BACKGROUND: Tooth intrusion easily leads to root resorption. Previous studies regarding orthodontic treatment-caused tooth root resorption or retrospective clinical studies based on X-ray films have great errors in outcome evaluation because of intrusion force which cannot be precisely controlled. OBJECTIVE: This study established dog models of mini-implant anchorage for incisor intrusion to observe the histological changes of tooth root and periodontal tissue and to evaluate the feasibility and safety of mini-implant anchorage for incisor intrusion. METHODS: Nine dogs were assigned to one control group (n = 1) and four experimental groups per time to sacrifice (1, 2, 4 and 12 weeks; n = 2 dogs for each experimental group). No force was added to the control group. In the experimental groups, mini-implant as an anchorage was placed in the buccal alveoli between maxillary second and third incisors on each side. A traction force of 100 g was imposed to each side to intrude the maxillary first and second incisors on each side. At 1, 2, 3, and 4 weeks (traction force was imposed for 4 weeks and after withdrawal of extraction force, mini-implant was retained in place for 8 weeks), dogs were sacrificed. The first and second incisors together with gingival and alveolar bone were completely resected to prepare histological specimens. Following hematoxylin-eosin staining, histological changes of tooth root and periodontal tissue were observed. RESULTS AND CONCLUSION: Compared with the control group, in the 1-week group, histological changes were primarily at the root tip and alveolar ridge crest, alveolar bone and cementum were absorbed and peridental membrane presented glassy degeneration in local region; in the 2-week group, bone resorption degree and range were obviously enlarged, and bone resorption developed from root tip, root middle part to cervical part; in the 4-week group, bone resorption was still active and the glassy degeneration of peridental membrane disappeared; in the 12-week group, significant improvement in alveolar bone and cemental surface was observed, bone lacuna had deposition of newly formed bone, and peridental membrane was orderly arranged. These findings reveal that in the mini-implant anchorage for dog incisor intrusion, early histological changes primarily appear in the root tip and alveolar ridge crest, presenting as alveolar bone and cemental resorption and the glassy degeneration of the peridental membrane. Bone resorption extent and range expand with the persistence of traction force. After withdrawal of traction force, tooth root and periodontal tissue were gradually repaired

A highly sensitive electrochemical deoxyribonucleic acid(DNA) biosensor based on multi-walled carbon nanotubes(MWNT)/Ag-TiO_2 composite film was developed. The solution containing Ag-TiO_2-MWNT composite was casted on the carbon paste electrode surface to form a robust film, which combine the advantages of the good biocompatibility of Ag-TiO_2 naocomposite and the fine conductivity, as well as the large active surface area of carbon nanotubes. The composite could greatly improve the immobilization capacity of the probe DNA. The morphologies and electrochemistry of the nanocomposite film were investigated by scanning electron microscopy and electrochemical techniques including electrochemical impedance spectroscopy and cyclic voltammetry, respectively. DNA hybridization events were monitored by a label-free method of electrochemical impedance spectroscopy. This label-free electrochemical impedance DNA biosensor showed high sensitivity and selectivity for phosphinothricin acetyltransferase gene sequence assay. The multicomponents films also displayed a high stability during repeated regeneration and hybridization process.

The effects of SB203580 (SB) with different concentrations at different time points on renal function, apoptosis, P38MAPK activity and the expression, as well as the P38MAPK substrates in renal ischemia/reperfusion injury were investigated. Forty-nine rats were divided into 7 groups at random (n = 7 in each group) according to the durations of ischemia/reperfusion injury and the time of medication. Based on the orthogonal Latin side, the rats were injected, by caudal vein, with the same volume but different dosages of SB. BUN and Scr were determined. The apoptosis was detected with TUNEL kit. The protein was assayed qualitatively and semi-quantitatively by Western blot. The results showed that SB could significantly reduce the increased Scr and BUN, the apoptosis of renal tubular epithelia and the activation of P38MAPK all caused by renal ischemia/ reperfusion injury in a dose-dependent manner (P < 0.05). And the effect was most predominant when SB was given 3 h before renal ischemia. This suggested that SB could significantly alleviate renal ischemia/reperfusion injury. Administration of SB 3 h before ischemia at the concentration of 5 micromol/L could obtain an optimal effect.
Apoptosis/*drug effects ; Enzyme Inhibitors/pharmacology ; Imidazoles/*pharmacology ; Kidney/*blood supply ; Kidney/pathology ; Pyridines/*pharmacology ; Random Allocation ; Rats, Sprague-Dawley ; Reperfusion Injury/enzymology ; Reperfusion Injury/*pathology ; p38 Mitogen-Activated Protein Kinases/*metabolism

[Objective] The aim was to choose the best feeder layer by observing the effects of various human feeders supporting human embryonic stem cells (hESCs), and to probe the correlation between the levels of basic fibroblast growth factor (bFGF) secreted by feeders and the growth of the hESCs. [Methods] The primary cells from various tissues were cultured, including foreskin, stromal endometrium, villus, adult fallopian tubal, fetal skin, fetal muscle and mouse embryonic fibroblasts (MEFs). The hESCs were transferred to various feeders, and then the best condition was probed, which was based on the feeder density and the time of mitomycin-C acting on the feeder. Comparing the characteristics of the hESCs, the best feeder was chosen of all kinds of feeders from various tissues that support the hESCs. The level of bFGF secreted by various feeders was detected using ELISA. [Results] All of tested feeders could support the hESCs growth for over 10 passages in the culture, especially the foreskin and the adult fallopian tubal. The density of feeders was related with the morphology and the differentiation rate of the hESCs. According to the characteristics of feeder, the feeder ranking was as follows: foreskin, stromal endometrium, villus, adult fallopian tubal, fetal skin and fetal muscle. Based on the characteristics of the hESCs, the order of feeders was: foreskin, adult fallopian tubal, stromal endometrium, villus, fetal muscle and fetal skin. The levels of bFGF (pg·10~(-5)·mL~(-1)) secreted by various feeders were as follows: adult fallopian tubal (13.23±3.39), foreskin (1.99±0.17), villus (1.40±0.17), fetal muscle (2.02 ±1.59), stromal endometrium (0.38±0.28), and fetal skin (0.29±0.29). [Conclusion] The foreskin and the adult fallopian tubal could support the hESCs better than others though all of them could;do, especially the, foreskin. The bFGF that secreted by the adult fallopian tubal was the highest of all. The correlation was not obvious .between the levels of bFGF secreted by feeders and the growth of the hESCs.

Objective To study the effect of attachment, coping style and social support on mental health in technical school students.Methods 372 technical school students were assessed by ECR(Experiences in Close Relationship's Inventory) ,Symptom Check Scale List-90 (SCL-90) and Coping Style Scale For Secondary School Students( CSS), Adolescent Self-Rating Life Events Checklist ( ASLEC), Perceived Social Support Scale (PSSS).Results ( 1 ) Life events had significant correlations with all indexes score of attachment anxiety ( r =0.293 ～ 0.356, P ＜0.01 ) ,the scale of coping style focus on emotion and the total score of SCL-90 ( r = 0.259 ～0.509, P＜0.01 ) ,and the total score of perceived social support had significant correlations with the total score of SCL-90 ( r =-0.238, P ＜ 0.01 ).( 2 ) Structural equation analysis ( model fit: χ2 = 540.593, RMSEA = 0.114,NFI = 0.864 ,CFI =0.884, P ＜ 0.01 ) showed that life events affect on mental health through the mediation effects of coping style focus on emotion, attachment anxiety and the perceived social support and coping style focus on emotion had most mediating effect on mental health ( mediation effect = 33.2% ).Conclusion Life events had both direct effect and indirect effect through coping style focus on emotion, attachment anxiety and the Perceived Social Support on mental health.

Objective To study the association of vitamin D receptor(VDR) gene BsmI polymorphism and the genetic susceptibility of vitamin D deficiency rickets in infants and to explore a new way of diagnosis and treat-ment. Methods Case-control study was adopted. 56 infants confirmed with rickets (case group) and 76 cases of normal infants (control group) were chosen as the subjects. PCR-RFLP was applied to examine VDR gene BsmI site polymorphism. The frequencies of the VDR genotype and allele were compared between the two groups. Results Frequencies of BB,Bb and bb genotypes were 3.6% (2/56),21.4% (12/56) and 75.0% (42/56) in the rickets group,and 1.3% (1/76),18.4% (14/76) and 80.3% (61/76) in the control group respectively(χ20.521,P> 0.05),frequencies of B,b alleles were 14.3% (16/112),85.7% (96/112) in the rickets group and 10.5% (16/152),89.5% (134/152) in the control group respectively(χ20.783,P>0.05). Multiple logistic regression analysis showed that VDR gene polymorphism Bsml had not higher risk of vitamin D deficiency rickets in Infants. Conclusion VDR gene polymorphism BsmI doesn't appear to pose risk on infants in developing vitamin D deficien-cy rickets.

Objective To investigate the effects of obesity on blood pressure variation and plasma levels of nitric oxide (NO) and endothelin (ET) in elderly hypertensive patients.Methods A total of 175 elderly patients with hypertension were screened for this study.Based on body mass index,they were categorized into three groups with normal weight (n =69),overweight (n=56) and obesity (n=50).24 hour dynamic blood pressure,NO and ET levels were monitored.Results No significant differences in 24 h systolic blood pressure,daytime systolic blood pressure,nighttime systolic blood pressure,24 hours diastolic blood pressure (24 h-DBP) and night time diastolic blood pressure were found among the groups (all P＞0.05).Morning systolic and diastolic blood pressure were higher in obese group than in normal weight and overweight groups(both P＜0.05).The daytime diastolic blood pressure was higher in obese group than in overweight group.24 h systolic blood pressure variation,daytime systolic blood pressure variation,and blood pressure pattern were higher in obese group than in overweight and normal weight group [(12.6 ± 2.7)％ vs.(10.4 ±2.2)％ and (9.4±1.9)％,(12.2±2.9)％ vs.(10.2±2.2)％ and (9.2±2.1)％,(5.2±10.5)％vs.(1.4± 6.9) ％ and (1.8 ± 8.2) ％ group,all P＜ 0.05].The nighttime systolic blood pressure variation,24 h diastolic blood pressure variation,daytime diastolic blood pressure variation were increased in obese group as compared with normal weight group [(9.8 ± 3.7)％ vs.(8.2 ± 3.1)％,(15.3±3.3)％ vs.(13.2±4.2)％,(14.7±3.7)％ vs.(12.9±3.8)％,all P＜0.05].No differences were found in nighttime diastolic blood pressure variation among the groups.Plasma NO level was lower in obese group than in overweight and normal weight group [(29.8± 14.2)μmol/L vs.(47.9± 18.6) μmol/L and (94.6 ± 42.9) μmol/L,P＜0.01].Plasma ET level was significantly higher in obese group than in overweight group and normal weight group [(46.5± 9.8)ng/L vs.(37.3±4.8) ng/L and (31.1± 5.5) ng/L,P＜0.01].24 h systolic blood pressure variation was significantly correlated with plasma NO level (r =0.340,P =0.004) in normal weight group.Conclusions Obesity can effectively increase blood pressure variation and ET level,and reduce plasma NO level in elderly hypertensive patients.Obesity is one of the most important influencing factors for blood pressure variation,plasma NO and ET levels.

Objective To detect the value of circulating tumor cells(CTCs)in peripheral venous blood in patients with metastatic breast cancer. Methods 50 female patients with advanced advanced metastatic breast can-cer hospitalized in our hospital from May 2016 to December 2016 were enrolled in the research. Patients were divid-ed into oligometastases group and extensive metastasis group through multi-department comprehensive analysis andimaging diagnosis. 10 cases with early stage breast cancer were selected randomly. 10 healthy female volunteers were recruited as control group. After obtaining written informed consent from research subjects ,7.5 mL peripheral blood was drew from patients and volunteers prior to starting a new line of chemotherapy ,surgery or other treat-ment. CTCs counts from Blood samples were detected density gradient centrifugation associate with flow cytometry. Results The base line was formulated as CTCs≥5/7.5 mL positive and CTCs<5/7.5 mL negative. By comparing the positive expression of CTCs in early and advanced metastatic breast cancer(Pa = 0.01,P < 0.05),positive CTCs was associated with advanced metastatic breast cancer. Comparision of the positive expression of CTCs between oligometastases group and the extensive transfer group showed significant difference in the CTCs count be-tween the two groups(Pb = 0.018,P < 0.05). In the corresponding period,no positive CTCs was detected in all healthy volunteers. Conclusion CTCs count was associated with metastatic breast cancer. There was a correlation between tumor metastasis and CTCs count (the more widely metastasis ,the higher the detection rate of CTCs). CTCs may be of relevant value in the diagnosis and treatment ,and prognosis evaluation of metastatic breast cancer.

Objective To investigate the effect induced by specific inducible nitric oxide synthase (iNOS) inhibitor 1 400 W on nasopharyngeal carcinoma CNE-2 cells lines and its mechanism.Methods CNE-2 cells were treated by different concentrations of 1 400 W,diamminedichloroplatinum (DDP),and both chemicals.Cell counting kit-8 (CCK-8) was used to examine the viability of cells.Quantitative realtime polymerase chain reaction (qRT-PCR) was applied to detect the iNOS mRNA expression.Results The expression of iNOS mRNA was down-regulated by 1400W and was positively correlated with inhibitionrate of cell proliferation.1 400 W inhibits proliferation of CNE-2 cell in a concentration-dependent manner.The proliferation inhibition rate of CNE-2 cells treated by 1 400 W combined with DDP was not enhanced.Conclusions Specific inducible nitric oxide synthase inhibitor 1 400 W can exerts anti-tumor effect though inhibiting the expression of iNOS mRNA;The mechanism of chemosensitization induced by iNOS inhibitor on CNE-2 cells may be closely related level of down-regulation of iNOS expression.

Objective To obtain shRNA sequences that can stably block the expression of Nuclear Factor kappa- B (p65) in the prostate cancer cell line LNCaP and construct the lentivirus vector.And validate the gene function of p65 in the cell line. Methods According to p65 genetic information, we design siRNA1, siRNA2, siRNA3 those three siRNA sequences targeting the ods area of p65 gene and then form the corresponding four pairs of complementary single strand DNA of shRNA, including the sense strand and the antisense strand. The synthetic shRNA sequence was inserted into the empty pSIH1-H1-copGFP shRNA Vector, and after transfecting the prostate cancer cells , the inhibitory effect of p65 mRNA by different sequences was detected through real-time PCR, and the inhibitory effect of p65 protein expression was detected by Western-blotting. Thus we can obtain highly effective shRNA sequences in the inhibition of p65 in prostate cancer cells. MTT, flow cytometry, transwell were chosen to test the cell growth, migration and invasive power in vitro to compare the difference of the experimental group, control group and negative group. Results The third shRNA sequence had the best inhibitory effect and the inhibitory effect of p65 mRNA in prostate cancer cell line was 59 % and the protein was 81%. It's position locates in p65 (NM_021975 ) 1096-1113 and it's stemloop sequence is 5'-GATCCGCCCTATCCCTTTACGTCATTCAAGAGATGACGTAAAGGGATAGGGCTTTTTG-3'. After transfecting, the prostate cancer cell line had the low expression of p65 stably. Through MTT, we got the growth curve, which showed that the growth ability of experimental group was significantly decreased compared with the control group and the Logarithmic growth didn't appear in the first 96 hours. Flow cytometry test displayed that the percentage of G0-G1-phase cells in experimental group was 61.49%, and the control group was 44.89%, idle group was 41.52%, which was increasing oberviously. The S-phase cells in the experimental group was 28.58%, compared with the 47.36% and 46. 10% diminished. The results of transwell showed that the experimental group had 16. 5000±6. 62076 cells and the other two groups had 45. 6333 13. 54159 and 36. 8333±5. 68412 cells, which showed the invasive power of experimental group was significantly declined(P＜0.05).Conclusions It's successful to obtain shRNA sequences that can stably block the expression of p65 in the prostate cancer cell line LNCaP and construct the lentivirus vector. p65 can positively regulates the biological behavior of prostate cancer LNCaP cell line in the cell growth, migration and invasive power.