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result(s) for
"Akiko Miyazaki"
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Denosumab versus romosozumab for postmenopausal osteoporosis treatment
2021
Denosumab and romosozumab, a recently approved new drug, are effective and widely known molecular-targeted drugs for postmenopausal osteoporosis treatment. However, no studies have directly compared their therapeutic effects or safety in postmenopausal osteoporosis. This retrospective observational registry study compared the efficacy of 12-month denosumab or romosozumab treatment in postmenopausal osteoporosis patients. The primary outcome was the change in bone mineral density (BMD) at the lumbar spine. Secondary outcomes included BMD changes at the total hip and femoral neck, changes in bone turnover markers, and adverse events. Propensity score matching was employed to assemble patient groups with similar baseline characteristics. Sixty-nine patients each received either denosumab or romosozumab for 12 months. The mean 12-month percentage change from baseline in lumbar spine BMD was 7.2% in the denosumab group and 12.5% in the romosozumab group, indicating a significant difference between the groups. The percentage changes in BMD at both the total hip and femoral neck were also significantly higher at 12 months in the romosozumab group than in the denosumab group. In denosumab patients, bone formation and bone resorption markers were significantly decreased at 6 and 12 months from baseline. In the romosozumab group, the bone formation marker was significantly increased at 6 months and then returned to baseline, while the bone resorption marker was significantly decreased at both time points. Adverse events were few and predominantly minor in both groups, with no remarkable difference in the incidence of new vertebral fractures. Romosozumab showed a higher potential for improving BMD than denosumab in this clinical study of postmenopausal osteoporosis patient treatment.
Journal Article
Pentosidine and carboxymethyl-lysine associate differently with prevalent osteoporotic vertebral fracture and various bone markers
by
Suzuki, Takako
,
Saito, Mitsuru
,
Shiraki, Masataka
in
692/163
,
692/699/317
,
Advanced glycosylation end products
2020
Pentosidine (PEN) and carboxymethyl-lysine (CML) are well-recognized advanced glycation end products (AGEs). However, how these AGEs affect the pathophysiology of osteoporosis and osteoporotic fractures remains controversial. This cross-sectional study aimed to investigate the associations of PEN and CML with bone markers, bone mineral density (BMD), and osteoporotic fractures in postmenopausal women from the Nagano Cohort Study. A total of 444 Japanese postmenopausal outpatients (mean ± standard deviation age: 69.8 ± 10.2 years) were enrolled after the exclusion of patients with acute or severe illness or secondary osteoporosis. The relationships among urinary PEN and serum CML levels, various bone markers, lumbar and hip BMD, and prevalent vertebral and long-bone fractures were evaluated. PEN associated significantly with prevalent vertebral fracture after adjustment for other confounders (odds ratio [OR] 1.59, 95% confidence interval [CI] 1.22–2.07;
P
< 0.001), but not with lumbar BMD. In contrast, a significant negative correlation was found between CML and lumbar BMD (
r
= − 0.180;
P
< 0.001), and this relationship was significant after adjustment for confounders (OR 0.84, 95% CI 0.76–0.93;
P
< 0.01). Although patients with prevalent vertebral fracture had significantly higher CML levels, the association between CML and prevalent vertebral fracture did not reach significance in the multivariate regression model. Both PEN and CML may play important roles in bone health for postmenopausal women, possibly via different mechanisms.
Journal Article
Uracil in the carbonaceous asteroid (162173) Ryugu
by
Takano, Yoshinori
,
Saiki, Takanao
,
Nakazawa, Satoru
in
140/58
,
639/33/445/3929
,
639/33/445/848
2023
The pristine sample from the near-Earth carbonaceous asteroid (162173) Ryugu collected by the Hayabusa2 spacecraft enabled us to analyze the pristine extraterrestrial material without uncontrolled exposure to the Earth’s atmosphere and biosphere. The initial analysis team for the soluble organic matter reported the detection of wide variety of organic molecules including racemic amino acids in the Ryugu samples. Here we report the detection of uracil, one of the four nucleobases in ribonucleic acid, in aqueous extracts from Ryugu samples. In addition, nicotinic acid (niacin, a B
3
vitamer), its derivatives, and imidazoles were detected in search for nitrogen heterocyclic molecules. The observed difference in the concentration of uracil between A0106 and C0107 may be related to the possible differences in the degree of alteration induced by energetic particles such as ultraviolet photons and cosmic rays. The present study strongly suggests that such molecules of prebiotic interest commonly formed in carbonaceous asteroids including Ryugu and were delivered to the early Earth.
Uracil was identified in the sample returned from the asteroid Ryugu. Having been provided to the early Earth as a component in such asteroidal materials, these molecules might have played a role for prebiotic chemical evolution on the early Earth
Journal Article
Preliminary analysis of the Hayabusa2 samples returned from C-type asteroid Ryugu
2022
C-type asteroids
1
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 sensing
2
–
7
and on-asteroid measurements
8
,
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 Ryugu
11
, 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 meteorites
12
, suggesting a high microporosity down to the millimetre scale, extending centimetre-scale estimates from thermal measurements
5
,
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 Ryugu
3
,
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.
The Hayabusa2 spacecraft returned 5.4 g of material from the asteroid Ryugu. A first analysis of the samples found an estimated density of 1,282 ± 231 kg m
−3
, considerably lower than even the most porous meteorites. Together with preliminary spectral analysis, these results indicate that Ryugu is similar to CI chondrites, but darker, more porous and more brittle.
Journal Article
Insights into the formation and evolution of extraterrestrial amino acids from the asteroid Ryugu
2023
All life on Earth contains amino acids and carbonaceous chondrite meteorites have been suggested as their source at the origin of life on Earth. While many meteoritic amino acids are considered indigenous, deciphering the extent of terrestrial contamination remains an issue. The Ryugu asteroid fragments (JAXA Hayabusa2 mission), represent the most uncontaminated primitive extraterrestrial material available. Here, the concentrations of amino acids from two particles from different touchdown sites (TD1 and TD2) are reported. The concentrations show that N,N-dimethylglycine (DMG) is the most abundant amino acid in the TD1 particle, but below detection limit in the other. The TD1 particle mineral components indicate it experienced more aqueous alteration. Furthermore, the relationships between the amino acids and the geochemistry suggest that DMG formed on the Ryugu progenitor body during aqueous alteration. The findings highlight the importance of aqueous chemistry for defining the ultimate concentrations of amino acids in primitive extraterrestrial samples.
Amino acid concentrations from 2 particles returned from different touchdown sites on the surface of Ryugu are reported. Differences in chemistry suggest different levels of aqueous alteration are recorded at the 2 sampled locations.
Journal Article
Chronic ingestion of soy peptide supplementation reduces aggressive behavior and abnormal fear memory caused by juvenile social isolation
by
Yamamoto, Naoki
,
Miyazaki, Akiko
,
Narita, Minoru
in
631/378/1595/2636
,
631/378/1831
,
631/378/3919
2024
Juvenile loneliness is a risk factor for psychopathology in later life. Deprivation of early social experience due to peer rejection has a detrimental impact on emotional and cognitive brain function in adulthood. Accumulating evidence indicates that soy peptides have many positive effects on higher brain function in rodents and humans. However, the effects of soy peptide use on juvenile social isolation are unknown. Here, we demonstrated that soy peptides reduced the deterioration of behavioral and cellular functions resulting from juvenile socially-isolated rearing. We found that prolonged social isolation post-weaning in male C57BL/6J mice resulted in higher aggression and impulsivity and fear memory deficits at 7 weeks of age, and that these behavioral abnormalities, except impulsivity, were mitigated by ingestion of soy peptides. Furthermore, we found that daily intake of soy peptides caused upregulation of postsynaptic density 95 in the medial prefrontal cortex and phosphorylation of the cyclic adenosine monophosphate response element binding protein in the hippocampus of socially isolated mice, increased phosphorylation of the adenosine monophosphate-activated protein kinase in the hippocampus, and altered the microbiota composition. These results suggest that soy peptides have protective effects against juvenile social isolation-induced behavioral deficits via synaptic maturation and cellular functionalization.
Journal Article
Influence of ice storage period before freezing on quality of frozen chub mackerel Scomber japonicus fillets and considerations regarding high-quality frozen sashimi products
2021
Achieving high quality levels of frozen chub mackerel Scomber japonicus sashimi products was examined using scientific analysis and sensory evaluation. Frozen fillets stored in ice for different periods before freezing were tested. Biochemical components in frozen fillets changed significantly within 14 h of ice storage. The thawing drip loss, physical properties, and ordinary meat color of thawed fillets stored in ice for ≥ 24 h prior to freezing changed significantly, suggesting quality degradation. Fillets frozen within 14 h of ice storage were as favorable as fillets frozen immediately after sacrificing. The frozen mackerel fillets that were assessed to be preferable had a K value of ≤ 2.8%.
Journal Article
A pristine record of outer Solar System materials from asteroid Ryugu’s returned sample
2022
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.
The sample taken from carbonaceous asteroid Ryugu and brought back to Earth by the Hayabusa2 spacecraft contains outer Solar System-derived materials uncontaminated by terrestrial processes. Even CI carbonaceous chondrites, despite their closeness to solar abundances, are not pristine.
Journal Article
Chondrule-like objects and Ca-Al-rich inclusions in Ryugu may potentially be the oldest Solar System materials
2023
Chondrule-like objects and Ca-Al-rich inclusions (CAIs) are discovered in the retuned samples from asteroid Ryugu. Here we report results of oxygen isotope, mineralogical, and compositional analysis of the chondrule-like objects and CAIs. Three chondrule-like objects dominated by Mg-rich olivine are
16
O-rich and -poor with Δ
17
O (=δ
17
O – 0.52 × δ
18
O) values of ~ –23‰ and ~ –3‰, resembling what has been proposed as early generations of chondrules. The
16
O-rich objects are likely to be melted amoeboid olivine aggregates that escaped from incorporation into
16
O-poor chondrule precursor dust. Two CAIs composed of refractory minerals are
16
O-rich with Δ
17
O of ~ –23‰ and possibly as old as the oldest CAIs. The discovered objects (<30 µm) are as small as those from comets, suggesting radial transport favoring smaller objects from the inner solar nebula to the formation location of the Ryugu original parent body, which is farther from the Sun and scarce in chondrules. The transported objects may have been mostly destroyed during aqueous alteration in the Ryugu parent body.
Chondrule-like objects and CAIs in the Ryugu samples are early generations of chondrules and possibly oldest solids in the Solar System. They were transported from the inner solar nebula to the formation location of the Ryugu original parent body.
Journal Article
PAHs, hydrocarbons, and dimethylsulfides in Asteroid Ryugu samples A0106 and C0107 and the Orgueil (CI1) meteorite
by
Takano, Yoshinori
,
Saiki, Takanao
,
Nakazawa, Satoru
in
Asteroid missions
,
Asteroids
,
Carbonaceous chondrites
2023
Evaluating the molecular distribution of organic compounds in pristine extraterrestrial materials is cornerstone to understanding the abiotic synthesis of organics and allows us to better understand the molecular diversity available during the formation of our solar system and before the origins of life on Earth. In this work, we identify multiple organic compounds in solvent extracts of asteroid Ryugu samples A0106 and C0107 and the Orgueil meteorite using two-dimensional gas chromatography and time-of-flight high resolution mass spectrometry (GC×GC–HRMS). Our analyses found similarities between the molecular distribution of organic compounds in Ryugu and the CI carbonaceous chondrite Orgueil. Specifically, several PAHs and organosulfides were found in Ryugu and Orgueil suggesting an interstellar and parent body origin for these compounds. We also evaluated the common relationship between Ryugu, Orgueil, and comets, such as Wild-2; however, until comprehensive compound-specific isotopic analyses for these organic species are undertaken, and until the effects of parent body processes and Earth’s weathering processes on meteoritic organics are better understood, their parent–daughter relationships will remain unanswered. Finally, the study of organic compounds in Ryugu samples and the curation practices for the future preservation of these unvaluable materials are also of special interest for future sample return missions, including NASA’s OSIRIS-REx asteroid sample return mission.
Journal Article