The Pharmacokinetic Exposure to Fexofenadine is Volume-Dependently Reduced in Healthy Subjects Following Oral Administration With Apple Juice

Pharmacokinetic exposures to fexofenadine (FEX) are reduced by apple juice (AJ); however, the relationship between the AJ volume and the degree of AJ‐FEX interaction has not been understood. In this crossover study, 10 healthy subjects received single doses of FEX 60 mg with different volumes (150, 300, and 600 mL) of AJ or water (control). To identify an AJ volume lacking clinically meaningful interaction, we tested a hypothesis that the 90% confidence interval (CI) for geometric mean ratio (GMR) of FEX AUC_AJ/AUC_water is contained within a biocomparability bound of 0.5–2.0, with at least one tested volume of AJ. GMR (90% CI) of AUC_{AJ 150mL}/AUC_water, AUC_{AJ 300mL}/AUC_water, and AUC_{AJ 600mL}/AUC_water were 0.903 (0.752–1.085), 0.593 (0.494–0.712), and 0.385 (0.321–0.462), respectively. While a moderate to large AJ‐FEX interaction is caused by a larger volumes of AJ (e.g., 300 to 600 mL), the effect of a small volume (e.g., 150 mL) appears to be not meaningful.

3-T MRI safety assessments of magnetic dental attachments and castable magnetic alloys

OBJECTIVES

To assess the safety of different magnetic dental attachments during 3-T MRI according to the American Society for Testing and Materials F2182-09 and F2052-06e1 standard testing methods and to develop a method to determine MRI compatibility by measuring magnetically induced torque.

METHODS

The temperature elevations, magnetically induced forces and torques of a ferromagnetic stainless steel keeper, a coping comprising a keeper and a cast magnetic alloy coping were measured on MRI systems.

RESULTS

The coping comprising a keeper demonstrated the maximum temperature increase (1.42 °C) for the whole-body-averaged specific absorption rate and was calculated as 2.1 W kg⁻¹ with the saline phantom. All deflection angles exceeded 45°. The cast magnetic alloy coping had the greatest deflection force (0.33 N) during 3-T MRI and torque (1.015 mN m) during 0.3-T MRI.

CONCLUSIONS

The tested devices showed minimal radiofrequency (RF)-induced heating in a 3-T MR environment, but the cast magnetic alloy coping showed a magnetically induced deflection force and torque approximately eight times that of the keepers. For safety, magnetic dental attachments should be inspected before and after MRI and large prostheses containing cast magnetic alloy should be removed. Although magnetic dental attachments may pose no great risk of RF-induced heating or magnetically induced torque during 3-T MRI, their magnetically induced deflection forces tended to exceed acceptable limits. Therefore, the inspection of such devices before and after MRI is important for patient safety.

Positions of pluripotency genes and hepatocyte-specific genes in the nucleus before and after mouse ES cell differentiation

Spatial positioning of genes in the cell nucleus plays an important role in the regulation of genomic functions. Evidence for changes in gene positioning associated with transcriptional activity has been reported. However, our understanding of this phenomenon is still quite limited. We examined how pluripotency genes and hepatocyte-specific genes behave during the differentiation of mouse embryonic stem (ES) cells into hepatocytes, by targeting the loci of the Klf4, Nanog, Oct4, Sox2, Cyp7α1, Pck1, Tat, and Tdo2 genes, and using three-dimensional fluorescence in situ hybridization analyses. We found that each gene has a distinctly inherent localization profile in the ES cell nucleus. During differentiation, the Klf4, Nanog, Oct4, Cyp7α1, Pck1, and Tat loci shifted toward the nuclear center, while the Sox2 and Tdo2 loci shifted toward the periphery. The Klf4, Nanog, Oct4, and Tdo2 seem to prefer the outer regions, rather than the inner regions, when they are active. We also found that the radial positioning of the focused genes in the hepatocyte cell nucleus was highly correlated with the local GC content and the gene density of the surrounding region, but not with gene activity.

Azelnidipine is a calcium blocker that attenuates liver fibrosis and may increase antioxidant defence

BACKGROUND AND PURPOSE

Oxidative stress plays a critical role in liver fibrogenesis. Reactive oxygen species (ROS) stimulate hepatic stellate cells (HSCs), and ROS-mediated increases in calcium influx further increase ROS production. Azelnidipine is a calcium blocker that has been shown to have antioxidant effects in endothelial cells and cardiomyocytes. Therefore, we evaluated the anti-fibrotic and antioxidative effects of azelnidipine on liver fibrosis.

EXPERIMENTAL APPROACH

We used TGF-β1-activated LX-2 cells (a human HSC line) and mouse models of fibrosis induced by treatment with either carbon tetrachloride (CCl(4) ) or thioacetamide (TAA).

KEY RESULTS

Azelnidipine inhibited TGF-β1 and angiotensin II (Ang II)-activated α1(I) collagen mRNA expression in HSCs. Furthermore, TGF-β1- and Ang II-induced oxidative stress and TGF-β1-induced p38 and JNK phosphorylation were reduced in HSCs treated with azelnidipine. Azelnidipine significantly decreased inflammatory cell infiltration, pro-fibrotic gene expressions, HSC activation, lipid peroxidation, oxidative DNA damage and fibrosis in the livers of CCl(4) - or TAA-treated mice. Finally, azelnidipine prevented a decrease in the expression of some antioxidant enzymes and accelerated regression of liver fibrosis in CCl(4) -treated mice.

CONCLUSIONS AND IMPLICATIONS

Azelnidipine inhibited TGF-β1- and Ang II-induced HSC activation in vitro and attenuated CCl(4) - and TAA-induced liver fibrosis, and it accelerated regression of CCl(4) -induced liver fibrosis in mice. The anti-fibrotic mechanism of azelnidipine against CCl(4) -induced liver fibrosis in mice may have been due an increased level of antioxidant defence. As azelnidipine is widely used in clinical practice without serious adverse effects, it may provide an effective new strategy for anti-fibrotic therapy.

Assimilation and translocation of nitrogen and carbon in Curcuma alismatifolia Gagnep

Curcuma or Siam tulip (Curcuma alismatifolia Gagnep.) is an ornamental flowering plant with two underground storage organs, rhizomes and storage roots. Characteristics of N and C assimilation and transport in curcuma were investigated. The plants were treated with (15)NH(4) (+) + (15)NO(3) (-) and (13)CO(2) at 10, 13 or 21 weeks after planting. Plants were sampled at several stages up to 32 weeks. The C stored in old storage roots was used rapidly during the first 10 weeks; after which N stored in old rhizomes and old storage roots were used. The daily gain in C depending on photosynthesis was remarkably high between 10 and 21 weeks. However, the daily gain in N was relatively constant throughout the growth period. The (15)N absorbed at 10 weeks was initially accumulated in leaves and roots, but some was transported to flowering organs at 13 weeks. At harvest, 41% of (15)N was recovered in new rhizomes and 17% in new storage roots. After (13)CO(2) exposure at 10 and 13 weeks, the distribution of (13)C among organs was relatively constant in subsequent stages. When given (13)CO(2) at 21 weeks, a large amount of labelled C was recovered in new storage roots and new rhizomes at harvest. Both new rhizomes and new storage roots stored N and C, however, rhizomes played a more important role in supplying N, while storage roots provided C.

An outbreak of psittacosis in a bird park in Japan

An outbreak of psittacosis related to a bird park occurred in Matsue City, Shimane Prefecture, Japan, during winter 2001. Seventeen cases of psittacosis (12 visitors, three staff, and two student interns) were confirmed. A cohort study was conducted among the park staff and students to determine the risk factors for the development of acute serologically confirmed psittacosis (SCP) infection. Being 'bird staff' had an increased risk of SCP infection (RR 3.96, 95% CI 1.48-10.58). Entering the staff building, where ill birds were maintained without proper isolation, was also associated with an increased risk of SCP infection (RR 3.61, 95% CI 1.03-12.6). Isolation of ill birds and quarantine measures were found to be insufficient. Dehumidifiers and a high-pressure water spray under a closed ventilation environment may have raised the concentration of Chlamydophila psittaci in the hothouses. Bird park staff and visitors should be educated about psittacosis.

Objective and subjective hardness of a test item used for evaluating food mixing ability

The aim of this study was to compare objective and subjective hardness of selected common foods with a wax cube used as a test item in a mixing ability test. Objective hardness was determined for 11 foods (cream cheese, boiled fish paste, boiled beef, apple, raw carrot, peanut, soft/hard rice cracker, jelly, plain chocolate and chewing gum) and the wax cube. Peak force (N) to compress each item was obtained from force-time curves generated with the Tensipresser. Perceived hardness ratings of each item were made by 30 dentate subjects (mean age 26.9 years) using a visual analogue scale (100 mm). These subjective assessments were given twice with a 1 week interval. High intraclass correlation coefficients (ICCs) for test-retest reliability were seen for all foods (ICC > 0.68; P < 0.001). One-way anova found a significant effect of food type on both the objective hardness score and the subjective hardness rating (P < 0.001). The wax cube showed significant lower objective hardness score (32.6 N) and subjective hardness rating (47.7) than peanut (45.3 N, 63.5) and raw carrot (82.5 N, 78.4) [P < 0.05; Ryan-Einot-Gabriel-Welsch (REGW)-F]. A significant semilogarithmic relationship was found between the logarithm of objective hardness scores and subjective hardness ratings across twelve test items (r = 0.90; P < 0.001). These results suggest the wax cube has a softer texture compared with test foods traditionally used for masticatory performance test, such as peanut and raw carrot. The hardness of the wax cube could be modified to simulate a range of test foods by changing mixture ratio of soft and hard paraffin wax.

Detection system of Cryptosporidium parvum oocysts by brackish water benthic shellfish (Corbicula japonica) as a biological indicator in river water

The brackish water benthic shellfish, Corbicula japonica, was experimentally exposed to Cryptosporidium parvum oocysts at 1.51x10(4)oocysts/clam/day for 7 or 14 days. Oocysts were predominantly eliminated through the feces of Corbicula japonica in both cases by microscopic and PCR methods. The fecal excretion rates of oocysts within 4 days after the last exposure to Corbicula japonica were 87.6% for the 7-day exposure group and 86.0% for the 14-day exposure group. The tissue residue level of oocysts in the gastrointestinal tract 3 days after the last exposure was 2.7% of total exposed oocysts and that of 7 days was 1.1% for the 7-day exposure case and 1.6 and 0.5% for the 14-day exposure case, respectively, maintaining infectivity to cultured cells (HCT-8) in vitro. At the same time, field tests of Corbicula japonica for collecting oocysts showed that this clam could certainly collect Cryptosporidium parvum oocysts in the natural river and, furthermore, the gene type of C. parvum could be also identified proving its effectiveness as a biological indicator. The present study showed that the brackish water benthic shellfish Corbicula japonica may be capable of gathering and preserving Cryptosporidium parvum oocysts to a considerable extent under the natural ecological conditions, and further suggests the effectiveness of Corbicula japonica as a practical and general bioindicator for estimates of river water contamination by oocysts of Cryptosporidium parvum.

Influence of food platform width of mandibular removable partial denture on food mixing ability

The aim of this study was to clarify the influence of food platform width on food mixing ability in patients with mandibular removable partial dentures (RPDs). Twelve subjects (six males and six females, mean age 56.8 years) with intact dentition except for unilaterally missing mandibular first and second molars participated in the study. The food platforms of their RPDs were made of light polymerized composite and three platform conditions were evaluated. A food platform (Control condition) had 7 mm width with a central focus on the top of the residual ridge. Narrowed platforms (5 mm) were created by trimming a lingual portion (Buccally oriented occlusion, Buccal condition) or a buccal portion (Lingually oriented occlusion, Lingual condition) from the control. Subjects chewed a standardized wax cube which provided an estimate of food mixing ability [Mixing Ability Index (MAI)] for each of the three platforms. A significant effect (P < 0.001) on the MAI was found for food platform type (repeated measures one-way analysis of variance). Tukey multiple comparisons found significant differences of MAI between Control condition (1.05 +/- 0.26) and Buccal condition (0.86 +/- 0.23) (P = 0.032), and between Control and Lingual condition (0.54 +/- 0.37) (P < 0.001). Furthermore, MAI with Lingual condition was significantly smaller than that with Buccal condition (P < 0.001). These results suggest that reduction in the width of the food platform may impair masticatory function and the buccal portion of mandibular food platform of RPD is more critical for food mixing than the lingual portion of the platform.

The influence of altered occlusal guidance on condylar displacement during submaximal clenching

As cited in literatures, canine protected occlusion has a potential to reduce clenching induced temporomandibular joint loadings. However, these previous studies did not perform a control of the clenching level which differed with the depending occlusal conditions. This result may be due largely to an associated reduced jaw closing muscle activity. The present study has investigated clenching induced condylar displacements with controlled clenching level. Twenty healthy human subjects (15 males and five females with an average age of 26.5 years) volunteered to participate in this study. Metallic occlusal overlays were fabricated for the lower working side canine and overlaid to the second molar and the non-working side second molar in order to simulate a canine protected occlusion, group function occlusion and bilateral balanced occlusion. Electromyographic (EMG) activity from the bilateral masseter, anterior temporalis, and posterior temporalis was recorded. These signals were rectified, summarized, and presented to each subject using an oscilloscope screen. Using this visual feedback, subjects were asked to perform clenching tasks at a 50% level of maximal voluntary contraction exerted with simulated group function occlusion and three-dimensional condylar displacements were recorded. An experimental occlusal pattern that shows statistically significant affects on condylar displacements (anova: P<0.001) was found. When compared with the simulated canine protected occlusion, the simulated group function occlusion caused smaller working side condylar displacement and the simulated bilateral balanced occlusion caused significantly smaller non-working side and working side condylar displacements. These results suggest that the increased working side tooth contacts have a potential to reduce working side joint loadings, and a balancing side contact has a potential to reduce non-working side joint loadings, under the laboratory condition where the clenching level is controlled.

Detection of improvement in the masticatory function from old to new removable partial dentures using mixing ability test

The aim of this study was to determine the sensitivity of the Mixing Ability Test to detect improvement of masticatory function in subjects on transition from old to new removable partial dentures. Thirty-two subjects (seven males, 25 females, mean age 65.0 years) with distal extension partially edentulous area in mandible and/or maxilla participated in the study. The following reasons were presented for replacing the old removable partial dentures with new ones: fracture and/or poor fitness of retainers, extraction of abutment teeth, poor fitness of denture base, severe wear of artificial teeth and request for metal base dentures. Masticatory function with old and new removable partial dentures after an adaptation period (mean 27.4 weeks) was evaluated by the Mixing Ability Test. Subjects were asked to masticate five two-coloured wax cubes with each removable partial denture. Mixing Ability Index was obtained from the colour mixture and shape of the masticated cubes. Wilcoxon signed-rank test was used to test the difference of Mixing Ability Indexes between old and new removable partial dentures. The mixing ability indexes with new removable partial dentures (mean+/- s.d.: 0.70+/- 0.68) was significantly higher (P<0.001) than those with old removable partial dentures (-0.11+/-1.13). The results suggest that the Mixing Ability Test was capable of detecting improvement in masticatory function with new removable partial dentures.

Finite element contact stress analysis of the RPD abutment tooth and periodontal ligament

OBJECTIVES

The purpose of this study was to determine the influence of the occlusal rest position in removable partial dentures on the displacement of the abutment tooth and the stress distribution in the periodontal ligament (PL).

METHODS

We constructed three-dimensional finite element models of the mandibular first and second premolars. A layer of the PL and a mesial or distal occlusal rest were produced on the second premolar as an abutment. A zero displacement was prescribed on the outer surface of the PL and the first premolar. In each simulation, the rest was moved 0.05 mm vertically to the apical direction, with or without restriction of horizontal movements. We simulated the contact phenomena on the abutment surfaces, and calculated the movements of the abutment and stress distributions in the PL.

RESULTS

We observed a maximum distal displacement of 42 microm at the buccal cusp of the abutment and a principal compressive stress of 0.35 MPa in the PL when the abutment was vertically loaded by a distal rest that was allowed to move horizontally. However, the displacements and stresses were relatively small, and were all within the physiological limitations of the tissues. The restriction of the horizontal movement of the rests was effective in reducing the horizontal displacements of the abutment, regardless of the rest position.

CONCLUSIONS

The single vertical load exerted from either the mesial or distal rest on the abutment was unlikely to cause any mechanical damage to its supporting tissues.

Salmonella Enteritidis outbreak associated with a school-lunch dessert: cross-contamination and a long incubation period, Japan, 2001

A Salmonella Enteritidis (SE) outbreak in Japan was investigated with an observational study, analytical epidemiology and bacteriological examination (including phage typing). The outbreak occurred among 96 schoolchildren, and was caused by SE phage type 1. The outbreak source was dessert buns served at a school lunch (RR 42.55, 95 % CI 5.93-305.11, P < 0.001). The buns were probably cross-contaminated from eggs from a factory with a history of SE-contaminated products. The incubation period was longer than usual (3-16 days, median 8 days). A low contaminating dose may account for the long incubation period and low attack rate. Outbreak detection was hampered by the absence of routine Salmonella surveillance in Japan. The investigation was complicated by concurrent illnesses from other SE phage types. It was successful, in part, because adequate food samples were available for microbiological testing.

Effect of metal strengthener length on stress distribution in acrylic denture bases: a finite element study

This study investigated the influence of metal strengthener length on stress created in acrylic denture bases in relation to location of the vertical support to the dentures. Finite element analysis was conducted to calculate stress generated in the straps of 2 mm-thickness and 18 mm-width that were reinforced with metal strengtheners of five different lengths. A vertical biting force of 60 N was directed on one end of each strap, while the other end was fixed. Vertical movements were restricted at one of the three support locations between the centre of the strap and the loading site. When the straps were vertically supported near the loading site, greater maximum tensile stresses were seen in the straps with relatively short strengtheners than those shown in the straps with longer strengtheners. The metal strengtheners with sufficient length may provide a preventive denture design against the acrylic fractures.

ProNectin F-grafted-ethylene vinyl alcohol copolymer (EVAL) as a liquid type material for treating cerebral aneurysm—An in vivo and in vitro study

The authors aimed to develop a liquid material for embolization of aneurysms. In vitro and in vivo performances of the new embolic material were examined by cell culture and using an aneurysm model made in common carotid arteries (CCAs) of adult rats. Engineered protein ProNectin F (PnF), which contains 13 sites of an arginine-glycine-aspartic acid (RGD), was grafted onto ethylene vinyl alcohol copolymer (EVAL-g-PnF). The liquid material, EVAL-g-PnF dissolved in DMSO, was infused into an aneurysm model. The blood segments were harvested 2, 5, and 14 days and examined histologically. A number of bovine coronary artery endothelial cells became able to attach to and form cobblestone-like islands on the EVAL by incorporating PnF. The aneurysm model infused with the EVAL-g-PnF solution revealed that the aneurysm lumen was filled with proliferated fibroblasts and macrophages. On the other hand, the aneurysm model treated with unmodified EVAL showed that the cavity was almost filled with EVAL mass and that fibroblasts and macrophages filled a narrow space between the EVAL mass and the cavity wall. The results indicate that EVAL-g-PnF could be more suitable for reorganizing the cavity of an aneurysm than native EVAL.

3-D Finite element analysis of all-ceramic posterior crowns

The purpose of this study was to evaluate the stress distribution under various loading conditions within posterior all-ceramic crowns. A three-dimensional finite element model representing a lower first molar was constructed. Variations of the model had two types of single layer all-ceramic crowns (Dicor and Empress) and two types of double layer all-ceramic crowns (In-Ceram and Empress2) cemented. A load of 600 N, simulating the maximum bite force, was applied vertically to the crowns. Loads of 225 N, simulating masticatory force, were applied from three directions (vertically, at a 45 degrees angle, and horizontally). In the test simulating maximum bite force, the maximum tensile stresses on all crowns (17.4-19.4 MPa) concentrated around the loading points. In the masticatory force simulation test, the specimens experienced maximum tensile stresses of 19.7-27.0 MPa under a horizontal load and 10.8-10.9 MPa under a vertical load. When the load was applied horizontally, the maximum tensile stress was observed around the loading points on the surface in the case of the single layer crowns, and of the cervical area of the inner core of the double layer crowns. Within the limitation of this study, it was found that the strength of occlusal contact points is important to the integrity of posterior all-ceramic crowns and that bite forces applied from the horizontal direction are a critical factor.

Influence of working side contacts on masticatory function for mandibular distal extension removable partial dentures

The aim of this study was to clarify the influence of working side contacts for masticatory function for a distal extension removable partial denture. Five subjects who had edentulous arches from second premolar to second molar opposing natural teeth participated. Working side contacts were altered by using three types of artificial teeth attached to the denture base. A-form teeth made contact with opposite teeth while acting as the working side in a lateral excursion. The cusp angles of B- and C-form teeth were decreased by 10 degrees and 20 degrees, respectively compared with A-form teeth. B-and C-form teeth discluded with opposite teeth on the working side. Subjects were asked to perform two kinds of masticatory performance test. Obtained data were evaluated by the repeated-measures anova and the Tukey test for multiple comparisons. Results revealed that there was a significant difference (P=0.001) in the three types of teeth in the mixing ability test and the value of A-form teeth was statistically less value than those of the other teeth. However, there was no significant difference in the comminuting ability test. These results suggested that working side contacts between artificial teeth and opposite natural teeth influenced mixing ability, but not comminuting ability.

Validity and reliability of a newly developed method for evaluating masticatory function using discriminant analysis

The objective of the study was to assess validity and reliability of a newly developed method for evaluating mixing ability of masticatory function. A two-coloured paraffin wax cube was used as a test food in the mixing ability test. Eleven full dentate and 33 denture wearers participated in the validity assessment. They were divided into three groups according to their dental state. Validity was assessed by the Spearman's coefficient of correlations between the mixing ability test and the sieving method used as a 'gold standard' test of the masticatory performance. The subjects were asked to masticate the test foods for 5, 7, 10, 15, 20 and 30 strokes in each test. Significant correlations (P < 0.001) were obtained in natural dentition group (r(s) = 0.66), in denture-natural dentition group (r(s) = 0.72) and in denture-denture group (r(s) = 0.56). In the reliability assessment, three full dentate subjects were asked to repeat the mixing ability test a number of times. The intraclass correlation coefficients were 0.94 in interexaminer consistency, 0.98 in intra-examiner consistency, 0.89 in test-retest consistency and 0.99 in measuring consistency. These results indicated that the mixing ability test had the validity and the reliability for evaluation of the masticatory performance.

Bone mineral density of the mandible in ovariectomized rats: analyses using dual energy X-ray absorptiometry and peripheral quantitative computed tomography

INTRODUCTION

Although previous studies have shown that maxillary molar extraction in ovariectomized (OVX) animals causes mandibular loss of bone, it is still questionable as to whether estrogen deficiency affects mandibles with functional occlusion.

MATERIALS AND METHODS

To answer this question, 13-week-old female Sprague-Dawley rats were bilaterally OVX or sham-operated. After 109 days, the bone mineral density (BMD) of the femurs and mandibles was measured using dual-energy X-ray absorptiometry (DEXA) and peripheral quantitative computed tomography (pQCT).

RESULTS

In DEXA analysis, although the BMD of the total mandible of the OVX rats was similar to that of the sham-operated rats, the BMD of the condylar region in the OVX rats had decreased by 12.5%. In pQCT analysis, decrease in trabecular BMD of the mandibular bone was detectable but low in the molar region (maximal 13%), whereas no difference was seen in cortical BMD. In the femurs, the trabecular bone prominently decreased in OVX rats (30% decrease in pQCT analysis) as previously reported.

CONCLUSION

This study revealed regional differences in the mandibular bone decrease in OVX rats. Although the mechanism of low susceptibility of the mandible to estrogen-deficient conditions remains unknown, it is likely that mechanical stress derived from functional occlusion is preventing bone loss in this pathological condition. Furthermore, this study demonstrated the advantage of pQCT in analyzing rat mandibular bone.

A new and simple method for evaluating masticatory function using newly developed artificial test food

The aim of this study was to develop an objective evaluation system for the masticatory function. This system used paraffin wax cubes as a test food, which had six red- and green-coloured layers so that each of the six surfaces showed a pseudo-checkered pattern. A total of 100 paraffin cubes were chewed by 37 subjects and the images of these samples were captured and analysed using a digital image analyzer. With regard to the colour and the shape of each sample, five parameters were obtained. Furthermore, an independent examiner graded the degree of colour mixing in the chewed samples into three groups (poor, medium and good) by visual inspection. A discriminant analysis was performed using the five variables as predictors of two groups (good and poor). Mixing Ability Index (MAI) was calculated from the discriminant function and using this index, 97% of the samples from these two groups were classified correctly. This system needed only a few minutes to complete and is easy to use. Therefore, it has high potentials for clinical use.

Testing a symptom-based surveillance system at high-profile gatherings as a preparatory measure for bioterrorism

We tested symptom-based surveillance during the G8 conference in 2000 as a means of detecting outbreaks, including bio-terrorism attacks, promptly. Five categories of symptoms (skin and haemorrhagic, respiratory, gastrointestinal, neurological and unexplained) were adopted for the case definition of the surveillance. The surveillance began I week before the conference, and continued until 1 week after the conference ended. We could not detect any outbreaks during this surveillance. Compared to the existing diagnosis-based surveillance system, symptom-based surveillance has the advantages of timeliness and simplicity. However, poor specificity and difficulties in determining epidemic threshold were important limitations of this system. To increase the specificity of surveillance, it is essential to incorporate rapid laboratory diagnoses into the system.

Enhancement of osteogenesis on hydroxyapatite surface coated with synthetic peptide (EEEEEEEPRGDT) in vitro

Some dental implants are coated with hydroxyapatite (HA), which preferentially binds to bone. Several matrix proteins have an arginine-glycine-aspartic acid (RGD) sequence where cells attach via an integrin receptor. We hypothesized that coating an HA surface with an RGD-containing peptide might enhance the attachment and differentiation of osteoblasts. The HA disks (diameter 34 mm, thickness 1 mm) were treated with a solution (50 mM Tris/HCl and 150 mM NaCl, pH 7.4) containing the peptide EEEEEEEPRGDT, in which the E repetition exerts a high affinity to HA. After washing with phosphate-buffered saline, KUSA/A1 mouse osteoblastic cells were inoculated onto the HA surface and cultured. After 30 min, the number of cells attached to the surface was counted. The DNA content and alkaline phosphatase (ALP) activity were measured after 10 days in culture. Expression of bone matrix proteins was also examined by means of reverse transcriptase-polymerase chain reaction at 7 days; the mineralized area of the culture was also evaluated by staining with Alizarin Red S after 10 days. Treatment with the peptide stimulated cell attachment and increased DNA content and ALP activity. Furthermore, matrix protein expression and mineralized nodule formation were enhanced to a greater extent on the peptide-treated surface than on the nontreated surface. Our results indicate that coating an HA surface with RGD-containing peptide enhances osteoblast attachment and differentiation. This peptide treatment of HA-coated implants may stimulate the osseointegration of the implants.

The influence of altered occlusal guidance on condylar displacement

This study investigated mandibular displacement and masticatory muscle activity during clenching in lateral occlusal position in relation to the lateral occlusal pattern. Twenty healthy human subjects (mean = 26.5 years) volunteered for this study. Metallic occlusal overlays were fabricated for the lower working side canine to second molar and non-working side second molar in order to simulate a canine protected occlusion, group function occlusion and bilateral balanced occlusion (balancing contact). Three-dimensional displacements of the bilateral condyle and electromyography (EMG) activities in the bilateral masseter, anterior and posterior temporalis were recorded during maximal clenching. The experimental occlusal pattern was revealed to have statistically significant effects on both condylar displacement and EMG activity (P < 0.001 and P < 0.001, respectively). When compared to the simulated group function occlusion, the simulated canine protected occlusion and balancing contact caused statistically significant smaller superior displacements of the non-working side condyle, which suggests that they may result in reduced temporomandibular joint (TMJ) loading. Furthermore, the simulated canine protected occlusion was associated with the lowest EMG activity, which suggests that this occlusal pattern has the capacity to reduce the level of parafunctional activity.

Fracture resistance of pressable glass-ceramic fixed partial dentures

The aim of the present study was to evaluate the mechanical strength of the Empress2 system, which is based on the use of a high-strength glass--ceramic core of lithium disilicate, and the fracture resistance of fixed partial dentures fabricated with this material. To evaluate mechanical strength, four types of ceramic materials were tested for four-point flexural strength and diametral tensile strength: Empress2 core material, Empress2 layering porcelain, conventional Empress material and Dicor. Then, using Empress2, conventional Empress and Dicor, actual clinical type anterior fixed partial dentures were fabricated for fracture testing. The results showed that the Empress2 core material, at 329 MPa, has more than twice the flexural strength of conventional materials and at 271 MPa, more than four times the diametral tensile strength of conventional materials. Furthermore, fixed partial dentures fabricated with Empress2 had a fracture resistance of 1424 N. That is, they were more than twice as fracture resistant as fixed partial dentures made with conventional materials.

Digital acoustic analysis of five vowels in maxillectomy patients

The aim of the study was to characterize the acoustics of vowel articulation in maxillectomy patients. Digital acoustic analysis of five vowels, /a/, /e/, /i/, /o/ and /u/, was performed on 12 male maxillectomy patients and 12 normal male individuals. A simple set of acoustic descriptions called the first and second formant frequencies, F1 and F2, were employed and calculated based on linear predictive coding. The maxillectomy patients had a significantly lower F2 for all five vowels and a significantly higher F1 for only /i/ vowel. From the data plotted on an F1-F2 plane in each subject, we determined the F1 range and the F2 range, which are the differences between the minimum and the maximum frequencies among the five vowels. The maxillectomy patients had a significantly narrower F2 range than the normal controls. In contrast, there was no significant difference in the F1 range. These results suggest that the maxillectomy patients had difficulty in controlling F2 properly. In addition, the speech intelligibility (SI) test was performed to verify the results of this new frequency range method. A high correlation between the F2 range and the score of SI test was demonstrated, suggesting that the F2 range is effective in evaluating the speech ability of maxillectomy patients.

Coaggregation of Porphyromonas gingivalis and Prevotella intermedia

Porphyromonas gingivalis cells coaggregated with Prevotella intermedia cells. The coaggregation was inhibited with L-arginine, L-lysine, Nalpha-p-tosyl-L-lysine chloromethyl ketone, trypsin inhibitor, and leupeptin. Heat- and proteinase K-treated P. gingivalis cells showed no coaggregation with P. intermedia cells, whereas heat and proteinase K treatments of P. intermedia cells did not affect the coaggregation. The vesicles from P. gingivalis culture supernatant aggregated with P. intermedia cells, and this aggregation was also inhibited by addition of L-arginine or L-lysine and by heat treatment of the vesicles. The rgpA rgpB, rgpA kgp, rgpA rgpB kgp, and rgpA kgp hagA mutants of P. gingivalis did not coaggregate with P. intermedia. On the other hand, the fimA mutant lacking the FimA fimbriae showed coaggregation with P. intermedia as well as the wild type parent. These results strongly imply that a heat-labile and proteinous factor on the cell surface of P gingivalis, most likely the gingipain-adhesin complex, is involved in coaggregation of P. gingivalis and P. intermedia.

Vibration analysis of maxillary removable partial denture frameworks

The purpose of this study was to investigate the vibratory characteristics of three designs of the Class I Kennedy maxillary removable partial denture frameworks as the basic study. Their major connectors comprised a U-shaped palatal connector (UPC), single palatal bar (SPB), and anterior-posterior palatal bars (APB). Frequency response functions were measured when the framework was impacted. The modal shape was observed and the decay rate was calculated using modal analysis software. The results showed that the vibratory properties of each framework differed from each other. Within the range of frequencies from 10 to 2000 Hz, the UPC type had seven natural frequencies, while the SPB and the APB types had six. The UPC type had a greater number of natural modes accompanied by elastic deformation, including fluttering and twisting, than the other type, and the UPC type was considered to be unfavourable. The decay rate of the APB type was significantly higher than those of the UPC and the SPB types (P < 0.01).

Identification of two Fas-associated phosphatase-1 (FAP-1) promoters in human cancer cells

Fas-associated phosphatase-1 (FAP-1) has been reported as a negative regulator of Fas-mediated signal transduction in human cancer cells. To obtain insights into the potential carcinogenesis of the FAP-1 gene, we investigated its transcriptional regulation in normal and cancerous cells. To identify the FAP-1 promoter sequences, we first isolated P1 and cosmid clones that contained the regulatory region upstream from the FAP-1 gene by using the PCR products of 5' rapid amplification of cDNA end (5'-RACE) as probes. Genomic analysis of positive clones revealed that the major FAP-1 mRNA was transcribed from its proximal promoter (pPRM) in all human cancer cell lines tested, but 1 additional large transcript derived from its distal promoter (dPRM) was found in the human colon cancer cell line DLD-1. This suggests that the FAP-1 gene may be aberrantly dysregulated in some types of human cancers, including colon carcinoma. Sequence analysis of the region upstream from the FAP-1 gene strongly suggests that the transcript of the FAP-1 gene may be controlled by a variety of transcriptional regulatory elements, including NF-kappa B, NF-IL6, and p53 in its 2 promoters. These results imply that the FAP-1 gene may be a target gene under the control of important apoptosis-related nuclear factors in human cancers.

[Narrowing of the dental pulp cavity in patients undergoing long-term administration of steroids]

The purpose of this study was to examine narrowing of the dental pulp cavity in patients undergoing long-term administration of steroids, by means of intraoral radiographs. The subjects were 20 patients under long-term steroid treatment (the steroid group), and 15 patients who were not receiving steroids (the non-steroid group), who visited the Clinic for Persons with Disabilities, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University, between April 1994 and March 2000. The dental pulp cavity was divided into the coronal area and the root area. Narrowing of each area was classified into three stages by means of intraoral radiographs (0, none; 1, moderate; 2, severe). Maxillary and mandibular dentition was divided, for purposes of analysis, into anterior, premolar, and molar areas, respectively. The narrowing of each part was statistically compared between the steroid group and the non-steroid group, using the Mann-Whitney U-test. Mean age +/- SD of the steroid group and the non-steroid group was 50.5 +/- 17.3 and 51.8 +/- 14.1, respectively. There was no significant difference in mean age between the steroid group and the non-steroid group (t-test). Narrowing of the dental pulp cavity in the steroid group was significantly greater than in the non-steroid group, except in the root area of the molar part. Since there was no significant difference in mean age between the steroid group and the non-steroid group, the greater narrowing in the steroid group was concluded to be attributable to the long-term administration of steroids.

[Effectiveness of a new toothbrush with irrigation and suctioning capabilities (ty e-Brush) for removing supragingival plaque]

Patients with dysphagia typically have poor oral health. Because of improper swallowing, they cannot easily and safely clean their mouths. As a solution for such a problem, a manual toothbrush with both irrigation and suctioning functions has been developed, called the "e-Brush". The purpose of this study was to evaluate the cleaning effectiveness of the new e-Brush (9 mm and 11 mm in bristle length) for removing supragingival plaque, compared with a conventional toothbrush, GUM # 211 by Butler. In this study, 12 subjects (12 female of average age 20.6) were selected, and plaque control record (PCR) and scrubbing method were used. The following results were obtained: 1. Significant differences (p < 0.05) were recognized between e-Brush/9 mm (55.54 +/- 18.27%) and the others (e-Brush/11 mm: 30.88 +/- 8.14%, GUM # 211: 35.42 +/- 9.32%). 2. Bristles 9 mm in length were more effective than 11 mm bristles (p < 0.05). 3. Irrigation/suctioning function is more effective than the conventional tooth-brushing method. 4. The irrigation function of e-Brush was meritorious in making almost all users comfortable. These results suggest that this new oral hygiene device, "e-Brush/9 mm", is effective for improving oral care management for patients with dysphagia.

Masticatory mandibular movements for different foods textures related to onomatopoetic words

This study aimed to investigate the effects of different sensory-evaluated food textures on masticatory movements, and to identify meaningful factors that correspond to different food textures. Masticatory movements of three healthy subjects were evaluated with a jaw movement tracking device using five different test foods: almond, hard and light rice crackers, apple, and chewing gum. The movements of the incisor point, working and non-working condyle and the entire mandible at the occlusal phase in the horizontal plane were analyzed. For harder foods, the incisor entered the intercuspal position from a rear and lateral, the working condyle showed anterior and noticeable medial movements as the entire mandible translated posteriorly and medially. For soft foods, the incisor movements were nearly coincidental with the lateral border movements, and the mandible rotated towards the inner side near the working condyle. Although the overall paths of the mandibular movements are individually different, it appeared that jaw movement at the final closure is particular to the food texture. From the standpoint of mandibular movements, it is suggested that masticatory movements during the occlusal phase in the horizontal plane is useful for revealing the relationship between mandibular movements and food textures that were evaluated with onomatopoetic words.

Dynamic retentive force of a mandibular unilateral removable partial denture framework with a back-action clasp

PURPOSE

The purpose of this study was to investigate the dynamic retentive force of a mandibular unilateral distal-extension partial denture framework with a back-action clasp that was designed in a buccally tilted cast on a dental surveyor. The retention mechanism of this framework was analyzed in comparison with other typical unilateral and bilateral frameworks for the mandibular Kennedy class II case.

MATERIALS AND METHODS

Experimental gold alloy frameworks of three designs were repositioned to the master cast, and lifted upward to the vertical direction to the occlusal plane. The load required to dislodge each framework was recorded. The retentive force of each framework was determined by the maximum load in a dislodgment cycle. The bending strength of a plain clasp pattern of the same length as the clasp arm used in each framework was also measured by cantilever beam test.

RESULTS

The mean retentive force of the unilateral framework with a back-action clasp of relatively low bending strength was significantly higher (P < 0.01) than that of the unilateral framework with two Akers clasps of relatively high bending strength, and 70 to 80% of the bilateral framework with two Akers clasps on the edentulous side and a double Akers clasp on the contralateral side. The unilateral framework with a back-action clasp showed the greatest early load resistance in the dislodgment cycle among the three designs.

CONCLUSION

The reasonable retention mechanism was demonstrated by the unilateral framework with a back-action clasp.

Role of C-terminal region of HA-33 component of botulinum toxin in hemagglutination

Using SDS-PAGE, we found that one subcomponent, hemagglutinin (HA-33), from the Clostridium botulinum progenitor toxin of type D strain 1873 and type C strain Yoichi had slightly smaller molecular sizes than those of type C and D reference strains, but other components did not. Based on N- and C-terminal sequence analyses of HA-33, a deletion of 31 amino acid residues from the C-terminus at a specific site was observed in the HA-33 proteins of both strains. The progenitor toxins from both strains showed poor hemagglutination activities, titers of 2(1) or less, which were much lower than titers from the reference strains (2(6)), and did not bind to erythrocytes. These results suggest strongly that the short C-terminal region of the HA-33 plays an essential role in the hemagglutination activity of the botulinum progenitor toxin. Additionally, a sequence motif search predicted that the C-terminal region of HA-33 has a carbohydrate-recognition subdomain.

Rigidity of three different types of mandibular major connector through vibratory observations

PURPOSE

The purpose of this study was to investigate the vibration characteristics of three different designs of mandibular major connectors in vitro by observing modal animation, decay rate, and maximum amplitude.

MATERIALS AND METHODS

Three removable partial denture frameworks--lingual bar, Kennedy bar, and lingual plate--were studied. They were excited by a shaker, and the frequency response functions were recorded on a Fast Fourier Transformational analyzer to identify their modal shapes. Natural frequency and animation of motion at each natural mode of vibration of the three frameworks were observed. In addition, transient response simulations were recorded, and decay rates and maximum amplitude of the resultant transient response waves were computed.

RESULTS

The mean decay rate calculated from all the measurement points of the lingual bar, Kennedy bar, and lingual plate was 3.10 s-1 (standard deviation [SD] 0.07), 2.42 s-1 (SD 0.04), and 2.01 s-1 (SD 0.03), respectively. Significant differences in decay rate were found among all pairs (P < .001). Maximum amplitude of the direct and indirect retainers at the nonimpacted side also differed (P = .008).

CONCLUSION

All three designs demonstrated no elastic deformation at each natural mode of vibration. In terms of vibration analysis, the lingual bar demonstrated the maximum decay rate and the minimum maximum amplitude of the direct and indirect retainers, both on impacted and nonimpacted sides, indicating that the lingual bar will dissipate the energy through vibration faster than the other designs. Hence, the possibility of creating harmful effects to the oral tissue is lesser.

Proliferation of lung macrophages in acute fatal viral infections in chickens

Marked proliferation of macrophages engulfing yellow pigments and fragmented erythrocytes were seen in the air capillaries and blood capillaries of the lungs of chickens affected with acute fatal viral hydropericardium syndrome, highly pathogenic infectious bursal disease, and highly pathogenic avian influenza. Proliferation of lung macrophages was associated with systemic proliferation of macrophages. Acute destruction of erythrocytes in these infections may have induced systemic hyperplasia of macrophages. The acute and severe proliferation of lung macrophages may cause acute respiratory dysfunction and be one of the factors inducing mortality in infected chickens. This syndrome may be categorized as "virus-associated hemophagocytic syndrome."

Evaluation of a mass influenza vaccination campaign

Kawaura, a rural town in Kumamoto Prefecture, Japan, population approximately 6,800, started a mass influenza vaccination campaign in the 1999-2000 season for all residents > or = 3 years of age. The town provided free vaccinations to children < or = 13 years and the elderly > or = 65 years. Only 900 yen (US$8.80) was charged to the other residents for two vaccinations. In the 1999-2000 season, a total of 5,563 doses of vaccine were administered to 2,952 residents. Over 90% of the vaccinees received two doses. The program resulted in a vaccination rate of 43% of all residents. The vaccination rates for females and males were 40.7% and 36.8%, and for those of 3-14 years, 15-64 years, and > or = 65 years population were 75%, 31%, and 55%, respectively. The town spent a total of 5.78 million yen (US$56,700) for the campaign. The per-shot cost was estimated as 1,683 yen (US$16.50). From December 1999 through March 2000, a total of 233 town residents (15-101 years old, median 72) were admitted to the town hospital. Of the 233 inpatients, 22 (66-98 years old, median 78) developed respiratory illness, with 4 fatal outcomes. Of these 22 cases, 3 had been vaccinated twice, while 19 had not been vaccinated at all. The relative risk of vaccinees' hospitalization due to respiratory illness decreased to 0.13 compared with that of non-vaccinees (3/1,203 versus 19/1,003, vaccine efficacy = 0.87). Likewise, the relative risk of vaccinees death due to respiratory illness decreased to 0.28 compared with that of non-vaccinees (1/1,203 versus 3/1,003). The results of the Kawaura town's initiative should be helpful for better modeling of mass influenza vaccination campaigns.