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Enterohemorrhagic Escherichia coli O157 (O157) strains can be subdivided into clades based on their single-nucleotide polymorphisms, but such analysis using conventional methods requires intense effort by laboratories. Although multi-locus variable-number tandem repeat analysis (MLVA), which can be performed with low laboratory burden, has been used as a molecular epidemiological tool, it has not been evaluated whether MLVA can be used the clade subdivision of O157 strains like it can for that of other pathogenic bacteria. This study aimed to establish a method for subdividing O157 strains into clades using MLVA data. The standardized index of association, ISA, for O157 strains isolated in Chiba prefecture, Japan (Chiba isolates) revealed the presence of unique tandem repeat patterns in each major clade (clades 2, 3, 7, 8, and 12). A likelihood database of tandem repeats for these clades was then constructed using the Chiba isolates, and a formula for maximum a posteriori (MAP) estimation was constructed. The ratio of the number of O157 strains putatively subdivided into a clade by MAP estimation from MLVA data relative to the number of O157 strains subdivided using single-nucleotide polymorphism analysis (designated as the concordance ratio [CR]) was calculated using the Chiba isolates and O157 strains isolated in Yamagata prefecture (Yamagata isolates). The CRs for the major Chiba and Yamagata isolate clades, other than clade 2, were 89%–100%. Although the CR for clade 2 Chiba isolates was >95%, that of the Yamagata isolates was only 78.9%. However, these clade 2 CRs were not significantly different from one another, indicating that clade 2 strains can be subdivided correctly by MAP estimation. In conclusion, this study expands the utility of MLVA, previously applied predominantly for molecular epidemiological analysis, into a low-laboratory-burden tool for subdividing O157 strains into phylogenetic groups. [ABSTRACT FROM AUTHOR]

Simultaneous measurements of high-speed high-resolution particle image velocimetry near the piston top with spatial resolution of 152 × 76 μ m at 24 kHz and a micro-electro-mechanical-systems (MEMS) heat flux sensor on the piston surface was conducted in a motored optical gasoline engine with enhanced tumble flow for 2000 rpm. Characteristics of mean velocity profiles are discussed based on fitting to the turbulent and laminar boundary layers with conditioning by momentum. It has been found that the velocity profile of high momentum tends to be close to that of turbulent boundary layer, while its probability is not large. Cross correlation between maximum heat flux in each cycle and velocity in the piston-surface normal direction shows that heat flux is 3 CAD behind the velocity, which corresponds to about 0.25 ms. Also it is found that the correlation coefficient shows higher value at 0.50 mm from the piston wall rather than that at 0.27 and 0.12 mm with the delay of 3 CADs for heat flux. Furthermore, cross correlation coefficient of fluctuating components of heat flux and velocity shows also the similar tendency. [ABSTRACT FROM AUTHOR]

In Japan's Kanto region, the number of Salmonella enterica serovar Chester infections increased temporarily between 2014 and 2016. Concurrently with this temporal increase in the Kanto region, S. Chester isolates belonging to one clonal group were causing repetitive outbreaks in Europe. A recent study reported that the European outbreaks were associated with travelers who had been exposed to contaminated food in Morocco, possibly seafood. Because Japan imports a large amount of seafood from Morocco, we aimed to establish whether the temporal increase in S. Chester infections in the Kanto region was associated with imported Moroccan seafood. Short sequence reads from the whole-genome sequencing of 47 S. Chester isolates from people in the Kanto region (2014–2016), and the additional genome sequences from 58 isolates from the European outbreaks, were analyzed. The reads were compared with the complete genome sequence from a S. Chester reference strain, and 347 single nucleotide polymorphisms (SNPs) were identified. These SNPs were used in this study. Cluster and Bayesian cluster analyses showed that the Japanese and European isolates fell into two different clusters. Therefore, Φ PT and I A S values were calculated to evaluate genetic differences between these clusters. The results revealed that the Japanese and European isolates were genetically distinct populations. Our root-to-tip analysis showed that the Japanese isolates originating from one clone had accumulated mutations, suggesting that an emergence of this organism occurred. A minimum spanning tree analysis demonstrated no correlation between genetic and geographical distances in the Japanese isolates, suggesting that the emergence of the serovar in the Kanto region did not involve person-to-person contact; rather, it occurred through food consumption. The d N / d S ratio indicated that the Japanese strain has evolved under positive selection pressure. Generally, a population of bacterial clones in a reservoir faces negative selection pressure. Therefore, the Japanese strain must have existed outside of any reservoir during its emergence. In conclusion, S. Chester isolates originating from one clone probably emerged in the Kanto region via the consumption of contaminated foods other than imported Moroccan seafood. The emerging strain may have not established a reservoir for survival in the food supply chain resulting in its disappearance after 2017. [ABSTRACT FROM AUTHOR]

This study investigated the genetic and pathogenic variation of the subgroups of clade 2 strains of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157. A total of 111 strains of STEC O157 isolated in Shimane prefecture, Japan, were classified in clade 2 (n = 39), clade 3 (n = 16), clade 4/5 (n = 3), clade 7 (n = 14), clade 8 (n = 17), and clade 12 (n = 22) by single-nucleotide polymorphism analysis and lineage-specific polymorphism assay-6. These results showed a distinct difference from our previous study in which clade 3 strains were the most prevalent strains in three other prefectures in Japan, indicating that the clade distribution of O157 strains was different in different geographic areas in Japan. Phylogenetic analysis using insertion sequence (IS) 629 distribution data showed that clade 2 strains formed two clusters, designated 2a and 2b. Stx2 production by cluster 2b strains was significantly higher than by cluster 2a strains (P < 0.01). In addition, population genetic analysis of the clade 2 strains showed significant linkage disequilibrium in the IS629 distribution of the strains in clusters 2a and 2b (P < 0.05). The ΦPT values calculated using the IS629 distribution data indicated that strains in clusters 2a and 2b were genetically different (P < 0.001). Cluster 2b strains are a highly pathogenic phylogenetic group and their geographic spread may be a serious public health concern. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli O157 (O157) strains can be classified into clades (one of several phylogenetic groups) by single nucleotide polymorphisms (SNPs): these are clade 1, clade 2, clade 3, descendant and ancestral clades 4/5, clade 6, clade 7, clade 8, clade 9, and clade 12. Some recent studies showed that some O157 strains in clade 8 produced a larger amount of Shiga toxin (Stx) 2 than other strains. In this study, 1121 epidemiologically unlinked strains of O157 isolated in Chiba Prefecture, Japan were classified into clades during 1996–2014. Clade 8 strains were further classified into subclade 8a (67 strains) and subclade 8b (48 strains) using SNP analysis. In the absence of mitomycin C (MMC), subclade 8a strains in this study produced significantly greater amounts of Stx2 than subclade 8b strains. However, in the presence of MMC, the levels of Stx2 production in subclade 8b strains were significantly greater than subclade 8a strains. On the other hand, a recent study reported that the Stx2 production level in O157 strains was determined mainly by the subtypes of Stx2a phage (ϕStx2_α, β, γ, δ, ε, and ζ). Using O157 strains in this study, the Stx2a phages were classified into these subtypes. In this study, all strains of subclades 8a and 8b carried ϕStx2a_γ and ϕStx2a_δ, respectively. Some strains in clade 6 also carried ϕStx2a_δ. In the presence of MMC, subclade 8b strains produced significantly greater amounts of Stx2 than clade 6 strains carrying ϕStx2_δ. In this study, we propose that Stx2 production in subclade 8b strains in the presence of MMC might be enhanced due to genetic factors other than ϕStx2_δ. [ABSTRACT FROM AUTHOR]

Nine Shiga toxin-producing Escherichia coli O157:H7/H- (O157) strains were serially cultured three times on LB agar plates. After each sub-culture, five colonies were picked for DNA isolation and whole genome sequence (WGS) analysis. After exclusion of possible recombination-related SNPs, 11, 9, and 34 single-nucleotide polymorphisms (SNPs) were detected in genes in the backbone, O-island, and mobile elements gene categories. This suggested that those SNPs due to cultivation could influence the threshold value set for molecular epidemiological studies of O157. Significant differences were observed by the Kruskal-Wallis test (P < 0.01) when the number of the SNPs in a strain was compared to that in other strains. This indicated that a specific number of strains could be used for setting the threshold value in molecular epidemiological studies. Due to cultivation, the SNPs were also detected in genes in a few core genome or core gene sets, suggesting that those SNPs could affect studies of phylogeny as well as molecular epidemiology. To improve the accuracy of phylogenetic and molecular epidemiological studies, genes in which the SNPs have arisen due to cultivation should be excluded from WGS data. [ABSTRACT FROM AUTHOR]

The sporulation inhibitory gene spi in the pock-forming conjugative plasmid pSA1.1 of Streptomyces azureus was introduced into cells via a high or low copy number vector to examine the effect of gene dosage on the growth of Streptomyces lividans TK24 as a host. In transformants carrying a high spi copy number, nutrient mycelial growth was inhibited, as was morphological differentiation from substrate mycelium to aerial mycelium on solid media. The degree of inhibition depended on the spi gene dosage, but the presence of pSA1.1 imp genes, which encode negative repressor proteins for spi, relieved the inhibition. Confocal images of Spi tagged with enhanced green fluorescent protein in cells on solid media revealed that spi expression was initiated at the time of elongation of substrate mycelium, that its expression increased dramatically at septation in aerial hyphae, and that the expression was maximal during prespore formation. Expression of spi covered the whole of the hyphae, and the level of expression at the tip of the hyphae during prespore formation was about sixfold greater than during substrate mycelial growth and threefold greater than during aerial mycelial growth. Thus, localized expression of spi at particular times may inhibit sporulation until triggering imp expression to repress its inhibitory effects. [ABSTRACT FROM AUTHOR]

To compare the efficacy and safety of silodosin and tamsulosin in patients with lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) by a randomized crossover method. BPH patients with the complaint of LUTS were included in this study, and were randomly divided into two groups: a silodosin-preceding group (4 weeks of twice-daily administration of silodosin at 4 mg, followed by 4 weeks of once-daily administration of tamsulosin at 0.2 mg) or a tamsulosin-preceding group (4 weeks' administration of tamsulosin, followed by 4 weeks' administration of silodosin). No drug withdrawal period was provided when switching the drug. In the first treatment period, both drugs significantly improved the International Prostate Symptom Score total score, but the improvement by silodosin was significantly superior to that by tamsulosin. After crossover treatment, significant improvement was observed only with silodosin treatment. Moreover, intergroup comparison of changes revealed that silodosin showed significant improvement of straining and nocturia with first and crossover treatments, respectively, compared with tamsulosin. Silodosin also significantly improved quality of life (QOL) score in both treatment periods, while tamsulosin significantly improved QOL score only in the first treatment period. The most frequent adverse drug reaction was ejaculatory disorder with silodosin; however, the incidence of dizziness with silodosin was similar to that with tamsulosin. In BPH/LUTS patients, silodosin exhibits excellent efficacy in improving subjective symptoms in both initial and crossover treatment, and it appears to improve the QOL of patients. [ABSTRACT FROM AUTHOR]

A total of 132 Streptococcus pneumoniae isolates collected between 2005 and 2006 in Japan were examined for susceptibility to telithromycin (TEL) and macrolide. The overall resistance to macrolide was 80%. Among the isolates, 128 strains had low-level TEL susceptibility (minimal inhibitory concentrations [MICs] 0.03–1 μg mL−1), suggesting that pneumococci with reduced susceptibility to TEL have appeared without prior exposure to the drug, although none of the isolates were assigned as TEL-resistant (breakpoint, ≥4 μg mL−1). Eight of these isolates (MIC 0.5–1 μg mL−1) were analyzed for macrolide resistance determinants and genetic relatedness. They all carried mefE- mel, which encodes the macrolide efflux genetic assembly, and three also harbored ermB, which encodes rRNA methylase. Allele replacement mutagenesis of the corresponding genes in the clinical isolates revealed that reduced TEL susceptibility (MIC 1 μg mL−1) in S. pneumoniae may be caused by acquisition of the mefE- mel element only and additionally conferred by the ermB determinant. [ABSTRACT FROM AUTHOR]

A novel gene amplification method, loop-mediated isothermal amplification (LAMP), has been recently developed as a rapid, specific diagnostic method for various infectious diseases. We have investigated whether LAMP can be used to detect small numbers of enteroaggregative Escherichia coli (EAEC) cells contaminated in food samples. Primers for LAMP reaction were designed with EAEC aggR gene sequences (available in GenBank). LAMP specificity with these primer', was the same as that of PCR in a study of 37 EAEC and 42 non-EAEC bacterial strains. The sensitivity of the LAMP method was belier than that of PCR in a study of serially diluted EAEC cells. The LAMP method was significantly more effective than was PCR in detecting EAEC-contaminated food samples (Fisher's exact test, P < 0.05). Therefore, the LAMP method described here should be useful for detecting small numbers of EAEC cells in food samples. [ABSTRACT FROM AUTHOR]

Ninety-five enterohemorrhagic Escherichia coli serovar O157 strains, including 30 strains isolated from 13 intrafamily outbreaks and 14 strains isolated from 3 mass outbreaks, were studied by pulsed-field gel electrophoresis (PFGE) and variable number of tandem repeats (VNTR) typing, and the resulting data were subjected to cluster analysis. Cluster analysis of the VNTR typing data revealed that 57 (60.0%) of 95 strains, including all epidemiologically linked strains, formed clusters with at least 95% similarity. Cluster analysis of the PFGE patterns revealed that 67 (70.5%) of 95 strains, including all but 1 of the epidemiologically linked strains, formed clusters with 90% similarity. The number of epidemiologically unlinked strains forming clusters was significantly less by VNTR cluster analysis than by PFGE cluster analysis. The congruence value between PFGE and VNTR cluster analysis was low and did not show an obvious correlation. With two-step cluster analysis, the number of clustered epidemiologically unlinked strains by PFGE cluster analysis that were divided by subsequent VNTR cluster analysis was significantly higher than the number by VNTR cluster analysis that were divided by subsequent PFGE cluster analysis. These results indicate that VNTR cluster analysis is more efficient than PFGE cluster analysis as an epidemiological tool to trace the transmission of enterohemorrhagic E. coli O157. [ABSTRACT FROM AUTHOR]

This paper proposes a control system which improves OPU (Optical Pick Up) control performance in an optical disk system. This system can be realized by adding a correction pulse control block which is based on a position error signal onto a conventional position control loop composed of the PID control rule. Using this function, the position error resulting from a physical distortion and acceleration disturbance to the disk can be decreased sharply. Furthermore, this system can decrease the deviation caused by the shock disturbance which cannot be controlled by the PID control rule. In addition, it becomes possible to decrease the overshoot in the impulse response sharply, and realize stable capture of a target position. Since this system can be created with a simple algorithm, it is possible to use it in a wide range of applications. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(2): 53–67, 2007; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/eej.20570 [ABSTRACT FROM AUTHOR]

Entomopathogens and other econutritional fungi belonging to Clavicipitaceae were phylogenetically analyzed on the basis of the 18S rRNA gene and mating-type genes ( MAT1-1-1 and MAT1-2-1). The phylogenies of the mating-type genes yielded better resolutions than that of 18S rRNA gene. Entomopathogens ( Cordyceps bassiana, Cordyceps brongniartii, Cordyceps militaris, Cordyceps sinclairii, Cordyceps takaomontana, Isaria cateniannulata, Isaria farinosa, Isaria fumosorosea, Isaria javanica, Lecanicillium muscarium and Torrubiella flava) were considered as a phylogenetically defined group, and were closely related to mycopathogens ( Lecanicillium psalliotae and Verticillium fungicola). They located at more descendant positions in the mating-type trees than other fungi, and lacked the mating-type gene MAT1-1-3. The deletion of MAT1-1-3 was supposed to have occurred once in Clavicipitaceae, and a good indication for the evolution of Clavicipitaceae. Other entomopathogens ( Cordyceps cylindrica, Cordyceps subsessilis, Metarhizium anisopliae and Nomuraea rileyi) and pathogens of plants, nematodes and slime molds, were relatively related to each other, and possessed MAT1-1-3, but were supposed to be heterogeneous. Root-associated fungi did not form any clade with other species. [ABSTRACT FROM AUTHOR]

The entomopathogenic fungus Cordyceps militaris belongs to vegetable wasps and plant worms and is used as herbal medicine, but β-1,3-glucan biosynthesis has been poorly studied in C. militaris. The fungal FKS1 gene encodes an integral membrane protein that is the catalytic subunit of β-1,3-glucan synthase. Here, we isolated cDNA clones encoding a full-length open reading frame of C. militaris FKS1. Cordyceps militaris Fks1 protein is a 1981 amino acid protein that shows significant similarity with other fungal Fks proteins. This study is the first report of molecular cloning of the β-1,3-glucan synthase catalytic subunit gene from vegetable wasps and plant worms. [ABSTRACT FROM AUTHOR]

Abstract: Perithecium formation of an entomopathogenic fungus Cordyceps takaomontana was promoted by treating the mycelia with cell wall-degrading enzymes and PEG 4000. Perithecia were formed in the mixed culture of both mating-type strains MAT1 and MAT2, and not in the culture of MAT1 or MAT2 alone. The MAT1 strains did not possess a mating-type gene MAT1-1-3, but could produce perithecia. These results strongly suggested that C. takaomontana is heterothallic, and does not need MAT1-1-3 for the perithecium formation. MAT1-1-3 was also not found in another entomopathogenic fungus Cordyceps militaris. On the other hand, phytopathogenic fungi Balansia sp., Claviceps purpurea and Epichloë typhina possessed MAT1-1-3. The structures of mating-type locus MAT1-1 of these phytopathogenic fungi in the family Clavicipitaceae were similar to that of a phytopathogenic fungus Gibberella fujikuroi in the family Nectriaceae, which is closely related to Clavicipitaceae. These results suggested that phytopathogen might be more ancestral group than entomopathogen in Clavicipitaceae, and that MAT1-1-3 might be lost in the course of the host shift from plants to insects. [Copyright &y& Elsevier]

This study developed a PCR-based mating-type assay for Clavicipitaceae. PCR primer sets for the mating-type genes MAT1-1-1 and MAT1-2-1 were designed based on the amino acid sequences of the conserved alpha and HMG boxes, respectively. The PCR-based mating-type assay could be applied for various clavicipitaceous genera (Balansia, Claviceps, Cordyceps and Epichloë). Most of the clavicipitaceous fungi possessed either MAT1-1-1 or MAT1-2-1, and were supposed to be heterothallic. Although the PCR products obtained by the mating-type assay were short, the phylogenetic trees of the mating-type genes gave better resolutions than that of 18S rDNA and agreed well to their econutritional modes. [Copyright &y& Elsevier]

Contractile motility of the gallbladder was compared using a real-time ultrasonography in 13 patients with gastric ulcer and 31 patients with gastric cancer who had undergone either subtotal or total gastrectomy within 1 month previously. Contractile motility of the gallbladder after oral administration of dried egg yolk (Daiyan, Maruishi, Osaka), which was slightly hut not significantly reduced in patients with gastric ulcer, was remarkedly impaired in patients with gastric cancer who had either subtotal or total gastrectomy including radical lymph node dissection. Especially, maximum contractile rate after Daiyan in Billroth II patients was significantly reduced than that of Billroth 1 patients. Intramuscular injection of naloxone (0.4 mg), which had no effects on contractions after Daiyan in healthy subjects, significantly improved the hypomotility in response to Daiyan in these gastric cancer patients. It was suggested, therefore, that the possible roles of various anatomical and mechanical changes resulting from gastrectomy including vagotomy and sympathectomy, and in particular exclusion of duodenum from digestive circuits and relative or absolute excess of endogenous opioids, were involved in the control of the gallbladder motility within 1 month after gastrectomy including lymphadenectomy. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli serovar O157 (O157) strains with highly similar pulsed-field gel electrophoresis (PFGE) patterns were isolated in Japan during 2007 and 2008. Several genetic features related to O157 evolution were investigated to indicate whether homoplasy might have contributed to the highly similar PFGE patterns in these strains. The O157 strains were classified in lineage I/II, as defined by a lineage-specific polymorphism assay-6 with an atypical allele in Z5935 (code: 231111). Analysis of the insertion sites of stx2 phage in these strains showed that the sites were "occupied" in yehV and "intact" in wrbA, indicating that the strains were derived from "Cluster 1" of "Subgroup C." When a specific single-nucleotide polymorphism in ECs2357 in clade 8 strains was investigated, all of the strains in the present study were confirmed to be clade 8 strains. These results indicated that the O157 strains in this study had common genetic features, suggesting that the highly similar PFGE patterns of these strains were not due to homoplasy. Because no common source of these strains could be identified in 2007 to 2008 in Japan, these strains may have emerged from a unique O157 clade 8 clone and then spread by dissemination in Japan. [ABSTRACT FROM AUTHOR]

Describes a method for measuring the respiratory uptake of carbon monoxide in unanesthetized rats. Application of the method to ozone exposed rats; Viability of the method; Decrease in carbon monoxide uptake after exposure of rats to ozone; Changes in the lung weight.