著者

Hiroyuki Tsutsui Shin-ichi Momomura Akira Yamashina Hiroaki Shimokawa Yasuki Kihara Yoshihiko Saito Nobuhisa Hagiwara Hiroshi Ito Masafumi Yano Kazuhiro Yamamoto Junya Ako Takayuki Inomata Yasushi Sakata Takashi Tanaka Yasushi Kawasaki on behalf of the J-SHIFT Study Investigators

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-19-0227, (Released:2019-08-08)

参考文献数

18

被引用文献数

24 49

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Background:Increased heart rate (HR) is an independent risk factor for cardiovascular outcomes in chronic heart failure (HF). Ivabradine, anIfinhibitor, improved outcomes in patients with HF and reduced ejection fraction (HFrEF) in the SHIFT study. We evaluated its efficacy and safety in Japanese HFrEF patients in a randomized, double-blind, placebo-controlled phase III study: the J-SHIFT study. The main objective was to confirm a hazard ratio of <1 in the primary composite endpoint of cardiovascular death or hospital admission for worsening HF.Methods and Results:Patients with NYHA functional class II–IV, left ventricular EF ≤35%, and resting HR ≥75 beats/min in sinus rhythm under optimal medical therapy received ivabradine (n=127) or placebo (n=127). Mean reduction in resting HR was significantly greater in the ivabradine group (15.2 vs. 6.1 beats/min, P<0.0001). However, symptomatic bradycardia did not occur. A total of 26 (20.5%) patients in the ivabradine group and 37 (29.1%) patients in the placebo group had the primary endpoint event (hazard ratio 0.67, 95% CI 0.40–1.11, P=0.1179) during median follow-up of 589 days. Mild phosphenes were reported in 8 (6.3%) patients in the ivabradine group and 4 (3.1%) patients in the placebo group (P=0.3760).Conclusions:The J-SHIFT study supported the efficacy and safety of ivabradine for Japanese HFrEF patients, in accord with the SHIFT study.

著者

Hiroyuki Tsutsui Tomomi Ide Yasushi Kawasaki

出版者

The Japanese Circulation Society

雑誌

Circulation Journal (ISSN:13469843)

巻号頁・発行日

pp.CJ-20-0590, (Released:2020-07-31)

参考文献数

7

被引用文献数

2

著者

Yasushi Kawasaki Yuki Yoneda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-R004, (Released:2019-04-05)

被引用文献数

24

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Uniform temperature throughout a greenhouse is recommended, as the present climate control method and many other studies have shown that the temperature gradient decreases vertically and horizontally in a greenhouse. However, recent research revealed that roots, fruits, flowers, and shoot-tips are more sensitive to temperature changes than leaves and stems, indicating that uniform temperature control may not be necessary. In addition, energy-saving techniques that do not lead to yield loss are desirable to reduce energy costs and ensure sustainable greenhouse production. In this paper, we review current studies on local temperature control methods in greenhouse vegetable production, primarily focusing on the tomato, and compare them with novel climate-control techniques. Roots, fruits, shoot-tips and flowers are sensitive to temperature changes, showing negative symptoms under extreme temperature conditions. Therefore, the temperature of these plant organs should be controlled locally. Root zone temperature control enhances root growth and its associated physiological activities, promoting uptake of water and mineral nutrients. This subsequently leads to enhanced growth of shoots. Fruit temperature control may not be effective for tomato plants, but it promotes fruit growth and fruit sugar accumulation in melons and watermelons. Shoot-tip temperature control promotes the differentiation of leaf and flower buds. Flower temperature control enhances pollen viability and promotes fruit set. The combination of shoot-tip and flower heating enables low energy consumption compared with conventional heating, without loss of yield. Local temperature control techniques (except roots) have been studied in recent years; however, there is a distinct lack of research on the physiological mechanisms and practical approaches to develop a better local temperature control system. Thus, further studies are required on this area in the future.

著者

Yasushi Kawasaki Tadahisa Higashide

出版者

一般社団法人 園芸学会

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.OKD-118, (Released:2017-11-17)

被引用文献数

1

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Fruit growth represents the balance between material influxes via xylem and phloem and efflux by transpiration via the stomata of the calyx and cuticle of fruit, which determines the yield and soluble solids content (SSC). Knowledge of these factors is important for the production of high-SSC tomato fruit, but no physiological indicator is available to allow prediction of fruit yield and SSC for breeding and crop production purposes. To identify indicators, we grew Japanese, Dutch, Japanese × Dutch, and high-SSC cultivars and sought correlations of the fluxes to fruit with yield and SSC. To estimate the contributions of the xylem, phloem, and transpiration fluxes to fruit weight increase, we measured 2-day growth rates of intact, detached, and heat-girdled (peduncle steamed for 90 to 120 s) fruits treated at 14, 28, or 42 days after flowering (DAF). Xylem influx was much lower in the high-SSC cultivar than in the others. Phloem influx was lower in the Dutch and hybrid cultivars at 28 DAF. Transpiration efflux was greater in the Japanese cultivar at 42 DAF. Fruit growth rate at 14 DAF was positively correlated with yield, and phloem influx per fruit weight increase at 14 and 28 DAF was positively correlated with SSC. These results show how the xylem, phloem, and transpiration fluxes of fruit can predict fruit yield and SSC. This information will help the production and breeding of high-SSC fruit.

著者

Yasushi Kawasaki Satoshi Matsuo Yoshinori Kanayama Koki Kanahama

出版者

園芸学会

雑誌

Journal of the Japanese Society for Horticultural Science (ISSN:18823351)

巻号頁・発行日

pp.MI-001, (Released:2014-09-03)

被引用文献数

4 27

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Low-cost heating is needed to reduce chilling injuries, heating costs, and CO2 emission during greenhouse tomato production. To acquire information about the physiological and morphological effects of root-zone heating, an economical option at low air temperatures, we grew tomato plants on a nutrient film technique hydroponic system in a heated nutrient solution. We investigated the effects of short-term root-zone heating after transplanting and long-term heating until harvest. We measured short-term plant growth, nutrient uptake, root activity (xylem exudation and root respiration rates), root indole-3-acetic acid (IAA) concentration, internal root structure, and long-term fruit weight and dry matter distribution. The minimum root-zone temperature was maintained at 16.6°C, while the minimum air temperature (5.9°C) and the minimum root-zone temperature in the control (5.8°C) were lower than optimal. After 7 days of root-zone heating, root dry weight and relative growth rate increased compared with those of the control, accompanied by increased mineral nutrient uptake and xylem exudation. These changes may explain the increased shoot growth after 21 days of heating. In roots, development of the epidermis and stele, including the xylem, was promoted by heating, in contrast to previous research on root-zone cooling at high air temperature, which promoted xylem-specific development. Although the proportion of dry matter distributed to the fruit was not changed by root-zone heating, individual fruit size and total yield were higher than in the control due to a higher total dry weight in the heating treatment. Our results suggest that root-zone heating is an effective low-cost heating technology at low air temperature because of its effects on root activity, growth, and fruit yield, but that the mechanisms may differ from those in root-zone cooling at high air temperature.