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A 56-year-old female was admitted to our hospital because of respiratory symptoms. Her admission ECG showed normal sinus rhythm and standard echocardiographic evaluation showed no structural or functional abnormalities. She was diagnosed as having sarcoidosis by imaging modalities and mediastinum lymph node biopsy. In this case, 2-dimensional speckle-tracking echocardiography (STE) demonstrated abnormal regional myocardial function and delayed enhancement cardiac magnetic resonance imaging revealed a high intensity area in the same segments. This case suggests that STE is potentially useful for the detection of cardiac sarcoidosis in the early phase.  相似文献   
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Age-related cardiac disease model of Drosophila   总被引:4,自引:0,他引:4  
We have begun to study the genetic basis of deterioration of cardiac function in the fruit fly Drosophila melanogaster as an age-related cardiac disease model. For this purpose we have developed heart function assays in Drosophila and found that the fly's cardiac performance, as that of the human heart, deteriorates with age: aging fruit flies exhibit a progressive increase in electrical pacing-induced heart failure as well as in arrhythmias. The insulin receptor and associated pathways have a dramatic and heart-autonomous influence on age-related cardiac performance in flies, suggestive of potentially similar mechanisms in regulating cardiac aging in vertebrates. Compromised KCNQ and K(ATP) ion channel functions also seem to contribute to the decline in heart performance in aging flies, suggesting that the corresponding vertebrate gene functions may similarly decline with age, in addition to their conserved role in protecting against arrhythmias and hypoxia/ischemia, respectively. The fly heart is thus emerging as a promising genetic model for studying the age-dependent decline in organ function.  相似文献   
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Diamond-like carbon (DLC) films have attracted considerable interest for application as protective films in diverse industrial parts. This is attributed to their desirable characteristics, such as high hardness, low coefficient of friction, gas-barrier properties, and corrosion resistance. Antiseizure properties, in addition to wear resistance, are required during the die molding of polymer and polymer-matrix composite parts. Graphite films can be easily peeled because the vertically stacked graphene sheets are bonded via weak van der Waals forces. The present study demonstrates the fabrication of multilayered DLC/Cu films, where the Cu film functions as a catalyst for the formation of a graphite-like layer between the DLC and Cu films. The DLC/Cu film was synthesized on a Si (100) substrate via plasma-enhanced chemical vapor deposition and magnetron sputtering. The peelability, wear resistance, microstructure, texture, and cross-section of the film were experimentally analyzed. The results indicated a variation in the peelability with the deposition conditions of the Cu film that comprised particles with diameters of several nanometers. The DLC film at the interface in contact with the Cu film was transformed into a graphite-like state i.e., graphitized. The surface of the multilayered film exhibited antiseizure properties with the peeling of the upper DLC film. The multilayered film also exhibited wear resistance owing to the repeated appearances of a new DLC film. It is expected that the wear-resistant films with antiseizure properties demonstrated in the present study will be utilized in various industrial sectors.  相似文献   
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BACKGROUND: Takotsubo cardiomyopathy is triggered by emotional or physical stress especially in post-menopausal women. A reduction in estrogen levels following menopause might underlie the high incidence of takotsubo cardiomyopathy. METHODS AND RESULTS: The left ventricular contraction between ovariectomized rats (OVX) and OVX with estrogen supplementation (OVX + E) while subjected to immobilization stress (IMO) was compared. The IMO in combination with general anesthesia impaired the left ventricular contraction in both OVX and OVX + E. Estrogen supplementation tended to improve the IMO-induced cardiac dysfunction and significantly attenuated the increase of blood pressure and heart rate. To understand the protective mechanism of estrogen, the expression of c-fos mRNA, a marker of cellular activation was compared. The mRNA expression of cardioprotective substances in the heart was also investigated. In the OVX + E, the levels of c-fos mRNA were significantly decreased in the paraventricular hypothalamic nucleus, adrenal gland and left ventricle, suggesting that an increase of estrogen attenuates the emotional stress-induced hypothalamo-sympatho-adrenal outflow from the central nervous system to the target organs. An expression of heat shock protein 70 and atrial natriuretic peptide was significantly augmented in the OVX + E. CONCLUSIONS: These data suggest that estrogen supplementation partially prevents emotional stress-induced cardiovascular responses both by indirect action on the nervous system and by direct action on the heart.  相似文献   
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Secretory phospholipase A2s (sPLA2s) contribute to the hydrolysis of phospholipid. Among them, sPLA2-IIA, -V, and -X have been regarded as enhancers of lipid accumulation in arterial intima. However, the distribution and production of the other types of sPLA2 in human aortic wall remain unclear. Therefore, in this study, the distribution and production of seven types of sPLA2 including IIA, IID, IIE, IIF, III, V, and X in atherosclerosis development in the human aorta were comprehensively examined by immunohistochemistry and in situ hybridization (ISH). The extent of sPLA2s expression increased with atherosclerosis development, but only sPLA2-IIF was never observed in the normal aorta. Double-immunostaining demonstrated that sPLA2-V expression was limited to smooth muscle cells (SMCs), although the other sPLA2s were expressed in both macrophages and SMCs. ISH using sPLA2 cDNAs revealed that the expression pattern of each mRNA was consistent with the results of immunohistochemistry for each corresponding sPLA2. These results indicate that the seven types of sPLA2 are expressed with various patterns in all stages of atherosclerosis development and may play an atherogenic role through degradation of phospholipid.  相似文献   
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We report a female patient who presented with intractable epileptic seizures, profound developmental delay since early infancy, and hyperkinetic movements with hand stereotypies. The patient initially developed focal seizures with multiple foci at 3 months of age. Thereafter, the seizures evolved to frequent episodes of hyperthermia‐induced status epilepticus. A novel de novo SCN1A mutation was identified by whole‐exome sequence analysis. This case demonstrates that SCN1A mutations may cause movement disorders as an atypical phenotype and the case history of this patient may expand our understanding of the clinical spectrum of SCN1A‐associated epileptic encephalopathy. [Published with video sequences]  相似文献   
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[Purpose] To investigate the effects of incorporating elliptical trainer exercise in early rehabilitation after total hip arthroplasty on physical function and self-reported outcomes. [Participants and Methods] Participants with independent gait prior to total hip arthroplasty underwent conventional postoperative physiotherapy and were divided into two groups. The intervention group additionally underwent elliptical trainer exercise, while the control group underwent a walking program. The main outcomes were low back and hip region pain, lower limb muscle strength, single-leg stance time, Timed Up & Go Test results, 10 m walking test results, hip disability and osteoarthritis outcome score, and modified fall efficacy scale score. These outcomes were evaluated preoperatively, at discharge, and at 1 and 3 months postoperatively. [Results] Fifty participants (including 40 females; age, 68.3 ± 10.8 years) participated in this study. Physical function evaluations showed a significant improvement in hip region pain during walking at discharge. Knee extensor strength, single-leg stance time, stride length, and walking speed were significantly greater in the intervention group at discharge and at 1 and 3 months postoperatively. The modified fall efficacy scale score significantly improved in the intervention group 1 month postoperatively. [Conclusion] Elliptical trainer exercise and conventional physiotherapy in the early postoperative period contribute to improved physical function and walking ability and improvement in the fear of falling.  相似文献   
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