AIM: To investigate the amount and patterns of expressing CD69 , IL-4 and IFN-? on TCRV?24 +NKT cells, and compare with that of CD3 +T cells from human peripheral blood in response to in vitro stimulation. METHODS: The whole blood was stained with three-color immunofluorescence directly or after cultured with PDB+ionomycin(Ion) for 6 h, then the mononuclear cells were separated by lysing red blood cells. The expression rates of CD69, IL-4 and IFN-? on TCRV?24 +NKT cells and CD3 +T cells were estimated by flow cytometer. RESULTS: As a proportion of mature T cells, the ratio of TCRV?24 + NKT cells to CD3 +T cells was about(1.34?0.42)%. The expression rates of CD69 on TCRV?24 + NKT cells and CD3 +T cells in response to PDB + Ion for 6 h were (96.71?1.33)% and (98.60?0.47)%, respectively, while the ratio were (11.47?2.86)% and (1.07?0.45)% in the unstimulated group, and there were significant difference between them. The expression rates of IL-4 and IFN-? on TCRV?24 +NKT cells stimulated with PDB+Ion for 6 h were (48.62?2.44)% and (46.65?8.91)%, respectively ,which were significantly higher than that of unstimulated group [(31.57?3.31)%, (13.45?6.29)%] and that of stimulated CD3 +T cells, though the expression rates on stimulated CD3 +T cells were significantly higher than that of unstimulated CD3 +T cells. CONCLUSIONS: There is small amount of NKT cells in adult human peripheral blood. The expression rates of IFN-? and IL-4 on these lymphocytes are higher than CD3 +T cells, suggesting that NKT cells are important immunomodulatory cells in special microvironments.

OBJECTIVE: To investigate the effect of orthodontic traction on the microstructure of dental enamel. METHODS: Forty-eight isolated premolars were randomly divided into 6 groups (=8), including Group A (blank control group), in which the teeth were bonded with the orthodontic brackets without any loading force; Groups B1, B2, and B3 where the teeth were bonded with the orthodontic brackets using clinical adhesives and loaded with 50 g force for 6 months, 200 g force for 6 months, and 200 g force for 1 month, respectively; and Groups C1 and C2, where the teeth were bonded with straight wire brackets using light curing bonding and chemical curing bonding techniques, respectively. All the teeth were embedded with non-decalcified epoxy resin. Scanning electron microscope (SEM), atomic force microscope (AFM), and energy spectrometer (EDS) were used to analyze interface morphology and elemental composition of the teeth sliced with a hard tissue microtome. RESULTS: Compared with those in Group A, the teeth in the other 5 groups showed increased adhesive residue index with microcracks and void structures on the enamel surface under SEM; AFM revealed microcracks on the enamel surface with angles to the grinding direction. A larger loading force on the bracket resulted in more microcracks on the enamel interface. The interface roughness differed significantly between Groups A and C2, and the peak-to-valley distance differed significantly between Groups A, C, and C2. CONCLUSIONS Orthodontic traction can cause changes in the microstructure of normal dental enamel.
Dental Enamel ; Materials Testing ; Orthodontic Brackets ; Resin Cements ; Surface Properties ; Traction

The aquatic grass Zizania latifolia grows symbiotically with the fungus Ustilago esculenta producing swollen structures called Jiaobai, widely cultivated in China. A new disease of Z. latifolia was found in Zhejiang Province, China. Initial lesions appeared on the leaf sheaths or sometimes on the leaves near the leaf sheaths. The lesions extended along the axis of the leaf shoots and formed long brown to dark brown streaks from the leaf sheath to the leaf, causing sheath rot and death of entire leaves on young plants. The pathogen was isolated and identified as the bacterium Pantoea ananatis, based on 16S ribosomal RNA (rRNA) gene sequencing, multilocus sequence analysis (atpD (β-subunit of ATP synthase F1), gyrB (DNA gyrase subunit B), infB (translation initiation factor 2), and rpoB (β‍-subunit of RNA polymerase) genes), and pathogenicity tests. Ultrastructural observations using scanning electron microscopy revealed that the bacterial cells colonized the vascular tissues in leaf sheaths, forming biofilms on the inner surface of vessel walls, and extended between vessel elements via the perforated plates. To achieve efficient detection and diagnosis of P. ananatis, species-specific primer pairs were designed and validated by testing closely related and unrelated species and diseased tissues of Z. latifolia. This is the first report of bacterial sheath rot disease of Z. latifolia caused by P. ananatis in China.
Pantoea/genetics* ; Plant Diseases/microbiology* ; Poaceae/microbiology* ; Virulence