OBJECTIVE To study whether immunosuppressant(IS,cyclophosphamide,CPA) have the function of prevention and treatment of congenitalautoimmune sensorineural hearing loss or not.METHODS The female guinea pigs were immunized by crude conspecific inner ear antigens(CIEAgs),and took orally IS or not at the same time during gestation.Then the pregnant guinea pig's and their offspring's hearing function were measured and inner ear histopathologic changes were observed.Some of offspring borne by the female guinea pigs which immunized with CIEAgs and not treated with IS showed hearing loss and were treated by IS,and their hearing functions were measured and inner ear histopathologic changes were observed with same techniques.RESULTS After immunizing with CIEAgs,some of female guinea pigs which immunized with CIEAgs and not treated with IS showed different degrees of hearing loss(the thresholds of acoustic nerve compound active potential and cochlear microphonic potentials elevated) and immune inflammations in inner ear tissues.All females guinea pigs in experimental group which immunized with CIEAgs and treated with IS at same time,and their offspring have no any hearing loss and inner ear histopathologic changes.After IS therapy,the hearing function improved(mainly at the low-frequency region) in some offspring guinea pigs,which borne by the female guinea pigs which immunized with CIEAgs and not treated with IS.CONCLUSION IS could effectively prevent offspring's congenital sensorineural hearing loss induced by their mother's special antibodies against inner ear tissues antigens.IS showed effective result for treatment of congenitalautoimmune sensorineural hearing loss,but the curative effect was limited.

Objective: Cell cycle has recently become more appealing as a new target of anti-carcinogen-ic agent. Diallyl disulfide (DADS) inhibits growth and induces call cycle G_2/M arrest in human gastric cancer BGC823 cells. Cell division cycle protein 25C (Cdc25C) and CyclinB1 expression are involved in G_2/M arrest.However, mechanisms of G_2/M arrest are not yet fully understood. The aim of this study was to elucidate the mechanism of cell cycle G_2/M arrest in human gastric cancer BGC823 cells induced by DADS. Methods: The expression of chk1 and Chk2 mRNA associated with cell cycle arrest of BGC823 cells after the induction with DADS for 1 or 2 days was detected by RT-PCR. The protein expression of cycle-related proteins ATM-RAD3-related gene (ATR), checkpoint kinase1 (Chk1), checkpoint kinase 2 (Chk2), P-ATR, P-Chk1 and P-Chk2 was measured by Western blot. Interaction between Chk1/2 and Cdc25C was analyzed by immuno-precipitation. Results: After the cells were treated with 15 mg/L DADS for 1 or 2 days, the expression of Chk1 and Chk2 mRNA was not significantly different from that in untreated cells (P>0.05). Western blot analysis showed that the expression of total Chk1 and Chk2 treated with 15 mg/L DADS was not significantly different from that in untreated cells. But phospho-chk1 showed a significant increase after stimulation with 15 mg/L DADS for 2h to 12h and continued to increase gradually as time went on (P<0.05). Phospho-Chk2 showed a eak expression and a weaker expression after stimulation with DADS, but the changes were not statistically significant (P>0.05). Addition of 15 mg/L DADS to BGC823 cells for 15 rain to 120 min resulted in an increase in phospho-ATR expression, whereas no changes were found in ATR expression (P<0.05). The Chk1 Ab in-creasingly precipitated Cdc25C in BGC823 cells treated with DADS (P<0.05). In contrast, Chk2 Ab failed to change precipitation with Cdc25C by DADS (P>0.05). Conclusion: Activation of chk1 was involved in cell cy-cle G_2/M arrest in BGC823 cells treated with DADS. Cell cycle G_2/M arrest by DADS is associated with phos-phorylation of several cell cycle regulatory proteins including ATR and Chk1 which regulate expression of Cdc25C.

SMART-RACE was performed after isolating the total RNA of Armillariella tabescens to amplify the full-length cDNA of arabinosidase (GenBank Accession No. AJ620046). Bioinformatics analysis was used to analyze the code frame of arabinosidase, to predict its structure and function. Recombinant plasmid pPIC9-AF was constructed and then electroporated into methylotrophic yeast Pichia pastoris GS115. The secreted 6 ? His fusion protein was purified to analyze its enzymology property. This arabinosidase had high activity at 30-35℃ under acid condition, and was stable within wide range of pH and temperature. It maintained about 80% activity at the range of pH4. 0-8.0 and 20-40℃,wider than many other cloned arabinosidase. So it was worthy to go step further to study this enzyme, and recombinant expression provided a chance of highly expressing arabinosidase.

OBJECTIVEThe micronucleus test was applied to evaluate the genotoxicity of a new nanocomplex HA-PA66 root filling material in vitro.

METHODSThe dulbecco's modified eagle media(DMEM) extracts of the powder part and the mixture of the new nanomaterial were prepared separately. The V79 cell was used as the test cell and the mitomycin C(MMC) as the positive control. The MTT assay was employed in our study to evaluate the cytotoxic effect while the number of micronucleus was used as the criteria for the detection of genotoxocity.

RESULTSThe MTT values in test groups and negative group were not significantly different at different times (P > 0.05). The number of micronucleus in test groups (powder group: 6.1 +/- 1.1/1,000; complex group: 5.7 +/- 0.6/1,000) was similar to the negative control(5.3 +/- 0.8/1,000, P > 0.05), while they were significantly different to the positive control(123.9 +/- 8/1,000, P < 0.05).

CONCLUSIONThe new nanocomplex HA-PA66 root filling material showed no detectable cytotoxic and genotoxic effects in this study and was proved to be biocompatible.

Animals ; Biocompatible Materials ; toxicity ; Cricetinae ; Cricetulus ; Durapatite ; toxicity ; Micronucleus Tests ; methods ; Mutagenicity Tests ; methods ; Nanotechnology ; Nylons ; toxicity ; Root Canal Filling Materials ; toxicity

OBJECTIVETo study the effect of hepatocyte growth factor on the proliferation of dental pulp cell.

METHODSThe 4th generation dental pulp cell cultured in vitro was used as target cell. 1- 200 microg/L hepatocyte growth factor was added in the test group while the pure cell culture DMEM as control. The MTT method and flowcytometry were applied to assay the proliferation and cell cycle of dental pulp cell of different groups.

RESULTS1-200 microg/L hepatocyte growth factor showed promoting effect to the proliferation of pulp cell since the 5th day (P < 0.05). 100 microg/L was found to be the optimal concentration. Also on the 5th day, 100 microg/L hepatocyte growth factor decreased the G1 subcycle and increased the S subcycle of dental pulp cell ( P < 0.05). While on the 3rd day, it had no effect on the cell cycle.

CONCLUSIONHepatocyte growth factor had positive effect on the proliferation of dental pulp cell, with 100 microg/L as the optimal concentration.

Cell Culture Techniques ; Cell Proliferation ; Dental Pulp ; Epithelial Cells ; Hepatocyte Growth Factor ; Humans

Objective To understand the genetic polymorphism of Salmonella and Staphylococcus aureus in Guangdong province, as well as to explore methods for identifying and tracing the source of these two foodbome pathogens. Methods Using the automated ribotyping system, two foodbome pathogens were tested with either EcoR Ⅰ or Pvu Ⅱ restriction enzymes. BioNumerics software was then applied for image analysis, database establishment and other corresponding analysis. Results Digestion of 32 Salmonella isolates with Pvu Ⅱ yielded 19 different ribotypes,and digestion of 14 Salmonella isolates with EcoR Ⅰ yielded 2 different ribotypes. Staphyloccus aureus isolates showed greater genetic diversity, whereas EcoR Ⅰ digestion of 49 different isolates yielded 31 different ribotypes. Conclusion Unique Salmonella and Staphylococcus aureus isolates could be identified through ribotyping. Although Salmonella serotyping and ribotyping were not strongly correlated, the combination of both restriction enzymes could be used to more effectively identify the genetic relationship among different strains as well as the source of food poisoning. Thus, not only could the genetic relationships amongst the different strains be inferred through ribotyping skills, the source of food poisoning and mode of transmission could also be determined under the use of this method.

OBJECTIVETo investigate the relationship between cytochrome P4501A1 (CYP1A1) Msp I gene polymorphism and childhood acute leukemia (AL).

METHODSRelevant literature was extensively searched and screened by Pubmed and Wanfang Database, Chinese Science Journal Database and Chinese Journal Net. Various data consolidation, combined OR values and their 95% CI were tested by RevMan 4.2; Funnel plots were used for the bias analysis.

RESULTSSix related literatures were found to meet the requirements. According to heterogeneity results, there was no significant difference in homozygous types(P>0.05), while there was significant difference in two others types (P all<0.05). For wild CYP1A1MspI homozygous for the reference group, Combined OR of heterozygous mutation, homozygous, heterozygous + homozygous mutation in AL and control groups were 1.18, 0.96, and 1.10 respectively. Subgroup analysis: Z values of CYP1A1MspI homozygous, heterozygous + homozygous in the acute lymphoblastic leukemia (ALL) and the control group were 0.10 and 0.76 respectively, Z values in non-acute lymphoblastic leukemia and control group were 0.74 and 0.75.

CONCLUSIONThere is no correlation between CYP1A1MspI gene polymorphism and the susceptibility of childhood AL.

Acute Disease ; Child ; Cytochrome P-450 CYP1A1 ; genetics ; Genetic Predisposition to Disease ; Heterozygote ; Humans ; Leukemia ; enzymology ; genetics ; Polymorphism, Genetic

OBJECTIVEThe purpose was to analyze the effects of three sterilization methods (dry heat sterilization, steam sterilization, and chemical sterilization) on the corrosion of dental fissure bur.

METHODS200 dental fissure burs were distributed to 10 groups. Bending strength, elastic modulus, and torsional strength were measured by bending and torsional instrument and calculated with special designed software. Among the three sterilization methods, the steam sterilization group showed the most evident.

RESULTSThe corrosion was most severe in steam sterilization group, followed by chemical sterilization, dry heat sterilization. With the sterilization time increased, bending strength, elastic modulus, and torsional strength decreased respectively. Of the three sterilization methods, the mechanical properties were decreased most evidently by steam sterilization, followed by chemical sterilization and dry heat sterilization.

CONCLUSIONIt is proved that the bending strength, elastic modulus and torsional strength have a tight relationship with the corrosion of dental fissure burs. The corrosion was most severe in steam sterilization group, followed by chemical sterilization, dry heat sterilization. In regards of the corrosive effect, the dry heat sterilization might be the best way to sterilize the dental fissure burs.

Dental Fissures ; Dental High-Speed Equipment ; Dental Instruments ; Steam ; Sterilization

OBJECTIVETo study the new hydrolysate of aconitine using HPLC-MS(n) and quantum chemistry calculation.

METHODThe HPLC method was applied in gradient elution program and the mass spectrometry was in positive ion mode. Geometries of the possible hydrolysates were optimized at DFT/6-31G(d) level.

RESULTThe new hydrolysate was found and its protonated molecularions was at m/z 482. The quantum chemistry calculation results show that the product of elimination reations at C8 and C15 got the lowest energy conformation. The compound at m/z 482 was decluced to be the hydrolysate of carbony at C15.

CONCLUSIONDelydration aconine was detected for the first time and the new hydrolysis pathways of aconitine in water were deduced.

Aconitine ; chemistry ; Chromatography, High Pressure Liquid ; Hydrolysis ; Mass Spectrometry ; Models, Molecular ; Molecular Conformation

OBJECTIVETo study the effect of Radix Scutellariae on the growth, metabolism of Porphyromonas endodontalis (P.e), as a preparation for studying the mechanism of Radix Scutellariae in treating pulp and periapical diseases.

METHODSP.e was chosen as the experimental bacteria. Radix Scutellariae was extracted by means of reflux with 80% ethanol. The value of MIC of Radix Scutellariae was measured by minute amount serial dilusion test, and the production of butyrate was measured by high liquid chromatograph(HPLC).

RESULTSRadix Scutellariae could inhibit the growth of P.e, of which the MIC was 100 mg/L. Following the increase in concentration of Radix Scutellariae, the amount of butyrate decreased to (3.527 +/- 0.009) mg/L, (3.048 +/- 0.005) mg/L, (2.490 +/- 0.011) mg/L, (2.209 +/- 0.016) mg/L, respectively (P < 0.05).

CONCLUSIONRadix Scutellariae could inhibit the growth and metabolism of P.e and might be an effective agent in treating pulp and periapical diseases.

Bacteroidaceae Infections ; microbiology ; Butyrates ; analysis ; Chromatography, High Pressure Liquid ; Dental Pulp ; microbiology ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Microbial Sensitivity Tests ; Porphyromonas endodontalis ; metabolism ; Scutellaria ; chemistry