The novel heart-specific RING finger protein 207 is involved in energy metabolism in cardiomyocytes

A failing heart shows severe energy insufficiency, and it is presumed that this energy shortage plays a critical role in the development of cardiac dysfunction. However, little is known about the mechanisms that cause energy metabolic alterations in the failing heart. Here, we show that the novel RING-finger protein 207 (RNF207), which is specifically expressed in the heart, plays a role in cardiac energy metabolism. Depletion of RNF207 in neonatal rat cardiomyocytes (NRCs) leads to a reduced cellular concentration of adenosine triphosphate (ATP) and mitochondrial dysfunction. Consistent with this result, we observed here that the expression of RNF207 was significantly reduced in mice with common cardiac diseases including heart failure. Intriguingly, proteomic approaches revealed that RNF207 interacts with the voltage-dependent anion channel (VDAC), which is considered to be a key regulator of mitochondria function, as an RNF207-interacting protein. Our findings indicate that RNF207 is involved in ATP production by cardiomyocytes, suggesting that RNF207 plays an important role in the development of heart failure

〈Case Reports〉 A case of abdominal wall abscess caused by fish bone strayed into umbilical hernia

[Abstract] A woman who was 70’s in age was hospitalized with a slow-growing abdominal mass for about one month. An abdominal CT scan showed 35 mm diameter abscess formation under the rectus abdominis muscle, and about 20 mm length high density linear shadow was identified within the abscess. Because she had mild abdominal tenderness, she was followed for a week. A week later, the abscess enlarged to 52 mm in size and an emergency laparotomy was performed. Intestinal perforation was not detected after removal of the fish bone, and abscess drainage was performed. She was discharged from the hospital on the 30th postoperative day without any postoperative complications. In cases of fish bone penetration with abdominal pain, it is important to determine treatment strategy according to abdominal symptoms and CT findings

Realization of the Table Tennis task based on Virtual Targets

This paper describes how a table tennis robot with a fiat paddle coordinates its movement in order to achieve efficient strokes for any given ball. We pro-pose a method of generating stroke movement based on virtual targets that means the point at which the ball should be struck and the paddle velocity just be-fore hitting the ball. These targets are predicted us-ing inputs-outputs maps implemented efficiently by means of a k-d tree (k dimensional tree). The paddle approaches these targets by using a visual feedback control scheme similar to the mirror law proposed by Koditschek. The results of the implementation are also given to show the effectiveness of the proposed method

AST-120 ameliorates lowered exercise capacity and mitochondrial biogenesis in the skeletal muscle from mice with chronic kidney disease via reducing oxidative stress

Background. Exercise capacity and quality of life are markedly impaired in chronic kidney disease (CKD). Increased plasma uremic toxins such as indoxyl sulfate (IS), which induce oxidative stress, may be involved in this process. An oral adsorbent, AST-120, can reduce circulating IS, however, its effects on skeletal muscle and exercise capacity have not been investigated in CKD. Methods. Subtotal-nephrectomy or sham operation was performed in 8-week-old C57BL/6J mice. They were divided into two groups with or without 8% (w/w) of AST-120 in standard diet for 20 weeks. Sham, Sham + AST-120, CKD and CKD + AST-120 (n = 12, each group) were studied. We also conducted a C2C12 cell culture study to determine the direct effects of IS on oxidative stress. Results. Plasma IS levels were significantly increased in CKD compared with Sham (1.05 +/- 0.11 versus 0.21 +/- 0.03 mg/dL, P < 0.05), which was significantly ameliorated in CKD + AST120 (0.41 +/- 0.06 mg/dL). The running distance to exhaustion determined by treadmill tests was significantly reduced in CKD compared with Sham (267 +/- 17 versus 427 +/- 36 m, P < 0.05), and this reduction was also significantly ameliorated in CKD + AST-120 (407 +/- 38 m) without altering skeletal muscle weight. Citrate synthase activity and mitochondrial biogenesis gene were downregulated, and superoxide production was significantly increased in the skeletal muscle from CKD, and these changes were normalized in CKD + AST-120. Incubation of C2C12 cells with IS significantly increased NAD(P) H oxidase activity. Conclusions. The administration of AST-120 improved exercise capacity and mitochondrial biogenesis of skeletal muscle via reducing oxidative stress. AST-120 may be a novel therapeutic agent against exercise intolerance in CKD

Direct renin inhibitor ameliorates insulin resistance by improving insulin signaling and oxidative stress in the skeletal muscle from post-infarct heart failure in mice

Insulin resistance can occur as a consequence of heart failure (HF). Activation of the renin-angiotensin system (RAS) may play a crucial role in this phenomenon. We thus investigated the effect of a direct renin inhibitor, aliskiren, on insulin resistance in HF after myocardial infarction (MI). MI and sham operation were performed in male C57BL/6 J mice. The mice were divided into 4 groups and treated with sham-operation (Sham, n=10), sham-operation and aliskiren (Sham+Aliskiren; 10 mg/kg/day, n=10), MI (n=11), or MI and aliskiren (MI+Aliskiren, n=11). After 4 weeks, MI mice showed left ventricular dilation and dysfunction, which were not affected by aliskiren. The percent decrease of blood glucose after insulin load was significantly smaller in MI than in Sham (14±5% vs. 36±2%), and was ameliorated in MI+Aliskiren (34±5%) mice. Insulin-stimulated serine-phosphorylation of Akt and glucose transporter 4 translocation were decreased in the skeletal muscle of MI compared to Sham by 57% and 69%, and both changes were ameliorated in the MI+Aliskiren group (91% and 94%). Aliskiren administration in MI mice significantly inhibited plasma renin activity and angiotensin II (Ang II) levels. Moreover, (pro)renin receptor expression and local Ang II production were upregulated in skeletal muscle from MI and were attenuated in MI+Aliskiren mice, in tandem with a decrease in superoxide production and NAD(P)H oxidase activities. In conclusion, aliskiren ameliorated insulin resistance in HF by improving insulin signaling in the skeletal muscle, at least partly by inhibiting systemic and (pro)renin receptor-mediated local RAS activation, and subsequent NAD(P)H oxidase-induced oxidative stress

Interaction between terrestrial plasma sheet electrons and the lunar surface: SELENE (Kaguya) observations

Analysis of the data obtained by SELENE (Kaguya) revealed a partial loss in the electron velocity distribution function due to the "gyro-loss effect", namely gyrating electrons being absorbed by the lunar surface. The Moon enters the Earth's magnetosphere for a few days around full moon, where plasma conditions are significantly different from those in the solar wind. When the magnetic field is locally parallel to the lunar surface, relatively high-energy electrons in the terrestrial plasma sheet with Larmor radii greater than SELENE's orbital height strike the lunar surface and are absorbed before they can be detected. This phenomenon can be observed as an empty region in the electron distribution function, which is initially isotropic in the plasma sheet, resulting in a non-gyrotropic distribution. We observed the expected characteristic electron distributions, as well as an empty region that was consistent with the presence of a relatively strong electric field (∼10 mV/m) around the Moon when it is in the plasma sheet