The effect of saliva contamination on the shear bond strength of orthodontic brackets, at various stages of the bonding procedure using a new self-etch primer was studied. The samples were divided into 4 groups according to 4 different enamel surface conditions: Group A: dry; Group B: saliva contamination before priming; Group C: saliva contamination after priming, and Group D: saliva contamination before and after priming. Stainless steel brackets were bonded in each test group with a light-cured composite resin (TransbondXT 3M). The shear bond strength was determined in the first 30 min after bonding. The analysis of variance indicated that the shear bond strengths of the 4 groups were significantly different (F = 11.89, P < 0.05). Tukey HSD tests indicated that contamination both before and after the application of the acid-etch primer resulted in a significantly lower (=4.6 +/- 1.7 MPa) shear bond strength than either the control group (=8. 8 +/- 1.9 MPa) or the groups where contamination occurred either before ( = 7.9 +/- 2.0 MPa) or after (= 6. 9 +/- 1.5 MPa) the application of the primer. It was concluded that the new acid-etch primer could maintain adequate shear bond strength if contamination occurred either before or after the application of the primer. On the other hand, contamination both before and after the application of the primer could significantly reduce the shear bond strength of orthodontic brackets.
Acid Etching, Dental ; Orthodontic Brackets ; Saliva ; Shear Strength

Objective:To observe HSP70 expression during experimental tooth movement in rats.Methods:Orthodontic appliance was placed between the maxillary right first molar and maxillary central incisors of 30 adult SD rats.The rats were killed at 1,3,5,7,14 d after orthodontic force application,samples of experimental teeth with periodontal tissue were prepared for immunohistochemical examination of HSP70 expression.Result:Strong expression of HSP 70 in periodontal ligment was observed at 1 and 3 d after orthodontic force application,positive at 5 d and weak positive at 7 and 14 d.Conclusion:HSP 70 is expressed in periodontal ligment at different levels in different stages during orthodontic tooth movement.

AIM:To investigate the differences of clinical signs and pathological structure of unilateral nasal pterygium and unilateral double pterygium.METHODS:Retrospective study.Totally 11 unilateral nasal pterygium and 11 unilateral double pterygium were collected to observe the size of the tissue area, the classification of blood vessels, the transparency and the break-up time of tear film.The 11 surgically excised double pterygia (11 eyes) and 6 samples of normal conjunctiva were collected for the study.With 40g/L paraformaldehyde fixation, paraffin sections were stained with Haematoxylin-Eosin, to observe the differences with nasal and temporal pathology under light microscope.RESULTS:In unilateral double pterygium, the tear break-up time was significantly shorter than that of unilateral nasal pterygium (t=3.410, P=0.003).In unilateral nasal pterygium, there was a significant negative correlation between tear film break-up time and tissue size(r=-0.927, P<0.01) and transparency(r=-0.764,P<0.01).In unilateral double pterygium, the tear break-up time was significantly negatively correlated with the growth time (r=-0.661, P<0.05), tissue size (r=-0.775, P<0.01) and transparency (r=-0.671,P<0.05).In unilateral double pterygium, compared with the temporal side, the quantity of the layers of corneal epithelial cells (t=-7.351, P<0.05), vessels (t=-7.400, P<0.05) and inflammatory cells (t=-7.481, P<0.05) increased.CONCLUSION:Compared with unilateral nasal pterygium, the tear film break-up time of unilateral double pterygium was poor.In unilateral double pterygium, with high activity, the degree of proliferation of squamous epithelium, hyperplasia and inflammatory reaction are significantly higher than those of the temporal side.

Osteoclastic bone resorption and osteoblastic bone formation are coordinated as a coupled mechanism to effect the development of bone and to maintain bone homeostasis. Recently reported Eph/ephrin bidirectional signaling between osteoclasts and osteoblasts plays a pivol role in bone homeostasis and casts new light on coupling of bone resorption and bone formation, which is gaining more and more attention in researches of bone biology and bone diseases. The present article aims to address the researches on the Eph/ephrin bidirectional signaling between osteoblasts and osteoclasts with molecular constitution, mechanism of the signal transduction, biological significance and so on.

Humans ; Proteomics ; methods ; Silicosis ; metabolism ; Specimen Handling ; methods

Objective To observe the efficacy and side effects of Jianpi Qutan Decoction combined with Quetiapine in the treatment negative symptoms of schizophrenia.Methods 60 inpatients with schizophrenia were randomly divided into two groups,with one group treated with Jianpi Qutan Decoction combined Quetiapine and the other group treated with Quetiapine.Effects and side effects were assessed with the Positive and Negative Syndrome Scale (PANSS) and Treatment Emergent Symptoms Scale (TESS) respectively 1,4 and 8 weeks before and after the treatment.Results There was no significant difference in the overall efficacy between the two groups,but the improvement of the negative symptoms and illness provocation was significantly better in the treatment group than that in the control group respectively (P＜0.05).Moreover,the adverse reaction was milder in the treatment group.Conclusion It is suggested Jianpi Qutan Decoction in combination with typical antipsychotics is effective and safe in treating negative symptoms in schizophrenia patients.

Objective To evaluate the skills in using inhalers among the asthmatic patients who visited the out-patient clinic and whether or not the nursing intervention could further improve the efficacy of the drug delivery device. Methods 321 asthmatic patients who had visited the clinic and prescribed inhalers from April to December 2009 were investigated of the basic status, former medication history and skills in using metered dose inhaler (MDI) and dry powder inhaler (DPI). Nursing intervention had been carried out and the results were analyzed. Results Subjects belonging to different educational level groups were significantly different in mastering skills using MDI and DPI after reading instructions. There also existed significant difference between MDI and DPI users. Among patients who had already used inhalers, there was significant difference between subjects who had received instruction from medical personnel and subjects who had only read paper directions. Nursing intervention could significantly improve the skills in handling the device. Conclusions Proper skills in using inhalers could not be possessed just by reading paper directions. Instructions or even multimedia presentation from medical personnel are vital for asthmatic patients to master the skills in using MDI and DPI.

Objective To learn the status quo of core competency of registered nurses in tertiary level first-class hospitals in Liaoning Province and compare the level and characteristics of core competency of registered nurses in different working years in order to supply evidence to establish contrapuntal training protocol.Methods "The Competency Inventory for Registered Nurse scale"(CIRN,by LIU Ming)was distributed to investigate the core competency of registered nurses,the data underwent analysis.Results The overall score of core competency level was (174.11±31.89),the score of the nurses with 16～20 years of working experience was the highest,while the score of nurses working for 1～5 years was the lowest.The core competency varied with working years,evident difference existed in different dimensions and total scores.Conclusions The overall core competency is at the upper middle level for registered nurses from five tertiary level first-class hospitals in Liaoning Province.They are competent enough to provide health care.With the increasing length of working time,nurses' core competency level will strengthen gradually.

Objective To study the relationship between the prevalence of thyroid dysfunction and components of metabolic syndrome.Methods A total of 10 461 working and retired employees aged 20 to 90 years in a Petrochemical Corporation in Ningbo were included.Body mass index ( BMI),waist circumference,blood pressure,fasting blood glucose,blood lipid profile,serum thyroid-stimulating hormone (TSH),free thyroxine ( FT4 ),and free triiodothyronine (FT3 ) were measured in all subjects. Metabolic syndrome was diagnosed according to the International Diabetes Federation(IDF) criteria.Results ( 1 ) The prevalences of metabolic syndrome and overall thyroid dysfunction were 10.2％ and 4.6％,respectively. ( 2 ) 18.1％ petrochemical employees had abdominal obesity with at least one component of metabolic syndrome.( 3 ) There was no significant difference in the prevalence of metabolic syndrome among the groups with lowered,normal,and elevated TSH. (4) Logistic regression analysis revealed that lowered high density lipoprotein cholesterol ( HDL-C ) was associated with lowered TSH ( OR =0.313,95％ CI 0.184-0.530 ),and raised triglyceride was associated with elevated TSH ( OR =0.767,95％ CI 0.595-0.991 ). ( 5 ) There were significant associations between serum TSH levels and lipid parameters such as total cholesterol in males,triglyceride and low density lipoprotein cholesterol in females,and HDL-C in both genders.Conclusion The prevalence of thyroid dysfunction was not associated with central obesity,hypertension,and hyperglycemia.Lipid disorder was correlated with serum TSH levels.

Purpose To investigate the clinicopathologic features of calcifying aponeurotic fibroma (CAF). Methods The clinical and pathologic profiles of 6 cases of CAF were retrospectively analyzed. Results CAF appeared a firm, painless and slowly growing mass with a predilection for the distal portions of the extremities in young children and adolescents. Microscopically, the tumor consis-ted mainly of benign appearing spindle cells, chondroid cells and calcific debris. Immunohistochemically, the tumor cells were positive for vimentin, HHF-35, S-100, Calponin and CD68. Conclusion CAF is a rare, locally aggressive fibroblastic lesion. It can make an accurate diagnosis by integrating the clinical location with histopathological features. Repeated minor trauma to the extremities and some embryologic cell nests maybe its pathogenesis.