Effects of vesnarinone, a novel orally active inotropic agent with an immunosuppressive action, on experimental cardiac transplantation in rats

BACKGROUND: Vesnarinone (VES) has been used for treatment of patients with congestive heart failure. In addition to inotropic effects, it seems to have immunosuppressive action. We tested the hypothesis that VES suppresses graft rejection, inotropic dysfunction caused by early rejection, and chronic coronary obstruction in a heterotopic rat cardiac transplantation model. METHODS: (1) To study acute rejection, hearts from Lewis-Brown Norway (LBN) rats were transplanted into Lewis rats, which were treated with or without VES (50 or 100 mg/kg/day orally). (2) In a functional study, LBN hearts with or without VES (100 mg/kg/ day) were isolated and perfused on day 3 after transplantation to assess inotropic response to isoproterenol (3 x 10(-8) M). (3) To study chronic rejection, Lewis hearts were transplanted into Fisher 344 rats, which were treated with or without VES (50 mg/kg/day) for 90 days. Coronary obstructive disease was assessed by morphometric analysis. There were five to six animals in each group. RESULTS: (1) VES (100 mg/kg/day) prolonged LBN heart survival (11.7 +/- 0.7 vs. 9.6 +/- 0.7 days in control; P < 0.05). (2) Left ventricular developed pressure was depressed in transplanted hearts regardless of VES treatment (84 +/- 12, 90 +/- 8 vs. 144 +/- 16 mmHg in untransplanted hearts; P < 0.01). The developed pressure after administration of isoproterenol in VES-treated hearts (184 +/- 20 mmHg) was higher than transplanted hearts without VES (118 +/- 16 mmHg; P < 0.05), and similar to untransplanted hearts (203 +/- 27 mmHg; P = NS). (3) Transplanted hearts treated with or without VES showed similar grades of rejection (2.0 +/- 0.3 vs. 2.6 +/- 0.2; P = NS), intimal area (6,996 +/- 3,186 vs. 13,441 +/- 5,165 microns2; NS), and coronary luminal obstruction (45 +/- 16% vs. 67 +/- 14%; NS). CONCLUSIONS: VES produces mild prolongation in survival of rat heart grafts, but has no significant effect on chronic graft atherosclerosis. VES preserves the positive inotropic effects of isoproterenol that are otherwise deteriorated by early acute rejection.     

Endoscopic treatment of vesicoureteral reflux in patients with myelodysplasia

PURPOSE: We assessed the usefulness of and indications for endoscopic treatment of vesicoureteral reflux in myelodysplasia patients. MATERIALS AND METHODS: A total of 26 patients treated with intermittent catheterization was divided into 11 (16 ureters) with and 15 without vesicoureteral reflux. In 9 patients (13 ureters) endoscopic correction was performed with 3% atelo-collagen and without anesthesia at the outpatient clinic. In each ureter we obtained the sum of scores for 4 risk factors for upper urinary tract deterioration: bladder compliance less than 10 ml./cm. water, grade 2 to 3 bladder deformity, detrusor-sphincter dyssynergia and urethral closure pressure 50 cm. water or greater. RESULTS: No reflux was demonstrated immediately after the initial collagen injection but cystography 3 to 6 months later showed recurrent reflux in 5 ureters (38%). Repeat injection cured the reflux, with results persisting for an average of 17 months. Mean risk factor score for patients without vesicoureteral reflux was significantly lower than that for patients with reflux. In patients treated with intermittent catheterization and anticholinergic agents the mean score for ureters with an increased or unchanged reflux grade was significantly greater than for those with a decreased grade. CONCLUSIONS: Endoscopic treatment of reflux appears to be safe and useful in patients with myelodysplasia. The treatment is preferable in those with high risk factor scores due to the possibility of increased reflux grade in such patients.     

Robust parameter-estimation using the bootstrap method for the2-parameter Weibull distribution

This paper proposes bootstrap robust estimation methods for the Weibull parameters; it applies bootstrap estimators of order statistics to the parametric estimation procedure. Estimates of the Weibull parameters are equivalent to the estimates using the extreme value distribution. Therefore, the bootstrap estimators of order statistics for the parameters of the extreme value distribution are examined. Accuracy and robustness for outliers are examined by Monte Carlo experiments which indicate adequate efficiency of the proposed reliability estimators for data with some outliers     

Crosslinking of amidated polybutadiene with resole. I

Various liquid polybutadiene derivatives were examined as modifiers to improve the brittleness of phenolic resins. Amidated polybutadienes obtained from a maleinated polybutadiene and ammonia had the highest curing tendency when they were reacted with resole under mild conditions. The cured resins were homogeneous and the brittleness of the phenolic resins was remarkably improved. Crosslinking efficiency was closely related to the succinamic acid group of the amidated polybutadiene. Thermal behavior of the succinamic acid group was also related to the effects of curing temperature and curing time on crosslinking. From these observations, cross-condensation between the succinamic acid group of an amidated polybutadiene and resole seemed to have occurred to a great extent than the self-condensation of resole itself and oxidative crosslinking of the amidated polybutadiene.     

Flexible generation mix under multi objectives and uncertainties

Criteria for evaluating flexibility of a generation mix are presented, and an efficient computational algorithm for determining a flexible generation mix considering uncertainties in the power system expansion planning is developed. The flexible generation mix problem is formulated as a multiobjective optimization problem and solved by the dynamic programming technique in which type of generation plant is selected as a stage and generation capacity is selected as a state. The proposed method can treat easily not only the uncertainties but also many constraints of generation planning such as integer solutions of generation capacities, reliability constraints, and so on. The effectiveness and feasibility of the proposed method are demonstrated on a typical power system model     

Determination of horseradish peroxidase concentration using the chemiluminescence of Cypridina luciferin analogue, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazin-3-one

The chemiluminescence of the Cypridina luciferin analogue, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazin++ +-3-one (MCLA) was observed at 462 nm in the presence of horseradish peroxidase (HRP) and the total spectrum of light emitted was found to depend linearly on HRP concentration. Methods for the determination of HRP concentration using the chemiluminescence was investigated. HRP could be detected in the range from 100 pmol/L to 100 nmol/L under the optimum condition, H2O2 (10 mmol/L) and MCLA (10 mumol/L) at pH 5.8.     

Pseudo-binary system Bi2O3-TeO2 in air

The phase equilibria in the pseudo-binary system Bi₂O₃-TeO₂ at 600° 950° C in air were examined by solid-state reaction techniques and X-ray powder diffraction method. Four pseudo-binary compounds appeared, i.e., -Bi₂O₃ type solid solution having a compositional range of (1-x)Bi₂O₃·xTeO₂ wherex=0 0.4 a new compound Bi₆Te₂O₁₅ which has an orthorhombic cell of a=2.27(4) nm, b=1.06(1) nm and c = 0.539(8) nm, 2Bi₂O₃ · 3TeO₂, and an unidentified phase Bi₂O₃·2TeO₂. The formation of the phase Bi₆Te₂O₁₅, in which all the Te ions are hexavalent, was confirmed by the thermogravimetry and by the Mössbauer spectra. The liquidus curves for whole system were determined by DTA method.     

X-ray CDF study on the behaviour of the amorphous chain under extension

The behaviour of the amorphous chain in vulcanized natural rubber (NR) and styrene-butadiene rubber (SBR) under extension is studied by means of the cylindrical distribution function (CDF) derived from wide angle X-ray scattering (WAXS). In the case of the highly stretched vulcanized NR where the orientation-induced crystallization took place, the observed WAXS intensity was separated into a crystalline peak component and a broad amorphous one from which the CDF was obtained. The CDF calculated from the broad component shows that some of the amorphous segments of the highly stretched vulcanized NR are extended as fully as the crystalline chains and that the fraction of the segments increases with increasing extension. In the case of SBR, such fully stretched segments as in the case of the vulcanized NR show higher degree of an interchain packing order than those in the vulcanized NR.     

Molecular association complex of urea with polyethylene: 3. Structural studies of the complex

The crystal structure of urea-polyethylene complex in the hexagonal form, obtained by one of our preparation methods, is analysed by X-ray power diffractometry. In this analysis, the fixed molecular parameters of urea are used, and three models with respect to rotational disorder of the guest polyethylene molecule are assumed. It is shown that the host lattice structure constructed by urea molecules is essentially the same as that of urea-n-paraffin complex. Effects of the disorder structure of the guest on X-ray scattering of the complex are presented. However, there is a difficulty in identifying the disorder structure by X-ray analysis. With the aid of a potential energy calculation between the hexagonal urea tunnel and the guest molecule, a rotational disorder model is preferred.     

Electron-microscopic procedure for acrylic rubber

The electron-microscopic visualization of acrylic rubber dispersed in a heterogeneous structural resin composition consisting of a rubber-modified two-phase plastic comprising essentially a butyl acrylate rubber phase and an acrylonitrile–styrene copolymer phase, respectively, has been accomplished. This procedure consists of the following: The molded resin specimen is treated with hydrazine hydrate solution to produce the acrylic acid hydrazides. Allow the treated specimen to soak in osmium tetroxide solution. The acrylic rubber may be indirectly fixed and stained. Some micrographs of ultrathin sections of two or three resin compositions, cut by an ultramicrotome, are presented.