• Development and Reproduction
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• v.21 no.4
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• pp.467-473
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• 2017

Ascidian embryos have become an important model for embryological studies, offering a simple example for mechanisms of cytoplasmic components segregation. It is a well-known example that the asymmetric segregation of mitochondria into muscle lineage cells occurs during ascidian embryogenesis. However, it is still unclear which signaling pathway is involved in this process. To obtain molecular markers for studying mechanisms involved in the asymmetric distribution of mitochondria, we have produced monoclonal antibodies, Mito-1, Mito-2 and Mito-3, that specifically recognize mitochondria-rich cytoplasm in cells of the ascidian Halocynthia roretzi embryos. These antibodies stained cytoplasm like reticular structure in epidermis cells, except for nuclei, at the early tailbud stage. Similar pattern was observed in vital staining of mitochondria with DiOC2, a fluorescent probe of mitochondria. Immunostaining with these antibodies showed that mitochondria are evenly distributed in the animal hemisphere blastomeres at cleavage stages, whereas not in the vegetal hemisphere blastomeres. Mitochondria were transferred to the presumptive muscle and nerve cord lineage cells of the marginal zone in the vegetal hemisphere more than to the presumptive mesenchyme, notochord and endoderm lineage of the central zone. Therefore, it is suggested that these antibodies will be useful markers for studying mechanisms involved in the polarized distribution of mitochondria during ascidian embryogenesis.

• Fashion & Textile Research Journal
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• v.25 no.2
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• pp.210-220
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• 2023

Recently, smart wearable products, including electromyography (EMG) measurement devices and clothing, have been developed to monitor users' exercise levels, muscle activation, and muscle balance more effectively during fitness activities. However, technical and socioeconomic barriers, such as flexibility and durability, still pose challenges in terms of comfort, ease of wear, and wearability of smart clothing, which includes devices and circuits. To address these issues, this study developed a wearable EMG device integrated with clothing to collect valid EMG signals from desired muscles while maintaining comfort, functionality, and ease of wear. After deriving a combined structure that could stably position the wearable device within the clothing, a prototype was manufactured and evaluated for fit, compression, comfort, and exercise comfort test by ten participants (height = 176.2 cm, weight = 76.4 kg, chest circumference = 101.2 cm). The study found that the prototype had smaller circumferences around the chest, waist, and abdomen compared to commercial products, resulting in lower ratings for wearing comfort and ease of wear. However, the prototype received high ratings for fitting, pressure, and the exercise comfort test. Valid signals were obtained when the EMG device was combined to the prototype for the rectus femoris muscle, indicating stable positioning of the device during exercise.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.1
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• pp.12-20
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• 2020

Cell adhesion plays an important role in the differentiation of the morphogenesis and the trophectoderm epithelium of the blastocyst. In the porcine embryo, CDH1 mediated adhesion initiates at compaction before blastocyst formation, regulated post-translationally via protein kinase C and other signaling molecules. Here we focus on muscle RAS oncogene homolog (M-RAS), which is the closest relative to the RAS related proteins and shares most regulatory and effector interactions. To characterize the effects of M-RAS on embryo compaction, we used gain- and loss-of-function strategies in porcine embryos, in which M-RAS gene structure and protein sequence are conserved. We showed that knockdown of M-RAS in zygotes reduced embryo development abilities and CDH1 expression. Moreover, the phosphorylation of ERK was also decreased in M-RAS KD embryos. Overexpression of M-RAS allows M-RAS KD embryos to rescue the embryo compaction and blastocyst formation. Collectively, these results highlight novel conserved and multiple effects of M-RAS during porcine embryo development.

• Development and Reproduction
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• v.6 no.2
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• pp.77-82
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• 2002

In ascidians, a primitive chordate, maternal cytoplasmic factors and inductive interactions are involved in the specification of cell fates in early embryos. The larval structure of ascidians is relatively simple, and the major mesodermal tissues of the tadpole larva are notochord, muscle, and mesenchyme. Formation of muscle cells is a cell-autonomous process, and localized maternal macho-l mRNA specify muscle fate in the posterior marginal zone of the early embryo. In contrast, inductive influence from endoderm precursors plays important roles in the specification of notochord and mesenchyme fates. FGF-Ras-MAPK signaling is involved In the induction of both tissues. The difference in responsiveness of the posterior mesenchyme and anterior notochord precursors to FGF signaling is caused by the presence or absence of intrinsic factors that inherited from the posterior-vegetal egg cytoplasm, respectively. In these inductions, directed signal polarizes the induced cells and promotes asymmetric cell divisions to produce two daughter cells with distinct fates.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.3
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• pp.231-237
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• 2014

Botulinum toxin has been used for treating chronic migraine under US Food and Drug Administration approval since 2010. However there is no definitive guideline for injection point. The aim of this study is to propose an effective and safe injection guideline by reviewing the previous studies.

• Clinics in Shoulder and Elbow
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• v.5 no.2
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• pp.73-80
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• 2002

Purpose: Weight lifting is a good training to control body weight, to correct body shape and to relieve stress. How-ever if the training is continued by inadequate training method and technique, the risks of the shoulder injuries are relatively high. Main Subject: The rotator cuff injury is the most common disorder to wright lifters and often results from the train- ing program of upright row, military press and pectoral deck. The chances of subacromial impingement in these postures are high because the shoulder rotates under the acromion at 90 abduction state. Shoulder instability in weight lifters can develop due to various causes. aepeated microtrauma and excessive abduction and external rotation may result in laxity of the anterior capsular structure, ligament and muscles. Behind the neck and bench press are high risk training postures. Other than those injuries, idiopathic osteolysis of distal clavicle, acromioclavicular separation, pectoralis major muscle rupture, and triceps muscle rupture nay develop. Conclusion: The best treatment option of the shoulder injury to weight lifters is to eliminate the possible risk elements for the weight lifters in training program and to provide proper and prompt treatment as soon as possible.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.121-128
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• 2007

If patients complain about sudden ill-fitting occlusal sensation(acute malocclusion), a dentist has to consider many possible causes about that. Acute malocclusion is characterized its sudden onset and mainly can be caused by teeth and its related structure problem. But we always keep on mind that acute malocclusion also can be caused by temporomandibular disorders In this 3 cases of acute malocclusion, evaluating by patient history, clinical and radiographic findings, we diagnosed them as 1. Lateral pterygoid muscle spasm, 2.. Retrodiscitis, 3. Osteoarthritis. Through this non-odontogenic acute malocclusion cases, we emphasize the key of diagnosis is on comprehensive and careful patient history taking and clinical examination.

• Archives of Plastic Surgery
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• v.41 no.6
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• pp.630-637
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• 2014

A long nose with a drooping tip is a major aesthetic problem. It creates a negative and aged appearance and looks worse when smiling. In order to rectify this problem, the underlying anatomical causes should be understood and corrected simultaneously to optimize surgical outcomes. The causes of a drooping tip of a long nose are generally classified into two mechanisms. Static causes usually result from malposition and incorrect innate shape of the nasal structure: the nasal septum, upper and lower lateral cartilages, and the ligaments in between. The dynamic causes result from the facial expression muscles, the depressor septi nasi muscle, and the levator labii superioris alaeque nasi muscle. The depressor septi nasi depresses the nasal tip and the levator labii superioris alaeque nasi pulls the alar base upwards. Many surgical methods have been introduced, but partial approaches to correct such deformities generally do not satisfy East Asians, making the problem more challenging to surgeons. Typically, East Asians have thick nasal tip soft tissue and skin, and a depressed columella and alar bases. The authors suggest that multifactorial approaches to static and dynamic factors along with ancillary causes should be considered for correcting the drooping tip of the long noses of East Asians.

• Korean Journal of Food Science and Technology
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• v.14 no.1
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• pp.30-35
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• 1982

Ultrastructural changes in endomysial connective tissue, sarcolemma, transverse ridges and myofibrillar structures with particular attention given to Z-discs. A and I-filaments induced by heating to $80^{\circ}C$ were observed by transmission and scanning electron microscopy. Muscle heated to $80^{\circ}C$ produced granulation of sarcolemma aid ultrastructural changes and coagulation were observed in endomysial and sarcolemmal connective tissue. The edvient changes in myofibrillar structure were an increase in coagulation compactness of the A-band portion of sarcomere and disintegration of the I-bands. Z-discs appeared to be relative resistant to heat but I-filaments were observed to be most heat labile.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.2
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• pp.114-120
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• 1994

To clarify the effect of storage temperature on the morphological and histological changes of plaice, Paralichthys olivaceus muscle at early stages after killing, the changes in breaking strength of muscle, morphological observation of myofibrils and histological observation of extracellular spaces during storage at $0^{\circ}C\;and\;10^{\circ}C$ were studied. The maximum breaking strength of samples stored at $0^{\circ}C$ was reached within 10hrs and then it dropped significantly (p<0.05) from 10hrs to 25hrs of storage. However, breaking strength was not increased in fresh muscle stored at $10^{\circ}C$ and gradually decreased after 10hrs storage. In myofibrils prepared from dorsal muscle immediately after death, A-band, I-band, H-band and Z-line in sarcomere were clearly distinguishable from each other. Due to muscle contraction, it was not easy to distinguish H-band from I-band observed in sarcomere stored at $0^{\circ}C$ after 10hrs storage. But, in the case of samples stored at $10^{\circ}C$, H-band could be observed dimly until 15hrs of storage. The changes in morphological myofibrils were closely related to increase of breaking strength. No extracellular space was observed among muscle cells immediately after killing. Stored samples at $0^{\circ}C$ showed extracellular spaces after 15hrs storage. On the other hand, samples stored at $10^{\circ}C$ didn't show any extracellular spaces until 15hrs storage and showed extracellular spaces after 24hrs storage. It was thought that the post-mortem tenderization of plaice muscle was closely related to the gradually disintegration of the extracellular matrix structure after killing.