Publications by authors named "Ikeyama S"

We studied photoinduced charge transfer (CT) states and their dissociation processes at the donor/acceptor (D/A) interface of PTB7/BTAx (x = 1 and 3) nonfullerene organic thin-film solar cells using density functional theory (DFT) and time-dependent DFT calculations. We focused on the CT distances and electron coupling in the CT state generated by photoexcitation and the Huang-Rhys (HR) factors that describe the nonadiabatic processes associated with vibronic interactions. The PTB7/BTA3 system with a large short-circuit current density (JSC) exhibited a large charge CT distance and electronic coupling.

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Cystinuria is an autosomal recessive disorder characterized by a decrease in the reabsorption of cystine and dibasic amino acids (lysine, ornithine, and arginine) in the renal proximal tubule. It presents with recurrent urolithiasis. Cystinuria accounts for 6-8% of all pediatric urolithiasis.

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The utilization of the light-harvesting and electron-transferring function of chlorophylls (Chls) has received attention for visible-light driven hydrogen production. In this work, a series of Chl derivatives based on pyropheophorbide-a (Pyro-a) conjugated with a viologen moiety, including a Pyro-a methyl ester directly bonded with the viologen at the 3-position 1, its 31-methylene analog 2 and Pyro-a connected with the viologen in the 17-substituent 3, were synthesized from chemical modification of naturally occurring Chl-a and characterized in terms of their photochemical and photophysical properties. As the photoexcited singlet state of the Pyro-a moiety was strongly quenched by the viologen moiety in a molecule, the effective photoinduced intramolecular electron transfer from Pyro-a to the bonded viologen moiety occurred.

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Background: Gastric hematoma is a rare disorder. Here we report a case of a large gastric intramural hematoma mimicking an impending rupture of a visceral artery aneurysm.

Case Presentation: A 60-year-old Japanese woman complained of left flank pain.

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The effect of the functional ionic group of 4,4'-bipyridinium salt derivatives (4,4'-BPs) as the electron carrier on the visible-light driven conversion of CO to formic acid with the system consisting of water-soluble zinc tetraphenylporphyrin tetrasulfonate (ZnTPPS) and formate dehydrogenase (FDH) in the presence of triethanolamine (TEOA) as an electron donor was investigated. 1,1'-Diaminoethyl- (DAV), 1-aminoethyl-1'-methyl- (AMV), 1-carboxymethyl-1'-methyl- (CMV) and 1,1'-dicarboxymethyl-4,4'-bipyridinium salt (DCV) were prepared as the 4,4'-BPs with the functional ionic group. Irradiation of a CO saturated buffer solution containing TEOA, ZnTPPS, 4,4'-BP and FDH with visible light irradiation resulted in the production of formic acid.

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Recently, CO utilization technology, including artificial photosynthesis, has received much attention. In this field, CO is used as a feedstock for fuels, polymers and in other chemical processes. Of note are malic enzymes (MEs) which catalyze the reaction of malic acid to pyruvic acid and CO with the co-enzyme NADP, and catalyze the reverse reaction of pyruvic acid and CO to malic acid with the co-enzyme NADPH.

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Purposes: Pancreatoduodenectomy (PD) was performed for 6 periampullary cancer patients by using methods verified by quality randomized controlled trials (RCT) in a low-volume center (LVC). The purpose of this study was to verify the clinical results.

Methods: No-touch pylorus-resecting pancreatoduodenectomy (PrPD), antecolic gastrojejunostomy, pancreatico-jejunostomy with a lost stent tube to the main pancreatic duct, and early removal of a prophylactic drain were performed.

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A 74-year-old male with abdominal pain was admitted to the emergency room in our hospital. The high value of serum amylase was shown in his blood test. The postcontrast computed tomography (CT) showed the huge retroperitoneal tumor with a thin-walled mass occupying most of the part of the right retroperitoneal space.

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Abdominal wall hematoma is a rare and life-threatening complication after carotid artery stenting (CAS), but it can occur when activated clotting time is prolonged. We report a right lateral abdominal wall hematoma caused by rupture of the superficial circumflex iliac artery after CAS in a 72-year-old man with severe stenosis of the origin of the right internal carotid artery. We performed CAS for the targeted lesion while activated clotting time exceeded 300 seconds.

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The study investigated the possibility of pharmacologically modulating hepatic allograft function from non-heart-beating donors (NHBDs) using male Lewis rats. The donors were divided into 4 groups: Group 1 in which the vehicle was administered, Group 2 in which FK506 (tacrolimus; a powerful immunosuppressive agent) was administered, Group 3 in which OKY046 (a specific thromboxane synthetase inhibitor) was administered and Group 4 in which FK506 and OKY046 were administered. The recipients received orthotopic liver transplantation.

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Background/aims: Preoperative right portal vein embolization enhances remnant liver function following massive hepatectomy. Several studies have reported an increase in the volume of the left hepatic lobe after right portal vein embolization, but little information exists regarding heat shock protein induction in hepatocytes after right portal vein embolization. The objective of this study is to determine whether heat shock protein is induced in hepatocytes after right portal vein embolization in patients who underwent extended right hepatic lobectomy.

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It is well established that the proliferative potential of the liver declines with aging. Epidermal growth factor (EGF)-stimulated DNA synthesis is reduced in hepatocytes from aged rats relative to young rats, and this reduction correlates with diminished activation of the extracellular signal-regulated kinase (ERK) pathway and lower phosphorylation of the EGF receptor on residue Y1173. Calorie restriction (CR) can increase rodent life span and retard many age-associated declines in physiologic function, but its influence on cell proliferation is unknown.

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Aging is generally accompanied by reduced tolerance to oxidative stress and altered responsiveness to proliferative signals. We have shown that hepatocytes derived from aged rats (24-26 months) exhibit greater sensitivity to H(2)O(2) treatment and reduced proliferation following epidermal growth factor (EGF) treatment than cells of young adult rats (5-6 months). Here we examined the effects of aging and calorie restriction (CR) on expression of the oxidative stress-inducible and pro-apoptotic gene gadd153 (chop) in these hepatocytes, and we investigated its influence on sensitivity to oxidants.

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Accumulation of oxidative damage is believed to be a major contributor to the decline in physiologic function that characterizes mammalian aging, and recent studies suggest that how well you respond to acute oxidative stress is an important factor in determining longevity. Oxidant injury elicits a wide spectrum of responses ranging from proliferation to cell death. The particular outcome observed largely reflects the severity of the stress encountered and the relative degree of activation of various signal transduction pathways aimed at enhancing survival or inducing cell death.

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Oxidative stress is believed to be an important factor in the development of age-related diseases, and studies in lower organisms have established links between oxidative stress tolerance and longevity. We have hypothesized that aging is associated with a reduced ability to mount acute host defenses to oxidant injury, which increases the vulnerability of aged cells to stress. We tested this hypothesis by using primary hepatocytes from young (4-6 months) and aged (24-26 months) rats.

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Background/aims: A stress-inducible heat shock protein 70 (HSP70) is one of the best-known endogenous factors protecting cell injury under various pathological conditions. The aim of this study was to examine anti-apoptotic actions of a non-toxic HSP70 inducer, geranylgeranylacetone (GGA), on hepatocytes exposed to hydrogen peroxide (H2O2) or ethanol.

Methods: Primary cultures of rat hepatocytes were treated with different concentrations of GGA and exposed to 0.

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We report new surgical techniques for intraoperative microwave coagulation therapy (IMCT), conducted in three patients with large liver neoplasms with poor liver function or difficult tumor location. Anterolateral thoracotomy was performed for tumors in the right lobe to obtain a good operative field. Four electrode needles were inserted for microwave irradiation, with settings of 60 W, 45 s for coagulation and 1 s for dissociation.

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To investigate the role of apoptosis in the pathogenesis of rat chronic progressive nephrosis (CPN), the kidney of male F344/DuCrj rats, 19, 59, and 111 weeks of age, was examined histologically. In situ analysis for DNA fragmentation and proliferating cell nuclear antigen (PCNA) was performed simultaneously by TdT-mediated dUTP-biotin nick end labeling (TUNEL) and immunohistochemistry, respectively. CPN was seen in all the kidneys of 59-week-old (n=6) and 111-week-old rats (n=16), correlating significantly (p<0.

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To examine the effect on cell population in hepatocytes of phenobarbital (PB) and other barbiturates, PB, allobarbital (ALB), barbital sodium (BS) and barbituric acid (BA) were given orally to male rats for 7 consecutive days. Although there was no apparent change in non-promoting BA, hepatomegaly was induced by PB, BS and ALB, which are promoters of hepatocarcinogenesis. In PB- and BS-treated livers, hepatomegaly was attributable to hepatocyte proliferation and enzyme induction.

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A pinealoma (benign) was found in a 61-week-old male Crj:CD (SD) IGS rat. The neoplasm was located between the cerebral hemispheres and the cerebellum. Histologically, the tumor cells consisted of two cell types: large, pale-staining cells and small dark-staining cells.

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A 43-year-old woman was admitted to our hospital for sigmoid colon cancer with multiple liver metastasis (H3). As preoperative CTAP (CT during arterial portography) examination showed 23 metastatic nodules in the whole liver, hepatic resections were not indicated. Angiographic findings showed that right and left hepatic arteries branched separately from the celiac artery.

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The effects of TNP-470 on DNA synthesis and the expression of c-myc and cyclin D1 mRNAs were investigated in human umbilical vein endothelial (HUVE) cells synchronized by serum depletion and stimulated with bFGF and serum. DNA synthesis occurring 16 h after stimulation was inhibited when TNP-470 was present from 2 to 6 h after stimulation. C-myc mRNA expression occurring 2 h after stimulation was not inhibited by the addition of TNP-470.

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The angiogenesis inhibitor O-(chloroacetyl-carbamoyl)fumagillol (TNP-470) showed antitumor activity in three human cancer xenograft systems. TNP-470 potently inhibited the tumor growth of hormone-independent prostate cancer PC-3 cells and breast cancer MDA-MB-231 cells dose dependently at weekly s.c.

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The effect of the potent angiogenesis inhibitor O-(chloroacetyl-carbamoyl)fumagillol (TNP-470), a semisynthetic analogue of fumagillin, on tumor growth and metastasis was studied using rodent tumors. Injection of TNP-470 s.c.

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Previously we showed that motility-related protein (MRP-1) is an antigen recognized by monoclonal antibody (mAb) M31-15 inhibiting cell motility and that the sequence of MRP-1 coincides with that of CD9. In the present study, plasmid was constructed in which human MRP-1/CD9 cDNA is expressed under the control of the Abelson murine leukemia virus promoter sequence. The expression plasmid for MRP-1/CD9 was introduced into Chinese hamster ovary cells, human lung adenocarcinoma cell line MAC10 (MRP-1 positive), and human myeloma cell line ARH77 (MRP-1 negative).

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