• Journal of Periodontal and Implant Science
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• v.53 no.6
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• pp.467-477
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• 2023

Purpose: The purpose of this study was to evaluate the regenerative capacity of stem cells combined with bone graft material and a collagen matrix in rabbit calvarial defect models according to the type and form of the scaffolds, which included type I collagen matrix and synthetic bone. Methods: Mesenchymal stem cells (MSCs) were obtained from the periosteum of participants. Four symmetrical 6-mm-diameter circular defects were made in New Zealand white rabbits using a trephine drill. The defects were grafted with (1) group 1: synthetic bone (β-tricalcium phosphate/hydroxyapatite [β-TCP/HA]) and 1×10⁵ MSCs; (2) group 2: collagen matrix and 1×10⁵ MSCs; (3) group 3: β-TCP/HA, collagen matrix covering β-TCP/HA, and 1×10⁵ MSCs; or (4) group 4: β-TCP/HA, chipped collagen matrix mixed with β-TCP/HA, and 1×10⁵ MSCs. Cellular viability and cell migration rates were analyzed. Results: Uneventful healing was achieved in all areas where the defects were made at 4 weeks, and no signs of infection were identified during the healing period or at the time of retrieval. New bone formation was more evident in groups 3 and 4 than in the other groups. A densitometric analysis of the calvarium at 8 weeks post-surgery showed the highest values in group 3. Conclusions: This study showed that the highest regeneration was found when the stem cells were applied to synthetic bone along with a collagen matrix.

• Archives of Plastic Surgery
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• v.34 no.3
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• pp.298-304
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• 2007

Purpose: This study was undertaken to investigate the osteogenic induction potential of PGA & FBS mixture on a calvarial defect in the rabbit. Methods: Twenty New zealand white rabbit, weighing from 3.5-4kg were allocated into each of the three groups. Four 8 mm sized bone defects were made on the parietal bone by drilling. In group I, the bony defects were implanted with $50{\mu}m$ thickness film containing mixture of PGA and FBS. In group II, with PGA only film, & in group III, the bony defects were left with no implants. Results were evaluated by using morphologic change, radiographic study, biochemical study and histologic examination at 1 week (group I n=7, group II n=7, group III n=14), 2 weeks (group I n=6, group II n=6, group III n=12) and 3 weeks (group I n=7, group II n=7, group III n=14) following implantation. Results: In the morphologic & radiographic study, the formation and corticalization of callus were observed earlier in group I than in groups II and III (p < 0.05). In histological examination, group I showed more abundant and faster new bone formation than in group II and III. In biochemical analysis, group I displayed more activity than in group II and III. Group I also showed more abundant osteopontin, osteocalcin than groups II and III. Conclusion: In conclusion, the results demonstrate that the mixture of PGA and FBS has an effect on osteoblastic formation in the rabbit model. It is considered that further evaluation of long term results on resorption, immunologic tissue reaction and response of applied mixture in the human model will be needed.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.6
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• pp.466-472
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• 2010

Introduction: This study examined the effect of recombinant human bone morphogenetic protein (rhBMP)-2 and $\beta$-tricalcium phosphate ($\beta$-TCP) on new bone formation in a rabbit calvarium using a rapid prototype titanium cap (RP Ti cap). Materials and Methods: Eight New Zealand white rabbits were used in this study. Hemispherical RP Ti caps (10 mm in diameter) were implanted subperiosteally on the rabbit calvaria. $\beta$-TCP was filled in the RP Ti cap in the control group, and rhBMP-2 soaked $\beta$-TCP was used in experimental group. The rabbits were sacrificed 2 and 4 weeks after the operation. The volume and pattern of newly formed bone was analyzed by micro computed tomography (CT). Results: Macroscopically, there were no abnormal findings in any of the animals. The micro CT images revealed new bone from the calvaria that expanded gradually toward the top of the titanium cap, particularly along the inner surface of the titanium cap in the experimental group at 4 weeks after grafting. There was no significant difference in new bone volume ratio between the control and experimental groups at 2 weeks after grafting. There was a statistically significant difference in the new bone volume ratio between the experimental ($14.1{\pm}1.8\;%$) and control ($7.2{\pm}1.5\;%$) groups at 4 weeks after grafting (P<0.01). Conclusion: The RP Ti cap can effectively guide new bone formation and rhBMP-2 can induce the new bone formation.

• Journal of Veterinary Clinics
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• v.20 no.2
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• pp.198-206
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• 2003

The purpose of the present study was to investigate the effect of polyphosphate on healing of skin wound in rabbits. Four skin wounds of 8mm in diameter were induced bilaterally(4 wounds/rabbit) on the dorsolateral aspect of the trunk of 15 male New Zealand white rabbits. Ten percent polyphosphate(poly P) type 25, 10% poly P type 35, 10% poly P type 25+10% poly P type 35 and 0.85% sterile saline solution were applied on the wound area and examined grossly and histopathologically. The rate of wound contraction and histopathological changes after poly P application on the skin wound were investigated. In gross findings, the wound contraction rates of 10% poly P 25 group were significantly decreased from day 2 to day 7 after operation than those of 0.85% sterile saline solution treated group (p < 0.01). Although the hemorrhage and inflammation were observed on days 3, 6 and 9 after operation in all groups, but in 10% poly P 25 was gradually decreased. Revascularization and reepithelialization were seen 3, 6 and 9 days after operation in all groups, especially in 10% poly P 25 was formed completely on 9 days. Fibroplasia were seen 3. 6 and 9 days after operation in all groups, especially in 10% poly P 25 was compact than other groups on 9 days. The results suggested that polyphosphate, especially 10% poly P 25 would be effective on healing of skin wound in rabbits through decrease of would contraction rate, increase of revascularization, reepithelialization and fibroplasia.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.683-689
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• 1995

임상적으로 건강한 New Zealand White 종인 수컷 토끼에서 항생제 norfloxacin(NFX)의 체내 동태를 조사하기 위하여 체중 kg당 5mg을 정맥 및 경구 투여하였다. 그 결과 빠른 분포기와 소실기를 갖는 2-콤파트먼트 모델 양상으로 나타났다. 혈장에서의 약물분석은 HPLC로 실시하였는데, 이동상은 acetonitrile/0.01M phosphate buffer/ 10% citric acid 1mM heptane sulfonic acid(10/70/20)이었고, 흡수 파장은 274nm에서 실시하였다. 정맥 투여후, 생물학적 반감기는 3.14시간으로 나타났으며, 분포반감기는 0.38시간으로 빠른 분포를 보여주었다. 최고 혈중농도는 $24.27{\mu}g/ml$로 계산되었으며 청소율은 0.68ml/kg/h로 분석되었다. 경구 투여후, 최고 혈중 농도와 최고 혈중 도달 시간은 $0.86{\mu}g/ml$과 0.43시간으로 각각 계산되었다. 이때의 생물학적 반감기는 3.61시간으로 정맥 투여시와 유의성 있는 차이는 없었으며, 흡수 반감기는 0.17시간으로 빠른 흡수를 보여주었다. 생체이용율은 30%로 나타났으며, 0.2-1.6g/ml인 치료혈중 농도 범위에서 혈장 결합율은 26%로 나타나, 토끼에서 항생요법은 구강 투여시 초기 투여량은 2.71mg/kg이며, 유지 투여량은 12시간마다 2.54mg/kg이 적당한 것으로 분석되었다.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.6
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• pp.874-878
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• 2013

Unlike Europe (particularly, Italy and Spain), where a number of studies have been conducted on the stressful effects of transport on rabbit welfare, few studies have been conducted on transportation of rabbits under hot, humid tropical conditions experienced in countries like Malaysia. We studied the effects of transportation in hot humid tropical conditions of Malaysia on physiometabolic changes in New Zealand white rabbits. Eighty experimental animals were divided into two groups of 40 bucks each and transported for either 3 or 1 h. Transportation caused a significant upsurge of aspartate aminotransferase, alanine aminotransferase and creatine kinase activities (p<0.001) though did not significantly affect lactate dehydrogenase (LDH) activity (p = 0.0706). Both transportation periods caused elevation in plasma glucose levels, lactic acidosis and dehydration as evidenced through elevated packed cell volume and plasma protein concentration. It was concluded that regardless of the duration, transport of rabbits under hot humid tropical conditions, resulted in heat distress since the rabbits showed hyperglycemia, hypercalcemia, lactacidemia, lymphocytopenia, dehydration and increase in blood enzyme activities.

• The Journal of Pediatrics of Korean Medicine
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• v.24 no.1
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• pp.117-125
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• 2010

Objectives The purpose of this study is to examine the effect of chondrocyte re-differentiation in using ukmijihwang-Tang gamibang aqua-acupuncture. Methods In this study, chondrocytes were extracted from New Zealand white rabbit's knee joint, and cultured in monolayer after collagenase treatment. In the third passage, after the mRNA transcript of the type II collagen significantly reduced, diluted Yukmijihwang-Tang gamibang were added to cultured of chondrocyte, and its effect on the mRNA expression of type II collagen was quantitatively evaluated. Results As a result of treatment with Yukmijihwang-Tang gamibang in vitro for 48 hours, the mRNA expression of type II collagen was up-regulated. In addition, the result of H&E-staining in vivo indicated that chondrocyte-like tissues were formed in repairing injured cartilages after 12 weeks of treatment with Yukmijihwang-Tang gamibang. Conclusions These results indicated that Yukmijihwang-Tang gamibang was effective on the recovery of chondrocyte phenotype, and could be used for cartilage regeneration in arthritic diseases. However, more clinical study of Oriental medical treatment for this case might be also needed.

• The Korean Journal of Physiology
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• v.25 no.1
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• pp.81-85
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• 1991

At the fifth day after right lung pneumonectomy in New-Zealand white rabbits $(0.8{\sim}1.1\;kg\;B.W.)$, phospholipid and protein concentration in the left lung lavage fluid were measured for clarification of the effect of unilateral pneumonectomy on the secretory function of the type II pneumocytes in growing rabbits. In an attempt to evaluate the effect of unilateral pneumonectomy on the compensatory growth of the residual lung, left lung weight and left lung weight-body weight ratio and DNA concentration, RNA/DNA and total DNA content in the left lung tissue were measured in pneumonectomized and in sham operated control rabbits. The lung weight of pneumonectomized rabbit was approximately two times heavier than that of the control rabbits. DNA concentration and RNA/DNA of the lung tissue were not changed but total DNA content was increased significantly. Phospholipid concentration in the lung lavage fluid of the pneumonectomized rabbits was over two times higher than that of control rabbits. from these experimental results, It is concluded that unilateral pneumonectomy in growing rabbits might cause to increase the secretion of pulmonary surfactant from type II pneumocyte of the residual lung. The cellular hyperplasia seems to be the primary response of the compensatory growing lung in unilateral pneumonectomized growing rabbits.

• Biomolecules & Therapeutics
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• v.9 no.4
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• pp.311-317
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• 2001

YHB6211, a newly developed recombinant human granulocyte colonystimulating factor, was administered at dose levels of 0, 3, 15, and 75 $\mu$g/kg/day intravenously to the pregnant New Zealand White rabbits (20 rabbits per group) during the organogenetic period, days 6 to 18 of gestation. All dams were subjected to Caesarian section on day 28 of gestation and their fetuses were examined for external, visceral, and skeletal abnormalities. No abnormalities in clinical signs, body weight changes, gross findings, mortality, and external appearance were found in all dams and fetuses exposed to 0, 3, and 15 $\mu$g/kg/day of YHB6211. However, in the group treated with 75 $\mu\textrm{g}$/kg/day of YHB6211, maternal body and uterine weights, fetal body weights and length, and the number of live fetuses were significantly decreased and further fetal mortality was remarkably increased. It is suggested that YHB6211 may have no side effect up to the dose level of 15 $\mu$g/kg/day, and there would be no teratogenicity for fetuses of rabbits up to 75 $\mu\textrm{g}$/kg/day even if it may have some toxic effects over 75$\mu\textrm{g}$/kg/day for dams and fetuses of rabbits.

• Korean Journal of Veterinary Research
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• v.39 no.1
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• pp.204-212
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• 1999

The visceral dissemination of Borrelia burgdorferi in New Zealand White rabbits was evaluated following intradermal inoculation of $1{\times}10^8$ spirochetes. We inoculated Borrelia burgdorferi B31, B garinii KW1 and B afzehlii S13, respectively, and monitored the dissemination in the experimentally infected rabbits for 28 days. In the B burgdorferi B31-challenged group, the spirochetes were completely cleared in rabbits at day 1 and visceral dissemination was not demonstrated. However, B garinii KW1 and B afzelii S13 were found to successfully disseminate in visceral organs of rabbits during the experiment period of 28 days. And experimentally infection-derived immunological responses in rabbits were identified with enzyme-linked immunosorbent assay and immunoblot analysis. Based on these results, the differences in the virulence of Lyme borrelial strains were proved in rabbit model.