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If a hypothetical elementary particle called an axion exists, to solve the strong CP problem, a 57Fe nucleus in the solar core could emit a 14.4-keV monochromatic axion through the M1 transition. If such axions are once more transformed into photons by a 57Fe absorber, a transition edge sensor (TES) X-ray microcalorimeter should be able to detect them efficiently. We have designed and fabricated a dedicated 64-pixel TES array with iron absorbers for the solar axion search. In order to decrease the effect of iron magnetization on spectroscopic performance, the iron absorber is placed next to the TES while maintaining a certain distance. A gold thermal transfer strap connects them. We have accomplished the electroplating of gold straps with high thermal conductivity. The residual resistivity ratio (RRR) was over 23, more than eight times higher than a previous evaporated strap. In addition, we successfully electroplated pure-iron films of more than a few micrometers in thickness for absorbers and a fabricated 64-pixel TES calorimeter structure., 5 pages, 5 figures, published in IEEE Transactions on Applied Superconductivity on 8 March 2023

Volatile and organic-rich C-type asteroids may have been one of the main sources of Earth’s water. Our best insight into their chemistry is currently provided by carbonaceous chondritic meteorites, but the meteorite record is biased: only the strongest types survive atmospheric entry and are then modified by interaction with the terrestrial environment. Here we present the results of a detailed bulk and microanalytical study of pristine Ryugu particles, brought to Earth by the Hayabusa2 spacecraft. Ryugu particles display a close compositional match with the chemically unfractionated, but aqueously altered, CI (Ivuna-type) chondrites, which are widely used as a proxy for the bulk Solar System composition. The sample shows an intricate spatial relationship between aliphatic-rich organics and phyllosilicates and indicates maximum temperatures of ~30 °C during aqueous alteration. We find that heavy hydrogen and nitrogen abundances are consistent with an outer Solar System origin. Ryugu particles are the most uncontaminated and unfractionated extraterrestrial materials studied so far, and provide the best available match to the bulk Solar System composition.

Presented here are the observations and interpretations from a comprehensive analysis of 16 representative particles returned from the C-type asteroid Ryugu by the Hayabusa2 mission. On average Ryugu particles consist of 50% phyllosilicate matrix, 41% porosity and 9% minor phases, including organic matter. The abundances of 70 elements from the particles are in close agreement with those of CI chondrites. Bulk Ryugu particles show higher δ18O, Δ17O, and ε54Cr values than CI chondrites. As such, Ryugu sampled the most primitive and least-thermally processed protosolar nebula reservoirs. Such a finding is consistent with multi-scale H-C-N isotopic compositions that are compatible with an origin for Ryugu organic matter within both the protosolar nebula and the interstellar medium. The analytical data obtained here, suggests that complex soluble organic matter formed during aqueous alteration on the Ryugu progenitor planetesimal (several 10’s of km)

International audience; INTRODUCTION: Organic compounds in asteroids and comets contain information about the early history of the Solar System. They could also have delivered organic material to early Earth. The Hayabusa2 spacecraft visited the carbonaceous asteroid Ryugu and collected samples of its surface materials, which were brought to Earth in December 2020. RATIONALE: We investigated the macromolecular organic matter in the Ryugu samples, measuring its elemental, isotopic, and functional group compositions along with its small-scale structures and morphologies. Analytical methods used included spectro-microscopies, electron microscopy, and isotopic microscopy. We examined intact Ryugu grains and insoluble carbonaceous residues isolated by acid treatment of the Ryugu samples. RESULTS: Organic matter is abundant in the Ryugu grains, distributed as submicrometersized organic grains and as organic matter dispersed in matrix. The Ryugu organic matter consists of aromatic carbons, aliphatic carbons, ketones, and carboxyls. The functional group

C-type asteroids1 are considered to be primitive small Solar System bodies enriched in water and organics, providing clues to the origin and evolution of the Solar System and the building blocks of life. C-type asteroid 162173 Ryugu has been characterized by remote sensing2–7 and on-asteroid measurements8,9 with Hayabusa2 (ref. 10). However, the ground truth provided by laboratory analysis of returned samples is invaluable to determine the fine properties of asteroids and other planetary bodies. We report preliminary results of analyses on returned samples from Ryugu of the particle size distribution, density and porosity, spectral properties and textural properties, and the results of a search for Ca–Al-rich inclusions (CAIs) and chondrules. The bulk sample mainly consists of rugged and smooth particles of millimetre to submillimetre size, confirming that the physical and chemical properties were not altered during the return from the asteroid. The power index of its size distribution is shallower than that of the surface boulder observed on Ryugu11, indicating differences in the returned Ryugu samples. The average of the estimated bulk densities of Ryugu sample particles is 1,282 ± 231 kg m−3, which is lower than that of meteorites12, suggesting a high microporosity down to the millimetre scale, extending centimetre-scale estimates from thermal measurements5,9. The extremely dark optical to near-infrared reflectance and spectral profile with weak absorptions at 2.7 and 3.4 μm imply a carbonaceous composition with indigenous aqueous alteration, matching the global average of Ryugu3,4 and confirming that the sample is representative of the asteroid. Together with the absence of submillimetre CAIs and chondrules, these features indicate that Ryugu is most similar to CI chondrites but has lower albedo, higher porosity and more fragile characteristics.

Without a protective atmosphere, space-exposed surfaces of airless Solar System bodies gradually experience an alteration in composition, structure and optical properties through a collective process called space weathering. The return of samples from near-Earth asteroid (162173) Ryugu by Hayabusa2 provides the first opportunity for laboratory study of space-weathering signatures on the most abundant type of inner solar system body: a C-type asteroid, composed of materials largely unchanged since the formation of the Solar System. Weathered Ryugu grains show areas of surface amorphization and partial melting of phyllosilicates, in which reduction from Fe3+ to Fe2+ and dehydration developed. Space weathering probably contributed to dehydration by dehydroxylation of Ryugu surface phyllosilicates that had already lost interlayer water molecules and to weakening of the 2.7 µm hydroxyl (–OH) band in reflectance spectra. For C-type asteroids in general, this indicates that a weak 2.7 µm band can signify space-weathering-induced surface dehydration, rather than bulk volatile loss.

We developed a transition edge sensor (TES) microcalorimeter to measure high-energy gamma-rays in the range of up to several MeV. We performed gamma-ray irradiation experiments using this TES microcalorimeter fabricated with a cubic bismuth cut out (1 × 1 × 0.7 mm). As a result, we successfully achieved an energy resolution of 0.92 keV for 662-keV gamma rays (137Cs) and 0.97 keV for 1332-keV gamma rays (60Co). In addition, we investigated methods to reduce low-frequency noise based on the results obtained by comparing the count rates of pulses with different decay time.

Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples of the C-type asteroid (162173) Ryugu were retrieved by the Hayabusa2 spacecraft. We measured the mineralogy and bulk chemical and isotopic compositions of Ryugu samples. The samples are mainly composed of materials similar to those of carbonaceous chondrite meteorites, particularly the CI (Ivuna-type) group. The samples consist predominantly of minerals formed in aqueous fluid on a parent planetesimal. The primary minerals were altered by fluids at a temperature of 37° ± 10°C, about 5.2 − 0.7 + 0.8 million (statistical) or 5.2 − 2.1 + 1.6 million (systematic) years after the formation of the first solids in the Solar System. After aqueous alteration, the Ryugu samples were likely never heated above ~100°C. The samples have a chemical composition that more closely resembles that of the Sun’s photosphere than other natural samples do.

Objective: This study was designed to clarify the association of the MAFK polymorphisms (rs4268033, rs3735656, and rs10226620) with the degree of gastric mucosal atrophy and CDKN2A CpG methylation ...

Background CpG methylation of tumor suppressor genes occurs in the early stage of carcinogenesis. Detecting risk factors for aberrant CpG methylation is clinically important for predicting cancer development. DNA methyltransferase (DNMT) 3a is considered to play critical roles in the DNA methylation process during pathogenesis. In this study, we evaluated the association between DNMT3A polymorphisms (rs6733868 and rs13428812) and CpG methylation status in non-cancerous gastric mucosa. Methods We determined the DNMT3A genotype and CpG methylation status of 4 genes (p14ARF, p16INK4a, DAPK, and CDH1) in 510 subjects without gastric cancer. Helicobacter pylori (HP) infection status was determined by the rapid urease test, urea breath test, speculum examination, or serum antibody test. We determined the DNMT3A genotype using polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP). CpG methylation status was determined by methylation-specific polymerase chain reaction (MSP). When the methylated band was stronger than 10 ng/μL according to the DNA marker, we judged CpG island hypermethylation (CIHM) to be present. Associations between genotypes and susceptibilities were assessed by logistic regression analysis. Results The minor allele frequencies of both polymorphisms (rs6733868 and rs13428812) were lower in the CpG methylated groups of each of the 4 genes (p14ARF, p16INK4a, DAPK, and CDH1). Using a dominant genetic model, rs6733868 was significantly associated with the hypermethylation of each gene, whereas rs13428812 was associated with the methylation of 3 genes (all except p14ARF). When low-CIHM was defined as 1 or 2 CpG islands methylated and high-CIHM was defined as 3 or more CpG islands methylated, carrying the minor allele of rs6733868 was associated with both decreased low- and high-CIHM, and that of rs13428812 also was associated with a decrease. Comparing low-CIHM with high-CIHM, carrying the minor alleles of rs6733868 or rs13428812 was related to decreased susceptibility to high-CIHM. In HP-infected subjects, carrying the minor alleles of rs6733868 or rs13428812 had a significantly greater association with decreased susceptibility to high-CIHM. Conclusions Our study indicates that polymorphisms of DNMT3A are associated with the accumulation of gene methylation in gastric mucosa. Carrying the minor alleles of rs6733868 or rs13428812 inhibits aberrant gene methylations, which are typically enhanced by HP infection.

We are developing position-sensitive transition-edge sensor (TES) microcalorimeters (PoSTs) to detect gamma rays up to a few MeV. Each gamma-ray PoST consists of a long absorber with a TES on each end and works as a 1D imaging spectrometer. We fabricated PoSTs with 0.5 × 0.5 × 18.8 mm lead absorbers. We irradiated two PoST devices with gamma rays from a Cs-137 source. Gamma-ray pulses of the PoSTs show a strong correlation between the pulse height and the rise time. We divided the pulses in the 662 keV line into 12 groups after sorting them by rise time to determine effective pixels. We modeled the PoST device and compared the average pulses of the 12 effective pixels to numerical simulations. The actual pulses and simulated pulses were in good agreement.

A useful function, called group trigger, is implemented in a data acquisition system of a 240-pixel X-ray transition-edge sensor array to store simultaneous waveforms from any desired set of pixels. It works as a diagnostic tool which can record both primary pulses and associated crosstalk events with enough freedom to optimize the data output. Under a high rate of charged particle background, such as in an accelerator, investigating signals from any combination of trigger patterns for a particular event is of high importance. We utilized this function throughout an entire experiment at J-PARC, measuring kaonic atom X-rays in 2018. This was the first time a group trigger was applied to exotic-atom spectroscopy. In this experiment, the primary trigger was distributed to the four physical nearest neighbor pixels for practical purposes. The function clarified the effect of thermal and electrical cross talk from X-rays and charged particles, resulting in a better understanding of the behavior of the TES array in such a high-background environment.

We integrated a TES X-ray spectrometer with a charged kaon beam line at J-PARC to perform X-ray spectroscopy of kaonic helium atoms. Limited beam intensity and a broad beam spot size made it crucial to increase the detector acceptance angle as much as possible, requiring significant development. To this end, our TES system shared the same vacuum with a cryogenic system of the liquid helium experimental target. We also specially developed a target cell for liquid helium and a thinned aperture array on top of the TES detector. Additionally, thermal and magnetic shields and infrared filters were optimized in terms of a larger acceptance angle and energy resolution of the detector. The scientific campaign was performed in June, 2018, where the whole system was stably operated for almost one month.

We herein report a concept study of a transition edge sensor (TES) X-ray microcalorimeter array with two different thickness absorbers. We developed an energy-dispersive X-ray spectroscope (EDS) with a 64-pixel TES array and installed it on a scanning transmission electron microscope (STEM) for material analysis. One of the key applications of the proposed system is the microanalysis of astromaterials, for which the relative abundance of light elements such as boron, carbon, and oxygen against silicon are crucial. However, the line sensitivity below $$\sim$$∼ 500 eV for the our STEM TES EDS system was not enough to detect the X-ray from light elements because of the relatively high continuum emission and low detection efficiency, which occurs due to the X-ray window and the optical blocking filters. A simple solution to increase line sensitivity at low energy is the adoption of thin X-ray absorbers that leads to an improvement in the energy resolution. However, doing so causes the sensitivity to decrease for high energy lines. Utilizing the spot-size dependence of the polycapillary X-ray optics on energy, which are used in the STEM TES EDS system, we studied a design in which thin absorbers are distributed on the outer area of detector. We optimized the design using the raytracing analysis of optics. A thin (300 nm) absorber is placed on the 52 outer pixels, while a thick (3.5 $$\upmu$$μm) absorber is placed on the central 12 pixels. The thin pixels detect approximately 50–60% of the total counts in 0.1–2 keV, while the central thick pixels detect approximately 50–80% of the total counts in 2–10 keV. We also demonstrated the fabrication process of two-thickness absorber arrays.

C-type asteroids likely formed in the outer Solar System and were then scattered inwards during giant planet migration (Walsh et al., 2011). They may have transported volatiles to the inner Solar System and created the conditions suitable for life on Earth(Alexander, 2017). Carbonaceous chondrites are fragments from C-type asteroids and provide evidence that these generally organic-rich (Garvie and Buseck, 2007) bodies experienced extensive aqueous alteration early in Solar System history (Alexander et al., 2014). On 6th December 2020, ~5.4g of material was delivered to Earth from the C-type asteroid 162173 Ryugu by the Hayabusa2 spacecraft (Yada et al., 2021). Here we present the results of an integrated bulk and micro-analytical study of Ryugu particles, which provides a unique insight into the interrelationship between aliphatic-rich organics and surrounding hydrous minerals at a sub-micrometer scale. This dataset has clear implications for better understanding the origin and early evolution of Solar System organic matter and demonstrates that Ryugu particles are among the most uncontaminated extraterrestrial materials so far studied.

Several issues in developing transition edge sensor (TES) microcalorimeters for the search of monochromatic solar axions expected at 14.4 keV are studied. The potential problem of developing TES’s of this purpose is in that an axion absorber of $$^{57}$$Fe must be placed in close vicinity of a TES. We estimated the minimum distance to avoid magnetic interference from iron using magnetic FEM simulations, and found it 30 $$\upmu $$m for an iron of 5 $$\upmu $$m thickness. We fabricated a TES with a 10 $$\upmu $$m thick iron membrane separated by 60 $$\upmu $$m. We confirmed the superconducting transition for this TES. However, both the residual normal resistance and the transition temperature was different from those of TES without iron. We also estimated the low-temperature thermal conductivity of an iron membrane by measuring the low-temperature electrical resistance and by applying the Wiedemann–Franz law. We estimated the pulse-shape dependency on the interaction position within the $$^{57}$$Fe converted using thermal FEM simulations. We found that the pulse-shape variations will limit the energy resolution to about 30 eV FWHM.

To show the technical feasibility of high-frequency and broadband anti-reflection (AR) coating for silicon optics in millimeter wavelengths, we fabricated a prototype of the four-layer sub-wavelength structure (SWS) using a combination of deep reactive ion etching (DRIE) and dicing processes. We also fabricated a three-layer SWS using a multi-layer DRIE technique. The described processes allow to obtain physical prototypes that are close enough to those designed that their simulated reflectances are slightly worse than expected. The simulations of the obtained three- and four-layer prototype showed the averaged reflectances of 5.2 % at 150–450 GHz and 3.7 % at 100–450 GHz, while the designed SWSs showed 1.6 % and 2.0 %, respectively.

We developed broadband antireflection structures for millimeter-wave and submillimeter-wave applications, particularly cryogenic applications. The structures were fabricated on silicon using deep reactive ion etching. Three-layer subwavelength structures were fabricated on both sides of a silicon plate with an area of 20 m m 2 . The transmittances of the structures were measured at 28 K. The average transmittance was 97.6% in the frequency range of 200–450 GHz.

C-type asteroids are considered to be primitive small Solar-System bodies enriched in water and organics, providing clues for understanding the origin and evolution of the Solar System and the building blocks of life. C-type asteroid 162173 Ryugu has been characterized by remote sensing and on-asteroid measurements with Hayabusa2, but further studies are expected by direct analyses of returned samples. Here we describe the bulk sample mainly consisting of rugged and smooth particles of millimeter to submillimeter size, preserving physical and chemical properties as they were on the asteroid. The particle size distribution is found steeper than that of surface boulders11. Estimated grain densities of the samples have a peak around 1350 kg m-3, which is lower than that of meteorites suggests a high micro-porosity down to millimeter-scale, as estimated at centimeter-scale by thermal measurements. The extremely dark optical to near-infrared reflectance and the spectral profile with weak absorptions at 2.7 and 3.4 microns implying carbonaceous composition with indigenous aqueous alteration, respectively, match the global average of Ryugu, confirming the sample’s representativeness. Together with the absence of chondrule and Ca-Al-rich inclusion of larger than sub-mm, these features indicate Ryugu is most similar to CI chondrites but with darker, more porous and fragile characteristics.

著者人数: 13名, Accepted: 2018-11-23, 資料番号: SA1180407000

We encountered three cases with incidental penetration of a straight Amsterdam-type bile duct plastic stent into the duodenal papilla. All patients had undergone insertion of a biliary plastic stent due to common bile duct stones. However, in all three cases, we observed penetration of the biliary plastic stent into the duodenal papilla just before the elective surgery or at the time of plastic stent replacement. We, therefore, performed stent dissection using a bipolar snare and were able to safely remove the plastic stents in all three cases. We believe that this is the first report of plastic stent dissection using a bipolar snare.

Background CDKN2A hypermethylation is among the major events associated with carcinogenesis and is also observed in non-neoplastic colonic mucosa in patients with ulcerative colitis (UC). Macrophage migration inhibitory factor (MIF) plays a crucial role in promoting gastrointestinal inflammation characteristic of UC. The aim of this study is to explore associations between CDKN2A methylation status and MIF polymorphisms (rs755622 and rs5844572). Methods One hundred and fifty-nine patients diagnosed with UC were enrolled in this study. The methylation status of p14ARF and p16INK4a was determined by MSP; MIF genotypes were identified by PCR-SSCP. Results We found no differences with respect to mean age, gender, clinical type (chronic continuous or relapse/remitting), or extent of disease among the patients with methylated and unmethylated p14ARF or p16INK4a. Carrying the rs755622 C allele indicated a significantly higher risk for p14ARF methylation (odds ratio (OR), 2.16; 95% confidence interval (CI), 1.08–4.32; p = 0.030); similarly, carrying the rs5844572 7-repeat allele indicated a significantly higher risk for p16INK4a methylation (OR, 2.57; 95% CI, 1.26–5.24; p = 0.0094) after an adjusted regression analysis. The carriers of the rs755662 C allele or the rs5844572 7-repeat allele were both at a significantly higher risk for methylation of both p14ARF and p16INK4a when compared to the cohort in which neither of the genes were methylated (OR, 2.70; 95% CI, 1.22–6.01; p = 0.015 and OR, 2.87; 95% CI, 1.25–6.62; p = 0.013, respectively). Additionally, carrying rs755622 C allele was significantly associated with CIHM in chronic continuous of clinical type and total colitis (OR, 25.9; 95% CI, 2.55–262.6; p = 0.0059 and OR, 4.38; 95% CI, 1.12–17.2; p = 0.034, respectively), and carrying 7-repeat allele of rs5844572 was significantly associated in chronic continuous type (OR, 14.5; 95%CI, 1.46–144.3; p = 0.022). Conclusions Taken together, our findings suggest that MIF genotypes associated with inflammation may also be involved in promoting carcinogenesis via CDKN2A hypermethylation in patients diagnosed with UC.

著者人数: 11名, Accepted: 2018-06-25, 資料番号: SA1180164000

The low-lying isomeric state of ^{229}Th provides unique opportunities for high-resolution laser spectroscopy of the atomic nucleus. We determine the energy of this isomeric state by taking the absolute energy difference between the excitation energy required to populate the 29.2-keV state from the ground state and the energy emitted in its decay to the isomeric excited state. A transition-edge sensor microcalorimeter was used to measure the absolute energy of the 29.2-keV γ ray. Together with the cross-band transition energy (29.2 keV→ground) and the branching ratio of the 29.2-keV state measured in a recent study, the isomer energy was determined to be 8.30±0.92 eV. Our result is in agreement with the latest measurements based on different experimental techniques, which further confirms that the isomeric state of ^{229}Th is in the laser-accessible vacuum ultraviolet range.

A 65-year-old man was admitted complaining of high fever and pain in the right lower abdomen. An ileocolonic side-to-end anastomosis had been performed 38 years previously for an abscess in a colonic diverticulum. On the current admission, findings on contrast-enhanced computed tomography suggested an amebic liver abscess and intestinal amebiasis. Colonoscopy revealed an irregularly shaped ulcer and false membrane in the ileal blind end of the ileocolonic anastomosis. Amebic trophozoites were seen by rapid microscopy. Amebiasis in the blind end of the ileum has rarely been reported. This case is of particular interest because the intestinal amebiasis also led to a liver abscess.

Accepted: 2019-02-09, 資料番号: SA1180382000

The aim of the present study was to investigate whether single nucleotide polymorphisms in the DNMT3A gene are associated with susceptibility to gastric cancer in the Japanese population. The present case-control study examined the associations between single nucleotide polymorphisms (rs6733868 and rs13428812) in DNMT3A and cancer susceptibility in 343 patients with gastric cancer and 708 subjects without gastric malignancies on upper gastro-duodenal endoscopy. Of 708 controls, 409 were classified into two groups histologically: 99 cases with and 310 cases without gastric mucosal atrophy. Overall, homozygosity for the DNMT3A rs6733868 minor allele was significantly associated with a reduced risk of gastric cancer (odds ratio [OR], 0.621; 95% confidence interval [CI], 0.402-0.958; P=0.031), especially of the intestinal type (OR, 0.494; 95% CI, 0.274-0.890; P=0.019). In subjects >60 years, rs6733868 minor allele homozygosity was significantly associated with gastric cancer susceptibility. Carriers of the rs6733868 minor allele had a reduced risk of severe gastric mucosal atrophy (OR, 0.495; 95% CI, 0.299-0.826; P=0.0069). In addition, the number of minor alleles of both rs6733868 and rs13428812 was significantly correlated with the risk of Helicobacter pylori (HP) infection (P=0.0070 and P=0.0050, respectively). However, rs13428812 was not associated with severe gastric mucosal atrophy or gastric carcinogenesis. The present results suggest that DNMT3A polymorphisms serve roles in the progression from HP infection to gastric mucosal atrophy and gastric carcinogenesis in terms of degree and manner.

We have succeeded in operating a transition-edge sensor (TES) spectrometer and evaluating its performance at the SPring-8 synchrotron x-ray light source. The TES spectrometer consists of a 240 pixel National Institute of Standards and Technology (NIST) TES system, and 220 pixels are operated simultaneously with an energy resolution of 4 eV at 6 keV at a rate of ∼1 c/s pixel-1. The tolerance for high count rates is evaluated in terms of energy resolution and live time fraction, leading to an empirical compromise of ∼2 × 103 c/s (all pixels) with an energy resolution of 5 eV at 6 keV. By utilizing the TES's wideband spectroscopic capability, simultaneous multi-element analysis is demonstrated for a standard sample. We conducted x-ray absorption near-edge structure (XANES) analysis in fluorescence mode using the TES spectrometer. The excellent energy resolution of the TES enabled us to detect weak fluorescence lines from dilute samples and trace elements that have previously been difficult to resolve due to the nearly overlapping emission lines of other dominant elements. The neighboring lines of As Kα and Pb Lα2 of the standard sample were clearly resolved, and the XANES of Pb Lα2 was obtained. Moreover, the x-ray spectrum from the small amount of Fe in aerosols was distinguished from the spectrum of a blank target, which helps us to understand the targets and the environment. These results are the first important step for the application of high resolution TES-based spectroscopy at hard x-ray synchrotron facilities.

Accepted: 2016-03-02, 資料番号: SA1150324000

著者人数: 14名, Accepted: 2016-02-17, 資料番号: SA1150322000

Accepted: 2016-02-03, 資料番号: SA1150329000

The aim of the present study was to investigate whether single nucleotide polymorphisms in the DNMT3A gene are associated with susceptibility to gastric cancer in the Japanese population. The present case-control study examined the associations between single nucleotide polymorphisms (rs6733868 and rs13428812) in DNMT3A and cancer susceptibility in 343 patients with gastric cancer and 708 subjects without gastric malignancies on upper gastro-duodenal endoscopy. Of 708 controls, 409 were classified into two groups histologically: 99 cases with and 310 cases without gastric mucosal atrophy. Overall, homozygosity for the DNMT3A rs6733868 minor allele was significantly associated with a reduced risk of gastric cancer (odds ratio [OR], 0.621; 95% confidence interval [CI], 0.402–0.958; P=0.031), especially of the intestinal type (OR, 0.494; 95% CI, 0.274–0.890; P=0.019). In subjects >60 years, rs6733868 minor allele homozygosity was significantly associated with gastric cancer susceptibility. Carriers of the rs6733868 minor allele had a reduced risk of severe gastric mucosal atrophy (OR, 0.495; 95% CI, 0.299–0.826; P=0.0069). In addition, the number of minor alleles of both rs6733868 and rs13428812 was significantly correlated with the risk of Helicobacter pylori (HP) infection (P=0.0070 and P=0.0050, respectively). However, rs13428812 was not associated with severe gastric mucosal atrophy or gastric carcinogenesis. The present results suggest that DNMT3A polymorphisms serve roles in the progression from HP infection to gastric mucosal atrophy and gastric carcinogenesis in terms of degree and manner.

Accepted: 2017-01-08, 資料番号: SA1160294000

AIM To investigate whether single nucleotide polymorphisms in maf protein K (MAFK), which encodes the MAFK, lead to increased susceptibility to ulcerative colitis in the Japanese population. METHODS This case control study examined the associations between MAFK single nucleotide polymorphisms (rs4268033 G>A, rs3735656 T>C and rs10226620 C>T) and ulcerative colitis susceptibility in 174 patients with ulcerative colitis (UC) cases, and 748 subjects without no lower abdominal symptoms, diarrhea or hematochezia (controls). In addition, as the second controls, we set 360 subjects, who have an irregular bowel movement without abnormal lower endoscopic findings (IBM controls). RESULTS The genotype frequency of rs4268033 AA and allelic frequency of the rs4268033A allele were significantly higher in the UC cases than in both controls (P = 0.0005 and < 0.0001, P = 0.015 and 0.0027 vs controls and IBM controls, respectively). Logistic regression analysis after adjustment for age and gender showed that the rs4268033 AA and rs3735656 CC genotypes were significantly associated with susceptibility to UC development (OR = 2.63, 95%CI: 1.61-4.30, P = 0.0001 and OR = 1.81; 95%CI: 1.12-2.94, P = 0.015, respectively). Similar findings were observed by the comparison with IBM controls. In addition, the rs4268033 AA genotype was significantly associated with all phenotypes of UC except early onset. There was no significant association between rs10226620 and ulcerative colitis. CONCLUSION Our results provide the first evidence that MAFK genetic polymorphisms are significantly associated with susceptibility to UC development. In particular, rs4268033 is closely associated with an increased risk for the development of UC.

Any increase in beta-lactam-resistant Haemophilus influenzae is a serious problem in respiratory and otolaryngology medicine. In this study, we examined the antibiotic susceptibility and genotype of 457 clinical Haemophilus influenzae strains isolated in Hokkaido Prefecture, Japan. Strains with beta-lactam-resistant mutations in gene encoding penicillin-binding protein 3 were more frequently found in lower respiratory tract specimens (sputa) than in upper respiratory tract specimens, such as rhinorrhea. The existence of the TEM-1 beta-lactamase gene occurred more frequently in adult patients than in pediatric patients. The results suggest that beta-lactam-resistant or nonsusceptible strains are more prevalent in adult patients with respiratory diseases. We observed only a very few strains which were nonsuscpetible to third-generation cephalosporins (CEPs) and carbapenems. However, 12%-13% of the strains were shown to be resistant to penicillins and second-generation CEPs, and approximately 4% of the strains were shown to be nonsusceptible to fourth-generation CEPs. In addition, we identified tetracycline-resistant (2.8%), chloramphenicol-resistant (0.6%), clarithromycin-resistant (2.6%), and fluoroquinolone-nonsusceptible (approximately 2%) H. influenzae strains.

We examined the macrolide susceptibility and the presence of macrolide-resistance genes in 780 Streptococcus pneumoniae strains that were isolated and collected at trunk hospitals and commercial clinical laboratories in Hokkaido prefecture, Japan, between 1999 and 2003. Of the 780 strains, 57.0% and 49.6% were found to bear the macrolide-resistance genes erm(B) and mef(A), respectively, while 87.9% had either or both of these genes. The mef(A)-positive strains were more frequently found in patients who were younger than 10 years (43.4%) compared to patients who were 10 years or older (30.3%), whereas the erm(B)-positive strains were similarly frequent in both groups (57.2% vs 54.9%). Strains that were extremely resistant to erythromycin (≥256μg/ml) were frequently found in strains isolated at trunk hospitals but were rarely found in strains that had been collected at commercial clinical laboratories. In conclusion, the high frequency of emergence of macrolide resistance in S. pneumoniae strains was similar to reports from other areas of Japan and other east Asian countries. However, the distribution of resistant genes to macrolides and the distribution of the minimum inhibitory concertrations (MICs) differed depending on patients’ ages and depending on whether the strains were isolated at trunk hospitals or commercial clinical laboratories.

Genetic polymorphisms of MAFK, encoding a small Maf protein, are associated with susceptibility to ulcerative colitis in Japan

The Japanese ASTRO-H mission, planned to be launched in 2014, will carry several instruments for covering a wide energy range from a few keV to 600 keV. Among them there are four thin-foil-nested Wolter-I X-ray telescopes. Two of them are Soft X-ray Telescopes (SXTs) covering up to ~12 keV. Each of them focuses an image on the focal plane detectors of the CCD camera (SXI) and the calorimeter (SXS-XCS), respectively. In 2011, we performed a ground calibration of a quadrant engineering model (EM) of SXT that was fabricated at MASA's Goddard Space Flight Center (GSFC). The ground calibration was made with a combination of the measurements at the GSFC and Institute of Space and Astronautical Science (ISAS) facilities. In this paper we report the results of the calibration at the ISAS 30m beamline facility. We used a raster san method with a pencil beam at the baseline length of 30m. An effective area and angular resolution of the EM quadrant were measured. The effective area is 147 cm 2 at 1.49 keV and 116 cm 2 at 4.51 keV, respectively, while the angular longer by ~20mm from nominal length. We also measured imaging performance in separate parts of nested mirrors. The angular resolution of parts at outer radius is larger than those at inner radius, and the quadrant have different focal lengths in radius.

This study was conducted by the Japanese Society of Chemotherapy and is the first nationwide study on bacterial pathogens isolated from patients with urinary tract infections at 28 hospitals throughout Japan between January 2008 and June 2008. A total of 688 bacterial strains were isolated from adult patients with urinary tract infections. The strains investigated in this study are as follows: Enterococcus faecalis (n = 140), Escherichia coli (n = 255), Klebsiella pneumoniae (n = 93), Proteus mirabilis (n = 42), Serratia marcescens (n = 44), and Pseudomonas aeruginosa (n = 114). The minimum inhibitory concentrations of 39 antibacterial agents used for these strains were determined according to the Clinical and Laboratory Standards Institute (CLSI) manual. All Enterococcus faecalis strains were susceptible to ampicillin and vancomycin. Although a majority of the E. faecalis strains were susceptible to linezolid, 11 strains (7.8%) were found to be intermediately resistant. The proportions of fluoroquinolone-resistant Enterococcus faecalis, Escherichia coli, Proteus mirabilis, and S. marcescens strains were 35.7%, 29.3%, 18.3%, and 15.2%, respectively. The proportions of E. coli, P. mirabilis, K. pneumoniae, and S. marcescens strains producing extended-spectrum β-lactamase were 5.1%, 11.9%, 0%, and 0%, respectively. The proportions of Pseudomonas aeruginosa strains resistant to carbapenems, aminoglycosides, and fluoroquinolones were 9.2%, 4.4%, and 34.8%, respectively, and among them, 2 strains (1.8%) were found to be multidrug resistant. These data present important information for the proper treatment of urinary tract infections and will serve as a useful reference for periodic surveillance studies in the future.

A total of 18,639 clinical isolates in 19 species collected from 77 centers during 2004 in Japan were tested for their susceptibility to fluoroquinolones (FQs) and other selected antibiotics. The common respiratory pathogens, Streptococcus pyogenes, Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae showed a high susceptible rate against FQs. The isolation rate of beta lactamase non-producing ampicillin-resistant H. influenzae was approximately three times as large as those of western countries. Most strains of Enterobacteriaceae were also susceptible to FQs. The resistance rate of Escherichia coli against FQs has however been rapidly increasing so far as we surveyed since 1994. The FQs-resistant rate in methicillin-resistant Staphylococcus aureus (MRSA) showed approximately 90% except for 36%. of sitafloxacin while FQs-resistant rate in methicillin-susceptible S. aureus (MSSA) was around 5%. The FQs-resistant rate of methicillin-resistant coagulase negative Staphylococci (MRCNS) was also higher than that of methicillin-susceptible coagulase negative Staphylococci (MSCNS), however, it was lower than that of MRSA. In Pseudomonas aeruginosa clinical isolates, 32-34% from UTI and 15-19% of from RTI was resistant to FQs. Acinetobacter spp. showed a high susceptibility to FQs. Although FQs-resistant Neisseria gonorrhoeae have not been increased in western countries, it is remarkably high in Japan. In this survey, isolates of approximately 85% was resistant to FQs.

The Hayabusa2 spacecraft returned to Earth from the asteroid 162173 Ryugu on 6 December 2020. One day after the recovery, the gas species retained in the sample container were extracted and measured on-site and stored in gas collection bottles. The container gas consists of helium and neon with an extraterrestrial ³He/⁴He and ²⁰Ne/²²Ne ratios, along with some contaminant terrestrial atmospheric gases. A mixture of solar and Earth’s atmospheric gas is the best explanation for the container gas composition. Fragmentation of Ryugu grains within the sample container is discussed on the basis of the estimated amount of indigenous He and the size distribution of the recovered Ryugu grains. This is the first successful return of gas species from a near-Earth asteroid., 「はやぶさ2」ミッションによる世界初の小惑星からのガスサンプル：リュウグウからのたまて箱. 京都大学プレスリリース. 2022-10-21.