Root canal therapy is the most efficient way to treat pulptitis and periapical inflammation, which can clear infections of root canal systems, fill the root canal firmly, and avoid reinfection. However, the variations in root canal morphology and complexity of infection confer difficulty in thoroughly eliminating microorganisms and their by-products in the root canal system, especially in the root apex area (including the top one-third of the root canal and periapical tissue), which is described as the hardest area to clean during endodontic treatment. Infection is difficult to remove entirely because the apex area is hard to approach using dental instruments and because of the existence of special morphological structures, such as apical ramification, intercanal anastomoses, and lateral branch of root canal. This review gives a brief introduction of the characteristics and difficulties of apical infection and knowledge on how to control such infections, including root apex preparation, irrigation and disinfection, and root canal filling.
Dental Pulp Cavity ; Humans ; Infection Control ; Periapical Periodontitis ; Root Canal Filling Materials ; Root Canal Irrigants ; Root Canal Obturation ; Root Canal Preparation ; Root Canal Therapy

In order to gain the strain which has high growth vigor and whose biomass concentration satisfy further fermentation to produce arachidonic acid, we took the yield of microbes olein and arachidonic acid as evaluative index, adopted twice ultraviolet mutation, determined the time of ultraviolet irradiation by single factor expriment, and then the content of the arachidonic acid was measured by GC. The results of this experiment showed that the power of viltalight lamp was 20 W, exposure distance was 30 cm and exposure time was 80 s, lethality of spores of Mortierella isabellina was 76.4%. After twice ultraviolet mutation and repeatedly screen, a mutation of Mortierella isabellina Z80s2-109 whose arachidonic acid concentration in biomass were 3.77 times of the control strains was obtained and genetic stability.

Objective To investigate the influence of all-round intervention on the quality of life and the emotion of cancer patients who have accepted the gamma knife therapy. Method Using health education, psychotherapy and the behavior treatment for 260 patients with malignant tumor who had accepted the gamma knife therapy. Evaluated the quality of life and the emotion of these patients before and after the intervention respectively by using questionnaire of QOL, SCL-90, SDS and SAS. Results The values of indicated the QOL, SCL-90, SDS and SAS before the all-round intervention were 23.12?4.68, 68.12?33.26, 40.12?10.28 and 42.48?12.16 respectively. The values which had obtained after the all-round intervention were 46.26?3.28, 36.12?26.23, 28.16?5.23 and 26.12 ?10.66 respectively, there were significant differences between them,P

China ; Coronary Artery Bypass ; methods ; Coronary Artery Disease ; surgery ; Humans

Objective To investigate the relationship between interleukin-17 (IL-17) and vitiligo.Methods Totally,32 vitiligo patients and 30 healthy human controls were enrolled in this study.Blood samples were collected from all the subjects,and enzyme-linked immunosorbent assay (ELISA) was performed to determine the plasma levels of IL-17.The relationship of plasma IL-17 levels with disease stage,clinical course and lesion area was assessed.Results The plasma levels of IL-17 were significantly higher in the patients with progressive and stable vitiligo than in the healthy controls (both P ＜ 0.05),and higher in the patients with progressive vitiligo than in those with stable vitiligo (P ＜ 0.05).Moreover,the plasma levels of IL-17 were positively correlated with the area of vitiligo lesions (r =0.456,P ＜ 0.05),but unrelated to the clinical course of vitiligo (r =0.239,P ＞ 0.05).Conclusion IL-17 may play a certain role in the occurrence and development of vitiligo.

Objective To construct an expression plasmid carrying the specific siRNA of survivin gene,and to evaluate its silencing effect on the expression of survivin gene and its inhibition effect on the growth of gastric cancer cells.Methods The specific siRNA of survivin gene was designed and synthesized,and an expression plasmid pAdGFP-siRNA was constructed.Gastric cancer cell line SGC-7901 was cuhured and transferred with pAdGFP-siRNA,then the silencing of survivin gene expression and the growth inhibition of cancer cell mediated by pAdGFP-siRNA were identified.Results The growth of gastric cancer cells was inhibited after transferring the pAdGFP-siRNA,with the inhibition rate of 68.2% compared to the control group.Immunohistochemistry showed that the specific siRNA markedly silenced the expression of survivin gene in cancer cells.Conclusions The overexpression of survivin gene in gastric cancer cells results in the high proliferation and the resistance to the chemo- and radio-therapy of the cancer cells.The specific siRNA can markedly silence the expression of survivin gene and inhibit the growth of cancer cells.

OBJECTIVETo investigate the relationship between expression of angiogenic factors and invasion and proliferation of pancreatic cancer cell.

METHODSThe three pancreatic cancer cell lines of SW1990, Panc-1 and PCT-3 were divided into four groups respectively: control group, VEGF siRNA group, bFGF siRNA group and VEGF siRNA + bFGF siRNA group. The expression and the secretion of VEGF and bFGF in the three cell lines were inhabited by VEGF siRNA and bFGF siRNA. The proliferation and the invasion of the three cell lines were determined by CCK-8 and Boyden Chamber invasion tests.

RESULTSExpressions of VEGF and bFGF in three cell lines were significantly inhibited by VEGF siRNA and bFGF siRNA. The proliferation was inhabited by VEGF siRNA and bFGF siRNA in SW1990 and Panc-1 (P < 0.05), while was not in PCT-3 (P > 0.05). The invasion was inhabited significantly by VEGF siRNA and bFGF siRNA in the three cell lines (P < 0.05). Combination of VEGF siRNA and bFGF siRNA resulted in more efficient influence in inhibition of invasion in Panc-1 and proliferation in PCT-3 and SW1990 than VEGF siRNA or bFGF siRNA individually.

CONCLUSIONThe decreased expression of VEGF and bFGF can inhabited the ability of invasion and proliferation of pancreatic cancer cell.

Cell Line, Tumor ; Cell Proliferation ; Fibroblast Growth Factor 2 ; genetics ; Humans ; Neoplasm Invasiveness ; Pancreatic Neoplasms ; pathology ; RNA, Small Interfering ; genetics ; Vascular Endothelial Growth Factor A ; genetics

A strain of high-efficiency bioflocculant-producting bacteria,which was named TJ-3,was screened from sewage sludge.The strain was gram-negative and rod-shaped in physiological biochemical test and was identified as Pseudomonas aeruginosa by 16S rDNA Sequencing.According to the growth curve of the TJ-3 strain,the growth stabilization period is long so that Microbial Flocculants(MBF) production is stable.The MBF produced by the TJ-3 strain is able to flocculante kaolin suspension with 98.2%.The MBF activity distribution tests show that most of the active components of the bioflocculant exist in deposition after centrifufation.When pH is 8.5,1%(quality fraction) CaCl2 Solution dosing quantity is 3.5 mL,bioflocculant dosing quantity is 1.5 mL in 100 mL kaolin suspension,the bioflocculant has an optimal flocculation.

According to morphological and microscopic characteristics, a high-efficient decolorizing fungus, the strain Asaw117, was identified as Aspergillus awamori. Selecting eight different dyes from Azo dyes, anthraquinones dyes and oxygen Quinones dyes, the decolorizing assays of various dyes showed that the strain Asaw 117 was the highest decolorizing potential to 0.1 g/L Vat Blue RSN, the discoloration rate up to 100 percent. Comparing to different kinds of medium and several of carbon and nitrogen sources, the strain had the best decolorizing efficient although grew slower in the Czapek medium, otherwise, grew quicker and decolorizing efficient lower in the PDF medium. It could use Vat Blue RSN as a nitrogen source, but not as a carbon source. The medium composing of saccharose and ammonium nitrate as carbon and nitrogen sources was decolorizing potential markedly during different combinations of carbon and nitrogen sources. So the strain has good potential for the dyeing wastewater treatment

Objective To investigate the effects of low frequency ultrasound (LFU) on the proliferation and apoptosis of smooth muscle cells (SMCs) in rabbits with carotid atherosclerosis(CA).Methods CA models were established in 30 New Zealand rabbits using a high fat diet and air-drying.They were randomly divided into a control group and four LFU groups:group A received 0.5 W/cm~2 LFU for 5 min/d,group B 0.5 W/cm~2 for 10 min/d, group C 1 W/cm~2,5 min/d,and group D 1 W/cm~2,10 min/d.The rabbits' carotid arteries were autopsied after 20 d of the LFU treatment.The expression of PCNA and TUNEL staining were used to explore the proliferation and apopto- sis of SMCs,and the proliferation rates (PRs) and apoptosis rates (ARs) were calculated.Results Compared with the control group,the PRs in groups B,C and D were significantly lower,while the ARs in groups B,C and D were significantly higher.There was no significant difference in ARs or PRs among groups B,C and D.Con- clusion LFU can induce SMC apoptosis and inhibit SMC proliferation in rabbits with CA.