A thermostable DNA ligase gene was identified, and the biochemical and enzymatic properties of the ligase were characterized from JP2 strain which was enriched from geothermally active sites in Papua New Guinea. The nucleotide and amino acid sequences showed much high identities compared with that of archeabacterium species Sulfolobus solfataricus and Sulfolobus shibatae,especially in the six conserved motif sequences, which are known to be closely related to the key function of ligase. Recombinant JP2 ligase showed high activity in nick-joining reaction. It was the most active when Mn2+ present as divalent metal cofactor rather than Mg2+ and Ca2+ etc.. Assay of thermostability over a range of temperatures showed that at 50～80℃ the enzyme displayed relative high activity. Further thermostability experiment indicated that the activity of JP2 ligase could last for a long time at 80℃ and 85℃,however, at 90℃ and 95℃, it became unstable quickly. An investigation on the acquired thermotolerance of recombinant JP2 ligase was done by applying a chaperonin known as TF55 in thermophile on JP2 ligase reaction. Result showed that TF55 could not help in improving thermostability of ligase at 85℃. The possible reason might be that at 85℃ in vitro, the chaperonin itself was denatured.

The tissue chip is a special tissue section,which has several tens to thousands mini tissues of regular arrangement on the one glass slide.According to the deficiencies in experimental teaching section of morphology at present,the author introduced the characteristics and values of the tissue chip and explored its application prospect in experimental teaching of morphology.

Objective: To explore the quality of life of children with behavior problems. Method: A sample of 2087 children were administered Conners Scale and Inventory of Subjective of Life Quality, then we compared the quality of life of normal children with that of children with behavior problems. Result: Children with behavior problems had poorer life quality than normal children. Stepwise regression revealed that seven variables offacted subjective satisfaction of the children, including academic achievement, behavior problems, economic condition of the family, father's personality, age, parental coping style for poor behavior, single child family. Conclusion: Behavior problems of children are also problems of the family.

BACKGROUND: The effect of Chinese traditional medicine 3'-meisoindigo as well as indimbin derivatives on normal immunocytes is less reported while it is used for antitumor.OBJECTIVE: To investigate the effect of 3'-meisoindigo on the proliferation of the splenocytes and thymocytes of C56BL/6 mouse.DESIGN, TIME AND SETTING: The randomized cytopathology observation was performed between August 2007 and January 2008 at Zhujiang Hospital of Southern Medical University, Guangzhou, Guangdong Province, China.MATERIALS: C57BL/6 mice, clean, male, 6-8 weeks old, weighing (20±2) g.METHODS: The thymus gland and the spleen of C57BL/6 mice were ground to get the single-cell suspension and cells were treated by 5, 10, 15, 20 and 25 μ mol/L 3'-meisoindigo,respectively. Cells without any drug treatment were used as blank control and cells treated by concanavalin A were used as positive control.MAIN OUTCOME MEASURES: Proliferation of splenocytes and thymocytes detected using MTT method; IL-12 activity in culture supematant detected using ELISA method; the cell cycle, apoptosis rate, cell death rate and intracellular reactive oxygen species level detected using flow cytometry; the mRNA level of bcl-2 and cdk2 detected using reverse transcription-polymerase chain reaction; the expression rate of Bcl-2, CDK2 and Bax detected using fluorescence microscope.RESULTS: After treating for 24 hours, 15, 20 and 25 μ mol/L 3'-meisoindigo can significantly inhibit the proliferation of thymocytes and splenocytes (P < 0.05) and the inhibition was dose-dependent and time-dependent. Cells resumed proliferation after removing the 3'-meisoindigo, although they had been treated by 25 μ mol/L 3'-meisoindigo for 72 hours. The secretion of IL-12 was markedly reduced in all 3'-meisoindigo groups versus control groups at each time point (P < 0.05). 15 μ mol/L 3'-meisoindigo could decrease the mRNA expression level of apoptosis-related protein bcl-2 and cyclin cdk2 gene, decrease the expression level of BCL-2 protein and CDK protein, increase Bax expression level, decrease Bcl-2/Bax ratio markedly and started apoptosis.15 μ mol/L 3'-meisoindigo arrested cells in the G2/M stage of the thymocytes and splenocytes, and intracellular reactive oxygen species level elevated dose-dependently and time-dependently.CONCLUSION: In certain concentration range, 3'-meisoindigo can reversibly inhibit the proliferation of thymocytes and splenocytes of C57BL/6 mouse and can inhibit IL-12 secretion in parallel, and start apoptosis.

OBJECTIVE:To investigate the effects of calcitriol on related indicators in patients with chronic renal failure (CRF). METHODS:114 patients with CRF were randomly divided into observation group(57 cases)and control group(57 cas-es). Control group was given high-quality low-protein and low phosphorus diet,if necessary,phosphate binders,Calcium D3 tablet and other conventional treatment;observation group was additionally given 0.25 μg Calcitriol soft capsule,once a day. The treat-ment course for both groups was 8 weeks. Serum levels of inflammatory factors,alkaline phosphatase,hemoglobin,erythrocyte, serum creatinine and urea nitrogen levels and adverse reactions in 2 groups before and after treatment were observed. RESULTS:Before treatment,there were no significant differences in the serum levels of inflammatory factors,alkaline phosphatase,hemoglobin, erythrocyte,senum creatininine and ureanitrogen between 2 groups(P>0.05). After treatment,serum inflammatory factors,alkaline phosphatase,serum creatinine and urea nitrogen levels in 2 groups were significantly shorter than before,and observation group was lower than control group,the differences were statistically significant (P<0.05);there were no significant differences in the hemoglobin and erythrocyte levels before and after treatment between 2 groups(P>0.05). And there was no obvious adverse reac-tions between 2 groups during treatment. CONCLUSIONS:Based on the conventional treatment,calcitriol can reduce the levels of serum inflammatory factors and improve micro-inflammatory state and renal function in patients with CRF.

Objective To explore an effective evaluation method for students' self-and peer-assess-ment. Methods The students of 6 groups participating in extracurricular teaching activities were selected as research subject. Traditional method (final score = mean score of group/2 + teacher's score/2) and mean difference method [final score=teacher's score-(mean difference of group-mean difference of all groups)] were used to calculate final score of each group, and effect of two methods were compared. Results Scores of most groups were higher than the teacher's scores, and high scores were given by group 3 in self- and peer-assessment. The final score of all groups were higher than teacher's scores in traditional method. Compared with teacher's scores, final scores increased significantly in group 1, 4, 5 below mean difference, final score decreased significantly in group 2, 3 above mean difference, and final score did not differ in group 6 equal to mean difference in mean difference method. Conclusion The mean difference method can reflect the effect of student's self- and peer-assessment, and guide student to make objective and accurate evaluation. It is a more reasonable and scientific evaluation method for self-and peer-assessment.

Objective To evaluate the guidance value of endoscopic ultrasonography (EUS) and CT scan in preoperative clinical staging for diagnosis and treatment of esophageal cancer .Methods 68 patients with esophageal cancer were randomly divided into EUS group and CT group using a random numbers table(34 cases in each group) .Patients in EUS group were examined by EUS , patients in CT group were examined by CT scan ,and staged according to the TNM (2003) staging system ,and were compared with surgical pathologic findings .Results The accuracy rates of T staging by EUS were 0(0/2) for Tis ,75 .0% (3/4) for T1 ,75 .0% (6/8) for T2 ,86 .7% (13/15) for T3 ,80 .0% (4/5) for T4 ,and the totle accuracy rate was 76 .5% (26/34) for T ;those of N staging were 71 .4% (5/7) for N0 ,75 .0% (9/12) for N1 ,0(0/11) for N2 ,0(0/4) for N3 ,and the totle accuracy rate was 41 .2% (14/34) for N .The accuracy rate of T staging by CT scan were 0(0/1) for Tis ,33 .3% (2/6) for T1 ,28 .6% (2/7) for T2 ,78 .6% (11/14) for T3 ,83 .3% (5/6) for T4 and the totle accuracy rate was 58 .8% (20/34) for T ,the difference was statistically significant com-pared with the EUS group(P<0 .05);those of N staging were 77 .8% (7/9) for N0 ,76 .9% (10/13) for N1 ,66 .7% (4/6) for N2 , 50 .0% (3/6) for N3 and the totle accuracy rate was 70 .6% (24/34) for N ,the difference was statistically significant compared with the EUS group (P<0 .05) .Conclusion The accuracy rate of EUS are higher for diagnosis in esophageal cancer and preoperative T staging .The accuracy rate of CT scan are higher for the preoperative N staging .EUS combined with CT scan has great significance for choosing ideal therapy plan for esophageal cancer ,and for estimating prognosis of esophageal cancer .

Objective: To investigate the effect of intracellular free Ca 2+ concentration ([Ca 2+ ] i ) on injury following transient Mg 2+ free treatment in vitro in developing cortical neurons. Methods: Embryo cortical neurons of rats cultured for 6 d and 17 d were directly exposed to Mg 2+ free media, or pretreated with NMDA receptor antagonists or calcium channel antagonist before being exposed to Mg 2+ free media. MTT assay was used to study the injury of neurons. [Ca 2+ ] i were measured using fluo 3, a fluorescent calcium sensitive dye and laser scanning confocal microscope, and calculated by the fluorescent intensity. Results:Compared with control, MTT conversion rates decreased after transient (3 h) Mg 2+ free treatment in neurons cultured for 6 d and 17 d in vitro, (59.1?6.87)% and (51.2?5.90)%, respectively. In neurons pre and co treated with 10 ?mol?L -1 MK 801, 50 ?mol?L -1 AP 5 and 10 ?mol?L -1 nifedipine, MTT conversion rates were higher than those of neurons with only Mg 2+ free treatment. Peak values of [Ca 2+ ] i in neurons cultured for 6 d and 17 d were 2.4?0.23 and 3.2?0.32, respectively Peak value of neurons 17 d in vitro was significantly higher than that of neurons 6 d in vitro (P

Objective:To analyze the dental and mandibular asymmetry of adults with Class Ⅱ subdivision malocclusion.Methods:The jaw bones of 30 adults with Class Ⅱ subdivision malocclusion(case group)and 30 with normal-occlusion(control group)were scanned by CBCT.Linear and angular comparison was conducted between the two groups.Results:Dental midline deviation was ob-served in case group,mostly in mandibular arch (60%).The development of Class Ⅱ molar relationship correlated mainly to distally positioned mandibular molar on Class Ⅱ side.Conclusion:In the adults with Class Ⅱ subdvision malocclusion odontogenic asymme-try is the major factor,bony asymmetry is the miner.

Objective To investigate the role of basophils in the imbalance of Th 1/Th2 response in mouse models of collagen-induced arthritis(CIA).Methods 4-6-weeks old C57/BL6 mice were immunized with collagen at multiple points on the back and foot twice (0 and 3 weeks) to establish a mouse model of collagen-induced arthritis.Blood samples were collected before the first immunization and 1, 3, 6 and 9 weeks after immunization , and cells from lymph nodes were collected.Flow cytometry and ELISA were employed to detect the levels of basophils and IL-4, and the joint swelling was scored.Results Mouse model of CIA was successful established .The ratio of IL-4/IFN-γof the CIA group was significantly lower than that in the mice before CIA modeling and the control group , indicating a Th2-dominant response .At the same time, the peripheral basophils counting and percentage of IL-4 positive basophils of the CIA group were significantly higher than those of the control group .While, the IL-4/IFN-γratio of the CIA group was significantly higher than that of the control group , indicating a Th1-dominant response .The peripheral basophils counting of the CIA group was slightly lower than that of the control group .Conclusion Basophils may participate in the development of CIA in mouse models through affecting the imbalance of Th 1/Th2 response.