• Korean Journal of Weed Science
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• v.7 no.3
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• pp.329-336
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• 1987

Antagonistic interaction between glyphosate and some herbicides in effects of post-emergence application on cut grass and of pre-emergence application on some weed species including barnyardgrass was evaluated with pots in plastic house. By addition of oxyfluorfen to glyphosate, the weeding efficacy on cutgrass was visually evaluated as promotive in both weeding rate and efficacy. However, by alachlor, simazine, gluphosinate or quizalofop-ethyl showed delayed weeding rate, and by paraquat, the promotive in rate but lower in efficacy, respectively. Fresh weights of cutgrass at 30 days after the lower-rate application has generally indicated the lower weeding efficacy than that from glyphosate alone. Even at higher rate application, the addition of alachlor or simazine to glyphosate has still indicated the lower efficacies. As a result of interaction analysis by Colby method, no synergism was detected from any treatments, and the combinations of simazine or paraquat to glyphosate in lower mixing rate showed significant antagonism at 5% probability level of DMRT. On the annual weed species including barnyardgrass, the significant soil-residual weeding efficacies were recognized by addition of any rate of oxyfluorfen, alachlor, simazine and higher rate of quizalofop-ethyl to glyphosate, respectively.

• Korean Journal of Weed Science
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• v.3 no.2
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• pp.208-222
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• 1983

To control ideally the weeds in orchards and systematize the utility of herbicides, the mixing effect of oxyfluorfen and paraquat was evaluated. Combinations of oxyfluorfen with paraquat were increased the control efficacies at any treatment without giving damage to fruit trees and appeared a synergism. The control effects were reduced from 80-90% to 40-60% as the time advanced. However, the relative synergistic index was higher at 60 days after treatment in preemergence treatment and at 90 days after treatment in early and late postemergence treatment, respectively. Also the index was relatively higher at lower dosage of both herbicides.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.188-193
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• 1984

Interactions of herbicide mixtures were assessed for effective control of annual and perennial paddy weeds by isobole method(90% control) using Echinochloa crusgalli Beauv. var. oryzicola Ohwi, Scirpus hotarui Ohwi, Sagittaria pygrnaea Miquel, and Cyperus serotinus Rottb which are dominated in the paddy field of Korea. Mixture of butachlor and pyrazolate showed additive effect for control of E. crusgalli Beauv. var. oryzicola Ohwi, S. hotarui Ohwi and C. serotinus Rottb, but synergistic effect for control of S. pygmaea Miquel. Interaction of bifenox and bromobutamide showed synergistic effect to E. crusgalli Beauv. var oryzicola Ohwi and C. Serotinus Rottb, but slightly antagonistic effect to S. pygmaeo Miquel.

• Journal of Pharmaceutical Investigation
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• v.10 no.3
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• pp.20-26
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• 1980

The purpose of this paper was to study the effect of sulpyrin on the absorption, excretion, metabolism, and protein binding of ampicillin in the small intestine of the rats and rabbits. The results are as follows; The absorption of ampicillin in small intestine of rats was increased by the combination of sulpyrin and ampicillin. The blood level of ampicillin in rabbits was elevated by oral administration of sulpyrin. The bioavailability of ampicillin was increased by simultaneous administration of sulpyrin and ampicillin. The urinary excretion of ampicillin was slightly decreased by combined administration of sulpyrin. The blood level of ampicillin was decreased and the urinary excretion was increased by long term administration of sulpyrin. On the other hand, metabolising enzyme of ampicillin was influenced by long term administration of sulpyrin. Protein binding rate of ampicillin was decreased by combination of sulpyrin as compared with control.

• Journal of Pharmaceutical Investigation
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• v.18 no.2
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• pp.89-97
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• 1988

A series of novel water-soluble paracyclophanes containing two diphenyl ether skeletons and two bridging aliphatic chains of various length were designed and prepared to develop artificial host compounds which might provide efficient hydrophobic field. They were 1,5,19,23-tetraaza-12,30-dioxa[5,1.5.1] paracyclophane (6), 1,6,20,25-tetraaza-13,32-dioxa[6.1.6.1]paracyclophane (7), 1,7,21,27-tetraaza-14,34-dioxa[7.1.7.1]paracyclophane (8) and 1,8,22,29-tetraaza-15,36-dioxa[8.1.8.1]paracyclophane (9). As the corresponding acyclic analogue, 4,4'-dimethylaminodiphenyl ether (11) was synthesized for the comparative study of further host-guest interaction.

• Journal of Pharmaceutical Investigation
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• v.27 no.1
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• pp.51-56
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• 1997

This study was attempted to investigate the pharmacokinetic interaction of vancomycin (10 mg/kg, i.v.) and probenecid (7.5. 15, and 30 mg/kg, oral) in rabbits. The area under curve (AUC) of plasma vancomycin concentration was significantly increased (p<0.01) in rabbits when the probenecid was coadministrated. Volume of distribution (Vd) was significantly decreased (p<0.05) in rabbits coadministrated with probenecid (15 and 30 mg/kg) and total body clearance (CLt) was decreased significantly (p<0.05. p<0.01) in rabbits coadministrated with probenecid (7.5, 15 and 30 mg/kg). There was significant correlation between AUC and probenecid dose. From the results of this experiment, it is desirable to adjust dosage regimen of vancomycin for reduction of side or toxic effect when the probenecid is coadministered in clinical practice.

• Journal of Pharmaceutical Investigation
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• v.26 no.2
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• pp.119-124
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• 1996

To develop oral controlled release dosage forms, ionic interactions between polymers and drugs were evaluated. Hydroxypropylmethyl cellulose and carboxymethylene were used as model nonionic and ionic polymers, respectively. 5-fluorouracil, propranolol-HCl and sodium salicylate were selected as model nonionic, cationic and anionic, respectively. Polymer-drug mixtures were compressed into tablets and drug release kinetics from these tablets were determined. Drug release from the tablets made of the nonionic polymer was not affected by the charge of drugs, rather, was regulated by the solubility of drugs in different pH releasing media. However, drug release kinetics were significantly affected when drug-polymer ionic interactions exist. Enhanced drug release was observed from anionic drug-anionic polymer tablets due to ionic repulsion, whereas drug release was retarded in cationic drug-anionic polymer tablets owing to ionic attractive force. Therefore, the results suggested that the polymer-drug interactions are important factors in designing controlled release dosage forms.

• Journal of Pharmaceutical Investigation
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• v.20 no.1
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• pp.1-5
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• 1990

Effect of an angiotensin inhibitor (AAS; loading dose of 25, 50, $100{\mu}g/kg$ and maintenance dose of 12.5, 25,$50{\mu}g/ka/hr$) on the pharmacokinetics of propranolol (4 mg/kg i.v.) was studied in rabbits. Plasma concentrations and relative bioavailability of propranolal increased upto 127-175% by AAS coinjection. The urinary excretion of propranolol decreased by AAS. Dosage regimen of propranolol should be adjusted when it is administered with AAS.

• Journal of Pharmaceutical Investigation
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• v.17 no.1
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• pp.15-21
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• 1987

Effects of phenobarbital pretreatment on the pharmacokinetics of enterohepatic recirculating griseofulvin were investigated by comparing normal to bile duct cannulated rats and also the effects of enhanced endogeneous bile flow on the absorption of griseofulvin were studied by means of in situ recirculation method in phenobarbital-pretreated rats. Phenobarbital was administered orally for five days at the dose of 75 mg/kg/day. The influence of phenobarbital pretreatment on the absorption rate constant, area under the plasma concentration-time curve, maximum plasma concentration of orally administered griseofulvin was not found in bile duct cannulated rats. Decreased absorption clearance and apparent partition coefficient of griseofulvin in accordance with the amount of endogeneous bile juice seemed to be due to the decrease of thermodynamic activity of griseofulvin as bile forms the micelle with griseofulvin.

• Journal of Pharmaceutical Investigation
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• v.14 no.4
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• pp.183-188
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• 1984

The interactions of FD & C Red No.3 (erythrosine) in 1 or 2% concentrations with various types of pharmaceutical gelatins were studied. In visible region spectroscopy type A gelatin showed 6 nm bathochromic shift in ${\lambda}_{max}$ of erythrosine, but no shifts were observed in other gelatins. Various results were obtained in the decrease of absorbance from 0.06 to 0.25. In dissolution study, the gelatin that showed the greatest spectral change exhibited the worst profile. From above results, it is concluded that erythrosine interacted to the greatest extent with type A gelatin and in the case of type B gelatin the degree of the interaction in different according to their specifications.