• Journal of Chest Surgery
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• v.29 no.7
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• pp.780-784
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• 1996

The localized form of subaortic stenosis shows a spectrum of pathological lesions varing from dis- crete membrane to a thickened flbromuscular collar. Aortic valve is commonly involved late in the pro- cess resulting in regurgitation. Because of the likelihood o the progressive obstruction and aortic regurgitation, early elective oper- ation should be considered for the patient with subaortic stenosis. We experienced a case of localized fibromuscular subaortic stenosis associated with aortic regurgi- tation. Excision of the fibromuscular ridge and septal myectomy-myotomy relieved the subaortic seen- osis. Regurgitant aortic valve was repaired by peeling away the Hbrotic tissue on the cusps and subcommissural annuloplasty at the each commissural area. On postoperative echocardiographic examination, the systolic pressure gradient between left ventricle and aorta decreased markedly and the aortic regurgitation was not detected at all.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.182-182
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• 2006

PLLA grafted Hydroxyapatite / polylactide (g-HA/PLA) composites were prepared by three grafting methods. The modified particles (p-HA) were dispersed more uniformly in the PLLA matrix than pure n-HA. The p-HA/PLLA composites exhibited better mechanical properties and thermal stability than the n-HA/PLLA composites. The composites also demonstrated improved cell compatibility due to the good biocompatibility of the HAP nanoparticles and the more uniform distribution of the PLLA-grafted HAP nanoparticles on the film surface. All of these results indicated that the p-HAP/PLLA nano-composites might have a promising medical application in bone repair and in bone tissue-engineering.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.2
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• pp.43-54
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• 2013

In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed.

• Archives of Reconstructive Microsurgery
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• v.12 no.2
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• pp.112-118
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• 2003

Purpose : Soft tissue defect and exposed tendons and bones with concomitant infection in the foot and lower leg have to be covered with vascularized flap as the one stage treatment. Authors have performed 6 cases of pedicled dorsalis pedis island flaps under the loupes magnification and evaluated the benefits. Materials and methods : From 1994 through 2003, we have performed 6 pedicled dorsalis pedis island flaps for reconstruction of soft tissue defects in the foot and lower leg. The causes were trauma in 3 cases, skin necrosis and secondary infection after Achilles tendon repair in 2 cases and acute osteomyelitis in 1 case. Average age was 38 years and 5 cases were male and 1 female. The results of the procedure was evaluated by survival of the island flap, comfort in putting on shoes and walking, comfort in the donor site, comfort in the recipient site and range of motion of the ankle joint. Results : All pedicled dorsalis pedis island flaps survived except 1. Three cases felt discomfort in the dorsum of foot as the donor site and 1 case of the Achilles tendon ruptured and repaired showed limited dorsiflexion of ankle joint. Conclusion : Nonmicrosurgical pedicled dorsalis pedis island flaps under the loupes magnification are one of the useful treatment methods because procedure is rapid, survival is confident and overall reconstructive results are good.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.4
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• pp.275-278
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• 1998

Recently, the clinical applications of the autogenous cancellous bone from the proximal tibial metaphysis show satisfactory results in the repair of maxillofacial bony defect or deformity. The proximal tibia has the potential to yield viable cancellous bone with a minimum of morbidity. The purpose of this study was to investigate the regeneration of a full thickness proximal tibial bone defect with covering or uncovering of cortical bone. The follow-up periods were 4, 8, and 12 weeks. Bone defect of right side was uncovered and left side was covered with cortical bone. In the experimental group (uncovered cortical bone) at 12 weeks, the inside of defect was filled to normal marrow tissue. The cortical bone defect was united of inner, outer callus at 4, 8 weeks in both study group. At 12 weeks, the cortical bone defect was remodeled and invaded by osteoclast (giant cell) in experimental group. In the experimental specimen at 12 weeks, the regenerating tissue of bone defect was not differ from the control group.

• Journal of Korean Foot and Ankle Society
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• v.17 no.1
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• pp.11-16
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• 2013

Freiberg's disease is a osteochondrosis of a metatarsal head that is recognized as primarily a disorder of the second metatarsal. It is seen more often in girls. Pain and limitation of motion of the affected joint is the predominant clincal feature. The radiographic appearance demonstrates from osteosclerosis in the early stage to osteolysis with collapse in the later stage. Conservative therapy may take the form of rest, a stiff shoe, and even a cast support to decrease the stress across the joint. Surgical intervention may also be of benefit. Surgery have been attempted either to modify the diseae process or to salvage the situation once the metatarsophalangeal joint develops degenerative changes. Metatarsophalangeal joint instability is common cause of forefoot pain that can develop in association with a traumatic episode and inflamatory tissue disorders as well as neighboring toe deformities. The second ray is by far the most frequently involved. The diagnosis can be made by clinical observation and physical examination including drawer test. Many surgical procedures have beem recommended when conservative treatment has failed. Procedures described range from soft tissue releases and tendon trasfer to the direct plantar plate repair combined with a Weil osteotomy.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.1
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• pp.93-98
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• 2006

This study examined whether or not the iron that is accumulated in the recombinant microbes that produce ferritin is bioavailable to rats with iron deficiency. Rats induced with iron deficiency were treated with iron preparations of $Fe(NH_4)_2(SO_4)_2$, horse spleen ferritin, control yeast, and ferritin-producing recombinant yeast for 14 days. The bioavailability of iron was examined by measuring hemoglobin concentration, hematocrit value, and tissue iron stores. Differences between dietary groups were determined by one-way ANOVA, at the level of significance p<0.05. Based on hemoglobin concentration and hematocrit value, iron in $Fe(NH_4)_2(SO_4)_2$, horse spleen ferritin, and ferritin-producing yeast were bioavailable in rats and cured iron deficiency. The efficacy of ferritin and ferritin-producing yeast was confirmed in establishing tissue iron stores after the induction of iron deficiency. The iron sources of ferritin and the ferritin-producing yeast seemed to be as effective for the recovery from iron deficiency as the iron compounds of ferric citrate and ferrous ammonium sulfate. The results suggest that the iron stored in ferritin of the recombinant yeast is bioavailable, and that the recombinant yeast may contribute widely as a source of iron to resolve the global problem of iron deficiency.

• KSBB Journal
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• v.20 no.1 s.90
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• pp.1-11
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• 2005

Recently, there has been extremely active in the research of stem cell biology. Stem cells have excellent potential for being the ultimate source of transplantable cells for many different tissues. Researchers hope to use stem cells to repair or replace diseased or damaged organs, leading to new treatments for human disorders that are currently incurable, including diabetes, spinal cord injury and brain diseases. There are primary sources of stem cells like embryonic stem cells and adult stem cells. Stem cells from embryos were known to give rise to every type of cell. However, embryonic stem cells still have a lot of disadvantages. First, transplanted cells sometimes grow into tumors. Second, the human embryonic stem cells that are available for research would be rejected by a patient's immune system. Tissue-matched transplants could be made by either creating a bank of stem cells from more human embryos, or by cloning a patient's DNA into existing stem cells to customize them. However, this is laborious and ethically contentious. These problems could be overcome by using adult stem cells, taken from a patient, that are treated to remove problems and then put back. Nevertheless, some researchers do not convince that adult stem cells could, like embryonic ones, make every tissue type. Human stem cell research holds enormous potential for contributing to our understanding of fundamental human biology. In this review, we discuss the recent progress in stem cell research and the future therapeutic applications.

• Journal of Chest Surgery
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• v.44 no.1
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• pp.80-82
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• 2011

A 12-year-old female presented with the abnormal findings on the chest PA. The chest CT revealed a retrosternal defect of the diaphragm and a fatty opacity in the pleural cavity, resulting in a diagnosis of Morgagni hernia. It was decided to undergo a laparoscopic surgery. The retrosternal defect of the diaphragm measuring 3.5 cm in diameter was found, through which a portion of the greater omentum and the fatty tissue connected with the falciform ligament were herniated into the pleural cavity. The greater omentum was pushed back into the peritoneal cavity and the fatty tissue connected with falciform ligament was excised. The mediastinal pleura was plicated and the defect of the diaphragm was repaired primarily. Immediately after the operation, the patient developed a right pneumothorax for which a chest tube was inserted. She was discharged at the post-operative third day without any further complications.

• Biomaterials and Biomechanics in Bioengineering
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• v.4 no.1
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• pp.33-44
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• 2019

This paper presents a novel structural composition for artificial bone scaffolds with an appropriate biocompatibility and biodegradability capability. To achieve this aim, carbon nanotubes, due to their prominent mechanical properties, high biocompatibility with the body and its structural similarities with the natural bone structure are selected in component of the artificial bone structure. Also, according to the piezoelectric properties of natural bone tissue, the barium titanate, which is one of the biocompatible material with body and has piezoelectric property, is used to create self-healing ability. Furthermore, due to the fact that, most of the bone tissue is consists of hydroxyapatite, this material is also added to the artificial bone structure. Finally, polycaprolactone is used in synthetic bone composition as a proper substrate for bone growth and repair. To demonstrate, performance of the presented composition, the mechanical behaviour of the bone scaffold is simulated using ANSYS Workbench software and three dimensional finite element modelling. The obtained results are compared with mechanical behaviour of the natural bone and the previous bone scaffold compositions. The results indicated that, the modulus of elasticity, strength and toughness of the proposed composition of bone scaffold is very close to the natural bone behaviour with respect to the previous bone scaffold compositions and this composition can be employed as an appropriate replacement for bone implants.