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Effect of water extract of Danshen on bone regeneration of rat calvarial defect model
2010
Shim, K.M., Nambu University, Gwangju, Republic of Korea | Kim, S.E., Chonnam National University, Gwangju, Republic of Korea | Kang, S.S., Chonnam National University, Gwangju, Republic of Korea
The purpose of this study was to evaluate the osteogenic capacity of water extract of danshen (Salvia miltiorrhiza Bunge). We have established in rat critical-sized calvarial defect model using the combination with collagen scaffold and danshen hydrophilic extract. All rats were extinguished at 8 weeks after bone graft surgery, and the bone regeneration ability of bone grafting sides was evaluated by plain radiography and micro-CT. These results revealed water extract of danshen had the potential to promote osteogenesis especially continuous oral administration with local treatment compared to one-shot local treatment. This compound may provide a new alternative agent for growth factors to promote bone healing and bone regeneration. In conclusion, these results suggest that danshen hydrophilic extract have the potential to promote osteogenesis in bone defects. Further studies about fusion technology with salvianolic acid B, peptides, growth factors, and scaffolds using of the combination of tissue engineering, cell engineering and mechanical engineering are needed.
Show more [+] Less [-]An anatomical study on the branching patterns of left coronary artery in the rats
2007
Ahn, D.C. (Kangwon National University, Chuncheon, Republic of Korea) | Kim, I.S. (Chonbuk National University, Jeonju, Republic of Korea), E-mail: iskim@chonbuk.ac.kr
The left main descending artery (LMDA) of left coronary artery (LCA) in rats runs around the left side of conus arteriosus after arising from the aortic sinus and descends to the apex of heart with branching several branches into the wall of left ventricle (LV). The ligation site of LMDA for myocardial infarction (MI) is the 2~4 mm from LCA origin, between the pulmonary trunk and left auricle. The characteristics that rat heart has no interventricular groove on the surface and its coronary arteries run intramyocardially with branching several branches give the difficulty in surgery for MI which resulted in expected size.
Show more [+] Less [-]Hematological and blood chemical findings in hypophysectomized rats
2005
Kim, N.J. (Hyechon College, Daejeon, Republic of Korea), E-mail: njkim@hcc.ac.kr | Kim, M.C. (Chungnam National University, Daejeon, Republic of Korea)
The present study was carried out to produce the hematological and blood chemical findings after hypophysectomy in rats. Hypophysectomy was performed by the parapharyngeal method and the sham surgery was performed for the control group. Two weeks after the operation, the body weight of the hypophysectomized and control rats was measured daily for 5 days. We deleted the rats the weight gain of which is less than 5 g during 5 days from the hypophysectomy group. The successful operation rate was approximately 40%. In the hypophysectomized and control rats, their blood samples were collected from posterior vena cava after celiotomy under generally anesthesia with ether.
Show more [+] Less [-]Histological effect of cyclophosphamide on diethylnitrosamine-induced hepatic tumors in rats
1999
Kwak, S.D. | Kang, C.B. | Koh, P.O. | Kim, C.S. (Gyeongsang National University, Chinju (Korea Republic). Institute of Animal Medicine, College of Veterinary Medicine)
This study was designed to evaluate the effect of cyclophospaide(CY) on dietynitrosamine(DEN)-induced hepatic tumors in rats. Thirty five male of femal Sprague Dawley rats were continiously given water containing O.01% DEN for 10 weeks and then were give with CY 25mg/rat/day in water for 3, 5, 7 or 9 days. The livers of rats were removed and fixed in 10% buffered neutral formalin. The appearances of positive cells by immunohistochemical methods using proliferating cell nuclear antigen (PCNA) antibody, p53 antibody and apoptotic kit were investigated. The livers of rats given with CY were grossly brilliant, red-brown color, flexible, and thin border, and stainability of the liver cells were restored microscopically, and the vaccuolated and degenerated regions were differentiated from restored regions. These restored findings also were advanced in control group becouse of no DEN treatment but tended to be less avanced. In immunohistochemistry, positive cells to PCNA antibody appeared more numerous in control groups than that of CY treated groups. Appearance of positive cells in CY-treated group for 7 days and for 9 days were more numerous than those of CY-treated groups for 3 days and for 5 days, respectively. So these findings suggested that CY suppressed cell proliferations and effects of these action were decreased with CY-treated days. The numbers of positive cells to PCNA antibody were more prominent in hepatocelular carcinoma regions and cholangiocarcinoma regions, and then were ranked as order of large liver cell regions and normal liver cell regions. Also the numbers of the positive cells by apoptotic kit tended to be higher in hepatocelular carcinoma regions and cholangiocarcinoma regions but not uniformly in order in all regions nd were much less numbers than those of OCNA positive cells. So immunohistochemical methods using PCNA antibody together than using apoptotic kit alone when anti-carcinogen experiments. Rats with positive cells by p53 antibody were 11 of 15 rats(73.4%) in control groups and 12 of 18 rats(66.7%) in CY treated group, respectively. These positive cells appeared focally in early vacuole-occurring regions and were low in numbers.
Show more [+] Less [-]Therapeutic effects of 1alpha,25 dihydroxycholecalciferol on osteoporotic fracture in a rat model
1999
Bae, C.S. (Konkuk University, Seoul (Korea republic). Department of Surgery, Faculty of Veterinary Medicine)
Osteoporosis is defined as a decrease in bone mass that leads to an increased risk of fracture. The therapeutic effect of 1alpha,25 dihydroxycholecalciferol, the hormonal form of vitamin D3 that mediates calcium translation in intestine and bone, on the healing process of fracture has still been controversial. These studies were designed to understand the healing process of normal fibular fracture, the osteoporotic changes after ovariectomy, and the theraqeutic effects of 1alpha,25 dihydroxycholecalciferol on the osteoporotic fracture in rats. The simple transverse fractures of rat fibulae were produced with a rotating diamond saw. The changes of the biochemical and mechanical indices of rats were investigated. The mechanical study based on bending test revealed the healing of the fibular fracture in the 5th week after simple transverse fracture. The osteoporosis impaired more the healing of osteoporotic fibular fracture than normal non-osteoporotic fibular fracture. The healing process of osteoporotic fracture was facilitated by the treatment with 1alpha,25 dihydroxycholecalciferol, however was delayed more than the healing process of normal fracture. The bone strength based on the bending test also confirmed this tendency. The bone strengths in the 5th week after fracture of normal bone, osteoporotic bone, and 1alpha,25 dihydroxycholecalciferol-treated osteoporotic bone were 75%, 41% and 67%, respectively, in comparison with those of intact bone. In conclusion, 1alpha,25 dihydroxycholecalciferol was effective in promoting the osteroporotic fracture healing.
Show more [+] Less [-]Effects of diazepam on fetal development in rats
1999
Kim, C.J. | Kim, Y.J. | Yu, I.J. (Chonbuk National University, Chonju (Korea Republic). Department of Obstetrics, College of Veterinary Medicine)
To investigate the effect of diazepam on fetal development in pregnant rats, this experiment was performed in eighty Sprague-Dawley female rats which were 8 weeks old and grouped into two according to different diazepam treatment period during 5-9 days of gestation and 10-14 days of gestation. Both experimental groups were included by saline treated groups (control) and diazepam-treated groups (6mg, 12mg and 24mg), respectively. Diazepam was injected to pregnant rats subcutaneously, which were wacrified on 20 days of gestation and mean litter size, fetal body weight, fetal crown-rump length (CRL) and pathological findings were examined. 1. Concerning mean litter size, diazepam-treated groups showed lower mean litter size than control in both 5-9 days and 10-14 days of gestation groups(p0.05) without difference according to dosage of diazepam and day of gestation. 2. Concerning fetal body weight, diazepam-treated groups during 5-9 days of gestation showed lower fetal body weight than control and the other treated group during 10-14 days(p0.01) without difference according to dosage of diazepam. Diazepam-treated group during 10-14 days of gestation showed no difference among experimented groups. 3. Concerning fetal crown-rump length (CRL), diazepam-treated groups during 5-9 days of gestation showed shorter CRL than control and the other treated group during 10-14 days of gestation(p0.01) without difference according to dosage of diazepam. 4. Reduction of mean litter size, fetal body weight and CRL was shown from when treated by the dosage of 6mg/kg of diazepam. 5. Maternal mortality according to dosage of the 20mg/kg of diazepam were 30% and 20% in the treated group during 5-9 days and 10-14 days of gestation, respectively. These results indicated that diazepam treatment in pregnant rats caused considerable reduction of mean litter size, fetal body weight and fetal crown-rump length when treated during 5-9 days of gestation.
Show more [+] Less [-]Inhibitory effect of propofol on endothelium-dependent relaxation and blood pressure lowering in rats
Kim, S.J.;Kim, J.G.;Joe, S.G.;Kang, H.S.;Kim, J.S.(Chonbuk National University, Jeonju, Republic of Korea)E-mail:kimjs@chonbuk.ac.kr
We studied the effect of propofol (PPF) on the endothelium-dependent vascular responses in isolated rat thoracic aorta. In aortic rings with endothelium, PPF inhibited the phenylephrine (PE)-induced contraction in a concentration-dependent manner. In PE-precontracted preparations, PPF attenuated the endothelium-dependent relaxation by acetylcholine but not by A23187. And PPF did not attenuate the endothelium-independent relaxation by sodium nitroprusside (SNP).
Show more [+] Less [-]Inhibitory effects of xylamine on the arterial contraction in rats
Kim, S.J.;Kang, H.S.;Kim, J.S.(Chonbuk National University, Jeonju, Republic of Korea)E-mail:kimjs@chonbuk.ac.kr
The therapeutic efficacy of xylamine in the field of psychological medicine has been recognized for years and the drug is used to treat depression and some other conditions, but little is known about its mechanism of action on vascular system. Therefore, the present study was designed to investigate the influence of xylamine on the contractile responses of isolated rat thoracic arteries to phenylephrine(PE) and potassium chloride(KCl). Xylamine produced a concentration-dependent relaxation in PE-precontracted endothelium intact(+E) rat aortic rings, but not in a KCl-precontracted aortic rings.
Show more [+] Less [-]Pre- and postnatal development study of amitraz in rats
2010
Kim, S.H., Chonnam National University, Gwangju, Republic of Korea | Lim, J.H., Chonnam National University, Gwangju, Republic of Korea | Park, N.H., Chonnam National University, Gwangju, Republic of Korea | Moon, C.J., Chonnam National University, Gwangju, Republic of Korea | Park, S.H., Chonnam National University, Gwangju, Republic of Korea | Kang, S.S., Chonnam National University, Gwangju, Republic of Korea | Bae, C.S., Chonnam National University, Gwangju, Republic of Korea | Kim, S.H., Chonnam National University, Gwangju, Republic of Korea | Shin, D.H., Chonnam National University, Gwangju, Republic of Korea | Kim, J.C., Chonnam National University, Gwangju, Republic of Korea
This study investigated the potential effects of amitraz on the pre- and postnatal development, behavior, and reproductive performance of offspring of parent rats given amitraz during pre-mating, gestation, and lactation. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and lactation up to weaning. Based on fluid consumption, the male rats received an average of 0, 5.7 ± 1.33, 13.2 ± 2.08, and 35.8 ± 3.42 mg/kg/day amitraz, and the female rats received an average of 0, 8.7 ± 4.42, 20.1 ± 9.60, and 47.6 ± 22.38 mg/kg/day amitraz, respectively. At 360 ppm, an increase in the incidence of abnormal clinical signs, a suppression in the body weight gain, a decrease in the food consumption and litter size, an increase in the post-implantation loss, and a decrease in the seminal vesicle weight were observed in the parent animals. In addition, a suppression in the body weight gain, a decrease in the grip strength, a delay in the negative geotaxis, an increase in the pre- and post-implantation loss, and a decrease in the number of live embryos were observed in the offspring. At 120 ppm, suppressed body weight gain and reduced food consumption were observed in the parent rats. Suppressed body weight gain and decreased grip strength were also observed in the offspring. There were no signs of either reproductive or developmental toxicity at 40 ppm. Under these experimental conditions, the no-observed-adverse-effect level of amitraz for parent rats and their offspring was estimated to be 40 ppm in rats.
Show more [+] Less [-]The evaluation on the biological safety of diagnostic ultrasound using radiation-induced apoptosis in the external granular layer of mouse cerebellum
1999
Oh, H. | Lee, S.E. | Yang, J.A. | Chung, C.Y. | Son, C.H. | Kim, S.H. (Chonnam National University, Kwangju (Korea Republic). College of Veterinary Medicine) | Jo, S.K. (Korea Atomic Energy Research Institute, Taejon (Korea Republic). Department of Food Irradiation)
We have studied, by a nonisotopic in situ end-laveling(ISEL) technique, frequency of apoptosis in the external granular layer(EGL) of the cerebellum of immature mice by Y-rays irradiation from 60Co or diagnostic ultrasound exposure. The total number of normal cells and cells showing morphological features of apoptosis were counted. The frequency of apoptotic cells was expressed as a percentage of the total number of cells in EGL. The extent of changes following 200 cGy(1090 cGy/min) was studied at 2, 4, 6, 8, 12, or 24 hours after exposure. The maximal frequency was found 6~8 hours after exposure. The immature mice that received 18, 36, 54, 108, 198, 396, cGY of y-rays or diagnostic ultrasound(7.5MHz, 4.2mW, Ispta=7.9mW/cm2, Ispta=114.3W/cm2) for 10 or 30 minutes were examined 6 hours after irradiation. Measurements performed after y-ray irradiation showed a dose-related increase in apoptotic cells in each of the mice studied. The dose-response curves were analyzed by a linear-quadratic model;frequency of apoptotic cell in the EGL was y=(0.1349+_0.01175)D+(-0.0001522+_0.0000334)D2+0.048(r2=0.981, D-dose in cGy). In the experiment of ultrasound exposure, the frequency of apoptotic cell was 0.106+_0.130(10 minutes exposure) and 0.167+_0.220(30 minutes exposure). We estimated the relative dose of the yield from the experiment with ultrasound by substituting the yield from ultrasound exposure into the curve from the y-irradiation. The relative dose of ultrasound exposure compared with y-irradiation were 0.432 cGY(10 minutes exposure) and 0.885 cGY(30 minutes exposure). We have found that there is no evidence to indicate that diagnostic ultrasound involves a significant risk.
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