Objective:To establish an in vitro root canal model infected by Enterococcus faecalis and to observe the morphology, distribution and relative position of Enterococcus faecalis in infected root canals.Methods: Ten human healthy premolars extracted for orthodontic reasons were collected. Following sterilization , a total of 5 specimens were aseptically transferred to separate Eppendorf tubes containing 1. 5 mL brain-heart infusion broth (BHI) inoculated with 0.1 mL Enterococcus faecalis suspension that had been adjusted to Mcfarland 5, and were incubated at 37℃ for 21 days. The other 5 specimens were as controls. The roots of all specimens were then split into two halves along the mesiodistal axis. One half was processed with light microscopic ( Brown & Brenn stain) to check the bacteria in dentinal tubules, and the other was observed with SEM to investigate the bacterial status in infected root canals. Results: Enterococcus faecalis could penetrate into the dentinal tubules about 330-1 000μm. A dense bacterial aggregation composed of Enterococcus faecalis and amorphous matrix was observed in the apical third of the root canals, whereas Enterococcus faecalis were seen free-floating or planktonic in the crown and middle third of the root canals . No microorganisms were found in the root canals of the controls. Conclusion:Enterococcus faecalis could form bacterial biofilm on the root canal walls and penetrate into the dentinal tubules. The in vitro model designed was simple, and had good practicability to make a further comparative evaluation of various antimicrobial methods in the reduction of intracanal bacteria.

Objective:To establish an in vitro root canal model infected by Enterococcus faecalis and to observe the morphology,distribution and relative position of Enterococcus faecalis in infected root canals.Methods: Ten human healthy premolars extracted for orthodontic reasons were collected.Following sterilization,a total of 5 specimens were aseptically transferred to separate Eppendorf tubes containing 1.5 mL brain-heart infusion broth(BHI) inoculated with 0.1 mL Enterococcus faecalis suspension that had been adjusted to Mcfarland 5,and were incubated at 37 ℃ for 21 days.The other 5 specimens were as controls.The roots of all specimens were then split into two halves along the mesiodistal axis.One half was processed with light microscopic(Brown & Brenn stain) to check the bacteria in dentinal tubules,and the other was observed with SEM to investigate the bacterial status in infected root canals.Results: Enterococcus faecalis could penetrate into the dentinal tubules about 330-1 000 ?m.A dense bacterial aggregation composed of Enterococcus faecalis and amorphous matrix was observed in the apical third of the root canals,whereas Enterococcus faecalis were seen free-floating or planktonic in the crown and middle third of the root canals.No microorganisms were found in the root canals of the controls.Conclusion: Enterococcus faecalis could form bacterial biofilm on the root canal walls and penetrate into the dentinal tubules.The in vitro model designed was simple,and had good practicability to make a further comparative evaluation of various antimicrobial methods in the reduction of intracanal bacteria.

OBJECTIVE:To study the anti-oxidative effects of spirulina kinase (SPK) in vitro. METHODS:The methods of phenanthroine-Fe2+ oxidation method,DPPH and auto-oxidation of pyrogallol were used to measure the effects of different concen-trations of SPK on scavenging hydroxyl (OH-) free radical,DPPH free radical and superoxide anion (O2-) free radical;IC50 of SPK was calculated. Prussian blue reaction was used to determine total reducing ability(by absorbance)of different concentrations of SPK to Fe3+. Vitamin C(VC)was used as positive control in above trials. RESULTS:SPK could eliminate the OH-free radical, DPPH free radical and O2- free radical in concentration-dependant manner,and the maximum elimination rate of SPK to OH- free radical and DPPH free radical were 86.82% and 78.98%(IC50 were 54.31,0.636 g/L),which were higher than VC (64.77%, 73.49%). The maximum elimination rate of SPK to O2- free radical was 78.31%(IC50 was 3.918 g/L),which was lower than VC (94.14%). In reducing ability test,SPK improved absorbance in reducing ability test system,and maximum absorbance was simi-lar to VC in concentration-dependant manner. CONCLUSIONS:SPK has obvious anti-oxidant activities in vitro.

Objective To elucidate the effects of SP600125 at different concentrations on the proliferation and osteo-differentiation of human adipose-derived stem cells (hASCs).Methods The hASCs harvested were cocuhured with SP600125 at concentrations of 0 μmol/L,1 μmol/L,5 μmol/L and 10 μmol/L in growth medium (OM group) and in osteogenesis medium (OM group),respectively.The DNA quantitative assay was carried out to evaluate proliferation of the hASCs;flow cytometry was used to determine the effect of SP600125 on the cell cycles of hASCs;Alkaline phosphatase level (ALP) and calcium deposition tests were conducted to observe the effects of SP600125 at different concentrations on osteogenic differentiation of the hASCs.Results The proliferation of hASCs was inhibited by 42.1％ when the cells were cocultured with SP600125 at the concentration of 10 μmol/L;the suppression decreased with decreased concentration of SP600125.The hASCs of phase G0/G1 in GM cocultured with SP600125 at the concentration of 10 μmol/L were more than those in GM cocultured with dimethylsulfoxide at the same concentration.ALP test revealed that after 10 days of culture in vitro the staining was more and more weakened and scattered and the ALP activity was more and more decreased with the increased concentration of SP600125.The extracellular calcium deposition of hASCs after 14 days of culture in vitro showed that the size and number of calcium nodules decreased with the increased concentration of SP600125.Conclusion SP600125 can suppress the proliferation and osteogenic differentiation of hASCs in vitro.

This investigation was made with special reference to the effect of the combined use of nuclear factor-kappaB (NF-kappaB) inhibitor Pyrrolidine dithiocarbamate(PDTC) and Paclitaxel on the expression of Matrix metalloproteinases (MMP-9) and its inhibitor TIMP-1, and on the proliferation and invasion of human breast cancer cell line MCF-7. The MCF-7 cells were treated with PDTC and Paclitaxel. The effect on proliferation was evaluated by MTT assay. The cell cycle was analyzed by flow cytometry. Western blot was used to determine the change of NF-kappaB p65, MMP-9 and TIMP-1 expression in MCF-7 cells after treatment. RT-PCR was used to detect NF-kappaB p65 mRNA expression. The invasion ability of MCF-7 cells was tested by the invasion, migration and cell adhesion assay. The cell growth was significantly slowed down and the cell cycle was arrested at G0/G1 phase after the combined treatment. The expression of NF-kappaB p65 and MMP-9 was down-regulated and the invasion ability of MCF-7 cells was decreased after the combined treatment. In conclusion,PDTC combined with paclitaxel effectively inhibited cell proliferation, induced cell cycle arrest, and decreased cell invasion ability of breast cancer MCF-7 cells. The mechanism may be associated with the inhibiting effect of PDTC on the NF-kappaB-related gene expression.
Antineoplastic Agents, Phytogenic ; pharmacology ; Breast Neoplasms ; pathology ; Cell Line, Tumor ; drug effects ; Cell Proliferation ; drug effects ; Drug Synergism ; Female ; Humans ; NF-kappa B ; antagonists & inhibitors ; Neoplasm Invasiveness ; Paclitaxel ; pharmacology ; Pyrrolidines ; pharmacology ; Thiocarbamates ; pharmacology

As an important human body sound signal, heart sound is of great value in the researches on diagnostics of heart diseases. This study sought to explore the methods of transmitting heart sound through the telephone correspondence system for simultaneous telemetering cardiac contractility and heart rate. Heart sounds were transmitted from a phone to another phone with 4 modes, the wirelessly transmitted distance between the two phones being 5 m, 10 km, and 1000 km, respectively. The results of experiments show that telemetering cardiac contractility and heart rate can be realized by the telephone correspondence system. Such methods have the advantages of being noninvasive, inexpensive, rapid and convenient; moreover, they can be used repeatedly and be available for in-home use.
Heart Sounds ; physiology ; Humans ; Phonocardiography ; instrumentation ; methods ; Signal Processing, Computer-Assisted ; instrumentation ; Telemedicine ; methods ; Telemetry ; methods

OBJECTIVE: To explore the genetic and clinical characteristics of near-tetraploidy/tetraploidy karyotype (NT/T) in patients with myelodysplastic syndrome (MDS). METHODS: Cytogenetic findings of 1576 inpatients with primary MDS were retrospective analyzed, among which 9 were diagnosed with NT/T. Clinical data including gender, age, morphology, genetic feature and prognosis were analyzed. RESULTS: The prevalence of MDS patients with NT/T (NT/T-MDS) among all cases was 0.57%. Karyotyping analysis suggested that eight MDS patients had sole NT/T, while the remainder one had a complex karyotype. In addition to the typical morphology of MDS, NT/T-MDS had unique morphology including huge blast, double-nuclear cell and irregular nuclear membrane. One NT/T-MDS patient gave up therapy, and the remaining eight underwent the first course of treatment, albeit with poor prognosis. Only one patient had complete remission, one had partial remission, three had no remission; and three had converted to acute myeloid leukemia. CONCLUSION NT/T-MDS is rare and has unique morphology. Generally, NT/T-MDS patients have poor prognosis. However, NT/T cannot be simply classified as high-risk group, but with consideration whether they have affected particular chromosomal structures as well as other clinical data.
Humans ; Karyotype ; Leukemia, Myeloid, Acute/complications* ; Myelodysplastic Syndromes/pathology* ; Prognosis ; Retrospective Studies ; Tetraploidy

Objective To investigate the expressions of miR-21 in clinical lung tissues,serum of lung cancer patients and X-ray irradiated A549 cells in vitro and in vivo.Methods A549 cells were irradiated with 2 and 4 Gy X-rays,and pulmonary metastasis model of lung cancer in nude mice was established to detect the expression of miR-21 in vitro and in vivo,as well as in clinical lung tissues of different pathological types serum sample of lung cancer patients and NSCLC patients whether or not received radiotherapy.The survival rate was further analyzed in the above mention NSCLC patients.Results The miR-21 expressions was up-regulated in 60.0％ of tissue samples of NSCLC patients,and it was up-regulated in 50.5％ serum samples of lung cancer patients (52 out of 103).The miR-21 expressions in lung adenocarcinoma and squamous cell carcinoma had significant difference (x2 =5.766,P ＜ 0.05).In the serum samples of 87 NSCLC patients,miR-21 was detected in 66.7％ samples from the patients of radiotherapy but only 39.6％ of patients without radiotherapy (x2 =6.321,P ＜ 0.05).Kaplan-Meier curves showed that the survival rate of patients with low miR-21 expression was higher than that with high miR-21 expression (P ＜ 0.05).Multivariate Cox regression analysis demonstrated that the miR-21 expression,regional lymph node metastasis and radiotherapy were independent prognostic factors for NSCLC patients.The expression of miR-21 was up-regulated significantly in X-ray irradiated A549 cells at different time-points after irradiation (t =-7.552--1.206,P ＜ 0.05).Furthermore,the expression of miR-21was up-regulated in the serum and lung of nude mice (t =-47.845--2.356,P ＜ 0.05).Conclusions The X-ray irradiation could up-regulate the expression of miR-21 in A549 cells in vitro and in vivo,which might be correlated with the enhanced metastasis of A549 cells.

Objective: To investigate the effect of different mechanisms of liver-protection drugs in clinic and compare which one is best for the proliferation of irradiated HL-7702, laying the basis of liver-protection drugs choose in clinic on theory and practice. Methods: Human liver parenchyma cells HL-7702 were given single 6 MV X ray irradiation at a dose of 10Gy, the cells’ morphology were detected under an inverted microscope at 24h, 48h and 72h. Then, MTT was used to assess the survival rate of the cells to evaluate the effect of the X ray. The representive medicines which mechanism may relate to RILD were chosen and diluted into various concentrations with culture medium according to clinical and relative reports. Different concentrations of medicines were used to protect the cells damaged by the X ray. Comparing the effect with MTT and measure SOD, MDA for the best one. Further research on its protection of oxidative damage. T-test, F test and non- paramiter test were used for statistical analysis. Results: 2.5 mg/ml and 1 mg/ml of magnesium isoglycyrrhizinate both have an effect on the proliferation of liver cells, especially the concentration of 1 mg/ml. The injection of polyene phosphatidyl choline show trivial effect at the concentrations of 250 μmol/L and reduced glutathione(GSH) did not demonstrate relative functions. Further research on the magnesium isoglycyrrhizinate, found its protection at 48h to oxidative damage (P < 0.05), but the effect is weak at 24h and 48h. Conclusions In three kinds of representing medicines, magnesium isoglycyrrhizinate has preferable effects on liver parenchyma cells and show a bright future in the treatment of RILD.

Objective: To investigate the effect of over-expression of paired related homoeobox 1 (PRRX1) on apoptosis of hepatocellular carcinoma SMMC7721 cells, and to explore its detailed mechanism. Methods： ：Lentivirus-mediated PRRX1 over-expression vector (pGMLV-PRRX1) and empty vector (Vector) were respectively infected into SMMC7721 cells, and the mRNA and protein expression levels of PRRX1 in infected cells were detected by qPCR and WB. The effect of PRRX1 over-expression on the cell proliferation and apoptosis of SMMC7721 cells were assessed by CCK-8 assay and Annexin-V FITC/PI double staining flow cytometry assay, respectively. The change of mitochondrial membrane potential of SMMC7721 cells was detected by mitochondrial membrane potential assay kit (JC-10 staining assay). The enzymatic activities of caspase-8 and caspase-9 in infected cells were detected by using caspase activity assay kit (spectrophotometric method). The protein expression levels of p53, Bcl-2, Bax, Fas, Cleaved-caspase-3 and Cty C expressed in mitochondria and cytosol were evaluated by WB. Results： ：PRRX1 over-expressed SMMC7721 cell line was successfully constructed, and the protein and mRNA expression levels of PRRX1 were significantly increased in lentivirus infected cells (all P< 0.01). Compared with control group and vector group, over-expression of PRRX1 significantly inhibited cell proliferation, weakened mitochondrial membrane potential, but increased the rate of apoptosis, elevated the shear level of caspase-3, promoted the release of Cyt C protein from mitochondrial into cytosol and increased the enzymatic activity of caspase-9 (all P<0.05 or P<0.01). In addition, over-expression of PRRX1 also promoted the protein expressions of p53 and Bax but inhibited the protein expression of Bcl-2 (all P< 0.05 or P<0.01); however,it had no significant effect on the expression of Fas protein and the enzymatic activity of caspase-8 (all P＞ 0.05). Conclusion： ：Over-expression of PRRX1 induces apoptosis in hepatocellular carcinoma SMMC7721 cells, which may be related to the activation of p53-mediated mitochondrial apoptotic pathway