Cytocompatibility of nanophase hydroxyapatite ceramics / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the cytocompatibility of nanophase hydroxyapatite ceramics in vitro.</p><p><b>METHODS</b>Hydroxyapatite (HA) was prepared via wet method. The grain size of the hydroxyapatite in the study was determined by scanning electron microscope and atomic force microscope with image analysis software. Primary osteoblast culture was established from rat calvaria. Cell adherence and proliferation on nanophase hydroxyapatite ceramics and conventional hydroxyapatite ceramics were examined at 1, 3, 5, 7 days. Morphology of the cells was observed by microscope.</p><p><b>RESULTS</b>The average grain size of the nanophase and conventional HA was 55 nm and 780 nm, respectively. Throughout 7 days period, osteoblast proliferation on the HA was similar to that on tissue culture borosilicate glass controls, osteoblasts could attach, spread and proliferate on HA. However, compared to conventional ceramics, osteoblast proliferation on nanophase HA was significantly better after 1, 3, 5 and 7 days.</p><p><b>CONCLUSION</b>Cytocompatibility of nanophase HA was significantly better than conventional ceramics.</p>

Biomechanical study of open bite treatment with tip forward bend / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To verify whether it is effective to treat open bite cases with tip-forward bend.</p><p><b>METHODS</b>Three-dimensional finite element (TDFE) models of the lower left central incisor and first molar were set up by means of CT. Stress distribution in root, PDL and alveolar bone, and the tendency of the tooth movement were obtained by calculation under different orthodontic forces.</p><p><b>RESULTS</b>(1) The molar model revealed that the tensile stress concentration was at the distal cervix and the compressive stress concentration at mesial cervix. (2) The incisor model showed that the tensile stress was concentrated at apical tip and the compressive stress concentration was at the lingual side of the cervix. (3) The incisor had the tendency to elongate and move lingually. The molar tended to tip mesially and buccally.</p><p><b>CONCLUSIONS</b>Arch wire with tip forward bend depends on the elongation and lingual movement of anterior teeth to treat open bite, but the anchorage molar will incline mesially further, which is not consistent with the mechanism to treat open bite.</p>

Effects of Mycobacterium tuberculosis infection on the transcriptional expression of human macrophage gene encoding ion channels and related regulatory elements / 生理学报

Expression microarray was employed in this study to investigate whether the ion channels and their regulatory elements encoding genes participate in the immune response to Mycobacterium tuberculosis infection. The results of a virulent strain were compared with those of the clinically isolated strains. The data demonstrate that K(+), Na(+), Ca(2+) and Cl(-) channels and their regulatory elements, such as the G protein, receptor and second messenger, protein kinase and protein phosphatase were involved in the immune reaction. The clinical strain affected more types of ion channels and respective regulatory elements. The data provides clues for further scrutiny into the role of ion channels and related elements in the interaction between Mycobacterium tuberculosis and host macrophage.

Imaging diagnosis of lung lacerating injury / 中华放射学杂志

Objective To investigate the imaging findings of the lacerating injury of the lung. Methods Ten patients of lung lacerating injury were examined by X-ray and CT within 1—5 h after injury. X-ray(2—5 times)and CT(3—5 times)examinations were repeated for 7 patients.Results The lung lacerating injury involved 10 sides and 14 lung lobes(21 lesions in total)in the 10 cases,among which 1 case involved the right upper lobe with 1 lesion,2 cases in the right lower lobe with 2 lesions,1 case in the right upper and lower lobes with 2 lesions for each lobe,3 cases in the left lower lobe with 9 lesions,and 3 cases in both the left upper and the lower lobes with 7 lesions.The X-ray findings were cavity-like shadows with smooth margin in 9 lesions(9/21),and patchy shadows of fogging margin in 12 lesions(12/21).The CT imaging findings included 6 pulmonary hematomas(6/21),and 15 cavitary lesions with air-fluid levels (15/21).In the 15 cavitary lesions,CT revealed 14 single cavities and 2 small cavities within a big cavity. On dynamic follow-up observation,the cavity was the biggest in 1—5 h after injury,but the hematoma was the biggest in 2—3 days after injury.Hematomas tended to absorb slower than the cavities.After 16— 32 days,all lesions revolved into small patchy or stripe-like shadows with slightly increased density. Conclusion Cavitary lesion with air-fluid level is the characteristic imaging finding of lung lacerating injury.CT surpasses X-ray plain film in revealing the details of lung lacerating injury.