Publications by authors named "Nagamatsu A"

As a space project, in "Stem Cells" by the Japan Aerospace Exploration Agency (JAXA), frozen mouse ES cells were stored on the International Space Station (ISS) in the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) for 1584 days. After taking these cells back to the ground, the cells were thawed and cultured, and their gene expressions were comprehensively analyzed using RNA sequencing in order to elucidate the early response of the cells to long-time exposure to space radiation consisting of various ionized particles. The comparisons of gene expression involved in double-stranded break (DSB) repair were examined.

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Fenquinotrione is a novel rice herbicide that was discovered and developed by Kumiai Chemical Industry Co., Ltd. It can control a wide range of broadleaf and sedge weeds with excellent rice selectivity at 30 g a.

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Exposure to the space environment induces a number of pathophysiological outcomes in astronauts, including bone demineralization, sleep disorders, circadian clock dysregulation, cardiovascular and metabolic dysfunction, and reduced immune system function. A recent report describing experiments aboard the Space Shuttle mission, STS-132, showed that the level of melatonin, a hormone that provides the biochemical signal of darkness, was decreased during microgravity in an in vitro culture model. Additionally, abnormal lighting conditions in outer space, such as low light intensity in orbital spacecraft and the altered 24-h light-dark cycles, may result in the dysregulation of melatonin rhythms and the misalignment of the circadian clock from sleep and work schedules in astronauts.

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Nowadays, ordinary people can travel in space, and the possibility of extended durations in an environment such as moon of the Earth and Mars with higher space radiation exposures compared to past missions, is increasing. Until now, the physical doses of space radiation have been measured, but measurement of direct biological effects has been hampered by its low dose and low dose-rate effect. To assess the biological effects of space radiation, we launched and kept frozen mouse embryonic stem (ES) cells in minus eighty degree Celsius freezer in ISS (MELFI) on the International Space Station (ISS) for a maximum of 1,584 days.

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Fenquinotrione is a novel herbicide that can control a wide range of broadleaf and sedge weeds with excellent rice selectivity. We revealed that fenquinotrione potently inhibited the 4-hydroxyphenylpyruvate dioxygenase (HPPD) activity in with an IC of 44.7 nM.

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Space radiation may cause DNA damage to cells and concern for the inheritance of mutations in offspring after deep space exploration. However, there is no way to study the long-term effects of space radiation using biological materials. Here, we developed a method to evaluate the biological effect of space radiation and examined the reproductive potential of mouse freeze-dried spermatozoa stored on the International Space Station (ISS) for the longest period in biological research.

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Deep space exploration by humans has become more realistic, with planned returns to the Moon, travel to Mars, and beyond. Space radiation with a low dose rate would be a constant risk for space travelers. The combined effects of space radiation and partial gravity such as on the Moon and Mars are unknown.

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Space travel has advanced significantly over the last six decades with astronauts spending up to 6 months at the International Space Station. Nonetheless, the living environment while in outer space is extremely challenging to astronauts. In particular, exposure to space radiation represents a serious potential long-term threat to the health of astronauts because the amount of radiation exposure accumulates during their time in space.

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Aim: Muscle atrophy is a prognostic factor for patients with chronic liver disease (CLD) and hepatocellular carcinoma (HCC). The Liver Frailty Index (LFI) is a simple physical function test; however, an association between LFI and muscle mass remains unclear. We aimed to investigate the utility of LFI for predicting muscle atrophy in CLD patients with HCC.

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Aim: Walking speed and grip strength are parameters of muscle function; however, evaluating walking speed is not always available in clinical practice. We aimed to investigate the impact of walking speed on the evaluation of muscle dysfunction in chronic liver disease (CLD) patients with hepatocellular carcinoma (HCC).

Methods: We enrolled 107 consecutive CLD patients with HCC in this study (age 76 years [range 60-92 years]; female/male 39/68; body mass index 22.

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Background And Aim: Sarcopenia is a prognostic factor in hepatocellular carcinoma (HCC) patients. HCC patients who underwent transcatheter arterial chemoembolization (TACE) are at a risk of muscle atrophy. We aimed to investigate the effects of in-hospital exercise on muscle mass and factors associated with muscle hypertrophy in HCC patients who underwent TACE.

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Estimation of cosmic-ray doses is of great importance not only in aircrew and astronaut dosimetry but also in evaluation of background radiation exposure to public. We therefore calculated the cosmic-ray doses on Earth, Moon and Mars as well as inside spacecraft, using Particle and Heavy Ion Transport code System PHITS. The same cosmic-ray models and dose conversion coefficients were employed in the calculation to properly compare between the simulation results for different environments.

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If humans ever start to live permanently in space, assisted reproductive technology using preserved spermatozoa will be important for producing offspring; however, radiation on the International Space Station (ISS) is more than 100 times stronger than that on Earth, and irradiation causes DNA damage in cells and gametes. Here we examined the effect of space radiation on freeze-dried mouse spermatozoa held on the ISS for 9 mo at -95 °C, with launch and recovery at room temperature. DNA damage to the spermatozoa and male pronuclei was slightly increased, but the fertilization and birth rates were similar to those of controls.

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The incidence of traffic accidents in patients with chronic liver disease (CLD) is high in the USA. However, the characteristics of patients, including dietary habits, differ between Japan and the USA. The present study investigated the incidence of traffic accidents in CLD patients and the clinical profiles associated with traffic accidents in Japan using a data-mining analysis.

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Aims: Sarcopenia and physical disability assessed by a 6-min walking test (6MWT) are associated with poor prognosis of patients with chronic liver disease (CLD). However, CLD patients with hepatocellular carcinoma (HCC) mostly rest in bed during hospitalization. We aimed to investigate the effects of therapeutic exercise on liver function, 6MWT, and skeletal muscle mass during HCC treatment in patients with CLD.

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Eukaryotic chemotaxis is usually mediated by intracellular signals that tend to localize at the front or back of the cell. Such intracellular polarities frequently require no extracellular guidance cues, indicating that spontaneous polarization occurs in the signal network. Spontaneous polarization activity is considered relevant to the persistent motions in random cell migrations and chemotaxis.

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Aim:   In patients with chronic liver disease who are at risk of malnutrition, simple and useful assessments for nutritional status should be established for ordinary medical care. The prognostic nutritional index (PNI) and controlling nutritional status (CONUT) are simple assessments constructed of only two or three laboratory data. We aimed to describe the potential of PNI and CONUT as a nutritional assessment tool in patients with chronic liver disease.

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Background/aims: Esophageal varices are often seen in cirrhotic patients. Because endoscopic therapy for esophageal varices forces such patients to go on an extended fast until the endoscopic therapy occurs, physical and psychological stresses are induced. The aims of this study were to investigate the effects of a nutritional supplement before endoscopic therapy on such stresses, and on the safety of therapy.

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Classical genetic analysis has revealed that the determinate habit of soybean (Glycine max) is controlled by a recessive allele at the determinate stem (Dt1) locus. To dissect the molecular basis of the determinate habit, we isolated two orthologs of pea (Pisum sativum) TERMINAL FLOWER1a, GmTFL1a and GmTFL1b, from the soybean genome. Mapping analysis indicated that GmTFL1b is a candidate for Dt1.

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We evaluated the use of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) for the diagnosis of uterine sarcomas. FDG-PET combined with serum lactate dehydrogenase (LDH) levels were compared with FDG-PET alone for the diagnosis of leiomyosarcomas (LMS), which are the most difficult uterine sarcomas to diagnose. FDG-PET imaging of endometrial cancer (EC) was used as a reference.

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To identify DNA damage induced by space radiations such as the high linear energy transfer (LET) particles, phospho-H2AX (gammaH2AX) foci formation was analyzed in human cells frozen in an International Space Station freezer for 133days. After recovering the frozen sample to the earth, the cells were cultured for 30 min, and then fixed. Here we show a track of gammaH2AX positive foci in them by immuno-cytochemical methods.

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Space radiation hazards are recognized as a key concern for human space flight. For long-term interplanetary missions, they constitute a potentially limiting factor since current protection limits for low-Earth orbit missions may be approached or even exceeded. In such a situation, an accurate risk assessment requires knowledge of equivalent doses in critical radiosensitive organs rather than only skin doses or ambient doses from area monitoring.

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Changes in flavonoid content are often manifested as altered pigmentation in plant tissues. Two loci have been identified as controlling pigmentation in soybean pubescence. Of these, the T locus appears to encode flavonoid 3'-hydroxylase (F3'H) protein: the T and t alleles are associated with tawny and gray colors, respectively, in pubescence.

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Virus-induced gene silencing (VIGS) is a powerful tool for functional analysis of genes in plants. A wide-host-range VIGS vector, which was developed based on the Cucumber mosaic virus (CMV), was tested for its ability to silence endogenous genes involved in flavonoid biosynthesis in soybean. Symptomless infection was established using a pseudorecombinant virus, which enabled detection of specific changes in metabolite content by VIGS.

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