Objective To study the sub chronic toxicity of silver nanoparticles on medaka.Methods Adult fish were divided into silve nenopartides and control group.Animals were collected on 14 days after exposure, and some toxicological endpoints such as death rate, tissue distributed of silver irons, oxidative stress and histopathological damage were measured.Results There were significant difference in death rate of medaka treated with silver nanoparticles and control group.Compared with the control group, the content of silver in gill, intestine and liver of medaka treated with silver nanoparticles were increased significantly.Compared with control group, the activity of LDH in liver and SOD in liver and gill were significantly decreased(P<0.01).The content of MDA in liver of medaka treated with silver nanoparticles was significantly increased(P<0.01).The liver and gill of mekada treated with silver nanoparticles were damaged, compared with control group.Conclusion Nano silver has a certain subchronic toxicity to aquatic life.

Objective To study the early diagnosis and management of the patients with acute respiratory distress syndrome (ARDS) caused by cytomegalovirus (CMV) pneumonia after liver transplantation.Methods The clinical data of 8 patients with ARDS caused by CMV pneumonia after liver transplantation in our hospital from April 2001 to May 2004 was retrospectively analyzed. All cases were treated with intravenous infusion of gancyclovir, reduced dosage of cyclosporine A or tacrolimus to 1/3~1/2 of baseline and withdrawal of MMF and prednisone. The patients were subjected to breathing machine assist ventilation and nutrition supply.Results Five patients recovered and 3 died. No one developed acute rejection. Conclusions The key of early diagnosis lies in combining chest X-ray or CT scan with clinical presentation. Administration with anti-viral drugs, adjustment of immunosuppressive agents, management with breathing machine assist ventilation and effective nutrition supply are important for the treatment of patients with ARDS caused by CMV pneumonia after liver transplantation.

Objective To determine the optimal cut-off value of critical-care pain observation tool (CPOT) in assessing degree of pain in patients undergone craniotomy, and to determine the sensitivity and specificity of CPOT with this cut-off value. Methods A prospective observational study was conducted in Beijing Tiantan Hospital. A total of 118 patients admitted to intensive care unit (ICU) after craniotomy was consecutively enrolled during August 2014 to August 2015. CPOT and visual analogue scale (VAS) were used to assess the pain before, during and 20 minutes after the removal of central venous catheters, and the difference was compared between two scores at three time points. Receiver operating characteristic (ROC) curve was used to determine the optimal cut-off values for evaluation of the sensitivity and specificity of CPOT. Patients' complaint of pain was considered the gold-standard. Results CPOT values (inter-quartile range) before, during and after the procedure were 0 (0-3), 0 (0-6) and 0 (0-2), respectively; while VAS values were 4 (1, 6), 3 (1, 6) and 4 (1, 6), respectively. CPOT value during the procedure was significantly higher than CPOT values before and after the procedure (both P < 0.01). When the optimal cut-off value of CPOT was 1, CPOT showed the highest Youden index before, during and after the procedure (1.183, 1.515, and 1.438, respectively), and showed high specificity (all 100%) and low sensitivity (18.3% and 43.8%, respectively) when assessing the pain before and after the removal of the catheter. The sensitivity and the specificity were high when assessing the pain during the procedure, the sensitivity was 69.4%, and the specificity was 82.1%. When the optimal cut-off value of VAS was 2 before and during the procedure, and was 4 after the procedure, VAS showed the highest Youden index, 1.568, 1.452, and 1.509, respectively. VAS demonstrated high sensitivity and specificity before, during and after the procedure (sensitivity was 97.2%, 95.2% and 75.0%, respectively; specificity was 59.6%, 50.0% and 75.9%, respectively). The area under ROC curve (AUC) of CPOT before, during and after the procedure were 0.592 [95% confidence interval (95%CI) = 0.490-0.693], 0.778 (95%CI= 0.693-0.863) and 0.719 (95%CI = 0.627-0.811), respectively; the AUC of VAS before, during and after the procedure were 0.846 (95%CI = 0.771-0.920), 0.767 (95%CI = 0.681-0.854) and 0.838 (95%CI = 0.767-0.909), respectively. The AUC of VAS before and after the procedure was significantly higher than the AUC of CPOT (P < 0.001 and P = 0.006), while there was no significant difference between the AUC of VAS and CPOT during the procedure (P = 0.826). Conclusion CPOT can be used to assess the pain during painful procedure, and it shows high accuracy, but with poor evaluation effect on pain in rest.

Objective To study the effect of Licofelone,a novel non-steroid anti-inflammatory drug,on the expression of Fractalkine induced by interleukin-18(IL-18) in mesangial cells.Methods Rat mesangial cells were cultured and divided into IL-18 stimulated group,Licofelone-treated group and normal control group.The cells in IL-18 stimulated group were stimulated by 10 ?g/L IL-18 for 24 h.In Licofelone-treated group,ahead of exposure of IL-18 for 24 h,cells were treated with Licofelone in the doses of 10,50 and 100 ?mol/L for 30 min.Additionally,the mesangial cells without treatment of IL-18 and Licofelone were used as normal control group.Reverse transcription-polymerase chain reaction(RT-PCR) was used to measure the level of Fractalkine mRNA.The expressions of Fractalkine protein in every group were detected with enzyme linked immunosorbent assay (ELISA).Results In normal control group,the expression level of Fractalkine mRNA was 179.0?21.0.After exposure of IL-18 for 24 h,the level of Fractalkine mRNA was 1 220.1?185.7,which was higher than that in normal control group (t=9.646 P

In order to study the character of periodontal ligament cells (PDLCs) attaching on commercially pure titanium (cpTi) by morphology and metrology on the early stage (24 h), 1 x 10(5)/ml PDLCs in 2 ml culture medium were seeded on cpTi discs fixed in 24-well culture plates. Morphology of cell attachment was observed by contrast phase microscope, scanning electron microscope (SEM) and fluroscence microscopy. Cell adhesion was analyzed by MTT at 0.5, 1, 2, 4 h respectively. PDLCs could attach and spread on cpTi discs. SEM showed that PDLCs had pseudopod-like protuberance. PDLCs showed different attaching phases and reached saturation in cell number at 2 h. It was concluded that PDLCs had good biocompatibility with cpTi, and showed a regular and dynamic pattern in the process of attaching to cpTi.
Biocompatible Materials/pharmacology ; Cell Adhesion ; Cell-Matrix Junctions ; Cells, Cultured ; *Dental Implants ; Periodontal Ligament/*cytology ; Surface Properties ; Time Factors ; Titanium/*pharmacology

Total caudate lobectomy via anterior hepatic transection is still a new technique to resect the tumor in the caudate lobe,which is mastered only by few surgeons.The procedure was successfully performed on a 21-year old patient with focal nodular hyperplasia in caudate lobe.The right and left lobes were first mobilized,then the short hepatic veins were dissected to detach the caudate lobe from the retrohepatic vena cava.Then the liver was split anteriorly and the partial middle lobe was resected.With this process,the tumor was in the sight and we dissected it from the liver parenchyma.The inflow blood was occluded 3 times with a period of 29,27 and 27 minutes,respectively,with an interval of 5 minutes.The total blood loss during operation was 1000 ml.The patient recovered quickly without any complications.The technique for caudate lobectomy via anterior hepatic transection can improve the success rate and safety of caudate lobectomy and deserve clinical consideration.

BACKGROUND:The hyperpoladzation-activated cyclic nucleotide-gated cation channel (HCN) gene is not increase the risk of induced cardiac arrhythmia,and can accept the modulation function of autonomic nervous system.Therefore,it is the first candidate gene for biological pacemakers.OBJECTIVE:To construct recombinant adenovirus vector containing human HCN4 gene and evaluate its transfection efficency in rat bone marrow mesenchymal stem cells (MSCs).DESIGN,TIME AND SETTING:The in vitro cytology-gene experiment was performed at the Lin Bai-xin Experimental Center,Second Hospital of Sun Yat-sen University from February to September 2008.MATERIALS:Ten SD rats were supplied by the experimental animal center of Sun Yat-sen University.Rlasmid pcDNA3.1-HCN4 containing target gene human HCN4,human embryo kidney 293 cells and Escherichia coll DH5α were preserved by our experimental center;Shuttle plasmid pShuttle-CMV containing green fluorescent protein gene and adenoviral backbone plasmid pAdxsi were bought from SinoGenoMax Co.,Ltd.METHODS:HCN4 cDNA segment was liberated from the cloning vector of pcDNA3.1-HCN4 via Hind Ⅲ+Xba Ⅰ,and subcloned into pShuttle-CMV,which was digested by I-Ceu Ⅰ +I-Sce Ⅰ double enzyme and subcloned into adenoviral plasmid to form recombinant adenovirus plasmid.Recombinant adenovirus plasmid was transfected into 293 cell lines by liposome,and the recombinant adenovirus AdHCN4 was packaged and transfected into rat MSCs.MAIN OUTCOME MEASURES:The identification of recombinant adenovirus plasmid vector,identification of recombinant adenovirus and its titration test;the transfection efficiency of recombinant adenovirus.RESULTS:Cloned sequence about 3.6kbp was obtained by Hind Ⅲ+Xho Ⅰ digestion after HCN4 cDNA segment was cloned into pShuttle-CMV.DNA sequencing results indicated that the clone location was correct.Recombinant adenovirus plasmid was cut into seven fragments while empty vector gained only six fragments after digested by Xho Ⅰ.The recombinant adenovirus was pathogenic to 293 cells after recombinant adenovirus plasmid was packaged in it.HCN4 cDNA (657bp) was amplified by PCR with virus titer of 2.5×10~(11) PFU/mL after transfected 293 cells with supematant.The efficiency of recombinant adenovirus infecting rat MSCs was about 90% when multiplicity of infection was 800.Rat MSCs expressed green fluorescence after transfection.CONCLUSION:The adenovirus vector with human HCN4 cDNA was established successfully,which can effectively transfect rat MSCs.

Objective To develop neural stem cells(NSCs) which can stably express exogenous brain-derived neurotrophic factor(BDNF) in vitro. Methods NSCs from the subependymal zone of embry-onic day 14.5(E14.5) rat brain were purified by limiting dilution assay and then infected with supernatant of recombinant retrovirus pLXSN-BDNF and retrovirus pLXSN. The original copy numbers of exogenous gene templates from three groups NSCs(pLXSN-BDNF viral infection group, pLXSN viral infection group, control group) were detected by fluorescent quantitative PCR(FQ-PCR). ELISA assay was used for determining the protein contents of BDNF of supernatant from three groups NSCs for six days continually after seeded in 24-well plates in the same cell density. Results NSCs were purified successfully by limiting dilution assay.The original copy numbers of exogenous BDNF gene templates from pLXSN-BDNF viral infection group by FQ-PCR were (19.57±0.65) × 10~3 copies/μl, higher than those of another two groups(P < 0.05). The protein contents of BDNF of supernatant from NSCs of pLXSN-BDNF viral infection group was highest among three groups and compared with another two groups had statistical significance (P <0.05) . Conclusion The purified NSCs can be transduced exogenous BDNF successfully with supematant of recombinant retrovir-us pLXSN-BDNF which provide experimental evidences and laying foundations for further research of retinal transplantation and quantization investigation of gene therapy for optic nerve injury.

Age-related macular degeneration ( AMD ) is a kind of age-related blinding degenerative fundus lesions, totally about 30 million patients suffering from AMD all over the world, with about 500 000 people blind for it yearly. As the development of economy and the aging of the population intensified, incidence of AMD indicates a trend of rising year by year, being the third major cause of blindness in our country. At present, the pathogenesis of AMD is not fully clear, as reported it may be related to oxidative stress, inflammatory immune response, VEGF and genetic manipulation. Clinical treatments mainly include photodynamic therapy, drug therapy, radiation therapy, laser photocoagulaory operation, the pupil warm treatments, Chinese medicine and intravitreous injection VEGF antagonists such as Ranibizumab, Conbercept and so on. ln this issue, we mainly expound on the progress in the epidemiological studies of AMD, especially elaborate the progress made on genetic manipulation in recent years.

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.