Objective To establish attenuated S. typhimurium expressing Helicobacter pylori (H.pylori) urease subunit B (UreB) and determine whether it could be used as oral vaccine against H.pylori Methods H.pylori (SS1 strain) UreB gene fragment amplified by PCR was cloned into the prokaryotic expression vector PTc 01 after sequencing, then transformed into attenuated S.typhimurium SL3261 to acquire SL3261/PTc 01 UreB. The expression of H.pylori UreB in SL3261 was detected by Western blot. Twelve weeks after oral immunization of mice, antibody responses were evaluated using serum and intestinal fluid by ELISA. In vitro stability of PTc 01 UreB plasmid in S. typhimurium SL3261 was confirmed by growing in Luria Bertani medium to 60 generations. Results The UreB gene fragment amplified by PCR was consistent with the sequence of the H.pylori UreB by sequence analysis. Enzyme digestion revealed that the correct PTc 01 UreB was obtained. Western blot showed that 61kD protein was expressed in SL3261/PTc 01 UreB which could be recognized by anti H.pylori UreB antiserum. Anti UreB IgA antibodies in mouse intestinal fluid and IgG antibodies in serum were determined by ELISA. After 60 generations of continuous culture, the recombinant plasmid PTc 01 UreB was stable in SL3261 and had no obvious toxicity. Conclusion The attenuated Salmonella typhimurium expressing H.pylori UreB may be used as oral vaccine against H.pylori infection.

Objective To study the interphase FISH of cells from aminotic fluid in the third trimester prospectively. Methods Amniotic fluid (5ml) was obtained in 32 pregnant women in the third trimester who underwent cordocentesis for karyotyping. FISH was performed on uncultured am niocytes and the results were compared with karyotypes. Results Abnormal aneuploid were identified in 6 cases among the 32 women. The FISH results were consistent with the karyotypes. Conclusions Interphase FISH in third-trimester amniocentesis can provide an accurate clinical diagnosis on common aneupoidies.

Objective To investigate the features of the enhancement of SHCC at triple-phase spiral CT scanning and compare its sensitivity in different phase.Methods The pre- and post-contrast CT scanning of the entire liver in 70 patients with SHCC was carried out with a helical CT scanner. The contrast material was infused at a rate of 3ml/s, followed by sequential arterial-, portal- and equilibrium- phase scans of the liver. The number of the detected lesions was calculated in each phase, the characterization of lesions in each phase was observed.Results Of the 82 detected SHCC, the sensitivity in three phases was 92.68%, 70.73% and 73.17% respectively. The sensitivity increased significantly to 95% by combining the detection of three phases. Conclusion Triple-phase contrast enhanced spiral CT can fully demonstrate the patterns of SHCC and improve its detection rate.

Objective To study the CT findings of late onset intracranial hemorrhage in vitamin K(Vit K) deficiency.Methods 56 cases of late onset intracranial hemorrhage in Vit K deficiency proved clinically were presented.There were 42 male and 14 female,age ranging 28～60 days.Brain CT scans were obtained in all 56 cases. Results Subarachnoid hemorrage(SAH) in 33 cases,subdural hemorrage(SDH) in 32 cases,intracerebral hemorrage(ICH) in 19 cases and inraventricular hemorrage(IVH) in 8 cases were found.The hemorragic amount was ranged 2～150 ml.Simple hemorrage was demonstrated in 26 cases,and multiple mixed hemorrage in 30 cases.The cerebral edema was displaied in 16 cases.Conclusion SAH,SDH and multiple mixed hemorrage are common seen in the late onset intracranial hemorrage in Vit K deficiency.

Objective To observe the effect of AS1411-mediated signal transduction and activator of transcription 3 (STAT3) antisense oligonucleotide (ASO) targeting tumor cells.Methods RNA was used as coupling molecules to link the targeting molecules AS1411 and effector molecules ASO.Prediction and analysis of the secondary structure of the pre-synthesis of chimeric molecules by RNA Structure software.Agarose gel electrophoresis was used to test the stability of chimeric molecules in serum and cell lysis solution.Using flow cytometry and confocal fluorescence microscope were used to estimate the internalization of AS1411-mediated STAT3 ASO.Inhibitory effect of ASO on the growth of tumor cells was detected by CCK-8 kit.RT-PCR and Western blot was used to measure the expression levels of tumor related genes.Results STAT3 ASOs mediated by AS1411 can enter tumor cells efficiently to inhibit the transcription and translation of C-myc,Cyclin D1,Bcl-xl and PD-L1 gene,and also can inhibit the growth of Du145 cells.Conclusions AS1411-mediated STAT3 ASO can enter tumor cells and act as anti-tumor medicine.

Objective To histomorphometricly assess changes occurred in the alveolar ridge following different methods of socket preservation and to compare them against natural healing without interventions. Methods The second、 third and fourth mandibular premolars were extracted from six beagles. Six extraction sites in each dog were randomly assigned to three treatments as follows:natural healing (T1), Bio-Oss Collagen (T2) and immediate implant with Bio-Oss (T3). Six month after surgery, the dogs were euthanized and tissue samples were sectioned, fixed and mounted, then were stained with toluidine blue. The histologic studies and morphological measurements were performed by using an optical microscope and a digital image software. Results Reabsorption in the buccal aspect of the alveolar crest of ridge was showed in all groups. With respect to the mean vertical bone loss of the buccal bone plate, T3 is lower than T1 and T2(P<0.001 ), while no significant differences were observed between T1 and T2. With regard to horizontal dimension of the alveolar process , a statistical significance could be found at 3mm and 4mm below the crest of ridge in group T1 and T3(P=0.017, P=0.042), while no statistical differences were found between other groups. Conclusions Both techniques of alveolar ridge preservation were not able to completely preserve the original bone volume after tooth extraction. Immediate implant placement in combination with Bio-Oss seems to have the potential to limit the reabsorption of the alveolar process efficiently , but the bone preserving effect of Bio-Oss Collagen is undesirable.

BACKGROUND:Poly(3-hydroxybutyrate) is approved as its excel ent biocompatibility, biodegradability and piezoelectric properties, but there are also some deficiencies, such as high breakability and poor hydrophilicity. METHODS:Poly(3-hydroxybutyrate) was mixed with different mass percentages of nanohydroxyapatite (0, 10%, 20%and 30%) to prepare new composite fibrous scaffolds through electrospinning process. The microstructure, group composition, crystal ine phase distribution, thermal properties and surface wettability of the scaffolds were detected. RESULTS AND CONCLUSION:Under the scanning electron microscope, with the increase of nano-hydroxyapatite content, more and more nano-hydroxyapatite particles were distributed evenly on the composite fiber surface;the fiber surface was basical y covered with nano-hydroxyapatite particles at the content of 30%, and the roughness of the fiber surface also increased. Results from differential scanning calorimetry and X-ray diffraction showed that the nano-hydroxyapatite reduced the crystal inity of poly(3-hydroxybutyrate) and the crystal tacticity, and this phenomenon became more evident with the increase of nano-hydroxyapatite content. Additional y, the higher the content of nano-hydroxyapatite content, the lower the contact angle and the higher the hydrophily. These findings indicate that the nano-hydroxyapatite/poly(3-hydroxybutyrate) ultrafine-fibrous scaffold using electrospinning technology can effectively improve the surface wettability and crystal inity of the material as wel as the material hydrophily and brittleness, and the higher the content of nano-hydroxyapatite, the more obvious the effect.

Objective To investigate the effect of dexmedetomidine on emergence agitation (EA) following sevoflurane anesthesia in children with cerebral palsy.Methods Fifty ASA physical status Ⅰ or Ⅱ children with cerebral palsy of both sexes,aged 2-12 yr,scheduled for elective muscle strength muscle tension adjustment method,were randomly allocated into 2 groups (n =25 each):control group (group C) and dexmedetomidine group (group D).Anesthesia was induced with iv injection of sufentanil 0.3 μg/kg,cisatracurium 0.15 mg/kg,and propofol 1.5 mg/kg.The patients were tracheal intubated and mechanically ventilated.Dexmedetomidine 0.5 μg/kg was intravenously infused over 15 min after induction of anesthesia in group D and the equal volume of normal saline was given in group C.The operation was begun at the end of administration.Anesthesia was maintained with inhalation of 2％-4％ sevoflurane and the concentration was adjusted to achieve a target BIS value of 45-60.The heart rate,systolic blood pressure and diastolic blood pressure were recorded before infusion of dexmedetomidine (T1) and at skin incision (T2).The extubation time,emergence time and consumption of sevoflurane were also recorded.The end-tidal sevoflurane concentration was recorded at T1,T2,and the end of operation (T3).The adverse cardiovascular events and occurrence of EA were also recorded.The degree of EA was assessed using the Pediatric Anesthesia Emergence Delirium (PAED) scale.The peripheral venous blood samples were collected at T1,T2,T3 and extubation (T4) for determination of the blood glucose level and serum cortisol concentration.Compared with group C,the emergence time and extubation time were significantly shortened,and the consumption of sevoflurane,end-tidal sevoflurane concentrations at T2 and T3,PAED scores,incidence of agitation,and the blood glucose level and serum cortisol concentration at T4 were significantly decreased in group D (P ＜0.05 or 0.01).There was no significant difference in the incidence of bradycardia or heart rate,systolic blood pressure and diastolic blood pressure at each time point between the two groups (P ＞ 0.05).Conclusion Dexmedetomidine can decrease the development and degree of EA following sevoflurane anesthesia in children with cerebral palsy.

Objective To investigate the clinical results of immediate loading of a single anterior implant. Methods 26 implants were placed into anterior sites. Provisional prosthesis were placed at the time of fixture placement. It did not occlude in any pathway. Restoration was for esthetic only, not for function. Results No fixture was lost since the immediate restoration was delivered, the minimum being 12 months and the maximum 72 months. Conclusion Clinical studies on the placement of immediate restoration in anterior implant of maxilla have revealed predictable results.

Objective To investigate the role of bone marrow mesenchymal stem cells (MSCs) transplantation in repairing injured intestinal mucosa of acute pancreatitis.Methods MSCs were harvested and cultured from femurs of male SD rats.Twenty female SD rats were divided into three groups,and serve acute pancratitis (SAP) model was induced by intraperitoneal injection of L-arginine (2 g/kg) twice.Twelve hours after SAP model established,MSC transplantation group (n=8) were injected MSCs (5 × 106 cell/rat) through tail vein for three days,and SAP group (n=6) were injected the same volume of saline through tail vein as control.Control group (n=6) were only injected the same volume of saline without any treatment.All the rats were sacrificed at 72 hours after model established.The small intestinal tissues were taken for HE staining and pathological score,the TNF-α mRNA and IL-1β mRNA expression level in small intestine and pancreas were tested by RT-PCR.Y chromo-some (Sry) gene in pancreatic and intestinal tissue was examined by polymerase chain reaction (PCR).Results The relative expression quantity of TNF-a mRNA and IL-1β mRNA in pancreas was significant higher in SAP group and MSC transplantation group than in control group (7.22 ± 1.99,3.46± 1.75 vs 1.32 ± 1.04 ; 2.71 ± 0.56,1.92 ± 0.28 vs 0.61 ± 0.45 ),the difference was statistically significant (F=18.375,F=22.701; P＜0.05).Compared with SAP group,the expression quantity of TNF-α mRNA and IL-1β mRNA in pancreas was significantly decreased in MSC transplantation group,the difference was statistically significant (P＜0.05).The relative expression quantity of TNF-α mRNA and IL-1β mRNA in small intestine was significantly higher in SAP group and MSC transplantation group than in control group (3.93 ± 1.08,2.13 ± 0.53 vs 0.68 ± 0.42 ; 2.44 ± 1.54,1.02±0.44 vs 0.60±0.14),the difference was statistically significant (F=21.772,F=6.132; P＜0.05).The expression of TNF-αmRNA and IL-1β mRNA in MSC transplantation group was lower than that in SAP group,the difference was statistically significant (P＜0.05).Compared with SAP group,pathological score indicated that small intestine injure was slighter in MSC transplantation group (3.83±0.28 vs 2.83±0.56),the difference was statistically significant (F=12.013,P＜0.05).Sry gene could be detected in the pancreatic and intestinal tissue of MSC transplantation group.Conclusion Allogeneic MSC transplantation group can inhibit Pro-inflammatory cytokines expression in acute pancreatitis,relieve the intestinal mucosa injury and may involve in the intestinal tissue repair.