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Mouse pancreatic development is critically dependent on epithelial-mesenchymal interactions. The pancreas differs from other epithelial-mesenchymal organs in that the epithelium gives rise to both epithelial exocrine cells and non-epithelial endocrine cells. We studied the nature of the interactions between the epithelium and mesenchyme with respect to the decision between exocrine and endocrine lineages. We show here a tripartite influence of mesenchyme on the developing epithelium. First, close proximity or contact of mesenchyme with the epithelium induces exocrine differentiation. Second, this mesenchymal proximity to the epithelium suppresses endocrine differentiation. Third, mesenchyme has an overall enhancing effect on the degree of insulin differentiation, suggesting a pro-endocrine effect in those epithelial cells at a distance from the mesenchyme. Proximity or contact between the mesenchyme and epithelium appeared to be necessary for the pro-exocrine effects of mesenchyme. We found that, in a co-culture system, NIH3T3 cells were able to substitute for mesenchyme in exocrine induction as well as in both the endocrine induction and endocrine inhibition, implying that the responsible molecules are not unique to pancreatic mesenchyme. Laminin appears to be a key molecule mediating the epithelial-mesenchymal interactions that lead to exocrine differentiation, since inhibition of laminin expression resulted in blockage of the pro-exocrine induction of mesenchyme. Keywords: Epithelial-mesenchymal interactions; Pancreas; Epithelium culture; Endocrine and exocrine differentiation; Laminin; Morpholino antisense oligos; Insulin

• Anorectal malignant melanoma is rare and prone to metastasis. • An anorectal melanoma was resected via transperineal abdominoperineal resection (TpAPR). • The patient remained disease-free until the 24-month follow-up. • TpAPR/total mesorectal excision (TME) for anorectal melanoma appears to be a feasible approach. Anorectal melanoma is a rare type of cancer characterized by frequent metastasis. We report our experience with a case of anorectal melanoma resected via transperineal abdominoperineal resection and total mesorectal excision. A 77-year-old woman visited our hospital with the complaint of melena. Colonoscopic examination revealed a black type 1 tumor measuring 5 mm in size on the dentate line of the anal canal circumference. Tumor biopsy revealed malignant melanoma, and positron emission tomography-computed tomography showed tracer accumulation within the mass but not at other sites. We performed a two-stage abdominoperineal resection surgery with lymphadenectomy via transperineal abdominoperineal resection, and pathological diagnosis indicated submucosal tumor depth. The patient was diagnosed with T2 N0 M0 stage I malignant melanoma and was followed on an outpatient basis. A 24-month follow-up computed tomography revealed multiple liver metastases. Anorectal melanoma is associated with a very poor prognosis because of its association with early lymph node metastasis and distant metastasis. The tumor may spread beyond the main lesion and involve the surrounding mucosa and draining lymph nodes. Transperineal abdominoperineal resection is a minimally invasive procedure that can be used to achieve curative tumor resection with lymphadenectomy. Transperineal abdominoperineal resection appears to be a feasible approach for the treatment of anorectal melanoma. [ABSTRACT FROM AUTHOR]

Highlights • Umbilical zigzag incision was feasible for concomitant surgery. • It could be used for every part of abdominal laparoscopic operations. • The umbilical wound was almost invisible after surgery. Abstract Introduction Recently, use of reduced-port surgery has become widespread; however, it is a difficult operation. Hachisuka et al. developed a method called the umbilical zigzag incision, which enlarges the fascial incision using only an umbilical skin incision. We believe this method will be feasible for concomitant laparoscopic surgery. We report our surgical techniques for concomitant laparoscopic surgery using an umbilical zigzag incision. Methods The patient who should receive more than 2 places of abdominal operation were indicated this procedure. In all cases, we made the zigzag incision in the umbilical region. After the linea alba and peritoneum were incised, the wound retractor was inserted through the incision, which enlarges the fascial opening. GelPoint was attached to the wound retractor and the operation was started. Results We could create a fascial opening of up to 6 cm with the umbilical zigzag incision, which improves the triangulation of forceps and reduces interference among the trocars. The trocars in the center of the abdomen could be utilized for almost all intraperitoneal operations. This procedure was especially useful in cases that included lymph node dissection because dissection of a malignant tumor is a delicate procedure. Furthermore, extraction of specimens and anastomosis went very smoothly because the fascial incision was large enough such that no extension of the incision was needed. No early or late postoperative complications occurred in any case. Postoperative wounds were clear and therefore patient satisfaction levels were high. Conclusion Umbilical zigzag incision may be feasible especially in concomitant laparoscopic surgery. [ABSTRACT FROM AUTHOR]

In the present study, to observe the contact interface during sheet metal forming process, in-situ observation system using transparent silica glass dies and high speed recording camera was developed. To correlate the dimensional parameters of micro-textured structures and tribological properties during the forming operation, in-situ observation during ironing process of stainless steel sheet with a thickness of 0.1 mm was performed. Tribological behavior was compared between the different dimple structures under different contact state. Dimple structure arrays with diameters of 10, 50, 100 µm were achieved by using femto-/pico-second laser processing. As results, the textured die with dimple diameters of 10 and 50 µm showed the lubricant flow transferred from one to the other dimple structures, in which hydrodynamic pressure seems to generate inside the dimples, while that of 100 µm indicated the less supply of lubricant. However, for the textured die with a dimple diameter of 10 µm demonstrated higher ironing force than that of 50 µm, due to the coverage of dimple structures by generated wear debris during the forming process. Based on these experimental findings between different contact states, the principle in generation of hydrodynamic pressure, the function of micro-trap for wear debris and the micro-reservoirs effect for lubricant retention depending on the size of dimple structures were discussed by correlating with the in-situ observation results. [ABSTRACT FROM AUTHOR]

Purpose: Kososan (KSS), a traditional Japanese medicine with a distinct aroma, is clinically used to treat affective disorders but its antidepressant-like effect has not been thoroughly investigated. In this study, we investigated the effects of inhaled and orally administered KSS on sleep disturbances in socially isolated mice.Methods: Four-weeks-old male ddy mice were housed either in social isolation or in groups for 4-6 weeks before the experiment. KSS was orally administered (0.5 or 1.0 g/kg) or inhaled (0.5, 1.0, or 2.5 g/0.125 m(3)) 60 min before pentobarbital administration. Stress levels in mice were evaluated by the duration of pentobarbital-induced sleeping time.Results: Sleeping time was shorter in socially-isolated mice than in group-housed mice. Oral and inhaled KSS prolonged sleeping time in stressed mice, but had no effect on sleeping time of group-housed mice. Prolonged sleeping time after oral KSS was significantly inhibited (p<0.05) by bicuculline (3 mg/kg, i.p.), a GABAA antagonist, but not by flumazenil (3 mg/kg, i.p.), a selective benzodiazepine antagonist. Prolonged sleeping time after KSS inhalation was significantly inhibited (p<0.05) by flumazenil but not by bicuculline.Conclusions: Our findings suggest that KSS activates GABAA-benzodiazepine receptor complex and reverses shortened pentobarbital-induced sleep caused by social isolation. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Kososan (KSS), a traditional Japanese medicine with a distinct aroma, is clinically used to treat affective disorders but its antidepressant-like effect has not been thoroughly investigated. In this study, we investigated the effects of inhaled and orally administered KSS on sleep disturbances in socially isolated mice. Methods: Four-weeks-old male ddy mice were housed either in social isolation or in groups for 4–6 weeks before the experiment. KSS was orally administered (0.5 or 1.0g/kg) or inhaled (0.5, 1.0, or 2.5g/0.125m3) 60min before pentobarbital administration. Stress levels in mice were evaluated by the duration of pentobarbital-induced sleeping time. Results: Sleeping time was shorter in socially-isolated mice than in group-housed mice. Oral and inhaled KSS prolonged sleeping time in stressed mice, but had no effect on sleeping time of group-housed mice. Prolonged sleeping time after oral KSS was significantly inhibited (p <0.05) by bicuculline (3mg/kg, i.p.), a GABAA antagonist, but not by flumazenil (3mg/kg, i.p.), a selective benzodiazepine antagonist. Prolonged sleeping time after KSS inhalation was significantly inhibited (p <0.05) by flumazenil but not by bicuculline. Conclusions: Our findings suggest that KSS activates GABAA-benzodiazepine receptor complex and reverses shortened pentobarbital-induced sleep caused by social isolation. [Copyright &y& Elsevier]

Abstract: This paper summarizes the development of a new numerical simulator for environmental impact assessment of CO2 geological storage and the results of case studies. The simulator is developed by coupling the multiphase fluid flow simulator TOUGH2 and an open-source FEM code FrontISTR. Case studies for In Salah CO2 storage project are conducted to assess the validity of the developed simulator. Then, sensitivity analyses for physical parameters corresponding to pore space and rock rigidity are conducted. Results are consistent with measured data and suggest the validity of the simulator. [Copyright &y& Elsevier]

Abstract: Many different physical characteristics of goldfish (Carassius auratus auratus), such as celestial and telescopic eyes, fancy but uncontrollable shapes of tail fin, an unfittingly fat body, and loss of dorsal fins, provide us with a unique opportunity of studying artificial selection on phenotypic changes on the basis of molecular evolution. The aim of the present study is to elucidate the evolutionary origin and history of goldfish, taking into account the different characteristics of goldfish and human culture. Collecting 44 samples of a variety of goldfish from Japan and China as well as common and Crucian carps, we determined the nucleotide sequences for a substantial portion of mitochondrial genome including eight gene regions (D-loop, 12SrRNA, 16SrRNA, ND1, ND2, COI, ND5 and Cyt b) of approximately 11,180 bps. We, then, constructed phylogenetic trees for a total of 78 fishes, adding the 19 sequence data available in the international DNA database DDBJ/EMBL/GenBank to our 59 sequence data determined. From the phylogenetic trees obtained, we found that Japanese goldfish are not relative to Japanese Crucian carp (Carassius auratus langsdorfi) and that all the goldfish examined were originated from one of the two groups of the Chinese Crucian carp “Gibelio” (Carassius auratus gibelio). Moreover, we found that the process of artificial selection began from losing the dorsal fin followed by diversification of other characters such as eyes. This is supported by our further observations that the improvement of celestial and telescope eyes took place independently at different times, implying that goldfish was imposed by strong artificial selection only to meet diversified needs of human preferences in a unsystematic way. [Copyright &y& Elsevier]

Summary: Objective: Statins have been reported to be protective against myocardial infarction (MI). Moreover, statin drugs upregulate nitric oxide (NO) in coronary artery independent of lipid-lowering effects. However their precise mechanism for MI-protection is unclear. We investigated the effect of lipophilic statin administration in a normocholesterolemic rabbit MI model. Methods: Nω-nitro-l-arginine methylester (l-NAME, 10mg/kg) or vehicle alone was intravenously administered 20min before inducing ischemia, followed by intravenous administration of simvastatin (5mg/kg) or saline 10min before ischemia. Rabbits then underwent 30min of coronary occlusion followed by 48h of reperfusion. The at-risk and infarct areas were calculated as a percentage of the total left ventricular slice area. Results: Determination of infarct size revealed that pre-ischemic treatment with simvastatin reduced infarct size (30.5±4%) in comparison to controls (45.0±3%) (P <0.05). This infarct size-reducing effect of simvastatin could be completely abrogated by pretreatment with l-NAME (42.0±4%). Conclusions: Pre-ischemic treatment with simvastatin reduces MI size via NO production. Simvastatin could be a useful drug for coronary artery disease patients without dyslipidemia as it has direct protective effects. [Copyright &y& Elsevier]

Background Geriatric assessments (GAs) used to evaluate various aspects in elderly patients have recently been introduced for their usefulness in predicting toxicities of cancer treatments and subsequent patient prognoses. Utilizing GAs to decide on treatment policies has been recommended. However, there are few reports on the relationship between Geriatric 8 (G8), a screening tool for GA, and treatment outcomes of elderly patients with de novo acute myeloid leukemia (AML) who received low-dose chemotherapy (LDC). Patients and Methods We reviewed 47 patients aged≥70 years who were newly diagnosed with de novo AML (except for acute promyelocytic leukemia) and received LDC as an initial treatment at our hospital between April 2012 and June 2018. We divided them into two groups (high: N = 11, low: N = 36) according to G8 scores (cutoff: 14 points) at the time of diagnosis and retrospectively analyzed the differences in clinical features and treatment outcomes. Results Statistically significant differences in age (median, 73 vs. 79 years, p = 0.009) were observed between the two groups. The proportions of sex, median white blood cell and bone marrow blast counts, and percentages of patients with unfavorable cytogenetic abnormalities did not differ significantly between groups. The most frequent initial LDC in both groups was low-dose cytarabine combined with acrarubicine. The complete remission rate and overall survival at two years were significantly higher in the G8 high-score group than those in the low-score group (72.7% vs. 19.4%; p = 0.002 and 55.6% vs. 11.0%; p < 0.001), respectively. Early death from fatal infections, bleeding, and disease progression were frequently observed in the G8 low-score group (0.0% vs. 11.1%). Conclusion Our data suggest that G8 scores can predict treatment outcomes in elderly patients with de novo AML who received LDC. [ABSTRACT FROM AUTHOR]

Background & Aims Some studies have reported a high incidence of small bowel injuries in 60%–80% of subjects who take nonselective nonsteroidal anti-inflammatory drugs and PPIs simultaneously. We performed a randomized, double-blind, controlled study to determine whether proton pump inhibitors (PPIs) exacerbate nonsteroidal anti-inflammatory drug–induced small bowel injury. Methods Fifty-seven healthy subjects were randomly assigned groups given the cyclooxygenase (COX) 2 inhibitor celecoxib (200 mg, twice daily) plus placebo for 2 weeks (COX-2 + placebo group, n = 30), or celecoxib plus the PPI rabeprazole (20 mg, once daily) for 2 weeks (COX-2 + PPI group, n = 27). The study was performed from October 2012 through September 2013 at a tertiary medical center in Japan. All subjects were evaluated by capsule endoscopy at the start of the study and then after 2 weeks administration of celecoxib with rabeprazole or placebo. The incidence rates and the numbers of small bowel injuries (ulcers and erosions) that were observed under capsule endoscopy were compared between groups. The primary endpoint was the incidence of mucosal injuries at the second capsule endoscopy examination. Results A significantly higher proportion of subjects in the COX-2 + PPI group developed small bowel injury (12 of 27 subjects; 44.4%) than in the COX-2 + placebo group (5 of 30 subjects; 16.7%; P = .04). Subjects in the COX-2 + PPI group had a significant increase in risk of small bowel injury compared with the COX-2 + placebo group (relative risk, 2.67; 95% confidence interval, 1.08–6.58). The number of erosions in each member of the COX-2 + PPI group was greater than in each member of the COX-2 + placebo group ( P = .02). The number of ulcers did not differ between groups. Twenty-six percent of subjects in the COX-2 + PPI group developed mucosal injury in the jejunum, compared with none of the subjects in the COX-2 + placebo group ( P = .003); no such trend was found in the ileum. Conclusions In a randomized, controlled trial, PPIs increased the risk of short-term nonsteroidal anti-inflammatory drug–induced small bowel injury. UMIN clinical trial registry number: UMIN000008883. [ABSTRACT FROM AUTHOR]

Clathrin is a major component of clathrin-coated pits and serves as a binding scaffold for endocytic machinery through the binding of a specific sequence known as the clathrin-binding motif. This motif is also found in cellular signaling proteins other than endocytic components, including G protein-coupled receptor kinase 2 (GRK2), which phosphorylates G protein-coupled receptors and promotes uncoupling of receptor-G protein interaction. However, the functions of clathrin in the regulation of GRK2 are unknown. Here we demonstrated that overexpression of GRK2 mutated at the clathrin-binding motif with alanine (GRK2-5A) results in inhibition of phosphorylation and internalization of the β2-adrenergic receptor (β2AR). However, the interaction of β2AR with GRK2-5A is the same as that of wild type GRK2 as determined by bioluminescence resonance energy transfer. Furthermore, GRK2-5A phosphorylates rhodopsin essentially to the same extent as wild type GRK2 in vitro. Depletion of the clathrin heavy chain using small interference RNA inhibits agonist-induced phosphorylation and internalization of β2AR. Thus, clathrin works as a regulator of GRK2 in cells. These results indicate that clathrin is a novel player in cellular functions in addition to being a component of endocytosis. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease contributes significantly to mortality in end-stage renal disease (ESRD) patients. Single-photon emission computed tomography (SPECT) using an iodinated fatty acid analogue, iodine-123-methyl iodophenylpentadecanoic acid (123I-BMIPP), can assess fatty acid metabolism in the myocardium. We investigated the ability of 123I-BMIPP SPECT to detect coronary artery disease in hemodialysis patients compared with 201thallium chloride (201Tl) SPECT. Methods: We prospectively studied 130 ESRD patients undergoing hemodialysis for a mean of 88.6 months (male/female, 77/53; mean age, 63.8 years). Dual SPECT using 123I-BMIPP and 201Tl was performed, followed by coronary angiography. SPECT findings were graded in 17 segments on a five-point scale (0, normal uptake; 4, none) and assessed as a summed score. Results: By coronary angiography, 71.5% of patients (93/130) had significant coronary stenosis (> or =75%), and five patients showed coronary spasm without coronary stenosis. When a BMIPP summed score of 6 or more was defined as abnormal, sensitivity, specificity, and accuracy for detecting coronary artery disease by BMIPP SPECT were 98.0%, 65.6%, and 90.0%, respectively; in contrast, these parameters for detecting coronary artery disease by Tl SPECT were 84.7%, 46.9%, and 75.0%, respectively, when a Tl summed score of 1 or more was defined as abnormal. In receiver operating characteristic analysis, the area under the curve was 0.895 in BMIPP and 0.727 in Tl SPECT, respectively. Conclusion: Resting BMIPP SPECT is superior to Tl SPECT for detecting coronary lesions, and provides safe screening for coronary artery disease among maintenance hemodialysis patients. [ABSTRACT FROM AUTHOR]

We conducted a field experiment in soybean with different levels of K application to elucidate the comparative dynamics of 137Cs and K. The inventory of K in the shoots increased substantially from the fifth trifoliate stage to the full seed stage, and as the absorption of K increased, so too did the absorption of 137Cs. Overall, the effect of K application was much greater in terms of 137Cs dynamics than K dynamics or biomass production. K application reduced not only the accumulation of 137Cs in the shoots, but also the distribution of 137Cs to the grains. However, the decrease of 137Cs distribution to the grain had a much smaller effect on 137Cs accumulation in the grains than 137Cs absorption. A positive correlation was also observed between the exchangeable 137Cs/K ratio in the soil and the 137Cs/K ratio in the shoots for each growth stage, and the 137Cs/K ratios in the shoots at the full seed and full maturity stage were much higher than those at the fifth trifoliate and full bloom stage under the same exchangeable 137Cs/K ratio in the soil. These findings suggest a decrease in the discrimination of 137Cs from K during absorption after the full bloom stage. As a result of this and the increase in soil-exchangeable 137Cs/K with growth, radiocesium was more transferable to the shoots after the full bloom stage. Overall, these results suggest that lowering the soil-exchangeable radiocesium/potassium ratio after the full bloom stage by increasing K availability could efficiently reduce the transfer of radiocesium to the grains. • We conducted a field experiment in soybean with different levels of K application. • Comparative dynamics of 137Cs and K in soybean was elucidated. • K application reduced the absorption of 137Cs and the distribution of 137Cs to the grains. • Exchangeable 137Cs/K ratio in the soil and 137Cs/K in the shoots showed a linear correlation. • The slopes of these regression line changed substantially after the full seed stage. [ABSTRACT FROM AUTHOR]

Mirogabalin is a novel potent and selective ligand for the α 2 δ subunit of voltage-gated calcium channels, and shows potent and sustained analgesic effects in neuropathic pain and fibromyalgia models. Fibromyalgia is often associated with multiple comorbid symptoms, such as anxiety, depression and cognitive impairment. In the present study, we investigated the effects of mirogabalin on cognitive impairments in an experimental animal model for fibromyalgia, repeated intramuscular acidic saline injection model (Sluka model) rats. Male rats received two repeated intramuscular injections of pH 4 acidic saline into their gastrocnemius muscle. After developing mechanical hypersensitivity as identified in the von Frey test, the animals received the test substance orally once daily for 13 days and were subjected to four cognitive function tests, (Y-maze, novel object recognition, Morris water maze and step-through passive avoidance). Sluka model rats showed cognitive impairments in all four tests. Oral administration of mirogabalin (3 and 10 mg/kg) improved the cognitive impairments in these rats. In conclusion, mirogabalin improved the impaired cognitive function in Sluka model rats. It may thus also alleviate cognitive impairments as well as painful symptoms in fibromyalgia patients. [Display omitted] • Cognitive dysfunction is a quite common and problematic comorbidity in fibromyalgia. • Sluka model rats, an animal model for fibromyalgia, exhibited cognitive impairments. • The novel gabapentinoid mirogabalin improved cognitive function in Sluka model rats. • Mirogabalin may alleviate cognitive impairments as well as pain in fibromyalgia. [ABSTRACT FROM AUTHOR]

The important role of Gprotein-coupled receptor homo/heteromerization in receptor folding, maturation, trafficking, and cell surface expression has become increasingly evident. Here we investigated whether the humanδ-opioid receptor (hδOR) Cys-27 variant that shows inherent compromised maturation has an effect on the behavior of the more common Phe-27 variant in the early secretory pathway. We demonstrate that hδOR-Cys-27 acts in a dominant negative manner and impairs cell surface delivery of the coexpressed hδOR-Phe-27 and impairs conversion of precursors to the mature form. This was demonstrated by metabolic labeling, Western blotting, flow cytometry, and confocal microscopy in HEK293 and human SH-SY5Y neuroblastoma cells using differentially epitope-tagged variants. The hδOR-Phe-27 precursors that were redirected to the endoplasmic reticulum-associated degradation were, however, rescued by a pharmacological chaperone, the opioid antagonist naltrexone. Co-immunoprecipitation of metabolically labeled variants revealed that both endoplasmic reticulum- localized precursors and mature receptors exist as homo/heteromers. The existence of homo/heteromers was confirmed in living cells by bioluminescence resonance energy transfer measurements, showing that the variants have a similar propensity to form homo/heteromers. By forming both homomers and heteromers, the hδOR-Cys-27 variant may thus regulate the levels of receptors at the cell surface, possibly leading to altered responsiveness to opioid ligands in individuals carrying the Cys-27 variant. [ABSTRACT FROM AUTHOR]

Objectives: We hypothesized that erythropoietin (EPO)-immersed gelatin hydrogel microspheres (GHM) injected into ischemic legs might continuously release a small amount of EPO to locally stimulate angiogenesis without unfavorable systemic effects. Background: EPO is a potent angiogenic factor, but its use for relieving ischemic organs is limited because of the untoward systemic erythrogenic effect and its short half-life in plasma. Methods: The right femoral arteries of BALB/c mice were ligated. Recombinant human EPO (5,000 IU/kg)-immersed GHM was injected into the right hind limb muscles (n = 12); the control groups included a saline-injected group (n = 12), an EPO-injected group (n = 8), and an empty GHM-injected group (n = 8). Results: Eight weeks later, improvement of blood perfusion to the ischemic limb was significantly augmented in the EPO-GHM group compared with any of the control groups. There was no increase in the hemoglobin level, nor was there any increase in endothelial progenitor cells. However, capillary and arteriolar densities were significantly increased in this group. Although the treatment did not affect the levels of vascular endothelial growth factor or interleukin-1 beta, it up-regulated the EPO receptor and matrix metalloproteinase-2 and activated the downstream signaling of Akt and also endothelial nitric oxide synthase in ischemic limbs, which might have been associated with the evident angiogenic and arteriogenic effects in the present system. Conclusions: The present drug delivery system is suggested to have potential as a novel noninvasive therapy for ischemic peripheral artery disease. [Copyright &y& Elsevier]

We prospectively evaluated if impaired myocardial fatty acid metabolism is involved in cardiac death after revascularization by percutaneous coronary artery intervention in dialysis patients. A cohort of hemodialysis patients was assessed by dual single-photon emission computed tomography using the radioiodinated fatty acid analogue BMIPP and radiolabeled thallium chloride. Tomography was done within one month before the first coronary intervention and at the last follow-up angiography at which neither restenosis nor de novo lesions were detected. Radiolabel uptake on tomography images was graded in segments and calculated as summed BMIPP or thallium scores. Among the 90 hemodialysis patients in the study, 19 died of cardiac events. Multivariate Cox hazard analysis found a significant association of cardiac death with the BMIPP summed scores at the last follow-up angiography. Kaplan–Meier analysis showed the cardiac death-free survival rates at 3 years of follow-up were significantly higher in patients with lower BMIPP summed scores. These results suggest that myocardial fatty acid imaging may be a useful test to identify high risk groups of cardiac death in hemodialysis patients.Kidney International (2008) 74, 513–520; doi:10.1038/ki.2008.211; published online 4 June 2008 [ABSTRACT FROM AUTHOR]

Angiotensin II (Ang II) activates multiple signaling pathways leading to hyperplasia of cardiac fibroblasts. Reactive oxygen species (ROS) produced by Ang II stimulation are assumed to play pivotal roles in this process. Here, we show that ROS mediate Ang II-induced activation of nuclear factor of activated T cells (NFAT) in rat cardiac fibroblasts. Ang II-induced NFAT activation was suppressed by diphenyleneiodonium (an NADPH oxidase inhibitor), dominant negative (DN)-Rac, DN-p47phox, and an inhibitor of Gα12/13 (Gα12/13-specific regulator of G protein signaling domain of p115RhoGEF, p115-regnlator of G protein signaling (RGS)). Stimulation of Ang II receptor increased the intracellular ROS level in a Rac- and p47phox-dependent manner. Because p115-RGS suppressed Aug II-induced Rac activation, Aug II receptor-coupled Gα12/13 mediated NFAT activation through ROS production by Rac activation. Aug II-induced nuclear translocation of the green fluorescent protein (GFP)-tagged Amino-terminal region of NFAT4 (GFP-NFAT4) was suppressed by p115-RGS or BAPTA but not by diphenyleneiodonium. The expression of constitutively active (CA)-Gα12, CA-Gα13, or CA-Rac increased the nuclear translocation of GFP-NFAT4. These results suggest that NFAT activity is regulated by both Ca2+-dependent and ROS-dependent pathways. Furthermore, activation of c-Jun NH2-terminal kinase (JNK) induced by Aug II stimulation is required for NFAT activation because Aug II-induced NFAT activation was inhibited by SP600125, a selective JNK inhibitor. These results indicate that Aug II stimulates the nuclear translocation and activation of NFAT by integrated pathways including the activation of Gα12/13, Rac, NADPH oxidase, and JNK and that Gα12/13-mediated ROS production is essential for N-FAT transcriptional activation. [ABSTRACT FROM AUTHOR]

In the present study, we examined signal transduction mechanism of reactive oxygen species (ROS) production and the role of ROS in angiotensin II-induced activation of mitogen-activated protein kinases (MAPKs) in rat neonatal cardiomyocytes. Among three MAPKs, c-Jun NH2-terminal kinase (JNK) and p38 MAPK required ROS production for activation, as an NADPH oxidase inhibitor, diphenyleneiodonium, inhibited the activation. The angiotensin II-induced activation of JNK and p38 MAPK was also inhibited by the expression of the Gα2/13-specific regulator of G protein signaling (RGS) domain, a specific inhibitor of Gα12/13, but not by an RGS domain specific for Gαq. Constitutively active Gα12- or Gα13-induced activation of JNK and p38 MAPK, but not extracellular signal-regulated kinase (ERK), was inhibited by diphenyleneiodonium. Angiotensin II receptor stimulation rapidly activated Gα13, which was completely inhibited by the Gα12/13-specific RGS domain. Furthermore, the Gα12/13-specific but not the Gαq-Specific RGS domain inhibited angiotensin II-induced ROS production. Dominant negative Rac inhibited angiotensin II-stimulated ROS production, JNK activation, and p38 MAPK activation but did not affect ERK activation. Rac activation was mediated by Rho and Rho kinase, because Rac activation was inhibited by C3 toxin and a Rho kinase inhibitor, Y27632. Furthermore, angiotensin II-induced Rho activation was inhibited by Gα12/13-specific RGS domain but not dominant negative Rac. An inhibitor of epidermal growth factor receptor kinase AG1478 did not affect angiotensin II-induced JNK activation cascade. These results suggest that Gα12/13-mediated ROS production through Rho and Rac is essential for JNK and p38 MAPK activation. [ABSTRACT FROM AUTHOR]

The DNA methylation inhibitor azacitidine (5-azacytidine) is used against myelodysplastic syndrome and acute myeloid leukemia, but drug resistance is an ongoing, intractable problem. To investigate resistance mechanisms, we generated two azacitidine-resistant cell lines, THP-1/AR and HL60/AR, and studied genetic disparities between them and their corresponding parental lines. In cells treated with azacitidine, significant mitotic variations were noted in parental cells which were absent in resistant cells, suggesting that resistance arises from negating azacitidine-mediated activation of apoptosis signaling and reestablishing G2/M checkpoint. Importantly, both resistant cell lines have common point mutations in the uridine-cytidine kinase 2 (UCK2) gene, which encodes the rate-limiting enzyme of the azacitidine activation pathway. Forced expression of mutated UCK2 in parental THP-1 cells abrogated azacitidine-induced apoptosis, whereas overexpression of wild type UCK2 in resistant THP-1/AR cells restored sensitivity to azacitidine, implying that UCK2 gene mutations perturb azacitidine activation and advance azacitidine resistance. Our study provides new insights into azacitidine resistance and establishes models useful in developing effective strategies to overcome it. [Copyright &y& Elsevier]