Comparison of the effects of the novel vasodilator FK409 with those of nitroglycerin in isolated coronary artery of the dog.

1. The vasorelaxant effects of FK409, a new nitrovasodilator synthesized from a microbial product, were compared with those of nitroglycerin in isolated coronary artery rings of the dog contracted with U46619 (10(-7) M). 2. FK409 (10(-11)-10(-5) M) and nitroglycerin (10(-9)-10(-4) M) each produced a concentration-dependent relaxation. Comparison of EC50 values showed that FK409 was about 25 times more potent than nitroglycerin. 3. Submaximum concentrations of nitroglycerin (10(-6) M) and FK409 (3 x 10(-8) M) elevated guanosine 3':5'-cyclic monophosphate (cyclic GMP) levels, effects associated with vasorelaxation. Adenosine 3':5'-cyclic monophosphate (cyclic AMP) levels were unaffected. 4. The concentration-relaxation curves for nitroglycerin and FK409 were shifted to the right by methylene blue (3 x 10(-6) - 3 x 10(-5) M), an inhibitor of soluble guanylate cyclase, and to the left by M&B22,948 (3 x 10(-6) - 3 x 10(-5) M), an inhibitor of cyclic GMP phosphodiesterase. 5. After exposure of coronary arteries to the maximally-effective concentration of nitroglycerin (10(-4) M), the mean EC50 value of FK409 did not change significantly, although that of nitroglycerin increased about 60 fold. After exposure to the maximally-effective concentration of FK409 (10(-5) M), the mean EC50 value of FK409 increased about 6 fold and that of nitroglycerin about 11 fold. 6. These results suggest that the vasorelaxant effect of FK409, like that of nitroglycerin, is due to activation of soluble guanylate cyclase and a resultant increase in intracellular cyclic GMP. However, compared with nitroglycerin, there was less self-tolerance to the relaxant effects of FK409 and relatively little cross-tolerance between the two agents.     

Influence of composition and purity on tensile properties of Ni-Ti alloy castings.

The influence of composition and purity of titanium on the mechanical properties and the transformation temperatures of Ni-Ti alloy dental castings was investigated by tensile testing and differential scanning calorimetry (DSC). The compositions of the ingots were 49.0-49.2 at% of titanium content. Three grades of titanium of relatively high purity were used as starting materials. The result showed Ni-49.0Ti to be a somewhat brittle property, and Ni-49.2Ti to have low apparent proof strength and large elongation. Residual strain increased with increasing titanium content. Even small reductions of titanium purity influenced the tensile properties and the transformation temperatures, causing high apparent proof strength, low residual strain and low elongation because of the reduction in transformation temperatures.     

Adsorption and desorption of aclarubicin into and from activated carbon particles as drug carrier--an in vitro study

A new dosage form (ACR-CH), aclarubicin(ACR) adsorbed on activated carbon particles (CH), was studied for adsorption and desorption onto and from CH. The adsorption isotherm at 37 degrees C in saline and phosphate buffer (pH 7.4-7.5) were shown as M = 175 Co.15 and M = 207 Co.24, respectively (M = ACR amount adsorbed on CH, microgram/mg; C = ACR concentration in a free state, microgram/ml). In both fluids, CH adsorbed more than 100-1,000 times more amount of ACR than ACR in a free state. ACR-CH was lavaged 7 times and the released ACR in a free state was measured. The results showed that ACR-CH desorbed constantly a small amount of ACR, namely, 1.5-8 percent of initial concentration of ACR in a free state in saline, 0.1-10% in phosphate buffer, and 0.5-4.0% in Ringer's solution. Under the same conditions, desorption of ACR-CH was measured in dog's blood plasma. The first lavage made ACR-CH desorb at 25.7 +/- 0.85 percent of ACR initial concentration in a free state, and two times' to 7 times' lavage made 1-3%. Overall, 43.3 +/- 0.99% of ACR were desorbed from the activated carbon. It was concluded that ACR-CH slowly released a constant amount of ACR for a long period.     

Probing depth, attachment loss and gingival recession

The present investigation describes probing pocket depth, probing attachment level and recession data from 319 randomly selected subjects, aged 20-79 years, from Ushiku, Japan. The findings are reported as mean values, frequency distributions and percentile plots of the 3 parameters at buccal, interproximal and lingual surfaces of single rooted (incisors, canines, premolars) and molar teeth. Inter-as well as intra-examiner errors for probing pocket depth and probing attachment levels were assessed and found to be small. The data reported revealed that practically all subjects studied had one or more sites in the dentition affected by destructive periodontal disease and that the severity of disease increased with age. It was further observed that in each age group, molars had suffered more attachment loss than single rooted teeth and that the interproximal surfaces as a rule had lost more periodontal tissue support than corresponding buccal and lingual surfaces. The attachment loss difference observed between different surfaces of a given tooth or a group of teeth, however, was comparatively small. In the age groups between 20-59 years, advanced destructive periodontal disease was found in a small subgroup of the subject sample, while after the age of 60 years, widespread destructive periodontitis was common. An attempt was made to examine the progression of destructive disease with age by comparing the frequency distributions of sites with attachment loss of greater than or equal to 3 mm in subjects of different age groups. The data suggested that in younger subject groups, progression was confined to a subset of individuals, while in older age groups, more subjects and sites became involved. A major feature of destructive periodontal disease in older individuals was the accompaniment of attachment loss with recession at the gingival margin. Deep pockets were relatively infrequently detected, while advanced loss of attachment (with recession) occurred at many sites.     

Irreversible in vivo binding of thiabendazole to macromolecules in pregnant mice and its relation to teratogenicity

The binding of [14C]thiabendazole ([14C]TBZ) to macromolecules in the liver, foetus and other tissues was investigated in Jcl:ICR mice on day 13 of gestation. TBZ suspended in olive oil was given orally in a dose of 1 g/kg body weight (5 microCi/mouse) and the mice (in groups of three) were killed 0.5, 1, 3, 6, 24 and 96 hr later. The bound radioactivity in the liver and foetus was at a maximum between 3 and 24 hr after treatment. The rate of decrease of the bound radioactivity was slower than that of total radioactivity. Bound radioactivity was also present in other tissues (including kidney, lung, heart, placenta and spleen). The level of bound radioactivity was measured in the liver and foetuses after oral administration of teratogenic doses of 200-1600 mg/kg. Disproportionate increases in bound radioactivity were observed in both tissues after administration of the highest dose.     

The maternal-foetal distribution of thiabendazole administered in two different vehicles to pregnant mice

We have compared the effects of two vehicles on the maternal-foetal distribution of 14C-thiabendazole ([14C]TBZ) given orally to Jcl: ICR mice on day 9 or 16 of gestation. TBZ, either suspended in olive oil (TBZ-O) or in a 0.5% aqueous solution of gum arabic (TBZ-G), was given orally on day 9 of gestation at a dose of 1 g/kg body weight (1 microCi/mouse). The mice were killed 0.5, 1, 3, 6, 12, 24 or 72 hr later. In mice treated with TBZ-O maximum levels of radioactivity in plasma and conceptuses were observed at 0.5 hr, whereas in those treated with TBZ-G maximum 14C levels were observed at 6 hr. The uptake of radioactivity from TBZ-O into the plasma and conceptuses was significantly higher than that from TBZ-G. Only trace levels of radioactivity were detected at 72 hr in both treatment groups. The placental transfer of [14C]TBZ was examined in mice treated with doses of 1 g/kg body weight (1 microCi/mouse) given as TBZ-O or TBZ-G on day 16 of gestation. The radioactivity in foetuses, placentas and maternal plasma was higher in mice treated with TBZ-O than those given TBZ-G. The placental transfer of [14C]TBZ was also examined by whole-body autoradiography in mice treated on day 16 of gestation.     

Single vaginal ectopic ureter via Gartner's duct cyst spontaneously perforating into the bladder

We report on a girl with a rare variant of single vaginal ectopic ureter via Gartner's duct cyst, which ruptured spontaneously into the bladder leading to aggravation of urinary incontinence. The patient also had a megalovagina, and a fistula between the distal urethra and vagina. She became continent after removal of a dysplastic kidney, unroofing of the cyst and closure of the fistulas.