1.Three-dimensional finite element initial analysis on the structure defect restoration of mandibular first molar under static and impact loads.
Li-li TAIN ; Wei LIANG ; Ling-min LI ; Han-chao MAI
West China Journal of Stomatology 2007;25(6):595-602
OBJECTIVETo make a mechanical analysis on three-dimensional finite element models of the mandibular first molar with the maximum distal occlusal (DO) structure defect after the root canal therapy and filling and crown restoration under static and impact loads and to provide a guideline for planning restoration for the clinic.
METHODSThe research adopted reverse engineering technology to build the model of three-dimensional finite element. The form of the intercuspal occlusion and cusp to cusp occlusion during the circulation of posterior teeth occlusion movement were simulated. Half-sine pulse/impact was chosen for the impact dynamic. The impact ratio was indicated to the stress change between impact loads and static loads.
RESULTSUnder the two kinds of loads, the maximum Mohr stress values of the metal crowns were shown in all models. The restoration effects between the two kinds of models were compared, the maximum Mohr stress value of the crown metal and dentin was not obviously difference. The maximum Mohr stress values of dentin were all obviously smaller than the stretch limit strength of dentin. The impact ratio closed to 1.
CONCLUSIONThe impact loads accorded with the oral actual situation more than the static loads, but the suitable analysis of the static loads could be accepted. The restoration of metal crown is necessary. The effects between the amalgam filling and full crown restoration and composite resin filling and full crown restoration is not difference obviously.
Composite Resins ; Crowns ; Dentin ; Finite Element Analysis ; Humans ; Molar
2.Protective Effects of Cornus Officinalis Total Glycosides and Cornus Polysaccharides on Myocardial Mitochondria of Acute Myocardial Infarction Rats: an Experimental Study.
Dan CHEN ; Jian-jun LI ; Li-ting ZHANG ; Wei KUANG ; Ke-fang CHEN ; Xiang-ping HOU ; Hua-chao MAI ; Ke CHEN
Chinese Journal of Integrated Traditional and Western Medicine 2015;35(9):1090-1098
OBJECTIVETo observe the effect of Cornus Officinalis total glycosides (COTG) and Cornus polysaccharides (CP) on myocardial mitochondria and expression levels of glycogen synthase kinase-3β (GSK-3β) of acute myocardial infarction (AMI) rats.
METHODSThe AMI rat model was established by ligating the left anterior descending branch of coronary artery. Rats were divided into 5 groups according to random digit table, i.e., the sham-operation group, the model group, the COTG prevention group, the CP treatment group, the COTG treatment group, 12 in each group. Normal saline was administered to rats in the normal control group and the model group by gastrogavage. Corresponding medication was respectively administered to rats in the rest 3 groups by gastrogavage. The cardiac function was detected by echocardiography and hemodynamics. The infarct size was determined by Masson trichrome staining. The expression of mitochondrial biogenesis genes such as a subunit of peroxisome proliferators-activated receptor-γ coactivator-1 (PGC-1α), PGC-1β, nuclear respiratory factor-1 (NRF-1), and GSK-3P mRNA were detected by Real-time PCR.
RESULTSCompared with the sham-operation group, the myocardial infarction size increased, cardiac function decreased, the expression of PGC-1α, PGC-1β, and NRF-1 mRNA decreased, and the expression of GSK-3β mRNA increased (all P <0. 05). Compared with the model group, myocardial infarction sizes were reduced, cardiac function was improved, the expression of NRF-1 mRNA was elevated in the COTG prevention group, the CP treatment group, the COTG treatment group; the expression of the PGC-1α and PGC-1β mRNA was elevated in the COTG prevention group and the CP treatment group; the expression of GSK-3β mRNA was reduced in the CP treatment group (all P <0. 05). Compared with the CP prevention group, fractional shortening (FS) and aortic systolic blood pressure (SBP) increased in the CP treatment group; ejection fraction (EF) decreased in the CP treatment group; the expression of PGC-1α, PGC-1β, NRF-1 mRNA were reduced in the the CP treatment group and the COTG treatment group; the expression of GSK-3β mRNA decreased in the CP treatment group (all P <0. 05). Compared with the COTG treatment group, FS, EF, left ventricular end systolic pressure (LVESP), SBP, and the expression of GSK-3β mRNA were reduced in the CP treatment group (P <0. 05).
CONCLUSIONSCOTG and CP could improve cardiac function, reduce the myocardial infarction area, and promote biogenesis of myocardial mitochondria. Their protective effects on the mitochondria of cadiocytes might be achieved by GSK-3β signalina pathway.
Animals ; Cornus ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Glycogen Synthase Kinase 3 ; Glycogen Synthase Kinase 3 beta ; Glycosides ; Heat-Shock Proteins ; Mitochondria, Heart ; physiology ; Myocardial Infarction ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Polysaccharides ; Protective Agents ; pharmacology ; therapeutic use ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Transcription Factors
3.Effect of treadmill training on the locomotor function in a rat model of dorsal root ganglion resection
Pu-Tian AN ; Wen-Wen ZHU ; Mai-Chao LI ; Xiao-Juan CUI ; Yan ZHOU ; Yi-Meng ZHANG ; Li-Xin JIN
Chinese Journal of Tissue Engineering Research 2018;22(16):2537-2541
BACKGROUND: Peripheral nerve injury can lead to extensive changes in central nervous system, and exercise training can promote the recovery of locomotor function following central nervous system injury. OBJECTIVE: To observe the changes of locomotor function and the expression levels of vesicular glutamate transporter VGLUT1 in the spinal cord in a rat model of dorsal root ganglion resection after treadmill exercise and to explore the effect of treadmill training on the locomotor function after peripheral nerve injury. METHODS: Thirty-nine 10-week-old male Wistar rats were randomized into experimental (n=15), control (n=15) and sham operation (n=9) groups. The rats in the experimental and control groups received the dorsal root ganglion resection at L3and L4segments to establish the model of peripheral nerve injury under local anesthesia, while the rats in the sham operation group were only subjected to dorsal root ganglion exposure. The rats in the experimental group underwent 15 m/minute treadmill training at postoperative 7 days, while rats in the other two groups were in free movement. Gait analysis was performed at preoperative 3 days, postoperative 7, 14, 21, and 28 days, respectively, and the behavioral changes of rats were observed. The tissue sections were obtained from L3segment at postoperative 7, 14, and 28 days to detect the expression levels of VGLUT1 in the spinal cord by immunohistochemistry. RESULTS AND CONCLUSION: The peroneal nerve function index in the experimental and control groups was lower than that before surgery and that in the sham operation group at postoperative different time points (all P < 0.05). The index in the experimental and control groups was the lowest on day 7 postoperatively (P < 0.05), then the index gradually increased, but was still lower than the preoperative level (P < 0.05). The index in the experimental group was significantly higher than that in the control group at postoperative 21 and 28 days (P < 0.05). The expression levels of VGLUT1 in the lamina IX in the experimental and control groups were significantly lower than those in the sham operation group at different time points after surgery (P < 0.01). The levels in the experimental group were significantly higher than those in the control group at postoperative 14 and 28 days (P < 0.05). The levels in both groups on a decline after surgery, especially the control group (P < 0.05). These results suggest that treadmill can promote the recovery of locomotor function post peripheral nerve injury.
4.Status of vaccination against hepatitis B among postgraduate students in medical higher education institutions in Guangzhou.
Chao-shuang LIN ; Jian-yun ZHU ; Li MAI ; Wen-Hui LEE ; Zhi-liang GAO
Chinese Journal of Experimental and Clinical Virology 2007;21(2):114-116
OBJECTIVETo investigate the status of vaccination against hepatitis B among postgraduate students of medical institutions of higher education in Guangzhou.
METHODSHBsAg and anti-HBs in the serum samples from 1139 postgraduate students were detected by ELISA. Data on hepatitis B vaccine inoculation were investigated by using a questionnaire. Statistical analyses were performed by using SAS software.
RESULTSThe HBsAg positive rate among the 1139 postgraduate students was 2.90 percent. The HBsAg positive rates in hepatitis B vaccine inoculated (1.15 percent) and non- inoculated (21.69 percent) postgraduate students were significantly different (x2=119.11, P<0.0001). The positive rates of HBsAb between the two groups were also significantly different (x2=62.05, P<0.0001). Among the hepatitis B vaccine inoculated students, 17.31 percent were negative for HBsAb. The positive rate of HBsAb among those inoculated the vaccine within the past 3 years was higher than that among those inoculated the vaccine earlier (0-3 years vs. 4-6 year, P=0.0089) (0-3 years vs. 7-9 years, P=0.0172) (0-3 years vs. >9 years, P=0.0474). The positive rate of HBsAb among the students who received hepatitis B vaccine booster dose was higher than that of the students who did not receive any booster dose (P=0.0093).
CONCLUSIONWith the increase of ages, the effect of vaccination for hepatitis B decreased. Male populations may be more susceptible to hepatitis B virus than female. It is necessary to monitor HBsAb levels for those who were inoculated with HBV vaccine more than 3 years ago to give booster dose in time to prevent HBV infection.
Adult ; China ; Female ; Hepatitis B ; immunology ; prevention & control ; virology ; Hepatitis B Antibodies ; blood ; Hepatitis B Vaccines ; administration & dosage ; immunology ; Hepatitis B virus ; immunology ; Humans ; Male ; Middle Aged ; Students, Medical ; Surveys and Questionnaires ; Vaccination ; Young Adult
5.Diagnosis of drowning by detecting gyrB and 16S rRNA genes of Aeromonas hydrophila using PCR-capillary electrophoresis.
Bai-Sheng MAI ; Qu-Yi XU ; Chao LIU ; Jian ZHAO ; Ya-Li HAN
Journal of Southern Medical University 2016;36(11):1550-1554
OBJECTIVETo establish a method for diagnosis of freshwater drowning by amplifying gyrB and 16S rRNA genes of Aeromonas hydrophila using PCR coupled with capillary electrophoresis (CE).
METHODSDNA samples were extracted from human, 18 planktons (including Candida albicans, Aeromonas hydrophila, and 16 species of algae), and 30 cases of tissue samples (including the lung, liver, and kidney, all examined with microwave digestion-vacuum filtration-automated scanning electron microscopy) from human cadavers, including 28 freshwater drowning victims and 2 with natural death. The DNA samples were amplified with the primer AH (for gyrB gene) and primer Ah (for 16S rRNA gene), and the products were analyzed with CE.
RESULTSPCR amplification followed by CE yielded negative results for DNA of human, Candida albicans and 16 species of algae, whereas a positive result was found for Aeromonas hydrophila DNA with PCR products of 195 bp (with primer AH) and 350 bp (with primer Ah). In the 28 drowning cases, the detection rates of Aeromonas hydrophila using primer AH were 96.4% in the lung tissue, 71.4% in the liver tissue, and 60.7% in the kidney, as compared with the rates of 75.0%, 42.9%, and 32.1% using primer Ah, respectively. The positive rates for Aeromonas hydrophila in the organs of the drowning victims were 82.1% and 53.6% with primer AH and primer Ah, respectively. The detection showed negative results in the 2 cases of natural deaths. The two primers produced significantly different detection rates of Aeromonas hydrophila (P<0.05).
CONCLUSIONPCR coupled with CE for detecting gyrB gene of Aeromonas hydrophila has a high sensitivity in assisting a diagnosis of freshwater drowning. Detection of both the gyrB gene and 16S rRNA gene of Aeromonas hydrophila can yield more convincing evidence of the diagnosis of freshwater drowning.
6.Diagnostic efficiency and result of prostate biopsy for patients with t-PSA between 4.0 and 10 ng/ml
Jian-Nan LIU ; Hai-Xing MAI ; Nan QU ; Xue-Chao LI ; Ya-Lin WANG ; Chen HUANG ; Li-Jun CHEN
Military Medical Sciences 2017;41(10):825-829
Objective To investigate the diagnostic efficiency and result of prostate biopsy for patients with t -PSA between 4.0 and 10 ng/ml.Methods This analysis was based on 20 qualified research papers from such lectronic databases as PubMed, MEDLINE, EMBASE and Cochrane from January 2010 until September 2017.Data extracted was analyzed using classic Meta-analysis with R software .The random or fixed effect model analysis was used to estimate the rate.Heterogeneity was analyzed using I 2 statistic.Results Totally 5481 patients were included in the 20 research papers. The positive rate of prostate biopsy was 20.6%, with t-PSA between 4.0 and 10 ng/ml, which was higher than the rate in the data from CUA Guide(2014).The difference was statistically significant .Conclusion Patients should be subjected to prostate biopsy if their t-PSA ranges 4.0 from 10 ng/ml regardless of the rate of f/t-PSA.The Gleason grade is relatively low when PSA is in the gray area , and the risk is also low.
7.Changes of adrenomedullin 2/intermedin in the lung of rats with chronic hypoxic pulmonary hypertension.
Xiao-fang FAN ; Ping HUANG ; Yong-sheng GONG ; Xiao-mai WU ; Liang-gang HU ; Li-xian TIAN ; Chao-shu TANG ; Yong-zheng PANG
Chinese Journal of Applied Physiology 2007;23(4):467-471
AIMTo investigate the changes and probable roles of adrenomedullin2/intermedin (AIDM2/IMD), a novel micromolecular bioactive peptide, in the lungs of rats with chronic hypoxic pulmonary hypertension.
METHODSTwenty male SD rats were randomly divided into normal control group (NC) and normobaric hypoxia group (4H). The protein levels of ADM and ADM2/IMD) in the plasma and lung were measured by radioimmunoassay and immunohistochemistry. The mRNA expressions of ADM, ADM2/IMD and their receptors C (RLR, RAMP1, RAMP2 and RAMP3 in the lung tissue were determined by reverse transcription-polymerase chain reaction (RT-PCR).
RESULTS(1) The rat model of chronic pulmonary hypertension was confirmed by the increased mean pulmonary arterial pressure (mPAP) and weight ratio of right ventricle to left ventricle plus septum [RV/(LV + S)] in 4H group compared to NC group. (2) The concentrations of ADM in the plasma and lung homogenate of 4H group were 2.3 and 3.2 folds of NC group, respectively (all P < 0.01). The levels of ADM2/IMD were higher 89.6% and 45.0% in the plasma and lung homogenate of 4H group than those of NC group (respectively, P < 0.01, P < 0.05). (3) The mRNA expressions of ADM2/IMD and ADM in the lung of 4H group were up-regulated (respectively, P < 0.01, P < 0.05 vs. NC group). The expressions of CRLR and RAMP1 mRNAs were down-regulated (all P < 0.01 vs. NC group), while the levels of RAMP2 and RAMP3 mRNAs were no significant difference between the two groups. (4) The strong ADM2/IMD immunostaining was detected in the endothelial and adventitial cells of the rat pulmonary arteriole.
CONCLUSIONADM2/IMD, like its paralog ADM, might be closely related to the chronic hypoxic pulmonary hypertension in rats. The disorders of the gene expression and/or the synthesis and metabolism of ADM2/IMD and its receptor CRLR/RAMP1 possibly take part in the pathogenesis of chronic hypoxic pulmonary hypertension in rats.
Adrenomedullin ; metabolism ; Animals ; Hypertension, Pulmonary ; etiology ; metabolism ; Hypoxia ; complications ; metabolism ; Lung ; metabolism ; Male ; Neuropeptides ; metabolism ; Rats ; Rats, Sprague-Dawley
8.Intrauterine growth curves for body weight, body length, head circumference, chest circumference, and crown-rump length in 16 887 neonates with a gestational age of 27-42 weeks in Shenzhen, China.
Xiao-Yun HUANG ; Hui-Long LIU ; Min LEI ; Hui-Fen MAI ; Chao-Hui LIAN ; You-Cong LI
Chinese Journal of Contemporary Pediatrics 2017;19(8):877-886
OBJECTIVETo establish the intrauterine growth curves of neonates in Shenzhen, China and to investigate the intrauterine growth of neonates in Shenzhen.
METHODSCross-sectional cluster sampling was performed for an on-the-spot investigation of 16 887 neonates (9 418 males and 7 469 females) with a gestational age of 27-42 weeks who were born in two hospitals in Shenzhen from April 2013 to September 2015. The Lambda Mu Sigma (LMS) method was used for the curve fitting of body weight, body length, head circumference, chest circumference, and crown-rump length.
RESULTSThe 3rd-97th percentile intrauterine growth curves for body weight, body length, head circumference, chest circumference, and crown-rump length were plotted for the neonates with a gestational age of 27-42 weeks who were divided into three groups (male, female, and mixed). The male neonates had significantly higher curves for the five indices than the female counterparts. The pattern and changing trend of body weight curves of these neonates were basically consistent with those in China Neonatal Network.
CONCLUSIONSThe percentile intrauterine growth curves for body weight, body length, head circumference, chest circumference, and crown-rump length in neonates with a gestational age of 27-42 weeks in Shenzhen which has been established can provide a reference for clinical practice in the department of neonatology.
Body Height ; Body Weight ; Cross-Sectional Studies ; Crown-Rump Length ; Female ; Fetal Development ; physiology ; Gestational Age ; Head ; anatomy & histology ; Humans ; Infant, Newborn ; Male ; Thorax ; anatomy & histology
9.A real-time qPCR method to identify diatom UPA gene for the drowning diagnosis
Xiangdong LIU ; Chao LIU ; Quyi XU ; Fan PENG ; Sunlin HU ; Baishen MAI ; Hong LIU ; Yue LI ; Huiying HU ; Jichao XU ; Shurui ZHANG ; Yali HAN ; Zhujun TAN
Chinese Journal of Forensic Medicine 2018;33(2):124-129
Objective To establish a Real-time quantitative PCR method (qPCR) for the detection of diatom UPA barcoding genes and evaluate its application in the drowning diagnosis. Methods The homologous sequences of diatoms UPA gene was obtained by Blast from GeneBank, based on which the universal primers for diatoms were designed. DNA were extracted from 2 common human symbiotic bacteria (Escherichia coli, Bifidobacterium longum), 3 species of planktonic bacteria, 15 species of planktonic algae, tissue samples (lung, liver and kidney) from human cadavers (28 drowning victims, 1 victims by non-drowning in the water, 3 victims deaths on land) in 32 cases. The specificity, sensitivity and repeatability of the designed primers were tested. The positive rates of diatoms detection in the drowning cases were calculated. The results of the real-time quantitative method were evaluated comparatively by Microwave Digestion-Vacuum Filtration-Automated Scanning Electron Microscopy (MD-VF-Auto SEM) and PCR-Capillary Electrophoresis (PCR-CE). Results The results showed that the primers UPA99 had strong specificity for the diatomaceae (Synedra radians, Navicula sp., Melosira varians, Cyclotella sp. and Nitzschia sp.) DNA. The melting curve of the amplified product was smooth; the peak was narrow; the melting temperature was (87±1)℃. The sensitivity of qPCR method was 1.56×10-5ng/μL with the detection range of 1.56×102ng/mL~1.56×10-5ng/μL, in contrast with the PCR-CE method (1.56×10-3ng/μL). This real-time PCR method showed high repeatability and stability with the coefficient of variation less than 2%. The detection rate of lung, liver and kidney was 89.3%, 71.4% and 64.3% respectively. Conclusion The established qPCR method, based on the universal primers designed for diatom UPA gene, has high specificity, high sensitivity and good repeatability. With a promising prospect for application, qPCR is suitable for drowning diagnosis.
10.Pretreatment Serum Amyloid A and C-reactive Protein Comparing with Epstein-Barr Virus DNA as Prognostic Indicators in Patients with Nasopharyngeal Carcinoma: A Prospective Study.
Qiu Yan CHEN ; Qing Nan TANG ; Lin Quan TANG ; Wen Hui CHEN ; Shan Shan GUO ; Li Ting LIU ; Chao Feng LI ; Yang LI ; Yu Jing LIANG ; Xue Song SUN ; Ling GUO ; Hao Yuan MO ; Rui SUN ; Dong Hua LUO ; Yu Ying FAN ; Yan HE ; Ming Yuan CHEN ; Ka Jia CAO ; Chao Nan QIAN ; Xiang GUO ; Hai Qiang MAI
Cancer Research and Treatment 2018;50(3):701-711
PURPOSE: The measuring Epstein-Barr virus (EBV) DNA is an important predictor of nasopharyngeal carcinoma (NPC). This study evaluated the predictive value of pretreatment serum amyloid A (SAA) and C-reactive protein (CRP) comparing with EBV DNA in patients with NPC. MATERIALS AND METHODS: In an observational study of 419 non-metastatic NPC patients, we prospectively evaluated the prognostic effects of pretreatment SAA, CRP, and EBV DNA on survival. The primary end-point was progress-free survival (PFS). RESULTS: The median level of SAA and CRP was 4.28 mg/L and 1.88 mg/L, respectively. For the high-SAA group (> 4.28 mg/L) versus the low-SAA (≤ 4.28 mg/L) group and the high-CRP group (> 1.88 mg/L) versus the low-CRP (≤ 1.88 mg/L) group, the 5-year PFS was 64.5% versus 73.1% (p=0.013) and 65.2% versus 73.3% (p=0.064), respectively. EBV DNA detection showed a superior predictive result, the 5-year PFS in the EBV DNA ≥ 1,500 copies/mL group was obviously different than the EBV DNA < 1,500 copies/mL group (62.2% versus 77.8%, p < 0.001). Multifactorial Cox regression analysis confirmed that in the PFS, the independent prognostic factors were including EBV DNA (hazard ratio [HR], 1.788; p=0.009), tumour stage (HR, 1.903; p=0.021), and node stage (HR, 1.498; p=0.049), but the SAA and CRP were not included in the independent prognostic factors. CONCLUSION: The results of SAA and CRP had a certain relationship with the prognosis of NPC, and the prognosis of patients with high level of SAA and CRP were poor. However, the predictive ability of SAA and CRP was lower than that of EBV DNA.
C-Reactive Protein*
;
DNA*
;
Herpesvirus 4, Human*
;
Humans
;
Observational Study
;
Prognosis
;
Prospective Studies*
;
Serum Amyloid A Protein*
;
Survival Analysis