Silensor阻鼾器治疗前后阻塞性睡眠呼吸暂停综合征患者上气道结构改变的分析

目的 探讨Silensor阻鼾器治疗前后阻塞性睡眠呼吸暂停综合征(OSAS)患者上气道结构的改变。方法 采用X线头影测量法对42例OSAS患者Silensor阻鼾器治疗前后的上气道及其周围结构的形态进行测量,并对测量的42项结果进行配对t检验。结果 经阻鼾器治疗后,OSAS患者的软腭后气道增大最显著,软腭后-软腭后咽壁距由（9.10±2.25） mm 增加到（12.24±2.61） mm,舌根后气道间隙由（8.99±3.20） mm增至（11.24±3.79） mm,软腭与舌体接触长度由（26.26±6.04） mm 减小至（14.37±8.14） mm,舌骨-下颌平面距由（21.27±6.12） mm减小为（12.14±5.89） mm,会厌谷与颏后点间的距离由（55.15±5.61） mm减小为（51.63±5.87） mm。口咽气道面积和喉咽气道面积分别由（7.01±1.54） mm2和（3.02±0.89） mm2增大为（7.85±1.61） mm2和（3.61±1.61） mm2。结论 Silensor阻鼾器治疗后OSAS患者的上气道间隙明显增大。     

Influence of the photoinitiator system and light photoactivation units on the degree of conversion of dental composites

The aim of this study was to observe the influence of two light polymerization units (LED or halogen light) on the degree of conversion (DC) of three dental composites with lighter shades and a different photoinitiator system. The top (T) and bottom (B) surfaces of 60 discs of composite resin (Filtek? Supreme, Filtek? Z250, Tetric? Ceram Bleach) cured either by LED or by halogen lamp (HL) were studied using an FT-Raman spectrometer. The degree of conversion (DC) was evaluated by following the changes in the intensity of the methacrylate C=C stretching mode at 1640 cm?1. The calculated DC ranged from 54.2% (B) to 73.4% (T) and from 60.2% (B) to 76.6% (T) for the LED and HL, respectively. LED and halogen devices were able to produce an adequate DC for all the resins tested.     

Evaluation of Shear Bond Strength of Zirconia Bonded to Dentin After Various Surface Treatments of Zirconia

Establishing a reliable bond of resin cement to zirconia based materials has been a major limitation against zirconia restoration. Purpose of study: This study evaluated the shear bond strength of zirconia bonded to dentin specimens using a self etch dual cure resin cement after various surface treatments of zirconia. Twenty zirconia rods (3 × 2.5 mm) were prepared from zirconia blocks and assigned into 5 groups for the following surface treatments. (1) Group I: Control (C) no treatment (2) Group II: airborne-particle abrasion (APA), (3) Group III: hydrofluoric acid etching (HF), (4) Group IV: hydrofluoric acid etching followed by silanation (HF/S), and (5) Group V: application of zirconia primer (Z). Dentin Specimens were prepared from extracted molars stored in 0.5% chloramine-T. Zirconia rods were bonded to dentin using resin cement (Multilink Speed), then light polymerized. The specimens tested for failure were tested using the notched shear bond test method in a universal loading apparatus. One way ANOVA followed by Tukey HSD for cell means were used to analyze the data (=0.05). The highest values were obtained with group V (Z) (8.66 MPa) followed by group II (APA) (6.71 MPa), and group IV (HF/S) (4.41 MPa). The least values were obtained for group III (HF) (3.88 MPa) with no significant difference (P value 0.53) between group III (HF) (3.88 MPa) and group I (C) (3.70 MPa). Among the surface treatments employed in this study zirconia primer application is a practical procedure to improved bond strength of zirconia to resin cement followed by Airborne Particle Abrasion with 50 μm Al₂O₃ particles.     

Quality of written communication and master impressions for fabrication of removable partial prostheses in the Kingdom of Bahrain

The aim of this study was to examine the quality of written instructions and choice of impression trays and materials for removable partial dentures (RPDs) in the Kingdom of Bahrain. All six private dental laboratories in Bahrain were contacted and invited to participate in the study. Five laboratories participated, and submitted written instructions received by them for fabrication of both acrylic (A-RPDs) and cobalt-chromium (CC-RPDs) RPDs. These were examined for evidence of selected design variables. Types of impression trays and materials used were also recorded. One hundred and thirty-one written instructions were examined. Eleven percent (n = 14) were for CC-RPDs, 89% (n = 117) for A-RPDs. All treatments were provided on a private basis. Fifty-seven percent (n =1 8) of CC-RPD instructions requested the technician to design the prosthesis, 43% (n = 6) contained a diagram and 43% (n = 6) mentioned all design variables. Seventy-nine percent (n = 92) of A-RPDs requested the technician to design the denture, and only 1% (n = 1) mentioned all design variables. Alginate impression material was most commonly used for master impressions (83% of impressions (n = 109); 85% (n = 99) of A-RPDs, and 71% (n = 10) of CC-RPDs). Master casts were poured after a minimum of 24 h. Acrylic custom trays were used in 14% (n = 19) of cases (43% (n = 6) of CC-RPDs; 13% (n = 15) of A-RPDs). The quality of written instructions to dental laboratories for the fabrication of RPDs was found to be inadequate in Kingdom of Bahrain. There was widespread use of inappropriate impression trays and materials.     

Immunocytochemical detection of herpes viruses in oral smears of HIV-infected patients

Cytologic smears (CS) were taken from the lateral border of the tongue of HIV-seropositive patients (HIV+) (n = 39) and of seronegative controls (HIV-) (n = 19) and examined by immunocytochemistry (APAAP) and in situ hybridization (ISH) (biotinylated DNA probes) for the presence of viral antigens/DNA of EBV and CMV. While none of the HIV controls showed positive results for EBV antigen, 61% (APAAP) resp. 79% (ISH) of oral epithelial cells in the group of HIV+ patients were EBV-positive. While all CS taken from areas with the clinical diagnosis of hairy leukoplakia (HL) were EBV positive (APAAP and/or ISH), the detection of EBV in CS from uninvolved oral mucosa seemed to be associated with the later development of HL. In the group of HIV+ patients the detection rate for CMV was about five times (APAAP) resp. three times (ISH) higher than in HIV- persons. This non-invasive technique seems to be a valuable tool to screen for viral antigens/genomes.     

Utilization of a hospital for treatment of pediatric dental emergencies

PURPOSE: The purpose of this study was to investigate dental emergencies treated at a hospital clinic and emergency department (ED) to: (1) analyze emergency types; (2) determine reasons for seeking hospital care; and (3) examine trends compared to previous studies from this institution. METHODS: Records of 2,683 emergencies from 1995 to 2003 were reviewed. Demographics, reason for seeking care, and treatment details were analyzed overall by emergency type and for subgroups of patients with severe early childhood caries (S-ECC) and patients referred from other EDs. RESULTS: Emergencies were: 51% trauma, 40% caries, and 9% "other" emergencies unrelated to trauma or caries. Common patient characteristics were: (1) young age; (2) non-Caucasian ethnicity; (3) Medicaid as payer; (4) no dentist; and (5) proximity to the hospital. Caries emergencies increased significantly over the study period (P = .008), and 22% had S-ECC. Patients referred from other EDs were: 11% of trauma patients who commonly required sutures and/or extractions; and 3% of caries patients, 82% with extraoral swelling. CONCLUSIONS: Characteristics of patients seeking hospital care for dental emergencies were: (1) young age; (2) non-Caucasian ethnicity; (3) Medicaid as payer; (4) no dentist; and (5) proximity to CHRMC. Use differed by ethnic groups: Caucasians presented mostly for trauma; African Americans presented equally for caries and trauma; and Hispanics and Asians presented primarily for caries. Access to care, caries, and severe early childhood caries remain significant problems despite multiple programs targeting children's' oral health in Washington State.     

Systematic assessment of color removal following vital bleaching of intrinsically stained teeth

Various treatment variables associated with a standard bleaching technique were systematically recorded in 53 individuals exhibiting intrinsic discoloration of permanent teeth. These variables (predictors) included: (1) etiology (fluoride or tetracycline); (2) age of the patient; (3) the presented color of the stain; (4) the intensity of that color; (5) a long versus short bleaching time technique; and (6) the number of bleaching sessions. These were assessed as to their relationship with the results of treatment (dependent variable). The findings of a multiple regression analysis revealed that the contributions of the individual predictors were significantly different between those stains caused by tetracycline ingestion (N = 27) and those stains due to fluoride ingestion (N = 20). The analysis also revealed that those variables contributing to a significant proportion of the variance in results of treatment when tetracycline was the cause were: (1) the color of the stain and (2) the number of bleaching sessions. When fluoride was apparently the causal agent: (1) the bleaching time technique; (2) age of the patient; (3) color of the stain; and (4) the number of bleaching sessions contributed to a significant proportion of the variance in the results of treatment.     

Effect of surface treatment on roughness and bond strength of a heat-pressed ceramic

STATEMENT OF PROBLEM: Bonding ceramic restorations to tooth structure relies on treatment of the ceramic intaglio surface, selection of a suitable resin luting agent, and appropriate treatment of prepared tooth structure. Various ceramic surface treatments have been advocated which produce different topographies and bond strengths, but little information is available to identify the interaction between the resulting surface topography and bond strength. PURPOSE: The purpose of this in vitro study was to evaluate the effect of surface treatments on surface roughness and bond strength to dentin and enamel of a commercially available heat-pressed dental ceramic (IPS Empress). MATERIAL AND METHODS: One hundred heat-pressed ceramic disks were fabricated according to the manufacturer's recommendations. Specimens were divided into 5 groups (n=20) and treated with 1 of the following: (1) etching with 9.5% hydrofluoric acid, (2) 50%, or (3) 60% orthophosphoric acid and airborne-particle abrasion with (4) 50-microm, or (5) 250-microm alumina for 10 seconds. Morphological changes obtained with the surface treatments were investigated with a surface texture analyzer on half of the treated specimens. Two additional specimens from each group were treated and prepared for scanning electron microscopy. The specimens were then used for a bond strength test. The treated specimens were silanated and luted with a composite resin luting agent (Nexus 2) to enamel (n=50) and dentin (n=50) surfaces with 10 specimens for each treatment group. The luted specimens were loaded to failure in a universal testing machine in the shear mode with a crosshead speed of 0.05 mm/min. The data were analyzed with 1-way ANOVA followed by the Ryan-Einot-Gabriel-Welsch Multiple Range Test (alpha=.05). RESULTS: Surface treatments resulted in significant differences for surface topography and shear bond strength (P<.001). Mean surface roughness (Ra) (SD) was (2.54 (0.21) microm) for ceramic surfaces treated with 50-microm aluminum powder. Treatment of ceramic specimens with 50% orthophosphoric acid appeared to result in a smoother surface (1.02 (0.38) microm). The highest mean bond strength (SD) to enamel (14.7 (0.6) MPa) and dentin (8.2 (1.5) MPa) was associated with hydrofluoric acid etching. The lowest mean bond strength (SD) to enamel (2.7 (0.8) MPa) and dentin (1.5 (0.1) MPa) was recorded for 50% phosphoric acid. CONCLUSIONS: Hydrofluoric acid treatment resulted in the generation of pores and grooves that produced the greatest bond strength between the ceramic and tooth dentin and enamel. Orthophosphoric acid treatment was the least effective surface treatment method evaluated. The results are applicable to only the all-ceramic/luting system evaluated.     

Scanning electron microscopy of molar enamel structure of cricetodontine neogene rodents

Ultrastructural characters of enamel were studied as a phylogenetic indicator in a family of rodent fossils: the Cricetidae. The extinct group Cricetodon-Ruscinomys is a known lineage which span 17 million of years (from -20 My to -3 My). The three-dimensional organization of enamel of the left M1 was studied in 8 cricetid species at three different levels: (1) the chewing surface; (2) the middle of the crown; (3) the cervical part, close to the root. The arrangement and other details of enamel prisms varied according to five factors: (1) tooth morphology (there were differences between the four faces of the same molar); (2) enamel thickness; (3) level of crown; (4) degree of hypsodonty; (5) chronological age of the extinct species.     

Microtensile bond strength of a resin cement to glass infiltrated zirconia-reinforced ceramic: the effect of surface conditioning.

OBJECTIVES: This study evaluated the effect of three surface conditioning methods on the microtensile bond strength of resin cement to a glass-infiltrated zirconia-reinforced alumina-based core ceramic. METHODS: Thirty blocks (5 x 5 x 4 mm) of In-Ceram Zirconia ceramics (In-Ceram Zirconia-INC-ZR, VITA) were fabricated according to the manufacturer's instructions and duplicated in resin composite. The specimens were polished and assigned to one of the following three treatment conditions (n=10): (1) Airborne particle abrasion with 110 microm Al(2)O(3) particles + silanization, (2) Silica coating with 110 microm SiO(x) particles (Rocatec Pre and Plus, 3M ESPE) + silanization, (3) Silica coating with 30 microm SiO(x) particles (CoJet, 3M ESPE) + silanization. The ceramic-composite blocks were cemented with the resin cement (Panavia F) and stored at 37 degrees C in distilled water for 7 days prior to bond tests. The blocks were cut under coolant water to produce bar specimens with a bonding area of approximately 0.6mm(2). The bond strength tests were performed in a universal testing machine (cross-head speed: 1mm/min). The mean bond strengths of the specimens of each block were statistically analyzed using ANOVA and Tukey's test (alpha相似文献   

The effect of the addition of poly(methyl methacrylate) fibres on some properties of high strength heat-cured acrylic resin denture base material

The self-reinforcement of acrylic resin with butadiene styrene surface treated poly(methyl methacrylate) fibres has been reported to have the potential to substantially improve the transverse bend strength of conventional heat-cured acrylic resin. The aim of this study was to investigate the effect of the addition of butadiene styrene surface treated poly(methyl methacrylate) fibres in cross-ply arrangement to high impact acrylic resin on the transverse and impact strength. Specimens were prepared as specified in the International Standard Organization and British Standards for the Testing of Denture Base Resins (ISO 1567, 1988; BS 2487, 1989) and the British Standard Specification for Orthodontic resins (BS 6747, 1987) for transverse bend and impact testing. The impact strength was measured using a Zwick pendulum impact tester and the transverse bend strength measured using a Lloyds Instruments testing machine. The results showed that the impact strength was not improved with the addition of fibres, high impact acrylic resin with fibres (LF) 11.1 kJ m-2 and high impact acrylic resin (L) (12.5 kJ m-2). The modulus of rupture was decreased with the addition of fibres (57.8 MPa) for (LF) compared with (60.4 MPa) for (L). The modulus of elasticity was also reduced with the addition of fibres (1834.9 MPa) (LF) and 2086.2 MPa (L) as was the peak load (LF) (50.8 N) and (L) (55.8 N). It was concluded that the addition of surface treated poly(methyl methacrylate) fibres in cross-ply arrangement to high strength acrylic resin did not produce an improvement in the impact or transverse strength and cannot be recommended as a method of reinforcement.     

Influence of different treatment approaches on the removal of early plaque biofilms and the viability of SAOS2 osteoblasts grown on titanium implants

The aim of the present study was to evaluate the influence of different treatment approaches on: (1) the removal of early plaque biofilms grown on titanium implants, and (2) the biocompatibility of the instrumented implant surfaces. Five volunteers wore acrylic splints with sand-blasted and acid-etched titanium discs for 24 h to build up supragingival plaque. A total of 80 specimens were randomly assigned to the following groups: (1) an Er:YAG laser (100 mJ/pulse, 10 Hz) (Y), (2) an ultrasonic system (U), (3) plastic curettes and rinsing with chlorhexidine digluconate (P), or (4) unworn titanium discs (C). Autoclaved specimens were incubated with SAOS2 cells for three days. The following parameters were measured: treatment time (T), residual plaque biofilm (RPB) and clean implant surface (CIS) areas (%), and mitochondrial cell activity (MA) (counts/s). Statistical analysis within and between groups revealed the following mean scores (±SD): RPB areas: P (61.1±11.4) > U (36.8±4.5) > Y (5.8±5.1); CIS areas: Y (94.2±5.1) > U (63.2±4.5) > P (38.9±11.2); T: Y (5.6±1.2) > U (2.4±0.5) > P (2.3±0.5); MA: C (1.528.636±188.371) > U (831.594±370.228) > Y (678.250±367.902) > P (144.105±120.961). Within the limits of the present study, it may be concluded that Y seems to be most suitable for the removal of supragingival early plaque biofilms grown on SLA titanium implants, and (2) all treatment procedures failed to restore the biocompatibility of previously-contaminated SLA titanium surfaces.     

Effect of phosphorylation on the interaction of calcium with leucine-rich amelogenin peptide

Amelogenin undergoes self-assembly and plays an essential role in guiding enamel mineral formation. The leucine-rich amelogenin peptide (LRAP) is an alternative splice product of the amelogenin gene and is composed of the N terminus (containing the only phosphate group) and the C terminus of full-length amelogenin. This study was conducted to investigate further the role of phosphorylation in LRAP self-assembly in the presence and absence of calcium using small angle X-ray scattering (SAXS). Consistent with our previous dynamic light-scattering findings for phosphorylated (+P) and non-phosphorylated (-P) LRAP, SAXS analyses revealed radii of gyration (R(g)) for LRAP(-P) (46.3-48.0 ?) that were larger than those for LRAP(+P) (25.0-27.4 ?) at pH 7.4. However, added calcium (up to 2.5 mM) induced significant increases in the R(g) of LRAP(+P) (up to 46.4 ?), while it had relatively little effect on LRAP(-P) particle size. Furthermore, SAXS analyses suggested compact folded structures for LRAP(-P) in the presence and absence of calcium, whereas the conformation of LRAP(+P) changed from an unfolded structure to a more compact structure upon the addition of calcium. We conclude that the single phosphate group in LRAP(+P) induces functionally important conformational changes, suggesting that phosphorylation may also influence amelogenin conformation and protein-mineral interactions during the early stages of amelogenesis.     

Correlations of sinus, conical elevation, median depression of the lower lip and types of oral clefts

The incidence of autosomal dominantly inherited Van der Woude's syndrome among Finnish patients with cleft lip and palate CL(P) and with isolated cleft palate (CP) is approximately 2.5%. The incidence of conical elevation of the lower lip (CE) is 39% in CP and 0.8% in CL(P) patients. A pathogenetic similarity of sinuses and CE's was noted. The following classification was used to study associations between sinuses and CE's: (1) sinus; bilateral, unilateral, atypical; (2) CE: bilateral, unilateral; (3) median depression of the lower lip (MD); (4) combined sinus and CE; (5) combined CE and MD. According to the classification developed, a group of 77 sinus patients and 156 CE and/or MD patients was classified in subgroups of CL(P), CP, Pierre Robin anomalad (PR) and non-cleft subjects. The findings were: the sinus was bilateral on 52%, unilateral in 34% and atypical in 14%; the CE without associated sinus was bilateral in all cases; the sinus was associated with CE in 77% of all sinus subjects. The highly increased incidence of the CE in the CP (92%) and in the CL(P) (61%) sinus groups compared to the incidences of CE in these groups in general (39% and 0.8%) shows a close relationship between these 2 disorders of the lower lip, but the similarity of the genetic etiology still remains unclear.     

Effect of various calcium/phosphates ratios of carboxymethylcellulose-based saliva substitutes on mineral loss of bovine enamel in vitro

OBJECTIVES: The present study evaluated the effects of various calcium and phosphate concentrations and ratios of carboxymethylcellulose (CMC)-based solutions on the mineral loss of predemineralised bovine enamel in vitro. METHODS: Bovine enamel specimens were prepared, polished and partly covered with nail varnish, thus serving as control of sound enamel. After demineralisation (37 degrees C; pH 5.0; 14 days) the specimens were exposed to CMC-based solutions (20g/l) with various saturations with respect to apatites containing 0.1mM NaF, CaCl2 (0-32 mM) and KH2PO4 (0-52 mM) at two different pH values (5.5 or 6.5). A fluoride-free solution served as control, and four commercially available products were tested as well. The differences in mineral loss (DeltaDeltaZ) between the values prior to (DeltaZ Demin) and after storage (DeltaZ Effect) in the various solutions were evaluated from microradiographs of thin sections (100microm). RESULTS: The general linear model revealed a significant dependency for DeltaDeltaZ on 'calcium' (p<0.001), 'phosphate' (p=0.023), 'fluoride' (p=0.002) and 'pH' (p<0.001). With increasing calcium and phosphate concentrations an increase in DeltaDeltaZ could be observed up to the solution containing the third highest saturation with respect to octacalciumphosphate (3.2), showing a significant remineralisation (p<0.05; t-test). The commercially available products as well as the control groups revealed significantly reduced DeltaDeltaZ values compared to this group (p<0.01; Bonferroni). CONCLUSIONS: A saturation with respect to octacalciumphosphate of 3.2 and a pH of 6.5 enables CMC-based solutions to remineralise bovine enamel in vitro.     

Clinical efficacy of flossing versus use of antimicrobial rinses

BACKGROUND: Dental floss is only used by a small part of the population on a daily basis. Therefore, an easy, applicable alternative is needed. This alternative could be a mouthrinse with antimicrobial activity for daily use. The aim of the present study was to evaluate the efficacy of two mouthrinses in reducing interdental plaque and gingivitis compared to dental floss. METHODS: A total of 156 healthy volunteers were randomly assigned to the following groups: 1) toothbrushing and rinsing (0.06% chlorhexidine and 0.025% fluoride); 2) toothbrushing and rinsing (0.1% cetylpyridiniumchloride and 0.025% fluoride); 3) toothbrushing and flossing; and 4) toothbrushing only (N = 39 subjects in each group). At baseline, the modified proximal plaque index (MPPI) and papillary bleeding index (PBI) were recorded. Thereafter, subjects had to brush in the usual manner during 8 weeks. Additionally, test groups had to rinse once a day (groups 1 and 2: 30 seconds) or to floss (group 3). Eight weeks after baseline, indices were recorded again and improvements were calculated. Analysis of variance (ANOVA) and the Bonferroni test served for statistical analysis. RESULTS: After 8 weeks, reductions for all indices were found in all groups (P <0.05). With respect to the MPPI, mouthrinse groups performed better than the control and floss groups: 1) 0.73; 2) 0.82; 3) 0.40; and 4) 0.32 (P <0.05). The PBI showed no statistically significant difference between groups: 1) 0.46; 2); 0.50; 3); 0.42; and 4) 0.37. CONCLUSION: The results suggest that, in combination with toothbrushing, daily use of the tested mouthrinses may result in a higher interproximal plaque reduction than daily flossing.     

Influence of attachment wear on retention of mandibular overdenture

The aims of this study were: (i) to evaluate and compare retention of two-teeth (implant) supported mandibular overdenture with either stud or magnetic attachments during linear (axial) and rotational (paraxial) dislodgements; (ii) to compare retentive properties before and after wear simulation. The test group consisted of five magnetic and four stud overdenture attachments (n = 12 specimens for each attachment type). Retention in axial direction was evaluated on one-tooth (implant) model by measuring maximum retentive force (N) and range of retention (mm) during the linear dislodgement. Retention in the paraxial direction was evaluated on mandibular-overdenture model by measuring the maximum retentive force (N) during three types of rotational dislodgements - anterior, lateral and posterior. The minimum number of cycles required to simulate wear was determined by special wear test. Afterwards, the wear was simulated in the test group, and retention in axial and paraxial directions was measured again. Statistical analysis: one-way anova, Scheffe post hoc and paired-samples t-tests (P < 0.05). Initially, studs had higher retention (4-11 N) than magnets (4.5-6 N) in axial direction. After the wear simulation, it had decreased from 76% to 48% for some of the studs and had become similar to the retention of magnetic attachments. Magnets had lower retention range (0.2-0.3 mm) than studs (0.5-1.1 mm). Studs provided similar or higher retention in paraxial directions than magnetic attachments both before and after wear simulation. Retentive properties of magnets decreased mostly with posterior rotational dislodgement. Retentive properties of stud overdenture attachments were less constant.     

Patterns of integrin expression in a human mandibular explant model of osteoblast differentiation

Cell-matrix interaction is crucial in regulating osteoblast differentiation and function. These interactions are themselves regulated, at least in part, by integrins. Although there are some data from mammalian models, few studies have compared integrin expression at different stages of the osteoblast lineage. Here, primary human mandibular osteoblast cultures were grown in the presence of epidermal growth factor (EGF), giving a proliferative, less differentiated phenotype, or of vitamin D(3) and hydrocortisone (D+Hc), giving a more differentiated phenotype. These cultures were compared with those of cells prepared in the absence of EGF or D+Hc by fluorescence-activated cell sorter using a panel of monoclonal antibodies to specific integrin heterodimers. To provide in vivo correlation, the same panel of antibodies was used to stain fresh-frozen, undemineralised sections of human mandibular bone. Under baseline conditions the alpha(3), alpha(5), alpha(v), alpha(v)beta(3), beta(3) and beta(1) integrin subunits were expressed strongly by the cells, with low-level expression of the alpha(1), alpha(2) and alpha(4) subunits. In the presence of EGF there was increased alpha(2) expression. With D+Hc, alpha(3) and alpha(5) expression was elevated. Immunohistochemical analysis demonstrated alpha(2), alpha(3), alpha(5), alpha(v)beta(3), beta(1) and beta(3) subunits in cells of the osteoblast lineage; alpha(2) staining was restricted to cells close to the bone surface whilst alpha(v)beta(3) and beta(3) were most frequently localised in the osteocytes. The results provide evidence that cells at successive stages of the osteoblast lineage show different patterns of integrin expression. These integrins may be important in cell-matrix interactions leading to osteoblast differentiation.     

变形链球菌I型Mutans表面蛋白P1的粘附作用

In this study,the surface protein P(1) of Streptococcus mutans MT(6)R(Serotype C) was extracted from the culture supernants,purified by PAGE,identified by the standard antisera and labelled by with (131)I.The adherence of (131)I protein P(1)((131)I-P(1)) to the saliva-coated hydroxyaptite (S-HA) of the CF (caries-free,22,DFS=0) were studied.The adhesion of (131)I-P(1) to the S-HA promoted a greater extent than that to the HA treated with buffer and bovine serum albumin(P<0.01).This result suggested that protein P(1) may be one of the important adhesins of S.mutans.     

Pharmacokinetic significance of measurement of salivary penetration of protein-unbound pyridonecarboxylic acid antimicrobial agents

The author attempted to determine the feasibility of monitoring blood concentration of antimicrobial agents by estimating blood levels of the agents on the basis of their content in saliva. Since it is difficult to determine drug tissue-penetration degree in humans, at present, tissue concentrations must be estimated from corresponding blood concentration. In the case of orally administered drugs exhibiting great individual differences in absorption by the gastrointestinal tract, frequent blood collection is required for blood-concentration monitoring. Noninvasive and very simple saliva collection, on the other hand, has already been used for monitoring concentrations of such drugs as carbamazepine and antiepileptics. PPA, ENX, NFLX, and OFLX are pyridonecarboxylic acid antimicrobial agents of great usefulness because of their expanded antimicrobial spectrum and their effectiveness even against gram-negative bacteria that exhibit no adequate response to other oral antimicrobial agents. After PPA, ENX, NFLX, and OFLX were administered orally to healthy volunteers, serum and saliva samples were collected. The samples were then centrifuged, deproteinized, and freeze-dried. 1. After the freeze-dried samples were dissolved to give tenfold to twentyfold concentrated solutions, levels of agents were bioassayed by means of the thin-layer-disc method. On the basis of the data obtained in this way, pharmacokinetic analyses were performed according to the one compartment model of Imoto and Yamaoka. A personal computer (NEC-8801, 9801) was used in drawing simulated curves. 2. Percentages of salivary as compared to serum concentrations were as follows: PPA (500 mg)-70, ENX (300 mg)-75, ENX (200 mg)-78, NFLX (200 mg)-35, and OFLX (200 mg)-105. Corresponding values for pharmacokinetic data were as follows: PPA (500 mg)-77.2, ENX (300 mg)-74.2, ENX (200 mg)-85.0, NFLX (200 mg)-30.0, and OFLX (200 mg)-91.6. Coefficients of correlation (r =) between salivary and serum concentrations in measured data were as follows: PPA (500 mg)-0.915, ENX (300 mg)-0.989, ENX (200 mg)-0.953, NFLX (200 mg)-0.887, and OFLX (200 mg)-0.886.(ABSTRACT TRUNCATED AT 400 WORDS)