Objective To investigate the effect of a kind of tissue engineered bone implants on healing of segmental bone defects. Methods A 15 mm bone defect experimental model at the right radius of New Zealand white rabbit was made. 24 animals of this model were divided into three groups at random. PLGA scaffords loaded with 5 mg BMP and about 1?106 BMSCs were implanted in Group 1(n=10); PLGA scaffords loaded with 2.5 mg BMP and about 1?106 BMSCs were implanted in Group 2(n=7); PLGA scaffords loaded with 1 mg BMP and about 1?106 BMSCs were implanted in Group 3(n=7). The osteogenesis at the defect area was observed by regular roentgenography and X-ray analysis, histological changes at the bone defects at 4th, 8th, 12th weeks after operation were studied and the new bone formation was measured by image analysis. Biomechanical analysis was done 12 weeks after operation. Results A large quantity of callus was found in all the 3 groups 4 weeks after repair. At the 12th week, the complete bone healing rate was 7/8, 3/5, 3/5, respectively in Group 1, 2 and 3. Group 1 had the largest quantity of new bone measured by histopathological study and X-ray analysis, and at the 12th week, the medullary cavity in this group became united. The compress stiffness, torsion stiffness and the maximal load in Group 1 were better than those in other groups. Conclusion The tissue engineered bone contructed by PLGA scaffords that are loaded with 5 mg BMP and BMSCs is capable of repairing segmental bone defects.

Objective To investigate different methods in parathyroid adenoma tissue storage and to provide theoretical support for standardized construction of parathyroid adenoma tissue data.Methods 22 samples of sporadic parathyroid adenoma in Beijing Union Hospital from Aug.2010 to Nov.2011 were collected.All cases obtained pathological diagnosis,among which 11 were kept in frozen nitrogen (group A)and the rest in RNAlater(group B).The ratio of OD 260/280 was measured by ultraviolet spectrophotometer.The integrity of RNA was examined by gel electrophoresis.The expression of β-actin was measured by Realtime-PCR technique.Results RNAlater group had no advantage than frozen nitrogen group in terms of the purity,concentration,and integrity of the extracted RNA(P ＞0.05),but had a higher expression level of the β-actin(P ＜0.05).Conclusion The method of RNAlater has no significant advantages compared with frozen nitrogen in terms of RNA prevention and RNA degradation,but is more effective in longer storage of samples.

Three bactreiophages of Pseudomonas aeruginosa were isolated from sewage and named as PaP1, PaP2 and PaP3. All belong to double-strand DNA phages, their genome is about 47kb, 34kb and 24kb respectively. The titre (pfu/mL) of three phages is respectively 109, 1011 and 1011, PaP1 is lytic phage, both PaP2 and PaP3 are lysogenic. Under electron microscope, All show icosahedral heads with diameter of 70nm, 55nm and 65nm respectively. PaPl belongs taxonomically to Myoviridae, and both of PaP2 and PaP3 belong to Pedoviridae. The phage-re-sistance and substitution phenomenon of the resistant flora for the sensitive were observed, and the mutation frequence of Pseudomonas aeruginosa resistant to the phage is about 1.4 ? 10-7 ~ 7.9 ?10-7 determined by end-point -titer method.

BACKGROUND:The poly-lactic acid and its ramifications have many advantages, such as eligible biocompatibility,nontoxicity of degradation product, easy procession and suitable intensity. Thus, they have been widely used in bone tissue engineering.OBJECTIVE: To study the cellular biocompatibility and in vitro adhesion of poly(lactic-co-glycolic acid) (PLGA) scaffold and bone marrow stromal stem cells (BMSCs) so as to provide a basis for preparation a PLGA scaffold that can load many cytokines.DESIGN: Contrast observation.SETTING: Department of Orthopaedics and Traumatology in Nanfang Hospital of Southern Medical University.MATERIALS: The experiment was carried out in Key Laboratory of Tissue Construction and Detection of Guangdong Province from September 2004 to June 2005. One New Zealand healthy male rabbit (2 months old, 1.5-2.0 kg weight)was adopted in this study. Experimental materials: PLGA scaffold was obtained from Institute of Polymer Science in Sun Yat-sen University); beta-tricalcium phosphate (β-TCP) was supplied by AO Company (Switzerland).METHODS: Bone marrow was aspirated from the New Zealand rabbit. Mononuclear cells were harvested using whole bone marrow culturing, then were induced and amplified in the conditional culture medium. BMSCs were inoculated onto the PLGA and β-TCP at a concentration of 1 ×109 L-1, while those in the medium without materials were taken as blank control group. The development of implanted cells and the adhesion between cells and materials were observed with phase contrast microscope and scanning electron microscope. The proliferation and cycle of cells were tested with MTT method and flow cytometry.MATN OUTCOME MEASURES: ①Phase contrast microscope was used to observe the development of cells and the adherence between cells and materials at a fixed time every day. ②Cellular development on days 1, 3, 6 was observed by scanning electron microscope. ③Cellular proliferation was detected by MTT method. ④Alkaline phosphatase (ALP) activity was determined by chemical colorimetry.⑤Flow cytometer test: The effects of PLGA and β-TCP on the cellular cycle, content of DNA and polyploid levels of BMSCs were investigated. The DNA index of the candidate cells was also calculated.RESULTS: ①Phase contrast microscope observation: In the blank control group, cells culture for 7-10 days presented a larger number of shuttle-shaped, and no contact inhibition effect was observed. The time of cells beginning adherence in PLGA group was obviously later than that in β-TCP group. Cells began to develop on the circumambience and surface of the materials, with the prolonging of culture time. Most of the cells were multangular. The cells in both PLGA and β-TCP groups were similar to those in control group in items of cellular development and shape. ②Scanning electron microscope observation: On the seventh day of culture, the cells of control group remained a monolayer and amalgamated to be a patch with multangular-shaped ones increasing. There were substances in granule shape on the surface of the cells and micro-silk links between cells. In PLGA group, the cells After 7 days' cultivation proliferated sharply, and the compressed-shaped ones were inosculated to be a patch through integrations among cells, resulting in a large number of matrixes. While in β-TCP group, the number of cells increased from the 7th day. The cells were combined together to be a monolayer and moved to pores with matrixes creating out of cells.③Cellular proliferation: The number of the cells in each group all increased to some extents. However, there was no significant difference between the PLGA group and the control group, as well as the PLGA group and the β-TCP group (P ＞ 0.05).④ALP activity: The　content of ALP in all the groups enhanced without exception, while the activities between the PLGA group and the Both control group, as well as the PLGA group and the β-TCP group had no significant difference (P ＞ 0.05).⑤Cellular cycle:Both PLGA and β-TCP had slight effects on cellular cycle of BMSCs. The cells in each group were all normal diploid,and no heteroploid cells were discovered.CONCLUSION: This type of PLGA scaffold possesses good cellular biocompatibility, and can be used as a carrier of many factors in bone tissue engineering.

Objective To study the influence of Salviae Miltiorrhizae Radix et Rhizome (SMR) and Carthami Flos (CF) before and after compatibility on activitis of cytochrome P 1A2 (CYP1A2),cytochrome P2E1 (CYP2E1),and cytochrome P3A4 (CYP3A4) from rat liver microsomes.Methods Using caffeine,chlorzoxazone,and midazolam as the probe drugs ofCYP1A2,CYP2E1,and CYP3A4,the SD rats were randomized divided into four groups:control group,SMR (1.2 g crude drug/kg) group,CF (0.4 g crude drug/kg) group,and SMR (1.2 g crude drug/kg) + CF (0.4 g crude drug/kg) group.According to the above dose,rats were ig given drugs for 7 d.Rats were injected with caffeine,chlorzoxazone,and midazolam solution in tail vein 30 rain after the last administration,and the blood was collected at different time points.Metronidazole as internal standard,method has been established to determine the levels of caffeine,chlorzoxazone,and midazolam to evaluate the activities of CYP1A2,CYP2E1,and CYP3A4 by HPLC.Results Compared with control group,SMR increased the clearance rates (CL) of caffeine,chlorzoxazone,and midazolam,reduced the AUC,and t1/2 was also show a decreasing trend,but the difference was not significant.In CF group,CL of caffeine and chlorzoxazone was decreased,but the difference is not significant.CL of midazolam significantly decreased (P ＜ 0.01).AUC of chlorzoxazone increased,but the difference was not significant.AUC of caffeine and midazolam increased significantly (P ＜ 0.05 and 0.01).In SMR + CF group,the CL of caffeine and chlorzoxazone decreased significantly (P ＜ 0.05),the AUC of caffeine and chlorzoxazone increased significantly (P ＜ 0.05),and t1/2 also showed a decreasing trend,but the difference is not significant.Conclusion Compatibility of SMR and CF has an inhibitive effect on CYP1A2 and CYP2E1 in rats,and it could be one of the mechanisms ofinteractive synergy.

OBJECTIVETo analyze the genetic relations of Shigella isolated from Shenzhen in 2001-2006 and develop primary molecular subtyping surveillance network of Shigella.

METHODSChromosomal DNAs from 55 isolated in agarose were digested with the restriction enzyme Xba I, and then were analyzed by pulsed-field gel electrophoresis. Pulsed-field gel electrophoresis (PFGE) patterns were clustered using BioNumerics software.

RESULTSAll 41 distinctive PFGE patterns were identified among 55 strains. 32 strains belonged to one cluster. Differences were observed in other strains.

CONCLUSIONBoth genetic-related clones and non-related clones of Shigella existed in Shenzhen. The development of PFGE molecular subtyping surveillance network would contribute to the active surveillance, outbreak investigation and source tracking for Shigellosis.

Bacterial Typing Techniques ; China ; Electrophoresis, Gel, Pulsed-Field ; methods ; Feces ; microbiology ; Humans ; Shigella ; classification ; isolation & purification

AIMTo study the stereoselectivity of skin carboxylesterase metabolism and its molecular biological foundation for improving drug percutaneous absorption.

METHODSKetoprofen ethyl ester was used as a model drug, and skin homogenate was applied for studying the stereoselectivity of carboxylesterase metabolism. Human liver L02 cell was used as control of carboxylesterase expression, and RT-PCR was used for studying the expression of carboxylesterase.

RESULTSThe main metabolite of ketoprofen ethyl ester in human skin homogenate was R-ketoprofen. Human carboxylesterase-2 was highly expressed in skin and its cells. However, the expression of human carboxylesterase-1 was very weak or not detectable.

CONCLUSIONHuman carboxylesterase-2 is the main hydrolytic enzyme of prodrugs in percutaneous absorption, and shows metabolic stereoselectivity to prodrugs with chiral esters.

Adult ; Carboxylesterase ; genetics ; metabolism ; Cell Line ; Cells, Cultured ; Humans ; Ketoprofen ; metabolism ; Liver ; cytology ; enzymology ; Prodrugs ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Skin ; enzymology ; Stereoisomerism

BACKGROUNDThe mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved.

METHODSMedian effective doses (ED(50)) of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6 - 10 were cultured for breeding sensitive offspring (S(1)). So did median ones of percentile 48 - 52 for breeding median offspring (M(1)), resistant ones of percentile 91 - 95 for breeding resistant offspring (R(1)). Process was repeated through 31 generations, in the 37th generation, S(37), M(37) and R(37) were used to determine ED(50) for enflurane, isoflurane, sevoflurane, desflurane, halothane, methoxyflurane, chloroform and trichloroethylene, then ED(50) values were correlated with minimum alveolar concentration (MAC) values in human.

RESULTSFrom a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20:1.00:0.53 for females and 1.22:1.00:0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED(50) values in three strains correlated directly with MAC values in human.

CONCLUSIONSThree Drosophila melanogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED(50) are directly correlated with MAC in human for eight volatile anesthetics.

Anesthetics, Inhalation ; pharmacology ; Animals ; Chloroform ; pharmacology ; Drosophila melanogaster ; drug effects ; growth & development ; Enflurane ; pharmacology ; Female ; Halothane ; pharmacology ; Isoflurane ; analogs & derivatives ; pharmacology ; Male ; Methoxyflurane ; pharmacology ; Methyl Ethers ; pharmacology ; Trichloroethylene ; pharmacology

Objective To study the role of arrestin domain-containing protein 4( ARRDC4) in regulation of enterovirus 71(EV71) triggered innate IL-6 production and the underlying mechanism .Methods THP-1-derived macrophages (t-M?) were transfected with ARRDC4 specific siRNA and negative control siRNA .The expression and production of IL-6, replication and virus titer of EV71, and the activation of signaling pathway adaptors were analyzed with quantitative real -time PCR, ELISA and Western blot.Results Upon EV71 infection, ARRDC4 was upregulated.ARRDC4 silencing could enhance mRNA expression and production of IL-6, thus increasing the replication and virus titer of EV71.In ARRDC4 silenced t-M?, the activation of p-65,IκBα,ERK,JNK and p38 was promoted.Conclusion ARRDC4 promotes EV71-t riggered IL-6 production by enhancing the activation of NF-κB and MAPK signaling pathway to inhibit EV71 infection, contributing to positive regulation of anti-EV71 innate immune responses .

AIMTo study the effects of hydrocortisone sodium succinate on sodium current in human atrial myocytes and in guinea pig ventricular myocytes.

METHODSSingle cardiac myocytes were isolated by enzyme. The effects of hydrocortisone sodium succinate on sodium current (INa) were assessed by applying whole-cell patch clamp techniques.

RESULTSHydrocortisone sodium succinate (1, 3, 10 micromol x L(-1)) was shown to inhibit INa of both human atrial myocytes and guinea pig ventricular myocytes in concentration dependent manner and the IC50 were 6.97 and 8.74 micromol x L(-1), respectively. The inhibition effects acted quickly (1-3 min) and the maximal activating voltage of INa was not changed in both human and guinea pig cardiac myocytes.

CONCLUSIONHydrocortisone sodium succinate can exhibit inhibitory effects on INa in both human and guinea pig cardiac myocytes, and its inhibitory effects act rapidly, which are not consistent with genomic effects, so there may be nongenomic effects.

Adolescent ; Adult ; Animals ; Cell Separation ; Child ; Child, Preschool ; Guinea Pigs ; Heart Atria ; pathology ; Heart Defects, Congenital ; pathology ; Heart Ventricles ; cytology ; Humans ; Hydrocortisone ; analogs & derivatives ; pharmacology ; Myocytes, Cardiac ; drug effects ; physiology ; Patch-Clamp Techniques ; Sodium Channels ; drug effects