < 0.0001).@*Conclusions@#Our results indicated that CPP in the fourth ventricle could trigger serious clinical symptoms at an early stage, requiring early intervention. Adjuvant treatment might be necessary for patients with partially resected CPP, aCPP, and CPC to achieve a favorable outcome.


Subject(s)
Child , Child, Preschool , Female , Humans , Infant , Male , Choroid Plexus Neoplasms , Mortality , Pathology , General Surgery , Hydrocephalus , Neoplasm Metastasis , Neoplasm Recurrence, Local , Prognosis , Risk Factors
20.
文章 在 中文 | WPRIM | ID: wpr-690449

摘要

<p><b>OBJECTIVE</b>To study the effects of intrahippocampal injection of cellular prion protein (PrP) antibody on cognitive deficits of APPswe/PSEN1 transgenic mice.</p><p><b>METHODS</b>Eight-month-old male APPswe/PSEN1 transgenic mice were subjected to bilateral intrahippocampal injection of a single dose (2 µL) of anti-PrP monoclonal antibody (EP1802Y) or PBS, with wild-type C57Bl/6J mice serving as the control group. After two months, the mice were tested for cognitive behaviors using open filed (OF) test, Morris water maze (MWM) test, fear conditioning (FC) test, and novel object recognition (NOR) test, and immunohistochemistry was used to examine the changes in hippocampal expression of Aβ.</p><p><b>RESULTS</b>The EP1802Y-treated and PBS-treated mice showed no significantly differences in the performance in OF test in terms of central activity time or total distance of activity (P>0.05), nor in NOR test in terms of novel object recognition index (P>0.05). In MWM test, the EP1802Y-treated and PBS-treated mice showed significantly reduced crossings of the hidden platform as compared with the wild-type mice (P<0.05), but EP1802Y-treated mice had a significantly shorter swimming distance to find the platform than PBS-treated mice (P<0.05). No significant differences were found in the results of FC test among the 3 groups. Immunohistochemistry revealed a significantly reduced expression of Aβ in the hippocampus of EP1802Y-treated mice.</p><p><b>CONCLUSION</b>Intrahippocampal injection of PrP antibody can improve cognitive deficits of APPswe/PSEN1 transgenic mice, which sheds light on a novel therapeutic approach for Alzheimer's disease that targets PrP to lower the toxicity of Aβ oligomer.</p>

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