A Novel iRFP-Incorporated in vivo Murine Atherosclerosis Imaging System

By using near-infrared fluorescent protein (iRFP)-expressing hematopoietic cells, we established a novel, quantitative, in vivo, noninvasive atherosclerosis imaging system. This murine atherosclerosis imaging approach targets macrophages expressing iRFP in plaques. Low-density lipoprotein receptor-deficient (LDLR−/−) mice transplanted with beta-actin promoter-derived iRFP transgenic (TG) mouse bone marrow (BM) cells (iRFP → LDLR−/−) were used. Atherosclerosis was induced by a nonfluorescent 1.25% cholesterol diet (HCD). Atherosclerosis was compared among the three differently induced mouse groups. iRFP → LDLR−/− mice fed a normal diet (ND) and LDLR−/− mice transplanted with wild-type (WT) BM cells were used as controls. The in vivo imaging system (IVIS) detected an enhanced iRFP signal in the thoracic aorta of HCD-fed iRFP → LDLR−/− mice, whereas iRFP signals were not observed in the control mice. Time-course imaging showed a gradual increase in the signal area, which was correlated with atherosclerotic plaque progression. Oil red O (ORO) staining of aortas and histological analysis of plaques confirmed that the detected signal was strictly emitted from plaque-positive areas of the aorta. Our new murine atherosclerosis imaging system can noninvasively image atherosclerotic plaques in the aorta and generate longitudinal data, validating the ability of the system to monitor lesion progression

Observation of thermoacoustic shock waves in a resonance tube

This paper reports thermally induced shock waves observed in an acoustic resonance tube. Self-sustained oscillations of a gas column were created by imposing an axial temperature gradient on the short stack of plates installed in the resonance tube filled with air at atmospheric pressure. The tube length and axial position of the stack were examined so as to make the acoustic amplitude of the gas oscillations maximum. The periodic shock wave was observed when the acoustic pressure amplitude reached 8.3 kPa at the fundamental frequency. Measurements of the acoustic intensity show that the energy absorption in the stack region with the temperature gradient tends to prevent the nonlinear excitation of harmonic oscillations, which explains why the shock waves had been unfavorable in the resonance tube thermoacoustic systems

Impact of Pericoronary Adipose Tissue Attenuation on Periprocedural Myocardial Injury in Patients With Chronic Coronary Syndrome

Background Perivascular inflammation contributes to the development of atherosclerosis and microcirculatory dysfunction. Pericoronary adipose tissue (PCAT) attenuation, measured by coronary computed tomography angiography, is a potential indicator of coronary inflammation. However, the relationship between PCAT attenuation, microcirculatory dysfunction, and periprocedural myocardial injury (PMI) remains unclear. Methods and Results Patients with chronic coronary syndrome who underwent coronary computed tomography angiography before percutaneous coronary intervention were retrospectively identified. PCAT attenuation and adverse plaque characteristics were assessed using coronary computed tomography angiography. The extent of microcirculatory dysfunction was evaluated using the angio‐based index of microcirculatory resistance before and after percutaneous coronary intervention. Overall, 125 consecutive patients were included, with 50 experiencing PMI (PMI group) and 75 without PMI (non‐PMI group). Multivariable analysis showed that older age, higher angio‐based index of microcirculatory resistance, presence of adverse plaque characteristics, and higher lesion‐based PCAT attenuation were independently associated with PMI occurrence (odds ratio [OR], 1.07 [95% CI, 1.01–1.13]; P=0.02; OR, 1.06 [95% CI, 1.00–1.12]; P=0.04; OR, 6.62 [95% CI, 2.13–20.6]; P=0.001; and OR, 2.89 [95% CI, 1.63–5.11]; P<0.001, respectively). High PCAT attenuation was correlated with microcirculatory dysfunction before and after percutaneous coronary intervention and its exacerbation during percutaneous coronary intervention. Adding lesion‐based PCAT attenuation to the presence of adverse plaque characteristics improved the discriminatory and reclassification ability in predicting PMI. Conclusions Adding PCAT attenuation at the culprit lesion level to coronary computed tomography angiography‐derived adverse plaque characteristics may provide incremental benefit in identifying patients at risk of PMI. Our results highlight the importance of microcirculatory dysfunction in PMI development, particularly in the presence of lesions with high PCAT attenuation. Registration URL: https://center6.umin.ac.jp/cgi‐open‐bin/ctr/ctr_view.cgi?recptno=R000057722; Unique identifier: UMIN000050662

Seasonal variations in gut microbiota and disease course in patients with inflammatory bowel disease.

Background and aimEnvironmental factors are associated with onset and course of inflammatory bowel disease (IBD). Our previous study by about 1,100 IBD patients revealed half of the patients experienced seasonal exacerbation of disease. We investigated the seasonality of fecal microbiota composition of IBD patients.MethodsFecal samples were consecutively collected in each season from IBD outpatients and healthy controls between November 2015 and April 2019. Participants who were treated with full elemental diet or antibiotics within 6 months or had ostomates were excluded. Bacterial profiles were analyzed by 16S rRNA sequencing, and the changes between the diseases and seasons were compared.ResultsA total of 188 fecal samples were analyzed from 47 participants comprising 19 Crohn's disease (CD) patients, 20 ulcerative colitis (UC) patients, and 8 healthy controls (HC). In CD patients, the phylum Actinobacteria and TM7 were both significantly more abundant in autumn than in spring and winter, but not in UC patients and HC. Moreover, the genera Actinomyces, a member of Actinobacteria, and c_TM7-3;o_;f_;g_ (TM7-3), that of TM7, were significantly more abundant in autumn than in spring, and the abundance of Actinomyces was significantly correlated with that of TM7-3 throughout the year in CD patients, but not in UC patients and HC. CD patients with high abundance of TM7-3 in the autumn required significantly fewer therapeutic intervention than those without seasonal fluctuation.ConclusionsOral commensals Actinomyces and its symbiont TM7-3 were correlatively fluctuated in the feces of CD patients by season, which could affect the disease course

Shannon indices in the IBD patients and HCs.

The vertical axis shows the Shannon index for each season, and the horizontal axis shows the season. Bonferroni correction was performed with a paired test for correspondence. No significant difference was found. (TIF)</p

S2 Fig -

(A) Comparison of relative abundances at the phylum level in the four seasons between the IBD patients and HCs. The vertical axis shows the relative abundance, and the horizontal axis indicates each disease. The p value indicates statistical significance according to Tukey’s HSD test *: p B) Seasonal changes at the phylum level in the HCs. The eight main phyla with the largest proportions were examined. Phyla are listed in alphabetical order. There was no significant seasonal variation in any of the phyla. Bonferroni correction was performed with a paired test for correspondence, and a p value less than 0.0083 was considered significant. (TIF)</p

Seasonal changes in disease activity in CD patients.

The vertical axis shows C-reactive protein (CRP) (A) and CDAI (B), and the horizontal axis shows the season (*Sp: Spring, Su: Summer, Au: Autumn, Wi: Winter). Bonferroni correction was performed with a paired test for correspondence, and a p value of less than 0.0083 was considered significant. (TIF)</p

Comparison of the target bacteria in the four seasons among disease groups at the genus level.

The vertical axis shows the relative abundance, and the horizontal axis indicates each disease group. Bacteria belonging to the phyla Actinobacteria and TM7 (genus level) showed seasonal variations in IBD patients. The p value indicates statistical significance according to Tukey’s HSD test. * indicates p (TIF)</p