50 research outputs found

    Ultrafast isomerization-induced cooperative motions to higher molecular orientation in smectic liquid-crystalline azobenzene molecules

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    The photoisomerization of molecules is widely used to control the structure of soft matter in both natural and synthetic systems. However, the structural dynamics of the molecules during isomerization and their subsequent response are difficult to elucidate due to their complex and ultrafast nature. Herein, we describe the ultrafast formation of higherorientation of liquid-crystalline (LC) azobenzene molecules via linearly polarized ultraviolet light (UV) using ultrafast time-resolved electron diffraction. The ultrafast orientation is caused by the trans-to-cis isomerization of the azobenzene molecules. Our observations are consistent with simplified molecular dynamics calculations that revealed that the molecules are aligned with the laser polarization axis by their cooperative motion after photoisomerization. This insight advances the fundamental chemistry of photoresponsive molecules in soft matter as well as their ultrafast photomechanical applications

    Skeletal myoblast sheet transplantation improves the diastolic function of a pressure-overloaded right heart

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    ObjectiveThe development of right ventricular dysfunction has become a common problem after surgical repair of complex congenital heart disease. A recent study reported that tissue-engineered skeletal myoblast sheet transplantation improves left ventricular function in patients with dilated and ischemic cardiomyopathy. Therefore myoblast sheet transplantation might also improve ventricular performance in a rat model of a pressure-overloaded right ventricle.MethodsSeven-week-old male Lewis rats underwent pulmonary artery banding. Four weeks after pulmonary artery banding, myoblast sheet transplantation to the right ventricle was performed in the myoblast sheet transplantation group (n = 20), whereas a sham operation was performed in the sham group (n = 20).ResultsFour weeks after performing the procedure, a hemodynamic assessment with a pressure–volume loop showed a compensatory increase in systolic function in both groups. However, only the myoblast sheet transplantation group showed a significant improvement in the diastolic function: end-diastolic pressure (sham vs myoblast sheet transplantation, 10.3 ± 3.1 vs 5.0 ± 3.7 mm Hg; P < .001), time constant of isovolumic relaxation (11.1 ± 2.5 vs 7.6 ± 1.2 ms, P < .001), and end-diastolic pressure–volume relationship (16.1 ± 4.5 vs 7.6 ± 2.4/mL, P < .005). The right ventricular weight and cell size similarly increased in both groups. A histologic assessment demonstrated significantly suppressed ventricular fibrosis and increased capillary density in the myoblast sheet transplantation group in comparison with those in the sham group. Reverse transcription–polymerase chain reaction demonstrated an increased myocardial gene expression of hepatocyte growth factor and vascular endothelial growth factor in the myoblast sheet transplantation group but not in the sham group.ConclusionsSkeletal myoblast sheet transplantation improved the diastolic dysfunction and suppressed ventricular fibrosis with increased capillary density in a rat model of a pressure-overloaded right ventricle. This method might become a novel strategy for the myocardial regeneration of right ventricular failure in patients with congenital heart disease

    The administration of high-mobility group box 1 fragment prevents deterioration of cardiac performance by enhancement of bone marrow mesenchymal stem cell homing in the delta-sarcoglycan-deficient hamster.

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    ObjectivesWe hypothesized that systemic administration of high-mobility group box 1 fragment attenuates the progression of myocardial fibrosis and cardiac dysfunction in a hamster model of dilated cardiomyopathy by recruiting bone marrow mesenchymal stem cells thus causing enhancement of a self-regeneration system.MethodsTwenty-week-old J2N-k hamsters, which are δ-sarcoglycan-deficient, were treated with systemic injection of high-mobility group box 1 fragment (HMGB1, n = 15) or phosphate buffered saline (control, n = 11). Echocardiography for left ventricular function, cardiac histology, and molecular biology were analyzed. The life-prolonging effect was assessed separately using the HMGB1 and control groups, in addition to a monthly HMGB1 group which received monthly systemic injections of high-mobility group box 1 fragment, 3 times (HMGB1, n = 11, control, n = 9, monthly HMGB1, n = 9).ResultsThe HMGB1 group showed improved left ventricular ejection fraction, reduced myocardial fibrosis, and increased capillary density. The number of platelet-derived growth factor receptor-alpha and CD106 positive mesenchymal stem cells detected in the myocardium was significantly increased, and intra-myocardial expression of tumor necrosis factor α stimulating gene 6, hepatic growth factor, and vascular endothelial growth factor were significantly upregulated after high-mobility group box 1 fragment administration. Improved survival was observed in the monthly HMGB1 group compared with the control group.ConclusionsSystemic high-mobility group box 1 fragment administration attenuates the progression of left ventricular remodeling in a hamster model of dilated cardiomyopathy by enhanced homing of bone marrow mesenchymal stem cells into damaged myocardium, suggesting that high-mobility group box 1 fragment could be a new treatment for dilated cardiomyopathy

    Effectiveness and adverse effects of radical radiotherapy on patients aged 90 or above.

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    Purpose: In recent years, there were reports that adults and elderly individuals exhibit similar rates of tumor control, treatment success, and side effects. We aim to evaluate the effects of radical radiation therapy on people aged 90 years or above.Materials and Methods: Radiotherapy for radical cure purposes was administered on 25 patients. A dose of 60 Gy/30 fraction was given to 20 of the 25 patients. The other doses given were 30 Gy/5 fraction to one patient with skin cancer; SBRT at 52 Gy/4 fraction and 48 Gy/4 fraction, respectively, to two patients with lung cancer; 40 Gy/20 fraction to one patient with plasmacytoma; and 39 Gy/13 fraction to one patient with pancreatic cancer. For the assessment of treatment response, the RECIST. Adverse event was estimated on the basis of the CTCAE.Results: All 25 patients were able to finish the treatment. The average age was 93.1, with a larger population of women than that of men. Radiotherapy with curative intent provided complete response + partial response in 24 cases.Conclusion: Among elderly cancer patients aged 90 years or above, particularly those with skin cancer, the response rate was high. No adverse events higher than grade 2 were observed

    Data from: Impact of microRNA expression in human atrial tissue in patients with atrial fibrillation undergoing cardiac surgery

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    Background: Although microRNA (miRNA) regulates initiation and/or progression of atrial fibrillation (AF) in canine AF models, the underlying mechanism in humans remains unclear. We speculated that certain miRNAs in atrial tissue are related to AF, and evaluated the relationship of miRNA expression in human atrial tissue in cardiac surgery patients. Methods: Right atrial tissues from 29 patients undergoing cardiovascular surgery were divided into 3 groups [A: chronic AF or unsuccessful maze, n=6; B: successful maze, n=10; C: sinus rhythm (SR) n=13]. miRNA expression was determined using high density microarrays and with Reverse transcriptase-polymerase chain reaction (RT-PCR). Fibrosis was examined using Masson trichrome staining. Results: miRNA microarray analysis showed elevated miRNA-21, miRNA-23b, miRNA-199b, and miRNA-208b in AF as compared to SR groups. RT-PCR showed elevated miRNA-21 (1.9-fold) and miRNA-208b (4.2-fold) in AF as compared to the SR groups. miRNA-21 expression increased from Group C to A (A: 2.1-fold, B: 1.8-fold, C: 1.0-fold). Fibrosis increased from C to A (A: 43.0±12.9%, B: 21.3±6.1%, C: 11.9±3.1%). Percent fibrosis and miRNA-21 expression were correlated (r=0.508, p<0.05). The plasma levels of miRNA-21 in AF patients was significantly decreased as compared to the healthy volunteers (p<0.05). Conclusion: The expression of miRNA-21 in human atrial tissue was found to be related to atrial fibrosis and might affect AF occurrence, indicating its usefulness as a biomarker for cardiac surgery management
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