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Abstract: We evaluate response of Mid‐Niigata during the preseismic, coseismic, and postseismic periods of the 2011 Mw9.0 Tohoku‐oki earthquake by analyzing strain distributions based on a dense Global Positioning System network. Decomposition of the coseismic E‐W strain according to its wavelength shows localized elastic extension, while persistent localized contraction in the short‐wavelength component within a narrow zone of 40‐ to 60‐km width is significant before and after the event, implying the persistence of an inelastic process. Differences in the amplitude and horizontal location of the localized deformation suggest that elastic heterogeneities of the crust, acting in different sense before and after the earthquake, affect the deformation in Mid‐Niigata as well. We model localized deformation in the preseismic and postseismic period considering an aseismic fault slip and a weak elastic zone as deformation sources. Our kinematic models suggest vertical decoupling between the weak elastic layer and the basement rock, implying that the preseismic and postseismic strain rate patterns represent direct effects of the shallow portion of the crust in Mid‐Niigata. Although model parameters are not well constrained, we find that faults cutting the lower crust and a part of the upper crust, and an anomalously weak zone of a 40‐ to 60‐km width located above the fault explain the data. Our simple model shows that both inelastic and elastic sources are essential in the deformation mechanism of the Mid‐Niigata area in northern Niigata‐Kobe Tectonic Zone. [ABSTRACT FROM AUTHOR]

In addition to standard postmarketing drug safety monitoring, Section 915 of the Food and Drug Administration Amendments Act of 2007 (FDAAA) requires the US Food and Drug Administration (FDA) to conduct a summary analysis of adverse event reports to identify risks of a drug or biologic product 18 months after product approval, or after 10,000 patients have used the product, whichever is later. We assessed the extent to which these analyses identified new safety signals and resultant safety-related label changes. Among 458 newly approved products, 300 were the subjects of a scheduled analysis; a new safety signal that resulted in a safety-related label change was found for 11 of these products. Less than 2% of 713 safety-related label changes were based on the scheduled analyses. Our study suggests that the safety summary analyses provide only marginal value over other pharmacovigilance activities. [ABSTRACT FROM AUTHOR]

Aims: To clarify the distribution and significance of the oesophageal and gastric cardiac mucosae at the oesophago–gastric junction (EGJ). Methods and results: Oesophagectomy specimens from 131 consecutive patients with middle and upper thoracic oesophageal cancer were examined. The surgically resected specimens including the EGJ were cut into 5 mm thick serial sections and examined histopathologically for the length of the oesophageal and gastric cardiac mucosae and the incidence of columnar epithelial islands (CEIs). We also determined the presence of short-segment Barrett's oesophagus (SSBE) and goblet cell metaplasia in SSBE. Oesophageal cardiac mucosa was found in 125 cases (95%) and gastric cardiac mucosa was found in all cases. The mean length of the oesophageal and gastric cardiac mucosa was 4 mm (range 1–26 mm) and 13 mm (range 2–64 mm), respectively. CEIs were found in 75 cases (57%). SSBE was found in 70 cases (53%), among which goblet cell metaplasia was found in 28 cases (21%). No long-segment Barrett's oesophagus was found. The mean length of oesophageal cardiac mucosa (6 mm) and gastric cardiac mucosa (17 mm) in SSBE was significantly greater than that (3 mm and 8 mm, respectively) in non-SSBE cases ( P < 0.0001 and P < 0.0001). The incidence (69%) of CEIs in SSBE was significantly higher than that (44%) in non-SSBE cases ( P = 0.005). Conclusions: Oesophageal and gastric cardiac mucosae were found frequently. Oesophageal cardiac glands and CEIs might play an important role in the development of SSBE. [ABSTRACT FROM AUTHOR]

Aims: Adamantinomatous craniopharyngioma (ACP) resembles histologically some odontogenic tumours, such as ameloblastoma and calcifying odontogenic cyst. However, there has been no evidence that ACP differentiates also functionally as odontogenic epithelium. The aim of this study was to gain evidence of odontogenic epithelial differentiation in ACP by means of immunohistochemistry. Among normal human tissues, enamel proteins are expressed exclusively in teeth, and lymphoid enhancer factor 1 (LEF1), in co-operation with β-catenin, play an important role in tooth development. The expression of these proteins is therefore indicative of odontogenic epithelial differentiation. Methods and results: The expression of enamel proteins and LEF1 was examined in 10 adamantinomatous and six papillary craniopharyngiomas. All the ACPs showed a variable degree of enamel protein expression, including amelogenin, enamelin and enamelysin, mainly in ghost cells. LEF1 was also heterogeneously expressed in ACPs; remarkably, its expression pattern was identical to that of nuclear β-catenin accumulation. In contrast, none of the papillary craniopharyngiomas expressed enamel proteins or LEP1. Conclusions: These results suggest that ACP consistently shows odontogenic epithelial differentiation. Since ACPs harbour β-catenin mutation, the inappropriate activation of β-catenin/LEF1 complex-dependent transcription may play a critical role in ACP tumorigenesis. [ABSTRACT FROM AUTHOR]

Quantitative analysis, with identification of periodontopathic bacteria, is important for the diagnosis, therapeutic evaluation and risk assessment of periodontal disease. We developed a highly sensitive and specific method using real-time polymerase chain reaction (PCR) to detect and quantify six periodontal bacteria: Porphyromonas gin givalis, Tannerella forsythia, Actinobacillus actinomycetemcomitans, Treponema denticola, Prevotella intermedia, and Prevotella nigrescens. Species-specific TaqMan probe/primer sets were designed according to 16S ribosomal RNA gene sequences. Plaque and tongue debris specimens were collected from 10 patients with advanced periodontitis and 10 periodontal healthy individuals and analyzed. All species, except for P. nigrescens, were detected in samples from diseased sites in significantly greater numbers than in those from healthy sites, whereas greater numbers of P. nigrescens were found in the controls. These results suggest that the present real-time PCR method with the designed probe/primer sets enabled sensitive detection of the six periodontal bacteria, and may also assist future microbial studies of periodontal diseases. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about gastrointestinal stromal tumours.

Background: Helicobacter pylori infection causes gastric neoplasia via development of chronic atrophic gastritis and intestinal metaplasia. The effect of H. pylori eradication on pre-existing gastric neoplasias is still controversial. The aim of this study was to use long-term observation to clarify morphologic and histologic changes in gastric adenomas following H. pylori eradication., Materials and Methods: Twenty-seven patients with gastric adenomas (revised Vienna classification category 3 or 4.1) who underwent successful H. pylori eradication between April 1996 and December 1997 were followed up at regular intervals with endoscopic and histologic examination. The association between macroscopic and histologic regressions of the lesions and the following patient and lesion characteristics was assessed with univariate analysis: follow-up period, age, sex, serum pepsinogen level, lesion size, lesion location, and histologic gastritis., Results: The mean follow-up period was 91.9 months (range 44-181 months). Twelve lesions (44.4%) showed macroscopic regression, of which 7 (25.9% of the total) also showed histologic regression, with the mean duration from H. pylori eradication to complete macroscopic and histologic regression being 19.9 months. The other 15 lesions (55.6%) remained stable macroscopically and histologically, of which 6 (22.2% of the total) progressed to malignancy during the follow-up period. Univariate analysis revealed that female sex (p = .005), smaller lesion size (p = .025), higher baseline serum pepsinogen II level (p = .041), and absence of intestinal metaplasia in the greater curvature of the corpus (p = .026) were significantly associated with complete regression., Conclusions: Helicobacter pylori eradication may induce regression in some gastric adenomas., (© 2015 John Wiley & Sons Ltd.)

DNA-dependent RNA polymerase (RNAP) synthesizes RNA complementary to the template DNA. During transcript elongation, RNAP often undergoes backward translocation ('backtracking') by dissociating the 3' end of the nascent RNA transcript from the template DNA. While the backtracked state of RNAP is inactive in RNA elongation, it actively hydrolyses the RNA 3' end to regenerate the active elongation complex. To study the structural basis of the backtracked state and its cleavage activity, two backtracked RNAP complexes were reconstituted by assembling Thermus thermophilus RNAP with designed nucleic acid scaffolds. The reconstituted backtracked complexes were active in the transcript-cleavage reaction. These complexes were crystallized and X-ray diffraction data sets were obtained at resolutions of 3.4 and 3.7 Å.

Selenocysteine (Sec), the 21st amino acid, is synthesized on its specific tRNA (tRNA(Sec)) via a multi-step process. In bacteria, tRNA(Sec) is ligated first with serine by seryl-tRNA synthetase, which is followed by Ser-to-Sec conversion by Sec synthase (SelA). To elucidate its structure and catalytic mechanism, Aquifex aeolicus SelA was crystallized. Although wild-type SelA crystals diffracted X-rays poorly (to up to 8 Å resolution), the resolution was improved by introducing a quadruple point mutation targeting the loop regions and by methylating the lysine residues, which yielded 3.9 Å resolution diffraction data from a full-length SelA crystal. Truncation of the N-terminal region (ΔN) also improved the resolution. A 3.3 Å resolution data set for phase determination was obtained from a crystal of selenomethionine-substituted Lys-methylated SelA-ΔN.

RNA polymerase (RNAP) elongates RNA by iterative nucleotide-addition cycles (NAC). A specific structural state (or states) of RNAP may be the target of transcription elongation factors. Gfh1, a Thermus thermophilus Gre-family protein, inhibits NAC. To elucidate which RNAP structural state Gfh1 associates with, the T. thermophilus RNAP elongation complex (EC) was cocrystallized with Gfh1. Of the 70 DNA/RNA scaffolds tested, two (for EC1 and EC2) were successfully crystallized. In the presence of Gfh1, EC1 and EC2 yielded crystals belonging to space group P2(1) with similar unit-cell parameters (crystals 1 and 2, respectively). X-ray diffraction data sets were obtained at 3.6 and 3.8 A resolution, respectively.

The gene encoding LysX, an essential component of the lysine-biosynthesis pathway in Thermus thermophilus (molecular weight approximately equal 31,000 Da), was cloned and expressed and the purified protein was crystallized by the hanging-drop vapour-diffusion technique in two different space groups, C2 (unit-cell parameters a = 124.7, b = 51.4, c = 103.6 A, beta = 122.8 degrees ) and R3 (a = b = 122.6, c = 97.6 A). Crystals improved by macroseeding diffracted to beyond 2.3 and 3 A resolution for the C2 and R3 crystal forms, respectively. Complete diffraction data sets were collected for the C2 and R3 crystal forms at 2.5 and 3.1 A resolution, respectively. Crystals of selenomethionine-containing LysX protein were obtained by cross-microseeding, using the native microcrystals as a seed. Structure determination is now in progress.

Chitosan posttreatment has been shown to be effective in prevention of calcification of the glutaraldehyde treated bovine pericardium when implanted subdermally in rats for 12 weeks. The efficacy of chitosan posttreatment in complete calcium mitigation of the glutaraldehyde treated porcine aortic valves implanted in the right side of the heart in dogs was well-documented in our previous study. In this study, an attempt has been made to evaluate the merit of the chitosan posttreatment in prevention of calcification of the glutaraldehyde (GA) treated porcine aortic valved conduits in the systemic circulation in dogs for a period of 5 months. Eleven mongrel dogs underwent left thoracotomy. Porcine aortic valved conduits treated with 0.625% GA (n = 5) and GA-chitosan (n = 6) were implanted in the descending thoracic aortas of the dogs for 5 months. Gross histological observations showed no calcification in either the 0.625% GA treated or in the GA-chitosan treated valved conduits at 5 months. This was confirmed by results of quantitative analyses for calcium in each explant. There was no significant difference in calcium content between the GA only (Ca, 0.43 +/- 0.26 mg/g) and GA-chitosan treated (Ca, 0.51 +/- 0.19 mg/g; p = 0.5959) valved conduits. This study suggests that the dog is not a suitable model for evaluating the efficacy of a calcium mitigating agent in bioprostheses implanted in systemic circulation.

During the three-year period from 1984 to 1987, 506 acute gastroenteritis outbreaks involving 14,383 patients were reported to the Bureau of Public Health, Tokyo Metropolitan Government. Eighty (4,324 patients) of 150 outbreaks (4,860 patients) from which etiologic agents were not identified were subjected to virological investigation. Spherical particles of 28-32 nm in diameter with capsomere-like structures on the surface were detected in patients' stool specimens. Buoyant density of the particles appeared to be 1.36 to 1.40 g/ml in CsCl. Seroconversion to the particles was observed in patients by immune electron microscopy. From these observations, we concluded that the detected particles were members of small round structured virus (SRSV), and that they were implicated in the etiologically ill-defined outbreaks encountered. Prevalence of SRSV infections in these outbreaks was examined by electron microscopy. SRSV was positive in 83.8% of the outbreaks, and 96.4% of the cases. SRSV-positive outbreaks usually occurred during winter in contrast to bacterial outbreaks which often occurred in the summer season. Of 80 outbreaks examined, 53 were associated with the ingestion of oysters, and the remaining 27 mostly with food other than oysters. Oyster-associated outbreaks usually occurred on a small scale, while unassociated ones on diverse scales ranged from family clusters to large outbreaks.