• Journal of Animal Science and Technology
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• 제64권1호
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• pp.52-69
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• 2022

Ferulic acid (FA) is a phytochemical with various bioactive properties. It has recently been proposed that due to its phytogenic action it can be used as an alternative growth promoter additive to synthetic compounds. The objective of the present study was to evaluate the growth performance, carcass traits, fiber characterization and skeletal muscle gene expression on hair-lambs supplemented with two doses of FA. Thirty-two male lambs (n = 8 per treatment) were individually housed during a 32 d feeding trial to evaluate the effect of FA (300 and 600 mg d^-1) or zilpaterol hydrochloride (ZH; 6 mg d^-1) on growth performance, and then slaughtered to evaluate the effects on carcass traits, and muscle fibers morphometry from Longissimus thoracis (LT) and mRNA abundance of β₂-adrenergic receptor (β₂-AR), MHC-I, MHC-IIX and IGF-I genes. FA increased final weight and average daily gain with respect to non-supplemented animals (p < 0.05). The ZH supplementation increased LT muscle area, with respect to FA doses and control (p < 0.05). Cross-sectional area (CSA) of oxidative fibers was larger with FA doses and ZH (p < 0.05). Feeding ZH increased mRNA abundance for β₂-AR compared to FA and control (p < 0.05), and expression of MHC-I was affected by FA doses and ZH (p < 0.05). Overall, FA supplementation of male hair lambs enhanced productive variables due to skeletal muscle hypertrophy caused by MHC-I up-regulation. Results suggest that FA has the potential like a growth promoter in lambs.

• 대한수의학회지
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• 제37권2호
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• pp.281-289
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• 1997

The study was designed to investigate the effects of progesterone and estrogen on the uterus of rats by immunohistochemical methods using Proliferating Cell Nuclear Antigen (PCNA) antibody. Eighteen female rats(Wistar), weighing initially about 300g, were ovariectomized. These rats were divided into four groups, progesterone-treated group, estrogen-treated group, estrogen+progesterone-treated group, and control group, progesterone-treated group was injected with 1mg of progesterone per rat per day for 2 days and estrogen-treated group with $20{\mu}g$ of $17{\beta}-estradiol$ for 3 days and estrogen+progesterone-treated group with $17{\beta}-estrdiol$ for 3 days and then with progesterone for 2 days as above. In gross findings, the uteri were markedly hypertrophied by estrogen treatment but were not affect in size by progesterone treatment. Immunohistochemical investigation was performed on the cell types with higher appearance of PCNA positive reaction cells in four groups. The groups with higher appearance of the stromal cells were ordered as estrogen-treated group, progesterone-treated group, estrogen+progesterone-treated group, and control group. The muscle cells were ordered as progesterone-treated group, estrogen-treated group, estrogen+progesterone-treated group, and control group. Positive reaction cells of the stromal cells were total 4.6 times higher than those of muscle cells. Therefore, the affect of the hypertrophy on the uterus by estrogen was larger than those of progesterone and affect on the uterus by stromal cells were larger than those of muscle cells. The group with more PCNA positive reaction cells of luminal epithelial cells were ordered as control group, progesterone-treated group, estrogen+progesterone-treated group, and estrogen-treated group, and glandular epithelial cells were ordered as estrogen+progesterone-treated group, progesterone-treated group, control group, and estrogen-treated group. It was suggested that estrogen and progesterone did not affect on the proliferating cells of luminal epithelial cells and affection of progesterone on the development of glandular epithelial cell was larger than that of estrogen.

• 한국정밀공학회지
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• 제29권5호
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• pp.584-590
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• 2012

The structural and functional disorder of a detrusor induces a bladder hypertrophy and degenerates a bladder muscle gradually by preventing normal urination. Thus, the thickness of the bladder wall has been increased in proportion to the degree of bladder outlet obstruction. In this study, the mechanical characteristics of the detrusor is analyzed for the physical properties and the thickness changes of the bladder muscle using a mathematically analytic method. In order to obtain the mechanical property of the bladder muscle, the tensile test of porcine bladder tissue is performed because its property is similar to that of human. The result of tensile test is applied to the mathematically model as Mooney Rivlin coefficients which represent the hyperelastic material. The model of the bladder is defined as the spherical shape with the initial volume of 50ml. The principal stress and strain according to the thickness are analyzed. Also, computer simulations for three types of the material property for the model of the bladder are performed based on the fact that the stiffness of the bladder is weakened as the progress of the benign prostatic hyperplasia. As a result, the principal stress is 341kPa at the initial thickness of 2.2mm, and is 249kPa at 6.5mm. As the bladder wall thickness increases, the principal stress decreases. The principal stress and strain decrease as the stiffness of the bladder decreases under the same thinkness.

• Asian-Australasian Journal of Animal Sciences
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• 제18권7호
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• pp.1017-1021
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• 2005

Myostatin is a negative regulator of skeletal muscle growth and a loss of functional myostatin protein increases muscle hypertrophy and hyperplasia in cattle. The present study was conducted to investigate whether maternal passive immunization against myostatin would improve growth performance in chickens. A complete broiler myostatin cDNA was cloned and it was expressed into two transcripts as 1,128 bp and 985 bp by alternative splicing. A conjugated mature myostatin (350 bp) was used to induce autoimmunization and maternal passively immunized chickens was used for the experiment. It was confirmed that there was a maternal passive immunization against myostatin at zero weeks of age, but its effect was reduced by 6 weeks of age. The auto-immunized groups showed smaller body weights than those of control group during the growing period and the difference was getting bigger with time until 6 weeks of age. These results suggest that passive autoimmunization against myostatin used in this study is not potent enough to stimulate growth performance in chickens.

• Medical Lasers
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• 제10권4호
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• pp.220-228
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• 2021

Background and Objectives In designing a resistance exercise program, intensity, rest, and exercise volume are important. Many studies have been conducted to find the most suitable resistance exercise program incorporating the above, and in particular, many prior studies have been conducted on intensity. This study attempted to determine the effective volume of exercise by analyzing the number of repetitions performed at intensities of 65% one-repetition maximum (1RM) and 75% 1RM during the bench press exercise, and the electromyography (EMG) response of the agonist muscle. Materials and Methods Eight males in their 20s were selected as study subjects and they performed five sets of bench presses at two levels of intensity (65% 1RM, 75% 1RM). The following results were obtained by measuring the number of repetitions and the EMG response according to the exercise intensity and sets during the workout. Results First, the number of repetitions showed a sharp drop from the first set to the third set at 65% 1RM intensity and showed no change in the fourth and fifth sets. At 75% 1RM intensity, the intensity of hypertrophy showed a gradual decrease from the first set to the fifth set. Second, at 75% 1RM exercise intensity, the pectoralis major, anterior deltoid and triceps brachii showed high muscle activity, and the activity of the anterior deltoid continued to increase from the first set to the fourth set at 65% 1RM intensity, and from the first set to the fifth set at 75% 1RM. Conclusion It was found that during the bench press exercise, three minutes of rest at 75% 1RM intensity, five sets of five sets, one minute rest at 65% 1RM intensity, and three sets of the exercise were effective.

• Journal of Chest Surgery
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• 제31권6호
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• pp.586-590
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• 1998

배 경: 대동맥판막협착증 환자에서 판막치환후 좌심실심근비후감소의 정도는 치환된 판막의 적절성을 고려하는 중요한 인자로 생각된다. 방 법: 1990년 7월부터 1997년 7월까지 서울중앙병원 흉부외과에서는 심근비후의 감소정도를 분석하기위해 St. Jude 판막을 치환한 대동맥판막협착증 환자 36명(남녀 각각 22명과 14명, 평균나이 54세, 평균체표면적 1.61m2)에서 수술전과 수술후 조기(7.5$\pm$2.1일)와 만기(10.7$\pm$1.8개월)에 심초음파와 심전도를 시행하였다. 사용된 판막에 따라 3개의 군(19, 21 그리고 23이상)으로 나누었다. 결 과: 19 mm 판막군에서의 평균 체표면적(1.48$\pm$0.13)은 타군(1.63$\pm$0.12)에 비해 체표면적이 작았다(p<0.05). 심박출량은 모든 군에서 수술전에 비해 수술만기에 차이가 없었다. 좌심실심근량지수는 21 mm와 23mm이상 판막군에서 수술후 만기에 유의하게 감소하였으나 19 mm 판막군은 유의한 감소를 보여주지 못했다. 심전도상 Scott의 기준에 의한 전위의 크기는 모든 크기의 판막에서 술후 만기에 감소되었다. 결 론: 19 mm 판막군에서는 임상증세의 호전에도 불구하고 좌심실심근비후의 감소가 원할하지 못해 대동맥판륜이 작은 환자에서는 판륜확장술 또는 동종이식판막치환과 같은 대책들이 필요할 것으로 사료된다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2003년도 정기총회 및 학술발표회
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• pp.23-23
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• 2003

It has been suggested that the impairment of smooth muscle cell (SMC) function by alterations in the $Ca^{2+}$-activated $K^{+}$ ( $K_{Ca}$ ) channels accounts for the reduction in coronary reserve during left ventricular hypertrophy (LVH). However, this hypothesis has not been fully investigated. The main goal of this study was to assess whether the properties of $K_{Ca}$ channels in coronary SMCs were altered during LVH. New Zealand white rabbits (0.8-1.0 kg) and Sprague-Dawley rats (300-400 g) were randomly selected to receive either an injection of isoproterenol (300 $\mu\textrm{g}$/kg body weight) or an equal volume of 0.9％ saline (1 mL/kg body weight). The animals developed LVH 10 days after injection. In patch-clamp experiments, the unitary current amplitude and open probability for the $K_{Ca}$ channels were significantly reduced in LVH patches compared with control patches. The concentration-response curve of the $K_{Ca}$ channel to [C $a^{2+}$]$_{i}$ was shifted to the right. Inhibition of the $K_{Ca}$ channels with TEA was more pronounced in LVH cells than in the control cells. The whole-cell currents of $K_{Ca}$ channels were reduced during LVH. Western blot analysis indicated no differences in $K_{Ca}$ channel expression between the control and LVH coronary SM membranes. In contraction experiments, the effect of a high $K^{+}$concentration on the resting tension of the LVH coronary artery was greater than on that of the control. The effect of TEA on the resting tension of the LVH coronary artery was reduced as compared with the effect on the control. Our findings imply a novel mechanism for reduced coronary reserve during LVH.ing LVH.

• 생명과학회지
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• 제22권4호
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• pp.447-455
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• 2012

Akt는 다양한 세포에서 성장, 발달, 증식, 분화와 같은 생리적 활성에 중요한 역할을 하고 골격근 세포에서 Akt는 재생 및 비대와 위축을 조절한다고 알려져 있다. 골격근 세포의 분화에 있어서 Akt의 역할을 밝히고자 본 연구를 수행하였다. 골격근 세포를 분화 시키기 위해 고밀도 및 저농도의 serum 상태에서 배양하며, 분화된 C2C12 근아세포는 둥근 모양에서 다핵을 가진 긴 모양으로 바뀐다. 이러한 형태학적 변화는 분화 시킨 후 2일부터 일어났다. 또한, 골격근 분화 표지인자인 myogenin D와 myogenin G의 발현은 2일 후 관찰되었다. C2C12 세포주에 Akt1 또는 Akt2의 발현을 저하시키면 이와 더불어 골격근으로의 분화도 저해됨을 확인하였고, 이와는 반대로 Akt1 또는 Akt2를 과발현 시키면 골격근으로 분화가 촉진됨을 알 수 있었다. 이와 더불어 Akt의 활성은 분화유도 2일 후부터 관찰되었고 7일 이후로는 감소하였다. Kruppel-like factor 4의 발현은 6일부터 증가하는 것이 관찰이 되었다. Kruppel-like factor 4의 발현 또한 Akt1 또는 Akt2의 발현양이 감소된 C2C12 근아세포에서 줄어들어 있는 것을 확인하였다. 또한 Kruppel-like factor 4의 프로모터 부위에 대한 전사조절능력이 Akt1 또는 Akt2의 발현을 저하시켰을 때 같이 떨어짐을 확인하였다. 이러한 결과들로 보아 Akt가 골격근 분화를 조절하는데 있어 중요하며, Kruppel-like factor 4 발현이 이를 조절하는 데 있어 중요한 역할을 할 것이라 판단된다.

• 구강회복응용과학지
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• 제26권1호
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• pp.69-75
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• 2010

A형 보툴리눔 독소(botulinum toxin type A, BTX-A)는 교근 비대의 치료에 성공적으로 적용되어 왔지만 주사 부위 근육의 약화를 초래한다. 이 연구는 BTX-A를 사람 교근에 주사한 후 최대 교합력(Maximum Bite Force, MBF) 의 변화를 측정하고, 반복 주사의 효과를 평가하기 위해 시행되었다. 30명의 자원자들을 18주간 추적 관찰하고, 최대 교합력을 측정하였다. 1차 주사로부터 18주가 경과한 후 시술에 만족한 16명은 제외하고 나머지 14명에게 반복 주사를 시행하였고, 다시 18주간 측정하였다. 평균 최대 교합력은 주사 2주 후 20% 감소하였다가 4주부터 점차 회복되었으며, 12주 뒤에는 주사 이전 수준으로 회복되었다. 최대 교합력은 주사 전과 주사 2주, 4주, 8주 후에서 유의한 차이를 보였다(p<.05). 반복 주사군(n=14)의 최대 교합력은 6주에 두드러진 감소를 보였다가(p<.05) 12주간 점차 회복되었다. 실험군이 경험한 불편감의 수준은 일반적인 저작에는 거의 영향을 미치지 않았다.

• Fisheries and Aquatic Sciences
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• 제22권11호
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• pp.25.1-25.9
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• 2019

Background: Due to the continuous demand for fish coupled with decline in capture fisheries, there is the need to increase aquaculture production to meet the demand. Aquaculture is faced with high cost of feeding since fish oil and fish meal are expensive. In view of this, there are calls to explore alternatives that are cheap and reliable. Objectives: This study on Oreochromis niloticus was conducted to evaluate the effects of replacing fish oil (FO) with palm oil (PO) at 0%, 25%, 50%, 75%, and 100% on muscle fatty acid and proximate composition as well as growthrelated enzyme activities and mRNA expression. Methods: Oreochromis niloticus were fed five experimental diets (33% crude protein and 10% crude lipid) for 8 weeks. Feed had variation in fish oil and palm oil contents. After the 8 weeks feeding trial, five fish were sampled from each tank (15 from each treatment) and euthanized using an excess dose of tricaine methane sulfonate (MS-222 at 200 mg/L). Fatty acid and enzyme activities were analyzed using standard protocols. Also, RT-qPCR was used to quantify the expression levels of selected growth-related genes. Results: Fish fed 25% PO recorded the least muscle protein content and was significantly lower than the group fed 100% PO. Paired box protein 7 (Pax-7) enzyme activity was significantly higher in the group fed 50% PO compared to the groups fed 25% PO and 100% PO, while caplain-3 (Capn-3) was significantly lower in the group fed 0% PO compared to all other groups. There was a significant difference among treatments with respect to mRNA expression of Pax-7 and Capn-3. Group fed 25% PO had significantly lower mRNA expression of Pax-7, while the group fed 75% PO recorded significantly higher mRNA expression of Capn-3 compared to groups fed 0% PO, 25% PO, and 100% PO. Pearson's correlation analysis revealed that Igf-I and Igf-II mRNA expression have significant correlation with n-3 polyunsaturated fatty acids content in muscle. Conclusion: The results suggest muscle protein content could be modified if FO is replaced with PO. Also, mRNA expression of Pax-7 and Capn-3 is affected by replacing FO with PO.