BACKGROUND: With the development of tissue engineering, more attention has been paid to tooth regeneration. However, the resource of best seed cells is still uncertain. Therefore, alternative sources should be attached to intensive investigation. OBJECTIVE: To review the feasibility of stem cells from umbilical cord blood as seed cells for tooth regeneration. METHODS: A PubMed search was performed for articles published between January 1998 and January 2009. Key words were "tooth regeneration, seed cells, tissue engineering, umbilical cord blood, mesenchymal stem cells". Only studies written in English were included. Simultaneously, databases of China National Knowledge Infrastructure, Wanfang, and VIP published between January 1998 and January 2009 were also retrieved, using the key words of "tooth regeneration, seed cells, tissu engineering, umbilical cord blood, mesenchymal stem cells". Only studies written in Chinese were included. Totally, 40 literatures were included. RESULTS AND CONCLUSION: Seed cells, such as odontoblasts from dental germ, stem cells from dental pulp and deciduous teeth, and ectomesenchymal cells from the firstbranchial arch showed odontogenic differentiation potential in basic research. However, these cells are not practical to harvest in clinic. Although bone marrow mesenchymal stem cells have odontogenic capacity, their differentiation abilities significantly decrease with the increasing age of the donors. Stem cells from umbilical cord blood have many clinical advantages over bone marrow mesenchymal stem cells, and exhibited typical mesenchymal stem cells characteristics. Thus, we propose the hypotheses that stem cells from umbilical cord blood could be induced into odontogenic lineage and might be used as suitable seed cells for tooth regeneration to replace the lost tooth.

AIM:To discover the effect of MCPH1 on the DNA damage induced by ionizing radiation in esoph-ageal cancer cells.METHODS:ECA109 cancer cells were radiated at dose of 8 Gy.The nuclear foci of relevant factors were detected 1 h after irradiation in the ECA109 cells after silence of MDC1 gene.A cell line was established that was sta-ble low expression of MCPH1.The nuclear foci induced by ionizing radiation after silence of MCPH1 were determined.RE-SULTS:The MCPH1 gene silenced ECA109 cell line was successfully constructed.A strong relationship between MDC1, MCPH1 andγ-H2AX was observed 1 h after 8 Gy irradiation.Silence of MDC1 did not affect the nuclear foci formation ofγ-H2AX and MCPH1.The nuclear foci of MDC1 but notγ-H2AX significantly reduced after silencing of MCPH1.CON-CLUSION:MCPH1 is located in the downstream of H2AX and upstream formation of MDC1, and regulates the nuclear fo-ci formation of MDC1 during DNA damage response.

Objective To investigate the effect of penehyclidine hydrochloride (PHC) on iNOS expression in lung in septic mice.Methods Female KM mice were subjected to cecal ligation and puncture (CLP,a model of polymicrobial sepsis) or shame operation.Thirty-six KM mice weighing 20～25 g were randomly assigned into three groups:shame CLP group,CLP group and PHC group.Mice in PHC group were given PHC 0.45 mg/kg intraperitoneally at 1 h before CLP. Six hours after CLP,the lungs of each group were sampled for light and electronic microscopy.The expression of iNOS mRNA in lung tissue were detected by in situ hybridization.The survival rates were observed at 24 h after the operation. Results The CLP group was observed thickened alveolar septa,as well as mitochondrial cristae swelling and mitochondrial vacuolation under electronic microscope.Emptied lamellar bodies could be also found.Histology of lung in PHC group had little changed.Expression of iNOS in lung in PHC group was significantly lower than that of the CLP group.At 24 h after CLP challenge,70.0% of the PHC mice lived,remarkably increased compared with that of the CLP group (26.7%),P＜0.05.Conclusion PHC had effective effect for increasing the survival rates of septic mice,inhibiting the expression of iNOS and reducing the severity of lung injury.

Objective To evaluate the clinical effects of sitagliptin and sitagliptin combined with glimepiride in the treatment of type 2 diabetes (T2DM).Methods Ninety-two patients with T2DM were randomly divided into sitagliptin group (group J),glimepiride group (group G) and sitagliptin combined with glimepiride group (group U),group J took sitagliptin,group G took glimepiride,group U took sitagliptin and glimepiride.Before and after treatments,blood glucose and insulin were determined in the fasting and 2-hour blood samples after taking glucose (fasting blood-glucose (FPG),2-hour postprandial blood glucose (2hPG),insulin (FIns),2-hour postprandial insulin (2hIns),and glycosylation hemoglobin (HBA1 c) were also determined and homeostasis model assessment was applied to estimate the functions index of islet β cell(HOMA-β).Results The levels of blood glucose and HBA1C in three groups decreased after treatments(FPG,(before treatment:(9.2±3.0),(9.2±2.8),(9.3±3.2) mmol/L),(after treatment:(7.7 ± 3.0),(6.9 ± 2.6),(6.0 ± 2.5) mmol/L),and t values are 2.205,3.203,3.691,P ＜ 0.01,P ＜ 0.05 ;2 hPG (before treatment:(14.1 ± 5.7),(14.8 ±6.3),(15.0±6.8) mmol/L),(after treatment:(7.9 ±2.9),(9.0 ±3.1),(7.1 ±3.1) mmol/L),and t values are 3.881,3.159,4.189,P ＜ 0.01 ; HBA1c (before treatment:(8.52 ± 2.01)％,(8.48 ± 1.94)％,(8.56 ±2.27)％,(after treatment:(7.64 ± 1.92)％,(6.81 ± 1.55)％,(6.19 ± 1.84)％),t values are 2.292,2.184,3.269,P ＜ 0.01,P ＜ 0.05) ; HOMA-β in the three groups increased after treatment ((before treatment:1.42 ± 0.07,1.44 ± 0.06,1.41 ± 0.11),(after treatment:1.76 ± 0.14,1.68 ± 0.20,1.85 ±0.17),t values are 2.180,2.073,2.882,P ＜ 0.01,P ＜ 0.05);levels of HBA1c and blood glucose in group U were lower than those in group J and G(HBA1 c:t values are 2.785,2.138,P ＜ 0.05,P ＜ 0.01 ;FPG:t values are 2.252,2.346,P ＜0.05;2hPG:t values are 2.147,2.829,P ＜0.01,P ＜0.05),HOMA-β in which was higher than that of group G(t =2.153,P ＜ 0.05),but with no significant difference compared with group J (t =1.796,P ＞ 0.05),levels of HBA1C,FPG and HOMA-β in group J were higher than those of group G (t values are 2.108,2.202,2.121,P ＜ 0.05),level of 2hPG of group J was lower than that of group G(t =2.307,P ＜ 0.05).Conclusion Sitagliptin provides significant glycaemic control,together with glimepiride,clinical effect of treatment of type 2 diabetes will be enhanced.

Objective To develop the quality standard for evaluating Huangdi cataplasm. Methods Thin layer chromatography (TLC) was used to qualitatively identify Astragalus membranaceus (Fisch.) Bunge,Rheum palmatum Linn,Rhizoma Chuanxiong,Angelica sinensis and Resina Draconis in Huangdi cataplasm.HPLC method was used to determine astragaloside A and loureirin B in Huangdi cataplasm. Results The Astragalus membranaceus (Fisch.) Bunge,Rheum palmatum Linn,Rhizoma Chuanxiong,Angelica sinensis and Resina Draconis were well separated by TLC without interference in the negative control.content of Astragaloside A and loureirin B showed good liner relationships with respective peak area within the range of 6.96-23.2 μg,and 0.072-0.648 μg,with r = 0.999 5,r = 0.999 9, respectively;and the average recovery was 97.18%,and 96.93%,RSD was 1.21%(n= 6),1.53% (n = 6 ), respectively. Conclusion The established qualitative and quantitative detection method is simple, specific, reproducible, accurate and reliable, which can be used for quality control of Huangdi cataplasm.

Objective To discuss the curative effect and specificity of interventional therapy for deep venous thrombosis (DVT) of lower limb in burned patients.Methods The clinical data of 13 patients with lower limb DVT after burn,including 7 males and 6 females with a median age of 46.1 years (37-67 years),were retrospectively analyzed.The causes of burn included flame burn (n=9),electric injury (n=2) and hydrothermal bum (n=2).The burned area was 1％-88％ of the total body surface,with a mean of (37.08± 30.60) ％.Lower limb DVT complicated by lower limb bum was observed in 11 patients,among them bum of both lower limbs was seen in 8 patients.Lower limb DVT associated with inhalation injury was found in 5 patients.Clinically,lower limb DVT was usually detected in 13-72 days after burn,with a mean of (38.69± 16.83) days.Interventional treatment was carried out in all 13 patients,and the curative effect was assessed.Results Technical success of interventional treatment was obtained in all 13 patients.Both inferior vena cava filter placement via right internal jugular vein approach (n=3) or via unaffected-side femoral vein approach (n=10) and anticoagulant therapy were conducted.Catheter-directed thrombolysis was employed in 7 patients,intravenous thrombolysis was adopted in 4 patients,and no thrombolysis therapy was used in 2 patients.No pulmonary embolism occurred.The curative effect rate of interventional treatment was 84.6％(11/ 13).Conclusion For the treatment of lower limb DVT after burn,interventional therapy is safe and reliable,but the selection of puncture site and the use or not use of indwelling catheter for thrombolysis should be carefully taken into consideration.

Objective To investigate the effect of berberine on gut microbiota and T helper cell 17 (Th17), regulatory T cell (Treg) cell in sleep deprived rats.Methods SD rats were randomized into control group, model group, low-dose and high-dose group (BBR1 and BBR2, 100 mg/kg and 200 mg/kg, administrated orally).Sleep deprived rat model was established by the small-platforms-over-water method.The number of bacteria in rectum content of rat was detected.The ratio of Th17/Treg was evaluated by flow cytometry.The expression of interleukin 17 (IL-17), RAR-related orphan receptor (ROR) C, and Forkhead Box Protein P3 (Foxp3) mRNA was evaluated.Results The counting of Clostridium perfringens was elevated (P<0.05), the amount of other microbiota decreased (P<0.05), Th17/Treg ratio(P<0.05), IL-17 and RORC expression enhanced (P<0.05), Foxp3 expression decreased (P<0.05) in the gut of model rats.In contrast, treatment with berberine inhibited the proliferation of Clostridium perfringens(P<0.05), and promoted the growth of other microbiota (P<0.05), and dampened Th17/Treg ratio (P<0.05), regressed IL-17 and RORC expression, augmented Foxp3 expression.Conclusions Various doses of berberine can counteract gut microbiota imbalance and Th17/Treg imbalance induced by sleep deprivation.

Objective To investigate the role of rotational alignment reference landmarks of the proximal tibia in total knee arthroplasty.Methods Fifteen healthy adult volunteers were enrolled in this study,including 10 males and 5 females,aged from 21 to 38 years (average,28.1±6.0).CT scans of 26 knees were taken as the knees were placed in full extension.Two anteroposterior axes were drawn on the CT images:one line connected the middle of the posterior cruciate ligament insertion site and the medial edge of the patellar tendon,and another line connected the middle of the posterior cruciate ligament insertion site and the middle-medial 1/3 of the patellar tendon.The surgical epicondylar axis was also drawn on the CT images.Angles were measured between a line perpendicular to the surgical epicondylar axis and the two anteroposterior axes,and the angles were compared with the ideal tibial rotational alignment reference axis (0°).Results Angles between the line perpendicular to the surgical epicondylar axis and the line connecting the middle of the posterior cruciate ligament insertion site and the medial edge of the patellar tendon averaged 0.7°±2.8° (range,-5.1°-5.8°),there was no significant difference compared with 0°.Angles between the line perpendicular to the surgical epicondylar axis and the line connecting the middle of the posterior cruciate ligament insertion site and the middle-medial 1/3 of the patellar tendon averaged 6.9°±5.3° (range,-3.4°-14.1°),there was significant difference compared with 0°.Significant difference existed in angles between the two anteroposterior axes and the line perpendicular to the surgical epicondylar axis.Conclusion The line connecting the middle of the posterior cruciate ligament insertion site and the medial edge of the patellar tendon is a more reliable reference axis for the tibial component rotational alignment,which makes the femoral and tibial components in a more matching rotational position.

Objective To discuss the standard of endoscopic diagnosis of duodenal white spot syndrome and to test its accuracy by pathological diagnosis standard. Methods A total of 6,995 patients undergoing gastroscopy were detailedly examined through gastrofiberscope or electrogastroscope and endoscopic diagnosis were made by the standard of endoscopic diagnosis of duodenal white spot syndrome. Then, pathological examination was done to test and verify the accuracy of the standard of endoscopic diagnosis. Results There were 533 patients suffering from duodenal white spot pathological changes, accounting for 7.62%. And duodenal mucositis was confirmed by pathological findings in all 90 cases of the patients undergone their biopsy at the same time. Conclusions The appropriate standard of endoscopic diagnosis can improve the detection rate of duodenal white spot syndrome and there is a high coincidence rate between endoscopic diagnosis and pathological diagnosis.

Objective To determine if stimulation of cholinergic anti-inflammatory pathway mediated by vagus can protect liver against sepsis.Methods Male SD rats weighing 250-300 g were anesthetized with intraperitoneal methane 1g?kg~(-1).Left common carotid artery,was cannulated for MAP monitoring and blood sampling.Sepsis was produced by ligation of cecum which was punctured twice at an interspace of 3 mm with a 9G needle(CLP).Bilateral vagus nerves were isolated,ligated with 4-0 silk and cut(VGX).The distal end of the vagus nerve was stimulated with direct current(5V,2 ms,1 Hz)continuously for 20 min(STM).Forty animals were randomly divided into 4 groups(n=10 each):group Ⅰ sham operation;group Ⅱ CLP;group Ⅲ CLP + VGX and group Ⅳ CLP+VGX+STM.Arterial blood samples were obtained at 0,1,2 and 4 h after operation for determination of plasma TNF-? concentration and serum ALT and AST activities.The animals were then killed and the livers removed for ultrastructure examination with electron microscope.Results Electrical stimulation of the distal end of vagus nerve significantly attenuated the significant decrease in MAP and increase in plasma TNF-? concentration and serum AST and ALT activities and the damage to the organelle in the liver cell induced by sepsis.Conclusion Our results show that electrical stimulation of vagus nerve can protect liver from sepsis to some extent through cholinergic anti-inflammatory pathway.