Endotoxin activity and leukocytic STAT3 mRNA alterations differ according to age in lipopolysaccharide-challenged calves.

The objective of this study was to investigate the age difference in the response to endotoxin in calves related to the plasma endotoxin activity and mRNA expression of cytokines. Fifteen calves were divided into three groups: control (191 ± 21 days), weaning (162.4 ± 17.5 days), and calf (22.4 ± 8.2 days). The weaning and calf groups received 2.5 µg/kg of ultrapure O111:B4 LPS in 10 mL of each autologous serum, whereas the control calves received a similar volume of saline. Blood samples were collected at 0, 0.5, 1, 2, 4, 8, 12, and 24 h. Liver samples were collected by ultrasound-guided liver biopsy at 0, 2, 4, and 24 h. Plasma endotoxin activity was measured by the limulus amebocyte lysate kinetic turbidimetric assay. The mRNA expression level of GAPDH, TLR-4, NF-κB2, TNF-α, IL-6, and STAT3 in leukocytes and the liver was measured by real-time PCR. Following LPS challenge, the maximal plasma endotoxin activity, and leukocytic expression of TLR4, NF-κB2, TNF-α, and STAT3 were reached at 0.5, 4, 2-4, 2-4, and 4 h, respectively, in weaning and calf groups. The endotoxin activity in calf remained high until 2 h. Furthermore, the expression of leukocytic STAT3 mRNA in calf was not significantly different from the pre-value. In contrast, STAT3 mRNA in weaning markedly increased at 2 and 4 h. Therefore, this study provides new information to the literature of immune and inflammatory responses in calves.

Subjective Evaluation of Denture Adhesives: A Multicenter Randomized Controlled Trial.

INTRODUCTION: Many reports show that denture adhesives improve the retention and stability of dentures. However, few randomized controlled trials have examined the effects of denture adhesives. OBJECTIVE: This 10-center randomized controlled trial with parallel groups involving 200 edentulous patients wearing complete dentures aimed to evaluate the effects of short-term use of cream and powder denture adhesives. METHODS: Patients were allocated into 2 cream- and powder-type adhesive groups and 1 control group. Intervention groups were treated with the 2 adhesives (1 each), and the control group received saline solution. Adhesive or control was applied to the denture-mucosal surface for 4 d, and data at baseline and after day 4 of intervention (i.e., 8 meals) were obtained. Patient satisfaction was evaluated with a 100-mm visual analog scale. Oral health-related quality of life was measured with the Japanese version of the Oral Health Impact Profile for Edentulous Patients. Perceived chewing ability was evaluated by a questionnaire regarding ease of chewing and swallowing food. Between-group comparisons were performed with Kruskal-Wallis tests with the Mann-Whitney U test adjusted by Bonferroni correction. Within-group comparisons of pre- and postintervention measurements were performed with the Wilcoxon signed-rank test. Intention-to-treat analysis was also performed. RESULTS: Between-group comparisons showed no significant differences for general satisfaction or Oral Health Impact Profile for Edentulous Patients. However, significant differences in satisfaction with various denture functions with cream- and powder-type adhesives were seen in pre- and postintervention comparisons (P < 0.05). Significant differences were also observed for perceived chewing ability of hard foods (P < 0.05). CONCLUSION: These results suggest that although denture adhesives do not invariably improve denture function, they do affect subjective evaluations and possibly chewing of hard foods. Therefore, the effects of denture adhesive use are insufficient to resolve any fundamental dissatisfaction with dentures ( ClinicalTrials.gov NCT01712802 ). KNOWLEDGE TRANSFER STATEMENT: The results of this study suggest that denture adhesives should be applied under certain conditions; however, an appropriate diagnosis is important before application. These practice-based data provide information to establish evidence-based guidelines for applying denture adhesives.

Molecular and clinical characterization of glucokinase maturity-onset diabetes of the young (GCK-MODY) in Japanese patients.

AIMS: To investigate the molecular and clinical characteristics of the largest series of Japanese patients with glucokinase maturity-onset diabetes of the young (GCK-MODY), and to find any features specific to Asian people. METHODS: We enrolled 78 Japanese patients with GCK-MODY from 41 families (55 probands diagnosed at the age of 0-14 years and their 23 adult family members). Mutations were identified by direct sequencing or multiplex ligation-dependent probe amplification of all exons of the GCK gene. Detailed clinical and laboratory data were collected on the probands using questionnaires, which were sent to the treating physicians.　Data on current clinical status and HbA1c levels were also collected from adult patients. RESULTS: A total of 35 different mutations were identified, of which seven were novel. Fasting blood glucose and HbA1c levels of the probands were ≤9.3 mmol/l and ≤56 mmol/mol (7.3%), respectively, and there was considerable variation in their BMI percentiles (0.4-96.2). In total, 25% of the probands had elevated homeostatic assessment of insulin resistance values, and 58.3% of these had evidence of concomitant Type 2 diabetes in their family. The HbA1c levels for adults were slightly higher, up to 61 mmol/mol (7.8%). The incidence of microvascular complications was low. Out of these 78 people with GCK-MODY and 40 additional family members with hyperglycaemia whose genetic status was unknown, only one had diabetic nephropathy. CONCLUSIONS: The molecular and clinical features of GCK-MODY in Japanese people are similar to those of other ethnic populations; however, making a diagnosis of GCK-MODY was more challenging in patients with signs of insulin resistance.

Multi-level control of conductive nano-filament evolution in HfO2 ReRAM by pulse-train operations.

Precise electrical manipulation of nanoscale defects such as vacancy nano-filaments is highly desired for the multi-level control of ReRAM. In this paper we present a systematic investigation on the pulse-train operation scheme for reliable multi-level control of conductive filament evolution. By applying the pulse-train scheme to a 3 bit per cell HfO2 ReRAM, the relative standard deviations of resistance levels are improved up to 80% compared to the single-pulse scheme. The observed exponential relationship between the saturated resistance and the pulse amplitude provides evidence for the gap-formation model of the filament-rupture process.

Posterior capsule opacification following 20- and 23-gauge phacovitrectomy (posterior capsule opacification following phacovitrectomy).

PURPOSE: To compare the development of posterior capsule opacification (PCO) for idiopathic epi-retinal membrane cases between 20- and 23-gauge phacovitrectomy. METHODS: Cataract surgery of phacoemulsification with the SA60AT implantation and 20- or 23-gauge vitrectomy was performed for 20 patients in both groups. Cataract surgery alone was performed for 50 patients as the control. The PCO density values were measured using Scheimpflug video photography at 1 week, 1, 3, 6, 12, 18, and 24 months after surgery. The number of eyes that required Nd:YAG laser capsulotomy was also examined. RESULTS: The mean PCO value in the 20-gauge phacovitrectomy group increased significantly with time (P<0.001), whereas those in the 23-gauge phacovitrectomy group and the cataract surgery group did not show any significant change. Furthermore, the PCO value in the 20-gauge phacovitrectomy group was significantly greater than that in the 23-gauge phacovitrectomy group at 6, 12, 18 (P<0.05), and 24 months (P<0.01) after surgery. The PCO value in the 23-gauge phacovitrectomy group was significantly greater than that in the cataract surgery group 24 months after surgery (P<0.05). The rate of capsulotomy in the 20-gauge phacovitrectomy group was significantly higher than that in the cataract surgery group (P=0.007), whereas there was no significant difference between the 23-gauge phacovitrectomy group and the cataract surgery group. CONCLUSION: PCO rate in eyes with the 23-gauge phacovitrectomy was lower than in those with the 20-gauge phacovitrectomy, and PCO rate even in the 23-gauge phacovitrectomy was higher than in those with cataract surgery.

Histopathological manifestations of membranoproliferative glomerulonephritis and glomerular expression of plasmalemmal vesicle-associated protein-1 in a patient with polycythemia vera.

Only a few cases of various glomerulonephropathies have been reported in patients with polycythemia vera. We report the case of a 72-year-old female with polycythemia vera in whom renal biopsy examination showed membranoproliferative glomerulonephritis (MPGN)-like lesion and glomerular expression of plasmalemmal vesicle-associated protein-1 (PV-1), a marker of glomerular capillary remodeling after injury. Prior to admission to our hospital for nephrotic syndrome, she had received hydroxyurea and phlebotomy. On admission, she was hypertensive with pretibial edema, hepatosplenomegaly, massive proteinuria (6.14 g/day), low serum albumin (2.9 g/dl), high fibrinogen, fibrin/fibrinogen degradation products and thrombomodulin levels, but with normal serum creatinine and complement levels. Microscopic examination of a renal biopsy demonstrated MPGN-like features with double contour and mesangial interposition. Electron microscopy showed subendothelial deposits, platelets attached to glomerular capillary walls and fibrin deposition. Immunofluorescence study identified IgM deposition along part of the capillary wall and mesangium. CD42b-positive platelets and megakaryocytes were detected in glomerular capillaries, accompanied with increased expression of platelet-derived growth factor receptor b and thrombomodulin in the mesangium and glomerular capillary, respectively. PV-1 was expressed along the glomerular capillary. Anti-platelet and anticoagulant combination therapy, together with the use of anti-hypertensive agents and hydroxyurea, resulted in improvement of the nephrotic syndrome. The findings suggested that activated platelets, enhanced coagulation state and endothelial damage may contribute to glomerulonephropathy associated with polycythemia vera.

Dynamics of placental ghrelin production and its receptor expression in a Dahl salt-sensitive rat model of intrauterine growth restriction.

BACKGROUND: Ghrelin, a peptide hormone produced mainly in the stomach, is an endogenous ligand for the growth hormone secretagogue receptor (GHS-R). The existence of placental ghrelin and its receptor has been confirmed in normal pregnancy. However, few reports have so far referred to placental ghrelin and its receptor in intrauterine growth restriction (IUGR). OBJECTIVES: The dynamics of ghrelin production and its receptor expression was investigated to clarify the role of placental ghrelin in an IUGR pregnancy using pregnant Dahl salt-sensitive (Dahl S) rats as a model for IUGR. METHODS: Pregnant Dahl S rats were fed a high-salt diet to develop hypertensive pregnancy with IUGR (IUGR-preg). The levels of ghrelin peptide in the placenta, stomach and plasma of the dams, together with the expression levels of mRNAs for ghrelin and its functional receptor (GHS-R1a) in the placenta, were measured in the IUGR-preg rats at 2 and 3 weeks of gestation, and compared to those in the control pregnant Dahl S rats fed standard chow (Normal-preg). RESULTS: The levels of placental ghrelin peptide at 2 weeks of gestation and placental ghrelin mRNA at each gestational week in IUGR-preg were significantly higher than those in Normal-preg. The level of GHS-R1a mRNA in the placenta of IUGR-preg, which was lower at 2 weeks of gestation in comparison to Normal-preg, significantly increased from 2 to 3 weeks of gestation. No significant difference was observed in the level of ghrelin peptide in the plasma or stomach of the dams between the two groups. CONCLUSION: The profile of placental ghrelin production and the expression of its receptor using Dhal S rats in the IUGR-preg was different from that in the control. The placental ghrelin-ghrelin receptor system thus continues to work until the term of pregnancy in the IUGR-preg in contrast to Normal-preg, which might act as a compensational mechanism for fetal growth.

Peripherally administered ghrelin induces bimodal effects on the mesolimbic dopamine system depending on food-consumptive states.

Ghrelin induces orexigenic behavior by activation of growth hormone secretagogue 1 receptors (GHSRs) in the ventral tegmental area (VTA) as well as hypothalamus, suggesting the involvement of mesolimbic dopamine system in the action of ghrelin. The present study aimed to identify neuronal mechanisms by which peripherally administered ghrelin regulates the mesolimbic dopamine system under different food-consumptive states. Ghrelin was administered to rats peripherally (3 nmol, i.v.) as well as locally into the VTA (0.3 nmol). Dopamine in the nucleus accumbens shell (NAc) was measured by microdialysis. Peripheral administration of ghrelin decreased dopamine levels in the NAc when food was removed following ghrelin administration. This inhibitory effect was mediated through GABA(A) and N-methyl-D-aspartate (NMDA) receptors in the VTA. In contrast, when animals consumed food following ghrelin administration, dopamine levels increased robustly. This stimulatory effect was mediated through NMDA receptors, but not through GABA(A) receptors, in the VTA. Importantly, both the inhibitory and stimulatory effects of ghrelin primarily required activation of GHSRs in the VTA. Furthermore, local injection of ghrelin into the VTA induced dopamine release in the NAc and food consumption, supporting the local action of ghrelin in the VTA. In conclusion, peripherally administered ghrelin activates GHSRs in the VTA, and induces bimodal effects on mesolimbic dopamine neurotransmission depending on food-consumptive states.

TRAIL pathway components and their putative role in granulosa cell apoptosis in the human ovary.

Extensive apoptotic oocyte reduction occurs during fetal ovarian development. The regulatory pathways responsible for oocyte selection to programmed cell death are, however, poorly understood. The aim of this study was to investigate the potential involvement of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and its death receptors TRAIL-R1/DR4 and TRAIL-R2/DR5 and decoy receptors TRAIL-R3/DcR1 and TRAIL-R4/DcR2 in the apoptotic process characterizing human fetal and adult ovaries. For this purpose, in situ hybridization and immunohistochemistry were applied to human fetal and adult ovarian samples to study the mRNA and protein expression of TRAIL pathway components, and a human granulosa cell tumor-derived cell line (KGN) was used to elucidate functional effects of TRAIL on apoptosis. TRAIL was expressed in human fetal ovary from the 11th week until term. The pro-apoptotic TRAIL-R2/DR5 and the anti-apoptotic TRAIL-R4/DcR2 were also expressed in human ovaries throughout the fetal period. Among the different ovarian cell types, these TRAIL pathway components were mainly localized in the oocytes, and their expression increased towards term. Expression of TRAIL-R1/DR4 and TRAIL-R3/DcR1 was negligible in all of the fetal ovaries studied. Adult ovaries expressed TRAIL, TRAIL-R2/DR5, TRAIL-R3/DcR1 and TRAIL-R4/DcR2 in granulosa cells and oocytes of small primary/secondary follicles as well as in granulosa and theca cells of more developed antral follicles. In KGN cells, TRAIL efficiently induced apoptosis in a dose-dependent manner, and this was blocked by a caspase inhibitor. The results indicate a role of the TRAIL pathway components in the regulation of granulosa cell apoptosis in in vitro and suggest that these factors may have a role in regulating ovarian apoptosis also in vivo.

Environmental control in tea fields to reduce infection by Pseudomonas syringae pv. theae.

Bacterial shoot blight (BSB) disease, caused by Pseudomonas syringae pv. theae, is a major bacterial disease of tea plants in Japan. BSB mainly occurs in the low-temperature season, and lesion formation by P. syringae pv. theae is enhanced by both low temperature and the presence of ice nucleation-active Xanthomonas campestris (INAX), which catalyzes ice formation at -2 to -4 degrees C and is frequently co-isolated with P. syringae pv. theae from tea plants. Low temperature is thus the most important environmental factor influencing the incidence of BSB; however, the effects of low temperature on infection of the host by P. syringae pv. theae and of environmental controls in fields on the occurrence of the disease are poorly understood. In this study, we show that ice formation on tea leaves by INAX enhanced P. syringae pv. theae invasion into leaf tissue. The natural incidence of BSB in the field was closely related to early autumn frost. Frost protection in late autumn, which prevented ice formation on tea plants, significantly decreased the incidence of BSB, and frost protection combined with bactericide application held the incidence under the economic threshold level. Our data indicate that environmental control in the field based on microbial interactions in the host offers a new strategy for plant disease control.

Noise characteristics of the Fano effect and the Fano-Kondo effect in triple quantum dots.

We theoretically compare transport properties of the Fano-Kondo effect with those of the Fano effect, focusing on the effect of a two-level state in a triple quantum dot (QD) system. We analyze shot noise characteristics in the Fano-Kondo region at zero temperature, and discuss the effect of strong electronic correlation in QDs. We found that the modulation of the Fano dip is strongly affected by the on-site Coulomb interaction in QDs, and stronger Coulomb interaction (Fano-Kondo case) induces larger noise.

Effect of different labio-lingual spaces in tray designs on the displacement of and pressure against a mobile tooth.

The present study aimed to examine the effect of custom tray designs on the displacement of mobile tooth and local impression pressures during the impression procedure, using partially edentulous simulation models with six anterior teeth containing a mobile tooth prepared in previous studies. The custom trays were designed by altering the thickness of the respective spaces on the labial and lingual sides of the remaining tooth arch. In previous studies, the mobile tooth was displaced in the labial direction and local impression pressures of the mobile tooth were greater against the lingual side than the labial side for all custom tray designs. Furthermore, the custom trays perforated with holes on the lingual side were effective to reduce mobile tooth displacement, labial and lingual impression pressures against the mobile tooth, and the differences between them. Therefore, the present study was performed focusing on the labial and lingual thickness of spaces in custom tray designs. It was found that mobile tooth displacement, labial and lingual impression pressures against the mobile teeth and their differences were less in trays with spaces>3.0 mm thick on both the labial and lingual sides, but markedly greater in trays with a 1.5 mm-thick space on the labial side. These results indicate that the thickness of spaces on the labial side in the tray should not be reduced to prevent mobile tooth displacement.

Src activation generates reactive oxygen species and impairs metabolism-secretion coupling in diabetic Goto-Kakizaki and ouabain-treated rat pancreatic islets.

AIMS/HYPOTHESIS: Na(+)/K(+)-ATPase inhibition by ouabain suppresses ATP production by generating reactive oxygen species (ROS) and impairs glucose-induced insulin secretion from pancreatic islets. To clarify the signal-transducing function of Na(+)/K(+)-ATPase in decreasing ATP production by the generation of ROS in pancreatic islets, the involvement of Src was examined. In addition, the significance of Src activation in diabetic islets was examined. METHODS: Isolated islets from Wistar rats and diabetic Goto-Kakizaki (GK) rats (a model for diabetes) were used. ROS was measured by 5-(and 6)-chloromethyl-2',7'-dichlorofluorescein fluorescence using dispersed islet cells. After lysates were immunoprecipitated by anti-Src antibody, immunoblotting was performed. RESULTS: Ouabain caused a rapid Tyr(418) phosphorylation, indicating activation of Src in the presence of high glucose. The specific Src inhibitor 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2) restored the ouabain-induced decrease in ATP content and the increase in ROS production. Both PP2 and ROS scavenger restored the impaired insulin release and impaired ATP elevation in GK islets, but had no such effect in control islets. PP2 reduced the high glucose-induced increase in ROS generation in GK islet cells but had no effect on that in control islet cells. Moreover, ouabain had no effect on ATP content and ROS production in the presence of high glucose in GK islets. CONCLUSIONS/INTERPRETATION: These results indicate that Src plays a role in the signal-transducing function of Na(+)/K(+)-ATPase, in which ROS generation decreases ATP production in control islets. Moreover, ROS generated by Src activation plays an important role in impaired glucose-induced insulin secretion in GK islets, in which Src is endogenously activated independently of ouabain.

Endoscope disinfection using chlorine dioxide in an automated washer-disinfector.

Although 2% glutaraldehyde is often the first-line agent for endoscopic disinfection, its adverse reactions are common among staff and it is less effective against certain mycobacteria and spore-bearing bacteria. Chlorine dioxide is a possible alternative and an automated washer-disinfector fitted with this agent is currently available. This study was conducted to evaluate the effectiveness of chlorine dioxide in endoscopic disinfection after upper gastrointestinal examination. In vitro microbicidal properties of chlorine dioxide solutions were examined at high (600 ppm) and low (30 ppm) concentrations against various microbes including Pseudomonas aeruginosa, Helicobacter pylori, Mycobacterium avium-intracellulare and Bacillus subtilis in the presence or absence of bovine serum albumin (BSA). Immediately following endoscopic procedures and after application to the automated reprocessor incorporating chlorine dioxide at 30 ppm for 5 min, endoscopic contamination with infectious agents, blood, H. pylori ureA gene DNA and HCV-RNA was assessed by cultivation, sensitive test tape, polymerase chain reaction (PCR) and reverse transcriptase-PCR analysis, respectively. Chlorine dioxide at 30 ppm has equivalent microbicidal activity against most microbes and faster antimicrobial effects on M. avium-intracellulare and B. subtilis compared with 2% glutaraldehyde, but contamination with BSA affected the microbicidal properties of chlorine dioxide. Endoscopic contamination with microbes, blood and bacterial DNA was eliminated after application of the automated reprocessor/chlorine dioxide system. Thus, chlorine dioxide is a potential alternative to glutaraldehyde. The use of automated reprocessors with compatibility to chlorine dioxide, coupled with thorough pre-cleaning, can offer effective, faster and less problematic endoscopic disinfection.

Effect of corosolic acid on postchallenge plasma glucose levels.

Corosolic acid (CRA) is a substance extracted from Lagerstroemia speciosa L. and has been reported to have biological activities in in vitro and experimental animal studies. In this study, 31 subjects were orally administered 10mg CRA or a placebo, on different occasions, in a capsule 5min before the 75-g oral glucose tolerance test (OGTT) in a double-blind and cross-over design. Nineteen subjects had diabetes, seven had impaired glucose tolerance, one had impaired fasting glucose, and four had normal glucose tolerance according to the 1998 WHO criteria. There were no significant differences in plasma glucose levels before and 30min after the administration. CRA treatment subjects showed lower glucose levels from 60min until 120min and reached statistical significance at 90min. In this study, we have shown for the first time that CRA has a lowering effect on postchallenge plasma glucose levels in vivo in humans.

Closed reduction for traumatic posterior dislocation of the shoulder using the 'lever principle': two case reports and a review of the literature.

Traumatic posterior dislocation of the shoulder is frequently missed because of its rarity and the absence of characteristic symptoms. Several signs should be emphasised: an overlap of the humeral head and glenoid rim in a true anteroposterior view and the light-bulb sign in the anteroposterior view. To make an accurate and early diagnosis, use of multidirectional radiographs combined with computed tomography is recommended. Closed reduction was successfully performed under general anaesthesia using the DePalma method with slight modification--the lever principle--by pushing the medial side of the upper arm laterally to adduct the shoulder as far as possible. The dynamics of the lever principle make it a safer and more effective method of achieving a closed reduction of a posterior dislocation of the shoulder than the conventional method of solely pushing the humeral head anteriorly, especially in patients with locking of the glenohumeral joint and impression fractures.

Two states of the triple helix in the thermal transition of the collagen model peptide (Pro-Pro-Gly)10.

The collagen model peptide (Pro-Pro-Gly)10 is known to fold into a triple helix in solution. So far, the triple helix has been considered to exist as a single state. However, our previous study of (Pro-Pro-Gly)10 in solution has indicated the presence of two different states of the triple helix, a lower (HL) and a higher temperature state (HH). In the present study, these triple-helical states were investigated in more detail by NMR. Complete stereospecific assignments of the methylene protons of the proline residues were accomplished by the use of NOESY and TOCSY spectra. The temperature dependence of the 1H chemical shifts showed that the HL-to-HH thermal transition can be attributed to a conformational change of the first proline (Pro1) residues of the (Pro-Pro-Gly) triplets. Since TOCSY spectra with a 10 ms mixing-time confirmed a down puckering of these Pro residues in the HL state, but interconverting down and up puckerings in the HH state, the HL-to-HH thermal transition corresponds to conformational changes of the pyrrolidine rings of the Pro1 residues from an uniform down puckering to a more flexible state. The results confirm that thermal unfolding of the triple helix proceeds through the intermediate HH state.

Elastase-induced changes in lung function: relationship to morphometry and effect of drugs.

Intratracheal administration of porcine pancreatic elastase (PPE) produced a dose related decline in lung function, as assessed by changes in dynamic lung compliance (C(dyn)) in New Zealand White rabbits. This occurred within 24 h of administration and persisted for 56 days (n=6). These lung function changes were accompanied by histological evidence of emphysema in the lungs and were not mimicked by intratracheal administration of the proteolytic enzyme trypsin. Neither the lung function nor the histological changes induced by elastase could be prevented or reversed by either the glucocorticosteroid, dexamethasone, or all trans retinoic acid (ATRA).Our data suggest that local administration of elastase to the lungs of rabbits may provide a convenient way to assess the effects of drugs on the changes induced by elastase in airways.

Dynamic viscoelastic properties of commercial glass-fibre reinforced resin used for crowns and bridges.

In order to investigate the thermal stability, the physical and mechanical, and dynamic viscoelastic properties of glass-fibre reinforced composite materials were measured. The G' of the seven materials examined was within 5;20 +/- 14; 55 and 4;50-14; 35 GPa for dry and wet specimens in air at 37 degrees C, respectively, and decreased with increasing temperature. The G' values of dry specimens decreased by 7;74-15;4% when heated to 60 degrees C. The value of tan delta ranged from 0;0102 to 0;0295 and from 0.0181 to 0.0406 for dry and wet specimens in air at 37 degrees C, respectively. The coefficient of linear thermal expansion between 30 and 60 degrees C ranged from 0;557 to 3; 95 x 10-5/ degrees C. Moreover, the filler content ranged from 56; 36 to 88; 87 wt%. These results showed that the magnitudes of G', tan delta, and the coefficient of linear thermal expansion and water absorption depend on the inorganic filler or glass-fibre content; i.e. the amount of resin matrix. Moreover, for all the materials examined, the G' values were thermostable in the temperature range encountered in the oral cavity.

Computational 3-D modeling and site-directed mutation of an antibody that binds Neu2en5Ac, a transition state analogue of a sialic acid.

An antibody against a transition state analog (TSA) may share some common features with an enzyme that produces such a transition state. SIC172 antibody binds specifically to Neu2en5Ac, a TSA of Neu5Ac in the sialidase reaction, but has no catalytic activity. To understand how the antibody recognizes Neu2en5Ac and to find out if it is possible to convert it to a catalytic antibody, we made and sequenced the SIC172 ScFv, and constructed a 3-D model of it. The VH-CDR3 contains a unique sequence with Cys at H95. The 3-D model showed that Cys-H95 is exposed inside the antigen-binding cavity. After affinity docking, 4 types emerged. In type I, the carboxyl group of Neu2en5Ac is located near the Cys-H95 and neighboring positively charged residues. The change of Cys-H95 to Asp by site-directed mutation decreased the binding activity, while a change to Arg did not. These and other mutation experiments, and further modeling of mutant Fv, support the 3-D model and docking type I. A comparison with sialidase indicates that SIC172 antibody appears to have some groups of residues that are conserved at the active site of the enzyme. The possibility of Neu2en5Ac-binding antibody being converted to a catalytic antibody is discussed.