Biomedical subjects

Hong Kim

Publications and source records attributed to Hong Kim.

47 records · Page 3Linked to original sources

PubMed2003

Effects of Paeonia radix on 5-hydroxytryptamine synthesis and tryptophan hydroxylase expression in the dorsal raphe of exercised rats.

Paeonia radix is the root of Paeonia japonica MIYABE, a perennial plant classified in the family Paeoniaceae. In the present study, the effects of Paeonia radix on performance in treadmill exercise, and 5-hydroxytryptamine (5-HT) synthesis and tryptophan hydroxylase (TPH) expression in the dorsal raphe were investigated. Time to exhaustion in treadmill exercise was increased and exercise-induced increases in 5-HT synthesis and TPH expression in the dorsal raphe were shown to be suppressed by Paeonia radix treatment; 5-HT synthesis and TPH expression were inhibited by Paeonia radix treatment under resting conditions as well. In sum, treatment with Paeonia radix, inhibiting 5-HT synthesis and TPH expression, may bring about reduced fatigue, both during exercise and the resting state.

Animals↗

PubMed2003

Folium mori increases cell proliferation and neuropeptide Y expression in dentate gyrus of streptozotocin-induced diabetic rats.

The possibility has been raised that Folium mori is clinically effective for the treatment and prevention of diabetes. In the present study, the effects of Folium mori on cell proliferation and expression of neuropeptide Y (NPY) in the dentate gyrus of rats with streptozotocin (STZ)-induced diabetes were investigated by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and NPY immunohistochemistry. In rats with STZ-induced diabetes, cell proliferation and NPY expression in the dentate gyrus were suppressed, and treatment with Folium mori was shown to increase new cell formation and NPY expression in the dentate gyrus in both normal rats and those with STZ-induced diabetes. In light of previous studies, this result appears to indicate that increased expression of NPY in the dentate gyrus induced by treatment with Folium mori is associated with the observed effect of Folium mori extract on cell proliferation. Based on the present results, it is suggested that Folium mori treatment may aid in the recovery from the central nervous system complications of diabetes mellitus.

Animals↗

PubMed2002

Treadmill running and swimming increase cell proliferation in the hippocampal dentate gyrus of rats.

The effects of treadmill exercise and swimming on cell proliferation in the dentate gyrus and the involvement of opioid receptors were investigated via 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. Sprague-Dawley rats of the running groups were made to run on treadmill for 30 min each day, while those of the swimming groups were made to swim for 5 min each day over 3 consecutive days. In addition, intensity-dependency of the effects of running and swimming on cell proliferation was investigated. The present results demonstrate that both treadmill running and swimming increase the number of BrdU-labeled cells in the dentate gyrus and these increasing effects are more potent in light intensity and 5 min swimming groups. Treatment with naloxone increases cell proliferation in the dentate gyrus in all groups, although this increase is statistically insignificant.

Animals↗

PubMed2002

Effects of acupuncture on the 5-hydroxytryptamine synthesis and tryptophan hydroxylase expression in the dorsal raphe of exercised rats.

In the present study, the effects of acupuncture on the endurance treadmill exercise, serotonin (5-hydroxytryptamine, 5-HT) synthesis, and tryptophan hydroxylase (TPH) expression in the dorsal raphe nuclei were investigated. Acupunctural stimulation were bilaterally inserted into the locus of Zusanli in each hind leg for 20 min. Onset of exhaustion time on the treadmill running was increased significantly by acupunctural stimulation and exercise-induced increments of the 5-HT synthesis and TPH expression in the dorsal raphe were suppressed by acupunctural stimulation. Based on the results, it can be suggested that the suppressive effects of acupunctural stimulation on the 5-HT synthesis and TPH expression in the dorsal raphe during exercise is one of ergogenic mechanisms of acupuncture.

Acupuncture Therapy↗

PubMed2002

Alcohol and nicotine administration inhibits serotonin synthesis and tryptophan hydroxylase expression in dorsal and median raphe of young rats.

Serotonin (5-hydroxytryptamine, 5-HT) has been implicated in the pathophysiology of various neuropsychiatric disorders. In the present study, the effects of alcohol and nicotine on the synthesis of 5-HT and the expression of tryptophan hydroxylase (TPH), the rate-limiting enzyme of 5-HT synthesis, in the dorsal and median raphe of young rats were investigated via immunohistochemistry. The numbers of the 5-HT-positive and TPH-positive cells were reduced by alcohol and nicotine treatment in a dose-dependent manner. Based on the results, it can be suggested that the pathogenesis of alcohol- and nicotine-induced neuropsychological disorders involves alcohol- and nicotine-induced suppression of 5-HT synthesis and TPH expression in raphe, and that this may be of particular relevance in the consumption of alcohol and nicotine during adolescence.

Aging↗

PubMed2002

Hypothermia inhibits cell proliferation and nitric oxide synthase expression in rats.

In the present study, the effects of cold-water immersion on cell proliferation and nitric oxide synthase expression in the dentate gyrus of rats were investigated. Sprague-Dawley rats were divided into four groups: the control-rest group; the control-heat group; the cold-rest group; and the cold-heat group. Cold-water immersion for 5 min at 4 degrees C suppressed the numbers of 5-bromo-2'-deoxyuridine-positive and nicotinamide adenine dinucleotide phosphate-diaphorase-positive cells in the dentate gyrus, and these numbers were increased by warming for 30 min at 30 degrees C. In the present study, it was demonstrated that warming protects against cold stress-induced suppression of new cell formation, and results suggest that nitric oxide, the synthesis of which is affected adversely by cold-water immersion, may play an important role in the regulation of cell proliferation.

Animals↗

PubMed2002

Pharmacokinetics of the active antifungal enantiomer, SCH 42427 (RR), and evaluation of its chiral inversion in animals following its oral administration and the oral administration of its racemate genaconazole (RR/SS).

Genaconazole (SCH 39304) is a potent triazole antifungal agent that is active both orally and topically. Genaconazole is a racemic mixture which contains 50% of the RR (SCH 42427) and 50% of the SS (SCH 42426) enantiomers. The RR isomer accounts for most of the antifungal activity of genaconazole. Serum concentrations of the RR and SS enantiomers were analyzed by a chiral HPLC method which involved extraction of serum with organic solvent followed by separation on a Cyclobond I column and quantification by UV absorbance at 205 nm. The bioavailability and pharmacokinetic profiles of the two enantiomers after oral administration of the racemate (genaconazole) were very similar in cynomolgus monkeys. In rats following dosing with genaconazole, the RR enantiomer had a lower C(max) and a longer t(1/2) than the SS enantiomer, while the AUC(I) values of the two enantiomers were similar. Based on chiral HPLC analysis, there was no evidence for the inversion of the RR to the SR isomer, or of the SS to the SR isomer, indicating that there was no chiral inversion of the RR or SS enantiomers in either species. Genaconazole at 20 mg/kg and the RR (SCH 42427) enantiomer at 10 mg/kg had very similar serum concentration-time profiles and C(max), AUC(I), and t(1/2) values for the RR enantiomer in both rats and monkeys, indicating that the two treatments were equivalent with respect to the bioavailability of the RR enantiomer.

Administration, Oral↗

PubMed2002

Simultaneous high-performance liquid chromatographic determination of SCH 59884 (phosphate ester prodrug of SCH 56592), SCH 207962 and SCH 56592 in dog plasma.

SCH 59884 is an IV prodrug of SCH 56592, the broad-spectrum azole antifungal agent that is active both orally and intravenously in animal models of infection. SCH 56592 is in phase III clinical trials for the treatment of serious systemic fungal infections. SCH 59884 is a carboxylate ester of SCH 56592 with gamma-butyric acid phosphate. Following IV administration of SCH 59884, the compound is rapidly dephosphorylated to SCH 207962 which is then hydrolyzed to SCH 56592. A high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of SCH 59884, SCH 207962 and SCH 56592 in plasma of dogs, a species used for safety evaluation. The HPLC analysis involved protein precipitation with methanol followed by separation on a C-18 column and quantitation by UV absorbance at 260 nm. The lower limits of quantification were 0.1 microg/ml for SCH 59884 and 0.05 microg/ml for SCH 207962 and SCH 56592 in dog plasma. The linearity for the three compounds was satisfactory as indicated by correlation coefficients (r) of >0.98, back-calculated concentrations and visual examination of the calibration curves. The precision and accuracy were satisfactory as shown by coefficients of variation (CV) ranging from 2.4 to 10.6%, and bias values ranging from -8.4 to 13.3%. Moreover, SCH 59884 and SCH 207962 were stable in dog plasma after being subjected to three freeze-thaw cycles. SCH 56592 had been shown earlier to be stable under these conditions. The assay was shown to be specific, accurate, precise, and reliable for use in pharmacokinetic and toxicokinetic studies.

Animals↗

PubMed2002

Ginseng radix increases cell proliferation in dentate gyrus of rats with streptozotocin-induced diabetes.

In the present study, the effect of Ginseng radix on cell proliferation in the dentate gyrus of rats with streptozotocin-induced diabetes was investigated via immunohistochemistry. Aqueous extract of Ginseng radix was shown to exert no significant effect on weight in normal rats, while it prevented weight loss in rats with streptozotocin-induced diabetes. Cell proliferation in the dentate gyrus of diabetic rats was increased by Ginseng radix treatment, but it had no effect on cell proliferation in normal rats. These results suggest that Ginseng radix may help in improve the central nervous system complications of diabetes mellitus.

Animals↗

PubMed2002

Administration of Folium mori extract decreases nitric oxide synthase expression in the hypothalamus of streptozotocin-induced diabetic rats.

Folium mori, the leaves of Morus alba L., has traditionally been used for the treatment of diabetic hyperglycemia. It has been shown to induce enhanced NOS expression in the hypothalamus of rats with streptozotocin (STZ)-induced diabetes. In the present study, the effect of Folium mori on the expression of nitric oxide synthase (NOS) in the hypothalamus of STZ-induced diabetic rats was investigated via nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Enhanced NAPDH-d expression was detected in the paraventricular nucleus, ventromedial hypothalamic nucleus, and lateral hypothalamic area of the hypothalamus in the STZ-induced diabetes group. Administration of the aqueous extract of Folium mori to rats with STZ-induced diabetes resulted in decreased NADPH-d positivity. These results suggest that Folium mori treatment is effective in curbing the desire for food under diabetic conditions via modulation of NO expression in the hypothalamus.

Animals↗

PubMedDate not supplied

Risk factor for extrahepatic bile duct cancer in patients with anomalous pancreaticobiliary ductal union.

BACKGROUND/AIMS: Anomalous connection between the choledochus and pancreatic duct is considered to be a factor in the development of biliary tract diseases such as choledochal cyst, pancreatitis, cholangitis, gallbladder cancer, and bile duct cancer. Our purpose was analysis of combined disease, especially biliary neoplasm and evaluated microscopic changes of extrahepatic bile ducts. METHODOLOGY: To study the clinical characteristics of anomalous pancreaticobiliary ductal union (APBDU), we reviewed 14 APBDU cases from June 1994 to June 1998. We studied the associated disease, surgical treatment, and the histological findings of the extrahepatic bile ducts. RESULTS: Gallbladder cancer was identified in 5 out of 14 patients with APBDU. The incidences of metaplasia of gallbladder and bile duct with APBDU were higher than that of control gallbladder epithelium. The proliferating cell nuclear antigen-labeling index of the gallbladder in patients with APBDU was significantly higher than that in the control group. CONCLUSIONS: The patients with APBDU showed high incidence of gallbladder carcinoma and metaplasia in epithelium of gallbladder and bile duct. As this metaplasia in the gallbladder and bile duct is thought of as a precancerous condition, it is important to remove the place that causes bile stasis and to stop backflow of pancreatic juice into the bile duct in managing patients with this anomaly. In other words, prophylactic cholecystectomy and reconstruction of the biliary tract are both necessary.

Abnormalities, Multiple↗