Trace heavy metals and harmful elements in roots and rhizomes of herbs: Screening level analysis and health risk assessment / 中草药·英文版

Objective: Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines (CHMs), and roots and rhizomes parts showed a higher content than other parts. To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes, 720 batches of the sample representing 20 species of herbs from different sources were collected. Methods: The content of Pb, Cd, As, Hg, and Cu in the digests was determined using ICP-MS. The chronic hazard index estimate based on non-cancer hazard quotient (HQ) was applied for potential health risk assessment of Pb, Cd, As, Hg, and Cu via consumption of CHMs. Results: Compared with the Chinese limit standard (Chinese Pharmacopoeia Commission, 2020 edition) of Pb, Cd, As, Hg, and Cu in Ginseng Radix et Rhizoma, the exceedance percentage of Pb in total samples was 14.1%, which were generally far higher than Cd, As, Hg, and Cu. Health risk assessment results based on hazard quotient calculating showed that total HQ of Cu, Pb, As, Cd, and Hg in Pulsatillae Radix and Clematidis Radix et Rhizoma exceeded 1, with the value of 1.543 and 1.235. Besides, Arsenic had the highest HQ value (0.957) in Pulsatillae Radix. Conclusion: Consuming raw materials of Pulsatillae Radix and Clematidis Radix et Rhizoma may pose a potential risk and Arsenic residues in Pulsatillae Radix deserved special attention.

Clinicopathological characteristics and risk factors on hepatocellular carcinoma differentiation / 公共卫生与预防医学

Objective To investigate the clinicopathological characteristics and independent risk factors of hepatocellular carcinoma (HCC) differentiation.  Methods A total of 108 HCC patients who underwent operation and treatment were reviewed and classified into low differentiation group (n= 29, 26.85%), medium differentiation group (n=53, 49.07%) and high differentiation group (n=26, 24.07%) according to pathological diagnosis. The clinicopathological characteristics and the expression levels of Ki67 and P53 in each group were compared and analyzed. Logistic regression model was used to analyze the risk factors for low differentiation of HCC.  Results The proportion of cirrhosis, the positive rate of P53 and Ki67 expression level in different degrees of HCC differentiation were statistically significant (P0.05). Multivariate logistic analysis showed that cirrhosis (OR=3.408), high expression of Ki67 (OR=11.113) and positive P53 (OR=9.711) were the main risk factors for poorly differentiated HCC.  Conclusion There are differences in clinical characteristics and expressions of Ki67 and P53 in HCC patients with different degrees of differentiation. Logistic regression analysis can identify clinicopathological risk factors affecting the degree of differentiation of HCC, which can provide criterion support for accurate diagnosis and prognostic treatment.

Effects of overexpression of Notch intracellular domain on proliferation and osteogenic differentiation of human periodontal ligament stem cells / 中华口腔医学杂志

Objective@#To investigate the effect of overexpression of Notch intracellular domain (NICD) on proliferation and osteogenic differentiation of human periodontal ligament stem cells (hPDLSC).@*Methods@#The third generation hPDLSC with stable overexpressing of NICD were assigned as experimental group, normal hPDLSC were as negative control group and hPDLSC transfected with empty vector were as blank control group. The effect of overexpressing NICD on proliferation ability of hPDLSC was detected by using cell counting kit-8 (CCK-8). Alizarin Red staining and real-time quantitative PCR (qPCR) were used to detect the effects of NICD on cementum attachment proteins (CAP), osteocalcin (OCN), Runt-related transcription factor 2 (RUNX2) and Notch signal pathway receptor Notch1. The effect of overexpressing NICD on hPDLSC osteogenic protein RUNX2 and flag marker protein (used to label NICD) were detected by using Western blotting.@*Results@#CCK-8 results showed that there were no significant differences in A values amongst the three groups for 1-2 days (P>0.05). The number of cells in the experimental group was significantly increase than that of the two control groups from the third to seventh days (A values were 0.203±0.016, 0.364±0.014, 0.449±0.020, 0.549±0.020 and 0.570±0.020, respectively) (P<0.05). Alizarin red staining showed that compared with the blank control group and negative control group, the mineralized nodules in the experimental group had smaller formation range and lighter color, and the differences were statistically significant (P<0.05). The expressions of CAP gene (0.751±0.058, 0.887±0.025), osteocalcin gene (0.592±0.051, 0.670±0.045) and RUNX2 gene (0.319±0.038, 0.684±0.055) at 14 and 21 days in the experimental group were significantly lower than those in the negative control group respectively (P<0.05). However, the expression levels of Notch1 gene at 14 and 21 days (2.507±0.047, 4.041±0.219) were significantly higher than those of negative and blank control groups (P<0.05). The results of Western blotting showed that the expressions of flag marker protein (0.167±0.007, 0.204±0.010) at 14 and 21 days in the experimental group were significantly higher than those in the negative and blank control groups (P<0.05). However, the expressions of RUNX2 protein (0.075±0.006, 0.074±0.013) at 14 and 21 days were significantly lower than that in the negative control group (0.092±0.003, 0.118±0.008) and blank control group (0.174±0.006, 0.212±0.008) (P<0.05).@*Conclusions@#Overexpression of NICD can promote the proliferation capacity of hPDLSC and inhibit its osteogenic differentiation.

Effect of tumor necrosis factor-α on the proliferation and multi-directional differentiation of stem cells from rat apical papilla / 重庆医学

Objective To evaluate the biological effect of tumor necrosis factor-α(TNF-α) on the proliferation and multi-directional differentiation of stem cells from rat apical papilla(SCAP).Methods SCAP was extracted by combining enzyme digestion method with tissue block method.The cells were divided into control group(TNF-α 0 ng/mL) and experimental group(TNF-α 5,10,20,50 ng/mL).The ability of proliferation of SCAP was measured by MTT method.The ability of osteogenic/dentinogenic differentiation of SCAP was measured by alizarin red staining and quantitative real-time PCR.The ability of adipogenic of SCAP was measured by oil red O staining.The expression of vascular related genes of SCAP was measured by quantitative real-time PCR.Results SCAP was consistent with the characteristics of mesenchymal stem cells and possessed the ability of multi-directional differentiation.The MTT results showed that experimental group promoted the proliferation of SCAP in comparison with the control group.The difference was statistically significant(P<0.05),and 10 ng/mL was the optimum concentration.The results of alizarin red staining showed that with the increase of the concentration of TNF-α,the mineralized nodules in the experimental group gradually became smaller,and the number of the formation decreased gradually.The results of quantitative real-time PCR showed that the expression of OC,DMP-1 and DSPP in the experimental group was significantly lower than that of the control group at 3 and 7 days,in which the expression of OC was statistically significant different(P<0.05);at 14 days,the expression of OC,DMP-1 in the experimental group was significantly lower than that of the control group(P<0.05).The result of Oil red O staining showed that with the increase of the concentration of TNF-α,the lipid droplets formation in the experimental group gradually decreased.The result of quantitative real-time PCR showed that the expression of ANGPT1,VEGFA,PECAM-1 in the experimental group was significantly lower than that of the control group(P<0.05).Conclusion TNF-α might promote the proliferation and inhibit the multi-directional differentiation of SCAP.

Correlation of alveolar bone structure and incisor labial inclination in adolescents with skeletal class II malocclusion of Uygur and Han populations in Xinjiang, China / 中国组织工程研究

BACKGROUND:Location relationship between maxilary incisor labial inclination and the thickness of anterior alveolar bone displays ethnic and regional differences. OBJECTIVE:To study the correlation of alveolar bone structure and incisor labial inclinationin adolescents with skeletal class II malocclusion in Uygur and Han populations of Xinjiang, China. METHODS:Sixty Uygur and 60 Han patients at 11-16 years of age (average 13.8 years old), 32 males and 28 females, with skeletal class II malocclusion wereincluded. The thickness of anterior alveolar bone and incisor labial inclination were measuredon lateralcephalometric films, and the results were analyzed using SPSS 17.0 statistical software. RESULTS AND CONCLUSION:In Han and Uygur populations, palatalalveolar bone thicknessin maxilary incisor regionwas significantly negatively correlated with the inclination of maxilary incisor (r=-0.715 for Han,r=-0.651 for Uygur,P< 0.05), while labial alveolar bone thicknessin mandibular incisor regionwas significantly positively correlated with the lower incisor inclination (r=0.902 for Han,r=0.745 for Uygur,P< 0.05). These results indicate thatthepalatal alveolar bone thicknessin maxilary incisor region decreases with the increase of the inclinationof maxilary incisor; however,thelabial alveolar bone thicknessin mandibular incisor regionincreases with the increase of the lower incisor inclination.

Biological properties of human periodontal ligament stem cells under inflammatory microenvironment / 中国组织工程研究

BACKGROUND:The periodontal ligament stem cels can promote periodontal tissue regeneration, providing a new way for the treatment of periodontitis. OBJECTIVE:To observe the inflammatory microenvironment effects on the biological properties of periodontal ligament stem cels. METHODS: Periodontal ligament stem cels from healthy controls and patients with periodontitis were primarily cultured by tissue digestion method, purified using limited dilution method, and identified through detection of CD146 and STRO-1. Then, passage 3 cels were taken and denoted as normal control and inflammation groups folowed by osteogenic induction. RESULTS AND CONCLUSION:Purified cels from two sources both expressed STRO-1 and CD146. Periodontal ligament stem cels in the inflammation group showed higher multiplication capacity, but the osteogenesis ability was lower compared with the normal control group. The expressions of Runx2 mRNA and Osterix mRNA were dropped significantly after the stimulus of tumor necrosis factor-α (P < 0.05), but the interleukin-1β and interleukin-6 did not have a significant impact. Tumor necrosis factor-α at 0.1 and 1 μg/L had no significant effects on the expression of Runx2 mRNA, but the expression of Runx2 mRNA was decreased significantly after treatment with 10 μg/L tumor necrosis factor-α (P< 0.05). It is confirmed that the molecular signaling mechanism inside the periodontal ligament stem cels is changed under inflammatory microenvironment, so that the differentiation capacity of cels from the inflammatory sources is lowered. Moreover, tumor necrosis factor-α is one of the key factors and its optimalconcentration is 10 μg/L.

Alveolar bone defect repair using autologous bone marrow mesenchymal stem cells combined with platelet-rich fibrin / 中国组织工程研究

Abstract BACKGROUND: Alveolar bone deficiency wil not meet aesthetic and functional requirements for dental implants. OBJECTIVE:To observe the repair effect of passage 3 autologous bone marrow mesenchymal stem cels (BMSCs) and platelet-rich fibrin (PRF) on alveolar bone defects in rabbits. METHODS:Twenty-seven New Zealand rabbits were randomly divided into BMSCs/PRF group, PRF group and model group (n=9 per group). The left mandible incisors were extracted in al the rabbits under general anesthesia. BMSCs/PRF group was immediately implanted BMSCs/PRF composite into the alveolar socket, PRF group only implanted PRF, and model group implanted nothing. RESULTS AND CONCLUSION: In the model group, the alveolar crest and alveolar mucosa become sunken notably and narrowed. In the BMSCs/PRF and PRF groups, the thickness of alveolar bone wal, alveolar bone width, alveolar bone height difference, and bone mineral density were al increased, especialy in the former group. In addition, the trabecular arrangement was better in the BMSCs/PRF groups than the model and PRF group. Our findings indicate that alveolar socket filing with composite of BMSCs and PRF can achieve preservation of alveolar bone width and height after tooth extraction in rabbits.

Stem cells from the apical papilla versus periodontal ligament stem cells：biological behaviors / 中国组织工程研究

BACKGROUND:Stem cels from the apical papila are a new kind of mesenchymal stem cels, and whether it can be used in root regeneration is the key to the present study. OBJECTIVE:To culture rat stem cels from the apical papila and periodontal ligament stem celsin vitro, and to compare the biology behaviors of these two kinds of cels, thereby providing experimental basis for the application of stem cels from the apical papila in root regeneration. METHODS:The apical papila, as wel as the periodontal ligament tissues from the healthy mandibular teeth of young rats were digested and cultured. Immunophenotypes of stem cels from the apical papila and periodontal ligament stem cels were detected by immunofluorescence technique. Then, cel growth curves were determined by MTT method and mineralized nodule formation was observed by alizarin red staining. RESULTS AND CONCLUSION:Stem cels from the apical papila and periodontal ligament stem cels were both positive for STRO-1. Stem cels from the apical papila were positive for CD90 and weakly positive for CD146. Periodontal ligament stem cels were positive for CD146 and weakly positive for CD90. The absorbance values of stem cels from the apical papila and periodontal ligament stem cels increased with the increasing of time and became stable at 8 days. Since the 4th day, the proliferation capacity of stem cels from the apical papila was significantly stronger than that of periodontal ligament stem cels (P < 0.05). Both of stem cels are visible to have mineralized nodule formation. Compared with the periodontal ligament stem cels, stem cels from the apical papila were stained obviously deeper and had more mineralized nodules. These results show that stem cels from the apical papila have stronger proliferation capacity and mineralization ability than periodontal ligament stem cels. Cite this article:Zhao L, Yu L, Yuan P, Zhou CM, Wu PL.Stem cels from the apical papila versus periodontal ligament stem cels: biological behaviors. Zhongguo Zuzhi Gongcheng Yanjiu. 2016;20(1):113-117.

The expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects in rabbits with bone marrow stem cells compounded with platelet-rich fibrin / 华西口腔医学杂志

<p><b>OBJECTIVE</b>We explored the expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects by establishing animal models with a composite of autologous bone marrow mesenchymal stem cells (BMSCs) and platelet-rich fibrin (PRF) to repair bone defects in the extraction sockets of rabbits.</p><p><b>METHODS</b>A total of 36 two-month-old male New Zealand white rabbits were randomly divided into four groups, and the left mandibular incisors of all the rabbits were subjected to minimally invasive removalunder general anesthesia. BMSC-PRF compounds, single PRF, and single BMSC were implanted in Groups A, B, and C. No material was implanted in Group D (blank control). The animals were sacrificed at 4, 8 and 12 weeks after surgery, the bone defect was immediately drawn, and the bone specimens underwent surgery after four, eight, and twelve weeks, with three rabbits per time point. The expressions of Notch1 and Wnt3a in the repair process of the bone defect were measured via immunohistochemical and immunofluorescence detection.</p><p><b>RESULTS</b>Immunohistochemistry showed that the expressions of Notch1 and Wnt3a in Groups A, B, and C were higher than that in Group D at the fourth and eighth week after operation (P<0.05). By contrast, the expressions of Notch1 and Wnt3a in Group D were higher than those in Groups A, B, and C at the twelfth week (P<0.05). Immunofluorescence showed that the expressions of both Notch1 and Wnt3a reached their peaks in the new bone cells of the bone defect after four weeks following surgery and gradually disappeared when the bone was repaired completely.</p><p><b>CONCLUSION</b>Notch1 and Wnt3a signaling molecules are expressed in the process of repairing bone defects using BMSC-PRF composites and can accelerate the healing by regulating the proliferation and differentiation of BMSCs. Moreover, the expressions of Notch and Wnt are similar, and a crosstalk between them may exist it.</p>

Fracture resistance of different post-and-core repair systems after warm gutta filling / 中国组织工程研究

BACKGROUND:Due to the complexity and irregularity of bypass obturation of oval root canal and the particular stress of the post and core to the tooth, we have not yet found a reasonable post crown for dental restoration after bypass obturation of the oval root canal. OBJECTIVE:To compare the flexural capacity of the three kinds of post-and-core repair systems (cobalt-chromium cast post and core, zirconium oxide post and core, and CAD/CAM-fabricated glass fiber post and core) after bypass obturation of the oval root canal warm gutta. METHODS: Ninety mandibular first premolars were selected for bypass obturation of the root canal with Obtura II & System B, and then randomized into three groups that were respectively restored with cobalt-chromium cast post and core, zirconium oxide post and core and CAD/CAM-fabricated glass fiber post and core. After that, cobalt-chromium metal crown was used for ful-crown restoration. Fracture strength and fracture type were recorded in different groups. RESULTS AND CONCLUSION: The fracture resistance was higher in the cobalt-chromium cast post and core group and zirconium oxide post and core group than the glass fiber post and core group (P < 0.05), and the former two groups had no significant difference. Cobalt-chromium cast post and core was fractured at the root of tooth, and could not be repaired; the zirconium oxide post and core was fractured at the root neck and root of tooth, which was confirmed as reparative fracture; the glass fiber post and core was fractured at the tooth neck, which could be restored. These findings indicate that the cobalt-chromium cast post and core can bear greater occlusal force, but has a higher probability of root fracture; the CAD/CAM-fabricated glass fiber post and core exhibits a lower probability of root fracture

Changes of root surface temperature generated by different bypassing warm gutta-percha obturation methods / 中国组织工程研究

BACKGROUND:Obturation with warm gutta-percha can achieve perfect three-dimensional root canal obturation effect. Due to specific structure of oval canal, particularly in the bypass preparation process, excessive cutting of local tooth tissue may lead to tooth tissue thinning and irregular shape. The separation equipment is the metal with good heat conduction, so the heat caused by the bypassing warm gutta-percha obturation would burn periodontal tissue remains controversial. OBJECTIVE:To investigate the changes of root surface temperature produced by two bypassing warm gutta-percha obturation for the separation instrument in oval canalin vitro by using infrared thermography. METHODS:Forty mandibular first premolars were harvested from oval canals, and were separated using stainless steel 15# K file at apical 3 mm, with the length of 3 mm. The root canal bypassing was prepared using TF nickel-titanium file under operating microscope. The teeth were randomly divided into two groups, with 20 teeth in each group, and were obturated with the Thermafil warm gutter-percha and E&Q plus warm gutta-percha vertical compaction, respectively. An infrared thermoviewer was used to measure the external root surface temperature before and after the obturation. RESULTS AND CONCLUSION:Two warm gutta-percha obturation methods used for separating instruments bypassing in the oval root canal, had both caused the rise of root surface temperature, which was less than 10℃. In the Thermafil group, the temperature changes were 3.2-8.1℃ and the average change was 4.97℃. In the vertical condensation group, the temperature changes were 5.5-9.8℃ and the average change was 7.35℃. There were significant differences in the change of root surface temperature between the two groups (P < 0.05). Thermafil warm gutter-percha obturation would increase the root surface temperature, but cannot damage periodontal tissues. It is more secure than warm gutta-percha vertical condensation.

Effect of Varnish XT and ICON resin infiltration treatment on the microhardness of white spot lesions / 中国组织工程研究

BACKGROUND:In the treatment of early caries, fluoride can be used for remineralization of white spot lesions. Varnish XT (durable fluoride-releasing coating) and ICON penetration resins are two new materials. Varnish XT as a new type of resin reinforced glass ionomer can be selected as mineralized material. ICON penetration resin is a high-permeability resin with good liquidity that can infiltrate by capilary action into the pores created by enamel demineralization. Low-viscosity resin is used to replace the lost hard tissue due to demineralization and occupy the micropores, so as to fil the region of enamel demineralization and prevent further development of lesions. OBJECTIVE:To study the effects of two minimaly invasive surgical treatment materials, Varnish XT and ICON penetrating resin, on the microhardness of enamel caries white spot. METHODS:Totaly 100 incisors of cows were selected, embedded with ethoxyline resin and polished. The lip side facing down served as the observation side. An area of at least 6 mm×10 mm on the enamel face was exposed, and there were five regions from incisal to dental cervix, A, B, C, D, E. After demineralization liquid for artificial caries, no treatment was adopted in region A, treatment with Varnish XT was for region B, treatment with ICON penetrating resin for region C, treatment with fluoride for region D, and region E was sealed with antacid nail. Surface micro-hardness was detected. RESULTS AND CONCLUSION: After demineralization, surface micro-hardness of regions A, B, C, D decreases remarkably as compared with region E (P B and D for surface micro-hardness with statistical significance (P 0.05). ICON resin infiltration, Varnish XT and fluoride have obvious improvement effects on surface micro-hardness, and ICON resin infiltration is superior to Varnish XT and fluoride.

Effect of platelet-rich fibrin released transforming growth factor beta 1 on the proliferation of bone marrow mesenchymal stem cells in vitro / 中国组织工程研究

BACKGROUND:Bone marrow mesenchymal stem cel s are the ideal cel s for tissue repair. Whether the ability of in vitro proliferation can be enhanced is a key factor to promote tissue repair. OBJECTIVE:To observe the effect of transforming growth factorβ1 on the proliferation of bone marrow mesenchymal stem cel s in vitro. METHODS:Blood samples were taken from the central artery of rabbits to prepare platelet-rich fibrin by centrifugation method which was then placed into fresh DMEM at 37℃for 7, 14, 21, 28 days to col ect exudates. The mass concentrations of transforming growth factor-β1 in the exudates of platelet-rich fibrin were detected. Rabbit bone marrow mesenchymal stem cel s were col ected and cultured in the conditioned medium made by the exudates of platelet-rich fibrin, and the proliferation of cel s was observed. RESULTS AND CONCLUSION:Concentration of transforming growth factorβ1 was increased with time increasing, increased fastest at 21-28 days, and peaked at 28 days. Under the same stimulus concentration, the proliferation of bone marrow mesenchymal stem cel s was reduced at 0-1 day, increased obviously at 1-2 days, and entered into a steady phase at 2-3 days. Under 150 ng/L transforming growth factorβ1, bone marrow mesenchymal stem cel s proliferated fastest. Experimental findings indicate that with the increase of time, the concentration of transforming growth factorβ1 in the exudates of platelet-rich fibrin increase gradual y, and the conditioned media containing different concentrations of transforming growth factorβ1 play different roles in promoting the proliferation of bone marrow mesenchymal stem cel s. Bone marrow mesenchymal stem cel s cultured in the conditioned medium containing 150 ng/L transforming growth factorβ1 for 2-3 days can proliferate fastest.

Establishment of a three-dimensional finite element model of transmission straight wire appliance / 中国组织工程研究

BACKGROUND:With the development of modern orthodontics, to invent an efficient appliance is the focus in recent studies. Transmission straight wire appliance was born on this background. This appliance can accelerate occlusion and shorten treatment duration. The relationship between distal width and angulation of gable bends of main arch wire needs to study in depth. OBJECTIVE:To establish three-dimensional finite element model of transmission straight wire appliance with better biological and mechanical similarity, and to obtain the relationship between distal width and angulation of gable bend of main arch wire. METHODS:By using scanning of spiral CT with 64 rows, the sectional image data in DICOM format of maxil ary dentition and maxil ae of the volunteers (Class Ⅱ, division 1) were obtained. With the help of Ansys workbench 13.0, Mimics 10.01, Unigraphics NX and Geomagic Studio 8.0 softwares, the three-dimensional finite element model including transmission straight wire appliance, bend, Australian Orthodontic Wire, maxil ae, maxil ary tooth and periodontal ligament was established in Windows XP Service Pack 3 system. RESULTS AND CONCLUSION:A three-dimensional finite element model of transmission straight wire appliance was established, which consisted of 250 929 elements and 657 766 nodes. Furthermore, three-dimensional finite element model had higher geometric similarity and mechanical similarity, as wel as the advantages of adding or subtracting components according to the requirement of the research. The model was conductive to analyze the mechanical system of transmission straight wire appliance and guide the clinical application and appliance modification.

Effectiveness of filling ex vivo mandibular central incisor using bypassing root canal preparation with two kinds of warm gutter fillings and cold lateral condensation technique / 中国组织工程研究

BACKGROUND: The filling compactness can not be guaranteed due to apparatus retention in traditional lateral condensation.The warm gutter filling can achieve good results because of the easy changeable of gutta-percha in softening states.OBJECTIVE: To compare the warm gutta-percha fillings (Obtura Ⅱ and BeeFill 2 in1 filling) and cold lateral compacted gutta-percha with the bypassing root canal preparation in the intracanal separated instrument of oval canal.METHODS: Firstlythe 60 oval root canals of fiat mandibular central incisors were randomly divided into three groups, with 20 teeth in each group. After that, the root canal was filled with BeeFill 2 in1, Obtura Ⅱ condensation, and lateral condensation.The percentage of void at 5-mm to root tip versus cress section area was observed under a scanning electron microscope.RESULTS AND CONCLUSION: Under in vitro condition, the difference of percentage of void area versus root canal area between the Obtura Ⅱ condensation group and the lateral condensation group had significance (P=0.013), and the similar difference could be found between the BeeFill 2 in1 condensation group and the lateral condensation group (P=0.014), but the difference had no significance between the BeeFill 2 in1 condensation group and the Obtura Ⅱ condensation group (P=0.088).The results revealed that the root canal can be sealed accurately when establish hypass root next to the separated instrument and filled with BeeFill 2 in1 warm gutter filling.

Expression of hTERT mRNA in salivary gland tumors / 实用口腔医学杂志

Objective:To investigate the expression of human telomerase reverse transcriptase(hTERT)gene in salivary gland tumors and to study its clinicopathological significance.Methods:In situ- mRNA hybridization method was used to detect the expression of hTERT mRNA in 10 cases of normal salivary gland tissues, 30 of benign salivary gland tumors and 43 of malignant salivary gland tumors.The relationship between hTERT mRNA expression and sex,age, tumor size, location, histologic differentiation of the malignant tumors was analyzed by using ?2 test.Results:hTERT expression was negative in all normal tissues. Positive rate of hTERT mRNA expression was 3.3%(1/30) and 83.7%(36/43) in benign and malignant salivary gland tumors respectively(P0.05).Conclusion:hTERT mRNA expression may be used to distinguish malignant salivary gland tumors from benign.

Reducing bacterial aerosols by dental procedure with Xipayi mouth rinse or H_2O_2 pre-rinse / 实用口腔医学杂志

Aerosol and splatter formed during dental procedure were collected pre and post rinsing with Xipayi mouth rinse or 1% H2O2,cultured 48 hours with blood agar plates,counted the bacterial colonies.Both groups were effective in reducing bacterial aerosols(P 0.05).Bacterial aerosols by dental procedure can be reduced by using mouthwash pre-operationally,both Xipayi mouth rinse and 1% H2O2 are effective mouthwashes.