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We propose a new methodology for identifying and estimating demand in differentiated products models when demand and cost data are available. The method deals with the endogeneity of prices to demand shocks and the endogeneity of outputs to cost shocks by using cost data rather than instruments. Further, we allow for unobserved market size. Using Monte Carlo experiments, we show that our method works well in contexts where commonly used instruments are invalid. We also apply our method to the estimation of deposit demand in the US banking industry.

This study was designed to evaluate the cariogenic potential of Lactobacillus gasseri YIT 12321.L. gasseri YIT 12321 was isolated from the human oral cavity as a probiotic candidate strain. Three types of experimental biofilm formations on bovine enamel specimens were assessed using Streptococcus sobrinus ATCC 33478, L. gasseri YIT 12321, and a co-culture of S. sobrinus and L. gasseri YIT 12321 in vitro. L. gasseri YIT 12321 was analyzed for its ability to utilize seven carbohydrates. L. gasseri YIT 12321 was cultured in tryptic soy broth without dextrose and containing a test carbohydrate at 37 °C for 16 h.The decrease in pH in the region under the biofilm produced by L. gasseri YIT 12321 was unusually slow, and the pH was maintained above 5.5 for 16 h. The amount of biofilm and the reduction in enamel hardness were minimal in the L. gasseri YIT 12321 group among the three experimental groups. The amount of co-culture-derived biofilms was less than that of S. sobrinus biofilms. When S. sobrinus was grown using sucrose, the pH decreased to 3.98. In contrast, L. gasseri YIT 12321 cultures maintained the pH above the critical pH for dentin demineralization.L. gasseri YIT 12321 is suggested to have a low cariogenic potential. The application of this strain as a probiotic may contribute to oral safety.

Streptococcus troglodytae TKU31 was isolated from the oral cavity of a chimpanzee (Pan troglodytes) and was found to be the most closely related species of the mutans group streptococci to Streptococcus mutans. The complete sequence of TKU31 genome consists of a single circular chromosome that is 2,097,874 base pairs long and has a G + C content of 37.18%. It possesses 2082 coding sequences (CDSs), 65 tRNAs and five rRNA operons (15 rRNAs). Two clustered regularly interspaced short palindromic repeats, six insertion sequences and two predicted prophage elements were identified. The genome of TKU31 harbors some putative virulence associated genes, including gtfB, gtfC and gtfD genes encoding glucosyltransferase and gbpA, gbpB, gbpC and gbpD genes encoding glucan-binding cell wall-anchored protein. The deduced amino acid identity of the rhamnose-glucose polysaccharide F gene (rgpF), which is one of the serotype determinants, is 91% identical with that of S. mutans LJ23 (serotype k) strain. However, two other virulence-associated genes cnm and cbm, which encode the collagen-binding proteins, were not found in the TKU31 genome. The complete genome sequence of S. troglodytae TKU31 has been deposited at DDBJ/European Nucleotide Archive/GenBank under the accession no. AP014612.

第68回日本口腔衛生学会・総会; 2019.5.22-24；大津

Background of the study: Detection of the opportunistic microorganisms can be the indicator for

Lactobacillus crispatus YIT 12319 (LcY) was isolated from the oral cavity of a healthy subject as a new candidate probiotic with potential benefits for oral health. As a safety assessment of LcY, we performed an antibiotic susceptibility test and virulence-associated gene analysis using a draft genome sequence. Susceptibility to 15 antibiotics was analyzed according to the standard method of the International Dairy Federation/International Organization for Standardization, as recommended by the European Food Safety Authority. The results showed that the minimum inhibitory concentrations of LcY were not higher than those of other L. crispatus strains, which have not acquired resistance to any antibiotics, suggesting that LcY had no externally acquired transmissible antibiotic resistance genes. Analysis of virulence-associated genes using the draft genome of LcY found that there were fewer potential virulence-associated genes in LcY than in other probiotics. These findings suggest that LcY could be a candidate probiotic based on its safety profile.

© 2018 Japanese Economic Association In this paper, we survey the empirical analysis of brands. The difficulty in this area of research is that even though a brand is easily identifiable, its economic roles are not directly observable. We first discuss methods where the effect of a brand is measured as the unobservable component of sales or price of a product, which researchers recover as a residual of the sales or price regression. We then describe the approaches to estimate the various roles of brands, such as providing information and increasing the utility of consumption. Finally, we provide examples of research that highlight the role of brands in exploiting the irrationality of consumers for profit.

We estimate the effects of active labor market policies on men’s crime. To do this, we exploit a local policy change in Denmark that targeted unemployed people without unemployment insurance. Our results show that crime rates decreased among treated men relative to both untreated unemployment insured and uninsured men. Lower property crime accounted for the decrease in overall crime. Increased earnings from higher employment rates cannot explain the decrease in crime. Instead, participation in the active labor market program reduced young men’s propensity to commit crime. The results suggest that active labor market programs have substantial secondary effects on criminality.

Objective A 50-100-mg rectal dose of nonsteroidal anti-inflammatory drugs (NSAIDs; diclofenac or indomethacin) has been shown to prevent post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). However, this is higher than the recommended 25-mg dose that is commonly administered to Japanese patients. The objective of this study was to evaluate the safety and efficacy of 25-mg rectal dose of diclofenac in preventing PEP. Methods Between January 2016 and March 2017, a total of 147 patients underwent ERCP with or without the rectal administration of diclofenac (25 mg) 20 min before the procedure. A retrospective analysis was conducted to evaluate the efficacy and safety of this dose in preventing PEP. Results Thirteen patients (8.8%) developed PEP: 3 patients (4.1%) in the diclofenac group and 10 (13.7%) in the control group (p=0.0460). After ERCP, there were no cases of gastrointestinal hemorrhage, ulceration, acute renal failure, or death. A multivariate logistic regression analysis revealed that the non-administration of rectal diclofenac was a risk factor for PEP (odds ratio=3.530; 95% confidence interval=1.017-16.35; p=0.0468). Conclusions A 25-mg rectal dose of diclofenac might prevent PEP.

© 2018 The Authors Previous studies find significant negative effects of cancer on employment, with stronger effects for less-educated workers. We investigate whether the effect of cancer varies by skill requirement in the pre-cancer occupation, whether such heterogeneity can explain educational gradients, and whether cancer is associated with changes in job characteristics for cancer survivors who remain employed four years after the diagnosis. We combine Danish administrative registers with detailed skill requirement data and use individuals without cancer as a control group. Our main findings are the following: the negative effect of cancer on employment is stronger if the pre-cancer occupation requires high levels of manual skills or low levels of cognitive skills; the educational gradient diminishes substantially if we allow the effects of cancer to also depend on pre-cancer skill requirements; and cancer is not associated with occupational mobility, indicating potential for policies that reduce labour market frictions for cancer survivors.

Three strains TKU9, TKU49 and TKU50(T) , were isolated from the oral cavities of chimpanzees (Pan troglodytes). The isolates were all gram-positive, facultative anaerobic cocci that lacked catalase activity. Analysis of partial 16S rRNA gene sequences showed that the most closely related species was Streptococcus infantis (96.7%). The next most closely related species to the isolates were S. rubneri, S. mitis, S. peroris and S. australis (96.6 to 96.4%). Based on the rpoB and gyrB gene sequences, TKU50(T) was clustered with other member of the mitis group. Enzyme activity and sugar fermentation patterns differentiated this novel bacterium from other members of the mitis group streptococci. The DNA G + C content of strain TKU50(T) was 46.7 mol%, which is the highest reported value for members of the mitis group (40-46 mol%). On the basis of the phenotypic characterization, partial 16S rRNA gene and sequences data for two housekeeping gene (gyrB and rpoB), we propose a novel taxa, S. panodentis for TKU 50(T) (type strain = CM 30579(T) = DSM 29921(T) ), for these newly described isolates.

Water-insoluble glucan (WIG) produced by mutans streptococci, an important cariogenic pathogen, plays an important role in the formation of dental biofilm and adhesion of biofilm to tooth surfaces. Glucanohydrolases, such as mutanase (α-1,3-glucanase) and dextranase (α-1,6-glucanase), are able to hydrolyze WIG. The purposes of this study were to construct bi-functional chimeric glucanase, composed of mutanase and dextranase, and to examine the effects of this chimeric glucanase on the formation and decomposition of biofilm. The mutanase gene from Paenibacillus humicus NA1123 and the dextranase gene from Streptococcus mutans ATCC 25175 were cloned and ligated into a pE-SUMOstar Amp plasmid vector. The resultant his-tagged fusion chimeric glucanase was expressed in Escherichia coli BL21 (DE3) and partially purified. The effects of chimeric glucanase on the formation and decomposition of biofilm formed on a glass surface by Streptococcus sobrinus 6715 glucosyltransferases were then examined. This biofilm was fractionated into firmly adherent, loosely adherent, and non-adherent WIG fractions. Amounts of WIG in each fraction were determined by a phenol-sulfuric acid method, and reducing sugars were quantified by the Somogyi-Nelson method. Chimeric glucanase reduced the formation of the total amount of WIG in a dose-dependent manner, and significant reductions of WIG in the adherent fraction were observed. Moreover, the chimeric glucanase was able to decompose biofilm, being 4.1 times more effective at glucan inhibition of biofilm formation than a mixture of dextranase and mutanase. These results suggest that the chimeric glucanase is useful for prevention of dental biofilm formation.

Background and Objective Potentially significant associations between metabolic syndrome (MetS) and periodontal disease have been reported in recent studies; however, there is a dearth of literature regarding the relationship of MetS with serum antibody levels to periodontal pathogens. The aim of this cross-sectional study was to investigate the association between MetS and serum antibody to the periodontal pathogen Porphyromonas gingivalis (P. gingivalis) in 216 Japanese individuals aged 79 years. Materials and Methods Serum antibody levels to P. gingivalis were measured by enzyme-linked immunosorbent assay. An elevated serum antibody response was defined as the upper quartile and was considered as the outcome variable. A multivariable logistic regression model was used to evaluate the association of MetS defined by the modified National Cholesterol Education Program Adult Treatment Panel III criteria with an elevated antibody status. Adjustments for gender, income, education, smoking status, dental-care utilisation patterns and brushing frequency were considered. Results The prevalence of MetS was 22.2% (n = 48). Study participants with MetS were 2.9 times more likely to have an elevated serum antibody to P. gingivalis (adjusted odds ratio = 2.91, 95% confidence interval = 1.24–6.85) after simultaneous adjustment for other covariates. Conclusion Our findings suggest an independent relationship between MetS and serum antibody levels to P. gingivalis in the Japanese elderly. Additional longitudinal epidemiologic studies with larger, more diversified samples and more complete information are needed to substantiate our findings.

The aim of this study was to analyze the distribution and phenotypic properties of the indigenous streptococci in chimpanzee (Pan troglodytes) oral cavities. Eleven chimpanzees (aged from 9 to 44 years, mean ± SD, 26.9 ± 12.6 years) in the Primate Research Institute of Kyoto University were enrolled in this research and brushing bacterial samples collected from them. Streptococci were isolated from the oral cavities of all chimpanzees. The isolates (n = 46) were identified as thirteen species by 16S rRNA genes analysis. The predominant species was Streptococcus sanguinis of mitis streptococci from five chimpanzees (45%). Mutans streptococci were isolated from six chimpanzees (55%). The predominant species in the mutans streptococci were Streptococcus troglodytae from four chimpanzees (36%), this species having been proposed as a novel species by us, and Streptococcus dentirousetti from three chimpanzees (27%). Streptococcus mutans was isolated from one chimpanzee (9%). However, Streptococcus sobrinus, Streptococcus macacae and Streptococcus downei, which are indigenous to human and monkey (Macaca fasciclaris) oral habitats, were not isolated. Of the mutans streptococci, S. troglodytae, S. dentirousetti, and S. mutans possessed strong adherence activity to glass surface.

Peptide vaccines have two fundamental weak points, namely low antigenicity and MHC-restriction. In our previous study, we proposed the design of vaccine peptide to overcome these weakpoints. The vaccine was constructed in the following order, N-terminal, Arg-Gly-Asp (RGD), T-cell epitope peptide, di-lysine linker (KK) to B-cell epitope peptide. Although the vaccine peptide can basically induce B-cell epitope peptide specific antibodies to the host without immune adjuvants via intraperitoneal, subcutaneous and intranasal administration, some peptide antigens require adjuvants for antibody induction. In this study, we propose a novel protocol to enhance the immunogenicity of the peptide utilizing the host immune response to a conventional toxoid vaccine, which are lymphocyte activities to the T-cell epitope peptide. We selected multiagretope-type T-cell epitopes from diphtheria toxoid, a conventional vaccine antigen, and a part of amyloid-beta peptide (Aβ) as a B-cell epitope. The conventional toxoid vaccine was immunized before the peptide immunization. Using this protocol, we succeeded in the enhancement of the anti-Aβ antibodies induction by intranasal immunization without any immune adjuvants in C57BL/6 and Balb/c mice. Furthermore, the vaccine peptide induced the transformation of peripheral blood lymphocytes collected from healthy volunteers carrying immunities to diphtheria toxoid. These results suggested that our peptide vaccines with the novel protocol would provide an effective method for antibody induction.

Six strains, TKU 25, TKU 28, TKU 30, TKU 31T, TKU 33 and TKU 34, were isolated from the oral cavity of a chimpanzee (Pan troglodytes). Colonies of strains grown on Mitis–Salivarius agar were similar in morphology to that of Streptococcus mutans . The novel strains were Gram-stain-positive, facultatively anaerobic cocci that lacked catalase activity. Analysis of the partial 16S rRNA gene sequences of these isolates showed that the most closely related strain was the type strain of S. mutans (96.4 %). The next closely related strains to the isolates were the type strains of Streptococcus devriesei (94.5 %) and Streptococcus downei (93.9 %). These isolates could be distinguished from S. mutans by inulin fermentation and alkaline phosphatase activity (API ZYM system). The peptidoglycan type of the novel isolates was Glu–Lys–Ala3. Strains were not susceptible to bacitracin. On the basis of phenotypic characterization, partial 16S rRNA gene and two housekeeping gene (groEL and sodA) sequence data, we propose a novel taxon, Streptococcus troglodytae sp. nov.; the type strain is TKU 31T ( = JCM 18038T = DSM 25324T).

Streptococcus troglodytae TKU31 was isolated from the oral cavity of a chimpanzee (Pan troglodytes) and was found to be the most closely related species of the mutans group streptococci to Streptococcus mutans. The complete sequence of TKU31 genome consists of a single circular chromosome that is 2,097,874 base pairs long and has a G + C content of 37.18%. It possesses 2082 coding sequences (CDSs), 65 tRNAs and five rRNA operons (15 rRNAs). Two clustered regularly interspaced short palindromic repeats, six insertion sequences and two predicted prophage elements were identified. The genome of TKU31 harbors some putative virulence associated genes, including gtfB, gtfC and gtfD genes encoding glucosyltransferase and gbpA, gbpB, gbpC and gbpD genes encoding glucan-binding cell wall-anchored protein. The deduced amino acid identity of the rhamnose-glucose polysaccharide F gene (rgpF), which is one of the serotype determinants, is 91% identical with that of S. mutans LJ23 (serotype k) strain. However, two other virulence-associated genes cnm and cbm, which encode the collagen-binding proteins, were not found in the TKU31 genome. The complete genome sequence of S. troglodytae TKU31 has been deposited at DDBJ/European Nucleotide Archive/GenBank under the accession no. AP014612.

This paper critically and selectively surveys the literature on protection for sale and discusses directions for future research in this area. It suggests that the standard approach needs to be augmented to provide more compelling tests of this model. © 2008 Elsevier Inc. All rights reserved.

We propose a new methodology for structural estimation of infinite horizon dynamic discrete choice models. We combine the dynamic programming (DP) solution algorithm with the Bayesian Markov chain Monte Carlo algorithm into a single algorithm that solves the DP problem and estimates the parameters simultaneously. As a result, the computational burden of estimating a dynamic model becomes comparable to that of a static model. Another feature of our algorithm is that even though the number of grid points on the state variable is small per solution-estimation iteration, the number of effective grid points increases with the number of estimation iterations. This is how we help ease the "curse of dimensionality." We simulate and estimate several versions of a simple model of entry and exit to illustrate our methodology. We also prove that under standard conditions, the parameters converge in probability to the true posterior distribution, regardless of the starting values. © 2009 The Econometric Society.

Objectives : The evaluation of Mutans streptococci (MS) is one of the index for caries risk. DentocultTM and CRTTM are commercial kits to detect and evaluate MS, conveniently. However, the evaluation of MS has also been carried out simply using an instruction manual. But the instruction manual is not easy to use for evaluation of MS. The aim of this study was to examine the utility of modified Mitis-Salivalius Bacitracin (MSB) agar medium compared with MSB agar medium and commercial kits, and to establish a convenient kit (mMSB-kit) using modified MSB agar.Methods : The MS in stimulated saliva from 27 subjects were detected by MSB, modified MSB agar medium and commercial kits. Laboratory and clinically isolated strains of MS were similarly evaluated. The ratios of MS in detected bacteria were compared by ELISA.Results : The scores using an mMSB-kit on the basis of modified MSB agar medium were tabulated. Saliva samples showed different levels of MS between culture methods and the commercial kit. Some samples which were full of MS were not detected by the commercial kit. The detection of MS by modified MSB agar medium and mMSB-kit were significantly higher when compared with MSB agar medium, CRTTM, (P< .01) and Dentocult SMTM (PConclusion : The sensitivity for detection of MS is higher for modified MSB agar medium when compared with MSB agar medium. The mMSB-kit can be used simply, and can be an important contributor for the evaluation of MS as a caries risk factor. (Eur J Dent 2007;1:31-39)

The surface properties of three different resin composite materials which influence Streptococcus mutans biofilm formation were evaluated using an artificial mouth system (AMS). Specimens were prepared from Clearfil AP-X, Grandio, and Reactmer Paste, and each material was divided into two groups: (1) surface was ground with 800-grit silicon paper (SiC#800); or (2) surface was polished with up to 1- microm diamond paste (DP1 microm). Biofilms were grown on the surface of each specimen for 20 hours, and then subjected to vortex agitation followed by measurement of retained biofilms. Surfaces with retained biofilms were also inspected by SEM. Significant differences were detected in surface roughness (Ra) between the two polishing conditions for all materials. The quantity of retained biofilm was significantly less (p < 0.05) on Clearfil AP-X DP 1 microm than on Clearfil AP-X SiC#800. With Reactmer Paste, their surfaces registered the lowest amount of retained biofilm--but there were no significant differences between the two polishing conditions. In conclusion, polishing did not render all resin composites equally resistant to biofilm formation.

Three strains TKU9, TKU49 and TKU50(T) , were isolated from the oral cavities of chimpanzees (Pan troglodytes). The isolates were all gram-positive, facultative anaerobic cocci that lacked catalase activity. Analysis of partial 16S rRNA gene sequences showed that the most closely related species was Streptococcus infantis (96.7%). The next most closely related species to the isolates were S. rubneri, S. mitis, S. peroris and S. australis (96.6 to 96.4%). Based on the rpoB and gyrB gene sequences, TKU50(T) was clustered with other member of the mitis group. Enzyme activity and sugar fermentation patterns differentiated this novel bacterium from other members of the mitis group streptococci. The DNA G + C content of strain TKU50(T) was 46.7 mol%, which is the highest reported value for members of the mitis group (40-46 mol%). On the basis of the phenotypic characterization, partial 16S rRNA gene and sequences data for two housekeeping gene (gyrB and rpoB), we propose a novel taxa, S. panodentis for TKU 50(T) (type strain = CM 30579(T) = DSM 29921(T) ), for these newly described isolates.

We propose a new methodology for estimating the demand and cost functions of differentiated products models when demand and cost data are available. The method deals with the endogeneity of prices to demand shocks and the endogeneity of outputs to cost shocks, but does not require instruments for identification. We establish non-parametric identification, consistency and asymptotic normality of our estimator. Using Monte-Carlo experiments, we show our method works well in contexts where instruments are correlated with demand and cost shocks, and where commonly-used instrumental variables estimators are biased and numerically unstable.

We propose a new methodology for estimating the demand and cost functions of differentiated products models when demand and cost data are available. The method deals with the endogeneity of prices to demand shocks and the endogeneity of outputs to cost shocks, by using variation in market size that does not need to be exogenous, and cost data. We establish nonparametric identification, consistency and asymptotic normality of our estimator. Using Monte-Carlo experiments, we show our method works well in contexts where instruments are correlated with demand and cost shocks, and where commonly-used instrumental variables estimators are biased and numerically unstable.

This study aimed to determine whether the long-term use of a fluoride mouthrinse affects the salivary levels of mutans streptococci. Two hundred and fifteen schoolchildren (aged 9–10 years) participated. One hundred and forty-nine of these children had used a fluoride mouthrinse since 5 years of age at nursery school, and the remaining 66 children had not. DFT (decayed and filled teeth) was recorded, and the salivary levels of Streptococcus mutans and Streptococcus sobrinus were measured using mitis salivarius bacitracin agar. The group that had used a fluoride mouthrinse had a significantly lower prevalence of both S. mutans and S. sobrinus (p = 0.038) and a significantly lower DFT score (p < 0.001) than the other group. Using logistic regression analysis including caries experience at baseline as a dependent variable, the odds ratio of carrying S. mutans alone was 8.0 (p = 0.066) and that of carrying both S. mutans and S. sobrinus was 16.5 (p = 0.022) in the group that had not used the fluoride mouthrinse. Children carrying both S. mutans and S. sobrinus had a higher caries incidence in 1 year than the others, with odds ratios of 5.73 (p = 0.067) in the group with a fluoride mouthrinse and 3.47 (p = 0.035) in the group without it. These results show that the long-term use of a fluoride mouthrinse is associated with reduced salivary levels of mutans streptococci and this bacterial reduction may partly contribute to the suppression of dental caries in children using a long-term fluoride mouthrinse.

In this paper, we estimate the effect of workfare policy on crime by exploiting two exogenous welfare policy changes in Denmark. Our results show a strong decline in the crime rate among treated unemployment uninsured men relative to untreated uninsured and unemployment insured men, and part of this decline can be identified as a direct effect of workfare participation. Moreover, we find that criminal activity was also reduced during weekends, when the workfare programs were closed, allowing us to distinguishing the pure program effect from the incapacitation effect. These results imply a strong and potentially lasting crime reducing effect of workfare policy.

Using maximum likelihood techniques and monthly panel data we solve and estimate an explicitly dynamic model of criminal behavior where current criminal activity impacts future labor market outcomes. We show that the threat of future adverse effects in the labor market when arrested acts as a strong deterrent to crime. Moreover, such forward-looking behavior is estimated to be important. Hence, policies that weaken this deterrence will be much less effective in fighting crime. This suggests that prevention is more powerful than redemption since anticipated redemption allows criminals to look forward to negating the consequences of their crimes.

Phosphate ester groups are known to link to some glucosyl residues in starch molecules. We have prepared phosphoryl oligosaccharides (POs) from potato starch hydrolysates. The POs were composed of two fractions, PO-1 and PO-2. Fraction PO-1 was the main fraction, and it was composed of maltotriose, maltotetraose, and maltopentaose to which one phosphoryl group was attached. Fraction PO-2 was predominantly composed of maltopentaose and maltohexaose to which at least two phosphoryl groups were attached. POs had the ability to form a soluble complex with calcium and had an inhibitory effect on the formation of a calcium-phosphate precipitate. Based on the function of the POs, described above, we applied the POs of calcium (POs-Ca) as a food ingredient. POs-Ca was an advantageous food ingredient as a soluble calcium source. In relation to prevention of dental caries, POs cannot be fermented by cariogenic microorganisms or mutans streptococci, and they reduce the fall in plaque pH in vitro. Moreover, POs-Ca effectively enhanced the remineralization of enamel lesions. The aim of this study was to develop the application of POs-Ca for dental health to the enamel remineralization through the chewing of a sugar-free gum.

The use of peptides for various aspects of medical science has been a significant advance. Peptide-based vaccines are promising, but weak immunogenic potency is impeding the clinical application. We have remarkably enhanced the immunogenicity of peptide antigens by addition of motifs that bind to cell attachment proteins, such as arginine-glysine-aspartate (RGD), to the amino acid sequence. The modified peptides induced antigen-specific serum antibodies by intranasal immunization without adjuvants. RGD, an integrin-binding motif was the strongest, among several molecules tested in this experiment, giving an average of 10 times enhancement of antibody titers when incorporated into several peptide antigens. The peptides also acted as an efficient adjuvant following the intranasal immunization with protein antigens. Our data support the feasibility of developing peptide vaccines and peptide adjuvants for intranasal vaccination.

We develop a model of household demand for frequently purchased consumer goods that are branded, storable and subject to stochastic price fluctuations. Our framework accounts for how inventories and expectations of future prices affect current period purchase decisions. We estimate our model using scanner data for the ketchup category. Our results indicate that price expectations and the nature of the price process have important effects on demand elasticities. Long-run cross price elasticities of demand are more than twice as great as short-run cross price elasticities. Temporary price cuts (or “deals”) primarily generate purchase acceleration and category expansion, rather than brand switching.

Water-insoluble glucan (WIG) produced by mutans streptococci, an important cariogenic pathogen, plays an important role in the formation of dental biofilm and adhesion of biofilm to tooth surfaces. Glucanohydrolases, such as mutanase (α-1,3-glucanase) and dextranase (α-1,6-glucanase), are able to hydrolyze WIG. The purposes of this study were to construct bi-functional chimeric glucanase, composed of mutanase and dextranase, and to examine the effects of this chimeric glucanase on the formation and decomposition of biofilm. The mutanase gene from Paenibacillus humicus NA1123 and the dextranase gene from Streptococcus mutans ATCC 25175 were cloned and ligated into a pE-SUMOstar Amp plasmid vector. The resultant his-tagged fusion chimeric glucanase was expressed in Escherichia coli BL21 (DE3) and partially purified. The effects of chimeric glucanase on the formation and decomposition of biofilm formed on a glass surface by Streptococcus sobrinus 6715 glucosyltransferases were then examined. This biofilm was fractionated into firmly adherent, loosely adherent, and non-adherent WIG fractions. Amounts of WIG in each fraction were determined by a phenol-sulfuric acid method, and reducing sugars were quantified by the Somogyi-Nelson method. Chimeric glucanase reduced the formation of the total amount of WIG in a dose-dependent manner, and significant reductions of WIG in the adherent fraction were observed. Moreover, the chimeric glucanase was able to decompose biofilm, being 4.1 times more effective at glucan inhibition of biofilm formation than a mixture of dextranase and mutanase. These results suggest that the chimeric glucanase is useful for prevention of dental biofilm formation.

Titanium and stainless steel wires used for retainers in orthodontic procedures were coated with Ag ions and the effects of the coating on common oral pathogens and their pathogenicity were investigated. Two species of cariogenic and three species of periodontopathic bacteria were assessed. Biofilms of Streptococcus sobrinus and two VSC gases produced by P. gingivalis were also examined. Ag ion-coated wires showed marked antibacterial activities compared with uncoated wires; in most cases, the differences were statistically significant (p

We examine the ability of immigrants to transfer the occupational human capital they acquired prior to immigration. We first augment a model of occupational choice to study the implications of language proficiency on the cross-border transferability of occupational human capital. We then explore the empirical predictions using information about the skill requirements from the O*NET and a unique dataset that includes both the last source country occupation and the first four years of occupations in Canada. We supplement the analysis using Census estimates for the same cohort with source country occupational skill requirements predicted using detailed human capital related information such as field of study. We find that male immigrants to Canada were employed in source country occupations that typically require high levels of cognitive skills, but rely less intently on manual skills. Following immigration, they find initial employment in occupations that require the opposite. Consistent with the hypothesized asymmetric role of language in the transferability of previously acquired cognitive and manual skills, these discrepancies are larger among immigrants with limited language fluency.

In the course of developing a synthetic peptide vaccine for dental caries, we identified a unique 13-mer peptide named PAc(365-377), TYEAALKQYEADL, as a minimum peptide inducing cross-inhibiting antibodies to a cell surface protein antigen (PAc) of Streptococcus mutans. However, the peptide could hardly induce the production of antibody in the absence of adjuvant. Thus using this peptide as a unit peptide, tandem constructs of dimeric unit peptide with or without spacer amino acid residues were synthesized, and their antigenicities were examined in B10.D2 mice. Significant augmentation of antigenicity was obtained in all of the dimeric unit peptides with spacers, especially for lysine spacers. In addition, analysis for cross-reactivity of anti-construct antibodies against a set of double valine-substituted analogues of the unit peptide revealed that the di-lysine spacer might be more effective in inducing the cross-reacting antibodies to rPAc.

Glucosyltransferase (GTF) plays an important role in the development of dental caries. We examined the possible presence of self-inhibitory segments within the enzyme molecule for the purpose of developing anticaries measures through GTF inhibition. Twenty-two synthetic peptides derived from various regions presumably responsible for insoluble-glucan synthesis were studied with respect to their effects on catalytic activity. One of them, which is identical in amino acid sequence to residues 1176-1194, significantly and specifically inhibited both sucrose hydrolysis and glucosyl transfer to glucan by GTF-I. Double-reciprocal analysis revealed that the inhibition is noncompetitive. Scramble peptides, composed of the identical amino acids in randomized sequence, had no effect on GTF-I activity. Furthermore, the peptide is tightly bound to the enzyme once complexed, even in the presence of sodium dodecyl sulfate (SDS). Kinetic analysis using an optical evanescent resonant mirror cuvette system demonstrated that the enzyme-peptide interaction was biphasic. These results indicate that the peptide directly interacts with the enzyme with high affinity and inhibits its activity in a sequence-specific manner. This peptide itself could possibly be an effective agent for prevention of dental caries, although its effectiveness may be improved by further modification.

To assess the prognostic significance of myocardial contractile reserve in patients with idiopathic dilated cardiomyopathy (DCM) without overt heart failure (New York Heart Association functional class I or II), seventy-one patients underwent exercise radionuclide angiography in addition to clinical, radiographic, hemodynamic, and echocardiographic evaluations. Myocardial contractile reserve was assessed as left ventricular ejection fraction (LVEF) during peak exercise minus LVEF at rest (delta LVEF). During an average of 49 months, 18 patients died of the disease. Cox's proportional-hazards regression analysis showed that the delta LVEF was the most powerful and independent discriminator for survival (p = 0.0002). Ejection time (p = 0.0029) and cardiothoracic ratio (p = 0.017) were the second and third most predictive variables, respectively. Evaluation of the delta LVEF, which reflects residual myocardial contractile reserve, can provide important information about the prognosis of patients with DCM and mild symptoms.

We describe the novel karyotype of a 33-year-old woman with severe mental retardation and multiple cardiac anomalies, including patent ductus arteriosus, a ventricular septal defect, pulmonary atresia, and an overriding aorta. Her karyotype was 46, XX, add(17)(p13). The short arm of chromosome 17 was slightly elongated owing to the deletion of the distal portion of that chromosome and the addition of extra material from another chromosome. Miller-Dieker syndrome is characterized by a patent ductus arteriosus, lissencephaly, and the deletion of chromosome 17p13.3; however, as the patient's brain surface appeared normal on computed tomography, Miller-Dieker syndrome was excluded. The breakpoint in her chromosome 17 was probably located distal to band 17p13.3. In fact, fluorescence in situ hybridization analysis demonstrated that band 17p13.3 was intact. To date, genes distal to 17p13.3 have not been implicated in cardiac anomalies. This patient probably carries a novel deletion on the short arm of chromosome 17.

This paper proposes a new test of the Protection for Sale (PFS) model by Grossman and Helpman (1994). Unlike existing methods in the literature, our approach does not require any data on political organizations. We formally show that the PFS model predicts that the quantile regression of the protection measure on the inverse import penetration ratio divided by the import demand elasticity, should yield a positive coefficient for quantiles close to one. We test this prediction using the data from Gawande and Bandyopadhyay (2000). The results do not provide any evidence favoring the PFS model.

The aim of this study was to analyze the distribution and phenotypic properties of the indigenous streptococci in chimpanzee (Pan troglodytes) oral cavities. Eleven chimpanzees (aged from 9 to 44 years, mean ± SD, 26.9 ± 12.6 years) in the Primate Research Institute of Kyoto University were enrolled in this research and brushing bacterial samples collected from them. Streptococci were isolated from the oral cavities of all chimpanzees. The isolates (n = 46) were identified as thirteen species by 16S rRNA genes analysis. The predominant species was Streptococcus sanguinis of mitis streptococci from five chimpanzees (45%). Mutans streptococci were isolated from six chimpanzees (55%). The predominant species in the mutans streptococci were Streptococcus troglodytae from four chimpanzees (36%), this species having been proposed as a novel species by us, and Streptococcus dentirousetti from three chimpanzees (27%). Streptococcus mutans was isolated from one chimpanzee (9%). However, Streptococcus sobrinus, Streptococcus macacae and Streptococcus downei, which are indigenous to human and monkey (Macaca fasciclaris) oral habitats, were not isolated. Of the mutans streptococci, S. troglodytae, S. dentirousetti, and S. mutans possessed strong adherence activity to glass surface.