17 research outputs found
Myocardial Impairment Detected by Late Gadolinium Enhancement in Hypertrophic Cardiomyopathy: Comparison with 99mTc-MIBI/Tetrofosmin and 123I-BMIPP SPECT
Purpose: Myocardial fibrosis is considered to be an important factor in myocardial dysfunction and sudden cardiac death in hypertrophic cardiomyopathy (HCM). The purpose of this study was to compare myocardial fibrosis detected by late gadolinium enhancement (LGE) on cardiac MRI with myocardial perfusion and fatty acid metabolism assessed by single photon emission computed tomography in HCM.Materials and Methods: We retrospectively evaluated 20 consecutive HCM patients (female, 7; mean age, 53.4 years) who underwent LGE, technetium-99m methoxyisobutylisonitrile/tetrofosmin (99mTc-MIBI/tetrofosmin), and iodine-123 beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP) imaging. We calculated the myocardium-to-lumen signal ratio (M/L) for LGE in 17 segments based on the American Heart Association statement. Scoring of 99mTc-MIBI/tetrofosmin (PI) and 123I-BMIPP (BM) was performed for each segment using a 5-point scale (0, normal; 4, highly decreased).Results: Nineteen of 20 patients (95%) and 153 of 340 segments (45%) showed LGE. M/Ls were 0.42ア・.16, 0.55ア・.17, and 0.65ア・.24 in PI0/BM0, PI0/BM1-4 and PI1-4/BM1-4, respectively. All M/Ls were significantly higher than that of a normal control (0.34ア・.14) (p<0.001).Conclusions: Myocardial fibrosis in HCM can occur despite normal perfusion and fatty acid metabolism, and is more strongly associated with disorders of fatty acid metabolism than with perfusion abnormalities. M/L may be a useful indicator of disease severity
Environmental impact on star-forming galaxies in a cluster during course of galaxy accretion
Galaxies change their properties as they assemble into clusters. In order to
understand the physics behind that, we need to go back in time and observe
directly what is occurring in galaxies as they fall into a cluster. We have
conducted a narrow-band and -band imaging survey on a cluster CL1604-D at
using a new infrared instrument SWIMS installed at the Subaru
Telescope. The narrow-band filter, NB1261, matches to H emission from
the cluster at . Combined with a wide range of existing data from
various surveys, we have investigated galaxy properties in and around this
cluster in great detail. We have identified 27 H emitters associated
with the cluster. They have significant overlap with MIPS 24m sources and
are located exclusively in the star forming regime on the rest-frame
diagram. We have identified two groups of galaxies near the cluster in the 2D
spatial distribution and the phase-space diagram, which are likely to be
in-falling to the cluster main body. We have compared various physical
properties of star forming galaxies, such as specific star formation rates
(burstiness) and morphologies (merger) as a function of environment; cluster
center, older group, younger group, and the field. As a result, a global
picture has emerged on how the galaxy properties are altered as they assemble
into a denser region. This includes the occurrence of mergers, enhancement of
star formation activity, excursion to the dusty starburst phase, and eventual
quenching to a passive phase.Comment: 19 pages, 15 figures. Accepted for publication in ApJ. Error bars in
Table 2 correcte
Food availability before aestivation governs growth and winter reproductive potential in the capital breeding fish, Ammodytes japonicus.
Capital breeders develop gametes by using energy that was stored before the spawning season. Energy is allocated to growth and reproduction, and limited food availability affects the balance of energy allocation, especially in fish that mature within a year, such as western sand lance (Ammodytes japonicus). This species aestivates without feeding until winter spawning and utilize energy stores that were accumulated prior to aestivation for maturation and spawning. This study aimed to evaluate the growth, energy storage, maturation rate, and reproduction of A. japonicus in response to food availability before aestivation. We conducted laboratory experiments in which young-of-the-year A. japonicus were fed at rates of 4% and 1% of their body weight per day; assigned as high and low ration groups, respectively. In June, body length was found to be significantly larger in the high ration group than in the low ration group, but the somatic condition did not differ significantly between the groups. Maturation rates and average fecundities were 1.0 and 6297 in the high ration group and 0.8 and 2251 in the low ration group, respectively. These results indicate that food availability before aestivation strongly governs the reproductive potential of A. japonicus, and suggest the involvement of mechanisms in the inter-annual recruitment variation in sand lance species
Potential impact of predation by larval Spanish mackerel on larval anchovy in the central Seto Inland Sea, Japan
Japanese anchovy is used as an essential dried fish material from the larval to adult stages. In the central Seto Inland Sea, Japan, the catch of larval anchovy has markedly decreased to <3.9% of the maximum recorded in 2002 since 2013; however, the reason causing this reduction has not been well understood. The abundance of recruit fish, including larvae and early juveniles, has decreased in the last decade, despite abundant eggs, suggesting that the majority of larvae do not survive before recruitment. In contrast, the stock of Japanese Spanish mackerel, whose larvae are the major predator of larval anchovy, has increased in the Seto Inland Sea. It is hypothesized that an increase in the density of Spanish mackerel may have a top-down control on the decrease in anchovy recruitment by an increase in predation opportunities. In this study, we investigated the abundance of Spanish mackerel and anchovy larvae using a bongo net in the field in 2018 and 2019. The average densities of larvae in late May were 1.5–3.3 individuals (inds) / 100 m3 and 1,058–1,346 inds / 100 m3 for the Spanish mackerel and the anchovy, respectively; both were higher than those in 2002–2005. We constructed a Stella model, simulating the growth and survival of larval anchovy until they reached the commercial sizes by taking into account consumption by larval Spanish mackerel. The model suggested that the consumption of larval anchovy by larval Spanish mackerel accounted for <4% of the initial abundance of anchovy in 2018, which was not greater than that in 2005. In contrast, the reduction in the growth rates of larval anchovy due to reduced maternal conditions can adversely affect their survival. Thus, the results did not fully support the hypothesis mentioned above.This work was partly supported by the Fisheries Agency of Japan and Japan Fisheries Researc