AIM: To study the blocking effects of extracellular Cd 2+ on the inward rectifier potassium channel (IRK1) expressed in the Xenopus oocytes METHODS:Two-microelectrode voltage clamp (TEV) method was used RESULTS:Cd 2+ can concentration-, time- and voltage dependently block IRK1 instantaneous currents ( 1 5 ms after voltage applied ) when external Cd 2+ concentration is 0, 0 1, 0 15, 0 3, 0 9, 2 7 or 5 4 mmol/L with K + concentration fixed to 90 mmol/L Cd 2+ almost has no effect on the gating property and outward currents of IRK1 Cd 2+ can concentration-dependently increase the normalized conductance of IRK1 IRK1 can not permeate Cd 2+ because reverse potential did not change Three exponential fitting analyze indicates that time constant is not changed with the change in Cd 2+ concentration This shows that the inhibitory effects of Cd 2+ may be caused by surface potential or the blocking site of Cd 2+ is at the surface of the channel Because external Cd 2+ can not inhibit IRK1 macroscopic currents more powerfully when external Cd 2+ concentration is lower These mean that external Cd 2+ does not work through surface potential mechanism CONCLUSION: Cd 2+ is considered as one of the fast open channel blockers of IRK1 and its blocking site is at the surface of the channel

AIM:To study the blocking effects of extracellular Cd2+ on the inward rectifier potassium channel (IRK1) expressed in the Xenopus oocytes. METHODS：Two-microelectrode voltage clamp (TEV) method was used. RESULTS：Cd2+ can concentration-, time- and voltage dependently block IRK1 instantaneous currents ( 1.5 ms after voltage applied ) when external Cd2+ concentration is 0, 0.1, 0.15, 0.3, 0.9, 2.7 or 5.4 mmol/L with K+ concentration fixed to 90 mmol/L. Cd2+ almost has no effect on the gating property and outward currents of IRK1. Cd2+ can concentration-dependently increase the normalized conductance of IRK1. IRK1 can not permeate Cd2+ because reverse potential did not change. Three exponential fitting analyze indicates that time constant is not changed with the change in Cd2+ concentration. This shows that the inhibitory effects of Cd2+ may be caused by surface potential or the blocking site of Cd2+ is at the surface of the channel. Because external Cd2+ can not inhibit IRK1 macroscopic currents more powerfully when external Cd2+ concentration is lower. These mean that external Cd2+ does not work through surface potential mechanism.CONCLUSION:Cd2+ is considered as one of the fast open channel blockers of IRK1 and its blocking site is at the surface of the channel.

BACKGROUND:As a kind of adult stem cel s with low immunogenicity, mesenchymal stem cel s are able to differentiate into different cel lineages in the treatment of many diseases. Moreover, mesenchymal stem cel s have been extensively used in many fields such as stem cel transplantation, immune therapy, and tissue engineering. OBJECTIVE:To review the progress of homing mechanism and the strategies to promote mesenchymal stem cel homing, thus providing a theoretical basis for transplanting mesenchymal stem cel s safely and efficiently. METHODS:The CNKI and PubMed databases were retrieved by computer for articles regarding mesenchymal stem cel homing published from 2000 to 2016, including reviews, basic and clinical studies. The key words were“mesenchymal stem cel s, homing”in Chinese and English, respectively. Then 74 papers were suitable for final analysis. RESULTS AND CONCLUSION:Mesenchymal stem cel homing needs further research, especial y the molecular mechanism of cel mobilization. Therefore, basic research about mesenchymal stem cel s should be further developed, and a standardized homing system should be established in vitro. In addition, it is of great significance to study the in vivo effects of transplanted gene-transfected mesenchymal stem cel s.

Objective:To evaluate the effects of surface modified nano titanium-oxide on the mechanical properties of A-2186 silicone elastomers. Methods:Added surface modified nano titanium-oxide into A-2186 silicone elastomers with 0.0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% additions according to the ASTM standard. The mechanical properties of A-2186 silicone elastomer including the tensile strength, the broken elongation, the tear strength and the Shore-A hardness were tested separately. The section of samples were investigated by scanning electron microscope and energy spectrum analysis. Used statistics method to analyse the results. The results were analysed with software EPSS 13.0. Results:With the addition of nano titanium-oxide increasing, the tensile strength, the broken elongation and the tear strength of A-2186 silicone elastomers increased firstly, and then decreased. While the Shore-A hardness of A-2186 silicone elastomers increased gradually. When the addition of surface modified nano titanium-oxide reached to 2.0%, the nano titanium-oxide dispersed well in the base without agglomeration. Under such condition, the A-2186 silicone elastomer showed the best general mechanical properties:the tensile strength was (6.54?0.55) MPa, the broken elongation was 618.00?7.58(%), the tear strength was (16.64?0.52) kN/m and the Shore-A hardness was (31.00?0.79) U. Conclusion:The mechanical properties of A-2186 silicone elastomers are improved most greatly with 2.0% addition of surface modified nano titanium-oxide to the base of A-2186 silicone elastomers.

OBJECTIVE:To evaluate the quality of TCM decoction pieces in our hospital preliminarily and explore the solu-tions for the problem of the quality of decoction pieces purchased by the hospital. METHODS:In Jun. 2012,a system was estab-lished by our hospital,where the quality inspector was designated to daily inspect new batches of TCM decoction pieces such as ap-pearance provided by suppliers. The batches of TCM decoction piece samples inspected and those of unqualified products from Jun. 2012 to May 2014 were calculated. The reasons of unqualified products were analyzed and corresponding solutions were made. RE-SULTS&CONCLUSIONS:Over two years,a total of 94 671 batches of TCM decoction piece samples were inspected by our hos-pital,among which 737 were unqualified products predominantly because of mildew,damage by worms,greasing,containing for-eign substances and others. The solutions to such problems included interviewing the suppliers,returning or discontinuing the use of crude drugs and special focus on particular seasons and on the demand for key varieties. The unqualified products rate in the quality inspection reduced from 0.56%in Jun. 2012 to 0.34%in May 2014. Therefore,setting the post of drug quality inspector in the hos-pital can ensure the quality of TCM decoction piece purchased,however,it need to improve the inspection and acceptance of quali-ty inspection by sampling,scoring and using the new technology.

OBJECTIVE:To prepare and characterize celecoxib-loaded PLGA nanoparticles. METHODS:Emulsification-solvent evaporation method was adopted to prepare celecoxib-loaded PLGA nanoparticles. With encapsulation efficiency and particle size as the indexes,Plackett-Burman design was preferred to screen the formulation and variables which had a significant effect on the property of nanoparticles. And then Box-Behnken response surface method was used to further optimize selected variables including mass concentration of PLGA,ultrasonic power and ultrasonic time,followed by verification. Malvern particle size analyzer was used to determine the particle size distribution of nanoparticles and Zeta potential of nanoparticle by the optimal formulation technol-ogy,and transmission electron microscope was used to observe the morphology of the nanoparticles,and their drug release in vitro behavior and stability(25,5 ℃)were also observed. RESULTS:The optimal formulation and technology was as follows as PLGA mass concentration of 30.0%,ultrasonic power of 180 W and ultrasonic time of 8 min. For the prepared nanoparticles,encapsula-tion efficiency and particle size were (85.7 ± 4.1)% and (226.1 ± 36.1) nm (n=3) respectively;particle size distribution was (176.2±41.2)nm,polydispersity index was 0.211±0.021,and Zeta potential was(-37.3±1.6)mV. Under the electron micro-scope,the nanoparticles were homogeneous in particle size and distributed spheroidally,with 24 h accumulative release of 52.4%. They were stable within 3 months at 5℃. CONCLUSIONS:Celecoxib-loaded PLGA nanoparticles have been prepared successfully.

Objective To evaluate the utility of CD4+ TCR tetramers‐based flow cytometric analysis and cell climbing slice assay in detecting antigen‐specific CD14+ monocytes in the blood of tuberculosis (TB) patients .Methods CD4+ TCR tetramers were used to detect tetramer‐positive CD14+ monocytes in the peripheral blood (PBL ) samples of inpatients with advanced pulmonary TB (PTB) by flow cytometric analysis .The PBL samples obtained from non‐TB patients and umbilical cords were used as controls .These tetramers were also used to examine tetramer‐bound CD14+ monocytes and Mycobacterium tuberculosis (MTB) antigen‐specific and tetramer‐bound cells by cell climbing slice in situ staining .Results The median percentage of tetramer‐bound CD14+ monocytes in PBL samples from PTB patients ,non‐TB patients and umbilical cords were 1 .32% , 0 .50% and 0 .26% respectively by using CD4+ Vα21‐J39/Vβ29‐D1‐J2 tetramer , while the medians were 1 .05% , 0 .49% and 0 .19% respectively by using CD4+ Vα21‐J39/Vβ29‐D2‐J2 tetramer . The percentage of tetramer‐bound CD14+ monocytes in PTB patients group was significantly higher than the other two control groups .In cell climbing slice in situ staining ,tetramer‐bound CD14+ monocytes ,and MTB antigen‐specific and tetramer‐bound cells were positive in PTB tissue compared with negative in control tissues . Conclusions CD4+ TCR tetramers‐based flow cytometric analysis and cell climbing slice assay could be used to sensitively detect M TB antigen‐specific CD14+ monocytes in the blood of TB patients ,and more accurately evaluate the changing profile and clinical significance of these cells in TB patients .

Objective:To explore the differences of CBCT image gray value of commonly used dental materials.Methods:CBCT was used to scan 36 kinds of commonly dental material blocks,the tomographic image gray value was measured by Mimics software.Re-sults:CBCT image gray values of the materials were obtained.There were differences of the gray values of the materials not only among the different types,but also among the different varieties of the same materials.Conclusion:The discipline of CBCT image gray value differences of commonly used dental materials provided an objective basis for the establishment of 3D digital model including dental ma-terials.

Objective To investigate the prognosis of patients with nasal NK/T cell lymphoma receiving different treatment modalities. Methods From 1990 to 2004, 85 patients with stage ⅠE and ⅡE primary nasal NK/T cell lymphomas were retrospectively studied. Twenty patients received chemotherapy of CHOP regimen alone, 11 patients received radiotherapy only, 6 patients received radiotherapy followed by more than 2 cycles of chemotherapy, and 48 patients received more than 2 cycles of chemotherapy followed by radiotherapy. Survival analysis was performed by the Kaplan-Meier method, the difference between groups was evaluated by the Log-rank test, and the Cox regression model was used for multivariate analysis. Results The 5-year overall survival rate (OS) was 40%. The 5-year OS was 57% and 28% for limited stage ⅠE and extended stage ⅠE(X2 =8. 87, P =0. 003), and 23% for stage ⅡE, which was similar to extended stage ⅠE (X2 =0. 19, P-0. 664). The 5-year OS was 13%, 54% and 47% for chemotherapy alone, radiotherapy followed with or without chemotherapy, and chemotherapy followed by radiotherapy, respectively. The last two groups had better OS than chemotherapy alone (P = 0. 030 and 0.049). The 5-year OS was 58% and 12% for patients achieving complete response (CR) and uncomplete response (X2 = 30.68, P = 0. 000).The CR rate was 56% and 86% for radiotherapy of ≤50 Gy and >50 Gy (X2 =6.11, P=0. 013). The corresponding 5-year relapse-free survival rate was 89% and 84% (X2 =0.36, P=0.551). Of 68 patients receiving initial chemotherapy, the CR rate of those who received ≤2, 3-4 and ≥5 cycles was 0, 20%and 3 3 % , respectively (X2 = 7.65 , P = 0. 022) . For 5 0 patients who received ≥ 3 cycles of initial chemotherapy and 17 patients who received initial radiotherapy of ≥40 Gy, the CR rate was 28% and 88%(χ2= 18. 75, P= 0. 000). In patients with pathological nodular and ulcer type, the CR rates with radiotherapy were higher than with chemotherapy (100%: 38%, χ2 = 7.92, P = 0. 005; and 100%: 11%,χ2 = 14.40, P = 0. 000). Multivariate analysis showed that stage and recent effect were the independent prognostic factors. Conclusions The initial radiotherapy with 50 Gy is appropriate for early stage nasal NK/T cell lymphomas. Combined chemotherapy could be used for extended stage ⅠE and ⅡE, but the outcome of CHOP regimen is poor.

BACKGROUND:Bone cement solidification can improve the stability, strength and mechanical support of fractured vertebrae. However, there are few studies on the effect of bone cement dispersion within the fracture line on percutaneous vertebroplasty. OBJECTIVE:To analyze the effect of bone cement dispersion within the fracture line of thoracolumbar osteoporotic vertebral compression fractures on percutaneous vertebroplasty. METHODS:Totaly 90 patients with thoracolumbar osteoporotic vertebral compression fractures were enroled, 53-80 years old, including 42 males and 48 females. Al these patients underwent percutaneous vertebroplasty with bone cement injection, and divided into two groups according to bone cement dispersion conditions: study group with good bone cement dispersion (n=60) and control group with poor bone cement dispersion (n=30). Visual analogue scale scores, Oswestry dysfunction index, Cobb's angle and adverse reactions were recordedbefore and after treatment. RESULTS AND CONCLUSION:There were no differences in the visual analogue scale score and Oswestry dysfunction index between the two groups before treatment (P > 0.05). The visual analogue scale scores were significantly lower in the study group than the control group at 3 days after treatment and at the last folow-up (P < 0.05); the Oswestry dysfunction index and Cobb's angle were also lower in the study group than the control group at 3 days after treatment (P < 0.05). However, no difference was found in the Oswestry dysfunction index, Cobb's angle and bone cement leakage between the two groups at the last folow-up. These findings indicate that the percutaneous vertebroplasty show better effects on pain relief in patients with good bone cement dispersion that those with poor bone cement dispersion, and the vertebral stability is better as wel as the short-term effect is more obvious.