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Kazuya Horiuchi, Keita Kasahara, Yusuke Kuroda, Haruna Morohoshi, Yosuke Hagiwara, Gen Ishii Respiratory Disease Center, Showa University Northern Yokohama Hospital, Yokohama-shi, Kanagawa-ken, Japan Purpose: A combination therapy with inhaled corticosteroid (ICS) and a long-acting β agonist (LABA) is the standard treatment for asthmatic patients, and step-down treatment is recommended once control has been achieved. However, little data exist that evaluate the long-term outcomes after step-down treatment. Objective: To compare the long-term outcomes of step-down therapy with ICS/LABA or ICS alone for asthmatic patients who have achieved well-controlled asthma by the ICS (250 µg fluticasone)/LABA (50 µg salmeterol) combination (SFC, two puffs per day). Patients and methods: We randomized 40 well-controlled patients with asthma receiving SFC (250 µg) to two groups; one group of patients received step-down therapy with low-dose SFC (100 µg, two puffs daily) and another group of patients received step-down therapy with high-dose fluticasone propionate (FP) alone (500 µg, daily). The two groups were monitored over 12 months for changes in asthma control test scores, respiratory function (percent forced expiratory volume in 1 second, maximal expiratory flow rate at 50% of the vital capacity [%FEF50], and maximal expiratory flow rate at 25% of the vital capacity [%FEF25]), and the concentration of fractional exhaled nitric oxide. Results: There was no significant difference in the dropout rate between the SFC and FP groups. Low-dose SFC maintained the stability of all parameters over 12 months, whereas the FP group exhibited a rapid 5% decrease in forced expiratory volume in 1 second within 2 months after discontinuation of salmeterol; furthermore, after 10 months, there was a gradual decrease in %FEF50 and %FEF25. Conclusion: This study suggests that a balanced step-down protocol, including both ICS and LABA, is essential in providing long-term stability to patients with mild-to-moderate well-controlled asthma. Keywords: long-term outcome, asthma, fluticasone propionate, salmeterol, step down

Although intravascular ultrasound (IVUS) is used for evaluation of plaque volume and lumen size as well as detection of vessel wall structures after catheter-based interventions, differentiation between the lumen and plaque structures can be difficult. This study attempted to evaluate the efficacy of negative contrast IVUS imaging for assessment of vessel wall morphology after coronary interventions. IVUS studies were performed in 67 lesions in 66 patients before and after coronary interventions. After the baseline ultrasound imaging run, warm 5% glucose solution was injected manually through the guiding catheter into the coronary artery to washout blood from the lumen to avoid speckled reflections from red blood cells (negative contrast). Quantitative measurements were obtained and plaque morphology was assessed for the presence and extent of medial dissections and intimal flaps. There was no difference in each quantitative parameter between baseline images and negative contrast images. The vessel wall boundary was clearly delineated from the lumen, which was defined as effective negative contrast in 51 of 67 lesions (76%). The baseline images revealed plaque dissection in 9 lesions (18%) and an intimal flap in 13 lesions (25%). In addition, 4 dissections (8%) and 16 intimal flaps (31%) were visualized during the infusion of negative contrast. Additional treatment was performed in 4 lesions (8%) based on the images with negative contrast. Negative contrast IVUS was more sensitive in demonstrating a plaque fracture than were baseline images. This method is useful for enhancing the diagnostic capability of IVUS imaging and may influence the decision-making process during interventional procedures.

Late coronary aneurysm formation was observed following treatment by directional coronary atherectomy. Intravascular ultrasound disclosed that the mechanism involved was plaque rupture. The cause of coronary aneurysm may be multifactorial after coronary interventions. Intravascular ultrasound imaging is useful for understanding the pathologic mechanism of coronary aneurysm production.

Cosmogenic nuclides in tree rings and polar ice cores record the information of past cosmic ray intensities and solar activities. A large 14C increase over 10 years has been discovered around 5480 BCE. The 14C variations in this event differ from those of other short‐term cosmic ray events and typical grand solar minima. To elucidate the cause of the 14C increase around 5480 BCE, we measured the 10Be and 36Cl concentrations in the Antarctic Dome Fuji ice core at quasi‐annual and 4–5 years resolutions, respectively. Based on the combined 14C, 10Be, and 36Cl data, the 5480 BCE event was probably not caused by a solar proton event (SPE) or a gamma‐ray event, because the 36Cl concentration did not significantly increase as expected in these events. The incremented 10Be data were enhanced similarly to those of recent grand solar minima, but more rapidly increased (over ∼10 years). These results suggest that an unusual grand solar minimum occurred around 5480 BCE, characterized by a rapidly decreasing solar activity. Key Points: New high‐resolution 10Be and 36Cl data for the 5480 BCE cosmic ray event were taken from the Antarctic Dome Fuji ice coreMeasured 36Cl/10Be ratio was not suitable for either solar proton event or gamma‐ray event originsThe 5480 BCE event might refer to the unusual grand solar minimum which solar activity decreased rapidly in ∼10 years [ABSTRACT FROM AUTHOR]