• YAKHAK HOEJI
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• v.39 no.4
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• pp.438-443
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• 1995

Four different pseudopolymorphs of amoxicillin-trihydrate, dehydrate, monohydrate and anhydratewere prepared and characterized by UV spectrophotometry, DSC, and TGA. In vitro dissolution studies of four pseudopolymorphs were carried out in pH 6.8 phosphate buffer at $37^{\circ}C$ by means of a rotating disk method. The effect of four pseudopolymorphs on bioavauability of amoxicillin was studied in healthy 6 subjects using urinary excretion method. The dissolution result was shown in the sequence, trihydrate(95.5%)>monohydrate(83.5%)>anhydrate(67.6%)>dihydrate(15.8%). The urinary excretion rate of anhydrate could not be detected and the dissolution results agreed well with in vivo phannacoldnetic study results. The effects of storage conditions, milling and compression on the pseudopolymorpnc transformation were investigated by thermal methods. The results showed that four pseudopolymorphs were not transformed and they were very stable.

• Journal of fish pathology
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• v.23 no.3
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• pp.357-367
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• 2010

The pharmacokinetic properties of amoxicillin trihydrate (Amox) were studied after single oral administration and single intravenous injection to cultured eel, Anguilla japonica, respectively (average $220{\pm}10\;g$, $28{\pm}1^{\circ}C$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. The kinetic profile of absorption, distribution and elimination of Amox in plasma were analyzed fitting to a two-compartment model by WinNonlin program. In oral dosage of 40 and 80 mg/kg body weight, the peak plasma concentrations of Amox, which attained at 3~12 h post-dose, were 3.4 and $3.3\;{\mu}g/ml$, respectively. In intravenous injection with 1 mg/kg, the peak plasma concentrations of Amox, which attained at 9 h post-dose, was $7.2\;{\mu}g/ml$. The following parmeters were calculated for a single oral dosage of 40 and 80 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)= 464 and $667\;{\mu}g{\cdot}h/ml$; $T_{max}$ (time for maximum concentration)= 2.1 and 3.6 h; $C_{max}$ (maximum concentration)= 3.04 and $3.4\;{\mu}g/ml$. Following intravenous injection at 1 mg/kg, this parameters were AUC= $748\;{\mu}g{\cdot}h/ml$; $C_{max}=4.2\;{\mu}g/ml$. The apparent oral bioavailability at 40 and 80 mg/kg were 1.6 and 1.1%, respectively. Despite using the trihydrate form of amoxicillin, the oral bioavailability was low in eel.

• YAKHAK HOEJI
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• v.23 no.3_4
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• pp.133-140
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• 1979

The adsorption of erythrosine in the aliphatic alcohols by antibiotics such as ampicillin anhydrous, ampicillin trihydrate, amoxicillin trihydrate, cephalexin monohydrate was studied. The adsorption isotherms were all described with Freudlich equation. From the various experimerts, it was found that the adsorption of erythrosine by antibiotics in the aliphatic alcohols was affected by the solubility of adsorbents. The adsoption in the mixture of aliphatic alcohols and water is related with the dielectric constant of mixed solvents. According to increase in the pH values of aqueous solution, the adsorption of erythrosine for antibiotics is decreased, but increased in the mixture of aliphatic alcohols and water. The adsorption of erythrosine in the suspension of antibiotics showed a correlation with the temperature. Colloidal silica which is used as stabilizer had a favorable effect on the adsorption of erythrosine in the suspension of antibiotics.

• ALGAE
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• v.20 no.2
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• pp.121-125
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• 2005

The modern integrated fish-seaweed mariculture has been tested to reduce the environmental impacts of an intensive fed culture. To obtain the best seaweed bioremediation performance, the effects of therapeutants used for fish disease control on the selected seaweed species should be considered. As a selected seaweed, Porphyra yezoensis was tested with six commercial antibiotics including erythromycin thiocyanate_A, erythromycin thiocyanate_B, oxytetracycline, doxycycline, pefloxacin, and amoxicillin trihydrate under the batch incubation at a photon flux density of 10 $\mu$mol ${\cdot}m^{-2}\;{\cdot}\;s^{-1}$ at 15$^{\circ}C$. Among the tested commercial antibiotics, erythromycin thiocyanate_A, erythromycin thiocyanate_B, oxytetracycline, and doxycycline showed decreases in Fv/Fm, the photochemical efficiency of photosystem II, with a dose-dependant and time-dependant manner. From the quenching analysis of chlorophyll fluorescence, three differential patterns were observed in the antibiotics-treated Porphyra: (1) high nonphotochemical quenching (NPQ) and low photochemical quenching (qP) in the cases of Erythromycin thiocyanate_B and amoxicillin trihydrate, (2) high NPQ and high qP in the case of pefloxacin and (3) low NPQ and low qP in the case of oxytetracycline. These results indicated that antibiotics affected in various ways on the photosynthetic apparatus, reflecting differential lesion sites of antibiotics. In addition, the rates of ammonium uptake also decreased with a decrease of Fv/Fm in P. yezoensis thalli treated with erythromycin thiocyanate_B and oxytetracycline. Therefore, the four antibiotics mentioned could affect the bioremediation capacity of the selected seaweed species in the integrated fish-seaweed mariculture system due to the decrease of photosynthetic activity and the simultaneous decrease of ammonium uptake.

• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.242-244
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• 2003

A 3-year-old, male, mongrel dog was presented with pruritus, alopecia to the Veterinary medical Teaching Hospital, College of Veterinary Medicine of Kyungpook National University. On physical examination, generalized erythema, papules, scales and crusts were observed. The canine scabies infestation was diagnosed by deep skin scraping and Malassezia spp. and Staphylococcus spp. were found on skin cytology. He was treated with selamectin at 6 mg/kg applied to the skin in a single spot every two weeks for one month in order to investigate the effect of selamectin on canine scabies and was treated with amoxicillin trihydrate/clavulanate pattassium, ketoconazole and chlorhexidine shampoo for Malassezia sup. and Staphylococcus spp. simultaneously. When he was rechecked after 7, 14, 21, and 28 days after the first application of selamectin, scabies werent seen. The dermatological signs including pruritus, papules, scales, and crusts were remarkably resolved at 14 days. The alopecia was almost disappeared and few Malassezia spp. and Staphylococcus spp. were seen after 28 days. The efficacy of selamectin by this protocol is excellent in the dog infestated canine scabies.