BACKGROUND:In the treatment of early caries, fluoride can be used for remineralization of white spot lesions. Varnish XT (durable fluoride-releasing coating) and ICON penetration resins are two new materials. Varnish XT as a new type of resin reinforced glass ionomer can be selected as mineralized material. ICON penetration resin is a high-permeability resin with good liquidity that can infiltrate by capilary action into the pores created by enamel demineralization. Low-viscosity resin is used to replace the lost hard tissue due to demineralization and occupy the micropores, so as to fil the region of enamel demineralization and prevent further development of lesions. OBJECTIVE:To study the effects of two minimaly invasive surgical treatment materials, Varnish XT and ICON penetrating resin, on the microhardness of enamel caries white spot. METHODS:Totaly 100 incisors of cows were selected, embedded with ethoxyline resin and polished. The lip side facing down served as the observation side. An area of at least 6 mm×10 mm on the enamel face was exposed, and there were five regions from incisal to dental cervix, A, B, C, D, E. After demineralization liquid for artificial caries, no treatment was adopted in region A, treatment with Varnish XT was for region B, treatment with ICON penetrating resin for region C, treatment with fluoride for region D, and region E was sealed with antacid nail. Surface micro-hardness was detected. RESULTS AND CONCLUSION: After demineralization, surface micro-hardness of regions A, B, C, D decreases remarkably as compared with region E (P < 0.05). Surface micro-hardness of regions B, C, D was higher than that of region A, and ranged as folows: C > B and D for surface micro-hardness with statistical significance (P < 0.05). There was no statistical significance of surface micro-hardness between regions B and D (P > 0.05). ICON resin infiltration, Varnish XT and fluoride have obvious improvement effects on surface micro-hardness, and ICON resin infiltration is superior to Varnish XT and fluoride.

Objective To explore the methods and mesures for the pre-analytical quality control of test specimen and to improve the accuracy and reliability of test results.Methods According to the relevant requirements of IS015189,various measures for the specimen circulation process and collection technology two aspects were taken to control the full links of clinical specimen collection and transport,and the incidence of unqualified specimen before and after the improvements were analyzed.Results After the imple-mentation of the improvement measures,the incidence of unqualified specimens was decreased significantly.Conclusion Implemen-tation of the whole aspect of pre-analytical quality control can effectively improve the quality of specimen in order to improve the test quality.

Objective To investigate the expression and clinical significance of Smac and HtrA2 in children with acute leukemia(AL).Methods Bone marrow samples were obtained from 77 children with AL (including 32 newly diagnosed children,33 complete remission children and 12 relapsed children)and the control group of 15 children without malignant blood disease.The expressions of Smac and HtrA2 protein were measured by streptavidin/peroxidase immunoperoxidase technique(SP) in all children.SPSS 13.0 software was applied to analyze the statistical data.Results Protein Smac was detected only in some samples,but HtrA2 was detected in all samples.The levels of Smac and HtrA2 protein in newly diagnosed AL children were both higher than those of the complete remission children (x2 =17.38,F =2.36,all P ＜ 0.05) and normal controls (x2 =12.89,F =5.26,all P ＜ 0.05),there was a statistical significance,but compared with those in the relapsed children,the difference had no statistical significance (x2 =1.18,F =1.57,all P ＞ 0.05).The levels of Smac and HtrA2 protein in complete remission children were both higher than those of the normal controls,and the difference had no statistical sigmficance(x2 =1.20,F =2.23,all P ＞ 0.05).In the newly diagnosed children,the levels of Smac and HtrA2 protein in children with acute lymphocytic leukemia(ALL) were higher than those of the acute myeloid leukemia(AML),but the differences had no statistical significance(x2 =0.113,t =1.024,all P ＞ 0.05).In newly diagnosed AL children,the complete remission(CR) rate of the negative expression of Smac(Smac-,90.9％) and the low expression of HtrA2(HtrA2low,84.6％) in the level of protein were higher than those of the positive expression of Smac(Smac +,47.6％) and the high expression of HtrA2 (HtrA2high,47.4％),and there was statistical significance respectively(x2 =5.772,4.596,all P ＜ 0.05).The CR rate of Smac-HtrA2low group (100％) was higher than that of Smac+ HtrA2high group(30.8％)in the children with AL,and the statistical data were of great significance(x =9.692,P ＜0.01).The protein level of Smac in newly diagnosed AL children was correlatedwith HtrA2 (r =0.979,P ＜ 0.001).Conclusions Pro-apoptotic protein Smac and HtrA2 may be involved in and af-fected each other in the pathogenesis and progression in AL,but levels of Smac and HtrA2 protein may be not correlatedwith the types of AL.In newly diagnosed AL children,the high expression of protein Smac and HtrA2 predicts poorprognosis.

Objective To explore the sensitivity of a little amount of subarachnoid hemorrhage (SAH) between CT and different MR sequences through animal experiment,to find a more sensitive way to diagnosis SAH.Methods 18 healthy adult white New Zealand rabbits were randomly divided into two experimental groups(group A and group B) and one control group(group C).Rabbit SAH model was established by injecting blood into the cisterna magna one time.All rabbits underwent CT and MR scan at 2 hours,48 hours after operation.The findings on CT and different MR sequences were observed and recorded.Results ①In experimental groups(group A and group B),MR FLAIR sequences in the diagnosis of a little amount of SAH was more sensitive than that on MR T1WI,T2WI and CT in acute phase.And the diagnosis sensitivity between MR FLAIR and CT was statistically significant(P<0.05).②Abnormal signs of SAH could not be found in group C.Conclusion ①Rabbit SAH model was established successfully which will be the foundation for the follow-up study of medical imaging.②MR FLAIR sequence is more sensitive to diagnose a little amount of SAH in acute phase,and may be used in the routine diagnosis of SAH in acute phase.

Objective To analyze the clinical and laboratory manifestations of primary Sj(o)gren's syndrom (pSS) with neurological involvement.Methods One hundred and forty eight patients fulfilling the 2002 American-European pSS classification criteria were retrospectively analyzed.Neurological manifestations were diagnosed based on the clinical,biological,electrophysiological,and imaging findings.Biographical,clinical,and laboratory data were compared between patients with and without neurological manifestations.Statistical methods used were Mann-Whitney U test,Chi-square test and Fisher exact probability.Results The prevalence of neurological involvement in pSS was 20.3％ (30/148),and the incidence of peripheral neuropathy,the central neuropathy and combination of the central neuropathy with peripheral neuropathy were 10.1％(15/148),9.5％(14/148) and 0.7％(1/148),respectively.The clinical spectrum of peripheral neuropathies encountered in Sj(o)gren's syndrome (SS) patients varied,with the pure sensory neuropathies being the most common,followed by sensorimotor neurophathies.Motor neuron disease was the most common type of central neurophathies.Compared with those without neurological manifestations,the duration of peripheral nerve system/central nerve system (PNS/CNS)-pSS patients was relatively short [(55±76) months vs (100±108) months,Z=-2.682,P＜0.05],and the antinuclear antibody (ANA) titer and RF titer were lower [(234±248) vs (377±339),Z=-2.008,P＜0.05;(126±279) U/ml vs (359±1 445) U/ml,Z=-2.243,P＜0.05].In PNS/CNS-pSS patients,the most common clinical manifestations included numbness (50％),pain (23％),and muscle weakness (63％).Conclusion The prevalence of neurological involvement in pSS is high.The duration is relatively short and the disease activity is high,but the disease features are atypical and may be neglected by rheumatologists.

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.

Objective To analyze the CT imaging features of Castleman disease and enhance our knowledge of Castleman disease.Methods Twenty two patients with lymph node biopsy-proved or surgeryproved Castleman disease were retrospectively reviewed in this study.Of the 22 patients,18 had localized lesion and 4 patients had multicentric lesions.Correlation was made between CT and pathologic findings.Results Eighteen patients with localized Castleman disease had the hyaline-vascular type and showed well-circumscribed masses with soft-tissue density [mean CT value,(45 ± 16) HU],punctate or bifurcate calcification and linear low-density areas on non-enhanced CT images.All localized masses showed significant enhancementwith an increase of(56 ± 22)HU on arterial phase and showed residual enhancement and some low-density areas on delayed phase.Enhancing patterns were variable,including homogeneous enhancement,gradual enhancement from the edge to the center of mass and heterogeneous enhancement.Four patients with localized lesion demonstrated enhancing vessels around masses.Four patients with muhicentric CD belonged to the plasma cell type and had multiple enlarged lymph nodes.Plasma cell type masses with homogeneous density also showed enhancement after injection of contrast media but appeared to reveal a less increase of (32 ± 10) HU than the hyaline vascular type.Conclusions The localized Castleman disease showed certain characteristics on CT imaging includingcalcification and contrast enhancing patterns,which could help in the differential diagnosis of this disease.The muhicentric Castleman disease did not reveal any useful imaging features.

Objective To study the relationship between DNA methylation and pathogenesis of childhood immune thrombocytopenic purpura (ITP) by examining the expression of DNA methyltransferase 1(Dnmt1) and DNA methyltransferase 3a (Dnmt3a) mRNA in peripheral blood lymphocytes of the children with ITP. Methods Expression of Dnmt 1 and Dnmt3a mRNA in the peripheral blood lymphocytes in 36 children with newly diagnosed ITP and 26 healthy children were detected using RT-PCR. Results Dnmt1 mRNA expression in peripheral blood lymphocytes in children diagnosed with ITP was 3.02±0.49, significantly lower than 4.58±0.52 in the control group (t=11.95, P<0.001). Dnmt3a mRNA expression in peripheral blood lymphocytes in children diagnosed with ITP was 1.49±0.44, signiifcantly lower than 2.41±0.32 in the control group (t=9.12, P<0.001). Conclusions Children with newly diagnosed ITP have lower DNA methylation status in peripheral blood lymphocytes as compared to that in healthy children. The DNA methylation may play an important role in the etiology of acute ITP in children.

Objective To discuss DNA methylation's effect on pathogenesis of pediatric immune thrombocytopenia (ITP)through detecting the expression level of DNA methyltransferases (DNMTs)mRNA in peripheral blood lymphocytes of children with ITP.Methods Two mL peripheral blood was collected from each of 25 children with persistent and chronic ITP and 20 healthy children (the healthy control group)by using aseptic method in the pediatric ward of the First Affiliated Hospital of Xinxiang Medical University from January 2014 to January 2015.First ethylene diamine tetraacetic acid (EDTA) was used as the anticoagulant.Then separate the mononuclear cells,extract RNA and detect expression levels of DNMT1,DNMT3A and DNMT3B mRNA using reverse transcription-polymerase chain reaction (RT-PCR) method.Results (1) The blood platelet (PLT) of children with persistent and chronic ITP was (36.2 ± 19.6) × 109/L,which was obviously lower than the healthy control group(168.8 ±46.8) × 109/L(t =-11.85,P =0.000).(2)The DNMT1 mRNA expression level of children with persistent and chronic ITP was 0.17 ± 0.05,which was obviously lower than the healthy control group (0.27 ± 0.10) (t =-3.912,P =0.001).The DNMT3A mRNA expression level of children with persistent and chronic ITP was 0.20 ± 0.10,which was obviously lower than the healthy control group (0.32 ±0.11) (t =-3.779,P =0.000).The DNMT3B mRNA expression level of children with persistent and chronic ITP was 0.16 ± 0.1 1,which was obviously lower than the healthy control group (0.31 ±0.11) (t =-4.641,P =0.000).(3) There was positive correlation between the expression of DNMT1 and DNMT3B mRNA(r =0.433,P =0.031).There was positive correlation between the expression of DNMT3A and DNMT3B mRNA(r =0.721,P =0.000).Conclusions (1) Children with persistent and chronic ITP have lower expression levels of DNMT1,DNMT3A,DNMT3 B mRNA,which indicates that DNA methylation contributes to the pathogenesis of pediatric persistent and chronic ITP.(2) DNMTs have synergistic effect on DNA methylation of pediatric persistent and chronic ITP.

BACKGROUND:The periodontal ligament stem cels can promote periodontal tissue regeneration, providing a new way for the treatment of periodontitis. OBJECTIVE:To observe the inflammatory microenvironment effects on the biological properties of periodontal ligament stem cels. METHODS: Periodontal ligament stem cels from healthy controls and patients with periodontitis were primarily cultured by tissue digestion method, purified using limited dilution method, and identified through detection of CD146 and STRO-1. Then, passage 3 cels were taken and denoted as normal control and inflammation groups folowed by osteogenic induction. RESULTS AND CONCLUSION:Purified cels from two sources both expressed STRO-1 and CD146. Periodontal ligament stem cels in the inflammation group showed higher multiplication capacity, but the osteogenesis ability was lower compared with the normal control group. The expressions of Runx2 mRNA and Osterix mRNA were dropped significantly after the stimulus of tumor necrosis factor-α (P < 0.05), but the interleukin-1β and interleukin-6 did not have a significant impact. Tumor necrosis factor-α at 0.1 and 1 μg/L had no significant effects on the expression of Runx2 mRNA, but the expression of Runx2 mRNA was decreased significantly after treatment with 10 μg/L tumor necrosis factor-α (P< 0.05). It is confirmed that the molecular signaling mechanism inside the periodontal ligament stem cels is changed under inflammatory microenvironment, so that the differentiation capacity of cels from the inflammatory sources is lowered. Moreover, tumor necrosis factor-α is one of the key factors and its optimalconcentration is 10 μg/L.