Objective To investigate the biocompatibility and biodegradability of mini-implants of PLA-based composites in experimental animals by histomorphometry, and to study its clinical application in orthodontic treatment. Methods Six adult male Beagle dogs were randomly divided into 3 groups, a total of 72 mini-implants were implanted to the mandibular. Two Beagle dogs were sacrificed at 2 months、4 months and 6 months after surgery. Animals were intramuscularly injected with tetracycline on 14 and 4 days before sacrifice. Mandibular specimens and the surfaces of mini-implants were examined with Cone beam CT, CBCT and Scanning Electronic Microscopy and SEM respectively. Histopathologocal changes were observed with toluidine blue staining and HE staining. Results The results of CBCT assay showed that the mini-implants were gradually radiopacity with the extension of time. SEM assay showed that the morphology of mini-implants surface was significantly changed;micro-implants degradation occured gradually.New bone formation was observed around the micro-implants within 10 days.Toluidine blue staining showed the formation of new bone around the mini-implants. However, the inflamma-tion around the implants was not observed. Conclusion The biocompatibility of biodegradable mini-implant is good. This mini-implant is biodegradable in vivo and can promote the formation of the surrounding bone tissue.

Objective To isolate and purify VacA protein secreted by Helicobacter pylori or recombinant VacA , and to investigate the effect of VacA-induced cell vacuolar change and apoptosis .Methods VacA proteins were separated and pu-rified from the culture supernatant of H.pylori ( ATCC26695 ) or from the split products of genetically engineered bacteria (pQE30-VacA-E.coli M15) expressing recombinant VacA.The VacA protein obtained was acidified and then incubated with AGS cells for 24 h at different final concentrations of 5 and 10 ng/ml before the vacuolar change and apoptosis of AGS cells were detected via microscopy and flow cytometry assay , respectively .Results H.pylori-secreted VacA and recombi-nant VacA were successfully separated and purified .The H.pylori-secreted VacA significantly induced the vacuolar change and apoptosis of AGS cells (P<0.01) while the recombinant VacA did not.Conclusion H.pylori-secreted VacA protein can effectively induce cell vacuolar change and apoptosis, but recombinant VacA can not, suggesting that the purified VacA protein secreted by H.pylori can be used to explore VacA-induced pathogenesis.

Objective To investigate the methylation status of Zonula occludens-1(ZO-1)gene promoter and discuss its role in the pathogenesis and progression of acute leukemia(AL)as a general gene marker.Methods The methylation pattern in promoter region of ZO-1 gene was detected with methylation specific PCR in AL cell lines HL60.Molt4 and NK92 as well as in 121 clinical bone marrow samples including 81 cases of AL and 40 non malignant cases.Resuits The promoter region of ZO-1 gene was completely methyrlated in HL60.Molt4 and NK92 cells:but it was unmethylated in 40 non malignant bone marrow samples.The total methylation frequency of ZO-1 gene promoter region in 81 cases of AL was 60.49%(49/81),there was significant statistic difference among the relapsed AL group(92.86%, 13/14),the newly diagnosed AL group(65.85%,27/41)and the complete remission group(34.62%, 9/26).but no difference between the cases with acute myelocytic leukemia and acute lymphocytic leukemia. Conclusion The hypermethylated status of ZO-1 gene promoter region was specifically detected in human AL,it was closely correlated with the pathogenesis and progression of the disease and will become a general clinical molecular marker of leukemia.

Objective To investigate the correlation between Helicobacter pylori (HP) infection-associated gastritis and the ap-optotic genes in gastric mucosa .Methods Forty-five patients with chronic gastritis were registrated in our study from November 2013 to December 2014 .HP infection status in the patients was detected by using urease test and 13C-urea breath test .The degree of gastritis in the gastric mucosa with HP infection was confirmed via histopathology .qRT-PCR was used to measure the mRNA ex-pressions of Bax ,Bak and Bcl-2 in the gastric mucosa with HP infection and matched normal gastric mucosa .Person analysis was used to assess the correlation between the HP infection-associated gastritis and the mRNA expressions of Bax ,Bak and Bcl-2 in the gastric mucosa .Results Forty-five patients with HP infection in antrum and 45 patients (100% ) with chronic antrum gastritis were identified ,including 28 patients (62 .2% ) with light gastritis ,16 patients (35 .6% ) with moderate gastritis ,1 patient (2 .0% ) with severe gastritis .9 patients (20 .0% )with metaplasia ,5 patients(11 .1% ) with low grade intraepithelial neoplasms .The urease tests were negative in the gastric body of 45 patients ,6 patients (13 .3% )were mild chronic gastritis in the body ;Patient with meta-plasia and intrapithelial gastritis was not found .The Bax expression in the HP-infected gastric mucosa was markedly increased when compared with the normal gastric mucosa (P< 0 .01) ,and positively correlated with the degree of gastritis (P< 0 .01) , whereas the expressions of Bak and Bcl-2 have no significantly deferences bttween two groups(P>0 .05) .Conclusion HP infec-tion-associated gastritis positively correlated with the expressions of apoptotic genes in gastric mucosa ,suggesting that HP infection might result in increasing the Bax expression and further enhancing the cell apoptosis .

Objective To investigate the clinical characteristics of the human Adenovirus (HAdv) infections in allogeneic hematopoietic stem cell transplantation ( allo-HSCT) patients and explore the clinical significance of HAdv monitoring .Methods A total of 845 cases underwent allo-HSCT were included retrospectively in Perking University People′s Hospital from October 2012 to August 2014.Peripheral blood HAdv load were monitored twice weekly within 100 days after allo-HSCT, or whenever necessary quantitatively by real-time PCR. Meanwhile, other clinical samples such as stool , urine, and bronchoalveolar lavage fluid ( BLAF ) were also detected qualitatively whenever necessary .The follow-up period was at least six months after allo-HSCT.All clinical data were collected and analyzed .Results The total positive rate of HAdv was 3.4% ( 29/845 ) .The incidence of HAdv infection was higher in children [3.8%(6/155), <18y] than that of adults [3.3%(23/690),≥18y].HAdv infection diagnosed within 100 days after allo-HSCT accounted for 72.4%(21/29) of the total number of positive cases .There were 19 cases detected positive in peripheral blood , 16 cases in stool , 9 cases in urine , and 1 cases in BLAF , respectively.One patient was positive in peripheral blood , stool and urine.The overall median time of HAdv was 69 (13-189) d.The median time was 56 (53 -144) d in stool ,which was earlier than that of in peripheral blood , urine and stool.Among 29 cases of HAdv positive patients , 17 patients were coinfected with Cytomegalovirus(CMV) and 11 casess with Epstein-Barr virus(EBV).Twenty-five cases of HAdv were diagnosed with acute graft-versus-host disease(aGVHD) before HAdv infection, and 4 cases were diagnosed with chronic graft-versus-host disease ( cGVHD ) . The most common clinical manifestation was HAdv enteritis (14 cases), followed by hemorrhagic cystitis (7 cases).Two cases complicated with multiple organ injury ( >2 ) clinically, 1 cases with pneumonia.There were 8 cases of death at the end of follow-up.Conclusions HAdv is an important pathogen causing infection in patients after allo-HSCT. The infenction is characterized with multiple organ involvement .CMV and EBV coinfection is common .HAdv monitoring was of great significance in allo-HSCT patients.

Nonspecific building related illnesses (NBRI) are an array of diverse symptoms related to working in particular buildings. There are numerous contributing factors, including basic factors (temperature, humidity and ventilation) as well as chemicals, dust, microorganisms, and psychosocial factors. At the individual level, taking a careful history is the essential first step. After ruling out other diseases, clinicians can start the symptomatic treatment for NBRI. If a relationship to the building is suspected, a walk through evaluation is very helpful. At the group level, standardized questionnaires and investigations of the building environment can be applied simultaneously. If the prevalence of symptoms are greater than that of general population, appropriate interventions have to be provided for prevention and group health care. In both approaches, it is essential to periodically follow up with symptomatic patients and work environments after an intervention. For the management of NBRI, taking care of the patient's symptoms and maintaining a good indoor environment are important. To achieve this goal, cooperation among workers, building managers, employers and occupational health staff is crucial.
Air Pollution, Indoor ; Delivery of Health Care ; Dust ; Humans ; Humidity ; Occupational Health ; Prevalence ; Questionnaires ; Resin Cements

OBJECTIVES: We investigated the status of the preplacement medical examination after the revision of the industrial safety and health law on Oct. 7, 2005 by the Ministry of Labor. METHODS: Preplacement medical certificates of 6,507 recruits issued by two hospitals in Busan, Kyeongnam Province from Jan. 1 to Dec. 31, 2006 were reviewed. Telephone interviews were performed to the recruits with disease and self-reported questionnaires were administrated to health and safety personnel from May 1 to Sep. 30, 2007. RESULTS: Interviews were conducted with 185(56.1%) recruits with disease, 51(27.4%) of whom were rejected for employment due to the preplacement medical certificate. The questionnaire survey for the health and safety personnel revealed that 39(22.9%) personnel were unaware of the annulment of the preemployment medical examination. Eighty(48.8%) of the health and safety personnel answered that they performed a preplacement medical examination after employment, and 63(37.3%) made a practical application of the workers' placement. The recruits with chronic conditions were refused employment: 20 (11.8%) due to hypertension, 21(12.4%) diabetes mellitus and 22(13.0%) hyperlipidemia. The recruits with work-related diseases were also refused employments: 76(44.4%) due to lumbar spine abnormality and 75(43.8%) hearing loss. CONCLUSIONS: Despite the annulment of the pre-employment medical examination, a preplacement medical examination was often used to discriminate among healthy and diseased recruits. Employers must respect the law for the point of time of the preplacement medical examination and the payment of cost. The government should publicize the revision of the objectives of the law. We suggest that health professionals elucidate the job fitness through the development of the assessment tools and maintain the confidentiality of recruits.
Confidentiality ; Diabetes Mellitus ; Employment ; Health Occupations ; Hearing ; Hyperlipidemias ; Hypertension ; Interviews as Topic ; Jurisprudence ; Questionnaires ; Spine

Objective:To estimate the physical dose of an over exposed person working for industrial radiography.Methods:The main exposure parameters were obtained. The exposure duration was 8 min. The exposure pattern was external exposure by isotropic point radioactive source. The radioactive activity was 2.183 TBq. In the present calculation, the Chinese reference adult voxel phantom was used, and the Monte Carlo simulation was performed using the program based on the secondary development of Geant4 to obtain the absorbed dose of each part of the victim.Results:The dose distribution in the victim′s hands was obtained. The doses to most areas of the palm were 2-10 Gy, and the doses to the fingers were 10-20 Gy. The equivalent doses to 23 tissues or organs of the exposed person were estimated to be in the range of 0.012-0.207 Gy.Conclusions:The physical dose estimation method could evaluate rapidly the local dose distribution of the victim′s key exposed body parts, and thus provide an important reference for medical treatment.

Objective:To estimate the mental health status and personality traits of the nuclear radiation emergency rescuers, allowing to provide reference basis for improving their mental health.Methods:Totally 52 nuclear radiation emergency rescuers were selected as the subjects. The symptom checklist 90 (SCL-90) and Cattell′s 16 personality factor scale (16PF) were used to assess their mental health status and personality traits. The results obtained from the survey of these rescuers were compared with those obtained using Students′ t-test, One-Way ANOVA and Pearson correlation analysis. Results:The average scores of multiple factors and positive items of the SCL-90 were significantly lower in the rescuers than in the norm ( t=-4.77 to -2.04, P<0.05), and the positive rate was 21.15%. The symptom checklist 90 subscales such as somatization, obsessive-compulsive and depression were found in the rescuers. Rescuers received high scores in the following components among the 16 factors of Cattell: less intelligent-more intelligent, emotionally stable. Rescuers also received low scores in the following components among the 16 factors of Cattell: tough-minded-tender-minded, trusting-suspicious. Life satisfaction, educational degree and Cattell′s 16 PF were significantly associated with the factors of SCL-90( r=-0.569 to 0.627, P<0.05). Conclusions:The rescuers are better than ordinary Chinese people in psychological health. Mental health-related factors such as literacy, life satisfaction, and personality traits should be taken into account when selecting team members and conducting psychological interventions.

Medical rescue bases for nuclear or radiological emergencies are mostly composed of institutions that have obtained the qualification of radiological health technical service (Class A) or the qualification of radiation-induced disease diagnosis. Institutions of radiological health have accumulated the technical capabilities of radiation monitoring, contamination detection, dose estimation, and health effects evaluation in their daily work, which can play an important role in the response to nuclear or radiological emergencies and realize the “combination of non-emergency and emergency use” in capacity building. It is suggested that institutions of radiological health at all levels should continue to take advantage of their strengths, improve their capabilities through participating in radiation monitoring projects, and actively participate in the assessment of assay capabilities of institutions of radiological health, so as to provide personnel and technical reserves for the health response to nuclear or radiological emergencies.