Objective: To investigate the capability of Streptococcus sanguis(S.s) producing hydrogen peroxide (HP) and screen the strains of S.s with high yield of hydrogen peroxide.Methods: S.s were isolated from supergingival plaque of people with healthy periodontium. The microorganisms were cultivated anaerobically or aerobically, then washed and incubated with KCl buffer. Hydrogen peroxide and bacterial proteins were assayed spectrophotometrically. S.oralis ATCC 10557 was used as the controls. Results: In anaerobical culture the HP production (nmol/?g) of S.s and S.oralis was 118.22?69.92 and 338.60?192.14( P

Objective:To study the relationship between human cytome ga lovirus (HCMV) and chronic periodontitis. Methods: In 62 chronic periodontitis patients (27 male and 35 female), subgingival samples were colle cted from active periodontitis site,quiescent periodontitis site, and initial g ingivitis site of each subjects. Human cytomegalovirus was detected by nested - polymerase chain reaction method. Results: HCMV detectable ratio in the active periodontitis sites was significantly higher than that in the qui escent sites (38.7% VS 14.5%, P0.05).Conclusion:HCMV infection may be associated wi th the activity of chronic periodontitis.

Objective:To investigate the levels of IL-8 i n GCF in patients with chronic periodontitis and their relationship with subgingi val Porphyromonas gingivalis(Pg).Methods:10 GCF samples from periodontal healthy volunteers, 60 from the teeth with chronic periodontiti s in patients and 10 from the periodontal healthy teeth in the patients with chr onic periodontitis were collected. Subgingival plaque samples and clinical data on GI, PPD and CAL were obtained. A sensitive ELISA was used to measure IL-8 in GCF and a PCR method was employed to measure the amount of Pg.Resul ts:①Higher total amount of IL-8 in GCF was found in chronic periodonti tis subjects than that in healthy volunteers(P0.05). ②There was positive correlation between the total amount of IL-8 and clinical parameters (GI, PPD, CAL).③There was no correlation between the amount of Pg and the concentration or total amount of IL-8. Conclusions:I L-8 increases with the increace of GCF in the patients with chronic periodontit is, but is not related to Pg in subgingival plaque.

Objective To study the effect of SARS during pregnancy on the pregnant outcome. Methods Six pregnant women who suffered from SARS in the second or third trimester were observed. The fetuses and infants were followed up. SARS specific antibody and coronavirus RNA were detected in blood and pharyngeal secretion samples for both mothers and their infants. Results Among the 6 cases,2 were twins. Two cases were preterm birth,3 were fetal distress. One fetal death in one twin,the other fetus complicated with fetal growth restriction. None of the 7 neonates had asphyxia or any signs of SARS.SARS coronavirus IgG was positive in 7 mothers and 4 infants. SARS specific IgM and coronavirus RNA were negative in all 7 newborns. Physical and mental development in 3 premature infants was slightly delayed while normal in the 4 full-term infants. Conclusions SARS during pregnancy may have some harmful effects on the perinatal outcome. No intrauterine transmission of coronavirus has been found.

Objective To evaluate the cerebral protection of dexmedetomidine during craniotomy under general anesthesia in the patients with craniocerebral injury.Methods Sixty patients with craniocerebral injury,aged 30-50 yr,with body mass index of 18-25 kg/m2,of ASA physical status Ⅱ or Ⅲ,with Glasgow Coma Scale score of 6-12,scheduled for elective craniotomy under general anesthesia,were randomized into 2 groups (n =30 each) using a random number table:control group (group C) and dexmedetomidine group (group Dex).Anesthesia was induced with iv midazolam,propofol,cisatracurium and sufentanil.The patients were endotracheally intubated and mechanically ventilated.In group Dex,dexmedetomidine 1 μg/kg was infused intravenously over 10 min before induction of anesthesia,followed by infusion at a rate of 0.5 μg · kg-1 · h-1 until the end of operation.The equal volume of normal saline was given in group C.Immediately before beginning of surgery (T0),at the moment when the duramater was opened (T1),at 2 h after beginning of surgery (T2),at the duramater closing (T3) and at the end of surgery (T4),blood samples were obtained from the radial artery and jugular venous bulb for blood gas analysis,arteriovenous blood O2 difference and cerebral O2 extraction rate were calculated.The serum concentrations of S-100β were measured by ELISA.Results The serum concentrations of S-100β were significantly increased at T2-4 than at T0 in both groups.The serum concentrations of S-100β were significantly decreased at T2-4 in group Dex than in group C.The parameters of cerebral oxygen metabolism were all within the normal range in both groups.Conclusion Dexmedetomidine (1 μg/kg infused intravenously before induction of anesthesia,followed by infusion at a rate of 0.5 μg · kg-1 · h-1 until the end of operation) provides cerebral protection to some extent during craniotomy under general anesthesia in the patients with craniocerebral injury.

ObjectiveTo discuss the effects and security o f intra-anmiotic administration of pulmonary surfactant for neonatal respiratory distress syndrome prophylaxis.MethodsForty-five cases of pr eterm delivery with immature fetal lungs were divided into two groups. Fifteen w omen of the study group were administered one dose of pulmonary surfactant into the amniotic cavity and delivered in several hours. Nothing was injected into th e amniotic cavity of the 30 women in the control group. The proportion of NRDS, mortality and the time in hospital were analyzed to make clear whether there wer e any differences between the two groups.ResulstsThere was n o difference between the two groups for neonatal Apgar score. Foam test demonstr ated that the proportion of lung maturity of the neonates was:56.3%(9/16)in the study group, 13.3%(4/30)in the control group,(P

Dexmedetomidine (Dex) is a novel and highly selective o2-adrenoceptor agonist,it has anxiolytic,antisympathetic and certain analgesic effects,its sedative effect can lead to mimic natural sleep.Dex is widely applied in mechanical ventilation,invasive procedures and perianesthesia with other drugs by intravenous route.Recent basic and clinical researches show that Dex can be applied safely and effectively with local anesthetics in regional block,to improve anesthetic effect,promote stable hemodynamics and optimize postoperative analgesia.

Objective:To study the distribution of CD14 in human gingival fibroblasts (HGFs) and the effects of lipopolysaccharide(LPS) on mCD14 expression in HGFs in vitro. Methods:HGFs were in vitro cultured and exposed to LPS at 0.1-10 ?g/L.The expression of mCD14 in the cells was examined by immunohistochemistry staining and Western blot.Results:mCD14 was found on healthy human HGF cell membrane surface and LPS at 1 ?g/ml and 10 ?g/ml increased the expression of mCD14 in 1-12 h exposure.Conclusion:LPS may regulate mCD14 expression of HGFs.

Objective To develop a LC-MS/MS method for the determination of inosine in human plasma and to apply it in the isoprinosine pharmacokinetic researches .Methods With adefovir as the internal standard ,methanol -10 mmol/L ammonium ace-tate(15 :85 ,v/v) was adopted as the mobile phase .The chromatographic column was the Agilent SB-C18 column(5 μm ,150 mm × 4 .6 mm I .D .) .Electrospray ionization(ESI) source was applied and the detection was conducted by the multiple-reaction monito-ring(MRM) mode .The ion reactions for the quantitative analysis were m/z 135 .0-267 .3(inosine) and m/z 134 .1-272 .0(adefo-vir) .Results The linear range of plasma inosine was 10-3 000 ng/mL .The lower detection limit was 10 ng/mL .The inter-and in-tra-day precisions(RSD) were less than 5% .The average recovery rate was above 90% without the matrix effect .Conclusion This method has the strong specificity ,convenience in treating the sample and high sensitivity ,and is suitable for the inosine pharmacokinetic re-searches .

Objective To investigate the effect of metformin used during early pregnancy on pregnancy outcome of pregnant women with polycystic ovary syndrome (PCOS).Methods Two hundred and fifteen pregnant women with PCOS history were selected into our investigation from March 2007 to February 2010,among which,58 patients were taken as metformin group as they had taken metformin during early pregnancy,or with impaired glucose tolerance complicated by marked hyperinsulinemia and history of recurrent miscarriage.All patients in the study group received metformin (1.0～1.5 g/d) during early pregnancy.The rest 157 gravidas with PCOS history did not receive metformin as control group.The outcomes of pregnancy in the two groups were compared with x2 or t test.Results The early spontaneous miscarriage rate of metformin group was significantly lower than that of control group (5.2 ％ vs 28.7 ％,x2 =13.476,P＜0.01).There was no statistical difference in the rate of late abortion (6.90％ vs 6.4 ％ ),hypertension during pregnancy (3.9％ vs 4.9％),preeclampsia (3.9％ vs 3.9％),preterm birth (13.7％ vs 20.6％) and oligohydramnios (5.9％ vs 3.0％) between control group and metformin group (P ＞ 0.05 respectively).And there was no significant difference in neonatal birth weights [(2925±530) g vs (2910± 659) g],the rate of asphyxia (3.7％ vs 6.8％),malformation (0.0％ vs 0.9％),hypoglycaemia ( 5.6％ vs 6.8％),fetal macrosomia ( 1.9％ vs 3.4％),fetal growth restriction (5.6％ vs 6.0％) and rate of neonatal intensive care unit admission (18.0％ vs 27.4％) between the two groups (P＞0.05,respectively).The infants were followed up for 3 years and all are physically and mentally normal.Conclusions Metformin administration during early pregnancy might reduce the early spontaneous miscarriage rate of PCOS patients,and the adverse effects of metformin have not been identified on fetals and infants.