著者

Mariko Kawamura Rina Ishihara Kohei Oshiro Masaki Ishida

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.18, no.1, pp.60-62, 2023-02-28 (Released:2023-03-02)

参考文献数

15

---

We collected 43 medusae of Aurelia coerulea from Tanabe Bay, Wakayama, Japan, and measured the tubule lengths of 1,613 nematocysts at different growth stages: ephyra, juvenile, subadult, and adult. The median tubule lengths for ephyrae, juveniles, subadults, and adults were 72, 51, 79, and 58 µm, respectively. No nematocysts in ephyrae, juveniles, or subadults exceeded 200 µm in tubule length. In the tentacles of 15 adults, we detected nematocysts with tubule lengths exceeding 200 µm. The average proportion of nematocysts with long tubules was 9.1% in medusae with bell diameters of 110 mm or more, in contrast to only 1.0% in medusae with bell diameters of less than 110 mm. Among the 1,613 nematocysts examined, there were two different tubule groups with modes at 54 µm and 230 µm in length. Nematocysts in the short-tubule group were composed of microbasic euryteles and small isorhizas, whereas the long-tubule group was composed of only microbasic euryteles. These long tubules of microbasic euryteles can potentially penetrate not only large planktonic crustaceans but also human skin. The growth-related and intra-species variation in tubule length could also modify the degree of envenomation in humans.

著者

Masaki Ishida Jérôme Yerly Haruno Ito Masafumi Takafuji Shiro Nakamori Shinichi Takase Yoshito Ichiba Yoshiaki Komori Kaoru Dohi Davide Piccini Jessica A.M. Bastiaansen Matthias Stuber Hajime Sakuma

出版者

Japanese Society for Magnetic Resonance in Medicine

雑誌

Magnetic Resonance in Medical Sciences (ISSN:13473182)

巻号頁・発行日

pp.tn.2022-0086, (Released:2023-01-20)

参考文献数

17

被引用文献数

2

---

Free-running 5D whole-heart coronary MR angiography (MRA) is gaining in popularity because it reduces scanning complexity by removing the need for specific slice orientations, respiratory gating, or cardiac triggering. At 3T, a gradient echo (GRE) sequence is preferred in combination with contrast injection. However, neither the injection scheme of the gadolinium (Gd) contrast medium, the choice of the RF excitation angle, nor the dedicated image reconstruction parameters have been established for 3T GRE free-running 5D whole-heart coronary MRA. In this study, a Gd injection scheme, RF excitation angles of lipid-insensitive binominal off-resonance RF excitation (LIBRE) pulse for valid fat suppression and continuous data acquisition, and compressed-sensing reconstruction regularization parameters were optimized for contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence at 3T. Using this optimized protocol, contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence is feasible with good image quality at 3T.

著者

Hajime Sakuma Masaki Ishida

出版者

Japanese Society for Magnetic Resonance in Medicine

雑誌

Magnetic Resonance in Medical Sciences (ISSN:13473182)

巻号頁・発行日

pp.rev.2021-0033, (Released:2021-06-09)

参考文献数

86

被引用文献数

5

---

Stress myocardial perfusion imaging (MPI) is the preferred test in patients with intermediate-to-high clinical likelihood of coronary artery disease (CAD) and can be used as a gatekeeper to avoid unnecessary revascularization. Cardiac magnetic resonance (CMR) has a number of favorable characteristics, including: (1) high spatial resolution that can delineate subendocardial ischemia; (2) comprehensive assessment of morphology, global and regional cardiac functions, tissue characterization, and coronary artery stenosis; and (3) no radiation exposure to patients. According to meta-analysis studies, the diagnostic accuracy of perfusion CMR is comparable to positron emission tomography (PET) and perfusion CT, and is better than single-photon emission CT (SPECT) when fractional flow reserve (FFR) is used as a reference standard. In addition, stress CMR has an excellent prognostic value. One meta-analysis study demonstrated the annual event rate of cardiovascular death or non-fatal myocardial infarction was 4.9% and 0.8%, respectively, in patients with positive and negative stress CMR. Quantitative assessment of perfusion CMR not only allows the objective evaluation of regional ischemia but also provides insights into the pathophysiology of microvascular disease and diffuse subclinical atherosclerosis. For accurate quantification of myocardial perfusion, saturation correction of arterial input function is important. There are two major approaches for saturation correction, one is a dual-bolus method and the other is a dual-sequence method. Absolute quantitative mapping with myocardial perfusion CMR has good accuracy in detecting coronary microvascular dysfunction. Flow measurement in the coronary sinus (CS) with phase contrast cine CMR is an alternative approach to quantify global coronary flow reserve (CFR). The measurement of global CFR by quantitative analysis of perfusion CMR or flow measurement in the CS permits assessment of microvascular disease and diffuse subclinical atherosclerosis, which may provide improved prediction of future event risk in patients with suspected or known CAD. Multi-institutional studies to validate the diagnostic and prognostic values of quantitative perfusion CMR approaches are required.

著者

Masafumi Takafuji Masaki Ishida Satoshi Nakamura Kei Nakata Haruno Ito Takanori Kokawa Kensuke Domae Suguru Araki Shiro Nakamori Junko Ishiura Kaoru Dohi Hajime Sakuma

出版者

Japanese Society for Magnetic Resonance in Medicine

雑誌

Magnetic Resonance in Medical Sciences (ISSN:13473182)

巻号頁・発行日

pp.mp.2023-0018, (Released:2023-09-28)

参考文献数

37

---

Purpose: The purposes of this study were to compare global coronary flow reserve (CFR) between patients with idiopathic dilated cardiomyopathy (DCM) and risk-matched controls using cardiac MRI (CMR), and to evaluate the relationship between global CFR and CMR left ventricular (LV) parameters.Methods: Twenty-six patients with DCM and 26 risk-matched controls who underwent comprehensive CMR examination, including stress-rest coronary sinus flow measurement by phase contrast (PC) cine CMR were retrospectively studied. LV peak global longitudinal, radial, and circumferential strains (GLS, GRS, and GCS) were determined by feature tracking.Results: Patients with DCM had significantly lower global CFR compared with the risk-matched controls (2.87 ± 0.86 vs. 4.03 ± 1.47, P = 0.001). Among the parameters, univariate linear regression analyses revealed significant correlation of global CFR with LV end-diastolic volume index (r = –0.396, P = 0.045), LV mass index (r = –0.461, P = 0.018), GLS (r = –0.558, P = 0.003), and GRS (r = 0.392, P = 0.047). Multiple linear regression analysis revealed GLS as the only independent predictor of global CFR (standardized β = –0.558, P = 0.003).Conclusion: Global CFR was significantly impaired in patients with idiopathic DCM and independently associated with LV GLS, suggesting that microvascular dysfunction may contribute to deterioration of LV function in patients with idiopathic DCM.

著者

Keishi Moriwaki Tetsushiro Takeuchi Naoki Fujimoto Toshiki Sawai Yuichi Sato Naoto Kumagai Jun Masuda Shiro Nakamori Masaki Ishida Norikazu Yamada Mashio Nakamura Hajime Sakuma Masaaki Ito Kaoru Dohi

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-18-0083, (Released:2018-05-12)

参考文献数

36

被引用文献数

5

---

Background:The present study was conducted to assess the cardiovascular effects of dipeptidyl peptidase-4 inhibitors (DPP4i) on coronary flow reserve (CFR), left ventricular (LV) function and endothelial function of the peripheral artery by comparison with those of α-glucosidase inhibitors (αGI) in patients with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD).Methods and Results:We randomly assigned 30 patients with T2DM and CAD to receive either sitagliptin or voglibose, and 28 patients (age 69±9 years, 75% male, hemoglobin A1c [HbA1c] 6.62±0.48%) completed the study (14 in each group). CFR and LV function, assessed by cardiac magnetic resonance imaging, and endothelial function, assessed by reactive hyperemia peripheral arterial tonometry (RH-PAT), were measured at baseline and 24 weeks after treatment. Clinical and laboratory parameters, including HbA1c level, plasma active glucagon-like peptide-1 concentrations, and biomarkers of inflammation, were unchanged in both groups after 24 weeks of treatment. CFR were unchanged in both the αGI group (3.01±0.98 at baseline and 3.06±0.8 after treatment, P=NS) and the DPP4i group (4.29±2.04 at baseline and 3.63±1.31 after treatment, P=NS), with no interaction effect. LV functional parameters and the reactive hyperemia index also remained unchanged after the 24-week treatment.Conclusions:DPP4i did not improve CFR, LV function or endothelial function of the peripheral artery in patients with relatively well-controlled T2DM and CAD.