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Background: Given that residual congestion is a predictor of poor outcome in patients with heart failure (HF), a therapeutic strategy for decongestion is required. Methods and Results: Eighteen HF patients with fluid retention despite oral furosemide >20 mg/day, with chronic kidney disease (CKD; estimated glomerular filtration rate [eGFR]

GLP-1 has been reported to be cardioprotective against ischemia-reperfusion injury. We aimed to examine the effect of alogliptin, which may produce GLP-1, on ischemia-reperfusion injury and its mechanisms. Rabbits were fed a normal chow (control group) and a chow containing alogliptin (2 mg·kg·d: alogliptin-L group and 20 mg·kg·d: alogliptin-H group) for 7 days. The rabbits underwent 30 minutes of coronary occlusion and 48 hours of reperfusion. Exendin (9-39) [5 or 50 μg/kg, i.v., alogliptin-H+exendin (9-39)-L group and alogliptin-H+exendin (9-39)-H group] or L-NAME (10 mg/kg, i.v., alogliptin-H+L-NAME group) was administered to the alogliptin-H group. Alogliptin dose-dependently reduced the infarct size, which was partially blocked by exendin (9-39), but completely blocked by L-NAME. Exendin (9-39) or L-NAME alone did not affect the infarct size for themselves. The left ventricular ejection fraction and ±dP/dt were higher in the alogliptin-L group and alogliptin-H group than in the control group. Alogliptin increased the serum NOx and plasma GLP-1 levels, and those levels inversely correlated with the infarct size. Alogliptin upregulated the expressions of phosphorylated (p)-Akt and p-eNOS, which were inhibited by exendin (9-39) and L-NAME, respectively. In conclusion, alogliptin protects the heart against ischemia-reperfusion injury through GLP-1 receptor-dependent and receptor-independent pathways which involve nitric oxide production in rabbits.

This study aimed to investigate the effect of combination of high-salt intake and hypertension on renal functional and histological damage, associated with renal (pro)renin receptor [(P)RR] and AT1 receptor in rats. Wistar Kyoto rats (WKYs) and spontaneously hypertensive rats (SHRs) received regular rat chow (normal-salt diet 0.9%) or high-salt rat chow (high-salt diet 8.9%) for 6 weeks from 6 to 12 weeks of age. Systolic blood pressure, serum creatinine and blood urea nitrogen (BUN) were measured. Histological analysis of the kidney was performed. Western blot analysis was performed on the expressions of (P)RR, angiotensinogen and AT1 receptor in the kidney. High-salt intake significantly increased systolic blood pressure in WKYs and especially in SHRs. High-salt intake significantly increased serum creatinine and BUN, and accelerated renal tubulointerstitial fibrosis and glomerular sclerosis in SHRs. High-salt intake significantly enhanced the renal tissue expressions of (P)RR, angiotensinogen and AT1 receptor in SHRs. High-salt intake accelerates functional and histological renal damage associated with renal tissue overexpression of (P)RR and AT1 receptors in SHRs.

AimsGlucagon-like peptide-1 (GLP-1) is a neuroendocrine hormone secreted by the intestine. Its receptor (GLP-1R) is expressed in various organs, including the heart. However, the dynamics and function of the GLP-1 signal in heart failure remains unclear. We investigated the impact of the cardio-intestinal association on hypertensive heart failure using miglitol, an α-glucosidase inhibitor known to stimulate intestinal GLP-1 production.Methods and resultsDahl salt-sensitive (DS) rats fed a high-salt diet were assigned to miglitol, exendin (9-39) (GLP-1R blocker) and untreated control groups and treated for 11 weeks. Control DS rats showed marked hypertension and cardiac dysfunction with left ventricular dilatation accompanied by elevated plasma GLP-1 levels and increased cardiac GLP-1R expression as compared with age-matched Dahl salt-resistant (DR) rats. Miglitol further increased plasma GLP-1 levels, suppressed adverse cardiac remodelling, and mitigated cardiac dysfunction. In cardiomyocytes from miglitol-treated DS hearts, mitochondrial size was significantly larger with denser cristae than in cardiomyocytes from control DS hearts. The change in mitochondrial morphology reflected enhanced mitochondrial fusion mediated by protein kinase A activation leading to phosphorylation of dynamin-related protein 1, expression of mitofusin-1 and OPA-1, and increased myocardial adenosine triphosphate (ATP) content. GLP-1R blockade with exendin (9-39) exacerbated cardiac dysfunction and led to fragmented mitochondria with disarrayed cristae in cardiomyocytes and reduction of myocardial ATP content. In cultured cardiomyocytes, GLP-1 increased expression of mitochondrial fusion-related proteins and ATP content. When GLP-1 and exendin (9-39) were administered together, their effects cancelled out.ConclusionsIncreased intestinal GLP-1 secretion is an adaptive response to heart failure that is enhanced by miglitol. This could be an effective strategy for treating heart failure through regulation of mitochondrial dynamics.

Purpose: As laser speckle flowgraphy can measure blood flow distribution in the ocular fundus, the authors analyzed the relationship between retinal blood flow and aqueous vascular endothelial growth factor (VEGF) concentration in central retinal vein occlusion. Methods: This prospective observational study examined 45 eyes of 45 patients with central retinal vein occlusion before treatment. Blood flow in large vessels around and at the optic disk, aqueous VEGF concentration, and arteriovenous passage time were examined. Blood flow was evaluated as mean blur rate by laser speckle flowgraphy. Results: Fluorescein angiography found 20 ischemic and 25 nonischemic type eyes. Aqueous VEGF concentration in the ischemic type was significantly higher than that in the nonischemic type (P = 0.01). Arteriovenous passage time was significantly correlated to the logarithm of the aqueous VEGF concentration (P = 0.0001). Mean blur rate of the affected eye/ mean blur rate of the unaffected eye of the ischemic type was significantly lower than the nonischemic type (P = 0.039). Additionally, mean blur rate was significantly correlated both to the logarithm of the aqueous VEGF concentration (P , 0.0001) and to the arteriovenous passage time (P = 0.0001). Conclusion: Laser speckle flowgraphy may be useful for predicting aqueous VEGF concentration and severity of central retinal vein occlusion., Retina, 35(10), pp.2037-2042; 2015

Few studies have analyzed Cathepsin K (CatK) expression in human osteoarthritic tissues. We investigated CatK expression and activation in human articular cartilage using clinical specimens. Human osteoarthritic cartilage was obtained during surgery of total hip arthroplasty (n = 10), and control cartilage was from that of femoral head replacement for femoral neck fracture (n = 10). CatB, CatK, CatL, CatS, and Cystatin C (CysC) expressions were evaluated immunohistochemically and by real-time PCR. Intracellular CatK protein was quantified by ELISA. Intracellular CatK activity was also investigated. Osteoarthritis (OA) chondrocytes were strongly stained with CatK, particularly in the superficial layer and more damaged areas. CatB, CatL, CatS, and CysC were weakly stained. CatK mRNA expression was significantly higher in OA group compared to that in control group (p = 0.043), whereas those of CatB, CatL, CatS, and CysC did not differ significantly. Mean CatK concentration (4.83 pmol/g protein) in OA chondrocytes was higher than that (3.91 pmol/g protein) in control chondrocytes (p = 0.001). CatK was enzymatically more activated in OA chondrocytes as compared with control chondrocytes. This study, for the first time, revealed increased CatK expression and activation in human OA cartilage, suggesting possible crucial roles for it in the pathogenesis of osteoarthritic change in articular cartilage.

A wet-chemical approach using DNA extracted from salmon milt as a template to mass produce Ag nanoparticles was developed. Spherical Ag nanoparticles with a main diameter of less than 10 nm were obtained. The concentration of Ag nanoparticles in the as-produced colloidal suspension was as high as 5.3 × 10−2 mol l−1. This simple and effective procedure should offer an alternative route to the mass production of Ag nanoparticles for practical applications. A wet-chemical approach using DNA extracted from salmon milt as a template to mass produce Ag nanoparticles was developed. Spherical Ag nanoparticles with a main diameter of less than 10 nm were obtained. The concentration of Ag nanoparticles in the as-produced colloidal suspension was as high as 5.3 × 10−2 mol l−1. This simple and effective procedure should offer an alternative route to the mass production of Ag nanoparticles for practical applications.

Background: To evaluate the prognostic factors for the best-corrected visual acuity (BCVA) and foveal average retinal thickness after vitrectomy with internal limiting membrane (ILM) peeling for diabetic macular edema. Design: Retrospective, single-center study. Participants: This study involved 31 eyes of 27 patients who had undergone vitrectomy with ILM peeling between January 2005 and March 2008. Methods: Relationships between preoperative systemic or ocular factors and BCVA or foveal average retinal thickness before and 6 months after the operation were evaluated. Main Outcome Measures: BCVA and foveal average retinal thickness before and 6 months after the operation. Results: The mean logarithm of the minimum angle of resolution improved from 0.84 ± 0.64 (mean ± standard deviation) preoperatively to 0.64 ± 0.38 six months postoperatively (p = 0.393). Foveal average retinal thickness significantly improved from 473 ± 146 μm preoperatively to 318 ± 108 μm 6 months after the operation (p < 0.0001). Preoperative foveal average retinal thickness was significantly thicker with cardiovascular disease or cerebral infarction (p = 0.0019) or cystoid macular edema (p = 0.0028), while preoperative BCVA was significantly lower when an epiretinal membrane (p = 0.042) was present. Foveal average retinal thickness at the 6-month follow-up was significantly thicker when patients had a higher body mass index (p = 0.0088), were not on dialysis (p = 0.012), or did not have proliferative diabetic retinopathy (p = 0.013). BCVA at the 6-month follow-up was significantly lower in the group with no history of diabetes treatment until diabetic retinopathy was found (p = 0.023) and in patients with a higher preoperative glycosylated hemoglobin (p = 0.033). Conclusions: Preoperatively, BCVA and foveal average retinal thickness were primarily associated with ocular factors, while they were strongly associated with systemic factors, postoperatively. Ocular factor improvements may be related to the surgical procedure., Ophthalmologica, 229(3), pp.142-146; 2013

A retrospective observational case series study of 44 nonischemic central retinal vein occlusion (CRVO) patients was conducted and visual acuity, central retinal thickness, and blood flow were determined via the use of laser speckle flowgraphy. This study shows that blood flows after intravitreal bevacizumab can predict outcomes in patients with CRVO., Purpose: To investigate whether retinal blood flow levels after intravitreal bevacizumab (IVB) treatment are correlated with the outcomes of patients with macular edema secondary to central retinal vein occlusion. Methods: This retrospective observational case study enrolled 44 cases nonischemic central retinal vein occlusion. In each patient, visual acuity, central retinal thickness, and mean blur rate, which was measured by laser speckle flowgraphy and represents retinal blood flow velocity, were examined. Results: At the end of the follow-up period (19.8 ± 8.8 months), 4 of 44 eyes (9.1%) converted to the ischemic type (converted group), whereas 40 (90.9%) remained unchanged (nonischemic group). Mean central retinal thickness significantly decreased and mean visual acuity significantly improved at 1 month after the first IVB injection in each group. Mean mean blur rate in the nonischemic group significantly increased, whereas it was unchanged in the converted group. The difference between the two groups was already significant after the first IVB injection. Subsequently, visual acuity worsened in the converted group. Multiple linear regression analysis indicated that the strongest correlation was between the last visual acuity and the last mean blur rate. Conclusion: Blood flow measurements are useful for evaluating IVB treatments. Blood flow after IVB can predict outcomes in patients with central retinal vein occlusion.

Summary 1. The present study examined whether or not cilostazol reduces the myocardial infarct size, and investigated its mechanism in a rabbit model of myocardial infarction. 2. Japanese white rabbits underwent 30 min of coronary occlusion, followed by 48 h of reperfusion. Cilostazol (1 and 5 mg/kg) or vehicle was given intravenously 5 min before ischaemia. 8-p-sulfophenyl theophylline (8SPT; an adenosine receptor blocker, 7.5 mg/kg), Nω-nitro-l-arginine methylester (l-NAME; an NOS inhibitor, 10 mg/kg) or 5-hydroxydecanoic acid sodium salt (5-HD; a mitochondrial ATP-sensitive potassium (KATP) channel blocker, 5 mg/kg) was given intravenously 5 min before cilostazol injection. Infarct size was determined as a percentage of the risk area. 3. The myocardial interstitial levels of adenosine and nitrogen oxide (NOx) during ischaemia and reperfusion, and the intensity of myocardial dihydroethidium staining were determined. 4. Infarct size was significantly reduced in the cilostazol 1 mg/kg (38.4% (2.9%)) and cilostazol 5 mg/kg (30.7% (4.7%)) groups compared with that in the control group (46.5% (4.2%)). The infarct size-reducing effect of cilostazol was completely abolished by 8SPT (46.6% (3.5%)), l-NAME (49.0% (5.5%)), or 5HD (48.5% (5.1%)). 8SPT, l-NAME or 5HD alone did not affect the infarct size. Cilostazol treatment significantly increased myocardial levels of adenosine and NOx during ischaemia, and attenuated the intensity of dihydroethidium staining during reperfusion. 5. These findings show that cilostazol reduces the myocardial infarct size by increasing adenosine and NOx levels, attenuating superoxide production and opening the mitochondrial KATP channels. Cilostazol might provide a new strategy for the treatment of coronary heart disease.

Granulocyte colony-stimulating factor (G-CSF) has been reported to improve cardiac function after myocardial infarction. However, whether postinfarct acute effect of G-CSF is mediated through the same signaling pathways as those of ischemic postconditioning is still unclear. We examined the postinfarct acute effect of G-CSF on myocardial infarct size and its precise molecular mechanism. Japanese white rabbits underwent 30 min of ischemia and 48 h of reperfusion. Rabbits were intravenously injected 10 μg/kg of G-CSF (G-CSF group) or saline (control group) immediately after reperfusion. The wortmannin + G-CSF, PD-98059 + G-CSF, Nω-nitro-l-arginine methyl ester (l-NAME) + G-CSF, and 5-hydroxydecanoic acid sodium salt (5-HD) + G-CSF groups were respectively injected with wortmannin (0.6 mg/kg), PD-98059 (0.3 mg/kg), l-NAME (10 mg/kg), and 5-HD (5 mg/kg) 5 min before G-CSF administration. Myocardial infarct size was calculated as a percentage of the risk area of the left ventricle. Western blot analysis was performed to examine the signals such as protein kinase B (Akt), extracellular signal-regulated protein kinase (ERK), eNOS, p70S6 kinase (p70S6K), and glycogen synthase kinase-3β (GSK3β) in the ischemic myocardium after 48 h of reperfusion. The infarct size was significantly smaller in the G-CSF group (26.7 ± 2.7%) than in the control group (42.3 ± 4.6%). The infarct size-reducing effect of G-CSF was completely blocked by wortmannin (44.7 ± 4.8%), PD-98059 (38.3 ± 3.9%), l-NAME (42.1 ± 4.2%), and 5-HD (42.5 ± 1.7%). Wortmannin, PD-98059, l-NAME, or 5-HD alone did not affect the infarct size. Western blotting showed higher myocardial expression of phospho-Akt, phospho-ERK, phosho-eNOS, phosho-p70S6K, and phosho-GSK3β at 10 min and 48 h after reperfusion in the G-CSF group than in the control group. In conclusion, postreperfusion G-CSF administration reduces myocardial infarct size via activation of phosphatidylinositol 3-kinase-Akt and ERK prosurvival signaling pathways and their downstream targets eNOS, p70S6 kinase, GSK3β, and mitochondrial ATP-dependent K+ channel.

BACKGROUND Acarbose, an antidiabetic drug, is an alpha-glucosidase inhibitor that can inhibit glucose absorption in the intestine. A recent large-scale clinical trial, STOP-NIDDM, showed that acarbose reduces the risk of myocardial infarction. We examined whether acarbose reduces myocardial infarct size and investigated its mechanisms. METHODS AND RESULTS Rabbits were fed with 1 of 2 diets in this study: normal chow, 30 mg acarbose per 100 g chow for 7 days. Rabbits were assigned randomly to 1 of 4 groups: control (n = 10), acarbose (n = 10), acarbose + 5HD (n = 10, intravenous 5 mg/kg of 5-hydroxydecanoate), and 5HD (n = 10, intravenous 5 mg/kg of 5HD). Rabbits then underwent 30 minutes of coronary occlusion followed by 48-hour reperfusion. Postprandial blood glucose levels were higher in the control group than in the acarbose group. The infarct size as a percentage of the left ventricular area at risk was reduced significantly in the acarbose (19.4% +/- 2.3%) compared with the control groups (42.8% +/- 5.4%). The infarct size-reducing effect of acarbose was abolished by 5HD (43.4% +/- 4.7%). Myocardial interstitial 2,5-dihydroxybenzoic acid levels, an indicator of hydroxyl radicals, increased during reperfusion after 30 minutes of ischemia, but this increase was inhibited in the acarbose group. This was reversed by 5HD. CONCLUSION Acarbose reduces myocardial infarct size by opening mitochondrial KATP channels, which may be related to the prevention of postprandial hyperglycemia and hydroxyl radical production.

Candesartan has been reported to produce nitric oxide (NO) and to decrease oxidative stress in animal studies. We investigated candesartan's effect on the production of NO and oxidative stress as well as on carotid intima-media thickness (IMT) in hypertensive patients. One-hundred age-matched hypertensive patients were enrolled into an angiotensin II receptor blocker (ARB) group (n=50) or a non-ARB group (n=50). The ARB group was treated with candesartan 8 mg and, when needed, Ca channel blockers, angiotesin-converting enzyme (ACE) inhibitors, and/or beta-blockers. The non-ARB group was treated with drugs other than ARB. Carotid IMT was assessed by echocardiography before and 12 and 24 months after treatment. The urine levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), an indicator of oxidative stress, and the serum levels of NOx, an indicator of NO, were measured. Blood pressure decreased to below 140/90 mmHg to the same extent in both groups. Carotid IMT decreased significantly in the ARB group, but not in the non-ARB group, at 12 and 24 months after treatment. The urine levels of 8-OHdG decreased significantly at 6 and 12 months after treatment in the ARB group but did not decrease in the non-ARB group. The serum levels of NOx increased significantly at 6 and 12 months after treatment in the ARB group but not in the non-ARB group. In conclusion, candesartan decreases carotid IMT by enhancing NO production and decreasing oxidative stress in patients with hypertension.

The aim of this study was to determine type I collagen turnover in giant cell tumor of bone (GCT) by biochemical markers of type I procollagen aminoterminal propeptide (PINP) and type I collagen carboxyterminal telopeptide (ICTP) as synthesis and degradation markers, respectively. The serum concentrations of PINP and ICTP were measured in 11 patients with GCT using radioimmunoassay, and analyzed by the correlation to the grades of GCT progression described by Campanacci. Serum of the 11 healthy subjects was available for comparison. The serum concentration of PINP was significantly higher in patients with GCT (82.4 +/- 46.2 ng/ml) than in controls (40.8 +/- 12.1 ng/ml) (P0.01), and that of ICTP was also significantly higher in GCT (5.3 +/- 2.0 ng/ml) than in controls (3.2 +/- 0.8 ng/ml) (P0.01). In GCT, the PINP concentration of grade 3 (127.6 +/- 38.8 ng/ml) was higher than that in grade 1 patients (46.9 +/- 4.8 ng/ ml) (P0.01). ICTP concentration of both grades 2 (7.1 +/- 1.4 ng/ml) and 3 (5.8 +/- 1.8 ng/ml) patients was significantly higher than that of grade 1 (3.5 +/- 0.6 ng/ ml) patients (P0.01, P0.05, respectively). Two cases of serum concentration of PINP and ICTP after resection of GCT demonstrated that these biomarkers decreased to the control levels in the absence of GCT. Our results indicated that type I collagen turnover evaluated by ICTP and PINP was stimulated in the presence of GCT. Moreover, this enhanced metabolic turnover reflects the grade of GCT.

Objective A high salt intake causes hypertension and leads to cardiovascular disease. Therefore, a low salt diet is now recommended to prevent hypertension and cardiovascular disease. However, it is still unknown whether an excessively low salt diet is beneficial or harmful for the heart. Methods Wistar Kyoto rats (WKYs) and spontaneously hypertensive rats (SHRs) received normal salt chow (0.9% salt diet) and excessively low salt chow (0.01% salt diet referred to as saltless diet) for 8 weeks from 8 to 16 weeks of age. The effects of the excessively low salt diet on the cardiac (pro) renin receptor, renin-angiotensin-aldosterone, and sympatho-adrenal systems were investigated. Results The excessively low salt diet did not affect the systolic blood pressure but significantly increased the heart rate both in WKYs and SHRs. The excessively low salt diet significantly elevated plasma renin activity, plasma angiotensin I, II and aldosterone concentrations, and plasma noradrenaline and adrenaline concentrations both in WKYs and SHRs. Cardiac expressions of renin, prorenin, (P)RR, angiotensinogen, and angiotensin II AT1 receptor and phosphorylated (p)-ERK1/2, p-HSP27, p-38MAPK, and TGF-s1 were significantly enhanced by the excessively low salt diet in both WKYs and SHRs. The excessively low salt diet accelerated cardiac interstitial and perivascular fibrosis and increased the cardiomyocyte size and interventricular septum thickness in WKYs and SHRs but the extent was greater in SHRs. Conclusion An excessively low salt diet damages the heart through activation of plasma renin-angiotensin-aldosterone and sympatho-adrenal systems and activation of cardiac (P)RR and angiotensin II AT1 receptor and their downstream signals both in WKYs and SHRs.

We conducted a prospective randomized trial to assess the protective effect of continuous intravenous infusion of nicorandil against contrast-induced nephropathy (CIN) in patients with poor renal function.We randomly assigned 213 patients who would subsequently undergo elective percutaneous coronary intervention (PCI) and who had a high serum cystatin C level to a saline group (n=107) or a nicorandil group (n=106, nicorandil infused in addition to saline for 4h before and 24h after PCI). There were no significant differences in baseline characteristics between the two groups. However, the average percent increases in serum creatinine and cystatin C following PCI were significantly smaller in the nicorandil group than the saline group. Likewise, the average percent decline in the estimated glomerular filtration rate was smaller in the nicorandil group. Correspondingly, the incidence of CIN was dramatically lower in the nicorandil group than the saline group (2.0% vs. 10.7%, p0.02). Univariate regression analysis revealed nicorandil treatment to be the only significant predictor of CIN development (odds ratio: 0.173, 95% confidence interval: 0.037-0.812, p=0.026).Nicorandil strongly prevents CIN in patients with poor renal function undergoing PCI.

Dynamics of photoreaction of permethylcycloheptasilane (Me2Si)7 on the triplet state surface, (Me2Si)7 (T1) →> (Me2Si)6 + Me2Si (T1), has been investigated by means of the direct MO dynamics method in order to elucidate mechanism of silylene extrusion from the Si-ring following the triplet energy transfer from a carbonyl compound. Full dimensional potential energy surface calculated at the PM3 method was employed in the dynamics calculation: the total energy and energy gradient on each atom were calculated at each time step during the reaction. The calculations showed that the seven-membered Si-ring is spontaneously changed to the six-membered ring without activation barrier on T1 surface. The photoreaction of (Me2Si)7 is significantly fast (reaction is completed within 1.0 ps), although heavy molecule (silylene radical) is dissociated. This is due to the fact that the T1 surface is strongly repulsive for the coordinate between the silylene and the Si-ring. The mechanism of the silylene extraction from the Si-ring was discussed on the basis of theoretical results.Key words: direct MO dynamics, polysilane, photoreaction, permethylcycloheptasilane, silylene.

Comparison of the ESR and electronic absorption spectra of the radical ions of poly(cyclohexylmethylsilane) and poly(n-decyl-(s)-2-methylbutylsilane) has shown that the Anderson localization of charge carriers on part of the Si–Si polymer skeleton can be suppressed by replacing the pendant groups with bulky ones. Replacement reduces the flexibility of the polymer skeleton and therefore the dispersion of the resonance energies of the charge carriers between adjacent Si atoms, which suppresses the localization of the charge carriers arising from irregularity of the periodic potential field on the skeleton.

Mechanism of photo-reaction of permethylcyclopentasilane (Me2Si)5 on the triplet excited state surface, (Me2Si)5 (T1) → (Me2Si)4 + Me2Si:, has been investigated by means of direct molecular orbital (MO) dynamics method. Full dimensional potential energy surface calculated at the PM3 level was employed in the dynamics calculation: the total energy and energy gradient on each atom were calculated at each time step during the reaction. The vertical electronic transition from the ground (S0) to the first excited triplet (T1) states was assumed in the classical trajectory calculation. The calculations showed that the five-membered Si-ring is spontaneously changed to the four-membered ring without activation barrier on the T1 surface. The photo-reaction of (Me2Si)5 is slightly faster than that of (Me2Si)6 due to the strong steric hindrance. Mechanism of the extrusion of silylene radical from the Si ring was discussed on the basis of theoretical results.

N -acyl- l -alanine oligomer potassium salts (CH 3 (CH 2 ) n CO(NHCH(CH 3 )CO) m O − K + , n =0, 2, 4, 6 and 8, m =3 and 4) have been synthesized. Raman spectroscopic evidence for a conformational change of the oligomer anions in aqueous solution is reported. The Raman scattering spectra of sample solutions diluted below the critical micelle concentration (cmc) are accounted for by postulating the coexistence of several conformations containing the α -helix, β -sheet, and β -turn structures. Above the cmc, the Raman bands for the amide I, III and skeletal stretch modes which are characteristic of an α -helix become more intense and this result is ascribed to preferential stabilization of the helical structure, promoted by intermolecular association of oligomer anions.

Potassium salts of N-decanoylglycine and N-decanoyl-L-alanine oligopeptides (monomer, dimer and trimer) were synthesized. For these oligomer salts in aqueous solutions, the microstructures of micelles have been investigated by small-angle neutron-scattering (SANS). In the calculation of SANS intensity data, the thickness of the hydrophilic layer was altered by changing the conformation of the oligomer moiety (helical and β-sheet structures). For micelles of the trimer salts, the helical structure models provide the best fit to the observed SANS intensity data. For micelles of the monomer- and dimer-salts, the β-sheet model provides the best fit to the observed data. For the monomer-and dimer-micelles, the aggregation number (n) is not dependent on the species of amino acid residue, implying that the decanoyl group plays a critical role in micelle formation. However, for the trimer micelles, the n value is dependent on the species of amino acid residue.

Trimers and tetramers of N- acyl- l -alanine oligomer acid types with various acyl chains (acetyl, butanoyl, hexanoyl and octanoyl groups), their potassium (K) salts and their benzylesters have been synthesized. The vibrational spectra of these oligomers have been measured and compared with those of α-helical and β-sheet poly( l -alanine). A conformation similar to β-poly( l -alanine) was found in the solid state for these oligopeptides. The long acyl chains induce a further β-sheet structure in the hydrogen bonding of the peptide skeleton. This effect is reflected by noticeable changes in the NH stretching, amide-characteristic vibrational modes and low frequency regions.

We evaluated central retinal thickness (CRT) in diabetic macular edema (DME) using two different spectral-domain (SD) optical coherence tomography (OCT) instruments: the Cirrus and Spectralis OCTs. CRT was measured in 63 eyes of 32 patients with DME using both instruments on the same day. CRT measurements were significantly greater for the Spectralis than the Cirrus (p

(S)-5-Iodonicotine (4a), an (S)-nicotine analog iodinated at the 5-position of the pyridine ring, was synthesized and evaluated as a potential radiopharmaceutical for investigating brain nicotine receptors by single photon emission computerized tomography (SPECT). [125I]-(S)-5-Iodonicotine ([125I]-4a) was synthesized by the iododestannylation reaction under no-carrier-added conditions and purified by high-performance liquid chromatography (HPLC). The binding affinity of 4a for brain nicotine receptors was measured in terms of displacement of [3H]cytisine from binding sites in rat cortical membranes. The binding data revealed that the affinity of 4a was the same as that of (S)-nicotine and 80-fold higher than that of the (R)-enantiomer (4b). Biodistribution studies in mice disclosed that the brain uptake of [l>I]-4a was rapid and profound. Regional cerebral distribution studies in rats by autoradiography disclosed that the accumulation of [125I]-4a was dense in the thalamus, intermediate in the cortex and striatum, and less marked in the cerebellum. Furthermore, the administration of (S)-nicotine reduced the uptake of [125I]-4a in the thalamus and resulted in a nearly identifal level of radioactivity in the cerebellum. [125I]-(R)-5-Iodonicotine ([125I]-4b) showed more rapid washout from the brain and a less extensive regional cerebral distribution than the (S)-enantiomer ([125I]-4a). Thus, 4a bound to brain nicotine receptors in vivo, and therefore iodine-123-labeled 4a may be a potential radioligand for use in in vivo cerebral nicotinic receptor studies by SPECT.

Glucagon-like peptide 1 (GLP-1) reportedly exerts a protective effect against cardiac ischemia. We hypothesized that the alpha-glucosidase inhibitor voglibose, an unabsorbable antidiabetic drug with cardioprotective effects, may act through stimulation of GLP-1 receptors. The results of the present study suggest oral administration of voglibose reduces myocardial infarct size and mitigates cardiac dysfunction in rabbits after 30 minutes of coronary occlusion and 48 hours of reperfusion. Voglibose increased basal and postprandial plasma GLP-1 levels and reduced postprandial plasma glucose levels. The infarct size-reducing effect of voglibose was abolished by treatment with exendin(9-39), wortmannin, Nomega-nitro-L-arginine methylester, or 5-hydroxydecanoate), which inhibit GLP-1 receptors, phosphoinositide 3-kinase, nitric oxide synthase, and K(ATP) channels, respectively. Western blot analysis showed that treatment with voglibose upregulated myocardial levels of phospho-Akt, phosphoendothelial nitric oxide synthase after myocardial infarction. The upregulation of phospho-Akt was inhibited by exendin(9-39) and wortmannin. These findings suggest that voglibose reduces myocardial infarct size through stimulation of GLP-1 receptors, activation of the phosphoinositide 3-kinase-Akt-endothelial nitric oxide synthase pathways, and the opening of mitochondrial K(ATP) channels. These findings may provide new insight into therapeutic strategies for the treatment of patients with coronary artery disease.

A series of spiro[imidazolidine-4,4'(1'H)-quinazoline]- 2,2'5(3'H)-triones were prepared and tested for aldose reductase inhibitory activity. The 6'-halogenated derivatives were found to be highly potent in vitro inhibitors of male rabbit lens aldose reductase and in vivo inhibitors of polyol accumulation in the sciatic nerves of galactosemic rats. Of these, (4R)-6'-chloro-3'-methylspiro[imidazolidine-4,4'(1'H)-quinazoline] -2,2',5(3'H)-trione (67) showed the most potent in vitro and in vivo activities. An oral dose of 3 g/kg of compound 67 caused neither death nor behavioral abnormality in the preliminary acute toxicity study using mice and rats. Compound 67 was selected as a candidate for further evaluation. The quantitative structure-activity relationships in this series are also discussed.

Optically pure 3'-methylspiro[imidazolidine-4,4'(1'H)-quinazoline]-2,2',5(3'H-trione was prepared by optical resolution using brucine as a resolving agent. The resulting optically pure spirohydantoin was racemized by refluxing in 1,2-dichlorobenzene for 17 h, or more effectively upon heating in 10% HCl at 90 o C for 2 h. In the acid-catalyzed racemization, the introduction of difluoromethyl group at the 3-nitrogen of hydantoin ring increased the racemization rate, while the introduction of methyl group at the 3-nitrogen reduced it

The reaction of 1-carbamoylisatins 2 with 2-ethyl-2-isothiourea hydrobromide in the presence of triethylamine followed by acid-catalyzed cyclization of the resulting 4-(2-ethyl-2-isothioureido)carbonyl-3, 4-dihydro-4-hydroxy-2(1H)-quinazolinones 7 provides a general and high-yielding route to 3'-substituted spiro[imidazolidine-4, 4'(1'H)-quinazoline]-2, 2'5(3'H)-triones 8.

Reaction of 1-ethoxycarbonylisatin (1b) with urea gave 5-(2-ethoxycarbonylaminophenyl)-5-hydroxyhydantoin (4b) in a good yield. Treatment of 4b with several amines directly gave the corresponding spiro[imidazolidine-4, 4'(1'H)-quinazoline]-2, 2', 5(3'H)-trione derivatives (7a-d) in moderate yields. 3-Unsubstituted and 3-methylspiroquinazolin-2-one derivatives 7a, b were also synthesized from 5-ethoxy and 5-ethylthiohydantoins 5a, d, which in turn were easily obtained by the reaction of either ethanol or ethylmercaptan with 4b in the presence of a catalytic amount of sulfuric acid.

SummaryRats are employed to investigate the role of platelets in thrombus formation under flow conditions in vivo and to evaluate the pre-clinical potential of antiplatelet drugs. While Wistar and Sprague-Dawley (SD) strains are commonly used in thrombosis models, a number of rat strains have been established. Each strain possesses genetically unique characteristics such as hypertension, hyperglycemia or hyperlipidemia. The appropriate selection of a strain might have advantages for physiological and pharmacological studies. Comparative investigation of platelet aggregation among laboratory strains of rats is useful for the development of thrombosis models. In the present study, platelet aggregation response in eight laboratory rat strains, ACI, Brown Norway (BN), Donryu, Fischer 344 (F344), LEW, SD, Wistar and WKAH, were compared. Considerable strain differences were observed in ADP-, collagen- and TRAP-induced platelet aggregation. SD and BN are high-platelet-aggregation strains, while F344 and ACI are low-response strains. In the arteriovenous shunt thrombosis model, SD formed larger thrombi than F344 andWistar rats. In the FeCl 3 -induced thrombosis model with the carotid artery, the time to occlusion of SD was significantly shorter than of F344 and ACI rats. F344 and ACI rats had significantly increased bleeding times compared with SD rat. The present study demonstrates that there are considerable strain differences in platelet aggregation among laboratory rats, which reflect thrombus formation.

The purpose of this study was to investigate the morphological characteristics of lens fibers in albino and pigmented rats by scanning electron microscopy. In addition to the ubiquitous interdigitating edge protrusions many ball-and-socket junctions were found on the lateral surfaces of lens fibers in pigmented rats. Notable differences in density, shape and size between superficial and deep cortical layers were observed. Especially, in the intermediate equatorial cortex large ball-and-socket junctions were found. In contrast, only few and small ball-and-socket junctions were observed in albino rats and many ruptures of lens fiber membranes were present in the anterior, superficial and intermediate equatorial cortex. The present observations show that different strains of rats have a different morphology of lens fibers. In view of a postulated role of ball-and-socket junctions in calcium homeostasis in the lens this may account for differences in cataractogenesis between albino and pigmented rats.

The purpose of this study is to observe dynamic morphological changes induced by ultraviolet (UV) irradiation in a cultured human lens epithelial cell line using electron microscopy, cell viability staining, time-lapsed videography and immunohistochemistry. Human lens epithelial cell line SRA 01-04 was cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 20% fetal bovine serum. Subconfluent cells were irradiated under a bank of UV lamps, which emitted 275-400 nm radiation with a maximum at 310 nm. The UV intensity was 20 microW cm(-2)at dosages from 0 to 10 mJ cm(-2). Alterations in the morphology of the living cells were monitored and recorded with phase-contrast microscopy and time-lapsed videography. At different times, the cells were fixed and examined by transmission electron microscopy (TEM), diamidinophenolindole (DAPI) staining, and in situ immunohistochemistry using TdT-mediated dUTP-biotin nick end labeling (TUNEL). Cell viability was also assessed with crystal violet staining. At low doses of UV exposure (2-5 mJ cm(-2)), time-lapsed videography revealed definitive cell death that appeared to be primarily apoptotic. The dead cell debris was engulfed and phagocytosed by neighboring living cells. Phase-contrast microscopy and TEM demonstrated that, at UV 10 mJ cm(-2), the cells not only showed typical apoptosis such as nuclear membrane shrinkage, chromatin condensation, and fragmentation into apoptotic bodies, but also necrosis such as swelling of the nucleus and cell body, and disruption of the plasma membrane. In support, DNA staining and in situ immunohistochemical reactions in the UV irradiated cells were both positive. The phagocytotic process was also seen with TEM. UV irradiation thus appears to cause both apoptosis and necrosis in the cultured human lens epithelial cell line. Active migration and phagocytosis of the cells appear to be stimulated by UV-induced damage. These findings may also aid in the understanding of UV injury and repair mechanisms of lens epithelial cells in vivo.

Reaction of 1-methylcarbamoylisation (4) with urea in the presence of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) gave 4-hydroxy-3-methyl-4-ureidocarbonyl-1, 2, 3, 4-tetrahydroquinazolin-2-one (5), which was easily cyclized with 10% HCl to afford a spirohydantoin derivative; 3-methyl-spiro[1, 2, 3, 4-tetrahydroquinazoline-4, 4'-imidazolidine]-2, 2', 5'-trione (6). In a similar manner, 2'-imino-3-methyl-spiro[1, 2, 3, 4-tetrahydroquinazoline-4.4'-imidazolidine]-2, 5'-dione (8) was prepared by the reaction of 4 with guanidine, and 8 was further converted to the spirohydantoin compound 6 by treatment with sodium nitrite in acetic acid.

(S)-5-Iodonicotine (4a), an (S)-nicotine analog iodinated at the 5-position of the pyridine ring, was synthesized and evaluated as a potential radiopharmaceutical for investigating brain nicotine receptors by single photon emission computerized tomography (SPECT). [125I]-(S)-5-Iodonicotine ([125I]-4a) was synthesized by the iododestannylation reaction under no-carrier-added conditions and purified by high-performance liquid chromatography (HPLC). The binding affinity of 4a for brain nicotine receptors was measured in terms of displacement of [3H]cytisine from binding sites in rat cortical membranes. The binding data revealed that the affinity of 4a was the same as that of (S)-nicotine and 80-fold higher than that of the (R)-enantiomer (4b). Biodistribution studies in mice disclosed that the brain uptake of [l>I]-4a was rapid and profound. Regional cerebral distribution studies in rats by autoradiography disclosed that the accumulation of [125I]-4a was dense in the thalamus, intermediate in the cortex and striatum, and less marked in the cerebellum. Furthermore, the administration of (S)-nicotine reduced the uptake of [125I]-4a in the thalamus and resulted in a nearly identifal level of radioactivity in the cerebellum. [125I]-(R)-5-Iodonicotine ([125I]-4b) showed more rapid washout from the brain and a less extensive regional cerebral distribution than the (S)-enantiomer ([125I]-4a). Thus, 4a bound to brain nicotine receptors in vivo, and therefore iodine-123-labeled 4a may be a potential radioligand for use in in vivo cerebral nicotinic receptor studies by SPECT.

High reactivity of [11C]-methyl iodide ([11C]CH3I) with the thiol group was demonstrated with cysteamine and other compounds containing a thiol and another functional groups in each structure. The methylation of the thiol group in cysteamine with [11C]CH3I was very rapid at 0 degree C with no catalyst, and gave a high radiochemical yield and purity without any detectable by-product. Moreover, this reaction was not disturbed by the other functional groups, such as -NH2, -OH and -COOH in the same structure. This S-methylation reaction is very useful for producing a new radiopharmaceutical labeled with the short lived positron emitting nuclide C-11.

A nicotine agonist, 11C-labeled (S)-nicotine, was synthesized by N-methylation of (S)-nornicotine with [11C]-methyl iodide in dimethylformamide-dimethylsulfoxide in order to study nicotinic receptors in the human brain by positron emission tomography. The radiochemical yield of this N-methylation reaction was more than 90% within 5 min. After purification by high performance liquid chromatography the radiochemical purity of the product was more than 99% and the specific radioactivity was 7.4-11.1 GBq/mumol. The regional distribution of (S)-[11C]nicotine in the mouse brain after intravenous injection was compared with that of (R)-[11C]nicotine. After injection of (S)-[11C]nicotine, the regional uptake of radioactivity was in the following order: cortex greater than thalamu approximately hippocampus greater than striatum greater than hypothalamus greater than cerebellum. Moreover, (S)-[11C]nicotine was displaced from the brain by unlabeled (S)-nicotine, but unlabeled (R)-nicotine caused no change in uptake. In contrast, (R)-[11C]nicotine showed a lower brain uptake and lesser regional differences in radioactivity.

PURPOSE To clarify the process of acute lens epithelial cell photo-damage induced by ultraviolet B (UV-B) exposure and its repair. METHODS Pigmented rabbits were exposed to UV-B (300 mJ/cm2). The time course of lens epithelial cell photo-damage was evaluated by light microscopy of lens epithelial cell flat mounts. The flat mounted lens epithelial cells were stained with Mayer's hematoxylin or by immunohistochemistry with anti-proliferating cell nuclear antigen (PCNA) monoclonal antibodies. RESULTS The lens epithelial cells were irregularly arranged and there were debris and pycnotic nuclei, small nuclei, existence of large cells, and phagocytosis of neighboring cells in the pupillary area. A repair process was seen in the injured areas within a week after UV-B exposure. PCNA positive cells were seen and it was confirmed that the healing of the photo-injured part was due to epithelial cell proliferation. CONCLUSIONS The acute lens epithelial cell photo-damage induced by UV-B exposure was repaired within a week by cell proliferation.

1-Phenyl-4(1H)-quinazolinones having various substituents at C-2 were synthesized and some of their reactions were examined. 1-Phenyl-2-substituted-4(1H)) quinazolinones (3) were synthesized in good yield by the reaction of 2-phenylaminobenzamide (1) with excess acid chloride under mild reaction conditions. The 2-chloroalkyl derivatives (3b-d) react with nucleophiles in a characteristic manner depending on the length of the alkyl chain. Treatment of the 2-chloromethyl derivative (3b) with nucleophiles gave 2-(substituted-methyl)-4(1H)-quinazolinones (4). Reaction of 2-chloroethyl derivative (3c) with morpholine or alcohols gave 2-(β-substituted-ethyl) derivatives (5-7) through the intermediate (8), which was identified by isolation. Allowing a chloroform solution of the 2-(γ-chloropropyl) derivative (3d) to stand afforded the 4-oxoquinazolinium salt (9a) quantitatively.

Two novel ring systems, 12-methyl-6H-isoquino [2, 1-a] quinazolin-6-one (2) and 6-methyl-13H-quinazolino [3, 4-a] quinazolin-13-one (3a), were synthesized. Reaction of 3-methylisocoumarin (4) with 2-cyanoaniline gave 2-(2-cyanophenyl)-3-methylisocarbostyril (5), which was converted to 2-(2-carbamoylphenyl)-3-methylisocarbostyril (6) by treatment with alkaline hydrogen peroxide. The cyclization of 6 with boron trifluoride etherate afforded 2. Compound 3a was prepared by the reaction of 2-methyl-4H-3, 1-benzoxazin-4-one (8a) with 2-cyanoaniline in one step. Some derivatives (3b-g) were also prepared by this method. The reaction mechanism is discussed.

Seven main metabolites (3-9) of afloqualone (1, 6-amino-2-fluoromethyl-3-(o-tolyl)-4 (3H)-quinazolinone and related 4 (3H)-quinazolinone derivatives were synthesized. The metabolites 4 and 5 containing a sulfur atom were prepared by the reaction of 6-acetamido-2-chloromethyl-3-(o-tolyl)-4 (3H)-quinazolinone (11) with NaSCH3 followed by oxidation with H2O2. Reaction of 11 and N-acetyl-L-cysteine gave the mercapturic acid-conjugated metabolite 6. Condensation of 2-fluoroacetamido-5-nitrobenzoic acid (19) and 2-amino-benzyl alcohol (20) with dicyclohexylcarbodiimide (DCC) in the presence of 1-hydroxy-benzotriazole afforded 2-fluoromethyl-3-(o-hydroxymethylphenyl)-6-nitro-4 (3H)-quinazolinone (21), which was converted to the metabolites 7 and 8. Treatment of the 2-bromomethyl-4 (3H)-quinazolinone (24) with AgBF4-H2O in dimethylsulfoxide (DMSO) gave the 2-hydroxymethyl metabolite 9. None of the main metabolites (2-9) showed significant central nervous system depressant activity.

A number of new 4(1H)-quinazolinones were synthesized and evaluated in the carrageenin-induced paw edema test. Most of the compounds were obtained by the cyclization of the appropriately substituted anthranilamides with acid chlorides, followed by further chemical transformation. Structure-activity data suggest that 2-isopropyl-1-phenyl-, 2-cyclopropyl-1-phenyl-, and 1-isopropyl-2-phenyl-4(1H)-quinazolinones afford optimal potency and the presence of a halogen atom is preferred for activity. Adrenalectomy does not affect the antiinflammatory test results. The best result taking into account both efficacy and side effects was displayed by 1-isopropyl-(2-fluorophenyl)-4-(1H)-quinazolinone (50).

The mitochondria were prepared from apples cv. Starking Delicious which were sensitive to chilling injury and apples cv. Rails Janet which were not sensitive to chilling injury. The content of unsaturated fatty acids in the Rails Janet mitochondria was higher than that in the Starking Delicious mitochondria. Phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidic acid, phosphatidylserine, diphosphatidylglycerol (cardiolipin) and mono- and digalactosyldiglyceride were identified as the conjugated lipid components. The PC/PE ratios were 0.74 and 0.14, respectively, in the mitochondrial phospholipid fraction of Rails Janet and Starking Delicious apples. The higher ratio of PC/PE and unsaturated fatty acid contents in Rails Janet than those in Starking Delicious may cause the resistance to chilling injury in Rails Janet by playing a role in lowering of the phase transition temperature. These facts were thought to contribute largely to the flexibility, fluidity a...