• 대한두경부종양학회지
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• 제25권1호
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• pp.28-32
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• 2009

Background : The most frequently reported risk factors for head and neck suamous cell carcinoma are smoking and alcohol. But in a recent overview, human papilloma virus(HPV) infection was revealed the important carcinogenic factor in oropharyngeal cancer. We aimed to clarify whether HPV directly effects on the oncogenesis and biologic behavior of hean and neck squamous cell carcinoma by comparison with infection prevalence, and physical status of virus. Material and Method : We used HPV genotyping DNA chip(Biocore, Korea, Seoul) arrayed by multiple oligonucleotide probes of L1 sequence of 26 types of HPV and HPV genotypes are identified by fluorescence scanner. The copy numbers of HPV E2 and E6 open reading frames(ORF) were assessed using a TaqMan-based 5'-exonuclease quantitative real-time PCR assay. The ratio of E2 to E6 copy numbers was calculated to determine the physical status of HPV-16 viral gene. Results : We observed a significant difference in HPV prevalence between tonsillar cancer group and control group(73.1% vs. 11.6%), and most of the HPVs were type 16(87.2%) and integrated(94.1%) state. In terms of oral tongue cancer, we demonstrate that 30.5% has integrated HPV-16 in cancer tissue. But Glottic cancer only 1% is related to HPV-16 integration. Conclusion : This study revealed significant relationship of HPV prevalence with oropharyngeal and oral tongue squamous cell carcinoma. Most of HPV were 16 type and integrated or mixed, HPV-16 integration could be directly related to the carcinogenesis.

• Journal of Periodontal and Implant Science
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• 제50권2호
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• pp.106-120
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• 2020

Purpose: A new form of porous polyethylene, characterized by higher porosity and pore interconnectivity, was developed for use as a tissue-integrated implant. This study evaluated the effectiveness of porous polyethylene blocks used as an onlay bone graft in rabbit mandible in terms of tissue reaction, bone ingrowth, fibrovascularization, and graft-bone interfacial integrity. Methods: Twelve New Zealand white rabbits were randomized into 3 treatment groups according to the study period (4, 12, or 24 weeks). Cylindrical specimens measuring 5 mm in diameter and 4.5 mm in thickness were placed directly on the body of the mandible without bone bed decortication, fixed in place with a titanium screw, and covered with a collagen membrane. Histologic and histomorphometric analyses were done using hematoxylin and eosin-stained bone slices. Interfacial shear strength was tested to quantify graft-bone interfacial integrity. Results: The porous polyethylene graft was observed to integrate with the mandibular bone and exhibited tissue-bridge connections. At all postoperative time points, it was noted that the host tissues had grown deep into the pores of the porous polyethylene in the direction from the interface to the center of the graft. Both fibrovascular tissue and bone were found within the pores, but most bone ingrowth was observed at the graft-mandibular bone interface. Bone ingrowth depth and interfacial shear strength were in the range of 2.76-3.89 mm and 1.11-1.43 MPa, respectively. No significant differences among post-implantation time points were found for tissue ingrowth percentage and interfacial shear strength (P>0.05). Conclusions: Within the limits of the study, the present study revealed that the new porous polyethylene did not provoke any adverse systemic reactions. The material promoted fibrovascularization and displayed osteoconductive and osteogenic properties within and outside the contact interface. Stable interfacial integration between the graft and bone also took place.

• 한국산학기술학회논문지
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• 제21권12호
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• pp.836-844
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• 2020

현대 사회는 장기 및 인체조직기증에 대한 요구도가 높아지고 있으나, 우리나라에서 인체조직기증에 대하여 인식도와 기증률이 낮아 기증 활성화를 위한 현실적인 방안에 대한 연구가 필요할 것으로 사료된다. 본 연구는 국내외 관련 문헌고찰 및 나라별 이식 등록기구 홈페이지 자료를 참조하여, 인체조직기증과 관련한 국내 법률과 운영 제도 현황을 분석하였으며, 해외 주요 국가와 비교 고찰하였다. 본 연구를 통하여 국내 인체조직기증 활성화 방안으로 법률적 측면에서 이원화된 장기와 조직이식에 관한 법체계의 통합화, 제도 운영적 측면에서 과도한 압력이 없는 국가의 장기기증에 대한 추정적 동의 방식인 Opt-out 제도의 활성화와 사회 문화적 측면에서 대국민 홍보 활성화를 제시하였다. 그러나 추정적 동의 방식은 다양한 사회적 공론화 단계가 필요하며, 거부 의사를 위한 등록체계 운영사항에 대해 국내 실정에 맞는 이해가 있어야 할 것이다. 결론적으로 외국에 비하여 낮은 장기 및 인체조직기증을 활성화하기 위한 법적 제도 정비가 요구되며, 기증에 대한 긍정적 인식 전환, 대중 홍보 및 사후 기증자와 가족에 대한 지원 등이 필요할 것으로 사료된다.

• ALGAE
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• 제29권1호
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• pp.35-45
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• 2014

Palmaria palmata was integrated with Atlantic halibut Hippoglossus hippoglossus on a commercial farm for one year starting in November, with a temperature range of 0.4 to $19.1^{\circ}C$. The seaweed was grown in nine plastic mesh cages (each $1.25m^3$ volume) suspended in a concrete sump tank ($46m^3$) in each of three recirculating systems. Two tanks received effluent water from tanks stocked with halibut, and the third received ambient seawater serving as a control. Thalli were tumbled by continuous aeration, and held under a constant photoperiod of 16 : 8 (L : D). Palmaria stocking density was $2.95kg\;m^{-3}$ initially, increasing to $9.85kg\;m^{-3}$ after a year. Specific growth rate was highest from April to June (8.0 to $9.0^{\circ}C$), 1.1% $d^{-1}$ in the halibut effluent and 0.8% $d^{-1}$ in the control, but declined to zero or less than zero above $14^{\circ}C$. Total tissue nitrogen of Palmaria in effluent water was 4.2 to 4.4% DW from January to October, whereas tissue N in the control system declined to 3.0-3.6% DW from April to October. Tissue carbon was independent of seawater source at 39.9% DW. Estimated tank space required by Palmaria for 50% removal of the nitrogen excreted by 100 t of halibut during winter is about 29,000 to $38,000m^2$, ten times the area required for halibut culture. Fifty percent removal of carbon from the same system requires 7,200 to $9,800m^2$ cultivation area. Integration of P. palmata with Atlantic halibut is feasible below $10^{\circ}C$, but is impractical during summer months due to disintegration of thalli associated with reproductive maturation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제30권5호
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• pp.417-427
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• 2008

The aim of this study is to investigate the effect of anodizing surface to osseointegration of implant by using of resonance frequency analysis (RFA), quantitative and qualitative assessment of an anodically modified implant type with regard to osseous healing qualities. A total of 96 screw-shaped implants were prepared for this study. 72 implants were prepared by electrochemical oxidation with different ways. 24 (group 1 SP) were prepared at galvanostatic mode in 0.25M sulfuric acid and phosphoric acid. 24 (group 2GC) were prepared at galvanostatic mode in calcium glycerophosphate and calcium acetate and 24 (group 3 CMP (Calcium Metaphosphate) Coating were prepared at galvanostatic mode in 0.25M sulfuric acid and phosphoric acid followed by CMP coating. Rest of 24 (control group were as a control group of RBM surface. Bone tissue responses were evaluated by resonance frequency analysis (RFA) that were undertaken at 2, 4 and 6 weeks after implant placement in the mandible of mini-pig. Group 1 SP (anodized with sulfuric acid and phosphoric acid implants) demonstrated slightly stronger bone responses than control Group RBM. Group 2 GC (anodized surface with calcium glycerophosphate and calcium acetate implants) demonstrated no difference which were compared with control group. Group 3 GMP (anodized and CMP coated implants) demonstrated slightly stronger and faster bone responses than any other implants. But, all observation result of RF A showed no significant differences between experimental groups with various surface type. Histomorphometric evaluation demonstrated significantly higher bone-to-implant contact for group 2 GC. Significantly more bone formation was found inside threaded area for group 2 GC. It was concluded that group 2 GC (anodized surface with calcium glycerophosphate and calcium acetate implants) showed more effects on the bone tissue responses than RBM surface in initial period of implantation. In addition, CMP showed a tendency to promote bone tissue responses.

• Journal of Korean Dental Science
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• 제15권1호
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• pp.19-30
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• 2022

Purpose: The purpose of the study was to assess the validity of three-dimensional (3D) facial scan taken with facial scanner and digital photo wrapping on the cone-beam computed tomography (CBCT). Materials and Methods: Twenty-five patients had their CBCT scan, two-dimensional (2D) standardized frontal photographs and 3D facial scan obtained on the same day. The facial scans were taken with a facial scanner in an upright position. The 2D standardized frontal photographs were taken at a fixed distance from patients using a camera fixed to a cephalometric apparatus. The 2D integrated facial models were created using digital photo wrapping of frontal photographs on the corresponding CBCT images. The 3D integrated facial models were created using the integration process of 3D facial scans on the CBCT images. On the integrated facial models, sixteen soft tissue landmarks were identified, and the vertical, horizontal, oblique and angular distances between soft tissue landmarks were compared among the 2D facial models and 3D facial models, and CBCT images. Result: The results showed no significant differences of linear and angular measurements among CBCT images, 2D and 3D facial models except for Se-Sn vertical linear measurement which showed significant difference for the 3D facial models. The Bland-Altman plots showed that all measurements were within the limit of agreement. For 3D facial model, all Bland-Altman plots showed that systematic bias was less than 2.0 mm and 2.0° except for Se-Sn linear vertical measurement. For 2D facial model, the Bland-Altman plots of 6 out of 11 of the angular measurements showed systematic bias of more than 2.0°. Conclusion: The facial scan taken with facial scanner showed a clinically acceptable performance. The digital 2D photo wrapping has limitations in clinical use compared to 3D facial scans.

• 접착 및 계면
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• 제24권4호
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• pp.113-119
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• 2023

홍합의 수중 접착능력은 도파(DOPA)와 라이신(Lysine), 히스티딘(Histidine)과 같은 홍합접착단백질의 아미노산 잔기가 중요한 역할을 한다고 보고되었고, 이에 따라, 카테콜과 아민기를 동시에 갖는 접착성 카테콜아민(Catecholamine) 물질을 기반으로 다양한 의공학적 연구가 진행되고 있다. 카테콜기가 도입된 키토산은 아민이 풍부한 키토산에 카테콜기를 도입한 카테콜아민으로, 이를 이용하여 조직접착제나 창상치유제, 지혈제, 약물전달체 및 조직공학용 담체 등 다양한 의공학적 적용이 가능하다. 특히, 키토산-카테콜 물질은 지혈제로 미국 및 한국 식품의약품안전처의 승인을 받아, 연구개발에서부터 제품개발까지 이루어진 홍합 모사 물질이다. 이에 본 총설에서는 지혈제로써의 키토산-카테콜 물질에 대한 연구 동향을 살펴보고자 한다. 이를 위해, 카테콜기가 도입됨에 따라 나타나는 키토산-카테콜의 특성, 지혈 메커니즘, 다양한 제형에 대하여 다루고자 한다.

• Journal of Microbiology and Biotechnology
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• 제34권5호
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• pp.1003-1016
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• 2024

This study explores the potential of plant-based decellularization in regenerative medicine, a pivotal development in tissue engineering focusing on scaffold development, modification, and vascularization. Plant decellularization involves removing cellular components from plant structures, offering an eco-friendly and cost-effective alternative to traditional scaffold materials. The use of plant-derived polymers is critical, presenting both benefits and challenges, notably in mechanical properties. Integration of plant vascular networks represents a significant bioengineering breakthrough, aligning with natural design principles. The paper provides an in-depth analysis of development protocols, scaffold fabrication considerations, and illustrative case studies showcasing plant-based decellularization applications. This technique is transformative, offering sustainable scaffold design solutions with readily available plant materials capable of forming perfusable structures. Ongoing research aims to refine protocols, assess long-term implications, and adapt the process for clinical use, indicating a path toward widespread adoption. Plant-based decellularization holds promise for regenerative medicine, bridging biological sciences with engineering through eco-friendly approaches. Future perspectives include protocol optimization, understanding long-term impacts, clinical scalability, addressing mechanical limitations, fostering collaboration, exploring new research areas, and enhancing education. Collectively, these efforts envision a regenerative future where nature and scientific innovation converge to create sustainable solutions, offering hope for generations to come.

• Journal of Plant Biotechnology
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• 제3권3호
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• pp.123-129
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• 2001

Electroporation of microcalli and embryonic axes of a Brazilian Indica rice cultivar was performed. Some parameters influencing the recovery of transformed callus have been defined through transient npt II expression. Such parameters included the presence of light during incubation of microcalli used as target for electroporation, heat shock at 45$^{\circ}C$, macerozyme pre-digestion of target tissues and the number of pulses during electroporation. Transgenic calli were obtained from embryonic axes after electroporation with plasmid pDM302, which encodes the gene phosphinotricin acetyl transferase (bar) under the control of Act-1 promoter. Integration of the introduced gene into the genome was demonstrated by Southern blot hybridization.

• Journal of Microbiology and Biotechnology
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• 제15권4호
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• pp.838-843
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• 2005

Brain-derived neurotrophic factor (BDNF) is a small secretory protein and a member of the nerve growth factor (NGF) gene family. We cloned the flounder BDNF gene from a flounder brain cDNA library. The nucleotide sequence of the cloned gene showed an open reading frame (ORF) consisting of 810 bp, corresponding to 269 amino acid residues. The tissue distribution of flounder BDNF was determined by reverse transcription-polymerase chain reaction (RT-PCR) in brain, embryo, and muscle tissues. To express fBDNF using a eukaryotic expression system, we constructed the vector mpCTV-BDNF containing the fBDNF gene and transformed this vector into Chlorella ellipsoidea. Stable integration of introduced DNA was confirmed by PCR analysis of genomic DNA, and mRNA expression in C. ellipsoidae was confirmed by RT-PCR analysis.