OBJECTIVEThis study aims to investigate the caries status of the first permanent molar and primary tooth among 7- to 9-year-old children in Tangshan city and the correlation between caries of primary tooth and the first permanent molar.

METHODSA stratified cluster sampling method was used on the basis of the Basic Approach of Oral Health Survey of WHO and the Guideline of the Third National Oral Health Survey. A total of 10 primary schools were randomly sampled in clusters that included 51 primary school sampling spots in Tangshan. The caries status of 1 794 children aged 7 years to 9 years was examined.

RESULTSThe prevalence rate of the first permanent molar caries was 47.49% (852/1 794), the mean number of DMFT was 1.30 ± 1.59, the mean number of DMFS was 1.96 ± 3.40, and the filling rate was only 2.35% (20/852). The preva- lence rate and mean DMFT of the first permanent molar caries showed significant difference between different ages and genders (P < 0.05). However, the mean DMFS of the first permanent molar caries only showed significant difference between the various ages (P < 0.05). The prevalence rate of the primary tooth caries was 83.11% (1 491/1 794), the mean number of dmft was 4.82 ± 3.55, the mean number of dmfs was 6.51 ± 5.61, and the filling rate was 12.41% (185/1 491). Caries of primary tooth was the first permanent molar caries risk factor [r = 0.277, OR = 5.736, P = 0.00, 95% CI (4.175, 7.881)]. Significant correlation was found between the caries of primary tooth and first permanent molar (r = 0.274, P < 0.001).

CONCLUSIONCaries status of the first permanent molar among 7- to 9-year-old children in Tangshan city is serious. Caries status of primary tooth may play an important role in predicting the first permanent molar caries in clinic and prevention.

Agricultural Workers' Diseases ; Humans ; Musculoskeletal Diseases

Xanthan gum is a microbial, natural high molecular weight polysaccharide produced by a the bacterium Xanthomonas campestris. Due to its exceptional rheological properties, its numerous areas of application cover a broad range. This review focuses on various aspects of xanthan production, properties, degradation, and application.

Objective To detect the expression of BAT2L protein in developmental brain of rats.Methods Expression,distribution and location of BAT2L protein in developmental brain rats on embryonic day 18,postnatal days 1,7 and 15 and in adult at different time points were detected by Western blotting analysis,immunohistochemistry and immunofluorescence,respectively.Results Western blotting showed that the BAT2L protein expression level was higher in brain of rats on embryonic day 18,postnatal days 1 and 7 than on postnatal day 15 and in brain of adult rats.Immunohistochemistry and immunofluorescence showed that the BAT2L protein was distributed and located in cell membrane and cytoplasm of neurons but not in nuclei and extra-cellular space.Positive neurons were widely distributed in cerebral and cerebellar cortex,hippocampus and cerebral ganglion.The morphology of neurons was significantly different in newborn and adult rats.Positive prominences and branches of certain neurons were found in brain tissues of newborn rats but hardly in those of adult rats.Conclusion BAT2L protein is specifically expressed in cell body,membrane and prominence of neurons in brain of rats.

Objective To investigate the clinical features of primary retroperitoneal fibrosis (RPF), and to find out better method for diagnosis and therapy. Methods Nine patients with primary RPF in Peking Union Medical College Hospital since 1990 to 2003 were analyzed retrospectively. Results All patients had abnormal findings in CT or MRI, and 8 of them had chronic non-specific inflammation of the retroperitoneum in pathology. Six patients had renal involvement and 2 of them had severe renal failure. Eight of the patients had received therapy with corticosteroid or tamoxifene. Conclusions RPF is an uncommon collagen vascular disease characterized by a chronic non-specific inflammation of the retroperitoneum.Because of the atypical manifestations of RPF, awareness of the disease is important.CT and (or) open biopsy remains the gold standard for diagnosis.Management typically includes surgery and drug treatment.Corticosteroid therapy or more recently,tamoxifen has been used successfully. The clinical and radiographic improvement with drug treatment has been seen in several patients and confirmed the diagnosis,thereby early diagnosis and treatment can bring the patient more excellent renal and general outcome.

Objective To evaluate the value of SPECT/CT in differentiating malignancy from benign spinal disease. Methods Fifty-three patients with foci of abnormally increased uptake in the spine detected by 99Tcm-MDP planar whole body bone scan subsequently underwent bone SPECT/CT. The final diagnosis was determined by pathological examination or clinical follow-up ( ≥6 months), which was applied to calculate the diagnostic efficacy of bone SPECT/CT. Results A total of 25 patients were confirmed to have bone malignancy. The diagnostic sensitivity, specificity, accuracy, false positive rate, false negative rate, positive predictive value and negative predictive value for 99Tcm-MDP bone SPECT/CT were 96.00% (24/25), 96.43% (27/28), 96.23% (51/53), 3.57% ( 1/28), 4.00% ( 1/25), 96.00% (24/25) and 96.43% (27/28), respectively. Conclusion 99Tcm-MDP bone SPECT/CT imaging provides good clinical value for the differential diagnosis of spinal diseases.

AlM: To observe the clinic effect of oral mucosa transplantation in the treatment of severe contracted conjunctival sac after ocular prosthesis implantation .
METHODS: Thirty-three cases ( 33 eyes ) with globe disorders and severe contracted conjunctval sac were operated ocular prosthesis implantation firstly, and conjunctival sac plasty using oral mucosa after 6mo.
RESULTS: Thirty - one cases were successful, no complications appeared. One case had primary ptosis and 1 case had recurrent conjunctival sac contracture.
CONCLUSlON:lt is recognised that the methods of oral mucosa transplantation in severe contracted conjunctival sac after ocular prosthesis implantation are effective on those cases.

Objective:To evaluate the effects of the flowable resin used as pit and fissure sealant using different etching adhesive systems.Methods:60 caries-free extracted human premolars were randomly divided into 4 groups(n =1 5)and treated by Gluma, NT and 3M-Z350 flowable resin(group A);Clearifil SE Bond adhesive and 3M-Z350 flowable resin(group B),phosphoric acid etching,3M-Z350 flowable resin and phosphoric acid etching(group C)and 3Mconcise sealant(group D)respectively.After pro-cessing the tooth surface the pit and fissue of 1 0 sample in each group were sealed.The microleakage was measured by 1 % methyl-ene blue staining(n =8).The material-enamel interface was observed by SEM(n =2).The shear bond strength of the column-shaped samples with the diameter and the height of 3 mm(n =5)on the mesial or dental surface was examined by a test machine. The sealant cartridges and flowable resin cartridges with the diameter and height of 4 mm were used for the crushing strength exami-nation(n =1 0).Results:There was no significant difference in the microleakage among the 4 groups.SEMobservation showed that the resin tags of group A were long and dense and the resin tags of group B were short and sparse,bubbles and cracks were found on the local site in group A and B.The resin tags of group C were long and thin,but combined with tooth tightly;the resin tags of group D were short and dense;the penetration was poor at the bottom of the fissures in the 4 groups.The shear bond strength of Group A was the highest(P <0.01 ),that of group C was higher than that of group B and D(P <0.05).There was no significantly difference between group B and D(P >0.05).The compressive strength of flowable resin groups was higher than that of fissure seal-ant group(P <0.05).Conclusion:The shear bond strength and compressive strength of all-etching bonding system combined with flowable resin is superior to that of self-etching bonding system combined with flowable resin and the traditional sealant.Using Prime&Bond NT bond after acid etching may improve the shear bonding strength.

ObjectiveTo investigate the changes of non-linear dynamics characteristics of EEG during picture memory masks, and the application of non-linear dynamic analysis for memory research.MethodsEEGs of 30 healthy old volunteers were recorded under the states of opened eyes and picture memory. Correlation dimension (D2) was calculated for all subjects.ResultsD2 increased significantly during memory tasks compared with the rest state with eyes opened (P<0.05). In different memory tasks, the complexity of mental functions and the regions involved in the memory task were different.ConclusionNon-linear analysis is appropriate for the study of functional changes and working mechanism of brain during memory.

Endostatin is a potent, endogenous inhibitor of angiogenesis, which corresponds to the C-terminal fragment of collagen ⅩⅧ. The human endostatin gene was amplified from a human fetal liver cDNA library by means of PCR and was cloned into pPIC9K vector. Soluble endostatin was superexpressed in Pichia pastoris (50.5mg/L) . The recombinant protein was purified by cation exchange chromatography with the final yield of more than 95%. Western blotting analysis showed positive immunoreactivity to the expressed product. Recombinant endostatin was able to suppress the angiogenesis on the CAMs. Also, the endostatin inhibited specifically of the migration of HMECs stimulated by bFGF, with EC50 being about 0.4 ?g/ml.