Effect of minimally invasive drilling closed drainage on the expression of HIF-1α, Claudin-5, TGF-β and Smad2/3 in patients with chronic subdural hematoma / 中国医师杂志

Objective To investigate the effects of single-hole and double-hole drilling and closed drainage on the expression of Hypoxia inducible factor-1α (HIF-1α),Claudin-5,transforming growth factor-β (TGF-β) and Smad2/3 in the epidermis of patients with chronic subdural hematoma.Methods 100 patients with chronic subdural hematoma were randomly divided into single hole and double hole drainage group according to random number table.Immunohistochemical streptavidin-peroxidase (SP) was used to detect the expression of TGF-β protein,and Western blot was used to detect the expression of HIF-1α,Claudin-5 and Smad2/3 in the epihematoma of the two groups before and after operation.Results Compared with pre-operation,the expression of HIF-1 α,TGF-β and Smad2/3 protein in adventitia of hematoma in both groups decreased after operation,especially in the double-hole group (P ＜ 0.05).The expression of Claudin-5 protein in adventitia of hematoma was significantly increased in both groups,especially in the double-hole group,with statistically significant difference (P ＜ 0.05).Conclusions Single-hole and double-hole drilling and sealing drainage is an effective method to treat chronic subdural hematoma.It can reduce the expression of HIF-1α,TGF-β and Smad2/3 protein in the epidermis of hematoma,and significantly increase the expression of Claudin-5,and the effect of double-hole drilling and sealing drainage is more significant.

Prevention and control of oral diseases via "Common Risk Factor Approach" / 中华口腔医学杂志

People are generally more aware of infectious diseases, cardiovascular diseases, trauma and other fatal diseases rather than oral diseases. In fact, the oral disease as a whole is ranked the third among the chronic diseases of human beings. There have been accumulating evidences that oral health plays a significant role in general health and quality of life. There is a wide recognition that oral health shares common risky/pathogenic factors with other Non-Communicable Diseases (NCD). Oral microorganisms may cause dental caries and periodontal diseases, and they may also cause atherosclerosis and heart diseases, thus these usually end up to chronic diseases. On the other hand, unhealthy diet, physical inactivity, tobacco and alcohol consumption, psychological stress, poor sanitation, accidents and a sedentary lifestyle contribute to both oral diseases and a number of general chronic diseases. Oral health cannot be dealt with in isolation from other health issues. That is why the WHO recommended the "Common Risk Factor Approach (CRFA)" for oral health promotion. In this article, the authors give essential interpretation of CRFA and make suggestions on preventing and controlling oral diseases via CRFA.

Effect of minimally invasive drilling closed drainage on the expression of HIF-1α, Claudin-5, TGF- β and Smad2/3 in patients with chronic subdural hematoma / 中国医师杂志

Objective@#To investigate the effects of single-hole and double-hole drilling and closed drainage on the expression of Hypoxia inducible factor-1α (HIF-1α), Claudin-5, transforming growth factor-β (TGF-β) and Smad2/3 in the epidermis of patients with chronic subdural hematoma.@*Methods@#100 patients with chronic subdural hematoma were randomly divided into single hole and double hole drainage group according to random number table. Immunohistochemical streptavidin-peroxidase (SP) was used to detect the expression of TGF- β protein, and Western blot was used to detect the expression of HIF-1α, Claudin-5 and Smad2/3 in the epihematoma of the two groups before and after operation.@*Results@#Compared with pre-operation, the expression of HIF-1α, TGF-β and Smad2/3 protein in adventitia of hematoma in both groups decreased after operation, especially in the double-hole group (P<0.05). The expression of Claudin-5 protein in adventitia of hematoma was significantly increased in both groups, especially in the double-hole group, with statistically significant difference (P<0.05).@*Conclusions@#Single-hole and double-hole drilling and sealing drainage is an effective method to treat chronic subdural hematoma. It can reduce the expression of HIF-1α, TGF-β and Smad2/3 protein in the epidermis of hematoma, and significantly increase the expression of Claudin-5, and the effect of double-hole drilling and sealing drainage is more significant.

Focus on the recent state policy for oral health in China / 中华口腔医学杂志

President Xi presented an important address in the National Health and Wellness Conference and the high strategic priority for promoting people's health in China was emphasized. Thereafter, a number of documents of state policy on health and wellness were issued successively. These documents covered important contents on oral health, which had great significance as a milestone. This article reviewed the documentation process and analyzed the key points on oral health. The release of these series of government documents had provided policy support for integrating oral health into significant health policies, building the first barrier for oral health, preventing and treating oral diseases based on strategies for common risk factors, adopting strategies to combine both the whole population and high-risk groups, and developing health-centered oral massive health industry, etc.

How to write and publish a scientific article in stomatology / 中华口腔医学杂志

The general principles and key points in writing of a scientific article in stomatology were interpreted based on the national guideline and the author's personal experiences in the present article. Efforts should be made by the authors focusing on core information, refinement and description of their papers. In the second half of the article, the general process of paper review was introduced. The article also gave suggestions on how to response to the reviewers' questions. It is well recognized that a good scientific journal was created by good authors, good reviewers and good editors. The author proposed that efforts by above mentioned three parties should be gathered to make more valuable, delicately designed and well performed clinical research articles be published.

The influence of Rosenthal effect on the psychological status of pregnant women at risk of miscarriage in early pregnancy / 中国实用护理杂志

Objective To explore the influence of Rosenthal effect on the psychological status of pregnant women at risk of miscarriage in early pregnancy. Methods From January 2014 to June 2015 151 cases of early pregnancy abortion risk women were set as the control group, and was given conventional psychological intervention.From July 2015 to December 2016 135 cases of early pregnancy abortion risk women were named as the observation group by convenient sampling selection, which was given interventionbased on Rosenthal effect on the basis of routine psychological intervention. The Self-rating Depression Scale (SDS) and the Self-rating Anxiety Scale (SAS) score, the introversion and extroversion scores and the satisfaction degree with intervention were compared between the two groups before and after the intervention. Results There was no significant difference in SDS and SAS scores, inotropic challenge and extroversion challenge between the two groups before treatment (P >0.05). The scores of SDS and SAS, the inotropic challenge and extroversion challenge scores were 41.45 ± 4.26, 40.34 ± 5.82,4.76 ± 1.03,5.55 ± 1.26 in the observation group after intervention,and 47.22 ± 3.93,47.18 ± 7.04,5.39 ± 1.12, 6.43 ± 1.86 respectively in the control group. There were significant difference in scores of SDS and SAS, the inotropic challenge and extroversion challenge (t=2.215-2.573, P <0.05). The satisfaction rates of the observation group and the control group were 93.32%(126/135)and 74.17% (112/151) respectively, the difference was statistically significant (χ2=5.921, P<0.05). Conclusions The intervention based on Rosenthal effect on the basis of conventional psychological intervention for early pregnancy abortion risk women can relieve negative emotions such as anxiety and depression, besides it can also improve satisfaction degree of inpatients with intervention.

Efficacy and safety of levetiracetam for adult seizure: a randomized controlled trial / 第二军医大学学报

Objective To evaluate the efficacy and safety of levetiracetam (LTA) for adult seizure (AS).Methods A randomized,double-blinded,double-dummy,positive drug controlled trial was conducted.One hundred and twenty eligible AS patients were randomly divided into two groups:intervention group and control group,with 60 in each group.Patients in the intervention group received LTA tablet plus valproate sodium mimetic tablet,and patients in the control group received valproate sodium tablet and LTA mimetic tablet.The treatment course was 26 weeks in both groups,and the patients was followed up for 3 months after the treatment.The outcomes included total efficacy rate,weekly epilepsy seizure frequency,seizure duration,quality of life (measured by QOLIE-31 Scale) and adverse events related to drugs after 1-3 days of treatment and at 3 months of follow-up.Results The weekly epilepsy seizure frequency,seizure duration and QOLIE-31 score were not significantly different between the two groups before treatment.The total efficacy rates after treatment and at 3 months of follow-up in the intervention group were 95.0％ (57/60) and 91.7％ (55/60),respectively,and were significantly higher than those in the control group of 71.7％ (43/60) and 63.3％ (38/60) (P＜0.01).The weekly epilepsy seizure frequency,seizure duration and QOLIE-31 score after treatment and at 3 months of follow-up were significantly different as compared with before treatment in both groups (P＜0.01);and there were significantly different between the two groups (P＜0.01).The adverse events after treatment were similar between both groups.Conclusion The efficacy of LAT is superior to the valproate sodium tablet for AS,with the less toxicity,and it can be clinical drug of choice for AS.

Effect of root canal sealers on biocompatibility of human periodontal ligament cells / 北京大学学报(医学版)

Objective:To compare the effects of three root canal sealers with respect to time on biocom-patibility of human periodontal ligament cells (hPDLCs).The sealers included zinc oxide and eugenol based sealers (ZOE),epoxy resin sealers (ERS)and silicone based sealers (SBS).Methods:hPDLCs were primarily cultured,with the method combining of tissue explant and enzymatic digestion.The cells were then exposed to different extract fluids:(1)ZOE extracted for 24 h group ;(2)ZOE extracted for 1 week group;(3)ZOE extracted for 2 weeks group;(4)ERS extracted after 24 h group;(5)ERS extracted after 1 week group;(6)ERS extracted after 2 weeks group;(7)SBS extracted after 24 h group;(8)SBS extracted after 1 week group;(9)SBS extracted after 2 weeks group;(10)Dulbecco modified Eagle’s me-dium/F12(DMEM/F12)as negative control group.Cell morphology was observed under an inverted mi-croscope.Cell proliferation was measured by methyl-thiazol-diphenyltetrazolium (MTT)assay.ALP assay kit was used for measuring alkaline phosphatase (ALP)activity.Sealers of 2 weeks’setting time were then immersed in an osteogenic medium for examination of mineral nodules and calcium deposits.Re-sults:Considering the relative growth rate (RGR),ZOE was severely to moderately cytotoxic (RGR:13.6% -39.9%),while ERS was slightly or not cytotoxic (RGR:87.6% -95.3%).Only SBS did not show any cytotoxicity after setting (RGR:91.8% -106.7%).The setting time influenced the cytotoxic-ity of ERS which decreased after 1 week.Considering the ALP activity,there was no difference between SBS group and control group(F =3.397,P =0.053).According to the results of calcium deposits, ZOE:D562 nm =0.180 ±0.050,ERS:D562 nm =2.968 ±0.201,SBS:D562 nm =3.623 ±0.039,Control:D562 nm =3.477 ±0.102,the ranking of ALP activity and calcium deposits was as follows:ZOE

In vitro study of biological characteristics of new retrograde filling materials iRoot / 北京大学学报(医学版)

Objective:To study the biological characteristics of new retrograde filling materials iRoot BP plus and iRoot FS.Methods:(1 )The roots were cut into 3 mm in length,and the root canals were pre-pared to 1 mm in diameter,followed by being filled with iRoot BP plus,iRoot FS,or mineral trioxide ag-gregate (MTA).The specimens were immersed in simulated body fluid (SBF).The ability of minerali-zation in vitro was detected through three studies.First,the mineralization of specimens was analyzed through scanning electron microscope observations and energy dispersive X-ray spectrometer.Then,the pH of SBF was monitored using pH meter.(2)The extracts were gained by immersing blocks of iRoot BP plus,iRoot FS,and MTA (8 mm diameter and 2 mm height)into dulbecco’s modified eagle medium (DMEM).The effects of the extracts on proliferation of MG63 cells were detected through MTT assay. The gene expression level of alkaline phosphatase (ALP)was analyzed by quantitative real-time PCR, and the expression of ALP activity was observed by ALP activity staining.Results:(1 )The formation of minerals could be observed on the surfaces of iRoot BP plus,iRoot FS,and MTA at the end of 24 h,and there were more amounts of apatite aggregated after 14 days.The values of Ca/P ratios of apatites were 1.43,1.39,and 1.51,respectively.(2)The pH of SBF could be raised to 8.09 ±0.07,7.91 ± 0.06,and 8.1 1 ±0.06,respectively,significantly higher than the blank.(3)The extracts of iRoot BP plus,iRoot FS,and MTA of dilutions of 1∶5 and 1∶10 presented no effect of proliferation of MG63 cells. (4)iRoot BP plus and iRoot FS could significantly up-regulated the levels of ALP messenger RNA ex-pression,while there was no obvious difference in ALP staining among the iRoot BP plus,iRoot FS, MTA,and the blank.Conclusion:The present study shows that iRoot has displayed good mineralization capability in vitro and capability to promote differentiation and mineralization of MG63 cells,inferring that iRoot may have good bioactivity.

Antibacterial effect of self-etching adhesive systems on Streptococcus mutans / 北京大学学报(医学版)

Objective:To investigate the antibacterial effect of different self-etching adhesive systems against Streptococcus mutans (S.mutans).Methods:Six reagents ClearfilTM SE Bond primer (SP), ClearfilTM SE Bond adhesive (SA),ClearfilTM Protect Bond primer (PP),which contained antibacterial monomer methacryloyloxydodecylpyridinium bromide (MDPB),ClearfilTM Protect Bond adhesive (PA), positive control chlorhexidine acetate [CHX,1% (mass fraction )],and negative control phosphate buffer solution (PBS)were selected.They were mixed with S.mutans for 30 s respectively,then colony-forming units (CFU)were counted after incubated for 48 h on brain heart infusion (BHI)agar medium. The 6 reagents were applied to the sterile paper discs,and distributed onto the BHI agar medium with S. mutans and incubated for 24 h,then the inhibition zones were observed.CHX,PBS,PP,and SP were added on the dentin with artificial caries induced by S.mutans and kept for 30 s,then confocal laser scanning microscope (CLSM)was used to observe the live and dead bacteria after staining.The ratio of live to dead bacteria was calculated.PP+PA and SP+SA were applied on the dentin according to the manual and light cured.S.mutans were incubated on the samples for 2 h,ultrasonically treated and in-cubated on BHI agar medium for 48 h,then CFU was counted.The data were analyzed by non-parametric analysis and one-way ANOVA.Results:Compared with PBS,the PP,SP,PA,SA and CHX showed the antibacterial effect on free S.mutans (P<0.05 );SP and PP showed stronger antibacterial effect than PA,SA and CHX (P<0.05).CHX,SP and PP presented inhibition zones,while PBS,SA and PA did not.Compared with PBS,the CHX,SP and PP could lower the ratio of the live to dead bacteria significantly (P<0.05).Cured self-etching adhesive systems did not show any antibacterial effect on the free S.mutans.Conclusion:The primer of self-etching adhesives ClearfilTM SE Bond and ClearfilTM Pro-tect Bond showed significant antibacterial effect on free and attached S.mutans.The adhesive only showed antibacterial effect on free S.mutans before light-cured polymerization.After being cured,the self-etching adhesive systems did not show antibacterial effect anymore.

Comparison of periapical radiography and cone-beam computed tomography in en-dodontic treated teeth for assessment of periapical lesions / 北京大学学报(医学版)

Objective:To compare the assessments of the presence or absence and the changes of post-treatment periapical lesions using periapical radiographs versus cone-beam computed tomography (CBCT).Methods:Imaging records were selected from a sample of 233 radiographic examinations (in-cluding periapical radiographs and CBCT)of patients with chronic apical periododontitis who received treatment and review in Department of Cariology and Endodontology of Peking University School of Stoma-tology.After testing the inter-observer and intra-observer agreement,two observers determined the pre-sence or absence of a periapical lesion and classified the changes of lesions in 4 categories:absence,re-duction or enlargement of lesion,or uncertain.The differences between CBCT and periapical radiographs in detecting the presence or absence and the changes of periapical lesions were compared using McNemar test and Fisher’s exact test respectively.Results:In the study,233 teeth were assessed with both periapi-cal radiographs and CBCT images.Periapical lesions were detected in 178 teeth on CBCT scans and in 146 teeth on periapical radiographs.CBCT images revealed a significantly larger number of lesions than were revealed by periapical radiographs (P <0.01 ).There was disagreement on the changes of lesions between the two radiological technologies in 25% teeth,and the difference was statistically significant (P <0.01 ). Conclusion:Significant differences were observed between periapical radiographs and CBCT in detection of post-treatment periapical lesions and assessment of the changes of periapical lesions.

Adhesive performance of infiltrating resin bonded on dentin in vitro / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the adhesive interface and micro-tensile bond strength (μTBS) of infiltrating resin directly bonded to normal dentin.</p><p><b>METHODS</b>Twenty extracted human molars were collected and ground to expose fresh dentin surface. An infiltrating resin (ICON, DMG, Germany) was served as experimental group and Clearfil SE Bond adhesive (Kuraray, Japan) as control group. Following the application of primer (Kuraray, Japan), the specimens were applied infiltrating resin or adhesive respectively and blocks of composite resin were built up. The adhesive interfaces were observed using scanning electron microscope (SEM) and the μTBS was measured by micro-tensile test before and after thermal cycling.</p><p><b>RESULTS</b>The infiltrating resin could penetrate into micro-structure of dentin created by SE Bond primer. A layer of about 180 μm-long and dense resin tags was observed under SEM in infiltrating resin group. The μTBSs were (35 ± 10) MPa before and (35 ± 9) MPa after thermal cycling respectively in infiltrating resin group, and the difference was not statistically significant (P>0.05). The μTBSs were (38±8) MPa before and (24±7) MPa after thermal cycling respectively in control group, and the difference was statistically significant (P<0.05). After thermal cycling, the μTBS of infiltrating resin group was significant higher than that of control group.</p><p><b>CONCLUSIONS</b>The infiltrating resin could penetrate into the micro-structure of dentin created by SE Bond primer. The bond strength and the bonding durability of infiltrating resin were similar to that of SE Bond adhesive.</p>

Micro-CT observations of the adaptation at gingival wall in ClassⅡrestorations with different dental restorative materials / 北京大学学报(医学版)

Objective: To evaluate the adaptation of different materials for gingival layer in Class Ⅱrestorations using Micro-CT.Methods:Eighteen extracted human premolars were selected, and ClassⅡcavities were prepared.The teeth were randomly divided into six groups and restored using layering tech-nique.Six materials were used for gingival layer, including four injectable materials:Beautifil Flow Plus F00 (F00), Beautifil Flow F10 (F10), Filtek Z350 Flowable (Z350F), FujiⅡLC CAPSULE (Fuji), and two packable materials: BeautifilⅡ (BF), Filtek Z350 (Z350).The restored teeth were scanned with micro-CT and the images were 3D reconstructed to evaluate the volumes and the distribution of the voids on the restoration-tooth interface of the gingival layer.The volume of the voids were statistically analyzed using nonparametric Jonckheere-Terpstra tests.Results: The volumes ( mm3 ) of the voids on the restoration-tooth interface were: Z350F (0.000 15), F10 (0.000 39), F00 (0.012), Fuji (0.070), Z350 (0.16) and BF (0.20).There were significant differences between Z350F/F10 and Fuji/Z350/BF (P<0.05).Most of the voids were found on the point-line angles of the cavities.Con-clusion:The voids on the restoration-tooth interface were mainly on the point-line angles of the cavities. Injectable materials with high flowablility could reduce the restoration-tooth interface voids significantly when used for the gingival layer in ClassⅡrestorations.

Real temperature of the continuous-wave pluggers / 北京大学学报(医学版)

Objective:To measure the real temperatures on the pluggers of three continuous-wave de-vices, and to provide theoretical reference to evaluate thermal damage and heat ’s influence on the filling materials.Methods:The dual channel K type thermocouple was contacted to various sizes ’ pluggers in three different continuous-wave devices (BeeFill, Elements, B&L), and the highest temperatures at dif-ferent points ( tip, and 2 mm, 5 mm, 10 mm from the tip) of the pluggers ( preset temperature was 200℃) were recorded.The measurements were performed 5 times.T-test was used to compare the real tem-peratures at the tips with that set on the display and one-way ANOVA was used to compare the tempera-tures of the pluggers in different devices , sizes and points .Results:The highest temperature was at the tip of BeeFill 40/0.03 plugger (198.7 ±7.7) ℃, but there was on statistical differences between that and the preset temperature 200℃.The temperatures of the remaining pluggers were obviously lower than 200 ℃(P<0.05).The lowest temperature of the pluggers was detected at 10 mm from the tip of BeeFill 60/0.06 plugger (69.9 ±4.0) ℃.The highest temperature of each plugger was detected at the tip or 2 mm from the tip (112.1 to 198.7℃,and the median was 140.8℃).Conclusion:The real temperature of most continuous-wave pluggers included in this study is below the set temperature 200 ℃.

Comparison of the incidences of apical root cracks after canal preparation with two nickel-titanium rotary systems:an in vitro study / 北京大学学报(医学版)

Objective: To compare the incidences of root cracks after canal instrumentation with HyFlex CM system and the ProTaper Universal system .Methods:Sixty mandibular incisors were mounted in resin blocks with simulated periodontal ligaments , and the apex was exposed .The control group of 20 teeth was not prepared , and the other 40 teeth were divided into 2 experimental groups ( n=20 ) .The 40 root canals of the experimental groups were instrumented using HyFlex CM and ProTaper Universal to the major apical foramen ( AF).The horizontal sections 1 mm, 2 mm, and 3 mm from the apex were observed under an optical stereomicroscope at 25 ×magnification .The presence of cracks was noted . Results:No cracks were found in the control teeth .Cracks were found in 1 of 20 ( 5%) teeth in HyFlex CM group , and 17 of 20 ( 85%) teeth in ProTaper Universal group .The difference between the two experimental groups was statistically significant (P<0.01).Conclusion: The HyFlex CM files caused fewer root cracks than the ProTaper Universal files during the root canal instrumentation .

Synergistic effects of lysozyme with EDTA-2Na on antibacterial activity / 北京大学学报(医学版)

Objective:To evaluate the synergistic antibacterial effects of lysozyme with ethylenediami-netetraacetic acid disodium salt (EDTA-2Na) on Enterococcus faecalis (E.faecalis) and Porphyromonas endodontalis ( P.endodontalis) .Methods:E.faecalis and P.endodontalis were cultured and adjusted to 108 CFU/mL.Then 0.3, 0.5, 1, 2, 5, 10, 50, 100, 150 and 300 g/L of lysozyme were prepared with deionized water;and the lysozyme solutions were mixed with 0.5, 1.0, 2.0 g/L of EDTA-2Na, re-spectively.The bacteria and lysosome with/without EDTA-2Na interacted for 15 min, then water-soluble tetrazolium (WST) working solution was added and the activity of the bacteria was calculated by mea-suring optical densities at 450 nm and 630 nm with microplate spectrophotometer .Results:Regarding the pure lysozyme from 0.5 g/L to 150 g/L, more E.faecalis and P.endodontalis were inhibited when the concentration of lysozyme was higher , especially for E.faecalis.There was synergistic effect of lysozyme with EDTA-2Na on antibacterial activity , which was related to the concentration of lysozyme .On E.fae-calis, the antibacterial activity of lysozyme with EDTA-2Na was 1.2-3.7 folds than the pure lysozyme when the concentration of lysozyme was 0.5-50 g/L (P0.05). Conclusion: For E.faecalis and P.endodontalis, a low concentration of lysozyme with EDTA-2Na showed significant synergistic antibacterial activity , while a high concentration of lysozyme with EDTA-2 Na did not .

Effect of resin infiltration treatment on the colour of white spot lesions / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This study aimed to evaluate the effect of resin infiltration and fluoride solution on masking different demineralized white spot lesions by assessing color change.</p><p><b>METHODS</b>Artificial white spot lesions were produced on 60 human molars. Each sample had at least two enamel surfaces opened (named A and B). The samples were randomly divided into groups 1, 2, and 3 according to their time of demineralization (24, 48, and 72 h). After demineralization, the A spot of each sample was treated by resin infiltration. The B spot was treated with 0.1% fluoride solution daily for 30 days. After the remineralization of the B spot, resin infiltration was used again on the B spot of each sample. Color assessment was performed by a spectrophotometer in five distinct stages: baseline, after the production of artificial caries, after resin infiltration of A spots, after 30 days of fluoride solution treatment of B spots, and after resin infiltration of remineralized B spots.</p><p><b>RESULTS</b>Before demineralization, the L* values of spots A and B in all groups were not significantly different (P > 0.05), whereas the L* values of spots A and B were significantly increased after demineralization. The L* values of A spots recovered significantly after treatment by resin infiltration (P<0.05), but only groups 1 and 2 reached the baseline. The L* values of B spots had no significant differences (P > 0.05) after fluoride treatment compared with that after demineralization. After resin infiltration on B spots, the L* values recovered but could not reach the baseline nor the level of A spots treated by resin infiltration only.</p><p><b>CONCLUSION</b>Resin infiltration is a more effective treatment for masking white spot lesions than traditional fluoride treatment. The effect of masking white spot lesions has certain relationships with the degree of demineralization and activity of the lesion.</p>

Biological effect of inhibition of Notch signaling pathway on human dental pulp cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of Notch signaling pathway on human dental pulp cells.</p><p><b>METHODS</b>The γ-secretase inhibitor N-[N-(3, 5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester(DAPT) was applied to inhibit the Notch signaling pathway of human dental pulp cells. The solvent dimethly sulfoxide (DMSO) served as the negative control.Senescence conditions were evaluated by cells morphology changes, the alkaline phosphatase (ALP) expression and its activity, senescence-associated β-galactosidase (SA-β-Gal) expression and the senescence related gene p53 expression.</p><p><b>RESULTS</b>After inhibition of the Notch signaling pathway, morphology changes, including flatter cells, larger plasma area, were seen in the 10th passage human dental pulp cells. ALP expression and activity showed a significant decrease at the 8th passage after inhibition (35.36 ± 2.55) U/g, compared with the negative control group[(49.76 ± 4.30) U/g] (t = 4.989, P = 0.008).SA-β-Gal-positive cells could be seen as early as the 8th passage and more positive cells were evident at the 10th passage. The relative expression level of p53 gene was elevated in the 10th passage cells (1.7 ± 0.4) compared with the negative control group(1.0) (t = 3.581, P = 0.012).</p><p><b>CONCLUSIONS</b>Human dental pulp cells became senescent at earlier passages after inhibition of Notch signaling pathway.Notch signaling pathway may affect life cycle of human dental pulp cells.</p>

In vitro effects of hyperbaric oxygen and DDP on proliferation of lung adenocarcinoma cell line A549/DDP / 中华胸心血管外科杂志

Objective To evaluate the effects of hyperbaric oxygen (HBO) and cisplatin (DDP) on inhibition of A549/DDP cells in vitro and to explore the impacts of HBO on cell cycle and apoptosis.Methods The cytotoxicity of HBO and DDP was determined by Methyl thiazolyl tetrazolium (MTF) assay; flow cytometry (FCM) was used to investigate the impacts on cell cycle and apoptosis of cell line A549/DDP.Results Hyperbaric oxygen alone significantly suppressed A549/DDP cells proliferation (P ＜ 0.05),compared with control group of normal oxygen,and the inhibition ratio was 2.90％.DDP at concentrations ranging from 3 μg/ml to 24 μg/ml significantly inhibited the proliferation of A549/DDP cells in a dose dependent manner,that was concentrations of 3,6,12 and 24 μg/ml brought inhibition ratio of 1.87％,4.62％,11.15％ and 30.45％ ; Hyperbaric oxygen can enhance the inhibition effect of DDP to A549/DDP cells,when hyperbaric oxygen affiliated with DDP of concentrations above,the inhibition ratios were 4.37％,8.92％,21.88％ and 48.71％,respectively,which has significant difference with the single DDP groups.FCM analyses showed that HBO arrested A549/DDP cells at the S phase,that was cell number of G0/G1 phase reduced significantly and of S phase raised significantly,compared with normal oxygen group(P ＜0.01),that was the percentages of cells in S phase of control group were 9.5％ and HBO group were 20.9％,while the percentages of cells in G0/G1phasc were 82.2％ and 66.3％,respectively.In addition,there were more apoptotic cells in the HBO group with the percentage of 7.9％,while the percentage was 2.8％ in the normal oxygen group.Conclusion Hyperbaric oxygen could play together with DDP to inhibit A549/DDP cells proliferation.HBO could block the cell cycle at S period and induce apoptosis.

A research on bond strength and interface of dentin adhesives / 实用口腔医学杂志

Objective: To evaluate bond strength and interface of various dentin adhesives by a modified interface processing method. Methods:Nine extracted human molars were ground to expose fresh dentin surface. Three dentin adhesives (Single Bond, Clearfil SE Bond and Clearfil S3 Bond) were applied respectively and a block of composite resin was built up. The specimens were then stored in distilled water for 24 h at 37 ℃ and sectioned into beams of 0.9 mm×0.9 mm cross-sectional area. The microtensile bond strength was determined with Microtensile Tester(n=15). In addition, the bonding specimens were conditioned with 6 mol/L HCl, 5% NaOCl and 0.08 mg/ml hyaluronidase to observe the adhesive interfaces by SEM. Results: Significant differences in bond strength were observed among the three adhesives(P<0.05): SE Bond (45.06±5.29) MPa> Single Bond (35.50±6.40) MPa> S3 Bond (30.46±3.82) MPa. Single Bond showed resin tags about 9-12 μm long and gaps between hybrid and adhesive layers. No obvious boundary between hybrid layer and adhesive were observed for both SE Bond and S3 Bond, while the length of resin tags were 9-14 μm and 4-7 μm for SE Bond and S3 Bond respectively. Conclusion:The morphology of the bond interface of dentin adhesive has a relationship with the bond strength.