BACKGROUND: Genetic factors account for the majority of differences in skin color and hair morphology across human populations. Although many studies have been conducted to examine differences in skin color across populations, few studies have examined differences in hair morphology. OBJECTIVE: To investigate changing of integral hair lipids after ultraviolet (UV) irradiation in three human ethnic groups. METHODS: We studied the UV irradiation induced hair damage in hairs of three human populations. UV irradiation had been performed with self-manufactured phototherapy system. Damaged hair samples were prepared at 12 and 48 hours after UVA (20 J/sec) and UVB (8 J/sec) irradiation. We evaluated the changes of hair lipid using scanning electron microscopy (SEM), transmission electron microscopy (TEM), lipid TEM and HP-TLC. After UV irradiation, hair surface damage was shown. RESULTS: African hair showed more severe damage on hair surface than others. The lipid compositions across human populations were similar, but Asian hair had more integral hair lipids than other groups as a whole. Especially, free fatty acid contents were higher than other lipids. After UV irradiation, lipid contents were decreased. These patterns were shown in all human populations. Asian hair has more integral hair lipid than European or African hair. After UV irradiation, European and African hair samples exhibited more damage because they have less integral hair lipids. However, Asian hair samples have less damage. CONCLUSION: We conclude that integral hair lipid may protect the hair against the UV light.
Asian Continental Ancestry Group ; Ethnic Groups ; Hair ; Humans ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Phototherapy ; Skin ; Ultraviolet Rays ; Viola

PURPOSE: In this study, three bioceramic materials, [IPS Empress CAD (Ivoclar), IPS e.max CAD (Ivoclar), and Lava Ultimate CAD (3M ESPE)] were treated with three commercial mouthrinses [Listerine, Tantum Verde, and Klorhex]; and changes in colour reflectance and surface roughness values were then quantitatively assessed. MATERIALS AND METHODS: One hundred and twenty ceramic samples, with dimensions of 2 × 12 × 14 mm, were prepared and divided into nine sample groups, except three control samples. The samples were immersed in the mouthrinse solutions for 120 hrs, and changes in colour reflectance and surface roughness values were measured by UV light spectrophotometry (Vita Easyshade; VITA Zahnfabrik) and by profilometer device (MitutoyoSurftest SJ-301), respectively. The change of surface roughness was inspected by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). RESULTS: There was a positive correlation between the ΔE and increase in the surface roughness. Two of the ceramic materials, IPS Empress and Lava Ultimate, were affected significantly by the treatment of the mouthrinse solutions (P<.05). The most affecting solution was Tantum Verde and the most affected material was Lava Ultimate. As expected, the most resistant material to ΔE and chemical corrosion was IPS e max CAD among the materials used. CONCLUSION: This work implied that mouthrinse with lower alcohol content had less deteriorating effect on colour and on the surface morphology of the bioceramic materials.
Benzydamine ; Ceramics ; Corrosion ; Microscopy, Atomic Force ; Microscopy, Electron, Scanning ; Refractometry ; Spectrophotometry ; Ultraviolet Rays

OBJECTIVETo explore the effect of different functional groups on self-assembled monolayers on the biological characteristics of rabbit skeletal muscle cells in vitro.

METHODSRabbit skeletal muscle cells were cultured on self-assembled monolayers of gold on which different terminal chemical groups including methyl groups (-CH(3)), amino(-NH(2)), hydroxyl(-OH) and carboxyl (-COOH ) were anchored with self-assembled methods. Contact angle measurements and atomic force microscopy were employed to confirm the similar density of different functional groups occupation. Fluorescence microscopy, MTT assay, flow cytometry, and scanning electron microscopy (SEM) were used to analyze the morphological and biological alterations of the cells.

RESULTSSEM results revealed that the chemical groups on the surface of the monolayer modulated the structure of skeletal muscle cells and the cell morphology. Skeletal muscle cells cultured on the monolayer with -CH3 exhibited the smallest contact area with a spherical morphology, while the cells on the monolayers with -NH(2), -OH and -COOH showed much larger contact area and flatter morphology. The functional groups -NH(2) and -COOH obviously promoted cell adhesion and proliferation, while -CH(3) group produced significantly greater toxicity than -NH(2), -OH and -COOH groups to inhibit the cell growth and adhesion and promote cell death. Cell attachment and growth was enhanced, in the order the magnitude of the effect, by -NH(2)>-COOH>-OH>-CH(3), and the toxicity decreased in the order of -NH(2)>-COOH>-OH>-CH(3).

CONCLUSIONThe terminal chemical groups can obviously affect the phenotype of skeletal muscle cells in vitro, and this finding provides a theoretical basis for surface design of biomaterials.

Animals ; Cell Adhesion ; Cell Proliferation ; Cells, Cultured ; Microscopy, Atomic Force ; Microscopy, Electron, Scanning ; Microscopy, Fluorescence ; Muscle Fibers, Skeletal ; cytology ; Rabbits

To investigate the difference of texture exhibited on interproximal enamel surface with each different stripping method and the susceptibility of proximal enamel to demineralization after stripping and the application of a topical fluoride gel and sealant, one hundred human premolars, which were previously extracted for orthodontic reasons were evaluated by means of Scanning electron microscopy and laser fluorescence. The results were as follows : 1. No matter what the initial stripping instrument was the furrows that resulted from all the stripping methods were not completely removed by careful polishing. 2. Among the enamel surfaces that were treated with three different initial abrasive instruments, followed by the same polishing method (Sof-Lex(R)disks), the enamel surfaces that were treated with 700 crosscut carbide bur showed the smoothest surfaces. 3. The stripped teeth, no matter what the initial stripping instrument was, were less resistant to initial demineralization than untreated teeth. But no difference in caries susceptibility according to differently stripped methods was found (p<0.001). 4. Teeth treated with APF-gel or sealant were more resistant to demineralization than those treated without other treatment after stripping (p<0.001). 5. Comparing groups treated with APF-gel to groups treated with sealant, the former was more resistant to demineralization than the latter (p<0.05). In conclusion, enamel surfaces that were stripped interproximally were less resistant to demineralization even though various attempts were made to produce smooth, self-cleaning enamel surfaces. Therefore, additional treatment-sealant or calcifying/ fluoridating solution to the stripped enamel surfaces is recommended.
Bicuspid ; Dental Enamel* ; Fluorescence ; Fluorides ; Humans ; Microscopy, Electron, Scanning ; Tooth*

OBJECTIVES: The purpose of the present study was to evaluate the whitening effect, morphological and structural changes, and remineralization of the enamel induced by 3 combined agents: amorphous calcium phosphate (ACP), hydroxyapatite (HA), and tetrasodium pyrophosphate (TSP). METHODS: The study was performed on 90 bovine enamel slabs, which were divided into the 6 groups: negative control-distilled water (Group 1); positive control-opalescence F (Group 2); 10% mixed agent (Group 3); 25% mixed agent (Group 4); 50% mixed agent (Group 5); and 100% mixed agent (Group 6). Changes in the shade of the enamel slabs were evaluated using Shade Eye-NCC. Morphological changes were assessed by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) was used to determine the remineralizing effect of the three agents on enamel slabs. RESULTS: The change in shade of the enamel (ad*) was noted to increase significantly with increase in whitening frequency in all groups. The value of Δn* was significantly greater in all groups except for the negative control group (P<0.001). SEM revealed that the control group, Group 5, and Group 6 had similar morphologies. The fluorescence lesion areas in the 4 mixture-treated group were significantly smaller than those in the positive control group (P<0.001). CONCLUSIONS: These results showed that the mixture of ACP, HA, and TSP was highly effective for bovine enamel whitening and acted by inducing the remineralization of enamel. CLINICAL SIGNIFICANCE: We evaluated the applicability of a new mixture containing ACP, HA, and TSP. This mixture would be highly useful in aesthetic dentistry because of its whitening efficiency, which does not compromise the enamel's integrity.
Calcium* ; Dental Enamel* ; Dentistry ; Durapatite* ; Fluorescence ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Water

BACKGROUND: The aim of this study is to verify the feasibility of using silk fibroin (SF) as a potential membrane for guided bone regeneration (GBR). METHODS: Various cellular responses (i.e., cell attachment, viability, and proliferation) of osteoblast-like MG63 cells cultured on an SF membrane were quantified. After culturing on an SF membrane for 1, 5, and 7 days, the attachment and surface morphology of MG63 cells were examined by optical and scanning electron microscopy (SEM), cell viability was determined using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation was quantified using 4',6-diamidino-2-phenylindole (DAPI) fluorescence staining. RESULTS: Optical microscopy revealed that MG63 cells cultured on the SF membrane proliferated over the 7-day observation period. The viability of cells cultured on SF membranes (SF group) and on control surfaces (control group) increased over time (P < 0.05); however, at respective time points, cell viability was not significantly different between the two groups (P > 0.05). In contrast, cell proliferation was significantly higher in the SF membrane group than in the control group at 7 days (P < 0.05). CONCLUSIONS: These results suggest that silk fibroin is a biocompatible material that could be used as a suitable alternative barrier membrane for GBR.
Bone Regeneration* ; Cell Adhesion ; Cell Proliferation ; Cell Survival ; Fibroins* ; Fluorescence ; Membranes* ; Microscopy ; Microscopy, Electron, Scanning ; Osteoblasts ; Silk*

OBJECTIVETo study the influence of ultraviolet (UV) irradiation on physical and chemical properties of sandblasted and acid-etched (SA) titanium surface and their ability to adsorb human fibronectin (HFn).

METHODSSA and UV-SA surfaces were separately prepared. Surface morphology, roughness, elemental composition, wettability and HFn adsorption assay were performed for comparative analysis of these two surfaces.

RESULTSSA and UV-SA surface had a similar morphology with multi-holes, and average roughness. UV-SA surface had a lower C content (22.83%) and higher O content (51.20%) and presented hydrophilicity, while SA surface showed hydrophobicity. But the quantity of adsorbed HFn on SA surface at 10 min assay point [(0.41 ± 0.07) µg] was statistically higher than that on UV-SA surface [(0.26 ± 0.08) µg](P = 0.007).

CONCLUSIONSUV irradiation would not change the morphology and roughness of SA surface. However, it could reduce the hydrocarbon and increase the hydroxyl groups, and the absorption of HFn on UV-SA surface at 10 min assay point was statistically lower than that on SA surface. Therefore, the in-vitro bioactivity of UV-SA surface was not as good as that of SA surface.

Adsorption ; Fibronectins ; chemistry ; Humans ; Microscopy, Electron, Scanning ; Surface Properties ; Titanium ; Ultraviolet Rays ; Wettability

PURPOSE: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of TiO2 blasting implant surface. MATERIALS AND METHODS: Ten TiO2 blasting implant were used in this experiment. One implant was control group, and nine TiO2 blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. RESULTS: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the TiO2 blasting implant surface in SEM study while 180 mJ/pulse group altered the TiO2 blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. CONCLUSION: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.
Freezing ; Microscopy, Electron, Scanning

Megaselia scalaris (Loew) (Diptera: Phoridae) is a cosmopolitan scuttle fly of medical and forensic importance. This species is generally small, humpbacked and is a prominent decomposer of corpses indoors. Taxonomically, adult sexes can be distinguished based on the characteristics of the terminal segments of the abdomen. In this report, the terminalia of adult male and female M. scalaris were examined using scanning electron microscope (SEM). The terminal segment of an adult female is less complex compared to male, consisting of an ovipositor and cerci. In male, the hypopygium consists of epandrium, hypandrium, anal tube and penis complex. A pair of long and feathered setae was attached to the tip of the anal tube and tapered. The application of SEM to identify this species isuseful and can be expanded to other species in this fly group.
Microscopy, Electron, Scanning

PURPOSE: This study was carried out to clarify the histological characteristics of the interface of the corneal stroma and Descemet's membrane of the human eye. METHODS: Nighteen donor eyes without corneal pathology were examined by scanning and transmission electron microscopy. The Descemet's membrane including the corneal endothelium was cheked for scanning electron microscopy. The junctional characteristics of the posterior corneal stroma and Descemet's membrane was examined by transmission electron microscopy. RESULTS: The scanning electron microscopy showed that collagen sheet faced each other at the right angle near the Descemet's membrane and penetrated the Descemet's membrane with the irregular arrangement. The transmission electron microscopy showed that the electron-dense collagen filaments extended to the posterior stroma from Descemet's membrane. The arrangement of electron-dense collagen filaments paralleled with the arrangement of the collagen fibrils of the posterior stroma. CONCLUSIONS: The interface of the corneal stroma and Descemet's membrane was composed of two-typed extracellular materials without the intercellular specificatons.
Collagen ; Corneal Stroma* ; Descemet Membrane* ; Endothelium, Corneal ; Humans ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Microscopy, Electron, Transmission ; Pathology ; Tissue Donors